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C Barrientos

Publications and source records attributed to C Barrientos.

10 recordsLinked to original sources
PubMed2001

(AC)n dinucleotide repeat polymorphism in 5' beta-globin gene in native and Mestizo Mexican populations.

Repeated sequences are dispersed along the human genome. These sequences are useful as markers in diagnosis of inherited diseases, in forensic medicine, and in tracking the origin and evolution of human populations. The (AC)n repeated element is the most frequent in the human genome. In this paper, the (AC)n repeated element located in the 5' flanking region of the beta-globin gene was studied by single-strand conformation polymorphism (SSCP). Four ethnic Mexican groups (Mixteca, Nahua, Otomí, Purépecha) and a Mestizo population were analyzed. We observed three alleles, A [(AC)16, B [(AC)14], and C [(AC)18], with a frequency of between 68.2% and 86.9%, 13.1% and 18.2%, and 6.7% and 13.7%, respectively. Allele C was present only in Purépecha and Mestizo groups. The absence of this allele in the other ethnic groups studied suggests that there is low genetic admixture of Purépecha and that this is a relatively isolated population. However, it could be that the C allele occurs in low frequencies in the other groups as a result of small sample sizes. The (AC)n repeat polymorphism in the beta-globin gene has not been previously studied in Amerindian populations.

Alleles↗
PubMed1995

Molecular studies of Mendelian disorders, embryonic neoplasias, and polymorphisms in selected samples of the general population. A contribution to the genetic characterization of the Mexican population.

Molecular studies using polymerase chain reaction (PCR) and restriction enzymes, as well as intragenic STRs and newly designed primers, were performed in patients with Duchenne-Becker muscular dystrophy, sickle cell anemia, retinoblastoma, and nephroblastoma. The usefulness of these methodologies in the precise identification of mutational changes, in carrier detection and in the understanding of neoplastic transformations, as well as its applications in genetic counseling and prenatal diagnosis, are discussed. In addition, genetic polymorphisms in the beta globin gene cluster and in mtDNA were investigated. All these studies, the first performed in our population, contribute to establish the genetic origin and to a better characterization of the Mexican population.

Adolescent↗
PubMed1993

Effects of diabetes on disposition and hepatic handling of cefmetazole in rats.

1. The effects of streptozotocin-induced diabetes on disposition and hepatic handling of cefmetazole, a broad-spectrum cephalosporin, were investigated in rats. 2. Male Wistar rats were pretreated with streptozotocin (60 mg/kg, i.p.) to induce uncontrolled diabetes. Fourteen days later bile flow was significantly reduced (12%) and bile acid secretion was significantly enhanced (87%) when compared with control animals. 3. Following intravenous injection of cefmetazole at a dose of 200 mumol/kg, maximal and cumulative biliary excretion of the antibiotic were significantly impaired in streptozotocin-treated animals (27 and 22%, respectively). 4. Cefmetazole excretion into bile was accompanied by marked choleresis. The magnitude of bile flow increase was larger in control animals. 5. Total systemic clearance of the antibiotic was reduced (36%) and mean half-life for the fast and slow phases of disposition increased (136 and 48%, respectively) in diabetic rats. 6. These changes were probably due to the diabetic condition of the animals because insulin treatment resulted in almost complete correction.

Animals↗
PubMed1993

[Hemodynamic and functional hepatic effects of isosorbide-5-monitrate in cirrhotic patients with portal hypertension].

Isosorbide 5-mononitrate reduces portal pressure in acute conditions. The aim of this work was to assess its effects and tolerance development after 30 days of use in alcoholic cirrhotic patients without history of variceal bleeding. Nine patients with portal hypertension (7 with esophageal varices) were studied. Hepatic and systemic hemodynamic parameters were measured in basal conditions, after one hour and after 30 days of treatment (40 mg b i d). One patient was lost from control at 2 weeks. In the total group, portal pressure decreased from 15.1 +/- 3.7 mm Hg to 12.1 +/- 5 at one hour and 11.3 +/- 5.5 mm Hg at 30 days (p < 0.002). In two patients, portal pressure was not modified. Portal blood flow increased significantly at one hour in the 7 responder patients. Hepatic blood flow (indocyanine green clearance) was not modified; thus, estimated hepatic resistance decreases in both periods. Intrinsic indocyanine green clearance (a measure of hepatic function) did not change in any period. Systemic blood pressure decreased and cardiac rate increased only after one hour. The fall in portal pressure did not correlate with changes in portal or hepatic blood flow. It is concluded that isosorbide 5-mononitrate decreased portal pressure in 7 out of nine patients, even after 30 days of treatment, without untoward effects over hepatic function or perfusion.

Adult↗
PubMed1992

[Fatal infectious endocarditis in a patient with annulo-aortic ectasia and predominant bicuspid valve aortic stenosis. Anatomoclinical case].

A 25 year old female with bicuspid aortic valve and aortic stenosis developed infectious endocarditis due to beta hemolytic streptococcus. Specific antibiotic therapy was not successful, the patient developed multiple embolic episodes and platelet dysfunction that prevented surgery. The patient died 5 weeks after admission. Necropsy showed aortic annulo-ectasia, cystic medial necrosis and localized dissection of the proximal aorta. There were multiple aortic valve vegetations and evidence of inflammatory myocardial involvement, coronary embolization and myocardial infarction. Aortic annulo-ectasia should be investigated in patients with aortic valve endocarditis and early surgery would be advised to prevent aortic dissection.

Adult↗
PubMedDate not supplied

Subjective global assessment of nutritional status: further validation.

Subject global assessment of nutritional status was performed on 175 patients admitted to the medical-surgical gastroenterology service of a general hospital by a first-year resident and a specialist in clinical nutrition who were not aware of each other's evaluation. Patients were classified as well nourished or moderately or severely undernourished. Simultaneously, anthropometry was performed, serum albumin measured, and two units of PPD inoculated. A 79% concordance between the global subjective assessments made by the residents and the specialists was found. Patients in the three groups had significantly different weight, midarm circumference, triceps skinfold, and serum albumin values, whereas the total lymphocyte count and the percentage of negative PPD reactions were not significantly different. Subjective global assessment is a useful tool for the evaluation of nutritional status, even when used by inexperienced professionals.

Anthropometry↗