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E Ramos

Publications and source records attributed to E Ramos.

At least 91 records · Page 5Linked to original sources
PubMed1999

[CMACPAR an modified parallel neuro-controller for control processes].

CMACPAR is a Parallel Neurocontroller oriented to real time systems as for example Control Processes. Its characteristics are mainly a fast learning algorithm, a reduced number of calculations, great generalization capacity, local learning and intrinsic parallelism. This type of neurocontroller is used in real time applications required by refineries, hydroelectric centers, factories, etc. In this work we present the analysis and the parallel implementation of a modified scheme of the Cerebellar Model CMAC for the n-dimensional space projection using a mean granularity parallel neurocontroller. The proposed memory management allows for a significant memory reduction in training time and required memory size.

Algorithms↗
PubMed1998

Dearomatization of Antioxidant Rosemary Extracts by Treatment with Supercritical Carbon Dioxide.

Treatment with supercritical CO(2) is proposed for deodorizing antioxidant rosemary extracts obtained by steam distillation and Soxhlet extraction. The process conditions have been optimized by applying a Taguchi experimental design with the aim of obtaining, at minimum cost, a product with acceptable antioxidant activity as well as minimum rosemary aroma. Variables were selected for their effects on the selective extraction of the compounds responsible for the residual aroma of the rosemary extract. The optimized method allowed 90% dearomatization; no detrimental effects in antioxidant activity or color of the extracts have been observed after supercritical fluid processing.

Journal Article↗
PubMed1998

Field studies and cost-effectiveness analysis of vaccination with Gavac against the cattle tick Boophilus microplus.

The control of tick infestations and the transmission of tick-borne diseases remains a challenge for the cattle industry in tropical and subtropical areas of the world. Traditional control methods have been only partially successful and the parasites continue to result in significant losses for the cattle industry. Recently, vaccines containing the recombinant Boophilus microplus gut antigen Bm86 have been developed. These vaccines have been shown to control tick infestations in the field. However, extensive field studies investigating the efficacy and cost-effectiveness of vaccination have not been reported and are needed to appraise the effect of this new approach for tick control. Here is reported the results of the application of Gavac in a field trial including more than 260,000 animals in Cuba. In this study the correlation between the antibody response to vaccination and the effect on ticks fertility is determined. Physiological status of the animals was found to affect the primary response to vaccination but not the antibody titers after revaccination. A cost-effectiveness analysis showed a 60% reduction in the number acaricide treatments, together with the control of tick infestations and transmission of babesiosis, which resulted in savings of $23.4 animal-1 year-1. These results clearly demonstrate the advantage of vaccination and support the application of Gavac for tick control.

Animals↗
PubMed1998

Plasma and mucosal fatty acid pattern in colectomized ulcerative colitis patients.

Patients with inflammatory bowel disease (IBD) have increased plasma n3 polyunsaturated fatty acids (PUFAs), which in ulcerative colitis (UC) patients persists six months after colectomy, suggesting a primary abnormality in fatty acid (FA) metabolism in IBD. This finding needed to be confirmed in a larger series of UC long-term colectomized patients. We aimed to assess the plasma FA pattern in UC colectomized patients with either Brooke's ileostomy (UC-BI) or ileal pouch anal anastomosis (UC-IPAA) and the mucosal FA pattern in the ileal reservoir of the UC-IPAA patients. Plasma FAs were assessed in 63 UC colectomized patients (31 with BI and 32 with IPAA) and 30 controls. In 26 UC-IPAA (8 with pouchitis and 18 without pouchitis) and in 13 healthy controls gut mucosal FAs were also investigated. FAs were detected by capillary column gas-liquid chromatography. Increased levels of saturated fatty acids (SFAs) and decreased percentages of monounsaturated fatty acids (MUFAs) were observed in both groups of patients. There were no changes in plasma n3 and n6 PUFAs. The mucosal FA pattern of the ileal reservoir consisted of increased long-chain PUFAs, specially n6 PUFA, and a decrease of their essential precursors. High percentages of SFAs and low percentages of MUFAs were also seen. The plasma FA profile previously described in IBD is not observed long-term after colectomy in UC, suggesting that it is related with the presence of inflamed intestine. High concentrations of SFAs and decreased percentages of MUFAs might represent early events in disturbed FA metabolism in IBD. The changes in FAs of the ileal reservoir, which closely resemble those found in human and experimental IBD, probably represent a common pattern of intestinal inflammation.

Adult↗
PubMed1998

Muscle strength and hormonal levels in adolescents: gender related differences.

The purpose of the present investigation was to study muscle strength in adolescents and its relationship to serum levels of testosterone and growth hormone in both genders. Thirty active adolescents (15 boys; age range 11 -12 y/o) participated in the first study. Isokinetic muscle strength of the dominant knee extensors (KE) was determined at 0, 12, 20, 30, 120, 180 and 240 deg/sec using a Cybex 340 dynamometer. The assessment of pubertal status was accomplished using the criteria of Tanner. Serum levels of total testosterone (T) and growth hormone (GH) were determined using radioimmunoassay techniques. Boys had higher (p< 0.001) T levels but no differences in muscle strength were detected between genders. Fifty-seven additional subjects representing three age groups (11-12 y/o, n=18; 13-14, n=21; 17-18, n=18) participated in the second study. A significant increase in peak torque (absolute and corrected for body weight) with age was observed in both genders. There were no significant gender differences in strength for the two youngest age groups, but boys were stronger than girls in the oldest age group (group 3). Testosterone and GH levels increased with age in boys but not in girls. Gender related differences in T were found in groups 2 and 3. A positive correlation (r=0,64 boys; r=0.46 girls) between testosterone levels and absolute muscle strength was seen in both genders. Our results suggest that increases in anabolic hormones precede muscle strength gains in adolescent males. In addition, gender related differences in muscle strength during adolescents cannot be explained solely on the basis of difference in body size or T levels.

Adolescent↗
PubMed1998

Enhanced responses to Mycobacterium tuberculosis antigens by human alveolar lymphocytes during active pulmonary tuberculosis.

Responses to mycobacterial and nonmycobacterial antigens were examined in bronchoalveolar cells (BAC) and peripheral blood mononuclear cells (PBMC) from patients with active pulmonary tuberculosis (n=16) and healthy subjects (n=23). DNA synthesis in BAC (but not PBMC) from tuberculosis patients was significantly increased in response to the mycobacterial antigens purified protein derivative (PPD), antigen 85, and mannose-capped lipoarabinomannan but not to nonmycobacterial antigens. The response to PPD was also increased in enriched alveolar lymphocytes from tuberculosis patients (P<.05). The frequency of interferon-gamma but not interleukin-4- or -10-producing cells by ELISAspot was increased in PPD-stimulated BAC from patients with tuberculosis (P<.05). Accessory function of alveolar macrophages for T lymphocyte responses was similar and suppressive activity was variably decreased in tuberculosis patients. Thus, there is compartmentalization of mycobacterial antigen-specific lymphocytes to the lungs during active tuberculosis that on challenge produce a Th1-type cytokine host response.

Adolescent↗
PubMed1998

Long-term intake of soy protein improves blood lipid profiles and increases mononuclear cell low-density-lipoprotein receptor messenger RNA in hypercholesterolemic, postmenopausal women.

The long-term clinical effects of soy protein containing various amounts of isoflavones on lipoproteins, mononuclear cell LDL receptor messenger RNA concentrations, and other selected cardiovascular risk factors are not well known. Sixty-six hypercholesterolemic, free-living, postmenopausal women were investigated during a 6-mo parallel-group, double-blind trial with 3 interventions. After a control period of 14 d, all subjects were randomly assigned to 1 of 3 dietary groups (all with 40 g protein): a National Cholesterol Education Program (NCEP) Step 1 diet with protein from casein and nonfat dry milk (control), an NCEP Step 1 diet with protein from isolated soy protein containing moderate amounts of isoflavones (ISP56), or an NCEP Step 1 diet with protein from isolated soy protein containing high amounts of isoflavones (ISP90). Non-HDL cholesterol in both the ISP56 and ISP90 groups was reduced compared with the control group (P < 0.05), whereas total cholesterol was not changed. HDL cholesterol increased in both the ISP56 and ISP90 groups (P < 0.05), whereas the ratio of total to HDL cholesterol decreased significantly in both groups compared with the control (P < 0.05). Mononuclear cell LDL receptor messenger RNA concentrations increased in subjects consuming ISP56 or ISP90 compared with the control (P < 0.05). These results indicate that soy protein, with different amounts of isoflavones, may decrease the risk of cardiovascular disease via improved blood lipid profiles, and that the mechanism by which apolipoprotein B-containing lipoproteins were depressed may be via alterations in LDL receptor quantity or activity.

Aged↗
PubMed1998

[Diet and risk of myocardial infarction. A case-control community-based study].

OBJECTIVE: To evaluate diet as a risk factor for myocardial infarction. DESIGN: Community based case-control study. SETTING: University Hospital, Oporto. PARTICIPANTS: First time consecutive cases of acute myocardial infarction (n = 100) and 198 community controls, older than 39 years and living in Oporto, were compared. METHODS: Data were collected by trained interviewers using a structured questionnaire designed to obtain information on socio-demographic, medical and behavioural aspects, emphasising the description of diet and food habits (using a semi-quantitative food frequency questionnaire). Controls were selected by random digit dialing with a participation rate of 70%. Odds ratios and 95% confidence intervals (CI) according to quartiles of nutrient ingestion were calculated using unconditional logistic regression. RESULTS: Female controls presented significantly higher mean intakes of protein, omega-3 fatty acids, fiber, cholesterol and vitamin C. Male controls had a significantly higher mean daily intake of fiber, vitamin C, vitamin E, and carotenes. After adjusting for age, sex, education, body mass index, ethanol, smoking and total energy intake, there was a protective effect of vitamin C (OR = 0.2, 95% CI: 0.1-0.6, for the 4th quartile), vitamin E (OR = 0.3, 95% CI: 0.1-0.9 for the 4th quartile) and total fiber (OR = 0.3, 95% CI: 0.1-0.9) for the 4th quartile). No significant effect was found for trans-fatty acids, but there was a higher risk with increased energy intake. CONCLUSIONS: This study showed that diet has an important independent effect on myocardial infarction, a protective independent role for anti-oxidant vitamin C and E was verified.

Adult↗
PubMed1998

[Resection as elective treatment of hilar cholangiocarcinoma (Klatskin tumor)].

A retrospective analysis of our experience in the treatment of hiliary cholangiocarcinoma or Klatskin tumor was performed with the aim of evaluating the morbi-mortality and prognosis of its treatment to thereby determine the usefulness of the different therapeutic options. From 1989 to 1997, 51 patients diagnosed with hiliary cholangiocarcinoma were treated in our hospital. Surgery was indicated in 16 with curative aims (group I) while palliative treatment with percutaneous biliary drainage was indicated in 35 (group II). Biliary resection was carried out in 8 patients being associated with hepatic resection in 4 (group IA) and in 8 patients undergoing liver transplantation (group IB). Clinico-epidemiologic data and hospital stay were similar in all the groups. The frequency of complications was similar in groups I and II although the frequency of cholangitis (49%) in group II was noticeable. The percentage of readmissions was also greater in group II (12 vs 46%, respectively; p = 0.03) with prosthesis obstruction being the most frequent cause. Accumulated survival at 1, 2, and 3 years in group I was 84, 64 and 48% with a median survival of 33 months, while in group II the median survival was of 6 months with no patient surviving more than 2 years (p = 0.0001). When groups IA and IB were compared, greater frequency of complications in groups IA (100 vs 37%; p = 0.002), similar frequency of readmissions (87 vs 75%; p = NS), median survival greater in group IB (12.5 months vs 48 months) and significantly higher actuarial survival in group IB (48% in 2 years vs 83% to 2 years; p = 0.02) was observed. In conclusion, surgery is the treatment of choice in hiliary cholangiocarcinoma whenever possible, given the greater survival without a significant increase in morbimortality. Likewise, we consider that liver transplantation is a useful option in the treatment of patients with cholangiocarcinoma type IV of Bismuth.

Adult↗
PubMed1998

[Is surgery for portal hypertension a contraindication for liver transplantation?].

INTRODUCTION: Orthotopic liver transplantation (OLT) is the only curative treatment for hepatic cirrhosis and is the most effective in the control of portal hypertension. The aim of this study was to analyze whether greater morbi-mortality is observed in patients undergoing liver transplantation with previous surgery for portal hypertension with respect to patients not having undergone this surgery. MATERIALS AND METHODS: Different variables were analyzed in 2 groups of transplanted patients: one of 18 patients who had previously undergone surgery for portal hypertension and another group of 54 patients without this previous surgery. RESULTS: The following factors were studied: mean operative time and length of anahepatic phase, intraoperative consumption of concentrates of erythrocytes, fresh frozen plasma, units of platelets and cryoprecipitates, days of mechanical ventilation, stay in the ICU and total postoperative stay. No significant differences were observed (p < 0.05) in any of these factors or in survival. DISCUSSION: On analysis of the difficulty of surgical technique, postoperative evolution and survival and based on the variables described it may be concluded that previous surgery for portal hypertension does not only not contraindicate posterior liver transplantation, but rather may be useful in patients with an adequate hepative reserve presenting variceal hemorrhage since posterior transplantation does not present a worsened prognosis.

Adult↗
PubMed1997

Results of using the recipient's splenic artery for arterial reconstruction in liver transplantation in 23 patients.

BACKGROUND: Arterial reconstruction is essential in liver transplantation. In some patients there may be an inadequate flow as a result of stenosis, intimal dissection, or anomalies of the hepatic artery. METHODS: This study analyzes our experience with 23 patients in whom arterial anastomosis was performed using the splenic artery due to the inadequacy of the hepatic artery. During the same period an aortoiliac conduit was used in 12 liver transplantations due to the same problem. RESULTS: No splenic infarction, pancreatitis, or other related complications were found. Artery thrombosis developed in only two patients in the aortoiliac conduit group. One- and three-year patient actuarial survival were 78% vs. 80% and 72% vs. 80%, respectively, for the splenic artery group and the aortoiliac conduit group. CONCLUSIONS: Anastomosis with the splenic artery is an alternative in liver transplantation and is particularly suitable when splenomegaly is present.

Anastomosis, Surgical↗
PubMed1997

Vascular occlusion in hepatic resections in cirrhotic rat livers: an experimental study in rats.

The aim of this study was to evaluate the tolerance of normothermic liver ischemia with different degrees of hepatic function in cirrhotic rats. Liver cirrhosis was induced by administering carbon tetrachloride (CCl4) in water solution to male Wistar rats. Hepatic function was graded using the plasma levels of antithrombin III, albumin, and bilirubin and the presence of ascites. Rats were distributed in four groups: noncirrhotic (control group), compensated cirrhosis (group A), decompensated cirrhosis (group B), and decompensated cirrhosis with ascites (group C). Groups A, B, and C were significantly different in all four parameters studied (P < .003). Subtotal liver ischemia was performed for periods of 0, 30, 45, 60, and 75 minutes. At the end of the procedure, the nonischemic lobes were resected. Postoperative evolution of alanine aminotransferase, aspartate aminotransferase, and bilirubin levels was also recorded. Survival rates after the same periods of ischemia were statistically different (P < .05): control group, 7 of 7 after 45 minutes (100%), 7 of 7 after 60 minutes (100%), and 4 of 9 after 75 minutes (44%); group A, 7 of 7 after 45 minutes (100%) and 1 of 7 after 60 minutes (14%); group B, 7 of 7 after 0 minutes (100%), 5 of 7 after 30 minutes (71%), and 1 of 7 after 45 minutes (14%); and group C, 0 of 5 after 0 minutes (0%) and 1 of 7 after 30 minutes (14%). No differences were found in the postoperative course of transaminases. However, bilirubin levels found 24 hours and 7 days after ischemia were significantly greater in cirrhotic rats, and this was directly related to the degree of hepatic insufficiency (P < .001). Histological examination of the livers exposed to CCl4 showed features of liver cirrhosis with ductal proliferation. The ischemia time tolerated by cirrhotic rat livers is shorter than the time tolerated by normal rats. Tolerance to hilar vascular occlusion depends on the degree of hepatic insufficiency. Rats with decompensated cirrhosis and ascites do not tolerate any surgical procedure.

Alanine Transaminase↗
PubMed1997

Double-barreled wet colostomy: a safe and simple method after pelvic exenteration.

UNLABELLED: The clinical and functional outcome of ureteric division to the distal segment of a loop colostomy: the double-barrelled wet colostomy have been analysed. METHODS: 13 patients (8 female and 5 male, age 37 to 72 years) underwent pelvic exenteration with double-barrelled wet colostomy. The primary tumour included endometrial (n = 6), rectal (n = 1), anal (n = 1), cervical (n = 2), prostatic (n = 1) and bladder (n = 2). Indications for pelvic exenteration were locally advanced disease, recurrence and severe radiation or surgical damage. Six patients had pre-existing colostomy, and three had a Bricker ureteroileal diversion. The double-barrelled-wet colostomy technique consisted in anastomosing both ureters to a colon segment 25 cm distal to the loop colostomy. There was no operative mortality. Complications included one urinary leak which closed with conservative management and one case of recurrent episodes of pyelonephritis which finally required nephrectomy. Intravenous urography in the remaining patients showed good flow through the ureters to the conduit with no reflux. Postoperative plasma electrolytes, urea and creatinine were normal from day seven onwards. Urodynamic studies in four patients showed efficient contraction of the colon conduit with pressure levels similar to those in the colon proximal to the colostomy. In five cases biopsies of the conduit were taken at 3 and 16 months; no dysplasias were found. Four patients died due to disease progression. The overall mean survival was 41.2 months. The remainder are currently disease-free, maximum followup period being 19 months. Double-barrelled wet colostomy is a safe and simple technique with low morbidity. The patient needs to carry only one stoma and functional results are good.

Adult↗
PubMed1997

GTSF-2: a new, versatile cell culture medium for diverse normal and transformed mammalian cells.

The aim of this study was to test the versatility of a new basal cell culture medium, GTSF-2. In addition to traditional growth-factors, GTSF-2 contains a blend of three sugars (glucose, galactose, and fructose) at their physiological levels. For these studies, we isolated normal endothelial cells from human, bovine, and rat large blood vessels and microvessels. In addition, GTSF-2 was also tested as a replacement for high-glucose-containing medium for PC12 pheochromocytoma cells and for other, transformed cell lines. The cell growth characteristics were assessed with a novel cell viability and proliferation assay, which is based on the bioreduction of the fluorescent dye, Alamar Blue. After appropriate calibration, the Alamar Blue assay was found to be equivalent to established cell proliferation assays. Alamar Blue offers the advantage that cell proliferation can be measured in the same wells over an extended period of time. For some of the cell types (e.g., endothelial cells isolated from the bovine aorta, the rat adrenal medulla, or the transformed cells), proliferation in unmodified GTSF-2 was equivalent to that in the original culture media. For others cell types (e.g., human umbilical vein endothelial cells and PC12 cells), GTSF-2 proved to be a superior growth medium, when supplemented with simple additives, such as endothelial cell growth supplement (bFGF) or horse serum. Our results suggest that GTSF-2 is a versatile basal medium that will be useful for studying organ-specific differentiation in heterotypic coculture studies.

Animals↗
PubMed1997

Quantification of upper extremity function using kinematic analysis.

OBJECTIVE: To illustrate the applicability of motor control analytical techniques to the assessment of upper limb dysfunction in children with ataxia. DESIGN: Descriptive case series. SETTING: The study sample was selected from an outpatient pediatric rehabilitation clinic and testing was performed in a research laboratory. PARTICIPANTS: Four children with upper limb ataxia and seven healthy children were examined. All subjects were recruited on a volunteer basis. Criteria for inclusion (ataxic group) included: (1) age 6 to 15 yrs; (2) ambulatory with assistive devices. MAIN OUTCOME MEASURES: Quantitative measures of elbow kinematics (movement speed and duration) and spatio-temporal "portraits" of elbow movement during unilateral and bilateral forward reaching movements. RESULTS: Movements made by ataxic subjects were characterized by lower peak velocities, prolonged durations, and increased variability compared with normal subjects. In the one subject with unilateral ataxia, interlimb coordination was severely disrupted during the performance of coupled, bilateral arm movements. In addition to changes in specific kinematic values (eg, peak velocity), phase plane and angle-angle displacement curves revealed marked spatio-temporal variability throughout the movement, the magnitude of which was correlated with severity of ataxia. CONCLUSION: The application of the quantitative motor control methods described in this report can provide rehabilitation specialists with a simple yet sensitive means to evaluate treatment and progression of a wide variety of motor disorder conditions. These techniques are particularly well suited to pediatric populations as young as 6 years.

Adolescent↗
PubMed1997

Group B streptococcus colonization in pregnant diabetic women.

OBJECTIVE: To evaluate the influence of maternal diabetes on the risk of group B streptococcus colonization during pregnancy. METHODS: We prospectively analyzed data on 105 pregnant women with diabetes mellitus, both pregestational and gestational, and a control group of 300 pregnant women without carbohydrate intolerance. All had singleton gestations, negative tests for human immunodeficiency virus, and intact membranes at enrollment. Culture specimens for group B streptococcus were obtained from the lower vaginal walls and rectum. Two-tailed unpaired Student t test, Mann-Whitney U test, and chi 2 test were used as appropriate. Multiple logistic regression analyses were performed to evaluate the independent influence of maternal diabetes on the rate of group B streptococcus colonization. RESULTS: Compared to controls, diabetic women had a higher colonization rate (43.8 versus 22.7%, odds ratio [OR] 2.56, 95% confidence interval [CI] 1.6, 4.1). The prevalence of group B streptococcus colonization in pregestational diabetic women was 54.1% and in women with gestational diabetes it was 35.1% (P = .05). Among women with pregestational diabetes, the prevalence of group B streptococcus colonization was 59.1% in class B and 50.0% in class C to R (P = not significant). After we adjusted for maternal age, race, and obesity, diabetic women continued to be at increased risk of group B streptococcus colonization (OR 3.1, 95% CI 1.8, 5.2). CONCLUSION: Carbohydrate intolerance appears to be an independent risk factor for group B streptococcus colonization during pregnancy.

Adult↗