Efeito de alguns curares naturais e da d-Tubocurarina retardando o tempo de coagulação e o tempo de protombina do sangue humano

In this paper the author points out to a old question of about 200 years ago in wich two kinds of opinions were discussed. BANCROFT and FONTANA in one hand atributes for the Indian arrow poison (curare) the propriety of uncoagulate the blood, and C. BEBNAHDJ, B. RODRIGUES and others made an contradictory opinion upon this subject. In our experiments, we utilized 4 curares samples from indians who lives near the Brazilian border at Colombia, the famous Ticunas poison, and the alkaloid d-Tubocurarine. These poisons were added in form of emulsion in saline to the blood and blood plasma in order to perform two kinds of experiments. In one serie of experiments we observed the effect of curare on human blood coagulation time according to LEE-WHITE technic puting 0.5 ml of the various poisons emulsions previously into the tube. By this method, we have found that the emulsion containing 0.1 g of the poison in 10 ml saline was the most effective (Table II), therefore we used this curare emulsion concentration in the other serie of experiments, in which we tested the action of these venoms on the human blood plasma prothrombins time, (Quick Technic) adding 0.1 ml of the saline poison emulsion to each 0.1 ml of human blood plasma. Results from these experiments can be seen on Table II. These experiments we have tried on one sample of human blood plasma plus the differents curares samples; and in another opportunity four samples of human blood plasma were tried with the curare from Ticunas indians (the most effective in this respect). Results from these experiments may be seen on Table III. All the poison tried in our experiments was previously tested on toads legs (B. crucifer) to verify his curares action. All times obtained with the experiments above, show highly significant results (P<001) when compared with the blood and blood plasma mixed with in the same volume of saline. Our results, point out that BANCROFT and FONTANA views upon the effect of curare on blood clothing time were correct. Curares enhance the blood clothing time "in vitro". But, in other hand, the work in that matter by NESI (6), and TISTHOUND (7) showing that d-Tubocurarine had no significant effect on blood clothing time of man and dogs "in vivo", made possible to conclude that the observations of C. BERNARD, B. RODRIGUES and others were also true. These discordance of opinions, we believe, may result as BANCROFT and FONTANA researches, were wade "in vitro" whereas C. Bernard, B. Rodrigues and others performed their experiments "in vivo".

Nematodes of Amazonian birds, with a description of Hoazinstrongylus amazonensis n.gen.n.sp. (Trichostrongylidae, Libyostrongylinae)

During recent studies of the parasites of birds from the Amazonian Regio, the following nematodes were recovered: Hoazinstrongylus amazonensis n.gen.n.sp. from Opisthocomus hoazin (Muller, 1776); Ascaridia columbae (Gmel., 1790) Travassos, 1913, from Leptotila r. rufaxilla (Richard & Bernard, 1712) representing a new host record; Inglisakis ibanezi Freitas, Vicente & Santos, 1969, Cyrnea (C.) semilunaris (Molin, 1860) Seurat, 1914 and Thelazia digitata Travassos, 1918. A compelte description is restrained to the new genus and new species here proposed. The other known and well described species are listed and accounted.

Development of an immunoenzymatic assay using a monoclonal antibody against a 50-kDa catabolite from the P126 Plasmodium falciparum protein to the diagnosis of malaria infection

The WHO criterion of defering any donation of blood by a confirmed case of malaria for three years after cessation of therapy can not be applied in areas where malaria in endemic. For this reason we developed an immunoenzymatic assay for the detection of plasmodial antigens for blood screening in malararial endemic areas. So, we tested sera from 191 individuals. Among patients with active disease 100% of the cases of Plasmodium falciparum or mixed infections and 91.7% of those with P. vivax were positive for the presence of plasmodial antigens. The lower parasitaemia detected was 0.0003% for P. vivax malária. When the frequency of positive circulating malarial antigens was evaluated among asymptomatic and symptomatic individuals with negative TBS, positive results were found in respectively 38.7% and 17.7% of the individuals studied in the 30 days after confirmed malaria attack. Data provide by these assays have shown that ELISA seemed to be more sensitive than parasitological examination for malaria diagnosis. This test by virtue of its high sensivity and the facilities in processing a large number of specimens, can prove to be useful in endemic areas for the recognition of asymptomatic malaria and screening of blood donors.

Human parvovirus B19 infection and hydrops fetalis in Rio de Janeiro, Brazil

Formalin-fixed paraffin embedded lung and liver tissue from 23 cases of non immune hydrops fetalis and five control cases, in which hydrops were due to syphilis (3) and genetic causes (2), were examined for the presence of human parvovirus B19 by DNA hybridisation. Using in situ hybridisation with a biotynilated probe one positive case was detected. Using 32P-labelled probes in a dot blot assay format, five further positives were obtained. These were all confirmed as positive by a nested polymerase chain reaction assay. Electron microscopy revealed virus in all these five positive cases. The six B19 DNA positive cases of hydrops fetalis were from 1974, 1980, 1982, 1987 and 1988, four of which occurred during the second half of the year, confirming the seasonality of the disease.

Reverse transcription-polymerase chain reaction construction of plasmid-based, full-length cDNA libraries from Leishmania infantum for in vitro expression screening

We describe a streamlined reverse transcription-polymerase chain reaction methodology for constructing full-length cDNA libraries of trypanosomatids on the basis of conserved sequences located at the 5' and 3'ends of trans-spliced mRNAs. The amplified cDNA corresponded to full-length messengers and was amenable to in vitro expression. Fractionated libraries could be rapidly constructed in a plasmid vector by the TA cloning method (Invitrogen). We believe this is useful when there are concerns over the use of restriction enzymes and phage technology as well as in cases where expression of proteins in their native conformation is desired.

Seroprevalence of Trypanosoma cruzi infection in French Guiana

A survey was carried out on 1487 individuals to assess the seroprevalence of Trypanosoma cruzi infection in French Guiana. The overall prevalence of T. cruzi specific IgG was 0.5%. In multivariate analysis, residence in areas where housing is favorable for the presence of triatomine bugs was the only factor associated with the presence of T. cruzi antibodies. These results have implications for public health since blood donors are not routinely screened for T. cruzi infection in French Guiana.

Whole-cell antigenicity data support sequence-based kinetoplastid taxonomy

Early immunological data, obtained by immunodiffusion and immunoelectrophoresis, on the whole-cell antigenicity of kinetoplastid protozoa were retrieved and used to construct a dendrogram of antigenic distances. Remarkably, they supported the same taxonomic conclusions as analyses based on DNA and protein sequence data.

Avaliação de atributos físicos e estoques de carbono e nitrogênio em solos com queima e sem queima de canavial

O Brasil é o maior produtor mundial de cana-de-açúcar, de modo que mudanças no seu manejo podem afetar sobremaneira o ambiente. Há quase um século, as pesquisas são baseadas em áreas sob queima da biomassa foliar (palhada) dessa cultura. Mas a supressão da queimada é um novo conceito no manejo da palhada. Portanto, há poucos resultados sobre o manejo desse material. O objetivo do estudo foi comparar teores de C e N e estabilidade de agregados e densidade do solo nos manejos com queima (Cq) e sem queima (Sq) da palhada. Estudou-se um solo argiloso (Latossolo Vermelho = LVdf) e dois solos arenosos (Argissolo Vermelho-Amarelo = PVAd e Neossolo Quartzarênico = RQo) submetidos aos manejos Cq e Sq. Em cada solo foi estabelecida uma área experimental em blocos ao acaso com seis repetições. A quantidade de palhada adicionada em três colheitas foi 40 t ha-1 em matéria seca e, um ano após a terceira colheita, a acumulação foi 4,5 t ha-1 (11 %) no LVdf e 3,6 t ha-1 (9 %) no RQo. Isso representou 1,60 e 1,35 t ha-1 em C e 0,022 e 0,021 t ha-1 em N, respectivamente. Houve aumento no teor de C nos solos Sq, concorrendo em seqüestro de C na camada 0-20 cm de 6,3 e 4,7 t ha-1, respectivamente em LVdf e RQo. Assim, a taxa de seqüestro de C no compartimento cobertura + solo (0-20 cm) foi de 2,63 e 2,02 t ha-1 ano-1 no LVdf e RQo, respectivamente. Também houve aumento no teor de macroagregados em solos Sq comparados a solos Cq: 814 e 693 g kg-1 no LVdf e 516 e 420 g kg-1 no RQo. Ocorreu compactação superficial no PVAd e RQo em decorrência do uso de máquina colhedora em solo Sq. Nos solos estudados, o manejo sem queima da cana-de-açúcar resultou em melhorias nas propriedades dos solos e promoveu seqüestro de C e N na cobertura e nas camadas superficiais dos solos.

Práticas rurais de leitura: dos acervos aos modos de ler

O artigo discute questões relativas à prática de leitura de seis leitores assíduos oriundos do meio rural, dando ênfase à análise dos acervos particulares e aos meios e modos de ler. A abordagem que se estabelece advém do resultado de uma pesquisa realizada com base nos pressupostos teóricos vinculados à história da leitura e nas proposições do historiador Roger Chartier, e aos conceitos da sociologia da leitura e da cultura discutidos por Bernard Lahire. Através da análise dos acervos particulares, classificados a partir das esferas de circulação social, identificaram-se os temas de maior interesse dos leitores, assim como modos de ler que revelam práticas de leituras silenciosas e extensivas.

Identificação de resistência genética do cacaueiro à podridão-parda

O objetivo deste trabalho foi comparar métodos de caracterização da resistência do cacaueiro (Theobroma cacao) à podridão-parda (Phytophthora palmivora). Foram estudados os métodos escala de notas, índice de intensidade de infecção e índice de doença. Discos foliares de 103 genótipos receberam 0,2 mL de uma suspensão com 3x10(5) zoósporos de P. palmivora por mililitro, e os sintomas foram avaliados pelos três métodos. Foram realizadas três avaliações (repetições) por genótipo, cada uma composta por 20 discos. O método do índice de doença foi o mais eficiente em caracterizar a resistência de genótipos de cacaueiro a P. palmivora.