A polymer prepared from polyvinyl acetates by replacement of the acetate groups with hydroxyl groups. It is used as a pharmaceutic aid and ophthalmic lubricant as well as in the manufacture of surface coatings artificial sponges, cosmetics, and other products.
A polyvinyl resin used extensively in the manufacture of plastics, including medical devices, tubing, and other packaging. It is also used as a rubber substitute.
'Polyvinyls' is a term that refers to a group of polymers synthesized from vinyl chloride, including polyvinyl chloride (PVC) and polyvinylidene chloride (PVDC), which are widely used in various medical applications such as manufacturing of medical devices, tubing, packaging materials, and pharmaceutical containers due to their chemical resistance, durability, and versatility.
A polyvinyl polymer of variable molecular weight; used as suspending and dispersing agent and vehicle for pharmaceuticals; also used as blood volume expander.
Materials incorporated mechanically in plastics (usually PVC) to increase flexibility, workability or distensibility; due to the non-chemical inclusion, plasticizers leach out from the plastic and are found in body fluids and the general environment.
Silicon polymers that contain alternate silicon and oxygen atoms in linear or cyclic molecular structures.
An ester of phthalic acid. It appears as a light-colored, odorless liquid and is used as a plasticizer for many resins and elastomers.
Gauze material used to absorb body fluids during surgery. Referred to as GOSSYPIBOMA if accidentally retained in the body following surgery.
A gas that has been used as an aerosol propellant and is the starting material for polyvinyl resins. Toxicity studies have shown various adverse effects, particularly the occurrence of liver neoplasms.
A method of hemostasis utilizing various agents such as Gelfoam, silastic, metal, glass, or plastic pellets, autologous clot, fat, and muscle as emboli. It has been used in the treatment of spinal cord and INTRACRANIAL ARTERIOVENOUS MALFORMATIONS, renal arteriovenous fistulas, gastrointestinal bleeding, epistaxis, hypersplenism, certain highly vascular tumors, traumatic rupture of blood vessels, and control of operative hemorrhage.
A group of compounds that has the general structure of a dicarboxylic acid-substituted benzene ring. The ortho-isomer is used in dye manufacture. (Dorland, 28th ed)
Substances used to create an impression, or negative reproduction, of the teeth and dental arches. These materials include dental plasters and cements, metallic oxide pastes, silicone base materials, or elastomeric materials.
Nonexpendable apparatus used during surgical procedures. They are differentiated from SURGICAL INSTRUMENTS, usually hand-held and used in the immediate operative field.
Sterile, gelatin-base surgical sponge applied topically as an adjunct to hemostasis when the control of bleeding by conventional procedures is ineffective to reduce capillary ooze or is impractical. (From AMA Drug Evaluations Annual, 1994, p797)
Procedure of producing an imprint or negative likeness of the teeth and/or edentulous areas. Impressions are made in plastic material which becomes hardened or set while in contact with the tissue. They are later filled with plaster of Paris or artificial stone to produce a facsimile of the oral structures present. Impressions may be made of a full complement of teeth, of areas where some teeth have been removed, or in a mouth from which all teeth have been extracted. (Illustrated Dictionary of Dentistry, 1982)
Organic mercury compounds in which the mercury is attached to a phenyl group. Often used as fungicides and seed treatment agents.
Vinyl compounds, in the context of medical materials, refer to synthetic polymers made from vinyl chloride or vinyl acetate monomers, which are used in the production of various medical devices and supplies such as blood bags, intravenous (IV) bags, tubing, and gloves due to their flexibility, transparency, and resistance to chemicals and heat.
A group of thermoplastic or thermosetting polymers containing polyisocyanate. They are used as ELASTOMERS, as coatings, as fibers and as foams.
Containers, packaging, and packaging materials for processed and raw foods and beverages. It includes packaging intended to be used for storage and also used for preparation of foods such as microwave food containers versus COOKING AND EATING UTENSILS. Packaging materials may be intended for food contact or designated non-contact, for example, shipping containers. FOOD LABELING is also available.
A tissue adhesive that is applied as a monomer to moist tissue and polymerizes to form a bond. It is slowly biodegradable and used in all kinds of surgery, including dental.
Polymeric materials (usually organic) of large molecular weight which can be shaped by flow. Plastic usually refers to the final product with fillers, plasticizers, pigments, and stabilizers included (versus the resin, the homogeneous polymeric starting material). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Containers, packaging, and packaging materials for drugs and BIOLOGICAL PRODUCTS. These include those in ampule, capsule, tablet, solution or other forms. Packaging includes immediate-containers, secondary-containers, and cartons. In the United States, such packaging is controlled under the Federal Food, Drug, and Cosmetic Act which also stipulates requirements for tamper-resistance and child-resistance. Similar laws govern use elsewhere. (From Code of Federal Regulations, 21 CFR 1 Section 210, 1993) DRUG LABELING is also available.
The process of protecting various samples of biological material.
Ethyl ester of iodinated fatty acid of poppyseed oil. It contains 37% organically bound iodine and has been used as a diagnostic aid (radiopaque medium) and as an antineoplastic agent when part of the iodine is 131-I. (From Merck Index, 11th ed)
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.
A mobile, very volatile, highly flammable liquid used as an inhalation anesthetic and as a solvent for waxes, fats, oils, perfumes, alkaloids, and gums. It is mildly irritating to skin and mucous membranes.
Salts and esters of the 18-carbon saturated, monocarboxylic acid--stearic acid.
Usually inert substances added to a prescription in order to provide suitable consistency to the dosage form. These include binders, matrix, base or diluent in pills, tablets, creams, salves, etc.
A generic term for all substances having the properties of stretching under tension, high tensile strength, retracting rapidly, and recovering their original dimensions fully. They are generally POLYMERS.
The aggregate enterprise of manufacturing and technically producing chemicals. (From Random House Unabridged Dictionary, 2d ed)
Administration of a soluble dosage form between the cheek and gingiva. It may involve direct application of a drug onto the buccal mucosa, as by painting or spraying.
A diffuse parenchymal lung disease caused by inhalation of dust and by tissue reaction to their presence. These inorganic, organic, particulate, or vaporized matters usually are inhaled by workers in their occupational environment, leading to the various forms (ASBESTOSIS; BYSSINOSIS; and others). Similar air pollution can also have deleterious effects on the general population.
Polymerized forms of styrene used as a biocompatible material, especially in dentistry. They are thermoplastic and are used as insulators, for injection molding and casting, as sheets, plates, rods, rigid forms and beads.
Relating to the size of solids.
Agents employed in the preparation of histologic or pathologic specimens for the purpose of maintaining the existing form and structure of all of the constituent elements. Great numbers of different agents are used; some are also decalcifying and hardening agents. They must quickly kill and coagulate living tissue.
The preparation, mixing, and assembling of a drug. (From Remington, The Science and Practice of Pharmacy, 19th ed, p1814)
Polymers of silicone that are formed by crosslinking and treatment with amorphous silica to increase strength. They have properties similar to vulcanized natural rubber, in that they stretch under tension, retract rapidly, and fully recover to their original dimensions upon release. They are used in the encapsulation of surgical membranes and implants.
Characteristics or attributes of the outer boundaries of objects, including molecules.
Organic compounds which contain tin in the molecule. Used widely in industry and agriculture.
Synthetic thermoplastics that are tough, flexible, inert, and resistant to chemicals and electrical current. They are often used as biocompatible materials for prostheses and implants.
Infections with unicellular organisms formerly members of the subkingdom Protozoa.
Chronic inflammation and granuloma formation around irritating foreign bodies.
Stable iodine atoms that have the same atomic number as the element iodine, but differ in atomic weight. I-127 is the only naturally occurring stable iodine isotope.
The resistance that a gaseous or liquid system offers to flow when it is subjected to shear stress. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Chemistry dealing with the composition and preparation of agents having PHARMACOLOGIC ACTIONS or diagnostic use.
A plasticizer used in most plastics and found in water, air, soil, plants and animals. It may have some adverse effects with long-term exposure.
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.
Compounds formed by the joining of smaller, usually repeating, units linked by covalent bonds. These compounds often form large macromolecules (e.g., BIOPOLYMERS; PLASTICS).
Administration of antineoplastic agents together with an embolizing vehicle. This allows slow release of the agent as well as obstruction of the blood supply to the neoplasm.
Sterile solutions that are intended for instillation into the eye. It does not include solutions for cleaning eyeglasses or CONTACT LENS SOLUTIONS.
The process of keeping pharmaceutical products in an appropriate location.
A broad family of synthetic organosiloxane polymers containing a repeating silicon-oxygen backbone with organic side groups attached via carbon-silicon bonds. Depending on their structure, they are classified as liquids, gels, and elastomers. (From Merck Index, 12th ed)
Encrustations, formed from microbes (bacteria, algae, fungi, plankton, or protozoa) embedding in extracellular polymers, that adhere to surfaces such as teeth (DENTAL DEPOSITS); PROSTHESES AND IMPLANTS; and catheters. Biofilms are prevented from forming by treating surfaces with DENTIFRICES; DISINFECTANTS; ANTI-INFECTIVE AGENTS; and antifouling agents.

Gonadotropin-releasing hormone analogue conjugates with strong selective antitumor activity. (1/496)

Conjugation of gonadotropin-releasing hormone (GnRH) analogues GnRH-III, MI-1544, and MI-1892 through lysyl side chains and a tetrapeptide spacer, Gly-Phe-Leu-Gly (X) to a copolymer, poly(N-vinylpyrrolidone-co-maleic acid) (P) caused increased antiproliferative activity toward MCF-7 and MDA-MB-231 breast, PC3 and LNCaP prostate, and Ishikawa endometrial cancer cell lines in culture and against tumor development by xenografts of the breast cancer cells in immunodeficient mice. MCF-7 cells treated with P-X-1544 and P-X-1892 displayed characteristic signs of apoptosis, including vacuoles in the cytoplasm, rounding up, apoptotic bodies, bleb formation, and DNA fragmentation. Conjugates, but not free peptides, inhibited cdc25 phosphatase and caused accumulation of Ishikawa and PC3 cells in the G2/M phase of the cell cycle after 24 h at lower doses and in the G1 and G2 phases after 48 h. Since P-X-peptides appear to be internalized, the increased cytotoxicity of the conjugates is attributed to protection of peptides from proteolysis, enhanced interaction of the peptides with the GnRH receptors, and/or internalization of P-X-peptide receptor complexes so that P can exert toxic effects inside, possibly by inhibiting enzymes involved in the cell cycle. The additional specificity of P-X-peptides compared with free peptides for direct antiproliferative effects on the cancer cells but not for interactions in the pituitary indicates the therapeutic potential of the conjugates.  (+info)

Low mortality rates in industrial cohort studies due to selection for work and survival in the industry. (2/496)

Occupational groups are often described as being relatively healthy because their mortality rates are lower than those of the national average. Although correct this confuses the issue for those who are interested in assessing the effects of exposure to a particular chemical. In a further analysis of data collected in a study of all men ever exposed to vinyl chloride monomer in the manufacture of polyvinyl chloride in Great Britain, three factors have been shown to contribute to the low mortality rates that were observed. The three factors: the selection of a healthy population for employment, the survival in the industry of the healthier men, and the length of time that this population has been pursued, have been quantified. The mortality experience within five years of entering this industry was shown to be as low as 37% of that expected; for circulatory disease and respiratory disease it was as low as 21%. There was a progressive increase in standardized mortality ratio with the length of time since entry so that the effect had almost disappeared 15 years after entry. To avoid confounding the selection effect with the survival effect the latter was measured by separating men who survived 15 years after entering the industry according to whether or not they were still in the industry after this period. Those who had left experienced an overall standardized mortality ratio some 50% higher than those still in the industry. This effect, although consistent in the age groups between 25 and 74 years and for all cause groups studied, was greatest in those aged between 25 and 44 years and for lung cancer and respiratory disease.  (+info)

Role of elevated plasma transforming growth factor-beta1 levels in wound healing. (3/496)

Transforming growth factor (TGF)-beta1 plays a central role in wound healing. Wounds treated with neutralizing antibody to TGF-beta1 have a lower inflammatory response, reduced early extracellular matrix deposition, and reduced later cutaneous scarring, indicating the importance of local tissue TGF-beta1. By contrast, increasing the local, tissue levels of TGF-beta1 increases the early extracellular matrix deposition but does not alter scar formation. Increased levels of plasma TGF-beta1 correlate with increased fibrogenesis in the lung, kidneys, and liver. The aim of the present study was to investigate the role of elevated systemic levels of TGF-beta1 on wound healing. We used transgenic mice that express high levels of active TGF-beta1 and have elevated plasma levels of TGF-beta1 and wild-type mice of the same strain as controls. Incisional wounds and subcutaneously implanted polyvinyl alcohol (PVA) sponges were analyzed. Surprisingly, cutaneous wounds in transgenic, TGF-beta1-overexpressing mice healed with reduced scarring accompanied by an increase in the immunostaining for TGF-beta3 and TGF-beta-receptor RII and a decrease in immunostaining for TGF-beta1 compared with wounds in control mice. By contrast, the PVA sponges showed the opposite response, with PVA sponges from transgenic mice demonstrating an enhanced rate of cellular influx and matrix deposition into the sponges accompanied by an increase in the immunostaining for all three TGF-beta isoforms and their receptors compared with PVA sponges from control mice. Together, the data demonstrate that increased circulating levels of TGF-beta1 do not always result in increased expression or activity in selected target tissues such as the skin. The two wound models, subcutaneously implanted PVA sponges and cutaneous incisional wounds, differ significantly in terms of host response patterns. Finally, the data reinforce our previous observations that the relative ratios of the three TGF-beta isoforms is critical for control of scarring.  (+info)

Mortality and cancer morbidity in a group of Swedish VCM and PCV production workers. (4/496)

The cohort of workers employed in a Swedish vinyl chloride/poly(vinyl chloride) plant since its start in the early 1940's has been followed for mortality and cancer morbidity patterns. Only 21 of the 771 persons could not be traced. Difficulties in establishing exposure levels at different work areas in the past makes an evaluation of dose-effect relationships impossible. A four- to fivefold excess of pancreas/liver tumors was found, including two cases later classified as angiosarcomas of the liver. The number of brain tumors and suicide do not deviate significantly from expected. Cardiovascular and cerebrovascular diseases, on the other hand, differ significantly from the expected. The discrepancies between previous reports on VCM/PVC workers and this report are discussed. The possible etiology of the cardiovascular deaths is also discussed.  (+info)

Malignant tumors of the liver and lungs in an area with a PVC industry. (5/496)

The incidence of malignant tumors of the lung and bronchus and of cytologically confirmed primary malignant tumor of the liver was analyzed for a 4-yr period in a city with several factories, including a PVC industry. Prior to the study two cases of angio-sarcoma of the liver were diagnosed in workers employed in PVC production. The total incidence of analyzed tumors was only slightly higher than predicted. The tumors of the liver recorded did not show any dependence on place of work or residence. During the period of observation, malignant tumors of the bronchus (lung) were not recorded in the PVC industry. Their rate in the area in which the PVC industry is situated was approximately the same as that for the entire city area. The study does not indicate that the occurrence of malignant tumors other than angiosarcoma is associated with exposure to vinyl chloride.  (+info)

Partial blocking of NMDA receptors reduces plastic changes induced by short-lasting classical conditioning in the SI barrel cortex of adult mice. (6/496)

The effect of blockade of N-methyl-D-aspartate (NMDA) receptors in the barrel cortex upon the learning-induced changes of the cortical body map was examined in adult mice. We have previously found that three sensory conditioning sessions, in which stimulation of a row of vibrissae was paired with a tail shock, produced an enlargement of the functional representation of a row of vibrissae stimulated during training. Implantation of the slow release polymer Elvax, containing 2-amino-5-phosphonovalerate (APV, 50 mM), in the vicinity of the barrel cortex was performed 1 day before conditioning to block NMDA receptors. The cortical representation of a trained row of vibrissae was visualized with 2-deoxyglucose (2DG) functional brain mapping 1 day after the completion of the conditioning procedure. The partial blockade of NMDA receptors within the barrel cortex reduced (by half) the expansion of the cortical representation of a trained row of vibrissae as compared to the enlargement of the cortical representation of a trained row found in untreated (60%) and Elvax-PBS implanted (47%) mice. The results provide evidence that the learning-induced processes of cortical map reorganization involve mechanisms that depend on NMDA receptor activation.  (+info)

The hazards of vinyl glove ingestion in the mentally retarded patient with pica: new implications for surgical management. (7/496)

OBJECTIVE: To report experience with the treatment of complications of vinyl glove ingestion in mentally retarded patients with pica. DESIGN: A retrospective case series. SETTING: Two university-affiliated hospitals. PATIENTS: Five mentally retarded patients, 4 with a history of pica, who were admitted for the management of complications resulting from the ingestion of vinyl gloves. MAIN OUTCOME MEASURES: Type of complication, treatment and operative outcome. FINDINGS: The patients ranged in age from 26 to 46 years. One patient died while awaiting surgical consultation of massive gastrointestinal bleeding from a large gastric ulcer caused by a vinyl glove bezoar (VGB). Four VGBs were removed surgically. Endoscopic removal was difficult or impossible because the gloves had become hardened and matted. CONCLUSIONS: VGB should be considered in institutionalized mentally retarded people with a history of pica when they present with gastrointestinal symptoms. VGBs should be removed directly by laparotomy, gastrotomy or enterotomy. Endoscopic removal is not recommended.  (+info)

Intradermal irritation of dental bleaching agents in rats. (8/496)

AIM: To evaluate the irritative potential of three dental bleaching agents (hydrogen oxide, carbopol, and carbamide peroxide). METHODS: In rats, Evans blue (2.5%, 1 mL.L-1) was injected i.v. and later each test solution was injected intradermally on the back. After the concentration of the dye in the stained skin area was determined by spectrophotometric analysis. RESULTS: All the dental bleaching agents caused increase of vascular permeability and the intensity varied with the time. CONCLUSION: Dental bleach agents had a great potential for irritating soft tissues.  (+info)

I'm sorry for any confusion, but "Polyvinyl Alcohol" is not a medical term. It is a chemical compound used in various industrial and commercial applications, including the production of adhesives, paints, and medical devices. Polyvinyl Alcohol is a type of synthetic polymer made from the polymerization of vinyl acetate monomer, followed by alcoholysis to replace the acetate groups with hydroxyl groups.

In a medical context, Polyvinyl Alcohol might be used in certain medical devices or applications, such as contact lenses, eye drops, and drug delivery systems, due to its biocompatibility and resistance to protein absorption. However, it is not a term commonly used to describe a medical condition or treatment.

I'm sorry for any confusion, but "Polyvinyl Chloride" (PVC) is not a medical term. It is a type of synthetic plastic polymer material. PVC is commonly used in various industrial, commercial, and consumer products, such as pipes, cable insulation, clothing, and inflatable items.

If you have any medical concerns or questions, please provide them, and I would be happy to help you find a relevant answer.

I'm sorry for any confusion, but "Polyvinyls" is not a medical term. It is a chemical term that refers to polymers made from vinyl chloride, which is used in the production of various plastics and resins. If you have any questions about medical terms or concepts, I'd be happy to help with those!

Povidone, also known as PVP or polyvinylpyrrolidone, is not a medication itself but rather a pharmaceutical ingredient used in various medical and healthcare products. It is a water-soluble synthetic polymer that has the ability to bind to and carry other substances, such as drugs or iodine.

In medical applications, povidone is often used as a binder or coating agent in pharmaceutical tablets and capsules. It can also be found in some topical antiseptic solutions, such as those containing iodine, where it helps to stabilize and control the release of the active ingredient.

It's important to note that while povidone is a widely used pharmaceutical ingredient, it is not typically considered a medication on its own.

Plasticizers are substances added to polymers or plastics to increase their flexibility, workability, and durability. They achieve this by reducing the intermolecular forces between polymer chains, thereby lowering the glass transition temperature (Tg) of the material. This allows the plastic to remain flexible even at lower temperatures. Common plasticizers include phthalates, adipates, and epoxy compounds. It is important to note that some plasticizers can have potential health concerns, and their use may be regulated in certain applications.

Siloxanes are a group of synthetic compounds that contain repeating units of silicon-oxygen-silicon (Si-O-Si) bonds, often combined with organic groups such as methyl or ethyl groups. They are widely used in various industrial and consumer products due to their unique properties, including thermal stability, low surface tension, and resistance to water and heat.

In medical terms, siloxanes have been studied for their potential use in medical devices and therapies. For example, some siloxane-based materials have been developed for use as coatings on medical implants, such as catheters and stents, due to their ability to reduce friction and prevent bacterial adhesion.

However, it's worth noting that exposure to high levels of certain types of siloxanes has been linked to potential health effects, including respiratory irritation and reproductive toxicity. Therefore, appropriate safety measures should be taken when handling these compounds in a medical or industrial setting.

Diethylhexyl Phthalate (DEHP) is a type of phthalate compound that is commonly used as a plasticizer, a substance added to plastics to make them more flexible and durable. DEHP is a colorless, oily liquid with an odor similar to oil or benzene. It is soluble in organic solvents but not in water.

DEHP is used primarily in the production of polyvinyl chloride (PVC) plastics, such as flexible tubing, hoses, and medical devices like blood bags and intravenous (IV) lines. DEHP can leach out of these products over time, particularly when they are subjected to heat or other stressors, leading to potential human exposure.

Exposure to DEHP has been linked to a variety of health effects, including reproductive toxicity, developmental and neurological problems, and an increased risk of cancer. As a result, the use of DEHP in certain applications has been restricted or banned in some countries. The medical community is also moving towards using alternative plasticizers that are considered safer for human health.

Surgical sponges are absorbent, sterile materials used in medical procedures to soak up bodily fluids and help maintain a clean surgical field. They are typically made from gauze material and come in various sizes and shapes to accommodate different surgical needs. Surgical sponges are carefully counted before and after a procedure to ensure that none are accidentally left inside the patient's body.

Vinyl Chloride is not a medical term, but rather a chemical compound. It's an organochloride with the formula C2H3Cl, and it's a colorless gas at room temperature that is used primarily in the production of polyvinyl chloride (PVC) plastics.

However, Vinyl Chloride is relevant to medical professionals because exposure to this compound has been linked to an increased risk of a rare form of liver cancer called hepatic angiosarcoma, as well as other health problems such as neurological damage and immune system suppression. Therefore, occupational exposure to Vinyl Chloride is regulated by organizations like the Occupational Safety and Health Administration (OSHA) in the United States.

Therapeutic embolization is a medical procedure that involves intentionally blocking or obstructing blood vessels to stop excessive bleeding or block the flow of blood to a tumor or abnormal tissue. This is typically accomplished by injecting small particles, such as microspheres or coils, into the targeted blood vessel through a catheter, which is inserted into a larger blood vessel and guided to the desired location using imaging techniques like X-ray or CT scanning. The goal of therapeutic embolization is to reduce the size of a tumor, control bleeding, or block off abnormal blood vessels that are causing problems.

Phthalic acids are organic compounds with the formula C6H4(COOH)2. They are white crystalline solids that are slightly soluble in water and more soluble in organic solvents. Phthalic acids are carboxylic acids, meaning they contain a functional group consisting of a carbon atom double-bonded to an oxygen atom and single-bonded to a hydroxyl group (-OH).

Phthalic acids are important intermediates in the chemical industry and are used to produce a wide range of products, including plastics, resins, and personal care products. They are also used as solvents and as starting materials for the synthesis of other chemicals.

Phthalic acids can be harmful if swallowed, inhaled, or absorbed through the skin. They can cause irritation to the eyes, skin, and respiratory tract, and prolonged exposure can lead to more serious health effects. Some phthalates, which are compounds that contain phthalic acid, have been linked to reproductive and developmental problems in animals and are considered to be endocrine disruptors. As a result, the use of certain phthalates has been restricted in some countries.

Dental impression materials are substances used to create a replica or negative reproduction of the oral structures, including teeth, gums, and surrounding tissues. These materials are often used in dentistry to fabricate dental restorations, orthodontic appliances, mouthguards, and various other dental devices.

There are several types of dental impression materials available, each with its unique properties and applications:

1. Alginate: This is a common and affordable material derived from algae. It is easy to mix and handle, sets quickly, and provides a detailed impression of the oral structures. However, alginate impressions are not as durable as other materials and must be poured immediately after taking the impression.
2. Irreversible Hydrocolloid: This material is similar to alginate but offers better accuracy and durability. It requires more time to mix and set, but it can be stored for a longer period before pouring the cast.
3. Polyvinyl Siloxane (PVS): Also known as silicone impression material, PVS provides excellent detail, accuracy, and dimensional stability. It is available in two types: addition-cured and condensation-cured. Addition-cured PVS offers better accuracy but requires more time to mix and set. Condensation-cured PVS sets faster but may shrink slightly over time.
4. Polyether: This material provides high accuracy, excellent detail, and good tear resistance. It is also sensitive to moisture, making it suitable for impressions where a dry field is required. However, polyether has a strong odor and taste, which some patients find unpleasant.
5. Vinyl Polysiloxane (VPS): This material is similar to PVS but offers better tear strength and flexibility. It is also less sensitive to moisture than polyether, making it suitable for various applications.
6. Zinc Oxide Eugenol: This is a traditional impression material used primarily for temporary impressions or bite registrations. It has a low cost and is easy to mix and handle but does not provide the same level of detail as other materials.

The choice of dental impression material depends on various factors, including the type of restoration, the patient's oral condition, and the clinician's preference.

Surgical equipment refers to the specialized tools and instruments used by medical professionals during surgical procedures. These devices are designed to assist in various aspects of surgery, such as cutting, grasping, retraction, clamping, and suturing. Surgical equipment can be categorized into several types based on their function and use:

1. Cutting instruments: These include scalpels, scissors, and surgical blades designed to cut through tissues with precision and minimal trauma.

2. Grasping forceps: Forceps are used to hold, manipulate, or retrieve tissue, organs, or other surgical tools. Examples include Babcock forceps, Kelly forceps, and Allis tissue forceps.

3. Retractors: These devices help to expose deeper structures by holding open body cavities or tissues during surgery. Common retractors include Weitlaner retractors, Army-Navy retractors, and self-retaining retractors like the Bookwalter system.

4. Clamps: Used for occluding blood vessels, controlling bleeding, or approximating tissue edges before suturing. Examples of clamps are hemostats, bulldog clips, and Satinsky clamps.

5. Suction devices: These tools help remove fluids, debris, and smoke from the surgical site, improving visibility for the surgeon. Examples include Yankauer suctions and Frazier tip suctions.

6. Needle holders: Specialized forceps designed to hold suture needles securely during the process of suturing or approximating tissue edges.

7. Surgical staplers: Devices that place linear staple lines in tissues, used for quick and efficient closure of surgical incisions or anastomoses (joining two structures together).

8. Cautery devices: Electrosurgical units that use heat generated by electrical current to cut tissue and coagulate bleeding vessels.

9. Implants and prosthetics: Devices used to replace or reinforce damaged body parts, such as artificial joints, heart valves, or orthopedic implants.

10. Monitoring and navigation equipment: Advanced tools that provide real-time feedback on patient physiology, surgical site anatomy, or instrument positioning during minimally invasive procedures.

These are just a few examples of the diverse range of instruments and devices used in modern surgery. The choice of tools depends on various factors, including the type of procedure, patient characteristics, and surgeon preference.

A gelatin sponge, absorbable is a surgical implant material that is derived from animal collagen. It is prepared in the form of a sterile, compressed sponge which can be expanded with the addition of fluids. The sponge is designed to absorb and hold surgical drainage, promote healing by providing a framework for the growth of new tissue, and then gradually break down and be absorbed by the body over time. It is often used in neurosurgery, plastic surgery, and other surgical specialties for its hemostatic (bleeding control) and supportive properties.

A dental impression technique is a method used in dentistry to create a detailed and accurate replica of a patient's teeth and oral structures. This is typically accomplished by using an impression material, which is inserted into a tray and then placed in the patient's mouth. The material sets or hardens, capturing every detail of the teeth, gums, and other oral tissues.

There are several types of dental impression techniques, including:

1. Irreversible Hydrocolloid Impression Material: This is a common type of impression material that is made of alginate powder mixed with water. It is poured into a tray and inserted into the patient's mouth. Once set, it is removed and used to create a cast or model of the teeth.

2. Reversible Hydrocolloid Impression Material: This type of impression material is similar to irreversible hydrocolloid, but it can be reused. It is made of agar and water and is poured into a tray and inserted into the patient's mouth. Once set, it is removed and reheated to be used again.

3. Polyvinyl Siloxane (PVS) Impression Material: This is a two-part impression material that is made of a base and a catalyst. It is poured into a tray and inserted into the patient's mouth. Once set, it is removed and used to create a cast or model of the teeth. PVS is known for its high accuracy and detail.

4. Addition Silicone Impression Material: This is another two-part impression material that is made of a base and a catalyst. It is similar to PVS, but it has a longer working time and sets slower. It is often used for full-arch impressions or when there is a need for a very detailed impression.

5. Elastomeric Impression Material: This is a type of impression material that is made of a rubber-like substance. It is poured into a tray and inserted into the patient's mouth. Once set, it is removed and used to create a cast or model of the teeth. Elastomeric impression materials are known for their high accuracy and detail.

The dental impression technique is an essential part of many dental procedures, including creating crowns, bridges, dentures, and orthodontic appliances. The accuracy and detail of the impression can significantly impact the fit and function of the final restoration or appliance.

Phenylmercury compounds are organic mercury salts that contain a phenyl group, which is a functional group consisting of a benzene ring with a hydroxyl group (-PHenyl-). These compounds were once used in various industrial and medical applications, such as antiseptics, preservatives, and vaccines. However, due to their toxicity and potential for bioaccumulation, the use of phenylmercury compounds has been largely discontinued.

Exposure to phenylmercury compounds can cause a range of adverse health effects, including neurological damage, kidney dysfunction, and developmental problems in children. Therefore, it is important to minimize exposure to these compounds and handle them with care if they are still used in certain applications.

"Vinyl compounds" is not a term used in medical definitions. It is a term used in chemistry and materials science to refer to a group of chemicals that contain carbon-based molecules with a vinyl group, which is a functional group consisting of a double bond between two carbon atoms, with one of the carbons also being bonded to a hydrogen atom (-CH2=CH-).

Vinyl compounds are used in various industrial and consumer products, including plastics, resins, adhesives, and coatings. Some vinyl compounds, such as polyvinyl chloride (PVC), have been used in medical devices and supplies, such as intravenous (IV) bags, tubing, and blood vessel catheters. However, the use of PVC and other vinyl compounds in medical applications has raised concerns about potential health risks due to the release of toxic chemicals, such as phthalates and dioxins, during manufacturing, use, and disposal. Therefore, alternative materials are being developed and used in medical devices and supplies.

I'm sorry for any confusion, but "Polyurethanes" are not a medical term. They are a type of polymer that is used in a variety of industrial and consumer products, including foam cushions, insulation, and packaging materials. Polyurethanes are created through a chemical reaction between diisocyanates and polyols. While they have many applications in the medical field, such as in the production of medical devices and equipment, they are not a medical term themselves.

I'm sorry for any confusion, but "Food Packaging" is not a medical term. It is a term used to describe the process and materials used to package food products to protect them from contamination, damage, and to provide information about the product. Medical definitions are typically related to diseases, conditions, treatments, or anatomical terms. If you have any questions related to medical terminology, I'd be happy to help with those!

I apologize for any confusion, but "Enbucrilate" is not a medical term or a medication that I am aware of. It's possible that there might be some misunderstanding or misspelling in the term. If you have more context or information about where this term came from, I may be able to provide a more accurate and helpful response.

However, if you are referring to "bucrilate" which is a type of polymer used in some medical applications such as wound dressings, then it is a substance that can absorb large amounts of water and create a gel-like barrier between the wound and the outside environment, helping to keep the wound moist and promote healing.

If you have any further questions or concerns, please don't hesitate to ask.

"Plastics" is not a term that has a specific medical definition. However, in a broader context, plastics can refer to a wide range of synthetic or semi-synthetic materials that are used in various medical applications due to their durability, flexibility, and ability to be molded into different shapes. Some examples include:

1. Medical devices such as catheters, implants, and surgical instruments.
2. Packaging for medical supplies and pharmaceuticals.
3. Protective barriers like gloves and gowns used in medical settings.
4. Intraocular lenses and other ophthalmic applications.

It's important to note that the term "plastics" is not a medical term per se, but rather a general category of materials with diverse uses across different industries, including healthcare.

Drug packaging refers to the process and materials used to enclose, protect, and provide information about a pharmaceutical product. The package may include the container for the medication, such as a bottle or blister pack, as well as any accompanying leaflets or inserts that contain details about the drug's dosage, side effects, and proper use.

The packaging of drugs serves several important functions:

1. Protection: Proper packaging helps to protect the medication from physical damage, contamination, and degradation due to exposure to light, moisture, or air.
2. Child-resistance: Many drug packages are designed to be child-resistant, meaning they are difficult for young children to open but can still be easily accessed by adults.
3. Tamper-evidence: Packaging may also include features that make it easy to detect if the package has been tampered with or opened without authorization.
4. Labeling: Drug packaging must comply with regulatory requirements for labeling, including providing clear and accurate information about the drug's ingredients, dosage, warnings, and precautions.
5. Unit-dose packaging: Some drugs are packaged in unit-dose form, which means that each dose is individually wrapped or sealed in a separate package. This can help to reduce medication errors and ensure that patients receive the correct dosage.
6. Branding and marketing: Drug packaging may also serve as a tool for branding and marketing the product, with distinctive colors, shapes, and graphics that help to differentiate it from similar products.

Biological preservation is the process of preventing decomposition or decay of biological materials, such as tissues, cells, organs, or organisms, in order to maintain their structural and functional integrity for further studies, research, education, or conservation purposes. This can be achieved through various methods, including fixation, freezing, drying, or the use of chemical preservatives. The goal is to maintain the samples in a stable state so that they can be examined, analyzed, or used in experiments at a later time.

Ethiodized oil is a type of poppy seed oil that has been chemically treated with iodine. It is a highly dense form of iodine, which is used as a radiocontrast medium for imaging studies, such as X-rays and CT scans. The iodine in the ethiodized oil absorbs the X-rays and makes certain structures in the body more visible on the images. It is typically used to help diagnose conditions related to the gastrointestinal tract, such as ulcers or tumors.

It's important to note that the use of ethiodized oil as a radiocontrast medium has declined in recent years due to the development of newer, safer contrast agents. Additionally, there are potential risks associated with its use, including allergic reactions and kidney damage, so it is typically used only when other options are not available or have been determined to be inappropriate.

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.

In medical terms, "ether" is an outdated term that was used to refer to a group of compounds known as diethyl ethers. The most common member of this group, and the one most frequently referred to as "ether," is diethyl ether, also known as sulfuric ether or simply ether.

Diethyl ether is a highly volatile, flammable liquid that was once widely used as an anesthetic agent in surgical procedures. It has a characteristic odor and produces a state of unconsciousness when inhaled, allowing patients to undergo surgery without experiencing pain. However, due to its numerous side effects, such as nausea, vomiting, and respiratory depression, as well as the risk of explosion or fire during use, it has largely been replaced by safer and more effective anesthetic agents.

It's worth noting that "ether" also has other meanings in different contexts, including a term used to describe a substance that produces a feeling of detachment from reality or a sense of unreality, as well as a class of organic compounds characterized by the presence of an ether group (-O-, a functional group consisting of an oxygen atom bonded to two alkyl or aryl groups).

Stearates are salts or esters of stearic acid, a saturated fatty acid with 18 carbons. In a medical context, stearates are often used as excipients in pharmaceutical and nutritional supplement formulations. They act as lubricants, helping to improve the flow properties of powders and facilitating the manufacturing process. Common examples include magnesium stearate and calcium stearate. However, it is important to note that there has been some controversy regarding the use of stearates in nutritional supplements, with concerns that they may reduce the bioavailability of certain active ingredients.

Excipients are inactive substances that serve as vehicles or mediums for the active ingredients in medications. They make up the bulk of a pharmaceutical formulation and help to stabilize, preserve, and enhance the delivery of the active drug compound. Common examples of excipients include binders, fillers, coatings, disintegrants, flavors, sweeteners, and colors. While excipients are generally considered safe and inert, they can sometimes cause allergic reactions or other adverse effects in certain individuals.

Elastomers are a type of polymeric material that exhibit elastic behavior when subjected to deforming forces. They have the ability to return to their original shape and size after being stretched or compressed, making them ideal for use in applications where flexibility, resilience, and durability are required.

Elastomers are composed of long chains of repeating molecular units called monomers, which are cross-linked together to form a three-dimensional network. This cross-linking gives elastomers their unique properties, such as high elasticity, low compression set, and resistance to heat, chemicals, and weathering.

Some common examples of elastomers include natural rubber, silicone rubber, neoprene, nitrile rubber, and polyurethane. These materials are used in a wide range of applications, from automotive parts and medical devices to footwear and clothing.

The chemical industry is a broad term that refers to the companies and organizations involved in the production or transformation of raw materials or intermediates into various chemical products. These products can be used for a wide range of applications, including manufacturing, agriculture, pharmaceuticals, and consumer goods. The chemical industry includes businesses that produce basic chemicals, such as petrochemicals, agrochemicals, polymers, and industrial gases, as well as those that manufacture specialty chemicals, such as dyestuffs, flavors, fragrances, and advanced materials. Additionally, the chemical industry encompasses companies that provide services related to the research, development, testing, and distribution of chemical products.

Buccal administration refers to the route of delivering a medication or drug through the buccal mucosa, which is the lining of the inner cheek in the mouth. This route allows for the medication to be absorbed directly into the bloodstream, bypassing the gastrointestinal tract and liver metabolism, which can result in faster onset of action and potentially higher bioavailability.

Buccal administration can be achieved through various forms of dosage forms such as lozenges, tablets, films, or sprays that are placed in contact with the buccal mucosa for a certain period of time until they dissolve or disintegrate and release the active ingredient. This route is commonly used for medications that require a rapid onset of action, have poor oral bioavailability, or are irritating to the gastrointestinal tract.

It's important to note that buccal administration may not be appropriate for all medications, as some drugs may be inactivated by saliva or may cause local irritation or discomfort. Therefore, it's essential to consult with a healthcare professional before using any medication through this route.

Pneumoconiosis is a group of lung diseases caused by inhaling dust particles, leading to fibrosis or scarring of the lungs. The type of pneumoconiosis depends on the specific dust inhaled. Examples include coal worker's pneumoconiosis (from coal dust), silicosis (from crystalline silica dust), and asbestosis (from asbestos fibers). These diseases are generally preventable by minimizing exposure to harmful dusts through proper engineering controls, protective equipment, and workplace safety regulations.

I'm sorry for any confusion, but "Polystyrenes" is not a medical term. Polystyrene is a type of synthetic aromatic hydrocarbon polymer that is used in a variety of commercial and industrial products, such as packaging materials, insulation, and disposable cutlery. It's important to note that some polystyrene products may contain potentially harmful chemicals, such as styrene, which can leach out into food or drink, posing potential health risks. However, the medical community primarily deals with the health effects of exposure to these chemicals rather than defining the material itself.

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.

Fixatives are substances used in histology and pathology to preserve tissue specimens for microscopic examination. They work by stabilizing the structural components of cells and tissues, preventing decomposition and autolysis. This helps to maintain the original structure and composition of the specimen as closely as possible, allowing for accurate diagnosis and research. Commonly used fixatives include formalin, glutaraldehyde, methanol, and ethanol. The choice of fixative depends on the specific type of tissue being preserved and the intended use of the specimen.

Drug compounding is the process of combining, mixing, or altering ingredients to create a customized medication to meet the specific needs of an individual patient. This can be done for a variety of reasons, such as when a patient has an allergy to a certain ingredient in a mass-produced medication, or when a patient requires a different dosage or formulation than what is available commercially.

Compounding requires specialized training and equipment, and compounding pharmacists must follow strict guidelines to ensure the safety and efficacy of the medications they produce. Compounded medications are not approved by the U.S. Food and Drug Administration (FDA), but the FDA does regulate the ingredients used in compounding and has oversight over the practices of compounding pharmacies.

It's important to note that while compounding can provide benefits for some patients, it also carries risks, such as the potential for contamination or incorrect dosing. Patients should only receive compounded medications from reputable pharmacies that follow proper compounding standards and procedures.

Silicone elastomers are a type of synthetic rubber made from silicone, which is a polymer composed primarily of silicon-oxygen bonds. They are known for their durability, flexibility, and resistance to heat, cold, and moisture. Silicone elastomers can be manufactured in various forms, including liquids, gels, and solids, and they are used in a wide range of medical applications such as:

1. Breast implants: Silicone elastomer shells filled with silicone gel are commonly used for breast augmentation and reconstruction.
2. Contact lenses: Some contact lenses are made from silicone elastomers due to their high oxygen permeability, which allows for better eye health.
3. Catheters: Silicone elastomer catheters are flexible and resistant to kinking, making them suitable for long-term use in various medical procedures.
4. Implantable drug delivery systems: Silicone elastomers can be used as a matrix for controlled release of drugs, allowing for sustained and targeted medication administration.
5. Medical adhesives: Silicone elastomer adhesives are biocompatible and can be used to attach medical devices to the skin or other tissues.
6. Sealants and coatings: Silicone elastomers can be used as sealants and coatings in medical devices to prevent leakage, improve durability, and reduce infection risk.

It is important to note that while silicone elastomers are generally considered safe for medical use, there have been concerns about the potential health risks associated with breast implants, such as capsular contracture, breast pain, and immune system reactions. However, these risks vary depending on the individual's health status and the specific type of silicone elastomer used.

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.

Organotin compounds are a group of chemical compounds that contain carbon, hydrogen, and tin. They have the general formula RnSnX4-n, where R represents an organic group (such as a methyl or phenyl group), X represents a halogen or other substituent, and n can range from 1 to 3. These compounds are used in a variety of applications, including as biocides, PVC stabilizers, and catalysts. However, they have also been found to have toxic effects on the immune system, endocrine system, and nervous system, and some organotin compounds have been restricted or banned for use in certain products due to these concerns.

I believe there may be some confusion in your question as Polyethylenes are not a medical term, but rather a category of synthetic polymers commonly used in various industrial and medical applications. Here's a brief overview:

Polyethylene (PE) is a type of thermoplastic polymer made from the monomer ethylene. It is a versatile material with numerous applications due to its chemical resistance, durability, and flexibility. There are several types of polyethylenes, including:

1. Low-density polyethylene (LDPE): This type has a lower density and more branching in its molecular structure, which results in less crystallinity. LDPE is known for its flexibility and is often used in packaging films, bags, and containers.
2. High-density polyethylene (HDPE): HDPE has a higher density and less branching, resulting in greater crystallinity. It is more rigid than LDPE and is commonly used in applications such as bottles, pipes, and containers.
3. Linear low-density polyethylene (LLDPE): This type combines the flexibility of LDPE with some of the strength and rigidity of HDPE. LLDPE has fewer branches than LDPE but more than HDPE. It is often used in film applications, such as stretch wrap and agricultural films.
4. Ultra-high molecular weight polyethylene (UHMWPE): UHMWPE has an extremely high molecular weight, resulting in exceptional wear resistance, impact strength, and chemical resistance. It is commonly used in medical applications, such as orthopedic implants and joint replacements, due to its biocompatibility and low friction coefficient.

While polyethylenes are not a medical term per se, they do have significant medical applications, particularly UHMWPE in orthopedic devices.

Protozoan infections are diseases caused by microscopic, single-celled organisms known as protozoa. These parasites can enter the human body through contaminated food, water, or contact with an infected person or animal. Once inside the body, they can multiply and cause a range of symptoms depending on the type of protozoan and where it infects in the body. Some common protozoan infections include malaria, giardiasis, amoebiasis, and toxoplasmosis. Symptoms can vary widely but may include diarrhea, abdominal pain, fever, fatigue, and skin rashes. Treatment typically involves the use of antiprotozoal medications to kill the parasites and alleviate symptoms.

A foreign-body reaction is an immune response that occurs when a non-native substance, or "foreign body," is introduced into the human body. This can include things like splinters, surgical implants, or even injected medications. The immune system recognizes these substances as foreign and mounts a response to try to eliminate them.

The initial response to a foreign body is often an acute inflammatory reaction, characterized by the release of chemical mediators that cause vasodilation, increased blood flow, and the migration of white blood cells to the site. This can result in symptoms such as redness, swelling, warmth, and pain.

If the foreign body is not eliminated, a chronic inflammatory response may develop, which can lead to the formation of granulation tissue, fibrosis, and encapsulation of the foreign body. In some cases, this reaction can cause significant tissue damage or impede proper healing.

It's worth noting that not all foreign bodies necessarily elicit a strong immune response. The nature and size of the foreign body, as well as its location in the body, can all influence the severity of the reaction.

Iodine isotopes are different forms of the chemical element iodine, which have different numbers of neutrons in their nuclei. Iodine has a total of 53 protons in its nucleus, and its stable isotope, iodine-127, has 74 neutrons, giving it a mass number of 127. However, there are also radioactive isotopes of iodine, which have different numbers of neutrons and are therefore unstable.

Radioactive isotopes of iodine emit radiation as they decay towards a stable state. For example, iodine-131 is a commonly used isotope in medical imaging and therapy, with a half-life of about 8 days. It decays by emitting beta particles and gamma rays, making it useful for treating thyroid cancer and other conditions that involve overactive thyroid glands.

Other radioactive iodine isotopes include iodine-123, which has a half-life of about 13 hours and is used in medical imaging, and iodine-125, which has a half-life of about 60 days and is used in brachytherapy (a type of radiation therapy that involves placing radioactive sources directly into or near tumors).

It's important to note that exposure to radioactive iodine isotopes can be harmful, especially if it occurs through inhalation or ingestion. This is because the iodine can accumulate in the thyroid gland and cause damage over time. Therefore, appropriate safety measures must be taken when handling or working with radioactive iodine isotopes.

Viscosity is a physical property of a fluid that describes its resistance to flow. In medical terms, viscosity is often discussed in relation to bodily fluids such as blood or synovial fluid (found in joints). The unit of measurement for viscosity is the poise, although it is more commonly expressed in millipascals-second (mPa.s) in SI units. Highly viscous fluids flow more slowly than less viscous fluids. Changes in the viscosity of bodily fluids can have significant implications for health and disease; for example, increased blood viscosity has been associated with cardiovascular diseases, while decreased synovial fluid viscosity can contribute to joint pain and inflammation in conditions like osteoarthritis.

Pharmaceutical chemistry is a branch of chemistry that deals with the design, synthesis, and development of chemical entities used as medications. It involves the study of drugs' physical, chemical, and biological properties, as well as their interactions with living organisms. This field also encompasses understanding the absorption, distribution, metabolism, and excretion (ADME) of drugs in the body, which are critical factors in drug design and development. Pharmaceutical chemists often work closely with biologists, medical professionals, and engineers to develop new medications and improve existing ones.

Dibutyl phthalate (DBP) is a synthetic chemical compound that belongs to a class of chemicals called phthalates. It is a colorless, oily liquid with a mild odor and is widely used as a plasticizer to make plastics more flexible and durable. DBP is commonly added to polyvinyl chloride (PVC) products such as vinyl flooring, wall coverings, shower curtains, and consumer products like cosmetics, personal care products, and cleaning solutions.

In medical terms, DBP has been identified as a reproductive toxicant and endocrine disruptor, which means it can interfere with the body's hormonal system and potentially affect reproductive health. Studies have shown that exposure to DBP during pregnancy may be associated with adverse outcomes such as reduced fetal growth, abnormalities in male reproductive development, and behavioral problems in children.

Therefore, it is important to limit exposure to DBP and other phthalates, especially for pregnant women and young children. Some steps you can take to reduce your exposure include avoiding plastic containers with the recycling codes 3 or 7 (which may contain phthalates), choosing personal care products that are labeled "phthalate-free," and using natural cleaning products whenever possible.

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.

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).

Chemoembolization, therapeutic is a medical procedure that involves the delivery of chemotherapy drugs directly to a tumor through its blood supply, followed by the blocking of the blood vessel leading to the tumor. This approach allows for a higher concentration of the chemotherapy drug to be delivered directly to the tumor while minimizing exposure to the rest of the body. The embolization component of the procedure involves blocking the blood vessel with various substances such as microspheres, gel foam, or coils, which can help to starve the tumor of oxygen and nutrients.

Therapeutic chemoembolization is typically used in the treatment of liver cancer, including primary liver cancer (hepatocellular carcinoma) and metastatic liver cancer. It may also be used in other types of cancer that have spread to the liver. The procedure can help to reduce the size of the tumor, relieve symptoms, and improve survival rates in some patients. However, like all medical procedures, it carries a risk of complications such as infection, bleeding, and damage to surrounding tissues.

Ophthalmic solutions are sterile, single-use or multi-dose preparations in a liquid form that are intended for topical administration to the eye. These solutions can contain various types of medications, such as antibiotics, anti-inflammatory agents, antihistamines, or lubricants, which are used to treat or prevent ocular diseases and conditions.

The pH and osmolarity of ophthalmic solutions are carefully controlled to match the physiological environment of the eye and minimize any potential discomfort or irritation. The solutions may be packaged in various forms, including drops, sprays, or irrigations, depending on the intended use and administration route.

It is important to follow the instructions for use provided by a healthcare professional when administering ophthalmic solutions, as improper use can lead to eye injury or reduced effectiveness of the medication.

"Drug storage" refers to the proper handling, maintenance, and preservation of medications in a safe and suitable environment to ensure their effectiveness and safety until they are used. Proper drug storage includes:

1. Protecting drugs from light, heat, and moisture: Exposure to these elements can degrade the quality and potency of medications. Therefore, it is recommended to store most drugs in a cool, dry place, away from direct sunlight.

2. Keeping drugs out of reach of children and pets: Medications should be stored in a secure location, such as a locked cabinet or medicine chest, to prevent accidental ingestion or harm to young children and animals.

3. Following storage instructions on drug labels and packaging: Some medications require specific storage conditions, such as refrigeration or protection from freezing. Always follow the storage instructions provided by the manufacturer or pharmacist.

4. Regularly inspecting drugs for signs of degradation or expiration: Check medications for changes in color, consistency, or odor, and discard any that have expired or show signs of spoilage.

5. Storing drugs separately from one another: Keep different medications separate to prevent cross-contamination, incorrect dosing, or accidental mixing of incompatible substances.

6. Avoiding storage in areas with high humidity or temperature fluctuations: Bathrooms, kitchens, and garages are generally not ideal for storing medications due to their exposure to moisture, heat, and temperature changes.

Proper drug storage is crucial for maintaining the safety, efficacy, and stability of medications. Improper storage can lead to reduced potency, increased risk of adverse effects, or even life-threatening situations. Always consult a healthcare professional or pharmacist for specific storage instructions and recommendations.

Silicones are not a medical term, but they are commonly used in the medical field, particularly in medical devices and healthcare products. Silicones are synthetic polymers made up of repeating units of siloxane, which is a chain of alternating silicon and oxygen atoms. They can exist in various forms such as oils, gels, rubbers, and resins.

In the medical context, silicones are often used for their unique properties, including:

1. Biocompatibility - Silicones have a low risk of causing an adverse reaction when they come into contact with living tissue.
2. Inertness - They do not react chemically with other substances, making them suitable for use in medical devices that need to remain stable over time.
3. Temperature resistance - Silicones can maintain their flexibility and elasticity even under extreme temperature conditions.
4. Gas permeability - Some silicone materials allow gases like oxygen and water vapor to pass through, which is useful in applications where maintaining a moist environment is essential.
5. Durability - Silicones have excellent resistance to aging, weathering, and environmental factors, ensuring long-lasting performance.

Examples of medical applications for silicones include:

1. Breast implants
2. Contact lenses
3. Catheters
4. Artificial joints and tendons
5. Bandages and wound dressings
6. Drug delivery systems
7. Medical adhesives
8. Infant care products (nipples, pacifiers)

Biofilms are defined as complex communities of microorganisms, such as bacteria and fungi, that adhere to surfaces and are enclosed in a matrix made up of extracellular polymeric substances (EPS). The EPS matrix is composed of polysaccharides, proteins, DNA, and other molecules that provide structural support and protection to the microorganisms within.

Biofilms can form on both living and non-living surfaces, including medical devices, implants, and biological tissues. They are resistant to antibiotics, disinfectants, and host immune responses, making them difficult to eradicate and a significant cause of persistent infections. Biofilms have been implicated in a wide range of medical conditions, including chronic wounds, urinary tract infections, middle ear infections, and device-related infections.

The formation of biofilms typically involves several stages, including initial attachment, microcolony formation, maturation, and dispersion. Understanding the mechanisms underlying biofilm formation and development is crucial for developing effective strategies to prevent and treat biofilm-associated infections.

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