Charge Transport in Ba1−x_{1-x}Rbx_{x}Fe2_{2}As2_{2} Single Crystals

Recent studies in heavily hole-doped iron-based superconductor RbFe$_2$As$_2$ have suggested the emergence of novel electronic nematicity directed along the Fe-As direction, 45$^\circ$ rotated from the usual nematicity ubiquitously found in BaFe$_2$As$_2$ and related materials. This motivates us to study the physical properties of Ba$_{1-x}$Rb$_{x}$Fe$_{2}$As$_{2}$, details of which remain largely unexplored. Here we report on the normal-state charge transport in Ba$_{1-x}$Rb$_{x}$Fe$_{2}$As$_{2}$ superconductors by using high-quality single crystals in the range of Rb concentration $0.14\le x \le 1.00$. From the systematic measurements of the temperature dependence of electrical resistivity $\rho(T)$, we find a signature of a deviation from the Fermi liquid behavior around the optimal composition, which does not seem related to the antiferromagnetic quantum criticality but has a potential link to hidden nematic quantum criticality. In addition, electron correlations derived from the coefficient of $T^2$ resistivity show a marked increase with Rb content near the heavily hole-doped end, consistent with the putative Mott physics near the $3d^5$ electron configuration in iron-based superconductors.Comment: 6 pages, 4 figure

In vitro characterization of cells derived from chordoma cell line U-CH1 following treatment with X-rays, heavy ions and chemotherapeutic drugs

<p>Abstract</p> <p>Background</p> <p>Chordoma, a rare cancer, is usually treated with surgery and/or radiation. However, very limited characterizations of chordoma cells are available due to a minimal availability (only two lines validated by now) and the extremely long doubling time. In order to overcome this situation, we successfully derived a cell line with a shorter doubling time from the first validated chordoma line U-CH1 and obtained invaluable cell biological data.</p> <p>Method</p> <p>After isolating a subpopulation of U-CH1 cells with a short doubling time (U-CH1-N), cell growth, cell cycle distribution, DNA content, chromosome number, p53 status, and cell survival were examined after exposure to X-rays, heavy ions, camptothecin, mitomycin C, cisplatin and bleocin. These data were compared with those of HeLa (cervical cancer) and U87-MG (glioblastoma) cells.</p> <p>Results</p> <p>The cell doubling times for HeLa, U87-MG and U-CH1-N were approximately 18 h, 24 h and 3 days respectively. Heavy ion irradiation resulted in more efficient cell killing than x-rays in all three cell lines. Relative biological effectiveness (RBE) at 10% survival for U-CH1-N was about 2.45 for 70 keV/μm carbon and 3.86 for 200 keV/μm iron ions. Of the four chemicals, bleocin showed the most marked cytotoxic effect on U-CH1-N.</p> <p>Conclusion</p> <p>Our data provide the first comprehensive cellular characterization using cells of chordoma origin and furnish the biological basis for successful clinical results of chordoma treatment by heavy ions.</p

EFFICACY OF INTERFERON THERAPY FOR CHRONIC HEPATITIS C ： A COOPERATIVE STUDY IN ELEVEN HOSPITALS

We investigated the influences of liver histology，serum levels of hepatitis C virus (HCV) and HCV genotypes on responsiveness to interferon (IFN) therapy in 342 patients with chronic hepatitis C. Either 9 million units (MU) of lymphoblastoid alpha IFN or 3 MU of recombinant IFN-alpha was administered daily for 2 weeks and then three times a week for 22 weeks. IFN responses were divided into three groups on the basis of the results of polymerase chain reaction (PCR) assay detecting HCV-RNA in serum. Complete response (CR) was defined as sustained elimination of HCV for at least 6 months after treatment，partial response (PR) as HCV elimination for a limited period，non-response (NR) as continuously positive for HCV-RNA in serum. Quantitation of pre-treament HCV-RNA amount in serum was determined by competitive PCR assay in 47 patients. HCV genotyping was performed in 114 patients by PCR with genotype-specific primers. CR was obtained in 97 patients (28.4%)，PR in 104 (30.4%) and NR in 141 (41.2%). IFN responses，represented by CR/PR/NR，were 15/18/11 in 44 patients with chronic persistent hepatitis (CPH)，72/65/73 in 210 patients with chronic aggressive hepatitis (CAH) 2a，and 10/21/57 in 88 patients with CAH2b. CR rate was lower in patients with CAH2b (11.4%) compared to those with CPH (34.1%) or CAH2a (34.3%). Averages of pre-treatment serum HCV-RNA amount (copies/50μl) were 10³·⁵⁵ in 13 CRs，10⁴·⁵⁶ in 17 PRs，and 10⁵·⁹⁵ in 17 NRs. There was a positive correlation between pre-treatment HCV-RNA levels and IFN unresponsiveness. HCV genotyping in 114 patients revealed that HCV type Ⅰ infection was observed in one，type Ⅱ in 94，type Ⅲ in 11，type Ⅳ in 6 and mixed (types Ⅱ and Ⅳ) in 2 patients，and their IFN responses (CR/PR/NR) were 0/0/1，28/26/40，3/5/3，1/3/2 and 0/1/1，respectively

A simulation environment to simulate lower-hybrid-wave-driven plasmas efficiently

In this study a hybrid simulation environment to investigate the lower-hybrid-wave-driven tokamak plasmas is presented, and its application to the spherical tokamak TST-2 is described. These plasma are formed and driven by radio-frequency waves without the use of the central solenoid, and are characterized by low density and low magnetic field. A hybrid simulation environment which is divided into two groups, one using magneto-hydrodynamic (MHD) as well as particle-in-cell (PIC) approaches, and the second group using ray-tracing and Fokker–Planck solvers, is applied to describe the behavior of energetic electrons, bulk plasma, wave propagation, and the wave-particle interaction. Both groups of solvers can be coupled via the energetic-particle velocity distribution function and the equilibrium conditions of magnetic field, pressure, and density profiles to obtain a self-consistent solution. First results show the impact of a self-consistent equilibrium on ray trajectories and current density profiles. Therefore, new insights in lower-hybrid-wave-driven plasmas of TST-2 can be obtained using the proposed hybrid simulation environment

THYROID DYSFUNCTION FOLLOWING ALPHA-INTERFERON TREATMENT FOR CHRONIC HEPATITIS C

In order to evaluate the influnces of IFNα on thyroid function, thyroid-stimulating hormone (TSH), total thyroxine (T4), free T4, tri-iodothyronine (T3), and thyroxine-binding globulin were examined in IFNα-treated 351 patients with chronic hepatitis C before and during therapy. As therapy, either 3 million units (MU) of human lymphoblastoid IFNα or 9MU of recombinant IFNα2a was administrated daily for the initial two weeks followed by three times a week for 22 weeks. There were nine patients showing thyroid dysfunction during IFNα therapy. They consist of one relapse of Graves' disease, one relapse of Hashimoto thyroiditis, one development of apparent thyroid insufficiency from subclinical hypothyroidism, five cases with transient hyperthyroidism and one case with transient hypothyroidism. T4 and T3 levels in most patients who transiently developed thyroid dysfunction were normalized spontaneously after the discontinuation of IFNα. Thyroid-related autoantibodies were positive in 4 patients before IFNα therapy and newly developed in one patient during therapy. Attention should be paid first to the previous histories of autoimmune thyroid diseases and the existence of thyroid-related autoantibodies for the prediction of development of thyroid dysfunction during IFNα therapy. In addition, serial examinations of TSH, T3 and T4 should be also necessary for early detection of transient thyroid dysfunction during IFNα therapy

Microsomal prostaglandin E synthase-1 in both cancer cells and hosts contributes to tumour growth, invasion and metastasis

mPGES-1 (microsomal prostaglandin E synthase-1) is a stimulus-inducible enzyme that functions downstream of COX (cyclo-oxygenase)-2 in the PGE2 (prostaglandin E2)-biosynthesis pathway. Although COX-2-derived PGE2 is known to play a role in the development of various tumours, the involvement of mPGES-1 in carcinogenesis has not yet been fully understood. In the present study, we used LLC (Lewis lung carcinoma) cells with mPGES-1 knockdown or overexpression, as well as mPGES-1-deficient mice to examine the roles of cancer cell- and host-associated mPGES-1 in the processes of tumorigenesis in vitro and in vivo. We found that siRNA (small interfering RNA) silencing of mPGES-1 in LLC cells decreased PGE2 synthesis markedly, accompanied by reduced cell proliferation, attenuated Matrigel™ invasiveness and increased extracellular matrix adhesion. Conversely, mPGES-1-overexpressing LLC cells showed increased proliferating and invasive capacities. When implanted subcutaneously into wild-type mice, mPGES-1-silenced cells formed smaller xenograft tumours than did control cells. Furthermore, LLC tumours grafted subcutaneously into mPGES-1-knockout mice grew more slowly than did those grafted into littermate wild-type mice, with concomitant decreases in the density of microvascular networks, the expression of pro-angiogenic vascular endothelial growth factor, and the activity of matrix metalloproteinase-2. Lung metastasis of intravenously injected LLC cells was also significantly less obvious in mPGES-1-null mice than in wild-type mice. Thus our present approaches provide unequivocal evidence for critical roles of the mPGES-1-dependent PGE2 biosynthetic pathway in both cancer cells and host microenvironments in tumour growth and metastasis

Narrow-band imaging with magnifying endoscopy for Peyer's patches is useful in predicting the recurrence of remissive patients with ulcerative colitis

Background/AimsPeyer's patches (PPs) are aggregates of lymphoid follicles that are mainly located in the distal ileum; they play a major role in mucosal immunity. We recently reported that patients with ulcerative colitis (UC) have alterations in PPs that can be detected using narrow-band imaging with magnifying endoscopy (NBI-ME). However, the usefulness of NBI-ME in UC treatment as a whole is still unknown.MethodsWe collected NBI-ME images of PPs from 67 UC patients who had undergone ileocolonoscopy. We evaluated changes in the villi using the "villi index," which is based on three categories: irregular formation, hyperemia, and altered vascular network pattern. The patients were divided into two groups on the basis of villi index: low (L)- and high (H)-types. We then determined the correlation between morphological alteration of the PPs and various clinical characteristics. In 52 patients who were in clinical remission, we also analyzed the correlation between NBI-ME findings of PPs and clinical recurrence.ResultsThe time to clinical recurrence was significantly shorter in remissive UC patients with H-type PPs than in those with L-type PPs (P<0.01). Moreover, PP alterations were not correlated with age, sex, disease duration, clinical activity, endoscopic score, or extent of disease involvement. Multivariate analysis revealed that the existence of H-type PPs was an independent risk factor for clinical recurrence (hazard ratio, 3.3; P<0.01).ConclusionsUC patients with morphological alterations in PPs were at high risk of clinical relapse. Therefore, to predict the clinical course of UC, it may be useful to evaluate NBI-ME images of PPs

High-resolution photoelectron spectroscopy study of Kondo metals : SmSn3 and Sm0.9La0.1Sn3

We performed a high-resolution photoelectron spectroscopy study on the Kondo metals SmSn3 and Sm0.9La0.1Sn3. The experimental results are compared with calculations of density of state performed within the local density approximation plus the dynamical mean-field theory. The theory is found to reproduce the experimental valence-band spectra well. In both SmSn3 and Sm0.9La0.1Sn3 the bulk Sm valence is nearly trivalent, with a small fraction of divalent component. Resonant photoelectron spectroscopy indicates a decrease in the Kondo effect in the diluted system Sm0.9La0.1Sn3