《现代生物医学进展》2021年封面设计说明

2019年底爆发的新冠肺炎疫情肆虐全球,对全球政治、经济、贸易和社会各层次造成了巨大冲击,到目前为止,全球新冠病毒感染人数累计达81715247人,死亡人数达1778294人。因此,本年度封面形象的以新冠病毒肆虐地球,人类重拳出击抵抗新冠疫情为主题设计了封面,旨在倡导生物医学工作者思考和研究更有效的预防和治疗措施以应对新冠病毒。当前,隔离仍然是遏制新冠病毒快速传播的有效手段,新冠疫苗研发与接种是克制新冠疫情的内生动力,而环境消杀是彻底消灭新冠病毒的有力保障。相信通过人类共同努力,各国携手合作,众志成城,一定能够消灭新冠疫情,开创人类命运共同体的美好明天。     

不同消毒方法对家蚕微粒子的存活和侵染力影响

家蚕微粒子病是家蚕Bombyx mori的重要病害,探索其消毒杀灭方法对蚕业生产具有重要意义。本研究采用微粒子染色法和添食家蚕侵染法测试了温度、紫外线和消毒剂处理108个/mL家蚕微粒子后对家蚕微粒子的消杀作用,结果表明：温度对家蚕微粒子虫灭活温度为60℃处理30 min以上;使用20 wx功率紫外灯距离50 cm照射12 min及以上时,微粒子死亡率为47.70%,对家蚕侵染率为0;三氯异氰脲酸800 mg/L及以上浓度处理6 min以上家蚕微粒子死亡率为100%,对家蚕的侵染率为0;戊二醛癸甲溴铵200 mg/L及以上浓度处理6 min以上家蚕微粒子死亡率为100%,对家蚕的侵染率为0。3种消毒方法中温度法主要用于小型蚕具消杀微粒子;紫外线用于蚕业辅助设施的表面微粒子的消杀;三氯异氰脲酸和戊二醛癸甲溴铵均表现出较好的消杀效果,其中戊二醛癸甲溴铵较含氯的消毒剂三氯异氰脲酸稳定性强,刺激性小,对养蚕的金属腐蚀性小,可作为含氯消毒剂的部分替代使用。本研究结果可为蚕业生产中消杀微粒子提供参考。     

SARS-CoV-2污染的进口冷链产品导致的一起大连本土新冠疫情

2020年12月15日,大连市报告了4名码头冷链货物搬运工人SARS-CoV-2核酸检测呈阳性,在此之前,大连市已经连续136天没有报告本土病例.在这次大连COVID-19疫情(简称"大连新冠疫情")中,我们收集了2020年12月15日至2021年1月8日期间大连新冠疫情中全部感染者(83)及部分接触的轮船货物样本,其中确诊病例占61.45％(51/83),无症状感染者占38.55％(32/83).通过高通量测序,共获得76条SARS-CoV-2全基因组序列,其中72条(86.75％,72/83)来自临床样本,4条来自R国籍A货船上的冷链食品外包装样本.基因组分析数据显示,与武汉参考株(NC_045512)相比,76条全基因组分别存在12～16个核苷酸突变位点,共享12个核苷酸突变位点,符合B.1.1进化分支突变特征.结合病毒基因组学和现场流行病学调查结果综合分析表明,大连新冠疫情是一起由SARS-CoV-2污染的进口冷链产品感染码头工人导致的本土疫情,在传播过程中至少形成了3个病毒代际和3个相对独立的传播链.     

基于原子力显微镜的溶液环境下单个天然状态病毒颗粒多参数成像及纳米力学特性分析（英文）

目的 研究单个病毒颗粒的行为特性对于揭示调控病毒生命周期的内在机制、发展新型抗病毒治疗方法具有重要基础意义。原子力显微镜（AFM）的出现为高分辨率探测单个病毒颗粒的结构和力学特性提供了新的强大工具,极大地促进了物理病毒学的发展。然而,目前人们对于力学特性在病毒生命活动过程中调控作用的认知仍然很不足,特别是利用多参数AFM成像技术对病毒颗粒开展的研究还不多见。本文结合AFM多参数成像技术和压痕实验技术研究了溶液环境下化学刺激诱导的单个天然状态病毒颗粒结构及力学特性动态变化。方法 通过在盖玻片基底表面覆盖一层多聚赖氨酸以将慢病毒颗粒吸附到基底,随后利用AFM直接在溶液环境下对天然状态的单个病毒颗粒进行探测。基于AFM峰值力轻敲（PFT）多参数成像模式,同时获取单个病毒颗粒的形貌结构及力学特性图。在AFM形貌图导引下控制AFM探针移动至单个病毒颗粒中央部位进行压痕实验以测量病毒力学特性。利用75%酒精溶液对病毒颗粒进行处理后,对病毒颗粒的形貌结构及力学特性变化情况进行观测。结果 利用AFM在溶液环境下可对单个病毒颗粒的形貌及力学特性进行高质量成像表征,实验结果显示病毒颗粒在空气中和溶液中分别...     

腮腺炎病毒三种实验室常规灭活方法效果评价

探究几种实验室常规消毒灭活方法对腮腺炎病毒的灭活效果,为实验室进行腮腺炎病毒消毒工作提供基础数据。本研究采用热灭活、紫外线灭活和化学试剂灭活三种方法对腮腺炎病毒进行灭活处理,灭活处理后腮腺炎病毒采用细胞培养技术进行病毒滴定,评估上述灭活方法对腮腺炎病毒的灭活效果。热灭活方法显示,腮腺炎病毒对热敏感,随温度升高和热灭活时间增长对腮腺炎病毒灭活有明显加强作用。65℃30min、60min和70℃10min、30min、60min可有效灭活腮腺炎病毒;紫外线灭活方法显示,紫外线照射15min,30min,60min均可有效灭活涂抹在平皿表面的腮腺炎病毒,但对毒株液倾倒导致的MuV液体不能达到完全灭活效果;化学试剂灭活方法显示,三氯异氰泡腾片、1%过氧化氢、3%过氧化氢和75%乙醇根据试剂说明书处理后病毒均能有效灭活腮腺炎病毒。三种灭活方法在一定条件下均能实现对腮腺炎病毒的灭活,可以作为实验室常规灭活腮腺炎病毒方法。建议使用65℃30min或70℃10min对腮腺炎病毒进行有效灭活。紫外线适用于对腮腺炎病毒进行表面消毒,但对液滴状病毒污染建议使用化学试剂进行有效灭活。     

TMV在不同水体与温度条件下的灭活动力学

了解植物病毒在不同水体与温度条件下的灭活规律具有重要的理论与实际意义.本文以典型植物病毒烟草花叶病毒(TMV)为模型,比较了其在不同温度条件下,在闽江水、自来水、生活污水、微孔滤膜过滤除菌污水及超纯水中的灭活动力学.结果显示,温度是导致TMV灭活的重要因素,水温升高,病毒灭活速率加快;此外,某些水质因子也影响TMV的灭活效率,其中可溶性盐的存在及其含量对TMV的灭活会因所处的环境不同而异;某些微生物或代谢产物对植物病毒TMV具有灭活作用,而能生化降解的有机质加速TMV灭活可能是通过促进水体中的微生物增殖而起作用.     

TMV在不同水体与温度条件下的灭活动力学

了解植物病毒在不同水体与温度条件下的灭活规律具有重要的理论与实际意义。本文以典型植物病毒烟草花叶病毒(TMV)为模型,比较了其在不同温度条件下,在闽江水、自来水、生活污水、微孔滤膜过滤除菌污水及超纯水中的灭活动力学。结果显示,温度是导致TMV灭活的重要因素,水温升高,病毒灭活速率加快;此外,某些水质因子也影响TMV的灭活效率,其中可溶性盐的存在及其含量对TMV的灭活会因所处的环境不同而异;某些微生物或代谢产物对植物病毒TMV具有灭活作用,而能生化降解的有机质加速TMV灭活可能是通过促进水体中的微生物增殖而起作用。     

新冠肺炎疫情期间人群心理焦虑抑郁水平与差异分析及与SARS等疫情特点对比

自2019年末,新型冠状病毒肺炎(corona virus disease 2019, COVID-19)疫情在武汉发生以来,我国医疗卫生事业经历着巨大的考验,除了关注新冠肺炎治疗效果、预防措施等之外,人群在疫情下的心理健康状态也值得重视。为了调查疫情期间人群心理状态及相关影响因素,并与既往严重急性呼吸综合征(severe acute respiratory syndrome, SARS)等疫情环境下的特点对比,本研究将自编调查表与已有信效度良好的量表整合,制成问卷,进行网络平台随机发放并抽样调查。结果发现,新冠肺炎疫情下人群焦虑检出率为24.49%,抑郁检出率为50.92%;焦虑及抑郁水平均呈现无差别群体性,结果均具有统计学意义;与SARS相比, COVID-19的传染力更强、传播范围更广,同时疫情期间国家管控规模更大。总的来讲,新冠肺炎疫情对人群心理状态影响呈现无差别群体性,初步推测疫情本身并不是造成心理影响的主要因素,还应考虑长期居家、经济影响等社会因素,加强对人群心理状态的监测和疏导。此外,本文从突发原因、疫情严重程度、国家响应等方面比较了新冠肺炎疫情与SARS等既往传染病疫情的异同,提供了更加科学全面的疫情防控研究视角。     

新冠疫情对全球生物多样性热点地区森林面积的影响

森林是维持生物多样性的重要保障,森林面积的损失常常会导致区域生物多样性的降低或丧失。为探讨新冠疫情对全球生物多样性的影响,该文利用Image J软件筛选出全球生物多样性热点地区占国土面积超60%的国家作为研究对象,以全球生物多样性热点地区的森林损失面积、生物多样性完整性数据、年度(2020年和2021年)新冠疫情感染数据、国内生产总值(GDP)为研究对象,进行关联分析、线性混合效应模型构建和回归预测。结果表明:虽然新冠病毒的每百万人口感染数量与森林损失面积表现为显著负相关,具体表现为新冠疫情显著减少了因城市和农业大规模扩张而导致的森林损失面积,但在新冠疫情暴发的2年(2020年和2021年)期间,全球生物多样性热点地区的森林损失总量仍然持续上升,主要原因是新冠疫情间接加速了人工林和天然林的采伐。回归模型预测显示,新冠疫情期间,全球生物多样性热点地区的森林损失面积在2020年和2021年分别增加了5.83%和21.78%。综上表明,虽然新冠疫情对生物多样性热点地区的森林损失具有一定的抑制作用,但森林损失面积仍然在增加。该研究结果为制定生物多样性的保护措施提供了数据支撑。     

消杀型纳米催化剂抗病毒作用的研究

本文探讨112种消杀型纳米催化剂吸附与灭活病毒的功效,为开发新型抗病毒纳米材料提供理论依据.我们将各种纳米催化剂与副流感病毒、人疱疹病毒Ⅰ型、腺病毒1型及5型作用一定时间后,分别以血凝试验及观察CPE变化的方法判断纳米材料对各种病毒的吸附与灭活作用,并在电子显微镜下观察纳米材料对病毒的吸附情况.结果在所检测的112种纳米催化剂中,用血凝试验分别筛选出强吸附力催化剂29种、中吸附力催化剂36种、弱吸附力催化剂47种.其中,13种强吸附力催化剂对副流感病毒的吸附率在87.5%～93.75%之间,并以AB-24的抗病毒效果最好.     

南方红豆杉内生真菌分离时的表面消毒方法探索

表面消毒是植物内生菌分离的关键环节,在南方红豆杉(Taxus chinensis var. mairei)内生真菌分离的过程中,使用75％乙醇、2％次氯酸钠（NaClO）代替升汞对外植体进行了表面消毒摸索。结果显示：红豆杉叶、茎、皮经预处理后,先用75％乙醇浸泡3 min,再用2％次氯酸钠浸泡2 min,然后红豆杉叶、茎、皮分别用75％乙醇浸泡3 min、5 min、7 min,可取得满意的表面消毒效果。     

Wide variation in effectiveness of laboratory disinfectants against bacteriophages

Aims: The purpose of this study was to identify an effective disinfectant for the inactivation of the bacteriophages (phages) being used in our laboratory, as published studies on phage inactivation are far from unanimous in their conclusions. Methods and Results: The phages studied were three closely related strains of Myoviridae and three strains of Siphoviridae. Three disinfectants which are used commonly in microbiology laboratories were evaluated: Virkon (1%), ethanol (75%) and sodium hypochlorite (2500 ppm available chlorine). The most effective of these was Virkon, which inactivated all six phages rapidly. Ethanol was effective against the Myoviridae but had little effect on the Siphoviridae. Sodium hypochlorite was the least effective of the disinfectants evaluated. Conclusions: The findings of this study demonstrate a wide diversity in the effectiveness of disinfectants tested for inactivation of phages. Significance and Impact of the Study: Of the disinfectants tested Virkon is the most suitable choice for those unable to carry out disinfection validation studies, or where a broad spectrum disinfectant against phages is required. All of the phages in this study showed resilience to inactivation by sodium hypochlorite, and therefore this disinfectant is an unwise choice for use against phage without first assessing its effectiveness.     

Inactivation of Bacillus anthracis spores by liquid biocides in the presence of food residue

Biocide inactivation of Bacillus anthracis spores in the presence of food residues after a 10-min treatment time was investigated. Spores of nonvirulent Bacillus anthracis strains 7702, ANR-1, and 9131 were mixed with water, flour paste, whole milk, or egg yolk emulsion and dried onto stainless-steel carriers. The carriers were exposed to various concentrations of peroxyacetic acid, sodium hypochlorite (NaOCl), or hydrogen peroxide (H(2)O(2)) for 10 min at 10, 20, or 30 degrees C, after which time the survivors were quantified. The relationship between peroxyacetic acid concentration, H(2)O(2) concentration, and spore inactivation followed a sigmoid curve that was accurately described using a four-parameter logistic model. At 20 degrees C, the minimum concentrations of peroxyacetic acid, H(2)O(2), and NaOCl (as total available chlorine) predicted to inactivate 6 log(10) CFU of B. anthracis spores with no food residue present were 1.05, 23.0, and 0.78%, respectively. At 10 degrees C, sodium hypochlorite at 5% total available chlorine did not inactivate more than 4 log(10) CFU. The presence of the food residues had only a minimal effect on peroxyacetic acid and H(2)O(2) sporicidal efficacy, but the efficacy of sodium hypochlorite was markedly inhibited by whole-milk and egg yolk residues. Sodium hypochlorite at 5% total available chlorine provided no greater than a 2-log(10) CFU reduction when spores were in the presence of egg yolk residue. This research provides new information regarding the usefulness of peroxygen biocides for B. anthracis spore inactivation when food residue is present. This work also provides guidance for adjusting decontamination procedures for food-soiled and cold surfaces.     

Inactivation of caliciviruses

The viruses most commonly associated with food- and waterborne outbreaks of gastroenteritis are the noroviruses. The lack of a culture method for noroviruses warrants the use of cultivable model viruses to gain more insight on their transmission routes and inactivation methods. We studied the inactivation of the reported enteric canine calicivirus no. 48 (CaCV) and the respiratory feline calicivirus F9 (FeCV) and correlated inactivation to reduction in PCR units of FeCV, CaCV, and a norovirus. Inactivation of suspended viruses was temperature and time dependent in the range from 0 to 100 degrees C. UV-B radiation from 0 to 150 mJ/cm(2) caused dose-dependent inactivation, with a 3 D (D = 1 log(10)) reduction in infectivity at 34 mJ/cm(2) for both viruses. Inactivation by 70% ethanol was inefficient, with only 3 D reduction after 30 min. Sodium hypochlorite solutions were only effective at >300 ppm. FeCV showed a higher stability at pH <3 and pH >7 than CaCV. For all treatments, detection of viral RNA underestimated the reduction in viral infectivity. Norovirus was never more sensitive than the animal caliciviruses and profoundly more resistant to low and high pH. Overall, both animal viruses showed similar inactivation profiles when exposed to heat or UV-B radiation or when incubated in ethanol or hypochlorite. The low stability of CaCV at low pH suggests that this is not a typical enteric (calici-) virus. The incomplete inactivation by ethanol and the high hypochlorite concentration needed for sufficient virus inactivation point to a concern for decontamination of fomites and surfaces contaminated with noroviruses and virus-safe water.     

Effects of disinfectants against norovirus virus‐like particles predict norovirus inactivation

Human noroviruses (NoVs) are a major cause of epidemic and sporadic acute gastroenteritis worldwide. Public and personal hygiene is one of the most important countermeasures for preventing spread of NoV infection. However, no a practicable cell culture system for NoV had been developed, initial tests of the virucidal effectiveness of anti‐NoV disinfectants and sanitizers have been performed using surrogate viruses. In this study, NoV virus‐like particles (VLPs) were used as a new surrogate for NoVs and a method for evaluating NoV inactivation using them developed. This method is based on morphological changes in VLPs after treatment with sodium hypochlorite. VLP specimens were found to become deformed and degraded in a concentration‐dependent manner. Based on these results, the effects of sodium hypochlorite on VLPs were classified into four phases according to morphological changes and number of particles. Using the criteria thus established, the efficacy of ethanol, carbonates and alkali solutions against VLPs was evaluated. Deformation and aggregation of VLPs were observed after treatment with these disinfectants under specific conditions. To determine the degradation mechanism(s), VLPs were examined by SDS‐PAGE and immunoblotting after treatment with sodium hypochlorite and ethanol. The band corresponding to the major capsid protein, VP1, was not detected after treatment with sodium hypochlorite at concentrations greater than 500 ppm, but remained after treatment with ethanol. These results suggest that VLPs have excellent potential as a surrogate marker for NoVs and can be used in initial virucidal effectiveness tests to determine the mechanism(s) of chemical agents on NoVs.     

Fungicidal effects of chemical disinfectants, UV light, desiccation and heat on the amphibian chytrid Batrachochytrium dendrobatidis

The efficacy of a number of disinfection treatments was tested on in vitro cultures of the fungus Batrachochytrium dendrobatidis, the causative agent of chytridiomycosis in amphibians. The aim was to evaluate the fungicidal effects of chemical disinfectants, sterilising ultraviolet (UV) light, heat and desiccation, using methods that were feasible for either disinfection in the field, in amphibian husbandry or in the laboratory. The chemical disinfectants tested were: sodium chloride, household bleach (active ingredient: sodium hypochlorite), potassium permanganate, formaldehyde solution, Path-X agricultural disinfectant (active ingredient: didecyl dimethyl ammonium chloride, DDAC), quaternary ammonium compound 128 (DDAC), Dithane, Virkon, ethanol and benzalkonium chloride. In 2 series of experiments using separate isolates of B. dendrobatidis, the fungicidal effect was evaluated for various time periods and at a range of chemical concentrations. The end point measured was death of 100% of zoospores and zoosporangia. Nearly all chemical disinfectants resulted in 100%, mortality for at least one of the concentrations tested. However, concentration and time of exposure was critical for most chemicals. Exposure to 70% ethanol, 1 mg Virkon ml(-1) or 1 mg benzalkonium chloride ml(-1) resulted in death of all zoosporangia after 20 s. The most effective products for field use were Path-X and the quaternary ammonium compound 128, which can be used at dilutions containing low levels (e.g. 0.012 or 0.008%, respectively) of the active compound didecyl dimethyl ammonium chloride. Bleach, containing the active ingredient sodium hypochlorite, was effective at concentrations of 1% sodium hypochlorite and above. Cultures did not survive complete drying, which occurred after <3 h at room temperature. B. dendrobatidis was sensitive to heating, and within 4 h at 37 degrees C, 30 min at 47 degrees C and 5 min at 60 degrees C, 100% mortality occurred. UV light (at 1000 mW m(-2) with a wavelength of 254 nm) was ineffective at killing B. dendrobatidis in culture.     

Hypochlorite inactivation kinetics of Listeria monocytogenes in phosphate buffer

The inactivation kinetics of Listeria monocytogenes in a phosphate buffer (PB) was determined at different hypochlorite concentrations, pH values and temperatures. D-values, using a linear regression, of L. monocytogenes in PB (pH 6.5) were 23.54, 17.40, 14.24 and 12.00s at 5, 10, 50 and 100 mg l(-1) hypochlorite, respectively, at 30 degrees C. The k-values ranged from 0.098 to 0.192s(-1) and 0.007 to 0.018s(-1) for hypochlorite concentrations (from 5 to 100 mg l(-1)) in PB (pH 6.5) and PB containing 0.1% peptone (pH 6.5), respectively, at 30 degrees C. D-values of L. monocytogenes exposed to hypochlorite were decreased with decreasing pH of PB (pH from 8.5 to 4.5). Hypochlorite showed higher antimicrobial activity at higher temperature. Not only the effect of hypochlorite concentration on the inactivation of L. monocytogenes but also other parameters like temperature, pH and suspending solutions effect the inactivation rates.     

Inactivation of Caliciviruses

The viruses most commonly associated with food- and waterborne outbreaks of gastroenteritis are the noroviruses. The lack of a culture method for noroviruses warrants the use of cultivable model viruses to gain more insight on their transmission routes and inactivation methods. We studied the inactivation of the reported enteric canine calicivirus no. 48 (CaCV) and the respiratory feline calicivirus F9 (FeCV) and correlated inactivation to reduction in PCR units of FeCV, CaCV, and a norovirus. Inactivation of suspended viruses was temperature and time dependent in the range from 0 to 100°C. UV-B radiation from 0 to 150 mJ/cm² caused dose-dependent inactivation, with a 3 D (D = 1 log₁₀) reduction in infectivity at 34 mJ/cm² for both viruses. Inactivation by 70% ethanol was inefficient, with only 3 D reduction after 30 min. Sodium hypochlorite solutions were only effective at >300 ppm. FeCV showed a higher stability at pH <3 and pH >7 than CaCV. For all treatments, detection of viral RNA underestimated the reduction in viral infectivity. Norovirus was never more sensitive than the animal caliciviruses and profoundly more resistant to low and high pH. Overall, both animal viruses showed similar inactivation profiles when exposed to heat or UV-B radiation or when incubated in ethanol or hypochlorite. The low stability of CaCV at low pH suggests that this is not a typical enteric (calici-) virus. The incomplete inactivation by ethanol and the high hypochlorite concentration needed for sufficient virus inactivation point to a concern for decontamination of fomites and surfaces contaminated with noroviruses and virus-safe water.     

The Effect of Sodium Hypochlorite on Germination of Lettuce Seed at High Temperature

Investigations into the effects of treatment with sodium hypochloritesolution on high-temperature germination of lettuce seed aredescribed. A 2 h treatment in a solution with 10% availablechlorine enabled up to c. 70% of seeds to germinate at 35 °C,without impairing germination and normal seedling developmentat 20 °C. A 10 min rinse in 0.01 N HCI following such treatmentenhanced its effect and treated seeds retained their abilityto germinate at high temperature for at least 18 months. Seedlingdevelopment at 20 °C following treatment was influencedby treatment temperature and batch of hypochlorite solution.Emergence from compost in a cycling (30/15 °C) temperatureregime was improved in three out of five cultivars tested, andthere were indications that hypochlorite treatment enabled oneof the other cultivars to escape induced thermodormancy. Key words: Lactuca sativa L., Sodium hypochlorite, Thermo-inhibition     

Development of a Simple Culture Method for the Tissues Contaminated with Microorganisms and Application to Establishment of a Fish Cell line

Cell cultures are good in vitro model systems in place of using living animals. In the present study, we developed a simple culture method in which tissues were pretreated with a low concentration of sodium hypochlorite solution (NaClO) to prevent not only bacteria but also fungi. Scales removed from a goldfish (Carassius auratus) body were treated with 70% ethanol and then with 0.3% of sodium hypochlorite solution, and cultured in vitro in an atmosphere containing 0.5% CO2. The doubling time of the established cells (GAKS) was 24 hr. The GAKS cells contained alkaline phosphatase activity (8.3+/-1.1 nmol/min/mg protein) and secreted 0.32+/-0.07 pg/ml endothelin during a 3 day culture of a full monolayer sheet.