Search

Although metabolic disturbance is a characteristic of diabetic cardiomyopathy (DbCM), the detailed pathogenesis of DbCM remains unknown. We used a heart transplantation (HTx) cohort to explore the effect of diabetes mellitus on heart failure (HF) progression dependent of myocardium. Microscopic and ultramicroscopic pathology were used to depict the pathological features of human myocardium of DbCM. We performed targeted metabolomics to characterize the metabolic phenotype of human DbCM. Transcriptomics data were analyzed and weighted gene co-expression network analysis was performed to explore the potential upstream regulator for metabolic remodeling of DbCM. In vivo and in vitro experiments were further conducted to demonstrate the therapeutic effects and molecular mechanisms. DbCM promoted the progression of HF and increased death or HF-rehospitalization after HTx. Lipid accumulation and mitochondrial fission were the obvious pathological features of DbCM myocardium. The concentrations of C14:0-CoA and C16:1-CoA were significantly increased in the myocardium, and they were positively correlated with the accelerated HF progression and RCAN1 expression in DbCM patients. Knockdown of RCAN1 improved cardiac dysfunction, lipid accumulation, and mitochondrial fission in db/db mice. In vitro studies showed that RCAN1 knockdown improved mitochondrial dysfunction in DbCM cardiomyocytes via the RCAN1-p-Drp1 Ser616 axis. Diabetes is associated with faster progression of HF and causes poor prognosis after HTx, accompanied by metabolic remodeling in the myocardium. Accumulation of long chain acyl-CoA in the myocardium is the metabolic hallmark of human DbCM and is associated with more rapid disease progression for DbCM patients. Upregulation of RCAN1 in the myocardium is associated with the metabolic signatures of DbCM and RCAN1 is a potential therapeutic target for DbCM. [Display omitted] • Diabetes promotes non-diabetic heart failure after heart transplantation. • The increase in acyl-CoA is the metabolic hallmark of diabetic cardiomyopathy. • Knockdown of RCAN1 improved the cardiac function and structure of db/db mice. • RCAN1-p-Drp1 Ser616 axis contributes to mitochondrial dysfunction in cardiomyocytes. [ABSTRACT FROM AUTHOR]

Type 2 diabetes mellitus (T2DM) is one of the most risk factors threatening human health. Although genetic and environmental factors contribute to the development of T2DM, gut microbiota has also been found to be involved. Gut microbiota-derived metabolites are a key factor in host-microbe crosstalk, and have been revealed to play a central role in the physiology and physiopathology of T2DM. In this review, we provide a timely and comprehensive summary of the microbial metabolites that are protective or causative for T2DM, including some amino acids-derived metabolites, short-chain fatty acids, trimethylamine N-oxide, and bile acids. The mechanisms by which metabolites affect T2DM have been elaborated. Knowing more about these processes will increase our understanding of the causal relationship between gut microbiota and T2DM. Moreover, some frontier therapies that target gut microbes and their metabolites to improve T2DM, including dietary intervention, fecal microbiota transplantation, probiotics, prebiotics or synbiotics intervention, and drugging microbial metabolism, have been critically discussed. This review may provide novel insights for the development of targeted and personalized treatments for T2DM based on gut microbial metabolites. More high-quality clinical trials are needed to accelerate the clinical translation of gut-targeted therapies for T2DM. [Display omitted] • The key role of gut microbial metabolites in T2DM was comprehensively reviewed. • Graphically displayed the mechanisms by which microbial metabolites affect T2DM. • Targeting gut microbial metabolites provides a new strategy for treating T2DM. [ABSTRACT FROM AUTHOR]

The conventional anodic oxygen evolution reaction (OER) can be ideally replaced by the urea oxidation reaction (UOR) to achieve efficient hydrogen generation due to the superior thermodynamics. However, the UOR involves a slow 6-electron transfer dynamic, necessitating the utilization of high-performance catalysts to enhance catalytic efficiency. In this work, a bifunctional transition metal-based catalysts, namely, MoO 2 –NiO/NF heterostructure, is effectively synthesized using two-step hydrothermal methods and calcination. Benefiting from the heterogeneous interface, the nanoflower-like structure as well as the electron density redistribution, the MoO 2 –NiO/NF catalyst demonstrates remarkable durability and performance, with an overpotential of 139 mV to achieve 10 mA cm−2 for UOR. In addition, the bifunctional catalyst is used in a two-electrode electrolyzer, where a current density of 10 mA cm−2 is attained at a potential of 1.317 V, which is 261 mV smaller than that of the conventional water splitting system. Based on the density functional theory (DFT) calculations, the MoO 2 –NiO/NF heterostructure exhibits a higher density cloud in the vicinity of the Fermi level, revealing that it has faster electron transfer and higher electrical conductivity. Besides, the Mo sites and Ni sites are favorable for adsorption of CO(NH 2) 2 and H 2 O, respectively, which might optimize the reaction intermediates adsorption/desorption for UOR/HER, ultimately leading to the high electrocatalytic performance of MoO 2 –NiO/NF. This research opens a new window for the development of advanced heterojunction electrocatalysts assisted by urea electrocatalysis for cost-effective hydrogen production. Using hydrothermal and calcination techniques, high-performance MoO 2 –NiO/NF nanoflower-like heterostructures for bifunctional urea-assisted water splitting are created. In the HER||UOR two-electrode system, the MoO 2 –NiO/NF heterostructure only required 1.32 V at 10 mA cm−2, which is about 261 mV smaller than that of the traditional water electrolysis. [Display omitted] • Heterostructured nanoflower-like MoO 2 –NiO/NF electrocatalyst is synthesized. • MoO 2 –NiO/NF shows superb activity and stability in urea-assisted water splitting. • The bifunctional catalyst exhibits enhanced electrocatalytic HER/UOR performance. • Heterointerface has fast electron transfer and high electrical conductivity. • Mo and Ni sites are selective for the adsorption of urea and H 2 O molecules. [ABSTRACT FROM AUTHOR]

Molecular hydrogen is of critical importance in the chemical industry and might play vital role in future for benign and secure energy technologies. However, its generation from renewable sources, such as water and biomass without the addition of external energy (heat, light and electricity) remains difficult. Herein, we report that Group VIII and Group IB transition metal nanoparticles supported on magnesium oxide are active all-solid-state catalyst systems for external energy-free liberation of molecular hydrogen by aldehyde reforming in liquid water at ambient conditions. Based on experimental observation and DFT calculation, it is suggested that molecular oxygen as well as water can be readily reduced on Group IB metals via two-electron process to form peroxy radicals, while most of Group VIII metals such as Pt end up with sites creating oxo species but instead form hydroxyl radicals via four-electron processes. Therefore, by altering supporting metals, we are able to control the reaction pathways (reduction of aldehydes into H 2 or oxidation of aldehydes into CO 2 ) due to the difference of oxygen reduction products. [ABSTRACT FROM AUTHOR]

The sound quality of automotive transmission noise strongly influences passengers' psychological and physiological perceptions. To predict the sound quality of automotive transmission noise, a uniform deceleration noise test with two automotive transmissions has been conducted in a semi-anechoic room. All recorded transmission noise signals have been divided into 5 s segments and subsequently evaluated subjectively through the rating scales test by a jury. In addition, a novel prediction method, namely, Mel-Frequency Cepstral Coefficients-based convolutional neural networks (MFCC-CNN), which substitute the softmax classification layer for the linear transform prediction layer at the output of the general CNN's structure and take MFCC feature map as input, has been proposed to predict the transmission sound quality. MFCC's distinguishing performance on sound quality has been validated. The parameter selection of the MFCC-CNN model has been compared and studied using a grid search. In addition, three conventional machine-learning-based methods have been introduced to enable a comparison of the performance with the newly developed MFCC-CNN. The results show the following: (1) In different transmission gears, MFCC features can distinguish different sound quality noises. (2) The accuracy of the proposed MFCC-CNN sound quality prediction approach are better than those of the 3 other referenced methods. (3) The correlation coefficient of prediction value from MFCC-CNN is more than 0.95 and the mean absolute error of prediction value from MFCC-CNN is less than 0.55, which fully meets the need of engineering. Finally, the newly proposed MFCC-CNN approach may be extended to address other vehicle noises in the future. [ABSTRACT FROM AUTHOR]

Background Serological analysis of ABO blood group has been widely applied in transfusion medicine. However, ABO subgroups with different expression of blood group antigens sometimes cannot be determined by serological methods. Therefore, genotyping is useful to understand the variant ABO phenotypes. Material and Methods Exon 6 to exon 7 and adjacent introns of the ABO gene from a donor with ABO typing discrepancy were amplified and sequenced. Cloning sequencing was also performed to identify the allele. To explore the effect of mutation, three dimensional model of mutant p.Pro234Ala was built and optimized. Results The variant B (c. 700C > G) allele expressed an AweakB phenotype with anti-A in his serum with a ABO*B(A)02/O02 heterozygote genotype. Cloning sequencing confirmed that the c.700C > G single nucleotide polymorphism was associated with a B101 allele. Three dimensional molecular modeling suggested that p.Pro234Ala might affect the conformation of His233, Met266 and Ala268, which were known as critical residues for donor recognition. Conclusion ABO genotyping is needed for correct identification subgroups to improve accuracy evaluation of blood typing and increase the safety of blood transfusion. Alteration of DNA sequence in the ABO gene resulted in amino acid substitutions and led to a weak or missing expression of ABO antigens. [ABSTRACT FROM AUTHOR]

In this work, a three-dimensional TiO 2 -graphene composite with large specific surface area is designed by freeze drying. In this architecture, primary TiO 2 nanoparticles (less than 10 nm in size) are wrapped with graphene homogeneously, forming spherical secondary particles (≈100 nm), and the spherical TiO 2 particles further agglomerate into platelet-like particles with several micrometers in size. The TiO 2 -graphene composite delivers high de-lithiation and de-sodiation capacities of 312 mAh g−1 and 280 mAh g−1 at 17 mA g−1 as negative electrode materials in lithium and sodium cells, respectively, and excellent cycling performance with negligible capacity loss after 500 cycles at a specific current of 85 mA g−1. When coupled with an activated carbon positive electrode, it demonstrates high capacitance and long cycle life in sodium ion capacitors (81% after 2000 cycles at 1 A g−1) and lithium ion capacitors (95% after 5000 cycles at 1 A g−1). Its superior performance benefits from the designed 3D architecture, which combines the advantages of small primary particle size, a homogeneous carbon coating and an adequate contact area with the liquid electrolyte. The storage mechanisms of the superior TiO 2 -graphene composite in lithium and sodium cells are investigated by operando X-ray diffraction studies. • A three-dimensional TiO 2 -graphene composite is prepared by freeze drying. • The composite has large specific surface area and platelet-like morphology. • Na/Li cells and Na/Li ion capacitors using the composite are assembled. • Superior electrochemical performance of the composite in these cells is achieved. [ABSTRACT FROM AUTHOR]