5-O-(4-[125 I]Iodobenzyl)-L-ascorbic acid: electrophilic radioiodination and biodistribution in mice

As a part of our efforts to develop potential imaging agents for ascorbate bioactivity, 5-O-(4-[(125)I]iodobenzyl)-L-ascorbic acid ([(125)I]1) was prepared through a two-step sequence which involved radioiodo-destannylation of a protected tributylstannyl precursor 6, followed by hydrolysis in acidic methanol of the protecting groups in 61% overall radiochemical yield, with a radiochemical purity of over 98% and a specific activity of more than 15.4?GBq/μmol. Tissue distribution of [(125)I]1 in tumor-bearing mice showed signs of distribution profiles similar to the reported results for 6-deoxy-6-[(18)F]fluoro-L-ascorbic (6-(18)FAsA) acid and 6-deoxy-6-[(131)I]iodo-L-ascorbic acid (6-(131)IAsA) but with notable differences in the adrenal glands, in which considerably lower uptake of radioactivity and rapid clearance with time were observed. Pretreatment of mice with a known inhibitor of ascorbate transport, sulfinpyrazone, did not produce any significant change in the adrenal uptake of radioactivity after injection of [(125)I]1 compared to the control, suggesting that uptake in the adrenal glands is independent of the sodium-dependent vitamin C transporter 2 transport mechanism. Introduction of a bulky substituent at C-5 on AsA, such as an iodobenzyloxy group, may not be suitable for the design of analogs that may still be able to maintain characteristic distribution properties in vivo seen with AsA itself.     

Formulation study on retinoic acid gel composed of iota-carrageenan, polyethylene oxide and Emulgen® 408

In the present study, all-trans retinoic acid (RA) gels formulated with various compositions of polyethylene oxide (Emulgen?) and iota-carrageenan (ι-CG) were prepared and their physicochemical properties were evaluated. The compression energy, which is the work required to compress the product through a fixed distance, increased with increasing amount of ι-CG or Emulgen?. The adhesion energy and displacement decreased with increasing amount of ι-CG or Emulgen? due to the progression of gel formation. From the results of the sensory tests, the properties of RA gels such as adhesiveness, gel strength and spreadability seemed to be adjustable depending on the condition of skin by varying the components of RA gels. Through photostability study, the expiration date and storage conditions of RA gels were determined as "4°C for 28?d with no exposure to light."     

Mineral composition of frozen taro for determination of geographic origin

The mineral composition of frozen food of taro [Colocasia esculenta (L.) Schott] was analyzed to categorize the geographical production place of taro. The concentrations of Co and H₂PO₄ ⁻ were found to be useful to separate the producing place between Japan and China. The analysis was performed by instrumental neutron activation analysis (INAA) and ion chromatography (IC). In the case of INAA, the samples were dried and sealed in a vinyl bag and irradiated with thermal neutrons from JRR3M, installed at Japan Atomic Energy Agency (JAEA). The activated samples were cooled down for a few weeks and the elements (Co, Cr, Fe, Rb, Zn) were determined. Cobalt concentration of frozen taro from China was higher than that from Japan. The tendency was the same in the fresh sample of taro. When concentration of H₂PO₄ ⁻ of frozen sample was measured, taro from Japanese product was higher than that of Chinese one, contrary to fresh sample. This result might be caused by the leakage of H₂PO₄ ⁻ during freezing process, indicating that we should be careful to apply the discrimination indicators. In addition to Co, there was a significant difference of Rb and Fe concentrations between frozen taro from Japan and China.     

A rigorous derivation of the bioheat equation for local tissue heat transfer based on a volume averaging theory

A general three-dimensional bioheat equation for local tissue heat transfer has been derived with less assumptions, exploiting a volume averaging theory commonly used in fluid-saturated porous media. The volume averaged energy equations obtained for the arterial blood, venous blood and tissue were combined together to form a single energy equation in terms of the tissue temperature alone. The resulting energy equation turns out to be remarkably simple as we define the effective thermal conductivity tensor, which accounts not only for the countercurrent heat exchange mechanism but also for the thermal dispersion mechanism. The present equation for local tissue heat transfer naturally reduces to the Weinbaum-Jiji equation for the unidirectional case.     

Synthesis and antibacterial activity of new 1beta-methylcarbapenems having the potential for intramolecular nonbonded S...O interactions.

Mercaptoacetyliminothiadiazoline derivatives (19, 20) useful for the pendant moiety of 1beta-methylcarbapenem antibiotics were efficiently synthesized. Acetyl derivative (18) of 20 was submitted to X-ray analysis, and a significant nonbonded S...O close contact was recognized in the crystallographic structure. New 1beta-methylcarbapenems (5, 6) were synthesized by exploiting 19 and 20, and exhibited considerable antibacterial activities in vitro.     

Ultraviolet-Laser-Induced Crystallization of Sol-Gel Derived Inorganic Oxide Films

Structural changes stimulated by ultraviolet (UV) laser irradiations of sol-gel derived inorganic oxide films were investigated. Dried gel films of TiO₂, Nb₂O₅, Ta₂O₅, SrTiO₃ and Pb(Zr _x Ti_1–x )O₃ (PZT) were found to be crystallized by the laser irradiation. On the other hand, the photo-induced change in gel films of BaTiO₃, LiNbO₃ and LiTaO₃ was not observed although the laser beams were absorbed in the films. These sol-gel films were thermally crystallized at almost the same temperature around 600–700°C except TiO₂. Thus, the UV-laser-induced crystallization is not directly ascribed to a simple thermal effect with the irradiation. Photochemical properties of the cations are assumed to be important for the change in sol-gel films.     

Finsler Hardy inequalities

In this paper we present a unified simple approach to anisotropic Hardy inequalities in various settings. We consider Hardy inequalities which involve a Finsler distance from a point or from the boundary of a domain. The sharpness and the non-attainability of the constants in the inequalities are also proved.     

Coulomb and strong interactions for Bose-Einstein correlations

We present an analytical formula for the Bose-Einstein correlations (BEC) which includes effects of both Coulomb and strong final state interactions (FSI). It was obtained by using Coulomb wave function together with the scattering partial wave amplitude of the strong interactions describing data on thes-wave phase shift. We have proved numerically that this method is equivalent to solving Schrödinger equation with Coulomb and thes-wave strong interaction potentials. As an application we have analysed, using our formula which includes the degree of coherence and the long range correlation, the data fore ⁺ e ^? annihilations. We have found that the degree of coherence present in our formula approaches approximately unity whereas the long range correlation parameter becomes approximately zero. These results suggest that the physical meanings of the fractional degree of coherence and the long range correlation observed in various other analyses can most probably be attributed to FSI.     

Morphology control of polypropylene by crystallization under carbon dioxide

We investigated the crystalline morphology of isotactic polypropylene obtained by melt crystallization under carbon dioxide (CO₂) at various pressures. Spherulites consisting of regularly arranged fibrils without subsidiary lamellae were obtained by crystallization under CO₂ below 2 MPa, whereas large spherulites consisting of irregularly arranged fibrils with subsidiary lamellae were obtained under ambient pressure. Distorted domain crystals with uniform optical anisotropy consisting of α‐form were found to be obtained under CO₂ above 2 MPa, and needle crystals consisting of γ‐form were obtained above 12 MPa. Transmission electron micrographs showed that straight and thick lamellae are regularly arranged in both the distorted domain crystals and the needle crystals. The uniformly thick lamellae were confirmed by differential scanning calorimetry thermograms; that is, the melting temperature is higher and the melting peak is sharper than those obtained under ambient pressure. Such characteristic crystalline morphologies obtained under CO₂ may be attributed to local ordering in the melt state. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2738–2746, 2004