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991.
Han F Shioda N Moriguchi S Yamamoto Y Raie AY Yamaguchi Y Hino M Fukunaga K 《The Journal of pharmacology and experimental therapeutics》2008,326(1):127-134
Olfactory bulbectomy (OBX) in mice elicits impaired memory and cognitive functions. Here, we found that chronic oral administration of spiro[imidazo[1,2-a]pyridine-3,2-indan]-2(3H)-one (ZSET1446/ST101) (0.1-1 mg/kg/day), a novel cognitive enhancer, significantly improved memory deficits as assessed by Y-maze and novel object recognition tasks in OBX mice. Immunostaining of cholinergic neurons in the medial septum by using an anti-choline acetyltransferase antibody indicated that chronic ZSET1446 treatment did not rescue cholinergic neurons. However, chronic treatment significantly restored OBX-induced decreases both in calcium/calmodulin-dependent protein kinase II (CaMKII) and protein kinase C (PKC) phosphorylation without improving decreased extracellular signal-regulated kinase phosphorylation in the hippocampal CA1 region. Consistent with enhanced CaMKII and PKC phosphorylation, ZSET1446 treatment improved glutamate receptor 1 (Ser-831) phosphorylation in the hippocampal CA1 region. ZSET1446 treatment also significantly rescued impaired long-term potentiation (LTP) in the hippocampal CA1 region of OBX mice. Taken together, the cognition-enhancing effect of ZSET1446 is probably mediated in part by stimulation of CaMKII and PKC activities, which in turn rescue impaired hippocampal LTP in OBX mice. 相似文献
992.
背景:胶原膜是一种可吸收引导成骨材料,同种异体骨是较为理想的骨替代材料,但单独应用均有其不足,拟将两种材料结合使用以期达到理想效果.目的:利用膜引导组织再生技术,观察胶原膜复合同种骨颗粒修复兔桡骨节段性骨缺损的成骨速度和质量,并与单纯胶原膜进行比较.设计、时间及地点:同体对照观察实验,于2004-09/2005-02在中国辐射防护研究院医用组织库中心实验室完成.材料:胶原膜规格20 mm×20 mm,由北京天新福医疗器材有限公司提供.同种异体骨颗粒按美国组织库标准制备,直径0.2~0.7 mm,由山西省医用组织库提供.方法:健康成年新西兰大白兔40只,制备双侧15 mm桡骨缺损模型,采用同体对照方法,实验侧(左侧)缺损区移植胶原膜及同种骨粒,对照侧(右侧)仅移植胶原膜.主要观察指标:光镜组织学观察骨缺损愈合情况,计算机图像分析仪计算骨小梁的成骨面积,扫描电镜观察缺损再生修复情况.结果:①光镜组织学变化:实验侧新骨增生明显,迅速,以膜性化骨及软骨内化骨的方式由骨缺损周围向中央成骨或以同种骨粒为中心由周围向骨粒内成骨,最后骨膜形成,新髓腔不断扩大、再通,骨重建顺利,缺损修复完成.对照侧成骨方式以软骨化骨为主,新骨形成较同期实验侧慢,新骨成熟度不如实验组.②成骨面积图像分析:结果显示术后2,4,8周新生骨小梁成骨面积均大于同期对照侧(P<0.05).③扫描电镜观察:术后8周实验侧有较多分泌胶原的成骨细胞和带有较多突起的骨细胞,钙盐沉积,骨质排列开始有序.对照侧软骨与类骨质互相存在,低倍下骨基质排列无序,胶原纤维编织样排列.术后12周实验侧骨质排列有序,胶原粗大排列整齐,大量骨细胞方向有序,大量钙盐沉积,可见哈佛氏管和血管.对照侧骨质排列有序,但胶原纤维较细、基质钙化程度不如实验侧.结论:两种方法均能成骨修复缺损,但胶原膜复合同种异体骨粒组成骨速度快,且成骨质量优于单纯胶原膜组. 相似文献
993.
纳米羟基磷灰石粒子引起红细胞聚集的体外实验 总被引:2,自引:0,他引:2
背景:目前在纳米羟基磷灰石生物安全性实验中发现其引起红细胞聚集现象,是纳米羟基磷灰石血液相容性研究中亟待解决的问题。目的:探讨体外纳米羟基磷灰石引起红细胞聚集的机制。设计、时间及地点:体外细胞形态学观察实验,于2004-03/2006-06在武汉理工大学生物材料与工程研究中心实验室完成。材料:两种不同粒径羟基磷灰石粒子粉体由武汉理工大学生物医学材料与工程研究中心提供。方法:溶血实验评价材料对兔红细胞的影响,并对材料与红细胞共培养后做细胞形态学观察,Bialsche法检测纳米羟基磷灰石粒子与唾液酸的吸附量,绘制吸附等温线,纳米羟基磷灰石粒子与唾液酸共吸附作红外光谱分析。主要观察指标:纳米羟基磷灰石粒子对红细胞形态影响和超微结构观察,不同粒径的羟基磷灰石粒子对唾液酸的吸附量,纳米羟基磷灰石与唾液酸吸附后的红外光谱分析。结果:纳米羟基磷灰石粒子与兔红细胞共培养后可导致红细胞聚集,并且对细胞表面的唾液酸有强烈的吸附作用,红外光谱结果表明两者有明显的相互作用。结论:纳米粒子与红细胞体外共培养后,降低了细胞的Zeta电位和表面电荷密度,引起红细胞悬浮性下降,可能是导致聚集的发生的重要因素。 相似文献
994.
Jinghui Peng Shengbin Pei Yangyang Cui Yiqin Xia Yue Huang Xiaowei Wu Mingjie Zheng Miaomiao Weng Xu Han Hongtao Fu Lili Yang Wenbin Zhou Ziyi Fu Shui Wang Hui Xie 《Oncology Letters》2022,24(2)
In patients with triple-negative breast cancer (TNBC), high tumour mutation burden and aberrant oncogene expression profiles are some of the causes of poor prognosis. Therefore, it is necessary to identify aberrantly expressed oncogenes, since they have the potential to serve as therapeutic targets. Transient receptor potential channel 5 opposite strand (TRPC5OS) has been previously shown to function as a novel tumour inducer. However, the underlying mechanism of TRPC5OS function in TNBC remain to be elucidated. Therefore, in the present study TRPC5OS expression was first measured in tissue samples of patients with TNBC and a panel of breast cancer cell lines (ZR-75-1, MDA-MB-453, SK-BR-3, JIMT-1, BT474 and HCC1937) by using qRT-PCR and Western blotting. Subsequently, the possible effects of TRPC5OS on MDA-MB-231 cells proliferation were determined using Cell Counting Kit-8 and 5-Ethynyl-2′-deoxyuridine assays after Lentiviral transfection of MDA-MB-231. In addition, potential interaction partners of TRPC5OS were explored using liquid chromatography-mass spectrometry (LC-MS)/MS. Gene expression patterns following TRPC5OS overexpression were also detected in MDA-MB-231 cells by using High-throughput sequencing. Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) analysis were then used to systematically verify the potential interactions among the TRPC5OS-regulated genes. The potential relationship between TRPC5OS-interacting proteins and gene expression patterns were studied using Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) analysis. TRPC5OS expression was found to be significantly higher in TNBC tumour tissues and breast cancer cell lines compared with luminal tumour tissues and ZR-75-1. In addition, the overexpression of TRPC5OS significantly increased cell proliferation. High-throughput sequencing results revealed that 5,256 genes exhibited differential expression following TRPC5OS overexpression, including 3,269 upregulated genes and 1,987 downregulated genes. GO analysis results indicated that the functions of these differentially expressed genes were enriched in the categories of ‘cell division’ and ‘cell proliferation’ regulation. KEGG analysis showed that the TRPC5OS-regulated genes were associated with processes of ‘homologous recombination’ and ‘TNF signalling pathways’. Subsequently, 17 TRPC5OS-interacting proteins were found using LC-MS/MS and STRING analysis. The most important protein among interacting proteins was ENO1 which was associated with glycolysis and regulated proliferation of cancer. In summary, data from the present study suggest that TRPC5OS overexpression can increase TNBC cell proliferation and ENO1 may be a potential target protein mediated by TRPC5OS. Therefore, TRPC5OS may serve as a novel therapeutic target for TNBC. 相似文献
995.
Jingshu Ni Yong Liu Haiou Hong Xiangyong Kong Yongsheng Han Lei Zhang Yang Zhang Yuanzhi Zhang Changyi Hua Quanfu Wang Xia Wang Yao Huang Wang YiKun Dong Meili 《RSC advances》2022,12(29):18397
There is a great demand for the rapid and non-invasive atherosclerosis screening method. Cholesterol content in the epidermis of the skin is an early biomarker for atherosclerosis. Risk assessment of atherosclerosis can be achieved by measuring cholesterol in the epidermis. Here, we synthesised a new fluorescent digitonin derivative (FDD) for the non-invasive detection of skin cholesterol. The results of fluorescence spectroscopy studies indicated that the probe exhibited desirable selectivity for cholesterol. The proof-of-concept preclinical study confirmed that FDD can detect different concentrations of skin cholesterol; patients diagnosed with atherosclerotic cardiovascular disease and the at-risk atherosclerosis group exhibited higher skin cholesterol content than the normal group. The area under the ROC curve for distinguishing the normal/disease group was 0.9228 (95% confidence interval, 0.8938 to 0.9518), and the area under the ROC curve for distinguishing the normal/risk group was 0.9422 (95% confidence interval, 0.9178 to 0.9665). We anticipate that this non-invasive skin cholesterol test may be used as a risk assessment tool for atherosclerosis screening in a large population for further examination and intervention in high-risk populations.Digitonin was used to synthesise a fluorescence probe for the non-invasive detection of skin cholesterol. This non-invasive skin cholesterol method may be used as a risk assessment tool for atherosclerosis screening in a large population. 相似文献
996.
目的应用荧光定量RT-PCR检测乳腺癌外周血中的表达情况,并评价其表达的临床意义。方法用荧光定量RT-PCR方法检测49例乳腺癌患者外周血CK19mRNA表达。结果49例乳腺癌患者外周血中CK19mRNA检测阳性28例,阳性率57.1%,统计结果显示乳腺癌患者外周血CK19mRNA的表达阳性率在患者不同年龄、病理类别、临床分期、ER、PR状态的各组差异无显著性(P>0.05),在淋巴结转移状态间有显著差异。结论CK19mRNA可作为RT-PCR法检测乳腺癌患者外周血微转移的分子标志物,有助于早期预测乳腺癌发生血道微转移,指导临床治疗。 相似文献
997.
青年与老年结直肠癌临床病理与预后比较 总被引:7,自引:0,他引:7
为了探讨青年与老年结直肠癌的临床病理特征和预后的不同,回顾性分析1991年1月~2002年12月天津医科大学附属肿瘤医院手术治疗、经病理资料确诊且随访资料完整的青年结直肠癌(≤40岁)278例,老年结直肠癌(〉60岁)693例,应用SPSS10.0软件进行统计分析。结果示青年组结直肠癌与老年组结直肠癌相比出现症状时间较短,发病部位以直肠癌多见,病理类型较差,淋巴结转移常见,Duke分期较晚,但青年组与老年组之间总的生存期没有差别。初步研究结果提示,青年组与老年组结直肠癌患者临床病理特征有差异;但相同临床期别结直肠癌青年组预后并不比老年组差。 相似文献
998.
MGMT与hMLH1在胃癌组织中的表达及其临床相关性研究 总被引:1,自引:0,他引:1
目的:研究肿瘤修复基因蛋白产物MGMT、hMLH1在胃癌组织中的表达及其与胃癌临床病理特征的关系.方法:采用免疫组化方法(SP)检测96例胃癌切除标本中MGMT和hMLH1蛋白表达水平,并分析两者与胃癌临床病理特征的关系.结果:胃癌组织中MGMT和hMLH1在胃癌组织中的阳性率分别为74%(71/96)和65.6%(63/96).MGMT and hMLH1的表达在胃癌组织学分类、浸润深度、淋巴结转移、肿瘤分期以及术后有无复发或远处转移等临床指标中具有统计学意义,P<0.05;两者的表达在年龄、性别上的差异无统计学意义,P>0.05.Kendall's tau-b相关分析显示,MGMT与hMLH1在胃癌组织中的表达呈正相关,r=0.370,P<0.000 5.胃癌组织MGMT高表达或hMLH1高表达患者术后生存期要好于MGMT低表达或hMLH1低表达患者术后生存期,并且差异有统计学意义.结论:MGMT或hMLH1的表达与胃癌的发生密切相关,均具有抑制胃癌发生及发展的作用. 相似文献
999.
An efficient and catalyst-free methodology for the reductive cyclization of various disulfides using BH3NH3 as a reductant and CO2 as a C1 resource was developed. The desired 2-unsubstituted benzothiazole derivatives were obtained in good to excellent yields. Moreover, mechanism investigation demonstrated that BH3NH3 played an important role in the formation of benzothiazole. As a reducing agent, BH3NH3 reduced CO2 and cleaved the S–S bond of the disulfide efficiently. In addition, the N–H bond of the amino group was also activated by BH3NH3. To the best of our knowledge, this is an unprecedented catalyst-free protocol for the synthesis of 2-unsubstituted benzothiazole from bis(2-aminophenyl) disulfide and CO2.An efficient and catalyst-free methodology for the reductive cyclization of various disulfides using BH3NH3 as a reductant and CO2 as a C1 resource was developed. 相似文献
1000.