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31.
Dendrites and spines undergo dynamic changes in physiological and pathological conditions. Dendritic outgrowth has been observed in surviving neurons months after ischemia, which is associated with the functional compensation. It remains unclear how dendrites in surviving neurons are altered shortly after ischemia, which might reveal the mechanisms underlying neuronal survival. Using primary cortical cultures, we monitored the dendritic changes in individual neurons after oxygen-glucose deprivation (OGD). Two to four hours of OGD induced approximately 30–50% cell death in 24 h. However, the total dendritic length in surviving neurons was significantly increased after OGD with a peak at 6 h after re-oxygenation. The increase of dendritic length after OGD was mainly due to the sprouting rather than the extension of the dendrites. The dendritic outgrowth after 2 h of OGD was greater than that after 4 h of OGD. Application of NMDA receptor blocker MK-801 abolished OGD-induced dendritic outgrowth, whereas application of AMPA receptor antagonist CNQX had no significant effects. These results demonstrate a NMDA receptor-dependent dendritic plasticity shortly after OGD, which provides insights into the early response of surviving neurons after ischemia. 相似文献
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为了研究β-1,4-半乳糖基转移酶 和 (β-1,4-Gal T- and )蛋白表达的亚细胞结构定位 ,本实验构建了β-1,4-Gal T- 和 融合绿色荧光蛋白 (GFP)表达质粒 ,分别将构建的质粒转染到 PC12细胞和肝癌 772 1细胞中 ,在荧光显微镜下观察β-1,4-Gal T- 和 在其中表达的亚细胞结构定位。发现 ,β-1,4-Gal T- 和 主要表达在这两种细胞的细胞核旁的 Golgi复合体 ,说明它们主要分布在 Golgi复合体上。提示它们可能是在 Golgi复合体参与蛋白质的糖链修饰 相似文献
33.
Yoshitake Baba Shun Inagaki Sae Nakagawa Makoto Kobayashi Toshiyuki Kaneko Takanobu Takihara 《Nutrients》2021,13(5)
Matcha, a type of green tea, has a higher amino acid content than other types of tea. We previously examined the ability of matcha to improve cognitive function in older adults and determined that continuous matcha intake improves attention and executive function. This study aimed to compare the effects of matcha and caffeine and clarify the differences between these effects. The study was registered at the University Hospital Medical Information Network (UMIN000036578). The effect of single and continuous intake was compared, and the usefulness of continuous intake was evaluated under the stress condition. The Uchida–Kraepelin test (UKT) was used to induce mild acute stress, and the Cognitrax was used to evaluate cognitive function. A single dose of caffeine improved attentional function during or after stress loading. The reduced reaction time in the Cognitrax, observed following a single dose of matcha, was likely due to caffeine. The matcha group showed an increase in the amount of work after continuous intake, whereas the caffeine group only showed an increase in the amount of work for the UKT after a single dose. Ingesting matcha with caffeine improves both attention and work performance when suffering from psychological stress compared with caffeine alone. 相似文献
34.
Lately, matcha green tea has gained popularity as a beverage and food additive. It has proved to be effective in preventing obesity and related metabolic syndromes. However, the underlying mechanisms of its control effects against non-alcoholic fatty liver disease (NAFLD) are complicated and remain elusive. In the present study, we performed an in vivo experiment using male C57BL/6 mice fed with a high-fat diet and simultaneously treated with matcha for six weeks. Serum biochemical parameters, histological changes, lipid accumulation, inflammatory cytokines, and relevant indicators were examined. Dietary supplementation of matcha effectively prevented excessive accumulation of visceral and hepatic lipid, elevated blood glucose, dyslipidemia, abnormal liver function, and steatosis hepatitis. RNA sequencing analyses of differentially expressed genes in liver samples indicated that matcha treatment decreased the activity of lipid droplet-associated proteins and increased the activity of cytochrome P450 enzymes, suggesting improved metabolic capacity and liver function. The current study provided evidence for new dietary strategies based on matcha supplementation to ameliorate lipotoxicity-induced obesity and NALFD. 相似文献
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目的对比纳米碳与吲哚菁绿(ICG)在腹腔镜胃癌根治术淋巴结清扫方面的优劣性。方法回顾性分析2016年1月至2019年12月接受腹腔镜胃癌根治术的167例患者资料,根据所使用的示踪剂种类,分为纳米碳组130例、ICG组37例,应用GraphPad Prism 8.0统计软件进行分析,围术期指标及淋巴结清扫数目等计量资料以(±s)表示,采用独立t检验;术后并发症、二次手术率等计数指标比较采用χ2检验,P<0.05为差异有统计学意义。结果两种示踪剂对不同病理分期胃癌的淋巴结清扫效果差异无统计学意义。在各种胃癌根治术式中,淋巴结分拣均有助于提高淋巴结总检出数。纳米碳组较ICG组更有助于提高根治性全胃切除术第5站淋巴结的清扫数目(P=0.02)、根治性近端胃切除术第1站淋巴结的清扫数目(P=0.03)以及根治性远端胃淋巴结的总清扫数目(P=0.03)。在提高淋巴结检出率方面,两种示踪剂差异无统计学意义。结论纳米碳与吲哚菁绿在不同病理分期中的总体淋巴结清扫效果差异无统计学意义。无论使用何种示踪剂,均提倡淋巴结分拣。纳米碳较吲哚菁绿更有助于提高根治性全胃第5站淋巴结的清扫数、根治性近端胃第1站淋巴结的清扫数以及根治性远端胃淋巴结的总清扫数目。 相似文献
38.
Hong-Wei Han Ning Shi Yi-Ping Zou Yuan-Peng Zhang Ye Lin Zi Yin Zhi-Xiang Jian Hao-Sheng Jin 《World journal of gastrointestinal surgery》2021,13(3):323-329
BACKGROUNDLiver cancer is a malignant tumor with a high incidence. At present, the most effective treatment is laparoscopic hepatectomy (LH). Indocyanine green fluorescence imaging (ICG-FI) has become an important tool in LH, and the most common fluorescent types of tumors are total fluorescence, partial fluorescence, and rim fluorescence.CASE SUMMARYWe presented four cases of LH guided by ICG-FI in which we also observed the fourth special fluorescent type. When the tumor or intrahepatic stone compresses the adjacent bile duct to cause local cholestasis, the liver segment or subsegment with obstructed bile drainage will show strong fluorescence. Complete removal of the lesion together with the fluorescent liver parenchyma may help reduce the risk of tumor or stone recurrence.CONCLUSIONThis type of partial fluorescence can indicate local biliary compression, and the resection method is related to bile drainage, which may be called functional anatomical hepatectomy and ensures radical resection of the lesion. 相似文献
39.
Weijie Zhu Shengwei Xiong Yucai Wu Dengxiang Zhang Chen Huang Han Hao Lei Zhang Kunlin Yang Peng Zhang Hongjian Zhu Xuesong Li Liqun Zhou 《Translational andrology and urology》2021,10(3):1071
BackgroundTo describe our technique for using an intraureteral injection of indocyanine green (ICG) and visualization under near-infrared fluorescence (NIRF) to facilitate challenging upper urinary tract reconstructions (UUTRs) and to present the comparative outcomes.MethodsWe collected 36 patients who underwent laparoscopic UUTRs between April 2019 and March 2020, and we divided the patients into two groups based on the use of ICG (ICG group and non-ICG group). Demographic characteristics, perioperative outcomes, and functional outcomes were compared between the two groups.ResultsThere were 18 cases in the ICG group and 18 cases in the non-ICG group, respectively. There were no differences in the baseline characteristics between the two groups. The intraoperative time to identification of the ureter (TIU; 20.9±11.7 vs. 30.0±14.6 min, P=0.03) and length of postoperative hospital stay (LPHS; 11.1±3.0 vs. 16.6±10.0 days, P=0.03) were significantly shorter in the ICG group. There was also a trend for lesser time for locating the stricture (43.0±27.9 vs. 55.4±18.6 min, P=0.14) and lower estimated blood loss (EBL) in the ICG group patients (88.3±75.4 vs. 91.7±46.2 mL, P=0.22). During the mean 3.8-month follow-up for the ICG group and the 6.2-month for the non-ICG group, there was a trend for more severe complications in the non-ICG group.ConclusionsVisualizing intraureteral ICG under NIRF is useful in challenging UUTRs, allows for rapid ureteral identification and accurate real-time delineation of the ureteral stricture margins, and provides encouraging follow-up outcomes compared with those in the non-ICG group. 相似文献
40.
Materials are distributed throughout the body of mammals by fractal networks of branching tubes. Based on the scaling laws of the fractal structure, the vascular tree is reduced to an equivalent one-dimensional, tube model. A dispersion–convection partial differential equation with constant coefficients describes the heterogeneous concentration profile of an intravascular tracer in the vascular tree. A simple model for the mammalian circulatory system is built in entirely physiological terms consisting of a ring shaped, one-dimensional tube which corresponds to the arterial, venular, and pulmonary trees, successively. The model incorporates the blood flow heterogeneity of the mammalian circulatory system. Model predictions are fitted to published concentration-time data of indocyanine green injected in humans and dogs. Close agreement was found with parameter values within the expected physiological range. © 2003 Biomedical Engineering Society.
PAC2003: 8710+e, 8719Hh, 8719Uv 相似文献