Emission image of X-ray-irradiated CR-39 stick doped with methylviologen-encapsulated silica nanocapsules using LED light

Progress in Nuclear Science and Technology


L-histidine augments the oxidative damage against Gram-negative bacteria by hydrogen peroxide

Excessive damage to DNA and lipid membranes by reactive oxygen species reduces the viability of bacteria. In the present study, the proliferation of recA-deficient Escherichia coli strains was revealed to be inhibited by 1% L-histidine under aerobic conditions. This inhibition of proliferation was not observed under anaerobic conditions, indicating that L-histidine enhances oxidative DNA damage to E. coli cells. Reverse transcription-quantitative polymerase chain reaction analysis demonstrated that the expression of recA in E. coli MG1655 increased ~7-fold following treatment with 10 mM hydrogen peroxide (H2O2) plus 1% L-histidine, compared with that following exposure to H2O2 alone. L-histidine increased the genomic fragmentation of E. coli MG1655 following exposure to H2O2. In addition, L-histidine increased the generation of intracellular hydroxyl radicals in the presence of H2O2 in E. coli cells. Next, our group investigated the disinfection properties of the H2O2 and L-histidine combination. The combination of 100 mM H2O2 and 1.0% L-histidine significantly reduced the number of viable cells of extended-spectrum-β-lactamase-producing E. coli and multidrug-resistant Pseudomonas aeruginosa, and this treatment was more effective than 100 mM H2O2 alone, but this effect was not observed in methicillin-resistant Staphylococcus aureus or vancomycin-resistant Enterococcus faecium. The combination of L-histidine and H2O2 may be a useful strategy to selectively increase the microbicidal activity of oxidative agents against Gram-negative bacteria.

International Journal of Molecular Medicine


Preparation of new scintillation imaging material composed of scintillator-silica fine powders and its imaging of tritium

A new scintillation imaging material [scintillator-silica fine powder (FP)] was prepared using silica FPs and scintillator-encapsulating silica nanoparticles (NPs) (scintillator-silica NPs). The wt% values of scintillator-silica NPs on the scintillator-silica FPs were 38, 43, 36 and 44%. Scintillation images of 3H, 63Ni, 35S, 33P, 204Tl, 89Sr and 32P dropped on the scintillator-silica FPs were obtained at about 37 kBq per 0.1-10 µl with a charge-coupled device (CCD) imager for a 5 min exposure. In particular, high-intensity CCD images of 35S were selectively obtained using the 2.25, 4.77 and 10 µm silica FPs with scintillator-silica NPs owing to the residual S of dimethyl sulfoxide in the preparation. Scintillation images of 3H at 1670 ± 9 Bq/0.5 µl and 347 ± 6 Bq/0.5 µl dropped in a 2 mm hole on the scintillator-silica FPs (6.78 and 10 µm) were also obtained using the CCD imager for a 2 h exposure.


Visualization of PVDF nanofibers coated on filter paper using fluorescein silica nanoparticles


Enhancement of counting efciency for tritium using light-excited scintillator silica pellets

Journal of Radioanalytical and Nuclear Chemistry


Scintillation imaging of tritium radioactivity distribution during tritiated thymidine uptake by PC12 cells using a melt-on scintillator

A scintillation image of tritium fixed in a melt-on scintillator was obtained using a charged-coupled device (CCD) imager, and a linear relationship was observed between the intensity of the scintillation image and the radioactivity of tritium. In a [(3)H]thymidine uptake experiment, a linear correlation between the intensity of the CCD image and the dilution ratio of cells was confirmed. Scintillation imaging has the potential for use in direct observation of tritium radioactivity distribution.


Reversible radiochromic plate based on polyvinyl alcohol-iodide complex containing silica nanoparticles


Optical property of CR-39 synthesized by doping with methylviologen-encapsulated SiO2 nanocapsules as a solid-state X-ray plate detector


Silica-nanocapsule-doped CR-39 for fluorescence detection of Xrays


Simultaneous Measurement of Dispersal and Adhesion Rates of Tritium using Filter Paper and a Model Room

モデルルームとろ紙を用いたトリチウムの空気中飛散率と壁面付着率の同時測定

Tritium dispersal rate in the air and adhesion rate on the wall from a 3H-ATP aqueous solution were simultaneously measured using a model room having six pieces of filter paper attached on the wall. A distribution of tritium on each wall was obtained from the radioactivity of each filter paper divided into 9 pieces. During an exposure time of 2 h to 24 h both dispersal and adhesion rates indicated a similar behavior. With the passage time from the purchase until 13 months both dispersal and adhesion rates linearly increased and it was found that about 0.15% per one month increased as the total rates of dispersal and adhesion.

Japanese Journal of Radiation Safety Management

日本放射線安全管理学会誌


Utility of respiratory-gated small-animal PET/CT in the chronologic evaluation of an orthotopic lung cancer transplantation mouse model.

Our aim in this study was to clarify the effects of respiratory-gated PET in the evaluation of lung cancer according to the (18)F-FDG uptake in an orthotopic transplantation mouse model. We created such a model, and we performed PET/CT. The mice were divided into two groups according to tumor volume: a small-tumor group (<20 mm(3)) and a large-tumor group (>20 mm(3)). We reconstructed the following conditions based on list-mode data: non-gated (3D) images and gated (4D) images, divided based on the respiratory cycle (expiration phase, stable phase, and inspiration phase). We calculated the maximum standardized uptake values (SUVmax) in each phase. We used the % difference [= (4D SUVmax - 3D SUVmax)/3D PET SUVmax × 100 (%)] to evaluate the differences in the 4D SUVmax and 3D SUVmax. The 4D SUVmax values were significantly higher than the 3D SUVmax, regardless of the tumor size. The % difference for the small tumors was greater than that for the large tumors, and it was highest in the stable phase. We conclude that the SUVmax in the stable phase under respiratory-gated PET are the most reliable. The SUVmax observed under non-gated PET are considered to be more frequently underestimated in cases involving small tumors than in those involving large tumors. In the chronologic study evaluating the time course of tumor development, the size of the tumor is small in early stage, and respiratory-gated PET is effective in reducing the underestimation of such tumors caused by respiratory motion.


メルトオンシンチレータを用いたトリチウム放射能の画像化

メルトオンシンチレータを用いたトリチウム放射能の画像化

日本放射線安全管理学会誌


In situ 18F-gamma-ray induced Ag nanoparticle formation in the presence of SiO2 nanoparticles under air


Decontamination of radioactivity from contaminated vegetables derived from the Fukushima nuclear accident


VCAM-1-targeted core/shell nanoparticles for selective adhesion and delivery to endothelial cells with lipopolysaccharide-induced inflammation under shear flow and cellular magnetic resonance imaging in vitro

Multifunctional nanomaterials with unique magnetic and luminescent properties have broad potential in biological applications. Because of the overexpression of vascular cell adhesion molecule-1 (VCAM-1) receptors in inflammatory endothelial cells as compared with normal endothelial cells, an anti-VCAM-1 monoclonal antibody can be used as a targeting ligand. Herein we describe the development of multifunctional core-shell Fe(3)O(4)@SiO2 nanoparticles with the ability to target inflammatory endothelial cells via VCAM-1, magnetism, and fluorescence imaging, with efficient magnetic resonance imaging contrast characteristics. Superparamagnetic iron oxide and fluorescein isothiocyanate (FITC) were loaded successfully inside the nanoparticle core and the silica shell, respectively, creating VCAM-1-targeted Fe(3)O(4)@SiO2(FITC) nanoparticles that were characterized by scanning electron microscopy, transmission electron microscopy, fluorescence spectrometry, zeta potential assay, and fluorescence microscopy. The VCAM-1-targeted Fe(3)O(4)@SiO2(FITC) nanoparticles typically had a diameter of 355 ± 37 nm, showed superparamagnetic behavior at room temperature, and cumulative and targeted adhesion to an inflammatory subline of human umbilical vein endothelial cells (HUVEC-CS) activated by lipopolysaccharide. Further, our data show that adhesion of VCAM-1-targeted Fe(3)O(4)@SiO2(FITC) nanoparticles to inflammatory HUVEC-CS depended on both shear stress and duration of exposure to stress. Analysis of internalization into HUVEC-CS showed that the efficiency of delivery of VCAM-1-targeted Fe(3)O(4)@SiO2(FITC) nanoparticles was also significantly greater than that of nontargeted Fe(3)O(4)@SiO2(FITC)-NH2 nanoparticles. Magnetic resonance images showed that the superparamagnetic iron oxide cores of the VCAM-1-targeted Fe(3)O(4)@SiO2(FITC) nanoparticles could also act as a contrast agent for magnetic resonance imaging. Taken together, the cumulative adhesion and uptake potential of these VCAM-1-targeted Fe(3)O(4)@SiO2(FITC) nanoparticles targeted to inflammatory endothelial cells could be used in the transfer of therapeutic drugs/genes into these cells or for diagnosis of vascular disease at the molecular and cellular levels in the future.


Proposal of an experiment of the cloud chamber using the diagnostic X-ray apparatus and an analysis assisted by the simulation code

診断用X線装置を用いた霧箱実験の提案とシミュレーションコードを援用した解析

A cloud chamber is a radiation detector that can visualize the tracks of charged particles. In this study, we developed a middle-type cloud chamber for use in practical training using a diagnostic X-ray apparatus. Because our cloud chamber has a heater to vaporize ethanol and features antifogging glass, it is possible to observe the vapor trails for a long time without the need for fine adjustments. X-rays with a tube voltage of 40 kV or of 120 kV (with a 21-mm aluminum filter) were irradiated at the chamber and the various phenomena were observed. We explain these phenomena in terms of the range of electrons and/or interactions between X-rays and matter and conclude that our analysis is consistent with analysis using the Monte Carlo simulation code EGS5.

Japanese Journal of Radiological Technology


Preparation of Paper Scintillator for Detecting 3H Contaminant


Removal of radioactive iodine and cesium species from rainwater by a pot-type water purifier and chemical and physical analysis of radioactive components in rainwater

A pot-type water purifier captured 98% of the nonradioactive iodine and iodide when an ion-exchange resin and activated carbon were used. Approximately 93.8% of 131I, 74 to 84.5% of 134Cs, and 75 to 81.1% of 137Cs in rainwater were captured after six repeated purifications using the purifier. The remaining 6.2% of 131I was not removed by isotope exchange with nonradioactive I- or by reduction to I- using Na2S2O4. Approximately 19% of 131I, 40% of 134Cs, and 33% of 137Cs were adsorbed on the silica gel. Analysis of the removal rates of 73% for the mixed ion exchange resin, 59% for the silver ions, and 18% for the silver nanoparticle-bound clay indicated that the content of 131I adsorbed particles components was 23%. The concentration ratio of radioactive components in rainwater decreased from 5.9 to 1.4 upon ultrafiltration with a YM-1 membrane filter, indicating that a soft aggregation of the aerosol occurred. The IP and γ-ray spectrum analysis of the filter produced a cottonlike image of 131I. Analysis of the TEM image and its electron diffraction pattern indicated the aggregation of a small fraction of the SiO2 aerosol. The coagulation of radioactive components in rainwater using I-adsorbed SiO2 nanoparticles may be due to the exchange of the 131I isotope with I in I-SiO2 and the adsorption of 134Cs+ and 137Cs+ on the surface of SiO2 or the precipitation of the 131I-adsorbed aerosol and 134Cs- and 137Cs-adsorbed aerosols.


Separation of radioactive cesium and iodine from contaminated soil by adsorption and decantation

Approximately 19% of 131I was released in a solution mixing contaminated soil with distilled water and 10 wt% CaCl2 solution, and the remaining 131I tightly bound to the soil. Approximately 12 to 15% of the radioactive cesium was found in the supernatant after mixing with saturated KCl aqueous solution, and the repeated treatment for 1 day indicated the additional release of 11 to 15% in the supernatant. Approximately 15 to 20% of radioactive cesium was found in the supernatant by mixing with saturated KCl solution and KCl powder, followed by heating. The repeated treatment with 40% KI solution led to a maximum release rate of 66% of radioactive cesium from the soil.


γ-Ray Induced Catalytic Properties of the Silica Nanoparticles Dispersed in the Aerated Aqueous Solution

Journal of Radioanalytical and Nuclear Chemistry


Decontamination of radioactive-iodine- and cesium-contaminated spinach using sodium dithionite

Washing of the spinach with water by the Nishizawa method resulted in the removal of about 13 ± 2% of the 131I and 45 ± 20% of the 134Cs and 137Cs. Removal rates of 131I of approximately 76 ± 3% after further washing with 1.2 wt% Na2S2O4 for 2 days and 47 ± 2% washing with 10 wt% Na2S2O4 for 2 days were obtained. These values agreed with the dissolution rates of 131I in the liquid used for washing within 2 to 3% error. The removal rates of 134Cs and 137Cs after washing with 1.2 wt% Na2S2O4 for 2 days were 69 ± 47% and 100 ± 52%, respectively, which were in poor agreement with the corresponding dissolution rates. The removal rate of 131I after brief washing with 10 wt% Na2S2O4 was negligible and the dissolution rate was 5 ± 2%. The removal rates of 134Cs and 137Cs for 10 wt% Na2S2O4 increased from 26 ± 11% to 42 ± 11% and from 30±20% to 42 ± 20% after washing with Na2S2O4 for 2 days. The high removal rates in 1.2 wt% Na2S2O4 may be due to the effective reduction of the I2 on the surface of the leaves by Na2S2O4 (1.2 wt%) during the 2 day immersion, which occurred without the bleaching of the leaves and stalks, which occurred in the case of 10 wt% Na2S2O4.


Estimation of activities caused by black spots for digital radiography system --- Analysis of black spots by the low concentrate radioisotopes adhered directly to the surface of the phosphor plate

Digital radiographyシステムで発生した黒点の放射能の推定 --- 輝尽性蛍光体板表面に直接付着した低濃度放射性同位元素起源の黒点の解析

Because of an accident of the nuclear power plants in the Fukushima, many radioisotopes (RI) have been diffused to the environment. As a result, black spots were appearing on the medical images which were taken by the phosphor plate. The aim of this study is to evaluate the activity (Bq) of radioactive contaminated IP based on the experiment using RI. The radioactive material (134Cs and/or 137Cs) in the form of liquid was dropped on filter paper (25 mm2), and radioactive sources having 40 240 Bq activities were made. These sources were closely attached to the IP with irradiation times of 2 22 h. Then, we obtained the relationship between pixel values and products of activities and irradiation times. Using these relationships, we evaluated the activity in the contaminated IP. The evaluated value of approximately 7 Bq was in good agreement with a value which was inhered in a chemical wiper used for the decontamination of the IP. Based on the results, we summarized that almost all black spots were created by the RI adhered directly to the IP.


Chemical removal of radionuclides in contaminated spinach derived from the Fukushima nuclear accident

We examined a simple and effective removal method for contaminated farm products to ensure the relief of farmers and the security of consumers. Removal of radionuclides from spinach by chemical methods was investigated. The result of chemical removal showed that antioxidant agents removed radionuclides from spinach by 70-80% for 131I and more than 80% for radiocesium. In particular, ascorbic acid is promising as a safe and versatile option.


Improvement of an X-ray Diffraction Equipment for the X-ray Safety Education

X線取扱者の安全教育のためのX線結晶回折装置の改良


Photoinduced Electron Accumulation of Titanium Dioxide Nanoparticle Modified Electrodes

International Journal of Modern Physics: Conference Series


Whole-Body Distribution of 14C-labeled Silica Nanoparticles and Submicron Particles after Intravenous Injection into Mice


ICRマウスにおける44nm14C標識シリカナノ粒子を用いた体内動態評価モデルの構築

土木学会論文集G(環境)

土木学会論文集G(環境)


Properties of signal intensities observed with individual probes of GeneChip Rat Gene 1.0 ST Array, an affymetric microarray system.

For proper evaluation of the results of microarray experiments, it is important to understand how the signal intensities of individual probes are determined. Our previous studies revealed that signal intensities of individual probes in the Agilent array system (code G4131F) are largely dependent upon the location of the probes in the mRNA. In the present study, we examined the properties of signal intensities of individual probes in an Affymetrix array system (GeneChip Rat Gene 1.0 ST Array), in which a random primer fused to the T7 promoter sequence is employed. Distinct from the Agilent array system, individual probes used in this Affymetrix array system did not show the probe-location effects, but gave relatively diverse signal intensities. However, the diversities of the signal intensities of these individual probes were not due to experimental error.


Investigation of folate-conjugated fluorescent silica nanoparticles for targeting delivery to folate receptor-positive tumors and their internalization mechanism

Multifunctionalized nanoparticles (NPs) are emerging as ideal tools for gene/drug delivery, bioimaging, labeling, or intracellular tracking in biomedical applications, and have attracted considerable attention owing to their unique advantages. In this study, fluorescent silica NPs were synthesized by a modified Stöber method using conjugates of 3-mercaptopropyltrimethoxysilane (MPS) and maleimide-fluorescein isothiocyanate (maleimide-FITC). Mean diameters of the NPs were controlled between 212-2111 nm by regulating MPS concentration in the reaction mixture. Maleimide-FITC molecules were doped into NPs or conjugated to the surface of NPs through the chemical reaction of maleimide and thiol groups. The data showed that the former NPs are better than the latter by comparing their fluorescence intensity. Furthermore, folate molecules were linked to the FITC-doped silica NPs by using polyethylene glycol (PEG) (NH2-PEG-maleimide) as a spacer, thus forming folate receptor targeting fluorescent NPs, referred to as NPs(FITC)-PEG-Folate. The quantitative analysis of cellular internalization into different cancer cells showed that the delivery efficiency of KB cells (folate receptor-positive cells) is more than six-fold higher than that of A549 cells (folate receptor-negative cells). The delivery efficiency of KB cells decreased significantly after free folate addition to the cell culture medium because the folate receptors were occupied by the free folate. The NPs endocytosis mechanism was also investigated. It was shown that clathrin, an inhibitor of cell phagocytosis, markedly decreased the NPs uptake into KB cells, suggesting that it plays an important role in NPs cellular internalization. These results demonstrated that the novel particles of NPs(FITC)-PEG-Folate are promising for fluorescent imaging or targeting delivery to folate receptor-positive tumors.


Core/Shell Fe3O4 @ SiO2 Nanoparticles Modified with PAH as a Vector for EGFP Plasmid DNA Delivery into Hela Cells

Novel stable core/shell Fe(3)O(4)@SiO(2)/PAH nanoparticles are synthesized using 15 nm Fe(3)O(4) as the template that is modified with PAH. The resulting nanoparticles can absorb plasmid DNA to mediate gene transfer in cultured HeLa cells. An electrophoretic assay suggests that the Fe(3)O(4)@SiO(2)/PAH nanoparticles protect the plasmid DNA from serum and DNase I degradation. A cell viability assay shows that the Fe(3)O(4)@SiO(2)/PAH nanoparticles exhibit a low cytotoxicity toward endothelial cells. Qualitative analysis of transfection in HeLa cells by nanoparticles carrying a plasmid DNA encoding EGFP demonstrates a fairly high expression level, even in the presence of serum. Thus, Fe(3)O(4)@SiO(2)/PAH nanoparticles are biocompatible and suitable for nonviral delivery, and may find applications in cancer therapy.


Preparation of 3H-ATP-incorporated silica nanoparticles and its diffusive release


Novel Accumulation of Photo-Induced MV+ Embedded in a TiO2 Shell and Discharge of Electrons to a Pt Electrode

After UV-irradiation of a TiO(2) shell on Pt anode was cut off, anodic current was observed continuously for some time because long-lived MV(+)* produced from MV(2+) embedded inside the shell, as a result of the electron transfer from the conduction band of the irradiated TiO(2) shell, diffused slowly and discharged to the shell thus realizing electron accumulation inside the TiO(2) shell.


Characterization and photochemical and antibacterial properties of highly stable silver nanoparticles prepared on montmorillonite clay in n-hexanol

Ag nanoparticles (NPs) of approximately 2.5±0.6nm in size with high stability were prepared on montmorillonite clay in n-hexanol ([Ag NP/clay]). The aqueous suspensions of Ag NP/clay obtained were colored pale yellow to gray, and an intense yellow surface plasmon band was observed at approximately 397-422nm at a [Ag(+)] concentration of 0.01-1M. Fluorescence peaks of these Ag NP/clay suspensions, which were due to interband transitions of Ag NPs, were observed at approximately 447nm upon excitation at approximately 341nm. Photoinduced charge separation and electron accumulation in the presence of 2-propanol were observed in the Ag NPs on the clay. The photogenerated holes indicate a reaction with OH(-) because the generation of ()OH radicals decreased in the presence of 2-propanol, as observed using a spin-trapping electron spin resonance (ESR) method. The amount of H(2) produced depended on the amount of Ag NPs on the clay and the concentration of 2-propanol in the suspension. Antibacterial activity of Ag NPs on clay was also observed against Escherichia coli even after 12years. This simple method of preparation in n-hexanol led to the successful formation of highly stable and photoactive Ag NPs on montmorillonite clay.

Journal of Colloid and Interface Science


Vascular gene transfer and drug delivery in vitro using low-frequency ultrasound and microbubbles

To determine the effects of ultrasound exposure in combination with a microbubble contrast agent (SonoVue) on the cellular uptake and delivery of drugs/genes into human umbilical vein endothelial cells (HUVECs) as well as their biological effects on migration. HUVECs in suspension were exposed to pulsed ultrasound with a 10% duty cycle in combination with various concentrations of a microbubble contrast agent (SonoVue) using a digital sonifier at a frequency of 20 kHz and an intensity of 3.77 W/cm(2) on the surface of a horn tip. Cell culture inserts were used to determine the cell migration ability. Exposure to pulsed ultrasound resulted in enhanced green fluorescent protein (EGFP) gene transfection efficiencies ranging from 0.2% to 2%. The transfection efficiency of HUVECs was approximately 3-fold higher in the presence of SonoVue than in its absence at the effective exposure time of 6 s. For drug delivery to HUVECs using ultrasound, the delivery efficiencies of a low-molecular-weight model drug (TO-PRO-1, M(W) 645.38) were significantly higher when compared to drug delivery without ultrasound, with a maximum efficiency of approximately 34%. However, the delivery efficiencies of a high-molecular-weight model drug (Dextran-Rhodamine B, M(W) 70,000) were low, with a maximum delivery efficiency of nearly 0.5%, and gene transfection results were similarly poor. The migration ability of HUVECs exposed to ultrasound was also lower than that of the control (no exposure). The use of low-frequency and low-energy ultrasound in combination with microbubbles could be a potent physical method of increasing drug/gene delivery efficiency. This technique is a promising nonviral approach that can be used in cardiovascular disease therapy.


Preparation, characterization and release of methyl viologen from a novel nanoparticle delivery system with double shells of silica and PLGA


Control of emission peaks of X-ray phosphor using dye-silica nanoparticles


Behavior of fluorescent molecules bound to the interior of silica nanoparticles in various solvents

Porous silica nanocapsules with 20% 3-aminopropyltrimethoxysilane (APS)-bound 6-carboxy-fluorescein (APS-fluorescein) and 80% APS molecules adsorbed on the surface of a 50-nm-diameter Au core were prepared by a modified core-shell method. Silica mesoporous nanocapsules were obtained after the Au cores were dissolved in sodium cyanide. The size of the pores in the silica shells corresponded to the area of the fluorescein (approximately 1.02 nm(2)) in each APS-fluorescein molecule, which was bound to the silica shell by coupling between the silanol groups of APS in the APS-fluorescein molecule and the silica shell. The amino group of APS bound to the silica inside the shell is also reactive. Dy485XL N-hydroxysuccinimide ester (NHS) molecules were then added to the mesoporous silica nanocapsules in the solution and bonded to the amino group of the interior. Thus, mesoporous (fluorescein and Dy485XL)-bound silica nanocapsules were obtained. The fluorescence of Dy485XL was only observed in the mesoporous (fluorescein and Dy485XL)-bound silica nanocapsules in aqueous solution after ultrafiltration. However, the fluorescence of fluorescein reappeared after the addition of acetonitrile. Furthermore, upon adding various solvents to the mesoporous (fluorescein and Dy485XL)-bound silica nanocapsules, their fluorescence varied with that of fluorescein or Dy485XL. In the case of a mixture of 6-carboxy-fluorescein-N-hydroxysuccinimide (FLUOS) and Dy485XL-NHS free molecules in aqueous solution, the fluorescence of FLUOS was observed. Such different fluorescence phenomena demonstrated that Dy485XL-NHS molecules can easily penetrate into the nanocapsule interior via the pores and that the interior of the silica nanocapsules can bind to Dy485XL molecules. These fluorescence behaviors are discussed in terms of fluorescence resonance energy transfer (FRET) and solvatochromism.


Poly(D,L-lactide-co-glycolide) Nanoparticles Encapsulated Fluorescent Isothiocyanate and Paclitaxol: Preparation, Release Kinetics and Anticancer Effect

Poly(D,L-lactide-co-glycolide) (PLGA) is a biodegradable and biocompatible polymer material for drug deliver system. The aim of this study is to synthesize drug-loaded PLGA nanoparticles for sustained release and its anticancer effect in vitro. PLGA nanoparticles were prepared with modified solvent evaporation method. PLGA nanoparticles encapsulated fluorescent isothiocyanate (FITC, as a model drug) and paclitaxol (therapeutic drug) were prepared with the diameter of within 800 nm as drug carrier. The release kinetics and anticancer effect for HeLa cells of the PLGA nanoparticles were further investigated. There was a peak of accumulative FITC release from the FITC-loaded PLGA nanoparticles at approximate 18 h. The inhibition rate of HeLa cell growth was studied by 3-(4,5-dimethylthiazol-2-yl)-3,5-diphenyltetrazolium (MTT) colorimetric assay. Cells were killed by paclitaxol-loaded PLGA nanoparticles. Apoptosis of HeLa cells maybe also occurred due to the sustained release of paclitaxol from the PLGA nanoparticles, which showed that PLGA nanoparticles encapsulated paclitaxol are promising as a controlled drug delivery system in future clinic application.

Journal of Nanoscience and Nanotechnology


Measurement of Spread of Tritium Using the Tritium Labeled Compound

トリチウム標識化合物を用いたトリチウム飛散測定

Japanese Journal of Radiation Safety Management

日本放射線安全管理学会誌


Preparation and Characterization of Novel Drug Delivery System of Light-Sensitive Silica Nanocapsules with Thin Shells


Nanomedicine for drug delivery and imaging: a promising avenue for cancer therapy and diagnosis by targeted functional nanoparticles

The diagnosis and treatment of cancer or tumor at the cellular level will be greatly improved with the development of techniques that enable the delivery of analyte probes and therapeutic agents into cells and cellular compartments. Organic and inorganic nanoparticles that interface with biological systems have recently attracted widespread interest in the fields of biology and medicine. The new term nanomedicine has been used recently. Nanoparticles are considered to have the potential as novel intravascular or cellular probes for both diagnostic (imaging) and therapeutic purposes (drug/gene delivery), which is expected to generate innovations and play a critical role in medicine. Target-specific drug/gene delivery and early diagnosis in cancer treatment is one of the priority research areas in which nanomedicine will play a vital role. Some recent breakthroughs in this field recently also proved this trend. Nanoparticles for drug delivery and imaging have gradually been developed as new modalities for cancer therapy and diagnosis. In this article, we review the significance and recent advances of gene/drug delivery to cancer cells, and the molecular imaging and diagnosis of cancer by targeted functional nanoparticles.


Novel drug delivery system of hollow mesoporous silica nanocapsules with thin shells: Preparation and fluorescein isothiocyanate (FITC) release kinetics.

Core-shell nanoparticles of Au@silica with a diameter of approximate 45-60 nm and wall thickness in range of 3-10 nm were synthesized by using 40 and 50 nm gold nanoparticles as the templates. The mesoporous particles are regulated by 3-aminopropyltrimethoxysilane addition. Hollow mesoporous silica nanocapsules (HMSNs) were prepared by using sodium cyanide to dissolve the gold cores. The characterization of Au@silica and HMSNs by transmission electronic microscope indicated that the silica shells were uniform and smooth, and also the porosity was proved by fluorescein isothiocyanate (FITC) release experiments. The ratio of hollow core to HMSNs is more than 70%. HMSNs were subsequently used as drug carrier to investigate FITC (as a model drug) release behaviors in vitro. Fluorescent spectrometry was performed to determine the release kinetics from the HMSNs. The release profiles are significantly different as compared with the control (free FITC), which show that HMSNs are good drug carriers to control drug release, and have high potential in therapeutic drugs delivery in future applications.


教育訓練受講時期の教育効果に与える影響と再教育訓練内容の検討

教育訓練受講時期の教育効果に与える影響と再教育訓練内容の検討

日本放射線安全管理学会誌


教育訓練の受講回数とRI使用の有無の教育効果へ与える影響

教育訓練の受講回数とRI使用の有無の教育効果へ与える影響

日本放射線安全管理学会誌


銀担持アクリル繊維を含む抗菌紙の殺菌作用機構

銀担持アクリル繊維を含む抗菌紙の殺菌作用機構

銀担持アクリル繊維とポリエステル繊維から作製したiziの抗菌特性と殺菌作用機構を検討した．iziは，病原性細菌，Legionella pneumophila Sg1 IID 5232などを含む13菌株に対して広く高い抗菌スペクトルを示した．iziの殺菌力は，食塩，ペプトン共存下で低下することを認めた．iziの殺菌化学種は，電子スピン共鳴スペクトルと，スーパーオキシドジスムターゼもしくはヨウ化カリウムのようなラジカルスカベンジャーにより活性阻害が起こることから，ヒドロキシラジカルであることを証明し，細菌細胞中で変換されたリビングラジカルが，継続的な殺菌効果を示すことを示唆した．また，細菌細胞が，iziから銀イオンを引き抜くことを示唆した．

Journal of Antibacterial and Antifungal Agents, Japan


Patient Skin Dose in Interventional Radiology Using Radiochromic Dosimetry Film

反射型線量測定用フィルムを用いたIVR手技時の患者皮膚線量

照射部位が多彩で，X線管-皮膚間距離が不定なIVR手技に対してX線照射により直ちに発色する感材で作られた低感度の反射型フィルムを用いた被曝線量測定について検討した結果，良好な結果が得られたので報告した．

Japanese Journal of Radiological Technology


X線により発色をする反射型フィルム素材を用いたIVR手技時の患者皮膚線量測定

X線により発色をする反射型フィルム素材を用いたIVR手技時の患者皮膚線量測定


Visible Light-Induced Bactericidal Species Generated From Silver-Loaded Hydrogen Zirconium Phosphate Active Against Escherichia coli K12

論文題目:銀担持リン酸水素ジルコニウムからの可視光で誘導される殺菌化学種，可視光照射された銀水素リン酸ジルコニウム懸濁液から生成するOHラジカルは，スピントラップ剤であるDMPOの添加によってESRで観測することができた．I-の存在下では，DMPO-OHのピークは減少してI2が生成し，それに伴って大腸菌に対して抗菌作用を示した．エタノールや2-プロパノールの存在下では，OH•と反応して生成するアルコールラジカルが，OH•よりも高い抗菌活性を示すことを明らかにした．


X線フィルムにおけるクロスオーバ効果の増感紙からの発光波長依存性

X線フィルムにおけるクロスオーバ効果の増感紙からの発光波長依存性


Clinical Investigation of Accumulation Process of 99mTc-HMDP and -MDP in Bone

99m-Tc-HMDPおよび-MDPの骨への集積過程の臨床的研究


Neuronal impairment of adult moyamoya disease detected by quantified proton MRS and comarison with cerebral perfusion by SPECT with Tc-99m HM-PAO: A trial of clinical quantification of metabolites

We evaluated neuronal impairment of adult moyamoya patients by proton magnetic resonance spectroscopy (MRS) and cerebral perfusion scintigraphy. After evaluating two methods for compensating relaxation times, we selected a long TR, short TE sequence to achieve better reproducibility. The cerebral blood flow (CBF) value was measured by scintigraphy following the method of quantification reported in the previous literature. N-acetyl aspartate (NAA) concentrations and CBFs value were decreased statistically (P < 0. 05) compared with those of the age-matched normal controls. However, the decreased rate of NAA concentration was changed more than the CBF value, and no linear correlation was found between the two values. We considered that the NAA concentration was not always correlated with that of the present cerebral perfusion. The NAA concentration showed a more dispersive distribution in patients than in controls, indicating a large individual variation in neuronal impairment. We concluded that proton MRS may provide useful information about neuronal impairment in individual patients. J. Magn. Reson Imaging 1999;10:124-129.

Journal of Magnetic Resonance Imaging : JMRI


Light-induced Formation of 2,5-Dihydroxy-p-benzoquinone from Hydroquinone in Photoirradiated Silver-loaded Zirconium Phosphate Suspension

論文題目:銀担持水素リン酸ジルコニウム懸濁液中で光照射下にハイドロキノンから2,5-ジヒドロキシ-p-ベンゾキノンの生成，光照射された銀水素リン酸ジルコニウム懸濁液中で生成したOHラジカルはハイドロキノン存在下で，これを酸化しさらに2個のOHラジカルが付加した2, 5-dihydroxy-p-benzoquinoneを生成することがわかった．その生成機構についてESR測定による生成ラジカルの挙動から明らかにした．

Journal of the Chemical Society. Faraday Transactions


Photochemical property and surface characterization of silver-loaded zirconium phosphate

論文題目:銀担持リン酸ジルコニウムの光化学特性と表面統制解明，銀担持リン酸ジルコニウム懸濁液への光照射により活性酸素ラジカルが生成することがESR測定によりわかった．光電気化学的測定により光カソード電流が観測されたことから，同試料上での光照射による電荷分離が確認された．担持された銀はイオンとして存在し電子プールサイトとして働くことが示唆された．以上より，新規機能性材料が光照射によりOHラジカルを発生することとその試料中での銀イオンの役割を明らかにした．

Journal of Photochemistry and Photobiology A: Chemistry


Role of Cl- adsorbed on silver-loaded zirconium phosphate for the photooxidation of OH- to OH


Proton MR SPectroscopyの定量化における基礎的検討と慢性脳虚血性疾患に対する応用


Proton MRSにおける脳内代謝物の横緩和時間について-定量化に関わる要因として-


Size Determination of Catena-m-(2, 5-dihydroxy-p-benzoquinonatonickel (II) Coordination Polymer Colloid and Its Photochemical Reaction

Journal of Colloid and Interface Science


Radiation induced thermoluminescence of calcium pyrophosphate powders prepared from thulium nitrate aqueous solution


Proton magnetic resonance spectroscopy on childhood-onset dentatorubral-pallidoluysian atrophy(DRPLA)


Therpeutic Efficacy of A Case of Pyruvate Dehydrogenase Complex Deficiency Monitored by Localized Proton Magnetic Resonance Imaging


Coordination of 2,5-dihydroxy-p-benzoquinone to Ni(II) ion


下肢疲労防止に対する弾性ストッキングの着用効果-ヒ腹筋の運動における32-PMRS-


Non-invasive Characterization of Brain Tumor by in-vivo Proton Magnetic Resonance Spectroscopy


先天性筋緊張性ジストロフィー症の脳プロトン磁気共鳴スぺクトロスコピー

先天性筋緊張性ジストロフィー症の脳プロトン磁気共鳴スぺクトロスコピー


99m-Tc標識HMDPおよびMDPのヒドロキシアパタイトへの吸着

99m-Tc標識HMDPおよびMDPのヒドロキシアパタイトへの吸着


Brain Asbcess Observed by Localized Proton Magnetic Resonance Spectroscopy


Accuracy of the results measured by in vivo 1H-MRS using model solution

The Tokushima Journal of Experimental Medicine


TEM observation of iron oxide pillars in montmorillonite


Light-induced Decomposition of Saturated Carboxylic Acids on Iron Oxide-Incorporated Clay Suspended in Aqueous Solutions


Photochemical Properties of PbS Microcrystallites Prepared in Nafion

Journal of the Chemical Society. Faraday Transactions


Photochemical Properties of TiO2 Microcrystallites Prepared in Nafion.,

Bulletin of the Chemical Society of Japan


機能性磁気共鳴画像(FMRI)法を用いた視覚神経系の賦活に関する基礎的検討

機能性磁気共鳴画像(FMRI)法を用いた視覚神経系の賦活に関する基礎的検討

Bulletin of School of Medical Sciences, the University of Tokushima

徳島大学医療技術短期大学部紀要


水溶性高分子で構造化した水に溶解した代謝物質の緩和時間変化

水溶性高分子で構造化した水に溶解した代謝物質の緩和時間変化

徳島大学医療技術短期大学部紀要


固体線量計における相互作用断面積のESRによる検討

固体線量計における相互作用断面積のESRによる検討

徳島大学医療技術短期大学部紀要


1H-MRSによる脳内代謝物質の内部標準としての水の有用性

1H-MRSによる脳内代謝物質の内部標準としての水の有用性

徳島大学医療技術短期大学部紀要


モデル溶液中の脳内代謝物質と水の緩和時間の基礎的検討

モデル溶液中の脳内代謝物質と水の緩和時間の基礎的検討

徳島大学医療技術短期大学部紀要


脳運動野における機能性MRIの基礎的検討

脳運動野における機能性MRIの基礎的検討

徳島大学医療技術短期大学部紀要


1H-MRスペクトロスコピーによる脳内代謝物質の検討

1H-MRスペクトロスコピーによる脳内代謝物質の検討

徳島大学医療技術短期大学部紀要


Evaluation of trap parameter of CaSO4:Tm TLD with TLD reader

Bulletin of School of Medical Sciences, the University of Tokushima


四国及び周辺の温泉水中の環境放射線

四国及び周辺の温泉水中の環境放射線

Natural Science Research, Faculty of Integrated Arts and Sciences, The University of Tokushima

徳島大学総合科学部自然科学研究


ICRP Publication 57 医学系および歯学系作業者の放射線防護

ICRP Publication 57 医学系および歯学系作業者の放射線防護

徳島大学医療技術短期大学部紀要


徳島市における環境放射線

徳島市における環境放射線

徳島大学医療技術短期大学部紀要


Proton MRSにおける脳内代謝物の横緩和時間について-定量化に関わる要因として-