Effects of miR-155 on apoptosis of chronic myeloid leukemia cells and expression of heat shock proteins / 安徽医科大学学报

Objective @# To explore the effects of microRNA-155 (miR-155) on apoptosis of chronic myeloid leukemia ( CML) cells，and the influence of miRNA-155 regulating the expression of heat shock proteins ( HSP) 27， HSP60，HSP70．@*Methods @#Reverse transcription-quantitative real-time PCR ( RT-qPCR) was used to detect the expression levels of miR-155 in CML-resistant imatinib (IM) cell line K562-G and CML cell line K562 ．K562-G cells were infected with the lentivirus carrying miR-155 or the negative control lentivirus ，and they were named miR-155 group and control group．The effect of miR-155 on the proliferation of drug-resistant cells was detected by cell counting kit-8 ( CCK-8) method. RT-qPCR and Western blot were used to detect the effect of miR-155 on the expression of heat shock proteins HSP27，HSP60，HSP70．Flow cytometry was used to detect the percentage of cell apoptosis in miR-155 group and control group. @*Results @#ompared with K562 cells，miR-155 showed low expres- sion in K562-G cells (P ＜0. 05) ．The proliferation of miR-155 group cells decreased significantly from the 36th hour (P＜0. 05) ．Compared with the control group，in the miR-155 group，HSP60 and HSP70 increased (P < 0. 05) ，while HSP27 decreased (P＜0. 01) ．The apoptosis rate of miR-155 group was higher than that of control group (P＜0. 05) ．@*Conclusion @#miR-155 promotes the apoptosis of chronic myeloid leukemia cells，increases the expression of HSP60 and HSP70，and decreases the expression of HSP27 .

Association study of human leukocyte antigen (HLA) variants and idiopathic pulmonary fibrosis.

Introduction: Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial pneumonia marked by progressive lung fibrosis and a poor prognosis. Recent studies have highlighted the potential role of infection in the pathogenesis of IPF and a prior association of the HLA-DQB1 gene with idiopathic fibrotic interstitial pneumonia (including IPF) has been reported. Due to the important role that the Human Leukocyte Antigen (HLA) region plays in the immune response, here we evaluated if HLA genetic variation was associated specifically with IPF risk. Methods: We performed a meta-analysis of associations of the HLA region with IPF risk in individuals of European ancestry from seven independent case-control studies of IPF (comprising a total of 5,159 cases and 27,459 controls, including the prior study of fibrotic interstitial pneumonia). Single nucleotide polymorphisms, classical HLA alleles and amino acids were analysed and signals meeting a region-wide association threshold p<4.5×10-4 and a posterior probability of replication >90% were considered significant. We sought to replicate the previously reported HLA-DQB1 association in the subset of studies independent of the original report. Results: The meta-analysis of all seven studies identified four significant independent single nucleotide polymorphisms associated with IPF risk. However, none met the posterior probability for replication criterion. The HLA-DQB1 association was not replicated in the independent IPF studies. Conclusion: Variation in the HLA region was not consistently associated with risk in studies of IPF. However, this does not preclude the possibility that other genomic regions linked to the immune response may be involved in the aetiology of IPF.

Electroacupuncture at acupoints of yangming meridians for sarcopenia: a randomized controlled trial / 中国针灸

OBJECTIVE@#To observe the clinical effect of electroacupuncture at acupoints of yangming meridians for sarcopenia.@*METHODS@#A total of 60 patients with sarcopenia were randomized into an observation group and a control group, 30 cases in each group. In the control group, conventional nutrition intervention for sarcopenia was adopted. In the observation group, on the basis of the treatment in the control group, acupuncture was applied at bilateral Binao (LI 14), Quchi (LI 11), Zusanli (ST 36), Yanglingquan (GB 34), etc.,ipsilateral Quchi (LI 11) and Zusanli (ST 36) were connected to electroacupuncture, with discontinuous wave, 2 Hz in frequency, 1-10 mA in intensity, 2 times a week, with a interval of 3 days. A total of 12-week treatment was required in the two groups. Before and after treatment, the appendicular skeletal muscle mass index (ASMI), grip strength, 6 m-walking time, body fat percentage and body moisture percentage were observed in the two groups.@*RESULTS@#Compared with those before treatment, after treatment, ASMI and grip strength were increased while 6 m-walking time was shortened in the two groups (P<0.05); body fat percentage was decreased while body moisture percentage was increased in the observation group (P<0.05). After treatment, in the observation group, ASMI, grip strength and body moisture percentage were increased (P<0.05), 6 m-walking time was shortened and body fat percentage was decreased (P<0.05) compared with those in the control group.@*CONCLUSION@#Electroacupuncture at acupoints of yangming meridians can effectively improve the skeletal muscle mass, muscle function, body fat percentage and body moisture percentage in patients with sarcopenia, and make the distribution of muscle and fat more reasonable.

Digitalized analysis of the gingival and bone morphology in the maxillary anterior teeth in patient with posterior dental implant / 中华口腔医学杂志

Objective: To explore and analyze the correlation between labial gingival morphology and alveolar bone morphology of maxillary anterior teeth in patients with posterior dental implant, so as to provide reference basis for restoration design and esthetic reconstruction of anterior teeth. Methods: Sixty-four patients [24 males, 40 females (25.6±3.3) years old] who planned to receive posterior dental implant restoration were recruited randomly with the inclusion and exclusion criteria in Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University from May 2020 to May 2021. According to the visibility of periodontal probe through gingival margin, the subjects were divided into thin and thick gingival biotypes, including 29 cases of thin biotype and 35 cases of thick biotype. The 3Shape software was used to perform oral scanning, and cone beam CT (CBCT) was taken for each patient. Geomagic and Mimics software were used to measure and record the labial crown width and length, gingival papilla height, gingival angle, bone papilla height and bone margin angle of maxillary anterior teeth. Results: The crown width length ratios of maxillary central incisors, lateral incisors and canines were 0.85±0.08, 0.80±0.08 and 0.86±0.09 (F=10.71, P<0.01). The height of gingival papilla between maxillary central incisors, between central incisors and lateral incisors, between lateral incisors and canines were (3.93±0.86), (3.47±0.84) and (3.38±0.91) mm respectively (F=7.44, P<0.01), and the height of corresponding bone papilla were (3.44±0.88), (3.12±0.75) and (2.72±0.63) mm respectively (F=14.26, P<0.01). The gingival margin angles of maxillary central incisors, lateral incisors and canines were 88.3°±7.7°, 84.7°±8.9° and 81.2°±6.6° (F=13.15, P<0.01), and the bone margin angles were 103.2°±13.1°, 99.5°±11.2° and 110.6°±13.0° (F=13.25, P<0.01). The crown width length ratio (0.81±0.08), gingival margin angle (82.2°±7.4°) and bone margin angle (99.4°±12.9°) of thin gingival subjects were significantly lower than those of thick gingival subjects (0.85±0.09, 86.5°±8.6°, 108.5°±11.4°) (t=-2.79, 3.63, 5.20, P<0.01). The height of gingival papilla [(3.93±0.81) mm] and bone papilla [(3.43±0.80) mm] in thin gingival subjects were significantly lower than those in thick gingival subjects [(3.34±0.84) and (2.85±0.71) mm, respectively] (t=-4.89, -5.36, P<0.01). The height of labial gingival papilla of upper anterior teeth was positively correlated with that of bone papilla in all patients (r=0.66, P<0.01); the ratio of crown width to length of upper anterior teeth was positively correlated with the angle of bone margin (r=0.42, P<0.01); the height of anterior gingival papilla was negatively correlated with the angle of bone margin (r=-0.58, P<0.01), and the height of bone papilla was negatively correlated with the angle of bone margin (r=-0.82, P<0.01). Conclusions: The crown shape, gingival shape and alveolar bone shape of maxillary anterior teeth were different in different tooth positions. Patients with different periodontal phenotypes had different crown width length ratio, gingival papilla height, bone papilla height, gingival margin angle, and bone margin angle.

Digital analysis of the correlation between gingival thickness and alveolar bone thickness in the maxillary anterior teeth region / 中华口腔医学杂志

Objective: To measure the labial gingival thickness and bone lamella thickness in the maxillary anterior area using digital method, and to analyze the correlation between the two, so as to provide a reference for esthetic restoration and implantation treatment of the upper anterior area. Methods: Fifty-seven patients [23 males, 34 females, (25.8±4.5) years old] who planned to receive posterior dental implant restoration were recruited randomly with the inclusion and exclusion criteria in Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University from May 2020 to October 2020. The 3Shape software was used to perform oral scanning, and cone beam CT (CBCT) was taken for each patient. The image data was fitted and registered by the 3Shape software. The gingival thickness at 2 mm below the gingival margin, bone thickness and gingival thickness at 2 and, 4 mm below the crest of the labial alveolar crest in maxillary central incisors, lateral incisors and canines, were measured. Results: The gingival thickness at 2 mm below the gingival margin of maxillary central incisors, lateral incisors and canines was (1.42±0.21), (1.19±0.17) and (1.23±0.20) mm respectively (F=12.47, P<0.001). The gingival thickness at 2 mm below gingival margin and 4 mm below crest of residual ridge in the male patients were (1.31±0.21) and (0.67±0.22) mm, and those in the female patients were (1.26±0.22) and (0.58±0.19) mm respectively, and there were statistically significant differences in the gingival thickness between the "2 mm below gingival margin" group and the "4 mm below crest of residual ridge" group (t=2.01 and 3.97, P<0.05). There was a positive correlation between gingival thickness and alveolar bone thickness at 2 mm and 4 mm below the crest of residual ridge in maxillary anterior region, and the correlation coefficients (r) were 0.387 and 0.344 respectively (P<0.05). Conclusions: Gingival thickness of maxillary anterior area is related to the tooth position and gender. The gingival thickness of men is greater than that of women.The gingival thickness at 2 and 4 mm below the crest of the alveolar crest is positively correlated with the thickness of the alveolar bone.

Network Meta-analysis of Chinese patent medicine in treatment of unstable angina pectoris / 中国中药杂志

Network Meta-analysis was used to compare the efficacy and safety of Chinese patent medicines in the treatment of unstable angina pectoris. PubMed, Cochrane Library, CNKI, Wanfang, VIP and other databases were retrieved by computers from the establishment of the databases to June 2020. Randomized controlled trials(RCTs) of Chinese patent medicines for the treatment of unstable angina pectoris were collected. Two investigators independently screened out the literatures, and extracted data according to the inclusion and exclusion criteria. The quality of the included RCTs was evaluated according to the bias risk assessment tool recommended by the Cochrane System Reviewer Manual, and the Stata 13.0 software was used for data analysis and mapping. Through screening, 28 eligible studies were finally included, with the sample size of 2 885 cases, involving 8 Chinese patent medicines. The results of the network Meta-analysis showed that in terms of total effective rate for angina symptom improvement, the order was as follows: Shenshao Capsules > Naoxintong Capsules > Ginkgo Ketone Ester Dripping Pills > Compound Danshen Dripping Pills > Ginkgo Leaf Tablets > Shexiang Baoxin Pills > Tongxinluo Capsules > Yindan Xinnaotong Soft Capsules; in terms of total effective rate for ECG curative effect, the order was as follows: Ginkgo Ketone Ester Dripping Pills>Compound Danshen Dripping Pills > Tongxinluo Capsules > Shenshao Capsules > Shexiang Baoxin Pills > Yindan Xinnaotong Soft Capsules; in terms of hypersensitivity-C-reactive protein curative effect, the order was as follows: Tongxinluo Capsules > Shenshao Capsules > Ginkgo Leaf Tablets>Compound Danshen Dropping Pills> Shexiang Baoxin Pills > Naoxintong Capsules > Yindan Xinnaotong Soft Capsules > Ginkgo Ketone Ester Dropping Pills. Chinese patent medicine combined with conventional therapy can improve the clinical efficacy of unstable angina pectoris. Due to the differences in the quantity and quality of the included studies, the order results of Chinese patent medicines need to be further verified.

Minimal invasive microscopic tooth preparation based on endodontic, periodontal and functional health / 华西口腔医学杂志

Tooth preparation is the primary and core operation technique for dental esthetic restoration treatment, due to its effect of providing restoration space, bonding interfaces and marginal lines for dental rehabilitation after tooth tissue reduction. The concept of microscopic minimal invasive dentistry put forward the issue of conducting high-quality tooth preparation, conserve tooth-structure, protect vital pulp and periodontal tissue simultaneously. This study reviewed the concepts, physiology background, design and minimal invasive microscopic tooth preparation, and in the meantime, individualized strategies and the two core elements of tooth preparation (quantity and shape) are listed.

Association of thrombelastogram with postoperative hemorrhage after total joint arthroplasty by structural equation modeling / 中国组织工程研究

BACKGROUND: Postoperative anticoagulant therapy after hip and knee arthroplasties has been included in the perioperative management guidelines. However, the application of anticoagulant drugs accompanies with the risk of bleeding. Routine coagulation tests provide limited information about the quality of clots because they identify only the first stage of clotting, while thrombelastography provides a comprehensive assessment of coagulation function. But its practicality remains controversial and the research for bleeding after joint replacement is little reported. OBJECTIVE: To explore the distribution of thrombelastography parameters (time to initial fibrin formation, clotting time, α angle, and maximum amplitude) and to analyze the correlation of the four parameters with postoperative blood loss, thereby providing guidance for improving the safety and effectiveness of anticoagulant therapy. METHODS: Totally 148 patients with detection of thrombelastogram after arthroplasty from August 2015 to March 2017 in Sun Yat-sen Memorial Hospital, Sun Yat-sen University were enrolled, including 76 cases of total hip arthroplasty and 72 cases of total knee arthroplasty. Thrombelastography data were collected on day 1 postoperatively, and the perioperative blood loss was calculated. Structural equation modeling of each group was constructed to investigate the relationship of four parameters and total blood loss. RESULTS AND CONCLUSION: (1) In the structural equation modeling of hip and knee arthroplasties, the root mean square error of approximation was less than 0.08, goodness-of-fit index, adjusted goodness-of-fit index, normed fit index and comparative fit index was all higher than 0.9, and Parsi-mony goodness-of-fit index was less than 2, so the theoretical model was matched with the data. (2) There was a correlation of postoperative hemorrhage with time to initial fibrin formation, clotting time, α angle, and maximum amplitude. (3) That is to say, thrombelastogram can be used as an efficient tool in predicting bleeding after hip and knee arthroplasties. Future study based on this research will further verify the correlation and provide more information for its clinical practice.

Integrative drug efficacy assessment of Danggui and European Danggui using NMR-based metabolomics.

Danggui (DG) is a commonly used herbal drug in traditional Chinese medicine, and usually adulterated with European Danggui (EDG) due to the increasing demand. In present study, global metabolic profiling with NMR coupled with integrative drug efficacy evaluation methods was performed to compare and discover underlying blood-enriching regulation mechanisms of DG and EDG on blood deficiency rats induced by acetyl phenylhydrazine (APH). Totally, the contents of 12 key metabolites in serum and 4 in urine of DG group, 7 in serum and 4 in urine of EDG group were significantly reversed in comparison with model group. DG was more effective than EDG as revealed by the relative distance, efficacy index and similarity analysis. The metabolism pathways analysis showed that the better effect of DG maybe related with the regulatory effect on valine, leucine and isoleucine biosynthesis, synthesis and degradation of ketone bodies, glycine, serine and threonine metabolism, as well as nicotinate and nicotinamide metabolism. The results presented here showed that metabolomic coupled with efficacy index and similarity analysis made it possible to disclose the subtle biological difference between DG and EDG, which highlight the potential of metabolomic approach to quantitatively compare the pharmacological effect of the herbal drugs.

[Discrimination of patients with Xiao-Chaihu Tang syndrome using 1H NMR metabonomics and partial least square analysis].

1H NMR metabonomics approach was used to reveal the chemical difference of urine between patients with Xiao-Chaihu Tang syndrome (XCHTS) and healthy participants (HP). The partial least square method was used to establish a model to distinguish the patients with Xiao-Chaihu-Tang syndrome from the healthy controls. Thirty-four endogenous metabolites were identified in the 1H NMR spectrum, and orthogonal partial least squares discriminant analysis showed the urine of patients with Xiao-Chaihu Tang syndrome and healthy participants could be separated clearly. It is indicated that the metabolic profiling of patients with Xiao-Chaihu Tang syndrome was changed obviously. Fifteen metabolites were found by S-pot of OPLS-DA and VIP value. The contents of leucine, formic acid, glycine, hippuric acid and uracil increased in the urine of patients, while threonine, 2-hydroxyisobutyrate, acetamide, 2-oxoglutarate, citric acid, dimethylamine, malonic acid, betaine, trimethylamine oxide, phenylacetyl glycine, and uridine decreased. These metabolites involve the intestinal microbial balance, energy metabolism and amino acid metabolism pathways, which is related with the major symptom of Xiao-Chaihu Tang syndrome. The patients with Xiao-Chaihu Tang syndrome could be identified and predicted correctly using the established partial least squares model. This study could be served as the basis for the accurate diagnostic and reasonable administration of Xiao-Chaihu-Tang syndrome.

[Comparison of chemical composition between raw and vinegar-baked Paeoniae Radix Alba using NMR based metabolomic approach].

To compare the chemical change of Paeoniae Radix Alba (PRA) after vinegar-baking processing, as well as the effect of vinegar types exerted on the processing, 1H NMR-based metabolomic approach combined with multivariate statistical analysis was used to investigate the different metabolites between the raw and two vinegar-baked PRA. More than thirty metabolites were identified in the 1H NMR spectrum of PRA, and the multivariate statistical analysis showed that raw and two vinegar-baked PRA could be separated obviously. After vinegar-baking, the contents of isoleucine, lactate, alanine, arginine, albiflorin, and 5-hydroxymethyl furfural (5-HMF) elevated, while those of sucrose, paeoniflorin and its analogues (calculated by benzoate) decreased. The chemical compositions of two vinegar-baked PRA were also different. Shanxi vinegar- baked PRA showed higher levels of leucine, isoleucine, valine, and albiflorin, while rice vinegar-baked PRA contained more sucrose and paeoniflorin's analogues (calculated by benzoate). And the chemical changes in Shanxi vinegar-baked PRA were greater than those of rice vinegar-baked PRA. The results revealed the chemical differences between raw and vinegar-baked PRA, as well as the influence of vinegar type on processing, in a holistic manner, the results obtained suggested that the correlations between the chemical change and the drug action after processing, as well as the vinegar type used in processing, should be further studied.

Changes of T-cell clonality after induction-cultivation of peripheral T lymphocytes in adoptive immunotherapy for leukemias / 中国实验血液学杂志

This study was purposed to analyze the changes of T-cell clonality after induction of peripheral T lymphocytes by autogenous DC and cytokines in the preparation of adoptive immunotherapy for leukemias. The bone marrow and peripheral blood from 21 leukemia patients at remission stage after treatment and subjected to adoptive immunotherapy were collected. Their DCs and T-cells were stimulated with cytokines and then were mixed to activate T-cells. T-cell receptor beta variable region (TCRBV) families were amplified by RT-PCR, and genescan method and sequencing of the PCR products were used to observe the clonality changes of T-cells before and after the induction and cultivation of T-cells. The flow cytometry was used to identify CD3(+), CD4(+), CD8(+), CD3(+)CD56(+) and CD4(+)CD25str(+)FOXP3(+) cells to disclose the ratio change of cytotoxic T lymphocytes (CTL), helper T-cells, regulatory T-cells and NK T-cells before and after induction and cultivation of T-cells. The results showed that in the 21 patients, most of the 24 TCRBV families presented as oligoclonal distribution on genescan, several families were not expressed, and only a few families remained polyclonal. TCRBV24 was found to be oligoclonal in all of the 21 patients. DNA sequence analysis of TCRBV24 revealed a common motif of VAG in CDR3 in 3 cases and a common motif of GGG in CDR3 in 2 cases. In patient 5, both TCRBV 24 and TCRBV8 contained the same motif of GGG in CDR3. The identical motif in these patients may suggest that these T-cells recognize the same antigen. The peripheral lymphocytes demonstrated recovery of clonal profile on genescan from oligoclonal profile and absence of several families before the induction and cultivation to typical polyclonal profile in all TCRBV families after the induction by DC and cytokines for 13 days. After the induction and cultivation, the number of lymphocytes increased to 3.38 +/- 1.20 times. CD3(+), CD4(+), CD8(+), CD3(+)CD56(+) and CD4(+)CD25str(+)FOX P3(+) cells were 71.1 +/- 11.8%, 26.7 +/- 11.4%, 35.7 +/- 12.9%, 3.1 +/- 1.6% and 0.12 +/- 0.1% respectively before the induction and cultivation, and changed to 95.4 +/- 3.2% (p < 0.01), 27.0 +/- 13.1% (p > 0.01), 55.5 +/- 13.8% (p < 0.01), 9.8 +/- 6.1% (p < 0.01) and 0.22 +/- 0.18% (p < 0.01) respectively after the induction and cultivation. It is concluded that the major action of this induction and cultivation method on T-lymphocytes in vitro is the promotion of CTL and NK T-cell proliferation. In leukemic patients at the remission stage, the TCRBV profile is characterized by the oligoclonal proliferation of T-lymphocytes. Several proliferated clones may have the same motif in CDR3, suggesting the recognition of the same antigen by these lymphocyte clones. Cytokine induction and co-culture with autogenous DCs can stimulate the T-lymphocytes to recover their immunocompetence as manifested by the polyclonal profile and the proliferation of CTL and NK-T cells.

An 8-year follow-up study of Cerec2 computer aided design and computer aided manufacture of all-ceramic crowns / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the clinical performance of the crowns made by Cerec2 computer aided design and computer aided manufacture (CAD/CAM) system.</p><p><b>METHODS</b>Twenty four teeth were restored with Cerec2 CAD/CAM crowns. Eight years after delivery of the prostheses, the all-ceramic crowns were evaluated using modified standard of California Dental Association quality evaluation system. Patients filled out a satisfaction questionnaire at the same time. And Kaplan-Meier analysis was carried out.</p><p><b>RESULTS</b>Three out of 24 restorations were rated as failure. Kaplan-Meier analysis showed that the success rate of Cerec2 crowns eight year following delivery was 88%.</p><p><b>CONCLUSIONS</b>Crowns made by Cerec2 CAD/CAM system can survive in oral condition and function well for 8 years.</p>

Macrophage migration inhibitory factor in acute lung injury: expression, biomarker, and associations.

The macrophage migration inhibitory factor (MIF), a pro-inflammatory cytokine central to the response to endotoxemia, is a putative biomarker in acute lung injury (ALI). To explore MIF as a molecular target and candidate gene in ALI, the MIF gene and protein expression were examined in murine and canine models of ALI (high tidal volume mechanical ventilation, endotoxin exposure) and in patients with either sepsis or sepsis-induced ALI. MIF gene expression and protein levels were significantly increased in each ALI model, with serum MIF levels significantly higher in patients with either sepsis or ALI compared with healthy controls (African- and European-descent). The association of 8 MIF gene polymorphisms (single-nucleotide polymorphisms (SNPs)) (within a 9.7-kb interval on chromosome 22q11.23) with the development of sepsis and ALI in European-descent and African-descent populations was studied next. Genotyping in 506 DNA samples (sepsis patients, sepsis-associated ALI patients, and healthy controls) revealed haplotypes located in the 3' end of the MIF gene, but not individual SNPs, associated with sepsis and ALI in both populations. These data, generated via functional genomic and genetic approaches, suggest that MIF is a relevant molecular target in ALI.

Effect of interleukin-6 on the chondrocytes in the cartilage endplate of rabbits in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the effect of interleukin-6 (IL-6) on the biological behaviors of the chondrocytes in the cartilage endplate of rabbits.</p><p><b>METHODS</b>Chondrocytes isolated from the cartilage endplate of New Zealand rabbits, verified for their biological characteristics by such means as toluidine blue staining for type II collagen, were treated with IL-6 at different concentrations. The proliferation of the chondrocytes was evaluated by MTT assay at different time points following the treatment, the cell cycle changes were determined by flow cytometry and the changes of aggrecan and type II collagen mRNAs detected by RT-PCR.</p><p><b>RESULTS</b>At the concentrations of 10, 50 and 100 ng/ml, IL-6 did not obviously affect the rate of chondrocyte proliferation. IL-6 at 50 ng/ml resulted in no obvious changes of the cell cycle of the chondrocytes, but significantly decreased the expression of collagen IIa mRNA.</p><p><b>CONCLUSION</b>IL-6 has no effect on the proliferation and cell cycle of the chondrocytes, but at higher concentrations, it inhibits matrix synthesis of the chondrocytes to promote intervertebral disc degeneration.</p>

The risk factors and preventive strategies of heterotopic ossification after artificial disc replacement in lumbar spine / 中华外科杂志

<p><b>OBJECTIVE</b>To analyze the risk factors of heterotopic (HO) ossification after total lumbar disc replacement and probe the preventive strategies for it.</p><p><b>METHODS</b>The radiographs and clinical data of 78 discs in 65 patients who received artificial lumbar disc replacement (ADR) from April 1998 to December 2003 were analyzed retrospectively by two radiologists and one orthopaedic surgeon and then postoperative HO were graded according to McAfee system. The bony formations in disc spaces, time of HO were found, and range of motion (ROM) of the operated levels were measured on radiographic films. In addition, the risk factors such as preoperative peri-annulus ossification, bony endplates injuries, and subsided or mal-position of the prostheses were also analyzed by Logistic regression analysis.</p><p><b>RESULTS</b>Postoperative HO was found in 10 spaces of 9 cases. Class I of HO were occurred in 7 patients at means 2.1 years postoperatively with normal range of motion preserved. Three of them turned into class II or III with 10 degrees of mean ROM in the following 2.5 years. Another 2 (2/9) cases with preoperative peri-annulus ossification had bridging trabecular bone (class III) between the endplates and 9 degrees of ROM 2 years after surgery, then turned into class IV at 6 years with 0 degrees and 4 degrees of motion in the operated levels. As the risk factors of HO, preoperative annulus ossification (2 cases), bony endplates injuries (5 cases), mal-positioned prostheses (2 cases) and subsided prostheses (2 cases) were found simultaneity with significant positive relation to HO occurred (P < 0.05).</p><p><b>CONCLUSIONS</b>Factors such as preoperative ossification of annulus, endplate injuries, prosthesis subsided and mal-position would have higher risks to have HO occurred after ADR, but ROM of most affected levels are preserved. Strict control indication and avoid all above risk factors can prevent HO occurring effectively.</p>

Design and experiment of the pedicle aiming device for the cervical spine / 中国医学科学院学报

<p><b>OBJECTIVE</b>To probe the accuracy and safety of using an aiming device in the transpedicular fixation of cervical spine.</p><p><b>METHODS</b>Eight cervical specimens were obtained. We used the computed tomography (CT) to scan C3 to C7, measured the medial angle of the pedicle, and determined the location of the pedicle projecting on the articular process. Then we took the oblique X-ray film, measured the cephalic/caudal angle of the pedicle, and determined the location of the pedicle projecting on the articular process. All the specimens were equally divided into two groups. Screws of 2.8 mm x 30 mm, were used. Specimens in one group were inserted with the transpedicular screw manually, while specimens in the other one inserted with the transpedicular screw using a self-designed aiming device that can be modulate at the three dimensions according to the angles of the pedicles.</p><p><b>RESULTS</b>The first group totally had 40 screws from C3 to C7. There were 13 screws in the pedicle, 9 violated the walls of the pedicle but not involved the adjunct structure, and 18 injured the important structure such as spinal cord, verteberal artery, or nerve root. In the other group, only 4 screws violated the walls of the pedicle but not involved the adjunct structure, and the others all in the pedicles. The difference was of statistical significance (P < 0.01).</p><p><b>CONCLUSION</b>In the cervical spine, transpedicular fixation using an aiming device can improve the accuracy and safety during operation.</p>

The study on fabrication of dental restoration using PMMA-ZrO2 composites via CAD/CAM / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To obtain dental restorations by machining PMMA-ZrO2 organic-inorganic composites with the dental CAD/CAM system.</p><p><b>METHODS</b>Partially sintered Zirconia compacts (PSZC) were prepared via isostatic pressing and partially sintering, with Zirconia nanopowder as raw materials. PMMA-Zirconia organic-inorganic composites were prepared by vacuum infiltrating the prepolymerized MMA into the PSZC, followed by in-situ polymerization. The mechanical properties and machinability of composites were studied. The composites were machined on the dental CAD/CAM system to obtain dental restoration.</p><p><b>RESULTS</b>At 71.44% TD of PSZC, the composite had a 3-point bending strength of (202.56 +/- 3.09) MPa, fracture toughness of (4.30 +/- 0.16) MPa.m(1/2), elasticity modulus of (58.71 +/- 1.98) GPa, and Vickers hardness of (3.82 +/- 0.34) GPa, respectively. A premolar crown was fabricated by CAD/CAM system in 16 mins, and was verisimilitude, without any cracks.</p><p><b>CONCLUSIONS</b>The composite at 71.44% TD of PSZC has good mechanical properties and dental restorations can be manufactured by PMMA-Zirconia composites via dental CAD/CAM system.</p>

Influence of eugenol-containing temporary cement on efficacy of dentin-bonding systems / 中华口腔医学杂志

<p><b>OBJECTIVE</b>This study investigated the influence of eugenol-containing temporary cement on the efficacy of two relatively new dentin-bonding systems.</p><p><b>METHODS</b>Thirty-two freshly extracted bovine central incisors were randomly divided into four groups. Dentin was exposed and polished with 320#, 400#, and 600# sand papers. After embedded, Group 3 and 4 specimens were covered with ZOE. Specimens in Group 1 and 2 were served as control. All specimens were stored for 1 week in distilled water at 37 degrees C. Then, the ZOE was mechanically removed. The dentin surfaces of Group 1 and 3 were treated with Prime & Bond NT bonding system and the dentin surfaces of Group 2 and 4 were treated with GLUMA adhesive system according to manufacturer's instructions. Thereafter composite resin columns (6 mm diameter, 2 mm high) were applied. After specimens stored in distilled water at 37 degrees C for 24 hours, the shear bond testing was carried out using a SHIMADZU universal testing machine with a cross-head speed of 0.5 mm/minute. The mode of failure was examined using SEM. The data were analyzed using ANOVA test at a significance level of 0.05.</p><p><b>RESULTS</b>The medians of shear bond strength for each group were as follows: Group 1 (Prime & Bond NT) 9.57 MPa, Group 3 (Prime & Bond NT + ZOE) 10.72 MPa, Group 2 (GLUMA) 16.89 MPa, Group 4 (GLUMA + ZOE) 16.78 MPa. Group 1 and 3 had significantly lower bonding strength than did Groups 2 and 4. But no significant difference was found between the control groups and the groups treated with ZOE temporary cement.</p><p><b>CONCLUSION</b>Pretreatment of the dentin with ZOE temporary cement has no adverse influence on the efficacy of two relatively new dentin-bonding systems.</p>

Analysis of complications after treatment of femoral intertrochanteric fractures with internal fixation / 中华创伤骨科杂志

Objective To analyze causes for postoperative fixation-related complications of femoral in- tertrochanteric fractures treated with dynamic hip screws(DHS)and dynamic condylar screws(DCS).Methods From January 1995 to December 2004,215 cases of intertrochanteric fracture were treated with DHS/DCS.Their postoperative fixation-related complications were analyzed to find out the causes.Results All cases were followed up for 13 to 72 months(mean,32 months).The rate of excellent and good functional recovery of hip was 94.0%. Postoperative internal-fixation-related complications occurred in 31 cases,including hip varus in 14 cases who had posterior intertrochanteric fragments,delayed union of fracture in 12 cases who had fractured calcar and lesser trochanter and massive dissection of soft tissues,and cutting-out of lag screws in five cases,three of whom had to receive prosthetic replacement.Conclusions Unsuitable implant selection is an important factor leading to postoperative fixation-related complications.Unstable fracture,serious osteoporosis and unsatisfactory reduction will increase the incidence of complications.