Spectroscopic Evidence for Electron-Boson Coupling in Electron-Doped Sr_{2}IrO_{4}

The pseudogap, d-wave superconductivity and electron-boson coupling are three intertwined key ingredients in the phase diagram of the cuprates. Sr_{2}IrO_{4} is a 5d-electron counterpart of the cuprates in which both the pseudogap and a d-wave instability have been observed. Here, we report spectroscopic evidence for the presence of the third key player in electron-doped Sr_{2}IrO_{4}: electron-boson coupling. A kink in nodal dispersion is observed with an energy scale of ∼50  meV. The strength of the kink changes with doping, but the energy scale remains the same. These results provide the first noncuprate platform for exploring the relationship between the pseudogap, d-wave instability, and electron-boson coupling in doped Mott insulators.

Simple dose-escalation regimen for hydroxychloroquine-induced hypersensitivity reaction in patients with systemic lupus erythematosus enabled treatment resumption

OBJECTIVE

This study aimed to investigate the risk factors of hydroxychloroquine (HCQ)-induced hypersensitivity in patients with systemic lupus erythematosus (SLE) and to propose a simple dose-escalation regimen in cases of mild HCQ-induced hypersensitivity.

METHODS

We identified patients with SLE who started HCQ between 2009 and 2018 and cases of HCQ-induced hypersensitivity by reviewing the electronic medical charts. A simple dose-escalation regimen, starting at 40 mg/day with weekly increments of 40 mg/day to 200 mg/day, was used in patients with HCQ-induced hypersensitivity who did not require hospitalization or systemic steroid therapy. We then compared the clinical parameters of patients with and without HCQ-induced hypersensitivity and evaluated the success of our dose-escalation regimen.

RESULTS

We enrolled 302 patients with SLE and identified 25 cases of HCQ-induced eruption (8.3%). The mean Naranjo score of these patients was 5.1 ± 1.4 (min 3, max 8), and all 25 patients received a 'possible' (9) or 'probable' (16) score. A mild, generalized, maculopapular rash occurred in 24 patients, and urticaria occurred in one patient at 24 days (interquartile range 15-40 days) after the start of treatment. The proportion of cyclophosphamide use, glucocorticoid consisting of prednisolone 20 mg/day or more, and initiation of SMX-TMP within 28 days were higher in patients with skin eruptions. On multivariate analysis, only cyclophosphamide use was identified as a risk factor of HCQ-induced hypersensitivity (odds ratio = 12.3 (95% confidential interval 1.4-14.3)). Thirteen of the 14 patients on the dose-escalation regimen (92.9%) tolerated continued HCQ treatment. One patient re-experienced eruptions on day 10 day after starting HCQ.

CONCLUSIONS

Mild late reactions are common in HCQ-induced hypersensitivity. A simpler dose-escalation regimen enables safe and easier reintroduction of HCQ but should not be applied to patients with immediate reactions or moderate late reactions.

P629Voluntary exercise associated with myokine production ameliorates cardiac remodeling and inflammation in a myocardial infarction mouse model

Background

Left ventricular (LV) remodeling, through excessive inflammation, leads to heart failure. Exercise (Ex) training is associated with a risk reduction in heart failure through direct and indirect mechanisms by which Ex contributes an anti-inflammatory effect. During Ex, contracting muscle fibers release myokines, including interleukins (ILs), tumor necrosis factor α (TNF-α), follistatin-like protein 1 (FSTL-1), and fibroblast growth factor 21 (FGF-21), into the bloodstream. These myokines may have beneficial effects on other damaged organs, such as an infarcted myocardium, through anti-inflammatory effects. However, the exact mechanisms of the anti-inflammatory effects of voluntary Ex in myocardial infarction (MI) are poorly understood. Therefore, we investigated the effect of voluntary Ex on cardiac remodeling and inflammation, the relationship between cardiac remodeling and skeletal muscle (SKM) response, and circulating myokine levels in a mouse model of MI.

Methods

Twelve-week-old male C57BL/6J mice were used and divided into the following 4 groups: sham operation (Sham), MI, Sham+Ex, and MI+Ex. MI was induced by ligation of the left anterior descending coronary artery. Ex groups began voluntary wheel running for 4 weeks after the operation. An echocardiography was performed at baseline and 4 weeks after the operation. The mRNA levels in the LV infarcted area and SKM were measured with RT-PCR and western blot analysis. Plasma levels of myokines were also measured with immunoassays.

Results

Four weeks after MI induction, echocardiographic evaluation showed that the MI mice had a larger LV end-diastolic diameter (LVEDD) and end-systolic diameter (LVESD) than the Sham mice. The MI mice also showed higher mRNA levels of TNF-α, IL-1β, IL-6, and IL-10 in the LV tissue when compared to the Sham mice. These changes were significantly ameliorated in the MI+Ex mice. Interestingly, in the MI+Ex mice, mRNA levels of IL-6, IL-1β, FSTL-1, and FGF-21 in the SKM were significantly higher than in the MI mice, while there were no significant differences in TNF-α and IL-10 levels in all groups. Similarly, protein expression levels of peroxisome proliferator-activated receptor gamma coactivator 1-alpha, sirtuin-1, and mitochondrial transcriptional factor A of mitochondrial function markers in SKM were also significantly higher in the MI+Ex mice than in the MI mice. Furthermore, there were significant correlations between plasma levels of IL-1β, but not other myokines, and LVEDD, and LVESD. In addition, there was also a significant correlation between the SKM IL-1β level and LVESD in the Sham+Ex mice (all, P<0.05).

Conclusions

Amelioration of cardiac remodeling and inflammation by voluntary Ex is associated with increased myokines, especially IL-1β, in a MI mouse model. These results suggest that increased myokine levels, through voluntary exercise, may play an important role in the prevention of cardiac remodeling after MI.

P6209Relationship between skin autofluorescence levels and clinical outcomes in heart failure patients undergoing cardiac rehabilitation

Background

Advanced glycation end-products, indicated by skin autofluorescence (SAF) levels, could be prognostic predictors of all-cause and cardiovascular mortality in patients with diabetes mellitus (DM) and renal disease. However, the clinical usefulness of SAF levels in patients with heart failure (HF) who underwent cardiac rehabilitation (CR) remains unclear.

Purpose

The purpose of this study was to investigate the prognostic value of SAF levels in patients with HF who underwent CR.

Methods

This study enrolled 204 consecutive patients with HF who had undergone CR at our university hospital between November 2015 and October 2017. Clinical characteristics and anthropometric data were collected at the beginning of CR. SAF levels were noninvasively measured with an autofluorescence reader. The major adverse cardiovascular event (MACE) was a composite of all-cause mortality and unplanned hospitalization for HF. Follow-up data concerning primary endpoints were collected until November 2018.

Results

Patients' mean age was 68.1 years, and 61% were males. Patients were divided into two groups according to the median SAF levels (high and low SAF groups). Patients in the high SAF group were significantly older, had a higher prevalence of chronic kidney disease, and histories of coronary artery bypass surgery; however, there were no significant between-group differences in sex, prevalence of DM, left ventricular ejection fraction, and physical function. During a median follow-up period of 623 days, 25 patients experienced all-cause mortality and 34 were hospitalized for HF. Kaplan–Meier analysis showed that patients in the high SAF group had a higher incidence of MACE (log-rank P<0.05), whereas when patients were divided into two groups according to the median hemoglobin A1c level, no significant between-group difference was observed for the incidence of MACE (Figure). After adjusting for confounding factors, Cox regression multivariate analysis revealed that SAF levels were independently associated with the incidence of MACE (hazard ratio: 1.74, 95% confidence interval: 1.12–2.65, P<0.05).

Figure 1

Conclusion

SAF levels were significantly associated with the incidence of MACE in patients with HF and may be useful for risk stratification in patients with HF who undergo CR.

P4141Lack of IkBNS promotes cholate-containing high-fat diet-induced inflammation and atherogenesis in low-density lipoprotein (LDL) receptor-deficient mice

Background

IκBNS is one of the nuclear IκB proteins and regulates a subset of Toll-like receptor (TLR) dependent genes. LPS acts as extremely strong stimulator of innate immunity. We tried to investigate whether stimulation of innate immunity could promote atherosclerosis in the IκBNS-deficient atherogenic mice. However all IκBNS-deficient mice died of LPS challenge at a dose of which almost all wild-type mice survived, because IκBNS-deficient mice are highly sensitive to LPS-induced endotoxin shock. Then, we decided to use a cholate-containing high fat diet (HFD(CA(+))), which has been widely used as an atherogenic diet in mice. Furthermore, HFD(CA(+)) has been shown to induce TLR4 mediated early inflammatory response. The present study aims to clarify the lack of IκBNS promotes atherogenesis in LDL receptor-deficient (LDLr−/−) mice fed HFD(CA(+)) compared with those fed a cholate-free HFD (HFD(CA(−)).

Methods and results

Mice that lacked IκBNS (IκBNS−/−) were crossed with LDLr−/− mice and formation of atherosclerotic lesions was analyzed after 6 weeks consumption of HFD(CA(+)) or HFD(CA(−)). The extent of atherosclerosis in the aorta (en face) was significantly increased in IκBNS−/−/LDLr−/−(CA(+)) mice compared with others after 6-week consumption of HFD (p<0.01) (Figure). Interestingly, HFD(CA(−)) did not induce significant atherosclerotic lesions in IκBNS−/−/LDLr−/− compared with LDLr−/− mice after 6-week consumption (Figure). Immunostaining of aortic root lesion revealed that HFD(CA(+)) significantly increased positive area of Mac-3 (macrophage) by 1.5-fold (p=0.01) and TLR4, interleukin-6 (IL-6) expression by 1.7-fold (P<0.05) and 1.5-fold (p<0.05) respectively in IκBNS−/−/LDLr−/− (CA(+)) compared to LDLr−/− (CA(+)) mice. Furthermore, active STAT3 (pSTAT3)-positive cells were significantly increased by 1.7-fold in the atherosclerotic lesions of IκBNS−/−/LDLr−/− (CA(+)) compared with LDLr−/− (CA(+)) mice (p<0.01). TLR4 positive areas, IL-6 positive areas, and pSTAT3 positive cells were overlapped with Mac-3, indicating that TLR4-IL-6-STAT3 axis was activated in macrophages in IκBNS−/−/LDLr−/− (CA(+)) mice. On the other hand, HFD(CA(−)) could not induce any difference in these immunoreactivities of arteriosclerotic lesions between IκBNS−/−/LDLr−/− (CA(−)) compared with LDLr−/− (CA(−)) mice. These findings suggest that IκBNS deficiency and HFD(CA(+)) promote atherogenesis in LDLr−/− mice via TLR4/IL-6/STAT3 pathway. Finally, we show the monocytes from peripheral blood of IκBNS−/−/LDLr−/− (CA(+)) mice were found to contain the most mounts of Ly6Chi among four groups, suggesting that lack of IκBNS enhances inflammation in the response HFD(CA(+)) feeding and thereby influence atherogenesis in IκBNS−/−/LDLr−/− mice.

Aortic root atherosclerotic lesions

Conclusions

The present study is the first to demonstrate that the activation of innate immune system using HFD(CA(+)) induced significant inflammation and atherogenesis in IκBNS−/−/LDLr−/− compared with LDLr−/− mice.

Seasonal and annual changes in PAH concentrations in a remote site in the Pacific Ocean

This paper reports the long term observation of particle-associated polycyclic aromatic hydrocarbons (PAHs) at Cape Hedo Atmosphere and Aerosol Monitoring Station, a remote site in the Western Pacific Ocean, from 2008 to 2015. This is the first long-term study that evaluated the contribution of long-range transport of PAHs in East Asia. No obvious trend (P > 0.05) was found in a particular season over the years. However, there are seasonal variations of PAH concentrations with higher in spring and winter. The higher PAH are attributed to air masses from the area including part of China. Source apportionment using three different approaches, i.e., PAH compositional pattern analysis, PAH diagnostic ratio analysis and positive matrix factorization modeling, showed the combined high contribution of biomass burning (18%, 14%) and coal combustion (33%, 24%) in spring and winter. In addition, the contribution of ship emissions (35%) was relatively high in spring, whereas that of vehicle emissions (36%) was relatively high in winter. The contribution of coal combustion to PAH has decreased throughout the years, likely due to changes in energy structure in China. The contribution of biomass burning to PAH has showed no trend, being stable, and that of vehicular emissions has increased.

Investigation of multi-mode spin-phonon coupling and local B-site disorder in Pr2CoFeO6 by Raman spectroscopy and correlation with its electronic structure by XPS and XAS studies

Electronic structure of Pr₂CoFeO₆ (at 300 K) was investigated by x-ray photoemission spectroscopy (XPS) and x-ray absorption spectroscopy techniques. All three cations, i.e. Pr, Co and Fe were found to be trivalent in nature. XPS valance band analysis suggested the system to be insulating in nature. The analysis suggested that Co³⁺ ions exist in low spin state in the system. Moreover, Raman spectroscopy study indicated the random distribution of the B-site ions (Co/Fe) triggered by same charge states. In temperature-dependent Raman study, the relative heights of the two observed phonon modes exhibited anomalous behaviour near magnetic transition temperature T _N ~ 270 K, thus indicating towards interplay between spin and phonon degrees of freedom in the system. Furthermore, clear anomalous softening was observed below T _N which confirmed the existence of strong spin-phonon coupling occurring for at least two phonon modes of the system. The line width analysis of the phonon modes essentially ruled out the role of magnetostriction effect in the observed phonon anomaly. The investigation of the lattice parameter variation across T _N (obtained from the temperature-dependent neutron diffraction measurements) further confirmed the existence of the spin-phonon coupling.

S-1 and irinotecan plus bevacizumab versus mFOLFOX6 or CapeOX plus bevacizumab as first-line treatment in patients with metastatic colorectal cancer (TRICOLORE): a randomized, open-label, phase III, noninferiority trial

Background

Combination therapy with oral fluoropyrimidine and irinotecan has not yet been established as first-line treatment of metastatic colorectal cancer (mCRC). We carried out a randomized, open-label, phase III trial to determine whether S-1 and irinotecan plus bevacizumab is noninferior to mFOLFOX6 or CapeOX plus bevacizumab in terms of progression-free survival (PFS).

Patients and methods

Patients from 53 institutions who had previously untreated mCRC were randomly assigned (1 : 1) to receive either mFOLFOX6 or CapeOX plus bevacizumab (control group) or S-1 and irinotecan plus bevacizumab (experimental group; a 3-week regimen: intravenous infusions of irinotecan 150 mg/m2 and bevacizumab 7.5 mg/kg on day 1, oral S-1 80 mg/m2 twice daily for 2 weeks, followed by a 1-week rest; or a 4-week regimen: irinotecan 100 mg/m2 and bevacizumab 5 mg/kg on days 1 and 15, S-1 80 mg/m2 twice daily for 2 weeks, followed by a 2-week rest). The primary end point was PFS. The noninferiority margin was 1.25; noninferiority would be established if the upper limit of the 95% confidence interval (CI) for the hazard ratio (HR) of the control group versus the experimental group was less than this margin.

Result

Between June 2012 and September 2014, 487 patients underwent randomization. Two hundred and forty-three patients assigned to the control group and 241 assigned to the experimental group were included in the primary analysis. Median PFS was 10.8 months (95% CI 9.6-11.6) in the control group and 14.0 months (95% CI 12.4-15.5) in the experimental group (HR 0.84, 95% CI 0.70-1.02; P < 0.0001 for noninferiority, P = 0.0815 for superiority). One hundred and fifty-seven patients (64.9%) in the control group and 140 (58.6%) in the experimental group had adverse events of grade 3 or higher.

Conclusion

S-1 and irinotecan plus bevacizumab is noninferior to mFOLFOX6 or CapeOX plus bevacizumab with respect to PFS as first-line treatment of mCRC and could be a new standard treatment.

Clinical trials number

UMIN000007834.

Feasibility of resecting the portal vein only when necessary during pancreatoduodenectomy for pancreatic cancer

Background

Whether the portal/superior mesenteric vein (PV) should be resected during pancreatoduodenectomy for pancreatic ductal adenocarcinoma (PDAC) based on preoperative CT or intraoperative findings is controversial.

Methods

This was a retrospective study with data of patients who had undergone pancreatoduodenectomy for PDAC between 2002 and 2016 in a tertiary referral centre. Based on the extent of contact between the PV and tumour on CT, patients were categorized into: group 1, no contact; group 2, contact 180° or less; group 3, contact greater than 180°. Extent of pathological PV invasion (pPV) (no invasion, pv0; invasion to tunica adventitia, pv1; invasion to media, pv2; invasion to intima, pv3) was compared with patient survival. To assess the feasibility of performing PV resection (PVR) based on intraoperative findings, the prognosis of patients in groups 1 and 2 with pv0 and no PVR (PVR(−)pv0) was compared with that of patients who had PVR (PVR(+)pv0), selected using propensity score matching.

Results

Groups 1, 2 and 3 comprised 230, 232 and 38 patients respectively, and PVR was performed in 10·9, 73·3 and 95 per cent of them (P < 0·001). Extent of pPV differed significantly (P < 0·001). The positive predictive value of radiological tumour contact with PV in predicting positive pPV was 42·6 per cent. In 64 patients with PVR(−)pv0 and 64 matched patients with PVR(+)pv0, the R0 resection rate (66 versus 73 per cent respectively; P = 0·337) and survival (median 32·4 versus 32·1 months; P = 0·780) were not significantly different.

Conclusion

PVR is needed only when the tumour is in clear contact with the PV and cannot be detached during surgery.

Acquired undescended testis and possibly associated testicular torsion in children with cerebral palsy or neuromuscular disease

INTRODUCTION

Torsion of an undescended testis (UDT) associated with cerebral palsy (CP) and neuromuscular disease (NMD) is an uncommon condition that is not well recognized by primary care physicians or healthcare providers.

OBJECTIVE

The objective of this study was to highlight the clinical importance of torsion of a UDT in children with CP and NMD.

MATERIALS AND METHODS

Eleven children with testicular torsion of a UDT operated on at the study institute between 1991 and 2015 were identified. The records of seven children (63.6%) associated with CP or NMD were retrospectively reviewed. Clinical findings of testicular torsion were assessed along with the treatment outcome and testicular salvageability.

RESULTS

All seven children were not identified with a UDT by public health checkup for infant and young children. No children with CP or NMD had torsion of a descended testis during the present study period. Median age at surgery was 15 years (range, 1-20 years). The testis location was at the external inguinal ring in five patients, in the inguinal canal in one, and in the superficial inguinal pouch in one. Of the contralateral testes, four were a UDT, one was a retractile testis, and two were descended testes. Orchiectomy was performed in six patients (85.7%). In the remaining patients, the testis was preserved but became atrophic.

DISCUSSION

This study demonstrated that children with CP or NMD may be affected with torsion of a UDT with peak at around puberty with the poor salvage rate, even if the testes appear descended in infancy and young children. Shortcomings of this study were the retrospective design and a small series of children undergoing surgery for torsion of a UDT.

CONCLUSION

Pediatric urologists need to educate primary care physicians and healthcare providers in the recognition of acquired UDTs and possibly associated testicular torsion in children with CP and NMD. Genital examination should be continued regularly until adolescence in these children to detect acquired UDT. These children should be referred to pediatric urologists to promote surgery as soon as the diagnosis of acquired UDT is carried out. It is believed that it is perhaps the best approach to prevent loss of the testis in children with CP and NMD.