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Dynamic cycling of O-linked β-N-acetylglucosamine (OGlcNAc) on nucleocytoplasmic proteins serves as a nutrient sensor to regulate numerous biological processes. However, mitochondrial protein O-GlcNAcylation and its effects on function are largely unexplored. In this study, we performed a comparative analysis of the proteome and OGlcNAcome of cardiac mitochondria from rats acutely (12 h) treated without or with thiamet-G (TMG), a potent and specific inhibitor of O-GlcNAcase. We then determined the functional consequences in mitochondria isolated from the two groups. O-GlcNAcomic profiling finds that over 88 mitochondrial proteins are O-GlcNAcylated, with the oxidative phosphorylation system as a major target. Moreover, in comparison with controls, cardiac mitochondria from TMGtreated rats did not exhibit altered protein abundance but showed overall elevated O-GlcNAcylation of many proteins. However, O-GlcNAc was unexpectedly down-regulated at certain sites of specific proteins. Concomitantly, TMG treatment resulted in significantly increased mitochondrial oxygen consumption rates, ATP production rates, and enhanced threshold for permeability transition pore opening by Ca2+. Our data reveal widespread and dynamic mitochondrial proteinO-GlcNAcylation, serving as a regulator to their function. [ABSTRACT FROM AUTHOR]

Contractile dysfunction and increased deposition of O-linked β-N-acetyl-d-glucosamine (O-GlcNAc) in cardiac proteins are a hallmark of the diabetic heart. However, whether and how this posttranslational alteration contributes to lower cardiac function remains unclear. Using a refined β-elimination/Michael addition with tandem mass tags (TMT)-labeling proteomic technique, we show that CpOGA, a bacterial analog of O-GlcNAcase (OGA) that cleaves O-GlcNAc in vivo, removes site-specific O-GlcNAcylation from myofilaments, restoring Ca(2+) sensitivity in streptozotocin (STZ) diabetic cardiac muscles. We report that in control rat hearts, O-GlcNAc and O-GlcNAc transferase (OGT) are mainly localized at the Z-line, whereas OGA is at the A-band. Conversely, in diabetic hearts O-GlcNAc levels are increased and OGT and OGA delocalized. Consistent changes were found in human diabetic hearts. STZ diabetic hearts display increased physical interactions of OGA with α-actin, tropomyosin, and myosin light chain 1, along with reduced OGT and increased OGA activities. Our study is the first to reveal that specific removal of O-GlcNAcylation restores myofilament response to Ca(2+) in diabetic hearts and that altered O-GlcNAcylation is due to the subcellular redistribution of OGT and OGA rather than to changes in their overall activities. Thus, preventing sarcomeric OGT and OGA displacement represents a new possible strategy for treating diabetic cardiomyopathy. [ABSTRACT FROM AUTHOR]

Elevated mitochondrial O-GlcNAcylation caused by hyperglycemia, as occurs in diabetes, significantly contributes to mitochondrial dysfunction and to diabetic cardiomyopathy. However, little is known about the enzymology of mitochondrial O-GlcNAcylation. Herein, we investigated the enzymes responsible for cycling O-GlcNAc on mitochondrial proteins and studied the mitochondrial transport of UDP-GlcNAc. Analyses of purified rat heart mitochondria from normal and streptozocin-treated diabetic rats show increased mitochondrial O-GlcNAc transferase (OGT) and a concomitant decrease in the mito-specific O-GlcNAcase (OGA). Strikingly, OGT is mislocalized in cardiac mitochondria from diabetic rats. Interaction of OGT and complex IV observed in normal rat heart mitochondria is visibly reduced in diabetic samples, where OGT is mislocalized to thematrix. Live cell OGA activity assays establish the presence of O-GlcNAcase within the mitochondria. Furthermore, we establish that the inner mitochondrial membrane transporter, pyrimidine nucleotide carrier, transports UDP-GlcNAc from the cytosol to the inside of the mitochondria. Knockdown of this transporter substantially lowers mitochondrial O-GlcNAcylation. Inhibition of OGT or OGA activity within neonatal rat cardiomyocytes significantly affects energy production, mitochondrial membrane potential, and mitochondrial oxygen consumption. These data suggest that cardiac mitochondria not only have robust O-GlcNAc cycling, but also that dysregulation of O-GlcNAcylation likely plays a key role in mitochondrial dysfunction associated with diabetes. [ABSTRACT FROM AUTHOR]

The article presents a study related to association of ACP1 gene polymorphisms and coronary artery disease (CAD) in northeast Chinese population. The findings include no significant difference in the ACP1 allele frequencies when compared to the distribution of the ACP1 alleles between CAD patients and control subjects, genotype of genetic algorithm (GA) may be a protective genotype against CAD, and genotype of GA polymorphism in ACP1 linked to reduced risk of CAD in Chinese population.

Intelligent bearing fault diagnosis is a necessary approach to ensure the stable operation of rotating machinery. However, it is usually difficult to collect fault data under actual working conditions, leading to a serious imbalance in training datasets, thus reducing the effectiveness of data-driven diagnostic methods. During the stage of data augmentation, a multi-scale progressive generative adversarial network (MS-PGAN) is used to learn the distribution mapping relationship from normal samples to fault samples with transfer learning, which stably generates fault samples at different scales for dataset augmentation through progressive adversarial training. During the stage of fault diagnosis, the MACNN-BiLSTM method is proposed, based on a multi-scale attention fusion mechanism that can adaptively fuse the local frequency features and global timing features extracted from the input signals of multiple scales to achieve fault diagnosis. Using the UConn and CWRU datasets, the proposed method achieves higher fault diagnosis accuracy than is achieved by several comparative methods on data augmentation and fault diagnosis. Experimental results demonstrate that the proposed method can stably generate high-quality spectrum signals and extract multi-scale features, with better classification accuracy, robustness, and generalization.

O-linked ß-D-N-acetylglucosamine (O-GlcNAc) modification (O-GlcNAcylation) onto serine and threonine residues of proteins is an important post-translational modification (PTM), which is involved in many crucial biological processes including transcription, translation, proteasomal degradation, and signal transduction. Aberrant protein O-GlcNAcylation is directly linked to the pathological progression of chronic diseases including diabetes, cancer, and neurodegenerative disorders. Identification, site mapping, and quantification of OGlcNAc proteins are a prerequisite to decipher their functions. In this review, we mainly focus on technological developments regarding O-GlcNAc protein profiling. Specifically, on one hand, we show how these techniques are being used for the comprehensive characterization of certain targeted proteins in which biologists are most interested. On the other hand, we present several newly developed approaches for O-GlcNAcomic profiling as well as how they provide us with a systems perspective to crosstalk amongst different PTMs and complicated biological events. Promising technical trends are also highlighted to evoke more efforts by diverse laboratories, which would further expand our understanding of the physiological and pathological roles of protein O-GlcNAcylation in chronic diseases. [ABSTRACT FROM AUTHOR]

Urban rail transit fare strategies include fare structures and fare levels. We propose a rail transit line fare decision based on an operating plan that falls under elastic demand. Combined with the train operation plan, considering flat fare and distance-based fare, and based on the benefit analysis of both passenger flow and operating enterprises, we construct the objective functions and build an optimization model in terms of the operators' interests, the system's efficiency, system regulation goals, and the system costs. The solving algorithm based on the simulated annealing algorithm is established. Using as an example the Changsha Metro Line 2, we analyzed the optimized results of different models under the two fare structures system. Finally the recommendations of fare strategies are given. [ABSTRACT FROM AUTHOR]

The solubility and digestion efficiency are two crucial factors that might affect the identification of integral membrane proteins (IMPs). In this work, 1% ( v/ v) ionic liquid (IL), 1-butyl-3-methyl imidazolium tetrafluoroborate (BMIM BF), added in NHHCO buffer (pH 8.3), was applied as a sample preparation buffer for IMPs analysis. Compared to the commonly used sodium dodecyl sulfate and methanol methods, the number of identified IMPs from rat brain by microcolumn reversed phase liquid chromatography (μRPLC)-electrospray ionization tandem mass spectrometry (ESI-MS/MS) was improved by over three times, which might be due to the fact that BMIM BF offered high solubilizing ability for IMPs and good compatibility for tryptic digestion. Furthermore, compared to Rapigest and urea methods, with BMIM BF method, the number of identified IMPs from rat brain could be improved 25% and 80%, respectively, which might be contributed to the good solubilizing ability and high thermal stability of such IL. With the sample treated by BMIM BF method, by 2D-nanoSCX-RPLC-ESI-MS/MS, 1,450 non-redundant proteins and 7,978 unique peptides were identified from rat brain, and 418 proteins contained at least one predicted transmembrane domain, with false discovery rates of less than 1% for peptide identification, and at least two identified unique peptides per protein. All these results demonstrate that the BMIM BF method is of high potential for the large-scale identification of IMPs. [ABSTRACT FROM AUTHOR]

In this study, zirconium oxide (ZrO) aerogel was synthesized via a green sol-gel approach, with zirconium oxychloride, instead of the commonly used alkoxide with high toxicity, as the precursor. With such material, phosphopeptides from the digests of 4 pmol of β-casein with the coexistence of 100 times (mol ratio) BSA could be selectively captured, and identified by MALDI-TOF MS. Due to the large surface area (416.0 m g) and the mesoporous structure (the average pore size of 10.2 nm) of ZrO aerogel, a 20-fold higher loading capacity for phosphopeptide, YKVPQLEIVPN[pS]AEER (MW 1952.12), was obtained compared to that of commercial ZrO microspheres (341.5 vs. 17.87 mg g). The metal oxide aerogel was further applied in the enrichment of phosphopeptides from 100 ng nonfat milk, and 17 phosphopeptides were positively identified, with a 1.5-fold improvement in phosphopeptide detection compared with previously reported results. These results demonstrate that ZrO aerogel can be a powerful enrichment material for phosphoproteome study. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Nanocrystalline Bi12TiO20 powders were successfully synthesized using an electrochemical method, where Bi and Ti plates were used as the anode and the cathode. Their crystallization and dispersion strongly rely on the H3PO4 amount in the electrolytic solution. Only large-sized Bi12TiO20 microspheres can be obtained without H3PO4, while adding H3PO4 in an electrolytic solution will destroy the dense microspheres and weaken the adhesion among primary particles, forming well-dispersed nanocrystalline Bi12TiO20. XRD and HRTEM evidenced the coexistence of body-centered cubic phase Bi12TiO20 with the face-centered cubic phase in nanocrystalline samples, and ultraviolet- Vis absorption and photodegradation data verified their good response to visible light and excellent photocatalytic ability. [ABSTRACT FROM AUTHOR]

In this study, a facile system for membrane proteome profiling was established, in which membrane proteins were solubilized by formic acid, online digested byapepsin-based immobilized enzyme reactor (pepsin-IMER), and analyzed by strong cation exchange and microflow reversed-phase liquid chromatography with elecirospray ionization tandem mass spectrometry (SCX-μRPLC-ESI-MS/MS). Under optimized conditions, such a system showed excellent compatibility between all cnicial steps and was successfully applied for analyzing integral membrane proteins extracted from rat liver microsomes. Out of the 235 unique proteins positively identified, 39% (91/235) were annotated as membrane proteins with one or more tinnsinembrane domains (TMDs). It is anticipated that the efficient sample treatment and the relevant online analytical system might provide a promising tool for automated and comprehensive profiling of membrane proteomes. [ABSTRACT FROM AUTHOR]

Yttrium orthovanadate (YVO4) nanoparticles with nearly spherical shape were successfully synthesized via a molten salt method at a low temperature of 200°C. The as-prepared powders were characterized by X-ray diffraction, transmission electron microscopy and UV-Vis spectroscopy, respectively. The results show that increasing salt amount and/or elevating calcining temperature can greatly promote the crystallization and growth of YVO4 phase. UV-Vis absorption spectra suggested that YVO4 nanoparticles with the smaller particle size have the stronger UV absorption, and the sequent photocatalytic degradation data also confirmed their higher photocatalytic activity. [ABSTRACT FROM AUTHOR]

Barium tungstate crystallites with different sizes and morphologies were successfully synthesized using a simple electrochemical technique by varying the components of electrolyte solutions. XRD analysis evidenced that the as-prepared samples were a pure tetragonal-phase of BaWO4 with a scheelite structure. Scanning electron microscopy images and PL spectra of BaWO4 crystallites revealed that the presence of OH− ions and the incorporation of absolute ethanol into the electrolyte solution would have important effects on their particle sizes, morphologies, and optical properties. [ABSTRACT FROM AUTHOR]

Barium tungstate (BaWO4) crystallites were successfully synthesized at room temperature via an easily-manipulated electrochemical method, using tungsten plates as electrodes and Ba(OH)2 solution as electrolyte. Effects of electric current value and reaction time on the crystallization and development of BaWO4 crystallites were initially studied and characterized by X-ray diffraction (XRD), scanning electron microscopy, and photoluminescent (PL) spectra technique, respectively. Experimental results showed that well-crystallized BaWO4 crystallites with ca. 2 μm in diameter could be obtained at 0.5 A and a short reaction time of 10 min. XRD analysis showed that the as-prepared sample was a pure tetragonal phase of BaWO4 with scheelite structure. PL spectra revealed that BaWO4 crystallites displayed a very strong PL peak at 448 nm with the 380 nm excitation wavelength. [ABSTRACT FROM AUTHOR]

Uniform Bi2S3 whiskers were synthesized via a template-free hydrothermal route using bismuth nitrate (Bi(NO3)3·5H2O), thiourea (CS(NH2)2), and lithium hydroxide (LiOH) as starting materials. The resultant powders were characterized in detail by X-ray diffraction, scanning electron microscopy, and photoluminescent spectra techniques (PL), respectively. It was found that Bi2S3 whiskers could be easily synthesized in the presence of LiOH, whereas only irregular and aggregated particles were obtained without adding LiOH, and that elevating hydrothermal reaction temperature in a certain range would promote the preferred orientation growth of Bi2S3 crystallites. The PL spectra results evidenced that the optical properties of Bi2S3 crystallites were obviously influenced by their size and morphology. [ABSTRACT FROM AUTHOR]

A novel kind of immobilized trypsin reactor based on organic-inorganic hybrid silica monoliths has been developed. With the presence of cetyltrimethyl ammonium bromide (CTAB) in the polymerization mixture, the hybrid silica monolithic support was prepared in a 100 m i.d. capillary by the sol-gel method with tetraethoxysilane (TEOS) and 3-aminopropyltriethoxysilane (APTES) as precursors. Subsequently, the monolith was activated by glutaraldehyde, and trypsin was covalently immobilized. By monitoring the reaction of a decapeptide, C-myc (EQKLISEEDL), the enzymatic activity of the immobilized trypsin was calculated, and the results showed that the digestion speed was about 6600 times faster than that performed in free solution. The performance of such a microreactor was further demonstrated by digesting myoglobin, with the digested products analyzed by microflow reversed-phase liquid chromatography coupled with tandem mass spectrometry (μRPLC-MS/MS). With a stringent threshold for the unambiguous identification of the digests, the yielding sequence coverage for on-column digestion was 92%, the same as that obtained by in-solution digestion, whereas the residence time of myoglobin in the former case was only 30 s, about 1/1440 of that performed in the latter case (12 h). Moreover, such an immobilized trypsin reactor was also successfully applied to the digestion of a mixture of model proteins and proteins extracted from E. coli. [ABSTRACT FROM AUTHOR]

Transmission spectra from equivalent negative refractive photonic crystals (PCs) composed of a triangular array of air cylinders in a GaAs matrix are studied by finite-difference time-domain method in the paper. Mechanism of wave resonance is probed and propagation of optical waves in the PCs is described in terms of effective refraction index and Bloch waves. Our numerical results show that probability of spontaneous radiation would be enhanced extremely under the influence of Bloch resonance waves, stimulated emission and photon tunnel effect, resulting in the optical waves localized greatly in the PCs at particular frequencies. In addition, we find out that the position of transmission peaks, with values far greater than unit, can be controlled by tuning the central frequency of waveguide source. It means that photon current in the PCs also can be controlled to optimize transmission properties of PCs, so as to meet the requirements of novel optical devices based on PCs. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

CdMoO4 powders with well-controlled shapes, including sphere, cake, cubic sugar, flake, and floccule have been successfully synthesized by a low-temperature (≤90°C) hydrothermal method. The effects of pH, reaction time, and temperature on the crystalline size and shape were explored by using X-ray powder diffraction and scanning electron microscopy. Room-temperature photoluminescence spectra of the as-synthesized CdMoO4 crystallites were also investigated, which showed that their optical properties obviously relied on the particle size and morphology of CdMoO4 powders. [ABSTRACT FROM AUTHOR]

Abstract??Distributed optical amplification from photonic-crystal fibers (PCFs) with layered structure composed of positive-and negative-refraction materials is studied by the finite-difference time-domain method. We found that the transmission spectra, with transmissivity far greater than unity at discrete transmission bands, have a band-gap structure with distributed gain, but the optical gain for defect modes is much smaller than that for transmitting modes, and maxima usually occur at the upper-and lower-band edges. This suggests that PCFs can be employed in dense wavelength-division multiplexed fiber-optics communication systems as transmission media carrying optical signals without crosstalk. [ABSTRACT FROM AUTHOR]

Well-crystallized bismuth tungstate (Bi2WO6) powders with different morphologies were successfully synthesized via a low-temperature molten salt method. The powders were characterized by X-ray diffraction, transmission electron microscopy, and UV-Vis, respectively. It was found that the variation of morphology of the obtained Bi2WO6 powder mainly depends on the different reaction temperatures and the weight ratio of LiNO3–NaNO3 salt to precursor. In addition, the UV-Visible absorption spectra showed that the synthesized powders had strong light absorption properties not only in the ultraviolet light but also in the visible light region. [ABSTRACT FROM AUTHOR]

Nano-crystalline LiNi0.5Mn1.5O4 with a unique powder characterization has been successfully synthesized by a soft combustion reaction method, using lithium nitrate, manganese nitrate, and nickel nitrate as the starting materials, and no organic materials being introduced in the whole process. The LiNi0.5Mn1.5O4 powders synthesized by the soft combustion reaction method were investigated by differential thermal analysis and thermogravimetry, X-ray diffractometer, and transmission electron microscopy. The resultant product was a pure phase of LiNi0.5Mn1.5O4 without any other impurities. Electrochemical measurements were also performed. [ABSTRACT FROM AUTHOR]

Nanostructured Sr2Nb2O7 powders with different morphologies were synthesized via a hydrothermal reaction at 200°C for 24 h in a Sr2+–Nb2O5· nH2O–KOH system. X-ray powder diffraction characterization indicated that 0.3–5 M KOH solutions favored the formation of a Sr2Nb2O7 pure phase. On increasing the concentration of KOH from 0.3 to 5 M, the morphology of Sr2Nb2O7 samples changed from nanoneedles to nanorods, nanosheets, and finally nano-sized flakes, and their aspect ratios gradually reduced. Ultraviolet–Visible diffuse reflectance spectra analyses showed that the nanostructured Sr2Nb2O7 powders had good light absorption properties in the ultraviolet light region. [ABSTRACT FROM AUTHOR]

CdMoO4 nano-particles were successfully synthesized by a hydrothermal process at a low temperature of 90°C, and the powders were characterized in detail by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and photoluminescent spectra techniques (PL), respectively. CdMoO4 particles could be obtained under the hydrothermal condition from micrometer to nanometer sizes by varying their precursors. The PL spectra results showed that the optical properties of CdMoO4 crystallites obviously relied on their particle sizes. [ABSTRACT FROM AUTHOR]

Nickel ferrite (NiFe2O4) nanoparticles were successfully synthesized via a hydrothermal process and characterized by X-ray diffraction and transmission electron microscope techniques. The effects of reaction temperature, holding time, and RH ratio (isopropyl alcohol/water) were discussed. The NiFe2O4 nanoparticles could be obtained at 60°C within 3 h. The crystallization of the spinel ferrites was promoted by the increase in reaction temperature, holding time, and RH ratio. [ABSTRACT FROM AUTHOR]

A newly developed molten salt method was applied at a temperature as low as 350°C to successfully synthesize an inverse spinel LiNiVO4 cathode by reacting lithium nitrate, nickel nitrate, and ammonium vanadate. As shown in XRD and TEM, the resultant product was a pure phase of LiNiVO4 without any other impurities. The powders showed a narrow particle size distribution with an average particle size of about 80 nm. No organic materials were introduced in the whole process. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the metabolic brain network and its relationship with depression symptoms using 18F-fluorodeoxyglucose positron emission tomography data in 78 pre-chemotherapy cancer patients with depression and 80 matched healthy subjects. Functional and structural imbalance or disruption of brain networks frequently occur following chemotherapy in cancer patients. However, few studies have focused on the topological organization of the metabolic brain network in cancer with depression, especially those without chemotherapy. The nodal and global parameters of the metabolic brain network were computed for cancer patients and healthy subjects. Significant decreases in metabolism were found in the frontal and temporal gyri in cancer patients compared with healthy subjects. Negative correlations between depression and metabolism were found predominantly in the inferior frontal and cuneus regions, whereas positive correlations were observed in several regions, primarily including the insula, hippocampus, amygdala, and middle temporal gyri. Furthermore, a higher clustering efficiency, longer path length, and fewer hubs were found in cancer patients compared with healthy subjects. The topological organization of the whole-brain metabolic networks may be disrupted in cancer. Finally, the present findings may provide a new avenue for exploring the neurobiological mechanism, which plays a key role in lessening the depression effects in pre-chemotherapy cancer patients.

Diabetes mellitus is the leading cause of cardiovascular and renal disease in the United -States. Despite the beneficial interventions available for patients with diabetes, there remains a need for additional therapeutic targets and therapies in diabetic kidney disease (DKD). Inflammation and oxidative stress are increasingly recognized as important causes of renal diseases. Inflammation is closely associated with mitochondrial damage. The molecular connection between inflammation and mitochondrial metabolism remains to be elucidated. Recently, nicotinamide adenine nucleotide (NAD+) metabolism has been found to regulate immune function and inflammation. In the present studies, we tested the hypothesis that enhancing NAD metabolism could prevent inflammation in and progression of DKD. We found that treatment of db/db mice with type 2 diabetes with nicotinamide riboside (NR) prevented several manifestations of kidney dysfunction (i.e., albuminuria, increased urinary kidney injury marker-1 (KIM1) excretion, and pathologic changes). These effects were associated with decreased inflammation, at least in part via inhibiting the activation of the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) signaling pathway. An antagonist of the serum stimulator of interferon genes (STING) and whole-body STING deletion in diabetic mice showed similar renoprotection. Further analysis found that NR increased SIRT3 activity and improved mitochondrial function, which led to decreased mitochondrial DNA damage, a trigger for mitochondrial DNA leakage which activates the cGAS-STING pathway. Overall, these data show that NR supplementation boosted NAD metabolism to augment mitochondrial function, reducing inflammation and thereby preventing the progression of diabetic kidney disease. [ABSTRACT FROM AUTHOR]

The protein tyrosine phosphatase SHP2 mediates multiple signal transductions in various cellular pathways, controlled by a variety of upstream inputs. SHP2 dysregulation is causative of different types of cancers and developmental disorders, making it a promising drug target. However, how SHP2 is modulated by its different regulators remains largely unknown. Here, we use single-molecule fluorescence resonance energy transfer and molecular dynamics simulations to investigate this question. We identify a partially open, semiactive conformation of SHP2 that is intermediate between the known open and closed states. We further demonstrate a "multiple gear" regulatory mechanism, in which different activators (e.g., insulin receptor substrate-1 and CagA), oncogenic mutations (e.g., E76A), and allosteric inhibitors (e.g., SHP099) can shift the equilibrium of the three conformational states and regulate SHP2 activity to different levels. Our work reveals the essential role of the intermediate state in fine-tuning the activity of SHP2, which may provide new opportunities for drug development for relevant cancers. [ABSTRACT FROM AUTHOR]