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The budding yeast Saccharomyces cerevisiae is commonly used as an expression platform for the production of valuable compounds. Yeast‐based genetic research can uniquely utilize auxotrophy in transformant selection: auxotrophic complementation by an auxotrophic marker gene on exogenous DNA (such as plasmids). However, the number of required auxotrophic nutrients restricts the number of plasmids maintained by the cells. We, therefore, developed novel Δ10 strains that are auxotrophic for 10 different nutrients and new plasmids with two multiple cloning sites and auxotrophic markers for use in Δ10 strains. We confirmed that Δ10 strains were able to maintain 10 types of plasmids. Using plasmids encoding model proteins, we detected the co‐expression of 17 different genes in Δ10 cell lines. We also constructed Δ9 strains that exhibited auxotrophy for nine nutrients and increased growth compared to Δ10. This study opens a new avenue for the co‐expression of a large number of genes in eukaryotic cells. [ABSTRACT FROM AUTHOR]

Therapeutic drug monitoring (TDM) is a routine clinical practice used to individualize drug dosing to maintain drug efficacy and minimize the consequences of overexposure. TDM is applied to many drug classes, including immunosuppressants, antineoplastic agents, and antibiotics. Considerable effort has been made to establish routine TDM practices for each drug. However, because TDM has been developed within the context of specific drugs, there is insufficient understanding of historical trends within the field of TDM research as a whole. In this study, we employed text-mining approaches to explore trends in the TDM research field. We first performed a PubMed search to determine which drugs and drug classes have been extensively studied in the context of TDM. This investigation revealed that the most commonly studied drugs are tacrolimus, followed by cyclosporine and vancomycin. With regard to drug classes, most studies focused on immunosuppressants, antibiotics, and antineoplastic agents. We also subjected PubMed records of TDM-related studies to a series of text-mining pipelines. Our analyses revealed how TDM research has evolved over the years, thereby serving as a cornerstone for forecasting future research trends.

A recent strategy in gene therapy has been using antiviral genes that are delivered to uninfected cells, either as RNA or DNA, to provide intracellular protection from human immunodeficiency virus type-1 (HIV-1) infection. Antisense oligonucleotides that are complementary to specific target genes suppress gene expression. A variety of techniques are available to enhance the cellular uptake and pharmacological effectiveness of antisense oligonucleotides, both in vitro and in vivo. We investigated the intracellular and tissue uptake of an oligonucleotide/cationic lipid complex, using a fluorescently labeled oligonucleotide. The antisense oligonucleotide was designed against the HIV-1 gag gene sequence. A T-cell line (MT-4) and PHA-stimulated peripheral blood mononuclear cells (PBMCs) were both infected with HIV-1(NL432) at an MOI of 0.01. One h later, both cultures were washed and treated with medium containing 1 microM antisense oligonucleotide. After a 3-day interval, the HIV-1 antigen expression was monitored by an indirect immunofluorescence assay. At 3 days post infection, we confirmed that p24 antigen production was inhibited by the antisense oligonucleotide/cationic lipid complex at a 1/10 ratio in the PBMCs, using enzyme-linked immunosorbent assay (ELISA). We also confirmed the intracellular existence of the complex by fluorescent microscopy. We investigated different means of transporting the antisense oligonucleotide/cationic lipid complex to mouse tissues by intravenous, intraperitoneal and subcutaneous injections. We observed that the anti-HIV-1 activity of the antisense oligonucleotide/cationic lipid complex was the result of enhanced cellular uptake, both in vitro and in vivo. Therefore, the antisense oligonucleotide/cationic lipid complex is an excellent system for the transport and delivery of genes to target cells, as it is effective both in vitro and in vivo.