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31.
The expression of CD59 and other complement regulators was studied in human cerebellum from 14 individuals with no cerebellar pathology, from one patient with multiple sclerosis (MS) and from two patients with paraneoplastic cerebellar degeneration (PCD). CD59 was present on the Purkinje cells at various levels in eight of the 14 cases with no cerebellar pathology. CD59 was also present on the Purkinje cells of the patient with MS, but not on the scarce remaining Purkinje cells of the two patients with PCD. Other complement regulators (CD35, CD46 and CD55) were not expressed on the Purkinje cells, whereas CD59, CD46 and CD55 were present on the molecular, granulosa and endothelial cells. The results suggest that Purkinje cells not expressing CD59 could be especially prone to complement-mediated damage. 相似文献
32.
A monoclonal antibody, HC2.1, has been generated that specifically reacts with both the denatured and the in vitro translated alpha chain of the DR antigen. Although HC2.1 antibody reacted with the alpha chain of protein immunoprecipitated by two DR-specific monoclonal antibodies, L227 and LB3.1, it did not react with the alpha chain of the DQ1 antigen immunoprecipitated by the monoclonal antibody, Genox 3.53. The isoelectric focusing pattern of the alpha chain precipitated by HC2.1 antibody was invariant across a range of DR specificities within a panel of lymphoblastoid cells. The alpha chain of DR antigen from a B cell line was purified by HC2.1-Sepharose immunoaffinity chromatography and limited amino acid sequence analysis was carried out with Staphylococcus aureus SV8 protease fragments purified by high-pressure liquid chromatography. The sequence analysis confirmed that the antigen reactive with HD2.1 antibody is encoded by the DR alpha chain gene. 相似文献
33.
34.
Biomarkers for exposure to ambient air pollution--comparison of carcinogen-DNA adduct levels with other exposure markers and markers for oxidative stress 总被引:5,自引:0,他引:5
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Autrup H Daneshvar B Dragsted LO Gamborg M Hansen M Loft S Okkels H Nielsen F Nielsen PS Raffn E Wallin H Knudsen LE 《Environmental health perspectives》1999,107(3):233-238
Human exposure to genotoxic compounds present in ambient air has been studied using selected biomarkers in nonsmoking Danish bus drivers and postal workers. A large interindividual variation in biomarker levels was observed. Significantly higher levels of bulky carcinogen-DNA adducts (75.42 adducts/10(8) nucleotides) and of 2-amino-apidic semialdehyde (AAS) in plasma proteins (56.7 pmol/mg protein) were observed in bus drivers working in the central part of Copenhagen, Denmark. In contrast, significantly higher levels of AAS in hemoglobin (55.8 pmol/mg protein), malondialdehyde in plasma (0. 96 nmol/ml plasma), and polycyclic aromatic hydrocarbon (PAH)-albumin adduct (3.38 fmol/ microg albumin) were observed in the suburban group. The biomarker levels in postal workers were similar to the levels in suburban bus drivers. In the combined group of bus drivers and postal workers, negative correlations were observed between bulky carcinogen-DNA adduct and PAH-albumin levels (p = 0.005), and between DNA adduct and [gamma]-glutamyl semialdehyde (GGS) in hemoglobin (p = 0.11). Highly significant correlations were found between PAH-albumin adducts and AAS in plasma (p = 0.001) and GGS in hemoglobin (p = 0.001). Significant correlations were also observed between urinary 8-oxo-7, 8-dihydro-2'-deoxyguanosine and AAS in plasma (p = 0.001) and PAH-albumin adducts (p = 0.002). The influence of the glutatione S-transferase (GST) M1 deletion on the correlation between the biomarkers was studied in the combined group. A significant negative correlation was only observed between bulky carcinogen-DNA adducts and PAH-albumin adducts (p = 0.02) and between DNA adduct and urinary mutagenic activity (p = 0.02) in the GSTM1 null group, but not in the workers who were homozygotes or heterozygotes for GSTM1. Our results indicate that some of the selected biomarkers can be used to distinguish between high and low exposure to environmental genotoxins. 相似文献
35.
Summary Kidney growth was investigated in 30-kg pigs after 72 h of unilateral ureteral obstruction. The data were compared to control kidneys from normal non-operated pigs at same weight. Kidney wet weight was determined. Cortex and medulla were separated, and from both regions RNA, DNA, protein and kidney tissue insulin-like growth factor I was determined. Unilateral obstruction caused a doubling of the wet hydronephrotic kidney weight and an ipsilateral 76% increase in total kidney protein content. RNA increased by 45% in the cortex and 76% in the medulla. Kidney protein in the contralateral cortex increased by 23% and RNA by 42%. In the hydronephrotic kidney DNA was reduced by 13% in the cortex and by 21% in the medulla. Contralaterally, DNA was the same as in the controls. Mean kidney insulin-like growth factor I increased sevenfold in the ipsilateral medulla but in the cortex it was the same as in the controls. Serum insulin-like growth factor I concentration was 1.7 ±1.1 g/l in the hydronephrotic animals and 1.2±0.8 g/l in controls. At this stage of obstruction, our data demonstrate (1) hydronephrotic growth that is most probably hyperplastic in the medulla, associated with an increase in medullary insulin-like growth factor I, (2) hyperplastic growth in the cortex, and (3) contralateral kidney growth that is mainly hypertrophic after 72 h of contralateral ureteral obstruction. 相似文献
36.
Effect of short-term hyperventilation on cerebral blood flow autoregulation in patients with acute bacterial meningitis 总被引:2,自引:0,他引:2
Møller K Skinhøj P Knudsen GM Larsen FS 《Stroke; a journal of cerebral circulation》2000,31(5):1116-1122
BACKGROUND AND PURPOSE: Cerebral blood flow (CBF) autoregulation is impaired in patients with acute bacterial meningitis: this may be caused by cerebral arteriolar dilatation. We tested the hypothesis that CBF autoregulation is recovered by acute mechanical hyperventilation in 9 adult patients with acute bacterial meningitis. METHODS: Norepinephrine was infused to increase mean arterial pressure (MAP) 30 mm Hg from baseline. Relative changes in CBF were concomitantly recorded by transcranial Doppler ultrasonography of the middle cerebral artery, measuring mean flow velocity (V(mean)), and by measurement of arterial to jugular oxygen content difference (a-v DO(2)). The slope of the regression line between MAP and V(mean) was calculated. Measurements were performed during normoventilation and repeated after 30 minutes of mechanical hyperventilation. RESULTS: At normoventilation (median PaCO(2) 4.4 kPa, range 3.5 to 4.9), MAP was increased from 68 mm Hg (60 to 101) to 109 mm Hg (95 to 126). V(mean) increased with MAP from 48 cm/s (30 to 61) to 65 cm/s(33 to 86) (P<0.01), and a-v DO(2) decreased from 2.2 mmol/L (1.0 to 2.7) to 1.4 mmol/L (0.8 to 1.8) (P<0.05). During hyperventilation (PaCO(2) 3.5 kPa, range 3.3 to 4.1), MAP was increased from 76 mm Hg (58 to 92) to 109 mm Hg (95 to 121). V(mean) increased from 45 cm/s (29 to 55) to 53 cm/s (33 to 78) (P<0.01), and a-v DO(2) decreased from 2.5 mmol/L (1.8 to 3.0) to 1.8 mmol/L (1.2 to 2.4) (P<0.05). Four patients recovered autoregulation completely during hyperventilation. The slope of the autoregulation curve decreased during hyperventilation compared with normoventilation (P<0.05). CONCLUSIONS: CBF autoregulation is partially recovered during short-term mechanical hyperventilation in patients with acute bacterial meningitis, indicating that cerebral arteriolar dilation in part accounts for the regulatory impairment of CBF in these patients. 相似文献
37.
Høgh P Oturai A Schreiber K Blinkenberg M Jørgensen OS Ryder L Paulson OB Sørensen PS Knudsen GM 《Multiple sclerosis (Houndmills, Basingstoke, England)》2000,6(4):226-230
The purpose of this study was to investigate the relation between APOE genotype and Multiple Sclerosis (MS) in a genetically homogeneous population. We examined 240 patients consulting the MS-clinic during a period of 3 years (1996 - 1999). The mean age of the patients was 41.7 years (range 19 - 80 Y, SD 10.0 Y). As a measure of the progression rate (PR) the last registered Expanded Disability Status Scale (EDSS) score was divided by the time span (years) from disease onset until the latest assessment. The APOE genotype was determined from saliva and/or blood samples using PCR-techniques. The prevalence of different APOE genotypes was compared with the allele-distribution in a population of 361 persons from a Danish cross-sectional population study. The frequency of APOE-epsilon 4/epsilon 4 homozygotes was significantly higher in the MS-group as compared to controls (P<0.05, odds ratio: 2.3), whereas the frequency distribution of other genotypes did not differ significantly. The rate of progression was significantly faster in the APOE-epsilon 4/epsilon 4 homozygotes compared to other genotypes in the MS group (P<0.05). This study suggests that the APOE-epsilon 4/epsilon 4 homozygotes have an increased risk of developing MS. MS patients with the APOE-epsilon 4/epsilon 4 allele may also have an increased rate of disease progression. Multiple Sclerosis (2000) 6 226 - 230 相似文献
38.
Glitsø LV Mazur WM Adlercreutz H Wähälä K Mäkelä T Sandström B Bach Knudsen KE 《The British journal of nutrition》2000,84(4):429-437
To study the intestinal metabolism of lignans, the concentrations of plant and mammalian lignans in intestinal digesta sampled along the intestinal tract of pigs were determined by isotope dilution GC-MS. The pigs were fed rye-bread diets made from either whole rye-grains or rye-grain milling fractions enriched in pericarp-testa, aleurone or endosperm cells. The content and characteristics of dietary fibre varied between diets and had been shown to induce different colon fermentation patterns. As the metabolism of lignans depends on the action of the intestinal flora, we tested whether the rye-bread diets influence the metabolism of lignans. In the ileum, the lignans were mainly present as conjugated plant lignans, which were determined only when the analytical procedure included a hydrolysis step. High recovery of dietary lignans in the ileum may indicate that the lignans enter the enterohepatic circulation. In addition, two to three times the intake of lignans were recovered in the faeces when the diets had a high content of dietary fibre suggesting underestimation of plant lignans in the diet. Most of the plant lignans disappeared from the intestinal tract between the terminal ileum and the caecum. The intestinal concentrations and the disappearance of lignans correlated with the content of lignans in the diet, being highest on the pericarp-testa diet and lowest on the endosperm diet. No effect of fermentation pattern on the intestinal metabolism of lignans was observed. The lignans were liberated from the pericarp-testa diet although the plant cell walls remained largely undegraded. 相似文献
39.
40.
Han JY; Kim HK; Choi BG; Moon H; Hong YS; Lee KS 《Japanese journal of clinical oncology》1998,28(12):749-753
BACKGROUND: Quality of life (QOL) assessment has emerged to measure and
quantify the balance between treatment benefit and toxicity, and has a
value in predicting response and overall survival in cancer patients.
METHODS: From July 1995 to February 1997, 38 symptomatic patients with
advanced non-small cell lung cancer (NSCLC) were treated with MIP
chemotherapy (mitomycin 6 mg/m2, ifosfamide 3000 mg/m2 and cisplatin 50
mg/m2 on day 1 every 3 weeks). Patients were assessed for QOL including
physical well-being, general symptoms and lung cancer-specific symptoms, as
well as objective response. RESULTS: The overall response rate was 38.9%
(14/36, all were partial response) and the median duration of response was
3.5 months [95% confidence interval (CI) 2.0-4.0]. The median duration of
overall survival was 7 months (95% CI 5.9-8.5). The overall improvement of
QOL was 58.3% with 21 patients feeling better on treatment. The toxicity of
chemotherapy was mild, mainly nausea/vomiting and minimal alopecia. Using
multiple clinical predictors of survival (age, histology, stage,
performance status), only change of QOL emerged significantly (P = 0.0007).
CONCLUSIONS: MIP had an endurable response and low toxicity profile, and
provided good QOL. Integral QOL data in our study provided the strong
prediction of survival in advanced NSCLC. Further experienced QOL study
will provide greatly enhanced outcome data in clinical trials.
相似文献