Biomechanical properties of cervical traction under neck muscle force / 医用生物力学

Objective To establish a three-dimensional(3D) finite element model of cervical vertebrae (C1-7), and study its biomechanical properties under muscle force by cervical traction, so as to provide references for clinical treatment. Methods On the basis of nonlinear finite element model of normal cervical vertebrae and combined with clinical traction methods, cervical traction at the extension angle of 0°, 10°, 20°, 30°, 40° under the same traction weight, was simulated by finite element analysis (FEA) software to obtain and select the joint force and muscle force that were appropriate for FEA on the model. Results In the process of cervical extension by traction, under the muscle force, the average maximum equivalent stress of cervical vertebrae, intervertebral disc and uncovertebral joints increased by 4.86, 1.79, 0.69 MPa, respectively, and the average maximum relative displacement of cervical vertebrae in sagittal and vertical axis direction increased by 11.1, 1.26 mm, respectively. The biomechanical properties of cervical traction were similar to the FEA results reported in the literature. Conclusions Neck muscles play an active role in promoting the stress and displacement of cervical vertebrae, intervertebral discs and uncovertebral joints and it should be taken into consideration when performing cervical traction in clinic. In addition, the traction angle should not be too large: 0°-20° is generally recommended as a relatively safe angle range at the initial stage.

Biomechanical properties of cervical traction under neck muscle force / 医用生物力学

Objective To establish a three-dimensional(3D) finite element model of cervical vertebrae (C1-7),and study its biomechanical properties under muscle force by cervical traction,so as to provide references for clinical treatment.Methods On the basis of nonlinear finite element model of normal cervical vertebrae and combined with clinical traction methods,cervical traction at the extension angle of 0°,10°,20°,30°,40° under the same traction weight,was simulated by finite element analysis (FEA) software to obtain and select the joint force and muscle force that were appropriate for FEA on the model.Results In the process of cervical extension by traction,under the muscle force,the average maximum equivalent stress of cervical vertebrae,intervertebral disc and uncovertebral joints increased by 4.86,1.79,0.69 MPa,respectively,and the average maximum relative displacement of cervical vertebrae in sagittal and vertical axis direction increased by 1 1.1,1.26 mm,respectively.The biomechanical properties of cervical traction were similar to the FEA results reported in the literature.Conclusions Neck muscles play an active role in promoting the stress and displacement of cervical vertebrae,intervertebral discs and uncovertebral joints and it should be taken into consideration when performing cervical traction in clinic.In addition,the traction angle should not be too large:0.-20. is generally recommended as a relatively safe angle range at the initial stage.

Biomechanical properties of cervical traction under neck muscle force / 医用生物力学

Objective To establish a three-dimensional(3D) finite element model of cervical vertebrae (C1-7),and study its biomechanical properties under muscle force by cervical traction,so as to provide references for clinical treatment.Methods On the basis of nonlinear finite element model of normal cervical vertebrae and combined with clinical traction methods,cervical traction at the extension angle of 0°,10°,20°,30°,40° under the same traction weight,was simulated by finite element analysis (FEA) software to obtain and select the joint force and muscle force that were appropriate for FEA on the model.Results In the process of cervical extension by traction,under the muscle force,the average maximum equivalent stress of cervical vertebrae,intervertebral disc and uncovertebral joints increased by 4.86,1.79,0.69 MPa,respectively,and the average maximum relative displacement of cervical vertebrae in sagittal and vertical axis direction increased by 1 1.1,1.26 mm,respectively.The biomechanical properties of cervical traction were similar to the FEA results reported in the literature.Conclusions Neck muscles play an active role in promoting the stress and displacement of cervical vertebrae,intervertebral discs and uncovertebral joints and it should be taken into consideration when performing cervical traction in clinic.In addition,the traction angle should not be too large:0.-20. is generally recommended as a relatively safe angle range at the initial stage.

Analysis of factors associated with lateral lymph node metastasis in mid and low rectal cancer / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the factors associated with lateral lymph node metastasis in middle and low rectal cancer.</p><p><b>METHODS</b>Clinical data of 203 patients with middle and low rectal cancer (within 10 cm from anal verge) undergoing lateral lymph node dissection in the Affiliated Cancer Hospital, Xinjiang Medical University between June 2004 to June 2010, were analyzed retrospectively. Logistic regression analysis was used to screen the associated factors.</p><p><b>RESULTS</b>The total number of harvested lateral lymph node was 3349, and average number was 17 per case. The number of positive lateral lymph node was 221, and the lymph node metastasis ratio was 6.6%(221/3349). Univariate analysis showed that age, family history, tumor length, gross type of tumor, histological type, differentiation, depth of invasion, invasion of circumference, serum CEA, tumor thrombus and upper lymph node metastasis were associated with rectal cancer metastasis(P<0.05). Multivariate analysis showed that age, histological type, infiltration depth, gross type, differentiation degree and upper lymph node metastasis were the independent risk factors of the lateral lymph node metastasis in middle and low rectal cancer(P<0.05).</p><p><b>CONCLUSION</b>For patients who is young, or with poorly differentiated cancers, infiltrative type, T4 cancer, or those with upper lymph node metastasis, lateral lymph resection may be indicated because of high risk of lateral node metastasis.</p>

Interaction of folate deficiency and aberrant profile of DNA methyltransferase 1 in the progression of cervix carcinogenesis / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the interaction of folate deficiency and aberration of DNA methyltransferase 1 (DNMT1) in the progression of cervix carcinogenesis.</p><p><b>METHODS</b>All clinical samples were collected from 80 patients with cervix squamous cell carcinoma (SCC), 105 patients with cervical intraepithelial neoplasm (CINI, n = 52; CINII/III, n = 53) and 53 patients with cervix inflammation (CI). The participants were diagnosed by histology at Shanxi Province Tumor Hospital and Second Hospital of Shanxi Medical University during the period of September 2009 to May 2010. Meanwhile, cervical cancer cell lines Caski and C33A were treated with different concentration of folate. Radioimmunoassay (RIA), Western blotting and real-time PCR were used to detect the levels of serum folate, the expression of DNMT1 protein and mRNA, respectively. The data were analyzed by Student t test, ANOVA, chi-square test and Spearman correlation using SPSS statistical package. The correlation strength between factors and cervical canceration was calculated by OR and 95%CI value. Interaction effect was evaluated by the application of additive effect model.</p><p><b>RESULTS</b>The levels of serum folate (median inter-quartile range) were (2.66 ± 1.82), (2.83 ± 2.23), (3.17 ± 1.91) and (3.21 ± 1.74) ng/ml, the levels of DNMT1 protein (x(-) ± s) were 2.28 ± 0.55, 1.84 ± 0.37, 1.33 ± 0.38 and 0.92 ± 0.29, the Ct-ratio (Ct value of DNMT1/Ct value of β-actin) of DNMT1 mRNA (x(-) ± s) were 1.26 ± 0.13, 1.27 ± 0.12, 1.27 ± 0.12 and 1.33 ± 0.11 in the group of SCC, CINII/III, CINIand CI, respectively. The results showed that the serum folate levels were descended, and the expression levels of DNMT1 protein (χ(2)(tend) = 50.80, P < 0.05) and mRNA (χ(2)(tend) = 17.63, P < 0.05) were increased steadily with the severity of the cervix lesions. Moreover, our results revealed that there was an additive interaction between folate deficiency and high-expression of DNMT1 protein related to the risk of CIN and SCC. And it showed that the relative excess risk of interaction (RERI), attributable proportion of interaction (API) and synergy index(S) was 0.27, 0.14 and 1.40 in CINI group, 0.47, 0.19, 1.46 in CINII/III group, 1.60, 0.31, 1.61 in SCC group, respectively. It was found that folate was able to reduce the proliferation of Caski and C33A cells (r values were 0.954 and 0.969, all P values < 0.05), with 11.4% and 13.6% of growth inhibition at the concentration of 10 µg/ml, 64.8% and 49.4% at 1000 µg/ml in Caski and C33A cells, respectively. The result showed there was an inverse correlation between the levels of folate and DNMT1 protein (r values were -0.859 and -0.914, all P values < 0.05), with 1.96 and 1.92 of expression levels at the concentration of 10 µg/ml, and 1.60 and 1.38 at 1000 µg/ml in Caski and C33A cells, respectively. At folate concentration of 1000 µg/ml, the expression of DNMT1 protein or mRNA was higher in Caski cell than in C33A cell (t values were -4.22 and 3.50, all P values < 0.05).</p><p><b>CONCLUSION</b>Our finding indicated that the low levels of serum folate and high-expression of DNMT1 protein or mRNA seemed to be associated with high risk of cervical cancer and cervix precancerous lesion. Sufficient folate is able to effectively inhibit the growth of cervical cancer cells in vitro, and would counteract transcriptional and posttranscriptional aberration of DNMT1. It suggested that there might be a synergistic action between folate deficiency and aberration of DNMT1 in the progression of cervix carcinogenesis.</p>

Effect of folic acid and DNA methyltransferase 1 on cervical cancer and its precancerous lesion / 中华流行病学杂志

Objective To explore the effect of folic acid and DNA methyltransferase 1 (DNMT1) on cervical cancer and cervix precancerous lesion. Methods 100 patients with cervix squamouscell carcinoma (SCC), 101 patients with cervical intraepithelial neoplasm (CIN) and 109 patients with cervix inflammation (CI) diagnosed by histology were included in this study. Radioimmunoassay (RIA), polymerase chain reaction (PCR) and Western blot were used to detect the levels of serum folate, HPV16 infection and the expression of DNMT1 protein,respectively. Results The average levels of serum folate were (2.60 ± 1.61) ng/ml, (3.14 + 2.08) ng/ml and (3.32+1.74) ng/ml,and the expression of DNMT1 protein were 2.40 + 0.99,1.88 + 0.33 and 0.89 ± 0.29 in the group of SCC, CIN and CI, respectively.The relationship of folate levels and DNMT1 protein expression showed inverse correlation (r=-0.186, P=0.00l). The results in our study indicated that there was an additive interaction between low-level of serum folate and high-expressionof DNMT1 protein related to the risk of CIN and SCC, with OR value as 2.50(95%C/: 1.21-9.22) and 6.03 (95%C/: 2.79-21.72) respectively. The relative excessrisk of interaction (RERI) , attributableproportion of interaction (API) and synergy index (S) were 0.92, 0.36 and 2.59 in the CIN group while 2.47, 0.41 and 1.96 in the SCC group. Conclusion The low level of serum folate and high expression of DNMT1 protein seemed to be associated with high risk of cervical cancer and its precancerous lesion. It suggested that there might be a synergistic action between serum folate and DNMT1 in the progression of cervix carcinogenesis.

Association between intravenous pulse-therapy with immunosuppressant for Graves' ophthalmopathy and changes of peripheral blood T cell subgroup / 第二军医大学学报

Objective: To study the association between the outcomes of intravenous pulse-therapy with immunosuppressants and the changes of peripheral blood T cell subgroup in patients with Graves' ophthalmopathy (GO). Methods: Fifty-eight patients with GO were randomized into 2 groups (n=29). All patients received antithyroid drugs orally and (or) Levothyroxine; they also received intravenous meprednisone (0.5 g) and cyclophosphamide (0.2 g) once a day for 3 days. After an interval of 4 days the administration of meprednisone and cyclophosphamide was repeated. All patients received a total of 3-6 times of treatment. Patients in group A were given prednisone and cyclophosphamide orally after immunosuppressants. Patients in group B were injected with Dexamethasone into thyroid after immunosuppressants. Results: Two patients withdrew from group A and one from group B. The therapeutic effect in group B was significantly better than that in group A (P<0.05). Compared with before treatment, the degrees of exophthalmos and exophthalmos activity were significantly lowered after treatment (P<0.05); the thyrotropin receptor antibodies (TRAb), thyroid peroxidase (TPOAb), peripheral blood NK cells, CD3+ T lymphocytes, and CD8+ T lymphocytes were significantly reduced after treatment (P<0.05); the ratio of CD4+/CD8+ was increased after the treatment (P<0.05). The degrees of exophthalmos, exophthalmos activity and levels of CD3+ T lymphocytes decreased more significantly in group B than in group A (P<0.05). The ratio of CD4+/CD8+ increased more significantly in group B than in group A(P<0.05). Before treatment the counts of CD4+ T lymphocytes were markedly different between the effective, moderately effective, and the ineffective group (P<0.05). Significant differences in TRAb, TPOAb, CD3+, CD8+ cells were found among the 3 groups after treatment. (P<0.05). CD4+ T lymphocytes and CD4+/CD8+ ratio were significantly higher after treatment compared with those before treatment (P<0.05). Significant differences in TRAb, CD4+, CD8+ T lymphocytes, CD4+/CD8+ ratio were found among 3 groups (P<0.05). Conclusion: Combination of meprednison and cyclophosphamide can relieve the abnormality of peripheral blood T cells in GO and has obvious therapeutic effect. Additional intrathyroid injection of dexamethasone may achieve even better outcome. The reduction of CD4+ T lymphocytes in peripheral blood of GO patients may indicate poor prognsis.

Relationship between the expression of TrkB and anoikis resistance in nasopharyngeal carcinoma line / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To study the regulation of anoikis by tyrosine kinase receptor B (TrkB) in human nasopharyngeal carcinoma lines. METHODS; Expression levels of TrkB and brain-derived neurotrophic factor (BDNF) were evaluated by RT-PCR and Western blot. Colony formation ability of C666-1 was observed in soft agar. Proliferation rate and apoptosis, that change in cells by treating the TrkB inhibitor K252a and specificity ligand BDNF respectively under suspension culture, were measured by cell counting kit-8 (CCK-8) assay and the flow cytometry assay. The expression change of TrkB, BDNF and phosphorylation of serine threonine kinase (p-Akt) were investigated by Western blot analysis.</p><p><b>RESULTS</b>TrkB and BDNF were identified in C666-1 cells. C666-1 cells could be decreased the proliferation of colony in soft agar by effect of K252a, but BDNF could make the colony prolific. K252a can inhibit the expression of TrkB in C666-1, and prevent p-Akt activation. And exogenous BDNF stimulated up-regulation TrkB and p-Akt, induced anoikis resistance.</p><p><b>CONCLUSION</b>TrkB inhibits anoikis in nasopharyngeal carcinoma cells. Inhibiton of TrkB by K252a can induce anoikis, and may prove particularly effective in treatment of nasopharyngeal carcinoma.</p>

Expression of recombined human immunoglobulin λ light chain 022 and TOM1 mRNA in omental adipose tissues of patients with type 2 diabetes and insulin resistance / 第二军医大学学报

Objective: To investigate the expression of recombined human immunoglobulin λ light chain 022 and TOM1 gene and to determine the protein expression of HSIGVL022 in omental adipose tissues of patients with type 2 diabetes and insulin resistance (T2DM-IR). Methods: Fat tissues from greater omentum of T2DM-IR patients and normal controls were obtained. The mRNA levels of recombined human immunoglobulin λ light chain 022 and TOM1 were measured by fluorescent quantitative RT-PCR; expression of HSIGVL022 protein was identified by immunohistochemistry. Results: The mRNA levels of HSIGVL022 and TOM1 in T2DM-IR patients were (34 140±6 160) copy/million house-keeping genes and (4 440±617) copy/ million housekeeping genes, respectively; those in control group were (5 930±661) copy/million house-keeping genes and (1 360±82) copy/million house-keeping genes, respectively. There were significant difference between the 2 groups (P<0.05). The mRNA level of HSIGVL022 was significantly higher than that of TOM1 (P<0.01) and was linearly correlated with homeostatic model assessment-insulin resistance (HOMA-IR) index(P<0.05). The positive rates of HSIGVL022 protein in T2DM-IR and control group were (12.43±2.41)% and (2.31±0.48)%, respectively; the strong positive rates were (6.62±1.69)% and (2.12± 0.34)%, respectively (P<0.05). Conclusion: Both HSIGVL022 and TOM1 are expressed in the fat tissues of greater omentum, with the level of HSIGVL022 higher than that of TOM1. The 2 genes are up-regulated in patients with insulin resistance and the HSIGVL022 protein increases correspondingly. The mRNA level of HSIGVL022 is linearly correlated with HOMA-IR index. The 2 genes are possibly related with insulin resistance in type 2 diabetes.

Expression of human rearranged immunoglobulin?light chain 022 in omental adipose tissues of type 2 diabetic patients / 中华内分泌代谢杂志

In adipose tissues from sreater omentum of patients with type 2 diabetes,the mRNA and protein expressions of human rearranged immunoglobulin?light chain (HSIGVL) 022 were measured by the fluorescent quantitative RT-PCR and immunohistochemistry respectively.The results showed that mRNA and protein levels of HSIGVL022 were up-regulated in patients with type 2 diabetes.The mRNA level of HSIGVL022 was linearly correlated with insulin resistance index,suggesting that this gene may play a role in the pathogenesis of insulin resistance and type 2 diabetes.