Bacterial infections antibiotics

D. Treatment of bacterial infections Antibiotics that selectively affect bacterial function and have minimal side effects in humans are usually selected to treat bacterial infections. Rifampicin, which inhibits the initiation of prokaryotic RNA synthesis, is used to treat tuberculosis. Streptomycin, tetracycline, chloramphenicol, and erythromycin inhibit protein synthesis on prokaiyotic ribosomes and are used for many infections. Chloramphenicol affects mitochondrial ribosomes and must be used with caution. 

Veterinary drugs are used to treat animals for bacterial infections (antibiotics) and parasitic infestations (anthelmintics, coccidiostats), to enhance growth (antibiotics, anabohcs, partitioning agents, thyrostats), to control fertility and reproduction (steroid hormones), or to alter behavior (tranquillizers and sedatives). Within each of the drug types there are different classes and methods for residue analysis are typically class specific (e.g., methods for the class of tetracycline antibiotics). In certain cases, mrdtiresidue methods are available that are broader than specific classes. 

Inchviduals with this condition have good health until a haemolytic crisis is precipitated by oxidative stress, such as bacterial infections, antibiotics, anrimalarial drugs, certain dyes, or the ingestion of fava beans (similar to broad beans). A blood film from a patient who has this condition will often show the presence of Heinz boches inside the RBCs, which result from the precipitation of oxidized, denatured haemoglobin. 

Luciferin includes a whole family of compounds whose heterocyclic structures vary fix>m one organism to another. Most luciferase enzymes use the same cofactors as metabolic processes (ATP, FMN, NADH), and bioluminescence is easily associated with other types of Inological reactions for analytical applications. Firefly ludferase is used tt> follow processes that use adenosine triphosphate (ATP) as a cofactor, for example, the measurement of biomass, the detection of a bacterial infection, antibiotic assays, and the monitoring of other enzymatic reactions that consume or produce ATP. Luciferase catalyses all these reactions according to the following overall reaction scheme ... 

P-Lactams. AH 3-lactams are chemically characterized by having a 3-lactam ring. Substmcture groups are the penicillins, cephalosporias, carbapenems, monobactams, nocardicias, and clavulanic acid. Commercially this family is the most important group of antibiotics used to control bacterial infections. The 3-lactams act by inhibition of bacterial cell wall biosynthesis. 

P-lactam antibiotics, exert thek antibacterial effect by interfering with the synthesis of the bacterial cell wall. These antibiotics tend to be "kreversible" inhibitors of cell wall biosynthesis and they are usually bactericidal at concentrations close to thek bacteriostatic levels. Cephalospotins are widely used for treating bacterial infections. They are highly effective antibiotics and have low toxicity. 

Frequendy, the treatment of helminthic diseases requites adjunct medication. Allergic reactions are commonly seen as a result of tissue invasion by worms or as a consequence of anthelmintic therapy. Antihistamines and corticosteroids may be necessary adjuncts to therapy. Anemia, indigestion, and secondary bacterial infections can also occur and may requite concomitant therapy with hematopoietic drugs and appropriate antibiotics. 

The importance of the penicillins as a class of heterocyclic compounds derives primarily from their effectiveness in the treatment of bacterial infections in mammals (especially humans). It has been estimated that, in 1980, the worldwide production of antibiotics was 25 000 tons and, of this, approximately 17 000 tons were penicillins (81MI51103). The Food and Drug Administration has estimated that, in 1979 in the U.S.A., 30.1 x 10 prescriptions of penicillin V and 44.3 x 10 prescriptions of ampicillin/amoxicillin were dispensed. This level of usage indicates that, compared to other methods of dealing with bacterial infection, the cost-benefit properties of penicillin therapy are particularly favorable. Stated differently, penicillin treatment leads to the elimination of the pathogen in a relatively high percentage of cases of bacterial infection at a relatively low cost to the patient in terms of toxic reactions and financial resources. 

Just as fflnides are more stable than esters, lactfflns are more stable than lactones. Thus, although p-lactones are rare (Section 19.15), p-lactfflns are fflnong the best known products of the phaiinaceutical industry. The penicillin and cephalosporin antibiotics, which are so useful in treating bacterial infections, are p-lactfflns and are customarily refeired to as (3-lactam antibiotics. 

Although the advent of the antibiotics revolutionized the treatment of bacterial infections, tuberculosis has proven unusually resistant to chemotherapeutic attack. Although many antibiotics are effective to some extent in arresting the progress of... 

Chloramphenicol, a powerful antibiotic isolated in 1949 from the Streptomyces venezuelae bacterium, is active against a broad spectrum of bacterial infections and is particularly valuable against typhoid fever. Assign R,S configurations to the chirality centers in chloramphenicol. 

Penicillin (MM = 356 g/md), an antibiotic often used to treat bacterial infections, is a weak acid. ItsfQis 1.7 X 10-3. Calculate [H+] in solutions prepared by adding enough water to the following to make 725 ml.. 

The discovery and production of antibiotics has been of tremendous importance to human and animal health care. Prior to their discovery about half a century ago, many bacterial infections caused debilitating diseases and fatalities were high. The discovery of antibiotics was a major step in the treatment of infectious diseases, especially those caused by bacteria. Today about 50,000 tonnes of antibiotics are produced annually. About a third of this consists of penicillins, whilst tetracyclines make up about a quarter of the market. 

Tetracycline and its derivative doxycycline are antibiotics widely used in the treatment of bacterial infections. They also exert an antimalarial activity. Tetracyclines inhibit the binding of aminoacyl-tRNA to the ribosome during protein synthesis. 

The use of antibiotics is not recommended, except for the treatment of infectious exacerbations of COPD and other bacterial infections. Influenza vaccines decrease illness and death in COPD patients. Pneumococcal vaccination is also recommended. 

As with all drugs, the specific side effects of the quinolones must be considered when they are chosen for treatment of bacterial infections [5]. Reactions of the gastrointestinal tract and the central neivous system are the most often observed adverse effects during therapy with quinolones. It should be underlined, however, that compared with many other antimicrobials, diarrhea is less frequently observed during quinolone treatment. Antibiotic-associated colitis has been observed rarely during quinolone therapy. Similarly, hypersensitivity reactions, as observed during therapy with penicillins and other (3-lactams, is less frequently caused by quinolones. Some other risks of quinolone therapy have been defined and must be considered if a drug from this class is chosen for treatment of bacterial infections. 

Before therapy is begun, culture and sensitivity tests (see Chap. 7) are performed to determine which antibiotic will best control the infection. These drug are of no value in the treatment of infections caused by a virus or fungus. There may be times when a secondary bacterial infection has occurred or potentially will occur when the patient has a fungal or viral infection. The primary health care provider may then order one of die... 

When considering anti-infective therapy, one first thinks of a curative treatment, aiming at the rapid elimination of the pathogen from the human organism. This concept holds true for the treatment of most bacterial infections with antibiotics however, in the case of antiviral therapy, a curative treatment is the exception rather than the rule. Many human virus infections are characterized by an acute, self-limiting... 

At the present time we are faced with the real and frightening threat of a post-antibiotic era in years to come, where our existing antibiotic arsenal will become largely ineffective against bacterial infections. 

Antibiotics are used to treat bacterial infection [41]. Some antibiotics act directly on cell membranes of micro-organisms, with consequent alteration of permeability and leakage of intracellular components. Antibiotics affect cell membranes and thus also the liquid membrane, with the possibility of change in oscillation. 

The major successes in treating bacterial infections that were achieved by the antibiotics discovered in the middle part of the last century are now under severe threat from the emergence of resistant strains. Very few new classes of antibacterial have been created in the past 20 years. Peptide deformylase represents a new biochemical target and clinical candidates are beginning to emerge. Chapter 3 reviews progress to date. 

Routine antibiotic use is not warranted because the primary infectious agents associated with asthma exacerbations are viruses.2,3 Antibiotics should be reserved for situations when bacterial infection is strongly suspected (e.g., fever and purulent sputum, pneumonia, and suspected sinusitis). 

The role of bacterial infections in COPD exacerbations is controversial, and there are limited data on the efficacy of antibiotics in treating COPD exacerbations. Recent studies suggest that bacteria cause 40% to 50% of acute exacerbations.31 Antibiotics should be used in patients with COPD exacerbations who have either of the following characteristics (1) at least two of three cardinal symptoms increased dyspnea, sputum volume, or sputum purulence or (2) a severe exacerbation requiring mechanical ventilation.2... 

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