Homologous xylanases from Clostridium thermocellum: evidence for bi-functional activity, synergism between xylanase catalytic modules and the presence of xylan-binding domains in enzyme complexes.

Clostridium thermocellum produces a consortium of plant-cell-wall hydrolases that form a cell-bound multi-enzyme complex called the cellulosome. In the present study two similar xylanase genes, xynU and xynV, were cloned from C. thermocellum strain YS and sequenced.

Bacterial xylanase expression in mammalian cells and transgenic mice.

The energy which simple-stomached livestock can derive from dietary plant material is limited by the lack of plant polysaccharide degrading enzymes in their gastro-intestinal (GI) tract and the inefficient microbial fermentation of such material in their hind-gut. In poultry the non-starch polysaccharides found in cereal grains can also impair normal digestive function as they form viscous gels in the GI tract inhibiting the breakdown and absorption of nutrients. The nutrition of such livestock could, therefore, be improved by the introduction of enzymes able to degrade plant polysaccharides in the small intestine.

Stimulation of ouabain binding to Na,K-ATPase in 40% dimethyl sulfoxide by a factor from Na,K-ATPase preparations.

In 40% dimethyl sulfoxide (Me2SO) high-affinity ouabain (O) binding to Na,K-ATPase (E) is promoted by Mg2+ in the absence of inorganic phosphate (Pi) (Fontes et al., Biochim. Biophys.

Cellular responses to Plasmodium falciparum major surface antigens and their relationship to human activities associated with malaria transmission.

In Brazil, two types of activities have led to the worsening of malarial transmission in the Amazon region: prospecting/mining and agricultural settlements. In the present study, we analyze the cellular response of 52 of these individuals (14 gold-miners and 38 farmers) living within the same endemic area. Two Plasmodium falciparum major surface antigens (recombinant proteins) were used for cellular proliferative assays: circumsporozoite protein and merozoite surface protein-1.

Hepatitis B virus infection in immigrants to the southern Brazilian Amazon.

To identify epidemiological patterns and risk factors associated with hepatitis B virus (HBV) infection in the southern Brazilian Amazon, a survey was performed in the county of Terra Nova do Norte in the northern part of the state of Mato Grosso. The population consists mainly of immigrants from the southern part of Brazil, where HBV prevalence is low. A random sample (n = 783) of the population was interviewed and tested for HBV markers.

Outbreak of hepatitis B virus in recent arrivals to the Brazilian Amazon.

An outbreak of acute hepatitis cases in a small community took place 6 months after the community's arrival to the Brazilian Amazon. An epidemiological investigation was performed and included residents aged more than two years. Study subjects were interviewed and bled to test for hepatitis markers by enzyme immunoassays.

Prevalence of Helicobacter pylori infection in a rural area of the state of Mato Grosso, Brazil.

The prevalence of Helicobacter pylori infection was evaluated by ELISA in 40 children and teenagers and in 164 adults from a rural area of the State of Mato Grosso, Brazil. Antibodies to H. pylori were detected in the serum of 31 (77.

Identification of tandemly repeated type VI cellulose-binding domains in an endoglucanase from the aerobic soil bacterium Cellvibrio mixtus.

Cellulose-binding domains (CBD) play a pivotal role during plant cell wall hydrolysis by cellulases and xylanases from aerobic soil bacteria. Recently we have reported the molecular characterisation of a single-domain endoglucanase from Cellvibrio mixtus, suggesting that some cellulases produced by this aerobic bacterium preferentially hydrolyse soluble cellulosic substrates. Here we describe the complete nucleotide sequence of a second cellulase gene, celB, from the soil bacterium C.

Persistence of humoral response against sporozoite and blood-stage malaria antigens 7 years after a brief exposure to Plasmodium vivax.

The persistence of malarial antibodies was evaluated in subjects living in a rural community (in Minas Gerais State, Brazil) briefly exposed to a Plasmodium vivax malaria outbreak outside of the area in which malaria was endemic. Transmission was interrupted by treatment of all patients and their relatives and/or neighbors, although the latter had neither symptoms nor blood parasites. Antibodies to P.

Co-integration and expression of bacterial and genomic transgenes in the pancreatic and intestinal tissues of transgenic mice.

Previous studies in the mammary gland have reported the 'rescue' of poorly expressed cDNA transgenes by their co-integration with a genomic sequence specifically expressed in the mammary tissue. To determine whether a highly expressed genomic sequence co-integrated with a cDNA sequence can rescue expression in other tissues, the expression of a bacterial gene, celE', encoding endoglucanase E' (EGE'), was investigated in the pancreatic and intestinal epithelia of transgenic mice. To rescue pancreatic expression, the human growth hormone genomic sequence was co-integrated with the bacterial gene, whereas to rescue intestinal expression, the genomic sequence encoding the intestinal fatty acid binding protein was used.

Possible roles for a non-modular, thermostable and proteinase-resistant cellulase from the mesophilic aerobic soil bacterium Cellvibrio mixtus.

The widespread presence of cellulose-binding domains in cellulases from aerobic bacteria and fungi suggests the existence of a strong selective pressure for the retention of these non-catalytic modules. The complete nucleotide sequence of the cellulase gene, celA, from the aerobic soil bacterium Cellvibrio mixtus, was determined. It revealed an open reading frame of 1089 bp that encoded a polypeptide, defined as cellulase A (CelA), of M(r) 41,548.

Administration of recombinant bovine somatotropin to dairy cows for four consecutive lactations.

Effects of long-term administration of recombinant bovine somatotropin (bST) to dairy cows on complete lactational performance [60 (+/- 3) to 284 (+/- 3) d in milk (DIM)] were studied for four consecutive lactations. Beginning on d 60 (+/- 3) postpartum, Holstein cows received biweekly injections (500 mg) of bST (n = 39) or a placebo (control; n = 39) during the first lactation of the study. Cows either continued on the same treatment (n = 26) or were switched to the opposite treatment (n = 29) during the second lactation.

Short report: further evidence for hepatitis E in the Brazilian Amazon.

During an investigation of a hepatitis outbreak occurring in a small village in the Brazilian Amazon, serum samples from 16 recent hepatitis cases and 66 of their asymptomatic relatives were tested for the presence of hepatitis A, B, C, and E markers. Sanitation is poor and organized disposal of sewage is absent in the village. Two of the 16 hepatitis cases were non-A, non-B and non-C hepatitis, but their sera reacted to hepatitis E antibodies of the IgG class (anti-HEV).

[Evaluation of the program for leprosy control in counties of the State of Mato Grosso, Brazil].

Introduction: A retrospective analysis of the Program for Leprosy Control in four counties of Mato Grosso State, on the Brazil-Bolivian frontier, has been undertaken in the present study.

Population And Methods: The health care service records of all patients registered by the Programs for Leprosy Control during the period from the beginning of their activities up to 1990 inclusive were checked. Final analysis was performed by epidemiological and operational indicators for the follow-up of control activities of Leprosy Control, as defined by the World Health Organization.

Epidemiological survey of infection with hepatitis B virus in the savannah and wetlands (Pantanal) of central Brazil.

An epidemiological survey of the prevalence of hepatitis B virus (HBV) was conducted in the county of Nossa Senhora do Livramento, Mato Grosso state, central Brazil. This rural county has a largely stationary population of low socio-economic status, and is divided into savannah-type vegetation and wetland. Overall, 740 subjects aged > 9 years were selected at random, interviewed and bled so that seropositivities of various HBV markers (surface antigen and antibodies to this antigen and to core antigen) could be determined.

Cross-reactive cellular immune response to circumsporozoite proteins of Plasmodium vivax and P. falciparum in malaria-exposed individuals.

Acquired immunity against the recombinant circumsporozoite protein of P. falciparum (rPfCS) or P. vivax (rPvCS) was studied in two malarious areas of the Brazilian Amazon.

Severe falciparum malaria with hyperparasitaemia: management without exchange blood transfusion.

The risk of complication in falciparum malaria is associated with parasite load. Drug therapy alone may be insufficient, and blood exchange transfusion is indicated when more than 10% of erythrocytes are parasitized with concurrent pulmonary, renal, cerebral or haemostatic complications; without complications, when the parasitized erythrocytes exceed 30%. The successful use of conventional malaria therapy without exchange transfusion in a young woman with severe falciparum malaria is reported.

[The diagnosis of severe disseminated paracoccidioidomycosis in a bone marrow aspirate: a case report].

Acute or chronic disseminated paracoccidioidomycosis can be associated with changes in blood and bone marrow cell counts, mainly in the severe forms of this disease. However, there are few reports about the microbiological confirmation of the mycosis in bone marrow tissue. The present report describes a case of an adult patient with severe chronic multifocal paracoccidioidomycosis, whose etiological diagnosis has been done by the microscopical exam and culture fo the bone marrow aspirate.

A modular xylanase from mesophilic Cellulomonas fimi contains the same cellulose-binding and thermostabilizing domains as xylanases from thermophilic bacteria.

The xynC gene from mesophilic Cellulomonas fimi encodes a large 125 kDa modular xylanase (XYLC), consisting of six distinct functional domains. In addition to a single Family 10 catalytic domain, XYLC contains a domain homologous with the nodulation protein, NodB, from nitrogen-fixing bacteria and thermostabilizing and cellulose-binding domains found previously only in xylanases from thermophilic bacteria.

Randomized controlled trial of artesunate plus tetracycline versus standard treatment (quinine plus tetracycline) for uncomplicated Plasmodium falciparum malaria in Brazil.

A triple-blind, randomized, clinical trial was undertaken in a Brazilian Amazon region to compare the effectiveness of oral artesunate (seven days, total dose = 0.75 g) plus tetracycline (seven days, total dose = 10.5 g) (AT) and oral quinine (three days, total dose = 6 g) plus tetracycline (seven days, total dose = 10.