Biomedical subjects

I Catalá

Publications and source records attributed to I Catalá.

6 recordsLinked to original sources

PubMed1996

Protected bronchoalveolar lavage in the diagnosis of ventilator-associated pneumonia.

The aim of this study was to evaluate the diagnostic efficacy of protected bronchoalveolar lavage (PBAL) in ventilator-associated pneumonia (VAP), and to determine the effect of antibiotic therapy on its microbiological and cytological results. We prospectively studied 102 episodes of suspected VAP in 93 patients. Subsequent follow-up confirmed VAP in 35 of the 102 (34%) cases. In 55 of the 102 (55%) VAP was ruled out, and the diagnosis remained undetermined in 12 of the 102 (12%) episodes. In the VAP group, 30 of the 35 (86%) PBAL (> or = 10(4) colony-forming units (cfu)-mL-1) cultures were positive. In the non-VAP group, 5 of the 55 (9%) PBAL cultures were positive. A Giemsa stain of PBAL samples was performed in 32 of the 35 cases of VAP. Intracellular organisms (ICO) were found in 24 of the 32 (75%) cases. Seven of the other eight cases without evidence of ICO were already on antibiotics. In the non-VAP group, ICO were present in only 1 out of 55 (2%) cases. The mean ICO was significantly higher in the group who had not received antibiotics when compared with those patients previously treated for less than 48 h (p < or = 0.01) and those treated for more than 48 h (p = 0.009). The sensitivity of protected bronchoalveolar lavage quantitative cultures was 87% and the specificity 91%. The sensitivity of cytological analysis for intracellular organisms was 75% and the specificity 98%. According to our results, if the patient is already on antibiotics, the direct examination of protected bronchoalveolar lavage fluid is less reliable, although still helpful.

Anti-Bacterial Agents↗

PubMed1993

Experimentally induced laminar necrosis, status verrucosus, focal cortical dysplasia reminiscent of microgyria, and porencephaly in the rat.

Different types of cortical malformation were produced, following focal cortical freezing, electrocoagulation, focal cortical aspiration or gentle brushing of uncovered meninges, in newborn or 1- to 3-day-old rats. Malformations included laminar necrosis of the cerebral cortex, status verrucosus, focal cortical dysplasia reminiscent of microgyria, and porencephaly. Similar procedures from postnatal day 4 onwards, at a time when a reactive astrogliosis is possible, produced cavitating infarcts and tissue scars. Cytoarchitectonic studies revealed an abnormal distribution of different types of pyramidal and non-pyramidal neurons in these malformations. These indicated three subtypes of focal cortical dysplasia, which probably depend on different pathogenic mechanisms. Autoradiographic studies with [3H] methylthymidine showed normal positioning of late-generated neuroblasts in the cerebral cortex, thus suggesting preserved migration. The present experimentally induced cortical malformations are useful models of similar cortical abnormalities in humans.

Animals↗

PubMed1993

Caroli's disease versus polycystic hepatic disease. Differential diagnosis with Tc-99m DISIDA scintigraphy.

Four patients with multiple hepatic cysts were studied: two were diagnosed with Caroli's disease (CD) and two with polycystic hepatic disease (PHD). In CD, hepatic scintigraphy with Tc-99m DISIDA showed areas of focally increased radiotracer accumulation that persisted more than 120 minutes, whereas in PHD, areas of focally decreased radiotracer accumulation were observed with normal liver washout and biliary excretion. When multiple hepatic cysts are shown by abdominal echography or CT scan, hepatic scintigraphy with Tc-99m DISIDA should be performed. This examination is safe and noninvasive, and permits differential diagnosis between CD and PHD.

Adult↗

PubMed1991

Unlayered polymicrogyria: structural and developmental aspects.

Unlayered polymicrogyria was analyzed in four patients with established lesions and in one 19- to 20-week-old fetus with lesions in a formative stage whose mother had suffered a serious accident two weeks before. Polymicrogyria occurred at the banks of porencephalic, sylvian clefts in three cases, and bilaterally in the watershed areas of the parieto-occipital lobes in a fourth case. Periventricular neuronal heteropias were found in these cases. Cortical lesions in the fetus were distributed along the watershed zones of the middle cerebral artery. Serial sections revealed that the appearance of microgyria was the result of radial tissue cleavage of the cerebral cortex, as shown by the increased numbers of blood vessels and astrocytes forming a tissue scar. Golgi studies disclosed that the different neuronal types were positioned at the apropriate cortical depths in the microgyric cortex. On the other hand, heterotopic nodules were composed of pyramidal and non-pyramidal neurons usually found in the upper cortical layers in the normal cortex. These features indicate that unlayered polymicrogyria is produced by circulatory failure occurring before the end of the period of neuroblast migration to the cortical plate. Circulatory failure in the radial and unbranched arteries that penetrate from the meningeal surface and vascularize the cerebral cortex at midgestation may result in radial tissue necrosis of the cortical mantle, whereas failure in the distal, terminal territories of these blood vessels may damage radial glial fibres and impair the last migration of neuroblasts. The particular morphology of this cortical abnormality finally depends on the imbalance in the tangential growth of adjoining cortical areas variably destroyed by tissue necrosis.

Abnormalities, Multiple↗

PubMed1988

Decreased numbers of dendritic spines on cortical pyramidal neurons in dementia. A quantitative Golgi study on biopsy samples.

The number of dendritic spines on the apical dendrites of layer III pyramidal cells was counted in cerebral biopsies, processed in part according to the rapid Golgi method, which had been performed for diagnostic purposes on patients suffering from dementia of different origins. The samples were from cases affected by Alzheimer's disease (3 patients), Parkinson's disease and dementia (1 patient), Creutzfeldt-Jacob disease (4 patients), Pick's disease (1 patient) and dementia paralytica (1 patient). Spines were counted on consecutive segments of the apical dendrite along the 500-microns proximal region from the cell body. A significant decrease in the number of spines was observed in almost every segment of the apical dendrite in demented patients when compared with similar measurements carried out in age-matched controls (p less than 0.01-0.001); Mann-Whitney U-test. Decreased numbers of dendritic spines may result in reduced inputs on cortical neurons and may be a consistent morphological substrate for the impaired mental status in cortical dementia.

Cerebral Cortex↗

PubMed1986

Marrow aplasia during high dose mebendazole treatment.

A patient with chronic liver disease was treated with large doses of mebendazole for a hepatic hydatid cyst. Eighteen days after beginning treatment he developed marrow aplasia which reverted to normal after the drug was stopped. This is the marrow aplasia which reverted to normal after the drug was stopped. This is the sixth patient described as developing marrow aplasia when treated with large doses of mebendazole. We suggest that the aplasia is related to the dose of the drug, and that the patient's chronic liver disease was an important factor in its genesis. Patients treated with large doses of mebendazole should have their blood counts monitored during treatment.

Aged↗