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Carbenicillin
Carbenicillin is a bactericidal antibiotic belonging to the carboxypenicillin subgroup of the penicillins. It was discovered by scientists at Beecham and marketed as Pyopen. It has Gram-negative coverage which includes ''Pseudomonas aeruginosa'' but limited Gram-positive coverage. The carboxypenicillins are susceptible to degradation by beta-lactamase enzymes, although they are more resistant than ampicillin to degradation. Carbenicillin is also more stable at lower pH than ampicillin. Pharmacology The antibiotic is highly soluble in water and is acid-labile. A typical lab working concentration is 50 to 100 μg per mL. It is a semi-synthetic analogue of the naturally occurring benzylpenicillin. Carbenicillin at high doses can cause bleeding. Use of carbenicillin can cause hypokalemia by promoting potassium loss at the distal convoluted tubule of the kidney. In molecular biology, carbenicillin may be preferred as a selecting agent (see plasmid stabilisation technology) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboxypenicillin
The carboxypenicillins are a group of antibiotics. They belong to the penicillin family and comprise the members carbenicillin and ticarcillin. Chemical structure The carboxypenicillins feature the beta-lactam backbone of all penicillins but also feature a carboxylic acid or ester, carboxylic acid ester group in the variable side-chain. Spectrum The carboxypenicillins exhibit activity against Gram negative organisms including ''Pseudomonas aeruginosa'' and ''Proteus (bacterium), Proteus'' species. They are inactive against certain Gram positive pathogens such as ''Staphylococcus aureus'', ''Enterococcus faecalis'', and ''L. monocytogenes''. The carboxypenicillins are beta-lactamase sensitive. See also * Aminopenicillin * Temocillin References {{Cell wall disruptive antibiotics Penicillins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Penicillins
Penicillins (P, PCN or PEN) are a group of β-lactam antibiotics originally obtained from ''Penicillium'' moulds, principally '' P. chrysogenum'' and '' P. rubens''. Most penicillins in clinical use are synthesised by '' P. chrysogenum'' using deep tank fermentation and then purified. A number of natural penicillins have been discovered, but only two purified compounds are in clinical use: penicillin G ( intramuscular or intravenous use) and penicillin V (given by mouth). Penicillins were among the first medications to be effective against many bacterial infections caused by staphylococci and streptococci. They are still widely used today for various bacterial infections, though many types of bacteria have developed resistance following extensive use. Ten percent of the population claims penicillin allergies, but because the frequency of positive skin test results decreases by 10% with each year of avoidance, 90% of these patients can eventually tolerate penicillin. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Penicillin
Penicillins (P, PCN or PEN) are a group of beta-lactam antibiotic, β-lactam antibiotics originally obtained from ''Penicillium'' Mold (fungus), moulds, principally ''Penicillium chrysogenum, P. chrysogenum'' and ''Penicillium rubens, P. rubens''. Most penicillins in clinical use are synthesised by ''Penicillium chrysogenum, P. chrysogenum'' using industrial fermentation, deep tank fermentation and then purified. A number of natural penicillins have been discovered, but only two purified compounds are in clinical use: benzylpenicillin, penicillin G (intramuscular injection, intramuscular or Intravenous therapy, intravenous use) and phenoxymethylpenicillin, penicillin V (given by mouth). Penicillins were among the first medications to be effective against many bacterial infections caused by staphylococcus, staphylococci and streptococcus, streptococci. They are still widely used today for various bacterial infections, though many types of bacteria have developed antibiotic res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ampicillin
Ampicillin is an antibiotic belonging to the aminopenicillin class of the penicillin family. The drug is used to prevent and treat several bacterial infections, such as respiratory tract infections, urinary tract infections, meningitis, salmonellosis, and endocarditis. It may also be used to prevent group B streptococcal infection in newborns. It is used by mouth, by injection into a muscle, or intravenously. Common side effects include rash, nausea, and diarrhea. It should not be used in people who are allergic to penicillin. Serious side effects may include ''Clostridioides difficile'' colitis or anaphylaxis. While usable in those with kidney problems, the dose may need to be decreased. Its use during pregnancy and breastfeeding appears to be generally safe. Ampicillin was discovered in 1958 and came into commercial use in 1961. It is on the World Health Organization's List of Essential Medicines. The World Health Organization classifies ampicillin as critical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasmid Stabilisation Technology
A toxin-antitoxin system consists of a "toxin" and a corresponding "antitoxin", usually encoded by closely linked genes. The toxin is usually a protein while the antitoxin can be a protein or an RNA. Toxin-antitoxin systems are widely distributed in prokaryotes, and organisms often have them in multiple copies. When these systems are contained on plasmids – transferable genetic elements – they ensure that only the daughter cells that inherit the plasmid survive after cell division. If the plasmid is absent in a daughter cell, the unstable antitoxin is degraded and the stable toxic protein kills the new cell; this is known as 'post-segregational killing' (PSK). Toxin-antitoxin systems are typically classified according to how the antitoxin neutralises the toxin. In a type I toxin-antitoxin system, the translation of messenger RNA (mRNA) that encodes the toxin is inhibited by the binding of a small non-coding RNA antitoxin that binds the toxin mRNA. The toxic protein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Biology
Molecular biology is a branch of biology that seeks to understand the molecule, molecular basis of biological activity in and between Cell (biology), cells, including biomolecule, biomolecular synthesis, modification, mechanisms, and interactions. Though cells and other microscopic structures had been observed in living organisms as early as the 18th century, a detailed understanding of the mechanisms and interactions governing their behavior did not emerge until the 20th century, when technologies used in physics and chemistry had advanced sufficiently to permit their application in the biological sciences. The term 'molecular biology' was first used in 1945 by the English physicist William Astbury, who described it as an approach focused on discerning the underpinnings of biological phenomena—i.e. uncovering the physical and chemical structures and properties of biological molecules, as well as their interactions with other molecules and how these interactions explain observ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Distal Convoluted Tubule
The distal convoluted tubule (DCT) is a portion of kidney nephron between the loop of Henle and the collecting tubule. Physiology It is partly responsible for the regulation of potassium, sodium, calcium, and pH. On its apical surface (lumen side), cells of the DCT have a thiazide-sensitive Na-Cl cotransporter and are permeable to Ca, via the TRPV5 channel. On the basolateral surface (peritubular capillary side) there is an ATP-dependent Na/K antiporter pump, a secondary active Na/Ca transporter, and an ATP dependent Ca transporter. The basolateral ATP dependent Na/K pump produces the gradient for Na to be absorbed from the apical surface via the Na/Cl symporter, and for Ca to be reclaimed into the blood by the Na/Ca basolateral antiporter. * It regulates pH by absorbing bicarbonate and secreting protons (H+) into the filtrate, or by absorbing protons and secreting bicarbonate into the filtrate. * Sodium and potassium levels are controlled by secreting K+ and absorbing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium
Potassium is a chemical element; it has Symbol (chemistry), symbol K (from Neo-Latin ) and atomic number19. It is a silvery white metal that is soft enough to easily cut with a knife. Potassium metal reacts rapidly with atmospheric oxygen to form flaky white potassium peroxide in only seconds of exposure. It was first isolated from potash, the ashes of plants, from which its name derives. In the periodic table, potassium is one of the alkali metals, all of which have a single valence electron in the outer electron shell, which is easily removed to create cation, an ion with a positive charge (which combines with anions to form salts). In nature, potassium occurs only in ionic salts. Elemental potassium reacts vigorously with water, generating sufficient heat to ignite hydrogen emitted in the reaction, and burning with a lilac-flame color, colored flame. It is found dissolved in seawater (which is 0.04% potassium by weight), and occurs in many minerals such as orthoclase, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypokalemia
Hypokalemia is a low level of potassium (K+) in the blood serum. Mild low potassium does not typically cause symptoms. Symptoms may include feeling tired, leg cramps, weakness, and constipation. Low potassium also increases the risk of an abnormal heart rhythm, which is often too slow and can cause cardiac arrest. Causes of hypokalemia include vomiting, diarrhea, medications like furosemide and steroids, dialysis, diabetes insipidus, hyperaldosteronism, hypomagnesemia, and not enough intake in the diet. Normal potassium levels in humans are between 3.5 and 5.0 mmol/L (3.5 and 5.0 mEq/L) with levels below 3.5 mmol/L defined as hypokalemia. It is classified as severe when levels are less than 2.5 mmol/L. Low levels may also be suspected based on an electrocardiogram (ECG). The opposite state is called hyperkalemia that means high level of potassium in the blood serum. The speed at which potassium should be replaced depends on whether or not there are symptom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzylpenicillin
Benzylpenicillin, also known as penicillin G (PenG) or BENPEN, is an antibiotic used to treat a number of bacterial infections. This includes pneumonia, strep throat, syphilis, necrotizing enterocolitis, diphtheria, gas gangrene, leptospirosis, cellulitis, and tetanus. It is not a first-line agent for pneumococcal meningitis. Due to benzylpenicillin's limited bioavailability for oral medications, it is generally taken as an injection in the form of a sodium, potassium, benzathine, or procaine salt. Benzylpenicillin is given by injection into a vein or muscle. Two long-acting forms benzathine benzylpenicillin and procaine benzylpenicillin are available for use by injection into a muscle only. Side effects include diarrhea, seizures, and allergic reactions including anaphylaxis. When used to treat syphilis or Lyme disease a reaction known as Jarisch–Herxheimer may occur. It is not recommended in those with a history of penicillin allergy. Use during pregnancy is gene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Breast Milk
Breast milk (sometimes spelled as breastmilk) or mother's milk is milk produced by the mammary glands in the breasts of women. Breast milk is the primary source of nutrition for newborn infants, comprising fats, proteins, carbohydrates, and a varying composition of minerals and vitamins. Breast milk also contains substances that help protect an infant against infection and inflammation, such as Human milk microbiome, symbiotic bacteria and other microorganisms and immunoglobulin A, whilst also contributing to the healthy development of the infant's immune system and gut microbiome. Use and methods of consumption The World Health Organization (WHO) and UNICEF recommend Breastfeeding#Duration and exclusivity, exclusive breastfeeding with breast milk for the first six months of an infant’s life. This period is followed by the incorporation of nutritionally adequate and safe complementary solid foods at six months, a stage when an infant’s nutrient and energy requirements start ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beta-lactamase
Beta-lactamases (β-lactamases) are enzymes () produced by bacteria that provide multi-resistance to beta-lactam antibiotics such as penicillins, cephalosporins, cephamycins, monobactams and carbapenems ( ertapenem), although carbapenems are relatively resistant to beta-lactamase. Beta-lactamase provides antibiotic resistance by breaking the antibiotics' structure. These antibiotics all have a common element in their molecular structure: a four-atom ring known as a beta-lactam (β-lactam) ring. Through hydrolysis, the enzyme lactamase breaks the β-lactam ring open, deactivating the molecule's antibacterial properties. Beta-lactamases produced by gram-negative bacteria are usually secreted, especially when antibiotics are present in the environment. Structure The structure of a '' Streptomyces'' serine β-lactamase (SBLs) is given by . The alpha-beta fold () resembles that of a DD-transpeptidase, from which the enzyme is thought to have evolved. β-lactam antibio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
