BACKGROUND: Because of complicated physiological environment and difficulty to control experimental conditions, it is difficult to get satisfactory results from in vivo studies of cell mechanics.OBJECTIVE: To study the action and mechanism of p38MAPK signaling pathways on myoblast apoptosis based on successful construction of in vitro mechanical stimulation models.METHODS: The C2C12 cells cultured in vitro were divided into control group and SB203580 treatment group. Cyclic tensile stress was applied on the C2C12 myoblast cells for 0, 6, 12 and 24 hours in each group. The Flexcell Strain Unit-5000T was used to expose C2C12 myoblast cell to an equiaxial cyclic of 15% magnitude and a frequency of 10 cycles/min, each cycle including the 3 s stretch and 3 s relaxation. Hoechst 33258 fluorescent staining and optical microscope were used to detect cell apoptosis. RT-PCR, flow cytometric analysis were used to observe the apoptosis of C2C12 myoblast cells and Western blotting were used to detect the activity of p38MAPK and p-p38MAPK. RESULTS AND CONCLUSION: The optical microscope tested the change in the morphology. Hoechst 33258 staining showed that after treatment with cyclic stress, the cell took the typical appearance of apoptosis with chromatin condensation and apoptotic bodies. RT-PCR and flow cytometry showed that with the extension of time the rate of the apoptosis of C2C12 myoblast cell increased. And cells imposed SB203580 before imposing cyclical tensile stress, the results showed that the apoptosis was markedly affected, and the p-p38MAPK expression declined apparently. These findings demonstrate that p38MAPK signaling pathways in stress mediated into C2C12 myoblast cell apoptosis plays an important role.

Objective To investigate the expressions of carbohydrate antigen 19-9(CA19-9), carbohydrate antigen 15-3(CA15-3) and carbohydrate antigen 125(CA125) and their clinical significance in papillary thyroid carcinoma (PTC). Methods The expressions of CA19-9, CA15-3 and CA125 were detected by immunohistochemical MaxVision method in 80 cases of PTC and 80 cases of benign thyroid lesions (BTL), including 34 cases of nodular goiter, 26 cases of Hashimoto's thyroiditis and 20 cases of follicular adenoma. The relationship between expressions of CA19-9, CA15-3 and CA125 and the clinical pathological characteristics were analyzed. Results The expression rates of CA19-9, CA15-3 and CA125 in 80 cases of PTC were 85%, 100%and 43.8%respectively, compared with BTL, the difference was statistically significant (P < 0.01). There was no significant correlation between expressions of CA19-9, CA15-3 and CA125 and age, gender, number and diameter of tumor nodules, lymph node metastasis, and TNM staging (P > 0.05). The sensitivity of CA19-9, CA15-3 and CA125 in the differential diagnosis of PTC and BTL were 85%, 100% and 43.8% respectively, and the specificity were 91.3%, 36.3%and 91.3%, respectively. Conclusion The expressions of CA19-9, CA153 and CA125 are helpful for the differential diagnosis of PTC and BTL.

Congenital heart defects(CHD) are the most common birth defects in China. However, the etiology of most CHD remains unclear. In recent years, with the development of molecular diagnostic techniques, some researchers began to pay attention to microRNA in CNVs detected in CHD children. However, microRNA in CNVs(miRNA-CNVs) as a genetic mechanism in CHD is not known with certainty. So the research progress of the relationship between microRNA, CNVs, miRNA-CNVs and CHD were summarized in this paper.

Objective To investigate the difference of iNOS and NQO1 in breast cancer with different mo-lecular subtypes and the correlation between clinical parameters,and to explore the clinical treatment of breast can-cer. Methods The data on 100 patients with breast cancer who had undergone modified radical mastectomy was retrospectively reviewed.Expressions of iNOS and NQO1 were detected by immunohistochemistry.Numeration data was processed using χ2test or Fisher′s exact test.Spearman correlation was applied to analyze different clinical mo-lecular pathological features.Results NQO1 expression was correlated with TNM staging and lymph node metasta-sis(χ2=6.603,4.938,P<0.05),and the expression rate of NQO1 in overexpressing of HER-2 was higher than that in type luminal A(χ2=8.341,P < 0.008). Expression of iNOS was related to expression of Ki-67,stage of TNM and lymph node metastasis(χ2=5.243,8.157,and 5.929,P<0.05),the expression rate of iNOS in lumi-nal A was significantly lower than that in type luminal B(χ2=7.990,P<0.008).Conclusions The expression of NQO1 and iNOS may be involved the process of oxidative stress associated with breast cancer,and it plays an im-portant role in the development of breast cancer. Different molecular level of oxidative stress between the types of breast cancer may be different,whose molecular mechanism needs to be further studied.

Objective To observe potential effect of radon hot springs on the changes of cell cycle and its regulatory proteins of CDK1,CDK2,CDK4,CDK6,CyclinD1,CyclinE1,WEE1,CDC25A in the peripheral blood lymphocytes of residents.Methods A random sampling method was used to persons 46 persons from the residents around radon hot spring in Wentang town,and 39 persons were selected from the control area without radon exposure.Flow cytometry was used to detect the changes of cell cycle and the expressions of cell cycle-related regulatory proteins.Multiple linear regression method was used to analyze the relationship between the expressions of cell cycle regulatory proteins and radon exposure.Results The percentages of cells at G0/G1 phase and S phase in lymphocytes were different in the two groups (t =2.250,-2.382,P ＜ 0.05).The expression levels of CDK1,CDK6 and CyclinE1 in the peripheral blood lymphocytes of radon hot spring group were significantly decreased (t =4.770,11.419,5.238,P ＜ 0.05) and negatively correlated with radon exposure (t =-5.097,-11.128,-5.117,P ＜0.05).The expression levels of CDK2,CDK4,CyclinD1,WEE1 and CDC25A in the peripheral blood lymphocytes of radon hot spring group were increased but not significantly(P ＞ 0.05).Conclusions The incidences of a higher ratio of S-phase cells and lower expression levels of CDK1,CDK6 and CyclinE1 in the peripheral blood lymphocytes of residents in Wentang town may be related to long-term radon exposure.