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A selective ultra‐high performance liquid chromatography tandem mass spectrometry cubed (UHPLC/MS3) assay for simultaneous determination of methotrexate (MTX) and 7‐hydroxy‐methotrexate (7‐OH‐MTX) in human plasma was developed and validated. After protein precipitation with methanol, chromatographic separation of MTX, MTX‐d3, and 7‐OH‐MTX was performed on a Waters AcQuity UPLC‐BEH column (2.1 × 50 mm I.D., 1.7 µm) with gradient elution. MRM3 transition was used for the detection of MTX (m/z 455.2→308.0→175.1) and 7‐OH‐MTX (m/z 471.3→191.0→148.1). The linear range of UHPLC/MS3 assay for the determination of MTX and 7‐OH‐MTX was 0.5–300 ng/mL (R2 ≥ 0.99) and 5–1500 ng/mL (R2 ≥ 0.99), respectively. The enhanced selectivity and sensitivity are the novelties of the developed UHPLC/MS3 assay. The analytical method was successfully applied to simultaneous determination of MTX and its major metabolite 7‐OH‐MTX in real human plasma samples. [ABSTRACT FROM AUTHOR]

Background: Citrate anticoagulation is an important anticoagulation method in hemodialysis (HD) but cannot completely prevent the occurrence of coagulation in the extracorporeal circulation (ECC) circuit, and the clinical coagulation status can significantly affect the effect of citrate anticoagulation. In this study, the relationships between clinical coagulation status indicators and coagulation in the ECC circuit in HD patients receiving individualized citrate anticoagulant were studied to explore indicators that may predict coagulation in the ECC circuit. Methods: This study was a single‐center, retrospective clinical study, and clinical data and laboratory tests related to the coagulation status of HD patients receiving individualized regional citrate anticoagulation (RCA) were collected. The relationships between indicators commonly used in clinical practice to evaluate clinical coagulation status and coagulation in the ECC circuit were statistically analyzed to find indicators that can predict the occurrence of coagulation in the ECC circuit. Results: The individualized RCA had a good anticoagulation effect, and the actual citrate infusion rate in nearly 80% of the patients was within ±10% of the theoretical infusion rate. The combined diseases or conditions that affect the coagulation status in vivo may increase the incidence of coagulation in the ECC circuit. The clinical D‐dimer level is an independent risk factor that affects and can predict coagulation in the ECC circuit, with a cutoff value of 2.03 mg/L, sensitivity of 59%, and specificity of 78%. Conclusion: Individualized RCA can meet the needs of most HD treatments. Abnormal coagulation status in HD patients may increase the incidence of coagulation in the ECC circuit during individualized RCA for HD, and the D‐dimer level can predict the occurrence of coagulation in the ECC circuit during this treatment. [ABSTRACT FROM AUTHOR]

A type of high‐efficiency boiling heat transfer (BHT) interfaces based on superhydrophilic copper microcavity and nanocone (CMN) composite structure are reported. In principle, these microcavities are efficient nucleation sites, facilitating decreasing surface superheat required for onset of nucleation boiling (ONB) and enhancing heat transfer coefficient (HTC); discrete nanotips facilitate the departure of boiling bubbles at smaller scale; shallow microcavities with depth of a few micrometers can avoid excess interface thermal resistance; and the superwetting effect of structure itself helps improve critical heat flux (CHF). Through exploring morphology, wettability, boiling mass and heat transfer properties of CMN structures varied with growth time, an optimal interface is obtained with 142% enhancement in the maximum HTC, 64% enhancement in CHF, and 33% decrease in the ONB superheat as compared to the flat copper surface. Meanwhile, combined experiments and theoretical analyses also clarify why the in situ growth of CMN structures on the copper surface can effectively enhance BHT and why the BHT enhancement effects become worse as the growth time of CMN structure increases. This work not only widens the application scope of superwetting surfaces but offers new insight how to rationally design superhydrophilic micro‐ and nanostructures so as to achieve more efficient BHT. [ABSTRACT FROM AUTHOR]

Palladium‐ and rhodium‐catalyzed selective reactions of 2H‐azirines and N‐(acyloxy)amides leading to α‐amino oxime esters were described. The regioselectivities of the reactions are catalyst‐controlled, and two different α‐amino oxime esters were selectively obtained in high yields. These reactions involved the construction of new N–O and C–N bonds, which are characterized by 100 % atom economy, good to excellent yields, and mild reaction conditions. Palladium‐ and rhodium‐catalyzed selective reactions of 2H‐azirines and N‐(acyloxy)amides leading to α‐amino oxime esters were described. The regioselectivity is catalyst‐controlled, and two different α‐amino oxime esters were chemoselectively obtained in high yields. [ABSTRACT FROM AUTHOR]

Abstract: A copper‐mediated one‐pot sequential reaction of terminal alkynes, azides, and propargylic carbonates is reported. The three component reaction occurs readily at room temperature to afford a 5‐allenyl‐1,2,3‐triazoles in high yields, providing a straightforward approach to 1,3,5‐trisubstituted triazoles using easily available Cu(I) reagent. [ABSTRACT FROM AUTHOR]

Copper-catalyzed sequential 1,3-dipolar cycloadditions of azomethine imines and alkynes and electrophilic thiolations are described. The C−S, C−N, and C−C bonds were simultaneously formed in one pot, leading to N,N-bicyclic pyrazolidinones in good to excellent yields. The process is proposed to proceed via reaction of a cuprate pyrazolidinonate intermediate and benzenesulfonothioate. [ABSTRACT FROM AUTHOR]

China, as an important source country in the global value chain, especially in the East Asian production networks, has exerted significant influence on Sino–Japanese trade fluctuations. This paper explores the real factors that lead to the fluctuations in Sino–Japanese trade. Using the Hodrick–Prescott filter technique and OECD–WTO Statistics on Trade in Value Added from 1995 to 2011, the impact of the changing comparative advantage between the two countries is also examined. The empirical results indicate that determinants of the fluctuations in Sino–Japapese trade include changing comparative advantages, the volatility of the real exchange rate and quite a few external shocks. Some policy suggestions are put forward in regards to the stability of trade between the two countries. [ABSTRACT FROM AUTHOR]

Vibrio alginolyticus is an important pathogen that causes a variety of diseases in marine animals including the sea cucumber, Apostichopus japonicus. Herein, we describe a two-phage mixture which may have potential for use as an antibacterial agent to prevent V. alginolyticus infection in the sea cucumber. A Z1210 bacterial isolate was cultured from diseased sea cucumber suffering from skin ulcerations and viscera ejection. The isolate was identified as V. alginolyticus by morphology and sequence similarity analysis. Subsequently, two bacteriophages infecting isolate Z1210 were isolated from the drainpipe of an aquatic market. Morphologically, these two phages were classified as members of Podoviridae ( PVA1) and Myoviridae ( PVA2) and each phage showed high virulence in an in vitro experiment. Additionally, an experiment conducted in a marine environment showed that a mixture of the two phages increased the survival of sea cucumbers (10 ± 2 g) to 73, 50, and 47% when it was used with a multiplicity of infection of 10, 1, or 0.1, respectively. This result differed markedly from the control without phage (3% survival) while there was no significant difference between the 80 and 47% survival observed for two antibiotic treatments (5 mg/L doxycycline and 10 mg/L kanamycin, respectively). [ABSTRACT FROM AUTHOR]

Background & Aims In Western countries, transjugular intrahepatic portosytemic shunt ( TIPS) is widely applied for the treatment of Budd-Chiari syndrome ( BCS). However, the outcome of Chinese BCS patients treated with TIPS is extremely limited. Furthermore, the timing of conversion from percutaneous recanalization to TIPS remains uncertain. Methods All consecutive BCS patients treated with TIPS between December 2004 and June 2012 were included. Patients were classified as the early and converted TIPS groups. Indications, TIPS-related complications, post- TIPS hepatic encephalopathy, shunt dysfunction and death were reported. Results Of 51 patients included, 39 underwent percutaneous recanalization for 1024 days (0-4574) before TIPS. Early TIPS group ( n = 19) has a shorter history of BCS and a lower proportion of prior percutaneous recanalization than converted TIPS group ( n = 32). Main indications were diffuse obstruction of three HVs ( n = 12), liver failure ( n = 2), liver function deterioration ( n = 8), refractory ascites ( n = 10) and variceal bleeding ( n = 19). Procedure-related intraperitoneal bleeding was reversible in three patients. The cumulative 1-year rate of being free of first episode of post- TIPS hepatic encephalopathy and shunt dysfunction was 78.38 and 61.69% respectively. The cumulative 1-, 2-, and 3-year survival rates were 83.82, 81.20 and 76.93% respectively. BCS- TIPS score, but not Child-Pugh, MELD, Clichy or Rotterdam score, could predict the survival. Age, total bilirubin and inferior vena cava thrombosis were also significantly associated with overall survival. Survival was similar between early and converted TIPS groups. Conclusions TIPS can achieve an excellent survival in Chinese patients in whom percutaneous recanalization is ineffective or inappropriate. BCS- TIPS score could effectively predict these patients' survival. [ABSTRACT FROM AUTHOR]

In this paper, the anti-depressant effects of Acanthopanax senticosus extract (ASE) were studied using animal models of depression including the forced swimming and tail suspension tests. The anti-depressive mechanism of ASE was explored by monitoring the levels of monoamine neurotransmitters including 5-hydroxytrylamine (5-HT), norepinephrine (NE), and dopamine (DA), as well as cAMP response element-binding (CREB) protein expression in the whole brain of mice following the tail suspension test. Our results showed that intragastric administration of ASE at a dose of 2000 mg/kg for seven days significantly reduced the duration of immobility in both the forced swimming test and the tail suspension test. These results indicate that ASE possesses antidepressant-like properties. Pre-treatment with 2000 mg/kg of ASE for seven days significantly elevated the levels of 5-HT, NE, and DA in the whole brain of mice. Moreover, ASE at doses of 1000 and 2000 mg/kg significantly up-regulated the level of CREB protein. Taken together, these findings suggest that the anti-depressive mechanism of ASE may be mediated via the central monoaminergic neurotransmitter system and CREB protein expression. Therefore, administration of ASE may be beneficial for patients with depressive disorders. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Bio-inspired approaches for mimicking the mineralization process of hydroxyapatite (HAp) with highly regulated structures have been intensively developed using biomacromolecular templates. In the present study, zein, a hydrophobic natural protein, was explored to induce the biomineralization of HAp nanocrystallites on the unique nanofibrous structures generated by electrospinning. Zein electrospun fibers with diameters range from several hundred nanometers down to 100 nm were obtained using formic acid as solvent. Randomly oriented apatite crystals were observed on zein nanofibrous membranes after several incubating cycles. The nature of the deposited mineral phase was confirmed as HAp crystallites by energy-dispersive spectroscopy, Fourier transform infrared spectroscopy, and wide-angle X-ray diffraction. A preliminary study of in vitro cytotoxicity and osteoblast adhesion revealed that mineralized zein nanofibrous membranes did not induce cytotoxic effects and had a positive effect on osteoblast growth. Zein/HAp membranes possessed the unique nanofibrous structural features and coating of HAp nanocrystallites may have a wide variety of potential applications for bone repair and regeneration. POLYM. COMPOS., 34:1163-1171, 2013. © 2013 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Background and Aim Routine screening for paroxysmal nocturnal hemoglobinuria ( PNH) in patients with Budd-Chiari syndrome ( BCS) or portal vein thrombosis ( PVT) has been recommended in Western countries. However, little is known about whether the routine screening test should be necessary in Chinese patients with BCS or PVT. We conducted a prospective observational study to examine the prevalence of PNH in these patients. Methods Patients with primary BCS or non-malignant PVT who were consecutively admitted to our department or regularly followed up between September 2009 and December 2011 were eligible for the study and detected the expression of CD55 and CD59 on erythrocytes and granulocytes. The CD55 or CD59 deficiency was considered as the proportion of erythrocytes or granulocytes with normal expression of CD55 or CD59 was less than 90%. PNH was diagnosed by both CD55 and CD59 deficient clone at flow cytometry of peripheral blood cells. Results CD55 and/or CD59 deficiencies were found in 1.6% (2/127) of patients with primary BCS, 1.0% (1/100) of non-malignant and non-cirrhotic patients with PVT, and 4.7% (4/85) of cirrhotic patients with PVT. Only one patient had both CD55 and CD59 deficiencies on granulocytes. But he had been diagnosed with PNH before BCS. Conclusions Paroxysmal nocturnal hemoglobinuria was very rare in Chinese patients with BCS or PVT, suggesting that routine screening for PNH should not be indiscriminately performed in such patients. [ABSTRACT FROM AUTHOR]

Catellani reactions of aryl iodides allow the double functionalization at the ortho and ipso positions in one pot. Catellani reactions involving a nitrene intermediate are not yet known. In this paper, a few palladium amino complexes were prepared from PdCl2, anthranil and iodoarenes, and their structures were determined by X‐ray single‐crystal diffraction. These complexes are supported by a pincer C,N,O tridentate ligand forming fused six‐membered palladacycles. The high stability of the palladium complexes inhibits their reductive elimination. Novel palladium amido complexes were synthesized from palladium chloride, phosphines, anthranil, and norbornene via one‐pot reaction, and their structures were characterized. [ABSTRACT FROM AUTHOR]

Ortho-substituted aryl iodides undergo a site-selective C-H bond acylation/C-I cyanation reaction sequence with benzoyl chlorides and CuCN to give 2,6-disubstituted benzonitriles. [ABSTRACT FROM AUTHOR]

Using carbene transfer reactions, four new rhodium complexes of N-heterocyclic carbenes, e.g. RHC, are prepared. [ABSTRACT FROM AUTHOR]

An abstract of the article "One-Pot Synthesis of 2,3-Disubstituted Dihydrobenzofurans and Benzofurans via Rhodium-Catalyzed Intramolecular C-H Insertion Reaction" by Xueji Ma, Feifei Wu and colleagues is presented.

The article presents steps of the chemical equations involved in the synthesis of benzenesulfonamide.