Δευτέρα, 5 Μαρτίου 2018

Researching of tritium speciation in soils of “Balapan” site

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Publication date: Available online 5 March 2018
Source:Journal of Environmental Radioactivity
Author(s): Z.B. Serzhanova, A.K. Aidarkhanova, S.N. Lukashenko, O.N. Lyakhova, L.V. Timonova, A.M. Raimkanova
Speciation of tritium (3Н) in soils from the "Balapan" site in Semipalatinsk are presented in this study. Three interrelated objects were chosen for further study: "Atomic" lake, the Shagan River and an external reservoir. The main speciation forms of 3Н in soil were: 3Н in surface-adsorbed water, 3Н in interlayer water, hydroxylic 3Н, organically bound 3Н and crystalline-bound 3Н.Results will allow an estimation of contamination mechanism to be made, and will also allow the potential for migration and bioavailability of 3Н to be assessed.



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Antitumor and radiosensitizing effects of SKLB-163, a novel benzothiazole-2-thiol derivative, on nasopharyngeal carcinoma by affecting the RhoGDI/JNK-1 signaling pathway

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Publication date: Available online 5 March 2018
Source:Radiotherapy and Oncology
Author(s): Jinlan He, Lei Cai, Ye Chen, Yan He, Ming Wang, Jie Tang, Hui Guan, Jingjing Wang, Xingchen Peng
Background and purposeSKLB-163 is a novel benzothiazole-2-thiol derivative with antitumor activities. This study investigated the effects of SKLB-163 on nasopharyngeal carcinoma (NPC) and its mechanisms.Materials and methodsRho GDP-dissociation inhibitor (RhoGDI) expression was examined in NPC cell lines by western blot. Effects of SKLB-163 on proliferation, migration and radiosensitivity were assessed by MTT, wound healing and colony formation assays in vitro. Anti-tumor and anti-metastatic effects, and radiosensitizing effects of SKLB-163 were evaluated in a NPC lung metastatic nude mouse model and a subcutaneous xenograft mouse model. Effects of SKLB-163 on proliferation and apoptosis were assessed by PCNA immunohistochemistry and TUNEL assay in vivo. Key molecules in RhoGDI/c-Jun N-terminal kinases-1 (JNK-1) pathway were examined by western blot.ResultsRhoGDI was up-regulated in NPC cell lines. SKLB-163 inhibited proliferation and migration, and increased radiosensitivity of NPC cells. SKLB-163 inhibited tumor growth and metastases, and sensitized tumor to irradiation. The radiosensitizing effects were correlated with induction of apoptosis and suppression of proliferation. The molecular mechanism was the down-regulation of RhoGDI and activation of JNK-1 signaling, and the subsequent activation of caspase-3 and the decrease in phosphorylated AKT.ConclusionsSKLB-163 shows strong anti-tumor activities against NPC and sensitizes NPC to irradiation by affecting the RhoGDI/JNK-1 pathway.



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4π plan optimization for cortical-sparing brain radiotherapy

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Publication date: Available online 5 March 2018
Source:Radiotherapy and Oncology
Author(s): Vyacheslav L. Murzin, Kaley Woods, Vitali Moiseenko, Roshan Karunamuni, Kathryn R. Tringale, Tyler M. Seibert, Michael J. Connor, Daniel R. Simpson, Ke Sheng, Jona A. Hattangadi-Gluth
Background and purposeIncidental irradiation of normal brain tissue during radiotherapy is linked to cognitive decline, and may be mediated by damage to healthy cortex. Non-coplanar techniques may be used for cortical sparing. We compared normal brain sparing and probability of cortical atrophy using 4π radiation therapy planning vs. standard fixed gantry intensity-modulated radiotherapy (IMRT).Material and methodsPlans from previously irradiated brain tumor patients ("original IMRT", n = 13) were re-planned to spare cortex using both 4π optimization ("4π") and IMRT optimization ("optimized IMRT"). Homogeneity index (HI), gradient measure, doses to cortex and white matter (excluding tumor), brainstem, optics, and hippocampus were compared with matching PTV coverage. Probability of three grades of post-treatment cortical atrophy was modeled based on previously established dose response curves.ResultsWith matching PTV coverage, 4π significantly improved HI by 27% (p = 0.005) and gradient measure by 8% (p = 0.001) compared with optimized IMRT. 4π optimization reduced mean and equivalent uniform doses (EUD) to all standard OARs, with 14–15% reduction in hippocampal EUD (p ≤ 0.003) compared with the other two plans. 4π significantly reduced dose to fractional cortical volumes (V50, V40 and V30) compared with the original IMRT plans, and reduced cortical V30 by 7% (p = 0.008) compared with optimized IMRT. White matter EUD, mean dose, and fractional volumes V50, V40 and V30 were also significantly lower with 4π (p ≤ 0.001). With 4π, probability of grade 1, 2 and 3 cortical atrophy decreased by 12%, 21% and 26% compared with original IMRT and by 8%, 14% and 3% compared with optimized IMRT, respectively (p ≤ 0.001).Conclusions4π radiotherapy significantly improved cortical sparing and reduced doses to standard brain OARs, white matter, and the hippocampus. This was achieved with superior PTV dose homogeneity. Such sparing could reduce the probability of cortical atrophy that may lead to cognitive decline.



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4π plan optimization for cortical-sparing brain radiotherapy

Incidental irradiation of normal brain tissue during radiotherapy is linked to cognitive decline, and may be mediated by damage to healthy cortex. Non-coplanar techniques may be used for cortical sparing. We compared normal brain sparing and probability of cortical atrophy using 4π radiation therapy planning vs. standard fixed gantry intensity-modulated radiotherapy (IMRT).

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Antitumor and radiosensitizing effects of SKLB-163, a novel benzothiazole-2-thiol derivative, on nasopharyngeal carcinoma by affecting the RhoGDI/JNK-1 signaling pathway

SKLB-163 is a novel benzothiazole-2-thiol derivative with antitumor activities. This study investigated the effects of SKLB-163 on nasopharyngeal carcinoma (NPC) and its mechanisms.

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Vertical and sagittal combinations of concha bullosa media and paradoxical middle turbinate.

Vertical and sagittal combinations of concha bullosa media and paradoxical middle turbinate.

Surg Radiol Anat. 2018 Mar 03;:

Authors: Sava CJ, Rusu MC, Săndulescu M, Dincă D

Abstract
Common anatomic variants of the middle nasal turbinate include its pneumatization (i.e. concha bullosa media) and its paradoxical curvature. We report here two cases of differently combined variations of the middle turbinate which were documented in cone beam computed tomography (CBCT). The first report presents the vertical combination of a double or septated lamellar concha bullosa with the paradoxical curvature of middle turbinate. This combined variant associated (coincidental findings): ipsilateral paradoxical superior turbinate and contralateral paradoxical middle turbinate, concha bullosa superior and concha bullosa suprema. In the second case was found the sagittal combination of successive anterior concha bullosa media and posterior paradoxical curvature of the middle turbinate. An ethmoidal sinolith was found embedded in lamella basalis. The contralateral superior turbinate was pneumatized. These rare findings demonstrate that sound knowledge of possible anatomical variations, supported by a complete use of the tools available for the CBCT documentation of cases, is able to enrich the picture of human anatomic variations, with a direct impact on clinical and surgical practice. The septa-containing lamellar concha bullosa and paradoxical middle concha combination is a variation that affects surgical practice.

PMID: 29502247 [PubMed - as supplied by publisher]



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Dynamic susceptibility contrast (DSC) perfusion MRI in differential diagnosis between radionecrosis and neoangiogenesis in cerebral metastases using rCBV, rCBF and K2

Abstract

Introduction

Distinction between treatment-related changes and tumour recurrence in patients who have received radiation treatment for brain metastases can be difficult on conventional MRI. In this study, we investigated the ability of dynamic susceptibility contrast (DSC) perfusion in differentiating necrotic changes from pathological angiogenesis and compared measurements of relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF) and K2, using a dedicated software.

Methods

Twenty-nine patients with secondary brain tumors were included in this retrospective study and underwent DSC perfusion MRI with a 3-month follow-up imaging after chemo- or radiation-therapy. Region-of-interests were drawn around the contrast enhancing lesions and measurements of rCBV, rCBF and K2 were performed in all patients. Based on subsequent histological examination or clinico-radiological follow-up, the cohort was divided in two groups: recurrent disease and stable disease. Differences between the two groups were analyzed using the Student's t test. Sensitivity, specificity and diagnostic accuracy of rCBV measurements were analyzed considering three different cut-off values.

Results

Between patients with and without disease, only rCBV and rCBF values were significant (p < 0.05). The only cut-off value giving the best diagnostic accuracy of 100% was rCBV = 2.1 (sensitivity = 100%; specificity = 100%). Patients with tumor recurrence showed a higher mean value of rCBV (mean = 4.28, standard deviation = 2.09) than patients with necrotic-related changes (mean = 0.77, standard deviation = 0.44).

Conclusion

DSC-MRI appears a clinically useful method to differentiate between tumor recurrence, tumor necrosis and pseudoprogression in patients treated for cerebral metastases. Relative CBV using a cut-off value of 2.1 proved to be the most accurate and reliable parameter.



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Eigenfactor score and alternative bibliometrics surpass the impact factor in a 2-years ahead annual-citation calculation: a linear mixed design model analysis of Radiology, Nuclear Medicine and Medical Imaging journals

Abstract

Introduction

Because we believe the journal selection before a manuscript submission deserves further investigation in each medical specialty, we aimed to evaluate the predictive ability of seven bibliometrics in the Radiology, Nuclear Medicine and Medical Imaging category of the Web of Knowledge to calculate total citations over a 7-year period.

Methods

A linear mixed effects design using random slopes and intercepts were performed on bibliometrics corresponding to 124 journals from 2007 to 2011, with their corresponding citations from 2009 to 2013, which appeared in the Journal Citations Report Science Edition.

Results

The Eigenfactor Score, Article Influence Score, Cited Half-life, 5-years impact factor and Number of Articles are significant predictors of 2-year-ahead total citations (p ≤ 0.010 for all variables). The impact factor and Immediacy Index are not significant predictors. There was a significant global effect size (R2 = 0.934; p < 0.001), which yielded a total variance of 93.4%.

Conclusions

Our findings support researchers' decision to stop the misuse of IF alone to evaluate journals. Radiologists and other researchers should review journal's bibliometrics for their decision-making during the manuscript submission phase. A re-ranking of journals using Eigenfactor Score, Article Influence Score, and Cited Half-life provides a better assessment of their significance and importance in particular disciplines.



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Multiparametric MR imaging detects therapy efficacy of radioactive seeds brachytherapy in pancreatic ductal adenocarcinoma xenografts

Abstract

Objective

To investigate the therapeutic efficacy of Iodine-125 (125I) seeds brachytherapy to pancreatic ductal adenocarcinoma (PDAC) xenografts via multiparametric magnetic resonance imaging (MRI) analysis.

Materials and methods

Twenty mice were implanted subcutaneously with SW-1990 PDAC xenografts. The tumor-bearing mice were randomly divided into 125I seeds group (n = 10) and blank control group (n = 10). Treatment response was monitored by diffusion-weighted magnetic resonance imaging (DW-MRI) and dynamic contrast-enhanced MRI (DCE-MRI) obtained 1 day before, 14 and 60 days after treatment. Imaging results were correlated with histopathology.

Results

125I seeds brachytherapy resulted in a significant increase in mean tumor apparent diffusion coefficient (ADC) values compared to the control at 14 and 60 days after treatment (p < 0.05). DCE-MRI showed a significant decrease in the perfusion parameters including Ktrans and Kep (p < 0.05). The mean ADCs within the peripheral region of the tumors were linearly proportional to the mean apoptotic cell density (p = 0.015; Spearman's coefficient = 0.945). The Ktrans and Kep were linearly proportional to microvessel density (MVD) (p = 0.043, 0.047; Spearman's coefficient = 0.891, 0.884).

Conclusion

125I seeds brachytherapy leads to effective inhibition of PDAC cell proliferation, higher degree of necrosis and necroptosis, and lower MVD. Both DW-MRI and DCE-MRI are feasible to monitor a response to 125I seeds brachytherapy in the PDAC xenografts. This paper shows an original project concerning about a possible palliative treatment not only in a murine model (preclinical setting) but also in humans.



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