北京市大鼠、小鼠、豚鼠的病理学调查

目的：实验动物的健康状况对科学研究的发展有重要的影响,为了保证实验用鼠的健康质量,自从2009年起本实验室对北京市多家实验动物单位的实验用鼠进行了病理学抽检,从病理学的角度来调查北京市部分实验鼠的主要脏器的情况。方法我们主要对实验鼠的心、肝、脾、肺、肾、大肠和小肠进行取材,通过甲醛固定,石蜡切片HE染色、冰冻切片油红“O”染色、PAS染色等方法对实验用鼠进行病理学分析。结果根据病理学的调查结果,部分实验动物在以肝脏和肾脏为代表的器官中出现了不同程度的病变。结论结合对实验鼠的微生物学检测,分析认为,北京市的啮齿类实验动物中几乎无细菌、病毒和寄生虫等病原微生物的阳性感染个体,对人、动物及周围环境无明显危害;但是少部分实验鼠在临床上出现一定程度的病理学异常。     

ECG 信号QRS 波群检测算法的进展

QRS波群是ECG信号的重要组成部分,是心电信号分析的基础.QRS波群的检测方法已经有很多种实用有效的方法,并逐步地走向成熟,在实际应用中得到实现.本文就QRS波群的检测方法作了具体的整理与分析,较全面的阐述了实际应用中的各种算法,最后作者对检测算法的发展趋势进行了总结和展望.     

儿童传染性单核细胞增多症淋巴细胞亚群的变化及意义

目的 通过对儿童传染性单核细胞增多症(infectious mononucleosis,IM)外周血淋巴细胞亚群的检测,探讨其细胞免疫功能变化与疾病的关系.方法 采用流式细胞仪对35例IM患儿外周血T、B和NK淋巴细胞亚群进行检测,30例健康儿童作为对照组;对患儿中的7例进行治疗2周后细胞亚群的测定以观察动态变化;对患儿进行外周血异型淋巴细胞计数.结果 IM患儿CD3、CD8 T淋巴细胞水平明显升高,CD19、NK、CD4和CD4/CD8值水平明显降低,分别与正常对照组比较差异均有统计学意义.7例IM患儿治疗2周后T细胞亚群的测定值与入院时比较差异有统计学意义,治疗前CD4、CD4/CD8值低于治疗后,治疗前CD8高于治疗后.IM患儿急性期CD8、CD4/CD8水平与患儿外周血异型淋巴细胞百分率(≤10％和＞10％)的差异有统计学意义.结论 检测淋巴细胞亚群对评估IM患儿的细胞免疫状况,辅助诊断和指导治疗具有重要的临床价值.     

四聚体技术在自身免疫性疾病中的运用

自身免疫性T淋巴细胞(autoreactive T cells, ART) 在自身免疫性疾病的发病机制中起着重要作用, 长期以来, 一直缺乏研究这群细胞合适的分析方法.近年来基于TCR特异识别表位肽-MHC复合物的原理发展起来的四聚体(tetramer)技术, 并随着特异性结合亲和力的不断提高, 大大地推进了对ART的研究.MHC-Ⅰ和MHC-Ⅱ四聚体分别用于检测自身免疫性CD4 和CD8 T细胞,而非经典MHC (如CD1d) 四聚体用来检测NKT等其他自身免疫性T细胞.四聚体技术既可对血液和组织中ART直接定量检测, 又可在单个细胞水平上对其表型和功能特征进行分析.另外原位四聚体染色(in situ tetramer staining, ISTS)还可在细胞微环境中对ART进行分析.四聚体技术的运用可望为在阐述自身免疫性疾病机制中ART的作用提供重要信息.     

35GHz高功率毫米波辐照下活鼠体表温升的研究

高功率密度35 GHz毫米波对活体鼠体表的辐照温升的实验结果表明：实验鼠的辐照侧的活体皮肤血液灌注率达到较高的水平;剃毛实验鼠的皮肤表面温升曲线和有毛实验鼠皮肤表面温升曲线类似,但在相同的时刻,前者温升要高于后者.将实验温升曲线和Pennes方程计算结果做了对比,发现：考虑血流灌注的Pennes方程与前16 s左右的剃毛实验鼠实验温升曲线吻合;在16 s之后,无血流灌注的热传导方程计算结果更加靠近剃毛实验鼠实验温升曲线,实验曲线略高于含有较大血流灌注率的理论计算曲线.上述实验现象和理论计算结果差异的可能原因也做了一些简单分析.     

2019年河南省健康人群流行性脑脊髓膜炎A群、C群抗体水平监测

目的了解2019年河南省健康人群流行性脑脊髓膜炎(epidemic cerebrospinal meningitis,简称流脑)A群、C群抗体水平状况,为科学制定防控策略提供依据。方法采用分层随机抽样的方法采集健康人群血清,用间接ELISA检测流脑A群、C群抗体浓度。结果共检测1 689份健康人群血清标本,其中流脑A群抗体阳性率为54.23%,抗体质量浓度中位数为2.18μg/mL;流脑C群抗体阳性率为51.51%,抗体质量浓度中位数为2.07μg/mL。不同地区之间流脑A群、C群抗体水平的差异、阳性率的差异均有统计学意义(P<0.05)。不同年龄组之间流脑A群、C群抗体水平的差异、阳性率的差异均有统计学意义(P<0.05)。结论河南省健康人群流脑A群、C群抗体水平和阳性率都比较低,有发生流脑暴发和流行的血清学基础,应加强流脑监测和预防接种的管理工作。     

乳酸菌在基因工程领域的应用

乳酸菌是工业微生物中一类非常重要的细菌,也是众所周知的维持人及动物健康的重要益生菌群.在最近十几年来,乳酸菌的遗传学和分子生物学特性很受关注,通过对它们进行遗传修饰改造取得了重要成果,扩大了它们的应用.     

贵州小型猪主要病原微生物与寄生虫的控制

封闭群实验用贵州小型猪Sus scrofa domestica var. mino guizhounensis Yu是目前国内最主要的实验用小型猪种群之一(甘世祥, 1994).开展实验动物微生物与寄生虫的控制与监测,对保证实验动物和动物实验的质量和维护人类健康具有重要意义(孙靖,2005).本研究探索了环境消毒、体内外驱虫、疫苗接种等措施对贵州小型猪病原生物的携带和免疫状况的影响.     

湖南省实验动物中几种常见的人兽共患病监测

目的对2003年至2007年湖南省实验动物中沙门氏菌、汉坦病毒、仙台病毒、淋巴细胞脉络丛脑膜炎病毒、弓形虫病等几种常见的人兽共患病的流行病学进行调查。方法按《GB14922．2-2001》和《GB14922．1-2001》抽检动物。结果实验大、小鼠汉坦病毒（HV）和仙台病毒（Sendai）出现抗体阳性,实验小鼠淋巴细胞脉络丛脑膜炎病毒（LCM）出现抗体阳性,实验鼠沙门氏菌（Salmonella）检测结果阳性,实验大鼠和普通级兔弓形体（Toxoplasma）检测结果阳性。结论应加强对实验动物流行病学的监测。     

中缅树鼩自然感染六种病毒的血清流行病学

中缅树鼩作为一种新型实验动物,在医学生物学上,尤其是病毒学方面的应用受到越来越多的重视.实验动物自身病毒感染会影响动物健康和干扰实验结果,甚至危害实验人员生命安全.所以,实验动物病毒检测一直是动物质量控制的重要部分.中缅树鼩研究迄今缺乏清晰的病毒自然感染资料.为调查中缅树鼩的病毒感染状况,采集野生俘获和人工繁殖的中缅树鼩血清样本272份,全部血清样本通过ELISA方法对乙型肝炎病毒(HBV)表面抗原,丙型肝炎病毒(HCV)总抗体,以及戊型肝炎病毒(HEV)、腺病毒(ADV)、单纯疱疹病毒1型(HSV-1)和2型(HSV-2)的IgG抗体进行了检测.结果表明,ELISA初筛HBV表面抗原有3份阳性样本,但通过乙型肝炎两对半定量检测进一步确认为阴性:抗HCV抗体和抗HEV、ADV、HSV-1 IgO抗体检测均为阴性;抗HSV-2 IgG检测有1份阳性样本.提示仪抗原或抗体血清学指标检测树鼩肝炎结果并不能反应个体携带病毒的状态,应该再进行病毒学指标确认.同时建议中缅树嗣繁殖群应进行HSV-2的筛选,以便杜绝和控制该病毒的感染.     

浅谈实验动物病理检测

实验动物病理检测是实验动物质量监督检验的重要环节,病理学研究是对实验动物质量综合评估的最好方法 ,针对目前的检测现状,本文在制定实验动物病理检测标准的重要性、病理检测内容以及检测标准的制定原则方面进行了讨论。     

Rodent quarantine programs: purpose, principles, and practice

In animal research, validity and reproducibility of data are critically influenced by the microbial status of the experimental animals. One of the most crucial aspects of assuring quality in animal research is providing research personnel with confidence that experimental results will not be invalidated due to interference caused by infectious disease. An effective quarantine program is essential to providing this assurance. Quarantine programs are generally instituted to prevent the introduction of rodent pathogens into established specific-pathogen-free colonies in a facility. Therefore, programs should be designed to isolate newly acquired rodents until their health status can be determined and to maximize the probability that microorganisms of interest will be detected before the animals are introduced into (and thus, could potentially contaminate) established colonies. Important principles that are critical to designing an effective quarantine program will be discussed here, as will the practical implementation of these principles. Although quarantine programs may be costly in terms of time and effort, these costs must be balanced against the potential costs of disease outbreaks that could invalidate long-term studies, alter normal biological baselines, and cause the loss or necessitate re-derivation of rare or valuable strains of rodents. Reducing the incidence of quarantine failures through appropriate program design and implementation helps to maintain the confidence of research personnel in the value of quarantine programs and in our competence as specialists in laboratory animal management and as partners in the research process.     

Pneumocystis: newer knowledge about the biology of this group of organisms in laboratory rats and mice

This review is an update on some of the remarkable advances that have led to greater understanding of Pneumocystis, an important group of rodent pathogens. The author outlines the life cycle of these pulmonic fungi, their taxonomic position, and their nomenclature. He discusses how infections begin and spread in laboratory rodent colonies, and how those infections are inadvertently maintained in barriered breeding colonies. He also addresses the diagnosis of Pneumocystis infection and provides suggestions for the establishment of Pneumocystis-free animal colonies.     

Environmental enrichment for laboratory rodents

Modernization of housing and husbandry techniques for rodents has minimized confounding variables. The result has been vastly improved health maintenance and reproducibility of research findings, advances that have decreased the numbers of animals needed to attain statistically significant results. Even though not all aspects of rodent manipulation have been strictly defined, as housing and handling procedures have become increasingly standardized, many animal care personnel have recognized the lack of complexity of the rodents' environment. Concern for this aspect of animal well-being has led many research facilities to provide "environmental enrichment" for rodents. Additionally, regulatory agencies in the United States and Europe have also been increasingly concerned about this issue relative to laboratory animal husbandry. However, little is known about the influence such husbandry modifications may have on biological parameters. In this article, laws and guidelines relating to rodent enrichment are reviewed, the natural behaviors of select rodent species are discussed, and an overview of widely used types of enrichment in laboratory rodent management is provided. The literature evaluating effects of rodent enrichment is reviewed both in terms of neurological development and as an experimental variable, and results of a study evaluating the effect of enrichment on immune and physiological parameters are reported. Survey data on current enrichment practices in a large multi-institutional organization are presented, and practical aspects requiring consideration when devising a rodent enrichment program are discussed.     

The Nile grass rat as a laboratory animal

Rodents are the subjects of the overwhelming majority of laboratory animal studies, and most laboratory rodents are nocturnal. The availability of a suitable diurnal rodent would provide a more effective animal model for biomedical research applicable to humans. The author describes several characteristics of the Nile grass rat that make this diurnal murid rodent an attractive laboratory animal.     

Clinical considerations in rodent bioimaging

Imaging modalities such as micro-computed tomography (micro-CT), micro-positron emission tomography (micro-PET), high-resolution magnetic resonance imaging (MRI), optical imaging, and high-resolution ultrasound are rapidly becoming invaluable research tools. These advanced imaging technologies are now commonly used to investigate rodent biology, metabolism, pharmacokinetics, and disease in vivo. Choosing an appropriate anesthetic regimen as well as monitoring and supporting the animal's physiologic balance is key to obtaining images that truly represent the biologic process or disease state of interest. However, there are many challenges in rodent bioimaging such as limited animal access, small sample volumes, anesthetic complications, strain and gender variability, and the introduction of image artifacts. Because each imaging study presents unique challenges, a thorough understanding of the imaging modality used, the animal's health status, and the research data desired is required. This article addresses these issues along with other common laboratory animal clinical considerations such as biosecurity and radiation safety in in vivo rodent bioimaging.     

Opportunistic infections of mice and rats: Jacoby and Lindsey revisited

Adventitious infections among rodents used in biomedical research and teaching continue to be problematic even with improved housing and disease-deterrent methodologies. In addition to well-documented viral diseases (e.g., mouse hepatitis virus and rodent parvoviruses) and parasites (mites and pinworms), new pathogens such as murine norovirus have emerged in recent years. Infectious agents can enter colonies via incoming rodent shipments, in unscreened biological materials, on people (especially husbandry or investigative staff) who move from a location where animals have a lower health status to an area where health status is higher and operational procedures are more stringent, or by introduction of contaminated food, bedding material, or other fomites. These factors, coupled with the very high volume of movement of rodents within and between institutions, increase the risk of spreading infectious agents. The challenge to the laboratory animal community is to implement control measures that halt the passage of these organisms from one location to another while still enabling collaborative scientific discovery to proceed with minimal disruption. It is therefore critical to make appropriate decisions about identifying outbreaks in a timely fashion and controlling the spread of infection once identified. Such efforts should be practical, reproducible, and cost-effective.     

A serological survey of accredited breeding colonies in the United Kingdom for common rodent viruses.

This paper reports the results of a general survey, the first in the United Kingdom, carried out on accredited breeding colonies of mice, rats and guinea-pigs over a period of a year. While the results show the potential usefulness of a viral accreditation grading scheme, they also show that contamination of breeding colonies with inapparent viral infections is widespread. This situation can only be improved by the continuous monitoring of animal stocks for rodent viruses, with the aim of improving the standard of animals available for research and for pharmacological, toxicological and routine diagnostic procedures.     

New building, old parasite: Mesostigmatid mites--an ever-present threat to barrier facilities

Mesostigmatid mites are blood-sucking parasitic mites found in wild rodent populations. Periodically they can also become a problem for laboratory rodent colonies, particularly when building construction or renovations disturb colonies of commensal (building) rodents that had been acting as hosts. Mesostigmatid mites infest both rats and mice and, unlike the more common rodent fur mites (Myobia, Myocoptes, and Radfordia sp.), can survive for long periods in the environment and travel considerable distances in search of new hosts. They easily penetrate barrier caging systems, including individually ventilated cages, thus circumventing the usual precautions to protect rodents from infection. The two mites reported in laboratory rodent colonies, Ornithonyssus bacoti and Laelaps echidnina, also bite humans and have the potential to transmit zoonotic diseases. Once the mites gain access to a colony, eradication requires elimination of commensal rodent reservoirs in addition to insecticide treatment of both the laboratory rodents and the environment. In view of the undesirability of insecticide use in the animal facility, it is advisable to investigate the effectiveness of preventive treatments, such as environmental application of insect growth regulators or silica-based products. This article summarizes available information on mesostigmatid mites and their laboratory incursions, and provides suggestions for diagnosis, treatment, and control based on the authors experience with several outbreaks at a large academic institution..     

Microbiological monitoring of laboratory mice and biocontainment in individually ventilated cages: a field study

Over recent years, the use of individually ventilated cage (IVC) rack systems in laboratory rodent facilities has increased. Since every cage in an IVC rack may be assumed to be a separate microbiological unit, comprehensive microbiological monitoring of animals kept in IVCs has become a challenging task, which may be addressed by the appropriate use of sentinel mice. Traditionally, these sentinels have been exposed to soiled bedding but more recently, the concept of exposure to exhaust air has been considered. The work reported here was aimed firstly at testing the efficiency of a sentinel-based microbiological monitoring programme under field conditions in a quarantine unit and in a multi-user unit with frequent imports of mouse colonies from various sources. Secondly, it was aimed at determining biocontainment of naturally infected mice kept in an IVC rack, which included breeding of the mice. Sentinels were exposed both to soiled bedding and to exhaust air. The mice which were used in the study carried prevalent infectious agents encountered in research animal facilities including mouse hepatitis virus (MHV), mouse parvovirus (MPV), intestinal flagellates and pinworms. Our data indicate that the sentinel-based health monitoring programme allowed rapid detection of MHV, intestinal flagellates and pinworms investigated by a combination of soiled bedding and exhaust air exposure. MHV was also detected by exposure to exhaust air only. The IVC rack used in this study provided biocontainment when infected mice were kept together with non-infected mice in separate cages in the same IVC rack.