Arnold-Chiari畸形合并脊髓空洞症的外科治疗

目的：寻求Arnold—Chiari畸形合并脊髓空洞症的病因、发病机制和确实合适的手术方案及术式。方法：通过回顾性分析天津医科大学总医院神经外科在1990年至2003年间收治的143例病例，对比不同手术方式术前术后MRI和临床症状的变化，寻找其间的规律。结果：术前MRI显示，有空洞者比单纯小脑扁桃体下疝者后颅窝更加紧密。术后症状均缓解，MRI显示空洞均减小，但后颅窝减压术者可见小脑扁桃体回缩，而脊髓空洞一腹腔分流术者小脑扁桃体回缩不明显。结论：Arnold—Chiari畸形合并脊髓空洞症是多因素引起的疾病，不能以单一因素来解释。脊髓蛛网膜下腔，特别是颅颈结合部的脑脊液循环障碍，是各种病因的共同点。因此，解除脑脊液循环障碍是治疗这种疾病的关键环节和最终目的。     

Detection of structural and numerical chromosomal abnormalities by ACM-FISH analysis in sperm of oligozoospermic infertility patients

BACKGROUND: Modern reproductive technologies are enabling the treatment of infertile men with severe disturbances of spermatogenesis. The possibility of elevated frequencies of genetically and chromosomally defective sperm has become an issue of concern with the increased usage of ICSI, which can enable men with severely impaired sperm production to father children. Several papers have been published reporting aneuploidy in oligozoospermic patients, but relatively little is known about chromosome structural aberrations in the sperm of these patients. METHODS: We examined sperm from infertile, oligozoospermic individuals for structural and numerical chromosomal abnormalities using a multicolour ACM fluorescence in situ hybridization (FISH) assay that utilizes DNA probes specific for three regions of chromosome 1 to detect human sperm that carry numerical chromosomal abnormalities plus two categories of structural aberrations: duplications and deletions of 1pter and 1cen, and chromosomal breaks within the 1cen-1q12 region. RESULTS: There was a significant increase in the average frequencies of sperm with duplications and deletions in the infertility patients compared with the healthy concurrent controls. There was also a significantly elevated level of breaks within the 1cen-1q12 region. There was no evidence for an increase in chromosome 1 disomy, or in diploidy. CONCLUSIONS: Our data reveal that oligozoospermia is associated with chromosomal structural abnormalities, suggesting that oligozoospermic men carry a higher burden of transmissible, chromosome damage. The findings raise the possibility of elevated levels of transmissible chromosomal defects following ICSI treatment.     

Effect of coriaria lactone-activated astrocyte-conditioned medium on the cerebral TNF-α of normal rats

Summary To explore the effect of coriaria lactone (CL)-activated astrocyte-conditioned medium on the cerebral TNF-α of normal rats, the CL-activated astrocyte-conditioned medium (ACM) was injected into the lateral ventricle of SD rats. The rats were observed for behavioral changes, and the changes of the expression of TNF-α in the cerebral cortex and hippocampus were immunohistochemically examined by employing SP method. TNF-α level was assessed by means of radioimmunoassay in homogenate of cerebral cortex and hippocampus as well as cerebrospinal fluid. Seizure episodes were observed in ACM group 30 min after the ACM injection, but they were not observed in the control group. Immunohistochemical detection showed that the immunoreaction of TNF-α in hippocampus and cerebral cortex of rats were stronger than that of the control group 4 h after the ACM injection (P<0.05). In this group, the concentrations of TNF-α in homogenate of cerebral cortex and hippocampus and cerebrospinal fluid were higher than those of the control group (P<0.05). It is suggested that the ACM activated by CL can enhance the expression of TNF-α in normal rats, and is related to epileptogenesis. LI Zhongyu, female, born in 1972, Lecturer This project was supported by a grant from the key National Nature Scientific Foundation of China (No. 30230140).     

羟基丁酸-羟基辛酸共聚体/脱细胞软骨基质支架的细胞黏附性

背景：羟基丁酸-羟基辛酸共聚体[poly(hydroxybutyrate-co-hydroxyoctanoate)，PHBHOx]是一种新型的多聚羟基烷酸类材料，具有优良的可塑性、生物相容性、生物可降解性等性能，但同其他酯类材料相似，PHBHOx亲水性能较差，单纯PHBHOx材料支架细胞黏附性能明显不足。 目的：观察羟基丁酸-羟基辛酸共聚体/脱细胞软骨基质支架的细胞黏附性。 方法：取新鲜猪膝关节表面透明软骨，采用非离子型去污剂Triton X-100、低渗Tris-HCl以及Dna酶和Rna酶等进行脱细胞处理。低温粉碎后与PHBHOx以不同比例复合，采用溶剂浇铸-颗粒沥滤技术制备支架。分离培养猪关节软骨细胞，进行细胞-支架黏附实验并通过MTT比色法和扫描电镜观察软骨细胞在支架上的黏附存活情况。 结果与结论：PHBHOx/脱细胞软骨基质支架的细胞黏附率较对照组显著提高，软骨细胞在支架上黏附紧密，生长良好。提示复合脱细胞软骨基质可以明显提高单纯PHBHOx支架的细胞黏附性能。 关键词：羟基丁酸-羟基辛酸共聚体；脱细胞软骨基质；支架材料；细胞黏附性 doi:10.3969/j.issn.1673-8225.2010.25.007     

ACM对tbOOH致原代神经细胞损伤及凋亡的影响

目的　探讨星形胶质细胞条件培养液 (ACM)对叔丁基脂氢过氧化物 (tb OOH)诱导的原代神经细胞损伤和凋亡的影响。方法　分离培养 SD大鼠大脑皮层星形胶质细胞和神经细胞 ,以 ACM和 /或 tb OOH处理神经细胞后 ,采用 MTT法和光镜评估细胞的生存力 ,Hoechst332 5法观察细胞凋亡 (率 )的变化 ;共聚焦显微镜检测细胞内 Bcl- 2表达。结果　与 tb OOH处理组相比 ,ACM可降低神经细胞损伤和凋亡 (P<0 .0 5) ,增加细胞内 Bcl- 2表达。结论　 ACM有保护氧自由基 tb OOH诱导的神经细胞损伤和凋亡作用 ,Bcl- 2表达增加可能参与了 ACM的抑制凋亡。     

某化工企业塑料改性剂（ACM）建设项目职业病危害预评价

目的识别、评价和分析某塑料改性剂建设项目可能产生及存在的职业病危害因素,预测其对劳动者健康的危害程度,提出相应职业病危害防护措施。方法选择与本建设项目类似工艺的企业进行类比调查,采用类比法、检查表法相结合的原则进行评价。结果本建设项目选址与总体布局、生产设备布局、拟采取的职业病防护设施设计、辅助用室的卫生设施配置等基本符合国家有关规定。本项目可能产生的主要职业病危害因素有：粉尘、化学毒物（包括氯、氯化氢、氢氧化钠）、噪声。类比企业粉尘、氯化氢、噪声检测合格率100.0%,氯气检测点11个,合格率90.9%。结论本建设项目属于严重职业病危害项目,项目拟采取的职业病危害防护设施基本符合国家职业卫生标准和卫生要求,该项目是可行的。     

2019 HRS expert consensus statement on evaluation,risk stratification,and management of arrhythmogenic cardiomyopathy

Arrhythmogenic cardiomyopathy (ACM) is an arrhythmogenic disorder of the myocardium not secondary to ischemic, hypertensive, or valvular heart disease. ACM incorporates a broad spectrum of genetic, systemic, infectious, and inflammatory disorders. This designation includes, but is not limited to, arrhythmogenic right/left ventricular cardiomyopathy, cardiac amyloidosis, sarcoidosis, Chagas disease, and left ventricular noncompaction. The ACM phenotype overlaps with other cardiomyopathies, particularly dilated cardiomyopathy with arrhythmia presentation that may be associated with ventricular dilatation and/or impaired systolic function. This expert consensus statement provides the clinician with guidance on evaluation and management of ACM and includes clinically relevant information on genetics and disease mechanisms. PICO questions were utilized to evaluate contemporary evidence and provide clinical guidance related to exercise in arrhythmogenic right ventricular cardiomyopathy. Recommendations were developed and approved by an expert writing group, after a systematic literature search with evidence tables, and discussion of their own clinical experience, to present the current knowledge in the field. Each recommendation is presented using the Class of Recommendation and Level of Evidence system formulated by the American College of Cardiology and the American Heart Association and is accompanied by references and explanatory text to provide essential context. The ongoing recognition of the genetic basis of ACM provides the opportunity to examine the diverse triggers and potential common pathway for the development of disease and arrhythmia.     

Validation of the Transferrin Receptor for Drug Targeting to Brain Capillary Endothelial Cells In Vitro

Recently, we have shown that transferrin (Tf) is actively endocytosed by the Tf R on primary cultured bovine brain capillary endothelial cells (BCEC). The objective of this investigation is to determine whether the Tf R can facilitate endocytosis of a (protein) model drug, using Tf as a targeting vector. Secondly, the mechanism of endocytosis was investigated. Horseradish peroxidase (HRP, 40 kDa) was chosen as a model drug, since it normally does not cross the blood–brain barrier (BBB) and its concentration in biological media can be easily quantified.

Tf-HRP conjugates (1:1) are actively and specifically endocytosed by BCEC in vitro in a concentration and time-dependent manner. At an applied concentration of 3 μg/ml, association (a combination of binding and endocytosis) of Tf-HRP reached equilibrium at a concentration of 2 ng/mg cell protein after 1 h of incubation at 37°C. This was approximately 3-fold higher compared to binding at 4°C (0.6 ng/mg cell protein). Association of Tf-HRP was compared to BSA-HRP. After 2 h of incubation at 37°C association levels were 5.2 and 2.5 ng/mg cell protein, for Tf-HRP and BSA-HRP, respectively. Under those conditions, association of Tf-HRP could be inhibited to approximately 30% of total association by an excess of non-conjugated Tf, but not with BSA, while association of BSA-HRP could be inhibited by both proteins. Furthermore, by using specific inhibitors of endocytotic processes, it was shown that association of Tf-HRP is via clathrin-coated vesicles. Association of Tf-HRP is inhibited by phenylarsine oxide (an inhibitor of clathrin-mediated endocytosis) to 0.4 ng/mg cell protein, but not by indomethacin, which inhibits formation of caveolae. Finally, following iron scavenging by deferoxamine mesylate (DFO, resulting in a higher Tf R expression) a 5-fold increase in association of Tf-HRP to 15.8 ng/mg cell protein was observed.

In conclusion, the Tf R is potentially suitable for targeting of a (protein) cargo to the BBB and to facilitate its endocytosis by the BCEC.     

A fast doubly hybrid density functional method close to chemical accuracy using a local opposite spin ansatz

We develop and validate the XYGJ-OS functional, based on the adiabatic connection formalism and Görling-Levy perturbation theory to second order and using the opposite-spin (OS) ansatz combined with locality of electron correlation. XYGJ-OS with local implementation scales as N³ with an overall accuracy of 1.28 kcal/mol for thermochemistry, bond dissociation energies, reaction barrier heights, and nonbonded interactions, comparable to that of 1.06 kcal/mol for the accurate coupled-cluster based G3 method (scales as N⁷) and much better than many popular density functional theory methods: B3LYP (4.98), PBE0 (4.36), and PBE (12.10).