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1.
Plasma corticosteroid-binding globulin (CBG) concentrations decrease dramatically in patients with septic shock or burn injury. This decrease suggests that mediators of the acute phase response, such as cytokines and glucocorticoid hormones, might influence clearance as well as liver synthesis of CBG in humans. The present study investigated the effects of interleukin-6 (IL-6), IL-1 beta, and dexamethasone on CBG synthesis by a clone of human hepatoblastoma-derived (HepG2) cell line. In culture medium from HepG2 cells, the immunoconcentration of CBG and the levels of CBG messenger ribonucleic acid (mRNA) were dose dependently decreased in the presence of IL-6 concentrations ranging from 0.1-10 ng/mL. The percent decrease in CBG immunoconcentration was quantitatively similar to the percent decrease in CBG mRNA levels (29 +/- 6% and 39 +/- 15%, respectively, of control values). In contrast, and as expected, IL-6 dose dependently increased the mRNA levels (164 +/- 22% of control values) of alpha 1-antitrypsin, a positive acute phase protein, but did not affect the immunoconcentration of sex hormone-binding globulin, another liver protein. Dexamethasone alone did not significantly affect CBG secretion or mRNA levels, but did dose-dependently increase tyrosine amino-transferase mRNA levels, which increased to 252 +/- 16% of the control values. However, in combination with IL-6, dexamethasone had a significant additive effect on IL-6 inhibition of CBG secretion and mRNAs in HepG2 cells. IL-1 beta dose-dependently stimulated CBG secretion (156 +/- 10% of control values) with no significant effect on CBG mRNA levels. In addition, IL-1 beta significantly decreased the inhibitory effect of IL-6 on CBG secretion, but had no effect on the inhibitory effect of IL-6 on CBG mRNA levels. These results suggest that IL-1 beta acts on the posttranslation processing and/or secretion mechanisms of CBG in HepG2 cells. Together, the present results strongly support the hypothesis that the decrease in plasma CBG concentrations is associated with the increase in IL-6 and glucocorticoid levels reported in patients with septic shock and burn injury.  相似文献   

2.
The aim of this study was to compare the clinical efficacy and safety of low dose cyproterone acetate-estrogen combination (Diane) and the 5 alpha-reductase inhibitor finasteride in the treatment of hirsutism. Fourty-two women with hirsutism were included in the study. Twenty-one patients treated with cyproterone acetate (CPA) 2 mg and ethinyl estradiol (E) 35 micrograms daily on days 5-25 of the menstrual cycle, 21 with finasteride 5 mg daily. Hirsutism score, hormone levels, multiscreen blood chemistry and side effects were evaluated at three-monthly intervals for 9 months. A significant decrease in hirsutism score as compared to baseline was observed after 9 months with either CPA + E (Diane) (mean +/- SE, 15.81 +/- 1.19 vs 8.38 +/- 1.21) or finasteride treatment (17.81 +/- 1.05 vs 10.86 +/- 0.91) (p < 0.0005). The reductions in hirsutism scores (mean% +/- SE) were 14.23 +/- 2.29 vs 19.77 +/- 2.22 (p < 0.05) at 3, 40.23 +/- 4.58 vs 29.49 +/- 2.69 (p < 0.02) at 6 and 50.99 +/- 4.13 vs 39.87 +/- 3.30 (p < 0.02) at 9 months in CPA + E and finasteride groups, respectively. No significant changes were observed in hormone levels during finasteride treatment. Serum free testosterone significantly decreased at the third month of treatment, and remained suppressed for the duration of treatment in CPA + E group. DHEAS levels also decreased significantly after 6 and 9 months of therapy with CPA + E. SHBG significantly increased during CPA + E treatment. We conclude that both drugs are effective and well tolerated, but CPA + E appears to be more effective than 5 alpha-reductase inhibitor finasteride in long-term treatment of hirsute women. Diane is also a cost-effective drug.  相似文献   

3.
Impaired gut mucosal perfusion has been reported during cardiopulmonary bypass. To better define the adequacy of gut blood flow and oxygenation during cardiopulmonary bypass, we measured overall gut blood flow and ileal mucosal flow and their relationship to mucosal pH, mesenteric oxygen delivery and oxygen consumption in immature pigs (n = 8). Normothermic, noncross-clamped, right atrium-to-aorta cardiopulmonary bypass was maintained at 100 ml/kg per minute for 120 minutes. Animals were instrumented with an ultrasonic Doppler flow probe on the superior mesenteric artery, a mucosal laser Doppler flow probe in the ileum, and pH tonometers in the stomach, ileum, and rectum. Radioactive microspheres were injected before and at 5, 60, and 120 minutes of cardiopulmonary bypass for tissue blood flow measurements. Overall gut blood flow significantly increased during cardiopulmonary bypass as evidenced by increases in superior mesenteric arterial flow to 134.1% +/- 8.0%, 137.1% +/- 7.5%, 130.3% +/- 11.2%, and 130.2% +/- 12.7% of baseline values at 30, 60, 90, and 120 minutes of bypass, respectively. Conversely, ileal mucosal blood flow significantly decreased to 53.6% +/- 6.4%, 49.5% +/- 6.8%, 58.9% +/- 11.6%, and 47.8% +/- 10.0% of baseline values, respectively. Blood flow measured with microspheres was significantly increased to proximal portions of the gut, duodenum and jejunum, during cardiopulmonary bypass, whereas blood flow to distal portions, ileum and colon, was unchanged. Gut mucosal pH decreased progressively during cardiopulmonary bypass and paralleled the decrease in ileal mucosal blood flow. Mesenteric oxygen delivery decreased significantly from 67.0 +/- 10.0 ml/min per square meter at baseline to 42.4 +/- 4.6, 44.9 +/- 3.5, 46.0 +/- 3.6, and 42.9 +/- 3.9 ml/min per square meter at 30, 60, 90, and 120 minutes of bypass. Despite the decrease in mesenteric oxygen delivery, mesenteric oxygen consumption increased progressively from 10.8 +/- 1.4 ml/min per square meter at baseline to 13.4 +/- 1.2, 15.9 +/- 1.2, 16.7 +/- 1.4, and 16.6 +/- 1.54 ml/min per square meter, respectively. We conclude that gut mucosal ischemia during normothermic cardiopulmonary bypass results from a combination of redistribution of blood flow away from mucosa and an increased oxygen demand.  相似文献   

4.
OBJECTIVE: Sex hormone-binding globulin (SHBG) binds testosterone (T) to a greater degree than it does estradiol (E2), acting as an amplifier of E2 action. However, it is not known whether the relative capacity of SHBG for E2 vs. T is altered by the hormonal milieu. We hypothesized that an increase in circulating E2 levels results in a compensatory increase in the relative binding capacity of SHBG for these hormones, dampening the E2 amplification effect in hyperestrogenic conditions. STUDY DESIGN: Retrospective. RESULTS: As expected, during hMG stimulation there was a significant increase in total and free E2 (28 to 1,986 pg/mL, P < .001; and 0.3 to 20.8 pg/mL, P < .001, respectively) and total T levels (40.3 vs. 78.3 ng/dL, P < .001) from basal to late stimulation. Free T levels increased, but the difference did not reach significance. The binding capacity of SHBG for both E2 and T increased in a proportional manner (980 +/- 340 vs. 1,434 +/- 449 nmol/L, P < .009; and 352 +/- 190 vs. 512 +/- 128 nmol/L, P < .02; respectively) since the ratio of SHBG binding to E2 and T was unchanged. Although the SHBG molar concentration appeared increased, the difference did not reach significance (821 +/- 542 to 1,099 +/- 254 nmol/L). CONCLUSION: A short-term, although profound, increase in circulating E2 does not seem to be associated with an increase in the relative binding capacity of the carrier protein for either E2 or T, although an overall increase in binding for both steroids was observed. It is possible that longer periods of exposure to E2 may be necessary to demonstrate a change in the differential binding of this carrier protein with an alteration in the hormonal milieu.  相似文献   

5.
PURPOSE: To evaluate the changes in serum sex hormones of gonadal or adrenal origin, the gonadotropic hormones, and sex hormone-binding globulin (SHBG) in men and women with chronic temporal lobe epilepsy (TLE), who are undergoing monotherapy with carbamazepine or receiving carbamazepine in combination with other anticonvulsant drugs. METHODS: Gonadal hormones (estradiol, testosterone, free testosterone, and inhibin B), adrenal hormones [cortisol, dehydroepiandrosterone sulfate (DHEAS), androstenedione, and 17alpha-hydroxyprogesterone], and gonadotropic hormones (luteinizing hormone [LH] and follicle-stimulating hormone [FSH]) were measured in 22 women and 26 men with TLE. The study also measured prolactin; human growth hormone and its major mediator, insulin-like growth factor-I; thyroid hormones (free thyroxine and free triiodothyronine); thyroid-stimulating hormone (TSH); and SHBG. The results were compared with those obtained from 60 healthy women and 106 healthy men. RESULTS: In the female patients, TSH, DHEAS, follicular-phase LH, and luteal-phase estradiol were significantly lower than in the control groups, with prolactin and SHBG significantly higher. In the male patients, DHEAS, 17alpha-hydroxyprogesterone, free testosterone, inhibin B, and the testosterone/LH ratio were significantly lower than in the control group, with LH, FSH, and SHBG significantly higher. Increased FSH in 31% of the men indicates an impairment of spermatogenesis; lowered inhibin B in 12% indicates an impaired Sertoli's cell function; and the decreased testosterone/LH ratio in 50% indicates an impaired Leydig's cell function. CONCLUSIONS: The case patients had endocrine disorders, mainly concerning the gonadotropic and gonadal functions in both sexes; the adrenal function, with lowered DHEAS levels in both sexes; and lowered 17alpha-hydroxyprogesterone levels in the men. SHBG levels were increased in patients taking anticonvulsant medications.  相似文献   

6.
7.
Polycythemia and hyperhomocysteinemia are risk factors for thrombosis. Since red blood cells actively metabolize methionine to homocysteine, we investigated whether or not patients with polycythemia have increased plasma levels of homocysteine, which might contribute to their increased thrombotic risk. In ten patients with polycythemia, the plasma homocysteine levels were measured before phlebotomy, three days after the procedure and 1-2 months later. The baseline mean plasma homocysteine levels in patients (9.7 +/- 1.6 mumol/L [+/-SD]) did not differ significantly from that found in 30 sex- and age-matched healthy controls (12.2 +/- 6.9). Despite a fall in the patients' mean [+/-SD] hematocrit from 0.50 +/- 0.02 at baseline to 0.47 +/- 0.03 three days after phlebotomy (significant at 95%) and to 0.48 +/- 0.02 after 1 to 2 months (not significant), the mean plasma homocysteine levels did not change significantly (9.9 +/- 2.3 mumol/L at 3 days and 9.7 +/- 2.1 mumol/L at 1-2 months). It is unlikely that high plasma homocysteine levels contribute to the increased thrombotic risk of polycythemic patients.  相似文献   

8.
BACKGROUND: Cardiopulmonary bypass contributes to platelet loss and dysfunction by exposure to shear stresses, foreign surfaces, and hypothermia. This study tested the hypothesis that pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) accelerates recovery of the platelet population after hypothermic extracorporeal circulation (HEC). METHODS: In a blinded study, subcutaneous injections of drug or placebo were given to dogs daily for 3 days preoperatively (day 0, 1, and 2) with no drug on day 3. On day 4, the animal was prepared for arteriovenous HEC. After heparinization, HEC was initiated at 30 to 40 mL x kg(-1) x min(-1). Hypothermic extracorporeal circulation (25 degrees C) was continued for 90 minutes. RESULTS: Preoperative platelet count (x10(3) platelets/microL) did not differ from predrug count in placebo (256+/-27 versus 255+/-20) or PEG-rHuMGDF (271+/-30 versus 291+/-38). During 60 minutes of HEC, the platelet count decreased to approximately 10% of baseline in placebo (29+/-5) and PEG-rHuMGDF (46+/-8), and recovered to approximately 70% of baseline after rewarming (90 minutes of HEC: placebo, 185+/-17, versus PEG-rHuMGDF, 169+/-22). After HEC, platelet count was greater in PEG-rHuMGDF-treated animals (p < 0.05) without altering function (aggregation responses). Within the first 6 hours after HEC, platelet count in PEG-rHuMGDF-treated animals was rising and increased to 260+/-29 (p < 0.01), but was unchanged in placebo animals (186+/-21). Thereafter, platelet count in placebo animals declined to a nadir of 124+/-15 (72 hours after HEC), whereas platelet count in PEG-rHuMGDF animals approximated the preoperative value (>200) at all times. CONCLUSIONS: Appropriately timed presurgical administration of PEG-rHuMGDF counteracts post-HEC relative thrombocytopenia without increasing platelet population and enhancing aggregation preoperatively or during extracorporeal circulation.  相似文献   

9.
BACKGROUND: Chronic symptomatic gastroparesis occurs in 3-5% of patients following vagotomy and antrectomy. Erythromycin, a macrolide antibiotic, improves gastric emptying in patients with idiopathic and diabetic gastroparesis. Erythromycin's effect on gastric emptying in patients with post-vagotomy-antrectomy gastroparesis is unknown. The aim of this study was to determine if a single dose of intravenous erythromycin (1 mg/kg or 6 mg/kg) accelerates solid meal gastric emptying in patients with chronic symptomatic post-vagotomy-antrectomy gastroparesis. METHODS: Six patients were entered into the study, three males and three females, with a mean age of 50 years. Four patients were randomized to receive erythromycin 6 mg/kg and two patients 1 mg/kg. The mean time since initial surgery was 9.2 years (range 1-16 years) with five patients having undergone a Roux-en-Y revision. RESULTS: Intravenous erythromycin significantly lowered percentage gastric retention at 120 min, from a baseline of 90.5 +/- 6% (S.E.M.) to 40.1 +/- 4.8% after erythromycin (P = 0.0002). Erythromycin improved gastric emptying in each patient by at least 40%. Intravenous erythromycin significantly accelerated the rate of gastric emptying in the first 30 min after meal ingestion from a baseline rate of 0.072 +/- 0.06%/min to 0.96 +/- 0.31%/min after erythromycin (P = 0.028). For each of the subsequent 30 minute time periods, erythromycin had no significant effect on the rate of gastric emptying. CONCLUSION: Intravenous erythromycin significantly improves the initial phase of solid meal gastric emptying in patients with chronic symptomatic post-antrectomy-vagotomy gastroparesis.  相似文献   

10.
DW Busija  W Meng 《Canadian Metallurgical Quarterly》1993,24(11):1740-4; discussion 1744-5
BACKGROUND AND PURPOSE: We examined responses of rabbit pial arterioles to three different stimuli before and after induction of cortical spreading depression. METHODS: In urethane-anesthetized rabbits equipped with a closed cranial window, we measured pial arteriolar diameter during baseline conditions, topical application of calcitonin gene-related peptide (CGRP), topical application of acetylcholine, and inhalation of 10% CO2 in air (arterial hypercapnia) before cortical spreading depression and 30, 60, and 120 minutes after cortical spreading depression. Cortical spreading depression was induced by localized application of a 5% KCl solution anterior to the arteriole being measured. RESULTS: Average baseline diameter was approximately 90 microns. During cortical spreading depression, arteriolar diameter increased to a peak value that was 50 +/- 4% above baseline (n = 32). Before cortical spreading depression, arteriolar diameter changed 47 +/- 7% (n = 9) during hypercapnia, 17 +/- 3% (n = 4) during 10(-9) mol/L CGRP, 42 +/- 10% (n = 7) during 10(-7) mol/L CGRP, 29 +/- 6% (n = 4) during 10(-6) mol/L acetylcholine, and 61 +/- 13% (n = 6) during 10(-4) mol/L acetylcholine. Arteriolar responsiveness to any of these stimuli was not changed significantly by prior cortical spreading depression. CONCLUSIONS: Dilator capacity of pial arterioles is still intact in urethane-anesthetized rabbits after cortical spreading depression.  相似文献   

11.
To evaluate the effect of exercise intensity on post-exercise cardiovascular responses, 12 young normotensive subjects performed in a randomized order three cycle ergometer exercise bouts of 45 min at 30, 50 and 80% of VO2peak, and 12 subjects rested for 45 min in a non-exercise control trial. Blood pressure (BP) and heart rate (HR) were measured for 20 min prior to exercise (baseline) and at intervals of 5 to 30 (R5-30), 35 to 60 (R35-60) and 65 to 90 (R65-90) min after exercise. Systolic, mean, and diastolic BP after exercise were significantly lower than baseline, and there was no difference between the three exercise intensities. After exercise at 30% of VO2peak, HR was significantly decreased at R35-60 and R65-90. In contrast, after exercise at 50 and 80% of VO2peak, HR was significantly increased at R5-30 and R35-60, respectively. Exercise at 30% of VO2peak significantly decreased rate pressure (RP) product (RP = HR x systolic BP) during the entire recovery period (baseline = 7930 +/- 314 vs R5-30 = 7150 +/- 326, R35-60 = 6794 +/- 349, and R65-90 = 6628 +/- 311, P < 0.05), while exercise at 50% of VO2peak caused no change, and exercise at 80% of VO2peak produced a significant increase at R5-30 (7468 +/- 267 vs 9818 +/- 366, P < 0.05) and no change at R35-60 or R65-90. Cardiovascular responses were not altered during the control trial. In conclusion, varying exercise intensity from 30 to 80% of VO2peak in young normotensive humans did not influence the magnitude of post-exercise hypotension. However, in contrast to exercise at 50 and 80% of VO2peak, exercise at 30% of VO2peak decreased post-exercise HR and RP.  相似文献   

12.
Antiandrogens or progestins with an antiandrogenic component usually have only a weak antigonadotropic activity. It is thus possible that the antiandrogenic effect on the cellular level is cancelled or at least reduced by an increased ovarian androgen production. The aim of the four submitted clinical studies of the progestin and antiandrogen dienogest alone (0.5-2 mg/day) or of a combined regimen of ethinylestradiol (0.03 mg) plus dienogest (2 mg) (EE/DNG) was to examine the influence on the serum androgen and SHBG concentrations as well as on the serum FSH, LH, progesterone and 17 beta-estradiol concentrations in young women. Like the progesterone derivatives, dienogest has a relatively low antigonadotropic activity. Inhibition of ovulation is mainly produced by peripheral mechanisms such as the reduction of preovulatory 17 beta-estradiol secretion. Dienogest alone has no significant effects on the serum SHBG and androgen concentrations. Unlike this, the combination of EE plus DNG markedly increases SHBG concentrations (to 2.1-3.7 fold the basal levels). The decrease in serum androgens with total testosterone (by 17 and 40%), free testosterone (by 48 and 54%) and dehydroepiandrosterone sulfate (by 51%) corresponds to the values shown in the literature for other oral contraceptives with modern progestins. EE/DNG does not affect the serum concentrations of 5 alpha-dihydrotestosterone (DHT), although the marker of the peripheral transformation from T to DHT, androstanediol glucuronide, is distinctly reduced (by 38%). In a double-blind comparison no differences are found between EE/DNG and a regimen combining 0.02 mg of ethinylestradiol and 0.150 mg of desogestrel. Solely the SHBG concentrations, with EE/DNG, as expected, are significantly higher. In a sequential regimen, dienogest, chlormadinone acetate and desogestrel (progestins without binding to SHBG) enhance the inhibitory effect of ethinylestradiol sulfonate on free testosterone, whereas norethindrone acetate and levonorgestrel (progestins with a strong binding to SHBG) reduce this effect of the estrogen significantly. These results exclude the possibility that the very distinct antiandrogenic effect of dienogest on a cellular level is neutralised or reduced by an increased systemic supply of androgen.  相似文献   

13.
OBJECTIVE: To investigate the interrelation between estrogen synthesis by the fetoplacental unit and uteroplacental hemodynamics in term pregnancy. METHODS: Transvaginal color Doppler flow imaging and pulsed Doppler ultrasonographic assessments were made on ten normal full-term pregnant women before and 3, 5, 10, 30, and 60 minutes after the administration of a 200-mg intravenous dose of dehydroepiandrosterone sulfate (DHAS) in 20 mL of 5% dextrose. Ten normal full-term pregnant women received 20 mL of 5% dextrose as controls. The pulsatility index (PI) values for the uterine artery, heart rate, and mean arterial pressure were recorded. Plasma estradiol (E2) was measured before and 10 minutes after the infusion. RESULTS: In the DHAS group, uterine artery PI decreased from baseline by 26% (P < .05) after 5 minutes, and the mean reduction was 36% (P < .05) after 10 minutes and 15% (P < .05) after 30 minutes. The PI returned to the baseline value 60 minutes later. In the control group, there was no change in uterine artery PI. No change was found in heart rate or mean arterial blood pressure in the control or DHAS groups. The mean plasma E2 increased from 22.3 +/- 6.6 to 56.2 +/- 24.1 ng/mL (P < .05) 10 minutes after the infusion in DHAS subjects, whereas there was no significant change in plasma E2 in the controls. CONCLUSION: Dehydroepiandrosterone sulfate induces a significant decrease in the uterine artery PI, which suggests a possible decrease in uterine vascular impedance in term pregnancy.  相似文献   

14.
OBJECTIVE: To measure and compare plasma levels of sex hormones after the administration of different hormone replacement therapy (HRT) regimens. STUDY DESIGN: Ninety women with natural menopause were randomized into this comparative study. Eighty-five women completed one year of follow-up. Patients were randomly assigned to five groups. The first received 0.6 mg/d of conjugated equine estrogen (CEE) cyclically (n = 15). The second received 50 micrograms/d of transdermal estradiol (E2) cyclically (n = 17), and the third received 0.6 mg/d of CEE continuously (n = 17). All these groups also received 2.5 mg of medroxyprogesterone acetate (MPA) sequentially for the last 12 days of HRT, while the fourth therapy group received 0.625 mg/d of CEE and 2.5 mg/d of MPA continuously (n = 19). The fifth group constituted a treatment-free control group (n = 22). Levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), E2, estrone (E1), prolactin (PRL), testosterone (T), androstenedione (A4), dehydroepiandrosterone sulfate (DHEA-S) and sex hormone binding globulin (SHBG) were determined prior to HRT and during the last week of the 6th and 12th months of HRT, between days 21 and 24 of estrogen administration. RESULTS: After HRT we found decreases in FSH, LH and PRL levels, increases in E2, E1 and SHBG, and no modifications in T, A4 and DHEA-S plasma levels. There were no significant differences between the treatment groups in FSH, LH, E2, PRL, T, A4 or DHEA-S. E1 and SHBG were significantly higher in the groups with oral HRT. CONCLUSION: All the observed changes in hormone levels are to be expected after HRT except for the decrease in PRL levels. Finally, although MPA dosage was not the focus of the present study, our results suggest that the dosage of 2.5 mg/d of MPA in sequential regimens is clearly inadequate to protect the endometrium from hyperplastic changes.  相似文献   

15.
16.
Plasma levels of estrone (E1), estradiol-17beta (E2), and estriol (E3), as well as follicle-stimulating hormone (FSH), luteinizing hormone (LH), and prolactin were measured in 30 control subjects and in 20 postmenopausal patients with adenocarcinoma of the endometrium. Within the sensitivity of the assay (5 to 10 pg.), no E3 was found. Mean levels of E1 and E2 in the patients with carcinoma (42.64+/-3.8 (S.E.M.) and 17.3+/-1.7 (S.E.M.) pg. per mililiter) were significantly higher than those measured in the control subjects (E1=26.97+/-2.4 (S.E.M.) pg. per mililiter, p less than 0.001; E2=12.08+/-1.2 (S.E.M.) pg. per milliliter, p less than 0.02). Effects of age, diabetic status, and obesity were taken into consideration. Significant differences in FSH and marginally significant differences in prolactin levels were observed between the two groups. Mean levels of FSH, LH, and prolactin in the control group and the group with adenocarcinoma, respectively, were as follows: FSH=152.3+/-7.0 (S.E.M.) versus 98.1+/-8.9 (S.E.M.) mI.U. per milliliter, p less than 0.001; LH=64.7+/-3.1 (S.E.M.) versus 66.5+/-5.2 mI.U. per milliliter, difference not significant; and prolactin=14.3+/-0.9 (S.E.M.) versus 17.8+/1.7 (S.E.M.) ng. per milliliter, p less than 0.06. These results, as well as previously reported alterations in human growth hormone secretion, suggest aberrations in hypothalamic function in endometrial carcinoma.  相似文献   

17.
This report concerns the evaluation of various estrogens, estrone (El), estradiol (E2), and estrone sulfate (E1S), as well as E1S-sulfatase and aromatase activities in pre- and postmenopausal women with breast cancer. The levels (in picomoles per g; mean +/- SEM) of the various estrogens in the breast tissue from premenopausal patients (n = 11) are: El, 1.4 +/- 0.5; E2, 1.2 +/- 0.6; and E1S, 1.2 +/- 0.3. In postmenopausal patients (n = 23), the values are, respectively, 1.0 +/- 0.4, 1.4 +/- 0.7, and 3.3 +/- 1.9. These concentrations of estrogens in the tumors of postmenopausal patients are significantly higher than those found in plasma. The activity of E1S-sulfatase in both pre- and postmenopausal patients was 50-200 times higher than that of aromatase. E1S-sulfatase and aromatase activities are significantly higher in post-menopausal than in cycling patients. It is concluded that despite the low levels of circulating estrogens in postmenopausal patients, the tissue concentrations of these steroids are several-fold higher than those in plasma, suggesting tumor accumulation of these estrogens. The physiopathology and clinical significance of these high levels of the various estrogens (E1, E2, and E1S) as well as sulfatase and aromatase activities in postmenopausal patients with breast cancer is yet to be explored.  相似文献   

18.
OBJECTIVES: To determine whether a combination of ciprofloxacin hydrochloride and metronidazole hydrochloride would be as effective or more effective than a combination of gentamicin sulfate and metronidazole hydrochloride for preventing infection in patients with penetrating abdominal trauma, to evaluate the factors associated with increased risk of infection, and to determine the serum peak and trough levels of gentamicin with the dosage regimen of 2.5 mg/kg every 12 hours. DESIGN: Randomized double-blind study. SETTING: Level I trauma center. PATIENTS: Eighty-four patients with penetrating intra-abdominal injuries (gunshot wound, 69; stab wound, 15) thought to require laparotomy. INTERVENTIONS: The patients were randomized during treatment in the emergency department to be given a combination of ciprofloxacin hydrochloride, 400 mg every 12 hours, and metronidazole hydrochloride, 500 mg every 6 hours, or a combination of gentamicin sulfate, 2.5 mg/kg every 12 hours, and metronidazole hydrochloride, 500 mg every 6 hours. RESULTS: Of 68 patients with intra-abdominal injuries who could be observed for at least 48 hours after laparotomy, posttraumatic infections developed in 12 (18%), and nosocomial infections developed in 6 (9%). The incidence of posttraumatic infections in patients who were given gentamicin and metronidazole (5/33 [15%]) was not significantly lower than the incidence in patients who were given ciprofloxacin and metronidazole (7 of 35 [20%]; P=.75). The presence of any infection increased the mean+/-SD length of hospital stay from 8.7+/-3.5 days to 23.3+/-10.9 days and increased the mean+/-SD hospital charges from $24 507+/-$9860 to $104920+/-$49083 (P<.001). Univariate analysis showed the factors most significantly associated with infection were as follows: (1) the use of blood transfusions (P<.001), (2) the penetrating abdominal trauma index of 35 or more (P<.002), (3) injury to the colon requiring a colostomy (P=.004), and (4) a trauma score of less than 12 (P<.02). Multivariate analysis showed the only significant factor was the receipt of blood transfusions (F=10.165; P<.005). CONCLUSIONS: Ciprofloxacin and gentamicin, each in combination with metronidazole, were equivalent in their ability to prevent infections after penetrating abdominal trauma; other factors, especially the receipt of blood transfusions, had much more effect on the incidence of infection. Infection greatly increases the length of hospital stay and hospital charges. The use of an increased dosing regimen of 2.5 mg/kg every 12 hours of gentamicin sulfate was effective at obtaining a therapeutic peak serum concentration.  相似文献   

19.
Because the beta3-antagonist abciximab (c7E3 Fab) has significantly improved late outcomes after coronary angioplasty, the beta3 integrins have been implicated in the arterial response to injury. However, the mechanisms underlying this benefit are unknown. The observation that c7E3 binds beta3 integrins on vascular cells (alphavbeta3) with affinity equal to that for the platelet glycoprotein IIb/IIIa integrin has led to the hypothesis that c7E3 may act directly on the artery wall to prevent restenosis after angioplasty. To test this hypothesis, we studied the effects of c7E3 on structural changes within the artery wall after angioplasty or stent angioplasty in 23 male cynomolgus monkeys with established atherosclerosis. Animals were randomly assigned to receive either a bolus of c7E3 (0.4 mg/kg IV, n=11) followed by a 48-hour infusion (0. 2 microg. kg-1. min-1) or an equal volume of vehicle (n=12). Animals received weight-adjusted aspirin and heparin and then underwent unilateral iliac artery experimental angioplasty and subclavian artery stent angioplasty (Palmaz). Iliac artery lumen diameter (LD) was determined by angiography at baseline (LDPre), after angioplasty (LDPost), and 35 days later (LDDay35). Arteries were then fixed by perfusion and removed for analysis. Lumen, intima, media, and external elastic lamina (EEL) areas were measured in iliac artery cross sections. Values from each injured iliac artery were normalized to the contralateral uninjured iliac artery to control for interanimal variability in baseline artery size and atherosclerosis extent. Intimal area was also measured in subclavian stent cross sections. c7E3 blocked platelet aggregation and prolonged the bleeding time from 2.8+/-1.1 to 19.8+/-2.5 minutes, P<0.001. Experimental angioplasty increased LDPost an average of 28%, and the initial gain was similar in both groups (P=NS). Despite an anti-platelet effect, c7E3 did not inhibit iliac lumen narrowing (LDDay35-LDPost: c7E3, -0.69+/-0.17 versus vehicle, -0.99+/-.17 mm, P=0.35); intimal hyperplasia (neointima area: c7E3, 1.12+/-.28 versus vehicle, 1.22+/-.20 mm2, P=0.77); or decrease in artery wall size (EEL area [percent of uninjured control]: c7E3, 101+/-7% versus vehicle, 121+/-7%). Stent intimal hyperplasia was also unaltered by c7E3 treatment (neointimal area: c7E3, 1.09+/-0.16 versus vehicle, 1. 28+/-0.11 mm2, P=0.36). These results suggest that the benefits of c7E3 treatment in coronary angioplasty were not from inhibition of intimal hyperplasia or improved artery wall remodeling. Alternative mechanisms should be explored to explain improved late outcomes after angioplasty in patients treated with c7E3.  相似文献   

20.
Hyperthyroidism is associated with elevated plasma levels of endothelium-derived proteins such as von Willebrand factor (vWF), fibronectin (FN) and endothelin-1 (ET-1). This study was designed to characterize the mechanisms involved in this phenomenon at the cellular level. vWF, FN and ET-1 secretion and mRNA expression were measured in human umbilical vein endothelial cells (HUVECs) exposed to tri-iodothyronine (T3) for 13 +/- 1 days, using ELISA, Western blot, RIA and Northern blot analysis respectively. Exposure of HUVECs to T3 significantly increased vWF secretion (50 ng T3/ml: 117 +/- 5%, P < 0.01; 100 ng T3/ml: 127 +/- 26%, P < 0.01) as well as vWF mRNA expression (50 ng/ml: 116 +/- 13%, P < 0.001; 100 ng/ml: 136 +/- 30%, P < 0.002) (results are means +/- S.D. analysed by the Wilcoxon signed rank test). FN secretion was significantly affected by 50 (145 +/- 42% of control, P < 0.05) and 100 (116.8 +/- 16% of control, P < 0.05) ng T3/ml, and FN mRNA expression by 50 ng T3/ml (123 +/- 20%, P < 0.05). Long-term incubation with T3 increased both ET-1 secretion (25 ng/ml: 124 +/- 25%, P < 0.001; 50 ng/ml: 165 +/- 53%, P < 0.05; 100 ng/ml: 116 +/- 17%, P < 0.05) and prepro-ET-1 mRNA expression (25 ng/ml: 112 +/- 16%, P < 0.05; 50 ng/ml: 134 +/- 43%, P < 0.02; 100 ng/ml: 120 +/- 20%, P < 0.02). Protein kinase C (PKC) isoforms epsilon and beta II were not significantly affected by T3, whereas PKC alpha was increased in whole cell lysates and in membrane fractions of cells incubated with 100 but not 50 ng T3/ml. Prepro-ET-1 mRNA stability, cell numbers and proliferation, measured by [3H]thymidine assays, remained unaffected in HUVECs after exposure to T3. These data indicate thyroid hormone-induced upregulation of mRNA expression and protein synthesis of vWF, FN and ET-1, by PKC alpha-, beta II- and epsilon-independent pathways, explaining, at least in part, increased plasma concentrations of endothelial proteins and peptides in the hyperthyroid state.  相似文献   

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