鼻咽癌放疗后复发的分子机理研究进展

鼻咽癌（nasopharyngeal carcinoma,NPC）放疗后复发是导致治疗失败的主要原因。放射治疗诱发的瘤细胞DNA损伤修复能力及细胞凋亡调控的不同直接影响瘤细胞对放疗的敏感性。近几年提出的肿瘤干细胞（TSC）理论认为,肿瘤复发、转移以及对治疗的耐受等均与TSC相关。本文将从放疗所致的DNA损伤修复,瘤细胞凋亡和肿瘤干细胞三个方面来对NPC鼻咽癌放疗后复发机制作一综述。     

血管生成素样蛋白在肿瘤发生发展中的作用

血管生成素样蛋白（ANGPTLs）是一类与血管生成素结构相似的分泌型糖蛋白,其在实体肿瘤的侵袭转移、血管生成、细胞凋亡等过程中发挥重要的调节作用。局部乏氧是肿瘤微环境最突出的特征,其介导多个生物学过程,进而影响肿瘤的进展以及治疗效果。ANGPTLs家族中的部分蛋白可作为乏氧诱导因子1的下游靶基因,调节肿瘤的生理功能。因此,阐明ANGPTLs在肿瘤中的作用及其机制对提高肿瘤治愈率和改善患者预后具有重要意义。笔者概述了ANGPTLs家族的生物学特征、在肿瘤发生发展以及肿瘤乏氧微环境中可能的作用。     

肿瘤转移的微环境及其临床意义

肿瘤转移的概念和机制研究在不断深化,肿瘤的发生、成长及转移与其微环境密切相关。本文对肿瘤转移的概念、微环境中蛋白酶基质金属蛋白酶家族、半胱氨酸组织蛋白酶等与转移的关系进行阐述。提出对肿瘤细胞与微环境作用的信号传导和分子机制的研究将为肿瘤的诊断和治疗提供新途径。     

HMGB1在肝脏炎症微环境及肝细胞癌发生发展中的作用

高迁移率族蛋白B1(HMGB1)是一种具有多种功能的核相关蛋白,在肝脏肿瘤的发生发展中作用巨大,尤其是在其中的一个重要环节即炎症微环境中发挥着重要作用。在肝细胞癌中,HMGB1作为一种重要的炎症介质通过一系列信号通路促进肿瘤进展,同时在肿瘤自身的炎症微环境中,HMGB1也通过相关信号分子促进炎症微环境本身的发生,并进一步引起肝细胞癌的发生发展。HMGB1在炎症微环境中促进肿瘤发生发展的机制是肿瘤诊断、治疗研究中的热点。本文就目前HMGB1在肝脏炎症微环境中的作用及其在肝细胞癌发生、发展及治疗中的作用作一综述。     

放疗促进肿瘤转移的研究进展

肿瘤细胞从原发病灶迁移到远处部位形成转移病灶的过程增加了患者的病死率。放疗可通过电离直接或通过产生活性氧间接导致DNA损伤，从而杀死肿瘤细胞。然而，近年来的研究结果表明，放疗诱导的肿瘤微环境变化在某些情况下可促进肿瘤转移而导致治疗失败。放疗后肿瘤微环境变化与肿瘤转移的关系受到广泛关注，但其机制尚不明确。笔者对放疗如何通过诱导细胞因子表达、缺氧、整合素表达水平升高以及外泌体变化等因素从而促进肿瘤的转移进行综述。     

肿瘤微环境中过表达的IL-6对大鼠间充质干细胞恶性转化的影响

目的 分析肿瘤微环境中异常高表达的白介素6(IL-6)是否可导致间充质干细胞(MSCs)的恶性转化.方法 ELISA法检测肿瘤微环境与正常微环境中IL-6的表达差异.以肿瘤微环境中相应水平IL-6处理的MSCs为实验组,正常微环境中相应水平IL-6处理的MSCs作为正常对照组.采用免疫荧光法检测各组STAT3蛋白表达情况;通过细胞生长曲线观察各组MSCs增殖能力的变化;采用免疫荧光定量PCR和Western blotting检测p53和MDM2的蛋白及mRNA表达变化;通过裸鼠成瘤实验检测各组MSCs的体内成瘤能力.结果 肿瘤微环境中IL-6的表达量为191.23±16.80pg/ml,明显高于正常微环境(0.82±0.12g/ml,P＜0.01).实验组90％±7％的MSCs表达STAT3蛋白,主要集中于细胞核,为激活状态,而对照组未检测到STAT3表达.细胞生长曲线显示,2个月后实验组MSCs生长接触抑制减弱.细胞培养2个月后,与对照组比较,实验组p53蛋白及mRNA表达明显降低(P＜0.01),MDM2蛋白及mRNA表达明显升高(P＜0.05).实验组MSCs培养2个月后,接种裸鼠皮下可形成肿瘤,而对照组接种后未见肿瘤形成.结论 肿瘤微环境中过表达的IL-6具有促进MSCs恶性转化的作用.     

乏氧微环境下外泌体对肿瘤进展及辐射抵抗的影响

肿瘤的发生发展是一个复杂的生物学过程,涉及诸多的因素。乏氧是实体肿瘤微环境的显著特征之一,乏氧微环境可导致肿瘤的适应性更强、恶性程度更高并产生耐药性。研究发现,外泌体是介导肿瘤生物学过程的重要因子,而乏氧环境下产生的外泌体在某些生物学过程中的作用更为显著。因而,研究乏氧环境下外泌体对了解肿瘤的发展进程,控制肿瘤的生长具有重要意义。笔者简单概述了外泌体在肿瘤乏氧微环境中的作用,以期为肿瘤生物学的研究提供一定的理论基础。     

肿瘤微环境响应性MRI纳米探针研究进展

肿瘤微环境与肿瘤的增殖、血管生成、侵袭、迁移和耐药性等密切相关,因此检测肿瘤微环境有助于深入了解肿瘤发展进程,利于临床评估并改善治疗方案.将MRI与纳米探针相结合,有望无创地获取实时、高分辨率、细胞水平乃至分子水平的肿瘤病理信息.本文综述了近年来基于肿瘤微环境特征设计的响应性MRI纳米探针的研究进展.     

MR扩散加权成像和分子成像在卵巢肿瘤微环境中的应用研究进展

卵巢癌是女性生殖系统的常见恶性肿瘤之一,其早期发现困难,确诊时多为中晚期,常有腹膜转移,手术难以完全切除,复发率高。这与由肿瘤细胞、肿瘤基质成分、炎性细胞和间质细胞构筑的肿瘤微环境中启动肿瘤细胞生长、开启肿瘤血管生成、促进肿瘤细胞迁徙和浸润、肿瘤细胞免疫逃逸等决定病人预后的一系列发生机制不明有很大关系。采用结构成像、功能成像和分子成像相结合的医学成像方法,进行实时动态、多元精准和在体无创研究及评估卵巢癌微环境,对监测卵巢癌的生物学行为和疗效以及预后判断具有重要意义。     

肿瘤干细胞在肿瘤转移相关机制中研究进展

<正>肿瘤干细胞(cancer stem cells,CSCs)是指肿瘤组织中一类被干细胞化、具有明显干细胞特征性的细胞。其能在自我更新复制、潜在分化能力及维持肿瘤细胞稳态等功能的作用下促进肿瘤生长,是导致肿瘤发生、诱导肿瘤转移的关键因素。CSCs参与肿瘤转移过程的分子机制包括肿瘤微环境、上皮-间     

Physiologic and pathologic calcifications and ossifications in the face and neck

The aim was to give a systematic presentation of physiologic and pathologic calcifications and ossifications in the face and neck with a special emphasis on clinical relevance. In a sometimes subacute setting one should recognize specific calcifications which often lead to important diagnoses such as fungal sinusitis or sclerosing labyrinthitis. In a more chronic situation intraocular calcifications in small children are pathognomonic for retinoblastoma. Juxtatumoral sclerosis of the laryngeal cartilage in laryngopharyngeal carcinoma is usually caused by tumor infiltration of the cartilage resulting in a higher tumor stage and, this way, has a major impact on the therapeutical strategy. Calcified lymph nodes are mainly unspecific but can be the result of tuberculosis or metastases of thyroid cancer. Cross-sectional imaging methods, most of all computed tomography, are ideally suited to reveal head and neck calcifications and ossifications, especially those which are clinically relevant.     

Head and neck infection and inflammation

This article discusses the imaging manifestations of infectious and inflammatory conditions of the head and neck. Special attention is paid to the sites, routes of spread, and complications of neck infections. Because the clinical signs and symptoms and the complications of these conditions are often determined by the precise anatomic site involved, anatomic considerations are stressed. Familiarity with the fascial layers, spaces of the neck, and the contents of each space is helpful for this discussion. The fascial layers of the neck are important barriers to infection, and once infection is established, the fascial layers play a part in directing its spread.     

幽门螺杆菌分泌与重组表达的VacA蛋白的分离纯化及其致细胞空泡效应与凋亡的对比研究

目的：分离纯化幽门螺杆菌分泌和重组表达的细胞空泡毒素抗原（ VacA）蛋白,并评价其致细胞空泡效应及致细胞凋亡效应。方法分别从幽门螺杆菌ATCC26695菌株培养上清和重组表达VacA蛋白的pQE30-VacA-E．coliM15基因工程菌中分离纯化VacA蛋白,经酸化后,以不同终浓度（5,10 ng／ml）分别与人胃腺癌AGS细胞共孵24 h,观察致空泡效应,并通过流式细胞术检测细胞凋亡。结果成功分离纯化出幽门螺杆菌分泌和重组表达的VacA蛋白;幽门螺杆菌分泌的VacA蛋白能显著引起AGS细胞的空泡样改变及凋亡（P＜0．01）,而重组表达的VacA蛋白致细胞空泡样改变及凋亡不显著（ P＞0．05）。结论幽门螺杆菌分泌的VacA蛋白有良好的空泡毒性及致凋亡效应,而重组表达的VacA蛋白无致空泡及凋亡效应,幽门螺杆菌分泌的VacA蛋白可用于VacA作用机制的研究。     

化学和生物学融合对国际武器公约履约的影响

化学武器公约（ CWC）和生物武器公约（ BWC）是为禁止生产、发展、储存和使用化学武器和生物武器而制定的国际公约。近年来,科学技术快速发展,知识交叉渗透,学科之间出现整合和融合,促进了科技进步和经济发展。其中化学和生物学融合在有力促进制药、健康卫生、绿色化学和环境保护等产业进步的同时,也对化学和生物武器公约的履约产生了重要的影响。该文综述了与化学武器和生物武器公约相关的化学和生物学融合进展,并分析其对公约履约的影响。     

Oxygen uptake and ventilation during rowing and running in females and males

This study evaluated if the ventilatory response to exercise is impaired by the cramp position of rowing. Maximal oxygen uptake (VO2max), maximal expiratory volume (VEmax), and maximal heart rate (HRmax) during rowing and running were compared in 55 males (age, mean +/- SD, 21 +/- 3 years; height 176 +/- 5 cm; body mass 72 +/- 6 kg) and 18 females (age 20 +/- 2 years; height 164 +/- 5 cm; body mass 61 +/- 4 kg). VEmax was larger during rowing than during running (males, 157 +/- 16 vs. 147 +/- 13 L min(-1); 114 +/- 9 vs. 105 +/- 11 L min(-1), P<0.01). Also VO2max was larger during rowing than during running (males, 4.5 +/- 0.5 vs. 4.3 +/- 0.4 L min(-1); females, 3.3 +/- 0.4 vs. 3.2 +/- 0.4 L min(-1), P<0.01). However, HRmax was lower during rowing than during running (males, 194 +/- 8 vs. 198 +/- 11 beats min(-1); females, 192 +/- 6 vs. 196 +/- 8 beats min(-1), P<0.05). VEmax was correlated to body mass and fat-free mass, as was VO2max. Thus, the oxygen pulse (VO2max/HRmax) was larger during rowing than during running, while the ventilatory equivalent for oxygen (VEmax/VO2max) was similar. We showed that bending the body during rowing does not seem to impair ventilation either in males or in females. The results indicate that VEmax and VO2max relate to body size and fat-free mass for both females and males. The findings indicate that the involvement of more muscles, the entrainment, and the body position during rowing facilitates ventilation and venous return and lowers maximal heart rate.     

Old and dangerous: Prison and dementia

Older prisoners are the fastest growing group of prisoners in many countries. The purpose of this study is to explore the phenomenon of detention of persons suffering from dementia. Medline searches were conducted for relevant articles, chapters and books published until August 2016. Search terms included dementia, elderly, prison and criminal. Publications found through this indexed search were reviewed for further relevant references. As results, there is a lack of data about elderly with dementia in prisons. Given the rise in the average age, it is reasonable to hypothesize that the number of older prisoners is growing. Moreover, some elderly are imprisoned with a concomitant cognitive impairment or psychiatric disorder while others will develop such diseases once incarcerated. At the present time, legal and social systems seem unprepared to handle the phenomenon of dementia in prison. As proposal, health assessments for older first time offenders should become a practice inside the correctional facilities and include an evaluation for specific health issues, such as psychiatric comorbidity and cognitive impairment.     

Kidney and iodinated and gadolinium-based contrast agents

In patients with renal failure, iodinated contrast agents may cause acute deterioration of the renal function and gadolinium-based contrast agents (GBCAs) may cause nephrogenic systemic fibrosis (NSF). The administration of a contrast agent must thus be reviewed for each patient and evaluation of renal function is paramount even though its estimation using formulas derived from the creatinine level may fluctuate. For iodinated contrast agents, contrast induced nephropathy is reduced by hydratation, preferably intravenous, when the GFR is less than 60 ml/min. The risk for intravenous injections is less than the risk for arterial injections, and the GFR threshold may be reduced to 45 ml/min. For gadolinium-based contrast agents, patients at risk for NSF are those with end-stage renal disease and patients undergoing dialysis. In such cases, the injection of a gadolinium-based contrast agent is only considered after a risk-benefit analysis has been completed, an alternate linear or macrocyclic agent issued and the dose limited to 0,1 mmol Gd/kg. Recently, recommendations from US and European agencies have converged. Learning objectives: to be familiar with the risk factors of CIN with iodinated contrast agents; to be familiar with hydration procedures for patients at risk of CIN; to be familiar with the diagnostic criteria of NSF; to be familiar with the classification of GBCA with regards to the risk of NSF; to be familiar with the contraindications of the different groups of GBCA.     

Coracoclavicular and coracoacromial ligament calcification and ossification

Thirty-six patients with calcification or ossification at or around the coracoclavicular and coracoacromial regions were analyzed with regard to type, location, and configuration of the deposits and related clinical history. Calcification or ossification in the coracoclavicular region resulted largely from trauma (36%) or renal failure (28%). Trauma patients may develop punctate calcification or ossification but do not develop the tumoral type of calcification. About 5% of the renal failure patients had coracoclavicular ligament calcifications, one-half of which were of the tumoral type. Renal failure patients may have punctate or tumoral calcifications but do not develop ossification.