Matter Loss (matter + loss)

Distribution by Scientific Domains


Selected Abstracts


A novel ARX phenotype: rapid neurodegeneration with Ohtahara syndrome and a dyskinetic movement disorder

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 3 2010
MICHAEL ABSOUD
ARX mutations are associated with variable clinical phenotypes. We report a new neurodegenerative phenotype associated with a known ARX mutation and causing early abnormal neurodevelopment, a complex movement disorder, and early infantile epileptic encephalopathy with a suppression-burst pattern (Ohtahara syndrome). A male infant presented at age 5 months with a dyskinetic movement disorder, which was initially diagnosed as infantile spasms. Clinical deterioration was accompanied by progressive cortical atrophy with a reduction in white matter volume and resulting in death in the first year of life; such a rapidly progressive and severe phenotype has not previously been described. ARX mutation testing should be undertaken in children aged less than 1 year with Ohtahara syndrome and a movement disorder, and in infants with unexplained neurodegeneration, progressive white matter loss, and cortical atrophy. [source]


A comparison between the accuracy of voxel-based morphometry and hippocampal volumetry in Alzheimer's disease

JOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 3 2004
Cristina Testa PhD
Abstract Purpose To compare the accuracy of voxel-based morphometry (VBM) and region of interest (ROI)-based hippocampal volumetry to detect medial temporal lobe atrophy in Alzheimer's disease (AD). Materials and Methods A total of 27 AD patients (age 74 ± 9 years; 22 women; Mini-Mental State Exam [MMSE] 21 ± 4) and 25 controls (age 70 ± 8; 16 women; MMSE 29 ± 1) were studied. Accuracy of VBM to detect gray matter loss in those seven AD patients and 11 controls with similar ROI-based hippocampal measures and of ROI-based volumetry to detect gray matter loss in those four AD patients and five controls with similar VBM-based hippocampal measures was assessed. VBM was performed with statistical parametric mapping (SPM99). Results The area under the curve was 0.96 (95% C.I., 0.92,1.00) for VBM, 0.89 (95% C.I., 0.80,0.98) for ROI-based hippocampal measures, and 0.99 (95% C.I., 0.96,1.00) for both. In subjects with similar ROI-based hippocampal measures, VBM detected atrophy in AD patients at P < 0.0001, while in subjects with similar VBM-based hippocampal measure, volumetry was not significant (P = 0.11). Both measures independently contributed to discrimination (P = 0.004 and P = 0.032) in a logistic regression model. Conclusion These results indicate that VBM is more accurate, but the combination of both methods provides the highest accuracy for detection of hippocampal atrophy in AD. J. Magn. Reson. Imaging 2004;19:274,282. © 2004 Wiley-Liss, Inc. [source]


The role of neuroimaging in mild cognitive impairment

NEUROPATHOLOGY, Issue 6 2007
Hiroshi Matsuda
The main purposes of neuroimaging in Alzheimer's disease (AD) have been moved from diagnosis of advanced AD to diagnosis of very early AD at a prodromal stage of mild cognitive impairment, prediction of conversion from mild cognitive impairment (MCI) to AD, and differential diagnosis from other diseases causing dementia. Structural MRI studies and functional studies using F-18 fluorodeoxyglucose-positron emission tomography (FDG-PET) and brain perfusion single-photon emission computed tomography (SPECT) are widely used in diagnosis of AD. Outstanding progress in diagnostic accuracy of these neuroimaging modalities has been obtained using statistical analysis on a voxel-by-voxel basis after spatial normalization of individual scans to a standardized brain-volume template instead of visual inspection or a conventional region of interest technique. In a very early stage of AD, this statistical approach revealed gray matter loss in the entorhinal and hippocampal areas and hypometabolism or hypoperfusion in the posterior cingulate cortex and precuneus. These two findings might be related in view of anatomical knowledge that the regions are linked through the circuit of Papez. This statistical approach also offers prediction of conversion from MCI to AD. Presence of hypometabolism or hypoperfusion in parietal association areas and entorhinal atrophy at the MCI stage has been reported to predict rapid conversion to AD. [source]


Substitution of fishmeal with soybean meal in practical diets for juvenile white shrimp Litopenaeus schmitti (Pérez-Farfante & Kensley 1997)

AQUACULTURE RESEARCH, Issue 7 2007
Josefa Susana Alvarez
Abstract The feasibility of substituting soybean meal for fishmeal diets for juvenile white shrimp Litopenaeus schmitti (0.35±0.01 g) was evaluated, and an adequate substitution level was determined. Five diets were evaluated using 46%, 59%, 75%, 88% and 100% substitution levels. Pellet water stability was significantly affected by dietary soybean content (P<0.05). Increased soybean content produced lower pellet stability, ranging from a dry matter loss of 14,22% after a 2-h immersion, and 20,33% after an 8-h immersion. After 52 days, significant differences (P<0.05) were found in shrimp weight, feed conversion ratio and protein efficiency ratio. The values were 0.64,1.06 g, 2.8,7.9 and 0.45,1.21, respectively, for the three measurements. Overall, better results were obtained with diets where soybean meal was substituted for fishmeal up to 75%. The 100% soybean meal diet resulted in poor growth performance of shrimp. Survival rates were acceptable for all treatments (90% or higher) and no significant differences were found in survival between treatments. Regression analysis using the broken-line methodology indicated that 76.5±2% is an optimum soybean substitution level in diets that contained fishmeal and soybean as the major protein sources for grow-out of juvenile white shrimp. [source]


Cerebral MRI findings in a cohort of ex-preterm and control adolescents

ACTA PAEDIATRICA, Issue 6 2009
Zoltan Nagy
Abstract Aim: Newborn infants were entered between 1988 and 1993 into a prospective, long-term, follow-up study. We aimed to investigate how the outcome of preterm-born individuals on cerebral magnetic resonance imaging (MRI) compared to that reported on similar cohorts internationally. Methods: The 74 ex-preterm (12.38,17.7 years, 51% girls) and 69 control participants (12.18,16.47 years, 53% girls) underwent a MRI examination on a 1.5T scanner. Two experienced neuroradiologists examined the T1- and T2-weigthed images first independently and then in consensus without knowledge of group adherence. Results: Only 21 (4 controls) of the 143 sets of scans showed any abnormalities. All but one of these were of mild extent. Among the ex-preterm adolescents two showed only incidental findings while the other 15 had either gliosis or white matter loss. Eleven subjects had white matter loss, seven of which had no other abnormalities. Four subjects had gliosis, three of which had no other abnormalities. The extent, severity or frequency of injury was not related to being born small for gestational age. Conclusion: Although the rate of structural abnormalities was higher in the group of adolescents born preterm, this rate was well below that reported from other centres around the world. We attribute this to the minimally invasive neonatal care and to different social structures in Sweden compared to that of other reports on similar cohorts. [source]