Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Twenty-three children surviving more than 5 years from the diagnosis of leukemia, lymphoma, or malignant histiocytosis were evaluated for clinical evidence of central nervous system disease. Severe impairment, consisting of seizures, paraplegia, and dementia was present in 4, all of whom received methotrexate (MTX) and other agents for 2 to 7 years. Brain biopsies in 3 of these children showed white-matter gliosis and no evidence of viral or other infections or leukemic infiltrates. Of the remaining children 10/19 were found to have mild clinical or EEG abnormalities. All had received i.v. MTX with other drugs for 2-6 years; 5 did not receive cranial irradiation. Common to all impaired patients was the administration of intravenous methotrexate in relatively high doses over a prolonged period of time. Impairment in nervous system function may present as a spectrum of deficiencies, with the most severe resulting in death, or as in the 4 patients described here, profound dementia and dependence. Less dramatic changes in functioning, may, however, result from various combinations of chemotherapy and radiation therapy. Methods of assessing their etiology and impact on survivors need now to be devised.
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PMID:Effects of chemotherapy on the central nervous system. A study of parenteral methotrexate in long-term survivors of leukemia and lymphoma in childhood. 76 54

During maintenance therapy with intraventricular methotrexate, progressive dementia developed in a child with meningeal leukemia. Cerebrospinal fluid levels of MTX were in the nontoxic range and neurologic evaluation failed to demonstrate anatomic obstruction, infection, or folate depletion. The patient's symptoms gradually resolved when the methotrexate was discontinued, suggesting that methotrexate neurotoxicity may occur in the absence of an elevated CSF concentration of MTX.
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PMID:Reversible dementia temporally associated with intraventricular therapy with methotrexate in a child with acute myelogenous leukemia. 106 Jul 45

Down syndrome (DS) is a major cause of congenital heart and gut disease and mental retardation. DS individuals also have characteristic facies, hands, and dermatoglyphics, in addition to abnormalities of the immune system, an increased risk of leukemia, and an Alzheimer-like dementia. Although their molecular basis is unknown, recent work on patients with DS and partial duplications of chromosome 21 has suggested small chromosomal regions located in band q22 that are likely to contain the genes for some of these features. We now extend these analyses to define molecular markers for the congenital heart disease, the duodenal stenosis, and an "overlap" region for the facial and some of the skeletal features. We report the clinical, cytogenetic, and molecular analysis of two patients. The first is DUP21JS, who carries both a partial duplication of chromosome 21, including the region 21q21.1-q22.13, or proximal q22.2, and DS features including duodenal stenosis. Using quantitative Southern blot dosage analysis and 15 DNA sequences unique to chromosome 21, we have defined the molecular extent of the duplication. This includes the region defined by DNA sequences for APP (amyloid precursor protein), SOD1 (CuZn superoxide dismutase), D21S47, SF57, D21S17, D21S55, D21S3, and D21S15 and excludes the regions defined by DNA sequences for D21S16, D21S46, D21S1, D21S19, BCE I (breast cancer estrogen-inducible gene), D21S39, and D21S44. Using similar techniques, we have also defined the region duplicated in the second case occurring in a family carrying a translocation associated with DS and congenital heart disease. This region includes DNA sequences for D21S55 and D21S3 and excludes DNA sequences for D21S47 and D21S17.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Down syndrome: molecular mapping of the congenital heart disease and duodenal stenosis. 153 Nov 66

Retroviruses contain a reverse transcriptase in the virion that converts viral genomic RNA to proviral DNA. Retroviruses are divided into three groups; oncovirus, lentivirus, and spumavirus. The oncovirus group contains HTLV-1, which causes adult T-cell leukemia, encephalomyeloneuropathy, arthritis, and alveolo-bronchopathy. The lentivirus groups contains HIV, which causes acquired immunodeficiency syndrome and dementia. The genomic structures and functions of HTLV-1 and HIV have been demonstrated to explain the pathogenesis of these retroviruses.
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PMID:[Basic understanding of retroviruses]. 163 36

Alzheimer's disease is one of several brain disorders under the broad category of dementia. It is a gradually debilitating illness with no known cure. The first symptom is usually a slowly increasing memory loss, beginning between 40 and 65 years of age. As the disease progresses, the brain begins to deteriorate more rapidly, until it literally stops functioning. Of great concern is the projection that the number of people who will have Alzheimer's disease will double by the year 2030 because of the rising elderly population. Treating this population will escalate from the current estimate in excess of $2.5 billion to more than $6 billion. Speculation toward the increasing costs in money and workforce has led to an accelerated program in search of a cure or at least a symptomatic therapy for this condition. One of the most promising research leads is the striking connection between Alzheimer's disease and Down's syndrome and certain cancers: --Virtually 100% of patients with Down's syndrome who survive past age 35 show the same mental deterioration and identical brain changes seen in patients with Alzheimer's disease, including the presence of plaque and neurofibrillary tangles.--The presence of a high percentage of Down's syndrome among relatives of patients with Alzheimer's disease. --A high incidence of certain types of syndrome and among relatives of people who have Alzheimer's disease, such as leukemia, lymphomas, Hodgkin's disease, and immune system disorders. The key to the intercorrections between Alzheimer's disease and Down's syndrome seems to be a genetic component related to chromosome 21.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Alzheimer's disease: an emerging affliction of the aging population. 293 67

Unexplained debilitating dementia or encephalopathy occurs frequently in adults and children with the acquired immune deficiency syndrome (AIDS). Brains from 15 individuals with AIDS and encephalopathy were examined by Southern analysis and in situ hybridization for the presence of human T-cell leukemia (lymphotropic) virus type III (HTLV-III), the virus believed to be the causative agent of AIDS. HTLV-III DNA was detected in the brains of five patients, and viral-specific RNA was detected in four of these. In view of these findings and the recent demonstration of morphologic and genetic relatedness between HTLV-III and visna virus, a lentivirus that causes a chronic degenerative neurologic disease in sheep, HTLV-III should be evaluated further as a possible cause of AIDS encephalopathy.
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PMID:HTLV-III infection in brains of children and adults with AIDS encephalopathy. 298 29

Methotrexate may cause seizures, dementia, and leukoencephalopathy when given in toxic doses to children with leukemia or solid tumors. Even in therapeutic doses, treatment with this drug is associated with an increased incidence of seizures in children with leukemia. To study mechanisms of injury, juvenile rats were given multiple intraventricular injections of methotrexate and the brains were analyzed for histopathology and biogenic amine metabolites of dopamine and serotonin. Disruption of monoamine metabolism has been proposed as a cause of brain dysfunction from this chemotherapy. Multiple injections (1 or 2 mg/kg) produced convulsions in an increasingly larger percentage of animals at higher cumulative doses, and five doses produced the neuropathological changes seen in human leukoencephalopathy. A single dose reduced the concentration of brain metabolites of dopamine, but not serotonin, six hours later. The effect was less pronounced after five doses. This rodent model should be useful for studying the metabolic basis of methotrexate encephalopathy.
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PMID:A model of methotrexate encephalopathy: neurotransmitter and pathologic abnormalities. 359 35

Progressive presenile dementia with lipomembranous polycystic osteodysplasia was first described by Jarvi and Hakola in an isolated region of Finland. We report the occurrence of this disorder in 4 of 10 siblings in an American family of Czechoslovakian ancestry. Characteristics of the disease include multiple bone cysts with pathologic fractures, progressive dementia with seizures and abnormal EEG, calcification of basal ganglia, and death in the fourth to six decades. Autosomal-recessive inheritance is likely. Electronmicroscopy of fat cells reveals peculiar membrane convolutions. Limited neuropathologic material has shown gliosis and demyelination of white matter, senile plaques, and neurofibrillary tangles. Leukemia and a disorder of intestinal motility may be associated findings. Prevalence of the disorder is unknown, partly because it may be confused with Alzheimer disease and fibrous dysplasia of bone. Radiographs of hands and feet should be part of the evaluation of patients with unexplained presenile dementia.
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PMID:Lipomembranous polycystic osteodysplasia (brain, bone, and fat disease): a genetic cause of presenile dementia. 668 64

From 1972-1974, 228 children began treatment for acute lymphocytic leukemia and were prospectively assessed for neurologic complications. After CNS irradiation (2,400 rad) and intrathecal methotrexate (MTX), they received weekly intravenous maintenance therapy with MTX alone (40-60 mg/m2; 20 patients) or MTX (10-30 mg/m2) with other drugs (208 patients). Signs of leukoencephalopathy appeared in 11 children (nine without CNS leukemia) after 4-15 months of IV MTX alone, and included lethargy, seizures, spasticity, paresis, drooling, and dementia. Before or during the clinical onset, EEG frequencies slowed (all ten patients tested). Radionuclide scans showed periventricular accumulation of 99mTc (9/11 patients) and remained abnormal for greater than or equal to six months in eight patients. Cranial computed tomograms or neuropathology findings (five patients each) demonstrated leukoencephalopathy (nine patients) and radiation-related microangiopathy (ten patients). Severe neurologic and neuropsychologic dysfunctions were present in four long-term survivors.
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PMID:Progression of methotrexate-induced leukoencephalopathy in children with leukemia. 693 56

Down syndrome (DS) is a major cause of mental retardation and congenital heart disease. Besides a characteristic set of facial and physical features, DS is associated with congenital anomalies of the gastrointestinal tract, an increased risk of leukemia, immune system defects, and an Alzheimer-like dementia. Moreover, DS is a model for the study of human aneuploidy. Although usually caused by the presence of an extra chromosome 21, subsets of the phenotypic features of DS may be caused by the duplication of small regions of the chromosome. The physical map of chromosome 21 allows the molecular definition of the regions duplicated in these rare cases of partial trisomy. As a first step in identifying the genes responsible for individual DS features and their pathophysiology, a panel of cell lines derived from 16 such individuals has been established and the molecular break points have been determined using fluorescence in situ hybridization and Southern blot dosage analysis of 32 markers unique to human chromosome 21. Combining this information with detailed clinical evaluations of these patients, we have now constructed a "phenotypic map" that includes 25 features and assigns regions of 2-20 megabases as likely to contain the genes responsible. This study provides evidence for a significant contribution of genes outside the D21S55 region to the DS phenotypes, including the facies, microcephaly, short stature, hypotonia, abnormal dermatoglyphics, and mental retardation. This strongly suggests DS is a contiguous gene syndrome and augurs against a single DS chromosomal region responsible for most of the DS phenotypic features.
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PMID:Down syndrome phenotypes: the consequences of chromosomal imbalance. 819 71


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