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91.
Cinnamaldehyde (CA) is an essential component of cinnamon (Cinnamomum cassia Presland), which is often used as a flavoring condiment in beverages, pastries, perfumes, etc. Cinnamon is also used as herbal medicine in China and Southeast Asia to treat rheumatoid arthritis. However, the molecular mechanism is unclear. In this study, we aim to investigate its anti-inflammatory effects against Rheumatoid arthritis (RA) using activated macrophages (Raw246.7) in vitro and adjuvant arthritis rats (AA) in vivo. The results demonstrated that CA significantly reduced synovial inflammation in AA rats, possibly due to suppression of the expressions of pro-inflammatory cytokines, especially the IL-1β. Further investigation found that CA also suppressed the activity of HIF-1α by inhibiting the accumulation of succinate in cytoplasm. As we know, the reduction of HIF-1α nucleation slows down IL-1β production, because HIF-1α activates the expression of NLRP3, which is involved in the assembly of inflammasome and processing of IL-1β. In addition, CA also inhibited the expression of the succinate receptor GPR91, which in turn inhibited the activation of HIF-1α. In conclusions, our results suggested that CA might be a potential therapeutic compound to relieve rheumatoid arthritis progress by suppressing IL-1β through modulating succinate/HIF-1α axis and inhibition of NLRP3.  相似文献   
92.
目的 探讨微小RNA-148a-3p(miR-148a-3p)对丝裂原活化蛋白激酶激酶激酶9(MAP3K9)的靶向调控作用及对胃癌细胞增殖和凋亡的影响。方法 向对数生长期胃癌细胞株MGC-803转染miR-148a-3p模拟物(mimics组)和阴性对照(NC组),以未转染的MGC-803细胞为对照组;采用实时定量PCR(QPCR)检测各组miR-148a-3p水平以评价转染效率,MTT法检测各组细胞增殖能力,流式细胞术检测各组细胞凋亡情况,分别采用QPCR和Western blotting检测Bcl-2、Bax、caspase-3及MAP3K9 mRNA和蛋白水平,同时采用双荧光素酶报告实验验证miR-148a-3p与MAP3K9的靶向作用关系。结果 QPCR结果显示,对照组、NC组和mimics组的miR-148a-3p水平分别为1.021±0.123、1.087±0.196和2.854±0.368,与对照组和NC组比较,mimics组的miR-148a-3p水平升高(P<0.05)。mimics组MGC-803细胞的增殖活力较其余两组减弱(P<0.05)。mimics组MGC-803细胞凋亡率为(15.2±1.6)%,高于对照组的(3.5±0.9%)%和NC组的(4.5±1.1)%,差异具有统计学意义(P<0.05)。与对照组和NC组比较,mimics组的MAP3K9和Bcl-2的mRNA和蛋白水平均下调,而Bax和caspase-3的mRNA和蛋白水平均上调(P<0.05);双荧光素酶报告实验证实MAP3K9是miR-148a-3p的直接作用靶点。结论 MiR-148a-3p可抑制胃癌细胞MGC-803的增殖并诱导其凋亡,可能通过靶向MAP3K9来发挥抑癌作用,调控miR-148a-3p/MAP3K9轴在胃癌防治中有一定应用前景。  相似文献   
93.
Benzophenone-3 is a putative endocrine disrupting chemical and common ingredient in sunscreens. The potential of endocrine disrupting chemicals to act as agonists or antagonists in critical hormonally regulated processes, such as mammary gland development and mammary tumorigenesis, demands evaluation of its potential in promoting breast cancer. This study identifies the effects of BP-3 on mammary tumorigenesis with high-fat diet during puberty versus adulthood in Trp53-null transplant BALB/c mice. Benzophenone-3 exposure yielded levels in urine similar to humans subjected to heavy topical sunscreen exposure. Benzophenone-3 was protective for epithelial tumorigenesis in mice fed lifelong low-fat diet, while promotional for epithelial tumorigenesis in mice fed adult high-fat diet. Benzophenone-3 increased tumor cell proliferation, decreased tumor cell apoptosis, and increased tumor vascularity dependent on specific dietary regimen and tumor histopathology. Even in instances of an ostensibly protective effect, other parameters suggest greater risk. Although benzophenone-3 seemed protective on low-fat diet, spindle cell tumors arising in these mice showed increased proliferation and decreased apoptosis. This points to a need for further studies of benzophenone-3 in both animal models and humans as a potential breast cancer risk factor, as well as a more general need to evaluate endocrine disrupting chemicals in varying dietary contexts.  相似文献   
94.
目的讨论思考丙酸氟替卡松、硫酸沙丁胺醇吸入联合维生素D3治疗小儿变异性哮喘的临床效果。方法抽选于2018年12月-2019年12月期间本院儿科门诊共收治的小儿变异性哮喘患儿72例入组,根据计算机随机分组法均分为两组。对照组(n=36)给予丙酸氟替卡松联合硫酸沙丁胺醇吸入治疗,研究组(n=36)给予丙酸氟替卡松、硫酸沙丁胺醇吸入联合维生素D3治疗。评价及对比两组的疗效、T淋巴细胞含量、血清生化指标。结果研究组的疗效高于对照组(P<0.05);研究组的血清生化指标均优于对照组(P<0.05);研究组的CD4^+、CD4^+/CD8^+含量低于对照组,且CD8^+含量高于对照组(P<0.05)。结论丙酸氟替卡松、硫酸沙丁胺醇吸入联合维生素D3治疗小儿变异性哮喘,疗效确切,可协同增效、相互补充,缓解症状,维持T淋巴细胞亚群平衡,减轻炎症反应,值得临床借鉴应用。  相似文献   
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BackgroundColorectal cancer (CRC) is the primary cause of cancer-related deaths worldwide. Identification of new CRC biomarkers is imperative to improve the prognosis and development of therapies against the disease. LAGE3 (L Antigen Family Member 3) functions as a tRNA modifier, although its potential role in CRC has not been fully elucidated.MethodsRNA-seq matrix and corresponding clinical information were downloaded from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases, then subjected to survival, enrichment, and tumor microenvironment analyses using packages implemented in R.ResultsWe found that LAGE3 was upregulated and significantly correlating with poor prognosis in multiple CRC cohorts. Additionally, multivariate Cox regression analysis revealed that LAGE3 was an independent prognostic factor in patients with CRC, whereas functional enrichment analysis indicated that it could regulate protein targeting, tRNA processing, and the PD-1/PD-L1 checkpoint pathway. Furthermore, CIBERSORT analysis indicated a negative relationship between LAGE3 and levels of infiltration for multiple immune cells, especially CD8 + T cells in CRC. Particularly, LAGE3 expression was inversely correlated with the expression of immune checkpoints as well as that of various immune cell types of signature genes.ConclusionCollectively, our results indicate that high LAGE3 expression correlates with adverse prognosis and poor immune infiltration in CRC patients.  相似文献   
98.
目的:以灰毡毛忍冬为材料,克隆对-香豆酸3-羟化酶(LmC3H1)基因,进行生物信息学和表达模式分析,结合绿原酸含量,研究推测灰毡毛忍冬LmC3H1基因的功能。方法:通过逆转录聚合酶链式反应(RT-PCR)和RACE技术克隆LmC3H1基因的全长c DNA序列,对该序列进行生物信息学分析,并利用实时荧光定量PCR(Real-time PCR)和HPLC分别测定灰毡毛忍冬茎、叶及不同花期花中LmC3H1的相对表达量及绿原酸含量。结果:克隆得LmC3H1(Gen Bank:MN177695)基因,开放阅读框(ORF)长度为1 533 bp,编码510个氨基酸,推测其分子式为C_(2618)H_(4134)N_(718)O_(727)S_(22),相对分子质量为58 005.32,等电点8.92,为亲水性蛋白,定位于叶绿体中,具有跨膜区域LLLIPAVLFLISLVYPLI,含有细胞色素P450的保守结构域CYTOCHROME_P450(422-433 aa);Real-time PCR结果显示,LmC3H1在灰毡毛忍冬茎、叶及不同花期花有不同程度的表达,其中在花发育阶段,白色花蕾期相对表达量最高,花蕾初期及白色开花期次之;白色花蕾期花与茎、叶比,花的相对表达量最高,叶的最低;HPLC结果显示,从绿白色花蕾期到金黄色开花期绿原酸含量呈上升趋势,金黄色开花期含量最高,不同器官中,花中绿原酸最高,茎最低。结论:克隆得到灰毡毛忍冬LmC3H1基因,推测LmC3H1可能参与灰毡毛忍冬花绿原酸的生物合成。该研究为进一步研究该基因的功能及探究灰毡毛忍冬绿原酸生物合成和调节机制提供了依据,同时为遗传改良灰毡毛忍冬品质奠定了基础。  相似文献   
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Reports on pediatric low-grade diffuse glioma WHO-grade II (DG2) suggest an impaired survival rate, but lack conclusive results for genetically defined DG2-entities. We analyzed the natural history, treatment and prognosis of DG2 and investigated which genetically defined sub-entities proved unfavorable for survival. Within the prospectively registered, population-based German/Swiss SIOP-LGG 2004 cohort 100 patients (age 0.8-17.8 years, 4% neurofibromatosis [NF1]) were diagnosed with a DG2. Following biopsy (41%) or variable extent of resection (59%), 65 patients received no adjuvant treatment. Radiologic progression or severe neurologic symptoms prompted chemotherapy (n = 18) or radiotherapy (n = 17). Multiple lines of salvage treatment were necessary for 19/35 patients. Five years event-free survival dropped to 0.44, while 5 years overall survival was 0.90 (median observation time 8.3 years). Extensive genetic profiling of 65/100 DG2 identified Histone3-K27M-mutation in 4, IDH1-mutation in 11, BRAF-V600-mutation in 12, KIAA1549-BRAF-fusions in 6 patients, while the remaining 32 tumor tissues did not show alterations of these genes. Progression to malignant glioma occurred in 12 cases of all genetically defined subgroups within a range of 0.5 to 10.8 years, except for tumors carrying KIAA1549-BRAF-fusions. Histone3-K27M-mutant tumors proved uniformly fatal within 0.6 to 2.4 years. The current LGG treatment strategy seems appropriate for all DG2-entities, with the exemption of Histone3-K27M-mutant tumors that require a HGG-related treatment strategy. Our data confirm the importance to genetically define pediatric low-grade diffuse gliomas for proper treatment decisions and risk assessment.  相似文献   
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