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1.
目的通过对急性心肌梗死后心力衰竭(HFMI)大鼠模型给药治疗,评估加味温胆汤对大鼠心肌能量代谢水平和心肌超微结构的影响。方法SD雄性大鼠随机分为两组,每组15只,造模组通过手术结扎冠状动脉左前降支造模,假手术组完成穿刺但并未结扎左前降支,术后饲养72 h,对两组大鼠进行慢性心衰评分并加以比较。将造模组15只大鼠分为3组,每组5只,中药组经口喂加味温胆汤,曲美他嗪组给予曲美他嗪溶液,对照组喂养生理盐水,给药4周后空腹抽取3组鼠尾静脉血,检测并比较各组大鼠心肌能量代谢因子:血清肌钙蛋白(cTnI)、心肌过氧化物酶体增殖物激活受体γ辅激活因子1α(PGC-1α)水平;进行超声检查,测定并比较左室射血分数(LVEF);采集心肌样本进行HE染色(核染)和Masson染色(纤染),对心肌超微结构完整性进行评分。结果治疗4周后,中药组、曲美他嗪组大鼠LVEF数值均较治疗前显著增加(P<0.05),对照组与治疗前相比降低(P<0.05),但治疗后中药组大鼠LVEF数值高于曲美他嗪组(P<0.05);与治疗前相比,3组大鼠血清cTnI、PGC-1α表达水平差异有统计学意义(P<0.05),中药组<曲美他嗪组<对照组;治疗4周后,3组大鼠心肌超微结构完整性评分比较差异也具有统计学意义(P<0.05),中药组<曲美他嗪组<对照组。结论加味温胆汤对急性心肌梗死后心力衰竭大鼠的心肌能量代谢具有促进作用,对心肌超微结构的完整性具有保护作用,并能有效改善大鼠的心功能。  相似文献   
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Microglia, as the resident immune cells in the central nervous system, play important roles in regulating neuronal processes, such as neural excitability, synaptic activity, and apoptotic cell clearance. Growth factors can activate multiple signaling pathways in central nervous system microglia and can regulate their immune effects, but whether growth factors can affect the morphological characteristics and ultrastructure of microglia has not been reported. After microinjecting 300 nL of a growth factor cocktail, including 10 μg/mL epidermal growth factor, 10 μg/mL basic fibroblast growth factor, 10 μg/mL hepatocyte growth factor and 10 μg/mL insulin-like growth factor into adult rat cortex, we found that the number of IBA1-positive microglia around the injection area increased significantly, indicating local activation of microglia. All CD68-positive labeling co-localized with IBA1 in microglia. Cell bodies and protrusions of CD68-positive cells were strongly attached to or were engulfing neurons. Characteristic huge phagosomes were observed in activated phagocytes by electron microscopy. The phagosomes generally included non-degraded neuronal protrusions and mitochondria, yet they contained no myelin membrane or remnants, which might indicate selective phagocytosis by the phagocytes. The remnant myelin sheath after phagocytosis still had regenerative ability and formed "myelin-like" structures around phagocytes. These results show that microinjection of a growth factor cocktail into the cerebral cortex of rodents can locally activate microglia and induce selective phagocytosis of neural structures by phagocytes. The study was approved by the Institute of Laboratory Animal Science, Beijing Institute of Basic Medical Sciences(approval No. IACUC-AMMS-2014-501) on June 30, 2014.  相似文献   
4.
目的:以心肌线粒体为切入,观察“标本配穴”电针对慢性心肌缺血模型大鼠心肌线粒体结构、GAPDH、CS、CCO的酶活性及心肌组织ATP含量的影响,探讨“标本配穴”电针对慢性心肌缺血模型大鼠心肌线粒体的保护机制。方法:将30只Wistar雄性大鼠随机分为空白组、模型组、标本配穴组,每组10只。模型组、标本配穴组大鼠皮下注射盐酸异丙肾上腺素制备慢性心肌缺血大鼠模型。标本配穴组在造模结束后取“内关”“足三里”“关元”电针干预10 min,疏密波,2~100 Hz,1 mA,连续21天。运用透射电镜观察心肌线粒体结构变化,采用试剂盒检测3-磷酸甘油醛脱氢酶(GAPDH)、柠檬酸合成酶(CS)、细胞色素C氧化酶(CCO)的酶活性及心肌组织ATP含量。结果:与空白组比较,模型组线粒体结构破坏明显,大部分线粒体出现变形空泡化;而与模型组比较,标本配穴组线粒体结构损伤程度明显减轻。与空白组相比,模型组、标本配穴组心肌组织ATP含量、GAPDH、CS、CCO活性均明显降低(P<0.01)。但与模型组相比,标本配穴组4指标均显著增高(P<0.01),且心肌组织ATP含量与GAPDH、CS、CCO活性成线性相关。结论:在慢性心肌缺血状态下,标本配穴电针可提升线粒体呼吸酶活性,增加有氧呼吸产能效率,改善心脏能量代谢,从而减轻心肌细胞的结构破坏,对心肌组织起到保护作用。  相似文献   
5.
《Neuromodulation》2022,25(7):980-988
ObjectivesTo investigate the analgesic effect of high-voltage pulsed radiofrequency (HV-PRF) on the dorsal root ganglion (DRG) for neuropathic pain induced by spared nerve injury (SNI) in rats, especially the influence of this treatment on the DRG ultrastructure and voltage-gated sodium channel 1.7 (Nav1.7) level in the DRG.Materials and MethodsOne hundred fifty adult male Sprague-Dawley rats were randomly divided into five groups: Sham, SNI, Free-PRF, standard-voltage PRF (SV-PRF), and HV-PRF. The 45V-PRF and 85V-PRF procedures applied to the left L5 DRG were performed in SV-PRF group and the HV-PRF group, respectively, on day 7 after SNI, whereas no PRF was concurrently delivered in Free-PRF group. The paw mechanical withdrawal threshold (PMWT) was detected before SNI (baseline) and on days 1, 3, 7, 8, 10, 14, and 21. The changes of left L5 DRG ultrastructure were analyzed with transmission electron microscopy on days 14 and 21. The expression levels of Nav1.7 in left L5 DRG were detected by immunofluorescence and Western blot.ResultsCompared with the Free-PRF group, PMWT in the SV-PRF group and HV-PRF group were both significantly increased after PRF (all p < 0.05). Meanwhile, the PMWT was significantly higher in the HV-PRF group than that in the SV-PRF group on days 14 and 21 (all p < 0.05). There were statistically significant differences between the SV-PRF and Free-PRF groups (p < 0.05). Similarly, statistically significant difference was found between the HV-PRF and Free-PRF groups (p < 0.05). Especially, comparison of the SV-PRF group and the HV-PRF group revealed statistically significant difference (p < 0.05). The Nav1.7 levels were significantly downregulated in the SV-PRF group and HV-PRF groups compared to that in the Free-PRF group (all p < 0.01). A significantly lower Nav1.7 level was also found in the HV-PRF group compared to that in the SV-PRF group (p < 0.05).ConclusionsThe HV-PRF produces a better analgesic effect than SV-PRF applied to the DRG in SNI rats. The underlying mechanisms may be associated with improving the histopathological prognosis and the downregulation of Nav1.7 levels in the DRG.  相似文献   
6.
目的:探讨人脐带Wharton’s间充质干细胞(Wharton’s jelly-derived mesenchymal stem cells,WJMSCs)在输卵管炎性不孕症治疗中的应用前景。方法:成年雌性Wistar大鼠50只,随机分为输卵管炎症模型组(n=40)和对照组(n=10)。其中,模型组大鼠双侧输卵管注入混合菌后再随机分成5组,急性治疗前组(n=5),于造模后第20日取材;急性治疗组(n=10),于造模第20日,给予腹腔注射WJMSCs(1×106/ml),7 d/次,共3次,疗程结束1周后5只取材;慢性治疗前组(n=5),于造模后30 d取材;慢性治疗组(n=10),于造模第30日开始给予WJMSCs;方法同急性治疗组,疗程结束1周后5只取材;慢性模型组(n=10),造模后不给予任何处理,第51日5只取材,所有余下雌鼠分别与雄鼠同笼。检测比较急、慢性输卵管炎模型大鼠腹腔注射WJMSCs治疗前、后血清INF-γ和TNF-α水平、输卵管超微结构、单位面积输卵管腔上皮皱褶长度(Lu)和分泌颗粒的密度(D),以及各组受孕率及产仔数。结果:急性输卵管炎期,输卵管上皮被破坏,间质水肿,治疗后基本恢复正常。慢性输卵管炎期,上皮扁平化,黏膜下纤维化,治疗后无明显改善。急性输卵管炎治疗前组Lu值无明显变化,而D值显著下降,治疗后恢复正常;慢性输卵管炎治疗前组Lu、D值均明显降低,治疗后无明显好转。急、慢性输卵管炎治疗前组血清TNF-α和INF-γ水平均明显增高,治疗后急性组恢复到正常水平,而慢性治疗组虽有下降,但仍高于正常水平。急性输卵管炎治疗组受孕率、产仔数恢复正常。慢性输卵管炎治疗前、后,其受孕率、产仔数均明显下降。结论:WJMSCs腹腔注射治疗大鼠急性输卵管炎,能降低血清炎症因子,恢复输卵管结构和功能,恢复生育功能,但对慢性输卵管炎的治疗效果不明显,提示在急性期治疗输卵管炎有可能防止继发不孕的发生。  相似文献   
7.
Background: The use of various synthetic calcium phosphate compositions for the promotion of bone in bone defects is of potential interest because such materials may be tailor made and may bond to bone. There is yet an inadequate knowledge of the role of calcium phosphate composition and resorbability for the bone response. Purpose: The aim of the present study was to compare the ability of resorbable versus nonresorbable hydroxyapatite (HA) granules to promote new bone formation in cortical bone defects. Resorbable and nonresorbable HA granules, used as bone graft substitutes, were evaluated after 6 weeks and 3 months in the rabbit tibia. Circular defects (diameter 5.0 mm) were made in both tibias of 18 New Zealand white rabbits. The 36 defects were divided into three groups (six observations per group and time, respectively). The first group was augmented with resorbable HA granules, the second group was augmented with ceramic nonresorbable HA granules, and the third group was left without augmentation (control). The animals were killed after 6 weeks and 3 months, and the tissue was evaluated with light microscopic (LM) morphology and morphometry, scanning electron microscopy (SEM), and energy dispersive x‐ray analysis (EDX). Results: After 3 months LM morphometry revealed significantly more newly formed bone in the two HA augmented groups compared with that in the control. A close contact was found between both kinds of HA granules and new bone as viewed with light microscopy and SEM. A relatively slow degradation process was indicated by the small reduction of the total granule area in the cortical defects. However, LM observations showed a change of granule form. Pilot experiments using SEM‐EDX indicate that Ca and P contents had decreased in the resorbable HA granules between 6 weeks and 3 months. Further, a higher content of Ca and P was found in the newly formed bone close to granules, in comparison with more distant newly formed bone. Conclusions: Our results suggest that both resorbable and nonresorbable HA granules promote new bone formation in rabbit cortical defects, which does not occur in control defects.  相似文献   
8.
The continuous growth of the rat incisor is associated with renovation of the junctional epithelium and resorption of the periodontal ligament. The circumdental papilla separates the connective tissue suffering resorption from the rest of the gingiva. Laminin and collagen IV were detected by the immunoperoxidase technique on the basement membrane of all regions of the gingival epithelium of the rat incisor, except the internal basal lamina and the internal surface of the circumdental papilla. The internal basal lamina is formed by a granular electron-dense material, without the organization of a typical basal lamina. Areas of the internal surface of the circumdental papilla, negative for laminin and collagen IV, lack the basal lamina. These data suggest that these molecules are not components of the dento-epithelial junction of the distal surface of the rat incisor. In addition, the basal lamina is absent or fragmented on the internal surface of the circumdental papilla, adjacent to the areas of the connective tissue undergoing resorption.  相似文献   
9.
目的:从超微结构水平了解雪旺氏细胞标记物 S100蛋白在腺样囊性癌中的表达,进而分析腺样囊性癌中哪种细胞成份发生了雪旺氏细胞分化。方法:采用免疫电镜方法研究 S100蛋白,肌动蛋白(muscle actin,MA)在腺样囊性癌中的表达。结果:S100阳性细胞与 MA 阳性细胞具有相同的分布和超微结构。这种超微结构符合肌上皮细胞的超微结构特点。结论:腺样囊性癌中突变的肌上皮细胞可能发生了雪旺氏细胞分化。  相似文献   
10.
The basal lamina anionic sites of the epithelial attachment apparatus (EAA) were investigated at the electron microscopic level in adult rat periodontium. After 1M NaCl junctional epithelium detachment, an irregular and fluffy basal lamina-like structure appeared to cover the cementum surface. This structure reacted positively with polyethyleneimine (PEI), a strongly cationized ultrastruc-tural tracer, appearing to be composed of highly electron-dense microaggregates. Depending on section plane, double-tracked structures of undefined length were found within PEI precipitates and closely related to cementum collagen fibrils. After nitrous acid de-N-sulphation, 8 nm wide sets of two parallel lines were clearly identified. "Double tracks", i.e., sets of paired lines with peripherical PEI electron-dense material, were found to self-assemble to form dimers, clusters or more complex organizational patterns. From sensitivity towards nitrous acid oxidation and positive control observations, it was concluded that basal lamina anionic sites in the EAA. represented by PEI microaggregates, contain heparan sulfate proteoglycans (HSPGs). Furthermore, high resolution ultrastructural images demonstrated that HSPGs adopt a morphological appearance of "double tracks" in the tissue. On the other hand, the present findings suggest that HSPGs clusters, never found in the mucosal basement membrane used as positive control, may be related to a functional specificity of the tissue at the dento-gingival junction.  相似文献   
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