The current treatment of medical implant-associated infections is still challenging.The infections are particularly persistent because the bacteria attaching to the implant surfaces produce a protective matrix which establishes itself as biofilms,shielding the bacteria from antibiotics.Biofilm bacteria are resistant to antimicrobics at levels 500 to 5,000 times higher than those needed to kill non-biofilm bacteria.In vitro experiments have shown that electric current has anti-infection effect and can enhance the activity of some antimicrobial agents against certain bacteria in the biofilms.Direct electrical stimulation has already been safely used in humans for fracture healing.In this article,we review the current state and development in research on the anti-infection effect of electrical stimulation.

BACKGROUND:Previous studies have found that endogenous gaseous signaling molecules such as NO, CO, H2S and SO2 play an important role in acute lung injury;there also have other gases participation, such as carbonyl sulfide.
OBJECTIVE:To investigate the effect of carbonyl sulfide for limb ischemia-reperfusion induced acute lung injury and its mechanism in rats.
METHODS:A total of 64 Sprague-Dawley rats were randomly divided into eight groups. Control group:without treatment;model group:limb ischemia for 4 hours and then reperfusion for 2 hours. Low-, moderate-and high-dose carbonyl sulfide groups were intraperitoneal y injected with 0.2, 0.5, 1.0 mL carbonyl sulfide respectively at 20 minutes before ischemia for 4 hours and reperfusion for 2 hours. Low-, moderate-and high-dose air groups were intraperitoneal y injected with 0.4, 1.0, 2.0 mL air respectively at 20 minutes before ischemia for 4 hours and reperfusion for 2 hours. 2 hours after reperfusion, the morphological changes of lung tissues and the change of lung coefficient were observed. The expressions of tumor necrosis factor-a, interleukin-1βand interleukin-6 both in lung tissue and serum were detected by enzyme linked immunosorbent assay. Cel apoptosis was measured by TUNEL assay.
RESULTS AND CONCLUSION:(1) Compared with the control group, significant damage of lung tissue was seen, and the lung coefficient increased significantly in the model group (P<0.05). The expressions of tumor necrosis factor-a, interleukin-l and interleukin-6 both in lung tissue and plasma increased (P<0.05), and apoptotic rate increased. (2) Compared with the model group, low-, moderate-and high-doses of carbonyl sulfide could mitigate the degree of lung injury, and reduce pulmonary coefficient and apoptotic rate. The low dose showed the most obvious effect. Low-and moderate-dose carbonyl sulfide could significantly decrease expressions of tumor necrosis factor-a, interleukin-1βand interleukin-6 both in lung tissue and plasma (P<0.05). (3) No significant difference in each index was visible in the low-, moderate-and high-dose air groups compared with the model group. (4) Results suggested that low dose of exogenous carbonyl sulfide through anti-inflammatory, anti-oxidant effects plays the protective role on limb ischemia/reperfusion-induced acute lung injury in rats.

Objective To determine the expressions of miR-200a, miR-141, miR-205 and miR-34a in epithelial ovarian cancer (EOC) samples and to explore their clinical significance. Methods According to FIGO staging, 44 EOC pa?tients were divided into two groups:early FIGO stage (stageⅠ-Ⅱ, n=15) and late FIGO stage (stageⅢ-Ⅳ, n=29). Expres?sions of 4 miRNAs were detected by real time quantitative PCR, and were compared between two groups. The correlation of 4 miRNAs was calculated. EOC patients were divided into high miRNA expression group and low expression group according to the median value of miRNAs expression. Kaplan-Meier survival analysis and Cox multivariate analysis were used to com?pare the age, FIGO state, tumor residual after operation and post-operative chemotherapy of ovarian cancer between two groups. Results The expression of miR-141 was elevated in stagesⅢandⅣcompared with that of stagesⅠand Ⅱ(P=0.036). There was a positive correlation between expression of miR-141, miR-200a and miR-205, but a negative correlation with miR-34a (P<0.05). There was a positive correlation between miR-200a and miR-205 (P<0.05). Lower miR-200a ex?pression was associated with shorter progress free survival in ovarian cancer analyzed by log-rank test ( P=0.035). The sur?vival rate was significantly higher in FIGO stages ⅠandⅡthan that of FIGO stagesⅢandⅣ(P<0.05). Cox regression analysis revealed that miR-200a, FIGO stage and age were influential factors of overall survival time and progress-free sur?vival time of ovarian cancer, while miR-141, miR-205, miR-34a and tumor residual after operation and post-operative che?motherapy were not influential factors. Conclusion The expression of miR-200a is closely correlated with the progress and prognosis of ovarian cancer and may be used as an independent indicator for ovarian cancer prognosis.

BACKGROUND:Some studies have shown that blocking the venous return can promote fracture healing but there is no study about the effect of repeated transient ischemia on promoting fracture healing. OBJECTIVE:To observe the promoting effect of repeated transient ischemia on early fracture healing based on micro-CT technique. METHODS: Forty-eight Wistar rats were used to make animal models of right tibial midpiece closed fractures folowed by K-wire fixation. Rats were randomly divided into four groups: 24-hour group, 48-hour group, 72-hour group and control group. Tourniquet was used on the root of the affected thigh, inflated for 10 minutes, and then released for 10 minutes. Three above-mentioned cycles were taken as an ischemic treatment. At 24 hours after fracture fixation, the ischemic treatment was first carried out, and after that, it was done every 24 hours in the 24-hour group, every 48 hours in the 48-hour group and every 72 hours in the 72-hour group. In the control group, the tourniquet with no inflation was used once on the right lower limb every 24 hours after fixation. Al the rats were kiled at 2 weeks after modeling to take out the right tibia with removal of K-wires for micro-CT observation. RESULTS AND CONCLUSION:The trabecular bone volume and total volume in the regions of interest were significantly higher in the 24-hour group than the other three groups (P < 0.05), but the tissue mineral density and calus tissue mineral density were significantly lower in the 24-hour group than the other three groups (P < 0.05).There was no significant statistical difference in the bone volume fraction among the four groups (P > 0.05). These findings indicate that within 2 weeks after fractures, the repeated transient ischemia can promote fracture healing, which may be related to the improvement in the secretion of growth factor, revascularization and osteoblast proliferation induced by repeated transient ischemia.

AIM:To investigate the role of PI3K/Akt and JAK2/STAT3 pathways in the protection of sulfur dioxide (SO2) against limb ischemia/reperfusion (I/R)-induced acute lung injury (ALI) in rats.METHODS:ALI was induced by limb I/R in the SD rats.Na2 SO3 (0.54 mmol/kg, ip)/NaHSO3 (0.18 mmol/kg, ip) as SO2 donor was injec-ted at 20 min before reperfusion.The inhibitors of JAK2/STAT3 and PI3K/Akt pathways, Stattic (3 mg/kg, iv) and LY294002 (40 mg/kg, iv), respectively, were injected at 1 h before reperfusion.Peripheral blood and lung tissues were collected for determining the contents of the cytokines, the protein levels of the molecules related to the signaling pathways, apoptosis and histopathologic changes by ELISA, TUNEL and Western blot.RESULTS:Compared with control group, the content of MDA, the activity of MPO, lung coefficient, apoptotic index, cytokine expression, and the protein levels of p-Akt and p-STAT3 in I/R group all increased significantly, and administration of Na2 SO3/NaHSO3 attenuated the damage in the lung.Besides, the results of Western blot showed that the rat lung tissues expressed p-STAT3 protein and p-Akt pro-tein.After I/R, the protein levels of p-STAT3 and p-Akt were increased.After using Na2 SO3/NaHSO3 , p-Akt was in-creased, but p-STAT3 was decreased (P<0.05).CONCLUSION:Both JAK2/STAT3 and PI3K/Akt pathways are like-ly involved in the protective effect of SO2 against limb I/R-induced ALI in rats.The activation of JAK2/STAT3 signaling pathway increases I/R injury.Reversely, the activation of PI3K/Akt signaling pathway reduces I/R injury.Besides, JAK2/STAT3 and PI3K/Akt signaling pathways may have crosstalk during I/R-induced ALI and JAK2/STAT3 pathway may have an impact on the P13K/Akt pathway.

Objective To investigate the expression and clinical significance of Smac and HtrA2 in children with acute leukemia(AL).Methods Bone marrow samples were obtained from 77 children with AL (including 32 newly diagnosed children,33 complete remission children and 12 relapsed children)and the control group of 15 children without malignant blood disease.The expressions of Smac and HtrA2 protein were measured by streptavidin/peroxidase immunoperoxidase technique(SP) in all children.SPSS 13.0 software was applied to analyze the statistical data.Results Protein Smac was detected only in some samples,but HtrA2 was detected in all samples.The levels of Smac and HtrA2 protein in newly diagnosed AL children were both higher than those of the complete remission children (x2 =17.38,F =2.36,all P ＜ 0.05) and normal controls (x2 =12.89,F =5.26,all P ＜ 0.05),there was a statistical significance,but compared with those in the relapsed children,the difference had no statistical significance (x2 =1.18,F =1.57,all P ＞ 0.05).The levels of Smac and HtrA2 protein in complete remission children were both higher than those of the normal controls,and the difference had no statistical sigmficance(x2 =1.20,F =2.23,all P ＞ 0.05).In the newly diagnosed children,the levels of Smac and HtrA2 protein in children with acute lymphocytic leukemia(ALL) were higher than those of the acute myeloid leukemia(AML),but the differences had no statistical significance(x2 =0.113,t =1.024,all P ＞ 0.05).In newly diagnosed AL children,the complete remission(CR) rate of the negative expression of Smac(Smac-,90.9％) and the low expression of HtrA2(HtrA2low,84.6％) in the level of protein were higher than those of the positive expression of Smac(Smac +,47.6％) and the high expression of HtrA2 (HtrA2high,47.4％),and there was statistical significance respectively(x2 =5.772,4.596,all P ＜ 0.05).The CR rate of Smac-HtrA2low group (100％) was higher than that of Smac+ HtrA2high group(30.8％)in the children with AL,and the statistical data were of great significance(x =9.692,P ＜0.01).The protein level of Smac in newly diagnosed AL children was correlatedwith HtrA2 (r =0.979,P ＜ 0.001).Conclusions Pro-apoptotic protein Smac and HtrA2 may be involved in and af-fected each other in the pathogenesis and progression in AL,but levels of Smac and HtrA2 protein may be not correlatedwith the types of AL.In newly diagnosed AL children,the high expression of protein Smac and HtrA2 predicts poorprognosis.

Objective To explore the influence of brief ischemic on fracture healing.Methods Two hundred and forty wistar rats (weight was 200 g and half male) were made the right tibial midpiece closed fracture model.1.0 mm K-wires were used to fix the fractures.Rats were divided into 4 groups.Group A was 24 hours,group B was 48 hours,group C was 72 hours,and group D was the control group.Tourniquet was used on the root of the thigh of right lower limb.Tourniquet was inflated 10 min,then released 10 min,and repeated 3 times to make the brief ischemic model.48 rats were made brief ischemic at 24 hours after the fracture fixed.Then group A was at every 24 hours,group B was at every 48 hours,and group C was at every 72 hours made brief ischemic.Group D at every 24 hours after the fracture fixed was used tourniquet on the root of thigh of right lower limb each time 1 hour,but the tourniquet was not inflated.Group A,B,and C were made brief ischemic 5 weeks.Group D was tourniquet treated 5 weeks.Group A and D at 1 day,3 days,5 days,and 7 days after fracture fixed were detected the serum VEGF.All groups of rats were X-ray examinated and detected of serum VEGF at every two weeks after the fracture fixed.Every two weeks,every group randomly selected 12 rats to do immunohistochemical staining.We used the Image Pro Plus software to quantitative compare the IGF-2 positive cells in the fracture area.Results X-ray results were used three points method for analyzing.The scores of group A,B,and C were significantly higher than group D at 2 weeks,4 weeks,6 weeks after fracture fixed (P ＜ 0.05).The scores between group A,B,and C were no significant statistical difference at 2 weeks,4 weeks,6 weeks after fracture fixed (P ＞ 0.05).The levels of serum VEGF of group A were significantly higher than group D at 3days,5days,and 7 days after fracture fixed (P ＜ 0.05).The levels of serum VEGF of group B and C were obviously higher than group A and D at 2 weeks (P ＜ 0.05),and there was no obvious difference between group B and C (P =0.79,P =0.90,P =0.88).The same result was found between group A and D (P =0.94,P =0.551,P =0.53).There were no significant difference between four groups on the levels of serum VEGF at 8 weeks (P =0.66).Immunohistochemical results were that group B,group C VEGF positive cells were significantly higher than group A and group D at 2 weeks,4 weeks,6 weeks (P ＜0.05).There was no significant difference in group B and group C (P =0.19,P =0.10,P =0.38),or group A and group D (P =0.07,P =0.17,P =0.18).There was no significantly different in four groups at 8 weeks (P =0.08).Conclusions Brief ischemic can promote the healing of fracture and stimulate the expression of VEGF.The mechanism may be related to the signal channels of VEGF and other biological factors.This study will give new idea to clinic for promoting fracture healing.

Objective To verify the reliability of novel 3D classification of intertrochanteric fractures by comparing the consistency between conventional and novel classifications.Methods Included for the present study were the preoperative X-ray and CT images of 189 patients with intertrochanteric fracture who had been hospitalized at Department of Orthopaedics,Beijing Chao Yang Hospital,Capital Medical University from 1 January,2017 to 1 January,2019.The patients' intertrochanteric fractures were classified by 6 orthopedic surgeons independently using Evans classification,Jensen classification,AO classification and novel 3D classification,respectively.One month later,the original images of the 189 patients were renumbered and classified again in the same way.The Kappa values between observers and within observers were calculated for the classifications of intertrochanteric fractures based on X-ray and CT images.Results In Evans classification,Jensen classification,AO classification and novel 3D classification,the interobserver Kappa values of X-ray films were 0.54 ± 0.03,0.53 ± 0.03,0.45 ± 0.03 and 0.63 ± 0.02,respectively,and the interobserver Kappa values of the CT images were 0.49 ± 0.03,0.49 ± 0.03,0.44 ± 0.04 and 0.63 ± 0.03.The intraobserver Kappa values of the X-ray films were 0.53 ± 0.02,0.54 ± 0.03,0.44 ±0.04 and 0.65 ± 0.02,respectively,and the intraobserver Kappa values of the CT images were 0.52 ± 0.03,0.52 ±0.03,0.41 ±0.02 and 0.64 ±0.03.In the novel classification based on X-ray and CT images,the interobserver and intraobserver Kappa values were both significantly higher than those in Evans,Jensen and AO classifications (P ＜ 0.05).Conclusion The novel 3D classification of intertrochanteric fractures is more reliable than the conventional ones.

Heart sound is one of the common medical signals for diagnosing cardiovascular diseases. This paper studies the binary classification between normal or abnormal heart sounds, and proposes a heart sound classification algorithm based on the joint decision of extreme gradient boosting (XGBoost) and deep neural network, achieving a further improvement in feature extraction and model accuracy. First, the preprocessed heart sound recordings are segmented into four status, and five categories of features are extracted from the signals based on segmentation. The first four categories of features are sieved through recursive feature elimination, which is used as the input of the XGBoost classifier. The last category is the Mel-frequency cepstral coefficient (MFCC), which is used as the input of long short-term memory network (LSTM). Considering the imbalance of the data set, these two classifiers are both improved with weights. Finally, the heterogeneous integrated decision method is adopted to obtain the prediction. The algorithm was applied to the open heart sound database of the PhysioNet Computing in Cardiology(CINC) Challenge in 2016 on the PhysioNet website, to test the sensitivity, specificity, modified accuracy and F score. The results were 93%, 89.4%, 91.2% and 91.3% respectively. Compared with the results of machine learning, convolutional neural networks (CNN) and other methods used by other researchers, the accuracy and sensibility have been obviously improved, which proves that the method in this paper could effectively improve the accuracy of heart sound signal classification, and has great potential in the clinical auxiliary diagnosis application of some cardiovascular diseases.
Algorithms ; Databases, Factual ; Heart Sounds ; Neural Networks, Computer