SARS-CoV-2 Seroprevalence among Healthcare Workers in General Hospitals and Clinics in Japan

Coronavirus disease 2019 (COVID-19) has become a serious public health problem worldwide. In general, healthcare workers are considered to be at higher risk of COVID-19 infection. However, the prevalence of COVID-19 among healthcare workers in Japan is not well characterized. In this study, we aimed to examine the seroprevalence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) antibodies among 2160 healthcare workers in hospitals and clinics that are not designated to treat COVID-19 patients in Japan. The prevalence of SARS-CoV-2 immunoglobulin G was 1.2% in August and October 2020 (during and after the second wave of the pandemic in Japan), which is relatively higher than that in the general population in Japan (0.03-0.91%). Because of the higher risk of COVID-19 infection, healthcare workers should be the top priority for further social support and vaccination against SARS-CoV-2.

The amino acid sequence of mitogenic lectin-B from the roots of pokeweed (Phytolacca americana)

The complete amino acid sequence of pokeweed lectin-B (PL-B) has been analyzed by first sequencing seven lysylendopeptidase peptides derived from the reduced and S-pyridylethylated PL-B and then connecting them by analyzing the arginylendopeptidase peptides from the reduced and S-carboxymethylated PL-B. PL-B consists of 295 amino acid residues and two oligosaccharides linked to Asn96 and Asn139, and has a molecular mass of 34,493 Da. PL-B is composed of seven repetitive chitin-binding domains having 48-79% sequence homology with each other. Twelve amino acid residues including eight cysteine residues in these domains are absolutely conserved in all other chitin-binding domains of plant lectins and class I chitinases. Also, it was strongly suggested that the extremely high hemagglutinating and mitogenic activities of PL-B may be ascribed to its seven-domain structure.

[Rupture of hepatocellular carcinoma with multiple pulmonary metastasis successfully treated by transcatheter arterial embolization (TAE) of tumor: a case report]

A 66-year-old woman was hospitalized in a state of shock with rupture of hepatocellular carcinoma and multiple pulmonary metastasis. Her bleeding was successfully controlled by emergency transcatheter arterial embolization with Lipiodol (Lp-TAE). Treatments with UFT, OK-432 and two additional Lp-TAE caused the disappearance of pulmonary metastasis with AFP levels decreased and natural killer cell activity increased. The patient died one and a half years after the emergency Lp-TAE. The disappearance of pulmonary metastatic lesions seemed to be caused by improvement of the patient's immunity, which related to the regression of primary tumor after Lp-TAE. It was suggested that Lp-TAE is worth undertaking even in rupture of hepatocellular carcinoma with remote metastatic lesions.