双荧光素酶报告基因技术验证miR-31对LATS2的靶向调控作用

目的通过双荧光素酶报告基因技术验证miR-31对大肿瘤抑制因子2(LATS2)的靶向调控作用,观察miR-31在心肌细胞肥大过程中的可能影响。方法运用Targetscan软件预测大鼠miR-31对LATS2的靶向调控作用;以双荧光素酶报告质粒为工具载体,分别插入人工合成的大鼠LATS2基因野生型3′UTR(LATS2-3′UTR-WT)及突变型3′UTR(LATS2-3′UTR-MU)片段,构建LATS2-3′UTR-WT及LATS2-3′UTR-MU双荧光素酶报告质粒;重组双荧光素酶报告质粒分别与miR-31过表达质粒共转染293T细胞,检测荧光素酶活性并分析miR-31对LATS2的靶向调控作用;血管紧张素Ⅱ(AngⅡ)诱导体外心肌细胞肥大模型,RT-qPCR检测miR-31、LATS2及心肌细胞肥大基因心房钠尿肽(ANP)、β-肌球蛋白重链(β-MHC)的表达,F肌动蛋白荧光探针观察心肌细胞形态变化。结果 Targetscan软件预测结果显示,大鼠miR-31与LATS2基因3′UTR存在互补结合位点;经酶切及基因测序鉴定,成功构建LATS2-3′UTR-WT及LATS2-3′UTR-MU双荧光素酶报告质粒;与LATS2-3′UTR-MU+miR-31组相比,LATS2-3′UTR-NC+miRNA-31组荧光素酶活性无明显变化(0.98±0.03 vs.1.00±0.03,P0.05),而LATS2-3′UTR-MT+miR-31组与LATS2-3′UTR-NC+miR-31组相比,荧光素酶活性显著降低(0.74±0.02 vs.1.00±0.03,P0.01);AngⅡ诱导48h后可检测到心肌细胞肥大基因ANP(P0.01)及β-MHC表达上调(P0.05),心肌细胞肥大过程中miR-31表达显著上调(P0.01),LATS2基因明显下调(P0.05),96h后心肌细胞表面积明显增大。结论 miR-31可通过与LATS2基因3′UTR互补结合实现其对LATS2靶向调控作用,miR-31靶向作用LATS2可能参与调控心肌细胞的肥大。     

过表达p53对机械负荷导致的心肌细胞肥大反应的影响

目的:观察心肌细胞内过表达p53对机械牵张引起的心肌细胞肥大反应的影响.方法:使用大鼠乳鼠来源的心肌细胞,对贴壁培养在硅胶培养皿内的心肌细胞进行0 min、5 min、10 min、30 min、1 h和2 h的机械牵张.以Western blot法检测心肌细胞肥大反应相关蛋白激酶细胞外信号调节激酶1/2(ERK1/2)在不同时间牵张后磷酸化水平变化的时间特点;将含p53基因的重组腺病毒载体(p53-Adv)转染心肌细胞使之高表达p53蛋白.再行同样的不同时间的机械牵张,观察磷酸化ERK1/2表达的时间变化特点;最后将两部分结果对比以明确p53过表达对机械牵张后ERK1/2磷酸化变化的影响.结果:未行p53-Adv转染时5 min牵张组磷酸化ERK1/2表达比0 min牵张组明显升高(P<0.05).并且随着牵张时间的延长ERK1/2磷酸化水平逐步增高;而p53-Adv转染后,5 min牵张组磷酸化ERK1/2表达较0 min牵张组仍增加(P<0.05),但更长时间牵张组较0 min牵张组ERK1/2磷酸化水平不升反降(P<0.05),以2 h组最低(P<0.05).结论:心肌细胞内过表达p53后,虽然不影响短期牵张(5 min)的ERK1/2磷酸化水平的升高,但明显抑制更长时间牵张后的磷酸化ERK一表达,提示心肌细胞内的p53对机械负荷后晚期的心肌肥厚反应有抑制作用,p53可能与心肌肥厚由代偿期向失代偿期的转化有关.     

PAK1-nNOS-NO信号通路在有氧运动减轻压力负荷小鼠心肌肥厚中的作用及其机制

目的:有氧运动减轻压力负荷小鼠心肌肥厚中PAK1-nNOS-NO发挥的作用及机制。方法:将C57BL/6小鼠通过主动脉缩窄术(transverse aortic constriction,TAC)建立小鼠压力负荷模型,通过游泳对其进行有氧运动干预。将小鼠随机分为5组:假手术(SHAM),SHAM+有氧运动(SHAM+E),TAC,TAC+有氧运动(TAC+E)和TAC+有氧运动+IPA-3(TAC+E+I)组。通过小鼠心脏重量指数(heart weight to body weight ratio,HW/BW)变化和心脏结构变化评价心脏肥大程度,心肌组织麦胚凝集素染色评价心肌细胞肥大程度;ELASA试剂盒检测心肌组织NO水平,MDA含量和SOD活性。Western印迹检测p-PAK1,eNOS,p-eNOS Ser114,nNOS和p-nNOS Ser1412蛋白表达水平。结果:随着术后时间的延长,与SHAM组相比,TAC组HW/BW、左室质量(left ventricular mass,LVM)、左室后壁厚度(left ventricular posterior wall thickness,LVPWS)以及室间隔厚度(interventricular septal thickness,IVSS)显著增加,心肌细胞肥大,MDA含量增高,SOD活性降低,但p-PAK1蛋白含量和NO水平却显著降低。有氧运动后,TAC+E组与TAC组相比HW/BW和LVM降低,心肌细胞肥大程度减轻,组织MDA含量减少,SOD活性升高,p-PAK1表达增加,NO水平升高。而给予PAK1抑制剂IPA-3后,与TAC+E组相比,运动训练对心肌肥厚的作用减弱。TAC小鼠eNOS和nNOS表达增高,p-nNOS Ser1412和p-eNOS Ser114表达降低。运动训练可上调nNOS,p-nNOS Ser1412和p-eNOS Ser114表达;而注射IPA-3后,TAC+E+I小鼠与TAC+E小鼠相比,nNOS和p-nNOS Ser1412表达降低,eNOS和p-eNOS Ser114蛋白表达水平无明显改变。结论:PAK1-nNOSNO信号可能是介导有氧运动减轻压力负荷小鼠心肌肥厚作用的关键信号通路。     

miR-142-3p靶向调控mll-af4融合基因的实验研究

本研究探讨mll-af4融合基因的表观遗传学调控机制,以筛选靶向调控mll-af4融合基因的microRNA。利用Targetscan在线分析软件预测特异性靶向mllaf4基因3′端非翻译区域（3′-untranslated region,3′UTR）的microRNA,采用PCR方法从1例健康供者DNA中扩增mll-af4基因3′UTR序列,插入经EcoRI和PstI双酶切的荧光素酶报告载体pGL3-M,采用脂质体SuperFect包裹荧光素酶重组质粒及microRNA表达质粒转染293T细胞,应用双荧光素酶检测试剂盒测定荧光素酶活性。miR-142-3p mimics以脂质体Hiperfect转染至RS4;11细胞,选用实时定量PCR及Western blot检测mll-af4 mRNA及蛋白的表达。结果表明,成功构建了含有1935bp、2104bp和1371bp的mll-af4基因3′UTR序列的荧光素酶报告重组质粒pGL3-AF4-3′UTR,并通过酶切及基因测序方法鉴定得到证实。荧光素酶报告实验提示,miR-142组荧光素酶活性明显低于对照组。RS4;11细胞中过表达miR-142-3p可以明显下调MLL-AF4融合蛋白及mRNA表达。结论：miR-142-3p通过靶向结合mll-af4基因3′UTR的结合位点特异调控mll-af4基因表达。     

急性机械牵张对正常和肥厚心脏p38激酶活性的影响

目的:探讨急性机械牵张对正常心脏和压力超负荷致心肌肥厚心脏的p38激酶活性的影响.方法:40只雌性SD大鼠随机分成4组各10只.其中C、D组行腹主动脉环扎术,造成左心室肥厚的动物模型.用Westernblot方法测定各组大鼠左心室肌的p38激酶活性.结果:术后4周C、D组大鼠有明显的心肌肥厚,心功能处于代偿期.A组即假手术不行急性机械牵张的大鼠左心室肌未见明显的p38激酶活化;而B组即假手术行急性机械牵张、C组术后不行急性机械牵张、D组术后行急性机械牵张的大鼠左心室肌中p38激酶均发生明显活化(P＜0.01);其中与C组比较D组p38激酶并未进一步活化.结论:p38激酶信号转导途径是机械牵张导致心肌肥厚的重要环节;但在已肥厚的心脏,p38激酶活性的改变可能能够阻止心脏再受额外刺激而发展为失代偿性肥厚.     

人乳腺癌上皮细胞miR-217对DNMT1调控作用的研究

目的 验证在乳腺癌上皮细胞系中,miR-217通过直接作用于DNMT1 3′UTR调控DNMT1表达,为后期动物实验和临床试验提供实验基础.方法 利用瞬时转染技术,在对应细胞系中,过表达、抑制miR-217,Western blot检测各实验组中DNMT1蛋白表达,并用含有miR-217野生型及突变型识别位点的DNMT1 3′UTR载体质粒分别转染293T细胞,检测相对荧光素酶活性改变.结果 过表达miR-217,DNMT1表达下降;抑制miR-217,DNMT1表达增高;双荧光素酶检测实验,DNMT1-UTR-WT的相对荧光素酶活性显著低于DNMT1-UTR-MUT,差异有统计学意义（P〈0.05）.结论 在乳腺癌上皮细胞系中,miR-217对DNMT1表达具有调控作用,且miR-217通过直接作用于DNMT1 3′UTR调控DNMT1表达.     

小鼠心肌内转基因后压力超负荷模型的实验研究

目的::探索在短时间内建立小鼠心肌内转基因后压力超负荷模型,为深入研究心脏肥大的分子机制提供可靠的实验对象。方法:雄性C57BL/6小鼠随机分为升主动脉缩窄组(手术组)和同期假手术组(对照组),手术组根据暂时阻断主动脉血流5s、10s、20s、30s同时左心腔内分别注射Ad-LacZ或PBS后又分为LacZ组和PBS组,观察术后4周不同时间小鼠体重、颈动脉血压和心脏超声等变化HE染色和X-gal染色分别观察心肌肥厚情况和基因转染情况。结果:手术成活率88.8%。升主动脉缩窄小鼠的血压较对照组明显升高。缩窄术后2周心肌明显肥厚,4周时出现失代偿性心力衰竭。X-gal染色显示阻断血流5s以上心脏有蓝染,但10s、20s、30s之间无明显区别。结论:该方法简单有效,重复性好,可在短时间内建立小鼠心肌内转基因和压力超负荷心肌肥厚模型,为心脏肥大的深入研究提供可靠的实验对象。左心室心腔直接注射转染Ad-LacZ基因同时阻断升主动脉血流10s以上可以使目的基因有较好的表达。     

Dysbindin转基因小鼠心肌肥厚模型中基因变化

目的 探讨Dysbindin转基因小鼠不同心肌肥厚模型心肌肥厚标志基因的表达。方法 构建cTNT-Dysbindin-IRES-EGFP-polyA质粒,受精卵原核显微注射C57BL/6小鼠,建立Dysbindin转基因小鼠。采用异丙肾上腺素（Isoproternol,ISO）和胸主动脉缩窄（Thoracic aorta constriction,TAC）诱导心肌肥厚。造模结束,称取小鼠体重、心脏重量,计算心脏重量指数（HW/BW）;采用qRT-PCR检测心肌肥厚标志基因表达。结果 应用PCR扩增产物和GFP阳性验证Dysbindin转基因小鼠特异性表达在心肌。ISO组和TAC组转基因小鼠和野生型小鼠的HW/BW和心肌肥厚标志基因升高,与野生型小鼠比较,转基因小鼠心房利钠肽（ANP）和-肌球蛋白重链（-MHC）基因表达水平降低。结论 Dysbindin转基因小鼠对于ISO和TAC诱导心肌肥厚有减轻作用,ANP和-MHC降低优于脑钠钛（BNP）。     

miR-34a靶向调控HDAC1基因对急性髓系白血病细胞凋亡的影响

目的:探讨急性髓系白血病细胞中miR-34a对HDAC1的调控作用以及对细胞凋亡的影响。方法:将miR-34a mimics、miR-34a inhibitor、miR-34a scramble转染到HL-60细胞中,采用CCK8试验和流式细胞术分别检测miR-34a不同表达水平对HL-60细胞增殖和凋亡的影响。应用Western blot检测miR-34a表达改变后HDAC1蛋白表达水平。构建含HDAC1 3′UTR的双荧光素酶报告载体,应用双荧光素酶报告实验验证miR-34a与HDAC1的作用位点。构建不含HDAC1 3′UTR的表达载体,应用回复实验验证miR-34a与HDAC1的相互作用。结果:miR-34a过表达可导致HL-60细胞的增殖抑制、凋亡率增加。生物信息学分析表明,HDAC1是miR-34a的靶基因;Western blot结果显示,miR-34a高表达可下调HDAC1蛋白表达,双荧光素酶实验和回复实验显示,miR-34a可作用于HDAC1 3′UTR区,调理其表达。结论:miR-34a促进HL-60细胞凋亡,其作用可能与其对HDAC1表达调控有关。     

L-精氨酸对心肌肥厚模型大鼠细胞凋亡的干预

目的探讨细胞凋亡在大鼠心肌肥厚形成中的作用及L精氨酸(LArg)对这一过程的影响。方法36只大鼠随机分为对照组、模型组和给药组,制作压力超负荷性心肌肥厚模型,观察各组大鼠的动脉收缩压(SBP)和心脏指数,采用分光光度法和流式细胞术测定一氧化氮(NO)含量、超氧化物歧化酶(SOD)活性和心肌细胞凋亡率。结果与对照组相比,模型组大鼠SBP、心脏指数与心肌细胞凋亡率升高,SOD活性与NO水平下降;与模型组相比,给药组大鼠SBP、心脏指数与心肌细胞凋亡率降低,SOD活性与NO水平升高。结论细胞凋亡是压力超负荷性心肌肥厚发生过程中导致心肌细胞数量减少的重要原因;LArg可诱导NO生成增多,并通过增强SOD的活性抑制心肌细胞凋亡的发生。     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

Clinical Pharmacokinetics of Morphine

Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.     

手转胎头术失败的原因与分娩结局临床分析

目的 探讨手转胎头术失败的原因与分娩结局.方法 选择2008年1月至2010年12月于我院住院分娩的持续性枕横位、枕后位产妇198例,根据行手转胎头术后结果分为成功组126例、失败组72例.比较两组分娩结局,对比分析失败原因.结果 失败组胎儿体质量≥3500 g的发生率[76.4％(55/72)]明显高于成功组[31.7％(40/126)],差异有统计学意义(x2=30.177,P=0.001)、失败组宫缩乏力发生率[58.3％(42/72)]高于成功组[38.1％ (48/126)],差异有统计学意义(x2=7.569,P=0.006)、失败组骨盆临界或轻度狭窄发生率[38.9％ (28/72)]高于成功组[23.8％(30/126)],差异有统计学意义(x2 =5.030,P=0.002)、失败组手转胎头时机不当(宫口开大＜6 cm、胎头位于坐骨棘上及宫口开大8～10 cm、胎头位于坐骨棘下≥2 cm)发生率[61.1％(44/72)]高于成功组[38.9％(49/126)],差异有统计学意义(x2=9.084,P=0.003).失败组母儿并发症(产后出血、产褥病率、胎儿窘迫、新生儿窒息)发生率高于成功组(x2 =9.586,P=0.002、x2=9.334,P=0.002、x2=5.910,P=0.015、x2=5.240,P=0.022)、失败组剖宫产发生率[72.2％(52/72)]明显高于成功组[34.1 ％(43/126),x2=26.641,P=0.001)].结论 手转胎头术能使难产变顺产,降低剖宫产率,减少母儿并发症,但须积极预防、处理导致手转胎头术失败的原因,对矫正失败后继续矫正及试产应慎重.     

Evidence-Based Pain Management and Palliative Care in Issue Four for 2009 of The Cochrane Library

ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly. Issue 4 for 2009 contains 4027 complete reviews, 1906 protocols for reviews in production, and 11447 one-page summaries of systematic reviews published in the general medical literature. In addition, there are citations of 600,000 randomized controlled trials, and 12,200 cited papers in the Cochrane methodology register. The health technology assessment database contains over 7500 citations. This edition of the Library contains 90 new reviews, of which 19 have potential relevance for practitioners in pain and palliative medicine.     

Wie zuverlässig sind Angaben zu nichtentzündlichen ausgedehnten Schmerzen?

ZusammenfassungFragestellung Es wurde geprüft, wie sich der Differenziertheitsgrad zweier Schmerzmessmethoden auf Angaben zur Ausgedehntheit klinischer Schmerzen auswirkt. Zugleich wurde der Referenzzeitraum variiert, über den die Patienten berichten sollten.Methode Erfasst wurde der Einfluss zu Lasten der Befragungsdifferenziertheit durch den Vergleich zweier Körperschema-Bildvorlagen. Drei Referenzzeiträume (Schmerz aktuell, letzte Woche, letztes halbes Jahr) wurden vorgegeben.Ergebnisse Patienten mit ausgedehnten Schmerzen gaben bei differenzierter Befragung um so mehr Schmerzen an, je weiter die Schmerzen zurück lagen und je größer der Berichtszeitraum war. Patienten mit gelenknahen Schmerzen gaben bei hoch differenzierter Befragung weniger ausgedehnte Schmerzen in der Vergangenheit an als bei globaler Einschätzung. Patienten mit Rückenschmerzen berichteten bei differenzierter Befragung zum aktuellen Schmerz über weniger ausgedehnte Schmerzen als bei globaler Befragung.Schlussfolgerung Die Angaben zur Schmerzausdehnung variieren vor allem bei Patienten mit ausgedehnten Schmerzen in Abhängigkeit von der Differenziertheit der Befragung. In diesen Fällen ist die Wahrscheinlichkeit erhöht, dass sich die Beschwerdesymptomatik zumindest teilweise erst in der Reaktion auf die situativen Befragungsbedingungen konstituiert und daher nicht auf andere Befragungsbedingungen generalisiert werden kann.