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Dementia Complex (dementia + complex)
Kinds of Dementia Complex Selected AbstractsAIDS dementia complex and Hashimoto encephalopathy in a senescent womanINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 12 2007Robert Waltereit Abstract AIDS dementia complex is one of the specific infectious dementias, which is rarely seen in senescent (>75 years of age) subjects. Hashimoto encephalopathy has been described as the cause of several neurological and psychiatric syndromes including dementia. The proposed pathophysiological mechanism is an autoimmune reaction to shared, thyroid gland and CNS epitopes with subsequent cerebral dysfunction. We report here the first case of a patient who fulfils both, the criteria for AIDS dementia complex and Hashimoto encephalopathy, yet being unresponsive to steroid therapy. Diagnostic and therapeutic implications are discussed. Copyright © 2007 John Wiley & Sons, Ltd. [source] A multi-center 1H MRS study of the AIDS dementia complex: Validation and preliminary analysisJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 6 2003Patricia Lani Lee PhD Abstract Purpose To demonstrate the technical feasibility and reliability of a multi-center study characterizing regional levels of the brain metabolite ratios choline (Cho)/creatine (Cr) and myoinositol (MI)/Cr, markers of glial cell activity, and N-acetyl aspartate (NAA)/Cr, a marker of mature neurons, in subjects with AIDS dementia complex (ADC). Materials and Methods Using an automated protocol (GE PROBE-P), short echo time spectra (TE = 35 msec) were obtained at eight sites from uniformly prepared phantoms and from three brain regions (frontal white matter, basal ganglia, and parietal cortex) of normal volunteers and ADC and HIV-negative subjects. Results A random-effects model of the phantom and volunteer data showed no significant inter-site differences. Feasibility of a multi-center study was further validated by detection of significant differences between the metabolite ratios of ADC subjects and HIV-negative controls. ADC subjects exhibited significantly higher Cho/Cr and MI/Cr in the basal ganglia and significantly reduced NAA/Cr and significantly higher MI/Cr in the frontal white matter. These results are consistent with the predominantly subcortical distribution of the pathologic abnormalities associated with ADC. Conclusion This is the first study to ascertain and validate the reliability and reproducibility of a short echo time 1H-MRS acquisition sequence from multiple brain regions in a multi-center setting. It should now be possible to examine the regional effects of HIV infection in the brain in a large number of subjects and to study the metabolic effects of new therapies for the treatment of ADC in a clinical trial setting. J. Magn. Reson. Imaging 2003;17:625,633. © 2003 Wiley-Liss, Inc. [source] Parkinsonism,dementia complex of GuamMOVEMENT DISORDERS, Issue S12 2005John C. Steele MD Abstract On Guam and in two other Pacific locales, indigenous residents and immigrants are prone to familial neurodegeneration that manifests as atypical parkinsonism, dementia, motor neuron disease, or a combination of these three phenotypes. This progressive and fatal disease of the Mariana islands, the Kii peninsula of Japan, and the coastal plain of West New Guinea is similar and the pathological features have close affiliation with universal tauopathies, including progressive supranuclear palsy, Alzheimer's disease, and amyotrophic lateral sclerosis. The Chamorros of Guam call the disease lytico-bodig, and neuroscientists refer to it as the amyotrophic lateral sclerosis/Parkinsonism,dementia complex. During recent decades, its prevalence has declined progressively, and the age at onset has steadily increased. In 2004, motor neuron disease, once 100 times more common than elsewhere is rare, atypical parkinsonism is declining, and only dementia remains unusually common in elderly females. The cause of this obscure malady remains uncertain, despite 60 years of international research, but its ending implicates environmental influences rather than genetic predisposition. © 2005 Movement Disorder Society [source] Commentary on: return of the cycad hypothesis , does the amyotrophic lateral sclerosis/Parkinsonism dementia complex (ALS/PDC) of Guam have new implications for global health?NEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 6 2006P. A. Cox First page of article [source] Return of the cycad hypothesis , does the amyotrophic lateral sclerosis/parkinsonism dementia complex (ALS/PDC) of Guam have new implications for global health?NEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 4 2005P. G. Ince Recently published work provides evidence in support of the cycad hypothesis for Lytico,Bodig, the Guamanian amyotrophic lateral sclerosis/parkinsonism dementia complex (ALS/PDC), based on a new understanding of Chamorro food practices, a cyanobacterial origin of ,-methylaminoalanine (BMAA) in cycad tissue, and a possible mechanism of biomagnification of this neurotoxic amino acid in the food chain. BMAA is one of two cycad chemicals with known neurotoxic properties (the other is cycasin, a proven developmental neurotoxin) among the many substances that exist in these highly poisonous plants, the seeds of which are used by Chamorros for food and medicine. The traditional diet includes the fruit bat, a species that feeds on cycad seed components and reportedly bioaccumulates BMAA. Plant and animal proteins provide a previously unrecognized reservoir for the slow release of this toxin. BMAA is reported in the brain tissue of Guam patients and early data suggest that some Northern American patients dying of Alzheimer's disease (AD) have detectable brain levels of BMAA. The possible role of cyanobacterial toxicity in sporadic neurodegenerative disease is therefore worthy of consideration. Recent neuropathology studies of ALS/PDC confirm understanding of this disorder as a ,tangle' disease, based on variable anatomical burden, and showing biochemical characteristics of ,AD-like' combined 3R and 4R tau species. This model mirrors the emerging view that other neurodegenerative disease spectra comprise clusters of related syndromes, owing to common molecular pathology, with variable anatomical distribution in the nervous system giving rise to different clinical phenotypes. Evidence for ,ubiquitin-only' inclusions in ALS/PDC is weak. Similarly, although there is evidence for ,-synucleinopathy in ALS/PDC, the parkinsonian component of the disease is not caused by Lewy body disease. The spectrum of sporadic AD includes involvement of the substantia nigra and a high prevalence of ,incidental',-synucleinopathy in sporadic AD is reported. Therefore the pathogenesis of Lytico,Bodig appears still to have most pertinence to the ongoing investigation of the pathogenesis of AD and other tauopathies. [source] Environmental neurotoxin-induced progressive model of parkinsonism in ratsANNALS OF NEUROLOGY, Issue 1 2010Wei-Bin Shen PhD Objective Exposure to a number of drugs, chemicals, or environmental factors can cause parkinsonism. Epidemiologic evidence supports a causal link between the consumption of flour made from the washed seeds of the plant Cycas micronesica by the Chamorro population of Guam and the development of amyotrophic lateral sclerosis/parkinsonism dementia complex. Methods We now report that consumption of washed cycad flour pellets by Sprague-Dawley male rats induces progressive parkinsonism. Results Cycad-fed rats displayed motor abnormalities after 2 to 3 months of feeding such as spontaneous unilateral rotation, shuffling gait, and stereotypy. Histological and biochemical examination of brains from cycad-fed rats revealed an initial decrease in the levels of dopamine and its metabolites in the striatum (STR), followed by neurodegeneration of dopaminergic (DAergic) cell bodies in the substantia nigra (SN) pars compacta (SNc). ,-Synuclein (,-syn; proteinase K-resistant) and ubiquitin aggregates were found in the DAergic neurons of the SNc and neurites in the STR. In addition, we identified ,-syn aggregates in neurons of the locus coeruleus and cingulate cortex. No loss of motor neurons in the spinal cord was found after chronic consumption of cycad flour. In an organotypic slice culture of the rat SN and the striatum, an organic extract of cycad causes a selective loss of dopamine neurons and ,-syn aggregates in the SN. Interpretation Cycad-fed rats exhibit progressive behavioral, biochemical, and histological hallmarks of parkinsonism, coupled with a lack of fatality. ANN NEUROL 2010;68:70,80 [source] Cyanobacterial neurotoxin BMAA in ALS and Alzheimer's diseaseACTA NEUROLOGICA SCANDINAVICA, Issue 4 2009J. Pablo Objective,,, The aim of this study was to screen for and quantify the neurotoxic amino acid ,- N -methylamino- l -alanine (BMAA) in a cohort of autopsy specimens taken from Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), Huntington's disease (HD), and non-neurological controls. BMAA is produced by cyanobacteria found in a variety of freshwater, marine, and terrestrial habitats. The possibility of geographically broad human exposure to BMAA had been suggested by the discovery of BMAA in brain tissues of Chamorro patients with ALS/Parkinsonism dementia complex from Guam and more recently in AD patients from North America. These observations warranted an independent study of possible BMAA exposures outside of the Guam ecosystem. Methods,,, Postmortem brain specimens were taken from neuropathologically confirmed cases of 13 ALS, 12 AD, 8 HD patients, and 12 age-matched non-neurological controls. BMAA was quantified using a validated fluorescent HPLC method previously used to detect BMAA in patients from Guam. Tandem mass spectrometric (MS) analysis was carried out to confirm the identification of BMAA in neurological specimens. Results,,, We detected and quantified BMAA in neuroproteins from postmortem brain tissue of patients from the United States who died with sporadic AD and ALS but not HD. Incidental detections observed in two out of the 24 regions were analyzed from the controls. The concentrations of BMAA were below what had been reported previously in Chamarro ALS/ Parkinsonism dementia complex patients, but demonstrated a twofold range across disease and regional brain area comparisons. The presence of BMAA in these patients was confirmed by triple quadrupole liquid chromatography/mass spectrometry/mass spectrometry. Conclusions,,, The occurrence of BMAA in North American ALS and AD patients suggests the possibility of a gene/environment interaction, with BMAA triggering neurodegeneration in vulnerable individuals. [source] Microglia as immune effectors of the central nervous system: Expression of cytokines and chemokinesCLINICAL AND EXPERIMENTAL NEUROIMMUNOLOGY, Issue 2 2010Seung U. Kim Abstract Microglia, one of three glial cell types in the central nervous system (CNS), play an important role as resident immunocompetent and phagocytic cells in the CNS in the event of injury and disease. It was del Rio Hortega in 1927 who determined that microglia belong to a distinct glial cell type in the CNS, apart from astrocytes and oligodendrocytes. Since the 1970s, there has been wide recognition that microglia are immune effectors in the CNS that respond to pathological conditions and participate in the initiation and progression of neurological disorders including Alzheimer's disease, Parkinson's disease, multiple sclerosis and acquired immune deficiency syndrome dementia complex by releasing potentially cytotoxic molecules such as pro-inflammatory cytokines, reactive oxygen intermediates, proteinases and complement proteins. There is also evidence to suggest that the microglia are capable of secreting neurotrophic or neuron survival factors on activation through inflammation or injury. In the present review, the current status of knowledge on biology and immunology of microglia is reported. (Clin. Exp. Neuroimmunol. doi: 10.1111/j.1759-1961.2010.00007.x, 2010) [source] | ||||||||||