Biochemical and crystallographic assessments of the effect of 4,6-O-disulfated disaccharide moieties in chondroitin sulfate E on chondroitinase ABC I activity.

O-sulfated N-acetyl-d-galactosamine (GalNAc) residues in chondroitin sulfate (CS) play a crucial role in chondroitinase ABC I (cABC-I) activity. CSA containing mainly 4-O-monosulfated GalNAc was a good substrate for the enzyme, but not CSE containing mainly 4,6-O-disulfated GalNAc [GalNAc(4S,6S)]. Each CS isomer exhibits structural heterogeneity; CSE has di-sulfated disaccharide units and mono-sulfated disaccharide units.

Advances in Understanding the Mechanism of Ophthalmic Viscosurgical Device Retention in the Anterior Chamber or on the Corneal Surface during Ocular Surgery.

Retention durability, especially in the eye, is one of the most important properties of ophthalmic viscosurgical devices (OVDs) during ocular surgery. However, the information on the physical properties of OVDs is insufficient to explain their retention durability. The purpose of this study is to clarify the mechanism of OVD retention to improve understanding of the behavior of OVDs during ocular surgery.

Construction of patient-derived tumor models to evaluate anticancer agents and cancer immunotherapy.

An assay system using patient-derived tumor models represents a promising preclinical cancer model that replicates the disease better than traditional cell culture models. Patient-derived tumor organoid (PDO) and patient-derived tumor xenograft (PDX) models have been previously established from different types of human tumors to recapitulate accurately and efficiently their tissue architecture and function. However, these models have low throughput and are challenging to construct.

Quantitative Assessment of Ophthalmic Viscosurgical Devices on Visibility, Spreadability, and Durability as Corneal Wetting Agents for the Wet Shell Technique.

Purpose: To evaluate ophthalmic viscosurgical devices (OVDs) as corneal wetting agents for the wet shell technique, a common procedure in Japan to maintain the wettability of corneal surfaces.

Methods: We surveyed Japanese ophthalmologists to determine the current state of the wet shell technique. After developing three ex vivo testing methods, we evaluated the corneal wetting properties of OVDs including 3% hyaluronic acid (HA) solution and OVD products, Opegan, Opelead, Viscoat, Shellgan, Discovisc, and Opegan-Hi.

D-sorbitol can keep the viscosity of dispersive ophthalmic viscosurgical device at room temperature for long term.

The combination of 3% sodium hyaluronate (HA) and 4% sodium chondroitin sulfate (CS) is used as a dispersive ophthalmic viscosurgical device (OVD) during cataract surgery. For most OVDs containing HA, storage at 2-8 °C is recommended to preserve product characteristics. In order to develop a dispersive OVD that can be stored at room temperature, in this study, we searched additives which can stably maintain the viscosity, a key parameter of OVD, under preservation stability testing at 60 °C.

An In Vitro System for Evaluating Molecular Targeted Drugs Using Lung Patient-Derived Tumor Organoids.

Patient-derived tumor organoids (PDOs) represent a promising preclinical cancer model that better replicates disease, compared with traditional cell culture models. We have established PDOs from various human tumors to accurately and efficiently recapitulate the tissue architecture and function. Molecular targeted therapies with remarkable efficacy are currently in use against various tumors.

Rheological and Adhesive Properties to Identify Cohesive and Dispersive Ophthalmic Viscosurgical Devices.

The purpose of this study is to evaluate the usefulness of the rheological properties and adhesive force of ophthalmic viscosurgical devices (OVDs) as parameters for understanding and identifying the surgical behavior of cohesive and dispersive OVDs. The apparent viscosity, and the storage and loss moduli (dynamic rheological parameters) of 50% chondroitin sulfate (CS), 3% sodium hyaluronate (HA), Shellgan (the combination of 3% HA and 4% CS), Opegan (1% HA with a low molecular mass) and Opegan-Hi (1% HA with a high molecular mass) were obtained with a rheometer. The adhesive force of each sample was measured by using a texture analyzer.

Evaluation of anticancer agents using patient-derived tumor organoids characteristically similar to source tissues.

Patient-derived tumor xenograft models represent a promising preclinical cancer model that better replicates disease, compared with traditional cell culture; however, their use is low-throughput and costly. To overcome this limitation, patient-derived tumor organoids (PDOs) were established from human lung, ovarian and uterine tumor tissues, among others, to accurately and efficiently recapitulate the tissue architecture and function. PDOs were able to be cultured for >6 months, and formed cell clusters with similar morphologies to their source tumors.

Evaluation system for arrhythmogenic potential of drugs using human-induced pluripotent stem cell-derived cardiomyocytes and gene expression analysis.

In recent years, human-induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs) have been widely used to develop evaluation systems for drug cardiotoxicity, including the arrhythmia caused by QT prolongation. To accurately assess the arrhythmogenic potential of drugs, associated with QT prolongation, we developed an evaluation system using hiPS-CMs and gene expression analysis. hiPS-CMs were treated with 8 arrhythmogenic and 17 non-arrhythmogenic drugs at several concentrations for 24 hr to comprehensively analyze gene expression.

Construction of a novel cell-based assay for the evaluation of anti-EGFR drug efficacy against EGFR mutation.

Epidermal growth factor receptor (EGFR) overexpression and EGFR-mediated signaling pathway dysregulation have been observed in tumors from patients with various cancers, especially non-small cell lung cancer. Thus, several anti-EGFR drugs have been developed for cancer therapy. For patients with known EGFR activating mutations (EGFR exon 19 in-frame deletions and exon 21 L858R substitution), treatment with an EGFR tyrosine kinase inhibitor (EGFR TKI; gefitinib, erlotinib or afatinib) represents standard first-line therapy.

MUC5AC protects pancreatic cancer cells from TRAIL-induced death pathways.

We have previously reported that a specific siRNA transfected MUC5AC could knockdown MUC5AC expression and suppress in vivo tumor growth and metastasis, although it had no effects on in vitro cell growth, cell survival, proliferation and morphology. In the present study, we investigated which host immune cells induced these effects and how the effects were induced using immunocyte-depleted animal models. The tumor growth of SW1990/si-MUC5AC cells, which show no tumor growth when implanted subcutaneously into a nude mouse, was recovered when neutrophils were removed by anti-Gr-1 mAb administration.

Anti-protein-bound polysaccharide-K monoclonal antibody binds the active structure and neutralizes direct antitumor action of the compound.

Protein-bound polysaccharide K (PSK) is extracted and purified from Coriolus versicolor (CM101), and is used as an anti-cancer agent. In this study, focusing on the direct actions of PSK, we investigated whether PSK reaches tumor and immune tissues with its active structure remaining intact, and the direct action of PSK was evaluated by its antitumor effects against MethA fibrosarcomas implanted in immunodeficient NOD/SCID mice. The results obtained suggest that PSK reaches the tumor tissue in its active form and exhibits antitumor effects against MethA cells.

Tumor-associated MUC5AC stimulates in vivo tumorigenicity of human pancreatic cancer.

MUC5AC, a high molecular weight glycoprotein, is overexpressed in the ductal region of human pancreatic cancer but is not detectable in the normal pancreas, suggesting its association with disease development. In the present study, we investigated the in vitro and in vivo effects of MUC5AC knockdown by short interfering RNA (siRNA) in the MUC5AC-overexpressing SW1990 and BxPC3 human pancreatic cancer cell lines in order to clarify its function. Significant decreases in the expression levels of MUC5AC mRNA and protein were observed in SW1990 and BxPC3 cells that had been stably transfected with a MUC5AC siRNA expression vector (SW1990/si-MUC5AC and BxPC3/si-MUC5AC cells) compared to those in cells transfected with an si-mock vector (SW1990/si-mock and BxPC3/si-mock cells).

Absorption and tissue distribution of an immunomodulatory alpha-D-glucan after oral administration of Tricholoma matsutake.

Alpha-D-glucan (MPG-1) separated from Tricholoma matsutake (CM6271) has been reported to show immunomodulatory activities. In this study, the plasma concentration and tissue distribution of MPG-1 after CM6271 oral administration were investigated as part of the action mechanism analysis. When CM6271 was orally administered in a single dose to mice, MPG-1 was absorbed via the intestinal tract, appeared in plasma after 16 h, was gradually excreted from the blood, and fell to background level after 48 h.

Development of an enzyme-linked immunosorbent assay to detect an immunomodulatory alpha-D-glucan-protein complex, MPG-1, in basidiomycete Tricholoma matsutake and related processed foods.

We previously isolated a novel immunomodulatory alpha-(1,4)(1,6)(1,2)- d-glucan-protein complex (MPG-1) from mycelia of Tricholoma matsutake in basidiomycetes. In the present study, we raised a polyclonal antibody by immunizing rabbits with MPG-1 and constructed a sandwich enzyme-linked immunosorbent assay (ELISA) system to examine the distribution of MPG-1 among edible mushrooms and related processed foods. The system detected MPG-1 quantitatively at concentrations of more than 10 ng/mL, with a coefficient of variation of less than 10% by intra-assay and interassay precision.

Isolation and characterization of a novel immunomodulatory alpha-glucan-protein complex from the mycelium of Tricholoma matsutake in basidiomycetes.

Tricholoma matsutake, a high-class edible mushroom in Japan, has been reported to have excellent biological activities, but difficulty in cultivating the fruit bodies and limited bulk availability have restricted detailed studies. We have developed a method of culturing in tanks, enabling the bulk supply of the mycelia. The preparation (CM6271) exerts modulative effects on the immune competence of mice and rats.

Inhibition of decrease in natural killer cell activity in repeatedly restraint-stressed mice by a biological response modifier derived from cultured mycelia of the basidiomycete Tricholoma matsutake.

Objective: To develop a method to cope with stress-induced reduction in immunocompetence, we evaluated the immunomodulatory activities of a biological response modifier derived from the mycelia of the basidiomycete Tricholoma matsutake (CM6271) in mice under repeated restraint stress.

Methods: C57BL/6 mice were inserted, one per tube, into 50-ml polypropylene tubes into which more than 30 ventilation holes had been drilled, and were restrained everyday for 20 days in this fashion for set periods of time. Natural killer (NK) cell activity and NK1.