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C Muñoz

Publications and source records attributed to C Muñoz.

At least 109 records · Page 6Linked to original sources
PubMed1996

Transcriptional up-regulation of intracellular adhesion molecule-1 in human endothelial cells by the antioxidant pyrrolidine dithiocarbamate involves the activation of activating protein-1.

The redox status of the cell plays an essential role in regulating signal transduction, transcription factor activity, and expression of cell surface molecules. In this study, we show that pyrrolidine dithiocarbamate (PDTC), a potent antioxidant agent, upregulated the cell surface expression of intercellular adhesion molecule-1 (ICAM-1) in human endothelial cells (EC). Further analysis of PDTC-mediated ICAM-1 up-regulation revealed that PDTC increased ICAM-1 mRNA levels and augmented its gene promoter activity. Transfection experiments in EC with reporter constructs harboring nested deletion fragments of the ICAM-1 promoter indicated the presence of a functional PDTC-responsive region located between positions -136 to -353 of the promoter. Gel retardation assays together with supershift analysis revealed that PDTC induced the binding of c-fos and c-jun to a consensus activating protein-1 (AP-1) binding site located at position -284. PDTC alone or in combination with TNF-alpha enhanced AP-1-dependent transactivation in HUVEC, as determined by DNA binding assays. The functional implication of AP-1 in the transcription of the ICAM-1 gene was further demonstrated by cotransfection experiments in which a c-jun expression vector induced the promoter activity of the PDTC-responsive element of the ICAM-1 promoter. Taken together, these results indicate that the antioxidant PDTC induces transcriptional activation of ICAM-1 and that this induction is mediated at least in part by the transcription factor AP-1. This mechanism might be operative in pathologic conditions in which a redox imbalance plays a key role, such as ischemia/reperfusion injury or arteriosclerosis.

Antioxidants↗
PubMed1996

Pentosan polysulfate-induced thrombocytopenia: a case diagnosed with an ELISA test used for heparin-induced thrombocytopenia.

We report a patient who developed severe thrombocytopenia and ischemic stroke following pentosan polysulfate treatment. An ELISA test employed in type-II heparin-induced thrombocytopenia was highly positive. To our knowledge, this is the first case in which this test has been performed in a pentosan polysulfate-induced thrombocytopenia (PIT). Our data suggest that the antibody against pentosan polysulfate-platelet complex also cross-reacts with heparin-platelet factor 4 complex. Due to its greater sensitivity and wider availability, this ELISA test should be used in cases where PIT is suspected.

Cross Reactions↗
PubMed1996

Cluster headache syndrome associated with middle cerebral artery arteriovenous malformation.

Cluster headache (CH) is an idiopathic cephalalgic syndrome, although several pathological processes have been described in association with this syndrome. We report two cases of cluster headache in hospitalized patients with middle cerebral artery dependent arteriovenous malformation (AVM). After surgical removal of the AVM the headache completely resolved, suggesting that complementary studies and treatment of the underlying aetiology may be indicated for secondary forms of cluster headache.

Cerebral Arteries↗
PubMed1996

Interleukin 1 and tumor necrosis factor in obese alcoholics compared with normal-weight patients.

We performed a liver biopsy and measured plasma concentrations of interleukin 1 beta (IL-1 beta) and tumor necrosis factor alpha (TNF-alpha), and spontaneous and lipopolysaccharide-stimulated in vitro monocyte production of IL-1 beta and TNF-alpha in 19 obese and 17 age-matched, normal-weight alcoholics admitted for treatment of their alcoholism. Nine healthy normal-weight alcoholics had cirrhosis in their liver biopsy (Fisher's exact test: P=0.031). A histologic score (derived from the sum of fat, necrosis, fibrosis, and inflammation in the biopsy) correlated with body mass index and the percentage body fat, calculated by using the sum of four skinfold-thickness measures. Plasma concentrations and spontaneous in vitro monocyte production of IL-1 beta and TNF-alpha were below detection limits. No significant differences were observed between normal-weight and obese alcoholics with or without cirrhosis and normal control subjects in lipopolysaccharide-stimulated monocyte production of IL-1 beta (6.5 +/- 0.8, 10.1 +/- 2.7, 7.9 +/- 1.6, and 5.28 +/- 4.24 micrograms/L, respectively) or TNF-alpha (2.8 +/- 0.4, 3.7 +/- 1.0, 3.0 +/- 0.44, and 1.97 +/- 1.01 micrograms/L, respectively). However, a positive correlation was found between IL-1 beta production and body mass index (r=0.333, P=0.047), percentage body fat (r=0.412, p=0.013), abdominal circumference (r=0.416, P=0.012), and total histologic score (r=0.331, P=0.049). A multiple-regression model accepted abdominal circumference as the only independent predictor of IL-1 beta production. TNF-alpha did not correlate with any of the above-mentioned indexes. We conclude that obese alcoholics have a higher frequency of histologic liver damage and that IL- 1 beta production by stimulated monocytes is related to abdominal fat accumulation.

Adult↗
PubMed1996

Expression of CD15 in normal and metaplastic Paneth cells of the digestive tract.

AIMS: To substantiate that incubation with monoclonal antibody CD15 (C3D-1) elicits a distinctive immunoreaction in normal small intestinal Paneth cells, normal and metaplastic Paneth cells along the digestive tract were assessed to determine whether they are also immunoreactive to CD15. METHODS: Paneth cells in paraffin wax embedded specimens of normal small intestine, appendix and proximal ascending colon, and from cases of chronic gastritis and ulcerative colitis were investigated immunohistochemically for lysozyme and CD15 antigen expression by means of the avidin-biotin peroxidase complex method. RESULTS: CD15 antibody reacted with a high proportion of both normal and metaplastic Paneth cells. Paneth cell immunoreactivity to CD15, however, was less intense and less extensive than to antilysozyme antibody, though the latter also stained many other cell types and was more commonly associated with nonspecific background staining. CONCLUSIONS: CD15 seems to be a valuable adjuvant for the study of Paneth cells in the normal and diseased digestive tract. Furthermore, as CD15 has been shown to be involved in activation of phagocytes, its expression in Paneth cells reinforces their proposed role as antimicrobial agents and regulators of the intestinal flora.

Appendix↗
PubMed1996

[Cerebral toxoplasmosis in patients with human immunodeficiency virus (HIV) infection. Clinico-radiological and therapeutic aspects in 63 patients].

We have retrospectively reviewed 63 cases of encephalic toxoplasmosis (ET) in HIV-infected patients in order to determine clinical and radiological characteristics, the diagnostic value of serologic determinations, and the response to antioxoplasmic therapy. ET was the AIDS-defining condition in 44% of the patients. Eighty of the patients had a CD4 cell count < 100/microliters when ET was diagnosed. Only 4.8% of the patients had been taking anti-Pneumocytis carinii prophylaxis with cotrimoxazol. The most frequent clinical presentation was focal neurologic signs in 80.9% of the patients, with headache and fever in 53.3% and 42.4%, respectively. The most frequent cerebral CT finding was hipodense lesions (92%) with ring enhancement (68.9%). They were most frequently had a hemisferic location. Seroconversion was detected in two patients (6%), whereas 55 patients had serologic evidence of latent infection by Toxoplasma gondii (87.3%). Ninety eight percent of the patients were treated with sulphadiazine plus pyrimethamine. However, such therapy should be discontinued in 22% of them and switched to clindamycin plus pyrimethamine. The overall mortality rate during the acute phase of the disease was 7.9%, but 41.4% of the survivors exhibited neurologic sequelae. Relapsing ET was detected in 33.3% of the patients, and it was usually due to discontinuation of treatment. The mean survival time after the diagnosis of ET was 11.5 months. ET is the most common opportunistic infection of the central nervous system among our AIDS patients. Primary prophylaxis for toxoplasmic infection seems advisable in our epidemiologic environment, when CD4 cell count is less than 200/microliters and there is serologic evidence of latent infection. Acute ET usually has a good response to therapy, and the acute mortality rate is low. However, most of the survivors will remain with neurologic sequelae. The high frequency of adverse effects to sulphamide therapy with clindamycin make the need of alternative treatment strategies urgent.

Acquired Immunodeficiency Syndrome↗
PubMed1996

[Microbiological study of the respiratory tract in children with cystic fibrosis].

PURPOSE: Pulmonary infections is a main cause of morbimortality in patients suffering from cystic fibrosis. The objective of this study was to know the flora implicated in respiratory pathology of all mucoviscidotic children attending Hospital Sant Joan de Déu of Barcelona. METHODS: Quantitative cultures from respiratory samples (most of them: sputum) of 26 patients were performed from January 91 to June 93. There were 13 girls and 13 boys, aged 1 to 13 years (mean: 7 years). RESULTS: 282 microorganisms were isolated from 203 positive samples. Cultures of 88.4% of patients yielded in some moment Haemophilus influenzae, 82.6% of them Haemophilus parainfluenzae, 65.3% Pseudomonas aeruginosa, 50% Streptococcus pneumoniae, 38.4% Staphylococcus aureus. The most prevalent microorganism was P. aeruginosa (66%) followed by H. influenzae (29%) and S. aureus (26.6%). 59% of P. aeruginosa strains showed a mucoid phenotype. CONCLUSIONS: Haemophilus sp. causes short term infections that affect children of all ages, whereas infections due to P. aeruginosa persist in spite of correct antimicrobial therapy.

Adolescent↗
PubMed1995

Immune depression induced by protein calorie malnutrition can be suppressed by lesioning central noradrenaline systems.

Depressed immune function is well documented in protein calorie malnutrition (PCM). Also, central noradrenergic hyperactivity has recently been reported in malnourished animals. Increase in central noradrenaline activity could be responsible for cell-mediated immune depression. The present study is designed to address this hypothesis by testing whether neurotoxic lesion of central noradrenergic systems by 6-hydroxydopamine (6-OHDA) could improve lymphoproliferative response to mitogens and interleukin (IL)-1 production in PCM rats. A significant enhancement of lymphoproliferative response to concanavalin A (ConA) and in IL-1 production was observed in spleen mononuclear cells of PCM rats injected intracerebroventricularly with 120 micrograms of 6-OHDA, as compared with solvent injected and untreated PCM animals. A significant decrease in brain noradrenaline levels was produced in the drug-injected animals. These results suggest that central noradrenergic hyperactivity is one of the mechanisms involved in the immunodepression produced by malnutrition.

Animals↗
PubMed1995

Abnormal polymerization and normal binding of plasminogen and t-PA in three new dysfibrinogenaemias: Barcelona III and IV (gamma Arg 275-->His) and Villajoyosa (gamma Arg 275-->Cys).

Congenital dysfibrinogenaemia was found in three non-related patients. None of them had a haemorrhagic tendency, but one gave a thrombotic history. When their fibrinogens were treated with thrombin, they released fibrinopeptides A and B at normal rates, but the resultant fibrin monomers produced exhibited abnormal polymerization curves. This abnormality was more marked in fibrinogen Villajoyosa than in Barcelonas III and IV. Plasminogen and t-PA binding to fibrin monomers from the three dysfibrinogenaemias was similar to that of normal fibrin monomers. The gamma chain was purified from the three fibrinogens, treated with CNBr and the peptides produced were separated by reversed-phase HPLC. Chromatograms of digested fibrinogens showed an abnormal peak that was not present in the normal gamma chain. Amino acid sequence analysis of abnormal peptides and genomic DNA sequencing revealed that the gamma arginine 275 had been changed in the three fibrinogens; in two cases it was substituted by histidine, and in the third by cysteine. The altered properties observed in fibrin monomers produced from fibrinogen with the gamma Arg 275-->His or gamma Arg 275-->Cys substitution, suggests that this amino acid is important in maintaining the protein structure necessary for normal polymerization, but is not essential for the binding of t-PA or plasminogen to fibrin. It also suggests that the change Arg-->Cys produces more severe alterations in the functions of fibrinogen than the substitution Arg-->His.

Adult↗
PubMed1995

Detection and characterization by immunoblot analysis of potentially diagnostic Leishmania infantum polypeptides in human visceral leishmaniasis.

Humoral immune responses were studied in 53 sera from 18 patients with visceral leishmaniasis by immunoblot analysis. Sera from visceral leishmaniasis patients recognized antigens with molecular weights ranging from < 14 kDa to more than 100 kDa. Bands ranging between 49 and < 14 kDa were the most specific. The 40, 33 and 17 kDa antigens were recognized by 90%, 79% and 79% of the patients sera, respectively. Sera from one patient with Chagas' disease identified 8 of 11 antigens of the specific region. Treatment with periodate eliminated the cross-reaction in three of these antigens (40, 29, 26 kDa). The study of serial sera collected from the different patients showed a decrease in intensity or dissappearance in some of the diagnostic bands, particularly the 17 kDa band. The band of 17 kDa seems to be useful to study the clinical evolution, for post-treatment control and also for epidemiologic purposes. (It has been identified in 7% of control sera from endemic areas.) Immunoblot could be a valuable tool in the diagnosis of visceral leishmaniasis, being more sensitive and specific than other serologic tests.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Immunological aspects of a case of posttransplant lymphoproliferative disorder.

We describe a female renal transplant recipient with cytomegalovirus and Epstein-Barr virus (EBV) infections who developed aggressive polymorphous polyclonal B cell proliferation. She received two courses of OKT3. We found a majority of transformed B cells bearing EBV membrane receptor CR2 and EBV nuclear antigen. Posttransplant lymphoproliferative disorders may be associated with a significant immunological activation, detected in this case by the sudden increase of beta 2-microglobulin and immunoglobulin levels, including immunoglobulin D. These raised levels persisted throughout the short and rapid course of the disease.

Adult↗
PubMed1995

Glucose and insulin tolerance tests in the rat on different days of gestation.

To study insulin/glucose relationship during gestation, rats were studied on days 6, 12, 15, 18, 20 or 21 of pregnancy and the results were compared to values in sex-matched virgin control rats. Blood glucose levels were decreased on days 20 and 21 of gestation whereas plasma insulin levels appeared decreased on days 6 and 12, unchanged on day 15 and enhanced on days 18, 20 and 21 of gestation. Total pancreas insulin content was already augmented on day 6 of gestation and continued to increase with gestational time. With the exception of an increase in the 6-day-pregnant rats 22.5 min after an oral glucose load, blood glucose levels did not differ between 6- or 12-day-pregnant rats and virgin controls although plasma insulin levels reached higher values on these days. However, in the 15-day-pregnant rats, glucose tolerance after the glucose load was enhanced while plasma insulin levels did not differ from those in virgin rats during the first 30 min. In the 18-day-pregnant rat blood glucose was more increased but plasma insulin did not differ after the glucose load when compared to virgin rats, whereas 20- or 21-day-pregnant rats showed a glucose tolerance similar to that of virgin rats but their insulin levels shortly after the glucose load were higher. The hypoglycemic response to a high intravenous dose of insulin was decreased in 12-, 18-, 20- and 21-day-pregnant rats. Therefore, whereas in both the 6- and 12-day-pregnant rats there is an enhanced beta-cell response to the glucose insulinotropic effect and insulin responsiveness is reduced in 12-day-pregnant rats, the 15-day pregnant rat is in a transitory stage where both insulin sensitivity and the beta-cell response return to nonpregnant values. However, from 18 days of gestation on, there is an intense insulin-resistant condition which is only partially compensated by an enormous accumulation of insulin in the pancreas followed by a faster and larger insulin release after a glucose load.

Animals↗
PubMed1995

Prevention of in vitro neutrophil-endothelial attachment through shedding of L-selectin by nonsteroidal antiinflammatory drugs.

The activation of the endothelial cells by extravascular stimuli is the key event in the extravasation of circulating leukocytes to target tissues. L-selectin, a member of the selectin family, is constitutively expressed by white cells, and is the molecule involved in the initial binding of leukocytes to activated endothelium. After activation, leukocytes rapidly release L-selectin from the cell surface, suggesting that the functional activity of this molecule is controlled in large part by its appearance and disappearance from cell surface. We have studied in a neutrophil-activated endothelial cell binding assay, the effect of different antiinflammatory drugs (steroidal and nonsteroidal) in the L-selectin-mediated interaction of neutrophils with activated endothelial cells. Some nonsteroidal antiinflammatory drugs (NSAIDs), such as indomethacin, diclofenac, ketoprofen, and aspirin, but not steroids, strongly inhibited the neutrophil-endothelial cell attachment. Furthermore, we also investigated the underlying mechanism of this functional effect. The expression of L-selectin on the neutrophil surface rapidly decreased in the presence of different NSAIDs, in a dose- and time-dependent manner, whereas no changes in the expression of other adhesion molecules such as CD11a, CD11b, CD31, or ICAM-3 (CD50) were observed. Interestingly, studies in vivo on healthy volunteers treated with physiological doses of indomethacin showed a significant decrease of L-selectin neutrophil expression. Only diclofenac induced an upregulation of CD11b expression, suggesting an activating effect on neutrophils. No enzyme release was observed upon treatment of neutrophils with different NSAIDs, indicating a lack of degranulatory activity of NSAIDs, with the exception of diclofenac. The downregulation of L-selectin expression was due to the rapid cleavage and shedding of the membrane L-selectin, as determined by both immunoprecipitation from 125I-labeled neutrophils, and quantitative estimation in cell-free supernatants. These results suggest that NSAIDs exert a specific action on adhesion receptor expression in neutrophils, which might account, at least in part, for the antiinflammatory activities of NSAIDs.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1995

Lymphangioma of Vater's ampulla: a rare cause of obstructive jaundice. Endoscopic therapy.

BACKGROUND: We report endoscopic excision of a lymphangioma in an infrequent location, Vater's ampulla, with resolution of the obstructive jaundice caused by this tumor. METHODS: An endoscopic papillotomy was performed together with polypectomy of the tumoral mass. RESULTS: The patient evolved satisfactorily, with jaundice and biochemical cholestasis disappearing. CONCLUSIONS: We believe endoscopic therapy is the ideal treatment for small lymphangiomas in the digestive tract.

Aged↗