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1.
OBJECTIVE: The positive short-term effects of postmenopausal hormone replacement therapy (HRT) on serum lipids are well known, but it has been suggested that they vanish with time. Cholecalciferol (vitamin D3) is widely used to prevent postmenopausal osteoporosis but the influence of vitamin D3 on serum lipids is poorly known. The long-term effects of HRT and vitamin D3 on the concentrations of serum lipids were studied in a population-based prospective 3-year study. DESIGN AND METHODS: 464 women were randomized into four treatment groups: (i) HRT (sequential combination of 2 mg estradiol valerate and 1 mg cyproterone acetate), (ii) Vit D3 (vitamin D3 300 IU/day), (iii) HRT+Vit D3 (both as above), (iv) placebo (calcium lactate 500 mg/day). RESULTS: 320 women completed the study. After three years of treatment, serum concentrations of low density lipoprotein (LDL) cholesterol decreased in the HRT group (10.1%, P<0.001) and the HRT+Vit D3 group (5.9%, P=0.005), increased in the Vit D3 group (4.1%, P=0.035) but remained unchanged in the placebo group. The concentrations of total cholesterol decreased by 5.8% in the HRT group (P<0.001) and by 3.3% in the HRT+Vit D3 group (P=0.023), but did not change in the other two groups. Serum concentrations of high density lipoprotein (HDL) cholesterol decreased in the Vit D3 group (5.2%, P=0.001), HRT+Vit D3 group (3.7%, P=0.046), and the placebo group (4.5%, P=0.006) but did not change significantly in the HRT group. The HDL/LDL ratio increased in the HRT group (10.5%, P=0.006) and decreased in the Vit D3 group (10.5%, P<0.001) whereas no changes occurred in the other two groups. In addition, serum triglycerides increased similarly in all groups (14.0-18.8%, P<0.05-0.001). CONCLUSIONS: Our results confirm the positive long-term effect of HRT with sequential estradiol valerate and cyproterone acetate on serum lipid concentrations. In addition, the results suggest that vitamin D3 supplementation may have unfavorable effects on lipids in postmenopausal women. Pure vitamin D3 treatment was associated with increased serum LDL cholesterol. Furthermore, the beneficial effects of HRT on serum LDL cholesterol content were reduced when estradiol valerate was combined with vitamin D3. However, the relevance of these associations to cardiovascular morbidity remains to be established.  相似文献   

2.
Postmenopausal hormone replacement therapy (HRT) has favorable effects on the serum lipid profile, and it also decreases the risk of cardiovascular diseases. The apolipoprotein E genotype has influence on serum levels of lipids and lipoproteins; apoE allele epsilon4 (apoE4) is associated with high total and LDL cholesterol levels. Genotype also influences the lipid responses to treatment with diet and statins, but the effect of HRT in different apoE genotypes is unknown. We studied the effects of HRT on the concentrations of serum lipids in apoE4-positive early postmenopausal women (genotypes 3/4 and 4/4) compared with apoE4-negative women (genotypes 2/3 and 3/3) in a population-based, prospective 5-year study. In all, 232 early postmenopausal women were randomized into 2 treatment groups: an HRT group (n=116), which received a sequential combination of 2 mg estradiol valerate (E2Val) from day 1 to 21 and 1 mg cyproterone acetate (CPA) from day 12 to 21 (Climen), and a placebo group (n=116), which received 500 mg/d calcium lactate. Serum concentrations of total, LDL, and HDL cholesterol and triglycerides were measured at baseline and after 2 and 5 years of treatment. A total of 154 women completed the final analysis. During the follow-up period, serum total cholesterol and LDL cholesterol concentrations decreased in the HRT group in apoE4-negative women (8.1% and 17.1%, respectively; P<0.001) but did not change in the HRT group in apoE4-positive women or in the placebo group. Serum HDL cholesterol concentrations decreased in the placebo group (apoE4-negative, 3.9%, P=0.015; apoE4-positive, 8.1%, P=0.004) but did not change significantly in the HRT group. Serum triglyceride levels tended to increase in both study groups and genotypes (15.1% to 36.2%, P<0.038 to 0.001), but no differences were observed between the study groups or genotypes, respectively. Our finding was that in postmenopausal Finnish women LDL cholesterol levels in apoE4-negative subjects respond more favorably to HRT than those in apoE4-positive subjects. This finding has potential importance in postmenopausal women with hypercholesterolemia, if confirmed in other studies.  相似文献   

3.
Hormone replacement therapy has been shown to decrease the risk of coronary heart disease (CHD) in menopausal women. In this cross-sectional study, we addressed the following question: What effects would combined oral hormone replacement therapy have on plasma lipid and lipoprotein profiles independent of the other known CHD risk factors? We analyzed the plasma lipoproteins of two groups of menopausal women who were randomly selected from a large database of individuals. One group (n = 10) was not taking any hormone replacement therapy (NO HRT), while the second group (n = 8) was taking a daily dose of 0.625 mg conjugated estrogen and 2.5 mg medroxyprogesterone orally (PremPro, Wyeth-Ayerst, Philadelphia, PA) for at least 6 months (HRT). The two groups were not different in age, body weight, percent body fat, body mass index (BMI), waist to hip ratio, blood pressure, or insulin and glucose levels. High-density lipoprotein (HDL)-cholesterol was significantly higher (P < .05) in the HRT group. The total cholesterol (TC) to HDL-cholesterol ratio was significantly lower for HRT versus NO HRT (P < .05). Apolipoprotein (apo) A-1, the apo A-1/B ratio, and lecithin:cholesterol acyltransferase (LCAT) activity were significantly higher in HRT (P < .05). Lipoprotein subclass profiles measured by nuclear magnetic resonance (NMR) spectroscopy showed an increase in larger HDL subpopulations (H3 and H4) in HRT (P < .05), which are considered antiatherogenic. No differences were seen in the cholesterol concentration or size of low-density lipoprotein (LDL) subpopulations in HRT compared with NO HRT. These results indicate that the combined estrogen and progesterone treatment leads to beneficial effects on plasma lipoproteins. The beneficial effects include (1) increases in HDL-cholesterol and predominance of HDL2, (2) no adverse effects on LDL subpopulation distribution, and (3) increases in apo A-1 levels and LCAT activity, which indicate an improvement in reverse cholesterol transport.  相似文献   

4.
The effect of Paeonia lactiflora (PL) on platelet cytosolic free calcium and erythrocyte membrane Ca(2+)-Mg(2+)-ATPase activity in hyperlipid rabbits were observed. Results showed the level of platelet cytosolic free calcium in the PL group (276.25 +/- 27.00 nmol/L) was significantly lower than that in the cholesterol group (390.88 +/- 70.00 nmol/L), P < 0.01, the basal and calmodulin-stimulated activities of erythocyte membrane Ca(2+)-Mg(2+)-ATP ase in PL group (0.79 +/- 0.05 mumol.pi-1.mg-1.h-1 and 1.34 +/- 0.10 mumol.pi-1.mg-1.h-1) were higher than that in the cholesterol group (0.65 +/- 0.09 mumol.pi-1.mg-1.h-1 and 1.04 +/- 0.13 mumol.pi-1.mg-1.h-1).  相似文献   

5.
The effects of 2 months treatment with simvastatin (40 mg, 20 mg p.o. daily) or placebo on erythrocyte membrane cholesterol content and acyl chain composition have been studied in 36 patients with a clinical history of atherosclerosis enrolled in the Oxford Cholesterol Study. All patients received advice corresponding to a standard phase 1 cholesterol-lowering diet. As expected the mean serum total cholesterol fell substantially (-26.5%, 20 mg simvastatin, P < 0.05; -32.7%, 40 mg simvastatin, P < 0.05) compared to placebo (-6.3%, ns). However, mean erythrocyte cholesterol content did not change significantly in any group (2 months therapy: 20 mg simvastatin, -0.62%; 40 mg simvastatin, +2.2%; placebo, -4.2%). Erythrocyte cholesterol was also unaltered after 5 months of therapy. Erythrocyte osmotic fragility was unchanged in the treatment and placebo groups. In the placebo group dietary advice alone was associated with a significant increase in the linoleic acid content of erythrocytes from 9.4 mole% of total acyl chains to 11.8 mole% (P < 0.05). Treatment with simvastatin was associated with an increase in the arachidonic acid content of the erythrocyte membrane from 12.2 to 15.3 mole% (P < 0.05). Treatment with simvastatin does not alter erythrocyte cholesterol content, but does alter acyl chain distribution. These results suggest that the chemical potential of cholesterol in serum is not markedly altered by HMG-CoA reductase inhibition.  相似文献   

6.
OBJECTIVES: To compare the single and joint effect of 1-year diet and exercise intervention on carbohydrate metabolism and associated coronary risk variables. DESIGN: Unmasked, randomized, 2 x 2 factorial intervention trial with 1-year duration for each participant. SETTING: The participants were recruited from a screening examination of 40-year-old persons in Oslo, Norway. SUBJECTS: Two hundred and nineteen sedentary men and women, with diastolic blood pressure 86-99 mmHg, HDL cholesterol < 1.20 mmol L-1, triglycerides > 1.4 mmol L-1, total cholesterol 5.20-7.74 mmol L-1 and BMI > 24. Participants were randomly allocated to control (n = 43), diet (n = 55), exercise (n = 54) and diet+exercise (n = 67). INTERVENTIONS: Exercise: supervised endurance exercise three times a week. Diet: reduce weight, increase the intake of fish and reduce total fat intake. MAIN OUTCOME MEASURES: One-year changes in insulin and glucose before and after a standardized glucose load. RESULTS: As compared with controls fasting insulin in pmol L-1 decreased significantly in the combined diet and exercise group (3.9 +/- 6.2 versus -22.6 +/- 4.7 respectively, P = 0.003). Insulin in pmol L-1 after glucose load decreased significantly in all intervention groups compared to controls (diet: -82.2 +/- 49.9 P = 0.02; exercise: -92.4 +/- 60.1 P = 0.03; diet + exercise: -179.6 +/- 46.1 P = 0.0004). Fasting glucose in mmol L-1 decreased significantly in the diet alone group (0.21 +/- 0.07 P = 0.006) and in the diet+exercise group (-0.26 +/- 0.08 P = 0.005). In a subgroup analysis of the good responders, the observed changes with respect to total cholesterol (-0.76 mmol L-1), HDL cholesterol (0.16 mmol L-1), triglycerides (-0.72 mmol L-1), systolic and diastolic blood pressure (-8.5/ -6.8 mmHg) were all statistically significant compared to the control with P < 0.001). CONCLUSIONS: Exercise and diet intervention and in particular the combination of the two, were effective in improving carbohydrate metabolism. Associated risk factors were also affected in a beneficial direction.  相似文献   

7.
Three groups of age- and weight-matched men (aged 40 to 70 years) without diabetes were studied: controls (n = 10), plasma triglycerides (TG) less than 180 mg/dL and no cardiovascular disease (CVD); HTG-CVD (n = 11), hypertriglyceridemic (HTG) (TG > 240 mg/dL) without CVD; and HTG+CVD (n = 10), HTG (TG > 240 mg/dL) with documented CVD. HTG+CVD subjects had higher fasting and post-oral glucose tolerance test insulin levels than the other two groups, respectively. Very-low-density lipoprotein (VLDL)+chylomicrons (CMs), intermediate-density lipoprotein (IDL), low-density lipoprotein (LDL), and three high-density lipoprotein (HDL) subfractions (HDL-L, HDL-M, and HDL-D, from least to most dense) were isolated by gradient ultracentrifugation. Fasting lipoproteins were similar in HTG groups, except for higher VLDL lipid to apolipoprotein (apo) B ratios (P < .04) in the HTG+CVD group. Subjects were fed a high-fat mixed meal, and lipoprotein composition was determined at 3, 6, 9, and 12 hours postprandially. Postprandial responses of the core lipids (TG and cholesterol esters [CE]) in all of the lipoprotein subfractions were similar in the two HTG groups at each time point. However, both controls and HTG-CVD subjects had increases in HDL-M phospholipid (PL) at 9 and 12 hours with no change in HDL-D PL. The HTG+CVD group, on the other hand, had no increase in HDL-M PL and had a substantial reduction in HDL-D PL. These changes resulted in significant increases in HDL-M and HDL-D PL to apo A-I ratios in both controls and HTG-CVD subjects between 6 and 12 hours, whereas there was no increase seen in the HTG+CVD group. The HTG-CVD group also had a significantly greater increase in the VLDL+CM PL to apo B ratio (P = .038) at 3 hours than the HTG+CVD group. This diminished amount of surface lipid per VLDL particle may account for the late decrease in the HDL-D PL to apo A-I ratio seen in HTG+CVD patients. There were no other postprandial lipid or apolipoprotein differences between the two HTG groups. We conclude therefore that the major postprandial lipoprotein abnormality in these HTG+CVD patients was a failure to increase the PL content per particle in VLDL+CM, HDL-M, and HDL-D. This abnormality could prevent the usual increase in reverse cholesterol transport seen in postprandial plasma and therefore contribute to their increased incidence of CVD. The greater insulin resistance seen in these patients also appears to contribute significantly to their CVD.  相似文献   

8.
The study objective was to determine circulating levels of the appetite-controlling neuropeptides, neuropeptide Y (NPY), galanin, and leptin, in subjects with eating disorders. The study group consisted of 48 obese women aged 19 to 45 years, 15 women with anorexia nervosa aged 18 to 23 years, and 19 lean healthy women aged 18 to 42 years (control group). The obese women were divided into four groups: (A) body mass index (BMI) = 25 to 30 kg/m2, n = 9 (overweight); (B) BMI = 31 to 40 kg/m2, n = 23 (moderate obesity); (C) BMI greater than 40 kg/m2, n = 9 (severe obesity); and (D) BMI = 31 to 40 kg/m2, n = 7 (moderate obesity + non-insulin-dependent diabetes mellitus [NIDDM]). Plasma NPY, galanin, and leptin concentrations were measured in peripheral blood samples with radioimmunoassay methods. Plasma NPY levels in obese women (groups A, B, C, and D) were significantly higher as compared with the control group (P < .01, P < .001, P < .001, and P < .001, respectively). The highest plasma NPY concentrations were observed in obese women with NIDDM. Plasma galanin levels were significantly higher in groups B, C, and D (P < .001, P < .001, and P < .001, respectively). Plasma leptin concentrations were significantly higher in groups C and D as compared with the control group (P < .001 and P < .001, respectively). Plasma NPY and galanin concentrations in women with anorexia nervosa did not differ from the levels in the control group. However, plasma leptin concentrations were significantly lower in anorectic women than in the control group (P < .01). Our results indicate that inappropriate plasma concentrations of NPY, galanin, and leptin in obese women may be a consequence of their weight status, or could be one of many factors involved in the pathogenesis of obesity.  相似文献   

9.
BACKGROUND: The possibility of primary sclerosing cholangitis (PSC) recurrence after liver transplantation has been debated. The aim of this study is to examine whether recurrent PSC and chronic rejection (CR) are different expressions of the same disease process. METHODS: One hundred consecutive patients receiving 118 grafts for the diagnosis of PSC were reviewed and placed into three groups: group A, recurrent disease, as evidenced by cholangiographic and pathologic findings with radiographic arterial flow to the liver (n=18; 15.7%); group B, those who developed CR (n=15; 13.0%); and group C, all others (n=82; 71.3%). Cholangiograms and histopathologic specimens were examined in a blinded fashion. RESULTS: Demographic factors were similar, except for age, with a significantly younger age and more episodes of rejection in groups A and B (P<0.03). Group A had a higher incidence of cytomegalovirus hepatitis (P=0.008). Five-year graft survivals for A, B, and C were 64.6%, 33.3%, and 76.1%, respectively (P=0.0001), 5-year patient survivals were 76.2%, 66.7%, and 89.1%, respectively (P=0.0001), and repeat transplantation rates were 27.8%, 46.7%, and 8.5%, respectively (P=0.005). Radiographically, 90% of cholangiograms in patients with recurrent disease showed at least multiple intrahepatic strictures. Histopathologically, patients with recurrent disease and CR shared many features. CONCLUSIONS: We have described a high incidence of recurrent PSC and CR in patients who received transplants for PSC. Histopathologic analysis suggests that CR and recurrent PSC could represent a spectrum of indistinguishable disease. However, the distinct difference in clinical outcome, as evidenced by an increased repeat transplantation rate and lower graft and patient survival in the CR group, clearly suggests that they are two distinct entities that require very different treatment strategies.  相似文献   

10.
CONTEXT: Raloxifene is a selective estrogen receptor modulator that has estrogen-agonistic effects on bone and estrogen-antagonistic effects on breast and uterus. OBJECTIVE: To identify the effects of raloxifene on markers of cardiovascular risk in postmenopausal women, and to compare them with those induced by hormone replacement therapy (HRT). DESIGN: Double-blind, randomized, parallel trial. SETTING: Eight sites in the United States. PARTICIPANTS: 390 healthy postmenopausal women recruited by advertisement. INTERVENTION: Participants were randomized to receive 1 of 4 treatments: raloxifene, 60 mg/d; raloxifene, 120 mg/d; HRT (conjugated equine estrogen, 0.625 mg/d, and medroxyprogesterone acetate, 2.5 mg/d); or placebo. MAIN OUTCOME MEASURES: Change and percent change from baseline of lipid levels and coagulation parameters after 3 months and 6 months of treatment. RESULTS: At the last visit completed, compared with placebo, both dosages of raloxifene significantly lowered low-density lipoprotein cholesterol (LDL-C) by 12% (P < .001), similar to the 14% reduction with HRT (P < .001). Both dosages of raloxifene significantly lowered lipoprotein(a) by 7% to 8% (P < .001), less than the 19% decrease with HRT (P<.001). Raloxifene increased high-density lipoprotein-2 cholesterol (HDL2-C) by 15% to 17% (P < .05), less than the 33% increase with HRT (P < .001). Raloxifene did not significantly change high-density lipoprotein cholesterol (HDL-C), triglycerides, or plasminogen activator inhibitor-1 (PAI-1); whereas HRT increased HDL-C by 11% and triglycerides by 20%, and decreased PAI-1 by 29% (for all, P < .001). Raloxifene significantly lowered fibrinogen by 12% to 14% (P < .001), unlike HRT, which had no effect. Neither treatment changed fibrinopeptide A or prothrombin fragment 1 and 2. CONCLUSIONS: Raloxifene favorably alters biochemical markers of cardiovascular risk by decreasing LDL-C, fibrinogen, and lipoprotein(a), and by increasing HDL2-C without raising triglycerides. In contrast to HRT, raloxifene had no effect on HDL-C and PAI-1, and a lesser effect on HDL2-C and lipoprotein(a). Further clinical trials are necessary to determine whether these favorable biochemical effects are associated with protection against cardiovascular disease.  相似文献   

11.
S Shimoyama  N Shimizu  M Kaminishi 《Canadian Metallurgical Quarterly》1999,23(3):284-91; discussion 291-2
Recent observations and our experience that histologic types of gastric cancer related significantly to patterns of recurrence prompted us to develop intraoperative and postoperative chemotherapy based on the preoperatively diagnosed histologic types of cancer and to evaluate its effectiveness by a prospective randomized trial. This chemotherapy regimen consisted of the intraoperative administration of mitomycin C (MMC) and postoperative administration of cisplatin (80 mg/patient, day 14), and tegaful and uracil (UFT) (300-600 mg/day for 2 years). Patients with a diffuse type of cancer were randomly assigned to one of three treatment groups: no intraoperative chemotherapy and UFT 300 mg/day (P0 group, n = 16); intraoperative chemotherapy and UFT 300 mg/day (P1 group, n = 13); or UFT 600 mg/day (P2 group, n = 17). Patients with an intestinal type of cancer were randomly assigned to one of three treatment groups: H0 (n = 17), H1 (n = 12), and H2 (n = 12); each group was subjected to the same protocols as the P0, P1, and P2 groups, respectively, except for the MMC administration route. MMC (10 mg/patient) was administered intraoperatively into the intraperitoneal cavity (P1 and P2 groups) or the portal vein (H1 and H2 groups). All patients underwent curative resection. Background factors did not differ significantly among the treatment groups. The overall survival rates were progressively worsened in the order of P2, P1, and P0 or H2, H1, and H0, respectively. The survival rate of the P2 group was statistically higher than that of the P0 group (p < 0.05). The intermediate-term survival rate of the P2 group or H2 group was significantly higher than that of the P0 group (p < 0.05) or H0 group (p < 0.05), respectively. These results suggest the effectiveness of this therapy and the possible eradication of potential micrometastatic foci outside the surgical field by the direct administration of chemotherapeutic agents to the predicted recurrence site.  相似文献   

12.
Forty four patients (22 of overt hypothyroidism and 22 of subclinical hypothyroidism) and 11 controls underwent lipid profile evaluation and two dimensional echocardiography. Amongst the various parameters evaluated, mean Interventricular Septal (IVS) dimensions were significantly (p < 0.005) raised in overt hypothyroidism [IVS: end diastolic (ED) = 0.973 +/- 0.223 cm.; end systolic (ES) = 1.300 +/- 0.240 cm.] with respect to control group [IVS : ED = 0.747 +/- 0.118 cm.; ES = 1.073 +/- 0.173 cm.]. Mean Left Ventricular Posterior Wall (LVPW) thickness was also significantly (p < 0.005) raised in overt hypothyroidism [LVPW : ED = 0.944 +/- 0.200 cm.; ES = 1.350 +/- 0.243 cm.] in comparison with control group [LVPW : ED = 0.779 +/- 0.091 cm.; ES = 1.176 +/- 0.128 cm.]. Evidence of diastolic dysfunction was present in both subclinical (n = 2) and overt hypothyroidism (n = 6) while pericardial effusion was seen only in overt hypothyroidism (n = 10). Mean Serum cholesterol was significantly raised in both subclinical (192.13 +/- 47.40 mg%) (p < 0.05) and overt hypothyroidism (231.27 +/- 68.30 mg%) (p < 0.005) with respect to control group (157.63 +/- 37.69 mg%). In overt hypothyroid patients mean serum Triglyceride (235.59 +/- 137.53 mg%) (p < 0.05), LDL (126.09 +/- 54.99 mg%) (p < 0.05) and Apo-B (0.698 +/- 0.354 g/L) (p < 0.05) levels were significantly higher as compared to control group (serum triglyceride 165.45 +/- 49.15 mg%, LDL 88.72 +/- 38.75 mg%, Apo-B 0.474 +/- 0.176 g/L.  相似文献   

13.
BACKGROUND: Diffuse alveolar hemorrhage is a frequent complication of treating malignancies with high-dose chemotherapy and bone marrow transplantation and is associated with very high mortality. This disorder's association with pulmonary inflammation, its coincidence with marrow recovery, and the usefulness of corticosteroids for treating other pulmonary hemorrhage syndromes provided the rationale for this study. METHODS: We retrospectively studied 65 episodes of diffuse alveolar hemorrhage that has occurred in 63 of 603 consecutively treated patients who had undergone high-dose chemotherapy with bone marrow transplantation. Patients were divided into three groups according to the therapy they had received for diffuse alveolar hemorrhage: supportive therapy alone (n = 12); low-dose corticosteroids (30 mg or less of methylprednisolone or its equivalent; n = 10); and high-dose corticosteroids (more than 30 mg methylprednisolone or its equivalent; n = 43). The primary outcome measures were overall survival and survival to hospital discharge, occurrence of respiratory failure requiring intubation, and development of infections subsequent to the diagnosis of diffuse alveolar hemorrhage. RESULTS: Overall survival at the end of the follow-up period was significantly higher for the high-dose corticosteroid group compared with the supportive therapy group (P = 0.005); however, treatment with low-dose steroids did not increase survival over supportive therapy alone (P = 0.198). In addition, survival to discharge was significantly increased for the high-dose group compared with the other two groups combined (33% versus 9.1%, P = 0.038). Respiratory failure after the diagnosis of diffuse alveolar hemorrhage developed in only 12 of the 22 unintubated patients in the high-dose group compared with 9 of the 10 initially unintubated patients in the other two groups (P = 0.056). Although the incidence of infections was high (40%) subsequent to diffuse alveolar hemorrhage, neither high-dose nor low-dose corticosteroid treatment significantly increased the risk of infections (P > 0.4, all comparisons). CONCLUSIONS: In this study, high-dose corticosteroid therapy for diffuse alveolar hemorrhage related to bone marrow transplantation was associated with improved total survival and survival to hospital discharge, and decreased development of respiratory failure in these patients. These results suggest the therapy is beneficial, and further prospective studies are warranted to verify the effectiveness of the treatment.  相似文献   

14.
A homozygous gene deletion of the glutathione S-transferase M1 (GSTM1) locus of genomic DNA from blood spots was studied by the polymerase chain reaction in a group of French heavy smokers (n = 361), which included patients with severe chronic bronchitis (SCB; n = 87), moderate chronic bronchitis (MCB: n = 102) and hard smokers (HS) with no permanent clinical symptoms of chronic bronchitis (n = 172). The GSTM1 0/0 genotype was found in 71.3% and 65.7% of cases in SCB and MCB, respectively, compared with only 47.1% in the control HS group (P = 0.0002). This latter figure (47.1%) is consistent with the average GSTM1 deletion frequency in French Caucasians. Moreover, the results showed a significant difference in the distribution of the GSTM1 0/0 genotype for both the SCB and MCB groups against the control HS group, according to gender (SCB: P = 0.001; MCB: P = 0.005), age (SCB: P = 0.0001; MCB: P = 0.005) and smoking history (SCB: P = 0.0001; MCB: P = 0.005). Thus, individuals homozygous for the GSTM1 gene deletion, especially in the under-41 age group (SCB: P = 0.001; MSB: P = 0.04) with an average smoking history of 16-30 pack-years (SCB: P = 0.002; MSB: P = 0.01) are more prone to chronic lung diseases, such as SCB and MCB, than are GSTM1 +/+ or 0/+ subjects. Population screening of young people for the identification of GSTM1 0/0 subjects, with special emphasis on smoking habits, might be useful (1) for the early detection of individuals at high risk of lung complications caused by environmental toxins and pollutants and (2) in clinical practice, in order to prevent the development of chronic bronchitis, which is a common disease.  相似文献   

15.
OBJECTIVE: The objective of this investigation was to evaluate and compare the mechanical behaviors of distractors used for osteogenesis under various conditions by means of common engineering standards. STUDY DESIGN: Five groups of 5 synthetic mandibles were used in this study (N = 25). The first portion of the investigation compared mandibles without intervention (group A [controls]; n = 5), mandibles that had uniform osteotomies stabilized with an external distractor (group B; n = 5), and mandibles that had simulated sagittal osteotomies rigidly fixated with 3 positional screws (group C; n = 5). The second portion of the investigation compared uniform osteotomies (group B; n = 5) and uniform corticotomies (group D; n = 5) that were stabilized with the same external distractor. The last portion of the investigation compared osteotomies stabilized with an external distractor (group B; n = 5) and osteotomies stabilized with an internal distractor (group E; n = 5). Each construct was subjected to vertical loads on a mechanical testing unit. Common engineering standards, including yield load, yield displacement, maximum load, displacement at maximum load, and stiffness, were measured, recorded, and compared by means of a 1-way analysis of variance and a Scheffé multiple comparison test or independent-samples t test. The means between groups were considered significant for P < .05. A polynomial best-fit curve was calculated for the load/displacement data for each group. RESULTS: During the first portion of the investigation, no significant differences were noted between the control, rigidly fixated sagittal osteotomy, and external distractor with osteotomy groups for displacement at maximum load (P = .19). Significant differences were noted between groups for yield displacement (P = .009), yield load (P < .001), maximum load (P < .001), and stiffness (P < .007). Failures occurred in the control and rigidly fixated groups with fractures of the synthetic mandibles. Failures occurred in the external distractor group with permanent deformation or torsion of the pins. During the second portion of the experiment, no statistically significant differences were noted between the corticotomy and osteotomy groups in stiffness (P = .363), maximum load (P = .207), or yield displacement (P = .940). Statistically significant differences were noted between groups for yield load (P = .036) and displacement at maximum load (P = .010). Failures occurred in both groups with permanent deformation or torsion of the pins. During the last portion of the investigation, statistically significant differences were noted between the external distractor and internal distractor groups in yield load (P < .001), yield displacement (P < .001), maximum load (P = .001), and displacement at maximum load (P = .01); no significant differences were noted in stiffness (P = .71). Failures occurred in the external distractor group with permanent deformation or torsion of the pins. Failures occurred in the internal distractor group with fracture of the model or displacement beyond 30.0 mm. CONCLUSIONS: Different patterns of mechanical behavior were found between the control and rigidly fixated sagittal osteotomy groups and the external distractor group, between the corticotomy and osteotomy groups, and between the internal and external distractor groups.  相似文献   

16.
Altered postprandial HDL metabolism is a possible cause of defective reverse cholesterol transport and increased cardiovascular risk in diabetic patients with a normal fasting lipoprotein profile. Ten normolipidemic, normoponderal non-insulin dependent diabetes mellitus (NIDDM) patients and seven controls received a 980 kcal meal containing 78 g lipids with 100 000 IU vitamin A. Chylomicron clearance was not different, but area under the curve (AUC) for retinyl palmitate in chylimicron-free serum (remnant clearance) was greater in patients (P < 0.02). LCAT activity increased postprandially to the same extent in both groups. In control subjects, cholesteryl ester transfer protein (CETP) activity (CETA) also increased by 20% (P < 0.01 at 6 h) in parallel with a 20% decrease in HDL2-CE (r = -0.55, P = 0.009). In NIDDM patients, on the contrary, CETA which was 35% higher in the fasting state (P < 0.005), decreased postprandially yet HDL2-CE remained unchanged. Postprandial HDL3 of controls were enriched with phospholipid (PL) (30.3 +/- 2.6% at 6 h) with respect to fasting (25.6 +/- 2.5%, P < 0.01) and to NIDDM-HDL3 (25.8 +/- 1.7% at 6 h, P < 0.01). These results show that variation in plasma CETA has little impact on HDL2-CE in NIDDH subjects. They support the concept that, in controls, the combined enrichment of HDL3 with PL, increased LCAT and CETA create the conditions for stimulation of cell cholesterol efflux and CE transfer to apo B lipoproteins. In NIDDM, because of the lesser HDL3 enrichment with PL and of the inverse trend of CETA, these conditions fail to occur, depriving the patients of a potentially efficient mechanism of unesterified cholesterol (UC) clearance, despite their strictly normal preprandial profile.  相似文献   

17.
BACKGROUND: Decreased red blood cell survival contributes to the anemia of chronic renal failure patients. Because patients on chronic dialysis therapy are frequently exposed to excessive complement activation, we investigated the susceptibility of this patient population to erythrocyte C5b-9 deposition, complement-mediated lysis, and ghost formation. METHODS: We developed a flow cytometric assay using antibodies to both glycophorin and the C5b-9 complex to detect C5b-9 deposition on intact erythrocytes and erythrocyte ghosts. Serum C5b-9 levels and C5b-9 deposition on erythrocyte ghosts were measured by enzyme-linked immunosorbent assay. RESULTS: A significant increase in C5b-9 deposition on intact erythrocytes was demonstrated in patients with advanced chronic renal failure (2.2 +/- 0.5%) and in patients on chronic maintenance hemodialysis (2.3 +/- 0.4%) compared with normal volunteers (0.9 +/- 0.1%, P = 0.005 vs. chronic renal failure, P < 0.001 vs. chronic hemodialysis patients). There was also a significantly higher percentage of C5b-9-positive erythrocyte ghosts in patients with advanced chronic renal failure (20.6 +/- 5%) and in chronic hemodialysis patients (15.5 +/- 3.1%) compared with normal controls (2.6 +/- 0.9%, P < or = 0.001 vs. advanced chronic renal failure and chronic hemodialysis patients). Treatment of erythrocyte preparations with cobra venom factor, which activates the complement cascade, resulted in dramatic increases in the percentages of C5b-9-positive erythrocyte ghosts in patients with chronic renal failure (49.9 +/- 6.9%) and in chronic hemodialysis patients (45.0 +/- 4.2%) compared with normal volunteers (22.3 +/- 2.7%, P < 0.001 vs. chronic renal failure and chronic hemodialysis patients). Erythrocyte membrane expression of the complement regulatory proteins CD59 and CD55 did not significantly differ between normal controls and hemodialysis patients. Plasma C5b-9 levels after cobra venom factor stimulation were higher in chronic renal failure patients (538 micrograms/ml) compared with normal controls (345 micrograms/ml, P < 0.001). CONCLUSIONS: Patients with chronic renal failure and on hemodialysis therapy are susceptible to erythrocyte C5b-9 deposition with subsequent lysis and ghost formation. Susceptibility to complement-mediated erythrocyte injury may contribute to the anemia of chronic renal disease.  相似文献   

18.
This study examined the hypocholesterolemic effect and hormonal changes resulting from 30 d of supplementation with Vicia faba L. (field bean) flour of diets of young men (aged 18-21 y; n = 40) with borderline-high or high serum cholesterol values. All subjects (groups A-D) consumed the same basic diet. Additionally, volunteers in the control group (A) consumed 90 g control flour/d whereas those in the three bean groups received either 90 g cooked field bean flour (groups B and C) or 90 g raw field bean flour (group D) daily. Groups A and B included volunteers with borderline-high cholesterol values [5.2-6.2 mmol total cholesterol/L and 3.4-4.1 mmol low-density-lipoprotein (LDL) cholesterol/L]. Subjects in groups C and D had high serum cholesterol concentrations (total cholesterol > 6.2 mmol/L and LDL cholesterol > 4.1 mmol/L). After 30 d, serum glucose, insulin, triacylglycerol, total, LDL-cholesterol, and very-low-density-lipoprotein (VLDL)-cholesterol values were significantly lower than initial values in all subjects who consumed diets containing field bean flour (P < or = 0.0001, except for LDL-cholesterol concentrations in group C, for which P < or = 0.0007). Legume intake also resulted in a significant increase (P < or = 0.0001) in glucagon and high-density-lipoprotein cholesterol. Neither cortisol nor thyroid hormone values changed significantly. The results suggest that the hypocholesterolemic effect of field bean intake depends at least partly on a concomitant increase in glucagon and decrease in insulin values. The more marked reduction in triacylglycerol and VLDL-cholesterol concentrations in subjects who consumed raw field beans indicates a coparticipation of their thermolabile components.  相似文献   

19.
Small angle X-ray diffraction was used to examine arterial smooth muscle cell (SMC) plasma membranes isolated from control and cholesterol-fed (2%) atherosclerotic rabbits. A microsomal membrane enriched with plasma membrane obtained from animals fed cholesterol for up to 13 weeks showed a progressive elevation in the membrane unesterified (free) cholesterol:phospholipid (C/PL) mole ratio. Beyond 9 weeks of cholesterol feeding, X-ray diffraction patterns demonstrated a lateral immiscible cholesterol domain at 37 degrees C with a unit cell periodicity of 34 A coexisting within the liquid crystalline lipid bilayer. On warming, the immiscible cholesterol domain disappeared, and on cooling it reappeared, indicating that the immiscible cholesterol domain was fully reversible. These effects were reproduced in a model C/PL binary lipid system. In rabbits fed cholesterol for less than 9 weeks, lesser increases in membrane C/PL mole ratio were observed. X-ray diffraction analysis demonstrated an increase in membrane bilayer width that correlated with the C/PL mole ratio. This effect was also reproduced in a C/PL binary lipid system. Taken together, these findings demonstrate that in vivo, feeding of cholesterol causes cholesterol-phospholipid interactions in the membrane bilayer that alter bilayer structure and organization. This interaction results in an increase in bilayer width peaking at a saturating membrane cholesterol concentration, beyond which lateral phase separation occurs resulting in the formation of separate cholesterol bilayer domains. These alterations in structure and organization in SMC plasma membranes may have significance in phenotypic modulation or aortic SMC during early atherogenesis.  相似文献   

20.
Membrane microviscosity and human platelet function   总被引:2,自引:0,他引:2  
An increased sensitivity to epinephrine-induced aggregation has been observed both in platelets obtained from patients with type IIa hyperlipoproteinemia and in normal platelets following incubation with cholesterol-rich lecithin dispersions. We have reported previously that the membrane fraction of platelets is enriched with cholesterol relative to phospholipid under each of these conditions. To further explore the effect of cholesterol on platelet membranes, we have examined the fluidity (microviscosity) of whole platelets and platelet subcellular fractions using a hydrophobic fluorescent probe, 1,6-diphenyl-1,3,5-hexatriene (DPH), under conditions in which the cholesterol-to-phospholipid mole ratio (C/PL) of platelets was varied by incubation with various cholesterol-lecithin sonicated dispersions. The C/PL of platelets directly influenced the rotational diffusion of DPH, as indicated by changes in fluorescence polarization. This was reflected in an increase in microviscosity at 37 degrees C (ETA37) from 2.84 P in normal platelets to 4.06 P in platelets with a 118% increase in C/PL. Conversely, platelets with a 43% decrease in C/PL had a 13% decrease in eta37. A strong correlation (r = 0.94) existed between C/PL and eta37 throughout this entire range. However, C/PL had no effect on the excited-state fluorescence lifetime of DPH. Both C/PL and eta37 were lower in isolated platelet membranes than in the platelet granule fraction. When platelets were incubated for 20 h with cholesterol-rich dispersions, there was an increase in C/PL and eta37 in both the membrane and granule fractions. However, this occurred more rapidly in membranes so that, at 5 h (a time when an increased sensitivity of whole platelets to epinephrine is evident), membrane C/PL had increased 55% and eta37 had increased 42%, whereas granule C/PL and eta37 had changed minimally. Cholesterol-rich platelets and subcellular fractions had a lower fusion (or flow) activation energy for viscosity (deltaE), reflecting a higher degree of order, and the converse was true in cholesterol-poor platelets. Moreover, a strong negative correlation existed between the percent change in deltaE and the percent change in eta37 induced either by cholesterol incorporation or depletion. These data demonstrate that cholesterol influences the fluidity and the degree of order within the hydrophobic core of platelet membranes. Changes induced in these physical properties by an excess of cholesterol relative to phospholipid may underlie the abnormal reception or transmission of the aggregation stimulus in cholesterol-rich platelets.  相似文献   

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