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1.
Benyam Kinde Harrison W. Gabel Caitlin S. Gilbert Eric C. Griffith Michael E. Greenberg 《Proceedings of the National Academy of Sciences of the United States of America》2015,112(22):6800-6806
DNA methylation at CpG dinucleotides is an important epigenetic regulator common to virtually all mammalian cell types, but recent evidence indicates that during early postnatal development neuronal genomes also accumulate uniquely high levels of two alternative forms of methylation, non-CpG methylation and hydroxymethylation. Here we discuss the distinct landscape of DNA methylation in neurons, how it is established, and how it might affect the binding and function of protein readers of DNA methylation. We review studies of one critical reader of DNA methylation in the brain, the Rett syndrome protein methyl CpG-binding protein 2 (MeCP2), and discuss how differential binding affinity of MeCP2 for non-CpG and hydroxymethylation may affect the function of this methyl-binding protein in the nervous system. 相似文献
2.
Hinrich Böhner Detlef Kindgen-Milles Andreas Grust Rolf Buhl Wolf-Christian Lillotte Barbara T. Müller Eckhard Müller Günter Fürst Wilhelm Sandmann 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2002,387(1):21-26
BACKGROUND: The efficacy of nasal continuous positive airway pressure (nCPAP) as a prophylactic method for preventing cardiopulmonary complications after major vascular surgery has not been investigated. PATIENTS/METHODS: In a prospective randomized trial, 204 patients undergoing elective midline laparotomy for vascular surgery were randomized to receive standard therapy ( n=105) or additional prophylactic nCPAP ( n=99) for the first postoperative night. Postoperative oxygenation, incidence of severe cardiac, and pulmonary complications, length of intensive care surveillance and length of total postoperative hospital stay (LOS) were compared. RESULTS: Prophylactic nCPAP significantly reduced the number of patients with severe oxygenation disturbances defined as paO(2) < 70 mmHg with FiO(2) > or = 0.7 (5 versus 17, P=.01). There were no differences with respect to death, cardiac and pulmonary complications, length of intensive care surveillance or LOS. CONCLUSION: Prophylactic 12 h nCPAP significantly reduces the occurrence of postoperative oxygenation disturbances but has no effect on cardiac or pulmonary complications, need for intensive care, LOS or mortality after major vascular surgery. 相似文献
3.
Fused Thiopyrones, III: Sulfones from Methyl 4,5-Dihydro-4-oxothiopyrano[3,2-b]indole-2-carboxylate and Methyl 4,9-Dihydro-4-oxothiopyrano[2,3-b]indole-2-carboxylate On treatment with m-chloroperbenzoic acid (mCPBA) the thiopyrones 1 and 4 are oxidized to the sulfones 2 and 5 , which add ethanol to yield the thiopyranosulfones 3 and 6 as mixtures of diastereomers. In one case a 3-hydroxy compound ( 7 ) could be isolated. 相似文献
4.
A convenience sample of hospital workers, those receiving influenza vaccine and those not receiving vaccine, were asked to complete questionnaires delineating the occurrence of symptoms (e.g., fever, headache, extreme tiredness, dry cough, sore throat, runny nose, stuffy nose, muscle aches) and absenteeism in the 7-day period post-vaccination if vaccinated. Those unvaccinated completed the questionnaire in a self-selected 7 consecutive day period during the study conducted from November 2004 to February 2005. Those receiving either Fluzone or FluMist reported significantly fewer symptoms and related absenteeism than the unvaccinated group (p < .05). Administration of influenza vaccine did not result in higher rates of post-vaccination symptoms as compared to an unvaccinated group. Further, vaccinated employees did not experience higher absenteeism rates as a result of receiving either influenza vaccine. However, for those reporting absenteeism as a result of symptoms, mean absenteeism days were highest in the FluMist group (4.5 days) compared to the unvaccinated group (2.1 days) and the Fluzone group (1.9 days). 相似文献
5.
6.
Twenty-four patients treated with 150 mg amitriptyline per day for an episode of major depression underwent a standardized heart rate analysis (HRA) before therapy and after 14 days. The battery of cardiovascular reflex tests included the determination of the coefficient of variation (CV) while resting and during deep respiration, a spectral analysis of heart rate, the heart rate response to standing, and the Valsalva manoeuvre. The results of the initial HRA did not differ from a group of 24 normal control subjects matched for age and sex. On day 14 of treatment the patients showed significantly reduced values of heart rate variability in all tests (P<0.0001), probably due to the anticholinergic side effects of amitriptyline. Heart rate increased form 78.1 to 93.6 bpm on average (P<0.0001). Abnormal CV at rest was registered in 96% of the patients; during deep respiration 29% showed abnormal CV results. An abnormal spectral analysis was found in 100% of the cases (low frequency peak: 42%, mid-frequency peak: 100%, high frequency peak: 79%). The heart rate response to standing was abnormal in 75% and the Valsalva test in 33% of the cases. Eighty-eight percent of the patients fulfilled the criteria of a cardiovascular autonomic neuropathy under the conditions of amitriptyline therapy. As yet, the consequences of these changes for the patients have not been sufficiently elucidated. 相似文献
7.
3-Alkoxy-1.2.3-oxathiazolidin-4-one-2-oxides and 1-Alkoxyindolin-2-ones from N-Alkoxyglycolamides and Thionyl Chloride or 1.1′-Thionyldiimidazole The reaction of N-alkoxyglycolamides 1 with thionyl chloride or 1.1′-thionyldiimidazole is shown to produce, dependending on the substituents at C-2 in 1 , either 3-alkoxy-1.2.3-oxathiazolidin-4-one-2-oxides 4 or 1-alkoxy-3-arylindolin-2-ones 6 . 相似文献
8.
Quantification of oxidative DNA modifications in mitochondria 总被引:2,自引:0,他引:2
Specific repair endonucleases were used to quantify oxidativemodifications in mitochondrial DNA (mtDNA) from rat liver andfrom porcine liver and kidney by means of a relaxation assay.In rat liver mitochondria the number of modifications sensitiveto formamidopyrimidine-DNA glycosylase (FPG protein), whichinclude 8-hydroxyguanine (8-oxo-7, 8-dihydro-guanine) residues,was only 0.8±0.2 per 105 base pairs (bp). Even lowervalues were observed in porcine kidney (0.5±0.3 per 105bp) and liver (0.4±0.2 per 105 bp). The numbers of sitesof base loss (AP sites) sensitive to T4 endonuclease V and of5,6-dihydropyrimidines sensitive to endonuclease III were lessthan 0.2 per 105 bp in all cases. The data provide evidencethat the steady-state levels of oxidative mtDNA modificationsare low under physiological conditions, either because reactiveoxygen species generated in the mitochondria are instantly inactivatedor because of efficient DNA repair processes inside mitochondria. 相似文献
9.
A greenstick intercondylar fracture of the distal humerus occurred in a 14-year-old boy. The minimal displacement and stability of the injury allowed early range of motion with healing in an anatomic position and restoration of the preinjury arc of motion. 相似文献
10.