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A series of hydroxyl-terminated polyethylenes (HTPE) bearing various functional side groups (e.g. carboxyl, ester and butane groups) were synthesized by the combination of ring-opening metathesis polymerization (ROMP) and visible light photocatalytic thiol-ene reaction. The products are named as α, ω-dihydroxyl-poly[(propionyloxythio)methinetrimethylene] (HTPEcarboxyl), α, ω-dihydroxyl-poly[(methylpropionatethio) methinetrimethylene] (HTPEester) and α, ω-dihydroxyl-poly[(butylthio) methinetrimethylene] (HTPEbutane), respectively. The investigation of ROMP indicated that the molecular weight of resultant hydroxyl-terminated polybutadiene (HTPB) can be tailored by varying the feed ratios of monomer to chain transfer agent (CTA). The exploration of the photocatalytic thiol-ene reaction between HTPB precursor and methyl 3-mercaptopropionate revealed that blue light as well as oxygen accelerated the reaction. 1H-NMR and 13C-NMR results verified all the double bonds in HTPB can be modified, and the main chain of resultant polymer can be considered as polyethylene. Subsequently, relationship between the structure of side groups and the thermal properties of functional PEs was studied. And the results suggested that the Tg was in the order of HTPEbutane

Anaerobic methane oxidation is coupled to the reduction of electron acceptors, such as sulfate, and contributes to their biogeochemical cycling in the environment. However, whether arsenate acts as an alternative electron acceptor of anaerobic methane oxidation and how this influences global arsenic transformations remains elusive. Here, we present incubations of arsenate-contaminated wetland soils from seven provinces in China. Using isotopically labelled methane, we find that anaerobic methane oxidation was linked to arsenate reduction at a rate approaching the theoretical arsenic/methane stoichiometric ratio of 4. In microcosm incubations with natural wetland soils, we find that the coupled pathway of anaerobic methane oxidation and arsenate reduction contributed 26 to 49% of total arsenic release from soils, with arsenic in the more soluble and toxic form arsenite. Comparative gene quantification and metagenomic sequencing suggest that the coupled pathway was facilitated by anaerobic methanotrophs, either independently or synergistically with arsenate-reducing bacteria through reverse methanogenesis and respiratory arsenate reduction. Further bioinformatic analyses show that genes coding for reverse methanogenesis and respiratory arsenate reduction are universally co-distributed in nature. This suggests that coupling of anaerobic methane oxidation and arsenate reduction is a potentially global but previously overlooked process, with implications for arsenic mobilization and environmental contamination. The coupling of anaerobic oxidation of methane and arsenate reduction is an important pathway of releasing arsenic from soils, according to incubation experiments of arsenate-contaminated wetland soils.

This study examined anti-cancer compounds present in the chloroform extract of the Chinese medicine formula Shenqi San (CE-SS). Silica gel column chromatography, Sephadex LH-20, octadecylsilyl (ODS) column chromatography, and high performance liquid chromatography (HPLC) were used to separate the compounds from CE-SS. The structural formulas of the separated compounds were determined using 1D 1H and 13C experiments as well as high resolution electrospray ionization mass spectroscopy (HRESIMS). The corresponding results were compared with the reported literature data. A total of six compounds were separated and their structures were identified on the basis of corresponding spectroscopic and physico-chemical properties. They were Saikogenin F (I), Prosaikogenin D (II), Prosaikogenin F (III), β-sitosterol (IV), 3β,16β,23-trihydroxy-13,28-epoxyurs-11-ene-3-O-β-D-glucopyranoside (V), and methyl ursolic acid (VI). The separated compounds were evaluated in vitro for their inhibitory ability against the proliferation of A549 cells via MTT assay. Apoptosis was investigated using Annexin V-FITC/propidium iodide (PI) by flow cytometry. Apoptosis-associated proteins were examined by Western blotting. All the compounds were observed to have inhibitory activities against the proliferation of A549 cells to different degrees. Flow cytometry showed that compound V increased the proportion of apoptotic A549 cells in a dose-dependent manner. Western blotting showed that compound V increased the expression of Bax, cleaved-caspase-3, cleaved-caspase-9 and cleaved-poly ADP-ribose polymerase (PARP), and decreased the expression of Bcl-2. These results indicated that compound V featured a significant inhibitory effect on A549 cells when compared with other compounds, and it may be considered a potential drug against cancers.

Surgical pleth index (SPI) has been widely investigated in assessing the nociceptive level. The aim of this study was to investigate the relationship between SPI level and patient responses to trachea intubation and skin incision. A total of 40 patients undergoing open abdominal general surgery were recruited for analyses. The patients were monitored with electrocardiogram, non-invasive blood pressure, SpO2, invasive blood pressure and SPI before anesthesia induction. Anesthesia was induced with midazolam, propofol, sufentanil and rocuronium and maintained with sufentanil and sevoflurane. Blood pressure, heart rate and SPI were recorded for analyses during the peri-intubation and peri-incision periods. A receiver operating characteristic (ROC) curve analysis was performed to analyze the predictive value of blood pressure, heart rate (HR) and SPI for hemodynamic responses for trachea intubation and skin incision. SPI had a similar changing trend to systolic blood pressure (SBP) and diastolic blood pressure (DBP). The SPI level was linearly correlated with SBP, DBP and HR. SPI increased significantly after intubation and incision in patients with positive but not negative responses to intubation and incision. The ROC analysis showed that only SBP level is predictive of intubation responses. These data suggested that SPI elevated under the noxious stimulation by intubation and incision, but it was not predictive of the hemodynamic responses to intubation and incision.

A type of rock landslide is very common in practical engineering, whose stability is mainly controlled by the rock bridge between the steep tensile crack at the crest and the low-inclination weak discontinuities at the toe (namely, ligament is the term for the locking section in the slope). To obtain a deeper understanding into the failure process of this kind of landslide, twenty-four physical slope models containing a steep-gentle discontinuity pair (a steep crack in the upper part and a low-inclination discontinuity in the lower part) were tested by applying vertical loads at the crests. The results indicate that the inclination angle of the ligament (θ) has great influence on the failure and stability of this type of rock slope. With the change of θ, three failure patterns (five subtypes) concerning the tested slopes can be observed, i.e., tensile failure of the ligament (Type 1), tension-shear failure of the ligament (Type 2) and two-stage failure of the main body (Type 3). The failure process of each failure mode presents five stages in terms of crack development, vertical load, horizontal/vertical displacements and strains in the ligaments. The specific range of the ligament angle between different failure patterns is summarized. The discussion on the failure resistances and ductility of different failure patterns, and the guiding significances of the experimental findings to the stability evaluation and the reinforcement were conducted.

The mechanism and charge effect of cycloisomerization of ω-alkynylfuran (Hashmi phenol synthesis) catalyzed by single-walled helical gold nanotubes (Au SWNTs) have been systematically investigated via density functional theory. Cycloisomerization of ω-alkynylfuran occurs by the 5-exo Friedel–Crafts-type (FCT) mechanism, namely 5-exo cyclization, furan ring opening, and ring closing of the dienone carbene–gold intermediate. The reactions with Au(6,0), Au(6,1), Au(6,2) and Au(6,3) SWNTs show low energy barriers along the 5-exo FCT path in acetonitrile solvent, but have different the rate-determining steps. From an energy perspective, the reaction rate-determining step catalyzed by Au(6,0) and Au(6,3) is the ring-closing of dienone carbine-gold intermediate, but that of Au(6,1) and Au(6,2) is the IM5 dissociation from the Au SWNTs, which can be attributed to the diversity of the d-band centers of the Au(6,m) SWNTs. The effect of the charge of the Au SWNTs on the catalytic activity was also investigated. Theoretical analysis shows a prominent charge effect, where the cationic Au(6,0), Au(6,3) SWNTs and anionic Au(6,1), Au(6,2) SWNTs are more favorable for the Hashmi phenol synthesis reaction. This results can be attributed to the Au(6,0) and Au(6,3) SWNTs with positive charge can reduce the adsorption energy of the substrate on the catalyst surface and decrease the energy barrier of the cyclization process and ring-closing step. Besides, the Au(6,1) and Au(6,2) with an anion could obviously decrease the dissociation energy of IM5 which is help for the Hashmi phenol reaction. Theoretical analysis shows that the structure and charge effects could influence the catalytic activity of Au(6,m) SWNTs toward Hashmi phenol synthesis. This work will provide insight into cycloisomerization of ω-alkynylfuran and valuable information for application of Au SWNTs in catalysis.

Searching for new cathode materials is very important in the field of Na-ion batteries. Transition metal sodium orthosilicates have attracted much attention due to the significant progress made in its analog of lithium orthosilicates. In this work, density functional theory (DFT) calculations are performed to study the structural stabilities, electronic and electrochemical properties of Na2FeSiO4 polymorphs, and their corresponding desodiated products Na x FeSiO4. Our results show that formation energies of all the calculated structures differ substantially upon removal of Na, indicating that phase transformations should happen during the desodiation for different polymorphs. NaFeSiO4 is the only energetically stable intermediate phase among the cases, leading to two theoretically voltage plateaus, i.e., ~ 2.0 V (2 ≥ x ≥ 1) and ~ 4.5 V (1 ≥ x ≥ 0) in Na x FeSiO4, respectively. Moreover, the oxidation of Fe2+ to Fe3+ ions is observed during the removal of the first Na ion, while both the oxidation of O and Fe ions occur during the further desodiation.

The main purpose of this study was to investigate the active components of the Chinese medicine formula Shenqi San (SS) by high performance liquid chromatography with diode array detector and electrospray ionization-hybrid quadrupole time-of-flight mass spectrum (HPLC-DADESI- QTOF-MS), and demonstrate the anticancer mechanism of SS on human lung adenocarcinoma A549 cells by evaluating the cell proliferation and apoptosis induction. The chloroform extraction of SS (CE-SS) was extracted from SS, while HPLC-DAD-ESI-QTOF-MS assay was performed to identify components of CE-SS. MTT assay was used to quantify the proliferation of A549 cells with the treatment of CE-SS. Apoptosis analysis was carried out by detecting phosphatidylserine (PS) externalization using the Annexin V-FITC Apoptosis Detection Kit and the stained cells were analyzed with a flow cytometer. DAPI staining assay was carried out to observe morphological characteristics of apoptotic cells. Western blotting was used to detect the expression of important signaling proteins including caspase-3, -8, -9, p53, Bax and Bcl-2. Eight compounds were identified through HPLC-DAD-ESI-QTOF-MS analysis and 3-pyridine carboxylic acid, barbatin C, scutebarbatine F and barbatine D might be the main compounds responsible for the antitumor effect of CE-SS. CE-SS suppressed the proliferation of lung cancer A549 cells in a time- and dose-dependent manner. By Annexin V-FITC/PI double staining, we found that treatment with CE-SS induced apoptosis in A549 cells. After 24-h exposure to CE-SS, the expression of cleaved-caspase-9, cleaved-caspase-8 and cleaved-caspase-3 protein was activated, the expression of p53 protein increased while the ratio of Bax/Bcl-2 also increased. This study identified the eight compounds of CE-SS, and demonstrated their anticancer effect on human lung adenocarcinoma A549 cells via induction of apoptosis.

From the perspective of the cost analysis of commodity marketing, the logistics cost accounts for about 30% of the final price of commodities, and the cost of storage selection accounts for about 75% of all logistics costs. This means that the management of the operation efficiency of storage is an essential part of logistics management. With four different modified fruit fly optimization algorithms, this study aimed to optimize the logistics storage selection. First, this study selected 10, 20, and 30 freight sections in a random manner; second, four fruit fly optimization algorithms were used to create some populations and fruit flies, which were taken as freight section spots; third, the algorithms were adopted to seek the logistics storage selection that costs the shortest time. According to analysis of the result, the chaos fruit fly algorithm, out of the four, was the one that took the shortest time and created the greatest effect when 10, 20, or 30 freight sections were considered. The 100 repetitious experiments also demonstrated that the chaos fruit fly algorithm cost the shortest time in the selection, and had the lowest time value variable.

Factors leading to the formation of a hexahydroaporphine-like cyclizing side product were studied systematically for the first time and the ratio of this side product was controlled effectively. To understand better the electronic effect of substrates on the formation of side products, different 1-benzyloctahydroisoquinolines with substituted groups on nitrogen or benzene ring were compared. A plausible mechanism of cyclizing reaction was proposed, and key intermediates as well as transition states were analyzed using DFT calculations.

Four series of heterocyclic compounds were obtained using Ugi-type multicomponent reactions (MCRs) with methyl 2-formylbenzoate as one of the starting materials. A facile and efficient one-pot procedure was suitable for all the MCRs under acidic conditions. This process provided access to four series of complex and potentially biologically active scaffolds.

The spatial and temporal trends of 11 (7) temperature (precipitation) extreme indices are examined for the Loess Plateau Region (LPR) and its southeast and northwest sub-regions based on daily observations at 214 meteorological stations. Results show widespread significant warming trends for all the temperature extremes except for the diurnal temperature range (DTR) and the lowest daily maximum temperature in each year (TXn) during 1961–2010. When regionally averaged, a significant warming trend is detected for all the indices except for DTR and TXn in the past 50 years. Compared with the entire LPR, a significant warming trend is detected for all the indices except for DTR and TXn over the southeast sub-region of LPR; while it is observed for all the indices over the northwest. The trends for these indices are generally stronger in the northwest than in the southeast in the past 50 years. In contrast, for precipitation indices, only a small percentage of areas show significant drying or wetting trends and, when regionally averaged, none of them displays significant trends during the past 50 years. On the sub-regional scale, however, a larger percentage of areas show significant drying trends for precipitation indices generally over the southeast relative to the entire LPR, and noticeably, the sub-regional average heavy precipitation (R10mm) and wet day precipitation (PRCPTOT) display significant decreasing trends during the past 50 years; whereas only a slightly larger percentage of areas show significant wetting trends for these indices over the northwest compared with the entire LPR, and when sub-regionally averaged, none of the indices have significant trends during the past 50 years.

The assembly of spherical fullerenes, or buckyballs, into single crystals for crystallographic identification often suffers from disordered arrangement. Here we show a chiral configuration of decapyrrylcorannulene that has a concave ‘palm’ of corannulene and ten flexible electron-rich pyrryl group ‘fingers’ to mimic the smart molecular ‘hands’ for self-adaptably cradling various buckyballs in a (+)hand-ball-hand(−) mode. As exemplified by crystallographic identification of 15 buckyball structures representing pristine, exohedral, endohedral, dimeric and hetero-derivatization, the pyrryl groups twist with varying dihedral angles to adjust the interaction between decapyrrylcorannulene and fullerene. The self-adaptable electron-rich pyrryl groups, susceptible to methylation, are theoretically revealed to contribute more than the bowl-shaped palm of the corannulene in holding buckyball structures. The generality of the present decapyrrylcorannulene host with flexible pyrryl groups facilitates the visualization of numerous unknown/unsolved fullerenes by crystallography and the assembly of the otherwise close-packed spherical fullerenes into two-dimensional layered structures by intercalation., The structures of fullerenes, or buckyballs, are often very difficult to resolve. Here, the authors describe a decapyrrylcorannulene host with ten flexible pyrryl groups that can efficiently co-crystallize with diverse fullerene derivatives in a ‘hand-ball-hand’ fashion, allowing crystallographic identification of commonly known types of fullerenes.

The electronic properties of vanadium atoms adsorbed on clean and graphene-covered Cu(111) surface have been systematically studied using ab initio theoretical method. Two coverages (1/9 ML and 1 ML) of vanadium adsorption are considered in this work. Our calculations indicate that V staying underneath the Cu surface is found to be the most stable adsorption site at the aforementioned two coverages for V/Cu(111). However, such adsorption may lead to undesired properties. Therefore, we introduce graphene as a buffer layer to effectively alleviate the direct interaction between V and Cu surface. The calculations show that electronic properties of the original graphene layer are significantly affected by the interactions of C atoms with the V adatoms; the Dirac point of graphene is “destroyed” as a consequence at both coverages. In the V/Gra/Cu(111) system, the interaction between graphene layer and the substrate Cu atoms remains weak as in the Gra/Cu(111) system. Moreover, a relatively low coverage of 1/9 ML gives rise to a spin-polarized system while a non-spin-polarized system is observed at the coverage of 1 ML. This finding offers a new way for the application of vanadium-based materials in reality.

During pathological conditions, extracellular-5'-nucleotidase/CD73 can protect neurons by reducing the permeability of the blood brain barrier. In recent years, it has been demonstrated that CD73 can negatively contribute to the growth of gliomas; however, the function of CD73 in glioma blood vessels is not clear. We analysed the expression of CD73 in 72 glioma patients using immunohistochemistry and correspondingly compared the results with the Edema index (EI). We established an in vitro model of the blood-tumour barrier and analysed the expression of CD73 in vascular endothelial cells. Lastly, CD73 expression was inhibited in endothelial cells, and the effects of this inhibition on tight junction structure and transendothelial resistance were observed. Compared to normal brains, the expression of CD73 in blood vessels of glioma patients was significantly decreased, and the amount was lower in the centre of the tumour than the periphery. The proportion of CD73-positive blood vessels had a positive correlation with the EI. The expression of CD73 in the in vitro endothelial cell blood-tumour barrier model was decreased. Lastly, inhibiting CD73 was found to decrease the expression of tight junction related proteins in endothelial cells and to decrease the value of transendothelial electric resistance. The expression of CD73 in glioma blood vessels was significantly decreased, which may play a multi-functional role in decreasing the expression of tight junction related proteins of brain microvascular endothelial cells and may also increase blood-tumour barrier permeability and accelerate the formation of PTBE.

Two series of fused benzimidazoles were synthesized via a facile, one-pot procedure under microwave irradiation. This procedure generated the desired products in high yields and could provide a useful synthetic platform with potential applications in medicinal chemistry.

(Lu0.95Tb0.05)3(Al0.80Ga0.20)5O12 (LuAGG:Tb) phosphor is synthesized by a high-temperature solid-state reaction, and a thin layer of niobium-doped TiO2 (NTO) is deposited on the phosphor particles by coprecipitation-assisted solvothermal synthesis. The crystal structure, micromorphology, chemical bonding, and cathodoluminescent (CL) properties of both the uncoated and NTO-coated phosphors are determined. The phosphor powders possess a single phase, and the average diameter of the particles is about 3 μm. NTO nanoparticles with the anatase crystal structure are connected to the phosphor particles electrostatically. Both types of phosphors exhibit the characteristic emission spectrum of Tb3+ under electron excitation. The CL intensity decreases, whereas the resistance to luminance saturation and degradation increases with the coating.

A series of compounds containing the 1H-pyrazino[1,2-a]quinoxaline-1,5(6H)-dione scaffold have been synthesized using a one-pot procedure under microwave irradiation. This new strategy allowed for the facile synthesis of target compounds in good yields and could be readily applied to the construction of diverse libraries of compounds for high throughput screening in medicinal chemistry.

The Eu3+-doped and Eu3+, Bi3+ co-doped Lu3M5O12 (LuMG where M = Al, Ga) phosphors are synthesized by spray pyrolysis, and the crystal structure, micromorphology, luminescence properties and effects of Bi3+ co-dopant are investigated. X-ray diffraction reveals that the crystal structures of the matrices do not change after partial replacement of Lu3+ by Eu3+ and Bi3+. The phosphors exhibit the same spherical micromorphology without agglomeration and particle size distribution with a typical diameter of about 0.7 μm. The emission and excitation spectra show transitions associated with the Eu3+ 4f configurations. 7F1 energy level splitting of Eu3+ in Lu3Al5O12:Eu and stronger luminescence of Lu3Ga5O12:Eu are observed, and the quenching concentrations of Eu3+ in Lu3Al5O12:Eu and Lu3Ga5O12:Eu are 6 and 10 mol% with respect to Lu3+, respectively. Introduction of Bi3+ enhances the emission of Eu3+ accompanied by the transition emission of Bi3+.

For a connected simple graph G, the eccentricity ec(v) of a vertex v in G is the distance from v to a vertex farthest from v, and d(v) denotes the degree of a vertex v. The eccentric connectivity index of G, denoted by ξ c (G), is defined as Σ v∈V(G) d(v)ec(v). In this paper, we will determine the graphs with maximal eccentric connectivity index among the connected graphs with n vertices and m edges(n ≤ m ≤ n+4), and propose a conjecture on the graphs with maximal eccentric connectivity index among the connected graphs with n vertices and m edges (m ≥ n +5).

LYR motif-containing 1 (LYRM1) was recently discovered to be involved in adipose tissue homeostasis and obesity-associated insulin resistance. We previously demonstrated that LYRM1 overexpression might contribute to insulin resistance and mitochondrial dysfunction. Additionally, knockdown of LYRM1 enhanced insulin sensitivity and mitochondrial function in 3T3-L1 adipocytes. We investigated whether knockdown of LYRM1 in 3T3-L1 adipocytes could rescue insulin resistance and mitochondrial dysfunction induced by the cyanide p-trifluoromethoxyphenyl-hydrazone (FCCP), a mitochondrion uncoupler, to further ascertain the mechanism by which LYRM1 is involved in obesity-associated insulin resistance. Incubation of 3T3-L1 adipocytes with 1 µM FCCP for 12 h decreased insulin-stimulated glucose uptake, reduced intracellular ATP synthesis, increased intracellular reactive oxygen species (ROS) production, impaired insulin-stimulated Glucose transporter type 4 (GLUT4) translocation, and diminished insulin-stimulated tyrosine phosphorylation of Insulin receptor substrate-1 (IRS-1) and serine phosphorylation of Protein Kinase B (Akt). Knockdown of LYRM1 restored insulin-stimulated glucose uptake, rescued intracellular ATP synthesis, reduced intracellular ROS production, restored insulin-stimulated GLUT4 translocation, and rescued insulin-stimulated tyrosine phosphorylation of IRS-1 and serine phosphorylation of Akt in FCCP-treated 3T3-L1 adipocytes. This study indicates that FCCP-induced mitochondrial dysfunction and insulin resistance are ameliorated by knockdown of LYRM1.

Na-ion battery cathode material NaFeF3 and the corresponding desodiated products were investigated by using first-principle density functional theory calculations within the generalized gradient approximation (GGA) + U framework. Our results show that Na0.5FeF3 is the only energetically stable intermediate phase among the cases considered in the present work (x = 0.75, 0.5, 0.25), leading to theoretically two voltage plateaus, i.e., 2.63 V (1 ≥ x ≥ 0.5) and 2.82 V (0.5 ≥ x ≥ 0) in Na x FeF3, respectively. The mean charge voltage of the extraction of the first 0.5 Na ions agrees well with the experimental value, but the one of the extraction of the second 0.5 Na ions exhibits a relatively low value comparing to the experimental results, indicating that another end phase exists, which is consistent with the recent experiments. Furthermore, the electronic structures upon the desodiation are also discussed, and charge localization into distinct Fe2+ and Fe3+ is found in the intermediate-phase Na0.5FeF3.

Aiming at the potential presence of mixing automatic identification system (AIS) signals, a new demodulation scheme was proposed for separating other interfering signals in satellite systems. The combined iterative cross-correlation demodulation scheme, referred to as CICCD, yielded a set of single short signals based on the prior information of AIS, after the frequency, code rate and modulation index were estimated. It demodulates the corresponding short codes according to the maximum peak of cross-correlation, which is simple and easy to implement. Numerical simulations show that the bit error rate of proposed algorithm improves by about 40% compared with existing ones, and about 3 dB beyond the standard AIS receiver. In addition, the proposed demodulation scheme shows the satisfying performance and engineering value in mixing AIS environment and can also perform well in low signal-to-noise conditions.

NYGGF4 (also called PID1) is a recently discovered gene that is involved in obesity-related insulin resistance (IR). We aimed in the present study to further elucidate the effects of NYGGF4 on IR and the underlying mechanisms through using metformin treatment in 3T3-L1 adipocytes. Our data showed that the metformin pretreatment strikingly enhanced insulin-stimulated glucose uptake through increasing GLUT4 translocation to the PM in NYGGF4 overexpression adipocytes. NYGGF4 overexpression resulted in significant inhibition of tyrosine phosphorylation of IRS-1 and serine phosphorylation of Akt, whereas incubation with metformin strongly activated IRS-1 and Akt phosphorylation in NYGGF4 overexpression adipocytes. The reactive oxygen species (ROS) levels in NYGGF4 overexpression adipocytes were strikingly enhanced, which could be decreased by the metformin pretreatment. Our data also showed that metformin increased the expressions of PGC1-α, NRF-1, and TFAM, which were reduced in the NYGGF4 overexpression adipocytes. These results suggest that NYGGF4 plays a role in IR and its effects on IR could be reversed by metformin through activating IRS-1/PI3K/Akt and AMPK-PGC1-α pathways.

Transplantation studies in mice and rats have shown that human embryonic-stem-cell-derived cardiomyocytes (hESC-CMs) can improve the function of infarcted hearts, but two critical issues related to their electrophysiological behaviour in vivo remain unresolved. First, the risk of arrhythmias following hESC-CM transplantation in injured hearts has not been determined. Second, the electromechanical integration of hESC-CMs in injured hearts has not been demonstrated, so it is unclear whether these cells improve contractile function directly through addition of new force-generating units. Here we use a guinea-pig model to show that hESC-CM grafts in injured hearts protect against arrhythmias and can contract synchronously with host muscle. Injured hearts with hESC-CM grafts show improved mechanical function and a significantly reduced incidence of both spontaneous and induced ventricular tachycardia. To assess the activity of hESC-CM grafts in vivo, we transplanted hESC-CMs expressing the genetically encoded calcium sensor, GCaMP3 (refs 4, 5). By correlating the GCaMP3 fluorescent signal with the host ECG, we found that grafts in uninjured hearts have consistent 1:1 host–graft coupling. Grafts in injured hearts are more heterogeneous and typically include both coupled and uncoupled regions. Thus, human myocardial grafts meet physiological criteria for true heart regeneration, providing support for the continued development of hESC-based cardiac therapies for both mechanical and electrical repair.

Overexpression of the Homo sapiens LYR motif containing 1 (LYRM1) causes mitochondrial dysfunction and induces insulin resistance in 3T3-L1 adipocytes. α-Lipoic acid (α-LA), a dithiol compound with antioxidant properties, improves glucose transport and utilization in 3T3-L1 adipocytes. The aim of this study was to investigate the direct effects of α-LA on reactive oxygen species (ROS) production and insulin sensitivity in LYRM1 overexpressing 3T3-L1 adipocytes and to explore the underlying mechanism. Pretreatment with α-LA significantly increased both basal and insulin-stimulated glucose uptake and insulin-stimulated GLUT4 translocation, while intracellular ROS levels in LYRM1 overexpressing 3T3-L1 adipocytes were decreased. These changes were accompanied by a marked upregulation in expression of insulin-stimulated tyrosine phosphorylation of IRS-1 and serine phosphorylation of Akt following treatment with α-LA. These results indicated that α-LA protects 3T3-L1 adipocytes from LYRM1-induced insulin resistance partially via its capacity to restore mitochondrial function and/or increase phosphorylation of IRS-1 and Akt.

Mountain sickness (MS) occurs among humans visiting or inhabiting high altitude environments. We conducted genetic analyses of the AKT3, ANGPTL4, eNOS3 and VEGFA genes in lowland (Han) and highland (Tibetan) Chinese. Ten single nucleotide polymorphisms (SNPs) were evaluated in Han and Tibetan patients with acute (A) and chronic (C) MS. We compared 74 patients with AMS to 79 Han unaffected with MS, as well as 48 CMS patients to 31 unaffected Tibetans. The ten SNPs studied are AKT3 (rs4590656, rs2291409), ANGPTL4 (rs1044250), eNOS3 (rs1007311, rs1799983) and VEGFA (rs79469752, rs13207351, rs28357093, rs1570360, rs3025039). Direct sequencing was used to identify individual genotypes for these SNPs. Hemoglobin (Hb), hematocrit (Hct), and red blood cell count (RBC) were found to be significantly associated with the AKT3 SNP (rs4590656), Hb was found to be associated with the eNOS3 SNP (rs1007311), and RBC was found to be significantly associated with the VEGFA SNP (rs1570360) in Tibetan patients with CMS. CMS patients were found to diverge significantly for both eNOS3 SNPs as measured by genetic distance (0.042, 0.047) and for the VEGFA SNP (rs28357093) with a genetic distance of 0.078 compared to their Tibetan control group. Heart rate (HR) was found to be significantly associated with the eNOS3 SNP (rs1799983) and arterial oxygen saturation of hemoglobin (SaO2) was found to be significantly associated with the VEGFA SNPs (rs13207351, rs1570360) in Han patients with AMS. The Han and Tibetan control groups were found to diverge significantly for the ANGPTL4 SNP and VEGFA SNP (rs28357093), as measured by genetic distances of 0.049 and 0.073, respectively. Seven of the SNPs from non-coding regions are found in the transcriptional factor response elements and their possible role in gene regulation was evaluated with regard to MS. AMS and CMS were found to be significantly associated with the four genes compared to their Han and Tibetan control groups, respectively, indicating that these nucleotide alterations have a physiological effect for the development of high altitude sickness.

Obesity is a multifactorial disease resulting from interactions between susceptibility genes, psychosocial, and environmental factors. However, it is becoming evident that interindividual differences in obesity susceptibility depend also on epigenetic factors, although the mechanisms have not been fully elucidated. We have undertaken a genome-wide analysis of DNA methylation of human preadipocytes and mature adipocytes to examine the differences in methylation between them. We found hypomethylation occurring in 2,701 genes and hypermethylation in 1,070 genes after differentiation. Meanwhile, Gene Ontology analysis and Ingenuity Pathway Analysis showed many significant gene functions and pathways with altered methylation status after adipocyte differentiation. In addition, Signal-Net analysis showed that tumor necrosis factor-α, mitogen-activated protein kinase, and interleukin-8 were important to the formation of this network. Our results suggest that DNA methylation mechanisms may be involved in regulating the differentiation process of human preadipocytes.