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Objective To investigate the impact of the outbreak of coronavirus disease 2019 (COVID-19) as an intervention factor on residency training at different stages, and look into the enhancement effect of post-graduation medical training program based on competency of residency training, so as to provide reference for the optimization of medical education at the postgraduate stage. Methods After the initial success of COVID-19 prevention and control, 169 clinical postdoctoral trainess(clinical postdocs) and 515 graduate students specializing in clinical medicine(professional postdocs) were surveyed by an anonymous online questionnaire. To analyze the differences of cognition and self- evaluation of core competence between the two groups. Results There were 141 valid questionnaires collected from clinical postdocs (83.43%, 141/169) and 264 valid questionnaires collected from professional postdocs (51.26%, 264/515). In both groups, more than 85% of the students agreed or strongly agreed that they had a deeper understanding of the profession of doctors during the epidemic. The results of competency self-evaluation showed that, except for the items of "self-improvement", the self-evaluation scores of clinical postdoctoral students on other items were significantly higher than those of professional postdoctoral students (all P <0.05). Conclusions COVID-19, as a factor of emergency intervention, can improve the competency cognition of residents. The core-competency based post-graduation medical education model can comprehensively improve the students' comprehensive ability, which is an effective training program for residents. It is suggested that the vocational planning education for residents should be paid attention to in the stage of college education, and a new mode of college education that is closely combined with the post-graduation education should be further explored.Copyright © 2021 Thomson Reuters and Contributors.
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COVID-19 is the most widespread infectious disease in the world. There is an incubation period in the early stage of infection. At present, there are some difficulties in the diagnosis of COVID-19. Medical image analysis based on computed tomography (CT) images is an important tool for clinical diagnosis. However, the lesion size of COVID-19 is smaller, and the lesion shape of COVID-19 is more complex. The effect of the aided diagnosis model is not good. To solve this problem, an aided diagnostic model of COVID-ResNet was proposed based on CT images. Firstly, an improved attention ResNet model was designed based on CT images to focus on the focal lesion area. Secondly, the SE-Res block was constructed. The squeeze excitation mechanism with the residual connection was introduced into the ResNet. The SE-Res block can enhance the correlation degree among different channels and improve the overall accuracy of the model. Thirdly, MFCA (multi-layer feature converge attention) blocks were proposed, which extract multi-layer features. In this model, coordinated attention was used to focus on the direction information of the lesion area. Different layer features were concatenated so that the shallow layer and deep layer features were fused. The experimental results showed that the model could significantly improve the recognition accuracy of COVID-19. Compared with similar models, COVID-ResNet has better performance. On the COVID-19 CT dataset, the accuracy, recall rate, F1 score, and AUC value could reach 96.89%, 98.15%,96.96%, and 99.04%, respectively. Compared with the ResNet model, the accuracy, recall rate, F1 score, and AUC value were higher by 3.1%, 2.46%, 3.0%, and 1.16%, respectively. In ablation experiments, the experimental results showed that the SE-Res block and MFCA model proposed by us were effective. COVID-ResNet transfers the shallow features to the deep, gathers the features, and makes the information complementary. COVID-ResNet can improve the work efficiency of doctors and reduce the misdiagnosis rate. It has a positive significance for the computer-aided diagnosis of COVID-19. © 2023 by the authors.
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Objective To analyze the potential factors influencing the viral shedding time (duration of nucleic acid positivity) in elderly patients with mild and asymptomatic infection. Methods The clinical data of 1141 elderly (>=60 years) patients with mild and asymptomatic Omicron infection who were admitted to National Exhibition and Convention Center (Shanghai) Cabin Hospital from April 14, 2022 to May 1, 2022 were retrospectively collected, viral shedding time of patients were compared between different groups (age, gender, number of vaccination, hypertension, diabetes). Pearson analysis was adopted to analyze the relationship between age and viral shedding time. Kaplan-Meier curve and Log-rank test were used to evaluate the viral shedding time in elderly patients with different clinical characteristics. Multivariate Cox proportional-hazards regression model was adopted to analyze the factors influencing viral shedding time in elderly patients with Omicron. Results Among 1441 patients, 791(54.9%) males and 650(45.1%) females. There were 513(35.6%) patients receiving 0 dose of vaccine, 29(2.0%) patients received 1 dose of vaccine, 405(28.1%) patients received 2 doses of vaccine, 494(34.3%) patients received 3 doses of vaccine. Compared with patients aged 60 to 70 years, patients aged 70 to 80 years had longer viral shedding time (P<0.001). The viral shedding time in patients with hypertension and diabetes was longer than that in patients without hypertension and diabetes (P<0.05). In terms of vaccination, the viral shedding time of patients receiving 2 or 3 doses of vaccine was significantly shorter than that of patients receiving 1 dose of vaccine or none (P<0.05). There was a positive correlation between patient age and viral shedding time, with an R2=0.029 (P<0.001). Kaplan-Meier curve showed that there existed significant difference in viral shedding time between the patients with different vaccination doses (P<0.001), and patients with age >=70, hypertension and diabetes were all associated with prolonged viral shedding time (P<0.05). Cox regression analysis showed that the age >=70 years was a risk factor for prolonged viral shedding time, and 2 or 3 doses of vaccine was a protective factor for prolonged viral shedding time (P<0.05). Conclusions Among the elderly population, the viral shedding time would gradually increase with age. Patients who received >=2 doses of vaccine would have reduced viral shedding time compared with those who received <2 doses of vaccine.Copyright © 2022 Authors. All rights reserved.
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Objective To analyze the potential factors influencing the viral shedding time (duration of nucleic acid positivity) in elderly patients with mild and asymptomatic infection. Methods The clinical data of 1141 elderly (>=60 years) patients with mild and asymptomatic Omicron infection who were admitted to National Exhibition and Convention Center (Shanghai) Cabin Hospital from April 14, 2022 to May 1, 2022 were retrospectively collected, viral shedding time of patients were compared between different groups (age, gender, number of vaccination, hypertension, diabetes). Pearson analysis was adopted to analyze the relationship between age and viral shedding time. Kaplan-Meier curve and Log-rank test were used to evaluate the viral shedding time in elderly patients with different clinical characteristics. Multivariate Cox proportional-hazards regression model was adopted to analyze the factors influencing viral shedding time in elderly patients with Omicron. Results Among 1441 patients, 791(54.9%) males and 650(45.1%) females. There were 513(35.6%) patients receiving 0 dose of vaccine, 29(2.0%) patients received 1 dose of vaccine, 405(28.1%) patients received 2 doses of vaccine, 494(34.3%) patients received 3 doses of vaccine. Compared with patients aged 60 to 70 years, patients aged 70 to 80 years had longer viral shedding time (P<0.001). The viral shedding time in patients with hypertension and diabetes was longer than that in patients without hypertension and diabetes (P<0.05). In terms of vaccination, the viral shedding time of patients receiving 2 or 3 doses of vaccine was significantly shorter than that of patients receiving 1 dose of vaccine or none (P<0.05). There was a positive correlation between patient age and viral shedding time, with an R2=0.029 (P<0.001). Kaplan-Meier curve showed that there existed significant difference in viral shedding time between the patients with different vaccination doses (P<0.001), and patients with age >=70, hypertension and diabetes were all associated with prolonged viral shedding time (P<0.05). Cox regression analysis showed that the age >=70 years was a risk factor for prolonged viral shedding time, and 2 or 3 doses of vaccine was a protective factor for prolonged viral shedding time (P<0.05). Conclusions Among the elderly population, the viral shedding time would gradually increase with age. Patients who received >=2 doses of vaccine would have reduced viral shedding time compared with those who received <2 doses of vaccine. Copyright © 2022 Authors. All rights reserved.
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Background: The highly contagious SARS-CoV-2 is mainly transmitted by respiratory droplets and aerosols. Consequently, people are required to wear masks and maintain a social distance to avoid spreading of the virus. Despite the success of the commercially available vaccines, the virus is still uncontained globally. Given the tropism of SARS-CoV-2, a mucosal immune reaction would help to reduce viral shedding and transmission locally. Only seven out of hundreds of ongoing clinical trials are testing the intranasal delivery of a vaccine against COVID-19. Methods: In the current study, we evaluated the immunogenicity of a traditional vaccine platform based on virus-like particles (VLPs) displaying RBD of SARS-CoV-2 for intranasal administration in a murine model. The candidate vaccine platform, CuMVTT -RBD, has been optimized to incorporate a universal T helper cell epitope derived from tetanus-toxin and is self-adjuvanted with TLR7/8 ligands. Results: CuMVTT-RBD vaccine elicited a strong systemic RBD- and spike- IgG and IgA antibodies of high avidity. Local immune response was assessed and our results demonstrate a strong mucosal antibody and plasma cell production in lung tissue. Furthermore, the induced systemic antibodies could efficiently recognize and neutralize different variants of concern (VOCs) of mutated SARS-CoV-2 RBDs. Conclusion: Our data demonstrate that intranasal administration of CuMVTT-RBD induces a protective systemic and local specific antibody response against SARS-CoV-2 and its VOCs.
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Along with the increasing maturity of mobile information technology, mobile-based online learning has become one of the main teaching methods that all kinds of schools should adapt themselves to during the COVID-19 pandemic. However, online education physically isolates teachers from their students, hence weakening their interactions. In the context of this spatial isolation, the frequency of interactive behaviors and quality of communication in online education should be strengthened to improve the sustained learning results of learners. After reviewing the previous literature, a questionnaire investigating the influence of online instructional interaction level on sustained learning results was designed. By considering self-efficacy as a mediating variable, the mediating effect of self-efficacy on sustained learning results at the interactive level of online teaching was analyzed and the difference in sustained learning results that can be attributed to years of familiarity with online learning was measured. Results show that teacher-student interaction has significant positive effects on sustained learning results, whereas student-student interaction has significant positive effects on sustained learning results. Self-efficacy completely mediates the role of teacher-student interaction and student-student interaction in effectively and significantly improving sustained learning results. The duration of online learning has a significant effect on sustained learning results. Conclusions provide an important reference for enriching the learning activity design principles of instructional interaction level.
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Privacy safeguards are crucial, notably now with increased virtual conferencing usage during the Covid pandemic. In contrast to conventional facial expressions that are visually obvious to humans, micro-expressions are involuntary and transient facial expressions, commonly manifested involuntarily when we aim to withhold our emotions. Advanced micro-expression recognition techniques exist that can reveal the genuine emotions that people attempt to conceal, thus threatening individual emotional privacy, as fundamental human rights would dictate that one should have a choice of what emotion is being shown or not shown. We propose the novel universal adversarial perturbation-based approach - AdverFacial - for privacy concealment against automated micro-expression analysis via deep learning techniques. We derive the optimal strategy to achieve micro-expression misclassification with a high success rate, low perceptibility and cross neural network transferability. We perform experiments on two popular datasets with state-of-the-art microexpression spotting and recognition models and demonstrate our approach's effectiveness in emotional concealment. © 2022 IEEE
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This study aims to solve the problem of unwise judgment, decisions, and correspondingly dangerous behaviors caused by error health information to the elderly. Based on the MOA model and self-determination theory, this paper constructs a health information sharing model for the elderly and analyzes it with Amos's structural equation model. The study finds that media richness, health information literacy, perceived benefits, and negative emotions of the coronavirus epidemic positively influence health information sharing behavior. In contrast, perceived risks have a significant negative impact on health information sharing behavior. At the same time, media richness positively affects health information literacy, perceived benefits, and negative emotions of the coronavirus epidemic but has no significant impact on perceived risks. Health literacy positively affects perceived benefits but does not significantly affect the perceived risks and negative emotions of the coronavirus epidemic. This study aims to assist government and online social platforms in taking relevant measures under the background of normalization of the pandemic situation, controlling the spread of error health information among the elderly, and guiding the elderly to share health information better. © 2021 International Consortium for Electronic Business. All rights reserved.
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Objective To investigate the impact of the outbreak of coronavirus disease 2019 (COVID-19) as an intervention factor on residency training at different stages, and look into the enhancement effect of post-graduation medical training program based on competency of residency training, so as to provide reference for the optimization of medical education at the postgraduate stage. Methods After the initial success of COVID-19 prevention and control, 169 clinical postdoctoral trainess(clinical postdocs) and 515 graduate students specializing in clinical medicine(professional postdocs) were surveyed by an anonymous online questionnaire. To analyze the differences of cognition and self- evaluation of core competence between the two groups. Results There were 141 valid questionnaires collected from clinical postdocs (83.43%, 141/169) and 264 valid questionnaires collected from professional postdocs (51.26%, 264/515). In both groups, more than 85% of the students agreed or strongly agreed that they had a deeper understanding of the profession of doctors during the epidemic. The results of competency self-evaluation showed that, except for the items of "self-improvement", the self-evaluation scores of clinical postdoctoral students on other items were significantly higher than those of professional postdoctoral students (all P <0.05). Conclusions COVID-19, as a factor of emergency intervention, can improve the competency cognition of residents. The core-competency based post-graduation medical education model can comprehensively improve the students' comprehensive ability, which is an effective training program for residents. It is suggested that the vocational planning education for residents should be paid attention to in the stage of college education, and a new mode of college education that is closely combined with the post-graduation education should be further explored. © 2021 Thomson Reuters and Contributors.
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BACKGROUND: The significant morbidity and mortality resulted from the infection of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) call for urgent development of effective and safe vaccines. We report the immunogenicity and safety of an inactivated SARS-CoV-2 vaccine, KCONVAC, in healthy adults. METHODS: Phase 1 and phase 2 randomized, double-blind, and placebo-controlled trials of KCONVAC were conducted in healthy Chinese adults aged 18-59 years. The participants in the phase 1 trial were randomized to receive two doses, one each on Days 0 and 14, of either KCONVAC (5 mug/dose or 10 mug/dose) or placebo. The participants in the phase 2 trial were randomized to receive either KCONVAC (at 5 or 10 mug/dose) or placebo on Days 0 and 14 (0/14 regimen) or Days 0 and 28 (0/28 regimen). In the phase 1 trial, the primary safety endpoint was the proportion of participants experiencing adverse reactions/events within 28 days following the administration of each dose. In the phase 2 trial, the primary immunogenicity endpoints were neutralization antibody seroconversion and titer and anti-receptor-binding domain immunoglobulin G seroconversion at 28 days after the second dose. RESULTS: In the phase 1 trial, 60 participants were enrolled and received at least one dose of 5-mug vaccine (n = 24), 10-mug vaccine (n = 24), or placebo (n = 12). In the phase 2 trial, 500 participants were enrolled and received at least one dose of 5-mug vaccine (n = 100 for 0/14 or 0/28 regimens), 10-mug vaccine (n = 100 for each regimen), or placebo (n = 50 for each regimen). In the phase 1 trial, 13 (54%), 11 (46%), and 7 (58%) participants reported at least one adverse event (AE) after receiving 5-mug vaccine, 10-mug vaccine, or placebo, respectively. In the phase 2 trial, 16 (16%), 19 (19%), and 9 (18%) 0/14-regimen participants reported at least one AE after receiving 5-mug vaccine, 10-mug vaccine, or placebo, respectively. Similar AE incidences were observed in the three 0/28-regimen treatment groups. No AEs with an intensity of grade 3+ were reported, expect for one vaccine-unrelated serious AE (foot fracture) reported in the phase 1 trial. KCONVAC induced significant antibody responses;0/28 regimen showed a higher immune responses than that did 0/14 regimen after receiving two vaccine doses. CONCLUSIONS: Both doses of KCONVAC are well tolerated and able to induce robust immune responses in healthy adults. These results support testing 5-mug vaccine in the 0/28 regimen in an upcoming phase 3 efficacy trial. TRIAL REGISTRATION: http://www.chictr.org.cn/index.aspx (No. ChiCTR2000038804, http://www.chictr.org.cn/showproj.aspx?proj=62350;No. ChiCTR2000039462, http://www.chictr.org.cn/showproj.aspx?proj=63353).
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The ongoing coronavirus disease (COVID-19) pandemic is caused by a new coronavirus (severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2)) first reported in Wuhan City, China. From there, it has been rapidly spreading to many cities inside and outside China. Nowadays, more than 110 million cases with deaths surpassing 2 million have been recorded worldwide, thus representing a major health and economic issues. Rapid development of a protective vaccine against COVID-19 is therefore of paramount importance. Here, we demonstrated that the recombinantly expressed receptor-binding domain (RBD) of the spike protein can be coupled to immunologically optimized virus-like particles derived from cucumber mosaic virus (CuMV<sub>TT</sub>). The RBD displayed CuMV<sub>TT</sub> bound to ACE2, the viral receptor, demonstrating proper folding of RBD. Furthermore, a highly repetitive display of the RBD on CuMV<sub>TT</sub> resulted in a vaccine candidate that induced high levels of specific antibodies in mice, which were able to block binding of the spike protein to ACE2 and potently neutralize SARS-CoV-2 virus in vitro.
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COVID-19 is a novel disease caused by SARS-CoV-2 which has conquered the world rapidly resulting in a pandemic that massively impacts our health, social activities, and economy. It is likely that vaccination is the only way to form "herd immunity" and restore the world to normal. Here we developed a vaccine candidate for COVID-19 based on the virus-like particle AP205 displaying the spike receptor binding motif (RBM), which is the major target of neutralizing antibodies in convalescent patients. To this end, we genetically fused the RBM domain of SARS-CoV-2 to the C terminus of AP205 of dimerized capsid proteins. The fused VLPs were expressed in E. coli, which resulted in insoluble aggregates. These aggregates were denatured in 8 M urea followed by refolding, which reconstituted VLP formation as confirmed by electron microscopy analysis. Importantly, immunized mice were able to generate high levels of IgG antibodies recognizing eukaryotically expressed receptor binding domain (RBD) as well as spike protein of SARS-CoV-2. Furthermore, induced antibodies were able to neutralize SARS-CoV-2/ABS/NL20. Additionally, this vaccine candidate has the potential to be produced at large scale for immunization programs.
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Objective: To study the pathological changes of the spleen in patients with COVID-19 and to analyze the relationship between the weakened immune system and splenic lesions. Methods: Postmortem needle autopsies from the spleen were carried out on 10 patients who died from COVID-19 in Wuhan. Routine hematoxylin and eosin (HE) staining was used to observe the pathological changes. The changes of lymphocytes were studied further with immunohistochemistry.RT-PCR was used to detect 2019-nCoV RNA in the spleen. In addition,the Epstein-Barr virus (EBV) was detected by in situ hybridization, and coronavirus particles were detected by transmission electron microscopy in 2 cases. Results: There were 7 males and 3 females, with an average age of 68.3 years.Of the 10 cases, 4 had cancer history and another 4 had other underlying diseases respectively.Cough, fever, malaise and dyspnea were the main clinical symptoms.The time from onset to death was 15-45 days.Ten cases patients had normal or slight increase in peripheral blood leukocyte count in the early stage of the disease, 6 cases had significant increase before death. Five patients' peripheral blood lymphocyte count decreased in the early stage of the disease, and 10 patients' peripheral blood lymphocyte count decreased significantly before the disease progressed or died. Seven cases were treated with corticosteroid (methylprednisolone ≤40 mg/d, not more than 5 days). Histopathological examination showed that the cell composition of the spleen decreased, white pulp atrophied at different levels, meanwhile lymphoid follicles decreased or absent;in addition, the ratio of red pulp to white pulp increased with varying degrees. In 7 cases, more neutrophil infiltration was found, and in 5 cases, scattered plasma cell infiltration was found. Macrophage proliferation and hemophagocytic phenomena in a few cells were found in a case. Meanwhile, necrosis and lymphocyte apoptosis were detected in 2 cases, small artery thrombosis and spleen infarction in 1 case, and fungal infection in 1 case. The results of immunohistochemistry showed that the T and B lymphocyte components of the spleen in all cases decreased in varying degrees. CD20(+) B cells were found to accumulate in the lymphoid sheath around the splenic artery in 8 cases. However, CD20 and CD21 immunostaining in 2 cases showed that the number of white pulp was almost normal, and splenic nodules were atrophic. CD3(+), CD4(+) and CD8(+)T cells were decreased. In 9 cases,CD68(+) macrophages were no significant changes in the distribution and quantity. While more CD68(+) cells were found in the medullary sinuses of 1 case (related to fungal infection). Few CD56(+) cells were found. EBV was negative by in situ hybridization. RT-PCR was used to detect the nucleic acid of 2019-nCoV. One of 10 cases was positive, 39 years old,who was the youngest patient in this group, and the other 9 cases were negative. Coronavirus particles were found in the cytoplasm of macrophage under electron microscope in 2 cases. Conclusions: The death of COVID-19 occurs mainly in the elderly, and some cases have no underlying diseases. Spleen may be one of the organs directly attacked by the virus in some patients who died from COVID-19. T and B lymphocyte in the spleen decrease in varying degrees, lymphoid follicles are atrophied, decreased or absent, and the number of NK cells do not change significantly. And the pathological changes of the spleen are not related to the use of low dose corticosteroid, which may be related to the direct attack of virus and the attack of immune system on its own tissues.