Development of an in vitro screening system for synthetic signal peptide in mammalian cell-based protein production.

Optimizing appropriate signal peptides in mammalian cell-based protein production is crucial given that most recombinant proteins produced in mammalian cells are thought to be secreted proteins. Until now, most studies on signal peptide in mammalian cells have replaced native signal peptides with well-known heterologous signal peptides and bioinformatics-based signal peptides. In the present study, we successfully established an in vitro screening system for synthetic signal peptide in CHO cells by combining a degenerate codon-based oligonucleotides library, a site-specific integration system, and a FACS-based antibody detection assay.

Amplification of EBNA-1 through a single-plasmid vector-based gene amplification system in HEK293 cells as an efficient transient gene expression system.

Our previous work showed that there is a limitation in the use of dihydrofolate reductase (dhfr)/methotrexate (MTX)-mediated gene amplification systems in dhfr-non-deficient HEK293 cells, as endogenous dhfr may interfere with the amplification process. In the present study, we successfully generated Epstein-Barr virus nuclear antigen-1 (EBNA-1)-amplified HEK293 cells in a dhfr-non-deficient HEK293 cell background using a single-plasmid vector-based gene amplification system with shRNA targeting the 3'-UTR of endogenous dhfr. The introduction of this shRNA efficiently downregulated the expression of endogenous dhfr in the HEK293 cells without affecting exogenous dhfr expression.

Quantitative assessment of deep-seated CO leakage around CO-rich springs with low soil CO efflux using end-member mixing analysis and carbon isotopes.

This study examined a mountainous area with two hydrochemically distinct CO-rich springs to understand the origin, flow, and leakage of CO, which may provide implications for precise monitoring of CO leakage in geological carbon storage (GCS) sites. The carbon isotopic compositions of dissolved inorganic carbon (DIC) in CO-rich water (δC) and those of soil CO (δC) indicated a deep-seated CO supply to the near-surface environment in the study area. The hydrochemical difference (e.

Annual Prevalence and Incidence of Schizophrenia and Similar Psychotic Disorders in the Republic of Korea: A National Health Insurance Data-Based Study.

Objective: We conducted this study to address the incidence and prevalence of schizophrenia and similar psychosis in South Korea with Health Insurance Review and Assessment (HIRA) database.

Methods: We used HIRA database, which includes diagnostic information of nearly all Korean nationals to collect number of cases with diagnosis of schizophrenia and schizophrenia-similar disorders (SSP), including schizophreniform, acute/transient psychotic disorders, schizoaffective disorders, and other/unspecific nonorganic psychosis (ICD-10 codes F20/23/25/28/29) between 2010 and 2015. The annual prevalence and incidence were calculated using the population data from the Korean Statistical Office.