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51.
Kwak SJ Paeng J Kim do H Lee SH Nam BY Kang HY Li JJ Jung DS Han SH Ryu DR Park JT Chang TI Yoo TH Han DS Kang SW 《Apoptosis : an international journal on programmed cell death》2011,16(5):478-490
The kallikrein-kinin system (KKS) serves as the physiologic counterbalance to the renin-angiotensin system. This study was conducted to examine the changes in the expression of KKS components in podocytes under diabetic conditions and to elucidate the functional role of bradykinin (BK) in diabetes-associated podocyte apoptosis. Thirty-two rats were injected with either diluent (n = 16, C) or with streptozotocin intraperitoneally (n = 16, DM), and 8 rats from each group were treated with BK infusion for 6 weeks. Immortalized mouse podocytes were cultured in media containing 5.6 mmol/l glucose (NG), NG + 10(-7) mol/l AII (AII), or 30 mmol/l glucose (HG) with or without 10(-8) mol/l BK. Urinary albumin excretion was significantly higher in DM rats, and this increase was ameliorated by BK. Not only kininogen, kallikrein, and BK B1- and B2-receptor expression but also BK levels were significantly decreased in DM glomeruli and in cultured podocytes exposed to HG. The changes in the expressions of apoptosis-related molecules and the increase in the number of apoptotic cells in DM glomeruli as well as in HG- and AII-stimulated podocytes were significantly abrogated by BK. The suppressed KSS within podocytes under diabetic condition was associated with podocyte apoptosis, suggesting that BK may be beneficial in preventing podocyte loss in diabetic nephropathy. 相似文献
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Epstein-Barr virus (EBV) is associated with human cancers such as nasopharyngeal carcinoma, Burkitt’s lymphoma, Hodgkin’s
disease, and gastric carcinoma (GC). EBV is associated with about 10% of all GC cases globally. EBV-associated GC has distinct
features from EBV-negative GC. However, it is still unclear if EBV infection has any effect on GC chemoresistance. Cell proliferation
assay, cell cycle analysis, and active caspase Western blot revealed that the EBV-positive GC cell line (AGS-EBV) showed chemoresistance
to docetaxel compared to the EBV-negative GC cell line (AGS). Docetaxel treatment increased expression of Bax similarly in
AGS and AGS-EBV cell lines. However, Bcl-2 induction was markedly higher in AGS-EBV cells, after docetaxel treatment. Although
docetaxel increased the expression of p53 to a similar extent in both cell lines, induction of p21 in AGS-EBV cells was lower
than in AGS cells. Furthermore, expression of survivin was higher in AGS-EBV cells than in AGS cells following docetaxel treatment
as well as at basal state. EBVlytic gene expression was induced by docetaxel treatment in AGS-EBV cells. The results suggest
that EBV infection and lytic induction confers chemoresistance to GC, possibly by regulating cellular and EBV latent and lytic
gene expression. 相似文献
54.
Theresa Ohlig Do Viet Le Andreas Gardemann Carmen Wolke Sarah Gürtler Daniela Peter Lorenz Schild Uwe Lendeckel 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2018,1863(4):379-387
The mitochondrial phospholipid cardiolipin (CL) has been implicated with mitochondrial morphology, function, and cell proliferation. Changes in CL are often paralleled by changes in the lipid environment of mitochondria that may contribute to mitochondrial function and proliferation. This study aimed to separate the effects of CL content and CL composition from cellular free fatty acid distribution on bioenergetics and proliferation in C6 glioma cells. To this end, cardiolipin synthase and the CL remodelling enzyme, tafazzin, were knocked-down by siRNA in C6 cells. After 72?h of cultivation, we analysed CL composition by means of LC/MS/MS, distribution of cellular fatty acids by means of gas chromatography, and determined oxygen consumption and proliferation. Knock-down of cardiolipin synthase affected the cellular CL content in the presence of linoleic acid (LA) in the culture medium. Knock-down of tafazzin had no consequence with respect to the pattern of cellular fatty acids but caused a decrease in cell proliferation. It significantly changed the distribution of molecular CL species, increased CL content, decreased oxygen consumption, and decreased cell proliferation when cultured in the presence of linoleic acid (LA). The addition of linoleic acid to the culture medium caused significant changes in the pattern of cellular fatty acids and the composition of molecular CL species. These data suggest that tafazzin is required for efficient bioenergetics and for proliferation of glioma cells. Supplementation of fatty acids can be a powerful tool to direct specific changes in these parameters. 相似文献
55.
Mikdat Doğanlar 《Zoology in the Middle East.》2018,64(3):238-243
Two new species of torymids, Pseudotorymus hasanberkayi sp. n. and Microdontomerus kahramanmarasensis sp. n. (Hymenoptera: Torymidae), were reared from flower heads of Echinops orientalis Trautvetter (Asteraceae) collected in Kahramanmara? province, south-eastern Turkey. The new species are described and their diagnostic characters are illustrated.http://www.zoobank.org/urn:lsid:zoobank.org:pub:848B4E9D-AE8A-4EF8-8072-1F28BE21ADA1 相似文献
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58.
Hee Jae Hwang Joo Sung Kim Wook Kim Hyunwoo Park Divij Bhatia Eunsong Jee Yoon Sun Chung Do Hwan Kim Dukhyun Choi 《Liver Transplantation》2019,9(17)
A mechanosensitive, visco‐poroelastic polymer ion pump that can rapidly establish a dense electrical double layer via mechanical pressure, thereby significantly enhancing output performance of an ionic triboelectric nanogenerator (iTENG), is described. A working mechanism of an iTENG using a highly mechanosensitive, visco‐poroelastic ion pump is suggested and the optimal characteristics of the polymer ion pump are reported by investigating optical, mechanical, electrical, and electrochemical properties. Surprisingly, the pressure sensitivity of the iTENG reaches 23.3 V kPa?1, which is tens of times the record value. To achieve controlled high‐frequency pulses from an iTENG, kinematic systems using a gear train and a cam are integrated with a single grounded iTENG, which produces a maximum of 600 V and 22 mA (≈2.2 W cm?2) at an input frequency of 1.67 Hz; after power transforming, those values are converted to 1.42 V and 225 mA. A capacitor of 1 mF can be fully charged to 2 V in only 60 s, making it possible to continuously operate a wireless‐communicating self‐powered humidity sensor. Also, due to the high transparency and deformability of the polymer ion pump, a self‐powered transparent tactile sensor is successfully assembled using a 5 × 5 iTENG array. 相似文献
59.
Do Quang Binh László E. Heszky Gabor Gyulai Anikó Csillag 《Plant Cell, Tissue and Organ Culture》1992,29(2):75-82
Cells of a 2-year-old suspension culture of rice (Oryza sativa L.), grown under 1.5% NaCl stress for 3 months, gave rise to plants through embryogenesis in different saline conditions. The high regeneration potential (59.6%) on salt-free medium decreased rapidly with increasing concentration of salt in the regeneration medium. At 1.25% NaCl, healthy shoots were developed in 14.9% of the cultures. Under 1.5% salt stress, embryo formation and embryo germination (6.1%) was observed but further development into plants was inhibited. Cells not pretreated with salt produced plants at a low frequency (2.6–4.2%) both in salt-free and low saline condition (0.75–1% NaCl). Cells pretreated for 3 months with 0.75% salt did not give rise to plants on all tested media. Plants regenerated from the salt-stressed cultures were transferred to soil and grew to maturity in a greenhouse.Abbreviations BA
6-benzyladenine
- CH
casein hydrolysate
- 2,4-D
2,4-dichlorophenoxyacetic acid
- NAA
1-naphthaleneacetic acid 相似文献
60.