[Availability Changes in Different Exogenous Selenium Fertilizers in Soil and Their Effects on Selenium Accumulation in Wheat].

In order to understand the differences in the uptake and accumulation of several common exogenous selenium fertilizers by crops, a wheat pot experiment was conducted to study the availability changes in different selenium fertilizers (potassium selenate, potassium selenite, EDTA-chelated selenium, selenium powder, fly ash, and selenium-enriched straw) in soil and their effects on wheat growth and selenium uptake and distribution. The results showed that the change in availability of different exogenous selenium types in soil was different. During the whole growth period of wheat, the soil available selenium proportion of selenate, selenite, and EDTA-chelated selenium treatment was significantly higher than that of the control (CK), respectively, but there was no significant difference between the other treatments and the CK treatment. In the early stage of wheat growth, the soil available selenium proportion of selenate, selenite, and selenium powder treatment decreased gradually and tended to be stable in the later growth stage of wheat; however, the soil available selenium proportion of other exogenous selenium treatments showed a dynamic change of decreasing in the early period and increasing in the late period. The available selenium content in soil significantly affected the selenium uptake by wheat, and there was a significant positive correlation between them. Selenate application significantly increased the grain and leaf biomass of wheat, but other selenium fertilizers had no significant effect on wheat growth. The accumulation capacity of different exogenous selenium fertilizers for wheat followed the order of selenate>selenite, EDTA-chelated selenium>selenium powder, fly ash, and selenium-enriched straw. There was no significant difference between the selenium powder, fly ash, and selenium-enriched straw treatments and the CK treatment. Selenium was more easily transferred to and accumulated in the stems and leaves of wheat after the application of selenate, whereas selenium was more easily transferred to and accumulated in grains after the application of selenite and EDTA-chelated selenium.

Selenium enhances iron plaque formation by elevating the radial oxygen loss of roots to reduce cadmium accumulation in rice (Oryza sativa L.).

The inhibition of cadmium (Cd) absorption by selenium (Se) in rice may be associated with iron plaque (IP) formation, but the driving mechanisms are still unclear. This study investigated the effects of Se on the growth, oxidative toxicity, radial oxygen loss (ROL), IP formation, and Cd absorption of rice exposed to Cd. The results of this study showed that Cd stress elevated the levels of O2- and H2O2 and depressed superoxide dismutase (SOD) and catalase (CAT) activities. The maximum ROL and IP were reduced by 43.3 % and 74.5 %, respectively. However, Se alleviated Cd toxicity by stimulating SOD and CAT activities by scavenging O2- and H2O2 and enhancing the ROL profiles. Under culture conditions without Fe2+, Se had no impact on the total Cd levels in rice (TCd). However, with the addition of Fe2+, TCd was significantly reduced by 23.3 % due to the enhancement of IP formation by Se. These results indicated that Se can reduce Cd accumulation in rice in the presence of Fe2+ treatments. However, Se just alleviated Cd toxicity in the absence of Fe2+ treatments. The enhancement of ROL was a potential reason for the elevated IP formation induced by Se.

Characteristics of Time-Dependent Selenium Biofortification of Rice ( Oryza sativa L.).

The application of selenite to soil has increasingly been used to produce Se-enriched food. This study investigated the biofortification characteristics of Se in rice after application of selenite to soil at different growth stages. The results showed that the application of Se during booting stage resulted in the highest concentration of Se in brown rice due to the highest upward translocation of Se. More than 90% of Se in the brown rice was organic species, with selenomethionine predominated. The proportion of selenomethionine in the brown rice decreased with the delay in application time. The rice grown in the acidic soil had higher Se concentrations than in the neutral soil. With increasing soil Cd level, Se accumulation and the proportion of Se-methylselenocysteine in the brown rice were reduced. This study provides a theoretical basis for the production of Se-enriched rice in clean soil or slightly to moderately Cd-contaminated soil.

Impacts of Small-Scale Industrialized Swine Farming on Local Soil, Water and Crop Qualities in a Hilly Red Soil Region of Subtropical China.

Industrialized small-scale pig farming has been rapidly developed in developing regions such as China and Southeast Asia, but the environmental problems accompanying pig farming have not been fully recognized. This study investigated 168 small-scale pig farms and 29 example pig farms in Yujiang County of China to examine current and potential impacts of pig wastes on soil, water and crop qualities in the hilly red soil region, China. The results indicated that the small-scale pig farms produced considerable annual yields of wastes, with medians of 216, 333 and 773 ton yr-1 per pig farm for manure, urine and washing wastewater, respectively, which has had significant impact on surface water quality. Taking NH4⁺-N, total nitrogen (TN) or total phosphorus (TP) as a criterion to judge water quality, the proportions of Class III and below Class III waters in the local surface waters were 66.2%, 78.7% and 72.5%. The well water (shallow groundwater) quality near these pig farms met the water quality standards by a wide margin. The annual output of pollutants from pig farms was the most important factor correlated with the nutrients and heavy metals in soils, and the relationship can be described by a linear equation. The impact on croplands was marked by the excessive accumulation of available phosphorus and heavy metals such as Cu and Zn. For crop safety, the over-limit ratio of Zn in vegetable samples reached 60%, other heavy metals in vegetable and rice samples tested met the food safety standard at present.

Underlying mechanisms and effects of hydrated lime and selenium application on cadmium uptake by rice (Oryza sativa L.) seedlings.

A pot experiment was conducted to investigate the effects of selenium (Se) and hydrated lime (Lime), applied alone or simultaneously (Se+Lime), on growth and cadmium (Cd) uptake and translocation in rice seedlings grown in an acid soil with three levels of Cd (slight, mild, and moderate contamination). In the soil with 0.41 mg kg-1 Cd (slight Cd contamination), Se addition alone significantly decreased Cd accumulation in the root and shoot by 35.3 and 40.1%, respectively, but this tendency weakened when Cd level in the soil increased. However, Se+Lime treatment effectively reduced Cd accumulation in rice seedlings in the soil with higher Cd levels. The results also showed that Se application alone strongly increased Cd concentration in the iron plaque under slight Cd contamination, which was suggested as the main reason underlying the inhibition of Cd accumulation in rice seedlings. Se+Lime treatment also increased the ability of the iron plaques to restrict Cd uptake by rice seedlings across all Cd levels and dramatically decreased the available Cd concentration in the soil. These results suggest that Se application alone would be useful in the soil with low levels of Cd, and the effect would be enhanced when Se application is combined with hydrated lime at higher Cd levels.

Differential responses of soil nematode community to pig manure application levels in Ferric Acrisols.

Excessive pig manure application probably degrades arable soil quality in some intensive pig farming areas. The responses of the nematode community to dosages of pig manure were investigated in Ferric Acrisols under 3-season peanut monoculture. Varying dosages of manure (1.75, 3.5, 7, 14 and 28 t·ha-1·yr-1) in combination with chemical fertilizer were applied to field plots, and chemical fertilizer alone was also applied as a control. With increasing manure application, the abundance of bacterivores and omnivores-predators increased, the abundance of plant parasites decreased, and fungivores abundance exhibited hump-shaped variation. Simpson diversity index and plant parasite index/maturity index of the nematode communities increased to a maximum level at a manure application rate of 3.5 t·ha-1·yr-1 and then sharply decreased. The changes in the soil nematode community were further determined to be correlated with chemical properties; available phosphorus had the strongest quadratic correlation with the two indices, implying that available phosphorus had a better indicative effect than other soil properties to nematode community. Available phosphorus in soil was deduced from 49 to 64 mg·kg-1 with the best nematode communities. Our results emphasized the importance of regular applications of manure in agriculture field to balance nematode diversity and build healthy agro-ecosystems.

Derivation of soil thresholds for lead applying species sensitivity distribution: A case study for root vegetables.

The combination of food quality standard and soil-plant transfer models can be used to derive critical limits of heavy metals for agricultural soils. In this paper, a robust methodology is presented, taking the variations of plant species and cultivars and soil properties into account to derive soil thresholds for lead (Pb) applying species sensitivity distribution (SSD). Three species of root vegetables (four cultivars each for radish, carrot, and potato) were selected to investigate their sensitivity differences for accumulating Pb through greenhouse experiment. Empirical soil-plant transfer model was developed from carrot New Kuroda grown in twenty-one soils covering a wide variation in physicochemical properties and was used to normalize the bioaccumulation data of non-model cultivars. The relationship was then validated to be reliable and would not cause over-protection using data from field experimental sites and published independent studies. The added hazardous concentration for protecting 95% of the cultivars not exceeding the food quality standard (HC5add) were then calculated from the Burr Type III function fitted SSD curves. The derived soil Pb thresholds based on the added risk approach (total soil concentration subtracting the natural background part) were presented as continuous or scenario criteria depending on the combination of soil pH and CEC.

Protective effects of tanshinone â ¡A on endothelial progenitor cells injured by tumor necrosis factor-α.

Tanshinone ⅡA (Tan ⅡA) is a Traditional Chinese Medicine commonly used in Asian and Western countries for the prevention and treatment of cardiovascular disorders, such as atherosclerosis. Endothelial dysfunction and associated inflammatory processes have a critical role in the development of atherosclerosis. Endothelial progenitor cells (EPCs) have been demonstrated to be involved in certain aspects of the endothelial repair process. The present study aimed to investigate the putative protective effects of Tan ⅡA on EPCs injured by tumor necrosis factor­α (TNF­α). The potential effects of Tan ⅡA on TNF-α-stimulated EPC proliferation, migration, adhesion, in vitro tube formation ability and paracrine activity were investigated in the current study. The results indicated that TNF­α impaired EPC proliferation, migration, adhesion capacity and vasculogenesis ability in vitro as well as promoted EPC secretion of inflammatory cytokines, including monocyte chemoattractant protein­1 (MCP­1), interleukin­6 (IL­6) and soluble CD40 ligand (sCD40L). However, Tan ⅡA was able to reverse these effects. In conclusion, these findings demonstrated that Tan ⅡA may have the potential to protect EPCs against damage induced by TNF­α. Therefore, these results may provide evidence for the pharmacological basis of Tan ⅡA and its potential use in the prevention and treatment of early atherosclerosis associated with EPC and endothelial damage.

Effects of soil type and genotype on cadmium accumulation by rootstalk crops: implications for phytomanagement.

The variations of Cd accumulation in three rootstalk crop species (radish, carrot and potato) were investigated by using twelve cultivars grown in acidic Ferralsols and neutral Cambisols under two Cd treatments (0.3 and 0.6 mg kg(-1)) in a pot experiment The result showed that the total Cd uptake was significantly affected by genotype, soil type and interaction between them, suggesting the importance of selecting proper cultivars for phytoextraction in a given soil type. Among the cultivars tested, potato cultivar Luyin No.1 in Ferralsols and radish cultivar Zhedachang in Cambisols exhibited the highest Cd phytoextraction efficiency in aerial parts (4.45% and 0.59%, respectively) under 0.6 mg kg-1 Cd treatment. Furthermore, the Cd concentrations in their edible parts were below the National Food Hygiene Standard of China (0.1 mg kg(-1), fresh weight). Therefore, phytomanagement of slightly Cd-contaminated soils using rootstalk crops for safe food production combined with long-term phytoextraction was feasible, and potato cultivar Luyin No.1 for Ferralsols and radish cultivar Zhedachang for Cambisols were promising candidates for this approach.

Resveratrol attenuates adenosine diphosphate-induced platelet activation by reducing protein kinase C activity.

Inappropriate platelet activation is the key point of thrombogenesis. The aim of the present study was to investigate the effects of resveratrol (RESV), a compound extracted from the Chinese medicinal herb Polygonum cuspidatum sieb et Zucc, on the platelet activation induced by adenosine diphosphate (ADP) and its possible mechanism. The percentage of platelet aggregation and surface P-selectin-positive platelets, and the activity of protein kinase C (PKC) of platelet were observed with platelet aggregometer, flow cytometry and phosphorimaging system, respectively. RESV at 25, 50 and 100 microM showed anti-platelet aggregation and inhibition of surface P-selectin-positive platelets in a concentration-dependent manner. RESV (50 microM) inhibited the activity of PKC in the membrane fraction of platelets and decreased the percentage of membrane associated PKC activity in total PKC activity. Moreover, DL-erythro-1,3-Dihydroxy-2-aminooctadecane, an elective protein kinase C inhibitor (PKCI), and RESV had additive effects of inhibiting the percentage of platelet aggregation and surface P-selectin-positive platelets. It is suggested that RESV may inhibit platelet aggregation, the percentage of surface P-selectin-positive platelets and subsequent thrombus formation. The mechanisms may be partly relative to the decrease of the activity of PKC of platelets.

[Inhibitory effect of resveratrol on cardiac fibroblast proliferation induced by angiotensin II].

OBJECTIVE: To observe the effect and mechanism of resveratrol on cardiac fibroblast (cFs) proliferation induced by angiotensin II (Ang II). METHODS: The in vitro cFs proliferation model was established by stimulating cultured cFs of new born rats with Ang II by differential attachment method. Cell proliferation was measured by MTT assay, and the effect of resveratrol, L-NAME and ODQ on cell proliferation were observed respectively. Besides, the hypertrophic response of cFs was estimated by measuring expressions of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) mRNA, with the levels of ANP and BNP in culture medium determined by radioimmunoassay and ELISA respectively; and their mRNA expressions determined by reverse transcription polymerase chain reaction (RT-PCR). Level of nitric oxide (NO) in the culture medium was measured by Griess reagent; nitric oxide synthase (NOS) level by chemical colorimetric method; and cGMP by radioimmunoassay. RESULTS: Resveratrol at the dose of 25-100 micromol/L inhibited cFs proliferation in a time and dose dependent manner, which could be partially blocked by pretreatment with L-NAME or ODQ. NO and cGMP levels increased, ANP, BNP levels and their mRNA expression lowered after resveratrol treatment. CONCLUSION: Resveratrol in a definite concentration range could inhibit cFs proliferation and hypertrophic response induced by Ang II, up-regulating the signal pathway of NO and cGMP might be one of the acting paths of the inhibitory effects.

[Inhibitory effects of emodin on proliferation of rat vascular smooth muscle cell induced by angiotensin II].

OBJECTIVE: To investigate the effects of emodin on the proliferation of cultured rat vascular smooth muscle cell (VSMC) induced by angiotensin II. METHOD: VSMCs were cultured by explant method. Cell proliferation model was established by stimulation with Ang II. Cell proliferation was measured by MTT assay to observe the effects of emodin (10, 20, 40 and 80 micromol x L(-1)) and N(G)-nitro-L-arginine methyl ester (L-NAME, 100 micromol x L(-1)) on VSMC proliferation induced by Ang II. The expression of PCNA was measured by immunohistochemical staining. Nitric oxide (NO) level was measured by Griess reagent. Nitric oxide synthase (NOS) and inducible nitric oxide synthase (iNOS) levels were detected by chemical colorimetric method. mRNA expression of iNOS was measured by reverse transcription polymerase chain reaction (RT-PCR). RESULT: Emodin at the doses range from 10 to 80 mol x L(-1) inhibited cell proliferation in a dose and time-dependent manner. The inhibitory effects were partly blocked by 100 mol x L(-1) of L-NAME. Emodin markedly decreased the expression of PCNA in VSMC, increased NO, NOS and iNOS levels, and increased iNOS mRNA expression in VSMC. CONCLUSION: Emodin could inhibite VSMCs proliferation induced by Ang II. Inhibiting the expression of PCNA, increasing the NO secretion and upregulating the iNOS gene expression might be associated with the inhibitory effects.

Inhibitory effects of emodin on the proliferation of cultured rat vascular smooth muscle cell-induced by angiotensin II.

Rhubarb, used as a traditional Chinese medicine for centuries, offers therapeutic potential for cardiovascular and other diseases. Emodin, extracted from the root extract of rhubarb has sparked increasing interest for therapeutic application. The main objective was to study the effect of emodin on cultured vascular smooth muscle cells (VSMCs) proliferation induced by angiotensin II (Ang II) and the expression of proto-oncogene c-myc. VSMCs were cultured by the explant method, then incubated for 24, 48 and 72 h with emodin (10-80 microm) and Ang II, or were left untreated (control). Cell proliferation was measured by MTT assay and immunohistochemical staining for proliferating cell nuclear antigen (PCNA), respectively. The expression of c-myc was measured by immunohistochemical staining and image analysis technique. Ang II increased the cell proliferation compared with the control group (p < 0.01). The expression of PCNA and c-myc was increased compared with the control group (p < 0.01). After pretreatment with emodin, the above indexes were obviously reduced compared with the Ang II group (p < 0.01). These findings suggested that emodin inhibited VSMCs proliferation induced by Ang II. Inhibition of the expression of c-myc might be correlated with the inhibitory effects.

Inhibition of vascular smooth muscle cell proliferation by serum from rats treated orally with Gastrodia and Uncaria decoction, a traditional Chinese formulation.

AIM: This study was to investigate the effect of serum from rats treated orally with GUD on vascular smooth muscle cells (VSMCs) proliferation in vitro. METHODS: Cell proliferation was measured by Methyl thiazolyl tetrazolium (MTT) assay. Expression of proliferating cell nuclear antigen (PCNA) and proto-oncogene c-myc were measured by immunochemical staining and image analysis. Griess reagent were used to detect nitric oxide (NO) level. Endothelin-1 (ET-1) level was measured by radioimmunoassay. RESULTS: GUD serum (2.5%-10%) inhibited VSMCs proliferation in a dose and time-dependent manner. GUD serum inhibited the expression of PCNA and c-myc. Moreover, GUD serum increased nitric oxide (NO), and decreased Endothelin-1 (ET-1) level in culture medium. CONCLUSION: GUD serum exhibited directly inhibitory effect in VSMCs proliferation. Inhibiting the expression of PCNA and c-myc, increasing NO level and decreasing ET-1 level might be associated with the antiproliferative effect.

[Effects of intercropping peanut with medicinal plants on soil microbial community].

With pot experiment, this paper studied the quantitative variations of bacteria, actinomyces, mould and yeast in soils of peanut intercropped with medicinal plants, aimed to test if such an intercropping pattern could remove the obstacles of peanut's continuous cropping. The results showed that Atractylodes lancea and Euphorbia pekinensis had the strongest inhibitory effect on mould. Compared with CK (mono-cropping peanut), the CFU of mould in the treatments intercropped with A. lancea and E. pekinensis was decreased by 53.87% and 29.59%, respectively during flowering-pegging stage of peanut, but increased after harvesting, which was in favor of substance circulation and nutrient returning. The CFU of bacteria in treatments intercropped with A. lancea, E. pekinensis and Pinellia ternate was all increased, and that of yeast in all five intercropping treatments was increased during the flowering-pegging stage of peanut. No familiar pathogens were found in the treatments intercropped with A. lancea, E. pekinensis and Diosoren zingiberebsis. Peanut intercropped with medicinal plants could regulate soil microbial community effectively.

A single pulmonary vein as electrophysiological substrate of paroxysmal atrial fibrillation.

INTRODUCTION: It has been demonstrated that pulmonary veins (PVs) play an important role in initiation and maintenance of paroxysmal atrial fibrillation (AF). However, it is not clearly known whether a single PV acts as electrophysiological substrate for paroxysmal AF. METHODS AND RESULTS: This study included five patients with paroxysmal AF. All patients underwent complete PV isolation with continuous circular lesions (CCLs) around the ipsilateral PVs guided by a three-dimensional mapping system. Irrigated radiofrequency (RF) delivery was performed during AF on the right-sided CCLs in two patients and on the left-sided CCLs in three patients. The incomplete CCLs resulted in a change from AF to atrial tachycardia (AT), which presented with an identical atrial activation sequence and P wave morphology. Complete CCLs resulted in AF termination with persistent PV tachyarrhythmias within the isolated PV in all five patients. PV tachyarrhythmia within the isolated PV was PV fibrillation from the left common PV (LCPV) in two patients, PV tachycardia from the right superior PV (RSPV) in two patients, and from the left superior PV in one patient. All sustained PV tachyarrhythmias persisted for more than 30 minutes, needed external cardioversion for termination in four patients and a focal ablation in one patient. After the initial procedure, an AT from the RSPV occurred in a patient with PV fibrillation within the LCPV, and was successfully ablated. CONCLUSION: In patients with paroxysmal AF, sustained PV tachyarrhythmias from a single PV can perpetuate AF. Complete isolation of all PV may provide good clinical outcome during long-term follow-up.

[Effects of Ginkgo biloba extract on number and activity of endothelial progenitor cells from peripheral blood].

AIM: To investigate whether Ginkgo biloba extract can augment endothelial progenitor cell (EPC) number, and promote EPC proliferation, migration and adhesion. METHODS: Total mononuclear cells (MNCs) were isolated from peripheral blood by Ficoll density gradient centrifugation, and then the cells were plated on fibronectin-coated culture dishes. After 7 days of culture, attached cells were stimulated with Ginkgo biloba extract (10, 25 and 50 mg x L(-1)) or vehicle control for the respective time points (6, 12, 24 and 48 h). EPC were characterized as adherent cells double positive for DiLDL-uptake and lectin binding by direct fluorescent staining under a laser scanning confocal microscope. EPC were further documented by demonstrating the expression of CD34, VEGFR-2 and AC133 with flow cytometry. EPC proliferation, migration and in vitro vasculogenesis activity were assayed with MTT assay, modified Boyden chamber assay and in vitro vasculogenesis kit, respectively. EPCs adhesion assay was performed by replating MNCs on fibronectin-coated dishes, and then counting adherent cells. RESULTS: Incubation of isolated human MNCs with Ginkgo biloba extract increased the number of EPC, maximum at 25 mg x L(-1), 24 hours (approximately 1-fold increase, P < 0.01). In addition, Ginkgo biloba extract promotes EPC proliferative, migratory, adhesive and in vitro vasculogenesis capacity. CONCLUSION: Ginkgo biloba may promote EPC augmentation and enhance its functional activity.

[Effects of puerarin on number and activity of endothelial progenitor cells from peripheral blood].

OBJECTIVE: To investigate whether puerarin can augment endothelial progenitor cells (EPCs) numbers, promote EPC proliferation, migration and adhesion. METHOD: Total mononuclear cells (MNCs) were isolated from peripheral blood by Ficoll density gradient centrifugation, and then the cells were plated on fibronectin-coated culture dishes. After 7 days culture, attached cells were stimulated with puerarin (to make a series of final concentrations: 0. 1, 0.5, 1, 3 mmol x L(-1)) or vehicle control for the respective time points (6, 12, 24, 48 h). EPCs were characterized as adherent cells double positive for DiLDL-uptake and lectin binding by direct fluorescent staining under a laser scanning confocal microscope. EPCs proliferation, migration and in vitro vasculogenesis activity were assayed with MT assay, modified Boyden chamber assay and in vitro vasculogenesis kit, respectively. EPCs adhesion assay was performed by replating those on fibronectin-coated dishes, then adherent cells were counted. RESULT: Incubation of isolated human MNCs with puerarin dose increased the number of EPCs, maximum at 3 mmol x L(-1), 24 hours (approximately 1-fold increase, P < 0.01). In addition, puerarin also promoted EPC proliferative, migratory, adhesive and in vitro vasculogenesis capacity. CONCLUSION: Puerarin can augment the number of EPCs with enhanced functional activity.

Effects of Ginkgo biloba extract on number and activity of endothelial progenitor cells from peripheral blood.

The aim of this study is to investigate whether Ginkgo biloba extract can augment endothelial progenitor cells numbers, and promote the cells' proliferative, migratory, adhesive, and in vitro vasculogenesis capacity. Total mononuclear cells were isolated from peripheral blood by Ficoll density gradient centrifugation, and then the cells were plated on fibronectin-coated culture dishes. After 7 days culture, attached cells were stimulated with Ginkgo biloba extract (to make a series of final concentrations: 10 mg/L, 25 mg/L, and 50 mg/L) or vehicle control for the respective time points (6 hours, 12 hours, 24 hours, and 48 h). Endothelial progenitor cells were characterized as adherent cells double positive for DiLDL-uptake and lectin binding by direct fluorescent staining under a laser scanning confocal microscope. They were further documented by demonstrating the expression of KDR, VEGFR-2, and AC133 with flow cytometry. Endothelial progenitor cells proliferation, migration, and in vitro vasculogenesis activity were assayed with 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay, modified Boyden chamber assay, and in vitro vasculogenesis kit, respectively. Endothelial progenitor cells adhesion assay was performed by replating those on fibronectin-coated dishes, and then counting adherent cells. Incubation of isolated human mononuclear cells with Ginkgo biloba extract dose- and time-dependently increased the number of endothelial progenitor cells, maximum at 25 mg/L, 24 hours (approximately 1-fold increase, P < 0.01). In addition, Ginkgo biloba extract also dose- and time-dependently promoted endothelial progenitor cells proliferative, migratory, adhesive, and in vitro vasculogenesis capacity. The results of the present study defined a novel functional effect of Ginkgo biloba extract: the augmentation of endothelial progenitor cells with enhanced functional activity.

[Nutrient and water cycling in red soils with different planting system and their management].

Based on the data of long term located experiment, this paper studied the characteristics of nutrient and water cycling and balance and of energy flow in upland red soils with different planting system. The results showed that in red soil areas, the rainfall from March to June accounted for 60% of the whole year, which induced frequent seasonal drought and severe water and soil loss. The application of N, P and K on upland red soil was overabundant and unbalanced, which induced a reduced ratio of input and output. Optimized planting mode could increase the water and light utilization efficiency, decrease the frequency and degree of occurred drought, and increase the nutrient recycling rate. The main measures for rationally developing and utilizing red soil should be establishing compound agro-ecosystem model of planting and feeding, saving irrigation water, increasing mulch, cover-cultivating crops and forests, increasing the proportion of organic fertilizer, realizing rational and balanced fertilization, further optimizing planting structure, regulating energy input structure, and adopting multilevel-technologies of food chain utilization.