Factors associated with asymptomatic infection in health-care workers with severe acute respiratory syndrome coronavirus 2 infection in Wuhan,China: a multicentre retrospective cohort study

ObjectivesTo describe the fraction of asymptomatic health-care workers (HCWs) in two designated hospitals for coronavirus disease 2019 (COVID-19) treatment in Wuhan and explore the factors associated with asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.MethodsAll HCWs in Wuhan Union Hospital and Wuhan Red Cross Hospital with either positive SARS-CoV-2 nucleic acid or positive antibody test before 18 April 2020 were included. Exposure, epidemiological and demographic information were retrospectively collected by a structured questionnaire. Medical records were also reviewed for clinical characteristics and CT images of HCWs.ResultsAs of 18 April 2020, a total of 424 HCWs were identified. Among them, 276 (65.1%) were symptomatic and 148 (34.9%) were asymptomatic. Fifty-five (19.9%) families of the symptomatic HCWs and 16 (10.8%) families of the asymptomatic HCWs were infected with SARS-CoV-2. HCWs with infected family members tended to be symptomatic (OR 2.053, 95% CI 1.130–3.730; p 0.018). Multivariable logistic regression analysis exhibited that performing tracheal intubation or extubation (OR 4.057, 95% CI 1.183–13.909; p 0.026) was associated with an increased likelihood of symptomatic SARS-CoV-2 infection, whereas consistent use of N95 respirators (OR 0.369, 95% CI 0.201–0.680; p 0.001) and eye protection (OR 0.217, 95% CI 0.116–0.404; p < 0.001) were associated with an increased likelihood of asymptomatic SARS-CoV-2 infection.ConclusionsAsymptomatic SARS-CoV-2 infection in HCWs comprised a considerable proportion of HCW infections during the pandemic of COVID-19. Those who performed tracheal intubation or extubation were most likely to develop related symptoms, whereas those taking aggressive measures, including consistent use of N95 masks and eye protection, tended to be asymptomatic cases.     

Severe acute respiratory syndrome coronavirus 2 causes lung inflammation and injury

BackgroundAs of 14 October 2021, coronavirus disease 2019 (COVID-19) has affected more than 246 million individuals and caused more than 4.9 million deaths worldwide. COVID-19 has caused significant damage to the health, economy and lives of people worldwide. Although severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is not as lethal as SARS coronavirus or Middle East respiratory syndrome coronavirus, its high transmissibility has had disastrous consequences for public health and health-care systems worldwide given the lack of effective treatment at present.ObjectivesTo clarify the mechanisms by which SARS-CoV-2 caused lung inflammation and injury, from the molecular mechanism to lung damage and tissue repair, from research to clinical practice, and then presented clinical requirements.SourcesReferences for this review were identified through searches ‘(COVID-19 [Title]) OR (SARS-CoV-2 [Title])’ on PubMed, and focused on the pathological damage and clinical practice of COVID-19.ContentWe comprehensively reviewed the process of lung inflammation and injury during SARS-CoV-2 infection, including pyroptosis of alveolar epithelial cells, cytokine storm and thrombotic inflammatory mechanisms.ImplicationsThis review describes SARS-CoV-2 in comparison to SARS and explores why most people have mild inflammatory responses, even asymptomatic infections, and only a few develop severe disease. It suggests that future therapeutic strategies may be targeted antiviral therapy, the pathogenic pathways in the lung inflammatory response, and enhancing repair and regeneration in lung injury.     

Detection of severe acute respiratory syndrome coronavirus 2 in nasopharynx according to clinical phenotype of affected patients

ObjectivesDuration of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the upper respiratory tract is extremely variable, but its relation to disease severity is unknown. We investigated this relation in the 530 000 inhabitants of the northeastern Italian province of Udine.MethodsWe analysed real-time RT-PCR tests for SARS-CoV-2 in upper respiratory specimens conducted at the Virology Laboratory of the University Hospital of Udine, Italy (which serves the whole province) from 1 March to 30 April 2020 Specimens were from positive individuals in four groups characterized by different disease severity (critically ill patients admitted to intensive care units, patients admitted to infectious disease units, symptomatic patients visiting the emergency department and not hospitalized, and asymptomatic individuals tested during contact tracing or screening activities). Duration of viral positivity was assessed from the first positive test to the day of the first of two consecutive negative tests. Univariate and multivariate analyses were conducted to investigate differences in the four groups.ResultsFrom 1 March to 30 April, 39 483 RT-PCR tests for SARS-CoV-2 were conducted on 23 778 individuals, and 974 individuals had a positive test result. Among those with multiple tests (n = 878), mean time to negativity was 23.7 days (standard error 0.3639; median 23, interquartile range 16–30 days). Mean time to negativity was longer in the group admitted to the intensive care unit than in the others, whereas no difference was observed between asymptomatic patients and those with mild disease.ConclusionsDisease control measures should not be adjusted to account for differences in viral shedding according to symptomatic status.     

Seroprevalence of severe acute respiratory syndrome coronavirus 2 in Slovenia: results of two rounds of a nationwide population study on a probability-based sample,challenges and lessons learned

ObjectivesSeroprevalence surveys provide crucial information on cumulative severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exposure. This Slovenian nationwide population study is the first longitudinal 6-month serosurvey using probability-based samples across all age categories.MethodsEach participant supplied two blood samples: 1316 samples in April 2020 (first round) and 1211 in October/November 2020 (second round). The first-round sera were tested using Euroimmun Anti-SARS-CoV-2 ELISA IgG (ELISA) and, because of uncertain estimates, were retested using Elecsys Anti-SARS-CoV-2 (Elecsys-N) and Elecsys Anti-SARS-CoV-2 S (Elecsys-S). The second-round sera were concomitantly tested using Elecsys-N/Elecsys-S.ResultsThe populations of both rounds matched the overall population (n = 3000), with minor settlement type and age differences. The first-round seroprevalence corrected for the ELISA manufacturer's specificity was 2.78% (95% highest density interval [HDI] 1.81%–3.80%), corrected using pooled ELISA specificity calculated from published data 0.93% (95% CI 0.00%–2.65%), and based on Elecsys-N/Elecsys-S results 0.87% (95% HDI 0.40%–1.38%). The second-round unadjusted lower limit of seroprevalence on 11 November 2020 was 4.06% (95% HDI 2.97%–5.16%) and on 3 October 2020, unadjusted upper limit was 4.29% (95% HDI 3.18%–5.47%).ConclusionsSARS-CoV-2 seroprevalence in Slovenia increased four-fold from late April to October/November 2020, mainly due to a devastating second wave. Significant logistic/methodological challenges accompanied both rounds. The main lessons learned were a need for caution when relying on manufacturer-generated assay evaluation data, the importance of multiple manufacturer-independent assay performance assessments, the need for concomitant use of highly-specific serological assays targeting different SARS-CoV-2 proteins in serosurveys conducted in low-prevalence settings or during epidemic exponential growth and the usefulness of a Bayesian approach for overcoming complex methodological challenges.     

The potential clinical utility of measuring severe acute respiratory syndrome coronavirus 2-specific T-cell responses

BackgroundBoth humoral and cell-mediated responses are associated with immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although our understanding of the potential role of T-cell responses in the context of coronavirus disease 2019 (COVID-19) is rapidly increasing, more information is still needed.ObjectivesTo provide an overview of the role of T-cell immunity in COVID-19, in the context of natural infection and post-vaccination, and discuss the potential utility of measuring SARS-CoV-2-specific T-cell responses, drawing on experience of the use of interferon-γ release assays (IGRAs) in tuberculosis (TB).SourcesPubMed articles up to 16 April 2021.ContentT-cell responses can be detected very early in the course of COVID-19, earlier than the detection of antibody responses, and are correlated with COVID-19 outcome. Lower CD4⁺ and CD8⁺ T-cell counts are markers of more severe disease, longer duration of viral RNA positivity and increased mortality. In line with natural infection, SARS-CoV-2 vaccination stimulates robust T-cell responses, which probably play an important role in protection; data on long-term T-cell responses are currently limited. The utility of measuring T-cell responses is already well established in both aiding the diagnosis of TB infection using IGRAs, and evaluation of T-cell responses to TB vaccine candidates. A variety of assays have already been developed to measure SARS-CoV-2-specific T-cell responses, including IGRAs, intracellular cytokine staining and activation-induced markers. IGRAs based on SARS-CoV-2 antigens can distinguish between convalescent and uninfected healthy blood donors.ImplicationsSimple assays for measuring the quantity and function of T-cell responses may have utility in the prognostication of COVID-19, and for monitoring immune responses to SARS-CoV-2 vaccination and population-based immunity to SARS-CoV-2 variants of interest.     

Immune responses against severe acute respiratory syndrome coronavirus induced by virus-like particles in mice

Virus-like particles (VLPs) represent a promising vaccine against severe acute respiratory syndrome coronavirus (SARS CoV). In this study, recombinant baculovirus vAcS and vAcME were constructed to express the S protein and the M and E proteins of SARS CoV, respectively. Electron microscope analysis demonstrated the formation of VLPs in vAcME and vAcS coinfected insect cells. Mice immunized four times with VLPs developed high antibody titres against SARS CoV. In addition, VLPs elicited cell-mediated immunity as demonstrated by enhanced interferon-gamma and interleukin-4 production. VLPs also conferred protective immunity against the infection of Spike protein pseudotyped murine leukaemia virus. Our findings demonstrate that SARS CoV VLPs are immunogenic and can elicit strong SARS CoV-specific humoral and cellular immune responses in mice. This is the first study describing the immunogenicity of SARS CoV VLPs, providing valuable data for developing a protective vaccine against SARS CoV infection.     

严重急性呼吸综合征相关冠状病毒的基因检测

目的 研制一项检测严重急性呼吸综合征的即时逆转录-聚合酶链反应(RT-PCR)方法,用于患者全血的检查。方法 内引物和短柄圆环探针(分子信标,molecular beacon)的设计,针对基因库SARS相关冠状病毒的高度保守区(RNA聚合酶基因区),在15301和15480之间(G130027616)。结果 即时RT—PCR荧光测量结果能显示SARS相关冠状病毒特有序列的扩增程度。常规PCR的145bp产物经测序证实与探针杂交的靶序列一致。结论 这一方法的建立对SARS临床诊断和病原研究提供一种快捷和准确的手段。     

严重急性呼吸综合征血细胞动态变化及预测意义

目的探讨严重急性呼吸综合征(SARS)患者血细胞的变化规律,分析SARS预后的临床指征。方法 对43例SAP6患者动态观察血细胞变化规律,做出趋势图,并比较SARS组与正常对照组、SAPS康复组与病死组之间的区别。结果初诊时SARS组白细胞、淋巴细胞、红细胞均低于对照组(P<0.01)差异有显著意义。SARS病死组淋巴细胞和血小板持续降低,康复组则无降低,据此可提示SARS预后。结论动态观察血细胞变化有利于SARS早期诊断及病情预警,从而提示治疗方法,降低病死率。     

Tissue and cellular tropism of the coronavirus associated with severe acute respiratory syndrome: an in-situ hybridization study of fatal cases

Severe acute respiratory syndrome (SARS) is a new human infectious disease with significant morbidity and mortality. The disease has been shown to be associated with a new coronavirus (SARS-CoV). The clinical and epidemiological aspects of SARS have been described. Moreover, the viral genome of SARS-CoV has been fully sequenced. However, much of the biological behaviour of the virus is not known and data on the tissue and cellular tropism of SARS-CoV are limited. In this study, six fatal cases of SARS were investigated for the tissue and cellular tropism of SARS-CoV using an in-situ hybridization (ISH) technique. Among all the tissues studied, positive signals were seen in pneumocytes in the lungs and surface enterocytes in the small bowel. Infected pneumocytes were further confirmed by immunofluorescence-fluorescence in-situ hybridization (FISH) analysis. These results provide important information concerning the tissue tropism of SARS-CoV, which is distinct from previously identified human coronaviruses, and suggest the possible involvement of novel receptors in this infection. Whereas the lung pathology was dominated by diffuse alveolar damage, the gut was relatively intact. These findings indicated that tissue responses to SARS-CoV infection are distinct in different organs.     

抗SARS冠状病毒中和活性单克隆抗体的筛选及其结合位点分析

目的 建立能分泌具有中和活性的抗SARS-CoV单克隆抗体（McAb）细胞株，制备有中和活性的抗SARS-CoV MeAb，用于SARS-CoV感染的早期特异诊断和进行SARS-CoV结构蛋白的功能研究。方法 用灭活纯化sARS-c0V（BJ01株）免疫BALB／c小鼠，通过细胞融合技术，建立能稳定分泌SAILS病毒MeAb的杂交瘤细胞系，然后用中和试验进一步筛选分泌具有中和活性的抗SARS-CoV MeAb细胞株。利用SARS-CoV的S和N蛋白的不同长度肽段通过EusA鉴定McAb的特异结合区域，分析S和N蛋白不同区域诱导产生抗体的能力和特性。结果 建立了12株能稳定分泌抗SARS-CoV McAb的杂交瘤细胞株，间接免疫荧光法检测抗体效价在1：320～1：20 480之间，其中6株具有较好的中和SARS-CoV的能力。具有中和活性的McAb中，3株是针对S蛋白的，2株是针对N蛋白的。其中抗S蛋白的中和抗体活性比抗N蛋白的中和抗体活性高，另外1株可能是针对SARS-CoV的其他结构蛋白的。进一步对6株抗S蛋白的McAb的特异抗原结合表位分析，发现其中3株结合位点在S蛋白第12～311氨基酸之间，2株在第310～535氨基酸之间，后者中和效价高于前者，另1株是针对S2蛋白的，SARS病毒的受体结合区正位于第310～535氨基酸这一区段。具有中和活性的McAb通过间接免疫荧光、ELISA、酶标免疫组化法和胶体金方法对SARS病毒进行检测，都显示出高度的特异性和良好亲和力。结论 成功制备了具中和活性的抗SARS-CoV单克隆抗体，并分别测定了McAb对S蛋白和N蛋白的特异抗原结合活性，初步确定了S蛋白的中和表位。为今后SARS病毒的特异诊断、结构蛋白的功能分析和重组疫苗的研制奠定了较好的基础。     

Severe acute respiratory syndrome coronavirus 2 may cause liver injury via Na+/H+ exchanger

The liver has many significant functions, such as detoxification, the urea cycle, gluconeogenesis, and protein synthesis. Systemic diseases, hypoxia, infections, drugs, and toxins can easily affect the liver, which is extremely sensitive to injury. Systemic infection of severe acute respiratory syndrome coronavirus 2 can cause liver damage. The primary regulator of intracellular p H in the liver is the Na⁺/H⁺ exchanger(NHE). Physiologically, NHE protects hepatocytes from ap...     

Heterologous viral RNA export elements improve expression of severe acute respiratory syndrome (SARS) coronavirus spike protein and protective efficacy of DNA vaccines against SARS

The SARS-CoV spike glycoprotein (S) is the main target of the protective immune response in humans and animal models of SARS. Here, we demonstrated that efficient expression of S from the wild-type spike gene in cultured cells required the use of improved plasmid vectors containing donor and acceptor splice sites, as well as heterologous viral RNA export elements, such as the CTE of Mazon-Pfizer monkey virus or the PRE of Woodchuck hepatitis virus (WPRE). The presence of both splice sites and WPRE markedly improved the immunogenicity of S-based DNA vaccines against SARS. Upon immunization of mice with low doses (2 microg) of naked DNA, only intron and WPRE-containing vectors could induce neutralizing anti-S antibodies and provide protection against challenge with SARS-CoV. Our observations are likely to be useful for the construction of plasmid and viral vectors designed for optimal expression of intronless genes derived from cytoplasmic RNA viruses.     

Severe acute respiratory syndrome coronavirus 2 RNA contamination of inanimate surfaces and virus viability in a health care emergency unit

ObjectivesTo detect possible severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RNA contamination of inanimate surfaces in areas at high risk of aerosol formation by patients with coronavirus disease 2019 (COVID-19).MethodsSampling was performed in the emergency unit and the sub-intensive care ward. SARS-CoV-2 RNA was extracted from swabbed surfaces and objects and subjected to real-time RT-PCR targeting RNA-dependent RNA polymerase and E genes. Virus isolation from positive samples was attempted in vitro on Vero E6 cells.ResultsTwenty-six samples were collected and only two were positive for low-level SARS-CoV-2 RNA, both collected on the external surface of continuous positive airway pressure helmets. All transport media were inoculated onto susceptible cells, but none induced a cytopathic effect on day 7 of culture.ConclusionsEven though daily contact with inanimate surfaces and patient fomites in contaminated areas may be a medium of infection, our data obtained in real-life conditions suggest that it might be less extensive than hitherto recognized.     

SARS尸检组织的病理变化和超微结构观察

目的 研究严重急性呼吸综合征(SARS)尸检组织的临床病理和超微结构特征。方法 对1例SARS死亡患者做即刻肺穿刺和12h后尸检,进行病理形态和超微结构的观察;用Macchiavello法做病毒包涵体染色;并对淋巴结、脾脏、结肠、小肠及骨髓组织行CD20、CD45RO(UCHL-1)、CD4、CD8、CD68、CD34免疫组织化学标记。结果 SARS肺的主要病变为急性弥漫性全小叶性间质性炎,可见肺泡腔内透明膜形成和增生及脱落的肺泡上皮,偶见胞质内病毒包涵体样结构,病毒包涵体染色阳性,肺内小血管增生、扩张,呈血管炎性改变。淋巴结、脾脏结构破坏,淋巴滤泡消失,脾小体萎缩,淋巴细胞明显减少,组织细胞增生;结肠、小肠孤立和集合淋巴结淋巴滤泡消失;骨髓增生减低,巨核细胞增多。免疫组织化学染色：淋巴结、脾脏B细胞CD20弥漫散在阳性,CD45RO(UCHL-1)散在阳性,CD4辅助T细胞显著减少,CD8毒性T细胞稍增加,CD4／CD8比例明显小于0．5。电镜观察：肺泡内的单核巨噬细胞、肺泡上皮胞质内可见病毒样颗粒,大小80～160nm,有光晕或花环状包膜。结论 肺部明显急性弥漫性全小叶性间质性炎,肺泡腔透明膜形成,肺外淋巴造血系统明显损害,尤T细胞明显;内脏器官出血、坏死和血管炎改变等为急性SARS的形态特征;肺内所见病毒样颗粒可能为新型冠状病毒,推测其为此次SARS流行的主要病原体。     

Immunization with an attenuated severe acute respiratory syndrome coronavirus deleted in E protein protects against lethal respiratory disease

The severe acute respiratory syndrome coronavirus (SARS-CoV) caused substantial morbidity and mortality in 2002-2003. Deletion of the envelope (E) protein modestly diminished virus growth in tissue culture but abrogated virulence in animals. Here, we show that immunization with rSARS-CoV-ΔE or SARS-CoV-Δ[E,6-9b] (deleted in accessory proteins (6, 7a, 7b, 8a, 8b, 9b) in addition to E) nearly completely protected BALB/c mice from fatal respiratory disease caused by mouse-adapted SARS-CoV and partly protected hACE2 Tg mice from lethal disease. hACE2 Tg mice, which express the human SARS-CoV receptor, are extremely susceptible to infection. We also show that rSARS-CoV-ΔE and rSARS-CoV-Δ[E,6-9b] induced anti-virus T cell and antibody responses. Further, the E-deleted viruses were stable after 16 blind passages through tissue culture cells, with only a single mutation in the surface glycoprotein detected. The passaged virus remained avirulent in mice. These results suggest that rSARS-CoV-ΔE is an efficacious vaccine candidate that might be useful if SARS recurred.     

严重急性呼吸综合征患者尸解肺标本的病理改变和致病机制研究

目的研究严重急性呼吸综合征（SARS）患者尸解肺标本的病理改变和致病机制。方法观察了2003年4-7月期间死于SARS的6例患者的肺标本,并采用光镜、电镜、Masson三色染色和免疫组织化学染色方法（EnVision法）进行研究。结果肺标本的病理形态改变：（1）6例的双肺均可见到弥漫性实变病灶,肺重量明显增加;（2）6例均可见到弥漫性肺泡损伤,包括透明膜形成、肺泡腔内水肿／出血、纤维素沉积和肺泡上皮细胞脱屑,AE1／AE3免疫组织化学染色显示肺泡上皮细胞的完整性明显破坏;（3）Ⅱ型肺泡上皮细胞轻度增生,有一定异型性,细胞体积增大,胞质呈双染性和颗粒状,胞质内可见小脂肪空泡聚集（5／6）;（4）6例中有5例可见巨细胞在肺泡内浸润,巨细胞大多AEl／AE3阳性（5／6）,少数CD68阳性（2／6）;（5）组织学形态和免疫组织化学染色证实肺泡腔内和肺泡间隔内有多量巨噬细胞浸润（6／6）;（6）6例中有5例可见巨噬细胞噬红细胞象;（7）6例中有5例可见肺纤维化,包括肺泡间隔和肺间质增宽（5／6）、肺泡腔内渗出物机化（6／6）和胸膜增厚（4／6）。Masson三色染色证实胶原纤维明显增生,免疫组织化学染色显示大多数为Ⅲ型胶原。光镜和免疫组织化学染色显示5例有明显的成纤维细胞／肌纤维母细胞增生灶;（8）5例可见支气管黏膜鳞状上皮化生;（9）6例患者均可见血栓;（10）2例同时合并其他感染,1例合并细菌感染,另1例合并真菌感染。此外,电镜发现在肺泡上皮细胞和肺血管内皮细胞的胞质内有冠状病毒样颗粒。结论SARS冠状病毒直接损伤肺泡上皮细胞、巨噬细胞明显浸润和成纤维细胞／肌纤维母细胞显著增生在SARS的致病机制中起重要作用。     

严重急性呼吸综合征的临床病理及发病机制研究

目的　研究严重急性呼吸综合征 (SARS)的病理学特征及临床治疗的病理学基础 ,并探讨SARS的发病机制。方法　采用光、电镜观察 ,对 2例SARS系统尸检病例和 4例多器官多部位穿刺标本进行病理学观察 ;应用免疫组化标记并分析肺组织及免疫器官中各淋巴亚群的分布及数量变化 ;核酸原位杂交结合电镜观察 ,作SARS冠状病毒 (SARS CoV)在体病原学定位及定量检测。结果　 6例SARS肺组织均呈弥漫性肺泡上皮损伤 ,2例尸检肺组织呈急性间质性炎和区域性肺水肿 ,2例尸检和1例穿刺肺组织中肺泡腔内透明膜形成 ,1例尸检和 2例穿刺肺组织呈脱屑性终末细支气管炎及肺泡炎 ,2例穿刺病例见早期肺纤维化及肺泡腔机化。SARS肺外器官 ,2例病程 <12dSARS病例免疫器官呈较广泛的出血坏死性炎 ,组织细胞及单核细胞样免疫母细胞反应性增生 ,骨髓组织内单核 粒细胞系统相对抑制 ,而 4例病程 >2 1dSRAS病例脾脏中央动脉周围T淋巴细胞增生 ,骨髓像大致正常。体内SARS CoV存在多种感染靶细胞和靶器官 ,其中肺脏为主要靶器官 ,支气管、肾、肾上腺、心肌、胃肠道、淋巴组织及睾丸等也为靶器官。肺组织内以CD8+ 细胞浸润为主 ,杂以少数CD4 + 细胞 ;淋巴结及脾脏中CD3+ 、CD4 + 、CD8+ 和CD2 0 + 淋巴细胞亚群呈不同程度减少及比例失衡 ,而     

质粒介导的RNAi抑制SARS-CoV复制和感染

目的研究RNAi作为治疗SARS-CoV感染新策略的可能性。方法选择并克隆针对SARS-CoV编码基因的共同前导序列非结构蛋白-1(Non-structureprotein1,NSP1)的siRNAs;RT-PCR和FACS法检测所选取的siRNAs对NSP1基因抑制的特异性和有效性;利用MTT法检测选取的siRNAs对病毒感染的细胞生存率的影响;空斑形成实验证实在siRNAs存在下病毒量减少情况;RT-PCR和Western-blot法进一步证实感染细胞中S和N基因在mRNA和蛋白水平的表达情况。结果结果显示重组质粒衍生的靶向SARS-CoVNSP1的siRNAs能特异地抑制靶序列表达;在体外培养的VeroE6细胞中能显著抑制SARS-CoV的复制与繁殖。感染1d后,RT-PCR和Western-blot结果显示,同对照组相比,SARS-CoV的S和N基因的mRNA和蛋白质表达均显著减少。结论NSP1序列是SARS-CoV的RNAi策略的有效靶标,这些siRNAs很可能广泛地抑制了SARS-CoV亚基因组的合成及随后的蛋白质表达。     

严重急性呼吸综合征病原体检测及临床病理学观察

目的 研究重症急性呼吸综合征(SARS)的临床病理学特点。方法 利用3例尸检材料为观察对象,全部材料经常规HE染色,肺组织部分标本经组织化学Macchiavello法(病毒包涵体染色)、网状纤维、PAS染色;免疫组织化学;超薄切片及染色;光镜及透射电镜观察。结果 3例均以高热为首发症状,继而出现进行性呼吸困难和肺部阴影;肺部病变：双肺广泛性实变;灶性出血,坏死,脱屑性肺泡炎及支气管炎,肺泡腔内充满增生脱落的肺泡上皮及渗出的蛋白、单核细胞、淋巴细胞和浆细胞,肺透明膜形成,部分肺泡腔内、渗出物机化呈肾小球样机化性肺炎改变,肺泡上皮细胞内可见病毒包涵体;免疫器官损伤：脾脏淋巴组织大片状坏死,淋巴结灶性坏死。骨髓造血组织抑制;全身小血管炎：心、肺、肝、肾、肾上腺、横纹肌间小静脉周围及血管壁水肿,灶性纤维素样坏死,单核细胞、淋巴细胞浸润,部分小静脉有血栓形成;全身中毒性改变：肺、肝、肾、心、肾上腺实质细胞变性,坏死。肺组织透射电镜观察发现群集的病毒颗粒。结论本病是一种全身多器官损伤性疾病,肺部及免疫系统是病毒主要作用的靶器官,肺部广泛性实变,大量透明膜形成,呼吸窘迫及免疫功能低下是本病死亡的主要原因。