Large Enhancement of Thermoelectric Efficiency Due to a Pressure-Induced Lifshitz Transition in SnSe.

The Lifshitz transition, a change in Fermi surface topology, is likely to greatly influence exotic correlated phenomena in solids, such as high-temperature superconductivity and complex magnetism. However, since the observation of Fermi surfaces is generally difficult in the strongly correlated systems, a direct link between the Lifshitz transition and quantum phenomena has been elusive so far. Here, we report a marked impact of the pressure-induced Lifshitz transition on thermoelectric performance for SnSe, a promising thermoelectric material without a strong electron correlation. By applying pressure up to 1.6 GPa, we have observed a large enhancement of the thermoelectric power factor by more than 100% over a wide temperature range (10-300 K). Furthermore, the high carrier mobility enables the detection of quantum oscillations of resistivity, revealing the emergence of new Fermi pockets at ∼0.86 GPa. The observed thermoelectric properties linked to the multivalley band structure are quantitatively reproduced by first-principles calculations, providing novel insight into designing the SnSe-related materials for potential valleytronic as well as thermoelectric applications.

Thermoelectric properties of (Ba,K)Cd2As2 crystallized in the CaAl2Si2-type structure.

As-Based Zintl compounds Ba1-xKxCd2As2 crystallized in the CaAl2Si2-type structure (space group P3[combining macron]m1) were prepared using solid-state reactions followed by hot-pressing. We have successfully substituted K for Ba up to x = 0.08, producing hole-carrier doping with concentrations up to 1.60 × 1020 cm-3. We have determined the band-gap value of non-doped BaCd2As2 to be 0.40 eV from the temperature dependence of the electrical resistivity. Both the electrical resistivity and the Seebeck coefficient decrease with hole doping, leading to a power factor value of 1.28 mW m-1 K-2 at 762 K for x = 0.04. A first-principles band calculation shows that the relatively large power factor mainly originates from the two-fold degeneracy of the bands comprising As px,y orbitals and from the anisotropic band structure at the valence-band maximum. The lattice thermal conductivity is suppressed by the K doping to 0.46 W m-1 K-1 at 773 K for x = 0.08, presumably due to randomness. The effect of randomness is compensated by an increase in the electronic thermal conductivity, which keeps the total thermal conductivity approximately constant. In consequence, the dimensionless figure-of-merit ZT reaches a maximum value of 0.81 at 762 K for x = 0.04.

Effects of the ether oxygen atom in alkyl side chains on the physical properties of piperidinium ionic liquids.

Various types of piperidinium ionic liquids (ILs) equipped with an oxygen atom-containing alkyl side chain on the positively charged nitrogen atom were systematically synthesized and their physical properties investigated. The thermal stability, viscosity, electrochemical window, and ion conductivity were influenced significantly by changing the position of the oxygen atom in the alkyl chain. Although the lowest viscosity was recorded for 1-((2-methoxyethoxy)methyl)-1-methylpiperidin-1-ium bis(trifluoromethylsulfonyl)amide ([PP1MEM][Tf2N]), 1-methyl-1-(2-propoxyethyl)piperidin-1-ium bis(trifluoromethylsulfonyl)amide ([PP1PE][Tf2N]) can be recommended as the best IL as an electrolyte due to its low viscosity and high thermal and electrochemical stability among the seven ILs tested.

Mediastinoscopic extended thymectomy for pediatric patients with myasthenia gravis.

BACKGROUND: Extended thymectomy is indicated for children with myasthenia gravis (MG) when drug-resistance or dependence is seen. We have employed a technique for mediastinoscopic extended thymectomy (MET) on children with MG. METHOD: A total of 14 children underwent MET at Kanagawa Children's Medical Center between 2005 and 2013. A mediastinal operation field was made by a V-shaped hook infrasternally to extirpate the thymus with adipose tissue around the thymus. RESULTS: The operation time and the amount of blood loss were 182±44 minutes and 34±43 ml, respectively. Postoperative complications, in the form of transient paralysis of the right recurrent nerve, occurred in 2 patients. The median length of postoperative hospital stay was 4.5 days. After MET, 6 patients achieved complete remission and 7 patients achieved steroid dose reduction, but no improvement was seen in 1 patient. CONCLUSIONS: This procedure offers the advantage of good surgical access for dissection around the bilateral phrenic nerves in extended total thymectomy, while achieving good cosmetic results.

IFPA Meeting 2012 Workshop Report III: trophoblast deportation, gestational trophoblastic disease, placental insufficiency and fetal growth restriction, trophoblast over-invasion and accreta-related pathologies, placental thrombosis and fibrinolysis.

Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialized topics. At IFPA meeting 2012 there were twelve themed workshops, five of which are summarized in this report. These workshops related to various aspects of placental biology but collectively covered areas of clinical research and pregnancy disorders: 1) trophoblast deportation; 2) gestational trophoblastic disease; 3) placental insufficiency and fetal growth restriction; 4) trophoblast overinvasion and accreta-related pathologies; 5) placental thrombosis and fibrinolysis.

The application of a newly developed linear stapler preloaded with tissue reinforcement for distal pancreatectomy in the management of ovarian cancer.

Advanced ovarian cancer may extend into the spleen, and even the pancreatic tail, in which a splenectomy associated with distal pancreatectomy is crucial for optimal cytoreduction. A new linear stapler preloaded with tissue reinforcement is currently introduced. We herein report the first three cases of successful application of this device for distal pancreatectomy performed during cytoreductive surgery for ovarian cancer.

Incommensurate spin fluctuations in hole-overdoped superconductor KFe2As2.

A neutron scattering study of heavily hole-overdoped superconducting KFe2As2 revealed a well-defined low-energy incommensurate spin fluctuation at [π(1 ± 2 δ),0] with δ = 0.16. The incommensurate structure differs from the previously observed commensurate peaks in electron-doped AFe2As2 (A = Ba, Ca, or Sr) at low energies. The direction of the peak splitting is perpendicular to that observed in Fe(Te,Se) or in Ba(Fe,Co)2As2 at high energies. A band structure calculation suggests interband scattering between bands around the Γ and X points as an origin of this incommensurate peak. The perpendicular direction of the peak splitting can be understood within the framework of multiorbital band structure. The results suggest that spin fluctuation is more robust in hole-doped than in electron-doped samples, which can be responsible for the appearance of superconductivity in the heavily hole-doped samples.

The risk of post-molar gestational trophoblastic neoplasia is higher in heterozygous than in homozygous complete hydatidiform moles.

BACKGROUND: Complete hydatidiform mole (CHM) is a high-risk pregnancy for gestational trophoblastic neoplasia (GTN). Patients with CHM have a 10-30% chance of trophoblastic sequelae. CHM includes androgenic homozygous (monospermic) and androgenic heterozygous (dispermic) moles. It is controversial whether the risk of GTN is higher with heterozygous than with homozygous CHM. A prospective cohort study was conducted to assess risk of GTN in homozygous and heterozygous CHM using short tandem repeat (STR) polymorphisms, and a meta-analysis of previous reports. METHODS: Twenty-eight consecutive molar pregnancies were evacuated and followed by regular hCG measurements to detect GTN. Persistent GTN was diagnosed according to the International Federation of Gynecology and Obstetrics 2000 system. Cytogenesis of the mole was determined by STR polymorphisms of molar tissue and parental blood. A meta-analysis of the GTN rate from previous reports was conducted using Mantel-Haenszel methods. RESULTS: Of 28 molar pregnancies, 24 were homozygous and three were heterozygous CHM. The remaining mole was diandric triploidy (a partial hydatidiform mole). Of the 24 homozygous CHMs, six (25%) cases developed GTN and received chemotherapy. Meanwhile, all three cases (100%) of heterozygous mole developed GTN and needed chemotherapy. The GTN risk was higher in heterozygous (P = 0.029, Fisher's exact test) than homozygous moles. A systematic review revealed only five previous reports (with more than 15 cytogenetically diagnosed cases), and the pooled relative risk of persistent GTN for heterozygous mole was not significant (odds ratio, 2.0; 95% confidence interval, 0.98-4.07). CONCLUSIONS: Heterozygous CHM had a higher risk for GTN than homozygous CHM.

Serum YKL-40 as a marker for cervical adenocarcinoma.

BACKGROUND: The current study examined the clinical usefulness of YKL-40 in detection and prognosis of uterine cervical cancer. PATIENTS AND METHODS: Serum levels of YKL-40, cancer antigen 125 (CA 125), carbohydrate antigen 19-9 (CA19-9), and squamous cell carcinoma (SCC) antigen were determined by enzyme-linked immunosorbent assay in women with benign gynecologic disease (n=24), cervical malignancy (SCC, n=104; adenocarcinoma, n=37), and age-matched healthy controls (n=45). Immunohistochemical analysis for local YKL-40 expression was carried out on 28 adenocarcinomas. RESULTS: Receiver operating characteristic curve analysis showed that YKL-40 [area under the curve (AUC)=0.882] was significantly better at discriminating adenocarcinoma from healthy control than SCC antigen, CA 125, and CA19-9. For SCC, YKL-40 (AUC=0.898) carried out similarly to SCC antigen and was better than CA 125 and CA19-9. Using a cut-off YKL-40 value of 92.2 ng/ml, sensitivity of YKL-40 in stage I adenocarcinoma (68%) was higher than that of the other three markers (11%-21%). Tumor-associated macrophages showed immunoreactivity for YKL-40 in 2 of 28 adenocarcinoma tissue samples, but adenocarcinoma cells themselves were nonimmunoreactive in all samples. Multivariate Cox regression analysis revealed that elevated pretreatment YKL-40 levels predicted unfavorable prognosis, independent of International Federation of Gynecology and Obstetrics stage and age at diagnosis. CONCLUSIONS: Pretreatment serum YKL-40 level is a possible prognosticator of cervical adenocarcinoma.

Concurrent daily cisplatin and extended-field radiation therapy for carcinoma of the cervix.

The aim of this study was to assess acute toxicities of concurrent low-dose daily cisplatin and extended-field radiation therapy (EFRT) for carcinoma of the uterine cervix. Fifteen women with cervical cancer who were treated with concurrent daily low-dose cisplatin and EFRT were analyzed. Daily cisplatin dose was fixed to 8 mg/m(2), which was determined in the preceding phase I study using pelvic radiotherapy. Twelve patients underwent either combined external beam radiation therapy and intracavitary brachytherapy or external beam radiation therapy alone. Three other patients were treated with adjuvant chemoradiotherapy after surgery. A total dose of EFRT ranged from 40 to 45 Gy, with an additional boost to the gross tumor volume up to 50.4-55 Gy. A median total dose of cisplatin during entire radiation therapy course was 224 mg/m(2) (range, 200-240 mg/m(2)). In 14 of 15 patients (93%), daily cisplatin could be delivered continuously as planned without any modification. Administration of cisplatin had to be interrupted in only one patient for only 3 days. Fourteen patients developed grade 2 or worse leukopenia including five after treatment, grade 2 in four, grade 3 in eight, and grade 4 in two. Grade 3 thrombocytopenia was observed in three patients. Grade 2 or worse anemia was observed in 12. Three patients had grade 3 nonhematologic toxicities, diarrhea in two, and nausea/vomiting in one. Although moderate to severe hematologic toxicities are common, this study suggests that concurrent low-dose daily cisplatin and EFRT are feasible. A cumulative cisplatin dose of greater than 200 mg/m(2) during radiation therapy could be achieved by using daily cisplatin dose of 8 mg/m(2).

Erythromycin ameliorates renal injury via anti-inflammatory effects in experimental diabetic rats.

AIMS/HYPOTHESIS: Recent studies have shown that the inflammatory process is involved in the pathogenesis of diabetic nephropathy. Fourteen-membered ring macrolides, including erythromycin, have anti-inflammatory, as well as antibacterial effects. The aim of this study was to investigate the renoprotective effects of erythromycin in streptozotocin (STZ)-induced diabetic rats. METHODS: STZ-induced diabetic rats were treated orally with erythromycin (5 mg/kg body weight) or vehicle every day for 8 weeks. To evaluate the effect of erythromycin treatment, we measured urinary albumin excretion, and examined the following in the kidney: histological changes, the expression of intercellular adhesion molecule-1 (ICAM-1), macrophage infiltration, and nuclear factor-kappa B (NF-kappaB) activity. RESULTS: Erythromycin significantly reduced urinary albumin excretion without affecting blood glucose levels and blood pressure. Erythromycin also attenuated glomerular hypertrophy, mesangial expansion, macrophage infiltration and ICAM-1 expression in renal tissues. The expression of the gene encoding TGFB1 (also known as TGF-beta1), type IV collagen protein production and NF-kappaB activity in renal tissues were increased in diabetic rats and reduced by erythromycin treatment. CONCLUSIONS/INTERPRETATION: Erythromycin prevented renal injuries without changes of blood glucose levels and blood pressure in experimental diabetic rats. These results suggest that the renoprotective effects of erythromycin are based on its anti-inflammatory effect via suppression of NF-kappaB activation. Modulation of microinflammation with erythromycin may provide a new approach for diabetic nephropathy.

Cerebral ischaemia during cardiac surgery in children detected by combined monitoring of BIS and near-infrared spectroscopy.

BACKGROUND: Children frequently suffer transient cerebral ischaemia during cardiac surgery. We measured cerebral ischaemia in children during cardiac surgery by combining two methods of monitoring. METHODS: We studied 65 children aged between 5 months and 17 yr having surgery to correct non-cyanotic heart disease using hypothermic cardiopulmonary bypass (CPB). During surgery, we measured the Bispectral Index (BIS) and regional cerebral haemoglobin oxygen saturation (SrO2) with near-infrared spectroscopy (NIRS). Cerebral ischaemia was diagnosed if both SrO2 and BIS decreased abruptly when acute hypotension occurred. In each patient, the relationship between SrO2 and arterial blood pressure (AP) was indicated by a plot of mean SrO2 against simultaneous mean AP. RESULTS: We noted 72 episodes of cerebral ischaemia in 38 patients. Sixty-three ischaemic events were during CPB. Cerebral ischaemia was less frequent in older patients. Cerebral ischaemia was more common and more frequent in children under 4 yr old. Haematocrit during CPB was lower and SrO2 was more dependent on AP in children under 4 yr. CONCLUSIONS: Children less than 4 yr of age are more likely to have cerebral ischaemia caused by hypotension during cardiac surgery. Ineffective cerebral autoregulation and haemodilution during CPB may be responsible.

Anti-analgesic activity of enterostatin (VPDPR) is mediated by corticosterone.

Although enterostatin (VPDPR) inhibited morphine-induced analgesia, it had no affinity for mu-opioid receptors. VPDPR administration was reported to elevate serum corticosterone levels. We found that corticosterone exhibited a similar anti-analgesic effect selective for mu-opioid. Furthermore, the anti-analgesic effect of VPDPR was inhibited by RU486, an antagonist for the glucocorticoid receptor. The anti-analgesic effect of VPDPR was not observed in adrenalectomized mice. These results suggest that the anti-analgesic activity of VPDPR is mediated by corticosterone released from the adrenal cortex.

Roentgenographic evaluation of ossification and calcification of the lumbar spinal canal after intradiscal betamethasone injection.

There have been reports of lumbar spinal canal ossification and calcification after triamcinolone intradiscal injection therapy. Our objective was to observe the roentgenographic changes after betamethasone intradiscal injection therapy for lumbar disc diseases. The subjects were 183 patients (498 discs; 130 men and 53 women) who underwent discography and betamethasone intradiscal injection therapy and were followed for a mean of 5 years and 7 months. Ossification and calcification appeared de novo (three patients, three discs) or enlarged (four patients, five discs) in the outer layer of the posterior annulus fibrosus or posterior longitudinal ligament in eight discs among seven patients (3.8%). The incidence and degree of ossification and calcification in our patients were significantly lower than those reported in previous studies, and a long time elapsed before ossification and calcification appeared or enlarged. Intradiscal injection of betamethasone did not appear to confer any incremental relative risk for lumbar spinal canal ossification and calcification based on review of follow-up roentgenographs.

Insulin receptor substrate protein p53 localization in rats suggests mechanism for specific polyglutamine neurodegeneration.

Dentatorubral-pallidoluysian atrophy (DRPLA) is a neurodegenerative disease that results from the expansion of an unstable CAG repeat within the coding regions of the DRPLA gene. Recently it was shown that the DRPLA gene product, atrophin-1, interacts with the human insulin receptor tyrosine kinase substrate protein, IRSp53. We have isolated rat and mouse cDNA clones for IRSp53 and determined expression patterns in rat central nervous system. In situ hybridization analysis revealed enriched IRSp53 mRNA expression in rat forebrain structures, including the cerebral cortex (layers II/III, V and VI), striatum, hippocampus and olfactory bulb. IRSp53 hybridization signals were also detected in the cerebellum, subthalamic nucleus, pons, amygdala and hypothalamus. These findings support the idea that insulin and insulin growth factor-1 have a role in neurotransmission, one that is regionally specific. The expression of IRSp53 in regions similar to those that degenerate in DRPLA supports the notion that IRSp53 is a relevant atrophin-1 binding protein and may provide a mechanism for region-specific neurodegeneration.

Crystallization and preliminary X-ray analysis of catalase-peroxidase from the halophilic archaeon Haloarcula marismortui.

Catalase-peroxidases are bifunctional enzymes found in many microorganisms. Crystals of catalase-peroxidase from the halophilic archaeon Haloarcula marismortui were obtained using the hanging-drop vapour-diffusion method. The rhombic plate-shaped crystals were grown from purified protein solution using (NH(4))(2)SO(4) as precipitant at 293 K. The crystal belongs to the monoclinic system, space group C2, and diffracted beyond 2.0 A resolution.

Depressed myocardial fatty acid metabolism in patients with muscular dystrophy.

Myocardial involvement is frequently associated with various types of muscular dystrophy and Thallium-201 scintigraphy can show regional myocardial perfusion abnormalities in patients with muscular dystrophy. Myocardial fatty acid metabolism can now be imaged using a radioiodinated branched fatty acid (123I-BMIPP). The present study evaluates myocardial fatty acid metabolism in muscular dystrophy. Twenty-eight patients underwent 123I-BMIPP(BMIPP) and Thallium dual single photon emission tomography. Regional uptake of both tracers was visually analyzed. We also assessed electrocardiography and echocardiography. The results showed that the BMIPP uptake compared to Thallium was smaller in 57% of all patients. BMIPP SPECT images revealed abnormalities in four of eight patients with a normal electrocardiogram. Abnormal BMIPP uptake with normal regional wall motion was evident in nine patients. The size of the region with defective BMIPP uptake was larger than that of asynergic areas detected by echocardiography in 11 patients. In conclusion, muscular dystrophy involves depressed myocardial fatty acid metabolism in larger extent of region than that in perfusion or mechanical abnormality.

Fission yeast homologues of the B' subunit of protein phosphatase 2A: multiple roles in mitotic cell division and functional interaction with calcineurin.

BACKGROUND: Protein phosphatase 2A (PP2A) is a serine/threonine phosphatase distributed in eukaryotes from yeast to human, and plays pivotal roles in diverse cellular functions such as metabolism, cell cycle progression, gene expression and development. PP2A holoenzyme is a heterodimer of a catalytic subunit C and a regulatory subunit A, or a heterotrimer of C, A and a variable regulatory subunit consisting of three families; B, B', and PR72. Specific functions for each variable subunit are not well understood. RESULTS: Two fission yeast genes pbp1+ and pbp2+ homologous to the regulatory subunit B' were isolated. Physical in vivo interaction of the gene products with the catalytic subunit was demonstrated. A double disruption haploid mutant (Deltapbp1Deltapbp2) showed growth defect, cell shape and size abnormality, multiseptation and anucleated cell formation due to abnormality in septum positioning. These phenotypes were suppressed by human B' cDNA, indicating the striking conservation of the B' function from yeast to human. Over-expression of fission yeast B' led to growth defects, a loss of cell shape polarity, septal abnormality and anucleated cell formation. Deltapbp1Deltapbp2 and pbp1 null haploids were hypersensitive to calcineurin inhibitors, cyclosporin A and FK506, with which the mutants underwent arrest at post-anaphase and cell lysis. Double disruption of calcineurin and pbp1+, but not pbp2+, genes led to synthetic lethality. CONCLUSION: The fission yeast B' subunit of PP2A plays critical roles in cell shape control and septum formation, and shares essential functions with calcineurin for viability, possibly through their roles in cytokinesis and cell wall integrity.