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PubMedDate not supplied

[Rapid method of testing microbiol sensitivity to antibiotics].

The conventional technique for determining the sensitivity of bacteria to antibiotics is slow and a more rapid method becomes mandatory. The authors tested microbial sensitivity to antibiotics by measuring turbidity of the cultures in fluid medium. The method offers an orientation in the choice of an elective antibiotic within at most 4 hours.

Anti-Bacterial Agents↗
PubMedDate not supplied

[Bacteriologic examination of gallbladder contents].

INTRODUCTION: Acute calculous (obstructive) cholecystitis develops as a consequence of cystic obstruction and obstruction of bile flow into choledochus. Most often it is a result of impacted gallstones in Hartman's pouch or the cystic duct. Their direct pressure on gallbladder mucosa causes ischemia, necrosis and ulceration with consequential wall edema and obstructed venous flow. This mechanism is further increasing and spreading the inflammatory process. Ulcerations may be that extensive, that mucosa is highly recognizable on the microscopic preparation. Leukocyte infiltration of all segments occurs. Results of necrosis are as follows: perforation with pericholecystic abscess formation, fistulization or biliary peritonitis. AIM: The aim of this investigation was to use microbial sensitivity tests in order to establish possibilities of antibiotic therapy in patients with acute cholecystitis. MATERIAL AND METHODS: Using random sampling a total of 240 patients with acute cholecystitis were included in the investigation. They were all treated at the Clinic of Abdominal and Endocrine Surgery of the Clinical Center Novi Sad in the period 1997-1999. All patients underwent bacteriological examination and were coherent in regard to sex and age. Microbial sensitivity tests analyzed two groups of bacteria: Group I: Escherichia coli, Klebsiella and Staphylococcus and Group II: other isolated bacteria (Citrobacter, Enterobacter, Enterococcus, Proteus, Pseudomonas, Serratia and Streptococcus). RESULTS: In our material Escherichia coli was isolated in most patients--32 (55.17%), Klebsiella and Staphylococcus in 6 (10.34%) patients and Streptococcus in 4 (6.90%), whereas other bacteria were infrequent (Citrobacter and Serratia in 3.45%, Enterobacter, Proteus and Pseudomonas in 1.75%). Thus, E. coli, Klebsiella and Staphylococcus were established in 75.85% of bacteriologic findings, and all the rest in 24.15%. Assessment regarding premedication with antibiotics started with an assumption that cholecystitis was caused by one of the bacteria isolated in 75% of cases. That is why antibiotics should be given prior to surgery, primarily those to which these bacteria are susceptible in more than 95% of cases. CONCLUSIONS: E. coli, Klebsiella and Staphylococcus participate with 75.85% of all bacteriologic findings, whereas all the others make 24.15%; Amikacin, Cefalexin, Ceftriaxone, Ofloxacin and Pefloxacin are recommended in premedication; considering the fact that new generation antibiotics have not been tested yet, they were not taken into consideration for this study.

Acute Disease↗
PubMed1998

Antibiotics for the preservation of koala (Phascolarctos cinereus) semen.

AIM: To determine the normal microbial flora of the koala ejaculate and prepuce in order to select appropriate antibiotics for addition into diluents designed for the preservation of semen. PROCEDURE: Bacteriological samples of the koala prepuce (n = 12) and ejaculate (n = 20) were submitted for microbial culture and sensitivity testing. Microbial flora of ejaculates collected by electroejaculation and artificial vagina were compared. The effects of varying concentrations of penicillin G and gentamicin on sperm motility and on the growth of bacteria in diluted semen stored at room temperature and 16 degrees C over a 24 h period were investigated. RESULTS: A range of bacteria was isolated from the koala prepuce and ejaculate. The predominant organisms in semen collected by electroejaculation and artificial vagina were Corynebacterium spp, none of which could be assigned to any recognised species. The addition of penicillin G and gentamicin to a PBS-based diluent at dose rates of 1000 to 2000 IU/mL and 100 to 200 micrograms/mL respectively, resulted in no adverse effect on sperm motility over a 24 h incubation period. Penicillin G (1000 IU/mL) and gentamicin (100 micrograms/mL) prevented growth of bacterial contaminants in diluted koala semen. CONCLUSION: By controlling the growth of bacteria in extended koala semen, penicillin G and gentamicin are likely to lengthen the period by which spermatozoa can be stored at 16 degrees C and reduce the possibility of disease transmission during artificial insemination procedures.

Animals↗
PubMedDate not supplied

In vitro testing of antibiotics.

To enhance knowledge in the area of in vitro testing of antibiotics and to understand the limitations of available methods for susceptibility testing, we conducted a MEDLINE literature search in the English language to accumulate relevant articles. Headings searched included microbial sensitivity tests; Kirby-Bauer; laboratory tests; antiinfective agents; antibiotics, combined; microbiological techniques; blood bactericidal assay; and pharmacology, clinical. The management of patients with serious life-threatening infections can be complicated by recent changes in organism nomenclature, newly marketed antibiotics, and new isolation and sensitivity testing methods. With the addition of formulary constraints, many problems and controversies arise regarding interpretation of antibiotic sensitivity results. Comprehensive care for infected patients requires assessment of current antibiotic therapy and options for alternative therapy. By applying pharmacodynamic and pharmacokinetic knowledge to known limits of in vitro testing results, the clinician is able to select the most efficient antibiotic or antibiotic combination.

Anti-Bacterial Agents↗
PubMed2005

[Dynamic analysis of drug resistance of Pseudomonas aeruginosa in laboratory and clinical two-drug regimen].

OBJECTIVE: To analyze drug resistance status of Pseudomonas aeruginosa in the two-drug regimens in laboratory and clinical settings for more appropriate application of antibiotics. METHODS: The laboratory data of drug resistance rate of Pseudomonas aeruginosa identified with Biomerieux Vitek 32 system were collected. The clinical two-drug regimen data corresponding to anti-microbial sensitivity test were investigated, and the resistance rate of the clinical two-drug regimen was analyzed statistically. RESULTS: The isolation rate of Pseudomonas aeruginosa with multi-drug resistance increased steadily in recent years, and the resistance rate to 6 widely used antibiotics increased by over 20%. Two Pseudomonas aeruginosa strains resistant to all the 6 drugs were identified in January 2004, and till June 2005, totally 18 panresistant strains had been isolated with dramatic increases in MIC value. In the clinical two-drug regimen, sulbactam/amikacin, sulbactam/ciprofloxacin, tazobactam/amikacin, and imipenem/amikacin still had low resistant rates. CONCLUSIONS: Multi-drug resistance of Pseudomonas aeruginosa to the antibiotics is a serious problem. A two-drug regimen based on anti-microbial susceptibility test should be chosen.

Amikacin↗
PubMed2002

Antibiotic sensitivities of common bacterial pathogens in urinary tract infections at Gondar Hospital, Ethiopia.

OBJECTIVE: To determine the prevalence and sensitivity trends of urinary bacterial isolates. DESIGN: A cross-sectional study. SETTING: Gondar College of Medical Sciences (GCMS) Teaching and Referral Hospital, north west Ethiopia. SUBJECTS AND METHODS: Four hundred and twenty urine specimens from 70 in-patient and 350 out-patient cases were studied by quantitative culture method and anti-microbial sensitivity test was done by disc diffusion technique. RESULTS: One hundred and seventy two pathogenic organisms were isolated from 166 patients; the isolation rate was 39.5 %. Among the isolates E. coli, S. aureus, Klebsiella species, coagulase negative Staphylococcus species and Citrobacter species were common accounting for 46.0%, 18.0%, 10.0%, 8.0% and 6.0%, respectively. Of the total isolates 71.5% were Gram negatives. Sensitivity tested against ten antibiotics showed that resistance was common, and the effectiveness of tetracycline, ampicillin, co-trimoxazole, chloramphenicol and penicillin was under 50.0%. The resistance rate was 71.5%, 62.2%, and 62.2%, 54.7% and 40.8%, respectively. Polymixin B, cefoxitin, gentamycin and erythromycin controlled over 76.0% of the common infective agents. Ciprofloxacin did control 98.3% of the organisms. CONCLUSION: Resistance was found to be very high to the commonly used antibiotics. The sensitivity rate for the recently introduced ciprofloxacin was above 98%. Therefore, this antibiotic may be used for empirical therapy of urinary tract infection (UTI) when culture and sensitivity testing is impossible. Strict control on the use of antibiotics and appropriate measures against over the counter availability and self-medication is recommended.

Adolescent↗
PubMed2004

Control of microbial contamination during surgical harvest of pig renal xenografts.

The pig has been identified as the most likely source of xenograft material for clinical use and studies are ongoing to overcome the immunological hurdles of pig-to-human transplantation. Attention is now being focussed on identifying and reducing the potential microbiological hazards associated with this technique. Studies have primarily addressed issues surrounding the production and health monitoring of xenograft source pigs and none have so far specifically evaluated the possible risks of microbial contamination during xenograft harvest. In this report, we evaluate the possible routes for contamination of a pig kidney xenograft during organ harvest and describe approaches to the control of these hazards, including the novel use of a custom designed airtight surgical canopy. A standard procedure for microbiological monitoring during xenograft harvest was devised and evaluated. This allowed the rapid identification and anti-microbial sensitivity testing of any isolated organisms. This would enable an early and appropriate pre-emptive treatment of infection because of transmission of pig micro-organisms.

Animals↗
PubMed2005

Outpatient prescription of oral antibiotics in a training hospital in Turkey: trends in the last decade.

AIM: The aim was to evaluate the changing trends in outpatient prescription of oral antibiotic forms at a Training Hospital in the last decade. MATERIAL AND METHOD: All the outpatient prescriptions during April and May 2004 were evaluated. The diagnosis, the department of the prescriber, the count and generic name of each prescribed antibiotic were all noted. RESULTS: Of the 33,491 outpatient prescripitions, 14.9% included antibiotic (n=5004). The pediatric clinics (26.4%), Ear, Nose and Throat department (13.7%), and the department of Gyneacology and Obstetrics (10.8%) were the leading departments in antibiotic prescriptions. Upper respiratory tract infections (45.4%), urinary tract infection (11.4%) and lower respiratory tract infections (4.2%) shared the first lines of diagnosis stated. Of the antibiotic prescriptions, 96.3% included oral forms. Co-amoxiclav (26.4%), quinolones (11.7%) and cephalosporins (16.5%) were the most frequently prescribed antibiotics. Percent of antibiotic prescriptions based on microbial sensitivity test results was 7.1%. CONCLUSION: Compared with the results of the study carried out 11 years ago; though co-amoxiclav is still the most frequently prescribed antibiotic, many other changes have been observed in antibiotic prescription attitudes.

Anti-Bacterial Agents↗
PubMed1987

[Epidemiologic studies of the microbial colonization of severely burned patients].

Bacteria isolated between 1/1/1983 and 12/31/1984 from the burns of 122 patients in a burns unit at the Ruhr-Universität Bochum were studied. Grampositive bacteria were predominant in colonizing the burn wounds (62.5% of all strains isolated). In the patients with more than 40% of total body surface area (TBSA) burn, isolation of Staph aureus was most frequent. The exogenous colonization rate with Staph. aureus was 86%. Coagulase negative Staphylococci were identified in 89.6% of all patients (71.4% of the patients with more than 40% TBSA burn). There was a constant decline in detecting Pseudomonas aeruginosa from the second half of 1983. Microbial sensitivity testing was performed in 834 cases. Gramnegative strains of bacteria resistant to Ampicillin, Mezlocillin, Piperacillin and Ticarcillin were found in 10 up to 97% of the tested strains. Acinetobacter calcoaceticus var. antitratus and Enterobacter cloacae usually displayed a wide resistant pattern. Some strains were resistant as to 16 antibiotics. The incidence of multiresistant Staph. aureus was studied. The time course of multiresistance was paralleled by the incidence of a 6-fold resistance to Benzylpenicillin, Oxacillin, Tetracyclin(T), Gentamycin(G), Erythromycin(E), and Sulfadiacin(S). The probability of simultaneous resistance to 2 of the 4 antibiotics (T, G, E, S) ranged between 0.7 and 0.98. 98 out of 336 Staph. aureus isolates showed a simultaneous resistance to T, G, E and S (29%).

Adolescent↗
PubMed2006

Phenotypic heterogeneity can enhance rare-cell survival in 'stress-sensitive' yeast populations.

Individual cells within isogenic microbial cultures exhibit phenotypic heterogeneity, an issue that is attracting intense interest. Heterogeneity could confer benefits, in generating variant subpopulations that may be better equipped to persist during perturbation. We tested this hypothesis by comparing the survival of wild-type Saccharomyces cerevisiae with that of mutants which are considered stress-sensitive but which, we demonstrate, also have increased heterogeneity. The mutants (e.g. vma3, ctr1, sod1) exhibited the anticipated sensitivities to intermediate doses of nickel, copper, alkaline pH, menadione or paraquat. However, enhanced heterogeneity meant that the resistances of individual mutant cells spanned a broad range, and at high stress occasional-cell survival in most of these populations overtook that of the wild type. Green fluorescent protein (GFP) reporter studies showed that this heterogeneity-dependent advantage was not related to perturbation of buffered gene expression. Deletion strain screens combined with other approaches revealed that vacuolar alkalinization resulting from loss of Vma-dependent vacuolar H(+)-ATPase activity was not the cause of vma mutants' net stress sensitivities. An alternative Vma-dependent resistance mechanism was found to suppress an influence of variable vacuolar pH on the metal resistances of individual wild-type cells. In addition to revealing new mechanisms of heterogeneity generation, the results demonstrate experimentally a benefit under adverse conditions that arises specifically from heterogeneity, and in populations conventionally considered to be disadvantaged.

Acids↗
PubMed1996

Phenotypes of dnaA mutants of Escherichia coli sensitive to phenothiazine derivatives.

The activation of DnaA protein by cardiolipin is inhibited by fluphenazine in vitro. We therefore examined the sensitivity of temperature-sensitive dnaA mutants of Escherichia coli to fluphenazine and other phenothiazine derivatives. Among the eight dnaA mutants tested, dnaA5, dnaA46 dnaA602, and dnaA604, mutants with mutations in the putative ATP binding site of DnaA protein, showed higher sensitivities to phenothiazine derivatives than did the wild-type strain. The dnaA508 and dnaA167 mutants, which have mutations in the N-terminal region of DnaA protein, also showed higher sensitivities to phenothiazine derivatives. On the other hand, the dnaA204 and dnaA205 mutants, with lesions in the C-terminal region of the DnaA protein, showed the same sensitivity to phenothiazine derivatives as the wild-type strain. Complementation analysis with a plasmid containing the wild-type dnaA gene and phage P1-mediated transduction confirmed that dnaA mutations are responsible for these sensitivity phenotypes.

Bacterial Proteins↗
PubMed2000

The rpoN gene of Enterococcus faecalis directs sensitivity to subclass IIa bacteriocins.

The final sigma 54 factor has been previously described to be involved in Listeria monocytogenes sensitivity to mesentericin Y105, a subclass IIa bacteriocin. Here, we identified the rpoN gene, encoding final sigma 54, of Enterococcus faecalis JH2-2 and showed that its interruption leads to E. faecalis resistance to different subclass IIa bacteriocins. Moreover, this rpoN mutant remained sensitive to nisin, a class I bacteriocin, suggesting that final sigma 54 is especially involved in sensitivity to subclass IIa bacteriocins.

Bacteriocins↗