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1.
Third-generation oral contraceptives (OC) have been associated with an increased risk of venous thrombosis compared with second-generation OC. To find an explanation for this increased risk, the effect of a second- and third-generation OC and of the progestagens used in these pills on several fibrinolytic parameters was studied in the absence or presence of the factor V Leiden mutation. In a single-center, double-blind trial, 51 women without and 35 women with the factor V Leiden mutation were randomized to either a second-generation (30 microg ethinylestradiol/150 microg levonorgestrel) or a third-generation (30 microg ethinylestradiol/150 microg desogestrel) oral contraceptive. After two menstrual cycles of use and a wash-out period of two cycles, the participants received the corresponding progestagen-only preparation containing 150 microg levonorgestrel or 150 microg desogestrel. D-Dimers, thrombin-activatable fibrinolysis inhibitor (TAFI) and the clot lysis time in the absence (LYSmin) or the presence (LYSplus) of a blocking anti-factor XI antibody were determined in plasmas of the participating women, and the mean difference in changes between the OC were calculated. Both combined OC induced increased plasma levels of D-dimers and TAFI, and induced a prolongation of LYSplus, whereas LYSmin hardly changed. Virtually no changes in fibrinolytic parameters were observed for the progestagen-only preparations. No differential effects between levonorgestrel- and desogestrel-containing OC were found in women without factor V Leiden. Women with the mutation on levonorgestrel-containing OC showed an increased LYSplus compared with desogestrel containing OC (3.9; 95% confidence interval, 0.1-7.7). When using progestagen-only preparations, no differential effect on the fibrinolytic parameters were found, except for non-carriers on levonorgestrel who showed a reduced LYSmin compared with non-carriers on desogestrel (-4.0; 95% confidence interval, -7.8 to -0.2). In conclusion, the effect of oral contraceptives on fibrinolytic parameters is largely independent of the type of progestagen. The increased fibrinolytic activity during OC use appears to be induced by the estrogen component and may be counteracted by increased TAFI activation. This may result in an enhanced downregulation of fibrinolysis.  相似文献   

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Epidemiological studies have shown that women who use third-generation oral contraceptives (OC) containing desogestrel, gestodene or norgestimate have a higher risk of venous thrombosis than women who use second-generation OC containing levonorgestrel. It is also known that a mutation in factor V (factor VLeiden), which results in resistance to activated protein C (APC) and which is the most common cause of hereditary thrombophilia, potentiates the prothrombotic effect of OC.
Effects of APC on thrombin generation in the plasma of women using OC were compared to the response to APC in non-OC users and in individuals that were hetero-zygous or homozygous for factor VLeiden. The response towards APC was evaluated on basis of the ratio (APC-sr) of the time integrals of thrombin formation determined in the presence and absence of APC.
Compared with women not using OC, women who used OC exhibited a significantly decreased sensitivity to APC ( P  < 0.001), independent of the kind of OC used. Women who used third-generation monophasic OC were significantly less sensitive to APC than women using second-generation OC ( P  < 0.001) and had APC-sr that did not significantly differ from heterozygous female carriers of factor VLeiden who did not use OC. Women who were heterozygous for factor VLeiden and used OC had APC-sr in the range of homozygous carriers of factor VLeiden. Two women who started OC therapy had significantly elevated APC-sr within 3 d.
Acquired APC resistance may explain the epidemiol-ogical observation of increased risk for venous thrombosis in OC users, especially in women using third-generation OC.  相似文献   

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OBJECTIVES: The effect of a second and third generation oral contraceptive and of the progestagens used in these pills on lipid metabolism was studied in the absence or presence of the factor V Leiden mutation. DESIGN: A single centre, double blind randomized trial. SETTING: University Medical Centre. SUBJECTS: A total of 51 women without and 35 women with the factor V Leiden mutation. INTERVENTIONS: A second generation (30 microg ethinylestradiol/150 microg levonorgestrel) or a third generation (30 microg ethinylestradiol/l 50 microg desogestrel) oral contraceptive. After two cycles of use and a wash-out period of two cycles, the participants received the corresponding progestagen-only preparation containing 150 microg levonorgestrel or 150 microg desogestrel. MAIN OUTCOME MEASURES: Mean difference in changes between the treatment groups on total cholesterol, HDL, LDL, triglycerides and total/HDL cholesterol ratio. RESULTS: Compared with levonorgestrel, desogestrel-containing oral contraceptives caused in women without the factor V Leiden mutation significant changes in HDL (0.43; 95% confidence interval [CI] 0.25-0.61), LDL (-0.55; 95% CI -0.90 to -0.20), triglycerides (0.19; 95% CI 0.06-0.32) and total/ HDL cholesterol ratio (-0.87; 95% CI -1.21 to -0.53). When the progestagen-only preparations were used, differential changes were found for HDL (0.16; 95% CI 0.03-0.29), LDL (-0.31; 95% CI - 0.56 to -0.05) and total/HDL cholesterol ratio (-0.55; 95% CI -0.84 to -0.26). Desogestrel-only caused changes opposite to those of desogestrel-containing oral contraceptives. For cholesterol and triglycerides, this effect was also found for levonorgestrel-only in comparison with levonorgestrel-combined oral contraceptives. Levonorgestrel appeared to induce the effect on HDL. Almost all results were similar for women with the factor V Leiden mutation. CONCLUSION: It appears that desogestrel counteracts the effects of oestrogens to a lesser extent than levonorgestrel. Desogestrel-containing oral contraceptives have therefore a more favourable influence on cholesterol metabolism in comparison with levonorgestrel-containing oral contraceptives.  相似文献   

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Estrogen replacement therapy (ERT), which produces acquired resistance to activated protein C when superimposed on heritable resistance to activated protein C (the mutant Factor V Leiden trait), may promote venous and arterial thrombosis. In a cross-sectional study of 423 women referred for hyperlipidemic therapy (93 of whom [22%] were on ERT), our specific aim was to determine whether ERT and heterozygosity for the Factor V Leiden mutation and/or resistance to activated protein C interacted as risk factors for atherothrombosis. Of the 423 women, 168 (40%) had atherothrombosis, 19 (4%) were heterozygous for Factor V Leiden mutation or had resistance to activated protein C <2 (Factor V Leiden mutation+), and 404 were wild-type normal for the Factor V gene and/or had resistance to activated protein C > or =2 (Factor V Leiden mutation-). By stepwise logistic regression, positive explanatory variables for atherothrombosis included hypertension (p = 0.002), age (p = 0.003), relatives with atherothrombosis (p = 0.002), anticardiolipin antibody immunoglobulin-M (p = 0.02), and a Factor V Leiden mutation*ERT interaction term where atherothrombosis events were more likely in 2 subgroups of women (ERT- and Factor V Leiden mutation-) or (ERT+ and Factor V Leiden mutation+) (p = 0.02). High-density lipoprotein cholesterol was inversely associated with atherothrombosis (p = 0.004). In a separate logistic regression model for the 213 women with a polymerase chain reaction measurement of the Factor V gene, ERT was protective (p = 0.008); the Factor V Leiden mutation was positively associated with atherothrombosis (p = 0.05). The atherothrombosis odds ratio risk for ERT (yes vs no) was 0.36 (95% confidence intervals [CI] 0.16 to 0.74, p = 0.007). The atherothrombosis risk odds ratio in women heterozygous for the Factor V Leiden mutation (vs normal) was 2.00 (95% CI 1.02 to 4.22, p = 0.05). ERT may be protective against atherothrombosis when the Factor V Leiden mutation is absent, whereas the Factor V Leiden mutation may increase risk for atherothrombosis, particularly in the presence of ERT. We suggest that the Factor V Leiden mutation be measured in all women on ERT or before beginning ERT to identify those heterozygous for the Factor V Leiden mutation (4%), in whom ERT is relatively or absolutely contraindicated because of increased risk for atherothrombosis and thromboembolism. A second, much larger group of women will also be identified without the factor V Leiden mutation (96%), in whom ERT may reduce the risk for atherothrombosis.  相似文献   

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This cycle-controlled randomized cross-over study examined the effects of a second-generation oral contraceptive (OC) containing levonorgestrel and a third-generation OC containing desogestrel on the anticoagulant action of activated protein C (APC) in the plasma. The response to APC in plasma was assessed in 28 women who received two consecutive cycles of a second-generation OC (150 mcg levonorgestrel and 30 mcg ethinyl estradiol) or a third-generation OC (150 mcg desogestrel and 30 mcg ethinyl estradiol), and who switched preparations after two pill-free cycles. Normalized APC sensitivity ratio was also taken from these women. Results showed that in the 28 women the normalized APC sensitivity ratio increased during treatment with both preparations. Compared with levonorgestrel, desogestrel-containing OC treatment caused a highly significant (p 0.0001) additional increase in normalized APC sensitivity ratio (0.51; 95% CI, 0.37-0.66). In conclusion, OC treatment diminishes the efficacy with which APC down-regulates in-vitro thrombin formation.  相似文献   

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We present the case history of a 22-yr-old woman diagnosed with ischemic colitis associated with the use of oral contraceptives (OC). At the time of her presenting symptoms activated protein C (APC) resistance, a risk factor for thrombosis, was demonstrated. There was no laboratory evidence of inherited thrombophilia; that is, antithrombin III, protein C and protein S levels were normal and the factor V Leiden mutation was not present. The OC were discontinued and the patient's symptoms improved. Subsequent evaluation revealed that the activated protein C resistance had resolved. This case illustrates APC resistance as a potential link between OC use and its known association with ischemic colitis.  相似文献   

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Resistance to the anticoagulant effect of activated protein C (APC resistance), a frequent abnormality in patients with a history of venous thrombosis, is known to be due, in the large majority of cases, to the presence of an abnormal factor V: the factor V Leiden. It is reasonable to surmise that screening for this abnormality should be performed with a clotting method for APC resistance, before submitting the patients with abnormal results to DNA analysis. The present study was performed on 216 individuals enrolled at the Bologna centre, of which 189 were unrelated patients with a history of juvenile venous thromboembolism and 27 were relatives with or without thrombosis. APC resistance was first measured in Bologna by a standard commercial method and then, in Leiden, by an in-house method; DNA analysis was performed in those cases in which at least one of the clotting methods was abnormal. The data obtained confirm the good performance and the optimal positive predictive value for the Leiden mutation (100%) of the Leiden in-house clotting method. Performance of the commercial method was less satisfactory but markedly improved by expressing the data in relation to the values simultaneously obtained with a normal plasma pool. Even with optimal data expression, however, the positive predictive value of the commercial method, versus DNA analysis, did not exceed 88%.
It is concluded that further standardization of the commercial method here evaluated is necessary before it can be widely adopted for the screening of APC resistance and prediction of the presence of factor V Leiden.  相似文献   

13.
Oral contraceptives (OC) modulate the risk for developing cardiovascular (CV) diseases. The aim of this study was to determine whether the use of third-generation OC has an impact on markers of CV disease in genetically identical women. We performed an intrapair comparison in 27 monozygotic twin pairs, one of whom was taking third-generation OC, whereas the other was not using OC. Biometric parameters were ascertained and conventional and 24-h ambulatory blood pressure (BP) was recorded. A fasting blood sample was taken for the measurement of glucose, insulin, proinsulin, lipids, and insulin-like growth factor binding protein-1 (IGFBP-1). Insulin resistance and beta-cell function were calculated by homeostasis model assessment (HOMA). A 24-h urine sample for cortisol was obtained. Third-generation OC use increased 24-h ambulatory systolic and diastolic BP by 5.2 and 3.9 mmHg, respectively (both P=0.0003). There was no effect on glucose, insulin and proinsulin levels, and on HOMA parameters, but the IGFBP-1 levels were markedly raised (P=0.0009). The lipid profile showed a 34% increase in triglyceride levels (P < 0.0001), but also a 7% increase in HDL-cholesterol levels (P=0.037). Use of third-generation OC impacts on CV disease markers in young-adult genetically identical women. Some changes are beneficial (increased HDL-cholesterol), whereas others may be deleterious (increased BP and triglyceride levels) or have unknown effects at this time (increased IGFBP-1 levels).  相似文献   

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-Postmenopausal hormone replacement therapy (HRT) is associated with low cardiovascular morbidity and mortality in epidemiological studies. Yet, no randomized trial has examined whether HRT is effective for prevention of coronary heart disease (CHD) in women with increased risk. The objective of this study was to determine whether HRT can slow progression of atherosclerosis, measured as intima-media thickness (IMT) in carotid arteries. Carotid IMT is an appropriate intermediate end point to investigate clinically relevant effects on atherogenesis. This randomized, controlled, observer-blind, clinical, single-center trial enrolled 321 healthy postmenopausal women with increased IMT in >/=1 segment of the carotid arteries. For a period of 48 weeks, subjects received either 1 mg/d 17ss-estradiol continuously plus 0.025 mg gestodene for 12 days every month (standard-progestin group), or 1 mg 17ss-estradiol plus 0.025 mg gestodene for 12 days every third month (low-progestin group), or no HRT. Maximum IMT in 6 carotid artery segments (common, bifurcation, and internal, both sides) was measured by B-mode ultrasound before and after intervention. HRT did not slow IMT progression in carotid arteries. Mean maximum IMT in the carotid arteries increased by 0.02+/-0.05 mm in the no HRT group and by 0.03+/-0.05 and 0.03+/-0.05 mm, respectively, in the HRT groups (P:>0.2). HRT significantly decreased LDL cholesterol, fibrinogen, and follicle-stimulating hormone. In conclusion, 1 year of HRT was not effective in slowing progression of subclinical atherosclerosis in postmenopausal women at increased risk.  相似文献   

17.
Serum from 91 patients with Sj?gren's syndrome (SS) was examined for antiperinuclear factor (APF). Nine out of 29 patients with SS alone (31.0%) were positive as opposed to 27 out of 40 with SS + rheumatoid arthritis (67.5%) and to 3 out of 22 with SS + other autoimmune disorders (13.6%). A clear relationship was established between APF and agglutinating or non-agglutinating rheumatoid factor.  相似文献   

18.
Summary. The effects of the cytotoxic drugs, adriamycin, cyclophosphamide, daunomycin (daunorubicin), prednisolone, actinomycin D. azacytidine and vincristine at concentrations of 1 μM on mature neutrophil function were examined. Up to 5 h incubation with adriamycin, azacytidine, cyclophosphamide, daunomycin and prednisolone had no effect on either luminol chemiluminescence or superoxide secretion. However, after 15 min or 1 h (but not 5 h) incubation vincristine enhanced fMet-Leu-Phe stimulated chemiluminescence, whilst after 5 h incubation with actinomycin D the ability of neutrophils to generate reactive oxidants in response to all stimuli tested was impaired: after 5 h incubation with adriamycin reactive oxidant production was also impaired, but only when fMet-Leu-Phe was used as stimulant. All of the drugs tested except azacytidine inhibited neutrophil oxidant production after 5 h incubation in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF). Actinomycin D and cyclophosphamide also inhibited GM-CSF stimulated protein biosynthesis. These data indicate that cytotoxic drugs may compromise the potentially beneficial effects of CSFs on mature neutrophil function during therapy.  相似文献   

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Laboratory diagnosis of protein C deficiency is complicated by the fact that many patients referred for investigation are already being treated with oral anticoagulants. Protein C and factor VII have similar half lives and by using the protein C:factor VII ratio we hoped to be able to detect protein C deficiency in patients receiving oral anticoagulants. We have studied activity levels of protein C and factor VII to produce protein C:factor VII activity ratios in 105 patients receiving oral anticoagulants, 42 normal subjects, and nine patients with known inherited protein C deficiency. The mean ratios for these groups were 1.38, 1.12 and 0.63 respectively. In patients receiving oral anticoagulants, the protein C level showed a poor correlation with the international normalized ratio (INR) value. Reference ranges for protein C at different levels of anticoagulation were therefore considered unsuitable for the identification of inherited protein C deficiency. Five patients with inherited protein C deficiency were studied with and without oral anticoagulation; their protein C:factor VII ratios remained relatively unchanged, despite alterations in the level of the individual proteins. These results suggest that measurement of the protein C:factor VII ratio may help to identify patients with inherited protein C deficiency whilst on oral anticoagulants.  相似文献   

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