Differential activity of GSK-3 isoforms regulates NF-kappa B and TRAIL- or TNF alpha induced apoptosis in pancreatic cancer cells

While TRAIL is a promising anticancer agent due to its ability to selectively induce apoptosis in neoplastic cells, many tumors, including pancreatic ductal adenocarcinoma (PDA), display intrinsic resistance, highlighting the need for TRAIL-sensitizing agents. Here we report that TRAIL-induced apoptosis in PDA cell lines is enhanced by pharmacological inhibition of glycogen synthase kinase-3 (GSK-3) or by shRNA-mediated depletion of either GSK-3 alpha or GSK-3 beta. In contrast, depletion of GSK-3 beta, but not GSK-3 alpha, sensitized PDA cell lines to TNF alpha-induced cell death. Further experiments demonstrated that TNF alpha-stimulated I kappa B alpha phosphorylation and degradation as well as p65 nuclear translocation were normal in GSK-3 beta-deficient MEFs. Nonetheless, inhibition of GSK-3 beta function in MEFs or PDA cell lines impaired the expression of the NF-kappa B target genes Bcl-xL and cIAP2, but not I kappa B alpha. Significantly, the expression of Bcl-xL and cIAP2 could be reestablished by expression of GSK-3 beta targeted to the nucleus but not GSK-3 beta targeted to the cytoplasm, suggesting that GSK-3 beta regulates NF-kappa B function within the nucleus. Consistent with this notion, chromatin immunoprecipitation demonstrated that GSK-3 inhibition resulted in either decreased p65 binding to the promoter of BIR3, which encodes cIAP2, or increased p50 binding as well as recruitment of SIRT1 and HDAC3 to the promoter of BCL2L1, which encodes Bcl-xL. Importantly, depletion of Bcl-xL but not cIAP2, mimicked the sensitizing effect of GSK-3 inhibition on TRAIL-induced apoptosis, whereas Bcl-xL overexpression ameliorated the sensitization by GSK-3 inhibition. These results not only suggest that GSK-3 beta overexpression and nuclear localization contribute to TNF alpha and TRAIL resistance via anti-apoptotic NF-kappa B genes such as Bcl-xL, but also provide a rationale for further exploration of GSK-3 inhibitors combined with TRAIL for the treatment of PDA.

Effects of process on microstructure and properties of translucent Dy-alpha-SiAlON sintered at lower temperatures

Hot pressing (HP) at higher sintering temperature has been a traditional and prevalent technique for the fabrication of alpha-SiAlON. In order to prepare translucent SiAlON more easily, LiF was used as a non-oxide sintering additive to lower the sintering temperature to <= 1650 degrees C. As a result, all of the samples possessed a good hardness and fracture toughness. At the same time, the lower temperature sintered samples showed a higher optical transmittance in the range of 2.5-5.5 mu m wavelength (0.5 mm in thickness). The maximum infrared transmission reached 68% at a wavelength of 3.3 mu m. The present work shows that the sintering process has a strong effect on microstructure and property of alpha-SiAlON. To be exact, a lower sintering temperature and longer holding time can produce some fully-developed microstrcture, which is beneficial for the optical transmittance. (C) 2008 The Ceramic Society of Japan. All rights reserved.

Efeitos pleiotrópicos da telmisartana nos tecidos adiposos branco e marrom: aumento da expressão gênica e proteica pan-PPAR em camundongos obesos

Receptores ativadores de proliferação perixossomal(PPARs) são fatores de transcrição envolvidos com a oxidação dos ácidos graxos e proliferação celular, mediando diversas vias, o que representa uma estratégia promissora para enfrentar as características da síndrome metabólica. Existem três isoformas de PPARs(PPARalfa, beta/delta e gama), que são diferencialmente expressos em diferentes tecidos.No presente estudo, objetivou-se avaliar os efeitos pleiotrópicos da telmisartana, um anti-hipertensivo, bloqueador do receptor AT1 da angiotensina e agonista parcial PPAR gama, no tecido adiposo branco (TAB) e marrom (TAM) em camundongos obesos induzido por dieta.Camundongos machos, da linhagem C57BL/6 foram alimentados com uma dieta padrão (standard-chow, 10% da energia proveniente de lipídios) ou com uma dieta com alto teor lipídico (high fat, 49% de energia proveniente de lipídios) durante 10 semanas. Em seguida, os animais foram distribuídos aleatoriamente em quatro grupos: SC, SC-T, HF e HF-T (n=10). O fármaco foi administrado (10mg/kg de dieta) durante 4 semanas para os grupos SC-T e HF-T.O grupo HF apresentou sobrepeso, hipertensão arterial sistêmica, perfil de adipocinas pró-inflamatórias, resistência insulínica, diminuição do gasto energético, comprometimento do metabolismo da glicose e distribuição anormal da massa adiposa. Além disso, a obesidade ocasionou diminuição da expressão de PPARalfa, beta/delta e gama noTAB e TAM, resultando na inadequação da captação de glicose e termogênese insuficiente. Por outro lado,a ativação das três isoformas de PPARs, a melhora do perfil inflamatório das adipocinas, o aumento da sensibilidade à insulina e a melhora da captação de glicose, foi vistaapós o tratamento com telmisartana. A ativação dos PPARs no TAB trouxe muitos benefícios. No TAM, resultados surpreendentes foram que a telmisartana provocou o aumento da expressão do recepetor adrenérgico beta 3 (RAβ3), induzido pela ativação de PPARbeta/delta e maior termogênese comaumento da expressão da proteína desacopladora1 (UCP1). Em conclusão, nossos resultados mostram que telmisartanaaumenta a expressão gênica e proteica PAN-PPAR no TAB e TAM em camundongos obesos induzidos por dieta. Nossas observações mostram que, apesar do grupo HF-T ter reduzido a ingestão energética, os efeitossão explicados pela ativação PAN-PPAR da telmisartana, causando a ativação da termogênese e resultando num balanço energético negativo.

Avaliação das alterações macro-hemodinâmicas, microcirculatórias, gasométricas, metabólicas e inflamatórias secundárias à sedação com dexmedetomidina em um modelo experimental de endotoxemia em hamsters

Pela sua alta incidência, morbidade, mortalidade e custos ao sistema de saúde, a sepse se destaca entre as diversas indicações de internação em unidade de terapia intensiva (UTI). A disfunção da microcirculação tem papel central na gênese e manutenção da síndrome séptica, sendo um marco fisiopatológico desta síndrome. Pacientes críticos invariavelmente estão ansiosos, agitados, confusos, desconfortáveis e/ou com dor. Neste contexto, drogas sedativas são amplamente utilizadas na medicina intensiva. A dexmedetomidina, um agonista potente e altamente seletivo dos receptores alfa-2 adrenérgicos, vem conquistando espaço como o sedativo de escolha nas UTIs por seus efeitos de sedação consciente, redução da duração e incidência de delirium e preservação da ventilação espontânea. Apesar destas possíveis vantagens, a indicação de uso da dexmedetomidina na síndrome séptica ainda carece de conhecimentos sobre seus efeitos na microcirculação e perfusão orgânica. Com o intuito de caracterizar os efeitos microcirculatórios da dexmedetomidina em um modelo murino de endotoxemia que permite estudos in vivo da inflamação e disfunção da perfusão microvascular, hamsters Sírios dourados submetidos à endotoxemia induzida por administração intravenosa de lipopolissacarídeo de Escherichia coli (LPS, 1,0 mg.kg-1) foram sedados com dexmedetomidina (5,0 μg.kg.h-1). A microscopia intravital da preparação experimental (câmara dorsal) permitiu a realização de uma análise quantitativa das variáveis microvasculares e do rolamento e adesão de leucócitos à parede venular. Também foram analisados os parâmetros macro-hemodinâmicos e gasométricos (arterial e venoso portal), as concentrações de lactato arterial e venoso portal, a água pulmonar total e a sobrevivência do animal. Animais não-endotoxêmicos e/ou tratados com solução salina a 0,9% serviram como controles neste experimento. O LPS aumentou o rolamento e a adesão de leucócitos à parede venular, diminuiu a densidade capilar funcional e a velocidade das hemácias nos capilares e induziu acidose metabólica. O tratamento com dexmedetomidina atenuou significativamente estas respostas patológicas (p < 0,05). A frequência de pulso dos animais foi significativamente reduzida pela droga (p < 0,05). Outros resultados não foram tão expressivos (estatisticamente ou clinicamente). Estes resultados indicam que a utilização de dexmedetomidina produz um efeito protetor sobre a microcirculação da câmara dorsal de hamsters endotoxêmicos. Efeitos anti-inflamatórios da dexmedetomidina sobre os leucócitos e o endotélio poderiam melhorar a perfusão capilar e representar o mecanismo in vivo de ação da droga na microcirculação.

Use of dopamine antagonists on induced spawning of Indian major carps

To test the efficacy of the technique of using dopamine-antagonists with pituitary extracts, experiments were conducted in July/August '93, at the CIFE Fresh water Fish Farm, Powerkheda. In all, 35 sets (1 female x 2 male in each set) were tried individually. 19 sets were treated with Domperidone (DOM) and Carp Pituitary Extract (CPE) and they constituted the experimental sets, while the rest 16 were treated with CPE and formed the control sets. The breeding, complete ovulation and hatching was 84.2%, 87.5% and 85.7%, respectively in the experimental sets whereas it was 93.7%, 60% and 72.7%, respectively in case of control sets. Experimental sets yielded 1.20 lakh spawn/kg body wt. (female) as compared to 0.83 lakh spawn kg body wt. (female) received from control sets on average basis. When DOM was used at 50-60% there was 100% breeding success but when increased to 70%, breeding rate fell to 66%. In mass breeding of Catla in the circular hatchery DOM mixed with CPE in 50:50 ratio gave excellent results.

Adaptive evolution of primate TRIM5 alpha, a gene restricting HIV-1 infection

Recent studies showed that nonhuman primate TRIM5 alpha can efficiently block HIV-1 infection in human cell lines. It can also restrict other retroviruses, therefore, suggested as a general defender against retrovirus infection. Here, we present an evolutionary analysis of TRIM5 alpha in primates. Our results demonstrated that TRIM5a has been evolving rapidly in primates, which is likely caused by Darwinian positive selection. The SPRY domain of TRM5 alpha, which may be responsible for recognition of incoming viral capsids showed higher nonsynonymous/synonymous substitution ratios than the non-SPRY domain, indicating that the adaptive evolution of TRIM5a ill primates might be an innate strategy developed in defending retrovirus infection during primate evolution. In addition, the comparative protein sequence analysis suggested that the amino acid substitution pattern at a single site (344R/Q/P) located in the SPRY domain may explain the differences in Susceptibilities of HIV-1 infection in diverse primate species. (c) 2005 Elsevier B.V. All rights reserved.

Cloning and purification of alpha-neurotoxins from king cobra (Ophiophagus hannah)

Thirteen complete and three partial cDNA sequences were cloned from the constructed king cobra (Ophiophagus hannah) venom gland cDNA library. Phylogenetic analysis of nucleotide sequences of king cobra with those from other snake venoms revealed that obta

Cloning of bradykinin precursor cDNAs from skin of Bombina maxima reveals novel bombinakinin M antagonists and a bradykinin potential peptide

Bombinakinin M (DLPKINRKGP-bradykinin) is a bradykinin-related peptide purified from skin secretions of the frog Bombina maxima. As previously reported, its biosynthesis is characterized by a tandem repeats with various copy numbers of the peptide and sometimes co-expressed with other structure-function distinguishable peptides. At present study, two novel cDNAs encoding bombinakinin M and its variants were cloned from a cDNA library from the skin of the frog. The encoded two precursor proteins are common in that each contains three repeats of a novel 16-amino acid peptide unit and one copy of kinestatin at their N- and C-terminal parts, respectively. They differ in that the first precursor contains two copies of bombinakinin M and the second one contains one copy of a novel bombinakinin M variant. Bombinakinin M was found to elicit concentration-dependent contractile effects on guinea pig ileum, with an EC50 value of 4 nM that is four times higher than that of bradykinin (1 nM). Interestingly, the synthetic peptide (DYTIRTRLH-amide), as deduced from the 16-amino acid peptide repeats in the newly cloned cDNAs, possessed weak inhibitory activity on the contractile effects of bombinakinin M, but not on that of bradykinin. Furthermore, the newly identified bombinakinin M variant (DLSKMSFLHG-Ile(1)-bradykinin), did not show contractile activity on guinea pig ileum, but showed potentiation effect on the myotropic activity of bradykinin. In a molar raito of 1:58, it augmented the activity of bradykinin up to two-fold. (C) 2004 Elsevier B.V. All rights reserved.

Enhanced poisson sum representation for alpha-stable processes

In this paper we present Poisson sum series representations for α-stable (αS) random variables and a-stable processes, in particular concentrating on continuous-time autoregressive (CAR) models driven by α-stable Lévy processes. Our representations aim to provide a conditionally Gaussian framework, which will allow parameter estimation using Rao-Blackwellised versions of state of the art Bayesian computational methods such as particle filters and Markov chain Monte Carlo (MCMC). To overcome the issues due to truncation of the series, novel residual approximations are developed. Simulations demonstrate the potential of these Poisson sum representations for inference in otherwise intractable α-stable models. © 2011 IEEE.

The free alpha amino acid nitrogen contents of some common food fishes of Kakinada region, Andhra Pradesh

The moisture and free alpha amino nitrogen contents of some important food fishes and shell fishes of Kakinada region have been studied. Crustaceans and molluscs contain free alpha amino acids in quantities several times higher than all other aquatic animals examined in this study. Their probable role in the physiological activities of these animals has been discussed.

Polymorphisms of the estrogen receptor alpha (ESR1) gene and the risk of Alzheimer's disease in a southern Chinese community

Background: Alzheimer's disease (AD) is a neurodegenerative disease with a higher prevalence in women. Expression of estrogen receptor 1 (ESR1) gene has been identified throughout the brain. Owing to the putative neuroprotective effects of estrogen, estro