Author Interviews, Imperial College, Parkinson's / 23.09.2015

Dr. Ilse S. Pienaar Honorary Lecturer in Neuroscience at Imperial College London (& Snr. Lecturer in Cellular Pathology, Northumbria University) Centre for Neuroinflammation & Neurodegeneration Division of Brain Sciences Faculty of Medicine Imperial College London Hammersmith Hospital Campus London United KingdomMedicalResearch.com Interview with: Dr. Ilse S. Pienaar Honorary Lecturer in Neuroscience at Imperial College London (& Snr. Lecturer in Cellular Pathology, Northumbria University) Centre for Neuroinflammation & Neurodegeneration Division of Brain Sciences Faculty of Medicine Imperial College London Hammersmith Hospital Campus London United Kingdom   Medical Research: What is the background for this study? What are the main findings? Dr. Pienaar: A highly heterogeneous brainstem structure, the pedunculopontine nucleus (PPN) has been deemed a promising target for the delivery of deep-brain stimulation (DBS), to alleviate aspects of Parkinson's disease (PD), especially gait and postural instability. However, optimal therapeutic targeting of the PPN has been hampered due to DBS being unable to discriminate between cell types being targeted. We optomised a novel technique, Designer Receptors Exclusively Activated by Designer Drugs (DREADD) in a rat model of PD, by which to target only the PPN cholinergic neurons. A series of behavioral tests revealed that selective stimulation of the PPN cholinergics completely reverses gait problems and postural instability in the PD rats. (more…)
Author Interviews, JAMA, McGill, Parkinson's / 15.06.2015

Ron Postuma, MD, MSc Associate Professor Department of Neurology Montreal General Hospital Montreal, QuebecMedicalResearch.com Interview with: Ron Postuma, MD, MSc Associate Professor Department of Neurology Montreal General Hospital Montreal, Quebec Medical Research: What is the background for this study? What are the main findings? Dr. Postuma: The background is that we often think about Parkinson’s Disease as a single disease.  However, every clinician knows that there is a great deal of variability from patient to patient.  If we can understand the main aspects that separate patients into groups, we can target therapy better. The analysis used a semi-automated means to divide Parkinson’s patients into groups, using extensive information about motor and non-motor aspects of disease.  We found that the non-motor symptoms, especially cognition, sleep disorders, and blood pressure changes were the most powerful predictors of which group a patient would be in.  Based on these non-motor (and some motor aspects), the most accurate way to divide patients was into three groups - diffuse (many non-motor symptoms), pure motor, and intermediate (halfway between the other).  We then followed patients over time.  The diffuse group had, by far, the worse prognosis.  This was not only for the non-motor aspects, but the motor as well. (more…)
Author Interviews, Exercise - Fitness, Parkinson's / 03.06.2015

Dr. Lori P. Altmann Department of Speech, Language, and Hearing Sciences Center for Movement Disorders and Neurorestoration University of Florida, Gainesville, FloridaMedicalResearch.com Interview with: Dr. Lori P. Altmann Department of Speech, Language, and Hearing Sciences Center for Movement Disorders and Neurorestoration University of Florida, Gainesville, Florida Medical Research: What is the background for this study? What are the main findings? Dr. Altmann: There are a multitude of studies from our labs and others examining the effects of doing a variety of different cognitive tasks while walking or while maintaining postural control, and the results across studies are consistent—motor performance usually declines.  These “dual task effects” are exaggerated in healthy older adults, and are even more pronounced in people with Parkinson disease (PD).  Our study investigated dual task effects during cycling in healthy older adults and people with Parkinson disease.  In contrast to most studies of this type which typically contrast dual task effects of two cognitive tasks, we used an array of 12 cognitive tasks of graded difficulty, from very very easy to extremely difficult.  One of our primary goals was to establish that the dual task effects were directly related to the difficulty of the cognitive task. Our primary findings were that, instead of cycling slower when doing various cognitive task, both groups of participants sped up, and the amount they sped up was directly related to the difficulty of cognitive tasks.  In the easiest task, cycling speed increased by an average of about 25%, With some participants actually doubling their single task speed. There was no evidence that this increase in cycling speed came as a result of prioritizing cycling over the cognitive tasks, as scores on the cognitive tasks either remained the same or got slightly better.  Interestingly, people with Parkinson disease still showed faster cycling during the easiest tasks, but did not benefit as much from the dual task as the healthy adults. We attribute our findings to arousal that is triggered by both the cycling and the cognitive tasks which increases attentional resources that can be used for both motor and cognitive processing.  We believe the findings haven’t been documented before because most studies use gait or balance as the motor tasks, and these are much more difficult tasks that demand more attentional resources, leading to the typical findings of dual task costs instead of dual task benefits. The decrease in dual task benefits experienced by people with Parkinson disease, we believe, is due to the effects of Parkinson disease on neurotransmitters.  Both cognitive and physiological arousal increase the production of dopamine and norepinephrine in the brain, and disease processes in Parkinson disease interfere with production of these neurotransmitters, thus limiting arousal-based increases in attentional resources. (more…)
Author Interviews, Brain Injury, Neurology, Parkinson's / 20.02.2015

MedicalResearch.com Interview with: Line Kenborg, MSc, PhD Survivorship Unit Danish Cancer Society Research Center Copenhagen Medical Research: What is the background for this study? What are the main findings? Response: The hypothesis that head injuries increase the risk for Parkinson disease has been examined in many studies during the past decades, but the findings have been highly inconsistent. We have previously examined the hypothesis in a study based on information on head injuries and Parkinson disease from the Danish National Hospital Registry. In this study, we found a positive association between a hospital contact for a head injury in middle or late adulthood and a diagnosis of Parkinson disease. The reported association, however, was almost entirely due to injuries that occurred during the months preceding the first hospital contact for Parkinson disease. Because we used information from registries, we lacked detailed diagnostic information to distinguish Parkinson disease from other types of parkinsonism, and we had no information on milder head injuries and head injuries in early life. So we wanted to study whether head injuries throughout life increased the risk for Parkinson disease in the largest interview-based case-control study to date including patients with a verified diagnosis of Parkinson disease. The main finding of our study is that we do not find any association between head injuries and Parkinson disease. (more…)
Author Interviews, Parkinson's / 14.12.2014

Filip Scheperjans MD Department of Neurology Helsinki University Central Hospital Department of Neurological Sciences University of Helsinki, Helsinki, FinlandMedicalResearch.com Interview with: Filip Scheperjans MD Department of Neurology Helsinki University Central Hospital Department of Neurological Sciences University of Helsinki, Helsinki, Finland Medical Research: What is the background for this study? What are the main findings? Dr. Scheperjans: In Parkinson’s disease (PD), the first neurodegenerative changes are seen in the olfactory bulb and enteric nervous system. Correspondingly, most Parkinson’s disease patients suffer from hyposmia and gastrointestinal symptoms, frequently years before motor symptoms evolve. Therefore, it has been suggested that an environmental factor acting through the nose or gut, could be involved in Parkinson’s disease. Interestingly, those two habitats are where our body gets mostly exposed to environmental agents, including microbes. Previous attempts to identify microbes related to Parkinson’s disease pointed to Helicobacter pylori and small intestinal bacterial overgrowth, but in the end had been somewhat inconclusive. But there possibly was a signal. We saw next generation sequencing approaches as a new opportunity to revisit the microbe theory in PD. Studies of gut microbiome composition in neurodegenerative disease have not been published before, although alterations in gut microbiota have been demonstrated in many other diseases and gut microbiota are in close interaction with the central nervous system. The fecal microbiome of Parkinson’s disease subjects clearly differed from that of matched controls and this difference was independent of the potential confounders that we assessed. The most significant finding was that the abundance of bacteria from the Prevotellaceae family was reduced by 78% in Parkinson’s disease patients. A low abundance of Prevotellaceae was 86% sensitive for PD, but rather unspecific. However, a combination of 4 bacterial families increased specificity for PD to 90%. So microbiome analysis performed quite well in distinguishing Parkinson’s disease patients from control subjects. Another interesting finding was that, within the Parkinson’s disease group, abundance of Enterobacteriaceae bacteria was related to the motor symptoms of patients. They were positively associated with the severity of postural instability and gait difficulty. (more…)
Author Interviews, Neurology, Parkinson's / 30.07.2014

Associate Professor of Psychiatry and Neurology Perelman School of Medicine at the University of Pennsylvania Philadelphia, PA 19104-2676 Parkinson's Disease Research, Education and Clinical Center (PADRECC) Mental Illness Research, Education and Clinical Center (MIRECC) Philadelphia Veterans Affairs Medical CenterMedicalResearch.com Interview with: Daniel Weintraub, M.D. Associate Professor of Psychiatry and Neurology Perelman School of Medicine at the University of Pennsylvania Philadelphia, PA 19104-2676 Parkinson's Disease Research, Education and Clinical Center (PADRECC) Mental Illness Research, Education and Clinical Center (MIRECC) Philadelphia Veterans Affairs Medical Center Medical Research: What are the main findings of the study? Dr. Weintraub: That there is mixed evidence for the efficacy of naltrexone in the treatment of impulse control disorders in Parkinson’s disease, and the evidence is sufficient to support further study of this compound class for this indication.  In addition, the study demonstrates that it is possible to conduct a clinical trial in this area. (more…)
Author Interviews, Lancet, Parkinson's / 11.06.2014

Richard Gray Professor of Medical Statistics Clinical Trial Service Unit Richard Doll Building, OxfordMedicalResearch Interview with: Richard Gray Professor of Medical Statistics Clinical Trial Service Unit Richard Doll Building, Oxford MedicalResearch: What are the main findings of the study? Prof. Gray: We found that, when we asked patients with Parkinson’s disease how their drugs affected their overall quality of life, the older drug levodopa was better than newer, more expensive drugs and that this benefit persisted for at least seven years from starting treatment. (more…)
Author Interviews, Parkinson's / 21.12.2013

Priv. Doz. Dr. Carsten Buhmann Department of Neurology University Medical Center Hamburg-Eppendorf, Hamburg, Germany.MedicalResearch.com Interview with: Priv. Doz. Dr. Carsten Buhmann Department of Neurology University Medical Center Hamburg-Eppendorf Hamburg, Germany. MedicalResearch.com: What are the main findings of the study? Answer: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) has no negative but rather a beneficial effect on driving in patients with Parkinsons´s disease (PD). Driving not only was superior in even more clinically affected PD patients with DBS compared with PD patients without DBS but also patients with DBS drove better with stimulation than with levodopa. This might reflect favorable driving-relevant nonmotor effects due to STN-DBS. (more…)
Author Interviews, Cognitive Issues, Mayo Clinic, Parkinson's, PLoS / 19.09.2013

Michelle M. Mielke, Ph.D. Associate Professor Department of Health Sciences Research Division of Epidemiology Mayo Clinic 200 First Street SW Rochester, MN 55905MedicalResearch.com: Interview with: Michelle M. Mielke, Ph.D. Associate Professor Department of Health Sciences Research Division of Epidemiology Mayo Clinic 200 First Street SW Rochester, MN 55905 MedicalResearch.com: What are the main findings of the study? Dr. Mielke: Among Parkinson’s disease (PD) patients, plasma levels of ceramides and monohexylceramides were higher in patients with cognitive impairment or dementia compared to patients who were cognitively normal.  Levels of these lipids were also higher in the combined group of PD patients compared to non-PD controls but the number of controls were small. (more…)
Alzheimer's - Dementia, Author Interviews, CMAJ, JAMA, Mayo Clinic, Parkinson's / 18.09.2013

Rodolfo Savica, MD, MSc Department of Neurology, College of Medicine Division of Epidemiology, Department of Health Sciences Research, College of Medicine, Mayo Clinic, Rochester, MinnesotaMedicalResearch.com Interview with: Rodolfo Savica, MD, MSc Department of Neurology, College of Medicine Division of Epidemiology, Department of Health Sciences Research, College of Medicine, Mayo Clinic, Rochester, Minnesota   MedicalResearch.com: What are the main findings of this study? Dr. Savica: This study is the first in North America to explore the incidence of DLB and PDD in a population based sample. We found that the overall incidence of dementia with Lewy bodies (DLB), considered the second leading cause of neurodegenerative dementia after Alzheimer`s disease, is lower than that of Parkinson`s disease (PD), increases steeply with age, and is markedly higher in men than in women. (more…)
Author Interviews, Biomarkers, Parkinson's, University of Pennsylvania / 13.08.2013

Alice Chen-Plotkin, MD Assistant Professor Department of Neurology University of Pennsylvania School of Medicine MedicalResearch.com: Interview with Alice Chen-Plotkin, MD Assistant Professor Department of Neurology University of Pennsylvania School of Medicine   MedicalResearch.com: What are the main findings of the study? Answer: Parkinson's disease (PD) is an incurable neurodegenerative disease.  Many neurons die, but the neurons that make dopamine (dopaminergic neurons) are particularly vulnerable.  We think that the disease actually starts well before the time when people show clinical symptoms.  We were therefore interested in finding proteins from the blood that correlated with better or worse dopaminergic neuron integrity.  Since it's hard to access the dopaminergic neurons directly, we looked at a tracer that labels the ends of the dopaminergic neurons in people who do not have Parkinson's disease but are at high risk for developing it, and we also looked at the age at onset of PD in people who are already symptomatic.  Screening just under 100 different proteins from the blood, we found that higher plasma levels of apolipoprotein A1 (ApoA1) were correlated with better tracer uptake in the people who did not yet have PD, and with older ages at onset in the people who already had PD.  These data suggest that plasma ApoA1 may be a marker for PD risk, with higher levels being relatively protective. (more…)
Author Interviews, Hormone Therapy, Neurological Disorders, Parkinson's / 28.07.2013

 Kalipada Pahan, Ph.D.  The Floyd A. Davis, M.D., Endowed Chair of Neurology Professor Departments of Neurological Sciences, Biochemistry and Pharmacology Rush University Medical Center 1735 West Harrison St, Suite 320 Chicago, IL 60612MedicalResearch.com Interview with: Kalipada Pahan, Ph.D. The Floyd A. Davis, M.D., Endowed Chair of Neurology Professor Departments of Neurological Sciences, Biochemistry and Pharmacology Rush University Medical Center 1735 West Harrison St, Suite 320 Chicago, IL 60612 MedicalResearch.com: What are the main findings of the study? Dr. Pahan: While different toxins and a number of complex genetic approaches are used to model Parkinson’s disease in mice, this study delineates that simple castration is sufficient to cause persistent Parkinson’s like pathology and symptoms in male mice. This simple, but persistent, model may be helpful in discovering drugs against Parkinson’s disease. Furthermore, these results suggest that sudden drop of testosterone level could trigger Parkinson’s disease. (more…)
Author Interviews, Neurological Disorders, Parkinson's / 29.05.2013

MedicalResearch.com eInterview with Dr. Emanuele Cereda Nutrition and Dietetics Service, Fondazione IRCCS Policlinico San Matteo Viale Golgi 19, 27100 Pavia, Italy MedicalResearch.com: What are the main findings of the study? Dr. Cereda: A large analysis of more than 100 studies shows that exposure to pesticides, or bug and weed killers, and solvents is likely associated with a higher risk of developing Parkinson’s disease. MedicalResearch.com: Were any of the findings unexpected? Dr. Cereda: In first instance I can say no as in every day clinical practice we frequently see patients reporting such exposure. Accordingly, it appears quite obvious to look at these exposures as risk factors. Unfortunately, from an epidemiologic point of view this is not enough! That's why we did this study. Amazing rather than surprising was the fact that commonly the sources of funding in the studies we retrieved and included in meta-analysis were health or health-related institutions, private foundations (mainly Parkinosn’s disease foundations), or government or para-government companies. No study acknowledged the involvement of any chemicals manufacturer! (more…)