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1.

Background

The prognostic value of HIFs in colorectal cancer was evaluated in a large number of studies, but the conclusions were inconclusive. Meanwhile, clinicopathologic differences of HIF-1α and HIF-2α were rarely compared in recent studies.

Methodology

Identical search strategies were used to search relevant literatures in the PubMed and Web of Science databases. The prognostic significances and clinicopathological differences of HIFs in CRC were analyzed.

Principal Findings

A total of 23studies comprising 2984 CRC patients met the inclusion criteria. The results indicated that overexpressed HIFs were significantly associated with increase of mortality risk, including overall survival (OS) (HR 2.06 95%CI 1.55–2.74) and disease free survival (HR 2.84, 95%CI 1.87–4.31). Subgroup analysis revealed that both overexpressed HIF-1α and HIF-2α had correlations with worse prognosis. The pooled HRs were 2.01 (95% CI: 1.55–2.6) and 2.07(95% CI: 1.01–4.26). Further subgroup analysis on HIF-1α was performed by study location, number of patients, quality score and cut-off value. The results showed that HIF-1α overexpression was significantly associated with poor OS, particularly in Asian countries (HR 2.3, 95% CI: 1.74–3.01), while not in European or other countries. In addition, overexpression of HIF-1α was closely related with these clinicopathological features, including Dukes'' stages (OR 0.39, 95% CI: 0.17–0.89), UICC stages (OR 0.42 95% CI: 0.3–0.59), depth of invasion (OR 0.71, 95% CI: 0.51–0.99), lymphnode status (OR 0.49, 95% CI: 0.32–0.73) and metastasis (OR 0.29, 95% CI: 0.11–0.81). While overexpression of HIF-2α was only associated with grade of differentiation (OR 0.48, 95% CI: 0.29–0.81).

Conclusions

This study showed that both HIF-1α and HIF-2α overexpression were associated with an unfavorable prognosis. HIF-1α overexpression seemed to be associated with worse prognosis in Asian countries. Additionally, HIF-1α and HIF-2α indicated distinct clinicopathologic features.  相似文献   
2.

Introduction

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is characterised by the autoinflammation and necrosis of blood vessel walls. The renal involvement is commonly characterised by a pauci-immune crescentic glomerulonephritis (PiCGN) with a very rapid decline in renal function. Cathelicidin LL37, an endogenous antimicrobial peptide, has recently been implicated in the pathogenesis of autoimmune diseases. To assess whether serum LL37 reflects renal crescentic formation, we measured the serum levels of LL37 in AAV patients with and without crescentic glomerulonephritis (crescentic GN) as compared to healthy controls (HCs). We also analysed the correlation of the serum levels of LL37 and interferon-α (IFN-α) with the clinical characteristics of the patients.

Methods

The study population consisted of 85 AAV patients and 51 HCs. In 40 ANCA-positive patients, a parallel analysis was performed, including the assessment of LL37 and IFN-α levels in the serum and renal biopsies. Of those studied, 15 AAV patients had biopsy-proven crescentic GN, and 25 AAV patients lacked crescent formation. The serum levels of cathelicidin LL37 and IFN-α were both measured by ELISA, and the clinical and serological parameters were assessed according to routine procedures. Immunofluorescence staining was performed on frozen sections of kidney needle biopsies from AAV patients with crescentic GN.

Results

The serum levels of LL37 and IFN-α were significantly increased in AAV patients with crescentic GN compared to AAV patients without crescentic formation and HCs, and patients with high LL37 and IFN-α levels were more likely to be in the crescentic GN group. The LL37 levels were positively correlated with the IFN-α levels, and both LL37 and IFN-α levels showed a positive correlation with serum creatinine and no correlation with complement C3. The renal tissue of crescentic GN patients showed expression of LL37 and IFN-α at the Bowman’s capsule and extracellular sites, suggesting the active release of LL37 and IFN-α.

Conclusions

Significantly higher levels of LL-37 and IFN-α were observed in AAV patients, particularly those with crescentic formation, and LL37 and IFN-α were expressed in the renal tissue of patients with crescentic GN. These data suggest that serum levels of LL37 and IFN-α may reflect both local renal inflammation and systemic inflammation.  相似文献   
3.
农业生态旅游研究进展   总被引:1,自引:0,他引:1  
在广泛调研现有农业生态旅游研究成果的基础上,从农业生态旅游的概念、特性、国内外研究现状、研究意义和研究方法方面,对农业生态旅游进行了评述。  相似文献   
4.
Yu  Qilong  Sun  Wenjing  Han  Yingyan  Hao  Jinghong  Qin  Xiaoxiao  Liu  Chaojie  Fan  Shuangxi 《Plant Growth Regulation》2022,96(3):497-509
Plant Growth Regulation - Lettuce is a popular fresh vegetable, and high-temperature stress will reduce the yield of lettuce. Spermidine is an essential phytohormone in plant stress responses....  相似文献   
5.
酸铝胁迫是限制植物正常生长发育的重要非生物胁迫因子,严重制约了我国酸性土壤地区的农业生产水平。植物抵御酸铝胁迫的形式复杂多样,如分泌有机酸、提高根际pH、分泌黏液、细胞壁对Al3+的固定、有机酸对细胞溶质中Al3+的螯合与液泡区隔化等。现有研究多集中于常规生理特征分析,缺乏深入的分子生物学解析。基于此,本文对国内外植物适应酸铝胁迫机理的相关研究进行了归纳和总结,从酸铝胁迫对植物生长与生理代谢的影响、植物适应酸铝胁迫最主要的两种生理机制(Al排除机制、Al耐受机制)以及分子水平上调控相关耐铝基因进行了综述。最后针对现有研究的不足提出了展望,以期为深入揭示植物适应酸铝胁迫的机理以及挖掘适于酸土生长的优质作物资源提供理论依据。  相似文献   
6.

Objectives

The contribution of ultrasound-assisted thoracic paravertebral block to postoperative analgesia remains unclear. We compared the effect of a combination of ultrasound assisted-thoracic paravertebral block and propofol general anesthesia with opioid and sevoflurane general anesthesia on volatile anesthetic, propofol and opioid consumption, and postoperative pain in patients having breast cancer surgery.

Methods

Patients undergoing breast cancer surgery were randomly assigned to ultrasound-assisted paravertebral block with propofol general anesthesia (PPA group, n = 121) or fentanyl with sevoflurane general anesthesia (GA group, n = 126). Volatile anesthetic, propofol and opioid consumption, and postoperative pain intensity were compared between the groups using noninferiority and superiority tests.

Results

Patients in the PPA group required less sevoflurane than those in the GA group (median [interquartile range] of 0 [0, 0] vs. 0.4 [0.3, 0.6] minimum alveolar concentration [MAC]-hours), less intraoperative fentanyl requirements (100 [50, 100] vs. 250 [200, 300]μg,), less intense postoperative pain (median visual analog scale score 2 [1, 3.5] vs. 3 [2, 4.5]), but more propofol (median 529 [424, 672] vs. 100 [100, 130] mg). Noninferiority was detected for all four outcomes; one-tailed superiority tests for each outcome were highly significant at P<0.001 in the expected directions.

Conclusions

The combination of propofol anesthesia with ultrasound-assisted paravertebral block reduces intraoperative volatile anesthetic and opioid requirements, and results in less post operative pain in patients undergoing breast cancer surgery.

Trial Registration

ClinicalTrial.gov NCT00418457  相似文献   
7.
采用低温恒温槽处理离体叶片后测定其电解质外渗率,并结合Logistic方程得出低温半致死温度的方法,评价农业部景洪橡胶树种质资源圃中的30个橡胶树品种的抗寒性。结果表明,品种‘RRIM712’、‘云研80-1983’、‘云研77-4’、‘PR107’、‘RRIM524’抗寒性强,低温半致死温度在-4~0℃之间;品种‘云研76-398’、‘RRIM523’抗寒性弱,低温半致死温度在4~7℃之间;其他品种抗寒性居中。橡胶树在低温胁迫下,超氧阴离子的产生速率与橡胶树的抗寒性无直接关系,但不同温度下的变化幅度越小,抗寒性越高;SOD活性随温度降低迅速提高,CAT随温度降低表现出活性降低的趋势。  相似文献   
8.
Eimeria acervulina 3-1E antigen gene and mature chicken interleukin 15 (mChIL-15) gene were cloned into expression vector pcDNA3.1(+) in different forms, produced DNA vaccine pcDNA3.1-3-1E, and pcDNA3.1-3-1E-linker-mChIL-15 co-expressing E. acervulina 3-1E gene and mChIL-15 gene, respectively. The expression of objective gene in vitro was detected by indirect fluorescent antibody technique and immunohistochemistry. The two DNA vaccines were administered by intramuscular leg injection. An animal challenge experiment was carried out to evaluate the immune protective efficacy of the vaccines. The results indicated that DNA vaccines were successfully constructed and the expression of objective gene could be detected in vitro. The animal experimental results showed that both DNA vaccines could provide partial protection against homologous challenge in chickens. The chimeric DNA vaccine, pcDNA3.1-3-1E-linker-mChIL-15, could significantly increase oocyst decrease ratio, reduce the average lesion score in the duodenum, improve body weight gain, and increase anti-coccidial index (ACI) compared to the DNA vaccine pcDNA3.1-3-1E. Taken together, these results demonstrate ChIL-15 enhance the immunogenicity of 3-1E DNA vaccine, and co-expression of cytokine and optimized surface antigen of Eimeria may be a promising method to enhance immunogenicity of DNA vaccines in poultry.  相似文献   
9.
双胶润通胶囊润肠通便功能的研究   总被引:1,自引:0,他引:1  
目的:探讨双胶润通胶囊的润肠通便作用的效果及剂量.方法:实验采用动物试验,将小白鼠(雌雄各半,体重18~22 g)分成两个实验组,每组50只,实验一组进行小肠推进试验,实验二组进行排便试验,时间均为7 d.按推荐剂量每人每日5 g设计,分为低、中、高3个剂量组,另设空白对照和模型对照组.结果:在不影响小鼠体重的情况下,双胶润通胶囊高剂量组小肠推进率与模型对照组比较差异均有显著性变化(P《0.05);3个剂量组小鼠的首便时间、粪便粒数均高于便秘模型对照组,差异具有极显著性差异(P《0.01);结论:双胶润通胶囊对小鼠小肠运动有增强作用,并能缩短小鼠首便时间、增加小鼠的粪便粒数与重量,即:具有润肠通便作用.  相似文献   
10.
为了探讨绿化植物生活型构成对边坡植被物种多样性及护坡性能的影响, 揭示生活型构成-群落特征-物种多样性-生态系统功能间的内在联系, 借助三物种组装实验, 分别构建以草本、灌木或乔木为主体的草本型(HHXi)、灌木型(SSXi)、乔木型(AAXi)或草-灌-乔混合型(HSA)配置模式的实验小区, 对实验区内边坡植被的群落特征、护坡性能进行持续4年的生态监测。结果表明: (1)边坡植被的物种丰富度与绿化植物生活型构成有关, AAXi的物种丰富度总体高于其他模式, 呈AAXi > SSXi > HSA > HHXi趋势。(2)不同配置模式边坡植被的群落盖度不一样, 年际间差异显著: 建坪初期(2010-2011年), HHXi的群落盖度远高于其他模式, HSA次之, AAXi最低; 2012-2013年间, HSA的群落盖度最高, HHXi次之, AAXi最低。(3)边坡植被的Shannon-Wiener指数、Pielou指数与绿化植物生活型构成有关, 其变化规律与群落盖度类似: 建坪初期, HHXi的多样性水平远高于其他模式, 呈HHXi > HSA > SSXi > AAXi趋势; 之后, 呈HSA > HHXi > SSXi > AAXi趋势。(4)边坡植被的护坡性能与群落内的物种多样性密切相关: 多样性水平越高, 护坡性能越强。可见, 在生态护坡过程中, 绿化植物生活型构成对提高边坡植被物种多样性、改善护坡性能至关重要。  相似文献   
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