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Spexin is a novel hormone involved in obesity and diabetes while its biofunctional significance in lipid metabolism is still to be comprehended. Global metabolomic analysis in the present study revealed multiple metabolic pathways altered by spexin intraperitoneal (i.p.) injection in rat serum, which are highlighted by the changes in several bile acid metabolites. In rats, spexin (300 μg/kg) could dramatically reduce hepatic and circulating total bile acids (TBA) level compared with the controls. Correspondingly, treatment with spexin by i.p. injection for 28 days led to significant decrease in serum TBA and gallbladder weight in C57BL/6J mice. In enterohepatic circulation system, spexin effectively reduced TBA levels in mouse liver and gallbladder but not the intestine. Hepatic cholesterol 7α-hydroxylase 1 (CYP7A1) expression, unsurprisingly, was suppressed by spexin injection. Both GALR2 and GALR3 antagonists reversed the inhibitory effects of spexin on concentrations of serum TBA and 7 α-hydroxy-4-cholesten-3-one (C4), and hepatic CYP7A1 expression. Finally, negative correlations were observed between serum spexin and total cholesterol (TC), total bile acid (TBA), tauro-chenodeoxycholate (TCDCA), as well as glycochenodeoxycholate (GCDCA) in 91 healthy volunteers. These findings illuminate the intrinsic importance of spexin in the regulation of bile acid synthesis and metabolism.

Recent studies indicate that mitochondrial pathways of apoptosis are potential chemotherapeutic target for the treatment of esophageal cancer. Azoxystrobin (AZOX), a methoxyacrylate derived from the naturally occurring strobilurins, is a known fungicide acting as a ubiquinol oxidation (Qo) inhibitor of mitochondrial respiratory complex III. In this study, the effects of AZOX on human esophageal squamous cell carcinoma KYSE-150 cells were examined and the underlying mechanisms were investigated. AZOX exhibited inhibitory effects on the proliferation of KYSE-150 cells with inhibitory concentration 50% (IC50) of 2.42 μg/ml by 48 h treatment. Flow cytometry assessment revealed that the inhibitory effect of AZOX on KYSE-150 cell proliferation occurred with cell cycle arrest at S phase and increased cell apoptosis in time-dependent and dose-dependent manners. Cleaved poly ADP ribose polymerase (PARP), caspase-3 and caspase-9 were increased significantly by AZOX. It is worth noted that the Bcl-2/Bax ratios were decreased because of the down-regulated Bcl-2 and up-regulated Bax expression level. Meanwhile, the cytochrome c release was increased by AZOX in KYSE-150 cells. AZOX-induced cytochrome c expression and caspase-3 activation was significantly blocked by Bax Channel Blocker. Intragastric administration of AZOX effectively decreased the tumor size generated by subcutaneous inoculation of KYSE-150 cells in nude mice. Consistently, decreased Bcl-2 expression, increased cytochrome c and PARP level, and activated caspase-3 and caspase-9 were observed in the tumor samples. These results indicate that AZOX can effectively induce esophageal cancer cell apoptosis through the mitochondrial pathways of apoptosis, suggesting AZOX or its derivatives may be developed as potential chemotherapeutic agents for the treatment of esophageal cancer.

Cantharidin and its analogs are potent serine/threonine protein phosphatase inhibitors with rare reports on inhibiting expression of Hepatitis B virus (HBV) DNA. Five imide cantharidin derivatives were synthesized, and their properties were studied. The inhibition efficiency was determined, and preliminary studies on the structure-activity relationships were conducted. The results indicated that the compounds characterized by low Log P values and the cantharidin moieties containing nitrogen exhibited low cytotoxicity and helped inhibit the expression of HBV DNA. Compound 2 and the non-cytotoxic compound 3 significantly inhibited the expression of HBV DNA. The IC50 values recorded for both compounds were 2.0±1.2 and 19.2±2.0 nM, respectively. [ABSTRACT FROM AUTHOR]

Magnolol is a lignan with anti-inflammatory activity identified in Magnolia officinalis. Ulcerative colitis (UC), one of the types of inflammatory bowel disease (IBD), is a disease that causes inflammation and ulcers in the colon. To investigate the effect of magnolol in dextran sulfate sodium (DSS)-induced experimental UC model, male C57 mice were treated with 2% DSS drinking water for 5 consecutive days followed by intragastric administration with magnolol (5, 10 and 15 mg/kg) daily for 7 days. The results showed that magnolol significantly attenuated disease activity index, inhibited colonic shortening, reduced colonic lesions and suppressed myeloperoxidase (MPO) activity. Moreover, colonic pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β) induced by colitis were dramatically decreased by magnolol. To further unveil the metabolic signatures upon magnolol treatment, mass spectrometry-based metabolomic analysis of the small molecular metabolites in mice serum were performed. Compared with controls, abnormality of serum metabolic phenotypes in DSS-treated mice were effectively reversed by different doses of magnolol. In particular, magnolol treatment effectively elevated the serum levels of tryptophan metabolites including kynurenic acid (KA), 5-hydroxyindoleacetic acid, indoleacetic acid (IAA), indolelactic acid and indoxylsulfuric acid, which are potential aryl hydrocarbon receptor (AHR) ligands to impact colitis. These findings suggest that magnolol exerts anti-inflammatory effect on DSS-induced colitis and its underlying mechanisms are associated with the restoring of tryptophan metabolites that inhibit the colonic inflammation.

The development of two novel bifunctional amine-thiourea organocatalysts both of which bear central and axial chiral elements to promote the enantioselective Michael reaction between 1,3-dicarbonyl compounds and nitro olefins is reported. The bifunctional amine-thiourea organocatalysts might have potential use for the design of novel chiral organocatalysts.

Chlorovinylcobalamin could be generated by reaction of cob(I)alamin with chloroacetylene, a compound detected as an intermediate in the B12-catalyzed dechlorination of perchloroethylene. Return of chlorinated vinylcobalamins to the active form of the catalyst could be achieved through reductive dealkylation promoted by col(I)alamin.

An interesting methodology that allows a simple optical (colorimetric or fluorometric) detection of iodide is developed. The method is based on conformational modifications of the conjugated backbone of cationic poly(3-alkoxy-4-methylthiophene) upon binding of iodide anions.

A stereoselective synthesis of alhpa-N-glycopeptide linkage from readily available 1-azidoglucopyranosyl derivatives is presented. The synthesis employs the readily available glycosyl azides as a starting material.

A synthetic approach for the direct, liquid-phase sulfonation of methane with SO2 is demonstrated. Twenty-two percent conversion of SO2 to methanesulfonic acid was achieved after 26 h of reaction, under the best reaction conditions.

A novel chiral diphosphine ligands with spiro biindane as a new chiral scaffold is developed, which is highly effective for the asymmetric hydrogenation of ketones. The extremely high activity and enantioselectivity of the ruthenium complexes for the hydrogenation of a variety of prochiral ketones indicate a good potential for wide application of spiro diphosphine ligands.

Abstract Background Rapid stratification and appropriate treatment on admission are critical to saving lives of patients with acute pulmonary embolism (PE). None of the clinical prediction tools perform well when applied to all patients with acute PE. It may be important to integrate respiratory features into the 2014 European Society of Cardiology model. First, we aimed to assess the relationship between the arterial partial pressure of oxygen/fraction of inspired oxygen (PaO2/FIO2) ratio and in-hospital mortality, determine the optimal cutoff value of PaO2/FIO2, and determine if this value, which is quick and easy to obtain on admission, is a predictor of in-hospital mortality in this population. Second, we aimed to evaluate the potential additional determinants including laboratory parameters that may affect the in-hospital mortality. We hypothesized that the PaO2/FiO2 ratio would be a clinical prediction tool for in-hospital mortality in patients with acute PE. Methods A prospective single-center observational cohort study was conducted in Beijing Hospital from January 2010 to November 2017. Arterial blood gas analysis data captured on admission, clinical characteristics, risk factors, laboratory data, imaging findings, and in-hospital mortality were compared between survivors and non-survivors. The area under the receiver operating characteristic curve (AUC) for in-hospital mortality based on the PaO2/FiO2 value was determined, and the association between the parameters and in-hospital mortality was analyzed by using logistic regression analysis. Results Body mass index, history of cancer, PaO2/FiO2 value, pulse rate, cardiac troponin I level, lactate dehydrogenase level, white blood cell count, D-dimer level, and risk stratification measurements differed between survivors and non-survivors. The optimal cutoff value of PaO2/FiO2 for predicting mortality was 265 (AUC = 0.765, P

The first catalytic asymmetric [2 + 2] cycloaddition of oxabicyclic alkenes and terminal alkynes has been developed. This iridium-catalyzed enantioselective [2 + 2] cycloaddition allows the formation of four stereocenters in a single step with excellent enantioselectivity (94→99% ee). [ABSTRACT FROM AUTHOR]