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1.
The chromatin assembly factor subunit FASCIATA1 is involved in homologous recombination in plants 总被引:9,自引:0,他引:9 下载免费PDF全文
DNA replication in cycling eukaryotic cells necessitates the reestablishment of chromatin after nucleosome redistribution from the parental to the two daughter DNA strands. Chromatin assembly factor 1 (CAF-1), a heterotrimeric complex consisting of three subunits (p150/p60/p48), is one of the replication-coupled assembly factors involved in the reconstitution of S-phase chromatin. CAF-1 is required in vitro for nucleosome assembly onto newly replicated chromatin in human cells and Arabidopsis thaliana, and defects in yeast (Saccharomyces cerevisiae) affect DNA damage repair processes, predominantly those involved in genome stability. However, in vivo chromatin defects of caf-1 mutants in higher eukaryotes are poorly characterized. Here, we show that fasciata1-4 (fas1-4), a new allele of the Arabidopsis fas1 mutant defective in the p150 subunit of CAF-1, has a severe developmental phenotype, reduced heterochromatin content, and a more open conformation of euchromatin. Most importantly, homologous recombination (HR), a process involved in maintaining genome stability, is increased dramatically in fas1-4, as indicated by a 96-fold stimulation of intrachromosomal HR. Together with the open conformation of chromatin and the nearly normal expression levels of HR genes in the mutant, this result suggests that chromatin is a major factor restricting HR in plants. 相似文献
2.
Edelgard Nowack 《Human genetics》1965,1(6):516-536
Ohne ZusammenfassungMit 11 TextabbildungenDiese Arbeit wurde der Medizinischen Fakultät der Universität Hamburg als Dissertation zur Erlangung des Grades eines Doktors der Medizin vorgelegt. Die zugrundeliegenden Untersuchungen wurden mit Unterstützung durch die Deutsche Forschungsgemeinschaft durchgeführt. 相似文献
3.
Marc Schindewolf Svantje Schwaner Manfred Wolter Hartmut Kroll Andreas Recke Roland Kaufmann Wolf-Henning Boehncke Edelgard Lindhoff-Last Ralf J. Ludwig 《CMAJ》2009,181(8):477-481
Background
Little is known about the incidence and causes of heparin-induced skin lesions. The 2 most commonly reported causes of heparin-induced skin lesions are immune-mediated heparin-induced thrombocytopenia and delayed-type hypersensitivity reactions.Methods
We prospectively examined consecutive patients who received subcutaneous heparin (most often enoxaparin or nadroparin) for the presence of heparin-induced skin lesions. If such lesions were identified, we performed a skin biopsy, platelet count measurements, and antiplatelet-factor 4 antibody and allergy testing.Results
We enrolled 320 patients. In total, 24 patients (7.5%, 95% confidence interval [CI] 4.7%–10.6%) had heparin-induced skin lesions. Delayed-type hypersensitivity reactions were identified as the cause in all 24 patients. One patient with histopathologic evidence of delayed-type hypersensitivity tested positive for antiplatelet-factor 4 antibodies. We identified the following risk factors for heparin-induced skin lesions: a body mass index greater than 25 (odds ratio [OR] 4.6, 95% CI 1.7–15.3), duration of heparin therapy longer than 9 days (OR 5.9, 95% CI 1.9–26.3) and female sex (OR 3.0, 95% CI 1.1–8.8).Interpretation
Heparin-induced skin lesions are relatively common, have identifiable risk factors and are commonly caused by a delayed-type hypersensitivity reaction (type IV allergic response). (ClinicalTrials.gov trial register no. .)Hpeparin has been used as an anticoagulant for over 60 years. NCT005104321 Well-known adverse effects of heparin therapy are bleeding, osteoporosis, hair loss, and immune and nonimmune heparin-induced thrombocytopenia. The incidence of heparin-induced skin lesions is unknown, despite being increasingly reported.2–4 Heparin-induced skin lesions may be caused by at least 5 mechanisms: delayed-type (type IV) hypersensitivity responses,2,4–6 immune-mediated thrombocytopenia,3 type I allergic reactions,7,8 skin necrosis9 and pustulosis.10Heparin-induced skin lesions may indicate the presence of life-threatening heparin-induced thrombocytopenia11 — even in the absence of thrombocytopenia.3 There are no data available on the incidence of heparin-induced skin lesions or their causes. Given the rising number of reports of heparin-induced skin lesions and the importance of correctly diagnosing this condition, we sought to determine the incidence of heparin-induced skin lesions. 相似文献4.
C. Sorg J. Brüggen Edelgard Seibert E. Macher 《Cancer immunology, immunotherapy : CII》1978,3(4):259-271
Summary Established melanoma cell lines were cultured for one passage (approximately 1 week) in different lots of fetal calf and new born calf sera and then tested against a panel of previously positively reacting sera from melanoma patients and polyspecific HL-A alloantisera. Using indirect immunofluorescence the cells showed varying degrees of reactivity ranging from positive to negative reactions depending on the supplementing serum in the culture medium. When standardized culture conditions were used and the cells were tested by immune adherence at several weeks intervals against panels of sera from melanoma patients, from tumor patients other than melanoma, from pregnant women, and from normal donors, most of the sera reacted identical, but some sera not only had changed quantitatively but also qualitatively from a negative to a positive reaction and vice versa indicating a shift in the spectrum of expressed antigens. When single cell clones from a cell line were isolated and tested against a panel of antisera, striking differences in reactivity were observed suggesting that the shift in the spectrum of expressed antigens was due to the outgrowth of dominating subclones with antigen patterns different from the previously dominating subclones. This conclusion was further supported by experiments in which a weakly positive reacting serum was employed to separate a cell line into positively and negatively reacting sublines. Unit gravity sedimentation and density gradient sedimentation were used in order to separate rosetted from non-rosetted tumor cells which had been prepared by immune adherence. It is concluded that cultured cell lines are in a dynamic state and that differentiation is one of the major mechanisms accounting for a change in antigen expression. 相似文献
5.
Evidence derived from molecular studies in recent years has revealed that corticioid fungal genera are present in all major clades of Homobasidiomycetes. Brunneocorticium pyriforme, a corticioid fungus is proposed as a new species and placed in a new genus belonging to the euagarics clade. This fungus has been collected in subtropical-tropical Taiwan and southern Yunnan Province, China. Basidiocarps often occur on bark of living Murraya spp. (Rutaceae). Basidiocarps of B. pyriforme are resupinate with a smooth hymenial surface, a dimitic hyphal system, with nodose-septate generative hyphae and abundant yellowish brown skeletal hyphae, and leptocystidia. It has 2-sterigmate basidia and pear-shaped basidiospores. Phylogenetic analysis based on sequence data derived from LSU rDNA included Brunneocorticium in the euagarics clade of Homobasidiomycetes, allied to the agaricoid genera Marasmiellus, Campanella, etc. The molecular analysis indicated that the Brunneocorticium was independent from other corticioid genera with similar morphological features. 相似文献
6.
Hanna Leicht Hans-Helmut K?nig Nina Stuhldreher Cadja Bachmann Horst Bickel Angela Fuchs Kathrin Heser Frank Jessen Mirjam K?hler Melanie Luppa Edelgard M?sch Michael Pentzek Steffi Riedel-Heller Martin Scherer Jochen Werle Siegfried Weyerer Birgitt Wiese Wolfgang Maier for the AgeCoDe study group 《PloS one》2013,8(7)
Objective
To analyse predictors of costs in dementia from a societal perspective in a longitudinal setting.Method
Healthcare resource use and costs were assessed retrospectively using a questionnaire in four waves at 6-month intervals in a sample of dementia patients (N = 175). Sociodemographic data, dementia severity and comorbidity at baseline, cognitive impairment and impairment in basic and instrumental activities of daily living were also recorded. Linear mixed regression models with random intercepts for individuals were used to analyse predictors of total and sector-specific costs.Results
Impairment in activities of daily living significantly predicted total costs in dementia patients, with associations between basic activities of daily living and formal care costs on the one and instrumental activities of daily living and informal care costs on the other hand. Nursing home residence was associated with lower total costs than residence in the community. There was no effect of cognition on total or sector-specific costs.Conclusion
Cognitive deficits in dementia are associated with costs only via their effect on the patients'' capacity for activities of daily living. Transition into a nursing home may reduce total costs from a societal perspective, owing to the fact that a high amount of informal care required by severely demented patients prior to transition into a nursing home may cause higher costs than inpatient nursing care. 相似文献7.
Jessen F Wiese B Bickel H Eiffländer-Gorfer S Fuchs A Kaduszkiewicz H Köhler M Luck T Mösch E Pentzek M Riedel-Heller SG Wagner M Weyerer S Maier W van den Bussche H;AgeCoDe Study Group 《PloS one》2011,6(2):e16852
Background
Current approaches for AD prediction are based on biomarkers, which are however of restricted availability in primary care. AD prediction tools for primary care are therefore needed. We present a prediction score based on information that can be obtained in the primary care setting.Methodology/Principal Findings
We performed a longitudinal cohort study in 3.055 non-demented individuals above 75 years recruited via primary care chart registries (Study on Aging, Cognition and Dementia, AgeCoDe). After the baseline investigation we performed three follow-up investigations at 18 months intervals with incident dementia as the primary outcome.The best set of predictors was extracted from the baseline variables in one randomly selected half of the sample. This set included age, subjective memory impairment, performance on delayed verbal recall and verbal fluency, on the Mini-Mental-State-Examination, and on an instrumental activities of daily living scale. These variables were aggregated to a prediction score, which achieved a prediction accuracy of 0.84 for AD. The score was applied to the second half of the sample (test cohort). Here, the prediction accuracy was 0.79. With a cut-off of at least 80% sensitivity in the first cohort, 79.6% sensitivity, 66.4% specificity, 14.7% positive predictive value (PPV) and 97.8% negative predictive value of (NPV) for AD were achieved in the test cohort. At a cut-off for a high risk population (5% of individuals with the highest risk score in the first cohort) the PPV for AD was 39.1% (52% for any dementia) in the test cohort.Conclusions
The prediction score has useful prediction accuracy. It can define individuals (1) sensitively for low cost-low risk interventions, or (2) more specific and with increased PPV for measures of prevention with greater costs or risks. As it is independent of technical aids, it may be used within large scale prevention programs. 相似文献8.
F Bohmann A Mirceska J Pfeilschifter E Lindhoff-Last H Steinmetz C Foerch W Pfeilschifter 《PloS one》2012,7(7):e40804
Background
Dabigatran etexilate (DE) is a new oral direct thrombin inhibitor. Clinical trials point towards a favourable risk-to-benefit profile of DE compared to warfarin. In this study, we evaluated whether hemorrhagic transformation (HT) occurs after experimental stroke under DE treatment as we have shown for warfarin.Methods
44 male C57BL/6 mice were pretreated orally with 37.5 mg/kg DE, 75 mg/kg DE or saline and diluted thrombin time (dTT) and DE plasma concentrations were monitored. Ischemic stroke was induced by transient middle cerebral artery occlusion (tMCAO) for 1 h or 3 h. We assessed functional outcome and HT blood volume 24 h and 72 h after tMCAO.Results
After 1 h tMCAO, HT blood volume did not differ significantly between mice pretreated with DE 37.5 mg/kg and controls (1.5±0.5 µl vs. 1.8±0.5 µl, p>0.05). After 3 h tMCAO, DE-anticoagulated mice did also not show an increase in HT, neither at the dose of 37.5 mg/kg equivalent to anticoagulant treatment in the therapeutic range (1.3±0.9 µl vs. control 2.3±0.5 µl, p>0.05) nor at 75 mg/kg, clearly representing supratherapeutic anticoagulation (1.8±0.8 µl, p>0.05). Furthermore, no significant increase in HT under continued anticoagulation with DE 75 mg/kg could be found at 72 h after tMCAO for 1 h (1.7±0.9 µl vs. control 1.6±0.4 µl, p>0.05).Conclusion
Our experimental data suggest that DE does not significantly increase hemorrhagic transformation after transient focal cerebral ischemia in mice. From a translational viewpoint, this indicates that a continuation of DE anticoagulation in case of an ischemic stroke might be safe, but clearly, clinical data on this question are warranted. 相似文献9.
Freidenberg BM Blanchard EB Wulfert E Malta LS 《Applied psychophysiology and biofeedback》2002,27(4):251-260
Despite somewhat high attrition and relapse rates, cognitive–behavioral interventions for pathological gambling seem promising. As a possible remedy to these problems, we conducted a preliminary study of gambling-specific cognitive–behavior therapy (CBT) with the addition of motivational enhancement techniques (MET) for the treatment of pathological gamblers. Data on psychophysiological arousal upon exposure to imagined gambling vignettes were collected at both pre- and posttreatment. Results indicate that participants showed decreases in degree of arousal during the vignettes from pre- to posttreatment. There was also a strong dose–response relationship between reductions in gambling symptoms and reductions in arousal. These findings are discussed, as are their implications for further study of pathological gambling. 相似文献
10.
André Hajek Christian Brettschneider Carolin Lange Tina Posselt Birgitt Wiese Susanne Steinmann Siegfried Weyerer Jochen Werle Michael Pentzek Angela Fuchs Janine Stein Tobias Luck Horst Bickel Edelgard M?sch Michael Wagner Frank Jessen Wolfgang Maier Martin Scherer Steffi G. Riedel-Heller Hans-Helmut K?nig AgeCoDe Study Group 《PloS one》2015,10(12)