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1.
Michael L. Graham Jonathan J. Shuster Barton A. Kamen David L. Cheo Matthew P. Harrison Brigid G. Leventhal D. Jeanette Pullen V. Michael Whitehead 《Cancer chemotherapy and pharmacology》1992,31(3):217-222
Summary We enrolled children with acute lymphoblastic leukemia (ALL) in a Pediatric Oncology Group (POG) pilot study to monitor erythrocyte (RBC) methotrexate (MTX) and folate (F) levels before and during treatment. The mean value for RBCF at diagnosis was 0.86±0.46 nmol/ml RBC in the 214 patients who achieved remission and 1.21±0.74 nmol/ml RBC in the 10 patients who did not (P=0.020). Folate levels tended to increase during remission induction, but they dropped following an intensive consolidation with methotrexate to levels that were sustained throughout chemotherapy treatment. Methotrexate levels reached mean values of approximately 0.15 nmol/ml RBC at the end of an intensive methotrexate consolidation, then fell to levels that were sustained throughout maintenance therapy. There was a weak correlation between improved event-free survival and higher RBCMTX levels after consolidation, but no correlation was found between improved survival and the level of RBCMTX or RBCF during maintenance therapy. A larger study with more complete data is needed to determine whether RBCMTX or RBCF might be useful in predicting event-free survival in patients with ALL.This work was supported in part by grants from the National Cancer Institute and the National Institute of Health (CA-30969, CA-28476, CA29139, CA-159-89, and CA-33587) 相似文献
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Identification of two mutations in a compound heterozygous child with dihydrolipoamide dehydrogenase deficiency 总被引:1,自引:0,他引:1
Hong YS; Kerr DS; Craigen WJ; Tan J; Pan Y; Lusk M; Patel MS 《Human molecular genetics》1996,5(12):1925-1930
An infant girl with elevated blood lactate, pyruvate, and plasma
branched-chain amino acids was diagnosed with dihydrolipoamide
dehydrogenase (E3; dihydrolipoamide: NAD+ oxidoreductase, EC 1.8.1.4)
deficiency. Activities of the pyruvate dehydrogenase complex and E3 from
patient were 26 and 2% of controls in blood lymphocytes, and 11 and 14% in
cultured skin fibroblasts, respectively. Western blot analysis demonstrated
that the amount of E3 protein in fibroblasts from the patient and her
father was about half of controls, while Northern blot analysis showed
normal amounts of E3 RNA. DNA sequencing of cloned full-length E3 cDNAs
from the patient revealed two mutations in separate alleles. One is a
single base insertion of an extra adenine in the last codon of the leader
peptide sequence (TAC-->TAAC) leading to a nonsense mutation which
results in the premature termination of the precursor E3 polypeptide
(Y35X). The other is a missense mutation due to substitution of guanine for
adenine, causing an Arg-->Gly substitution at amino acid 460 of the
mature protein (R460G) which triggers the loss of E3 activity probably by
structural change in the E3 dimer. DNA sequencing of E3 cDNAs from the
parents demonstrated that the nonsense mutation was inherited from the
father and the missense mutation was inherited from the mother.
相似文献
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O6-Methylguanine methyltransferase activity is increased in rat tissues by ionising radiation 总被引:3,自引:0,他引:3
The effect of whole body ionising radiation from a linear acceleratoron rat tissue O6-methylguanine (O6-meG) methyl-transferase (MT)activity has been assessed using an assay which measures thetransfer of 3H-radioactivity from 3H-methylated substrate DNAto protein. The maximal effect occurred 2 days after a 1 kraddose, at which time activity in liver extracts was increased5-fold in two different rat strains. Activity in lung and kidneywas increased 4- and 2-fold, respectively. Similar degrees ofenhancement were found in these three tissues using an h.p.l.c.method for measuring MT activity. The increase in activity wasreflected in an increased capacity to repair O6-meG producedin liver DNA by administration of [14C]dimethylnitrosamine (DMN):this effect was dose dependent, being detectable after 30 radsand maximal after 600 rads. Incorporation of labelled breakdownproducts of the DMN into adenine in DNA increased as the doseradiation increased suggesting an inhibition of DNA synthesis.The implications of these results for the mechanism of enhancingO6-meG repair are discussed. 相似文献
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Wendy Chaboyer RN BScHon MN PhD Brigid Gillespie RN B Hlth Sc PhD 《Scandinavian journal of caring sciences》2014,28(4):648-656
Pressure injuries burden patients and healthcare organisations, with some preventative practices having little impact on prevalence reduction. Patient participation in care may be an effective pressure injury prevention strategy, yet patient preferences are unknown. The aim of this interpretive study was to describe patients' perceptions of their current and future role in pressure injury prevention. Semi‐structured interviews were conducted with 20 adult inpatients recruited from four medical units, at two Australian metropolitan hospitals. Interview data were analysed using content analysis, with three categories emerging: ‘experiencing pressure injuries’; ‘participating in pressure injury prevention’; and ‘resourcing pressure injury prevention and treatment’. These categories reflect the complex nature of participants’ pressure injury experience. The findings suggest participants gather pressure injury knowledge from first‐hand and vicarious experience; knowledge they bring to hospital. Most participants preferred a proactive pressure injury prevention role. Many identified barriers in the healthcare environment that impeded their participation and affected their experience of pressure injuries and pressure injury prevention. If patient participation as a pressure injury prevention strategy is to be considered, nurses and organisations need to view patients as partners. 相似文献