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OBJECTIVE: Observe the expression and distribution of HMGB1 in Sombati's cell model and kainic acid-induced epileptic rats' model. MATERIALS AND METHODS: Dissociated hippocampal neurons from neonatal SD rats and cultured those for 9 days, then changed medium to Mg2+-free medium for 3 hours to induce Sombati's cell model. The expression level of HMGB1 in the neurons was detected at 24h and 72h by Western Blotting. Appropriate kainic acid was injected into the lateral ventricles to induced epileptic rats' model in vivo trial, the expression level and distribution of HMGB1 at 24h and 72h were established by immunohistochemistry. RESULTS: The expression level of HMGB1 showed significantly different between model group and control group both in vitro and in vivo trials. At 24h, the expression level of HMGB1 in the model group was lower than the control group (p < 0.05), and became higher than the control group at 72h (p < 0.05). From the in vivotrial, a nucleus-to-cytoplasm translocation was also discovered. CONCLUSIONS: This investigation indicates that HMGB1 plays a crucial role in the pathophysiology of epilepsy, by altering its quantity and distribution. [ABSTRACT FROM AUTHOR]

Drought has been a concern of global and regional water, carbon and energy cycles. From 1999 to 2011, North China experienced a multiyear precipitation reduction, which decreased significantly water availability as indicated by decreased soil moisture and Palmer Drought Severity Index. In this study, three light use efficiency models (CASA, MODIS-GPP and EC-LUE) and one dynamic vegetation model (IBIS) were used to characterize the impacts of long-term drought on terrestrial carbon fluxes over the North China. All of four models showed the reduction in averaged GPP of 0.026-0.047 Pg C yr-1 from 1999 to 2011 compared to 1982-2011. Based on IBIS model, simulated ecosystem respiration fell from 1999 to 2011 by 0.016 Pg C yr-1. Multiple precipitation reduction changed the regional carbon uptake of 0.0014 Pg C yr-1 from 1982 to 1998 to a net source of 0.018 Pg C yr-1. Moreover, a pronounced decrease of maize yield was found ranging from 1999 to 2011 versus the average of 1978-2011 at almost all provinces over the study region. The largest reduction of maize yield occurred in the Beijing (2499 kg ha-1 yr-1), Jilin (2180 kg ha-1 yr-1), Tianjing (1923 kg ha-1 yr-1) and Heilongjiang (1791 kg ha-1 yr-1), and maize yield anomaly was significantly correlated with the precipitation through May and September over the entire study area. Our results revealed that recent climate change, and especially drought-induced water stress, is the dominant cause of the reduction in the terrestrial carbon sink. [ABSTRACT FROM AUTHOR]

The behavior of groundwater response to leakage of surface water in the middle reaches area of Heihe River Basin is significantly influenced by a thick vadose zone. The groundwater regime is a result of two recharge events due to leakage of Heihe River and irrigation water with different delay time. A nonlinear leakage model is developed to calculate the monthly leakage of Heihe River in considering changes of streamflow, river stage and agricultural water utilization. Numerical modeling of variable saturated flow is carried out to investigate the general behaviors of leakage-recharge conversion through a thick vadose zone. It is found that the recharge pattern can be approximated by simple reservoir models of leakages under a river and under an irrigation district with different delay-time and recession coefficient. A triple-reservoir model of relationship between surface water, vadose zone and groundwater is developed. It reproduces the groundwater regime during 1989-2006 with variable streamflow of Heihe River and agricultural water utilization. The model is applied to interpret changes of groundwater level during 2007-2008 that observed in the Watershed Airborne Telemetry Experimental Research (WATER). [ABSTRACT FROM AUTHOR]

The behavior of groundwater response to leakage of surface water in the middle reaches area of Heihe River Basin is significantly influenced by a thick vadose zone. The variation of groundwater level is a result of two recharge events corresponding to 5 leakage of Heihe River and irrigation water with different delay time. A nonlinear leakage model is developed to calculate the monthly leakage of Heihe River in considering changes of streamflow, river stage and agricultural water utilization. Numerical modeling of variable saturated flow is carried out to investigate the general behaviors of leakage-recharge conversion through a thick vadose zone. It is found that the variable recharge can be approximated by simple reservoir models for both leakage under a river and leakage under an irrigation district but with different delay-time and recession coefficient. A triple-reservoir model of relationship between surface water, vadose zone and groundwater is developed. It reproduces the in situ water table movement during 1989-2006 with variable streamflow of Heihe River and agricultural water utilization. The model is applied to interpret groundwater dynamics during 2007-2008 that observed in the Watershed Airborne Telemetry Experimental Research (WATER). [ABSTRACT FROM AUTHOR]

A field campaign was carried out in the alpine meadow of Heihe River Basin, north-west China on 11-15 July 2002. Several bio-geophysical parameters such as leaf area index (LAI) were measured according to VALERI sampling procedures within 38 elementary sampling units (ESUs) in the 3 km × 3 km 'VALERI' site. A quarter scene of Landsat 7 ETM + with acquisition times close to the field campaign time was atmospherically and geographically corrected. Three kinds of spectral vegetation index maps including NDVI, SR and MSAVI in the sampling area were derived from the corrected ElM + image. The two sets of LA! data measured with LAI-2000 and TRAC instrument at the same site were inter-compared. This is particularly meaningful for assessing the accuracy of LAI measurements. The relationships between the measured LAI and the three kinds of vegetation indices were also investigated. These comparisons found good relationships between the measured LAI and the different vegetation indices in most cases. Among them, NDVI seems the most promising estimator for extraction of LAI for the alpine meadow. In addition, the LAI-2000 seems to perform better for LAI measurement in the alpine meadow than the TRAC instrument. [ABSTRACT FROM AUTHOR]

Solid- and solution-phase synthesis of peptidomimetic inhibitors of urokinase-type plasminogen activator based on the sequence dSerAlaArg-al are described. The biological activities of these unique inhibitors are reported herein. Carbonate prodrugs were prepared and tested as potential drug delivery systems.

An assay for the quantification of plasma and urine levels of CVS 1123, an orally bioavailable thrombin inhibitor, and its desmethyl form. CVS 738, was developed to support clinical and toxicology studies. This assay uses solid-phase extraction, reversed-phase HPLC separation, and post-column fluorescent derivatization with ninhydrin. An internal standard is added to correct for recovery. In aqueous solution, the arginine aldehyde structures of CVS 1123 and CVS 738 exist in multiple forms which can be separated under standard reversed-phase HPLC conditions. HPLC conditions were optimized to give rapid interconversion of the forms on the separation time scale, and consequently a single chromatographic peak. Extraction conditions were modified for quantitative extraction of drug compounds from large volumes of human plasma. The assay was shown to be accurate and precise, with a quantification limit of 17 ng CVS 1123/ml human plasma.