Alzheimer's disease (AD), the cause of one of the most common types of dementia, is pathologically characterized by cholinergic deficits, extracellular amyloid deposit, intraneuronal neurofibrillary tangles, gliosis, and neuronal and synaptic loss. The primary clinical manifestation of AD is a profound global dementia that is marked by severe amnesia with additional deficits in language, executive functions, attention, and visuospatial and constructional abilities. Molecular genetic studies have identified at least three genes that, when mutated, cause the autosomal dominant, early-onset familial form of the disease The late-onset, most common forms of the disease are likely to be associated with various genetic susceptibility factors. Research on the underlying pathophysiological dysfunction finally disclosed more disease-specific processes. Of particular importance is the identification and characterization of the secretases involved in endoproteolytic processing of β-amyloid precursor protein, the precursor of the amyloid β-peptide(Aβ). It is generally accepted that Aβ plays a pivotal role in the pathogenesis of AD, and that reducing brain Aβ levels may be a disease-modifying strategy. By inhibiting one or both amyloidogenic secretases and immunization with Aβ, neuropathological features of AD can be prevented or alleviated.
Alzheimer Disease* ; Amnesia ; Amyloid ; Amyloid Precursor Protein Secretases ; Brain ; Dementia ; Executive Function ; Genetic Predisposition to Disease ; Gliosis ; Immunization ; Molecular Biology* ; Neurofibrillary Tangles ; Neurons ; Plaque, Amyloid ; Presenilins

Bilateral acoustic neurofibrornatosis or neurofibrornatosis-2 is characterized by bilateral acoustic neurornas and it is thought to be genetically distinct from the neurohbrornatosis-1. Also called von Recklinghausen's neurofibrornatosis. We report 2 patients with neurofibrornatosis-2. Who showed progressive bilateral hearing loss, unsteady gait and headache.Neuroirnaging studies revealed bilateral cerebellopontine angle rnasses and biopsies confirmed the diagnosis.
Acoustics ; Biopsy ; Cerebellopontine Angle ; Diagnosis ; Gait Disorders, Neurologic ; Hearing Loss, Bilateral ; Humans ; Neurofibromatoses*

BACKGROUND: The central nervous system (CNS) is a well-known target site of steroid hormone action. Both the pyramidal neurons of Ammon's horn and the granule cells (GC) of the dentate gyrus, which have a high concentration of glucocorticoid receptors are the major targets for this hormone. Because the hippocampal formation is critically involved in memory and learning, the effects of glucocorticoid on the hippocampus are of particular interest. Chronic administration of high doses of corticosterone has been shown to directly damage to hippocampus, whereas removal of circulating glucocorticoid by adrenalectomy (ADX) may cause selective degeneration of dentate granule cells. Thus corticosterone appears to have two markedly different effects on cells of the hippocampus in rats. METHODS: In the present study, we investigate the changes in the hippocampal structures after bilateral adrenalectomy at various time points. RESULTS: Silver staining procedure selective for damaged neuronal membranes revealed degenerating neurons in dentate gyrus. Argyrophilia was specifically confine to dentate granule cells and was accompanied by the occurrence of pyknotic nuclei as observed in cresyl violet and H & E stained sections. However, on the contrary to the previous reports the neuronal loss in GC layers in dentate gyrus is variable. There were significant differences between individual rats in quantity of argyrophilia. In situ terminal transferase-mediated dUTP-nick end labeling technique (TUNEL) demonstrated that some of the ADX-induced neuronal degeneration was due to a apoptosis-related mechanism. In some of the ADX animals, NADPH-diaphorase positive neurons in the hippocampus found to be selectively lost. The latter finding should be confirmed in the subsequent experiments. CONCLUSION: These results suggest that following ADX, some of the GC undergoes neurodegeneration via apoptotic mechanism. And the present data strengthen the evidence pointing to the critical role of corticosteroids in maintaining the structural inte.
Adrenal Cortex Hormones ; Adrenalectomy* ; Animals ; Apoptosis ; Central Nervous System ; Corticosterone ; Dentate Gyrus ; Hippocampus ; Learning ; Membranes ; Memory ; Neurons* ; Rats* ; Receptors, Glucocorticoid ; Silver Staining ; Viola

Acute carbon monoxide (CO) poisoning primarily affects the central nervous system(CNS), and survivors of severe CO poisoning often suffer permanent neuropsychiatric sequelae. The most widely recognized long-term sequelae of acute CO poisoning are neurobehavioral abnormalities varying from mild personality changes, difficulty in learning and behavioral problems, to irreversible dementia. The mechanisms of these processes are poorly understood although same investigators have suggested the involvement of CO-mediated brain cerebral mitochondrial energy metabolism. Since cellular injury by almost any mechanism has the potential to accelerate free radical reactions, it appears that reactive oxygen species (ROS) may have a critical role in CO-induced brain injury. There is evidence in rats that CO vulnerable brain regions show increased production of hydrogen peroxide and hydroxyl radical after acute poisoning. On the other hand, recent evidence suggests that the novel free radical neuromodulator, nitric oxide (NO), mediates NMDA receptor-linked excitotoxicity, and that neurons that contain NO synthase (NOS) are themselves spared from NMDA and NO toxic effects. NADPH-diaphorase neurons preferentially survive in the striatum in patients with Huntington's disease, Alzheimer's disease, and relatively spared in experimental models of brain damage due to ischemia or NMDA-mediated neurotoxins. In contrast to these findings, current experiment revealed that some of NOS neuons underwent degenerative changes several days after CO exposure. Moreover, oxidative stress itself could be a mediator of apoptosis much as programmed cell death associated with experimental focal cerebral ischemia in rats. Likewise apoptosis after CO poisoning might be a cause of cell death in addition to conventional necrotic cell death. Subsequent studies are needed to verify this conjecture, which eventually can elucidate the 'biphasic' clinical features of CO poisoning.
Alzheimer Disease ; Animals ; Apoptosis ; Brain Injuries ; Brain Ischemia ; Brain* ; Carbon Monoxide Poisoning* ; Carbon Monoxide* ; Carbon* ; Cell Death ; Dementia ; Energy Metabolism ; Hand ; Humans ; Huntington Disease ; Hydrogen Peroxide ; Hydroxyl Radical ; Ischemia ; Learning ; Models, Theoretical ; N-Methylaspartate ; Neurons* ; Neurotoxins ; Neurotransmitter Agents ; Nitric Oxide Synthase* ; Nitric Oxide* ; Oxidative Stress ; Poisoning ; Rats* ; Reactive Oxygen Species ; Research Personnel ; Survivors

Alzheimer's disease (AD) is the leading cause of dementia, and the most prevalent neurodegenerative disease in the elderly. The prevalence of AD is predicted to rise as life expectancy grows across populations. The exact cause of this devastating disease is still unknown; however, it is an aging-related multi-factorial disorder, and growing evidence supports the contribution of modifiable environmental factors to unmodifiable factors such as gene and ageing itself. The recent advancement of methodologies and techniques for early diagnosis of AD facilitates the investigation of strategies to reduce the risk for AD progression in the earliest stages of the disease. Pharmacological attempts at curing, halting or modifying it have, by and large, been unsuccessful, and no breakthrough is seen in the near future. However, a lot of elements that seem to contribute to the disease such as risk factors have been identified, mainly from epidemiological and basic research studies. Many of these are amenable to lifestyle modification. Therefore, prevention in the preclinical stage is likely the most effective way to decrease the incidence of this age-associated dreadful neurodegenerative condition, and its associated burden for individuals and society. We provide an overview of modifiable risk factors for AD along with the supporting evidence.
Alzheimer Disease/epidemiology/*prevention & control ; Cognitive Therapy ; Dietary Supplements ; Health Behavior ; Humans ; Mind-Body Therapies ; Motor Activity ; Risk Factors

Vitamin D is not a true vitamin but a fat-soluble steroid prohormone that has long been known for its important and diverse role in the biological system. Many studies have revealed that vitamin D deficiency is linked with an increased risk of autoimmune diseases, cardiovascular diseases, cancers, type II diabetes and infectious diseases. Vitamin D3 is transformed to its active form, 1, 25-dihydroxyvitamin D3, through metabolisms in the liver and kidney. 1, 25-dihydroxyvitamin D3 interacts with its vitamin D receptor, and the brain is now known to have vitamin D receptors and 1alpha-hydroxylase. Several lines of evidences suggest vitamin D deficiency is associated with cognitive impairment and dementia, however, its position in cognitive function is still in its infancy. Vitamin D deficiency is a reversible condition and can be easily treated with supplements. Randomized controlled trials of vitamin D supplementation in patients with neurodegenerative conditions are needed.
Autoimmune Diseases ; Brain ; Cardiovascular Diseases ; Cholecalciferol ; Cognition ; Communicable Diseases ; Dementia ; Humans ; Kidney ; Liver ; Receptors, Calcitriol ; Vitamin D ; Vitamin D Deficiency ; Vitamins

The selective vulnerability of the basal ganglia to carbon monoxide(CO) is well recognized. And hyperbaric oxygen therapy(HBO) has long been accepted as a primary treatment for CO poisoning; however, the mechanism of action and objective methods to assess the therapeutic efhcacy of HBO have not been fully established. To evaluate the effect of HBO on the neurotransmitter changes in CO poisoning the striatal dopamine and its metabolites were measured in CO-intoxicated and HBO treated rats by high performance liquid chromatograpy with electrochemical detection. Male SpragueDawley rats, weighing 250-350 g were exposed to 4,500 ppm CO for 30 minutes and a group of them was treated with HBO(3 ATA, 30 miutes). The neostriatum of the rats were obtained and investigated according to the various time lapse after the cessation of CO exposure or the completion of HBO, The results are as follows: 1. The application of the routine HBO to the normal rat did not affect the levels of striatal neurotransmitters. 2. The concentration of striatal DA was markedly increased in CO-intoxicated rat during acute phase and it was reversed by HBO. But the effect did not last more than 24 hours. 3. In the delayed phase of experiment, the concentration of striatal DA tended to be decreased, which was partially thought to be due to the striatal injury, damage of striatonigral pathway or neuronal loss of substantia nigra by C0-intoxication.These results suggest that dopaminergic system might be implicated both in the pathogenesis of C0-induced striatal injury and the therapeutic efficacy of HB0.
Animals ; Basal Ganglia ; Carbon Monoxide* ; Carbon* ; Dopamine ; Humans ; Hyperbaric Oxygenation* ; Male ; Neostriatum ; Neurons ; Neurotransmitter Agents* ; Oxygen ; Poisoning ; Rats* ; Substantia Nigra

No abstract available.
Diagnosis* ; Encephalitis, Herpes Simplex* ; Herpes Simplex*

Epilepsy with an onset of initial episode in adult life is not a rare event. It is generaly considered that the onset of seizure after early adulthood may turn out to be an ominous sign and should be investigated thoroughlyly to rule out an organic brain lesion. The present study of 206 patients with epilepsy of late onset (over 20 years of age), who admitted to or were consulted Department of Neurology, Seoul National University Hospital from January 1982 to December 1985, was undertaken to seek treatable causes and re-evaluate the relationship between clinical evaluation, electroencephalography and computerized tomography of the brain. Patients'ages ranged from 20 to 74.132 were men and 74, women (64% and 36%, respectively). Major causes were infectious or inflammatory origin (45.2%) and cerebrovascular disorders (21.8%). Causes remained unknown in 14.2%. Comparison of the CT findings with EEG showed a close relationship between the local EEG slowing and the focal CT abnormality. Therapeutic responses to antiepileptic drugs were not favorable in patients with encephalitis or meningoencephalitis.
Adult ; Anticonvulsants ; Brain ; Cerebrovascular Disorders ; Electroencephalography ; Encephalitis ; Epilepsy* ; Female ; Humans ; Male ; Meningoencephalitis ; Neurology ; Seizures ; Seoul

To investigate the factors affecting the development of seizures after spontaneously occurred lobar intracerebral hemorrhage (ICH) such as size, location, and onset age of hemorrhage and clinical feature of those seizures, we analyzed 34 patient with spontaneously occurred lobar ICH in the respect of seizures retrospectively. From October 1991 to March 1994, 41 patient were admitted to the Chungbuk National University Hospital with spontaneously occurred lobar ICH. Among them, 2 patients died within 7days after ICH and 5 patients could not be followed adequately by any means. Finally we analyzed 34 patients whom we followed up at least 3 yrs except 2 patients (one had seizures at 7 month and 8 month after ICH then lost follow up; the other with no seizure died 25 months after ICH). Seizures occurred in 8 out of 34 (23.5%) patients, 2patients within 2 weeks, 4within 1 year, and 2 within 3years. Three patients showed generalized tonic clonic seizure and 5 partial seizure with secondary generalization. All patients with seizures were satisfactorily managed by single antiepileptic drug. Their EEG findings are as follows, 1 patient normal; 1 generalized slowing; 4 localized slowing; 2 localized spikes. Size (p = 0.74), location (p = 0.52), and age of onset (p = 0.74) of lobar ICH are not different between patients with seizures and ones without seizures. This study suggests that medically controllable seizures develop in relatively high portion of patients with spontaneous lobar ICH could not predict the occurrence of epileptic seizures in this group of patients.
Age of Onset ; Cerebral Hemorrhage* ; Chungcheongbuk-do ; Electroencephalography ; Epilepsy ; Follow-Up Studies ; Generalization (Psychology) ; Hemorrhage ; Humans ; Retrospective Studies ; Seizures*