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Progestogens of varying androgenicity and cardiovascular risk factors in postmenopausal women receiving oestrogen replacement therapy 总被引:3,自引:0,他引:3
Kwok S Selby PL McElduff P Laing I Mackness B Mackness MI Prais H Morgan J Yates AP Durrington PN Sci FM 《Clinical endocrinology》2004,61(6):760-767
OBJECTIVE: Medroxyprogesterone (MP) was used as the progestogen in randomized clinical trials of postmenopausal hormone replacement on cardiovascular risk. To attempt to understand the lack of benefit in these trials, we have examined the effects of MP and two other progestogens, the less androgenic desogestrel (DG) and the more androgenic norethisterone (NE), on cardiovascular risk factors against a background of oestrogen therapy. DESIGN AND MEASUREMENTS: Thirty-four women were treated with conjugated equine oestrogens (CEE) 0.625 mg daily alone for 12 weeks, followed in random order by each of the three progestogens (DG 75 microg, MP 10 mg and NE 1 mg daily) given sequentially for three 12-week cycles while maintaining the same CEE treatment. We measured serum lipoproteins, paraoxonase activity, C-reactive protein (CRP), fibrinogen, fasting glucose and insulin levels at baseline, at the end of the oestrogen-only phase and at the end of each of the combined oestrogen and progestogen phases. RESULTS: The addition of progestogens to CEE maintained the oestrogen-induced reduction in apolipoprotein B (apo B) and lipoprotein (a) [Lp(a)], and further lowered total cholesterol (P < 0.01) and fibrinogen (P < 0.001). CEE raised serum triglyceride (P < 0.001) and CRP (P < 0.01) concentrations, which reverted towards pre-oestrogen levels with progestogens. Progestogens significantly reduced high density lipoprotein (HDL) cholesterol (P < 0.05). NE was associated with the greatest reduction in HDL cholesterol and apo A1, but was most effective in preserving paraoxonase activity and reducing the potentially unfavourable oestrogen-induced increases in triglycerides and CRP. CONCLUSION: Preconceptions that more androgenic progestogens necessarily have more unfavourable effects on cardiovascular risk factors may require revision. 相似文献
98.
Chang KC Leung CC Yew WW Ho SC Tam CM 《American journal of respiratory and critical care medicine》2004,170(10):1124-1130
This nested case-control study aimed at evaluating treatment-related risk factors of relapse of tuberculosis under a service program of directly observed treatment. Out of 12,183 patients with pulmonary tuberculosis who completed treatment within 1 year, 113 relapsed within 30 months after commencement of therapy. The overall 30-month relapse rate was 0.9% (95% confidence interval [CI] 0.8-1.1%). On matching 113 cases with 226 control subjects in a conditional logistic model, thrice-weekly treatment increased the risk of relapse in comparison with daily treatment (odds ratio 3.92, 95% CI 1.78-8.63), whereas prolonging both intensive phase and overall treatment by 50% or more protected against relapse (odds ratio 0.24, 95% CI 0.08-0.70). When pretreatment culture was positive and cavitation was absent, the 30-month relapse rate for standard thrice-weekly regimen was 1.1% (95% CI 0.6-2.0%). The corresponding rates in the presence of cavitation were 7.8% (95% CI 4.0-14.6%) for standard thrice-weekly regimen; 3.3% (95% CI 1.9-5.5%) for standard daily regimen; 0.5% (95% CI 0.1-2.6%) for extended thrice-weekly regimen; and 0.4% (95% CI 0.1-0.9%) for extended daily regimen. Further studies are required to reduce the risk of relapse under program settings. 相似文献
99.
Human burst-forming units-erythroid need direct interaction with stem cell factor for further development 总被引:6,自引:3,他引:6
To understand the factors that regulate the early growth and development of immature erythroid progenitor cells, the burst-forming units-erythroid (BFU-E), it is necessary to have both highly purified target cells and a medium free of serum. When highly purified human blood BFU-E were cultured in a serum-free medium adequate for the growth of later erythroid progenitors, BFU-E would not grow even with the addition of recombinant human interleukin-3 (rIL-3), known to be essential for these cells. However, the addition of recombinant human stem cell factor (rSCF), which supports germ cell and pluripotential stem cell growth, stimulated BFU-E to grow equally well in serum-free as in serum-containing medium. Limiting dilution studies showed that rSCF acts directly on the BFU-E that do not require accessory cells for growth. Furthermore, rSCF was necessary for BFU-E development during the initial 7 days of culture, until these cells reached the stage of the late progenitors, the colony-forming units-erythroid (CFU-E). These studies indicate that early erythropoiesis is dependent on the direct action of SCF that not only affects early stem cells but is continually necessary for the further development of committed erythroid progenitor cells until the CFU-E stage of maturation. 相似文献
100.
Molassiotis Alex Kwok Stephen W. H. Leung Angela Y. M. Tyrovolas Stefanos 《Age (Dordrecht, Netherlands)》2022,44(2):925-951
GeroScience - The needs of the aging populations are putting increasing burden on healthcare particularly in the Western Pacific Region (WPR), which is the home of aging economies such as Hong Kong... 相似文献