Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038362 (stomatitis)
 8,852 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A boy born healthy, developed gastrointestinal symptoms (diarrhea, vomiting, ulcerative stomatitis) and megaloblastic anaemia with thrombocytopenia and neutropenia at the age of five weeks. Serum levels of folate and cobalamin were normal, but there was cobalamin-mal absorption. In his serum apo-TC2 was not detectable and immunoreactive total TC2 was very low (10% of normal values). Cultured skin fibroblasts failed to secrete functioning TC2. Pharmacological amounts of parenteral Cyanocobalamin, administered regularly, led to hematological remission and normal development. Interruption of therapy was followed by relapse within a few weeks. A coexisting hypogammaglobulinemia did not respond to cobalamin therapy at the selected dose level. A family investigation of serum TC2 concentrations and the genetic TC2 variants in 7 persons of three generations yielded evidence of autosomal-recessive inheritance of a silent TC2 allele (TC2 QLFL SEA-like). Three persons with heterozygous deficiency were asymptomatic.
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PMID:[Inherited transcobalamin-II-deficiency: clinical, genetic studies and diagnosis using cultured fibroblasts]. 666 2

The E3 ubiquitin ligase Casitas B cell lymphoma-b (Cbl-b) plays a critical role in the development of autoimmunity and sets the threshold for T cell activation. In the absence of Cbl-b, T cells stimulated via the TCR respond similarly to those that have received a CD28-mediated costimulatory signal, suggesting that the absence of Cbl-b substitutes for CD28-mediated costimulation. In this study, we show that loss of Cbl-b restores Ig class switching and germinal center formation in Vav1 mutant mice in response to an in vivo viral challenge. Genetic inactivation of Cbl-b also rescues impaired antiviral IgG production in CD28-mutant mice. Moreover, loss of CD28 results in disorganization of follicular dendritic cell clusters, which is also rescued by the Cbl-b mutation. Intriguingly, despite restored antiviral in vivo immunity and follicular dendritic cell clusters, loss of Cbl-b did not rescue germinal center formation in CD28-deficient mice. Mechanistically, in vivo vesicular stomatitis virus-induced IL-4 and IFN-gamma production and up-regulation of the inducible costimulatory molecule ICOS were dependent on CD28, and could not be rescued by the loss of Cbl-b. These data provide genetic evidence that CD28-dependent in vivo immune responses and Ig class switching can be genetically uncoupled from germinal center formation and ICOS induction by Cbl-b-Vav1-regulated signaling pathways.
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PMID:Differential control of CD28-regulated in vivo immunity by the E3 ligase Cbl-b. 1566 6

Cobalamin (vitamin B12 [Cbl]) is an essential cofactor for many biochemical pathways. Transcobalamin (TC) is required to internalize Cbl into the cells through membrane receptor-mediated endocytosis. Cbl is then processed in the cytoplasm and mitochondria by complementation factors leading to its active metabolites; methylcobalamin and 5-deoxyadenosyl-cobalamin. Deficiency of TC results in an elevation in methylmalonic acid and homocysteine. Patients usually present with macrocytic anemia, pancytopenia, failure to thrive, gastrointestinal symptoms, and neurological dysfunction. In this study, we report 4 patients from 2 unrelated families, with confirmed diagnosis of TC deficiency. Patients initially had a typical presentation of TC deficiency: severe diarrhea and vomiting, recurrent infections, stomatitis, macrocytic anemia, and neutropenia. Interestingly one of the patients was diagnosed at 3 months of age and developed ataxic gait related to cerebellar atrophy at the age of 14 months. His elder affected sibling was diagnosed at 5 months of age was completely normal. Two sibs, diagnosed at 2 months of age and immediately after birth, had autism spectrum disorder. Molecular investigations showed 2 novel mutations in TCN2 gene. Patients were treated and stayed stable on weekly injection of Cbl. In conclusion, TC deficiency has a wide heterogeneity in clinical phenotype, genotype, laboratory, and radiologic findings. Early detection of the disease and early initiation of aggressive parenteral treatment is probably associated with better prognosis and disease control.
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PMID:Long-term Outcome of 4 Patients With Transcobalamin Deficiency Caused by 2 Novel TCN2 Mutations. 2853 14