Impact of Adjuvant Radiotherapy on Survival after Pancreatic Cancer Resection: An Appraisal of Data from the National Cancer Data Base

Purpose

The impact of adjuvant radiotherapy for pancreatic adenocarcinoma (PAC) remains controversial. We examined effects of adjuvant therapy on overall survival (OS) in PAC, using the National Cancer Data Base (NCDB).

Methods

Patients with resected PAC from 1998 to 2002 were queried from the NCDB. Factors associated with receipt of adjuvant chemotherapy (ChemoOnly) versus adjuvant chemoradiotherapy (ChemoRad) versus no adjuvant treatment (NoAdjuvant) were assessed. Cox proportional hazard modeling was used to examine effect of adjuvant therapy type on OS. Propensity scores (PS) were developed for each treatment arm and used to produce matched samples for analysis to minimize selection bias.

Results

From 1998 to 2002, a total of 11,526 patients underwent resection of PAC. Of these, 1,029 (8.9 %) received ChemoOnly, 5,292 (45.9 %) received ChemoRad, and 5,205 (45.2 %) received NoAdjuvant. On univariate analysis, factors associated with improved OS included: younger age, higher income, higher facility volume, lower tumor stage and grade, negative margins and nodes, and absence of adjuvant therapy. On multivariate analysis with matched PS, factors independently associated with improved OS included: younger age, higher income, higher facility volume, later year of diagnosis, smaller tumor size, lower tumor stage, and negative tumor margins and nodes. ChemoRad had the best OS (hazard ratio 0.70, 95 % confidence interval 0.61–0.80) in a PS matched comparison with ChemoOnly (hazard ratio 1.04, 95 % confidence interval 0.93–1.18) and NoAdjuvant (index).

Conclusions

Adjuvant chemotherapy with radiotherapy is associated with improved OS after PAC resection in a large population from the NCDB. On the basis of these analyses, radiotherapy should be a part of adjuvant therapy for PAC.     

Facile synthesis of chitosan membranes for visible-light-driven photocatalytic degradation of tetracycline hydrochloride

Due to the film-forming ability of polymers, a variety of photocatalytic membranes (PMs) based on polymers easily being separated and reused have been constructed for wastewater contaminant treatment. During their construction processes, chitosan (CS) as a bio-polymer with its distinct merits of abundant resources, low-cost and environmental-friendliness, as well as formability and ease of modification, has attracted great attention. However, the role of CS was mostly believed to be just a support or an adsorbent for fixing or dispersing photocatalysts. Whether CS possessed photocatalytic activity or not still remained vague. Herein, in this work, CS membranes (CSM) were facilely prepared for photocatalytic degradation of tetracycline hydrochloride (TC, a model organic pollutant) in aqueous solution, and its photocatalytic performance was investigated and compared with that of CSP (CS powder) and TiO₂-P25 (a commercially used photocatalyst). The results showed that the single-phased CSM exhibited a better visible light photocatalytic activity. After visible light irradiation for 60 minutes, the degradation efficiency of TC can reach above 90% when the CSM was used as a photocatalyst, while with the same irradiation time interval, less TC could be degraded over both CSP and TiO₂-P25. Through radical scavenging and EPR experiments, ˙O₂⁻ and h⁺ were found to be the main active oxygen species generated in the reaction system for TC degradation. After being washed with 2 wt% NaOH solution, the CSM revealed a good recyclability implying its potential for practical applications. This study would provide a certain theoretical and data basis for the future development of CS-based PMs and photocatalysts.

Chitosan membrane exhibited a good visible light photocatalytic activity over tetracycline hydrochloride degradation. The corresponding degradation mechanism was investigated as shown above.     

Hydrogen evolution reaction at the interfaces of two-dimensional lateral heterostructures: a first-principles study

Owing to the synergetic effects of different two-dimensional (2D) materials, 2D heterostructures have recently attracted much attention in the field of catalysis. We present a first-principles study of hydrogen adsorption on the lateral heterostructure of graphene and h-BN, and its potential application in the hydrogen evolution reaction. The density functional theory calculations in this study show that substantial charge transfer occurs at the heterostructure interfaces, which can enhance the H adsorption on the interfacial atoms. Consequently, the adsorption free energy ΔG_H* of the interfaces becomes close to zero, which is optimal for the hydrogen evolution reaction. The results also demonstrate that ΔG_H* decreases monotonically with increase in the p-band center, indicating that s–p hybridization plays a crucial role in determining the adsorption strength. These findings are expected to be broadly applicable to other 2D lateral heterostructures, providing a new strategy for hydrogen production.

Owing to the synergetic effects of different two-dimensional (2D) materials, 2D heterostructures have recently attracted much attention in the field of catalysis.     

5-ASA对炎症性肠病大鼠结肠组织中TGFβ1/smads信号通路的影响

目的:应用2,4,6-三硝基苯磺酸(TNBS)诱导的大鼠结肠炎模型研究TGFβ1/smads信号途径在5-氨基水杨酸(5-ASA)抗炎过程中的作用。方法:80只Sprague-Dawley大鼠随机分为对照组(n=20)、造模组(n=20)、TNBS+5-ASA口服组(n=20)、TNBS+5-ASA灌肠组(n=20),采用疾病活动指数、大体评分和组织学评分评价TNBS诱导结肠炎的严重程度,通过RTPCR和Western blot检测TGFβ1、smad2、smad3、smad4和smad7 mRNA和蛋白的表达量。结果:造模组smad2、smad3、smad4mRNA和蛋白表达量明显下降,而smad7的mRNA和蛋白表达量明显升高。5-ASA口服和灌肠均可以上调smad2、smad3和smad4 mRNA和蛋白表达,下调smad7的mRNA和蛋白表达,且5-ASA灌肠均优于5-ASA口服。结论:5-ASA可能通过调节TGFβ1/smads途径的信号转导来改善肠黏膜炎症。     

胶质瘤干细胞研究进展

随着对肿瘤干细胞（tumor stem cells）理论的深入认识和分离、培养肿瘤干细胞实验技术的不断进步,胶质瘤内肿瘤干细胞的存在已经有较多的证据和研究。这方面的研究不仅有助于深化人们对胶质瘤发生、复发和侵袭机制的认识,更重要的是可能改变以往胶质瘤的治疗策略,影响十分深远。新近,有学者将来自胶质瘤的肿瘤干细胞或具有干细胞特性的胶质瘤细胞称为“胶质瘤干细胞（glioma stem cells,GSC）”,较好地反映了这类细胞的特性。     

脑缺血再灌对小鼠学习记忆的影响及药物防护

在建立及管性学习记忆障碍模型的基础上，观察脑缺血再灌对小鼠学习记忆的影响及服用尼莫地平、７６４－３、醒脑灵对其的防护作用。重复脑缺血再灌可明显的降低动物的学习和记忆能力，并可通过药物改善小鼠学习记忆障碍的程度。     

70岁以上住院老年慢性病病人抑郁和焦虑的调查

随着医学科学技术的飞速发展和人民物质精神生活水平的日益提高，我国人口的平均预期寿命不断增长，现已接近70岁。据统计：目前我国老年病人口（我国以60岁以上为老年病人）总数已近I．3亿，约占总人口数的10．09％，而75岁以上老年病人以每年平均3．62％的速度增长，预测到2025年将上升到20％，2050年将达到顶峰25．5％。老年人是慢性病的主要患病人群。因此，本研究针对70岁以上患慢性病的住院普通老年人和住院离休干部进行调查，采用Brink老年抑郁量表（GDS）、Zung焦虑自评量表（SAS），以了解住院老年人中存在的焦虑、抑郁情况以及分析两组病人的性别、年龄、文化程度、婚姻状况、个人习惯和经济收入情况。现将结果报道如下。[第一段]