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991.
992.
Köttgen A Yang Q Shimmin LC Tin A Schaeffer C Coresh J Liu X Rampoldi L Hwang SJ Boerwinkle E Hixson JE Kao WH Fox CS 《PloS one》2012,7(5):e38311
993.
994.
ABSTRACT: BACKGROUND: The purpose of this study was to investigate the relationship among work stress, sex life satisfaction, and mental health of married nurses. Demographic information, work stress, sex life satisfaction, sexual desire and mental health measured using the Chinese Health Questionnaire, data were collected from 100 married nurses in Taiwan. FINDINGS: Sex life satisfaction and age were negatively correlated, but sex life satisfaction and sexual desire were positively correlated. The mental health of over-committed nursing staff was not affected. Higher reward for effort was positively correlated with sex life satisfaction. CONCLUSIONS: No matter whether job stress was high or low, receiving a higher reward for effort led to better sex life satisfaction, which had a satisfying positive effect on the nurses' lives. To improve nursing care quality at the hospital, nursing administrators should assist nurses in confronting work stress via positive adjustment, which is associated with the nurses' sexual harmony, and quality of life. 相似文献
995.
Jorgensen TJ Ruczinski I Yao Shugart Y Wheless L Berthier Schaad Y Kessing B Hoffman-Bolton J Helzlsouer KJ Kao WH Francis L Alani RM Strickland PT Smith MW Alberg AJ 《Cancer epidemiology》2012,36(5):e288-e293
Introduction: A personal history of basal cell carcinoma (BCC) is associated with increased risk of other malignancies, but the reason is unknown. The hedgehog pathway is critical to the etiology of BCC, and is also believed to contribute to susceptibility to other cancers. This study tested the hypothesis that hedgehog pathway and pathway-related gene variants contribute to the increased risk of subsequent cancers among those with a history of BCC. Methods: The study was nested within the ongoing CLUE II cohort study, established in 1989 in Washington County, Maryland, USA. The study consisted of a cancer-free control group (n=2296) compared to three different groups of cancer cases ascertained through 2007, those diagnosed with: (1) Other (non-BCC) cancer only (n=2349); (2) BCC only (n=534); and (3) BCC plus other cancer (n=446). The frequencies of variant alleles were compared among these four groups for 20 single nucleotide polymorphisms (SNPs) in 6 hedgehog pathway genes (SHH, IHH, PTCH2, SMO, GLI1, SUFU), and also 22 SNPs in VDR and 8 SNPs in FAS, which have cross-talk with the hedgehog pathway. Results: Comparing those with both BCC and other cancer versus those with no cancer, no significant associations were observed for any of the hedgehog pathway SNPs, or for the FAS SNPs. One VDR SNP was nominally significantly associated with the BCC cancer-prone phenotype, rs11574085 [per minor allele odds ratio (OR) 1.38, 95% confidence interval (CI) 1.05-1.82; p-value=0.02]. Conclusion: The hedgehog pathway gene SNPs studied, along with the VDR and FAS SNPs studied, are not strongly associated with the BCC cancer-prone phenotype. 相似文献
996.
In the present study, the role of nitric oxide (NO) in the regulation of lateral root (LR) formation in rice was examined.
Application of sodium nitroprusside (SNP; a NO donor) and indole-3-butyric acid (IBA; a naturally occurring auxin) to rice
seedlings induced LR formation. The effect is specific for NO because the NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-
oxide (cPTIO) blocked the action of SNP and IBA. Endogenous NO was detected by the specific fluorescence probe 4-amino-5-methylamino-2′,7′-difluorofluorescein
diacetate. SNP- and IBA-induced NO fluorescence was specifically suppressed by cPTIO. Nitrate reductase (NR) inhibitor sodium
tungstate completely inhibited IBA-induced LR formation and NO fluorescence. However, nitric oxide synthase inhibitor N
G-nitro-l-arginine methyl ester hydrochloride slightly reduced IBA-induced LR formation and NO generation. It appears that NO generation
that occurs in response to IBA might primarily involve NR activity. Moreover, NO production caused by SNP and IBA was localized
in root area corresponding to LR emergence. The effects of Ca2+ chelators, Ca2+-channel inhibitors, and calmodulin antagonists on LR formation induced by SNP and IBA were also examined. All these inhibitors
were effective in reducing the action of SNP and IBA. However, Ca2+ chelators and Ca2+-channel inhibitors had no effect on SNP- and IBA-induced NO generation. It is concluded that cytosolic levels of Ca2+ may regulate SNP and IBA action through calmodulin-dependent mechanism. 相似文献
997.
The fluo family of indicators is frequently used in studying Ca(2+) physiology; however, choosing which fluo indicator to use is not obvious. Indicator properties are typically determined in well-defined aqueous solutions. Inside cells, however, the properties can change markedly. We have characterized each of three fluo variants (fluo-2MA, fluo-3 and fluo-4) in two forms-the acetoxymethyl (AM) ester and the K(+) salt. We loaded indicators into rat ventricular myocytes and used confocal microscopy to monitor depolarization-induced fluorescence changes and fractional shortening. Myocytes loaded with the indicator AM esters showed significantly different Ca(2+) transients and fractional shortening kinetics. Loading the K(+) salts via whole-cell patch-pipette eliminated differences between fluo-3 and fluo-4, but not fluo-2MA. Cells loaded with different indicator AM esters showed different staining patterns-suggesting differential loading into organelles. Ca(2+) dissociation constants (K(d,Ca)), measured in protein-rich buffers mimicking the cytosol were significantly higher than values determined in simple buffers. This increase in K(d,Ca) (decrease in Ca(2+) affinity) was greatest for fluo-3 and fluo-4, and least for fluo-2MA. We conclude that the structurally-similar fluo variants differ with respect to cellular loading, subcellular compartmentalization, and intracellular Ca(2+) affinity. Therefore, judicious choice of fluo indicator and loading procedure is advisable when designing experiments. 相似文献
998.
Hydrogen peroxide (H2O2) is considered a signal molecule inducing cellular stress. Both heat shock (HS) and Cd can increase H2O2 content. We investigated the involvement of H2O2 in HS- and Cd-mediated changes in the expression of ascorbate peroxidase (APX) and glutathione reductase (GR) in leaves of rice seedlings. HS treatment increased the content of H2O2 before it increased activities of APX and GR in rice leaves. Moreover, HS-induced H2O2 production and APX and GR activities could be counteracted by the NADPH oxidase inhibitors dipehenylene iodonium (DPI) and imidazole (IMD). HS-induced OsAPX2 gene expression was associated with HS-induced APX activity but was not regulated by H2O2. Cd-increased H2O2 content and APX and GR activities were lower with than without HS. Cd did not increase the expression of OsAPX and OsGR without HS treatment. Cd increased H2O2 content by Cd before it increased APX and GR activities without HS. Treatment with DPI and IMD effectively inhibited Cd-induced H2O2 production and APX and GR activities. Moreover, the effects of DPI and IMD could be rescued with H2O2 treatment. H2O2 may be involved in the regulation of HS- and Cd-increased APX and GR activities in leaves of rice seedlings. 相似文献
999.
Liu H Zhang J Liu CY Hayashi Y Kao WW 《Journal of cellular and molecular medicine》2012,16(5):1114-1124
It remains elusive as to what bone marrow (BM) cell types infiltrate into injured and/or diseased tissues and subsequently differentiate to assume the phenotype of residential cells, for example, neurons, cardiac myocytes, keratocytes, etc., to repair damaged tissue. Here, we examined the possibility of whether BM cell invasion via circulation into uninjured and injured corneas could assume a keratocyte phenotype, using chimeric mice generated by transplantation of enhanced green fluorescent protein (EGFP)(+) BM cells into keratocan null (Kera(-/-)) and lumican null (Lum(-/-)) mice. EGFP(+) BM cells assumed dendritic cell morphology, but failed to synthesize corneal-specific keratan sulfate proteoglycans, that is KS-lumican and KS-keratocan. In contrast, some EGFP(+) BM cells introduced by intrastromal transplantation assumed keratocyte phenotypes. Furthermore, BM cells were isolated from Kera-Cre/ZEG mice, a double transgenic mouse line in which cells expressing keratocan become EGFP(+) due to the synthesis of Cre driven by keratocan promoter. Three days after corneal and conjunctival transplantations of such BM cells into Kera(-/-) mice, green keratocan positive cells were found in the cornea, but not in conjunctiva. It is worthy to note that transplanted BM cells were rejected in 4 weeks. MSC isolated from BM were used to examine if BM mesenchymal stem cells (BM-MSC) could assume keratocyte phenotype. When BM-MSC were intrastromal-transplanted into Kera(-/-) mice, they survived in the cornea without any immune and inflammatory responses and expressed keratocan in Kera(-/-) mice. These observations suggest that corneal intrastromal transplantation of BM-MSC may be an effective treatment regimen for corneal diseases involving dysfunction of keratocytes. 相似文献
1000.
ABSTRACT: BACKGROUND: Promyelocytic leukemia protein (PML) is a tumor suppressor that is highly expressed in endothelial cells nonetheless its role in endothelial cell biology remains elusive. Tumor necrosis factor alpha TNF-a is an important cytokine associated with many inflammation-related diseases. We have previously demonstrated that TNF-a induces PML protein accumulation. We hypothesized that PML may play a role in TNF-a signaling pathway. To identify potential PML target genes and investigate the putative crosstalk between PML's function and TNF-a signaling in endothelial cells, we carried out a microarray analysis in human primary umbilical endothelial cells (HUVECs). RESULTS: We found that PML and TNF-a regulate common and distinct genes involved in a similar spectrum of biological processes, pathways and human diseases. More importantly, we found that PML is required for fine-tuning of TNF-a-mediated immune and inflammatory responses. Furthermore, our data suggest that PML and TNF-a synergistically regulate cell adhesion by engaging multiple molecular mechanisms. Our biological functional assays exemplified that adhesion of U937 human leukocytes to HUVECs is co-regulated by PML and TNF-a signaling. CONCLUSIONS: Together, our study identified PML as an essential regulator of TNF-a signaling by revealing the crosstalk between PML knockdown-mediated effects and TNF-a-elicited signaling, thereby providing novel insights into TNF-a signaling in endothelial cells. 相似文献