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)

A 35 year-old male was admitted to our hospital because of convulsive seizures. His parents are first cousins. No other members of his family have similar symptoms. He showed mental retardation since childhood. At age 14, he had generalized convulsive seizures that were intractable. Bilateral cataracts were found and extracted at age 18. He noticed bilateral swellings at Achilles tendons at around 25 years of age. Physical examination revealed bilateral swellings of Achilles tendons. Neurologically, he showed poor intellectual ability, hyperreflexia with positive Babinski's sign and cerebellar ataxia. Marked elevations of cholestanol level (53.84 micrograms/ml; normal: 2.71 +/- 0.81, n = 17) and cholestanol/cholesterol ratio (2.20%; normal: 0.16 +/- 0.05, n = 17) were detected in serum. EEG showed abnormal background activities with bursts of high voltage slow theta activities. MRI study showed high intensity lesions in globus pallidus and multiple lesions in white matter with long spin echo sequence. Oral administration of chenodeoxycholic acid improved EEG findings, serum cholestanol level and convulsive seizures. However, the MRI abnormalities remained unchanged, which suggested irreversible brain damage. We reviewed the previous reports of 144 cases of CTX. Fourteen cases had convulsive seizures. We stress that CTX is one the causes of symptomatic epilepsy.
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PMID:[A case of cerebrotendinous xanthomatosis with convulsive seizures]. 219 Jul 43

Alkaline phosphatase (ALP) in humans comprises a family of four cell-surface phosphomonoester phosphohydrolase isozymes. Three genes separately encode the "tissue-specific" ALPs whereas the fourth gene encodes ubiquitous homodimeric "tissue-nonspecific" ALP (TNSALP) richly expressed in bone, liver, kidney, and developing teeth. TNSALP monomers have five putative N-linked glycosylation sites where different post-translational modifications account for this isozyme's distinctive physicochemical properties in different organs. Three bone-derived TNSALP (BALP) isoforms (B/I, B1, and B2) are present in healthy serum, whereas a fourth BALP isoform (B1x) can circulate in chronic kidney disease. Herein, we report a healthy boy with persistent hyperphosphatasemia due to BALP levels two- to threefold higher than age-appropriate reference values. High-performance liquid chromatography, electrophoresis, heat inactivation, catalysis inhibition, and polyethylene glycol precipitation revealed increased serum B/I, B1, and B2 differing from patterns found in skeletal diseases. B/I was ~23-fold elevated. Absence of mental retardation and physical stigmata excluded Mabry syndrome, the ALP-anchoring disorder causing hyperphosphatasemia. Routine biochemical studies indicated intact mineral homeostasis. Serum N-terminal propeptide of type I procollagen (P1NP) level was normal, but C-terminal cross-linking telopeptide of type I collagen (CTX) level was elevated. However, radiological studies showed no evidence for a generalized skeletal disturbance. Circulating pyridoxal 5'-phosphate, a TNSALP natural substrate, was not low despite the laboratory hyperphosphatasemia, thereby suggesting BALP phosphohydrolase activity was not elevated endogenously. Mutation analysis of the ALPL gene encoding TNSALP revealed no defect. His non-consanguineous healthy parents had serum total ALP activity and BALP protein levels that were normal. Our patient's sporadic idiopathic hyperphosphatasemia could reflect altered post-translational modification together with increased expression and/or impaired degradation of BALP.
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PMID:Persistent idiopathic hyperphosphatasemia from bone alkaline phosphatase in a healthy boy. 3247 45