OBJECTIVE This study evaluates the role of Gelation metnacrylate(GelMA)hydrogel loaded with hPT H(3-34)(29-34)short peptide in the healing of chronic infectious skin wounds in diabetic rats.METHODS Ex-perimental rats were divided into control group,GelMA group and GelM A+hPTH(3-34)(29-34)group,with 15 rats in each group.Diabetic rat models were prepared,and chronic infectious skin wounds were constructed.Differences in wound area changes,wound healing-related indicator[type Ⅰ collagen α1 chain(COL1A1),α-smooth muscle actin(α-SMA),platelet endothelial cell adhesion molecule-1(CD31),matrix metalloproteinase-9(MMP9)and cyclooxygenase-2(Cox2)]expression and migration ability of fibroblasts in vitro were compared a-mong the groups.RESULTS Compared with the control group,the wound area of rats in the GelMA group de-creased on Day 7 and Day 14(P＜0.05),and the wound area of rats in the GelM A+hPTH(3-34)(29-34)group decreased on Day 3,Day 7 and Day 14(P＜0.05).Compared with the GelMA group,the wound area of rats in the GelM A+hPTH(3-34)(29-34)group decreased on Day 3,Day 7 and Day 14(P＜0.05).Compared with the control group,on Day 7 after modeling,the expression of COL1A1,α-SMA and CD31 in rats was upregulated,and in the GelM A+hPTH(3-34)(29-34)group showed a greater increase than in the GelMA group(P＜0.05),while the expression of MMP9 and Cox2 was downregulated,and in the GelMA+hPTH(3-34)(29-34)group showed a greater decrease than in the GelMA group(P＜0.05).Compared with the control group,on Day 7 af-ter modeling,the relative activity of NLRP3,IL-6,TNF-α,IL-1β and Caspase-1 in rats decreased,and in the GelM A+hPTH(3-34)(29-34)group showed a greater decrease than in the GelMA group(P＜0.05).On Day 7 after modeling,the relative scratch distance of fibroblasts derived from the wound tissue in the GelMA+h PT H(3-34)(29-34)group was greater than that in the GelMA group,which was greater than that in the control group(P＜0.05).CONCLUSIONS The GelMA hydrogel loaded with hPTH(3-34)(29-34)short peptide can effectively accelerate the wound healing process and enhance tissue repair and structural reconstruction by inhibiting the activ-ity of the NLRP3 inflammasome pathway,demonstrating its potential to improve wound healing efficiency.

OBJECTIVE This study evaluates the role of Gelation metnacrylate(GelMA)hydrogel loaded with hPT H(3-34)(29-34)short peptide in the healing of chronic infectious skin wounds in diabetic rats.METHODS Ex-perimental rats were divided into control group,GelMA group and GelM A+hPTH(3-34)(29-34)group,with 15 rats in each group.Diabetic rat models were prepared,and chronic infectious skin wounds were constructed.Differences in wound area changes,wound healing-related indicator[type Ⅰ collagen α1 chain(COL1A1),α-smooth muscle actin(α-SMA),platelet endothelial cell adhesion molecule-1(CD31),matrix metalloproteinase-9(MMP9)and cyclooxygenase-2(Cox2)]expression and migration ability of fibroblasts in vitro were compared a-mong the groups.RESULTS Compared with the control group,the wound area of rats in the GelMA group de-creased on Day 7 and Day 14(P＜0.05),and the wound area of rats in the GelM A+hPTH(3-34)(29-34)group decreased on Day 3,Day 7 and Day 14(P＜0.05).Compared with the GelMA group,the wound area of rats in the GelM A+hPTH(3-34)(29-34)group decreased on Day 3,Day 7 and Day 14(P＜0.05).Compared with the control group,on Day 7 after modeling,the expression of COL1A1,α-SMA and CD31 in rats was upregulated,and in the GelM A+hPTH(3-34)(29-34)group showed a greater increase than in the GelMA group(P＜0.05),while the expression of MMP9 and Cox2 was downregulated,and in the GelMA+hPTH(3-34)(29-34)group showed a greater decrease than in the GelMA group(P＜0.05).Compared with the control group,on Day 7 af-ter modeling,the relative activity of NLRP3,IL-6,TNF-α,IL-1β and Caspase-1 in rats decreased,and in the GelM A+hPTH(3-34)(29-34)group showed a greater decrease than in the GelMA group(P＜0.05).On Day 7 after modeling,the relative scratch distance of fibroblasts derived from the wound tissue in the GelMA+h PT H(3-34)(29-34)group was greater than that in the GelMA group,which was greater than that in the control group(P＜0.05).CONCLUSIONS The GelMA hydrogel loaded with hPTH(3-34)(29-34)short peptide can effectively accelerate the wound healing process and enhance tissue repair and structural reconstruction by inhibiting the activ-ity of the NLRP3 inflammasome pathway,demonstrating its potential to improve wound healing efficiency.

Objective:To explore the consistency of peripheral whole blood and venous serum procalcitonin (PCT) levels, and the value of peripheral whole blood PCT in evaluating pediatric bacterial infection.Methods:This multicenter cross-sectional parallel control study was conducted in 11 children′s hospital. All the 1 898 patients older than 28 days admitted to these hospitals from March 2018 to February 2019 had their peripheral whole blood and venous serum PCT detected simultaneously with unified equipment, reagent and method. According to the venous serum PCT level, the patients were stratified to subgroups. Analysis of variance and chi-square test were used to compare the demographic characteristics among groups. And the correlation between the peripheral blood and venous serum PCT level was investigated by quantitative Pearson correlation analysis.The PCT resultes were also converted into ranked data to further test the consistency between the two sampling methods by Spearman′s rank correlation test. Furthermore, the ranked data were converted into binary data to evaluate the consistency and investigate the best cut-off of peripheral blood PCT level in predicting bacterial infection.Results:A total of 1 898 valid samples were included (1 098 males, 800 females),age 27.4(12.2,56.7) months. There was a good correlation between PCT values of peripheral whole blood and venous serum ( r=0.97 , P<0.01). The linear regression equation was PCT?venous serum=0.135+0.929×PCT peripheral whole blood. However, when stratified to 5 levels, PCT results showed diverse and unsatisfied consistency between the two sampling methods ( r=0.51-0.92, all P<0.01). But after PCT was converted to ordinal categorical variables, the stratified analysis showed that the coincidence rate of the measured values by the two sampling methods in each boundary area was 84.9%-97.1%. The dichotomous variables also showed a good consistency (coincidence rate 96.8%-99.3%, Youden index 0.82-0.89). According to the severity of disease, the serum PCT value was classified into 4 intervals（<0.5、0.5-<2.0、2.0-<10.0、≥10.0 μg/L）, and the peripheral blood PCT value also showed a good predictive value (AUC value was 0.991 2-0.997 9). The optimal cut points of peripheral whole blood PCT value 0.5、1.0、2.0、10.0 μg/L corresponding to venous serum PCT values were 0.395, 0.595, 1.175 and 3.545 μg/L, respectively. Conclusions:There is a good correlation between peripheral whole blood PCT value and the venous serum PCT value, which means that the peripheral whole blood PCT could facilitate the identification of infection and clinical severity. Besides, the sampling of peripheral whole blood is simple and easy to repeat.

Objective To explore the effects of gossypol acetate on the morphological features and the gene expression in the femoral head of Sprague-Dawley rat in vivo after treated with dexamethasone .Methods Dexamethasone(Dex) was injected into the abdominal cavity of SD rats at an dose of 10 mg/kg ,twice a week ,and feed gossypol acetate 5 mg · kg -1 · d-1 .The controls re-ceived saline 2 mL injection .The treatment lasted for 12 and 20 weeks .The slices of the femoral head were made for HE and immu-nohistochemical study .The total mRNA was extracted for RT-PCR assessment .Results The cancellous bone trabecular became sparse ,trabecular bone area ratio decreased ,bone marrow fat tissue increased .These changes were fitted for pathological character of bone necrosis .The gossypol acetate could not affect the pathological changes .The proportion of the positive stained osteoblasts increased ,adipocytes decreased .PPARγ,C/EBPα,11β-HSD1 expression enhanced ,Runx2 down regulated in the treatment groups and GAA group .Conclusion Dex can induce evident pathological changes conform to the characters of femoral head necrosis .They may have closed correlation between 11β-HSD1 and the gene expression .But GAA could not affected the pathological changes and abnormality of the gene expression .