Nanometer-sized tubes composed mainly of CARBON. Such nanotubes are used as probes for high-resolution structural and chemical imaging of biomolecules with ATOMIC FORCE MICROSCOPY.
Nanometer-sized tubes composed of various substances including carbon (CARBON NANOTUBES), boron nitride, or nickel vanadate.
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
NANOTUBES formed from cyclic peptides (PEPTIDES, CYCLIC). Alternating D and L linkages create planar rings that self assemble by stacking into nanotubes. They can form pores through CELL MEMBRANE causing damage to cells.
The development and use of techniques to study physical phenomena and construct structures in the nanoscale size range or smaller.
Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.
A collection of cloned peptides, or chemically synthesized peptides, frequently consisting of all possible combinations of amino acids making up an n-amino acid peptide.
Peptides whose amino and carboxy ends are linked together with a peptide bond forming a circular chain. Some of them are ANTI-INFECTIVE AGENTS. Some of them are biosynthesized non-ribosomally (PEPTIDE BIOSYNTHESIS, NON-RIBOSOMAL).
Small cationic peptides that are an important component, in most species, of early innate and induced defenses against invading microbes. In animals they are found on mucosal surfaces, within phagocytic granules, and on the surface of the body. They are also found in insects and plants. Among others, this group includes the DEFENSINS, protegrins, tachyplesins, and thionins. They displace DIVALENT CATIONS from phosphate groups of MEMBRANE LIPIDS leading to disruption of the membrane.
An allotropic form of carbon that is used in pencils, as a lubricant, and in matches and explosives. It is obtained by mining and its dust can cause lung irritation.
Analysis of PEPTIDES that are generated from the digestion or fragmentation of a protein or mixture of PROTEINS, by ELECTROPHORESIS; CHROMATOGRAPHY; or MASS SPECTROMETRY. The resulting peptide fingerprints are analyzed for a variety of purposes including the identification of the proteins in a sample, GENETIC POLYMORPHISMS, patterns of gene expression, and patterns diagnostic for diseases.
Materials which have structured components with at least one dimension in the range of 1 to 100 nanometers. These include NANOCOMPOSITES; NANOPARTICLES; NANOTUBES; and NANOWIRES.
A polyhedral CARBON structure composed of around 60-80 carbon atoms in pentagon and hexagon configuration. They are named after Buckminster Fuller because of structural resemblance to geodesic domes. Fullerenes can be made in high temperature such as arc discharge in an inert atmosphere.
Peptides composed of between two and twelve amino acids.
Nanometer-scale composite structures composed of organic molecules intimately incorporated with inorganic molecules. (Glossary of Biotechnology and Nanobiotechology Terms, 4th ed)
Any of a variety of procedures which use biomolecular probes to measure the presence or concentration of biological molecules, biological structures, microorganisms, etc., by translating a biochemical interaction at the probe surface into a quantifiable physical signal.
Electron microscopy in which the ELECTRONS or their reaction products that pass down through the specimen are imaged below the plane of the specimen.
A dark powdery deposit of unburned fuel residues, composed mainly of amorphous CARBON and some HYDROCARBONS, that accumulates in chimneys, automobile mufflers and other surfaces exposed to smoke. It is the product of incomplete combustion of carbon-rich organic fuels in low oxygen conditions. It is sometimes called lampblack or carbon black and is used in INK, in rubber tires, and to prepare CARBON NANOTUBES.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Analysis of the intensity of Raman scattering of monochromatic light as a function of frequency of the scattered light.
Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.
A PEPTIDE that is secreted by the BRAIN and the HEART ATRIA, stored mainly in cardiac ventricular MYOCARDIUM. It can cause NATRIURESIS; DIURESIS; VASODILATION; and inhibits secretion of RENIN and ALDOSTERONE. It improves heart function. It contains 32 AMINO ACIDS.
Technique whereby the weight of a sample can be followed over a period of time while its temperature is being changed (usually increased at a constant rate).
The adhesion of gases, liquids, or dissolved solids onto a surface. It includes adsorptive phenomena of bacteria and viruses onto surfaces as well. ABSORPTION into the substance may follow but not necessarily.
The branch of medicine concerned with the application of NANOTECHNOLOGY to the prevention and treatment of disease. It involves the monitoring, repair, construction, and control of human biological systems at the molecular level, using engineered nanodevices and NANOSTRUCTURES. (From Freitas Jr., Nanomedicine, vol 1, 1999).
Electric conductors through which electric currents enter or leave a medium, whether it be an electrolytic solution, solid, molten mass, gas, or vacuum.
Relating to the size of solids.
The testing of materials and devices, especially those used for PROSTHESES AND IMPLANTS; SUTURES; TISSUE ADHESIVES; etc., for hardness, strength, durability, safety, efficacy, and biocompatibility.
Characteristics or attributes of the outer boundaries of objects, including molecules.
Materials that have a limited and usually variable electrical conductivity. They are particularly useful for the production of solid-state electronic devices.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
Determination of the quantity of a material present in a mixture by measurement of its effect on the electrical conductivity of the mixture. (Webster, 3d ed)
The study of chemical changes resulting from electrical action and electrical activity resulting from chemical changes.
A highly basic, 28 amino acid neuropeptide released from intestinal mucosa. It has a wide range of biological actions affecting the cardiovascular, gastrointestinal, and respiratory systems and is neuroprotective. It binds special receptors (RECEPTORS, VASOACTIVE INTESTINAL PEPTIDE).
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
A nonmetallic element with atomic symbol C, atomic number 6, and atomic weight [12.0096; 12.0116]. It may occur as several different allotropes including DIAMOND; CHARCOAL; and GRAPHITE; and as SOOT from incompletely burned fuel.
Calcitonin gene-related peptide. A 37-amino acid peptide derived from the calcitonin gene. It occurs as a result of alternative processing of mRNA from the calcitonin gene. The neuropeptide is widely distributed in neural tissue of the brain, gut, perivascular nerves, and other tissue. The peptide produces multiple biological effects and has both circulatory and neurotransmitter modes of action. In particular, it is a potent endogenous vasodilator.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Peptides that have the ability to enter cells by crossing the plasma membrane directly, or through uptake by the endocytotic pathway.
Nanoparticles produced from metals whose uses include biosensors, optics, and catalysts. In biomedical applications the particles frequently involve the noble metals, especially gold and silver.
A dark-gray, metallic element of widespread distribution but occurring in small amounts; atomic number, 22; atomic weight, 47.90; symbol, Ti; specific gravity, 4.5; used for fixation of fractures. (Dorland, 28th ed)
The utilization of an electrical current to measure, analyze, or alter chemicals or chemical reactions in solution, cells, or tissues.
The production of PEPTIDES or PROTEINS by the constituents of a living organism. The biosynthesis of proteins on RIBOSOMES following an RNA template is termed translation (TRANSLATION, GENETIC). There are other, non-ribosomal peptide biosynthesis (PEPTIDE BIOSYNTHESIS, NUCLEIC ACID-INDEPENDENT) mechanisms carried out by PEPTIDE SYNTHASES and PEPTIDYLTRANSFERASES. Further modifications of peptide chains yield functional peptide and protein molecules.
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
A spectroscopic technique in which a range of wavelengths is presented simultaneously with an interferometer and the spectrum is mathematically derived from the pattern thus obtained.
Nanometer-scale wires made of materials that conduct electricity. They can be coated with molecules such as antibodies that will bind to proteins and other substances.
A 36-amino acid peptide produced by the L cells of the distal small intestine and colon. Peptide YY inhibits gastric and pancreatic secretion.
Established cell cultures that have the potential to propagate indefinitely.
The level of protein structure in which regular hydrogen-bond interactions within contiguous stretches of polypeptide chain give rise to alpha helices, beta strands (which align to form beta sheets) or other types of coils. This is the first folding level of protein conformation.
Enzymes which are immobilized on or in a variety of water-soluble or water-insoluble matrices with little or no loss of their catalytic activity. Since they can be reused continuously, immobilized enzymes have found wide application in the industrial, medical and research fields.
Specialized structures of the cell that extend the cell membrane and project out from the cell surface.
DNA analogs containing neutral amide backbone linkages composed of aminoethyl glycine units instead of the usual phosphodiester linkage of deoxyribose groups. Peptide nucleic acids have high biological stability and higher affinity for complementary DNA or RNA sequences than analogous DNA oligomers.
A PEPTIDE of 22 amino acids, derived mainly from cells of VASCULAR ENDOTHELIUM. It is also found in the BRAIN, major endocrine glands, and other tissues. It shares structural homology with ATRIAL NATRIURETIC FACTOR. It has vasorelaxant activity thus is important in the regulation of vascular tone and blood flow. Several high molecular weight forms containing the 22 amino acids have been identified.
Peptides that regulate the WATER-ELECTROLYTE BALANCE in the body, also known as natriuretic peptide hormones. Several have been sequenced (ATRIAL NATRIURETIC FACTOR; BRAIN NATRIURETIC PEPTIDE; C-TYPE NATRIURETIC PEPTIDE).
Compounds formed by the joining of smaller, usually repeating, units linked by covalent bonds. These compounds often form large macromolecules (e.g., BIOPOLYMERS; PLASTICS).
Systems for the delivery of drugs to target sites of pharmacological actions. Technologies employed include those concerning drug preparation, route of administration, site targeting, metabolism, and toxicity.
The rate dynamics in chemical or physical systems.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
That portion of the electromagnetic spectrum usually sensed as heat. Infrared wavelengths are longer than those of visible light, extending into the microwave frequencies. They are used therapeutically as heat, and also to warm food in restaurants.
The thermodynamic interaction between a substance and WATER.
Neuropeptide and gut hormone that helps regulate GASTRIC ACID secretion and motor function. Once released from nerves in the antrum of the STOMACH, the neuropeptide stimulates release of GASTRIN from the GASTRIN-SECRETING CELLS.
Synthetic or natural materials, other than DRUGS, that are used to replace or repair any body TISSUES or bodily function.
The properties and processes of materials that affect their behavior under force.
A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A family of G-protein-coupled receptors that was originally identified by its ability to bind N-formyl peptides such as N-FORMYLMETHIONINE LEUCYL-PHENYLALANINE. Since N-formyl peptides are found in MITOCHONDRIA and BACTERIA, this class of receptors is believed to play a role in mediating cellular responses to cellular damage and bacterial invasion. However, non-formylated peptide ligands have also been found for this receptor class.
A 27-amino acid peptide with histidine at the N-terminal and isoleucine amide at the C-terminal. The exact amino acid composition of the peptide is species dependent. The peptide is secreted in the intestine, but is found in the nervous system, many organs, and in the majority of peripheral tissues. It has a wide range of biological actions, affecting the cardiovascular, gastrointestinal, respiratory, and central nervous systems.
Ligases that catalyze the joining of adjacent AMINO ACIDS by the formation of carbon-nitrogen bonds between their carboxylic acid groups and amine groups.
Hydrolases that specifically cleave the peptide bonds found in PROTEINS and PEPTIDES. Examples of sub-subclasses for this group include EXOPEPTIDASES and ENDOPEPTIDASES.
Structures which are part of the CELL MEMBRANE or have cell membrane as a major part of their structure.
A yellow metallic element with the atomic symbol Au, atomic number 79, and atomic weight 197. It is used in jewelry, goldplating of other metals, as currency, and in dental restoration. Many of its clinical applications, such as ANTIRHEUMATIC AGENTS, are in the form of its salts.
Cell surface receptors that bind peptide messengers with high affinity and regulate intracellular signals which influence the behavior of cells.
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
A potent natriuretic and vasodilatory peptide or mixture of different-sized low molecular weight PEPTIDES derived from a common precursor and secreted mainly by the HEART ATRIUM. All these peptides share a sequence of about 20 AMINO ACIDS.
Histiocytic, inflammatory response to a foreign body. It consists of modified macrophages with multinucleated giant cells, in this case foreign-body giant cells (GIANT CELLS, FOREIGN-BODY), usually surrounded by lymphocytes.
Sites on an antigen that interact with specific antibodies.
Alkaloids extracted from various species of Cinchona.
Electrical devices that are composed of semiconductor material, with at least three connections to an external electronic circuit. They are used to amplify electrical signals, detect signals, or as switches.
Agents that modify interfacial tension of water; usually substances that have one lipophilic and one hydrophilic group in the molecule; includes soaps, detergents, emulsifiers, dispersing and wetting agents, and several groups of antiseptics.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Substances used in biomedicine or dentistry predominantly for their physical, as opposed to chemical, properties.
Materials fabricated by BIOMIMETICS techniques, i.e., based on natural processes found in biological systems.
An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.
The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
Protein precursors, also known as proproteins or prohormones, are inactive forms of proteins that undergo post-translational modification, such as cleavage, to produce the active functional protein or peptide hormone.
Nanometer sized fragments of semiconductor crystalline material which emit PHOTONS. The wavelength is based on the quantum confinement size of the dot. They can be embedded in MICROBEADS for high throughput ANALYTICAL CHEMISTRY TECHNIQUES.
The characteristic three-dimensional shape of a molecule.
A type of scanning probe microscopy in which a probe systematically rides across the surface of a sample being scanned in a raster pattern. The vertical position is recorded as a spring attached to the probe rises and falls in response to peaks and valleys on the surface. These deflections produce a topographic map of the sample.
The study of ENVIRONMENTAL POLLUTION and the toxic effects of ENVIRONMENTAL POLLUTANTS on the ECOSYSTEM. The term was coined by Truhaut in 1969.
A mass spectrometric technique that is used for the analysis of large biomolecules. Analyte molecules are embedded in an excess matrix of small organic molecules that show a high resonant absorption at the laser wavelength used. The matrix absorbs the laser energy, thus inducing a soft disintegration of the sample-matrix mixture into free (gas phase) matrix and analyte molecules and molecular ions. In general, only molecular ions of the analyte molecules are produced, and almost no fragmentation occurs. This makes the method well suited for molecular weight determinations and mixture analysis.
The exposure to potentially harmful chemical, physical, or biological agents by inhaling them.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
Forms to which substances are incorporated to improve the delivery and the effectiveness of drugs. Drug carriers are used in drug-delivery systems such as the controlled-release technology to prolong in vivo drug actions, decrease drug metabolism, and reduce drug toxicity. Carriers are also used in designs to increase the effectiveness of drug delivery to the target sites of pharmacological actions. Liposomes, albumin microspheres, soluble synthetic polymers, DNA complexes, protein-drug conjugates, and carrier erythrocytes among others have been employed as biodegradable drug carriers.
A serine endopeptidase that is formed from TRYPSINOGEN in the pancreas. It is converted into its active form by ENTEROPEPTIDASE in the small intestine. It catalyzes hydrolysis of the carboxyl group of either arginine or lysine. EC 3.4.21.4.
An isoform of DNA that occurs in an environment rich in SODIUM and POTASSIUM ions. It is a right-handed helix with 11 base pairs per turn, a pitch of 0.256 nm per base pair and a helical diameter of 2.3 nm.
An interdisciplinary field in materials science, ENGINEERING, and BIOLOGY, studying the use of biological principles for synthesis or fabrication of BIOMIMETIC MATERIALS.
Nanometer-sized particles that are nanoscale in three dimensions. They include nanocrystaline materials; NANOCAPSULES; METAL NANOPARTICLES; DENDRIMERS, and QUANTUM DOTS. The uses of nanoparticles include DRUG DELIVERY SYSTEMS and cancer targeting and imaging.
Submicron-sized fibers with diameters typically between 50 and 500 nanometers. The very small dimension of these fibers can generate a high surface area to volume ratio, which makes them potential candidates for various biomedical and other applications.
The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.
Fluorocarbon polymers are synthetic, high-molecular-weight compounds consisting of carbon chains with fluorine atoms replacing hydrogen atoms, known for their chemical and thermal stability, as well as their resistance to water, oil, and heat, which make them useful in various medical applications such as biocompatible coatings, drug delivery systems, and implant materials.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.
Hydrocarbons with more than one triple bond; or an oxidized form of POLYENES. They can react with SULFUR to form THIOPHENES.
Tree-like, highly branched, polymeric compounds. They grow three-dimensionally by the addition of shells of branched molecules to a central core. The overall globular shape and presence of cavities gives potential as drug carriers and CONTRAST AGENTS.
Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.
Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.
Inbred C57BL mice are a strain of laboratory mice that have been produced by many generations of brother-sister matings, resulting in a high degree of genetic uniformity and homozygosity, making them widely used for biomedical research, including studies on genetics, immunology, cancer, and neuroscience.
The endogenous peptides with opiate-like activity. The three major classes currently recognized are the ENKEPHALINS, the DYNORPHINS, and the ENDORPHINS. Each of these families derives from different precursors, proenkephalin, prodynorphin, and PRO-OPIOMELANOCORTIN, respectively. There are also at least three classes of OPIOID RECEPTORS, but the peptide families do not map to the receptors in a simple way.
Proteins and peptides that are involved in SIGNAL TRANSDUCTION within the cell. Included here are peptides and proteins that regulate the activity of TRANSCRIPTION FACTORS and cellular processes in response to signals from CELL SURFACE RECEPTORS. Intracellular signaling peptide and proteins may be part of an enzymatic signaling cascade or act through binding to and modifying the action of other signaling factors.
Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.
The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)
Hormones synthesized from amino acids. They are distinguished from INTERCELLULAR SIGNALING PEPTIDES AND PROTEINS in that their actions are systemic.
Products or parts of products used to detect, manipulate, or analyze light, such as LENSES, refractors, mirrors, filters, prisms, and OPTICAL FIBERS.
A technique of measuring the dielectric properties of materials, which vary over a range of frequencies depending on the physical properties of the material. The technique involves measuring, over a range of frequencies, ELECTRICAL IMPEDANCE and phase shift of an electric field as it passes through the material.
Hard, amorphous, brittle, inorganic, usually transparent, polymerous silicate of basic oxides, usually potassium or sodium. It is used in the form of hard sheets, vessels, tubing, fibers, ceramics, beads, etc.
Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.
The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
Organic compounds that contain silicon as an integral part of the molecule.
Proteins prepared by recombinant DNA technology.
Physical reactions involved in the formation of or changes in the structure of atoms and molecules and their interactions.
Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
Nanometer-sized, hollow, spherically-shaped objects that can be utilized to encapsulate small amounts of pharmaceuticals, enzymes, or other catalysts (Glossary of Biotechnology and Nanobiotechnology, 4th ed).
The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.
A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)
The study of the energy of electrons ejected from matter by the photoelectric effect, i.e., as a direct result of absorption of energy from electromagnetic radiation. As the energies of the electrons are characteristic of a specific element, the measurement of the energy of these electrons is a technique used to determine the chemical composition of surfaces.
The heat flow across a surface per unit area per unit time, divided by the negative of the rate of change of temperature with distance in a direction perpendicular to the surface. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
Experiments designed to determine the potential toxic effects of one-time, short-term exposure to a chemical or chemicals.

Molecular dynamics investigation of an oriented cyclic peptide nanotube in DMPC bilayers. (1/11)

Nanotubes resulting from the self-assembly of cyclic peptides formed by eight alpha-amino acids and inserted into lipid bilayers have been shown to function as synthetic, integral transmembrane channels. A nanotube consisting of eight cyclo[(L-Trp-D-Leu)(3)-L-Gln-D-Leu] subunits, organized in an antiparallel, beta-sheetlike channel embedded in a hydrated dimyristoylphosphatidylcholine bilayer was investigated in an 8-ns molecular dynamics trajectory. This large-scale statistical simulation brings to light not only the atomic-level structural features of the synthetic channel, but also its dynamical properties. Overall, the nanotube conserves its hollow tubular structure. The calculation reproduces the tilt of the channel with respect to the normal of the bilayer, in reasonable agreement with experiment. The results show a dislocation of the nanotube indicative of a possible disassembly process that may influence the channel conduction. The dynamics of the water in the hollow tubular structure has been characterized, and the conductance of the channel has been estimated. Transport properties of the peptide nanotube are discussed in comparison with other transporters.  (+info)

Injectable self-assembling peptide nanofibers create intramyocardial microenvironments for endothelial cells. (2/11)

BACKGROUND: Promoting survival of transplanted cells or endogenous precursors is an important goal. We hypothesized that a novel approach to promote vascularization would be to create injectable microenvironments within the myocardium that recruit endothelial cells and promote their survival and organization. METHODS AND RESULTS: In this study we demonstrate that self-assembling peptides can be injected and that the resulting nanofiber microenvironments are readily detectable within the myocardium. Furthermore, the self-assembling peptide nanofiber microenvironments recruit progenitor cells that express endothelial markers, as determined by staining with isolectin and for the endothelial-specific protein platelet-endothelial cell adhesion molecule-1. Vascular smooth muscle cells are recruited to the microenvironment and appear to form functional vascular structures. After the endothelial cell population, cells that express alpha-sarcomeric actin and the transcription factor Nkx2.5 infiltrate the peptide microenvironment. When exogenous donor green fluorescent protein-positive neonatal cardiomyocytes were injected with the self-assembling peptides, transplanted cardiomyocytes in the peptide microenvironment survived and also augmented endogenous cell recruitment. CONCLUSIONS: These experiments demonstrate that self-assembling peptides can create nanofiber microenvironments in the myocardium and that these microenvironments promote vascular cell recruitment. Because these peptide nanofibers may be modified in a variety of ways, this approach may enable injectable tissue regeneration strategies.  (+info)

Electron transfer in Me-blocked heterodimeric alpha,gamma-peptide nanotubular donor-acceptor hybrids. (3/11)

Bio-inspired cyclopeptidic heterodimers built on beta-sheet-like hydrogen-bonding networks and bearing photoactive and electroactive chromophores on the outer surface have been prepared. Different cross-strand pairwise relationships between the side chains of the cyclic alpha,gamma-peptides afford the heterodimers as three nonequivalent dimeric species. Steady-state and time-resolved spectroscopies clearly show an electron transfer process from pi-extended tetrathiafulvalene, covalently attached to one of the cyclopeptides, to photoexcited [60]fullerene, located on the complementary cyclopeptide. The charge-separated state was stabilized for up to 1 micros before recombining and repopulating the ground state. Our current example shows that cyclopeptidic templates can be successfully used to form light-harvesting/light-converting hybrid ensembles with a distinctive organization of donor and acceptor units able to act as efficient artificial photosystems.  (+info)

Molecular origin of the self-assembly of lanreotide into nanotubes: a mutational approach. (4/11)

Lanreotide, a synthetic, therapeutic octapeptide analog of somatostatin, self-assembles in water into perfectly hollow and monodisperse (24-nm wide) nanotubes. Lanreotide is a cyclic octapeptide that contains three aromatic residues. The molecular packing of the peptide in the walls of a nanotube has recently been characterized, indicating four hierarchical levels of organization. This is a fascinating example of spontaneous self-organization, very similar to the formation of the gas vesicle walls of Halobacterium halobium. However, this unique peptide self-assembly raises important questions about its molecular origin. We adopted a directed mutation approach to determine the molecular parameters driving the formation of such a remarkable peptide architecture. We have modified the conformation by opening the cycle and by changing the conformation of a Lys residue, and we have also mutated the aromatic side chains of the peptide. We show that three parameters are essential for the formation of lanreotide nanotubes: i), the specificity of two of the three aromatic side chains, ii), the spatial arrangement of the hydrophilic and hydrophobic residues, and iii), the aromatic side chain in the beta-turn of the molecule. When these molecular characteristics are modified, either the peptides lose their self-assembling capability or they form less-ordered architectures, such as amyloid fibers and curved lamellae. Thus we have determined key elements of the molecular origins of lanreotide nanotube formation.  (+info)

Probing peptide nanotube self-assembly at a liquid-liquid interface with coarse-grained molecular dynamics. (5/11)

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Tunnelling nanotubes: a highway for prion spreading? (6/11)

The discovery of tunnelling nanotubes (TNTs) and their proposed role in long intercellular transport of organelles, bacteria and viruses have led us to examine their potential role during prion spreading. We have recently shown that these membrane bridges can form between neuronal cells, as well as between dendritic cells and primary neurons and that both endogenous and exogenous PrP(Sc) appear to traffic through these structures between infected and non-infected cells. Furthermore, prion infection can be efficiently transmitted from infected dendritic cells to primary neurons only in co-culture conditions permissive for TNT formation. Therefore, we propose a role for TNTs during prion spreading from the periphery to the central nervous system (CNS). Here, we discuss some of the key steps where TNTs might play a role during prion neuroinvasion.  (+info)

Catalytic synthesis of amino acid and peptide derivatized gadonanotubes. (7/11)

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Fas stimulation of T lymphocytes promotes rapid intercellular exchange of death signals via membrane nanotubes. (8/11)

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Carbon nanotubes (CNTs) are defined in medical literature as hollow, cylindrical structures composed of rolled graphene sheets, with diameters typically measuring on the nanoscale (ranging from 1 to several tens of nanometers) and lengths that can reach several micrometers. They can be single-walled (SWCNTs), consisting of a single layer of graphene, or multi-walled (MWCNTs), composed of multiple concentric layers of graphene.

Carbon nanotubes have unique mechanical, electrical, and thermal properties that make them promising for various biomedical applications, such as drug delivery systems, biosensors, and tissue engineering scaffolds. However, their potential toxicity and long-term effects on human health are still under investigation, particularly concerning their ability to induce oxidative stress, inflammation, and genotoxicity in certain experimental settings.

Nanotubes, in the context of nanotechnology and materials science, refer to hollow cylindrical structures with extremely small diameters, measured in nanometers (nm). They are typically composed of carbon atoms arranged in a hexagonal lattice structure, similar to graphene. The most common types of nanotubes are single-walled nanotubes (SWNTs) and multi-walled nanotubes (MWNTs).

In the field of medicine, nanotubes have been studied for their potential applications in drug delivery, tissue engineering, and medical devices. For example, researchers have explored the use of nanotubes as drug carriers, where drugs can be loaded into the hollow interior of the tube and released in a controlled manner at the target site. Additionally, nanotubes have been used to create conductive scaffolds for tissue engineering, which may help promote nerve regeneration or muscle growth.

However, it's important to note that while nanotubes have shown promise in preclinical studies, their potential use in medical applications is still being researched and developed. There are concerns about the potential toxicity of nanotubes, as well as challenges related to their large-scale production and functionalization for specific medical applications.

Peptides are short chains of amino acid residues linked by covalent bonds, known as peptide bonds. They are formed when two or more amino acids are joined together through a condensation reaction, which results in the elimination of a water molecule and the formation of an amide bond between the carboxyl group of one amino acid and the amino group of another.

Peptides can vary in length from two to about fifty amino acids, and they are often classified based on their size. For example, dipeptides contain two amino acids, tripeptides contain three, and so on. Oligopeptides typically contain up to ten amino acids, while polypeptides can contain dozens or even hundreds of amino acids.

Peptides play many important roles in the body, including serving as hormones, neurotransmitters, enzymes, and antibiotics. They are also used in medical research and therapeutic applications, such as drug delivery and tissue engineering.

Nanotubes, peptide, refer to tiny, tube-shaped structures made up of peptides, which are short chains of amino acids, the building blocks of proteins. These nanostructures have a diameter measuring on the scale of nanometers (10^-9 meters) and can be several micrometers long.

Peptide nanotubes exhibit unique physical and chemical properties that make them valuable in various fields, including biomedicine and materials science. They can serve as potential drug delivery vehicles, biosensors, scaffolds for tissue engineering, and components of nanoelectronic devices. The self-assembly of peptides into nanotubes is driven by non-covalent interactions such as hydrogen bonding, van der Waals forces, and π-π stacking.

The structure of peptide nanotubes can vary depending on the specific amino acid sequence used to form them. Some common types include cyclic peptide nanotubes, which are formed by cyclizing the peptides before self-assembly, and dipeptide nanotubes, composed of repeating units of two different amino acids. The properties and applications of peptide nanotubes can be tailored by modifying their chemical composition, length, and diameter.

Nanotechnology is not a medical term per se, but it is a field of study with potential applications in medicine. According to the National Nanotechnology Initiative, nanotechnology is defined as "the understanding and control of matter at the nanoscale, at dimensions between approximately 1 and 100 nanometers, where unique phenomena enable novel applications."

In the context of medicine, nanotechnology has the potential to revolutionize the way we diagnose, treat, and prevent diseases. Nanomedicine involves the use of nanoscale materials, devices, or systems for medical applications. These can include drug delivery systems that target specific cells or tissues, diagnostic tools that detect biomarkers at the molecular level, and tissue engineering strategies that promote regeneration and repair.

While nanotechnology holds great promise for medicine, it is still a relatively new field with many challenges to overcome, including issues related to safety, regulation, and scalability.

A peptide fragment is a short chain of amino acids that is derived from a larger peptide or protein through various biological or chemical processes. These fragments can result from the natural breakdown of proteins in the body during regular physiological processes, such as digestion, or they can be produced experimentally in a laboratory setting for research or therapeutic purposes.

Peptide fragments are often used in research to map the structure and function of larger peptides and proteins, as well as to study their interactions with other molecules. In some cases, peptide fragments may also have biological activity of their own and can be developed into drugs or diagnostic tools. For example, certain peptide fragments derived from hormones or neurotransmitters may bind to receptors in the body and mimic or block the effects of the full-length molecule.

A peptide library is a collection of a large number of peptides, which are short chains of amino acids. Each peptide in the library is typically composed of a defined length and sequence, and may contain a variety of different amino acids. Peptide libraries can be synthesized using automated techniques and are often used in scientific research to identify potential ligands (molecules that bind to specific targets) or to study the interactions between peptides and other molecules.

In a peptide library, each peptide is usually attached to a solid support, such as a resin bead, and the entire library can be created using split-and-pool synthesis techniques. This allows for the rapid and efficient synthesis of a large number of unique peptides, which can then be screened for specific activities or properties.

Peptide libraries are used in various fields such as drug discovery, proteomics, and molecular biology to identify potential therapeutic targets, understand protein-protein interactions, and develop new diagnostic tools.

Cyclic peptides are a type of peptides in which the N-terminus and C-terminus of the peptide chain are linked to form a circular structure. This is in contrast to linear peptides, which have a straight peptide backbone with a free N-terminus and C-terminus. The cyclization of peptides can occur through various mechanisms, including the formation of an amide bond between the N-terminal amino group and the C-terminal carboxylic acid group (head-to-tail cyclization), or through the formation of a bond between side chain functional groups.

Cyclic peptides have unique structural and chemical properties that make them valuable in medical and therapeutic applications. For example, they are more resistant to degradation by enzymes compared to linear peptides, which can increase their stability and half-life in the body. Additionally, the cyclic structure allows for greater conformational rigidity, which can enhance their binding affinity and specificity to target molecules.

Cyclic peptides have been explored as potential therapeutics for a variety of diseases, including cancer, infectious diseases, and neurological disorders. They have also been used as tools in basic research to study protein-protein interactions and cell signaling pathways.

Antimicrobial cationic peptides (ACPs) are a group of small, naturally occurring peptides that possess broad-spectrum antimicrobial activity against various microorganisms, including bacteria, fungi, viruses, and parasites. They are called "cationic" because they contain positively charged amino acid residues (such as lysine and arginine), which allow them to interact with and disrupt the negatively charged membranes of microbial cells.

ACPs are produced by a wide range of organisms, including humans, animals, and plants, as part of their innate immune response to infection. They play an important role in protecting the host from invading pathogens by directly killing them or inhibiting their growth.

The antimicrobial activity of ACPs is thought to be mediated by their ability to disrupt the membranes of microbial cells, leading to leakage of cellular contents and death. Some ACPs may also have intracellular targets, such as DNA or protein synthesis, that contribute to their antimicrobial activity.

ACPs are being studied for their potential use as therapeutic agents to treat infectious diseases, particularly those caused by drug-resistant bacteria. However, their clinical application is still in the early stages of development due to concerns about their potential toxicity to host cells and the emergence of resistance mechanisms in microbial pathogens.

I'm sorry for any confusion, but "graphite" is not a medical term. It is a mineral form of carbon that is used in various applications, such as pencils, lubricants, and batteries. If you have any medical questions or terms you would like defined, I'd be happy to help!

Peptide mapping is a technique used in proteomics and analytical chemistry to analyze and identify the sequence and structure of peptides or proteins. This method involves breaking down a protein into smaller peptide fragments using enzymatic or chemical digestion, followed by separation and identification of these fragments through various analytical techniques such as liquid chromatography (LC) and mass spectrometry (MS).

The resulting peptide map serves as a "fingerprint" of the protein, providing information about its sequence, modifications, and structure. Peptide mapping can be used for a variety of applications, including protein identification, characterization of post-translational modifications, and monitoring of protein degradation or cleavage.

In summary, peptide mapping is a powerful tool in proteomics that enables the analysis and identification of proteins and their modifications at the peptide level.

Nanostructures, in the context of medical and biomedical research, refer to materials or devices with structural features that have at least one dimension ranging between 1-100 nanometers (nm). At this size scale, the properties of these structures can differ significantly from bulk materials, exhibiting unique phenomena that are often influenced by quantum effects.

Nanostructures have attracted considerable interest in biomedicine due to their potential applications in various areas such as drug delivery, diagnostics, regenerative medicine, and tissue engineering. They can be fabricated from a wide range of materials including metals, polymers, ceramics, and carbon-based materials.

Some examples of nanostructures used in biomedicine include:

1. Nanoparticles: These are tiny particles with at least one dimension in the nanoscale range. They can be made from various materials like metals, polymers, or lipids and have applications in drug delivery, imaging, and diagnostics.
2. Quantum dots: These are semiconductor nanocrystals that exhibit unique optical properties due to quantum confinement effects. They are used as fluorescent labels for bioimaging and biosensing applications.
3. Carbon nanotubes: These are hollow, cylindrical structures made of carbon atoms arranged in a hexagonal lattice. They have exceptional mechanical strength, electrical conductivity, and thermal stability, making them suitable for various biomedical applications such as drug delivery, tissue engineering, and biosensors.
4. Nanofibers: These are elongated nanostructures with high aspect ratios (length much greater than width). They can be fabricated from various materials like polymers, ceramics, or composites and have applications in tissue engineering, wound healing, and drug delivery.
5. Dendrimers: These are highly branched, nanoscale polymers with a well-defined structure and narrow size distribution. They can be used as drug carriers, gene delivery vehicles, and diagnostic agents.
6. Nanoshells: These are hollow, spherical nanoparticles consisting of a dielectric core covered by a thin metallic shell. They exhibit unique optical properties that make them suitable for applications such as photothermal therapy, biosensing, and imaging.

Fullerene is not typically considered a medical term, but it is a term used in the field of materials science and nanotechnology. Fullerene refers to a specific type of carbon molecule that forms a hollow cage-like structure. The most common fullerene is buckminsterfullerene (C60), which has a soccer ball shape with 60 carbon atoms.

While fullerene itself is not a medical term, it has been studied in various medical and biomedical research contexts due to its unique chemical and physical properties. For example, fullerenes have been explored for their potential use as drug delivery vehicles, antioxidants, and imaging agents. However, more research is needed to fully understand the potential benefits and risks of using fullerene-based materials in medical applications.

Oligopeptides are defined in medicine and biochemistry as short chains of amino acids, typically containing fewer than 20 amino acid residues. These small peptides are important components in various biological processes, such as serving as signaling molecules, enzyme inhibitors, or structural elements in some proteins. They can be found naturally in foods and may also be synthesized for use in medical research and therapeutic applications.

I'm sorry for any confusion, but "nanocomposites" is not a term that has a specific medical definition. It is a term used in materials science and engineering to refer to a type of composite material where at least one of the phases has dimensions in the nanoscale (typically less than 100 nanometers). Nanocomposites can have unique properties that make them useful for various applications, including biomedical applications such as drug delivery systems or tissue engineering scaffolds. However, the term itself is not a medical definition.

Biosensing techniques refer to the methods and technologies used to detect and measure biological molecules or processes, typically through the use of a physical device or sensor. These techniques often involve the conversion of a biological response into an electrical signal that can be measured and analyzed. Examples of biosensing techniques include electrochemical biosensors, optical biosensors, and piezoelectric biosensors.

Electrochemical biosensors measure the electrical current or potential generated by a biochemical reaction at an electrode surface. This type of biosensor typically consists of a biological recognition element, such as an enzyme or antibody, that is immobilized on the electrode surface and interacts with the target analyte to produce an electrical signal.

Optical biosensors measure changes in light intensity or wavelength that occur when a biochemical reaction takes place. This type of biosensor can be based on various optical principles, such as absorbance, fluorescence, or surface plasmon resonance (SPR).

Piezoelectric biosensors measure changes in mass or frequency that occur when a biomolecule binds to the surface of a piezoelectric crystal. This type of biosensor is based on the principle that piezoelectric materials generate an electrical charge when subjected to mechanical stress, and this charge can be used to detect changes in mass or frequency that are proportional to the amount of biomolecule bound to the surface.

Biosensing techniques have a wide range of applications in fields such as medicine, environmental monitoring, food safety, and biodefense. They can be used to detect and measure a variety of biological molecules, including proteins, nucleic acids, hormones, and small molecules, as well as to monitor biological processes such as cell growth or metabolism.

Transmission electron microscopy (TEM) is a type of microscopy in which an electron beam is transmitted through a ultra-thin specimen, interacting with it as it passes through. An image is formed from the interaction of the electrons with the specimen; the image is then magnified and visualized on a fluorescent screen or recorded on an electronic detector (or photographic film in older models).

TEM can provide high-resolution, high-magnification images that can reveal the internal structure of specimens including cells, viruses, and even molecules. It is widely used in biological and materials science research to investigate the ultrastructure of cells, tissues and materials. In medicine, TEM is used for diagnostic purposes in fields such as virology and bacteriology.

It's important to note that preparing a sample for TEM is a complex process, requiring specialized techniques to create thin (50-100 nm) specimens. These include cutting ultrathin sections of embedded samples using an ultramicrotome, staining with heavy metal salts, and positive staining or negative staining methods.

"Soot" is not typically considered a medical term, but it does have relevance to public health and medicine due to its potential health effects. Soot is a general term for the fine black or brown particles that are produced when materials burn, such as in fires, industrial processes, or vehicle emissions. It is made up of a complex mixture of substances, including carbon, metals, and other organic compounds.

Inhaling soot can lead to respiratory problems, cardiovascular issues, and cancer. This is because the tiny particles can penetrate deep into the lungs and even enter the bloodstream, causing inflammation and damage to tissues. Prolonged exposure or high concentrations of soot can have more severe health effects, particularly in vulnerable populations such as children, the elderly, and those with pre-existing medical conditions.

An amino acid sequence is the specific order of amino acids in a protein or peptide molecule, formed by the linking of the amino group (-NH2) of one amino acid to the carboxyl group (-COOH) of another amino acid through a peptide bond. The sequence is determined by the genetic code and is unique to each type of protein or peptide. It plays a crucial role in determining the three-dimensional structure and function of proteins.

Spectrum analysis in the context of Raman spectroscopy refers to the measurement and interpretation of the Raman scattering spectrum of a material or sample. Raman spectroscopy is a non-destructive analytical technique that uses the inelastic scattering of light to examine the vibrational modes of molecules.

When a monochromatic light source, typically a laser, illuminates a sample, a small fraction of the scattered light undergoes a shift in frequency due to interactions with the molecular vibrations of the sample. This shift in frequency is known as the Raman shift and is unique to each chemical bond or functional group within a molecule.

In a Raman spectrum, the intensity of the scattered light is plotted against the Raman shift, which is expressed in wavenumbers (cm-1). The resulting spectrum provides a "fingerprint" of the sample's molecular structure and composition, allowing for the identification and characterization of various chemical components within the sample.

Spectrum analysis in Raman spectroscopy can reveal valuable information about the sample's crystallinity, phase transitions, polymorphism, molecular orientation, and other properties. This technique is widely used across various fields, including materials science, chemistry, biology, pharmaceuticals, and forensics, to analyze a diverse range of samples, from simple liquids and solids to complex biological tissues and nanomaterials.

Scanning electron microscopy (SEM) is a type of electron microscopy that uses a focused beam of electrons to scan the surface of a sample and produce a high-resolution image. In SEM, a beam of electrons is scanned across the surface of a specimen, and secondary electrons are emitted from the sample due to interactions between the electrons and the atoms in the sample. These secondary electrons are then detected by a detector and used to create an image of the sample's surface topography. SEM can provide detailed images of the surface of a wide range of materials, including metals, polymers, ceramics, and biological samples. It is commonly used in materials science, biology, and electronics for the examination and analysis of surfaces at the micro- and nanoscale.

Brain Natriuretic Peptide (BNP) is a type of natriuretic peptide that is primarily produced in the heart, particularly in the ventricles. Although it was initially identified in the brain, hence its name, it is now known that the cardiac ventricles are the main source of BNP in the body.

BNP is released into the bloodstream in response to increased stretching or distension of the heart muscle cells due to conditions such as heart failure, hypertension, and myocardial infarction (heart attack). Once released, BNP binds to specific receptors in the kidneys, causing an increase in urine production and excretion of sodium, which helps reduce fluid volume and decrease the workload on the heart.

BNP also acts as a hormone that regulates various physiological functions, including blood pressure, cardiac remodeling, and inflammation. Measuring BNP levels in the blood is a useful diagnostic tool for detecting and monitoring heart failure, as higher levels of BNP are associated with more severe heart dysfunction.

Thermogravimetry (TG) is a technique used in materials science and analytical chemistry to measure the mass of a substance as a function of temperature while it is subjected to a controlled heating or cooling rate in a carefully controlled atmosphere. The sample is placed in a pan which is suspended from a balance and heated at a constant rate. As the temperature increases, various components of the sample may decompose, lose water, or evolve gases, resulting in a decrease in mass, which is recorded by the balance.

TG can be used to determine the weight loss due to decomposition, desorption, or volatilization, and to calculate the amount of various components present in a sample. It is often used in conjunction with other techniques such as differential thermal analysis (DTA) or differential scanning calorimetry (DSC) to provide additional information about the thermal behavior of materials.

In summary, thermogravimetry is a method for measuring the mass changes of a material as it is heated or cooled, which can be used to analyze its composition and thermal stability.

Adsorption is a process in which atoms, ions, or molecules from a gas, liquid, or dissolved solid accumulate on the surface of a material. This occurs because the particles in the adsorbate (the substance being adsorbed) have forces that attract them to the surface of the adsorbent (the material that the adsorbate is adhering to).

In medical terms, adsorption can refer to the use of materials with adsorptive properties to remove harmful substances from the body. For example, activated charcoal is sometimes used in the treatment of poisoning because it can adsorb a variety of toxic substances and prevent them from being absorbed into the bloodstream.

It's important to note that adsorption is different from absorption, which refers to the process by which a substance is taken up and distributed throughout a material or tissue.

Nanomedicine is a branch of medicine that utilizes nanotechnology, which deals with materials, devices, or systems at the nanometer scale (typically between 1-100 nm), to prevent and treat diseases. It involves the development of novel therapeutics, diagnostics, and medical devices that can interact with biological systems at the molecular level for improved detection, monitoring, and targeted treatment of various diseases and conditions.

Nanomedicine encompasses several areas, including:

1. Drug delivery: Nanocarriers such as liposomes, polymeric nanoparticles, dendrimers, and inorganic nanoparticles can be used to encapsulate drugs, enhancing their solubility, stability, and targeted delivery to specific cells or tissues, thereby reducing side effects.
2. Diagnostics: Nanoscale biosensors and imaging agents can provide early detection and monitoring of diseases with high sensitivity and specificity, enabling personalized medicine and improved patient outcomes.
3. Regenerative medicine: Nanomaterials can be used to create scaffolds and matrices for tissue engineering, promoting cell growth, differentiation, and vascularization in damaged or diseased tissues.
4. Gene therapy: Nanoparticles can be employed to deliver genetic material such as DNA, RNA, or gene-editing tools (e.g., CRISPR-Cas9) for the targeted correction of genetic disorders or cancer treatment.
5. Medical devices: Nanotechnology can improve the performance and functionality of medical devices by enhancing their biocompatibility, strength, and electrical conductivity, as well as incorporating sensing and drug delivery capabilities.

Overall, nanomedicine holds great promise for addressing unmet medical needs, improving diagnostic accuracy, and developing more effective therapies with reduced side effects. However, it also presents unique challenges related to safety, regulation, and scalability that must be addressed before widespread clinical adoption.

An electrode is a medical device that can conduct electrical currents and is used to transmit or receive electrical signals, often in the context of medical procedures or treatments. In a medical setting, electrodes may be used for a variety of purposes, such as:

1. Recording electrical activity in the body: Electrodes can be attached to the skin or inserted into body tissues to measure electrical signals produced by the heart, brain, muscles, or nerves. This information can be used to diagnose medical conditions, monitor the effectiveness of treatments, or guide medical procedures.
2. Stimulating nerve or muscle activity: Electrodes can be used to deliver electrical impulses to nerves or muscles, which can help to restore function or alleviate symptoms in people with certain medical conditions. For example, electrodes may be used to stimulate the nerves that control bladder function in people with spinal cord injuries, or to stimulate muscles in people with muscle weakness or paralysis.
3. Administering treatments: Electrodes can also be used to deliver therapeutic treatments, such as transcranial magnetic stimulation (TMS) for depression or deep brain stimulation (DBS) for movement disorders like Parkinson's disease. In these procedures, electrodes are implanted in specific areas of the brain and connected to a device that generates electrical impulses, which can help to regulate abnormal brain activity and improve symptoms.

Overall, electrodes play an important role in many medical procedures and treatments, allowing healthcare professionals to diagnose and treat a wide range of conditions that affect the body's electrical systems.

In the context of medical and health sciences, particle size generally refers to the diameter or dimension of particles, which can be in the form of solid particles, droplets, or aerosols. These particles may include airborne pollutants, pharmaceutical drugs, or medical devices such as nanoparticles used in drug delivery systems.

Particle size is an important factor to consider in various medical applications because it can affect the behavior and interactions of particles with biological systems. For example, smaller particle sizes can lead to greater absorption and distribution throughout the body, while larger particle sizes may be filtered out by the body's natural defense mechanisms. Therefore, understanding particle size and its implications is crucial for optimizing the safety and efficacy of medical treatments and interventions.

I'm happy to help! However, I must clarify that "materials testing" is not a medical term per se. It is a term used in various fields, including engineering and materials science, to describe the process of subjecting materials to different tests to evaluate their properties and performance under various conditions.

In the context of medical devices or implants, materials testing may refer to the evaluation of the physical and mechanical properties of materials used in their construction. These tests can include assessments of strength, durability, biocompatibility, and other factors that are critical to ensuring the safety and efficacy of medical devices.

Medical device manufacturers must comply with regulatory standards for materials testing to ensure that their products meet specific requirements for performance, safety, and quality. These standards may vary depending on the type of device, its intended use, and the country or region in which it will be marketed and sold.

Surface properties in the context of medical science refer to the characteristics and features of the outermost layer or surface of a biological material or structure, such as cells, tissues, organs, or medical devices. These properties can include physical attributes like roughness, smoothness, hydrophobicity or hydrophilicity, and electrical conductivity, as well as chemical properties like charge, reactivity, and composition.

In the field of biomaterials science, understanding surface properties is crucial for designing medical implants, devices, and drug delivery systems that can interact safely and effectively with biological tissues and fluids. Surface modifications, such as coatings or chemical treatments, can be used to alter surface properties and enhance biocompatibility, improve lubricity, reduce fouling, or promote specific cellular responses like adhesion, proliferation, or differentiation.

Similarly, in the field of cell biology, understanding surface properties is essential for studying cell-cell interactions, cell signaling, and cell behavior. Cells can sense and respond to changes in their environment, including variations in surface properties, which can influence cell shape, motility, and function. Therefore, characterizing and manipulating surface properties can provide valuable insights into the mechanisms of cellular processes and offer new strategies for developing therapies and treatments for various diseases.

I'm sorry for any confusion, but "semiconductors" is a term from the field of materials science and electronics rather than medicine. Semiconductors are materials, often silicon-based, that have properties between conductors and insulators. They are used in various electronic devices due to their unique property of controlling the flow of electrical current. If you have any medical questions, I'd be happy to help with those instead!

Molecular models are three-dimensional representations of molecular structures that are used in the field of molecular biology and chemistry to visualize and understand the spatial arrangement of atoms and bonds within a molecule. These models can be physical or computer-generated and allow researchers to study the shape, size, and behavior of molecules, which is crucial for understanding their function and interactions with other molecules.

Physical molecular models are often made up of balls (representing atoms) connected by rods or sticks (representing bonds). These models can be constructed manually using materials such as plastic or wooden balls and rods, or they can be created using 3D printing technology.

Computer-generated molecular models, on the other hand, are created using specialized software that allows researchers to visualize and manipulate molecular structures in three dimensions. These models can be used to simulate molecular interactions, predict molecular behavior, and design new drugs or chemicals with specific properties. Overall, molecular models play a critical role in advancing our understanding of molecular structures and their functions.

Conductometry is a method used to measure the electrical conductivity of a solution, which can change in the presence of certain ions or chemical reactions. In conductometry, a conductivity probe or electrode is placed in the solution and an electrical current is passed through it. The resistance of the solution is then measured and converted into a measurement of conductivity.

Conductometry is often used to monitor chemical reactions that produce or consume ions, such as acid-base titrations, oxidation-reduction reactions, and complexation reactions. By measuring changes in conductivity over time, researchers can gain insights into the rate and extent of these reactions.

In medical research, conductometry may be used to study the electrical properties of biological tissues, such as skin or blood, or to monitor chemical processes in the body, such as the metabolism of drugs or other substances. However, it is not a commonly used diagnostic tool in clinical medicine.

Electrochemistry is a branch of chemistry that deals with the interconversion of electrical energy and chemical energy. It involves the study of chemical processes that cause electrons to move, resulting in the transfer of electrical charge, and the reverse processes by which electrical energy can be used to drive chemical reactions. This field encompasses various phenomena such as the generation of electricity from chemical sources (as in batteries), the electrolysis of substances, and corrosion. Electrochemical reactions are fundamental to many technologies, including energy storage and conversion, environmental protection, and medical diagnostics.

Vasoactive Intestinal Peptide (VIP) is a 28-amino acid polypeptide hormone that has potent vasodilatory, secretory, and neurotransmitter effects. It is widely distributed throughout the body, including in the gastrointestinal tract, where it is synthesized and released by nerve cells (neurons) in the intestinal mucosa. VIP plays a crucial role in regulating various physiological functions such as intestinal secretion, motility, and blood flow. It also has immunomodulatory effects and may play a role in neuroprotection. High levels of VIP are found in the brain, where it acts as a neurotransmitter or neuromodulator and is involved in various cognitive functions such as learning, memory, and social behavior.

Protein binding, in the context of medical and biological sciences, refers to the interaction between a protein and another molecule (known as the ligand) that results in a stable complex. This process is often reversible and can be influenced by various factors such as pH, temperature, and concentration of the involved molecules.

In clinical chemistry, protein binding is particularly important when it comes to drugs, as many of them bind to proteins (especially albumin) in the bloodstream. The degree of protein binding can affect a drug's distribution, metabolism, and excretion, which in turn influence its therapeutic effectiveness and potential side effects.

Protein-bound drugs may be less available for interaction with their target tissues, as only the unbound or "free" fraction of the drug is active. Therefore, understanding protein binding can help optimize dosing regimens and minimize adverse reactions.

In the context of medical definitions, 'carbon' is not typically used as a standalone term. Carbon is an element with the symbol C and atomic number 6, which is naturally abundant in the human body and the environment. It is a crucial component of all living organisms, forming the basis of organic compounds, such as proteins, carbohydrates, lipids, and nucleic acids (DNA and RNA).

Carbon forms strong covalent bonds with various elements, allowing for the creation of complex molecules that are essential to life. In this sense, carbon is a fundamental building block of life on Earth. However, it does not have a specific medical definition as an isolated term.

Calcitonin gene-related peptide (CGRP) is a neurotransmitter and vasodilator peptide that is widely distributed in the nervous system. It is encoded by the calcitonin gene, which also encodes calcitonin and catestatin. CGRP is produced and released by sensory nerves and plays important roles in pain transmission, modulation of inflammation, and regulation of blood flow.

CGRP exists as two forms, α-CGRP and β-CGRP, which differ slightly in their amino acid sequences but have similar biological activities. α-CGRP is found primarily in the central and peripheral nervous systems, while β-CGRP is expressed mainly in the gastrointestinal tract.

CGRP exerts its effects by binding to specific G protein-coupled receptors, which are widely distributed in various tissues, including blood vessels, smooth muscles, and sensory neurons. Activation of CGRP receptors leads to increased intracellular cyclic AMP levels, activation of protein kinase A, and subsequent relaxation of vascular smooth muscle, resulting in vasodilation.

CGRP has been implicated in several clinical conditions, including migraine, cluster headache, and inflammatory pain. Inhibition of CGRP signaling has emerged as a promising therapeutic strategy for the treatment of these disorders.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

Cell-penetrating peptides (CPPs) are short, typically less than 30 amino acids long, biologically active peptides that have the ability to cross cell membranes and deliver various cargoes into cells. They were first discovered in the early 1990s and since then have gained significant attention due to their potential applications in drug delivery, gene therapy, and diagnostics.

CPPs can be classified into three categories based on their origin: (1) protein-derived CPPs, such as Tat from HIV-1 TAT protein and Penetratin from Drosophila Antennapedia protein; (2) chimeric CPPs, which are created by fusing different parts of various peptides; and (3) synthetic CPPs, which are designed and synthesized de novo.

The mechanism of cell penetration by CPPs is not fully understood but is thought to involve several processes, including endocytosis, direct translocation, and membrane disruption. The ability of CPPs to efficiently deliver various cargoes, such as proteins, nucleic acids, and small molecules, into cells has made them attractive tools for use in biomedical research and therapeutic applications. However, their potential cytotoxicity and lack of specificity remain major challenges that need to be addressed before they can be widely used in clinical settings.

Medical definitions generally refer to terms and concepts within the medical field. The term "metal nanoparticles" is more commonly used in materials science, chemistry, and physics. However, I can provide a general scientific definition that could be relevant to medical applications:

Metal nanoparticles are tiny particles with at least one dimension ranging from 1 to 100 nanometers (nm), composed of metals or metal compounds. They have unique optical, electronic, and chemical properties due to their small size and high surface-to-volume ratio, making them useful in various fields, including medical research. In medicine, metal nanoparticles can be used in drug delivery systems, diagnostics, and therapeutic applications such as photothermal therapy and radiation therapy. Examples of metals used for nanoparticle synthesis include gold, silver, and iron.

Titanium is not a medical term, but rather a chemical element (symbol Ti, atomic number 22) that is widely used in the medical field due to its unique properties. Medically, it is often referred to as a biocompatible material used in various medical applications such as:

1. Orthopedic implants: Titanium and its alloys are used for making joint replacements (hips, knees, shoulders), bone plates, screws, and rods due to their high strength-to-weight ratio, excellent corrosion resistance, and biocompatibility.
2. Dental implants: Titanium is also commonly used in dental applications like implants, crowns, and bridges because of its ability to osseointegrate, or fuse directly with bone tissue, providing a stable foundation for replacement teeth.
3. Cardiovascular devices: Titanium alloys are used in the construction of heart valves, pacemakers, and other cardiovascular implants due to their non-magnetic properties, which prevent interference with magnetic resonance imaging (MRI) scans.
4. Medical instruments: Due to its resistance to corrosion and high strength, titanium is used in the manufacturing of various medical instruments such as surgical tools, needles, and catheters.

In summary, Titanium is a chemical element with unique properties that make it an ideal material for various medical applications, including orthopedic and dental implants, cardiovascular devices, and medical instruments.

Electrochemical techniques are a group of analytical methods used in chemistry and biochemistry that involve the study of chemical processes that cause electrons to move. These techniques use an electrochemical cell, which consists of two electrodes (a working electrode and a counter electrode) immersed in an electrolyte solution. An electrical potential is applied between the electrodes, which drives redox reactions to occur at the electrode surfaces. The resulting current that flows through the cell can be measured and related to the concentration of analytes in the solution.

There are several types of electrochemical techniques, including:

1. Voltammetry: This technique measures the current that flows through the cell as a function of the applied potential. There are several types of voltammetry, including cyclic voltammetry, differential pulse voltammetry, and square wave voltammetry.
2. Amperometry: This technique measures the current that flows through the cell at a constant potential.
3. Potentiometry: This technique measures the potential difference between the working electrode and a reference electrode at zero current flow.
4. Impedance spectroscopy: This technique measures the impedance of the electrical circuit formed by the electrochemical cell as a function of frequency.

Electrochemical techniques are widely used in various fields, such as environmental monitoring, pharmaceuticals, food analysis, and biomedical research. They offer several advantages, including high sensitivity, selectivity, and simplicity, making them a powerful tool for chemical analysis.

Peptide biosynthesis is the process by which cells synthesize peptides, short chains of amino acids. This process is mediated by enzymes called peptide synthetases, which catalyze the formation of peptide bonds between individual amino acids to create a longer chain. Peptide biosynthesis typically occurs through one of two pathways: ribosomal or non-ribosomal.

Ribosomal peptide biosynthesis involves the use of the cell's translational machinery, including the ribosome and transfer RNAs (tRNAs), to synthesize peptides from a messenger RNA (mRNA) template. This process is highly regulated and typically results in the production of small, linear peptides that are further modified by enzymes to create bioactive molecules such as hormones or neurotransmitters.

Non-ribosomal peptide biosynthesis (NRPS), on the other hand, is a more complex process that involves large multifunctional enzyme complexes called non-ribosomal peptide synthetases (NRPSs). These enzymes are capable of synthesizing a wide variety of structurally diverse peptides, including cyclic and branched peptides, as well as those containing non-proteinogenic amino acids. NRPSs typically consist of multiple modules, each responsible for adding a single amino acid to the growing peptide chain. The modular nature of NRPS systems allows for great diversity in the types of peptides that can be synthesized, making them important sources of bioactive molecules with potential therapeutic applications.

Protein conformation refers to the specific three-dimensional shape that a protein molecule assumes due to the spatial arrangement of its constituent amino acid residues and their associated chemical groups. This complex structure is determined by several factors, including covalent bonds (disulfide bridges), hydrogen bonds, van der Waals forces, and ionic bonds, which help stabilize the protein's unique conformation.

Protein conformations can be broadly classified into two categories: primary, secondary, tertiary, and quaternary structures. The primary structure represents the linear sequence of amino acids in a polypeptide chain. The secondary structure arises from local interactions between adjacent amino acid residues, leading to the formation of recurring motifs such as α-helices and β-sheets. Tertiary structure refers to the overall three-dimensional folding pattern of a single polypeptide chain, while quaternary structure describes the spatial arrangement of multiple folded polypeptide chains (subunits) that interact to form a functional protein complex.

Understanding protein conformation is crucial for elucidating protein function, as the specific three-dimensional shape of a protein directly influences its ability to interact with other molecules, such as ligands, nucleic acids, or other proteins. Any alterations in protein conformation due to genetic mutations, environmental factors, or chemical modifications can lead to loss of function, misfolding, aggregation, and disease states like neurodegenerative disorders and cancer.

Fourier Transform Infrared (FTIR) spectroscopy is a type of infrared spectroscopy that uses the Fourier transform mathematical technique to convert the raw data obtained from an interferometer into a more interpretable spectrum. This technique allows for the simultaneous collection of a wide range of wavelengths, resulting in increased sensitivity and speed compared to traditional dispersive infrared spectroscopy.

FTIR spectroscopy measures the absorption or transmission of infrared radiation by a sample as a function of frequency, providing information about the vibrational modes of the molecules present in the sample. This can be used for identification and quantification of chemical compounds, analysis of molecular structure, and investigation of chemical interactions and reactions.

In summary, FTIR spectroscopy is a powerful analytical technique that uses infrared radiation to study the vibrational properties of molecules, with increased sensitivity and speed due to the use of Fourier transform mathematical techniques and an interferometer.

I'm sorry for any confusion, but "nanowires" is not a medical term. It is a term used in the field of materials science and nanotechnology. Nanowires are one-dimensional structures with a diameter of 1-100 nanometers (nm) and an aspect ratio (length/diameter) greater than 1000. They have unique electrical, mechanical, and optical properties that make them useful in various applications such as electronics, sensors, energy storage, and biomedical devices.

Peptide YY (PYY) is a small peptide hormone consisting of 36 amino acids, that is released by the L cells in the intestinal epithelium in response to feeding. It is a member of the neuropeptide Y (NPY) family and plays a crucial role in regulating appetite and energy balance.

After eating, PYY is released into the circulation and acts on specific receptors in the hypothalamus to inhibit food intake. This anorexigenic effect of PYY is mediated by its ability to decrease gastric emptying, reduce intestinal motility, and increase satiety.

PYY has also been shown to have effects on glucose homeostasis, insulin secretion, and inflammation, making it a potential therapeutic target for the treatment of obesity, diabetes, and other metabolic disorders.

A cell line is a culture of cells that are grown in a laboratory for use in research. These cells are usually taken from a single cell or group of cells, and they are able to divide and grow continuously in the lab. Cell lines can come from many different sources, including animals, plants, and humans. They are often used in scientific research to study cellular processes, disease mechanisms, and to test new drugs or treatments. Some common types of human cell lines include HeLa cells (which come from a cancer patient named Henrietta Lacks), HEK293 cells (which come from embryonic kidney cells), and HUVEC cells (which come from umbilical vein endothelial cells). It is important to note that cell lines are not the same as primary cells, which are cells that are taken directly from a living organism and have not been grown in the lab.

Secondary protein structure refers to the local spatial arrangement of amino acid chains in a protein, typically described as regular repeating patterns held together by hydrogen bonds. The two most common types of secondary structures are the alpha-helix (α-helix) and the beta-pleated sheet (β-sheet). In an α-helix, the polypeptide chain twists around itself in a helical shape, with each backbone atom forming a hydrogen bond with the fourth amino acid residue along the chain. This forms a rigid rod-like structure that is resistant to bending or twisting forces. In β-sheets, adjacent segments of the polypeptide chain run parallel or antiparallel to each other and are connected by hydrogen bonds, forming a pleated sheet-like arrangement. These secondary structures provide the foundation for the formation of tertiary and quaternary protein structures, which determine the overall three-dimensional shape and function of the protein.

Immobilized enzymes refer to enzymes that have been restricted or fixed in a specific location and are unable to move freely. This is typically achieved through physical or chemical methods that attach the enzyme to a solid support or matrix. The immobilization of enzymes can provide several advantages, including increased stability, reusability, and ease of separation from the reaction mixture.

Immobilized enzymes are widely used in various industrial applications, such as biotransformations, biosensors, and diagnostic kits. They can also be used for the production of pharmaceuticals, food additives, and other fine chemicals. The immobilization techniques include adsorption, covalent binding, entrapment, and cross-linking.

Adsorption involves physically attaching the enzyme to a solid support through weak forces such as van der Waals interactions or hydrogen bonding. Covalent binding involves forming chemical bonds between the enzyme and the support matrix. Entrapment involves encapsulating the enzyme within a porous matrix, while cross-linking involves chemically linking multiple enzyme molecules together to form a stable structure.

Overall, immobilized enzymes offer several advantages over free enzymes, including improved stability, reusability, and ease of separation from the reaction mixture, making them valuable tools in various industrial applications.

Cell surface extensions, also known as cellular processes or protrusions, are specialized structures that extend from the plasma membrane of a eukaryotic cell. These extensions include various types of projections such as cilia, flagella, and filopodia, as well as larger and more complex structures like lamellipodia and pseudopodia.

Cilia and flagella are hair-like structures that are involved in cell movement and the sensation of external stimuli. They are composed of a core of microtubules surrounded by the plasma membrane.

Filopodia are thin, finger-like protrusions that contain bundles of actin filaments and are involved in cell motility, sensing the environment, and establishing cell-cell contacts.

Lamellipodia are sheet-like extensions composed of a branched network of actin filaments and are involved in cell migration.

Pseudopodia are large, irregularly shaped protrusions that contain a mixture of actin filaments and other cytoskeletal elements, and are involved in phagocytosis and cell motility.

These cell surface extensions play important roles in various biological processes, including cell motility, sensing the environment, establishing cell-cell contacts, and the uptake of extracellular material.

Peptide Nucleic Acids (PNAs) are synthetic, artificially produced molecules that have a structure similar to both peptides (short chains of amino acids) and nucleic acids (DNA and RNA). They consist of repeating units called "monomers" made up of a pseudopeptide backbone with nucleobases attached. The backbone is composed of N-(2-aminoethyl)glycine units, which replace the sugar-phosphate backbone found in natural nucleic acids.

PNAs are known for their high binding affinity and sequence-specific recognition of DNA and RNA molecules. They can form stable complexes with complementary DNA or RNA strands through Watson-Crick base pairing, even under conditions where normal nucleic acid hybridization is poor. This property makes them valuable tools in molecular biology for various applications such as:

1. Gene regulation and silencing
2. Antisense and antigen technologies
3. Diagnostics and biosensors
4. Study of protein-DNA interactions
5. DNA repair and mutation analysis

However, it is important to note that Peptide Nucleic Acids are not naturally occurring molecules; they are entirely synthetic and must be produced in a laboratory setting.

C-type Natriuretic Peptide (CNP) is a member of the natriuretic peptide family, which are hormones that play crucial roles in cardiovascular homeostasis and renal function. The natriuretic peptides include atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and C-type natriuretic peptide (CNP).

C-type Natriuretic Peptide is primarily produced and secreted by the endothelial cells, and to a lesser extent by the central nervous system, chondrocytes, and vascular smooth muscle cells. CNP has a relatively short half-life of approximately 2 minutes due to its rapid clearance by the natriuretic peptide receptor-C (NPR-C) and neutral endopeptidase (NEP).

The primary physiological function of C-type Natriuretic Peptide is to regulate vascular tone, endothelial cell growth, differentiation, and survival. It also plays a role in bone development and maintenance by promoting chondrocyte proliferation and differentiation. In the kidney, CNP influences renal function through its effects on natriuresis (sodium excretion), diuresis (water excretion), and vasodilation of the afferent arteriole.

CNP binds to the NPR-B receptor, which is widely expressed in various tissues, including vascular endothelial cells, cardiomyocytes, osteoblasts, chondrocytes, and neurons. The activation of NPR-B leads to increased intracellular cyclic guanosine monophosphate (cGMP) levels, which in turn activates protein kinase G (PKG), resulting in vasodilation, anti-proliferative, and natriuretic effects.

Dysregulation of C-type Natriuretic Peptide has been implicated in several pathological conditions, such as cardiovascular diseases, bone disorders, and cancer. Therefore, understanding the role of CNP in these processes may provide novel therapeutic targets for treating these diseases.

Natriuretic peptides are a group of hormones that help regulate the balance of sodium and water in the body, as well as blood volume and blood pressure. They are produced by the heart and other tissues in response to stretching or distension of the cells due to increased fluid volume.

There are several types of natriuretic peptides, including:

1. Atrial natriuretic peptide (ANP): This hormone is produced by the atria of the heart in response to stretching of the atrial walls caused by increased blood volume. ANP promotes sodium and water excretion by the kidneys, which helps lower blood pressure and reduce fluid volume.
2. Brain natriuretic peptide (BNP): This hormone is produced by the ventricles of the heart in response to stretching of the ventricular walls caused by increased blood volume or pressure. BNP also promotes sodium and water excretion by the kidneys, as well as dilating blood vessels and reducing the force of heart contractions.
3. C-type natriuretic peptide (CNP): This hormone is produced by endothelial cells lining the blood vessels and has similar effects to ANP and BNP, but its main role is to regulate bone growth and development.

Natriuretic peptides have important diagnostic and therapeutic implications in various medical conditions, such as heart failure, hypertension, and kidney disease. Elevated levels of natriuretic peptides may indicate the presence of cardiac dysfunction or damage, while administering synthetic forms of these hormones has been shown to have beneficial effects on blood pressure, fluid balance, and cardiovascular function.

In the context of medical definitions, polymers are large molecules composed of repeating subunits called monomers. These long chains of monomers can have various structures and properties, depending on the type of monomer units and how they are linked together. In medicine, polymers are used in a wide range of applications, including drug delivery systems, medical devices, and tissue engineering scaffolds. Some examples of polymers used in medicine include polyethylene, polypropylene, polystyrene, polyvinyl chloride (PVC), and biodegradable polymers such as polylactic acid (PLA) and polycaprolactone (PCL).

Drug delivery systems (DDS) refer to techniques or technologies that are designed to improve the administration of a pharmaceutical compound in terms of its efficiency, safety, and efficacy. A DDS can modify the drug release profile, target the drug to specific cells or tissues, protect the drug from degradation, and reduce side effects.

The goal of a DDS is to optimize the bioavailability of a drug, which is the amount of the drug that reaches the systemic circulation and is available at the site of action. This can be achieved through various approaches, such as encapsulating the drug in a nanoparticle or attaching it to a biomolecule that targets specific cells or tissues.

Some examples of DDS include:

1. Controlled release systems: These systems are designed to release the drug at a controlled rate over an extended period, reducing the frequency of dosing and improving patient compliance.
2. Targeted delivery systems: These systems use biomolecules such as antibodies or ligands to target the drug to specific cells or tissues, increasing its efficacy and reducing side effects.
3. Nanoparticle-based delivery systems: These systems use nanoparticles made of polymers, lipids, or inorganic materials to encapsulate the drug and protect it from degradation, improve its solubility, and target it to specific cells or tissues.
4. Biodegradable implants: These are small devices that can be implanted under the skin or into body cavities to deliver drugs over an extended period. They can be made of biodegradable materials that gradually break down and release the drug.
5. Inhalation delivery systems: These systems use inhalers or nebulizers to deliver drugs directly to the lungs, bypassing the digestive system and improving bioavailability.

Overall, DDS play a critical role in modern pharmaceutical research and development, enabling the creation of new drugs with improved efficacy, safety, and patient compliance.

In the context of medicine and pharmacology, "kinetics" refers to the study of how a drug moves throughout the body, including its absorption, distribution, metabolism, and excretion (often abbreviated as ADME). This field is called "pharmacokinetics."

1. Absorption: This is the process of a drug moving from its site of administration into the bloodstream. Factors such as the route of administration (e.g., oral, intravenous, etc.), formulation, and individual physiological differences can affect absorption.

2. Distribution: Once a drug is in the bloodstream, it gets distributed throughout the body to various tissues and organs. This process is influenced by factors like blood flow, protein binding, and lipid solubility of the drug.

3. Metabolism: Drugs are often chemically modified in the body, typically in the liver, through processes known as metabolism. These changes can lead to the formation of active or inactive metabolites, which may then be further distributed, excreted, or undergo additional metabolic transformations.

4. Excretion: This is the process by which drugs and their metabolites are eliminated from the body, primarily through the kidneys (urine) and the liver (bile).

Understanding the kinetics of a drug is crucial for determining its optimal dosing regimen, potential interactions with other medications or foods, and any necessary adjustments for special populations like pediatric or geriatric patients, or those with impaired renal or hepatic function.

In the context of medical and biological sciences, a "binding site" refers to a specific location on a protein, molecule, or cell where another molecule can attach or bind. This binding interaction can lead to various functional changes in the original protein or molecule. The other molecule that binds to the binding site is often referred to as a ligand, which can be a small molecule, ion, or even another protein.

The binding between a ligand and its target binding site can be specific and selective, meaning that only certain ligands can bind to particular binding sites with high affinity. This specificity plays a crucial role in various biological processes, such as signal transduction, enzyme catalysis, or drug action.

In the case of drug development, understanding the location and properties of binding sites on target proteins is essential for designing drugs that can selectively bind to these sites and modulate protein function. This knowledge can help create more effective and safer therapeutic options for various diseases.

Infrared rays are not typically considered in the context of medical definitions. They are a type of electromagnetic radiation with longer wavelengths than those of visible light, ranging from 700 nanometers to 1 millimeter. In the field of medicine, infrared radiation is sometimes used in therapeutic settings for its heat properties, such as in infrared saunas or infrared therapy devices. However, infrared rays themselves are not a medical condition or diagnosis.

Hydrophobic interactions: These are the interactions that occur between non-polar molecules or groups of atoms in an aqueous environment, leading to their association or aggregation. The term "hydrophobic" means "water-fearing" and describes the tendency of non-polar substances to repel water. When non-polar molecules or groups are placed in water, they tend to clump together to minimize contact with the polar water molecules. These interactions are primarily driven by the entropy increase of the system as a whole, rather than energy minimization. Hydrophobic interactions play crucial roles in various biological processes, such as protein folding, membrane formation, and molecular self-assembly.

Hydrophilic interactions: These are the interactions that occur between polar molecules or groups of atoms and water molecules. The term "hydrophilic" means "water-loving" and describes the attraction of polar substances to water. When polar molecules or groups are placed in water, they can form hydrogen bonds with the surrounding water molecules, which helps solvate them. Hydrophilic interactions contribute to the stability and functionality of various biological systems, such as protein structure, ion transport across membranes, and enzyme catalysis.

Gastrin-Releasing Peptide (GRP) is defined as a 27-amino acid peptide that shares structural and functional similarities with the C-terminal part of gastrin. It is widely distributed in the central and peripheral nervous systems, where it functions as a neurotransmitter or neuromodulator. GRP plays a crucial role in various physiological processes such as regulation of gastrointestinal motility, smooth muscle relaxation, and mucous secretion. Additionally, GRP has been implicated in several pathophysiological conditions, including cancer, where it can act as a growth factor for certain types of tumors, such as small cell lung carcinoma.

Biocompatible materials are non-toxic and non-reacting substances that can be used in medical devices, tissue engineering, and drug delivery systems without causing harm or adverse reactions to living tissues or organs. These materials are designed to mimic the properties of natural tissues and are able to integrate with biological systems without being rejected by the body's immune system.

Biocompatible materials can be made from a variety of substances, including metals, ceramics, polymers, and composites. The specific properties of these materials, such as their mechanical strength, flexibility, and biodegradability, are carefully selected to meet the requirements of their intended medical application.

Examples of biocompatible materials include titanium used in dental implants and joint replacements, polyethylene used in artificial hips, and hydrogels used in contact lenses and drug delivery systems. The use of biocompatible materials has revolutionized modern medicine by enabling the development of advanced medical technologies that can improve patient outcomes and quality of life.

I'm sorry for any confusion, but "mechanical phenomena" is not a standard medical term. The term "mechanical phenomenon" is more commonly used in the fields of physics and engineering to refer to events or processes that involve physical forces and movements, such as the movement of a lever or the flow of a fluid due to pressure differences.

If you have any questions about a specific medical concept or condition, I would be happy to try to help you with that instead!

Medical definitions of water generally describe it as a colorless, odorless, tasteless liquid that is essential for all forms of life. It is a universal solvent, making it an excellent medium for transporting nutrients and waste products within the body. Water constitutes about 50-70% of an individual's body weight, depending on factors such as age, sex, and muscle mass.

In medical terms, water has several important functions in the human body:

1. Regulation of body temperature through perspiration and respiration.
2. Acting as a lubricant for joints and tissues.
3. Facilitating digestion by helping to break down food particles.
4. Transporting nutrients, oxygen, and waste products throughout the body.
5. Helping to maintain healthy skin and mucous membranes.
6. Assisting in the regulation of various bodily functions, such as blood pressure and heart rate.

Dehydration can occur when an individual does not consume enough water or loses too much fluid due to illness, exercise, or other factors. This can lead to a variety of symptoms, including dry mouth, fatigue, dizziness, and confusion. Severe dehydration can be life-threatening if left untreated.

Formyl peptide receptors (FPRs) are a type of G protein-coupled receptors that play a crucial role in the innate immune system. They are expressed on various cells including neutrophils, monocytes, and macrophages. FPRs recognize and respond to formylated peptides derived from bacteria, mitochondria, and host proteins during cell damage or stress. Activation of FPRs triggers a variety of cellular responses, such as chemotaxis, phagocytosis, and release of inflammatory mediators, which help to eliminate invading pathogens and promote tissue repair. There are three subtypes of human FPRs (FPR1, FPR2, and FPR3) that have distinct ligand specificities and functions in the immune response.

I'm sorry for the confusion, but "Peptide PHI" is not a widely recognized or established medical term. It seems that there might be some misunderstanding or miscommunication related to this term.

If you are referring to a specific type of peptide or a research study, could you please provide more context or clarify the source of the term? I would be happy to help you with accurate and reliable information once I have a better understanding of what you are asking about.

Peptide synthases are a group of enzymes that catalyze the formation of peptide bonds between specific amino acids to produce peptides or proteins. They are responsible for the biosynthesis of many natural products, including antibiotics, bacterial toxins, and immunomodulatory peptides.

Peptide synthases are large, complex enzymes that consist of multiple domains and modules, each of which is responsible for activating and condensing specific amino acids. The activation of amino acids involves the formation of an aminoacyl-adenylate intermediate, followed by transfer of the activated amino acid to a thiol group on the enzyme. The condensation of two activated amino acids results in the formation of a peptide bond and release of adenosine monophosphate (AMP) and pyrophosphate.

Peptide synthases are found in all three domains of life, but are most commonly associated with bacteria and fungi. They play important roles in the biosynthesis of many natural products that have therapeutic potential, making them targets for drug discovery and development.

Peptide hydrolases, also known as proteases or peptidases, are a group of enzymes that catalyze the hydrolysis of peptide bonds in proteins and peptides. They play a crucial role in various biological processes such as protein degradation, digestion, cell signaling, and regulation of various physiological functions. Based on their catalytic mechanism and the specificity for the peptide bond, they are classified into several types, including serine proteases, cysteine proteases, aspartic proteases, and metalloproteases. These enzymes have important clinical applications in the diagnosis and treatment of various diseases, such as cancer, viral infections, and inflammatory disorders.

A cell membrane, also known as the plasma membrane, is a thin, flexible barrier that surrounds every cell in an organism. It is composed of two layers of phospholipid molecules, which have both hydrophilic (water-attracting) and hydrophobic (water-repelling) properties. This unique structure allows the cell membrane to selectively control the movement of materials into and out of the cell.

The cell membrane is composed of several different types of molecules, including proteins, carbohydrates, and lipids. These molecules are organized into various structures that perform specific functions:

1. Phospholipid bilayer: The main component of the cell membrane is a double layer of phospholipid molecules. Each phospholipid molecule has a hydrophilic head and two hydrophobic tails. The heads face outwards, towards the watery environment inside and outside the cell, while the tails face inwards, creating a hydrophobic barrier that is difficult for most polar molecules to cross.
2. Integral proteins: These proteins are embedded within the phospholipid bilayer and can span all or part of the membrane. They play various roles, such as serving as channels or pumps for the transport of molecules across the membrane, acting as receptors for hormones and other signaling molecules, and providing structural support to the membrane.
3. Peripheral proteins: These proteins are associated with the outer or inner surface of the cell membrane but do not span its entire thickness. They can perform various functions, such as participating in cell-cell recognition, anchoring the cytoskeleton to the membrane, and acting as enzymes that catalyze chemical reactions.
4. Glycolipids: These are lipid molecules with a carbohydrate group attached to them. They are found on the outer surface of the cell membrane and play a role in cell-cell recognition and adhesion.
5. Glycoproteins: These are proteins with carbohydrate groups attached to them. Like glycolipids, they are found on the outer surface of the cell membrane and contribute to cell-cell recognition and adhesion.
6. Membrane microdomains (rafts): These are small, highly organized regions of the cell membrane that contain a high concentration of cholesterol and sphingolipids. They provide a platform for various cellular processes, such as signal transduction, membrane trafficking, and protein sorting.
7. Membrane asymmetry: The inner and outer leaflets of the cell membrane have different lipid compositions. For example, phosphatidylserine is primarily located in the inner leaflet, while sphingomyelin and glycosphingolipids are enriched in the outer leaflet. This asymmetry plays a role in various cellular processes, such as blood clotting and apoptosis (programmed cell death).

The complex structure of the cell membrane allows it to perform its many functions, including maintaining cell shape, providing a barrier between the inside and outside of the cell, regulating the movement of molecules across the membrane, and participating in various signaling pathways.

I believe there may be some confusion in your question. Gold is typically a chemical element with the symbol Au and atomic number 79. It is a dense, soft, malleable, and ductile metal. It is one of the least reactive chemical elements and is solid under standard conditions.

However, if you are referring to "Gold" in the context of medical terminology, it may refer to:

1. Gold salts: These are a group of compounds that contain gold and are used in medicine for their anti-inflammatory properties. They have been used in the treatment of rheumatoid arthritis, although they have largely been replaced by newer drugs with fewer side effects.
2. Gold implants: In some cases, a small amount of gold may be surgically implanted into the eye to treat conditions such as age-related macular degeneration or diabetic retinopathy. The gold helps to hold the retina in place and can improve vision in some patients.
3. Gold thread embedment: This is an alternative therapy used in traditional Chinese medicine, where gold threads are embedded into the skin or acupuncture points for therapeutic purposes. However, there is limited scientific evidence to support its effectiveness.

I hope this information helps! If you have any further questions, please let me know.

Peptide receptors are a type of cell surface receptor that bind to peptide hormones and neurotransmitters. These receptors play crucial roles in various physiological processes, including regulation of appetite, pain perception, immune function, and cardiovascular homeostasis. Peptide receptors belong to the G protein-coupled receptor (GPCR) superfamily or the tyrosine kinase receptor family. Upon binding of a peptide ligand, these receptors activate intracellular signaling cascades that ultimately lead to changes in cell behavior and communication with other cells.

Peptide receptors can be classified into two main categories: metabotropic and ionotropic. Metabotropic peptide receptors are GPCRs, which activate intracellular signaling pathways through coupling with heterotrimeric G proteins. These receptors typically have seven transmembrane domains and undergo conformational changes upon ligand binding, leading to the activation of downstream effectors such as adenylyl cyclase, phospholipase C, or ion channels.

Ionotropic peptide receptors are ligand-gated ion channels that directly modulate ion fluxes across the cell membrane upon ligand binding. These receptors contain four or five subunits arranged around a central pore and undergo conformational changes to allow ion flow through the channel.

Examples of peptide receptors include:

1. Opioid receptors (μ, δ, κ) - bind endogenous opioid peptides such as enkephalins, endorphins, and dynorphins to modulate pain perception and reward processing.
2. Somatostatin receptors (SSTR1-5) - bind somatostatin and cortistatin to regulate hormone secretion, cell proliferation, and angiogenesis.
3. Neuropeptide Y receptors (Y1-Y5) - bind neuropeptide Y to modulate feeding behavior, energy metabolism, and cardiovascular function.
4. Calcitonin gene-related peptide receptor (CGRP-R) - binds calcitonin gene-related peptide to mediate vasodilation and neurogenic inflammation.
5. Bradykinin B2 receptor (B2R) - binds bradykinin to induce pain, inflammation, and vasodilation.
6. Vasoactive intestinal polypeptide receptors (VPAC1, VPAC2) - bind vasoactive intestinal peptide to regulate neurotransmission, hormone secretion, and smooth muscle contraction.
7. Oxytocin receptor (OXTR) - binds oxytocin to mediate social bonding, maternal behavior, and uterine contractions during childbirth.
8. Angiotensin II type 1 receptor (AT1R) - binds angiotensin II to regulate blood pressure, fluid balance, and cell growth.

High-performance liquid chromatography (HPLC) is a type of chromatography that separates and analyzes compounds based on their interactions with a stationary phase and a mobile phase under high pressure. The mobile phase, which can be a gas or liquid, carries the sample mixture through a column containing the stationary phase.

In HPLC, the mobile phase is a liquid, and it is pumped through the column at high pressures (up to several hundred atmospheres) to achieve faster separation times and better resolution than other types of liquid chromatography. The stationary phase can be a solid or a liquid supported on a solid, and it interacts differently with each component in the sample mixture, causing them to separate as they travel through the column.

HPLC is widely used in analytical chemistry, pharmaceuticals, biotechnology, and other fields to separate, identify, and quantify compounds present in complex mixtures. It can be used to analyze a wide range of substances, including drugs, hormones, vitamins, pigments, flavors, and pollutants. HPLC is also used in the preparation of pure samples for further study or use.

Atrial natriuretic factor (ANF), also known as atrial natriuretic peptide (ANP), is a hormone that is primarily produced and secreted by the atria of the heart in response to stretching of the cardiac muscle cells due to increased blood volume. ANF plays a crucial role in regulating body fluid homeostasis, blood pressure, and cardiovascular function.

The main physiological action of ANF is to promote sodium and water excretion by the kidneys, which helps lower blood volume and reduce blood pressure. ANF also relaxes vascular smooth muscle, dilates blood vessels, and inhibits the renin-angiotensin-aldosterone system (RAAS), further contributing to its blood pressure-lowering effects.

Defects in ANF production or action have been implicated in several cardiovascular disorders, including heart failure, hypertension, and kidney disease. Therefore, ANF and its analogs are being investigated as potential therapeutic agents for the treatment of these conditions.

A granuloma is a type of organized immune response that occurs when the body encounters a foreign substance that it cannot eliminate. A "foreign-body" granuloma specifically refers to this reaction in response to an exogenous material, such as a splinter, suture, or other types of medical implants.

Foreign-body granulomas are characterized by the formation of a collection of immune cells, including macrophages and lymphocytes, which surround and attempt to isolate the foreign material. Over time, this collection of immune cells can become walled off and form a well-circumscribed mass or nodule.

Foreign-body granulomas may cause localized symptoms such as pain, swelling, or inflammation, depending on their location and size. In some cases, they may also lead to complications such as infection or tissue damage. Treatment typically involves removing the foreign body, if possible, followed by anti-inflammatory therapy to manage any residual symptoms or complications.

An epitope is a specific region on the surface of an antigen (a molecule that can trigger an immune response) that is recognized by an antibody, B-cell receptor, or T-cell receptor. It is also commonly referred to as an antigenic determinant. Epitopes are typically composed of linear amino acid sequences or conformational structures made up of discontinuous amino acids in the antigen. They play a crucial role in the immune system's ability to differentiate between self and non-self molecules, leading to the targeted destruction of foreign substances like viruses and bacteria. Understanding epitopes is essential for developing vaccines, diagnostic tests, and immunotherapies.

Cinchona alkaloids are a group of naturally occurring chemical compounds that are found in the bark of Cinchona trees, which are native to South America. These alkaloids have been used for centuries in traditional medicine to treat various ailments, most notably malaria. The main cinchona alkaloids include quinine, quinidine, cinchonine, and cinchonidine.

Quinine is the most well-known of these alkaloids and has been used for centuries as an effective antimalarial agent. It works by interfering with the reproduction of the malaria parasite in the red blood cells. Quinine is also used to treat other medical conditions, such as leg cramps and restless legs syndrome.

Quinidine is another important cinchona alkaloid that is used primarily as an antiarrhythmic agent to treat irregular heart rhythms. It works by slowing down the electrical conduction in the heart and stabilizing its rhythm.

Cinchonine and cinchonidine have more limited medical uses, mainly as bitter-tasting ingredients in tonics and other beverages. However, they also have some medicinal properties, such as being used as antimalarial agents and antiarrhythmic drugs in some countries.

It is important to note that cinchona alkaloids can have serious side effects if not used properly, so they should only be taken under the supervision of a healthcare professional.

I'm sorry for any confusion, but "Transistors, Electronic" is not a recognized medical term. Transistors are electronic components used in various devices, including medical equipment, to amplify or switch electronic signals and electrical power. They are crucial for the functioning of numerous technologies, such as computers, smartphones, and other digital devices. However, they are not typically described in the context of medical definitions. If you have any questions related to electronics or technology that you believe could be relevant to a medical context, please provide more details so I can give a more accurate response.

Surfactants, also known as surface-active agents, are amphiphilic compounds that reduce the surface tension between two liquids or between a liquid and a solid. They contain both hydrophilic (water-soluble) and hydrophobic (water-insoluble) components in their molecular structure. This unique property allows them to interact with and stabilize interfaces, making them useful in various medical and healthcare applications.

In the medical field, surfactants are commonly used in pulmonary medicine, particularly for treating respiratory distress syndrome (RDS) in premature infants. The lungs of premature infants often lack sufficient amounts of natural lung surfactant, which can lead to RDS and other complications. Exogenous surfactants, derived from animal sources or synthetically produced, are administered to replace the missing or dysfunctional lung surfactant, improving lung compliance and gas exchange.

Surfactants also have applications in topical formulations for dermatology, as they can enhance drug penetration into the skin, reduce irritation, and improve the spreadability of creams and ointments. Additionally, they are used in diagnostic imaging to enhance contrast between tissues and improve visualization during procedures such as ultrasound and X-ray examinations.

A base sequence in the context of molecular biology refers to the specific order of nucleotides in a DNA or RNA molecule. In DNA, these nucleotides are adenine (A), guanine (G), cytosine (C), and thymine (T). In RNA, uracil (U) takes the place of thymine. The base sequence contains genetic information that is transcribed into RNA and ultimately translated into proteins. It is the exact order of these bases that determines the genetic code and thus the function of the DNA or RNA molecule.

Biomedical materials are substances that are engineered or naturally occurring, which are used in medical devices, therapies, and diagnostics to improve healthcare outcomes. These materials can include metals, ceramics, polymers, composites, and biologics such as tissues and cells. They are designed to interact with biological systems for a specific purpose, such as replacing or supporting damaged tissues or organs, delivering drugs, or diagnosing diseases.

Dental materials, on the other hand, are specifically used in dental restorations, prosthetics, and orthodontic appliances. These materials can include metals, ceramics, polymers, composites, and biologics such as dentin and enamel. They are designed to restore or replace damaged teeth or oral tissues, provide structural support, prevent tooth decay, or improve aesthetics.

Both biomedical and dental materials must meet strict safety and efficacy standards to ensure they do not harm patients and achieve their intended purpose. Research and development in these fields continue to advance, leading to new materials with improved properties and functions that can benefit healthcare and oral health.

Biomimetic materials are synthetic or natural substances that mimic the chemical, physical, and biological properties of living systems or tissues. These materials are designed to interact with cells, tissues, and organs in ways that resemble the body's own structures and processes. They can be used in a variety of medical applications, including tissue engineering, drug delivery, and medical devices.

Biomimetic materials may be composed of polymers, ceramics, metals, or composites, and they can be designed to have specific properties such as mechanical strength, biocompatibility, and degradability. They may also incorporate bioactive molecules, such as growth factors or drugs, to promote healing or prevent infection.

The goal of using biomimetic materials is to create medical solutions that are more effective, safer, and more compatible with the body than traditional synthetic materials. By mimicking the body's own structures and processes, these materials can help to reduce inflammation, promote tissue regeneration, and improve overall patient outcomes.

Mass spectrometry (MS) is an analytical technique used to identify and quantify the chemical components of a mixture or compound. It works by ionizing the sample, generating charged molecules or fragments, and then measuring their mass-to-charge ratio in a vacuum. The resulting mass spectrum provides information about the molecular weight and structure of the analytes, allowing for identification and characterization.

In simpler terms, mass spectrometry is a method used to determine what chemicals are present in a sample and in what quantities, by converting the chemicals into ions, measuring their masses, and generating a spectrum that shows the relative abundances of each ion type.

A Structure-Activity Relationship (SAR) in the context of medicinal chemistry and pharmacology refers to the relationship between the chemical structure of a drug or molecule and its biological activity or effect on a target protein, cell, or organism. SAR studies aim to identify patterns and correlations between structural features of a compound and its ability to interact with a specific biological target, leading to a desired therapeutic response or undesired side effects.

By analyzing the SAR, researchers can optimize the chemical structure of lead compounds to enhance their potency, selectivity, safety, and pharmacokinetic properties, ultimately guiding the design and development of novel drugs with improved efficacy and reduced toxicity.

Protein precursors, also known as proproteins or prohormones, are inactive forms of proteins that undergo post-translational modification to become active. These modifications typically include cleavage of the precursor protein by specific enzymes, resulting in the release of the active protein. This process allows for the regulation and control of protein activity within the body. Protein precursors can be found in various biological processes, including the endocrine system where they serve as inactive hormones that can be converted into their active forms when needed.

Quantum dots are not a medical term per se, but they are often referred to in the field of medical research and technology. Quantum dots are semiconductor nanocrystals that exhibit unique optical properties, making them useful for various applications in biology and medicine. They can range in size from 1 to 10 nanometers in diameter and can be composed of materials such as cadmium selenide (CdSe), indium arsenide (InAs), or lead sulfide (PbS).

In the medical context, quantum dots have been explored for use in bioimaging, biosensing, and drug delivery. Their small size and tunable optical properties make them ideal for tracking cells, proteins, and other biological molecules in real-time with high sensitivity and specificity. Additionally, quantum dots can be functionalized with various biomolecules, such as antibodies or peptides, to target specific cell types or disease markers.

However, it is important to note that the use of quantum dots in medical applications is still largely in the research stage, and there are concerns about their potential toxicity due to the heavy metals used in their composition. Therefore, further studies are needed to evaluate their safety and efficacy before they can be widely adopted in clinical settings.

Molecular conformation, also known as spatial arrangement or configuration, refers to the specific three-dimensional shape and orientation of atoms that make up a molecule. It describes the precise manner in which bonds between atoms are arranged around a molecular framework, taking into account factors such as bond lengths, bond angles, and torsional angles.

Conformational isomers, or conformers, are different spatial arrangements of the same molecule that can interconvert without breaking chemical bonds. These isomers may have varying energies, stability, and reactivity, which can significantly impact a molecule's biological activity and function. Understanding molecular conformation is crucial in fields such as drug design, where small changes in conformation can lead to substantial differences in how a drug interacts with its target.

Atomic Force Microscopy (AFM) is a type of microscopy that allows visualization and measurement of surfaces at the atomic level. It works by using a sharp probe, called a tip, that is mounted on a flexible cantilever. The tip is brought very close to the surface of the sample and as the sample is scanned, the forces between the tip and the sample cause the cantilever to deflect. This deflection is measured and used to generate a topographic map of the surface with extremely high resolution, often on the order of fractions of a nanometer. AFM can be used to study both conductive and non-conductive samples, and can operate in various environments, including air and liquid. It has applications in fields such as materials science, biology, and chemistry.

Ecotoxicology is the study of the harmful effects of chemicals and other stressors on living organisms and ecosystems in the environment. It involves investigating how these substances move through the environment, how they affect individual organisms, and how they impact the structure and function of whole ecosystems. The ultimate goal of ecotoxicology is to provide a scientific basis for managing the risks posed by environmental pollutants and protecting both human health and the environment.

The field of ecotoxicology draws on knowledge from a variety of disciplines, including toxicology, chemistry, biology, ecology, and environmental science. Ecotoxicologists use a range of techniques to study the effects of pollutants on organisms and ecosystems, including laboratory experiments, field studies, and computer modeling.

Some of the key topics studied in ecotoxicology include:

1. The sources, transport, and fate of environmental pollutants
2. The toxicity of chemicals to individual organisms, including their acute and chronic effects
3. The impacts of pollutants on populations, communities, and ecosystems
4. The development and validation of ecotoxicological tests and methods
5. The risk assessment and management of environmental pollutants

Overall, the field of ecotoxicology is critical for understanding and addressing the complex challenges posed by environmental pollution and protecting the health of both humans and the environment.

Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry (MALDI-MS) is a type of mass spectrometry that is used to analyze large biomolecules such as proteins and peptides. In this technique, the sample is mixed with a matrix compound, which absorbs laser energy and helps to vaporize and ionize the analyte molecules.

The matrix-analyte mixture is then placed on a target plate and hit with a laser beam, causing the matrix and analyte molecules to desorb from the plate and become ionized. The ions are then accelerated through an electric field and into a mass analyzer, which separates them based on their mass-to-charge ratio.

The separated ions are then detected and recorded as a mass spectrum, which can be used to identify and quantify the analyte molecules present in the sample. MALDI-MS is particularly useful for the analysis of complex biological samples, such as tissue extracts or biological fluids, because it allows for the detection and identification of individual components within those mixtures.

Inhalation exposure is a term used in occupational and environmental health to describe the situation where an individual breathes in substances present in the air, which could be gases, vapors, fumes, mist, or particulate matter. These substances can originate from various sources, such as industrial processes, chemical reactions, or natural phenomena.

The extent of inhalation exposure is determined by several factors, including:

1. Concentration of the substance in the air
2. Duration of exposure
3. Frequency of exposure
4. The individual's breathing rate
5. The efficiency of the individual's respiratory protection, if any

Inhalation exposure can lead to adverse health effects, depending on the toxicity and concentration of the inhaled substances. Short-term or acute health effects may include irritation of the eyes, nose, throat, or lungs, while long-term or chronic exposure can result in more severe health issues, such as respiratory diseases, neurological disorders, or cancer.

It is essential to monitor and control inhalation exposures in occupational settings to protect workers' health and ensure compliance with regulatory standards. Various methods are employed for exposure assessment, including personal air sampling, area monitoring, and biological monitoring. Based on the results of these assessments, appropriate control measures can be implemented to reduce or eliminate the risks associated with inhalation exposure.

"Cells, cultured" is a medical term that refers to cells that have been removed from an organism and grown in controlled laboratory conditions outside of the body. This process is called cell culture and it allows scientists to study cells in a more controlled and accessible environment than they would have inside the body. Cultured cells can be derived from a variety of sources, including tissues, organs, or fluids from humans, animals, or cell lines that have been previously established in the laboratory.

Cell culture involves several steps, including isolation of the cells from the tissue, purification and characterization of the cells, and maintenance of the cells in appropriate growth conditions. The cells are typically grown in specialized media that contain nutrients, growth factors, and other components necessary for their survival and proliferation. Cultured cells can be used for a variety of purposes, including basic research, drug development and testing, and production of biological products such as vaccines and gene therapies.

It is important to note that cultured cells may behave differently than they do in the body, and results obtained from cell culture studies may not always translate directly to human physiology or disease. Therefore, it is essential to validate findings from cell culture experiments using additional models and ultimately in clinical trials involving human subjects.

A drug carrier, also known as a drug delivery system or vector, is a vehicle that transports a pharmaceutical compound to a specific site in the body. The main purpose of using drug carriers is to improve the efficacy and safety of drugs by enhancing their solubility, stability, bioavailability, and targeted delivery, while minimizing unwanted side effects.

Drug carriers can be made up of various materials, including natural or synthetic polymers, lipids, inorganic nanoparticles, or even cells and viruses. They can encapsulate, adsorb, or conjugate drugs through different mechanisms, such as physical entrapment, electrostatic interaction, or covalent bonding.

Some common types of drug carriers include:

1. Liposomes: spherical vesicles composed of one or more lipid bilayers that can encapsulate hydrophilic and hydrophobic drugs.
2. Polymeric nanoparticles: tiny particles made of biodegradable polymers that can protect drugs from degradation and enhance their accumulation in target tissues.
3. Dendrimers: highly branched macromolecules with a well-defined structure and size that can carry multiple drug molecules and facilitate their release.
4. Micelles: self-assembled structures formed by amphiphilic block copolymers that can solubilize hydrophobic drugs in water.
5. Inorganic nanoparticles: such as gold, silver, or iron oxide nanoparticles, that can be functionalized with drugs and targeting ligands for diagnostic and therapeutic applications.
6. Cell-based carriers: living cells, such as red blood cells, stem cells, or immune cells, that can be loaded with drugs and used to deliver them to specific sites in the body.
7. Viral vectors: modified viruses that can infect cells and introduce genetic material encoding therapeutic proteins or RNA interference molecules.

The choice of drug carrier depends on various factors, such as the physicochemical properties of the drug, the route of administration, the target site, and the desired pharmacokinetics and biodistribution. Therefore, selecting an appropriate drug carrier is crucial for achieving optimal therapeutic outcomes and minimizing side effects.

Trypsin is a proteolytic enzyme, specifically a serine protease, that is secreted by the pancreas as an inactive precursor, trypsinogen. Trypsinogen is converted into its active form, trypsin, in the small intestine by enterokinase, which is produced by the intestinal mucosa.

Trypsin plays a crucial role in digestion by cleaving proteins into smaller peptides at specific arginine and lysine residues. This enzyme helps to break down dietary proteins into amino acids, allowing for their absorption and utilization by the body. Additionally, trypsin can activate other zymogenic pancreatic enzymes, such as chymotrypsinogen and procarboxypeptidases, thereby contributing to overall protein digestion.

A-form DNA is a less common but stable form of the double-helix structure of DNA (deoxyribonucleic acid), first identified in 1968. In the A-form, the sugar-phosphate backbone of the DNA helix is twisted more tightly and has a wider helical diameter compared to the more common B-form DNA. The base pairs in A-form DNA are also stacked closer together, which allows for better hydrogen bonding between the bases. This form is typically found in dehydrated or under-hydrated environments, such as crystalline states and dry films. It's important to note that the biological relevance of A-form DNA is not well understood, but it may play a role in certain cellular processes like transcription and replication.

Biomimetics, also known as biomimicry, is the process of mimicking or taking inspiration from nature and biological systems to design materials, structures, or processes that solve human problems. It involves studying the models, systems, and elements of nature and then applying the knowledge gained to create new technologies and solutions.

In a medical context, biomimetics can be used to develop new therapies, medical devices, and diagnostic tools. For example, researchers might look to the structure of a spider's web to design a better surgical mesh or take inspiration from the way a gecko sticks to surfaces to create a new type of adhesive bandage.

Biomimetics is an interdisciplinary field that draws on knowledge from biology, chemistry, physics, engineering, and materials science. It has the potential to lead to innovative solutions in healthcare, sustainability, energy, transportation, and other areas.

Nanoparticles are defined in the field of medicine as tiny particles that have at least one dimension between 1 to 100 nanometers (nm). They are increasingly being used in various medical applications such as drug delivery, diagnostics, and therapeutics. Due to their small size, nanoparticles can penetrate cells, tissues, and organs more efficiently than larger particles, making them ideal for targeted drug delivery and imaging.

Nanoparticles can be made from a variety of materials including metals, polymers, lipids, and dendrimers. The physical and chemical properties of nanoparticles, such as size, shape, charge, and surface chemistry, can greatly affect their behavior in biological systems and their potential medical applications.

It is important to note that the use of nanoparticles in medicine is still a relatively new field, and there are ongoing studies to better understand their safety and efficacy.

Nanofibers are defined in the medical field as fibrous structures with extremely small diameters, typically measuring between 100 nanometers to 1 micrometer. They can be made from various materials such as polymers, ceramics, or composites and have a high surface area-to-volume ratio, which makes them useful in a variety of biomedical applications. These include tissue engineering, drug delivery, wound healing, and filtration. Nanofibers can be produced using different techniques such as electrospinning, self-assembly, and phase separation.

Molecular structure, in the context of biochemistry and molecular biology, refers to the arrangement and organization of atoms and chemical bonds within a molecule. It describes the three-dimensional layout of the constituent elements, including their spatial relationships, bond lengths, and angles. Understanding molecular structure is crucial for elucidating the functions and reactivities of biological macromolecules such as proteins, nucleic acids, lipids, and carbohydrates. Various experimental techniques, like X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and cryo-electron microscopy (cryo-EM), are employed to determine molecular structures at atomic resolution, providing valuable insights into their biological roles and potential therapeutic targets.

Fluorocarbon polymers are a type of synthetic polymeric material that contain carbon-fluorine bonds. These materials are known for their chemical inertness, high stability, and resistance to heat, chemicals, and water. They are often used in various medical applications such as in the coating of medical devices, implants, and drug delivery systems due to their biocompatibility and non-reactive properties.

Fluorocarbon polymers can be classified into two main categories: perfluoropolymers and fluoropolymers. Perfluoropolymers contain only carbon and fluorine atoms, while fluoropolymers contain other elements such as hydrogen, oxygen, or nitrogen in addition to carbon and fluorine.

Examples of fluorocarbon polymers used in medical applications include polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), and ethylene tetrafluoroethylene (ETFE). These materials have a wide range of properties that make them useful in various medical applications, such as low coefficient of friction, high electrical resistance, and excellent chemical resistance.

Sequence homology, amino acid, refers to the similarity in the order of amino acids in a protein or a portion of a protein between two or more species. This similarity can be used to infer evolutionary relationships and functional similarities between proteins. The higher the degree of sequence homology, the more likely it is that the proteins are related and have similar functions. Sequence homology can be determined through various methods such as pairwise alignment or multiple sequence alignment, which compare the sequences and calculate a score based on the number and type of matching amino acids.

Proteins are complex, large molecules that play critical roles in the body's functions. They are made up of amino acids, which are organic compounds that are the building blocks of proteins. Proteins are required for the structure, function, and regulation of the body's tissues and organs. They are essential for the growth, repair, and maintenance of body tissues, and they play a crucial role in many biological processes, including metabolism, immune response, and cellular signaling. Proteins can be classified into different types based on their structure and function, such as enzymes, hormones, antibodies, and structural proteins. They are found in various foods, especially animal-derived products like meat, dairy, and eggs, as well as plant-based sources like beans, nuts, and grains.

Polyacetylenes are a type of chemical compound that naturally occur in certain plants, including members of the families Asteraceae (daisies, sunflowers) and Apiaceae (carrots, parsley). They are characterized by alternating double bonds along their carbon chain, which can give them unique chemical properties. Some polyacetylenes have been found to have potential medicinal benefits, such as anti-inflammatory and anticancer effects. However, they can also be toxic in high concentrations. It's important to note that the term "polyacetylenes" refers to a broad class of compounds, and individual members may have different properties and effects.

Dendrimers are a type of synthetic, nanoscale polymer structures with a well-defined, highly branched, and regularly repeating architecture. They consist of a central core, an inner layer of repetitive branches, and an outer surface that can be functionalized with various groups. Dendrimers have unique properties such as monodispersity, a high degree of symmetry, and the ability to encapsulate or conjugate drugs, genes, and imaging agents, making them useful in drug delivery, gene therapy, diagnostics, and other biomedical applications.

A lipid bilayer is a thin membrane made up of two layers of lipid molecules, primarily phospholipids. The hydrophilic (water-loving) heads of the lipids face outwards, coming into contact with watery environments on both sides, while the hydrophobic (water-fearing) tails point inward, away from the aqueous surroundings. This unique structure allows lipid bilayers to form a stable barrier that controls the movement of molecules and ions in and out of cells and organelles, thus playing a crucial role in maintaining cellular compartmentalization and homeostasis.

Amino acids are organic compounds that serve as the building blocks of proteins. They consist of a central carbon atom, also known as the alpha carbon, which is bonded to an amino group (-NH2), a carboxyl group (-COOH), a hydrogen atom (H), and a variable side chain (R group). The R group can be composed of various combinations of atoms such as hydrogen, oxygen, sulfur, nitrogen, and carbon, which determine the unique properties of each amino acid.

There are 20 standard amino acids that are encoded by the genetic code and incorporated into proteins during translation. These include:

1. Alanine (Ala)
2. Arginine (Arg)
3. Asparagine (Asn)
4. Aspartic acid (Asp)
5. Cysteine (Cys)
6. Glutamine (Gln)
7. Glutamic acid (Glu)
8. Glycine (Gly)
9. Histidine (His)
10. Isoleucine (Ile)
11. Leucine (Leu)
12. Lysine (Lys)
13. Methionine (Met)
14. Phenylalanine (Phe)
15. Proline (Pro)
16. Serine (Ser)
17. Threonine (Thr)
18. Tryptophan (Trp)
19. Tyrosine (Tyr)
20. Valine (Val)

Additionally, there are several non-standard or modified amino acids that can be incorporated into proteins through post-translational modifications, such as hydroxylation, methylation, and phosphorylation. These modifications expand the functional diversity of proteins and play crucial roles in various cellular processes.

Amino acids are essential for numerous biological functions, including protein synthesis, enzyme catalysis, neurotransmitter production, energy metabolism, and immune response regulation. Some amino acids can be synthesized by the human body (non-essential), while others must be obtained through dietary sources (essential).

C57BL/6 (C57 Black 6) is an inbred strain of laboratory mouse that is widely used in biomedical research. The term "inbred" refers to a strain of animals where matings have been carried out between siblings or other closely related individuals for many generations, resulting in a population that is highly homozygous at most genetic loci.

The C57BL/6 strain was established in 1920 by crossing a female mouse from the dilute brown (DBA) strain with a male mouse from the black strain. The resulting offspring were then interbred for many generations to create the inbred C57BL/6 strain.

C57BL/6 mice are known for their robust health, longevity, and ease of handling, making them a popular choice for researchers. They have been used in a wide range of biomedical research areas, including studies of cancer, immunology, neuroscience, cardiovascular disease, and metabolism.

One of the most notable features of the C57BL/6 strain is its sensitivity to certain genetic modifications, such as the introduction of mutations that lead to obesity or impaired glucose tolerance. This has made it a valuable tool for studying the genetic basis of complex diseases and traits.

Overall, the C57BL/6 inbred mouse strain is an important model organism in biomedical research, providing a valuable resource for understanding the genetic and molecular mechanisms underlying human health and disease.

Opioid peptides are naturally occurring short chains of amino acids in the body that bind to opioid receptors in the brain, spinal cord, and gut, acting in a similar way to opiate drugs like morphine or heroin. They play crucial roles in pain regulation, reward systems, and addictive behaviors. Some examples of opioid peptides include endorphins, enkephalins, and dynorphins. These substances are released in response to stress, physical exertion, or injury and help modulate the perception of pain and produce feelings of pleasure or euphoria.

Intracellular signaling peptides and proteins are molecules that play a crucial role in transmitting signals within cells, which ultimately lead to changes in cell behavior or function. These signals can originate from outside the cell (extracellular) or within the cell itself. Intracellular signaling molecules include various types of peptides and proteins, such as:

1. G-protein coupled receptors (GPCRs): These are seven-transmembrane domain receptors that bind to extracellular signaling molecules like hormones, neurotransmitters, or chemokines. Upon activation, they initiate a cascade of intracellular signals through G proteins and secondary messengers.
2. Receptor tyrosine kinases (RTKs): These are transmembrane receptors that bind to growth factors, cytokines, or hormones. Activation of RTKs leads to autophosphorylation of specific tyrosine residues, creating binding sites for intracellular signaling proteins such as adapter proteins, phosphatases, and enzymes like Ras, PI3K, and Src family kinases.
3. Second messenger systems: Intracellular second messengers are small molecules that amplify and propagate signals within the cell. Examples include cyclic adenosine monophosphate (cAMP), cyclic guanosine monophosphate (cGMP), diacylglycerol (DAG), inositol triphosphate (IP3), calcium ions (Ca2+), and nitric oxide (NO). These second messengers activate or inhibit various downstream effectors, leading to changes in cellular responses.
4. Signal transduction cascades: Intracellular signaling proteins often form complex networks of interacting molecules that relay signals from the plasma membrane to the nucleus. These cascades involve kinases (protein kinases A, B, C, etc.), phosphatases, and adapter proteins, which ultimately regulate gene expression, cell cycle progression, metabolism, and other cellular processes.
5. Ubiquitination and proteasome degradation: Intracellular signaling pathways can also control protein stability by modulating ubiquitin-proteasome degradation. E3 ubiquitin ligases recognize specific substrates and conjugate them with ubiquitin molecules, targeting them for proteasomal degradation. This process regulates the abundance of key signaling proteins and contributes to signal termination or amplification.

In summary, intracellular signaling pathways involve a complex network of interacting proteins that relay signals from the plasma membrane to various cellular compartments, ultimately regulating gene expression, metabolism, and other cellular processes. Dysregulation of these pathways can contribute to disease development and progression, making them attractive targets for therapeutic intervention.

"Cattle" is a term used in the agricultural and veterinary fields to refer to domesticated animals of the genus *Bos*, primarily *Bos taurus* (European cattle) and *Bos indicus* (Zebu). These animals are often raised for meat, milk, leather, and labor. They are also known as bovines or cows (for females), bulls (intact males), and steers/bullocks (castrated males). However, in a strict medical definition, "cattle" does not apply to humans or other animals.

In the context of medical terminology, "solutions" refers to a homogeneous mixture of two or more substances, in which one substance (the solute) is uniformly distributed within another substance (the solvent). The solvent is typically the greater component of the solution and is capable of dissolving the solute.

Solutions can be classified based on the physical state of the solvent and solute. For instance, a solution in which both the solvent and solute are liquids is called a liquid solution or simply a solution. A solid solution is one where the solvent is a solid and the solute is either a gas, liquid, or solid. Similarly, a gas solution refers to a mixture where the solvent is a gas and the solute can be a gas, liquid, or solid.

In medical applications, solutions are often used as vehicles for administering medications, such as intravenous (IV) fluids, oral rehydration solutions, eye drops, and topical creams or ointments. The composition of these solutions is carefully controlled to ensure the appropriate concentration and delivery of the active ingredients.

Peptide hormones are a type of hormone consisting of short chains of amino acids known as peptides. They are produced and released by various endocrine glands and play crucial roles in regulating many physiological processes in the body, including growth and development, metabolism, stress response, and reproductive functions.

Peptide hormones exert their effects by binding to specific receptors on the surface of target cells, which triggers a series of intracellular signaling events that ultimately lead to changes in cell behavior or function. Some examples of peptide hormones include insulin, glucagon, growth hormone, prolactin, oxytocin, and vasopressin.

Peptide hormones are synthesized as larger precursor proteins called prohormones, which are cleaved by enzymes to release the active peptide hormone. They are water-soluble and cannot pass through the cell membrane, so they exert their effects through autocrine, paracrine, or endocrine mechanisms. Autocrine signaling occurs when a cell releases a hormone that binds to receptors on the same cell, while paracrine signaling involves the release of a hormone that acts on nearby cells. Endocrine signaling, on the other hand, involves the release of a hormone into the bloodstream, which then travels to distant target cells to exert its effects.

An optical device is not a medical term per se, but rather a general term that describes any instrument or tool that uses light or electromagnetic radiation in the visible spectrum to observe, measure, or manipulate objects or phenomena. However, there are several optical devices that are commonly used in medical settings and have specific medical definitions. Here are some examples:

1. Ophthalmoscope: A handheld device used by healthcare professionals to examine the interior of the eye, including the retina, optic nerve, and vitreous humor. It typically consists of a handle, a light source, and a set of lenses that can be adjusted to focus on different parts of the eye.
2. Slit lamp: A specialized microscope used in ophthalmology to examine the structures of the eye at high magnification. It uses a narrow beam of light to illuminate the eye and allows the examiner to visualize details such as corneal abrasions, cataracts, and retinal lesions.
3. Microscope: A device that uses a system of lenses or mirrors to magnify objects or images, making them visible to the human eye. Microscopes are used in various medical fields, including pathology, hematology, and microbiology, to examine specimens such as tissues, cells, and microorganisms.
4. Endoscope: A flexible tube equipped with a light source and a camera that can be inserted into body cavities or passages to visualize internal structures. Endoscopes are used in procedures such as colonoscopy, gastroscopy, and laparoscopy to diagnose and treat conditions such as polyps, ulcers, and tumors.
5. Otoscope: A device used by healthcare professionals to examine the ear canal and eardrum. It typically consists of a handle, a light source, and a speculum that can be inserted into the ear canal to visualize the eardrum and identify any abnormalities such as inflammation, infection, or foreign bodies.
6. Refractor: A device used in optometry to measure the refractive error of the eye, or the amount of lens power needed to correct vision. The patient looks through a series of lenses while reading an eye chart, and the optometrist adjusts the lenses until the clearest vision is achieved.
7. Slit lamp: A microscope used in ophthalmology to examine the structures of the eye, including the cornea, iris, lens, and retina. The slit lamp uses a narrow beam of light to illuminate the eye and allow for detailed examination of any abnormalities or diseases.

Dielectric spectroscopy is a type of material characterization technique that measures the dielectric properties of a material as a function of frequency. The dielectric property of a material refers to its ability to store electrical energy in the form of polarization when an external electric field is applied. In dielectric spectroscopy, the material's response to an alternating electric field is measured, and the resulting complex permittivity (which includes both real and imaginary components) is used to characterize the material's dielectric behavior.

The technique involves applying a small amplitude AC voltage to the material while measuring the current flow through it. The frequency of the applied voltage can be varied over a wide range, typically from millihertz to gigahertz. By analyzing the phase shift and amplitude of the resulting current, the complex permittivity of the material can be determined as a function of frequency.

Dielectric spectroscopy is widely used in materials science, physics, chemistry, and biology to study the structure, dynamics, and composition of various materials, including polymers, ceramics, glasses, colloids, and biological tissues. The technique can provide valuable information about the material's molecular mobility, relaxation processes, conductivity, and other dielectric properties, which can be used for quality control, process monitoring, and fundamental research.

I'm sorry for any confusion, but "Glass" is not a medical term. Glass is a non-crystalline amorphous solid that is often transparent and has various uses in everyday life, including medical devices and equipment. If you have any questions related to medical terminology or concepts, please provide them, and I'll be happy to help.

A lung is a pair of spongy, elastic organs in the chest that work together to enable breathing. They are responsible for taking in oxygen and expelling carbon dioxide through the process of respiration. The left lung has two lobes, while the right lung has three lobes. The lungs are protected by the ribcage and are covered by a double-layered membrane called the pleura. The trachea divides into two bronchi, which further divide into smaller bronchioles, leading to millions of tiny air sacs called alveoli, where the exchange of gases occurs.

Tertiary protein structure refers to the three-dimensional arrangement of all the elements (polypeptide chains) of a single protein molecule. It is the highest level of structural organization and results from interactions between various side chains (R groups) of the amino acids that make up the protein. These interactions, which include hydrogen bonds, ionic bonds, van der Waals forces, and disulfide bridges, give the protein its unique shape and stability, which in turn determines its function. The tertiary structure of a protein can be stabilized by various factors such as temperature, pH, and the presence of certain ions. Any changes in these factors can lead to denaturation, where the protein loses its tertiary structure and thus its function.

Temperature, in a medical context, is a measure of the degree of hotness or coldness of a body or environment. It is usually measured using a thermometer and reported in degrees Celsius (°C), degrees Fahrenheit (°F), or kelvin (K). In the human body, normal core temperature ranges from about 36.5-37.5°C (97.7-99.5°F) when measured rectally, and can vary slightly depending on factors such as time of day, physical activity, and menstrual cycle. Elevated body temperature is a common sign of infection or inflammation, while abnormally low body temperature can indicate hypothermia or other medical conditions.

A cell membrane, also known as the plasma membrane, is a thin semi-permeable phospholipid bilayer that surrounds all cells in animals, plants, and microorganisms. It functions as a barrier to control the movement of substances in and out of the cell, allowing necessary molecules such as nutrients, oxygen, and signaling molecules to enter while keeping out harmful substances and waste products. The cell membrane is composed mainly of phospholipids, which have hydrophilic (water-loving) heads and hydrophobic (water-fearing) tails. This unique structure allows the membrane to be flexible and fluid, yet selectively permeable. Additionally, various proteins are embedded in the membrane that serve as channels, pumps, receptors, and enzymes, contributing to the cell's overall functionality and communication with its environment.

Organosilicon compounds are a class of chemical compounds that contain at least one organic group (a group of atoms composed mainly of carbon and hydrogen) bonded to a silicon atom. The organic group can be an alkyl group, aryl group, or any other group that is derived from a hydrocarbon.

The term "organosilicon" is used to describe the covalent bond between carbon and silicon atoms, which is a type of bond known as a "sigma bond." This bond is formed by the overlap of atomic orbitals between the carbon and silicon atoms. The resulting organosilicon compound can have a wide range of physical and chemical properties, depending on the nature of the organic group and the number of such groups attached to the silicon atom.

Organosilicon compounds are widely used in various industries, including electronics, coatings, adhesives, and pharmaceuticals. They are also used as intermediates in the synthesis of other chemical compounds. Some common examples of organosilicon compounds include silicones, which are polymers that contain repeating units of siloxane (Si-O-Si) bonds, and organofunctional silanes, which are used as coupling agents to improve the adhesion of materials to surfaces.

Recombinant proteins are artificially created proteins produced through the use of recombinant DNA technology. This process involves combining DNA molecules from different sources to create a new set of genes that encode for a specific protein. The resulting recombinant protein can then be expressed, purified, and used for various applications in research, medicine, and industry.

Recombinant proteins are widely used in biomedical research to study protein function, structure, and interactions. They are also used in the development of diagnostic tests, vaccines, and therapeutic drugs. For example, recombinant insulin is a common treatment for diabetes, while recombinant human growth hormone is used to treat growth disorders.

The production of recombinant proteins typically involves the use of host cells, such as bacteria, yeast, or mammalian cells, which are engineered to express the desired protein. The host cells are transformed with a plasmid vector containing the gene of interest, along with regulatory elements that control its expression. Once the host cells are cultured and the protein is expressed, it can be purified using various chromatography techniques.

Overall, recombinant proteins have revolutionized many areas of biology and medicine, enabling researchers to study and manipulate proteins in ways that were previously impossible.

Physicochemical processes refer to interactions and changes that occur at the interface of physical and chemical systems in a living organism or biological sample. These processes are crucial in understanding various biological phenomena, including cellular functions, metabolic pathways, and drug actions. They involve the transformation of energy and matter, as well as the formation and breaking of chemical bonds.

Examples of physicochemical processes include:

1. Membrane transport: The movement of molecules across biological membranes through passive diffusion or active transport.
2. Enzyme kinetics: The study of how enzymes catalyze biochemical reactions, including the rate of reaction and the factors that affect it.
3. Protein folding: The process by which a protein molecule assumes its three-dimensional structure, which is critical for its function.
4. Acid-base equilibria: The balance between acids and bases in biological systems, which affects various physiological processes such as pH regulation.
5. Oxidation-reduction reactions: The transfer of electrons between molecules, which plays a crucial role in energy metabolism and other cellular functions.
6. Conformational changes: The alterations in the shape or structure of biological macromolecules, such as proteins and nucleic acids, that are critical for their function.
7. Phase transitions: The transformation of matter from one physical state to another, such as the melting of lipid membranes or the denaturation of proteins.

Understanding physicochemical processes is essential in developing medical interventions, including drugs and therapies, as well as in diagnosing and treating various diseases.

A chemical model is a simplified representation or description of a chemical system, based on the laws of chemistry and physics. It is used to explain and predict the behavior of chemicals and chemical reactions. Chemical models can take many forms, including mathematical equations, diagrams, and computer simulations. They are often used in research, education, and industry to understand complex chemical processes and develop new products and technologies.

For example, a chemical model might be used to describe the way that atoms and molecules interact in a particular reaction, or to predict the properties of a new material. Chemical models can also be used to study the behavior of chemicals at the molecular level, such as how they bind to each other or how they are affected by changes in temperature or pressure.

It is important to note that chemical models are simplifications of reality and may not always accurately represent every aspect of a chemical system. They should be used with caution and validated against experimental data whenever possible.

A nanocapsule is a type of nanoparticle that is characterized by its hollow, spherical structure. It is composed of a polymeric membrane that encapsulates an inner core or "cargo" which can be made up of various substances such as drugs, proteins, or imaging agents. The small size of nanocapsules (typically ranging from 10 to 1000 nanometers in diameter) allows them to penetrate cells and tissue more efficiently than larger particles, making them useful for targeted drug delivery and diagnostic applications.

The polymeric membrane can be designed to be biodegradable or non-biodegradable, depending on the desired application. Additionally, the surface of nanocapsules can be functionalized with various moieties such as antibodies, peptides, or small molecules to enhance their targeting capabilities and improve their stability in biological environments.

Overall, nanocapsules have great potential for use in a variety of medical applications, including cancer therapy, gene delivery, and vaccine development.

Molecular cloning is a laboratory technique used to create multiple copies of a specific DNA sequence. This process involves several steps:

1. Isolation: The first step in molecular cloning is to isolate the DNA sequence of interest from the rest of the genomic DNA. This can be done using various methods such as PCR (polymerase chain reaction), restriction enzymes, or hybridization.
2. Vector construction: Once the DNA sequence of interest has been isolated, it must be inserted into a vector, which is a small circular DNA molecule that can replicate independently in a host cell. Common vectors used in molecular cloning include plasmids and phages.
3. Transformation: The constructed vector is then introduced into a host cell, usually a bacterial or yeast cell, through a process called transformation. This can be done using various methods such as electroporation or chemical transformation.
4. Selection: After transformation, the host cells are grown in selective media that allow only those cells containing the vector to grow. This ensures that the DNA sequence of interest has been successfully cloned into the vector.
5. Amplification: Once the host cells have been selected, they can be grown in large quantities to amplify the number of copies of the cloned DNA sequence.

Molecular cloning is a powerful tool in molecular biology and has numerous applications, including the production of recombinant proteins, gene therapy, functional analysis of genes, and genetic engineering.

I'm sorry for any confusion, but "thermodynamics" is not a term that has a specific medical definition. It is a branch of physics that deals with the relationships between heat and other forms of energy. However, the principles of thermodynamics can be applied to biological systems, including those in the human body, such as in the study of metabolism or muscle function. But in a medical context, "thermodynamics" would not be a term used independently as a diagnosis, treatment, or any medical condition.

Photoelectron Spectroscopy (PES) is not typically considered a medical definition, but it is a term used in physical and analytical chemistry. However, I can provide a definition for you:

Photoelectron Spectroscopy (PES) is a technique used to study the electronic structure of atoms, molecules, and solids by irradiating them with photons (usually from a laser or a synchrotron light source) and measuring the kinetic energy of the ejected electrons. The technique provides information about the energy levels of the electrons in the sample, which can be used to determine its chemical composition, bonding, and electronic structure. PES is a valuable tool in surface science, materials research, and environmental analysis.

Thermal conductivity is not a term that has a specific medical definition. It is a physical property of materials that refers to their ability to conduct heat. However, in the context of medicine, thermal conductivity may be relevant when discussing certain medical treatments or devices that involve heating or cooling tissues. For example, some ablation techniques used to destroy cancerous tissue use probes with high thermal conductivity to deliver radiofrequency energy and generate heat.

Here is a general definition of thermal conductivity:

Thermal conductivity (k) is the measure of a material's ability to transfer heat energy conducted through it due to a temperature difference. It is expressed as the amount of heat energy (in watts, W) transferred per unit of time (second, s) through a unit area (square meter, m²) with a given temperature difference (kelvin, K) between the two faces. The formula for thermal conductivity is:

k = Q x L / (A x ΔT)

Where:

* k is the thermal conductivity (in W/mK)
* Q is the heat transfer rate (in watts, W)
* L is the length of the material through which the heat is transferred (in meters, m)
* A is the cross-sectional area of the material perpendicular to the heat flow (in square meters, m²)
* ΔT is the temperature difference between the two faces of the material (in kelvin, K)

Substrate specificity in the context of medical biochemistry and enzymology refers to the ability of an enzyme to selectively bind and catalyze a chemical reaction with a particular substrate (or a group of similar substrates) while discriminating against other molecules that are not substrates. This specificity arises from the three-dimensional structure of the enzyme, which has evolved to match the shape, charge distribution, and functional groups of its physiological substrate(s).

Substrate specificity is a fundamental property of enzymes that enables them to carry out highly selective chemical transformations in the complex cellular environment. The active site of an enzyme, where the catalysis takes place, has a unique conformation that complements the shape and charge distribution of its substrate(s). This ensures efficient recognition, binding, and conversion of the substrate into the desired product while minimizing unwanted side reactions with other molecules.

Substrate specificity can be categorized as:

1. Absolute specificity: An enzyme that can only act on a single substrate or a very narrow group of structurally related substrates, showing no activity towards any other molecule.
2. Group specificity: An enzyme that prefers to act on a particular functional group or class of compounds but can still accommodate minor structural variations within the substrate.
3. Broad or promiscuous specificity: An enzyme that can act on a wide range of structurally diverse substrates, albeit with varying catalytic efficiencies.

Understanding substrate specificity is crucial for elucidating enzymatic mechanisms, designing drugs that target specific enzymes or pathways, and developing biotechnological applications that rely on the controlled manipulation of enzyme activities.

Acute toxicity tests are a category of medical or biological testing that measure the short-term adverse effects of a substance on living organisms. These tests are typically performed in a laboratory setting and involve exposing test subjects (such as cells, animals, or isolated organs) to a single high dose or multiple doses of a substance within a short period of time, usually 24 hours or less.

The primary objective of acute toxicity testing is to determine the median lethal dose (LD50) or concentration (LC50) of a substance, which is the amount or concentration that causes death in 50% of the test subjects. This information can be used to help assess the potential health hazards associated with exposure to a particular substance and to establish safety guidelines for its handling and use.

Acute toxicity tests are required by regulatory agencies around the world as part of the process of evaluating the safety of chemicals, drugs, and other substances. However, there is growing concern about the ethical implications of using animals in these tests, and many researchers are working to develop alternative testing methods that do not involve the use of live animals.

Pharmaceutical Formulation of Peptide Nanotubes for Drug Delivery Applications.. Garry Laverty, Simon Porter, Sophie Coulter, ... Pharmaceutical Formulation of Peptide Nanotubes for Drug Delivery Applications. / Laverty, Garry; Porter, Simon; Coulter, ... Pharmaceutical Formulation of Peptide Nanotubes for Drug Delivery Applications. Paper presented at Controlled Release Society ... Laverty G, Porter S, Coulter S, Pentlavalli S. Pharmaceutical Formulation of Peptide Nanotubes for Drug Delivery Applications. ...
NANOTUBES formed from cyclic peptides (PEPTIDES, CYCLIC). Alternating D and L linkages create planar rings that self assemble ... Peptide" by people in UAMS Profiles by year, and whether "Nanotubes, Peptide" was a major or minor topic of these publications ... "Nanotubes, Peptide" is a descriptor in the National Library of Medicines controlled vocabulary thesaurus, MeSH (Medical ... Below are the most recent publications written about "Nanotubes, Peptide" by people in Profiles over the past ten years. ...
Self-assembling peptide nanotubes 10 June 2008. Novel nanostructures for SERS biosensing 10 June 2008 ...
However, there is an urgent need for the further in vivo nanotoxicity and safety testing of these nanotubes to evaluate their ... Self-assembled cyclic peptide nanotubes (cPNTs) have recently drawn particular attention as one of the most intriguing ... Self-assembled cyclic peptide nanotubes (cPNTs) have recently drawn particular attention as one of the most intriguing ... Hsieh, W.-H. and Liaw, J. (2019) "Applications of cyclic peptide nanotubes (cPNTs)," Journal of Food and Drug Analysis: Vol. 27 ...
The simplest peptide building blocks are dipeptides. Nanotubes formed from dipeptides are the widest among peptide nanotubes. ... The samples also showed a dynamic behaviours and some vesicles "buds" out of the peptide nanotubes. This class of peptides ... Nanotubes formed from dipeptides are stable under extreme conditions. Dry nanotubes do not degrade until 200 °C; nanotubes ... a cell-based therapy approach is needed and peptides could potentially play a huge role in this. Cyclic peptide nanotubes ...
Controlling the Physical Dimensions of Peptide Nanotube by Supramolecular Polymer Co-assembly ACS Nano. 10(8), 7436-7442 ... Surface-templated fibril growth of peptide fragments from the shaft domain of the adenovirus fibre protein. Protein and peptide ... Chemical vapor deposition growth of carbon nanotubes on Si substrates using Fe catalyst: What happens at the nanotube/Fe/Si ... Controlling the Physical Dimensions of Peptide Nanotube by Supramolecular Polymer Co-assembly ACS Nano. (In Press.) ...
A. Czajlik; T. Beke; A. Bottoni; A. Perczel, Structure and Stability of Short β-Peptide Nanotubes: A Non-Natural ...
We report the observation of intermediate structures in the self-assembly of the peptide KFE8 (FKFEFKFE), designed with ... Twisted Nanotubes Formed from Ultrashort Amphiphilic Peptide I3K and Their Templating for the Fabrication of Silica Nanotubes. ... Self-assembly of Surfactant-like Peptides with Variable Glycine Tails to Form Nanotubes and Nanovesicles. Nano Letters 2002, 2 ... MaP Peptides: Programming the Self-Assembly of Peptide-Based Mesoscopic Matrices. Journal of the American Chemical Society 2005 ...
We determine nine polymorphic crystal structures of the APR segments of glucagon-like peptides 1 and 2, and exendin and its ... of gastrointestinal peptides of the glucagon family: xFxxWL. ... The fibrils or nanotubes composed of β-sheets28 had a linear, ... PRP PACAP-related peptide, PHI peptide histidine isoleucine, PHM: peptide histidine methionine, VIP vasoactive intestinal ... Stock solutions with a peptide concentration of 0.5 mM were prepared as follows: peptides were dissolved in water with pH 7.4 ...
Carbon nanotubes (CNTs) are increasingly being used in electronics products. CNTs have unique chemical and nanotoxicological ... Self-assembling organic nanotubes based on a cyclic peptide architecture. Nature 1993, 366, 324-327. [Google Scholar] [CrossRef ... CNTs are subdivided into two main classes, single walled carbon nano tubes (SWCNT) and multi-walled carbon nano tubes (MWCNT). ... Ajayan, P.M.; Stephan, O.; Colliex, C.; Trauth, D. Aligned carbon nanotube arrays formed by cutting a polymer resin--nanotube ...
FIGURE 1: A vision of a nano-organism: carbon nanotubes form the main body; peptide limbs can be used for locomotion and object ... Carbon-Nanotubes and their Interface With VPL Motors and DNA. Bernard Yurke, Ph.D.. Senior Collaborator. Senior Research ... DNA Joints and their Interface With Carbon-Nanotubes. Atul Dubey. Research Assistant. Graduate Student, Department of ... Figure 1 shows one such concept of a nano-organism, with its feet made of helical peptides, and its body using carbon ...
Identified MWCNT-responsive peptides depicted a mechanism involving aberrant fibrinolysis in connection with blood-brain ... Weve previously demonstrated a link between nanomaterial exposure, specifically multiwalled carbon nanotube (MWCNT), and serum ... Using our in-lab developed software, EndogeSeq, we identified 27 of the 104 most-discriminant peptides in the serum of 24 ... Peptide compilation was functionally related to pulmonary injury, vascular dysfunction, altered translation, and autophagy/ ...
Peptide and peptide-carbon nanotube hydrogels as scaffolds for tissue & 3D tumor engineering  Sheikholeslam, Mohammadali; ... Peptide and peptide-carbon nanotube hydrogels as scaffolds for tissue & 3D tumor engineering  Sheikholeslam, Mohammadali; ... The use of hybrid self-assembling peptide (EFK8)-carbon nanotube (SWNT) hydrogels for tissue engineering and in vitro 3D cancer ... The use of hybrid self-assembling peptide (EFK8)-carbon nanotube (SWNT) hydrogels for tissue engineering and in vitro 3D cancer ...
Tunable synthesis of self-assembled cyclic peptide nanotubes and nanoparticles. Leming Sun, Zhen Fan, Yongzhong Wang, Yujian ... Surfactant-induced assembly of enzymatically-stable peptide hydrogels. Brad H. Jones, Alina M. Martinez, Jill S. Wheeler and ...
Casting metal nanowires within discrete self-assembled peptide nanotubes. Science. 2003 Apr 25;300(5619):625-7. PubMed. ... If you cant solve the Fab/peptide structure by crystallography, you can get information about the bound peptide conformation ... The peptide is about 95 percent homogeneous. The rabbit has been boosted over 20 times now and we dont see normal Ab ... Id like to call on all to check out last Fridays Science paper on nanotubes and nanowires made of Ab dipeptide (Reches and ...
MATS004 - Peptide Nanotubes: Redesigning Amyloid-B as a Metalloprotein. Ryan Sung Han, 17, The Gwinnett School of Math, Science ... TMED007 - The Effect of Spermidine on β-Amyloid Peptide Toxicity in C. elegans: A Model System for Understanding Alzheimers ... BMED057 - Caerin 1.9: A Possible Treatment for Alzheimers Disease? Investigating the Effects of the Caerin 1.9 Peptide on ... Engineering a Broad-Spectrum Antibacterial Probiotic via Inclusion of Antimicrobial Peptide-Encoding DNA, Year Two ...
Scientists have discovered that the strong force field emitted by a Tesla coil causes carbon nanotubes to self-assemble into ... A new method for peptide sequencing based on nanopore sensing technology. Nov 24, 2023 ... "These nanotube wires grow and act like nerves, and controlled assembly of nanomaterials from the bottom up may be used as a ... Carbon nanotubes in a dish assemble themselves into a nanowire in seconds under the influence of a custom-built Tesla coil ...
Work during my studies in Leiden focused on developing solid oral dosage forms for the oral delivery peptide drugs with TMC. I ... The use of carbon nanotubes in drug delivery and clinical assays.. *The application of electro-spraying and -spinning in drug ... Jungingers laboratory was world renowned for the work done in the delivery of peptide drugs with various mucosal absorption ... a mucosal absorption enhancer used in the delivery of peptide drugs. ...
It turns out that biological materials such as bones, collagen, and peptide nanotubes can generate electricity in response to ...
The Janus nanotubes have a tubular structure based on the stacking of cyclic peptides, which provide a tube with a channel of ... The study, Janus cyclic peptide-polymer nanotubes, was authored by Maarten Danial, Carmen My-Nhi Tran, Philip G. Young, ... "Janus nanotubes are a versatile platform for the design of exciting materials which have a wide range of application, from ... Attached to each of the cyclic peptides are two different types of polymers, which tend to de-mix and form a shell for the tube ...
Reversible transitions between peptide nanotubes and vesicle-like structures including theoretical modeling studies. Chemistry ... Yan, X. H.; Cui, Y.; He, Q.; Wang, K. W.; Li, J. B.; Li, J. B.: Organogels based on self-assembly of diphenylalanine peptide ... He, Q.; Tian, Y.; Cui, Y.; Möhwald, H.; Li, J. B.: Layer-by-layer assembly of magnetic polypeptide nanotubes as a DNA carrier. ... Yan, X. H.; Cui, Y.; Qi, W.; Su, Y.; Yang, Y.; He, Q.; Li, J. B.: Self-assembly of peptide-based colloids containing lipophilic ...
review the design and synthesis of carbon nanotube segments. How can nanotubes be synthesized in a controlled way, with single ... chirality, and through organic template-assisted growth? In a Minireview, J. Wan and P. F. Alewood discuss peptide-decorated ...
The study is "Peptide secondary structure modulates single-walled carbon nanotube fluorescence as a chaperone sensor for ...
Stability of diphenylalanine peptide nanotubes in solution. Andersen, K. B., Castillo-Leon, J., Hedström, M. & Svendsen, W. E. ... Development of a real-time capacitive biosensor for cyclic cyanotoxic peptides based on Adda-specific antibodies.. Lebogang, L. ... Mass spectrometric analysis of peptides from an immobilized lipase: focus on oxidative modifications.. Törnvall, U., Melin ...
Microwave-enhanced Solid-phase Peptide Synthesis 21. Application of Microwave Irradiation in Fullerene and Carbon Nanotube ... solid phase peptide synthesis, carbon nanotubes and fullerenes. The standard reference in this booming field. ... Lab-on-a-Chip.com , MassSpec.net , Metabolomics.net , MicrowaveSynthesis.net , NanoTechnology.net , Peptides.net , ...
Such an event has been used to design polyvalent nanotube-peptide conjugates that target and destroy anthrax toxin and to ... These solubilized nanotube-protein complexes may have application in the selective assembly of nanotubes for biological, ... Carbon Nanotube Based Gas Sensor Based on MWNT Arrays. Figures 30 and 31 show recent collaborative work in the NSEC (Ajayan, ... Here the nanotubes concentrate the electric field at their tiny tips and hence bring down (several fold, for example, from ~ ...
Above: (A) molecular model of one such peptide; (B) cut-away model of a nanotube formed from the peptide, and (C) an actual ... In (B), blue corresponds to the peptides positively charged heads; green, the water-averse tails. The peptides assemble so the ... He is focusing on one material, cationic peptide surfactants.. There are two rules governing the behavior of this new class of ... Once inside the cell, the peptides would be broken down in the cells higher-pH environment and their amino acids reused. The ...
... activity and cytocompatibility of an implant coating consisting of TiO2 nanotubes combined with a GL13K antimicrobial peptide. ... 46] Antimicrobial peptide coatings, besides their direct action against microorganisms, may also exert an immune-regulatory ... 2, 3] Titanium oxide nanotube structures increase surface area, thereby improving macrophage adhesion. Electrospun fibers ...
Protease-Resistant and Cell-Permeable Double-Stapled Peptides Targeting the Rab8a GTPase. Cromm PM, et al. ACS Chem Biol, 2016 ... Intercellular transfer of transferrin receptor by a contact-, Rab8-dependent mechanism involving tunneling nanotubes. Burtey A ...
  • this gives the peptides an edge over carbon nanotubes, which are another popular nanomaterial, as the carbon structure is unreactive. (wikipedia.org)
  • Carbon nanotubes (CNTs) are increasingly being used in electronics products. (mdpi.com)
  • e) To study the interface of the proposed protein motors and sensors with other biomolecular components such as DNA joints and carbon-nanotube rigid links so that complex, multi-degree of freedom machines and robots are formed. (nanotech-now.com)
  • We've previously demonstrated a link between nanomaterial exposure, specifically multiwalled carbon nanotube (MWCNT), and serum compositional changes that promote inflammatory pathways and vascular dysfunction. (cdc.gov)
  • The use of hybrid self-assembling peptide (EFK8)-carbon nanotube (SWNT) hydrogels for tissue engineering and in vitro 3D cancer spheroid formation is reported. (uwaterloo.ca)
  • Nanowerk News ) Scientists at Rice University have discovered that the strong force field emitted by a Tesla coil causes carbon nanotubes to self-assemble into long wires, a phenomenon they call "Teslaphoresis. (nanowerk.com)
  • The team led by Rice chemist Paul Cherukuri reported its results this week in ACS Nano ( 'Teslaphoresis of Carbon Nanotubes' ). (nanowerk.com)
  • Carbon nanotubes in a dish assemble themselves into a nanowire in seconds under the influence of a custom-built Tesla coil created by scientists at Rice University. (nanowerk.com)
  • The use of carbon nanotubes in drug delivery and clinical assays. (port.ac.uk)
  • of carbon nanotube segments . (chemistryviews.org)
  • The study is "Peptide secondary structure modulates single-walled carbon nanotube fluorescence as a chaperone sensor for nitroaromatics", PNAS 2011 : 1005512108v1-6. (improbable.com)
  • The addition of new chapters means this new edition has 30% more content, including such topics as ionic liquids, carbohydrate chemistry, multicomponent reactions, solid phase peptide synthesis, carbon nanotubes and fullerenes. (combichem.net)
  • Specifically, microcapsules have been synthesized in which single-wall carbon nanotubes (SWNTs) suspended in organic solvents are encapsulated. (rpi.edu)
  • Over 90 percent of the device is cellulose that has been infused with aligned carbon nanotubes that act as electrodes and enable electrical conduction. (rpi.edu)
  • Carbon Nanotubes (CNTs) are newly developed biocompatible materials that can be designed to deliver anticancer agents by functionalizing the CNTs with drugs. (eurekaselect.com)
  • Resende, R.R. Carbon nanotube interaction with extracellular matrix proteins producing scaffolds for tissue engineering. (eurekaselect.com)
  • Carbon nanotubes (CNTs) can be filled with a wide range of inorganic materials, and thus can be used as 'contrast agents' if biologically absent elements are encapsulated. (icmab.es)
  • Researchers in Japan have now succeeded for the first time in observing a long chain of a fullerene-labeled hydrocarbon passing through a nanometer-size pore in the wall of a carbon nanotube as if it were alive. (nanowerk.com)
  • We used imaging with a transmission electron microscope to observe the structure and orientation of a hydrocarbon chain as it passes through nanoscale defects in the walls of a single-walled carbon nanotube and also to study the interactions between the chain and the nanopore' Dr. Eiichi Nakamura tells Nanowerk. (nanowerk.com)
  • By further close observation of each molecule, we also succeeded in observing the phenomenon of the string-like molecule passing through the pore in the wall of a carbon nanotube. (nanowerk.com)
  • Already last year, Nakamura and his team at the University of Tokyo reported in Science that when boron-atom-labeled organic molecules were confined in carbon nanotubes and observed by a transmission electron microscope (TEM), conformation and movement of each molecule could be observed as moving images ( 'Imaging of Single Organic Molecules in Motion' ). (nanowerk.com)
  • Organic molecules passing through a pore in the wall of carbon nanotube. (nanowerk.com)
  • We also found that the velocity of movement and the life of observed molecules are not greatly different, whether they are inside or outside of the carbon nanotube. (nanowerk.com)
  • The latter conclusion coincides with the group's recently reported result that biomolecules having peptides bonded to the outside of carbon nanotubes can be stably observed ( 'Imaging of Conformational Changes of Biotinylated Triamide Molecules Covalently Bonded to a Carbon Nanotube Surface' ). (nanowerk.com)
  • One practical application of this could be the study of the mechanism of gas absorption and separation using carbon nanotubes or graphitic materials. (nanowerk.com)
  • Self-assembly of carbon nanotubes and antibodies on tumours for targeted amplified delivery. (mskcc.org)
  • Workplace exposure assessment of BNNT from two manufacturing facilities measured boron concentrations in personal breathing zones from non-detectable to 0.95g/m3 and TEM structure counts of 0.0123 0.0094 structures/cm3, concentrations well below what was found with other engineered high aspect ratio nanomaterials like carbon nanotubes and nanofibers. (cdc.gov)
  • NANOTUBES formed from cyclic peptides (PEPTIDES, CYCLIC). (uams.edu)
  • The Janus nanotubes have a tubular structure based on the stacking of cyclic peptides, which provide a tube with a channel of around 1nm (around one millionth of a mm) - the right size to allow small molecules and ions to pass through. (warwick.ac.uk)
  • Attached to each of the cyclic peptides are two different types of polymers, which tend to de-mix and form a shell for the tube with two faces - hence the name Janus nanotubes. (warwick.ac.uk)
  • Through a process of molecular engineering - a bit like molecular Lego - we have assembled the nanotubes from two types of building blocks - cyclic peptides and polymers. (warwick.ac.uk)
  • The supramolecular stacking of cyclic peptides is a versatile approach for the formation of nanotubes. (sfnano.fr)
  • For this purpose, biocompatible polymers will be conjugated to cyclic peptides and the self-assembly capacity of the polymer-peptide conjugates will be assessed. (sfnano.fr)
  • 25/08/2020 - Our second paper on 2D supramolecular materials based on cyclic peptides is out. (javiermontenegrochemistry.com)
  • The supramolecular polymerization of cyclic peptides at the core or the cortex of water microdroplets is regulated under microfluidic control of pH and ionic strength. (javiermontenegrochemistry.com)
  • Self-assembling peptides are a category of peptides which undergo spontaneous assembling into ordered nanostructures. (wikipedia.org)
  • Here we show that sealed single-walled CNTs filled with lead, barium and even krypton can be produced, and externally decorated with peptides to provide affinity for sub-cellular targets. (icmab.es)
  • The reason why Peter Lansbury and others used the term 'natively unfolded' for a-synuclein and other proteins, especially peptides, is that they do not exist, to a significant degree, in the same kind of stable structure that larger native proteins like myoglobin do. (alzforum.org)
  • Our work has created a new type of material - nanotubes - which can be used to replace these channel processes and can be controlled with a much higher level of accuracy than natural channel proteins. (warwick.ac.uk)
  • Nakamura expects that scientists will soon be able to freely observe, molecule by molecule, the movements of various molecules such as proteins and DNAs fixed outside of nanotubes. (nanowerk.com)
  • In this talk I will introduce the work we do in my research group involving nanostructured surfaces, nanoparticles, nanopillars and nanotubes for use in bio-analytical applications. (lu.se)
  • Peptide synthesis can be easily conducted by the established method of solid-phase chemistry in grams or kilogram quantities. (wikipedia.org)
  • The d-isomer conformation can be used for peptide synthesis. (wikipedia.org)
  • In this context, this project is centered on the synthesis of length-controlled polymer-peptide hybrid nanotubes as carriers for the delivery of an anticancer drug. (sfnano.fr)
  • The candidate must have a PhD with a strong a background in organic synthesis, in particular peptide synthesis. (sfnano.fr)
  • The ability of peptides to perform self-assembly allows them to be used as fabrication tools, which is currently and will continue to grow as a fundamental part of nanomaterials production. (wikipedia.org)
  • These nanotube wires grow and act like nerves, and controlled assembly of nanomaterials from the bottom up may be used as a template for applications in regenerative medicine," Bornhoeft said. (nanowerk.com)
  • Organic nanotubes are promising nanomaterials displaying many applications in nanotechnology, in particular in nanomedicine. (sfnano.fr)
  • In the May 13 issue of the journal Langmuir, von Maltzahn and colleagues report the first characterization of one such material, cationic peptide surfactants. (mit.edu)
  • He is focusing on one material, cationic peptide surfactants. (mit.edu)
  • These hydrogen bonds bind peptide chains together to give rise to secondary structures. (wikipedia.org)
  • The type of interactions that occur to reassemble peptide structures include van der Waals forces, ionic bonds, hydrogen bonds, and hydrophobic forces. (wikipedia.org)
  • We report the observation of intermediate structures in the self-assembly of the peptide KFE8 (FKFEFKFE), designed with alternating polar and nonpolar amino acids. (acs.org)
  • We determine nine polymorphic crystal structures of the APR segments of glucagon-like peptides 1 and 2, and exendin and its derivatives. (nature.com)
  • Reversible transitions between peptide nanotubes and vesicle-like structures including theoretical modeling studies. (mpg.de)
  • MIT undergraduate Geoffrey von Maltzahn, below, has explored a material, or peptide, that could self-assemble into structures like tiny spheres or tubes. (mit.edu)
  • The peptides form structures (nanotubes, nanovesicles and membranes) with their heads as the outer surface and their tails protected within. (mit.edu)
  • Originally described in 1993, these designer peptides have attracted interest in the field of nanotechnology for their potential for application in areas such as biomedical nanotechnology, tissue cell culturing, molecular electronics, and more. (wikipedia.org)
  • Peptide nanotubes are a class of organic nanotubes attracting immense interest due their wide range of bio- (and other) functionalities, which leads to many potential use in nanotechnology and biomedicine. (sfnano.fr)
  • Organogels based on self-assembly of diphenylalanine peptide and their application to immobilize quantum dots. (mpg.de)
  • Peptide Nanotubes: A Non-Natural Representative of Collagen? (unibo.it)
  • It turns out that biological materials such as bones, collagen, and peptide nanotubes can generate electricity in response to pressure. (electronicdesign.com)
  • Janus nanotubes are a versatile platform for the design of exciting materials which have a wide range of application, from membranes - for instance for the purification of water, to therapeutic uses, for the development of new drug systems. (warwick.ac.uk)
  • The second, but not the last, paper with @WernerNau 🇩🇪🤝🇪🇸on #chaotropiccarriers COSANs Boron Sandwiches 🥪for the transport of peptides across membranes and inside cells! (javiermontenegrochemistry.com)
  • They link together in a controlled manner to form short peptides, which link to form long polypeptide chains. (wikipedia.org)
  • Layer-by-layer assembly of magnetic polypeptide nanotubes as a DNA carrier. (mpg.de)
  • Hydrothermal-induced structure transformation of polyelectrolyte multilayers: from nanotubes to capsules. (mpg.de)
  • Each hormone peptide has its own class B type G-protein coupled receptor 19 , 21 functioning along identical receptor activating schemes (Fig. 1c ). (nature.com)
  • See also David Thirumalai's Emerging Ideas on the Molecular Basis of Protein and Peptide Aggregation ' (.pdf). (alzforum.org)
  • Multiwall nanotubes with a diameter of 80-300 nm, made of dipeptides from the diphenylalanine motif of Alzheimer's β-amyloid peptide are made by this method. (wikipedia.org)
  • The self-assembly process of the peptide chains is dynamic-reassembly occurs repeatedly in a self-healing manner. (wikipedia.org)
  • Self-Assembly of Block Heterochiral Peptides into Helical Tapes. (acs.org)
  • Self-assembly of composite nanotubes and their applications. (mpg.de)
  • Self-assembly of peptide-based colloids containing lipophilic nanocrystals. (mpg.de)
  • This facilitates the wide range of chemical interactions and, therefore, molecular recognitions that peptides are capable of, for designer self-assembling peptides, both natural and non-natural amino acids are used. (wikipedia.org)
  • These forces also facilitate the molecular recognition function that the peptides encompasses. (wikipedia.org)
  • Using a process which they liken to molecular Lego, scientists from the University of Warwick and the University of Sydney have created what they have named 'Janus nanotubes' - very small tubes with two distinct faces. (warwick.ac.uk)
  • Identified MWCNT-responsive peptides depicted a mechanism involving aberrant fibrinolysis in connection with blood-brain barrier permeation, astrocyte and microglial reactivity with dose-dependent differences and a pro-degradative anti-plastic hyperexcited state. (cdc.gov)
  • The research for my MSc focused on investigating the in vitro toxicity profile of N-trimethyl chitosan chloride (TMC), a mucosal absorption enhancer used in the delivery of peptide drugs. (port.ac.uk)
  • Prof. Junginger's laboratory was world renowned for the work done in the delivery of peptide drugs with various mucosal absorption enhancers as well as mucosal vaccination. (port.ac.uk)
  • Work during my studies in Leiden focused on developing solid oral dosage forms for the oral delivery peptide drugs with TMC. (port.ac.uk)
  • Prolonged survival in acute myeloid leukemia with galinpepimut-S, a WT1 peptide vaccine, given after achievement of CR1. (mskcc.org)
  • After many years of optimization of our peptide amphiphiles' tranfection performance it will be put to the test for the development of a Spanish vaccine against COVID-19. (javiermontenegrochemistry.com)
  • Nanotube assemblies are drawn to the source of a Tesla field in an experiment at a Rice University lab. (nanowerk.com)
  • How can nanotubes be synthesized in a controlled way, with single chirality, and through organic template-assisted growth? (chemistryviews.org)
  • Binding Mechanisms of Amyloid-like Peptides to Lipid Bilayers and Effects of Divalent Cations. (acs.org)
  • When the attraction of the positively charged heads to a negatively charged surface like DNA is added to this process, the peptide heads surround and compact the DNA. (mit.edu)
  • The presence of the polymer chains will put strain on the peptide core through steric repulsions, allowing to reduce the length of the nanotubes and enable their use as carriers of an anticancer drug. (sfnano.fr)
  • Pharmaceutical Formulation of Peptide Nanotubes for Drug Delivery Applications. (qub.ac.uk)
  • Effectively self-assembling peptides act as building blocks for various material and device applications. (wikipedia.org)
  • 6/6/23 Check out our New Paper @J_A_C_S in collaboration with Nuno Basilio on photoswitchable calixarene carriers for peptide transport. (javiermontenegrochemistry.com)
  • The primary structure of a peptide is the sequence of the amino acids on the peptide chain. (wikipedia.org)
  • Peptide-Membrane Binding: Effects of the Amino Acid Sequence. (acs.org)
  • The self-assembling of peptides is facilitated through the molecules' structural and chemical compatibility with each other. (wikipedia.org)
  • The inhibition of one of these steps by small molecules, such as antimicrobial peptides, or their action on specific targets will leave pathogens armless against classical antibiotics. (intechopen.com)
  • The peptide structure is organized hierarchically into four levels. (wikipedia.org)
  • B) cut-away model of a nanotube formed from the peptide, and (C) an actual image of a structure formed by the peptide. (mit.edu)
  • Nanotubes were a natural first test material, given their heritage at Rice, where the HiPco production process was invented. (nanowerk.com)
  • The toxicity of boron nitride nanotubes (BNNTs) has been the subject of conflicting reports, likely due to differences in the residuals and impurities that can make up to 30-60% of the material produced based on the manufacturing processes and purification employed. (cdc.gov)
  • Nanofibrils are solid on the inside, as opposed to hollow nanotubes. (wikipedia.org)
  • The system works by remotely oscillating positive and negative charges in each nanotube, causing them to chain together into long wires. (nanowerk.com)
  • Cherukuri's specially designed Tesla coil even generates a tractor beam-like effect as nanotube wires are pulled toward the coil over long distances. (nanowerk.com)
  • Peptide nanotubes are generally very long (several micrometers) and their length is difficult to control. (sfnano.fr)
  • Using our in-lab developed software, EndogeSeq, we identified 27 of the 104 most-discriminant peptides in the serum of 24 subjects divided evenly between high and low-exposure groups. (cdc.gov)
  • Cherukuri sees this research as setting a clear path toward scalable assembly of nanotubes from the bottom up. (nanowerk.com)

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