Objective: To explore influence of ginsenoside Rg1 on coronary artery angiogenesis in rats with acute myocardial infarction (AMI) and its mechanism.Methods: A total of 120 Wistar rats were randomly and equally divided into sham operation group (only received thoracotomy to expose heart without coronary ligation),AMI group (no treatment after model development with ligating left coronary artery) and ginsenoside group (received ginsenoside Rg1 injection on 3h after AMI model development).Infarct area, expressions of vascular endothelial growth factor (VEGF) and its receptor (Flk-1), and VIII factor expression were respectively measured on 24h, one week and five weeks after model development.Results: Compared with sham operation group after five weeks, there were significant rise in myocardial infarction area, number of new blood capillaries and expression levels of VEGF and its receptor Flk-1 in ginsenoside group and AMI group, P<0.05 or <0.01;compared with AMI group, there was significant reduction in myocardial infarction area [(51.31±9.67)% vs.(29.33±6.70)%], and significant rise in number of new blood capillaries [(18.31±5.07) vs.(46.79±13.67)], expressions of VEGF [greyscale value: (84.3±8.7) vs.(32.9±16.7), greyscale value was inversely proportional to expression] and Flk-1 [(17.6±8.7) vs.(59.9±16.2)] in ginsenoside group, P<0.05 or <0.01.Conclusion: Application of ginsenoside Rg1 in AMI rat model can mobilize marrow stem cells gather in ischemic myocardium, upregulate expressions of VEGF and its receptor Flk-1, effectively promote angiogenesis of blood capillaries, and reduce myocardial infarction area.

LA G1 was identified as a gene that is differentially expressed during the yeast replicative life span and was shown to play a role in determining yeast longevity. The cDNA of rat LASS1, the mammalian homolog of yeast LA G1, was cloned from rat cerebral cortex and sequenced, which is different to the predicted sequence in the GenBank. Sequence analysis revealed that this cDNA clone contains an open reading frame of 1 053 bp. The deduced amino acid sequence has 350 residues and shares a predicted Laglp motif and a TLC domain conserved in Lag1 proteins. Total RNAs were isolated from rat cerebral cortices at varying ages: newborn, one month, six months, twelve months, and twenty-four months. Semi-quantitative RT-PCR and Northern blot analysis were performed to analyze the LASS1 expression level in rat cerebral cortex tissues at varying ages. Senescence-associated β-galactosidase (SA-β-gal) activity was firstly used as a biomarker for assessing senescence in rat neurons. The results showed that LASS1 expression was upregulated from newborn to adult rats (1～6 month) and declined in aged cortex. SA-β-gal staining positive neurons significantly increased in the aged cerebral cortex. The age-related expression alternation of LASS1 in rat cerebral cortex provides an important clue in exploring the role of LASS1 in mammalian neuron aging.

Objective To screen cell growth and senescence-related genes of the parasitic pmtist Trichomonas vaginalis,we launched an EST program and isolated two cDNA clones from a T.vaginalis cDNA library,which showed high homology in deduced amino acid sequences to yeast Sir2 and designated as TvSir2 and TvSir2-like.Method The cDNA sequence of TvSIR2 had a length of 1034 base pairs (bp) with an open reading frame of 915 bp,and TvSIR2-like,1214 bp with an open reading frame of 1116 bp.Result The two deduced amino acid sequences shared all the three conserved cole domains with yeast Sir2 and its homologues,suggesting that the two clones were Sir2 homologues. A cDNA fragment from each cDNA clone was subvloned into the expression vector pET-41a.The expression of the fusion proteins in E.coli BL21 stains was induced by isopropylthio-β-D-galactoside (IPTG).Two anti-sera were prepared by immunizing two guinea pigs with the purified fusion proteins, Western-blot analysis demonstrated that each anti-serum reacted with the corresponding recombinant protein and detected a clear band (TvSir2,34 000 Mr;TvSir2-like,42 000 Mr)in protein extracts of the protist.Immunofluolescence techniques showed that TvSir2 and TvSir2-like proteins were both localized in the legions of perinuelear (ER) and Golgi complex.Conclusion Our data suggest that TvSir2 and TvSir2-like were two members of Sir2 family.Their biological functions in the protist would be further studied.

Modeling biosecurity events based on mathematical theories to reveal the inherent mechanism can shed light on the development of biosecurity events and offer accurate scientific support to emergency preparation and response , con-tributing much to national biodefense capability .This paper reviews the applications of mathematical theories as a research and analytic tool in biosecurity and discusses the trends of development in this field .

To explore the transmission patterns and advise public health departments , this paper establishes a dynamic model on the peculiarity of avian influenza A (H7N9) virus and analyzes the dynamic feature of this type of bird flu trans-mission between humans and birds .Results show that this type of bird flu can be controled , and that closing down live-bird markets is the most effective method .

Human behavior significantly affects the spreading dynamics of infectious diseases in large populations .The study of the interplay between the adaptive behavior and the epidemic dynamics underlies the professional information release and psychological counseling mechanism and is conducive to disease control and social panic elimination .This paper aims at the investigation of the effect of adaptive behaviors on the spreading dynamics of epidemics in structured populations .We analyzed the empirical data on adaptive behavior from several large epidemics after the outbreak of SARS in 2003 and confirmed the induction effect of two main information sources on adaptive behavior , e.g., public available information and local perceived information .Then we investigated the effect of adaptive behavior on epidemic dynamics in a structured population based on two primary models , e.g., health-belief model and network model .The results showed that the individual adaptive behavior had significantly decreased the chance of infection and thus mitigated the epidemics . Human adaptive behavior has a significant effect on spreading dynamics of epidemics .An effective information release mechanism will induce human adaptive behavior and is thus conducive to control of epidemics .

Emerging large-scale epidemics not only cause heavy casualties , but have a huge impact on economy .This paper analyzes the characteristics and manners of the economic impact of emerging large -scale epidemics .Economic losses and the national economic impact of emerging large-scale epidemics are analyzed at three levels: microscopic , supply and demand , and macroscopic .Then the relationship between the these levels is discussed .This research is expected to play an important role in the construction of an appropriate economic model for analysis and calculation of economic losses of emerging large-scale epidemics , and in the formulation of the best cost-effective ratio for preventin and control measures against emerging large-scale epidemics .

Objective To assess efficacy and safety of enhanced rehabilitation program for patients with colorectal cancer surgery. Methods One hundred and ten consecutive patients admitted to general surgery department at Beijing Chaoyang Hospital during October 2007 to October 2009 undergone with fasttrack colorectal cancer surgery and enhanced rehabilitation were prospectively studied, with 117 patients undergone with same colorectal cancer surgery by traditional perioperative treatment during May 2005 to September 2007 as controls. Restoration of their gastrointestinal function, occurrence of complications, fatality and length of hospital stay after surgical operation were observed in the group of enhanced rehabilitation and control group. Results Demographic characteristics, stage classification of illness and surgical operation methods were comparable in both groups. The first day with air discharge from the flux was earlier in enhanced rehabilitation group than that in controls (2. 5 vs. 3. 5 day after surgery, P ＜ 0. 05 ), and the former could tolerate solid food earlier than the latter (6.0 vs. 6.7 days after surgery, P=0.028). Overall morbidity of complications was less in the group with enhanced rehabilitation than that in controls (23.6% vs. 39. 3%,P =0. 011 ) and shorter length of hospital stay was observed in the former than that in the latter (9. 0 vs. 10. 8 days after surgery, P =0. 041 ). There was no difference in mortality, incidence of anastomotic leakage, and infectious and non-infectious complications between the two groups. Conclusions Enhanced rehabilitation program is safe and effective following colorectal cancer surgery to accelerate restoration of gastrointestinal function, reduce complications and shorten hospital stay after colorectal cancer surgery.

Computational epidemiology is a fast-developing and interdisciplinary research area .Through comprehensive computation-analysis of multi-uncertain factors affecting the epidemic process , this method may add to our knowledge about epidemic patterns and help design reasonable response plans and emergency strategies .This article briefly summarizes the idea and theory of computational epidemiology based on related researches in the recent years , introduces the application of this method in case of smallpox bioterrorism and influenza pandemic , and predicts the development of this area .

Benign distal biliary strictures (BDBS) are fibrous tissue proliferation and biliary stricture caused by long-term stimulation of the affected bile ducts due to non-neoplastic factors such as iatrogenic injury, chronic inflammation, and bile duct stones, which further leads to recurrent cholangitis, obstructive jaundice, and liver impairment. Relieving distal biliary obstruction and maintaining bile duct patency for a long time are the core of the treatment of BDBS. With the continuous innovation of endoscopic retrograde cholangiopancreatography techniques, new techniques such as endoscopic stenosis dilatation, stent implantation, and magnetic compression anastomosis are gradually becoming effective treatment methods for BDBS. This article elaborates on the advances in endoscopic therapy for BDBS, so as to provide a reference for clinical research.