[Microbiological research in acute diarrheal disease (ADD): the objectives, possibilities and limits].
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to D Buiuc.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The prosthodontics devices have a major role in healthy state or disease of periodontal structures. They may initiate or amplify tissues destruction when technical features or the used material are not the most appropriate. The aim of this study was to establish the influence of different materials on the evolution of chronic periodontal diseases by comparison to lesions associated with natural teeth. Lot of study was represented by 21 partial edentulous patients with periodontitis in both natural teeth and fixed prosthodontics. Periodontal pockets were sampled and then Gram stained smear and cultivation onto selective media (Schadler + 5% sheep blood + nalidixic acid + vancomycin) were done. The isolated bacteria were identified by standard methods. We observed quantitative and qualitative differences between studied patients according to the material used for making the fixed prosthodontics.
The accumulation of dental plaque on fixed prostheses made of various biomaterials is influenced by the roughness of the surface. For the investigation of this aspects it was necessary of a method rapid, facile and cheaper in comparison with bacterial culturing and identification which is laborious and expansive. In this study we followed the accumulation of dental plaque on biomaterials like chrome-cobalt and gaudent polished and unpolished, at different periods of time (3 and 14 days). We observed that after 3 days the aspect is predominant coccoid and after 14 days is predominant bacillary. On unpolished crowns the width of dental plaque is greater and on gaudent crowns the plaque is structural organised around of filamentous organisms.
Explore the source record for details and available documents.
To evaluate the resistance trends for Escherichia coli isolates during 1993-1999 period in Eastern Romania to: ampicillin (A), ampicillin-sulbactam (A/S), ceftazidime (CAZ), cefotaxime (CTA), ceftriaxone (CRO), aztreonam (AZT), ofloxacin (OF), ciprofloxacin (CIP), tetracycline (T) and chloramphenicol (C). We tested 2012 clinical isolates obtained from faeces and urine. MICs were determined by a dilution method in Mueller-Hinton agar (NCCLS guidelines). Resistance rates were analyzed using the NCCLS breakpoints for the fully susceptible category (moderately susceptible strains were classified as resistant). No significant differences were observed in susceptibility of E. coli to ampicillin and ampicillin/sulbactam in the last years. The high percentage of resistant isolates was observed in 1995 for ampicillin (89.7%). Higher incidences of resistance were detected for A, A/S, T; the addition of sulbactam restored A susceptibility only for a small percent. CAZ, CTA, CRO, AZT, OF and CIP resistance among E. coli isolates was progressively increased in the last period.
The aim of this study was to investigate the activity of new quinolones against clinical isolates of E. coli, obtained from hospitalized patients between 1999-2000, in Eastern Romania. We tested 411 strains, isolated from urine. Susceptibility of the isolates to norfloxacin, ciprofloxacin, nalidixic acid and ofloxacin was performed using the dilution method in Mueller-Hinton agar. Susceptibility was reported using the NCCLS breakpoints. Minimum inhibitory concentration (MIC) was defined as the lowest concentration of antimicrobials that inhibited growth of the bacteria. Based on MIC breakpoints for defining susceptibility, between 12.4-13.7% of isolates were resistant to modern quinolones. Resistance to nalidixic acid significantly diminished the clinical use: level of the susceptible strains was only 12.9%.
The use of organomercurials in liquid detergents and disinfectants promoted resistance to mercury among bacteria. Dental amalgam and industries using mercury are the main source of human exposure to mercury vapor. Release of mercury from dental amalgam contributes to the enrichment of the intestinal flora with mercury resistance plasmids which may be associated with antibiotic resistance. The aim of our study was to evaluate the frequency of E. coli strains resistant to mercury and other antimicrobial agents currently used in therapy. The bacterial mercury and ampicillin, cephalexin, cefotaxime, gentamicin, tetracycline and chloramphenicol resistance was tested against 363 E. coli strains obtained from faeces and urine between 1999-2000. According to the guidelines suggested by NCCLS (1998), minimum inhibitory concentrations (MICs) were determined on Mueller-Hinton agar, using the dilution technique with an inoculum of about 10(5) CFU. The MICs were read after 18 h incubation at 37 degrees C as the lowest concentration that inhibited the development of visible growth. Plasmids in enterobacteria may carry genes encoding resistance to both mercury and antibiotics. Among the tested E. coli strains, mercury resistance rose to 29.2%. Mercury resistance in E. coli is significantly linked to multiresistance to antimicrobial agents. Between 91.5-23.6 of mercury chloride resistant isolates were also resistant to the tested antibiotics. The increased use of non antibiotic antimicrobial agents is a possible selection factor for antibiotic-resistant strains in clinical and domestic environments.
Anaerobes are often involved in human pathology, including oral infections. The therapy of anaerobic infection requires certain antibiotics such as: metronidazole, tetracycline or amoxicillin. But the incidence of resistant strains among anaerobes is continuously increasing and it is necessary to find some new agents effective against these bacteria. The aim of our study was to establish the bactericidal activity of two new quinolones against 14 strains of gram-negative anaerobic bacilli. The MIC of tested strains was first detected and then time-kill kinetics was determined by using Miles and Misra methodology. Ciprofloxacin was used as standard-quinolone. The results show that trovafloxacin and moxifloxacin have good activity against anaerobes, better than that of ciprofloxacin. Bactericidal curves suggest a rapid action of moxifloxacin (within the first 4 hours), but a prolonged cidal activity for trovafloxacin (24 hours). For both agents, the antimicrobial effect is concentration-dependent. As previous studies suggest, the new quinolones have good activity against both aerobic and anaerobic bacteria so they are useful in the treatment of mixed infections (common feature of anaerobic infections).
The aim of this study was to evaluate the in vitro activity of cefotaxime, ceftriaxone, ceftazidime, ceftibuten and aztreonam against the clinical isolates of Enterobacteriaceae. MICROORGANISMS: A total of 973 enterobacteria isolated from clinical material (urine and faeces) were tested. Strains were collected during 1996-1998 period, in some centers of Eastern Romania. SENSITIVITY STUDY: MICs were performed using the agar dilution method following standardized techniques (NCCLS, 1994). Stock solutions of antibacterial agents were prepared from their respective powder forms, in concentrations ranging from 0.03 to 128 mg/ml. Our results show a good activity of the tested antimicrobials on Escherichia coli, Shigella spp and Klebsiella spp tested, and reveal a particular behaviour for Salmonella spp, characterized by a heterogenous susceptibility. In conclusion, cefotaxime, ceftriaxone, ceftazidime, ceftibuten and aztreonam were active at low concentrations against tested isolates. Against Salmonella spp, these agents were less active: percent of resistant strains by beta-lactamase production was significant.
Extended-spectrum beta-lactamases (ESBL) cause resistance to ceftazidime, ceftriaxone, cefotaxime and other cephalosporins. The ESBL enzymes are most often derivatives of beta-lactamases from the TEM or SHV group. The aim of our work was to study ESBL production by 35 ceftazidime-resistant strains. We selected these strains among 335 Enterobacteriaceae, isolated in Eastern Romania from healthy carriers and patients, between january-june 1999. To identify the studied strains we used API 20E and API 32E. The ESBL production was established by using both double disk synergy test (DDT) and EXPERT computer program of miniAPI (Bio Merieux). We revealed ESBL production in 26 strains when EXPERT program was used and only 23 when DDT was used. Our results suggest that miniAPI is a better method to study ESBL production than DDT.
The conditions for obtaining and the properties of some new diazabicyclic compounds is the new step in our investigation on the benzocynoline derivatives. The structure of the new compounds was confirmed by elementary (C, H, N) and spectral analyses. The antimicrobial tests evidenced that part of the newly synthetized compounds have a good antifungal action.