Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085632 (apathy)
 4,089 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Myotonic dystrophy (DM) is an autosomal dominant multisystem disorder involving muscle, brain, heart, eyes and endocrine organs, among others. The molecular basis is an unstable trinucleotide repeat at the 3'-untranslated end of the myotonin protein kinase gene on chromosome 19 q 13.3, and the number of repeats correlates with the severity of muscle weakness. We performed a clinical, psychometric and MRI study on 43 patients with DM and correlated findings with the molecular analysis. Nineteen patients had mild distal muscle weakness, 17 moderate und 7 severe weakness. Thirteen had marked cognitive deficits with reduced speed of cognition, low IQ, and apathy. MRI showed pathological muscle signal in 35 cases with a characteristic mosaic involving distal muscle groups, often sparing the posterior tibial muscle. Cerebral MRI showed significant subcortical white matter lesions in 20 cases and brain atrophy in 15 cases. Clinical and MRI findings of CNS and muscle both correlated with CTG repeat length, but did not parallel each other. DM is a significant disease of the brain as well as muscle, and several aspects of the disease correlate with molecular findings, with a threshold effect for repeats exceeding 1000 trinucleotides. The individual predominance of specific organ involvement probably depends on variable somatic mosaicism of the molecular defect.
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PMID:[Myotonic dystrophy: magnetic resonance tomography and clinico-genetic correlations]. 763 29

Assessment of molecular defects that underlie cognitive deficits observed in mendelian disorders provides a unique opportunity to identify key regulators of human cognition. Congenital Myotonic Dystrophy 1 (cDM1), a multi-system disorder is characterized by both cognitive deficits and a spectrum of behavioral abnormalities, which include visuo-spatial memory deficits, anxiety and apathy. Decreased levels of DMPK (Dystrophia Myotonica-protein kinase), SIX5, a transcription factor or MBNL1 (Muscleblind-like 1), an RNA splice regulator have been demonstrated to contribute to distinct features of cDM1. Mouse strains in which either Dmpk, Six5 or Mbnl1 are inactivated were therefore studied to determine the relative contribution of each gene to these cognitive functions. The open field and elevated plus maze tasks were used to examine anxiety, sucrose consumption was used to assess motivation, whereas the water maze and context fear conditioning were used to examine spatial learning and memory. Cognitive and behavioral abnormalities were observed only in Mbnl1 deficient mice, which demonstrate behavior consistent with motivational deficits in the Morris water maze, a complex visuo-spatial task and in the sucrose consumption test for anhedonia. All three models of cDM1 exhibit normal spatial learning and memory. These data identify MBNL1 as a potential regulator of emotional state with decreased MBNL1 levels underlying the motivational deficits observed in cDM1.
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PMID:Muscleblind1, but not Dmpk or Six5, contributes to a complex phenotype of muscular and motivational deficits in mouse models of myotonic dystrophy. 2036 Aug 42

Myotonic dystrophy type 1 (DM1) represents the 1 chronic neuromuscular disease with the most prominent sleep disorders, including excessive daytime sleepiness (EDS), sleep apneas, periodic leg movements during sleep, and rapid eye movement sleep dysregulation. The large majority of DM1 patients complain about EDS, which may have a deleterious impact on work, domestic responsibilities, social life, and quality of life. Here, we review the extant literature and report that studies are largely supportive of the view that DM1-related EDS is primarily caused by a central dysfunction of sleep regulation rather than by sleep-related disordered breathing (SRDB) or sleep fragmentation. The pathogenesis of EDS in DM1 still remains unclear but several arguments favor a model in which brain/brainstem nuclear accumulations of toxic expanded DM protein kinase (DMPK) gene are responsible for aberrant genes expression in modifying alternative splicing. Regarding management, early recognition, and treatment of SRDB with nocturnal noninvasive mechanical ventilation is first mandatory. However, despite its appropriate management, EDS often persists and may require a psychostimulant but no consensus has been yet established. Further studies are needed to clarify the discrepancies between daytime sleepiness/fatigue complaints and subjective/objective measurement of daytime sleepiness, the role of cognitive impairment and apathy in this relationship, and its reversibility with appropriate management.
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PMID:Daytime sleepiness and myotonic dystrophy. 2343 Jun 86