Diferenças entre as dimensões das fibras nos anéis de crescimento determinados no D. A. P. e em níveis diferentes do fuste de árvores adultas de Eucaliptus saligna Smith

Neste trabalho apresentamos os resultados dos estudos das diferenças entre as dimensões (comprimento, diâmetro e espessura) das fibras lenhosas nos anéis de crescimento (da periferia ao centro do fuste), determinadas ao nível do D. A. P. (distância a altura do peito) e em diferentes níveis (10%, 20% e 30% da altura do fuste) de árvores adultas de Eucalyptus saligna Smith, tendo como objetivo verificar se em nossas condições, as amostras tomadas apenas no D. A. P. representam o fuste da árvore.

Characterization of rotavirus P genotypes circulating among paediatric inpatients in Northern Brazil

Between November 1992 and August 1993, twenty-eight rotavirus-positive stool samples obtained from paediatric inpatients in Belém, Brazil, aged less than four years, were tested by RT-PCR to determine the P genotype specificities. With the exception of 7 non-diarrhoeic children, all patients were either diarrhoeic at admission or developed diarrhoea while in hospital. Rotavirus strains with the gene 4 alleles corresponding to P1B[4] and P1A[8] types (both of which bearing G2 specificity) predominated, accounting for 78.6% of the strains. While only one P2A[6] type strain - with (mixed) G1 and 4 type specificities - was detected, the gene 4 allele could not be identified in 4 (14.3%) of the strains. Most (81%) of the specimens were obtained from children during their first 18 months of life. Rotavirus strains bearing single P1B[4] type-specificity were identified in both diarrhoeic (either nosocomial, 28.6% or community-acquired diarrhoea, 28.6%) and non-diarrhoeic (42.8%) children. P1A[8] gene 4 allele, on the other hand, was detected only among diarrhoeic children, at rates of 57.1% and 42.9% for nosocomial- and- community acquired diarrhoea, respectively. Mixed P1A[8],1B[4] type infection was identified in only one case of community-acquired diarrhoea.

Ensaio de espaçamento com Caroba - Jacaranda copaia (Aubl.) D. Don. Bignontaceae

RESUMONa Estação Experimental de Silvicultura Tropical (E.E.S.T.) do INPA-Manaus, foi instalado no ano de 1980 um experimento para Caroba em três (3) espaçamentos. As avaliações da sobrevivência, altura total e comercial, D.A.P., área basal e volume realizadas no ano de 1989, nove anos após o plantio, indicaram que o menor espaçamento (2,0 X 3,0 m) apresentou maior volume de madeira útil em função do grande número de árvores vivas (70,98%) com altura comercial média de (11,76 m) e D.A.P. médio aritmético de 22,73 cm. Após o 5º ano de plantio, foi observado que um número significativo de árvores apresentaram copas cloróticas, seguida da queda das folhas e consequente morte das árvores, fato este, possivelmente relacionado com o estado nutricional das árvores deste experimento.

Comportamento do girassol quando cultivado em área tratada com o herbicida 2,4-D¹

Com o objetivo de determinar o período adequado de semeadura da cultura do girassol (Helianthus annuus), em relação à aplicação de 2,4-D, foi realizado um experimento em condições de campo da área experimental da Embrapa Soja, Londrina-PR, durante o ano agrícola 1995/96. Os tratamentos estabelecidos foram doses do herbicida 2,4-D (0,0, 536 e 1.005 g e.a. ha-1 ) e épocas de semeadura da cultura. Dessa forma, a semeadura foi realizada um dia antes da aplicação do produto (-1 dia), no dia da aplicação (0 dia) e a 1, 4, 7, 10 e 13 dias depois da aplicação do herbicida. Os resultados indicaram que o girassol sofreu injúrias mais severas nas três primeiras épocas de semeadura (-1, 0 e 1). Aumentando o tempo entre a aplicação das doses do herbicida e a semeadura do girassol, observaram-se menores danos causados à cultura. O experimento permitiu concluir que áreas tratadas com o 2,4-D nas doses de 536 e 1.005 g e.a. ha-1 podem ser cultivadas com girassol, desde que se mantenha um intervalo mínimo de quatro dias entre a aplicação do herbicida e a sua semeadura.

Eficácia do carfentrazone-ethyl no controle de plantas aquáticas latifoliadas em caixas-d'água

Atualmente, alguns herbicidas estão sendo desenvolvidos para o controle de plantas daninhas aquáticas. O objetivo deste trabalho foi avaliar a eficácia do carfentrazone-ethyl em ambiente aquático para o controle pós-emergente de aguapé, alface-d'água e salvínia. O trabalho foi desenvolvido em caixas-d'água, no período de julho a setembro de 2004, no NUPAM - FCA/UNESP, em Botucatu. O delineamento experimental adotado foi o de blocos ao acaso, com sete tratamentos e quatro repetições, sendo as unidades experimentais constituídas pelas caixasd'água. Os tratamentos foram os seguintes: testemunha sem herbicida; Aurora 400 CE (75, 150 e 300 mL ha-1); Roundup (3,0 L ha-1), Aurora 400 CE + Roundup (75 mL + 3,0 L ha-1) e Aurora 400 CE + Arsenal N.A. (75 mL + 2,0 L ha-1). Observou-se que o tratamento Aurora 400 CE (300 mL ha-1) é altamente eficaz no controle de alface-d'água (Pistia stratiotes); o tratamento Roundup (3,0 L ha-1) é altamente eficaz no controle de aguapé (Eichhornia crassipes); o tratamento Aurora 400 CE + Roundup (75 mL + 3,0 L ha-1) é eficaz no controle de aguapé (E. crassipes), alface-d'água (P. stratiotes) e salvínia (Salvinia auriculata); e o tratamento Aurora 400 CE + Arsenal (75 mL + 2,0 L ha-1) é eficaz no controle de aguapé (E. crassipes) e alface-d'água (P. stratiotes). A mistura Aurora 400 CE + Roundup (75 mL + 3,0 L ha-1) apresentou-se viável e foi o único tratamento eficaz no controle das três espécies estudadas.

Satisfacción con el empleo de extensionista rural: un estudio cualitativo en Caldas, Colombia

Como aporte al posicionamiento de la extensión rural como objeto multidimensional de estudio, se analizan las valoraciones realizadas por extensionistas rurales acerca de situaciones inherentes a su experiencia cotidiana de trabajo, seguido de la identificación de factores de satisfacción/insatisfacción laboral. En consonancia con la esencia cualitativa del estudio, la información se generó a partir de entrevistas semiestructuradas a 23 extensionistas rurales adscritos las Unidades Municipales de Asistencia Técnica (UMATA) de cinco municipios del departamento de Caldas, Colombia. El análisis de discurso permitió identificar ocho factores: a) gusto por la profesión ejercida, b) posibilidades de proyección social, c) alcance y visualización de logros, d) reconocimiento público, e) posibilidades de ascenso, f) posibilidades de aprendizaje continuo, g) autonomía, y h) estabilidad laboral. Se concluye que desconocer el estado emocional de los extensionistas hacia el trabajo produce el riesgo de crear o conservar escenarios que limiten el compromiso con la labor social realizada y el mantenimiento de la vocación extensionista.

Relação entre prevalência, incidência e duração média da doença

Foi apresentada uma demonstração da fórmula Pt = I d onde P t = prevalência instantânea; I = Incidência; e d duração média da doença para a situação de estabilidade de doença.

Reinfections and rotavirus serotypes in Belém, Brazil

Repeated infections involving different rotavirus serotypes were detected in four children living in Belém, who were followed up since birth to three years of age. In one child (Reg. 23.983) three successive symptomatic infections (one of them associated with serotype 2) were noted: the first, at four months of age, the second at 20 months and the third at 27 months. Another child had two subsequent infections, the first one by rotavirus serotype 1, and the second by a not identified rotavirus serotype. In this case two episodes of rotavirus-related diarrhoea were recorded, occurring eight months apart. Apparent infections were detected on two occasions involving the same child (Reg. 24.004), the first being associated with serotype 1, and the second with serotype 2. The fourth child (Reg. 24.097) had two successive infections by not determined rotavirus serotypes, without clinical manifestations; the first occurred at 24 months and the second at 28 months.

Nutritional status in relation to the efficacy of the rhesus-human reassortant, tetravalent rotavirus vaccine (RRV-TV) in infants from Belém, Pará State, Brazil

The rhesus-human reassortant, tetravalent rotavirus vaccine (RRV-TV) was licensed for routine use in the United States of America but it was recently withdrawn from the market because of its possible association with intussusception as an adverse event. The protective efficacy of 3 doses of RRV-TV, in its lower-titer (4 x 10(4) pfu/dose) formulation, was evaluated according to the nutritional status of infants who participated in a phase III trial in Belém, Northern Brazil. A moderate protection conferred by RRV-TV was related to weight-for-age Z-scores (WAZ) greater than -1 only, with rates of 38% (p = 0.04) and 40% (p = 0.04) for all- and- pure rotavirus diarrhoeal cases, respectively. In addition, there was a trend for greater efficacy (43%, p = 0.05) among infants reaching an height-for-age Z-score (HAZ) of > -1. Taking WAZ, HAZ and weight-for-height Z-score (WHZ) indices <= -1 together, there was no significant protection (p > 0.05) if both placebo and vaccine groups are compared. There was no significant difference if rates of mixed and pure rotavirus diarrhoeal cases are compared in relation to HAZ, WAZ and weight-for-height Z-score (WHZ) indices. Although a low number of malnourished infants could be identified in the present study, our data show some evidence that malnutrition may interfere with the efficacy of rotavirus vaccines in developing countries.

Rotavirus serotypes and electropherotypes identified among hospitalised children in São Luís, Maranhão, Brazil

During June 1997-June 1999 rotavirus infection was screened in infants aged up to 2 years and hospitalised with acute diarrhoea in São Luís, Northeastern Brazil. Altogether, 128 stool samples were collected from diarrhoeic patients and additional 122 faecal specimens from age- and- temporal matched inpatients without diarrhoea were obtained; rotavirus positivity rates for these groups were 32.0% (41/128) and 9.8% (12/122), respectively (p < 0.001). Both electropherotyping and serotyping could be performed in 42 (79.2%) of the 53 rotavirus-positive stool samples. Long and short electropherotypes were detected at similar rates - 38.1% and 40.5% of specimens, respectively. Overall, a G serotype could be assigned for 35 (83.3%) of specimens, the majority of them (66.7%) bearing G1-serotype specificity. Taking both electropherotypes and serotypes together, G1 rotavirus strains displaying long and short RNA patterns accounted for 30.9% and 19.0% of tested specimens, respectively; all G2 strains had short electropherotype. Rotavirus gastroenteritis was detected year-round and, in 1998, the incidence rates tended to be higher during the second semester than in the first semester: 45.2% and 26.1% (p = 0.13), respectively. Rotavirus infections peaked at the second semester of life with frequencies of 30.1% and 13.5% for diarrhoeic children and controls, respectively. While the six rotavirus strains bearing G2-type specificity were circulating throughout the whole study period, G1 serotypes (n = 27) emerged as from June 1998 onwards, 20 (74.1%) of which clustering in 1998. These data underscore the importance of rotaviruses in the aetiology of severe infantile gastroenteritis in Northeastern Brazil and sustain the concept that a future vaccine should confer protection against more than one serotype.

Pattern of acquisition of rotavirus antibody in children followed up from birth to the age of three years

Nine hundred and forty-eight serum samples from 83 children living in Belem, Brazil, collected'within their first three years of life, were testedfor the presence of group- specific rotavirus-antibody by an enzyme-linked immunosorbent assay (ELISA) blocking-test. Passively transferred maternal antibody lasted about two and half months; subsequentely, low levels of rotavirus antibody started to appear at seven months, reaching a peak at eleven months of age. From one year onwards positivity gradually increased, reaching highest values at 34 months of life. Individual responses were examined in sera from 61 children who were followed up since birth to three years of age: 38 (62,3%) ofthem developed a long-term immunity following first infection; eleven (18.0%) children developed a short-term immunity after first infection by rotavirus; seven (11.5%) had no antibody response within their first three years of life; and 5 (8.2%) showed positive antibody response from birth to three years old.

Trypanosoma cruzi in marsupial didelphids (Philander frenata and Didelhis marsupialis): differences in the humoral immune response in natural and experimental infections

Philander frenata and Didelphis marsupialis harbor parasitism by Trypanosoma cruzi without developing any apparent disease and on the contrary to D. marsupialis, P. frenata maintains parasitism by T. cruzi II subpopulations. Here we compared the humoral immune response of the two didelphids naturally and experimentally infected with T. cruzi II group, employing SDS-PAGE/Western blot techniques and by an Indirect immunofluorescence assay. We also studied the histopathological pattern of naturally and experimentally infected P. frenata with T. cruzi. P. frenata sera recognized more antigens than D. marsupialis, and the recognition pattern did not show any change over the course of the follow up of both didelphid species. Polypeptides of 66 and 90kDa were the most prominent antigens recognized by both species in the soluble and enriched membrane fractions. P. frenata recognized intensely also a 45kDa antigen. Our findings indicate that: 1) there were no quantitative or qualitative differences in the patent or subpatent phases in the recognition pattern of P. frenata; 2) the significant differences in the recognition pattern of parasitic antigens by P. frenata and D. marsupialis sera suggest that they probably "learned" to live in harmony with T. cruzi by different strategies; 3) although P. frenata do not display apparent disease, tissular lesions tended to be more severe than has been described in D. marsupialis; and 4) Both didelphids probably acquired infection by T. cruzi after their evolutionary divergence.

Risk factors, biochemical markers, and genetic polymorphisms in early coronary artery disease

OBJECTIVE: To assess the risk factors, lipid and apolipoprotein profile, hemostasis variables, and polymorphisms of the apolipoprotein AI-CIII gene in early coronary artery disease (CAD). METHODS: Case-control study with 112 patients in each group controlled by sex and age. After clinical evaluation and nutritional instruction, blood samples were collected for biochemical assays and genetic study. RESULTS: Familial history of early CAD (64 vs 39%), arterial hypertension (69 vs 36%), diabetes mellitus (25 vs 3%), and previous smoking (71 vs 46%) were more prevalent in the case group (p<0.001). Hypertension and diabetes were independent risk factors. Early CAD was characterized by higher serum levels of total cholesterol (235 &plusmn; 6 vs 209 &plusmn; 4 mg/dL), of LDL-c (154 &plusmn; 5 vs 135 &plusmn; 4 mg/dL), triglycerides (205 &plusmn; 12 vs 143 &plusmn; 9 mg/dL), and apolipoprotein B (129 &plusmn; 3 vs 105 &plusmn; 3 mg/dL), and lower serum levels of HDL-c (40 &plusmn; 1 vs 46 &plusmn; 1 mg/dL) and apolipoprotein AI (134 &plusmn; 2 vs 146 &plusmn; 2mg/dL) [p<0.01], in addition to an elevation in fibrinogen and D-dimer (p<0.02). The simultaneous presence of the rare alleles of the APO AI-CIII genes in early CAD are associated with hypertriglyceridemia (p=0.03). CONCLUSION: Of the classical risk factors, hypertension and diabetes mellitus were independently associated with early CAD. In addition to an unfavorable lipid profile, an increase in the thrombotic risk was identified in this population. An additive effect of the APO AI-CIII genes was observed in triglyceride levels.