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E Duarte

Publications and source records attributed to E Duarte.

At least 19 recordsLinked to original sources
PubMed2006

Evaluation of chemical and ecotoxicological characteristics of biodegradable organic residues for application to agricultural land.

The use of organic waste and compost as a source of organic matter and nutrients is a common practice to improve soil physico-chemical properties, meanwhile reducing the need for inorganic fertilisers. Official guidelines to assess sewage sludge and compost quality are mostly based on total metal content of these residues. Measurement of the total concentration of metals may be useful as a general index of contamination, but provides inadequate or little information about their bioavailability, mobility or toxicity when the organic residue is applied to the soil. However, ecotoxicity tests provide an integrated measure of bioavailability and detrimental effects of contaminants in the ecosystem. In the present study, three different types of biodegradable organic residues (BORs) have been considered: sewage sludge from municipal wastewater treatment (SS), compost from the organic fraction of unsorted municipal solid waste (MSWC), and garden waste compost (GWC). The BORs were subjected to chemical characterisation and total metal quantification (Cd, Cr, Cu, Ni, Pb and Zn), in order to verify their suitability for land application. Water leachability was determined through the DIN 38414-S4 method, while the modified BCR sequential extraction procedure was used for metal speciation. Ecotoxicity of the BORs was studied by direct and indirect bioassays. Direct toxicity bioassays were: plant growth tests with cress (Lepidium sativum L.) and barley (Hordeum vulgare L.), and earthworm (Eisenia fetida) mortality. On the other hand, indirect exposure bioassays, with leachate from the residues, took into account: luminescent bacteria (Vibrio fischeri), seed germination (L. sativum and H. vulgare) and Daphnia magna immobilization. As far as total metal concentration is concerned, with particular reference to Zn, SS resulted neither suitable for the use in agriculture nor compatible to be disposed of as an inert material into landfill, according to the Directive 1999/31/EC. Zinc in SS was mainly present in exchangeable form (28.5%), appearing as highly bioavailable. As a consequence, SS exhibited either high ecotoxicity effects with the indirect exposure bioassays or significant mortality with the earthworm bioassay. Total content of metals in MSWC allowed its classification as "stabilised biowaste", according to 2nd draft [DG Env.A.2. Working document of Biological treatment of biowaste - 2nd draft. Directorate-General Environment, Brussels, 12th February; 2001. accessed in:http://europa.eu.int/comm/environment/waste/facts_en.htm, at 10/09/2002] while leachate, on the basis of the concentration of these contaminants, could be classified as "inert waste". This residue showed significant ecotoxicity effects with direct exposure bioassays as well as with the luminescent bacteria bioassay. However, it resulted less toxic than SS. Finally, GWC could be classified as a Class 2 compost, with no detectable toxic effects on the organisms used in the bioassays, except for the luminescent bacteria. In this case, an EC(50) of 73.0% was observed. Considering the results, the use of a battery of toxicity test in conjunction with chemical analysis should be suggested, in order to correctly assess possible environmental risks deriving from disposal or land application of biodegradable organic residues.

Agriculture↗
PubMed2006

[Short form 36 health questionnaire in hemiplegic patients 2 years after stroke].

INTRODUCTION: Many studies show that subjects with sequelae after stroke have a worse health perception in western societies. Due to the shortage of papers on the Spanish population in this regard, a study was carried out to assess health perception in hemiplegic patients 2 years after stroke in comparison with that of the general population and correlate health perception with demographic, clinical and functional variables. METHODS: Cross-sectional study of 212 community stroke survivors. The main variables collected were: health perception assessed with the Short Form 36 (SF-36), disability assessed with the motor Functional Independence Measure (FIM) and Geriatric Depression Scale (GDS). Statistical tests used: chi2, Student t test and Spearman correlation coefficient. RESULTS: In comparison with the Spanish general population, health perception in hemiplegic male stroke patients is diminished in all areas. In hemiplegic female patients, physical function is the only subscale significantly affected in all age groups. Variables related to worse health perception are: presence of depression, dependence and the belief of the need for kind of social support, A significant correlation was observed between SF-36 values and the motor FIM (r = 0.737 with physical function) and the GDS (r = -0.821 with mental health). CONCLUSIONS: Health perception in hemiplegic patients 2 years after stroke is diminished in comparison with that 348 of the general population. Factors which determine worst health perception are depression, motor dependence, need of caregiver assistance and need of social support.

Activities of Daily Living↗
PubMed2002

Trunk control test as a functional predictor in stroke patients.

The purpose of this study was to evaluate prospectively the Trunk Control Test (TCT) correlation at admission to rehabilitation with length of stay, functional independence measure (FIM), gait velocity, walking distance and balance measured at discharge in 28 hemiparetic patients. FIM and TCT were registered on admission. Outcome measures at discharge were: FIM, gait velocity, walking distance and balance assessed with the Berg Balance Scale and computerized posturography. TCT was significantly correlated with length of stay (r = -0.722), discharge FIM (r = 0.738), discharge motor FIM (r = 0.723), gait velocity (r = 0.654), walking distance (p = 0.003), centre of gravity symmetry r = 0.601) and Berg Balance Scale (r = 0.755). Initial TCT predicts the 52% of the variation in length of stay and 54% in the discharge FIM. The predictive value of a compound variable (TCT and admission FIM) reaches 60% of the variation in length of stay and 66% in the FIM at discharge.

Activities of Daily Living↗
PubMed2001

Diabetes in Bolivia.

OBJECTIVE: To measure the prevalence of diabetes mellitus (DM), hypertension, obesity, and related risk factors in major cities in Bolivia. METHODS: A population-based survey was conducted in four Bolivian cities: La Paz, El Alto, Santa Cruz, and Cochabamba. The total sample size was chosen to be 2,948 persons. The overall response rate was 86%, with the rate varying somewhat among the four cities. DM was diagnosed through an oral glucose tolerance test (OGTT) 2 hours after an overload of 75 grams of glucose, using World Health Organization criteria. RESULTS: The overall prevalence of DM in the four urban areas combined was 7.2% (95% confidence interval (CI): 6.2%-8.3%) and of impaired glucose tolerance (IGT) was 7.8%. A total of 73.1% (95% CI: 65.0%-81.0%) of those previously diagnosed with DM and 73.7% (95% CI: 61.0%-86.4%) of newly diagnosed cases were overweight, according to measurements of body mass index. Hypertension was found in 36.5% (95% CI: 27.6%-45.5%) of known diabetics and in 36.6% (95% CI: 23.0%-50.1%) of newly diagnosed cases, compared to only 15.9% (95% CI: 14.3%-17.5%) among people without DM. The disease was most common among older persons and those with little education. CONCLUSIONS: Diabetes is a genuine public health problem in Bolivia. Further, the high prevalence of IGT that was found suggests that diabetes prevalence will increase in the near future in the country unless prevention strategies are implemented.

Adult↗
PubMed2000

Inhibition of CCR5-dependent HIV-1 infection by hairpin ribozyme gene therapy against CC-chemokine receptor 5.

CCR-5 is a major cellular coreceptor for R5 strains of HIV-1. Individuals carrying a homozygous 32-base-pair deletion in this gene are apparently healthy and are relatively resistant to HIV-1 infection. Since CCR5 appears to be dispensable for the host, but important for initial HIV-1 infection, CCR5 mRNA is an excellent therapeutic target for inhibiting HIV-1 replication via ribozyme knockout. We report here that hairpin ribozymes are able to reduce cellular CCR5 mRNA and cell surface CCR5 when stably introduced into PM1 cells by transduction with recombinant adenoassociated viral vector. The ribozymes effectively protect the cells from infection by R5 HIV-1 strains or non-syncytium-inducing clinical isolates commensurate with a reduction in CCR5 mRNA. These results suggest a novel gene therapy approach to preventing or slowing the disease progression of HIV-1 infection.

CCR5 Receptor Antagonists↗
PubMed1995

[Spontaneous remission of cervical epidural hematoma with pathological confirmation].

Spontaneous cervical epidural hematoma (CEH) is a rare entity but one that can cause permanent neurologic deficit unless, it is widely believed, surgical evacuation is prompt. A diagnosis of CEH is confirmed by computed tomography and/or magnetic resonance imaging. Spontaneous remission is unusual, with only 7 such cases reported in the literature as of 1993. We present a case of CEH with clinical remission and confirmation by neuroimaging in a patient who died of an unrelated cause. We conclude that when neurologic deficit is incomplete and there are no signs of clinical progression after 48 h, surgical treatment should not be applied routinely.

Aged↗
PubMed1992

Rapid fitness losses in mammalian RNA virus clones due to Muller's ratchet.

Muller's ratchet is an important concept in population genetics. It predicts that when mutation rates are high and a significant proportion of mutations are deleterious, a kind of irreversible ratchet mechanism will gradually decrease the mean fitness of small populations of asexual organisms. In contrast, sexual recombination may stop or reverse this mutational ratchet by recombinational repair of genetic damage. Experimental support for Muller's ratchet has previously been obtained in protozoa and in a tripartite RNA bacteriophage. We now show clear evidence that Muller's ratchet can operate on a nonsegmented nonrecombining pathogenic RNA virus of animals and humans. We did genetic bottleneck passages (plaque-to-plaque transfers) of vesicular somatitis virus (VSV) and then quantitated relative fitness of the bottleneck clones by allowing direct replication competition in mixed infections in cell culture. We document variable fitness drops (some severe) following only 20 plaque-to-plaque transfers of VSV. In some clones no fitness changes (or only insignificant changes) were observed. Surprisingly, the most regular and severe fitness losses occurred during virus passages on a new host cell type. These results again demonstrate the extreme genetic and biological variability of RNA virus populations. Muller's ratchet could have significant implications for variability of disease severity during virus outbreaks, since genetic bottlenecks must often occur during respiratory droplet transmissions and during spread of low-yield RNA viruses from one body site to another (as with human immunodeficiency virus). Likewise, the lower-probability generation of increased-fitness clones during repeated genetic bottleneck transfers of RNA viruses in nature might also affect disease pathogenesis in infected individuals and in host populations. Whenever genetic bottlenecks of RNA viruses occur, enhanced biological differences among viral subpopulations may result.

Animals↗
PubMed1991

Quantitation of relative fitness and great adaptability of clonal populations of RNA viruses.

We describe a sensitive, internally controlled method for comparing the genetic adaptability and relative fitness of virus populations in constant or changing host environments. Certain monoclonal antibody-resistant mutants of vesicular stomatitis virus can compete equally during serial passages in mixtures with the parental wild-type clone from which they were derived. These genetically marked "surrogate wild-type" neutral mutants, when mixed with wild-type virus, allow reliable measurement of changes in virus fitness and of virus adaptation to different host environments. Quantitative fitness vector plots demonstrate graphically that even clones of an RNA virus are composed of complex variant populations (quasispecies). Variants of greater fitness (competitive replication ability) were selected within very few passages of virus clones in new host cells or animals. Even clones which were well adapted to BHK21 cells gained further fitness during repeated passages in BHK21 cells.

Animals↗
PubMed1989

Virus mutation frequencies can be greatly underestimated by monoclonal antibody neutralization of virions.

Monoclonal antibody-resistant mutants have been widely used to estimate virus mutation frequencies. We demonstrate that standard virion neutralization inevitably underestimates monoclonal antibody-resistant mutant genome frequencies of vesicular stomatitis virus, due to phenotypic masking-mixing when wild-type (wt) virions are present in thousandsfold greater numbers. We show that incorporation of antibody into the plaque overlay medium (after virus penetration at 37 degrees C) can provide accurate estimates of genome frequencies of neutral monoclonal antibody-resistant mutant viruses in wt clones. By using this method, we have observed two adjacent G----A base transition frequencies in the I3 epitope to be of the order of 10(-4) in a wt glycine codon. This appears to be slightly lower than the frequencies observed at other sites for total (viable and nonviable) virus genomes when using a direct sequence approach.

Animals↗
PubMed1986

Non-metric traits of the infracranial skeleton.

The authors have studied the right and left incidence of 30 non-metric infracranial variations in 2,103 dry bones of Brazilians and have concluded that the bilateral asymmetry is not significant in all but 2 traits: "The lateral tibial squatting facet" (X2 = 7.93) and "The peroneal tubercle present" (X2 = 20.35).

Anthropometry↗
PubMed1984

Marginal malnutrition and reduced physical work capacity of migrant adolescent boys in Southern Brazil.

We measured the effect of marginal malnutrition on physical work capacity of adolescent children of agricultural migrant workers in Southern Brazil. Nutritional status was evaluated using 24-h dietary recall. Body size was evaluated anthropometrically. Biochemical assessments were also made. Physical work capacity (PWC170) was assessed by measuring heart rate, blood lactic acid levels, and oxygen consumption during submaximal bicycle ergometer work. The same tests were also carried out on a comparable group of local well-to-do boys of the same age in the same community who served as controls. The dietary results suggest that adolescent boys of migrant families were marginally malnourished. Their physical growth and development were retarded by at least 1 yr. They had significantly lower reserves of body fat and less muscle mass when compared with controls. Their Hb levels were normal. At the submaximal work loads measured (0, 25, 50, 75 W) the migrant children exhibited similar oxygen consumption and gross exercise efficiency as the control children, but achieved this work at a higher percentage of their maximum work capacity as shown by significantly higher heart rates for the same oxygen consumption. Higher blood lactic acid levels in the migrant children suggest that the available muscle mass was under greater stress to accomplish the same task. PWC170 was reduced one-third in the migrant children (migrant 643 +/- 162 kpm/min, control 905 +/- 345 kpm/min; p less than 0.005). These differences were largely associated with weight (migrant 20.6 +/- 5.9 kpm/min; control 18.8 +/- 4.3 kpm/kg/min; p greater than 0.1). These observations suggest that marginal as well as severe malnutrition affect physical work capacity at levels low enough to affect growth and development.

Anthropometry↗
PubMed1982

Rotavirus viral RNA electrophoresis in hospitalized infants with diarrhea in Santiago, Chile.

Viral RNA electrophoresis technique was used to detect rotavirus in 226 children under 2 years of age with acute diarrhea, admitted to the Roberto del Río Hospital in Santiago, Chile, during the period of June 1979 through May 1980. A group of 50 children included in the aforementioned sample, admitted in winter, was compared with a control group of 25 infants without digestive pathology. In these groups, rotavirus was detected in 20 out of 50 children with diarrhea (40%) but not in the controls (0%). A positive diagnosis of rotavirus was found in 66 out of the total of 226 patients (29.2%); its monthly distribution ranged between a maximum of 83.3% (June) and a minimum of 11.1% (October).

Chile↗
PubMed1978

[Lactose intolerance in adults (author's transl)].

A study on the lactose intolerance of adults was carried out through dietary survey, clinical data and tolerance tests. It was performed in 24 healthy persons, aged 19 to 39 years. Only one of the participants referred milk intolerance since childhood. Eleven of the 24 adults had signs of lactose intolerance through clinical symptoms and/or low increase of blood sugar after the load test. It was noteworthy that the majority of the intolerants were white people. It is discussed the practical importance of these lactose tolerance tests as an index of milk tolerance, considering the high recommended amount of lactose used in the tests.

Adult↗