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C Vargas

Publications and source records attributed to C Vargas.

At least 91 records · Page 5Linked to original sources
PubMed1984

Normal reference-intervals for 20 biochemical variables in healthy infants, children, and adolescents.

We determined normal reference values from data on sera of 2099 outpatient children (ages one week to 14 years) at our institution. Using a continuous-flow instrument (SMAC, Technicon), we determined the following analytes in each serum sample: glucose, creatinine, uric acid, inorganic phosphorus, sodium, potassium, chloride, total CO2, iron, cholesterol, triglycerides, total protein, albumin, total bilirubin, creatine kinase, lactate dehydrogenase, alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, and calcium. The resulting data were coded and subsequently processed in an IBM 370 computer, and the reference values (3rd and 97th percentiles) were defined for each analyte. A two-way analysis of variance was also done to determine the influence of age and sex on results of these 20 biochemical tests.

Adolescent↗
PubMed1981

Hypothenar hammer syndrome.

The hypothenar hammer syndrome is a distinct entity of digital ischemia caused by the repetitive compression of the distal ulnar artery against the hook of the hamate. Definite diagnosis should most likely rely on selective arteriography. Primary resection with anastomosis and cervicodorsal sympathectomy have both been proposed as treatment. Early recognition of the syndrome is important.

Brachial Artery↗
PubMed1980

Polyacrylamide gel electrophoresis in human serum proteins in "normal" individuals and cancer patients.

The electrophoretic pattern of serum proteins of 100 "normal" adults and 97 non treated patients bearing different types of neoplasias were comparatively studied in polyacrylamide gel to find out if there are specific proteins or protein patterns in cancer. Densitometry was used to complete the study so as to analyze quantitative differences for each one of the regions of the arbitrarily divided electrophoregram of both types of sera. Strictly standardized colorimetric technique was used to quantify total proteins. Protein nomenclature was taken from literature data. As an average we found more bands in the cancer bearing patients than in "normal" individuals that also showed greater colour affinity in proteins. In the different regions, the main feature of neoplasia case was the presence of fewer bands in the post albumin (PA) and alpha-beta (post-beta) zones and many in 7s-globulin region (7s-g) than those found in "normals". The most important changes in the electrophoretic pattern of cancer patient serum were: a) Decrease in prealbumin (Pa), albumin (Alb), some from the postalbumin region (PA) and transferrin (T); frequent absence of ceruloplasmin (Cer) and complement factor 3 (C3) in a reduced number of cases. b) Marked increase of one alpha 1 glycoprotein in the PA region, hemopexin, haptoglobins and alpha 2-macroglobulin. Densitometry was useful to improve data obtained from visual analysis of gels but it could not make a quantitative differentiation of changes observed in beta and 7s-g regions. There was no significant difference in total protein concentration. Advantages and limitations of this method are discussed and results obtained are analyzed.

Adolescent↗
PubMed1979

Significance of phosphatidylglycerol in amniotic fluid in complicated pregnancies.

In normal pregnancy lecithin/sphingomyelin ratios correlate with gestational age. In complicated pregnancies biochemical maturation of fetal lung may be accelerated or delayed, depending upon maternal, fetal, or placental conditions. Surfactant contains other phospholipids besides lecithin, including phosphatidylglycerol (PG), the second major component of mature surfactant. Ninety phospholipid patterns in amniotic fluid were studied by two-dimensional thin-layer chromatography. In uncomplicated pregnancies PG was absent until 37 weeks' gestation, then increased there after. In complicated pregnancies (pre-eclampsia, diabetes Classes D, F, and R, premature rupture of membranes) PG was identified before 35 (as early as 29 weeks' gestation. These results verify accelerated lung maturation in certain complicated pregnancies. No newborn infant developed respiratory distress syndrome in the presence of PG.

Amniocentesis↗
PubMed1976

Correlation between leuteinizing hormone responses to luteinizing hormone-releasing hormone (LH-RH) and to D-leu-6-LH-RH-ethylamide in patients with hypothalamo-pituitary disease.

Seventeen patients (eleven females and six males) with organic hypothalamo-pituitary disease were subjected to a test consisting of a rapid intravenous injection of 50 mug of luteinizing hormone-releasing hormone (LH-RH) at 8:00 A.M., with blood sampling before and 30 and 60 minutes afterward. Two to four weeks later, a rapid intravenous injection of 50 mug of D-Leu-6-des-Gly-10-LH-RH-ethylamide (D-Leu-6-LH-RH-EA) was given under similar conditions, with blood sampling before and 30, 60, and 90 minutes afterward. Serum LH levels were determined by radioimmunoassay. D-Leu-6-LH-RH-EA caused a greater and more sustained rise in serum LH levels than did an equal dose of LH-RH. However, functional classifications of patients were similar with either preparation. This finding suggests that acute administration of D-Leu-6-LH-RH-EA does not cause a higher number of relevant responses as compared with LH-RH, but only a greater stimulation of LH releases in responsive patients.

Adenoma, Acidophil↗
PubMedDate not supplied

Transposable elements as mutator genes in evolution.

Strains of the bacterium Escherichia coli harbouring genes that increase mutation rates are known to have an evolutionary advantage in chemostat competition over otherwise isogeneic strains with lower mutation rates. This advantage is frequency-dependent, the mutator strain being favoured only above a starting ratio of approximately 5 x 10(-5), and it results from the fact that the necessary beneficial mutations cannot be generated in a mutator population below a certain size. Here we consider the possibility that the mutagenic properties of transposable elements confer an advantage in the same manner as mutator genes. A previous report has shown that the transposon Tn5 increases the fitness of E. coli in chemostats, although the reason for this effect has not been established. Our results show that the transposon Tn10 also confers an advantage in chemostats. In addition, we find that (1) this advantage, like that associated with mutator genes, is frequency-dependent, (2) whenever the Tn10 strains win, a segment of Tn10, probably its IS10 sequences, has undergone transposition to a new site, (3) the new insertions converge into a site contained within a 3.2 kilobase (kb) PvuII fragment of the genome, and (4) no transpositions are detected when the Tn10 population loses. We conclude that Tn10 confers an advantage by increasing the mutation rate of the host bacterium.

Biological Evolution↗