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961.
OBJECTIVE: To investigate the correlation between soluble forms of the intercellular adhesion molecule (sICAM-1) and vascular cell adhesion molecule (sVCAM-1) and the severity of pre-eclampsia or its possible consequences for fetal growth. DESIGN: Prospective observational study. SETTING: Institute of Medical Genetics, University of Oslo, Department of Medical Genetics and Haematological Research Laboratory, Ullev?l University Hospital; and the Department of Obstetrics and Gynaecology, The National Hospital, Oslo, Norway. PARTICIPANTS: Seventy-six women with normotensive pregnancies and 157 women with pre-eclampsia divided into three subgroups: mild, severe and pre-eclampsia with fetal growth retardation. METHODS: ELISA-measurements of plasma sICAM-1 and sVCAM-1 were performed in a group of healthy pregnant normotensive women and three groups of women with varying degrees of pre-eclampsia. RESULTS: sICAM-1 concentrations were higher in the pre-eclampsia group compared with the control group, but this difference was not statistically significant. Plasma concentrations of sVCAM-1 were significantly greater (P < 0.0001) in all pre-eclampsia subgroups (835.34, 855.25 and 964.05 ng/mL) compared with the control group (667.62 ng/mL). Within the pre-eclampsia group, plasma concentration of sVCAM-1 was significantly higher in the subgroup exhibiting fetal growth retardation (P = 0.03) compared with mild pre-eclampsia. CONCLUSION: The observed increases in plasma concentrations of sVCAM-1 suggest that measurements of this adhesion molecule may be useful in monitoring pregnancies with respect to the development of pre-eclampsia or fetal growth retardation. 相似文献
962.
963.
964.
A panel of four monoclonal antibodies produced in our laboratory, MIL1, MIL2, MIL3, MIL4, and the type-specific monocyte/granulocyte marker 74-22-15 were used to isolate and to discriminate between monocytes, macrophages and granulocytes derived from porcine peripheral blood, lung and gut lamina propria. Two-colour flow cytometry and cell sorting showed that while no monoclonal antibody was specific for just a single cell population, each cell type had a unique and characteristic combination of surface antigens. These differences could be used to identify and purify monocytes, macrophages, neutrophils, eosinophils and basophils from the three different sites. The study also demonstrated similarities and differences within cell types from the same site and from different sites: polymorphonuclear neutrophils (PMN) from peripheral blood were subdivided into two subpopulations by the presence or absence of the surface antigen recognized by MIL4, while PMN from alveolar lavage did not express this antigen. Peripheral blood eosinophils were also divided into subpopulations by the presence or absence of the same surface antigen. Lamina propria eosinophils strongly expressed the MIL4 marker and differed morphologically from blood eosinophils. Peripheral blood basophils and lamina propria mast cells were morphologically similar and expressed similar antigens. Monocytes and alveolar macrophages also expressed the same surface antigens. 相似文献
965.
IA Antonijevic H Murck RM Frieboes R Horn G Brabant A Steiger 《Canadian Metallurgical Quarterly》1998,32(6):403-410
Leptin, the protein product of the obese (ob) gene, has been suggested to play a role in the regulation of food intake. As depressive episodes are frequently characterized by loss of appetite, reduced food intake and weight loss, altered leptin secretion might also be expected in patients with depression. Therefore, we examined nocturnal (10.00 p.m. to 7.00 a.m.) secretion of leptin, cortisol, ACTH and growth hormone (GH) in a group of 15 patients with depression and age- and sex-matched controls (age range 23-71 years). In addition, the effects of pulsatile administration of growth hormone-releasing hormone (GHRH), thought to be an endogenous antagonist of corticotropin-releasing hormone (CRH), which in turn is believed to play a critical role for the pathophysiology of depression, on nocturnal hormone secretion were assessed. Patients with depression showed a trend towards elevated nocturnal cortisol secretion (F = 3.8, p < 0.05). Nocturnal serum leptin was significantly higher in patients, despite a reported weight loss (F = 8, p < 0.05), but showed the same sexual dimorphism as in controls (F = 20.9, p < 0.01). No significant differences were seen between patients and controls with regard to plasma GH and ACTH. GHRH treatment increased GH secretion in both patients and controls, while the other hormones were not affected. Furthermore, serum leptin was correlated with body mass index (BMI) in controls, but not in patients with depression, supporting an altered regulation of leptin secretion in depressive illness. Finally, we provide some evidence that in young female patients the normal nocturnal leptin surge is blunted. As glucocorticoids can prevent the fasting-induced decline in serum leptin, we propose that hypercortisolism in depression might counteract the reduction in leptin secretion caused by decreased food intake and weight loss. Elevated serum leptin in depression might in turn further promote CRH release, as shown in animals and, hence, contribute to HPA system hyperactivity seen in depression. 相似文献
966.
RM Calvo JM Roda MJ Obregón G Morreale de Escobar 《Canadian Metallurgical Quarterly》1998,801(1-2):150-157
We have studied T4 and T3 concentrations, DNA and protein concentrations and 5' and 5 deiodinases in samples of brain tumors obtained at surgery from 49 patients, and, in most cases, also from surrounding normal tissue. T4 concentrations in normal cortical tissue (6.19+/-0.45 ng/g) were lower than in white matter, but the difference disappeared when referred to the DNA content (2.26+/-0.27 ng/mg DNA). No other differences were found between cortical and white matter, or among cortical lobes. T4 in normal tissue was higher than previously reported, mostly from autopsy samples, whereas T3 (0.99+/-0.07 ng/g) was similar. 5'D-I activity was negligible as compared to 5'D-II (8.11+/-1.09 fmol/h/mg protein). When expressed in relation to the different DNA contents of normal vs. tumoral tissue, 5'D-II activities were the same for both. 5D activity was highly variable in the tumoral tissue, with negligible activities in meningiomas and pituitary adenomas. When referred to the DNA content, T4 and 5'D-II were the same, but T3 concentrations were lower in the tumor (0.24+/-0.03 ng/mg DNA) as compared to normal (0.35+/-0.04 ng/mg DNA) tissue samples. Whether or not this decrease of T3 affects the expression of T3-sensitive processes remains to be studied. 相似文献
967.
968.
RM Heller 《Canadian Metallurgical Quarterly》1994,1(2):201-204
Germinating conidiospores (conidia) of Aspergillus nidulans amino acid-requiring strains are hypersensitive to heat, oxidative stress, UV radiation and chemical mutagens when compared with other strains. They also showed an increased mutation rate. Sensitivity to stress conditions has been correlated with an abnormal RAS/cAMP pathway in mutants of S. cerevisiae. We suggest that the RAS/cAMP pathway is defective in germinating conidia of Aspergillus amino acid auxotrophs and that this is responsible for suppressing DNA repair and conferring sensitivity to oxidative stress and heat shock. 相似文献
969.
970.
RM MacKie D Hole JA Hunter R Rankin A Evans K McLaren M Fallowfield A Hutcheon A Morris 《Canadian Metallurgical Quarterly》1997,315(7116):1117-1121
OBJECTIVE: To determine the changing incidence of and mortality from cutaneous malignant melanoma in Scotland from 1979 to 1994. DESIGN: Detailed registration of clinical and pathological features, surgical and other treatment, and follow up of all cases of cutaneous malignant melanoma diagnosed from 1979 to 1994 and registered with specialist database for Scotland. SETTING: Scotland. SUBJECTS: 6288 patients with invasive primary cutaneous malignant melanoma diagnosed between 1 January 1979 and 31 December 1994. RESULTS: The annual age standardised incidence of cutaneous malignant melanoma rose significantly from 3.5 to 7.8 per 100,000 per year in men and from 6.8 to 12.3 per 100,000 per year in women (P < 0.001 for both). World standardised rates increased from 2.7 to 6.0 per 100,000 per year in men and 4.6 to 8.50 per 100,000 in women. The incidence of melanoma continued to increase significantly in men of all ages during the study, but the rate stabilised in women after 1986. Mortality from cutaneous malignant melanoma was 1.3 per million per annum in men in 1979, rising to 2.3 per million per annum in 1994 (P < 0.01); it was 2.4 per million per annum in women in 1979, falling to 1.9 per million per annum in 1994 (P = 0.09). The underlying mortality trends showed a continuing rise for men but a downward trend for women that was not significant (P = 0.09). In men, melanoma free survival was 69% at 5 years and 61% at 10 years; in women the corresponding rates were 82% and 75%. Younger patients had higher survival rates, which were not entirely explained by thinner tumours. Over the 15 year period, survival rates improved by 12% overall, only partly owing to thinner tumours. CONCLUSIONS: In Scotland the incidence of melanoma in women has stabilised, while mortality associated with melanoma in women shows a downward trend. 相似文献