Characterization of the nigroestriatal system in a sample of patients with amyotrophic lateral sclerosis.

BACKGROUND: The coexistence of amyotrophic lateral sclerosis (ALS) with clinical forms of Parkinson disease (PD), although uncommon, is found to a greater degree than one would expect by chance. The pathological mechanisms of ALS and PD are still not fully understood, and the coexistence of these two diseases suggests that they could share mechanisms in common. OBJECTIVE: Here we present a sample of patients with clinically definitive or probable ALS who were evaluated with single-photon emission computed tomography SPECT/TRODAT and compared with non-ALS controls. METHODS: Patients with clinically definite or probable ALS were assessed with the amyotrophic lateral sclerosis functional rating scale (ALSFRS) to define severity and had their demographic data collected. The TRODAT results of patients with ALS were compared with those of patients with a diagnosis of PD with less than 10 years of duration, and with patients with a diagnosis of others movement disorders not associated with neurodegenerative diseases. RESULTS: A total of 75% of patients with ALS had TRODAT results below the levels considered normal; that was also true for 25% of the patients in the control group without neurodegenerative disease, and for 100% of the patients in the PD group. A statistically significant difference was found between patients with ALS and the control group without neurodegenerative disease in the TRODAT values < 0.05. CONCLUSIONS: Our study fits with the neuropathological and functional evidence that demonstrates the existence of nigrostriatal dysfunction in patients with ALS. Further research to better understand the role of these changes in the pathophysiological process of ALS needs to be performed.

ANTECEDENTES: A coexistência da esclerose lateral amiotrófica (ELA) com formas clínicas da doença de Parkinson (DP), embora incomum, é encontrada em um grau maior do que seria esperado ao acaso. Os mecanismos patológicos da ELA e da DP ainda não são totalmente compreendidos e a coexistência dessas duas doenças sugere que elas podem compartilhar mecanismos em comum. OBJETIVO: Apresentamos uma amostra de pacientes com ELA clinicamente definida ou provável que foram avaliados com tomografia computadorizada por emissão de fóton único (SPECT)/TRODAT e comparados com controles sem ELA. MéTODOS: Pacientes com ELA clinicamente definida ou provável foram avaliados com a escala funcional de esclerose lateral amiotrófica (ALSFRS) para definir a gravidade e foram coletados os seus dados demográficos. Os resultados do TRODAT de pacientes com ELA foram comparados com aqueles de pacientes com diagnóstico de DP com menos de 10 anos de duração e com pacientes com diagnóstico de outros distúrbios do movimento não associados a doenças neurodegenerativas. RESULTADOS: Um total de 75% dos pacientes com ELA apresentou resultados de TRODAT abaixo dos níveis considerados normais; 25% no grupo controle sem doença neurodegenerativa e 100% no grupo DP. Uma diferença estatisticamente significativa foi encontrada entre os pacientes com ELA e o grupo controle sem doença neurodegenerativa nos valores de TRODAT p < 0,05. CONCLUSõES: Nosso estudo está de acordo com as evidências neuropatológicas e funcionais que demonstram a existência de disfunção nigroestriatal em pacientes com ELA. Mais pesquisas para entender melhor o papel dessas mudanças no processo fisiopatológico da ELA precisam ser realizadas.

Characterization of the nigroestriatal system in a sample of patients with amyotrophic lateral sclerosis / Caracterização do sistema nigroestriatal em uma amostra de pacientes com esclerose lateral amiotrófica

Abstract Background The coexistence of amyotrophic lateral sclerosis (ALS) with clinical forms of Parkinson disease (PD), although uncommon, is found to a greater degree than one would expect by chance. The pathological mechanisms of ALS and PD are still not fully understood, and the coexistence of these two diseases suggests that they could share mechanisms in common. Objective Here we present a sample of patients with clinically definitive or probable ALS who were evaluated with single-photon emission computed tomography SPECT/TRODAT and compared with non-ALS controls. Methods Patients with clinically definite or probable ALS were assessed with the amyotrophic lateral sclerosis functional rating scale (ALSFRS) to define severity and had their demographic data collected. The TRODAT results of patients with ALS were compared with those of patients with a diagnosis of PD with less than 10 years of duration, and with patients with a diagnosis of others movement disorders not associated with neurodegenerative diseases. Results A total of 75% of patients with ALS had TRODAT results below the levels considered normal; that was also true for 25% of the patients in the control group without neurodegenerative disease, and for 100% of the patients in the PD group. A statistically significant difference was found between patients with ALS and the control group without neurodegenerative disease in the TRODAT values < 0.05. Conclusions Our study fits with the neuropathological and functional evidence that demonstrates the existence of nigrostriatal dysfunction in patients with ALS. Further research to better understand the role of these changes in the pathophysiological process of ALS needs to be performed.

Resumo Antecedentes A coexistência da esclerose lateral amiotrófica (ELA) com formas clínicas da doença de Parkinson (DP), embora incomum, é encontrada em um grau maior do que seria esperado ao acaso. Os mecanismos patológicos da ELA e da DP ainda não são totalmente compreendidos e a coexistência dessas duas doenças sugere que elas podem compartilhar mecanismos em comum. Objetivo Apresentamos uma amostra de pacientes com ELA clinicamente definida ou provável que foram avaliados com tomografia computadorizada por emissão de fóton único (SPECT)/TRODAT e comparados com controles sem ELA. Métodos Pacientes com ELA clinicamente definida ou provável foram avaliados com a escala funcional de esclerose lateral amiotrófica (ALSFRS) para definir a gravidade e foram coletados os seus dados demográficos. Os resultados do TRODAT de pacientes com ELA foram comparados com aqueles de pacientes com diagnóstico de DP com menos de 10 anos de duração e com pacientes com diagnóstico de outros distúrbios do movimento não associados a doenças neurodegenerativas. Resultados Um total de 75% dos pacientes com ELA apresentou resultados de TRODAT abaixo dos níveis considerados normais; 25% no grupo controle sem doença neurodegenerativa e 100% no grupo DP. Uma diferença estatisticamente significativa foi encontrada entre os pacientes com ELA e o grupo controle sem doença neurodegenerativa nos valores de TRODAT p< 0,05. Conclusões Nosso estudo está de acordo com as evidências neuropatológicas e funcionais que demonstram a existência de disfunção nigroestriatal em pacientes com ELA. Mais pesquisas para entender melhor o papel dessas mudanças no processo fisiopatológico da ELA precisam ser realizadas.

Striatal dopamine correlates to memory and attention in Parkinson's disease.

Parkinson's disease (PD) is clinically characterized by motor symptoms, however, specific cognitive impairments are common and poorly understood. This study was designed to assess whether cognitive performances are related to dopamine active transporter (DAT) availability in non-demented PD subjects. Fifty-four non-demented PD patients were enrolled. They underwent [99mTc] TRODAT-1 SPECT/CT and a comprehensive neuropsychological battery including attention/executive and memory tests. Multiple linear regression controlling the effect of age, disease duration and education was applied. The significance level was set at P values of < 0.02. After controlling the effect of age, disease duration and education, lower scores in Rey's Auditory-Verbal Learning Test (RAVLT)/immediate recall were significantly related with lower uptake values in the less affected striatum and more affected caudate. Lower scores in RAVLT/short-term recall were also significantly associated with lower uptake values in the more affected caudate and reduced performance in Trail Making Test part B was related with reduced DAT values in the less affected anterior putamen. Our findings suggest that reduced DAT availability in both caudate and putamen is related to reduced performances in some memory and attention/executive tasks. Nigrocaudate dysfunction is related to lower memory performance while dopamine depletion in the anterior putamen is related to poorer attention performance. If the dopaminergic defects can mostly explain all the cognitive symptoms or this phenomenon just co-occur with other anatomical and biochemical changes remains unknown. Further studies in larger patient samples are required to clarify this issue.

Impairments in gait kinematics and postural control may not correlate with dopamine transporter depletion in individuals with mild to moderate Parkinson's disease.

Parkinson's disease (PD) is a progressive neurodegenerative disorder caused by the loss of dopamine, an important neurotransmitter involved in regulating movement. Nuclear medicine imaging methods such as single-photon emission computed tomography (SPECT) combined with radiotracers can obtain the density of this neurotransmitter. This reduced density leads to classic PD symptoms, such as bradykinesia, tremor and stiffness, consequently affecting walking and postural control. The aim of this study was to verify the correlation between disorders of gait kinematics and postural instability with dopamine depletion in individuals with mild to moderate PD. This is a descriptive, observational cross-sectional study. Subjects were assessed for spatiotemporal gait parameters by a three-dimensional motion capture system, for postural control by stabilometry on a force plate. Dopamine depletion was verified through 99mTc-TRODAT-1 (SPECT-CT) examination. The subjects were in the off-stage of levodopa in all analysis. We evaluated 71 individuals, 32 with mild to moderate PD (HY 2 and 2.5) and 39 healthy individuals matched for gender, age, and height. There was a significant difference between the groups regarding the spatiotemporal variables of gait, as well as in the stabilometric variables. However, there was no correlation between these disturbances and the uptake values of 99mTc-TRODAT-1. The results indicate that there is no correlation between gait impairments and postural instability of individuals with mild to moderate PD and the dopaminergic depletion measured through the 99mTc-TRODAT-1 (SPECT-CT).

Fatores de risco hospitalar para pacientes submetidos à substituição valvar com a bioprótese porcina em instituição universitária / Risk factors for hospital mortality in valve replacement with porcine bioprosthesis at an universitary institution

OBJETIVO: Identificar fatores de risco hospitalar em pacientes submetidos ao implante de bioprótese porcina no Instituto de Cardiologia do Rio Grande do Sul. MÉTODOS: Estudo retrospectivo, com informações de prontuário, de 808 pacientes submetidos ao implante de pelo menos uma bioprótese porcina St. Jude Medical Biocor, no período entre 1994 e 2009. Foi analisada a relação entre mortalidade hospitalar e características clínicas e demográficas definidas em estudos reconhecidos, visando identificar fatores de risco. Foram utilizados testes qui-quadrado, t de Student e regressão logística uni e multivariável (P<0,05). RESULTADOS: Ocorreram 80 (9,9%) óbitos hospitalares. Fatores de risco identificados na regressão logística univariável foram: plastia tricúspide (odds ratio 6,11); lesão mitral (OR 3,98); fração de ejeção de ventrículo esquerdo < 30% (OR 3,82); diabete melito (OR 2,55); fibrilação atrial (OR 2,32); hipertensão pulmonar (OR 2,30); creatinina > 1,4 mg/dL (OR 2,28); cirurgia cardíaca prévia (OR 2,17); hipertensão arterial sistêmica (OR 1,93); classe funcional III e IV (OR 1,92); revascularização miocárdica (OR 1,81); idade > 70 anos (OR 1,80); insuficiência cardíaca congestiva (OR 1,73); e sexo feminino (OR 1,68). Pela regressão logística multivariável, para fatores independentes, identificados: lesão mitral (OR 5,29); plastia tricúspide (OR 3,07); diabete melito (OR 2,72); idade > 70 anos (OR 2,62); revascularização miocárdica (OR 2,43); cirurgia cardíaca prévia (OR 1,82); e hipertensão arterial sistêmica (OR 1,79). CONCLUSÕES: A mortalidade observada nesta casuística é compatível com literatura. Fatores de risco preponderantes são reconhecidos e devem motivar programas específicos de neutralização.

OBJECTIVE: Study designed to identify characteristics of patients related to increased hospital mortality after valve replacement, assumed as risk factors. METHODS: Retrospective study including 808 patients submitted to the implant of St. Jude Biocor porcine bioprosthesis between 1994 and 2009 at Instituto de Cardiologia do Rio Grande do Sul. Primary outcome was hospital death and hospital mortality was related to demographic and surgical characteristics. Statistics include t-test, qui-square test and logistical regression analysis. RESULTS: There were 80 (9.9%) hospital deaths. Risk factors identified with univariable logistical analysis (and respective odds-ratio) were: tricuspid surgery (OR 6.11); mitral valve replacement (OR 3.98); left ventricular ejection fraction < 30% (OR 3.82); diabetes mellitus (OR 2.55); atrial fibrillation (OR 2.32); pulmonary arterial hypertension (OR 2.30); serum creatinine > 1,4 mg/dL (OR 2.28); previous cardiac surgery (OR 2.17); systemic arterial hypertension (OR 1.93); functional class III e IV (OR 1.92); coronary bypass (OR 1.81); age > 70 years-old (OR 1.80); congestive heart failure (OR 1.73); e female gender (OR 1.68). Multivariable logistic regression for independent factors identified preponderant risk factors mitral valve replacement (OR 5,29); tricuspid surgery (OR 3.07); diabetes mellitus (OR 2.72); age > 70 years-old (OR 2.62); coronary bypass (OR 2.43); previous cardiac surgery (OR 1.82); e systemic arterial hypertension (OR 1.79). CONCLUSIONS: Mortality rate is within values found in literature. Identification of risk factors could contribute to changes in surgical indication and medical management in order to reduce hospital mortality.

Risk factors for hospital mortality in valve replacement with porcine bioprosthesis at an universitary institution.

OBJECTIVE: Study designed to identify characteristics of patients related to increased hospital mortality after valve replacement, assumed as risk factors. METHODS: Retrospective study including 808 patients submitted to the implant of St. Jude Biocor porcine bioprosthesis between 1994 and 2009 at Instituto de Cardiologia do Rio Grande do Sul. Primary outcome was hospital death and hospital mortality was related to demographic and surgical characteristics. Statistics include t-test, qui-square test and logistical regression analysis. RESULTS: There were 80 (9.9%) hospital deaths. Risk factors identified with univariable logistical analysis (and respective odds-ratio) were: tricuspid surgery (OR 6.11); mitral valve replacement (OR 3.98); left ventricular ejection fraction < 30% (OR 3.82); diabetes mellitus (OR 2.55); atrial fibrillation (OR 2.32); pulmonary arterial hypertension (OR 2.30); serum creatinine > 1,4 mg/dL (OR 2.28); previous cardiac surgery (OR 2.17); systemic arterial hypertension (OR 1.93); functional class III e IV (OR 1.92); coronary bypass (OR 1.81); age > 70 years-old (OR 1.80); congestive heart failure (OR 1.73); e female gender (OR 1.68). Multivariable logistic regression for independent factors identified preponderant risk factors mitral valve replacement (OR 5,29); tricuspid surgery (OR 3.07); diabetes mellitus (OR 2.72); age > 70 years-old (OR 2.62); coronary bypass (OR 2.43); previous cardiac surgery (OR 1.82); e systemic arterial hypertension (OR 1.79). CONCLUSIONS: Mortality rate is within values found in literature. Identification of risk factors could contribute to changes in surgical indication and medical management in order to reduce hospital mortality.

As diversas faces da síndrome demencial: como diagnosticar clinicamente?: [revisão] / The several faces of dementia syndrome: how to diagnose clinically?: [review]

Objetivos: a presente revisão descreve aspectos clínicos relacionados às diferentes síndromes demenciais, objetivando tornar comum, no meio médico, o conhecimento das nuanças que permeiam o diagnóstico diferencial dessas afecções. Fonte de Dados: foi realizada uma revisão da literatura através das bases de dados Medline, Ovid e Scopus até outubro de 2009, assim como de livros-texto. Artigos com enfoque na fisiopatogenia e na patologia não foram priorizados, tendo em vista os objetivos deste estudo. Síntese dos Dados: este artigo revisa aspectos dealgumas síndromes demenciais reversíveis e irreversíveis, como Doença de Alzheimer e Demência Vascular, enfocando principalmente as características clínicas e diagnósticas que as tornam entidades distintas. Conclusões: a literatura sugere que o processo diagnóstico das síndromes demenciais assenta-se fundamentalmente na clínica, priorizando uma avaliação rigorosa do estado mental. Entretanto, a avaliação por neuroimagem e exames laboratoriais tem participação considerável em determinar a causa subjacente ao quadro demencial, revelando peculiaridades que podem nortear o diagnóstico diferencial. Diagnosticar diferentes etiologias é importante para o prognóstico e conduta terapêutica específica.

Aims: This review describes the clinical aspects related to different dementia syndromes, aiming to become common in the medical , the knowledge of the nuances that permeate the differential diagnosis of these disorders. Data Source: A review of literature published up to October 2009 was conducted on Medline, Ovid, and Scopus databases, as well as on textbooks. Articles that focused on the pathogenesis and pathology were not prioritized, given the objectives of this study. Summary of the Findings: This article reviews some aspects of reversible and irreversible dementia syndromes, such as Alzheimer?s disease and Vascular Disease, focusing on the clinic and diagnostic features that make them distinct entities. Conclusions: The literature suggests that the diagnostic process of dementia syndromes is based mainly on clinical practice, prioritizing a rigorous assessment of mental status. However, neuroimaging evaluation and laboratory tests have considerable input in determining the underlying cause of dementia, revealing peculiarities that can guide the differential diagnosis. The diagnosis of different etiologies is important to the prognosis and the specific therapeutic approach.

Ferro e neurodegeneração / Iron and neurodegeneration

Objetivos: crescente evidências vêm indicando que o ferro tem um papel importante na patogênese dos mecanismos da neurodegeneração. Esta revisão tem por objetivo abordar aspectos de sua absorção, transporte e estoque no corpo humano. Adicionalmente, é abordada a participação do ferro no estresse oxidativo do sistema nervoso central e suas implicações nas doenças neurodegenerativas, com especial destaque para Demência de Alzheimer e Doença de Parkinson. Fonte de dados: foi realizada uma revisão sistemática de de toda a literatura publicada em inglês através das bases de dados Medline, Ovid e Scopus, de janeiro de 2000 setembro de 2007, assim como livros-texto. Foram excluídos os artigos em que os principais enfoques eram de uso de drogas e mutações genéticas relacionadas com metais. Síntese dos dados: este artigo revisa aspectos do metabolismo do ferro como absorção, transporte e estoque; e sua influência no estresse oxidativo e nas principais doenças neurodegenerativas, como Demência de Alzheimer e Doença de Parkinson. Conclusões: a revisão da literatura sugere que estresse oxidativo, associado ao desiquilíbrio na homeostase do ferro, seja uma via importante em relação à patogênese da neurodegeneração. Esse dados requerem novas investigações para esclarecer se este desiquilíbrio é causa ou consequência do processo degenerativo.