Vaccination with Span, an antigen guided by SARS-CoV-2 S protein evolution, protects against challenge with viral variants in mice

SARS-CoV-2 continues to accumulate mutations to evade immunity, leading to breakthrough infections after vaccination. How researchers can anticipate the evolutionary trajectory of the virus in advance in the design of next-generation vaccines requires investigation. Here, we performed a comprehensive study of 11,650,487 SARS-CoV-2 sequences, which revealed that the SARS-CoV-2 spike (S) protein evolved not randomly but into directional paths of either high infectivity plus low immune resistance or low infectivity plus high immune resistance. The viral infectivity and immune resistance of variants are generally incompatible, except for limited variants such as Beta and Kappa. The Omicron variant has the highest immune resistance but showed high infectivity in only one of the tested cell lines. To provide cross-clade immunity against variants that undergo diverse evolutionary pathways, we designed a new pan-vaccine antigen (Span). Span was designed by analyzing the homology of 2675 SARS-CoV-2 S protein sequences from the NCBI database before the Delta variant emerged. The refined Span protein harbors high-frequency residues at given positions that reflect cross-clade generality in sequence evolution. Compared with a prototype wild-type (Swt) vaccine, which, when administered to mice, induced serum with decreased neutralization activity against emerging variants, Span vaccination of mice elicited broad immunity to a wide range of variants, including those that emerged after our design. Moreover, vaccinating mice with a heterologous Span booster conferred complete protection against lethal infection with the Omicron variant. Our results highlight the importance and feasibility of a universal vaccine to fight against SARS-CoV-2 antigenic drift.

Sustainable Passive Design for Building Performance of Healthy Built Environment in the Lingnan Area

Having a healthy built environment becomes increasingly important, especially under the effects of COVID-19. This paper intends to combine sustainable goals based on climate change with passive design principles to achieve a healthy built environment regarding the building performance of residential buildings. The Yuedao Residential Community in the Lingnan area was taken as an example for the research. Based on relevant standards of healthy buildings, the thermal, light, and acoustic environment requirements were determined. The methods of building performance simulation and on-site measurement were used to quantify the research object environments. Then, the outcomes were obtained based on these standards. As observed, the thermal environment's adaptive thermal comfort level was level III. It was hot indoors, but the light and acoustic environments met the requirements. Building designs based on a built environment optimized by external shading systems aim to solve problems through building performance simulation and qualitative analysis. After optimization, the thermal environment improved. According to the literature review, this research focused on a healthy built environment with a sustainable passive design in terms of building performance. A research workflow was established that could be used for more practical research, with abundant research methods. The problems were solved to varying degrees, and the Lingnan architectural culture was preserved. Moreover, this research filled the gap in interactive research on healthy built environments with sustainable passive design regarding building performance.

[Management strategy for the resumption of regular diagnosis and treatment in gastrointestinal surgery department during the outbreak of coronavirus disease 2019 (COVID-19)].

Acute abdomen, abdominal trauma, gastrointestinal bleeding and gastrointestinal tumors are the main conditions that are routinely treated in gastrointestinal surgery department with high incidence and critical condition. These conditions need emergency or selective operations. During the outbreak of the coronavirus disease 2019 (COVID-19), it's a great challenge for us to meet the patients' requirement under the situation. As the COVID-19 was brought under control in China, the Department of General Surgery in Nanfang Hospital resumed regular medical services gradually. Based on our clinical practice, the four major measures of strengthening pre-hospital screening, perioperative prevention and control, medical staff protection, and ward management were adopted. These main measures include the strict implementation of the appointment system and triage system before admission; the conduction of epidemiological and preliminary screening of viral nucleic acids; the chest CT examination during the perioperative period to re-screen COVID-19; the reduction of the risk of droplets and aerosol transmission; the minimally invasive surgery combined with enhanced recovery program in order to reduce patient's susceptibility and shorten the length of postoperative hospital stay; the reinforcement of specific infection control training for medical staff; the strict implementation of hierarchical protection; the establishment of gastrointestinal surgery prevention and control system; the rehearsal of emergency exercise; the installation of quarantine wards; the screening and management of family care-givers; the strict disinfection of environment and materials. Our preliminary practice shows that following the work guidelines issued by the Guangdong Province COVID-19 Prevention and Control Office and adopting precise management strategies in combination with the specific clinical features of gastrointestinal surgery, it is possible to safely resume regular care for the patients and comply to epidemic control at the same time.