Search PubMed⌕ Search

Biomedical subjects

M Gobernado

Publications and source records attributed to M Gobernado.

At least 91 records · Page 5Linked to original sources

[Ampicillin-sulbactam activity against respiratory isolates of Haemophilus influenzae].

A study was conducted on the in vitro activity of ampicillin/sulbactam against 100 respiratory strains of Haemophilus influenzae (45 betalactamase positive and 55 betalactamase negative strains) simultaneously isolated during 1997 in 6 Spanish hospitals: Hospital Clínico San Carlos (Madrid), Hospital de Cruces de Basurto (Bilbao), Hospital La Fe (Valencia), Hospital Virgen Macarena (Seville), Hospital de Bellvitge (Barcelona) and Hospital Clínico Universitario (Salamanca). It was studied in comparison to amoxicillin, amoxicillin/clavulanic acid, cefuroxime, clarithromycin and ciprofloxacin. The MIC breakpoints used for the interpretation of data were those published by the National Committee for Clinical Laboratory Standards in 1997. All of the strains tested were susceptible to ampicillin/sulbactam, amoxicillin/clavulanic acid, cefuroxime and ciprofloxacin. The rate of resistance to clarithromycin was 55.5% for betalactamase positive strains and 38. 2% for betalactamase negative strains. A total of 23.6% of the betalactamase negative strains were resistant or showed intermediate susceptibility to amoxicillin but were susceptible to betalactam/betalactamase inhibitor combinations and cefuroxime.

Amoxicillin↗

In vitro activity of fosfomycin trometamol against pathogens from urinary tract infections: a Spanish multicenter study.

The in-vitro susceptibilities of a total of 1371 urinary tract pathogens to fosfomycin trometamol were determined. According to the NCCLS breakpoints, Enterobacteriaceae and gram-positive microorganisms were, in general, very sensitive to this antimicrobial. More than 90.0% of the Escherichia coli and Citrobacter spp. and more than 70.0% of the Klebsiella pneumoniae, K. oxytoca, Enterobacter spp., Proteus mirabilis, Staphylococcus aureus, coagulase-negative staphylococci and Enterococcus spp. strains tested were susceptible to fosfomycin trometamol. However, Pseudomonas aeruginosa and Acinetobacter spp. strains were more resistant. In general, recent clinical isolates from urinary tract infections (UTIs) in both community and hospital were also very sensitive (> 80.0%) to fosfomycin, its activity being higher than that of the rest of the antimicrobials commonly used for therapy of uncomplicated UTIs. More than 75.0% of the most frequently isolated pathogens from UTIs, except for P. aeruginosa (31.8%) and Acinetobacter spp. (11.1%), were susceptible to fosfomycin trometamol. The results obtained in this study, together with the infrequency of side effects and its pharmacokinetic properties, indicate that fosfomycin trometamol may be a useful alternative for single-dose therapy of uncomplicated UTIs.

Anti-Bacterial Agents↗

Pulmonary infection with Nocardia species: a report of 10 cases and review.

Pulmonary nocardiosis (PN) is an infrequent and severe infection due to Nocardia spp., microorganisms that may behave both as opportunists and as primary pathogens. The aim of this study and review was to evaluate the clinical features, evolution and prognostic factors of PN. The study group comprised 10 consecutive patients with pulmonary nocardiosis acquired in a community setting, diagnosed and followed in a tertiary teaching hospital. Chronic obstructive pulmonary disease (COPD), neoplastic disease and human immunodeficiency virus (HIV) infection were the most frequent predisposing factors. Four patients were receiving corticosteroid treatment. Clinical course was chronic and diagnosis was delayed 3 weeks or more in seven of the patients. Lobar or multilobar condensation was the most frequent radiographic pattern. Antimicrobial susceptibility testing showed: 100% sensitivity for amikacin; 83% for imipenem; 71% for cefotaxime; and 71% for trimethoprim-sulphamethoxazole. The disease remained localized in the lung in five cases, with a trend toward chronicity in one with bronchiectasis. In the other five, the disease disseminated, affecting subcutaneous tissue, the central nervous system and the kidney. Three patients died, one with disseminated disease and two who were receiving corticosteroid therapy. The following conclusions were reached: 1) pulmonary nocardiosis is difficult to diagnose, diagnosis is frequently delayed and a high level of suspicion is, thus, required in patients with underlying diseases or chronic corticosteroid therapy; 2) there is frequent dissemination and high mortality; and 3) antimicrobial combinations with proven synergy, such as imipenem and amikacin, are recommended for initial therapy.

Adult↗

Laparoscopy and septic dissemination caused by perioperative perforation of the occluded small bowel: an experimental study.

Based on the observation of septic shock and severe respiratory impairment in two patients subjected to laparoscopic surgery for small bowel occlusion, an experimental study was carried out in rabbits to evaluate the effect of intra-abdominal CO2 hyperpressure on massive bacterial spread. Increased bacterial access to the blood was observed as a result of the mechanical effect of the hyperpressure associated with the highly septic contents of the occluded bowel. The important risk of bacterial dissemination following accidental peroperative perforation requires extreme caution in the laparoscopic management of late occlusions of the small intestine.

Animals↗

Treatment of chronic hepatitis C with interferon-alpha. Clinical histological and virological implications.

OBJECTIVE: to identify pretreatment predictive factors of long-term biochemical and virological response to interferon-alpha in chronic hepatitis C and to determine the effects of a second course of interferon-alpha in patients who responded but relapsed after interferon withdrawal. DESIGN: retrospective analysis. SETTING: outpatient liver clinic of a tertiary hospital in Spain. PATIENTS: 112 patients with chronic hepatitis C were treated with recombinant interferon-alpha (3 MU three times a week for 6 months). Twenty-four patients who responded but relapsed after interferon withdrawal were treated with a second course of interferon (3 MU three times a week for 12 months). RESULTS: seventy-two patients were non-responders (64%), 11 patients had a sustained response (10%) and 29 patients responded but relapsed after interferon withdrawal (26%). Five (25%) of the 24 patients who relapsed and were treated with a second course of interferon experienced a sustained response (mean follow-up: 10 months). By multivariate analysis, four pretreatment variables were found to be predictive of a complete response: age < 40 years (p = 0.0004), history of IVDA (p = 0.001), low serum levels (p = 0.013), and genotype 3 (p = 0.01). Two variables were found to be predictive of a sustained response: short duration of HCV infection (p = 0.09) and genotype 3 (p = 0.01). Sustained responders appeared to have lower HCV-RNA levels than those with complete response who relapsed and non-responders. HCV viremia levels were not associated with the severity of liver histology, duration of disease or the source of hepatitis. CONCLUSIONS: in the present study a low sustained response rate was observed using a standard interferon-alpha regimen (3 MU three times a week for 6 months). The sustained response rate increased slightly with a second course of interferon-alpha (3 MU three times a week for 12 months) in patients with a complete response who relapsed after interferon withdrawal. Sustained response is related to viral genotype and duration of HCV infection.

Adolescent↗

Disseminated Blastoschizomyces capitatus infection in acute myeloblastic leukaemia. Report of three cases.

Three new cases of Blastoschizomyces capitatus infection occurring in neutropenic patients with acute myeloblastic leukaemia are reported. B. capitatus was isolated from blood cultures in all patients. All three patients were treated with amphotericin B, but only one was cured from the infection. Our study confirms the emergence of B. capitatus as an opportunistic agent of disseminated fungal infection in leukaemic patients.

Adult↗

Immunohistochemical expression of Epstein-Barr virus-encoded latent membrane protein (LMP-1) in paraffin sections of EBV-associated nasopharyngeal carcinoma in Spanish patients.

Nasopharyngeal carcinoma (NPC) paraffin samples, from Spanish patients, of distinct histological types, including squamous cell carcinoma (10 cases), nonkeratinising carcinoma (12 cases) and undifferentiated carcinoma (29 cases) were analysed for Epstein-Barr virus (EBV) detection and EBV-encoded latent membrane protein (LMP-1) expression using a sensitive nested-polymerase chain reaction with four oligonucleotide primers specific for EBV genome (EB-1, 2, 3, 4) and immunohistochemistry by means of CS1-4 pool monoclonal antibody. EBV genome was detected regardless of histological type in 100% of samples with sufficient DNA quality to permit viral diagnosis (50 out of 51 cases), supporting the previous view that all types of NPC are variants of an EBV-associated malignancy. However LMP-1, an EBV-encoded oncogenic protein, was detected in 40 out of 51 samples (78.4%) and LMP-1 immunohistochemical expression was not apparently influenced by histological type, primary or metastatic site, clinical stage, age or sex. This high percentage of detection of LMP-1 in our cases supports a role for EBV in the pathogenesis of different types of NPC, but the lack of constant expression of LMP-1 in NPC remains unclear and various reasons are postulated to explain the absence of this oncogenic protein in some EBV-associated NPCs.

Adolescent↗

Genome detection in liver and peripheral blood mononuclear cells: predictor factors of sustained response in patients with chronic hepatitis C.

BACKGROUND: In chronic hepatitis C, relapses of liver disease occur in as many as 50% of patients responding to interferon (IFN) therapy. Although the presence of serum hepatitis C virus (HCV) RNA at the end of therapy predicts a relapse, its absence is not a reliable indicator of cure. In this study we have determined whether responders to IFN (normalization of liver chemistry and clearance of serum HCV-RNA) harbour HCV-RNA in the liver and peripheral blood mononuclear cells (PBMCs), and whether finding the genome at these sites has prognostic significance. METHODS: After the conclusion of therapy, we tested for HCV-RNA in the liver of all the patients (anti-HCV-positive): 16 complete responders with normalization of liver chemistry and clearance of serum HCV-RNA and five non-responders. In 13 of the 16 complete responders we also tested for HCV-RNA in PBMCs. Patients were followed up for 9 months. RESULTS: Liver HCV-RNA was detected in each of the five non-responders and in four of the 16 complete responders (25%). The viral genome was detected in the PBMCs of six complete responders (46%). During follow-up a relapse of hepatitis C occurred in the 10 complete responders with liver or PBMC HCV-RNA but in only one (16%) of the six complete responders without HCV-RNA in liver or PBMCs. CONCLUSION: Reliable information on the prognosis of chronic hepatitis C responders can only be obtained by testing for HCV-RNA in serum, liver and PBMCs at the end of therapy. Patients with HCV-RNA at any of these sites stand a high risk of disease relapse. The risk is low but not abolished in patients without detectable HCV-RNA.

Aged↗

Intraphagocytic killing of gram-positive bacteria by ciprofloxacin.

The intraphagocytic killing of Staphylococcus aureus, Streptococcus pyogenes, and Corynebacterium group D2 by ciprofloxacin (0.1, 1 and 5 mg/L) within human neutrophils was determined. The organisms showed different susceptibility to neutrophil killing mechanisms. The neutrophils with intact and impaired (by phenylbutazone treatment) O2-dependent killing mechanisms were studied. The minimum concentrations of ciprofloxacin to kill 90% of phagocytosed bacteria within untreated neutrophils after 2 h were 1 mg/L for S. aureus and Corynebacterium group D2, and 0.1 mg/L for S. pyogenes. In contrast, exposure for 3 h was required to achieve similar cidal effects within phenylbutazone treated neutrophils. Synergic interaction between ciprofloxacin and the O2-dependent mechanisms of phagocytes was found. The reactive oxygen metabolites produced in the respiratory burst did not affect the intraphagocytic activity of ciprofloxacin. Phenylbutazone treatment of phagocytes would be a good experimental model to study intraphagocytic killing by drugs in situations where the oxidative mechanisms of neutrophils are impaired (for example AIDS and chronic granulomatous disease).

Cell Death↗

Intraphagocytic bioactivity of lomefloxacin against Pseudomonas aeruginosa.

The kinetics of extracellular bactericidal activity and the intraphagocytic bioactivity of lomefloxacin at concentrations 2 mg/L (1/2 x MIC), 4 mg/L (MIC) and 8 mg/L (2 x MIC) against Pseudomonas aeruginosa were measured, the first in 40% human serum and the second in polymorphonuclear leucocytes (PMNLs), by the colony-counting method. The PMNLs were treated with phenylbutazone to prevent them killing the bacteria during the ingestion period. The kinetics of extracellular killing were biphasic with an initial rapid phase lasting 30 min when lomefloxacin was used at concentrations equal to the MIC and 2 x MIC, during which a decrease of 3 log of cfu/mL occurred. Lomefloxacin showed intraphagocytic activity at the three concentrations assayed. With non-treated PMNLs the percentages of intraphagocytic killing after 30 min of incubation were 93.5, 91.3 and 95.5% with 2, 4 and 8 mg/L, respectively, and 79.8, 65.0 and 93.3% for the same lomefloxacin concentrations with phenylbutazone-treated PMNLs, suggesting a synergic interaction between the antibacterial activity of PMNLs and lomefloxacin.

Anti-Infective Agents↗

In vitro activity of sparfloxacin compared with those of five other quinolones.

The in vitro activity of sparfloxacin, a new difluorinated quinolone, was evaluated against 857 gram-positive and gram-negative clinical isolates and compared with those of ciprofloxacin, norfloxacin, ofloxacin, fleroxacin, and lomefloxacin. The MIC of sparfloxacin for 90% of the members of the family Enterobacteriaceae tested was 0.5 microgram/ml (range, 0.06 to 4.0 micrograms/ml); only for members of the genera Serratia, Citrobacter, and Providencia were MICs above 1 microgram/ml. Some 90% of Pseudomonas aeruginosa isolates were inhibited by 8 micrograms of the drug per ml. The MICs for 90% of Staphylococcus spp. and Enterococcus faecalis were 0.12 and 2 micrograms/ml, respectively. All (100%) Streptococcus pneumoniae strains were inhibited by 0.5 microgram/ml. The inoculum size had little effect on either the MIC or the MBC of sparfloxacin. An increase in the magnesium concentration from 1.1 to 8.4 mM increased the MIC between 2 and 10 times, depending on the genus tested. Sparfloxacin was less active at pH 5. The antibacterial activity of sparfloxacin against gram-positive bacteria was generally higher than those of the quinolones with which it was compared; against Streptococcus pneumoniae, sparfloxacin was four- and eightfold more active than ofloxacin and ciprofloxacin, respectively. The activity of sparfloxacin against gram-negative rods was generally comparable to that of ciprofloxacin except against Enterobacter and Acinetobacter spp., Pseudomonas cepacia, Xanthomonas maltophilia, and Alcaligenes and Flavobacterium spp., against which sparfloxacin was the most active quinolone.

Anti-Infective Agents↗

[Detection of cytomegalovirus in urine by the shell-vial technique: usefulness of diluting the sample].

To assess the toxicity of urine samples on human fibroblast cell monolayer using Shell-vial technique for cytomegalovirus antigen detection. A total of 227 urine samples were processed, inoculated on Shell-vial simultaneously, being either diluted (1:1) and non diluted in transport media. After 24-48 hours incubation, the fibroblast cells monolayer was stained using fluorescein-marked monoclonal anti-cytomegalovirus antibodies. Cytomegalovirus was detected in 9.6% of samples inoculated with diluted urine, and in 5.2% of samples inoculated with non-diluted urine. Destruction of monolayer cells was seen in 13.2 and 22.4, respectively. With Shell-vial technique for detecting cytomegalovirus in urine samples, a high number of positive results was obtained using diluted urine. Also a significant minor destruction of cells monolayer was observed with the same inoculum.

Antibodies, Monoclonal↗