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E Loza

Publications and source records attributed to E Loza.

At least 37 records · Page 2Linked to original sources
PubMed1998

[Comparison of the microdilution method (PASCO), the Etest and disc-diffusion in streptococcus pneumoniae antibiotic susceptibility testing].

MIC values and inhibition zone diameters for penicillin, cefotaxime, and erythromycin where determined in 75 consecutive Streptococcus pneumoniae blood isolates by microdilution (PASCO), disc-diffusion and Etest. Using the Etest, 40% and 29.3% of the isolates showed low- or high-level resistance to penicillin and erythromycin respectively, whereas 9.3% were intermediate to cefotaxime. No high-level resistance to cefotaxime was found. No errors were found with the comparison of penicillin and cefotaxime results by microdilution and Etest, with just 2 (2.7%) and 3 (4%) minor errors appearing respectively. On the other hand, when comparing penicillin susceptibility results by disc-diffusion (1 mg oxacillin disc) and Etest, 6 (8%) major errors and 18 (24%) minor errors were found.

Anti-Bacterial Agents↗
PubMed1997

An outbreak of vampire bat-transmitted rabies in cattle in northeastern Mexico.

An outbreak of bovine rabies occurred on a ranch when cattle were bitten by vampire bats. Microscopic lesions showed a nonsuppurative encephalitis with intracytoplasmic inclusion bodies. Immunohistochemistry demonstrated viral antigen in the brain, and monoclonal antibodies identified a serotype 1 (vampire strain) of the rabies virus.

Animals↗
PubMed1996

Characterization of a nosocomial outbreak involving an epidemic plasmid encoding for TEM-27 in Salmonella enterica subspecies enterica serotype Othmarschen.

A ceftazidime-resistant Salmonella enterica subspecies enterica serotype Othmarschen strain, harboring the plasmid-mediated new extended-spectrum beta-lactamase TEM-27, was involved in a nosocomial outbreak (8 patients) at the Pediatric Cardiology Department of the Ramón y Cajal Hospital in Madrid. Genomic DNA polymorphism analysis, using an arbitrarily primed polymerase chain reaction, demonstrated the clonal nature of all Salmonella isolates. The plasmid encoding TEM-27 (pJMM1) was characterized by EcoRI, SacI, and BglI restriction. An identical restriction pattern was found in plasmid from all S. enterica strains. Possible in vivo intergeneric plasmid spread was suggested by the identification of an identical plasmid in Escherichia coli RYC5H and Enterobacter cloacae RYC39737 strains isolated during the outbreak. Results indicate that this outbreak involved dissemination of a single ceftazidime-resistant Salmonella strain and the spread of a single TEM-27-encoding plasmid among different Enterobacteriaceae.

Child, Preschool↗
PubMed1995

Right-sided endocarditis caused by Staphylococcus aureus in drug abusers.

A prospective, open, and randomized study of right-sided endocarditis caused by Staphylococcus aureus in drug abuse patients is reported. The following parenteral treatments were compared. Group A patients were treated with 2 g of cloxacillin every 4 h and 1.5 mg of gentamicin per kg of body weight every 8 h for 2 weeks. Group B patients were treated with teicoplanin at 10 mg/kg/12 h on the 1st to 3rd days, 6 mg/kg/12 h on the 4th to 7th days, and 7 mg/kg/24 h on the 8th days. Drug abusers with bacteremia caused by S. aureus and suggestive signs of endocarditis were included. Clinical failures were observed in one patient in group A and in four of six patients in group B. Three patients in group B developed breakthrough bacteremia with teicoplanin-susceptible strains on days +6, +14, and +19. Serum teicoplanin levels and serum bactericidal titers showed a decrease in the 2nd week, when dosages received were 7 mg/kg/day. In conclusion, in treatment of right-sided endocarditis caused by S. aureus in drug abusers with teicoplanin, the use of dosages of 7 mg/kg/day is not recommended even if patients have received dosages of 12 mg/kg/day during the 1st week.

Cloxacillin↗
PubMed1995

Pneumonia caused by Listeria monocytogenes.

Pneumonia due to Listeria monocytogenes is extremely uncommon. We report the case of an 87-year-old woman with no underlying immunosuppressive disease who presented with listerial pneumonia. Cutaneous anergy and a decrease in total lymphocyte count in this elderly woman could predispose her to listerial infection.

Adult↗
PubMed1994

In vitro selective antibiotic concentrations of beta-lactams for penicillin-resistant Streptococcus pneumoniae populations.

Therapeutic regimens containing beta-lactam antibiotics are selecting penicillin-resistant Streptococcus pneumoniae populations all over the world. The selective pressure after 4 h of exposure to different concentrations of amoxicillin, cefixime, cefuroxime, and cefotaxime for low-level or high-level penicillin-resistant S. pneumoniae was evaluated in an in vitro model with mixed populations with penicillin susceptibilities of 0.015, 0.5, 1, and 2 micrograms/ml. The antibiotic concentration selecting for low-level resistance strongly reduced the susceptible population. Increasing antibiotic concentrations tended to decrease the total proportion of penicillin-resistant bacteria because of reduced numbers of the low-level-resistant population. The antibiotic concentration selecting for high-level resistance produced fewer resistant populations, but most of the organisms selected represented high-level resistance. In general, amoxicillin was a good selector for the low-level-resistant population and a poor selector for high-level resistance; cefuroxime and cefotaxime were poor selectors for low-level resistance and better selectors than amoxicillin for high-level penicillin resistance. Cefixime was the best selector of low-level penicillin resistance. When only resistant populations were mixed, the strains with high-level resistance were selected even at low antibiotic concentrations. Determination of the effects of selective antibiotic concentrations on mixed cultures of bacteria expressing different antibiotic resistance levels may help researchers to understand the ecology and epidemiology of penicillin-resistant S. pneumoniae populations.

Amoxicillin↗
PubMed1993

Faster isolation of Brucella spp. from blood by isolator compared with BACTEC NR.

Brucella spp. was isolated from blood cultures in a mean time of 3.1 days (range, 2-5) in seven cases of human brucellosis processed with the Isolator lysis-centrifugation system. Simultaneous BACTEC NR blood cultures in the same patients were positive in six, with a mean detection time of 20.6 days (range, 17-29). These data suggest a higher speed of recovery of Brucella spp. from blood specimens with the lysis-centrifugation procedure compared with the BACTEC NR system.

Bacteriological Techniques↗
PubMed1992

Comparative in vitro activity of clarithromycin. Spanish Collaborative Group.

The activity in vitro of clarithromycin, a new macrolide, was compared to that of various antibiotics in tests using 3,880 clinical isolates. Clarithromycin was two times more active than erythromycin against Staphylococcus aureus, Enterococcus faecalis, Enterococcus faecium, streptococci of groups C, G and F, Brucella melitensis, Legionella pneumophila and Mycoplasma spp., 16 times more active against Ureaplasma urealyticum and 2 to 4 times less active against Campylobacter spp. In general, clarithromycin showed intrinsic activity 2 to 4 times higher than that of roxithromycin and 4 to 8 times higher than that of miocamycin. Cross-resistance was found between the macrolides. Clarithromycin was bactericidal against Streptococcus spp. and Haemophilus influenzae.

Clarithromycin↗
PubMed1992

In vitro activity of azithromycin and tetracycline against 358 clinical isolates of Brucella melitensis.

The in vitro activity of azithromycin against human pathogenic strains of Brucella melitensis was tested at three centres and compared to that of tetracycline, the standard antibiotic currently used for the treatment of human brucellosis. MIC determination was carried out. Tested concentration ranges for both azithromycin and tetracycline were between 0.03 and 16 micrograms/ml. Brucella melitensis biotype 1, strain M16 was employed as a control microorganism. A total of 358 Brucella melitensis strains from human blood cultures were tested. MIC90 (micrograms/ml) values ranged from 0.5 to 1.00 for azithromycin and were 0.25 for tetracycline. It was concluded that there was little difference in the sensitivity of pathogenic Brucella melitensis to azithromycin and tetracycline isolated from three different regions in Spain. These results encourage further investigations on the possible therapeutic role of azithromycin in brucellosis.

Azithromycin↗
PubMed1991

Prevention of anastomosis leakage: an artificial connective tissue.

Anastomosis leakage still causes considerable morbidity and mortality after digestive tract surgery. We report here our experience of the use of reconstituted connective tissue created from elastin, fibronectin and collagen in preventing anastomosis leakage and closing intestinal fistulas. In animal studies (56 rats), this connective tissue was used as a patch applied with fibrin sealant to the edges of a 1 cm diameter colonic defect. In a clinical evaluation, eight patients had an intestinal fistula closed by a simple sewn suture reinforced by a sealed patch and seven patients had a high risk anastomosis reinforced by a sealed patch, in most cases as an alternative to staged surgery. In animal studies, complete reconstitution of the three colonic layers was obtained without retraction and without inflammatory reaction within 40 days, while the patch was slowly resorbed. In clinical trials all 15 defects and anastomoses healed without complication. Three patients died from other causes and, at autopsy, the patch was found to have remained in place covering the suture line. If these results are confirmed by a prospective clinical trial, such biomaterial offers the possibility of reducing the occurrence of anastomosis leakage, especially in high risk circumstances.

Adult↗
PubMed1991

The incidence and beta-lactam resistance of Proteus vulgaris in hospital infections: the last decade.

During the period of 1980-1990, 581 Proteus vulgaris strains were obtained in a general hospital. They were considered as the significant isolate in 0.6% of soft tissue infections, 0.6% of urinary tract infections and in 0.2% of bacteremic episodes. Sixty-three percent of the 393 tested strains showed resistance to ampicillin, cefazolin and cefamandole or cefuroxime. About 7% were susceptible to all beta-lactam drugs, and showed a very low beta-lactamase activity and 5% of the strains showed a phenotype of resistance including ampicillin, carbenicillin-ticarcillin, cefazolin and cefamandole or cefuroxime, and presented increased chromosomal beta-lactamase activity. Cefotaxime-resistance was detected in 2% of the isolates which appeared in the period 1987-1990.

Ampicillin Resistance↗
PubMed1991

A review of antibiotic resistance patterns of Streptococcus pneumoniae in Europe.

Streptococcus pneumoniae no longer has predictable antibiotic susceptibility. There are two areas of high prevalence of resistance (over 25%) to beta-lactam antibiotics in the South-West and North-East of Europe. In Spain, a close relationship has been found between the yearly rate of aminopenicillin consumption and penicillin resistance. High level resistance (MIC greater than or equal to 1 mg/L) has developed against a previous background of low level resistance. The serotypes involved in penicillin resistance in Spain are widespread in other countries. Macrolide resistance is high in France (over 15%) and is also increasing in other countries. All these resistant isolates remain susceptible to the most recent fluoroquinolones, such as temafloxacin. Prospective surveillance, more rational use of antibiotics and a diversification of antibiotic use in respiratory tract infections may serve to limit the threat of antibiotic resistance in S. pneumoniae.

Drug Resistance, Microbial↗
PubMed1991

Malnutrition and body weight loss after biliopancreatic bypass in the rat.

In this study designed to investigate the nutritional state induced by biliopancreatic bypass in the rat, the pancreatico-biliary secretions were diverted via the duodenum and jejunum into the distal ileum, the remaining intestine being directly anastomosed to the stomach after antrectomy. Bypassed animals lost weight: it was only 56 percent of that of controls after 36 days and death by cachexia resulted within two months of the procedure. The reduced food intake (16 percent less than control) at the 36th postoperative day cannot by itself explain the weight loss, since pair-fed rat weights did not differ statistically from controls at 36 days. Protein-energy malabsorption occurred: drops in serum protein concentration (25 percent less than control), triglycerides (40 percent less) and total cholesterol (28 percent less) were recorded from the 12th postoperative day on. Biliopancreatic bypass may be an adequate procedure of treatment for morbid obesity simultaneously aggravated by metabolic disorders.

Analysis of Variance↗