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1.
PURPOSE: Extracellular free iron, or iron bound to ferritin, may promote oxidative injury and bacterial growth in airways of patients with chronic airway inflammation due to cystic fibrosis (CF) or chronic bronchitis (CB). In this study, we assessed sputum content of total iron, ferritin, and transferrin in patients with CF or CB as well as sputum from normal subjects with acute airway inflammation caused by viral upper respiratory tract infections (URTIs). METHODS: Spontaneously produced sputum was obtained from 33 subjects, including 10 subjects with CF, 18 subjects with CB (10 acute exacerbations, 8 with stable CB), and 5 subjects with URTIs (control subjects). After lysing and dilution, total iron concentrations were determined by controlled coulometry, ferritin was measured by radioimmunoassay, and transferrin was measured by enzyme-linked immunosorbent assay. RESULTS: Iron was not present in detectable amounts in control sputums, but ferritin was present (6+/-2 ng/mg protein, mean+/-SE), as was transferrin (2.37+/-0.44 microg/mg). Compared with control subjects, concentrations of iron in sputum were increased in patient groups with higher amounts in CF patients (242+/-47 ng/mg, p<0.01) than CB patients with acute exacerbations or patients with stable CB (98+/-50 and 42+/-12 ng/mg, p<0.05 for both). Ferritin content of sputum was also increased in each group, with CF patients (113+/-22 ng/mg, p<0.001) higher than CB patients (acute, 45+/-10 ng/mg; stable, 87+/-24 ng/mg; p<0.01 for both). Compared with control subjects, sputum transferrin was decreased in CF patients (1.09+/-0.40 microg/mg, p<0.05), but not CB patients. CONCLUSIONS: These findings indicate there are increased airway concentrations of total iron and ferritin-bound iron in patients with CB and, to a greater extent, in patients with CF. Particularly in CF patients who also demonstrated decreased airway concentrations of transferrin, ferritin-bound iron in airways may promote oxidative injury and enhance bacterial growth.  相似文献   

2.
To evaluate the effect of pravastatin on progression of coronary atherosclerosis in normocholesterolemic patients with coronary artery disease (CAD), 90 patients with CAD and serum cholesterol levels of 160 to 220 mg/dl were randomized into a pravastatin (10 mg/day) group (n = 45) and control group (n = 45) in a 2-year study. The proportions of patients with progression (an increase of > or = 15% in percent stenosis) and regression (a decrease of > or = 15% in percent stenosis) of coronary atherosclerosis were compared between the 2 groups. Of 90 patients, 80 (89%) had a final angiogram: the pravastatin (n = 39) and control group (n = 41). Percent changes in total cholesterol, low-density lipoprotein cholesterol, and apoprotein B levels were significantly greater in the pravastatin group than in the control group (total cholesterol -11 +/- 12% vs 3 +/- 15%, p < 0.01; low-density lipoprotein cholesterol -18 +/- 16% vs 4 +/- 21%, p < 0.01; apoprotein B -5 +/- 20% vs 6 +/- 20%, p < 0.05). The proportion of patients with progression of coronary atherosclerosis was significantly smaller in the pravastatin group than in the control group (21% vs 49%, p < 0.05). The proportion of patients with disease regression did not differ in the 2 groups (3% vs 2%, p = NS). In conclusion, this study indicates that cholesterol-lowering therapy with pravastatin can prevent the progression of coronary atherosclerosis even in normocholesterolemic patients with established CAD.  相似文献   

3.
OBJECTIVES: We sought to model an algorithm for noninvasive identification of angiographically obstructive three-vessel and/or left main disease based on conventional cardiac risk assessment and site and extent of coronary calcium determined by electron-beam computed tomography (EBCT). BACKGROUND: Such an algorithm would greatly facilitate clinical triage in symptomatic patients with no previous diagnosis of coronary artery disease (CAD). METHODS: We examined 291 patients with suspected, but not previously diagnosed, CAD who underwent coronary angiography for clinical indications. Cardiac risk factors were determined as defined by the National Cholesterol Education Program. An EBCT scan was performed in all patients, and a coronary calcium score (Agatston method) was computed. Total per-patient calcium scores and separate scores for the major coronary arteries were generated. These scores were also analyzed for localization of coronary calcium in the more distal versus proximal tomographic sections. These parameters and the risk factors were considered for the model described in the following section. RESULTS: Sixty-eight patients (23%) had angiographic three-vessel and/or left main CAD. Multiple logistic regression analysis determined male sex, presence of diabetes and left anterior descending (LAD) and circumflex (LCx) coronary calcium scores, independent from more distal calcium localization, as independent predictors for identification of three-vessel and/or left main CAD. Based on this four variable model, a simple noninvasive index (NI) was constructed as the following: loge(LAD score) + log(e)(LCx score) + 2[if diabetic] + 3[if male]. Receiver operating characteristic curve analysis for this NI yielded an area under the curve of 0.88+/-0.03 (p < 0.0001) for separating patients with, versus without, angiographic three-vessel and/or left main CAD. Various NI cutpoints demonstrated sensitivities from 87-97% and specificities from 46-74%. The NI values >14 increased the probability of angiographic three-vessel and/or left main CAD from 23% (pretest) to 65-100% (posttest), and NI values <10 increased the probability of no three-vessel and/or left main CAD from 77% (pretest) to 95-100% (posttest). CONCLUSIONS: On the basis of a simple algorithm ("noninvasive index"), EBCT calcium scanning in conjunction with risk factor analysis can rule in or rule out angiographically severe disease, i.e., three-vessel and/or left main CAD, in symptomatic patients.  相似文献   

4.
1. The effects of antihypertensive drugs on lipids may also influence their effect on coronary artery disease (CAD). However, the clinical significance of these effects and the extent to which they persist during long-term therapy is uncertain. 2. We performed a meta-analysis on 23 randomized trials published between 1988 and 1994 that compared the effects of atenolol, celiprolol (a beta-blocker with beta 2-adrenoceptor intrinsic sympathomimetic activity), enalapril, nifedipine and doxazosin on plasma cholesterol, low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), triglycerides and blood pressure (BP). 3. Predicted changes in CAD risk were calculated by incorporating the results for these parameters into the Framingham equations. 4. While there were no differences in antihypertensive efficacy between the drugs, atenolol significantly (P < 0.05) reduced HDL-C and increased total cholesterol, LDL-C and triglycerides compared with celiprolol, enalapril, doxazosin and nifedipine. 5. The magnitude of the effects on lipids was not significantly influenced by the duration of therapy (up to 3 years for atenolol and doxazosin and up to 2 years for celiprolol). 6. The improvement in Framingham equation point scores (systolic BP formula) was significantly (P < 0.05) less for atenolol (-0.54; confidence intervals (CI) -0.29-(-0.78)) than for celiprolol (-1.69; CI -0.68-2.70), doxazosin (-1.67; CI -1.11-(-2.23)), enalapril (-1.43; CI 0.23-(-3.07)) and nifedipine (-1.91; CI -1.22-(-2.59)). Similar results were obtained for the Framingham diastolic BP formula. 7. These results suggest that the adverse effects of atenolol ]on plasma lipids do not improve with prolonged therapy and are theoretically great enough to reduce its efficacy in reducing CAD by approximately two thirds compared with antihypertensive drugs that do not adversely affect plasma lipids. However it must be emphasized that these are theoretical effects. In order to determine the actual differences between these drugs on CAD end points, studies using these end points are required.  相似文献   

5.
Anaemia in pregnancy in developing countries continues to be a public health problem of significant proportion. At least 50% of the anaemia has been blamed on iron deficiency. In populations where chronic inflammation and iron deficiency anaemia coexist, the criteria to accurately define iron status are not always clear. Similarly, in pregnancy, with marked physiological changes, cut-off points for biochemical parameters need to be re-examined. In this study we examined the diagnostic accuracy of iron parameters including mean cellular volume (MCV), serum iron, transferrin, total iron binding capacity (TIBC) and its saturation, zinc protoporphyrin (ZPP), ferritin and serum transferrin receptor (TfR) for the assessment of iron status in a population of anaemic pregnant women in Malawi. Stained bone marrow aspirates were used as the standard for comparison. Results show that for the purpose of screening, serum ferritin is the best single indicator of storage iron provided a cut-off point of 30 microg/l is used. A number of other commonly used parameters of iron status were shown to have limited diagnostic accuracy. Logistic regression was used to obtain mathematical models for the prediction of bone marrow iron status using a combination of available parameters.  相似文献   

6.
BACKGROUND: Serum transferrin receptor (sTfR) is a transmembrane glycoprotein derived from erythroid precursors in the bone marrow. Its concentration provides a quantitative measure of total erythropoietic activity and an indication of functional iron deficiency. This study was conducted to investigate whether sTfR is a useful index of erythropoietic activity in chronic hemodialysis patients with poor response to maintenance recombinant human erythropoietin (rHuEPO) therapy. METHODS: Using an enzyme-linked immunosorbent assay, sTfR concentration was measured in 67 uremic patients who had been on hemodialysis for a mean of 42 months (3-242 months). rHuEPO was administered three times a week to keep the hematocrit above 30%. Hemoglobin, red blood cell indices, serum ferritin, serum total iron binding capacity and unsaturated iron binding capacity were determined. Of the 67 patients, 35 who responded favorably to rHuEPO with hematocrits above 30% were categorized as Group I and 32 who did not attain the target hematocrit were categorized as Group II. As a control group, 31 healthy subjects were also investigated. RESULTS: The serum iron, ferritin, transferrin iron saturation, dialysis efficiency and nutritional state were not different between groups of hemodialysis patients. The mean sTfR concentration was 2.1 +/- 0.6 micrograms/ml (range, 1.15-3.53 micrograms/ml) in Group I patients, compared with 1.9 +/- 0.9 micrograms/ml (range, 1.03-2.65 micrograms/ml) in Group II. The difference was not significant. In addition, the mean sTfR concentration of 1.8 +/- 0.4 micrograms/ml (range, 0.86-2.76 micrograms/ml) in the healthy controls was not significantly different from Groups I and II. CONCLUSIONS: sTfR concentration cannot be used to distinguish good from poor rHuEPO responders among chronic hemodialysis patients who have elevated serum ferritin (> 300 micrograms/l) and transferrin iron saturation (> 25%) during the course of maintenance rHuEPO therapy.  相似文献   

7.
There is increasing experimental evidence that oxidation of LDL plays a major role in the pathogenesis of coronary artery disease (CAD). However, results from clinical studies on LDL oxidation and CAD are not consistent. In most studies only single plasma factors of LDL oxidation have been determined. We studied 207 patients who underwent coronary angiography. They were divided into subjects with CAD (n = 137) and those without CAD (n = 70). We determined the susceptibility of LDL to in vitro oxidation (lag phase), potential prooxidative and antioxidative plasma factors (plasma vitamin E, LDL vitamin E, ascorbate, iron, copper, ferritin, and ceruloplasmin), and markers of in vivo LDL oxidation (autoantibodies to malondialdehyde-modified LDL, oxidized LDL, and thiobarbituric acid-reactive substances), plasma lipids and lipoproteins, smoking habits, and other coronary risk factors in both groups. The lag phase was significantly shorter in patients with CAD than in patients without CAD (101 +/- 38.6 versus 119 +/- 40.6 minutes, P < .01). There was no correlation between the lag phase and the other oxidation parameters or the coronary risk factors. In multivariate regression analyses the lag phase remained significant in all tested models. Our data suggest that a short lag phase of LDL oxidation might be an independent risk factor of CAD.  相似文献   

8.
The prevalence and clinical characteristics of hyperapobetalipoproteinemia (hyperapoB) and other phenotypes of dyslipoproteinemia were examined in 99 men (aged < or = 50 years) and 104 women (< or = 60 years) undergoing elective diagnostic coronary arteriography. HyperapoB was the most common phenotype (34%) associated with premature coronary artery disease (CAD). Only 20.2% of patients with CAD had a normal lipoprotein phenotype. The significant odds ratios for CAD were as follows: hypertriglyceridemic hyperapoB 17.45 (p < 0.0001), type IV 6.54 (p = 0.0001), type IIa 4.73 (p = 0.008), normotriglyceridemic hyperapoB 2.54 (p = 0.03) and type IIb 8.73 (p = 0.05). The strong association of hypertriglyceridemic hyperapoB with CAD reflected the multiplicative effect of increased low-density lipoprotein apolipoprotein B and endogenous hypertriglyceridemia, and was independent of the effects of age, sex, diabetes mellitus, systemic hypertension, body mass index and cigarette smoking. The ratio of apolipoprotein B to A-1 was better than those of low-density to high-density lipoprotein cholesterol and total to high-density lipoprotein cholesterol at discriminating dyslipidemic phenotypes from normal. Obesity was increased approximately 1.5 to two-fold in the hypertriglyceridemic phenotypes, diabetes was more prevalent in hypertriglyceridemic hyperapoB (6.8-fold; p < 0.001) and type IV (4.4-fold; p = 0.02), and hypertension was increased 1.5- to twofold in most dyslipidemic groups. The data indicate that hyperapoB and endogenous hypertriglyceridemia both contribute to the risk of premature CAD.  相似文献   

9.
BACKGROUND: The aim of this prospective study was to test a new protocol for iron supplementation in haemodialysis patients, as well as to assess the utility of different iron metabolism markers in common use and their 'target' values for the correction of iron deficiency. METHODS: Thirty-three of 56 chronic haemodialysis patients were selected for long-term (6 months) i.v. iron therapy at 20 mg three times per week post-dialysis based on the presence of at least one of the following iron metabolism markers: percentage of transferrin saturation (%TSAT) <20%; percentage of hypochromic erythrocytes (%HypoE) > 10% and serum ferritin (SF) <400 microg/l. Reasons for patient exclusion were active inflammatory or infectious diseases, haematological diseases, psychosis, probable iron overload (SF > or =400 microg/l) and/or acute need of blood transfusion mostly due to haemorrhage and change in renal replacement treatment. RESULTS: More than half (51.8%) of the patients of our dialysis centre proved to have some degree of iron deficiency in spite of their regular oral iron supplementation. At the start of the study the mean haemoglobin was 10.8 g/dl and increased after the 6 months of iron treatment to 12.8 g/dl (P<0.0001). The use of erythropoietin decreased from 118 units/kg/week to 84 units/kg/week. The criterion for iron supplementation with the best sensitivity/specificity relationship (100/87.9%) was ferritin <400 microg/l. Patients with ferritin < 100 [microg/l and those with ferritin between 100 microg/l and 400 microg/l had the same increase in haemoglobin but other parameters of iron metabolism were different between the two groups. CONCLUSIONS: Routine supplementation of iron in haemodialysis patients should be performed intravenously. Target ferritin values should be considered individually and the best mean haemoglobin values were achieved at 6 months with a mean ferritin of 456 microg/l (variation from to 919 microg/l). The percentage of transferrin saturation, percentage of hypochromic erythrocytes and ferritin <100 microg/l, were not considered useful parameters to monitor routine iron supplementation in haemodialysis patients. No significant adverse reactions to iron therapy were observed.  相似文献   

10.
Stepwise linear discrimination was used to analyze risk factors in 431 consecutive patients who underwent coronary angiography to determine which variables were most closely associated with coronary artery disease. Twenty-one risk factors were considered: total plasma cholesterol and triglycerides; the cholesterol and triglyceride content of high-density lipoproteins (HDL), low-density lipoproteins (LDL) and very low density lipoproteins (VLDL); and the percentage of total cholesterol and triglycerides in each fraction. Age, smoking history, family history, hypertension, diabetes mellitus and relative weight were also considered. Coronary artery disease was assessed using three standard grading scores. There were significant differences in risk factors between males and females. In males, LDL cholesterol and age were selected by multivariate analysis. In females, the ratio of HDL cholesterol to total cholesterol, as well as relative weight, family history, age and smoking were selected. The discriminating value of HDL cholesterol as the percentage of total cholesterol was significantly greater than that of HDL cholesterol itself. Despite highly significant associations between risk factors and the presence of coronary artery disease, the discrimination did not provide sufficient separation of the groups to give results that are useful diagnostically in individual patients.  相似文献   

11.
Iron deposition in the substantia nigra in Parkinson's disease has been associated with an increase in lactoferrin receptors and a reduction in ferritin concentration. This accumulation of iron in the brain may accelerate free radical formation, lipid peroxidation, and neuronal death. Remarkably, there are few data available concerning systemic iron metabolism in Parkinson's disease. We measured total iron binding capacity and circulating iron, ferritin, transferrin, and transferrin receptors; calculated transferrin saturation; and estimated dietary iron intake in patients with idiopathic Parkinson's disease and in controls. Concentrations of circulating iron, ferritin, and transferrin as well as total iron binding capacity and transferrin saturation were significantly lower in patients than controls. There were no differences in transferrin receptors or dietary intake of iron. The decrease in levels of systemic ferritin and transferrin and the total iron binding capacity parallels observations in a Parkinson's disease brain, but the reductions in serum iron concentrations and transferrin saturation do not, and were unexpected. These results suggest the existence of a defect in the systems that regulate the synthesis of the major proteins of iron metabolism in the liver as well as the brain in Parkinson's disease that may, over time, expedite entry of iron into the brain and decrease iron in the extracellular compartment.  相似文献   

12.
BACKGROUND: Chronic haemodialysis causes blood loss and iron-deficiency. This can be corrected with intravenous preparations, e.g. sodium ferric-gluconate (FeGl). In two patents complaints of hypotension and malaise during FeGl infusion coincided with high levels of serum iron and a calculated transferrin iron saturation above 100%. Iron toxicity could be the cause of these complaints. Free iron is known to aggravate the toxicity of free radicals and other reactive oxygen products that are constantly formed in the body. We compared four rates of FeGl infusion with regard to iron parameters. METHODS: 20 dialysis patients received a total of 26 infusions of FeGl. A rapid infusion of 135 mg (Protocol A (n=10)) or 62.5 mg (Protocol B (n=7)) of FeGl was given during the last 30 min of dialysis. A slow infusion of 125 mg (Protocol C (n=9)) or 62.5 mg (Protocol D (n=10)) was given during 4 or 4.5 h of dialysis. Blood was taken at regular intervals, before, during, and after dialysis for determination of serum iron, transferrin, ferritin, haematocrit, total protein, albumin, and lactate dehydrogenase (LDH). Transferrin saturation was calculated from transferrin and serum iron. RESULTS: With rapid infusion A (125 mg) the highest levels of serum iron (median 120 (range 40-159) micromol/l) and transferrin saturation (207 (84-331)%) were seen at the end of the infusion. These were significantly higher than the peak levels with B, C, and D (P相似文献   

13.
We investigated the clinical characteristics and coronary risk factors of Chinese patients with suspected coronary artery disease (CAD) having low serum concentrations of both low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC). Of 1,450 patients with suspected CAD (age range, 30-92 years; 948 men and 502 women), 760 had established CAD. The patients were divided into three groups according to lipid profile patterns. Group 1 patients (n = 138) had low LDL-C concentrations (< 100 mg/dL) and low TC concentrations (< 160 mg/dL). They were characterized by lower triglyceride concentrations, lower frequencies of high TC/high-density lipoprotein cholesterol (HDL-C) ratios (> 5) and LDL-C/HDL-C ratios (> 5), and lower frequencies of a family history of CAD and obesity. Group 3 patients (n = 610) had LDL-C concentrations of 130 mg/dL or above and TC concentrations of 200 mg/dL or above, much higher than in group 1. The prevalence of CAD was 41.3% (57/138) in group 1. 46.7% (328/702) in group 2, and 61.5% (375/610) in group 3. Groups with higher TC and LDL-C concentrations had a higher CAD prevalence. Coronary risk factors of group 1 patients appeared to be low HDL-C concentration, high TC/HDL-C ratio, advanced age, cigarette smoking, hypertension, and diabetes mellitus. Among these risk factors, HDL-C and hypertension were independent predictors of CAD. Unlike in the other two groups, hypertension was the only independent nonlipid risk factor. We conclude that in therapy or prevention of CAD, the goals should be to reduce LDL-C concentration to below 100 mg/dL and the TC concentration to below 160 mg/dL. However, other risk factors should also be considered.  相似文献   

14.
Despite the established utility of serum transferrin receptor (sTfR), serum ferritin, and the sTfR/log ferritin ratio (TfR-F Index) in the diagnosis of iron deficiency (ID) anemia, the numeric values of these parameters, which are indicative of subclinical ID, remain to be clearly defined. In this study, 65 apparently healthy nonanemic adults (22 men and 43 women) were treated with 3 months of oral iron supplementation to evaluate its effect on parameters reflecting iron status and to determine the prevalence of subclinical iron deficiency in apparently healthy adults. Significant supplementation-induced changes were observed in sTfR, ferritin, and TfR-F Index values in women, whereas in men, none of the studied parameters showed any significant change. Iron-deficient erythropoiesis (IDE) was not observed in men, but was found in 17 women (40%). Although individuals with a compromised iron status may be represented in substantial numbers in conventional reference populations, they can be readily identified using sTfR, ferritin, and TfR-F Index determinations.  相似文献   

15.
BACKGROUND AND OBJECTIVE: Iron deficiency anemia (IDA) is often associated with inflammatory disorders. The most conventional parameters of iron metabolism are therefore affected, making the evaluation of iron status difficult. Serum transferrin receptor (sTfR) levels are raised in iron deficiency but are not influenced by inflammatory changes. The aim of this study was to investigate the role of sTfR in differentiating IDA with inflammatory features. DESIGN AND METHODS: A diagnostic study of sTfR measured by immunoassay was carried out in IDA and anemia of chronic disorders (ACD). The cut-off points of sTfR and the ratio of sTfR/serum ferritin, which were obtained after comparing IDA and ACD, were applied to a group of 64 patients with mixed iron patterns (MIX) (16 with ACD and 48 with IDA). RESULTS: The best cut-off point of sTfR between IDA and ACD was 4.7 mg/L. Applying this cut-off to the MIX group, an efficiency of 87% was obtained (sensitivity 92% and specificity 81%). This level of sTfR correctly classified 53 out of 64 cases of the MIX group (83%). Using the ratio of sTfRx 100/serum ferritin, the best cut-off point was 8 (efficiency 100%), which correctly classified 62 out of 64 cases of the MIX group (97%). INTERPRETATION AND CONCLUSIONS: This study demonstrates that sTfR in conjunction with other iron parameters is very useful in iron deficiency evaluation, especially in hospital practice. Iron treatment should be considered in patients with mixed patterns of iron status, in which the diagnosis of IDA versus ACD is difficult, when the levels of sTfR exceed the cut-off point.  相似文献   

16.
Serum ferritin levels, hepatic histology and iron concentration were studied in a 'veteran' group of seven Swiss beta-thalassaemic patients after 93-99 months of treatment with the oral iron chelator deferiprone (L1), and another four patients who had received 54-82 months of L1 therapy. Despite continuous compliance, unexplained resurgence of serum ferritin levels occurred in 4/7 patients of the 'veteran' group after 4-5 years on L1. In three of these a concomitant increase of liver iron was also observed. Hepatic histology revealed significantly higher degrees of fibrosis in 6/11 hepatitis C (HC)-positive patients (fibrosis scores 1-5, mean 3.0) than in the HC-negative group (fibrosis score 0-2, mean 0.8). Two HC-negative patients had no detectable fibrosis after 98 and 93 months on deferiprone. Therefore the hepatic pathology in these patients cannot definitely be attributed as a side-effect of deferiprone. Chronic active hepatitis C and the accumulation of iron are the major causative factors to be considered.  相似文献   

17.
In most eukaryotic cells, synthesis of the iron storage protein, ferritin is regulated by iron levels and redox conditions. Proper iron storage is important to protect against damaging iron-catalysed free radical reactions. Although iron-catalysed reactions are believed to contribute to oxidative damage and cataractogenesis, little is known about iron storage in the lens. In this study, ferritin concentration was measured in cultured canine lens epithelial cells. Baseline ferritin concentration ranged from 76-163 ng (mg protein)-1; cells cultured in low-iron media had significantly lower ferritin levels than cells cultured in iron-supplemented media. Addition of a large excess of iron as hemin resulted in an eight-fold increase in ferritin concentration. The iron chelator, Desferal, significantly decreased ferritin concentration. The reducing agent dithiothreitol decreased the hemin-induced increase in ferritin levels, but not baseline levels. In contrast, ascorbic acid induced a large increase in ferritin content. Other studies have shown that induction of ferritin synthesis can protect against oxidative damage. Regulation of ferritin levels may represent a mechanism by which the lens epithelium is protected from oxidative damage. In vivo, epithelial cells are normally exposed to much lower iron concentrations than the cultured lens epithelial cells in this study. However, in pathological circumstances, the iron content and redox state of the aqueous humor is dramatically altered and may affect the steady state levels of ferritin within the lens. This remains to be determined.  相似文献   

18.
BACKGROUND: Patients with coronary artery disease (CAD) associated with peripheral (PAD) or cerebrovascular disease (CVD), a condition called diffuse atherosclerosis, have a higher risk of death than patients with isolated CAD. The prevalence of diffuse atherosclerosis and the atherogenic risk factors associated with this condition in our geographic area have not been described previously. METHODS: A cohort of 2597 patients (62 +/- 10.8 years, 665 women) consecutively admitted at Bellvitge Hospital because of acute coronary syndromes were studied. CAD patients were divided in two groups with diffuse and located atherosclerosis according to whether they had or they had not an associated PAD or CVD. Baseline history, physical data and lipid profile were recorded in each patient according to a standardized questionnaire. RESULTS: A total of 370 patients (14.2%) had diffuse atherosclerosis. Among them, there were more men and women older than 55 years than among those with isolated CAD. Patients with diffuse atherosclerosis were more frequently hypertensive, diabetic and former smokers than those with isolated CAD (60.5% vs. 49.4%, P < 0.01; 37.4% vs. 24.5%, P < 0.01; and 47% vs. 35.7%, P < 0.01, respectively). There were no significant differences in the mean values of total cholesterol (TC), low-density cholesterol (LDL-C), high-density cholesterol (HDL-C) and triglycerides between both groups of patients, but patients with diffuse atherosclerosis had a lower HDL-C/TC ratio, with borderline statistical significance (0.18 +/- 0.06 vs. 0.19 +/- 0.06, P = 0.06). Using multiple logistic regression analysis, the variables associated with diffuse atherosclerosis in men were age greater than 55 years (OR 1.97, CI 1.33-2.93), hypertension (OR 1.50, CI 1.14-2.20), diabetes (OR 1.78, CI 1.20-2.70), smoking (former smokers) (OR 2.09, CI 1.36-3.24) and HDL-C/TC < 0.20 (OR 1.60, CI 1.18-2.17); and in women hypertension (OR 3.43, CI 1.48-7.94) and diabetes (OR 2.58, CI 1.55-4.80). CONCLUSIONS: Clinically overt diffuse atherosclerosis is a relatively common disease. Older patients and those with hypertension, diabetes or low HDL-C/TC ratio are more likely to have diffuse atherosclerosis than those without these conditions.  相似文献   

19.
INTRODUCTION: Iron deficiency is commonly encountered in haemodialysis (HD) patients and may be overcome by i.v. iron therapy. We have examined the percentage hypochromic red cells (%HRC) for predicting response to i.v. iron in subjects with a low serum ferritin. METHODS: Prospective study of i.v. iron saccharate (trivalent iron 200 mg/week for 8 weeks) in anaemic (Hb < 10 g/dl) HD patients with serum ferritin < 100 microg/l despite oral iron therapy. Response to i.v. iron was assessed by comparing Hb at 0 and 8 weeks according to %HRC at baseline (0-3%, 4-9%, > or = 10%). Results are mean+/-1 SD. RESULTS: For all subjects (n=82), Hb and ferritin increased between 0 and 8 weeks (8.9+/-1.0 to 10.1+/-1.4, P<0.0001; 55+/-24 to 288+/-126, P<0.0001). Patients were stratified into three groups according to %HRC at baseline (0-3%, 4-9%, > or = 10%). Hb increased significantly in all three groups. The mean increase in Hb was greater (0-3%, 0.6+/-1.2; 4-9%, 1.2+/-1.0; > or = 10%, 1.6+/-1.4; P=0.02) and the proportion of patients showing a > or = 1 g/dl increase in Hb was greater (0-3%, 27%; 4-9%, 57%; > or = 10%, 67%; P=0.02) in those with the largest %HRC pre-treatment. CONCLUSION: Intravenous iron therapy is effective in improving Hb in anaemic HD patients with a low ferritin. However, the magnitude of this response and the proportion of patients responding is related to the percentage hypochromic red cells prior to treatment.  相似文献   

20.
OBJECTIVES: This study sought to examine whether lipoprotein(a) levels predict coronary artery lumen changes in patients with symptomatic coronary artery disease (CAD) and normal to moderate hypercholesterolemia. BACKGROUND: Recent conflicting reports have confirmed or refuted the association of lipoprotein(a) with clinical events or angiographically verified disease progression. METHODS: The association between serum lipoprotein(a) and changes in coronary artery lumen was studied in 704 men entered into the Regression Growth Evaluation Statin Study (REGRESS), a double-blind, placebo-controlled, quantitative angiographic study that assessed the effect of 2 years of pravastatin treatment. The primary end points were changes in average mean segment diameter (MSD) and average minimal obstruction diameter (MOD). Pravastatin- and placebo-treated patients were classified as having progressing, regressing or stable CAD, and median lipoprotein(a) concentrations were compared. Bivariate and multivariate regression analyses were performed in the overall patient group and in high risk subgroups. RESULTS: Pravastatin treatment did not affect serum apolipoprotein(a) levels. Median in-trial (sampled at 24 months) apolipoprotein(a) levels for regressing, stable and progressing CAD were, respectively, 130, 162 and 251 U/liter in placebo-treated patients and 143, 224 and 306 U/liter in pravastatin-treated patients. Predictors of MSD and MOD changes were baseline MSD and MOD, in-trial apolipoprotein(a), in-trial high density lipoprotein (HDL) cholesterol and baseline use of long-acting nitrates. The multivariate models predicted 14% of MSD changes and 12% of MOD changes; apolipoprotein(a) predicted only 2.6% and 4.8%, respectively. However, in patients with in-trial HDL cholesterol levels <0.7 mmol/liter, apolipoprotein(a) predicted up to 37% of the arteriographic changes. CONCLUSIONS: Serum lipoprotein(a) levels predict coronary artery lumen changes in normal to moderately hypercholesterolemic white men with CAD; its atherogenicity is marked in the presence of concomitant hypoalphalipoproteinemia.  相似文献   

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