Changes of electrocardiogram and hemodynamics in response to dipyridamole: In vivo comparative analyses using anesthetized beagle dogs and microminipigs

Microminipigs are expected as a novel animal model for cardiovascular pharmacological experiments. Since inherent vulnerability of coronary circulation of microminipigs has not been characterized, we performed dipyridamole-stress test to both microminipigs and beagle dogs, and compared the results. Dipyridamole in doses of 0.056 and 0.56 mg/kg were intravenously infused over 10 min (n = 4 for each animal). Dipyridamole decreased the systolic/diastolic blood pressures and double product in dogs as well as in microminipigs; but it did not significantly alter the heart rate or the global balance between the myocardial oxygen demand and supply in either animal. While organic coronary arterial stenosis was not detected in either animal, dogs have well-developed epicardial intracoronary networks unlike microminipigs. Like in humans, dipyridamole did not affect the ST segment of microminipigs, whereas it substantially depressed that in dogs. The results indicate the onset of subendocardial ischemia by dipyridamole in dogs may be partly associated with their well-developed native coronary collateral channels. Microminipigs would be more useful to evaluate the drugs which may affect the coronary circulation in the pre-clinical study than dogs.     

胰源性区域性门静脉高压的螺旋CT表现及临床意义

胰腺肿瘤或炎性病变易侵犯或压迫脾静脉而致其阻塞,造成其引流区域血管系统形态和功能上的改变,称为胰源性区域性门静脉高压症(PSPH).①胃短静脉→胃底静脉丛→胃冠状静脉和②胃网膜静脉→胃结肠干→肠系膜上静脉是PSPH主要的两个侧支循环通道,在螺旋CT上表现出特征性的分布和走行,并在胰腺癌术前分期和评估PSPH方面具有重要临床意义.增强多排螺旋CT血管成像技术有利于连续追踪上述血管走行, 清晰显示其毗邻关系,有助于PSPH的诊断.     

基于络病理论辨析小续命汤在中风急性期的治疗价值

小续命汤历史悠久,化裁变化多样,是治疗中风的经典名方,在唐宋以前备受推崇,是"外风学说"下治疗中风的代表方剂,但随着金元时期"内风学说"的兴起,其治疗地位判若云泥,甚至到了弃而不用的地步。随着近年来络病学说的发展和完善,诸多学者从络病角度出发对中风有了新的认识,以"孙络-微血管"作为中风急性期中西两种医学体系的研究切入点,将络病作为中风急性期发病的病机关键,取得了显著成效。笔者基于络病理论对小续命汤治疗中风急性期进行初步探析,希望后世医家重新审视其治疗价值,以期为临床提供有益借鉴。     

踝关节镜下修复距腓前韧带治疗慢性踝关节不稳

目的探讨踝关节镜下改良Brostr?m法解剖修复距腓前韧带(ATFL)治疗慢性踝关节不稳的临床疗效。 方法选取2015年12月至2017年1月慢性踝关节不稳患者共12例,均采用踝关节镜辅助下改良Brostr?m法解剖修复距腓前韧带进行治疗。采用美国足踝外科学会(AOFAS)评分标准、Tegner运动水平评分及距骨倾斜角变化对手术前后疗效进行评价,随访观察并发症发生情况。治疗前后各观察指标比较采用配对t检验。 结果12例均获得15～46个月随访,平均(26±8)个月。随访期间,所有患者踝关节活动度基本达到正常水平,未出现踝关节不稳,无踝关节肿胀、疼痛等表现,末次随访AOFAS评分为(91.0±2.6)分、Tegner评分为(6.0±1.2)分,两者较术前均明显提高(t ＝10.57、12.38,均为P<0.001)。距骨倾斜角(4.5±1.0)°较术前降低(t＝7.13,P<0.001)。 结论踝关节镜下改良Brostr?m法解剖重建ATFL治疗慢性踝关节不稳,能更精准地探查韧带断端、定位韧带附着点、创伤小、疼痛轻、术后恢复快,疗效理想。     

自体与异体肌腱微创重建踝关节外侧韧带的临床对比研究

 目的 比较应用自体半腱肌腱与同种异体肌腱微创移植重建踝关节外侧韧带的临床疗效。方法 回顾性分析2006年9月至2011年6月采用微创手术治疗慢性踝关节外侧不稳患者资料。其中应用自体半腱肌腱重建踝关节外侧韧带（自体组）32例,男19例,女13例;年龄17～62岁,平均32.4岁。同期应用同种异体肌腱重建踝关节外侧韧带（异体组）36例,男22例,女14例;年龄15～67岁,平均34.2岁。两组患者均采用相同的手术方法重建距腓前韧带及跟腓韧带。结果 自体组手术时间[（85.5±11.5） min］长于异体组[（58.1±10.2）min］,发热天数异体组[（5.5±1.5）d］长于自体组[（2.5±1.2）d］。自体组23例随访（33.5±6.7）个月,异体组26例随访（28.5±6.7）个月。美国足踝外科协会（AOFAS）踝与后足评分,自体组术前（62.3±8.2）分,术后（95.1±7.5）分;异体组术前（60.2±8.4）分,术后（94.8±5.5）分。5例患者（自体组3例、异体组2例）在不平地面行走时,踝关节有残余不稳定。自体组1例患者平整地面行走踝关节有残余不稳定。自体组无一例膝部肌腱供区功能障碍。术后AOFAS评分自体组16例为优,5例为良,2例为差;异体组17例为优,5例为良,4例为差。应力位X线片示自体组距骨倾斜角平均由14.0°减少到3.8°,异体组平均由13.0°减少到3.6°;距骨前移距离自体组平均由12.3 mm减少到4.6 mm,异体组平均由11.5 mm减少到4.3 mm。结论 自体肌腱与同种异体肌腱移植重建踝关节外侧韧带的临床疗效无差异,但自体肌腱愈合时间较异体肌腱快,而异体肌腱具有损伤小,手术简便等优点。     

The morphology and clinical significance of the dorsal meningovertebra ligaments in the cervical epidural space

Background contextThe dural sac is anchored within the vertebral canal by connective tissue called meningovertebral ligaments in the epidural space. During flavectomy and laminectomy, inadvertent disruption of the dorsal meningovertebral ligaments may lead to dura laceration and cerebrospinal fluid (CSF) leaks. All the described dorsal meningovertebral ligaments were located in the lumbar region. A rare study is available about dorsal meningovertebral ligaments of the cervical spinal dura to the adjacent vertebrae.PurposeTo identify and describe the dorsal meningovertebral ligaments at each cervical level and discuss their clinical significance.Study designA dissection-based study of 22 embalmed cadavers.MethodsThe anatomy was studied in 22 whole cervical cadavers (11 females, 11males), prepared with formaldehyde, whose ages at the time of death ranged from 55 to 78 years. The vertebral canal was divided to expose the dural sac and the spinal nerve roots. At all levels of the cervical vertebra, the morphology, quantity, origin, insertion, and spatial orientation of the dorsal meningovertebral ligaments were determined and the length, width or diameter, and thickness of the ligaments were measured with vernier calipers.ResultsThe dorsal meningovertebral ligaments in the cervical region anchored the posterior dural sac to the ligamentum flavum or laminae. The number of attachment points on the ligamentum flavum was relatively larger than that on the lamina, and the occurrence rate of dorsal meningovertebral ligaments was 100% at C1–C2 and C4––C5. The thickest ligaments were observed at the C1 and C2 vertebrae. The length of the ligaments varied from 1.50 to 35.22 mm, and the orientation of the ligaments mostly was craniocaudal. The morphology of the dorsal meningovertebral ligaments was divided into four types: strip type, cord type, grid type, and thin slice type.ConclusionsIn the cervical spine, the dorsal meningovertebral ligaments exist between the posterior dural sac and the ligamentum flavum or lamina. The dorsal meningovertebral ligaments may be of clinical importance to surgeons. Dissecting the dorsal meningovertebral ligaments before the cervical flavectomy and laminectomy may be an important step in reducing postoperative dura laceration and CSF leaks, which may result in significant benefits for patients and health-care organizations.     

Collateral sensitivity of resistant MRP1-overexpressing cells to flavonoids and derivatives through GSH efflux

The multidrug resistance protein 1 (MRP1) is involved in multidrug resistance of cancer cells by mediating drug efflux out of cells, often in co-transport with glutathione (GSH). GSH efflux mediated by MRP1 can be stimulated by verapamil. In cells overexpressing MRP1, we have previously shown that verapamil induced a huge intracellular GSH depletion which triggered apoptosis of the cells. That phenomenon takes place in the more global anticancer strategy called “collateral sensitivity” and could be exploited to eradicate some chemoresistant cancer cells. Seeking alternative compounds to verapamil, we screened a library of natural flavonoids and synthetic derivatives. A large number of these compounds stimulate MRP1-mediated GSH efflux and the most active ones have been evaluated for their cytotoxic effect on MRP1-overexpressing cells versus parental cells. Interestingly, some are highly and selectively cytotoxic for MRP1-cells, leading them to apoptosis. However, some others do not exhibit any cytotoxicity while promoting a strong GSH efflux, indicating that GSH efflux is necessary but not sufficient for MRP1-cells apoptosis. In support to this hypothesis, structure activity relationships show that the absence of a hydroxyl group at position 3 of the flavonoid C ring is an absolute requirement for induction of MRP1-cells death, but is not for GSH efflux stimulation. Chrysin (compound 8) and its derivatives, compounds 11 and 22, exhibit a high selectivity toward MRP1-cells with a IC₅₀ value of 4.1 μM for compound 11 and 4.9 μM for chrysin and compound 22, making them among the best described selective killer compounds of multidrug ABC transporter-overexpressing cells.     

闭塞性冠状动脉病变侧支循环形成对急性心肌梗死患者近期预后的影响

目的探讨闭塞性冠状动脉病变侧支循环形成对急性心肌梗死(AMI)患者近期预后的影响。方法入选1996年以来行冠状动脉造影的AMI患者126例,根据有无侧支循环形成分为A组(无侧支循环组)n=69例、B组(有侧支循环组)n=57例。比较两组间院内病死率、死亡原因及存活患者心功能的差异。结果(1)B组院内病死率明显低于A组,有显著性差异(P<0.05)。(2)B组患者因心源性休克或心力衰竭而死亡的比例略低于A组,有显著性差异(P<0.05);因心脏破裂而死亡的比例明显低于A组,有显著性差异(P<0.01)。(3)存活患者出院时,B组左心室射血分数均明显高于A组,有显著性差异(P<0.05)。结论闭塞性冠状动脉病变侧支循环形成对AMI患者近期预后相对较好。