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1.
目的 对比研究朝鲜淫羊藿酸性多糖酯化还原前后的理化特性,并探讨其改善油酸诱导的肝癌HepG2细胞脂质堆积活性的差异。方法 采用高效凝胶渗透色谱法测定朝鲜淫羊藿酸性多糖(EFPA)的均一性和分子量,高效液相色谱法测定EFPA和酯化还原后朝鲜淫羊藿酸性多糖(EFPA-R)的单糖组成;采用油酸(OA)处理HepG2细胞诱导建立脂质蓄积模型,不同浓度EFPA与EFPA-R(10、30、100、300 μg·mL-1)分别和OA共同作用于细胞24 h,采用CCK-8试剂盒测定细胞存活率,油红O染色观察细胞内脂滴蓄积情况,并采用试剂盒测定细胞内总胆固醇(TC)、甘油三酯(TG)含量。结果 EFPA为成分均一的多糖组分,分子量为125.8 kDa,由甘露糖、葡萄糖、半乳糖、葡萄糖醛酸和阿拉伯糖组成,摩尔比为1.7∶7.4∶1.4∶1.8∶1.0,葡萄糖占比最大,EFPA-R由甘露糖、葡萄糖、半乳糖和阿拉伯糖组成,摩尔比为0.8∶10.6∶2.1∶1.0;在10-300 μg·mL-1范围内,EFPA和EFPA-R对HepG2细胞的抑制作用较弱,作为给药浓度;与空白组相比,模型组细胞中TC、TG含量显著升高(P < 0.01),细胞内红色脂滴显著增多,与模型组相比,EFPA可显著降低细胞中TC、TG含量(P < 0.01),明显减少细胞内红色脂滴(P < 0.05或P < 0.01),EFPA-R干预后细胞则无明显变化。结论 EFPA可明显改善HepG2细胞脂质堆积情况,且呈现剂量依赖性,而半乳糖醛酸(GalA)的存在可能是其抑制HepG2细胞脂质蓄积的关键因素。  相似文献   
2.
Neoadjuvant programmed cell death protein 1 (PD-1) blockade exhibits promising efficacy in patients with mismatch repair deficient (dMMR) colorectal cancer (CRC). However, discrepancies between radiological and histological findings have been reported in the PICC phase II trial (NCT 03926338). Therefore, we strived to discern radiological features associated with pathological complete response (pCR) based on computed tomography (CT) images. Data were obtained from the PICC trial that included 36 tumors from 34 locally advanced dMMR CRC patients, who received neoadjuvant PD-1 blockade for 3 months. Among the 36 tumors, 28 (77.8%) tumors achieved pCR. There were no statistically significant differences in tumor longitudinal diameter, the percentage change in tumor longitudinal diameter from baseline, primary tumor sidedness, clinical stage, extramural venous invasion status, intratumoral calcification, peritumoral fat infiltration, intestinal fistula and tumor necrosis between the pCR and non-pCR tumors. Otherwise, tumors with pCR had smaller posttreatment tumor maximum thickness (median: 10 mm vs 13 mm, P = .004) and higher percentage decrease in tumor maximum thickness from baseline (52.9% vs 21.6%, P = .005) compared to non-pCR tumors. Additionally, a higher proportion of the absence of vascular sign (P = .003, odds ratio [OR] = 25.870 [95% CI, 1.357-493.110]), nodular sign (P < .001, OR = 189.000 [95% CI, 10.464-3413.803]) and extramural enhancement sign (P = .003, OR = 21.667 [2.848-164.830]) was observed in tumors with pCR. In conclusion, these CT-defined radiological features may have the potential to serve as valuable tools for clinicians in identifying patients who have achieved pCR after neoadjuvant PD-1 blockade, particularly in individuals who are willing to adopt a watch-and-wait strategy.  相似文献   
3.
Krüppel-like factor 16 (KLF16), a member of the Krüppel-like factor (KLF) family, has been extensively investigated in multiple cancer types. However, the role of KLF16 in oral squamous cell carcinoma (OSCC) remains unknown. Thus, we conducted this study to investigate its related mechanism. KLF16 expression in OSCC cell lines was quantified by western blotting. Then, OECM1 and OC3 cells were divided into Blank, siCtrl, siKLF16#1 and siKLF16#2 groups. Subsequently, cell proliferation was detected using 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assays, cell migration and invasion were detected with wound healing and Transwell assays, and cell cycle distribution and cell apoptosis were detected via flow cytometry. KLF16, p21, CDK4, Cyclin D1 and p-Rb expression was detected by western blotting. Finally, xenograft models were established in nude mice to observe the in vivo effects of KLF16 on OSCC. KLF16 protein expression was upregulated in OSCC cells. Compared to the cells in the Blank group, the OECM1 and OC3 cells in the siKLF16#1 group and siKLF16#2 group exhibited a sharp decrease in proliferation but a remarkable increase in apoptosis. Moreover, the proportion of cells in the G0/G1 phase notably increased and that in the S phase decreased, with evident decreases in cell invasion and migration. Moreover, KLF16, cyclin-dependent kinase 4 (CDK4), Cyclin D1 and p-Rb protein expression was upregulated, but p21 expression was downregulated. The mice in the siKLF16#1 and siKLF16#2 xenograft model groups exhibited slower tumour growth and smaller tumours with evident downregulation of Ki67 expression compared to the mice in the Blank group. KLF16 expression was upregulated in OSCC cells, and interfering with KLF16 led to cell cycle arrest, inhibited OSCC cell growth and promoted cell apoptosis.  相似文献   
4.
Introduction: Collaborative interactions between several diverse biological processes govern the onset and progression of breast cancer. These processes include alterations in cellular metabolism, anti-tumor immune responses, DNA damage repair, proliferation, anti-apoptotic signals, autophagy, epithelial-mesenchymal transition, components of the non-coding genome or onco-mIRs, cancer stem cells and cellular invasiveness. The last two decades have revealed that each of these processes are also directly regulated by a component of the cell cycle apparatus, cyclin D1.

Area covered: The current review is provided to update recent developments in the clinical application of cyclin/CDK inhibitors to breast cancer with a focus on the anti-tumor immune response.

Expert opinion: The cyclin D1 gene encodes the regulatory subunit of a proline-directed serine-threonine kinase that phosphorylates several substrates. CDKs possess phosphorylation site selectivity, with the phosphate-acceptor residue preceding a proline. Several important proteins are substrates including all three retinoblastoma proteins, NRF1, GCN5, and FOXM1. Over 280 cyclin D3/CDK6 substrates have b\een identified. Given the diversity of substrates for cyclin/CDKs, and the altered thresholds for substrate phosphorylation that occurs during the cell cycle, it is exciting that small molecular inhibitors targeting cyclin D/CDK activity have encouraging results in specific tumors.  相似文献   

5.
目的探讨腹股沟疝一侧术后对侧发生腹股沟疝的时间间隔,并对其进行分析。方法回顾医院2012年5月—2019年9月收治的腹股沟疝患者37例,所有患者对侧均有腹股沟疝手术史,将2次发病的时间间隔分为3组,T≤2年为短期组,2相似文献   
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8.
目的 运用网状Meta分析方法评价针灸联合关节松动术治疗肩周炎的疗效。方法 运用计算机检索Web of Science、PubMed、Cochrane Library、EMbase、维普(VIP)、中国知网(CNKI)、万方(Wanfang)、中国生物医学文献数据库(CBM),搜寻有关针灸联合关节松动术治疗肩周炎的随机对照试验。所有研究人员均独立纳排文献、提录资料、风险评估,对符合质量标准的RCT研究采用Stata16.0和Review Manager 5.4软件进行分析。结果 共检索出6561篇文献,最终纳入37项研究,涉及10种针灸联合关节松动术方法。总样本量2890例,其中试验组1432例,对照组1458例。网状Meta分析所得结果表明:①在总有效率方面,最好的3种治疗方法为内热针联合组、温针联合组、动筋针联合组;②在降低VAS评分方面,最好的3种治疗方法为内热针联合组、动筋针联合组、针刀联合组。结论 针灸联合关节松动术治疗肩周炎疗效总体优于单独使用,且内热针联合组具有最佳的疗效。  相似文献   
9.
目的 探讨改良单图像法手工测量髌骨不稳患者胫骨结节-股骨滑车沟(tibial tuberosity-trochlear groove,TT-TG)间距的可行性。 方法 选取髌骨不稳患者30例。高年资手术医师A、B,使用改良单图像法手工测量髌骨不稳患者TT-TG间距,对比高资年影像学医师C,使用双图法测量髌骨不稳患者TT-TG间距。应用Cronbach′s alpha系数评价结果的可信度。应用组内相关系数(intraclass correlation coefficient,ICC)评价结果的可重复性。使用Bland-Altman分析图评价结果的一致性。 结果 高年资手术医师A、B使用改良单图像法手工测量髌骨不稳患者TT-TG间距分别和高年资影像学医师C使用双图法测量髌骨不稳患者TT-TG间距比较,Cronbach′s alpha系数分别为0.913和0.959,组内相关系数分别为0.913和0.958。Bland-Altman分析图显示,TT-TG间距差值(mm)的均值为-0.276(95%CI:-3.526~2.974)和0.143(95%CI:-3.110~3.397)。A、B医师之间使用改良单图像法手工测量髌骨不稳患者TT-TG间距比较,Cronbach′s alpha系数为0.891,组内相关系数为0.891。Bland-Altman分析图显示TT-TG间距差值(mm)的均值为-0.276(95%CI:-3.526~2.974)。 结论 改良单图像法手工测量髌骨不稳患者TT-TG间距操作简单,可以准确测量出髌骨不稳患者的TT-TG间距,该方法和双图法可以相互替换使用。  相似文献   
10.
目的 探讨术中电生理监护对椎管神经鞘瘤显微手术中的作用及意义,提高对椎管内神经鞘瘤的治疗水平。方法 回顾性分析65例术中电生理动态监护下,显微手术切除椎管内神经鞘瘤。结果 治愈60例(占92.3%),好转5例(占7.7%),无死亡;肿瘤全切62例,次全切除3例,全切率95.4%。结论 常规动态电生理监测下显微手术切除椎管神经鞘瘤,能保全脊髓神经的功能,减少副损伤,提高手术安全性;显微手术有助于提高肿瘤全切率,可有效减少术后复发。对影响脊柱稳定性的行脊柱融合内固定。  相似文献   
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