Objective:To compare the effect of three different titanium alloy surface topographies on the biological character fibro-blasts.Methods:Three different titanium alloy Ti6Al4V surface topographies were created by machining(M),direct current electro-chemical etching(DC)and alternating current electrochemical etching(AC)respectively,and standard sized samples were prepared. The surface topographies were observed field emission scanning electron microscopy(FE-SEM).Mouse L929 fibroblasts were cultured on different surfaces.The attachment of cells was examined by acridine orange staining and observed under fluorescent microscope.The proliferation of cells was measured using MTT assay.Results:Tubles with the diamete of 5 -20 μm were observed on the surface of the sample of group DC,and more evenly distributed tubles on that of group AC.Micro-sulci were observed and no microtuble was found on the sample surface of group M.L929 cells were attached on the surface of all the samples in the 3 groups.More adhered and better strached cells were observed on AC treated surface.The proliferation of fibroblasts on AC and DC surfaces was superior to that on M treated surface and at the 3 -5 day the proliferation of fibroblasts on the AC surface was higher than that on DC treated surface.Con-clusion:AC treated surface with the micro-submicro-nano hierarchical topography of titanium alloy has a superior biocompatibility and can promote the early attachment and proliferation of the fibroblasts.

Objective:To prospectively investigate the prevalence of heparin-induced thrombocytopenia (HIT) in critically ill children during extracorporeal membrane oxygenation(ECMO) and explore the clinical characteristics and prognosis of HIT during ECMO.Methods:A total of 22 critically ill children, who had received ECMO support for more than 96 hours in the Intensive Care Unit at the Children′s Hospital of Fudan University from March 2019 to December 2020, were enrolled.According to the 4T score and the heparin/platelet factor 4(PF4) antibody, children whose 4T scores were not less than 6 and heparin/ PF4 antibodies were positive, were classified into HIT group ( n=6), and non-HIT group ( n=16). The clinical outcomes and the incidence of thrombotic events were compared between two groups. Results:The incidence of HIT during ECMO in critically ill children was 27% in this study.The incidence of thrombosis in the ECMO circuit in the HIT group was higher (100% vs.63%, P=0.133), and the average time to the first thrombosis in ECMO circuit in the HIT group was shorter than that in the non-HIT group (3.70 d vs.5.44 d, P=0.06). During the first 14 days of ECMO, the proportion of children with thrombotic events no less than twice was higher in the HIT group (67% vs.19%, P=0.054). There was no significant difference regarding the survival rate at 28 days after ECMO withdrawal between two groups (33% vs.50%, P=0.664). Conclusion:The prevalence of HIT during ECMO in critically ill children is high.Thrombosis events tend to occur earlier and more extensively in children with HIT during ECMO.No significant effect of HIT on the survival rate of children during ECMO is found.Whether HIT has effect on the survival rate of children with ECMO requires a prospective and large clinical study.

Objective:To explore the high-risk factors for parenteral nutrition associated cholestasis（PNAC）in extremely/ultra-low birth weight infants，and establish a risk Alignment Diagram prediction model.Methods:We retrospectivly analyzed the clinical data of hospitalized extremely/ultra-low birth weight infants admitted to Neonatology Department at Quanzhou Children's Hospital from January 2019 to December 2020，using multivariate Logistic regression analysis to screen for independent risk factors for the occurrence of PNAC.An Alignment Diagram model prediction model for PNAC was constructed by using R software，and the performance of the model was evaluated through receiver operating characteristic curves.Results:A total of 203 extremely/ultra-low birth weight infants were included，with a median gestational age of 29.14（28.00，30.86）weeks and a median birth weight of 1　170（1　000,1　300）g.Among them，26（12.81%）cases developed PNAC.Multivariate Logistic regression analysis showed that the duration of parenteral nutrition（ OR=1.015 ，95% CI 1.003-1.034），the cumulative amount of glucose（ OR=1.014 ，95% CI 1.001-1.028），small for gestational age（ OR=3.455 ，95% CI 1.127-10.589），and neonatal sepsis（ OR=3.142 ，95% CI 1.039-9.503）were independent risk factors for PNAC（ P＜0.05）；The four independent risk factors mentioned above were introduced into R software to construct an Alignment Diagram model，the area under the receiver operating characteristic curve was 0.835（95% CI 0.842-0.731），and the results of the Hosmer Limeshow goodness of fit test show that：χ 2=5.34，degree of freedom=8， P=0.72.A calibration curve indicated good consistency between the predicted probability of the model and the actual occurrence rate，with good accuracy. Conclusion:The Alignment Diagram model constructed based on four independent risk factors of the duration of parenteral nutrition，glucose accumulation，small for gestational age infants，and neonatal sepsis exhibits high predictive ability，and is expected to provide an intuitive and convenient visualization tool for preventing or reducing the occurrence of PNAC in extremely/ultra-low birth weight infants

Objective:To examine the value serum calcium and intact parathyroid hormone (iPTH) levels measured on the first day after total thyroidectomy on prediction for permanent hypoparathyroidism.Methods:Totally 546 patients with thyroid cancer and benign thyroid lesions who underwent total thyroidectomy at Department of General Surgery, Beijing Chaoyang Hospital, Capital Medical University from February 2008 to December 2018 were analyzed retrospectively. There were 158 males and 388 females aging (50.9±13.2) years (range: 19.0 to 79.2 years). Serum calcium and iPTH levels were collected before surgery, on the first day and 6 months after surgery. Logistic regression was used to analyze the correlation between each data and the occurrence of permanent hypoparathyroidism after surgery.The area under the receiver operating characteristic curve was used to evaluate the predictive power of iPTH for postoperative occurrence of permanent hypoparathyroidism.Results:Among the 546 cases of total thyroidectomy, 22 cases of permanent hypoparathyroidism occurred, with an incidence of 4.0% (22/546). Multivariate analysis showed that iPTH levels on the first day after total thyroidectomy ( OR=2.932, 95 %CI: 1.129 to 7.616, P=0.027) and serum calcium levels ( OR=2.584, 95 %CI: 1.017 to 6.567, P=0.046) were independent prognosis factors for postoperative permanent hypoparathyroidism. When the threshold value of iPTH at 24 hours after total thyroidectomy was 5.51 ng/L, the AUC was 0.956 (95 %CI: 0.936 to 0.972, P=0.000), sensitivity was 100%, specificity was 85.1%, positive predictive value was 22%, negative predictive value was 100%. When the threshold value of serum calcium at 24 hours after total thyroidectomy was 1.93 mmol/L, the AUC was 0.733 (95 %CI: 0.694 to 0.770, P=0.000), sensitivity was 63.6%, specificity was 78.1%, positive predictive value of 10.8% and negative predictive value of 98.1%. Conclusions:Serum iPTH and calcium levels on the first day after total thyroidectomy were related to the occurrence of permanent hypoparathyroidism postoperatively. The predictive value of iPTH level is higher than that of serum calcium level.

Objective:To examine the value serum calcium and intact parathyroid hormone (iPTH) levels measured on the first day after total thyroidectomy on prediction for permanent hypoparathyroidism.Methods:Totally 546 patients with thyroid cancer and benign thyroid lesions who underwent total thyroidectomy at Department of General Surgery, Beijing Chaoyang Hospital, Capital Medical University from February 2008 to December 2018 were analyzed retrospectively. There were 158 males and 388 females aging (50.9±13.2) years (range: 19.0 to 79.2 years). Serum calcium and iPTH levels were collected before surgery, on the first day and 6 months after surgery. Logistic regression was used to analyze the correlation between each data and the occurrence of permanent hypoparathyroidism after surgery.The area under the receiver operating characteristic curve was used to evaluate the predictive power of iPTH for postoperative occurrence of permanent hypoparathyroidism.Results:Among the 546 cases of total thyroidectomy, 22 cases of permanent hypoparathyroidism occurred, with an incidence of 4.0% (22/546). Multivariate analysis showed that iPTH levels on the first day after total thyroidectomy ( OR=2.932, 95 %CI: 1.129 to 7.616, P=0.027) and serum calcium levels ( OR=2.584, 95 %CI: 1.017 to 6.567, P=0.046) were independent prognosis factors for postoperative permanent hypoparathyroidism. When the threshold value of iPTH at 24 hours after total thyroidectomy was 5.51 ng/L, the AUC was 0.956 (95 %CI: 0.936 to 0.972, P=0.000), sensitivity was 100%, specificity was 85.1%, positive predictive value was 22%, negative predictive value was 100%. When the threshold value of serum calcium at 24 hours after total thyroidectomy was 1.93 mmol/L, the AUC was 0.733 (95 %CI: 0.694 to 0.770, P=0.000), sensitivity was 63.6%, specificity was 78.1%, positive predictive value of 10.8% and negative predictive value of 98.1%. Conclusions:Serum iPTH and calcium levels on the first day after total thyroidectomy were related to the occurrence of permanent hypoparathyroidism postoperatively. The predictive value of iPTH level is higher than that of serum calcium level.