Dirnberger G.,Danube University Krems |
Jahanshahi M.,University College London
Journal of Neuropsychology | Year: 2013
Executive dysfunction can be present from the early stages of Parkinson's disease (PD). It is characterized by deficits in internal control of attention, set shifting, planning, inhibitory control, dual task performance, and on a range of decision-making and social cognition tasks. Treatment with dopaminergic medication has variable effects on executive deficits, improving some, leaving some unchanged, and worsening others. In this review, we start by defining the specific nature of executive dysfunction in PD and describe suitable neuropsychological tests. We then discuss how executive deficits relate to pathology in specific territories of the basal ganglia, consider the impact of dopaminergic treatment on executive function (EF) in this context, and review the changes in EFs with disease progression. In later sections, we summarize correlates of executive dysfunction in PD with motor performance (e.g., postural instability, freezing of gait) and a variety of psychiatric (e.g., depression, apathy) and other clinical symptoms, and finally discuss the implications of these for the patients' daily life. © 2013 The British Psychological Society.
Berger T.,Danube University Krems
Energy for Sustainable Development | Year: 2017
Photovoltaic stand-alone systems are largely regarded as a viable option for decentralized rural electrification in developing countries. However, literature review reveals lack of documented experiences with installed PV systems such as Solar home systems as well as general problems with system maintenance and battery up keeping. This paper presents results from monitoring 31 stand-alone PV systems in remote health posts of North Gondar Zone in Ethiopia from installation until system failure; several systematic factors were found to have contributed to failure: lack of clear responsibility for the systems due to regular job rotation among health workers and lack of upfront, gender sensitive training, lack of equipment for maintenance work, very slow and unreliable chain of information in case of system failure and costly double tracking of energy supply. Nonfunctioning PV systems were found to threaten the technology'’s reputation by word of mouth. The results gained in this research provide important lessons for future programs of rural electrification by means of PV systems: they stress the importance of awareness building amongst funding agencies as well as the imperative of intense and sensitive training for users, especially women, and advocate for considering living conditions of users in system design. © 2017 International Energy Initiative
Finsterer J.,Danube University Krems |
Zarrouk Mahjoub S.,Research Unit Human Nutrition and Metabolic Disorders
Expert Opinion on Drug Metabolism and Toxicology | Year: 2012
Introduction: Epilepsy is a frequent CNS manifestation of mitochondrial disorders (MIDs). At present, patients with MID-related epilepsy are largely treated in the same way as any other epilepsy sufferer. The problem with this approach is that some antiepileptic drugs (AEDs) are mitochondrial toxic and care is, therefore, needed when administering these AEDs to patients with MIDs. Areas covered: This review summarizes and discusses the mitochondrial toxicity, tolerability and beneficial effects of AED in patients with MIDs. The literature for this article was retrieved through PubMed using the search terms: 'mitochondrial disorder', 'mitochondriopathy', 'mitochondrial', 'cytopathy', 'metabolic disease', 'epilepsy', 'seizures' and various AEDs alone or in combination. Expert opinion: Mitochondrial-toxic AEDs may trigger or worsen an MID or may be even fatal in single cases. The AED with the most well-known mitochondrial toxicity is valproic acid (VPA), which has been known to exhibit a deleterious effect in patients with POLG1 mutations and patients with myoclonic epilepsy with ragged red fibers syndrome and VPA should only be applied in MIDs in case of a drug-resistant status epilepticus. AEDs other than VPA, which may affect the mitochondrial metabolism, include phenobarbital, carbamazepine, phenytoin, oxcarbazepine, ethosuximide, zonisamide, topiramate, gabapentin and vigabatrin. AEDs which interfere with mitochondrial function should be avoided whenever justifiable to the patient's well-being. Collateral beneficial effects of AEDs should also influence their choice in MIDs.
Teuschl Y.,Danube University Krems |
Brainin M.,Danube University Krems
International Journal of Stroke | Year: 2010
Background: Time is essential for the treatment of acute stroke. Much time is lost outside the hospital, either due to failure in identifying stroke symptoms or due to a delay in notification or transport. We review studies reporting factors associated with better stroke knowledge and shorter time delays. We summarise the evidences for the effect of stroke knowledge and education on people's reaction in the acute situation of stroke. Methods: We searched MEDLINE for studies reporting factors associated with prehospital time of stroke patients, or knowledge of stroke symptoms. Further, we searched for studies reporting educational interventions aimed at increasing stroke symptom knowledge in the population. Findings: We included a total of 182 studies. Surprisingly, those factors associated with better stroke knowledge such as education and sociodemographic variables were not related to shorter time delays. Few studies report shorter time delays or better stroke knowledge in persons having suffered a previous stroke. Factors associated with shorter time delays were more severe stroke and symptoms regarded as serious, but not better knowledge about the most frequent symptoms such as hemiparesis or disorders of speech. Only 25-56% of patients recognised their own symptoms as stroke. While stroke education increases the knowledge of warning signs, a few population studies measured the impact of education on time delays; in such studies, time delays decreased after education. This may partly be mediated by better organisation of EMS and hospitals. Interpretation: There is a discrepancy between theoretical stroke knowledge and the reaction in an acute situation. Help-seeking behaviour is more dependent on the perceived severity of symptoms than on symptom knowledge. Bystanders play an important role in the decision to call for help and should be included in stroke education. Education is effective and should be culturally adapted and presented in a social context. It is unclear which educational concept is best suited to enhance symptom recognition in the acute situation of stroke, especially in view of discrepancies between knowledge and action. © 2010 The Authors. Journal compilation © 2010 World Stroke Organization.
Finsterer J.,Danube University Krems
Heart Failure Reviews | Year: 2010
Left ventricular non-compaction, also known as left ventricular hypertrabeculation (LVHT), is a morphological abnormality of the left ventricular myocardium, characterised by a meshwork of myocardial strings, interlacing, and orderless in arrangement. LVHT is most frequently located in the apex and the lateral wall and may occur with or without other congenital or acquired cardiac abnormalities. LVHT is believed to be congenital in the majority of the cases but may develop during life in single cases (acquired LVHT). Congenital LVHT is believed to result from defective late-stage embryonic development of the myocardial architecture. The pathogenesis of acquired LVHT remains speculative. LVHT is most frequently found on transthoracic echocardiography and cardiac MRI but may be visualised also with other imaging techniques. In the majority of the cases, LVHT is associated with hereditary cardiac, neuromuscular, non-cardiac/non-muscle disease, or chromosomal aberrations. In the majority of the cases, LVHT is complicated by ventricular arrhythmias, systolic dysfunction, cardiac embolism, or sudden cardiac death. LVHT per se does not require a specific treatment. Only in case of complications, such as ventricular arrhythmias, cardioembolism, or systolic dysfunction, adequate therapy is indicated. Though initially assessed as poor, the prognosis of LVHT has meanwhile improved, most likely due to the increased awareness for the abnormality and the timely administration of adequate therapy. © 2010 Springer Science+Business Media, LLC.
Finsterer J.,Danube University Krems
Acta Neurologica Scandinavica | Year: 2012
Among the various central nervous system (CNS) manifestations of mitochondrial disorders (MIDs), cognitive impairment is increasingly recognized and diagnosed (mitochondrial cognitive dysfunction). Aim of the review was to summarize recent findings concerning the aetiology, pathogenesis, diagnosis and treatment of cognitive decline in MIDs. Among syndromic MIDs due to mitochondrial DNA (mtDNA) mutations, cognitive impairment occurs in patients with mitochondrial encephalopathy, lactic acidosis and stroke-like episodes syndrome, myoclonus epilepsy with ragged-red fibres syndrome, mitochondrial chronic progressive external ophthalmoplegia, Kearns-Sayre syndrome, neuropathy, ataxia and retinitis pigmentosa syndrome and maternally inherited diabetes and deafness. Among syndromic MIDs due to nuclear DNA (nDNA) mutations, cognitive decline has been reported in myo-neuro-gastro-intestinal encephalopathy, mitochondrial recessive ataxia syndrome, spinocerebellar ataxia with encephalopathy, Mohr-Tranebjaerg syndrome, leuko-encephalopathy; brain and spinal cord involvement and lactic acidosis, CMT2, Wolfram syndrome, Wolf-Hirschhorn syndrome and Leigh syndrome. In addition to syndromic MIDs, a large number of non-syndromic MIDs due to mtDNA as well as nDNA mutations have been reported, which present with cognitive impairment as the sole or one among several other CNS manifestations of a MID. Delineation of mitochondrial cognitive impairment from other types of cognitive impairment is essential to guide the optimal management of these patients. Treatment of mitochondrial cognitive impairment is largely limited to symptomatic and supportive measures. Cognitive impairment may be a CNS manifestation of syndromic as well as non-syndromic MIDs. Correct diagnosis of mitochondrial cognitive impairment is a prerequisite for the optimal management of these patients. © 2012 John Wiley & Sons A/S.
Finsterer J.,Danube University Krems
European Journal of Neurology | Year: 2011
Central nervous system (CNS) manifestations of mitochondrial disorders (MIDs) are accessible to therapy. Therapy of CNS abnormalities may be categorized as acting on the pathogenic cascade or on the genetic level, which is experimental. Treatment acting on the pathogenic cascade may be classified as non-specific, including antioxidants, electron donors/acceptors, lactate-lowering agents, alternative energy providers, cofactors, avoidance of mitochondrion-toxic drugs, and physiotherapy, or as specific, including drugs against epilepsy, movement disorders, migraine, spasticity, psychiatric abnormalities, hypopituitarism, or bulbar manifestations, ketogenic diet, deep brain stimulation, or artificial ventilation. Stroke-like episodes need to be delineated from ischaemic stroke and require special management. Potentially, mitochondrion-toxic drugs and drug cocktails need to be avoided, seizures should be consequently treated even with mitochondrion-toxic drugs if necessary, and as few drugs as possible should be given. Effective treatment acting on the pathogenic cascade may increase the quality of life and outcome in patients with MID and may prevent a therapeutic nihilism occasionally upcoming with MIDs. © 2010 The Author(s). European Journal of Neurology © 2010 EFNS.
Finsterer J.,Danube University Krems
Movement Disorders | Year: 2011
In the majority of cases, mitochondrial disorders are multisystem conditions that most frequently affect the skeletal muscle, followed by the central nervous system. One of the clinical manifestations of central nervous system involvement is Parkinson's syndrome (PS). Evidence for an association of mitochondrial defects with PS comes from mitochondrial disorder patients who have developed Parkinson's syndrome and from Parkinson's syndrome patients who have developed a mitochondrial disorder. In addition, there are a number of patients with Parkinson's syndrome or Parkinson's disease (PD) who later develop subclinical immunohistological or biochemical indications of mitochondrial defects or accumulates mitochondrial DNA mutations within various cerebral regions. There are also Parkinson's syndrome patients who present with elevated cerebrospinal-fluid lactate by magnetic resonance spectroscopy. Furthermore, it has been shown that mutations in genes causing PD, such as PINK1, parkin, DJ1, alpha-synuclein, and LRRK2, also cause mitochondrial dysfunction, which is one of the reasons why they are called mitochondrial nigropathies. Parkinson's syndrome in patients with a mitochondrial disorder may also result from oxidative stress or exogenous toxins. Treatment of mitochondrial Parkinson's syndrome is not at variance with the treatment of Parkinson's syndrome due to other causes, but because of the multisystem nature of mitochondrial disorders, mitochondrial Parkinson's syndrome requires additional therapeutic support. © 2011 Movement Disorder Society.
Finsterer J.,Danube University Krems
Advances in Experimental Medicine and Biology | Year: 2012
Though inherited mitochondrial disorders (MIDs) are most well known for their syndromic forms, for which widely known acronyms (MELAS, MERRF, NARP, LHON etc.) have been coined, the vast majority of inherited MIDs presents in a non-syndromic form. Since MIDs are most frequently multisystem disorders already at onset or during the disease course, a MID should be suspected if there is a combination of neurological and non-neurological abnormalities. Neurological abnormalities occurring as a part of a MID include stroke-like episodes, epilepsy, migraine-like headache, movement disorders, cerebellar ataxia, visual impairment, encephalopathy, cognitive impairment, dementia, psychosis, hypopituitarism, aneurysms, or peripheral nervous system disease, such as myopathy, neuropathy, or neuronopathy. Non-neurological manifestations concern the ears, the endocrine organs, the heart, the gastrointestinal tract, the kidneys, the bone marrow, and the skin. Whenever there is an unexplained combination of neurological and non-neurological disease in a patient or kindred, a MID should be suspected and appropriate diagnostic measures initiated. Genetic testing should be guided by the phenotype, the biopsy findings, and the biochemical results. © 2012 Springer Science+Business Media B.V.
Edelmann N.,Danube University Krems
Cyberpsychology, Behavior, and Social Networking | Year: 2013
Little research focuses on lurking in the online environment or considers lurking as a valid and important form of online behavior. This may be due to the fact that there are a number of definitions, and most of them focus on a lack of participation or contribution or see it as a problematic behavior that needs to be changed. Such definitions have given lurkers a negative connotation. They need to be considered as an important factor in online research, starting with a clearer and more positive definition of lurking. It is also necessary to understanding why users decide to lurk, what activities lurkers engage in, and whether the online environment is more valuable by turning lurkers into posters. © Copyright 2013, Mary Ann Liebert, Inc. 2013.