Co-transplantation of Neural Stem Cells and Schwann Cells within Poly (lactide-co-glycolide acid) Scaffolds Facilitates Axonal Regeneration in Hemisected Rat Spinal Cord

背景 为了促进脊髓损伤后的轴突再生,已经开发了各种组织工程学方法。我们的目的是研究是否神经干细胞能在PLGA支架中存活,与雪旺细胞共移植时被诱导向神经元分化,并形成突触联系,最终促进轴突及髓鞘化和运动功能。 方法 神经干细胞和雪旺细胞种植于PLGA取向支架,然后移植于半横断大鼠脊髓。 对照组大鼠也半横断后,但移植的支架中仅有神经干细胞或无细胞。分析神经干细胞存活、迁移、分化及突触形成情况,轴突再生及髓鞘化情况和运动功能。 结果 有神经干细胞存活下来,但是大部分迁移到邻近脊髓而死亡。与雪旺细胞共移植,神经干细胞存活情况改善,并且可被诱导向神经元分化,还肯能形成突触连接。当种植细胞后,轴突再生和髓鞘化情况及运动功能改善了。实验组的运动诱发电位恢复率及波幅显著高于对照组。同侧二次半横断后运动诱发电位再次消失,运动功能消失数天后恢复。但是对侧二次半横断后双侧运动功能完全消失。 结论 神经干细胞可在PLGA支架内存活。在体内,雪旺细胞可促进神经干细胞存活,并且向神经元分化,后者甚至可能形成了突触连接。种植了细胞的支架促进了轴突再生和髓鞘化及运动功能恢复。但是再生轴突对运动功能的恢复有限。     

Functional recovery following traumatic spinal cord injury mediated by a unique polymer scaffold seeded with neural stem cells and Schwann cells

Background The most important objective of transplant studies in the injured spinal cord has been to provide a favorable environment for axonal growth. Moreover, the continuing discovery of new grafts is providing new potentially interesting transplant candidates. Our purpose was to observe the morphological and functional repair effects of the co-transplantation of neural stem cell （NSC）, Schwann ceils （SCs） and poly lactide-co-glycolide acid （PLGA） on the spinal cord injury of rats.Methods A scaffold of PLGA was fabricated. NSCs and SCs were cultured, with the NSCs labeled with 5-bromodeoxyuridine, and the complex of NSC/PLGA or NSC＋SCs/PLGA were constructed. Thirty-six Wistar rats were randomly divided into three groups： group A （transplantation of PLGA）, group B （transplantation of NSC/PLGA） and group C （transplantation of NSC＋SCs/PLGA）. The 3 mm length of the right hemicord was removed under the microscope in all rats. The PLGA or the complex of PLGA-celIs were implanted into the injury site. Basso-Beattie-Bresnahan （BBB）locomotion scores, motor and somatosensory evoked potential of lower limbs were examined to learn the rehabilitation of sensory and motor function at 4 weeks, 8 weeks, 12 weeks and 24 weeks after injury. All the recovered spinal cord injury （SCI） tissues were observed with HE staining, immunohistochemistry, and transelectronmicroscopy to identify the survival, migration and differentiation of the transplanted cells and the regeneration of neural fibres at 4 weeks, 8 weeks,12 weeks and 24 weeks after injury.Results （1） From 4 weeks to 24 weeks after injury, the BBB locomotion scores of cell-transplanted groups were better than those of the non-cell-transplanted group, especially group C （P 〈0.05）. The amplitudes of the somatosensory evoked potential （SEP） and motor-evoked potential （MEP） were improved after injury in groups B and C, but the amplitude of SEP and MEP at 4 weeks was lower than that at 12 weeks and 24 weeks after injury. Compared with group B, the amplitude of SEP and MEP in group C was improved. The amplitude of SEP and MEP was not improved after injury in group A. （2） HE staining revealed the volume of the scaffold decreased and the number of cells in the scaffold increased. Newly-grown capillaries also could be seen. Immunohistochemistry staining showed the transplanted NSCs could survive and migrate until 24 weeks and they could differentiate into neurons and oligodendrocytes. The regenerated axons were observed in the scaffold-cell complex with transelectronmicroscopy. The above manifestations were more extensive in group C.Conclusions The transplanted NSC can survive and migrate in the spinal cord of rats up to 24 weeks after injury, and they can differentiate into various neural cells. Co-transplantation of cells/PLGA can promote the functional recovery of the injured spinal cord. The effect of co-transplanting NSC＋SCs/PLGA is better than transplanting NSC/PLGA alone.     

神经干细胞移植联合腹腔注射促红细胞生成素对横断性脊髓损伤大鼠神经轴突的修复作用

目的: 探讨神经干细胞(NSCs)与促红细胞生成素(EPO)共同作用于横断性脊髓损伤大鼠后对损伤区轴突的修复作用,为临床治疗脊髓损伤提供理论依据。方法: 40只雌性成年Wistar大鼠,建立T10全横断大鼠脊髓损伤模型后,随机分为对照组、NSCs组、EPO组和联合治疗组,每组10只。术后8周采用BDA皮质脊髓束顺行追踪法和荧光金(FG)皮质脊髓束逆行追踪法评估损伤区脊髓神经轴突再生情况,同时分期采用实验性脊髓损伤运动功能BBB评分法评价大鼠后肢功能恢复情况。结果: BDA 免疫荧光染色和FG免疫荧光染色,联合治疗组可见大量被BDA-cy3红色荧光标记的再生轴突,其中部分再生轴突穿越损伤区到达远端;NSCs组仅见少量轴突再生,无神经轴突通过脊髓损伤区;EPO组偶见散在的神经纤维再生;对照组无明显的轴突再生。联合治疗组大脑皮质中可见少量被FG标记的椎体细胞及轴突发出金黄色荧光,其余3组大脑皮质中无FG标记细胞。大鼠后肢功能BBB评分,在术后1周及1周以后各时段,联合治疗组大鼠BBB评分均高于其他各组(P<0.05)。结论: 脊髓损伤后移植NSCs联合腹腔注射EPO可有效促进脊髓损伤区神经轴突的再生以及脊髓损伤大鼠后肢运动功能的恢复。     

Functional electrical stimulation increases neural stem/progenitor cell proliferation and neurogenesis in the subventricular zone of rats with stroke

Background Functional electrical stimulation (FES) is known to promote the recovery of motor function in rats with ischemia and to upregulate the expression of growth factors which support brain neurog...     

神经干细胞移植对脑挫伤大鼠神经功能恢复神经元存活和轴突再生的影响

目的 观察神经干细胞(NSCs)移植对脑挫伤大鼠神经功能恢复影响,并探讨其机制.方法 24只SD大鼠以投币法分为3组:假手术组、手术组和NSCs移植组.采用自由落体致大鼠皮质运动区脑损伤模型,将培养纯化并鉴定的NSCs于术后当天移植入损伤位点周围;术后0d、3d、7d、14d行神经功能缺失(NSS)评分,观察动物运动和平衡功能缺损与恢复情况;14d时取脑组织用免疫荧光技术检测hochest标记的移植NSCs在体内存活、迁移;用神经元核蛋白(NeuN)、生长相关蛋白(GAP-43)抗体检测并计数宿主神经元存活和局部轴突再生.结果 与假手术组比较,脑外伤组大鼠脑挫伤后即出现不同程度抽搐,瘫痪,平衡功能缺失.神经功能缺损评分较假手术组明显升高,并随时间推移有所降低.而NSC移植组的NSS评分至第7天后与单纯手术组比较有明显减少[(4.38±0.74)分,(5.50±1.07)分,P＜0.01].Ho-chest标记的移植NSCs能在宿主脑组织存活,并向四周迁移.免疫组化染色显示宿主NeuN阳性神经元[(51.46±3.303)个,(42.83±5.401)个,P＜0.01]和GAP-43阳性纤维数量[(13.3±1.7)个,(8.7±1.1)个,P＜0.01]在NSC移植组明显增多.结论 NSCs移植能在挫伤脑组织存活、迁移,并促进宿主神经元存活、局部轴突再生和改善脑挫伤大鼠神经功能.     

Induction of functional recovery by co-transplantation of neural stem cells and Schwann cells in a rat spinal cord contusion injury model

Objective To study the transplantation efficacy of neural stem cells （NSCs） and Schwann cells （SC） in a rat model of spinal cord contusion injury. Methods Multipotent neural stem cells （NSCs） and Schwann cells were harvested from the spinal cords of embryonic rats at 16 days post coitus and sciatic nerves of newborn rats, respectively. The differential characteristics of NSCs in vitro induced by either serum-based culture or co-culture with SC were analyzed by immunofluorescence. NSCs and SCs were co-transplanted into adult rats having undergone spinal cord contusion at T9 level. The animals were weekly monitored using the Basso-Beattie-Bresnahan locomotor rating system to evaluate functional recovery from contusion-induced spinal cord injury. Migration and differentiation of transplanted NSCs were studied in tissue sections using immunohistochemical staining. Results Embryonic spinal cord-derived NSCs differentiated into a large number of oligodendrocytes in serum-based culture upon the withdrawal of mitogens. In cocultures with SCs, NSCs differentiated into neuron more readily. Rats with spinal cord contusion injury which had undergone transplantation of NSCs and SCs into the intraspinal cavity demonstrated a moderate improvement in motor functions. Conclusions SC may contribute to neuronal differentiation of NSCs in vitro and in vivo. Transplantation of NSCs and SCs into the affected area may be a feasible approach to promoting motor recovery in patients after spinal cord injury.     

外科植入引导牙周组织再生载药PLGA/CS/nHA复合膜的制备及表征

目的 制备聚乳酸-羟基乙酸共聚物(PLGA)/壳聚糖(CS)/纳米羟基磷灰石(nHA)多孔性载药膜,用于外科植入牙周引导组织再生,并评价其体外性能.方法 按照PLGA/CS的质量比将实验设为4组:分别为100/0、90/10、80/20、70/30,采用冷冻干燥法制备PLGA/CS/nHA复合膜,并用聚乙烯吡咯烷酮(PVP)作为致孔剂.依据孔隙率、吸水率、力学性能、体外降解率筛选出最优质量比的PLGA/CS/nHA复合膜作为药物载体,制备克林霉素缓释膜.采用扫描电子显微镜观察PLGA/CS/nHA复合膜的表面形貌,无水乙醇液体置换法检测复合膜的孔隙率,质量干湿率比考察复合膜的吸水率,电子万能材料实验机测试复合膜的湿态力学性能,质量损失考察膜的降解率,紫外分光光度法考察载药膜的体外药物释放特性.体外实验:在载药膜上接种牙周膜成纤维细胞(PLFs),培养1～7 d,采用CCK-8法测定细胞活性和增殖情况.结果 PLGA/CS质量比为90∶10时制备的PLGA/CS/nHA复合膜最为理想,孔隙率为(28.66±1.35)％,吸水率为(108.65±2.27)％,拉伸强度为(2.36±0.04) MPa,断裂伸长率为(203.64±3.89)％,断裂力为(45.98±2.46)N,30 d时降解率为(17.60±0.86)％,最大每日释放量为150 μg/mL,平稳释放药物并维持有效药物浓度时间＞15 d,载药膜能促进牙周膜成纤维细胞的增殖.结论 本研究制备的载药PLGA/CS/nHA复合膜孔隙率适中,体外降解与组织生长相适应,力学测试结果能够创造和维持牙周引导组织生长特定的空间,在一定时间内能持续稳定释放药物.     

Synergistic effect of schwann cells and retinoic acid on differentiation and synaptogenesis of hippocampal neural stem cells in vitro

INTRODUCTION Schwann cells (SCs) secrete growth factors or NGF-like proteins, such as nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), NT-3, basic fibroblast growth factor (bFGF), and glial cell line-derived neurotrophic factor (GDNF)[…     

Effect of oxymatrine on specific cytotoxic T lymphocyte surface programmed death receptor-1 expression in patients with chronic hepatitis B

Background  Oxymatrine has certain antiviral effects in the treatment of chronic hepatitis B (CHB), but its exact mechanism is unclear. The objective of the present study was to explore oxymatrine’s antiviral mechanism by studying its effect on the hepatitis B virus (HBV) specific cytotoxic T lymphocyte (CTL) surface programmed death receptor-1 (PD-1) expression in CHB patients.

Methods  Sixty-five CHB patients who had HBV DNA³10⁴ copies/ml, positive HBeAg, positive human leukocyte antigen (HLA)-A2, alanine aminotransferase (ALT) >2´upper limit of normal value (ULN) were randomly divided into two groups: treatment group (n=33), treated with an intravenous infusion of 600 mg oxymatrine in glucose solution once a day for a month, then with a 200 mg oxymatrine oral capsule three times a day, and a 200 mg silibin meglumine tablet three times a day; control group (n=32) patients were treated only with silibin meglumine tablet, method and dosage were the same as those of treatment group. Three months later, peripheral blood HBV-specific CTL surface PD-1 expression, HBV-specific CTL level, HBV DNA, HBeAg, and results of liver function tests were analyzed and compared.

Results  Three months post-treatment, in the treatment group, peripheral blood HBV-specific CTL surface PD-1 expression ((19.42±15.94)%) decreased significantly compared to the pretreatment level ((31.30±24.06)%; P <0.05), and decreased significantly compared to that of control group three months after treatment ((29.45±21.62)%; P <0.05). HBV-specific CTL level ((0.42±0.07)%) significantly increased compared with the pretreatment ((0.29±0.15)%; P <0.01), and the control group posttreatment level was (0.31±0.15)% (P <0.05). HBV DNA level in 11 cases became negative (HBV DNA<500 copies/ml, 33.33%), which was higher than that of the control group after treatment (two cases, 6.25%; χ²=7.45, P <0.01), HBeAg of nine cases turned negative (27.27%), which was higher than that of the control group after treatment (one case, 3.13%; χ²=7.27, P <0.01).

Conclusion  Oxymatrine could downregulate peripheral blood HBV-specific CTL surface PD-1 expression in CHB patients, increase HBV-specific CTL level, which may be one of the possible mechanisms by which oxymatrine clears or inhibits HBV in CHB patients.

     

负载NY-ESO-1多肽的树突状细胞激发特异性细胞毒性T淋巴细胞反应

目的:探讨以NY-ESO-1为靶抗原、树突状细胞(dendritic cell,DCs)为抗原载体激发特异性细胞毒性T淋巴细胞(cytotoxic T lymphocytes,CTLs)反应的能力,以明确特异性CTLs的抗肿瘤免疫功能.方法:在临床前实验基础上选择2014年11月至2015年10月于中国医学科学院肿瘤医院治疗的符合入选标准的15例Ⅱ～Ⅲ期HLA-A0201+NY-ESO-1+胃癌患者外周血,分离单个核细胞(peripheral blood mononuclear cells,PBMCs)和外周血淋巴细胞(peripheral blood lymphocytes,PBLs),并诱导出成熟DCs (mature dendritic cell,mDCs);将人工合成的NY-ESO-1多肽负载mDCs后通过流式细胞仪(flow cytometry,FCM)分析细胞表型,检测体外反复致敏PBLs后负载NY-ESO-1的DCs激发特异性CTLs的能力以及CTLs对NY-ESO-1+胃癌细胞的体外杀伤活性,同时患者回输CTLs细胞,每2周1次,共回输2次,检测回输前后患者外周血细胞因子和特异性CTLs水平变化.结果:采用FCM分析DCs细胞表型显示HLA-DR+ CD11c+细胞为93.6％±1.2％,其中CD80+细胞为87.3％±3.6％,CD83+细胞为82.8％±2.5％,CD86+细胞为93.4％±6.4％.患者外周血分离的PBLs经NY-ESO-1多肽负载的DCs反复诱导后,细胞不断增殖,其中未负载多肽的DCs也能促进PBLs增殖,但细胞增殖指数(proliferation index,PI)明显低于负载多肽的DCs,两者比较差异有统计学意义(P＜0.05).负载NY-ESO-1多肽DCs诱导的NY-ESO-1多肽特异性的CTLs比例较未负载NY-ESO-1多肽DCs诱导的对照组明显升高(5.2％±1.2％vs0.4％±0.1％,P＜0.05),且致敏后CTLs对NY-ESO-1+胃癌细胞及负载NY-ESO-1+多肽T2靶细胞的杀伤率明显高于对照组.输注CTLs细胞后,患者体内血清中细胞因子IFN-γ、IL-2、IL-12水平较治疗前显著升高[(132.9±10.2)μg/Lvs.(46.4±3.1)μg/L;(101.3±6.4) μg/Lvs.(26.7±1.2) μg/L;(51.3±2.6) μg/Lvs.(26.4±1.1) μg/L;P均＜0.05],且患者外周血特异性CTLs细胞比例明显升高.结论:负载NY-ESO-1多肽的DCs体内外均具有激发特异性CTLs反应的能力,可诱导明显的抗肿瘤免疫效应.     

不同条件对胎鼠海马神经干细胞增殖分化的影响

目的:探讨不同条件对胎鼠海马神经干细胞的增殖与分化的影响.方法:从胎鼠海马获取神经干细胞;新生鼠坐骨神经获取雪旺细胞.培养成功后对细胞进行鉴定.将提取的神经干细胞放在不同的培养条件下:雪旺细胞与神经干细胞共培养、DMEM/F12 bFGF EGF及DMEM/F12进行比较,观察其增殖和分化的情况.结果:含雪旺细胞的共培养组神经干细胞生长分化得最好,bFGF EGF组次之,DMEM/F12组生长的最差;共培养组细胞团之间建立了良好的突触联系,尤其是远距离的细胞间更为明显.此现象在bFGF EGF组及DMEM/F12组则没有出现,且该两组生长速度也较共培养组差.结论:雪旺细胞能更好的促进神经干细胞的生长、增殖和分化,它为神经干细胞提供了与活体内相似的环境 .     

IL-17A抑制Th2细胞分化减轻哮喘小鼠气道嗜酸性粒细胞炎症

目的 研究IL-17A对哮喘小鼠Th2细胞分化及其相关炎症的作用.方法 24只C57BL/6J小鼠按随机数字表法分为对照组、哮喘组和IL-17A处理组(n=8).哮喘组和IL-17A处理组予以卵清蛋白(ovalbumin,OVA)致敏及激发.每次雾化激发前1h,IL-17A处理组给予重组小鼠IL-17A气道滴入.各步对照均予以生理盐水.末次激发后24h处死小鼠,收集支气管肺泡灌洗液(bronchoalveolar lavage fluid,BALF)行细胞总数及分类计数.ELISA检测BALF中IL-4、IL-5、IFN-γ、IL-17A的浓度.HE和PAS染色及半定量评分评估小鼠肺部病理变化.流式细胞术检测脾脏和支气管淋巴结Th细胞分化.免疫磁珠分选健康小鼠幼稚CD4+T细胞,用Th2极化培养基体外培养,并给予IL-17A或等量PBS干预,检测Th2细胞的增殖、凋亡和分化.结果 哮喘组较对照组,BALF中细胞总数、嗜酸性粒细胞数及其比例(P＜0.05)、IL-4、IL-5、IL-17A浓度均显著增高(P＜0.05),IFN-γ浓度显著下降(P＜0.05);支气管、血管周围炎症细胞浸润和杯状细胞化生明显加重(P＜0.01);脾脏和淋巴结Th2细胞分化比例显著增高(P＜0.05).IL-17A处理组较哮喘组,BALF中的细胞总数[(26.00±5.43)×104/mLvs(58.40 ±26.93)×104/mL,P＜0.05]、嗜酸性粒细胞数[(8.04±1.98)×104/mL vs(31.95±12.28)×104/mL,P＜0.05]及其比例[(29.93 ±3.03)％ vs(53.47 ±6.62)％,P＜0.01]显著降低,而中性粒细胞数及其比例无明显变化;BALF中Th2相关因子IL-4浓度[(9.86 ±2.77) pg/mL vs(28.13 ±4.62) pg/mL,P＜0.01]、IL-5浓度[(7.30 ±0.50) pg/mL vs(10.50±1.10) pg/mL,P＜0.01]均显著降低;支气管、血管周围炎症细胞浸润减轻,HE染色半定量评分降低[(2.00 ±0.51)vs(3.12 ±0.64),P＜0.05],杯状细胞化生减少[(0.80 ±0.45)vs(2.40 ±0.55),P＜0.01];脾脏[(2.24±0.44)％vs(4.82±1.83)％,P＜0.01]和淋巴结[(7.05±0.58)％vs(10.57±1.35)％,P＜0.05]中Th2细胞分化比例显著减少.极化培养的幼稚CD4+T细胞,予IL-17A干预后,诱导分化的Th2细胞比例显著减少(P＜0.05),而增殖和凋亡无显著变化.结论 IL-17A有抑制Th2细胞分化,减轻哮喘小鼠气道嗜酸性粒细胞炎症的作用.     

丝氨酸羟甲基转移酶2在小鼠肝再生过程中的变化规律及作用

目的 探索丝氨酸羟甲基转移酶2(serine hydroxymethyl transferase 2,SHMT2)在小鼠肝再生过程中的表达规律,以及其对小鼠肝再生是否有促进作用.方法 SPF级C57BL/6小鼠120只分为肝切除组(2/3 PH)、假手术组(SHAM)、腺病毒干扰组(siSHMT2)及注射生理盐水对照组(Control),每组30只;肝切除组下设1、3、5、7、9d5个时相点,每个时相点6只.小鼠肝切除之后分别取1、3、5、7、9d的肝脏组织及血清,采用qPCR、Western blot和免疫组化检测SHMT2及其下游分子甘氨酸脱氢酶(glycine dehydrogenase,GLDC)的变化规律、血清中丙氨酸转氨酶(alanine transaminase,ALT)和谷草转氨酶(aspartate transaminase,AST)的浓度.取注射腺病毒干扰SHMT2第5天的肝脏组织,通过Westernblot和观察荧光强度,确定转染效果,并检测血浆中ALT和AST水平,免疫组化检测增殖细胞核抗原(proliferating cell nuclear antigen,PCNA).结果 SHMT2及其下游分子GLDC在小鼠肝再生的后第5、7天表达最高,qPCR检测结果显示,SHMT2第5天的表达量是第1天的1.63倍(P＜0.05).在干扰SHMT2之后,小鼠第5天再生肝脏的质量由(0.79±0.13)g降低至(0.63 ±0.ll)g(P ＜0.05),再生度由(36.37±2.21)％降低至(31.33±1.92)％,肝指数由(3.76±0.44)％降低至(3.13±0.29)％,并且肝功能指标ALT由(70.00±9.52) U/L升高至(154.15±16.49) U/L,AST由(140.09±32.85) U/L升高至(403.41±68.63) U/L(P＜0.05),PCNA阳性率从(53.6±2.3)％降低至(39.0±3.2)％(P＜0.05).结论 SHMT2在肝脏再生的后期高表达,促进残肝的再生,其机制可能与增强肝脏对缺血、缺氧的耐受,提高三磷酸腺苷水平有关.     

Clinical characteristics and prognosis of heart failure with normal left ventricular ejection fraction in elderly patients

heart failure with normal ejection fraction. Based on the previous studies, HFNEF has a significant morbidity and mortality and is associated with a similar prognosis to heart failure with reduced ejection fraction (HFREF). The present study aimed to investigate the clinical characteristics and prognosis of HFNEF in elderly patients.

Methods  Consecutive elderly patients (≥60 years old) hospitalized for the first episode of heart failure (HF) in Beijing Hospital from January 2003 to December 2009 were retrospectively recruited. Three hundred and ten patients with HF were eligible for our study. As recently recommended, a cut-off value of 50% was used to distinguish HFNEF (LVEF≥50%) from HFREF (LVEF<50%). Data were retrospectively obtained from hospital records and databases. Follow-up data were obtained by telephone and from hospital records. For every eligible patient, the clinical characteristics and prognosis were collected and compared between the HFNEF and HFREF groups.

Results  Patients with HFNEF accounted for 54.5% of all cases of elderly patients with HF. Compared with HFREF, the elderly patients with HFNEF had a higher proportion of females (62.1% vs. 32.6%, P <0.001), higher body mass index (BMI) ((24.9±4.7) vs. (23.5±4.0) kg/m², P=0.011), higher systolic blood pressure at admission ((141.5±22.6) vs. (134.3±18.6) mmHg, P=0.002), but lower hemoglobin levels ((118.3±22.7) vs. (125.8±23.8) g/L, P=0.005). The incidence of coronary heart disease (43.2% vs. 65.2%, P <0.001) and myocardial infarction (16.6% vs. 46.1%, P <0.001) were significantly lower in elderly patients with HFNEF than in those with HFREF (P <0.001). With a mean follow-up of 33.5 (0.5–93) months, 120 patients (38.7%) died, including 94 (30.3%) cardiac deaths. The HFNEF group had fewer deaths than the HFREF group at the end of the first follow-up (46/169 (27.2%) vs. 58/141 (41.1%)) and at the end of the second follow-up (56/169 (33.1%) vs. 64/141 (45.4%)). Kaplan-Meier survival analysis showed a significantly higher survival rate in elderly patients with HFNEF than those with HFREF (P=0.021 for total mortality and P <0.001 for cardiac mortality). Multiple Logistic regression analysis showed that LVEF <50% was an independent risk factor for death in elderly patients with HF.

Conclusions  More than half of elderly patients with HF have a normal LVEF. The prognosis of the elderly patients with HFNEF is poor, though slightly better than the elderly patients with HFREF.

     

类风湿关节炎患者髓系来源的抑制细胞促进自身B细胞增殖

目的:探讨类风湿关节炎(rheumatoid arthritis,RA)患者髓系来源的抑制细胞(myeloid-derived suppressor cells,MDSC)对自身B细胞增殖的影响,揭示MDSC在RA发病中的作用.方法:健康对照15例,RA患者38例,按28-关节疾病活动度分值(28-joint disease activity score,DAS28)分为高疾病活动度组(DAS28 ＞5.1)、中疾病活动度组(3.2＜ DAS28≤5.1)和低疾病活动度组(2.6＜ DAS28≤3.2),流式细胞术检测其外周血MDSC细胞的比例;同时分选10例高疾病活动度RA患者外周血B细胞和MDSC细胞体外共培养,羟基荧光素二醋酸盐琥珀酰亚胺酯(carboxyfluorescein diacetate succinimidyl ester,CFSE)法检测B细胞的增殖.结果:高疾病活动度RA外周血MDSC比例(7.13％±2.17％)相对于健康成年人(4.79％±1.02％)、中活动度患者(5.35％±1.36％)和低活动度患者(4.72％±1.08％)明显增加(P＜0.05),而中、低疾病活动度RA之间及其二者与健康成年人之间差异皆无统计学意义(P＞0.05);MDSC比例与患者DAS28分值成正相关(P＜0.05),与年龄、病程、类风湿因子(rheumatoid factor,RF)、抗环瓜氨酸多肽(cyclic citrullinated peptide,CCP)抗体等无相关性;MDSC共培养不抑制反而促进B细胞的增殖(P＜0.01).结论:MDSC在高疾病活动度RA患者外周血中明显增加,与疾病活动度呈正相关,并可在体外促进自身B细胞的增殖,提示MDSC可能通过调节B细胞的功能参与RA的疾病进程.     

Splenectomy protects experimental rats from cerebral damage after stroke due to anti-inflammatory effects

Background A recent study demonstrated that the inflammatory response accompanying necrotic brain injury played an important role in stroke.Thus,inhibition of this response may help to stop the expansi...     

神经干细胞移植联合促红细胞生成素对大鼠脊髓损伤的修复作用

目的:观察神经干细胞(NSCs)联合促红细胞生成素(EPO)对横断性大鼠脊髓损伤的修复作用,为临床治疗脊髓损伤提供理论依据。方法:40只成年雌性Wistar大鼠建立大鼠T10全横断脊髓损伤模型,并随机分为对照组、NSCs组、EPO组和NSCs+EPO组,每组10只。术后8周采用NF-200免疫组织化学染色和免疫荧光染色对各组大鼠损伤区脊髓神经纤维再生情况进行形态学观察;应用BBB评分评估各组大鼠后肢运动功能恢复情况。结果:组织形态学观察,对照组大鼠横断处脊髓组织残端萎缩,脊髓白质和灰质间可见大量空洞形成,未见有明显的神经纤维再生;NSCs+EPO组大鼠横断处脊髓组织残端轻度萎缩,横断区可见大量呈杂乱、无序生长的神经纤维,可见有连续性神经纤维通过脊髓横断区,脊髓白质和灰质间可见少量空洞形成。NSCs+EPO组大鼠中,FITC共轭抗神经丝蛋白抗体NF-200标记的再生神经纤维在横断区头侧大量再生,呈无序状生长,并通过损伤区到达尾侧;NSCs组大鼠可见少量神经纤维再生,未通过损伤区到达尾侧。NSCs+EPO组大鼠后肢运动功能BBB评分,术后7 d内均高于其他各组(P<0.05);NSCs组大鼠后肢运动功能BBB评分术后7 d内均高于对照组和EPO组(P<0.05)。结论:NSCs移植联合腹腔注射EPO可有效促进大鼠损伤脊髓功能的恢复、轴突的存活和再生。     

Cx43修饰人脐血源基质细胞输注阻抑白血病MRD小鼠造血干细胞移植后复发

目的 观察间隙连接蛋白43(connexin 43,Cx43)修饰人脐血源基质细胞(human umbilical cord blood-derived stromal cells,hUCBDSCs)体外对L615小鼠白血病细胞株凋亡以及在体对白血病微小残留病(minimal residual disease,MRD)小鼠疾病进展的影响.方法 通过Cx43过表达腺病毒(Ad-Cx43-GFP)上调hUCBDSCs中Cx43表达,体外构建L615+Cx43+hUCBDSCs共培养模型,检测其对L615细胞凋亡的影响.建立L615细胞低瘤负荷的MRD小鼠模型,分为骨髓(bone marrow,BM)移植组和Cx43+hUCBDSCs+ BM移植组进行移植,以正常L615小鼠作为对照,检测移植后外周血象、骨髓涂片、组织病理及骨髓Cx43表达变化等.结果 Ad-Cx43-GFP能够在mRNA和蛋白水平显著上调hUCBDSCs中Cx43表达.L615+Cx43+hUCBDSCs移植组L615细胞凋亡比例较对照组显著升高[(8.93±1.24)％ vs(3.53±0.13)％,P＜0.01].对MRD小鼠移植后,Cx43+hUCBDSCs+BM移植组外周血WBC和PLT恢复更快,17d时接近正常水平,而BM移植组外周血WBC和PLT恢复延迟,17 d时低于正常水平;17 d时,Cx43+hUCBDSCs+BM移植组骨髓涂片原始细胞比例较BM移植组显著降低[(7.67±1.25)％ vs (56.33±1.25)％,P＜0.01];与BM移植组比较,Cx43+hUCBDSCs+BM移植组肝、脾、骨髓的白血病浸润程度较低,同时骨髓中Cx43蛋白表达增加.结论 上调hUCBDSCs中Cx43表达能在体外促进L615细胞凋亡,Cx43+hUCBDSCs+BM联合移植能够促进MRD小鼠外周血WBC和PLT恢复,阻抑MRD小鼠移植后复发.     

Impaired brachial artery flow-mediated dilation and increased carotid intima-media thickness in rheumatoid arthritis patients

Background  Carotid artery intima-media thickness (CIMT) and brachial artery flow-mediated dilation percentage (FMD%) are common parameters used for detecting subclinical atherosclerosis. This study compared subclinical atherosclerosis of the carotid and brachial arteries in rheumatoid arthritis (RA) patients and healthy controls using high resolution ultrasonography. We also investigated their correlation with clinical factors and the association between FMD% and CIMT.

Methods  One hundred and two RA patients and 46 age-gender matched healthy controls were included in the study. FMD of the brachial artery and CIMT were measured ultrasonographically. Patients with diabetes mellitus, hypertension, renal failure, history of cardiovascular or cerebrovascular disease were excluded. Subjects who were receiving or used high dose steroids were also excluded.

Results  The CIMT was significantly higher in patients than that in the control group ((0.697±0.053) vs. (0.554±0.051) mm, P <0.001), whereas brachial artery FMD% was lower in patients than that in the controls ((5.454±2.653)% vs. (8.477±2.851)%, P <0.001). CIMT was related to age, disease duration, tender and swollen joint score, C-reactive protein, systolic blood pressure and high-density lipoprotein. However, FMD% was only association with systolic blood pressure. There was no significant correlation between CIMT and FMD%.

Conclusions  Compared with the healthy control subjects, RA patients without clinically evident cardiovascular disease had subclinical atherosclerosis in terms of impaired FMD% and increased CIMT. FMD% and CIMT may measure a different stage of subclinical atherosclerosis in RA patients.

     

右美托咪定对谷氨酸所致PC12细胞损伤的保护作用及其机制

目的 研究右美托咪定(Dex)对谷氨酸所致PC12细胞损伤的保护作用及机制.方法 应用高浓度谷氨酸处理PC12细胞以建立细胞缺氧损伤模型.应用MTT法测定细胞存活率,采用试剂盒分别测定细胞培养液中乳酸脱氢酶释放量,细胞丙二醛含量和超氧化物歧化酶活力,DCFH-DA染色流式细胞仪检测细胞内活性氧水平,Fluo-8染色流式细胞仪检测细胞内钙离子含量,JC-1染色流式细胞仪检测细胞线粒体膜电位.结果 在0.01～100 μmol/L浓度范围内,Dex浓度依赖性地拮抗谷氨酸所致PC12细胞损伤,至100 μmol/L时,细胞存活率达到正常组的(86.6±2.2)％,显著高于模型组(P＜0.01),乳酸脱氢酶释放量为正常组的1.4±0.1倍,显著低于模型组(P＜0.01).1μmol/L Dex预处理谷氨酸损伤的PC12细胞,与模型组相比,能够显著降低丙二醛含量(P＜0.01),提高超氧化物歧化酶活力(P＜0.01),抑制胞内活性氧过度生成(P＜0.01),降低细胞内Ca2+浓度(P＜0.01),稳定细胞线粒体膜电位(P＜0.01).结论 Dex对谷氨酸所致PC12细胞损伤具有保护作用,其机制可能与Dex抗氧化和抑制细胞内钙超载,保护线粒体功能相关.