Universidade Federal de Rondônia

About: Universidade Federal de Rondônia is a education organization based out in Porto Velho, Brazil. It is known for research contribution in the topics: Population & Snake venom. The organization has 2232 authors who have published 2614 publications receiving 18062 citations.

Role of methylmercury exposure (from fish consumption) on growth and neurodevelopment of children under 5 years of age living in a transitioning (tin-mining) area of the western Amazon, Brazil.

Abstract: Human occupation of the Amazon region has recently increased, bringing deforestation for agriculture and open-cast mining, activities that cause environmental degradation and pollution. Families of new settlers in mining areas might have a diet less dependent on abundant fish and their children might also be impacted by exposures to mining environments. Therefore, there is compounded interest in assessing young children’s nutritional status and neurobehavioral development with regard to family fish consumption. Anthropometric (z-scores, WHO standards) and neurologic [Gesell developmental scores (GDS)] development in 688 preschool children (1–59 months of age) was studied. Overall, the prevalence of malnutrition [i.e., moderate stunting (≤2 H/A-Z), underweight (≤2 W/A-Z), and wasting (≤2 W/H-Z) were respectively 0.3% (n = 2), 1.6% (n = 11), and 2.5% (n = 17). Children’s mean hair Hg (HHg) concentration was 2.56 μg/g (SD = 1.67); only 14% of children had HHg concentrations lower than 1 μg/g and 1.7% had ≥5 μg/g. The biomarker of fish consumption was weakly but positively correlated with GDS (Spearman r = 0.080; p = 0.035). In the bivariate model, attained W/H-Z scores were not significantly correlated with GDS. A moderate level of GDS deficits (70–84%) was seen in 20% of children. There was significant correlation between family fish consumption and children’s hair Hg (HHg) (Spearman r = 0.1756; p < 0.0001) but no significant correlation between children’s HHg and W/H-Z scores. However, the multivariate model showed that breastfeeding, a fish consumption biomarker (HHg), maternal education, and child’s age were statistically significant associated with specific domains (language and personal-social) of the Gesell scale. In this mining environment, family fish-eating did not affect children’s linear growth, but it showed a positive influence (along with maternal variables) on neurodevelopment. Health hazards attendant on a high prevalence of moderate neurodevelopment delays coexisting with exposure to multiple neurotoxic substances merits further investigation in poor environmental settings of tin-mining areas.

Conteúdo cianogênico em progênies de mandioca originadas do cruzamento de variedades mansas e bravas

Abstract: As variedades de mandioca (Manihot esculenta Crantz ssp esculenta) sao classificadas pela taxonomia popular em bravas e mansas. As bravas tem sabor amargo, contem alto teor de glicosideos cianogenicos (superior a 100 mg de equivalente HCN/kg de polpa fresca de raiz) e sao consumidas apos serem processadas na forma de farinha, fecula e outros produtos. As mansas ou doces nao tem sabor amargo, contem baixo teor de glicosideos cianogenicos, sao consumidas com ou sem qualquer processamento, principalmente por meio de preparados domesticos simples. Neste trabalho, foram feitos cruzamentos para verificar o perfil cianogenico das progenies segregantes visando utilizar variedades bravas no melhoramento de mandiocas mansas. Duas variedades mansas (IAC 289-70 e IAC 576-70) e uma brava (SRT-1330 Xingu) foram polinizadas com uma variedade mansa (SRT-797 Ouro do Vale). Dos cruzamentos entre variedades mansas, 85,7% dos genotipos apresentaram teores abaixo de 100 mg eq. HCN/kg de polpa fresca de raiz. Do cruzamento entre as variedades mansa e a brava, apenas 31,3% dos genotipos mostraram teores abaixo desse valor. A media das progenies foi muito proxima a media dos parentais. Em todos os cruzamentos, a maior frequencia de genotipos esteve na classe entre 50 e 100 mg eq. HCN/kg de polpa fresca de raiz, mesmo no cruzamento entre brava e mansa. Em todos os cruzamentos apareceram segregantes transgressivos para maior e menor potencial cianogenico em relacao a qualquer parental. O tipo de segregacao observada indica ser a cianogenese um carater com heranca quantitativa que, embora tenha algum grau de influencia ambiental, torna possivel a selecao de individuos com maior ou menor teor cianogenico devido a alta herdabilidade oriunda de ampla variabilidade genotipica. Assim, variedades bravas podem surgir como recombinantes de variedades mansas, sendo tambem possivel selecionar variedades com baixo teor cianogenico em cruzamentos de mandiocas mansas com mandiocas bravas.

Nontuberculous mycobacteria in respiratory samples from patients with pulmonary tuberculosis in the state of Rondonia, Brazil

Abstract: The main cause of pulmonary tuberculosis (TB) is infection with Mycobacterium tuberculosis (MTB). We aimed to evaluate the contribution of nontuberculous mycobacteria (NTM) to pulmonary disease in patients from the state of Rondonia using respiratory samples and epidemiological data from TB cases. Mycobacterium isolates were identified using a combination of conventional tests, polymerase chain reaction-based restriction enzyme analysis of hsp65 gene and hsp65 gene sequencing. Among the 1,812 cases suspected of having pulmonary TB, 444 yielded bacterial cultures, including 369 cases positive for MTB and 75 cases positive for NTM. Within the latter group, 14 species were identified as Mycobacterium abscessus, Mycobacterium avium, Mycobacterium fortuitum, Mycobacterium intracellulare, Mycobacterium gilvum, Mycobacterium gordonae, Mycobacterium asiaticum, Mycobacterium tusciae, Mycobacterium porcinum, Mycobacterium novocastrense, Mycobacterium simiae, Mycobacterium szulgai, Mycobacterium phlei and Mycobacterium holsaticum and 13 isolates could not be identified at the species level. The majority of NTM cases were observed in Porto Velho and the relative frequency of NTM compared with MTB was highest in Ji-Parana. In approximately half of the TB subjects with NTM, a second sample containing NTM was obtained, confirming this as the disease-causing agent. The most frequently observed NTM species were M. abscessus and M. avium and because the former species is resistant to many antibiotics and displays unsatisfactory cure rates, the implementation of rapid identification of mycobacterium species is of considerable importance.

Temporal fish community responses to two cascade run-of-river dams in the Madeira River, Amazon basin

Abstract: We examined responses from shore fish assemblages and bottom channel fish assemblages before and after two cascade run-of-river dams in the Madeira River, in the Amazon. Those dams were installed in a river corridor where historical factors, represented by the presence of the Teotonio and Jirau falls, were the best predictors of the fish fauna assemblage composition. Jirau and Santo Antonio were the first dams constructed with Kaplan horizontal bulb turbines in the Amazon. These bulb turbines have the ability to operate by forming small reservoirs known as run-of-river, which should minimize impacts on fish assemblages. Overall, there were major short-term impacts in shore fish assemblages by increasing species richness, abundance and biomass in experimental catches. Shore fish assemblages dissimilarities before and after the dams’ closure were also noticed and were related to an increase in water temperature and dissolved oxygen. However, the historical factor represented by Teotonio Fall is still the best predictor of fish assemblage dissimilarities, combined with effects of dams’ closure. Bottom channel fish assemblage dissimilarities can be explained only by dams closure and are related especially to changes in fish species abundance inside the reservoirs. Our study revealed an increase in native opportunistic fish species and changes in fish assemblage structure at local scale. Kaplan horizontal bulb turbines employed in run-of-river dams seem to be less deleterious than vertical axis turbines typically used in accumulation reservoirs, and should be preferred in the face of burgeoning new hydroelectricity development plans for rivers across the Amazon basin.