The interaction between heparin and Lys49 phospholipase A(2) reveals the natural binding of heparin on the enzyme

We have studied at a molecular level the interaction of heparins on bothropstoxin-1 (BthTx-1), a phospholipase A(2) toxin. The protein was monitored using gel filtration chromatography, dynamic light scattering (DLS), circular dichroism (CD), attenuated total reflectance Fourier transform infrared (ATR-FTIR) and intrinsic tryptophan fluorescence emission (ITFE) spectroscopy. The elution profile of the protein presents a displacement of the protein peak to larger complexes when interacting with higher concentration of heparin. The DLS results shows two R-h at a molar ratio of 1, one to the distribution of the protein and the second for the action of heparin on BthTx-I structures, and a large distribution with the increase of protein. The interaction is accompanied by significant changes in the CD spectra, showing two common features: a decrease in signal at 208 nm (3 and 6 kDa heparins) and an isodichroic point near 226 nm (3 kDa heparin). FTIR spectra indicate that only a few amino acid residues are involved in this interaction. Alterations in the ITFE by binding heparins suggest that the initial binding occurs on the ventral face of BthTx-1. Together, these results add an experimental and structural basis on the action mechanism of the heparins over the phospholipases A(2) and provide a molecular model to elucidate the interaction of the enzyme-heparin complex at a molecular level. (c) 2005 Elsevier B.V. All rights reserved.

Pharmacokinetic Profile of Liposome-Encapsulated Ropivacaine after Maxillary Infiltration Anaesthesia

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Purification and renal effects of phospholipase A(2) isolated from Bothrops insularis venom

Bothrops insularis venom contains a variety of substances presumably responsible for several pharmacological effects. We investigated the biochemical and biological effects of phospholipase A(2) protein isolated from B. insularis venom and the chromatographic profile showed 7 main fractions and the main phospholipase A(2) (PLA(2)) enzymatic activity was detected in fractions IV and V. Fraction IV was submitted to a new chromatographic procedure on ion exchange chromatography, which allowed the elution of 5 main fractions designated as lV-1 to IV-5, from which lV-4 constituted the main fraction. The molecular homogeneity of this fraction was characterized by high-performance liquid chromatography (HPLC) and demonstrated by mass spectrometry (MS), which showed a molecular mass of 13984.20 Da; its N-terminal sequence presented a high amino acid identity (up to 95%) with the PLA(2) of Bothrops jararaca and Bothrops asper. Phospholipase A(2) isolated from B. insularis (Bi PLA(2)) venom (10 mu g/mL) was also studied as to its effect on the renal function of isolated perfused kidneys of Wistar rats (n = 6). Bi PLA(2) increased perfusion pressure (PP), renal vascular resistance (RVR), urinary flow (UF) and glomerular filtration rate (GFR). Sodium (%TNa+) and chloride tubular reabsorption (%TCl-) decreased at 120 min, without alteration in potassium transport. In conclusion, PLA(2) isolated from B. insularis venom promoted renal alterations in the isolated perfused rat kidney. (c) 2007 Elsevier Ltd. All rights reserved.

Profile of cortisol, glycaemia, and blood parameters of American Bullfrog tadpoles Lithobates catesbeianus exposed to density and hypoxia stressors

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Growth, fat content and fatty acid profile of South American catfish, surubim (Pseudoplatystoma fasciatum) juveniles fed live, commercial and formulated diets

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Isolation of extraintestinal pathogenic Escherichia coli from diarrheic dogs and their antimicrobial resistance profile

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ingredient classification according to the digestible amino acid profile: an exploratory analysis

This study aimed: 1) to classify ingredients according to the digestible amino acid (AA) profile; 2) to determine ingredients with AA profile closer to the ideal for broiler chickens; and 3) to compare digestible AA profiles from simulated diets with the ideal protein profile. The digestible AA levels of 30 ingredients were compiled from the literature and presented as percentages of lysine according to the ideal protein concept. Cluster and principal component analyses (exploratory analyses) were used to compose and describe groups of ingredients according to AA profiles. Four ingredient groups were identified by cluster analysis, and the classification of the ingredients within each of these groups was obtained from a principal component analysis, showing 11 classes of ingredients with similar digestible AA profiles. The ingredients with AA profiles closer to the ideal protein were meat and bone meal 45, fish meal 60 and wheat germ meal, all of them constituting Class 1; the ingredients from the other classes gradually diverged from the ideal protein. Soybean meal, which is the main protein source for poultry, showed good AA balance since it was included in Class 3. on the contrary, corn, which is the main energy source in poultry diets, was classified in Class 8. Dietary AA profiles were improved when corn and/or soybean meal were partially or totally replaced in the simulations by ingredients with better AA balance.

Evaluation of electrophoretic profile and albumin quota in the cerebrospinal fluid of dogs with distemper showing or not neurvous signs

Estudaram-se o perfil eletroforético das proteínas liquóricas e a cota de albumina em cães sem e com cinomose na fase neurológica e não-neurológica. A punção da cisterna magna para a obtenção de amostras de liquor realizou-se em 30 cães. Analisaram-se teores de proteínas totais, cota de albumina e fracionamento eletroforético das proteínas liquóricas em gel de agarose. Os resultados foram semelhantes nos cães normais e nos cães com cinomose sem sinais neurológicos e significativamente elevados no grupo de cães com cinomose apresentando sinais neurológicos. O estudo do quadro protéico do líquido cérebroespinhal foi útil e contribuiu significativamente na detecção de lesões ao sistema nervoso central e de danos à barreira hematoencefálica durante a fase neurológica da cinomose.

Hematological profile of healthy Pantaneiro horses

Determinaram-se os valores do hemograma de 187 eqüinos sadios da raça Pantaneira. Para a composição de seis grupos experimentais consideraram-se a faixa etária e o sexo. Verificaram-se 6,2± 1,2 a 8,9± 2,3 hemácias/µl (x10(6)), 32,0± 4,0 a 37,0± 2,8% de volume globular (VG), 11,5± 1,0 a 12,8± 1,6g de teor de hemoglobina/dl, 11,0± 3,2 a 17,0± 2,8 leucócitos/µl (x 10³), 4,9± 1,8 a 7,5± 1,5 neutrófilos segmentados/µl (x 10³) e 5,2± 2,0 a 8,6± 2,0 linfócitos/µl (x 10³). Observaram-se valores mais baixos na contagem de hemácias, e VG e valores mais altos do volume globular médio (VGM) em cavalos castrados (acima de 25 meses de idade). As contagens de leucócitos e neutrófilos segmentados em potros com até oito meses de idade apresentaram valores mais elevados que os encontrados em animais acima dos 25 meses de idade. Constatou-se que não houve influência do sexo nos parâmetros analisados.

Organic and inorganic sources of zinc, copper and selenium in diets for dairy cows: intake, blood metabolic profile, milk yield and composition

The present study was carried out with the objective of evaluating the effects of feeding dairy cows with organic or inorganic sources of zinc (Zn), copper (Cu) and selenium (Se) on blood concentrations of these minerals, blood metabolic profiles, nutrient intake and milk yield and composition. Nineteen Holstein cows were selected and randomly assigned to two groups for receiving organic (n = 9) or inorganic (n = 10) sources of Zn, Cu and Se from 60 days before the expected date of calving to 80 days of lactation. Samples of feed, orts and milk were collected for analysis. Body condition score (BCS) was determined and blood samples were collected for analysis of Zn, Cu and Se concentrations, as well as for metabolic profile. Supplying organic or inorganic sources of Zn, Cu, and Se did not affect dry matter and nutrient intake, blood metabolic profile, milk yield and composition, plasma concentration of these minerals, and BCS or change the BCS in cows from 60 days before the expected date of calving to 80 days of lactation. An effect of time was observed on all feed intake variables, plasma concentrations of Zn and Se, milk yield, milk protein content, BCS and change in BCS.

Performance and hormonal profile in broiler chickens fed with different energy levels during post restriction period

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Proteome of the phytopathogen Xanthomonas citri subsp citri: a global expression profile

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of different fat sources on the performance, egg quality, and lipid profile of egg yolks of commercial layers in the second laying cycle

This study was designed to evaluate the effects of different fat sources on the performance, egg quality, and lipid profile of the egg yolks of layers in their second production cycle. The fat sources were cottonseed oil, soybean oil, lard, sunflower oil, or canola oil. Experimental diets were fed to postmolt ISA Brown layers at 70 wk of age and the experimental period was 74 to 86 wk of age. The different fat sources did not influence performance or eggshell quality, but lipid profile of the egg yolk changed as a function of dietary fat sources. In general, the best changes, such as lower level of saturated fatty acids, higher levels of alpha-linolenic acid and DHA, and lower linoleic acid levels, were promoted by the addition of canola oil, but it did not promote enrichment of the eggs with polyunsaturated fatty acids.

Impacts of limestone and nitrogen top dressing application on the potassium content in the soil profile and marandu-grass leaf concentration

Objetivou-se avaliar os efeitos de nitrogênio (0, 100, 200, 300 e 400 kg/ha.ano), com ou sem aplicação de calcário dolomítico em cobertura, sobre o teor de potássio (K) do solo nas profundidades de 0 a 5; 5 a 10; e 10 a 20 cm e a concentração de potássio na planta. O experimento foi realizado em Latossolo Vermelho distroférrico de relevo suavemente ondulado, disposto em esquema fatorial 5 × 2, em blocos casualizados, com quatro repetições. A adubação nitrogenada promoveu aumento linear na concentração de potássio na planta e no teor desse mineral na camada de 0 a 5 cm do solo. Ocorreu efeito de inibição competitiva entre a absorção de potássio e cálcio e entre potássio e magnésio. Embora uma fração significativa de potássio retorne à camada superficial do solo pelo resíduo de forragem, em decorrência da maior produção de massa, o aumento da concentração de potássio na planta nas mais altas doses de nitrogênio comprova a importância do suprimento de potássio para a planta, por intensificar a massa de forragem.