Light intensity-dependent arrestin switching for inactivation of a light-sensitive GPCR, bistable opsin.

Inactivation of most light-sensitive G protein-coupled receptor (GPCR) opsins involves arrestin binding to terminate cell responses. In the zebrafish pineal organ, UV sensitive parapinopsin 1 (PP1)-expressing cells exhibit color opponency through photoequilibria between two photo-interconvertible states of PP1. The amount of visible light-sensitive active states (photoproducts) is crucial for generating color opponency, raising questions about how and what arrestins are involved in PP1 inactivation.

Functional identification of an opsin kinase underlying inactivation of the pineal bistable opsin parapinopsin in zebrafish.

In the pineal organ of zebrafish larvae, the bistable opsin parapinopsin alone generates color opponency between UV and visible light. Our previous study suggested that dark inactivation of the parapinopsin photoproduct, which activates G-proteins, is important for the regulation of the amount of the photoproduct. In turn, the photoproduct is responsible for visible light sensitivity in color opponency.

Four Cases of Coronavirus Disease 2019 Transferred from a Cruise Ship.

An outbreak of coronavirus disease 2019 (COVID-19) that began in Wuhan, China, has spread rapidly to many countries. We herein report four cases of COVID-19 confirmed in Japan among passengers of the cruise ship Diamond Princess and describe the clinical features, clinical course, and progression of chest computed tomographic images, chest radiographs, and treatment. Although these four patients had symptoms that included a fever, malaise, runny nose, and cough, one patient had no symptoms on admission.

Clinicopathologic and Immunohistochemical Findings from Autopsy of Patient with COVID-19, Japan.

An autopsy of a patient in Japan with coronavirus disease indicated pneumonia lung pathology, manifested as diffuse alveolar damage. We detected severe acute respiratory syndrome coronavirus 2 antigen in alveolar epithelial cells and macrophages. Coronavirus disease is essentially a lower respiratory tract disease characterized by direct viral injury of alveolar epithelial cells.

Glycated human serum albumin enhances macrophage inflammatory protein-1beta mRNA expression through protein kinase C-delta and NADPH oxidase in macrophage-like differentiated U937 cells.

Background: In a previous report (Higai K et al., Biol Pharm Bull, 2007), glycated human serum albumin (Glc-HSA) was found to induce interleukin-8 (IL-8) mRNA expression in human monocyte-derived U937 cells through a reactive oxygen species (ROS)-dependent pathway; however, Glc-HSA signaling has not been elucidated in macrophages.

Methods: U937 cells were differentiated by treatment with 50 ng/mL phorbol 12-myristate 13-acetate (PMA) for 2 days and the macrophage-like differentiated U937 (differentiated U937) cells were stimulated with Glc-HSA and glycolaldehyde dimer-modified HSA (GA-HSA) in the presence of various signaling inhibitors.