Background Choroidal neovascularization(CNV)has been descrihed as a main reason of visual loss in a lot of ocular diseases.Researches showed that local hypoxia and retinal pigment epithelial(RPE) cells play an important role in the formation of CNV.A closely relationship of angiopoietin-2 (Ang-2) and angiogenesis has been proved.However,whether the expression of Aog-2 in hypoxic cultured human RPE cells is associated with the pathogenesis of CNV is still below understood.Objective This study was to investigate the effects of hypoxia on expression of Ang-2 in cultured human RPE cells in vitro,and discuss the possible effects of Ang-2 in the formation of CNV.Methods Human RPE cells were cultured and passaged,and 4-7 generation of cells were used in the experiment.The cells were incubated in cultural plate at the density of 5×107 cells/L.The culture medium containing 200 μmol/L CoCl2 was used to establish the hypoxia model of human RPE cells culturecd in vitro for 0.5,1,2,4,6,12and 24 hours,and the RPE cells cultured under normoxia were as controls.Reverse transcription polymerase chain reaction(RT-PCR) was used to detect the expression of Ang-2 mRNA in cultured human RPE cells,and enzymelinked immunosorbnent assay(ELISA) was used to assay the content of Ang-2 protein in supernatant of cultured human RPE cells.Results The survival rate of human RPE cells was 90％ after resoscitation.The fourth generation of cells showed the fusiform with the less pigment in them.The Ang-2 mRNA/β-actin mRNA value in human RPE cells was significantly different among various groups(F=1086.30,P=0.00),The Ang-2 mRN A/β-actin mRNA value in hypoxia cultured for 0.5 hours group began to increase and peaked in hypoxia culture for 4-6 hours group,with the significant differences in comparison with normoxia control group(P＜0.05).The Ang-2 mRNA/β-actin mRNA value decreased to the baseline level at hypoxia for 24 hours.The ELISA analysis showed that the concentration of Ang-2 protein in supernatant of RPE cells showed significant difference among groups(F=1034.00,P=0.00).The concentration of Ang-2 protein increased at hypoxia culture for 0.5 hours and peaked at 6 hours,showing significant differences in comparison with the control group (P＜0.05).Conclusions Hypoxia could significantly up-regulate the expression of Ang-2 in human RPE cells cultured in vitro.Ang-2 expresses highly in the early stage of hypoxia,implying that Ang-2 participates in the formation of CNV.

Objective To explore the feasibility of language sample analysis in assessment of language development in children in order to provide evidences for its clinical application. Methods The study population consisted of a cross-sectional sample of 50 preschool Putonghua-speaking children aged 4 to 6 years. The data on measurement of utterance length (MLU) and lexical diversity (D) were computed from 20 minutes' conversational language samples, and correlation analysis was conducted among MLU, D, age, Wechsler Preschool and Primary Scale of Intelligence (WPPSI) and Peabody Picture Vocabulary Test (PPVT). Splited sample analysis by comparing MLU of first one hundred utterances and MLU of last one hundred utterance, D of odd lexicals and D of even lexicals were conducted to test the validity of language sample indictors. Results MLU and D development of the preschool Putonghua-speaking children were positively related to age. MLU, D, age, verbal intelligence quotient (VIQ) and PPVT were associated with each other (P<0.05 or P≤0.01) except age and VIQ(P>0.05). There were significant correlations between MLU of first one hundred utterances and MLU of last one hundred utterances and between D of odd lexicals and D of even lexicals(P=0.000). Conelusion Language sample analysis proves to be feasible in assessment of language development in preschool children aged 4 to 6 years.

Adolescent ; Antigens, CD34 ; metabolism ; Bone Neoplasms ; diagnostic imaging ; metabolism ; pathology ; Chondrosarcoma, Mesenchymal ; metabolism ; pathology ; Diagnosis, Differential ; Hemangiopericytoma ; diagnostic imaging ; metabolism ; pathology ; Humans ; Male ; Platelet Endothelial Cell Adhesion Molecule-1 ; metabolism ; Sarcoma, Synovial ; metabolism ; pathology ; Tomography, X-Ray Computed ; Vimentin ; metabolism

Humans ; Periodontal Diseases ; therapy ; Tissue Engineering

Adult ; Endocarditis, Bacterial ; complications ; diagnosis ; Humans ; Male ; Myocardial Infarction ; diagnosis ; etiology

The cerebral blood flow of infant is effected by physiological and pathological factors.As the cerebrovascular autoregulation of neonates is poor,in pathological cases,especially when hypoxemia and hypercapnia impaired regulation of its own,lead to changes in cerebral blood flow,then resulting in severe brain injury.It has made enormous progress in the research on the changes of cerebral blood flow in newborns in recent years.In normal infants,cerebral blood flow velocities is positively correlated to gestational age and body weight,and increase gradually with day-age in the first week after birth.The cerebral blood flow of newborn with brain injury can present as insufficiency,over-perfusion or low speed high-resistance earlier and high speed low-resistance later.Different results may be related to the duration and severity of asphyxia,but all of those are signs of damage of self-regulatory function of cerebral blood flow.Cerebral hemodynamic change is the important pathogenesis mechanism of brain injury.

Objective To investigate the effects of intense pulsed light(IPL) on the collagen metabolism in human fibroblasts.Methods The callan foreskin fibroblasts were cultured and treated with different wave length and designed dose of IPL irradiation(590-1 200 nm,and 29 J/cm2),while 10 without IPL irradiation as controls.By culturing 1,12,24 and 48 h after the irradiation,the synthesis of collagen was measured by 3H-proline incorporation determination. Results The synthesis of collagen activity increased significantly(P

0.05),but the 3-year recurrent rates were significantly different(P

0.05).Conclusion High level of Blys could be observed in serum of patients with SLE and somewhat correlated with the lupus acitivity,although the level of Blys in serum can not reflect morbility and mortality of SLE patients.

The high-copy-number plasmid pcDNA3.1+ is unstable within S almonella typhimurium. A novel plasmid pmcDNA3.1+ was constructed by removin g the promoter sequence of ampicillin resistance gene (bla gene) in plasmid pcDNA3.1+. In contrast to pcDNA3.1+, pmcDNA3.1+ was stable within Salmonel la typhimurium SL7207 in LB medium with or without ampicillin. Further experi ments showed the ?-lactamase activity of Salmonella typhimurium SL7207(pmc DNA3.1+) was apparently lowered than that of Salmonella typhimurium SL7207( pcDNA3.1+) and the high ampicillin concentration was maintained longer in LB me dium culturing Salmonella typhimurium SL7207(pmcDNA3.1+). When mice were a dministered with Salmonella typhimurium SL7207(pmcDNA3.1+) intraperitoneall y, more than 95% of Salmonella cells separated from the spleen still harbore d the plasmid pmcDNA3.1+ 7 days later; but 99% of Salmonella cells lost the plasmid pcDNA3.1+ at day 3 in mice innoculated with Salmonella typhimurium SL7207(pcDNA3.1+). By lowering the expression of bla gene, the rapid deco mposition of ampicillin in LB medium was avoided and the metabolic pressure was relieved for the host cells. This method offers a solution for the problem of t he instability of high-copy-number plasmid within Salmonella typhimurium.