北京SARS疫情走势的模型分析与预测

北京SARS疫情的公布数据表明，4月下旬以来，确诊病例的相对增加率随累计确诊病例数的增加而下降．假设这是一个线性关系，并且一直持续下去，我们发现疫情走势是一个反转的Fermi-Dirac分布，根据现有的公布数据可以预期北京平均每日新增病例数将在5月中旬下降到50人以下，在5月下旬下降到10人以下，在6月上旬下降到1人左右，疫情可望在6月中得到控制，最后的累计病例总数约为3千人左右。     

新型全新风"免疫"空调系统的初步研究

提出了一种新型的,基于高效换热和间接蒸发冷却的全新风免疫空调系统,从理论和热力计算等方面对全新风系统和回风系统做了比较。初步研究结果表明,该新型全新风系统不但可以从根本上改善室内空气品质,而且其能量消耗水平与现有回风空调系统相接近,具有良好的研究开发前景。     

Study of new protective clothing against SARS using semi-permeable PTFE/PU membrane

Chemicals which may pose a hazard to people upon contact may be in several forms, such as liquid, mist, vapor, etc. The damage caused can range from mild skin diseases to more serious chronic illnesses. Therefore, chemical protective clothing must be used to safe some personal who may be exposed to hazardous chemicals. The use of PTFE/PU membrane for chemical protective clothing is discussed in the article. By means of texturing with organic conductive fiber, and then treating with JAM-Y1 anti-bacteria agent, in the end, treating with the XL-550 waterproof agent, the PET fabric has permanent anti-static, anti-bacteria and waterproof and anti-oil properties. The PTFE/PU protective material is prepared by laminating with PET fabric by paste dot coating, and then coated by PU solution in a direct process. The PU coating agent, DMF and acetone, are used in testing through surface tension and peeling strength measurement. The penetration property of poliomyelitis virus in liquid and animalcule in air of PTFE membrane laminated textile, after being coated by PU solution are measured. The results show that it can separate SARS virus in air and liquid, and WVT is 11496 g/24 h m². Then it can provide a satisfactory wearing comfort.     

The Two-Way Switch Role of ACE2 in the Treatment of Novel Coronavirus Pneumonia and Underlying Comorbidities

December 2019 saw the emergence of the coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), which has spread across the globe. The high infectivity and ongoing mortality of SARS-CoV-2 emphasize the demand of drug discovery. Angiotensin-converting enzyme II (ACE2) is the functional receptor for SARS-CoV-2 entry into host cells. ACE2 exists as a membrane-bound protein on major viral target pulmonary epithelial cells, and its peptidase domain (PD) interacts SARS-CoV-2 spike protein with higher affinity. Therefore, targeting ACE2 is an important pharmacological intervention for a SARS-CoV-2 infection. In this review, we described the two-way switch role of ACE2 in the treatment of novel coronavirus pneumonia and underlying comorbidities, and discussed the potential effect of the ACE inhibitor and angiotensin receptor blocker on a hypertension patient with the SARS-CoV-2 infection. In addition, we analyzed the S-protein-binding site on ACE2 and suggested that blocking hot spot-31 and hot spot-353 on ACE2 could be a therapeutic strategy for preventing the spread of SARS-CoV-2. Besides, the recombinant ACE2 protein could be another potential treatment option for SARS-CoV-2 induced acute severe lung failure. This review could provide beneficial information for the development of anti-SARS-CoV-2 agents via targeting ACE2 and the clinical usage of renin-angiotensin system (RAS) drugs for novel coronavirus pneumonia treatment.     

Computational simulation of interactions between SARS coronavirus spike mutants and host species-specific receptors

As a critical adaptive mechanism, amino acid replacements on the severe acute respiratory syndrome coronavirus (SARS-CoV) spike protein could alter the receptor-binding specificity of this envelope glycoprotein and in turn lead to the emergence or reemergence of this viral zoonosis. Based on the X-ray structures of SARS-CoV spike receptor-binding domain (RBD) in complex with its functional receptor (angiotensin-converting enzyme 2, ACE2), we perform computational simulations of interactions between three representative RBD mutants and four host species-specific receptors. The comparisons between computational predictions and experimental evidences validate our structural bioinformatics approaches. And the predictions further indicate that some viral prototypes might utilize the rat ACE2 while rats might serve as a vector or reservoir of SARS-CoV.     

催化材料对病毒吸附及灭活作用特性的研究

以核酸分子及普通病毒作为探针和模拟对象,进行了催化材料吸附 灭活副流感病毒的研究,旨在筛选出对病毒有过滤 吸附及灭活作用的高效非特异性催化材料,以应用于病毒的各种防护设施以及有效控制非典型性肺炎的传播。共评价了93种新合成的催化剂,发现两种催化材料对病毒具有杀灭作用。     

SARS 3CL蛋白酶同源二聚化与底物结合互为别构调控因素

研究了严重急性呼吸系统综合症(SARS)冠状病毒3C-Like蛋白酶(3CLpro)在存在底物或抑制剂时的二聚体形成情况. 通过测定酶活性随酶浓度的变化, 拟合出在底物存在下酶二聚体的解离常数约为0.94 μmol·L-1, 小于纯蛋白酶的二聚体解离常数(14.0 μmol·L-1), 表明底物对二聚体的形成具有增强作用. 选用与底物具有类似结合方式的靛红类抑制剂N-萘甲基靛红-5-甲酰胺(5f), 利用超速离心沉降速率方法定量测定了SARS 3CL蛋白酶单体和二聚体在不同浓度5f时的含量, 发现5f同样具有诱导二聚体形成的能力. 在3 μmol·L-1蛋白酶浓度下测定得到诱导二聚的EC50 值(半数有效浓度)约为1 μmol·L-1, 说明二聚体中只有一个单体与抑制剂结合. 研究结果表明, 随着底物浓度的升高, SARS 3CL蛋白酶会形成更多的二聚体, 而二聚体含量的提高又反过来提高酶的活性, 这种双向别构调控机制有可能是病毒用来调控多聚蛋白水解速率和组装时机的一种方法.     

洁净室空调系统与传染性隔离病房的设计探讨

本文对洁净室空调系统及传染性隔离病房空调系统的设计特点以及在温湿度控制,气流控制,气压控制,节能措施等方面进行了总结与叙述。     

Improving control effects of absence seizures using single-pulse alternately resetting stimulation(SARS) of corticothalamic circuit

Presently, we develop a simplified corticothalamic(SCT) model and propose a single-pulse alternately resetting stimulation(SARS) with sequentially applying anodic(A, "+") or cathodic(C, "-") phase pulses to the thalamic reticular(RE) nuclei,thalamus-cortex(TC) relay nuclei, and cortical excitatory(EX) neurons, respectively.Abatement effects of ACC-SARS of RE, TC, and EX for the 2 Hz–4 Hz spike and wave discharges(SWD) of absence seizures are then concerned. The m∶n on-off ACC-SARS protocol is sh...     

Synthesis and Biological Evaluation of Quinolinone Compounds as SARS CoV 3CL^pro Inhibitors

SARS CoV 3CL^pro is known to be a promising target for development of therapeutic agents against the severe acute respiratory syndrome （SARS）. A quinolinone compound 1 was selected via virtual screening, and it was syn- thetized and tested for enzymatic inhibition in vitro. Compound 1 showed potent inhibitory activity （ICs0= 0.44 μmol/L） toward SARS CoV 3CL^pro. Further work on a series of quinolinone derivatives resulted in the discovery of the most potent compound 23, inhibiting SARS CoV 3CL^pro with an IC50 of 36.86 μmol/L. The structure-activity relationships were also discussed.