Selective mass enhancement close to the quantum critical point in BaFe2(As1-x P x )2

A quantum critical point (QCP) is currently being conjectured for the BaFe₂(As_1-x P _x )₂ system at the critical value x _c  ≈ 0.3. In the proximity of a QCP, all thermodynamic and transport properties are expected to scale with a single characteristic energy, given by the quantum fluctuations. Such a universal behavior has not, however, been found in the superconducting upper critical field H _c2. Here we report H _c2 data for epitaxial thin films extracted from the electrical resistance measured in very high magnetic fields up to 67 Tesla. Using a multi-band analysis we find that H _c2 is sensitive to the QCP, implying a significant charge carrier effective mass enhancement at the doping-induced QCP that is essentially band-dependent. Our results point to two qualitatively different groups of electrons in BaFe₂(As_1-x P _x )₂. The first one (possibly associated to hot spots or whole Fermi sheets) has a strong mass enhancement at the QCP, and the second one is insensitive to the QCP. The observed duality could also be present in many other quantum critical systems.

Preclinical anticancer effects and toxicologic assessment of hepatic artery infusion of fine-powder cisplatin with lipiodol in vivo

We conducted an in vivo study to evaluate the anticancer effect and toxicity of fine-powder cisplatin suspended in lipiodol (fCDDP/LPD suspension) after a single administration of three different doses to rats via the intrahepatic artery after transplantation of rat ascites hepatoma cells. The toxicity of the fCDDP/LPD suspension was also assessed in the same protocol in noncancer-bearing rats and the observed toxicologic changes were compared among groups administered saline (Sal), an aqueous solution of fCDDP (fCDDP/Sal solution), and LPD alone. In parallel with the toxicity test, plasma CDDP concentrations were compared between the fCDDP/LPD suspension and fCDDP/Sal solution. The mean weight of the tumors in the fCDDP/LPD suspension groups was significantly less than in the LPD-alone group. The pathologic changes in the liver observed in the fCDDP/LPD suspension group increased with dose, were more marked compared with those in the fCDDP/Sal solution and LPD-alone groups, and were reversible. No other toxicologic effects were observed. The concentration of CDDP in the plasma in the fCDDP/LPD suspension group was slightly lower than that in the fCDDP/Sal solution group. In conclusion, the results indicate that the fCDDP/LPD suspension has sufficient anticancer efficacy and tolerability for use in the clinical treatment of hepatocellular carcinoma.

Search for charged Higgs bosons in e+e- collisions at [Formula: see text]

A search is made for charged Higgs bosons predicted by Two-Higgs-Doublet extensions of the Standard Model (2HDM) using electron-positron collision data collected by the OPAL experiment at [Formula: see text], corresponding to an integrated luminosity of approximately 600 pb-1. Charged Higgs bosons are assumed to be pair-produced and to decay into [Formula: see text], τντ or AW±. No signal is observed. Model-independent limits on the charged Higgs-boson production cross section are derived by combining these results with previous searches at lower energies. Under the assumption [Formula: see text], motivated by general 2HDM type II models, excluded areas on the [Formula: see text] plane are presented and charged Higgs bosons are excluded up to a mass of 76.3 GeV at 95 % confidence level, independent of the branching ratio BR(H±→τντ ). A scan of the 2HDM type I model parameter space is performed and limits on the Higgs-boson masses [Formula: see text] and mA are presented for different choices of tanβ.

Identification of the plague reservoir in an endemic area of Zambia

Yersinia pestis, the bacterial agent of plague, is primarily a parasite of wild rodents that persists in permanent, discrete enzootic foci throughout the world. The disease is transmitted in humans by bites from fleas of wildlife rodent species. Therefore surveillance is the ultimate public health solution through plague detection in domestic dogs, other carnivores and wild rodents. The investigations of die-offs amongst plague-susceptible colonial rodents are also significant to determine the presence of Y. pestis in a susceptible population.This study details the identification of the plague reservoir in a suspected endemic area of Zambia. The study was undertaken through rodent investigation for the presence of Y. pestis. A total of 105 rodents were sampled routinely and during a suspected plague period. On dissection 4 (3.81%, 95% CI: 1.23−10.0) rodents sampled during an outbreak showed signs of spleen enlargement. The blood, liver, lymph nodes and spleen of each rodent were subjected to culture on 6% sheep blood agar and MaCconkey agar. Colonies obtained were identified as Y. pestis by colony morphologic features, biochemical profiles, mouse inoculation assay and polymerase chain reaction (PCR). The PCR primers used targeted the Y. pestis plasminogen activator gene, chromosomal ferric iron uptake regulation gene and the outer membrane protein B gene.The isolates were also subjected to antibiotic sensitivity tests using the disk diffusion method on Mueller-Hinton agar with sensitivity being observed with ampicillin, amoxicillin, chloramphenicol, gentamycin, streptomycin, tetracycline and trimethoprim-sulfamethoxazole. The findings, identifies a natural reservoir of Y. pestis in Zambia providing the public health officials with a definite host for the control strategy.

First observation of B(s)(0) → J/ψη and B(s)(0) → J/ψη'

We report first observations of B(s)(0) → J/ψη and B(s)(0) → J/ψη'. The results are obtained from 121.4  fb(-1) of data collected at the Υ(5S) resonance with the Belle detector at the KEKB e+ e- collider. We obtain the branching fractions B(B(s)(0) → J/ψη)=[5.10±0.50(stat)±0.25(syst)(-0.79)(+1.14)(N(B(s)(*) B(s)(*))]×10(-4), and B(B(s)(0) → J/ψη')=[3.71±0.61(stat)±0.18(syst)(-0.57)(+0.83)(N(B(s)(*) B(s)(*))]×10(-4). The ratio of the two branching fractions is measured to be (B(B(s) → J/ψη'))/(B(B(s) → J/ψη))=0.73±0.14(stat)±0.02(syst).

Effect of PSK on FOLFOX4-induced peripheral neuropathy and bone marrow suppression in patients with metastatic colorectal cancer

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Background: FOLFOX4 has been confirmed as an effective treatment for metastatic colorectal cancer and is used as a postoperative adjuvant therapy. However adverse effects such as cold-sensitive paresthesia and bone marrow suppression are common and may necessitate changes in chemotherapy regimen despite FOLFOX effectiveness. PSK, a polysaccharide derived from a species of mushroom, has been developed in Japan as an immune-enhancing agent and is widely used in patients with gastric, colorectal and pulmonary cancer. PSK has also been reported to decrease some adverse effects of chemotherapy.

Methods: FOLFOX4 combined with PSK was administered to patients with metastatic colorectal cancer and the results were evaluated. Eight cycles of FOLFOX4 and PSK (3.0 g/day, p.o.) were given to 25 patients with metastatic colorectal cancer (19 hepatic, 3 pulmonary and 3 peritoneal).

Results: No patients showed CR (complete response, 0%) while PR (partial response), SD (stable disease) and PD (progressive disease) were seen in 48%, 36% and 16% of patients, respectively. Response rate was 48% and disease control rate was 84%. Frequency of adverse effects was significantly lower than described in the published data. Grades 1 and 3 neutropenia occurred in 48% and 24% of patients, respectively; grades 1 and 3 nausea in 48% and 4%, respectively; and grades 1, 2 and 3 sensory neurotoxicity in 52%, 4% and 0%, respectively. No patient dropped out due to adverse effects in this study.

Conclusions: PSK plus FOLFOX4 seems as effective as FOLFOX4 monotherapy, and significantly less toxic. These results suggest that this combination therapy may be more effective when given for a longer period, with lower incidence of adverse effects.

No significant financial relationships to disclose.

Distinct propagation efficiencies of H5N1 influenza virus Thai isolates in newly established murine respiratory region-derived cell clones

Inbred mice have been widely used for the study of influenza viruses as a mammalian model, while suitable cell lines derived from murine tissue have been limited. Here, we established several immortalized cell clones from respiratory regions of inbred mice (C57BL/6 and BALB/c) by transformation using simian virus 40 large T antigen expression vector. Twenty-five cell clones from C57/BL and BALB/c, designated as MRDC/C and MRDC/B series, respectively, showed different susceptibility to Thai isolates of influenza A virus H5N1. Two murine cell clones, C6 and B7 which were extensively studied expressed both SAα2,3 and SAα2,6 sialic acid receptors. Interestingly, the 6 Thai patient-derived H5N1 isolates examined showed varied virus propagation efficiency in murine cell clones, although there were only slight differences in their propagation in MDCK and A549 cell lines. The results indicate that the murine cell clones are useful for examining the propagation efficiency of H5N1 viruses in vitro.

Preparation of polyelectrolyte-coated pH-sensitive poly(styrene) microcapsules and their application to initiation-cessation control of an enzyme reaction

Poly(styrene) microcapsules, prepared by depositing the polymer around emulsified aqueous droplets, were coated with a synthesized polyelectrolyte; i.e., copolymer of maleic acid (MA) with methyl vinyl ether (MVE), co-poly(MA, MVE), or with styrene (St), copoly(Ma, St). The permeability of the capsule membrane was investigated under various pHs of the outer medium using n-propyl alcohol as a permeant. It became apparent that either copoly(MA, St)- or copoly(MA, MVE)-coated microcapsules function as a pH-sensitive capsule. In particular, the former showed a dramatic change of the permeability in response to small differences in pH (5-6). By reference to the viscometric and electrophoretic studies of both copolymers, these were interpreted as being due to a pH-induced alteration of the configuration of the copolymer coating on the surface of the capsule membrane. When sucrose was hydrolyzed in an aqueous suspension of the copoly(MA, St)-coated capsules into which invertase was loaded, the hydrolytic reaction was initiated at pH 5. 5 and stopped at pH 4. 5. Such initiation-cessation control was repeated reversibly without damaging the capsules.

Febrile period and maximum body temperature in patients with measles over 15 years old

The medical records of Japanese patients with measles, age 15 to 39 years old, were analyzed for febrile period in 200 patients and maximum body temperature in 211 patients. The febrile periods by age group were as follows: 7.7 +/- 1.4 days, 7.8 +/- 1.7 days, 8.1 +/- 1.7 days, 8.1 +/- 2.4 days and 7.5 +/- 1.4 days in 15-19, 20-24, 25-29, 30-34 and 35-39 year-olds, respectively. No significant differences in febrile periods were identified among the different age groups. A maximum body temperature over 40 degrees C was seen in 61, 58, 59, 50 and 33% of the 15-19, 20-24, 25-29, 30-34 and 35-39 year-olds, respectively. The results of our study indicate age is not a determining factor for febrile period, but maximum body temperature may be lower in older than in younger patients with measles.

Measurement of branching fractions, isospin, and CP-violating asymmetries for exclusive b-->dgamma modes

We report new measurements of the decays B+-->rho+gamma, B0-->rho0gamma, and B0-->omegagamma using a data sample of 657x10(6) B meson pairs accumulated with the Belle detector at the KEKB e+e- collider. We measure branching fractions B(B+-->rho+gamma)=(8.7_-2.7-1.1;+2.9+0.9)x10(-7), B(B0-->rho0gamma)=(7.8_-1.6-1.0;+1.7+0.9)x10(-7), and B(B0-->omegagamma)=(4.0_-1.7;+1.9+/-1.3)x10(-7). We also report the isospin asymmetry Delta(rhogamma)=-0.48_-0.19-0.09;+0.21+0.08 and the first measurement of the direct CP-violating asymmetry ACP(B+-->rho+gamma)=-0.11+/-0.32+/-0.09, where the first and second errors are statistical and systematic, respectively.

GPI-anchorless human prion protein is secreted and glycosylated but lacks superoxide dismutase activity

Prion protein (PrP) is a glycosylphosphatidylinositol (GPI)-anchored membrane protein that is thought to play a role in anti-oxidative stress. It remains controversial whether PrP elicits superoxide dismutase (SOD) activity itself or indirectly by activating cellular SOD. Our previous studies showed that soluble PrP produced by a baculovirus expression system did not exhibit any SOD activity in a marginally glycosylated form. In the present study, we developed a mammalian expression system for a truncated soluble form of human prion protein with the native signal peptide but without a GPI-anchor site, driven by the peptide chain elongation factor 1alpha promoter in stably transfected rabbit-kidney epithelial RK13 cells, to investigate the SOD activity of mammalian PrP. This recombinant product, denoted sPrP, is secreted in large quantities in medium and can be isolated in very high purity and yield (more than 1 mg sPrP per 2 litres medium). Characterization by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and tunicamycin treatment revealed that a fully glycosylated form of sPrP was secreted from the cells. SOD activity in cell lysate showed a decrease in sPrP-expressing RK13 cells and an increase in wild-type PrP-expressing RK13 cells compared to empty vector-transfected RK13 cells or parent cells. Purified or immunoprecipitated sPrP did not show any SOD activity. In conclusion, the GPI-anchor site, but not glycosylation, appears to be essential for the secretion of PrP. In addition, mammalian PrP itself does not act as a functional SOD enzyme.

Search for B --> h(*)nunu[over ] decays at Belle

We present a search for the rare decays B --> h(*)nunu[over ], where h(*) stands for a light meson. A data sample of 535 x 10{6} BB[over ] pairs collected with the Belle detector at the KEKB e{+}e{-} collider is used. Signal candidates are required to have an accompanying B meson fully reconstructed in a hadronic mode and signal side particles consistent with a single h(*) meson. No significant signal is observed and we set upper limits on the branching fractions at 90% confidence level. The limits on B{0} --> K{*0}nunu[over ] and B{+} --> K{+}nunu[over ] decays are more stringent than the previous constraints, while the first searches for B{0} --> K{0}nunu[over ], pi{0}nunu[over ], rho{0}nunu[over ], varphinunu[over ] and B{+} --> K{*+}nunu[over ], rho{+}nunu[over ] are reported.

Observation of B(0)-->D(*-)tau(+)nu(tau) decay at Belle

We report an observation of the decay B{0}-->D{*-}tau{+}nu{tau} in a data sample containing 535x10{6} BB pairs collected with the Belle detector at the KEKB asymmetric-energy e{+}e{-} collider. We find a signal with a significance of 5.2sigma and measure the branching fraction B(B{0}-->D{*-}tau{+}nu{tau})=(2.02{-0.37}{+0.40}(stat)+/-0.37(syst))%. This is the first observation of an exclusive B decay with a b-->ctaunu{tau} transition.

Measurement of D0-D0 mixing parameters in D0 --> Ks pi+ pi- decays

We report a measurement of D0-D(0) mixing parameters in D(0) --> K(s)(0) pi(+) pi(-) decays using a time-dependent Dalitz-plot analysis. We first assume CP conservation and subsequently allow for CP violation. The results are based on 540 fb(-1) of data accumulated with the Belle detector at the KEKB e(+)e(-) collider. Assuming negligible CP violation, we measure the mixing parameters x = (0.80 +/- 0.29(-0.07-0.14)(+0.09+0.10))% and y = (0.33+/-0.24(-0.12-0.08)(+0.08+0.06))%, where the errors are statistical, experimental systematic, and systematic due to the Dalitz decay model, respectively. Allowing for CP violation, we obtain the CP-violating parameters |q / p| = 0.86(-0.29-0.03)(+0.30+0.06) +/- 0.08 and arg(q/p) = (-14(-18-3-4)(+16+5+2)) degrees .