Pseudogap Phase Boundary in Overdoped Bi_2Sr_2CaCu_2O_8 Studied by Measuring Out-of-plane Resistivity under the Magnetic Fields

The characteristic pseudogap temperature T* in Bi2Sr2CaCu2O8 system has been systematically evaluated as a function of doping, especially focusing on its overdoped region, by measuring the out-of-plane resistivity under the magnetic fields. Overdoped samples have been prepared by annealing TSFZ-grown Bi2Sr2CaCu2O8 single crystals under the high oxygen pressures (990 kgf/cm2). At a zero field, the out-of-plane resistivity showed a metallic behavior down to Tc (= 62 K), while under the magnetic fields of over 3 T,it showed typical upturn behavior from around 65 K upon decreasing temperature. This result suggests that the pseudogap and superconductivity are different phenomena.Comment: 2 pages, 2 figures. Final version accepted for the Proceedings of the M2S-IX Conference (Tokyo, September 2009

In vivo manipulation of fluorescently labeled organelles in living cells by multiphoton excitation

Wataru Watanabe, Sachhiro Matsunaga, Tsunehito Higashi, Kiichi Fukui, and Kazuyoshi Itoh "In vivo manipulation of fluorescently labeled organelles in living cells by multiphoton excitation," Journal of Biomedical Optics 13(3), 031213 (1 May 2008). https://doi.org/10.1117/1.293940

Femtosecond laser manipulation of subcellular organelles in living cells

European Conferences on Biomedical Optics 2005, 2005, Munich, GermanyWataru Watanabe, Tomoko Shimada, Kazuyoshi Itoh, Sachihiro Matsunaga, Kiichi Fukui, "Femtosecond laser manipulation of subcellular organelles in living cells," Proc. SPIE 5863, Therapeutic Laser Applications and Laser-Tissue Interactions II, 58630B (26 August 2005); https://doi.org/10.1117/12.633079

Spin-orbit coupling inactivity of Co2+^{2+} ion in geometrically frustrated magnet GeCo2_2O4_4

We report single-crystal neutron diffraction studies on a spinel antiferromagnet GeCo$_2$O$_4$, which exhibits magnetic order with a trigonal propagation vector and tetragonal lattice expansion ($c/a\simeq1.001$) below $T_{\rm N}=21$ K. For this inconsistency between spin and lattice in symmetry, magnetic Bragg reflections with a tetragonal propagation vector were discovered below $T_{\rm N}$. We discuss spin and orbital states of Co$^{2+}$ ion underlying the new magnetic component.Comment: 3 pages 2 figures, submitted to ICFCM proceeding (Journal of Physics: Conference Series, 2011

Nanosurgery of sub-cellular organelles in living cells using a femtosecond laser oscillator

Lasers and Applications in Science and Engineering, 2006, San Jose, California, United StatesWataru Watanabe, Tomoko Shimada, Sachihiro Matsunaga, Hiroshi Ishii, Tsunehito Higashi, Kiichi Fukui, Kazuyoshi Itoh, "Nanosurgery of sub-cellular organelles in living cells using a femtosecond laser oscillator," Proc. SPIE 6108, Commercial and Biomedical Applications of Ultrafast Lasers VI, 610804 (28 February 2006); https://doi.org/10.1117/12.645474

3D quantitative analysis of diffusion-weighted imaging for predicting the malignant potential of intraductal papillary mucinous neoplasms of the pancreas

Purpose: To investigate the predictors of intraductal papillary mucinous neoplasms of the pancreas (IPMNs) with high-grade dysplasia, using 2-dimensional (2D) analysis and 3-dimensional (3D) volume-of-interest-based apparent diffusion coefficient (ADC) histogram analysis. Material and methods: The data of 45 patients with histopathologically confirmed IPMNs with high-grade or lowgrade dysplasia were retrospectively assessed. The 2D analysis included lesion-to-spinal cord signal intensity ratio (LSR), minimum ADC value ($ADC_{min}$), and mean ADC value ($ADC_{mean}$). The 3D analysis included the overall mean ($ADC_{overall mean}$), mean of the bottom 10th percentile ($ADC_{mean0-10}$), mean of the bottom 10-25th percentile ($ADC_{mean10-25}$), mean of the bottom 25-50th percentile ($ADC_{mean25-50}$), skewness ($ADC_{skewness}$), kurtosis ($ADC_{kurtosis}$), and entropy ($ADC_{entropy}$). Diagnostic performance was compared by analysing the area under the receiver operating characteristic curve (AUC). Inter-rater reliability was assessed by blinded evaluation using the intraclass correlation coefficient. Results: There were 16 and 29 IPMNs with high- and low-grade dysplasia, respectively. The LSR, $ADC_{overall mean}$, $ADC_{mean0-10}$, $ADC_{mean10-25}$, $ADC_{mean25-50}$, and $ADC_{entropy}$ showed significant between-group differences (AUC = 72-93%; p < 0.05). Inter-rater reliability assessment showed almost perfect agreement for LSR and substantial agreement for $ADC_{overall mean}$ and $ADC_{entropy}$. Multivariate logistic regression showed that $ADC_{overall mean}$ and $ADC_{entropy}$ were significant independent predictors of malignancy (p < 0.05), with diagnostic accuracies of 80% and 73%, respectively. Conclusion: $ADC_{overall mean}$ and $ADC_{entropy}$ from 3D analysis may assist in predicting IPMNs with high-grade dysplasia

Antibacterial Effects of Disulfiram in Helicobacter pylori

Background: Helicobacter pylori infection poses a risk of the occurrence of gastrointestinal diseases, such as gastric cancer. Its incidence rate is significantly reduced by eradication, and thereby, eradication therapy is generally performed. Disulfiram is an oral prescription drug mainly used for the treatment of alcohol dependence. In recent years, reports have been made on its anticancer and antibacterial effects, and thus, it has recently become an interesting subject. This study aimed to examine the antibacterial activity of disulfiram, investigate the presence or absence of its antibacterial activity on H. pylori, and determine whether it could be a new bactericidal drug against drug-resistant H. pylori. Materials and Methods: Drug-sensitive strains of H. pylori and amoxicillin-resistant, clarithromycin-resistant, and metronidazole-resistant strains were used, and a growth inhibition test of H. pylori using disulfiram was performed. Furthermore, the expression of urease, vacuolating cytotoxin A (VacA), and CagA, the virulence proteins of H. pylori, was quantitatively analyzed using the Western blotting method. In addition, for H. pylori used in this study, the 16SrDNA sequence, a ribosomal gene involved in protein production, was analyzed to examine the presence or absence of gene mutation. Results: Disulfiram suppressed the growth of 7 out of 12 H. pylori strains at 1 mu g/mL, and no correlation was observed between their susceptibility/resistance to current eradication antimicrobial drugs and disulfiram resistance. Disulfiram reduced the expression levels of urease, VacA, and CagA proteins. H. pylori, which showed resistance to disulfiram, tended to have fewer gene deletions/insertions in the 16S rDNA sequence; however, no specific mutation was detected. Conclusion: Disulfiram has a bactericidal effect on H. pylori at low concentrations, suggesting that it can be used as a supplement for current H. pylori eradication drugs

Serodiagnosis and Bacterial Genome of Helicobacter pylori Infection

The infection caused by Helicobacter pylori is associated with several diseases, including gastric cancer. Several methods for the diagnosis of H. pylori infection exist, including endoscopy, the urea breath test, and the fecal antigen test, which is the serum antibody titer test that is often used since it is a simple and highly sensitive test. In this context, this study aims to find the association between different antibody reactivities and the organization of bacterial genomes. Next-generation sequences were performed to determine the genome sequences of four strains of antigens with different reactivity. The search was performed on the common genes, with the homology analysis conducted using a genome ring and dot plot analysis. The two antigens of the highly reactive strains showed a high gene homology, and Western blots for CagA and VacA also showed high expression levels of proteins. In the poorly responsive antigen strains, it was found that the inversion occurred around the vacA gene in the genome. The structure of bacterial genomes might contribute to the poor reactivity exhibited by the antibodies of patients. In the future, an accurate serodiagnosis could be performed by using a strain with few gene mutations of the antigen used for the antibody titer test of H. pylori