Virtual experiment is the application of virtual reality technology in experiment sciences.In the physiology teaching, virtual reality modules are made up of experiment theory module,experiment process module,virtual reality module,review mod- ule and experiment report module.We set up a virtual physiology experiment system by author ware and other software.

OBJECTIVETo investigate the potential role of caveolin-1 (CAV-1) on membrane estrogen receptor (mER) mediated proliferation of endothelial progenitor cells (EPCs).

METHODSBone marrow (BM)-derived EPCs were cultured. The proliferation of EPCs induced by estradiol (E₂)-BSA in the absence or presence of ICI 182, 780 (a pure ER inhibitor), MβCD and CAV-1 siRNA was determined by [³H]-thymidine incorporation. The expression of CAV-1 was detected by Western blot.

RESULTSProliferation of EPC peaked after 10(-8) mol/L E₂-BSA culture for 24 h (87.5% increase vs. control), and this effect could be inhibited by estrogen receptor blocker ICI 182, 780, indicating that mER-initiated membrane signaling pathways was involved in the proliferation effect of estrogen on EPC. Both cholesterol depletion and CAV-1 siRNA significantly attenuated E₂-BSA induced [³H]-thymidine incorporation. Western blot result confirmed that cholesterol depletion or CAV-1 siRNA significantly decreased CAV-1 protein expression (-18.6% or -41.2% vs. 10(-8) mol/L E₂-BSA alone).

CONCLUSIONOur results suggested that estradiol promoted EPC proliferation through activating CAV-1 pathway.

Animals ; Caveolin 1 ; immunology ; pharmacology ; Cell Proliferation ; drug effects ; Cells, Cultured ; Endothelial Cells ; cytology ; metabolism ; Endothelium, Vascular ; cytology ; metabolism ; Estradiol ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptors, Estrogen ; metabolism ; Stem Cells ; cytology ; metabolism

Rat vascular smooth muscle cells (VSMC) were used to study the effect of 17beta -estradiol (E(2)) on cellular proliferation (cell counting), DNA synthesis ((3)H thymidine incorporation), MTT, c -fos mRNA expression and nitric oxide (NO) release. The results obtained showed that E(2) (10(-12) 10(-8) mol/L) induced NO release from VSMC in a concentration-dependent manner; 10(-8) mol/L E (2)significantly inhibited VSMC cellular proliferation and DNA synthesis induced by 10% FCS and 10(-7) mol/L ET-1, which was obviously reversed by 10(-7)mol/L tamoxifen and 10(-6) mol/L L-NAME; after a pretreatment for 24 hours, 10(-8)mol/L E(2) significantly inhibited VSMC c -fos mRNA expression induced by 10(-7)mol/L ET-1, which was also obviously reversed by 10(-6) mol/L L-NAME. These results suggest that the inhibitory effects of E(2) on VSMC cellular proliferation and c -fos mRNA expression are closely related with NO release in VSMC, which is, at least, partly medicated by ER.
Animals ; Cell Division ; drug effects ; Cells, Cultured ; Estradiol ; pharmacology ; Female ; Muscle, Smooth, Vascular ; cytology ; metabolism ; Nitric Oxide ; metabolism ; physiology ; Proto-Oncogene Proteins c-fos ; biosynthesis ; RNA, Messenger ; biosynthesis ; Rats ; Rats, Sprague-Dawley

The aim of the present study was to investigate the role of caveolin-1 in the inhibition of endothelin-1 induced proliferation of vascular smooth muscle cells (VSMCs) by 17beta-estradiol. In the cultured rat thoracic aortic VSMCs, proliferation of VSMCs was determined by using [(3)H]-thymidine incorporation and the expression of caveolin-1 protein was measured by immunofluorescence assays and Western blotting. The measurement demonstate VSMCs exposed to various concentrations of endothelin-1 (1-100 nmol/L) for 24 h induced an increase in [(3)H]-thymidine incorporation. Pretreament with various concentrations of 17beta-estradiol (0.1-10 nmol/L) for 24 h inhibited the proliferation effect of endothelin-1. Immunofluorescence assays showed that after 24 h treatment of VSMCs with endothelin-1 (100 nmol/L), the expression of caveolin-1 in VSMCs was significantly increased, whereas pretreament with 17beta-estradiol (10 nmol/L) for 24 h inhibited the effect. Western blotting results further proved that endothelin-1 inhibited and 17beta-estradiol increased the expression of caveolin-1 in VSMCs. These results demonstrate that 17beta-estradiol inhibits the VSMCs proliferation induced by endothelin-1, and that the effect of estradiol is probably mediated by caveolin-1.
Animals ; Aorta, Thoracic ; cytology ; Caveolin 1 ; physiology ; Cell Division ; Cells, Cultured ; Endothelin-1 ; antagonists & inhibitors ; physiology ; Estradiol ; pharmacology ; Muscle, Smooth, Vascular ; cytology ; Rats ; Rats, Sprague-Dawley

In the present study, confluent bovine aortic endothelial cells (BAECs) were used to study the rapid nongenomic effects of 17beta-estradiol and the membrane impermeable conjugated 17beta-estradiol (E(2)BSA) on the activation of endothelial nitric oxide synthase (eNOS) and mitogen activated protein kinase (MAPK). eNOS activation was assessed in whole cells by measuring [(3)H]L-arginine conversion to [(3)H]L-citrulline. MAPK activity was determined by Western blotting. The results obtained show that the addition of various concentrations of E(2) (0.001-1 micromol/L) resulted in 122+/-29, 186+/-17, 83+/-20 and 157+/-29% increases in eNOS activity, respectively, in BAECs within 15 min of exposure to the hormone. E(2) (0.01 mol/L)-stimulated eNOS activity was detectable during 5-, 15- and 30- min incubation which yielded increases of 37+/-6, 56+/-9 and 38+/-8%, respectively. The increase reached a plateau from 15 through 30 min and rapidly declined thereafter. E(2)BSA 17.5 ng/ml also enhanced eNOS activity by an increase of 35+/-9% above the basal activity. The effect of E(2) and E(2)BSA on eNOS activation was unaffected by actinomycin D 25 microg/ml but was obviously inhibited by tamoxifen (0.1 micromol/L) and PD98059 (50 micromol/L). Compared with control E(2) and E(2)BSA stimulation of BAECs for 15 min caused an increase in MAPK activity by 428+/-17 and 360+/-14% respectively. This effect was blocked by tamoxifen. These results suggest that there might be the membrane estrogen receptor localized on BAECs, which mediates the rapid nongenomic effect of estrogen on eNOS activation through MAPK pathways.
Animals ; Aorta ; cytology ; Cattle ; Cell Membrane ; metabolism ; Cells, Cultured ; Endothelial Cells ; cytology ; metabolism ; Estradiol ; pharmacology ; Mitogen-Activated Protein Kinases ; metabolism ; Nitric Oxide Synthase Type III ; metabolism ; Receptors, Estrogen ; physiology

AIMTo investigate the mechanisms of 17beta-estradiol on the production of endothelin-1 in vascular smooth muscle cells.

METHODSAfter incubation VSMC with various concentrations of 17beta-estradiol (10(-9) - 10(-7) mol/L) or plus L-NAME(10(- 6) mol/L) for different times, the concentration of endothelin-1 was measured. At the same time, the activity of endothelin converting enzyme-1 was analyzed, and the expression of preproET-1mRNA was measured by RT-PCR.

RESULTSIn basal conditions, 17beta-estradiol could inhibit the production of endothelin-1 in VSMC, and the action of 17beta-estradiol had nothing to do with the activity of endothelin converting enzyme-1. L-NAME inhibited the effect of 17-estradiol on the production of endothelin-1 in VSMC. RT-PCR results showed that 17-estradiol inhibited the preproET-1 mRNA expression, and whereas L-NAME reversed this action of 17beta-estradiol.

CONCLUSIONIn basal conditions, 17beta-estradiol decreases the preproET-1 mRNA expression through NO-pathway to inhibit the production of endothelin-1 in cultured VSMC.

Animals ; Cells, Cultured ; Endothelin-1 ; biosynthesis ; Estradiol ; pharmacology ; Muscle, Smooth, Vascular ; cytology ; drug effects ; metabolism ; Myocytes, Smooth Muscle ; drug effects ; metabolism ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; drug effects

Clinical epidemiologic data and animal experimental studies regard estrogen as being protective against the development of cardiovascular diseases. The mechanisms by which estrogen affects the development of vascular diseases are not clear. Recent studies demonstrated that the cardiovascular protective effects of estrogen are closely related to nitric oxide (NO) pathway. Our previous study proved that estrogen inhibited the proliferation and oncogene expression of vascular smooth muscle cells (VSMCs) induced by endothlin 1 (ET-1) and serum,this effect was mediated by NO release. In the present study, we investigated the role of inducible nitric oxide synthase (iNOS) in the VSMCs cycle arrest induced by 17 beta-estradiol (E(2)). The effects of E(2) on iNOS activity and protein expression in cultured rat VSMCs and the influence of NOS inhibitor N(G)-nitro-L-arginine methylester (L-NAME) on the inhibitory effect of E(2) on cell cycle were investigated. NOS assay kit was used to measure the activity of iNOS and protein expression of iNOS was determined by Western-blot. Cell cycle analysis was accessed by flow cytometry. The results obtained showed that E(2) increased iNOS activity of VSMCs but not in a dose-dependent manner. E(2) 10 nmol/L increased the iNOS activity of VSMCs distinctly at two time points: 30 min and 12 h. These effects were significantly inhibited by estrogen receptor (ER) antagonist Tamoxifen (0.1 micromol/L) and NOS inhibitor L-NAME (1 micromol/L). E(2) increased iNOS protein expression of VSMCs in a dose-dependent manner. The effect of E(2) on iNOS protein expression of VSMCs started at 3 h, distinctly increased at 12 h and then decreased. Tamoxifen significantly inhibited the E(2)-induced iNOS protein expression of VSMCs. ET-1 increased cell percentage of S phase and G(2)+S/G(1). This effect was inhibited by E(2). L-NAME significantly attenuated the inhibitory effect of E(2) on cell cycle of VSMCs. The results suggest that E(2) induced G(1) arrest of VSMCs, which was associated with an increase in iNOS activity and protein expression of VSMCs. These effects were at least mediated by estrogen receptor partly.
Animals ; Cell Cycle ; drug effects ; Cell Division ; drug effects ; Cells, Cultured ; Endothelin-1 ; metabolism ; Estradiol ; pharmacology ; Estrogen Antagonists ; pharmacology ; Female ; Muscle, Smooth, Vascular ; cytology ; Nitric Oxide Synthase ; metabolism ; physiology ; Nitric Oxide Synthase Type II ; Rats ; Tamoxifen ; pharmacology

OBJECTIVEDespite progress in antibiotic therapy and intensive care, childhood bacterial meningitis (BM) remains a devastating disease. We conducted this study to investigate the changes in clinical characteristics, the etiologic agents and antimicrobial susceptibility of BM during the past 10 years in children under 14 years of age.

METHODSThese 126 patients were divided into two groups according to their date of admission. Group 1 included 64 patients admitted from January 1998 to December 2002, and group 2 included 62 cases admitted from January 2003 to December 2007. All pediatric medical charts of them were reviewed.

RESULTSThe predominant isolated bacteria from CSF were coagulase-negative staphylococcus (17/62, 27.4%) and Escherichia coli (9/62, 14.5%) in group 2. The resistance rate of staphylococcus against oxacillin (MRS) was 68.4% (13/19) in group 2, significantly higher than that of group 1 (16.7%, 2/12). Among 126 cases, 42 had seizure attack and 16 had consciousness disturbance, the proportions of them in group 2 (11/62, 17.7%; 4/62, 6.4%) were lower than those in group 1 (31/64, 48.4%; 12/64, 18.8%, P < 0.05). Cases in group 2 survived with complications [13/62 (21.0%)] and sequelae [11/62 (17.7%)] were lower than those in group 1 (24/64, 37.5%, 23/64, 35.9%, P < 0.05), but the rate of empirical therapy modification in group 2 (21/62, 33.9%) was higher than that in group 1 (7/64, 10.9%, P < 0.01).

CONCLUSIONThe predominant bacteria in children with BM are staphylococcus and Escherichia coli in recent years. The antibiotic resistance rate of bacteria has been higher year after year. The clinical patterns of pediatric BM have changed with a decrease in clinically serious cases, complications and sequelae, but an increase in modification of empirical therapy.

Anti-Bacterial Agents ; pharmacology ; Child ; Child, Preschool ; Cross Infection ; microbiology ; Drug Resistance, Bacterial ; Escherichia coli ; drug effects ; isolation & purification ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Meningitis, Bacterial ; epidemiology ; microbiology ; Retrospective Studies ; Staphylococcus epidermidis ; drug effects ; isolation & purification

The longitudinal study sought to examine the dynamic development of cognitive skills for reading among elementary-level students in Mainland China.Two groups of students in first (n=164,mean age=6.65 years at first test) and second grade (n=202,mean age=7.73 years at first test) were followed on orthographic awareness,morphological awareness and rapid automatized naming (RAN) for two years.The children exhibited significant improvement in orthographic awareness,morphological awareness and RAN from grades 1 to 4.More importantly,to the orthographic and morphological awareness,while the children took a leap from grade 1 to 2 and grade 3 to 4,the progress developed at relatively slow rates from grade 2 to 3.In order to assure children's development of orthographic and morphological awareness,evidence-based orthographically and morphologically enhanced instruction is needed for Chinese children in the early elementary years,especially for those at the stage from grade 2 to 3.

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