Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025362 (mental retardation)
 15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Prenatal exposure of human brain to ethanol impairs neuronal migration and differentiation and causes mental retardation. The present results indicate that the adverse effects of ethanol on brain development may be partly due to the ethanol-induced disturbance of neuronal interaction with laminin, a protein involved in neuronal migration and axon guidance. This report shows that physiological concentrations (IC50 = 28 mM) of ethanol inhibit neurite outgrowth and neuronal migration of the rat cerebellar granule neurons on a laminin substratum. The ethanol-treated granule neurons undergo apoptosis, degrade their laminin substratum, and appear to release and bind increased amounts of the B2-chain-derived peptides along their surfaces. A protease inhibitor aprotinin, and the NMDA receptor channel, and voltage-gated calcium channel antagonist MK801 partially protect cerebellar granule neurons from ethanol-induced neurotoxicity. These results imply that ethanol-treated granule neurons resemble the granule neurons of the homozygous weaver mouse cerebellum with respect to their apoptosis, laminin expression, and partial rescue by approtinin and MK-801. Thus, ethanol may influence neuronal survival and neurite outgrowth via molecular pathways similar to those involved in neuronal death in other neurodegenerative processes of the central nervous system.
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PMID:Ethanol-exposed central neurons fail to migrate and undergo apoptosis. 918 67

Fragile X syndrome is a common form of inherited mental retardation caused by the absence of the fragile X mental retardation protein (FMRP). It has been hypothesized that FMRP is involved in the processing and/or translation of mRNAs. Human and mouse target-mRNAs, containing purine quartets, have previously been identified. By using cDNA-SELEX (systematic evolution of ligands by exponential enrichment), we identified another class of human target-mRNAs which contain U rich sequences. This technique, in contrast to oligonucleotide-based SELEX, allows the identification of FMRP targets directly from mRNA pools. Many of the proteins encoded by the identified FMRP targets have been implicated in neuroplasticity. Steady state levels of target-mRNAs were unchanged in the brain of fragile X mice. However, levels of two target-encoded proteins, an L-type calcium channel subunit and MAP1B, were downregulated in specific brain regions suggesting a defect in the expression of target-encoded proteins in fragile X syndrome.
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PMID:The fragile X mental retardation protein binds and regulates a novel class of mRNAs containing U rich target sequences. 1292 6

The purpose of this paper was to present the case of a two-year-old male diagnosed with Timothy syndrome who presented with generalized enamel defects in the primary dentition. Timothy syndrome is an autosomal dominant condition characterized by a de novo missense mutation in the Cav1.2 L-type calcium channel CACNA1C. Timothy syndrome patients present with multiple clinical manifestations, including: cardiac arrhythmias; syndactyly; immune deficiency; intermittent hypoglycemia; and neurologic issues, including seizures, mental retardation, hypotonia, and autism. Craniofacial abnormalities reported include: low-set ears; flat nasal bridge; small upper jaw; thin upper lip; round face; and baldness at birth. Abnormalities in the dentition have been reported, including small, misplaced teeth with poor enamel and severe caries. At present, there is no thorough description of the dental abnormalities seen in a patient with Timothy syndrome.
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PMID:Dentition abnormalities in a Timothy syndrome patient with a novel genetic mutation: a case report. 2496 Mar 93