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Objective:To establish Wistar rat models of acute radiation esophagitis, and observe the histopathological changes at different time points after modeling.Methods:Wistar rats were locally irradiated with different doses of 6 MV X-rays, and the rats were sacrificed on the 3 rd, 5 th, 7 th, and 14 th days after irradiation. The full-length esophagus tissue was taken for paraffin embedding, sectioning, and hematoxylin and eosin (HE) staining for pathological assessment. The pathological changes of the esophagus of the rats were observed at the 3 rd, 5 th, 7 th, and 14 th days after 25 Gy and 30 Gy irradiation. The changes of daily dietary intake of rats in different irradiation groups within 1-2 weeks after radiation exposure were observed. Results:No rat died in two groups after being irradiated with 25 Gy and 30 Gy rays. All the rats in the 30 Gy group had esophagus injury. On the 7 th day, the degree of injury was the most serious, with a pathological score of 5.00±0.75 and a food intake of 0 g. On the 14 th day, the degree of injury was relieved, and the food intake was restored to the level before irradiation. Conclusions:The Wistar rat model of acute radiation esophagitis can be established by a single dose of 6 MV X-ray 30 Gy irradiation to the esophagus. The 7 th day after irradiation is an ideal observation time for the acute injury phase, which is gradually alleviated after the 7 th day. The time can be chosen from 7-14 days after irradiation as the observation point for the healing repair phase.
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The enrichment of tyrosine phosphorylation sites plays an important role in the study of tyrosine phosphoproteomics and the commonly used enrichment methods are antibody affinity enrichment and SH2 superbinder enrichment. In addition, in order to achieve large-scale identification of tyrosine phosphorylation sites, biological mass spectrometry and bioinformatics have been applied in tyrosine phosphoproteomics. In-depth coverage research of tyrosine phosphoproteomics, revealing the dysregulated kinases in cancer process, may help us understanding the occurrence and development process of cancer. According to literature reports, three quarters of the oncogenes are tyrosine kinase genes. Therefore, tyrosine kinase inhibitors have received more and more attention as anticancer drugs. The application of tyrosine phosphoproteomics technology can identify tyrosine kinases related to cancer and other major diseases, so as to help finding tyrosine kinase inhibitors. In short, tyrosine phosphoproteomics technology can be applied in biomedical fields such as tyrosine kinase identification, tyrosine kinase inhibitor research, and tyrosine phosphorylation signal pathway research.
Subject(s)
Biomedical Research , Mass Spectrometry , Phosphorylation , Proteomics , Tyrosine/metabolismABSTRACT
Objective:To confirm the Sigma N transcription factor activity of a gene product encoded by LA2404 gene of Leptospira interrogans ( L. interrogans) and to identify the target genes of Sigma N signaling system. Methods:L. interrogans LA2404 gene and its regulated target genes were predicted using bioinformatic analysis according to the promoter sequence signature in Sigma N-regulated genes. A LA2404 gene-knockout (ΔLA2404) strain of L. interrogans was constructed based on homologous sequence recombinant of suicide plasmid. Real-time fluorescent quantitative RT-PCR (qRT-PCR) was used to detect the changes in the expression of target genes at mRNA level in the ΔLA2404 mutant. A prokaryotic expression system for LA2404 gene was established and the target recombinant protein rSigma N was extracted by Ni-NTA affinity chromatography. Gel electrophoresis mobility shift assay (EMSA) was used to screen out the target genes regulated by rSigma N. Results:Pathogenic L. interrogans serogroup Icterohaemorrhagiae serovar Lai strain Lai carried one Sigma N gene and 22 Sigma N promoter sequence-containing target genes. Qualitative examination of the ΔLA2404 mutant by microscopy revealed no defect in motility and appearance. Expression of LA1188, LA2306, LA3426, LA1968, LA1313, LA3806 and LA0773 genes at mRNA level in the ΔLA2404 mutant was significantly down-regulated ( P<0.05), but no significant changes in the expression of other target genes at mRNA level were detected. EMSA results confirmed that rSigma N could bind to the promotor sequences of the target genes mentioned above. Conclusions:Sigma N transcription factor was encoded by LA2404 gene. LA1188, LA2306, LA3426, LA1968, LA1313, LA3806 and LA0773 genes contained Sigma N promoter sequence and the expression of them was regulated by Sigma N signaling system.
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Objective To investigate the effects of JNK inhibition on insulin signaling pathway. Methods HepG2 cells were treated with different kinds of JNK inhibitors for 12 h, and then the cells were treated with 10 nmol/L insulin for 5 min to stimulate insulin signaling pathway. Mitogen-activated protein kinases ( MAPK ) and insulin signaling pathways were analyzed by Western blot using the total cell lysates. Results JNK activity was significantly inhibited by JNK inhibitor JNKi-Ⅷand results showed that JNKi-Ⅷtreatment could reduce insulin signaling pathway in a dose-dependent manner. Furthermore, other JNK inhibitors including JNKi-Ⅴ, JNKi-Ⅲ, and SP600125 blocked JNK activity in HepG2 cells. Similar to JNKi-Ⅷ, these JNK inhibitors also impaired insulin signaling transduction in a dose-dependent manner. Conclusion In HepG2 hepatocytes, JNK activity inhibition blocks insulin signaling transduction.
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Objective To determine whether Auto-Planning-based volumetric modulated radiotherapy(Auto-VMAT)planning can improve planning efficiency without compromising plan quality compared with current manual trial-and-error-based volumetric modulated arc therapy(Manual-VMAT) planning for patients with rectal cancer. Methods Ten patients with stage Ⅱ-Ⅲ rectal cancer who underwent Dixon surgery were enrolled as subjects. The Pinnacle 9.10 planning system was used to design Manual-VMAT and Auto-VMAT plans. Dose distribution,homogeneity index(HI),conformity index(CI), D meanvalues of different organs at risk or dose-volume histogram of regions of interest,total planning time, and manual planning time were compared between the two plans. The differences were analyzed by paired t test. Results Dosimetric prescriptions were achieved in both plans. There were no significant differences in HI or CI between the Auto-VMAT plans and the Manual-VMAT plans(0.058 vs. 0.058, P=0.972;0.921 vs. 0.940,P=0.115). Compared with the Manual-VMAT plans,the V 40,D mean,and D 50%of the bladder were significantly reduced by 25.6%, 11.5%, and 8.9%, respectively, in the Auto-VMAT plans(P=0.004,0.016,0.001);the V 40,D mean,and D 50%of the small intestine were also significantly reduced by 12.1%,5.4%,and 6.8%,respectively,in the Auto-VMAT plans(P=0.023,0.001,0.001);the V 30, D mean,and D 50%of the left and right femoral heads were slightly reduced in the Auto-VMAT plans. The Auto-VMAT plans had significantly longer total planning time but significantly shorter manual planning time than the Manual-VMAT plans(50.38 vs. 36.81 min, P= 0.000;4.47 vs. 16.94 min, P= 0.000). Conclusions Compared with the Manual-VMAT plans, the Auto-VMAT plans have substantially shorter manual planning time and improved planning efficiency.
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Background and purpose:Radiotherapy has been the preferred method for the treatment of naso-pharyngeal carcinoma (NPC). The aim of this paper was to compare the dosimetric differences in target volume and organ at risk between simpliifed intensity-modulated radiation therapy (sIMRT) and intensity-modulated radiation therapy (IMRT) in nasopharyngeal carcinoma.Methods:Treatment plans for ten NPC cases were designed with the same dose prescription and objective by means of IMRT and sIMRT respectively. Compare:(1) Plan dosimetric dis-tribution, conformity index (CI) and homogeneity index (HI) of the targets, the dosimetric parameters of organ at risk (OAR); (2)The total monitor units (MU) and the total segments.Results:The CI and HI of the planning gross tumor volume(PGTV) were 0.647 and 0.057 (IMRT), 0.633 and 0.071 (sIMRT), respectively (t=2.14,P=0.062;t=-6.21, P=0.000). Compared to IMRT, sIMRT had less inferior target homogeneity. However both treatment plans could achieve the clinical dosimetric demands. There was no signiifcant difference between IMRT and sIMRT in protecting OAR (t=-0.51-2.22,P=0.053-0.621). The sIMRT plan was better than IMRT plan in total MU and total segments. Conclusion:sIMRT is slightly inferior to IMRT in terms of target homogeneity, with similar target conformity and OAR dosimetric parameters. The sIMRT plan can reduce total monitor units and total segments. Thus it provides a clinical solution with high effciency for radiotherapy center with a large number of patients.
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Discrimination of abnormal images from the numerous wireless capsule endoscope (WCE) video sequence images is laborious and time-consuming, so that a computer-based automatic image recognition system is desired for this task. We propose an algorithm to allow feature extraction from each image channel and decision fusion using multiple BP neural networks. The algorithm was tested and the results demonstrated its high efficiency and accuracy in identification of abnormalities in the WCE images.