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PubMed1983

Antibiotic activity in peritoneal dialysate.

There are few studies investigating whether antibiotics added to 30% glucose concentrate preserve their activity in the delivered dialysate. Using a Drake-Willock proportioning system, samples were obtained from the "to" patient path at ten minutes after starting and at four hours. Samples were tested for minimal inhibitory dilution (MID) against Escherichia coli and Staphylococcus aureus. Antibiotics evaluated included amikacin, tobramycin, gentamicin, cephalothin, cefamandole, moxalactam, ampicillin, penicillin, carbenicillin, and vancomycin. In all antibiotics studied, similar MIDs were obtained at the ten-minute and four-hour samples. Compared to saline, dialysate significantly impaired the antibiotic activity (a difference of two or more tube dilutions) of all antimicrobial agents except amikacin and vancomycin.

Anti-Bacterial Agents↗
PubMed2001

Screening of antibiotic resistant inhibitors from local plant materials against two different strains of Pseudomonas aeruginosa.

The methanolic extracts of 19 Jordanian plants were combined with seven different antibiotics and applied to check the inhibitory effects of the combination on the resistance of Pseudomonas aeruginosa. A resistant strain of Ps. aeruginosa, which was isolated from a patient and a standard strain of the same microorganism were used in this study. Our results showed that there are significant variations in the effects of some combinations used on the resistant and the standard strains probably due to structural changes. Almost all the plant materials used in combination with penicillin G and erythromycin allowed full growth of the standard strain, while the combination with some plant materials like Gundelia tournefortii L. and Lepidium sativum L. inhibited the growth of the resistant strain. Chloramphenicol, gentamicin and cephalosporin can be given advantageously with almost all the plant materials used with few exceptions on the resistant strain. Nalidixic acid activity was improved significantly when combined with all plant materials and tested on standard strain. On the other hand, its activity on the resistant strain was slightly improved using the same combinations.

Drug Evaluation, Preclinical↗
PubMed1999

In vitro inhibition of drug-resistant and drug-sensitive strains of Mycobacterium tuberculosis by ethnobotanically selected South African plants.

Twenty South African medicinal plants used to treat pulmonary diseases were screened for activity against drug-resistant and drug-sensitive strains of Mycobacterium tuberculosis. A preliminary screening of acetone and water plant extracts against a drug-sensitive strain of Mycobacterium tuberculosis, H37Rv, was done by the agar plate method. Fourteen of the 20 acetone extracts showed inhibitory activity at a concentration of 0.5 mg/ml against this strain. Acetone as well as water extracts of Cryptocarya latifolia, Euclea natalensis, Helichrysum melanacme, Nidorella anomala and Thymus vulgaris inhibited the growth of M. tuberculosis. Given the activity of 14 acetone extracts at 0.5 mg/ml against the drug-sensitive strain by the agar plate method, a further study was done employing a rapid radiometric method to confirm the inhibitory activity. These active acetone extracts were screened against the H37Rv strain as well as a strain resistant to the drugs isoniazid and rifampin. The minimal inhibitory concentration of Croton pseudopulchellus, Ekebergia capensis, Euclea natalensis, Nidorella anomala and Polygala myrtifolia was 0.1 mg/ml against the H37Rv strain by the radiometric method. Extracts of Chenopodium ambrosioides, Ekebergia capensis, Euclea natalensis, Helichrysum melanacme, Nidorella anomala and Polygala myrtifolia were active against the resistant strain at 0.1 mg/ml. Eight plants showed activity against both strains at a concentration of 1.0 mg/ml.

Acetone↗
PubMed1998

The role of copper on ethambutol's antimicrobial action and implications for ethambutol-induced optic neuropathy.

The principal side effect of the antimycobacterial agent ethambutol (EMB) is an optic neuropathy with clinical features very similar to a mitochondrial hereditary optic neuropathy (Leber's). The mechanism of EMB-induced optic neuropathy may be EMB's chelation of copper, thereby precluding normal cytochrome c oxidase activity and mitochondrial metabolism in the optic nerve. Before attempting to use therapeutic copper to replenish endogenous stores in an attempt to preclude EMB-induced optic neuropathy, we wished to determine whether EMB is still effective against mycobacteria in the presence of copper. EMB and copper, alone and in combination, were tested against six strains of Mycobacterium tuberculosis and five strains of Mycobacterium avium using a radiometric broth macrodilution assay. Copper did not effect EMB's antimicrobial actions against either species of mycobacteria. This in vitro study suggests that if copper were given to patients to prevent EMB-induced optic neuropathy, it would not compromise EMB's bacteriostatic properties.

Antitubercular Agents↗
PubMed1998

The bactericidal activity of clarithromycin versus ampicillin alone and in combination with omeprazole and/or bismuth against clarithromycin-susceptible and clarithromycin-resistant strains of Helicobacter pylori.

We evaluated the in vitro bactericidal effect of clarithromycin versus ampicillin alone and in combination against clarithromycin-sensitive and clarithromycin-resistant strains of Helicobacter pylori. No combination containing clarithromycin achieved complete bactericidal effect against clarithromycin-resistant strains. Complete bactericidal effect was achieved for all strains by triple-agent combinations that contained bismuth, omeprazole, and relatively high concentrations of ampicillin. These in vitro results demonstrate the additive bactericidal activity provided by a combination of agents for the eradication of H. pylori. Bismuth may play a particularly important role in the bactericidal effect.

Ampicillin↗
PubMed2003

Antifungal drugs used for systemic mycoses.

Table 1 summarizes the antifungal agents commonly used for the treatment of systemic mycoses. The treatment of these conditions remains a challenge. This is particularly the case with infections in neutropenic patients where mortality rates remain high despite the development of new drugs and the evaluation of drug combinations. Much attention has been focused on the development of new antifungal drugs that can provide a solution to this problem without concurrent toxicity and without the risk of drug resistance.

Administration, Oral↗
PubMed2004

Antimicrobial therapy and resistance in dermatologic pathogens of the elderly.

Dermatologic infections are treated to improve the elderly patient's quality of life and prevent disability and death. Pharmacokinetic changes, social issues, and the risk for adverse effects and drug interactions, however, increase the challenge to achieve successful treatment of those over age 65 as compared with younger patients. This challenge grows ever larger when coupled with the increasing trends of resistance among bacteria and fungi. The clinician can effectively face this challenge through careful consideration of diagnosis, patient risk factors, antimicrobial pharmacology, and resistance patterns.

Aged↗
PubMed2000

[Glycopeptides].

OBJECTIVES: To review pharmacology, pharmacokinetic and therapeutic use of glycopeptides in intensive care units. DATA SOURCES: Extraction from Medline database of French and English articles on glycopeptides and search along with major review articles. DATA SELECTION: The collected articles were reviewed and selected according to their quality and originality. The more recent data were selected. DATA SYNTHESIS: Glycopeptides are bactericidal antibiotics which are only active against Gram positive species acting by inhibiting peptidoglycan synthesis. They had been in clinical use for almost 30 years without high-level resistance underlining. For ten years, there have been disturbing reports of first, resistance to vancomycin in enterococcal species and more recently in strains of Staphylococcus aureus by complex and large mechanisms of action. This new resistances may lead to a therapeutic impasse and a fatal issue for infected patients. The only response to this situation is the respect of prescription rules and the careful use of antibiotics. CONCLUSION: Considering their spectrum, glycopeptides are an antibiotic family which importance is fundamental to treat infected patients of intensive care units. Staff members of intensive care units are responsible for their good use.

Anti-Bacterial Agents↗
PubMed1997

Defining intravascular catheter-related infections: a plea for uniformity.

This article defines the complex interaction between catheterized patients and invading microbial pathogens. Catheter colonization reflects significant growth of a microbe on a catheter component. Localized intravascular catheter-related infection denotes infection at the exit site, tunnel tract, or pocket, in the absence of bloodstream infection. Systemic intravascular catheter-related infection is a complication of colonization or localized infection, usually documented by invasion of the bloodstream. Catheter sepsis is a systemic infection that is difficult to define because symptoms associated with bloodstream infection caused by the most common pathogens to infect catheterized patients, coagulase-negative staphylococci, may not meet the previously published criteria of sepsis. It is hoped that the information contained here will lead to greater uniformity in the definitions used by the many investigators in this fascinating field.

Bacteremia↗
PubMed2000

Interaction between antibiotics and non-conventional antibiotics on bacteria.

The individual activity of antibiotics such as ampicillin, tetracycline, erythromycin and gentamicin in combination with compounds known to modify bacterial resistance to given antibiotics was studied using the checkerboard method. The combination of promethazine with either ampicillin, tetracycline or erythromycin or the combination of methylene blue and erythromycin produced significant synergistic activity against Escherichia coli. Verapamil, however, in combination with ampicillin reduced the activity of ampicillin against E. coli. Combinations of clomipramine with either tetracycline or erythromycin, promethazine and erythromycin or verapamil and ampicillin were synergistic against Staphylococcus epidermidis that was resistant to these antibiotics. The only synergy against Pseudomonas aeruginosa was shown by the combination of methylene blue and gentamicin.

Ampicillin↗
PubMed1999

Fusidic acid in vitro activity.

Fusidic acid is a narrow spectrum agent that acts to inhibit protein synthesis by inhibition of elongation factor G at the level of the ribosome. Because of high protein binding susceptibility testing in vitro is affected by the presence of blood or serum. In addition, there is a modest inoculum effect in vitro. A breakpoint of 1 or 2 mg/l is most widely used for defining resistance to systemic treatment with fusidic acid. Fusidic acid activity is principally directed at staphylococci, both Staphylococcus aureus and coagulate-negative species which are highly susceptible. It is also active against Gram-positive anaerobic activity, and shows in vitro activity against Neisseria spp., Bordetella pertussis and Moraxella catarrhalis. It has no activity against other aerobic Gram-negative species. Modest activity (MICs just above breakpoint values) is seen with Streptococcus and Enterococcus spp. as well as Gram-negative anaerobic bacteria. Fusidic acid is defined as bacteriostatic. For staphylococci MBC values are generally 8--32-fold that of the MIC. Interaction studies with other antibiotics give varying results depending on methodology. However, interaction with beta-lactams is generally indifferent, as it is with rifampicin, while aminoglycosides and macrolides appear to be synergistic and fluoroquinolones antagonistic. Fusidic acid appears to inhibit the function of neutrophils and T-lymphocytes at clinically achieved concentrations.

Anti-Bacterial Agents↗
PubMed2003

Effect of aryl ring fluorination on the antibacterial properties of C4 aryl-substituted N-methylthio beta-lactams.

4-Aryl-substituted N-thiolated beta-lactams are a new family of antibacterial agents possessing unique structure-activity profiles and a mode of action. Unlike traditional beta-lactam antibiotics, which require highly polar enzyme-binding groups, these lactams bear hydrophobic groups on their side chains. In this study, we examine the effect that increasing hydrophobicity, through fluorine substitution in the C(4) aryl ring, has on the antibacterial properties.

Anti-Bacterial Agents↗
PubMed1999

Synthesis and beta-lactamase inhibitory activity of new 6beta-cysteinesulfonamidopenicillanic acids.

New 6beta-cysteinesulfonamidopenicillanic acids and their sulfoxides were synthesized by sulfonylation of 6beta-aminopenicillanic acid or its (S)-sulfoxide with (R)-N-benzyloxycarbonylcysteinesulfonyl chloride ethyl ester (2a, 1b) and (R)-N-benzyloxycarbonylcysteinesulfonyl chloride benzyl ester (2a, 2b). The corresponding 6beta-cysteinesulfonamidopenicillanic acids sulfones 1c and 2c were prepared by oxidation of the sulfoxides 1b and 2b with potassium permanganate in aqueous medium. When combined with ampicillin some of the compounds reduced the minimal inhibitory concentrations of ampicillin against beta-lactamase producing strains.

Drug Interactions↗
PubMedDate not supplied

Triazole therapy for mucocutaneous candidiasis in HIV-infected patients.

Mucocutaneous candidiasis, such as oropharyngeal candidiasis, esophageal candidiasis, and vulvovaginal candidiasis, are common problems in patients with HIV infection. These conditions adversely affect patient quality of life and morbidity status. New oral triazole agents provide improved treatment options for patients with these and other opportunistic fungal infections; however, the development of resistance in some Candida species poses new challenges. This article provides an overview of the diagnosis of mucocutaneous candidiasis, current treatment modalities, concomitant drug interactions, common adverse drug reactions, and the emergence of fungal resistance, and it suggests nursing interventions to maximize patient benefits from antifungal therapy.

AIDS-Related Opportunistic Infections↗
PubMedDate not supplied

Overview of protease inhibitors.

PURPOSE: To provide a basic review of the four currently available protease inhibitors: saquinavir, ritonavir, indinavir, and nelfinavir. Included are sections on surrogate markers of HIV disease and resistance to protease inhibitor therapy, as well as dosing information, pharmacokinetics, studies, adverse effects, and drug interaction potential. DATA SOURCES: Conducted a review of published literature (MEDLINE), abstracts from national meetings and conferences, and product labeling and information available at the time of preparation through July 1997. STUDY SELECTION AND DATA EXTRACTION: Material was selected for inclusion based on relevance to objectives, publication in English, and presence of useful information for practicing pharmacists. DATA SYNTHESIS: Limited published information is currently available on the protease inhibitors, especially with regard to randomized, controlled, comparative trials and establishment of guidelines for direct therapy. Much of the available information relies heavily on product information and trials that are published only in abstract form. The evaluation of the protease inhibitors (with regard to place in therapy as well as resistance and toxicities) is an ongoing process. CONCLUSION: Protease inhibitors have changed opinions about the futility of the treatment of HIV disease. Protease inhibitors dramatically improve patients' surrogate markers and even show mortality benefits, especially when combined with additional antiretroviral agents. The optimism surrounding these new drugs is tempered by the toxicity profile, development of resistance, drug interaction profiles, and added costs to current regimens. Designing tolerable, effective regimens will require careful monitoring for compliance, adverse effects, and potential drug interactions.

Biomarkers↗