Neurodegeneration involving putative respiratory neurons in Perry syndrome
ABSTRACT The objective of this study was to assess the potential involvement of ventral medullary neurons implicated in respiratory rhythmogenesis and chemosensitivity in a patient with Perry syndrome (autosomal dominant parkinsonism associated with depression, weight loss and central hypoventilation). Previous neuropathologic reports in Perry syndrome demonstrated neuronal loss in the substantia nigra with no or few Lewy bodies and no tau inclusions. Neurons in the pre-Bötzinger complex (preBötC) of the ventrolateral medulla, identified by their immunoreactivity for neurokinin-1 receptors (NK-1R), play an essential role in respiratory rhythmogenesis and serotonergic neurons in the medullary raphe in respiratory chemosensitivity, but their potential involvement in Perry syndrome has not yet been addressed. We conducted clinical and neuropathologic studies including immunohistochemistry examination in a new autopsied case clinically diagnosed as Perry syndrome. Our patient presented with parkinsonism at age 41. Subsequently, all cardinal features of Perry syndrome developed. He died of respiratory failure and sepsis at age 46. Hematoxylin-eosin staining revealed no significant pathology in the medulla. However, NK-1R, tyrosine hydroxylase (TH) and tryptophan hydroxylase (TrOH) immunoreactive neurons were significantly reduced in the ventrolateral medulla compared to controls. There was also loss of serotonergic neurons in the medullary raphe and ventral medullary surface. Severe neuronal loss in the substantia nigra, without alpha-synuclein or tau pathology but with loss of NK-1R and TH immunoreactive neurons in the ventrolateral medulla, and loss of serotonergic neurons in the medullary raphe and ventrolateral medulla may be a pathologic hallmark of Perry syndrome.
Conference Paper: Role ordering scheduler for concurrency control in distributed objects[Show abstract] [Hide abstract]
ABSTRACT: Concepts of roles are significant to design and implement access control models in secure information systems. A role shows a job Junction in an enterprise. In addition to keeping systems secure, objects have to be consistent in presence of multiple transactions. Traditional locking protocols and timestamp ordering schedulers are based on principles "first-comer-winner" and "timestamp order" to make multiple transactions serializable, respectively. Each transaction is associated with a role. We define significancy of role where shows how significant each role is in an enterprise. We discuss a novel type of scheduler for concurrency control so that multiple conflicting transactions are serializable in a significant order of roles of transactions.Parallel and Distributed Systems, 2004. ICPADS 2004. Proceedings. Tenth International Conference on; 08/2004
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ABSTRACT: Autosomal dominant parkinsonism, hypoventilation, depression and weight loss (Perry syndrome) has been reported in only seven families worldwide. It is a rapidly progressive disease leading to death from respiratory insufficiency within a few years. Parkinsonism is usually mild, with bradykinesia, rigidity, rest and postural tremor, and axial signs. Response to levodopa is poor although transient response has been occasionally observed. The early signs include parkinsonism, depression and weight loss, whereas hypoventilation is a late feature. Neuropathology shows severe neuronal loss in the substantia nigra, less prominent neuronal loss in the locus coeruleus, and no or few Lewy bodies. In this review, we also propose diagnostic criteria for this condition.Parkinsonism & Related Disorders 02/2008; 14(1):1-7. DOI:10.1016/j.parkreldis.2007.07.014 · 4.13 Impact Factor
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ABSTRACT: The neuropathology of human sleep remains an ill-defined issue. The data concerning the main structures of human brain areas involved, or supposed to be implicated, in sleep organisation are reviewed. Five levels of organisation can be schematically recognized: (i) the ascending arousal system, (ii) the non REM and REM systems (iii) regulated by hypothalamic areas, (iv) and the biological clock, (v) modulated by a number of “allostatic” influences. These are briefly described, with emphasis on the location of structures involved in humans, and on the recently revised concepts. Current knowledge on the topography of lesions associated with the main sleep disorders in degenerative diseases is recalled, including REM sleep behavior disorders, restless legs syndrome and periodic leg movements, sleep apneas, insomnia, excessive daily sleepiness, secondary narcolepsy and disturbed sleep–wake rhythms. The lesions of sleep related structures observed in early and late stages of four degenerative diseases are then reviewed. Two synucleinopathies (Lewy lesions associated disorders, including Parkinson's disease and Dementia with Lewy bodies, and Multiple System Atrophy) and two tauopathies (Progressive Supranuclear Palsy and Alzheimer's disease) are dealt with. The distribution of lesions usually found in affected patients fit with that expected from the prevalence of different sleep disorders in these diseases. This confirms the current opinion that these disorders depend on the distribution of lesions rather than on their biochemical nature. Further studies might throw insight on the mechanism of normal and pathological sleep in humans, counterpart of the increasing knowledge provided by animal models. Specially designed prospective clinicopathological studies including peculiar attention to sleep are urgently needed.Revue Neurologique 08/2008; 164(8):669-682. DOI:10.1016/j.neurol.2008.07.003 · 0.60 Impact Factor