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M Ortiz

Publications and source records attributed to M Ortiz.

At least 37 records · Page 2Linked to original sources
PubMed2002

[Minimal-change disease with mesangial IgA deposits associated with Sjogren syndrome].

Sjögren's syndrome may be accompanied by a dysregulation of IgA system implying the presence of increased serum polymeric IgA or circulating immune complexes and their consequent deposition within the kidney. In this context IgA nephropathy may only represent one of the complications brought by IgA deposition. Glomerular involvement and primary Sjögren's syndrome has been described previously only in isolated case reports, membranous nephropathy and membranoproliferative glomerulonephritis have been reported. We have not found any case of minimal change disease and glomerular IgA deposition associated with Sjögren's syndrome. In this patient nephrotic syndrome was related to serum increase of CA 19-9; this association has been reported in only three previous cases.

Adrenal Cortex Hormones↗
PubMed2001

Detection of growth factor receptor RNA in individual hematopoietic cells by in situ RT-PCR; comparison with RT-PCR.

The ability to detect changes in RNA expression in single cells would greatly enhance understanding of the molecular basis of biological responses to positive and negative growth regulators. To this end, we compared expression of RNA encoding the receptors for interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-6, leukemia inhibitory factor (LIF) and stem cell factor (SCF) in populations of primitive hematopoietic progenitors (lineage marker negative, Lin(-), and Lin(-) c-Kit(+)) by RT-PCR and in situ RT-PCR. Both Lin(-) and Lin(-) c-Kit(+) progenitors expressed all receptors by RT-PCR. However, RT-PCR could not distinguish between the possibility that all cells expressed growth factor receptor RNA, or the possibility that only a proportion of cells expressed RNA. Therefore, we used in situ RT-PCR to examine growth factor receptor mRNA expression in individual cells. In contrast to RT-PCR, we observed that only 40-80% of Lin(-) cells and 75-100% of Lin(-) c-Kit(+) cells were positive for expression of the growth factor receptor subunits, demonstrating that not all cells were receptor positive. We found that in situ RT-PCR could also be used to measure induction or repression of receptor RNA expression in these cell populations. Specifically, the percentage of cells expressing IL-6alpha receptor RNA decreased from 88% positive in freshly harvested cells to 9% in Lin(-) c-Kit(+) cells cultured in IL-3 for 18 h. Thus, in situ RT-PCR can be used to detect and quantify the number of individual cells that express growth factor receptor mRNA, and may also be useful to measure changes in expression of other endogenous genes or genes introduced by transfection and gene therapy vectors.

Actins↗
PubMed2001

[Tumors diagnosed in 65 patients with type I neurofibromatosis].

BACKGROUND: Type 1 neurofibromatosis patients develop malignant neoplasm more frequently than general population. PATIENTS AND METHOD: We have studied 65 patients with neurofibromatosis type 1 because we intend to know the kind of neoplasms that they have presented. RESULTS: 65 patients (48 men and 17 women) fulfilling type 1 neurofibromatosis criteria have been studied. Globally 67 tumors appeared, from which 47 (70%) were benign and 20 (30%) were malignant. Benign tumors included 25 neurofibromas, 11 central nervous system tumors and 11 extraneurological tumors. Malignant tumors accounted for 6 soft tissue sarcomas, 6 carcinomas, 3 malignant CNS tumors and 2 acute lymphoblastic leukemias. CONCLUSION: Presentation of neoplasms is frequent in type 1 neurofibromatosis and constitutes main death and morbility cause.

Aged↗
PubMed2001

HIV type 1 non-B subtype prevalence in Spain, 1997-1998.

We have evaluated the prevalence of HIV-1 non-B subtypes in Spain by means of an enzyme immunoassay (EIA) for discrimination between B and non-B subtypes. Samples were obtained from newly diagnosed patients attended at internal medicine outpatient clinics between October 1997 and October 1998. Discrimination between HIV-1 B and non-B subtypes was carried out by means of the EIA, with V3 synthetic peptides specific to the different subtypes. Non-B-serotyped samples were genetically analyzed in the gp41 region from the original sera. During the study period, 909 samples were collected from 21 medical units located in various Spanish geographical regions. Serotyping was possible in 885 cases, of which 791 were assigned as B serotype (89.38%), 70 showed no reactivity to any of the peptides (7.91%), and the remaining samples displayed other reaction patterns (2.72%). Of the 94 non-B-assigned samples, 65 were genetically characterized in the gp41 region of the env gene: 55 were B subtype, 5 were A subtype (4 clustered with CRF02AG reference strains), 3 were C subtype, and 2 were G subtype. The prevalence rate for non-B subtypes in Spain was established at 1.13% (95% CI, 0.59-2.21). Although the B subtype is predominant in the Spanish population, other subtypes have been detected.

Enzyme-Linked Immunosorbent Assay↗
PubMed2001

Panic disorder in a Spanish sample of 89 patients with pure alcohol dependence.

High rates of anxiety disorders, including panic disorder (PD), have been found in patients suffering from alcohol dependence (AD). It has been suggested that alcoholic subjects with PD represent a more severe subgroup of patients. Eighty-nine patients with 'pure' AD (without abuse of other drugs) were examined and compared for the presence of PD. Several clinical scales were administered to assess symptomatology and severity. Twenty-three patients (25.8%) met the criteria for PD. The mean age at onset for alcohol use was 18.7 versus 28.5 years for PD onset. Our finding of an earlier onset for alcoholism than for PD in a sample of Spanish patients illustrates the potential importance of transcultural factors. These patients were more likely to be women and to have first-degree relatives with PD. Overall, alcoholic patients with comorbid PD showed greater clinical severity. They were found to have more comorbidity with axis I disorders (major depression and dysthymia), greater clinical severity, and a history of more suicide attempts.

Adult↗
PubMed2001

Molecular epidemiology of HIV type 1 subtypes in equatorial guinea.

Equatorial Guinea is endemic for HIV-1. This country borders to the north with Cameroon, where different subtypes belonging to group M, as well as group O strains, are circulating simultaneously. To assess the molecular epidemiology of HIV-1 in Equatorial Guinea we analyzed 76 plasma samples collected throughout 1999 from seropositive individuals. Phylogenetic analysis of the gp41 region revealed that 53 were of subtype A, with 64% of these sequences clustering with CRF02_AG reference strains; 11 were of subtype C; 4 were of subtype D; 2 (closely related to subtype F2) were of subtype F; 3 were of subtype G, two of them forming a separate cluster with the recombinant circulating forms CRF06_cpx; 1 was of subtype H; and 2 were unclassifiable. Although subtype A is predominant, the presence of 14% of subtype C is also noteworthy. This work represents the first HIV-1 subtype distribution study in Equatorial Guinea.

Base Sequence↗
PubMed2001

Determinants of inducibility of ventricular tachycardia.

We analyzed the incidence and predictive factors for induction of clinical ventricular tachycardia (VT) during an electrophysiologic study in 127 patients with structural heart disease and spontaneous VT documented by 12-lead electrocardiography. Eighty-five patients had coronary artery disease (CAD), 24 had idiopathic dilated cardiomyopathy (IDC), and 18 had right ventricular dysplasia (RVD). Clinical variables were age, gender, electrocardiographic patterns of spontaneous arrhythmia, cardiac diagnosis, left ventricular (LV) ejection fraction (EF), infarct location, and presence of LV aneurysm. Clinical VT was induced in 76 patients (60%, group 1) and was not induced in 51 patients (group 2). Clinical VT was induced in 83% of patients with RVD, 58% of patients with CAD, and 50% of patients with IDC (p = 0.07). LVEF tended to be significantly higher in group 1 than in group 2 (p = 0.06). The presence of left QRS axis in the frontal plane during spontaneous VT was significantly associated with a higher inducibility both in the general group (69% vs 46%, p <0.02) and in patients with CAD (70% vs 44%, p <0.02). In patients with CAD, only the presence of a left QRS axis was significantly associated with a higher inducibility. A multivariate analysis identified only the left QRS axis as a significant and independent predictor of induction of clinical VT. The association of a leftward axis with inducibility suggests that vectorial factors in the depolarization wavefronts may be related to inducibility since conventional stimulation is performed from the right ventricle, producing a leftward axis in most cases.

Adult↗
PubMed2001

Effect of angiotensin-converting enzyme inhibition on renal filtration surface area in hypertensive rats.

BACKGROUND: Angiotensin-converting enzyme (ACE) inhibitor treatment leads to protective effects on the cellular structure of the glomerulus and the kidney. The aim of this study was to determine whether ACE inhibition increases renal filtration surface area in the spontaneously hypertensive rat (SHR). METHODS: SHR were treated with the ACE inhibitor perindopril at a high dose (3 mg/kg/day) or a low dose (0.1 mg/kg/day) during the period of hypertension development, from 7 to 14 weeks of age. Some animals were treated concomitantly with the bradykinin B2 receptor antagonist, S16118. Tail-cuff systolic blood pressure and body weights were measured twice weekly. At termination of treatment, glomerular number and volume, length, and surface area of glomerular capillaries and renal filtration surface area were estimated using unbiased stereological techniques. RESULTS: There were significant dose-related reductions in blood pressure with high- and low-dose perindopril treatment. Neither low- nor high-dose perindopril treatment had any effect on glomerular number or size or glomerular capillary length and surface area. Hence, there was no significant difference in total renal filtration surface area between any of the experimental groups (8721 +/- 610 mm2 in untreated SHR and 7879 +/- 338 mm2 and 8767 +/- 437 mm2 in the low and high dose perindopril-treated groups, respectively). Coadministration of the bradykinin antagonist did not affect any of the glomerular parameters. CONCLUSIONS: ACE inhibition during the period of hypertension development does not lead to an enhanced glomerular capillary growth or increases in total renal filtration surface area in this model.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2001

Histological evaluation of immune organs in chicken embryos inoculated with Marek's disease virus and lymphokines.

The aim of the present study was to evaluate the presence of lymphocytes and granulocytes in different stages of embryonic development and on the first posthatching day. The lymphocytes present in the bursa of Fabricius and thymus were evaluated by histological analysis of the yolk sac, bursa of Fabricius, thymus, liver and bone marrow of 100 chicken embryos divided into groups and treated with: (I) Marek's disease vaccine as viral antigen, (II) Marek's disease vaccine plus lymphokines, (III) lymphokines, and (IV) vaccine diluent. Group V was not treated. Samples were taken on days 14, 17 and 20 of incubation and on the first posthatching day. An increase in the number of epithelial matrix as precursors of lymphoid follicles was observed in the bursa of Fabricius of embryos inoculated with lymphokines compared to embryos in all the other groups (p < 0.05). In addition, a higher amount of granulocytes was found in the yolk sac and liver of embryos inoculated with lymphokines than in the embryos of all other groups (p < 0.05). In the bone marrow, no significant difference was observed among the treated groups concerning the amount of granulocytes. The results suggest that administration of antigens or protein molecules at an early stage of embryonic development increases the presence of granulocytes in the liver and granulopoiesis in the yolk sac, and also increases the number of epithelial matrixs in the bursa of Fabricius.

Animals↗
PubMed2001

[A new species of amphipod crustacean of the genus Amphilochus (Crustacea, Amphipoda, Amphilochidae) from Venezuela].

A new species of amphipod Crustacea (Gammaridea, Amphilochidae) of the genus Amphilochus Bate, 1862, is described. The species was collected in Phallusia nigra (Savigny, 1816) at depths between 0 and 2 m, in the pier piles of the Marina El Ancla and Los Manglares gas station in Morrocoy National Park (Falcón State, Venezuela), during the months of June and July 1998. The main differences between A. ascidicola new species and all others species of the genus recorded from the Gulf of Mexico and the Caribbean Sea, are given.

Animals↗