PubMed Health⌕ Search

Biomedical subjects

A Martos

Publications and source records attributed to A Martos.

17 recordsLinked to original sources
PubMed2002

Detection of cytogenetic alterations and blood cell changes in natural populations of carp.

A field study was conducted to investigate the appearance of alterations in the peripheral blood cells of wild populations of fish. Two aspects were evaluated: the appearance of cytogenetic effects, measured as increases on micronuclei frequencies, and the appearance of haematological effects by checking changes in the relative proportion of the different blood cell types. For this purpose common carp (Cyprinus carpio) were caught from four areas along a Spanish river. Three areas were located under the influence of chemical industries and/or a nuclear power plant. The fourth was a clean reference area. Flow cytometry was used to quantify the appearance of micronuclei on the same day of sampling and also after two and twelve months. The alterations in the relative proportion of cell types were counted in blood smears stained with Giemsa. Increases in micronuclei frequencies were observed in fish living in supposedly polluted areas. Alterations of the relative proportions of blood cells were manifested as an increase in white blood cells and as a decrease in red blood cells vs. control area. Since accidental spills have not been reported over this period of time, the alterations observed could suggest that fish are suffering chronic effects due to low level contamination associated with the sampled areas.

Animals↗
PubMed2002

Experimental study of the efficacy of vancomycin, rifampicin and dexamethasone in the therapy of pneumococcal meningitis.

The object of the study was to assess the efficacy of rifampicin and the combination of rifampicin plus vancomycin in a rabbit model of experimental penicillin-resistant pneumococcal meningitis. We also studied the effect of concomitant dexamethasone on the CSF antibiotic levels and inflammatory parameters. The rabbit model of pneumococcal meningitis was used. Groups of eight rabbits were inoculated with 106 cfu/mL of a cephalosporin-resistant pneumococcal strain (MIC of cefotaxime/ceftriaxone 2 mg/L). Eighteen hours later they were treated with rifampicin 15 mg/kg/day, vancomycin 30 mg/kg/day or both plus minus dexamethasone (0.25 mg/kg/day) for 48 h. Serial CSF samples were withdrawn to carry out bacterial counts, antibiotic concentration and inflammatory parameters. Rifampicin and vancomycin promoted a reduction of >3 log cfu/mL at 6 and 24 h, and cfu were below the level of detection at 48 h. Combination therapy with vancomycin plus rifampicin was not synergic but it had similar efficacy to either antibiotic alone and it was able to reduce bacterial concentration below the level of detection at 48 h. Concomitant use of dexamethasone decreased vancomycin levels when it was used alone (P< 0.05), but not when it was used in combination with rifampicin. Rifampicin alone at 15 mg/kg/day produced a rapid bactericidal effect in this model of penicillin-resistant pneumococcal meningitis. The combination of vancomycin and rifampicin, although not synergic, proved to be equally effective. Using this combination in the clinical setting may allow rifampicin administration without emergence of resistance, and possibly concomitant dexamethasone administration without significant interference with CSF vancomycin levels.

Animals↗
PubMed2000

Effects of acute and chronic maprotiline administration on inhibitory avoidance in male mice.

The effects of acute and chronic administration of maprotiline (5, 10 or 20 mg/kg, intraperitoneally) were assessed on inhibitory avoidance in male mice. Acute administration of maprotiline before training did not effect training phase latencies, but impaired performance (i.e. produced shorter latencies) in the test at doses of 5 and 20 mg/kg. When given after training, the drug did not modify test latencies at any of the doses used. Chronic administration for 21 days (interrupted 24 h before training) also shortened latencies in the test but not in training. An experiment on the acute effects of maprotiline on analgesia (determination of flinch and jump thresholds for increasing electric foot shock levels), at the doses stated, was carried out on naive animals. No analgesic effect of the drug was found. Taken together, the results indicate that acute maprotiline produces anterograde amnesia, and tolerance does not appear after 21 days of treatment.

Animals↗
PubMed1995

Steroids do not enhance the risk of developing tuberculosis or other AIDS-related diseases in HIV-infected patients treated for Pneumocystis carinii pneumonia.

OBJECTIVE: To evaluate the risk of developing tuberculosis or other AIDS-related diseases (ARD) in HIV-infected patients treated with corticosteroids as adjunctive therapy for Pneumocystis carinii pneumonia (PCP). DESIGN: Retrospective study. SETTING: Infectious Disease Service of a 1000-bed university teaching hospital in Barcelona, Spain. PATIENTS: HIV-infected patients diagnosed with PCP from 1985 to 1992. Patients were classified into two groups: steroid (group A) and non-steroid (group B) adjunctive therapy. Baseline characteristics, antibiotherapy, dose and duration of steroidal treatment were analysed. Endpoints were either the development of tuberculosis or other ARD or death. RESULTS: From the 129 patients included in this study 72 were in group A and 57 in group B. No differences between groups were observed in baseline characteristics or mean follow-up period (15 versus 14 months, respectively). The mean total dose of steroids was 420 mg (range, 160-1260 mg) methylprednisolone or its equivalent in dexamethasone, with a mean treatment duration of 12 days (range, 4-33 days). No differences were found in the occurrence of tuberculosis or other endpoints in the first 6 months of follow-up. In addition, the cumulative rate of developing tuberculosis was 7% in group A and 12% in group B at 12 months of follow-up, and 13 versus 12% at 24 months (P = 0.622, Mantel-Cox): 4 versus 4% at 12 months and 27 versus 24% at 24 months (P = 0.873) for non-tuberculosis mycobacterial infection, and 40 versus 42% at 12 months, and 88 versus 66% at 24 months (P = 0.330) for non-mycobacterial ARD. The cumulative survival rate was 79 versus 71% and 46 versus 34% at 12 and 24 months, respectively (P = 0.526). CONCLUSIONS: Our data suggest that the use of corticosteroids during PCP in HIV-infected patients at the doses and for the duration used in our patients did not enhance the risk of developing or relapsing tuberculosis or other ARD.

AIDS-Related Opportunistic Infections↗
PubMed1995

Influence of dexamethasone on efficacy of ceftriaxone and vancomycin therapy in experimental pneumococcal meningitis.

Using a rabbit model of meningitis, we sought to determine whether concomitant use of dexamethasone affects the penetration and efficacy of ceftriaxone or vancomycin in cerebrospinal fluid. Rabbits were inoculated with a penicillin-sensitive strain of Streptococcus pneumoniae and treated with ceftriaxone or vancomycin with or without dexamethasone. In the ceftriaxone-treated groups, no statistically significant differences were seen between the group treated with dexamethasone and that without dexamethasone; however, in the vancomycin-treated groups we found statistically significant lower cerebrospinal fluid vancomycin levels at 2 h in the dexamethasone-treated rabbits and differences in bacterial killing.

Animals↗
PubMed1995

Use of elastin fibre detection in the diagnosis of ventilator associated pneumonia.

BACKGROUND: Elastin fibre detection could be a simple and reliable marker of ventilator associated pneumonia. To confirm this, a prospective study was undertaken to evaluate the diagnostic yield of elastin fibre detection in the diagnosis of ventilator associated pneumonia. METHODS: Seventy eight mechanically ventilated patients were evaluated by examining endotracheal aspirates for the presence of elastin fibres. All patients were previously treated with antibiotics. Quantitative bacterial cultures of endotracheal aspirates and protected specimen brush samples were also performed. Patients were classified into three diagnostic categories: group 1, definite pneumonia (n = 25); group 2, probable pneumonia (n = 35); and group 3, controls (n = 18). RESULTS: Patients with definite and probable pneumonia were grouped together. The presence of elastin fibres in endotracheal aspirate samples was more frequent in groups 1 and 2, being found in 19 of the 60 patients compared with five of the control group. Although the presence of elastin fibres had a low sensitivity (32%), it was a reasonably specific marker (72%) of pneumonia. This specificity increased to 86% and 81% respectively when only Gram negative bacilli and Pseudomonas aeruginosa pneumonia were considered. Again, calculated sensitivity was 43% and 44% when analysing cases infected by Gram negative bacilli and Ps aeruginosa, respectively. The negative predictive value of the detection of elastin fibres in pneumonia caused by Ps aeruginosa was 81%. Detection was more frequent with infection by Gram negative bacilli (14/19), particularly with Ps aeruginosa (8/14). By contrast, pneumonia due to Gram positive cocci or non-bacterial agents uncommonly resulted in positive elastin fibre preparations (4/19, 21%). When analysing patients with and without chronic obstructive pulmonary disease, the diagnostic value of elastin fibre detection did not change. CONCLUSIONS: Potassium hydroxide preparation of elastin fibres is a rapid and simple specific marker of ventilator associated pneumonia and may be a useful technique to help diagnose pulmonary infections in mechanically ventilated patients, although this assessment is at present limited to patients without adult respiratory distress syndrome.

Adult↗
PubMed1995

[Protective effect of dexamethasone and phenytoin in the treatment of experimental pneumococcal meningitis].

BACKGROUND: Pneumococcal meningitis has a high morbidity and mortality rate despite effective antibiotherapy, probably due to an exaggerated inflammatory response of the CNS. The use of dexamethasone and phenytoin reduced mortality in adults with pneumococcal meningitis. OBJECTIVE: We sought to determine the effect of dexamethasone, phenytoin or the association of both in several inflammatory parameters in experimental bacterial meningitis. METHODS: The study was performed using a modification of the rabbit model of Dacey and Sande. New Zealand white rabbits were intracisteranly inoculated simultaneously with heat-killed S. pneumoniae R6 dexamethasone, phenytoin or both. CSF leucocytes and concentration of proteins and lactate were determined over 6 hours, as well as the presence of brain edema. RESULTS: Treatment with dexamethasone alone or in association with phenytoin reduced all inflammatory parameters. The administration of phenytoin alone did not prevent an increase of CSF leucocytes or protein concentration, but did prevent the development of brain edema. A trend to wards a protective effect on the lactate concentration was observed. CONCLUSIONS: Our results gives support to the antiinflammatory effect of dexamethasone in experimental pneumococcal meningitis, and suggest that phenytoin may have also a protective effect on brain ischemia. This protective action and the prevention of brain edema could contribute, beyond its anticonvulsivant properties, to the great reduction in the mortality rate observed in some clinical studies in patients with pneumococcal meningitis.

Animals↗
PubMed1993

Specificity of endotracheal aspiration, protected specimen brush, and bronchoalveolar lavage in mechanically ventilated patients.

The specificity of the different techniques used to diagnose ventilator-associated pneumonia is still a matter of controversy. To investigate the specificity of endotracheal aspiration (EA), protected specimen brush (PSB), and bronchoalveolar lavage (BAL) quantitative cultures, we studied 27 consecutive mechanically ventilated (MV) patients (> 72 h) without clinical or radiographic evidence of pulmonary infection. Comparing different thresholds for quantitative cultures (from 10(3) through 10(6) CFU/ml), the lowest rate of false positive results was obtained using 10(6) for EA, 10(5) for PSB, and 10(6) for BAL. Using 10(6) CFU/ml for EA, 10(4) CFU/ml for PSB, and 10(5) CFU/ml for BAL as cutoff points, we obtained the following specificities: 85, 85, and 78% for the three techniques, respectively. A bacterial index of 8 was the best threshold to get a low percentage of false positive results for all techniques except for EA (0% for PSB and 12% for BAL). There were reasonable qualitative agreements (PSB versus EA = 58%; BAL versus EA = 69%; and PSB versus BAL = 62%) and poor quantitative correlations between concomitantly isolated microorganisms from the three types of samples. Quantitative cultures of EA, PSB, and BAL may show a considerable percentage of false positive results at the respective cutoff points usually accepted. Increasing the thresholds for quantitative cultures, albeit loosing sensitivity, may rule out better the absence of pulmonary infection in MV patients.

Bacteria↗
PubMed1993

Gastric and pharyngeal flora in nosocomial pneumonia acquired during mechanical ventilation.

We studied the interrelations between gastric, pharyngeal, proximal, and distal airway bacterial flora in ventilator-associated pneumonia (VAP) on 36 patients with nosocomial pneumonia acquired during mechanical ventilation (MV) and 27 mechanically ventilated control subjects without pulmonary infection. Gastric, pharyngeal, and endotracheal (EA) sampling for quantitative cultures were performed upon all patients, as well as fiberoptic bronchoscopy with protected specimen brush (PSB) sampling. Mean bacterial and fungi colony counts were significantly increased in pharyngeal, EA, and PSB samples in patients with VAP compared with control subjects. The overall increase in colonization was due to gram-positive cocci in all samples. In addition, gram-negative bacilli and fungi mean counts increased significantly in PSB pneumonia samples versus control samples. However, mean gastric colonization was similar in both patients with VAP and control subjects. In the former group there was an increase in coincident microorganisms isolated from gastric, pharyngeal, and EA samples in relation to PSB samples compared with control samples. Among the different quantitative cultures analyzed, only those obtained from EA significantly correlated with PSB cultures in patients with pneumonia (r = 0.67, p = 0.001). In summary, the present study shows that the coincidence between microorganisms isolated in PSB cultures and those from gastric and oropharynx increase in MV patients with pneumonia, indicating that both reservoirs play a key role in the pathogenesis of pneumonia. Conceivably, preventing both gastric and pharyngeal colonization may reduce the incidence of ventilator-associated pneumonia. From all the noninvasive samples studied only endotracheal aspirate cultures were useful for inferring the etiology of some VAP pneumonias.

Bacteria↗
PubMed1992

[Pulmonary cryptococcosis in AIDS].

We present here three AIDS patients with disseminated cryptococcal infection and lung involvement. Two patients presented with respiratory symptoms and in the third one, pulmonary disease was only a radiologic finding. Chest X-ray films showed an interstitial pattern in two cases and pulmonary cavitation in one case. One patient has also simultaneous infection by P. carinii. Diagnosis was established by culture from bronchoalveolar lavage in all cases and also by non-induced sputum exam in two cases. All patients were treated with amphotericin B, with good clinical outcome, and without relapses under maintenance therapy with fluconazole. Cryptococcosis must be included in differential diagnosis of AIDS patients with diffuse interstitial lung infiltrates. The presence of C. neoformans in respiratory samples does not rule out the existence of other opportunistic infections, and therefore bronchoalveolar lavage is advisable.

AIDS-Related Opportunistic Infections↗
PubMedDate not supplied

[Changes in the small cerebral vessels in the acquired immunodeficiency syndrome].

In the necropsy exam of the brains of 13 patients with acquired immune deficiency syndrome (AIDS) cerebrovascular lesions were seen in 5 cases, three of them having AIDS encephalopathy. Hyalinosis was noted in 3 cases, and endarteritis obliterans and fibrinoid necrosis in one case each; both of them had associated perivascular lymphocytic infiltrates. Cerebral infarction was observed in one case, but no hemorrhages were seen. The neuropathological anomalies in four children affected with the AIDS are reported too, being an extensive calcified vasculopathy and changes suggesting active AIDS encephalopathy the main findings.

AIDS Dementia Complex↗