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J Muñoz

Publications and source records attributed to J Muñoz.

At least 73 records · Page 4Linked to original sources
PubMed1998

Methodological aspects of assessing phagocytosis of Vibrio anguillarum by leucocytes of gilthead seabream (Sparus aurata L.) by flow cytometry and electron microscopy.

In this paper we optimize a flow cytometric method for evaluating the phagocytic activity of leucocytes in gilthead seabream (Sparus aurata L.) and characterize the phagocytic cells observed. Optimal conditions were established for the fluorescein-labelling and analysis of the bacterium Vibrio anguillarum by flow cytometry. Head-kidney leucocytes were incubated with the heat-killed fluorescein isothiocyanate (FITC)-labelled bacteria for different periods, during which the kinetics of phagocytosis was studied. Attached and interiorized bacteria were distinguished. Although phagocytic ability reached a maximum after 60 min, phagocytic capacity reached its maximum at 20 min. The amount of ingested bacteria per phagocyte was estimated from the mean fluorescence of the leucocytes. Cytochalasin B or colchicine was used to inhibit phagocytosis. Monocyte-macrophages and acidophilic granulocytes showed phagocytic activity as demonstrated by transmission electron microscopy. In conclusion, the technique presented allows the screening of thousands of cells, and individual cell evaluation, by quantifying interiorized particles in fish phagocytes. Our ultrastructural results demonstrate that V. anguillarum is actively phagocytized by seabream macrophages and acidophilic granulocytes.

Animals↗
PubMed1998

Dermatophagoides sp. and IgE anti-D. pteronyssinus and D. farinae detection in a Venezuelan community at more than 2000 m above the sea level.

BACKGROUND: It has been reported that the concentration of Dermatophagoides sp. population, the main trigger of asthma in sensitized atopic subjects, is inversely related with altitude and probably directly with humidity and that this population are scarcely found over 1750 m above sea level. OBJECTIVE: We studied the presence of Dermatophagoides sp. in a Venezuelan community between 2040 and 2600 m above sea level, and also the IgE response to D. pteronnyssinus and D. farinae in atopic subjects living on that region. METHODS: The presence of Dermatophagoides sp. was determined by microscopic identification of mites in dust, obtained by brushing the mattresses surface in 93 randomly selected houses between 2040 and 2600 m above sea level. The indoor relative humidity was also measured. The specific IgE serum levels were studied in 65 subjects classified as asthmatics, allergic non-asthmatics and non-allergic. RESULTS: A mean concentration of 188 mites/g of room dust was determined in 82.4% of houses with an indoor relative humidity ranging from 89% and 92% independently of altitude. The density of Dermatophagoides sp. was sufficiently high to sensitize the atopic subjects, IgE levels were 6.8 PRU mean value for asthmatic, against 0.38 PRU in non-atopic. CONCLUSIONS: We conclude that: (a) Dermatophagoides sp. can be found up to 2600 m above sea level in a Venezuelan neotropical region where a high indoor relative humidity is characteristic of most dwellings; (b) sensitization by D. pteronyssinus and D. farinae were demonstrated in atopic subjects resident at that region.

Allergens↗
PubMed1998

Stevens-Johnson syndrome caused by indinavir.

A case is presented of an HIV-infected man who developed Stevens-Johnson syndrome shortly after the initiation of treatment with indinavir. This is the first case ever reported of this adverse drug reaction occurring with an HIV protease inhibitor.

Adult↗
PubMed1998

[Evaluation of the hemodynamic effects of tumor necrosis factor alpha factor in rats with portal hypertension using the radioactive microsphere technique].

UNLABELLED: This study was aimed at investigating the effects of blocking circulating TNF on the hyperdynamic circulatory state developed in rats with portal vein stenosis (PVS), and the factors mediating the hemodynamic action of this cytokine in this setting. MATERIALS AND METHODS: Murine antiTNF polyclonal antibodies (100 microgram) or placebo were intravenously injected into PVS rats (n = 24) before and 4 days after PVS. Hemodynamic studies were performed the day after the last antiTNF injection. RESULTS: Short-term TNF inhibition led to reductions in cardiac index (p < 0.05) and portal venous inflow (p < 0.01), and significant increases in splanchnic and systemic vascular resistances. Portal pressure was unchanged, but portal-systemic shunting was decreased (p < 0.05). CONCLUSION: TNF plays a key role in promoting the development of the hyperdynamic state of portal hypertension. The effect of TNF is mediated through an increased release of nitric oxide.

Animals↗
PubMed1998

BAX somatic frameshift mutations in endometrioid adenocarcinomas of the endometrium: evidence for a tumor progression role in endometrial carcinomas with microsatellite instability.

Microsatellite instability (MI) has been observed in endometrioid adenocarcinomas of the endometrium, either arising sporadically or in association with the hereditary colon cancer syndrome. Genes known to contain mononucleotide short tracts in their coding sequence are regarded as targets for mutations in these tumors. BAX is a proapoptotic gene that contains a tract of eight consecutive deoxyguanosines in its third coding exon. DNA of 26 patients with endometrial carcinoma was extracted from blood and from fresh-frozen and paraffin-embedded tumor tissue. For MI analysis, microsatellite loci on chromosomes 3, 5, 10, 12, and 18 were amplified by PCR. Frameshift mutations in the (G)8 tract of BAX were detected by single-strand conformation polymorphism (SSCP) analysis. MI at three or more loci was detected in 13 cases. BAX frameshift mutations were detected in seven MI+ tumors (53.8%), but in none of the 13 MI- neoplasms. In two cases, identical BAX frameshift mutations were detected in different areas of the neoplasm, whereas in the other five cases, BAX mutations were heterogeneously distributed throughout the tumor. Immunostaining with antibodies against the carboxy terminus of BAX protein was very useful in assessing the heterogeneous distribution of BAX frameshift mutations in the neoplasms. The results suggest that BAX frameshift mutations are frequent in endometrial carcinomas with MI, probably playing a role in the process of tumor progression of these neoplasms.

Base Sequence↗
PubMed1997

Diagnostic imaging of tibial periosteal ganglion.

A case of a soft tissue tumor situated in the anterior surface of the proximal end of the tibia in an adult patient is demonstrated by conventional radiographs, CT, and MRI. The lesion was well defined with respect to the adjacent soft tissue. The CT exam showed a soft tissue mass with external cortical erosion and thick spicules by periosteal reaction. On T1-weighted images the mass was homogeneous and of low signal intensity, whereas on T2-weighted images it showed a high signal intensity, with some septa in the mass. The differential considerations include a periosteal chondroma, a lipoma, a subperiosteal hematoma, an inflammatory process, a giant cell tumor of tendon sheath, and a parosteal osteosarcoma. The CT and MR features of these entities are reviewed as an aid in differential diagnosis of the periosteal ganglion.

Adult↗
PubMed1997

Accuracy of portal and forearm blood flow measurements in the assessment of the portal pressure response to propranolol.

BACKGROUND/AIMS: The portal pressure response to propranolol varies significantly in individual patients with cirrhosis. At present, propranolol responders can be identified only by measuring the hepatic venous pressure gradient. The aims of this study were: 1) to investigate whether the noninvasive monitoring of portal blood flow by pulsed Doppler ultrasound and forearm blood flow by strain-gauge plethysmography can predict the hepatic venous pressure gradient response to propranolol in patients with cirrhosis, and 2) to analyze the factors that may influence this response. METHODS: Hemodynamic measurements were undertaken in 80 patients with cirrhosis before and after receiving propranolol (0.15 mg/kg i.v., n = 60) or placebo (n = 20). RESULTS: No changes were observed in the placebo group. Propranolol lowered (p < 0.01) hepatic venous pressure gradient from 17.6 +/- 3.8 to 14.7 +/- 3.8 mmHg, portal blood flow from 1122 +/- 363 to 897 +/- 332 ml/min and forearm blood flow from 7.52 +/- 3.1 to 6.12 +/- 2.3 ml/min%. Changes in hepatic venous pressure gradient were correlated (p < 0.01) with those of portal blood flow (r = 0.82) and forearm blood flow (r = 0.54). The reduction in hepatic venous pressure gradient was > 20% in 23 patients ("responders"). The accuracy of portal Doppler flowmetry in identifying responders was higher than that of forearm plethysmography (88.3 vs. 68.3%, p < 0.05). Multivariate analysis proved that previous variceal bleeding was the only factor independently associated with a lack of response to propranolol (relative risk 3.42, 95% CI 1.5-7.4, p < 0.01). Hepatic venous pressure gradient reduction by propranolol was higher in non-bleeders than in bleeders (-19.9 +/- 9.4 vs. -11.3 +/- 8.6%, p < 0.01). CONCLUSIONS: Portal Doppler ultrasound can be used as a reliable surrogate indicator of the hepatic venous pressure gradient response to acute propranolol administration. In addition, our study indicates that this response is mainly influenced by previous variceal hemorrhage.

Adrenergic beta-Antagonists↗
PubMed1997

Photosensitive polyurethanes applied to the development of CHEMFET and ENFET devices for biomedical sensing.

Chemical microsensors based on ion-selective field effect transistor (ISFET) transducers with ion-selective and enzymatic membranes have been fabricated. In this case, photolithographically patterned membranes based on acrylated urethanes have been developed and applied onto the gate area of ISFET chips. Aliphatic urethane diacrylate has been used for K+ and NH+4 membranes, while a photocurable hydrogel formulation based on other type of acrylated urethane has been optimized for urea-FET sensors. Resulting potassium and ammonium sensors show similar performances to those found when PVC membranes are employed. An integrated packaging process for ISFET-based sensors has been developed giving the possibility of carrying out most of the encapsulation on wafer level. For this purpose, a photocurable polyurethane encapsulant formulation has been optimized to be microstructured by photolithography. Finally, a preliminary study of biocompatibility of photosensitive formulations containing urethane oligomers has been performed in order to examine future applications in biomedical and clinical analysis.

Biosensing Techniques↗
PubMed1997

Use of subdiaphragmatic bupivacaine instillation to control postoperative pain after laparoscopic surgery.

Although postoperative pain has been reduced significantly since the advent of laparoscopic surgery, many patients still complain of moderate abdominal and shoulder pain during the first 48 to 72 h after surgery. In this study, the effect of subdiaphragmatic instillation of bupivacaine after laparoscopic cholecystectomy was investigated. The evaluation of postoperative pain was done according to a numerical verbal scale and the dose of analgesia required. The results showed a considerable reduction of postoperative pain during the first 48 h after surgery in patients who received bupivacaine instillation. Although the literature shows certain controversy as to the effects of similar methods, our study concludes that instillation of a long-acting anesthetic, such as bupivacaine, into the subdiaphragmatic space after laparoscopic procedures is effective in postoperative pain reduction.

Adult↗
PubMed1997

[Contribution of thalamic somatosensory evoked potentials to stereotaxic thalamometry].

INTRODUCTION: In order to use short latency somatosensory thalamic evoked potentials (PES) to locate therapeutic targets in functional surgery, thalamic PES were recorded during stereotactic thalamotomy in 25 patients with Parkinson's disease, using a concentric bipolar semi-micro-electrode, 4 mm in diameter. In the 72 trajectories planned. 628 registers were made, obtaining 314 PES in 55 trajectories. These recordings were divided into 5 groups, according to the electrical variables evaluated in each case (absolute latency, inter-peak latency, absolute amplitude and number of phases). MATERIAL AND METHODS: The electrophysiological characteristics of the PES groups obtained, and the spatial representation of these in a tridimensional system of coordinates, is shown. We analyze the sequence of the groups of potentials in each of the trajectories followed. CONCLUSIONS: We consider that the limit between adjacent nuclear edges, ventral intermediate (Vim)-ventro-caudal (Vc), may be represented by the transition of potentials in group 1 to potentials in group 4 and/or potentials of group 3 to those of group 2. This study shows that thalamic PES are useful for locating targets during stereotactic thalamotomy.

Adult↗
PubMed1997

[Historical cohort study on bacterial pneumonias as predictors of the progression of the human immunodeficiency virus disease].

BACKGROUND: Recognition of the importance of bacterial pneumonias in the context of HIV infection has continuously grown throughout the pandemia. It has recently been suggested that these may be predictors of progression of the disease. PATIENTS AND METHODS: The evolution of an historic cohort of patients with HIV infection who were studied in 1989 with pneumonia regarding the presentation of AIDS or death was investigated. A control cohort was established, being age matched for sex, CD4 lymphocyte count, previous HIV disease and the use of zidovudine. Kaplan-Meier curves of survival without AIDS were made and compared by the logarythmic range test. Other predictors of progression were studied by the Cox models. RESULTS: Forty-nine patients were studied in each group, with a total of 121 and 153 patients/year of follow up. Final events were counted in 33 and 27 cases, respectively (p = 0.11). The relative risk of progression was 1.55 (confidence interval of 95%, 0.93 to 2.56) for the group of pneumonias. The estimated relative risk (hazard) performed by a Cox model of proportional risks was however 1.85 (confidence interval of 95%: 1.05 to 3.25, p < 0.05) when the lymphocyte count adjustment was carried out according to the real values rather than by categories. CONCLUSIONS: The results of this historic cohort study support the existence of an association between history of bacterial pneumonia and the risk of HIV disease progression.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Human granulocytic ehrlichiosis: a case series from a medical center in New York State.

BACKGROUND: Human granulocytic ehrlichiosis (HGE) is a newly described illness with few reports in the literature. OBJECTIVE: To describe the clinical and laboratory feature of HGE. DESIGN: Case series. SETTING: Tertiary care facility in New York State. PATIENTS: 18 adult patients with HGE. MEASUREMENTS: Epidemiologic, clinical, and laboratory features; treatment; and outcome of patients with HGE. RESULTS: Patients presented with such symptoms as fever (94%) and myalgia or arthralgia (78%). Thirteen patients (71%) recalled being bitten by a tick before onset of symptoms. Leukopenia or thrombocytopenia was seen in 82% of patients, and abnormal liver enzyme levels were seen in 81%. Results of polymerase chain reaction were positive in 9 of 12 patients (75%); morulae were seen in 3 of 12 patients (25%); and the agent that causes HGE was cultured from 2 patients. All but one patient (94%) developed antibodies to Ehrlichia equi. Five patients (28%) were briefly hospitalized, and none died. All patients were successfully treated with doxycycline. CONCLUSIONS: The illness associated with HGE in these patients from the northeastern United States was more mild than that originally described in reports of HGE in the midwestern United States.

Adult↗
PubMed1996

Overexpression of the 67-kD laminin receptor correlates with tumour progression in human colorectal carcinoma.

The high affinity 67-kD laminin receptor (67LR) is a cell surface protein whose expression is increased in a number of human carcinoma models. To date, 67LR expression in colorectal carcinomas has been examined in a small number of cases. 67LR expression has been immunohistochemically analysed in a large series of human colorectal neoplasms, using the MLuC5 monoclonal antibody. The study included 59 samples of non-neoplastic mucosa, 45 polyps (11 hyperplastic, 34 adenomas), 196 carcinomas, and lymph node metastases of 87 carcinomas. Epithelial cells of normal mucosa and hyperplastic polyps were negative or showed weak positivity in the paranuclear and apical areas of the cytoplasm. In adenomas and carcinomas, the staining was stronger, with a membranous or cytoplasmic pattern. The expression of 67LR correlated significantly with the progression from normal mucosa (22 per cent) to adenoma (44 per cent), carcinoma (61 per cent), and lymph node metastasis (75 per cent) (P < 0.0001). Expression of the laminin receptor showed a tendency to be more frequently positive in advanced stage (III+IV; 67 (III+IV; 67 per cent) when compared with early stage (I+II) carcinomas (54 per cent). The difference, however, was not statistically significant (P = 0.058). In addition, 14 out of 28 (50 per cent) primary carcinomas without 67LR expression became positive in lymph node metastases, while most (86 per cent) of the MLuC5-positive primary carcinomas were also immunoreactive in metastases. In conclusion, these results indicate that 67LR is up-regulated in the progression of human colorectal carcinomas and may play a role in the local and metastatic progression of these tumours.

Adenocarcinoma↗