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The RecQ helicase is required by the RecF recombination pathway that is operative in recBC(D) sbcB sbcC(D) mutants of Escherichia coli. Genetic data suggest that RecQ participates in resection of DNA ends during initiation of recombination. In vitro, RecQ can unwind a variety of DNA substrates, including recombination intermediates such as D-loops and Holliday junctions. However, its potential role in processing of recombination intermediates during the late stage of the RecF pathway has not been genetically tested. Here we studied the effect of a recQ mutation on transductional recombination and DNA repair after γ-irradiation in ΔrecBCD ΔsbcB sbcC strains deficient for RuvABC, RecG and XerC proteins. RuvABC and RecG proteins process recombination intermediates in the late stage of recombination, whereas XerC is required to resolve chromosome dimers formed upon recombination. Our results do not reveal any substantial synergistic effect between the recQ mutation, on one hand, and ruvABC, recG and xerC mutations on the other. In addition, the recQ mutation suppresses chromosome segregation defects in γ-irradiated ruvABC recG and xerC mutants. These results suggest that RecQ acts upstream of RuvABC, RecG and XerC proteins, a finding that is compatible with its primary role in initiation of the RecF recombination pathway. 相似文献
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Jelena Juloski Maja Dimitrijevic Jovana Juloski Ivana Radovic 《Dental traumatology》2020,36(5):551-555
During extraction of the primary mandibular right second molar in an 11‐year‐old girl, the unerupted second premolar was accidentally extracted. Clinical and radiographic examination showed that the immediately replanted immature premolar was not oriented and positioned correctly. Four hours later, treatment consisted of manual extrusion of the permanent tooth bud, rotation, and gentle repositioning into its original position. Adequate replantation was confirmed by a post‐operative radiograph. After 2 years and 4 months, clinical examination revealed normal, healthy appearance of the replanted tooth, no sensitivity to percussion, no tenderness to palpation, and a slight response to a cold pulp sensibility test. A radiograph showed completely developed root with closed apical foramen, slightly irregular root morphology and shorter root length, complete obliteration of the pulp, and no signs of periapical pathosis. 相似文献
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Sander C. J. Verfaillie Sofie M. Adriaanse Maja A. A. Binnewijzend Marije R. Benedictus Rik Ossenkoppele Mike P. Wattjes Yolande A. L. Pijnenburg Wiesje M. van der Flier Adriaan A. Lammertsma Joost P. A. Kuijer Ronald Boellaard Philip Scheltens Bart N. M. van Berckel Frederik Barkhof 《European radiology》2015,25(10):3050-3059
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Domagoj Vra?i? Zoran Miovski Maja Strozzi Ivan Puhar Ana Badovinac Darko Bo?i? Darije Plan?ak 《Acta stomatologica Croatica》2015,49(1):14-20
Purpose
The aim of this research was to investigate the association of chronic and aggressive periodontitis with the severity of coronary artery disease which was angiographically verified.Material and methods
Subjects were selected among the hospitalized patients at the University Hospital Centre Zagreb who had coronary angiography done because of the chest pain. Thorough clinical examination included periodontal indices and clinical and socio-demographic characteristics of participants. Subjects were divided in two test groups, acute coronary syndrome (ACS) and stable coronary artery disease (CAD), and the control group with no significant CAD. Data were analyzed using Kruskal-Wallis and Pearson’s Chi-Square test.Results
From 106 subjects, 66 (62.3%) were hospitalized for ACS, 22 (20.7%) had stable CAD and only 18 (17.0%) had no significant CAD. Only 26 (24.5%) out of 106 patients were never smokers (p<0.05). Chronic periodontitis was the most common finding with 68.2% in ACS group and 54.5% in stable CAD group, while healthy patients without periodontitis (72.6%) were dominant in the control group (p<0.001). Stable CAD group had the highest mean probing depth (PD) 3.92±1.16, gingival recession (GR) 1.34±0.78, clinical attachment level (CAL) 4.60±1.41 and bleeding on probing (BOP) 45.98±26.19 values, whereas ACS group had mean PD value of 3.77±0.91, GR 1.11±0.66, CAL 4.32±1.08 and BOP 41.30±22.09, and no significant CAD group had mean PD value of 3.27±0.97, GR 0.69±0.37, CAL 3.62±1.04 and BOP 26.39±13.92 (p<0.05).Conclusion
Periodontitis was shown to be associated with angiographically verified coronary artery disease. Physical inactivity, poor oral hygiene and periodontal inflammation were observed in patients with ACS and stable CAD.Key words: Periodontitis, Periodontal Index, Cardiovascular Diseases, Coronary Artery Disease, Coronary Angiography 相似文献37.
Maja Šešelj Dana L. Duren Richard J. Sherwood 《Anatomical record (Hoboken, N.J. : 2007)》2015,298(9):1535-1547
Quantifying normal variation and the genetic underpinnings of anatomical structures is one of the main goals of modern morphological studies. However, the extent of genetic contributions to normal variation in craniofacial morphology in humans is still unclear. The current study addresses this gap by investigating the genetic underpinnings of normal craniofacial morphology. The sample under investigation consists of 75 linear and angular measurements spanning the entire craniofacial complex, recorded from lateral cephalographs of 1,379 participants in the Fels Longitudinal Study. Heritabilities for each trait were estimated using SOLAR, a maximum‐likelihood variance components approach utilizing all pedigree information for parameter estimation. Trait means and mean effects of the covariates age, sex, age2, sex × age, and sex × age2 were simultaneously estimated in the analytic models. All traits of the craniofacial complex were significantly heritable. Heritability estimates ranged from 0.10 to 0.60, with the majority being moderate. It is important to note that we found similar ranges of heritability occurring across the different functional/developmental components of the craniofacial complex, the splanchnocranium, the basicranium, and the neurocranium. This suggests that traits from different regions of the craniofacial complex are of comparable utility for the purposes of population history and phylogeny reconstruction. At the same time, this genetic influence on craniofacial morphology signals a caution to researchers of nongenetic studies to consider the implications of this finding when selecting samples for study given their project design and goals. Anat Rec, 298:1535–1547, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
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Per Damkier Dorte Lassen Mette Marie Hougaard Christensen Kenneth Grnkjr Madsen Maja Hellfritzsch Anton Pottegrd 《Basic & clinical pharmacology & toxicology》2019,124(1):28-31
Delta‐9‐tetrahydrocannabinol (THC), the main psychoactive cannabinoid in cannabis, may inhibit the cytochrome P450 enzyme CYP2C9. Consequently, cannabis use might infer a risk of drug‐drug interaction with substrates for this enzyme, which includes drugs known to have a narrow therapeutic window. In this study, we describe a case report of a 27‐year‐old man treated with warfarin due to mechanical heart valve replacement who presented with elevated international normalized ratio (INR) value (INR = 4.6) following recreational cannabis use. We conducted a review of the available literature, using the PubMed and EMBASE databases while following PRISMA guidelines. Following screening of 85 articles, three eligible articles were identified, including one in vitro study and two case reports. The in vitro study indicated that THC inhibits the CYP2C9‐mediated metabolism of warfarin. One case study reported of a man who on two occasions of increased marijuana use experienced INR values above 10 as well as bleeding. The other case study reported of a patient who initiated treatment with a liquid formulation of cannabidiol for the management of epilepsy, ultimately necessitating a 30% reduction in warfarin dose to maintain therapeutic INR values. The available, although sparse, data suggest that use of cannabinoids increases INR values in patients receiving warfarin. Until further data are available, we suggest patients receiving warfarin be warned against cannabis use. 相似文献
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