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)

A 14-year-old boy was found to excrete excessive amounts of acidic glycosaminoglycans which were predominantly chondroitin 4-sulfate and chondroitin 6-sulfate. Clinical features included dwarfism, mental retardation, coarse facies, deformities of the spine, hip joints and thorax, and granulations in leucocytes. The clinical and biochemical features found in this boy were compared with the known types of mucopolysaccharidosis and it has been concluded that this case is a new type of mucopolysacchariduria.
 ...
PMID:Chondroitin 4- and 6-sulfaturia: a new type of inborn error of metabolism? 10 12

Three atypical patients with clinical and laboratory findings of Hurler syndrome, but without alpha-L-iduronidase deficiency, are described. Clinical features included characteristic facies, mental retardation, corneal clouding, dysostosis multiplex, restriction of joint mobility, and hepatosplenomegaly. Excessive amounts of chondroitin sulfate B and heparitin sulfate were excreted in the urine. alpha-L-Iduronidase activities in leucocytes and liver tissues were within the normal range or somewhat elevated.
 ...
PMID:Atypical Hurler syndrome without alpha-L-iduronidase deficiency. 13 68

The Dyggve-Melchior-Clausen (DMC) syndrome includes short stature, dwarfism, mental retardation, and skeletal abnormalities especially in the spine and the extremities resembling the findings in the mucopolysaccharidoses. A particular abnormality is the "lace border" found on radiological examination of the iliac crest. The three original cases have been followed for 15--20 years and the course is characterized by increasing mental retardation and motor disability whereas the "lace border" is less pronounced than before. A survey of 17 other cases is given and similarities and differencies to the mucopolysaccharidoses are pointed out. Patients with the DMC syndrome have been suggested to be deficient in an enzyme cleaving glycoprotein-acid mucopolysaccharide (AMP) linkage. We have previously found in DMC patients, an abnormal excretion of urinary AMP's of which some were undersulfated and some were oversulfated. Lysosomal acid proteinase, i.e., cathepsin D and neutral proteinases: elastase and cathepsin G were found to be normal in DMC patients. However, alfa2-macroglobulin in serum was raised. This increase may cause an inhibition of the neutral proteinases. An increased level of chondroitin sulfate N-acetylgalactosamine-6-sulfate-sulfatase and decreased enzymic levels of aryl sulphatase A and B (assayed with p-nitrocatecholsulfate as a substrate) were found in leucocytes of DMC patients. Metabolic studies have revealed an unbalanced incorporation of glycoprotein AMP-precursors in DMC lymphocytes. All in all the data suggests the DMC syndrome to be an inborn error of glycoprotein-AMP-metabolism.
 ...
PMID:The Dyggve-Melchior-Clausen (DMC) syndrome. A 15 year follow-up and a survey of the present clinical and chemical findings. 57 40

The metabolism of ground substance in connective tissue of an 18-year-old boy with oculo-cerebro-renal syndrome was studied. He had characteristic clinical and laboratory findings described by Lowe et al. such as growth retardation, mental deficiency, glaucoma, cataracta, decreased muscle tone, metabolic acidosis, aminoaciduria and osteomalacia. The urinary excretion of acid glycosaminoglycans and of total hydroxyproline were 27 mg/day (as glucuronic acid) and 280 mg/day respectively on admission. Both values decreased to the upper limits of normal level transiently during treatment with alkali and vitamin D2. At that time, an improvement in bone abnormalities, a decrease of serum alkaline phosphatase, and an elevation of serum inorganic phosphate were observed. The therapy prevented him from progressive osteomalacia and cured him of it, but mucopolysacchariduria and hydroxyprolinuria did not disappear. Analytical electrophoresis on cellulose acetate sheets showed that urinary acid glycosaminoglycans were composed of undersulfated chondroitin 4-/6-sulfate and heparan sulfate with a ratio of 6:4, on admission. After oral administration of alkali, the excretion of heparan sulfate decreased and undersulfated chondroitin 4-/6-sulfate was determined as a main component of urinary acid glycosaminoglycans. The clinical and laboratory data in this case suggested that the increased excretion of acid glycosaminoglycans and total hydroxyproline was caused by abnormal metabolism in connective tissues, especially by the bone abnormalities, in this syndrome.
 ...
PMID:Urinary excretion of acid glycosaminoglycans and hydroxyproline in a patient with oculo-cerebro-renal syndrome. 73 46

The Dyggve-Melchior-Clausen syndrome is an inherited disorder of skeletal development characterized by short-trunked dwarfism, mental retardation, and a distinctive pattern of bone changes. The radiographic features seen in the 15 patients described in this report include platyspondyly with notched end plates of the vertebral bodies, small ilia with broad, frequently lacy crests, lateral displacement of the capital femoral epiphyses, and accessory ossification centers of the first metacarpals, proximal and middle phalanges. Cytological and biochemical data, notably a normal sulfate incorporation into acid mucopolysaccharides of cultured fibroblasts, indicate that the Dyggve-Melchior-Clausen syndrome is not a mucopolysaccharidosis as has been previously suggested.
 ...
PMID:The Dyggve-Melchior-Clausen syndrome. 80 18

The mucopolysaccharidoses are genetic disorders of glycosaminoglycan metabolism. Patients with these diseases accumulate within the lysosomes of most tissues excessive amounts of dermatan and/or heparan sulfates, or of keratan sulfate. The clinical consequences of such glycosaminoglycan storage range from skeletal abnormalities to cardiovascular problems, and to motor and mental retardation. In all mucopolysaccharidoses, except Morquio disease, an excessive accumulation of sulfate-labeled glycosaminoglycans has been demonstrated in fibroblasts cultured from the patient's skin. It was subsequently shown that this was due to the deficiency of specific proteins which were named "corrective factors", because their addition to the culture medium effected a normalization of the impaired glycosaminoglycan catabolism in the respective mucopolysaccharidosis fibroblasts. The investigation of the function of the corrective factors, and other studies, led to the identification of the enzymatic defect in each of the mucopolysaccharidoses. Seven lysosomal enzyme deficiencies are now recognized among this group of disorders. A classification of the diseases, according to the mutant gene products, reveals that there is considerable phenotypic variation not only between diseases, but also within several disease types. With the availability of the appropriate enzyme assays, the previous difficulties in diagnosing these disorders have now been overcome. Methods are also available for the prenatal diagnosis, and the detection of heterozygous individuals, in most of the mucopolysaccharidoses. Although correction of the metabolic defect through enzyme replacement has been achieved in tissue culture, many problems remain to be solved before such therapy may become applicable in the patients themselves.
 ...
PMID:The mucopolysaccharidoses: inborn errors of glycosaminoglycan catabolism. 82 Jun 26

A case is reported with a syndrome characterized by mental retardation, choreoathetosis, high levels of uric acid and aggressive, selfmutilation behavior, diagnosed as Lesch-Nyhan's syndrome. The most important features are, its appearance confined only to males, the absence of abnormalities along the prenatal and newborn periods, as well as the progressive impairment in the clinical course of the patient. The presence of high blood levels of uric acid which was controlled with the administration of allopurinol, the anemia, treated with ferrous sulfate and the complete absence of the AGPRT enzyme, were the laboratory findings. The clinical, pathophysiological and biochemical aspects of the treatment were also reviewed, as well as the experiences and findings reported in other series. The authors stress the very low frequency of these cases, the importance of making the diagnosis and the exceptional and eccentricity of the features which are part of the syndrome, such as the bites.
 ...
PMID:[Lesch-Nyhan syndrome. Report of a case]. 87 31

Cysteine-S-sulfate is an abnormal metabolite discovered in the urine and blood of a patient with cysteine oxidase deficiency, a rare disorder of sulfur amino acid metabolism associated with brain damage and mental retardation. The molecular structure of cysteine-S-sulfate closely resembles that of glutamate and related acidic amino acids which have both neuroexcitatory and neurotoxic properties (excitotoxic amino acids). Here we demonstrate that cysteine-S-sulfate induces the glutamate type of neuropathology in the rat central nervous system when administered subcutaneously to infants or intracerebrally to adults. It is postulated that cysteine-S-sulfate may be the neurotoxic agent responsible for brain damage in sulfite oxidase deficiency. The possibility that other excitotoxic amino acids could play occult roles in other unexplained neuropathologic conditions is discussed.
 ...
PMID:Cysteine-S-sulfate: brain damaging metabolite in sulfite oxidase deficiency. 112 50

We report an adolescent patient with Prader-Willi syndrome accompanying suppressible hypergonadotropism. The subject is an 18-year-old female. She was obese (body mass index: 35.7) and hypomyotonic with mental retardation. On endocrinological examination, a high serum LH concentration and hyperresponsiveness of luteinizing hormone (LH) to intravenously administered LH-Releasing Hormone (LH-RH) were observed, while the basal follicle stimulating hormone level was within the normal range. In addition, serum dehydroxyepiandrosterone sulfate (DHEA-S) was also increased. Following 2 mg dexamethasone administration for 7 days, serum LH and DHEA-S were almost normalized and hyperresponse of LH to LH-RH completely disappeared. The present study provides evidence that altered responsiveness to adrenal steroid may be involved in the establishment of hypergonadotropinism in an adolescent patient with Prader-Willi syndrome.
 ...
PMID:Dexamethasone suppressible hypergonadotropism in an adolescent patient with Prader-Willi syndrome. 214 67

A case report of an 11-year-old Caucasian boy with the fragile X syndrome is presented. The fragile X syndrome is a form of X-linked mental retardation with a connective tissue component that involves mitral valve prolapse. Antibiotic prophylaxis, electrocardiographic abnormalities, and special anesthetic management considerations are elements of treating patients with fragile X syndrome. The patient received morphine sulfate and scopolamine as a preoperative premedication. Ketamine was also administered intramuscularly prior to induction to gaseous anesthetic. Pancuronium was used to facilitate nasotracheal intubation. A wandering atrial pacemaker and progressive hypocapnia, both of which were managed without complication, were the only problems encountered in the anesthetic procedure.
 ...
PMID:General anesthesia and fragile X syndrome: report of a case. 293 7


1 2 3 4 5 6 Next >>