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1.
Clin Exp Ophthalmol ; 47(4): 469-477, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30414237

RESUMO

IMPORTANCE: Open-globe injuries (OGI) are a leading cause of monocular blindness world-wide with considerable cost to the individual and society. BACKGROUND: To characterize the epidemiology, severity and outcomes of OGI treated at a major ophthalmology centre in New Zealand. DESIGN: Retrospective study. PARTICIPANTS: A total of 385 eyes of 381 patients over a 10-year period. METHODS: Eligible patients were identified using diagnosis and surgery codes on hospital discharge summaries. Clinical notes were reviewed to determine patient demographics, injury details, treatments and outcomes. MAIN OUTCOME MEASURES: Complications of injury, visual acuity at 3 months and final follow-up, and final status of the eye. RESULTS: The estimated annual incidence of OGI was 2.8 per 100 000. Working-age males predominated but age at injury ranged from 9 months to 90 years. Maori and Pacific peoples were over-represented. Injuries were severe with 58.7% presenting with vision of hand movements or worse. Penetrating injuries (56.4%) were most common, followed by globe ruptures (35.6%). Major complications included retinal detachment (15.8%), enucleation/evisceration (9.1%), phthisis bulbi (9.9%), endophthalmitis (2.6%) and sympathetic ophthalmia (0.26%). Despite the injury severity, 46% of eyes achieved final BCVA of ≥6/12. The Ocular Trauma Score (OTS) was a useful prognostic tool for stratifying severity of injury and predicting visual outcome (Fisher's exact test P < 0.001). CONCLUSIONS AND RELEVANCE: The incidence and severity of OGI in NZ are comparable to global statistics. Surgical repair can effectively recover vision, predicted well by the OTS. We identified at-risk groups to target with education and prevention strategies.


Assuntos
Oftalmopatias/epidemiologia , Ferimentos Oculares Penetrantes/epidemiologia , Acuidade Visual/fisiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Ferimentos Oculares Penetrantes/fisiopatologia , Ferimentos Oculares Penetrantes/cirurgia , Feminino , Seguimentos , Humanos , Incidência , Lactente , Masculino , Pessoa de Meia-Idade , Morbidade , Nova Zelândia/epidemiologia , Procedimentos Cirúrgicos Oftalmológicos , Prognóstico , Estudos Retrospectivos , Índice de Gravidade de Doença , Distribuição por Sexo
2.
FASEB J ; 20(3): 419-25, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16507759

RESUMO

To date there is no accepted clinical diagnostic test for Parkinson's disease (PD) based on biochemical analysis of blood or cerebrospinal fluid (CSF). alpha-Synuclein (alpha-syn) protein has been linked to the pathogenesis of PD with the discovery of mutations in the gene encoding alpha-syn in familial cases with early-onset PD. Lewy bodies and Lewy neurites, which constitute the main pathological features in the brains of patients with sporadic PD and dementia with Lewy bodies, are formed by the conversion of soluble monomers of alpha-syn into insoluble aggregates. We recently reported the presence of alpha-syn in normal human blood plasma and in postmortem CSF. Here, we investigated whether alpha-syn can be used as a biomarker for PD. We have developed a novel ELISA method that detects only oligomeric "soluble aggregates" of alpha-syn. Using this ELISA, we report the presence of significantly elevated (P=0.002) levels of oligomeric forms of alpha-syn in plasma samples obtained from 34 PD patients compared with 27 controls; 52% (95% confidence intervals 0.353-0.687) of the PD patients displayed signals >0.5 OD with our ELISA assay in comparison to only 14.8% (95% confidence intervals 0.014-0.281) for the control cases. An analysis of the test's diagnostic value revealed a specificity of 0.852 (95% confidence intervals 0.662-0.958), sensitivity of 0.529 (95% confidence intervals 0.351-0.702) and a positive predictive value of 0.818 (95% confidence intervals 0.597-0.948). These observations offer new opportunities for developing diagnostic tests for PD and related diseases and for testing therapeutic agents aimed at preventing or reversing the aggregation of alpha-syn.


Assuntos
Doença de Parkinson/sangue , alfa-Sinucleína/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Biopolímeros , Cromatografia em Gel , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/líquido cefalorraquidiano , Valor Preditivo dos Testes , Proteínas Recombinantes de Fusão/química , Sensibilidade e Especificidade , alfa-Sinucleína/líquido cefalorraquidiano , alfa-Sinucleína/química
3.
FASEB J ; 17(13): 1945-7, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14519670

RESUMO

Parkinson's disease (PD) and other related disorders are characterized by the accumulation of fibrillar aggregates of alpha-synuclein protein (alpha-syn) inside brain cells. It is likely that the formation of alpha-syn aggregates plays a seminal role in the pathogenesis of at least some of these diseases, because two different mutations in the gene encoding alpha-syn have been found in inherited forms of PD. alpha-Syn is mainly expressed by neuronal cells and is generally considered to exist as a cytoplasmic protein. Here, we report the unexpected identification of alpha-syn in conditioned culture media from untransfected and alpha-syn-transfected human neuroblastoma cells, as well as in human cerebrospinal fluid and blood plasma. The method used was immunocapture by using anti-alpha-syn antibodies coupled to magnetic beads, followed by detection on Western blots. In all cases, alpha-syn was identified as a single 15 kDa band, which co-migrated with a recombinant form of the protein and reacted with five different antibodies to alpha-syn. Our findings suggest that cells normally secrete alpha-syn into their surrounding media, both in vitro and in vivo. The detection of extracellular alpha-syn and/or its modified forms in body fluids, particularly in human plasma, offers new opportunities for the development of diagnostic tests for PD and related diseases.


Assuntos
Proteínas do Tecido Nervoso/análise , Western Blotting , Espaço Extracelular/química , Humanos , Modelos Biológicos , Proteínas do Tecido Nervoso/sangue , Proteínas do Tecido Nervoso/líquido cefalorraquidiano , Neurônios/metabolismo , Doença de Parkinson/etiologia , Sinucleínas , Células Tumorais Cultivadas , alfa-Sinucleína
4.
Clin Ophthalmol ; 9: 745-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25987832

RESUMO

PURPOSE: Virtual glaucoma clinics allow rapid, reliable patient assessment but the service should be acceptable to patients and concordance with treatment needs to be maintained with adequate patient education. This study compares experiences and understanding of patients reviewed via the virtual clinic versus the standard clinic by way of an extended patient satisfaction questionnaire (PSQ). PATIENTS AND METHODS: One hundred PSQs were given to consecutive patients attending glaucoma clinics in October 2013. All 135 patients reviewed via the virtual clinic from April 2013 until August 2013 were sent postal PSQs in September 2013. Data were obtained for demographics, understanding of glaucoma, their condition, satisfaction with their experience, and quality of information. Responses were analyzed in conjunction with the clinical records. RESULTS: Eighty-five percent of clinic patients and 63% of virtual clinic patients responded to the PSQ. The mean satisfaction score was over 4.3/5 in all areas surveyed. Virtual clinic patients' understanding of their condition was very good, with 95% correctly identifying their diagnosis as glaucoma, 83% as ocular hypertension and 78% as suspects. There was no evidence to support inferior knowledge or self-perceived understanding compared to standard clinic patients. Follow-up patients knew more about glaucoma than new patients. Over 95% of patients found our information leaflet useful. Forty percent of patients sought additional information but less than 20% used the internet for this. CONCLUSION: A substantial proportion of glaucoma pathway patients may be seen by non-medical staff supervised by glaucoma specialists via virtual clinics. Patients are accepting of this format, reporting high levels of satisfaction and non-inferior knowledge to those seen in standard clinics.

5.
BMJ Case Rep ; 20152015 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-25564592

RESUMO

A 64-year-old man presented with a 2-day history of acute onset painless left ptosis. He had no other symptoms; importantly pupils were equal and reactive and eye movements were full. There was no palpable mass or swelling. He was systemically well with no headache, other focal neurological signs, or symptoms of fatigue. CT imaging showed swelling of the levator palpebrae superioris suggestive of myositis. After showing no improvement over 5 days the patient started oral prednisolone 30 mg reducing over 12 weeks. The ptosis resolved quickly and the patient remains symptom free at 6 months follow-up. Acute ptosis may indicate serious pathology. Differential diagnoses include a posterior communicating artery aneurysm causing a partial or complete third nerve palsy, Horner's syndrome, and myasthenia gravis. A careful history and examination must be taken. Orbital myositis typically involves the extraocular muscles causing pain and diplopia. Isolated levator myositis is rare.


Assuntos
Blefaroptose/diagnóstico , Pálpebras/patologia , Músculo Esquelético/patologia , Miosite Orbital/diagnóstico , Blefaroptose/tratamento farmacológico , Blefaroptose/etiologia , Diagnóstico Diferencial , Diplopia/diagnóstico , Movimentos Oculares , Síndrome de Horner/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/diagnóstico , Músculos Oculomotores , Doenças do Nervo Oculomotor/diagnóstico , Miosite Orbital/tratamento farmacológico , Miosite Orbital/etiologia , Prednisolona/uso terapêutico
6.
Biol Psychiatry ; 54(11): 1222-33, 2003 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-14643090

RESUMO

BACKGROUND: The etiology of dementia that occurs in patients with schizophrenia is not well understood. Nicotinic acetylcholine receptors have been implicated in cognitive function, and deficits in these receptors have been reported in schizophrenia. METHODS: The present study investigates possible associations of nicotinic receptor subunit expression in the dorsal lateral prefrontal cortex, an area known to be affected in schizophrenia, and dementia rating. RESULTS: alpha7 immunoreactivity was reduced by 20% to 28% and [(3)H]epibatidine binding was increased twofold in groups of patients with schizophrenia compared to normal control subjects matched for age, postmortem delay, and low levels of brain nicotine and cotinine. In contrast, no significant differences in alpha4, alpha3, or beta2 immunoreactivity or alpha7 messenger RNA expression were observed in schizophrenia patients compared with control subject values. Clinical dementia ratings in patients with schizophrenia were correlated with neither [(3)H]epibatidine binding nor nicotinic receptor subunit expression. CONCLUSIONS: These data indicate no relationship between the trend for reduced neocortical alpha7 subunit protein expression in schizophrenia and dementia. Further investigations are required to establish whether the reduction in alpha7 protein in the dorsal lateral prefrontal cortex is associated with clinical features other than dementia in schizophrenia.


Assuntos
Demência/metabolismo , Córtex Pré-Frontal/metabolismo , Receptores Nicotínicos/biossíntese , Esquizofrenia/metabolismo , Idoso , Idoso de 80 Anos ou mais , Compostos Bicíclicos Heterocíclicos com Pontes/metabolismo , Estudos de Casos e Controles , Cotinina/metabolismo , Demência/complicações , Demência/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nicotina/metabolismo , Escalas de Graduação Psiquiátrica , Piridinas/metabolismo , RNA Mensageiro/biossíntese , Ensaio Radioligante , Esquizofrenia/complicações , Esquizofrenia/diagnóstico , Índice de Gravidade de Doença , Fumar
7.
J Mol Neurosci ; 18(3): 211-22, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12059039

RESUMO

Neuronal nicotinic receptor binding sites as well as mRNA levels encoding for subunits alpha4, beta2, and alpha7 were analysed in 3-mo-old transgenic mice generated with a neuronal overexpression of human acetylcholinesterase and in age-matched controls. The acetylcholinesterase transgenic mice display progressive cognitive impairment in spatial learning and memory. We here report a significantly increased [3H]epibatidine and [125I]alphabungarotoxin binding in the cortex and the caudate putamen of these mice. Quantitativein situ hybridization showed significant upregulation of mRNA corresponding to the nicotinic receptor subunits alpha4, beta2, and alpha7 in various brain regions in the transgenic mice compared to nontransgenic controls. Our results suggest that disruption of balanced cholinergic transmission by constitutive overexpression of acetylcholinesterase is accompanied by variable upregulation of several nicotinic receptor subtypes, in particular these associated with cholinergic terminals participating in compensatory response.


Assuntos
Acetilcolinesterase/metabolismo , Neurônios/fisiologia , Receptores Nicotínicos/metabolismo , Regulação para Cima/fisiologia , Acetilcolinesterase/genética , Animais , Autorradiografia , Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Compostos Bicíclicos Heterocíclicos com Pontes/metabolismo , Bungarotoxinas/metabolismo , Butirilcolinesterase/metabolismo , Feminino , Humanos , Hibridização In Situ , Aprendizagem/fisiologia , Masculino , Memória/fisiologia , Camundongos , Camundongos Transgênicos , Neurônios/citologia , Agonistas Nicotínicos/metabolismo , Subunidades Proteicas , Piridinas/metabolismo , Receptores Nicotínicos/genética , Estatística como Assunto , Receptor Nicotínico de Acetilcolina alfa7
8.
J Neurol Sci ; 225(1-2): 39-49, 2004 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-15465084

RESUMO

Alzheimer's disease (AD) and dementia with Lewy bodies (DLB) are common forms of dementia in the elderly. The neuropathology of AD and DLB is related to cholinergic dysfunctions, and both alpha4 and alpha7 nicotinic acetylcholine receptor (nAChR) subunits are decreased in several brain areas in both diseases. In this immunohistochemical study, we compared neuronal and astroglial alpha4 and alpha7 subunits in AD, DLB and age-matched controls in the hippocampal formation. The numbers of alpha4 reactive neurons were decreased in layer 3 of the entorhinal cortex of AD and DLB, whereas those of alpha7 reactive neurons were decreased in layer 2 of the subiculum of AD and DLB and in layer 3 of the entorhinal cortex of DLB. In contrast, the intensity of alpha7 reactive neuropil was significantly higher in AD than in controls or DLB in a number of areas of the hippocampus (CA3/4 and stratum granulosum), subiculum and entorhinal cortex. An increase in alpha7 immunoreactivity in AD was also associated with astrocytes. The number of astrocytes double-labelled with alpha7 and glial fibrillary acidic protein (GFAP) antibodies was increased in most areas of the hippocampus and entorhinal cortex in AD compared with controls and DLB. Increased astrocyte alpha7 nAChRs in AD may be associated with inflammatory mechanisms related to degenerative processes specific to this disease.


Assuntos
Doença de Alzheimer/metabolismo , Astrócitos/metabolismo , Doença por Corpos de Lewy/metabolismo , Neurônios/metabolismo , Receptores Nicotínicos/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Encéfalo/citologia , Encéfalo/metabolismo , Estudos de Casos e Controles , Contagem de Células/métodos , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Imuno-Histoquímica/métodos , Doença por Corpos de Lewy/patologia , Masculino , Receptor Nicotínico de Acetilcolina alfa7
9.
Neurobiol Dis ; 23(2): 481-9, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16759874

RESUMO

Antibodies raised against human alpha2-6 and beta2-4 nicotinic receptor subunits were utilized to fractionate (3)H-epibatidine binding in human temporal cortex and striatum. The predominant receptor subtypes in both regions contained alpha4 and beta2 subunits. In normal cortex, 10% of binding was also associated with alpha2 subunits, whereas in the striatum, contributions by alpha6 (17%) and beta3 (23%) were observed. Minimal binding (< or =5%) was associated with alpha3. In Alzheimer's disease and dementia with Lewy bodies, cortical loss of binding was associated with reductions in alpha4 (50%, P < 0.01) and beta2 (30-38%, P < 0.05). In Parkinson's disease and dementia with Lewy bodies, striatal deficits in alpha6 (91 and 59% respectively, P < 0.01) and beta3 (72 and 75%, P < 0.05) tended to be greater than for alpha4 and beta2 (50-58%, P < 0.05). This study demonstrates distinct combinations of subunits contributing to heteromeric nicotinic receptor binding in the human brain that are area/pathway specific and differentially affected by neurodegeneration.


Assuntos
Doença de Alzheimer/patologia , Corpo Estriado/patologia , Corpos de Lewy/patologia , Doença de Parkinson/patologia , Receptores Nicotínicos/deficiência , Lobo Temporal/patologia , Idoso , Idoso de 80 Anos ou mais , Sequência de Aminoácidos , Autopsia , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Fragmentos de Peptídeos/imunologia , Receptores Nicotínicos/química , Receptores Nicotínicos/genética
10.
Glia ; 41(2): 207-11, 2003 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-12509811

RESUMO

Alzheimer's disease (AD) and dementia with Lewy bodies (DLB) are common forms of dementia in the elderly associated with cholinergic dysfunction, including reductions in nicotinic acetylcholine receptors (nAChRs). In AD, astrocytes are implicated in the formation of senile plaques, one of the core pathological features. Using immunohistochemistry, we have investigated astrocytic expression of the two major nicotinic receptor alpha subunits in the human hippocampus and entorhinal cortex. alpha7, but not alpha4, subunit immunoreactivity was associated with astrocytes. An increase in the proportion of astrocytes expressing alpha7 immunoreactivity was observed in AD compared with age-matched controls. A similar increase was not evident in DLB. Elevated alpha7 nAChRs on astrocytes in AD may contribute to alterations in calcium homeostasis and nitric oxide production, which in turn could affect beta-amyloid-mediated inflammatory processes in AD.


Assuntos
Doença de Alzheimer/metabolismo , Astrócitos/metabolismo , Córtex Entorrinal/metabolismo , Hipocampo/metabolismo , Receptores Nicotínicos/metabolismo , Regulação para Cima/fisiologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Astrócitos/citologia , Cálcio/metabolismo , Córtex Entorrinal/patologia , Córtex Entorrinal/fisiopatologia , Hipocampo/patologia , Hipocampo/fisiopatologia , Homeostase/fisiologia , Humanos , Imuno-Histoquímica , Doença por Corpos de Lewy/metabolismo , Doença por Corpos de Lewy/patologia , Doença por Corpos de Lewy/fisiopatologia , Óxido Nítrico/metabolismo , Placa Amiloide/metabolismo , Receptor Nicotínico de Acetilcolina alfa7
11.
Eur J Neurosci ; 19(10): 2703-10, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15147304

RESUMO

Ten days treatment with nicotine reduced insoluble amyloid A beta 1-40 and Alpha beta 1-42 peptides by 80% in the cortex of 9-month-old APPsw mice, which is more than that observed in 14.5-month-old mice following nicotine treatment for 5.5 months. A reduction in A beta associated with cerebral vessels was observed in addition to that deposited as parenchymal plaques after 5.5 months treatment. The diminution in A beta peptides observed was not accompanied by changes in brain alpha, beta or gamma secretase-like activities, NGF or BDNF protein expression measured in brain homogenates. A significant increase in sAPP was observed after nicotine treatment of SH-SY5Yneuroblastoma cells that could be blocked by the nicotinic antagonist mecamylamine. Attenuation of elevated [(125)I]-alpha bungarotoxin binding (alpha 7) in APPsw mice was observed after 5.5 months nicotine treatment. Both these observations suggest that the reduction in insoluble A beta by nicotine might be in part mediated via the alpha 7 nicotinic receptor. Further studies are required to identify potential mechanisms of the nicotine's amyloid-reducing effect.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Vasos Sanguíneos/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Artérias Cerebrais/efeitos dos fármacos , Nicotina/administração & dosagem , Fatores Etários , Secretases da Proteína Precursora do Amiloide , Peptídeos beta-Amiloides/análise , Peptídeos beta-Amiloides/sangue , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Ácido Aspártico Endopeptidases , Western Blotting/métodos , Encéfalo/metabolismo , Química Encefálica , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Bungarotoxinas/farmacocinética , Linhagem Celular Tumoral , Artérias Cerebrais/metabolismo , Esquema de Medicação , Embrião de Mamíferos , Endopeptidases/metabolismo , Transportador de Glucose Tipo 1 , Humanos , Imuno-Histoquímica/métodos , Isótopos de Iodo/farmacocinética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas de Transporte de Monossacarídeos/metabolismo , Fator de Crescimento Neural/metabolismo , Neuroblastoma , Nicotina/farmacologia , Fragmentos de Peptídeos/análise
12.
J Neurochem ; 81(3): 655-8, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12065674

RESUMO

Alzheimer's disease neuropathology is characterised by beta-amyloid plaques and neurofibrillary tangles. Inhibition of beta-amyloid accumulation may be essential for effective therapy in Alzheimer's disease. In this study we have treated transgenic mice carrying the Swedish mutation of human amyloid precursor protein [Tg(Hu.APP695.K670N-M671L)2576], which develop brain beta-amyloid deposits, with nicotine in drinking fluid (200 microg/mL) from 9-14.5 months of age (5.5 months). A significant reduction in amyloid beta peptide 1-42 positive plaques by more than 80% (p < 0.03) was observed in the brains of nicotine treated compared to sucrose treated transgenic mice. In addition, there was a selective reduction in extractable amyloid beta peptides in nicotine treated mice; cortical insoluble 1-40 and 1-42 peptide levels were lower by 48 and 60%, respectively (p < 0.005), whilst there was no significant change in soluble 1-40 or 1-42 levels. The expression of glial fibrillary acidic protein was not affected by nicotine treatment. These results indicate that nicotine may effectively reduce amyloid beta peptide aggregation in brain and that nicotinic drug treatment may be a novel protective therapy in Alzheimer's disease.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Nicotina/administração & dosagem , Placa Amiloide/efeitos dos fármacos , Administração Oral , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/análise , Peptídeos beta-Amiloides/biossíntese , Animais , Astrócitos/metabolismo , Astrócitos/patologia , Química Encefálica , Contagem de Células , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Modelos Animais de Doenças , Progressão da Doença , Esquema de Medicação , Feminino , Proteína Glial Fibrilar Ácida/biossíntese , Hipocampo/química , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Transgênicos , Condutos Olfatórios/química , Fragmentos de Peptídeos/análise , Fragmentos de Peptídeos/biossíntese , Placa Amiloide/metabolismo , Placa Amiloide/patologia , Fatores Sexuais , Resultado do Tratamento
13.
Conscious Cogn ; 11(3): 461-74, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12435378

RESUMO

Disturbances of consciousness, including fluctuations in attention and awareness, are a common and clinically important symptom in dementia with Lewy bodies (DLB). In the present study we investigate potential mechanisms of such disturbances of consciousness (DOC) in a clinicopathological study evaluating specific components of the cholinergic system. [3H]Epibatidine binding to the high-affinity nicotinic receptor in the temporal cortex (Brodmann's areas 20 and 36) differentiated DLB cases with and without DOC, being 62-66% higher in those with DOC (F=4.5,p=.025). The were no differences between DLB patients with or without DOC in 125I-labeled alpha-bungaratoxin binding to the low-affinity nicotinic receptor, [3H]pirenzepine binding to the muscarinic M1 receptor, or in choline acetyltransferase activity. These findings provide support for the hypothesis that cholinergic activity is an important neural correlate if consciousness and suggest a mechanism of DOC in DLB involving alterations in the nicotinic receptor, composed of predominantly alpha4 and beta2 subunits.


Assuntos
Transtornos da Consciência/etiologia , Doença por Corpos de Lewy/complicações , Doença por Corpos de Lewy/psicologia , Receptores Nicotínicos/fisiologia , Lobo Temporal/patologia , Idoso , Bungarotoxinas , Transtornos da Consciência/fisiopatologia , Feminino , Humanos , Masculino
14.
Mol Cell Neurosci ; 20(2): 354-65, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12093166

RESUMO

The nicotinic (nAChRs) and muscarinic (mAChRs) acetylcholine receptors and acetylcholinesterase (AChE) activity were studied in the brains of APP(SWE) transgenic mice (Tg+) and age-matched nontransgenic controls (Tg-) that were between 4 and 19 months of age. A significant increase in the binding of 125I-labeled alpha-bungarotoxin (alpha7 nAChRs) was observed in most brain regions analyzed in 4-month-old Tg+ mice, preceding learning and memory impairments and amyloid-beta (Abeta) pathology. The enhanced alpha7 receptor binding was still detectable at 17-19 months of age. Increase in [3H]cytisine binding (alpha4beta2 nAChRs) was measured at 17-19 months of age in Tg+ mice, at the same age when the animals showed heavy Abeta pathology. No significant changes in [3H]pirenzepine (M1 mAChRs) or [3H]AFDX 384 (M2 mAChRs) binding sites were found at any age studied. The upregulation of the nAChRs probably reflects compensatory mechanisms in response to Abeta burden in the brains of Tg+ mice.


Assuntos
Doença de Alzheimer/genética , Peptídeos beta-Amiloides/biossíntese , Precursor de Proteína beta-Amiloide/genética , Encéfalo/metabolismo , Neurônios/metabolismo , Receptores Nicotínicos/metabolismo , Regulação para Cima/genética , Acetilcolinesterase/metabolismo , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Sítios de Ligação/genética , Encéfalo/patologia , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Feminino , Deficiências da Aprendizagem/genética , Deficiências da Aprendizagem/metabolismo , Deficiências da Aprendizagem/fisiopatologia , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/patologia , Fragmentos de Peptídeos/metabolismo , Placa Amiloide/genética , Placa Amiloide/metabolismo , Placa Amiloide/patologia , RNA Mensageiro/metabolismo , Ensaio Radioligante , Receptores Muscarínicos/metabolismo , Receptores Nicotínicos/genética , Receptor Nicotínico de Acetilcolina alfa7
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