Authentic leadership and employees' job performance: mediation effect of positive employee health

In light of global competition and the COVID-19 pandemic, organizations are encountering an increasingly challenging and unpredictable environment. Consequently, employees are experiencing heightened levels of job strain. This study aims to explore the impact of various organizational mechanisms on promoting positive employee health within the organization, ultimately affecting employees' job performance. The findings of this study indicate that authentic leadership and the absence of organizational politics are significant predictors of positive employee health. Moreover, positive employee health has a positive influence on supervisor-rated job performance through its effect on job engagement. This study serves as a valuable resource for organizations, shedding light on the fundamental factors that contribute to positive employee health. It also raises managers' awareness of the importance of nurturing and sustaining employees' emotional and physical well-being to maintain competitiveness in the market. © 2023 Antai College of Economics and Management, Shanghai Jiao Tong University.

Natural Evolution of Porcine Epidemic Diarrhea Viruses Isolated from Maternally Immunized Piglets

Simple SummaryDuring the long-term co-evolution of the virus and the host, even closely related vaccines may emerge with incomplete protective immunity due to the mutations or deletions of amino acids at specific antigenic sites. The mutation of PEDV was accelerated by the recombination of different strains and the mutation of the strains adapting to the environment. These mutations either cause immune escape from conventional vaccines or affect the virulence of the virus. Therefore, researching and developing new vaccines with cross-protection through continuous monitoring, isolation and sequencing are important to determine whether their genetic characteristics are changed and to evaluate the protective efficacy of current vaccines. The porcine epidemic diarrhea virus (PEDV) can cause severe piglet diarrhea or death in some herds. Genetic recombination and mutation facilitate the continuous evolution of the virus (PEDV), posing a great challenge for the prevention and control of porcine epidemic diarrhea (PED). Disease materials of piglets with PEDV vaccination failure in some areas of Shanxi, Henan and Hebei provinces of China were collected and examined to understand the prevalence and evolutionary characteristics of PEDV in these areas. Forty-seven suspicious disease materials from different litters on different farms were tested by multiplex PCR and screened by hematoxylin-eosin staining and immunohistochemistry. PEDV showed a positivity rate of 42.6%, infecting the small and large intestine and mesenteric lymph node tissues. The isolated strains infected Vero, PK-15 and Marc-145 multihost cells and exhibited low viral titers in all three cell types, as indicated by their growth kinetic curves. Possible putative recombination events in the isolates were identified by RDP4.0 software. Sequencing and phylogenetic analysis showed that compared with the classical vaccine strain, PEDV SX6 contains new insertion and mutations in the S region and belongs to genotype GIIa. Meanwhile, ORF3 has the complete amino acid sequence with aa80 mutated wild strains, compared to vaccine strains CV777, AJ1102, AJ1102-R and LW/L. These results will contribute to the development of new PEDV vaccines based on prevalent wild strains for the prevention and control of PED in China.

Insights into the Epidemiology, Phylodynamics, and Evolutionary Changes of Lineage GI-7 Infectious Bronchitis Virus

Infectious bronchitis virus (IBV) is distributed worldwide and causes significant losses in the poultry industry. In recent decades, lineages GI-19 and GI-7 have become the most prevalent IBV strains in China. However, the molecular evolution and phylodynamics of the lineage GI-7 IBV strains remain largely unknown. In this study, we identified 19 IBV strains from clinical samples from January 2021 to June 2022 in China, including 12 strains of GI-19, 3 strains of GI-7, and 1 strain each of GI-1, GI-9, GI-13, and GI-28. These results indicated that lineages GI-19 and GI-7 IBVs are still the most prevalent IBVs in China. Here, we investigated the evolution and transmission dynamics of lineage GI-7 IBVs. Our results revealed that the Taiwan province might be the origin of lineage GI-7 IBVs and that South China plays an important role in the spread of IBV. Furthermore, we found low codon usage bias of the S1 gene in lineage GI-7 IBVs. This allowed IBV to replicate in the host during evolution as a result of reduced competition, mainly driven by natural selection and mutational pressure, where the role of natural selection is more prominent. Collectively, our results reveal the genetic diversity and evolutionary dynamics of lineage GI-7 IBVs, which could assist in the prevention and control of viral infection.

FACTORS CONTRIBUTING TO THE NEW CORONAVIRUS INFECTION, INCREASED RISK OF COMPLICATIONS AND DEATH FROM IT IN THE ARMED FORCES OF THE RUSSIAN FEDERATION

Based on the assessment of factors that contribute to a new coronavirus infection, the risk of complications, mortality, and lethality from it in the Armed Forces of the Russian Federation were analyzed. A detailed timeline of the development of the coronavirus pandemic in the Russian Federation has been demonstrated, showing indicators of peak and overall morbidity and mortality and prevailing strains of a new coronavirus infection, depending on the waves of the pandemic. The study evaluated the features of the course of a new coronavirus infection in the Eurasian region using data from the international register "Analysis of the dynamics of comorbid diseases in patients infected with severe acute respiratory syndrome-2 coronavirus”. Modern ideas about the main pathogenetic mechanisms of involvement of the circulatory system, which underlie the development of a severe course, mortality, and lethal outcomes, are outlined. The study also presented the concept of metabolic and hemodynamic insufficiency, which justifies the inability of the desynchronized circulatory system and systems of vascular homeostasis and hemostasis to restore the previous level of functioning after a new coronavirus infection. The possibilities of carrying out differentiated anti-epidemiological measures, including the use of information technologies, aimed at reducing the spread of a new coronavirus infection, were evaluated. The mortality and mortality from a new coronavirus infection in the Armed Forces of the Russian Federation, including the effect of a new coronavirus infection on an increase in the incidence of non-communicable diseases in military personnel of different age groups, were presented. The study also considered issues of the need to introduce a rehabilitation strategy to correct conditions that occur after a new coronavirus infection, reduce the risk of subsequent mortality and lethality, and reduce it in the long term. All rights reserved © Eco-Vector, 2022.

A third dose of the BNT162b2 mRNA vaccine sufficiently improves the neutralizing activity against SARS-CoV-2 variants in liver transplant recipients.

Introduction: We examined the neutralizing antibody production efficiency of the second and third severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine doses (2nd- and 3rd-dose) and neutralizing activity on mutant strains, including, the Ancestral, Beta and Omicron strains using green fluorescent protein-carrying recombinant SARS-CoV-2, in living-donor liver transplantation (LDLT) recipients. Methods: The patients who were administered vaccines other than Pfizer- BioNTechBNT162b2 and who had coronavirus disease 2019 in this study period were excluded. We enrolled 154 LDLT recipients and 50 healthy controls. Result: The median time were 21 days (between 1st and 2nd vaccination) and 244 days (between 2nd and 3rd vaccination). The median neutralizing antibody titer after 2nd-dose was lower in LDLT recipients than in controls (0.46 vs 1.00, P<0.0001). All controls had SARS-CoV-2 neutralizing antibodies, whereas 39 LDLT recipients (25.3%) had no neutralizing antibodies after 2nd-dose; age at vaccination, presence of ascites, multiple immunosuppressive treatments, and mycophenolate mofetil treatment were significant risk factors for nonresponder. The neutralizing activities of recipient sera were approximately 3-fold and 5-fold lower than those of control sera against the Ancestral and Beta strains, respectively. The median antibody titer after 3rd-dose was not significantly different between recipients and controls (1.02 vs 1.22, p=0.0758); only 5% recipients was non-responder. The neutralizing activity after third dose to Omicron strains were enhanced and had no significant difference between two groups. Conclusion: Only the 2nd-dose was not sufficiently effective in recipients; however, 3rd-dose had sufficient neutralizing activity against the mutant strain and was as effective as that in healthy controls.

Ankle Sprains in Athletes: Current Epidemiological, Clinical and Imaging Trends.

Purpose: Ankle injuries are frequent sports injuries. Despite optimizing treatment strategies during recent years, the percentage of chronification following an ankle sprain remains high. The purpose of this review article is, to highlight current epidemiological, clinical and novel advanced cross-sectional imaging trends that may help to evaluate ankle sprain injuries. Methods: Systematic PubMed literature research. Identification and review of studies (i) analyzing and describing ankle sprain and (ii) focusing on advanced cross-sectional imaging techniques at the ankle. Results: The ankle is one of the most frequently injured body parts in sports. During the COVID-19 pandemic, there was a change in sporting behavior and sports injuries. Ankle sprains account for about 16-40% of the sports-related injuries. Novel cross-sectional imaging techniques, including Compressed Sensing MRI, 3D MRI, ankle MRI with traction or plantarflexion-supination, quantitative MRI, CT-like MRI, CT arthrography, weight-bearing cone beam CT, dual-energy CT, photon-counting CT, and projection-based metal artifact reduction CT may be introduced for detection and evaluation of specific pathologies after ankle injury. While simple ankle sprains are generally treated conservatively, unstable syndesmotic injuries may undergo stabilization using suture-button-fixation. Minced cartilage implantation is a novel cartilage repair technique for osteochondral defects at the ankle. Conclusion: Applications and advantages of different cross-sectional imaging techniques at the ankle are highlighted. In a personalized approach, optimal imaging techniques may be chosen that best detect and delineate structural ankle injuries in athletes.

Newly Characterized Porcine Epidemic Diarrhea Virus GII Subtype Strain

Diarrhea outbreaks in piglets on pig farms are commonly attributed to porcine epidemic diarrhea virus (PEDV) infection. This research analyzed the S gene prevalence variation and recombination patterns in PEDV GII strains. Throughout the previous two years, 172 clinical samples of piglet diarrhea have been collected, from which 24 PEDV isolates have been isolated. Analysis of the evolutionary relationships among all 24 S genes revealed that 21 were most closely related to strains within the GII-a subgroup. The 2 isolates grouped into one clade with the GII-b subgroup. According to the mutation analysis of the amino acids (aa) that encode the S protein, 43 of the common aa in strains of the GII subtype were found to have undergone a change in polarity or charge, and 36 of these aa had a mutation frequency of more than 90%. Three different aa mutation sites were identified as exclusive to GII-a subtype strains. The genomes of three PEDV isolates were sequenced, and the resulting range in genome length was 28,035−28,041 nt. The results of recombination analysis showed that the SD1 isolate is a novel strain recombinant from the foreign S-INDEL strain and a domestic GII subtype strain. Based on the findings, the PEDV GII-a strain has been the most circulating strain in several parts of China during the previous two years. Our study reveals for the first time the unique change of aa mutations in the S protein of the GII-a subtype strain and the new characteristics of the recombination of foreign strains and domestic GII subtype strains, indicating that it is crucial to monitor the epidemic dynamics of PEDV promptly to prevent and control the occurrence of PED effectively.

Isolation and Characterization of Porcine Sapelovirus from the PDCoV-Positive Sample and Its Molecular Epidemiology in Henan Province, China

Porcine sapelovirus (PSV) is an emerging swine enteric virus that can cause various disorders including acute diarrhea, respiratory distress, reproductive failure, and polioencephalomyelitis in pigs. In this study, we isolated a PSV strain HNHB-01 from a clinical porcine deltacoronavirus- (PDCoV-) positive intestinal content of a diarrheic piglet. PSV was first identified using the small RNA deep sequencing and assembly, and further identified by the electron microscopic observation and the immunofluorescence assay. Subsequently, this virus was serially passaged in swine testis (ST) cells, and the complete genomics of PSV HNHB-01 passage 5 (P5), P30, P60, and P100 were sequenced and analyzed. 9 nucleotide mutations and 7 amino acid changes occurred in the PSV HNHB-01 P100 strain when compared with the PSV HNHB-01 P5. Pathogenicity investigation showed that orally inoculation of PSV HNHB-01 P30 could cause obvious clinical symptoms and had broad tissue tropism in 5-day-old piglets. Epidemiological investigation revealed that PSV infections and the coinfections of diarrhea coronaviruses were highly prevalent in swine herds. The complete genomes of 8 representative PSV epidemic strains were sequenced and analyzed. Phylogenetic analysis revealed that the PSV epidemic strains were closely related to other PSV reference strains that located in the Chinese clade. Furthermore, recombination analysis revealed that the recombination events were occurred in downstream of the 2C region in our sequenced PSV HNNY-02/CHN/2018 strain. Our results provided theoretical basis for future research studies of the pathogenic mechanism, evolutionary characteristics, and the development of vaccines against PSV.

Isolation, identification, and S1 gene sequencing of two strains of Avian Infectious bronchitis virus

Objective: Epidemiology and genetic variations of the infectious bronchitis virus(IBV) in Fujian province were studied. Method: Two strains of virus isolated from the diseased chickens in Fujian in 2021 were identified by chicken embryo pathogenicity test, electron microscope observation, and RT-PCR. S1 genes of the isolates were cloned, sequenced, and analyzed using biological software. Result: The two IBV strains were code named FJ-NP01 and FJ-FZ01. The full length of S1 of FJ-NP01 was 1 629 nt encoding 543 amino acids, and that of FJ-FZ01, 1 620 nt encoding 540 amino acids. The S1 gene cleavage site of FJ-FZ01 was HRRRR, same as all reference strains of genotype I branch;while that of FJ-NP01 HRRKR differed from the reported site of IBV isolated from genotype IV but same as that of TC07-2 reference strain of genotype VI. The homology of nucleotide and amino acid between the two isolates was 83.2% and 79.6%, respectively, but merely 75.7%-76.3%and 77.1%-83.5% with the Mass-type conventional vaccines H120 and H52, respectively. Further analysis showed that FJ-NP01was from a recombination event between CK CH GD LZ12-4 and L-1148, the homology of nucleotide acid between 1438-1506 nt of FJ-NP01 with CK CH GD LZ12-4 was 97%, and 95.9% between the other nucleotide acid of S1 gene with L-1148. Conclusion: It appeared that the IBV epidemic experienced in the province was complex in nature and that the existing Mass vaccines would not provide sufficient immune protection to deter the spread.

Preparation and identification of broad-spectrum monoclonal antibodies against N protein of avian infectious bronchitis virus

[Objective] To prepare broad-spectrum monoclonal antibody against N protein of avian infectious bronchitis virus (IBV), so as to lay a foundation for identifying conservative domain epitope of N protein and establish a universal IBV detection method. [Method] N protein of GX-YL5, a representative strain of IBV dominant serotype in Guangxi, was expressed in prokaryote. BALB/c mice were immunized with the purified protein. After the serum titer of the immunized mice reached 104 or more, the splenocytes were fused with SP2/0 myeloma cells. After screening by indirect ELISA, monoclonal antibody was prepared by ascites-induced method. Western blotting, IFA and indirect ELISA were used to identify the titer, subtype, reaction specificity and cross-reaction spectrum. And the prepared monoclonal antibody was used for immunohistochemical detection. And the prepared monoclonal antibody was used to detect the IBV in the trachea and kidney tissues of SPF chickens artificially infected with 4 representative IBV variants (GX-N130048, GX-N160421, GX-QZ171023 and GX-QZ170728). [Result] The prepared monoclonal antibody N2D5 had a titer greater than 217 and its subtype was IgG2b. The Western blotting and IFA results showed that the monoclonal antibody N2D5 only reacted with IBV, and were negative with Newcastle disease virus (NDV), infectious laryngotracheitis virus (ILTV), avian metapneumovirus (aMPV), infectious bursal disease virus (IBDV), avian leukosis virus (ALV) and Marek's disease virus (MDV). Monoclonal antibody N2D5 reacted with many genotypes in China and all 7 serotypes of IBV currently prevalent in Guangxi, including commonly used standard strains, vaccine strains and field strains. Immunohistochemistry showed that the virus signals could be detected in the trachea and kidney tissues of SPF chickens at different time after artificial infection of 3 representative IBV strains from chicken and 1 isolated strain from duck, which further proved its broad spectrum. [Conclusion] The monoclonal antibody N2D5 of IBV prepared based on hybridoma technology belongs to the IgG2b subtype. It has the characteristics of high specificity, wide response spectrum and strong binding ability with IBV. It can be used as a specific diagnostic antibody for clinical diagnosis of IBV and the study of virus distribution.

Etiological identification and genetic source tracking of a cluster of cases with fever during the period of regular prevention and control of COVID-19 epidemic

Objective To identify the pathogen and track the genetic source of a cluster of cases with fever in a kindergarten in Fengtai district during the normalization of COVID-19 prevention and control in Beijing.Methods A descriptive analysis method was used to investigate this cluster of cases with fever in April 2021.Pharyngeal swabs were collected and viral nucleic acid was extracted, real-time PCR was performed to identify SARS-CoV-2 and other common respiratory virus. G gene of human metapneumovirus（hMPV） was amplified by RT-PCR and was then sequenced. BioEdit was used for G gene sequence analysis and the Neighbor-Joining model in MEGA 5. 0 software was used to construct the phylogenic tree of G gene. Results A total of 16 cases were reported in one class with the incidence of 53. 3%（16/30） during 8 days of a cluster outbreak. All pharyngeal swabs collected from 12 cases were tested SARS-CoV-2 negative, six were found to be hMPV positive by multiplex-PCR, and one was positive for both human adenovirus and hMPV. Full-length sequences of G genes were obtained from 2 strains of hMPV. Sequence analysis showed that both strains were hMPV B2 and the nucleic acid homology of G gene was 96. 73%-98. 01% with strains from Japan（LC337940, LC337935, LC1922349） in 2016 and over 98. 40%with strains from Shandong（OL625642, OL625644） in 2019, Henan MN944096 in 2019.Compared with the amino acid sequence of hMPV-B2 reference strain（AY297748）, six amino acid insertions containing EKEKEK were identified between 161-166 amino acid location and N-glycosylation of G protein analysis showed that the two strains had four N-glycosylation sites. Conclusions The leading pathogen for this cluster outbreak is found to be hMPV-B2, which are highly homologous with strains from Japan, Shandong and Henan. Therefore, a non-stop surveillance of hMPV is necessary during the normalization control and prevention period for COVID-19.

Pathogenicity analysis of one avian infectious bronchitis virus stain isolated from Shanxi

In order to perform the isolation of avian infectious bronchitis virus (IBV) and study the pathogenicity of IBV isolate, the RT-PCR was used to detect nucleic acid extracted from a clinical sample of chickens, which were suspected to be infected with infectious bronchitis virus (IBV) and provided by a farmer in Yuncheng, Shanxi province. And the sample was detected as IBV positive by RT-PCR. Then 9-11-day-old SPF chicken embryonated eggs were inoculated with the sample filtered from the grinding fluid, and the obtained allantoic fluid was blindly passed by three generations (F3) and was also tested as IBV positive;The F11 generation passaged in embryonated eggs caused typical "dwarf embryo" lesions to SPF chicken embryonated eggs, and induced the loss of cilia in tracheal rings. The results showed that an IBV strain was isolated and named as YC181031. The S1 gene amplification and sequencing analysis showed that YC181031 strain belonged to IBV GI-22 genotype, which is also nephropathogenic type IBV. Seven-day-old SPF chicks were used to test the pathogenicity of the isolate. The results showed that several clinical symptoms were showed in chicks infected with YC181031, such as breathing with difficulty, depression, excreting watery droppings and death. The mortality of infected chicks was 20%. Typical pathological changes such as enlargement of kidney and urate deposition in the kidney were observed in infected chicks. The immunohistochemical assay and viral load detection were performed for the tissue samples from infected and dead chicks. The tissue lesions and distribution of virus were observed in the kidney, trachea, lung, glandular stomach, spleen and liver samples of infected chicks. RT-PCR detection of pharyngeal anal swabs showed that the virus shedding by infected chicks could be continuously detected within 14 days of the test period;The viral loads of various tissues were detected by RT-qPCR and the results showed that the viral load from high to low was kidney, trachea, lung, stomach, spleen and liver. The viral load of kidney was significantly higher than that of other tissues (P < 0.05).In this study, the pathogenicity characteristics of GI-22 genotype strain were systematically studied for the first time, providing a reference for the prevention and treatment of the disease.

Therapeutic and Dietary Support for Gastrointestinal Tract Using Kefir as a Nutraceutical Beverage: Dairy-Milk-Based or Plant-Sourced Kefir Probiotic Products for Vegan and Lactose-Intolerant Populations

Kefir is a fermented milk beverage different in consistency and taste from other popular milk-product yogurt. Unlike yogurt prepared using lactic acid bacteria in fermentation, milk is fermented for kefir production using preculture in the form of kefir grains. Therefore, the metabolic activities of a mixed culture, including strains of bacteria and yeast, contribute to the probiotic characteristics in kefir. This article is based on the review of published studies on the functionality and nutraceutical properties of kefir. The therapeutic and dietary properties of kefir beverage and its probiotic strains have been discussed for their several health benefits. Concise selected information mostly from recent reports has been presented for two categories of kefir products: milk used for the production of dairy-based traditional kefir beverages for the lactose-tolerant population, and the plant-sourced substrates used for the production of dairy-free kefir beverages for lactose-intolerant and vegan consumers.

Epidemiology and Molecular Characterizations of Coronavirus from Companion Animals Living in Chengdu, Southwest China

The recent COVID-19 pandemic has once again caught the attention of people on the probable zoonotic transmission from animals to humans, but the role of companion animals in the coronavirus (CoV) epidemiology still remains unknown. The present study was aimed to investigate epidemiology and molecular characterizations of CoVs from companion animals in Chengdu city, Southwest China. 523 clinical samples from 393 animals were collected from one veterinary hospital between 2020 and 2021, and the presence of CoVs was detected by end-point PCR using pan-CoV assay targeting the RdRp gene. Partial and complete S genes were sequenced for further genotyping and genetic diversity analysis. A total of 162 (31.0%, 162/523) samples and 146 (37.2%, 146/393) animals were tested positive for CoVs. The positive rate in rectal swabs was higher than that in eye/nose/mouth swabs and ascitic fluid but was not statistically different between clinically healthy and diseased ones. Genotyping identified twenty-two feline enteric coronavirus (FCoV) I, four canine enteric coronavirus (CECoV) I, fourteen CECoV IIa, and one CECoV IIb, respectively. Eight complete S genes, including one canine respiratory coronavirus (CRCoV) strain, were successfully obtained. FCoV strains (F21071412 and F21061627) were more closely related to CECoV strains than CRCoV, and C21041821-2 showed potential recombination event. In addition, furin cleavage site between S1 and S2 was identified in two strains. The study supplemented epidemiological information and natural gene pool of CoVs from companion animals. Further understanding of other functional units of CoVs is needed, so as to contribute to the prevention and control of emerging infectious diseases.

Characterization and Evaluation of the Pathogenicity of a Natural Gene-Deleted Transmissible Gastroenteritis Virus in China

Porcine transmissible gastroenteritis virus is the major pathogen that causes fatal diarrhea in newborn piglets. In this study, a TGEV strain was isolated from the small intestine of diarrhea piglets in Sichuan Province, China, and designated SC2021. The complete genomic sequence of TGEV SC2021 was 28561 bp, revealing a new natural deletion TGEV strain. Based on phylogenetic analyses, TGEV SC2021 belonged to the Miller cluster and was closely related to CN strains. The newborn piglets orally challenged with TGEV SC2021 showed typical watery diarrhea. In addition, macro and micropathological changes in the lungs and intestines were observed. In conclusion, we isolated a new natural deletion virus strain and confirmed that the virus strain has high pathogenicity in newborn piglets. Moreover, macroscopic and microscopic lesions were observed in the lungs and intestines of all TGEV SC2021-infected piglets. In summary, we isolated a new natural deletion TGEV strain and demonstrated that the natural deletion strain showed high pathogenicity in newborn piglets. These data enrich the diversity of TGEV strains and help us to understand the genetic evolution and molecular pathogenesis of TGEV.

Epidemiological and etiological analysis of a case cluster caused by norovirus in a nursing home in Lanzhou

Objective: To understand the epidemiology and etiology of a cluster of cases with gastroenteritis in a nursing home in Anning district of Lanzhou, and to provide a scientific evidence for the prevention and control of norovirus diarrhea in community nursing centers. Methods: From January 28 to February 4 2021, an epidemiological investigation was conducted on all diarrhea cases, nursing staff and chefs in a nursing home in Anning district, Lanzhou city. Samples of patients' anal swabs, feces, vomitus were collected for norovirus detection by real-time fluorescent PCR. ORF1/ORF2 junction region of norovirus in some selected positive samples(Ct value 25) was sequenced. MEGA-X software was used to construct a phylogenetic tree for genetic evolution analysis using the neighboring method. Results: The first case was confirmed on January20,2021, and the number of cases peaked during January 25and 29.A total of 58 clinically diagnosed cases were reported,57were older people, with an incidence of(57/360,15.83%). Diarrhea(50/58,86.21%),vomiting(35/58,60.34%),nausea(13/58,22.41%)and abdominal pain(6/58,10.34%)were common symptoms, all cases were mild. Fifty-three asymptomatic cases were detected among chefs, housekeepers and nurses.A total of 163specimens were tested, the positive rate of norovirus GII was 49.08%(80/163). The positive rate of fecal samples collected from nurses, chefs and housekeepers was 48.62%(53/109), and was11.11%(2/18)in environmental surface swabs. The possibility of other pathogenic infections such as SARS-CoV-2was ruled out by further tests. Thirteen positive samples were selected for sequencing, and 9were successfully sequenced, they were all recombinant GII.4Sydney_2012 [P16]genotypes, forming an independent cluster, while in a large evolutionary branch with the 2020GII.10 [P16]and 2019GII.2 [P16]virus strains in Lanzhou city, showing a relative close genetic connection. Conclusions: GII .4Sydney_2012[P16]genotype of norovirus is found to be causative pathogen of this outbreak, and close contact is the main reason of the outbreak and persistence of the infection,so asymptomatic infections of norovirus play an important role in the disease spreading. Therefore, public health management in nursing homes and other centralized nursing facilities should be strengthened especially for asymptomatic workers in order to prevent virus transmission.

Epidemiological and clinical characteristics of SARS-CoV-2 Omicron variant

The COVID-19 pandemic continues to rage worldwide and the SARS-CoV-2 Omicron variant has now replaced the Delta variant as the leading epidemic strain. Omicron, as one of the SARS-COV-2 variants, incorporates the most critical mutations of the Alpha and Delta variants, and is characterized by having multiple mutation sites, high viral load, stronger infectivity and immune escape, which significantly reduced the protective effect of the vaccine. However, compared with the previous SARS-CoV-2 strains, the Omicron variant is less likely to infect lung tissue, it usually causes mild clinical symptom with reduced hospitalization rate, severe disease rate and fatality rate. Three doses of allogeneic vaccine can offer better tolerance and immunogenicity, and improve the protective effect of the vaccines. The application of small-molecule antiviral drugs and neutralizing antibodies can significantly reduce the hospitalization rate and mortality rate.In this paper, the epidemiological and characteristics of the Omicron variant were reviewed in order to provide reference for clinical diagnosis and treatment of the disease.

Genetic pattern of the COVID-19 course and reinfection

A new coronavirus infection (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) broke out at the end of 2019 in Wuhan (China). The disease has become a global pandemic and claimed more than 6 million lives after spreading rapidly around the world. Issues related to the complicated course of COVID-19 mechanisms continue to be the subject of active study. It is known that morbidity and mortality increase dramatically with increasing age and concomitant diseases, including obesity, diabetes, cancer, and cardiovascular diseases. Although most infected people recover, even young and otherwise healthy patients can get sick with this disease. In this regard, an urgent task is to search for specific genetic factors that can explain the predisposition of people to infection and the development of a severe COVID-19 form. Human genetic determinants can provide the scientific basis for disease prediction and the development of personalized therapies to counteract the epidemic. In addition, cases of repeated infection with SARS-CoV-2 are increasingly being registered, which occurs 1-6 months after initial infection on average and depends on the virus genome structure. Studies conducted on sequencing viral genomes have shown that some patients were re-infected with the same strain of coronavirus, while others were different. This, in turn, causes researchers concerns about the effectiveness of immunity after infection and vaccine reliability. The genetic characteristics of a person and a virus commonly determine the tendency for reinfection. It is difficult to determine the true COVID-19 reinfection prevalence, which is explained by the low detectability of asymptomatic reinfection and the fact that many patients with a mild course of the disease were not tested at an early stage of the pandemic. Therefore, the true prevalence of reinfection with COVID-19 does not reflect the current reality. There are many more cases of reinfection than are described in the literature. In this regard, the true contribution of a virus' genetic features to reinfection of COVID-19 can be determined only after population studies, and when developing immunization programs against a COVID-19, it is necessary to take into account the prevalence of reinfection in the population.

Sentiment Analysis of COVID-19 Vaccination in Bangla Language with Code-Mixed Text from Social Media

The vaccination program which helps avert pandemics is facing new hurdles, including the emergence of hazardous new virus strains and public distrust. Analyzing the sentiment expressed in social media interactions related to vaccines may aid the health authority in implementing public safety procedures and guide the government in developing appropriate policies. The purpose of this research is to identify the public sentiments toward the COVID-19 vaccination in Bangladesh from social media comments. Comments posted on social media platforms often mix formal and informal language known as code-mixed text and do not adhere to any particular grammatical standards. In addition, the Bangla language lacks computational models and annotated resources for sentiment analysis. To overcome this, we created CoVaxBD, a Bangla-English code-mixed and sentiment-annotated corpus of Facebook comments. This paper also proposes a model for sentiment analysis based on the multilingual BERT. It achieves a validation accuracy of around 97.3 % and a precision score of approximately 97.4%. © 2022 IEEE.

Expression of Brucella abortus Omp25 protein in Lactococcus lactis probiotic bacteria

Background and purpose: The sequence of Omp25 is conserved in all Brucella species. The high antigenicity of the product of this gene stimulates the host's immune system. Using engineered probiotic bacteria is an appropriate method for vaccine transport. The aim of this study was to express the Omp25 of the Brucella abortus pathogenic bacterium in Lactococcus lactis probiotic bacterium. Materials and methods: In this experimental study, the required vector was designed and synthesized to include the gene of interest and a signal peptide (pNZ8148-Usp45-Omp25). E. coli strain TOP10F was transformed using the pNZ8148-Usp45-Omp25 expression vector based on induction by nisin. The recombinant plasmid was extracted from the transformed bacteria using a plasmid extraction kit. The L. lactis was transformed by pNZ8148-Usp45-Omp25 vector using electroporation. Evaluation of the expression of Omp25 gene at the RNA level was assessed by reverse transcription method and confirming the presence of recombinant Omp25 protein in the engineered bacteria using SDS-PAGE method. Results: Successful expression of B. abortus Omp25 in L. lactis was verified by RT-PCR. Subsequently, the proteins were separated based on molecular weight using sodium dodecyl sulfate- polyacrylamide gel electrophoresis (SDS-PAGE). The protein expression analysis showed the expression of Omp25 as a 25 kDa extra band in transformed L. lactis compared to the L. lactis receiving the vector lacking the target gene. Conclusion: This study shows that Omp25 is expressed in L. lactis transformed via pNZ8148-Usp45-Omp25 by electroporation. Transformed L. lactis can be successfully used as a subunit oral vaccine in prevention of Brucellosis.