某设备所致脉冲X射线辐射场测量与防护评价

目的 了解某设备实验条件下不同位置脉冲X射线电离辐射水平，提出适当的防护建议。方法 采用热释光测量方法，分别在设备舱周围不同方向不同距离布放热释光剂量计，累积一定数量脉冲辐射后进行测量；采用电离室型X、γ剂量率仪（FJ-347A）实时测量工作状态下不同距离处电离辐射剂量率水平。依据《电离辐射防护与辐射源安全基本标准》（GB18871—2002）规定的职业照射人员和公众个人剂量限值提出不同工作位辐射防护建议。结果 热释光剂量计累计接收3 000个脉冲辐射，设备舱外壁0.01～8.98 mGy，顶部0.01～15.67 mGy，距外壁1～12 m之间0.01～2.18 mGy，工作位0 mGy。工作状态下，X射线剂量率仪测得距设备舱外侧壁1～20 m之间空气比释动能率范围0.26～16 mGy/h。结论 热释光剂量计、电离室型剂量率仪测量结果基本一致，说明两种方法均可用于脉冲X射线测量；工作状态下设备舱外近距离处辐射剂量率较高，可通过采取防护措施或者限制人员工作量以满足辐射防护要求。     

用电子自旋共振成像观测氮氧自由基的透皮特性

在自行研制的电子自旋共振成像(Electron spin resonance imaging, ESRI)系统上建立了活体皮肤电子自旋共振成像的实验模型.观测了氮氧自由基化合物2,2,6,6-四甲基哌啶-1-氧(2,2,6,6-tetramethyl-1-piperidinyloxy,TEMPO)穿透小鼠皮肤组织的动态过程和浓度分布情况.成像结果显示TEMPO化合物对不同方法处理后的皮肤组织的透皮特性有明显差别.TEMPO水溶液难以穿透皮肤,而溶解在二甲基亚枫(Dimethyl sulfoxide,DMSO)中的脂溶性TEMPO溶液可以渗入并穿透皮肤.皮肤表层的角质蛋白对TEMPO有明显的阻隔性, 而且化合物渗入或透过皮肤组织的量具有较强的时间依赖性.本研究结果提示ESRI技术为动态研究某些特殊结构化合物的透皮特性提供了科学有效的分析手段.     

骨质疏松疫苗载体:Qβ病毒样颗粒的表达、鉴定和纯化

 目的 优化表达和纯化方式,制备出具有正确空间结构且纯度和产量较高的骨质疏松疫苗载体Qβ病毒样颗粒(Qβvirus-like particles,Qβ-VLPs)。方法 在基因合成时删除A1基因序列中Qβ衣壳蛋白终止密码子之后的序列,只合成Qβ衣壳蛋白的基因序列。将Qβ衣壳蛋白基因序列克隆到pET30a载体质粒上,用BL21(DE3)、BL21(DE3)pLysS、Rosetta(DE3)三种不同菌株进行蛋白表达,然后用SDS-PAGE和透射电镜验证是否表达出Qβ-VLPs的正确结构。设置2个蛋白表达诱导剂IPTG( Isopropyl β-D-1-thiogalactopyranoside,异丙基-β-D-硫代半乳糖苷)浓度和3种菌体破碎方式,分别优化蛋白表达条件和菌体破碎方案,然后将得到的Qβ-VLPs上清液通过硫酸铵聚沉、高速离心和分子筛分选进行Qβ-VLPs的纯化。结果 仅BL21(DE3)pLysS菌株可以表达出SDS-PAGE中呈现5-6聚体、透射电镜下呈现25~30 nm球形结构的Qβ-VLPs。使用0.5 mM浓度的IPTG表达的Qβ-VLPs产量较0.2 mM时高2.8倍,使用超声破碎菌体的方式可以获得较高的蛋白分离效率。将Qβ-VLPs上清液通过本实验过程中的方案进行纯化后纯度可达90%左右。结论 该实验探索出具有正确空间结构、组成单一且纯度较高的Qβ-VLPs的制备方案,为相关疫苗制备和研究奠定基础。     

Advances in drug development for targeted therapies for glioblastoma

Glioblastoma is the most aggressive primary brain tumor in adults. The prognosis of patients with primary glioblastoma treated with the current standard of care, tumor resection followed by radiation therapy and auxiliary temozolomide, remains poor. Integrative genomic analyses have identified essential core signaling pathways and frequent genetic aberrations, which provide potential drug targets for glioblastoma treatment. Drugs against these therapeutic targets have been developed rapidly in recent years. Although some have shown promising effects on models in preclinical studies, many have shown only modest efficacy in clinical trials. New therapeutic strategies and potent drugs are urgently needed to improve the prognosis of patients with glioblastoma. The goal of this review is to summarize the current advances in drug development for targeted glioblastoma therapies and to reveal the major challenges encountered in clinical trials or treatment. This study will provide new perspectives for future studies of targeted therapeutic drug development and provide insights into the clinical treatment of glioblastoma.     

A case of complete atrioventricular block associated with primary cardiac lymphoma reversed without cardiac pacemaker implantation

Primary cardiac lymphoma (PCL) is a rare malignant lymphoma that is characteristically confined to the heart and/or pericardium. Here, the case of a 70-year-old male patient with complete atrioventricular block (AVB) associated with PCL is presented. The patient had a 10-month history of palpitation and electrocardiogram (ECG) showed a complete AVB. Additionally, transthoracic echocardiography indicated pericardial effusion where atypical lymphoid cells were identified by pericardiocentesis. Subsequent mediastinal lymph node biopsy revealed non-germinal centre diffuse large B-cell lymphoma. Therefore, a diagnosis of PCL was confirmed. As the patient’s vital signs were stable, he was prescribed chemotherapy without pacemaker implantation. After chemotherapy, the patient achieved remission and dynamic ECG demonstrated no recurrence of AVB. The present case demonstrates that although PCL initially manifesting as complete AVB is rare, this possibility should not be ignored when a new AVB without definite aetiology is encountered. In addition, if the vital signs of the patient are stable, pacemaker implantation may be postponed until the treatment effect of chemotherapy has been assessed.     

人胚胎发育过程中间充质干祖细胞与造血细胞间的起源关系探讨

目的探讨人胚胎发育过程中间充质干祖细胞(MSPCs)与造血细胞间的起源关系。方法取发育不同时间药流胚胎,分离不同造血组织消化成单个细胞,于高增殖潜能集落形成细胞(HPP-CFC)培养体系培养10~14 d,倒置显微镜下挑取直径大于0.5 mm的HPP-CFC集落于液体培养体系进行二次培养,对二次培养中出现的贴壁细胞进行扩增并鉴定其细胞表面分子的表达,于不同分化体系鉴定其是否具有MSPCs的分化特性。结果本研究总结了胚胎发育不同时期主动脉-性腺-中肾(AGM)区、卵黄囊、胎肝等不同部位包括HPP-CFC在内的各类造血前体细胞的发育动态,发现从28体节开始,一定比例的AGM区HPP-CFC除能够分化产生造血细胞外,其来源的贴壁细胞具有MSPCs的分化功能,贴壁细胞在淋巴母细胞转化实验中可抑制T细胞的增殖。结论人胚胎AGM区内,部分MSPCs和造血细胞起源于共同前体。     

叶酸对体外胎鼠神经干细胞增殖分化的影响

目的探讨叶酸对体外培养的胚胎大鼠神经干细胞(NSCs)增殖分化的影响。方法采用无血清悬浮培养方法分离培养NSCs,光镜下观察不同时间点各组NSCs形态变化,并采用MTT法、生长曲线法检测叶酸对细胞增殖和功能的影响。培养6天后用含5%胎牛血清的培养基进行分化培养,于分化第7天用免疫荧光技术做Nestin/BrdU双标染色,共聚焦显微镜下观察,每组随机选择8个非重叠视野,计数做统计处理。结果MTT结果显示,两叶酸干预组NSCs增殖较对照组快(P<0.05),分化后免疫荧光双标试验中,两叶酸干预组NSCs增殖率高于正常对照组,且差异有显著性(P<0.05)。结论叶酸可以在一定程度上增强NSCs的增殖能力,促进NSCs的生长与分化。     

Splenic autotransplantation and oesophageal transection anastomosis in patients with portal hypertension(26 years clinical observation)

The surgical treatment methods for cirrhosis patients complicated with portal hypertension are complicated. In this study, we evaluated the effectiveness of a new treatment strategy: splenic auto-transplantation and oesophageal transection anastomosis on 274 patients from three aspects: clinical observation, splenic immunology and portal dynamics. From 1979 to 2005, 274 cirrhosis patients with portal hypertension who underwent the new treatment strategy were followed up to observe different clinical indexes, which were then compared with those of the traditional surgery treatment. From 1999 to 2002, a randomized control trial (RCT) was performed on 40 patients to compare their immune function after operation. From 1994 to 2004, another RCT was carried out on 28 patients to compare the portal dynamics through three-dimensional dynamic contrast enhanced MR angiography (3D DEC MRA) investigation after operation. Among 274 patients (mean age 41.8 years), the emergency operative mortality (4.4%), selective operative mortality (2.2%), complication rate (17.9%), morbidity of hepatic encephalopathy (<1%), bleeding rate of portal hypertension gastritis (PHG) (9.1%), and morbidity of hepatic carcinoma (8%) were similar to those under traditional operation; the spleen immunology function (Tuftsin, IgM) decreased among the groups 2 months after operation. Through 3D DCE MRA, the cross section area, the velocity and volume of blood flow of main portal vein decrease significantly after operation in both groups, the auto transplantation group was significantly lower in velocity and volume of blood flow than in the control group. Splenic auto transplantation and esophageal transection anastomosis are a safe, effective, and reasonable treatment strategy for portal hypertension with varicial bleeding. It can not only correct hypersplenism but also completely stanch blood, and auto transplanted spleen in the retroperitoneal space can preserve immune function and establish abroad collateral circulation.     

TREATING 100 CASES OF HEADACHE BY MAINLY NEEDLING FENGCHI AND TAICHONG

This article introduces the writers' experience in treating 100 cases of headache bymainly needling Fengchi (GB 20) and Taichong (LR 3). It is considered in TCM that headache ismostly caused by pathogenic wind, and there is a saying of "no wind, no headache". The combinationof the two points can expel both endogenous and exogenous wind. So we treat headache mainly withneedling Fengchi and Taichong. The result is good, especially for cluster headache and psychicheadache.'