Half-integer quantized anomalous thermal Hall effect in the Kitaev material candidate α-RuCl3.

Half-integer thermal quantum Hall conductance has recently been reported for the two-dimensional honeycomb material α-RuCl3 We found that the half-integer thermal Hall plateau appears even for a magnetic field with no out-of-plane components. The measured field-angular variation of the quantized thermal Hall conductance has the same sign structure as the topological Chern number of the pure Kitaev spin liquid. This observation suggests that the non-Abelian topological order associated with fractionalization of the local magnetic moments persists even in the presence of non-Kitaev interactions in α-RuCl3.

An origin of excess vibrational entropies at grain boundaries in Al, Si and MgO: a first-principles analysis with lattice dynamics.

First-principles lattice dynamics is applied to symmetric tilt grain boundaries (GBs) in Al, Si and MgO, with the goal of revealing critical factors in determining excess vibrational entropies at the atomic level. Excess vibrational entropies at GBs are found to vary depending on the substances. Al GBs tend to show larger excess entropies and hence larger temperature dependence of the GB free energies than those in Si and MgO. Most of the Si GBs show small excess entropies. For Al and MgO, atom-projected vibrational entropies are well correlated with bond-length changes at GB cores, and have large positive values as bond lengths increase for GB atoms. This demonstrates that a similar mechanism likely dominates excess vibrational entropies of GBs for both substances, despite their dissimilar bonding nature. For Si GBs, atoms with threefold coordination do not simply follow such a correlation, implying the importance of other factors that are different from bond-length changes. These systematic comparisons will be a foothold for understanding a physical origin of excess entropies at GBs even in more complex substances.

First-principles based theoretical calculations of atomic structures of hydroxyapatite surfaces and their charge states in contact with aqueous solutions.

Surface charge states of biomaterials are often important for the adsorption of cells, proteins, and foreign ions on their surfaces, which should be clarified at the atomic and electronic levels. First-principles calculations were performed to reveal thermodynamically stable surface atomic structures and their charge states in hydroxyapatite (HAp). Effects of aqueous environments on the surface stability were considered using an implicit solvation model. It was found that in an air atmosphere, stoichiometric {0001} and P-rich {101̄0} surfaces are energetically favorable, whereas in an aqueous solution, a Ca-rich {101̄0} surface is the most stable. This difference suggests that preferential surface structures strongly depend on chemical environments with and without aqueous solutions. Their surface potentials at zero charge were calculated to obtain the isoelectric points (pHPZC). pHPZC values for the {0001} surface and the Ca-rich {101̄0} surface were obtained to be 4.8 and 8.7, respectively. This indicates that in an aqueous solution at neutral pH, the {0001} and Ca-rich {101̄0} surfaces are negatively and positively charged, respectively. This trend agrees with experimental data from chromatography and zeta potential measurements. Our methodology based on first-principles calculations enables determining macroscopic charge states of HAp surfaces from atomic and electronic levels.

Retrospective analysis of the survival benefit of chemotherapy for recurrent or advanced epithelial ovarian carcinoma in patients previously treated with paclitaxel plus platinum-based chemotherapy.

AIM: The outcomes of treatment for women with recurrent or advanced epithelial ovarian carcinoma previously treated with pacli- taxel plus platinum-based chemotherapy were analyzed. MATERIALS AND METHODS: Retrospective analysis was performed in a total of 65 series of treatments provided for 35 patients with a history of paclitaxel plus platinum-based chemotherapy. The chemotherapy regimens used were classified into the following four types for analysis: conventional paclitaxel plus carboplatin therapy (TC arm), pegylated liposomal doxorubicin-containing regimens (PLD arm), CPT-11-containing regimens (CPT-11 arm), and others. Disease-control rates (DCRs) were compared and subjected to univariate analysis. Progression-free survival (PFS) was determined from the date of the first cycle of each chemotherapy with the Kaplan-Meier method, and comparisons were performed using the log-rank test. RESULTS: DCR was 80%, 71%, and 26% for the TC, PLD, and CPT-l arms, respectively. The median PFS was 286, 372, and 76 days for the TC, PLD, and CPT-11 arms, respectively. There was no discernible difference in PFS between the TC and the PLD arm. In contrast, PFS of the CPT- 11 arm was significantly shorter than that of the TC and PLD arms. In addition, three of seven (42.9%) treatments in the PLD arm maintained a progression-free period for longer than one year, while only one of 25 (4%) treatments in the TC arm maintained a progression-free period for more than one year. CONCLUSIONS: The PFS of PLD is similar to that of TC. PLD-containing regimens might have a potential benefit with a higher PFS over one year than the TC regimen.

Hyponatremia and hypokalemia as risk factors for falls.

BACKGROUND/OBJECTIVES: Fall accidents may reduce an individual's quality of life and ability to perform the activities of daily life, and may delay recovery from illness. Consequently, medical institutions need to take measures to prevent falls. There are various risk factors for falls, including advanced age, illness and medication effects. Although hyponatremia and hypokalemia have been reported to increase the rate of falls, how they affect falls is not fully understood. SUBJECTS/METHODS: We retrospectively examined 2948 patients, ⩾18 years old who had been hospitalized for ⩾3 days at Gifu (Japan) Municipal Hospital between May 2012 and April 2013 to determine the effects of hyponatremia and hypokalemia on the risk of falls. After the patients had been divided into fall and non-fall groups, their data were subjected to univariate and multiple regression analysis to identify significant differences. RESULTS: The univariate analysis results revealed significant differences between the groups in terms of age (⩾65 years); the presence of hyponatremia, hypokalemia, central nervous system disease, cardiovascular disease and/or peripheral nerve/muscular disease; intake of medications that increase the risk of falls; and increased sedative dosage. The multivariate analysis results revealed significant differences between the groups in terms of the presence of hyponatremia (odds ratio (OR), 1.751; 95% confidence interval (CI), 1.020-3.005), hypokalemia (OR, 2.209; 95% CI, 1.280-3.813), central nervous system disease (OR, 2.492; 95% CI, 1.629-3.814) and/or age ⩾65 years (OR, 2.180; 95% CI, 1.242-3.826). CONCLUSIONS: The results indicated that the presence of hyponatremia or hypokalemia increases the risk of falls.

Nonrandom point defect configurations and driving force transitions for grain boundary segregation in trivalent cation doped ZrO2.

The energetically favorable spatial configuration of M(3+) ions and oxide-ion vacancies near a symmetrical grain boundary (GB) in cubic zirconia is determined for various trivalent species M(3+) (M = Al, Sc, Y, Gd, La), and the driving force for grain boundary segregation (GBS) quantitatively examined using atomistic Monte Carlo simulations in conjunction with static lattice calculations. For a high concentration of ∼10 mol %, it is found that point defects near a GB plane preferentially occupy specific sites to minimize total lattice energy, rather than being randomly distributed. Systematic analysis shows that energetically stable configurations of segregants vary depending on their ionic radii. Analysis of the driving force for GBS as a function of dopant concentration reveals that three important factors govern GBS. First, occupation of specific sites by point defects is necessary to minimize the total lattice energy; enrichment of point defects near the GB plane with random configuration does not decrease the total lattice energy significantly because of strong Coulombic interactions. Second, the factors governing GBS change with increasing dopant concentration. At dilute concentrations, relief of bond strain is the dominant factor, while at high concentrations Coulombic interactions, which depend strongly on the specific arrangement of defects, become another dominant factor. Third, the stabilization of matrix cations, Zr(4+) ions, is the dominant factor to lower the driving force for GBS at all concentrations. In contrast, the stabilization of M(3+) ions does not necessarily contribute to GBS of point defects at high concentrations. These findings suggest practical ways to control GBS to enhance materials' properties or minimize detrimental effects.

Unexpected ovarian malignancy following laparoscopic excision of adnexal masses.

STUDY QUESTION: What are the frequency of, and the prognosis for, ovarian malignancies among patients who have undergone laparoscopic surgery for an adnexal mass? SUMMARY ANSWER: The rate of unexpected ovarian malignancy resected by laparoscopy was 1.5%, and the presence of an early-stage unexpected ovarian malignancy did not alter patient prognosis. WHAT IS KNOWN ALREADY: Even when laparoscopic surgery is used for the resection of an adnexal mass that is most likely benign, some patients are found to have malignant tumors post-operatively. STUDY DESIGN, SIZE, DURATION: The pathologic reports of 884 women who underwent laparoscopic resection of an adnexal mass between May 2007 and September 2013 at the Department of Obstetrics and Gynecology of Aichi Medical University Hospital, Nagakute, Japan, were reviewed retrospectively. PARTICIPANTS/MATERIALS, SETTING, METHODS: We conducted a systematic review of the medical records of patients diagnosed post-operatively with ovarian malignancies and abstracted their demographic, clinical and pathologic data. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 1128 adnexal masses were resected, and 13 patients (1.5%) had ovarian malignancies: 6 ovarian cancer (1 mucinous, 1 endometrioid G1, 1 granulosa cell and 3 carcinoid) and 7 borderline tumors (BOTs; 5 mucinous and 2 serous). Of these, two patients with mucinous BOTs underwent fertility-sparing surgery and six patients underwent staging laparotomy. Due to cyst rupture during surgery, nine patients (69.2%) were upgraded to tumor stage IC. Secondary surgeries were performed in eight patients, with a mean interval of 88.9 days (range, 39-182 days) between the surgeries. All patients were alive and without evidence of disease at follow-up (mean follow-up, 38 months; range, 6-80 months). LIMITATIONS, REASONS FOR CAUTION: This was a retrospective study with a small case number and a short follow-up period. WIDER IMPLICATIONS OF THE FINDINGS: The presence of an early-stage unexpected ovarian malignancy did not alter the patient's prognosis, even if there was a significant delay in surgical staging after the finding of an unexpected malignancy during laparoscopy. STUDY FUNDING/COMPETING INTERESTS: No funding was obtained for this study and the authors report no conflicts of interest.

A case of disseminated nontuberculous mycobacteriosis and cerebellar toxoplasmosis with autoantibody to interferon-γ.

Autoantibody against interferon-γ has recently been associated with a variety of opportunistic infections, particularly among Asians. We report the case of a 64-year-old Japanese woman who suffered from concomitant or sequential infections of the skin, lungs, bronchi, uterus, and bladder with nontuberculous mycobacteriosis, cerebellar toxoplasmosis, measles,herpes zoster, and vulvar herpes. Blood mononuclear cells from the patient displayed intact cytokine production in response to various stimuli and interferon-γ. High-titer anti-interferon-γ autoantibodies were detected in her serum. The atypical pathology hampered early diagnosis, but indeterminate results of an interferon-γ release assay could offer a simple clue suggesting the presence of autoantibody.

Revisiting the ultra-high dose rate effect: implications for charged particle radiotherapy using protons and light ions.

OBJECTIVE: To reinvestigate ultra-high dose rate radiation (UHDRR) radiobiology and consider potential implications for hadrontherapy. METHODS: A literature search of cellular UHDRR exposures was performed. Standard oxygen diffusion equations were used to estimate the time taken to replace UHDRR-related oxygen depletion. Dose rates from conventional and novel methods of hadrontherapy accelerators were considered, including spot scanning beam delivery, which intensifies dose rate. RESULTS: The literature findings were that, for X-ray and electron dose rates of around 10(9) Gy s(-1), 5-10 Gy depletes cellular oxygen, significantly changing the radiosensitivity of cells already in low oxygen tension (around 3 mmHg or 0.4 kPa). The time taken to reverse the oxygen depletion of such cells is estimated to be over 20-30 s at distances of over 100 µm from a tumour blood vessel. In this time window, tumours have a higher hypoxic fraction (capable of reducing tumour control), so the next application of radiation within the same fraction should be at a time that exceeds these estimates in the case of scanned beams or with ultra-fast laser-generated particles. CONCLUSION: This study has potential implications for particle therapy, including laser-generated particles, where dose rate is greatly increased. Conventional accelerators probably do not achieve the critical UHDRR conditions. However, specific UHDRR oxygen depletion experiments using proton and ion beams are indicated.

Treatment of spontaneous intradural vertebral artery dissections.

Spontaneous intradural vertebral artery dissections may cause subarachnoid hemorrhage and often result in devastating damage. Increased use of noninvasive imaging studies has allowed larger numbers of patients to be diagnosed. In addition, intracranial vertebral artery dissection tends to induce multiple lesions affecting both intracranial vertebral arteries recurrently. Although unruptured dissections in this area usually have a benign nature, some authors have reported on the incidence of rupture from this lesion. Once hemorrhage from a dissecting vessel wall has occurred, it needs to be treated in the acute phase because of the high risk of rebleeding resulting in high morbidity and mortality. From December 2004 to July 2010, we managed 47 patients with spontaneous vertebral artery dissection, 31 patients were ruptured and 16 were unruptured. All patients who suffered from subarachnoid hemorrhage were treated with endovascular procedures. Most of the patients with unruptured dissection received medical therapy, but if the aneurysmal dilatation persisted or grew, surgical interventions were performed. Stenting with or without coils was deployed for 13 patients with posterior inferior cerebellar artery involvement at the site of dissection and/or were affected on the dominant side. In some patients, stenting was performed even if they were in the acute phase. For other ruptured patients, internal coil trappings were performed. Six patients died due to severe initial subarachnoid hemorrhage and one patient, who underwent stent deployment with coils for the dominant vertebral artery, with bilateral dissection continuing to the basilar artery died due to rerupture while the next additional coiling was planning. There were two cases of complications related to the intervention. During the follow-up period no bleeding occurred in any of the patients except for the previously mentioned patient. In conclusion, internal coil trapping or stent placement with or without coils was effective in preventing rebleeding of ruptured vertebral artery dissection. If the dissection is unruptured, it is necessary to detect the risk of bleeding with careful watching and when progress appears to be made, patients should be treated promptly. Stent-assisted therapy for preserving the patency of the parent artery and major branches is a promising treatment for vertebral artery dissection, even in the acute stage of subarachnoid hemorrhage. However, the risk of acute rerupture and recurrence remains even with the porous stent placement with or without coils.

High resolution, low hν photoelectron spectroscopy with the use of a microwave excited rare gas lamp and ionic crystal filters.

The need for not only bulk sensitive but also extremely high resolution photoelectron spectroscopy for studying detailed electronic structures of strongly correlated electron systems is growing rapidly. Moreover, easy access to such a capability in one's own laboratory is desirable. Demonstrated here is the performance of a microwave excited rare gas (Xe, Kr, and Ar) lamp combined with ionic crystal filters (sapphire, CaF(2), and LiF), which can supply three strong lines near the photon energy of hnyu hν=8.4, 10.0, and 11.6 eV, with the hν resolution of better than 600 µeV for photoelectron spectroscopy. Its performance is demonstrated on some materials by means of both angle-integrated and angle-resolved measurements.

Monosomy and trisomy of 15q24-qter with cleft lip and palate.

Chromosome 15 aberrations clinically present as facial dysmorphisms such as a prominent nose, low-set ears, micrognathia and a short neck; a cleft lip and palate have not been reported. This is the first reported case of de-novo terminal deletion at 15q24 with a cleft lip and palate and low-set ears. The baby boy had a complete cleft lip and palate on the left side and incomplete cleft lip and palate on the right. A chromosomal study revealed partial monosomy and trisomy of the long arm of chromosome 15, with a karyotype of 46,XY,add(15)(24q) de novo. Surgery for lip plasty was performed at 6 months old and for palate plasty at 1 year and 9 months. Both operations were uneventful, although preoperative and postoperative examinations showed high creatinine phosphokinase values. At 3 years old, mild mental retardation was observed, but his physical development was normal.

Non-invasive method to detect induction of CYP3A4 in chimeric mice with a humanized liver.

Chimeric mice with a humanized liver have been previously established by the transplantation of human hepatocytes to urokinase-type plasminogen activator/severe combined immunodeficiency mice. A non-invasive method to detect the induction of cytochrome P450 (CYP) 3A4 was evaluated in chimeric mice with a humanized liver. Dexamethasone (DEX) was used as a probe drug to detect induction; and rifampicin was used as a model drug to induce CYP3A4. Before and after rifampicin treatment (50 mg kg(-1), intraperitoneal injection once a day for 4 days) in the chimeric mice, DEX was subcutaneously injected and the urinary excretion of 6beta-hydroxydexamethason (6betaOHD) and DEX was determined. The metabolic ratio (6betaOHD/DEX) significantly increased after rifampicin treatment. Livers from the control and rifampicin-treated chimeric mice were stained immunohistolochemically with antibodies against CYP3A4 and CYP3A5. CYP3A4 and CYP3A5 were detected in the area of humanized liver, but staining was intense for CYP3A4 and very weak for CYP3A5. Only the staining of CYP3A4 was increased after rifampicin treatment. Formation of 6betaOHD by human liver microsomes was higher than that formed by mouse liver microsomes. Metabolite formation was catalysed by both CYP3A4 and CYP3A5 and the intrinsic clearance (V(max)/K(m)) by CYP3A4 was found to be 50-fold higher than that of CYP3A5. The results of the present study indicate that estimation of the changes of the urinary metabolic ratio (6betaOHD/DEX) in the chimeric mice with a humanized liver is a very useful tool for detecting the induction of CYP3A4 by a non-invasive method.

The nucleotide sequence and genome organization of Magnaporthe oryzae virus 1.

Magnaporthe oryzae virus 1 (MoV1) found in Magnaporthe oryzae, the pathogenic fungus responsible for rice blast, is a small icosahedral virus with a nonsegmented double-stranded RNA genome. The viral genome has two open reading frames (ORF 1 and 2). The deduced amino acid sequences of both ORF 1 and ORF 2 show a significant similarity to those of capsid protein and RdRp, respectively, of members of the family Totiviridae. Both a comparison of genome organization and phylogenic analysis have indicated that MoV1 is closely related to some of the totiviruses that infect filamentous fungi. These results suggest that MoV1 belongs to the family Totiviridae.

Establishment of immortalized dental follicle cells for generating periodontal ligament in vivo.

The dental follicle is a mesenchymal tissue that surrounds the developing tooth germ. During tooth root formation, periodontal components, viz., cementum, periodontal ligament (PDL), and alveolar bone, are created by dental follicle progenitors. Here, we report the presence of PDL progenitors in mouse dental follicle (MDF) cells. MDF cells were obtained from mouse incisor tooth germs and immortalized by the expression of a mutant human papilloma virus type 16 E6 gene lacking the PDZ-domain-binding motif. MDF cells expressing the mutant E6 gene (MDF( E6-EGFP ) cells) had an extended life span, beyond 150 population doublings (PD). In contrast, normal MDF cells failed to proliferate beyond 10 PD. MDF( E6-EGFP ) cells expressed tendon/ligament phenotype-related genes such as Scleraxis (Scx), growth and differentiation factor-5, EphA4, Six-1, and type I collagen. In addition, the expression of periostin was observed. To elucidate the differentiation capacity of MDF( E6-EGFP ) cells in vivo, the cells were transplanted into severe combined immunodeficiency mice. At 4 weeks, MDF( E6-EGFP ) cell transplants had the capacity to generate a PDL-like tissue that expressed periostin, Scx, and type XII collagen and the fibrillar assembly of type I collagen. Our findings suggest that MDF( E6-EGFP ) cells can act as PDL progenitors, and that these cells may be a useful research tool for studying PDL formation and for developing regeneration therapies.

CYP2A7 polymorphic alleles confound the genotyping of CYP2A6*4A allele.

Human cytochrome P450 (CYP) 2A6 metabolizes nicotine to cotinine. Genetic polymorphisms of CYP2A6 contribute to the interindividual variability of nicotine metabolism. We encountered some subjects possessing two copies of the CYP2A6 gene, although they were genotyped as heterozygotes of the CYP2A6*4A allele (entire CYP2A6 gene deleted allele). From the subjects, we found CYP2A7 polymorphic alleles (CYP2A7*1B, CYP2A7*1C, and CYP2A7*1D) in which the sequences in the 3'-flanking region were converted to the corresponding CYP2A6 sequences, being confused with the CYP2A6*4A. These allele frequencies in European-Americans (n=187) were 1.3, 2.1, 0.3%, respectively, but these were very rare in African-Americans (n=176), Japanese (n=184), and Koreans (n=209). By an improved genotyping method, the allele frequency of CYP2A6*4A of 3.7% in European-Americans was corrected to 0%. The comprehensible and reliable genotyping method developed in this study would be useful to evaluate associations between the genotype and phenotype.

Fluctuations in carotid arterial distensibility during the menstrual cycle do not influence cardiovagal baroreflex sensitivity.

AIM: Fluctuations in autonomic nervous functions throughout the menstrual cycle and the underlying mechanism concerning them are not well known. This study was designed to test the hypothesis that fluctuations in cardiovagal baroreflex sensitivity (BRS) throughout the menstrual cycles of young women are due to fluctuations in carotid arterial distensibility. METHODS: In eight eumenorrhoeic healthy young women (18-24 years), we determined the variations in the carotid arterial distensibility coefficient (DC; via simultaneous ultrasonography and applanation tonometry), cardiovagal BRS (phase IV of the Valsalva manoeuvre and the sequence method; up- or down-sequence spontaneous BRS), and serum oestradiol and progesterone concentrations at five points in the menstrual cycle (menstrual = M, follicular = F, ovulatory = O, early luteal = EL, and late luteal = LL). RESULTS: Serum oestradiol and progesterone levels were consistent with the predicted cycle phases. Carotid arterial DC fluctuated cyclically, increasing significantly from the M (52.4 +/- 4.9 x 10(-3) kPa(-1), mean +/- SE) and F (52.7 +/- 4.4) phases to the O (57.6 +/- 4.4) phase and declining sharply in the EL (46.0 +/- 4.0) and LL (45.1 +/- 3.0) phases (F = 6.37, P < 0.05). Contrary to our prediction, however, cardiovagal BRS by the Valsalva manoeuvre (P = 0.73) or sequence method (up-sequence spontaneous BRS; P = 0.84: down-sequence spontaneous BRS; P = 0.67) did not change significantly during the menstrual cycle. CONCLUSION: The results suggest that, although carotid arterial distensibility fluctuates with the changes in ovarian hormone levels that occur during the menstrual cycle, the fluctuations in carotid arterial distensibility do not influence cardiovagal BRS.

In vivo induction of human cytochrome P450 3A4 by rifabutin in chimeric mice with humanized liver.

The induction of human cytochrome P450 enzymes (CYPs) often poses a serious problem in clinical practice. The induction of CYP3A leads to a decrease in the pharmacological potency of drugs, since many drugs are substrates of CYP3A. The present study examined the in vivo induction potency of human CYP3A in chimeric mice with humanized liver, recently established in Japan, by a specific inducer of human CYP3A enzyme activity in this experimental condition, rifabutin, which is an analogue of rifampicin. The chimeric mice were treated intraperitoneally daily for 4 days with rifabutin (50 mg kg(-1) day(-1)). The mRNA, protein and enzyme activity in liver of the chimeric mice were measured by reverse-transcriptase polymerase chain reaction, Western blot analysis and high-performance liquid chromatography, respectively. In the chimeric mice, the human CYP3A4 mRNA expression, CYP3A4 protein content, testosterone 6ss-hydroxylase activity and dexamethasone 6-hydroxylase activity were increased 7.4-, 3.0-, 2.4- and 1.9-fold, respectively, by treatment with rifabutin. The mRNA expression of other human CYPs, transporters and nuclear receptors was not significantly changed by rifabutin. On the other hand, rifabutin was demonstrated not to increase the murine Cyp3a enzyme activities in the control mice. It was demonstrated that human CYP3A4 expressed in the chimeric mice with humanized liver was induced by rifabutin, suggesting that human CYP3A4 in the chimeric mice had induction potency. This chimeric mouse model may be a useful animal model to estimate and predict the in vivo induction of CYPs in human.