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排序方式: 共有5448条查询结果,搜索用时 31 毫秒
1.
目的:研究柴胡皂苷D(saikosaponin-D,SSD)对人结直肠癌细胞SW480迁移和侵袭能力的影响,并初步探讨SSD抑制细胞迁移和侵袭的机制。方法:MTT检测SSD对细胞增殖的影响。划痕实验和Transwell迁移实验研究SSD对细胞迁移能力的影响。Transwell侵袭实验研究SSD对细胞侵袭能力的影响。Western-blot检测SSD对上皮间质转化(epithelial mesenchymal transformation,EMT)相关蛋白(E-cadherin、N-cadherin和Vimentin)表达的影响。克隆球形成实验研究SSD对细胞干性的影响。结果:在划痕实验和Transwell迁移实验中,SSD显著抑制SW480的迁移能力(P<0.05)。在Transwell侵袭实验中,SSD显著抑制SW480的侵袭能力(P<0.05)。SSD处理后,细胞E-cadherin的表达增高,N-cadherin和Vimentin的表达降低(P<0.05),同时SSD抑制SW480细胞克隆球的形成(P<0.05)。结论:柴胡皂苷D通过抑制EMT和细胞干性抑制人结直肠癌细胞SW480的迁移和侵袭。 相似文献
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Xiuhua Weng Shaohong Luo Shen Lin Lixian Zhong Meiyue Li Rao Xin Pinfang Huang Xiongwei Xu 《Oncology research》2020,28(2):117-125
To evaluate the cost–utility of pembrolizumab versus chemotherapy as the first-line setting for metastatic nonsmall cell lung cancer (NSCLC) from the US health care system perspective, a Markov model was developed
to compare the lifetime cost and effectiveness of pembrolizumab versus chemotherapy for untreated metastatic NSCLC, based on the clinical data derived from phase III randomized controlled trial (KEYNOTE-
042; ClinicalTrials.gov; NCT02220894). Weibull distribution was fitted to simulate the parametric survival
functions. Drug costs were collected from official websites, and utility values were obtained from published literature. Total costs, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratios
(ICERs) were computed as primary output indicators. The impact of different PD-L1 expression levels
on ICER was also evaluated. One-way and probabilistic sensitivity analyses were performed to assess the
model uncertainty. Compared with chemotherapy, patients treated with pembrolizumab provided an additional 1.13, 1.01, and 0.59 QALYs in patients with PD-L1 expression levels of ≥50%, ≥20%, and ≥1%,
with corresponding incremental cost of $53,784, $47,479, and $39,827, respectively. The resultant ICERs
of pembrolizumab versus chemotherapy were $47,596, $47,184, and $68,061/QALY, in three expression
levels of PD-L1, respectively, all of which did not exceed the WTP threshold of 180,000/QALY. Probability
sensitivity analysis outcome supported that pembrolizumab exhibited evident advantage over chemotherapy
to be cost-effective. One-way sensitivity analysis found that ICERs were most sensitive to utility value of
pembrolizumab in progression survival state. All the adjustment of parameters did not qualitatively change
the result. For treatment-naive, metastatic NSCLC patients with PD-L1+, pembrolizumab was estimated
to be cost-effective compared with chemotherapy for all PD-L1 expression levels at a WTP threshold of
$180,000/QALY in the context of the US health care system. 相似文献
4.
目的:研究柴胡皂苷D(saikosaponin-D,SSD)对人结直肠癌细胞SW480自噬的影响,并探讨诱导的自噬对细胞增殖的影响。方法:Western-blot检测SSD对自噬相关蛋白LC3A/B和p62表达的影响,LC3翻转实验和GFP-RFP-LC3荧光实验验证自噬流的发生。Western-blot检测3-MA对SSD所诱导自噬的抑制作用,MTT和细胞计数实验研究3-MA抑制自噬后SSD对SW480细胞增殖的影响。结果:SSD能够诱导SW480细胞发生自噬,表现在LC3A/B II及LC3A/B II/I比值的增高、自噬经典底物蛋白p62的减少、LC3翻转试验阳性以及LC3荧光实验中黄色和红色荧光颗粒的增多(P<0.05)。自噬抑制剂3-MA能够抑制SSD所诱导自噬的发生(P<0.05),且3-MA抑制自噬后,SSD对SW480的增殖抑制效应减弱(P<0.05),提示SSD诱导的自噬对细胞的增殖起抑制作用。结论:SSD通过诱导自噬抑制人结直肠癌细胞SW480的增殖。 相似文献
5.
Recurrent BRCA1 Mutation,but no BRCA2 Mutation,in Vietnamese Patients with Ovarian Carcinoma Detected with Next Generation Sequencing 下载免费PDF全文
Hoang Anh VuNgo Dai PhuLe Thai KhuongPham Huy HoaBui Thi Hong NhuVo Thanh NhanLe Quang ThanhNguyen Duy SinhHoang Thanh ChiNguyen Dang QuanNguyen Trong Binh 《Asian Pacific journal of cancer prevention》2020,21(8):2331-2335
Background: Identification of germline and somatic BRCA1/2 mutations in ovarian cancer is important for genetic counseling and treatment decision making with poly ADP ribose polymerase inhibitors. Unfortunately, data on the frequency of BRCA1/2 mutations in Vietnamese patients are scare. Methods: We aim to explore the occurrence of BRCA1/2 mutations in 101 Vietnamese patients with ovarian cancer including serous (n = 58), endometrioid (n = 14), mucinous (n = 24), and clear cell (n = 5) carcinomas. BRCA1/2 mutations were detected from formalin-fixed parafin-embedded tumor samples using the OncomineTM BRCA Research Assay on Personal Genome Machine Platform with Ion Reporter Software for sequencing data analysis. The presence of pathogenic mutations was confirmed by Sanger sequencing. Results: We found no BRCA2 mutation in the entire cohort. Four types of pathogenic mutations in BRCA1 (Ser454Ter, Gln541Ter, Arg1751Ter, and Gln1779AsnfsTer14) were detected in 8 unrelated patients (7.9%) belonging to serous and endometrioid carcinoma groups. Except for the c.1360_1361delAG (Ser454Ter) mutation in BRCA1 exon 11 that was somatic, the other mutations in exons 11, 20, and 22 were germline. Interestingly, the recurrent Arg1751Ter mutation in BRCA1 exon 20 appeared in 4 patients, suggesting that this is a founder mutation in Vietnamese patients. Conclusion: Mutational analysis of tumor tissue using next generation sequencing allowed the detection of both germline and somatic BRCA1/2 mutations. 相似文献
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Xiang Yu Ben Wang ShaoMin Yang SongBo Han Liang Jiang XiaoGuang Liu Feng Wei FengLiang Wu Lei Dang ZhongJun Liu 《The spine journal》2019,19(3):509-515
BACKGROUND CONTEXT
Both open surgical resection (OSR) and radiofrequency ablation (RFA) have been reported for spinal osteoid osteoma (OO).PURPOSE
To verify the clinical safety and efficiency of RFA with OSR in treating spinal OO.STUDY DESIGN
Retrospective cohort study.PATIENT SAMPLE
Twenty-eight consecutive patients with spinal OO who underwent either RFA or OSR in our institute between September 2006 and December 2016.OUTCOME MEASURES
The age, gender, lesion distribution, surgical time, estimated blood loss, complications, local recurrence, visual analogue scale (VAS), and the modified Frankel grade were documented.METHODS
We retrospectively reviewed 28 patients with spinal OO who had been treated in our hospital from September 2006 to December 2016. Patients were followed at 3, 6, 12, and 24 months after the index surgery. The minimum follow-up period was 12 months. This study was funded by Peking University Third Hospital (Y71508-01) (¥ 400,000).RESULTS
Twelve and 16 patients were treated with CT-guided percutaneous RFA and OSR, respectively. Spinal OO locations were cervical in 4, thoracic in 4, lumbar in 3, and sacral vertebra in 1 in the RFA group and cervical in 12, thoracic in 1, and lumber in 3 in the OSR group. RFA showed shorter operating time, less blood loss, and less in-hospital stay than open surgery [105.0 ± 33.8 minutes vs. 186.4 ± 53.5 minutes (p < .001), 1 (0 to 5) ml vs. 125 (30–1200) ml (p < .001) and 1 (1–3) days vs. 6 (3–10) days (p < .001), respectively]. At last follow-up, one patient underwent a secondary RFA for recurrence. VAS improvement was 7.5 (3–10) and 6.5 (4–9) (p = .945) in the RFA and OSR groups, respectively. The overall complication rate was 8.3% (1/12) and 18.8% (3/16) in the RFA and OSR groups, respectively.CONCLUSIONS
If there is sufficient cerebrospinal fluid between the spinal OO lesion and spinal cord/nerve root (more than 1 mm), RFA is effective and safe for treatment of well-selected spinal OO, showing reduced operating time, blood loss, in-hospital stay, and complications compared to OSR. However, OSR is still recommended in cases with spinal cord/nerve root compression. 相似文献8.
Farah Ladak Jerry T. Dang Noah J. Switzer Valentin Mocanu Daniel W. Birch Shahzeer Karmali 《Surgery for obesity and related diseases》2019,15(3):431-440
BackgroundComplications arising from laparoscopic Roux-en-Y gastric bypass (LRYGB) and laparoscopic sleeve gastrectomy (LSG) are not insignificant and can necessitate additional invasive interventions or reoperations.ObjectivesIn this study, we identify early complications that result in nonoperative and operative interventions after LSG and LRYGB, the timeframe within which to expect them, and factors that influence the likelihood of their occurrence.SettingMulti-institutional database from across North America.MethodsData for this study were obtained from Metabolic and Bariatric Accreditation and Quality Improvement Program participant use files for 2015 and 2016. Statistical analysis was performed using STATA 15. Univariate analysis using Χ2 for categoric data and independent t test for continuous data was performed to determine between group differences. Multivariable logistic regression analysis was used to identify predictors of operative and nonoperative reinterventions.ResultsIn 2015 and 2016, 243,747 underwent LRYGB or LSG, of which 3013 (1.24%) required a second operative procedure and 1536 (0.63%) required an invasive but nonoperative intervention. Complications occurred in 5.48% of LRYGB patients and 2.28% of LSG patients, the most common of which was bleeding. LSG was associated with far fewer nonoperative and operative interventions (.85% versus 2.2%, respectively) than LRYGB (.67% versus 2.5%). Renal insufficiency, including dialysis dependency, was an important predictor of reoperations among bariatric surgery patients. This was also true of nonoperative interventions; however, history of pulmonary embolism, and use of therapeutic anticoagulation were marginally stronger predictors.ConclusionsIn a representative, multinational sample, operative and nonoperative interventions were half as likely among LSG patients compared with LRYGB; however, overall rates still remained low. These findings, in conjunction with new efficacy data demonstrating comparable long-term weight loss between LRYGB and LSG, provide further support for the safety, effectiveness, and cost efficiency of LSG. 相似文献
9.
P38 and JNK signal pathways are involved in the regulation of phlorizin against UVB‐induced skin damage 下载免费PDF全文
Yimiao Zhai Yongyan Dang Wenke Gao Ye Zhang Peng Xu Jun Gu Xiyun Ye 《Experimental dermatology》2015,24(4):275-279
Phlorizin is well known to inhibit sodium/glucose cotransporters in the kidney and intestine for the treatment of diabetes, obesity and stress hyperglycaemia. However, the effects of phlorizin against ultraviolet B (UVB) irradiation and its molecular mechanism are still unknown. We examined the effects of phlorizin on skin keratinocyte apoptosis, reactive oxygen species (ROS) production, pro‐inflammatory responses after UVB irradiation and the changes of some signal molecules by in vitro and in vivo assay. We observed that phlorizin pretreatments inhibited HaCaT cell apoptosis and overproduction of ROS induced by UVB. Phlorizin also decreased the expression of UVB‐induced pro‐inflammatory cytokines, such as interleukin‐1 beta (IL‐1β), interleukin‐6 (IL‐6) and interleukin‐8 (IL‐8) at the mRNA level. Topical application of phlorizin on UVB‐exposed skin of nude mice prevented the formation of scaly skin and erythema, inhibited the increase of epidermal thickness and reduced acute inflammation infiltration in skin. Additionally, PCR, Western blot and immunohistochemical data showed that phlorizin reversed the overexpression of cyclooxygenase‐2 (Cox‐2) induced by UVB irradiation both in vitro and in vivo. The activation of p38 and JNK mitogen‐activated protein kinases (MAPK) after UVB irradiation was also inhibited by phlorizin. These findings suggest that phlorizin is effective in protecting skin against UVB‐induced skin damage by decreasing ROS overproduction, Cox‐2 expression and the subsequent excessive inflammation reactions. It seemed that p38 and JNK MAPK signal pathways are involved in the regulation of the protective function of phlorizin. 相似文献
10.
Payel Sen Weiwei Dang Greg Donahue Junbiao Dai Jean Dorsey Xiaohua Cao Wei Liu Kajia Cao Rocco Perry Jun Yeop Lee Brian M. Wasko Daniel T. Carr Chong He Brett Robison John Wagner Brian D. Gregory Matt Kaeberlein Brian K. Kennedy Jef D. Boeke Shelley L. Berger 《Genes & development》2015,29(13):1362-1376