Spectroscopic evidence for negative electronic compressibility in a quasi-three-dimensional spin-orbit correlated metal

Negative compressibility is a sign of thermodynamic instability of open or non-equilibrium systems. In quantum materials consisting of multiple mutually coupled subsystems, the compressibility of one subsystem can be negative if it is countered by positive compressibility of the others. Manifestations of this effect have so far been limited to low-dimensional dilute electron systems. Here, we present evidence from angle-resolved photoemission spectroscopy (ARPES) for negative electronic compressibility (NEC) in the quasi-three-dimensional (3D) spin-orbit correlated metal (Sr1-xLax)3Ir2O7. Increased electron filling accompanies an anomalous decrease of the chemical potential, as indicated by the overall movement of the deep valence bands. Such anomaly, suggestive of NEC, is shown to be primarily driven by the lowering in energy of the conduction band as the correlated bandgap reduces. Our finding points to a distinct pathway towards an uncharted territory of NEC featuring bulk correlated metals with unique potential for applications in low-power nanoelectronics and novel metamaterials.

Vascular Functional and Morphological Alterations in Smokers during Varenicline Therapy

BACKGROUND

Varenicline has been reported to achieve high rates of smoking cessation. It remains undetermined whether varenicline therapy improves vascular function in smokers.

METHODS

Consecutive Seventy-two smokers (age 57 ± 12 years) who succeeded in complete smoking cessation and 46 normal healthy volunteers (age 24 ± 3 years) with no cardiovascular risk factors were enrolled into this study. Vascular function and structure were assessed by flow-mediated dilation (FMD), nitroglycerin-induced vasodilation, and brachial artery intima-media thickness (baIMT) at baseline and 20 weeks after the initiation of varenicline therapy in smokers. FMD and baIMT were measured simultaneously using a semi-automatic vessel wall-tracking software program. 75 μg dose of a nitroglycerin tablet were sublingually administered for the nitroglycerin-induced vasodilation measurement.

RESULTS

Exhaled-carbon monoxide concentration decreased significantly (20.0 ± 11.1 ppm at baseline vs 1.9 ± 1.5 ppm after 20 weeks, p < 0.001). FMD was significantly improved after 20 weeks (4.09% ± 1.83% at baseline vs 4.77% ± 2.33% after 20 weeks, p = 0.010), whereas nitroglycerin-induced vasodilation and baIMT were not significantly changed.

CONCLUSIONS

Smoking cessation with varenicline therapy significantly increased FMD without significant changes of nitroglycerin-induced vasodilation or baIMT from baseline to 20 weeks. It appears to improve vascular function in smokers, which depends on endothelial function rather than on vascular smooth muscle function or changes in vascular structure.

Fluency-dependent cortical activation associated with speech production and comprehension in second language learners

This functional magnetic resonance imaging (fMRI) study investigated the brain regions underlying language task performance in adult second language (L2) learners. Specifically, we identified brain regions where the level of activation was associated with L2 fluency levels. Thirty Japanese-speaking adults participated in the study. All participants were L2 learners of English and had achieved varying levels of fluency, as determined by a standardized L2 English proficiency test, the Versant English Test (Pearson Education Inc., 2011). When participants performed the oral sentence building task from the production tasks administered, the dorsal part of the left inferior frontal gyrus (dIFG) showed activation patterns that differed depending on the L2 fluency levels: The more fluent the participants were, the more dIFG activation decreased. This decreased activation of the dIFG might reflect the increased automaticity of a syntactic building process. In contrast, when participants performed an oral story comprehension task, the left posterior superior temporal gyrus (pSTG) showed increased activation with higher fluency levels. This suggests that the learners with higher L2 fluency were actively engaged in post-syntactic integration processing supported by the left pSTG. These data imply that L2 fluency predicts neural resource allocation during language comprehension tasks as well as in production tasks. This study sheds light on the neural underpinnings of L2 learning by identifying the brain regions recruited during different language tasks across different modalities (production vs. comprehension).

Phase III study comparing oxaliplatin plus S-1 with cisplatin plus S-1 in chemotherapy-naïve patients with advanced gastric cancer

BACKGROUND

We evaluated the efficacy and safety of S-1 plus oxaliplatin (SOX) as an alternative to cisplatin plus S-1 (CS) in first-line chemotherapy for advanced gastric cancer (AGC).

PATIENTS AND METHODS

In this randomized, open-label, multicenter phase III study, patients were randomly assigned to receive SOX (80-120 mg/day S-1 for 2 weeks with 100 mg/m(2) oxaliplatin on day 1, every 3 weeks) or CS (S-1 for 3 weeks with 60 mg/m(2) cisplatin on day 8, every 5 weeks). The primary end points were noninferiority in progression-free survival (PFS) and relative efficacy in overall survival (OS) for SOX using adjusted hazard ratios (HRs) with stratification factors; performance status and unresectable or recurrent (+adjuvant chemotherapy) disease.

RESULTS

Overall, 685 patients were randomized from January 2010 to October 2011. In per-protocol population, SOX (n = 318) was noninferior to CS (n = 324) in PFS [median, 5.5 versus 5.4 months; HR 1.004, 95% confidence interval (CI) 0.840-1.199; predefined noninferiority margin 1.30]. The median OS for SOX and CS were 14.1 and 13.1 months, respectively (HR 0.958 with 95% CI 0.803-1.142). In the intention-to-treat population (SOX, n = 339; CS, n = 337), the HRs in PFS and OS were 0.979 (95% CI 0.821-1.167) and 0.934 (95% CI 0.786-1.108), respectively. The most common ≥grade 3 adverse events (SOX versus CS) were neutropenia (19.5% versus 41.8%), anemia (15.1% versus 32.5%), hyponatremia (4.4% versus 13.4%), febrile neutropenia (0.9% versus 6.9%), and sensory neuropathy (4.7% versus 0%).

CONCLUSION

SOX is as effective as CS for AGC with favorable safety profile, therefore SOX can replace CS.

CLINICAL TRIAL NUMBER

JapicCTI-101021.

Revisit to diffraction anomalous fine structure

The diffraction anomalous fine structure (DAFS) method that is a spectroscopic analysis combined with resonant X-ray diffraction enables the determination of the valence state and local structure of a selected element at a specific crystalline site and/or phase. This method has been improved by using a polycrystalline sample, channel-cut monochromator optics with an undulator synchrotron radiation source, an area detector and direct determination of resonant terms with a logarithmic dispersion relation. This study makes the DAFS method more convenient and saves a large amount of measurement time in comparison with the conventional DAFS method with a single crystal. The improved DAFS method has been applied to some model samples, Ni foil and Fe3O4 powder, to demonstrate the validity of the measurement and the analysis of the present DAFS method.

Outcomes of immediate perforator flap reconstruction after skin-sparing mastectomy following neoadjuvant chemotherapy

BACKGROUND

The impact of neoadjuvant chemotherapy (NACT) on immediate free flap breast reconstruction remains controversial. Furthermore, the oncological outcomes of immediate free flap breast reconstruction after skin-sparing mastectomy (SSM) following NACT remain unclear. This study aimed to investigate the surgical complications and oncological outcomes of immediate perforator flap reconstruction after SSM following NACT.

METHODS

A total of 201 consecutive patients with indications for immediate perforator flap reconstruction after SSM were included between 2004 and 2012. Surgical and oncological outcomes were compared between patients with and without NACT.

RESULTS

There were 38 patients in the NACT group and 163 in the non-NACT control group. The median age of the NACT group was 39.5 years, which was significantly younger than the control group (43.0 years; P < 0.05). Patients in the NACT group also had more advanced and aggressive disease (P < 0.05). There was no significant difference in the frequency of surgical complications between the groups, no difference in the type of complications, and no significant difference in the frequencies of major and minor complications. No patients in the NACT group had delayed adjuvant therapy. Eight patients (4%) developed recurrences, with a median follow-up time of 3.0 years. Local recurrences occurred in three control patients but no patients in the NACT group.

CONCLUSION

NACT does not affect short-term or interim outcomes after immediate perforator flap reconstruction and may thus represent a safe and practical treatment option for the multidisciplinary treatment of breast cancer.

Comprehensive data on ionising radiation from Fukushima Daiichi nuclear power plant in the town of Miharu, Fukushima Prefecture: The Misho Project

Data related to radioactivity released from the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident on 15 March 2011 gathered by residents of Miharu, Fukushima Prefecture, and by Tohoku University are presented. These data sets consist of (1) the earliest radiation monitoring by a Geiger counter in the town, (2) ratios of radioactivity between (132)Te and (137)Cs for a wide area between Fukushima and Tokyo, (3) radiation measurement of soil samples collected from 18 school grounds, and (4) external radiation exposure of 1400 students using OSL badges. By combining and analysing these various data sets, a curve for the cumulative total external exposure as a function of time, with 16 : 00 h on 15 March 2011 being time zero, is obtained. The average cumulative external dosage is estimated to be 10 mSv (σ = 4.2 mSv) over 10 years. In addition, the initiative that the residents of Miharu took in response to the FDNPP accident, which became known as The Misho Project (MP), is documented; in particular, the time at which the municipality instructed the immediate ingestion of iodine tablets by those under the age of 40, 13 : 00 h on 15 March 2011, is assessed.

Remote ischemic conditioning improves coronary microcirculation in healthy subjects and patients with heart failure

BACKGROUND

Remote ischemic conditioning (RIC) is a treatment modality that suppresses inflammation and improves endothelial function, which are factors involved in the pathogenesis of heart failure (HF) with reduced left ventricular ejection fraction. Coronary flow reserve (CFR) is a physiological index of coronary microcirculation and is noninvasively measured by transthoracic Doppler echocardiography (TTDE). This study aimed to investigate the effects of RIC on CFR in healthy subjects and patients with HF, through the assessment by TTDE.

METHODS

Ten patients with HF with left ventricular ejection fraction of less than 40%, and ten healthy volunteers were enrolled in this study. RIC treatment was performed twice a day for 1 week. Our custom-made RIC device was programmed to automatically conduct 4 cycles of 5 minutes inflation and 5 minutes deflation of a blood pressure cuff to create intermittent arm ischemia. CFR measurements and laboratory tests were examined before, and after 1 week of RIC treatment.

RESULTS

One week of RIC treatment was well tolerated in both groups. RIC treatment increased CFR from 4.0 ± 0.9 to 4.6 ± 1.3 (mean ± standard deviation) in healthy subjects (P=0.02), and from 1.9 ± 0.4 to 2.3 ± 0.7 in patients with HF (P = 0.03), respectively. Systolic blood pressure in healthy subjects, and heart rate in HF patients decreased after RIC treatment (both P<0.01).

CONCLUSION

This study demonstrated that a 1 week course of RIC treatment improved coronary microcirculation in healthy subjects and patients with HF associated with reduced left ventricular ejection fraction.

Evidence of topological surface state in three-dimensional Dirac semimetal Cd3As2

The three-dimensional topological semimetals represent a new quantum state of matter. Distinct from the surface state in the topological insulators that exhibits linear dispersion in two-dimensional momentum plane, the three-dimensional semimetals host bulk band dispersions linearly along all directions. In addition to the gapless points in the bulk, the three-dimensional Weyl/Dirac semimetals are also characterized by "topologically protected" surface state with Fermi arcs on their surface. While Cd3As2 is proposed to be a viable candidate of a Dirac semimetal, more investigations are necessary to pin down its nature. In particular, the topological surface state, the hallmark of the three-dimensional semimetal, has not been observed in Cd3As2. Here we report the electronic structure of Cd3As2 investigated by angle-resolved photoemission measurements on the (112) crystal surface and detailed band structure calculations. The measured Fermi surface and band structure show a good agreement with the band structure calculations with two bulk Dirac-like bands approaching the Fermi level and forming Dirac points near the Brillouin zone center. Moreover, the topological surface state with a linear dispersion approaching the Fermi level is identified for the first time. These results provide experimental indications on the nature of topologically non-trivial three-dimensional Dirac cones in Cd3As2.

Percutaneous carbon dioxide treatment using a gas mist generator enhances the collateral blood flow in the ischemic hindlimb

AIM

Highly concentrated carbon dioxide (CO2) is thought to be useful for ischemic diseases. We investigated whether treatment with a few micrometers of CO2 molecules atomized via two fluidnozzles (CO2 mist) exerts an angiogenic effect in a mouse ischemic hindlimb model.

METHODS

Mice with unilateral hindlimb ischemia were divided into untreated (UT), 100% CO2 gas alone-treated (CG), mixed air (O2; 20%, N2; 80%) mist-treated (AM) and 100% CO2 mist-treated (CM) groups. The lower body of the mice was encased in a polyethylene bag filled with each gaseous agent using a gas mist generator for 10 minutes daily.

RESULTS

According to a laser Doppler analysis, the ischemic hindlimb blood flow was persistently higher after the seventh day of induction of ischemia in the CM group than in the UT group. The capillary density was also greater in the CM group on day 28 compared with that observed in the UT group. In addition, the parameters in the AM and CG groups were similar to those obtained in the UT group. The observed effects were abolished by the administration of an inhibitor of nitric oxide synthase (NOS). The vascular endothelial growth factor mRNA expression and protein levels and the phosphorylated endothelial NOS level were increased in the CM group compared with that observed in the UT group. A proteomic analysis using liquid chromatography-tandem mass spectrometry identified novel protein candidates regulated by CO2 mist.

CONCLUSION

Percutaneous CO2 mist therapy may be useful for treating ischemia-induced angiogenesis.

DPP-4 inhibitor and alpha-glucosidase inhibitor equally improve endothelial function in patients with type 2 diabetes: EDGE study

BACKGROUND

Alpha glucosidase inhibitor (GI) attenuates postprandial hyperglycemia (PPH) and reduces the risk of cardiovascular events in patients with impaired glucose tolerance or type 2 diabetes. Dipeptidyl peptidase 4 (DPP-4) inhibitors also attenuate PPH. PPH is one of the factors leading to endothelial dysfunction which is an early event in the pathogenesis of atherosclerosis. Furthermore, DPP-4 inhibitors protect endothelial function through a GLP-1-dependent mechanism. However, the impact of these two types of drugs on endothelial dysfunction in patients with type 2 diabetes has not been fully elucidated. We compared the effects of sitagliptin, a DPP-4 inhibitor, and voglibose, an alpha GI, on endothelial function in patients with diabetes.

METHODS

We conducted a randomized prospective multicenter study in 66 patients with type 2 diabetes who did not achieve the treatment goal with sulfonylurea, metformin or pioglitazone treatment; 31 patients received sitagliptin treatment and 35 patients, voglibose treatment. The flow-mediated dilatation (FMD) of the brachial artery was measured in the fasting state at baseline and after 12 weeks of treatment. The primary endpoint was a change in FMD (ΔFMD) from the baseline to the end of follow-up. The effects of sitagliptin and voglibose on FMD were assessed by ANCOVA after adjustment for the baseline FMD, age, sex, current smoking, diabetes duration and body mass index. Secondary efficacy measures included changes in HbA1c, GIP, GLP-1, C-peptide, CD34, lipid profile, oxidative stress markers, inflammatory markers and eGFR and any adverse events.

RESULTS

ΔFMD was significantly improved after 12 weeks of treatment in both groups, and there was no significant difference in ΔFMD between the two groups. There were no significant differences in changes in HbA1c, GIP, GLP-1, C-peptide, lipid profile, oxidative stress marker, inflammatory marker and eGFR between the two groups. Compared with voglibose, sitagliptin significantly increased the circulating CD34, a marker of endothelial progenitor cells. Adverse events were observed in 5 patients in only the voglibose group (diarrhea 1, nausea 1, edema 2 and abdominal fullness 1).

CONCLUSIONS

Sitagliptin improved endothelial dysfunction just as well as voglibose in patients with type 2 diabetes. Sitagliptin had protective effects on endothelial function without adverse events.

TRIAL REGISTRATION

registered at http://www.umin.ac.jp/ctrj/ under UMIN000003951.

Right portal vein embolization with absolute ethanol in major hepatic resection for hepatobiliary malignancy

BACKGROUND

This study aimed to evaluate the safety and efficacy of preoperative right portal vein embolization (PVE) with absolute ethanol in patients with hepatobiliary malignancies.

METHODS

PVE was performed via a percutaneous transhepatic ipsilateral approach, and the right portal branch was embolized with absolute ethanol. Technical success and complications following PVE, and changes in liver enzyme levels were evaluated. Changes in future liver remnant (FLR) and FLR/total functional liver volume ratio were calculated. Complications following hepatic resection were assessed.

RESULTS

A total of 83 patients with hepatobiliary malignancies (53 men, 30 women; mean age 68 years) underwent right PVE. Tumour types were hilar cholangiocarcinoma (37), liver metastases (14), gallbladder cancer (13), intrahepatic cholangiocellular carcinoma (10) and hepatocellular carcinoma (HCC) (9). PVE was performed successfully in all patients. Four patients (5 per cent) developed complications following PVE (liver abscess 2, left portal vein thrombosis 1, pseudoaneurysm 1), but this did not preclude hepatic resection. Liver enzyme levels rose transiently after PVE. The mean FLR and FLR/total functional liver volume increased after PVE (from 366 to 513 cm(3) and from 31 to 43 per cent respectively; both P < 0·001). Changes in the FLR and FLR/total functional liver volume ratio were comparable between patients with HCC and those with other malignancies (42 and 44 per cent, and 12 and 12 per cent, respectively). Sixty-nine of 83 patients underwent hepatic resection at a median of 25 days after PVE, with no postoperative mortality.

CONCLUSION

Preoperative right PVE with absolute ethanol is safe and effective for induction of selective hepatic hypertrophy in patients with hepatobiliary malignancy.

Arthroscopic debridement in the treatment of patients with osteoarthritis of the elbow, based on computer simulation

We retrospectively assessed the value of identifying impinging osteophytes using dynamic computer simulation of CT scans of the elbow in assisting their arthroscopic removal in patients with osteoarthritis of the elbow. A total of 20 patients were treated (19 men and one woman, mean age 38 years (19 to 55)) and followed for a mean of 25 months (24 to 29). We located the impinging osteophytes dynamically using computerised three-dimensional models of the elbow based on CT data in three positions of flexion of the elbow. These were then removed arthroscopically and a capsular release was performed.

The mean loss of extension improved from 23° (10° to 45°) pre-operatively to 9° (0° to 25°) post-operatively, and the mean flexion improved from 121° (80° to 140°) pre-operatively to 130° (110° to 145°) post-operatively. The mean Mayo Elbow Performance Score improved from 62 (30 to 85) to 95 (70 to 100) post-operatively. All patients had pain in the elbow pre-operatively which disappeared or decreased post-operatively. According to their Mayo scores, 14 patients had an excellent clinical outcome and six a good outcome; 15 were very satisfied and five were satisfied with their post-operative outcome.

We recommend this technique in the surgical management of patients with osteoarthritis of the elbow.

Cite this article: Bone Joint J 2014;96-B:237–41.

Association of a single nucleotide polymorphism in the SH2D1A intronic region with systemic lupus erythematosus

SH2D1A, also known as signaling lymphocytic activation molecule (SLAM)-associated protein (SAP), is an adaptor protein. Recently, it was reported that SAP deficient mice were protected from systemic lupus erythematosus (SLE). In this study, we postulated SH2D1A gene to be a candidate susceptibility gene for SLE and analyzed its association with SLE. A case-control association study was conducted on 5 tag single nucleotide polymorphisms (SNPs) in SH2D1A region in 506 Japanese female SLE patients and 330 healthy female controls. The luciferase assay was performed to determine the functional role of the SNP associated with SLE. One SNP in the intron 2, rs2049995, showed association with SLE (p=0.0110, odds ratio (OR) 1.97, 95% confidence interval (CI) 1.16-3.34, under the dominant model). The association of rs2049995 seemed to be stronger in the subset with the age of onset less than 20 years (p=0.0067, OR 2.65, 95% CI 1.28-5.46). Functional evaluation of rs2049995 showed that reporter gene activity was increased 1.9-fold for the susceptible allele compared with the resistant allele. An intronic SNP of SH2D1A is associated with SLE.

Hemoadsorption of high-mobility group box chromosomal protein 1 using a column for large animals

BACKGROUND

High-mobility group box chromosomal protein 1 (HMGB1) has recently been identified as an important mediator of various kinds of acute and chronic inflammation. A method for efficiently removing HMGB1 from the systemic circulation could be a promising therapy for HMGB1-mediated inflammatory diseases.

MATERIALS AND METHODS

In this study, we produced a new adsorbent material by chemically treating polystyrene fiber. We first determined whether the adsorbent material efficiently adsorbed HMGB1 in vitro using a bovine HMGB1 solution and a plasma sample from a swine model of acute liver failure. We then constructed a column by embedding fabric sheets of the newly developed fibers into a cartridge and tested the ability of the column to reduce plasma HMGB1 levels during a 4-hour extracorporeal hemoperfusion in a swine model of acute liver failure.

RESULTS

The in vitro adsorption test of the new fiber showed high performance for HMGB1 adsorption (96% adsorption in the bovine HMGB1 solution and 94% in the acute liver failure swine plasma, 2 h incubation at 37°C; p < 0.05 vs. incubation with no adsorbent). In the in vivo study, the ratio of the HMGB1 concentration at the outlet versus the inlet of the column was significantly lower in swine hemoperfused with the newly developed column (53 and 61% at the beginning and end of perfusion, respectively) than in those animals hemoperfused with the control column (94 and 93% at the beginning and end of perfusion, respectively; p < 0.05). Moreover, the normalized plasma level of HMGB1 was significantly lower during perfusion with the new column than with the control column (p < 0.05 at 1, 2, and 3 h after initiation of perfusion).

CONCLUSION

These data suggest that the newly developed column has the potential to effectively adsorb HMGB1 during hemoperfusion in swine.

Diagnostic accuracy of transthoracic and transesophageal echocardiography for the diagnosis of bicuspid aortic valve: comparison with operative findings

BACKGROUND

Bicuspid aortic valve (BAV) is associated with an increased risk of aortic valve (AV) dysfunction, aortic dissection, and infective endocarditis. Therefore, its accurate diagnosis is critical. The morphological features of AVs are generally evaluated by transthoracic echocardiography (TTE) or transesophageal echocardiography (TEE), however, the difference in the diagnostic capability of these imaging modalities for detecting BAV remains unclear. Here, we compared these 2 methods to determine their accuracy, and to clarify each role in the diagnosis of BAV.

METHODS

This blind study evaluated 126 patients (age, 70.3 +/- 7.8 years) who subsequently underwent AV replacement. The number of AV cusps of each patient was estimated by TTE and TEE and compared to the number of AV written in the operative record. Patients with poor echocardiographic images were not excluded.

RESULTS

Surgical findings showed 97 tricuspid AVs and 29 BAVs. The sensitivity, specificity, and accuracy for the diagnosis of BAV were 61%, 81%, and 77%, respectively, for TTE and 86%, 90%, and 89%, respectively, for TEE. The accuracy of TEE was significantly higher than that of TTE (p = 0.016). In non-calcified AVs, the accuracy of TTE was similar to that of TEE (96%, each) whereas in calcified AVs, TTE had a lower accuracy than TEE (72% vs 87%, p = 0.011). The feasibility was significantly higher for TEE than for TTE (98% vs 90%, p = 0.003).

CONCLUSIONS

TEE provides higher accuracy and feasibility than TTE in the diagnosis of BAV, and it should therefore be indicated when morphological features of AVs cannot be evaluated by TTE.