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S Muñoz

Publications and source records attributed to S Muñoz.

At least 73 records · Page 4Linked to original sources
PubMed1992

Characterization of Chilean, Bolivian, and Argentinian Trypanosoma cruzi populations by restriction endonuclease and isoenzyme analysis.

Ninety-one Chilean, 15 Bolivian, and 9 Argentinian Trypanosoma cruzi stocks, isolated from various hosts and vectors, were characterized by schizodeme analysis with EcoRI and MspI endonucleases. The three major similar pattern groups that emerged from this sample correlated with results of isoenzyme analysis. This result confirms previous work and supports the hypothesis of the clonal structure of natural populations of T. cruzi, fully defined at the level of isoenzyme analysis, quantitative kinetoplast DNA restriction fragment length polymorphism, and kinetoplast DNA hybridization analysis. In Chile, sylvatic and domestic cycles of T. cruzi transmission appear to be mainly independent: genetically different families of natural clones are specific to these cycles. Nevertheless, the possibility of overlap remains unclear. Results described here indicate that natural clones inhabiting Chilean regions appear genetically related to the natural clones identified in neighboring countries. In Chile the more frequently sampled parasite types are natural clone 39 and a genetically closely related clone NP13. In this work an evaluation of T. cruzi natural clone mixtures in T. cruzi stocks from Chile was performed for the first time by schizodeme analysis before and after serial transfer in mouse maintenance. The results indicate that six of nine stocks are composed of two or more natural clones. This observation raises the relevant question of whether specific T. cruzi natural clones generate different clinical features of Chagas' disease.

Animals↗
PubMed1992

Production and characterization of a monoclonal antibody against the ribosome inactivating protein alpha sarcin.

In order to improve the purification of immunoconjugates containing alpha sarcin, a ribosome-inactivating protein, and in the attempt to define the enzymic region of the toxin, MAbs against alpha sarcin were produced. From 5 fusions, by adopting a short period of immunization and very low doses of the immunogen, 10 anti-toxin-producing clones were obtained. One of them, named MAsg2 (IgG2b), due to its specific reactivity and secreting properties, was selected for further characterization. MAsg2 was found to recognize an epitope which is common to two, i.e. alpha sarcin and clavatin, of the three different aspergillins tested, but is not involved in the active site of the toxins.

Animals↗
PubMed1991

Evidence of absence of Trypanosoma cruzi kinetoplast DNA methylation by restriction endonuclease analysis.

Eight kinetoplast DNA samples from very different T. cruzi zymodemes were digested with the isoschizomer group of enzymes (MspI-HpaII) and (MboI-Sau 3AI), able to detect DNA methylation on cytidine and adenine for the CCGG and GATC sequences, respectively. Restriction digestion analysis of each kDNA with both isoschizomer groups of enzymes did not display a different profile suggesting that maxicircles and minicircles on this trypanosomatid are not methylated.

Animals↗
PubMed1990

[Morphological and functional parameters of the left ventricle (mass, wall thickness and end-systolic stress) in school children with different levels of blood pressure, at rest and during maximal exercise].

Echocardiographically determined left ventricular mass, diastolic septal and posterior wall thickness and end-systolic wall stress, as well as electrocardiographic indexes of left ventricular enlargement (Sokolow-Lyon index and Romhilt-Estes score) and of left atrial enlargement (P terminal index) were correlated with resting and exercise systolic and diastolic blood pressures, and with several parameters of body size (weight, height, body surface area, Quetelet index), in 130 school children (61 boys, 69 girls) 6 to 15 years of age. Parameters of body size had a positive correlation both with systolic and diastolic blood pressures and with parameters of left ventricular size. Thus, the latter were adjusted for body surface area, for correlation with blood pressure. Left ventricular mass and diastolic septal and posterior wall thickness had a very poor correlation with resting and exercise diastolic blood pressures. Left ventricular mass and diastolic posterior wall thickness had a significantly higher correlation with peak exercise systolic blood pressure than with resting systolic blood pressure. End-systolic wall stress had a positive correlation with resting diastolic and systolic blood pressures. Electrocardiographic parameters of left ventricular and left atrial enlargement had a very poor correlation with resting and exercise blood pressure. Our findings suggest that early in life left ventricular mass and wall thickness are more closely related to maximal systolic blood pressure during physical exercise than to blood pressure in basal conditions. The electrocardiogram is an insensitive method to detect early modifications of left ventricular size in relation to different levels of blood pressure. The echocardiogram is the method of choice for this purpose.

Adolescent↗
PubMed1989

[Otomycosis: presentation of 15 cases].

Fifteen cases of otomycosis in 11 women and 4 men attending the Clinic Hospital in Salamanca during the period from 1984 to 1988 are discussed. A. niger was the species isolated on the majority of occasions (73.3%). The commonest form of presentation of otomycosis was simple chronic (73.3%). The clinical pictures was characterized by serous secretion and pruritus. Otomycosis with associated bacterial infection (20.0%) was the cause of the most intense symptoms, featuring suppuration and hypoacusia. In 5 patients, local antecedents of interest were observed: three cases of chronic cholesteatomatose otitis in which surgery had been performed; retroauricular eczema, and perichondritis of the ear. Despite topical treatment with clotrimazole, 4 cases of relapse occurred (26.7%) and in none of these was associated bacterial infection observed.

Adult↗
PubMed1986

Utilization of alpha-ketoisocaproate for synthesis of hepatic export proteins and peripheral proteins in normal and cirrhotic subjects.

The ratio R, defined as (percent of dose of 14C)/(percent of dose of 3H) in the leucine of plasma fibrinogen, albumin, immunoglobulin G (IgG), red cell globin, and salivary mucin, was measured in 7 normal adults and in 5 cirrhotic patients during continuous intragastric infusion of 1-14C-labeled alpha-ketoisocaproate (KIC) and 3H-labeled leucine. The ratio R measured in whole body protein has been shown in rat experiments to be a measure of the nutritional efficiency of KIC relative to leucine. In normal subjects, R in albumin and fibrinogen became constant (0.63 +/- 0.05) after the third hour and were indistinguishable from one another. The ratio R in IgG was similar and constant. The ratio R in plasma leucine (0.62 +/- 0.06) was significantly lower than R in mucin (0.86 +/- 0.04) or globin (0.73 +/- 0.04), indicating that these latter proteins derive a significant fraction of their leucine from KIC transaminated locally, rather than from circulating leucine. Results in 5 cirrhotic patients were the same, except that R in IgG and R in globin were significantly increased. Thus, cirrhosis does not alter the efficiency, relative to leucine, with which oral KIC is used for synthesis of export proteins by the liver, but increases the efficiency with which it is used for the synthesis of some proteins peripherally.

Adult↗
PubMed1984

Two-dimensional contrast echocardiography with carbon dioxide in the detection of congenital cardiac shunts.

Medically pure (100%) carbon dioxide directly injected into a peripheral vein was used for 2-dimensional contrast echocardiography in 134 patients with an arteriovenous shunt demonstrated by cardiac catheterization and cineangiography, Qp/Qs ratios of 1.5 to 3.7, pulmonary-to-systemic peak systolic pressure ratios of 0.2 to 0.8 and no oximetrically demonstrable venoarterial shunt. Two patients with transposition of the great arteries, intact ventricular septum and a Senning operation as well as 30 normal subjects of comparable age also were studied. In patients with an atrial septal defect, the gas microbubbles opacified the left atrium. In patients with a ventricular septal defect, the gas microbubbles opacified the left ventricle, whereas the left atrium was free of contrast. In all patients with patent ductus arteriosus, the gas microbubbles opacified the abdominal aorta, whereas the left atrium, left ventricle, aortic root and aortic arch remained free of contrast. In 2 patients in whom an aneurysm of the sinus of Valsalva ruptured into the right ventricle, the "negative" contrast effect permitted localization of the shunt. In 2 patients with transposition of the great arteries, an intact ventricular septum and a Senning operation, the intracardiac flow pattern was clearly demonstrated. No complication was observed. We conclude that pure carbon dioxide directly injected into a peripheral vein is a safe and advantageous echocardiographic contrast material. Because of its greater diffusibility in comparison with oxygen and fluid contrast media, small venoarterial shunting can be detected in defects such as atrial septal defect, ventricular septal defect and patent ductus arteriosus, in which only an arteriovenous shunt can be demonstrated by oximetry.

Adolescent↗
PubMed1981

Serum cholesterol and triglyceride levels in school-age population. Distribution, correlation, and prevalence of high values.

The distribution of serum cholesterol and triglycerides, the prevalence of high values, and their correlations with other variables were studied in a sample of the school population of Caracas, Venezuela, 6 to 15 years of age (1,385 boys and 1,412 girls). The mean serum cholesterol level was 156.36 mg/dL in girls and 153.10 mg/dL in boys, remaining stable during the whole age range in both sexes. Mean serum triglyceride level was significantly higher in girls than in boys. In girls, mean serum triglyceride level increased uniformly with age between ages 6 and 15 years, whereas in boys it remained stable after age 9 years. Serum cholesterol levels above 160 mg/dL were observed in 43.9% of the girls and in 38.2% of the boys. Our findings suggest that the association of serum cholesterol and triglyceride levels with weight mainly reflects the adipose tissue component of body weight.

Adolescent↗
PubMed1980

Blood pressure in a school-age population. Distribution, correlations, and prevalence of elevated values.

Distribution of blood pressure values, prevalence of levels potentially predictive of hypertension in adulthood, and correlations with othe variables were studied in a sample of 2,809 children (1,392 boys and 1,417 girls) 6 to 15 years of age in Caracas, Venezuela. The mean values of systolic and diastolic blood pressures increased steadily with age in both sexes and were significantly higher in girls. The prevalence of high blood pressure readings was 10.2%-7.0% in boys and 13.3% in girls, a significant differnce. It was significantly higher in obese (7.6%) than in nonobese (3.8%) children. No significant differences in blood pressures were found among 1,580 mestizo, white, and black children. Partial correlation studies showed a determinant influence of weight in the correlation of blood pressure with height; the correlation with weight remained high after removal of the influence of height and age. At repeat examination 12 to 18 months later, 36% of the children who had a high blood pressure reading continued to have high values. Fifty-eight percent of them had one or both parents or one or more siblings (or both) who had hypertension.

Adolescent↗
PubMed1975

Influence of surgery on the natural history of rheumatic mitral and aortic valve disease.

The rate of survival, the evolution of functional cardiac status and the incidence of major complications during a 5 year period were studied in 410 patients with rheumatic mitral or aortic valve disease, of whom 200 were treated medically and 210 by surgery. The 5 year survival rates in patients with various types of rheumatic mitral valve disease were similar (45 percent for those with mitral stenosis and 46 percent for those with mitral insufficiency or mixed mitral insufficiency and stenosis). The survival rate in patients with aortic valve disease was somewhat more favorable (64 percent). Mitral valvulotomy had the most positive influence on mortality. The 85 percent 5 year survival rate of patients who underwent this procedure was significantly higher than that of patients with medically treated mitral stenosis. In patients submitted to mitral and aortic valve replacement, the survival rate was also improved in comparison with data in the corresponding medically treated group, but to a lesser degree (70 percent for aortic valve replacement and 60 percent for mitral valve replacement). In all surgically treated groups, initial operative mortality was the primary determinant of the rate of survival at the end of 5 years. Survivors of all surgical groups had appreciable improvement in cardiac functional classification and a remarkable reduction in the incidence of heart failure and atrial fibrillation. The incidence of infectious endocarditis was significantly reduced after mitral valvulotomy, as compared with the incidence in patients with medically treated mitral stenosis. Mitral and aortic valve replacement did not reduce the incidence of infectious endocarditis. The incidence of thromboembolic phenomena was favorably influenced by mitral valvulotomy and aortic valve replacement, but not by mitral valve replacement.

Adolescent↗