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Purpose: Reduced capillary number in skeletal muscle due to disuse can hinder the delivery of insulin and amino acid delivery to muscle cells, diminishing insulin activity and muscle protein synthesis, ultimately contributing to anabolic resistance. However, it remains unknown whether mitigating capillary regression during inactivity improves anabolic resistance. This study aimed to investigate the effect of increasing capillary number through the administration of prazosin, which can increase blood flow and prevent capillary regression, on anabolic resistance in skeletal muscle induced by disuse., Methods: Male Sprague Dawley rats were divided into control and hindlimb unloading (HU) groups, with half of each group receiving prazosin (50 mg/L) in their drinking water for 2 weeks. Histological analysis of the soleus muscles was conducted to measure the capillary-to-fiber (C/F) ratio, while western blotting was performed to measure the activation of the Akt/mTORC1 muscle protein synthesis pathway before and after insulin stimulation., Results: The C/F ratios were significantly lower in the HU and HU + Prz groups than in the control group but were significantly higher in the HU + Prz group than in the HU group. Following insulin stimulation, the phosphorylation levels of Akt, p70S6K, and S6RP increased in all groups, with a significantly greater increase observed in the HU + Prz group compared to the HU group, indicating improved molecular signaling related to muscle protein synthesis., Conclusion: Administration of prazosin during hindlimb unloading mitigated capillary regression and enhanced insulin-stimulated muscle protein synthesis response. These findings suggest that enhancing capillary number may reduce the anabolic resistance caused by muscle disuse., Supplementary Information: The online version contains supplementary material available at 10.1007/s40200-024-01454-y., Competing Interests: Disclosure of conflicts of interestThe authors declared that they have no conflict of interest., (© The Author(s), under exclusive licence to Tehran University of Medical Sciences 2024. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Perovskite oxyhydrides have attracted recent attention due to their intriguing properties such as ionic conductivity and catalysis, but their repertoire is still restricted compared to perovskite oxynitrides and oxyfluorides. Historically, perovskite oxyhydrides have been prepared mostly by topochemical reactions and high-pressure (HP) reactions, while in this study, we employed a mechanochemical (MC) approach, which enables the synthesis of a series of AB O 2 H-type oxyhydrides, including those with the tolerance factor ( t ) much smaller than 1 (e.g., SrScO 2 H with t = 0.936) which cannot be obtained by HP synthesis. The octahedral tilting, often present in perovskite oxides, does not occur, suggesting that the lack of π-symmetry of the H 1s orbital and the large polarization destabilize tilted low-symmetry structures. Interestingly, SrCrO 2 H ( t = 0.997), previously reported with the HP method, was not achieved with the MC method. A comparative analysis revealed a correlation between the feasibility of MC reactions and the (calculated) shear modulus of the starting reagents (binary oxides and hydrides). Notably, this indicator is not exclusive to oxyhydride perovskites but extends to oxide perovskites (Sr M O 3 ). This study demonstrates that MC synthesis offers unique opportunities not only to expand the compositional space in oxyhydrides in various structural types but also to provide a guide for the choice of starting materials for the synthesis of other compounds.

The external urethral sphincter (EUS) is crucial in urinary continence development. Understanding the morphological features of the EUS in female rats after vaginal distention (VD), using a model of birth trauma, would aid in evaluating its functional and metabolic properties. Our recent study demonstrated that the EUS in female rats expresses one slow (type 1) and two fast (types 2A and 2B) myosin heavy chain (MHC) isoforms. Our preliminary experiment revealed that type 2B isoform expression was markedly reduced in the EUS 4 weeks after VD. Here, we aimed to examine the expression patterns of these three types of MHC isoforms, and an embryonic MHC, a marker of regeneration fibers, in the EUS of rats 3 days and 1, 2, and 8 weeks after VD using immunofluorescence staining. Hence, type 2B fibers were selectively damaged early in post-VD and did not recover fully later. Muscle regeneration in the sphincter peaked 1 week after trauma using a marker of immature fibers, embryonic myosin heavy chain. Electron microscopy revealed that the EUS of female rats was composed of mitochondria-rich muscle fibers. Myoblasts or immature muscle fibers were discovered in the sphincter layer 1 week after trauma. These results suggest that myogenesis after VD may not contribute to restoring normal fiber composition in a female rat's EUS., (© 2023 American Association for Anatomy.)

Typically, transition metals are considered as the centers for the activation of dinitrogen. Here we demonstrate that the nitride hydride compound Ca 3 CrN 3 H, with robust ammonia synthesis activity, can activate dinitrogen through active sites where calcium provides the primary coordination environment. DFT calculations also reveal that an associative mechanism is favorable, distinct from the dissociative mechanism found in traditional Ru or Fe catalysts. This work shows the potential of alkaline earth metal hydride catalysts and other related 1 D hydride/electrides for ammonia synthesis., (© 2023 Wiley-VCH GmbH.)

Topochemical reactions have led to great progress in the discovery of new metastable compounds with novel chemical and physical properties. With these reactions, the overall crystal structure of the host material is generally maintained. Here we report a topochemical synthesis of a hexagonal nitride hydride, h-Ca 3 CrN 3 H, by heating an orthorhombic nitride, o-Ca 3 CrN 3 , under hydrogen at 673 K, accompanied by a rotational structural transformation. The hydrogen intercalation modifies the Ca-N rock-salt-like atomic packing in o-Ca 3 CrN 3 to a face-sharing octahedral chain in h-Ca 3 CrN 3 H, mimicking a "hinged tessellation" movement. In addition, the h-Ca 3 CrN 3 H exhibited stable ammonia synthesis activity when used as a catalyst., (© 2022 Wiley-VCH GmbH.)

Background: Severe neonatal hyperbilirubinemia has been known to cause the clinical syndrome of kernicterus and a milder one the syndrome of bilirubin-induced neurologic dysfunction (BIND). BIND clinically manifests itself after the neonatal period as developmental delay, cognitive impairment, and related behavioral and psychiatric disorders. The complete picture of BIND is not clear., Methods: The Gunn rat is a mutant strain of the Wistar rat with the BIND phenotype, and it demonstrates abnormal behavior. We investigated serotonergic dysfunction in Gunn rats by pharmacological analyses and ex vivo neurochemical analyses., Results: Ketanserin, the 5-HT2AR antagonist, normalizes hyperlocomotion of Gunn rats. Both serotonin and its metabolites in the frontal cortex of Gunn rats were higher in concentrations than in control Wistar rats. The 5-HT2AR mRNA expression was downregulated without alteration of the protein abundance in the Gunn rat frontal cortex. The TPH2 protein level in the Gunn rat raphe region was significantly higher than that in the Wistar rat., Conclusions: It would be of value to be able to postulate that a therapeutic strategy for BIND disorders would be the restoration of brain regions affected by the serotonergic dysfunction to normal operation to prevent before or to normalize after onset of BIND manifestations., Impact: We demonstrated serotonergic dysregulation underlying hyperlocomotion in Gunn rats. This finding suggests that a therapeutic strategy for bilirubin-induced neurologic dysfunction (BIND) would be the restoration of brain regions affected by the serotonergic dysfunction to normal operation to prevent before or to normalize after the onset of the BIND manifestations. Ketanserin normalizes hyperlocomotion of Gunn rats. To our knowledge, this is the first study to demonstrate a hyperlocomotion link to serotonergic dysregulation in Gunn rats., (© 2021. The Author(s), under exclusive licence to the International Pediatric Research Foundation, Inc.)