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901.
Activated rheumatoid arthritis (RA) fibroblast-like synoviocytes (RAFLSs) play a central role in both initiating and driving
RA. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been documented to induce apoptosis only in a small
proportion of RAFLSs, which is followed by an induction of proliferation in surviving cells. Apigenin, a chemopreventive bioflavonoid,
exhibits proapoptotic activity in many types of cells. In the present study, we sought to determine whether apigenin could
enhance the cytotoxic effect of TRAIL on activated RAFLSs. Human RAFLSs isolated from patients with RA were treated with TRAIL
(1 nM), apigenin (20 μM), or their combination, and subjected to apoptosis analysis after a 24-h incubation and proliferation
analysis after a 72-h incubation. Apoptosis assay revealed that TRAIL or apigenin alone induced a marked apoptosis in RAFLS
and their combination yielded a synergistic increase in RAFLS apoptosis. Immunoblotting analysis of apoptosis regulators demonstrated
that combined treatment with apigenin increased caspase-3 expression and activity and decreased the Bcl-2/Bax ratio relative
to treatment with TRAIL alone. The presence of apigenin significantly restrained TRAIL-induced RAFLS proliferation, coupled
with restoration of the expression of two cell-cycle inhibitors p21 and p27. Moreover, the combination with apigenin blunted
TRAIL-induced activation of the phosphatidylinositol 3-kinase (PI3-K)/Akt pathway. Our data collectively demonstrate that
apigenin sensitizes RAFLS to TRAIL-induced apoptosis and counteracts TRAIL-dependent RAFLS proliferation, which is likely
mediated through inactivation of PI3-K/Akt signaling pathway. 相似文献
902.
Yuan Xu Chen Shao Xinpeng Fan Alan Warren Khaled A. S. Al-Rasheid Weibo Song Norbert Wilbert 《Polar Biology》2016,39(8):1439-1453
Antarctica is a remote and isolated biotope which makes it an ideal location for studying new and endemic species. Since there is little literature available on the diversity of ciliates in this area, a taxonomic survey of ciliates from melt-water of Collins glacier, King George Island, was carried out from January to March 2006. As a result, the morphology and infraciliature of five ciliates, including one new species, are described using live observations and silver staining: Gastronauta multistriata nov. spec., Neokeronopsis asiatica Foissner et al., 2010, Paraholosticha muscicola Kahl, 1932, Oxytricha sp., and Cyclidium glaucoma Müller, 1786. Gastronauta multistriata nov. spec. is distinguished from its congeners by the following combination of characters: cell size in vivo on average 80 × 40 μm; 5–9 kineties in left ciliary field; 18–23 kineties in right ciliary field, including 10–12 postoral kineties; 7–10 preoral kineties; dorsal brush along anterior dorsal margin, consisting of 5–8 groups of basal bodies. The only minor differences between the current population of N. asiatica and a previously described Antarctic population are the numbers of caudal cirri (6–10 vs. 8–15) and dorsal kineties (11–13 vs. 12–18). Paraholosticha sterkii is synonymised with P. muscicola. The Antarctic population of C. glaucoma corresponds well with a former population from China, the only difference being the number of kinetids in SK n (11–17 vs. 9–11). This work will contribute to the understanding of ciliate diversity in this little studied area. 相似文献
903.
Sarah O’Connell Darren Lillis Aoife Cotter Siobhan O’Dea Helen Tuite Catherine Fleming Brendan Crowley Ian Fitzgerald Linda Dalby Helen Barry Darragh Shields Suzanne Norris Patrick K. Plunkett Colm Bergin 《PloS one》2016,11(3)
Objectives
Studies suggest 2 per 1000 people in Dublin are living with HIV, the level above which universal screening is advised. We aimed to assess the feasibility and acceptability of a universal opt-out HIV, Hepatitis B and Hepatitis C testing programme for Emergency Department patients and to describe the incidence and prevalence of blood-borne viruses in this population.Methods
An opt-out ED blood borne virus screening programme was piloted from March 2014 to January 2015. Patients undergoing blood sampling during routine clinical care were offered HIV 1&2 antibody/antigen assay, HBV surface antigen and HCV antibody tests. Linkage to care where necessary was co-ordinated by the study team. New diagnosis and prevalence rates were defined as the new cases per 1000 tested and number of positive tests per 1000 tested respectively.Results
Over 45 weeks of testing, of 10,000 patient visits, 8,839 individual patient samples were available for analysis following removal of duplicates. A sustained target uptake of >50% was obtained after week 3. 97(1.09%), 44(0.49%) and 447(5.05%) HIV, Hepatitis B and Hepatitis C tests were positive respectively. Of these, 7(0.08%), 20(0.22%) and 58(0.66%) were new diagnoses of HIV, Hepatitis B and Hepatitis C respectively. The new diagnosis rate for HIV, Hepatitis B and Hepatitis C was 0.8, 2.26 and 6.5 per 1000 and study prevalence for HIV, Hepatitis B and Hepatitis C was 11.0, 5.0 and 50.5 per 1000 respectively.Conclusions
Opt-out blood borne viral screening was feasible and acceptable in an inner-city ED. Blood borne viral infections were prevalent in this population and newly diagnosed cases were diagnosed and linked to care. These results suggest widespread blood borne viral testing in differing clinical locations with differing population demographic risks may be warranted. 相似文献904.
905.
The ayu (Plecoglossus altivelis) is an annual, amphidromous, plecoglossid fish, distributed in Vietnam, China, Taiwan, Korea, and Japan. To date, ayu have been found only in two rivers in northern Vietnam, where little is known about their life history. The Tien Yen River is believed to be the most southwestern habitat for this species. To determine whether newly hatched ayu larvae drift and to understand their downstream migration, intensive surveys were conducted in the Tien Yen River from October to March of 2013–2016. In total, 529 drifting ayu larvae were collected from four of six sampling stations along the river. Thus, ayu reproduction has been confirmed in this river for the first time, where only adult fish had been found previously. However, we did not successfully collect larvae in the eastern branch of the river, which has a hydroelectric dam, suggesting that ayu do not inhabit this branch or else do not reproduce there. The presence of drifting larvae in the western branch from mid-December to late January implies that they spawn from late November to mid-January. Drifting larvae were captured primarily at night, but peak occurrences varied depending upon the day and the sampling station. With the range of body sizes and variable diel abundance patterns, ayu in the Tien Yen River probably employ multiple spawning grounds. This study provides fundamental life history data for the vulnerable ayu populations in northern Vietnam. 相似文献
906.
Jianhui Wu Qingdong Zeng Qilin Wang Shengjie Liu Shizhou Yu Jingmei Mu Shuo Huang Hanan Sela Assaf Distelfeld Lili Huang Dejun Han Zhensheng Kang 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2018,131(7):1481-1496
Key message
NGS-assisted super pooling emerging as powerful tool to accelerate gene mapping and haplotype association analysis within target region uncovering specific linkage SNPs or alleles for marker-assisted gene pyramiding.Abstract
Conventional gene mapping methods to identify genes associated with important agronomic traits require significant amounts of financial support and time. Here, a single nucleotide polymorphism (SNP)-based mapping approach, RNA-Seq and SNP array assisted super pooling analysis, was used for rapid mining of a candidate genomic region for stripe rust resistance gene Yr26 that has been widely used in wheat breeding programs in China. Large DNA and RNA super-pools were genotyped by Wheat SNP Array and sequenced by Illumina HiSeq, respectively. Hundreds of thousands of SNPs were identified and then filtered by multiple filtering criteria. Among selected SNPs, over 900 were found within an overlapping interval of less than 30 Mb as the Yr26 candidate genomic region in the centromeric region of chromosome arm 1BL. The 235 chromosome-specific SNPs were converted into KASP assays to validate the Yr26 interval in different genetic populations. Using a high-resolution mapping population (>?30,000 gametes), we confined Yr26 to a 0.003-cM interval. The Yr26 target region was anchored to the common wheat IWGSC RefSeq v1.0 and wild emmer WEWSeq v.1.0 sequences, from which 488 and 454 kb fragments were obtained. Several candidate genes were identified in the target genomic region, but there was no typical resistance gene in either genome region. Haplotype analysis identified specific SNPs linked to Yr26 and developed robust and breeder-friendly KASP markers. This integration strategy can be applied to accelerate generating many markers closely linked to target genes/QTL for a trait of interest in wheat and other polyploid species.907.
The objective of the present study was to synthesize monomethoxypolyethyleneglycol-5000 cholesteryl ester [PEG–CH] as a cost-effective
substitute for polyethyleneglycol–phosphatidylethanolamine and to evaluate the influence of its incorporation in liposomal
bilayers for surface modification. PEG–CH was synthesized and characterized by infrared (IR), proton nuclear magnetic resonance
spectroscopy (1H NMR), and differential scanning calorimetry (DSC) studies. Influence of incorporation of PEG–CH in liposomes was evaluated
on various parameters such as zeta potential, DSC, and encapsulation efficiency of a hydrophilic drug pentoxyfylline. Conventional
and PEG–CH containing pentoxyfylline liposomes were formulated and their stability was evaluated at 4°C for 3 months. PEG–CH
could be successfully synthesized with good yields and the structure was confirmed by IR, DSC, and 1H NMR. The incorporation of PEG–CH in liposomes resulted in reduction of the zeta potential and broadening of the DSC endotherm.
Furthermore, incorporation of PEG–CH in liposomes decreased the encapsulation efficiency of pentoxifylline in liposomes when
compared to conventional liposomes. Conventional and PEG–CH containing pentoxyfylline liposomes did not show any signs of
pentoxyfylline degradation when stored at 4°C for 3 months. 相似文献
908.
Alcantarea martinellii is described and illustrated as a new species endemic to Serra dos Órgãos, Petrópolis, Rio de Janeiro State, Brazil. The presence of a simple and erect inflorescence concomitant with a conspicuous water impounding rosette is an unreported combination of characters for Alcantarea. This new lithophytic taxon is unique, with no obvious close relative, but it is similar to A. benzingii, A. farneyi, and A. hatschbachii, which also have unbranched inflorescences. 相似文献
909.
Qiuchi Wan Zhuo Zheng Kangyou Huang Erwan Guichoux Rémy J. Petit 《Tree Genetics & Genomes》2017,13(4):73
Subtropical East Asia harbours a large plant diversity that is often attributed to allopatric speciation in this topographically complex region characterized by a relative climate stability. Here, we use observations of Platycarya, a widespread subtropical Asian tree genus, to explore the consequences of past climate stability on species’ evolutionary history in subtropical China. This genus has a controversial taxonomy: while it is now prevailingly treated as monotypic, two species have been originally described, Platycarya strobilacea and P. longipes. Previous information from species distribution models, fossil pollen data and genetic data based on chloroplast DNA (cpDNA) were integrated with newly obtained genetic data from the two putative species. We used both cpDNA (psbA-trnH and trnL-F intergenic spacers, including a partial trnL gene sequence) and nuclear markers. The latter included sequences of the internal transcribed spacer region (ITS1–5.8S–ITS2) of the nuclear ribosomal DNA and random genomic single nucleotide polymorphisms. Using these nuclear genetic markers, we found interspecific genetic divergence fitting with the ‘two species’ scenario and geographically structured intraspecific variation. Using cpDNA markers, we also found geographically structured intraspecific variation. Despite deep inter- and intraspecific genetic divergence, we detected genetic admixture in southwest China. Overall, our findings of genetic divergence within Platycarya support the hypothesis of allopatric speciation. However, episodes of population interconnection were identified, at least in southwest China, suggesting that the genus has had a dynamic population history. 相似文献
910.
Organization and assembly of the TRAPPII complex 总被引:1,自引:0,他引:1
Choi C Davey M Schluter C Pandher P Fang Y Foster LJ Conibear E 《Traffic (Copenhagen, Denmark)》2011,12(6):715-725
Current models suggest that TRAPP tethering complexes exist in two forms. Whereas the seven-subunit TRAPPI complex mediates ER-to-Golgi transport, TRAPPII contains three additional subunits (Trs65, Trs120 and Trs130) and is required for distinct tethering events at Golgi membranes. It is not clear how TRAPPII assembly is regulated. Here, we show that Tca17 is a fourth TRAPPII-specific component, and that Trs65 and Tca17 interact with distinct domains of Trs130 and make different contributions to complex assembly. Whereas Tca17 promotes the stable association of TRAPPII-specific subunits with the core complex, Trs65 stabilizes TRAPPII in an oligomeric form. We show that Trs85, which was previously reported to be a subunit of both TRAPPI and TRAPPII, is not associated with the TRAPPII complex in yeast. However, we find that proteins related to Trs85, Trs65 and Tca17 are part of the same TRAPP complex in mammalian cells. These findings have implications for models of TRAPP complex formation and suggest that TRAPP complexes may be organized differently in yeast and mammals. 相似文献