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C2+ hydrocarbons, especially C2+ olefins, as important basic chemical raw materials, mainly come from petroleum cracking. With the increasing scarcity of petroleum resources, the search for new olefins production routes has become the focus of research, and the production of olefins by the oxidative coupling of methane (OCM) process has attracted extensive attention. The OCM route is an important alternative to the production of olefins from petroleum resources and is also an important direction for the development of efficient and clean utilization of natural gas. In this paper, the mechanism, catalysts, and other key factors for the production of olefins by methane oxidative coupling are reviewed. The mechanism of OCM, including the reaction pathway and the formation of intermediate products, is introduced. Then, commonly used catalysts, such as alkali metal/alkaline earth metal oxides, rare earth metal oxides, composite metal oxides with special structures, and classical catalysts Mn/Na2WO4/SiO2, and their mechanisms of action in the reaction are discussed. In addition, the application of chemical looping oxidative coupling of methane (CLOCM) in olefin production is also investigated, which is a promising alternative way due to the high selectivity of olefins and the low cost of catalysts owing to the excellent performance of the catalyst recycling. These studies will help to further understand the mechanism of OCM for olefin production and provide guidance and support for applications in related fields. [ABSTRACT FROM AUTHOR]

Background: The gut microbiome plays a pivotal role in the progression of sepsis. However, the specific mechanism of gut microbiota and its metabolites involved in the process of sepsis remains elusive, which limits its translational application. Method: In this study, we used a combination of the microbiome and untargeted metabolomics to analyze stool samples from patients with sepsis enrolled at admission, then microbiota, metabolites, and potential signaling pathways that might play important roles in disease outcome were screened out. Finally, the above results were validated by the microbiome and transcriptomics analysis in an animal model of sepsis. Results: Patients with sepsis showed destruction of symbiotic flora and elevated abundance of Enterococcus, which were validated in animal experiments. Additionally, patients with a high burden of Bacteroides, especially B. vulgatus, had higher Acute Physiology and Chronic Health Evaluation II scores and longer stays in the intensive care unit. The intestinal transcriptome in CLP rats illustrated that Enterococcus and Bacteroides had divergent profiles of correlation with differentially expressed genes, indicating distinctly different roles for these bacteria in sepsis. Furthermore, patients with sepsis exhibited disturbances in gut amino acid metabolism compared with healthy controls; namely, tryptophan metabolism was tightly related to an altered microbiota and the severity of sepsis. Conclusion: Alterations in microbial and metabolic features in the gut corresponded with the progression of sepsis. Our findings may help to predict the clinical outcome of patients in the early stage of sepsis and provide a translational basis for exploring new therapies. [ABSTRACT FROM AUTHOR]

Background: The gut microbiome plays a pivotal role in the progression of sepsis. However, the specific mechanism of gut microbiota and its metabolites involved in the process of sepsis remains elusive, which limits its translational application. Method: In this study, we used a combination of the microbiome and untargeted metabolomics to analyze stool samples from patients with sepsis enrolled at admission, then microbiota, metabolites, and potential signaling pathways that might play important roles in disease outcome were screened out. Finally, the above results were validated by the microbiome and transcriptomics analysis in an animal model of sepsis. Results: Patients with sepsis showed destruction of symbiotic flora and elevated abundance of Enterococcus, which were validated in animal experiments. Additionally, patients with a high burden of Bacteroides, especially B. vulgatus, had higher Acute Physiology and Chronic Health Evaluation II scores and longer stays in the intensive care unit. The intestinal transcriptome in CLP rats illustrated that Enterococcus and Bacteroides had divergent profiles of correlation with differentially expressed genes, indicating distinctly different roles for these bacteria in sepsis. Furthermore, patients with sepsis exhibited disturbances in gut amino acid metabolism compared with healthy controls; namely, tryptophan metabolism was tightly related to an altered microbiota and the severity of sepsis. Conclusion: Alterations in microbial and metabolic features in the gut corresponded with the progression of sepsis. Our findings may help to predict the clinical outcome of patients in the early stage of sepsis and provide a translational basis for exploring new therapies. [ABSTRACT FROM AUTHOR]

The core-shell nanoparticles of Au@TiO2 were synthesised via a simple and flexible hydrothermal route. The structure and properties were characterised by X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray spectroscopy, ultraviolet/visible diffuse reflectance spectra, photoluminescence spectra and Raman spectra. The photocatalytic activity and the photoelectrochemical behaviours were investigated. Compared to TiO2, Au@TiO2 exhibits superior photocatalytic activity and photoelectrochemical property. The enhanced properties of Au@TiO2 attributed to the Au core as electron trap to promote the separation of photogenerated charge carriers in the photocatalytic process, which was also confirmed by the results of electrochemical impedance spectra and photoluminescence. [ABSTRACT FROM AUTHOR]

In this work, g-C3N4/melem nanorods hybrids were synthesized via a rapid cooling process with H2SO4-assisted treatments of bulk g-C3N4. The results show that post treatment of pristine g-C3N4 using concentrated H2SO4 can produce a hybrid crystal structure containing both melem and g-C3N4. The melem nanorods were formed based on H2SO4 exfoliation, regrowth process and nanoplates roll-up mechanism through a rapid cooling process. The g-C3N4/melem nanorods hybrids exhibited efficient degradation of methyl orange and the efficiency was nearly 100% in 80 min, which presented much better than bulk g-C3N4 (giving a degradation efficiency of 67% in 80 min). The enhanced photocatalytic performance of g-C3N4/melem nanorods hybrids mainly originates from the synergistic effect of g-C3N4 and melem, which the g-C3N4/melem hybrids can improving the efficiency of photogenerated charge separation of g-C3N4. This study contributes towards an effective strategy for optimizing the crystalline structure and nanostructure of g-C3N4/melem hybrids to enhanced g-C3N4 photodegradation activity. [ABSTRACT FROM AUTHOR]

Objectives. Untreated acromegaly is a nature model for unveiling the diabetogenic effects of GH. CGMS can uncover more glucose profile of acromegaly. This study aimed to evaluate the insulin resistance (IR), β-cell function, and glycemic spectrum of patients with newly diagnosed acromegaly with normal glucose tolerance (NGT). Methods. This study was conducted in Huashan Hospital from January 2015 to February 2019. Eight newly diagnosed acromegalic patients without history of diabetes and eight age- and gender-matched healthy subjects were enrolled. All participants underwent oral glucose tolerance test (OGTT) and 72 h continuous glucose monitoring (CGM). Parameters on β-cell function and IR were calculated. Mean blood glucose (MBG) in 24 hours was adopted for the evaluation of the glycemic level, and standard deviation of blood glucose (SDBG) and mean amplitude of glycemic excursion (MAGE) were used for glucose fluctuation. Results. HbA1c in the acromegaly group was significantly higher than in the control. During OGTT, glucose peaked at 60 min in acromegaly and at 30 min in controls. After glucose load, the acromegaly group had significantly higher insulin levels than controls, especially in 120 min and 180 min. Both insulin sensitivity index and disposal index after glucose load of acromegaly were significantly lower than those of controls. Moreover, acromegalic subjects had significantly higher MBG than controls. Conclusions. The newly diagnosed acromegalic patients with NGT were characterized by IR and impaired β-cell function after glucose load. CGM showed that MBG of NGT acromegaly patients was higher than that of normal people. [ABSTRACT FROM AUTHOR]

Ischemia reperfusion injury (IRI) is a critical problem in liver transplantation that can lead to life-threatening complications and substantially limit the utilization of livers for transplantation. However, because there are no early diagnostics available, fulminant injury may only become evident post-transplant. Mitochondria play a central role in IRI and are an ideal diagnostic target. During ischemia, changes in the mitochondrial redox state form the first link in the chain of events that lead to IRI. In this study we used resonance Raman spectroscopy to provide a rapid, non-invasive, and label-free diagnostic for quantification of the hepatic mitochondrial redox status. We show this diagnostic can be used to significantly distinguish transplantable versus non-transplantable ischemically injured rat livers during oxygenated machine perfusion and demonstrate spatial differences in the response of mitochondrial redox to ischemia reperfusion. This novel diagnostic may be used in the future to predict the viability of human livers for transplantation and as a tool to better understand the mechanisms of hepatic IRI. [ABSTRACT FROM AUTHOR]

Aims. To investigate the association between mean plasma glucose and inhospital death proportion. Methods. We retrospectively collected 162,169 inpatient data in Huashan Hospital from January 2012 to December 2015. Mean plasma glucose was calculated and considered as the average glycemia control during hospitalization. Patients were stratified into six groups according to mean plasma glucose. Nonlinear regression was performed to determine the associations between mean plasma glucose and inhospital death proportion, medical cost, and length of stay. Multivariate logistic regressions were performed to evaluate the relationship of mean plasma glucose and outcomes controlling for confounders including age, gender, and others. Subgroup analyses were performed on basis of whether they were surgical patients, ICU patients, patients with diabetes, or others. Results. Of the 162,169 hospitalized participants, 53.32% were male and 989 died during hospitalization. Nonlinear regression showed there were positive and significant associations between mean plasma glucose and death proportion, medical cost, and length of stay (P < 0.001 for all). Multivariate logistic regressions showed that, compared with group B, a statistically significant association between mean plasma glucose and predicted outcome was apparent, with the odds ratios (95% confidence interval) of 5.79 (3.51–9.55), 2.85 (2.40–3.38), 6.29 (5.24–7.54), 9.34 (7.51–11.62), and 23.52 (16.64–33.26), for group A, group C, group D, group E, and group F, respectively. There was a U-shaped association between mean plasma glucose and death proportion. Subgroup analyses showed similar associations between mean plasma glucose and death proportion, medical cost, and length of stay as in the whole sample. Conclusions. There was a U-curve association between mean plasma glucose with inhospital death proportion. Mean plasma glucose was associated positively with medical cost and length of stay. [ABSTRACT FROM AUTHOR]

Purpose: We sought to determine the impact of levosimendan on mortality following cardiac surgery based on large-scale randomized controlled trials (RCTs).Methods: We searched PubMed, Web of Science, Cochrane databases, and ClinicalTrials.gov for RCTs published up to December 2017, on levosimendan for patients undergoing cardiac surgery.Results: A total of 25 RCTs enrolling 2960 patients met the inclusion criteria; data from 15 placebo-controlled randomized trials were included for meta-analysis. Pooled analysis showed that the all-cause mortality rate was 6.4% (71 of 1106) in the levosimendan group and 8.4% (93 of 1108) in the placebo group (odds ratio [OR], 0.76; 95% confidence interval [CI], 0.55-1.04; P = 0.09). There were no significant differences between the two groups in the rates of myocardial infarction (OR: 0.91; 95% CI, 0.68-1.21; P = 0.52), serious adverse events (OR: 0.84; 95% CI, 0.66-1.07; P = 0.17), hypotension (OR: 1.69; 95% CI, 0.94-3.03; P = 0.08), and low cardiac output syndrome (OR: 0.47; 95% CI, 0.22-1.02; P = 0.05).Conclusion: Levosimendan did not result in a reduction in mortality in adult cardiac surgery patients. Well designed, adequately powered, multicenter trials are necessary to determine the role of levosimendan in adult cardiac surgery. [ABSTRACT FROM AUTHOR]

Imprinting is a biological process where a young animal acquires several of its behavioural characteristics from its parent and then follows them around and is called filial imprinting. However, imprinting can implicitly be inside the materials that possess a suitable affinity to integrate themselves with the surrounding liquid environment. In this research, an example of imprinting in molybdenum disulfide (MoS2) nanosheets was demonstrated. The as-prepared MoS2 containing a polar edge and low-polar plane faces on its flower-like morphology give it an imprinting ability to adhere to water or n-hexane. Therefore, imprinted MoS2 tends to retain the phase of the imprinting solvent, which is called solvent identification. More interestingly, imprinted MoS2 can in addition fulfill a highly efficient heterophasic extraction of rhodamine B (RhB) from water to n-hexane or lauric acid from n-hexane to water in seconds. At the same time, imprinted MoS2 solvent identification exhibits rapid self-separation after shaking, which avoids tedious centrifugation and filtration in a separation-purification process and makes it more convenient. [ABSTRACT FROM AUTHOR]

We have characterized a novel 21 amino acid-peptide derived from Antrum Mucosal Protein (AMP)-18 that mediates growth promotion of cultured normal epithelial cells and mitigates radiation-induced oral mucositis in animal models, while suppressing in vitro function of cancer cells. The objective of this study was to evaluate these dual potential therapeutic effects of AMP peptide in a clinically relevant animal model of head and neck cancer (HNC) by simultaneously assessing its effect on tumor growth and radiation-induced oral mucositis in an orthotopic model of HNC. Bioluminescent SCC-25 HNC cells were injected into the anterior tongue and tumors that formed were then subjected to focal radiation treatment. Tumor size was assessed using an in vivo imaging system, and the extent of oral mucositis was compared between animals treated with AMP peptide or vehicle (controls). Synergism between AMP peptide and radiation therapy was suggested by the finding that tumors in the AMP peptide/radiation therapy cohort demonstrated inhibited growth vs. radiation therapy-only treated tumors, while AMP peptide-treatment delayed the onset and reduced the severity of radiation therapy-induced oral mucositis. A differential effect on apoptosis appears to be one mechanism by which AMP-18 can stimulate growth and repair of injured mucosal epithelial cells while inhibiting proliferation of HNC cells. RNA microarray analysis identified pathways that are differentially targeted by AMP-18 in HNC vs. nontransformed cells. These observations confirm the notion that normal cells and tumor cells may respond differently to common biological stimuli, and that leveraging this finding in the case of AMP-18 may provide a clinically relevant opportunity. [ABSTRACT FROM AUTHOR]

Aspirin is a widely used medication and has become a cornerstone for treating cardiovascular disease. Aspirin can significantly reduce the incidence of cardiovascular ischemic events, recurrence and mortality, thereby improving the long-term prognosis of patients. However, there has been a staggering increase in the volume of literature addressing the issue of so-called "aspirin resistance" in recent years, and for some patients, it is difficult to avoid adverse reactions to aspirin. In this review, we present both the historical aspects of aspirin use and contemporary developments in its clinical use. [ABSTRACT FROM AUTHOR]

Dysregulated homeostasis of epithelial cells resulting in disruption of mucosal barrier function is an important pathogenic mechanism in inflammatory bowel diseases (IBD). We have characterized a novel gastric protein, Antrum Mucosal Protein (AMP)-18, that has pleiotropic properties; it is mitogenic, anti-apoptotic and can stimulate formation of tight junctions. A 21-mer synthetic peptide derived from AMP-18 exhibits the same biological functions as the full-length protein and is an effective therapeutic agent in mouse models of IBD. In this study we set out to characterize therapeutic mechanisms and identify molecular targets by which AMP-18 maintains and restores disrupted epithelial homeostasis in cultured intestinal epithelial cells and a mouse model of IBD. Tumor necrosis factor (TNF)-α, a pro-inflammatory cytokine known to mediate gastrointestinal (GI) mucosal injury in IBD, was used to induce intestinal epithelial cell injury, and study the effects of AMP-18 on apoptosis and the cell cycle. An apoptosis array used to search for targets of AMP-18 in cells exposed to TNF-α identified the cyclin-dependent kinase inhibitor p21WAF1/CIP1. Treatment with AMP-18 blunted increases in p21 expression and apoptosis, while reversing disturbed cell cycle kinetics induced by TNF-α. AMP-18 appears to act through PI3K/AKT pathways to increase p21 phosphorylation, thereby reducing its nuclear accumulation to overcome the antiproliferative effects of TNF-α. In vitamin D receptor-deficient mice with TNBS-induced IBD, the observed increase in p21 expression in colonic epithelial cells was suppressed by treatment with AMP peptide. The results indicate that AMP-18 can maintain and/or restore the homeostatic balance between proliferation and apoptosis in intestinal epithelial cells to protect and repair mucosal barrier homeostasis and function, suggesting a therapeutic role in IBD. [ABSTRACT FROM AUTHOR]

J. Neurochem. (2011) 119, 1041-1051. Abstract Inflammation is a key factor in a number of neurodegenerative diseases including systemic lupus erythematosus. The complement system is an important mechanism in initiating and amplifying inflammation. Our recent studies demonstrate that C5a, a protein fragment generated during complement activation could alter the blood-brain barrier integrity, and thereby disturb the brain microenvironment. To understand the mechanism by which this occurs, we examined the effects of C5a on apoptosis, translocation of nuclear factor-κB (NF-κb) and the expression of Iκbα, MAPK, CREB and TJ protein, zona occludens (ZO-1) in mouse brain endothelial cells. Apoptosis was examined by DNA laddering and caspase 3 activity and the distribution of the ZO-1 and the p65 subunit of NF-κB were determined by immunofluorescence. Inhibition of CD88 reduced translocation of NF-κb into the nucleus, altered ZO-1 at the interfaces of neighboring cells, decreased caspase 3 activity and prevented apoptosis in these cells. Our results indicate that signaling through CD88 regulates the blood-brain barrier in a NF-κb-dependent manner. These studies suggest that the C5a receptor, CD88 is a promising therapeutic target that will reduce NF-κb-signaling cascades in inflammatory settings. [ABSTRACT FROM AUTHOR]

The interaction between palladium(II)-chlorpromazine hydrochloride and sodium tungstate was investigated by ultraviolet-visible absorption, resonance Rayleigh scattering (RRS), second-order scattering (SOS) and frequency doubling scattering (FDS) spectroscopy. In pH 5.3 Britton-Robinson (BR) buffer medium, chlorpromazine hydrochloride (CPZ) reacted with Pd(II) to form 2:1 cationic chelate, which further reacted with NaWO to form a 1:1 ternary ion-association complex ([Pd(CPZ)]·WO). As a result, the signal intensities of RRS, SOS and FDS were enhanced greatly, and the enhancements of scattering were proportional to the CPZ concentration in a certain range. Their maximum wavelengths were located at 310 nm, 570 nm and 391 nm, respectively and the detection limits (3 σ) were 1.6 ng/mL (RRS method), 3.2 ng/mL (SOS method) and 5.6 ng/mL (FDS method). The optimum reaction conditions, the influences of coexisting substances and analytical application were mainly investigated by RRS method due to its highest sensitivity. A highly sensitive, simple, rapid and new method had been proposed to determine CPZ in the pharmaceutical form and residue of CPZ in pork. In addition, the Gibbs free energy change (δ G) of ion-association reaction was computed by using B3LYP/3-21g*/LanL2dz method. The formation of ion-association and the reasons for the enhancement of RRS were also discussed. [ABSTRACT FROM AUTHOR]

In pH 1.0 acidic medium, 12-Tungstophosphoric acid (TP) reacted with meclofenoxate (MFX) to form an ion-associate complex, which resulted in a significant enhancement of the resonance Rayleigh scattering (RRS) intensity. The RRS intensity at the maximum scattering peak of 374 nm was linear to the concentration of MFX in the range of 0.2-12.0 μg mL-1. Therefore, a novel method for the determination of MFX by RRS method coupled with flow injection analysis (FIA) technique was developed. The method has highly sensitivity and the detection limit (3σ) was 5.6 ng mL-1. The present method was applied to the determination of MFX in pharmaceutical preparations and the results agreed well with those provided by the pharmacopeia. The average recovery of standard addition in capsules was 97.0-103.1%. The proposed method exhibited the satisfactory reproducibility with a relative standard derivation (R.S.D.) of 3.7% for 9 successive determinations of 4.0 μg mL-1 MFX. The maximal sample throughput in the optimized system was 48 h-1. In addition, the optimum experiment condition, the effect of coexisting substance, and influence of FIA variables were investigated in the paper. [ABSTRACT FROM AUTHOR]

Both the mitogen-activated protein kinase (MAPK) phosphatases MKP-1 and MKP-2 exert important feedback control of MAPK-mediated signaling events. The function of MKP-1 and MKP-2 is regulated via complex mechanisms, ranging from increased transcription of the MKP-1 and MKP-2 genes to post-translational catalytic activation of MKP-1 and MKP-2 proteins upon binding to their substrate MAPKs. In addition, MKP-1 stability increases upon ERK-dependent phosphorylation of two serine residues in its C-terminus. The C-terminal regions of MKP-1 and MKP-2, but not those of other MKPs, are homologous. To investigate the role of this domain, we have deleted the C-terminal tails from MKP-1 and MKP-2 and examined the effect of these deletions on their enzymatic activity. C-terminally truncated MKP-1 and MKP-2 exhibited, both in vivo and in vitro, substantially greater phosphatase activity towards their substrate MAPKs than did the full-length counterparts. However, C-terminal truncations did not significantly change either their substrate affinity, or their substrate-mediated catalytic activation. Basal phosphatase activity of the truncated proteins was also significantly higher than that of the wild-type counterparts. Collectively, these results suggest that the C-terminal domain may potentially play a role in the regulation of MKP-1 and MKP-2. [ABSTRACT FROM AUTHOR]

The formation and decomposition of gas hydrates in nanoscale sediments can simulate the accumulation and mining process of hydrates. This paper investigates the Raman spectra of water confined inside the nanoscale pores of silica gel, the decomposition characterizations of methane hydrate that formed from the pore water, and the intrinsic relationship between them. The results show that pore water has stronger hydrogen bonds between the pore water molecules at both 293 K and 223 K. The structure of pore water is conducive to the nucleation of gas hydrate. Below 273.15 K, the decomposition of methane hydrate formed from pore water was investigated at atmospheric pressure and at a constant volume vessel. We show that the decomposition of methane hydrate is accompanied by a reformation of the hydrate phase: The lower the decomposition temperature, the more times the reformation behavior occurs. The higher pre-decomposition pressure that the silica gel is under before decomposition is more favorable to reformation. Thus, reformation is the main factor in methane hydrate decomposition in nanoscale pores below 273.15 K and is attributed to the structure of pore water. Our results provide experimental data for exploring the control mechanism of hydrate accumulation and mining. [ABSTRACT FROM AUTHOR]