Avaliação farmacológica de princípios ativos presentes no chá de Erva-de-passarinho - Phoradendron latifolium (SW) Griseb

Nossos experimentos foram realizados com o intuito de avaliar informações populares que indicam que o chá de Erva-de-Passarinho é altamente vasoconstritor, assim como informações científicas referentes a outras espécies da mesma família que, segundo vários autores, apresentam efeitos hiper e hipotensores. O Phoradendron latifolium (SW) Griseb. por nós utilizado foi coletado em Maringá -PR, onde encontra-se parasitando a Figueira Branca entre outras árvores. Realizamos ensaios com o chá liofilizado de Erva-de-Passaronho sobre a motilidade do duodeno isolado de coelhos e sobre a pressão arterial de cães anestesiados com Nembutal. Observamos que o chá promoveu redução da motilidade duodenal até o máximo de 80% das contrações iniciais. Na Pressão Arterial o chá levou ao aparecimento de uma resposta bifásica, ocorrendo inicialmente uma hipertensão seguida de hipotenso que não foi bloqueada pela atropina ou propanolol. Na presença de cocaína foi suprimida a hipertensão. Podemos concluir que o efeito hipotensor não está relacionado com receptores muscarínicos ou adrenérgicos tipo β e que o efeito hipertensor seja provavelmente devido a uma substância do tipo da tiramina.

Avaliação da capacidade de fixação de fósforo pelo solo

Phosphate "fixation" is the convertion of soluble into insoluble phosphate in the soil. There are many factors conditioning phosphate fixation by soil such as reactions originating less soluble compounds (phosphates of iron, aluminum, calcium, magnesium, etc.), PO4-3 adsorption by the colloidal fraction of soils, PO4-3 absorption by the soil microflora, etc. Certain soils of the state of São Paulo (Brazil) are relatively rich in both iron and aluminum oxides. PO4-3 fixation, using P31 and P32 has been verified by researchers, specially with "Terra Roxa". The known methods for fixation evaluation are conventional as this depends on phosphate solution concentration, pH, time of contact between soil and solution, relation of sample weight to solution volume, shaking time, etc. In this experiment, the following conventional method was used: 4 g of soil were shaken for 15 minutes at 30-40 rpm, in 300 ml Erlenmeyer flask in a Wagner shaking machine, together with 100 ml of 0,03 normal phosphate solution (being 0,01 normal as PO4-3 contributed by H8PO4 and 0,02 normal as PO4-3 from KH2PO4). After shaking it was set aside for 24 hours and then filtered. Phosphate was determined in a suitable aliquot of both the original solution (blank) and the soil extract, by the vanadomolibidic-phosphoric acid method. From phosphate concentration in the blank minus phosphate concentration in the soil stract the rate of fixation by 100 g of soil was calculated. The data obtained show that "Terra Roxa" and "Terra Roxa Misturada" have a fairly high PO4-3 fixation capacity, varying from 10 to 24 milliequivalents of PO4-3 per 100 g of soil.

Ocorrência de Actinomicetos com atividade proteolitica, em um solo cultivado

Among 327 strains of Actinomycetes isolated in 1958 during the four seasons, 97,85 per cent had proteolytic activity. Most of the strains wete isolated in spring time. About the organic matter no conclusions were reached, because it was mantained constant with a average value of 4.099. So the different number of the strains was a consequence of the season. We can conclude that the Latosol red-yellow soil, from where these microorganisms were isolated, has a strong proteolytic capacity, since this reaction is very strong in a maximum limit of sixteen days during the spring season. Consequently, this soil has one of the most importante caracteristics of fertility. The role of the Actinomycetes in the soil is so important of the soil microflora.

Atividade proteolítica e amonificante de vários tipos de solo do estado de São Paulo. I. - Solo latosol vermelho amarelo, com e sem cobertura morta

Os autores estudam, no presente trabalho, um solo tipo Latosol Vermelho Amarelo, com e sem cobertura morta, em 2 profundidades diferentes. Concluiram sôbre as vantagens de se manter um solo com cobertura morta que permite um aumento da microflora total e dos elementos nutritivos, confirmado pelo pronunciado índice de atividade protelítica e amonificante do solo.

Técnica do xenodiagnostico na molestia de Chagas

O xenodiagnostico é um processo muito valioso para o diagnostico etiologico da moléstia de Chagas. Consiste em alimentar-se barbeiros normais em supótos portadores da infecção e determinar-se, depois, si eles adquirem ou não o parasitismo. Em cada região deve ser empregada, de preferência, o transmissor local mais importante. Três a seis ninfas famintas são geralmente empregadas em cada prova, devendo ficar em contacto com o doador até encherem-se completamente (15-30 minutos). Si o exame de fezes – espontaneamente eliminadas ou obtidas por punção anal – não revelar a presença de flagelados, os insetos devem ser dissecados 40 a 60 dias depois da sucção, para exame do conteúdo duodenal.

Diatomáceas de tanques do cactário do Jardim Botânico, Guanabara, Brasil

O autor analisou a microflora de três tanques situados no Cactário do Jardim Botânico, Rio de Janeiro, Guanabara. Tanque nº 1. Apresentou desenvolvimento muito intenso da microfibra nos mseses mais frios. As diatomáceas foram muito freqüentes. As espécies indicadoras de saprobidade foram as seguintes: Gomphonema gracile Ehr., pinnularia maior. (kutz) Cleve, Gomphonema parvulum (kutz) Grunow, Navicula mutica Kutz., Pinnularia borealis Ehr., Pinnularia microstauron (Ehr) Cleve, Pinnularia acrospheria Breb., Hantzschia amphioxys (Ehr) Grunow, Nitzschia palea Kutz., Eutonia pectinalis (Kutz) Rabenh. Tanque nº 2. As diatomáceas indicadoras de águas contaminadas, anotamos como segue: Eutonia pectinalis (Kutz) Rabenh., Gomphonema parvulum (kutz) Grunow, Hanstzschia amphioxys (Ehr) Grunow, Navicula mutica Kutz, Pinnularia borealis Ehr., Pinnularia maior (Kutz) Cleve, Pinnularia microstauron (Ehr) Cleve. Tanque nº 3. Foi bastante reduzida a freqüência da microflora. Comparando-o com os tanques nº 1 e 2, as diatomáceas e clorofícias observadas, mostraram-se diminuídas nos meses mais quentes. Encontramos as seguintes espécies oligosaprobias: Eunotia pectinalis (Kutz) Rabenh., Gomphonema gracile ehr., Gomphonema parvulum (Kutz) Grunow Hantzschia amphioxys (Ehr) Grunow, Pinnularia borealis Ehr., Pinnularia maior (Kutz) Cleve. Foram consideradas também as clorofíceas quanto ao regime de saprobidade do material estudado. Eutonia augusta f. crenulata Cleve-Euler e Eutonia veneris var. exsecta Clever-Euler encontradas em nossas amostras, são novas para o Brasil. Um total de 71 espécies foram determinadas de 21 coletas realizadas durante o período de 36 meses.

Helicobacter pylori in dyspeptic children and adults: endoscopic, bacteriologic and histologic correlations

Using different bacteriological (urease test, Gram staining and culture) and histological (Steiner staining and modified Giemsa staining) techniques, we searched for the presence of Helicobacter pylori in the gastric antrum of 200 dyspeptic Brazilian patients (106 females and 94 males aged 19 days to 81 years). The presence of bacteria was then correlated with the endoscopic and histological findings. H. pylori was present in 59.5 of the population studied. In Brazil, colonization occurs early, involving 37 of the dyspeptic population by 20 years of age. The presence of H. pylori in the gastric antrum was strongly associated with duodenal ulcer (P < 0.001) and a normal endoscopic examination did not exclude the possibility of colonization of the gastric antrum by H. pylori. The most sensitive test was the preformed urease test (89). We conclude that more than one diagnostic method should preferably be used for the detection of H. pylori and that the presence of H. pylori is closely correlated with active chronic gastritis (P < 0.001).

Microbial flora variations in the respiratory tract of mice

A stable microbial system in the respiratory tract acts as an important defense mechanism against pathogenic microorganisms. Perturbations in this system may allow pathogens to establish. In an ecological environment such as the respiratory tract, there are many diverse factors that play a role in the establishment of the indigenous flora. In the present work we studied the normal microbial flora of different areas of the respiratory tract of mice and their evolution from the time the mice were born. Our interest was to know which were the dominant groups of microorganisms in each area, which were the first capable of colonizing and which dominated over time to be used as probiotic microorganisms. Our results show that Gram negative facultatively anaerobic bacilli and strict anaerobic microorganisms were the last ones to appear in the bronchia, while aerobic and Gram positive cocci were present in all the areas of the respiratory tract. The number of facultative aerobes and strict anaerobes were similar in the nasal passage, pharynx instilled and trachea, but lower in bronchia. The dominant species were Streptococcus viridans and Staphylococcus saprophyticcus, followed by S. epidermidis, Lactobacilli and S. cohnii I which were present on every studied days but at different proportions. This paper is the first part of a research topic investigating the protective effect of the indigenous flora against pathogens using the mice as an experimental model.

Prevalence of cagA and vacA genes in isolates from patients with Helicobacter pylori-associated gastroduodenal diseases in Recife, Pernambuco, Brazil

Geographical differences in the prevalence of Helicobacter pylori genes and their association with disease severity have been identified. This study analyzes the prevalences of the cagA gene and alleles of the vacA gene in H. pylori-associated gastroduodenal diseases in isolates from Recife, PE, Brazil. Gastric biopsy of 61 H. pylori-positive patients were submitted to DNA extraction and gene amplification by polymerase chain reaction. Among the 61 patients, 21 suffered from duodenal ulcer (DU) and 40 from gastritis (GT). The prevalence of H. pylori strains harbouring the cagA gene was higher in the DU group (90.5%) than in the GT group (60%) (p = 0.02). The vacA gene was amplified in 56 out of 61 biopsies, of which 43 (76.8%) contained bacteria carrying the s1 allele and 13 (23.2%) the s2. However, the prevalence of the vacA s1 genotying was the same in either DU or GT group. The majority of the s1-typed strains, 39 (90.7%) out of 43, were subtype s1b. In resume there was a strong association between the H. pylori cagA+ gene and DU. However, there were no differences between the DU and GT groups in relation to the vacA s1 and s2 alleles distribution, albeit the subtype s1b was predominat.

Immunoblotting for the serodiagnosis of Helicobacter pylori infection in Brazilian patients with and without gastric carcinoma

We evaluated the performance of a commercial immunoblotting in the serodiagnosis of Helicobacter pylori infection in Brazilian patients. The presence of anti-H. pylori antibodies was also investigated in a group of 20 duodenal ulcer patients after successful treatment. One hundred and ninety one patients were studied. Among the 164 infected patients, 46 had gastric carcinoma. The duodenal ulcer patients were treated with antimicrobial drugs and the eradication of the microorganism was confirmed in all of them one month after the end of the treatment by the 13C-urea breath test. Sera were assayed for H. pylori antibodies using the Helicoblot 2.0 (Genelabs Diagnostics, Singapore). The sensitivity, specificity, positive, and negative predictive values of the test were 93.9%, 92.6%, 98.7%, and 71.4%, respectively. The sensitivity of the test was similar in patients with (93.5%) and without (95.7%) gastric carcinoma. Twenty-four months after the end of the treatment, the band of 116 kDa was still detected in one of the patients. In conclusion, the Helicoblot 2.0 is an accurate test to diagnose H. pylori infection and although it can not be employed to monitor the bacterium eradication, it may be useful for diagnosing past infection, especially in gastric carcinoma patients.

Helicobacter pylori vacA and cagA genotypes in patients from northeastern Brazil with upper gastrointestinal diseases

Helicobacter pylori causes chronic gastric inflammation and significantly increases the risk of duodenal and gastric ulcer disease and distal gastric carcinoma. In this study, we evaluated the Helicobacter pylori vacA and cagA genotypes in patients from a Brazilian region where there is a high prevalence of gastric cancer. Polymerase chain reaction (PCR) was used to investigate vacA mosaicism and cagA status in the gastric mucosa of 134 H. pylori-positive patients, including 76 with gastritis: 28 with peptic ulcer disease and 30 with gastric cancer. The s1m1 variant was the predominant vacA genotype observed, whereas the s1 allele was more frequently observed in patients with more severe diseases associated with H. pylori infection [p = 0.03, odds ratio (OR) = 5.72, 95% confidence interval (CI) = 1.15-38.60]. Furthermore, all of the s1 alleles were s1b. Mixed vacA m1/m2 strains were found more frequently in patients with gastric cancer and a cagA-positive status was significantly associated with gastric cancer (p = 0.016, OR = 10.36, 95% CI = 1.35-217.31). Patients with gastric cancer (21/21, 100%, p = 0.006) or peptic ulcers (20/21, 95%, p = 0.02) were more frequently colonised by more virulent H. pylori strains compared to gastritis patients (41/61, 67.2%). In conclusion, in the northeastern of Brazil, which is one of the regions with the highest prevalence of gastric cancer in the country, infection with the most virulent H. pylori strains, carrying the cagA gene and s1m1 vacA alleles, predominates and is correlated with more severe H. pylori-associated diseases.

Tannin-tolerant bacteria from crossbred Holstein x Zebu cows

The objective of this work was to isolate and characterize tannin-tolerant ruminal bacteria from crossbred Holstein x Zebu cows fed a chopped mixture of elephant grass (Pennisetum purpureum), young stems of "angico-vermelho" (Parapiptadenia rigida), and banana tree (Musa sp.) leaves. A total of 117 bacteria strains were isolated from enrichment cultures of rumen microflora in medium containing tannin extracts. Of these, 11 isolates were able to tolerate up to 3 g L-1 of tannins. Classical characterization procedures indicated that different morphological and physiological groups were represented. Restriction fragments profiles using Alu1 and Taq1 of 1,450 bp PCR products from the 16S rRNA gene grouped the 11 isolates into types I to VI. Sequencing of 16S rRNA PCR products was used for identification. From the 11 strains studied, seven were not identifiable by the methods used in this work, two were strains of Butyrivibrio fibrisolvens, and two of Streptococcus bovis.

Produção de isomaltulose, um substituto da sacarose, utilizando glicosiltransferase microbiana

Isomaltulose, a functional isomer of sucrose, is a non-cariogenic reducing disaccharide; has a low glycemic index; selectively promotes growth of beneficial bifidobacteria in the human intestinal microflora; and has greater stability than sucrose in some foods and beverages. Isomaltulose is a nutritional sugar that is digested more slowly than sucrose, and has health advantages for diabetics and nondiabetics. Immobilization techniques, especially entrapment of the cells, are widely used for conversion of sucrose into isomaltulose. Immobilization offers advantages such as minimum downstream processing, continuous operation and reusability of cells. Isomaltulose is currently considered to be a promising sugar substitute.

Resistência natural de nove madeiras do semi-árido brasileiro a fungos causadores da podridão-mole

O objetivo desta pesquisa foi avaliar a resistência de nove madeiras de ocorrência no semi-árido brasileiro a fungos de podridão-mole, em condições de laboratório. As madeiras estudadas foram algaroba (Prosopis juliflora), angico (Anadenanthera colubrina var. cebil), aroeira (Myracrodruon urundeuva), braúna (Schinopsis brasiliensis), cássia (Senna siamea), craibeira (Tabebuia aurea), cumaru (Amburana cearensis), pau-d'arco (Tabebuia impetiginosa) e pereiro (Aspidosperma pyrifolium). De cada espécie foram retirados corpos-de-prova de 3,0 x 1,5 x 0,5 cm, com a maior dimensão no sentido das fibras, em quatro posições na direção medula-casca do tronco. As amostras permaneceram por 120 dias sob a ação da microflora natural existente em solo orgânico. A resistência ao apodrecimento da aroeira, braúna e cássia não foi afetada pela posição na direção medula-casca, não esteve relacionada à densidade das madeiras ensaiadas. As madeiras de aroeira e braúna (cerne), pereiro e pau-d'arco apresentaram melhor desempenho. A resistência natural não esteve associada à concentração de extrativos solúveis em água quente.

Resistência natural de nove madeiras do semiárido brasileiro a fungos xilófagos em simulares de campo

Os objetivos desta pesquisa foram avaliar a resistência de nove madeiras de ocorrência no semiárido brasileiro a fungos xilófagos em simuladores de campo e relacionar a resistência natural com a densidade e teor de substâncias extraídas em água quente. As madeiras estudadas foram algaroba (Prosopis juliflora), angico-vermelho (Anadenanthera colubrina var. cebil), aroeira (Myracrodruon urundeuva), braúna (Schinopsis brasiliensis), cássia (Senna siamea), craibeira (Tabebuia aurea), cumaru (Amburana cearensis), pau-d'arco (Tabebuia impetiginosa) e pereiro (Aspidosperma pyrifolium). De cada espécie foram retirados corpos-de-prova de 0,5 x 1,5 x 15,0 cm, com a maior dimensão na direção das fibras, em quatro posições na direção medula-casca do tronco. As amostras permaneceram por 180 dias sob ação da microflora natural existente em três tipos de solos: de floresta, de uso agrícola e com gramíneas. Em todas as madeiras ensaiadas, a resistência ao apodrecimento foi afetada pela posição na direção medula-casca. Apenas na aroeira a resistência da madeira esteve associada à sua densidade e à quantidade de extrativos solúveis em água quente. A resistência das madeiras de algaroba, angico, craibeira e pau-d'arco não esteve associada à densidade nem ao teor de extrativos. O alburno foi a posição mais atacada em todos os solos analisados. Entre os solos testados, o de uso agrícola apresentou menos atividade biológica, deteriorando menos as madeiras testadas.