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目的 探讨我国弓形虫Chinese 1优势基因型感染对宿主脑组织铁代谢及脑损伤的影响。方法 将20只C57BL/6(体质量15~17 g)小鼠随机分为对照组和感染组,每组10只。感染组每只小鼠腹腔注射4 000个弓形虫Chinese 1优势基因型TgCtwh3虫株速殖子,对照组小鼠注射等量无菌PBS,饲养6 d后处死小鼠并取其脑组织。采用电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry, ICP⁃MS)检测小鼠脑组织铁元素水平;采用RNA芯片检测两组小鼠脑组织差异基因数目并对功能基因表达情况进行基因本体论(Gene Ontology, GO)功能富集;采用实时荧光定量PCR(fluorescent quantitative real⁃time PCR, qPCR)技术检测小鼠脑组织中弓形虫表面抗原1(Toxoplasma gondii surface antigen 1,TgSAG1)基因及部分锌铁调控蛋白(Zrt⁃ and Irt⁃like protein, ZIP)家族mRNA表达水平;采用光镜和电镜观察小鼠脑组织海马齿轮回(dentate gyrus, DG)超微结构;采用Western blotting检测谷胱甘肽过氧化物酶4(glutathione peroxidase 4, GPx4)蛋白表达水平;采用硫代巴比妥酸(TBA)法检测丙二醛(malondialdehyde, MDA)水平;采用免疫组化检测血管内皮生长因子(vascular endothelial growth factor, VEGF)蛋白表达光密度(optical density, OD)值。结果 光镜下可见感染组小鼠脑组织海马DG区细胞坏死,电镜下见感染组小鼠脑组织海马区出现胞质空泡化、核皱缩坏死、线粒体嵴断裂消融、自噬小体增加等超微结构变化。与对照组相比,感染组小鼠脑组织中铁元素水平上调[(32.92 ± 0.90) µg/g vs.(37.72 ± 1.10) µg/g;t = 3.397, P < 0.01];RNA芯片检测感染组小鼠脑组织发现721个基因上调、276个基因下调,差异表达基因在金属离子结合能力上有明显富集。与对照组相比,感染组小鼠脑组织金属元素转运体ZIP2 mRNA表达水平上调(t = 8.659,P < 0.05)、GPx4表达下降[(1.046 ± 0.025) vs. (0.720 ± 0.101);t = 3.129,P < 0.01])、MDA水平升高[(4.37 ± 0.33) nmol/mgprot vs.(5.93 ± 0.54) nmol/mgprot;t = 2.451,P < 0.05)]、VEGF蛋白平均OD值上调[(0.348 3 ± 0.017 8) vs. (0.490 6 ± 0.010 5);t = 6.641,P < 0.01]。结论 Chinese 1优势基因型弓形虫感染后,小鼠脑组织中铁元素蓄积、抗氧化能力下调、氧化应激水平升高,提示弓形虫感染可影响宿主脑组织铁代谢而导致脑损伤。 相似文献
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《Journal of vascular and interventional radiology : JVIR》2022,33(9):1034-1044.e29
PurposeTo assess the safety and tolerability of a vandetanib-eluting radiopaque embolic (BTG-002814) for transarterial chemoembolization (TACE) in patients with resectable liver malignancies.Materials and MethodsThe VEROnA clinical trial was a first-in-human, phase 0, single-arm, window-of-opportunity study. Eligible patients were aged ≥18 years and had resectable hepatocellular carcinoma (HCC) (Child-Pugh A) or metastatic colorectal cancer (mCRC). Patients received 1 mL of BTG-002814 transarterially (containing 100 mg of vandetanib) 7–21 days prior to surgery. The primary objectives were to establish the safety and tolerability of BTG-002814 and determine the concentrations of vandetanib and the N-desmethyl vandetanib metabolite in the plasma and resected liver after treatment. Biomarker studies included circulating proangiogenic factors, perfusion computed tomography, and dynamic contrast-enhanced magnetic resonance imaging.ResultsEight patients were enrolled: 2 with HCC and 6 with mCRC. There was 1 grade 3 adverse event (AE) before surgery and 18 after surgery; 6 AEs were deemed to be related to BTG-002814. Surgical resection was not delayed. Vandetanib was present in the plasma of all patients 12 days after treatment, with a mean maximum concentration of 24.3 ng/mL (standard deviation ± 13.94 ng/mL), and in resected liver tissue up to 32 days after treatment (441–404,000 ng/g). The median percentage of tumor necrosis was 92.5% (range, 5%–100%). There were no significant changes in perfusion imaging parameters after TACE.ConclusionsBTG-002814 has an acceptable safety profile in patients before surgery. The presence of vandetanib in the tumor specimens up to 32 days after treatment suggests sustained anticancer activity, while the low vandetanib levels in the plasma suggest minimal release into the systemic circulation. Further evaluation of this TACE combination is warranted in dose-finding and efficacy studies. 相似文献
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《Gait & posture》2022
BackgroundGait classification systems (GCS) may enable clinicians to differentiate gait patterns into clinically significant categories that assist in clinical decision-making and assessment of outcomes. Davids and Bagley in 2014 [1] described a GCS for children with cerebral palsy (GCS-CP). The purpose of our study was to use the GCS-CP for the first time on a sample of patients with CP and to evaluate the reliability and utility of the classification system.MethodsThe gait of 131 children with CP was retrospectively reviewed and classified according to Davids and Bagley’s classification using two-dimensional (2D) video and three-dimensional (3D) lower limb kinematics and kinetics. Gross Motor Function Classification System (GMFCS) levels were determined, and the Gait Profile Scores (GPS) calculated to characterize the sample concerning gait classification. The comparison between the groups was performed using the Kruskal-Wallis test with respect to the non-normal distribution of the data. The intrarater and interrater reliability was determined using the Kappa index (k) statistics with 95% CI.ResultsAll GCS-CP groups were represented within the evaluated sample. Of the 131 cases evaluated, 127 (96.95%) were able to be classified with respect to sagittal plane stance phase gait deviations. All patients in the sample were able to be classified with respect to sagittal plane swing phase and transverse plane gait deviations. The interrater reliability was 0.596 and 0.485 for the first and second levels of the classification, respectively, according to the Fleiss’s Kappa statistics. Intrarater reliability was 0.776 and 0.714 for the raters one and two, respectively, according to the Cohen’s Kappa statistics.SignificanceThe GCS-CP exhibited clinical utility, successfully classifying almost all subjects with CP in two planes, based upon kinematic and kinetic data. The classification is valid and has moderate interrater and moderate to substantial intrarater reliability. 相似文献
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Cadmium is a toxic metal that can damage the brain and other organs. This study aimed to explore the protective effects of Potentilla anserine L. polysaccharide (PAP) against CdCl2-induced neurotoxicity in N2a and SH-SY5Y cells and in the cerebral cortex of BALB/c mice. In addition, we aimed to identify the potential mechanisms underlying these protective effects. Relative to CdCl2 treatment alone, pretreatment with PAP prevented the reduction in cell viability evoked by CdCl2, decreased rates of apoptosis, promoted calcium homeostasis, decreased ROS accumulation, increased mitochondrial membrane potential, inhibited cytochrome C and AIF release, and prevented the cleavage of caspase-3 and PARP. In addition, PAP significantly decreased the CdCl2-induced phosphorylation of CaMKII, Akt, and mTOR. In conclusion, PAP represents a potential therapeutic agent for the treatment of Cd-induced neurotoxicity, functioning in part via attenuating the activation of the mitochondrial apoptosis pathway and the Ca2+-CaMKII-dependent Akt/mTOR pathway. 相似文献
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刘斌 《中国现代药物应用》2022,(3)
目的研究腹腔镜经脐单一部位幽门环肌切开术治疗小儿先天性肥厚性幽门狭窄的临床效果。方法100例小儿先天性肥厚性幽门狭窄患儿作为研究对象,按照随机方式分为观察组和对照组,每组50例。对照组采用腹腔镜幽门环肌切开术治疗,观察组采用腹腔镜经脐单一部位幽门环肌切开术治疗。观察记录患儿的手术结果及随访结果,并比较两组患儿手术时间、术后住院时间。结果手术过程顺利,100例患儿均成功完成手术,无一例中转开腹手术,无并发症发生。观察组患儿术后6 h将胃管取下,少量喂入温水后逐渐过渡到喂糖水、喂奶;对照组患儿术后24 h开始逐渐进食。患儿术后进行6个月的延续性随访,观察组患儿切口恢复美观,已经无法观察到切口瘢痕,两组患儿的生长发育均显示正常状态。观察组患儿手术时间(21.23±1.65)min及术后住院时间(5.58±1.98)d均显著短于对照组的(38.44±1.23)min、(9.67±1.22)d,差异具有统计学意义(P<0.05)。结论先天性肥厚性幽门狭窄患儿采用腹腔镜经脐单一部位幽门环肌切开术治疗,手术效果良好,手术创伤小而且安全。 相似文献
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目的 基于网络药理学研究香菇多糖抑制三阴乳腺癌(TNBC)的作用机制并采用细胞和动物实验进行验证。方法 通过GeneCards数据库和DisGeNET数据库筛选与TNBC相关基因靶点,利用TCMID、PubChem、SwissTargetPrediction和GeneCards数据库查询香菇多糖相关基因靶点。使用Sangerbox软件进行基因本体论(GO)富集和京都基因与基因组百科全书(KEGG)通路富集分析。结合STRING数据库与Cytoscape 3.7.0软件将共同靶点进行可视化处理,筛选核心靶点,构建"化合物-靶点-通路"网络。利用Metascape软件进行转录因子及相关调控基因特异富集。体外培养小鼠TNBC细胞4T1和人TNBC细胞MDA-MB-231,磺酰罗丹明B染色法观察香菇多糖(31.25、62.5、125、250、500、1 000μg·mL-1)对细胞存活率的影响;健康雌性BABLC小鼠sc接种1×106个4T1-Luc细胞构建TNBC模型,通过小动物活体成像系统观察香菇多糖(100、200 mg·kg-1)对肿瘤生长的影响,实时荧光定量PCR (qRT-PCR)技术检测肿瘤组织信号转导和转录活化因子3(STAT3)和血管内皮生长因子A (VEGFA) mRNA表达。结果 数据库及软件分析得到香菇多糖治疗TNBC关键靶点52个,靶点主要涉及PI3K-Akt、AGE-RAGE、HIF-1、MAPK信号通路和肿瘤蛋白多糖相关通路,PPI分析得到VEGFA、STAT3、MAPK1、IL2、TNF、RELA、AKT1、MAPK3、BCL2L1和HSP90AA1 10个hub基因。与对照组比较,香菇多糖对4T1和MDA-MB-231细胞存活率均有显著抑制作用(P<0.05、0.01),且作用呈浓度相关性;在给药14、21d后,与模型组比较,香菇多糖能够剂量相关性地抑制小鼠TNBC肿瘤的生长,高剂量组差异显著(P<0.05、0.01),21 d抑制率达到(91.9±4.7)%;与对照组比较,香菇多糖给药后能够剂量相关性抑制STAT3和VEGFA的mRNA表达,高剂量组差异显著(P<0.05、0.01)。结论 香菇多糖可通过多靶点、多途径协同作用抑制TNBC的生长。 相似文献