Showing papers by "Universidade Federal de Mato Grosso published in 2001"

Contaminação do ambiente aquático por pesticidas. Estudo de caso: águas usadas para consumo humano em Primavera do Leste, Mato Grosso - análise preliminar

Abstract: A preliminary analyses of the possible contamination of superficial and underground water by the active ingredients of the pesticide products used in the surroundings of the urban area of Primavera do Leste, Mato Grosso, Brazil, was carried out. A description of the study region and of its environmental characteristics, which can favor the contamination of the local aquatic environment, was presented. The EPA screening criteria, the groundwater ubiquity score (GUS) and the criteria proposed by Goss were used to evaluate which pesticides might contaminate the local waters. Among the active ingredients studied, several present risks to the local aquatic environment.

Seasonal variations in the net ecosystem CO2 exchange of a mature Amazonian transitional tropical forest (cerradão)

Abstract: Summary 1. Tower-based eddy covariance and measurements of the vertical CO 2 concentration gradient within the canopy were used to quantify the seasonal variations in the net ecosystem CO 2 exchange (NEE) of a 28‐30 m tall transitional tropical forest (cerradao). The study was conducted near the city of Sinop, Mato Grosso, Brazil (11 ° 24·75 ′ S; 55 ° 19·50 ′ W), which is located in the ecotone of two major regional ecosystem types of South America (tropical rainforest and savanna). 2. The NEE during the dry season (August‐September) was in balance, but during the transition period between the dry and wet seasons (October‐November) the cerradao stand became a net source of 50‐150 mmol m ‐2 day ‐1 CO 2 to the atmosphere. Measurements during the wet season (February, April) indicate that the forest was a net sink of between ‐55 and ‐102 mmol m ‐2 day ‐1 . 3. The NEE of the transitional tropical forest was more similar to that of tropical rainforest during the wet season, but during the dry season the NEE of the transitional forest was more similar to that reported for tropical savanna. The data suggest that seasonal variations in rainfall have important implications for the seasonal pattern of NEE in cerradao.

Flooding-tolerant legume symbioses from the Brazilian Pantanal

Abstract: Summary • Nodulated legumes in some of the flooded and seasonally flooded areas of the Pantanal Mato-Grossense wetlands in Brazil are described here. • In the permanently flooded lakes (baias) of the Caracara national park Discolobium pulchellum, Mimosa pellita, Sesbania exasperata and Vigna lasiocarpa (syn. Phaseolus pilosus) were the most abundant, whereas close to Corumba, at the edges of the river Paraguai, Neptunia spp. were also common. Adaptations that allow these legumes to fix N2 in a flooded environment included a floating growth habit, aerenchyma and nodulated adventitious roots. • By contrast, Aeschynomene spp. (A. ciliata, A. denticulata, A. fluminensis, and A. sensitiva) were the dominant nodulated legumes in the seasonally flooded pastures of Nhumirim. • Stem-nodulation was commonly observed, particularly on seasonally flooded Aeschynomene and seasonal/permanently flooded Discolobium spp., but also, in a modified form, on floating stems of V. lasiocarpa. The structures of stem and/or root nodules on Aeschynomene spp., Discolobium leptophyllum and V. lasiocarpa are described in detail, and nodulation by D. leptophyllum and Neptunia pubescens is reported for the first time.

[The influence of smoking on fertility, pregnancy and lactation]

Abstract: OBJETIVOS: descrever a influencia do tabagismo nas diferentes fases do processo reprodutivo, fecundacao, gestacao e lactacao, destacando os mecanismos de acao dos principais componentes toxicos do cigarro nestas fases. Sugerir medidas profilaticas de controle ambiental e de como reduzir a exposicao da crianca a fumaca do tabaco. METODOS: revisao bibliografica nao sistematica sobre os temas abordados, utilizando-se da base de dados do MEDLINE. RESULTADOS: o tabagismo atua negativamente nas diferentes fases da reproducao, por acao direta de seus principais componentes toxicos, a nicotina e o monoxido de carbono. Reduz a taxa de fertilidade, compromete a duracao da gestacao e o peso do concepto. Tambem diminui a producao de leite da nutriz fumante e o tempo de lactacao, comprometendo o ganho de peso da prole, por mecanismos ainda nao bem compreendidos, nos quais a prolactina pode estar envolvida. CONCLUSOES: os efeitos do tabagismo comprometem a qualidade da funcao reprodutiva em diferentes fases, por atuar principalmente sobre o desenvolvimento do concepto, tanto na fase intra quanto na fase extra-uterino. Por ser um periodo de contato mais frequente da mulher fumante com o profissional de saude, a gestacao e a lactacao deveriam ser alvo especial de campanhas antitabagicas.

As diferenças de estado nutricional em pré-escolares de rede pública e a transição nutricional

Abstract: OBJETIVO: verificar a existencia de diferencas de perfis nutricionais em pre-escolares de rede publica que justifiquem intervencoes diferenciadas. METODOS: trata-se de estudo seccional, realizado em 1.200 pre-escolares da rede publica de Cosmopolis, SP. Foram calculados escores de desvio-padrao para os indices altura/idade, peso/idade e peso/altura em relacao aos da populacao do NCHS. Os indices foram analisados segundo sexo, idade, escola frequentada e localizacao da escola nos setores urbanos do municipio. RESULTADOS: observou-se que as distribuicoes dos indices foram semelhantes as da populacao de referencia. Os meninos apresentaram medias de escore z mais baixas que as meninas. Houve diferenca significativa entre as medias de escore z em relacao a escola frequentada. Verificou-se prevalencia maior de criancas com deficits moderados de altura e peso nas escolas fora do centro e maior prevalencia de obesidade nas escolas do centro. Entretanto, mesmo nas escolas fora do centro, a prevalencia de obesidade foi superior a de deficiencia nutricional. CONCLUSOES: conclui-se que tambem em municipio de pequeno porte e em segmento da populacao relativamente homogeneo, e possivel verificar a existencia de diferentes padroes nutricionais em subgrupos da populacao. As diferencas observadas nos perfis nutricionais, conforme a escola frequentada e a localizacao da escola, apontam a necessidade de atencao e intervencoes distintas.

Prevalência e fatores associados a marcadores do vírus da hepatite B em população rural do Brasil central

Abstract: Objetivo. Realizar um inquerito soro-epidemiologico sobre infeccao pelo virus da hepatite B em um municipio do medio-norte do Estado de Mato Grosso, que corresponde a regiao limitrofe entre o cerrado e a bacia amazonica. Metodos. A amostra incluiu familias escolhidas aleatoriamente na sede do municipio, assim como toda a populacao de uma comunidade rural, totalizando 754 individuos. A idade variou de 2 a 79 anos. Os participantes foram entrevistados e tiveram amostras de sangue colhidas para pesquisa de marcadores do virus da hepatite B por metodo imunoenzimatico. Resultados. A infeccao pelo virus da hepatite B foi constatada em 31% da amostra, sendo 3% positivos para o HBsAg. Os 149 (20%) com historia de vacinacao e anti-HB positivo isoladamente foram considerados respondedores a vacina. As variaveis associadas a exposicao ao virus da hepatite B por analise multivariada foram: ja ter iniciado atividade sexual, ter sido vacinado com pistola pressurizada contra febre amarela (entre aqueles com menos de 20 anos) e ser migrante oriundo do Sul do Brasil (individuos com mais de 20 anos). A cobertura vacinal foi baixa entre individuos com mais de 10 anos de idade. O maior numero de suscetiveis (74%) foi encontrado na faixa dos 11 aos 20 anos. Conclusoes. No Brasil, a vacinacao contra a hepatite B deve ser estendida quanto antes aos adolescentes nas regioes de baixa a moderada prevalencia. E provavel que os dados obtidos no presente estudo possam ser extrapolados para outras regioes da America Latina com padrao epidemiologico semelhante.

Prevalence of hepatitis B and C virus markers among malaria-exposed gold miners in Brazilian Amazon

Abstract: Hepatitis B and C virus markers were assessed during a survey on malaria in gold mine camps in southern Brazilian Amazon in order to identify risk factors associated to these viral diseases. The study comprised 520 subjects, most of them were gold miners. Missing subjects totaled 49 (8.6%). Among these 520, 82.9% had HBV markers and 7.1% were HBsAg positive. Previous hospitalization, surgery, sexually transmitted diseases and incarceration were quite common among surveyed people, but there is no association between total HBV markers and these factors. On other hand, HBsAg was independently associated to history of sexually transmitted diseases and history of surgery after adjustment. The most frequent HBsAg subtypes identified, adw2 (59%), predominates in populations of Northeast Brazil. The most surveyed people were immigrants coming from that area suggesting that immigrants carried HBV themselves to the study area. Immunoblot (RIBA) confirmed-anti-HCV were found in 2.1%. The only variable associated to anti-HCV in multivariate analysis was illicit intravenous drug. Lack of HCV infection in subjects with such a high HBV markers prevalence reinforces the opinion that HCV is transmitted by restricted routes when compared to HBV. Furthermore, gold miners in Amazon may be considered as a risk group for HBV infection, but not for HCV.

Fatores de risco, aspectos clínicos e laboratoriais da asma em crianças

Abstract: OBJETIVO: avaliar os aspectos clinicos, laboratoriais, e os fatores de risco associados a asma em criancas atendidas no Ambulatorio de Pediatria, do Hospital Universitario Julio Muller. Metodo: estudo de caso-controle, incluindo 59 criancas asmaticas (casos) e 104 nao-asmaticas (controles). Os seguintes fatores foram considerados para analise de risco: escolaridade dos pais, exposicao aos alergenos domiciliares, tabagismo passivo, aleitamento materno, renda e antecedentes familiares alergicos. Foram coletadas amostras de sangue para hemograma e dosagem de IgE total e especifica para alergenos. Realizou-se teste cutâneo de hipersensibilidade imediata pelo metodo de puntura para os seguintes alergenos: acaros, animais, fungos e baratas com controles positivo (histamina) e negativo (solucao fisiologica).Um modelo de regressao logistica foi usado para calcular odds ratio (OR) e intervalo de confianca (IC) 95% ajustado para outros fatores de risco e confundidores. RESULTADOS: dentre os fatores de risco estudados, sexo, baixa escolaridade, baixa renda, tempo de aleitamento materno e tabagismo passivo nao estiveram associados a ocorrencia de asma. A exposicao aos alergenos foi semelhante nos dois grupos, a nao ser pela maior frequencia de animais nos domicilios dos controles (c2=16,9; P < 0,05). Rinite paterna foi o unico antecedente familiar associado a asma (OR=3,33; IC 95%:1,03-11,17; P < 0,05). As criancas asmaticas apresentaram maior frequencia de positividade do teste cutâneo que os controles, principalmente para acaros: Dermatophagoides pteronyssinus (69,5%), Dermatophagoides farinae (59,3%) e Blomia tropicalis (59,3%); baratas: Periplaneta americana (59,3%) e gato: Felis domesticus (37,3%); com OR variando de 11,2-21,0; p < 0,05. Eosinofilia e niveis sericos de IgE total foram mais elevados no grupo de asmaticos (p < 0,05). A positividade do teste de IgE especifica para Dermatophagoides pteronyssinus e Blomia tropicalis foi maior nos casos em relacao aos controles (P < 0,05). A analise multivariada mostrou que sensibilizacao as baratas (OR=9,26, 95%IC:2,59-33,4), animais (OR=3,93, 95%IC:1,05-14,67) e acaros (OR=3,74, 95%IC:1,18-11,8) foram os mais importantes fatores de risco para asma. CONCLUSOES: a sensibilizacao aos alergenos domiciliares, principalmente acaros, barata e animais mostrou uma forte associacao com asma neste estudo.

Prevalence of asthma in schoolchildren

Abstract: OBJECTIVE: To assess the prevalence of asthma symptoms and of asthma in children due to the high frequency of pediatrics patients with symptoms suggestive of the disease and to the lack of data regarding prevalence of asthma in this population. METHODS: We carried out a cross-sectional study with 2,735 school-age children aged 6-7 years and 3,509 adolescents aged 13-14 years selected by random sampling. Data were collected between 1998 and 1999 using a translated version of the questionnaire of the International Study of Asthma and Allergies in Children, which has been previously tested and approved. Guardians were responsible for answering the questionnaire of younger children, whereas adolescents answered their own, in classroom. The data were computed and analyzed using EPI-info software. RESULTS: The response rates for questionnaires were 73.2% (6-7-years old) and 94% (13-14 years old). The prevalence of symptoms in children and adolescents were, respectively: wheezing ever 46.7% and 44.3% (P<0.05); wheezing in the last 12 months 22.7% and 21.2%; speech limited due to wheezing 4.7% and 4.0%; wheezing following exercise 6.3% and 18.2% (P<0.05); nighttime cough in the last 12 months 38.5% and 45.8% (P<0.05); asthma (bronchitis) ever 28.2% and 26.4% (P=0.11). CONCLUSIONS: The prevalence of asthma symptoms and of asthma of the two groups are among the highest results ever reported in Brazil; these results were compatible with those of high prevalence results reported worldwide using ISAAC questionnaires. The high prevalence of symptoms suggests a high prevalence of the disease, which makes asthma an important problem for public health in the region.

The sweet jelly of Combretum lanceolatum flowers (Combretaceae): a cornucopia resource for bird pollinators in the Pantanal, western Brazil

Abstract: The pollination biology of the neotropical scandent shrub Combretum lanceolatum was studied in the seasonally-flooded Pantanal region in western Brazil. This plant bears horizontally oriented inflorescences, whose yellowish green flowers begin to expand at dusk and are fully open at dawn. Instead of fluid nectar the flowers produce sweet gelatinous secretion in form of pellets. The glandular complex of the flower is composed of the inner wall of the receptacle and its tubular extension, being equivalent to the nectariferous disk of the nectar-producing species within the genus. The jelly is produced at night, contains mannan and is imbibed by free hexoses. It originates by swelling and disintegration of the inner wall, after contact with the nectar generated concomitantly in the mesophyll. Combretum lanceolatum is unique within the genus in its production of jelly pellets instead of liquid nectar. A new term, the jelly-flower, is proposed for flowers with this kind of reward. The pellet is not replaced once removed by a bird, and thus resembles a fruit in its availability to consumers, another unique feature that distinguishes this species within the genus. The jelly pellets offered by the many flowered branches attract a great diversity of bird visitors (28 species from eight families), which feed on this copious food resource and pollinate the flowers. The most effective pollinators probably are thrushes, tanagers, and orioles. Flocking parakeets and macaws sometimes feed on the petals, thus acting as flower plunderers. Combretum lanceolatum presents a high fruit set under natural conditions, which likely favours its spreading and becoming a weed species.

Risk factors, clinical and laboratory aspects of asthma in children

Abstract: Objective: to evaluate the clinical and laboratory aspects and the risk factors associated with asthma in children treated at the Pediatric Outpatient Clinic of Hospital Universitario Julio Muller. Methods: a case-control study including 59 asthmatic children (cases) and 104 nonasthmatic children (controls). The following factors were considered for risk analysis: parents’ level of education, domestic exposure to allergens, passive smoking, breast feeding, low income, and family history of allergy. Samples of blood were collected for hemogram and to determine the total serum IgE as well as the one specific to allergens. Immediate hypersensitivity skin tests were performed with puncture for the detection of the following allergens: house dust mite, animals, molds, and cockroaches with positive (histamine) and negative controls (physiologic solution). A logistic regression model was used to calculate the odds ratio (OR) and 95% confidence intervals (95%CI) adjusted for risk factors and for confounding factors. Results: among the risk factors studied, sex, parents’ low level of education, low income, length of the breast feeding period, and passive smoking were not associated with the presence of asthma. The domestic exposure to allergens was similar in both groups except for the higher frequency of pets at the homes of control patients (χ2=16.9; P<0.05). Paternal history of rhinitis was the only association with asthma (OR=3.33; 95%CI: 1.03-11.17; P<0.05). The asthmatic children presented higher frequency of positive reactions to skin tests than the controls, mainly to house dust mites: Dermatophagoides pteronyssinus (69.5%), Dermatophagoides farinae (59.3%) and Blomia tropicalis (59.3%); cockroaches: Periplaneta americana (59.3%), and cat: Felis domesticus (37.3%), with OR between 11.2-21.0; P<0.05. Eosinophilia and serum levels of total IgE were more elevated in the group of asthmatic children (P<0.05). The positivity of the specific IgE test for Dermatophagoides pteronyssinus and Blomia tropicalis was higher in the cases than in the controls (P<0.05). The multivariate analysis showed that sensitization to the allergens produced by cockroaches (OR=9.26; 95%CI: 2.59-33.4), animals (OR=3.93; 95%CI: 1.05-14.67) and house dust mites (OR=3.74; 95%CI: 1.18-11.8) were the most important risk factors for asthma. Conclusions: the sensitization to indoor allergens, mainly to house dust mites, cockroaches, and cats showed a strong association with asthma in this study.

Alexandre Rodrigues Ferreira e a capitania de Mato Grosso: imagens do interior

Abstract: At the crucial moment when frontier boundaries between the two Iberian Americas were being established, Alexandre Rodrigues Ferreira carried out his Philosophical Journey into Brazilian lands. From 1789 to 1791, his expedition crossed the capitania de Mato Grosso until the far lowlands of Pantanal. From the analysis of the texts and other records produced during the trip, some of the first images of Brazilian inland come to light.

FATOR DE FORMA ARTIFICIAL DE Pinus elliottii Engelm PARA A REGIÃO DA SERRA DO SUDESTE DO ESTADO DO RIO GRANDE DO SUL

Abstract: O presente trabalho foi desenvolvido com o proposito de estudar o fator de forma artificial de Pinus elliottii Engelm para a regiao da Serra do Sudeste do Estado do Rio Grande do Sul. Para tanto, estudou-se o desenvolvimento do fator de forma artificial em funcao de variaveis dendrometricas, alem da confeccao de tabelas de fator de forma para uso regional. Dentre os modelos estudados, o que melhor ajustou a variavel dependente foi o expresso por, sendo: d o diâmetro a altura do peito, d0,5 e d0,3 os diâmetros relativos de Hohenadl, tendo apresentado um coeficiente de determinacao igual a 0,89 e um coeficiente de variacao de 3,59%. Os diâmetros relativos de Hohenald da equacao de fator de forma foram estimados atraves das equacoes: ln(d0,5) = -0,27211 + 0,97542* ln(d) e ln(d0,3) = -0,62082 + 0,26949 * ln(d²) + 0,22483* ln(d*h), tendo apresentado coeficiente de determinacao de 0,91 e 0,99 e coeficiente de variacao 4,23 e 8,21%, respectivamente.

África do Sul e Brasil: diplomacia e comércio (1918-2000)

Abstract: O principal objetivo do artigo e analisar as relacoes entre o Brasil e a Africa do Sul em perspectiva historica. Uma vez iniciadas, essas relacoes atravessaram tres grandes fases. No primeiro momento, que foi de 1918 a 1947, prevaleceu o comercio como fator da aproximacao, constituindo-se tal periodo em momento de encontros e descobertas mutuas. A segunda fase, de 1947 a 1991, foi marcada pelo estabelecimento de relacoes diplomaticas e pelo gradual distanciamento entre os dois paises. A ultima grande fase vem sendo marcada pela reaproximacao entre Brasilia e Pretoria, uma vez que foi removido o principal empecilho para a concretizacao de relacoes prosperas entre os dois paises, ou seja, o fim da politica de apartheid. Durante esse ultimo periodo, iniciado com o processo de democratizacao da Africa do Sul no alvorecer da decada de 1990, ha o renascimento das relacoes, em um contexto em que se vislumbra a possibilidade do estabelecimento de uma parceria estrategica, que interessa diretamente aos dois paises.

Magnesium deficiency improves glucose homeostasis in the rat: studies in vivo and in isolated islets in vitro.

Abstract: The serum mineral levels, glucose disappearance rate (kg), total area under the glucose (DeltaG) and insulin (DeltaI) curves, and static insulin secretion were compared among rats fed a Mg-deficient diet for 6 (DF-6) or 11 (DF-11) weeks, and rats fed a control diet for the same periods (CO-6 and CO-11 groups). No change in glucose homeostasis was observed among DF-6, CO-6 and CO-11 rats. DF-11 rats showed an elevated kg and a reduced DeltaG and DeltaI. For evaluating the effect of supplementation, rats fed a control or Mg-deficient diet for 6 weeks were then fed a Mg- supplemented diet for 5 weeks (SCO and SDF groups respectively). The serum Mg levels in SDF rats were similar to those in CO-11 and SCO rats, but higher than in the DF-11 group. SDF rats showed similar kg, DeltaG and DeltaI compared with the CO-11 and SCO groups. However, a significantly lower kg and higher DeltaG and DeltaI were observed in SDF compared with DF-11 rats. Basal and 8.3 mmol glucose/l-stimulated insulin secretion by islets from DF-11 rats were higher than by islets from CO-11 rats. These results indicate that moderate Mg depletion for a long period may increase the secretion and sensitivity to insulin, while Mg supplementation in formerly Mg-deficient rats may prevent the increase in sensitivity and secretion of insulin.

Differences between the nutritional status of children in public preschools and nutritional transition

Abstract: Objective: to verify if there are different patterns of nutritional status among preschool children, and if these patterns deserve special interventions. Methods: this cross-sectional study included 1,200 children from public preschools in Cosmopolis, a small town in the state of Sao Paulo. The z scores indices for height/age, weight/age, and weight/height were analyzed in terms of age, sex, type of school, and school location. Results: anthropometric indices were similar to those of the reference population (NCHS). Males had lower indices than females. Important differences in anthropometric indices were found among children from different schools. Higher prevalence of moderate deficits in height and weight was observed in children from non-downtown areas, while higher prevalence of obesity was found in children from downtown areas. However, the prevalence of obesity was higher than the prevalence of malnutrition even in schools located in non-downtown areas. Conclusions: we concluded that even in a small city and in a relatively homogeneous group, it is possible to detect different nutritional patterns in subgroups of the population. The differences related to nutritional status, and the high prevalence of obesity among children from public schools, point out the need for different approaches and interventions.

Avaliação de caracteres vegetativos de híbridos de coqueiro (cocos nucifera l.) na região não pantanosa do município de poconé, mt

Abstract: O presente estudo foi realizado entre marco de 1999 e marco de 2000, na regiao de Cangas, municipio de Pocone, MT, com a finalidade de estudar o desenvolvimento inicial de hibridos intervarietais de coqueiros, avaliados para as caracteristicas: circunferencia do coleto (CC), numero de folhas vivas (NFV), numero de folhas emitidas (NFE), numero de foliolos da folha 3 (NFoF3), comprimento de foliolos da folha3 (CFoF3), comprimento da folha 3 (CF3) e comprimento do peciolo da folha 3 (CPF3). Utilizou-se o delineamento experimental em blocos casualizados, com quatro repeticoes e cinco tratamentos, tendo em cada parcela 16 plantas uteis. Os resultados das analises estatisticas demonstraram haver diferenca significativa para todas as caracteristicas. O hibrido AVG x GBrPF foi o que melhor expressou o "vigor hibrido" com maiores CC, NFoF3, CFoF3 e CF3. Por outro lado, o AVeJ x GBrRN apresentou os menores valores para estas caracteristicas, embora tenha expressado o melhor resultado para NFE e NFV nas avaliacoes finais.

AGENTES INFECCIOSOS ISOLADOS DE Chinchilla laniger

Abstract: This report describes a case of infection for Pseudomonas aeruginosa and outbreaks caused by Bordetella bronchiseptica in chinchila farms from the region of Santa Maria, Southern Brazil. The affected animals presented apathy, anorexia, respiratory impairment and nasal secretion. The isolation of Pseudomonas aeruginosa was carried out through the culture of samples of lung whereas Bordetella bronchiseptica was obtainedfrom lung, liver and swab of traqueal secretion. In this report, the clinical data and the pathological findings as well as the isolation and identification of these agents are described.

Magnesium Deficiency Improves Glucose Homeostasis In The Rat: Studies In Vivo And In Isolated Islets In Vitro.

Abstract: The serum mineral levels, glucose disappearance rate (kg), total area under the glucose (DeltaG) and insulin (DeltaI) curves, and static insulin secretion were compared among rats fed a Mg-deficient diet for 6 (DF-6) or 11 (DF-11) weeks, and rats fed a control diet for the same periods (CO-6 and CO-11 groups). No change in glucose homeostasis was observed among DF-6, CO-6 and CO-11 rats. DF-11 rats showed an elevated kg and a reduced DeltaG and DeltaI. For evaluating the effect of supplementation, rats fed a control or Mg-deficient diet for 6 weeks were then fed a Mg- supplemented diet for 5 weeks (SCO and SDF groups respectively). The serum Mg levels in SDF rats were similar to those in CO-11 and SCO rats, but higher than in the DF-11 group. SDF rats showed similar kg, DeltaG and DeltaI compared with the CO-11 and SCO groups. However, a significantly lower kg and higher DeltaG and DeltaI were observed in SDF compared with DF-11 rats. Basal and 8.3 mmol glucose/l-stimulated insulin secretion by islets from DF-11 rats were higher than by islets from CO-11 rats. These results indicate that moderate Mg depletion for a long period may increase the secretion and sensitivity to insulin, while Mg supplementation in formerly Mg-deficient rats may prevent the increase in sensitivity and secretion of insulin.

Aspectos clínico-patológicos da intoxicação experimental por selenito de sódio em eqüinos

Abstract: Due to the numerous contradictions on selenium poisoining, and in order to improve knowledge about the clinical, pathological and toxicological aspects, experiments were performed with intramuscular injections of sodium selenite in 9 horses. Peracute, acute, subacute and chronic poisoning was reproduced; some nervous symptoms observed in acute cases were similar to those described for "blind staggers". In spite of this, the conflicting and dubious feature of this formerly described disease turns very difficult any comparison. On the other hand, the chronic poisoning was the first experimental reproduction of "alkali disease" by the parenteral route in horses. When administered as one injection, the lethal dose for sodium selenite was 1.49 mg/kg. Various clinical and pathological observations regarding the cardiovascular and nervous system, not previously mentioned in the literature for horses, are described. There have to be mentioned especially, (1) as to clinical aspects, cardiac murmurs, arrythmia, splitting of the heart sounds and convulsions, (2) regarding post-mortem findings, flattening of the cerebral gyri and increase of the liquor, and (3) concerning histopathology, lysis and necrosis of neurons in the cortex, oedema of astrocytes, as well as activation of endothelial and glia cells. It is suggested, that the degenerative-necrotic alterations in the central nervous system could be due to the oedema caused by an increase in vascular permeability through the action of the selenite.

Local abundance and regional distribution of tree species of forest fragments in Brazil: A test of models

Abstract: Patterns of local abundance and regional distribution of tree species were analyzed on three spatialscales and compared with those predicted by Hanski’s 1982 original core-satellite model, Brown’s 1984 nichebasedmodel, and Tokeshi’s 1992 model. Data were collected in seven forest fragments dispersed overapproximately 7200 km2, remnants of a former continuous forest in the south of Mato Grosso do Sul state,southwestern Brazil. Fifty-six east-west-oriented 10 m ¥ 150 m plots were randomly demarcated in thosefragments from 1994 to 1996. In each plot all trees having DBH ≥ 0.15 m were recorded and measured. Thesmallest scale was that of the fragments themselves and the greatest was that of the entire region. No evidencewas found of the bimodality predicted by Hanski’s 1982 model on any scale. On all scales, an unimodal patternwas found whose mode was on the left side (satellite mode) of the distribution. This pattern was in bestagreement with the predictions of Tokeshi’s 1992 model.

Apport des satellites géostationnaires GOES pour l'étude du climat du Mato Grosso, Brésil

Abstract: Remotely sensed measurements from geostationnary satellites GOES are used for the study of a climatologicaly bad-known area : the state of Mato Grosso in western central Brazil. Datas from the visible channel give informations on the landcover and principaly on the progression of deforestation linked to one of the greatest pioneer front of the Amazonia. Infrared measurements are used for the estimation of monthly rainfall using passive microwave images (SSM/I) for validation.