Sequentially addressable dielectrophoretic array for high-throughput sorting of large-volume biological compartments

Droplet microfluidics has become a powerful tool in precision medicine, green biotechnology, and cell therapy for single-cell analysis and selection by virtue of its ability to effectively confine cells. However, there remains a fundamental trade-off between droplet volume and sorting throughput, limiting the advantages of droplet microfluidics to small droplets (<10 pl) that are incompatible with long-term maintenance and growth of most cells. We present a sequentially addressable dielectrophoretic array (SADA) sorter to overcome this problem. The SADA sorter uses an on-chip array of electrodes activated and deactivated in a sequence synchronized to the speed and position of a passing target droplet to deliver an accumulated dielectrophoretic force and gently pull it in the direction of sorting in a high-speed flow. We use it to demonstrate large-droplet sorting with ~20-fold higher throughputs than conventional techniques and apply it to long-term single-cell analysis of Saccharomyces cerevisiae based on their growth rate.

Search for Electron Antineutrino Appearance in a Long-Baseline Muon Antineutrino Beam

Electron antineutrino appearance is measured by the T2K experiment in an accelerator-produced antineutrino beam, using additional neutrino beam operation to constrain parameters of the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix. T2K observes 15 candidate electron antineutrino events with a background expectation of 9.3 events. Including information from the kinematic distribution of observed events, the hypothesis of no electron antineutrino appearance is disfavored with a significance of 2.40σ and no discrepancy between data and PMNS predictions is found. A complementary analysis that introduces an additional free parameter which allows non-PMNS values of electron neutrino and antineutrino appearance also finds no discrepancy between data and PMNS predictions.

Search for an Invisibly Decaying Z^{'} Boson at Belle II in e^{+}e^{-}→μ^{+}μ^{-}(e^{±}μ^{∓}) Plus Missing Energy Final States

Theories beyond the standard model often predict the existence of an additional neutral boson, the Z^{'}. Using data collected by the Belle II experiment during 2018 at the SuperKEKB collider, we perform the first searches for the invisible decay of a Z^{'} in the process e^{+}e^{-}→μ^{+}μ^{-}Z^{'} and of a lepton-flavor-violating Z^{'} in e^{+}e^{-}→e^{±}μ^{∓}Z^{'}. We do not find any excess of events and set 90% credibility level upper limits on the cross sections of these processes. We translate the former, in the framework of an L_{μ}-L_{τ} theory, into upper limits on the Z^{'} coupling constant at the level of 5×10^{-2}-1 for M_{Z^{'}}≤6  GeV/c^{2}.

Anti-enolase１antibodies from a patient with systemic lupus erythematosus accompanied by pulmonary arterial hypertension promote migration of pulmonary artery smooth muscle cells

OBJECTIVE

Pulmonary arterial hypertension (PAH) is an intractable complication in connective tissue diseases, but the pathological mechanisms responsible for progression remain obscure. This study aims to test whether patient IgG possesses biological activity promoting the migration of pulmonary artery smooth muscle cells (PASMCs).

METHODS

Cell migration was estimated by lamellipodia formation and by utilizing a Boyden chamber method. The specificity of autoantibodies was established by western blotting, ELISA, and immunocytochemistry. The target antigen was investigated by mass spectrometry.

RESULTS

IgG obtained from a patient with systemic lupus erythematosus (SLE) accompanied by PAH was found to promote lamellipodia formation and migration of PASMCs. The IgG bound to a ∼50 kDa protein expressed on the cell membrane, and in the cytoplasm and nucleus. This molecule was identified as enolase 1. Removal of enolase 1-binding antibodies from the IgG fraction, or treatment of the cells with an enolase inhibitor, significantly suppressed the migration of PASMCs.

CONCLUSION

Patients with SLE may possess autoantibodies to enolase 1 which stimulate the migration of PASMCs and are likely to play a role in the progression of PAH.

Development of Simple, Objective Chair-Standing Assessment of Physical Function in Older Individuals Using a KinectTM Sensor

BACKGROUND

With increasing interest in addressing quality of life of older individuals, tests such as the Functional Independence Measure (FIM) are widely used measures of infirmity and burden of care. However, these scales are largely qualitative and especially problematic when assessing movement-based tasks. While effective, reliable analysis of human movement is technically complicated and expensive; an infrared depth sensor is potentially a low-cost, portable devise which may provide a quantitative aspect to clinical testing.

OBJECTIVE

to assess the utility of the KinectTM sensor in providing an objective evaluation of human movement using an oft measured ADL (chair stand).

DESIGN

Cross-sectional study.

SETTING

Community, geriatric day-care center in Japan.

PARTICIPANTS

Men (n=136) and women (n=266) between 50 and 93 years of age, consisting of healthy (HE; n=312) and physically frail (FR; n= 90) individuals.

MEASUREMENTS

Subjects completed two trials of the chair stand, conducted without assistance. Trials were timed and recorded with KinectTM v2. Coronal plane angle (CPA) was determined by a line transecting the shoulder-center and waist relative to the vertical axis and was used to assess quality of the chair stand movement pattern.

RESULTS

Age, height, and body mass were not different between groups. CPA was significantly greater in FR (29.3 ± 8.3°) than HE (19.5 ± 6.5°). CPA and age were significantly related (r=0.148, p<0.01). An optimal threshold for CPA identifying frailty was determined by a receiver-operator characteristic curve with a CPA of 23.1° providing the greatest combination of sensitivity (79%) and specificity (73%).

CONCLUSION

During the chair stand, frail older adults adopted a forward lean position (increased CPA) compared to healthy older adults. This compensatory posture appears to facilitate torso rotation while reducing lower-limb muscular effort during standing. As such, CPA serves as an indicator of reduced lower-body function in older, frail adults.

P2634Prognostic value of admission left ventricular outflow tract velocity time integral in hospitalized heart failure patients with preserved ejection fraction: a report from the JASPER registry

Background

There are little effective treatment strategies for heart failure with preserved ejection fraction (HFpEF) to achieve a reduction of morbidity and mortality. Thus, accurate prognostication of patients with HFpEF could help improve their outcomes by identifying high-risk patients who might potentially benefit from intensive inpatient and outpatient monitoring and early referral for advanced HFpEF therapy. The left ventricular outflow tract velocity time integral (LVOT-VTI) is a representative non-invasive parameter for evaluating stroke volume, which can be a determinant of adverse outcomes in hospitalized patients with heart failure. However, the prognostic implication of admission LVOT-VTI for hospitalized HFpEF patients is undetermined.

Purpose

The aim of the present study was to investigate whether admission LVOT-VTI could predict poor clinical outcomes in hospitalized patients with HFpEF.

Methods

We examined consecutive 535 hospitalized HFpEF patients (left ventricular ejection fraction ≥50%) due to acute decompensated heart failure from the JASPER (JApanese heart failure Syndrome with Preserved Ejection fRaction) multicenter registry, obtained between November 2012 and March 2015. Patients without accessible LVOT-VTI data on admission were excluded. Finally, 214 patients were examined. The primary outcome of interest was composite of all-cause death and rehospitalization due to heart failure.

Results

Mean age was 78±11 years, 100 were male, and median plasma brain-type natriuretic peptide level was 400 (interquartile range [IQR] 223–711) pg/ml. During a median follow-up period of 688 (IQR 162–810) days, adverse events occurred in 83 patients (39%), including 47 (22%) all-cause death, 51 (24%) rehospitalization due to heart failure. The c-index of LVOT-VTI for predicting the composite of adverse events was 0.59 (95% CI 0.51 to 0.67), and the optimal cut-off value of LVOT-VTI was 15.8 cm. Low LVOT-VTI (≤15.8 cm) was significantly associated with higher adverse events compared to high LVOT-VTI (>15.8 cm) (Figure). Multivariable Cox regression analysis revealed that lower LVOT-VTI was an independent determinant of adverse events (HR 0.94, 95% CI 0.91 to 0.98, P=0.005) even after adjustment for pre-specified confounders including age, sex, systolic blood pressure, serum sodium, albumin, plasma brain-type natriuretic peptide and renal function.

Figure 1

Conclusions

Lower admission LVOT-VTI was an independent determinant of worse clinical outcomes in hospitalized HFpEF patients, indicating that LVOT-VTI on admission could be a useful marker for risk stratification in these patients.

P3468Tentative criteria of a combined RV3+SV3 voltage for early diagnosis of pediatric patients with hypertrophic cardiomyopathy

Background

A high voltage in midprecordial leads, termed the Katz-Wachtel sign, is a surrogate marker of left- or bi-ventricular hypertrophy. Asymmetrical interventricular hypertrophy is a characteristic feature of hypertrophic cardiomyopathy (HCM). In Japan, a school-based electrocardiographic (ECG) screening program was developed for all 1st, 7th, and 10th graders. Our hypothesis is that a combined voltage of RV3+SV3 {V3(R+S)} is a marker to screen pediatric HCM.

Purpose

[1] To develop V3(R+S) voltage criteria in 1st, 7th, and 10th graders at the screening program and [2] to determine whether the criteria are useful for the early diagnosis of HCM.

Methods

[1] Overall, 48,401 digitally stored ECGs from 16,773 1st graders (6-year-olds), 18,126 7th graders (12-year-olds), and 13,502 10th graders (15-year-olds) were obtained after excluding ECGs of subjects with underlying diseases, arrhythmias, and ST/T changes. The prevalence of HCM in children is estimated at 2.9 per 100,000 (1/34,000). The screening points were assumed to be between 1/2,000 and 1/5,000 to exclude the possibility of false negatives. [2] In 12 HCM patients (males/females=10/2) who were diagnosed after 12 years of age (one case was diagnosed at 9 years of age), the ECGs at the screening program of their first grade (at 6 years of age) were retrospectively examined.

Results

[1] The V3(R+S) criteria were 6.0 mV, 6.0 mV, and 5.5 mV for 1st, 7th, and 10th grader males, and 5.0 mV, 4.5 mV, and 4.0 mV for 1st, 7th, and 10th grade females, respectively. The number of subjects (and prevalence in parentheses) selected by the criteria were 2 (1/4175), 3 (1/2981), and 1 (1/6477) for 1st, 7th, and 10th grade males, and 2 (1/4212), 3 (1/3061), and 1 (1/3513) for 1st, 7th, and 10th grade females, respectively. [2] Four of 12 cases fulfilled the criteria. Of these, one suddenly died at 18 years of age, one experienced out-of-hospital cardiac arrest at 16 years of age, and one already had an interventricular thickness of 19 mm at 12 years of age.

Conclusions

These tentative V3(R+S) voltage criteria may be useful for the early diagnosis of pediatric HCM patients, particularly severe patients. The children and adolescents who were screened can be followed at 2–3-year intervals with ECGs and echocardiography. Early diagnosis and intervention including lifestyle modification and medication may prevent them expiring from out-of-hospital cardiac arrest or sudden death. Finally, the criteria should be validated in clinical settings.

Acknowledgement/Funding

A Health and Labour Sciences Grant from the Ministry of Health, Labour and Welfare of Japan (H27-019)

4089Prognostic value of cardiac metabolic activity assessed by 18F-FDG PET in patients with cardiac sarcoidosis

Background

Sarcoidosis is a systemic granulomatous disease that affects multiple organs. Among these,the presenceof cardiac involvementis recognized as a determinant of worse clinical outcomes. 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is a valuable modality for detecting active inflammatory lesions associated with cardiac sarcoidosis (CS). Generally,the maximum standardized uptake value (SUV) is suitable for evaluating disease activity in CS, but this quantitative method had limitations because it does not integrate both volume and intensity of FDG uptake simultaneously. Cardiac metabolic activity (CMA), which is quantitative measures of FDG volume-intensity, could be a diagnostic tool in the evaluation of CS. However, its prognostic implication in patients with CS is unclear.

Purpose

We sought to investigate whether CMA assessed by FDG-PET was associated with long-term worse clinical outcomes in patients with CS.

Methods

A total of 76 consecutive patients suspected CS who underwent FDG-PET between January 2010 and April 2018 in our university hospital were registered. We excluded patients whodid not meet the Japanese Ministry of Health and Welfare 2007 criteria (n=9) and those who received oral corticosteroids at the time of FDG-PET (n=5). Ultimately, 62 CS patients with definitively diagnosed were included in this study.We used a dedicated software to analyze SUV. Cardiac metabolic volume (CMV) was defined as the volume within the boundary determined by the threshold (SUV mean of blood pool × 1.5). CMA was calculated by multiplying CMV by SUV mean. The primary outcome of interest was the composite of advanced atrioventricular block, ventricular tachycardia, ventricular fibrillation, heart failure hospitalization, and all-cause death.

Results

During a median follow-up period of 1287 (IQR 806–1809) days after the first FDG-PET, the adverse events occurred in 12 patients (19%). Events group had significantly higher CMA compared to no events group (83 [IQR 11–330] vs. 354 [IQR 70–577]) (Figure A). Based on ROC analysis, the optimal cut-off value of CMA for the discrimination of the adverse events was 244 ml, and c-index was 0.71 (95% CI, 0.55–0.87). Patients with high CMA (≥244 ml, n=23) had lower LVEF, and higher prevalence of New York Heart Association functional class III or IV, and higher plasma BNP level compared to those with low CMA (<244 ml, n=39). Kaplan-Meier analysis revealed that composite adverse events more frequently occurred in patients with high CMA compared to those with low CMA (Figure B).Univariable Cox regression analysis showed that higher CMA was associated with increased subsequent risk of adverse events (HR 1.47, 95% CI 1.06–2.24).

Conclusions

Higher CMA assessed by FDG-PET was associated with worse clinical long-term outcomes in patients with CS, suggesting that measurement of the volume-intensity of abnormal FDG uptake may be useful for risk stratification in patients with CS.

P6173Plaque characteristics on coronary CT angiography in case of discordance between fractional flow reserve (FFR) and instantaneous wave-free ratio (IFR)

Background

The usefulness of fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) evaluation has been confirmed in the determination of revascularization of coronary artery disease. When FFR≤0.8 and iFR≤0.89 were regarded as the criteria for positivity, the discordance was noted in approximately 20%, but this cause has not been well established.

Purpose

The purpose of this study was to investigate the patient background and features on coronary CT angiography (CCTA) showing the discordance between FFR≤0.8 and iFR≤0.89.

Methods

The subjects were consecutive 85 cases with 108 vessels in which stenosis of 30–90% was detected at one vessel of at least 2mm or more in the major epicardial vessels and FFR and iFR was performed within subsequent 90 days, among suspected cases of coronary arterial diseases which underwent CCTA. The factors showing the discordance between FFR and iFR (patient background, coronary artery calcification score, high risk plaque features on CCTA (positive remodeling, low attenuation plaque), plaque characteristics by a plaque analysis software using a new algorithm called labeling method (vessel volume, plaque volume, lumen volume, plaque length, maximum plaque burden, necrotic core area, fibrous area and calcium area) were evaluated using logistic regression analysis on per-patient and per-vessel basis.

Results

There were no significant both FFR and iFR positive definite factors on per-patient basis. The lumen volume/vessel volume (OR: 0.93, 95% CI: 0.88–0.98, P=0.0032) (OR: 0.90, 95% CI: 0.85–0.95, P<0.0001),minimum lumen area (MLA) (OR: 0.59, 95% CI: 0.41–0.85, P=0.0006) (OR: 0.64, 95% CI: 0.44–0.92, P=0.0047), the plaque volume/vessel volume (OR: 1.05, 95% CI: 1.01–1.10, P=0.0114) (OR: 1.09, 95% CI: 1.04–1.15, P=0.0002) and maximum plaque burden (OR: 1.08, 95% CI: 1.01–1.15, P=0.0095) (OR: 1.06, 95% CI: 1.00–1.13, P=0.0406) were significant both FFR and iFR positive definite factors on per-vessels basis. Discordance between FFR≤0.8 and iFR≤0.89 was observed in 23 vessels (21.3%) of 19 patients. In FFR positive and iFR negative group (15 vessels, 13.9%), positive remodeling (PR) (OR: 4.38, 95% CI: 1.13–17.00, P=0.0294) was only significant predictor. In FFR negative and iFR positive group, there was no significant predictors.

Conclusions

In both FFR and iFR, only lumen volume /vessel volume, MLA, plaque volume/vessel volume and plaque burden were significant positive definite factors. As for the discordance between FFR and iFR, PR is significant predictor in FFR positive and iFR negative group.

P1806Diagnosis of isolated cardiac sarcoidosis using FDG-PET/CT on the basis of new guidelines

Introduction

Sarcoidosis is a systemic inflammatory disease which can involve any organs. The reported prevalence of isolated cardiac sarcoidosis (CS) varies widely because of the lack of an agreed definition of isolated CS (iCS). ICS was newly defined in the new guidelines for CS by Japanese Circulation Society.

Purpose

We aimed to examine the diagnostic accuracy of 18F-FDG PET/CT and the ratio of iCS in the whole CS by reviewing the patients with suspected CS undergoing the whole-body and cardiac FDG PET/CT scans.

Methods

We retrospectively reviewed 74 consecutive patients undergoing 18F-FDG PET/CT from 2013 to 2018 (mean age 60±14 years, 37 male) without the initiation of corticosteroid. Myocardial FDG uptake in CS was defined as a “focal” or “focal on diffuse” pattern. Systemic sarcoidosis (sCS) and iCS were diagnosed according to guidelines for the diagnosis and treatment of CS by Japanese Circulation Society. In short, iCS was diagnosed clinically when no clinical findings of sarcoidosis in any other organs and FDG uptake in heart were shown in addition to the following three of four criteria: high-grade atrioventricular block or fatal ventricular arrhythmia, structural abnormality, left ventricular contractile dysfunction, and delayed Gadolinium enhancement of myocardium on MRI.

Results

Of 31 patients with extra-cardiac sarcoidosis, 10 already met the diagnostic criteria of sCS before undergoing 18F-FDG PET/CT and 11 was newly diagnosed as sCS after FDG PET/CT. Of the remaining 43 without extra-cardiac sarcoidosis, 18 had FDG uptake in heart. Of 18 with FDG uptake in heart, iCS was diagnosed in 7, and sCS in 3 with extra-cardiac uptake of FDG as well as myocardium. Finally, 24 and 7 patients met the criteria of sCS and iCS based on the guideline, respectively. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of FDG PET/CT for CS including sCS and iCS were 90, 87, 88, 85, and 92%, respectively.

Conclusion

The ratio of iCS on the basis of new guidelines for diagnosis and treatment of CS was 22% of the whole CS.

Sustained Neurotrophin Release from Protein Nanoparticles Mediated by Matrix Metalloproteinases Induces the Alignment and Differentiation of Nerve Cells

The spatial and temporal availability of cytokines, and the microenvironments this creates, is critical to tissue development and homeostasis. Creating concentration gradients in vitro using soluble proteins is challenging as they do not provide a self-sustainable source. To mimic the sustained cytokine secretion seen in vivo from the extracellular matrix (ECM), we encapsulated a cargo protein into insect virus-derived proteins to form nanoparticle co-crystals and studied the release of this cargo protein mediated by matrix metalloproteinase-2 (MMP-2) and MMP-8. Specifically, when nerve growth factor (NGF), a neurotrophin, was encapsulated into nanoparticles, its release was promoted by MMPs secreted by a PC12 neuronal cell line. When these NGF nanoparticles were spotted onto a cover slip to create a uniform circular field, movement and alignment of PC12 cells via their extended axons along the periphery of the NGF nanoparticle field was observed. Neural cell differentiation was confirmed by the expression of specific markers of tau, neurofilament, and GAP-43. Connections between the extended axons and the growth cones were also observed, and expression of connexin 43 was consistent with the formation of gap junctions. Extensions and connection of very fine filopodia occurred between growth cones. Our studies indicate that crystalline protein nanoparticles can be utilized to generate a highly stable cytokine gradient microenvironment that regulates the alignment and differentiation of nerve cells. This technique greatly simplifies the creation of protein concentration gradients and may lead to therapies for neuronal injuries and disease.

Recurrent Aphthous Stomatitis Caused by Cytomegalovirus, Herpes Simplex Virus, and Candida Species in a Kidney Transplant Recipient: A Case Report

Recipients of organ transplants are immunosuppressed and at high risk of oral infection. Oral diseases are often neglected compared with infections of other organs that typically confer higher morbidity. However, severe local symptoms hinder oral intake, decrease quality of life, and are sometimes lethal. Here we describe a case of a 57-year-old woman who developed recurrent aphthous stomatitis after kidney transplantation; the cause of the infection was complex and included cytomegalovirus, herpes simplex virus, and Candida species. Since misdiagnosis of oral diseases impairs patient quality of life and increases morbidity, clinicians should be aware of possible etiologies of oral infections in renal transplant recipients.

Observation of Ξ(1620)^{0} and Evidence for Ξ(1690)^{0} in Ξ_{c}^{+}→Ξ^{-}π^{+}π^{+} Decays

We report the first observation of the double strange baryon Ξ(1620)^{0} in its decay to Ξ^{-}π^{+} via Ξ_{c}^{+}→Ξ^{-}π^{+}π^{+} decays based on a 980  fb^{-1} data sample collected with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. The mass and width are measured to be 1610.4±6.0(stat)_{-4.2}^{+6.1} (syst)  MeV/c^{2} and 59.9±4.8(stat)_{-7.1}^{+2.8}(syst)  MeV, respectively. We obtain 4.0σ evidence of the Ξ(1690)^{0} with the same data sample. These results shed light on the structure of hyperon resonances with strangeness S=-2.

CHEK1 coordinates DNA damage signaling and meiotic progression in the male germline of mice

The continuity of life depends on mechanisms in the germline that ensure the integrity of the genome. The DNA damage response/checkpoint kinases ATM and ATR are essential signaling factors in the germline. However, it remains unknown how a downstream transducer, Checkpoint Kinase 1 (CHEK1 or CHK1), mediates signaling in the male germline. Here, we show that CHEK1 has distinct functions in both the mitotic and meiotic phases of the male germline in mice. In the mitotic phase, CHEK1 is required for the resumption of prospermatogonia proliferation after birth and the maintenance of spermatogonia. In the meiotic phase, we uncovered two functions for CHEK1: one is the stage-specific attenuation of DNA damage signaling on autosomes, and the other is coordination of meiotic stage progression. On autosomes, the loss of CHEK1 delays the removal of DNA damage signaling that manifests as phosphorylation of histone variant H2AX at serine 139 (γH2AX). Importantly, CHEK1 does not have a direct function in meiotic sex chromosome inactivation (MSCI), an essential event in male meiosis, in which ATR is a key regulator. Thus, the functions of ATR and CHEK1 are uncoupled in MSCI, in contrast to their roles in DNA damage signaling in somatic cells. Our study reveals stage-specific functions for CHEK1 that ensure the integrity of the male germline.

Dietary factors associated with the development of physical frailty in community-dwelling older adults

OBJECTIVES

Nutrition plays an important role in the development of frailty, and the present study examined the association between energy, macronutrient, and food intake and the development of physical frailty.

DESIGN

Prospective cohort study.

SETTING

The National Institute for Longevity Sciences - Longitudinal Study of Aging (NILS-LSA), a community-based study.

PARTICIPANTS

Participants included 166 men and 117 women aged 65-86 years without frailty components at baseline who participated in both the sixth (2008-2010) and seventh (2010-2012) waves of the NILS-LSA.

MEASUREMENTS

Physical frailty was assessed using the modified criteria established by the Cardiovascular Health Study (2001). All participants were classified as "robust (number of frailty components: 0)," "prefrail (1-2)," or "frail (3-5)." Energy, macronutrient, and food intake was calculated based on 3-day dietary records during the sixth wave. Associations between dietary intake per day and the development of frailty 2 years later (from robust at the sixth wave to prefrail/frail at the seventh wave) were examined using multiple logistic regression analysis after adjusting for sex, baseline age, and other covariables.

RESULTS

Among the participants included, 36% were classified as prefrail/frail 2 years later. Higher energy [1 standard deviation (SD), odds ratio (95% confidence interval): 362 kcal, 0.68 (0.49-0.94)], protein [16 g, 0.72 (0.53-0.97)], and fat [15 g, 0.69 (0.52-0.92)] intake was negatively associated with frailty development. Higher meat [38 g, 0.68 (0.51-0.92)] and dairy [114 g, 0.73 (0.55-0.96)] intake was negatively associated with frailty development. Higher energy intake was negatively associated with the development of weakness (low grip strength) and low activity, while higher protein intake was negatively associated with the development of low activity.

CONCLUSION

Increased consumption of meat and dairy products may provide sufficient protein and fat necessary for achieving higher energy intake, thereby effectively preventing physical frailty among older Japanese individuals.

Search for CP Violation in Neutrino and Antineutrino Oscillations by the T2K Experiment with 2.2×10^{21} Protons on Target

The T2K experiment measures muon neutrino disappearance and electron neutrino appearance in accelerator-produced neutrino and antineutrino beams. With an exposure of 14.7(7.6)×10^{20} protons on target in the neutrino (antineutrino) mode, 89 ν_{e} candidates and seven anti-ν_{e} candidates are observed, while 67.5 and 9.0 are expected for δ_{CP}=0 and normal mass ordering. The obtained 2σ confidence interval for the CP-violating phase, δ_{CP}, does not include the CP-conserving cases (δ_{CP}=0, π). The best-fit values of other parameters are sin^{2}θ_{23}=0.526_{-0.036}^{+0.032} and Δm_{32}^{2}=2.463_{-0.070}^{+0.071}×10^{-3}  eV^{2}/c^{4}.

The P element invaded rapidly and caused hybrid dysgenesis in natural populations of Drosophila simulans in Japan

Transposable elements not only can change genomic positions and disperse across the gene pool, but also can jump to another species through horizontal transmission. Of late, the P element, a DNA transposon in insects, was shown to cross the genetic boundary from Drosophila melanogaster to D. simulans in Europe around 2006. To understand the dynamics of transposable elements, especially in the early stages of invasion, we examined 63 lines of D. simulans from 11 natural populations in Japan established in 1976-2015. Based on PCR analyses, P elements were demonstrated to exist in Japan in 2008 and later. One copy of the full-length P element was identified and mapped to a site on chromosome 3 L in a genome. All of 18 copies of P elements examined shared "A" at the nucleotide position 2040, which is representative of the direct descendants of the original P element that invaded in D. simulans. We also found that some lines having P elements can induce intensive gonadal dysgenesis in D. simulans at 29°C. Our present results imply that P elements in D. simulans arrived at the east end of Asia just a few years later than or almost simultaneously to the initial invasion in Europe, Africa, and North America, suggesting a more astonishingly rapid spread than previously assumed.

Prognostic nutritional index and early mortality with percutaneous endoscopic gastrostomy

BACKGROUND

Although percutaneous endoscopic gastrostomy (PEG) is a well-accepted and less invasive method of feeding tube placement in patients with swallowing difficulties, complications and early death after PEG have been reported.

AIM

This study aimed to evaluate predictive factors associated with 30-day mortality after PEG, and to assess the utility of nutritional supporting period before PEG in reducing early mortality following PEG.

DESIGN

An observational study.

METHODS

We retrospectively analyzed 268 patients who underwent PEG at Sapporo Shirakaba-dai Hospital from 2006 to 2010, using clinical and laboratory data to analyze predictive factors associated with early death after PEG. Then, we prospectively assessed 152 consecutive patients assessed for eligibility for PEG from 2011 to 2014. We assessed the patients' nutritional condition using Onodera's prognostic nutritional index (PNI), and supported nutrition for more than 10 days before PEG in patients with a poor nutritional index (PNI < 37).

RESULTS

In both univariate and multivariate analyses in the retrospective study, Onodera's PNI of less than 37 was the only predictive factor for early mortality. In the second study, among the 115 patients who finally underwent PEG, early mortality rates improved to 1.7% from 5.2% in the first study. Conversely, 32% of patients with malnutrition who did not undergo PEG died within 30 days.

CONCLUSION

Nutritional status might be a predictive factor for early mortality after PEG. In patients with poor nutritional status, nutritional supporting period before PEG might improve the outcomes and reduce unnecessary PEG.

Observation of an Excited Ω^{-} Baryon

Using data recorded with the Belle detector, we observe a new excited hyperon, an Ω^{*-} candidate decaying into Ξ^{0}K^{-} and Ξ^{-}K_{S}^{0} with a mass of 2012.4±0.7(stat)±0.6(syst)  MeV/c^{2} and a width of Γ=6.4_{-2.0}^{+2.5}(stat)±1.6(syst)  MeV. The Ω^{*-} is seen primarily in ϒ(1S),ϒ(2S), and ϒ(3S) decays.

Search for Boosted Dark Matter Interacting with Electrons in Super-Kamiokande

A search for boosted dark matter using 161.9 kt yr of Super-Kamiokande IV data is presented. We search for an excess of elastically scattered electrons above the atmospheric neutrino background, with a visible energy between 100 MeV and 1 TeV, pointing back to the Galactic center or the Sun. No such excess is observed. Limits on boosted dark matter event rates in multiple angular cones around the Galactic center and Sun are calculated. Limits are also calculated for a baseline model of boosted dark matter produced from cold dark matter annihilation or decay. This is the first experimental search for boosted dark matter from the Galactic center or the Sun interacting in a terrestrial detector.

Propensity score-matched comparison of non-anatomical resection and radiofrequency ablation for hepatocellular carcinoma in patients with up to three tumours, each measuring up to 3 cm in diameter

Background

Non‐anatomical liver resection (NAR) and radiofrequency ablation (RFA) are treatment options for early‐stage hepatocellular carcinoma (HCC). The aim was to compare the outcomes of NAR and RFA for HCC in patients with three or fewer tumour nodules, each measuring not more than 3 cm in maximum diameter.

Methods

Eligible patients undergoing NAR or RFA with curative intent between September 2002 and December 2014 were identified. A propensity score‐matching analysis was performed to reduce bias, and outcomes in these patients were analysed.

Results

From a total of 199 patients, 1:1 propensity score matching identified 70 matched pairs. Patients having NAR had a longer hospital stay (median 10 days versus 4 days for those who had RFA; P < 0·001) and a higher morbidity rate (24 versus 10 per cent respectively; P = 0·042). Patients who had NAR had slightly better recurrence‐free survival but this failed to reach statistical significance in univariable analysis (P = 0·064). There was no significant difference in overall survival between the two groups (P = 0·475). RFA was identified as an independent risk factor for recurrence‐free survival (hazard ratio (HR) 1·57; P = 0·041) in multivariable analysis. Local recurrence was significantly more common in patients receiving RFA (23 versus 1 per cent; P < 0·001).

Conclusion

RFA was an independent risk factor for shorter recurrence‐free survival, with a significantly higher local recurrence rate than NAR. Despite these differences, overall survival was not affected.

Search for the Exotic Meson X(5568) with the Collider Detector at Fermilab

A search for the exotic meson X(5568) decaying into the B_{s}^{0}π^{±} final state is performed using data corresponding to 9.6  fb^{-1} from pp[over ¯] collisions at sqrt[s]=1960  GeV recorded by the Collider Detector at Fermilab. No evidence for this state is found and an upper limit of 6.7% at the 95% confidence level is set on the fraction of B_{s}^{0} produced through the X(5568)→B_{s}^{0}π^{±} process.

Differential Cross Section and Photon-Beam Asymmetry for the γ[over →]p → π^{-}Δ^{++}(1232) Reaction at Forward π^{-} Angles for E_{γ}=1.5-2.95 GeV

Differential cross sections and photon-beam asymmetries for the γ[over →]p→π^{-}Δ^{++}(1232) reaction have been measured for 0.7<cosθ_{π}^{c.m.}<1 and E_{γ}=1.5-2.95  GeV at SPring-8/LEPS. The first-ever high statistics cross-section data are obtained in this kinematical region, and the asymmetry data for 1.5<E_{γ}(GeV)<2.8 are obtained for the first time. This reaction has a unique feature for studying the production mechanisms of a pure uu[over ¯] quark pair in the final state from the proton. Although there is no distinct peak structure in the cross sections, a non-negligible excess over the theoretical predictions is observed at E_{γ}=1.5-1.8  GeV. The asymmetries are found to be negative in most of the present kinematical regions, suggesting the dominance of π exchange in the t channel. The negative asymmetries at forward meson production angles are different from the asymmetries previously measured for the photoproduction reactions producing a dd[over ¯] or an ss[over ¯] quark pair in the final state. Advanced theoretical models introducing nucleon resonances and additional unnatural-parity exchanges are needed to reproduce the present data.

Modification of LSC spectra of 125I by high atomic number elements

The ¹²⁵I pulse-height spectra via a liquid scintillation counter (LSC) displayed notable variations. The counting efficiencies of higher and lower energy peaks increased and decreased, respectively, with the enhancement of the amount of high atomic numbered elements within the cocktails. This tendency was ascribed to the increasing probability of the interaction of photons with the scintillation cocktail. Moreover, it was noted that the shape of a ¹²⁵I spectrum strongly depends on the amount of high atomic numbered elements.

Reappraisal of classification of distal cholangiocarcinoma based on tumour depth

Background

In the eighth edition of the AJCC cancer staging classification, the T system for distal cholangiocarcinoma (DCC) has been revised from a layer-based to a depth-based approach. The aim of this study was to propose an optimal T classification using a measured depth in resectable DCC.

Methods

Patients who underwent pancreatoduodenectomy for DCC at 32 hospitals between 2001 and 2010 were included. The distance between the level of the naive bile duct and the deepest cancer cells was measured as depth of invasion (DOI). Invasive cancer foci were measured as invasive tumour thickness (ITT). Log rank χ2 scores were used to determine the cut-off points, and concordance index (C-index) to assess the survival discrimination of each T system.

Results

Among 404 patients, DOI was measurable in 182 (45·0 per cent) and ITT was measurable in all patients, with median values of 2·3 and 5·6 mm respectively. ITT showed a positive correlation with DOI (rs = 0·854, P &lt; 0·001), and the cut-off points for prognosis were 1, 5 and 10 mm. Median survival time was shorter with increased ITT: 12·4 years for ITT below 1 mm, 5·2 years for ITT at least 1 mm but less than 5 mm, 3·0 years for ITT at least 5 mm but less than 10 mm, and 1·5 years for ITT 10 mm or more (P &lt; 0·001). This classification exhibited more favourable prognostic discrimination than the T systems of the seventh and eighth editions of the AJCC (C-index 0·646, 0·622 and 0·624 respectively).

Conclusion

ITT is an accurate approach for depth assessment in DCC. The four-tier ITT classification with cut-off points of 1, 5 and 10 mm seems to be a better T system than those in the seventh and eighth editions of the AJCC classification.

Retinoic acid signalling is a candidate regulator of the expression of pituitary-specific transcription factor Prop1 in the developing rodent pituitary

Development of the anterior pituitary proceeds via spatiotemporal patterning of transcription factors and signalling molecules. Among them, retinoic acid (RA) functions as an important signalling molecule for vertebrate organogenesis in many tissues. However, little is known regarding the target genes in the developing pituitary. The present study aimed to clarify the relationship between endogenous RA signalling and mRNA expression of the pituitary-specific transcription factor Prop1 in the pituitary primordium of Rathke's pouch. Gene expression analysis and in situ hybridisation demonstrated that retinaldehyde dehydrogenases (Raldhs) and all types of RA receptors (Rars) are expressed at the level of transcription in the rat Rathke's pouch. Ex vivo organ culture using Rathke's pouch and an in vitro reporter assay demonstrated that RA signalling increases the expression level of Prop1 via RARα. Moreover, a reporter assay using serial truncated constructs of the 5'-upstream region of mouse Prop1 revealed a predicted cis-regulatory element of RARα. This is the first report of a relationship between RA signalling and Prop1-expression during early pituitary development.

Frequencies of chromosomal inversions in Drosophila melanogaster in Fukushima after the nuclear power plant accident

In order to investigate genetic impact of a large amount of radionuclides released by the Fukushima Dai-ichi Nuclear Power Plant accident in 2011, we surveyed 2,304 haploid genomes of Drosophila melanogaster collected in three localities in Fukushima in 2012 and 2013 for chromosomal inversions. No unique inversion was found in 298 genomes in 2012 and only two in 2,006 genomes in 2013. The observed frequencies were even lower than the long-term average frequency of unique inversions in Japan. The common cosmopolitan inversions were also examined in Fukushima, Kyoto, and Iriomote (Okinawa) in 2012. Among three samples in Fukushima, the flies in Iizaka, where environmental radiation level was the highest, showed the lowest frequency of In(2L)t, but the highest frequency of In(3R)P, contrary to the expectation of decreasing of their frequencies in higher polluted areas. These results suggest that, at this level of genetic analysis, Fukushima populations of D. melanogaster would not have been negatively impacted following the release of radionuclides. Transposable P-element mobility was not likely to induce DNA damage solely or synergistically with radioactivity, because their transposition activity was totally repressed in the Fukushima strains. However, it should be noted that, because of limitations in access to the exclusion zone, we could only sample the populations in areas of relatively low radioactive contamination (0.39-0.63 μSv/h). Therefore, the present study is likely to be underpowered to detect any effects that might be expected in heavily contaminated areas.

Combined Forward-Backward Asymmetry Measurements in Top-Antitop Quark Production at the Tevatron

The CDF and D0 experiments at the Fermilab Tevatron have measured the asymmetry between yields of forward- and backward-produced top and antitop quarks based on their rapidity difference and the asymmetry between their decay leptons. These measurements use the full data sets collected in proton-antiproton collisions at a center-of-mass energy of sqrt[s]=1.96  TeV. We report the results of combinations of the inclusive asymmetries and their differential dependencies on relevant kinematic quantities. The combined inclusive asymmetry is A_{FB}^{tt[over ¯]}=0.128±0.025. The combined inclusive and differential asymmetries are consistent with recent standard model predictions.

Enhancement of Osteogenesis by Concanavalin a in Human Bone Marrow Mesenchymal Stem Cell Cultures

This study investigates concanavalin A (ConA) as a novel factor that may enhance osteogenesis of mesenchymal stem cells (MSCs) in vitro. Various factors, such as cytokine bone morphogenetic protein-2 (BMP-2), have been studied for their possible promotion of MSC osteogenesis in vivo and in vitro. However, the factor that might be safer, more effective, and less expensive than these has not been determined. We therefore cultured human MSCs in osteogenic medium in the presence or absence of ConA, and used calcium assays to compare the effects of ConA and BMP-2 on MSC calcification. We also used enzyme-linked immunosorbent assay (ELISA) and quantitative polymerase chain reaction (PCR) to evaluate the expression levels of bone-specific markers. ConA and BMP-2 enhanced calcification with comparable effectiveness. The combination of ConA and BMP-2 further enhanced calcification slightly but significantly. ConA also increased osteocalcin and BMP-2 protein levels in MSC culture medium. Furthermore, ConA increased osteocalcin, RUNX2, BMP-2, BMP-4, and BMP-6 mRNA expression levels. However, the gene expression pattern of ConA-stimulated MSCs was different from that of MSCs stimulated by BMP-2. Together, these results suggest that ConA and BMP-2 enhance MSC osteogenesis via different pathways. ConA-induced bone formation in MSC cultures may be useful in regenerative medicine or tissue engineering in clinical studies, as well as in basic research on bone formation.