993 resultados para Proteína de ligação de cálcio S100 – S100-like
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Toll-like receptor 4 (TLR4), the signal-transducing molecule of the LPS receptor complex, plays a fundamental role in the sensing of LPS from gram-negative bacteria. Activation of TLR4 signaling pathways by LPS is a critical upstream event in the pathogenesis of gram-negative sepsis, making TLR4 an attractive target for novel antisepsis therapy. To validate the concept of TLR4-targeted treatment strategies in gram-negative sepsis, we first showed that TLR4(-/-) and myeloid differentiation primary response gene 88 (MyD88)(-/-) mice were fully resistant to Escherichia coli-induced septic shock, whereas TLR2(-/-) and wild-type mice rapidly died of fulminant sepsis. Neutralizing anti-TLR4 antibodies were then generated using a soluble chimeric fusion protein composed of the N-terminal domain of mouse TLR4 (amino acids 1-334) and the Fc portion of human IgG1. Anti-TLR4 antibodies inhibited intracellular signaling, markedly reduced cytokine production, and protected mice from lethal endotoxic shock and E. coli sepsis when administered in a prophylactic and therapeutic manner up to 13 h after the onset of bacterial sepsis. These experimental data provide strong support for the concept of TLR4-targeted therapy for gram-negative sepsis.
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IGF2 is an autocrine ligand for the beta cell IGF1R receptor and GLP-1 increases the activity of this autocrine loop by enhancing IGF1R expression, a mechanism that mediates the trophic effects of GLP-1 on beta cell mass and function. Here, we investigated the regulation of IGF2 biosynthesis and secretion. We showed that glutamine rapidly and strongly induced IGF2 mRNA translation using reporter constructs transduced in MIN6 cells and primary islet cells. This was followed by rapid secretion of IGF2 via the regulated pathway, as revealed by the presence of mature IGF2 in insulin granule fractions and by inhibition of secretion by nimodipine and diazoxide. When maximally stimulated by glutamine, the amount of secreted IGF2 rapidly exceeded its initial intracellular pool and tolbutamide, and high K(+) increased IGF2 secretion only marginally. This indicates that the intracellular pool of IGF2 is small and that sustained secretion requires de novo synthesis. The stimulatory effect of glutamine necessitates its metabolism but not mTOR activation. Finally, exposure of insulinomas or beta cells to glutamine induced Akt phosphorylation, an effect that was dependent on IGF2 secretion, and reduced cytokine-induced apoptosis. Thus, glutamine controls the activity of the beta cell IGF2/IGF1R autocrine loop by increasing the biosynthesis and secretion of IGF2. This autocrine loop can thus integrate changes in feeding and metabolic state to adapt beta cell mass and function.
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Sucessivos Governos, Organizações Governamentais e responsáveis desses Governos e Organizações têm apresentado até ao presente e de forma veemente e repetida uma sistemática ligação da língua portuguesa não só à identidade nacional como também a uma forma de reconhecimento internacional ligada a uma visão mais ampla, geolinguística e geopolítica de uma Lusofonia, capaz de agir de forma concertada conforme ao exemplo de outros blocos político-linguísticos, como o Francófono, o Espanófono ou o Anglófono, por forma a promover o uso alargado da língua portuguesa como língua internacional e o desenvolvimento económico e social dos países membros da Comunidade de Países de Língua Portuguesa (CPLP). Este trabalho é um estudo sobre a indissociável relação entre as reiteradas afirmações constantes no discurso oficial e nos documentos legais que as suportam no que respeita à promoção e difusão do uso da Língua Portuguesa quer como Língua Estrangeira (PLE), quer na promoção do seu uso nas Organizações Internacionais de que Portugal, os Países de Língua Portuguesa ou de Língua Oficial Portuguesa fazem parte. Este discurso oficial sobre a língua e a documentação legal que a suporta, que surge sempre apresentado como uma prioridade política e como desígnio nacional, impõe a necessária confrontação entre a afirmação daqueles propósitos e a realidade da política de língua implementada de facto, ou seja, a forma como esse desígnio nacional é levado à prática pelo Estado e, logo, pelos governantes que agem em seu nome e definem esta política de língua externa ao longo de um período de cerca de 30 anos de democracia em que este estudo se centra.
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Human papillomavirus (HPV) vaccines based on L1 virus-like particle (VLP) can prevent genital HPV infection and associated lesions after three intramuscular injections. Needle-free administration might facilitate vaccine implementation, especially in developing countries. Here we have investigated rectal and vaginal administration of HPV16 L1 VLPs in mice and their ability to induce anti-VLP and HPV16-neutralizing antibodies in serum and in genital, rectal and oral secretions. Rectal and vaginal immunizations were not effective in the absence of adjuvant. Cholera toxin was able to enhance systemic and mucosal anti-VLPs responses after rectal immunization, but not after vaginal immunization. Rectal immunization with Resiquimod and to a lesser extent Imiquimod, but not monophosphoryl lipid A, induced anti-HPV16 VLP antibodies in serum and secretions. Vaginal immunization was immunogenic only if administered in mice treated with nonoxynol-9, a disrupter of the cervico-vaginal epithelium. Our findings show that rectal and vaginal administration of VLPs can induce significant HPV16-neutralizing antibody levels in secretions, despite the fact that low titers are induced in serum. Imidazoquinolines, largely used to treat genital and anal warts, and nonoxonol-9, used as genital microbicide/spermicide were identified as adjuvants that could be safely used by the rectal or vaginal route, respectively.
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A pesca teve sempre grande importância socioeconómica para as comunidades costeiras de Cabo Verde, oferecendo meios de subsistência e, devido à vocação marítima do povo Cabo-verdiano, possibilidades de emprego. O peixe aparece como componente importante na alimentação da população e, por ser fonte de proteína e um animal de baixo custo para a população, requer que a sua exploração seja feita em moldes sustentáveis, perpetuando no tempo a disponibilidade desse recurso para toda a sociedade. Este trabalho apresenta o estudo das perceções dos pescadores sobre a sustentabilidade da exploração dos recursos haliêuticos pesqueiros e a pesca artesanal dominante na ilha. A pesca é uma das principais atividades económicas da zona costeira da Ilha do Sal, além de ser uma importante atividade de subsistência para as três comunidades haliêuticas da ilha. Com o objetivo de discutir caminhos sustentáveis para a atividade, reflete-se sobre a sustentabilidade da pesca artesanal na comunidade da Palmeira, Ilha do Sal, Cabo Verde. Numa comunidade como a Palmeira, onde a pesca é tipicamente artesanal, encontramos diversos elementos que garantem a sustentabilidade da atividade. Conhecer e desenvolver novos mecanismos que visam educar e criar políticas sustentáveis para a atividade e gestão dos recursos é importante para a nova conjuntura em que se vive. A educação e a organização dos pescadores, bem como a descentralização e a gestão participativa dos recursos pesqueiros, são condições fundamentais para a sustentabilidade da pesca. Este trabalho tenta responder à escassez de estudos sobre as comunidades piscatórias em Cabo Verde de modo a favorecer o conhecimento ambiental que potenciará a criação de estratégias-chave para a sustentabilidade, a análise dos projetos criados até à data e a respetiva implementação, permitindo a identificação das causas do insucesso total ou parcial, bem como a identificação das causas para o fraco envolvimento da comunidade piscatória na implementação dos projetos. Fishery has always been of great social economic importance for the coastal communities of Cape Verde, offering means of subsistence and employment opportunities due to their maritime vocation. Fish is an important food component for the population. Since fishery is a source of low-cost animal protein, its exploration must be sustainable in order to be permanently available for the community. This paper presents a study on the perception of fishermen on the sustainable exploitation of fishery resources in a symbiosis with the dominant artesanal fishing practiced on the island. Fishing is one of the main economic activities of the coastal zone of Sal island, besides being an important subsistence activity for the three fishing communities of the island. Aiming to discuss ways for sustainable activity, we will reflect on the sustainability of the traditional fishing in the community of Palmeira, Sal Island, Cape Verde. In a community like Palmeira, where fishing is typically artesanal, we find many elements that ensure the sustainability of the activity, such as the predominant use of renewable natural resources and the diversity of species caught. in Sal Inland knowing and developing new mechanisms to educate, create sustainable policies for the activity and resource management are important to the environment. Education and organization of fishermen, as well as decentralization and participatory management of fishery resources, are fundamental to the sustainability of fisheries. This work tries to answer the scarcity of studies on fishing communities in order to promote environmental knowledge that will enhance the creation of key strategies for sustainability, the analysis of projects created to date and the respective implementation, allowing the identification of the causes of the total or partial failure, as well as the identification of the causes for the poor involvement of the fishing community in the implementation of projects.
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Purpose: Posterior microphthalmos (MCOP)/nanophthalmos (NNO) is a developmental anomaly characterized by extreme hyperopia due to short axial length. The population of the Faroe Islands shows a high prevalence of an autosomal recessive form (arMCOP). The gene mutated in arMCOP is not yet known.Methods: Genetic mapping by linkage analysis using microsatellite and single nucleotide polymorphisms, mutation analysis by PCR and sequencing, molecular modellingResults: Having refined the position of the disease locus (MCOP6) in an interval of 250 kb in chromosome 2q37.1 in Faroese families, we detected 3 mutations in a novel gene, LOC646960: Patients of 10 different Faroese families were either homozygous (n=22) for c.926G>C (p.Trp309Ser) or compound heterozygous (n=6) for c.926G>C and c.526C>G (p.Arg176Gly), whereas a homozygous 1 bp duplication (c.1066dupC) was identified in patients with arNNO from a Tunisian family. In two unrelated patients with MCOP, no LOC646960 mutation was found. LOC646960 is expressed in the human adult retina and RPE. The expression of the mouse homologue in the eye can be first detected at E17 and is highest in adults. The predicted protein is a 603 amino acid long secreted trypsin-like serine peptidase. c.1066dupC should result in a functional null allele. Molecular modelling of the p.Trp309Ser mutant suggests that both affinity and reactivity of the enzyme towards in vivo substrates are substantially reduced.Conclusions: Postnatal growth of the eye is important for proper development of the refractive components (emmetropization), and is mainly due to elongation of the posterior segment from 10-11 mm at birth to 15-16 mm at the age of 13 years. Optical defocus leads to changes in axial length by moving the retina towards the image plane. arMCOP may theoretically be explained, in line with the expression pattern of LOC646960, by a postnatal growth retardation of the posterior segment.
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Abstract: To have an added value over BMD, a CRF of osteoporotic fracture must be predictable of the fracture, independent of BMD, reversible and quantifiable. Many major recognized CRF exist.Out of these factorsmany of themare indirect factor of bone quality. TBS predicts fracture independently of BMD as demonstrated from previous studies. The aim of the study is to verify if TBS can be considered as a major CRF of osteoporotic fracture. Existing validated datasets of Caucasian women were analyzed. These datasets stem from different studies performed by the authors of this report or provided to our group. However, the level of evidence of these studies will vary. Thus, the different datasets were weighted differently according to their design. This meta-like analysis involves more than 32000 women (≥50 years) with 2000 osteoporotic fractures from two prospective studies (OFELY&MANITOBA) and 7 crosssectional studies. Weighted relative risk (RR) for TBS was expressed for each decrease of one standard deviation as well as per tertile difference (TBS=1.300 and 1.200) and compared with those obtained for the major CRF included in FRAX®. Overall TBS RR obtained (adjusted for age) was 1.79 [95%CI-1.37-2.37]. For all women combined, RR for fracture for the lowest comparedwith themiddle TBS tertilewas 1.55[1.46- 1.68] and for the lowest compared with the highest TBS tertile was 2.8[2.70-3.00]. TBS is comparable to most of the major CRF (Fig 1) and thus could be used as one of them. Further studies have to be conducted to confirm these first findings.
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The expression of substance P (SP) was studied in sensory neurons of developing chick lumbosacral dorsal root ganglia (DRG) by using a mixture of periodic acid, lysine and paraformaldehyde as fixative and a monoclonal antibody for SP-like immunostaining. The first SP-like-immunoreactive DRG cells appeared first at E5, then rapidly increased in number to reach a peak (88% of ganglion cells) at E8, and finally declined (59% at E12, 51% after hatching). The fall of the SP-like-positive DRG cells resulted from two concomitant events affecting a subset of small B-neurons: a loss of neuronal SP-like immunoreactivity and cell death. After one hindlimb resection at an early (E6) or late (E12) stage of development (that is before or after establishment of peripheral connections), the DRG were examined 6 days later. In both cases, a drastic neuronal death occurred in the ispilateral DRG. However, the resection at E6 did not change the percentage of SP-like-positive neurons, while the resection at E12 severely reduced the proportion of SP-like-immunoreactive DRG cells (25%). In conclusion, connections established between DRG and peripheral target tissues not only promote the survival of sensory neurons, but also control the maintenance of SP-like-expression. Factors issued from innervated targets such as NGF would support the survival of SP-expressing DRG cells and enhance their SP content while other factors present in skeletal muscle or skin would hinder SP expression and therefore lower SP levels in a subset of primary sensory neurons.
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Durante oito meses, foram estudados, em casa de vegetação, os efeitos da aplicação de CaF2 (p.a.) e de CaCO3 (p.a.) sobre a concentração de Al e de outros elementos químicos na solução percolada de amostras de um solo ácido, coletado na região de Piracicaba, SP. Os valores de pH aumentaram na solução percolada de amostras de solos que receberam tanto CaCO3 como CaF2. Os tratamentos com CaF2 foram mais eficientes na retirada de Al do solo do que os tratamentos com CaCO3. Na testemunha e nos tratamentos com CaCO3, a maior parte do Al estava, respectivamente, na forma livre Al3+ ou formando complexos Al-OH, ao passo que, nos tratamentos com CaF2 , mais de 99,5% do Al estava complexado com o fluoreto.
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Receptor activity modifying proteins RAMP1, RAMP2, and RAMP3 are responsible for defining affinity to ligands of the calcitonin receptor-like receptor (CRLR). It has also been proposed that receptor activity-modifying proteins (RAMP) are molecular chaperones required for CRLR transport to the cell surface. Here, we have studied the respective roles of CRLR and RAMP in transporting CRLR/RAMP heterodimers to the plasma membrane by using a highly specific binding assay that allows quantitative detection of cell surface-expressed CRLR or RAMP in the Xenopus oocytes expression system. We show that: (i) heterodimer assembly is not a prerequisite for efficient cell surface expression of CRLR, (ii) N-glycosylated RAMP2 and RAMP3 are expressed at the cell surface and their transport to the plasma membrane requires N-glycans, (iii) RAMP1 is not N-glycosylated and is transported to the plasma membrane only upon formation of heterodimers with CRLR, and (iv) introduction of N-glycosylation sites in the RAMP1 sequence (D58N/G60S, Y71N, and K103N/P105S) allows cell surface expression of these mutants at levels similar to that of wild-type RAMP1 co-expressed with CRLR. Our data argue against a chaperone function for RAMP and identify the role of N-glycosylation in targeting these molecules to the cell surface.
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Human cytomegalovirus (CMV) infection may be a serious complication related to immunosuppression after solid organ transplantation. Due to their cytotoxicity, T-cells and natural killer (NK) cells target and clear the virus from CMV-infected cells. Although immunosuppressive drugs suppress T-cell proliferation and activation, they do not affect NK cells that are crucial for controlling the infection. The regulation of NK cells depends on a wide range of activating and inhibitory receptors such as the family of killer-cell immunoglobulin-like receptors (KIRs). Several human genetic studies have demonstrated the association of KIR genes with the clearance of infections. Since the respective activities of the different KIR proteins expressed by NK cells during CMV infection have not been extensively studied, we analyzed the expression of KIRs in a cohort of 22 CMV-IgG(+) renal transplant patients at the time of CMV reactivation, after antiviral therapy and 6 months later. Our data revealed a marked expression of KIR3DL1 during the acute phase of the reactivation. We set up an in vitro model in which NK cells, derived either from healthy donors or from transplanted patients, target allogeneic fibroblasts, CMV-infected or uninfected. Our results demonstrate a significant correlation between the lysis of CMV-infected fibroblasts and the expression of KIR3DL1. Blocking experiments with antibodies to MHC-I, to NKG2D and to NKG2C confirmed the importance of KIR3DL1. Consequently, our results suggest that KIR proteins and especially KIR3DL1 could play an important role during CMV-infection or CMV reactivation in immunosuppressed patients.
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Em solos com baixos teores de silício (Si) "disponível", a adubação com silicato de cálcio (CaSiO3) pode melhorar as características químicas do solo, tais como o pH, o Ca trocável e o Si "disponível". Efeito na produtividade do arroz também pode ocorrer em decorrência do aumento da resistência ao acamamento e área fotossintética. Neste trabalho, objetivou-se avaliar a disponibilidade do Si em solos de cerrado. O experimento foi realizado em casa de vegetação com a cultura do arroz de sequeiro, e os tratamentos foram cinco doses de Si (0, 120, 240, 480 e 960 kg ha-1), aplicadas na forma de silicato de cálcio, e quatro solos: Latossolo Vermelho-Escuro álico (LEa), Latossolo Vermelho-Amarelo álico (LVa), Latossolo Roxo distrófico (LRd) e Areia Quartzosa álica (AQa). O delineamento experimental foi o inteiramente casualizado com quatro repetições. Avaliou-se o efeito do silicato de cálcio nos teores de Si, Ca e pH do solo e no rendimento de grãos de arroz. Observou-se aumento nos teores de Ca e nos valores de pH do solo. A recuperação do Si aplicado variou segundo a classe de solo e a dose aplicada. O teor de Si "disponível" no solo variou na ordem LRd > LEa = LVa > AQa. O nível de suficiência de Si no solo foi de 9,8 mg dm-3 para atingir 90% da produção máxima.
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Modern scholarship often discusses Roman women in terms of their difference from their male counterparts, frequently defining them as 'other'. This book shows how Roman male writers at the turn of the first century actually described women as not so different from men: the same qualities and abilities pertaining to the domains of parenthood, intellect and morals are ascribed by writers to women as well as to men. There are two voices, however: a traditional, ideal voice and an individual, realistic voice. This creates a duality of representations of women, which recurs across literary genres and reflects a duality of mentality. How can we interpret the paradoxical information about Roman women given by the male-authored texts? How does this duality of mentality inform us about gender roles and gender hierarchy? This work analyses well-known, as well as overlooked, passages from the writings of Pliny the Younger, Tacitus, Suetonius, Quintilian, Statius, Martial and Juvenal and sheds new light on Roman views of women and their abilities, on the notions of private and public and on conjugal relationships. In the process, the famous sixth satire of Juvenal is revisited and its topic reassessed, providing further insights into the complex issues of gender roles, marriage and emotions. By contrasting representations of women across a broad spectrum of literary genres, this book provides consistent findings that have wide significance for the study of Latin literature and the social history of the late first and early second centuries.