Application of neutron capture autoradiography to Boron Delivery seeking techniques for selective accumulation of boron compounds to tumor with intra-arterial administration of boron entrapped water-in-oil-in-water emulsion

It isnecessary to accumulate the 10B atoms selectively to the tumor cells for effective Boron Neutron Capture Therapy(BNCT). In order to achieve anaccurate measurement of 10B accumulations in the biological samples, we employed a technique of neutron capture autoradiography (NCAR) of sliced samples of tumor tissues using CR-39 plastic track detectors. The CR-39 track detectors attached with the biological samples were exposed to thermal neutrons in the thermal column of the JRR3 of Japan Atomic Energy Agency (JAEA). We obtained quantitative NCAR images of the samples for VX-2 tumor in rabbit liver after injection of 10BSH entrapped water-in-oil-in-water (WOW) emulsion by intra-arterial injection via proper hepatic artery. The 10B accumulations and distributions in VX-2 tumor and normal liver of rabbit were investigated by means of alpha-track density measurements. In this study, we showed the selective accumulation of 10B atoms in the VX-2 tumor by intra-arterial injection of 10B entrapped WOW emulsion until 3 days after injection by using digitized NCARimages (i.e.alpha-track mapping)

Fast Response, High‐Power Tunable Ultrathin Soft Actuator by Functional Piezoelectric Material Composite for Haptic Device Application

Abstract Recently, self‐driven soft robotics based on biomimetics, capable of mimicking biological motion, has attracted attention. Soft actuators using intrinsically soft organic materials are expected to be applied to haptic devices, artificial muscles, and micropumps. Ferroelectric polymers can aid in the realization of such soft actuators. However, actuators using such materials encounter problems in terms of the response frequency to an applied voltage. In this study, a soft actuator is fabricated by a printing process using a unique composite material comprising P(VDF‐TrFE), nano‐carbon material (single‐walled carbon nanotubes (SWCNT) and graphene oxide (GO)), and conductive polymer. To characterize the actuator using a minimum substrate thickness of 25 µm, hysteresis curves in the ferroelectric properties and driving characteristics according to the applied frequency are clarified. In addition, the mechanical life of the actuator under continuous voltage sweep is clarified considering it as a mechanical property. Subsequently, a simple haptics system is constructed using the fabricated actuators, and a human‐sensitive actuator demonstration system is constructed wherein the phase of the sweep frequency is variable

Biosynthesis of Drug Glucuronide Metabolites in the Budding Yeast <i>Saccharomyces cerevisiae</i>

Glucuronidation is one of the most common pathways in mammals for detoxification and elimination of hydrophobic xenobiotic compounds, including many drugs. Metabolites, however, can form active or toxic compounds, such as acyl glucuronides, and their safety assessment is often needed. The absence of efficient means for <i>in vitro</i> synthesis of correct glucuronide metabolites frequently limits such toxicological analyses. To overcome this hurdle we have developed a new approach, the essence of which is a coexpression system containing a human, or another mammalian UDP-glucuronosyltransferases (UGTs), as well as UDP-glucose-6-dehydrogenase (UGDH), within the budding yeast, <i>Saccharomyces cerevisiae</i>. The system was first tested using resting yeast cells coexpressing UGDH and human UGT1A6, 7-hydroxycoumarin as the substrate, in a reaction medium containing 8% glucose, serving as a source of UDP-glucuronic acid. Glucuronides were readily formed and recovered from the medium. Subsequently, by selecting suitable mammalian UGT enzyme for the coexpression system we could obtain the desired glucuronides of various compounds, including molecules with multiple conjugation sites and acyl glucuronides of several carboxylic acid containing drugs, namely, mefenamic acid, flufenamic acid, and zomepirac. In conclusion, a new and flexible yeast system with mammalian UGTs has been developed that exhibits a capacity for efficient production of various glucuronides, including acyl glucuronides