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21.
Metformin, a drug for type 2 diabetes mellitus, has shown therapeutic effects for various cancers. However, it had no beneficial effects on the survival rate of human malignant mesothelioma (HMM) patients. The present study was performed to elucidate the underlying mechanism of metformin resistance in HMM cells. Glucose‐starved HMM cells had enhanced resistance to metformin, demonstrated by decreased apoptosis and autophagy and increased cell survival. These cells showed abnormalities in mitochondria, such as decreased ATP synthesis, morphological elongation, altered mitochondrial permeability transition pore and hyperpolarization of mitochondrial membrane potential (MMP). Intriguingly, Mdr1 was significantly upregulated in mitochondria but not in cell membrane. The upregulated mitochondrial Mdr1 was reversed by treatment with carbonyl cyanide m‐chlorophenyl hydrazone, an MMP depolarization inducer. Furthermore, apoptosis and autophagy were increased in multidrug resistance protein 1 knockout HMM cells cultured under glucose starvation with metformin treatment. The data suggest that mitochondrial Mdr1 plays a critical role in the chemoresistance to metformin in HMM cells, which could be a potential target for improving its therapeutic efficacy.  相似文献   
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MicroRNAs (miRNAs) play important roles in prostate cancer development. However, it remains unclear how individual miRNAs contribute to the initiation and progression of prostate cancer. Here we show that a basal layer‐enriched miRNA is required for prostate tumorigenesis. We identify miR‐205 as the most highly expressed miRNA and enriched in the basal cells of the prostate. Although miR‐205 is not required for normal prostate development and homeostasis, genetic deletion of miR‐205 in a Pten null tumor model significantly compromises tumor progression and does not promote metastasis. In Pten null basal cells, loss of miR‐205 attenuates pAkt levels and promotes cellular senescence. Furthermore, although overexpression of miR‐205 in prostate cancer cells with luminal phenotypes inhibits cell growth in both human and mouse, miR‐205 has a minimal effect on the growth of a normal human prostate cell line. Taken together, we have provided genetic evidence for a requirement of miR‐205 in the progression of Pten null‐induced prostate cancer.  相似文献   
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We report a case of benign lymphoplasmacytic plaque (LPP) in a child. These asymptomatic erythematous papulonodular lesions are an emerging clinicopathological entity. Herein, we describe a previously unreported site for LPP lesions, namely, the volar wrist and the distal ipsilateral palm.  相似文献   
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张旖  李占军  张文龙 《中医学报》2020,35(6):1307-1311
目的:探讨疏血通脉汤联合傍针刺治疗中风后肩手综合征(shoulder-hand syndrome after stroke,SHSAS)的临床疗效,并观察其对患者上肢肢体痉挛程度、血液流变学以及上肢活动能力的影响。方法:110例痰瘀阻络型SHSAS患者按照随机数字表法分为对照组与联合组,每组55例。两组患者均给予神经内科常规药物和肢体功能康复训练治疗。对照组联合傍针刺法治疗,联合组在对照组治疗基础上给予疏血通脉汤。两组患者均以4周为1个疗程,治疗1个疗程。记录比较两组患者治疗前后上肢肢体痉挛程度(Ashworth)、上肢活动能力(FMA)、肩手综合征量表(shoulder hand syndrome scale,SHSS)、视觉模拟评分(visual simulation scoring,VAS)、中医证候评分,高切全血黏度、低切全血黏度、血浆黏度和血小板聚集率等血液流变学指标,并比较治疗效果。结果:联合组有效率为96.36%,对照组有效率为83.64%,两组患者有效率比较,差异有统计学意义(P0.05)。治疗后,联合组高切全血黏度、低切全血黏度、血浆黏度与血小板聚集率水平均低于对照组,差异有统计学意义(P0.05);联合组Ashworth评分低于对照组、上肢FMA评分高于对照组,差异有统计学意义(P0.05);联合组SHSS评分和中医证候评分均低于对照组,差异有统计学意义(P0.05);联合组VAS评分低于对照组,差异有统计学意义(P0.05)。结论:疏血通脉汤联合傍针刺治疗SHSAS患者疗效显著,能有效改善患者血液流变学,缓解疼痛程度和上肢痉挛,提高上肢活动能力。  相似文献   
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It is well recognized that the world population is ageing rapidly. Therefore, it is important to understand ageing processes at the cellular and molecular levels to predict the onset of age‐related diseases and prevent them. Recent research has focused on the identification of ageing biomarkers, including those associated with the properties of the Golgi apparatus. In this context, Golgi‐mediated glycosylation of proteins has been well characterized. Additionally, other studies show that the secretion of many compounds, including pro‐inflammatory cytokines and extracellular matrix–degrading enzymes, is modified during ageing, resulting in physical and functional skin degradation. Since the Golgi apparatus is a central organelle of the secretory pathway, we investigated its structural organization in senescent primary human dermal fibroblasts using confocal and electron microscopy. In addition, we monitored the expression of Golgi‐related genes in the same cells. Our data showed a marked alteration in the Golgi morphology during replicative senescence. In contrast to its small and compact structure in non‐senescent cells, the Golgi apparatus exhibited a large and expanded morphology in senescent fibroblasts. Our data also demonstrated that the expression of many genes related to Golgi structural integrity and function was significantly modified in senescent cells, suggesting a relationship between Golgi apparatus function and ageing.  相似文献   
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Radiodermatitis is one of the commonest side effects of radiotherapy. They are usually assessed by semi‐quantitative clinical scores, which are not validated and may be subject to inter‐observer variability. A few previous studies suggested that high‐frequency ultrasonography (HF‐USG) is useful in the assessment of the acute phase of radiation dermatitis in breast cancer patients. (a) To monitor skin changes by HF‐USG during the course of radiotherapy due to head and neck cancers, and (b) to determine whether there is any connection between skin sonograms and the skin scoring criteria. This prospective, observational study includes patients diagnosed with head and neck cancers, treated with radiotherapy or concomitant chemoradiation. The final analysis includes six patients. In every patient, the HF‐USG as well as dermatological assessment (target lesion score—TLS and CACE v. 4.0) were performed 4×: before, in the middle, day after, and 3 months after radiotherapy. There were significant differences between non‐irradiated skin thickness and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P < .0001), as well as between irradiated, unchanged skin thickness (TLS grade 0) and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P = .0002). There was no significant difference between non‐irradiated and irradiated, unchanged skin thickness (TLS grade 0; P = .9318). In four patients, we demonstrated subepidermal low echogenic band (SLEB). HF‐USG can be useful tool to noninvasive and objective assessment of skin changes during radiotherapy.  相似文献   
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