Search PubMed⌕ Search

Biomedical subjects

C Vargas

Publications and source records attributed to C Vargas.

102 records · Page 6Linked to original sources
PubMedDate not supplied

Differences in foetal heart rate variability from phonocardiography and abdominal electrocardiography.

The agreement of the phonocardiographic method to provide foetal heart rate variability (FHRV) indices equivalent to those derived from abdominal electrocardiography was tested. 15 pregnant women were recruited in order to obtain antepartum foetal phonocardiograms and abdominal electrocardiograms three minutes long. From the respective sound (SS) and electric (RR) time series, typical temporal and spectral indices of FHRV were computed and compared. Means of the SS and RR intervals were not significant (P> 0.05) and these showed a correlation r=0.98. However, the temporal indices, P(TOT), HF and LF/HF presented differences (P< 0.05), since SS values were higher. Spectral coherence decreased below 0.5 for frequencies above 0.28+ 0.07 Hz, where bands resembling maternal and foetal breathing movements were noted. Particularly above 0.28Hz, temporal and spectral FHRV indices derived from phonocardiography and electrocardiography show differences. Quality of the signal, processing techniques, and maternal and foetal respiratory factors could account to explain these.

Adult↗
PubMedDate not supplied

Cerebrospinal fluid nitrate levels in patients with Parkinson's disease.

It has been suggested that nitric oxide could be implicated in the neuronal degeneration of substantia nigra compacta in patients with Parkinson's disease. Recently, it has been reported decreased CSF nitrate levels (oxidation product that provides an indirect estimation of nitric oxide) in Parkinson's disease patients, assessed with a colorimetric method. We studied the CSF and plasma levels of nitrate with a kinetic cadmium-reduction method in 31 Parkinson's disease patients and 38 matched controls. The CSF and plasma nitrate levels were not correlated either in patient or in the control group, and they did not differ significantly between the two study groups. They were not influenced significantly by antiparkinsonian drugs in patients, although there was a trend for CSF nitrate levels to be higher in patients treated with levodopa or with dopamine agonists. CSF and plasma nitrate levels did not correlate with age at onset, duration, scores of the unified Parkinson's disease rating scales and Hoehn & Yahr staging in the patients group. These date suggest that CSF and plasma levels of nitrate are apparently unrelated with the risk for PD.

Blood-Brain Barrier↗
PubMedDate not supplied

Prognostic value of cytosolic p53 protein in breast cancer.

The prognostic value of cytosolic p53 protein was evaluated in 458 operable breast carcinomas by immunoblotting using the monoclonal antibody PAb 1801. Two hundred and five carcinomas (45%) showed positive p53 accumulation and 55% were p53 negative. When comparing p53 positivity and other clinicopathological parameters, significant differences were found with younger age (p = 0.017), premenopausal status (p = 0.003), increasing tumor size (p = 0.026), negative estrogen receptor (p = 0.003) and negative progesterone receptor (p = 0.047), but not with histologic grade, axillary lymph node status, stage or erbB-2 expression. With a median follow-up of 34 months (range 3-70), relapse has occurred in 73 patients. Disease-free survival curves showed that patients with p53-positive tumors had a significantly shorter disease-free survival than patients with p53-negative carcinomas (log-rank test, p = 0.027). A multivariate analysis of disease-free survival showed that p53, tumor size, histologic grade and progesterone receptor had significant independent prognostic value. The immunoblotting technique was controlled with p53 immunohistochemistry in 94 paired samples. We obtained a statistically significant correlation (p = 0.0004) between the two methods. Our results show that the immunoblotting technique offers an alternative approach in evaluating the p53 status of breast biopsy material using cytosolic extracts, and confirm that p53 accumulation is a significant independent indicator of a poor prognosis in operable breast carcinoma.

Adult↗
PubMedDate not supplied

Epidemiology of aortic aneurysms: I. Mortality trends in the United States, 1951 to 1981.

The trends in mortality from aortic aneurysms in the United States from 1951 through 1981 were studied. Annual age-specific and age-adjusted mortality for aortic aneurysms were calculated for white males, white females, nonwhite males, and nonwhite females. For all four groups, a constant increase in age-adjusted mortality was noted for the period 1951 to 1968 (an average annual increase of 17% for white males, 12% for white females, 14% for nonwhite males, and 15% for nonwhite females), plateauing in 1968, with a slight decline noted after 1968. The increase corresponded to an increase in the total number of U.S. aortic aneurysm deaths from about 2500 to approximately 14,000. The decline was most notable for dissecting aneurysms. Analysis of the age-specific rates by birth cohort suggests that mortality is increasing with each subsequent cohort. Analysis of specific aneurysm types (dissecting, thoracic, abdominal, and not otherwise specified) suggests that abdominal ones are most common. These data are reviewed in the context of existing knowledge of aortic aneurysms. Further studies to validate these findings and to develop hypotheses for the etiology of aortic aneurysms are needed.

Adult↗
PubMedDate not supplied

Deflazacort increases laminin expression and myogenic repair, and induces early persistent functional gain in mdx mouse muscular dystrophy.

Deflazacort slows the progress of Duchenne muscular dystrophy (DMD) with fewer side effects than prednisone. In mdx mice, deflazacort treatment augments repair and growth of new muscle fibers. We tested the hypothesis that deflazacort improves muscle function and promotes repair by increasing myogenic cell proliferation and fiber differentiation. mdx mice (3.5 weeks old) were treated with deflazacort (1.2 mg/kg) or vehicle for 4 weeks. Forelimb grip strength was measured. After 4 weeks, the right tibialis anterior muscle (TA) was crush injured to induce synchronous regeneration. DNA was labeled using different markers 24 and 2 h before collecting tissues 4 days after injury. The expression of creatine kinase (CK) isoforms, laminin-2 (merosin) mRNA and protein, and proliferation by myogenic cells were measured and satellite cells were identified by immunolocalization of c-met receptor. Peak grip strength increased 15% within 10 days of treatment, and was maintained up to 6 weeks after the end of treatment in a second experiment. Expression of CK MM in the regenerating TA rose from 46% to 55% of total CK activity after deflazacort treatment. Satellite cells were more numerous and appeared earlier on new fibers, in concert with a threefold increase in proliferation by myogenin+ (but not MyoD+) myoblasts. alpha2-Laminin mRNA expression and protein increased 1.3-5.5-fold relative to MM CK in regenerating and dystrophic TA, respectively. These studies support the hypothesis that deflazacort promotes functional gains, myogenic differentiation, myoblast fusion, and laminin expression in regenerating dystrophic muscle. The potential to augment precursor specification, strength, and possible membrane stability may be useful in directing long-term benefits for DMD patients and short-term amplification of precursors prior to myoblast transfer.

Animals↗
PubMedDate not supplied

[Gastroduodenal Crohn's disease - report of 4 cases and review of the literature].

BACKGROUND: Crohn's disease can affect all the gastrointestinal tract, but gastroduodenal involvement is rarely seen (0.5 to 13%). OBJECTIVES: Report clinical, radiological and endoscopic findings and treatment of four patients with gastroduodenal Crohn's disease and review the literature. PATIENTS AND METHODS: Four patients (one male of 24 years old three females of 37, 66 and 74 years old) with epigastric pain, weight loss and low grade fever were referred to the University Hospitals of Federal University of Rio de Janeiro and Fluminese Federal University. Two had also mild intermittent diarrhea and arthritis/arthralgia and the third developed pyloric obstruction and received surgical treatment. Anemia was observed in only one (the young female). Barium x-ray studies showed aphthous ulcers in stomach and duodenum with distal ileum lesions and deformity in both. Upper gastrointestinal endoscopy revealed aphthous ulcers in stomach and geographic duodenal ulcers. Polypoid lesions and serpiginous ulcers within gastric antrum were observed in the young female. Colonoscopy was performed in two patients and disclosed an ulcerated ileitis in one and ulcerated pancolitis in other. Histopathology findings of biopsy specimens were inconclusive (granulomas were not found) and other causes of granulomatous disease were ruled out. Corticosteroids and proton pump inhibitors were started and two patients had their disease controlled. The other patient developed pyloric obstruction and had to be operated. CONCLUSIONS: Gastroduodenal Crohn's disease has distinct clinical, therapeutic and prognostic features. Advances in endoscopic methods and recognition of new histopathologic criteria for diagnosis have revealed an incidence higher than previously reported.

Adult↗
PubMedDate not supplied

[Management of a case of maple syrup urine disease--the use of gluco-insulinotherapy].

We report here the treatment and poor outcome of a case of Maple Syrup Urine Disease with late diagnosis and retrieval (2 and 5 months, respectively). As the proband had quite high levels of plasmatic leucine (1956 micromol/L for a normal upper limit of 77), we started immediately with a gluco-insulin therapy to produce anabolism in the infant. When leucine has fallen to 275.3 micromol/L, we instituted feeding with branched chain amino acid-free protein and high energy from carbohydrates. After reviewing briefly the clinical, biochemical and therapeutic aspects of this disorder, we comment on the great difficulties of making early diagnosis and of obtaining the specific dietetic formulas to Maple Syrup Urine Disease, in Brazil.

English Abstract↗
PubMedDate not supplied

[Arthroplasty in congenital aortic coarctation in adults with balloon and endovascular prosthesis: immediate results and 6-month follow-up].

Up to 1982, surgery was the treatment of aortic coarctation, with postsurgical recoarctation in 39% of cases. Since 1984 balloon aortoplasty has been performed successfully in adolescents and adult patients. We present the immediate results, and more than six months follow up of 6 patients with congenital aortic coarctation, who underwent this procedure. Five of the six patients were male, with an average age of 28.6 years (15-46), and in 4 of them a stent was placed. Systolic pressure of ascending aorta decreased from 187.1 mm of Hg (+/- 41.8) to 128 (+/- 25.4), and transaortic gradient from 66 mm of Hg (+/- 21.8) to 4.8 (+/- 7.6). Coarctation luminal diameter increased from 4.6 mm (+/- 1.41) to 14.3 (+/- 3) in patients with only balloon aortoplasty and to 17.8 mm with stent placement, p = NS. Angiography in three patients with stent at 6 months did not reveal restenosis, all six patients require less antihypertensive medications. Acute and chronic complications, percentage and time of restenosis, long term results, and possible benefit of stents are yet to be determined.

Adolescent↗
PubMedDate not supplied

[Immediate results in percutaneous mitral valvuloplasty with the Nucleus balloon].

UNLABELLED: We present the immediate results of mitral valvuloplasty in 10 patients using Nucleus balloon. Several publications show highly successful results obtained with the Inoue balloon and double balloon technique. There are no publications of Nucleus balloon. We consider that this device could offer several advantages according to its physical and technical characteristics. We performed the procedure in 10 female patients, with severe mitral valve stenosis, with an average age of 44.8 years (23-70) and an average Wilkins score of 7.5 (6-9), using a combined technique. The increase in mitral valve area with Gorlin equation was 1.03 +/- .13 to 2.6 +/- .67 cm2, the decrease in transmitral gradient from 15 +/- 4.1 to 3.42 +/- 2.6 mm Hg, and decrease in systolic pulmonary pressure from 54.1 +/- 18.8 to 24.9 +/- 5.1 mm Hg. One patient developed grade I mitral insufficiency after the procedure, and another non significant interatrial shunt. CONCLUSIONS: Good results are obtained with this balloon, the valvuloplasty technique is more simple than with double balloon, it is much cheaper than Inoue balloon and we consider it could be useful in moderately calcified valves.

Adult↗
PubMedDate not supplied

[Direct fetal electrocardiography].

The advancement in bioelectronics applied to medicine has made possible to carry out, with a high degree of fidelity, the study of the electrical events of the fetal heart. One of the methods in use is the direct or internal method, which offers the advantage of enabling the clear recognition of the different phases of the electrocardiogram, even during labor. An analysis of some parameters of the direct fetal electrocardiogram was carried on in normal term fetuses and whose mothers were in good health, and the parturition was normal. The parameters studied were: heart rate, P-R interval duration, the P wave, the QRS complex, the ventricular activation time, the P-R segment behaviour, intraventricular conduction, and RS-T and T wave changes. The first five items were submitted to statistical analysis for the calculation of the mean value, standard deviation and standard error. The practical application of the results is discussed in terms of deductive approach to the direct fetal electrocardiogram. It is concluded that the method is valuable for the prompt recognition of fetal distress mainly during labor.

Electrocardiography↗