BACKGROUND: The most commonly used rod-screw posterior spinal fixation system has some biomechanical drawbacks. The screw-plate system is more preferred for patients.OBJECTIVE: To prepare a new posterior spinal fixation system based on imaging results of distance between two pedicles,radian of spine flexion, extension and the height of intervertebral space of Chinese population.METHODS: The thoracolumbar data of 129 normal people were measured. According to the imaging measurements and relative documents, a device of gear-distraction plate (GDP) for spine reduction and fixation was designed. Eighteen fresh calf lumbar specimens were randomly divided into 3 groups, the test group was fixed by GDP and the other groups were fixed by CD and Steffee plate, respectively. The results of the displacement, strain, strength, stiffness and ultimate strength were measured under the states of vertical compression, flexion, extension and lateral bending respectively, and the results were statistically analyzed.RESULTS AND CONCLUSION: GDP could meet the need of strength and stiffness of human bodies. It showed superior to the CD and Steffee plate groups in strength and stiffness (P ＜ 0.05), with 13% or 14% torsion intensity greater than that of the CD or Steffee plate groups. The ultimate mechanical performance test showed that, the load bearing of the GDP group was greater than that of the CD and Steffee plate groups (P ＜ 0.05). The findings demonstrated that GDP for Chinese human presented with good biomechanical stability, which can promote vertebrae fracture union and prevent kyphosis relapses or vertebral height loses.

AIM: To determine the effect of heat treatment on rat primary cultured neurons, and give fundamental research for candidate molecule to protect the neurons from heat injury. METHODS: Neurons from rat striatum were primary cultivated in D-MEM with 15% horse serum, and when got mature, cells were identified by immuno-cytochemical staining with neurofilament protein (NF), tyrosine hydroxylase (TH) and neuron specific enolase (NSE) antibodies. Cells in heat treatment groups were put in an 43 ℃ CO 2 incubator for 1 h, and the control groups at 37 ℃ as normal. Striatum neurons were stained with trypan blue and dual fluorscence dye (PI/H33258) immediately followed heat treatment, and necrosis rate of neurons was estimated. At the same time, activated caspase-3 immuno-cytochemical and TdT TUNEL methods were applied to determine apoptosis rate, and cell volume was also identified with micro-photography. RESULTS: During day 7 to day 9, the cultured striatum neurons got mature, and many neuronal fibers starched out and formed neuron network, NF, TH, and NSE staining positive. Treatment at 43 ℃ for 1 h, cell number decreased greatly, while NF+ percentage kept unchanged, and the heat treatment survived neurons were processing cell necrosis and apoptosis, but necrosis percentage was much greater than that of apoptosis. While cell volume kept unchanged after heat treatment. CONCLUSION: Heat treatment greatly affects the growth and survival of the cultured striatum neurons, and the injury effect is most due to cell necrosis process.

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.

ObjectiveTo clarify the characteristics and clinical signiifcance of the NOTCH1 mutations in childhood T-cell acute lymphoblastic leukemia (T-ALL).MethodsAmplify and sequence the heterodimerization (HD) domain and the pro-line-glutamicacid-serine-threonine (PEST) domain of theNOTCH1 gene in 28 T-ALL children, in order to explore the frequency, position and type of the mutations as well as their reletions with prognosis.ResultsIn 28 children with T-ALL, 15 cases (51.57%) had been identiifed theNOTCH1 mutations, all of which were heterozygous mutations. The lymphoblast counts in peripher-al blood and bone marrow in theNOTCH1 mutant group at admission were signiifcantly higher than in the non-mutant group (P<0.05). The 1-year remission rate in the 28 children with T-ALL was 75% (21/28), including 80% (12/15) in mutant group in which 3 patients relapsed and all of them died (1-year mortality 20%) and 69.20% (9/13) in non-mutant group in which 4 patients relapsed but all survived (1-year mortality 0%).ConclusionsThe children with T-ALL had a high incidence of NOTCH1 mu-tations at various sites. In addition, the patients withNOTCH1 mutations had more severe disease at diagnosis, better short-term prognosis and poor outcome with salvage therapy after relapse.

Objectives To investigate the correlation between single nucleotide polymorphisms (SNP) in interleu-kin-15 (IL-15) and treatment response in childhood acute lymphoblastic leukemia (ALL). Methods Genomic DNA samples extracted from remission bone marrow cells of ALL patients were genotyped by MassArray. Five SNPs (rs10519612, rs10519613, rs17007695, rs17015014 and rs35964658) in IL-15 and their association to minimal residual disease (MRD) status in the end of induction therapy were studied. Results SNP rs17007695 was associated with the early response in children with ALL(P=0.049) and the incidence of positive MRD after induction therapy in CC genotype carriers was 1.8 times more than that in TT genotype carriers. Haplotype analysis of these five SNPs showed that the frequency of haplotype CACGG in MRD positive group was 2.1 times higher than that in MRD negative group (P=0.035). Conclusions IL-15 gene polymorphism was associated with the early treatment response in Han Chinese children with acute lymphoblastic leuke-mia.

Objective To evaluate the clinical curative effect of ulinastatin combined with CRRT in the treatment of multiple organ dysfunction syndrome(MODS).Methods Sixty eight patients with MODS who were admitted to ICU from July 2013 to July 2015 were randomly divided into three groups:control group,CRRT group,combined group;Patients' APACHE Ⅱ,SOFA scores level of inflammatory markers were recorded before treatment and after treatment of 72 hours and 7 days.The mortality of the three groups in ICU were compared.Results After 72 hours and a week of treatment,the level of IL-10,IL-6,TNF-α,WBC、PCT、CRP in CRRT group and combined group were significantly better than that of control group(P＜0.05),and combined group were significantly better than that of CRRT group.Compared with the control group,the oxygen index,lactic acid,ALT significantly im proved in CRRT group and combined group were better than control group,after 72 hours and a week of treatment(P＜0.05),and the cornbined group was the most obvious.After a week of treatment,the mortality rate of CRRT group and combined group was significantly better than the control group (P＜0.05),while there was no statistical differences between CRRT group and combined group(P＞0.05).Conclusion Ulinastatin combined with CRRT is an effective method for the treatment of MODS.

Objective:To compare the in vitro susceptibility of fluconazole-resistant Candida albicans strains from superficial and deep infections to 8 antifungal drugs, and to compare drug resistance mutations in these strains. Methods:According to the Clinical and Laboratory Standards Institute (CLSI) protocol M27-A4, 26 deep infection-derived and 33 superficial infection-derived drug-resistant Candida albicans strains were tested for in vitro susceptibility to 8 antifungal drugs (fluconazole, voriconazole, itraconazole, posaconazole, amphotericin B, fluorocytosine, terbinafine, and micafungin) alone or in combination. DNA was extracted from all drug-resistant strains, and mutations in 3 drug resistance genes, including ERG3, ERG11 and FUR1, were detected by PCR. Normally distributed measurement data with homogeneous variance were compared between two groups by using two-independent-sample t test, non-normally distributed measurement data with non-homogeneous variance were compared using Mann-Whitney U test, and enumeration data were compared using chi-square test. Results:The minimum inhibitory concentrations (MICs) of fluconazole, itraconazole, voriconazole, posaconazole and fluorocytosine all significantly differed between the superficial infection group and deep infection group (all P < 0.05) , while there was no significant difference in the MIC of amphotericin B or micafungin between the two groups (both P > 0.05) . The MIC of terbinafine was >64 μg/ml in 96.6% of the above strains, so could not be compared between groups. As combination drug susceptibility testing revealed, the combination of terbinafine with azoles (fluconazole, voriconazole, itraconazole or posaconazole) showed synergistic inhibitory effects against 15 Candida albicans strains (7 strains from deep infections, 8 strains from superficial infections) , with fractional inhibitory concentration (FIC) indices being 0.033 to 0.187; no marked synergistic effect was observed in the combinations between fluorocytosine and azoles, between fluorocytosine and amphotericin B, or between amphotericin B and fluconazole, with the FIC indices being 0.56 to 1.125. The missense mutation V351A in the ERG3 gene was identified in all the 33 (100%) superficial infection-derived strains, as well as in 13 (50%) deep infection-derived strains, and the mutation A353T in the ERG3 gene was identified in 4 (15%) deep infection-derived strains; as for the ERG11 gene, missense mutations identified in the superficial infection-derived strains included I437V (32 strains, 97%) , Y132H (23 strains, 70%) , T123I (16 strains, 48%) , K128T (6 strains, 18%) , D116E (5 strains, 15%) , A114S (4 strains, 12%) , E266D (2 strains, 6%) , G448E (2 strains, 6%) , and G465S (2 strains, 6%) , while missense mutations identified in the deep infection-derived strains included I437V (23 strains, 88%) , E266D (13 strains, 50%) , E260G (5 strains, 19%) , and V488I (4 strains, 15%) ; the missense mutation R101C in the FUR1 gene was identified in 11 (33%) superficial infection-derived strains, but not identified in deep infection-derived strains. Conclusion:The drug susceptibility and drug resistance mutations differed to some extent between superficial infection- and deep infection-derived fluconazole-resistant Candida albicans strains.

Objective To evaluate the effect of the treatment with low-concentration hydrogen peroxide (H2O2) on the adhesive function of and autophagy in human melanocytes,and to screen long noncoding RNAs (lncRNAs) related to autophagy.Methods Melanocytes were isolated from foreskins of healthy males after circumcision,and subjected to cultivation.Melanocytes at exponential growth phase were divided into 3 groups:control group receiving no treatment,H2O2 group treated with 400 μ mol/L H2O2,and H2O2 + NAC group pretreated with 4 mmol/L NAC for 2 hours followed by the treatment with 400 μmol/L H2O2.After 5-day treatment,immunofluorescence study was performed to determine the expression of Ecadherin,microtubule-associated protein 1 light chain 3 (LC3)and p62,and Western blot analysis to determine the expression of autophagy-related protein LC3 and p62.Cell structures and autophagosomes were observed by transmission electron microscopy,and autophagy-related lncRNAs were screened using gene chip technology.Statistical analysis was done with Graphpad Prism 6 software using one-way analysis of variance for comparison among groups,and Tukey's test for multiple comparisons.Results Under the confocal microscopy,the H2O2 group showed significantly decreased fluorescence intensity of E-cadherin and LC3 in the melanocytes and decreased number of autophagosomes in melanocytes,but significantly increased fluorescence intensity of p62 compared with the control group and H2O2 + NAC group.Western blot analysis showed that the LC3-Ⅱ/LC3-Ⅰ ratio in the melanocytes was significantly lower in the H2O2 group (0.604 ± 0.012) than in the control group (1.200 ± 0.081,q =7.718,P ＜ 0.01) and H2O2 + NAC group (1.017 ± 0.062,q =5.076,P ＜ 0.05),while the p62/β-actin ratio in the melanocytes was significantly higher in the H2O2 group (0.881 ± 0.079) than in the control group (0.456 ± 0.121,q =4.847,P ＜ 0.05) and H2O2 + NAC group (0.492 ± 0.049,q =4.439,P ＜ 0.05).There were no significant differences in the LC3-Ⅱ/LC3-Ⅰ ratio or p62/β-actin ratio between the H2O2 + NAC group and control group (P ＞ 0.05).Gene chip technology showed that 18 autophagy-related lncRNAs were associated with premature senescence of melanocytes and differentially expressed in the H2O2 group compared with the control group,and the autophagy-related lncRNA NONHSAT190308.1 (＞ 10-fold increase) was screened out.Conclusion Lowconcentration H2O2 can decrease the expression of E-cadherin and the level of autophagy in melanocytes,and can up-regulate the expression of autophagy-associated lncRNA NONHSAT190308.1.

Objective:To observe the impacts of different postures on the hemodynamics of lower extremity vein.Methods:In this single center non-randomized controlled study in 15 healthy female volunteers, the hemodynamic changes in the common femoral vein were detected by color Doppler ultrasound at 10 different postures: supine position, slope positions with bed end elevated at 15°, 30° and 45°, trapezoidal positions with bed end elevated at 15°, 30° and 45°, and positions with bed head elevated at 30°, 45° and 60°.Results:Different postures resulted in significant differences in the velocity of blood flow in the common femoral vein ( P<0.05), with slope position at 45°> slope position at 30°> slope position at 15° = trapezoidal position at 30°> trapezoidal position at 15° = trapezoidal position at 45°> supine position> position with bed head elevated at 30°> position with bed head elevated at 45° = position with bed head elevated at 60°. Conclusions:In the postures observed in this study, the slope position with bed end elevated at 45° can promote the most effectively the blood reflux in the lower extremity vein, the trapezoidal positions with bed end elevated may not facilitate the distal blood reflux in the lower extremity vein, and positions with bed head elevated may hinder the blood reflux in the lower extremity vein.

Objective:To investigate the epidemiological characteristics of lower extremity deep vein thrombosis (DVT) in patients with femoral fracture.Methods:Retrospectively analyzed were the data of 2,571 patients with femoral fracture who had been treated at the Third Hospital of Hebei Medical University from January 2019 to December 2019. There were 1,079 males and 1,492 females, aged from 14 to 96 years (average, 67.1 years). There were 1,158 femoral neck fractures, 951 femoral intertrochanteric fractures, 309 femoral shaft fractures, and 153 femoral condylar fractures. 2,414 patients were treated surgically while 157 patients non-surgically. Color Doppler ultrasonography of both lower extremities was performed to determine the occurrence of DVT before operation and every week after operation for patients undergoing surgical treatment, and within 48 hours after admission and every week during hospitalization for those undergoing non-surgical treatment. The incidence and location of DVT were recorded for different femoral fractures.Results:The incidence of DVT in this cohort was 35.5%(913/2,517), that of proximal DVT 5.3%(135/2,571), and that of distal DVT 30.3% (778/2,571). In patients with femoral neck fracture, femoral intertrochanteric fracture, femoral shaft fracture and femoral condylar fracture, the incidence of DVT was respectively 28.8% (334/1,158), 44.7% (425/951), 30.7% (95/309) and 38.6% (59/153), the incidence of proximal DVT was respectively 2.7% (31/1,158), 5.6%(53/951), 9.7% (30/309) and 13.7% (21/153), and the incidence of distal DVT was respectively 26.2% (303/1,158), 39.1% (372/951), 21.0% (65/309) and 24.8%(38/153). The incidence of DVT in the femoral vein and above, popliteal vein, tibiofibular vein and intermuscular vein in this cohort was respectively 2.3%(60/2,571), 2.9%(75/2,571), 6.4%(165/2,571) and 23.8%(613/2,571).Conclusions:The incidence of DVT may be high in patients with femoral fracture, and the proximal DVT with a high risk of pulmonary embolism may occur more in patients with femoral condylar fracture.