Povidone-Iodine
Povidone
Anti-Infective Agents, Local
Chlorhexidine
Lymphocele
Instillation, Drug
2-Propanol
Chyle
Iodophors
Disinfectants
Sodium Hypochlorite
Disinfection
Skin
Encyclopedias as Topic
Hexachlorophene
Purification and characterization of rat hippocampal CA3-dendritic spines associated with mossy fiber terminals. (1/451)
We report a revised and improved isolation procedure for CA3-dendritic spines, most of them still in association with mossy fiber terminals resulting in a 7.5-fold enrichment over nuclei and a 29-fold enrichment over myelin. Additionally, red blood cells, medullated fibers, mitochondria and small synaptosomes were significantly depleted. We show by high resolution electron microscopy that this subcellular fraction contains numerous dendritic spines with a rich ultrastructure, e.g. an intact spine apparatus, membranous organelles, free and membrane-bound polyribosomes, endocytic structures and mitochondria. This improved experimental system will allow us to study aspects of post-synaptic functions at the biochemical and molecular level. (+info)A quantitative study of pinocytosis and lysosome function in experimentally induced lysosomal storage. (2/451)
The highly pinocytic epithelial cells of the visceral yolk sac from 17.5-day rat conceptuses were used as a model in which to induce engorgement of the vacuolar system by direct accumulation of substances that are not hydrolysed by lysosomal enzymes. The ultra-structural appearances of these cells in pregnant animals that 24-48h before had received intraperitoneal injections of Triton WR-1339, polyvinylpyrrolidone, dextran or sucrose revealed gross abnormalities that were confined to the vacuolar system; in comparison with normal tissue the number, and in some cases the size, of vacuoles was increased, leading to close packing within the apical cytoplasm and distortion of the normal rounded shape. By culturing yolk sacs in vitro, rates of ingestion of 125I-labelled polyvinylpyrrolidone and of 125I-labelled bovine serum albumin were determined, together with the rate of digestion of the labelled protein. The rates of exocytosis of 125I-labelled polyvinylpyrrolidone and of lysosomal enzymes were also determined. No significant differences between normal and highly vacuolated tissues were found. Apparently marked vacuolation of these cells by these agents is without significant effect on pinocytosis, exocytosis or intralysosomal proteolysis. (+info)Immature germ cell separation using a modified discontinuous Percoll gradient technique in human semen. (3/451)
The difficulty of identifying immature germ cells in unstained, fresh semen has led most laboratories to use the broad definition 'round cells' to indicate cells other than spermatozoa, thus grouping together both leukocytes and immature germ cells. This is also the case in research andrology, where very little attention has been given to immature germ cells in the semen apart from some rare exceptions, such as the attempts to study meiosis. Here we report on the use of a discontinuous Percoll gradient method modified to enable the best separation possible of immature germ cells from the other cells found in the ejaculate, in order to obtain a cellular suspension free of spermatozoa. Our technique (intra-assay variation in duplicates < 10%) demonstrated a high immature germ cell concentration in gradient fractions with 30% to 45% Percoll with a small contamination (1.5-6%) of leukocytes, confirmed by May-Grunwald-Giemsa staining, immunofluorescence and cytofluorimetry. The concentrations of immature germ cells ranged from zero in obstructive azoospermia to 2.0 x 10(6)/ml in oligozoospermia and genital tract infection. The purified immature germ cell suspensions obtained can be useful for diagnostic and research purposes. (+info)Comparative evaluation of two density gradient preparations for sperm separation for medically assisted conception. (4/451)
To evaluate and optimize the sperm separation efficiency of a novel silane-coated silica bead (Puresperm), serial studies were carried out to compare the various sperm parameters between: (i) three-layer (90%-70%-40%) Puresperm and three-layer (90%-70%-40%) conventional polyvinylpyrrolidone (PVP)-coated silica bead (Percoll) gradients; (ii) three-layer (90%-70%-40%) and two-layer (90%-45%) Puresperm gradients and separately the same for Percoll; and (iii) large (3.0 ml) and small (0.75 ml) semen loading volumes on three-layer Puresperm gradients. Normozoospermic semen samples were treated and analysed in 12 replicates for each experiment. Manual evaluation of concentration, percentage motility, percentage vitality, percentage normal morphology; computer-assisted semen analysis evaluation of concentration, percentage motility, grade of motility, motion characteristics (curvilinear velocity, linearity, amplitude of lateral head velocity, beat cross frequency, percentage hyperactivation); and yields from the initial semen samples were compared. Percoll was found to be superior to Puresperm in concentration, percentage motility, percentage vitality and yields after three-layer density gradient centrifugation. There were no significant differences in sperm parameters between two- and three-layer Percoll gradients, but three-layer Puresperm gradients behaved significantly better than two-layer gradients. Large semen volume loads on three-layer Puresperm gradients resulted in greater sperm concentrations, percentage motility, percentage vitality and percentage normal morphology, but small semen volume loads produced greater yields of good-quality spermatozoa. In the light of Percoll being withdrawn from the shelf for the use of assisted reproduction because of the presence of PVP, three-layer Puresperm gradients with large semen loading volumes appear to be an attractive alternative for sperm separation in medically assisted conception. (+info)Demonstration of thymus-independent immune system in Xenopus laevis. Response to polyvinylpyrrolidone. (5/451)
Larvae of Xenopus laevis were thymectomized at stage 45 (4 days old), and raised beyond metamorphosis. Thymectomized toads, when injected with polyvinylpyrrolidone (PVP), produced the same titres of antibodies as non-thymectomized animals, providing strong evidence that the thymus-independent immune response is present in this anuran. Antibodies were of exclusively high molecular weight, heat-stable, and 2-mercaptoethanol sensitive. After immunization, lymphoid accumulations were evident in the splenic white pulp of both thymectomized and non-thymectomized toads, but in the red pulp the accumulations were prominent only in non-thymectomized toads. (+info)Pre-freezing sperm preparation does not impair thawed spermatozoa binding to the zona pellucida. (6/451)
The present study was conducted to assess the fertilizing potential of frozen-thawed spermatozoa, which were cryopreserved after separation on a Percoll gradient, or washed out of seminal plasma. For this purpose, binding to the zona pellucida and other characteristics of the treated sperm cells were compared with those of cryopreserved spermatozoa from the same original sample which were not manipulated before freezing. Semen specimens were obtained from 80 candidates for sperm donation. Percoll-treated sperm samples compared with the sibling, unprocessed controls had significantly higher values of sperm motility characteristics and per cent of cells with normal morphology after freezing and thawing. Sperm binding ability to the zona pellucida was not statistically different (109 +/- 8.1% and 94 +/- 6.7% in unprocessed and Percoll-treated samples respectively). Sperm specimens processed by washing had significantly higher values for motility characteristics than untreated sibling samples, but no differences were found between the treated and untreated samples for morphology and binding to the zona pellucida (hemizona index of 75 +/- 7.0% and 76 +/- 6.7% in unprocessed and washed samples respectively). These findings suggest that, judged by the binding assay, the aforementioned pre-freezing separation processes have no adverse effect upon the fertilizing potential of the thawed sperm cells. These procedures make it possible to optimize the progressive motile sperm cell concentration of the frozen specimen, which facilitates the storage of samples with good quality, even when the features of the original semen are sub-optimal. (+info)Effects of Percoll separation, cryoprotective agents, and temperature on plasma membrane permeability characteristics of murine spermatozoa and their relevance to cryopreservation. (7/451)
Cryopreservation of murine spermatozoa would provide an efficient method for preserving important genotypes. However, to date such methods have resulted in low survivals with significant variability. To address this issue, a series of five experiments was performed to determine the cryobiological characteristics of murine spermatozoa. Experiments 1 and 2 investigated the effect of Percoll separation on the hydraulic conductivity (L(p)) of murine spermatozoa. Both Percoll separation and cryoprotective agents (CPAs) decreased the L(p). However, these effects were not additive. Experiment 3 was performed to determine the effect of temperature on L(p) in the presence of cryoprotectants (L(p)(CPA)), cryoprotectant permeability (P(CPA)), and the reflection coefficient (sigma) in spermatozoa from both ICR and B6C3F1 mice. Permeability parameters decreased as temperature decreased, and permeability characteristics differed between strains. In experiments 4 and 5, theoretical simulations for CPA addition and removal were developed and empirically tested. Strain-specific methods for CPA addition and removal based upon the fundamental cryobiological characteristics of murine spermatozoa resulted in higher survivals than current methods or procedures, which were used as controls. (+info)Molecular diagnostics on microfabricated electrophoretic devices: from slab gel- to capillary- to microchip-based assays for T- and B-cell lymphoproliferative disorders. (8/451)
BACKGROUND: Current methods for molecular-based diagnosis of disease rely heavily on modern molecular biology techniques for interrogating the genome for aberrant DNA sequences. These techniques typically include amplification of the target DNA sequences followed by separation of the amplified fragments by slab gel electrophoresis. As a result of the labor-intensive, time-consuming nature of slab gel electrophoresis, alternative electrophoretic formats have been developed in the form of capillary electrophoresis and, more recently, multichannel microchip electrophoresis. METHODS: Capillary electrophoresis was explored as an alternative to slab gel electrophoresis for the analysis of PCR-amplified products indicative of T- and B-cell malignancies as a means of defining the elements for silica microchip-based diagnosis. Capillary-based separations were replicated on electrophoretic microchips. RESULTS: The microchip-based electrophoretic separation effectively resolved PCR-amplified fragments from the variable region of the T-cell receptor-gamma gene (150-250 bp range) and the immunoglobulin heavy chain gene (80-140 bp range), yielding diagnostically relevant information regarding the presence of clonal DNA populations. Although hydroxyethylcellulose provided adequate separation power, the need for a coated microchannel for effective resolution necessitated additional preparative steps. In addition, preliminary data are shown indicating that polyvinylpyrrolidone may provide an adequate matrix without the need for microchannel coating. CONCLUSIONS: Separation of B- and T-cell gene rearrangement PCR products on microchips provides diagnostic information in dramatically reduced time (160 s vs 2.5 h) with no loss of diagnostic capacity when compared with current methodologies. As illustrated, this technology and methodology holds great potential for extrapolation to the abundance of similar molecular biology-based techniques. (+info)Povidone-Iodine is a broad-spectrum antimicrobial agent, which is a complex of iodine with polyvinylpyrrolidone (PVP). This complex allows for sustained release of iodine, providing persistent antimicrobial activity. It has been widely used in various clinical settings, including as a surgical scrub, wound disinfection, and skin preparation before invasive procedures. Povidone-Iodine is effective against bacteria, viruses, fungi, and spores. The mechanism of action involves the release of iodine ions, which oxidize cellular components and disrupt microbial membranes, leading to cell death.
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.
Anti-infective agents, local, are medications that are applied directly to a specific area of the body to prevent or treat infections caused by bacteria, fungi, viruses, or parasites. These agents include topical antibiotics, antifungals, antivirals, and anti-parasitic drugs. They work by killing or inhibiting the growth of the infectious organisms, thereby preventing their spread and reducing the risk of infection. Local anti-infective agents are often used to treat skin infections, eye infections, and other localized infections, and can be administered as creams, ointments, gels, solutions, or drops.
Chlorhexidine is an antimicrobial agent used for its broad-spectrum germicidal properties. It is effective against bacteria, viruses, and fungi. It is commonly used as a surgical scrub, hand sanitizer, and healthcare disinfectant. Chlorhexidine is available in various forms, including solutions, gels, and sprays. It works by disrupting the microbial cell membrane, leading to the death of the organism. It is also used in mouthwashes and skin cleansers for its antimicrobial effects.
A lymphocele is a localized collection or sac filled with lymph fluid, which usually forms as a result of surgical dissection or injury to the lymphatic vessels. The accumulation of lymph fluid occurs due to the disruption of normal lymphatic drainage in the affected area.
Lymphoceles are most commonly found following surgeries involving the lymph nodes, such as pelvic, groin, or abdominal procedures. They can also occur after radiotherapy treatments that damage the lymphatic vessels. In some cases, lymphoceles may develop spontaneously due to underlying medical conditions affecting the lymphatic system.
While lymphoceles are generally not harmful on their own, they can cause complications such as infection, delayed wound healing, or impaired limb function if they become large enough to put pressure on surrounding tissues and organs. Treatment options for lymphoceles include compression garments, percutaneous drainage, sclerosis (the injection of a substance that causes the sac to stick together), or surgical removal in severe cases.
Instillation, in the context of drug administration, refers to the process of introducing a medication or therapeutic agent into a body cavity or onto a mucous membrane surface using gentle, steady pressure. This is typically done with the help of a device such as an eyedropper, pipette, or catheter. The goal is to ensure that the drug is distributed evenly over the surface or absorbed through the mucous membrane for localized or systemic effects. Instillation can be used for various routes of administration including ocular (eye), nasal, auricular (ear), vaginal, and intra-articular (joint space) among others. The choice of instillation as a route of administration depends on the drug's properties, the desired therapeutic effect, and the patient's overall health status.
A pelvic infection, also known as pelvic inflammatory disease (PID), is a medical condition characterized by inflammation of the reproductive organs in females, including the uterus, fallopian tubes, ovaries, and surrounding tissues. It is often caused by an ascending infection from the cervix or vagina, commonly due to sexually transmitted bacteria such as Neisseria gonorrhoeae and Chlamydia trachomatis. However, other organisms can also cause pelvic infections.
Symptoms of pelvic infections may include lower abdominal pain, irregular menstrual bleeding, vaginal discharge with an unpleasant odor, fever, painful intercourse, and difficulty urinating. In some cases, pelvic infections may not cause any noticeable symptoms, making it challenging to diagnose the condition promptly.
If left untreated, pelvic infections can lead to serious complications such as chronic pelvic pain, infertility, ectopic pregnancy, and abscess formation in the reproductive organs. Treatment typically involves antibiotics to eradicate the infection, and in severe cases, hospitalization and surgical intervention may be necessary.
2-Propanol is a type of alcohol, also known as isopropanol or isopropyl alcohol. It is a colorless, flammable liquid with a characteristic odor. 2-Propanol is miscible with water and most organic solvents.
It is commonly used as a solvent and as an antiseptic or disinfectant, due to its ability to denature proteins and disrupt microbial cell membranes. In medical settings, 2-Propanol is often used as a skin sanitizer or hand rub to reduce the number of microorganisms on the skin.
Ingestion or prolonged exposure to 2-Propanol can cause irritation to the eyes, skin, and respiratory tract, and may lead to central nervous system depression, nausea, vomiting, and other symptoms. It is important to handle 2-Propanol with care and follow appropriate safety precautions when using it.
Antisepsis is the process of preventing or limiting the growth and reproduction of microorganisms (such as bacteria, fungi, and viruses) that can cause infection or disease. This is typically achieved through the use of antiseptic agents, which are substances that inhibit the growth of microorganisms when applied to living tissue or non-living material like surfaces.
Antiseptics work by either killing the microorganisms outright (bactericidal) or preventing them from reproducing and growing (bacteriostatic). They can be applied topically, in the form of creams, ointments, gels, sprays, or washes, to prevent infection in wounds, cuts, burns, or other types of skin damage. Antiseptics are also used in medical devices and equipment to maintain sterility and prevent cross-contamination during procedures.
Examples of antiseptic agents include alcohol, chlorhexidine, hydrogen peroxide, iodine, and povidone-iodine. The choice of antiseptic depends on the type of microorganism being targeted, the location and severity of the infection, and any potential adverse effects or interactions with other medications or medical conditions.
It's important to note that antisepsis is different from sterilization, which involves the complete destruction of all living organisms, including spores, using methods such as heat, radiation, or chemicals. Sterilization is typically used for surgical instruments and other medical equipment that come into direct contact with sterile tissues or bodily fluids during procedures.
Chyle is a milky, slightly opaque fluid that is present in the lymphatic system. It is formed in the small intestine during the digestion of food, particularly fats. Chyle consists of emulsified fat droplets (chylomicrons), proteins, electrolytes, and lymphocytes suspended in a watery solution. It is transported through the lacteals in the villi of the small intestine into the cisterna chyli and then to the thoracic duct, where it empties into the left subclavian vein. From there, it mixes with blood and circulates throughout the body. Chyle formation plays a crucial role in fat absorption and transportation in the human body.
Iodophors are antiseptic solutions or preparations that contain iodine complexed with a solubilizing agent, usually a nonionic surfactant. The most common example is povidone-iodine (polyvinylpyrrolidone-iodine). Iodophors are widely used for skin disinfection before surgical procedures and injections, as well as for the treatment of wounds and burns.
The advantage of iodophors over traditional tincture of iodine is that they provide a more sustained release of iodine, which results in a longer-lasting antimicrobial effect while being less irritating to the skin. The complexation with the solubilizing agent also helps to reduce staining of the skin and clothing compared to traditional iodine solutions.
Disinfectants are antimicrobial agents that are applied to non-living objects to destroy or irreversibly inactivate microorganisms, but not necessarily their spores. They are different from sterilizers, which kill all forms of life, and from antiseptics, which are used on living tissue. Disinfectants work by damaging the cell wall or membrane of the microorganism, disrupting its metabolism, or interfering with its ability to reproduce. Examples of disinfectants include alcohol, bleach, hydrogen peroxide, and quaternary ammonium compounds. They are commonly used in hospitals, laboratories, and other settings where the elimination of microorganisms is important for infection control. It's important to use disinfectants according to the manufacturer's instructions, as improper use can reduce their effectiveness or even increase the risk of infection.
Sodium hypochlorite is a chemical compound with the formula NaOCl. It is a pale greenish-yellow liquid that is highly reactive and unstable in its pure form. However, it is commonly available as a dilute aqueous solution known as bleach, which has the characteristic smell of chlorine.
In medical terms, sodium hypochlorite is widely used for its disinfectant and antiseptic properties. It is effective against a broad range of microorganisms, including bacteria, viruses, fungi, and spores. Sodium hypochlorite solution is commonly used to disinfect surfaces, medical instruments, and wounds.
When applied to wounds or skin infections, sodium hypochlorite can help reduce bacterial load, promote healing, and prevent infection. It is also a component of some mouthwashes and toothpastes, where it helps to kill bacteria and freshen breath. However, it can be irritating to the skin and mucous membranes, so it should be used with caution and at appropriate concentrations.
Disinfection is the process of eliminating or reducing harmful microorganisms from inanimate objects and surfaces through the use of chemicals, heat, or other methods. The goal of disinfection is to reduce the number of pathogens to a level that is considered safe for human health. Disinfection is an important step in preventing the spread of infectious diseases in healthcare settings, food processing facilities, and other environments where there is a risk of infection transmission.
It's important to note that disinfection is not the same as sterilization, which is the complete elimination of all microorganisms, including spores. Disinfection is generally less effective than sterilization but is often sufficient for most non-critical surfaces and objects. The choice between disinfection and sterilization depends on the level of risk associated with the item or surface being treated and the intended use of that item or surface.
Lymphatic diseases refer to a group of conditions that affect the lymphatic system, which is an important part of the immune and circulatory systems. The lymphatic system consists of a network of vessels, organs, and tissues that help to transport lymph fluid throughout the body, fight infection, and remove waste products.
Lymphatic diseases can be caused by various factors, including genetics, infections, cancer, and autoimmune disorders. Some common types of lymphatic diseases include:
1. Lymphedema: A condition that causes swelling in the arms or legs due to a blockage or damage in the lymphatic vessels.
2. Lymphoma: A type of cancer that affects the lymphatic system, including Hodgkin's and non-Hodgkin's lymphoma.
3. Infections: Certain bacterial and viral infections can affect the lymphatic system, such as tuberculosis, cat-scratch disease, and HIV/AIDS.
4. Autoimmune disorders: Conditions such as rheumatoid arthritis, lupus, and scleroderma can cause inflammation and damage to the lymphatic system.
5. Congenital abnormalities: Some people are born with abnormalities in their lymphatic system, such as malformations or missing lymph nodes.
Symptoms of lymphatic diseases may vary depending on the specific condition and its severity. Treatment options may include medication, physical therapy, surgery, or radiation therapy. It is important to seek medical attention if you experience symptoms of a lymphatic disease, as early diagnosis and treatment can improve outcomes.
In medical terms, the skin is the largest organ of the human body. It consists of two main layers: the epidermis (outer layer) and dermis (inner layer), as well as accessory structures like hair follicles, sweat glands, and oil glands. The skin plays a crucial role in protecting us from external factors such as bacteria, viruses, and environmental hazards, while also regulating body temperature and enabling the sense of touch.
An encyclopedia is a comprehensive reference work containing articles on various topics, usually arranged in alphabetical order. In the context of medicine, a medical encyclopedia is a collection of articles that provide information about a wide range of medical topics, including diseases and conditions, treatments, tests, procedures, and anatomy and physiology. Medical encyclopedias may be published in print or electronic formats and are often used as a starting point for researching medical topics. They can provide reliable and accurate information on medical subjects, making them useful resources for healthcare professionals, students, and patients alike. Some well-known examples of medical encyclopedias include the Merck Manual and the Stedman's Medical Dictionary.
Hexachlorophene is a synthetic antimicrobial compound, historically used for its broad-spectrum bacteriostatic properties. Its medical definition is as a white crystalline powder with a slight characteristic odor, soluble in alcohol, chloroform, and ether, and sparingly soluble in water. It has been used as a topical antiseptic and surgical scrub for its effectiveness against gram-positive bacteria, some fungi, and viruses. However, due to concerns about neurotoxicity, particularly in infants, its use is now largely restricted to medical applications that require extensive sterilization, such as certain types of wound care.