Breast cancer stem cells: Multiple capacities in tumor metastasis

Breast cancer is the leading cause of cancer death among women worldwide. Accumulating evidence indicates that the local recurrent and/or distant metastatic tumors, the major causes of lethality in the clinic, are related to the aggressive phenotype of a small fraction of cancer cells loosely termed as cancer stem cells (CSCs), tumor initiating cells (TICs), or cancer metastasis-initiating cells (CMICs). Breast cancer stem cells (BCSCs) are shown to exhibit unique growth abilities including self-renewal, differentiation potential, and resistance to most anti-cancer agents including chemo- and/or radiotherapy, all of which are believed to contribute to the development and overall aggressiveness of the recurrent or metastatic lesions. It is in the urgent need not only to further define the nature of heterogeneity in each tumor but also to characterize the precise mechanisms governing tumor–host cross-talk which is assumed to be initiated by BCSCs. In this review, we will focus on recently identified key factors, including the BCSCs among circulating tumor cells, interaction of BCSCs with the host, epithelial mesenchymal transition (EMT), tumor microenvironment, the intrinsic resistance due to HER2 expression, potential biomarkers of BCSCs and cancer cell immune signaling. We believe that new evidence coming from both bench and clinical research will help to develop more effective approaches to control or significantly reduce the aggressiveness of metastatic tumors.     

放疗诱导宫颈癌细胞中经典Wnt通路的表达情况及顺铂耐药性研究

目的:研究放疗诱导后的耐放疗宫颈癌Hela、Siha细胞系顺铂耐药情况及经典Wnt通路相关分子在其化疗耐受中的作用。方法:分割剂量多次照射诱导宫颈癌细胞并成功建立耐放疗细胞系,将细胞分为R0组(空白对照)、R1组(分割剂量4GY,照射6次)和R2组(分割剂量6GY,照射4次)。CCK8法进行耐药实验,Real-time PCR及Western blot法检测Wnt/β-catenin通路及耐药分子表达情况。结果:Hela R0、R1、R2顺铂IC50分别为3.86、6.65μmol/L和6.53μmol/L,Siha R0、Siha R1、Siha R2顺铂IC50分别为4.79、7.25μmol/L和7.98μmol/L;与R0组相比,其他两组的IC50显著升高,差异有统计学意义(P0.001)。放疗诱导宫颈癌Hela、Siha细胞中经典Wnt通路分子在基因与蛋白水平受到激活,其下游基因C-Myc、Cyclin D1表达增多,放疗诱导Hela细胞中耐药蛋白ABCB1、ABCG2表达升高,而放疗诱导Siha细胞中上述耐药蛋白变化无统计学差异。结论:经典Wnt通路可能是放疗诱导宫颈癌细胞化疗耐受性获得的重要机制,这为复发性宫颈癌患者提供了潜在治疗靶点。     

Improvement to the Corrosion Resistance of Ti-Based Implants Using Hydrothermally Synthesized Nanostructured Anatase Coatings

The electrochemical behavior of polycrystalline TiO₂ anatase coatings prepared by a one-step hydrothermal synthesis on commercially pure (CP) Ti grade 2 and a Ti13Nb13Zr alloy for bone implants was investigated in Hank’s solution at 37.5 °C. The aim was to verify to what extent the in-situ-grown anatase improved the behavior of the substrate in comparison to the bare substrates. Tafel-plot extrapolations from the potentiodynamic curves revealed a substantial improvement in the corrosion potentials for the anatase coatings. Moreover, the coatings grown on titanium also exhibited lower corrosion-current densities, indicating a longer survival of the implant. The results were explained by considering the effects of crystal morphology, coating thickness and porosity. Evidence for the existing porosity was obtained from corrosion and nano-indentation tests. The overall results indicated that the hydrothermally prepared anatase coatings, with the appropriate morphology and surface properties, have attractive prospects for use in medical devices, since better corrosion protection of the implant can be expected.     

Drug Use and Drug Policy in Hong Kong: Changing Patterns and New Challenges

This paper is a sociohistorical examination of drug misuse and drug policy in Hong Kong. It briefly traces the history of drug policy since Hong Kong became a colony of Britain in the nineteenth century, and then highlights the major drug issues that have emerged in the past several decades. Drug policy in Hong Kong has gone through three stages, from “Government Opium Monopoly” (1841–1945) to “The Prohibition Era” (1946–1960) to “Enlightened Prohibition” (1961–1995). The evolution in drug policy is analyzed in the light of both domestic and international social, economic, and political forces affecting Hong Kong. The major drug issue in the past two decades has been the trends of rising levels of drug use among young people and the increasing popularity of psychoactive drugs among young drug users. It is argued that these trends may be understood in terms of rapid social change resulting from industrialization and socioeconomic growth since the 1960s, and the presence of conditions favorable to the demand and supply of psychoactive drugs. Lastly, major challenges to future drug policy in Hong Kong are discussed. [Translations are provided in the International Abstracts Section of this issue.]     

Trends in Illicit Drug use in the United States: Conflicting Results from National Surveys

Data from several national studies lead to divergent conclusions regarding trends in illicit drug use in the United States. Two major population studies point to a downturn in drug use dating to the late 1970s. However, a study of drug-related deaths and hospital emergency room visits shows increases in these events in recent years. Studies also show drug use, especially cocaine, continuing to increase among criminals. Additionally, drugs were identified as the most important problem facing the nation in a Gallup poll conducted during the summer of 1989. This paper offers some possible explanations for the divergent trends. Most notably, we suggest that methodological differences in the studies being compared, and lags between trends in the general population and certain subgroups, account for most of the variation in the trend estimates. The paper concludes that illicit drug use is decreasing in the United States.     

黏质沙雷菌耐药性及碳青霉烯类抗生素耐药机制研究

目的 探讨黏质沙雷菌分离株的整体耐药特点,研究其对碳青霉烯类药物耐药的主要机制.方法 收集2007至2010年从宁波市第一医院不同病区分离(剔除重复菌株)黏质沙雷菌247株,用Vitek2 -Compact及配套革兰阴性杆菌药敏卡(GNS)检测其药敏情况,对筛选出的20株耐碳青霉烯类菌株进行PCR检测其耐药基因.结果 黏质沙雷菌对头孢曲松、氨曲南、环丙沙星的耐药率较高,分别为70.4％( 174/247)、64.8％ (160/247)、57.4％ (142/247)；对阿米卡星、庆大霉素、亚胺培南、美罗培南的耐药率较低,分别为:3.5％( 8/229)、5.4％( 13/241)、5.9％(14/237)、8.1％ (20/247).PCR检测20株对碳青霉烯类抗生素耐药的黏质沙雷菌中,1、7、12和16号的AmpC染色体基因表达是阴性参考菌株的98.3、102.3、121.5、87.3倍；共有12株黏质沙雷菌分离株同时携带CTX-M型超广谱β内酰胺酶(ESBLs)和KPC-2型碳青霉烯类酶.黏质沙雷菌所携带的CTX-M以CTX-M1、CTX-M2、CTX-M9为主；2株菌携带有SHV基因；2株菌携带有SME基因；2株菌携带有TEM基因；5株菌膜孔蛋白基因ompC和ompF均缺失；仅1株ompC基因缺失；2株菌ompF基因缺失.结论 黏质沙雷菌对β内酰胺类药物耐药的原因比较复杂,以产β内酰胺酶为主.开展对耐药菌株的进化和多耐药基因的研究,有利于合理应用抗菌药物,降低抗生索对耐药菌的选择压力及控制耐药菌株的蔓延.     

尼古丁对大鼠海洛因辨别刺激的替代效应

目的 在建立大鼠海洛因辨别刺激模型基础上,评估不同浓度的尼古丁对海洛因辨别刺激的替代作用.方法 采用固定比率食物强化方法训练雄性SD大鼠辨别0.3 mg/kg海洛因；之后,分别给予不同剂量的海洛因、尼古丁替代0.3 mg/kg海洛因,明确海洛因辨别效应曲线和尼古丁替代0.3 mg/kg海洛因的辨别效应.结果 0.3 mg/kg剂量的海洛因能形成稳定的大鼠药物辨别行为；不同剂量海洛因替代组(0.03,0.1,0.3,0.56 mg/kg)的海洛因鼻触响应率分别为(33.9±15.0)％,(43.3±13.3)％,(98.7±0.5)％,(99.4±0.2)％,海洛因剂量在0～0.3mg/kg之间诱导的辨别效应呈剂量依赖性增加；0.03,0.1mg／kg尼古丁替代组的海洛因鼻触响应率分别为(1.9±1.1)％,(13.7±5.6)％,与0.3mg/kg海洛因替代组相比,差异有统计学意义(P＜0.01)；而0.3,0.5mg/kg尼古丁替代组的海洛因鼻触响应率分别为(60.4±16.1)％,(65.9±16.4)％,与0.3mg/kg海洛因替代组相比,差异无统计学意义(P＞0.05).结论 0.3,0.5 mg/kg尼古丁能产生部分类似海洛因的辨别刺激效应.     

The utilization of Arabic online drug information among adults in Saudi Arabia

In Saudi Arabia, the utilization of the world wide web has become increasingly popular. However, the exact figure of such use is unknown. This study aimed to determine the percentage of, and experience with, online Arabic drug information by Arabic-speaking adults in Saudi Arabia. A web based questionnaire was used. The questionnaire language was Arabic. Public were invited to participate in the survey through e-mails, Twitter, WhatsApp and Facebook in March 2012. The survey included 17 items examining the types of accessed Arabic drug information, the respondent’s demographics, their ability to easily find and understand Arabic drug-related information, and their trustfulness and dependency on such information websites. Of the 422 Arabic speaking adults who answered the questionnaire, 88% stated that they used Arabic websites to answer drug-related questions. Of the respondents, 50% had a bachelor’s degree, 44% were young adults, over half were female (60%), and 72% of them have a chronic disease. The ease of retrieving online information was the most common reason (69%) for consulting such websites. Google as a search engine was the most frequently (86%) accessible website. Although respondents reported different drug-related topics in their online searching, the search for adverse effects was the most common (68%). Respondents claimed that they could easily find (65%) and understand (49%) the drug-related information. Although a good number of respondents qualified this type of information as good, double-checking of information on other websites was highly recommended. Trustfulness was one of the important parameters to measure and 205 respondents (55%) claimed that they only trusted half of the information cited. Moreover, around 48% of respondents considered that finding the same information on more than one website increased its trustfulness. Surprisingly, 54% of respondents did not depend on Arabic information websites when making decisions on drug use. There are a high proportion of Arabic speaking people in Saudi Arabia using and consulting Arabic drug information websites. This information is easily found and understood. However, the quality and trustfulness of such websites are not high enough to depend on them. A qualified Arabic drug information website is important to meet this need.     

某医院常见革兰阴性杆菌的分布与药敏分析

目的 了解珠海市人民医院2009~2010年住院患者常见的菌群分布及其耐药性,为细菌性感染的诊治提供参考依据.方法 用生物梅里埃公司的ATB鉴定系统进行菌种鉴定和药敏试验,用ATBPLUS VER3.0软件统计分析结果.结果 2009~2010年共分离出革兰阴性杆菌3 032株,其中铜绿假单胞菌占29.55%,肺炎克雷伯菌占33.44%,大肠埃希菌占27.51%,阴沟肠杆菌占5.80%,其他革兰阴性杆菌占3.70%.铜绿假单胞菌耐药率高于60%的抗菌药物有头孢噻吩、头孢噻肟、头孢西丁.肺炎克雷伯菌对美罗培南、亚胺培南、头孢吡肟、阿米卡星菌、妥布霉素、哌拉西林/三唑巴坦敏感.大肠埃希菌对第三代头孢菌素、氟喹诺酮类的耐药率增高,对亚胺培南、美罗培南、阿米卡星敏感,对哌拉西林/三唑巴坦、头孢他啶及奈替米星较敏感.阴沟肠杆菌呈多重耐药.结论 该地区常见革兰阴性杆菌的构成比及耐药率和国内其他地区有一定的差异,且细菌多重耐药情况更为严重.