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71.
目的研究羌活Notopterygium incisum的香豆素类成分及其抗炎活性。方法采用硅胶、HPLC等柱色谱方法进行分离纯化,通过质谱、核磁共振波谱数据鉴定化合物的结构;采用脂多糖(LPS)诱导的小鼠巨噬细胞RAW 264.7炎症反应模型,考察羌活中香豆素类成分对炎症反应模型一氧化氮(NO)生成的影响。结果从羌活甲醇提取物分离得到24个香豆素类化合物,分别鉴定为异欧前胡素(1)、川白芷素(2)、补骨脂素(3)、香柑内酯(4)、茵陈素(5)、欧芹酚(6)、5-去氢羌活醇(7)、环氧脱水羌活醇(8)、7″-O-甲基异羌活醇(9)、佛手柑素(10)、7-异戊烯氧基-6-甲氧基-香豆素(11)、栓翅芹烯醇(12)、羌活醇(13)、去甲呋喃羽叶芸香素(14)、异羌活醇(15)、蛇床夫内酯(16)、6-异戊烯氧基伞形花内酯(17)、紫花前胡苷元(18)、异虎耳草素(19)、紫花前胡苷(20)、前胡苷V(21)、前胡苷I(22)、印枳苷元-11-O-β-D-吡喃葡萄糖基-(1→6)-β-D-吡喃葡萄糖苷(23)、羌活苷(24)。化合物7~10、13和15抑制LPS诱导的RAW 264.7细胞NO生成活性最强,最大半数抑制浓度(IC_(50))值为8.50~35.12μmol/L。结论化合物7为新的天然产物,化合物17为首次从羌活中分离得到;C-5位上具有多烯烃结构的香豆素抑制LPS诱导的RAW 264.7细胞NO生成活性较强。 相似文献
72.
Inflammation plays a critical role in the development of ventilator-induced lung injury (VILI). Endoplasmic reticulum (ER) stress is associated with a variety of diseases through the modulation of inflammatory responses. However, little is known about how ER stress is implicated in VILI. In this study, murine mechanical ventilation models were constructed. Total protein and inflammatory cytokines were measured in bronchoalveolar lavage fluid (BALF), and lung tissue injury was assessed by histology. Our data revealed that mice subjected to high tidal ventilation (TV) for 4 h showed more severe pulmonary edema and inflammation than those of mice with spontaneous breathing and low TV-treatment. In addition, the high TV-treated animals upregulated the ER stress markers GRP78, CHOP, p-IRE1α, TRAF2, and p-NF-κB expression at both the mRNA and protein levels in lung tissue. Administration of thapsigargin exacerbated the histological changes, inflammation and expression of GRP78 and CHOP after high TV, but treatment with ER stress and IRE1α kinase inhibitors attenuated the pathological damage and downregulated the high expression of GRP78, CHOP, p-IRE1α, TRAF2, and p-NF-κB, suggesting that ER stress is involved in VILI though the IRE1α/TRAF2/NF-κB signaling pathway in mice. 相似文献
73.
Sirt5 is known to functionally regulate mitochondrial proteins by altering posttranslational modifications, including lysine desuccinylation. While roles for Sirt5 as either a tumor promoter or suppressor, or in chemoresistance, have been implicated in other cancers, the function of Sirt5 in cutaneous melanoma has not been well examined. Therefore, to determine whether Sirt5 is necessary for BrafV600E‐mediated melanoma formation and/or disease progression, we crossed a genetically engineered murine melanoma model (TyrCreERT2/+; BrafLSL‐V600E/+; Ptenflox/flox) to Sirt5?/? knockout animals. In addition, we tested for synergism with a selective BRAF (V600E) inhibitor in Sirt5?/? mouse melanoma cells. Taken together, this report demonstrates that, in these models, Sirt5 is dispensable for BrafV600E‐mediated cutaneous melanoma formation and growth in vivo, and does not improve sensitivity to a selective BRAF inhibitor. 相似文献
74.
75.
目的探讨重睑术中采用经重睑切口的上睑旋转皮瓣矫正轻、中度内眦赘皮的疗效。方法回顾分析 2016 年 7 月—2017 年 10 月,重睑术中采用经重睑切口的上睑旋转皮瓣矫正轻、中度睑板型内眦赘皮合并单睑的 34 例患者(试验组)临床资料;以同期 38 例接受传统“Z”成形内眦开大术联合重睑术患者为对照(对照组)。两组患者年龄及内侧赘皮分度比较,差异无统计学意义(P>0.05)。于术前及术后 6 d、6 个月测量眼裂长度,计算眼裂长度改善程度;参照内眦赘皮矫正标准评价手术疗效。 结果两组患者切口均Ⅰ期愈合,并获随访 6 个月。两组内眦赘皮明显矫正。试验组内眦处无切口;对照组遗留瘢痕,其中 6 例增生明显。术后 6 d 试验组及对照组眼裂长度改善程度分别为 3.63%±0.07%、3.70%±0.05%;术后 6 个月分别为 4.64%±0.09%、4.46%±0.10%;两组比较差异均无统计学意义(t=0.005,P=0.996;t=0.287,P=0.871)。术后 6 个月疗效评价,试验组优 20 例、良 12 例、差 2 例,优良率 94.12%;对照组优 16 例、良 16 例、差 6 例,优良率 84.21%;差异无统计学意义(χ2=0.796,P=0.372)。 结论经重睑切口的上睑旋转皮瓣矫正轻、中度内眦赘皮手术操作简便、效果满意,内眦处无瘢痕形成。 相似文献
76.
Jinlan He Jianxiong He Li Min Yan He Hui Guan Jingjing Wang Xingchen Peng 《International journal of cancer. Journal international du cancer》2020,146(4):1052-1063
Sorafenib provides survival benefits in patients with advanced renal cell carcinoma (RCC), but its use is hampered by acquired drug resistance. It is important to fully clarify the molecular mechanisms of sorafenib resistance, which can help to avoid, delay or reverse drug resistance. Extracellular vesicles (EVs) can mediate intercellular communication by delivering effector molecules between cells. Here, we studied whether EVs are involved in sorafenib resistance of RCC and its possible molecular mechanisms. Using differential centrifugation, EVs were isolated from established sorafenib-resistant RCC cells (786-0 and ACHN), and EVs derived from sorafenib-resistant cells were uptaken by sensitive parental RCC cells and thus promoted drug resistance. Elevated exogenous miR-31-5p within EVs effectively downregulated MutL homolog 1 (MLH1) expression and thus promoted sorafenib resistance in vitro. Mice experiments also confirmed that miR-31-5p could mediate drug sensitivity in vivo. In addition, low expression of MLH1 was observed in sorafenib-resistant RCC cells and upregulation of MLH1 expression restored the sensitivity of resistant cell lines to sorafenib. Finally, miR-31-5p level in circulating EVs of RCC patients with progressive disease (PD) during sorafenib therapy was higher when compared to that in the pretherapy status. In conclusion, EVs shuttled miR-31-5p can transfer resistance information from sorafenib-resistant cells to sensitive cells by directly targeting MLH1, and thus magnify the drug resistance information to the whole tumor. Furthermore, miR-31-5p and MLH1 could be promising predictive biomarkers and therapeutic targets to prevent sorafenib resistance. 相似文献
77.
78.
驱动基因的发现及针对驱动基因的靶向治疗已显著提高了肺癌患者的生存质量和时间,但目前对于BRAF、HER2、MET、RET等少见驱动基因改变肺癌患者的靶向药物的选择仍然较少。近年来免疫检查点抑制剂在肺癌治疗中取得了一定的疗效,但因为少见驱动基因突变的肺癌患者本身样本量少,开展大规模临床随机对照试验尚存在一定的困难,目前此类患者接受免疫检查点抑制剂治疗的疗效情况仍不明确。本文将对目前已掌握的免疫检查点抑制剂治疗BRAF、HER2、MET、RET等少见驱动基因改变肺癌患者的临床研究结果进行综述,以期在一定程度上为临床工作提供一些依据和参考。 相似文献
79.
目的观察化浊清解愈溃煎对溃疡性结肠炎(UC)大鼠血清及结肠组织p38MAPK、肿瘤坏死因子-α(TNF-α)、白细胞介素-4(IL-4)含量的影响。方法清洁级Wistar雄性大鼠50只按随机数字表法分为两组,空白组8只,其余大鼠均为造模组。采用TNBS/乙醇联合造模法构建UC大鼠模型。造模成功后按照随机数字表法将模型大鼠分为模型组、西药组(予美沙拉嗪肠溶片混悬液0.42 g/kg)及中药高、中、低剂量组。中药高、中、低剂量组予化浊清解愈溃煎中药混悬液,剂量分别为22、11、5.5 g/(kg·d),每日灌胃1次,疗程14 d。采用免疫组化法检测各组大鼠结肠组织内p38MAPK的蛋白表达量。ELISA法检测各组大鼠血清内TNF-α、IL-4含量。结果与空白组比较,模型组一般情况较差,血清中TNF-α含量显著升高(P<0.05),IL-4含量则明显降低(P<0.05),结肠组织中p38MAPK水平明显升高(P<0.05)。与模型组比较,西药组、中药各剂量组大鼠一般生存状况改善明显,血清中TNF-α含量下降,IL-4含量明显升高,尤以中药高剂量组和西药组疗效显著(P<0.05)。结论化浊清解愈溃煎高、中剂量可改善UC大鼠一般生存状况,并通过调节血清中IL-4含量,下调TNF-α表达水平和结肠组织中p38MAPK蛋白表达水平而达到保护结肠黏膜和治疗UC的作用。 相似文献
80.
《Taiwanese journal of obstetrics & gynecology》2020,59(2):334-337
ObjectiveWe present prenatal diagnosis of mosaicism for a distal 5p deletion in a single colony at amniocentesis with a favorable outcome, and we review the literature of mosaic distal 5p deletion.Case ReportA 35-year-old primigravid woman underwent amniocentesis at 18 weeks of gestation because of advanced maternal age. Amniocentesis revealed the result of 46,XY,del(5)(p13)[1]/46,XY[19]. Among 20 colonies of cultured amniocytes, all four cells in one colony had a karyotype of 46,XY,del(5)(p13) with a distal deletion of 5p13→pter, while the rest 19 colonies had a karyotype of 46,XY. Repeat amniocentesis was performed at 21 weeks of gestation. Conventional cytogenetic analysis revealed a karyotype of 46,XY in all 20 colonies. Simultaneous array comparative genomic hybridization (aCGH) using the DNA extracted from the uncultured amniocytes revealed no genomic imbalance. Prenatal ultrasound findings were unremarkable. At 38 weeks of gestation, a 3621-g male baby was delivered with no phenotypic abnormality. The cord blood had a karyotype of 46,XY. Postnatal urinary cells analysis by interphase fluorescence in situ hybridization (FISH) using a 5p terminal FISH probe detected no abnormal cell in the urine.ConclusionMosaicism for a distal 5p deletion in a single colony at amniocentesis can be associated with a favorable outcome. 相似文献