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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]

Background. Patients with severe ulcerative colitis (SUC) have a high risk of requiring colectomy or resorting to a second-line treatment. However, neither clinical outcomes nor factors predictive of poor response have been clearly established in the treatment of SUC. Objective. To assess prospectively the effects and predictors of corticosteroids (CS) use in clinical outcomes of SUC during 1 year of follow-up. Material and methods. Consecutive inpatients with SUC, who had been treated with intravenous CS, were enrolled. Patients were monitored by clinical, laboratory, and endoscopic examinations, and the data were recorded for 1 year. Univariate and multivariate analyses were performed at 1 week. Results. There were 22.6% (14/62) nonresponders at 7 days. Several predictors were associated with nonresponse to CS. These included Mayo Score at baseline ( p = 0.007), partial Mayo Score, number of bowel movements, blood presence in stool, abdominal pain, and levels of C-reactive protein (CRP), hemoglobin (Hgb), platelet count (PLT), and erythrocyte sedimentation rate (ESR) on day 3 ( p < 0.05). Multiple logistic regression analysis identified the Partial Mayo Score at day 3 as an independent predictor of outcome ( p = 0.012). A total of 12 patients underwent colectomy within 1 year. The short-term response rates to intravenous cyclosporin (CsA) and infliximab (IFX) in SUC were 71.4% (5/7) and 77.8% (7/9), respectively. Conclusions. Many patients with SUC eventually became refractory to or dependent on CS. The Mayo score and laboratory characteristics were factors useful in predicting short-term outcome of CS treatment. Secondary medical therapy can help avoid emergency surgery. [ABSTRACT FROM AUTHOR]

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]

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]