Impact of an unprecedented marine heatwave on extremely hot summer over Northern Japan in 2023.

Possible local influence of an extreme marine heatwave is investigated on unprecedentedly hot summer around northern Japan in 2023. Sea-surface temperatures (SSTs) and subsurface ocean temperatures around northern Japan were also unprecedentedly high in the summer. This was especially the case off the east coast of Japan, where cool Oyashio water was replaced with much warmer water due to a striking poleward meander of the Kuroshio Extension persistent from the spring. Particularly amplified near-surface air temperature anomalies and even stronger warm anomalies in the subsurface ocean suggest that the marine heatwave acted to sustain the atmospheric heatwave. Anomalous upward of latent and sensible heat fluxes from the warmed sea surface are indicative of local oceanic impact. The warm SST anomalies reduced the lower-tropospheric stratification to maintain unfavourable condition for low-level cloud formation, which in turn led to increased surface insolation for further SST warming as positive feedback. The increased moisture in the warmed lower troposphere contributed to the enhanced surface downward longwave radiation. This enhanced greenhouse effect acted not only as positive feedback on the warm SST anomalies that increased evaporation but also as a contributor for the extreme warmth over northern Japan landmass.

Bone morphogenetic protein signaling inhibitor improves differentiation and function of 3D muscle construct fabricated using C2C12.

Functional tissue-engineered artificial skeletal muscle tissue has great potential for pharmacological and academic applications. This study demonstrates an in vitro tissue engineering system to construct functional artificial skeletal muscle tissues using self-organization and signal inhibitors. To induce efficient self-organization, we optimized the substrate stiffness and extracellular matrix (ECM) coatings. We modified the tissue morphology to be ring-shaped under optimized self-organization conditions. A bone morphogenetic protein (BMP) inhibitor was added to improve overall myogenic differentiation. This supplementation enhanced the myogenic differentiation ratio and myotube hypertrophy in two-dimensional cell cultures. Finally, we found that myotube hypertrophy was enhanced by a combination of self-organization with ring-shaped tissue and a BMP inhibitor. BMP inhibitor treatment significantly improved myogenic marker expression and contractile force generation in the self-organized tissue. These observations indicated that this procedure may provide a novel and functional artificial skeletal muscle for pharmacological studies.

Characterization of rice endosperm-derived antidepressant-like peptide (REAP): An orally active novel tridecapeptide derived from rice protein.

It is ideal to ingest bioactive substances from daily foods to stay healthy. Rice is the staple food for almost half of the human population. We found that an orally administered enzymatic digest of rice endosperm protein exhibits antidepressant-like effects in the tail suspension test (TST) using mice. A comprehensive peptide analysis of the digest using liquid chromatography-tandem mass spectrometry was performed, and a tridecapeptide QQFLPEGQSQSQK, detected in the digest, was chemosynthesized. Oral administration of the tridecapeptide exhibited antidepressant-like effects at a low dose comparable to classical antidepressant in the TST. This also exhibited anti-depressant-like effect in the forced swim test. We named it rice endosperm-derived antidepressant-like peptide (REAP). Intriguingly, intraperitoneal administration had no effect. Orally administered REAP(8-13) but not REAP(1-7) exhibited antidepressant-like activity, suggesting that the C-terminal structure is important for the antidepressant-like effect. We confirmed the presence of REAP, corresponding to rice glutelin type B4(130-142) and B5(130-142), in the digest. The effects of REAP were blocked by both dopamine D1 and D2 antagonists. These results suggest that it exerts its antidepressant-like activity through activation of the dopamine system. Taken together, oral administration of a novel tridecapeptide exhibited antidepressant-like effects via the dopamine system. This is the first report of a rice-derived peptide that exhibits antidepressant-like effects.

Impact of the US Accelerated Approval for New Anticancer Drugs on Time to Verification of Benefit and Regulatory Approval in the EU and Japan.

The accelerated approval (AA) program in the USA has succeeded in expediting the regulatory approval of new cancer drugs based on surrogate endpoint data. It is unclear whether the AA program promotes overall drug development, including verification of the clinical benefit, as the verification of drugs granted AA often takes long time. To determine the impact of the AA program on overall drug development, the time required for verification of clinical benefits was compared between anticancer drugs that initially received AA and those that received regular approval (RA). It was found that anticancer drugs that were approved under the AA program took longer time for verification, suggesting that the program may delay the start of a confirmatory study, and there may be room for speeding up the process. In addition, discordance was found in the pivotal study between the USA and the EU and the USA and Japan for obtaining the indication for which AA was granted in the USA and a delay in the start of the confirmatory study for the AA indication was considered to lead to a delay in approval in the EU and Japan. Early initiation of confirmatory studies for AA indications is recommended to reduce the time that patients receive drugs with unproven benefit in the USA, as well as to deliver innovative new drugs to patients earlier in the EU and Japan.

Akaluc/AkaLumine bioluminescence system enables highly sensitive, non-invasive and temporal monitoring of gene expression in Drosophila.

Bioluminescence generated by luciferase and luciferin has been extensively used in biological research. However, detecting signals from deep tissues in vivo poses a challenge to traditional methods. To overcome this, the Akaluc and AkaLumine bioluminescent systems were developed, resulting in improved signal detection. We evaluate the potential of Akaluc/AkaLumine in Drosophila melanogaster to establish a highly sensitive, non-invasive, and temporal detection method for gene expression. Our results show that oral administration of AkaLumine to flies expressing Akaluc provided a higher luminescence signal than Luc/D-luciferin, with no observed harmful effects on flies. The Akaluc/AkaLumine system allows for monitoring of dynamic temporal changes in gene expression. Additionally, using the Akaluc fusion gene allows for mRNA splicing monitoring. Our findings indicate that the Akaluc/AkaLumine system is a powerful bioluminescence tool for analyzing gene expression in deep tissues and small numbers of cells in Drosophila.

Optogenetic stimulation of vagal nerves for enhanced glucose-stimulated insulin secretion and ß cell proliferation.

The enhancement of insulin secretion and of the proliferation of pancreatic ß cells are promising therapeutic options for diabetes. Signals from the vagal nerve regulate both processes, yet the effectiveness of stimulating the nerve is unclear, owing to a lack of techniques for doing it so selectively and prolongedly. Here we report two optogenetic methods for vagal-nerve stimulation that led to enhanced glucose-stimulated insulin secretion and to ß cell proliferation in mice expressing choline acetyltransferase-channelrhodopsin 2. One method involves subdiaphragmatic implantation of an optical fibre for the photostimulation of cholinergic neurons expressing a blue-light-sensitive opsin. The other method, which suppressed streptozotocin-induced hyperglycaemia in the mice, involves the selective activation of vagal fibres by placing blue-light-emitting lanthanide microparticles in the pancreatic ducts of opsin-expressing mice, followed by near-infrared illumination. The two methods show that signals from the vagal nerve, especially from nerve fibres innervating the pancreas, are sufficient to regulate insulin secretion and ß cell proliferation.

Analysis of Molecular Changes and Features in Rat Knee Osteoarthritis Cartilage: Progress From Cellular Changes to Structural Damage.

OBJECTIVE: Although knee osteoarthritis (KOA) is a common disease, there is a lack of specific prevention and early treatment methods. Hence, this study aimed to examine the molecular changes occurring at different stages of KOA to elucidate the dynamic nature of the disease. DESIGN: Using a low-force compression model and analyzing RNA sequencing data, we identified molecular changes in the transcriptome of knee joint cartilage, including gene expression and molecular pathways, between the cellular changes and structural damage stages of KOA progression. In addition, we validated hub genes using an external dataset. RESULTS: Gene set enrichment analysis (GSEA) identified the following pathways to be associated with KOA: "B-cell receptor signaling pathway," "cytokine-cytokine receptor interaction," and "hematopoietic cell lineage." Expression analysis revealed 585 differentially expressed genes, with 579 downregulated and 6 upregulated genes. Enrichment and clustering analyses revealed that the main molecular clusters were involved in cell cycle regulation and immune responses. Furthermore, the hub genes Csf1r, Cxcr4, Cxcl12, and Ptprc were related to immune responses. CONCLUSIONS: Our study provides insights into the dynamic nature of early-stage KOA and offers valuable information to support the development of effective intervention strategies to prevent the irreversible damage associated with KOA, thereby addressing a major clinical challenge.

Expansion of human mesenchymal stem cells on poly(vinyl alcohol) microcarriers.

Microcarriers provide a high surface-area-to-volume ratio that can realize high yields of cell products, including human mesenchymal stem cells (hMSCs). Here, we report a novel poly(vinyl alcohol) (PVA)-based microcarrier for hMSC expansion in suspension culture. PVA microcarriers were prepared as collagen-coated PVA hydrogels 181 µm in size and a high surface-area-to-weight ratio of 2945 cm2/g. The PVA microcarriers supported a 2.6-fold expansion of hMSCs in a 30-mL single-use stirred bioreactor after a 7 d culture period, comparable to that of commercially available microcarriers. Interestingly, we observed that hMSCs on PVA microcarriers adhered to adjacent microcarriers, resulting in the aggregation of hMSC-PVA microcarriers. Therefore, we conducted a long-term expansion culture using a bead-to-bead cell transfer method with PVA microcarriers. Fresh microcarriers were added to the cell-populated microcarriers in the bioreactor on days 7 and 14. hMSCs on PVA microcarriers continued to grow for 21 d using the bead-to-bead cell transfer method. Furthermore, magnetic PVA (PVA-mag) microcarriers were developed by loading magnetic nanoparticles into PVA microcarriers, and we demonstrated that these PVA-mag microcarriers enabled cell recovery by magnetic separation. These results suggest that these PVA microcarriers can contribute to the large-scale culture of hMSCs for regenerative medicine and cell therapy.

Development of a novel model for intraarticular adhesion in rat knee joint.

In this study, a novel rat model of knee joint adhesion was developed, and its formation was analyzed quantitatively over time. Thirty-nine Wistar rats were randomly divided into intact control (n = 3) and experimental (n = 36) groups. The latter was equally divided into three groups according to the experimental intervention: fixed with deep bending of the knee joint (group I), fixed after incision of the capsule (group II), and fixed after exposure of the patellofemoral joint to artificial patellar subluxation (group III). All rats were subdivided according to their joint immobilization period (1, 2, or 4 weeks). Thereafter, the limited range of motion of the knee joint with (limited knee range of motion) and without (limited knee joint intrinsic range of motion) skin and muscles were measured. The lengths of adhesions of the anterior knee joint and posterior capsules were evaluated histologically. The limited intrinsic range of motion of the knee joint was found to be increased in groups II and III compared to that in group I 4 weeks after immobilization. Adhesions were confirmed within 1 week after immobilization in groups II and III. The length of the adhesions in group III was significantly longer than in other groups at 2 weeks and remained longer than in group I at 4 weeks. This model may contribute to the assessment of the adhesion process and development of new therapeutic avenues following trauma or surgical invasion.

Injury data collection and utilisation practices in university sports teams: A cross-sectional study.

OBJECTIVES: This study aimed to examine injury surveillance practices in a variety of university sports teams and barriers and facilitators for injury data collection and utilisation. DESIGN: Cross-sectional study. SETTING: University sports teams in Japan. PARTICIPANTS: Medical, coaching, and other staff (non-medical/-coaching staff) of the university sports teams in Japan. MAIN OUTCOME MEASURES: The survey included 31 questions that examined the barriers and facilitators for injury data collection, and the type of data on injury and exposure collected. RESULTS: Injury data were collected during matches for 69 teams (48.3%) and training for 61 teams (42.7%). Injuries were primarily captured by athletic trainers in teams with medical staff, coaching staff and athletes in teams without medical staff. Common barriers in collecting and utilising injury data included limited funding for trained personnel and lack of time for medical staff to record data. Facilitating factors included clarification of the methods employed in recording and utilising injury data for teams with medical staff and the deployment of trained personnel to record injuries for teams without medical staff. CONCLUSIONS: Approximately half of the Japanese university teams collected injury data. Considering barriers and facilitators is crucial to facilitate the collection and utilisation of injury data.

Transplantable cell-encapsulation device using a semipermeable ethylene-vinyl alcohol copolymer membrane in a mouse diabetic model.

Cell-based therapy is an attractive approach, and encapsulation of therapeutic cells is a promising strategy because it prevents immune responses and allows transplanted cells to be retrieved in case of dysfunction. Bioartificial pancreas, in which insulin-secreting cells are encapsulated in a semipermeable membrane bag, is a new class of medical device for treating type-I diabetes. In this study, we developed a macroencapsulation device in which the pancreatic beta cell line MIN6 was encapsulated in a semipermeable bag made of an ethylene-vinyl alcohol copolymer membrane. In vitro evaluation of ATP and insulin levels revealed that MIN6 cells grown in Matrigel within the device secreted insulin in response to glucose levels. Transplantation of the device lowered blood glucose levels for 30 days in diabetic mice. Histological observation revealed that MIN6 cells formed spheroids in Matrigel, and no host cells were detected within the device. Blood levels of inflammatory cytokines in the transplanted mice were similar to those in non-transplanted mice, and antibody levels in the device were lower than those in the intraperitoneal fluid. These results suggest that the semipermeable ethylene-vinyl alcohol copolymer membrane developed in this study is useful for cell encapsulation in cell-based therapies, including beta-cell macroencapsulation for type-1 diabetes.

The Effect of the Rice Endosperm Protein Hydrolysate on the Subjective Negative Mood Status in Healthy Humans: A Randomized, Double-Blind, and Placebo-Controlled Clinical Trial.

The rice endosperm protein (REP) hydrolysate containing the following rice endosperm protein derived oligopeptides QQFLPEGQSQSQK, LPEGQSQSQK, and pEQFLPEGQSQSQK (a N-terminal pyroglutamate residue-modified peptide) reportedly showed an antidepressant-like effect in an animal model. We investigated the effect of the REP hydrolysate on healthy humans who self-reported mental fatigue with subjectively low vigor. Seventy-six participants (age: 20-64 years) were randomly allocated to two groups. The influence of the REP hydrolysate on the mood state was evaluated in two studies: single intake (Study 1) and repeated intake over 4 weeks (Study 2). A salivary stress marker, Chromogranin A (CgA), was measured in Study 1. The single intake of the REP hydrolysate significantly improved the Profile of Mood Status 2nd edition for adults (POMS 2) subscale of Tension-Anxiety. Additionally, the salivary CgA concentrations were remarkably reduced after the single intake of the REP hydrolysate. Though a single intake of the REP hydrolysate did not significantly influence the other subscales and the TMD of the POMS 2 and the Euthymia Scale, both the subjective and objective results supported the possible effect of the REP hydrolysate on reducing anxiety and nervousness. No significant positive effects on the subjective mood state (Euthymia Scale and POMS 2) and sleep quality (Insomnia Severity Index) were observed in the trial setting employed for Study 2. In conclusion, a single intake of REP hydrolysate might help relax the subjective feelings of tension and anxiety. The effectiveness of repeated REP hydrolysate intake needs to be tested in a different clinical setting.

Nanowarming of vitrified pancreatic islets as a cryopreservation technology for transplantation.

Biobanking of pancreatic islets for transplantation could solve the shortage of donors, and cryopreservation of vitrified islets is a possible approach. However, a technological barrier is rewarming of large volumes both uniformly and rapidly to prevent ice formation due to devitrification. Here, we describe successful recovery of islets from the vitrified state using a volumetric rewarming technology called "nanowarming," which is inductive heating of magnetic nanoparticles under an alternating magnetic field. Convective warming using a 37°C water bath as the gold standard for rewarming of vitrified samples resulted in a decrease in the viability of mouse islets in large volumes (>1 ml) owing to devitrification caused by slow warming. Nanowarming showed uniform and rapid rewarming of vitrified islets in large volumes. The viability of nanowarmed islets was significantly improved and islets transplanted into streptozotocin-induced diabetic mice successfully lowered serum glucose. The results suggest that nanowarming will lead to a breakthrough in biobanking of islets for transplantation.

Effectiveness and safety of Tolvaptan in infants with congenital heart disease.

BACKGROUND: Tolvaptan (TLV) is a selective vasopressin receptor 2 antagonist administered for congestive heart failure (CHF) after inadequate response to other diuretics. The effectiveness and safety of TLV have been evaluated well in adult patients. However, reports on its use in pediatric patients, especially infants, are scarce. METHODS: We retrospectively evaluated 41 children younger than 1 year of age who received TLV for CHF for congenital heart disease (CHD) between January 2010 and August 2021. We monitored the occurrence of adverse events, including acute kidney injury and hypernatremia, as well as laboratory data trends. RESULTS: Of the 41 infants included, 51.2% were male. The median age when TLV was initiated was 2 months, interquartile range (IQR) 1-4 months, and all infants had been administered other diuretics previously. The median dose of TLV was 0.1 mg/kg/day (IQR, 0.1-0.1). Urine output increased significantly after 48 h of treatment: baseline, 315 mL/day (IQR, 243-394); 48 h, 381 mL/day (IQR, 262-518) , p = 0.0004; 72 h, 385 mL/day (IQR, 301-569), p = 0.0013; 96 h, 425 mL/day (IQR, 272-524), p = 0.0006; and 144 h, 396 mL/day (IQR, 305-477), p = 0.0036. No adverse events were observed. CONCLUSIONS: Tolvaptan can be used safely and efficiently in infants with CHD. From the perspective of adverse effects, initiating administration at a lower dosage is preferable because this was found to be sufficiently effective.

Ultrasound therapy for a week promotes regeneration and reduces pro-inflammatory macrophages in a rat sciatic nerve autograft model.

Peripheral nerve injury causes long-term motor dysfunction. Ultrasound (US) therapy is expected to accelerate peripheral nerve regeneration. However, its optimal usage and effects on macrophage phenotypes during peripheral nerve regeneration remain unknown. In this study, we investigated the optimal duration of US therapy and its effects on macrophage phenotype. Twenty-seven rats with autologous sciatic nerve grafting were divided into three groups: two received US therapy (1 MHz frequency, intensity of 140 mW/cm2, 20% duty cycle, 5 min/day) for one (US1) or 4 weeks (US4), and one group received sham stimulation. Immunohistochemistry was performed 3 and 7 days after injury in another set of 12 rats. Eight weeks after the injury, the compound muscle action potential amplitude of the gastrocnemius in the US1 and US4 groups was significantly higher than that in the sham group. The toe-spreading test showed functional recovery, whereas the gait pattern during treadmill walking did not recover. There were no significant differences in motor function, histomorphometry, or muscle weight between groups. Immunohistochemistry showed that US therapy decreased the number of pro-inflammatory macrophages seven days after injury. Therefore, US therapy for both one or 4 weeks can similarly promote reinnervation and reduce proinflammatory macrophages in autograft model rats.

Effective magnetic hyperthermia induced by mitochondria-targeted nanoparticles modified with triphenylphosphonium-containing phospholipid polymers.

Magnetic hyperthermia (MHT) is a promising cancer treatment because tumor tissue can be specifically damaged by utilizing the heat generated by nano-heaters such as magnetite nanoparticles (MNPs) under an alternating magnetic field. MNPs are taken up by cancer cells, enabling intracellular MHT. Subcellular localization of MNPs can affect the efficiency of intracellular MHT. In this study, we attempted to improve the therapeutic efficacy of MHT by using mitochondria-targeting MNPs. Mitochondria-targeting MNPs were prepared by the modification of carboxyl phospholipid polymers containing triphenylphosphonium (TPP) moieties that accumulate in mitochondria. The mitochondrial localization of polymer-modified MNPs was supported by transmission electron microscopy observations of murine colon cancer CT26 cells treated with polymer-modified MNPs. In vitro and in vivo MHT using polymer-modified MNPs revealed that the therapeutic effects were enhanced by introducing TPP. Our results indicate the validity of mitochondria targeting in enhancing the therapeutic outcome of MHT. These findings will pave the way for developing a new strategy for the surface design of MNPs and therapeutic strategies for MHT.

The Efficacy of Drug-Coated Balloon for Acute Coronary Syndrome.

Background: Percutaneous coronary intervention using a drug-eluting stent (DES) is a common therapeutic option for acute coronary syndrome (ACS). However, stent-associated complications, such as bleeding associated with dual antiplatelet therapy, in-stent restenosis, stent thrombosis, and neoatherosclerosis, remain. Drug-coated balloons (DCBs) are expected to reduce stent-associated complications. This study aimed to assess the efficacy of DCB therapy and compare it with that of DES therapy in patients with ACS. Materials and Methods: In this single-center, retrospective, observational study, we examined all patients with ACS treated with DCB or DES between July 2014 and November 2020. Patients with left main trunk lesions were excluded. The primary outcome was a composite of major adverse cardiovascular events (MACE: cardiac death, myocardial infarction, and target lesion revascularization) at one year. Results: Three hundred and seventy-two patients were treated with DES, and 83 patients were treated with DCB. MACE occurred in 10 (12.0%) patients in the DCB group and in 50 (13.4%) patients in the DES group (P=0.73). Conclusions: DCB is a valuable and effective therapy for patients with ACS. Moreover, DCB may become an alternative therapy for DES in patients with ACS.

Molecular profiling of the stroke-induced alterations in the cerebral microvasculature reveals promising therapeutic candidates.

Stroke-induced cerebral microvascular dysfunction contributes to aggravation of neuronal injury and compromises the efficacy of current reperfusion therapies. Understanding the molecular alterations in cerebral microvessels in stroke will provide original opportunities for scientific investigation of novel therapeutic strategies. Toward this goal, using a recently optimized method which minimizes cell activation and preserves endothelial cell interactions and RNA integrity, we conducted a genome-wide transcriptomic analysis of cerebral microvessels in a mouse model of stroke and compared these transcriptomic alterations with the ones observed in human, nonfatal, brain stroke lesions. Results from these unbiased comparative analyses have revealed the common alterations in mouse stroke microvessels and human stroke lesions and identified shared molecular features associated with vascular disease (e.g., Serpine1/Plasminogen Activator Inhibitor-1, Hemoxygenase-1), endothelial activation (e.g., Angiopoietin-2), and alterations in sphingolipid metabolism and signaling (e.g., Sphigosine-1-Phosphate Receptor 2). Sphingolipid profiling of mouse cerebral microvessels validated the transcript data and revealed the enrichment of sphingomyelin and sphingoid species in the cerebral microvasculature compared to brain and the stroke-induced increase in ceramide species. In summary, our study has identified novel molecular alterations in several microvessel-enriched, translationally relevant, and druggable targets, which are potent modulators of endothelial function. Our comparative analyses have revealed the presence of molecular features associated with cerebral microvascular dysfunction in human chronic stroke lesions. The results shared here provide a detailed resource for therapeutic discovery of candidates for neurovascular protection in stroke and potentially, other pathologies exhibiting cerebral microvascular dysfunction.