The formation of Staphylococcus epidermidis biofilm on the surface of medical biomaterials may resist the antibiotics treatment and cause chronic infection,which has become a research focus in recent years.Multiple genes constitute complex regulatory network which affect the biofilm formation,and play different roles in the different stages of biofilm formation.Accessory gene regulator (agr) is one of the most important genes in the process of biofilm formation.The process of bacterial biofilm formation,research status of regulation mechanism of agr system and its related genes in the formation of biofilm are reviewed,to provide reference of using agr as a target for the treatment of staphylococcus epidermidis biofilm related infections.

Lycopene—a kind of important active compound of caroteinoids, is greatly beneficial to human health with its diverse biological functions. With the elucidation of lycopene biosynthetic pathway and cloning genes of relative enzymes from microorganisms, it is possible to regulate lycopene biosynthesis via genetic engineering. The biosynthesis pathways of lycopene and gene cloning of lycopene biosynthetic enzymes in microorganisms were reviewed, and gene engineering strains documented in previous works including: E.coli and yeast constructed by genetic recombination, mold strains enhanced the ability of producing lycopene by gene manipulation were summarized. At last, compared with the present methods, the problems existed in the process of construction were pointed out.

Aim To study the effects of preconditioning with desflurane, sevoflurane and isoflurane on adenosine triphosphate (ATP) in anoxia-reoxygenation myocardial cells. Methods Rat ventricular myocytes, cultured for 4～5 days, were randomly allocated to five groups: Control group, anoxia-reoxygenation group and groups preconditioned with 1.5 MAC desflurane, sevoflurane or isoflurane following anoxia-reoxygenation. The content of intracellular ATP ,the activities of lactic dehydrogenase(LDH) and creatine kinase(CK), and the cell viability were measured at the end of experiment.Results Preconditioning with 1.5 MAC desfllurane, sevoflurane or isoflurane significantly attenuated the great reduction in ATP and cell viability and the increase of LDH and CK caused by anoxia-reoxygenation. There was a positive correlationship between ATP and cell viability,and a negatiue correlationship between LDH and CK (r was 0.83, -0.87 and -0.82 respectively, P

0.05)indicating no significant loss of correction.The length of the growth of instrumented spine was 13.3 mm.No sever complications in the series. Conclusion The PRSS which dispenses without bony fusion is a safe and an effective instrumen for management of juvenile scoliosis.It provides and maintains desirable scoliosis correction in one stage procedure,while allowing spinal growth.

T polymorphism of TGF-?1 gene related with the degree of L_(4?5) and L_5S_1 disc degeneration.

Objective To investigate air bacteria pollution and the rule of microbes spread in some markets in Guangzhou, aiming at prevention and forecast airborne pathogenic microbes. Bacteria and Staphylococcus aureus were collected to provide reference on evaluation and of the spread of through the air in public. Methods Gravity exposure of microbial media plates was used to sample the airborne bacteria in eight different markets in Guangzhou on a given day, from 2003 to 2005. The simulated experiment in the laboratory was conducted based on the results of natural sampling stations. Results Samples taken at different times showed wide variations with quantities of airborne bacteria (total count) and Staphylococcus aureus ranged from 95 to 1.5?104 cfu per petri dish and from 2 to 1.2?104 cfu per petri dish respectively. Movement of airborne bacteria in the market obeyed quadratic equation pattern. The spread distance of airborne bacteria was among 24 to 26 meters. Maximum airborne bacteria were detected from 17:00 o'clock to 19:00 o'clock in a day. Conclusion The count of market airborne bacteria is markedly more than the limits stipulated in the related national standard GB 9670-1996. Live fowls sold in the markets are the main carriers of bacteria and the potential pollution resource of pathogenic bacteria.

Objective To investigate the pathological features of rabbit' retina at the early stage of sunlight-induced injury.Methods Twenty New Zealand rabbits without any eye diseases were randomly allocated to 4 groups(5 each): animals in group A were fed under normal illumination environment,the animals in group B were fed under normal illumination environment and exposed to constant simulated sunlight,the animals in group C were fed under low illumination environment,and the animals in group D were fed under low illumination environment and exposed to constant simulated sunlight.The pathological changes in rabbits' retina were observed with light and transmission electron microscope.Results The structure of retina in group A and group C were histologically well-defined,uniform in staining,and with regular cell shape.In the animals in group B,vesiculation occurred in the ganglion cell layer,inner nuclear layer and outer nuclear layer,and some of the mitochondria showed swelling.The intramembranous structure of external segments became disorganized.In the animals in group D,vesiculation and swelling occurred in the ganglion cell layer and inner nuclear layer,with disruption of the cell membrane.Vesiculation and swelling were also found in the outer nuclear layer,with reduction in cell quantity.The structure was disorganized,with disorganized cell membrane,obvious swelling of mitochondria,disorganized intramembranous structure of external segments,and loss and vesiculation of the laminal structure.Conclusion The rabbit' retina will be injured when it is exposed to 30 000 lux constant simulated sunlight for 30 minutes.Rabbits fed in a low illumination environment and exposed to constant simulated sunlight may suffer severer injury than those fed in a normal environment and exposed to constant simulated sunlight.

Objective: To observe the relationship between homocysteine(Hcy)and spatial cognitive ability and to evaluate whether vitamin B12 supplementation could protect spatial cognitive ability in rats. Methods: The rats were randomized into three groups. The experimental group was given methionine subcutaneously. The intervention group was given methionine and vitamin B12 subcutaneously. The control group received isometric normal saline. After being raised for 8 weeks, all rats were examined for plasma Hcy and serum vitamin B12 and scores of Y-maze test. The brain tissues of hippocampus were checked immunohistochemically for acetylcholinesterase (AChE). Results: The experimental group developed hyperhomocysteinemia and descreased spatial cognitive ability significantly (P0.05). Conclusion: Homocysteine can impair the spatial cognitive ability in rats and vitamin B12 is effective in lowering Hcy level and protect the spatial cognitive ability of rats.

ObjectiveTo investigate the clinical features of acute myocardial infarction in CAPD patients.MethodsCompare the clinical and laboratory data of 39 patients with CAPD and AMI for the first time (PD group),including clinical symptoms,signs,electrocardiogram changes,myocardial enzyme changes and in hospital mortality,with those of 50 patients without renal insufficient but with AMI for the first time (C group).Diagnosis of AMI was made in hospital.ResultsCompared to C group, the symptoms presented at first in PD group were more atypical and the patients went to see doctor more lately after AMI.Atypical electrocardiogram changes were more in PD group than in C group (61.5% vs 26.0%,P

Objective Geriatric medicine has become an important medical subspecialty,and will have broad prospects for development.By reviewing the brief history of geriatric medicine,it displays its emergence,birth,concept and scope under different background of social civilization and culture between western and eastern countries.Moreover,it presents the development courses of geriatric medicine in terms of clinical medicine,nursing,education,disciplinary development,academic organization,management and innovation among different countries.As the world's population ages,geriatric medicine is facing both great challenges and opportunities.Only by learning the knowledge and experience from the history and renewing ideas,healthcare professionals can promote the comprehensive development of geriatric medicine,which will be full of vigor and vitality.