In Vitro and in Vivo Evaluation of Whole and Half Tablets of Sustained-Release Adinazolam Mesylate

The mechanism of release from sustained-release adinazolam mesylate tablets was assessed by the Higuchi equation and by analysis of drug release profiles through 60% released using the Peppas equation. Computed values of the diffusional exponent, n, ranged from 0.59 to 0.66. Values of n in this range are consistent with a mixed mechanism of release, with diffusion of drug through the hydrated polymer matrix and relaxation of this matrix being the principal processes controlling release. The rate of in vitro drug release was increased for half tablets relative to whole tablets and is attributed to an increase in the surface to volume ratio of half tablets of about 16%. This increase in surface-to-volume ratio of half tablets was reflected by an increase in the constant, k, from the Peppas equation of 20–23% and by an increase in the slope of Higuchi plots of 12–18% for four lots of tablets. In vivo/in vitro relationships from two bioavailability studies were thoroughly evaluated. Using either a linear or a quadratic relationship, an in vivo/in vitro correlation exists for sustained-release adinazolam mesylate tablets.     

Spinal canal narrowing during simulated frontal impact

Between 23 and 70% of occupants involved in frontal impacts sustain cervical spine injuries, many with neurological involvement. It has been hypothesized that cervical spinal cord compression and injury may explain the variable neurological profile described by frontal impact victims. The goals of the present study, using a biofidelic whole cervical spine model with muscle force replication, were to quantify canal pinch diameter (CPD) narrowing during frontal impact and to evaluate the potential for cord compression. The biofidelic model and a sled apparatus were used to simulate frontal impacts at 4, 6, 8, and 10 g horizontal accelerations of the T1 vertebra. The CPD was measured in the intact specimen in the neutral posture (neutral posture CPD), under static sagittal pure moments of 1.5 Nm (pre-impact CPD), during dynamic frontal impact (dynamic impact CPD), and again under static pure moments following each impact (post-impact CPD). Frontal impact caused significant (P<0.05) dynamic CPD narrowing at C0-dens, C2-C3, and C6-C7. The narrowest dynamic CPD was observed at C0-dens during the 10 g impact and was 25.9% narrower than the corresponding neutral posture CPD. Interpretation of the present results indicate that the neurological symptomatology reported by frontal impact victims is most likely not due to cervical spinal cord compression. Cord compression due to residual spinal instability is also not likely.     

吸入麻醉药作用机制的5埃理论

在过去的20多年中，对吸入麻醉药作用机制的合理解释大量增多，同时也提出了更多目前还不能回答的问题。Eger等提出了吸入麻醉药产生对伤害性刺激无体动反应的作用靶位可能是两个相距5埃的位点的假设，简称5埃理论。现就相关问题作一综述。     

肝癌多药耐药产生与低糖环境的关系

目的探讨局部微环境低糖与肝细胞癌多药耐药性(MDR)产生的关系及影响机制。方法低糖培养HepG2细胞,应用流式细胞术Annexin V/PI法检测低糖培养的细胞在化疗药物5-氟脲嘧啶(5-Fu)作用后的凋亡情况,分别应用荧光定量聚合酶链反应(PCR)技术和Western blot技术检测低糖培养后HepG2细胞内多药耐药相关基因mdr1、MRP1、LRP的mRNA和蛋白水平的表达。结果在低糖环境下生长时间越长的HepG2细胞对5-Fu的抵抗越强,而且随着低糖培养时间的增加,5-Fu诱导的HepG2细胞的凋亡高峰延迟。低糖培养的HepG2细胞内多药耐药相关基因mdr1、MRP1、LRP在mRNA和蛋白水平的表达随低糖培养时间的延长而升高,以LRP的改变最为显著。结论肝癌生长微环境葡萄糖耐量不足也是肝癌产生MDR的原因之一。低糖可通过上调一组多药耐药相关基因的表达而诱导肝癌的多药耐药性。     

脂肪抽吸术对胰岛素敏感性及脂质代谢的影响

目的了解脂肪抽吸术对胰岛素抵抗与脂质代谢的影响,并探讨其临床意义。方法对20例接受腹部脂肪抽吸术者术前及术后2个月的血清三酰甘油、总胆固醇、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇,胰岛素敏感性进行测量并进行比较。结果术后与脂肪抽吸术前比较,术后胰岛素敏感性增强（P〈0.01）,血清总胆固醇与低密度脂蛋白胆固醇水平下降。结论腹部脂肪抽吸术在去除大量皮下脂肪的同时,对胰岛素抵抗、脂质代谢等心脑血管危险因素也有非常有益的影响。     

老年护理院医院感染病原菌及其耐药特征分析

目的探讨目前老年护理医院院内感染病原菌及其耐药特征。方法对2000年4月-2004年3月徐汇区两家老年护理院出院病人的病史进行统计分析。结果两家老年护理院共计发生医院感染939例次，医院感染率12．86％，检出病原菌284株，阳性率30．28％；病原菌以革兰阴性菌为主，占44．65％，其次为真菌、革兰阳性菌，分别为29．12％、25．92％，位于前3位的病原菌分别为其他真菌（14．36％）、白色念珠菌（12．23％）、铜绿假单胞菌（8．69％）；除嗜麦芽寡养单胞菌外，革兰阴性菌以亚胺培南最敏感，敏感率87％，对氨苄西林、阿莫西林的耐药率〉51％，对头孢哌酮、哌拉西林的耐药率〉33％；MRSA和MRSE的检出率高达86．76％和76．32％；混合感染率34．51％。结论老年护理院医院感染率高．真菌所占的比例高；细菌对抗菌药物的耐药性相当严重。     

胰岛素抵抗和脑血管病关系的研究

目的：探讨胰岛素抵抗与脑梗死、脑出血的关系，为针对胰岛素抵抗的治疗可以有效地预防脑血管疾病提供理论依据。方法：选取42例脑梗死（脑梗死组）、40例脑出血（脑出血组）及30例非脑血管病患者（对照组），分别测定空腹胰岛素（FINS）、空腹血糖（FBG），计算胰岛素敏感指数（ISI），各组间进行比较。结果：脑梗死组和脑出血组患者ISI低于对照组（P〈0.05），而FINS高于对照组（P〈0．05），FBG与对照组差异无统计学意义（P〉0．05）。结论：胰岛素抵抗可能是脑血管病的一个重要危险因素。     

Role of retinol in protecting epithelial cell damage induced by Clostridium difficile toxin A

Vitamin A (retinol), a fat-soluble vitamin, is an essential nutrient for the normal functioning of the visual system, epithelial cell integrity and growth, immunity, and reproduction. Our group has investigated the effect of high doses of oral vitamin A on early childhood diarrhea in our prospective community-based studies from Northeast Brazil and found a beneficial role in reducing the mean duration but not incidence of diarrheal episodes. In this study, we explored the role of retinol supplementation in intestinal cell lines following Clostridium difficile toxin A (TxA) challenge. C. difficile is the most common anaerobic pathogen borne with antibiotic-borne diarrhea and pseudomembranous colitis. Since retinol is critical for the integrity of tight junctions and to modulate the cell cycle, we have focused on changes in transepithelial electrical resistance (TEER) in Caco-2, a more differentiated intestinal cell line, and on models of cell proliferation, migration and viability in IEC-6 cells, an undifferentiated crypt cell line, following TxA injury. In this model, retinol therapy reduced apoptosis, improved cell migration and proliferation, and prevented the reduction in TEER, following C. difficile TxA challenge in a glutamine-free medium. These results suggest the role of retinol in protecting intestinal epithelial barrier function from C. difficile TxA enterotoxic damage.     

2003-2005年新生儿感染常见致病菌及耐药性的变迁

目的了解本地区新生儿2003至2005年感染常见致病菌的种类及耐药的现状，以指导临床合理应用抗生素。方法收集我院新生儿科2003年1月至2005年12月收治的613份体液培养阳性（痰液、血液、分泌物、胃液等标本）的患儿资料，对常见检出菌及其耐药性的变迁情况进行分析。结果共检出40种613株病原菌，以革兰阴性杆菌为主约占57．6％，而肺炎克雷伯菌和大肠埃希菌分别位于前二位，其产ESBLs菌株检出率分别为78．1％和82．6％。药敏结果显示，常见致病菌对青霉素、第一、二代头胞类抗生素、红霉素类耐药性显著增加，但对第三代头胞类抗生素如头孢曲松、头孢噻肟（凯福隆）、头孢他啶（复达欣）及B内酰胺酶抑制剂复方制剂、碳青霉烯类、万古霉素等较敏感。产ESBLs菌仅对亚胺培南及B内酰胺酶抑制剂复方制剂敏感。结论革兰阴性杆菌特别是肺炎克雷伯菌和大肠埃希菌是新生儿感染主要病原菌，产ESBLs菌比例增加应引起高度重视。碳青霉烯类、哌拉西林／三唑巴坦和头孢哌酮／舒巴坦，可作为新生儿严重医院感染经验用药，应尽量根据药敏试验调整抗生素。     

多药耐药基因转染骨髓造血细胞移植小鼠的安全性研究

目的 探讨多药耐药基因(mdrl)转染骨髓造血细胞移植后,其在体内分布和安全性.方法 骨髓造血细胞转染mdrl基因后移植入BALB/C鼠,免疫组织化学和RT.PCR观察mdrl基因在骨髓、外周血及重要脏器的表达;监测外周血白细胞变化及重要脏器病检分析其安全性.结果 P-糖蛋白(P-gP)在骨髓表达率随时间降低,各时间组差异无统计学意义(x2=3.74,P＞0.05),在外周血表达第2月最高,为(9.95±1.84)%,各时间组差异无统计学意义(x2=2.31,P＞0.05),在重要脏器无表达;移植未转染组与移植转染组外周血白细胞计数至移植60 d后,两者差异有统计学意义(t=6.173,P＜0.05),病检除肝和肾有炎性渗出和水肿病变外,其余无异常.结论 mdrl基因在骨髓和外周血有持续较高表达,在重要脏器无表达;mdrl基因转染对造血恢复及重要脏器无明显影响.