Parkinson's Disease: Risk Factor Modification and Prevention.

The global burden of Parkinson's disease (PD) has increased from 2.5 to 6.1 million since the 1990s. This is expected to rise as the world population ages and lives longer. With the current consensus on the existence of a prediagnostic phase of PD, which can be divided into a preclinical stage and a prodromal stage, we can better define the risk markers and prodromal markers of PD in the broader context of PD pathogenesis. Here, we review this pathogenetic process, and discuss the evidence behind various heritability factors, exposure to pesticides and farming, high dairy consumption, and traumatic brain injuries that have been known to raise PD risk. Physical activity, early active lifestyle, high serum uric acid, caffeine consumption, exposure to tobacco, nonsteroidal anti-inflammatory drugs, and calcium channel blockers, as well as the Mediterranean and the MIND diets are observed to lower PD risk. This knowledge, when combined with ways to identify at-risk populations and early prodromal PD patients, can help the clinician make practical recommendations. Most importantly, it helps us set the parameters for epidemiological studies and create the paradigms for clinical trials.

Movement Disorders Emergencies.

Many acute and potentially life-threatening medical conditions have hyperkinetic or hypokinetic movement disorders as their hallmark. Here we review the clinical phenomenology, and diagnostic principles of neuroleptic malignant syndrome, malignant catatonia, serotonin syndrome, Parkinsonism hyperpyrexia, acute parkinsonism, acute chorea-ballism, drug-induced dystonia, and status dystonicus. In the absence of definitive lab tests and imaging, only a high index of clinical suspicion, awareness of at-risk populations, and variations in clinical presentation can help with diagnosis. We also discuss the principles of management and rationale behind treatment modalities in the light of more recent evidence.

GuitarPD: A Randomized Pilot Study on the Impact of Nontraditional Guitar Instruction on Functional Movement and Well-Being in Parkinson's Disease.

Playing musical instruments may have positive effects on motor, emotional, and cognitive deficits in patients with Parkinson's disease (PD). This pilot study examined the feasibility of a six-week nontraditional guitar instruction program for individuals with PD. Twenty-six participants with idiopathic PD (Age: 67.22 ± 8.07; 17 males) were randomly assigned to two groups (intervention first or 6 weeks of usual care control exposure) with stepwise exposure to the guitar intervention condition with cross-over at six weeks. Outcomes were assessed at baseline, 6, 12, and 18 weeks. Twenty-four participants completed the study. Combined analysis of the groups showed significant BDI-II improvement immediately after intervention completion (3.04 points, 95% CI [-5.2, -0.9], p = 0.04). PDQ-39 total quality of life scores improved from baseline to immediately postintervention 5.19 points (95% CI [-9.4, -1.0]) at trend significance (corrected p = 0.07). For Group 1 (exposed to the intervention first), MDS-UPDRS total scores improved by a mean of 8.04 points (95% CI [-12.4, -3.7], p = 0.004) and remained improved at 12 weeks by 10.37 points (95% CI [-14.7, -6.0], p < 0.001). This group also had significant improvements in mood and depression at weeks 6 and 12, remaining significant at week 18 (BDI-II: 3.75, 95% CI [-5.8, -1.7], p = 0.004; NeuroQoL-depression: 10.6, 95% CI [-4.9. -1.4], p = 0.004), and in anxiety at week 6 and week 18 (NeuroQoL; 4.42, 95% CI [-6.8, -2.1], p = 0.004; 3.58, 95% CI [-5.9, -1.2], p = 0.02, respectively). We found clinically and statistically significant improvements in mood/anxiety after 6 weeks of group guitar classes in individuals with PD. Group guitar classes can be a feasible intervention in PD and may improve mood, anxiety, and quality of life.

Functional Activities Detected in the Olfactory Bulb and Associated Olfactory Regions in the Human Brain Using T2-Prepared BOLD Functional MRI at 7T.

Olfaction is a fundamental sense that plays a vital role in daily life in humans, and can be altered in neuropsychiatric and neurodegenerative diseases. Blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) using conventional echo-planar-imaging (EPI) based sequences can be challenging in brain regions important for olfactory processing, such as the olfactory bulb (OB) and orbitofrontal cortex, mainly due to the signal dropout and distortion artifacts caused by large susceptibility effects from the sinonasal cavity and temporal bone. To date, few studies have demonstrated successful fMRI in the OB in humans. T2-prepared (T2prep) BOLD fMRI is an alternative approach developed especially for performing fMRI in regions affected by large susceptibility artifacts. The purpose of this technical study is to evaluate T2prep BOLD fMRI for olfactory functional experiments in humans. Olfactory fMRI scans were performed on 7T in 14 healthy participants. T2prep BOLD showed greater sensitivity than GRE EPI BOLD in the OB, orbitofrontal cortex and the temporal pole. Functional activation was detected using T2prep BOLD in the OB and associated olfactory regions. Habituation effects and a bi-phasic pattern of fMRI signal changes during olfactory stimulation were observed in all regions. Both positively and negatively activated regions were observed during olfactory stimulation. These signal characteristics are generally consistent with literature and showed a good intra-subject reproducibility comparable to previous human BOLD fMRI studies. In conclusion, the methodology demonstrated in this study holds promise for future olfactory fMRI studies in the OB and other brain regions that suffer from large susceptibility artifacts.

Differential Changes in Arteriolar Cerebral Blood Volume between Parkinson's Disease Patients with Normal and Impaired Cognition and Mild Cognitive Impairment (MCI) Patients without Movement Disorder - An Exploratory Study.

Cognitive impairment amongst Parkinson's disease (PD) patients is highly prevalent and associated with an increased risk of dementia. There is growing evidence that altered cerebrovascular functions contribute to cognitive impairment. Few studies have compared cerebrovascular changes in PD patients with normal and impaired cognition and those with mild-cognitive-impairment (MCI) without movement disorder. Here, we investigated arteriolar-cerebral-blood-volume (CBVa), an index reflecting the homeostasis of the most actively regulated segment in the microvasculature, using advanced MRI in various brain regions in PD and MCI patients and matched controls. Our goal is to find brain regions with altered CBVa that are specific to PD with normal and impaired cognition, and MCI-without-movement-disorder, respectively. In PD patients with normal cognition (n=10), CBVa was significantly decreased in the substantia nigra, caudate and putamen when compared to controls. In PD patients with impaired cognition (n=6), CBVa showed a decreasing trend in the substantia nigra, caudate and putamen, but was significantly increased in the presupplementary motor area and intracalcarine gyrus compared to controls. In MCI-patients-without-movement-disorder (n=18), CBVa was significantly increased in the caudate, putamen, hippocampus and lingual gyrus compared to controls. These findings provide important information for efforts towards developing biomarkers for the evaluation of potential risk of PD dementia (PDD) in PD patients. The current study is limited in sample size and therefore is exploratory in nature. The data from this pilot study will serve as the basis for power analysis for subsequent studies to further investigate and validate the current findings.

The Hitchhiker's guide to the rhinencephalon.

Pathology of the rhinencephalon has been a subject of interest in the fields of neurodegenerative diseases, trauma, epilepsy and other neurological conditions. Most of what is known about the human rhinencephalon comes from comparative anatomy studies in other mammals and histological studies in primates. Functional imaging studies can provide new and important insight into the function of the rhinencephalon in humans but have limited spatial resolution, limiting its contribution to the study of the anatomy of the human rhinencephalon. In this study we aim to provide a brief and objective review of the anatomy of this important and often overlooked area of the nervous system.

Availability of olfactory bulb: experience from a British Brain Bank.

The olfactory bulb and tract (OB/OT) are among the earliest structures in the brain to undergo pathological changes in many neurodegenerative conditions. The availability of OB/OT samples from brain specimens in brain banks therefore assumes importance. We collected data from 5 years (2006-2010) regarding the presence or absence of OB/OT material in cases received by the Queen Square Brain Bank (QSBB) for Neurological Disorders, UCL Institute of Neurology, UK, to estimate availability of OB/OT material at the brain bank and also to look for possible associations. Of the 438 cases received, 320 had complete data regarding OB/OT and 29.4% of these had OB/OT in at least one half of the specimen. Unavailability of OB/OT was associated with larger post-mortem delays (p<0.001), suggesting that the delay might render the tissue more friable and hence lead to its loss. Brains from female donors also tended to have a higher availability in our samples.

The Hitchhiker’s guide to the rhinencephalon / Um guia prático sobre a anatomia do rinencéfalo

ABSTRACT Pathology of the rhinencephalon has been a subject of interest in the fields of neurodegenerative diseases, trauma, epilepsy and other neurological conditions. Most of what is known about the human rhinencephalon comes from comparative anatomy studies in other mammals and histological studies in primates. Functional imaging studies can provide new and important insight into the function of the rhinencephalon in humans but have limited spatial resolution, limiting its contribution to the study of the anatomy of the human rhinencephalon. In this study we aim to provide a brief and objective review of the anatomy of this important and often overlooked area of the nervous system.

RESUMO As patologias do rinencéfalo tem sido assunto de interesse para os estudiosos das doenças neurodegenerativas, do traumatismo cranio-encefálico, epilepsia e outras doenças neurológicas. A maior parte do conhecimento sobre a anatomia do rinencéfalo vem de estudos de anatomia comparativa com outros mamíferos e estudos histológicos em primatas. Estudos de imagem funcional, apesar de proporcionarem informações úteis e interessantes a respeito do funcionamento do rinencéfalo em humanos, sofrem de resolução espacial limitada, e portanto contribuem de maneira restrita ao estudo dos limites das áreas anatômicas. Neste artigo buscamos proporcionar ao neurologista e neurocientista interessado uma revisão prática e objetiva da anatomia desta área importante e muitas vezes esquecida do sistema nervoso.

Availability of olfactory bulb: experience from a British Brain Bank / Disponibilidade de bulbos olfatórios em um banco de cérebro britânico: a experiência do Queen Square Brain Bank

The olfactory bulb and tract (OB/OT) are among the earliest structures in the brain to undergo pathological changes in many neurodegenerative conditions. The availability of OB/OT samples from brain specimens in brain banks therefore assumes importance. We collected data from 5 years (2006-2010) regarding the presence or absence of OB/OT material in cases received by the Queen Square Brain Bank (QSBB) for Neurological Disorders, UCL Institute of Neurology, UK, to estimate availability of OB/OT material at the brain bank and also to look for possible associations. Of the 438 cases received, 320 had complete data regarding OB/OT and 29.4% of these had OB/OT in at least one half of the specimen. Unavailability of OB/OT was associated with larger post-mortem delays (p<0.001), suggesting that the delay might render the tissue more friable and hence lead to its loss. Brains from female donors also tended to have a higher availability in our samples.

O bulbo e o trato olfatórios (OB/OT) são algumas das estruturas cerebrais mais sensíveis a neurodegeneração. A disponibilidade deste material para estudos neuropatológicos em bancos de cérebro tem, portanto, grande relevância. Coletamos dados referentes a 5 anos (2006-2010) a respeito da presença ou ausência de OB/OT no Queen Square Brain Bank (QSBB) for Neurological Disorders, parte do UCL Institute of Neurology, Reino Unido, para estimar a disponibildade deste material em um banco de cérebro, e também para estudar fatores que influenciam essa disponibilidade. Dos 438 casos recebidos, encontramos dados referentes a presença ou ausência de OB/OT em 320, dos quais 29,4% possuiam OB/OT em pelo menos um lado. A indisponibilidade de OB/OT foi associada a maior intervalo entre a morte e a autópsia(p<0.001), sugerindo que o atraso pode deixar o material mais friável, levando aperda durante a coleta. Cérebros de doadoras femininas apresentaram maior disponibilidade de OB/OT em nossa amostra.