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1.
Hui Fan Xianzhen Jin Chunyan Liao Lina Qiao Wei Zhao 《Pathology, research and practice》2019,215(11):152667
MicroRNAs (miRNAs) have been found to be aberrantly expressed and exert essential roles in the tumorigenesis and progression of gastric cancer (GC). miR-301b-3p has been recognized as a cancer-related miRNA in lung cancer, bladder cancer and hepatocellular carcinoma. However, the function of miR-301b-3p in GC progression and its underlying mechanism have not been studied yet. In this study, we found that miR-301b-3p expression was up-regulated in GC tissues compared to adjacent noncancerous tissues. Furthermore, the elevated levels of miR-301b-3p were detected in GC cell lines (SGC-7901, AGS, MKN-45 and MGC-803) as compared with GES-1 cells. Interestingly, GC tissues from patients with tumor size ≥ 5 cm and advanced tumor stages showed obvious higher levels of miR-301b-3p compared to matched controls. Functionally, miR-301b-3p knockdown prominently inhibited cell proliferation, and induced cell cycle arrest at G1 phase and apoptosis in MGC-803 cells. Meanwhile, ectopic expression of miR-301b-3p conversely regulated these biological behaviors of MKN-45 cells. Next, we found that miR-301b-3p knockdown increased, whereas miR-301b-3p overexpression reduced the expression of zinc finger and BTB domain containing 4 (ZBTB4) in GC cells. Accordingly, luciferase reporter assay identified ZBTB4 as a direct target of miR-301b-3p. ZBTB4 overexpression markedly restrained the growth of MGC-803 cells. More importantly, ZBTB4 silencing partially reversed miR-301b-3p knockdown-induced tumor suppressive effects on MGC-803 cells. In conclusion, we firstly revealed that miR-301-3p was highly expressed in GC and contributed to tumor progression via attenuating ZBTB4, which might provide a novel molecular-targeted strategy for GC treatment. 相似文献
2.
The impact of age on prognosis in patients with gastric cancer: experience in a tertiary care centre
Maan El Halabi Renee Horanieh Hani Tamim Deborah Mukherji Sara Jdiaa Sally Temraz Ali Shamseddine Kassem Barada 《Journal of gastrointestinal oncology.》2020,11(6):1233
BackgroundGastric cancer (GC) is a leading cause of cancer-related death in the world and most patients have advanced disease upon presentation. The effect of age on prognosis in GC is controversial. We aimed to determine the impact of age on survival in patients with GC.MethodsThis was a retrospective study of the medical records of Lebanese patients diagnosed with GC at the American University of Beirut Medical Center (AUBMC) between 2005 and 2014. Patients were divided into young (<65 years) and older groups (≥65 years). A multivariate analysis was done to determine the independent predictors of survival. Kaplan-Meier method was used for analysis of long-term survival outcomes.ResultsThe sample consisted of 156 patients. The mean age was 62.15 (SD 13.54). Most patients presented with stage 4 disease (62.2%) and poorly differentiated histology (66.4%). The most common symptoms were abdominal pain and weight loss. On bivariate analysis, advanced stage (P=0.02) and higher grade (P=0.04) were associated with increased mortality. Patients <65 years of age were significantly more likely to have poorly differentiated tumours, while patients ≥65 years had more comorbidities (P=0.001). The 5-year DFS were 35% and 37% for patients <65 years of age and ≥65 years of age, respectively (P=0.15).ConclusionsHigher grade and advanced stage are associated with worse survival in patients with GC, but age did not seem to have an impact. Screening high risk patients and early diagnosis are necessary to improve survival. 相似文献
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4.
《Clinical genitourinary cancer》2020,18(5):e557-e562
BackgroundConsensus guidelines recommend gemcitabine and cisplatin (GC) or dose-dense methotrexate, vinblastine, doxorubicin, and cisplatin (ddMVAC) as equally preferable neoadjuvant chemotherapy before cystectomy for muscle-invasive bladder cancer. This study sought to compare the ability of GC and ddMVAC to achieve pathologic response; and to evaluate the benefit of switching regimens after 1 or 2 cycles of the other.Patients and MethodsPatients aged ≥ 18 with muscle-invasive bladder cancer (≥ cT2) and who had received either GC or ddMVAC as neoadjuvant chemotherapy followed by cystectomy were retrospectively evaluated using the electronic medical record. Patients who received 1 or 2 cycles of one regimen followed by several cycles of the other regimen before cystectomy were classified as switch therapy patients. This study assessed the rates of pathologic complete response (pCR) and any degree of downstaging.ResultsAmong 109 patients who received GC or ddMVAC, 7 (21%) of 33 ddMVAC patients demonstrated pCR, and 19 (25%) of 76 GC patients demonstrated pCR (odds ratio, 1.24; 95% confidence interval, 0.46-3.31; P = .67). Downstaging rates were 39% for ddMVAC and 50% for GC (P = .31). Thirty-three of 36 patients aged ≥ 70 years received GC (P < .001). Four of 7 patients treated with switch therapy showed downstaging, and 2 of 7 experienced pCR.ConclusionThere was no difference in pCR rates between GC and ddMVAC, and patients were most often able to receive 3 or 4 cycles of treatment. Switch therapy may be of benefit in patients whose disease has a poor initial response. 相似文献
5.
一测多评法(quantitative analysis of multi-components by single marker,QAMS)已成熟应用于中药材、中药提取物及中成药领域等中药复杂体系的质量评价研究中,有效解决了因对照品缺乏而导致的多指标质控技术推广难问题。本文查阅近五年的国内外研究文献,重点总结了高效液相色谱、气相色谱和质谱等技术在QAMS法中药质量控制中的应用。高效液相色谱联用紫外检测器(UV)技术应用最为广泛,最适合于中药QAMS法定量,结果稳定、准确;而高效液相色谱联用蒸发光检测器在中药QAMS法应用中,其测定准确性和适用性仍然需进一步探索和验证。液质联用技术虽然具有灵敏度高、线性范围宽等优点,但易受仪器参数、基质效应等的影响。进一步发展HPLC-UV技术在中成药制剂质量评价中的应用,是QAMS法多成分定量值得关注的方向;探索LC-MS和GC技术在中药QAMS质量评价中的稳定性和普适性是未来将面临的挑战。 相似文献
6.
Analytical procedure for detection and quantification of etaqualone in human blood and urine using GC–MS/MS was established and applied to authentic human samples obtained from volunteers. A liquid–liquid extraction method was employed. Each 1.0 mL of blood or urine was alkalized and extracted with diethyl ether. The solvent layer was evaporated to dryness and reconstituted with methanol then analyzed by GC–MS/MS. linear relationships within the concentration range of 1–100 ng/mL were obtained in calibrators for both blood and urine, demonstrating correlation coefficients values being>0.999. For blood and urine samples, the intra-day assay precision and accuracy values are each less than 3.65%, 7.13%, and 6.02%, 9.12%; those values of the inter-day assay are each less than 1.82%, 6.74%, and 3.99%, 7.41%. The extraction recovery rates for etaqualone ranged from 98.7% to 106%. The lower limit of quantifications was 1.0 ng/mL in both blood and urine. Stabilities of etaqualone in blood and urine were satisfactory under various temperatures within 15 days. 8.51 and 2.06 ng/mL of etaqualone in blood and urine were detected at 4 h later oral ingestion; 6.91 and 3.94 ng/mL of etaqualone were also detected 30 min and 2 h later smoking from blood and urine. 相似文献
7.
ObjectiveThe objective of this study was to estimate the antibacterial activity of three different herbal extracts against oral bacteria and their bioactive composition.MethodsUsing the disk diffusion technique, the antibacterial activities of three different extracts (lemongrass, sage, and guava leaf) were evaluated against oral bacteria (Streptococcus mutans, Staphylococcus aureus, and Enterococcus faecalis). Additionally, the bioactive components of the herbal extracts were assessed by employing the gas chromatography-mass spectrometry technique.ResultsThe sage, lemongrass, and guava leaf extracts suppressed the proliferation of all three tested bacterial strains at different rates. The phytochemical analysis revealed that sage extract possessed the highest content of antioxidants, phenols, and flavonoid compounds. The gas chromatography-mass spectrometry analysis of the tested plants revealed the presence of vital bioactive compounds.ConclusionsLemongrass, sage, and guava leaf extracts have potent antibacterial activities, are rich in bioactive compounds, and could be utilized as natural remedies for the prevention of oral diseases. 相似文献
8.
目的 通过体外实验研究酪蛋白磷酸多肽-无定形磷酸钙(cvv-ACP,商品名护牙素)对固定矫治中托槽周围牙釉质脱矿的预防作用.方法 将60颗因正畸治疗而拔除的前磨牙随机分成四组:①护牙素组;②0.2%NaF组;③0.2%NaF 护牙素组;④空白对照组.在牙齿颊面粘结正畸托槽.体外pH循环35天后.每组取10个样本经切片、磨片至厚度100/μm-110μm,采用软X线投照技术及高清晰度数码显微图像分析系统测量釉质脱矿深度和灰度.另外,每组取5个样本用扫描电镜观察釉质表面超微结构的改变.用SPSSl3.0统计软件进行数据处理分析.结果 形态学表现:软X线照片显示护牙素组、0.2%NaF组、0.2%NaF 护牙素组都没有出现明显脱矿,对照组出现了19.34±6.8pJn深的脱矿.扫描电镜显示前三组的牙釉质表面有矿物质沉积,孔隙变小,对照组的牙釉质表面有程度不等蜂窝状孔隙.灰度值比较结果显示:①护牙素组、0.2%NaF组之间脱矿量没有统计学差异(P>O.05);②护牙素组、0.2%NaF组、0.2%NaF 护牙素组的脱矿量与空白对照组之间有显著的统计学差异(P相似文献
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10.
Susanne Unger Maximilian Seidl Pauline van Schouwenburg Mirzokhid Rakhmanov Alla Bulashevska Natalie Frede Bodo Grimbacher Jens Pfeiffer Klaudia Schrenk Luis Munoz Leif Hanitsch Ina Stumpf Fabian Kaiser Oliver Hausmann Florian Kollert Sigune Goldacker Mirjam van der Burg Baerbel Keller Klaus Warnatz 《The Journal of allergy and clinical immunology》2018,141(2):730-740