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Ehsan Hejazi Maryam Tavakoli Mahmood Jeddi-Tehrani Masoud Kimiagar Jalal Hejazi Mohammad Houshyari 《Nutrition and cancer》2017,69(7):1036-1042
Background: One major concern in the treatment of cancer patients during chemotherapy is drug resistance. Here we investigated the effects of soy isoflavone extracts alone or in combination with Docetaxel on the drug resistance, angiogenesis, apoptosis, and tumor volume in mouse 4T1 breast tumor model. Methods: Sixty female BALB/c mice were randomly divided into 4 groups: control, dietary soy isoflavone extract [Iso, 100 mg/kg diet (0.01%)], Docetaxel (10 mg/kg) injection, and the combination of dietary soy isoflavone extract and intravenous Docetaxel injection (Docetaxel + Iso). One week after the third injection, the breast tumors of eight mice from each group were excised to analyze NF-κBp65′ vascular endothelial growth factor receptor-2 (VEGFR2) and Pgp gene and protein expressions and the other seven mice were monitored for survival rate analysis until they died. Results: NF-κBp65 gene and protein expressions were significantly lower in the Docetaxel + Iso group in comparison with that of the Docetaxel group. VEGFR2 protein expression in the Docetaxel + Iso and Iso groups was significantly lower than that of the Docetaxel group. Conclusion: These findings may indicate that the combined use of isoflavone extracts together with chemotherapeutic agents has more efficient anti-carcinogenic effects than their individual use. 相似文献
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Can T1w/T2w ratio be used as a myelin‐specific measure in subcortical structures? Comparisons between FSE‐based T1w/T2w ratios,GRASE‐based T1w/T2w ratios and multi‐echo GRASE‐based myelin water fractions
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Md Nasir Uddin Teresa D. Figley Ruth Ann Marrie Chase R. Figley for the CCOMS Study Group 《NMR in biomedicine》2018,31(3)
Given the growing popularity of T1‐weighted/T2‐weighted (T1w/T2w) ratio measurements, the objective of the current study was to evaluate the concordance between T1w/T2w ratios obtained using conventional fast spin echo (FSE) versus combined gradient and spin echo (GRASE) sequences for T2w image acquisition, and to compare the resulting T1w/T2w ratios with histologically validated myelin water fraction (MWF) measurements in several subcortical brain structures. In order to compare these measurements across a relatively wide range of myelin concentrations, whole‐brain T1w magnetization prepared rapid acquisition gradient echo (MPRAGE), T2w FSE and three‐dimensional multi‐echo GRASE data were acquired from 10 participants with multiple sclerosis at 3 T. Then, after high‐dimensional, non‐linear warping, region of interest (ROI) analyses were performed to compare T1w/T2w ratios and MWF estimates (across participants and brain regions) in 11 bilateral white matter (WM) and four bilateral subcortical grey matter (SGM) structures extracted from the JHU_MNI_SS ‘Eve’ atlas. Although the GRASE sequence systematically underestimated T1w/T2w values compared to the FSE sequence (revealed by Bland–Altman and mountain plots), linear regressions across participants and ROIs revealed consistently high correlations between the two methods (r2 = 0.62 for all ROIs, r2 = 0.62 for WM structures and r2 = 0.73 for SGM structures). However, correlations between either FSE‐based or GRASE‐based T1w/T2w ratios and MWFs were extremely low in WM structures (FSE‐based, r2 = 0.000020; GRASE‐based, r2 = 0.0014), low across all ROIs (FSE‐based, r2 = 0.053; GRASE‐based, r2 = 0.029) and moderate in SGM structures (FSE‐based, r2 = 0.20; GRASE‐based, r2 = 0.17). Overall, our findings indicated a high degree of correlation (but not equivalence) between FSE‐based and GRASE‐based T1w/T2w ratios, and low correlations between T1w/T2w ratios and MWFs. This suggests that the two T1w/T2w ratio approaches measure similar facets of subcortical tissue microstructure, whereas T1w/T2w ratios and MWFs appear to be sensitized to different microstructural properties. On this basis, we conclude that multi‐echo GRASE sequences can be used in future studies to efficiently elucidate both general (T1w/T2w ratio) and myelin‐specific (MWF) tissue characteristics. 相似文献
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Mahmood Ahmadi-hamedani Zohreh Khaki Sadegh Rahbari Mahnaz A. Ahmadi-hamedani 《Comparative clinical pathology》2012,21(6):1179-1182
This study was conducted to measure selected hematological parameters in goats naturally infected with Anaplasma ovis. In this study 193 blood samples were collected from adult and young goats in north (Gonbad) and northeast (Mashhad) of Iran. Out of the 193 blood samples, 123 samples were positive (infected group) and 70 samples were negative (uninfected group) for A. ovis by polymerase chain reaction. Hematological analysis was carried out on 47 samples from the infected group and 37 samples from the uninfected group. Hematological analysis indicated significant decreases (P?<?0.01) in RBC counts, HCT values, and hemoglobin concentrations in the A. ovis-infected group of goats compared to the uninfected group (P?<?0.01). The mean corpuscular volume, mean corpuscular hemoglobin, WBC counts, lymphocytes, eosinophils, and monocytes in the infected group were lower but neutrophils were higher than in the uninfected group. These differences were not statistically significant (P?>?0.05). The result from this study revealed that A. ovis infection in goats is associated with marked changes in hematological parameters. 相似文献
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