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91.
L. A. P. Hoogenboom J. Tulliez J. -P. Gautier R. D. Coker J. -P. Melcion M. J. Nagler Th. H. G. Polman J. Delort-Laval 《Food Additives & Contaminants》2001,18(1):47-58
Peanut meal naturally contaminated with 3.5mg/kg aflatoxin B1 (AFB1) was spiked with radiolabelled AFB1 (meal14C-I0) and decontaminated by a smallscale copy of an industrial ammoniation process (meal 14C-I1). During the process 15% of the radioactivity was lost, whereas 90% of the remaining radiolabel could not be extracted from the meal. In the extractable part, AFB1 accounted for 10% of the radiolabel, consistent with a total AFB1 reduction of more than 99%. No degradation products were observed in the extracts. Four lactating cows were fed with a diet containing 15% of either meal 14C-I0 or 14C-I1 for 10 days. On day 9 of this treatment, respectively 23 and 67% of the radiolabel was excreted in the urine and faeces of cows fed meal 14C-I0, as compared with 2 and 101% in the case of cows fed meal 14C-I1. Milk contained respectively 1.35 (meal 14C-I0) and 0.25% (meal 14C-I1) of the radiolabel. Milk samples taken during the equilibrium stage contained respectively 5 and 0.5 ng/ml of AFB1-derived compounds. Aflatoxin M1 (AFM1) accounted for 50-80% of these compounds in the case of milk from cows fed 14C-I0, as compared with 6-20% in the case of 14C-I1. AFB1 to AFM1 carry-over rates for 14C-I0 or 14 相似文献
92.
93.
CD Day NJ Smilinich GV Fitzpatrick PJ deJong TB Shows MJ Higgins 《Canadian Metallurgical Quarterly》1999,10(2):182-185
BACKGROUND: Right lower quadrant abdominal pain may pose a diagnostic problem in patients with cystic fibrosis. Abdominal ultrasound examination, used commonly in the diagnostic work-up, may reveal abnormalities of the appendix. However, interpretation of such findings is problematic, because the appearance of the gastrointestinal system during routine examination has not been documented in patients with cystic fibrosis. The purpose of this study was to investigate the findings during routine abdominal ultrasound scans in our cohort of patients with cystic fibrosis and in control subjects. METHODS: Abdominal ultrasound scans were performed prospectively during routine clinic visits in a cohort of patients with cystic fibrosis. RESULTS: Fifty patients aged 10+/-6 years, (range, 0.5-28 years) were examined; 45 had pancreatic insufficiency. Four patients (3 with pancreatic insufficiency) reported right lower quadrant pain at the time of the scan. According to standard ultrasound criteria, the appearance of the appendix was abnormal in 8 patients (16%), 6 had a mucoid appendix, and 2 had a pathologically thickened appendiceal wall. Only 1 of these 8 patients mentioned abdominal pain at the time of the study. Other incidental findings included gallstones (3 patients), intussusception (2 patients), and pancreatic cyst (1 patient). CONCLUSIONS: Abnormalities can be observed during routine abdominal ultrasonographic studies in cystic fibrosis. These findings may not be associated with abdominal pain; their clinical relevance needs further investigation. 相似文献
94.
95.
L Gao L Liu D van Meyel G Cairncross P Forsyth D Kimmel RB Jenkins NJ Lassam D Hogg 《Canadian Metallurgical Quarterly》1997,3(6):977-981
Gliomas are tumors of the central nervous system that may be inherited in some patients. The gene(s) responsible for the clustering of gliomas in families have not yet been identified. Molecular studies of sporadic high-grade gliomas have revealed mutations or deletions of the genes encoding the protein kinase inhibitors p16(INK4A) and p15(INK4B) in a large proportion of tumors. Moreover, those tumors without deletions frequently display gene amplification and/or over-expression of mRNA encoding the protein kinase cdk4. We hypothesized that germ-line mutations in the p16(INK4A), p15(INK4B), or CDK4 genes might contribute to some cases of familial gliomas. To address this issue, we analyzed 36 kindreds with a predisposition to glial tumors. Genomic DNA from index members of these families was screened by PCR-single-strand conformational polymorphism analysis. We did not detect any functional mutations in the p16(INK4A), p15(INK4B), or CDK4 genes, although two individuals did have a previously described A140T polymorphism in p16(INK4A). Thus, despite the association between the sporadic forms of high-grade glioma and abnormalities of p16(INK4A), p15(INK4B), or CDK4, we found no evidence that germ-line mutations in the coding region of these three genes predispose to inherited glial tumors. 相似文献
96.
97.
L Lyras NJ Cairns A Jenner P Jenner B Halliwell 《Canadian Metallurgical Quarterly》1997,68(5):2061-2069
Oxidative stress may contribute to neuronal loss in Alzheimer's disease (AD). The present study compares the levels of oxidative damage to proteins, lipids, and DNA bases from seven different brain areas of AD and matched control tissues by using a range of techniques. No differences in levels of lipid peroxidation were found in any of the brain regions by using two different assay systems. Overall, there was a trend for protein carbonyl levels to be increased in AD in frontal, occipital, parietal, and temporal lobe, middle temporal gyrus, and hippocampus, but a significant difference was found only in the parietal lobe. Gas chromatography-mass spectrometry was used to measure products of damage to all four DNA bases. Increased levels of some (8-hydroxyadenine, 8-hydroxyguanine, thymine glycol, Fapy-guanine, 5-hydroxyuracil, and Fapy-adenine), but not all, oxidized DNA bases were observed in parietal, temporal, occipital, and frontal lobe, superior temporal gyrus, and hippocampus. The baseline level of oxidative DNA damage in the temporal lobe was higher than in other brain regions in both control and AD brain. The finding of increased oxidative damage to protein and DNA strengthens the possibility that oxidative damage may play a role in the pathogenesis of AD in at least some key brain regions. 相似文献
98.
HS Matloub WW Dzwierzynski S Erickson JR Sanger NJ Yousif V Muoneke 《Canadian Metallurgical Quarterly》1996,21(3):451-455
This study was undertaken to determine the usefulness of magnetic resonance imaging (MRI) in the diagnosis of flexor tendon rupture in patients who had prior surgery. Magnetic resonance imaging scans were performed on 11 digits (16 tendons) with the clinical diagnosis of flexor tendon rupture. Clinical suspicion correlated with MRI and surgical findings. Clinical examination yielded a 60% accuracy in diagnosis. MRI differentiated rupture from adhesions with a 100% accuracy rate. The MRI scan is a valuable tool in diagnosing tendon ruptures and may help reduce the incidence of unnecessary tendon explorations. 相似文献
99.
100.
NJ Meropol M Porter LE Blumenson MJ Lindemann RP Perez L Vaickus GM Loewen PJ Creaven KA Wilkes MA Giedlin MA Caligiuri 《Canadian Metallurgical Quarterly》1996,2(4):669-677
We aimed to determine the toxicity and immunological effects of daily s.c. administered low-dose interleukin (IL) 2. Adult cancer patients received a single daily s.c. injection of IL-2 as outpatients for 90 consecutive days. Cohorts of four to nine patients were treated at escalating IL-2 dose levels until the maximum tolerated dose (MTD) was defined. Peripheral blood mononuclear cell phenotyping, IL-2 serum levels, and the presence of anti-IL-2 antibodies were investigated. Thirty-eight patients were treated at seven IL-2 dose levels ranging from 0.4 to 1.75 million International Units (mIU)/m2 daily. The MTD was 1.25 mIU/m2, with constitutional side effects, vomiting, and hyperglycemia dose limiting. Severe toxicity did not occur at or below the MTD, although mild local skin reaction and mild constitutional side effects were common. Objective tumor regressions were not observed during this Phase I trial. Low-dose IL-2 resulted in natural killer (NK) cell (CD3(-) CD56(+)) expansion at all dose levels. This effect was dose dependent (P < 0.01), ranging from a 154 to 530% increase over baseline. Peak NK levels were achieved at 6-8 weeks and sustained through 12 weeks of therapy. As predicted by in vitro studies of IL-2 receptor structure-activity relationships, the subset of NK cells that constitutively express high-affinity IL-2 receptors (CD3(-)CD56(bright+)) showed more profound dose-dependent expansion, with increases ranging from 368 to 2763% (P = 0.015). NK expansion occurred at peak IL-2 levels <10 pM (2.3 IU/ml). Three patients developed nonneutralizing anti-IL-2 antibodies. Thus, we concluded that selective expansion of NK cells may be achieved in vivo with daily s.c. injections of low-dose IL-2 with minimal toxicity. 相似文献