失神经固定制动不同时间大鼠降钙素基因相关肽水平变化对骨密度的影响*

背景：大量研究认为降钙素基因相关肽具有刺激成骨、增加骨量,促进神经再生等诸多功能,然而不同制动后降钙素基因相关肽的变化规律及对骨质疏松形成过程中的作用和机制至今仍不十分清楚。 目的：观察失神经固定后神经肽物质对大鼠骨密度的影响及其可能机制。 设计、时间及地点：随机对照动物实验,于2006-09/11在湘南学院附属医院完成。 材料：10周龄SD雄性大鼠96只,体质量220~250 g,用于制备失神经支配模型。 方法：96只SD大鼠按数字表法随机分为3批,每批4组,每组8只。失神经支配组：大鼠麻醉后,先于俯卧位行两侧后肢股外侧切口,于股骨转子水平切断双侧坐骨神经;再置大鼠于仰卧位,行两侧股正中纵切口,于腹股沟韧带水平切断大鼠两侧股神经,远端游离5 mm,缝合切口。固定组：大鼠固定与失神经支配手术同时进行,麻醉后应用管型石膏分别固定1,10,30,60 d。对照组行假手术,即在造模过程中仅暴露神经,然后缝合伤口。 主要观察指标：实验期间大鼠的一般情况;造模后1,10,30,60 d各组大鼠胫骨骨密度和降钙素基因相关肽的变化及降钙素基因相关肽水平与骨密度水平相关性。 结果：96只SD大鼠均进入结果分析。①大鼠失神经造模后两后肢无主动屈伸功能,前进时以臀部肌群帮助行走,后退时靠腰腹部肌群收缩代偿,活动量显著减少。固定组大鼠精神好,活动时后肢拖地。对照组大鼠无明显异常。②造模后10,30,60 d失神经支配组大鼠胫骨降钙素基因相关肽的表达低于对照组(P < 0.05~0.01);而固定组仅造模后30 d时与对照组之间存在显著性差异(P < 0.05)。造模后10,60 d固定组高于失神经支配组(P < 0.05~0.01)。③与对照组相比,失神经支配组、固定组造模后30,60 d骨密度降低(P < 0.05~0.01);失神经支配组和固定组造模30 d时骨密度开始下降,60 d后下降明显,组内比较差异有显著性意义(P < 0.05~0.01)。④失神经后降钙素基因相关肽与骨密度水平变化高度相关(P < 0.05);而固定后降钙素基因相关肽与骨密度水平变化相关程度不高。 结论：神经的完整性是降钙素基因相关肽水平维持正常的关键,动态观察降钙素基因相关肽水平变化,可在一定程度上预测失神经性骨质疏松形成、发展。     

大鼠失神经支配后股骨密度变化的实验研究

目的　探讨大鼠失神经后骨密度变化的可能原因 ,以及NGF注射、电刺激和被动运动等治疗的应用价值 ,并为临床预防神经源性骨质疏松的治疗提供实验依据。方法　切断SD雄性大鼠坐骨神经和股神经 ,造成失神经支配大鼠模型 ,利用NOR LAND、XR 36型双能骨密度检测仪进行骨量测定。结果　大鼠失神经支配可引起骨密度的改变 ,通过NGF注射、电刺激和被动运动等治疗可减缓失神经大鼠的骨量下降 ,而失神经肢体的固定则加重了骨量的降低。结论　通过大鼠失神经后的骨密度变化 ,说明股骨密度在失神经支配后受多种因素的调控 ,其中力学因素是其首要和主要因素 ,同时大鼠失神经支配后 ,促进神经功能的重建以及维持神经再支配的生物学环境的稳定将有利于防止骨量的下降和骨质疏松的发生。     

大鼠失神经支配后股骨密度变化的实验研究

目的 探讨大鼠失神经后骨密度变化的可能原因，以及NGF注射、电刺激和被动运动等治疗的应用价值，并为临床预防神经源性骨质疏松的治疗提供实验依据。方法 切断SD雄性大鼠坐骨神经和股神经，造成失神经支配大鼠模型，利用NORLAND、XR-36型双能骨密度检测仪进行骨量测定。结果 大鼠失神经支配可引起骨密度的改变，通过NGF注射、电刺激和被动运动等治疗可减缓失神经大鼠的骨量下降，而失神经肢体的固定则加重了骨量的降低。结论 通过大鼠失神经后的骨密度变化，说明股骨密度在失神经支配后受多种因素的调控，其中力学因素是其首要和主要因素，同时大鼠失神经支配后，促进神经功能的重建以及维持神经再支配的生物学环境的稳定将有利于防止骨量的下降和骨质疏松的发生。     

成肌调节因子Myf-5在失神经骨骼肌萎缩不同时段的表达

背景：成肌调节因子Myf-5是参与肌肉发生过程分子调控、启动和维持骨骼肌细胞生长发育的重要基因,可能与失神经骨骼肌萎缩的发生有关。 目的：观察不同部位、不同时段骨骼肌失神经支配后成肌调节因子Myf-5基因的表达情况。 设计、时间及地点：随机对照动物实验,于2008-03/04在山西医科大学完成。 材料：选择健康8周龄雄性SD大鼠24只,随机分成4组,即假手术组(有神经支配)、去神经2 d组、去神经7 d组、去神经28 d组,每组6只。 方法：假手术组不切断坐骨神经,仅做假手术。去神经组右下肢后部中段切断坐骨神经1 cm以上,分别于去神经第2,7,28天用脊椎脱臼法处死大鼠,分离出右小腿的胫骨前肌、比目鱼肌、腓肠肌、跖肌标本。 主要观察指标：用反转录-聚合酶链反应技术检测各组肌肉Myf5 mRNA表达情况,抗Myf-5 多克隆抗体免疫组织化学染色(ABC 法),测量灰度值。 结果：去神经骨骼肌早期,Myf-5的mRNA在去神经支配后第2,7,28天均表达上调(P < 0.05)。Myf-5 抗体阳性染色细胞核数在SD大鼠骨骼肌失神经28 d时的肌卫星细胞中最多。 结论：Myf-5在大鼠失神经骨骼肌萎缩早期不同肌肉表达均为上调。大鼠骨骼肌失神经支配后早期肌卫星细胞中Myf-5表达上调。     

经皮电刺激大鼠骨骼肌失神经肌萎缩时成肌调节因子基因的表达

背景：在去神经早期大鼠骨骼肌成肌调节因子(MyoD)表达明显上调,有明显延缓骨骼肌肌萎缩的作用。临床实验证实电刺激是治疗失神经肌萎缩的有效方法。尚未有实验证实电刺激对失神经肌萎缩MyoD表达的影响。 目的：验证电刺激对大鼠骨骼肌MyoD基因表达的影响。 设计、时间及地点：随机对照动物实验,于2008-07/11在山西医科大学动物实验中心完成。 材料：健康的SD大鼠36只,雌雄不限。随机分成3组,即空白对照组、去神经组、电刺激组,每组12只。 方法：空白对照组不做任何处理;去神经组和电刺激组大鼠制作右侧坐骨神经离断,腓肠肌失神经支配模型。用电刺激对电刺激组进行刺激,1次/d,30 min/次。分别于去神经第2,7,14,28天,处死大鼠,取小腿的腓肠肌肉标本。 主要观察指标：用反转录聚合酶链式反应技术检测MyoD mRNA的表达变化,免疫组织化学检测MyoD蛋白表达的变化。 结果：在去神经支配后第2,7,14,28天,去神经组和电刺激组标本中MyoDmRNA和蛋白含量表达上调,与空白对照组比较差异有显著性意义(P < 0.05),电刺激组表达高于去神经组(P < 0.05)。 结论：通过电刺激可以上调大鼠腓肠肌失神经模型MyoD的表达,说明电刺激是延缓骨骼失神经肌萎缩的有效方法。     

带神经血管肌束分点植入后失神经肌肉形态学改变

背景：失神经支配的肌萎缩一直是临床治疗的难点,目前仍没有突破性的研究成果。 目的：观察带神经血管的肌束分点植入后对失神经支配肌肉形态学影响，探求一种失神经支配肌萎缩研究的新思路。 设计、时间及地点：同体对照动物实验，于2006-07/2007-12在南京鼓楼医院手外科完成。 材料：清洁级健康Wistar大白鼠30只，雌雄不限，体质量250 g左右。 方法：建立大鼠双下肢腓肠肌外侧头失神经支配模型。其中右侧在腓肠肌外侧头肌腹中远1/3处做两切口，用比目鱼肌作成带神经血管肌束，分点植入失神经支配肌肉内，作为实验组。左侧只切断腓肠肌外侧头肌支作为对照组。分别于术后4，8，12周取材。 主要观察指标：观察肌肉外观、超微结构变化，测定肌纤维周径及截面积、胶原纤维含量。 结果：①实验侧的腓肠肌饱满、有弹性、色泽好、切之出血多。对照组肌肉萎缩变细、色泽灰白、切之出血少。②各时间点实验组肌细胞周长和肌肉纤维横截面积测量值大于对照组（P均< 0.01）；胶原纤维含量低于对照组（P < 0.01）。③实验组细胞核基本正常，肌膜光滑，肌纤维间距小，线粒体数量多、嵴完整。对照组肌肉细胞核变形、空泡化，肌膜呈乳突样改变，肌纤维明显变细，间距增大，线粒体数量少、出现空泡化及絮状化，脂滴增多。 结论：带神经血管肌束分点植入法是一种延缓失神经支配肌肉萎缩的有效方法。     

蛋白酶体抑制剂MG-132作用下失神经骨骼肌myf-5的表达

背景：MG-132是蛋白酶体抑制剂的一种，有报道显示其对失神经骨骼肌萎缩有延缓作用。 目的：进一步验证蛋白酶体抑制剂MG-132对大鼠骨骼肌成肌调节因子myf-5基因表达的影响。 方法：SD大鼠随机被分成3组，空白对照组不切断坐骨神经，仅做假手术，去神经组和去神经MG-132干预组切断坐骨神经1 cm以上，制作失神经骨骼肌动物模型，去神经MG-132干预组肌肉内注射MG-132。分别于去神经第2，7，28 d处死大鼠。用反转录聚合酶链式反应技术检测myf-5 mRNA表达情况，Western-blot检测myf-5蛋白表达的变化。 结果及结论：在去神经支配后第2，7，28天，与空白对照组比较，去神经组、去神经MG-132干预组myf-5mRNA和蛋白质均表达上调(P < 0.01)；去神经MG-132干预组myf-5mRNA和蛋白表达较去神经组均明显上调(P < 0.01)。结果提示蛋白酶体抑制剂MG-132可以通过抑制泛素-蛋白酶体途径来上调myf-5的表达，从而起到延缓骨骼肌萎缩的作用。     

失神经骨骼肌萎缩中泛素蛋白连接酶Murf1和核转录因子NF-κB表达与被动运动干预

背景：蛋白质分解是延缓肌萎缩发生的关键环节,在慢性病性、制动性肌萎缩中泛素蛋白连接酶Murf1和核转录因子NF-κB的表达增加,被动运动已被证实可以有效抑制肌萎缩的发生。 目的：探讨泛素蛋白连接酶Murf1和核转录因子NF-κB在大鼠失神经肌萎缩中不同时段的表达,以及被动运动对失神经骨骼肌Murf1和NF-κB表达的影响。 方法：假手术组大鼠不切断右下肢坐骨神经,失神经组、失神经被动运动组大鼠切断右下肢坐骨神经。术后1 d起,将失神经被动运动组大鼠置于自制的网夹内,拉出右后肢,抓住趾部,与脊柱呈45°向后外方牵拉,至右后肢完全伸直,再将右后肢推向身体,使之完全屈曲紧贴身体,每天训练2次,每次屈伸运动300下,3 min/次,直至切取标本之日。干预2,14,28 d后,采用RT-PCR与Western Blot技术分别检测Murf1,NF-κB mRNA和蛋白质的表达。 结果与结论：与假手术组比较,各时间点失神经组Murf1,NF-κB mRNA及蛋白的表达均明显增加(P < 0.05);与失神经组比较,各时间点失神经被动运动组Murf1及NF-κB mRNA的表达均显著降低(P < 0.01)。失神经支配后肌湿质量比明显下降,被动运动14 d时肌湿质量比明显高于失神经组(P < 0.05)。失神经腓肠肌中Murf1,NF-κB mRNA和蛋白的表达与肌湿质量呈负相关(r= -0.795,P < 0.01;r=-0.834,P < 0.01),提示被动运动可能通过降低Murf1和NF-κB的表达发挥肌萎缩防治作用。     

大鼠肌源性干细胞移植对失神经腓肠肌萎缩进程的影响

背景：目前，国内外有关肌源性干细胞移植的研究主要集中在治疗肌营养不良性萎缩症方面，尚未见涉及将肌源性干细胞应用于失神经肌萎缩综合治疗的报道。 目的：探讨大鼠肌源性干细胞移植对失神经腓肠肌萎缩进程的影响。 设计、时间及地点：随机对照动物观察，于2007-02/2008-07在沈阳医学院完成。 材料：成年健康雄性Wister大鼠19只，由沈阳医学院实验动物中心提供。 方法：取3只大鼠，无菌条件下切取肱三头肌，体外分离培养肌源性干细胞，贴壁法纯化扩增。余16只大鼠均切断右后肢胫神经，建立失神经腓肠肌模型，分为2组：细胞移植组于已切断的胫神经支配的腓肠肌的内外侧注射经DAPI标记的肌源性干细胞悬液0.2 mL，模型对照组于相同位置注射等量生理盐水，培养4周。 主要观察指标：采用计算机生物信号采集处理系统测定反映肌张力的腓肠肌阈强度恢复率和最适强度恢复率变化，通过电子天平计算肌湿质量残存率，应用图像分析系统测定肌纤维横截面积残存率。 结果：与模型对照组比较，细胞移植组失神经腓肠肌的阈强度恢复率、最适强度恢复率均明显降低(P < 0.01，P < 0.05)，肌湿质量残存率、肌纤维横截面积残存率均明显升高(P < 0.01)。 结论：肌源性干细胞移植对大鼠失神经肌萎缩进程有较明显的延缓作用。     

失神经状态下胫骨骨折断端骨痂成骨的组织学变化

摘要 背景：有研究表明神经系统在骨折的修复重建中发挥重要的作用，但其具体机制尚未阐明，中枢神经及神经生长因子对骨痂中成骨的影响至今少有报道。 目的：观察失神经状态下胫骨骨折断端骨痂成骨的组织学变化。 方法：用SD大鼠建立左胫骨闭合骨折髓内固定大鼠模型，建模成功后随机为3组，左胫骨骨折组；T10脊髓横断组：于左胫骨骨折后，横断切除T10段脊髓约0.3 cm，制成T10脊髓完全性损伤大鼠胫骨骨折模型；神经生长因子治疗组：建立T10脊髓完全性损伤大鼠胫骨骨折模型后，肌注神经生长因子。术后各组均用苏木精伊红染色法观察骨组织形态变化，骨钙素免疫组织化学法观察骨痂中成骨情况，透射电镜观察成骨细胞内微结构变化。 结果与结论：T10脊髓横断组大鼠在失神经状态下，骨痂中成骨细胞的数量减少，骨钙素表达减少，成骨细胞内细胞器功能低下。神经生长因子治疗组的以上各组织学观察指标均较T10脊髓横断组均有不同程度的改善。结果显示，神经生长因子可部分改善脊髓横断失神经状态下的骨组织再生情况。     

Toward noninvasive monitoring of ongoing electrical activity of human uterus and fetal heart and brain

Objective

To evaluate whether a full-coverage fetal-maternal scanner can noninvasively monitor ongoing electrophysiological activity of maternal and fetal organs.

Differential Effects of Fondaparinux and Bemiparin on Angiogenic and Vasculogenesis-like processes

Introduction

Conventional therapy for venous thromboembolism or acute coronary syndrome involves the administration of glycoanticoagulants (heparins) or oligosaccharides (fondaparinux). We evaluated the effects of such drugs on angiogenesis and vasculogenesis-like models.

Materials and Methods

Human umbilical vein endothelial cells or human endothelial progenitor cells were treated with bemiparin, fondaparinux or unfractionated heparin, at concentrations reflecting the doses used in clinical practice. After 24 h, cell viability, proliferation, tubule formation and angiogenic molecular mechanisms, such as activation of the serine/threonine kinase AKT, were assessed. In vivo angiogenesis was studied using a Matrigel sponge assay in mice.

Results

Bemiparin gave a significant decrease of in vitro angiogenesis as shown by the reduction of endothelial cell tubule network, while both fondaparinux and unfractionated heparin did not show any significant effect. In assays of Matrigel sponge invasion in mice, unfractionated heparin was able to stimulate angiogenesis and, conversely, bemiparin inhibited angiogenesis. Furthermore, both bemiparin and fondaparinux caused a significant reduction in an in vitro vasculogenesis-like model, as demonstrated by the decrease of tubule network after co-seeding of endothelial progenitor cells and human umbilical vein endothelial cells. In addition, unfractionated heparin but not bemiparin was able to increase AKT phosphorylation.

Conclusions

In in vitro experiments, bemiparin was the only drug to show an anti-angiogenic and vasculogenic-like effect, unfractionated heparin showed only a trend to increase in angiogenesis assay and fondaparinux affected only the vasculogenesis-like model. Notably, the in vivo experiments corroborated these data. Such results are important for the choice of a patient-tailored therapy.     

Health consequences of acute and chronic marihuana use

Chemical content, assay procedures, and pharmacokinetics of cannabis sativa are discussed briefly. Cannabinoid cellular effects relating to chromosomes and immunity including cellular metabolism and allergic reactions are presented. Gross and microscopic brain pathology due to cannabis use is reviewed involving EEG alterations, psychopathology including aggressive behaviour as well as properties of psychomotor impairment, tolerance and dependence. Cardiopulmonary effects of marihuana are recorded under pulmonary pharmacological effects including the macrophage defense system and effects of smoke constituents; under cardiovascular effects cardiac toxicity and possible mechanism of action are discussed. Alterations of reproductive hormonal production and maturation of reproductive cells by marihuana in males and females with attendant impairment of reproductive function or fertility including reproductive outcome are reported. Field studies with healthy chronic cannabis users in Jamaica, Greece and Costa Rica are related as to observed medical alterations. Potential clinical effects are summarized in point form.     

Rapid‐acting antidepressant ketamine,its metabolites and other candidates: A historical overview and future perspective

Major depressive disorder (MDD) is one of the most disabling psychiatric disorders. Approximately one‐third of the patients with MDD are treatment resistant to the current antidepressants. There is also a significant therapeutic time lag of weeks to months. Furthermore, depression in patients with bipolar disorder (BD) is typically poorly responsive to antidepressants. Therefore, there exists an unmet medical need for rapidly acting antidepressants with beneficial effects in treatment‐resistant patients with MDD or BD. Accumulating evidence suggests that the N‐methyl‐D‐aspartate receptor (NMDAR) antagonist ketamine produces rapid and sustained antidepressant effects in treatment‐resistant patients with MDD or BD. Ketamine is a racemic mixture comprising equal parts of (R)‐ketamine (or arketamine) and (S)‐ketamine (or esketamine). Because (S)‐ketamine has higher affinity for NMDAR than (R)‐ketamine, esketamine was developed as an antidepressant. On 5 March 2019, esketamine nasal spray was approved by the US Food and Drug Administration. However, preclinical data suggest that (R)‐ketamine exerts greater potency and longer‐lasting antidepressant effects than (S)‐ketamine in animal models of depression and that (R)‐ketamine has less detrimental side‐effects than (R,S)‐ketamine or (S)‐ketamine. In this article, the author reviews the historical overview of the antidepressant actions of enantiomers of ketamine and its major metabolites norketamine and hydroxynorketamine. Furthermore, the author discusses the other potential rapid‐acting antidepressant candidates (i.e., NMDAR antagonists and modulators, low‐voltage‐sensitive T‐type calcium channel inhibitor, potassium channel Kir4.1 inhibitor, negative modulators of γ‐aminobutyric acid, and type A [GABA_A] receptors) to compare them with ketamine. Moreover, the molecular and cellular mechanisms of ketamine’s antidepressant effects are discussed.     

产后抑郁与分娩前后孕酮、雌二醇变化的相关性研究

目的探讨分娩前后一周的血清雌二醇(E2)、孕酮(P)对产后抑郁的影响。方法选取2012年3月-2012年9月在贵阳医学院附属医院就诊的395例孕产妇为研究对象,采用爱丁堡产后抑郁量表(EPDS)对其产后抑郁情况进行评定,并用采用生物素双抗体夹心酶联免疫吸附法(ELISA)测定产妇血清雌二醇(E2)、孕酮(P)、五羟色胺(5-HT)水平。结果 1产后一周抑郁症状检出人数为48例,检出率为12.15%。2抑郁组与非抑郁组产后血清雌孕激素水平差异有统计学意义(P0.05)。3相关分析显示:产后EPDS得分与产前血清雌二醇水平、产前产后血清孕酮水平及产后孕酮、雌二醇下降幅度呈正相关、与产后5-HT、雌二醇水平呈负相关(r=-0.881~0.920,P0.01)。结论分娩后产妇的血清雌孕激素水平下降,产妇雌孕激素下降过快可能是导致产后抑郁发病的生物学因素之一。     

Thrombosis and acute coronary syndrome

Acute coronary syndromes (ACS) represent the main clinical manifestation of atherosclerotic progression in the coronary district. Thrombosis plays a critical role in the patho-anatomical of ACS, as disruption of an atherosclerotic plaque exposes flowing blood to subendothelial collagen, tissue factor, and other procoagulant molecules that trigger activation of platelets and formation of fibrin within the vessel lumen.Endothelial damage/dysfunction, inflammation and coagulation are closely related to the pathophysiology of ACS and may be inter-related.Platelets play key roles in both the formation of the atheromatous plaque and clinical presentation of acute atherothrombotic events following plaque rupture. In the pathogenesis of the ACS, blood clotting activation has a crucial role and thrombin generation and TF may represent useful markers for the identification of patients at high risk of vascular events. Lipoprotein-associated phospholipase A2 (Lp-PLA2) represents the crossroads between lipid metabolism and inflammatory response.     

Zinc, copper and magnesium concentration in serum and CSF of patients with neurological disorders

Zinc (Zn), copper (Cu) and magnesium (Mg) concentrations in cerebrospinal fluid (CSF) and serum were determined with atomic absorption spectrophotometry in 74 patients suffering from various neurological diseases, and in 28 healthy controls. Increased CSF zinc levels were found in the group of peripheral nervous system diseases (P less than 0.01) and in the cases of different neurological syndromes with increased CSF protein concentration (P less than 0.001). Increased CSF and serum copper levels were found in the cases with increased CSF protein levels (P less than 0.05). It is probable that the damaged blood-brain-barrier (BBB) permits the passage of the trace elements Zn, Cu and of Mg into the subarachnoid space. Decreased serum Cu levels (P less than 0.01) were found in the group of multiple sclerosis (MS). The findings are correlated to those of previous communications.     

Dual-task clinical and functional MRI correlates in Parkinson's disease with postural instability and gait disorders

BackgroundDual-task is a challenge for Parkinson's disease patients with postural instability and gait disorders (PD-PIGD).ObjectiveThis study investigated clinical, cognitive and functional brain correlates of dual-task deficits in PD-PIGD patients using quantitative gait analysis, neuropsychological evaluations and functional MRI (fMRI).MethodsTwenty-three PD-PIGD patients performed a clinical assessment of gait/balance abilities. Single and dual-task Timed-Up-and-Go tests were monitored using an optoelectronic system to study turning velocity. Patients underwent executive-attentive function evaluation and two fMRI tasks: motor-task (foot anti-phase movements), and dual-task (foot anti-phase movements while counting backwards by threes starting from 100). Twenty-three healthy subjects underwent neuropsychological and fMRI assessments.ResultsDual-task in PD-PIGD patients resulted in worse gait performance, particularly during turning. Performing the dual-task relative to the motor-fMRI task, healthy subjects showed widespread increased recruitment of sensorimotor, cognitive and cerebellar areas and reduced activity of inferior frontal and supramarginal gyri, while PD-PIGD patients showed increased recruitment of inferior frontal gyrus and supplementary motor area and reduced activity of primary motor, supramarginal and caudate areas. Dual-task gait alterations in patients correlated with balance and executive deficits and with altered dual-task fMRI brain activity of frontal areas.ConclusionsThis study suggested the correlation between dual-task gait difficulties, postural instability and executive dysfunction in PD-PIGD patients. FMRI results suggest that an optimized recruitment of motor and cognitive networks is associated with a better dual-task performance in PD-PIGD. Future studies should evaluate the effect of specific gait/balance and dual-task trainings to improve gait parameters and optimize brain functional activity during dual-tasks.