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1.
Asian Journal of Andrology ; (6): 25-33, 2023.
Artigo em Inglês | WPRIM | ID: wpr-1009810

RESUMO

The sperm DNA fragmentation index (DFI) is a metric used to assess DNA fragmentation within sperm. During in vitro fertilization-embryo transfer (IVF-ET), high sperm DFI can lead to a low fertilization rate, poor embryo development, early miscarriage, etc. A kinase anchoring protein (AKAP) is a scaffold protein that can bind protein kinase A (PKA) to subcellular sites of specific substrates and protects the biophosphorylation reaction. Sperm protein antigen 17 (SPA17) can also bind to AKAP. This study intends to explore the reason for the decreased fertilization rate observed in high sperm DFI (H-DFI) patients during IVF-ET. In addition, the study investigates the expression of AKAP, protein kinase A regulatory subunit (PKARII), and SPA17 between H-DFI and low sperm DFI (L-DFI) patients. SPA17 at the transcriptional level is abnormal, the translational level increases in H-DFI patients, and the expression of AKAP4/PKARII protein decreases. H2O2 has been used to simulate oxidative stress damage to spermatozoa during the formation of sperm DFI. It indicates that H2O2 increases the expression of sperm SPA17 protein and suppresses AKAP4/PKARII protein expression. These processes inhibit sperm capacitation and reduce acrosomal reactions. Embryo culture data and IVF outcomes have been documented. The H-DFI group has a lower fertilization rate. Therefore, the results indicate that the possible causes for the decreased fertilization rate in the H-DFI patients have included loss of sperm AKAP4/PKARII proteins, blocked sperm capacitation, and reduced occurrence of acrosome reaction.

2.
Journal of Medical Biomechanics ; (6): E311-E317, 2015.
Artigo em Chinês | WPRIM | ID: wpr-804422

RESUMO

Objective To study the effects of radiation sensitivity coefficient, frequency of treatment and mature age of tumor cells on therapeutic efficacy by numerical simulation. Methods A hybrid mathematical model for the growth of solid tumor under radiotherapy was established, with considering the influence of both tumor microenvironment (including oxygen, extracellular matrix and matrix-degrading enzymes) and tumor activities (including proliferation, apoptosis and adhesion) on tumor growth. The linear quadratic model was also introduced to depict tumor response to radiotherapy. The progresses of tumor growth under different conditions were simulated to assess the therapeutic efficacy. Results The therapeutic efficacy was better when the radiation sensitivity coefficient and mature age of tumor cells increased. When the total amount of the radiation dose was the same, the effects of treatments seemed no difference either with high frequency or low frequency. Conclusions The simulation results are consistent with the clinical results, which can provide a new method for the theoretical and clinical research on tumor radiotherapy.

3.
Journal of Medical Biomechanics ; (6): E456-E459, 2012.
Artigo em Chinês | WPRIM | ID: wpr-804007

RESUMO

Objective To make a quantitative research on the vertical force homogeneity of Yizhichan manipulation and look for the quantitative index and reference value which can describe the force homogeneity of Yizhichan manipulation effectively. Methods After the force homogeneity was described mathematically, the vertical force signals from Yizhichan manipulation operated by 5 experts, 5 skilled doctors and 5 beginners were measured and analyzed, respectively. Results The period homogeneities and the waveform homogeneities were obtained. No significant differences were found in the period homogeneities among the three groups, but significant differences appeared in waveform homogeneities between the beginner and expert group or the beginner and skilled doctor group. Conclusions The waveform homogeneities are more suitable for evaluating the vertical force homogeneity of Yizhichan manipulation by different operators, and 0.927 can be used as a reference value to evaluate the vertical force homogeneity of the operator.

4.
Journal of Medical Biomechanics ; (6): E439-E443, 2010.
Artigo em Chinês | WPRIM | ID: wpr-803700

RESUMO

Objective To analyze the energy of rolling manipulation in different frequency bands and find the features of rolling manipulation dynamics. MethodThe force signals of rolling manipulation of six experts and six beginners were measured and divided into different frequency bands by wavelet transform to calculate the energy. Through statistical analysis, 18 characteristic quantities of horizontal force or vertical force were created and the overall evaluation coefficient R was proposed. ResultsAbout 70% of experts’ rolling manipulation energy was found in 0~0.406 25 Hz and about 20% energy in 1.625~3.25 Hz. The overall evaluation coefficient R of 6 experts was over 0.70, while R of beginners was below 0.70, which showed the difference was significant. ConclusionsThe energy distribution of rolling manipulation reflects the characteristics of softness and periodicity. If the rolling manipulation is in accordance with the manipulative requirement and the overall evaluation coefficients R is over 0.70, it could be said that the operator masters the rolling manipulation well.

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