Physical properties of films based on pectin and babassu coconut mesocarp.

The objective of this research was to study the physical properties, water sorption, thermal and structure of films made from citrus pectin (CP), babassu coconut mesocarp (BCM) and glycerol (G). Seventeen formulations were prepared according to a central compound rotational design combining different proportions of the materials and evaluating the films produced according to their moisture contents, solubility, thicknesses and water vapor permeability. The results showed a direct relationship between the composition of the film and each physical property, providing films with unique mechanical characteristics and barrier properties. In the second phase, the films were reformulated, maintaining the proportions of CP and BCM constant and altering the G content. The results showed films with permeable structures, thus favoring the use of high drying temperatures (up to 70 °C) for the confection of films, without altering their physical and structural properties.

1-Methyl-2-pyrrolidone: from exfoliating solvent to a paramagnetic ligand.

When 1-methyl-2-pyrrolidone molecule (1m2p) interacts with the T[Ni(CN)4] layer, its carbonyl π bond homolytically disrupts and forms a coordination bond at the axial positions for the metal T, and hybrid inorganic-organic solids of formula unit T(L)2[Ni(CN)4], with T = Mn, Co, Ni, are obtained. The formed solids crystallize with a monoclinic unit cell in the C2/m space group where the metal T is found with octahedral coordination to four N ends of CN groups from a given layer and to two oxygen atoms from the organic ligands, while the inner metal (Ni) preserves its square planar coordination. In the interlayer region, the organic molecules achieve unusual planarity and are stacked through dipole-dipole interactions in a head-to-tail configuration to form a chain of molecular pillars. From such interactions, 3D pillared hybrid solids result. Upon the charge donation to the metal by oxygen atom from 1m2p, the latter becomes an organic radical whose SOMO frontier orbital has a strong π character, associated with an essentially planar structure. The unpaired electron is delocalized between neighboring C and N atoms at the ligand ring plane, and it is featured by an outstanding broad absorption band in the near-IR region. For Ni, the metal of highest polarizing power within the considered series, the existence of π overlapping interaction between organic ligand molecules leads to ferromagnetic ordering at low temperature, with TC = 10.07 K. For Mn and Co, related to the lower metal electron-withdrawing ability, the materials maintain the weak antiferromagnetic character resulting from the interaction between T metals in the layer -T-N≡C-Ni-C≡N-T- chains.

Ocorrência de Salmonella spp. e Staphylococcus coagulase positiva em pescado no nordeste, Brasil / Occurrence of Salmonella spp. and coagulse positive Staphylococcus in fish and crustaceans in the northeast of Brazil

O presente estudo foi conduzido com o objetivo de verificar a ocorrência de Salmonella spp. e Staphylococcus coagulase positiva em pescados e crustáceos provenientes da região nordeste no período de fevereiro de 2004 a dezembro de 2005. Das 143 amostras de peixes e crustáceos (camarão congelado e cauda de lagosta), 5 (3,5%) apresentaram-se positivas para Salmonella spp. Enquanto nas amostras de peixe e cauda de lagosta a contagem de Staphylococcus coagulase positiva foi < 1,0 x 102UFC/g estimado, nas amostras de camarão congelado, em duas a contagem foi 1,0 x 101UFC/g estimado e em uma 2,6 x 101UFC/g estimado, as demais <1,0 x 101UFC/g estimado. Com base nos resultados obtidos conclui-se que as amostras analisadas apresentaram baixos níveis de ocorrência de Salmonella spp. e Staphylococcus coagulase positiva e que, mesmo com estes baixos índices, constantemente deve-se buscar uma melhora na qualidade dos produtos da pesca, melhora esta que passa pelo treinamento constante em boas práticas de fabricação, procedimentos padrões de higienização e análise de perigos e pontos críticos de controle do pessoal que trabalha na pesca ou em fazendas de criação de camarão, bem como dos funcionários das indústrias.

The present study was carried out to evaluate the occurrence of Salmonella spp. and coagulase-positive Staphylococcus in fish and crustaceans from the Brazilian Northeast. Five out of the 143 samples (3.5%) were positive for Salmonella spp. While none of the fish and lobster tail samples were positive for coagulase positive Staphylococcus, two shrimp samples presented an estimated count of 1.0 x 101colony forming units per gram (cfu/g), and one presented 2.6 x 101 cfu/g. The results showed a low level of Salmonella and coagulase positive Staphylococcus occurrence. However, even with these low levels of bacterial numbers in fish and crustaceans we should search look for an improvement in their quality. This improvement should be associated to constant training for good manufacturing practice, a standard procedure of hygiene and analysis of hazards and critical control points related to employees that work as fishers or on shrimp farms, as well as those working in the industry as a whole.

Characterisation of lymphocyte response and cytokine patterns in patients with dengue fever.

It is believed that the pathogenesis of dengue is generated by a deregulation of the immunological response. Dengue virus-infected monocytes/macrophages are likely to secrete monokines, which play a role in clinical features observed in patients with dengue haemorrhagic fever or dengue shock syndrome. This is a report on a study on 45 individuals presenting clinical and laboratory characteristics of dengue virus infection. During the acute phase of infection, immunophenotyping of peripheral mononuclear leukocytes was carried out in 19 patients and demonstrated a reduced frequency of CD2+ lymphocytes and their CD4+ and CD8+ subsets. Normal ratios were recovered during convalescence. Also, during the acute phase, mononuclear cells proliferated poorly in response to mitogens and dengue antigens as detected by incorporation of radiolabeled thymidine. During convalescence the lymphoproliferative response was re-established. In addition, the presence of circulating cytokines was investigated in the plasma of the same 45 patients. Concentrations of tumour necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), interleukin-10 (IL-10) and soluble tumor necrosis factor receptor (sTNF-Rp75) were found to be significantly elevated in patients when compared to normal controls. The increase in TNF-alpha was correlated with haemorrhagic manifestations and the increase in IL-10 with platelet decay. The data demonstrate that during the acute phase of dengue infection subsets of T lymphocytes are depressed in terms of both rate and function and provide evidence that circulating pro-inflammatory cytokines, such as TNF-alpha, are important in the pathogenesis and severity of dengue. IL-10 may be downregulating lymphocyte and platelet function.

Inducible nitric oxide synthase (iNOS) expression in liver and splenic T lymphocyte rise are associated with liver histological damage during experimental hepatitis A virus (HAV) infection in Callithrix jacchus.

Callithrix jacchus is considered a reliable animal model for hepatitis A virus (HAV) infection. All three HAV orally inoculated marmosets developed hepatitis - the infection was monitored by continuous virus shedding, high levels of serum enzyme alanine aminotransferase, specific antibody and seroconversion 3-6 weeks after HAV inoculation. HAV antigen was detected in liver by immunofluorescence 4 days post inoculation (PI) and onwards. To gain insight into the biological role of inducible nitric oxide synthase (iNOS) during immune-related acute liver injury the enzyme was searched in frozen biopsies: immunofluorescent labeling was found in the cytoplasm of liver cells mainly Kupffer's cells and spleen macrophages (CD68+) starting 11 days PI with maximum intensity on the fifth to sixth week PI. Necroinflammatory liver lesions characteristic of viral hepatitis were also observed at 10 days PI with maximum severity at 4 to 6 weeks PI. Furthermore, T lymphocytes (CD2+) were raised at this time point. No difference was evident in the frequency of B lymphocytes (CD20+). Therefore, iNOS expression preceded necroinflammatory liver lesion and maximal immunofluorescence reaction was coincident with tissue injury, supporting the hypothesis that NO contributes to hepatic cytotoxic mechanism but also to virus clearance. The concomitant rise in T-lymphocyte population may suggest a role for these cells in this and/or other independent HAV-induced pathological changes.

Silagem de sorgo de porte médio com diferentes teores de tanino e suculência no colmo. I. Nitrogênio amoniacal, pH e perdas de matéria seca / Intermediate sorghum silage with different tannin concentrations and steam moisture content. I. Ammonia nitrogen, pH and dry matter losses

Estudou-se o padräo de fermentaçäo de quatro híbridos de sorgo de porte médio com diferentes teores de tanino e suculência no colmo sob a forma de forragem verde e silagem. Os híbridos foram designados como: H1-híbrido de colmo suculento, sem tanino, H2-de colmo seco, sem tanino, H3-de colmo suculento, com tanino e H4-de colmo seco, com tanino, classificados em seis períodos de ensilagem, P1-material original-forragem näo ensilada, P2-silagem aberta após 24 horas, P3-silagem aberta aos sete dias, P4-aberta aos 14 dias, P5-aberta aos 28 dias e P6-aberta aos 56 dias de fermentaçäo. Os sorgos foram colhidos e ensilados com 104 dias de idade com gräos no estádio farináceo. O delineamento experimental foi inteiramente ao acaso, em esquema fatorial 4 x 6, utilizando-se o teste SNK para comparaçäo entre médias dos híbridos e períodos. O teor de MS à ensilagem foi de 27,6 por cento para os quatro híbridos. Devido às baixas perdas de MS (5,52 por cento -2,8 por cento) no P6, quase todos os híbridos apresentaram teores de MS iguais ao do material original, exceto o H2 que apresentou valor superior (30,27 por cento). A fraçäo de PB permaneceu estável em todos os tratamentos e apresentou valor médio de 8,96 por cento da MS. Os teores de N-NH3/NT nas silagens estiveram em torno de 0,65 a 0,90 por cento no P2 e de 1,27 a 2,53 por cento no P6, sendo H3 e H4 os de menor porcentagem. No P3, o pH da silagem já estava estabilizado e no P6, o índice médio foi de 3,72. Todas as silagens foram classificadas como de muito boa qualidade