Reconstruction of the Medial Patellofemoral Ligament Using Hamstring Tendon Graft With Different Methods： a Biomechanical Study

Objective To measure the tensile strength of the normal medial patellofemoral ligament （MPFL）, and evaluate the biomechanics of different fixation methods of the hamstring tendon graft on the patella. Methods Eight fresh cadaver knees were prepared by isolating the patella, leaving only the MPFL as its attachment to the medial condyle of femur, The MPFL was reconstructed by three different methods： four-suture fixation, anchors-single suture fixation, and anchors-double suture fixation. The tensile strength and the elongation of the normal MPFL and the tendon grafts were measured. Results The tensile strength of the four-suture fixation group （234.86±49.02 N） was stronger than that of the normal MPFL （146.91 ±25.30 N, P=0.0014） and the anchors-single suture group （159.17±49.07 N, P=0.0077）, while weaker than that of the anchors-double suture group （314.74±78.46 N, P=0.0052） Conclusions With regard to the tensile strength, the four-suture fixation method is reliable for clinical use. Compared with the anchor-suture method, the four-suture fixation method which has no specific implants is more economical, convenient and efficient.     

Expression of NYD-SP6 gene in testicles of azoospermia patients and normal men with different ages

Objective To study the expression of NYD SP6 gene in testes of azoospermia patients and normal men with different ages and the implication. Methods The testicular specimens at different ages were divided into three groups： fatal group （ n = 4 ）, adult group （ n = 4） and old men group （ n = 4）. The patients with azoosperrnia were divided into three groups： hypospermatogenesis group （ n = 7）, spermatogenic arrest group （ n = 13） and sertoli-cell-only （SCO） ） syndrome group （ n = 3 ）. The expression level of NYD-SP6 gene was detected by realtime PCR. Results Compared with adult group, the expression level of NYD-SP6 gene was decreased significantly in fatal and old men group, spermatogenic arrest group and SCD syndrome group （ P 〈 0.01 ）,     

Virus profile in children with acute respiratory infections with various severities in Beijing, China

Background Acute respiratory infection （ARI） is one of the most common infectious diseases in infants and young children globally.This study aimed to determine the virus profile in children with ARI presenting with different severities.Methods Clinical specimens collected from children with ARI in Beijing from September 2010 to March 2011 were investigated for 18 respiratory viruses using an xTAG Respiratory Viral Panel Fast （RVP Fast） assay.The Pearson chisquare analysis was used to identify statistical significance.Results Of 270 cases from three groups of ARI patients,including Out-patients,In-patients and patients in the intensive care unit （ICU）,viruses were detected in 176 （65.2％） specimens with the RVP Fast assay.The viral detection rate from the Out-patients group （50.0％） was significantly lower than that from the In-patients （71.1％） and ICU-patients （74.4％） groups.The virus distribution was different between the Out-patients group and the other hospitalized groups,while the virus detection rate and distribution characteristics were similar between the In-patients and ICU-patients groups.The coinfection rates of the Out-patients group,the In-patients group,and the ICU-patients group were 15.6％,50.0％ and 35.8％,respectively.In addition to respiratory syncytial virus （RSV） and adenovirus （ADV）,human rhinovirus （HRV） was frequently detected from children with serious illnesses,followed by human metapneumovirus （hMPV）,human bocavirus （HBoV） and coronaviruses.Parainfluenza virus 3 （PIV3） was detected in children with lower respiratory illness,but rarely from those with serious illnesses in the ICU-patient group.Conclusion In addition to so-called common respiratory viruses,virus detection in children with ARI should include those thoucht to be uncommon respiratory viruses,especially when there are severe ARI-related clinical illnesses.     

Efficacy of solution form of ethylenediaminetetraacetic acid on removing smear layer of root canal at different exposure time In Vitro

Summary： This study was aimed to evaluate the effectiveness of solution form of 17% ethylenediaminetetraacetic acid （EDTA） on removing smear layer of root canals at different exposure time periods and to provide scientific basis for EDTA as a choice of root canal irrigation in clinical practice. Twenty-five single-rooted teeth were randomly divided into 5 groups： control group （group A） was given 2.5% NaOC1, and 4 experimental groups were given 2.5% NaOC1 and 17% EDTA, including groups B, C, D and E with exposure time of 1, 3, 5 and 7 min, respectively. After preparation of the root canals, the teeth were split along their longitudinal axis, and the root sections were examined under scanning elec- tron microscope for evaluation of smear layer removal and erosion on the surface of the root canal walls. The specimens in group B showed presence of smear layer on the walls of the root canal with no statistical difference from that in group A （P〉0.05）. In groups C and D, partial removal of smear layer was obtained, and there was no significant difference between the two groups （P〉0.05）, but there was significant difference in removal of smear layer between group C and group B （P〈0.05）. Root canal walls in group E specimens showed almost complete removal of smear layer, and the removal of smear layer was significantly different from that in group D （P〈0.01）. There was no significant change in the structure of the surface of root canal for each sample. It was concluded that combined irrigation with 17% EDTA and 2.5% NaOC1 could remove the smear layer with no significant alteration in dentinal structure when the chelating agent was applied for 7 min. At 3 and 5 min of application, partial removal of smear layer was observed and at 1 min negligible removal of smear layer was achieved.     

Picture perception in Chinese dyslexic children: an eye-movement study

Background Currently, whether or not there is visuospatial impairments in Chinese dyslexic children is still a matter of discussion. The relatively recent application of an eye-tracking paradigm may offer an opportunity to address this issue. In China, in comparison with reading studies, there have not been nearly as many eye movement studies dealing with nonreading tasks such as picture identification and whether Chinese children with dyslexia have a picture processing deficit is not clear. The purposes of the present study were to determine whether or not there is visuospatial impairments in Chinese dyslexic children. Moreover, we attempted to discuss whether or not the abnormal eye movement pattern that dyslexic subjects show during reading of text appropriate for their age is a consequence of their linguistic difficulties. Methods An eye-link II High-Speed Eye Tracker was used to track the series of eye-movement of 19 Chinese dyslexic children and 19 Chinese normal children. All of the subjects were presented with three pictures for this eye-tracking task and 6 relative eye-movement parameters, first fixation duration, average fixation duration, average saccade amplitude, mean saccade distance, fixation frequency and saccade frequency were recorded for analysis. Results Analyzing the relative parameter among three pictures, except for the fixation frequency and the saccade frequency, other eye-movement parameters were significantly different among the three pictures （P 〈0.05）. Among the three pictures, the first fixation duration was longer, and the average fixation duration, the average saccade amplitude and the mean saccade distance were shorter from picture 2 to picture 3. Comparing all eye-movement parameter between the two groups, the scores of average saccade amplitude （P=-0.017） and the mean saccade distance （P=0.02） were less in the dyslexia group than in the normal group （P 〈0.05）, other parameters were the same in the two different groups （P 〉0.05）. Conclusions The characteristics of the pictures can significantly influence the visuospatial cognitive processing capability of the Chinese children. There is a detectable disability for the Chinese dyslexic children in the visuospatial cognitive processing： their saccade amplitude and mean saccade distance are shorter, which may be interpreted as specific for their reading disability.     

Liquid Chromatography-tandem Mass Spectrometry for Analysis of Acylcarnitines in Dried Blood Specimens Collected at Autopsy from Neonatal Intensive Care Unit

Objective To investigate the feasibility of analyzing acylcarnitine in dry filter-paper blood spots by liquid chromatography-tandem mass spectrometry（LC-MS/MS） which could be applied to detect inborn errors of metabolism in neonates.Methods We obtained filter-paper blood from 26 dead infants from a neonatal intensive care unit（NICU） between October 1,2008 and September 30,2009.Acylcarnitine and amino acid profiles were obtained with LC-MS/MS.Four infants underwent routine autopsy.The postmortem blood specimens were compared with newborn blood specimens,and with specimens obtained from older infants with metabolic disorders.Results Of all the 26 patients,5（19.2%） were diagnosed as having different kinds of diseases：3 with methylmalonic acidemia（the concentration of C3,and the ratio of C3/C16,C3/C2 increased）,1 with maple syrup urine disease（the concentration of leucine and isoleucine increased）,and 1 with isovaleric aci-demia（the concentration of C5 increased）.Conclusions Postmortem metabolic test can explain infant deaths and provide estimates of deaths attributable to inborn errors of metabolism in NICU.LC-MS/MS is suitable for analysis of postmortem specimens and can be considered for routine application in NICU autopsy.     

KumaFix fixation for thoracolumbar burst fractures: a prospective study on selective consecutive patients

Background Short-segment U-shaped pedicle screw fixation has been widely used to treat thoracolumbar burst fracture.Some studies have reported the disadvantages of traditional U-shaped pedicle screw,which included a relatively high rate of adjacent segment degeneration and screw failure,including screw pullout and breakage.The purpose of this study was to assess the efficacy of open reduction and fixation using KumaFix fixation system in treatment of thoracolumbar burst fractures.Methods From June 2011 to June 2012,45 consecutive patients with thoracolumbar burst fractures were enrolled.They were randomly assigned to treatment with KumaFix （the treatment group,n=23） or traditional U-shaped pedicle screw （the control group,n=22）.The patients were followed up postoperatively and were assessed with regard to radiologic and clinical outcomes.Radiologic outcomes were assessed mainly on the basis of Cobb angle and vertebral wedge angle.Clinical outcomes were evaluated mainly with use of Visual Analog Scale （VAS） for pain and the Oswestry Disability Index （ODI） Questionnaire.Results All patients were followed up from 9 to 22 months.There were no significant differences between the two groups with regard to preoperative indices.The operation time in the treatment group was significantly lower than that in the control group.Preoperative Cobb angles and vertebral wedge angles in two groups were significantly decreased after surgery,and these have been well maintained at the last follow-up with mild correction losses.The results of clinical outcome showed lower VAS and ODI scores in two groups compared with those preoperative,and the treatment group had greater improvement on the ODI compared with the control group at the last follow-up.Conclusions Compared with traditional U-shaped pedicle screw,KumaFix fixation system can achieve gradual,controlled reduction,provide enough space for bone implantation,and avoid acceleration of adjacent segment degeneration.It is an effective and reliable technique to treat thoracolumbar burst fractures.     

Expression of Beclin1 in osteosarcoma and the effects of down-regulation of autophagy on the chemotherapeutic sensitivity

To explore the expression of Beclin1 in osteosarcoma and investigate the effects of down-regulation of autophagy on the chemotherapeutic sensitivity to cisplatin （DDP）, the expression of Beclin1 in 28 specimens of osteosarcoma （group A） and 19 specimens of normal bone tissues （group B） were immunohistochemically detected. The expression of Beclin1 mRNA in MG63 cells treated with different concentrations of DDP was examined with RT-PCR. After down-regulation of autophagy in MG63 cells by an autophagy inhibitor, 3-methyladenine （3-MA）, the cell proliferation inhibition rate of MG63 cells treated with DDP was evaluated by using the MTT assay. The positive rates of Beclin1 were 67.85% in group A and 94.73% in group B. Its expression was lower in osteosarcoma than in normal bone tissues, with a significant difference found between them （P〈0.05）. RT-PCR showed that the expression of Beclin1 mRNA in the cells treated with high-dose DDP were higher than that in the non-treated cells, and no significant difference in the expression of Beclin1 mRNA was found between the cells treated with low-dose DDP and the non-treated cells. There was a positive correlation between the level of Beclin1 mRNA expression and the concentration of DDP. MTT assay showed that the proliferation inhibition rates of the cell treated with 3-MA and DDP combined were substantially increased when compared with those treated with DDP alone （P〈0.01）. This study demonstrated that autophagy may be implicated in the carcinogenesis of osteosarcoma, and DDP may induce autophagy in the MG63 cells. It also suggests that the down-regulated autophagy could increase chemotherapeutic sensitivity of DDP to osteosarcoma.     

Effect of Etching Treatment on the Bond Strength of a New Self-Adhesive Resin Cement

Objective The aim of this study was to evaluate the effect of etching treatment on the bond strength of new self-adhesive resin cement （RelyX Unicem, 3M ESPE） to enamel and dentin. Methods Flat buccal dentin surface and mesial/distal enamel surface were made on 36 human third molars （freshly extracted and non-carious） with diamond bur. The Specimens were divided into 3 groups （n=12） according to different etching treatment. Each surface was treated with Unicem, phosphoric acid etching combined with Unicem, and Panavia F, respectively. In each group, shear bond strength were tested on 10 specimens, and the other 2 specimens were observed by SEM. Results Statistical analysis showed that there was no significant difference between Unicem group （12.84±2.29MPa） and Panavia F group （14.93±3.73MPa） on dentin bonding （P〉0.05）, and the bonding strength of them were higher than that of Unicem combined with phosphoric acid etching （9.12±1.54MPa） （P〈0.05）. For enamel bond strength, no significant difference was observed between group which used Panavia F （17.99±3.66MPa） and phosphoric acid etching combined with Unicem group （17.24±1.62）, while both of them was higher than that of Unicem （6.47±1.54MPa） （P〈0.05）. Conclusion Phosphoric acid etching can improve the bonding strength of the self-adhesive resin cement with enamel, but is unnecessary for dentin.     

Inhibitory effect of extract of fungi of <Emphasis Type="Italic">Huaier</Emphasis> on hepatocellular carcinoma cells

This study investigated the inhibitory effect of the extract of fungi of Huaier （EFH） on the growth of hepatocellular carcinoma （HCC） cells. Hep-G2 cells, a human HCC cell line, were cultured in DMEM containing 10% fetal bovine serum and treated with EFH of different concentrations （1, 2, 4, 8 mg/mL） for 24, 48 and 72 h respectively. The apoptosis rate of the cells was flow cytomet-rically measured. Thirty-six tumor-bearing New Zealand rabbits were randomly divided into 3 groups group A （control group）, in which the rabbits were infused with 0.2 mL/kg normal saline via the hepatic artery; group B （transhepatic artery cbemoembolization [TACE] group）, in which the rabbits were given lipiodol at 0.2 mL/kg plus MMC at 0.5 mg/kg via the hepatic artery; group C （TACE ＋ EFH group ）, in which EFH （500 mg/kg） were orally administered after TACE. Two weeks after TACE, the rabbits were sacrificed and the implanted tumors were sampled. The tumor volume and the necrosis rate were determined. The tumor tissues were immunohistochemically detected for the expressions of factor Ⅷ, VEGF, P53, Bax and Bcl-2. The microvessel density （MVD） was calculated by counting the factor Ⅷ-positive endothelial cells. Our results showed that after treatment with EFH the apoptosis rate of Hep-G2 cells was enhanced in a concentration- and time-dependent manner. Two weeks after the treatment, the average tumor volume, the necrosis rate and the growth rate of the implanted tumor in group C were significantly different from those in groups A and B （P〈0.05）. MVD and VEGF expressions were significantly decreased in the group C when compared with those in groups B （P〈0.05 for all）. The Bax expression was weakest in group A and strongest in group C. The expressions of P53 and Bcl-2 were minimal in group C and maximal in group A. There were significant differences in the expressions of P53, Bax and Bcl-2 among the 3 groups （P〈0.05 for all） and there was significant difference between group B and group C （P〈0.05）. It was concluded that EFH could suppress not only the growth of HCC cells but also tumor angiogenesis and it can induce the apoptosis of HCC cells. EFH serves as an alternative for the treatment of HCC.