1.Effect of high glucose and anoxia on Amot expression in vascular endothelial cells with regard to its function in promoting angiogenesis
Yuejie CHU ; Penghua WANG ; Daiqing LI ; Demin YU
Chinese Journal of Endocrinology and Metabolism 2014;30(5):428-431
Objective To observe the effects of high glucose and anoxia on Amot expression in vascular endothelial cells (VECs),and explore its role in angiogenesis.Methods VECs were incubated with different glucose concentrations for 48 h,and then cultured at normal oxygen concentration or anaerobic condition for 24 h.The protein expressions of p130-Amot and p80-Amot were detected by Western blot.After Amot expression was downregulated in VECs by siRNA,wound healing experiments and angiogenesis experiments were performed to test the effect of decreased Amot expression on angiogenesis.Results pl30-Amot protein expressions in low glucose (5.5mmol/L) plus normal oxygen group and low glucose plus anaerobic group were higher than those in high glucose (30mmol/L) plus normal oxygen group,high glucose plus anaerobic group,middle glucose (15 mmol/L) plus normal oxygen group,and middle glucose plus anaerobic group (all P<0.01).Compared with low glucose plus anaerobic group,p130-Amot expression was higher in low glucose plus normal oxygen group (P < 0.01).However,the expression of p80-Amot showed no statistically significant difference among different groups (P>0.05).Compared to the normal VECs,the cells with decreased Amot expression by siRNA exhibited an attenuated cell migration in the wound healing experiments and a lesser tube formation in the angiogenesis experiments.Conclusions High glucose exerts a more significantly negtive effect on the Amot expression than anoxia in VECs.The downregulation of Amot expression inhibits migration and angiogenesis of VECs.
2.Repair of ulcer with rhEGF sustained-release microspheres in diabetic rats
Yuejie CHU ; Demin YU ; Penghua WANG ; Yingfang TIAN ; Jun XU ; Jin CHANG ; Daiqing LI ; Min DING
Chinese Journal of Trauma 2009;25(9):783-787
Objective To prepare recombinant human epidermal growth factor (rhEGF) sustained-release microspheres and evaluate their morphology, rhEGF releasing activities and cell proliferation activity in vitro and compare difference of rhEGF sustained-release microspheres and rhEGF in facilitaring ulcer healing in diabetic rats. Methods (1) rhEGF sustained-release microspheres were prepared by the modified double emulsion method. Morphology of the microspheres was detected by transmission electron microscope and size distribution measured by laser granularity meter/Zeta electric potential meter. ELISA assays were applied to determine rhEGF releasing. (2)Proliferation of mouse fibroblasts was analyzed by MTr method. (3) Diabetic rat models were prepared and divided into four groups, ie, rhEGF sustained-release mierospheres group (Group A), rhEGF stock solution group (Group B), blank sustainedrelease mierospheres group (Group C) and PBS meustruum control group (Group D), which were given drug once a day. The wound healing rate was calculated by taking photographs at days 3,7,14 and 21. Skin specimens from the wound edge were harvested partially for observation of hydroxyproline (HYP) contents. Immunohistochemistry was employed to detect integrin 131 and keratin-19 and measure their positive staining area ratio. Results (1) The particle diameter of rhEGF sustained-release microspheres was 193.5 nm, with relative uniform particle diameter distribution. There showed no conglutination among rhEGF susrained-release microspheres, with good dispersibility. Releasing drug lasted for 24 hours and accorded with Higuchi release kinetic model. (2) Different concentrations of rhEGF sustained-release microspheres could promote the proliferation of mouse fibroblast, especially the concentration of 10 μg/L (P <0.05, compared with the control). (3) From the 7th day after treatment, Group A had the fastest wound healing rate, with statistical difference compared with other three groups (P < 0.05). Group A had higher HYP contents and positive area ratio of integrin β1 and keratin-19 than Group B. Conclusions rhEGF sustained-release microspheres prepared by the modified double emulsion method have uniform particle size and can last release for 24 hours. Compared with rhEGF stock solution, rhEGF sustained-release microspheres have faster and better ulcer healing and higher healing quality in diabetic rats.
3.SCCmec genotypes of methicillin-resistant Staphylococcus epidermidis in diabetic foot infections
Qun DING ; Penghua WANG ; Yuejie CHU ; Shuhong FENG ; Shuyou MENG ; Qian SUN ; Daiqing LI
Chinese Journal of Microbiology and Immunology 2011;31(1):51-54
Objective To investigate SCCmec genotypes and drug-resistance profiles of the methieillin-resistant Staphylococcus epidermidis (MRSE) strains isolated from the patients suffered from diabetic foot infections (DFI) in the Tianjin Metabohc Diseases Hospital. Methods After dabridement, specimens of 390 infectious diabetic foot ulcers in the hospital from Jan 2008 to Jun 2010 were collected from the wound basal parts by cotton swab for culture. The disk-diffusion method was performed to examine antimicrobial susceptibility. DNAs of the MRSE strains were extracted, and their SCCmec genotypes were identified by PCR. Results Twenty of the seventy(28.6% ,20/70)Staphylococcus epidermidis strains were mecA posifive. Among the MRSE isolates, 2 ( 10.0% )were SCCmec Ⅱ ,9 (45.0%)were SCCmecⅢ and 9 (45.0%)were SCCmec Ⅳ. None of the isolates were genotyped as SCCmec Ⅰ or Ⅴ. No mater which genotypes they were, all the MRSE isolates were multi-drug resistant. They were resistant not only to β-lactams (including penicillins, cefoxitin and cephems), but also to non-β-lactams (including macrolides, fiuoroquinolones and sulfonamides ) . Resistance to voncomycin and rifampicin were not found in these strains . Conclusion SCCmec Ⅲ and SCCmecⅣ are major genotypes of the MRSE isolates from the infectious diabetic foot ulcers.The SCCmec Ⅳ genotype strains with multi-drug resistant profiles are prevalent in the diabetic foot infections.
4.Expression and significance of caveolin-1 in femoral nerve of diabetic foot amputation patients
Min DING ; Yuejie CHU ; Jun XU ; Mingfang ZHANG ; Fengyun ZHAO ; Penghua WANG
Chinese Journal of Endocrinology and Metabolism 2010;26(10):854-858
Objective To investigate the expression and significance of caveolin-1 in femoral nerve of diabetic patients with foot amputation. Methods Forty patients with foot amputation were assigned to 3 groups according to their duration of type 2 diabetes: group A ( <6 years=, group B (6-10 years), and group C ( >10 years). Hematoxylin and eosin (HE) stain and Weil's stain were used to examine the femoral nerve. Silver staining was used to observe the axons and to count the nerve fiber density. The expression of caveolin-1 in Schwann cells of femoral nerve was tested by immunohistochemisty. Results There were evident progressive pathological changes in femoral nerve in the 3 groups. The variance of nerve fiber density in the 3 groups reached statistical significance ( P<0. 05 =, the nerve fiber density showed negative correlation with HbA1C( r =-0. 792, P<0. 01 = and duration ( r=-0.592, P<0. 01 =. The expression of caveolin-1 in Schwann cells of femoral nerve was positive in all the 3 groups and the variance with statistical significance (P<0. 01 ), it was negatively correlated with HbA1C (r=-0. 762, P<0. 01 )and duration (r=-0. 532, P<0. 01 ), and it was positively correlated with nerve fiber density (r=0. 721, P<0.01 ), the partial correlation coefficient of caveolin-1 and HbA1Cwas-0. 505 ( P<0. 01 ).Conclusion In patients with diabetic foot amputation, caveolin-1 may play a role in the development of diabetic peripheral neuropathy and diabetic foot.
5.Study on the safety and effectiveness of an exercise prescription for patients with diabetic foot ulcer and peripheral arterial disease
Congcong ZHENG ; Penghua WANG ; Yuejie CHU ; Min DING ; Haojie SUN ; Jie GUO
Chinese Journal of Endocrinology and Metabolism 2013;(1):18-23
Objective To investigate the effect of exercise prescription on foot perfusion and ulcer healing in patients with diabetic foot ulcer (DFU) accompanied with peripheral arterial disease (PAD).Methods Sixty patients with DFU and PAD were divided into exercise group and control group.The patients in the exercise group took exercise therapy training,ensuring that they could follow the exercise prescription.The patients in the control group had no exercise requirements.After the treatment for 12 weeks,ankle brachial index (ABI),transcutaneous oxygen tension (TcPO2),skin temperature,body mass index (BMI),HbA1C,and the ulcer healing rate in the two groups were compared,the satisfaction and compliance in the exercise group were evaluated,and the adverse events of the treatment were recorded.Results After the treatment for 12 weeks,the ABI,TcPO2,and foot skin temperature in the two groups increased and HbA1C decreased(P<0.05 or P<0.01).TcPO2 increased 5.25 mm Hg(1 mm Hg=0.133kPa),skin temperature increased 0.45℃,and BMI decreased 0.69 kg/m2 in the exercise group,while TcPO2 increased 2.59 mm Hg,skin temperature increased 0.28℃,and BMI increased 0.02 kg/m2 in the control group,showing significant differences in the three index changes between two groups (P<0.01).The healing rate in the exercise group was higher than that in the control group (53.6% vs 25.9%,P <0.05).The patients'compliance and satisfaction to the exercise therapy were 90% and 94%,respectively.The incidence of adverse events in the exercise group had no causal relationship with the exercise prescription.Conclusion The exercise prescription in the study can improve the foot perfusion,and promote ulcer healing.It has the advantage of high safety,patients'compliance and satisfaction.
6.Clinical features and drug resistance of pseudomonas aeruginosa isolates from patients with diabetic foot infections
Qian SUN ; Penghua WANG ; Yuejie CHU ; Da ZHANG ; Qun DING ; Shuyou MENG ; Wei YANG ; Qian LIU ; Daiqing LI
Chinese Journal of Endocrinology and Metabolism 2012;28(10):817-820
Objective To investigate clinical features and antibiotic resistance of pseudomonas aeruginosa (PA) strains isolated from patients with diabetic foot infections (DFI) in Tianjin Metabolic Diseases Hospital.Methods Eighty-five PA strains were isolated from 428 patients with diabetic foot in the hospital from Jan 2008 to Dec 2010.The clinical features of patients were summarized.Relationships between the isolates and depth of ulcer or severity of infection were analyzed.The disk-diffusion method was performed to examine antimicrobial susceptibility.Results Gram positive (G+) and Gram negative (Gˉ) isolates were 50.47% and 41.12%,respectively.Multidrug-resistant PA composed 32.9% of the total PA isolates.The size of ulcers with PA infections was bigger than those with non-PA bacterial infections (P<0.05).Compared to G+ strains,patients with PA strains were older,had lower hemoglobin,but higher serum sensitive C-reactive protein; and more frequently,they had ischemic ulcer and osteomyelitis.Compared to G+ strains,the PA strains were more frequently isolated from deeper ulcers and with more serious infections(P<0.05).The resistant rates of PA to cephalosporins,fluoroquinolones,and aminoglycosides were between 32.9%-61.2%,37.6%-42.4%,and 37.6%-62.4%,respectively.Only one out of 85 PA strains was imipenem-resistant.However,sensitiveness of all PA isolates to cefoperazone and sulbactam reached 100%.Conclusion PA strains are mainly found in patients with deeper ulcers and more serious infections.Multidrug-resistant PA is common in DFI.It is important to isolate pathogens and determine their antibiotic resistance correctly in diabetic foot patients in order to provide appropriate drug administration and to reduce the production and dissemination of drug resistant strains.