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41.
42.
Ochratoxin A (OTA) is a mycotoxin that mainly causes nephrotoxicity. The single nephrotoxicity of OTA exposure on glomeruli or renal tubule had been well documented, however, the comparison toxicity between it is still unclear. Here, C57BL/6 mice and two types of nephrocyte were treated with concentration-gradient OTA to explore its differentiation nephrotoxicity. Results showed that OTA induced nephrotoxicity in vivo and in vitro, manifested as the deteriorative kidney function in mice and the cut-down cell viability in nephrocyte. Besides, results of murine kidney pathological section and IC50 of two types nephrocyte indicated that OTA-induced toxicity in renal tubule was higher than its in glomeruli. In addition, OTA exposure induced autophagy signaling differentiation expression. It revealed that autophagy was implicated in OTA-induced differential nephrotoxicity in glomeruli and renal tubule. Altogether, we proved that OTA induces a differentiation nephrotoxicity in glomeruli and renal tubule, and it is related to autophagy differential regulation.  相似文献   
43.
《Drug discovery today》2022,27(8):2373-2385
Autophagy, an evolutionarily highly conserved cellular degradation process, plays the Janus role (either cytoprotective or death-promoting) in colorectal cancer, so the targeting of several key autophagic pathways with small-molecule compounds may be a new therapeutic strategy. In this review, we discuss autophagy-associated cell death pathways and key cytoprotective autophagy pathways in colorectal cancer. Moreover, we summarize a series of small-molecule compounds that have the potential to modulate autophagy-associated cell death or cytoprotective autophagy for therapeutic purposes. Taken together, these findings demonstrate the Janus role of autophagy in colorectal cancer, and shed new light on the exploitation of a growing number of small-molecule compounds to target autophagy in future cancer drug discovery.  相似文献   
44.
《Saudi Pharmaceutical Journal》2022,30(12):1791-1801
Noscapine hydrochloride (benzyl-isoquinoline antitussive alkaloid) is an opium derivative and generally used as a cough suppressant. Numerous studies on noscapine hydrochloride have reported that it has potent anti-inflammatory activity. However, the mechanisms by which it exerts an anti-inflammatory function is not well understood. Protein denaturation is the primary step that leads to the organ destruction and permanent arthritic disability. The above-mentioned facts provided the ground to plan this study using different in-vitro and in-vivo approaches. RT-qPCR and ELISA assays were used to assess the inflammatory markers related to protein denaturation in complete adjuvant persuaded rheumatism in Sprague - Dawley rats. The results were collected as paw volume and body weight changes, arthritic scoring and serum antioxidant enzymes assays. These findings demonstrated that all doses of noscapine hydrochloride (10, 20 and 40 mg/kg) studied in this study, significantly (p < 0.001) decreased the protein denaturation by preventing the increase in levels of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), nuclear factor-kB (NF-kB), cyclooxygenase-2 (COX-2) and prostaglandin E2. Noscapine hydrochloride significantly reduced the paw volume (p < 0.001), arthritic scoring and reversed the body mass as compared to arthritic control diseased rats.  相似文献   
45.
目的:观察右归饮对去卵巢血管钙化中谷氨酸受体变化的影响。方法:将40只远交群雌性大鼠(sprague dawley,SD)随机分为假手术组、模型组、低剂量组、高剂量组和辛伐他汀组,采用皮下注射华法令加维生素D3制备血管钙化模型,造模后,低剂量组、高剂量组分别给予右归饮浓缩液5.35 g/(kg·d)和16.05 g/(kg·d)灌胃,辛伐他汀组给予辛伐他汀混悬水溶液5.25 mg/(kg·d)灌胃,假手术组和模型组给予等量生理盐水,共12周;实验结束时采集血浆标本测定雌二醇及血脂四项,采用苏木精-伊红染色法(HE染色)观察动脉钙化的情况,并采用免疫印迹试验检测N-甲基-D-天门冬氨酸受体(NMDAR,NR)1蛋白的表达。结果 :模型组大鼠雌二醇、甘油三酯含量和NR1蛋白表达降低,P<0.05,低密度脂蛋白升高,P<0.05;高剂量组和低剂量组雌二醇、甘油三酯含量升高,NR1蛋白表达增加,P<0.05;高剂量组、低剂量组和辛伐他汀组低密度脂蛋白的含量降低,P<0.05;辛伐他汀组雌二醇无变化,P>0.05。结论:右归饮可抑制大鼠去卵巢血管钙化的形成,可能与提高雌激素水平和NR1蛋白的表达有关。  相似文献   
46.
《Research in microbiology》2014,165(6):420-428
Acid stress is one of the most serious threats that cyanobacteria have to face, and it has an impact at all levels from genome to phenotype. However, very little is known about the detailed response mechanism to acid stress in this species. We present here a general analysis of the gene regulatory network of Synechocystis sp. PCC 6803 in response to acid stress using comparative genome analysis and biocomputational prediction. In this study, we collected 85 genes and used them as an initial template to predict new genes through co-regulation, protein–protein interactions and the phylogenetic profile, and 179 new genes were obtained to form a complete template. In addition, we found that 11 enriched pathways such as glycolysis are closely related to the acid stress response. Finally, we constructed a regulatory network for the intricate relationship of these genes and summarize the key steps in response to acid stress. This is the first time a bioinformatic approach has been taken systematically to gene interactions in cyanobacteria and the elaboration of their cell metabolism and regulatory pathways under acid stress, which is more efficient than a traditional experimental study. The results also provide theoretical support for similar research into environmental stresses in cyanobacteria and possible industrial applications.  相似文献   
47.
BackgroundNutritional status during pregnancy and the effects of nutritional deficiencies on pregnancy outcomes after bariatric surgery is an important issue that warrants further study. The objective of this study was to investigate pregnancy outcomes and nutritional indices after restrictive and malabsorptive procedures.MethodsWe investigated pregnancy outcomes of 113 women who gave birth to 150 children after biliopancreatic diversion (BPD), Roux-en-Y gastric bypass (RYGB), and sleeve gastrectomy (SG) between June 1994 and December 2011. Biochemical indices and pregnancy outcomes were compared among the different types of surgery and to overall 20-year hospital data, as well as to 56 presurgery pregnancies in 36 women of the same group.ResultsAnemia was observed in 24.2% and 15.6% of pregnancies after BPD and RYGB, respectively. Vitamin B12 levels decreased postoperatively in all groups, with no further decrease during pregnancy; however, low levels were observed not only after BPD (11.7%) and RYGB (15.6%), but also after SG (13.3%). Folic acid levels increased. Serum albumin levels decreased in all groups during pregnancy, but hypoproteinemia was seen only after BPD. Neonates after BPD had significantly lower average birth weight without a higher frequency of low birth weight defined as<2500 g. A comparison of neonatal data between babies born before surgery and siblings born after surgery (AS) showed that AS newborns had lower average birth weight with no significant differences in body length or head circumference and no cases of macrosomia.ConclusionOur study showed reasonably good pregnancy outcomes in this sample population after all types of bariatric surgery provided nutritional supplement guidelines are followed. Closer monitoring is required in pregnancies after malabsorptive procedures especially regarding protein nutrition.  相似文献   
48.
目的通过比较冠心病患者药物洗脱支架植入前后血浆高敏C反应蛋白(hs-CRP)的变化,判断机体介入前后炎症状况,并随访不良心血管事件,分析炎症因子与主要不良心血管事件的关系。方法入选从2013年10月1日至2014年6月17日在北京大学第一医院心血管内科就诊并行冠状动脉介入治疗的冠心病患者,签署知情同意书,收集其临床资料和介入手术情况,采集其介入治疗前、介入治疗后1天及30天的血样标本,测定hs-CRP浓度,比较介入治疗前后hs-CRP的变化,介入治疗1年后电话随访所有入选患者,收集主要不良心血管事件的发生率。结果共入选资料完整的冠心病患者84例。介入治疗1天后血浆hs-CRP水平与术前无显著差异(10.00±24.81 mg/L比7.52±17.90 mg/L,P=0.409),介入治疗30天后血浆hs-CRP水平较术前明显降低(2.80±4.66mg/L比7.52±17.90 mg/L,P0.001),较术后1天亦显著降低(P0.001);介入治疗后1年内有16人发生主要不良心血管事件,有事件的患者术前hs-CRP水平高于无事件患者(10.38±19.40 mg/L比6.84±17.61 mg/L,P=0.018),但术后1天hs-CRP水平无显著差异(12.91±27.76 mg/L比9.32±24.24 mg/L,P=0.175),术后30天hsCRP水平亦无显著差异(3.54±5.98 mg/L比2.63±4.32 mg/L,P=0.316)。结论冠心病患者介入治疗前hsCRP水平与术后1年内主要不良心血管事件的发生率存在正相关。冠心病患者围手术期的炎症反应在介入治疗30天后逐渐消退,这种变化可通过hs-CRP的浓度变化得到反映。  相似文献   
49.

Introduction

Non-androgenic growth factors are involved in the growth regulation of prostate cancer (PCa).

Objective

This is the first Brazilian study to correlate, in a population of patients operated for PCa, PSA, total testosterone, insulin-like growth factor-I (IGF-I) and insulin-like growth factor-binding protein-3 (IGFBP-3) with Gleason score and to compare with a control group with benign prostate hyperplasia (BPH).

Materials and Methods

This retrospective single-center study included 49 men with previously diagnosed PCa and 45 with previously diagnosed BPH. PSA, testosterone, IGF-I, IGFBP-3 were determined in both groups.

Results

PSA and IGFBP-3 levels were significantly higher in the PCa group as compared to the BPH group (p<0.001 and p=0.004, respectively). There was a significant difference when we compared the PSA before surgery (p<0.001) and at the inclusion in the study (p<0.001) and IGFBP3 (0.016) among patients with Gleason <7, ≥7 and BPH. In the PCa group, PSA, testosterone, IGF-I and IGFBP-3 levels were comparable between Gleason <7 and ≥7.

Conclusions

Our data suggest that in localized PCa, the quantification of PSA and, not of IGF-1, may provide independent significant information in the aggressiveness. IGFBP-3 could be a biochemical marker of disease control in PCa patients.  相似文献   
50.
干扰素诱导的跨膜蛋白(IFITM)是一种近来发现的细胞内抗病毒蛋白家族,它能抑制多种有或者无胞膜病毒的复制而起到抗病毒作用;同时近期有研究显示IFITM3对人类多种肿瘤细胞及干细胞的迁移等起重要作用,但IFITM3在人类肿瘤发生、发展和扩散转移的作用机制尚不明确.本文主要对IFITM3蛋白在人类肿瘤的研究进展及未来的研究方向作一综述.  相似文献   
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