Objective To construct a finite element analytical model of multiloop edgewise arch wire(MEAW),and study its mechanical characteristics.Methods Three-dimensional(3D) model of dentition-bracket-arch wire was set up in an initial graphics exchange specification(IGES) format complex by Pro/E software.The multiloop edgewise arch wire was spliced on the lower dentition.After dividing the arch wire and brackets with quarter-tetrahedron element method,the model was analyzed by ANSYS(an engineering simulation software).Results The finite element analytical model of multiloop edgewise arch wire was successfully built up.Based on the model,when multiloop edgewise arch wire was subjected to a heavy strength in certain parts(such as tooth 3,4),the anti-force strength on the other brackets(such as tooth 1,2,5,6,7) was not so heavy.The subjected strength was light and soft,especially on the first molar.Conclusion The results suggest that the finite element analytical model of multiloop edgewise arch wire built up in the experiment may be used to study the integrated mechanical characteristics,reveal the orthodontic specialty,and discuss the orthodontic mechanisms of multiloop edgewise arch wire techniques.

AIM: To observe the effects of ?-MSH on the expression of CD14 and TLR4 mRNA in mou se peritoneal macrophages induced by LPS and explore the mechanisms of ?-MSH ag ainst LPS. METHODS: BALB/C mouse peritoneal macrophages were cultured in the presence of LPS or LPS plus ?-MSH, and the expressions of CD14 and TLR4 mRNA were detected with the m ethod of reverse transcription polymerase chain reaction (RT-PCR). RESULTS: It was found that native murine macrophages o nly expressed a small amount of CD14 and TLR4 mRNA. Both CD14 and TLR4 mRNA expr ession to LPS in mouse macrophages increased significantly than those of contro l group at 6 h and maintained high level until 24 h when they reached to the pea k. Then the expression of CD14 mRNA backed to the normal gene expression baselin e, while TLR4 mRNA had excessive expression at 48 h. In presence of LPS and ?- MSH, the expression of CD14 and TLR4 mRNA decreased remarkably than those of L PS group (P0.05). Only when the dose s of ?-MSH attained to 1, 10 or 100 nmol/L,?-MSH could affect LPS-stimulated e xpression of CD14 and TLR4 mRNA (P0.05). CONCLUSION: These studies suggest that effects of ?-MSH against LPS are associated with its suppressing the critical receptor (CD14 and TLR4) expression of the LPS signal transduction and inhibiting the activation of macrophages.

Because of complexity and non-predictability of the tunnel surrounding rock, the problem with the determination of the physical and mechanical parameters of the surrounding rock has become a main obstacle to theoretical research and numerical analysis in tunnel engineering. During design, it is a frequent practice, therefore, to give recommended values by analog based on experience. It is a key point in current research to make use of the displacement back analytic method to comparatively accurately determine the parameters of the surrounding rock whereas artificial intelligence possesses an exceptionally strong capability of identifying, expressing and coping with such complex non-linear relatiouships. The parameters can be verified by searching the optimal network structure, using back analysis on measured data to search optimal parameters and performing direct computation of the obtained results. In the current paper, the direct analysis is performed with the biological emulation system and the software of Fast Lagrangian Analysis of Continua (FLAC3D. The high non-linearity, network reasoning and coupling ability of the neural network are employed. The output vector required of the training of the neural network is obtained with the numerical analysis software. And the overall space search is conducted by employing the Adaptive Immunity Algorithm. As a result, we are able to avoid the shortcoming that multiple parameters and optimized parameters are easy to fall into a local extremum. At the same time, the computing speed and efficiency are increased as well. Further, in the paper satisfactory conclusions are arrived at through the intelligent direct-back analysis on the monitored and measured data at the Erdaoya tunneling project. The results show that the physical and mechanical parameters obtained by the intelligent direct-back analysis proposed in the current paper have effectively improved the recommended values in the original prospecting data. This is of practical significance to the appraisal of stability and informatiomzation design of the surrounding rock.

Because of complexity and non-predictability of the tunnel surrounding rock, the problem with the determination of the physical and mechanical parameters of the surrounding rock has become a main obstacle to theoretical research and numerical analysis in tunnel engineering. During design, it is a frequent practice, therefore, to give recommended values by analog based on experience. It is a key point in current research to make use of the displacement back analytic method to comparatively accurately determine the parameters of the surrounding rock whereas artificial intelligence possesses an exceptionally strong capability of identifying, expressing and coping with such complex non-linear relatiouships. The parameters can be verified by searching the optimal network structure, using back analysis on measured data to search optimal parameters and performing direct computation of the obtained results. In the current paper, the direct analysis is performed with the biological emulation system and the software of Fast Lagrangian Analysis of Continua (FLAC3D. The high non-linearity, network reasoning and coupling ability of the neural network are employed. The output vector required of the training of the neural network is obtained with the numerical analysis software. And the overall space search is conducted by employing the Adaptive Immunity Algorithm. As a result, we are able to avoid the shortcoming that multiple parameters and optimized parameters are easy to fall into a local extremum. At the same time, the computing speed and efficiency are increased as well. Further, in the paper satisfactory conclusions are arrived at through the intelligent direct-back analysis on the monitored and measured data at the Erdaoya tunneling project. The results show that the physical and mechanical parameters obtained by the intelligent direct-back analysis proposed in the current paper have effectively improved the recommended values in the original prospecting data. This is of practical significance to the appraisal of stability and informatiomzation design of the surrounding rock.

Objective To prepare novel alkanethiol modified magnetic silver flower nanoparticles as SERS substrate to chloramphenicol for Raman detection and to determine their enhancement effect.Methods An alkanethiol was chosen as a surface modifier of the substrate and was self-assembled onto the magnetic silver flower nanoparticle surface.The chloram-phenicol molecules were enriched to the surface of the substrate by hydrophobic interaction and the effect for detection of chloramphenicol SERS signal was enhanced.Results It was found that the 1-hexanethiol-modified SERS substrate was able to lead to stronger enhancement than 1-dodecanethiol and octadecanethiol.Fe3 O4@SiO2-Ag-C6 was used to detect the chloramphenicol (10 -3 -10 -10 mol/L) and chloramphenicol in milk (10 -3 -10 -9 mol/L) by surface-enhanced Raman spectroscopy.The detection limits were 0.1 nmol/L (32 ppt) and 1 nmol/L (323 ppt) respectively.Conclusion Alkanethiol modified magnetic silver flower nanoparticles are a highly active SERS substrate, which can be used for detection of low concentrations of analytical substances.

A new medical research technology that combines surface enhanced Raman spectroscopy (SERS)with labeling immune technique is emerging with the development of SERS.This paper is intended to describe the principles, research progress and existing problems relating to SERS labeling immunoassay technology.We also summarize the research techniques for improving the sensitivity of SERS labeling immunoassay and the methods to eliminate nonspecific adsorption in SERS labeling immunoassay.Furthermore,the future development of SERS labeling immunoassay technology is discussed.

Objective To develop a new type of Raman-enhanced substrate for rapid detection of E.coli based on label-free surface-enhanced Raman scattering( SERS) technology.Methods Stober’ s improved method was used to prepare 360 nm silica ( SiO2 ) nanospheres.Prepared gold core-silver shell nanoparticles( Au@Ag) of different size were attached to 360 nm SiO2 to fabricate the nanocomposites ( SiO2-Au@Ag ) that were characterized by transmission electron microscopy (TEM) and UV-visucl light adsorption spectra (UV-Vis).PATP was detected to select SiO2-Au@Ag with optimal SERS effect.This optimal SiO2-Au@Ag was used to obtain the sensitivity of PATP and E.coli detection after a simple mixed culti-vation.Results TEM images showed that Au@Ag aggregated with the size of Au@Ag attached to 360 nm SiO2 .UV-Vis spectra indicated that the maximum absorption of Au@Ag and SiO2-Au@Ag had a red shift with the invrease of Au@Ag size.The experiment results suggested that detection sensitivity of PATP by SiO2-100 nm Au@Ag 10 -10 mol/L, while the lowest detectable E.coli concentration was 105 CFU/ml.Conclusion The 360 nm SiO2 binding with 100nm Au@Ag exhibits great potential for SERS applications.

Osteonecrosis is the most common disorder in femoral head and scaphoid. However, avascular necrosis (AVN) in metacarpal head is a rare disease. In the present study, a 14-year-old male patient complained of right-hand pain with a limited range of motion for one month. Physical examination showed that the active flexion was 70° and the extension was limited to 30° of the metacarpophalangeal (MCP) joints. The grip strength decreased to 60% of the contralateral hand. X-rays demonstrated flattening and sclerotic changes in the long finger and ring finger of metacarpal head. CT scanning indicated cystic, osteochondral defects and sclerotic changes in metacarpal head. Imaging examination further confirmed the diagnosis of AVN in the long metacarpal finger and ring finger. After conservative treatments including splint immobilization, non-steroidal anti-inflammatory drugs (NSAIDs) and physiotherapy, the local pain symptoms of the MCP joint gradually disappeared. The range of motion of MCP joint returned to normal with the grip strength score as 105% of the contralateral hand. MRI confirmed excellent remodeling and regeneration in the metacarpal head at two years later. The clinical characteristics, diagnosis and treatments of AVN of metacarpal head were reviewed. Although radiograph examination is commonly used, early-stage osteonecrosis of the metacarpal head should be confirmed by MRI. Given the rarity of this disorder, there is no consensus on the treatments. Metacarpal necrosis is the more common disorder in adolescent patients with a history of trauma. Considering the potential of bone remodeling, juveniles with metacarpal head necrosis could recover by conservative treatments.

Objective To evaluate the renal oxygenation in patients with primary nephrotic syndrome (PNS) using BOLD MRI.Methods Twenty patients with untreated first-onset PNS and 18 healthy control subjects underwent BOLD MRI.The R2* of renal cortex and medulla were measured.Blood and urine samples were obtained on the day of MRI,and the patients underwent renal biopsy after MRI.The renal tubulointerstitial damage scores (TIDS) were determined using Katafuchi criteria.All patients received corticosteroids within 7 days after MRI and were followed up for 12 months.The difference of R2* levels between the PNS patients and controls were compared,and the correlations between R2* values and TIDS,laboratory parameters (eGFR,etc.) were tested.Results R2* values of renal medulla in PNS patients significantly decreased compared that of the controls (t =-9.270,P＜0.001).R2* values of renal medulla in PNS patients were negatively correlated with eGFR (r=-0.462,P=0.040) and positively correlated with TIDS (r=0.809,P＜0.001).There was a slight tendency for higher R2* values of renal medulla in individuals with poor prognosis.Conclusion BOLD MRI is a noninvasive method for the detection of renal oxygenation changes,which can evaluate the renal function and tubulointerstitial impairment,as well as prediction of the prognosis for PNS patients.

Adolescent ; Adult ; Child ; Factor VIII ; genetics ; metabolism ; Hemophilia A ; blood ; diagnosis ; Humans ; Male ; Young Adult