预变神经段修复神经缺损的实验研究

目的探讨不同预变时间组移植神经对神经再生的影响。方法以ＳＤ大鼠的不同预变时间组的尺神经作为移植神经，修复其正中神经的缺损。实验侧按移植神经预变时间的不同分为０、１、２、３、４、８周共６组，每组６只ＳＤ大鼠。移植后１２周，检测实验侧趾屈肌群的张力、最大收缩力、再生神经的形态及神经轴突的截面积。结果用预变１周的尺神经修复正中神经后，其趾屈肌群的张力及最大收缩力的恢复率达到正常对照组的８１．１％及８５．９％。显微镜下观察，预变１周组和其它各时间组相比，其再生的神经轴突最多，发育最成熟。结论用预变１周的神经段修复神经缺损，其神经再生能力最佳     

金属离子及氨基糖对大鼠肾脏N－乙酰氨基葡萄糖转移酶Ⅲ活性测定的影响

采用反相ＨＰＬＣ荧光测定法对大鼠肾脏Ｎ－乙酰氨基葡萄糖转移酶（ＧｎＴ）Ⅲ活性测定时二价金属离子及氨基糖的影响进行了研究。结果表明：ＧｎＴⅢ必须有二价金属离子激活，最佳激活离子为Ｍｎ￣（２＋）离子，其次为Ｍｇ￣（２＋）离子；二协金属离子对ＧｎＴⅢ的激活作用依次为Ｍｎ￣（２＋）＞Ｍｇ（２＋）＞Ｃｏ（２＋）＞Ｃａ￣（２＋）＞Ｎｉ￣（２＋）＞Ｂａ￣（２＋）＞Ｚｎ￣（２＋）。四种氨基糖（Ｎ－乙酰氨基葡萄糖ＧｌｃＮＡｃ，Ｎ－乙酰氨基半轧糖ＧａＩＮＡｃ，氨基葡萄糖ＧｌｃＮ，氨基半乳糖ＧａｌＮ），除ＧｌｃＮ使ＧｎＴ活性增加外，其余三种对ＧｎＴⅢ均有不同程度的抑制作用。     

Lung surfactant gelation induced by epithelial cells exposed to air pollution or oxidative stress

Lung surfactant lowers surface tension and adjusts interfacial rheology to facilitate breathing. A novel instrument, the interfacial stress rheometer (ISR), uses an oscillating magnetic needle to measure the shear viscosity and elasticity of a surfactant monolayer at the air-water interface. The ISR reveals that calf lung surfactant, Infasurf, exhibits remarkable fluidity, even when exposed to air pollution residual oil fly ash (ROFA), hydrogen peroxide (H2O2), or conditioned media from resting A549 alveolar epithelial cells (AEC). However, when Infasurf is exposed to a subphase of the soluble fraction of ROFA- or H2O2-treated AEC conditioned media, there is a prominent increase in surfactant elasticity and viscosity, representing two-dimensional gelation. Surfactant gelation is decreased when ROFA-AEC are pretreated with inhibitors of cellular reactive oxygen species (ROS), or with a mitochondrial anion channel inhibitor, as well as when A549-rho0 cells that lack mitochondrial DNA and functional electron transport are investigated. These results implicate both mitochondrial and nonmitochondrial ROS generation in ROFA-AEC-induced surfactant gelation. A549 cells treated with H2O2 demonstrate a dose-dependent increase in lung surfactant gelation. The ISR is a unique and sensitive instrument to characterize surfactant gelation induced by oxidatively stressed AEC.     

Additive Antinociception between Intrathecal Sildenafil and Morphine in the Rat Formalin Test

The possible characteristics of spinal interaction between sildenafil (phosphodiesterase 5 inhibitor) and morphine on formalin-induced nociception in rats was examined. Then the role of the opioid receptor in the effect of sildenafil was further investigated. Catheters were inserted into the intrathecal space of male Sprague-Dawley rats. For induction of pain, 50 µL of 5% formalin solution was applied to the hind-paw. Isobolographic analysis was used for the evaluation of drug interaction between sildenafil and morphine. Furthermore, naloxone was intrathecally given to verify the involvement of the opioid receptor in the antinociception of sildenafil. Both sildenafil and morphine produced an antinociceptive effect during phase 1 and phase 2 in the formalin test. The isobolographic analysis revealed an additive interaction after intrathecal delivery of the sildenafil-morphine mixture in both phases. Intrathecal naloxone reversed the antinociception of sildenafil in both phases. These results suggest that sildenafil, morphine, and the mixture of the two drugs are effective against acute pain and facilitated pain state at the spinal level. Thus, the spinal combination of sildenafil with morphine may be useful in the management of the same state. Furthermore, the opioid receptor is contributable to the antinocieptive mechanism of sildenafil at the spinal level.     

Bacteremia due to Moraxella atlantae in a cancer patient

A gram-negative alkaline phosphatase- and pyrrolidone peptidase-positive rod-shaped bacterium (CCUG 45702) was isolated from two aerobic blood cultures from a female cancer patient. No identification could be reached using phenotypic techniques. Amplification of the tRNA intergenic spacers revealed fragments with lengths of 116, 133, and 270 bp, but no such pattern was present in our reference library. Sequencing of the 16S rRNA gene revealed its identity as Moraxella atlantae, a species isolated only rarely and published only once as causing infection. In retrospect, the phenotypic characteristics fit the identification as M. atlantae (formerly known as CDC group M-3). Comparative 16S rRNA sequence analysis indicates that M. atlantae, M. lincolnii, and M. osloensis might constitute three separate genera within the MORAXELLACEAE: After treatment with amoxicillin-clavulanic acid for 2 days, fever subsided and the patient was dismissed.     

休克大鼠小肠微循环灌流量和血清TNF的变化及多巴胺的作用

在39只失血性休克大鼠中，用激光多普勒微循环血流计及ELISA法测定静脉注射多巴胺前后小肠微循环增流量及血清TNF浓度的变化。结果发现随休克发展，小肠微循环血液灌流量进行性减少，TNF浓度升高。多巴胺（40μg／100gB．W．）治疗可增加小肠微循环血液油流量和降低血清TNF浓度。两者间呈显著性相关（r＝0．897，P＜0．01）。作者认为，多巴胺通过增加小肠微循环血液灌流量，改善肠壁屏障功能，减少内毒素入血，从而降低血清TNF浓度，保护了脏器功能和减轻细胞损伤。     

老年学习记忆减退大鼠齿状回突触的定量研究

据老年大鼠在Ｍｏｒｒｉｓ水迷宫中的行为表现，将其分为老年学习记忆减退和学习记忆正常两部分，采用透射电镜观察、拍片，对齿状回中分子层触的数量和大小进行体视学定量分析。     

Identification and characterization of clinical isolates of members of the Staphylococcus sciuri group

A total of 28 staphylococcal isolates from human clinical specimens belonging to the Staphylococcus sciuri group were identified and characterized. The API Staph and ID32 STAPH correctly identified S. sciuri and S. lentus but not S. vitulinus strains. Identification to the subspecies level was possible only by a PCR-based method.     

Involvement of ERK, p38 and NF-kappaB signal transduction in regulation of TLR2, TLR4 and TLR9 gene expression induced by lipopolysaccharide in mouse dendritic cells

Toll-like receptors (TLR) are sentinel receptors capable of recognizing pathogen-associated molecule patterns (PAMP) such as lipopolysaccharide (LPS) and CpG-containing oligonucleotides (CpG ODN). TLR2 and TLR4 are major receptors for Gram-positive and Gram-negative bacterial cell wall components, respectively. TLR9 is necessary for CpG signalling. LPS or CpG ODN can activate immature dendritic cells (DC) and induce DC maturation characterized by production of cytokines, up-regulation of co-stimulatory molecules, and increased ability to activate T cells. However, little is known regarding the regulation of TLR gene expression in mouse DC. In this study, we investigated the regulation of TLR2, TLR4 and TLR9 gene expression by LPS in murine immature DC. TLR2, TLR4 and TLR9 mRNA were up-regulated following LPS stimulation. The up-regulation of TLR9 expression coincided with significantly increased production of tumour necrosis factor-alpha induced by LPS plus CpG ODN. While inhibition of extracellular signal-related kinase and NF-kappaB activation suppressed the up-regulation of the expression of TLR2, TLR4 and TLR9 mRNA, inhibition of p38 kinase prevented the up-regulation of TLR2 and TLR4 mRNA expression but enhanced the up-regulation of TLR9 expression. These results demonstrated that TLR2, TLR4 and TLR9 gene expression was differently regulated by LPS in mouse immature DC. Up-regulation of TLR2, TLR4 and TLR9 expression by LPS might promote the overall responses of DC to bacteria and help to explain the synergy between LPS and other bacterial products in the induction of cytokine production.     

血液透析对尿毒症患者血液流变性的影响

研究单次及长期维持血液透析时尿毒症患者血液流变性改变的影响。结果表明，单次血透后，红细胞比积明显升高，红细胞刚性明显降低；血浆粘度、红细胞聚集指数、Ｃａｓｓｏｎ粘度、血液屈服应力及低切至高切的全血粘度无明显改变。维持血透患者的红细胞比积、血浆粘度、红细胞聚集指数、Ｃａｓｓｏｎ粘度、血液屈服应力均无明显改变。进一步研究发现，单次血透后血浆渗透比明显降低．这可能是引起红细胞比积升高、红细胞刚性降低的原因之一。