Compatibility Theory of Yiqi Zengmian Prescription as Vaccine Adjuvant / 中国实验方剂学杂志

ObjectiveThis study explored the application of Yiqi Zengmian prescription as a vaccine adjuvant， aiming to provide a new scheme for the prevention and control of corona virus disease 2019（COVID-19） with traditional Chinese medicine （TCM）. By analyzing the compatibility and efficacy， this paper examines the compatibility effect of Yiqi Zengmian prescription， which is modified from the classic tonifying agent Si Junzitang， as a vaccine adjuvant. MethodUsing the Database of Ancient Classical Prescriptions， this paper analyzed the composition of Yiqi Zengmian prescription and probed into the theoretical basis for the compatibility of this prescription from the properties， medicine combination， and efficacy. Furthermore， the compatibility effect of this prescription with vaccines was analyzed. ResultAs a TCM prescription， Yiqi Zengmian prescription focuses on the lung and spleen and enhances the Qi in the two organs. The lung governs Qi movement. The body breathes fresh air through the lungs and exchanges the turbid gas in the lungs， and the gas circulates alternately in the lungs to ensure the normal breathing of the human body. The spleen governing transportation and transformation is the hub for Qi movement， and Qi is the embodiment of metabolic function. By regulating qi movement and enhancing the functions of Qi and blood， Yiqi Zengmian prescription can enhance the immunogenicity of the vaccine， which provides a theoretical basis for enhancing the immune effects of vaccines. ConclusionYiqi Zengmian prescription has the effects of replenishing Qi and invigorating spleen， regulating Qi and drying dampness， and enhancing immunity. The in-depth analysis of the TCM theory of Yiqi Zengmian prescription as a vaccine adjuvant and the results of clinical and laboratory studies suggest that Yiqi Zengmian prescription may enhance the induction of immune response after vaccination and maintain the immune memory. However， the mechanism of Yiqi Zengmian prescription in regulating the complex immune network remains to be elucidated.

The impact of SARS-CoV-2 infection on term placentae

Background: Coronavirus 2019 infection (COVID 19) is an ongoing pandemic caused by pathogenic RNA viruses called severe acute respiratory syndrome coronavirus-2 (SARS-COV-2). It has affected people of all ages, with high morbidity and mortality among the elderly and immunocompromised population. Limited information is available on the effects of COVID-19 infection on pregnancy. Aim: To describe the histopathological changes in the placental tissue of SARS-CoV-2 infected term mothers with no comorbidities and to correlate with neonatal outcome. Materials and Methods: This observational study was conducted in the Department of Pathology, KMCH institute of health sciences and research, Coimbatore from May 1, 2020 to November 30, 2020 for 6 months. Placental tissues of all COVID-19-positive term mothers with no comorbidities were included in this study. Histopathological examination of placentae was carried out and clinical data of mothers and newborn babies were obtained from medical records. Results: Histopathological examination of 64 placental tissue of COVID-19 mothers showed predominantly the features of fetal vascular malperfusion like stem villi vasculature thrombus, villous congestion, and avascular villi. No significant correlation was obtained in comparison with parity and symptomatic status of the mothers. However, histopathological changes were more prominent among symptomatic patients. The newborn babies born to these mothers showed no adverse outcome. Conclusion: This study concluded that though COVID-19 infection in normal term pregnant women was associated with increased prevalence of features of fetal vascular malperfusion, there was no significant morbidity in the health status of both COVID-19 mothers and their neonates.

Bi-directional screening for COVID-19, tuberculosis and diabetes in flu, DOTS and NCD clinics in a rural hospital in Northern India

Introduction: To assess the status of bi-directional screening for COVID-19, tuberculosis and diabetes among people attending Non-communicable Disease (NCD), Directly Observed Treatment Short-course (DOTS), and flu clinics of a secondary care hospital in rural northern India. Material and Methods: A cross?sectional, analytical study was conducted among the eligible (aged ?18 years) population who attended the study clinics in a rural sub-district hospital. In the flu clinic, consecutive patients were assessed for screening for TB (symptom-based) and diabetes (random blood sugar) and status of referral to DOTS and NCD clinics. Similarly, the screening for diabetes and COVID-19, Reverse Transcription-Polymerase Chain Reaction (RT-PCR) in the DOTS clinic, and TB and COVID-19 in the NCD clinic were assessed. The independent association of factors with COVID-19 positivity were assessed by calculating the adjusted prevalence ratios (aPR) at 95% confidence interval (CI). Results: Of the 405 people assessed, 279 (68.9%), 102 (25.2%), and 24 (5.9%) were from flu, NCD, and DOTS clinics, respectively. 26 (25.5%) and 22 (91.7%) of NCD and DOTS clinic patients underwent RT-PCR for COVID-19. TB screening in NCD and flu clinics was done among 4 (3.9%) and 7 (12.5%), respectively. A total of 23 (9.0%) were found positive for COVID-19, and no factors other than the presence of COVID-19 symptoms (aPR: 2.89; 95% CI: 1.33–6.29) had any independent association with COVID-19 positive status. Conclusion: The low screening for TB in NCD and flu clinics indicates the need to strengthen the implementation the TB-DM and TB-COVID-19 bidirectional screening. Similarly, the low screening or testing for COVID-19 in the NCD clinic can be improved by the implementation of systematic screening strategies like TB-DM bidirectional screening.

A study of outcome in COVID-19 patients receiving casirivimab-imdevimab

Objectives: In December 2019, coronavirus disease 2019 (COVID-19) was first identified in Wuhan, China, as a respiratory tract infection causing symptoms, such as fever, chills, dry cough, fatigue, and shortness of breath. Despite the low mortality rate of COVID-19, patients with comorbidities such as hypertension, cardiovascular disease, and diabetes mellitus seem to be prone to more severe symptoms and to a higher mortality rate than others. Such patients are shown to benefit from usage of monoclonal antibodies. Casirivimab-imdevimab is a cocktail made up of two non-competing, neutralizing human immunoglobulin G1 antibodies that target the receptor binding domain of the severe acute respiratory syndrome coronavirus 2 spike protein and block viral entry into human cells. We assessed the clinical profile and outcome of 42 patients who received the antibody cocktail. Materials and Methods: Casirivimab-imdevimab was administered to COVID-positive patients with mild severity. Forty-two patients who satisfied the inclusion criteria received casirivimab-imdevimab and were included in the study. Demographic and clinical data were tabulated in Microsoft Excel and statistics were run in OpenEpi software. Results: No adverse reactions were seen in any of the patients. Among the 42 patients, there were no deaths. Twentytwo (52.3%) patients improved, while 20 (47.6%) worsened after receiving the antibody cocktail. Out of 21 (50%) patients who did not have any comorbidity, 13 (30.9%) worsened after receiving the drug and 8 (19%) improved, while among those with comorbidities, 7 (16.6%) worsened and 14 (33.3%) improved (P < 0.05). Thirteen (30.9%) unvaccinated patients improved, while 14 (33.3%) worsened, whereas 6 (14.2%) fully vaccinated patients improved while only 2 (4.7%) worsened. Among the patients who were administered the cocktail within 5 days of onset of symptoms, 12 (28.5%) improved and 10 (23.8%) worsened, whereas among those who received the drug between 6 and 10 days of symptom onset, ten improved, and ten worsened. There was no statistically significant association between vaccination status and outcome, and infusion interval and outcome in these patients. Conclusion: None of the 42 patients developed any reaction to casirivimab-imdevimab. There were no deaths in the study population. About 52.3% of the patients improved and 47.6% worsened after receiving the cocktail. About 33.3% of the comorbid patients improved. There was no statistically significant association between vaccination status and outcome, and infusion interval and outcome in these patients.

Molecular aspects of COVID-19 and its relationship with obesity and physical activity: a narrative review

Abstract BACKGROUND: Severe acute respiratory syndrome coronavirus 2 has several mechanisms of action related to inflammatory responses, especially in individuals diagnosed with obesity. This hyperinflammatory clinical profile resulting from the association between obesity and coronavirus disease 2019 (COVID-19) may be attenuated by regular physical activity. OBJECTIVE: The aim of this study was to review the evidence on the consequences of physical inactivity and physical activity on COVID-19 in patients with obesity. DESIGN AND SETTING: Narrative review at the Bahiana School of Medicine and Public Health in Salvador, Brazil. METHODS: We searched evidence on the association of COVID-19 with physical activity and obesity using the following keywords: "covid-19," "physical activity," and "obesity". The databases used were MEDLINE (PubMed), ScienceDirect, and Virtual Health Library. Studies published from 2019 to 2021 and available in Portuguese, English, and Spanish were included. The final search was conducted on September 26, 2021. RESULTS: We identified 661 studies in the database, among which 71 were considered for inclusion in the narrative review of the molecular aspects of COVID-19 and its relationship with physical activity and obesity. CONCLUSION: This literature review enabled the perception of the relationship between the molecular mechanisms of COVID-19 and obesity. Regular physical activity had various benefits for the inflammatory condition of the studied population, highlighting moderate-intensity.

Serosurvey for SARS-CoV-2 among blood donors in Wuhan, China from September to December 2019

The emerging of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused COVID-19 pandemic. The first case of COVID-19 was reported at early December in 2019 in Wuhan City, China. To examine specific antibodies against SARS-CoV-2 in biological samples before December 2019 would give clues when the epidemic of SARS-CoV-2 might start to circulate in populations. We obtained all 88,517 plasmas from 76,844 blood donors in Wuhan between 1 September and 31 December 2019. We first evaluated the pan-immunoglobin (pan-Ig) against SARS-CoV-2 in 43,850 samples from 32,484 blood donors with suitable sample quality and enough volume. Two hundred and sixty-four samples from 213 donors were pan-Ig reactive, then further tested IgG and IgM, and validated by neutralizing antibodies against SARS-CoV-2. Two hundred and thirteen samples (from 175 donors) were only pan-Ig reactive, 8 (from 4 donors) were pan-Ig and IgG reactive, and 43 (from 34 donors) were pan-Ig and IgM reactive. Microneutralization assay showed all negative results. In addition, 213 screened reactive donors were analyzed and did not show obviously temporal or regional tendency, but the distribution of age showed a difference compared with all tested donors. Then we reviewed SARS-CoV-2 antibody results from these donors who donated several times from September 2019 to June 2020, partly tested in a previous published study, no one was found a significant increase in S/CO of antibodies against SARS-CoV-2. Our findings showed no SARS-CoV-2-specific antibodies existing among blood donors in Wuhan, China before 2020, indicating no evidence of transmission of COVID-19 before December 2019 in Wuhan, China.

Clinical characteristics of severe acute respiratory syndrome coronavirus 2 vaccine breakthrough infections in children / 中华传染病杂志

Objective:To analyze the clinical characteristics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine breakthrough infections in children, and to provide reference basis for the SARS-CoV-2 vaccination in children.Methods:A total of 97 children aged 3 to 14 years and diagnosed with coronavirus disease 2019 (COVID-19) admitted to Xi′an People′s Hospital (Xi′an Fourth Hospital) from December 27, 2021 to February 7, 2022 were included. According to the COVID-19 vaccination status, the enrolled children were divided into unvaccinated group, partially vaccinated group and fully vaccinated group, and the clinical data of the children in the three groups were collected and compared. Chi-square test, two independent sample t-test and Kruskal-Wallis H test were used for statistical analysis. Results:Totally 97 children including 49 males and 48 females were enrolled, with 87(89.7%) children of mild type, 10(10.3%) children of common type, and no severe or critical case. The proportions of unvaccinated, partially vaccinated and fully vaccinated preschool-aged children (3 to 6 years old) were 56.5%(13/23), 30.8%(12/39) and 17.1%(6/35), respectively, while those of school-aged children (7 to 14 years old) were 43.5%(10/23), 69.2%(27/39) and 82.9%(29/35), respectively. The vaccination proportion in preschool-aged children was significantly lower than that in school-age children ( χ2=9.94, P=0.007). The proportion of the children with fever in fully vaccinated group was 17.1%(6/35), which was lower than that in unvaccinated group (43.5%, 10/23), and the difference was statistically significant ( χ2=4.82, P=0.028). The cycle threshold (Ct) values of the open reading frame ( ORF)1 ab gene in the unvaccinated, partially vaccinated and fully vaccinated groups were 33.77(26.87, 36.58), 35.23 (33.45, 38.57) and 37.12 (34.91, 39.39), respectively, and there was a statistically significant difference among the groups ( H=7.76, P=0.021). The Ct values of the nucleocapsid protein ( N) gene in the three groups were 32.26(25.85, 36.18), 35.12(33.18, 37.96) and 37.26(34.27, 39.24), respectively, and the difference among the groups was statistically significant ( H=7.84, P=0.020). The Ct values of ORF1 ab gene and N gene in fully vaccinated group were higher than those in unvaccinated group, and the differences were statistically significant ( Z=-2.69, P=0.007 and Z=-2.39, P=0.017, respectively). The duration of viral shedding in fully vaccinated children was (9.9±4.1) d, which was shorter than that in unvaccinated children ((12.8±3.7) d), and the difference was statistically significant ( t=2.72, P=0.009). Conclusions:The majority of children with breakthrough infections with SARS-CoV-2 are mild. Vaccination may effectively shorten the duration of viral shedding. And fully vaccination is associated with mild clinical symptoms and lower serum viral load compared to unvaccinated children.

False positive reaction of COVID-19 antibody ELISA screening: internal logic of various methods / 中国输血杂志

【Objective】 To analyze the results of different methods for reactive samples screened by the enzyme linked immunosorbent assay (ELISA) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in blood donors. 【Methods】 From March to April 2020, a total of 8 632 blood samples in Shenzhen were screened for SARS-CoV-2 total antibodies (TAb, including IgG, IgM, IgA) in plasma using ELISA(PC group), the antibody reactivity samples and their follow up plasma samples (FC group), and samples of disease control group(DC group) from January to April 2020 were detected using the following methods: 1) ELISA method for detecting IgG, IgM, and (or without detection) TAb; 2) pseudovirus neutralizing antibody test(pVNT); 3) western blot (WB) of SARS-CoV-2 antibody. The negative control group(NC group) from February to April 2020 performed ELISA and WB testing. 【Results】 Among the 34 total antibody positive samples, 2 were positive for pVNT test, and the total antibody, IgG and WB in the initial screening and tracking testing were positive. Thereafter, it was determined to be confirmed positive. The other 2 cases were positive for pVNT test, while the samples with positive WB results were in the follow-up stage. The TAb, IgG, and pVNT results did not conform to the dynamic evolution of antibodies, and cannot be determined as confirmed positive. 【Conclusion】 The infection status of antibody reactivity samples screened by SARS-CoV-2 ELISA can be judged by the logic of pVNT, WB and the dynamic change of antibody.

Expression optimization and preliminary identification of recombinant monoclonal antibody IgA against SARS-CoV-2 / 中国生物制品学杂志

@#Objective To prepare monoclonal antibody IgA against severe acute respiratory syndrome coronavirus 2(SARSCoV-2),optimize relevant expression conditions to increase the expression level,and preliminarily explore the effect of IgA antibody on anti-SARS-CoV-2.Methods The plasmid encoding IgAl-F61 antibody sequence was mixed with polyethyleneimine(PEI) transfection reagent and then transfected into EXPi293F~(TM) cells to transiently express antibody protein;The optimal culture conditions and expression levels of monomeric IgAl(mIgAl)-F61 and dimeric IgAl(dIgAl)-F61 in EXPi293F~(TM) cells were determined by optimizing the ratio of heavy chain(Hc),light chain(Lc) and joining chain(Jc),the proportion of plasmid and PEI,and the harvest time after transfection.The supernatant after transfection was purified by affinity chromatography,and then determined for the concentration by BCA,analyzed for the expression integrity and purity of antibody by SDS-PAGE and size exclusion chromatography-high performance liquid chromatography(SEC-HPLC),and detected for the neutralizing activity of antibody by pseudovirus neutralization assay.Results The optimal expression level of mIgAl-F61 was 123.45 μg/mL and the purity of purified antibody was over 95% when the ratio of Hc to Lc was 1:2,the ratio of plasmid to PEI was 1:3,and the supernatant was harvested 5 d after transfection;The highest purity of dIgAlF61 was more than 90% when the ratio of Hc:Lc:Jc was 1:2:1.The results of pseudovirus neutrali-zation assay against Omicron BA.4/5 showed that dIgAl-F61 exhibited better neutralizing activity than IgG-F61,and the value of half maximum inhibitory concentration(IC_(50)) was reduced by about 4 times.Conclusion Recombinant monoclonal antibodies mIgAl-F61 and dIgAl-F61 against SARS-CoV-2 were successfully expressed with high purity and dIgAl showed better neutralizing activity than IgG in vitro.

Expression optimization and preliminary identification of recombinant monoclonal antibody IgA against SARS-CoV-2 / 中国生物制品学杂志

@#Objective To prepare monoclonal antibody IgA against severe acute respiratory syndrome coronavirus 2(SARSCoV-2),optimize relevant expression conditions to increase the expression level,and preliminarily explore the effect of IgA antibody on anti-SARS-CoV-2.Methods The plasmid encoding IgAl-F61 antibody sequence was mixed with polyethyleneimine(PEI) transfection reagent and then transfected into EXPi293F~(TM) cells to transiently express antibody protein;The optimal culture conditions and expression levels of monomeric IgAl(mIgAl)-F61 and dimeric IgAl(dIgAl)-F61 in EXPi293F~(TM) cells were determined by optimizing the ratio of heavy chain(Hc),light chain(Lc) and joining chain(Jc),the proportion of plasmid and PEI,and the harvest time after transfection.The supernatant after transfection was purified by affinity chromatography,and then determined for the concentration by BCA,analyzed for the expression integrity and purity of antibody by SDS-PAGE and size exclusion chromatography-high performance liquid chromatography(SEC-HPLC),and detected for the neutralizing activity of antibody by pseudovirus neutralization assay.Results The optimal expression level of mIgAl-F61 was 123.45 μg/mL and the purity of purified antibody was over 95% when the ratio of Hc to Lc was 1:2,the ratio of plasmid to PEI was 1:3,and the supernatant was harvested 5 d after transfection;The highest purity of dIgAlF61 was more than 90% when the ratio of Hc:Lc:Jc was 1:2:1.The results of pseudovirus neutrali-zation assay against Omicron BA.4/5 showed that dIgAl-F61 exhibited better neutralizing activity than IgG-F61,and the value of half maximum inhibitory concentration(IC_(50)) was reduced by about 4 times.Conclusion Recombinant monoclonal antibodies mIgAl-F61 and dIgAl-F61 against SARS-CoV-2 were successfully expressed with high purity and dIgAl showed better neutralizing activity than IgG in vitro.

Research progress of angiotensin converting enzyme 2 co-expression in non-small cell lung cancer and SARS-CoV-2 / 中国胸心血管外科临床杂志

@#Since the first case of corona virus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the end of 2019, the virus has spread rapidly around the world and has become a global public health problem. In the process of this virus epidemic, compared with the general population, cancer patients are considered to be highly susceptible people, especially the lung cancer patients. Some studies have shown that angiotensin converting enzyme 2 (ACE2) may be the pathway for SARS-CoV-2 to infect the host. At the same time, ACE2 is often abnormally expressed in non-small cell lung cancer. Therefore, understanding the respective mechanisms of ACE2 in COVID-19 and non-small cell lung cancer has extremely important reference value for the study of vaccines and therapeutic drugs, and also provides meaningful guidance for the protection of patients with lung cancer during the epidemic. This article reviews the possible invasive mechanism of ACE2 in SARS-CoV-2 and its abnormal expression in non-small cell lung cancer.

Characteristics of digestive system symptoms and abdominal computed tomography imaging of patients infected with severe acute respiratory syndrome coronavirus 2 Omicron variant / 中华消化杂志

Objective:To investigate the characteristics of digestive system symptoms and its relation with the time of nucleic acid continuous positive in population infected with severe acute respiratory syndrome coronavirus 2 Omicron variant, and to analyze the abdominal computed tomography (CT) features of patients infected with Omicron variant.Methods:From April 11 to May 23, 2022, a questionnaire survey was conducted in patients infected with Omicron variant admitted to the Shanghai National Convention and Exhibition Center Fangcang Hospital. The questionnaire included basic information, the start time of nucleic acid positive, respiratory symptoms, digestive system syptoms and outcomes, etc.Combined with the clinical data, the relation between digestive tract symptoms and the time of nucleic acid continuous positive were analyzed. Thoracic and abdominal CT were performed for patients with continuous positive nucleic acid results ≥10 d, and the relationship between the abdominal CT imaging characteristics and the time of nucleic acid continuous positive was analyzed. Independent sample t-test and multivariate logistic regression were used for statistical analysis. Results:A total of 4 360 valid questionnaires were collected, including 2 475 males and 1 885 females, with a hospital stay of (6.8±4.9) d. Among the 4 360 patients, 1 979 patients (45.4%) had gastrointestinal symptoms such as loss of appetite, abdominal discomfort or pain, constipation and diarrhea. The time of nucleic acid continuous positive in patients with gastrointestinal symptoms was (7.4±5.5) d, which was longer than that of patients without gastrointestinal symptoms (6.5±3.6) d, and the difference was statistically significant ( t=3.78, P<0.001). During the isolation period in the Fangcang Hospital, the time of nucleic acid continuous positive in patients with complete remission of digestive tract symptoms was shorter than that of patients with no remission of digestive tract symptoms ((7.3±5.2) d vs. (8.5±5.7) d), and the difference was statistically significant ( t=2.25, P=0.025). The results of multivariate logistic regression analysis showed that the combination of gastrointestinal symptoms was an independent risk factor for continuous positive nucleic acid result ≥10 d ( OR=1.316, 95% confidence interval 1.294 to 2.205, P=0.046). Among the 299 patients with continuous positive nucleic acid results≥10 d, 187 cases (62.5%) had gastrointestinal symptoms, and 146 cases (48.8%) had abdominal CT findings of thickening of the gastroduodenal wall, thickening of the small intestinal wall, indistinct mesenteric vessels of the small intestine, and dilatation and pneumatosis of the colon. In patients with continuous positive nucleic acid results ≥10 d, abdominal CT indicated that patients with gastrointestinal imaging changes had a longer time of nucleic acid continuous positive than those without gastrointestinal imaging changes ((16.0±2.8) d vs. (13.0±2.1) d), and the difference was statistically significant ( t=2.62, P=0.009). Conclusions:Digestive system symptoms are common in patients infected with Omicron variant. The time of nucleic acid continuous positive in patients with gastrointestinal symptoms is longer than those without gastrointestinal symptoms. Some patients may have gastrointestinal lesions on abdominal CT.

Clinical characteristics, treatment and vaccination effect of SARS-CoV-2 Omicron variant infection in kidney transplant recipients abroad / 中华器官移植杂志

The Omicron variant of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is highly contagious, but compared to early virus typing has milder symptoms and better prognosis.This article reviewed and analyzed the clinical characteristics, treatment, prognosis and vaccination effect of Omicron infection in Kidney transplant recipients (KTR) in recent years.The clinical manifestations of KTR infected with Omicron and the comparison with early variants, the clinical characteristics of KTR infected with Omicron compared with the general population, the treatment of KTR infected with Omicron after foreign countries, the effect of vaccination on KTR to prevent Omicron and the measures to increase the ted of vaccine, the summary of the prevention and treatment of KTR infected with Omicron abroad and the experience and the shortcomings of the current researches were analyzed and summarized.

Research progress of m 6A methylation modification in respiratory viruses replication and host immune response / 中华临床感染病杂志

N 6-methyladenosine (m 6A) modification is the most prevalent internal modification of eukaryotic mRNA and is dynamically regulated by a variety of m 6A modifying enzymes, including methylation transferases, demethylases and specific binding proteins. Respiratory viral infections have received much attention in recent years, and the process of virus replication and metabolism in host cells is regulated by m 6A. This article reviews the mechanism of m 6A-regulated enzymes, the roles of m 6A modifications in respiratory viruses replication and the host immune response to viruses, including adenovirus, influenza A virus, severe acute respiratory syndrome coronavirus 2, respiratory syncytial virus, and human metapneumovirus. It would provide a reference for exploring the regulatory role of viral episodic transcriptome modifications and antiviral targets or vaccine development.

Clinical features of acute macular neuroretinopathy induced by Omicron / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To observe the clinical features of acute macular neuroretinopathy(AMN)induced by Omicron.METHODS: A retrospective study. A total of 9 patients(18 eyes)diagnosed with AMN from December 2022 to January 2023 in the Hospital of Chengdu University of Traditional Chinese Medicine were included. Patients underwent spectral-domain optical coherence tomography(SD-OCT), fundus fluorescein angiography(FFA), fundus photography, autofluorescence(AF), infrared reflectance(IR), optical coherence tomography angiography(OCTA)and multicolor, etc. Furthermore, they were followed up for 1～3mo and observed the prognosis.RESULTS: The initial symptom of the Omicron-induced AMN was the sudden onset of central/paracentral scotoma in the eyes with or without impaired vision and metamorphopsia, and the scotoma could persist for at least 3mo. The image features of AMN are as follows. First, the SD-OCT examination showed the rupture of outer retinal layers, scattered hyperreflective lesions, and atrophy of outer retinal layers. In severe cases, hyperreflective lesions were seen in the inner nuclear layer(INL)or with microcystic cavities under the retinal pigment epithelium(RPE). Second, the OCTA examination demonstrated the decreased blood flow density of the deep capillary plexus(DCP)of the macula. Third, the IR examination showed the weak reflection of lesion areas. Fourth, the fundus photography demonstrated the localized brown wedge-shaped lesion.CONCLUSIONS: The Omicron-induced AMN is mostly found in young females, and the characteristic manifestation of fundus is damage to the outer retinal layers. The extent of fundus lesions is related to the systemic inflammatory response and ocular microcirculatory changes after infection. The multimodal fundus image examination and a history of Omicron infection are helpful to diagnose the Omicron-induced AMN.

Characteristics of viral shedding in people infected with SARS-CoV-2 during difference stages / 中国热带医学

@#Abstract: Viral shedding of SARS-CoV-2 is a continuous dynamic process, which can be divided into latent stage, initial stage, peak stage and decreasing stage according to the characteristics of viral shedding. After being infected with SARS-CoV-2, the infected person generally stays in the latent period for 1-3 days, which is characterized by continuous negative nucleic acid test results and no infectiousness, and the risk of infection for close contacts is very low. At the initial stage of viral shedding is characterized by a rapid decline in the Ct value of nucleic acid tests in a short time, and clinical symptoms gradually appear. The infectiousness of the infected person gradually increases during this period, and the risk of infection for close contacts also gradually increases, but it is still in the early stage of infection, the possibility of viral shedding is low, and the risk of infection of secondary close contacts is low. The peak of viral shedding is characterized by low Ct value in nucleic acid test and obvious clinical symptoms; during this period, the infected person is the most infectious, and the risk of infection of the contact is the highest, so the scope of close contacts should be expanded appropriately. The decreasing period is characterized by the gradual increase of Ct value of nucleic acid test and the gradual disappearance of clinical symptoms; during this period, the infectiousness of the infected person gradually decreases to disappear. In an outbreak, an infected person in the decreasing phase is more likely to be an early infected person in the transmission chain. If infected individuals in the decreasing phase are found in an area without a SARS-CoV-2 epidemic, it suggests that the local outbreak epidemic has been spreading for some time and may be larger in scale. According to the characteristics of viral shedding, risk personnel can be determined more scientifically and accurately, so as to minimize the risk and reduce the waste of epidemic prevention resources.

Analysis of clinical characteristics and warning factors in SARS-CoV-2 variants infection / 中国热带医学

@#Abstract: Objective To investigate the influence of the variation of SARS-CoV-2 on the clinical feature, and to provide early warning signs for the variation of SARS-CoV-2 in clinical work. Methods From Jan 2, 2021 to Jun 30, 2021, a total of 105 COVID-19 patients were included in the study using a case-control method. Nasal swab samples were collected from the study subjects, the viral genes were sequenced, and patients were divided into Delta variant group and non-Delta variant group according to their gene sequences. Clinically relevant data were collected from the two groups, and indicators such as days of hospitalization, age distribution, lymphocytes, neutrophils, B lymphocytes, NK cells, IL-4, and IL-10 were compared; subgroup analysis was performed based on the number of days of viral negativity in the study subjects as the basis for grouping, and differences in immunological characteristics were compared, including lymphocytes, neutrophils, B lymphocytes, NK cells, IL-4, IL-10, etc. Results The theoretical hospitalization days of Delta variant group were (22.2±8.33) d, which were significantly longer than (17.6±10.50) d of non-Delta variant group (t=2.396, P<0.05). The total lymphocyte count and IL-4 of Delta variant group were (1.22±0.86) ×109/L and (0.80±0.23) ng/mL, which were significantly lower than corresponding (1.91±0.70) ×109/L and (1.59±0.59) ng/mL of non-Delta variant group (t=4.329, 9.072, P<0.05), while IL-10 was (7.16±7.77) ng/mL, which was significantly higher than (4.26±3.91) ng/mL of non-Delta mutation group (t=1.980, P<0.05). Subgroup analysis showed that the total lymphocyte count and IL-4 concentration in Delta variant group were (1.04±0.60) ×109/L and (0.74±0.25) ng/ml, which were significantly lower than corresponding (1.62±0.56) ×109/L and (1.56±0.52) ng/mL in non-Delta variant group, in patients with delayed discharge (P<0.05). Conclutions SARS-CoV-2 variant has an impact on clinical manifestations. The patient's B cell count and IL-10 concentration increased or IL-2 and IL-4 concentration decreased within 12 hours of admission indicated variant virus infection. The decrease of total lymphocyte count, especially T lymphocyte reduction, strongly suggests discharge delay due to viral clearance disorder.

Clinical research progress on drugs against SARS-CoV-2 / 中国生物制品学杂志

@#The rapid spread of Coronavirus Disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection has had a devastating impact on public health and the global economy. Tremendous efforts had been put on urgent development of prophylactic or therapeutic drugs against SARS-CoV-2,mainly smallmolecule antiviral drugs and monoclonal antibodies,to reduce the impact and burden of COVID-19. Currently,National Medical Products Administration(NMPA)of China or Food and Drug Administration(FDA)of the United States have approved three small-molecule drugs and three monoclonal antibodies for use. This paper reviews the clinical research progress and challenges of the main drugs against SARS-CoV-2 on the market at present.

Development of uniform antigen content detection kit for recombinant SARS-CoV-2 protein vaccines / 中国生物制品学杂志

@#Objective To prepare and verify a uniform antigen content detection kit for recombinant protein vaccines against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2). Methods Using goat anti-S protein polyclonal antibody prepared by National Institutes for Food and Drug Control(NIFDC) as coating antibody,one of four monoclonal antibodies(14C8,15F9,17A7 and 20D8)with high receptor-binding domain(RBD)binding activity and broad-spectrum resistance against major variants as HRP-labeled antibody,a uniform double-antibody sandwich ELISA kit for antigen content detection of recombinant SARS-CoV-2 vaccine was prepared,and the dilution of coating antibody(1∶125 ～ 1∶4 000)and enzymelabeled antibody(1∶250 ～ 1∶32 000)were optimized by chessboard titration. The specificity,linear range,accuracy,precision and durability of the kit were verified. The prepared uniform detection kits were distributed to 12 laboratories to detect15 batches of recombinant SARS-CoV-2 protein vaccine stock solutions(including 11 batches of stock solutions designed with WT strain and 4 batches of designed with Beta,Gamma and Delta variants as reference sequence)from different expression systems(CHO cells,Pichia pastoris,Sf9 cells or E. coli)and target proteins(RBD or S protein)prepared by each laboratory.Results Monoclonal antibody 20D8 was used as the enzyme-labeled antibody with the optimal dilution of 1 : 4 000,and the optimal dilution of coating antibody was 1 : 500. The uniform detection kit showed no cross reaction with recombinant S protein of severe acute respiratory syndrome(SARS)and Middle East respiratory syndrome(MERS). The first generation national standard for recombinant SARS-CoV-2 protein vaccine antigen(national standard for short)showed a concentration of 0. 16 ～ 2. 50 U/mL with a good linear relationship with A450/630,and the linear equation was:y = 0. 791 x-0. 100 4,R2= 0. 993 7;The recoveries of 0. 16 ～ 2. 50 U/mL national standard in 6 repeated tests were 95% ～ 104% and the coefficients of variation(CVs)were less than 15%;The CVs in 3 repeated tests by 2 experimenters at different time were 4. 4% ～6. 6% and the recoveries were in the range of 80% ～ 120% under different temperature and time conditions. The antigen content of 15 batches of recombinant SARS-CoV-2 protein vaccine stock solutions showed good parallelism with the national standard. Conclusion The uniform detection kit for antigen content developed in this study had good specificity,accuracy,precision and durability,and might be used for the detection of antigen content of recombinant SARS-CoV-2 protein vaccines.

Screening and identification of single-chain fragment variable against the receptor-binding domain of spike protein of SARS-CoV-2 / 中国生物制品学杂志

@#Objective To construct a single-chain fragment variable(scFv)phage display library against receptor-binding domain(RBD)of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)spike protein(S)to screen specific scFv and identify the function.Methods m RNA was extracted from spleen cells of mice immunized with RBD protein and reversely transcribed into c DNA,with which as template,genes of the hight chain fragment of variable(VH)and light chain fragment of variable(VL)of scFv were amplified and then assembled into scFv gene fragment through splicing overlap extension PCR(SOE-PCR).The scFv gene fragment was inserted to phage vector to construct scFv phage display library.After four rounds of biopanning,the scFv gene with strong binding ability to RBD was screened and expressed recombinantly,purified and identified for biological activity.Results The constructed scFv phage library showed a titer of 6.0×10(11)pfu/m L.After four rounds of biopanning,four scFv strains with strong binding to RBD were selected,namely scFv11,scFv12,scFv25and scFv28.scFv was mainly expressed in the form of inclusion body with a relative molecular mass of about 27 000,a concentration of 2.4 mg/m L and a purity of about 90%,which bound specifically to mouse monoclonal antibody against His labeled by HRP after purification.All four scFv strains bound specifically to RBD recombinant protein,among which the other 3 scFv strains bound to the S protein of wild type and multiple mutant strains except scFv28.All four strains showed dose-dependent interaction with RBD,with affinity dynamic fitting dissociation constants(K_Ds)8.9,5.92,10.67and 2.36 nmol/L,and steady-state fitting dissociation constants(K_Ds)of 5.3,6.5,8.7 and 5.8 nmol/L,respectively.scFv11,scFv12 and scFv25 simultaneously identified three independent RBD polypeptides,including RBD2(S(11)pfu/m L.After four rounds of biopanning,four scFv strains with strong binding to RBD were selected,namely scFv11,scFv12,scFv25and scFv28.scFv was mainly expressed in the form of inclusion body with a relative molecular mass of about 27 000,a concentration of 2.4 mg/m L and a purity of about 90%,which bound specifically to mouse monoclonal antibody against His labeled by HRP after purification.All four scFv strains bound specifically to RBD recombinant protein,among which the other 3 scFv strains bound to the S protein of wild type and multiple mutant strains except scFv28.All four strains showed dose-dependent interaction with RBD,with affinity dynamic fitting dissociation constants(K_Ds)8.9,5.92,10.67and 2.36 nmol/L,and steady-state fitting dissociation constants(K_Ds)of 5.3,6.5,8.7 and 5.8 nmol/L,respectively.scFv11,scFv12 and scFv25 simultaneously identified three independent RBD polypeptides,including RBD2(S(334～353)),RBD9(S(334～353)),RBD9(S(439～458))and RBD13(S(439～458))and RBD13(S(499～518)).Homologous model of scFv constructed by online server SWISS-MODEL showed a good quality and was used for molecular docking.The interface at which scFv11 interacted with RBD only partially coincided with the interaction interface of human angiotensin converting enzyme 2(ACE2)and RBD,and the interaction interfaces of scFv12 and scFv25 with RBD were quite different from that of ACE2.Conclusion In this study,scFv specifically bound to SARS-Co V-2 RBD was screened and prepared through constructing scFv phage library against SARS-CoV-2 RBD,which provided experimental basis for further development of anti-SARS-CoV-2 drugs and detection reagents.