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Tigecycline
Tigecycline, sold under the brand name Tygacil, is a tetracycline antibiotic medication for a number of bacterial infections. It is a glycylcycline class drug that is administered intravenously. It was developed in response to the growing rate of antibiotic resistant bacteria such as ''Staphylococcus aureus'', ''Acinetobacter baumannii'', and '' E. coli''. As a tetracycline derivative antibiotic, its structural modifications has expanded its therapeutic activity to include Gram-positive and Gram-negative organisms, including those of multi-drug resistance. It was given a U.S. Food and Drug Administration (FDA) fast-track approval and was approved on 17 June 2005. It was approved for medical use in the European Union in April 2006. It was removed from the World Health Organization's List of Essential Medicines in 2019. The World Health Organization classifies tigecycline as critically important for human medicine. Medical uses Antibacterial use Tigecycline is used to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycylcycline
Glycylcyclines are a class of antibiotics derived from tetracycline. These tetracycline analogues are specifically designed to overcome two common mechanisms of Tetracycline#Mechanism and resistance, tetracycline resistance, namely resistance mediated by acquired Efflux (microbiology), efflux pumps and/or ribosomal protection. Presently, tigecycline is the only glycylcycline approved for antibiotic use. History The development of these agents was spurred by the increasing prevalence of bacteria resistant to tetracyclines. These agents were first synthesized in the early 1990s by making modifications to the tetracyclines. By adding a bulky N,N-dimethylglycylamido side chain to position 9 of minocycline, the compound became less susceptible to tetracycline resistance mediated by acquired efflux pumps and/or ribosomal protection. Further development of this initial work led to the creation of tigecycline, the first glycylcycline available for clinical use. Approvals *Tigecycli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetracycline Antibiotic
Tetracyclines are a group of broad-spectrum antibiotic compounds that have a common basic structure and are either isolated directly from several species of ''Streptomyces'' bacteria or produced semi-synthetically from those isolated compounds. Tetracycline molecules comprise a linear fused tetracyclic nucleus (rings designated A, B, C and D) to which a variety of functional groups are attached. Tetracyclines are named after their four ("tetra-") hydrocarbon rings ("-cycl-") derivation ("-ine"). They are defined as a subclass of polyketides, having an octahydrotetracene-2-carboxamide skeleton and are known as derivative (chemistry), derivatives of polycyclic naphthacene carboxamide. While all tetracyclines have a common structure, they differ from each other by the presence of chloro, methyl, and hydroxyl groups. These chemical modification, modifications do not change their broad antibacterial activity, but do affect pharmacological properties such as half-life and binding to pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intravenous Therapy
Intravenous therapy (abbreviated as IV therapy) is a medical technique that administers fluids, medications and nutrients directly into a person's vein. The intravenous route of administration is commonly used for rehydration or to provide nutrients for those who cannot, or will not—due to reduced mental states or otherwise—consume food or water per os, by mouth. It may also be used to administer pharmaceutical drug, medications or other medical therapy such as blood transfusion, blood products or electrolytes to correct electrolyte imbalances. Attempts at providing intravenous therapy have been recorded as early as the 1400s, but the practice did not become widespread until the 1900s after the development of techniques for safe, effective use. The intravenous route is the fastest way to deliver medications and fluid replacement throughout the body as they are introduced directly into the circulatory system and thus quickly distributed. For this reason, the intravenous route ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streptococcus Agalactiae
''Streptococcus agalactiae'' (also known as group B streptococcus or GBS) is a gram-positive coccus (round bacterium) with a tendency to form chains (as reflected by the genus name ''Streptococcus''). It is a beta-hemolytic, catalase-negative, and facultative anaerobe. ''S. agalactiae'' is the most common human pathogen of streptococci belonging to group B of the Rebecca Lancefield classification of streptococci. GBS are surrounded by a bacterial capsule composed of polysaccharides (exopolysaccharide). The species is subclassified into ten serotypes (Ia, Ib, II–IX) depending on the immunologic reactivity of their polysaccharide capsule. The plural term group B streptococci (referring to the serotypes) and the singular term group B streptococcus (referring to the single species) are both commonly used synonymously with ''S. agalactiae'' even though '' S. halichoeri'' and '' S. pseudoporcinus'' are also group B Streptococci. These species test positive as group B, but are not fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streptococcus Pneumoniae
''Streptococcus pneumoniae'', or pneumococcus, is a Gram-positive, spherical bacteria, hemolysis (microbiology), alpha-hemolytic member of the genus ''Streptococcus''. ''S. pneumoniae'' cells are usually found in pairs (diplococci) and do not form Bacterial morphological plasticity, spores and are non motile. As a significant human pathogenic bacterium ''S. pneumoniae'' was recognized as a major cause of pneumonia in the late 19th century, and is the subject of many humoral immunity studies. ''Streptococcus pneumoniae'' resides asymptomatically in healthy carriers typically colonizing the respiratory tract, sinuses, and nasopharynx, nasal cavity. However, in susceptible individuals with immunocompromised, weaker immune systems, such as the elderly and young children, the bacterium may become pathogenic and spread to other locations to cause disease. It spreads by direct person-to-person contact via respiratory droplets and by auto inoculation in persons carrying the bacteria in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peptostreptococcus
''Peptostreptococcus'' is a genus of anaerobic, Gram-positive, non-spore forming bacteria. The cells are small, spherical, and can occur in short chains, in pairs or individually. They typically move using cilia. ''Peptostreptococcus'' are slow-growing bacteria with increasing resistance to antimicrobial drugs. ''Peptostreptococcus'' is a normal inhabitant of the healthy lower reproductive tract of women. Pathogenesis ''Peptostreptococcus'' species are commensal organisms in humans, living predominantly in the mouth, skin, gastrointestinal, vagina and urinary tracts, and are members of the gut microbiota. Under immunosuppressed or traumatic conditions these organisms can become pathogenic, as well as septicemic, harming their host. ''Peptostreptococcus'' can cause brain, liver, breast, and lung abscesses, as well as generalized necrotizing soft tissue infections. They participate in mixed anaerobic infections, a term which is used to describe infections that are caused by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clostridium Perfringens
''Clostridium perfringens'' (formerly known as ''C. welchii'', or ''Bacillus welchii'') is a Gram-positive, bacillus (rod-shaped), anaerobic, spore-forming pathogenic bacterium of the genus '' Clostridium''. ''C. perfringens'' is ever-present in nature and can be found as a normal component of decaying vegetation, marine sediment, the intestinal tract of humans and other vertebrates, insects, and soil. It has the shortest reported generation time of any organism at 6.3 minutes in thioglycolate medium. ''Clostridium perfringens'' is one of the most common causes of food poisoning in the United States, alongside norovirus, ''Salmonella'', '' Campylobacter'', and ''Staphylococcus aureus''. However, it can sometimes be ingested and cause no harm. Infections induced by ''C. perfringens'' are associated with tissue necrosis, bacteremia, emphysematous cholecystitis, and gas gangrene, which is also known as clostridial myonecrosis. The specific name, ''perfringens,'' is derived ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteroides Vulgatus
''Bacteroides'' is a genus of Gram-negative, obligate anaerobic bacteria. ''Bacteroides'' species are non endospore–forming bacilli, and may be either motile or nonmotile, depending on the species. The DNA base composition is 40–48% GC. Unusual in bacterial organisms, ''Bacteroides'' membranes contain sphingolipids. They also contain meso-diaminopimelic acid in their peptidoglycan layer. ''Bacteroides'' species are normally mutualistic, making up the most substantial portion of the mammalian gastrointestinal microbiota, where they play a fundamental role in processing of complex molecules to simpler ones in the host intestine. As many as 1010–1011 cells per gram of human feces have been reported. They can use simple sugars when available; however, the main sources of energy for ''Bacteroides'' species in the gut are complex host-derived and plant glycans. Studies indicate that long-term diet is strongly associated with the gut microbiome composition—those who eat a h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteroides Thetaiotaomicron
''Bacteroides thetaiotaomicron'' is a Gram-negative, obligate anaerobic bacterium and a prominent member of the human gut microbiota, particularly within the large intestine. ''B. thetaiotaomicron'' belongs to the ''Bacteroides'' genus – a group that is known for its role in the complex microbial community of the gut microbiota. Its proteome, consisting of 4,779 members, includes a system for obtaining and breaking down dietary polysaccharides that would otherwise be difficult to digest for the human body. The bacterium encodes for enzymes such as glycoside hydrolases and polysaccharide lyases, allowing it to break down dietary fibers, such as cellulose and hemicellulose, into fermentable substrates. This metabolic activity generates short-chain fatty acids (SCFAs) like acetate and propionate, which are absorbed by the host and provide critical energy sources for colonic cells. ''B. thetaiotaomicron'' is an opportunistic pathogen and may become virulent in immunocompromised in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Klebsiella Oxytoca
''Klebsiella oxytoca'' is a Gram-negative, rod-shaped bacterium that is closely related to '' K. pneumoniae'', from which it is distinguished by being indole-positive; it also has slightly different growth characteristics in that it is able to grow on melezitose, but not 3-hydroxybutyrate. It was first described in 1886 when it was isolated from sour milk and named ''Bacillus oxytocus perniciosus'' (from Greek ''oxus'' 'sour' + ''-tokos'' 'producing'). ''Klebsiella oxytoca'' is characterized by negative methyl red, positive VP, positive citrate, urea and TSI gas production, is AA, and negative for TSI sulfide, DNAse, growth on sulfide-indole motility medium and the phenylalanine deaminase test. It is a diazotroph, able to colonise plant hosts and fix atmospheric nitrogen into a form which the plant can use. Association of ''K. oxytoca'' with the barley rhizosphere during an entire vegetative period has been demonstrated. The bacteria adhere strongly to root hairs, and less stro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Citrobacter Freundii
''Citrobacter'' is a genus of Gram-negative, aerobic, rod-shaped coliform bacteria of the Enterobacteriaceae family. ''Citrobacter'' spp. cause opportunistic infections (including urinary tract infections, gastroenteritis, and bacteremia). Microbiology Microbial biochemistry The species ''C. amalonaticus'', '' C. koseri'', and '' C. freundii'' can use citrate as a sole carbon source. ''Citrobacter'' species are differentiated by their ability to convert tryptophan to indole (''C. koseri'' is the only citrobacter to be commonly indole-positive), ferment lactose (''C. koseri'' is a lactose fermentor), and use malonate. ''Citrobacter'' shows the ability to accumulate uranium by building phosphate complexes. Environmental microbiology These bacteria can be found almost everywhere in soil, water, wastewater, etc. They can also be found in the human intestine. Clinical significance Citrobacter are considered opportunistic nosocomial pathogens, typically associated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteroides Fragilis
''Bacteroides fragilis'' is an anaerobic, Gram-negative, pleomorphic to rod-shaped bacterium. It is part of the normal microbiota of the human colon and is generally commensal, but can cause infection if displaced into the bloodstream or surrounding tissue following surgery, disease, or trauma. Habitat ''Bacteroides fragilis'' resides in the human gastrointestinal tract and is essential to healthy gastrointestinal function such as mucosal immunity and host nutrition. As a mesophile, optimal growth occurs at 37 °C and a pH around 7. Morphology Cells of ''B. fragilis'' are rod-shaped to pleomorphic with a cell size range of 0.5–1.5 × 1.0–6.0 μm.''B. fragilis'' is a Gram-negative bacterium and does not possess flagella or cilia making it immotile. However, it does utilize peritrichous fimbriae for adhesion to other molecular structures. ''B. fragilis'' also utilizes a complex series of surface proteins, lipopolysaccharide chains, and outer membrane vesicles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
