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1.
地鳖中的纤溶活性蛋白是从地鳖中提取的具有抗栓及抗肿瘤作用的有效成分,其口服易被上消化道酶分解从而限制了应用。采用恒流泵滴制法开发地鳖纤溶活性蛋白时间/pH依赖口服结肠靶向微囊(EnpolypHaga fibrinolytic protein oral colon targeting microcapsules, CTM-EFP)。采用单因素实验和正交实验相结合的方法寻找到包封率为60.17 % ± 2.72 %、载药量为15.50 % ± 0.44 % 的最佳配方。扫描电子显微镜(SEM)显示微囊呈球形、表面光滑,在人工肠液中24 h的累积释放度为99.53 % ± 0.69 %,在人工胃液中24 h累积释放度为7.43 ± 1.04 %,通过时间/pH依赖达到结肠靶向作用。CTM-EFP在人工肠液中的体外释放曲线符合Korsmeyer方程,提示地鳖纤溶活性蛋白(EnpolypHaga fibrinolytic protein, EFP)是通过扩散和侵蚀机制结合释放的。CTM-EFP为EFP的口服给药提供了一种新的剂型,为EFP应用于临床提供参考。  相似文献   
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PurposeTo examine the annual hospital volume of surgery in relation to survival in colorectal cancer. Previous studies on hospital volume and survival following colorectal cancer surgery are conflicting.MethodsAll 49 032 patients who underwent resection for colorectal cancer in 1987–2016 in Finland were included, with complete follow-up until December 31, 2019. Primary outcome was 5-year mortality. Cox regression provided hazard ratios (HR) with 95% confidence intervals (CI) for quartiles of annual hospital volume for colorectal surgery, adjusted for calendar period, age, sex, comorbidity, stage, tumor location and oncological therapy. Additionally, colon and rectal cancer surgery were assessed separately. Sensitivity analysis of patients with confirmed curative intent was conducted.ResultsCompared to highest quartile (≥108 resections annually), lowest hospital volume (≤37 resections annually) was associated with slightly increased 5-year all-cause mortality (adjusted HR 1.07, 95% CI 1.02–1.12). A pre-planned subgroup-analysis suggested a slightly improved 5-year survival in high-volume institutions for rectal cancer, but not colon cancer surgery. Sensitivity analysis including only those operated with confirmed curative intent suggested no differences between hospital volume groups in colorectal, colon or rectal cancer for 5-year all-cause mortality.ConclusionHigher hospital volume is associated with slightly improved all-cause 5-year mortality in colorectal cancer surgery, but this effect may be limited to rectal cancer surgery only. Volume-outcome relationship in rectal cancer surgery should be investigated further using large datasets. These results do not support centralization of colon cancer surgery based on hospital volume only.  相似文献   
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Objective: Eleutherine palmifolia (L.) Merr. extract (EPE) containing isoliquiritigenin and oxyresveratrol is believed to be an anticancer agent. This study evaluates colon histopathology, TNF-α, TGF-β, and hepatotoxicity on BALB/c mice colitis-associated colon cancer (CAC) model treated with EPE. Methods: In vivo study was performed on BALB/c mice CAC model induced by 10 mg/kgBW AOM on the first day followed by administration that each cycle consisted of 5% DSS in water for seven days and regular water for seven days. The indicators of the formation of CAC were observed by a fecal occult blood test (FOBT) and serum amyloid α (SAA) test. The treatment was conducted once a week started from the seventh week up to the twentieth week with six treatment groups: I was administrated by regular water only (negative control), II was administrated by AOM and DSS only (positive control), III was administrated by doxorubicin,  IV-VI were treated by EPE (0.25 mg/kg BW, 0.50 mg/kg BW, and 1.00 mg/kg BW) respectively. The colon and liver’s histopathology was observed using hematoxylin-eosin (HE) staining, TNF-α with immunohistochemistry (IHC), and level measurement of TGF-β colon with ELISA reader. The data were used one-way ANOVA followed by post hoc as statistical analysis. Results: The administration of EPE increased the expression of TNF-α, the total of goblet cells of the colon, and decreased the level of TGF-β. Administration of EPE 0.50 mg/20g BW decreased a liver histopathological score but induced a histopathological alteration of the liver at a dose of 1.00 mg/20g BW. Conclusion: This study indicate that EPE could be recommended as a colon anticancer through increase the goblet cells, induce apoptosis through increase TNF-α, and decrease TGF-β.  相似文献   
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背景与目的:Musashi1(Msi1)属于RNA结合蛋白家族中的一员,是RNA转录后表达的关键调控者,其是否参与肿瘤的发生、发展,以及具体分子机制仍不十分清楚。探讨沉默Msi1基因对结肠癌HCT116细胞恶性生物学行为的影响及可能的机制。方法:采用慢病毒载体构建稳定低表达Msi1的细胞株,细胞计数试剂盒(cell counting kit-8,CCK-8)实验检测细胞增殖能力,克隆形成实验检测细胞克隆形成能力,流式细胞术(flow cytometry,FCM)检测细胞周期的变化,裸鼠移植瘤模型观察沉默Msi1对裸鼠成瘤的影响。实时荧光定量聚合酶链反应(real-time fluorescence quantitative polymerase chain reaction,RTFQ-PCR)和蛋白质印记法(Western blot)检测沉默Msi1基因后p27基因的mRNA表达和蛋白水平,双荧光素酶实验验证Msi1基因与目的基因p27 3’-非编码区(3’-untranslated region,3’-UTR)的相互作用。结果:沉默Msi1基因后,HCT116细胞的增殖能力显著下降,克隆集落数明显减少,G 0 /G 1 期细胞增多,S期细胞明显减少,裸鼠移植瘤生长明显受到抑制。沉默Msi1基因后p27 mRNA表达未见明显变化,而p27蛋白水平明显上调,双荧光素酶实验证实Msi1基因能与p27 3’-UTR区域直接结合,抑制其翻译。结论:沉默Msi1基因通过靶向上调p27,导致结肠癌HCT116细胞G 0 /G 1 期阻滞,从而抑制肿瘤细胞体内及体外增殖能力。  相似文献   
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背景与目的:化疗是结肠癌的重要治疗方法之一,其方案常含有铂类药物,而化疗耐药会影响结肠癌疗效和预后,其发生机制与基因异常表达有关。高尔基磷酸化蛋白3(Golgi phosphoprotein 3,GOLPH3)是一个癌基因,在结肠癌组织中存在过表达,可促进结肠癌细胞的增殖,与预后不良相关。目前,GOLPH3基因的高表达与结肠癌对铂类耐药的相关性尚不明确。探讨沉默GOLPH3基因逆转人结肠癌HT29细胞对顺铂的化疗耐药效应和机制。方法:HT29细胞分为5组。① 对照组:人结肠癌HT29细胞;② 转染组:siRNA-GOLPH3转染HT29细胞;③ 实验组1:经顺铂处理的HT29细胞;④ 实验组2:经顺铂处理的siRNA-GOLPH3转染HT29细胞;⑤ 实验组3:经顺铂和细胞外调节蛋白激酶(extracellular signal-regulated protein kinases,ERK)1/2抑制剂PD98059处理的HT29细胞。四甲基偶氮唑蓝(methyl thiazolyl tetrazolium,MTT)法、平板克隆形成实验检测各组结肠癌HT29细胞增殖及克隆形成能力。蛋白质印迹法(Western blot)检测GOLPH3、P-糖蛋白(P-glycoprotein,P-gp)、ERK1/2和pERK1/2蛋白的表达。结果:经顺铂处理后,实验组1、实验组2的细胞在波长490 nm处的吸光度(D)值均显著低于对照组(P<0.05),实验组2的D490值显著低于实验组1(P<0.001);实验组1和实验组2的细胞集落数均显著低于对照组(P<0.01),实验组2的细胞集落数显著低于实验组1(P<0.001)。实验组1的P-gp、GOLPH3、pERK1/2蛋白表达量显著高于实验组2(P<0.01);实验组3的P-gp蛋白表达量较实验组1显著降低(P<0.01)。结论:沉默GOLPH3基因可通过抑制丝裂原活化蛋白激酶/细胞外信号调节激酶(mitogen-activated protein kinase/extracellular signal-regulated kinase,MAPK/ERK)信号通路逆转HT29结肠癌细胞对顺铂化疗的耐药性。  相似文献   
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IntroductionDebate persists on the ideal extent of lymphadenectomy for colon cancer (CC). Specifically, it is unknown whether the anatomical location of positive lymph nodes (LN) has any independent prognostic significance. We assessed the prognostic value of positive LN location in stage III CC patients who underwent extensive (D3) lymphadenectomy.MethodsPatients from Kanagawa Cancer Center, Japan, who underwent D3 dissection for CC from 2000 to 16 were analyzed. Mesenteric LN were classified according to location as paracolic (L1), intermediate (L2), or central (L3). Recurrence-free survival (RFS) and the corresponding hazard function were evaluated with their trends over the L groups. Multivariate Cox models were used to evaluate the association of LN location with RFS.ResultsFour hundred forty-six stage III patients were analyzed. The mean number of examined/positive nodes per patient was 42.5/2.6 in L1 (n = 310), 40.9/4.8 in L2 (n = 111), and 44.0/9.8 in L3 (n = 25). RFS was worse for L3 vs. L2 (HR: 2.00, 95%CI [1.05–3.75], p = 0.034) and for L3 vs. L1 (2.62 [1.45–4.71], p = 0.001), but not significantly different between L2 and L1 (1.32 [0.89–1.5], p = 0.17). In a multivariate model adjusting for age, tumor size, and number of lymph nodes harvested T-stage (p < 0.001), adjuvant therapy (p < 0.0038), lymphatic invasion (p = 0.023), and LNR (p = 0.038) were significantly associated with RFS, but not L level or tumor location.ConclusionThe anatomical location of invaded LN does not significantly correlate with RFS in CC, after adjusting for potential confounders. Central LN are infrequently invaded and confer a worse RFS.  相似文献   
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Background: KRAS, NRAS, and BRAF gene mutations are the most clinically relevant and frequently reported incolorectal cancer (CRC). Although data on these genes are frequently reported in several counties, data specific to thesegenes among Thai population are scarce. The aim of this study was to investigate and identify molecular alterationsassociated with colon cancer in Thai population, and to determine the impact of these genetic aberrations on clinicaloutcome. Methods: DNA from 108 archived formalin-fixed, paraffin-embedded (FFPE) tissue samples that histologicallyconfirmed adenocarcinoma of stage II-III colon cancer between 2010 and 2012 at Siriraj Hospital (Bangkok, Thailand)were extracted. Gene mutational analysis was performed by next-generation sequencing (NGS) using an OncomineSolid Tumor DNA kit (Thermo Fisher Scientific, Inc., Waltham, MA, USA). Results: A total of 22 somatic genemutations were detected. The mutation frequency observed in KRAS, NRAS, BRAF, PIK3CA, and FBXW7 mutationswas 47.2%, 1.9%, 1.9%, 12%, and 14.8%, respectively. KRAS mutation codon 12, 13, 59, 61, 117, and 146 mutationswere identified in 29.6%, 8.3%, 1.8%, 0.9%, 0.0%, and 8.3%, respectively. KRAS Exon 4 had better DFS comparedwith Exon 2 and 3. Conclusions: This study is the first to comprehensively report hotspot mutations using NGS in Thaicolon cancer patients. The most commonly identified gene mutation frequencies among Thai patients (KRAS, NRAS,BRAF, TP53, and PIK3CA) were similar to the gene mutation frequencies reported in Western population, except forsubgroup of KRAS codon 146 and FBXW7 mutations that had a slightly higher frequency.  相似文献   
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