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171.
172.
Szular J Sehadova H Gentile C Szabo G Chou WH Britt SG Stanewsky R 《Journal of biological rhythms》2012,27(1):25-36
Circadian clocks of most organisms are synchronized with the 24-hour solar day by the changes of light and dark. In Drosophila, both the visual photoreceptors in the compound eyes as well as the blue-light photoreceptor Cryptochrome expressed within the brain clock neurons contribute to this clock synchronization. A specialized photoreceptive structure located between the retina and the optic lobes, the Hofbauer-Buchner (H-B) eyelet, projects to the clock neurons in the brain and also participates in light synchronization. The compound eye photoreceptors and the H-B eyelet contain Rhodopsin photopigments, which activate the canonical invertebrate phototransduction cascade after being excited by light. We show here that 2 of the photopigments present in these photoreceptors, Rhodopsin 5 (Rh5) and Rhodopsin 6 (Rh6), contribute to light synchronization in a mutant (norpA(P41) ) that disrupts canonical phototransduction due to the absence of Phospholipase C-β (PLC-β). We reveal that norpA(P41) is a true loss-of-function allele, resulting in a truncated PLC-β protein that lacks the catalytic domain. Light reception mediated by Rh5 and Rh6 must therefore utilize either a different (nonretinal) PLC-β enzyme or alternative signaling mechanisms, at least in terms of clock-relevant photoreception. This novel signaling mode may distinguish Rhodopsin-mediated irradiance detection from image-forming vision in Drosophila. 相似文献
173.
Fazlić H Brborović O Rukavina TV Fister K Milosević M Mustajbegović J 《Collegium antropologicum》2012,36(Z1):165-169
This study aimed to assess levels of stress in Croatian adult population using PSS, in a population study (Croatian Adult Cohort Health Study - CroHort). Our results show that the levels of stress were 17.46 (SD = 6.73) for men and 18.32 (SD = 6.46) for women in Croatia. The lowest levels of stress experienced men living in urban area while women living in rural area had the highest level. Men and women who had university degree had significantly lower level of stress. The lowest levels of stress experienced participants who had much better financial condition than average. In men, stress was associated to weak heart, lower back pain, poor financial condition of the household and high alcohol consumption. In women, stress was associated to poor mental health, poor social functioning, poorer financial condition of the household, higher age, lower education, low monthly income of the household and poor general health. 相似文献
174.
Bremmer SC Hall H Martinez JS Eissler CL Hinrichsen TH Rossie S Parker LL Hall MC Charbonneau H 《The Journal of biological chemistry》2012,287(3):1662-1669
Mitotic cell division is controlled by cyclin-dependent kinases (Cdks), which phosphorylate hundreds of protein substrates responsible for executing the division program. Cdk inactivation and reversal of Cdk-catalyzed phosphorylation are universal requirements for completing and exiting mitosis and resetting the cell cycle machinery. Mechanisms that define the timing and order of Cdk substrate dephosphorylation remain poorly understood. Cdc14 phosphatases have been implicated in Cdk inactivation and are thought to be generally specific for Cdk-type phosphorylation sites. We show that budding yeast Cdc14 possesses a strong and unusual preference for phosphoserine over phosphothreonine at Pro-directed sites in vitro. Using serine to threonine substitutions in the Cdk consensus sites of the Cdc14 substrate Acm1, we demonstrate that phosphoserine specificity exists in vivo. Furthermore, it appears to be a conserved property of all Cdc14 family phosphatases. An invariant active site residue was identified that sterically restricts phosphothreonine binding and is largely responsible for phosphoserine selectivity. Optimal Cdc14 substrates also possessed a basic residue at the +3 position relative to the phosphoserine, whereas substrates lacking this basic residue were not effectively hydrolyzed. The intrinsic selectivity of Cdc14 may help establish the order of Cdk substrate dephosphorylation during mitotic exit and contribute to roles in other cellular processes. 相似文献
175.
Itoh S Saito T Hirata M Ushita M Ikeda T Woodgett JR Algül H Schmid RM Chung UI Kawaguchi H 《The Journal of biological chemistry》2012,287(35):29227-29236
176.
177.
Verma N Dimitrova M Carter DM Crevar CJ Ross TM Golding H Khurana S 《Journal of virology》2012,86(10):5515-5522
The H1N1 2009 influenza virus (H1N1pdm09) pandemic had several unexpected features, including low morbidity and mortality in older populations. We performed in-depth evaluation of antibody responses generated following H1N1pdm09 infection of naïve ferrets and of 130 humans ranging from the very young (0 to 9 years old) to the very old (70 to 89 years old). In addition to hemagglutination inhibition (HI) titers, we used H1N1pdm09 whole-genome-fragment phage display libraries (GFPDL) to evaluate the antibody repertoires against internal genes, hemagglutinin (HA), and neuraminidase (NA) and also measured antibody affinity for antigenic domains within HA. GFPDL analyses of H1N1pdm09-infected ferrets demonstrated gradual development of antibody repertoires with a focus on M1 and HA1 by day 21 postinfection. In humans, H1N1pdm09 infection in the elderly (>70 years old) induced antibodies with broader epitope recognition in both the internal genes and the HA1 receptor binding domain (RBD) than for the younger age groups (0 to 69 years). Importantly, post-H1N1 infection serum antibodies from the elderly demonstrated substantially higher avidity for recombinant HA1 (rHA1) (but not HA2) than those from younger subjects (50% versus <22% 7 M urea resistance, respectively) and lower antibody dissociation rates using surface plasmon resonance. This is the first study in humans that provides evidence for a qualitatively superior antibody response in the elderly following H1N1pdm09 infection, indicative of recall of long-term memory B cells or long-lived plasma cells. These findings may help explain the age-related morbidity and mortality pattern observed during the H1N1pdm09 pandemic. 相似文献
178.
Parajuli RP Fujiwara T Umezaki M Furusawa H Ser PH Watanabe C 《Biological trace element research》2012,147(1-3):75-83
The purpose of this study is to evaluate the cord blood level of toxic and trace elements and to identify their determinants in Terai, Nepal. One hundred pregnant women were recruited from one hospital in Chitwan, Nepal in 2008. The cord blood levels of toxic [lead (Pb), arsenic (As), and cadmium (Cd)], essential trace elements [zinc (Zn), selenium (Se), and copper (Cu)], demographic, socioeconomic, and behavioral variables were measured. The mean values of Pb, As, Cd, Zn, Se, and Cu in cord blood level were found as 31.7, 1.46, 0.39, 2,286, 175, and 667 μg/L, respectively. In the multivariate regression model, cord blood As levels from less educated mothers were higher than those from educated mothers (coefficient = -0.01, 95% confidence interval [CI] = -0.02-0.00). The maternal age was positively associated with the cord blood Cd level (coefficient = 0.02, 95% CI = 0.01-0.03), while it was negatively associated with the cord blood As level (coefficient = -0.01, 95% CI = -0.03--0.01). Cord blood levels of Pb, Zn, Se, and Cu were not associated with maternal age, socioeconomic status, living environment, and smoking status. As and Cd levels were relatively lower than those reported in previous studies in Asia, while the levels of Pb and the trace elements were similar. Less educated mothers are more likely to become a higher in utero As source to their fetus, and fetuses of older mothers were more likely to have higher in utero Cd exposure in Terai, Nepal. 相似文献
179.
Rasova K Dolezil D Kalistova H Kucera P Juzova O Zimova D Medova E Jandova D Tintera J Ibrahim I Zvara K Bicikova M Martinkova P 《Neuro endocrinology letters》2012,33(1):67-75
OBJECTIVES: The aim of this study was to confirm the immunoregulatory and anti-inflammatory changes in the immunologic profile after two months of the facilitation physiotherapy in patients with multiple sclerosis; and to determine whether the changes in the immunologic profile correlate with the changes in dehydroepiandrosterone, the brain microstructure and clinical functions. Design & Setting: A group of 12 patients with multiple sclerosis was examined twice: at the beginning and 2 months later after the patients had undergone the facilitation therapy. Standardized tests evaluating chosen clinical functions (balance, righting, equilibrium and protective reactions, tremor, dysdiadochokinesis, dysmetry, fine hand function and walking), immune parameters (parameters of the humoral and cellular immunity), dehydroepiandrosterone and diffusion tensor imaging (the fractional anisotropy, mean diffusivity) were measured. The patients underwent the facilitation physiotherapy in two sessions lasting two hours each week for two months. Results: All clinical and diffusion tensor imaging parameters significantly improved following the therapy. Without the correction for multiple comparisons, there were significant changes in the IgG, IgG1 subclasses, in the numbers of Neutrophils and Lymphocytes, the T cells (CD3+) absolute number, the T cytotoxic subpopulation (CD3+CD8+) absolute number, B cells (CD19+) and the Natural killer cells. In addition, there was a significant correlation between the changes in the clinical functions and the changes in IgG1 (r=0.67), and between the changes in the mean diffusivity and the changes in CD3+CD8+ absolute (r=-0.61). The changes in the immune parameters and the mentioned correlations were not significant in view of the number of comparisons and thus necessitate further validation. No changes in the dehydroepiandrosterone concentration after the therapy were confirmed. Conclusion: The study suggests new possibilities of physiotherapy to influence the psycho-neuro-endocrine-immune response in patients with multiple sclerosis. 相似文献
180.
Oxime HI-6 is an efficient reactivator of the acetylcholinesterase inhibited by organophosphorous nerve agents. In this study we have estimated cytotoxicity of HI-6 by the colony forming assay and genotoxicity by the comet assay on human and rodent cell lines. IC50 of HI-6 assessed by the colony forming capacity was 3.59 mM for HeLa cells and 5.18 mM for a mouse cell line L929. Small difference in cytotoxicity was found among other cell lines tested: IC50 was 1.61 mM for human A549 cells, 1.14 mM for UROtse line, 1.96 mM and 1.71 mM for Chinese hamster cells AA8 and UV-20, respectively. The A549 cell viability measured with the MTT test was 5 times decreased comparing 2 and 24 hours of HI-6 oxime treatment. The 5 mM HI-6 concentration reduced the viability within 2 hours to 95% only, however, it induced a significant number of DNA breaks in mouse cells L929, and also in human UROtse and HepG2 cells. 1-β-D-arabinofuranosylcytosine (10(-4) M) and hydroxyurea (10(-2) M), supplemented to the cultivation medium, did not cause any significant accumulation of DNA breaks during treatment, which indicated that the nucleotide excision repair was not acting on the induced DNA damage. 相似文献