Objective To explore the effect of metformin on hepatoma cells senescence and the underlying mechanism.Methods Cell proliferation,cycle and apoptosis were examined by MTS and flow cytometry assay in response to different concentrations of metformin(0,0.01,0.1,1,10 and 50mmol/L).Senescence-associated β-galactosidase (SA-β-ga1) staining and senescence marker Dec1 protein levels were used to evaluate the effect of metformin on hepatoma cells senescence.In addition,protein expression of p-AMPK,p-ACC and AMPK was detected by Western blot analysis.Results Metformin suppressed proliferation of HepG2 cells in a dose-dependent manner.High concentrations of metformin (10 and 50mmol/L) promoted cell apoptosis,while lower doses of metformin (0.01,0.1 and 1mmol/L) led to enlarged and flatten senescent morphology and increased SA-β-ga1 positive cells.Moreover,cell cycle was blocked in G0/G1 phase and protein levels of senescent marker Dec1,p-AMPK and p-ACC were significantly enhanced,whereas AMPK protein expression was almost unchanged.Conclusion We showed here that high dose of metformin promotes HepG2 cells apoptosis,but low doses of metformin induce cellular senescence,which may be related to the activation of AMPK signaling.These data will provide vital evidence for improving the outcome of comprehensive treatment in HCC patients by driving hepatoma cells to undergo senescence.

Objective To explore the effect and molecular mechanism of HDAC inhibitor SNDX-275 inhibiting cell proliferation in ErbB2-overexpressing breast cancer BT474 cells.Methods Breast cancer BT474 cells were treated with HDAC inhibitor SNDX-275,setting as test group,and the cell line treated with phosphate buffered saline (PBS)as control.The concentration of SNDX-275 were 0,0.5,1 .0,2.0,3.0,4.0 μmol/L respectively.Cell proliferation was analyzed by MTS assay and colony formation assay,the expressions of ErbB2, ErbB3,p-Akt were analyzed by Western blotting,and the expressions of miR-125a,miR-125b were analyzed by RT-PCR.After transfecting miRNA125 inhibitor into BT474 cells,the inhibition rate of SNDX-275 was tested by MTS assay .Results MTS result showed that SNDX-275 inhibited cell proliferation in BT474 cells in a dose-dependent manner.The inhibition rate of 4.0 μmol/L SNDX-275 was about (68.00 ±4.45)%.Clone assay indicated SNDX-275 could inhibit the proliferation of BT474 cells.Western blotting result indicated that SNDX-275 significantly inhibited the protein expressions of ErbB2,ErbB3 and p-Akt,RT-PCR result illustrated 2 μmol/L SNDX-275 could increase the expressions of miR-125a and miR-125b about 3.22 ±1 .17,5.42 ±0.38 times compared with the PBS control respectively,the difference has a statistical significance (t =4.338,P =0.049;t =21 .805,P =0.002).MTS result indicated that compared with the PBS control,the inhibition rate of SNDX-275 group was (56.97 ±3.56)%,while the inhibition rate of SNDX-275 and miRNA125 inhibitor group
was (10.67 ±2.21 )%,with a statistical significance(t =-10.993,P =0.008).Conclusion SNDX-275 could inhibit cell proliferation of ErbB2-overexpressing breast cancer BT474 cells,by inhibiting ErbB2-ErbB3-Akt sig-nal pathway through up-regulating miR-125a and miR-125b.

Objective To investigate the relationship of glycoprotein serglycin (SRGN) expression with invasion and metastasis of breast cancer cells,and the role of microRNA in the regulation of SRGN expression.Methods Real-time quantitative polymer ase chain reaction (PCR) and Western blot were used to detect the differences in SRGN expression between higher metastasis Michigan cancer foundation-7 (MCF-7)/5-Fu breast cancer cell lines and weaker metastasis MCF-7 cell line.The siRNA interference experiment and in vitro Transwell experiment were used to detect effect of SRGN on the ability of invasion and metastasis of breast cancer cells.Bioinformatics software was used to predict miRNAs targeting SRGN,and integrated microRNA differentially expressed chip data between breast cancer cell MCF-7 versus MCF-7/5-Fu.The miRNA quantitative PCR was used to determine the differences of candi date miRNA expression.After transfection of microRNA minics,Western blot was used to test candidate microRNA target SRGN.Transwell experiment was used to test the effects of candidate microRNAs on tumor cell invasion and metastasis.Results SRGN was increased significantly in MCF-7/5-Fu cells,and the invasion and metastasis of tumor cells were inhibited when SRGN was interfered.In addition,miR181 b/c expressed in MCF-7/5-Fu cells was reduced significantly,negatively correlated with SRGN expression,and targeted SRGN expression.It inhibited invasion and metastasis of tumor cells.Conclusions MicroRNA181b/c inhibits metastasis of breast cancer by targeting SRGN.

OBJECTIVETo analyze the status and characteristics of dental manpower in the center for disease controls (CDC) in Sichuan Province and to provide more evidence for strengthening the oral healthcare workforce in the CDC system.

METHODSA mass survey on dental manpower was made in CDCs in Sichuan Province through questionnaire investigation. Data were collected and entered with the Epidemiological Dynamic Data Collection (EDDC) platform and analyzed with SPSS 13.0 software.

RESULTSSichuan Province had 0.15 hospitals providing oral health services and 0.38 dentists on average per 10,000 people. About 65.53% (135/206) of the CDCs had one department responsible for the oral health service. However, oral health care personnel comprised only 2.23% (237/10,624) of the personnel of the whole CDC system. About 64.67% (119/184) of county CDCs and 47.62% (10/21) of city CDCs knew well the dental health status of local residents. Less than 5% of the CDCs used the data and assisted in the policy making of public health administrators.

CONCLUSIONThe dental care personal deficit exists in the CDC system in Sichuan Province. The distribution and composition of dental manpower are not reasonable. The oral health service ability of CDCs in Sichuan Province should be strengthened and improved.

Objective To investigate errors and the mechanism of acalculia in patients with left or right hemisphere cerebral infarction.Methods Fifty-six patients with single hemisphere cerebral infarction and 56 normal adults who were matched in age,sex and years of education were tested with EC301-CR.The patients were divided into a left hemisphere cerebral infarction group(n =34)and a right hemisphere cerebral infarction group(n =22).Results The scores on 30 out of 32 EC301-CR items were significantly lower among the patients than in the normal control group.Scores on 14 EC301-CR items were significantly lower in the left hemisphere group than in the right hemisphere group.In the left hemisphere group the item scores of aphasia patients were significantly lower than those of no-aphasia patients except on digit identity.Conclusion Mathematical processing and calculation were impaired in patients with single hemisphere cerebral infarction.Calculation was significantly worse among left hemisphere patients compared with right hemisphere cerebral infarction.There was a highly significant correlation between acalculia and aphasia.

Objective To investigate the molecular mechanism for change in permeability in brain microvascular endothelial cells (bEnd.3) induced by lipopolysaccharide (LPS). Methods Monolayers of bEnd.3 were exposed to LPS,in the presence or absence of exoenzyme C3 transferase. We monitored the monolayer barrier integrity by transendothelial electrical resistance assay (TEER),activity of RhoA by pull down assay,NF-κB by luciferase reporter assay,and F-actin dynamic structure by Rhodamine-phalloidin staining. Results Incubation of monolayers with LPS caused substantial barrier hyperpermeability. Under the had been treated for 3 and 12 h with LPS (P＜0.05). Such effects could be inhibited partly by pretreatment of RhoA inhibitor exoenzyme C3 transferase. LPS activated RhoA and NF-κB at 0.5 h. The C3 transferase could significantly reverse the NF-κB activation (P＜0.05). The F-actin rearrangments displayed in a time-dependent manner and occurred originally after the stimulation of LPS for 3 h,which could be diluted by the pretreatment of C3 transferase as well. Conclusion LPS induces the disruption of F-actin cytoskeleton and brain microvascular endothelial barrier integrity,in part,through RhoA and NF-κB activation. The mechanism underlying this pathophysiological effect of RhoA is to influence the disruption of the F-actin cytoskeleton by regulating NF-κB activites.

To explore the effect of estrogen on pathogenesis of osteoporosis in women with maintenance hemodialysis. One hundred and twenty women aged 18-45 years had been undergoing maintenance hemodialysis for ≥ 3 months were included. Of them ,60 women without osteoporosis served as control group and the other 60 women with osteoporosis as observation group. Serum concentrations of estradiol, tumour necrosis factor-α (TNF-α), parathyroid hormone (PTH), and calcium were determined, meanwhile bone mineral density (BMD)was measured by quantitative computed tomography. Serum estradiol levels in the observation group were lower while TNF-α level were higher than those in control group (all P<0. 05). PTH and calcium levels were not significantly different (P= 0.567 and P = 0. 588). In the observation group, linear correlation analysis revealed positive correlation (r = 0. 865 ,P<0. 01)between estradioi and BMD,while multiple linear regression analysis showed that serum estradiol and calcium levels were positively correlated with BMD, and the concentrations of TNF-α and PTH were negatively correlated with BMD (F= 140.32 ,P<0.01). Estradiol levels were found to have greater effect on BMD(t=5. 386, P<0. 01). Lowered serum concentration of estradiol in women with maintenance hemedialysis seems to be a major factor related to osteoporosis,it accelerates the pathogenesis of osteoporosis by modulating TNF-α.

Objective To investigate the risk factors,severity and infarct site features and clinical characteristics of the elderly patients over 80 years with cute cerebral infarction.Methods One hundred and sixty-two patients with acute cerebral infarction in Red Cross Hospital of Guangzhou,The Forth Affiliated Hospital of Medical College of Jinan University from January 2012 to May 2015 were enrolled and randomly divided into the elderly patients (≥ 80 years old) and the middle aged patients (＜ 60 years old).The risk factors,national institutes of health stroke scale (NIHSS) scores and Oxfordshire community stroke project (OCSP) criteria were compared between the two groups.Results Coronary artery disease,atrial fibrillation and NIHSS in the elderly patients (25％ (22/88),13.6％ (12/88),7.74 ± 4.986) were significantly higher than those of the middle aged group (12.2％ (9/47),4.1％ (3/74),5.04± 4.305),and the differences were significant (x2 =4.281,4.393,t =-3.649;P＜ 0.05 or P＜ 0.001).The logistic regression analysis finally showed that smoking,hyperlipemia,NIHSS scores and gender(male) were the independent risk factors(OR=3.851,3.609,1.100 and 2.670;P＜0.05).There were more LACI patients in the elderly group than he middle aged group ((40.9％,36/88) vs.(60.8％,45/74),x2 =6.369,P ＜ 0.05).Conclusion Compare to the middle aged patients,occurrence of the elderly patients with acute cerebral infarction is more severe,and the clinical features and risk factors have its particularity.Secondary prevention strategy should be emphasized on the control of different risk factors based on the patients' age.

AIM:To investigate the effect of angiotensin II type 1 receptor (AT1R)-calcineurin (CaN) signa-ling pathway on the expression of sodium current channel Nav 1.5 at mRNA and protein levels in the hypertrophic ventricu-lar myocytes from neonatal rats .METHODS:The ventricular myocytes were isolated from the ventricles of 1-day-old neo-natal Sprague-Dawley rats and were divided into 4 groups according to different drug intervention as control group , pheny-lephrine (PE) group, losartan (Los)+PE group and cyclosporin A (CsA)+PE group.The method of RNA interference mediated by adenovirus carrying short hairpin RNA ( shRNA) was used to knock down the gene which encodes the beta subtype of CaN A subunit (CnAβ) and the cells were divided into 4 groups as Ad-Null group, Ad-Null+PE group, Ad-CnAβshRNA1 group and Ad-CnAβshRNA1+PE group.The mRNA expression of brain natriuretic peptide ( BNP) ,β-my-osin heavy chain (β-MHC) and Nav1.5 was detected by RT-qPCR.The protein levels of CnAβand Nav1.5 in the whole-cell extracts were determined by Western blot analysis .RESULTS:Treatment of the neonatal rat ventricular myocytes with PE for 24 h increased the protein-to-DNA ratio and the mRNA expression of BNP and β-MHC.The size of the cell surface was also increased after PE treatment .Treatment of the cells with PE increased the protein expression of CnAβ, and re-duced the protein expression of Nav 1.5.Both Los and CsA prevented those effects of PE .The mRNA expression of Nav1.5 was reduced by PE , and no significant difference of Nav 1.5 mRNA expression among PE group , Los+PE group and CsA+PE group was observed .Silencing of CnAβin the neonatal rat ventricular myocytes using Ad-CnAβshRNA1 inhibited the ability of PE to increase the mRNA expression of BNP , and diminished the ability of PE to reduce the protein expression of Nav1.5.CONCLUSION:AT1 R-CaN signaling pathway participates in regulating protein expression of Nav 1.5 in the hy-pertrophic ventricular myocytes from neonatal rats .

Objective: To explore the role of angiotensin receptor type I (AT1)-calcineurin (CaN) signaling pathway in transient outward potassium ion channel (Ito) remolding in hypertrophic atrial myocytes of neonatal rats. Methods: 1 day old neonatal rats’ atrial myocytes were isolated and the cells were divided into 4 groups:①Control group, normal cells were cultured for 24 h,②Stretching group, the cells were cultured for 24 h with mechanical stretching to induce hypertrophy,③Telmisartan group, the cells were treated by telmisartan at 1 μmol/L for 1 h, then cultured for 24 h and ④Cyclosporin-A (CsA) group, the cells were treated by CsA at 0.25 μg/ml for 1 h, then cultured for 24 h. The ratios of protein/DNA in myocytes were compared between Control group and Stretching group, cell hypertrophy was deifned by mRNA expression of atrial natriuretic peptide (ANP). Ito changes were detected by whole-cell patch clamping technique, proteins expressions of Kv4.3 and CaN A subunit were examined by Western blot analysis. Results: Compared with Control group, Stretching group showed obviously decreased Ito density and Kv4.3 protein expression, while increased CaN A protein expression; Compared with Stretching group, the above effects were reduced in Telmisartan group and CsA group. Conclusion: AT1-CaN signaling pathway was involved in the regulation of Ito channel remodeling in hypertrophic atrial myocytes of neonatal rats.