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991.
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Everaerts W Zhen X Ghosh D Vriens J Gevaert T Gilbert JP Hayward NJ McNamara CR Xue F Moran MM Strassmaier T Uykal E Owsianik G Vennekens R De Ridder D Nilius B Fanger CM Voets T 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(44):19084-19089
Reduced functional bladder capacity and concomitant increased micturition frequency (pollakisuria) are common lower urinary tract symptoms associated with conditions such as cystitis, prostatic hyperplasia, neurological disease, and overactive bladder syndrome. These symptoms can profoundly affect the quality of life of afflicted individuals, but available pharmacological treatments are often unsatisfactory. Recent work has demonstrated that the cation channel TRPV4 is highly expressed in urothelial cells and plays a role in sensing the normal filling state of the bladder. In this article, we show that the development of cystitis-induced bladder dysfunction is strongly impaired in Trpv4(-/-) mice. Moreover, we describe HC-067047, a previously uncharacterized, potent, and selective TRPV4 antagonist that increases functional bladder capacity and reduces micturition frequency in WT mice and rats with cystitis. HC-067047 did not affect bladder function in Trpv4(-/-) mice, demonstrating that its in vivo effects are on target. These results indicate that TRPV4 antagonists may provide a promising means of treating bladder dysfunction. 相似文献
994.
Fanny Lemée Valérie Bergoglio Anne Fernandez-Vidal Alice Machado-Silva Marie-Jeanne Pillaire Anne Bieth Catherine Gentil Lee Baker Anne-Laure Martin Claire Leduc Elena Lam Eddy Magdeleine Thomas Filleron Na?ma Oumouhou Bernd Kaina Mineaki Seki Fanny Grimal Magali Lacroix-Triki Alastair Thompson Henri Roché Jean-Christophe Bourdon Richard D. Wood Jean-Sébastien Hoffmann Christophe Cazaux 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(30):13390-13395
“Replicative stress” is one of the main factors underlying neoplasia from its early stages. Genes involved in DNA synthesis may therefore represent an underexplored source of potential prognostic markers for cancer. To this aim, we generated gene expression profiles from two independent cohorts (France, n = 206; United Kingdom, n = 117) of patients with previously untreated primary breast cancers. We report here that among the 13 human nuclear DNA polymerase genes, DNA Polymerase θ (POLQ) is the only one significantly up-regulated in breast cancer compared with normal breast tissues. Importantly, POLQ up-regulation significantly correlates with poor clinical outcome (4.3-fold increased risk of death in patients with high POLQ expression), and this correlation is independent of Cyclin E expression or the number of positive nodes, which are currently considered as markers for poor outcome. POLQ expression provides thus an additional indicator for the survival outcome of patients with high Cyclin E tumor expression or high number of positive lymph nodes. Furthermore, to decipher the molecular consequences of POLQ up-regulation in breast cancer, we generated human MRC5-SV cell lines that stably overexpress POLQ. Strong POLQ expression was directly associated with defective DNA replication fork progression and chromosomal damage. Therefore, POLQ overexpression may be a promising genetic instability and prognostic marker for breast cancer. 相似文献
995.
996.
Boleslaw Marczynski Beate Pesch Michael Wilhelm Bernd Rossbach Ralf Preuss Jens-Uwe Hahn Sylvia Rabstein Monika Raulf-Heimsoth Albrecht Seidel Hans-Peter Rihs Ansgar Adams Michael Scherenberg Anja Erkes Beate Engelhardt Kurt Straif Heiko Udo Käfferlein Jürgen Angerer Thomas Brüning 《Archives of toxicology》2009,83(10):947-957
Exposure to polycyclic aromatic hydrocarbons (PAH) and DNA damage were analyzed in coke oven (n = 37), refractory (n = 96), graphite electrode (n = 26), and converter workers (n = 12), whereas construction workers (n = 48) served as referents. PAH exposure was assessed by personal air sampling during shift and biological monitoring in urine post shift (1-hydroxypyrene, 1-OHP and 1-, 2 + 9-, 3-, 4-hydroxyphenanthrenes, ΣOHPHE). DNA damage was measured by 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodGuo) and DNA strand breaks in blood post shift. Median 1-OHP and ΣOHPHE were highest in converter workers (13.5 and 37.2 μg/g crea). The industrial setting contributed to the metabolite concentrations rather than the air-borne concentration alone. Other routes of uptake, probably dermal, influenced associations between air-borne concentrations and levels of PAH metabolites in urine making biomonitoring results preferred parameters to assess exposure to PAH. DNA damage in terms of 8-oxo-dGuo and DNA strand breaks was higher in exposed workers compared to referents ranking highest for graphite-electrode production. The type of industry contributed to genotoxic DNA damage and DNA damage was not unequivocally associated to PAH on the individual level most likely due to potential contributions of co-exposures. 相似文献
997.
Angelika Langsch Shibashish Giri Ali Acikgöz Inka Jasmund Bernd Frericks Augustinus Bader 《Toxicology letters》2009
Interspecies difference is an important issue in toxicology research. We compared the potential in vitro metabolism of human, porcine and rat hepatocytes over 2 weeks in culture in an organotypical culture model which reflects the in vivo situation. All three species show similar LDH-rates. Albumin measurements showed that rat cells are about twice as active as human and porcine hepatocytes. The ethoxyresorufin-O-deethylase (EROD) activity of the rat hepatocytes is with about 14 μU/106 cells distinctly higher than those of porcine and human cells (1.8 and 0.5 μU/106 cells respectively), furthermore, the activity of the rat EROD increases slightly during the prolonged time in culture, whereas those of porcine and human enzymes slightly decrease. Concerning ethoxycoumarin-O-deethylase (ECOD), the enzyme activities are found to be in three different ranges where rat cells show the highest activity with 66 μU/106 cells, porcine hepatocytes exhibit an activity of about 23 μU/106 cells, and human activity is lowest with 0.7 μU/106 cells. All three species show a similar decreasing trend of ECOD during the period of study. Regarding the biotransformation of testosterone, human and porcine liver cells form three major metabolites whereas rat cells form a mixture of all measured metabolites. Hence, in vitro metabolism using porcine hepatocytes would be much more scientific sense than one using rat hepatocytes since the metabolic pathways are much closer to human metabolism. 相似文献
998.
Löwe B Decker O Müller S Brähler E Schellberg D Herzog W Herzberg PY 《Medical care》2008,46(3):266-274
BACKGROUND: The 7-item Generalized Anxiety Disorder Scale (GAD-7) is a practical self-report anxiety questionnaire that proved valid in primary care. However, the GAD-7 was not yet validated in the general population and thus far, normative data are not available. OBJECTIVES: To investigate reliability, construct validity, and factorial validity of the GAD-7 in the general population and to generate normative data. RESEARCH DESIGN: Nationally representative face-to-face household survey conducted in Germany between May 5 and June 8, 2006. SUBJECTS: Five thousand thirty subjects (53.6% female) with a mean age (SD) of 48.4 (18.0) years. MEASURES: The survey questionnaire included the GAD-7, the 2-item depression module from the Patient Health Questionnaire (PHQ-2), the Rosenberg Self-Esteem Scale, and demographic characteristics. RESULTS: Confirmatory factor analyses substantiated the 1-dimensional structure of the GAD-7 and its factorial invariance for gender and age. Internal consistency was identical across all subgroups (alpha = 0.89). Intercorrelations with the PHQ-2 and the Rosenberg Self-Esteem Scale were r = 0.64 (P < 0.001) and r = -0.43 (P < 0.001), respectively. As expected, women had significantly higher mean (SD) GAD-7 anxiety scores compared with men [3.2 (3.5) vs. 2.7 (3.2); P < 0.001]. Normative data for the GAD-7 were generated for both genders and different age levels. Approximately 5% of subjects had GAD-7 scores of 10 or greater, and 1% had GAD-7 scores of 15 or greater. CONCLUSIONS: Evidence supports reliability and validity of the GAD-7 as a measure of anxiety in the general population. The normative data provided in this study can be used to compare a subject's GAD-7 score with those determined from a general population reference group. 相似文献
999.
Snyder-Ramos SA Möhnle P Weng YS Böttiger BW Kulier A Levin J Mangano DT;Investigators of the Multicenter Study of Perioperative Ischemia;MCSPI Research Group 《Transfusion》2008,48(7):1284-1299
BACKGROUND: Although blood utilization has been under considerable scrutiny for the past two decades, particularly for surgery, studies comparing perioperative blood transfusion practices between countries are rare, and the evolution of international standards remains unknown. Therefore, the objective of this evaluation was to compare the perioperative transfusion of blood components in cardiac surgery in multiple centers in different countries. STUDY DESIGN AND METHODS: Transfusion practice was investigated prospectively in 70 centers among 16 countries. A total of 5065 randomly selected cardiac surgery patients of the Multicenter Study of Perioperative Ischemia Epidemiology II (EPI II) Study were evaluated. Utilization of red blood cells (RBCs), fresh-frozen plasma (FFP), and platelets (PLTs) was assessed daily, before, during, and after surgery until hospital discharge. RESULTS: Intraoperative RBC transfusion varied from 9 to 100 percent among the 16 countries, and 25 to 87 percent postoperatively (percentage of transfused patients). Similarly, frequency of transfusion of FFP varied from 0 to 98 percent intraoperatively and 3 to 95 percent postoperatively, and PLT transfusion from 0 to 51 and 0 to 39 percent, respectively. Moreover, there were not only marked differences in transfusion rates between centers in different countries but also in interinstitutional comparison of multiple centers within countries. CONCLUSION: In cardiac surgical patients, marked variability in transfusion practice exists between centers in various countries and suggests differences in perioperative practice patterns as well as possible inappropriate use. International standardization of perioperative practice patterns as well as transfusion regimes appears necessary. 相似文献
1000.