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Biomedical subjects

R Valle

Publications and source records attributed to R Valle.

At least 19 recordsLinked to original sources
PubMed2006

Evaluation of investments in recycling centres for construction and demolition wastes in Brazilian municipalities.

There are very few construction and demolition (C&D) waste recycling centres in Brazil. To encourage the building and operation of new units, data were collected and analysed relating to C&D waste management and recycling in Brazil. Based on the results of this analysis, a conceptual model is presented for conducting viability studies of future C&D waste recycling centres. Applying this model to verify the viability of private recycling centres, the results show that under current market conditions in Brazil, C&D waste recycling centres are not financially feasible based solely on revenue from the sale of processed products. Nevertheless, under the same market conditions, the recycling centres could be economically viable for public authorities depending on the particular circumstances of each municipality. The feasibility, however, depends on continuity and the production volume reached. The conceptual model, the results of its applications and the discussions about the experiences of existing centres can strongly support public authorities and private initiatives in their decision-making about investments in Brazil and in other developing countries.

Brazil↗
PubMed2006

Acute venous thromboembolism in patients with recent major bleeding. The influence of the site of bleeding and the time elapsed on outcome.

BACKGROUND: Patients with major bleeding who subsequently develop clinically apparent venous thromboembolism (VTE) present a particularly difficult therapeutic dilemma. METHODS: RIETE is a prospective registry of consecutive patients with symptomatic, objectively confirmed, acute VTE. We retrospectively studied those who had experienced recent major bleeding (<30 days prior to VTE) to assess the influence of the site of bleeding and the time elapsed to VTE on their 3 month outcome. RESULTS: Of 12,294 patients enrolled up to July 2005, 306 (2.5%) had recent major bleeding: gastrointestinal (GI) tract, 116 (38%); intracranial, 94 (31%); other, 96 (31%). During the study period, 19 patients [6.2%; 95% confidence interval (CI) 3.5-8.9] with recent bleeding rebled (eight died): 13 of them (68%) during the first 2 weeks. Multivariate analysis confirmed that patients with recent GI bleeding had an increased risk for both major rebleeding (hazard ratio 2.8; 95% CI 1.4-5.3) and death (hazard ratio 1.9; 95% CI 1.2-3.1) compared to those with no recent bleeding. Those who bled in other sites had an increased risk only for death (hazard ratio 2.0; 95% CI 1.2-3.3). An elapsed time of <2 weeks from bleeding to the index VTE event was also associated with an increased risk for major rebleeding (hazard ratio 2.4; 95% CI 1.2-5.0) and death (hazard ratio 2.8; 95% CI 1.8-4.5). CONCLUSION: The incidence of new bleeding or death depends on the site of prior bleeding and the time elapsed until VTE. This information may help to identify the best therapeutic approach for these high-risk patients.

Acute Disease↗
PubMed2006

The BNP assay does not identify mild left ventricular diastolic dysfunction in asymptomatic diabetic patients.

AIMS: We examined the usefulness of BNP for screening for left ventricular (LV) diastolic dysfunction in a sample of type 2 diabetic patients, without structural heart disorder, who have never presented symptoms or signs of heart failure (HF). METHODS AND RESULTS: Seventy-six consecutive patients admitted to the Outpatient Diabetes Clinic were studied. Blood samples were analyzed using the Triage BNP fluorescence immunoassay (Biosite Diagnostics, La Jolla, CA, USA). Echocardiography examinations were performed, with no knowledge of the BNP value. A total of 39 patients out of 76 (51%) were diagnosed with LV diastolic dysfunction and 23 (30%) with LV hypertrophy. Of the patients with LV diastolic dysfunction, impaired relaxation and pseudonormal pattern accounted for 97 and 3% of the cases, respectively. BNP levels among subjects with LV diastolic dysfunction (26+/-22 pg/ml, n=39) were not significantly different from patients with normal LV function (24+/-23 pg/ml, n=37 pg/ml; Mann-Whitney U-test, Z=-0.4, n.s.). CONCLUSIONS: Our data confirm alarmingly high prevalence of LV diastolic dysfunction in asymptomatic individuals with diabetes. Identification of patients with preclinical diabetic cardiomyopathy should be a research and clinical priority. BNP levels cannot be used to detect mild LV diastolic dysfunction in this subset of patients, which requires Doppler echocardiography to be detected.

Aged↗
PubMed2004

Ethnic differences in social network help-seeking strategies among Latino and Euro-Aamerican dementia caregivers.

This research explores the help-seeking behavior of Euro-American and Latino caregivers who provide homecare assistance to an older adult with dementia. A community sample of 89 caregiver-care recipient pairs (39 Latino and 50 Euro-American) was interviewed. Descriptive, bivariate, and multivariate analyses were conducted to examine ethnic differences in use of an informal social network for help with caregiving tasks. Caregiver experiences that may impact help-seeking behaviors such as perceived availability of support network, satisfaction with support received and caregiver distress were also considered. Latino caregivers reported less help-seeking than did the Euro-American caregivers. Overall, ethnicity accounted for 16% of the variation in help-seeking behaviors. Ethnicity accounted for a significant portion of the variation in most of the help-seeking characteristics examined even after adjusting for socioeconomic variables. In the multivariate model, the effects of ethnicity on help-seeking persisted, while the effects of other likely predictors did not. The size of social network may not be synonymous with the seeking of support by caregivers. Likewise, higher levels of distress among Latino caregivers did not result in increased help-seeking behaviors. There remains a need to identity what other factors may contribute to the cultural variability in caregivers' use of informal support.

Aged↗
PubMed2004

The outcome after treatment of venous thromboembolism is different in surgical and acutely ill medical patients. Findings from the RIETE registry.

BACKGROUND: The history of venous thromboembolism (VTE), and the rationale for thromboprophylaxis in surgical patients are well understood. The situation is less clear for acutely ill medical patients. OBJECTIVES: To compare the clinical presentation of VTE and clinical outcomes of immobile acutely ill medical patients with surgical patients. PATIENTS: RIETE (Registro Informatizado de la Enfermedad TromboEmbolica) is a Spanish registry of consecutively enrolled patients with objectively confirmed, symptomatic acute VTE. In this analysis, clinical characteristics of patients, details of anticoagulant therapy, and outcomes of all enrolled acutely ill medical patients with immobility >/= 4 days, and surgical patients are included. RESULTS: Of 6160 patients enrolled up to December 2003, 756 (12%) were acutely ill medical patients with immobility >/= 4 days, and 884 (14%) were surgical patients who developed VTE within 2 months of surgical intervention. Only 28% of acutely ill medical patients had received thromboprophylaxis, compared with 67% of surgical patients. During the 3-month follow-up period, both fatal pulmonary embolism (PE) and fatal bleeding occurred more frequently in acutely ill medical patients. Immobility in acutely ill medical patients, cancer, and PE were associated with a significantly higher risk of fatal PE or bleeding. CONCLUSIONS: In patients treated for VTE, the incidences of fatal PE, fatal bleeding, and major bleeding were significantly higher in acutely ill medical patients compared with surgical patients. Given the low percentage of acutely ill medical patients who had received thromboprophylaxis, increasing its use appropriately may reduce the incidence of VTE and associated complications.

Acute Disease↗
PubMed2001

Poststreptococcal reactive arthritis in adults: long-term follow-up.

BACKGROUND: Poststreptococcal reactive arthritis (PSReA) is a recognized inflammatory articular syndrome that follows group A streptococcal infection in persons not fulfilling the Jones criteria for the diagnosis of acute rheumatic fever. Characteristic features include nonmigratory arthritis, lack of response to aspirin or nonsteroidal anti-inflammatory agents, and the presence of extra-articular manifestations, including vasculitis and glomerulonephritis. Whether or not patients with PSReA develop carditis is a point of contention. METHODS: We analyzed the clinical features, laboratory findings, response to therapy, and outcome in patients diagnosed with PSReA between 1983 and 1998 and observed through April 2000. All patients were contacted, reexamined, and repeat antistreptolysin, rheumatoid factor, C3 and C4 complement components, and echocardiograms were performed. RESULTS: Seventeen patients (4 men and 13 women) were included. All were of low socioeconomic status. All patients had acute severe arthritis that began shortly after a sore throat episode. Extra-articular involvement including tenosynovitis, vasculitis, and glomerulonephritis was relatively common. More importantly, none exhibited clinical and/or echocardiographic evidence of cardiac involvement. Longterm antibiotic therapy was not given. CONCLUSION: Cardiac involvement did not occur in this group of patients with PSReA. Prolonged prophylactic antibiotic therapy may not be required for adult patients presenting with PSReA.

Adolescent↗
PubMed2001

[Heart failure in nursing homes: prevalence, hospitalization, compliance to guidelines].

BACKGROUND: The prevalence of heart failure, the hospitalization rates for DRG 127 and the adherence to the recommendations included in the guidelines on pharmacological treatment among very old persons are poorly known. METHODS: We screened 141 very old subjects (75% females, aged 87+/-4 years), living in 2 nursing homes. Heart failure was defined according to clinical criteria and on the basis of administrative databases and chart reviews. The latter were also used to collect data on hospitalization rates and pharmacological therapy. RESULTS: We found that: 1) 23% of the subjects were affected by heart failure; 2) with regard to such patients, 26 hospital admissions for DRG 127 occurred in 1999 (18 admissions and 8 readmissions; 3) ACE-inhibitors have been prescribed to 54% of patients with a diagnosis of heart failure. CONCLUSIONS: Heart failure affects a huge number of very old persons living in nursing homes. These patients have high hospitalization rates for DRG 127. The adherence to the recommendations included in the guidelines on the pharmacological therapy for very old persons is poor.

Aged↗
PubMed2001

Cultural assessment in bioethical advocacy--toward cultural competency in bioethical practice.

The continued diversification of the U.S. population poses increasing challenges for bioethical advocates (e.g., ethicists, physicians, nurses, social workers, psychologists, surrogates, researchers, and lawyers), especially those serving rapidly expanding and culturally varied populations. The issue from the bioethics perspective is that the members of ethnically diverse groups often bring different normative expectations and their own preferred decision-making formats to the bioethics table. For example, some advocates will encounter a "collectivity," or the family-as-a-whole rather than the individual, as a decision maker. In other instances, they may encounter cultural groups whose members (or some of whose members) will value the principle of beneficence more than personal autonomy. Moreover, such value-based challenges are likely to continue since forecasters predict that diversification will actually quicken in the United States throughout the next five decades. In the face of these changes in the bioethical climate, advocates must be prepared to strengthen their cultural assessment skills. Taking a multidimensional approach to the problem yields a four-point cultural assessment model to help advocates handle the great diversity of outlook and orientation among their culturally diverse clientele.

Beneficence↗
PubMed1999

Assessment of student performance in problem-based learning tutorial sessions.

OBJECTIVES: To assess student performance during tutorial sessions in problem-based learning (PBL). DESIGN: A 24-item rating scale was developed to assess student performance during tutorial sessions in problem-based learning (PBL) as conducted during the pre-clinical years of Medical School at the National Autonomous University of Mexico. Items were divided into three categories: Independent study, Group interaction and Reasoning skills. Fourteen tutors assessed 152 first and second-year students in 16 tutorial groups. An exploratory factor analysis with an Oblimin rotation was carried out to identify the underlying dimensions of the questionnaire. SETTING: Medical School at the National Autonomous University of Mexico. SUBJECTS: Medical students. RESULTS: Factor analysis yielded four factors (Independent study, Group interaction, Reasoning skills, and Active participation) which together accounted for 76.6% of the variance. Their Cronbach reliability coefficients were 0.95, 0.83, 0.94 and 0. 93, respectively, and 0.96 for the scale as a whole. CONCLUSIONS: It was concluded that the questionnaire provides a reliable identification of the fundamental components of the PBL method as observable in tutorial groups and could be a useful assessment instrument for tutors wishing to monitor students' progress in each of these components.

Adult↗
PubMed1998

Characterization of MLH1 and MSH2 alternative splicing and its relevance to molecular testing of colorectal cancer susceptibility.

The phenomenon of alternative splicing in the DNA mismatch repair genes MLH1 and MSH2 was extensively investigated by coupled reverse transcription-polymerase chain reaction in different human tissues, including 42 mononuclear blood cell samples--31 obtained from familial colon cancer patients or their at-risk relatives and 11 from healthy blood donors--7 normal colonic mucosae, 4 established human cancer cell lines, 8 colorectal tumors, and one sample each of ileum, liver, muscle, thymus, breast, and EBV-transformed lymphoblasts. Several isoforms were observed for each gene. Products of MLH1 alternative splicing included mRNAs lacking alternative exons 6/9, 9, 9/10, 9/10/11, 10/11, 12, 16, and 17. For MSH2, products lacking exons 5, 13, 2 through 7, and 2 through 8 were identified. The levels of expression were found to vary among different samples. All isoforms were found in a relevant fraction (43-100%) of the mononuclear blood cell samples, as well as in other tissues. The splicing variants were also detected in normal colonic mucosa, with the exceptions of the MLH1 -6/9 and -10/11 and the MSH2 -13 isoforms. Germline mutations of MLH1 and MSH2 confer constitutional predisposition to the development of colorectal cancer and other neoplasms. A substantial proportion of the mutations identified so far involve alterations of the normal splicing process. Knowledge of the existence of multiple alternative splicing events, not caused by genomic DNA changes, is important for the evaluation of the results of molecular diagnostic tests based on RNA analysis.

Adaptor Proteins, Signal Transducing↗
PubMed1997

Loss of heterozygosity at the 5,10-methylenetetrahydrofolate reductase locus in human ovarian carcinomas.

The high-affinity folate-binding protein (FBP) is primarily involved in the uptake of the 5-methyltetrahydrofolate, and its expression may be physiologically regulated by the intracellular folate content. The overexpression of FBP on the cell surface of ovarian carcinoma cells may be responsible for an increased folate uptake. We tested the hypothesis of the existence of a defect in the 5, 10-methylenetetrahydrofolate reductase (MTHFR) in ovarian tumours that could cause reduced intracellular regeneration of the 5-methyltetrahydrofolate and induce increased FBP expression. No sequence mutations were found in the MTHFR gene, but allelic deletions of this gene were frequently detected in ovarian tumours (59%). Chromosomal losses appeared to be confined to the 1p36.3 region to which the MTHFR gene maps. Although it cannot be stated that MTHFR is the target gene of the chromosomal loss involving the 1p36.3 region, a correlation between loss of heterozygosity at this locus and decrease in MTHFR activity was shown, suggesting a role of these allelic deletions in generating a biochemical defect in folate metabolism. Further studies are needed to assess further the relationship between MTHFR and FBP overexpression, but the demonstration of the alteration of a key metabolic enzyme of the folate cycle in a subset of human ovarian tumours is in accordance with the hypothesis of an altered folate metabolism in these neoplasias and might be exploited for therapeutic purposes.

5,10-Methylenetetrahydrofolate Reductase (FADH2)↗