CD13抑制剂乌苯美司对A549细胞顺铂敏感性的影响及其机制

  目的   检测CD13抑制剂乌苯美司联合顺铂对A549细胞增殖、细胞凋亡的影响,并探讨其机制。   方法   应用噻唑蓝比色法检测细胞增殖;流式细胞Annexin V-FITC/PI双染色法检测细胞凋亡;Western blot方法检测p53、PARP-1、Bcl-2、Bcl2-xL和Caspase蛋白水平;酶活性底物法检测CD13活性;Hoechst33342染色联合流式细胞术检测侧群细胞。   结果   乌苯美司单药对A549细胞增殖无显著影响（P>0.05）,乌苯美司（100 μg/mL）联合顺铂作用A549细胞24、48、72 h后,乌苯美司可显著增强8、16 μmol/L顺铂对A549细胞的增殖抑制（P < 0.05）,并呈时间依赖性,72h时,8、16μmol/L顺铂组和顺铂联合组的细胞增殖率分别为（62.06± 7.60）% vs.（27.92±5.84）%和（19.22±1.57）% vs.（0.67±0.42）%（P < 0.05）;但对64 μmol/L顺铂的细胞增殖率无明显影响（P>0.05）。16 μmol/L顺铂联合组细胞凋亡的比例明显增加（P < 0.05）。乌苯美司对P53、PARP-1、Bcl-2、Bcl2-xL及Capsize蛋白水平无明显影响,但显著抑制A549细胞CD13活性和降低A549侧群细胞比例（P < 0.05）。   结论   CD13抑制剂乌苯美司体外条件下显著提高低剂量顺铂对A549细胞的抑制作用,可能成为CD13阳性非小细胞肺癌患者顺铂的增敏剂。      

浙江省海宁市40~74岁目标人群结直肠癌早诊早治筛查结果分析

[目的]评价海宁市结直肠癌早诊早治筛查效果.[方法]根据《癌症早诊早治项目技术方案》,对40～74岁目标人群采用危险因素量化评估问卷调查和两次大便隐血试验(FOBT)进行初筛,在此基础上,确定结直肠癌高危人群,然后,用电子结肠镜作进一步精筛,对查出的肠道病变进行及时干预.[结果] 2007～2012年海宁市结直肠癌筛查目标人群为322 034人,完成病史问卷调查286 470例,顺应率为88.96％;其中病史阳性16 807例,阳性率为5.87％;两次大便隐血试验461 348份,其中阳性25 928份,阳性率为5.62％.经初筛确定高危人群40 103人需进一步作结肠镜精筛.完成结肠镜检查29 069例,顺应率为72.90％;共检出肠道病变(息肉、腺瘤、癌)7408例,检出率25.48％,其中进展期以上病变1570例.病史阳性占检出病例数的41.10％,FOBT阳性占58.90％,而在205例结直肠癌中FOBT阳性占了91.71％.[结论]结直肠癌筛查成效显著,使无症状的结直肠癌及癌前期病变患者能够实现“三早”,减轻家庭和社会疾病负担.     

上海市真如镇居民肿瘤KAP调查分析

目的:了解上海市真如镇居民关于肿瘤的知识、态度和行为(knowledge,attitudesand practices,KAP),为进一步开展社区肿瘤防治工作提供参考。方法:采用整群抽样方法,以真如镇2个居委30~70岁的常住居民为对象,由经过专业培训的医生,使用统一调查问卷进行入户调查。组间率的比较采用χ2检验。结果:本次研究共调查2695人,有效问卷2610份。男女比例为1∶1·06,平均年龄(53·04±8·70)岁。恶性肿瘤家族史阳性率为22·18%;吸烟率为26·62%;饮酒率为10·34%。居民的KAP水平与年龄、学历、肿瘤家族史和性别相关,差异具有统计学意义,χ2=24·91,P≤0·001。结论:在社区肿瘤防治过程中,针对不同KAP水平的人群有必要采用不同的方法,从而有效地普及防癌抗癌知识,降低癌症的发病率与死亡率,提高居民的生命质量。充分利用社区大众传媒,并争取各部门的协作也是非常重要的。此外,本调查结果显示恶性肿瘤家族史阳性率高达22·18%,可见恶性肿瘤已经和正在对社区居民健康与生命构成重大威胁,必须引起各级医务人员和全社会的高度关注。     

流动人口中艾滋病的防治问题及其应对

随着中国经济的迅速发展,流动人口所占比例迅速增加,而流动人口中的艾滋病防治问题给社会带来了巨大压力;当前多数地区没有真正将流动人口中的艾滋病防治纳入属地化管理的现状,若不尽快从政策、体系和措施上予以积极应对,将会带来严重后果。必须通过艾滋病防治力度的加强和国家的合理部署。有效解决流动人口中艾滋病的防治难题。     

Accumulation and maintenance of information in evolution

Selection accumulates information in the genome—it guides stochastically evolving populations toward states (genotype frequencies) that would be unlikely under neutrality. This can be quantified as the Kullback–Leibler (KL) divergence between the actual distribution of genotype frequencies and the corresponding neutral distribution. First, we show that this population-level information sets an upper bound on the information at the level of genotype and phenotype, limiting how precisely they can be specified by selection. Next, we study how the accumulation and maintenance of information is limited by the cost of selection, measured as the genetic load or the relative fitness variance, both of which we connect to the control-theoretic KL cost of control. The information accumulation rate is upper bounded by the population size times the cost of selection. This bound is very general, and applies across models (Wright–Fisher, Moran, diffusion) and to arbitrary forms of selection, mutation, and recombination. Finally, the cost of maintaining information depends on how it is encoded: Specifying a single allele out of two is expensive, but one bit encoded among many weakly specified loci (as in a polygenic trait) is cheap.

Throughout evolution, selection accumulates information in the genome. It guides evolving populations toward fitter phenotypes, genotypes, and genotype frequencies, which would be highly unlikely to arise by chance. This information—the degree to which selection can control the stochastic process of evolution—has been a long-standing subject of research (1–7), and relates to basic questions in evolutionary biology and genetics.     

Characterization of Inclusion Size Distributions in Steel Wire Rods

The control of inclusions in steel components is essential to guarantee strong performance. The reliable characterization of inclusion populations is essential not only to evaluate the quality of the components but also to allow the use of analytical procedures for the comparison and discrimination of inclusion populations. In this work, inclusion size distributions in wire rod specimens from six plant-scale heats were measured and analyzed. For the measurements, the metallographic procedure specified in the ASTM E2283 standard was used. The population density function (PDF) approach and the extreme value statistical procedure specified in the ASTM E2283 standard were used to analyze the whole size distribution and the upper tail of the size distribution, respectively. The PDF approach allowed us to identify differences among inclusion size distributions and showed that new inclusions were not formed after the liquid steel treatment process. The extreme value statistical procedure led to the prediction of the maximum inclusion length for each heat, which was used for the statistical discrimination of heats. Furthermore, the estimation of the probability of finding an inclusion larger than a given inclusion size using the extreme value theory allowed us to order the heats for different critical inclusion sizes.     

Brief Report: Intrinsic nonlinear dynamics drive single-species systems

The importance of oscillations and deterministic chaos in natural biological systems has been discussed for several decades and was originally based on discrete-time population growth models (May 1974). Recently, all types of nonlinear dynamics were shown for experimental communities where several species interact. Yet, there are no data exhibiting the whole range of nonlinear dynamics for single-species systems without trophic interactions. Up until now, ecological experiments and models ignored the intracellular dimension, which includes multiple nonlinear processes even within one cell type. Here, we show that dynamics of single-species systems of protists in continuous experimental chemostat systems and corresponding continuous-time models reveal typical characteristics of nonlinear dynamics and even deterministic chaos, a very rare discovery. An automatic cell registration enabled a continuous and undisturbed analysis of dynamic behavior with a high temporal resolution. Our simple and general model considering the cell cycle exhibits a remarkable spectrum of dynamic behavior. Chaos-like dynamics were shown in continuous single-species populations in experimental and modeling data on the level of a single type of cells without any external forcing. This study demonstrates how complex processes occurring in single cells influence dynamics on the population level. Nonlinearity should be considered as an important phenomenon in cell biology and single-species dynamics and also, for the maintenance of high biodiversity in nature, a prerequisite for nature conservation.     

Can high COVID-19 vaccination rates in adults help protect unvaccinated children? Evidence from a unique mass vaccination campaign,Schwaz/Austria,March 2021

BackgroundAfter an outbreak of the SARS-CoV-2 Beta variant in the district of Schwaz/Austria, vaccination with Comirnaty vaccine (BNT162b2 mRNA, BioNTech-Pfizer) had been offered to all adult inhabitants (≥ 16 years) in March 2021. This made Schwaz one of the most vaccinated regions in Europe at that time (70% of the adult population took up the offer). In contrast, all other Austrian districts remained with low vaccine coverage.AimWe studied whether this rapid mass vaccination campaign provided indirect protection to unvaccinated individuals such as children (< 16 years) living in the same district.MethodsTo study the effect of the campaign we used two complementary approaches. We compared infection rates among the population of children (< 16 years) in Schwaz with (i) the child population from similar districts (using the synthetic control method), and (ii) with the child population from municipalities along the border of Schwaz not included in the campaign (using an event study approach).ResultsBefore the campaign, we observed very similar infection spread across the cohort of children in Schwaz and the control regions. After the campaign, we found a significant reduction of new cases among children of −64.5% (95%-CI: −82.0 to −30.2%) relative to adjacent border municipalities (using the event study model). Employing the synthetic control method, we observed a significant reduction of −42.8% in the same cohort.ConclusionOur results constitute novel evidence of an indirect protection effect from a group of vaccinated individuals to an unvaccinated group.     

Finger dexterity in well-functioning cohort of office workers in Macau

AimThe study aimed to describe the finger dexterity in office workers of an Asian population.MethodsOne hundred twenty-seven right-handed office workers, aged 21–50 with a similar split of male and female, were recruited with finger dexterity measured by the O’Connor Finger Dexterity Test. The grip strength, tip and lateral pinch strength of both hands were also measured.ResultsThis study provided the percentile score of the O’Connor Finger Dexterity Test of both males and females in the Asian population. Raw scores of below 218 and 213 seconds in male and female participants respectively reach the 90th percentile, and above 237 and 235 seconds in male and female below the 10th percentile. Results showed no significant difference in local mean scores across different age groups, between male and female and with varying hours of working in typing, filing, and writing. A significant difference was only found in finger dexterity and years of working as office workers. No significant correlation was found between the finger dexterity with grip strength, tip and lateral pinch of the dominant right hand. The results were similar to the original normative score with similar work skills and demands.ConclusionThe mean scores could be used as a valid reference for local occupational therapists to evaluate the finger dexterity of office workers. However, caution has to be taken that conclusions drawn can be biased because of the relatively small sample size, and the results cannot be generalized to represent a wider Asian population.