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Feng Shi WU 《Cell research》2005,15(11):919-922
International non-governmental organizations were among the first international actors that responded to the emergence of AIDS crisis in China. Since 1994, the number of international non-governmental organizations and charitable foundations working in AIDS related issue areas in China has grown steadily and substantially. Despite their organizational differences, most of these non-governmental actors present the characteristics of independent mission, localized practice and diverse working focus. Even though they are constrained by financial and other factors compared with multilateral and bilateral official assistance agencies, they have still played a unique role in fighting against AIDS in China as technical experts, public educators, and civil society supporters.  相似文献   

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INTRODUCTION This research examines a group of international non- governmental organizations (NGOs) and private founda- tions that have worked and/or are still working in HIV/ AIDS prevention related issue areas in China. Main char- acteristics of this tr…  相似文献   

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The villin/gelsolin/fragmin superfamily is a conserved Ca^2+-dependent family of actin-regulating proteins that is widely present both in mammalian and non-mammalian organisms. They have traditionally been characterized by the same core of three or six tandem gelsolin subdomains. The study in vertebrates and lower eukaryotic cells has revealed that the villin/gelsolin/fragmin superfamily of proteins has versatile functions including severing, capping, nucleating or bundling actin filaments. In plants, encouraging progress has been made in this field of research in recent years. This review will summarize the identified plant homologs of villin/gelsolin/fragmin superfamily, thus providing a basis for reflection on their biochemical activities and functions in plants.  相似文献   

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CSN5/JAB1 is a critical subunit of the COP9 signalosome (CSN) and is overexpressed in many human cancers, but little is known about the role of CSN5 in colorectal cancer (CRC). To explore the functional role of CSN5 in colorectal tumorigenesis, we applied siRNA technology to silence CSN5 in HeLa, SW480, HCT116, HT29, and CaCo2 cells. CSN5 knock-down led to reduced β-catenin and phospho-bcatenin levels and this was paralleled by reduced CRC cell proliferation and reduced apoptosis rates, whereas the short-term β-catenin protein stability was enhanced by CSN5 knock-down in SW480 cells. Together, these data implicate the CSN in the pathogenesis of CRC via regulation of the Wnt/β-catenin pathway  相似文献   

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Chromatographic, mass spectrometric and spectroscopic evidence has been obtained for four β-diketones occurring in the leaf waxes of some members of  相似文献   

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The role of dinB gene in the appearing of antibiotics resistance was studied. Plasmid containing multi-copy dinB gene was transfected into E. coli to create an overexpression. The strains carrying multi-copies of dinB gene demonstrate a significant survival advantage over the wild strain. In vitro experiment, the dinB-overexpressed strain evolved resistance within 8 hours, while wild strain could not.In vivo experiment with mice model infected with dinB-overexpressed strain, resistant clones emerged significantly earlier and demonstrated significant higher level of resistance than those infected with the wild control strain. The results showed that dinB gene made a contribution in the appearing of the antibiotics resistance and has a potential as a target for prevention from the appearing of antibiotic resistance.  相似文献   

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NAD plays an essential role in a number of biological processes. A study in this issue of Cell Metabolism (Revollo et al., 2007b) demonstrates that nicotinamide phosphoribosyltransferase (Nampt), also known as PBEF or visfatin, is a secreted enzyme and a source of systemic NAD. The authors show that Nampt-mediated NAD synthesis is necessary for beta cell function, providing fresh insights into the pathophysiology of metabolic diseases.  相似文献   

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Receptor activator of nuclear factor κB (RANK) is one of the proteins in regulation of osteoclastogenesis via RANK/RANKL/OPG. Gene that codes for RANK protein (TNFRSF11A) was associated with osteoporotic fractures in a recent genome-wide association study. As variations in the RANK gene could alter its expression and activity, the aim of our study was to evaluate the influence of four RANK gene polymorphisms on bone mineral density (BMD) and biochemical markers.We evaluated 467 postmenopausal women and 117 elderly men. All subjects were genotyped for the presence of RANK polymorphisms ?670G>C, +34694C>T, +34901G>A and +35966insdelC. BMD and biochemical markers were measured.Significant associations of +35966insdelC with BMD at lumbar spine (BMD-ls), total hip (BMD-th) and femoral neck (BMD-fn) were found in postmenopausal women (p = 0.020, 0.024 and 0.034), but not in men. Significant gene–gene interaction was proved for two RANK polymorphisms in combination with OPG and RANKL polymorphisms studied previously in postmenopausal women. Firstly, RANK/RANKL (+34901G>A/?290C>T) combination was associated with BMD-fn, BMD-th and BMD-ls (p = 0.034, 0.016 and 0.050), and secondly, RANK/OPG combination (+35966insdelC/K3N) showed influence on BMD-fn and BMD-ls (p = 0.043 and 0.039).Our results suggest that gene–gene interactions between RANK and OPG, and RANK and RANKL influence BMD in postmenopausal women.  相似文献   

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《Organogenesis》2013,9(2):92-99
Wnt/β-catenin signaling has come to the forefront of liver biology in recent years. This pathway regulates key pathophysiological events inherent to the liver including development, regeneration, and cancer, by dictating several biological processes such as proliferation, apoptosis, differentiation, adhesion, zonation and metabolism in various cells of the liver. This review will examine the studies that have uncovered the relevant roles of Wnt/β-catenin signaling during the process of liver development. We will discuss the potential roles of Wnt/β-catenin signaling during the phases of development, including competence, hepatic induction, expansion, and morphogenesis. In addition, we will discuss the role of negative and positive regulation of this pathway and how the temporal expression of Wnt/β-catenin can direct key processes during hepatic development. We will also identify some of the major deficits in the current understanding of the role of Wnt/β-catenin signaling in liver development in order to provide a perspective for future studies. Thus, this review will provide a contextual overview of the role of Wnt/β-catenin signaling during hepatic organogenesis.  相似文献   

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Characters of Pogonophora, including Perviata (Frenulata and Scleronlinida) and Vestimentifera, are critically analysed and the characters re‐evaluated with respect to their reliability in determining relationships with Annelida‐Polychaeta in general and with Oweniidae in particular, as well as with Oligomera. In addition to several differentiations which possibly express parallelisms, only a few characters reflect trustworthy information based on the current state of knowledge. These, however, still include ‘sets’ of both Annelida‐Polychaeta features and Oligomera features; despite the more recent trend to regard the Pogonophora as annelids, no unequivocal preference can be given as to which of these ‘sets’ is convergent/homoplastic. The intra‐epithelial nervous system without true cerebral ganglia, typical of Epineuralia as well as Pogonophora and Oweniidae, is here considered to represent the paedomorphic peripheral‐epidermal larval system of Gastroneuralia in contrast to the ganglionated gastroneural adult system.  相似文献   

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Chinese nongovernmental organizations (NGOs) have played a significant role in the battle against AIDS in the People's Republic of China. This article provides a brief overview of the structure of these organizations, as well as an analysis of their principle accomplishments. Of great significance in this analysis is the fact that Chinese NGOs have effectively dealt with many sensitive health education areas that government authorities have felt reluctant to handle directly. As such, they have provided an indispensable component in the HIV/AIDS prevention and control calculus on the mainland.  相似文献   

14.
Glioblastoma (GBM) is the most aggressive of primary brain tumors. Despite the progress in understanding the biology of the pathogenesis of glioma made during the past decade, the clinical outcome of patients with GBM remains still poor. Deregulation of many signaling pathways involved in growth, survival, migration and resistance to treatment has been implicated in pathogenesis of GBM. One of these pathways is phosphatidylinositol-3 kinases (PI3K)/protein kinase B (AKT)/rapamycin-sensitive mTOR-complex (mTOR) pathway, intensively studied and widely described so far. Much less attention has been paid to the role of glycogen synthase kinase 3 β (GSK3β), a target of AKT. In this review we focus on the function of AKT/GSK3β signaling in GBM.  相似文献   

15.

Objectives

People living with HIV/AIDS (PLWHA) who develop tuberculosis disease are at greater mortality-risk. This study aimed to assess tuberculosis disease incidence among all PLWHA in Israel and identify populations at high-risk for developing tuberculosis.

Design and Methods

Retrospective cohort-study based on the National HIV and Tuberculosis Registries, which were cross-matched and followed for the last 28-years. PLWHA who developed tuberculosis were compared to those who did not by the Cox-proportional analysis to generate hazard-ratios, and survival-analysis was performed by Log-Rank test.

Results

Of all the 6579 PLWHA reported between 1983 and 2010, corresponding to 55737 person-years, 384 (5.8%) developed tuberculosis. Of those, 14 were Israeli-born and 370 were non-Israeli born. The overall tuberculosis incidence-density was 6.9 cases/1000 person-years (95% CI 1.8–12.0). The cumulative tuberculosis-incidence among PLWHA in 2010 was 586 times higher than in HIV-negative individuals (3400 and 5.8 cases per 100000 population, respectively). Higher hazard-ratios to developing tuberculosis were found in migrant citizens PLWHA who were males, non-Israeli born, those who were diagnosed with HIV/AIDS after 1997, those who originated in high-tuberculosis prevalence country and those who acquired HIV by heterosexual or drug-injection transmission. PLWHA who developed tuberculosis had higher odds of dying than other PLWHA (36.5% and 16.6%, respectively, p<0.001, odds ratio = 2.8, 95% confidence-interval 2.3–3.6). In survival-analysis, time to develop tuberculosis was shorter among males than females, in PLWHA who were reported with HIV after 1997, in heterosexual who originated in high-tuberculosis countries, followed by injecting drug-users, heterosexual from low-tuberculosis burden countries and men who have sex with men.

Conclusion

Tuberculosis-incidence is higher among non-Israeli born PLWHA, with decreasing trends from 1991. Despite the moderate TB-rate disease among PLWHA, it remains an important cause for severe morbidity and mortality. Tuberculosis in PLWHA reflects mainly the tuberculosis-burden in the originating country and possibly also the mode of HIV-transmission.  相似文献   

16.
Discrimination of stable isotopes of carbon (δ13C) and nitrogen (δ15N) was examined for the amphipod Allorchestes compressa Dana using controlled laboratory experiments. Amphipods were fed exclusively on single diets (fresh or decomposed macroalgae or seagrass) for three weeks. Macrophyte type (i.e. seagrass, brown algae or red algae) had a greater influence on the stable isotope ratios of A. compressa than the state of decomposition of the macrophyte material. The experiments revealed that δ13C in A. compressa stabilised at values lower than those of the diets, which contrasts to the general assumption that consumer-diet discrimination of δ13C ranges from 0 to + 1‰. Amphipods fed on seagrass yielded the lowest δ13C values, which were 9 to 10‰ lower than their diet, while amphipods fed on macroalgae had values 2 to 4‰ lower than their diet. In addition, contrary to the general assumption that consumer-diet discrimination of δ15N ranges from + 3 to + 5‰, discrimination of δ15N was as low as − 1 and + 1 when A. compressa was fed on brown and red algae, respectively, but as high as + 3‰ when fed on seagrass. The results show that discrimination of stable isotopes of carbon and nitrogen can vary considerably depending on the food source, demonstrating that validation of assumptions about discrimination are critical for interpreting stable isotope data from field studies.  相似文献   

17.
Ethanol-hypersensitive strains (ets mutants), unable to grow on media containing 6% ethanol, were isolated from a sample of mutagenized Schizosaccharomyces pombe wild-type cells. Genetic analysis of these ets strains demonstrated that the ets phenotype is associated with mutations in a large set of genes, including cell division cycle (cdc) genes, largely non-overlapping with the set represented by the temperature conditional method; accordingly, we isolated some ets non-ts cdc mutants, which may identify novel essential genes required for regulation of the S. pombe cell cycle. Conversely, seven well characterized ts cdc mutants were tested for their ethanol sensitivity; among them, cdc1–7 and cdc13–117 exhibited a tight ets phenotype. Ethanol sensitivity was also tested in strains bearing different alleles of the cdc2 gene, and we found that some of them were ets, but others were non-ets; thus, ethanol hypersensitivity is an allele-specific phenotype. Based on the single base changes found in each particular allele of the cdc2 gene, it is shown that a single amino acid substitution in the p34cdc2 gene product can produce this ets phenotype, and that ethanol hypersensitivity is probably due to the influence of this alcohol on the secondary and/or tertiary structure of the target protein. Ethanol-dependent (etd) mutants were also identified as mutants that can only be propagated on ethanol-containing media. This novel type of conditional phenotype also covers many unrelated genes. One of these etd mutants, etd1-1, was further characterized because of the lethal cdc phenotype of the mutant cells under restrictive conditions (absence of ethanol). The isolation of extragenic suppressors of etd1-1, and the complementation cloning of a DNA fragment encompassing the etd1 + wild-type gene (or an extragenic multicopy suppressor) demonstrate that current genetic techniques may be applied to mutants isolated by using ethanol as a selective agent.  相似文献   

18.
The appearance of vitiligo and spontaneous regression of the primary lesion in melanoma patients illustrate a relationship between tumor immunity and autoimmunity. T lymphocytes play a major role both in tumor immunity and autoimmunity. CD28, Cytotoxic T lymphocyte antigen 4 (CTLA4) and inducible costimulator (ICOS) molecules are important secondary signal molecules in the T lymphocyte activation. Single nucleotide polymorphisms (SNPs) in the CD28/CTLA4/ICOS gene region were reported to be associated with several autoimmune diseases including, type-1 diabetes, SLE, autoimmune thyroid diseases and celiac disease. In this study, we investigated the association of SNPs in the CD28, CTLA4 and ICOS genes with the risk of melanoma. We also assessed the prognostic effect of the different polymorphisms in melanoma patients. Twenty-four tagging SNPs across the three genes and four additional SNPs were genotyped in a cohort of 763 German melanoma patients and 734 healthy German controls. Influence on prognosis was determined in 587 melanoma cases belonging to stage I or II of the disease. In general, no differences in genotype or allele frequencies were detected between melanoma patients and controls. However, the variant alleles for two polymorphisms in the CD28 gene were differentially distributed in cases and controls. Similarly no association of any polymorphism with prognosis, except for the rs3181098 polymorphism in the CD28 gene, was observed. In addition, individuals with AA genotype for rs11571323 polymorphism in the ICOS gene showed reduced overall survival. However, keeping in view the correction for multiple hypothesis testing our results suggest that the polymorphisms in the CD28, CTLA4 and ICOS genes at least do not modulate risk of melanoma and nor do those influence the disease prognosis in the investigated population.  相似文献   

19.
In voltage-dependent Ca2+ channels, the α1 and β subunits interact via two cytoplasmic regions defined as the Alpha Interaction Domain (AID) and Beta Interaction Domain (BID). Several novel amino acids for that interaction have now been mapped in both domains by point mutations. It was found that three of the nine amino acids in AID and four of the eight BID amino acids tested were essential for the interaction. Whereas the important AID amino acids were clustered around five residues, the important BID residues were more widely distributed within a larger 16 amino acid sequence. The affinity of the AIDA GST fusion protein for the four interacting β1b BID mutants was not significantly altered compared with the wild-type β1b despite the close localization of mutated residues to disruptive BID amino acids. Expression of these interactive β mutants with the full-length α1A subunit only slightly modified the stimulation efficiency when compared with the wild-type β1b subunit. Our data suggest that non-disruptive BID sequence alterations do not dramatically affect the β subunit-induced current stimulation.  相似文献   

20.
Lack of dopamine production and neurodegeneration of dopaminergic neurons in the substantia nigra are considered as the major characteristics of Parkinson's disease, a prevalent movement disorder worldwide. DJ-1 mutation leading to loss of its protein functions is a genetic factor of PD. In this study, our results illustrated that DJ-1 can directly interact with Ca2+/calmodulin-dependent protein kinase kinase β (CaMKKβ) and modifies the cAMP-responsive element binding protein 1 (CREB1) activity, thus regulates tyrosine hydroxylase (TH) expression. In Dj-1 knockout mouse substantia nigra, the levels of TH and the phosphorylation of CREB1 Ser133 are significantly decreased. Moreover, Dj-1 deficiency suppresses the phosphorylation of CaMKIV (Thr196/200) and CREB1 (Ser133), subsequently inhibits TH expression in vitro. Furthermore, Knockdown of Creb1 abolishes the effects of DJ-1 on TH regulation. Our data reveal a novel pathway in which DJ-1 regulates CaMKKβ/CaMKIV/CREB1 activities to facilitate TH expression.  相似文献   

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