创伤失血后微循环多形核白细胞在毛细血管内皮附壁状态的性别差异

目的:在体实时观察创伤失血性休克复苏后微循环多形核白细胞在毛细血管后微静脉内皮的附壁是否存在性别差异,并测定多形核白细胞黏附因子CD11b的表达。方法:实验于2005-08/2006-03在解放军总医院基础所微循环室完成。①实验动物为发情前期的雌性和成年雄性SD大鼠30只,分为雄性,雌性和假手术3组,每组10只,其中假手术组雌雄各5只。②麻醉后通过放血的方法将平均动脉压降至(35±5)mmHg,并维持60min,然后在60min内用4倍于最大失血量的乳酸林格氏液进行复苏。假手术组不进行休克及液体复苏。③复苏后2h和6h在腹部正中作4cm切口,取出回盲部附近的肠系膜,显微镜下观察多形核白细胞在肠系膜毛细血管后小静脉内的附壁情况并录像。通过股动脉抽取外周血分离多形核白细胞,用流式细胞仪测定黏附分子CD11b的表达。复苏后6h将动物处死,测定肺组织髓过氧化物酶活性。结果:30只大鼠均进入结果分析。①活体微循环观测:复苏后2h,雄性组大鼠毛细血管后小静脉内多形核白细胞数量明显增多,形成附壁。复苏后6h,雄性组毛细血管后小静脉内血流出现时快时慢甚至逆流的现象,说明雄性大鼠创伤失血性休克后微循环出现紊乱。②多形核白细胞附壁的分析:复苏后2h,雌性组和假手术组的多形核白细胞附壁数低于雄性组[(1.8±0.3),(0.4±0.2),(4.2±0.9)个,P<0.05]。但6h后各组之间差异不明显。③多形核白细胞黏附分子CD11b表达的测定:复苏后2h和6h,多形核白细胞黏附分子CD11b的表达雄性组明显高于雌性组和假手术组(P<0.01),雌性组和假手术组间差异不明显。④肺组织髓过氧化物酶活性测定:休克复苏后6h,雄性及雌性肺组织髓过氧化物酶活性都与各自的假手术组相比有显著的升高(P<0.05),但雌性组升高低于雄性组(P<0.05)。结论:创伤失血性休克后雌性大鼠多形核白细胞黏附分子CD11b的表达和多形核白细胞在毛细血管后微静脉内皮的附壁数量与雄性相比明显降低,多形核白细胞在肺组织中的浸润明显减少。     

慢性乙型肝炎患者外周血髓样树突状细胞功能分析

目的:对慢性乙型肝炎患者外周血单个核细胞来源的髓样树突状细胞进行功能分析。方法:实验于2005-01/2006-07在泰山医学院完成。①髓样树突状细胞来源于2005-07/12泰山医学院附属医院传染科收治的20例慢性乙型肝炎患者,男12例,女8例,年龄21～42岁,乙型肝炎病毒标志物均为HBsAg( )、HbeAg( )、HbcAb( ),乙型肝炎病毒DNA均为阳性,3个月内均未使用抗病毒药物和免疫调节剂。诊断参照2000年西安全国病毒性肝炎会议修订的临床诊断标准,排除甲型肝炎、丙型肝炎、丁型肝炎、戊型肝炎等病毒重叠感染及其他原因引起的肝脏损害。②以14例健康供血员的髓样树突状细胞作为正常对照,男8例,女6例,年龄21～36岁。③慢性乙型肝炎患者与健康供血员各取外周血20mL,肝素抗凝,用淋巴细胞分离液分离去除红细胞和粒细胞,收集外周血单个核细胞。应用粒细胞-巨噬细胞集落刺激因子和白细胞介素4诱导培养其分化发育为髓样树突状细胞,锥虫篮染色检测细胞活力并进行细胞计数。④收集培养第10天的1×109L-1髓样树突状细胞,离心管中分别加入荧光标记抗体HLA-DR-FITC和CD86-FITC,终浓度为5mg/L,4℃标记45min,用流式细胞仪检测细胞表面表型。⑤取培养第7天的1×109L-1髓样树突状细胞,加入含体积分数为1的胎牛血清、50μg/L粒细胞-巨噬细胞集落刺激因子、10μg/L白细胞介素4、1U/L肿瘤坏死因子α的新鲜培养基继续培养,24h后收集培养上清,ELISA法检测白细胞介素10与白细胞介素12的含量。⑥培养第10天的髓样树突状细胞以30Gyγ放射线灭活后,每孔分别按髓样树突状细胞:T细胞=1∶40,1∶20,1∶10,1∶5加入到已含有纯化T细胞的96孔板中,采用3H-TdR掺入法检测髓样树突状细胞刺激同种异体T细胞增殖反应的能力。结果:①髓样树突状细胞的形态学特征及生成量:慢性乙型肝炎患者外周血单个核细胞诱导培养10d时,呈典型的髓样树突状细胞,低密度,圆形或不规则形,表面有丰富的伸长毛刺,悬浮不贴壁,与正常人群外周血单个核细胞诱导的髓样树突状细胞形态学无明显区别。锥虫篮染色结果显示两组髓样树突状细胞活力均大于95%。慢性乙型肝炎患者髓样树突状细胞数量明显低于正常人群[(3.4±0.3)×109L-1,(5.2±0.3)×109L-1,t=17.2183,P<0.01]。②髓样树突状细胞表型分析及细胞因子含量变化:与正常人群比较,慢性乙型肝炎患者髓样树突状细胞表面CD86和HLA-DR分子表达率均明显降低(t=5.4351～8.7062,P均<0.01);培养上清中白细胞介素12的含量明显降低(t=13.7208,P<0.01),白细胞介素10的含量无明显变化。③混合淋巴细胞效应:在髓样树突状细胞:T细胞=1∶5,1∶10,1∶20,1∶40时,慢性乙型肝炎患者髓样树突状细胞激活T细胞增殖的能力明显低于正常人群(t=17.7096～28.0225,P均<0.01)。结论:慢性乙型肝炎患者外周血中髓样树突状细胞数目减少、功能降低,可能是导致机体对慢性乙型肝炎病毒感染产生免疫耐受的原因之一。     

椎间盘退行性变的影响因子及其基因和组织工程结合基因治疗

目的:从各领域和不同角度探讨椎间盘退行性变的病因及其作用机制,并探索基因治疗及组织工程结合基因治疗对延缓或逆转早、中、晚期椎间盘退行性变的可能性。资料来源:应用计算机检索Pubmed数据库1998-06/2006-01有关椎间盘退行性变影响因子及生物学治疗进展的文章,检索词“intervertebral disc degeneration,nucleus pulposus,interleukin-1 beta,interleukin-6、interleukin-18,potential therapeutic model”,限定文章语言种类为English。同时检索VIP维普、CNKI中国期刊全文数据库2000-06/2006-08期间的相关文章,检索词“椎间盘退行性变、髓核、促炎因子、基因治疗”,限定文章语言种类为中文。资料选择:对资料进行初审,选取符合研究要求的有关文章找全文。纳入标准:①有关椎间盘退行性变影响因子的基础研究及临床研究。②有关基因治疗退行性变椎间盘的相关研究。③有关人工椎间盘移植的研究。排除标准:重复或类似的同一研究、个案报道等。资料提炼:共收集到123篇有关椎间盘退行性变影响因子及生物学治疗进展的文章,57篇符合研究要求(其中35篇为椎间盘退行性变影响因子基础研究方面的文献,22篇涉及基因治疗、人工椎间盘移植方面)。资料综合:①国内对椎间盘退行性变影响因子及治疗的研究:从椎间盘营养供应、细胞凋亡、基质酶活性、生物力学等方面研究与椎间盘退行性变有关的相关因素,如丝氨酸蛋白酶在退行性变椎间盘的终板中活性极高,基质金属蛋白酶3在细胞外基质成分的降解过程中起关键作用,还能通过激活其他非活性基质金属蛋白酶而对软骨基质的降解发挥间接作用。基质金属蛋白酶3表达阳性的细胞比例与MRI检查中的椎间盘退行性变程度有显著相关性,且突出型腰椎间盘中基质金属蛋白酶3表达阳性的细胞比例显著高于未突出型;;突出椎间盘组织可以诱导碱性成纤维细胞生长因子,且与突出类型、病程相关,提示碱性成纤维细胞生长因子在腰椎间盘组织退行性变、自发性吸收中有重要的促进作用等。并探讨相关基因(成骨蛋白1、骨形态发生蛋白7)在延缓或逆转椎间盘退行性变治疗上的可行性。②国外对椎间盘退行性变影响因子及治疗的研究:从以上几方面研究椎间盘退行性变的因素及机制,如胰岛素样生长因子和血小板来源的生长因子均可降低椎间盘细胞的凋亡指数,为该病的防治提供了新的思路;;白细胞介素1使椎间盘纤维环细胞产生的前列腺素E2和磷脂酶A2增加,减少纤维环中总的蛋白多糖含量;;最近研究发现白细胞介素18是强有力的致炎因子之一,在退行性变的关节软骨及椎间盘软骨终板呈一定表达,遂被认为在椎间盘退行性变中发挥重要作用,但少见报道。同时探索用腺相关病毒体外转染人椎间盘细胞,体内转染兔椎间盘细胞,并证实自体同源椎间盘细胞、同源软骨、同种异体的完整椎间盘或活性椎间盘细胞移植可以延缓椎间盘退行性变,又以腺病毒转染SV40基因的方法成功构建了永生化的人髓核细胞株,可作为组织工程椎间盘的种子细胞。③国内外关于椎间盘退行性变影响因子及治疗研究的展望:提供更多的临床样本,探索创新出更多、更细致的思路来综合研究椎间盘退行性变的可能机制和根本治疗方法。结论:椎间盘退行性变的确切机制目前尚不清楚,其生物学治疗仍处于动物实验研究阶段,只有通过大量的临床样本及动物试验,并探求出更加深入细致的研究方法,尤其是最热点及最有前途的组织工程方法,才能为在最终应用于人椎间盘退行性变的治疗上提供切实可靠的治疗手段。     

Modeling the growth of Yersinia enterocolitica in donated blood

BACKGROUND: Sepsis and death subsequent to the transfusion of blood containing Yersinia enterocolitica is an increasing problem. The organisms probably originate from bacteremia in the donor and can subsequently multiply at low temperature. STUDY DESIGN AND METHODS: Reported here are experiments with a strain of Y. enterocolitica associated with a case of transfusion-associated bacteremia. RESULTS: It was found that the rapid early killing of Y. enterocolitica injected into donated blood does not require viable phagocytes and can be explained by complement-mediated killing. Complement resistance in Y. enterocolitica is known to be plasmid-coded. It is expressed at 37 degrees C, but not at 20 degrees C, and is favored by calcium-deficient culture media. Y. enterocolitica organisms induced to express complement resistance were still killed in donated blood, though the initial rate was slower. Such organisms multiplied in plasma at 37 degrees C, but were killed after 6 hours of incubation at 20 degrees C, presumably because complement resistance genes are switched off at this temperature. CONCLUSION: This experiment is thought to reflect the natural history of Y. enterocolitica contamination of blood, in which complement-resistant organisms in the donor blood encounter lower temperatures after donation. These observations suggest that the practice of plasma depletion may have contributed to the increased incidence of mortality due to Y. enterocolitica contamination of donated blood.     

Wait times for gastroenterology consultation in Canada: The patients�� perspective

Long wait times for health care have become a significant issue in Canada. As part of the Canadian Association of Gastroenterology’s Human Resource initiative, a questionnaire was developed to survey patients regarding wait times for initial gastroenterology consultation and its impact. A total of 916 patients in six cities from across Canada completed the questionnaire at the time of initial consultation. Self-reported wait times varied widely, with 26.8% of respondents reporting waiting less than two weeks, 52.4% less than one month, 77.1% less than three months, 12.5% reported waiting longer than six months and 3.6% longer than one year. One-third of patients believed their wait time was too long, with 9% rating their wait time as ‘far too long’; 96.4% believed that maximal wait time should be less than three months, 78.9% believed it should be less than one month and 40.3% believed it should be less than two weeks. Of those working or attending school, 22.6% reported missing at least one day of work or school because of their symptoms in the month before their appointment, and 9.0% reported missing five or more days in the preceding month. A total of 20.2% of respondents reported being very worried about having a serious disease (ie, scored 6 or higher on 7-point Likert scale), and 17.6% and 14.8%, respectively, reported that their symptoms caused major impairment of social functioning and with the activities of daily living. These data suggest that a significant proportion of Canadians with digestive problems are not satisfied with their wait time for gastroenterology consultation. Furthermore, while awaiting consultation, many patients experience an impaired quality of life because of their gastrointestinal symptoms.     

Carpal avascular necrosis: MR imaging

The authors evaluated the use of magnetic resonance (MR) imaging in diagnosis of avascular necrosis (AVN) of carpal bones by examining 21 patients with wrist pain and two healthy volunteers. MR images were compared with conventional radiographs in every case and with bone scintigrams in 18 cases. MR imaging was slightly less sensitive than bone scintigraphy in depicting AVN, but in patients who were imaged with long repetition time (TR)/long echo time (TE) sequences in addition to short TR/short TE sequences, MR imaging was found to be more specific. While the authors believe that bone scintigraphy remains the screening test of choice for patients with wrist pain and normal plain radiographs, MR imaging promises to add significant diagnostic information in cases in which bone scans are abnormal.     

Bone and soft-tissue lesions: diagnosis with combined H-1 MR imaging and P-31 MR spectroscopy

The feasibility of combined magnetic resonance (MR) imaging and surface coil phosphorus-31 MR spectroscopy at 1.5 T was examined in a clinical study of 34 patients before biopsy of bone or soft-tissue lesions of the extremity and trunk. The results confirmed the inability of MR imaging alone to distinguish most benign lesions from malignant ones. Malignant lesions were distinguished from benign lesions on the basis of significantly higher mean peak ratios of phosphomonoester (PME) to beta-nucleoside triphosphate (NTP) and of phosphodiester to NTP, a significantly lower mean peak area ratio of phosphocreatine to NTP, and a higher mean pH. The diagnostic performance of the PME/NTP peak area ratio is characterized by a sensitivity (true-positive fraction) of 1.00 and a specificity (true-negative fraction) of 0.93. This study provided preliminary evidence that P-31 MR spectroscopy may be used to improve diagnostic specificity in bone and soft-tissue lesions.     

Fitness testing and career progression in AFL football

Relationships between fitness testing and career progression in the Australian Football League (AFL) are under-explored. This study investigated relationships between anthropometric and fitness tests conducted at the annual AFL National Draft Camp and subsequent career progression of players. A total of 283 players was tested over three consecutive camps (1999-2001). The anthropometric and fitness measures were: height, mass, sum of skinfolds, 20-m sprint test, vertical jump (standing and bilateral running), agility run and a multi-stage incremental shuttle run. The five outcome variables were: drafted (yes/no), AFL debut (yes/no), number of AFL games played to the end of 2003, and subjective ratings of career potential and career value (5-point scale). Of 205 players (72%) subsequently drafted, 166 (59%) eventually made their AFL debut. Players drafted to AFL clubs were faster over 5 m, 10 m and 20 m, ran further in the shuttle run and ran marginally faster in the agility test than players not drafted. Multi-regression analysis showed small to moderate correlations (r = 0.27-0.31) between the designated outcome variables and selected fitness tests: 20-m sprint time (faster), agility run test (faster), and running vertical jump (higher absolute height and smaller difference between left and ride sides). Regression analysis for the standing vertical jump relative to standing reach height showed a counterintuitive negative correlation with positive outcomes, possibly reflecting non-compliance with testing procedures by the less successful athletes. We conclude that the 20-m sprint, jump, agility and shuttle run tests have a small but important association with career progression of AFL footballers.