Objective To perfect gene profile expressed in pre-implantation embryos. Methods Using nested RT-PCR to investigate the expression of seven imprinted genes: P57~ KIP2, LIT1, TSSC3, GRB10, PEG3, ARHI, and ZAC1 in human oocytes and pre-implantation embryos. Results Transcripts of P57~ KIP2 and ZAC1 were detected in human oocytes and at all stages of pre-implantation; LIT1 was expressed only in stages of 8-cell and blastocyst; transcripts of TSSC3 could not be detected; GRB10 mRNA could be detected in oocytes and pre-implantation embryos except for 2-cell embryo; ARHI was expressed in oocytes and 2,8-cell embryos and blastocyst; Peg3 mRNA existed in 4,8-cell embryos and blastocyst. Conclusion Except for TSSC3, transcripts of the other six imprinted genes are detected in human pre-implantation development, which are helpful for pre-implantation diagnosis of imprinted diseases, and provide the theoretical basis for understanding the correlation among assisted reproductive technology, genetic imprinted diseases and tumor.

A three-phase depletion/repletion/depletion feeding study was designed to investigate the changes of Se levels and glutathione peroxidase (GSH-Px) activities in tissues and blood in rats fed for 6 weeks low-Se diet (6 ppb Se) from a Keshan disease area during the supplementations of Se as Ziyang high-Se wheat (1.175 ppm Se) or sodium selenite (dietary Se 219 and 223 ppb respectively) and after the supplements were discontinued, and to evaluate the relative bioavailability of Se in the wheat. The resalts showed that the average bioavailability of Se in high-Se wheat derived from the values at wk 2, 4 and 6 of supplement was close to that in selenite when plasma, erythrocyte, kidney, liver and cardiac Se contents were used as the response criteria, the relative bioavailabilities being 98%, 104%,100%,96% and 101% (sodium selenite = 100%) respectively. The bioavailability was lower for Se in high-Se wheat (70% or 90%) than for selenite when estimated by erythro-cyte or cardiac GSH-Px activities. However, the bioavailabilities of high-Se wheat Se in various tissues were not all the same at different stages of supplement. In addition, the effect of Se in high-Se wheat in maintaining either Se levels in heart, liver and erythrocyte or GSH-Px activity in heart was superior to that of selenite 3 weeks after the Se supplements were withdrawn.

Acetylation ; Animals ; Humans ; Phosphorylation ; Tumor Suppressor Protein p53 ; chemistry ; genetics ; metabolism ; physiology

0.05).There were more polycystic ovary (PCO) and (or) polycystic ovarian syndrome (PCOS) patients,more basal antra] follicles,longer duration of Gn stimulation (range 16-33 days),higher Gn dose,lower serum peak estradiol (E_2) level,fewer oocytes,fewer embryos transferred,in group 1 compared with group 2 (P

Objective To propose a treatment planning optimization algorithm which can make full use of OAR dose distribution prediction meanwhile improving the output planning quality as much as possible.Methods We had reformulated an FMO function under the guidance of dose distribution prediction and also integrated equivalent uniform dose (gEUD) based on the consideration of prediction uncertainty,for providing optimal solution.Performance of the method was evaluated by comparing the optimized IMRT plan quality of 8 cervical cancers in the term of DVH curves,dose distribution and dosimetric endpoints with the original ones.Results The proposed method had a feasible,fast solution.Compared with original plan,its output plan had better plan quality in better dose homogeneity,less hot spot and further dose sparing for OARs.V30,V45 of rectum was decreased by (6.60±3.53)％ and (17.03±7.44)％,respectively,with the statistically significant difference (t=-4.954,-6.055,P＜0.05).V30,V45 of bladder was decreased by (14.74 ± 5.61) ％ and (14.99 ± 4.53) ％,respectively,with the statistically significant difference (t=-6.945,-8.759,P＜0.05).Conclusions We have successfully developed a predicted dose distribution and equivalent uniform dose-based planning optimization method,which is able to make good use of 3D dose prediction and ensure the output plan quality for intensity modulated radiation therapy.

Objective To establish a three-dimensional (3D) dose prediction model,which can predict multiple organs simultaneously in a single model and automatically learn the effect of the geometric anatomical structure on dose distribution.Methods Clinical radiotherapy plans of patients diagnosed with the same type of tumors were collected and retrospectively analyzed.For every plan,each organs at risk (OAR) voxel was regarded as the study sample and its deposited dose was considered as the dosimetric feature.A regularized multi-task learning method than could learn the relationship among different tasks was employed to establish the relationship matrix among tasks and the correlation between geometric structure and dose distribution among organs.In this experiment,the spinal cord,brainstem and bilateral parotids involved in the intensity-modulated radiotherapy (IMRT) plan of 15 nasopharyngeal cancer patients were utilized to establish the multi-organ prediction model.The relative percentage error between the predicted dose of voxel and the clinical planning dose was calculated to assess the feasibility of the model.Results Ten cases receiving IMRT plans were utilized as the training data,and the remaining five cases were used as the test data.The test results demonstrated a higher prediction accuracy and less data demand.And the average voxel dose errors among the spinal cord,brainstem and the left and right parotids were (2.01±0.02)％,(2.65± 0.02) ％,(2.45± 0.02) ％ and (2.55± 0.02) ％,respectively.Conclusion The proposed model can accurately predict the dose of multiple organs in a single model and avoid the establishment of multiple single-organ prediction models,laying a solid foundation for patient-specific plan quality control and knowledge-based treatment planning.