Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.3.1.51 (HDR)
 605 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Late renal damage after total body irradiation (TBI) and bone marrow transplantation (BMT) is a recently recognised morbidity. We have tested the effect of single fraction TBI given at two different dose rates on late kidney damage in a mouse model. TBI was given at either high dose rate (HDR; 0.71 Gy/min) or low dose rate (LDR; 0.08 Gy/min). Transplantation with syngeneic marrow cells was done 4-6 h after TBI. Kidney damage was tested using 51CrEDTA residual activity, blood urea nitrogen (BUN) and percentage haematocrit (Hct). TBI alone given at HDR or LDR caused progressive renal damage with no evidence of recovery or plateau. The time latency before the expression of damage was dependent on both dose and the end point used. It was shorter the higher the dose. 51CrEDTA detected renal damage at the same doses as BUN but earlier in time, while %Hct showed evidence of renal damage at doses lower than both BUN and 51CrEDTA. Using the 51CrEDTA the dose-response curves for renal damage were steep and continuously shifting towards lower doses as follow-up time after treatment increased. There was a sparing effect of reducing the dose rate that was more evident at follow-up times of less than a year than at 66 weeks after TBI. Thus, the dose modifying ratio (DMF), defined as the dose needed to cause renal damage in 50% of irradiated animals (ED50) using LDR divided by the ED50 using HDR, was dependent on the time of evaluation.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Renal damage after total body irradiation in a mouse model for bone marrow transplantation: effect of radiation dose rate. 763 Oct 26

A calibration approach was developed to correct for systematic between-cohort dietary measurement errors in the European Prospective Investigation into Cancer and Nutrition (EPIC), a large multicenter cohort study. To validate the 24-h diet recalls (24-HDRs) as reference measurements for between-cohort calibration, we estimated the agreement between center mean nitrogen (N) and total energy intakes and mean 24-h urinary N. Similar analyses using N and energy intake data from different dietary questionnaires (DQs) used at study baseline were conducted to estimate the effect of the calibration approach. This study was conducted between 1995 and 1999, and involved 1103 volunteers of both genders from 12 centers participating in European Prospective Investigation into Cancer and Nutrition. Pearson's correlation coefficients were weighted for study center sample size. When both genders were considered together (n = 22), the correlation coefficients between the center mean log-transformed urinary estimates and the center mean log-transformed dietary N estimates from the 24-HDRs were 0.86 and 0.94 after exclusion of outliers. The corresponding correlation with the DQs was 0.53. When center mean total energy intakes were regressed on center mean urinary N, the correlation remained slightly higher with 24-HDRs (0.91; 0.95 after exclusion of outliers) than DQs (0.86). When stratified by gender, these correlations were systematically higher in men than women with both dietary methods. The beta regression coefficients were not significantly different from 1 when mean N (or total energy intakes) from 24-HDR or DQ were regressed on urinary estimates, except with N from 24-HDRs in men and, in most cases, after adjustment for age, body mass index, and sex with both genders together. This suggests that overall the systematic bias across centers is of uniform magnitude. Although relatively high correlations were observed between urinary N and both dietary methods in men, the errors in DQs tend to vary in both directions (under- and over-reporting) in contrast with 24-HDRs in women. This observation may have implications on the dietary measurement error characteristics and support the potential benefit of between-cohort calibration.
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PMID:Group level validation of protein intakes estimated by 24-hour diet recall and dietary questionnaires against 24-hour urinary nitrogen in the European Prospective Investigation into Cancer and Nutrition (EPIC) calibration study. 1291 11