[Virtual screening of components of safflower against myocardial ischemia based on molecular docking technology].

The screening of active components of traditional Chinese medicine has always been the focus and difficulty in modern research of Chinese medicine preparations. With the continuous development of life science, omics and computer technology, the virtual screening technology for active components of traditional Chinese medicine has gradually come into people's vision. Molecular docking technology is an important method for screening active components of traditional Chinese medicine. It not only has a short cycle and strong operability, but also avoids the disadvantage of poor stability in pharmacological experiments. Safflower extract can effectively alleviate the symptoms of myocardial ischemia, but its active components are not clear. In this study, with use of the molecular docking technology, the active components in safflower against myocardial ischemic were virtually screened based on the screening method of active components. Forty-six chemical components and 5 target proteins which showed high correlation with myocardial ischemia were obtained from the existing database and related literature reports. With the molecules of three commercially available drugs diltiazem, trimetazidine and verapamil as positive control molecules, the compomnents were docked with 5 target proteins. Active components were screened according to docking scores and interactions between molecules and targets, and then the active ingredients can be inferred. Fourteen chemical components were screened to have the most potential anti-myocardial ischemic activity, and all of them were flavonoids. Therefore, it can be inferred that the flavonoid components are the most potential anti-myocardial ischemic components in safflower. The screening of active anti-myocardial ischemia components in safflower was completed in this study, laying the foundation for subsequent researches.

Meta-transcriptomic analysis reveals a new subtype of genotype 3 avian hepatitis E virus in chicken flocks with high mortality in Guangdong, China.

BACKGROUND: Hepatitis E virus (HEV) is one of most important zoonotic viruses, and it can infect a wide range of host species. Avian HEV has been identified as the aetiological agent of big liver and spleen disease or hepatitis-splenomegaly syndrome in chickens. HEV infection is common among chicken flocks in China, and there are currently no practical measures for preventing the spread of the disease. The predominant avian HEV genotype circulating in China have been identified as genotype 3 strains, although some novel genotypes have also been identified from chicken flocks in China. RESULTS: In this study, we used a meta-transcriptomics approach to identify a new subtype of genotype 3 avian HEV in broiler chickens at a poultry farm located in Shenzhen, Guangdong Province, China. The complete genome sequence of the avian HEV, designated CaHEV-GDSZ01, is 6655-nt long, including a 5' UTR of 24 nt and a 3' UTR of 125 nt (excluding the poly(A) tail), and contains three open reading frames (ORFs). Sequence analysis indicated that the complete ORF1 (4599 nt/1532 aa), ORF2 (1821 nt/606 aa) and ORF3 (264 nt/87 aa) of CaHEV-GDSZ01 share the highest nucleotide sequence identity (85.8, 86.7 and 95.8%, respectively) with the corresponding ORFs of genotype 3 avian HEV. Phylogenetic analyses further demonstrated that the avian HEV identified in this study is a new subtype of genotype 3 avian HEV. CONCLUSIONS: Our results demonstrate that a new subtype of genotype 3 avian HEV is endemic in Guangdong, China, and could cause high mortality in infected chickens. This study also provides full genomic data for better understanding the evolutionary relationships of avian HEV circulating in China. Altogether, the results presented in this study suggest that more attention should be paid to avian HEV and its potential disease manifestation.

Molecular characterization of two novel reoviruses isolated from Muscovy ducklings in Guangdong, China.

BACKGROUND: Novel Muscovy duck reovirus (N-MDRV), emerged in southeast China in 2002, which can infect a wide range of waterfowl and induces clinical signs and cytopathic effects that are distinct from those of classical MDRV, and continues to cause high morbidity and 5-50% mortality in ducklings. The present study aimed to investigate the characteristics of two novel reoviruses isolated from Muscovy ducklings in Guangdong, China. RESULTS: Two novel MDRV strains, designated as MDRV-SH12 and MDRV-DH13, were isolated from two diseased Muscovy ducklings in Guangdong province, China in June 2012 and September 2013, respectively. Sequencing of the complete genomes of these two viruses showed that they consisted of 23,418 bp and were divided into 10 segments, ranging from 1191 bp (S4) to 3959 bp (L1) in length, and all segments contained conserved sequences in the 5' non-coding region (GCUUUU) and 3' non-coding region (UCAUC). Pairwise sequence comparisons demonstrated that MDRV-SH12 and MDRV-DH13 showed the highest similarity with novel MDRVs. Phylogenetic analyses of the nucleotide sequences of all 10 segments revealed that MDRV-SH12 and MDRV-DH13 were clustered together with other novel waterfowl-origin reoviruses and were distinct from classical waterfowl-origin and chicken-origin reoviruses. The analyses also showed possible genetic re-assortment events in segment M2 between waterfowl-origin and chicken-origin reoviruses and the segments encoding λA, µA, µNS, σA, and σNS between classical and novel waterfowl-origin reoviruses. Potential recombination events detection in segment S2 suggests that MDRV-SH12 and MDRV-DH13 may be recombinants of classical and novel WRVs. CONCLUSIONS: The results presented in this study, the full genomic data for two novel MDRV strains, will improve our understanding of the evolutionary relationships among the waterfowl-origin reoviruses circulating in China, and may aid in the development of more effective vaccines against various waterfowl-origin reoviruses.

[Effect of GnRHa controlled ovarian hyperstimulation on mouse embryo implantation and its mechanism].

The purpose of the present study was to investigate the effects and underlying mechanism of gonadotropin-releasing hormone agonist (GnRHa) controlled ovarian hyperstimulation (COH) on embryo implantation in mice. Forty female Kunming mice aged 9 weeks were randomly divided into two groups (control and COH groups). The COH group received intraperitoneal (i.p.) injections of aminocyclin acetate (GnRHa), human menopausal gonadotropin (HMG) and human chorionic gonadotropin (hCG), while the control group was given equal amount of physiological saline by i.p. injection. One male mouse and two female mice were put into the same cage at 16:00 on the hCG injection day, and on the fourth day of pregnancy, 10 mice from each group were killed. The levels of serum estradiol (E2) and progesterone (P) were measured by radioimmunoassay; HE staining was used to observe the morphology of ovarian and endometrial tissues. The protein expression levels of endometrial leukemia inhibitory factor (LIF), phosphorylated signal transducer and activator of transcription 3 (p-STAT3), heparin-binding epidermal growth factor-like growth factor (HB-EGF) and glycodelin A were detected by Western blot and immunohistochemistry. Ten mice from each group were sacrificed on the eighth day of pregnancy, and the status of the uterus and the average number of blastocysts were observed. The results showed that, compared with control group, the serum E2 level in COH group was significantly decreased (P < 0.05), while the P level was increased significantly (P < 0.05); the ovarian follicles at different developmental stages were rare, corpus lutea (CL) were visible and multiple, the endometrium was thinned, and the number of endometrial glands was reduced (P < 0.05); the contents of LIF, p-STAT3, HB-EGF and glycodelin A in the endometrium were decreased significantly (P < 0.05) on the fourth day of pregnancy; mouse blastocysts developed slowly and were decreased in number on the eighth day of pregnancy (P < 0.05). The above results suggest that GnRHa COH can affect embryo implantation in mice. The mechanism may be related to the imbalance of gonadal hormone, the changes in the structure of the endometrium and the expressions of LIF, p-STAT3, HB-EGF and glycodelin A in the implantation stage, which may lead to the decrease of endometrial receptivity and the abnormal dialogue between the embryo and the uterus.

Tunable optofluidic microring laser based on a tapered hollow core microstructured optical fiber.

A tunable optofluidic microring dye laser within a tapered hollow core microstructured optical fiber was demonstrated. The fiber core was filled with a microfluidic gain medium plug and axially pumped by a nanosecond pulse laser at 532 nm. Strong radial emission and low-threshold lasing (16 nJ/pulse) were achieved. Lasing was achieved around the surface of the microfluidic plug. Laser emission was tuned by changing the liquid surface location along the tapered fiber. The possibility of developing a tunable laser within the tapered simplified hollow core microstructured optical fiber presents opportunities for developing liquid surface position sensors and biomedical analysis.

Combination of specific single chain antibody variable fragment and siRNA has a synergistic inhibitory effect on the propagation of avian influenza virus H5N1 in chicken cells.

BACKGROUND: The avian influenza virus (AIV) causes frequent disease with high morbidity and mortality. RNA interference (RNAi) has been shown to provide an effective antiviral defense in animals, and several studies have focused on harnessing small interfering RNAs (siRNAs) to inhibit viral infections. In addition, single chain variable fragments (scFvs) contain the complete antigen binding site, and specific scFvs can bind to and neutralize viruses. RESULTS: Fourteen positive scFvs were selected by the yeast two-hybrid system. Using molecular docking technology, we selected the three highest affinity scFvs for further functional validation. Results of indirect ELISA and IFA showed that all three scFvs could bind to FJ13 strain and had neutralizing activity, decreasing the viral infectivity markedly. Chicken fibroblastic DF-1 cells were transfected with scFvs in combination with siRNA-NP604 (an siRNA of anti-AIV NP protein previously reported). Following infection with FJ13 virus, copy numbers of the virus were significantly reduced from 12 h to at least 60 h post-infection compared to that achieved in cells transfected with scFv or siRNA-NP604 separately. CONCLUSIONS: A novel combination of antiviral siRNAs expressed in chicken cells and chicken antibody single-chain variable fragments (scFvs) secreted from the cells has a synergistic inhibitory effect on the avian influenza viral proliferation in vitro. Intracellular application of scFvs and anti-viral siRNA may provide a new approach to influenza prevention and treatment.

Complete genome sequence of novel porcine epidemic diarrhea virus strain GD-1 in China.

Porcine epidemic diarrhea virus (PEDV) infection, which causes acute diarrhea and dehydration in suckling piglets, has become a serious problem for the swine industry of China in recent years. In this study, a virulent PEDV strain, GD-1, was obtained from fecal samples from suckling piglets that suffered from severe diarrhea in 2011 in Guangdong, China. Here we describe the complete genome sequence of strain GD-1, which may be helpful in further understanding the molecular epidemiology and genetic diversity of PEDV field isolates in China.

Effect of simulated microgravity and its associated mechanism on pulmonary circulation in rats.

OBJECTIVE: To study the effect of Simulated Microgravity and its Associated Mechanism on Pulmonary Circulation in Rats). METHODS: Rat tail-suspension model was used to simulate the physiological effects of microgravity and changes in pulmonary blood vessel morphology, pulmonary arterial and venous blood pressure, pulmonary vascular resistance, pulmonary vasomotoricity, as well as the regulation of pulmonary circulation by cytokines produced and released by the lung of rats were measured. RESULTS: The walls of pulmonary blood vessels of rats were thickened, and the pulmonary artery was reconstructed with increased pulmonary vascular resistance. The pulmonary blood vessels of rats became more prone to dilation as contractions increased. Rat epithelial Adrenomedulin gene transcription and protein expression were upregulated. The level of basic fibroblast growth Factor of rat was also elevated. CONCLUSION: Findings from the present study on rats revealed that the microgravity can affect pulmonary blood vessel structure, pulmonary arterial pressure, and pulmonary blood vessel self-regulation and cytokine production.

Seasonal dynamics of soil nitrogen mineralization and their influencing factors during shrub anthropogenic introduction in desert steppe.

We selected enclosed grassland, grazed grassland and shrublands with different planting years (3, 12, 22 years)/densities (intervals of 2, 6, 40 m) to investigate soil N mineralization dynamics in the growing season (April-October) and its influencing factors during the process of desert steppe-degradation-shrub introduction. The results showed that soil moisture at 0-200 cm layer was decreased with increases of shrub age and density, and that the variations of soil moisture at 0-10 cm layer coincided with seasonal change. Compared with grazed grassland and enclosed grassland, the positive effect of shrubs on soil carbon, nitrogen and phosphorus contents first increased and then decreased with the increases of age and density. Moreover, soil N mineralization significantly varied across months and sites. Soil NO3- content and microbial biomass carbon and nitrogen were significantly higher from June to August. The proportion of NO3- to inorganic nitrogen significantly increased from 30.5% in enclosed grassland to 69.5% in shrublands. NH4+ content was mainly affected by months compared with sites. In the process of steppe-degradation-shrub introduction, the increases of shrub age and density significantly enhanced seasonal differences of soil nitrification and ammonification, but not on the seasonal mineralization of microbial biomass carbon and nitrogen. Soil NH4+ and NO3- contents were significantly and positively correlated with total nitrogen, organic carbon and N/P. Soil stoichiometric ratios (C/N and N/P) directly regulated N mineralization process.

Progress in diagnosis and treatment of acute injury to the anterior talofibular ligament.

Injury to the anterior talofibular ligament (ATFL) is a common acute injury of the lateral foot ligament. Untimely and improper treatment significantly affects the quality of life and rehabilitation progress of patients. The purpose of this paper is to review the anatomy and the current methods of diagnosis and treatment of acute injury to the ATFL. The clinical manifestations of acute injury to the ATFL include pain, swelling, and dysfunction. At present, non-surgical treatment is the first choice for acute injury of the ATFL. The standard treatment strategy involves the "peace and love" principle. After initial treatment in the acute phase, personalized rehabilitation training programs can be followed. These may involve proprioception training, muscle training, and functional exercise to restore limb coordination and muscle strength. Static stretching and other techniques to loosen joints, acupuncture, moxibustion massage, and other traditional medical treatments can relieve pain, restore range of motion, and prevent joint stiffness. If the non-surgical treatment is not ideal or fails, surgical treatment is feasible. Currently, arthroscopic anatomical repair or anatomical reconstruction surgery is commonly used in clinical practice. Although open Broström surgery provides good results, the modified arthroscopic Broström surgery has many advantages, such as less trauma, rapid pain relief, rapid postoperative recovery, and fewer complications, and is more popular with patients. In general, when treating acute injury to the ATFL, treatment management and methods should be timely and reasonably arranged according to the specific injury scenario and attention should be paid to the timely combination of multiple therapies to achieve the best treatment results.

Preoperative prediction of vessel invasion in locally advanced gastric cancer based on computed tomography radiomics and machine learning.

Vessel invasion (VI) is an important factor affecting the prognosis of gastric cancer (GC), and the accurate determination of preoperative VI for locally advanced GC is of great clinical significance. Traditional methods for the evaluation of VI require postoperative pathological examination. Noninvasive preoperative evaluation of VI is therefore crucial to determine the best treatment strategy. To determine the value of preoperative prediction of gastric VI based on portal venous phase computed tomography (CT) radiomic features and machine-learning models, a retrospective analysis of 296 patients with locally advanced GC confirmed through pathological examination was performed. They were divided into two groups, VI+ (n=213) and VI- (n=83), based on pathological results. Using pyradiomics to extract two-dimensional radiomic features of the portal venous stage of locally advanced GC, data were divided into training (n=207) and validation sets (n=89), with a ratio of 7:3, and three feature selection methods were cascaded and merged. Finally, least absolute shrinkage and selection operator (LASSO) regression was used for feature screening to obtain the optimal feature subset. Four current representative machine-learning algorithms were used to construct the prediction model, the receiver operating characteristic curve was constructed to evaluate the predictive performance of the model, and the area under the curve (AUC), accuracy, sensitivity, and specificity were calculated. The differentiation degree, and the Lauren's and CA199 classifications were independent risk factors for locally advanced GC VI. Pyradiomics extracted 864 quantitative features of portal vein images of locally advanced GC. After filtering out low variance features using R, 236 features remained. Next, 18 features were screened using the LASSO algorithm. Extreme gradient boosting (XGBoost), logistic regression, Gaussian naive Bayes, and support vector machine models were constructed based on the 18 best features screened out of the portal venous CT images of advanced GC and three independent risk factors of GC VI in clinical features predicted the training set AUC values of 0.914, 0.897, 0.880, and 0.814, respectively. The predicted validation set AUC values were 0.870, 0.877, 0.859, and 0.773, respectively. The DeLong test results indicated no statistically significant difference in AUC values between the XGBoost and logistic regression models in the training and validation sets. The four machine-learning models showed high predictive performance. The logistic regression model had the highest AUC value in the validation set (0.877), and the accuracy and F1 score were 77 and 87.6%, respectively. CT radiomic features and machine-learning models based on the portal venous phase can be used as a noninvasive imaging method for the preoperative prediction of VI in locally advanced GC. The logistic regression model exhibited the highest diagnostic performance.

Molecular characterization and phylogenetic analysis of porcine epidemic diarrhea virus (PEDV) field strains in south China.

A total of 127 porcine samples were collected from 48 farms in six provinces in south China. The positive rate of porcine epidemic diarrhea virus (PEDV) was 43.0 % (55/127), and the co-infection rate of PEDV and transmissible gastroenteritis virus (TGEV) was 12.0 % (15/127). The partial S gene and complete M gene were amplified from PEDV-positive strains by RT-PCR, cloned, sequenced and compared with each other, as well as with the reference strains in GenBank. Sequence homology results of the partial S gene and complete M gene showed that all south China field PEDV strains had nucleotide (deduced amino acid) sequence identities of 86.7-98.7 % (83.2-99.3 %) and 96.1-100 % (95.0-100%), respectively, with the foreign reference strains reported in GenBank. Phylogenetic analysis of the partial S gene showed that all the south China PEDV strains and two Thailand strains (08UB01 and 08RB07) belong to the same group and differ genetically from European strains and early domestic strains. Phylogenetic analysis of the complete M gene showed that all south China PEDV strains have a close relationship with most of the strains in Korea and Thailand, but differ genetically from the vaccine strain (CV777).

[Responses of soil nitrogen to the transition from desert grassland to shrubland in eastern Ningxia, China]. / å®å¤ä¸œéƒ¨è’æ¼ è‰åŽŸ-çŒä¸›åœ°è½¬å˜è¿‡ç¨‹åœŸå£¤æ°®ç´ å“åº”.

In this study, desert grassland, grassland edge, shrubland edge, shrubland were selec-ted as four transition sites in a nearly 30 years typical desert grassland-shrubland mosaic formed by anthropogenic shrub introduction. Soil properties and soil microbial characteristics under vegetation patches and bare interspace in each site were investigated to examine the responses of soil nitrogen to the desert grassland-shrubland state transition. It was shown that the aboveground biomass increased with transition from desert grassland to shrubland. Annual herbs increased largely with the introduction of shrubs. Soil moisture, microbial biomass and total nitrogen and carbon decreased with the transition. The abundance of microogranisms was lower in grassland edge and shrubland edge, and then increased in shrubland, which was slightly higher than that of desert grassland. With respect to nitrogen, nitrate content reached the highest level of 28.45 mg N·kg-1 and ammonium reached the lowest level of 4.81 mg N·kg-1 in shrubland, which were significantly increased by 52.3% and decreased by 10.4% compared with desert grassland. In addition, soil moisture and microbial biomass nitrogen was positively correlated across all sites. The relationship between mine-ralized nitrogen and soil moisture was non-linear, as they were positively correlated in desert grassland and grassland edge, but negatively correlated in shrubland edge and shrubland. During the 30-year transition from desert grassland to shrubland, our results showed that soil total nitrogen and microbial biomass nitrogen were significantly decreased, but mineralized nitrogen, especially for nitrate, significantly increased over time, indicating that soil nitrification was inhibited in desert grassland but accelerated in shrubland.

Diagnostic value and potential clinical significance of duodenal lipoma based on computed tomography imaging data.

BACKGROUND: To explore the diagnostic value of computed tomography (CT) imaging for duodenal lipoma and the potential clinical significance of the findings. METHODS: Clinicopathological and CT data from 57 patients, who were diagnosed with duodenal lipoma at the first affiliated Hospital of Zhengzhou University (Zhengzhou, China) between June 2014 and March 2019, were retrospectively reviewed. Data collected included location and size of the tumor, morphological manifestations (shape, density, boundary), concomitant diseases, pathology and gastroscopy results, and follow-up. Follow-up was performed via telephone, and surgical patients were followed-up for recurrence, metastasis and tumor size, and morphological changes. The follow-up period was up to January 2019. RESULTS: Of the 57 patients with duodenal lipoma, contrast-enhanced scanning was performed in 7 cases. The tumor was located in the descending duodenum in 33 cases, the ascending in 4 cases, the horizontal in 16 cases, and the bulb in 4 cases. Mean tumor size was 13.0 ±â€Š5.8 mm. CT morphological features of the tumor were as follows: tumor shape, round, quasi-round, or oval (n = 42); long strip (n = 3); nodular (n = 2); triangular (n = 1); and irregular lobulated (n = 9). Among the 57 patients, tumor density was homogeneous in 52 cases, inhomogeneous in 4 cases, and nodular with calcification in 1 case. The tumor boundary was classified as clear and with no capsule. Diseases concomitant with the tumor were as follows: gastritis (n = 23), gastric adenocarcinoma (n = 1), and gastric lymphoma (n = 1). Esophageal disease was found in 16 cases, including reflux esophagitis (n = 12) and esophageal cancer (n = 4). There were 13 cases of gallbladder and biliary disease, including cholecystolithiasis and cholecystitis (n = 9), common bile duct disease (n = 2), colorectal cancer (n = 4), lung cancer (n = 2), duodenal carcinoma with obstruction (n = 1), and ureteral space narrowing (n = 1). CONCLUSION: CT was an effective, non-invasive method for diagnosis of duodenal lipoma. CT imaging could clearly discern location, size, shape, and nature of duodenal lipomas. Duodenal lipoma can be associated with digestive tract inflammatory diseases and tumors in different locations, and its diagnosis is potentially valuable for their prevention and treatment.

Public Awareness and Mask Usage during the COVID-19 Epidemic: A Survey by China CDC New Media.

An online survey conducted March 18-19, 2020 on the official China CDC WeChat account platform was used to evaluate the effect of public education about masks usage during the new coronavirus disease 2019 (COVID-19) epidemic. Chinese nationals older than 18 were eligible for the survey. The survey collected 5,761 questionnaires from the 31 provinces, municipalities, and autonomous regions of mainland China. 99.7% and 97.2% of the respondents answered correctly that respiratory droplets and direct contact were the main transmission routes. 73.3% of the respondents considered COVID-19 to be 'serious' or 'very serious'. When going to the hospital, 96.9% (2,885/2,976 had gone to a hospital) used a mask during the COVID-19 epidemic, while 41.1% (2,367/5,761) did not use a mask before the epidemic. Among the respondents that used public transportation and went shopping, 99.6% and 99.4%, respectively, wore masks. Among respondents who returned to work, 75.5% wore a mask at the workplace, while 86.3% of those who have not returned to work will choose to use masks when they return to the workplace. The Chinese public is highly likely to use a mask during COVID-19 epidemic, and the mask usage changed greatly since the COVID-19 outbreak. Therefore, public education has played an important role during the COVID-19 epidemic.

The structural composition of components contributes to the superiority of the geoherb Alisma orientale for "diuresis and diffusing dampness".

The purpose of this study is to explore the intrinsic reasons for the superiority of the salt-made geoherb Alisma orientale via comparing the content of various components of the salt-made geoherb Alisma orientale. The effects of "diuresis and diffusing dampness" using salt-made Alisma orientale from seven different origins were investigated through pharmacodynamic experiments in vivo and in vitro. The results indicated that salt-made Alisma orientale from different origins had diuretic efficacy; this was demonstrated by the significant increase in the volume of rat urine, the concentration of Na+, K+, and Cl- in the urine, and the significant decrease in the levels of AQP-2 in rat renal medulla and HK-2 cells. It was also revealed that the diuretic effect of salt-made Alisma orientale from Fujian Province is stronger than those from other provinces. Moreover, the main components and their proportions in the salt-made Alisma orientale samples were further analyzed via principal component analysis. The results showed that alisol A 24-acetate, alisol B, and 23-acetyl alisol B are the main components of salt-made Alisma orientale, and the optimal structural ratio of alisol A 24-acetate, alisol B, and 23-acetyl alisol B was found to be 5.38 : 14.34 : 11.31 via optimizing the ratios of the three main components. It is worth noting that the optimal ratio of the three main components after optimization is the closest to the ratio of the three main components in salt-made Alisma orientale from Fujian Province. This paper reveals the "mystery" of the content ratio of the main active components and its effect on the efficacy, and showed that the proportional relationship between the content of multiple components is the key to their interactions. Therefore, this method of evaluating the quality of salt-made Alisma orientale is obviously reliable, and this study lays the foundations for quality evaluation of salt-made Alisma orientale and other herb slices.

[Responses of soil extracellular enzyme activities to the anthropogenic transition from desert grassland to shrubland in eastern Ningxia, China]. / å®å¤ä¸œéƒ¨è’æ¼ è‰åŽŸå‘çŒä¸›åœ°äººä¸ºè½¬å˜è¿‡ç¨‹ä¸­åœŸå£¤èƒžå¤–é ¶æ´»æ€§å“åº”.

To understand the responses of soil extracellular enzyme activities to the desert grassland-shrubland anthropogenic transition, we examined soil properties and six extracellular enzyme activities, in soil under vegetation patches and bare interspaces in desert grassland, grassland edge, shrubland edge, shrubland in a typical anthropogenic desert grassland-shrubland mosaic in desert steppe of eastern Ningxia, China. The six measured enzymes included cellobiohydrolase, ß-1,4-xylosidase, ß-1,4-glucosidase, ß-1,4-N-acetylglucosaminidase, leucine aminopeptidase and alkaline phosphatase. We found that soil moisture, soil organic carbon, total nitrogen, total phosphorus, microbial biomass carbon and microbial biomass nitrogen decreased significantly by 26.0%-88.5% with the process of the desert grassland-shrubland anthropogenic transition. All soil properties, except soil organic carbon and soil moisture in grassland edge site, were 3.9%-82.3% higher under vegetation patches than those in bare interspaces in each site. The six extracellular enzyme activities also decreased by 22.1%-82.4% in the transition process, especially for leucine aminopeptidase and alkaline phosphatase, showing significant decrease by 82.4% and 75.5%, respectively. All extracellular enzyme activities but ß-1,4-N-acetylglucosaminidase in shrubland were significantly higher by 10.7%-42.7% under vegetation patches than those in bare interspaces in each site. The activities of six extracellular enzymes were all positively correlated with each other. All of them were positively correlated with soil properties. Moreover, activities of these soil extracellular enzymes responded more positively to the changes of microbial biomass carbon, microbial biomass nitrogen, and total nitrogen in the process of anthropogenic transition.

Carthamus tinctorius L. Extract ameliorates cerebral ischemia-reperfusion injury in rats by regulating matrix metalloproteinases and apoptosis.

We investigate the protective effect of Carthamus tinctorius L. (CTL, also known as Honghua in China or Safflower) on cerebral ischemia-reperfusion and explored the possible mechanisms on regulating apoptosis and matrix metalloproteinases (MMPs). High-performance liquid chromatography method with diode array detection analysis was established to analyze the components of CTL. Middle cerebral artery occlusion rats model was established to evaluate Neurological Function Score and hematoxylin-eosin staining, as well as triphenyltetrazolium was used to examine the infarction area ratio. Transferase-mediated dUTP nick-end labeling was performed for the apoptosis. Apoptosis-related factors, including B-cell lymphoma-2 (Bcl-2), Bax and Caspase3, and MMPs-related MMP2, MMP9, tissue inhibitor of metalloproteinases 1 (TIMP1) in ischemic brain, were assayed by Western blot, reverse transcription polymerase chain reaction, and immunohistochemistry. The data showed that CTL (2, 4 g crude drug/kg/d) treatment could significantly reduce the ischemic damage in brain tissue and improve a significant neurological function score. In addition, CTL could also attenuate apoptosis degree of brain tissues and regulate Bcl-2, Bax, and Caspase 3 and also have a significant decrease on MMP-9 expression, followed by a significant increase of TIMP1 protein expression. These findings indicated that regulation of CTL on apoptosis and MMPs contributed to its protective effect on ischemia/reperfusion injury.

[Changes of endogenous ouabain in rat serum and certain tissues after exposure to simulated weightlessness].

OBJECTIVE: To investigate the changes of endogenous ouabain (EO) in rat serum and some tissues after exposure to simulated weightlessness and to investigate its possible pathophysiology. METHOD: Male Wistar rats were randomly divided into control group (Con) and 1 week tail-suspension group (TS). Enzyme-linked immunosorbent assay (ELISA) was used to detect the content of EO in serum, hypothalamus, pituitary, adrenal gland, kidney, heart and liver. RESULT: Compared with Con, EO increased significantly in serum, hypothalamus, adrenal gland and kidney after tail suspension (P<0.05). CONCLUSION: Simulated weightlessness induced changes of EO in serum and some tissues, which may have some effects on the regulation of hydro-electrolyte metabolism and cardiovascular functions.