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IODP Site U1437 is located in the Izu rear‐arc region, approximately 330 km west of the Izu‐Bonin trench axis. The oldest four units (Units IV through Unit VII) include volcaniclastic sediment and in situ hyaloclastites. They have ages of about 6–15 Ma, shortly after cessation of Shikoku backarc basin opening. Three magma types are identified by their distinct geochemistry; they are similar types to those found in the modern Izu arc (Rear Arc Seamount Chain [RASC]‐type, Rift‐type, and volcanic front [VF]‐type). RASC‐type has the most enriched Nd and Hf isotope and fluid‐immobile trace element ratios and dominates from 9 to 6 Ma. Rift‐type, dominant from 15 to 9 Ma, is similar to VF‐type in Nd‐Hf isotopes but has the least radiogenic Sr and Pb, and intermediate La/Yb and Nb/Yb, indicating a more fertile mantle source and less hydrous slab component than VF‐type. Less common and randomly distributed VF‐type sediments have the most radiogenic Sr and Pb, and the highest Ba/(Th, LREE [light rare earth element]) ratios, and are interpreted to be distally derived. The genesis of mafic Unit VII samples (~15 Ma) was modeled using the Arc Basalt Simulator. Results are most similar to those for basalts in the modern rift environment indicating the addition of ~1% of a melt‐rich slab component generated at ~125 km, to a Philippine Sea Plate ambient mantle that was more depleted than DMM (depleted MORB mantle). The initial post‐Shikoku basin magmatism in the Izu rear‐arc generated Rift‐type magmas for about 6 million years before the distinctive RASC‐type magmatism began, which then became increasingly enriched. Plain Language Summary: We explore the history of magma genesis in the Izu rear‐arc, Japan, by studying the geochemistry of volcaniclastic sediments that were obtained by ocean drilling. This paper presents their Sr‐Pb‐Nd‐Hf isotope ratios and numerical models of magma genesis. We identify the presence of three geochemical types that change through time. Rift‐type formed soon after cessation of seafloor spreading in the Shikoku Basin at ~15 Ma and came from a more fertile mantle source with a less hydrous slab component than at the contemporaneous volcanic front. This type is most like basalts from rifts behind the current volcanic front and was unknown before drilling. RASC‐type dominates from 9 to 6 Ma and has more enriched Nd and Hf isotope and fluid‐immobile trace element ratios that are like those of rocks dredged from the coeval rear‐arc seamount chains. VF‐type is uncommon, randomly dispersed, and interpreted as derived from the distal volcanic front. The results confirm that the arc front has migrated trenchward since the Miocene. Key Points: The geochemistry of the volcaniclastics and hyaloclastites of IODP Site U1437 is reportedTwo magma types and one magma type of distal origin existed in the Izu rear‐arc after spreading in the Shikoku Basin endedThe initial post backarc basin magmatism generated magmas similar to Quaternary Rift‐type and evolved to rear‐arc seamount chain type [ABSTRACT FROM AUTHOR]

Volcanoes in the East Asian/Pacific region have been the source of some of the largest magnitude eruptions during the Late Quaternary, and accurately evaluating their eruptive histories is essential for hazard assessments. To overcome difficulties in resolving and precisely dating eruptions in the near‐source realm, the high‐resolution (varved) sediments of Lake Suigetsu (central Honshu, Japan) were examined for the presence of non‐visible (cryptotephra) layers from 50 ka up until the 30 ka Aira‐Tanzawa (AT) caldera‐forming event of Aira volcano. Cryptotephra layers are four times more frequently preserved than visible markers in the Suigetsu sediments, meaning that this archive provides a unique and unprecedented record of eruptions that were dispersed over the densely populated regions of central Honshu. Major and trace element volcanic glass chemistry is used to fingerprint the ash layers and pinpoint their volcanic origin. Tephras are found throughout the investigated sediments, but the highest abundance of ash fall events are recorded between 39 and 30 ka, capturing a period of intense volcanism at calderas on Kyushu Island (Japan). The augmented Suigetsu tephrostratigraphy records at least seven eruptions from Aso caldera (southern Kyushu) that post‐date the widespread ACP‐4 Plinian eruption (ca. 50 ka) and four explosive events from Aira (central Kyushu) that occurred leading up to the catastrophic caldera‐forming AT eruption (ca. 30 ka). Key Points: Refined eruption stratigraphy for Japan (between 50 and 30 ka) through the identification of cryptotephra layers in the varved Lake Suigetsu sediment coreAso caldera was particularly active between 35 and 30 ka, producing at least 5 tephras that were dispersed >500 km from sourceA large eruption occurred from Aira 1.3 ka before the cataclysmic VEI 7 caldera‐forming AT eruption that blanketed Japan in ash [ABSTRACT FROM AUTHOR]

Investigates the effect of protein kinase C isoforms on tumor necrosis factor-alpha-mediated cellular damage using a human intestinal cell line. Role in decreasing the extent of intestinal cellular viability; Factors that causes changes in cellular integrity; Impact on cellular apoptosis.

An innovative method is presented to estimate the size effect on the ferroelectric phase transitions in the barium titanate ceramic system. The method is based on the phenomenological thermodynamic theory with additional stress led by surface bond contraction. Two symmetry-breaking factors are introduced to correct the stress. This method has enabled us to predict the changing trends in phase transitions and the critical grain size for the disappearance of ferroelectric phase, which is beyond the prediction of existing models. [ABSTRACT FROM AUTHOR]

Background: Patients undergoing surgical anesthesia increasingly suffer from preoperative depression. Clinical studies have shown that depression is a risk factor for perioperative neurocognitive disorders (PNDs) in elder patients. However, the underlying mechanism, especially at the neural circuit level, remains poorly understood., Methods: Right carotid artery separation under sevoflurane and chronic social defeat stress (CSDS) in adult mice were used to establish surgical anesthesia and chronic depression models. Cognitive function was assessed by the Y maze and novel object recognition tests. A chemogenetic approach was used to modulate the locus coeruleus-dorsal hippocampal CA1 (LC-dCA1) circuit. Hippocampal synaptic alterations were evaluated by Golgi staining and whole-cell patch clamp recording., Results: We found that CSDS induced synaptic impairments in dorsal hippocampal CA1 pyramidal neurons and cognitive deficits in adult mice after surgery under sevoflurane. Chemogenetic activation of the LC-dCA1 pathway significantly alleviated the CSDS-induced synaptic impairments and cognitive dysfunction. On the contrary, inhibition of this pathway could mimic CSDS-induced deficits. Furthermore, we showed that dopamine played an important role in CSDS-induced PNDs in adult mice after surgery/sevoflurane., Conclusion: Overall, our results have demonstrated a vital role for the LC-dCA1 pathway in CSDS-induced PNDs in adult mice undergoing surgery with sevoflurane anesthesia., (© 2023 The Authors. CNS Neuroscience & Therapeutics published by John Wiley & Sons Ltd.)

We aimed to study the effects and underlying mechanism of different intensities of continuous training (CT) on vascular inflammation and oxidative stress in spontaneously hypertensive rats (SHR). Rats were divided into five groups (n = 12): Wistar-Kyoto rats sedentary group (WKY-S), sedentary group (SHR-S), low-intensity CT group (SHR-L), medium-intensity CT group (SHR-M) and high-intensity CT group (SHR-H). Changes in body mass, heart rate and blood pressure were recorded. The rats were euthanized after 14 weeks, and blood and vascular tissue samples were collected. Haematoxylin and Eosin staining was used to observe the aortic morphology, and Western blot was used to detect the expression of mesenteric artery proteins. After CT, the mean arterial pressures improved in SHR-L and SHR-M and increased in SHR-H compared with those in SHR-S. Vascular inflammation and oxidative stress levels significantly subsided in SHR-L and SHR-M (p < 0.05), whereas in SHR-H, only vascular inflammation significantly subsided (p < 0.05), and oxidative stress remained unchanged (p > 0.05). AMPK and SIRT1/3 expressions in SHR-L and SHR-M were significantly up-regulated than those in SHR-S (p < 0.05). These results indicated that low- and medium-intensity CT can effectively reduce the inflammatory response and oxidative stress of SHR vascular tissue, and high-intensity CT can improve vascular tissue inflammation but not oxidative stress., (© 2021 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Purpose: To provides the clinical and genetic characteristics of a series of Chinese patients with X-linked juvenile retinoschisis (XLRS) through multimodal imaging and next-generation sequencing., Methods: Thirty patients (60 eyes) from 29 unrelated families of Chinese origin with XLRS were screened using multigene panel testing, and underwent a complete clinical evaluation. All variants identified in this study and reported in the Human Gene Mutation Database were analysed., Results: Twenty-five distinct variants in the retinoschisin gene were identified, of which eight were novel, and one was de novo. Missense mutations were the most prevalent type, and mutation hot spot was localized in the discoidin domain. The mean Snellen best-corrected visual acuity was 0.28 ± 0.17. Of all eyes presenting with schisis, 92.86% had lamellar schisis and 62.5% had peripheral schisis. Schisis changes mostly involved inner and outer nuclear layers. X-linked juvenile retinoschisis (XLRS) patients had a high incidence of complications, and peripheral schisis was a risk factor for it. No obvious genotype-phenotype association was observed., Conclusion: This study provides comprehensive analyses of the genetic and clinical characteristics of XLRS in a cohort of Chinese patients. The fourth de novo mutation in RS1 was identified. And we show that XLRS has a wide spectrum of clinical characteristics; hence, molecular diagnosis is crucial for its diagnosis, differential diagnosis and genetic counselling. Peripheral schisis is a risk factor for the high incidence of complications, and no clear genotype-phenotype correlations were found., (© 2020 The Authors. Annals of Clinical and Translational Neurology published by Wiley Periodicals LLC on behalf of American Neurological Association.)

Purpose: To explore an early, rapid and precise diagnosis of Stickler syndrome type I (STL1) and to enrich the spectrum of COL2A1 mutations in the Chinese population, which is poorly studied at present., Methods: In the current study, we analysed 115 patients with high myopia by next-generation sequencing and identified five STL1 patients from four unrelated Chinese families. The clinical features of all patients were reviewed in detail., Results: Four variants of COL2A1 were identified, including two novel variants (c.1435delG and c.184delG) and two previously reported variants (c.1221+1G>A and c.1030C>T). Three variants caused premature termination codons which were common in STL1. In addition, we proposed a new diagnostic tactic to improve early diagnostics of STL1 in patients., Conclusion: In this study, our findings expanded the spectrum of COL2A1 mutations with two novel variants and provided a new diagnostic tactic for reference, which was of great significance. Precise diagnosis on the basis of clinical manifestations and genetic testing will become the gold standard to diagnose inherited ocular disorders or syndromes in the future., (© 2019 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)

Environment has a potential effect on the animal symbiotic microbiome. Here, to study the potential relationship of the symbiotic microbiomes of wild amphibians with altitude, we collected the gut and skin samples from frogs (nine species) and the environmental samples (water and soil samples) from the Leshan Mountains (altitude: 360-410 m) and Gongga Mountains (altitude: 3340-3989 m) on the eastern edge of the Tibetan Plateau. Bufo gargarizans (Bg) samples were collected from both the Leshan and Gongga mountain regions (Bg was the only species sampled on both mountains). The DNA extracted from each sample was performed high-throughput sequencing (MiSeq) of bacterial 16S rRNA gene amplicons. High relative abundance of Caulobacteraceae and Sphingomonadaceae was found in skin samples from both Bg and the other high-altitude amphibians (nine species combined). High relative abundance of Coxiellaceae and Mycoplasmataceae was found in gut samples from both Bg and the other high-altitude amphibians. Furthermore, the alpha and beta diversities of skin and gut samples from Bg and the other amphibian species (nine species combined) were similar. In terms of the symbiotic microbial community, the low-altitude samples were less diverse and more similar to each other than the high-altitude samples were. We speculated that extreme high-altitude environments and host phylogeny may affect the amphibian microbiome. Despite the distinct microbial community differences between the skin and gut microbiomes, some functions were similar in the Bg and combined high-altitude samples. The Bg and high-altitude skin samples had higher oxidative stress tolerance and biofilm formation than the low-altitude skin samples. However, the opposite results were observed for the Bg and high-altitude gut samples. Further study is required to determine whether these characteristics favor high-altitude amphibian adaptation to extreme environments., (© 2020 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.)

The composition of the intestinal microbial community may vary across developmental stages. In this study, we explored how this microbial community shifted along the intestinal tract of the Chinese giant salamander (Andrias davidianus) at various ages. Next-generation sequencing was used to sequence the bacterial 16S rRNA gene from different kind of samples, including the stomach, duodenum, ileum, and rectum. The highest mean relative abundance of the bacterial community in the gastrointestinal tract shifted in relation to age: within the first year, Bacteroidetes (47.76%) dominated the gut microbiome, whereas Proteobacteria was the most dominant at age 2 (32.88%) and age 3 (30.78%), and finally, Firmicutes was the most dominant at age 4 (34.70%). The overall richness of the gut bacterial community also generally increased from age 2 to 4. Hierarchical cluster analysis revealed that the gut microbiome at age 2 had greater variability than that at either age 3 or 4, likely representing a shift in diet from yolk or redworms as a juvenile to shrimp or crab as an adult. As these salamanders develop, their gastrointestinal tracts increase in complexity, and this compartmentalization may also facilitate an increase in microbial gut diversity., (© 2018 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.)

Excessive production of reactive oxygen species (ROS) and P2X7R activation induced by high glucose increases NLRP3 inflammasome activation, which contributes to the pathogenesis of diabetic cardiomyopathy. Although H3 relaxin has been shown to inhibit cardiac fibrosis induced by isoproterenol, the mechanism has not been well studied. Here, we demonstrated that high glucose (HG) induced the collagen synthesis by activation of the NLRP3 inflammasome, leading to caspase-1 activation, interleukin-1β (IL-1β) and IL-18 secretion in neonatal rat cardiac fibroblasts. Moreover, we used a high-glucose model with neonatal rat cardiac fibroblasts and showed that the activation of ROS and P2X7R was augmented and that ROS- and P2X7R-mediated NLRP3 inflammasome activation was critical for the collagen synthesis. Inhibition of ROS and P2X7R decreased NLRP3 inflammasome-mediated collagen synthesis, similar to the effects of H3 relaxin. Furthermore, H3 relaxin reduced the collagen synthesis via ROS- and P2X7R-mediated NLRP3 inflammasome activation in response to HG. These results provide a mechanism by which H3 relaxin alleviates NLRP3 inflammasome-mediated collagen synthesis through the inhibition of ROS and P2X7R under HG conditions and suggest that H3 relaxin represents a potential drug for alleviating cardiac fibrosis in diabetic cardiomyopathy., (© 2018 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.)