The trajectory of the sympathetic nerve fibers to the rat cochlea as revealed by anterograde and retrograde WGA-HRP tracing

Wheat germ agglutinin-horseradish peroxidase conjugate was injected in the unilateral superior cervical ganglion (SCG), and the projection pathways of postganglionic sympathetic nerve fibers innervating the cochlea were traced in the rat. The labeled axons advanced along the internal carotid artery (ICA), and a few advanced caudally in the major petrosal nerve (MPN) and entered the facial nerve, while the majority ran rostral to the pterygopalatine ganglion at the point where they crossed the MPN in the carotid canal. The rest of the labeled fibers remained on the surface of the ICA and advanced to the cranial cavity. Most of the labeled fibers along the facial nerve joined the cochlear nerve and finally reached the osseous spiral lamina through the spiral ganglion. Some of the labeled fibers ran along the anterior inferior cerebellar artery from the basilar artery which was previously thought to have been the only pathway. We could not find any labeled fiber on the modiolar artery from anterior inferior cerebellar artery in the cochlea. These observations are consistent with our hypothesis that the sympathetic fibers innervating the neural tissues or related structures follow nerve fibers and meninges as matrices of projection pathways rather than arteries.     

缺血－再灌注兔心肌肌浆网自由基的测定

应用电子自旋共振波谱仪（ＥＳＲ）直接检测了缺血－再灌注兔心肌肌浆网自由基的变化，以探讨肌质网系统与氧自由基的关系。实验中将２０只兔随机分为再灌注对照组、超氧化物歧化酶（ＳＯＤ）组、ＡＴＰ－氯化镁组和人参皂甙Ｒｅ组。实验结果，ｇ值２．００４６处为半醌自由基波谱，其相对浓度各组依次为７８．９４±２．１２６，１４．４６±２．８６，２０．６５±７．６５，１４．６６±３．６７（ｘ±ＳＤ），对照组与用药组均有显著性差异（Ｐ＜０．０５），表明缺血－再灌注兔心肌肌浆网产生大量的自由基，用ＥＳＲ可以直接检测到半醌自由基，外源性高能磷酸盐制剂ＡＴＰ－氯化镁及人参皂甙Ｒｅ与超氧化物歧化酶一样，发挥清除兔心肌肌浆网自由基的作用。     

Correlation between epidermal growth factor receptor concentration and the growth of human gastric cancer xenografts in nude mice.

Seven human gastric cancer xenografts with different concentrations of EGF receptor were established in nude mice. The expression of EGF receptor in the tumors was demonstrated by Western blotting with anti-EGF receptor antibody, binding assay with 125I-EGF and immunohistochemistry with anti-EGF receptor antibody. Western blotting revealed EGF receptor doublet bands at molecular masses of 150 KDa and 170 KDa in all of the samples. The concentration of 125I-EGF binding activity in the tumors ranged from 36.0 to 11,000 fmol/mg protein, with a mean of 345 fmol/mg protein. EGF receptor was also demonstrated immunohistochemically on the apical border of the glands and the cell membrane of the tumor cells. There seemed to be a close correlation between the concentration of 125I-EGF binding activity and the doubling time of these tumors in nude mice (gamma = -0.68). However, no definite correlation was observed between EGF ligand binding and histological features of intestinal type or diffuse type. The expression of EGF receptor appears to facilitate the growth of human gastric cancer xenografts in nude mice.     

Relationship between the thromboxane A2 receptor gene and susceptibility to cerebral infarction.

The risk of cerebral infarction (CI) in an individual is dependent on the interplay between genetic risk factors and environmental influences. Binding of thromboxane A2 (TXA2) to its receptor (TP) modulates thrombosis/hemostasis and plays a significant role in the pathogenesis of CI. The aim of the present study was to investigate the relationship between human TP gene single nucleotide polymorphisms (SNPs) and haplotypes and CI in a Japanese population. A genetic association study was performed in 194 CI patients and 365 non-CI subjects by specifically characterizing 6 SNPs in the human TP gene (rs2271875, rs768963, rs2238634, rs11085026, rs4523 and rs4806942). Analysis demonstrated that there were significant differences in the overall distribution of genotypes and dominant or recessive models of rs2271875 and rs768963 between the CI and the non-CI groups. Multiple logistic regression analysis revealed that the C allele of rs768963 was significantly associated with CI (p = 0.029), even after adjusting for confounding factors (odds ratio: 2.41). Further, the C-T-C haplotype of rs768963-rs2238634-rs4806942 was significantly more frequent in the CI group (23.0%) than in the non-CI group (17.7%). These results suggest that specific SNPs and haplotypes may have utility as genetic markers for the risk of CI and that TP or a neighboring gene is associated with the increased susceptibility to CI.     

Enhancement of the intrinsic defecation reflex by mosapride, a 5-HT4 agonist, in chronically lumbosacral denervated guinea pigs.

The defecation reflex is composed of rectal distension-evoked rectal (R-R) reflex contractions and synchronous internal anal sphincter (R-IAS) reflex relaxations in guinea pigs. These R-R and R-IAS reflexes are controlled via extrinsic sacral excitatory nerve pathway (pelvic nerves), lumbar inhibitory nerve pathways (colonic nerves) and by intrinsic cholinergic excitatory and nitrergic inhibitory nerve pathways. The effect of mosapride (a prokinetic benzamide) on the intrinsic reflexes, mediated via enteric 5-HT(4) receptors, was evaluated by measuring the mechanical activity of the rectum and IAS in anesthetized guinea pigs using an intrinsic R-R and R-IAS reflex model resulting from chronic (two to nine days) lumbosacral denervation (PITH). In this model, the myenteric plexus remains undamaged and the distribution of myenteric and intramuscular interstitial cells of Cajal is unchanged. Although R-R and R-IAS reflex patterns markedly changed, the reflex indices (reflex pressure or force curve-time integral) of both the R-R contractions and the synchronous R-IAS relaxations were unchanged. The frequency of the spontaneous R and IAS motility was also unchanged. Mosapride (0.1-1.0 mg/kg) dose-dependently increased both intrinsic R-R (maximum: 1.82) and R-IAS reflex indices (maximum: 2.76) from that of the control (1.0) 6-9 days following chronic PITH. The dose-response curve was similar to that in the intact guinea pig, and had shifted to the left from that in the guinea pig after acute PITH. A specific 5-HT(4) receptor antagonist, GR 113808 (1.0 mg/kg), decreased both reflex indices by approximately 50% and antagonized the effect of mosapride 1.0 mg/kg. This was quite different from the result in the intact guinea pig where GR 113808 (1.0 mg/kg) did not affect either of the reflex indices. The present results indicate that mosapride enhanced the intrinsic R-R and R-IAS reflexes and functionally compensated for the deprivation of extrinsic innervation. The actions of mosapride were mediated through endogenously active, intrinsic 5-HT(4) receptors which may be post-synaptically located in the myenteric plexus of the anorectum.     

肝功能衰竭大鼠脑水通道蛋白-4表达与MR扩散加权成像的相关性研究

目的研究水通道蛋白-4（AQP-4）在急、慢性肝功能衰竭时脑组织中的表达规律，应用MR扩散加权成像（DWI）探讨脑水肿的分子生物学机制。方法雄性SD大鼠65只采用数字表法随机分为急性组（25只）、慢性组（25只）和对照组（15只），分别诱发急、慢性肝功能衰竭。行DWI观察异常信号分布情况，测量顶部皮质区、外侧部皮质区和邻近侧脑室区的DWI信号强度。处死后进行血氨检测，取与DWI检查对应的大脑层面切片行病理观察、免疫组织化学及逆转录．聚合酶链式反应（RT—PCR）检测，检测AQP-4蛋白表达水平，并进行统计学分析。结果急性组肝细胞坏死及脑水肿明显，慢性组呈肝硬化改变，脑水肿不明显。血氨浓度急性组、慢性组和对照组分别为（516±46）、（158±26）和（148±32）μmol／L，差异有统计学意义（F=188．325，P〈0．01）。顶部皮质区、外侧部皮质区和邻近侧脑室区的DWI信号强度对照组分别为516±160、727±183和656±181；急性组分别为1766±438、1223±503和1216±446；慢性组分别为700±213、820±263和713±243，差异均有统计学意义（F值分别为44．612、3．422和5．581，P值均〈0．05）。相应区域AQP-4蛋白表达水平（用平均灰度值表示）对照组分别为7379±1617、8104±2093和4851±2178；急性组分别为9580±2616、11057±2334和2949±1735；慢性组分别为12137±2332、11135±3102和7688±2925，3组间差异均有统计学意义（F值分别为11．414、4．602和7．002，P值均〈0．05）。急性组AQP-4蛋白表达水平与DWI信号强度有相关性（r=0．756，P〈0．05），慢性组AQP-4蛋白表达水平与DWI信号强度无相关关系（r=0．236，P〉0．05）。结论在急、慢性肝功能衰竭中血氨增高是导致脑内能量代谢异常、星形胶质细胞内AQP-4mRNA和蛋白表达增加的主要因素；DWI技术发现的信号异常可很好的反映脑水肿、AQP-4蛋白表达异常的范围、程度。     

营养素食预防化疗患者便秘的效果观察

目的 观察营养素食预防化疗患者便秘的效果。方法 选择128例化疗患者，随机分为观察组和对照组各61例，对照组常规正常饮食，观察组于化疗开始当天实施营养素食．连续7～10d，比较两组患者便秘发生率及体重、血红蛋白、白蛋白等指标。结果　对照组便秘发生率显著高于观察组（P〈0．01）；两组化疗后营养指标比较，差异无显著性意义（均P〉0．05）。结论　营养素食对化疗患者便秘有较好的预防作用。     

网络环境下高校图书馆功能的嬗变及其应对策略

随着网络信息技术的发展，数字化、网络化信息资源的开发与利用迅速普及，高校图书馆的功能也发生显著的变化：以印刷文献为中心向以数字信息为中心转变；由单一化服务向多样化服务转变；由人工服务向智能化控制转变；由传统的图书存贮、借阅中心将发展成为现代化信息的交流中转站或导航站。本文分析和阐述了网络环境下高校图书馆功能的嬗变特点和规律，提出了具有实践意义的应对策略。