Antibody responses to BNT162b2 vaccination in Japan: Monitoring vaccine efficacy by measuring IgG antibodies against the receptor binding domain of SARS-CoV-2

BACKGROUNDTo fight severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), mass vaccination has begun in many countries. To investigate the usefulness of a serological assay to predict vaccine efficacy, we analyzed the levels of IgG, IgM, and IgA against the receptor binding domain (RBD) of SARS-CoV-2 in the sera from BNT162b2 vaccinated individuals in Japan. METHODSThis study included 219 individuals who received two doses of BNT162b2. The levels of IgG, IgM, and IgA against RBD were measured by enzyme-linked immunosorbent assay before and after the first and second vaccination, respectively. The relationship between antibody levels and several factors including age, gender, and hypertension were analyzed. Virus-neutralizing activity in sera was measured to determine the correlation with the levels of antibodies. A chemiluminescent enzyme immunoassay (CLEIA) method to measure IgG against RBD was developed and validated for the clinical setting. RESULTSThe levels of all antibody isotypes were increased after vaccination. Among them, RBD-IgG was dramatically increased after the second vaccination. The IgG levels in females were significantly higher than in males. There was a negative correlation between age and IgG levels in males. The IgG levels significantly correlated with the neutralizing activity. The CLEIA assay measuring IgG against RBD showed a reliable performance and a high correlation with neutralizing activity. CONCLUSIONSMonitoring of IgG against RBD is a powerful tool to predict the efficacy of SARS-CoV-2 vaccination and provides useful information in considering a personalized vaccination strategy for COVID-19.

Reliability of serological tests for COVID-19: Comparison of three immunochromatography test kits for SARS-CoV-2 antibodies.

BackgroundSeveral immunochromatographic serological test kits have been developed to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific antibodies, but their relative performance and potential clinical utility is unclear. MethodsThree commercially available serological test kits were evaluated using 99 serum samples collected from 29 patients diagnosed with coronavirus disease 2019 (COVID-19). ResultsThe IgM antibody-positive rates of the three serological test kits for samples taken at the early stage of the disease (0-6 days after onset) were 19.0%, 23.8%, and 19.0%, respectively. The IgM antibody-positive rates over the entire period were 21.2%, 60.6%, and 15.2%, respectively. The IgG antibody-positive rates for samples taken after 13 days of onset were 100.0%, 97.6%, and 97.6%, respectively. ConclusionThere were large differences among the results of the three test kits. Only few cases showed positive results for IgM in the early stage of disease and the IgM antibody-positive rates over the entire period were low, suggesting that the kits used in this study were unsuitable for diagnosis of COVID-19. The IgG antibody was positive in almost all samples after 13 days of onset, suggesting that it may be useful for determining infections in the recent past.

Light environment within a leaf. II. Progress in the past one-third century.

Studies directly related to light environments within a leaf, conduced mainly in the past one-third century, are reviewed. In particular, studies that revealed the profiles of light absorption and photosynthetic capacity are highlighted. Progress in this research field has been accelerated by devising innovative techniques. Roles of the main photosynthetic tissues, the palisade and spongy tissues, as the light guide and diffuser, respectively, are discussed. When the leaf is illuminated with diffuse light, light is absorbed more by the chloroplasts located near the illuminated surface. The meanings of the occupation of the mesophyll surfaces facing the intercellular spaces by chloroplasts and chloroplast movement are also discussed. The discrepancy between the light absorption profile and that of photosynthetic capacity is examined most intensively.

Live trauma surgery demonstration with a porcine model is valuable training for physicians and nurses / 医学教育

Sources of research funding: We gratefully acknowledge the support of the 17th Congress of the Japanese Society for Emergency Medicine support of this program.<br>Ethical considerations: The program was conducted after receiving approval from the Institutional Animal Experiment Committee of the Jichi Medical University, and in accordance with the Institutional Regulation for Animal Experiments and Fundamental Guideline for Proper Conduction of Animal Experiment and Related Activities in Academic Research Institutions under the jurisdiction of the Ministry of Education, Culture, Sports, Science and Technology of Japan. It was approved on April 9th, 2014. The approval number is 14-225.<br>Disclosure of conflicts of interests: We gratefully acknowledge the contributions of personnel from Panasonic Corp. who enabled the interactive communication system.<br>Abstract<br>Introduction: Live surgery demonstrations have been widely used in surgical education. However, they cannot be used to demonstrate trauma surgery due to the emergency situation and lack of informed consent. The aim of this study was to conduct a live demonstration of trauma surgery with a porcine model to increase educational opportunities in trauma surgery.<br>Methods: Live demonstration was conducted at the Center for Development of Advanced Medical Technology (CDAMtec) , Jichi Medical University, Japan. An experienced trauma surgeon instructed three trainees during a live demonstration using pre-planned injuries in a porcine model. A six-point Likert Scale was used on a written survey to determine the value of the program to the viewers. Free-form written comments were also obtained from the participants. Live images of the surgical field were transmitted to a lecture room by a closed wireless LAN with interactive bidirectional audio capability.<br>Results: Eighty-three participants viewed this live demonstration and completed the questionnaire. Participants were highly satisfied with the live demonstration (mean survey scores: 4.6-5.1/6) , and gave very positive feedback concerning the educational value of this program. Nine free-form comments were submitted, which revealed that the participants felt they could acquire concrete skills for trauma surgery.<br>Discussion: Live demonstrations for trauma surgery using a porcine model are a feasible and effective educational tool to demonstrate technical procedures and non-technical skills, with possible added advantages regarding the ethical considerations of performing a live surgery demonstration.

Analysis of ankyrin-B gene mutations in patients with long QT syndrome / 南方医科大学学报

<p><b>OBJECTIVE</b>To identify the ankyrin-B gene mutations that cause long QT syndrome (LQTS) and determine the prevalence of such mutations in Japanese patients with LQTS.</p><p><b>METHODS</b>We conducted a search for ankyrin-B gene mutation in 78 unrelated patients with LQTS (28 males and 50 females, aged 2 to 89 years). With informed consent from all the subjects and/or their parents, genomic DNA was purified from the white blood cells of the patients and amplified using polymerase chain reaction (PCR). Single-strand conformational polymorphism (SSCP) analysis of the amplified DNA was performed to screen for mutations and aberrant SSCP products were isolated and sequenced by dye terminator cycle sequencing method using an automated fluorescent sequencer. PCR and restriction fragment length polymorphism (PCR-RFLP) analysis was carried out to further confirm the missense mutations by comparison with samples from 150 normal healthy individuals.</p><p><b>RESULTS</b>We identified a T to A transition mutation at position 4,603 in exon 40, resulting in the substitution of arginine for a tryptophan at amino acid residue 1,535 (W1535R) in the regulatory domain of 220-kD ankyrin-B, which is a highly conserved domain shared by different species.</p><p><b>CONCLUSION</b>This novel missense mutation in the ankyrin-B gene may be a cause of type 4 LQTS. Ankyrin-B gene mutation might not play the major role in LQTS in Japanese.</p>