The effects of nimodipine on regional cerebral blood flow, brain water and electrolyte contents in rats with subarachnoid hemorrhage

Secondary cerebral ischemic injury is a major cause of mortality and disability from subarachnoid hemorrhage (SAH). In this study, the protective effects of nimodipine were investigated. Rat SAH models were divided into a sham-operated group, a saline-controlled, and a nimodipine-treated group by an endovascular piercing method. Nimodipine, 100 microg/kg BW was injected intraperitoneally 30 minutes before operation and was repeated every 6 hours. Dynamic changes in cortical regional cerebral blood flow (rCBF) using a laser Doppler flow-meter probe, and somatosensory evoked potentials (SEP) were estimated. Brain water content, sodium, potassium and calcium contents at different time points were determined. rCBF, latency of SEP, brain water and electrolyte contents did not statistically change in sham-operated rats. In saline-controlled rats, rCBF decreased immediately after SAH, and stabilized at low levels within 24 hours. The latency of SEP delayed gradually after SAH. Brain water and sodium increased, while potassium decreased at 6 hours and 24 hours. Brain calcium content increased significantly from 1 hour to 24 hours after induction of SAH. Extents of alterations of the above parameters caused by SAH in the nimodipine-treated group were less than those in the saline-controlled group, statistically. In conclusion, nimodipine partly prevents a decrease in cerebral blood supply and attenuates secondary cerebral ischemic injury after SAH.     

HPV16与新疆维吾尔族食管鳞癌的相关性

目的:调查新疆维吾尔族食管鳞癌患者中人乳头瘤状病毒(HPV)16型的感染率.方法:采用PCR技术检测82例新疆维吾尔族食管鳞癌和80例癌旁正常食管黏膜石蜡包埋组织HPV16的感染率,分析其与新疆维吾尔族食管鳞癌发生的关联性.结果:在新疆维吾尔族食管鳞癌组织中,HPV16型检出率为31.7%(26/82),与对照组12.5%(10/80)相比,差异有统计学意义(X2=8.643,P<0.05);按照年龄、性别、病理分化程度及临床分期对维吾尔族食管鳞癌中的HPV16感染状况比较,差异均无统计学意义(X2=0.301、0.149、2.876、0.105,均P>0.05).结论:HPV16型感染与新疆维吾尔族食管鳞癌的发生存在一定的相关性,但与患者的年龄、性别、病理分化程度及临床分期无明显的关联性.     

Thermal Decomposition Kinetics and Compatibility of 3,5-difluoro-2,4,6-trinitroanisole (DFTNAN)

In this paper, the thermal decomposition behavior of 3,5-difluoro-2,4,6-trinitroanisole (DFTNAN) was studied by differential scanning calorimetry (DSC) and thermogravimetry (TG) by using different heating rates (2, 5, 10, 15 °C·min⁻¹). Subsequently, the kinetic and thermodynamic parameters of non-isothermal thermal decomposition of DFTNAN were calculated. The critical temperature of thermal explosion (Tb) and self-accelerating decomposition temperature (TASDT) were determined to be 249.03 °C and 226.33 °C, respectively. The compatibility of DFTNAN with a number of high explosives (cyclo-1,3,5-trimethylene-2,4,6-trinitramine (RDX), 1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaaza-tetracyclo-[5.5.0.05,9.03,11]-dodecane (CL-20) and dihydroxylammonium 5,5’-bistetrazole-1,1’-diolate (TKX-50)) was studied at different mass ratios using DSC. The criteria to judge the compatibility between the materials were based on a standardization agreement (STANAG 4147). The thermodynamic study results revealed that DFTNAN possessed superior thermal safety and stability. The experimental of compatibility results indicated that the mass ratios of the high explosives in the DFTNAN/RDX, DFTNAN/HMX and DFTNAN/CL-20 compositions more than 40%, 60% and 70% exhibited good compatibility, whereas DFTNAN/TKX-50 demonstrated poor compatibility.     

误诊为缺血性卒中并溶栓治疗的高颈段硬脊膜动静脉瘘1例报道

正1病例介绍患者女性,60岁,右利手。因"突发右侧肢体无力、麻木2小时"于2017年7月8日入当地医院。患者于2017年7月8日15:00左右打完麻将回家时突发右侧肢体无力,表现为右手开门拧钥匙困难,伴有颈部、后背部及右侧肋部疼痛,合并小便失禁。送至当地医院急查头颅CT提示     

大鼠局灶性脑缺血模型缺血半暗带的定位研究

目的通过用组织病理学方法结合局部脑血流量(rCBF)测定,对大鼠局灶性脑缺血动物模型缺血半暗带的解剖定位进行初步探讨.方法用线栓法制成大鼠大脑中动脉(MCA)闭塞及再通模型、采用TTC染色法观察分组动物在MCA闭塞的不同时间再灌流48h后脑梗死灶的分布,并用氢清除法测定缺血区rCBF的变化.结果大鼠MCA闭塞1～2h,梗死灶主要位于缺血侧的外侧尾壳核和额顶叶皮质下部;MCA闭塞3h、梗死灶向周围扩大;MCA闭塞4h、梗死灶进一步扩展至大部分新皮质区,但与MCA闭塞6h时无明显区别.MCA闭塞后缺血侧的内侧尾壳核和额顶叶皮质上部rCBF下降至对照组的27%～45%.结论大鼠MCA闭塞后在2～3h的时间窗以内恢复血流,可使位于缺血边缘区的内侧尾壳核和额顶叶皮质上部脑组织被挽救,该区域可能相当于缺血半暗带的等值区.     

Vlasov-Fokker-Planck Simulations for High-Power Laser-Plasma Interactions

A review is presented on our recent Vlasov-Fokker-Planck (VFP) simulation code development and applications for high-power laser-plasma interactions. Numerical schemes are described for solving the kinetic VFP equation with both electron-electron and electron-ion collisions in one-spatial and two-velocity (1D2V) coordinates. They are based on the positive and flux conservation method and the finite volume method, and these two methods can insure the particle number conservation. Our simulation code can deal with problems in high-power laser/beam-plasma interactions, where highly non-Maxwellian electron distribution functions usually develop and the widely-used perturbation theories with the weak anisotropy assumption of the electron distribution function are no longer in point. We present some new results on three typical problems: firstly the plasma current generation in strong direct current electric fields beyond Spitzer-Härm's transport theory, secondly the inverse bremsstrahlung absorption at high laser intensity beyond Langdon's theory, and thirdly the heat transport with steep temperature and/or density gradients in laser-produced plasma. Finally, numerical parameters, performance, the particle number conservation, and the energy conservation in these simulations are provided.     

Blockade of cholecystokinin-2 receptor and cyclooxygenase-2 synergistically induces cell apoptosis, and inhibits the proliferation of human gastric cancer cells in vitro

Gastrin and cyclooxygenase-2 (COX-2) play important roles in the carcinogenesis and progression of gastric cancer. However, it remains unknown whether the combination of cholecystokinin-2 (CCK-2) receptor antagonist plus COX-2 inhibitor exerts synergistic anti-tumor effects on human gastric cancer. Here, we demonstrated that the combination of AG-041R (a CCK-2 receptor antagonist) plus NS-398 (a selective COX-2 inhibitor) treatment had synergistic effects on proliferation inhibition, apoptosis induction, down-regulation of Bcl-2 and up-regulation of Bax expression in MKN-45 cells. These results indicate that simultaneous targeting of CCK-2 receptor and COX-2 may inhibit gastric cancer development more effectively than targeting either molecule alone.     

老龄大鼠局灶性脑缺血后细胞周期素表达变化及意义

目的:探讨老龄大鼠局灶性脑缺血后细胞周期素表达意义。方法:应用原位末端标记、原位分子杂交、免疫组织化学等方法,分别对老龄大鼠局灶性脑缺血后４ｈ,２４ｈ,５ｄ脑组织中的凋亡细胞,ＣｙｃｌｉｎＤｌｍＲＮＡ,ＣｙｃｌｉｎＤ１,ＣｙｃｌｉｎＡ和ＣｙｃｌｉｎＢ１蛋白表达进行观察。结果:ＣｙｃｌｉｎＤ１ ｍＲＮＡ,ＣｙｃｌｉｎＤ１及 ＣｙｃｌｉｎＢ１蛋白阳性细胞主要见于缺血灶周围,其分布范围及动态变化规律与Ｔｕｎｅｌ阳性细胞一致。但未见ＣｙｃｌｉｎＡ蛋白表达。结论:ＣｙｃｌｉｎＤ１,ＣｙｃｌｉｎＢ１参与了局灶性脑缺血后神经细胞的凋亡过程,此过程可能是细胞周期异常调控的结果。