Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0917816 (mental retardation)
 15,867 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of the present study was to verify the clinical efficacy of melatonin (MLT) in children, adolescents and young adults with wake-sleep disorder and mental retardation, most of them on chronic anticonvulsant therapy for epileptic seizures, by means of a randomized, double-blind, placebo-controlled cross-over trial. Twenty-five patients (16 males, nine females), aged from 3.6 to 26 years (mean 10.5 years), all affected with mental retardation mostly with epileptic seizures, were randomized to oral synthetic fast-release MLT or placebo. Melatonin was initiated at the daily dose of 3 mg, at nocturnal bedtime. In case of inefficacy, MLT dose could be titrated up to 9 mg the following 2 weeks at increments of 3 mg/week, unless the patient was unable to tolerate it. The analysis of all the sleep logs disclosed a significant treatment effect of melatonin on sleep latency (P = 0.019). Melatonin was well tolerated in all patients and no side effects were reported. In conclusion, our study supports the efficacy of MLT in young patients with mental disabilities and epileptic seizures in improving the wake-sleep disorders such as time to fall asleep. Overall, MLT appeared to influence the seizure frequency poorly, though there may be occasional seizure worsening or improving. Such a dual effect requires further studies in young epileptic patients.
 ...
PMID:Melatonin in wake-sleep disorders in children, adolescents and young adults with mental retardation with or without epilepsy: a double-blind, cross-over, placebo-controlled trial. 1527 98

Autism is a developmental disability characterized by severe deficits in social interaction and communication, and the presence of repetitive-ritualistic behaviors. Sleep problems are frequently reported by parents of children with autism with prevalence estimates of 44-83% for sleep disorders in this population. To better understand sleep in autism, we surveyed sleep problems in 210 children with autism using a Likert-based questionnaire for parent report. The most frequently reported sleep problems included difficulty in falling asleep, restless sleep, not falling asleep in own bed, and frequent wakenings. Least frequently reported sleep problems were sleep walking, morning headaches, crying during sleep, apnea, and nightmares. When surveys were divided into mental retardation (MR)/not MR categories, no significant differences were identified in frequencies of reported sleep problems except for waking at night which occurred much more frequently in the MR group. There was also no difference in sleep problems related to age of the child other than nocturnal enuresis. An association was noted between certain medical problems and sleep problems. Vision problems, upper respiratory problems, and runny nose were associated with decreased nighttime sleep. Vision problems, poor appetite, and poor growth were associated with increased nighttime waking. Poor appetite and poor growth were associated with decreased willingness to fall asleep. This study confirms a high prevalence of sleep problems reported by parents of children with autism and points to the need for more systematic research as an initial step in developing treatment strategies.
 ...
PMID:Sleep problems in children with autism. 1533 62

Developmental disorders such as mental retardation, language disorders, autistic disorders, learning disorders, attention deficit/hyperactivity syndrome and conduct disorders are an important part of our daily practice in child neurology. Early diagnosis and early or timely intervention in these kinds of developmental disorders were stressed and family support in child-rearing was emphasized in this symposium. In addition to the above, sleep disorders in developmental disorders were discussed.
 ...
PMID:[Early diagnosis and early intervention in children with developmental disorders: introductory remarks]. 1577 24

The Smith-Magenis syndrome is a rare, complex multisystemic disorder featuring, mental retardation and multiple congenital anomalies caused by a heterozygous interstitial deletion of chromosome 17p11.2. The phenotype of Smith-Magenis syndrome is characterized by a distinct pattern of features including infantile hypotonia, generalized complacency and lethargy in infancy, minor skeletal (brachycephaly, brachydactyly) and craniofacial features, ocular abnormalities, middle ear and laryngeal abnormalities including hoarse voice, as well as marked early expressive speech and language delays, psychomotor and growth retardation, and a 24-hour sleep disturbance. A striking neurobehavioral pattern of stereotypies, hyperactivity, polyembolokoilamania, onychotillomania, maladaptive and self-injurious and aggressive behavior is observed with increasing age. The diagnosis of Smith-Magenis syndrome is based upon the clinical recognition of a constellation of physical, developmental, and behavioral features in combination with a sleep disorder characterized by inverted circadian rhythm of melatonin secretion. Many of the features of Smith-Magenis syndrome are subtle in infancy and early childhood, and become more recognizable with advancing age. Infants are described as looking "cherubic" with a Down syndrome-like appearance, whereas with age the facial appearance is that of relative prognathism. Early diagnosis requires awareness of the often subtle clinical and neurobehavioral phenotype of the infant period. Speech delay with or without hearing loss is common. Most children are diagnosed in mid-childhood when the features of the disorder are most recognizable and striking. While improvements in cytogenetic analysis help to bring cases to clinical recognition at an earlier age, this review seeks to increase clinical awareness about Smith-Magenis syndrome by presenting the salient features observed at different ages including descriptions of the neurologic and behavioral features. Detailed review of the circadian rhythm disturbance unique to Smith-Magenis syndrome is presented. Suggestions for management of the behavioral and sleep difficulties are discussed in the context of the authors' personal experience in the setting of an ongoing Smith-Magenis syndrome natural history study.
 ...
PMID:Neurologic and developmental features of the Smith-Magenis syndrome (del 17p11.2). 1664 92

Smith-Magenis syndrome (SMS) is a mental retardation syndrome with distinctive behavioral characteristics, dysmorphic features and congenital anomalies ascribed to an interstitial deletion of chromosome 17p11.2. Severe sleep disturbances and maladaptative daytime behavior have been linked to an abnormal circadian secretion pattern of melatonin, with a diurnal instead of nocturnal secretion of this hormone. SMS provides a demonstration of a biological basis for sleep disorder in a genetic disease. Considering that clock genes mediate the generation of the circadian rhythm, haploinsufficiency for a circadian system gene, mapping to chromosome 17p11.2 might cause the inversion of the melatonin circadian rhythm in SMS. The disorder of circadian timing in SMS might also affect the entrainment pathway (retinohypothalamic tract), pacemaker functions (suprachiasmatic nucleus) or synthesis and release of melatonin by the pineal gland. Elucidating pathophysiological mechanisms of behavioral phenotypes in genetic disease can provide an original therapeutic approach in SMS: blockade of endogenous melatonin production during the day combined with exogenous melatonin administration in the evening.
 ...
PMID:Inverted rhythm of melatonin secretion in Smith-Magenis syndrome: from symptoms to treatment. 1689 Apr 50

GABA(A) receptors are the major inhibitory neurotransmitter receptors in the mammalian brain, implicated in anxiety, depression, epilepsy, insomnia, and learning and memory. Here, we present several lines of evidence for involvement of the GABAergic system, and in particular the GABA(A) receptor-mediated function, in fragile X syndrome, the most common form of inherited mental retardation. We argue that an altered expression of the GABA(A) receptor has neurophysiologic and functional consequences that might relate to the behavioural and neurological phenotype associated with fragile X syndrome. Interestingly, some neuropsychiatric disorders, such as anxiety, epilepsy and sleep disorders, are effectively treated with therapeutic agents that act on the GABA(A) receptor. Therefore, the GABA(A) receptor might be a novel therapeutic target for fragile X syndrome.
 ...
PMID:The GABAA receptor: a novel target for treatment of fragile X? 1759 Apr 48

Mulvihill-Smith syndrome (MSS) is characterized by premature aging, multiple pigmented nevi, decreased facial subcutaneous fat, microcephaly, short stature, mental retardation and recurrent infections, however the adult phenotype of MSS has yet to be delineated. We report a 28-year-old woman with Mulvihill-Smith syndrome, who had a solid pseudopapillary cystic tumor of her pancreas at age 17 years. Her distinctive sleep pattern includes severe insomnia with disappearance of sleep spindles and K-complexes, persisting muscle tone, and loss of slow wave sleep. The clinical and neurophysiological studies are compatible with agrypnia excitata, a sleep disorder attributable to a dysfunction of the thalamo-limbic system. Brain magnetic resonance imaging and single photon emission computed tomography revealed structural and functional deficits in the dorsomedial region of the thalamus and indicated that an alteration in the thalamo-limbic system may underlie the sleep disturbances in MSS. Furthermore, the rapid and severe decline in acquired cognitive function showed the distinct cognitive impairments resembling dementia, including intellectual deficits, memory disorder and executive dysfunction. We posit that an early onset tumor, sleep disorder and cognitive decline are adult manifestations of Mulvihill-Smith syndrome.
 ...
PMID:Case report: Adult phenotype of Mulvihill-Smith syndrome. 1921 35

Pyridoxal phosphate and pyridoxamine phosphate, the catalytically active forms of vitamin B(6), influence brain function by participating at stages in metabolism of proteins, lipids, carbohydrates, other coenzymes and hormones. Vitamin B(6) participates in the metabolism of amino acids in the form of decarboxylation, transamination, deamination, racemization and desulfhydration reactions. The crucial roles that these coenzymes play in the maintenance of functional integrity of the brain become evident when one realizes that some compounds implicated as neurotransmitters are synthesized and/or metabolized by the aid of the vitamin B(6)-dependent enzymatic reactions. These include dopamine, norepinephrine and serotonin, tyramine, tryptamine, taurine, histamine, gamma aminobutyric acid, and even acetylcholine indirectly. In recent years, the above-mentioned biogenic amines have become of considerable interest to neurobiologists who are investigating the etiology and the pathological manifestations of many disorders of the central nervous system such as Parkinsonism, Huntington's chorea, minimal brain disfunction, schizophrenia, depression, sleep disorders and seizure disorders. Vitamin B(6) deficiency in these cases is characterized by anemia, growth retardation and alteration in neuronal function, including neuropathies, hyperirritability, hyperexcitability and convulsions. The importance of vitamin B(6) in the study of brain function assumes still greater significance when one considers the effects of nutritional deficiencies on growth and development of the brain and mental processes and in the involvement of vitamin B(6) in some inborn errors of metabolism which result in mental retardation. Vitamin B(6) deficiency results in a lowered concentration of Coenzyme A in blood, in reduced absorption and storage of vitamin B(12), and in increased excretion of vitamin C. Furthermore, vitamin B(6) acts synergistically with vitamin E to control metabolism of unsaturated fats, with vitamin C in tyrosine metabolism and with niacin in its action and participates in niacin synthesis. In addition, vitamin B(6) deficiency results in insufficiency of insulin and in alteration of the functions of adrenal and pituitary glands, since it is involved in the synthesis of growth hormone, follicle-stimulating hormone, luteinizing hormone, aldosterone, glucagon, cortisol, estradiol, testosterone and epinephrine. It is hoped that by understanding the factors that regulate the synthesis, binding, storage and degradation of pyridoxal phosphate in the brain, a better insight into the role of vitamin B(6) in neurobiology may be gained.
 ...
PMID:Regulation and function of pyridoxal phosphate in CNS. 1964 63

In the International Classification of Sleep Disorders 2nd Edition (ICSD-2), sleep related rhythmic movement disorder (RMD) is classified as a disorder characterized by rhythmic movements of large muscle groups in different parts of the body. These are repetitive, stereotyped, rhythmic motor behaviors that occur predominantly during drowsiness or sleep,and are typically seen in infants and children. Episodes often occur at sleep onset, at any time during the night, and during quiet wakeful activities at a frequency of 0.5-2 sec), lasting <15 min. The prevalence is high in infants (59%), dropping to 5% at the age of 5 years. When persisting to older childhood or beyond, association with mental retardation, autism, or other significant pathology is reported. Few cases in adults of normal intelligence have been reported in the literature. There is a strong association with attention deficit hyperactivity disorder, suggesting a similar pathogenetic mechanism. There is also one adult case report occurring during strictly REM sleep. Mayer et al reported 24 subjects with RMD that persisted into adolescence and adulthood. Twenty of the subjects were adults, and 16 of them had the condition since childhood. Of these 20, 16 had no other sleep disorders (but 2 had a family history of RMD), and 4 had obstructive sleep apnea. This was the first ever report of familial RMD.
 ...
PMID:A multigenerational family with persistent sleep related rhythmic movement disorder (RMD) and insomnia. 2046 26

The aim of this study was to assess the presence of sleep breathing disorder and periodic leg movements during sleep (PLMS), and to evaluate NREM sleep instability in a group of children with mental retardation (MR) and epilepsy. Eleven subjects with MR and epilepsy (6 males, age range 9-17 years) were recruited for this study. A control group was formed by 11 age-matched normal children. Three children with MR and epilepsy showed an apnea-hypopnea index > 5, two of them had also a PLMS index > 5. Another subject had only a PLMS index > 5. Children with MR showed many sleep architecture differences compared to controls. They also showed higher cyclic alternating pattern (CAP) rate, increased A1 index, long and less numerous CAP sequences than controls. A detailed investigation and treatment of sleep disorders in children affected by MR and epilepsy may have a positive impact on seizure control.
 ...
PMID:Polysomnographic assessment of sleep disturbances in children with developmental disabilities and seizures. 2050 30


<< Previous 1 2 3 Next >>