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Geriatrie Et Psychologie... Mar 2018In this review of the literature on posterior cortical atrophy (PCA), the history of the disease is first told through the studies of Frank Benson and Oliver Sacks.... (Review)
Review
In this review of the literature on posterior cortical atrophy (PCA), the history of the disease is first told through the studies of Frank Benson and Oliver Sacks. Then, we detail the possible underlying pathologies, Alzheimer's disease being the most common cause. Clinical, cognitive, and biological features are described, with a specific focus on the neuroimaging. We also describe the emotional aspects of PCA. These aspects are often overlooked, but deserve a particular attention due to their impact on the quality of life and prognostic implications for the patients. A multilevel care strategy for PCA patients is suggested.
Topics: Aged; Aged, 80 and over; Alzheimer Disease; Atrophy; Cerebral Cortex; Emotions; Humans; Neuroimaging; Neuropsychological Tests; Vision Disorders
PubMed: 29569567
DOI: 10.1684/pnv.2017.0717 -
Tidsskrift For Den Norske Laegeforening... Jun 2015Posterior cortical atrophy is a neurodegenerative condition with atrophy of posterior parts of the cerebral cortex, including the visual cortex and parts of the parietal... (Review)
Review
BACKGROUND
Posterior cortical atrophy is a neurodegenerative condition with atrophy of posterior parts of the cerebral cortex, including the visual cortex and parts of the parietal and temporal cortices. It presents early, in the 50s or 60s, with nonspecific visual disturbances that are often misinterpreted as ophthalmological, which can delay the diagnosis. The purpose of this article is to present current knowledge about symptoms, diagnostics and treatment of this condition.
METHOD
The review is based on a selection of relevant articles in PubMed and on the authors' own experience with the patient group.
RESULTS
Posterior cortical atrophy causes gradually increasing impairment in reading, distance judgement, and the ability to perceive complex images. Examination of higher visual functions, neuropsychological testing, and neuroimaging contribute to diagnosis. In the early stages, patients do not have problems with memory or insight, but cognitive impairment and dementia can develop. It is unclear whether the condition is a variant of Alzheimer's disease, or whether it is a separate disease entity. There is no established treatment, but practical measures such as the aid of social care workers, telephones with large keypads, computers with voice recognition software and audiobooks can be useful.
INTERPRETATION
Currently available treatment has very limited effect on the disease itself. Nevertheless it is important to identify and diagnose the condition in its early stages in order to be able to offer patients practical assistance in their daily lives.
Topics: Aged; Atrophy; Cerebral Cortex; Disease Progression; Humans; Middle Aged; Neurodegenerative Diseases; Positron-Emission Tomography; Vision Disorders
PubMed: 26037756
DOI: 10.4045/tidsskr.14.1127 -
NeuroImage Nov 2022The thalamus is a central integration structure in the brain, receiving and distributing information among the cerebral cortex, subcortical structures, and the...
The thalamus is a central integration structure in the brain, receiving and distributing information among the cerebral cortex, subcortical structures, and the peripheral nervous system. Prior studies clearly show that the thalamus atrophies in cognitively unimpaired aging. However, the thalamus is comprised of multiple nuclei involved in a wide range of functions, and the age-related atrophy of individual thalamic nuclei remains unknown. Using a recently developed automated method of identifying thalamic nuclei (3T or 7T MRI with white-matter-nulled MPRAGE contrast and THOMAS segmentation) and a cross-sectional design, we evaluated the age-related atrophy rate for 10 thalamic nuclei (AV, CM, VA, VLA, VLP, VPL, pulvinar, LGN, MGN, MD) and an epithalamic nucleus (habenula). We also used T1-weighted images with the FreeSurfer SAMSEG segmentation method to identify and measure age-related atrophy for 11 extra-thalamic structures (cerebral cortex, cerebral white matter, cerebellar cortex, cerebellar white matter, amygdala, hippocampus, caudate, putamen, nucleus accumbens, pallidum, and lateral ventricle). In 198 cognitively unimpaired participants with ages spanning 20-88 years, we found that the whole thalamus atrophied at a rate of 0.45% per year, and that thalamic nuclei had widely varying age-related atrophy rates, ranging from 0.06% to 1.18% per year. A functional grouping analysis revealed that the thalamic nuclei involved in cognitive (AV, MD; 0.53% atrophy per year), visual (LGN, pulvinar; 0.62% atrophy per year), and auditory/vestibular (MGN; 0.64% atrophy per year) functions atrophied at significantly higher rates than those involved in motor (VA, VLA, VLP, and CM; 0.37% atrophy per year) and somatosensory (VPL; 0.32% atrophy per year) functions. A proximity-to-CSF analysis showed that the group of thalamic nuclei situated immediately adjacent to CSF atrophied at a significantly greater atrophy rate (0.59% atrophy per year) than that of the group of nuclei located farther from CSF (0.36% atrophy per year), supporting a growing hypothesis that CSF-mediated factors contribute to neurodegeneration. We did not find any significant hemispheric differences in these rates of change for thalamic nuclei. Only the CM thalamic nucleus showed a sex-specific difference in atrophy rates, atrophying at a greater rate in male versus female participants. Roughly half of the thalamic nuclei showed greater atrophy than all extra-thalamic structures examined (0% to 0.54% per year). These results show the value of white-matter-nulled MPRAGE imaging and THOMAS segmentation for measuring distinct thalamic nuclei and for characterizing the high and heterogeneous atrophy rates of the thalamus and its nuclei across the adult lifespan. Collectively, these methods and results advance our understanding of the role of thalamic substructures in neurocognitive and disease-related changes that occur with aging.
Topics: Adult; Aged; Aged, 80 and over; Aging; Atrophy; Cross-Sectional Studies; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Thalamic Nuclei; Thalamus; Young Adult
PubMed: 36007822
DOI: 10.1016/j.neuroimage.2022.119584 -
The International Journal of... Oct 2013The ubiquitin proteasome system plays a critical role in skeletal muscle atrophy. A large body of research has revealed that many ubiquitin ligases are induced and play... (Review)
Review
The ubiquitin proteasome system plays a critical role in skeletal muscle atrophy. A large body of research has revealed that many ubiquitin ligases are induced and play an important role in mediating the wasting. However, relatively little is known about the roles of deubiquitinases in this process. Although it might be expected that deubiquitinases would be downregulated in atrophying muscles to promote ubiquitination and degradation of muscle proteins, this has not to date been demonstrated. Instead several deubiquitinases are induced in atrophying muscle, in particular USP19 and USP14. USP19, USP2 and A20 are also implicated in myogenesis. USP19 has been most studied to date. Its expression is increased in both systemic and disuse forms of atrophy and can be regulated through a p38 MAP kinase signaling pathway. In cultured muscle cells, it decreases the expression of myofibrillar proteins by apparently suppressing their transcription indicating that the ubiquitin proteasome system may be activated in skeletal muscle to not only increase protein degradation, but also to suppress protein synthesis. Deubiquitinases may be upregulated in atrophy in order to maintain the pool of free ubiquitin required for the increased overall conjugation and degradation of muscle proteins as well as to regulate the stability and function of proteins that are essential in mediating the wasting. Although deubiquitinases are not well studied, these early insights indicate that some of these enzymes play important roles and may be therapeutic targets for the prevention and treatment of muscle atrophy. This article is part of a Directed Issue entitled: Molecular basis of muscle wasting.
Topics: Animals; Humans; Muscle Proteins; Muscle, Skeletal; Muscular Atrophy; Proteasome Endopeptidase Complex; Ubiquitin-Specific Proteases
PubMed: 23680672
DOI: 10.1016/j.biocel.2013.05.002 -
Dermatologie (Heidelberg, Germany) Jan 2023
Topics: Humans; Atrophy; Skin Diseases
PubMed: 35925219
DOI: 10.1007/s00105-022-05040-2 -
Theriogenology Aug 2022In recent years, Duck Tembusu virus (DTMUV) is becoming an important emerging and re-emerging pathogen that severely harms the poultry industry in China. The DTMUV...
In recent years, Duck Tembusu virus (DTMUV) is becoming an important emerging and re-emerging pathogen that severely harms the poultry industry in China. The DTMUV disease was principally identified by a sharp decline in egg production, whereas few studies were focused on the virus-reproductive system interaction, especially male reproductive system. Herein, the present study was aimed at investigating the in vivo morphological changes in testis from DTMUV-infected adult Shaoxing ducks. After DTMUV infection, the gross observation indicated that the testis of DTMUV-infected ducks was significantly atrophied at 2 days post-infection (dpi), 4 dpi, and 8 dpi. At microscopic and ultrastructural level, morphological analysis revealed that DTMUV could lead to cytoplasmic vacuolation and exfoliation in seminiferous epithelium, decrease in the diameter of seminiferous tubule (ST), and even induce interstitial inflammation in duck testis. Ulteriorly, the spermatogenic cells, especially spermatocytes, are identified as the target cells of DTMUV infection in the testis of ducks through immunohistochemistry (IHC). And more notably, single virus particles and clustered virus particles were observed in the spermatogenic cells from infected ducks. In summary, our results comprehensively illustrated the effects of DTMUV infection on the testis, the morphological changes underlying testicular atrophy and identified the target cells of DTMUV infection in the testis of ducks.
Topics: Animals; Atrophy; Ducks; Flavivirus; Flavivirus Infections; Male; Poultry Diseases; Testis
PubMed: 35661989
DOI: 10.1016/j.theriogenology.2022.05.012 -
Archives of Neurology Aug 1961
Topics: Child; Humans; Infant; Muscular Atrophy; Spinal Muscular Atrophies of Childhood
PubMed: 13689565
DOI: 10.1001/archneur.1961.00450140022003 -
Neurology Mar 1956
Topics: Atrophy; Cerebellopontine Angle; Disease; Olivopontocerebellar Atrophies
PubMed: 13297122
DOI: 10.1212/wnl.6.3.218 -
International Journal of Sports Medicine Oct 1997Skeletal muscle adapts to loading; atrophying when exposed to unloading on Earth or in spaceflight. Significant atrophy (decreases in muscle fiber cross-section of... (Review)
Review
Skeletal muscle adapts to loading; atrophying when exposed to unloading on Earth or in spaceflight. Significant atrophy (decreases in muscle fiber cross-section of 11-24%) in humans has been noted after only 5 days in space. Since muscle strength is determined both by muscle cross-section and synchronization of motor unit recruitment, a loss in muscle size weakens astronauts, which would increase risks to their safety if an emergency required maximal muscle force. Numerous countermeasures have been tested to prevent atrophy. Resistant exercise together with growth hormone and IGF-I are effective countermeasures to unloading as most atrophy is prevented in animal models. The loss of muscle protein is due to an early decrease in protein synthesis rate and a later increase in protein degradation. The initial decrease in protein synthesis is a result of decreased protein translation, caused by a prolongation in the elongation rate. A decrease in HSP70 by a sight increase in ATP may be the factors prolonging elongation rate. Increases in the activities of proteolytic enzymes and in ubiquitin contribute to the increased protein degradation rate in unloaded muscle. Numerous mRNA concentrations have been shown to be altered in unloaded muscles. Decreases in mRNAs for contractile proteins usually occur after the initial fall in protein synthesis rates. Much additional research is needed to determine the mechanism by which muscle senses the absence of gravity with an adaptive atrophy. The development of effective countermeasures to unloading atrophy will require more research.
Topics: Adaptation, Physiological; Animals; Exercise; Humans; Muscle Proteins; Muscle, Skeletal; Muscular Atrophy; RNA, Messenger; Weightlessness; Weightlessness Countermeasures
PubMed: 9391829
DOI: 10.1055/s-2007-972723 -
The Medical Journal of Malaysia Jan 2023Studies are lacking in evaluating brain atrophy patterns in the Malaysian population. This study aimed to compare the patterns of cerebral atrophy and impaired glucose...
INTRODUCTION
Studies are lacking in evaluating brain atrophy patterns in the Malaysian population. This study aimed to compare the patterns of cerebral atrophy and impaired glucose metabolism on F-FDG PET/CT imaging in various stages of AD in a Klang Valley population by using voxelbased morphometry in SPM12.
MATERIALS AND METHODS
F-FDG PET/CT images of 14 healthy control (HC) subjects (MoCA score > 26 (mean+SD~ 26.93+0.92) with no clinical evidence of cognitive deficits or neurological disease) and 16 AD patients (MoCA ≤22 (mean+SD~18.6+9.28)) were pre-processed in SPM12 while using our developed Malaysian healthy control brain template. The AD patients were assessed for disease severity using ADAS-Cog neuropsychological test. KNE96 template was used for registration-induced deformation in comparison with the ICBM templates. All deformation fields were corrected using the Malaysian healthy control template. The images were then nonlinearly modified by DARTEL to segment grey matter (GM), white matter (WM) and cerebrospinal fluid (CSF) to produce group-specific templates. Age, intracranial volume, MoCA score, and ADASCog score were used as variables in two sample t test between groups. The inference of our brain analysis was based on a corrected threshold of p<0.001 using Z-score threshold of 2.0, with a positive value above it as hypometabolic. The relationship between regional atrophy in GM and WM atrophy were analysed by comparing the means of cortical thinning between normal control and three AD stages in 15 clusters of ROI based on Z-score less than 2.0 as atrophied.
RESULTS
One-way ANOVA indicated that the means were equal for TIV, F(2,11) = 1.310, p=0.309, GMV, F(2,11) = 0.923, p=0.426, WMV, F(2,11) = 0.158, p=0.856 and CSF, F(2,11) = 1.495 p=0.266. Pearson correlations of GM, WM and CSF volume between HC and AD groups indicated the presence of brain atrophy in GM (p=-0.610, p<0.0001), WM (p=-0.178, p=0.034) and TIV (p=-0.374, p=0.042) but showed increased CSF volume (p=0.602, p<0.0001). Voxels analysis of the 18FFDG PET template revealed that GM atrophy differs significantly between healthy control and AD (p<0.0001). Zscore comparisons in the region of GM & WM were shown to distinguish AD patients from healthy controls at the prefrontal cortex and parahippocampal gyrus. The atrophy rate within each ROI is significantly different between groups (c=35.9021, df=3, p<0.0001), Wilcoxon method test showed statistically significant differences were observed between Moderate vs. Mild AD (p<0.0001), Moderate AD vs. healthy control (p=0.0005), Mild AD vs. HC (p=0.0372) and Severe AD vs. Moderate AD (p<0.0001). The highest atrophy rate within each ROI between the median values ranked as follows severe AD vs. HC (p<0.0001) > mild AD vs. HC (p=0.0091) > severe AD vs. moderate AD (p=0.0143).
CONCLUSION
We recommend a reliable method in measuring the brain atrophy and locating the patterns of hypometabolism using a group-specific template registered to a quantitatively validated KNE96 group-specific template. The studied regions together with neuropsychological test approach is an effective method for the determination of AD severity in a Malaysian population.
Topics: Humans; Alzheimer Disease; Positron Emission Tomography Computed Tomography; Fluorodeoxyglucose F18; Magnetic Resonance Imaging; Brain; Atrophy
PubMed: 36715191
DOI: No ID Found