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981.
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Bento JL Palmer ND Zhong M Roh B Lewis JP Wing MR Pandya H Freedman BI Langefeld CD Rich SS Bowden DW Mychaleckyj JC 《Genomics》2008,92(4):226-234
Human chromosome 20q12-q13.1 has been linked to type 2 diabetes mellitus (T2DM) in multiple studies. We screened a 5.795-Mb region for diabetes-related susceptibility genes in a Caucasian cohort of 310 controls and 300 cases with T2DM and end-stage renal disease (ESRD), testing 390 SNPs for association with T2DM-ESRD. The most significant SNPs were found in the perigenic regions: HNF4A (hepatocyte nuclear factor 4alpha), SLC12A5 (potassium-chloride cotransporter member 5), CDH22 (cadherin-like 22), ELMO2 (engulfment and cell motility 2), SLC13A3 (sodium-dependent dicarboxylate transporter member 3), and PREX1 (phosphatidylinositol 3,4,5-triphosphate-dependent RAC exchanger 1). Haplotype analysis found six haplotype blocks globally associated with disease (p<0.05). We replicated the PREX1 SNP association in an independent case-control T2DM population and inferred replication of CDH22, ELMO2, SLC13A3, SLC12A5, and PREX1 using in silico perigenic analysis of two T2DM Genome-Wide Association Study data sets. We found substantial heterogeneity between study results. 相似文献
984.
Kok SH Gambari R Chui CH Yuen MC Lin E Wong RS Lau FY Cheng GY Lam WS Chan SH Lam KH Cheng CH Lai PB Yu MW Cheung F Tang JC Chan AS 《Bioorganic & medicinal chemistry》2008,16(7):3626-3631
Phthalic anhydride is a highly toxic substance, facing, however, the problem of hydrolysis. In fact, it is rapidly hydrolyzed in aqueous medium, generating phthalic acid as the final product, which is almost harmless to viable cells. Here we describe the 'one pot' condensation reaction for the synthesis of phthalic imide derivative (benzothiazole containing phthalimide), exhibiting in vitro cytotoxic potential on human cancer cell lines. We further demonstrated that both caspase-dependent and -independent pathways are involved in our novel benzothiazole containing phthalimide induced apoptosis on cancer cells. 相似文献
985.
The crystal structure of the catalytic α−subunit of the DNA polymerase III (PolIIIα) holoenzyme bound to primer-template DNA and an incoming deoxy-nucleoside 5′-triphosphate has been determined at 4.6-Å resolution. The polymerase interacts with the sugar-phosphate backbone of the DNA across its minor groove, which is made possible by significant movements of the thumb, finger, and β-binding domains relative to their orientations in the unliganded polymerase structure. Additionally, the DNA and incoming nucleotide are bound to the active site of PolIIIα nearly identically as they are in their complex with DNA polymerase β, thereby proving that the eubacterial replicating polymerase, but not the eukaryotic replicating polymerase, is homologous to DNA polymerase β. Finally, superimposing a recent structure of the clamp bound to DNA on this PolIIIα complex with DNA places a loop of the β-binding domain into the appropriate clamp cleft and supports a mechanism of polymerase switching. 相似文献
986.
Urea‐Modified Carbon Nitrides: Enhancing Photocatalytic Hydrogen Evolution by Rational Defect Engineering 下载免费PDF全文
Vincent Wing‐hei Lau Victor Wen‐zhe Yu Florian Ehrat Tiago Botari Igor Moudrakovski Thomas Simon Viola Duppel Elise Medina Jacek K. Stolarczyk Jochen Feldmann Volker Blum Bettina V. Lotsch 《Liver Transplantation》2017,7(12)
The primary amine groups on the heptazine‐based polymer melon, also known as graphitic carbon nitride (g‐C3N4), can be replaced by urea groups using a two‐step postsynthetic functionalization. Under simulated sunlight and optimum Pt loading, this urea‐functionalized carbon nitride has one of the highest activities among organic and polymeric photocatalysts for hydrogen evolution with methanol as sacrificial donor, reaching an apparent quantum efficiency of 18% and nearly 30 times the hydrogen evolution rate compared to the nonfunctionalized counterpart. In the absence of Pt, the urea‐derivatized material evolves hydrogen at a rate over four times that of the nonfunctionalized one. Since “defects” are conventionally accepted to be the active sites in graphitic carbon nitride for photocatalysis, the work here is a demonstrated example of “defect engineering,” where the catalytically relevant defect is inserted rationally for improving the intrinsic, rather than extrinsic, photocatalytic performance. Furthermore, the work provides a retrodictive explanation for the general observation that g‐C3N4 prepared from urea performs better than those prepared from dicyandiamide and melamine. In‐depth analyses of the spent photocatalysts and computational modeling suggest that inserting the urea group causes a metal‐support interaction with the Pt cocatalyst, thus facilitating interfacial charge transfer to the hydrogen evolving centers. 相似文献
987.
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Robert W. Engelman Katsuhiko Machida Ross E. Longley Wing T. Liu Liem Q. Trang Robert A. Good Noorbibi K. Day 《In vitro cellular & developmental biology. Plant》1986,22(5):273-279
Summary A new feline lymphoma-derived cell line, designated BKD, was isolated from an anterior mediastinal tumor. Cells of this line
were characterized as lymphoid based on morphology, the lack of intracellular esterase and peroxidase activity, and absence
of phagocytic function. In contrast with other established feline lymphoma-derived cell lines, cells of the BKD line lack
characteristics of both feline T-cells and B-cells in that they neither form rosettes with guinea pig erythrocytes nor have
demonstrable surface or cytoplasmic immunoglobulin. Approximately one third of BKD cells form EAC rosettes, a significant
number of rosette forming cells (p=0.0001) when compared to background sheep E-rosetting activity. In addition, a consistently titratable level of interleukin-2-like
activity was produced when BKD cells were coincubated with concanavalin A and phorbol-12-myristate-13-acetate. Chromosome
analysis showed that a majority of BKD cells are diploid. This new cell line has been continuously replicating in culture
for over one year and produces feline leukemia virus as demonstrated by several analyses.
This research was aided by grants AI-22360 and CA-34103 from the National Institutes of Health and by grant IM-298 from the
American Cancer Society. 相似文献
990.
Design and Demonstration of Insect Mimicking Foldable Artificial Wing Using Four-Bar Linkage Systems
In this work, we develop an artificial foldable wing that mimics the hind wing of a beetle (Allomyrina dichotoma). In real flight, the beetle unfolds forewings and hind wings, and maintains the unfolded configuration unless it is exhausted. The artificial wing has to be able to maintain a fully unfolded configuration while flapping at a desirable flapping frequency. The artificial foldable hind wing developed in this work is based on two four-bar linkages which adapt the behaviors of the beetle's hind wing. The four-bar-linkages are designed to mimic rotational motion of the wing base and the vein folding/unfolding motion of the beetle's hind wing. The behavior of the artificial wings, which are installed in a flapping-wing system, is observed using a high-speed camera. The observation shows that the wing could maintain a fully unfolded configuration during flapping motion. A series of thrust measurements are also conducted to estimate the force generated by the flapping-wing system with foldable artificial wings. Although the artificial foldable wings give added burden to the flapping-wing system because of its weight, the thrust measurement results show that the flapping-wing system could still generate reasonable thrust. 相似文献