The Kinematics of Proal Chewing in Rats

Chewing kinematics are well-documented in several mammal species with fused mandibular symphyses, but relatively understudied in mammals with an unfused symphysis, despite the fact that more than half of extant Mammalia have an unfused mandibular symphysis. The Wistar brown rat (Rattus norvegicus) is widely used in human health research, including studies of mastication or neurological studies where mastication is the output behavior. These animals are known to have unfused mandibular symphyses and proal jaw (rostrocaudal) motion during occlusion, but the lack of high resolution, 3-dimensional analysis of rat chewing leaves the functional significance of symphyseal mobility unknown. We used biplanar fluoroscopy and the X-ray reconstruction of moving morphology workflow to quantify chewing kinematics in 3 brown rats, quantifying overall jaw kinematics, including motions about the temporomandibular joint and unfused mandibular symphysis. During occlusion, the teeth and the mandibular condyle translate almost exclusively anteriorly (proal) during occlusion, with little motion in any other degrees of freedom. At the symphysis, we observed minimal flexion throughout the chew cycle. Overall, there are fundamental differences in jaw kinematics between rats and other mammals and therefore rats are not an appropriate proxy for ancestral mammal jaw mechanics. Additionally, differences between humans and rat chewing kinematics must be considered when using rats as a clinical model for pathological feeding research.

Isotropy of Cosmic Rays beyond 10^{20} eV Favors Their Heavy Mass Composition

We report an estimation of the injected mass composition of ultrahigh energy cosmic rays (UHECRs) at energies higher than 10 EeV. The composition is inferred from an energy-dependent sky distribution of UHECR events observed by the Telescope Array surface detector by comparing it to the Large Scale Structure of the local Universe. In the case of negligible extragalactic magnetic fields (EGMFs), the results are consistent with a relatively heavy injected composition at E∼10  EeV that becomes lighter up to E∼100  EeV, while the composition at E>100  EeV is very heavy. The latter is true even in the presence of highest experimentally allowed extragalactic magnetic fields, while the composition at lower energies can be light if a strong EGMF is present. The effect of the uncertainty in the galactic magnetic field on these results is subdominant.

Oxomollugin, an oxidized substance in mollugin, inhibited LPS-induced NF-κB activation via the suppressive effects on essential activation factors of TLR4 signaling

Oxomollugin is a degraded product of mollugin and was found to be an active compound that inhibits LPS-induced NF-κB activation. In this study, we investigated the inhibitory activity of oxomollugin, focusing on TLR4 signaling pathway, resulting in NF-κB activation. Oxomollugin inhibited the LPS-induced association of essential factors for initial activation of TLR4 signaling, MyD88, IRAK4 and TRAF6. Furthermore, oxomollugin showed suppressive effects on LPS-induced modification of IRAK1, IRAK2 and TRAF6, LPS-induced association of TRAF6-TAK1/TAB2, and followed by IKKα/β phosphorylation, which critical in signal transduction leading to LPS-induced NF-κB activation. The consistent results suggested that oxomollugin inhibits LPS-induced NF-κB activation via the suppression against signal transduction in TLR4 signaling pathway.The activities of oxomollugin reported in this study provides a deeper understanding on biological activity of mollugin derivatives as anti-inflammatory compounds.

Prognostic Impact of Stromal Profiles Educated by Gastric Cancer

BACKGROUND

Cancer-associated fibroblasts exhibit diversity and have several subtypes. The underlying relationship between the diversity of cancer-associated fibroblasts and their effect on gastric cancer progression remains unclear. In this study, mesenchymal stem cells were differentiated into cancer-associated fibroblasts with gastric cancer cell lines; clinical specimens were used to further investigate the impact of cancer-associated fibroblast diversity on cancer progression.

METHODS

Nine gastric cancer cell lines (NUGC3, NUGC4, MKN7, MKN45, MKN74, FU97, OCUM1, NCI-N87, and KATOIII) were used to induce mesenchymal stem cell differentiation into cancer-associated fibroblasts. The cancer-associated fibroblasts were classified based on ACTA2 and PDPN expression. Cell function analysis was used to examine the impact of cancer-associated fibroblast subtypes on cancer cell phenotype. Tissue samples from 97gastric patients who underwent gastrectomy were used to examine the clinical significance of each subtype classified according to cancer-associated fibroblast expression.

RESULTS

Co-culture of mesenchymal stem cells with nine gastric cancer cell lines revealed different subtypes of ACTA2 and PDPN expression in differentiated cancer-associated fibroblasts. Cancer-associated fibroblast subtypes with high ACTA2 plus PDPN expression levels significantly increased gastric cancer cell migration, invasion, and proliferation. The cancer-associated fibroblast subtype with ACTA2 plus PDPN expression was an independent prognostic factor along with lymph node metastasis for patients who had gastric cancer and were undergoing surgery.

CONCLUSIONS

Cancer-associated fibroblasts are educated by gastric cancer cells during the development of cancer-associated fibroblast diversity. Differentiated cancer-associated fibroblasts with distinct expression patterns could affect gastric cancer progression and enable prognostic stratification for gastric cancer.

Investigating Cytoglobin Expression in Colon Cancer: Clinicopathological Insights from Immunohistochemical Analysis

BACKGROUND/AIM

Cytoglobin (Cygb), a protein involved in cellular oxygen metabolism and protection, has garnered attention owing to its potential role in the initiation and progression of cancer, particularly colon cancer (CC). This study investigated the expression and significance of Cygb in CC.

PATIENTS AND METHODS

This study included 145 patients who underwent R0 surgery for CC (clinical stage II/III) at our institution between January 2007 and December 2014. Immunohistochemical analysis was performed to evaluate the Cygb expression patterns in CC tissues. Additionally, the correlation between Cygb expression levels and the clinicopathological characteristics of patients with CC was investigated.

RESULTS

Colon cancer tissues were categorized into high-expression (95 cases) and low-expression (50 cases) groups. Cygb was highly expressed in well-differentiated cases, whereas its expression decreased in poorly differentiated cases. No significant differences in other clinicopathological factors were observed between the two groups. Cygb expression had no significant effect on recurrence-free survival or overall survival.

CONCLUSION

This study contributes to the growing understanding of Cygb expression and its significance in CC. The expression of Cygb in CC was found to be unrelated to the recurrence rate and prognosis, but showed a correlation with differentiation status.

Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Serum Creatinine-Cystatin C Based Screening of Sarcopenia in Community Dwelling Older Adults: A Cross-Sectional Analysis

OBJECTIVES

To compare the discriminative capabilities for the manifestation of sarcopenia or physical frailty between serum creatinine- and cystatin C-derived indices among community-dwelling older adults.

DESIGN

Cross-sectional study.

SETTING

Primary Care and Community.

PARTICIPANTS

We utilized a subset of data from the Frail Elderly in the Sasayama-Tamba Area (FESTA) study, which was initiated in 2015 to gather comprehensive information on various health-related parameters among community-dwelling older individuals (age ≥65 years).

MEASUREMENTS

Five serum creatinine-cystatin C based indices including the Sarcopenia Index, the serum creatinine/cystatin C ratio, the disparity between serum cystatin-C-based and creatinine-based estimated GFR, the total body muscle mass index (TBMM), and the prediction equation for skeletal muscle mass index (pSMI) were employed. Sarcopenia and physical frailty were identified based on the Asian Working Group for Sarcopenia criteria and the revised Japanese version of the Cardiovascular Health Study criteria, respectively. The receiver operating characteristic (ROC) and logistic regression analyses were performed to assess the discriminative abilities of these tools.

RESULTS

In the analysis of 954 participants, 52 (5.5%) were identified with sarcopenia and 35 (3.7%) with physical frailty. Regarding sarcopenia discrimination, TBMM and pSMI both exhibited area under the curve (AUC) values exceeding 0.8 for both men and women. Concerning the identification of physical frailty, AUC values ranged from 0.61 to 0.77 for males and 0.50 to 0.69 for females. In the multivariate logistic regression analyses, only TBMM and pSMI consistently displayed associations with sarcopenia, irrespective of sex (P<0.001, respectively). On the other hand, no consistent associations were observed between the indices and physical frailty.

CONCLUSIONS

This study provides a robust association of a serum creatinine- and cystatin C-derived indices, especially TBMM and pSMI, with sarcopenia among community-dwelling older adults. Conversely, the application of these indices for the screening of physical frailty has its constraints, necessitating further investigation.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Current treatment status of IgA nephropathy in Japan: a questionnaire survey

BACKGROUND

In 2020, the Committee of Clinical Practical Guideline for IgA Nephropathy (IgAN) revised the clinical practice guidelines. Herein, we conducted a questionnaire survey to assess the potential discrepancies between clinical practice guidelines and real-world practice in Japan.

METHODS

A web-based survey of members of the Japanese Society of Nephrology was conducted between November 15 and December 28, 2021.

RESULTS

A total of 217 members (internal physicians: 203, pediatricians: 14) responded to the questionnaire. Of these respondents, 94.0% answered that the clinical practice guidelines were referred to "always" or "often." Approximately 66.4% respondents answered that histological grade (H-Grade) derived from the "Clinical Guidelines for IgA nephropathy in Japan, 3rd version" and the "Oxford classification" were used for pathological classification. Moreover, 73.7% respondents answered that the risk grade (R-grade) derived from the "Clinical Guidelines for IgA nephropathy in Japan, 3rd version" was referred to for risk stratification. The prescription rate of renin-angiotensin system blockers increased based on urinary protein levels (> 1.0 g/day: 88.6%, 0.5-1.0 g/day: 71.0%, < 0.5 g/day: 25.0%). Similarly, the prescription rate of corticosteroids increased according to proteinuria levels (> 1.0 g/day: 77.8%, 0.5-1.0 g/day: 52.8%, < 0.5 g/day: 11.9%). The respondents emphasized on hematuria when using corticosteroids. In cases of hematuria, the indication rate for corticosteroids was higher than in those without hematuria, even if the urinary protein level was 1 g/gCr or less. Few severe infectious diseases or serious deterioration in glycemic control were reported during corticosteroid use.

CONCLUSION

Our questionnaire survey revealed real-world aspects of IgAN treatment in Japan.

An extremely energetic cosmic ray observed by a surface detector array

Cosmic rays are energetic charged particles from extraterrestrial sources, with the highest-energy events thought to come from extragalactic sources. Their arrival is infrequent, so detection requires instruments with large collecting areas. In this work, we report the detection of an extremely energetic particle recorded by the surface detector array of the Telescope Array experiment. We calculate the particle's energy as [Formula: see text] (~40 joules). Its arrival direction points back to a void in the large-scale structure of the Universe. Possible explanations include a large deflection by the foreground magnetic field, an unidentified source in the local extragalactic neighborhood, or an incomplete knowledge of particle physics.

Genomic characterization of thymic epithelial tumors in a real-world dataset

BACKGROUND

Thymic epithelial tumors (TETs) are rare neoplasms arising in the mediastinum, including thymic carcinomas and thymomas. Due to their rarity, little is known about the genomic profiles of TETs. Herein, we investigated the genomic characteristics of TETs evaluated in a large comprehensive genomic profiling database in a real-world setting.

METHODS

We included data from two different cohorts: Foundation Medicine Inc. (FMI) in the United States and the Center for Cancer Genomics and Advanced Therapeutics (C-CAT) in Japan. Samples profiled were examined for all classes of alterations in 253 genes targeted across all assays. Tumor mutational burden (TMB) and microsatellite instability (MSI) were also evaluated.

RESULTS

A total of 794 patients were collected in our study, including 722 cases from FMI and 72 cases from C-CAT. In the FMI data, CDKN2A (39.9%), TP53 (30.2%) and CDKN2B (24.6%) were frequently altered in thymic carcinoma, versus TP53 (7.8%), DNMT3A (6.8%), and CDKN2A (5.8%) in thymoma. TMB-high (≥10 mutations/Mb) and MSI were present in 7.0% and 2.3% of thymic carcinomas, and 1.6% and 0.3% of thymomas, respectively. Within C-CAT data, CDKN2A (38.5%), TP53 (36.5%) and CDKN2B (30.8%) were also frequently altered in thymic carcinoma, while alterations of TSC1, SETD2 and LTK (20.0% each) were found in thymoma.

CONCLUSIONS

To the best of our knowledge, this is the largest cohort in which genomic alterations, TMB and MSI status of TETs were investigated. Potential targets for treatment previously unbeknownst in TETs are identified in this study, entailing newfound opportunities to advance therapeutic development.

Measuring and maintaining organ perfusion in a patient with Takayasu's arteritis undergoing cardiac surgery

Takayasu's arteritis is a rare vasculitis affecting the aorta and its branches. Disease progression can result in arterial stenosis and subsequent organ dysfunction. Estimating organ perfusion by measuring the peripheral blood pressure can be challenging because it may be altered by arterial stenosis. We report the case of a 61-year-old woman with Takayasu's arteritis with aortic and mitral regurgitation who presented for aortic valve replacement and mitral valvuloplasty. Peripheral arterial pressure was considered a less reliable surrogate for organ perfusion because the patient had diminished blood flow in both the lower and upper extremities. In addition to the bilateral radial arterial pressure, the blood pressure in the ascending aorta was monitored to estimate the patient's organ perfusion pressure during cardiopulmonary bypass. The initial target blood pressure was determined based on the pre-operative baseline and modified by measurement of the aortic pressure. Cerebral oximetry using near-infrared spectroscopy and mixed venous saturation was monitored to estimate oxygen supply-demand balance, which helped evaluate cerebral perfusion and determine the transfusion threshold. The entire procedure was uneventful, and no organ dysfunction was observed postoperatively.

Safety Profile of the Concomitant Use of Atorvastatin and Cyclosporine in Renal Transplant Recipients

Cyclosporine (CyA) and atorvastatin (AT) are often administered concomitantly to treat dyslipidemia in renal transplant recipients. However, CyA greatly increases the plasma concentration of AT; therefore, concomitant use might increase the frequency of statin-induced adverse effects. The aim of this study was to investigate whether concomitant use of CyA and AT increases intolerance of the latter agent in Japanese renal transplantation recipients. We performed a retrospective cohort analysis of renal transplant recipients aged 18 years and older who had concomitantly received AT and CyA, or tacrolimus (Tac) therapy. We defined statin intolerance as a decrease in dose or discontinuation of AT due to adverse effects. We evaluated the incidence of statin intolerance in concomitant therapy with CyA for 100 days after the initial administration of AT in comparison with Tac. A total of 144 renal transplant recipients who received AT and CyA, or Tac between January 2013 and December 2019 were included. There was no statistical difference in the incidence of statin intolerance in both the CyA (1.8%; 1/57 patients) and Tac (3.4%; 3/87 patients) groups. Concomitant use of CyA and AT might not increase the incidence of statin intolerance in Japanese renal transplant recipients.

Utility of 5-aminolaevulinic acid fluorescence-guided endoscopic biopsy for malignant mesothelioma in a cat and dog

Malignant mesothelioma (MM) is uncommon in cats and dogs and can be challenging to diagnose. Adequate tissue sampling is required for superior diagnostic accuracy. Protoporphyrin IX, a metabolite of 5-aminolaevulinic acid (5-ALA), is a photosensitiser for photodynamic diagnosis (PDD). To the best of our knowledge, no study has reported the use of 5-ALA-PDD to detect MM in veterinary medicine. The present study describes the use of 5-ALA-PDD for MM diagnosis in a cat and dog, as well as the effectiveness of intracavitary chemotherapy. We evaluated the use of PDD with 5-ALA hydrochloride (5-ALA-PDD) in two cases of MM. A 12-year-old cat presented with a 1-month history of respiratory distress, and a 9-year-old dog presented with a 3-month history of mild abdominal distention. We endoscopically biopsied lesions in both the cases using 5-ALA-PDD. Histopathological examination revealed mesothelioma, and immunohistochemical staining was positive for calretinin. Both patients were treated with carboplatin. The cat died of respiratory failure. Although, the dog's condition improved 21 days after the first chemotherapeutic drug administration, the dog died on day 684 owing to cardiac-related issues. 5-ALA-PDD is thus, safe and feasible for the diagnosis of MM in veterinary medicine.

Advances in tooth agenesis and tooth regeneration

The lack of treatment options for congenital (0.1%) and partial (10%) tooth anomalies highlights the need to develop innovative strategies. Over two decades of dedicated research have led to breakthroughs in the treatment of congenital and acquired tooth loss. We revealed that by inactivating USAG-1, congenital tooth agenesis can be successfully ameliorated during early tooth development and that the inactivation promotes late-stage tooth morphogenesis in double knockout mice. Furthermore, Anti- USAG-1 antibody treatment in mice is effective in tooth regeneration and can be a breakthrough in treating tooth anomalies in humans. With approximately 0.1% of the population suffering from congenital tooth agenesis and 10% of children worldwide suffering from partial tooth loss, early diagnosis will improve outcomes and the quality of life of patients. Understanding the role of pathogenic USAG-1 variants, their interacting gene partners, and their protein functions will help develop critical biomarkers. Advances in next-generation sequencing, mass spectrometry, and imaging technologies will assist in developing companion and predictive biomarkers to help identify patients who will benefit from tooth regeneration.

Intraventricular pressure gradient: a novel colour M-mode echocardiographic-derived imaging modality to assess and predict the alterations following acute myocardial infarction

Funding Acknowledgements

Type of funding sources: None.

Background

Myocardial infarction (MI), caused by partial or total interruption of myocardial blood supply, is among the leading causes of morbidity and death. It can go silent (undetected), or it can be a catastrophic occurrence with severe hemodynamic alterations and abrupt death. Hence, immediate diagnosis or even prediction of these changes is really significant. Being the gold standard technique, echocardiography is typically adopted to identify heart dysfunctions. However, it exhibits a modest aptitude to foresee these variations. Intraventricular pressure gradient (IVPG) was introduced recently as a precise colour M-mode echocardiographic (CMME)-derived diastolic function imaging modality to assess the cardiac performance. Yet, its potential to assess and anticipate the alterations post-acute MI was not explored.

Purpose

The chief goal of this work is to study the efficacy of IVPG to measure and expect the alterations of rats’ cardiac functions at early stages of MI induced by variable LAD suture occlusion sites.

Methods

Fifty-five male SD rats were operated. Three different LAD occlusion sites were adopted to induce MI. In one group, LAD was occluded at the junction between LA and LV (MI-H, n=20). The middle and low ligation sites were more distal away from the base in two distinct groups (MI-M, n=15, and MI-L, n=10). The typical thoracotomy was accomplished in sham animals without occlusion of LAD (Sham, n=10). The sham and survived MI animals were checked using conventional echocardiography and CMME-derived IVPG on days 1, 7, 14, and 21 post MI induction. Afterwards, they were euthanized after transcatheter hemodynamics recording under the effect of anesthesia. The heart sections were stained to calculate the infarction size.

Results

The MI-H animals showed the lowest survival rate (35 % vs. 66.67, and 80 % in MI-M and MI-L groups; respectively). Moreover, they presented the most serious cardiac and hemodynamic alterations. The values of mid-to-apical, mid, and apical IVPG segments were significantly (P&lt; 0.001) declined in MI-M and MI-H groups compared to sham on days 7, 14, and 21. Likewise, they presented a meaningful reduction of the total IVPG on days 14, and 21. Contrarily, the basal IVPG was markedly (P&lt; 0.0001) elevated. Despite the echocardiographic changes were firstly recorded on day 14, the variations in the IVPG were recorded on day 7. The IVPG variables were significantly (P&lt; 0.0001) correlated with the echocardiographic, the hemodynamic (LVSP, LVDP, LVEDP, +dP/dtmax, -dP/dtmin, Tau) variables, and the infarction size. Moreover, all IVPG indices could significantly predict the cardiac and hemodynamic alterations occurred in varied degrees of severity. The Bland-Altman test confirmed the reproducibility of our IVPG measures.

Conclusion

CMME-derived IVPG is a novel and promising imaging modality with superior ability than conventional echocardiography to assess and predict the alterations encountered due to acute MI.

Transmission of foreshock waves through Earth's bow shock

The Earth's magnetosphere and its bow shock, which is formed by the interaction of the supersonic solar wind with the terrestrial magnetic field, constitute a rich natural laboratory enabling in situ investigations of universal plasma processes. Under suitable interplanetary magnetic field conditions, a foreshock with intense wave activity forms upstream of the bow shock. So-called 30 s waves, named after their typical period at Earth, are the dominant wave mode in the foreshock and play an important role in modulating the shape of the shock front and affect particle reflection at the shock. These waves are also observed inside the magnetosphere and down to the Earth's surface, but how they are transmitted through the bow shock remains unknown. By combining state-of-the-art global numerical simulations and spacecraft observations, we demonstrate that the interaction of foreshock waves with the shock generates earthward-propagating, fast-mode waves, which reach the magnetosphere. These findings give crucial insight into the interaction of waves with collisionless shocks in general and their impact on the downstream medium.

Thirty percent conversion efficiency from radiofrequency power to thrust energy in a magnetic nozzle plasma thruster

Innovations for terrestrial transportation technologies, e.g., cars, aircraft, and so on, have driven historical industries so far, and a similar breakthrough is now occurring in space owing to the successful development of electric propulsion devices such as gridded ion and Hall effect thrusters, where solar power is converted into the momentum of the propellant via acceleration of the ionized gases, resulting in a high specific impulse. A magnetic nozzle (MN) radiofrequency (rf) plasma thruster consisting of a low-pressure rf plasma source and a MN is an attractive candidate for a high-power electric propulsion device for spacecraft, as it will provide a long lifetime operation at a high-power level due to the absence of an electrode exposed to the plasma and a high thrust density. The high-density plasma produced in the source is transported along the magnetic field lines toward the open-source exit and the plasma is then spontaneously accelerated in the MN. By ejecting the plasma flow from the system, the reaction forces are exerted to the thruster structure including the source and the MN, and the spacecraft is resultantly propelled. The thruster will open the next door for space technologies, while the performance of the MN rf plasma thruster has been lower than those of the mature electric propulsion devices due to the energy loss to the physical walls. Here the thruster efficiency of about 30%, being the highest to date in this type of thruster, is successfully obtained in the MN rf plasma thruster by locating a cusp magnetic field inside the source, which acts as a virtual magnetic wall isolating the plasma from the source wall. The increase in the thrust by the cusp can be explained by considering the reductions of the loss area and the plasma volume in a thrust analysis combining a global source model and a one-dimensional MN model.

Live imaging of nitric oxide release in vascular endothelial cells in response to mechanical stimuli on an organ chip

Background

Nitric oxide (NO), released from vascular endothelial cells in response to mechanical stimuli, regulates cardiac contractility and are also involved in the prevention of the development of cardiac hypertrophy.

Purpose

To establish an experimental system for live observation of NO release in response to mechanical stimuli on an organ chip.

Methods

Organ chips, which we used for the development of a heart-on-a-chip in the previous study [1], were used.

We seeded 300,000 human umbilical vein endothelial cells on a stretchable elastic membrane coated with Matrigel of a chip channel. Shear stress was applied to the cells by increasing flow rate of a peristaltic pump connected to the chip channel (Figure 1A). Pressure stimulus was applied by hydrostatic pressure. Stretch stimulus was applied by suction to the side ports of a chip using an electric syringe pump (Figure 1B). Cells were stained with 10 μM 4,5-diaminofluorescein diacetate for fluorescent live NO imaging.

Results

Monolayers of the endothelial cells formed intercellular junctions confirmed by CD31 staining (Figure 1C, yellow). Apparent permeability, which was measured by Texas red dye (MW 3000), was maintained at a low level of ∼3x10–6 cm/s until day 30, suggested the formation of robust intercellular junction.

When the endothelial cells were subjected to a pressure stimulus of 60 mmHg for 60 s, NO release was observed that lasted for &gt;2 minutes (Figure 2A). A peak value of 1.46±1.08 (mean ± standard deviation) times the baseline was observed 271 s after the beginning of the pressure stimulus (n=251 cells). When the cells were subjected to a 1% stretch for 60 s, a peak value of 1.29±0.33 times the baseline was observed 105 s after the beginning of the stretch stimulus (Figure 2B). A shear stress of 0.01 dyn/cm2 hardly increased NO release (1.20±0.27 times the baseline, Figure 2C).

Conclusion

The system for live NO imaging in vascular endothelial cells in response to mechanical stimuli was established using organ-on-a-chip. The heart-on-a-chip with endothelial cells will be useful in elucidating the effects of mechanical stimulus such as hypertension on the contractile function and the remodeling of the heart.

Funding Acknowledgement

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

[Long-Term Prognosis of Patients with Biliary Tract Cancer Undergoing Pancreaticoduodenectomy]

We divided the patients with biliary tract cancer who underwent pancreaticoduodenectomy(PD)at our hospital into the 5-year recurrence-free and recurrence groups and investigated the prognostic factors. Additionally, we investigated the efficacy of adjuvant chemotherapy in patients with and without lymph node (LN) metastasis. There was no significant difference between the two groups for patient characteristics and perioperative factors. However, patients with LN metastasis tended to have a higher recurrence rate. For patients without LN metastasis, the median overall survival(OS)was not significantly different between the patients who received and did not receive adjuvant chemotherapy. For patients with LN metastasis, although it was not significantly different(p=0.234), the OS of patients who received adjuvant therapy was more than 3 times than that of patients who did not(58.6 months and 18.4 months, respectively). For patients with biliary tract cancer who underwent PD, positive LN metastasis may be a poor prognostic factor, and adjuvant therapy may possibly improve prognosis.