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)

Chondrodysplasia Punctata is a disease belonging to the metaphysia syndrome. This disease is characterized by endochondral punctata calcification of epiphysis or apophysis, short legs and hands, arthrogryposis, saddle nose, ichthyosis, cataract and mental retardation. This report concerns a case of Chondrodysplasia Punctata (Rhizomeric form) in a 4 year 1 month old girl. Observations were made from the dental point of view, and the findings were as follows: 1) The mesio-distal and bucco-lingual lengths of all primary teeth were smaller than the standard size. 2) Measuring the dental cast, the width of the dental arch was found to be larger, but the length of the arch was found to be smaller than the standard size. 3) The value of the palatal height was slightly smaller, compared with that of the normal children. 4) According to X-ray cephalometric analysis, the growth of the mandible was insufficient. 5) An enlargement of the angles of the teeth axes of the upper and lower central incisors was found. 6) The growth of the basal arches of the maxilla and mandible were shown to be retarded in the anterior portion. 7) Measurement of the area of the tubella sella triangle, revealed the posterior parts to be large and almost standard in the mesofacial part, and small in the mandibulo-facial parts.
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PMID:[Dental findings in a case of Chondrodysplasia Punctata]. 213 55

Endemic cretinism has been classified into neurological and myxedematous types. Profound mental deficiency, deaf-mutism and cerebral diplegia are predominantly found in the former. The latter have been described as less mentally retarded but with severe growth retardation and myxedematous features. The pathogenesis of different clinical types of endemic cretinism is still unclear. Recently, a unifying hypothesis suggested that iodine deficiency, severe enough to cause maternal and fetal hypothyroxinemia, results in neurological defects in all cretins. We conducted the present study in northern Thailand to determine the validity of this hypothesis in another geographical area. The study consisted of a multidisciplinary survey on 112 endemic cretins aged 2-66 years in Nan. They were categorized clinically into three types of endemic cretins, neurological (n = 57), myxedematous (n = 19) and mixed form (n = 36). The subjects were generally short and the majority had severe mental retardation (mean intellectual quotient (I.Q.) 30.8 +/- 8.8), psychomotor defect and profound sensorineural hearing loss. The I.Q. score and proportion of cretins with sensorineural hearing loss and psychomotor defect were similar among the three types of cretins. The most frequent neurological abnormalities were spasticity, hyper-reflexia, the presence of primitive reflexes and gait disturbance. These abnormalities were distributed equally among the three types of endemic cretins. Delayed skeletal maturation and abnormal epiphysis were also present in all types of cretins. However, myxedematous cretins were shorter (P < 0.01), having more myxedematous features (P < 0.05 to P < 0.001) and less sexual maturation (P < 0.05). Thyroid volume was lower in cretins with hypothyroidism (P < 0.01). In conclusion, our findings support the hypothesis that neurological features are present in all types of cretins, and are the consequence of maternal and fetal hypothyroxinemia due to severe iodine deficiency. The clinical manifestations of the cretins were subsequently modified by the length and severity of postnatal iodine deficiency and hypothyroidism.
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PMID:Endemic cretinism in Thailand: a multidisciplinary survey. 936 97

Mucopolysaccharidosis type VII (MPS VII) is a heritable lysosomal storage disease caused by a deficiency in beta-glucuronidase (GUSB) activity, leading to progressive accumulation of undegraded glycosaminoglycans in many tissues. Clinical features include growth and mental retardation, hearing and visual defects, shortened lifespan, and skeletal deformities. A murine model of MPS VII has been described that shares many of the manifestations of the human disease, including the skeletal dysplasia. In this study we describe abnormalities in the cellular morphology and function of osteoclasts and a localized defect in bone formation rate in the MPS VII mouse. Ultrastructural analysis revealed that MPS VII osteoclasts fail to form ruffled border membranes and many appeared to be detached from the bone surface. Following bone marrow transplantation, osteoclasts derived from wild-type donors showed normal morphology and were closely associated with the bone surface in MPS VII recipients. In vitro bone resorption assays demonstrated that MPS VII osteoclasts formed significantly smaller and fewer pits than those formed by osteoclasts derived from normal mice of the same strain. Although osteoclast morphology and function appeared to be abnormal in the MPS VII mouse, interleukin-1 (IL-1)-induced osteoclastogenesis in vivo was not affected. In addition to the osteoclast defects, MPS VII mice demonstrated a slower rate of bone matrix deposition in the epiphysis by in vivo calcein labeling experiments. These data suggest that abnormal morphology and function of MPS VII osteoclasts, combined with deficient matrix deposition, may contribute to the skeletal defects observed in this lysosomal storage disease.
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PMID:Abnormal osteoclast morphology and bone remodeling in a murine model of a lysosomal storage disease. 1185 42

Prader-Willi syndrome (PWS) is characterized by hypotonia, obesity, hypogonadism, small hands and feet, and mental deficiency. Obesity and hypogonadism are also frequently associated with slipped capital femoral epiphysis (SCFE), suggesting that children with PWS might be at increased risk of developing SCFE. Members of the Prader-Willi Syndrome Association (U.S.A.) were surveyed regarding the history of orthopaedic problems in general and of SCFE in particular. A total of 565 (63%) responses were received. The prevalence of orthopaedic conditions included 47% with flat feet, 41% with scoliosis, 19% with knock knees, 10% with hip dysplasia, 9% with osteoporosis, 7% with patellofemoral instability, 3% with bowlegs, 2% each with clubfeet, nursemaid's elbow, or leg-length inequality, and one patient (0.2%) with SCFE. The results of the survey indicate that SCFE is uncommon in patients with PWS, but the prevalence of hip dysplasia is increased approximately 10-fold compared with the general population.
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PMID:High incidence of hip dysplasia but not slipped capital femoral epiphysis in patients with Prader-Willi syndrome. 1530 8

We describe a two and half year old male child with acrodysostosis, presenting with nasal hypoplasia, peripheral dysostosis (gross shortening of hands and feet), cone-shaped epiphysis, advanced bone age, and mental retardation. He and his mother also had bilateral first ray hyperplasia of the feet thereby expressing the autosomal dominant inheritance pattern.
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PMID:Acrodysostosis: autosomal dominant transmission. 1614 86