Prediction of social structure and genetic relatedness in colonies of the facultative polygynous stingless bee Melipona bicolor (Hymenoptera, Apidae)

Stingless bee colonies typically consist of one single-mated mother queen and her worker offspring. The stingless bee Melipona bicolor (Hymenoptera: Apidae) shows facultative polygyny, which makes this species particularly suitable for testing theoretical expectations concerning social behavior. In this study, we investigated the social structure and genetic relatedness among workers from eight natural and six manipulated colonies of M. bicolor over a period of one year. The populations of M. bicolor contained monogynous and polygynous colonies. The estimated genetic relatedness among workers from monogynous and polygynous colonies was 0.75 ± 0.12 and 0.53 ± 0.16 (mean ± SEM), respectively. Although the parental genotypes had significant effects on genetic relatedness in monogynous and polygynous colonies, polygyny markedly decreased the relatedness among nestmate workers. Our findings also demonstrate that polygyny in M. bicolor may arise from the adoption of related or unrelated queens

A low-protein diet during pregnancy alters glucose metabolism and insulin secretion

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)In pancreatic islets, glucose metabolism is a key process for insulin secretion, and pregnancy requires an increase in insulin secretion to compensate for the typical insulin resistance at the end of this period. Because a low-protein diet decreases insulin secretion, this type of diet could impair glucose homeostasis, leading to gestational diabetes. In pancreatic islets, we investigated GLUT2, glucokinase and hexokinase expression patterns as well as glucose uptake, utilization and oxidation rates. Adult control non-pregnant (CNP) and control pregnant (CP) rats were fed a normal protein diet (17%), whereas low-protein non-pregnant (LPNP) and low-protein pregnant (LPP) rats were fed a low-protein diet (6%) from days 1 to 15 of pregnancy. The insulin secretion in 2.8?mmol l-1 of glucose was higher in islets from LPP rats than that in islets from CP, CNP and LPNP rats. Maximal insulin release was obtained at 8.3 and 16.7?mmol l-1 of glucose in LPP and CP groups, respectively. The glucose doseresponse curve from LPNP group was shifted to the right in relation to the CNP group. In the CP group, the concentrationresponse curve to glucose was shifted to the left compared with the CNP group. The LPP groups exhibited an inverted U-shape doseresponse curve. The alterations in the GLUT2, glucokinase and hexokinase expression patterns neither impaired glucose metabolism nor correlated with glucose islet sensitivity, suggesting that beta-cell sensitivity to glucose requires secondary events other than the observed metabolic/molecular events. Copyright (c) 2011 John Wiley & Sons, Ltd.302114121Fundacao de Amparo a Pesquisa do Estado de Mato Grosso [0786/2006]Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundacao de Amparo a Pesquisa do Estado de Mato Grosso [0786/2006]CNPq [305155/2004-0

Protein restriction in early life is associated with changes in insulin sensitivity and pancreatic beta-cell function during pregnancy

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Malnutrition in early life impairs glucose-stimulated insulin secretion in adulthood. Conversely, pregnancy is associated with a significant increase in glucose-stimulated insulin secretion under conditions of normoglycaemia. A failure in beta-cell adaptive changes may contribute to the onset of diabetes. Thus, glucose homeostasis and beta-cell function were evaluated in control-fed pregnant (CP) and non-pregnant (CNP) or protein-restricted pregnant (LPP) and non-pregnant (LPNP) rats, from fetal to adult life, and in protein-restricted rats that were recovered after weaning (RP and RNP). The typical insulin resistance of pregnancy was not observed in the RP rats, nor did pregnancy increase the insulin content/islet in the LPP group. The glucose dose-response curves from pregnant rats were shifted to the left in relation to the nonpregnant rats, except in the recovered group. Glucose utilisation but not oxidation in islets from the RP and LPP groups was reduced at a concentration of 8.3mM-glucose compared with islets from the CP group. Cyclic AMP content and the potentiation of glucose-stimulated insulin secretion by isobutylmethylxanthine at a concentration of 2.8mM-glucose indicated increased adenylyl cyclase 3 activity but reduced protein kinase A-alpha activity in islets from the RP and LPP rats. Protein kinase C (PKC)-alpha but not phospholipase C (PLC)-beta 1 expression was reduced in islets from the RP group. Phorbol-12-myristate 13-acetate produced a less potent stimulation of glucose-stimulated insulin secretion in the RP group. Thus, the alterations exhibited by islets from the LPP group appeared to be due to reduced islet mass and/or insulin biosynthesis. In the RP group the loss of the adaptive capacity apparently resulted from uncoupling between glucose metabolism and the amplifying signals of the secretory process, as well as a severe attenuation of the PLC/PKC pathway.o TEXTO COMPLETO DESTE ARTIGO, ESTARÁ DISPONÍVEL À PARTIR DE AGOSTO DE 2015.1092236247Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)FAPEMAT (Fundacao de Amparo a Pesquisa do Estado de Mato Grosso) [0786/2006]Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)CNPq [305155/2004-0]FAPEMAT (Fundacao de Amparo a Pesquisa do Estado de Mato Grosso) [0786/2006]CAPES [PROCAD 022/2007

Low-protein diets reduce PKA alpha expression in islets from pregnant rats

We investigated the effect of protein restriction on insulin secretion and the expression of protein kinase (PK)A alpha and PKC alpha in islets from control and pregnant rats. Adult control nonpregnant (CN) and control pregnant (CP) rats were fed a normal-protein diet (17%), whereas low-protein nonpregnant (LPN) and low-protein pregnant (LPP) rats were fed a low-protein diet (6%) for 15 d. In the presence of 2.8 and 8.3 mmol glucose/L, insulin secretion by islets of CP rats was higher than that by islets of CN rats. Compared with the CN groups, insulin secretion by islets of LPN rats was lower with 8.3 but not with 2.8 mmol glucose/L. The insulin secretion by islets of LPP rats was higher than by LPN rats at both glucose concentrations. IBMX (1 mmol/L), a phosphodiesterase inhibitor, increased insulin secretion by islets from pregnant rats, and this effect was greater in islets of CP rats than in LPP rats. Forskolin (0.01 -100 mu mol/L), a stimulator of adenylyl cyclase, increased insulin sacretion only in islets of CN and CP rats, with a higher 50% effective concentration in islets of CP rats compared with CN rats. The insulin secretion induced by phorbol 12-myristate 13-acetate (a stimulator of PKC) was higher in islets of LPN and LPP rats than in the respective controls, especially, at 8.3 mmol glucose/L. PKA alpha, but not PKC alpha, expression was lower in islets of rats fed low protein than in the controls, regardless of the physiological status of the rats. All endocrine cells of the islets, including beta-cells, expressed the PKA alpha isoform. The cytoplasmic distribution of this enzyme in beta-cells was not modified by pregnancy and/or protein restriction. In conclusion, our results indicate that the response of islets from rats fed low protein during pregnancy is similar to that of control rats, at least for physiologic glucose concentration. However, the decreased response to IBMX and forskolin indicates decreased production and/or sensitivity to cAMP; this was associated with a decrease in PKA expression, which may result in lower PKA activity.13581873187

Carboxymethylation of ulvan and chitosan and their use as polymeric components of bone cements

Ulvan, extracted from the green algae Ulva lactuca, and chitosan, extracted from Loligo forbesis squid-pen, were carboxymethylated, yielding polysaccharides with an average degree of substitution of ∼98% (carboxymethyl ulvan, CMU) and ∼87% (carboxymethyl chitosan, N,O-CMC). The carboxymethylation was confirmed by Fourier transform infrared spectroscopy and quantified by conductimetric titration and 1H nuclear magnetic resonance. The average molecular weight increased with the carboxymethylation (chitosan, Mn 145→296 kDa and Mw 227→416 kDa; ulvan, Mn 139→261 kDa and Mw 368→640 kDa), indicating successful chemical modifications. Mixtures of the modified polysaccharides were tested in the formulation of polyacrylic acid-free glass-ionomer bone cements. Mechanical and in vitro bioactivity tests indicate that the inclusion of CMU in the cement formulation, i.e. 0.50:0.50 N,O-CMC:CMU, enhances its mechanical performance (compressive strength 52.4 ± 8.0 MPa and modulus 2.3 ± 0.3 GPa), generates non-cytotoxic cements and induces the diffusion of Ca and/or P-based moieties from the surface to the bulk of the cements.The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under Grant Agreement No. REGPOT-CT2012-31633-POLARIS. Thanks are also due to Fundacao para a Ciencia e a Tecnologia (FCT, Portugal), European Union, QREN, FEDER and COMPETE for funding the QOPNA research unit (project PEst-C/QUI/UI0062/2011). R.A.P. and C.N. acknowledge their FCT post-doc Grants SFRH/BPD/39333/2007 and SFRH/BPD/46584/2008, respectively

O uso de contratos de gestão e incentivos profissionais no setor público de saúde The use of management contracts and professional incentives in the public health sector

A gestão por resultados constitui um dos pilares da reforma na gestão pública, inclusive na área da saúde, tendo como principais inovações: a institucionalização de contratos de gestão e a utilização de incentivos profissionais. O objetivo deste artigo de revisão de literatura é apresentar e discutir a utilidade e aplicabilidade de contratos de gestão e incentivos profissionais na gestão por resultados no setor público de saúde. A gestão por resultados só será possível quando existir corresponsabilidade e compromisso mútuo entre os trabalhadores e o nível diretivo. Por isso, as metas preestabelecidas devem ser pactuadas entre todos os atores envolvidos e avaliadas de forma periódica para que os incentivos profissionais sejam garantidos. Para efetivamente aumentar a responsabilização sobre os resultados desejados é preciso aprimorar os mecanismos de controle e monitoramento, definir de forma mais precisa indicadores e seus padrões no campo da assistência e da gestão, capacitar as partes envolvidas na elaboração do plano e aperfeiçoar o uso de incentivos profissionais.<br>Results-based management is a cornerstone of reform in public administration, including the health field, and has become the basis for other innovations such as the institutionalization of management contracts and the use of professional incentives. This review article aims to introduce and discuss the use of such management contracts in the public health sector. Management by results has developed means and tools that highlight the importance of shared responsibility and mutual commitment between workers and management-level directors. Thus, preset goals are negotiated among all the stakeholders and are evaluated periodically in order to grant professional incentives. It is necessary to improve the mechanisms for control and observation, to more precisely determine the healthcare and management indicators and their patterns, to train stakeholders in designing the plan, and to improve the use of professional incentives in order to effectively increase accountability vis-à-vis the desired results