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

Oral and peri-oral structures can be traumatized by self-injurious behavior (SIB). Various articles have described prostheses used to prevent SIB-related injuries to the oral tissues of patients who have developmental or medical problems, such as psychological problems, congenital syndromes or mental retardation; however, reports of oral SIB in individuals unaffected by the above conditions are scarce. This case report describes the use of a removable prosthesis to prevent a stress-induced cheek biting habit in 15-year-old girl who did not have any of the commonly related conditions. The report discusses the importance of designing a prosthesis that protects tissues, while considering injury severity and the patient's healthas well as her ability to cooperate with treatment.
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PMID:Prevention of habitual cheek biting: a case report. 1629 27

Defect of the purine salvage enzyme, hypoxanthine phosphoribosyl transferase (HPRT), results in Lesch-Nyhan disease (LND). It is unknown how the metabolic defect translates into the severe neuropsychiatric phenotype characterized by self-injurious behavior, dystonia and mental retardation. There are abnormalities in GTP, UTP and CTP concentrations in HPRT-deficient cells. Moreover, GTP, ITP, XTP, UTP and CTP differentially support Gs-protein-mediated adenylyl cyclase (AC) activation. Based on these findings we hypothesized that abnormal AC regulation may constitute the missing link between HPRT deficiency and the neuropsychiatric symptoms in LND. To test this hypothesis, we studied AC activity in membranes from primary human skin and immortalized mouse skin fibroblasts, mouse Neuro-2a neuroblastoma cells and rat B103 neuroblastoma cells. In B103 control membranes, GTP, ITP, XTP and UTP exhibited profound stimulatory effects on basal AC activity that approached the effects of hydrolysis-resistant nucleotide analogs. In HPRT- membranes, the stimulatory effects of GTP, ITP, XTP and UTP were strongly reduced. Similarly, in human and mouse skin fibroblast membranes we also observed a decrease in GTP-stimulated AC activity in HPRT-deficient cells compared with the respective controls. In mouse Neuro-2a neuroblastoma membranes, AC activity in the presence of GTP was below the detection limit of the assay. We discuss several possibilities to explain the abnormalities in AC regulation in HPRT deficiency that encompass various species and cell types.
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PMID:Decreased GTP-stimulated adenylyl cyclase activity in HPRT-deficient human and mouse fibroblast and rat B103 neuroblastoma cell membranes. 1633 32

Research into behavior problems among individuals with mental retardation has been well developed. However, few studies have addressed the effect of multiple problem behaviors on social skills. In the present study, the authors examined the relationship between two problem behaviors, stereotypy and self-injury, and social skills among individuals with profound mental retardation. A total of 120 participants were divided into four groups based on the presence of stereotypic and self-injurious behavior. Persons with comorbid stereotypy and self-injury evinced more negative nonverbal social skills than did those with self-injury alone or no problem behaviors. In the past, researchers examined behavior problems as isolated phenomena. However, a recent shift in the conceptualization of problem behaviors has exposed the lack of research regarding the nature of social and adaptive skills in the face of multiple topographies of problem behaviors using broader conceptualizations.
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PMID:The relationship of comorbid problem behaviors to social skills in persons with profound mental retardation. 1672 27

Lesch-Nyhan syndrome (LNS) is an X-linked genetic disorder resulting in hyperuricemia, choreoathetosis, mental retardation, and self-injurious behavior. It is caused by loss of activity of the ubiquitous enzyme hypoxanthine-guanine-phosphoribosyltransferase (HPRT). The biochemical analysis of residual HPRT activity in patients' red blood cells is the first step in LNS diagnosis, and it precedes molecular study to discover the specific mutation. Unfortunately, biochemical diagnosis of healthy carriers is difficult because HPRT enzymatic activity in blood cells is similar in LNS carriers and in healthy people; genetic tests can help reveal mutations at the genomic or cDNA level, whereas gross deletions involving the first or last exons of HPRT gene are not detectable. Until now, a test based on 6-thioguanine-resistant phenotype of HPRT mutant cells from LNS patients is the only method accepted for the diagnosis of any kind of mutation in carriers. In this work, we introduce a new approach to identify carriers of large deletions in HPRT gene using real-time PCR. Results were validated in a blinded manner with a linkage study and with results obtained in Italian families previously analyzed with selective medium test. Real-time PCR analysis clearly confirmed the results obtained by selective medium; linkage data strengthened real time results, allowing us to follow the allele with the mutated HPRT through the family pedigree. We hope that the real-time PCR approach will provide a useful and reliable method to diagnose LNS carriers of large deletions in HPRT gene.
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PMID:Real-time PCR and linkage studies to identify carriers presenting HPRT deleted gene. 1722 73

Prader-Willi syndrome (PWS) is a genetically determined neurodevelopmental disorder characterized by mental retardation and distinct physical, behavioral, and psychiatric features. Based on parents' questionnaires, we examined the prevalence of behavioral and psychiatric disorders of 165 persons with PWS aged 2-31 years in Japan. The data were analyzed comparing four different age groups with PWS: group 1, 2-5 years (n=34); group 2, 6-11 years (n=57); group 3, 12-17 years (n=45); and group 4, 18-31 years (n=29). Further, we compared the results of our PWS group 4 with those of 42 age-, gender-, and intelligence level-matched intellectual disability (ID) individuals without PWS. Our results showed that repetitive speech and stubbornness were prominent from early childhood and other behavioral problems such as hyperphagia, stealing food, temper tantrums, lying, and emotional lability tended to be more frequent with age among persons with PWS. Moreover, young adults with PWS have significantly higher rates of behavioral and psychiatric disorders than IDs without PWS, such as stubbornness, hyperphagia, temper tantrums, self-injurious behavior (skin picking), hypersomnia, inactivity, and delusion. Degree of obesity was not necessarily related to behavioral and psychiatric features associated with PWS. Our findings revealed that persons with PWS are more vulnerable to behavioral and psychiatric disorders particularly in young adulthood compared to those with ID from other etiologies in Japan.
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PMID:Behavioral and psychiatric disorders in Prader-Willi syndrome: a population study in Japan. 1731 21

Self-injurious behavior is deliberate harm to the body that may lead to factitious oral injuries. Management of patients with self-inflicted injury continues to be a challenge for the dental profession. The purpose of this article is to review clinical findings in a patient who presented with severe, painful gingival recession in the primary dentition. A case report of an 8-year-old girl with mental retardation is presented. The periodontal examination showed bilateral gingival recession of the mandibular canines and the mandibular first and second molars so severe that it was possible to clinically observe the exposed roots. The diagnosis of self-inflicted gingival lesions and self-injurious behavior was established. Although the lesions are no longer present, the self-injurious behavior persists. Psychologic support was suggested, and an oral removable appliance was fitted.
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PMID:Self-injurious behavior in a patient with mental retardation: review of the literature and a case report. 1769 2

The purpose of this preliminary study was to examine the morphology and neuropeptide density of epidermal nerve fibers quantified through skin biopsy samples from three adults with neurodevelopmental disorders and chronic self-injurious behavior (SIB) secondary to mental retardation compared with non-SIB normal IQ controls. A cross-sectional design was used with 3mm punch skin biopsies collected from each participant from non-self-injurious body sites and compared with site-matched existing normal control skin samples. The study was conducted at an outpatient clinic. The primary dependent measure for the morphology analyses was the coefficient of variation (CV) to quantify the mean gap length between epidermal nerve fibers for each subject. Visual microscopic examination and quantitative analysis of the microscopy images suggested there were morphological abnormalities (increased CV) in the epidermal nerve fibers among the chronic SIB cases. Substance P (SP) fiber density was increased with 2-3 times as many fibers in SIB subjects as control subjects. Additional empirical work is needed to clarify the relation between sensory innervation of the skin and self-injury to improve assessment and treatment outcomes.
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PMID:Evidence of altered epidermal nerve fiber morphology in adults with self-injurious behavior and neurodevelopmental disorders. 1785 Sep 69

Fragile X mental retardation is caused by silencing of the gene (FMR1) that encodes the RNA-binding protein (FMRP) that influences translation in neurons. A prominent feature of the human disorder is self-injurious behavior, suggesting an abnormality in pain processing. Moreover, FMRP regulates group I metabotropic glutamate receptor (mGluR1/5)-dependent plasticity, which is known to contribute to nociceptive sensitization. We demonstrate here, using the Fmr1 knock-out (KO) mouse, that FMRP plays an important role in pain processing because Fmr1 KO mice showed (1) decreased (approximately 50%) responses to ongoing nociception (phase 2, formalin test), (2) a 3 week delay in the development of peripheral nerve injury-induced allodynia, and (3) a near absence of wind-up responses in ascending sensory fibers after repetitive C-fiber stimulation. We provide evidence that the behavioral deficits are related to a mGluR1/5- and mammalian target of rapamycin (mTOR)-mediated mechanism because (1) spinal mGluR5 antagonism failed to inhibit the second phase of the formalin test, and we observed a marked reduction in nociceptive response to an intrathecal injection of an mGluR1/5 agonist (RS)-3,5-dihydroxyphenylglycine (DHPG) in Fmr1 KO mice; (2) peripheral DHPG injection had no effect in KO mice yet evoked thermal hyperalgesia in wild types; and (3) the mTOR inhibitor rapamycin inhibited formalin- and DHPG-induced nociception in wild-type but not Fmr1 KO mice. These experiments show that translation regulation via FMRP and mTOR is an important feature of nociceptive plasticity. These observations also support the hypothesis that the persistence of self-injurious behavior observed in fragile X mental retardation patients could be related to deficits in nociceptive sensitization.
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PMID:Decreased nociceptive sensitization in mice lacking the fragile X mental retardation protein: role of mGluR1/5 and mTOR. 1809 33

Self-mutilation is form of self-injurious behavior which is either low intensity, high frequency form seen in personality disorder and mental retardation or low frequency, highly destructive form which occurs in the context of psychosis or acute intoxications. We report a 32 yr-old male with bipolar affective disorder presenting with multiple acts of major self-mutilation during an episode of psychotic depression. At presentation he had broken upper central incisors, circular burn scar on right palm, crush injury of left index finger with avulsed nail and cut injury over glans penis. In view of his extreme self-mutilating behavior, he was administered electroconvulsive therapy on second day following which self-mutilating behavior improved after fourth ECT. After 8 ECT sessions, he was started on lithium carbonate with a serum level of 0.82 meq/L and haloperidol 15 mg/day and there was no recurrence of self-mutilating behavior during follow up after four months.
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PMID:[Electroconvulsive therapy for multiple major self-mutilations in bipolar psychotic depression]. 1856 Oct 53

Self-injurious behavior (SIB) has been observed in people with tuberous sclerosis complex (TSC), although the frequency of SIB in TSC is largely unknown. SIB is associated with intellectual and developmental disabilities, but there is no single cause of SIB. We retrospectively examined the frequency of SIB in a population of 257 patients with TSC and determined possible associations with SIB. We found a 10% frequency of SIB in our TSC population. When compared with patients without psychiatric symptoms, we identified a significantly higher rate of electroencephalographic interictal spikes in the left frontal lobe and a significantly lower number of tubers in the left occipital, parietal, and posterior temporal lobes. We also found that frequency of TSC2 mutation, history of infantile spasms, history of seizures, mental retardation, and autism are significantly associated with SIB.
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PMID:Self-injurious behavior and tuberous sclerosis complex: frequency and possible associations in a population of 257 patients. 1870 61


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