Mass, Spectroscopy, and Two-Neutron Decay of ^{16}Be

The structure and decay of the most neutron-rich beryllium isotope, ^{16}Be, has been investigated following proton knockout from a high-energy ^{17}B beam. Two relatively narrow resonances were observed for the first time, with energies of 0.84(3) and 2.15(5) MeV above the two-neutron decay threshold and widths of 0.32(8) and 0.95(15) MeV, respectively. These were assigned to be the ground (J^{π}=0^{+}) and first excited (2^{+}) state, with E_{x}=1.31(6)  MeV. The mass excess of ^{16}Be was thus deduced to be 56.93(13) MeV, some 0.5 MeV more bound than the only previous measurement. Both states were observed to decay by direct two-neutron emission. Calculations incorporating the evolution of the wave function during the decay as a genuine three-body process reproduced the principal characteristics of the neutron-neutron energy spectra for both levels, indicating that the ground state exhibits a strong spatially compact dineutron component, while the 2^{+} level presents a far more diffuse neutron-neutron distribution.

Search for a Dark Photon and an Invisible Dark Higgs Boson in μ^{+}μ^{-} and Missing Energy Final States with the Belle II Experiment

The dark photon A^{'} and the dark Higgs boson h^{'} are hypothetical particles predicted in many dark sector models. We search for the simultaneous production of A^{'} and h^{'} in the dark Higgsstrahlung process e^{+}e^{-}→A^{'}h^{'} with A^{'}→μ^{+}μ^{-} and h^{'} invisible in electron-positron collisions at a center-of-mass energy of 10.58 GeV in data collected by the Belle II experiment in 2019. With an integrated luminosity of 8.34  fb^{-1}, we observe no evidence for signal. We obtain exclusion limits at 90% Bayesian credibility in the range of 1.7-5.0 fb on the cross section and in the range of 1.7×10^{-8}-200×10^{-8} on the effective coupling ϵ^{2}×α_{D} for the A^{'} mass in the range of 4.0  GeV/c^{2}<M_{A^{'}}<9.7  GeV/c^{2} and for the h^{'} mass M_{h^{'}}<M_{A^{'}}, where ϵ is the mixing strength between the standard model and the dark photon and α_{D} is the coupling of the dark photon to the dark Higgs boson. Our limits are the first in this mass range.

Precise Measurement of Differential Cross Sections of the Σ^{-}p→Λn Reaction in Momentum Range 470-650 MeV/c

The differential cross sections of the Σ^{-}p→Λn reaction were measured accurately for the Σ^{-} momentum (p_{Σ}) ranging from 470 to 650  MeV/c at the J-PARC Hadron Experimental Facility. Precise angular information about the Σ^{-}p→Λn reaction was obtained for the first time by detecting approximately 100 reaction events at each angular step of Δcosθ=0.1. The obtained differential cross sections show a slightly forward-peaking structure in the measured momentum regions. The cross sections integrated for -0.7≤cosθ≤1.0 were obtained as 22.5±0.68 [statistical error(stat.)] ±0.65 [systematic error(syst.)] mb and 15.8±0.83(stat)±0.52(syst)  mb for 470<p_{Σ}(MeV/c)<550 and 550<p_{Σ}(MeV/c)<650, respectively. These results show a drastic improvement compared with past measurements of the hyperon-proton scattering experiments. They will play essential roles in updating the theoretical models of the baryon-baryon interactions.

Recent progress and future prospects of hyperon nucleon scattering experiment

A new hyperon-proton scattering experiment, dubbed J-PARC E40, was performed to measure differential cross sections of the Σ+p, Σ−p elastic scatterings and the Σ−p → Λn scattering by identifying a lot of Σ particles in the momentum ranging from 0.4 to 0.8 GeV/c produced by the π±p → K+Σ± reactions. We successfully measured the differential cross sections of these three channels with a drastically improved accuracy with a fine angular step. These new data will become important experimental constraints to improve the theories of the two-body baryon-baryon interactions. Following this success, we proposed a new experiment to measure the differential cross sections and spin observables by using a highly polarized Λ beam for providing quantitative information on the ΛN interaction. The results of three Σp channels and future prospects of the Λp scattering experiment are described.

Precise Measurement of the D^{0} and D^{+} Lifetimes at Belle II

We report a measurement of the D^{0} and D^{+} lifetimes using D^{0}→K^{-}π^{+} and D^{+}→K^{-}π^{+}π^{+} decays reconstructed in e^{+}e^{-}→cc[over ¯] data recorded by the Belle II experiment at the SuperKEKB asymmetric-energy e^{+}e^{-} collider. The data, collected at center-of-mass energies at or near the ϒ(4S) resonance, correspond to an integrated luminosity of 72  fb^{-1}. The results, τ(D^{0})=410.5±1.1(stat)±0.8(syst)  fs and τ(D^{+})=1030.4±4.7(stat)±3.1(syst)  fs, are the most precise to date and are consistent with previous determinations.

Search for B^{+}→K^{+}νν[over ¯] Decays Using an Inclusive Tagging Method at Belle II

A search for the flavor-changing neutral-current decay B^{+}→K^{+}νν[over ¯] is performed at the Belle II experiment at the SuperKEKB asymmetric energy electron-positron collider. The data sample corresponds to an integrated luminosity of 63  fb^{-1} collected at the ϒ(4S) resonance and a sample of 9  fb^{-1} collected at an energy 60 MeV below the resonance. Because the measurable decay signature involves only a single charged kaon, a novel measurement approach is used that exploits not only the properties of the B^{+}→K^{+}νν[over ¯] decay, but also the inclusive properties of the other B meson in the ϒ(4S)→BB[over ¯] event, to suppress the background from other B meson decays and light-quark pair production. This inclusive tagging approach offers a higher signal efficiency compared to previous searches. No significant signal is observed. An upper limit on the branching fraction of B^{+}→K^{+}νν[over ¯] of 4.1×10^{-5} is set at the 90% confidence level.

Quasifree Neutron Knockout Reaction Reveals a Small s-Orbital Component in the Borromean Nucleus ^{17}B

A kinematically complete quasifree (p,pn) experiment in inverse kinematics was performed to study the structure of the Borromean nucleus ^{17}B, which had long been considered to have a neutron halo. By analyzing the momentum distributions and exclusive cross sections, we obtained the spectroscopic factors for 1s_{1/2} and 0d_{5/2} orbitals, and a surprisingly small percentage of 9(2)% was determined for 1s_{1/2}. Our finding of such a small 1s_{1/2} component and the halo features reported in prior experiments can be explained by the deformed relativistic Hartree-Bogoliubov theory in continuum, revealing a definite but not dominant neutron halo in ^{17}B. The present work gives the smallest s- or p-orbital component among known nuclei exhibiting halo features and implies that the dominant occupation of s or p orbitals is not a prerequisite for the occurrence of a neutron halo.

Surface Localization of the Dineutron in ^{11}Li

The formation of a dineutron in the ^{11}Li nucleus is found to be localized to the surface region. The experiment measured the intrinsic momentum of the struck neutron in ^{11}Li via the (p,pn) knockout reaction at 246  MeV/nucleon. The correlation angle between the two neutrons is, for the first time, measured as a function of the intrinsic neutron momentum. A comparison with reaction calculations reveals the localization of the dineutron at r∼3.6  fm. The results also support the density dependence of dineutron formation as deduced from Hartree-Fock-Bogoliubov calculations for nuclear matter.

Correlation between respiratory muscle weakness and frailty status as risk markers for prognosis in patients with cardiovascular disease

Background

Respiratory muscle weakness (RMW), frequently observed in patients with cardiovascular disease (CVD), is documented as a predictor for exercise intolerance and poor prognosis. On the other hand, frailty is commonly associated with disease condition, leading to increased risk of morbidity and mortality. Although the developmental mechanism of RMW and frailty is partly similar, the relationship between these statuses remains unclear.

Purpose

We aimed to investigate the correlation between RMW and frailty and its impact on prognosis in patients with CVD.

Methods

We studied 771 consecutive patients (68.5±13.1 years, 256 females) who were hospitalized for CVD treatment and underwent cardiac rehabilitation during hospitalization. Patients who received thoracic surgery within the last 3 months or could not perform respiratory function test were excluded from this study. As patient characteristics, we obtained body mass index, comorbidity conditions, smoking history, blood examinations, echocardiographical variables, and lung function from medical database. The frailty status on admission was assessed using frailty score consisting of 5 items including gait speed, nutrition/shrinking, physical activity, forgetfulness, and emotions/exhaustion, and patients who had 3 items were defined as frailty. We also measured maximal inspiratory pressure (PImax) as respiratory muscle strength at hospital discharge, and RMW was defined with PImax &lt;70% of predicted value. Primary end-point was all-cause clinical events including all-cause death and/or unplanned readmission after hospital discharge. We examined the prevalence of RMW and frailty and the correlation between these statuses. The relationships of RMW with the clinical events for each presence or absence of frailty were also investigated using multivariate Cox proportional hazard models.

Results

RMW and frailty were defined in 163 (33.5%) and 126 (28.7%) patients, respectively, and 95 patients (12.4%) among them showed an overlap of both statuses (Figure 1). Frailty was detected as a significant indicator of RMW after adjusting for confounding factors (adjusted odds ratio: 1.57, 95% CI: 1.12–2.19, P=0.009). Over the median follow-up periods of 1.2 years, all-cause clinical events occurred in 154 patients (20.0%). RMW was significantly and independently associated with increased incidence of all-cause clinical events in patients with both non-frailty (adjusted hazard ratio [HR]: 1.64, 95% CI: 1.09–2.46, P=0.017) and frailty (adjusted HR: 1.97, 95% CI: 1.14–3.42, P=0.015) even after adjusting for clinical confounding factors (Figure 2).

Conclusions

This study is the first to demonstrate that RMW correlated to frailty in patients with CVD, and 12.4% of patients had overlap status. Moreover, RMW was significantly associated with an increased risk of all-cause clinical events in patients with CVD and frailty.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Japan Society for the Promotion of Science Grant-in-Aid

Search for Axionlike Particles Produced in e^{+}e^{-} Collisions at Belle II

We present a search for the direct production of a light pseudoscalar a decaying into two photons with the Belle II detector at the SuperKEKB collider. We search for the process e^{+}e^{-}→γa, a→γγ in the mass range 0.2<m_{a}<9.7  GeV/c^{2} using data corresponding to an integrated luminosity of (445±3)  pb^{-1}. Light pseudoscalars interacting predominantly with standard model gauge bosons (so-called axionlike particles or ALPs) are frequently postulated in extensions of the standard model. We find no evidence for ALPs and set 95% confidence level upper limits on the coupling strength g_{aγγ} of ALPs to photons at the level of 10^{-3}  GeV^{-1}. The limits are the most restrictive to date for 0.2<m_{a}<1  GeV/c^{2}.

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}.

P2610Increase in comfortable walking speed during hospitalization predicts the readmission due to decompensated heart failure in heart failure patients with preserved ejection fraction

Background

Heart failure patients with preserved ejection fraction (HFpEF) have reduced exercise capacity and poor prognosis as well as those with reduced ejection fraction (HFrEF). Both cardiac function and exercise capacity have been known as prognostic factors for patients with HFrEF. However, few reports documented the relations of comfortable walking speed (CWS) during hospitalization to exercise capacity and prognosis. is used as a clinical measure to assess their exercise capacity and prognosis. However, few reports documented the correlations of CWS with exercise capacity and prognosis in patients with HFpEF.

Purpose

This study aimed to investigate whether CWS at hospital discharge and the increase in CWS during hospitalization predicted the readmission due to decompensated heart failure in patients with HFpEF and HFrEF.

Methods

Patients who were hospitalized due to heart failure with New York Heart Association (NYHA) Functional Classification III or IV were prospectively followed up for 3 years after hospital discharge. Consequently, 264 patients, 173 males and 92 females, aged 73.2±6.8 years were studied. Patients were divided into 3 groups based on their ejection fraction (EF): HFpEF group (EF≥50%; n=98), HFrEF group (EF<40%; n=138) and heart failure with mid-range ejection fraction (HFmrEF) group (40%≤EF≤49%; n=28). We assessed clinical characteristics including age, gender, height, NYHA functional classification, etiology of CHF, plasma brain natriuretic peptide and left ventricular ejection fraction (LVEF) on admission, and measured CWS several days after admission and at discharge. We determined significant factors affecting the readmission and their cut-off values using univariate and multivariate logistic regression analyses and the area under the receiver operating characteristics curves in the three groups.

Results

Forty patients (40.8%), 54 (39.1%) and 6 (21.4%) were readmitted in the HFpEF, HFrEF and HFmrEF groups, respectively, within 3 years after the discharge. Univariate logistic regression analysis detected the age, LVEF, CWS at discharge and the CWS increase during hospitalization as significant limiting factors for readmission in the HFpEF and HFrEF groups (P<0.05, respectively). The multivariate logistic regression analysis detected the CWS increase during hospitalization as significant limiting factor for readmission in the HFpEF and HFrEF groups (P<0.001 and P<0.05, respectively). The odds ratios of readmission were 1.86 (P<0.01) and 1.44 (P<0.001) with each 5-meter decrease of CWS increase during hospitalization and predictive cut-off values of the CWS increase were 7.5 and 8.5 meters/min in the HFpEF and HFrEF groups, respectively.

Conclusion

This study demonstrated that the CWS increase during hospitalization was a strong predictor for readmission due to decompensated heart failure in patients not only with HFrEF but also with HFpEF and each predictive the cut-off value was 7.5 and 8.5 meters/min.

298Change in respiratory muscle strength predicts clinical events in patients with chronic heart failure

Background

Respiratory muscle weakness, frequently observed in patients with chronic heart failure (CHF), has been documented as a predictor for poor prognosis. Several studies have reported that respiratory muscle training increases respiratory muscle strength and consequently improves exercise tolerance and quality of life in these patients. However, the relationship between the change in respiratory muscle strength and prognosis is still unclear.

Purpose

We aimed to investigate whether the change in respiratory muscle strength following cardiac rehabilitation predicts the incidence of clinical events in CHF patients.

Methods

We studied 348 patients with CHF who were hospitalized because of decompensated heart failure and received 5-month cardiac rehabilitation during hospitalization and after hospital discharge. Clinical characteristics including aetiology of heart failure, comorbidity conditions, medications, blood examination and echocardiographic variables were obtained from clinical records. We also measured maximal inspiratory pressure (PImax) as respiratory muscle strength at hospital discharge and 5 months later. The change of PImax (ΔPImax) between the 5-month observation period was examined. We followed up the patients after the observation period and investigated the incidence of all-cause mortality or all-cause unplanned readmission. In statistical analysis, patients were divided into two groups based on the median value of ΔPImax. We compared the event-free survival rate between the two groups using the Kaplan-Meier method with a log-rank test. We also performed the Cox proportional hazard model to clarify whether the ΔPImax was an independent predictor for the incidence of clinical events.

Results

Over a median follow-up of 1.6 years, 121 patients (34.8%) died or readmitted, and their rate of incidence was 21.7/100 person-years. The higher ΔPImax was associated significantly with a higher rate of event-free survival (Log-rank: 8.085, P=0.004, Figure 1). In univariate Cox proportional hazard model, ΔPImax was a significant predictor for the all-cause mortality/readmission (unadjusted hazard ratio for PImax increase of 10 cmH2O: 0.842, 95% CI: 0.763 - 0.931, P=0.001). Even after adjustment for clinical confounding factors including baseline PImax, ΔPImax remained significant and independent predictor for the all-cause mortality/readmission (adjusted hazard ratio for PImax increase of 10 cmH2O: 0.862, 95% CI: 0.763 - 0.974, P=0.017, Figure 2).

Conclusion

This study is the first to demonstrate that the change in respiratory muscle strength following cardiac rehabilitation independently predicts the incidence of clinical events in patients with CHF. The increase in PImax of 10 cmH2O was associated significantly with a 14% decrease in the rate of all-cause mortality or readmission.

Acknowledgement/Funding

JSPS KAKENHI JP16K16442

P3106Atrial fibrillation is not associated with the responses to exercise training in heart failure patients with preserved ejection fraction

Background

Atrial fibrillation (AF) is known as a common arrhythmia in heart failure patients with preserved left ventricular ejection fraction (HFpEF). Several studies have reported that HFpEF patients with AF show lower exercise tolerance and poorer prognosis as compared with those with sinus rhythm (SR). On the other hand, exercise training is documented to improve peripheral muscle function and exercise tolerance in HFpEF patients. However, the relationship between AF status and outcomes due to exercise training is still unclear in these patients.

Purpose

We aimed to investigate the influence of AF on the responses to outcomes with exercise training in HFpEF patients.

Methods

We studied 426 patients with HFpEF who received 5-month cardiac rehabilitation including exercise training during hospitalization and after hospital discharge. As clinical characteristics, we obtained body mass index, disease aetiology, comorbidity conditions, blood examination and echocardiographic variables from medical records. We also measured isometric quadriceps strength (QS) and 6-minute walk distance (6MWD) as peripheral muscle strength and exercise tolerance, respectively. The QS and 6MWD were assessed at hospital discharge as the baseline and 5 months later. AF status was determined by the presence on electrocardiogram at baseline 6MWD or medical history of AF during hospitalization. In statistical analysis, we compared baseline clinical characteristics, QS and 6MWD between the rhythm status (SR group or AF group). We also examined the changes in QS and 6MWD from baseline to the 5-month observation period (ΔQS and Δ6MWD) and compared them between the 2 groups using analysis of covariance with adjustment for baseline clinical confounding factors.

Results

At baseline, 289 patients (68%) were in SR, and 111 patients (26%) had AF. The AF was associated significantly with older age (P<0.001) and lower levels of estimated glomerular filtration rate (P=0.013), QS (P<0.001) and 6MWD (P<0.001) at baseline. The QS increased significantly from 25.2±11.0 kg at baseline to 30.8±13.0 kg after 5-month cardiac rehabilitation in the SR group, and from 21.1±8.3 kg to 26.0±9.4 kg in the AF group (P<0.001, respectively). The 6MWD also increased significantly from 394.8±129.2 to 463.5±133.5 meters in the SR, and from 343.7±107.9 to 403.0±114.5 meters in the AF (P<0.001, respectively). There were no significant differences in ΔQS and Δ6MWD between the SR and AF groups even after adjustment for clinical confounding factors including baseline QS or 6MWD (Figure).

Conclusions

The AF status in HFpEF patients was associated with older age, lower peripheral muscle function and also lower exercise tolerance at baseline, but not associated with the responses to exercise training.

Acknowledgement/Funding

JSPS KAKENHI JP16K16442

Long-term survival of a patient with recurrent gallbladder carcinoma, treated with chemotherapy, immunotherapy, and surgery: a case report

Background

Gallbladder cancer (GBC) is one of the refractory diseases. Multidisciplinary approach including immunotherapy for such cancers has received much attention in recent years.

Case presentation

A 59-year-old man underwent an extended cholecystectomy for GBC (pathological stage II, T2 N0 M0, [per UICC 7th edition]) that was incidentally found during cholelithiasis surgery, and was then treated with adjuvant gemcitabine (GEM). Three months later, when a recurrence-suspected lesion was detected in segment 5 (S5) of his liver, we started adoptive immunotherapies with cytokine-activated killer (CAK) cell infusions, combined with chemotherapy. After a year of adjuvant immunochemotherapy, the S5 lesion disappeared on imaging, but lesions suspected metastatic recurrence again appeared in S7 and S8 at 4 years and 6 months post-surgery, for which GEM and cisplatin (CDDP) were administered as second-line chemotherapy. Immunochemotherapy produced stable disease (per RECIST) for 9 months, when tumor growth was detected; open microwave coagulo-necrotic therapy (MCN) was performed for these lesions. Three years after MCN, a solitary liver metastasis was detected in S4. MCN was conducted again, and peritoneal dissemination was found intraoperatively. A month after the second MCN, the patient’s carcinoembryonic antigen (CEA) level had increased. Therefore, GEM and tegafur-gimeracil-oteracil potassium (TS-1) were administered as third-line chemotherapy. We also switched the adoptive immunotherapy for tumor-associated antigen-pulsed dendritic cell-activated killer (DAK) cell immunotherapy. After nine courses of GEM and TS-1 administration, CEA had decreased to a normal level. At the time of reporting, 9 years and 6 months have passed since the initial surgery, and 18 months have passed since the peritoneal metastasis was detected. GEM and CDDP are currently administered as fourth-line chemotherapy because of re-increased CEA. Although an undeniable metastasis was found in his para-aortic lymph node, this patient visits our clinic regularly for immunotherapy.

Conclusion

We here report a rare case of long-term survival of recurrent GBC well controlled by multidisciplinary therapy. Immunotherapy may be a promising modality among multidisciplinary methods for advanced cancer.

Biliary complications in 108 consecutive recipients with duct-to-duct biliary reconstruction in living-donor liver transplantation

BACKGROUND

Biliary complications remain the leading cause of postoperative complications after living-donor liver transplantation (LDLT) in patients undergoing duct-to-duct choledochocholedochostomy. The aim of this study was to analyze the causes of these complications.

METHODS

One hundred eight patients who underwent LDLT with duct-to-duct biliary reconstruction at Mie University Hospital were enrolled in this study. The mean follow-up time was 58.4 months (range, 3-132). The most recent 18 donors underwent indocyanine green (ICG) fluorescence cholangiography for donor hepatectomy. The development of biliary complications was retrospectively analyzed. Biliary complications were defined as needing endoscopic or radiologic treatment.

RESULTS

Biliary leakages and strictures occurred in 6 (5.6%) and 15 (13.9%) of the recipients, respectively, and 3 donors (2.7%) experienced biliary leakage. However, since the introduction of ICG fluorescence cholangiography, we have not encountered any biliary complications in either donors or recipients. Biliary leakage was an independent risk factor for the development of biliary stricture (P = .013). Twelve (80%) of the 15 recipients with biliary stricture had successful nonoperative endoscopic or radiologic management, and 3 patients underwent surgical repair with hepaticojejunosotomy.

CONCLUSIONS

Biliary leakage was an independent factor for biliary stricture. ICG fluorescence cholangiography might be helpful to reduce biliary complications after LDLT in both donors and recipients.

Hypertension and hepatitis C virus infection are strong risk factors for developing late renal dysfunction after living donor liver transplantation: significance of renal biopsy

BACKGROUND

Late renal dysfunction (LRD) after liver transplantation develops due to several factors such as viral hepatitis, calcineurin inhibitor, diabetes mellitus, and hypertension. The aim of our study was to clarify the risk factors for LRD after living donor liver plantation (LDLT) by using simple criteria for LRD and paying special attention to the significance of renal biopsy.

PATIENTS AND METHODS

Among the 98 recipients undergoing LDLT between March 2002 and June 2008, there were 77 patients who survived more than 1 year and had been followed at our clinic. LRD was simply defined as a postoperative serum creatinine level of 1.5/L or more at any point in time after 1 year from undergoing LDLT. The perioperative risk factors for developing LRD after LDLT were analyzed by uni- and multivariate analyses, and regardless of serum creatinine level, a renal biopsy was indicated when the patient developed clinical symptoms.

RESULTS

Comparing the risk factors between 22 patients with LRD and 55 without LRD, univariate analysis revealed recipient's age, generation, hypertension, hepatitis C virus (HCV) antibody-positive, pretransplantation serum creatinine level, and graft-to-recipient weight ratio to be significant risk factors. By multivariate analysis, HCV and hypertension were selected as independent risk factors. Renal biopsy was indicated in the 4 patients with proteinuria, all of whom were positive for HCV. However, by histologic and/or electron micrographic analyses, only 1 patient was diagnosed with HCV-related membranous proliferative nephritis, 1 with diabetic nephropathy, and 2 with drug (tacrolimus) -induced renal dysfunction.

CONCLUSION

Although HCV and hypertension were determined to be independent risk factors for LRD after LDLT, a renal biopsy should be performed when clinical symptoms develop regardless of creatinine levels to provide appropriate treatment.

Imaging molecular adsorption and desorption dynamics on graphene using terahertz emission spectroscopy

Being an atomically thin material, graphene is known to be extremely susceptible to its environment, including defects and phonons in the substrate on which it is placed as well as gas molecules that surround it. Thus, any device design using graphene has to take into consideration all surrounding components, and device performance needs to be evaluated in terms of environmental influence. However, no methods have been established to date to readily measure the density and distribution of external perturbations in a quantitative and non-destructive manner. Here, we present a rapid and non-contact method for visualizing the distribution of molecular adsorbates on graphene semi-quantitatively using terahertz time-domain spectroscopy and imaging. We found that the waveform of terahertz bursts emitted from graphene-coated InP sensitively changes with the type of atmospheric gas, laser irradiation time, and ultraviolet light illumination. The terahertz waveform change is explained through band structure modifications in the InP surface depletion layer due to the presence of localized electric dipoles induced by adsorbed oxygen. These results demonstrate that terahertz emission serves as a local probe for monitoring adsorption and desorption processes on graphene films and devices, suggesting a novel two-dimensional sensor for detecting local chemical reactions.

ESR of Cation Radicals of Methyl-substituted Benzenes in a CF3CCl3 Matrix

A new matrix, 1,1,1-trifluorotrichloroethane, CF3CCl3, has been employed in radiation chemistry studies to stabilise positive ions. As a test, positive ions of benzene, toluene, orto-, meta- and paraxylene and biphenyl have been generated by y-irradiation of the solutes contained in the CF3CCl3 matrix at 77 K. The ions have been investigated by ESR, and hyperfine couplings have been obtained. The data complement and correct the splitting values obtained previously in the adsorbed state.

MUC4 and MUC1 expression in adenocarcinoma of the stomach correlates with vessel invasion and lymph node metastasis: an immunohistochemical study of early gastric cancer

We have previously reported that MUC4 expression is a poor prognostic factor in various carcinomas. Our previous study also showed that MUC1 expression in gastric cancers, including the early and advanced stages is a poor prognostic factor. In the present study, the expression profiles of MUC4 and MUC1 were examined by immunohistochemistry (IHC) using two anti-MUC4 monoclonal antibodies (MAbs), 8G7 and 1G8, and anti-MUC1 MAb DF3 in 104 gastrectomy specimens of early gastric adenocarcinoma with submucosal invasion (pT1b2), including 197 histological subtype lesions. Before the IHC study of the human specimens, we evaluated the specificity of the two MAbs by Western blotting and IHC of two MUC4 mRNA expressing gastric cancer cell lines. MAb 8G7 reacted clearly, whereas MAb 1G8 did not show any reactivity, in either Western blotting or IHC. In the IHC of the gastric cancers, the expression rates of MUC4/8G7 detected by MAb 8G7, MUC4/1G8 detected by MAb 1G8 and MUC1/DF3 detected by MAb DF3 in well differentiated types (70%, 38/54; 67%, 36/54; 52%, 28/54) were significantly higher than those in poorly differentiated types (18%, 10/55; 36%, 20/55; 13%, 7/55) (P<0.0001; P = 0.0021; P<0.0001), respectively. The MUC4/8G7 expression was related with lymphatic invasion (r = 0.304, P = 0.033). On the other hand, the MUC4/1G8 expression was related with lymphatic invasion (r = 0.395, P = 0.001) and lymph node metastasis (r = 0.296, P = 0.045). The MUC1/DF3 expression was related with lymphatic invasion (r = 0.357, P = 0.032) and venous invasion (r = 0.377, P = 0.024). In conclusion, the expression of MUC4 as well as MUC1 in early gastric cancers is a useful marker to predict poor prognostic factors related with vessel invasion.

Living donor liver transplantation for the patients with portal vein thrombosis: use of an interpositional venous graft passed posteriorly to the pancreatic parenchyma without using jump graft

BACKGROUND

It is difficult to reconstruct the portal vein (PV) using a long interpositional venous graft in living donor liver transplant (LDLT) patients with portal vein thrombosis (PVT), which involves the confluence of the superior mesenteric vein (SMV) and splenic vein (SV). We successfully performed LDLT for three patients with PVT using an interpositional vascular conduit passing posterior to the pancreas without a jump graft.

METHODS

Three of 130 patients who underwent LDLT in our hospital between March 2002 and June 2011 required this technique. After indentifying the location of the SMV, SV and gastrocolic trunk, we ligated and cut the posterior superior pancreaticoduodenal vein and other short branches from the PV. The PV was drawn inferiorly to the pancreas and transected at the confluence of SMV and SV. The external iliac vein or internal jugular vein was sacrificed as a graft for anastomosis to the cut end of the SMV using 6-0 polypropylene running sutures. Then the venous graft was drawn superiorly to the pancreas by passing it posterior to the pancreas parenchyma for anastomosis to the liver graft PV. The interpositional vein was placed posterior to the pancreas where the PV used to be.

RESULTS

All three patients displayed favorable postoperative courses with the Doppler ultrasound demonstrating good portal flow perioperatively. The postoperative portogram demonstrated patency of the vascular graft.

CONCLUSION

This method is easy and helpful to treat portal vein thrombosis, by providing the shortest route between the PV of the donor and the SMV of the recipient.

A novel anti-MUC1 antibody against the MUC1 cytoplasmic tail domain: use in sensitive identification of poorly differentiated cells in adenocarcinoma of the stomach

BACKGROUND

Isolated cancer cells of non-solid type poorly differentiated adenocarcinoma (por2) or signet-ring cell carcinoma (sig) are frequently seen in scirrhous gastric cancers with a very poor prognosis. These cells are often scattered in granulation tissue or desmoplastic fibrotic tissue and tend to be overlooked in routine pathological examination. We aimed to raise a novel antibody that can identify the isolated cancer cells easily.

METHODS

Because the MUC1 cytoplasmic tail domain (CTD) has many biological roles including tumor progression and cell adhesion disturbance and is expected to be expressed in isolated cancer cells, we raised a novel monoclonal antibody (MAb) MUC1-014E against an intracellular nonrepeating 19-amino-acid sequence (RYVPPSSTDRSPYEKVSAG: N-1217-1235-C) of the MUC1 CTD, using a synthetic peptide including the 7-amino-acid epitope (STDRSPY: N-1223-1229-C).

RESULTS

In the immunohistochemical staining of 107 gastrectomy specimens including 48 por2 and 31 sig lesions, the MAb MUC1-014E showed high rates of positive staining (≥5% of carcinoma cells stained) for por2 (100%) and sig (97%), and of the highest intensity staining (4+, ≥75% of carcinoma cells stained) for por2 (100%) and sig (90%). In the 89 biopsy specimens including 82 por2 and 38 sig lesions, the MAb MUC1-014E showed high rates of positive staining for por2 (100%) and sig (100%) and of 4+ staining for por2 (87%) and sig (84%). All the rates were significantly higher than those with cytokeratins (AE1/AE3 or CAM5.2).

CONCLUSIONS

The MAb MUC1-014E is very useful for accurate detection of isolated cancer cells in scirrhous gastric cancers.

Angiopoietin-like protein 2 sensitively responds to weight reduction induced by lifestyle intervention on overweight Japanese men

OBJECTIVE

Overexpression of Angiopoietin-like protein 2 (Angptl2) in obese adipose tissues promotes adipose tissue inflammation and its-related metabolic abnormalities. In a comparative study with adiponectin, we investigated whether alterations in serum Angptl2 concentrations reflect the effect of lifestyle intervention on weight loss and improved metabolic parameters in overweight subjects.

METHODS

A total of 154 Japanese men (age, 40.9±5.1 years; body mass index, 26.9±3.6 kg m(-2); abdominal circumference, 94.1±8.9 cm) underwent a 3-month lifestyle intervention and underwent follow-up for 3 months thereafter.

RESULTS

Decreased serum Angptl2 levels, but not increased serum adiponectin levels, were immediately apparent at the end of 3-month lifestyle intervention. Angptl2 levels continued to decrease for 3 months in parallel with body weight loss and improvement in metabolic indicators. In subjects showing 6% weight reduction, markedly reduced Angptl2 levels were detected at the end of 3-month intervention, whereas increased adiponectin levels were detected 3 months after the end of intervention. Multivariate analysis revealed changes in serum Angptl2 levels associated with changes in triglycerides (TGs), aspartate aminotransferase and alanine aminotransferase. In contrast, changes in serum adiponectin levels were associated with altered high-density lipoprotein cholesterol (HDL-C) and fasting plasma glucose levels.

CONCLUSION

A 3-month lifestyle intervention promoted weight reduction and improved glucose and lipid metabolism, an effect maintained 3 months later. Notably, our findings indicate that decreased Angptl2 levels are a good indicator of reduced visceral fat and metabolic improvement at early stages of lifestyle intervention. Thus, Angptl2 reflects adiposity and might be a key protein to regulate inflammation and TG metabolism, whereas adiponectin levels could reflect improved glucose and HDL-C metabolism.

Time trend in treatment-related deaths of patients with advanced non-small-cell lung cancer enrolled into phase III trials of systemic treatment

PURPOSE

Despite recent improvements in supportive care, treatment-related death (TRD) remains a serious problem for lung cancer patients undergoing systemic chemotherapy. However, few studies have formally assessed possible changes in the TRD rate over the past two decades.

PATIENTS AND METHODS

We searched phase III trials to address the role of systemic treatment of advanced non-small-cell lung cancer (NSCLC). Time trend was assessed using linear regression analysis.

RESULTS

The overall incidence of TRD was calculated from 119 trials including 263 chemotherapy arms (46 477 patients), with information about the causes of deaths available for 197 arms (75%, 30 147 patients). Cisplatin-based regimens were the most frequently investigated. The crude TRD rate in the overall cohort of 119 trials was 1.26% and has been notably consistent over the investigated time (P = 0.762). The most common cause of death was febrile neutropenia, with no significant change in its incidence over the years (P = 0.139). In contrast, deaths due to renal toxicity decreased significantly (P = 0.042), whereas deaths due to pulmonary disorder increased significantly (P = 0.007). Among the pharmacological agents investigated, docetaxel (Taxotere) and epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) were associated with relatively high rates of deaths from pulmonary disorders, but EGFR-TKIs were not associated with death from any other cause.

CONCLUSIONS

Despite of potential confounders in our results, the overall TRD rate has remained low, but not negligible, in phase III trials for advanced NSCLC, over the past two decades. Notably, the incidence and pattern of TRD stratified by cause have changed considerably.