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Histone deacetylases (HDACs) constitute a super-family of enzymes grouped into four major classes (Class I–IV) that deacetylate histone tails leading to chromatin condensation and gene repression. Whether stroke-induced oligodendrogenesis is related to the expression of individual HDACs in the oligodendrocyte lineage has not been investigated. We found that 2 days after stroke, oligodendrocyte progenitor cells (OPCs) and mature oligodendrocytes (OLGs) were substantially reduced in the peri-infarct corpus callosum, whereas at 7 days after stroke, a robust increase in OPCs and OLGs was observed. Ischemic brains isolated from rats sacrificed 7 days after stroke were used to test levels of individual members of Class I (1 and 2) and Class II (4 and 5) HDACs in white matter oligodendrocytes during stroke-induced oligodendrogenesis. Double immunohistochemistry analysis revealed that stroke substantially increased the number of NG2+ OPCs with nuclear HDAC1 and HDAC2 immunoreactivity and cytoplasmic HDAC4 which were associated with augmentation of proliferating OPCs, as determined by BrdU and Ki67 double reactive cells after stroke. A decrease in HDAC1 and an increase in HDAC2 immunoreactivity were detected in mature adenomatous polyposis coli (APC) positive OLGs, which paralleled an increase in newly generated BrdU positive OLGs in the peri-infarct corpus callosum. Concurrently, stroke substantially decreased the acetylation levels of histones H3 and H4 in both OPCs and OLGs. Taken together, these findings demonstrate that stroke induces distinct profiles of Class I and Class II HDACs in white matter OPCs and OLGs, suggesting that the individual members of Class I and II HDACs play divergent roles in the regulation of OPC proliferation and differentiation during brain repair after stroke.  相似文献   
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The HERV‐W family of human endogenous retroviruses represents a group of numerous sequences that show close similarity in genetic composition. It has been documented that some members of HERV‐W–derived expression products are supposed to play significant role in humans' pathology, such as multiple sclerosis or schizophrenia. Other members of the family are necessary to orchestrate physiological processes (eg, ERVWE1 coding syncytin‐1 that is engaged in syncytiotrophoblast formation). Therefore, an assay that would allow the recognition of particular form of HERV‐W members is highly desirable. A peptide nucleic acid (PNA)–mediated technique for the discrimination between multiple sclerosis‐associated retrovirus and ERVWE1 sequence has been developed. The assay uses a PNA probe that, being fully complementary to the ERVWE1 but not to multiple sclerosis‐associated retrovirus (MSRV) template, shows high selective potential. Single‐stranded DNA binding protein facilitates the PNA‐mediated, sequence‐specific formation of strand invasion complex and, consequently, local DNA unwinding. The target DNA may be then excluded from further analysis in any downstream process such as single‐stranded DNA‐specific exonuclease action. Finally, the reaction conditions have been optimized, and several PNA probes that are targeted toward distinct loci along whole HERV‐W env sequences have been evaluated. We believe that PNA/single‐stranded DNA binding protein–based application has the potential to selectively discriminate particular HERV‐W molecules as they are at least suspected to play pathogenic role in a broad range of medical conditions, from psycho‐neurologic disorders (multiple sclerosis and schizophrenia) and cancers (breast cancer) to that of an auto‐immunologic background (psoriasis and lupus erythematosus).  相似文献   
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目的:探讨乌司他丁联合痰清宁雾化吸入对重症肺炎患者肌钙蛋白水平、心肌酶谱的影响。方法:收集2014年3月至2016年3月于我院治疗的104例重症肺炎患者,52例行常规治疗患者作为对照组,52例于常规治疗基础上行乌司他丁联合痰清宁雾化吸入患者作为观察组,比较两组体征及症状消失时间、肌钙蛋白[心肌肌钙蛋白T(cTnT)、心肌肌钙蛋白I(cTnI)]、心肌酶谱[谷草转氨酶(AST)、乳酸脱氢酶(LDH)\氢丁酸脱氢酶(HBDH)、肌酸激酶同工酶(CK-MB)]、临床症状积分、临床疗效及不良反应的发生情况。结果:观察组体征及症状消失时间明显短对照组(P0.05);治疗后,观察组cTnT、cTnI低于对照组,差异有统计学意义(P0.05);观察组AST、LDH、HBDH、CK-CB低于对照组,差异有统计学意义(P0.05);观察组临床症状积分低于对照组(P0.05);观察组有效率96.15%高于对照组82.69%(P0.05);两组不良反应发生率比较无统计学差异(P0.05)。结论:乌司他丁联合痰清宁雾化吸入治疗重症肺炎的临床疗效好,且可有效降低肌钙蛋白及心肌酶谱水平,减轻心肌损伤。  相似文献   
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Epidemiological evidence indicates an elevated risk for stroke among stressed persons, in general, and among individuals who have lost their job, in particular. We, therefore, tested the hypothesis that stroke accounted for a larger fraction of deaths during the Great Recession than expected from other deaths and from trends, cycles, and other forms of autocorrelation. Based on vital statistics death data from California spanning 132 months from January 2000 through December 2010, we found support for the hypothesis. These findings appear attributable to non-Hispanic white men, who experienced a 5% increase in their monthly odds of stroke-attributable death. Total mortality in this group, however, did not increase. Findings suggest that 879 deaths among older white men shifted from other causes to stroke during the 36 months following the start of the Great Recession. We infer the Great Recession may have affected social, biologic, and behavioral risk factors that altered the life histories of older white men in ways that shifted mortality risk toward stroke.  相似文献   
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ObjectiveApproximately one third of patients who have suffered a stroke develop spasticity. Since clinical observations that spasticity in the elderly population is lower after stroke, and disagreement about risk factors between different authors, an analysis is performed on the variables that influence the development of spasticity.The objective of the study is to determine the how many factors influence spasticity outcome, and the prevalence of spasticity in patients who have suffered a stroke and require intensive rehabilitation treatment.MethodA retrospective assessment was carried out on a total of 554 patients from two neurorehabilitation centres. A record was made of sociodemographic data, aetiology, type and location of stroke, motor and sensory deficits, language and swallowing impairment, incontinence, cognitive and mood state. Spasticity levels at admission and at the third month were studied in 462 patients using the Ashworth scale. Multivariate regression analyses were used to assess the risk factors for spasticity present at the third month after stroke.ResultsThe mean age of the patients was 67.3 years, of which 67.1% were men, and with ischemic aetiology in 76.5%. On admission 31.4% of patients had spasticity, and this increased to 54.8% at the 3rd month. The absolute risk factor for spasticity was motor index (OR 1.04; 95% CI 1.03-1.05). When this factor was omitted, the variables with predictive ability were: age less than 75 years (OR 0.52; 95% CI 0.30-0.90), sensory impairment (OR 0.66; 95% CI 0.37-1.20), and lower Barthel index score (OR 1.02; 95% CI 1.01-1.03). There was no significant relationship for gender, physiopathological mechanism (ischaemic/haemorrhagic), stroke location, aphasia, or cognitive impairment.ConclusionThe prevalence of spasticity in stroke at third month of follow-up was 54.8%. Motor index is the independent predictor of spasticity. Patients younger than 75 years old, with sensory impairment and low Barthel index score are more likely to develop spasticity.  相似文献   
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The structure of the retroviral proteinase from avian myeloblastosis associated virus (MAV) has been determined and refined at 2.2 A resolution. This structure is compared with those of homologous proteinases from Rous sarcoma virus (RSV) and human immunodeficiency type 1 virus (HIV). Through comparison with the structure of a proteinase-inhibitor complex from HIV, a model of a complex between MAV proteinase and a peptide substrate has been generated. Examination of this model suggests structural basis for the diverse specifications of viral proteinases.  相似文献   
9.
An increase of methylase activity is often related to neoplastic transformation. SAH, the natural inhibitor of transmethylases, does not inhibit cell transformation induced by RSV, in contrast to one of its synthetic analogues, SIBA. This inefficiency was thought to be due to the rapid metabolism of SAH by transformed cells. We now show, that, on the contrary, 70 % of the added amount of SAH disappears in one hour in cell-free extracts of normal cell against only 14 % in extracts of transformed cells. This decreased rate of degradation occurred one day post infection. Cells infected with the non transforming RAV1 degrade SAH at the same rate as normal cells. A decrease of SAH-hydrolase and adenosine deaminase activity was also observed in infected cells. The decrease of the first enzyme seems to be related to the transformed state, whereas that of the second enzyme seems to depend only on infection, since it is also observed in cells infected with RAV1.  相似文献   
10.
Two published case reports described palliation of disease after Seihai-to therapy for refractory aspiration pneumonia caused by recurrent laryngeal nerve paralysis and cerebrovascular disease. We undertook an open-label trial in patients with relapsing aspiration pneumonia. Fifteen patients with relapsing aspiration pneumonia were randomly divided into conventional therapy group (n = 8) or Seihai-to group (n = 7). In Seihai-to group, patients were treated with Seihai-to in addition to conventional therapy (Western medicines). Frequency of feverish days and antibiotics-use, CRP value and chest CT or X-ray findings were compared between the two groups during the study period of 16 weeks. In the Seihai-to group, the latency of swallowing reflex was measured in 6 patients before and after administration of Seihai-to. The mean values of fever index, CRP value and antibiotics-use in the Seihai-to group were decreased significantly, compared with those of the conventional therapy group. However, the latency of the swallowing reflex after 4 weeks of treatment was not significantly changed (p = 0.249), compared with the latency before administration of Seihai-to. No adverse reaction was observed in either group. Seihai-to was effective in reducing relapse of aspiration pneumonia in this small group. Seihai-to might not improve the swallowing reflex, but might instead improve a defense mechanism or excessive inflammation caused by pneumonia in the lower airway. Further evaluation of Seihai-to therapy for patients with aspiration pneumonia in a larger population is warranted.  相似文献   
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