2,595 research outputs found
Radiation therapy in the management of malignant gliomas
Several randomized trials have provided evidence supporting the efficacy of conventional radiation therapy in the management of malignant gliomas. In this paper a review of different radiotherapeutic modalities including non conventional regiments of irradiation, use of radiosensitizers, boron neutron capture therapy, stereotactic radiosurgery and brachytherapy is presented
Subchronic Hepatotoxicity Evaluation of 2,3,4,6-Tetrachlorophenol in Sprague Dawley Rats
Male Sprague Dawley rats were exposed to 2,3,4,6-tetrachlorophenol (TCP) for 5 days, 2 weeks, 4 weeks, or 13 weeks. TCP was administered by gavage at doses of 0, 10, 25, 50, 100, or 200 mg/kg/day. Endpoints evaluated included clinical observations, body weights, liver weights, serum chemistry, blood TCP, gross pathology, and liver histopathology. There were no TCP exposure-related clinical signs of toxicity. Mean body weight decreased 12–22% compared to control in the 100 and 200 mg/kg/day groups. Serum ALT concentrations were increased in rats of the 200 mg/k/day. Liver weight increases were both dose- and exposure time-related and statistically significant at ≥25 mg/kg/day. Incidence and severity of centrilobular hepatocytic vacuolation, hepatocyte hypertrophy, and single cell hepatocytic necrosis were related to dose and exposure time. Following 13 weeks of exposure, bile duct hyperplasia and centrilobular and/or periportal fibrosis were observed in rats primarily of the highest TCP dose group. Blood TCP concentrations increased with dose and at 13 weeks ranged from 1.3 to 8.5 μg/mL (10 to 200 mg/kg/day). A NOAEL of 10 mg/kg/day was selected based on the statistically significant incidence of hepatocyte hypertrophy at doses ≥25 mg/kg/day
44. Radiation therapy in the treatment of partially resected low-grade cerebellar astrocytomas in adult patients
Between 1975 and 1995, ninety two adult patients received postoperative irradiation for subtotally resected cerebellar tumours, of which 31 were low-grade (I-II) astrocytomas. The median dose of 51 Gy was given. 29 patients showed good tolerance to treatment. The overall 5 and 10-year actuarial survival rates were 78% and 61 % respectively. Age of patients had the strongest influence on prognosis. Young patients (up to 20 years) achieved the 10-year overall actuarial survival rate of 85%, while older patients had poorer survival with the 10-year overall actuarial survival rate of 46% (p=0.0205)
A protocol for manual segmentation of medial temporal lobe subregions in 7 Tesla MRI
Recent advances in MRI and increasing knowledge on the characterization and anatomical variability of medial temporal lobe (MTL) anatomy have paved the way for more specific subdivisions of the MTL in humans. In addition, recent studies suggest that early changes in many neurodegenerative and neuropsychiatric diseases are better detected in smaller subregions of the MTL rather than with whole structure analyses. Here, we developed a new protocol using 7 Tesla (T) MRI incorporating novel anatomical findings for the manual segmentation of entorhinal cortex (ErC), perirhinal cortex (PrC; divided into area 35 and 36), parahippocampal cortex (PhC), and hippocampus; which includes the subfields subiculum (Sub), CA1, CA2, as well as CA3 and dentate gyrus (DG) which are separated by the endfolial pathway covering most of the long axis of the hippocampus. We provide detailed instructions alongside slice-by-slice segmentations to ease learning for the untrained but also more experienced raters. Twenty-two subjects were scanned (19–32 yrs, mean age = 26 years, 12 females) with a turbo spin echo (TSE) T2-weighted MRI sequence with high-resolution oblique coronal slices oriented orthogonal to the long axis of the hippocampus (in-plane resolution 0.44 × 0.44 mm2) and 1.0 mm slice thickness. The scans were manually delineated by two experienced raters, to assess intra- and inter-rater reliability. The Dice Similarity Index (DSI) was above 0.78 for all regions and the Intraclass Correlation Coefficients (ICC) were between 0.76 to 0.99 both for intra- and inter-rater reliability. In conclusion, this study presents a fine-grained and comprehensive segmentation protocol for MTL structures at 7 T MRI that closely follows recent knowledge from anatomical studies. More specific subdivisions (e.g. area 35 and 36 in PrC, and the separation of DG and CA3) may pave the way for more precise delineations thereby enabling the detection of early volumetric changes in dementia and neuropsychiatric diseases
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Innovative Technologies for District Heating and Cooling: InDeal Project
The paper discusses the outcomes of the conference organized by the InDeal project. The conference took place on 12 December 2018 in Montpellier as part of the EnerGaia energy forum 2018. A holistic interdisciplinary approach for district heating and cooling (DHC) networks is presented that integrates heterogeneous innovative technologies from various scientific sectors. The solution is based on a multi-layer control and modelling framework that has been designed to minimize the total plant production costs and optimize heating/cooling distribution. Artificial intelligence tools are employed to model uncertainties associated with weather and energy demand forecasts, as well as quantify the energy storage capacity. Smart metering devices are utilized to collect information about all the crucial heat substations’ parameters, whereas a web-based platform offers a unique user environment for network operators. Three new technologies have been further developed to improve the efficiency of pipe design of DHC systems: (i) A new sustainable insulation material for reducing heat losses, (ii) a new quick-fit joint for an easy installation, and (iii) a new coating for reducing pressure head losses. The results of a study on the development and optimization of two energy harvesting systems are also provided. The assessment of the environmental, economic and social impact of the proposed holistic approach is performed through a life cycle analysis. The validation methodology of the integrated solution is also described, whereas conclusions and future work are finally given
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