Lasiodiplodan, an exocellular (1 -> 6)-beta-d-glucan from Lasiodiplodia theobromae MMPI: production on glucose, fermentation kinetics, rheology and anti-proliferative activity

Lasiodiplodan, an exopolysaccharide of the (1 -> 6)-beta-d-glucan type, is produced by Lasiodiplodia theobromae MMPI when grown under submerged culture on glucose. The objective of this study was to evaluate lasiodiplodan production by examining the effects of carbon (glucose, fructose, maltose, sucrose) and nitrogen sources (KNO3, (NH4)(2)SO4, urea, yeast extract, peptone), its production in shake flasks compared to a stirred-tank bioreactor, and to study the rheology of lasiodiplodan, and lasiodiplodan's anti-proliferative effect on breast cancer MCF-7 cells. Although glucose (2.05 +/- A 0.05 g L-1), maltose (2.08 +/- A 0.04 g L-1) and yeast extract (2.46 +/- A 0.06 g L-1) produced the highest amounts of lasiodiplodan, urea as N source resulted in more lasiodiplodan per unit biomass than yeast extract (0.74 +/- A 0.006 vs. 0.22 +/- A 0.008 g g(-1)). A comparison of the fermentative parameters of L. theobromae MMPI in shake flasks and a stirred-tank bioreactor at 120 h on glucose as carbon source showed maximum lasiodiplodan production in agitated flasks (7.01 +/- A 0.07 g L-1) with a specific yield of 0.25 +/- A 0.57 g g(-1) and a volumetric productivity of 0.06 +/- A 0.001 g L-1 h(-1). A factorial 2(2) statistical design developed to evaluate the effect of glucose concentration (20-60 g L-1) and impeller speed (100-200 rpm) on lasiodiplodan production in the bioreactor showed the highest production (6.32 g L-1) at 72 h. Lasiodiplodan presented pseudoplastic behaviour, and the apparent viscosity increased at 60A degrees C in the presence of CaCl2. Anti-proliferative activity of lasiodiplodan was demonstrated in MCF-7 cells, which was time- and dose-dependent with an IC50 of 100 mu g lasiodiplodan mL(-1).

Thermodynamics of Axial Substitution and Kinetics of Reactions with Amino Acids for the Paddlewheel Complex Tetrakis(acetato)chloridodiruthenium(II,III)

The known paddlewheel, tetrakis(acetato)chloridodiruthenium(II,III), offers a versatile synthetic route to a novel class of antitumor diruthenium(II,III) metallo drugs, where the equatorial ligands are nonsteroidal anti-inflammatory carboxylates. This complex was studied here as a soluble starting prototype model for antitumor analogues to elucidate the reactivity of the [Ru-2(CH3COO)(4)](+) framework. Thermodynamic studies on equilibration reactions for axial substitution of water by chloride and kinetic studies on reactions of the diaqua complexes with the amino acids glycine, cysteine, histidine, and tryptophan were performed. The standard thermodynamic reaction parameters Delta H degrees, Delta S degrees, and Delta V degrees were determined and showed that both of the sequential axial substitution reactions are enthalpy driven. Kinetic rate laws and rate constants were determined for the axial substitution reactions of coordinated water by the amino acids that gave the corresponding aqua(amino acid)-Ru-2 substituted species. The results revealed that the [Ru-2(CH3COO)(4)](+) paddlewheel framework remained stable during the axial ligand substitution reactions and was also mostly preserved in the presence of the amino acids.

Valor da PET/CT na abordagem do câncer de cabeça e pescoço

OBJETIVO: Avaliar a PET/CT na abordagem de pacientes com câncer de cabeça e pescoço. MATERIAIS E MÉTODOS: Estudo retrospectivo de 63 prontuários e exames de PET/CT de pacientes com câncer de cabeça e pescoço. RESULTADOS: Foram encontradas alterações em 76% dos exames. Destes, 7 (11%) foram considerados falso-positivos, com SUV < 5,0. A PET/CT mostrou-se negativa em 15 situações (24%). Dos 14 casos nos quais se utilizou o exame para estadiamento, em 3 (22%) houve aumento no estadiamento. CONCLUSÃO: A PET/CT mostra-se como exame de potencial valor na rotina de avaliação de pacientes com câncer de cabeça e pescoço, entretanto, necessitamos de maior número de casos para definirmos protocolo de uso.

Resolubilidade da estratégia saúde da família e unidades básicas de saúde tradicionais: contribuições do Pet-Saúde

O Programa de Educação pelo Trabalho para a Saúde (PET-Saúde) materializa uma política indutora de novas relações entre instituições de ensino de nível superior e a rede assistencial à saúde. A Universidade de São Paulo - Campus de Ribeirão Preto e a Secretaria de Saúde do município, selecionadas pelo PET-Saúde/2009, avaliaram a resolubilidade das Unidades Básicas de Saúde (UBS) e das Unidades de Estratégia Saúde da Família (ESF), como forma de contribuir para a qualificação da Atenção Básica. Foi realizado um estudo transversal em 13 Unidades de Saúde (oito ESF e cinco UBS), com a participação de 216 alunos dos cursos da área da saúde, 30 preceptores (profissionais) da rede pública de saúde e cinco tutores (docentes). Foram coletados dados de 12.494 atendimentos, sendo 7.129 (58,9%) em ESF e 4.963 (41,1%) em UBS, compostos por 4.059 (33,6%) pessoas do sexo masculino e 8.035 (66,4%) do feminino.As UBS referenciaram mais pacientes do que as Unidades de ESF (OR = 1,67; IC 95% 1,46 - 1,90; [p < 0,05]). As especialidades com maior demanda por encaminhamentos foram oftalmologia, cardiologia e ortopedia. A ESF apresenta-se como modelo assistencial com maior resolubilidade, e o PET-Saúde é uma iniciativa importante, considerando-se que estimula a ampliação desse modelo.

Plasma kinetics of an LDL-like nanoemulsion and lipid transfer to HDL in subjects with glucose intolerance

OBJECTIVE: Glucose intolerance is frequently associated with an altered plasma lipid profile and increased cardiovascular disease risk. Nonetheless, lipid metabolism is scarcely studied in normolipidemic glucose-intolerant patients. The aim of this study was to investigate whether important lipid metabolic parameters, such as the kinetics of LDL free and esterified cholesterol and the transfer of lipids to HDL, are altered in glucose-intolerant patients with normal plasma lipids. METHODS: Fourteen glucose-intolerant patients and 15 control patients were studied; none of the patients had cardiovascular disease manifestations, and they were paired for age, sex, race and co-morbidities. A nanoemulsion resembling a LDL lipid composition (LDE) labeled with 14C-cholesteryl ester and ³H-free cholesterol was intravenously injected, and blood samples were collected over a 24-h period to determine the fractional clearance rate of the labels by compartmental analysis. The transfer of free and esterified cholesterol, triglycerides and phospholipids from the LDE to HDL was measured by the incubation of the LDE with plasma and radioactivity counting of the supernatant after chemical precipitation of non-HDL fractions. RESULTS: The levels of LDL, non-HDL and HDL cholesterol, triglycerides, apo A1 and apo B were equal in both groups. The 14C-esterified cholesterol fractional clearance rate was not different between glucose-intolerant and control patients, but the ³H-free-cholesterol fractional clearance rate was greater in glucose-intolerant patients than in control patients. The lipid transfer to HDL was equal in both groups. CONCLUSION: In these glucose-intolerant patients with normal plasma lipids, a faster removal of LDE free cholesterol was the only lipid metabolic alteration detected in our study. This finding suggests that the dissociation of free cholesterol from lipoprotein particles occurs in normolipidemic glucose intolerance and may participate in atherogenic signaling.