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The use of straw returning plus nitrogen fertilizer on farmland is one of the important agronomic practices for adjusting soil organic carbon (SOC) transformations. To explore the mechanisms of straw and nitrogen fertilizer application on straw and SOC mineralization in long-term fertilized soils, an incubation experiment with the 13 C isotope tracing technique was conducted, which involved three long-term fertilized models in typical karst soils (no fertilization, inorganic fertilization, and a combination of inorganic fertilization and straw). To study the mechanisms of 13 C-labeled straw and SOC mineralization, four treatments were designed as follows:no straw and nitrogen (control), and straw combined with three levels of nitrogen fertilizer (0, 214.0, and 571.0 mg·kg -1 soil). The results showed that cumulative mineralization amounts of straw-derived organic carbon in long-term fertilized soils were markedly higher than those in non-fertilized soil. Straw-derived organic carbon mineralization was significantly affected by nitrogen fertilizer levels. The positive priming effects (PE) in long-term fertilized soils were much lower than those in non-fertilized soil. The PE was decreased at the low nitrogen fertilizer level but increased at the high nitrogen fertilizer level. The principal component analysis (PCA) of phospholipid fatty acids (PLFAs) indicated that the soil microbial community structure was greatly affected by the long-term fertilization models and combined straw and nitrogen fertilizer application. Moreover, the content of PLFAs in soil microorganisms, namely, bacteria and fungi, were remarkably increased by the straw plus nitrogen fertilizer (values increased by 40.3%-53.0%, 41.1%-62.6%, and 60.5%-148.6% compared with control), but levels were not significantly affected by nitrogen fertilizer levels alone. The ratios between PLFAs of soil gram-positive and gram-negative bacteria (G + /G - ) decreased and were stable at around 0.8. The structure equation models (SEM) demonstrated that the combination of straw and nitrogen affected the soil gram-positive and gram-negative bacteria structure and increased the soil DOC content, which promoted the decomposition of straw and affected the mineralization of SOC. These results indicate that straw returning plus low nitrogen fertilizer can improve the SOC sequestration capacity in karst farmland.

To study the effects of ellagic acid(EA)on inflammation and oxidative stress in mice with fatty liver disease induced by AKT gene transfection,the 20 female FVB mice were randomly divided into normal control group,model group and ellagic acid administration group(150,300 mg·kg~(-1)·d~(-1))(n=5).EA experimental groups and model group were using a high pressure into the tail vein transfection plasmid AKT.The next day,EA was started to administered continuously for 5 weeks after the AKT gene transfection,while the model group and the normal control group were given the same amount of saline.After the administration,the liver tissue and serum of mice were taken.HE and oil red O staining were using to observe the histopathological changes in liver;liver function to detect the serum and liver tissue as well as MDA and SOD levels;real-time quantitative PCR(RT-qPCR)was used to measure the mR-NA expression of NF-κB and TNF-α;Western blot and immunohistochemistry were used to measure the expression of NF-κB,TNF-αand COX-2 in liver tissue.RESULTS:: show that after AKT gene transfection,the model group had significant increase in the serum levels of AST,ALT,elevated the levels of MDA and decreased the levels of SOD in serum and liver tissue,aggravated histopathology degeneration and Liver inflammation,and significantly higher expression of NF-κB,TNF-α,IL-6,COX-2 and other inflammatory-related factors in liver tissue.EA administration group significant reductions in the serum levels of AST,ALT,and improved in hepatocyte fatty degeneration and liver inflammation,lower the levels of MDA and increased the levels of SOD in serum and liver tissue,and significant reductions in the expression of NF-κB,TNF-α,IL-6 and COX-2 in liver tissue.These results suggest that EA has obvious anti-inflammatory effect and inhibits oxidative stress and EA has a significant therapeutic effecton AKT gene inducing fatty liver,and the mechanism possibly by inhibiting inflammatory factors of NF-κB,TNF-α,IL-6,COX-2 and anti-oxidative stress-related.

In order to understand the influence of environmental factors on the carbonate conversion of the Karst soil, typical brown limestone and red soil samples were collected from the Karst ecosystem, and a 100-day incubation experiment was conducted. The characteristics of inorganic carbon release from the soil under three temperature gradients (15, 25, and 35℃) and water contents (30%, 65%, and 100% WHC) were studied by adding 14 C-CaCO 3 for 100 d. The results showed that under the different soil moisture and temperature conditions, the maximum rate and the cumulative amount of inorganic carbon release from the soil over 100 days varied between 0.7-16.8 mg·(kg·d) -1 and 5.9-29.4 mg·kg -1 , respectively, in the brown limestone soil, and varied between 39.7-103.3 mg·(kg·d) -1 and 83.3-135.1 mg·kg -1 , respectively in the red soil. Under drought conditions (30% WHC), the cumulative amount of inorganic carbon release was the highest for the two soils and increased with increasing temperature. At 65% WHC and 100% WHC, increasing temperature can still promote inorganic carbon release from the soil. The temperature sensitivity of the soil inorganic carbon release in the brown limestone soil is greater than that of the red soil, which is significantly affected by soil moisture. The soil pH and MBC content were remarkably increased after adding CaCO 3 , and the difference between the two soils was significant. The variance partition showed that temperature and soil moisture can explain 7.6% and 2.0% of the soil inorganic carbon release variability, respectively. In conclusion, warming and drought aggravate inorganic carbon release from brown limestone soil in the southwestern Karst region. Therefore, in the context of global warming and more frequent extreme precipitation events, the effects of soil moisture and temperature on inorganic carbon conversion in soil should be fully considered when studying the soil carbon cycle and its dynamic changes in southwestern Karst. This research can provide a scientific basis for further understanding the influence of climate change on the global carbon cycle.

Objective: To study the chemical constituents of the ethyl ether extract of the Leptopus chineseis., Methods: The chemical constituents were isolated by means of chromatography and identified by spectra data and physicochemical characters., Results: Three compounds were isolated and identified as friedelane-2alpha, 3beta-diols (1), betulinic acid (2) and 3beta-O-trans-coumaroylbetulinic acid (3)., Conclusion: The compounds are isolated from Leptopus chineseis for the first time.

Objective: To investigate the aging features of pure leukoaraiosis (LA) in non-demented outpatients., Methods: The outpatients with age older than 40 years, without taking cholesterol lowering and B vitamin medications and with mini-mental state examination more than 24 scores were selected from July 2008 to December. 2009 in Beijing Tiantan Hospital. LA was defined with MRI. Patients were classified into two groups i.e. LA group consisting of 138 patients with leukoaraiosis but without lacunar lesions and cortical infarcts and a control group consisting of 124 patients without any lesion in brain. Age and other vascular risk factors were also investigated., Results: Age of the patients in the LA group was significantly higher than that in the control group (P<0.001). Multivariable logistic regression analysis showed that age was independently associated with pure LA (OR 1.080, 95%CI 1.042-1.120), after adjusting sex, vascular risk factors and presence of atherosclerosis in cervical arteries. If age-stratification was further considered, logistic regression analysis showed that OR (95%CI) for LA was 2.693 (95%CI 1.103-6.575) in a 60-69 year group and 13.527 (95%CI 3.319-55.131) in a ≥70 year group as compared with a 40-49 year group., Conclusion: Age is a determining risk factor for pure LA and patients with age older than 60 years are at high risk of LA.

Objective: To identify whether high level of plasma homocysteine is an independent risk factor for potential cerebral large-artery atherosclerotic stenosis determined by digital subtraction angiography (DSA) in patients with ischemic stroke., Methods: 276 adult patients with ischemic stroke experienced DSA were selected, and 224 patients with potential large-artery atherosclerotic stenosis (grade > 50%, not less than one of vascular) and 52 controls without stenosis or mild grade (grade < or = 50%) were included. Plasma homocysteine level was analyzed and conventional risk factors of cerebral stroke such as sex and age, hypertension, diabetes, long-smoking, long-alcohol and plasma levels of triglyceride, high-density lipoprotein, low-density lipoprotein was evaluated in 276 subjects., Results: The proportion of subjects with high level of plasma homocysteine (> 15 micromol/L) was significantly higher in patients with potential atherosclerotic stenosis than those without (38.8% versus 15.4%; OR 3.49, 95% CI 1.57 - 7.77, P = 0.001). Based on multivariable stepwise logistic regression model, the odds ratio of homocysteine levels was 4.10 (95% CI 1.80 - 9.32, P = 0.001) with additional adjustment for conventional risk factors. The effect of homocysteine was more pronounced in the presence of hypertension (OR = 4.89), old age (OR = 4.79) and low level of plasma high density lipoprotein (OR = 10.46)., Conclusions: It is suggested that high level of plasma homocysteine is an independent risk factor for cerebral large-artery atherosclerosis. The effect of homocysteine is more pronounced in the presence of other risk factors of ischemic stroke.

Objective: To assess the safety and efficacy of stent-assisted angioplasty (SAA) for symptomatic intracranial artery stenosis, and to evaluate preliminarily the significance of classification of location, morphology and access (LMA classification) of intracranial artery stenosis in SAA., Methods: Forty-two patients with symptomatic intracranial artery stenosis (diameter reduction: 50% - 74%, n = 15; >or= 75%, n = 27), located in middle cerebral artery (n = 27), intracranial internal carotid artery (n = 4), intracranial vertebral artery (n = 7) and basilar artery (n = 4) respectively, refractory to medical therapy were enrolled in this study., Results: LMA classification: 23 of the forty-two lesions (54.8%) located at the site of bifurcation, which were classified according to the location into type A (n = 8), B (n = 11), C (n = 2), D (n = 1) and F (n = 1) respectively. Type A, B and C lesions were 19, 19 and 4 respectively in the light of morphologic classification. Type I, II and III accesses were 15, 23 and 4 respectively in the light of access classification., Technique: The technical successful rate of SAA was 95.2% (40/42) for the group overall, and 100% (15/15), 94.7% (22/23), and 75% (3/4) for type I, II, III accesses, respectively. The rate of periprocedural complication and death was 9.5% (4/42), including acute occlusion (n = 1) and high perfusion syndrome (n = 3). After emergency measures, 3 patients were cured completely, and the remaining one with severe MCA trunk stenosis of type C lesion died of subarachnoid hemorrhage (2.4%). During a clinical follow-up period ranging from 1 to 18 months (median 8 months), 39 patients receiving SAA have been still free from ischemic events. There was no restenosisfound angiographically 6 months (n = 7) and 12 months (n = 4) after SAA., Conclusions: Our results suggest that under rigorous control of procedural and periprocedural measures, SAA appears to be a safe and effective therapy for symptomatic intracranial stenoses of type A and B lesions, but it is not risk-free for type C lesions. The LMA classification is helpful for predicting the results of SAA and to design the procedure. However, further study is needed.