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Green manuring is a common practice in replenishment of soil organic matter and nutrients in rice paddy field. Owing to the complex interplay of multiple factors, the oxidation–reduction (redox) properties of dissolved organic matter (DOM) from green manure crops are presently not fully understood. In this study, a variety of surrogate parameters were used to evaluate the redox capacity and redox state of DOM derived from Chinese milk vetch (CMV,Astragalus sinicusL.) via microbial decomposition under continuously flooded (CF) and non-flooded (NF) conditions. Additionally, the correlation between the surrogate parameters of CMV–DOM and the kinetic parameters of relevant redox reactions was evaluated in a soil–water system containing CMV–DOM. Results showed that the redox properties of CMV–DOM were substantially different between the fresh and decomposed CMV–DOM treatments. Determination of the surrogate parameters via ultraviolet–visible/Fourier transform infrared absorption spectroscopy and gel permeation chromatography generally provided high-quality data for predicting the redox capacity of CMV–DOM, while the surrogate parameters determined by elemental analysis were suitable for predicting the redox state of CMV–DOM. Depending on the redox capacity and redox state of various moieties/components, NF-decomposed CMV–DOM could easily accelerate soil reduction by shuttling electrons to iron oxides, because it contained more reversible redox-active functional groups (e.g. quinone and hydroquinone pairs) than CF-decomposed CMV–DOM. This work demonstrates that a single index cannot interpret complex changes in multiple factors that jointly determine the redox reactivity of CMV–DOM. Thus, a multi-parametric study is needed for providing comprehensive information on the redox properties of green manure DOM. [ABSTRACT FROM PUBLISHER]

There is growing interest in investigations into soil carbon (C) sequestration, plant nutrients and biological activities in organic farming since it is regarded as a farming system that could contribute to climate mitigation and sustainable agriculture. However, most comparative studies have focused on annual crops or farming systems with crop rotations, and only a few on perennial crops without rotations, e.g. tea (Camellia sinensis(L.) O. Kuntze). In this study, we selected five pairs of tea fields under organic and conventional farming systems in eastern China to study the effect of organic farming on soil C sequestration, plant nutrients and biological activities in tea fields. Soil organic C, total nitrogen (N), phosphorus (P), potassium (K) and magnesium (Mg), available nutrients, microbial biomass, N mineralization and nitrification were compared. Soil pH, organic C and total N contents were higher in organic tea fields. Soil microbial biomass C, N and P, and their ratios in organic C, total N and P, respectively, net N mineralization and nitrification rates were significantly higher in organic fields in most of the comparative pairs of fields. Concentrations of soil organic C and microbial biomass C were higher in the soils with longer periods under organic management. However, inorganic N, available P and K concentrations were generally lower in the organic fields. No significant differences were found in available calcium (Ca), Mg, sodium (Na), iron (Fe), manganese (Mn), copper (Cu) and zinc (Zn) concentrations between the two farming systems. These findings suggest that organic farming could promote soil C sequestration and microbial biomass size and activities in tea fields, but more N-rich organic fertilizers, and natural P and K fertilizers, will be required for sustainable organic tea production in the long term. [ABSTRACT FROM PUBLISHER]

A pot experiment was conducted to study the effects of adding 100 and 500 mg·kg-1 of exogenous iron (Fe) on the lead (Pb) accumulation in Typha latifolia growing on a soil with 0, 100, 500 and 1000 mg·kg-1 of Pb, respectively. In treatment 500 mg Fe·kg-1, the Pb concentration in T. latifolia shoots and roots was higher, compared with that in treatment 100 mg Fe·kg-1. When the soil Pb concentration was 1000 mg·kg-1, the Pb concentration in T. latifolia shoots and roots in treatment 500 mg Fe·kg-1 increased by 33. 7% and 50. 5%, respectively, compared with that in treatment 100 mg Fe·kg-1. The exchangeable Pb concentration in rhizosphere soil was 77. 0% -114. 6% higher in treatment 500 mg Fe·kg-1 than in treatment 100 mg Fe·kg-1. When the soil Pb concentration was 0, 100 and 1000 mg·kg-1, the root dry mass in treatment 500 mg Fe · kg-1 had a significant decrease, compared with that in treatment 100 mg Fe·kg-1. It was suggested that adding appropriate amount of Fe to Pb-contaminated wetland soil could increase the availability of soil Pb and improve the Pb accumulation in plants. [ABSTRACT FROM AUTHOR]

Aim: We conducted this study to evaluate the role of multidetector computed tomography (MDCT) in diagnosing and differential diagnosis hepatic veno-occlusive disease (HVOD), and as well as assessing the clinical therapeutic effects. Methods: From 2007 to 2010, 10 inpatients with weight increasing, liver pains, ascites, jaundice and history of taking gynura rhizome before hospitalization were scanned with a 64-MDCT. The data were reconstructed every 0.625 mm and reviewed using multiplanar reconstruction (MPR) and liver CT angiography (CTA) on a GE AW4.2 workstation. Patients were re-scanned with MDCT after medication so that the clinical therapeutic effect could be evaluated before the patients discharging from hospital. Results: In 10 HVOD patients, the diagnoses of MDCT were coincident with clinical results. All patients had ascites and pleural fluid, hepatomegaly except the caudate lobe in MDCT. Failure to view hepatic veins in hepatic 3 phase scans, but portal veins and inferior vena cava were unobstructed. In portal-phase, hepatic enhancements were non-uniform. Three patients were incorrectly diagnosed before hospital admission. All patients improved significantly after hepato-protection and supporting therapy. No ascites, hydrothorax, hepatomegaly and obstruction of hepatic veins were observed by MDCT before patients were discharged from hospital. Conclusion: Multidetector computed tomography combined with MPR and liver CTA images are helpful in the diagnosis and differential diagnosis of HVOD and in the evaluation of clinical therapeutic effects. [ABSTRACT FROM AUTHOR]

Background and Aims: Collagen type IV and hyaluronic acid (HA) are the major components of basement membrane and extracellular matrix, respectively. Cathepsin D is an aspartyl lysosomal protease involved in the degradation of the basement membrane and extracellular matrix. The aim of this study is to investigate the clinical significance of collagen type IV and hyaluronic acid in gastric juice and serum in diagnosis of gastric cancer and the degrading effect of cathepsin D on collagen type IV and HA.Methods: Fifty gastric cancer patients were enrolled in our study compared with 41 patients with precancerous lesion and 30 control subjects. Collagen type IV and HA in gastric juice and serum were analyzed by radioimmunoassay. Expression of cathepsin D and collagen type IV in tissue were analyzed by immunohistochemical staining with monoclonal antibodies.Results: The contents of collagen type IV and HA in gastric juice and HA in serum were significantly higher in patients with gastric cancer than those in patients with precancerous lesion and control group (p < 0.05, p < 0.0001). Gastric cancer patients with lymph node metastasis had a higher level of collagen type IV and HA in gastric juice than those in patients without metastasis (p = 0.049, p = 0.043). The expression of cathepsin D had significantly increased in patients with gastric cancer compared to the control group (p < 0.0001). The continuous expression of collagen type IV in basement membrane in gastric cancer group was lower than that in the precancerous lesion group and control group (p < 0.0001).Conclusions: The analysis of collagen type IV and HA in gastric juice and serum may provide a simple aid in diagnosing gastric cancer and evaluating whether metastasis is occurring or not. [ABSTRACT FROM AUTHOR]

The effect of trastuzumab on patients with HER-2/neu (HER2)-positive gastric cancer has been confirmed in a phase III clinical trial (ToGA study). However, the optimized sequence and synergic mechanism of trastuzumab and chemotherapy are not clear. Our study investigated the effects and mechanisms of trastuzumab in combination with 5-Fluorouracil (5-Fu) or cisplatin (DDP) on gastric cancer cell lines. Flow cytometry was used to determine HER2 expression and cell cycle. MTT assay was performed to evaluate cytotoxicity. Western blotting and RT-PCR were used to analyze signaling transduction and mRNA expression. Sequential 5-Fu followed by trastuzumab and trastuzumab plus DDP followed by trastuzumab produced the best inhibitory effects. Inhibition of HER2-PI3K-AKT signal transduction, downregulation of nucleotide excision repair cross-complementation 1 (ERCC1), and interference with cell cycle distribution may elucidate the synergism between trastuzumab and chemotherapy. These results provide some evidence for designing a rational regime when trastuzumab is being considered to be used in patients with gastric cancer. [ABSTRACT FROM AUTHOR]

Obesity is a medical condition in which excess body fat has accumulated to an extent and may have an adverse effect on health, leading to reduced life expectancy, impaired energy homeostasis and increased health problems. The p160 steroid receptor coactivator (SRC) gene family members have been suggested to be involved in energy homeostasis, but the impact of SRC-3 ablation on white and brown adipose tissue needs to be elucidated. In the current study, we collected in vivo data and carried out morphological studies on the effect of SRC-3 deficiency on white adipose tissue (WAT) and brown adipose tissue (BAT). Primary cells were cultured to investigate the differentiation ability of both adipocytes. Western blot was applied to detect the expression of master genes governing adipogenesis and thermogenesis. We observed that SRC-3−/− mice were lean, with reduced WAT and decreased serum leptin levels, mainly due to the smaller white adipocyte size caused by impaired adipogenesis, presented by decreased peroxisome proliferator activated receptor γ (PPARγ) expression. In the BAT, the lipid droplets decreased significantly in SRC-3−/− mice as demonstrated by histological analysis and electron microscopic observation, which could be explained by enhanced thermogenesis. The expression of thermogenic marker gene PPARγ coactivator 1α and uncoupling protein-1 increased in BAT of SRC-3−/− mice, which proved our observations. Collectively, these results demonstrate that SRC-3 plays a key role in adipogenesis and energy expenditure. [ABSTRACT FROM AUTHOR]

Abstract: Regioselective Michael addition of purine derivatives to α,β-unsaturated carbonyl compounds could be catalyzed by d-aminoacylase amano (DA) in DMSO. The influence of reaction conditions on the Michael addition, including solvent, temperature, and enzyme concentration was systematically investigated. Then we extended this methodology to six structurally diverse purine derivatives and a variety of α,β-unsaturated carbonyl compounds. 21 Michael adducts were selectively synthesized in moderate to high yields. It is the first report on enzyme-catalyzed Michael addition for the preparation of purine derivatives. [Copyright &y& Elsevier]

Based on the long-term field experiment at Hailun Agro-ecosystem Experimental Station of Chinese Academy of Sciences, this paper studied the cadmium (Cd) accumulation, its development tendency, and Cd availability in black soil under effects of long-term application of chemical N and P fertilizers and pig manure. The results showed that under no fertilization, soil Cd concentration had a slight increase. Long-term chemical N and P fertilization increased soil Cd concentration significantly, but soil Cd accumulation had less difference under different N and P fertilization rates. Applying pig manure increased the Cd accumulation in soil significantly, and the accumulation had a tendency of speed-up. Cd-containing feedstuff additives could be the important source of Cd in pig manure. No significant effects of chemical N and P fertilization were observed on the Cd availability in soil, but long-term application of pig manure increased the Cd availability significantly. [ABSTRACT FROM AUTHOR]

Abstract: This paper is concerned with the problem of H ∞ control for two-dimensional (2-D) discrete state delay systems described by the second Fornasini and Marchesini (FM) state-space model. A sufficient condition to have an H ∞ noise attenuation for this 2-D system is given in terms of a certain linear matrix inequality (LMI). The optimal H ∞ controller is obtained by solving a convex optimization problem. Finally, a simulation example is given to illustrate the effectiveness of the proposed result. [Copyright &y& Elsevier]

A simple and efficient method for selective construction of morphlin-2-one and morphlin-3-one heterocyclic derivatives has been developed from N-substituted aminoethanols and divinyl fumarate. The selectivity of this catalyst-free reaction was easily controlled by different solvents. [ABSTRACT FROM AUTHOR]

Abstract: A novel strategy to perform Michael additions between 1,3-dicarbonyl compounds and α,β-unsaturated compounds was developed by the catalysis of hydrolase. We found that 11 hydrolase could catalyze the enzymatic Michael addition reaction to form the carbon–carbon bond. In 2-methyl-2-butanol d-aminoacylase showed high Michael addition activity. The influence of substrate and Michael acceptor structure on Michael addition was evaluated systematically. Some control experiments demonstrated that the active site of d-aminoacylase was responsible for the enzymatic Michael addition reaction. This novel Michael addition activity of hydrolase is of practical significance in expanding the application of enzymes and in the evolution of new biocatalysts. [Copyright &y& Elsevier]

Abstract: A facile and efficient strategy to prepare drug derivatives with saccharides was developed, and 12 drug–saccharide conjugates were obtained by selective enzymatic synthesis methods. When the transesterification of chlorphenesin vinyl esters with glucose was chosen as a model reaction, the influence of reaction conditions was optimized. Then, we successfully prepared a series of chlorphenesin–saccharide derivatives of three monosaccharides (glucose, mannose and galactose) and three disaccharides (maltose, lactose and sucrose). In order to study the relationship between the solubility of drug–saccharide conjugates and the structure of parent drugs, five hydrophobic drugs (chlorphenesin, mephenesin, guaifenesin, propranolol and clorprenaline) were chosen as substrates to synthesize drug–saccharide conjugates. The results indicated that the aqueous solublity of drug–saccharide derivatives was greatly improved, which was changed by different saccharides and the structure of parent drugs. [Copyright &y& Elsevier]