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Biomedical subjects

N Velasco

Publications and source records attributed to N Velasco.

At least 19 recordsLinked to original sources
PubMed2004

Antineutrophil cytoplasmic antibody-associated necrotizing crescentic glomerulonephritis in a patient receiving treatment with etanercept for severe rheumatoid arthritis.

Etanercept is a tumor necrosis factor inhibitor used in the treatment of rheumatoid arthritis and, increasingly, in a range of other diseases. We report a case of necrotizing crescentic glomerulonephritis, associated with a positive antineutrophil cytoplasmic antibody, causing acute renal failure in a woman receiving treatment with etanercept for severe rheumatoid arthritis. Our patient was treated with steroids and cyclophosphamide following withdrawal of etanercept, with a good clinical response. Although reports of vasculitis in patients receiving treatment with etanercept are rare, this drug has been shown to up-regulate some aspects of immune function, and the possibility that this agent may precipitate or exacerbate vasculitis in some individuals has to be considered.

Adult↗
PubMed2001

[Prevalence of calorie protein malnutrition among patients in chronic hemodialysis].

BACKGROUND: Malnutrition has been strongly associated with morbidity and mortality in hemodialysis patients. In the other hand, dialysis allows a nutritional improvement in patients with more than 12 months in dialysis. AIM: To study the prevalence of malnutrition among patients in hemodialysis. PATIENTS AND METHODS: We measured clinical, anthropometric and biochemical parameters of nutritional status in chronic hemodialysed patients. Results were related to individual time in dialysis. Patients with more and less than 12 months in dialysis were compared. RESULTS: Twenty nine patients (18 male) aged 14 to 65 years old, were studied. Mean caloric intake was 23.8 Cal/Kg and protein intake was 0.7 g/Kg. Mean body mass index was 21.7 +/- 3.7 kg/m2 Thirty eight percent of patients had a body mass index of less than 20 kg/m2. Mean serum albumin was 4.1 +/- 0.7 g/L; mean prealbumin was 33.5 +/- 7.9 mg% and creatinine was 9.6 +/- 2.8 mg%. Serum cholesterol was 182 mg% and triacylglycerol 129 mg%. PCR was 42.2 +/- 18.8 and Kt/V was 1.45 +/- 0.3. We did not find a correlation between nutritional markers and time in dialysis or a difference in nutritional parameters between patients with less or more than 12 months in dialysis. CONCLUSIONS: These patients in chronic dialysis have a high prevalence of caloric malnutrition, which may be due to a poor caloric intake. Protein malnutrition parameters were normal in most patients. The absence of abnormal lipid levels, common in chronic renal failure, is noticeable.

Adolescent↗
PubMed2000

[Academic performance of medical students: a predictable result?].

BACKGROUND: Traditionally, medical schools demand their students a high dedication in time, responsibility and integrity. AIM: To assess the predictive capacity of several specific variables, on the academic performance of medical students. MATERIAL AND METHODS: All students who entered during 1984-1995 period were studied. The academic performance was assessed using two indices: an overall evaluation of successfulness as determined by the approval rate in different courses and grade-point average obtained during the first three years at the Medical School. The variables used to predict academic performance were year of enrollment, high school grades, university admission test scores, biomedical and demographic characteristics. All these were measured at the time when the student was enrolled. RESULTS: Eight hundred and eight students were studied at the end of the third year. The most important predictive variables selected for both performance indices were: high school grades, admission biology test scores, place were high school studies were done, and previous university studies. In addition verbal and mathematics admission academic performance tests scores were selected for grade-point average index. Although, the overall admission score and high school academic performance were significantly associated with the two outcomes, they were not selected in the final models. CONCLUSIONS: The best predictors of an optimal academic performance in these medical students were high school grades, admission biology test scores, residing in Metropolitan Santiago and previous university studies.

Adolescent↗
PubMed1999

Gut mucosal atrophy after a short enteral fasting period in critically ill patients.

PURPOSE: The purpose of this study was to evaluate the presence of gut mucosal atrophy and changes in mucosal permeability in critically ill patients after a short fasting period. MATERIALS AND METHODS: Fifteen critically ill patients underwent a period of enteral fasting of at least 4 days (mean 7.8 days). We took the following measurements the day before initiating enteral nutrition: indirect calorimetry, serum albumin, prealbumin, and lymphocyte count. We also performed a duodenal endoscopic biopsy with histopathological and mucosal morphometric analysis including villus height and crypt depth. The lactulose-mannitol test was performed to assess gut permeability. A total of 28 healthy volunteers served as controls for duodenal biopsy or lactulose-mannitol test. Clinical data, such as length of fasting, severity score, and previous parenteral nutritional support, were recorded. RESULTS: We found gut mucosal atrophy, expressed as a decrease in villus height and crypt depth, in patients compared with controls. The patients also exhibited an abnormal lactulose-mannitol test. Morphometric changes did not correlate with permeability. Further, we found no correlation between the results of the lactulose-mannitol test and of mucosal morphometry with clinical data. CONCLUSIONS: We found that a short period of enteral fasting was associated with significant duodenal mucosal atrophy and abnormal gut permeability in critically ill patients.

Adult↗
PubMed1999

[Transcranial cytokine gradient and intestinal permeability in acute severe brain injury].

BACKGROUND: Acute brain injury is associated with a bimodal hypermetabolic state probably caused by cytokine secretion and high hormone and catecholamine concentrations. In a first stage, the brain would produce these substances and afterwards, another production source, most probably the splanchnic territory, would perpetuate the hypermetabolic state. AIM: To investigate the cytokine production source and to assess intestinal permeability in acute brain injury in the absence of cerebral ischemia and systemic oxygen deficit. PATIENTS AND METHODS: Arterial systemic and cerebral venous bulbar interleukin 1 beta and interleukin 6 levels were measured during the first seven days of evolution in 15 patients with acute brain injury. Serum lactate, the oxygen/lactate ratio, gastric intramucosal pH and intestinal permeability using the lactulose/mannitol test were also assessed in the same period. RESULTS: High arterial and venous interleukin 1 beta and interleukin 6 levels were detected. A positive gradient for interleukin 6 levels was detected throughout the study period with normal intramucosal pH, lactate and oxygen/lactate ratio. There was also an early impairment of intestinal permeability in these patients. CONCLUSIONS: High arterial and venous cytokine concentrations were detected in patients with acute brain injury. The positive gradient for interleukin 6 suggests a brain origin for this cytokine. Intestinal permeability is also altered in these patients.

Adult↗
PubMed1997

[Undergraduate curriculum reform at the Pontifical Catholic University Medical School: aims, methodology and advance status].

The Medical School of the Pontifical Catholic University is devoted to a reform process aiming to adequate undergraduate training to scientific, technological, cultural and social changes in medical practice in Chile and to incorporate novel teaching methodology. One of the main modifications is the change of the resulting professional from "a general physician capable of resolving most medical problems of rural or urban populations" to "a physician with a solid general training but qualified for a subsequent specialization". This requires curricular flexibility to obtain different professional profiles. Other important changes are a reduction in curricular contents and their vertical and horizontal integration, modernization of teaching methodologies with the incorporation of computing techniques and problem oriented teaching and the incorporation of new subjects such as molecular biology, clinical genetics, health economics. To achieve these objectives, a semi-flexible curriculum was devised, the curricular mesh has been modified extensively, an outpatient and a nine months elective internship were added. Most modifications have been implemented, remaining changes in 4th and 5th years. These changes required a reorganisation of academic structure, the use of new selection, training and perfecting criteria for teachers, better salaries for outstanding professors and improvement of teaching infrastructure. This reform must be seen as a medium term integral change in the context of an integral academic development plan.

Chile↗
PubMed1997

[Diabetic neuropathy: thermal sensation and metabolic control in non-insulin-dependent diabetics].

BACKGROUND: The early detection of peripheral neuropathy in diabetics is important since it is the main risk factor for lower limb trophic lesions in diabetics. AIM: To assess the relationship between feet thermal sensation threshold and metabolic control in ambulatory non-insulin-dependent diabetics. PATIENTS AND METHODS: A random sample of 34 non-insulin-dependent diabetics followed for more than five years in a special clinic, out of 368 patients, was selected. Warmth sensation thresholds were measured in the dorsum of both feet using a MSTP-III thermostimulator. The average value of all glycosylated hemoglobins obtained during the 9.7 +/- 5.3 years of follow up for each patient was calculated. A multiple stepwise regression analysis was performed between thermal sensation as the dependent variable and glycosylated hemoglobin, fasting blood glucose, age and diabetes duration. RESULTS: The regression model disclosed glycosylated hemoglobin as the only independent predictor of warmth sensation threshold (partial r = 0.385; p = 0.043). Fifteen diabetic patients with good metabolic control, defined as those with a mean glycosylated hemoglobin of less than 9.5%, had a warmth sensation threshold of 35.6 +/- 3.7 degrees C, whereas 19 diabetics with a had control (glycosylated hemoglobin > or = 9.5%) had a threshold of 39 +/- 3.8 degrees C (p = 0.017). CONCLUSIONS: In this group of diabetics, there is a relationship between the severity of distal polyneuropathy and the metabolic control, assessed with glycosylated hemoglobin levels.

Aged↗
PubMed1995

[Anorexigenic drugs in the treatment of obesity].

Obesity is highly prevalent and has several adverse effects on health. Its treatment is thus warranted and must aim to modify dietary and physical activity habits. The opinion of this association is that anorexigenic drugs with cathecolaminergic action (diethylpropion, phentermine, mazindol and phenylpropanolamine) or serotoninergic action (fenfluoramine and fluoxetine) may be used in moderate or severe obesity (BMI > 30 kg/m2) after a complete clinical assessment and in the context of an integral medical treatment. This association recommends a close surveillance of the use of these drugs, specially when formulated as non-proprietary prescriptions.

Appetite Depressants↗
PubMed1994

[Variability of measured energy expenditure in patients with acute pancreatitis: is it possible to obtain a reliable pathology factor for these cases?].

Energy expenditure was measured in 55 patients with acute pancreatitis, during variable periods ranging from 1 to 5 weeks and it was compared with estimated energy expenditure according to Harris Benedict equations. Patients with severe pancreatitis had similar measured and measured/estimated energy expenditure rations, compared to those with mild pancreatitis (1678 +/- 349.6 kcal/day and 1.1 +/- 0.19 vs 1632 +/- 383 kcal/day and 1.06 +/- 0.19). There was a high dispersion of measured/estimated rations (0.67 - 1.7) that precluded the calculation of a reliable energy expenditure correction factor for this disease. It is concluded that energy expenditure must be measured and not estimated, when planning an adequate nutritional support in patients with acute pancreatitis.

Acute Disease↗