Objective To study the interaction between Cr(Ⅵ)-GSH complex and DNA and to understand the mechanism of DNA conformation change induced by Cr(Ⅵ)-GSH complex. Methods Chromium(Ⅵ) reacts on glutathione forms the chromium (Ⅴ) intermediate complex, and the intermediate complex can induce the conformation change of DNA, in the present paper, ultraviolet and fluorescence spectra, Scatchard equation, fluorescence quenching curve, and fluorescence probe method using ethidium bromide (EB) as a fluorescence probe were employed. Results The chromium (Ⅴ) intermediate complex formed rapidly after the reaction between Cr(Ⅵ) and GSH in Hepes buffer solution at pH=7.4, the complex did not insert into the base pairs on the DNA duplex strand and developed electrostatic binding with the phosphate backbone of DNA, but induced a conformation change of DNA leading to a disruption of duplex structure. In the following time, the complex decomposed and the end product was Cr(Ⅲ), Cr(Ⅲ) can cross-link with DNA, the whole process needs about an hour. Conclusion The chromium(Ⅴ) intermediate complex of the conformation change reaction of chromium(Ⅵ) and glutathione may play an important role in inducing the DNA.

Gold nanorods is a capsule-shaped gold nanoparticles. Gold nanorods give rise to two absorption peaks corresponding to their plasmonic modes, transverse mode and longitudinal mode, corresponding to light absorption and scattering along the short and long axis, respectively. The longitudinal surface plasmon resonance can be tuned by adjusting their aspect ratio from the visible to the NIR region and extremely sensitive to changes in the dielectric properties of the surroundings including solvents, adsorbates, and the interparticle distance of the gold nanorods. This unique optical property of gold nanorods opens up fascinating applications in biological and chemical sensors. Optical properties and biomedical application of gold nanorods are introduced, and its future research prospects are discussed.

Objective To study the effects of surfactants on conformation of hemoglobin and further to understand the potential impact of surfactants in environment on human health. Methods The changes of the conformation of hemoglobin induced by cation and anion surfactants were investigated with four methods, such as synchronous fluorescence spectra, UV, electrochemistry and atom force microscope. Results The changes of the conformation of hemoglobin induced by anion surfactant were obvious but were not by cation surfactant. Conclusion Sodium lauryl sulphate, an anion surfactant, may change the conformation of hemoglobin.

Objective To analyze the incidence of retinopathy of prematurity(ROP)among extreme-ly preterm infants,and to evaluate the treatment methods and effects among those with severe ROP.Methods A retrospective analysis was performed to analyze incidence of ROP in 96 cases of extremely preterm infants who were born at a gestational age of 〈28 weeks and survived beyond a postmenstrual age of at least 1 year from Apr 2006 to Oct 2013,and to analyze the treatment outcomes of photocoagulation and ranibizum-ab intravitreal injection among the infants with severe ROP.Results Fifty-six of 96 cases(58.33%)grew into ROP finally and 21 cases(21.88%)grew into severe ROP,2 cases(2.08%)grew into aggressive poste-rior ROP.Fifteen cases with severe ROP were treated with laser photocoagulation.Four cases with severe ROP were received ranibizumab intravitreal injection prior to photocoagulation.Two cases with severe ROP were only treated with ranibizumab intravitreal injection.The eyesight of 96 patients (100%)in this study were all preserved.Conclusion ROP screening should focus on extremely preterm infants because of higher incidence of ROP and severe ROP among them.The infants with severe ROP should be treated with laser photocoagulation in time.The infants in critical condition or with aggressive posterior ROP can be treated with ranibizumab injection.

BACKGROUND:The molecular mechanism of periprosthesis osteolysis is not yet completely clear. Periprosthetic osteolysis and absorption is the pathological and physiological process typical of artificial joint loosening. Interleukin-1 can affect bone resorption process through a mitogen-activated protein kinases (MAPK) signaling pathway.
OBJECTIVE:To explore the effects of siRNA-induced interleukin-1 receptor-associated kinase-4 gene (IRAK-4) silence on MAPK expression in MG63 cells, which may provide experimental basis for treatment and prevention of periprosthesis osteolysis.
METHODS:The siRNA sequences of the target gene, IRAK-4, were constructed and transferred into MG63 cells using Lipofectamine 2000. There were three groups:blank group=MG63 cells, control group=MG63 cells transfected with scrambled IRAK-4siRNA, and silence group=MG63 cells transfected with specific IRAK-4 siRNA. The protein level of extracellular regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinases (p38MAPK) were detected by western blot assay.
RESULTS AND CONCLUSION:The expression of IRAK-4 mRNA and protein in the silence group was significantly decreased compared with the control group. Compared with the blank and control groups, 48 hours after the transfection, IRAK-4 gene silencing in MG63 cells decreased protein expression of p-JNK1/2P46, p-ERK1/2 and p-p38MAPK (P<0.05). IRAK-4 silencing inhibited ERK, JNK and p38MAPK expression in osteoblast-like cells.

BACKGROUND: Acetabular cup orientation using a standard radiograph of the pelvis is quite common method to assess artificial hip replacement nowadays. Non-standardization of pelvic orientation affected accuracy of measurement results, and it is difficult to compare. OBJECTIVE: To make sure how pelvis tilting affect the anteveration of the cup and to elevate clinical accuracy and compare study comparability. METHODS: Designed a simulated acetabular cup with serial concentric circles which pass through the same polars and represent anteveration of 0°, 10°, 20°, 30°, 40°, Loaded the simulated acetabular cup at an inclination of 35°, 40°, 45°, 50°, 55° to6 cadaver pelves, Made the pelves tilt around the frontal axis and sagittal axis with 5° each time in a scope of+30°. Takestandard radiograph of the pelvis accordingly. Radiograph was photographed end frontal angle of dip was measured. RESULTS AND CONCLUSION: Pelvic tilt of about 1° causes measuring errors of anteveration 0. 61 °-0. 73°. The anteveration decreased at both acetabular cups when pelvic posterior tilt and at the acetabular cup that near the X-ray source as pelvic lateral tilt. The anteveration rose at both acetabular cups when pelvic anterior tilt and at the acetabular cup that away from the X-ray source as pelvic lateral tilt. During clinical evaluation, pelvic orientation effects on measurement results should be considered.

Objective To introduce a self-developed computer-assisted design/rapid prototyping and guidance system used for precise placement of the acetabular component in total hip arthroplasty.Methods We collected the preoperative pelvic CT scanning data of 10 hips with aeetabular dysplasia that had undergone primary total hip arthroplasty from January 2016 to January 2017.The total time for import of radiographic images,model reconstruction,model segmentation,acetabular component position design and STL model export was calculated and compared between our self-designed software and Mimics vl 7.0.Three kinds of STL model from each case were imported into our self-developed 3D printing device,Stratasys Objet30 and Stratasys Demension SST1200es respectively for rapid prototyping.The printing efficiency and accuracy were compared among the 3 printers.The accuracy of placing acetabular component with guidance system was evaluated.Results The average time forpreoperative planningwas7.7±1.3 minbyourself-designedsoftware and 52.5 ± 15.9 min by Mimics v17.0,showing a significant difference (P ＜ 0.001).In morphological point-based comparison for each case,the 3D models exported by the 2 different kinds of software showed an average difference of 0.072 1 ± 0.069 1 mm.The average durations for rapid prototyping by the 3 different printers were 5.3 ± 0.6 h,10.8 ± 0.5 h,and 9.3 ± 0.6 h,respectively,showing significant differences (P ＜ 0.001).The guidance system resulted in precise placement.The locations of the acetabular component achieved by guide-assisted placement were not significantly different from the target ones (P ＞ 0.05).Conelusion Our self-developed preoperative planning software,rapid prototyping device and guidance apparatus for acetabular component placement may lead to good accuracy and high efficiency.

Gingival recession could result in root exposure, dental hypersensitivity and poor aesthetics. It has been demonstrated that varieties of root coverage procedures can significantly improve gingival recession in short-term (≤6 months), of which coronally advanced flap combined with connective tissue graft is the gold standard technique for treatment of gingival recession. It could obtain the optimally complete root coverage and maintain long-term stability (≥2 years). However, clinical knowledge about the long-term effectiveness of the other alternative graft materials remain very limited. Based on the existing clinical evidence, this article reviews coronally advanced flap, coronally advanced flap combined with connective tissue graft or alternative graft materials, with particular attention to the long-term stability of them, in order to provide reference for the design of further clinical trials and the plan of clinical treatments.

OBJECTIVETo generate mice which are specific for peroxisomproliferator-activated receptor-γ coactivator-1(PGC-1α) knockout in the GABAergic interneuron.

METHODSConditional mice specific for PGC-1αwere introduced from the Jackson Laboratory, USA and initially inbred to obtain homozygote PGC-1αmice. The PGC-1αconditional mice were further crossed with Dlx5/6-Cre-IRES-EGFP transgenic mice to achieve specific knockout of PGC-1α in the GABAergic interneuron.

RESULTSThe offspring with specific knockout PGC-1α gene were successful for the generation of GABAergic interneuron, with the resulting genotype being PGC-1α.

CONCLUSIONThe PGC-1αmice were obtained through a proper crossing strategy, which has provided a suitable platform for studying the function of PGC-1α in neuropsychiatric diseases.

Animals ; Female ; Humans ; Interneurons ; metabolism ; Male ; Mice ; Mice, Knockout ; Neurodegenerative Diseases ; genetics ; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha ; genetics ; gamma-Aminobutyric Acid ; metabolism