BACKGROUND:We have successfuly prepared digital coraline hydroxyapatite artificial bone scaffold in previous experiments, and it has been confirmed that it has the necessary physical and chemical properties of bone tissue engineering scaffolds. OBJECTIVE: To evaluate the sensitization of digital coraline hydroxyapatite artificial bone scaffold. METHODS:A total of 32 guinea pigs were randomly divided into saline group (negative control group, n=8), 5% formaldehyde group (positive control group,n=8), experimental A group (the mass ratio of 3:1,n=8), and experimental B group (the mass ratio of 4:1,n=8). Sensitization test at the maximal dosage was performed according toBiological Evaluation of Medical Devices-Part 10: Tests for Irritation and Delayed-Type Hypersensitivity, including intracutaneous induction, local induction, and provocation. Patch was removed after 24 and 48 hours, and the skin response was classified according to Magnusson and Kligman criteria. Patch was removed after 48 hours, and the skin was performed with biopsy, stained with hematoxylin-eosin, and observed under optical microscope. RESULTS AND CONCLUSION: Sensitization response was not tested in the negative control group, experimental A group and experimental B group at 24 and 48 hours after patch removal; however, moderate erythema was observed in the positive control group. Optical microscope demonstrated that spongiosis, edema, diffuse or perivascular mononuclear infiltration was not observed, and only a smal number of basicytes were seen in the experimental A and B groups. These findings indicate that the digital coral hydroxyapatite artificial bone scaffolds, with the mass ratio of 3:1 and 4:1, are biologicaly safe for sensitization.

Objective To observe whether calreticulin-induced mitochondrial dysfunction is involved in cardiomyocyte hypertrophy induced by angiotensin Ⅱ (AngⅡ).Methods Primary culture of neonatal rat cardiomyocytes was further confirmed by immunocytochemistry.The cardiomyocytes were randomly divided into model group,valsartan group and control group.The model group was subdivided into three groups which were separately treated with 1 0-8 mmol/L, 1 0-7 mmol/L, and 1 0-6 mmol/L Ang Ⅱ. Calreticulin expression, mitochondrial membrane potential level, enzyme activities, cell surface area and protein synthesis rate were observed.Results Cell surface area and protein synthesis rate were both increased in model groups compared with control group.Mitochondrial membrane potential level and enzyme activities were lower in model groups than in control group,while calreticulin expression was up-regulated.Pretreatment with valsartan partially reversed all the above changes.Conclusion Mitochondrial dysfunction induced by calreticulin may be an important mechanism of myocardial hypertrophy.

[ ABSTRACT] AIM:To observe the effect of high glucose on the protein expression of calreticulin ( CRT) and its association with cell apoptosis and mitochondrial dysfunction in the cardiomyocytes.METHODS: AC-16 cardiomyocytes were randomly divided into normal glucose group, high glucose group, high glucose+CRT siRNA group and isotonic con-trol group.The cell apoptotic rate, reactive oxygen species (ROS), mitochondrial membrane potential level, respiratory enzyme activity, and protein expression of CRT were observed.RESULTS: Compared with the cardiomyocytes in normal glucose group, the apoptotic rate and ROS production of cardiomyocytes increased in high glucose group, accompanying with the decreases in the mitochondrial membrane potential level and enzyme activitiy of the respiratory chain.The protein expression of CRT was significantly increased in high glucose group.However, compared with high glucose group, high glucose+CRT siRNA decreased the expression of CRT and attenuated the damage of mitochondria, but CRT siRNA did not reduce the ROS level in cardiomyocytes.CONCLUSION:High glucose brings about CRT over-expression to induce mito-chondrial injury, thus increasing myocardial apoptosis.

Objective To explore the changes of cardiac structure and function in streptozotocin (STZ)-induced diabetic cardiomyopathy (DCM)rats so as to detect the level of angiotensinⅡ (AngⅡ)in blood and the myocardium and illuminate the role of AngⅡ in DCM.Methods We randomly divided 30 SD rats into control group and DCM group (which received a single injection of streptozotocin,65 mg/kg).The changes of cardiac structure and function were observed by ultrasonic cardiogram at the end of 16 weeks after injection.Then the changes in the myocardium were also analyzed by using hemotoxylin and eosin staining and Sirius red staining.The level of AngⅡ in blood was tested by radioimmunoassay.The expression of AngⅡ in the myocardium was detected by immunofluorescence. Results Compared with those of the controls,the hearts were dilated in DCM rats accompanied with cardiac dysfunction.There were significant increases in LVEDd,LVESd,LVEDv,and LVESv but decrease in LVEF (P <0.05).There were arrangement disorder and hypertrophic cardiomyocytes in DCM.Then the fibrosis area of DCM was significantly increased compared with that of the controls.The level of AngⅡ in blood and myocardium was significantly higher in DCM than in controls.At the same time,Pearson analysis revealed that the level of AngⅡ in blood was positively related to the collagen content of myocardium (r =0.907,P <0.05).Conclusion Our study provides experimental evidence that AngⅡ plays an important role in myocardial fibrosis of DCM.

OBJECTIVETo construct an eukaryotic expression vector for vascular endothelial growth factor (VEGF) 165 gene and obtain VEGF expression in rat bladder smooth muscle cells.

METHODSVEGF165 cDNA was cloned into the eukaryotic expression vector pcDNA3.1(-), and the resultant recombinant vector pcDNA3.1(-)/VEGF165 was transfected into the rat bladder smooth muscle cells by electroporation. VEGF expression in the cells was determined by RT-PCR and immunofluoresence assay, and the biological activity of VEGF in the supernant of the transinfected cell culture was tested by MTT assay.

RESULTS AND CONCLUSIONVEGF expression was obtained in the transinfected cells, and the supernant of the transinfected cell cultures stimulated the proliferation of the endothelial cells.

Animals ; Animals, Newborn ; Cell Line ; Cell Proliferation ; drug effects ; Cells, Cultured ; Cloning, Molecular ; Culture Media, Conditioned ; metabolism ; pharmacology ; DNA, Complementary ; genetics ; Eukaryotic Cells ; metabolism ; Fluorescent Antibody Technique ; Gene Expression ; Genetic Vectors ; genetics ; Humans ; Myocytes, Smooth Muscle ; cytology ; metabolism ; Rats ; Reverse Transcriptase Polymerase Chain Reaction ; Transfection ; Urinary Bladder ; cytology ; Vascular Endothelial Growth Factor A ; genetics ; metabolism ; pharmacology

OBJECTIVETo observe the risk factor stratification and prevalence of target organ damage in hypertensive patients before therapy and blood pressure control rate after 4 or 12 weeks antihypertensive drug therapy.

METHODSIn this prospective survey, data on cardiovascular risk factors, target organ damage and concomitant disease were collected in 26 655 hypertensive patients. Among them 26 325 and 3457 patients were recruited for antihypertensive drug therapy for 4 and 12 weeks, respectively and blood pressure control rate was determined.

RESULTSThe sedentary lifestyle, smoking, high body mass index, dyslipidemia were found in 52.5%, 34.4%, 31.8%, 24.5%, and microproteinuria, left ventricular hypertrophy, coronary artery disease and diabetes in 21.0%, 23.6%, 20.1%, 26.7% hypertensive patients, respectively. The average systolic and diastolic pressures were 158 +/- 14 mm Hg and 94 +/- 11 mm Hg and 3.2%, 22.2%, 21.1% and 53.3% patients were defined as low, medium, high and very high risk patients in risk stratification to quantify prognosis. There were 77.2%, 20.4% and 2.4% systolic and diastolic, isolated systolic and isolated diastolic hypertensive patients respectively. The goal blood pressure control rate was 50.2% and 56.7% respectively after 4 and 12 weeks antihypertensive drug therapy. The control rate in patients complicated with diabetes and renal disease was significantly lower than patients without them and systolic pressure control rate was remarkably lower than diastolic pressure control rate. Majority patients required 2 or more antihypertensive drugs for effective pressure control (1.5 drug per patients in average in both 4 or 12 weeks groups).

CONCLUSIONThe prevalence of risk factors, target organ damage and concomitant disease were high in Chinese patients with hypertension and comprehensive interventions were indicated. To reach goal blood pressure control in patients with hypertension, follow up intensifying and drug therapy guidance are required within the context of usual medical care.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; China ; Female ; Humans ; Hypertension ; prevention & control ; therapy ; Male ; Middle Aged ; Prognosis ; Prospective Studies ; Risk Factors ; Treatment Outcome ; Young Adult

Adult ; Aged ; Aged, 80 and over ; Female ; Humans ; Male ; Manipulation, Orthopedic ; methods ; Middle Aged ; Shoulder Dislocation ; therapy

OBJECTIVETo study the phosphorylation activity of mitochondrial signal transducer and activator of transcription 3 (STAT3) in the myocardium of rats with selenium deficiency and its association with myocardial injury.

METHODSThirty-six rats were randomized into normal control group (n=18) and selenium deficiency model group (n=18) for feeding with normal and low-selenium chow, respectively, for 20, 30 and 40 weeks. The cardiac function of the rats was evaluated by carotid artery intubation, and the damage of cardiac mitochondria was observed under electron microscopy. The cardiac mitochondria were extracted for assessing succinate dehydrogenase and cytochrome C oxidase activities, and the protein expressions of phosphorylated and total STAT3 were detected.

RESULTSCompared with the corresponding control groups, the rats in the model group showed significantly decreased cardiac function with obvious structural and functional damage of the cardiac mitochondria (P<0.05), which aggravated as the low-selenium feeding time extended (P<0.05). The rats in the model group also showed significantly decreased mitochondrial STAT3 activity (p-STAT3/STAT3) in the myocardium as the low-selenium feeding time prolonged (P<0.05). Pearson linear correlation analysis showed that the activity of cardiac mitochondrial STAT3 had positive correlations with the left ventricular systolic pressure, maximal increased rate of the left ventricular pressure, and the activities of succinate dehydrogenase and cytochrome C oxidase (P<0.01).

CONCLUSIONSelenium deficiency down-regulates the activity of mitochondrial STAT3 in rat heart to contribute to cardiac mitochondrial injury and the progression of heart failure.

Animals ; Diet ; Electron Transport Complex IV ; metabolism ; Female ; Heart Injuries ; metabolism ; Male ; Mitochondria, Heart ; drug effects ; metabolism ; Rats ; Rats, Sprague-Dawley ; STAT3 Transcription Factor ; metabolism ; Selenium ; deficiency ; pharmacology ; Signal Transduction ; Succinate Dehydrogenase ; metabolism

OBJECTIVE: To investigate the expressions and time-dependent changes of phosphatidylinositol-3-kinase (PI3K), phospho-PI3K (p-PI3K), protein kinase B (PKB/Akt) and phospho-Akt (p-Akt) during wound healing process of mice skin. METHODS: The changes of PI3K, p-PI3K, Akt and p-Akt expression in skin wound were detected by immunohistochemistry, Western blotting and real-time PCR. RESULTS: Immunohistochemistry showed the expression of PI3K and p-Akt were observed in mononuclear and fibroblast after skin wound, and reached peak in reconstruction. The positive bands of PI3K, p-PI3K, Akt and p-Akt were observed in all time points of the wound healing process by Western blotting. The expression peak of p-PI3K and p-Akt showed in inflammation and proliferation; the expression peak of PI3K and Akt in reconstruction. Real-time PCR showed the expression peak of PI3K mRNA in inflammation and reconstruction and the peak of Akt mRNA in reconstruction. CONCLUSION During the wound healing process, the expressions of PI3K, Akt, p-PI3K and p-Akt show different changes with significant correlation to wound time. The expression of PI3K/Akt may be a valuable marker for wound time estimation.
Animals ; Blotting, Western ; Class I Phosphatidylinositol 3-Kinases ; Fibroblasts/metabolism* ; Mice ; Phosphatidylinositol 3-Kinase ; Phosphatidylinositol 3-Kinases/metabolism* ; Phosphorylation ; Proto-Oncogene Proteins c-akt/metabolism* ; Real-Time Polymerase Chain Reaction ; Signal Transduction ; Skin/injuries* ; Wound Healing