Conformations of neurotensin in solution and in membrane environments studied by 2-D NMR spectroscopy

Two-dimensional HOHAHA and ROESY nuclear magnetic resonance techniques are used to obtain complete proton resonance assignments and to perform a conformational investigation of the neuropeptide neurotensin (pGlu-Leu-Tyr-Glu-Asn-Lys-Pro-Arg-Arg-Pro-Tyr-Ile-Leu) in aqueous solution, methanol, and membrane-mimetic [deuterated sodium dodecylsulfate (SDS)] environments. Results suggest the absence of discernible elements of secondary structure in water and methanol. ROESY spectra confirm that Lys-Pro and Arg-Pro peptide bonds are all-trans, but that a significant population of cis Arg-Pro bonds arises in aqueous solution, which increases in the environment of SDS micelles. The conformational ensemble of the peptide is observed to narrow as it becomes bound through its cationic mid-region to SDS micelles, with the accompanying advent of local extended structure. The overall results indicate the inherent conformational flexibility of neurotensin, and emphasize the environmental dependence of conformation in peptides of medium length.     

Studies on the relationship between transaldolase activity and testosterone synthesis in Leydig cells of pubertalmice

Objective: To study the relationship between transaldolase activity, protein expression and testosterone synthesis in Leydig cells of pubertal mice. Methods: Leydig cells were cultured for 2 hours and 8 hours, to the Stimulation Group, hCG was added and to the Controls, only the vehicle. The testosterone concentration was then determined by enzyme-linked immunoadsordent assay (ELISA) and the transaldolase activity and protein expression by Western blot. Results: (1) Both the testosterone concentration and the transaldolase activity in both Stimulation Groups were significantly higher than those in the corresponding Controls (2 h: p<0.05-0.01; 8 h: P<0.001); (2) The ratios of the A isoform, the B isoform and the total transaldolase protein to β-actin between the Stimulation and Control Groups did not differ signifi-cantly. Conclusion: hCG stimulates the transaldolase activity as well as the testosterone synthesis in the Leydig cells of pubertal mice, indicating a positive relationship between them.     

超声引导胶原酶治疗外侧型腰椎间盘突出症

目的探讨超声引导胶原酶治疗外侧型腰椎间盘突出症的疗效及安全性.方法在相应椎间盘突出的棘突间,旁开1.5～2.5cm处经皮穿刺,采用超声引导定位,穿刺成功后,先进行加压试验,再进行麻醉试验,无腰麻征象后,将胶原酶注入到突出的椎间盘内或周围.结果 231例病人出院时的优良率为92.21%,有效率为99.57%;随访1～5年的优良率为92.65%,有效率为99.58%.近期与远期疗效比较无显著性差异(χ2=0.129,P＞0.05).结论利用超声引导监测、定位,注射胶原酶治疗外侧型腰椎间盘突出症,安全性强、有效率高.     

用ELISA检测肺癌患者血清中Endostatin的变化

目的建立快速敏感的ELISA方法检测肺癌患者血清内皮抑素(Endostatin)。方法对41例肺癌患者及22例良性肺病患者进行血清Endostatin测定并与20例正常人进行比较。结果肺癌患者体内Endostatin水平高于良性肺病患者和正常人。结论快捷的ELISA检测法可以成为人们在临床及基础研究Endostatin的新方法。     

原发性输尿管癌31例临床分析

目的：提高原发性输尿管癌的术前诊断水平。方法：对南京医科大学第一附属医院1989-2002年间收治的31例原发性输尿管癌的临床资料进行回顾性分析。结果：31例中，肉眼血尿22例(71．0％)，腰痛11例(35，5％)。B超、静脉肾盂造影(IVU)、CT和逆行造影检查的阳性率分别为输尿管腔内占位4例(13．0％)、输尿管腔内占位3例(11．5％)、膀胱或合并膀胱占位8例(36．4％)，输尿管充盈缺损6例(40．0％)。29例患者经手术治疗，其中13例行患侧肾、输尿管、膀胱袖状切除。结论：老年患者反复发作的腰痛及血尿应考虑原发性输尿管癌的可能，造影诊断对本病有较高价值，应作CT及MRU无创检查。     

49Sibutramine accelerates gastric emptying, inhibits intestinal motility in conscious dogs

Fasting interdigestive myoelectric complex (IMC) and postprandial gastroduodenal myoelectric activities are regulated by motilin and leptin, respectively (L. Zhou 2005). This study is to observe whether electrical acupuncture points could increase fasting gastroduodenal IMC and postprandial activities, as well as increase the release of motilin and leptin. Methods: Bipolar platinum electrodes were implanted on the serosa of antrum and duodenum in 10 conscious Wistar rats to record IMC and postprandial digestive myoelectric activities. We acupunctured Points Zusanli (S‐36), Tianshu (S‐25), and Liangmen (S‐21) during phase I of IMC (Frequency 20~100 Hz, Strengthen 12~16 mA, period 90 min) and compared with non‐specific electric stimulation (sham acupuncture) group. Serum motilin and leptin level was measured by RIA. Results: (1) Acupuncture points could shorten markedly phase I of antroduodenal IMC and increase the period of phase III (P < 0.01). Acupuncture points also increased the number of spike burst of antral and duodenal slow wave by (121.24 ± 20.0)% and (97.34 ± 15.20)% (compared with control group, P < 0.01). In postprandial period, acupuncture points could increase the number of spike burst of antral and duodenal slow wave by (142.52 ± 23.50)% and (102.48 ± 13.25)% (compared with control group, P < 0.01). (2) When acupuncture points increased the number of spike burst of IMC in fasting state, serum motilin concentration also increased, which was (74.56 ± 8.20)% more than control group (P < 0.01). When acupuncture points with meal, serum leptin concentration increased with myoelectric activity, which was (139.84 ± 20.25)% more than control group (P < 0.01). There was no change of motilin and leptin concentration in non‐specific electric stimulation group. (3) Cutting off subphrenic vagus nerves could totally block the effect of acupuncture points on antroduodenal myoelectric activities and release of motilin and leptin. Conclusions: Acupuncture points could effectively increase fasting and postprandial antroduodenal myoelectric activities. This effect is mediated by motilin and leptin, respectively.     

血管重塑对大鼠血管成形术后再狭窄的影响

目的：建立大鼠颈动脉再狭窄模型，原位灌注固定取材。评价PTA后血管重塑（VR）的动态变化规律，定量分析血管重塑在血管再狭窄过程中的变化及作用。方法：制作70只SD雄性大鼠颈总动脉再狭窄模型，分原位灌注实验组、对照组，于术后1h、3、7、14、28和42天原位灌注固定取材，行HE染色、Masson染色，观察标本血管狭窄情况。结果：①血管重塑指数（VRI）在PTA后即刻最大，3天组明显降低，7天组稍有增大，其后不断减小，剩余血管腔面积百分比同VRI的变化曲线基本一致。②FFA后，血管腔面积总体呈逐渐缩小趋势，内弹力板围绕面积（IELA）1h组较对照组明显增大，3天组较1h组明显缩小，14、28、42天组较对照组明显缩小。外弹力板围绕面积（EELA）逐渐缩小。EELA、IELA的变化与血管腔面积变化呈正相关。③VRI与血管腔面积的变化呈正相关，新生内膜面积与剩余狭窄率、血管腔面积无直线相关。结论：再狭窄过程中存在扩张性重塑和收缩性重塑现象，管腔的狭窄与否取决于血管重塑指数的变化，而不是新生内膜的变化，新生内膜的形成是血管重塑过程中的一部分。IELA和EELA可作为判断管腔狭窄及评价血管重塑的指标。     

BIOEQUIVALENCE BETWEEN rhGH FOR RECONSTITUTION AND READY-TO-USE rhGH IN TWO LIQUID FORMULATIONS

Objective To evaluate the bioequivalence between recombinant human growth hormone （rhGH） for reconstitution, and two dosages of liquid formulation of rhGH [ （151U） 5mg or （301U） lOmg per 3ml ]. Methods The study drugs were tested in a randomized, single-blind and three-period crossover studies in 24 healthy male subjects. The three drugs were administered by subcutaneous injection at a dose of O. 21U/kg body weight. A continuous somatostatin infusion was given in order to suppress the secretion of endogenous GH. The ve- nous blood samples were drawn at different time points to test the serum concentration of GH. The pharmacokinetic parameters were analyzed by statistical methods. Results 90% confidence intervals （CI） of AUC0-24h among three products were all within 80% - 125% interval （ 103. 4% - 116. 5%, 105. 7% - 119. 6% and 91.9% - 103. 7%, respectively）, and the Cls of C,~ among three products were all within 70% - 143% interval （91.9% - 114. 0%, 103. 7% -127. 2% and 81.6% -97. 4%, respectively）. There was no statisitical difference of tmax among all the three products. Conclusion These data demonstrate that there is bioequivalence between rhGH for reconstitution and two liquid formulations of rhGH.     

Developmental changes of glutamate acid decarboxylase 67 in mouse brain after hypoxia ischemia

Objective To study the developmental changes of glutamic acid decarboxylase-67 (GAD-67, a GABA synthetic enzyme) in normal and hypoxic ischemic (HI) brain. Methods C57/BL6 mice on postnatal day (P) 5, 9, 21 and 60, corresponding developmentally to premature, term, juvenile and adult human brain were investigated by using both Western blot and immunohistochemistry methods either in normal condition or after hypoxic ischemic insult. Results The immunoreactivity of GAD67 was up regulated with brain development and significant difference was seen between mature (P21, P60) and immature (P5, P9) brain. GAD67 immunoreactivity decreased in the ipsilateral hemisphere in all the ages after hypoxia ischemia (HI) insult, but, significant decrease was only seen in the immature brain. Double labeling of GAD67 and cell death marker, TUNEL, in the cortex at 8h post-HI in the P9 mice showed that (15.6±7.0)% TUNEL positive cells were GAD67 positive which was higher than that of P60 mice. Conclusion These data suggest that GABAergic neurons in immature brain were more vulnerable to HI insult than that of mature brain.