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91.
FDG‐PET IN HEALTHY AND EPILEPTIC LAGOTTO ROMAGNOLO DOGS AND CHANGES IN BRAIN GLUCOSE UPTAKE WITH AGE
Tarja S. Jokinen Merja Haaparanta‐Solin Ranno Viitmaa Tove J. Grönroos Jarkko Johansson Luciana Bergamasco Marjatta Snellman Liisa Metsähonkala 《Veterinary radiology & ultrasound》2014,55(3):331-341
Regional cerebral metabolism and blood flow can be measured noninvasively with positron emission tomography (PET). 2‐[18F]fluoro‐2‐deoxy‐D‐glucose (FDG) widely serves as a PET tracer in human patients with epilepsy to identify the seizure focus. The goal of this prospective study was to determine whether juvenile or adult dogs with focal‐onset epilepsy exhibit abnormal cerebral glucose uptake interictally and whether glucose uptake changes with age. We used FDG‐PET to examine six Lagotto Romagnolo dogs with juvenile epilepsy, two dogs with adult‐onset epilepsy, and five control dogs of the same breed at different ages. Three researchers unaware of dog clinical status visually analyzed co‐registered PET and magnetic resonance imaging (MRI) images. Results of the visual PET analyses were compared with electroencephalography (EEG) results. In semiquantitative analysis, relative standard uptake values (SUV) of regions of interest (ROI) drawn to different brain regions were compared between epileptic and control dogs. Visual analysis revealed areas of hypometabolism interictally in five out of six dogs with juvenile epilepsy in the occipital, temporal, and parietal cortex. Changes in EEG occurred in three of these dogs in the same areas where PET showed cortical hypometabolism. Visual analysis showed no abnormalities in cerebral glucose uptake in dogs with adult‐onset epilepsy. Semiquantitative analysis detected no differences between epileptic and control dogs. This result emphasizes the importance of visual analysis in FDG‐PET studies of epileptic dogs. A change in glucose uptake was also detected with age. Glucose uptake values increased between dog ages of 8 and 28 weeks and then remained constant. 相似文献
92.
Ranno Viitmaa Merja Haaparanta‐Solin Marjatta Snellman Sigitas Cizinauskas Toomas Orro Erja Kuusela Jarkko Johansson Tapio Viljanen Tarja S. Jokinen Luciana Bergamasco Liisa Metsähonkala 《Veterinary radiology & ultrasound》2014,55(4):453-461
In human epileptic patients, changes in cerebral glucose utilization can be detected 2‐deoxy‐2‐[18F] fluoro‐d ‐glucose positron emission tomography (FDG‐PET). The purpose of this prospective study was to determine whether epileptic dogs might show similar findings. Eleven Finnish Spitz dogs with focal idiopathic epilepsy and six healthy dogs were included. Dogs were examined using electroencephalography (EEG) and FDG‐PET, with epileptic dogs being evaluated during the interictal period. Visual and semi‐quantitative assessment methods of FDG‐PET were compared and contrasted with EEG findings. Three independent observers, unaware of dog clinical status, detected FDG‐PET uptake abnormalities in 9/11 epileptic (82%), and 4/8 healthy dogs (50%). Occipital cortex findings were significantly associated with epileptic status (P = 0.013). Epileptic dogs had significantly lower standardized uptake values (SUVs) in numerous cortical regions, the cerebellum, and the hippocampus compared to the control dogs. The lowest SUVs were found in the occipital lobe. White matter normalized and left‐right asymmetry index values for all pairs of homologous regions did not differ between groups. Visual evaluation of the EEGs was less sensitive (36%) than FDG‐PET. Both diagnostic tests were consensual and specific (100%) for occipital findings, but EEG had a lower sensitivity for detecting lateralized foci than FDG‐PET. Findings supported the use of FDG‐PET as a diagnostic test for dogs with suspected idiopathic epilepsy. Visual and semiquantitative analyses of FDG‐PET scans provided complementary information. Findings also supported the theory that epileptogenesis may occur in multiple brain regions in Finnish Spitz dogs with idiopathic epilepsy. 相似文献
93.
Askebjer P Barwick SW Bergström L Bouchta A Carius S Coulthard A Engel K Erlandsson B Goobar A Gray L Hallgren A Halzen F Hulth PO Jacobsen J Johansson S Kandhadai V Liubarsky I Lowder D Miller T Mock PC Morse R Porrata R Price PB Richards A Rubinstein H Schneider E Sun Q Tilav S Walck C Yodh G 《Science (New York, N.Y.)》1995,267(5201):1147-1150
The optical properties of the ice at the geographical South Pole have been investigated at depths between 0.8 and 1 kilometer. The absorption and scattering lengths of visible light ( approximately 515 nanometers) have been measured in situ with the use of the laser calibration setup of the Antarctic Muon and Neutrino Detector Array (AMANDA) neutrino detector. The ice is intrinsically extremely transparent. The measured absorption length is 59 +/- 3 meters, comparable with the quality of the ultrapure water used in the Irvine-Michigan-Brookhaven and Kamiokande proton-decay and neutrino experiments and more than twice as long as the best value reported for laboratory ice. Because of a residual density of air bubbles at these depths, the trajectories of photons in the medium are randomized. If the bubbles are assumed to be smooth and spherical, the average distance between collisions at a depth of 1 kilometer is about 25 centimeters. The measured inverse scattering length on bubbles decreases linearly with increasing depth in the volume of ice investigated. 相似文献
94.
Technology now being introduced in industry, buildings, and transportation is much more energy-efficient than today's average technology. Changes in production and consumption are tending to decrease the intensity of energy use. By applying available economic technology, it may be possible to reduce energy use in Sweden from the present 1400 petajoules per year to about 900 petajoules per year soon after the turn of the century, even with a 50 percent increase in the consumption of goods and services. Technology now being developed could reduce energy demand even further. 相似文献
95.
Lükewille Anke Bertok Imrich Amann Markus Cofala Janusz Gyarfas Frantisek Johansson Matti Klimont Zbigniew Pacyna Elisabeth Pacyna Jozef 《Water, air, and soil pollution》2001,130(1-4):229-234
Primary particulate matter is emitted directly into the atmosphere from various anthropogenic and natural sources such as power plants (combustion of fossil fuels) or forest fires. Secondary particles are formed by transformation of SO2, NOx, NH3, and VOC in the atmosphere. They both contribute to ambient particulate matter concentrations, which may have adverse effects on human health. Health hazards are caused by small particulate size, high number of especially fine (< 2.5 µm) and ultra-fine (< 0.1 µm) particles and/or their chemical composition. As part of an integrated assessment model developed at IIASA, a module on primary particulate matter (PM) emissions has been added to the existing SO2, NOx, NH3 and VOC sections. The module considers so far primary emissions of total suspended particles (TSP), PM10 and PM2.5 from aggregated stationary and mobile sources. A primary PM emission database has been established. Country specific emission factors for stationary sources have been calculated within the module using the ash content of solid fuels. 相似文献
96.
OBJECTIVE: To determine changes in reported food frequency in adults between 1986 and 1999. DESIGN: Four consecutive cross-sectional surveys. SETTING: Counties of Norrbotten and V?sterbotten, Northern Sweden. SUBJECTS: The Northern Sweden MONICA (Monitoring of Trends and Determinants in Cardiovascular Disease) population, four independent cross-sectional surveys in 1986, 1990, 1994 and 1999. Randomly selected age-stratified samples of the population aged 25-64 years. Analysis is based on 2982 males and 3087 females who completed an 84-item food-frequency questionnaire. RESULTS: Between 1986 and 1999, average reported consumption of 3%-fat milk decreased from 42 to 7 intakes month(-1) in men and from 28 to 4 intakes month(-1) in women. Reported use of 1.5%-fat milk increased from 6 to 27 intakes month(-1) in men and from 6 to 24 in women. Monthly intakes of potatoes and root vegetables decreased from 38 to 27 in men and from 39 to 32 in women. Consumption of pasta increased from 4 to 7 intakes month(-1) in both sexes. Intakes of solid fats with 80% fat content dropped from 92 to 62 per month in men and from 78 to 52 per month in women, whereas use of 40%-fat spread increased from 12 to 22 intakes month(-1) in men and from 5 to 26 in women. Monthly intakes of vegetable oil increased from 3 to 12 in men and from 3 to 15 in women. The percentage of overweight or obese individuals (body mass index >25 kg m(-2)) increased from 52 to 65% in men and from 41 to 52% in women (P for linear trend in all these changes, <0.001). CONCLUSIONS: Our data indicate reduced consumption of foods with a high content of saturated fats. In spite of that, there is an unbroken trend towards increased obesity. 相似文献
97.
98.
OBJECTIVES: To examine dietary iodine sources and to estimate the dietary iodine intake of the Norwegian population. DESIGN: Food iodine analyses carried out in Norway during the last 10 years were compiled, and iodine intake calculated on the basis of food intake data from nation-wide dietary surveys among children and adults. The food intake of adults was measured by a self-administrated food-frequency questionnaire, which covered habitual diet during the past year. The food intake of children was measured by dietary record during four consecutive days. SETTING: Neither household nor industrial iodisation of salt is mandatory in Norway, but some brands of table salt have 5 microg of iodine added per gram of NaCl. In spite of this, the population has been considered iodine-replete for decades, i.e. having an iodine intake well above the Recommended Dietary Allowance of 150 microg day(-1). This assumption has not been substantiated by dietary surveys. SUBJECTS: The adults included 1374 females and 1298 males aged 16-79 years. The children included 185 girls and 206 boys aged 4 years, 411 girls and 404 boys aged 9 years, and 517 girls and 492 boys aged 13 years. RESULTS: The calculated iodine intake was in the range of 100-250 microg day(-1) in the majority of the adult population. The mean iodine intake was 136 microg day(-1) (170 microg I/10 MJ) among women and 176 microg day(-1) (161 microg I/10 MJ) among men. For children the iodine intake was in the range of 100-120 microg day(-1). Milk and dairy products contributed approximately 55% and 70% of the dietary iodine intake in adults and children, respectively. Fish contributed more than 20% of the iodine intake in adults and about 10% in children. The iodine contribution of drinking water was negligible. CONCLUSIONS: While fish has the highest natural concentration of iodine and as such is an excellent iodine source, milk and diary products are the main determinants of iodine intake in the Norwegian population. Iodisation of cow fodder has been mandatory in Norway since 1950 and provides an efficient alternative to universal salt iodisation. Our results show that the dietary iodine intake of adults is in the range considered to be sufficient. The dietary intake of iodine was at recommended levels among the youngest children; however, it decreased among adolescents, especially among girls. 相似文献
99.
100.