Imaging vascular function for early stage clinical trials using dynamic contrast-enhanced magnetic resonance imaging

Many therapeutic approaches to cancer affect the tumour vasculature, either indirectly or as a direct target. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has become an important means of investigating this action, both pre-clinically and in early stage clinical trials. For such trials, it is essential that the measurement process (i.e. image acquisition and analysis) can be performed effectively and with consistency among contributing centres. As the technique continues to develop in order to provide potential improvements in sensitivity and physiological relevance, there is considerable scope for between-centre variation in techniques. A workshop was convened by the Imaging Committee of the Experimental Cancer Medicine Centres (ECMC) to review the current status of DCE-MRI and to provide recommendations on how the technique can best be used for early stage trials. This review and the consequent recommendations are summarised here. Key Points ? Tumour vascular function is key to tumour development and treatment ? Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) can assess tumour vascular function ? Thus DCE-MRI with pharmacokinetic models can assess novel treatments ? Many recent developments are advancing the accuracy of and information from DCE-MRI ? Establishing common methodology across multiple centres is challenging and requires accepted guidelines.     

Effects of repetitive multiple freeze-thaw cycles on the biomechanical properties of human flexor digitorum superficialis and flexor pollicis longus tendons

Background

Deep fresh freezing is the most commonly used preservation method for allografts, which is followed by a routine procedure before application—the thawing of the grafts. This work was to explore the biomechanics effects of repetitive freezing–thawing on human tendons.

Methods

Thirty tendons (flexor digitorum superficialis and flexor pollicis longus tendons) were taken from three fresh cadavers. We assigned these tendons into six groups randomly. After the preparation and measurement of cross-sectional area, Fresh Group was tested immediately. The remaining five groups, before biomechanical testing, underwent multiple cycles (1, 2, 3, 5 or 10 cycles) of freezing (− 80 °C for 4 days) and thawing (room temperature for 6 h). Using a material-testing machine, we performed a stress-relaxation test, a creep test and a load to failure test to estimate structural and mechanical properties as well as viscoelastic changes of each group.

Findings

The results of fewer cycles (< 3) of freezing–thawing groups were similar to Fresh Group. The tendons that underwent more than five freezing–thawing cycles demonstrated a significantly smaller ultimate load, stiffness, ultimate stress and Young's modulus. Moreover, the 5 and 10 Cycle Groups showed a significant increase of elongation in creep test and a decrease of load in stress-relaxation test compared with other groups.

Interpretation

Repetitive freezing–thawing (> 5 cycles) declines the structural, mechanical and viscoelastic properties of human tendons. From our results, it is recommended that for deep-frozen preservation of tendon allografts the cycles of freezing–thawing should be less than five times with caution.     

明胶酶与角膜新生血管

目的:着重阐述明胶酶的生理特性和调节以及它在角膜新生血管生成中的作用。资料来源:应用计算机检索PUBMED1990-01/2006-01的相关文章,检索词为“gelatinase,cornea,neovascularization”并限定文章语言种类为English。同时计算机检索CNKI2000-01/2006-01的相关文章,检索词为“明胶酶,角膜,新生血管”,并限定文章语言种类为中文。资料选择:对资料进行初审,并察看每篇文献后的引文。纳入标准:①具有原创性,论点论据可靠的实验文章。②观点明确,分析全面的综述文章。排除标准:重复研究。资料提炼:共收集到30篇符合纳入标准的文献,涉及明胶酶的生理特性、调节,在角膜新生血管中的作用等方面。资料综合:①角膜新生血管形成包括毛细血管内皮下基底膜降解、内皮细胞迁移和增殖、新的血管形成和新的基底膜形成等一系列过程,角膜细胞外基质是参与这个过程的主要成分。②明胶酶是一类参与角膜细胞外基质的分化、黏附、迁移、损伤修复及组织重塑的蛋白水解酶,受基因、酶原、活化后3个水平的调节。③对实验性角膜新生血管发生中明胶酶表达的研究表明,明胶酶是新生血管发生中的重要因子,用明胶酶抑制剂可以抑制新生血管的发生。结论:明胶酶在角膜新生血管发生发展中,发挥着不可替代的作用,通过抑制其活性来阻止角膜新生血管发生,可能成为治疗新生血管相关性角膜疾病的新策略。     

产后早期乳房湿热敷按摩法配合心理暗示对产妇泌乳的影响

目的观察产妇产后早期乳房湿热敷按摩法配合心理暗示疗法对泌乳的影响。方法将300例产妇随机分为对照组144例与观察组156例,对照组产后按常规母乳喂养指导,观察组除常规母乳喂养指导外,于产后6~8 h开始,协助产妇进行乳房湿热敷按摩配合心理暗示疗法,产后进行持续的母乳喂养指导。观察两组平均泌乳时间、乳量及4个月母乳喂养情况。结果观察组较对照组泌乳始动时间明显缩短(均P<0.01),产后1周泌乳量及产后4~6个月母乳喂养率均高于对照组(均P<0.01)。结论产后早期乳房湿热敷配合心理暗示疗法,并进行持续的母乳喂养指导,可促进产妇早期泌乳,增强产妇母乳喂养信心,提高母乳坚持4~6个月以上母乳喂养率,促进母婴身心健康,产生良好的社会效益和经济效益。     

彩色多普勒超声诊断锁骨下动脉窃血综合征

目的探讨彩色多普勒超声对锁骨下动脉窃血综合征的诊断价值。方法应用彩色多普勒超声观测颈动脉、颅内外段椎动脉、锁骨下动脉、无名动脉、基底动脉及大脑后动脉的声像图特征及血流动力学的状况。结果锁骨下动脉窃血综合征主要由动脉粥样硬化和多发性大动脉炎所致,且两种原因在年龄组成、性别分布、好发部位上差异有统计学意义。锁骨下动脉窃血综合征患侧血供的代偿主要来自对侧的椎动脉。结论彩色多普勒超声对绝大多数锁骨下动脉窃血综合征可明确诊断。     

山东泰安地区两个自然村人群血脂状况调查

目的:调查了解山东泰安地区农村人群的血脂水平,为该地区农民心脑血管疾病的预防提供基础数据。方法:实验于2006-06随机选取泰安市两个自然村650人进行健康检查,男270人,女380人,年龄2～88岁。①650人均于早晨空腹采集静脉血3mL,静置凝固后,2h内分离血清,采用全自动生化分析仪常规测定患者血脂指标总胆固醇、三酰甘油水平。②总胆固醇>5.2mmol/L判定为高胆固醇血症,三酰甘油>1.7mmol/L判定为高三酰甘油血症。结果:650人全部完成血样采集与血脂指标检测。①不同性别血脂水平比较:被检人群男性三酰甘油水平显著高于女性[(1.16±1.47),(0.95±0.84)mmol/L,P<0.05];男女总胆固醇水平基本相似(P>0.05)。②不同年龄段血脂水平比较:8人因具体年龄段不祥被排除,剩余642人分为3个年龄段:2～30岁、31～50岁、51～88岁。结果31～50岁人群三酰甘油水平显著高于2～30岁人群[(1.14±1.47),(0.88±0.70)mmol/L,P<0.05],略高于51～88岁人群(P>0.05);51～88岁人群总胆固醇水平>31～50岁人群>2～30岁人群,相邻年龄段间比较差异均有显著性意义(P<0.001)。③各年龄段男女间血脂水平比较:2～30岁人群和51～88岁人群三酰甘油水平性别间差异均无显著性意义(P>0.05),但总胆固醇水平女性均显著高于男性[(2.38±1.47),(1.85±1.26)mmol/L,P<0.05;(4.48±0.92),(4.18±0.76)mmol/L,P0.01]。31～50岁人群男性三酰甘油水平显著高于女性[(1.51±2.06),(0.90±0.80)mmol/L,P<0.01],总胆固醇水平基本相似(P>0.05)。④各年龄段男女高血脂症构成比:31～50岁人群高三酰甘油血症构成比显著高于2～30岁、51～88岁人群(23.1%,5.5%,9.3%,P<0.01);随着年龄增高,各年龄段高胆固醇血症构成比逐渐升高,相邻年龄段间差异均有显著性意义(2.7%,8.6%,15.6%,P<0.01)。31～50岁人群男性高三酰甘油血症、高胆固醇血症的构成比显著高于女性(P<0.01);2～30岁、51～88岁人群男女间高血脂症的构成比基本相似(P>0.05)。结论:①山东泰安地区农村人群高三酰甘油血症,31～50岁年龄段患病率最高;高胆固醇血症患病率随年龄增长逐步上升,提示中年人健康体检尤为重要。②高脂血症应从青少年开始加大预防和保健力度,进行广泛和反复的健康教育,倡导健康的生活方式和生活行为。     

一氧化氮外源性供体L-arginine对破骨细胞骨吸收功能的影响

目的:一氧化氮在维持机体多个系统的生理功能中起重要作用,许多慢性疾病可造成一氧化氮产生减少,此时一氧化氮供体是一种必要的补充。观察一氧化氮外源性供体L-arginine对体外培养破骨细胞增殖及骨吸收功能的影响。方法:实验于2005-06/2006-05在四川大学华西医院生物治疗国家重点实验室干细胞与组织工程研究室完成。选择出生1d的清洁级SD大鼠乳鼠,采用骨髓诱导法体外培养破骨细胞,培养液内分别加入0.3,0.6,1.0g/L不同浓度的L-arginine,并以等体积三蒸水作为对照。培养7d后,以抗酒石酸酸性磷酸酶染色观察破骨细胞数目、形态,MIAS-2000图像分析仪检测骨片上骨吸收陷窝的数目和面积,并用扫描电镜观察不同浓度L-arginine对骨吸收陷窝的影响。结果:①破骨细胞的一般形态:破骨细胞较其他细胞大,形态不规则,呈油煎蛋形、长条形、腊肠形或漏斗形等,细胞内可见几个至几十个核不等。抗酒石酸酸性磷酸酶染色酶活性部分酒红色,颗粒状。②抗酒石酸酸性磷酸酶阳性细胞数:各组破骨细胞数目随着L-arginine浓度增加而减少(P<0.05)。③骨吸收陷窝的面积和数目:骨片培养7d,吸收陷窝计数的结果显示,0.3g/L以上浓度L-arginine对破骨细胞吸收功能均有明显抑制作用,并呈剂量相关性。0.3g/LL-arginine组陷窝面积为对照组的91%(P<0.05),0.6g/LL-arginine组为对照组的80%(P<0.05),1.0g/LL-arginine组为对照组的69%(P<0.01)。结论:采用骨髓诱导法培养的破骨细胞数量多、纯度高,且具有明显的骨吸收功能。L-arginine抑制破骨细胞增殖,抑制破骨细胞骨吸收功能,并呈剂量相关性。     

乳腺癌病人心理反应的相关因素及心理干预研究进展

阐述了乳腺癌病人的心理反应与心理社会因素及疾病因素相关，认知疗法、行为疗法、支持一表达式疗法、音乐疗法、教育性干预等心理干预方法对乳腺癌病人有一定的治疗效果。阐明了心理干预在乳腺癌治疗及康复中的重要性.