Intravital Two-Photon Microscopy of the Transplanted Mouse Lung

Complications after lung transplantation are largely related to the host immune system responding to the graft. Such immune responses are regulated by crosstalk between donor and recipient cells. A better understanding of these processes relies on the use of preclinical animal models and is aided by an ability to study intra-graft immune cell trafficking in real-time. Intravital two-photon microscopy can be used to image tissues and organs for depths up to several hundred microns with minimal photodamage, which affords a great advantage over single-photon confocal microscopy. Selective use of transgenic mice with promoter-specific fluorescent protein expression and/or adoptive transfer of fluorescent dye-labeled cells during intravital two-photon microscopy allows for the dynamic study of single cells within their physiologic environment. Our group has developed a technique to stabilize mouse lungs, which has enabled us to image cellular dynamics in naïve lungs and orthotopically transplanted pulmonary grafts. This technique allows for detailed assessment of cellular behavior within the vasculature and in the interstitium, as well as for examination of interactions between various cell populations. This procedure can be readily learned and adapted to study immune mechanisms that regulate inflammatory and tolerogenic responses after lung transplantation. It can also be expanded to the study of other pathogenic pulmonary conditions.

Murine Left Pulmonary Hilar Clamp Model of Lung Ischemia Reperfusion Injury

Ischemia reperfusion injury (IRI) during lung transplantation is a major risk factor for post-transplant complications, including primary graft dysfunction, acute and chronic rejection, and mortality. Efforts to study the underpinnings of IRI led to the development of a reliable and reproducible mouse model of left lung hilar clamping. This model involves a surgical procedure performed in an anesthetized and intubated mouse. A left thoracotomy is performed, followed by careful lung mobilization and dissection of the left pulmonary hilum. The hilar clamp involves reversible suture ligation of the pulmonary hilum with a slipknot, which stops the arterial inflow, venous outflow, and airflow through the left mainstem bronchus. Reperfusion is initiated by careful removal of the suture. Our laboratory uses 30 min of ischemia and 1 h of reperfusion for the experimental model in the current investigations. However, these time periods can be modified depending on the specific experimental question. Immediately prior to sacrifice, arterial blood gas can be obtained from the left ventricle after a 4 min period of right hilar clamping to ensure that the PaO2 values obtained are attributed to the injured left lung alone. We also describe a method to measure cell extravasation with flow cytometry, which involves intravenous injection of a fluorochrome-labeled antibody specific for the cell(s) to be studied prior to sacrifice. The left lung can then be harvested for flow cytometry, frozen or fixed, paraffin-embedded immunohistochemistry, and quantitative polymerase chain reaction. This hilar clamp technique allows for detailed study of the cellular and molecular mechanisms underlying IRI. Representative results reveal decreased left lung oxygenation and histologic evidence of lung injury following hilar clamping. This technique can be readily learned and reproduced by personnel with and without microsurgical experience, leading to reliable and consistent results and serving as a widely adoptable model for studying lung IRI.

Eosinophils restrain humoral alloimmunity after lung transplantation

While the function of many leukocytes in transplant biology has been well defined, the role of eosinophils is controversial and remains poorly explored. Conflicting data exist regarding eosinophils' role in alloimmunity. Due to their prevalence in the lung, and their defined role in other pulmonary pathologies such as asthma, we set out to explore the role of eosinophils in the long-term maintenance of the lung allograft. We noted that depletion of eosinophils results in the generation of donor-specific antibodies. Eosinophil depletion increased memory B cell, plasma cell, and antibody-secreting cell differentiation and resulted in de novo generation of follicular germinal centers. Germinal center formation depended on the expansion of CD4+Foxp3-Bcl6+CXCR5+PD-1+ T follicular helper (Tfh) cells, which increase in number after eosinophil depletion. Mechanistically, we demonstrate that eosinophils prevent Tfh cell generation by acting as the dominant source of IFN-γ in an established lung allograft, thus facilitating Th1 rather than Tfh polarization of naive CD4+ T cells. Our data thus describe what we believe is a unique and previously unknown role for eosinophils in maintaining allograft tolerance and suggest that indiscriminate administration of eosinophil-lytic corticosteroids for treatment of acute cellular rejection may inadvertently promote humoral alloimmunity.

Smoking exposure-induced bronchus-associated lymphoid tissue in donor lungs does not prevent tolerance induction after transplantation

The presence of bronchus-associated lymphoid tissue (BALT) in donor lungs has been suggested to accelerate graft rejection after lung transplantation. Although chronic smoke exposure can induce BALT formation, the impact of donor cigarette use on alloimmune responses after lung transplantation is not well understood. Here, we show that smoking-induced BALT in mouse donor lungs contains Foxp3+ T cells and undergoes dynamic restructuring after transplantation, including recruitment of recipient-derived leukocytes to areas of pre-existing lymphoid follicles and replacement of graft-resident donor cells. Our findings from mouse and human lung transplant data support the notion that a donor's smoking history does not predispose to acute cellular rejection or prevent the establishment of allograft acceptance with comparable outcomes to nonsmoking donors. Thus, our work indicates that BALT in donor lungs is plastic in nature and may have important implications for modulating proinflammatory or tolerogenic immune responses following transplantation.

B cells mediate lung ischemia/reperfusion injury by recruiting classical monocytes via synergistic B cell receptor/TLR4 signaling

Ischemia/reperfusion injury-mediated (IRI-mediated) primary graft dysfunction (PGD) adversely affects both short- and long-term outcomes after lung transplantation, a procedure that remains the only treatment option for patients suffering from end-stage respiratory failure. While B cells are known to regulate adaptive immune responses, their role in lung IRI is not well understood. Here, we demonstrated by intravital imaging that B cells are rapidly recruited to injured lungs, where they extravasate into the parenchyma. Using hilar clamping and transplant models, we observed that lung-infiltrating B cells produce the monocyte chemokine CCL7 in a TLR4-TRIF-dependent fashion, a critical step contributing to classical monocyte (CM) recruitment and subsequent neutrophil extravasation, resulting in worse lung function. We found that synergistic BCR-TLR4 activation on B cells is required for the recruitment of CMs to the injured lung. Finally, we corroborated our findings in reperfused human lungs, in which we observed a correlation between B cell infiltration and CM recruitment after transplantation. This study describes a role for B cells as critical orchestrators of lung IRI. As B cells can be depleted with currently available agents, our study provides a rationale for clinical trials investigating B cell-targeting therapies.

Cross-Sectional and Longitudinal Associations of Creatinine-to-Cystatin C Ratio with Sarcopenia Parameters in Older Adults

OBJECTIVES

Accumulating evidence from cross-sectional studies suggests that the serum creatinine-to-cystatin C ratio (CCR) may be a useful biomarker for sarcopenia. This study aimed to assess the cross-sectional and longitudinal associations of CCR with sarcopenia and its parameters in community-dwelling older adults.

DESIGN

Cross-sectional and longitudinal study.

SETTING AND PARTICIPANTS

This 6-year prospective cohort study included the repeated measurement data from 1,253 Japanese residents (662 males and 591 females) aged ≥65 years who underwent medical checkups in Kusatsu and Hatoyama, Japan. A total of 4,421 observations were collected.

MEASUREMENTS

The CCR was grouped into quartiles by sex (Q1-Q4) using Q4 as the reference category. Sarcopenia was defined according to the Asian Working Group for Sarcopenia 2019 algorithm. Skeletal muscle mass index (SMI) measured using segmental multifrequency bioelectrical impedance analysis, handgrip strength (HGS), usual gait speed (UGS), and maximal gait speed (MGS) were measured repeatedly as sarcopenia parameters. The association of the CCR with changes in sarcopenia, SMI, HGS, UGS, and MGS during the 6-year period were analyzed using a generalized linear mixed-effects model.

RESULTS

The prevalence of sarcopenia at baseline was 13.1% (11.9% in males and 14.5% in females). In a cross-sectional analysis, the CCR quartile was inversely associated with sarcopenia and was positively associated with SMI, HGS, and MGS (P for trend < 0.001). In a longitudinal analysis during the 6 years, a significant increase in sarcopenia in Q2 (B = 1.1% point/year; P = 0.026 for group-by-time interaction) and significant declines in SMI (B = -0.01 kg/m2/year; P = 0.044 for group-by-time interaction) and MGS (B = -0.008 m/sec/year; P = 0.041 for group-by-time interaction) in Q1 were observed compared with Q4. However, the dose-response relationship was significant only for MGS (P = 0.033 for trend). No significant group-by-time interaction was observed for HGS. CCR was not significantly associated with UGS either cross-sectionally or longitudinally.

CONCLUSIONS

CCR is a useful biomarker regarding the status of sarcopenia. It may be used for sarcopenia screening even in older adults whose physical function is difficult to assess. However, further longitudinal studies are needed to determine whether CCR can be a predictor of future sarcopenia.

Specialized Proresolving Lipid Meditators Agonistic to Formyl Peptide Receptor Type 2 Attenuate Ischemia-reperfusion Injury in Rat Lung

BACKGROUND

Lung ischemia-reperfusion injury (IRI) is a form of acute lung injury characterized by nonspecific alveolar damage and lung edema due to robust inflammation. Little is known about the roles of specialized proresolving lipid mediators (SPMs) in lung IRI. Therefore, we aimed to evaluate the dynamic changes in endogenous SPMs during the initiation and resolution of lung IRI and to determine the effects of SPM supplementation on lung IRI.

METHODS

We used a rat left hilar clamp model with 90 min of ischemia, followed by reperfusion. Dynamic changes in endogenous SPMs were evaluated using liquid chromatography-tandem mass spectrometry.

RESULTS

Endogenous SPMs in the left lung showed a decreasing trend after 1 h of reperfusion. Oxygenation improved between 3 and 7 d following reperfusion; however, the level of endogenous SPMs remained low compared with that in the naïve lung. Among SPM receptors, only formyl peptide receptor type 2 (ALX/FPR2) gene expression in the left lung was increased 3 h after reperfusion, and the inflammatory cells were immunohistochemically positive for ALX/FPR2. Administration of aspirin-triggered (AT) resolvin D1 (AT-RvD1) and AT lipoxin A4 (AT-LXA4), which are agonistic to ALX/FPR2, immediately after reperfusion improved lung function, reduced inflammatory cytokine levels, attenuated lung edema, and decreased neutrophil infiltration 3 h after reperfusion. The effects of AT-RvD1 and AT-LXA4 were not observed after pretreatment with the ALX/FPR2 antagonist.

CONCLUSIONS

The level of intrapulmonary endogenous SPMs decreased during lung IRI process and the administration of AT-RvD1 and AT-LXA4 prevented the exacerbation of lung injury via ALX/FPR2.

Coronavirus disease 2019 positivity immediately after lung transplantation: A case report

Management of COVID-19 in lung transplant recipients is challenging. We report a case of a 71-year-old male who underwent bilateral lung transplantation with an unexpected case of COVID-19. The patient had been fully vaccinated. The patient and donor tested negative for pretransplant COVID-19. On routine bronchoscopy on day 1 after transplant, the COVID-19 test was positive. Mycophenolic mofetil and the second dose of basiliximab were skipped, but tacrolimus and prednisone were continued. He was treated with casirivimab/imdevimab and remdesivir. He was discharged on day 14 and has had no episodes of acute rejection during the 3 months.

Interaction of Eating Status and Dietary Variety on Incident Functional Disability among Older Japanese Adults

OBJECTIVES

To examine whether eating status and dietary variety were associated with functional disability during a 5-year follow-up analysis of older adults living in a Japanese metropolitan area.

DESIGN

A 5-year follow-up study.

SETTING

Ota City, Tokyo, Japan.

PARTICIPANTS

A total of 10,308 community-dwelling non-disabled adults aged 65-84 years.

MEASUREMENTS

Eating status was assessed using a self-reported questionnaire. Dietary variety was assessed using the dietary variety score (DVS). Based on the responses, participants were classified according to eating alone or together and DVS categories (low: 0-3; high: 4-10). Functional disability incidence was prospectively identified using the long-term care insurance system's nationally unified database. Multilevel survival analyses calculated the adjusted hazard ratio (HR) and 95% confidence interval (CI) for incident functional disability.

RESULTS

During a 5-year follow-up, 1,991 (19.3%) individuals had functional disabilities. Eating status or DVS were not independently associated with incident functional disability. However, interaction terms between eating status and DVS were associated with functional disability; HR (95% CI) for eating together and low DVS was 1.00 (0.90-1.11), eating alone and high DVS was 0.95 (0.77-1.17), and eating alone and low DVS was 1.20 (1.02-1.42), compared to those with eating together and high DVS.

CONCLUSION

Older adults should avoid eating alone or increase dietary variety to prevent functional disability. This can be ensured by providing an environment of eating together or food provision services for eating a variety of foods in the community.

Drug repositioning of antipsychotic drugs for cisplatin-induced pica behavior in mice

We aimed to clarify whether various antipsychotics ameliorate cisplatin-induced pica behavior in mice using a drug repositioning approach. Mice were administered cisplatin (12.5 mg/kg, i.p.) with or without olanzapine (1 mg/kg, i.p.), asenapine (4 mg/kg, i.p.), mirtazapine (5 mg/kg, i.p.) or standard three-drug antiemetics (granisetron [0.5 mg/kg, i.p.], fosaprepitant [25 mg/kg, i.p.], and dexamethasone [3 mg/kg, i.p.]). Kaolin, food, and water intake, and spontaneous motor activity on the day before and seven consecutive days after the cisplatin administration were measured using a telemetry system. At the primary endpoint, kaolin intake was significantly higher at day three in the cisplatin group than in the pre-treatment and saline groups ( p < 0.05). Additionally, kaolin intake was not significantly higher in cisplatin with olanzapine, asenapine, and mirtazapine groups for seven days than in the pre-treatment group. At the secondary endpoint, cisplatin decreased the food and water intake, and spontaneous motor activity in a time-dependent manner. Three antipsychotics failed to improve the cisplatin-induced decrease in food and water intake, and spontaneous motor activity. The findings suggest that prophylactic administration of antipsychotics besides olanzapine may improve cisplatin-induced nausea and vomiting in a delayed phase and de-escalate standard 3-drug antiemetics.

A cyclic lipopeptide surfactin is a species-selective Hsp90 inhibitor that suppresses cyanobacterial growth

Heat shock protein 90 (Hsp90) is essential for eukaryotic cells, whereas bacterial homologs play a role under stresses and in pathogenesis. Identifying species-specific Hsp90 inhibitors is challenging because Hsp90 is evolutionarily conserved. We found that a cyclic lipopeptide surfactin inhibits the ATPase activity of Hsp90 from the cyanobacterium Synechococcus elongatus (S. elongatus) PCC 7942 but does not inhibit Escherichia coli (E. coli), yeast and human Hsp90s. Molecular docking simulations indicated that surfactin could bind to the N-terminal dimerization interface of the cyanobacterial Hsp90 in the ATP- and ADP-bound states, which provided molecular insights into the species-selective inhibition. The data suggest that surfactin inhibits a rate-limiting conformational change of S. elongatus Hsp90 in the ATP hydrolysis. Surfactin also inhibited the interaction of the cyanobacterial Hsp90 with a model substrate, and suppressed S. elongatus growth under heat stress, but not that of E. coli. Surfactin did not show significant cellular toxicity toward mammalian cells. These results indicate that surfactin inhibits the cellular function of Hsp90 specifically in the cyanobacterium. The present study shows that a cyclic peptide has a great specificity to interact with a specific homolog of a highly conserved protein family.

Association between Oral Frailty and Dietary Variety among Community-Dwelling Older Persons: A Cross-Sectional Study

OBJECTIVE

To examine the association between the severity of oral frailty (OF), which is one of the comprehensive oral functions evaluated, and dietary variety in community-dwelling older persons.

DESIGN

Cross-sectional study.

SETTING

Community-based.

PARTICIPANTS

A total of 769 community-dwelling older persons aged 65 and over.

INTERVENTIONS

We examined basic demographic information, functional status, cognitive status, depressive symptoms, medical history, and oral functions of the participants.

MEASUREMENTS

OF was defined by 1-2 and 3 or more of 6 items of oral function evaluation in the pre-oral frailty and oral frailty groups, respectively. Dietary variety was assessed using the dietary variety score (DVS). The participants were categorized into 3 groups for evaluation: those with a low score (0-2), medium score (3-5), and high score (≥6). Ordinal logistic regression analysis was performed to examine the association between OF and DVS.

RESULTS

The rate of OF in the participants was 21.6%, and its severity was significantly associated with DVS after adjusting for potential confounders (Pre-OF; adjusted odds ratio [OR] = 1.687, 95% confidence interval [CI] = 1.219-2.335, OF; adjusted OR = 2.857, 95% CI = 1.489-5.484).

CONCLUSION

The severity of OF was significantly associated with DVS in community-dwelling older persons. This suggests that DVS may be useful in understanding the effects of OF on the nutritional status. Further longitudinal studies are needed to elucidate the association between OF and DVS.

Long-term prognosis in patients with non-type 1 Brugada ECG: results from a large Japanese cohort of Brugada syndrome

Background

Most recent consensus conference report recommends Brugada syndrome (BrS) is diagnosed in patients with ST segment elevation with spontaneous, drug-induced or fever-induced type 1 morphology. Prognosis in patients with type 2 or 3 ECG without drug-induced or fever-induced type 1 ECG is still unknown.

Purpose

To evaluate a long-term prognosis in patients with non-type 1 Brugada ECG in a large Japanese cohort of BrS (The Japan Idiopathic Ventricular Fibrillation Study [J-IVFS]).

Methods

From 528 patients in J-IVFS, a total of 28 consecutive non-type 1 patients (54±14 years, all male, previous sustained ventricular tachyarrhythmias (VTs) 1, syncope 11, asymptomatic 16) were enrolled. Cardiac events (CI: sudden cardiac death or VTs) during the follow-up period were evaluated, and risk factors for the cardiac events were assessed.

Results

During a mean follow-up period of 111±91 months (median 134 months), 4 patients experienced cardiac events (1.5%/yr), who all had received implantable cardioverter defibrillator implantation. There was no statistically significant clinical risk factor for cardiac events. However, the incidences of cardiac events tended to be higher in symptomatic patients (CI: 25.0, non-CI: 6.3%, p=0.17), those with wide QRS duration &gt;90 msec in lead V2 (CI: 30.0, non-CI: 6.3%, p=0.11), and those with inducible VTs (CI: 21.1, non-CI: 0%, p=0.20), as determined by the Kaplan-Meier method. The annual incidences of cardiac events in patients with symptom, wide QRS duration &gt;90msec in lead V2, or inducible VTs were 2.8, 3.5, and 2.0%/yr, respectively. The incidences of cardiac events were significantly higher in patients with all these 3 factors (9.9%/yr) than those without (p=0.01).

Conclusions

Our large-scaled multicentre study revealed long-term prognosis in patients with non-type 1 Brugada ECG. The combination of symptom, wide QRS duration in lead V2, and inducible VTs may be useful to evaluate risk for cardiac events. The patients with all these parameters showed high risk for cardiac events and need to be carefully followed.

Funding Acknowledgement

Type of funding source: None

The safety of catheter ablation of atrial fibrillation in elderly patients -analysis of the nationwide database in Japan, JROAD-DPC-

Background

“Age” is one of the major concerns and determinants of the indications for catheter ablation (CA) of atrial fibrillation (AF). There are little safety data on CA of AF according to the age. This study aimed to assess the safety of CA in elderly patients undergoing CA of AF.

Methods and results

We investigated the complication rate of CA of AF for the different age groups (&lt;60 years, 60–65, 65–70, 70–75, 75–80, 80–85, and ≥85) by a nationwide database (Japanese Registry Of All cardiac and vascular Diseases [JROAD]-DPC). The JROAD-DPC included 73,296 patients (65±11 years, 52,883 men) who underwent CA of AF from 516 hospitals in Japan. Aged patients had more comorbidities and a significantly increased CHADS2 score and higher rate of female according to a higher age. The overall complication rate was 2.6% and in-hospital mortality was 0.05%. By comparing each age group, complications occurred more frequently in higher aged groups. A multivariate adjusted hazard ratio revealed an increased age was independently and significantly associated with the overall complications (odds ratio was 1.25, 1.35, 1.72, 1.86, 2.76 and 3.13 respectively; reference &lt;60 years).

Conclusions

The frequency of complications was significantly higher according to a higher age. We should take note of the indications and procedure for CA of AF in aged patients.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Intramural Research Fund 17 (Kusano) for Cardiovascular Diseases of the National Cerebral and Cardiovascular Center

The treatment and survival of patients with postoperative recurrent thymic carcinoma and neuroendocrine carcinoma: a multicenter retrospective study

PURPOSE

There are few data available on the outcomes of postoperative recurrent thymic carcinoma (TC) and thymic neuroendocrine carcinoma (TNEC). The aim of this study is to evaluate the treatment and survival in patients with recurrent TC and TNEC after undergoing surgical resection.

METHODS

A retrospective chart review was performed using our multicenter database to identify patients with a postoperative recurrence of TC and TNEC from 1995 to 2018. The clinicopathological factors were reviewed and the survival outcomes were analyzed.

RESULTS

Sixty patients were identified among 152 patients who underwent resection of TC and TNEC. The median follow-up period from the first recurrence was 14.8 months (range 0-144). The 5-year post-recurrence survival was 23% for the whole cohort. According to a univariable analysis, advanced stage [hazard ratio (HR) 2.81, 95% confidence interval (CI) 1.09-9.54], interval between primary surgery and recurrence (HR 0.97, 95% CI 0.95-0.99), any treatment for recurrence (HR: 0.27, 95% CI 0.13-0.58) and chemotherapy for recurrence (HR: 0.46, 95% CI 0.22-0.95) were significant factors related to post-recurrence survival.

CONCLUSIONS

Chemotherapy rather than surgery appears to be the mainstay treatment for managing patients with postoperative recurrent TC and TNEC and it may also be considered in multidisciplinary management. Further studies with a larger sample size are required to confirm our findings.

Are volume-dependent parameters in positron emission tomography predictive of postoperative recurrence after resection in patients with thymic carcinoma?

This study aimed to investigate the association between the volume-dependent parameters in ¹⁸F-fluorodeoxyglucose-positron emission tomography (¹⁸F-FDG PET/CT) and a recurrence of thymic carcinoma. A retrospective chart review was performed based on our multi-institutional database to identify patients undergoing PET prior to resection of thymic carcinoma or neuroendocrine carcinoma between 1991 and 2018. The PET parameters (metabolic tumor volume and total lesion glycolysis) were evaluated retrospectively. The relevant factors were extracted and a survival analysis was performed using the Kaplan-Meier method. Sixteen patients were thus deemed to be eligible for analysis. The median follow-up period following resection was 2.65 years (range: 0.96-0.68 years). The recurrence-free survival was significantly longer in patients with a metabolic tumor volume <  = 22.755 cm³ and with total lesion glycolysis <  = 105.4006 g/mL (p = 0.001 and 0.001, respectively, by a log-rank test). The metabolic tumor volume and total lesion glycolysis may, therefore, be predictive of the postoperative recurrence of thymic carcinoma.

High Pressure Quenched Glasses: unique structures and properties

Zr-based metallic glasses are prepared by quenching supercooled liquid under pressure. These glasses are stable in ambient conditions after decompression. The High Pressure Quenched glasses have a distinct structure and properties. The pair distribution function shows redistribution of the Zr-Zr interatomic distances and their shift towards smaller values. These glasses exhibit higher density, hardness, elastic modulus, and yield stress. Upon heating at ambient pressure, they show volume expansion and distinct relaxation behavior, reaching an equilibrated state above the glass transition. These experimental results are consistent with an idea of pressure-induced low to high density liquid transition in the supercooled melt.

Protective effects of a hydrogen-rich solution during cold ischemia in rat lung transplantation

BACKGROUND

Molecular hydrogen can reduce the oxidative stress of ischemia-reperfusion injury in various organs for transplantation and potentially improve survival rates in recipients. This study aimed to evaluate the protective effects of a hydrogen-rich preservation solution against ischemia-reperfusion injury after cold ischemia in rat lung transplantation.

METHODS

Lewis rats were divided into a nontransplant group (n = 3), minimum-ischemia group (n = 3), cold ischemia group (n = 6), and cold ischemia with hydrogen-rich (more than 1.0 ppm) preservation solution group (n = 6). The rats in the nontransplant group underwent simple thoracotomy, and the rats in the remaining 3 groups underwent orthotopic left lung transplantation. The ischemic time was <30 minutes in the minimum-ischemia group and 6 hours in the cold ischemia groups. After 2-hour reperfusion, we evaluated arterial blood gas levels, pulmonary function, lung wet-to-dry weight ratio, and histologic features of the lung tissue. The expression of proinflammatory cytokines was measured using quantitative polymerase chain reaction assays, and 8-hydroxydeoxyguanosine levels were evaluated using enzyme-linked immunosorbent assays.

RESULTS

When compared with the nontransplant and minimum-ischemia groups, the cold ischemia group had lower dynamic compliance, lower oxygenation levels, and higher wet-to-dry weight ratios. However, these variables were significantly improved in the cold ischemia with hydrogen-rich preservation solution group. This group also had fewer signs of perivascular edema, lower interleukin-1β messenger RNA expression, and lower 8-hydroxydeoxyguanosine levels than the cold ischemia group.

CONCLUSIONS

The use of a hydrogen-rich preservation solution attenuates ischemia-reperfusion injury in rat lungs during cold ischemia through antioxidant and anti-inflammatory effects.

A multicenter, randomized, rater-blinded, parallel-group, phase 3 study to compare the efficacy, safety, and immunogenicity of biosimilar RGB-10 and reference once-daily teriparatide in patients with osteoporosis

The efficacy and safety of RGB-10 and reference teriparatide were evaluated in a randomized 52-week study in 250 patients with osteoporosis at high risk of fracture. RGB-10 was equivalent to reference teriparatide in efficacy and had a comparable safety profile.

INTRODUCTION

RGB-10 is the first biosimilar teriparatide authorized in the European Union. This multicenter, randomized, rater-blinded, parallel-group phase 3 study evaluated equivalence in efficacy and compared safety between RGB-10 and reference teriparatide in patients with osteoporosis at high risk of fracture for registration in Japan.

METHODS

Ambulatory postmenopausal women and men (≥ 55 years of age) with osteoporosis at high risk of fracture were randomized 1:1 to receive either RGB-10 or reference teriparatide 20 μg once daily via subcutaneous self-injection for 52 weeks. The primary efficacy endpoint was the percent change from baseline to 52 weeks in lumbar spine (L2-L4) bone mineral density (BMD). Safety outcomes and immunogenicity were also assessed.

RESULTS

In total, 250 patients (125 in each group) were randomized. The percent change from baseline to 52 weeks in lumbar spine (L2-L4) BMD (mean ± standard deviation) was 8.94% ± 6.19% in the RGB-10 group and 9.65% ± 6.22% in the reference teriparatide group. The estimated between-group difference (95% confidence interval) was - 0.65% (- 2.17% to - 0.87%) within the pre-specified equivalence margin (± 2.8%), which indicates equivalence in efficacy between the two groups. Changes in BMD at lumbar spine (L1-L4), femoral neck, and total hip and serum procollagen type I amino-terminal propeptide were also similar between the groups. Safety profiles, including immunogenicity, were comparable.

CONCLUSIONS

The therapeutic equivalence of RGB-10 to reference teriparatide was demonstrated. RGB-10 had comparable safety profile to that of reference teriparatide.

P5029Inducibility of ventricular tachyarrhythmias by up to two extrastimuli does not predict future cardiac events in asymptomatic Brugada patients: results from long-term follow-up

Background

Most recent consensus conference report recommends Implantable Cardioverter Defibrillator (ICD) implantation for asymptomatic Brugada patients with spontaneous or fever-induced type-1 ECG (A-BrS) and inducible ventricular tachyarrhythmias (VTs) by up to two extrastimuli as class IIb indication. However, the validity of the inducible VTs by up to two extrastimuli in A-BrS is still unknown.

Purpose

To evaluate the validity of the inducibility by up to two extrastimuli in A-BrS in a large Japanese cohort of BrS (The Japan Idiopathic Ventricular Fibrillation Study [J-IVFS]).

Methods

A total of 193 consecutive A-BrS patients performed programmed electrical stimulation (PES) with non-aggressive uniform protocol (mean age 50±13 years, 180 males) were enrolled. PES protocol was using 2 basic pacing cycles and the order of introduction of up to 2 ventricular extra-stimuli from right ventricular apex [RVA] first, then right ventricular outflow tract [RVOT], 3 ventricular extra-stimuli from RVA then RVOT down to the minimum of 200ms. Clinical outcomes during the follow-up period were compared between A-BrS patients with and without inducible VTs by up to two extrastimuli.

Results

Thirty-five A-BrS (18%) had inducible VTs by up to two extrastimuli. During a mean follow-up period of 101±48 months, 7 A-BrS experienced cardiac events (sudden cardiac death [SCD] or VTs, 0.4%/yr). None of the 7 A-BrS had inducible VTs by up to two extrastimuli. The incidences of cardiac events tended to be higher in A-BrS without inducible VTs by up to two extrastimuli than in those with inducible VTs (p=0.10), as determined by the Kaplan-Meier method. In the A-BrS, the annual incidences of cardiac events in A-BrS with family history of SCD, inferolateral J wave, wide QRS duration >90msec in lead V2, or inducible VT/VF by 3 extrastimuli were 0.7, 0.7, 0.6, and 0.3%/yr, respectively.

Conclusions

Our large-scaled multicentre study with long-term follow-up revealed the inducibility of ventricular tachyarrhythmias by up to two extrastimuli does not predict future cardiac events in A-BrS, even using non-aggressive uniform protocol. Rather, other parameters such as family history of SCD or inferolateral J wave might be helpful for risk assessment in A-BrS.

Benign hilar bile duct strictures resected as perihilar cholangiocarcinoma

BACKGROUND

Differentiation between perihilar cholangiocarcinoma (PHCC) and benign strictures is frequently difficult. The aim of this study was to investigate the incidence and long-term outcome of patients with tumours resected because of suspicion of PHCC, which ultimately turned out to be benign (malignancy masquerade).

METHODS

Patients who underwent surgical resection with a diagnosis of PHCC between 2001 and 2016 were reviewed retrospectively.

RESULTS

Among 707 consecutive patients, 685 had PHCC and the remaining 22 (3·1 per cent) had benign biliary stricture. All patients with benign disease underwent major hepatectomy, with no deaths. Preoperative histological assessment using bile duct biopsy or aspiration cytology had a high specificity (90 per cent), low sensitivity (62 per cent) and unsatisfactory accuracy (63 per cent). Despite the increasing use of histological assessment, the incidence of benign strictures resected did not decrease over time, being 0·9 per cent in 2001-2004, 4·0 per cent in 2005-2008, 3·8 per cent in 2009-2012 and 2·9 per cent in 2013-2016. The final pathology of benign strictures included IgG4-related sclerosing cholangitis (9 patients), hepatolithiasis (4), granulomatous cholangitis (3), non-specific chronic cholangitis (3), benign strictures after cholecystectomy (2), and a benign stricture possibly caused by parasitic infection (1). The 10-year overall survival rate for the 22 patients with benign stricture was 87 per cent, without recurrence of biliary stricture.

CONCLUSION

The incidence of benign strictures resected as PHCC as a proportion of all resections was relatively low, at 3·1 per cent. Currently, unnecessary surgery for suspected PHCC is unavoidable.

Clinical value of additional resection of a margin-positive distal bile duct in perihilar cholangiocarcinoma

Background

Little is known about the effect of additional resection for a frozen-section-positive distal bile duct margin (DM) in perihilar cholangiocarcinoma.

Methods

Patients who underwent surgical resection for perihilar cholangiocarcinoma between 2001 and 2015 were analysed retrospectively, focusing on the DM.

Results

Of 558 consecutive patients who underwent frozen-section examination for a DM, 74 (13·3 per cent) had a frozen-section-positive DM with invasive cancer or carcinoma in situ. Eventually, 53 patients underwent additional resection (bile duct resection in 44 and pancreatoduodenectomy in 9), whereas the remaining 21 patients did not. Ultimately, R0 resection was achieved in 30 of the 53 patients (57 per cent). No patient who underwent additional resection died from surgical complications. The 44 patients with additional bile duct resection had a 5-year overall survival rate of 31 per cent. Overall survival of the nine patients who had pancreatoduodenectomy was better, with a 10-year rate of 67 per cent. Survival of the 21 patients without additional resection was dismal: all died within 5 years. Multivariable analyses identified nodal status and additional resection as independent prognostic factors (lymph node metastasis: hazard ratio (HR) 2·26, 95 per cent c.i. 1·26 to 4·07; bile duct resection versus no additional resection: HR 0·32, 0·17 to 0·60; pancreatoduodenectomy versus no additional resection: HR 0·08, 0·02 to 0·29).

Conclusion

Additional resection for frozen-section-positive DM in perihilar cholangiocarcinoma frequently yields R0 margins. It offers a better chance of long-term survival, and thus should be performed in carefully selected patients.

Major hepatectomy with or without pancreatoduodenectomy for advanced gallbladder cancer

BACKGROUND

The indications for major hepatectomy for gallbladder cancer either with or without pancreatoduodenectomy remain controversial. The clinical value of these extended procedures was evaluated in this study.

METHODS

Patients who underwent major hepatectomy for gallbladder cancer between 1996 and 2016 were identified from a prospectively compiled database. Postoperative outcomes and overall survival were compared between patients undergoing major hepatectomy alone or combined with pancreatoduodenectomy (HPD).

RESULTS

Seventy-nine patients underwent major hepatectomy alone and 38 patients had HPD. The patients who underwent HPD were more likely to have T4 disease (P < 0·001), nodal metastasis (P = 0·015) and periaortic nodal metastasis (P = 0·006), but were less likely to receive adjuvant therapy (P = 0·006). HPD was associated with a high incidence of grade III or higher complications (P = 0·002) and death (P = 0·037). Overall survival was longer in patients who underwent major hepatectomy alone than in patients who underwent HPD (median survival time 32 versus 10 months; P < 0·001). In multivariable analysis, surgery in the early period (1996-2006) (P = 0·002), pathological T4 disease (P = 0·005) and distant metastasis (P < 0·001) were associated with shorter overall survival, and cystic duct tumour (P = 0·002) with longer overall survival.

CONCLUSION

Major hepatectomy alone for gallbladder cancer contributes to favourable overall survival with low morbidity and mortality, whereas HPD is associated with poor overall survival and high morbidity and mortality rates. HPD may eradicate locally spreading gallbladder cancer; however, the indication for the procedure is questioned from an oncological viewpoint.

Score-Based and Nutrient-Derived Dietary Patterns Are Associated with Depressive Symptoms in Community-Dwelling Older Japanese: A Cross-Sectional Study

OBJECTIVES

This study evaluated associations of score-based and nutrient-derived dietary patterns with depressive symptoms in community-dwelling older Japanese.

DESIGN

Cross-sectional study.

SETTING

Community-based.

PARTICIPANTS

982 community-dwelling adults aged 65 years or older.

MEASUREMENTS

Score-based pattern was assessed by using dietary variety score (DVS), which covers 10 food group items in Japanese meals. Nutrient-derived dietary patterns were identified by using reduced rank regression (RRR), with folate, vitamin C, magnesium, calcium, iron, and zinc intakes as response variables. Depressive symptoms were assessed with the Geriatric Depression Scale. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for these dietary patterns in multivariate logistic regression analyses with potential confounders. The lowest consumption category was used as the reference group.

RESULTS

The prevalence of depressive symptoms was 13.5%. Higher DVS was associated with fewer depressive symptoms (OR=0.52, 95% CI=0.27-1.03 for the highest vs the lowest DVS; P for trend=0.031). The first RRR dietary pattern score was characterized by high intakes of fish, soybean products, potatoes, most vegetables, mushrooms, seaweeds, fruits, and green tea and a low intake of rice and was inversely associated with the prevalence of depressive symptoms (OR=0.53, 95% CI=0.30-0.92; P for trend=0.030).

CONCLUSION

Greater dietary variety and a dietary pattern characterized by high intakes of fish, soybean products, potatoes, most vegetables, mushrooms, seaweeds, fruit, and green tea and a low intake of rice were consistently associated with lower prevalence of depressive symptoms in community-dwelling older Japanese. Therefore, both patterns identified the components of dietary habits essential to depression prevention.

Albumin, Hemoglobin, and the Trajectory of Cognitive Function in Community-Dwelling Older Japanese: A 13-Year Longitudinal Study

BACKGROUND

Cognitive function can substantially decline over a long period, and understanding the trajectory of cognitive function is important. However, little is known about the linkage between nutritional biomarkers and long-term cognitive change.

OBJECTIVES

We analyzed 13-year longitudinal data for older Japanese to examine the associations of serum albumin and hemoglobin levels with the trajectory of cognitive function.

DESIGN

Longitudinal study.

SETTING

Community-based.

PARTICIPANTS

A total of 1,744 community-dwelling adults aged 65 years or older who participated in annual health examinations in Kusatsu town, Gunma Prefecture, Japan, from 2002-2014.

MEASUREMENTS

Cognitive function was assessed annually by the Mini-Mental State Examination (MMSE). Albumin and hemoglobin levels at baseline (the year when a respondent first participated in the health examination) were divided into quartiles. Hierarchical linear modeling was used to analyze intrapersonal and interpersonal differences in cognitive function.

RESULTS

Participants' MMSE scores decreased at an accelerated rate over the 13-year period. Participants with the lowest baseline albumin level (below the first quartile line) showed a greater accelerated decline in MMSE scores over time, compared with those with the highest level (above the third quartile line). Moreover, MMSE scores in participants with a lower hemoglobin level and lower MMSE score at baseline tended to decline faster over time at an accelerated rate.

CONCLUSIONS

These findings yield new insights about the complex and diverse roles of these nutritional biomarkers on the trajectory of cognitive function in old age.

Formation of stromatolite lamina at the interface of oxygenic-anoxygenic photosynthesis

In modern stromatolites, mineralization results from a complex interplay between microbial metabolisms, the organic matrix, and environmental parameters. Here, we combined biogeochemical, mineralogical, and microscopic analyses with measurements of metabolic activity to characterize the mineralization processes and products in an emergent (<18 months) hypersaline microbial mat. While the nucleation of Mg silicates is ubiquitous in the mat, the initial formation of a Ca-Mg carbonate lamina depends on (i) the creation of a high-pH interface combined with a major change in properties of the exopolymeric substances at the interface of the oxygenic and anoxygenic photoautotrophic layers and (ii) the synergy between two major players of sulfur cycle, purple sulfur bacteria, and sulfate-reducing bacteria. The repetition of this process over time combined with upward growth of the mat is a possible pathway leading to the formation of a stromatolite.

Electronic Structure of Ce-Doped and -Undoped Nd_{2}CuO_{4} Superconducting Thin Films Studied by Hard X-Ray Photoemission and Soft X-Ray Absorption Spectroscopy

In order to realize superconductivity in cuprates with the T^{'}-type structure, not only chemical substitution (Ce doping) but also postgrowth reduction annealing is necessary. In the case of thin films, however, well-designed reduction annealing alone without Ce doping can induce superconductivity in the T^{'}-type cuprates. In order to unveil the origin of superconductivity in the Ce-undoped T^{'}-type cuprates, we have performed bulk-sensitive hard x-ray photoemission and soft x-ray absorption spectroscopy on superconducting and nonsuperconducting Nd_{2-x}Ce_{x}CuO_{4} (x=0, 0.15, and 0.19) thin films. By postgrowth annealing, core-level spectra exhibited dramatic changes, which we attributed to the enhancement of core-hole screening in the CuO_{2} plane and the shift of chemical potential along with changes in the band filling. The result suggests that the superconducting Nd_{2}CuO_{4} film is doped with electrons despite the absence of the Ce substitution.

Tensile-Strain-Dependent Spin States in Epitaxial LaCoO_{3} Thin Films

The spin states of Co^{3+} ions in perovskite-type LaCoO_{3}, governed by the complex interplay between the electron-lattice interactions and the strong electron correlations, still remain controversial due to the lack of experimental techniques which can directly detect them. In this Letter, we revealed the tensile-strain dependence of spin states, i.e., the ratio of the high- and low-spin states, in epitaxial thin films and a bulk crystal of LaCoO_{3} via resonant inelastic soft x-ray scattering. A tensile strain as small as 1.0% was found to realize different spin states from that in the bulk.

Associations between birth size and later height from infancy through adulthood: An individual based pooled analysis of 28 twin cohorts participating in the CODATwins project

BACKGROUND

There is evidence that birth size is positively associated with height in later life, but it remains unclear whether this is explained by genetic factors or the intrauterine environment.

AIM

To analyze the associations of birth weight, length and ponderal index with height from infancy through adulthood within mono- and dizygotic twin pairs, which provides insights into the role of genetic and environmental individual-specific factors.

METHODS

This study is based on the data from 28 twin cohorts in 17 countries. The pooled data included 41,852 complete twin pairs (55% monozygotic and 45% same-sex dizygotic) with information on birth weight and a total of 112,409 paired height measurements at ages ranging from 1 to 69 years. Birth length was available for 19,881 complete twin pairs, with a total of 72,692 paired height measurements. The association between birth size and later height was analyzed at both the individual and within-pair level by linear regression analyses.

RESULTS

Within twin pairs, regression coefficients showed that a 1-kg increase in birth weight and a 1-cm increase in birth length were associated with 1.14-4.25 cm and 0.18-0.90 cm taller height, respectively. The magnitude of the associations was generally greater within dizygotic than within monozygotic twin pairs, and this difference between zygosities was more pronounced for birth length.

CONCLUSION

Both genetic and individual-specific environmental factors play a role in the association between birth size and later height from infancy to adulthood, with a larger role for genetics in the association with birth length than with birth weight.

Ethanol ablation for refractory bile leakage after complex hepatectomy

BACKGROUND

Only a few reports exist on the use of ethanol ablation for posthepatectomy bile leakage. The aim of this study was to assess the value of ethanol ablation in refractory bile leakage.

METHODS

Medical records of consecutive patients who underwent a first hepatobiliary resection with bilioenteric anastomosis between 2007 and 2016 were reviewed retrospectively, with special attention to bile leakage and ethanol ablation therapy. Bile leakage was graded as A/B1/B2 according to the International Study Group of Liver Surgery definition. Absolute ethanol was injected into the target bile duct during fistulography.

RESULTS

Of the 609 study patients, 237 (38·9 per cent) had bile leakage, including grade A in 33, grade B1 in 18 and grade B2 in 186. Left trisectionectomy was more often associated with grade B2 bile leakage than other types of hepatectomy (P < 0·001). Of 186 patients with grade B2 bile leakage, 31 underwent ethanol ablation therapy. Ethanol ablation was started a median of 34 (range 15-122) days after hepatectomy. The median number of treatments was 3 (1-7), and the total amount of ethanol used was 15 (3-71) ml. Complications related to ethanol ablation included transient fever (27 patients) and mild pain (13). Following ethanol ablation, bile leakage resolved in all patients and drains were removed. The median interval between the first ablation and drain removal was 28 (1-154) days.

CONCLUSION

Ethanol ablation is safe and effective, and may be a treatment option for refractory bile leakage.

Elastostatic reversibility in thermally formed bulk metallic glasses: nanobeam diffraction fluctuation electron microscopy

The unparalleled shaping ability of bulk metallic glasses can revolutionize commercial products having multi-length scale features with a processing time of several minutes. Despite the widespread shaping ability of these polymer-like multicomponent alloys, thermoplastic forming (TPF) can severely degrade the intrinsic properties, particularly when complex stress states are activated. The present work emphasizes the importance of elastostatic loading (ESL) which not only fully reverses deteriorated room temperature plasticity originating under TPF or post-cryostatic conditions, but also activates a rejuvenation mechanism by rendering an extended resistance against strain softening. Furthermore, the reduction in the supercooled liquid region and crystallization enthalpy measured by differential scanning calorimetry are found to be temporary, and can be fully reversed to the initial condition. HRTEM imaging of the samples are performed with an imaging spherical aberration corrector. Individual nanobeam diffraction patterns obtained by the fluctuation electron microscopy (FEM) measurements are acquired using a scanning transmission electron microscope with a probe size of 1.2 nm from a 10 × 10 raster, yielding 100 diffraction patterns. The normalized variance of a series of nanodiffraction patterns of the post-elastostatically loaded sample reveals a height decrease in the first broad peak of normalized intensity variance V(k) suggesting modifications in the medium-range structural order which in turn dramatically restores the mechanical and thermal properties. Overall, the combination of TPF and post-ESL treatment in advanced glassy metals can open a new avenue for ultra-high mechanical and thermal performance micro- and nanomechanical devices for biosensors, MOSFETs and robotics.

CFD Simulation of a Novel Bileaflet Mechanical Heart Valve Prosthesis - An Estimation of the Venturi Passage Formed by the Leaflets

The aim of this study was to validate the flow characteristics of the novel Helmholtz-Institute Aachen Bileaflet (HIA-BL) heart valve prosthesis. The curved leaflets of the HIA-BL valve form a Venturi passage between the leaflets at peak systole. By narrowing the cross section the flow accelerates and the static pressure at the central passage decreases according to the Venturi effect. The low-pressure zone between the leaflets is expected to stabilize the leaflets in fully open position at peak systole.

To investigate the Venturi passage, the flow fields of two valve geometries were investigated by CFD (Computational Fluid Dynamics): one geometry exhibits curved leaflets resulting in a Venturi passage; the other geometry features straight leaflets. The flow profiles, pressure distribution and resulting torque of both passages were compared and investigated.

Although flow profiles downstream of both valves were similar, the flow passages between the leaflets were different for the investigated leaflet geometries. The straight leaflet passage showed a large boundary layer separation zone near the leaflets and the lowest pressure at the leading edge of the leaflet. The Venturi passage showed a reduction of the boundary layer separation zones and the lowest pressure between the leaflets could be found in the narrowest flow cross section of the Venturi passage. Additionally, the resulting torque showed that the Venturi passage produced an opening momentum. The results demonstrate that the Venturi passage stabilizes the leaflets in open position at peak systole.

Effects of Low-Dose Dairy Protein Plus Micronutrient Supplementation during Resistance Exercise on Muscle Mass and Physical Performance in Older Adults: A Randomized, Controlled Trial

OBJECTIVES

To investigate whether supplementation with low-dose dairy protein plus micronutrients augments the effects of resistance exercise (RE) on muscle mass and physical performance compared with RE alone among older adults.

DESIGN

Randomized controlled trial.

SETTING

Tokyo, Japan.

PARTICIPANTS

Eighty-two community-dwelling older adults (mean age, 73.5 years) were randomly allocated to an RE plus dairy protein and micronutrient supplementation group or an RE only group (n = 41 each).

INTERVENTION

The RE plus supplementation group participants ingested supplements with dairy protein (10.5 g/day) and micronutrients (8.0 mg zinc, 12 μg vitamin B12, 200 μg folic acid, 200 IU vitamin D, and others/day). Both groups performed the same twice-weekly RE program for 12 weeks.

MEASUREMENTS

Whole-body, appendicular, and leg lean soft-tissue mass (WBLM, ALM, and LLM, respectively) with dual-energy X-ray absorptiometry, physical performance, biochemical characteristics, nutritional intake, and physical activity were measured before and after the intervention. Data were analyzed by using linear mixed-effects models.

RESULTS

The groups exhibited similar significant improvements in maximum gait speed, Timed Up-and-Go, and 5-repetition and 30-s chair stand tests. As compared with RE only, RE plus supplementation significantly increased WBLM (0.63 kg, 95% confidence interval [CI]: 0.31-0.95), ALM (0.37 kg, 95% CI: 0.16-0.58), LLM (0.27 kg, 95% CI: 0.10-0.46), and serum concentrations of 25-hydroxyvitamin D (4.7 ng/mL, 95% CI: 1.6-7.9), vitamin B12 (72.4 pg/mL, 95% CI: 12.9-131.9), and folic acid (12.9 ng/mL, 95% CI: 10.3-15.5) (all P < 0.05 for group-by-time interactions). Changes over time in physical activity and nutritional intake excluding the supplemented nutrients were similar between groups.

CONCLUSION

Low-dose dairy protein plus micronutrient supplementation during RE significantly increased muscle mass in older adults but did not further improve physical performance.

Three-dimensional imaging for thoracoscopic resection of complex lung anomalies

Background

Building surgical strategies for complex lung anomalies such as congenital pulmonary venolobar syndrome is difficult because of their rarity and variance. Using three-dimensional computed tomography (3D–CT), we can determine strategies safely. We describe a 27-year-old man with multifocal pulmonary malformations who underwent video-assisted thoracoscopic surgery (VATS) using 3D–CT.

Case presentation

A 27-year-old man presented with hemoptysis associated with complex pulmonary malformations, including a triple-arched vein connecting the superior and inferior pulmonary veins with partial drainage into the inferior vena cava, a systemic and numerous arterial supply to the right lower lobe from the abdominal aorta, abnormal lobulation, and a tracheal bronchus in the right lung. Preoperative simulation using 3D–CT helped to determine the optimal surgical strategy, allowing for successful and safe completion of semi-emergent middle and lower bilobectomy via minimally invasive VATS.

Conclusions

Preoperative simulation using 3D–CT helped to determine the optimal surgical strategy, allowing for successful and safe completion of surgery even in a complex case.