针对SARS-CoV2不同突变株广谱特异性中和抗体的筛选与鉴定

目的筛选对严重急性呼吸综合征冠状病毒2(SARS-CoV2)不同突变株具有广谱特异性的、高亲和性中和抗体,并进行功能验证。方法用脂质体包被的SARS-CoV2刺突蛋白(S蛋白)mRNA疫苗对Balb/c小鼠进行2次免疫,测定小鼠血清中特异性抗体含量,选取抗体含量较高的小鼠进行冲击免疫;取冲击免疫后小鼠脾细胞与骨髓瘤细胞融合,用有限稀释法和ELISA筛选出上清能特异性结合S蛋白及S蛋白受体结合域(RBD)的杂交瘤细胞克隆;纯化单克隆抗体,进行假病毒中和实验,验证抗体中和活性;并通过ELISA筛选对4种SARS-CoV2突变株的重组RBD蛋白具有广谱结合特性的单克隆抗体。结果经2次免疫,检测到高剂量组4号小鼠血清中针对S蛋白的抗体含量最高;经过冲击免疫、细胞融合后,共筛选到12株与S蛋白具有结合活性的杂交瘤细胞,其中9株特异性结合RBD蛋白;假病毒中和实验结果显示,41、46和47这3株抗体在体外有显著的中和病毒活性(P<0.05);与另2株抗体相比,46号抗体显示出与SARS-CoV24种包括Omicron在内的突变株的RBD蛋白的广谱结合活性。结论46号抗体是对SARS-CoV2四种不同突变株具有广谱特异性的中和抗体,有望进一步进行人源化改造,用于新型冠状病毒肺炎(COVID-19)的治疗。

Do UV LED Devices Immolate SARS-CoV2?

Some manufactures made UVC LED Strip as disinfection tool against SARS-CoV2. Therefore, three types of commercially UVC lights were used to evaluate their efficiency to warp bacteria and viruses. We tested three commercially available UV lights devices. They were put at 4 to 5 cm to spiked sterile Petri dishes (samples) for 10, 20, 30, and 60 seconds and compared it to control (without UV light exposure). Also, the same three UV LED devices were used on Positive SARS-CoV2 swab samples (used for the Petri dishes). Serial dilutions of the cultured microbes were used for the experiment as follows: 1/10 (high concertation), 1/100, 1/1000, 1/10,000, 1/100,000 (low concertation). All three UV LED devices (DA, DB, DC) were found to have no effects on the pathogens (Bacteria or SARS-CoV2), even to the lowest Bacteria Concentration (1/100,000), when pathogens were exposed to UV radiation for 10, 20, 30, and 60 sec at distance a 4 to 5 cm. One of the manufacturers of these UVC lights (DB) claims that the device is very effective in killing Bacteria and Virus immediately at a 99.93% killing rate (in 20 sec.). This observation was not noticed. False claims may lead to severe spread of SARS-CoV2 as customers may think that the DB was disinfecting, after short exposure, while truly having no effect.

The Null Effect of UVC Ceiling Light Exposure on SARS-CoV2

There has been some extensive research investigating the effect of Far Ultraviolet Radiation (UVC) on SARS and MARS. However, to the best of our knowledge, there have not been any detailed experiments looking at the effect of UVC on COVID-19 (now is called SARS-CoV2). Many researchers in this field believe that UVC destroys SARS-CoV2 because it warps the genetic material of the virus hurdling the viral particles from reproduction. In this paper, we report the result of our novel experiments on the effect of UVC on SARS-CoV2 using a commercially available UVC source, i.e. Krypton Disinfection lighting CM15W12V Series (wavelength of 222 nm), which is sold and marketed for the disinfection of pathogens. The experiments were extended to study the effect of UVC exposure to Bacteria and Fungus. Our experiments show that UVC has no effects on SARS-CoV2 when it is close to the SARS-CoV2 culture plate (4 - 5 cm) or at a distance (2.0 to 2.9 m), i.e. when fixed at the ceiling. This observation is important as the public seems to have the impression that commercial UVC ceiling light can kill SARS-CoV2 while this study has proven the opposite. Moreover, it shows no effect even when the UVC ceiling light is radiating on SARS-CoV2 for overnight. This proves that the intensity of the UVC from these devices is relatively low. However, the UVC light is found to be effective in destroying Bacteria and Fungus (part of pathogens), substantially, in 30 sec, and completely kills them when it’s at 2.9 m (or less) away from them and exposure for one day. This indicates that the UVC light is effective for bacteria disinfection.

Synbiotic for Prevention of SARS-Cov2 Infection in High Risk Hospital Staffs: A Randomized Controlled Trial

Introduction: COVID-19 pandemic caused by the novel coronavirus SARS-CoV-2 increasingly involves people worldwide. Probiotics can improve immune system functions via different mechanisms. We proposed that Synbiotic Lactocare? may also reduce SARS-Cov2 infection in high-risk medical staff working in COVID-19 hospital wards. Method: In a randomized, controlled trial, 60 hospital staff without any history of clinical or laboratory evidence of SARS-Cov2 infection were received either once-daily oral synbiotic capsule (Lactocare?) that contains 1 billion CFU/Cap of L. (Lactobacillus) casei, L. rhamnosus, Streptococcus thermophilus, Bifidobacterium breve, L. acidophilus, Bifidobacterium infantis, L. bulgaricus, and Fructooligosacharide (Zist Takhmir, Tehran, Iran) or placebo with the same appearance for 30 days. They were followed for two months. Result: During the two-month period of this study, SARS-COV-2 RT-PCR test results were positive in three participants (9.67%) in placebo group compared to zero positive tests in synbiotic group. The differences were not statistically significant (p = 0.238). During the study, two persons (7 %) of placebo group had respiratory complaints such as cough, rhinorrhea and/or dyspnea, compared with one in synbiotic group (p = 0.492). Conclusion: This study showed that overall frequency of SARS-COV2 infection in participants receiving synbiotic and those receiving placebo did not differ significantly. However, 3 hospital staff in placebo group compared to no one in synbiotic group had SARS-COV2 infection. Further studies with greater power and alternative probiotic strains and mixture are warranted to determine whether Synbiotic can prevent COVID-19 in at-risk hospital staff.

A puzzling case of differentiation syndrome mimicking SARS-CoV2 pneumonitis: a case report

Differentiation syndrome is a complication commonly encountered in acute promyelocytic leukemia patients when treated with Al-Trans retinoic acid.This Differentiation syndrome has veryclose similarities clinically and radiologically to SARS-CoV2 pneumonitis which makes diagnosis of differentiation syndrome challenging specially during this COVID-19 pandemic.We hereby report a case of a 68-year-old male with acute promyelocytic leukemia who on initiation of Al-Trans retinoic acid developed acute respiratory distress with radiological findings of multiple ground glass opacities in bilateral lungs suggestive of SARS-CoV2 pneumonitis.Considering the radiological similarities to differentiation syndrome and on high clinical suspicion,this patient was immediately started on steroids with which he recovered rapidly.During this pandemic of SARS-CoV2,distinguishing differentiation syndrome from SARS-CoV2 pneumonitis clinically and radiologically is extremely challenging.

Humoral Response and Tolerance of Vaccination against SARS-CoV-2 in Adults Senegalese Patients Undergoing Hemodialysis: A Multicenter Prospective Study

Introduction: Following the COVID-19 pandemic, vaccination has been proposed in several countries as the main preventive measure despite very limited data, particularly in dialysis patients. We conducted this study to assess the immunological response to vaccination in Senegalese hemodialysis patients. Patients and Methods: We conducted a prospective study, in two dialysis centers in Dakar from March 30th to August 30th, 2021 including patients on hemodialysis for >6 months, vaccinated against SARS-CoV-2 according to the vaccination schedule recommended by WHO. A vaccine response was considered positive when seroconversion was observed after one dose of vaccine. The clinical efficacy of immunization was defined as the absence of new COVID-19 infection in patients who received a complete vaccination. Results: Among the 81 patients included in the study, 7.4% had anti-Spike IgM antibodies before their first vaccination. Seroprevalence of IgM antibodies was 38.3% one month after the first vaccine dose (at M1) and 8.6% one month after the second dose (at M4). Anti-Spike IgG antibodies were present in 40.3% of patients before vaccination, in 90.1% at M1, and in 59.7% at M4. Among patients previously infected with SARS-CoV-2, 10.2% had IgM antibodies at M0, 31.6% at M1, and 10.5% at M4 post-vaccination. Similarly, seroprevalences of IgG antibodies in this subgroup were 31.5%, 61.3%, and 50.0% respectively at M0, M1, and M4 post-vaccination. A comparison of seroconversion rates between M0 and M4 showed significant differences only for IgG in COVID-19 naive patients. Mean duration in dialysis and the existence of previous COVID-19 infection were associated with patients’ vaccinal response after the two doses. Age, gender and the use of immunosuppressive treatment did not influence post-vaccinal antibody production. Conclusion: Vaccination against COVID-19 in Senegalese hemodialysis patients induced a low seroconversion rate but it was well tolerated. Moreover, the induced protection was neither strong nor durable, particularly in patients with longer duration in dialysis.

Updated thoughts on SARS-CoV-2 and coronavirus therapies,fighting and surviving

From late December 2019 a new human-adapted coronavirus,SARS-CoV-2,was observed and isolated in clustered patients in Wuhan,China.It has been proved to be able to transmit human-to-human and cause pneumonia,leading to about 2%fatality.Its genome characteristics,immune responses and related potential treatments,such as chemical drugs,serum transfusion and vaccines including DNA vaccines,are discussed in this review for a brief summary.

抗SARS-CoV免疫球蛋白F(ab′)_2治疗性抗体对SARS-CoVBJ-01株的中和作用

目的观察马抗SARS-CoV免疫球蛋白F(ab′)2治疗性抗体对SARS-CoVBJ-01毒株的中和作用。方法采用细胞病变法(cytopathiceffect,CPE)、四甲基偶氮唑盐(methylthiazolyltetrazoliumassay,MTT)测定马抗SARS-CoV免疫球蛋白F(ab′)2对SARS-CoVBJ-01株的中和作用。结果三批马抗SARS-CoV免疫球蛋白F(ab′)2对SARS-CoVBJ-01株有很好的中和作用,CPE和MTT法测得中和效价分别为1∶6400、1∶6400、1∶12800。结论研制的马抗SARS-CoV免疫球蛋白F(ab′)2对SARS-CoVBJ-01株有很好的中和作用,并且两种方法结果一致,为SARS的治疗提供了可靠的依据。

SARS-CoV、MERS-CoV、SARS-CoV-2的基因结构特点与致病机制

高致病性冠状病毒具有高发病率、高病死率以及全球大流行等特点,严重威胁人类健康,给社会经济带来巨大挑战。目前关于高致病冠状病毒的致病机制,主要从直接细胞病变效应和间接免疫病理损伤两方面进行讨论,但具体作用基因的研究尚需进一步深入。本文从高致病性冠状病毒的基因结构特点与致病机制的相关性进行综述,为预防和治疗高致病性冠状病毒感染提供参考。

Heart Failure in Children in a Context of Sars-Cov 2 Infection: About Two Cases at the University Hospital Center of Libreville, Gabon

This study reports two observations of heart failure diagnosed in the context of SARS-CoV 2 infection in children at the University Hospital Center of Libreville, Gabon. Long considered exempted from serious forms of Covid-19 infection, the fatal evolution of one of the two cases proves that there is an interest for a more rigorous approach in their management in a pandemic context. The multisystem inflammatory syndrome associated with this virus in children can be responsible for cardiac manifestations that can be life-threatening. Early diagnosis and treatment are necessary to reduce mortality. However, this approach is made difficult in our regions by the limited biomedical equipment and the absence of essential therapies as noted in these two observations.

马抗SARS-CoV免疫球蛋白对SARS-CoV GZ-01株中和作用的研究

观察马抗SARS-CoV免疫球蛋白对SARS-CoV GZ-01毒株的中和作用,为马抗SARS-CoV免疫球蛋白用于SARS的治疗提供科学的依据。采用CPE、MTT测定马抗SARS-CoV免疫球蛋白对SARS-CoV GZ-01株的中和作用。结果显示,马抗SARS-CoV免疫球蛋白F(ab’)2治疗性抗体对SARS-CoV GZ-01株具有很好的中和作用,三批马抗SARS-CoV免疫球蛋白的CPE和MTT中和效价分别达到1:6400、1:6400、1:12800,且两种方法测得结果一致。

Epidemiological, Clinical, Therapeutic, Evolutionary and Prognostic Aspects of Children with COVID-19 in Bouaké(Côte d’Ivoire)

Context: Compared to adults, there are relatively few studies on pediatric COVID-19 due to the high rate of asymptomatic or paucisymptomatic forms. The aim of this study is to determine the epidemiological, clinical, therapeutic, evolutionary and prognostic aspects of COVID-19 infection in children. Patients and Methods: This was a prospective analytical study carried out from February 27, 2021 to January 27, 2022 at the COVID-19 Care Center of the Infectious and Tropical Diseases Department of the Bouaké University Teaching Hospital. The study population consisted of all children under the age of 16, seen in consultation and/or hospitalized with a positive COVID-19 RT-PCR. Data analysis was performed with Epi Info 7 software. The statistical tests used were the chi-square test and Fisher’s exact test depending on the conditions of validity with a significance threshold of p Results: Out of 955 patients received at the COVID-19 Care Center in Bouaké, there were 56 children (26 boys/30 girls), or, a prevalence of 5.86%. The mean age was 9.18 years ± 4.48 [extremes 3 months and 15 years]. Children over the age of 11 accounted for 48.21% of cases. They were contact cases in 35.71% and the contact person was the mother in 75% of cases. The main reasons for screening were cough (67.86%), fever (25%) and sneezing (21.43%). The pathological histories were asthma (83.33%), heart disease (33.33%) and sickle cell disease (16.67%). The medical examination revealed 6 cases of children in vital distress. The care consisted of home confinement for simple cases (89.29%) and hospitalization for cases presenting with vital distress (10.71%). The duration of confinement or hospitalization was between 10 and 15 days in 83.93% of cases. No cases of death were noted. The factors associated with the occurrence of symptomatic forms were age (p = 0.028), pathological history (p Conclusion: The proportion of pediatric cases of COVID-19 is low with a predominance during the season of harmattan. Pediatric infection with COVID-19 is benign and has a favorable evolution, with an almost intra-family transmission wich symptomatology is different from that of adults. Age and pathological history were the factors associated with the occurrence of symptomatic forms.

COVID-19 in Bouake (Côte D’Ivoire): Comparative Study of the Epidemiological, Clinical, Therapeutic, Evolutionary and Prognostic Aspects in Younger and Elderly Patients

Introduction: The clinical manifestations of many diseases vary with age, and older people often do not show typical symptoms of the disease. The present study aims to compare the epidemiological, clinical, therapeutic and evolutionary aspects of elderly patients with COVID-19 compared to young adult patients and to identify risk factors for mortality. Patients and Methods: This was a retrospective single-center analytical study conducted from January 27, 2021 to January 27, 2022 at the COVID-19 Care Center of the Infectious and Tropical Diseases Department of the Bouaké University Teaching Hospital. The study population consisted of all patients aged at least 18 years seen in consultation and/or hospitalized with a positive COVID-19 RT-PCR. The patients were divided into two groups: younger patients (Results: Of a total of 779 patients, 644 (82.7%) were young. The median age of all patients was 41 years (IQR 32 - 54, extreme 18 and 96). Of all the patients 38.5% had a comorbidity. Compared to younger patients, chronic heart disease (61.7% vs 21.5%;p Conclusion: Elderly people with COVID-19 have a different clinical presentation from younger, characterized by more atypical symptoms. Mortality risk factors are age, dyspnoea, impaired consciousness and fever. It is therefore necessary to act on its various factors to improve the prognosis of COVID-19 in this age group.

Towards an Artificial Intelligence Framework for Data-Driven Prediction of Coronavirus Clinical Severity

The virus SARS-CoV2,which causes the Coronavirus disease COVID-19 has become a pandemic and has spread to every inhabited continent.Given the increasing caseload,there is an urgent need to augment clinical skills in order to identify from among the many mild cases the few that will progress to critical illness.We present a first step towards building an artificial intelligence(AI)framework,with predictive analytics(PA)capabilities applied to real patient data,to provide rapid clinical decision-making support.COVID-19 has presented a pressing need as a)clinicians are still developing clinical acumen given the disease’s novelty,and b)resource limitations in a rapidly expanding pandemic require difficult decisions relating to resource allocation.The objectives of this research are:(1)to algorithmically identify the combinations of clinical characteristics of COVID-19 that predict outcomes,and(2)to develop a tool with AI capabilities that will predict patients at risk for more severe illness on initial presentation.The predictive models learn from historical data to help predict specifically who will develop acute respiratory distress syndrome(ARDS),a severe outcome in COVID-19.Our experimental results based on two hospitals in Wenzhou,Zhejang,China identify features most predictive of ARDS in COVID-19 initial presentation which would not have stood out to clinicians.A mild increase in elevated alanine aminotransferase(ALT)(a liver enzyme)),a presence of myalgias(body aches),and an increase in hemoglobin,in this order,are the clinical features,on presentation,that are the most predictive.Those two centers’COVID-19 case series symptoms on initial presentation can help predict severe outcomes.Predictive models that learned from historical data of patients from two Chinese hospitals achieved 70%to 80%accuracy in predicting severe cases.

COVID-19 compared to other epidemic coronavirus diseases and theflu

Coronaviruses are among the largest group of known positive-sense RNA viruses with a wide range of animal hosts as reservoir. In the last two decades,newly evolved coronaviruses such as the severe acute respiratory syndrome coronavirus(SARS-CoV) which caused the infamous 2002 outbreak, the Middle East respiratory syndrome coronavirus(MERS-CoV) which caused an outbreak in 2012, and now the SARS-CoV-2 [responsible for the current coronavirus disease 2019(COVID-19)] have all posed notable threats to global public health.But, how does the current COVID-19 outbreak compare with previous coronaviruses diseases? In this review, we look at the key differences between SARS-CoV, MERS-CoV, and SARS-CoV-2, and examine challenges in determining accurate estimates of the severity of COVID-19. We discuss coronavirus outbreaks in light of key outbreak severity indicators including,disease fatality, pathogen novelty, ease of transmission, geographical range, and outbreak preparedness. Finally, we review clinical trials of emerging treatment modalities and provide recommendations on the control of COVID-19 based on the mode of transmission of the coronaviruses. We also recommend the development and use of a standardized predictive epidemic severity models to inform future epidemic response.

Epidemiology of COVID-19 in Misrata, Libya: A Population-Based Surveillance Study

Background: The prevalence of SARS-COV2 in Libya is unclear;PCR is still under-performed. Although lockdown measures have been in place for weeks, there is no prevalence data to support the gradual lifting of such lockdowns. SARS-COV2 IgM/IgG is emerging as potential alternatives to PCR testing, and many counties and towns have undertaken such seroprevalence studies. Objective: Prevalence of SARS-COV2 in Misrata, Libya amongst the population as a whole. Materials and Methods: The study was prospective, cross-sectional, population-based, and age-stratified, to assess SARS-COV2 IgM/IgG in the population of Misrata. It was carried out between the 18th and 21st of April, 2020. Results: A representative sample of 897 participants was tested for SARS-COV2 IgM/IgG antibodies. 30 participants were positive for IgM or IgG indicating a prevalence of 3.4% (95% CI, 2.8% - 5.2%), with eight (0.9%) IgM positive and 22 (2.4%) IgG positive. Accordingly, 9075 (95% CI, 6586 - 14,170) people are estimated to have had a current or recent COVID-19 infection, symptomatic or asymptomatic. Conclusion and Recommendations: Serological testing as a diagnostic or surveillance tool may uncover a large proportion of asymptomatic individuals in the community, far outnumbering PCR. The authors highly recommend further precautionary public measures, as well as an ongoing surveillance programme to monitor the epidemiological trends of the disease in the city of Misrata and Libya in general.

Semantic Pneumonia Segmentation and Classification for Covid-19 Using Deep Learning Network

Early detection of the Covid-19 disease is essential due to its higher rate of infection affecting tens of millions of people,and its high number of deaths also by 7%.For that purpose,a proposed model of several stages was developed.The first stage is optimizing the images using dynamic adaptive histogram equalization,performing a semantic segmentation using DeepLabv3Plus,then augmenting the data by flipping it horizontally,rotating it,then flipping it vertically.The second stage builds a custom convolutional neural network model using several pre-trained ImageNet.Finally,the model compares the pre-trained data to the new output,while repeatedly trimming the best-performing models to reduce complexity and improve memory efficiency.Several experiments were done using different techniques and parameters.Accordingly,the proposed model achieved an average accuracy of 99.6%and an area under the curve of 0.996 in the Covid-19 detection.This paper will discuss how to train a customized intelligent convolutional neural network using various parameters on a set of chest X-rays with an accuracy of 99.6%.

COVID-19 Related Multisystem Inflammatory Syndrome in Children: A Case Series from a Tertiary Hospital in Riyadh, Saudi Arabia

Introduction: We report an eight-case series of coronavirus disease 2019 (COVID-19)-related multisystem inflammatory syndrome in children (MIS-C). Methods: Children who tested positive for COVID-19, met the MIS-C criteria of the World Health Organization (WHO), and were <span style="font-family: ">hospitalized at a tertiary hospital in Riyadh from September to December 2021 were identified and their clinical data reviewed. Results: The age at diagnosis is <span style="font-family: ">between 4 to 13 years old. Fever, decreased oral intake, gastroenteritis, and abdominal pain were the most common symptoms. All cases showed hyperinflammation with high C-reactive protein, erythrocyte sedimentation rate, ferritin levels, and deranged coagulation profiles. Most of the cases had elevated B-type natriuretic peptide (75%) and troponin (100%) levels. However, two cases had cardiovascular involvement. Two patients presented with acute respiratory distress syndrome and required mechanical ventilation. The mean hospital stay was 13.1 days, with seven patients initially requiring intensive care management for ionotropic support. Most cases required broad-spectrum antibiotics, intravenous steroids, intravenous immunoglobulin, and aspirin. All patients recovered and were discharged from the hospital in good clinical condition. Conclusion: Children with COVID-19 are at risk of developing MIS-C. Practitioners must have a high index of suspicion for its diagnosis and should start treatment as soon as possible to prevent unfavorable outcomes.

Post-COVID-19 Late Pulmonary Embolism in a Young Woman about a Case

COVID-19 appears to be associated with a disproportionate risk of thrombosis. The occurrence of thrombosis is a frequent complication of many medical and surgical conditions. Their prevention by LMWH is the option of choice as well as their early diagnosis in this pandemic context. In addition, several recent observations support that severe pulmonary embolism is very common in hospitalized patients with COVID-19. We report the case of late pulmonary embolism in a 26-year-old patient with a medical history of (SARS-CoV2) and newly discovered diabetes. The clinical examination found exertional dyspnea, intense chest pain, blood pressure at 145/85mmHg, heart rate at 129 bpm, respiratory rate at 25 cycles/min, blood sugar at 1.45 g/l, oxygen saturation at 92%. In front of this clinical picture, the thoracic CT angiography to ask shows a pulmonary embolism of the right segmental and sub-segmental branches less marked on the left, involving the lingular and basal branches; the management was limited to anticoagulation associated with rehabilitation sessions (respiratory physiotherapy).

Vaccines’ Safety and Effectiveness in the Midst of Covid-19 Mutations

We examined the coronavirus classification and evolution through its multiple mutations that have increased its transmissibility rate up to 70% globally, threatening to undermine the promise of a number of emerging vaccines that primarily focus on the immune detection of the Spike trimer. The safety and effectiveness of different vaccination methods are evaluated and compared, including the mRNA version, the Adenovirus DNA, Spike protein subunits, the deactivated virus genres, and the live attenuated coronavirus. Mutations have been long considered as random events, or mistakes during the viral RNA replication. Usually, what can go wrong will go wrong;therefore, repeated transformations lead to the extinction of a virus. On the contrary, the aggregate result of over 300,000 Covid-19 variants has expanded its transmissibility and infectiousness. Covid-19 mutations do not degrade the virus;they empower and facilitate its disguise to evade detection. Unlike other coronaviruses, Covid-19 amino acid switches do not reflect the random unfolding of errors that eventually eradicate the virus. Covid-19 appears to use mutations adaptively in the service of its survival and expansion. We cite evidence that Covid-19 inhibits the interferon type I production, compromising adaptive immunity from recognizing the virus. The deleterious consequences of the cytokine storm where the CD8+ killer cells injure the vital organs of the host may well be a Covid-19 manoeuvring to escape exposure. It is probable that evolution has programmed Covid-19 with an adeptness designed to debilitate key systemic defences to secure its subsistence. To date the infectiousness of the Covid-19 pandemic is exponentially increasing, denoting the possibility of an even more dangerously elusive, inconspicuous, and sophisticated version of the disease.