Mass spectrometric identification of citrullination sites and immunohistochemical detection of citrullinated glial fibrillary acidic protein in Alzheimer's disease brains

Peptidylarginine deiminases (PADs) are posttranslational modification enzymes that convert protein arginine to citrulline residues in a calcium ion‐dependent manner. Previously, we reported the abnormal accumulation of citrullinated proteins and the increase in the amount of PAD2 in hippocampi from Alzheimer's disease (AD) patients. Moreover, glial fibrillary acidic protein (GFAP), an astrocyte‐specific marker protein, and vimentin were identified as citrullinated proteins by using two‐dimensional gel electrophoresis and MALDI‐TOF mass spectrometry. To clarify the substrate specificity of PADs against GFAP, we prepared recombinant human (rh)PAD1, rhPAD2, rhPAD3, rhPAD4, and rhGFAP. After incubation of rhGFAP with rhPAD1, rhPAD2, rhPAD3, and rhPAD4, citrullinated (cit‐)rhGFAP was detected by Western blotting. The citrullination of rhGFAP by rhPAD2 was unique, specific, and time dependent; additionally, rhPAD1 slightly citrullinated rhGFAP. We then generated eight anti‐cit‐rhGFAP monoclonal antibodies, CTGF‐125, ?128, ?129, ?1212, ?1213, ?1221, ?122R, and ?1224R, which reacted specifically with cit‐rhGFAP. Two of those eight monoclonal antibodies, CTGF‐122R and ?1224R, reacted with both cit‐rhGFAP and rhGFAP in Western blots. By using the CTGF‐1221 antibody and a tandem mass spectrometer, we identified the two independent citrullination sites (R270Cit and R416Cit) of cit‐rhGFAP. Immunohistochemical analysis with CTGF‐1221 antibody revealed cit‐GFAP staining in the hippocampus of AD brain, and the cit‐GFAP‐positive cells appeared to be astrocyte‐like cells. These collective results strongly suggest that PAD2 is responsible for the citrullination of GFAP in the progression of AD and that the monoclonal antibody CTGF‐1221, reacting with cit‐GFAP at R270Cit and R416Cit, is useful for immunohistochemical investigation of AD brains. © 2015 Wiley Periodicals, Inc.     

Ischemic Conditioning Is Safe and Effective for Octo- and Nonagenarians in Stroke Prevention and Treatment

Symptomatic intracranial arterial stenosis (SIAS) is very common in octo- and nonagenarians, especially in the Chinese population, and is likely the most common cause of stroke recurrence worldwide. Clinical trials demonstrate that endovascular treatment, such as stenting, may not be suitable for octogenarians with systemic diseases. Hence, less invasive methods for the octogenarian patients are urgently needed. Our previous study (unique identifier: {"type":"clinical-trial","attrs":{"text":"NCT01321749","term_id":"NCT01321749"}}NCT01321749) showed that repetitive bilateral arm ischemic preconditioning (BAIPC) reduced the incidence of stroke recurrence by improving cerebral perfusion (confirmed by single photon emission computed tomography and transcranial Doppler sonography) in patients younger than 80 years of age; however, the safety and effectiveness of BAIPC on stroke prevention in octo- and nonagenarians with SIAS are still unclear. The objective of this study was to evaluate the safety and effectiveness of BAIPC in reducing stroke recurrence in octo- and nonagenarian patients with SIAS. Fifty-eight patients with SIAS were enrolled in this randomized controlled prospective study for 180 consecutive days. All patients enrolled in the study received standard medical management. Patients in the BAIPC group (n = 30) underwent 5 cycles consisting of bilateral arm ischemia followed by reperfusion for 5 min each twice daily. Those in the control group (n = 28) underwent sham-BAIPC twice daily. Blood pressure, heart rate, local skin status, plasma myoglobin, and plasma levels of thrombotic and inflammatory markers were documented in both groups before beginning the study and for the first 30 days. Finally, the incidences of stroke recurrence and magnetic resonance imaging during the 180 days of treatment were compared. Compared with the control, BAIPC had no adverse effects on blood pressure, heart rate, local skin integrity, or plasma myoglobin, and did not induce cerebral hemorrhage in the studied cohort. BAIPC reduced plasma high sensitive C-reactive protein, interleukin-6, plasminogen activator inhibitor-1, leukocyte count, and platelet aggregation rate and elevated plasma tissue plasminogen activator (all p < 0.01). In 180 days, 2 infarctions and 7 transient ischemic attacks were observed in the BAIPC group compared with 8 infarctions and 11 transient ischemic attacks in the sham BAIPC group (p < 0.05). BAIPC may safely inhibit stroke recurrence, protect against brain ischemia, and ameliorate plasma biomarkers of inflammation and coagulation in octo- and nonagenarians with SIAS. A multicenter trial is ongoing.Clinical Trial Registration: www.clinicaltrials.gov, unique identifier: {"type":"clinical-trial","attrs":{"text":"NCT01570231","term_id":"NCT01570231"}}NCT01570231.

Electronic supplementary material

The online version of this article (doi:10.1007/s13311-015-0358-6) contains supplementary material, which is available to authorized users.Key Words: Remote ischemic preconditioning, octogenarian, nonagenarians, intracranial arterial stenosis, stroke, recurrence     

麻醉穿刺时地塞米松对神经根损伤的疗效

目的探讨麻醉穿刺时地塞米松对神经根损伤的临床效果。方法腰硬联合麻醉穿刺过程中神经根损伤的剖腹产手术56患者随机分为观察组和对照组。观察组在手术结束前硬膜外注射地塞米松5mg加0.9%氯化钠注射液19mL。对照组注射0.9%氯化钠注射液10mL。比较2组患者的手术、麻醉时间和治疗效果。结果 2组患者手术时间和麻醉时间差异无统计学意义(P>0.05)。观察组有效率100%,无并发症发生,对照组有效率71.4%,并发症发生率为28.6%,差异有统计学意义(P<0.05)。结论地塞米松对腰硬联合麻醉穿刺时造成的神经根损伤作用效果明显,并发症发生率较低,疗效确切。     

巴彦乌拉铀矿周围饮用井水中总放射性水平调查

目的 调查巴彦乌拉铀矿周围饮用井水中总放射性水平。方法 采集2020年巴彦乌拉铀矿周围枯水期和丰水期饮用井水174份,以及居民家中经过滤后的饮用井水5份。分析枯水期和丰水期总α和总β放射性水平是否存在差异,总放射性水平与距离铀矿中心不同位置的关系,并对居民家中过滤后的饮用井水进行放射性水平调查。采用低本底α、β放射性测量仪测量分析其放射性水平。结果 巴彦乌拉铀矿周围饮用井水中,枯水期总α范围为0.024~ 2.468 Bq/L, 平均为(0.605±0.507)Bq/L,总β变化范围为0.125~1.395 Bq/L,平均为(0.420±0.235)Bq/L。丰水期总α变化范围为0.049~2.988 Bq/L,平均为(0.825±0.605)Bq/L,总β变化范围为0.059~1.623 Bq/L,平均为(0.506±0.265)Bq/L。距离铀矿中心位置水样的总放射性水平均值关系为10 km>30 km>20 km。结论 巴彦乌拉铀矿周围饮用井水中的放射性活度偏高,丰水期水样中总α、总β放射性水平均大于枯水期,放射性水平较未开采前未见升高。     

基于基因表达综合数据库筛选调控急性T淋巴细胞白血病超高剂量率放疗敏感性的枢纽基因

目的 通过生物信息学方法对基因表达综合(GEO)数据库中超高剂量率(FLASH)放疗的数据进行分析,寻找参与调控急性T淋巴细胞白血病FLASH放疗敏感性的枢纽(Hub)基因。方法 从GEO数据库中下载和提取接受FLASH放疗恶性肿瘤基因表达谱芯片数据,采用R软件进行差异基因的筛选,并对这些基因进行生物学功能、信号传导通路等分析。通过STRING在线软件分析差异基因的蛋白质相互作用(PPI) 网络,Cytoscape插件筛选Hub基因。最后,应用肿瘤基因组图谱(TCGA)和GTEx数据库验证Hub基因在急性T淋巴细胞白血病中的表达情况。结果 自GEO数据库中获得GSE100718芯片数据,共有12 800个基因与急性T淋巴细胞白血病放疗敏感性相关。选择表达量显著改变的61个基因进行进一步分析,这些基因参与代谢、应激反应、免疫应答等生物学过程。主要涉及氧化磷酸化、未折叠蛋白应答、脂质代谢等信号转导通路。通过PPI分析筛选出的Hub基因及后续验证表明HSPA5及SCD参与调控FLASH放疗敏感性,且在合并TRD/LMO2融合基因的急性T淋巴细胞白血病中显著高表达。结论 通过生物信息学分析可以有效筛选出调控FLASH放疗敏感性的Hub基因,基因表达谱可用于指导肿瘤患者分层以实现精准放疗。     

放射卫生的科学问题与关键技术展望

新中国成立70多年来,放射卫生工作得到了党和政府的高度重视,全国放射卫生队伍做了大量工作,成绩卓著。本文围绕职业照射、医疗照射、公众照射和应急照射的安全与防护,以及辐射健康效应及其机制等领域,未来数年内需要解决的科学问题和技术发展瓶颈进行梳理凝炼,以期给国内放射卫生领域相关单位和专家的研究工作提供参考和借鉴。     

An evaluation of the response to neoadjuvant chemotherapy for osteosarcoma of extremities: PERCIST versus RECIST 1.1 criteria after long-term follow-up

Annals of Nuclear Medicine - The aim of this study was to compare the recent Positron emission tomography (PET) Response Criteria in Solid Tumors (PERCIST) and Response Evaluation Criteria in Solid...