Secondary hypoxemia exacerbates the reduction of visual discrimination accuracy and neuronal cell density in the dorsal lateral geniculate nucleus resulting from fluid percussion injury

The purpose of this study was to determine the impact of secondary hypoxemia on visual discrimination accuracy after parasagittal fluid percussion injury (FPI). Rats lived singly in test cages, where they were trained to repeatedly execute a flicker-frequency visual discrimination for food. After learning was complete, all rats were surgically prepared and then retested over the following 4-5 days to ensure recovery to presurgery levels of performance. Rats were then assigned to one of three groups [FPI + Hypoxia (IH), FPI + Normoxia (IN), or Sham Injury + Hypoxia (SH)] and were anesthetized with halothane delivered by compressed air. Immediately after injury or sham injury, rats in groups IH and SH were switched to a 13% O2 source to continue halothane anesthesia for 30 min before being returned to their test cages. Anesthesia for rats in group IN was maintained using compressed air for 30 min after injury. FPI significantly reduced visual discrimination accuracy and food intake, and increased incorrect choices. Thirty minutes of immediate posttraumatic hypoxemia significantly (1) exacerbated the FPI-induced reductions of visual discrimination accuracy and food intake, (2) further increased numbers of incorrect choices, and (3) delayed the progressive recovery of visual discrimination accuracy. Thionine stains of midbrain coronal sections revealed that, in addition to the loss of neurons seen in several thalamic nuclei following FPI, cell loss in the ipsilateral dorsal lateral geniculate nucleus (dLG) was significantly greater after FPI and hypoxemia than after FPI alone. In contrast, neuropathological changes were not evident following hypoxemia alone. These results show that, although hypoxemia alone was without effect, posttraumatic hypoxemia exacerbates FPI-induced reductions in visual discrimination accuracy and secondary hypoxemia interferes with control of the rat's choices by flicker frequency, perhaps in part as a result of neuronal loss and fiber degeneration in the dLG. These results additionally confirm the utility of this visual discrimination procedure as a sensitive, noninvasive means of assessing behavioral function after experimental traumatic brain injury.     

The role of VCAM-l/VLA-4 in the activation of allogenic T cells by murine macrophages

Vascular cell adhesion molecule 1 (VCAM-1) is a member of immunoglobulin superfamily. The principal ligand for VCAM-1 is integrin α4β/VLA-4 (very late antigen 4). It was reported that VCAM-1 was expressed on macrophages and dendritic cells, but little is known about its function on these professional antigen presenting cells (APC). The present study was performed to investigate the expression of VCAM-1 on macrophages and the role of VCAM-l/VLA-4 in the activation of allogenic T cells by murine macrophages. We analyzed VCAM-1 expression on peritoneal macrophages and macrophage cell line J774A.1 by fluorescence-activated cell sorting (FACS). Using neutralizing antibodies, we further analyzed the role of VCAM-l/VLA-4 interaction in macrophage and allogenic T cell mixed lymphocyte reaction (MLR). We found that VCAM-1 was constitutively expressed on macrophages and its expression level was upregulated by soluble tumor associated antigen (freeze-thaw lysates of FBL-3 leukemia cells) and TNF-a. In MLR assays, we observed that blocking VCAM-l/VLA-4 interaction with anti-VCAM-1 or anti-VLA-4 mAbs caused significant inhibition of the proliferative response and IL-2 production. These results suggest that VCAM-lon macrophages not only facilitates the cell-to-cell contact through adhesive interaction but also plays a role in the costimulation of T cells via its interaction with VLA-4 on the T cells. This work was supported by grants from the National Natural Science Foundation of China.No. (39730420). This is one of papers of the special issue on gene therapy research (Chin J Cancer Res Vol. 9 No. 4 December, 1997).     

JNK/SAPKs信号转导通路在榄香烯抗肝癌效应中的作用

目的:探讨JNK/SAPKs信号转导通路在榄香烯抗肝癌效应中的作用,为阐明榄香烯抗癌效应的分子机制提供参考.方法:气相色谱法检测榄香烯在Hca-F肝癌细胞内的分布.透射电镜观察SMMC7721凋亡细胞的超微结构变化.利用Western-blotting对榄香烯处理的HepG2肝癌细胞JNK/SAPKs进行的活性分析.利用RT-PCR检测榄香烯处理的SMMC7721肝癌细胞的DAXX基因表达.结果:榄香烯标准品在8.42 min时出现洗脱峰.榄香烯处理3 h后,SMMC7721细胞开始发生具有凋亡特征的变化.榄香烯处理组HepG2细胞的JNK/SAPKs激酶活性次于热休克处理组,高于对照组.榄香烯处理的SMMC7721细胞组未见DAXX基因的表达.结论:榄香烯能够进入细胞内.其引起的肿瘤细胞凋亡可能是通过活化JNK/SAPKs来诱导的.DAXX传人途径在榄香烯诱导的JNK/SAPKs活化过程中可能不起主要作用.     

金属硫蛋白在食管鳞癌中的表达及其与增殖凋亡的关系

目的:探讨金属硫蛋白在食管鳞癌中的表达及其与癌细胞增殖、凋亡的关系。方法:采用免疫组化法检测92例食管鳞癌组织中的金属硫蛋白(MT)、增殖细胞核相关抗原(Ki-67抗原)的表达,并用TUNEL法检测细胞凋亡指数。结果:92例食管鳞癌标本中65例MT呈阳性表达,阳性率为70.6%,明显高于正常食管粘膜上皮组织(3/20,P<0.01);MT表达与食管鳞癌患者年龄、性别、浸润深度及病变长度无关,而与组织分化程度、TNM分期、淋巴结转移密切相关,MT与Ki-67抗原表达强度呈正相关,Pearson列联系数=0.227(P<0.05)。随MT表达强度的增加,癌组织凋亡指数逐渐降低。结论:MT表达与食管鳞癌的发生、发展密切相关,MT能促进癌细胞增殖,抑制细胞凋亡,可作为食管鳞癌治疗的新靶点。     

丹参酮ⅡA对兔髂动脉球囊损伤后胶原生成抑制的效应观察

目的:观察兔髂动脉损伤后,丹参酮ⅡA治疗组中膜平滑肌细胞(SMC)周围胶原变化的趋势.方法:取体重2.5～3kg纯种雄性新西兰大白兔30只,球囊导管扩张法制作左髂动脉内膜球囊损伤模型,术后分配到治疗组和对照组.治疗组丹参酮ⅡA稀释静脉注射,疗程6天;对照组采用等量生理盐水静脉注射.术后7天、14天和28天处死实验兔,将左侧髂动脉取出制作石蜡切片,并作胶原染色.结论:术后7天治疗组和对照组胶原纤维染色均不明显,术后14天和28天对照组SMCs周围可见胶原染色阳性,红染增多;治疗组14天SMCs周围也可见红染增多,但28天红染不明显;两组差异以术后28天明显(P=0.017);胶原染色随时间变化的趋势有统计学意义(P=0.005).结论:丹参酮ⅡA有抑制血管损伤后细胞外基质堆积的作用,从而可能有防治术后再狭窄的效应.     

针刺为主治疗缺血性视乳头病变临床观察

目的:观察针刺与西药治疗缺血性视乳头病变的疗效差异.方法:31例患者以针刺治疗为主,辅以穴位注射.对于发病2周之内者,局部配合球后注射.记录治疗前后视力、视野的变化.结果:治疗前后视力、视野比较,差异均有极显著性意义(P<0.001).结论:该疗法是改善缺血性视乳头病变患者视功能的有效方法.     

针刺配合复方三白散治疗胃十二指肠溃疡穿孔59例

目的 探讨中西医结合治疗胃十二指肠溃疡穿孔的有效治疗方法.方法 将117例患者随机分为两组,治疗组采用自拟复方三白散、针刺治疗,对照组仅用西医常规治疗.结果 经统计学处理,两组痊愈率、总有效率、平均住院时间及3年总复发率比较均有显著性差异(P均＜0.01).结论 中西医结合治疗胃十二指肠溃疡穿孔,可缩短住院时间,减轻痛苦,提高非手术治愈率.     

颧骨缝牵张成骨过程中组织超微结构变化的研究

目的:观察天然骨缝牵张成骨过程中组织和细胞超微结构的变化。方法:对牵张成骨的缝区组织经过系列处理,进行超薄切片、透射电镜观察。结果:间充质细胞在牵引早期大量增生,并不断分化为成纤维细胞和成骨细胞,后2种细胞的超微结构显示出具有活跃的合成和分泌功能。1周标本成纤维细胞沿牵引力的长轴方向排列,胞核增大,在其周围包绕着发达并扩张的内质网系统;3周标本大量增生活跃的成骨细胞和成纤维细胞,成骨细胞核仁增大、粗面内质网扩张、核糖体丰富、线粒体增多、富含紧密排列的嵴;5、8周标本中骨细胞形成并发育成熟,骨基质逐渐矿化,清晰可见新形成的胶原纤维、哈氏管,以及骨基质矿化的过程。结论:三维牵张过程中,成纤维细胞、成骨细胞活跃,缝区形成新骨。     

Characterization of the volatile organic compounds produced from green coffee in different years by gas chromatography ion mobility spectrometry

The effect of storage time on green coffee volatile organic compounds (VOCs) was studied by their separation via head space solid-phase microextraction and identification via gas chromatography-ion mobility spectrometry. In total, 38 kinds of VOCs, mainly composed of alcohols, aldehydes, esters and ketones, were identified. The fingerprint showed that the VOCs produced by green coffee in different years had obvious differences, especially, acrolein, 3-methylbutyl acetate, butanoic acid, heptan-3-ol, and so on, that could be used to predict the storage time. In addition, with the increase of storage time, the contents of butanal, ethanol, dimethyl sulfide, propanal, butan-2-one had no obvious change, and could be considered as typical aroma characteristics of green coffee or special aroma components for variety identification. Meanwhile, principal component analysis (PCA) and “nearest neighbor” fingerprint analysis could also effectively distinguish green coffee with different storage times. Comprehensive analysis showed that GC-IMS technology could provide strong and favorable support for coffee storage.

The effect of storage time on green coffee VOCs was studied by their separation via HS-SPME and identification via GC-MS.