Investigation of differentiation conditions for canine duodenum, upper jejunum, and ileum crypt-derived cells for drug transport and metabolism.

Three-dimensional spheroid cultures of crypts from the duodenum, upper jejunum, and ileum of beagle dog were established to investigate species differences in drug transport and metabolism. Four differentiation conditions were tested using jejunum-derived cells: base medium (BM; without Wnt3a, R-spondin 3, and Noggin), BM plus epidermal growth factor (BM + EGF), EGF/Noggin/R-spondin 3 (ENR) for liquid-liquid interface (LLI), and ENR for air-liquid interface (ALI). Transepithelial electrical resistance (Ω·cm) varied among conditions (102-125 for BM and ALI vs 911-1106 for BM + EGF and ENR), whereas the apparent permeability coefficient (P) of Lucifer yellow was similar.

Characterization of intestinal transporters in human ileal spheroid-derived differentiated cells for the prediction of intestinal drug absorption.

This study aimed to characterize the functional properties of human spheroid-derived differentiated cells for absorption, distribution, metabolism, and excretion studies. Three-dimensional human intestinal spheroids were successfully established from crypts isolated from fresh surgical specimens of the terminal ileum. The mRNA expression of major intestinal transporters and drug-metabolizing enzymes was tested.

Three- and four-stranded nucleic acid structures and their ligands.

Nucleic acids have the potential to form not only duplexes, but also various non-canonical secondary structures in living cells. Non-canonical structures play regulatory functions mainly in the central dogma. Therefore, nucleic acid targeting molecules are potential novel therapeutic drugs that can target 'undruggable' proteins in various diseases.

Development of the serotonin release assay with enterochromaffin cell-rich human intestinal organoids for the risk evaluation of drug-induced emesis.

Drug-induced emesis is one of the major symptoms of gastrointestinal toxicity. Preclinical risk assessment of emesis has been challenging owing to the lack of suitable animal models or in vitro assay systems. One of the triggers of emesis is an excessive serotonin (5-HT) release from enterochromaffin (EC) cells in the intestinal tract, which activates the vomiting center in the brain stem and elicits the vomiting reflex.

NRAS DNA G-quadruplex-targeting molecules for sequence-selective enzyme inhibition.

Sequence-selective G-quadruplex ligands are valuable for controlling gene expression. Here, we established a new fluorescence displacement assay using a NRAS G-quadruplex selective fluorescent probe to identify sequence-selective DNA G-quadruplex ligands. These sequence-selective NRAS G-quadruplex ligands retained their binding affinity even in the presence of excessive human telomeric DNA G-quadruplex and regulated enzymatic activities in a sequence-selective manner.

Evaluation of the risk of diarrhea induced by epidermal growth factor receptor tyrosine kinase inhibitors with cultured intestinal stem cells originated from crypts in humans and monkeys.

Severe diarrhea is a common side effect of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). We aimed to evaluate the risk of EGFR-TKI-induced diarrhea using spheroids of human and monkey crypt-derived intestinal stem cells. Intestinal spheroids exhibited higher toxic susceptibility to EGFR-TKIs than Caco-2 cells.

Simple and fast screening for structure-selective G-quadruplex ligands.

Structural selectivity of G-quadruplex ligands is essential for cellular applications since there is an excess of nucleic acids forming duplex structures compared to G-quadruplex structures in living cells. In this study, we developed new structure-selective G-quadruplex ligands utilizing a simple and fast screening system. The affinity, selectivity, enzymatic inhibitory activity and cytotoxicity of the structure-selective G-quadruplex ligands were demonstrated along with a structural selectivity-cytotoxicity relationship of G-quadruplex ligands.

Quantitative prediction of pharmacokinetic properties of drugs in humans: Recent advance in in vitro models to predict the impact of efflux transporters in the small intestine and blood-brain barrier.

Efflux transport systems are essential to suppress the absorption of xenobiotics from the intestinal lumen and protect the critical tissues at the blood-tissue barriers, such as the blood-brain barrier. The function of drug efflux transport is dominated by various transporters. Accumulated clinical evidences have revealed that genetic variations of the transporters, together with coadministered drugs, affect the expression and/or function of transporters and subsequently the pharmacokinetics of substrate drugs.

Photosensitizers Based on G-Quadruplex Ligand for Cancer Photodynamic Therapy.

G-quadruplex (G4) is the non-canonical secondary structure of DNA and RNA formed by guanine-rich sequences. G4-forming sequences are abundantly located in telomeric regions and in the promoter and untranslated regions (UTR) of cancer-related genes, such as and . Extensive research has suggested that G4 is a potential molecular target for cancer therapy.

Yield Visualization Based on Farm Work Information Measured by Smart Devices.

This paper proposes a new approach to visualizing spatial variation of plant status in a tomato greenhouse based on farm work information operated by laborers. Farm work information consists of a farm laborer's position and action. A farm laborer's position is estimated based on radio wave strength measured by using a smartphone carried by the farm laborer and Bluetooth beacons placed in the greenhouse.

In vitro synthesis of polyhydroxyalkanoates using thermostable acetyl-CoA synthetase, CoA transferase, and PHA synthase from thermotorelant bacteria.

Thermostable enzymes are required for the rapid and sustainable production of polyhydroxyalkanoate (PHA) in vitro. The in vitro synthesis of PHA using the engineered thermostable synthase PhaC1(STQK) has been reported; however, the non-thermostable enzymes acetyl-CoA synthetase (ACS) and CoA transferase (CT) from mesophilic strains were used as monomer-supplying enzymes in this system. In the present study, acs and ct were cloned from the thermophilic bacteria Pelotomaculum thermopropionicum JCM10971 and Thermus thermophilus JCM10941 to construct an in vitro PHA synthesis system using only thermostable enzymes.

Xeno-free proliferation of human bone marrow mesenchymal stem cells.

The proliferation of human bone marrow mesenchymal stem cells (MSCs) employing xeno-free materials not containing fetal calf serum (FCS) and porcine trypsin was investigated for the regenerative medicine of cartilage using MSCs. Four sequential subcultivations of MSCs using a medium containing 10% FCS and recombinant trypsin (TrypLESelect™) resulted in cell growth comparable to that with porcine trypsin. There was no apparent difference in the cell growth and morphology between two kinds of MSC stored in liquid nitrogen using 10% FCS plus DMSO or serum-free TC protector™.

Molecular characterization of the essential response regulator protein YycF in Bacillus subtilis.

The response regulator YycF is essential for cell growth in gram-positive bacteria including Bacillus subtilis, Staphylococcus aureus and Streptococcus pneumoniae. To study the function of YycF in the essential process, we characterized a YycF (H215P) mutation that caused temperature-sensitive growth in B. subtilis.

Isolation and characterization of inhibitors of the essential histidine kinase, YycG in Bacillus subtilis and Staphylococcus aureus.

The set of sensor kinase YycG and response regulator YycF is the only essential two-component system (TCS) in Bacillus subtilis and Staphylococcus aureus. We have developed a screening method for antibacterial agents that inhibit YycG, the essential histidine kinase (HK). To increase screening sensitivity, a temperature-sensitive yycF mutant (CNM2000) of B.