Adhesion molecules and cardiovascular risk in peripheral arterial disease

Although intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) play a relevant role in atherosclerosis, little is known about the prognostic impact of their soluble forms (s) in patients with peripheral arterial disease (PAD). The aim of this prospective study was to verify whether plasma levels of s ICAM-1 and s VCAM-1 predict cardiovascular risk in PAD, and improve the prognostic value of the ankle/brachial index (ABI) alone. Accordingly, plasma levels of sICAM-1 and sVCAM-1, and the ABI were measured in 75 PAD patients who were monitored for a mean of 24±13 months. Twenty-two (29.3%) patients had a cardiovascular event (15 coronary, 3 cerebrovascular and 4 peripheral events). Plasma levels of sVCAM-1 were 618±258 ng/mL in patients with and 496±164 ng/mL in those without an event (p= 0.016). The corresponding sICAM-1 values were 344±239 ng/mL and 275±99 ng/mL (p= 0.079). The cardiovascular event rate was higher in patients with sVCAM-1 levels above the median than in those with sVCAM-1 below the median (p=0.0027 by log rank test). Independent predictors of events were sVCAM-1 levels above the median (p=0.005) and an ABI below the median (p= 0.001). Amongst patients with ABI below the median, the occurrence of sVCAM-1 above the median was associated with a 3.4-fold increase in risk (95% CI 1.308 to 9.573, p= 0.013). In conclusion, increased plasma levels of sVCAM-1 have a negative prognostic impact in PAD and improve the predictive value of ABI, which is currently the most powerful risk indicator in these patients.

High Levels of Adhesion Molecules Are Associated with Impaired Endothelium-dependent Vasodilation in Patients with Peripheral Arterial Disease

Soluble intercellular adhesion molecule-1 (sICAM-1) and vascular cellular adhesion molecule-1 (sVCAM-1) were measured alongside flow-mediated vasodilation (FMD) in 34 patients with intermittent claudication and 14 control subjects. Patients with plasma sICAM-1 >253 ng/mL (median value) showed lower FMD than those with sICAM-1 <253 ng/mL (5.6 ± 1.8% vs 9.6 ± 4.2%, p <0.01). Similarly, in the 17 patients with plasma sVCAM-1 >414 ng/mL, FMD was lower than in the remaining 17 patients (6.1 ± 1.9% vs 9.2 ± 4.5%, p <0.05). Additionally, when endothelial dysfunction was defined as FMD ≤5.5%, patients with FMD below this value had higher plasma concentrations of sICAM-1 and sVCAM-1 than those with FMD >5.5%. Therefore, our findings indicate a close association between elevated plasma levels of adhesion molecules and endothelial dysfunction. As impaired endothelial function is one of the first steps in atherogenesis, our findings have clinical relevance since they serve as the basis for further evaluation of sICAM-1 and sVCAM-1 as potential plasma markers for progression of atherosclerosis in a population at high risk.

Increased inflammatory status and higher prevalence of three-vessel coronary artery disease in patients with concomitant coronary and peripheral atherosclerosis

The aim of this study was to determine whether patients with coronary artery disease (CAD) and concomitant peripheral arterial disease (PAD) have a greater inflammatory status than those with CAD alone. To this aim, we evaluated PAD (ankle/brachial pressure index <0.9), and measured plasma levels of C-reactive protein (CRP), interleukin-6 (IL-6) and the soluble forms of intercellular adhesion molecule-1 (sICAM-1) and vascular cell adhesion molecule-1 (sVCAM-1) in 234 patients who underwent coronary angiography. Median levels of CRP, IL-6 and sICAM-1 were higher in the CAD without PAD (n=134) and CAD+PAD (n=40) groups than in 60 patients without either disease (“controls”). Median CRP values were higher in patients with CAD+PAD than in patients with CAD alone (4.7 mg/L [1.5;7.6] vs 2.4 mg/L [0.9;3.8], p < 0.01). Three-vessel CAD was diagnosed in 60% of CAD+PAD patients and in 21% (p< 0.01) of CAD only patients. After adjustment for confounding factors, only PAD was independently associated with three-vessel CAD (p<0.001). This association was maintained after adjustment for IL-6, the only inflammatory parameter significantly associated with three-vessel CAD at univariate analysis (p<0.01). In conclusion, in CAD the coexistence of PAD is associated with a greater inflammatory status and more widespread coronary atherosclerosis. These results could help to explain the high cardiovascular risk of patients with concomitant CAD and PAD and suggest that PAD be included among the variables used to identify CAD patients for further diagnostic evaluation.

Impact of diabetes on cardiac sympathetic innervation in patients with heart failure: a 123I meta-iodobenzylguanidine (123I MIBG) scintigraphic study

OBJECTIVE

Impaired parasympathetic and sympathetic nervous system activity have been demonstrated in patients with diabetes mellitus (DM) and correlated with worse prognosis. Few data are available on the effect of DM on cardiac neuropathy in heart failure (HF). The aim of the current study was to assess cardiac sympathetic activity in HF patients with and without DM.

RESEARCH DESIGN AND METHODS

Patients with severe HF (n = 75), with (n = 37) and without DM (n = 38), and 14 diabetic patients with normal cardiac function underwent (123)I meta-iodobenzylguanidine scintigraphy from which early and late heart-to-mediastinum (H/M) ratios were calculated. Clinical, echocardiographic, and biochemical data were measured.

RESULTS

DM compared with non-DM patients showed significantly lower early (1.65 ± 0.21 vs. 1.75 ± 0.21; P < 0.05) and late H/M ratios (1.46 ± 0.22 vs. 1.58 ± 0.24; P < 0.03). Early and late H/M were significantly higher in DM patients without HF (2.22 ± 0.35 and 1.99 ± 0.24, respectively) than HF patients with (P < 0.0001) and without (P < 0.0001) DM. In HF patients, an inverse correlation between early or late H/M ratio and hemoglobin A1c (HbA1c) (Pearson = -0.473, P = 0.001; Pearson = -0.382, P = 0.001, respectively) was observed. In DM, in multivariate analysis, HbA1c and ejection fraction remained significant predictors of early H/M; HbA1c remained the only significant predictor of late H/M. No correlation between early or late H/M and HbA1c was found in non-DM patients.

CONCLUSIONS

Diabetic patients with HF show lower cardiac sympathetic activity than HF patients not having DM or than DM patients with a similar degree of autonomic dysfunction not having HF. HbA1c correlated with the degree of reduction in cardiac sympathetic activity.

Are hepatic steatosis and carotid intima media thickness associated in obese patients with normal or slightly elevated gamma-glutamyl-transferase?

BACKGROUND

Hepatic steatosis (HS) has been associated with obesity and metabolic syndrome (MS), conditions carrying a high risk of coronary artery disease. We aimed to determine whether HS was an independent factor of atherogenic risk beyond its association with MS and its components.

METHODS

We assessed the circulating levels of the heat shock protein-70 (HSP-70), a chaperone involved in inflammation, endoplasmic reticulum stress and apoptosis at liver and endothelial level and the gamma-glutamyl transferase activity (γ-GT) correlating them to carotid intima-media thickness (IMT), along with lipid profile, HOMA, C-reactive protein, fibrinogen, ferritin, adiposity type as well as spleen volume in 52 obese pts with grade 1, 128 with grade 2, and 20 with grade 3 of HS evaluated by sonography.

RESULTS

Patients with different grade of HS demonstrated overlapping HSP-70 levels; similarly performed obese subjects regarding IMT. Using multiple regression analysis, IMT was predicted by age, visceral adiposity and by HOMA (β = 0.50, p < 0.0001, β = 0.30, p = 0.01 and β = 0.18, p = 0.048 respectively, while the severity of HS was predicted by visceral and subcutaneous adiposity and HOMA (β = 0.50, p < 0.0001 and β = 0.27, p = 0.001 and β = 0.18, p = 0.024, respectively).

CONCLUSION

In our series of patients with normal or mild elevation of γ-GT, the severity of HS does not entail higher IMT, which may be linked to MS stigmata.

Serum Bcl-2 concentrations in overweight-obese subjects with nonalcoholic fatty liver disease

AIM: To shed some light on the relationship between anti-apoptotic serum Bcl-2 concentrations and metabolic status, anthropometric parameters, inflammation indices, and non-alcoholic fatty liver disease severity were investigated in 43 young individuals with fatty liver (FL) and 41 with nonalcoholic steatohepatitis (NASH).

METHODS: Circulating levels of Bcl-2 were detected in 84 patients with ultrasonographic findings of “bright liver” and/or hyper-transaminasemia of unknown origin and/or increase in γ-glutamyl-transpeptidase (γ-GT) strictly in the absence of other acute or chronic liver disease, whose age was not advanced, who gave consent to liver biopsy and were then divided on the basis of the histological results into two groups (43 with FL and 41 with NASH). Twenty lean subjects, apparently healthy and young, were chosen as controls.

RESULTS: Serum Bcl-2 concentrations were significantly higher in the FL group than in the NASH group. Insulin resistance and γ-GT activity were significantly higher in NASH subjects. Apoptotic hepatocytes were significantly more numerous in NASH patients. NASH patients presented with larger spleens and augmented C-reactive protein (CRP) concentrations than healthy subjects. Steatosis grade at histology was similar in both NASH and FL populations. The number of apoptotic cells was significantly related to anti-apoptotic Bcl-2 protein values in FL patients. Bcl-2 serum levels positively correlated to body mass index (BMI) values (P≤ 0.0001) but not to age of the population. Triglycerides/HDL ratio correlated well to waist circumference in males (P = 0.0008). γ-GT activity was associated with homeostatic metabolic assessment (HOMA) (P = 0.0003) and with serum ferritin (P = 0.02). Bcl-2 concentrations were not related to either spleen size or CRP values. NASH patients presented a weak negative correlation between lobular inflammation and Bcl-2 levels. A prediction by low values of serum Bcl-2 towards a greater presence of metabolically unhealthy overweight/obese patients (MUOs) was evidenced. HOMA, BMI and uric acid, in that sequence, best predicted serum Bcl-2 concentrations.

CONCLUSION: MUOs could be detected by Bcl-2 levels. By favoring the life span of hepatocytes, and enhancing triglyceride formation, the anti-apoptotic process inhibits free fatty acids toxicity in FL.

N-terminal pro-b-type natriuretic peptide and left atrial function in patients with congestive heart failure and severely reduced ejection fraction

AIMS

Amino-terminal portion of pro-B-type natriuretic peptide (NT-pro-BNP) is a valuable diagnostic and prognostic marker in congestive heart failure (CHF). In CHF patients, elevation of natriuretic peptide levels correlate with decreased left ventricular (LV) ejection fraction (EF) and increased left atrial (LA) volumes, but a correlation with LA function that is a determinant of haemodynamic and clinical status in CHF with independent prognostic value has never been investigated. Aim of this study was to evaluate the relationship between cardiac neurohormonal activation and LA function in patients with CHF due to dilated cardiomyopathy.

METHODS AND RESULTS

One hundred and one patients (86% males; mean age, 64 ± 11 years) with dilated ischaemic or non-ischaemic cardiomyopathy, LV EF ≤45% (mean LV EF, 33 ± 8%), and New York Heart Association class II-IV underwent transthoracic echocardiography to evaluate LA fractional active and total emptying from M- and B-Mode images, and, on the same day, venous blood sample collection to dose NT-pro-BNP. By univariate analyses, NT-pro-BNP significantly correlated to age, LA dimensions, LA function indexes, EF, and functional class. At multivariate analysis, LV EF and M- or B-Mode indexes of LA function were the only independent predictors of NT-pro-BNP values. A NT-pro-BNP cut-off of 1480 pg/mL identified LA dysfunction with 89% specificity and 54% sensitivity.

CONCLUSION

In CHF patients with severely impaired systolic function, NT-pro-BNP levels reflect LA and LV dysfunction. These data should prompt studies to investigate the relationship between changes of LA function and NT-pro-BNP levels and their clinical value as prognostic and therapeutic targets in CHF.

Circulating levels of cytochrome C, gamma-glutamyl transferase, triglycerides and unconjugated bilirubin in overweight/obese patients with non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease, characterized by hepatocyte apoptosis, is distinct in fatty liver and non-alcoholic steatohepatitis, the more severe form. Apoptotic cell death is caspase-dependent and associated with mitochondrial membrane depolarization and cytochrome c release. Adhering to the hypothesis that the exposure of hepatocytes to free fatty acids, resulting in increased ROS production and mitochondrial damage, is balanced by the presence of antioxidant substances, circulating levels of gamma-glutamyl transferase, cytochrome c, triglycerides and unconjugated bilirubin were explored in patients suffering from non-alcoholic fatty liver disease with different severity. One hundred and eighty-six consecutive patients who presented recent ultrasound feature of bright liver without any liver disease of known origin were enrolled, eighty-nine of whom underwent liver biopsy. Forty-five subjects were allocated on the basis of histology in fatty liver group while 44 patients formed the group with non-alcoholic steatohepatitis. A cohort of 27 young, lean, apparently healthy individuals was selected as control group. The levels of gamma-glutamyl transferase were normal or slightly increased, while unconjugated bilirubin concentrations were elevated in all the spectra of non-alcoholic fatty liver disease. Comparing the present results with relevant findings from other studies dealing with diseases characterized by apoptosis, we did not find high circulating levels of cytochrome c in non-alcoholic fatty liver disease. What is more, our patients, categorized as suffering from simple fatty liver or from the more severe non-alcoholic steatohepatitis, had similar levels of cytochrome c and gamma-glutamyl transferase, p=0.19 and 0.11. Serum triglycerides were higher in patients with non-alcoholic fatty liver disease than in the healthy group, p=0.001. These findings likely reflect a balance between oxidative stress and anti-oxidant response rather than a lack of reliability of cytochrome c as a reliable biomarker of mitochondrial damage.

Does spleen volume play a role in patients with HCV-related chronic hepatitis?

As the lymphotropism of hepatitis C virus (HCV) has already been ascertained, and in the light of the fact that the immune defense system is an organized network composed of functionally interrelated tissues, this study was carried out to verify the possible involvement of spleen in HCV-related chronic hepatitis. In this cross-sectional study we measured spleen longitudinal diameter by ultrasound, beta2-microglobulin serum levels and splenic artery resistivity index (SARI) by Doppler in 51 patients treated with standard combined (Peg-Interferon plus Ribavirin) antiviral therapy. Thirty-three patients (17 females) completed the regimen and were compared to 31 controls (16 females). The mean basal values of spleen longitudinal diameter were higher in patients with chronic hepatitis than in controls, i.e., 116 mm (9.4) versus 102.7 mm (9.3), P = 0.0001. In the same patients a significant trend towards increased spleen longitudinal diameter was found after antiviral therapy, independently of the stage of HCV-related chronic hepatitis. The median values of the beta2-microglobulin concentrations were not significantly higher in the patients with HCV-related chronic hepatitis compared to controls, i.e., 1.3 (0.5-2.6) versus 1 (0.6-1.4), P = 0.16, although during the course of therapy they were significantly increased. SARI values of HCV-related chronic hepatitis patients were different from those of controls, but were unvaried compared to values at the end of treatment. Neither spleen measurements nor serum beta2-microglobulin levels were able to predict therapeutic response to antiviral therapy. A stimulation/expansion of lymphoid tissue was found in patients with HCV-related chronic hepatitis. Such evidence raises the question whether physicians should continue to prescribe antiviral therapy in non-responders and supports the use of a new scheme (SLD plus beta2-MG) to diagnose this ongoing, apparently reversible, but nevertheless dangerous immunologic process.

Usefulness of NT-proBNP in the assessment of patients with aortic or mitral regurgitation

BACKGROUND

Recent application of brain natriuretic peptide and N-terminal prohormone brain natriuretic peptide (NT-proBNP) in cardiac valvular disease is very promising.

AIMS

To test the usefulness of NT-proBNP in the assessment of patients with aortic or mitral regurgitation.

PATIENTS AND METHODS

Sixty-seven patients - 23 with aortic and 12 with mitral regurgitation vs. 32 controls - were examined by color Doppler echocardiography, cardiopulmonary exercise testing, Minnesota Living with Heart Failure Questionnaire (MLWHFQ) and plasma NT-proBNP assay at rest (T0) and after maximal physical exercise (T1).

RESULTS

NT-proBNP was significantly higher in patients than in controls, both at T0 (298 +/- 85 vs. 46 +/- 11 pg/ml; P < 0.01) and at T1 (366 +/- 106 vs. 50 +/- 12 pg/ml; P < 0.01). MLWHFQ score was significantly higher in patients (19 +/- 3 vs. 1 +/- 0.6; P < 0.001) with a significant inverse correlation with VO2max (r = -0.538, P < 0.001) and a direct correlation with NT-proBNP (T0: r = 0.415, P < 0.01; T1: r = 0.458, P < 0.01). NT-proBNP was inversely correlated with VO2max (T0: r = -0.444, P < 0.001; T1:r = -0.428, P < 0.001) and directly correlated with left atrial diameter (T0: r = 0.370, P < 0.01; T1: r = 0.409, P = 0.001), and left ventricular mass index (r = 0.279, P < 0.01, and r = 0.272, P < 0.01). No correlations were found between echocardiographic parameters of valvular disease severity and VO2max, NT-proBNP and MLWHFQ.

CONCLUSIONS

NT-proBNP is useful in the assessment of the cardiac functional damage secondary to mitral and aortic regurgitation.

Relationship between calcium absorption and plasma dehydroepiandrosterone sulphate (DHEAS) in healthy males

CONTEXT

Impaired gut sensitivity to 1,25-dihydroxyvitamin D (1,25(OH)(2)D), leading to reduced intestinal calcium absorption, has been reported in older men and women. While this phenomenon in postmenopausal women has been attributed to oestrogen deficiency, it is unclear whether the same observation in older men correlates with the age-related decline in androgen concentrations.

OBJECTIVE

To examine the relationship between androgens and intestinal calcium absorption in older men.

DESIGN

Cross-sectional study on 55 healthy male volunteers, divided into younger (n = 27) and older (n = 28) groups separated according to the median age of 59 years.

MAIN OUTCOME MEASURES

Calcium absorption, total and free (calculated) testosterone, dehydroepiandrosterone sulphate (DHEAS), SHBG, and 1,25(OH)(2)D, among others, were measured.

RESULTS

Calcium absorption, free testosterone and DHEAS, but not 1,25(OH)(2)D, declined significantly with age. After adjusting for age and body mass index, stepwise regression showed that 1,25(OH)(2)D and serum albumin were the only significant determinants of calcium absorption in younger men, while the sole determinant in older men was DHEAS, not testosterone. Residual deviations from the regression of calcium absorption on 1,25(OH)(2)D, reflecting the efficiency of 1,25(OH)(2)D-induced calcium absorption, was positively correlated with DHEAS (r = 0.27, P = 0.027).

CONCLUSIONS

DHEAS is an independent determinant of calcium absorption in older men, although its manner of influence is, as yet, undefined. The age-related decline of DHEAS may, partly, account for the observed 'intestinal resistance to 1,25(OH)(2)D' in older men.

Cardiac performance during exercise in patients with Fabry's disease

BACKGROUND

Fatigability and dyspnoea on effort are present in many patients with Fabry's disease. We assessed the determinants of cardiac performance during exercise in patients with Fabry's disease and preserved left ventricular ejection fraction at rest.

MATERIALS AND METHODS

Sixteen patients with Fabry's disease and 16 control subjects underwent radionuclide angiography at rest and during exercise, tissue Doppler echocardiography and magnetic resonance imaging at rest.

RESULTS

The exercise-induced change in stroke volume was +25 +/- 14% in controls and +5.8 +/- 19% in patients with Fabry's disease (P < 0.001). In 10 patients (group 1), the stroke volume increased (+19 +/- 10%), and in 6 patients (group 2) it decreased (-16 +/- 9%) with exercise. Patients of group 2 were older, had worse renal function, higher left ventricular mass and impaired diastolic function compared to group 1. The abnormal stroke volume response to exercise in group 2 was associated with a decrease in end-diastolic volume (P < 0.001) and a lack of reduction of end-systolic volume (P < 0.01) compared with both controls and group 1. The ratio of peak early-diastolic velocity from mitral filling to peak early-diastolic mitral annulus velocity was the only independent predictor of exercise-induced change in stroke volume (B -0.44; SE 0.119; beta-0.70; P < 0.005).

CONCLUSIONS

The majority of patients with Fabry's disease were able to augment stroke volume during exercise by increasing end-diastolic volume, whereas patients with more advanced cardiac involvement may experience the inability to increase cardiac output by the Frank Starling mechanism.

Enhanced serum concentrations of transforming growth factor-beta1 in simple fatty liver: is it really benign?

Background

Inside the spectrum of non-alcoholic fatty liver disease, simple fatty liver is generally thought of as being "non progressive", differently from non-alcoholic steatohepatitis, which increases in severity due to the presence of apoptosis/inflammation and fibrosis. The "benignity" of fatty liver is widely accepted but conceptually difficult to maintain because the mechanisms underlying this entity are the same ones that determine the more severe form.

Findings provide evidence that iron overload is associated with increased liver damage and collagen deposition. Transforming growth factor-beta1 released by hepatic stellate cells during chronic liver injury plays a critical role in liver apoptosis and fibrogenesis.

Objective

To verify whether both the forms of non-alcoholic fatty liver disease were really dissimilar, evaluating the serum profile of two key parameters, indexes of severity.

Methods

A total of 123 patients (57 females) participated, forming three groups: forty five patients with fatty liver, 42 patients with non-alcoholic steatohepatitis and 36 with chronic hepatitis C. All had a biopsy-proven diagnosis.

Measurements

Serum concentrations of transforming growth factor-beta1 and ferritin.

Results

High concentrations of transforming growth factor-beta1 were noticed in patients suffering from both fatty liver and non-alcoholic steatohepatitis, 129.1 (45.4) versus 116.8 (42.2) ng/mL, P = 0.2; they were significantly superior to those of chronic hepatitis C patients 87.5 (39.5) ng/mL, P < 0.001. Ferritin levels were on average above normal values and similar in the three groups (P = 0.9), also when adjusted for gender (P = 0.5) and age (P = 0.3).

Conclusion

No difference between serum concentrations of transforming growth factor-beta1 and ferritin in fatty liver and non-alcoholic steatohepatitis suggests that these forms share more common aspects, regarding their progression, than previously thought.

The contribution of omental adipose tissue to adipokine concentrations in patients with the metabolic syndrome

PURPOSE

To examine differences in peripheral vascular endothelial growth factor (VEGF), interleukin-6 (IL6) and cortisol concentrations between patients with both visceral obesity and metabolic syndrome, and lean controls. In a subsample of metabolic patients underwent abdominal surgery, the adipokine concentrations were measured in venous blood from the omentum to determine information on some processes of synthesis.

METHODS

Forty-two healthy lean controls and 46 overweight-obese patients with central adiposity and stigmata of metabolic syndrome were studied. In a subsample of 11 metabolic patients undergoing non-bariatric surgery, blood samples from omental and peripheral veins were taken intraoperatively to determine VEGF, IL6 and cortisol concentrations.

RESULTS

Median levels (range) of peripheral VEGF and IL6 were higher in patients than in controls [31.5 (3-112) pg/mL vs 21.35 (9-41.9) pg/mL (P < 0.05) and 5.50 (1.40-13) pg/mL vs 1.15 (0.3-1) pg/mL (P < 0.0001)]. On the other hand, concentrations of VEGF and IL6 from the omental and peripheral veins were similar in the surgery sub-group. Peripheral cortisol concentrations were not higher in patients than in controls, nor were omental concentrations different from the peripheral. Omental and peripheral VEGF and cortisol values were correlated, whereas no association was found between omental and peripheral IL6.

CONCLUSIONS

In the presence of abdominal obesity, VEGF and IL6 concentrations are increased in the systemic circulation. The contribution of visceral adipose tissue to circulating levels of VEGF and IL6 was modest.

Ramipril in post-renal transplant erythrocytosis

BACKGROUND

Posttransplant erythrocytosis (PTE; i.e., hematocrit [Ht] >=51%) may be responsible for cardiovascular events. Angiotensin-converting enzyme inhibitors (ACEIs) are increasingly employed in PTE treatment. Diverse ACEIs have been administered at variable doses and with erratic follow-up. In addition, guidelines recommend the administration of ACEIs as first-line therapy for PTE but do not give information on dosage. In this study the dose-response of a single ACEI was assessed, and patients were followed up for 1 year. The role of ACE gene polymorphism in both prevalence of PTE and successful response to ACEI therapy was also tested.

METHODS

At study entry, blood chemistry and ACE-gene polymorphism were measured. ACEI (ramipril) was initiated at 1.25 mg/day; if Ht was still >=51%, ramipril was increased every 6 weeks to ensuing greater dosages. Scheduled dosages were 1.25, 2.5, 5.0, 7.5 and 10 mg/day. Blood chemistry was repeated every 6 weeks. Serum erythropoietin (EPO) concentration was assayed at the start and end of the study. Follow-up was extended for 1 year.

RESULTS

PTE developed 12.6 +/- 16.0 months after transplantation in 40 out of 400 patients; 27 patients completed the study. Initial Ht was not correlated with any variable. Final Ht appeared normalized in 26 out of 27 patients. Mean dose (+/- SD) of ramipril was 4.6 +/- 3.6 mg. Mean time for correction of PTE was 135 days, and was not dependent on baseline Ht, hemoglobin or EPO. PTE relapsed in 4 patients. Prevalence of PTE and successful response to ramipril was not dependent on ACE-gene polymorphism.

CONCLUSION

Ramipril was effective in PTE; low doses normalized Ht in most patients. No clinical characteristics or biochemical variables predicted the response to ramipril. PTE may relapse; thus long-term follow-up is mandatory.

Effect of propionylcarnitine on changes in endothelial function and plasma levels of adhesion molecules induced by acute exercise in patients with intermittent claudication

In patients with intermittent claudication, treadmill exercise may cause acute deterioration of endothelial function and increase in plasma concentrations of adhesion molecules. The authors evaluated the efficacy of intravenously administered propionylcarnitine (PLC)in preventing these phenomena. Thirty-six claudicants with postexercise decrease in brachial artery flow-mediated dilation (FMD)were randomized to either placebo or PLC (600 mg as a single bolus followed by 1 mg/kg/min for 60 minutes).In the 18 patients randomized to placebo, FMD markedly decreased with exercise before (from 6.8 +/-0.4% to 4.0 +/-0.4%; p < 0.001) and after treatment (from 6.5 +/-0.4% to 4.4 +/-0.5%; p < 0.001). By contrast, in the PLC group, FMD significantly decreased with exercise before treatment (from 8.0 +/-0.7% to 4.4 +/-0.4%; p < 0.001), but not after active drug administration (from 7.1 +/-0.7% to 6.0 +/-0.6%; p = 0.067). The difference between treatments was not significant (p = 0.099; ANOVA). However, in the PLC group, the authors found that the greater the exercise-induced deterioration in endothelial function before treatment, the greater the capacity of PLC to prevent a postexercise decrease in FMD (r = -0.50, p = 0.034). Accordingly, they analyzed data in the 19 patients with a baseline exercise-induced decrease in FMD >or=45% (ie, the median FMD reduction in the entire group of 36 patients), and found that the exercise-induced FMD decrease was less after PLC than after placebo (p = 0.046, ANOVA). In the same subgroup, the exercise-induced increase in plasma concentrations of soluble vascular cell adhesion molecule-1 (sVCAM-1) was significantly higher before than after treatment in patients randomized to PLC (23.4 +/-5% vs 15.3 +/-7%, p = 0.007). In conclusion, in patients with intermittent claudication suffering from a greater endothelial derangement after treadmill, PLC administration provided a protective effect against deterioration of FMD and increase of sVCAM-1 induced by exercise.

The soluble transferrin receptor (sTfR)-ferritin index is a potential predictor of celiac disease in children with refractory iron deficiency anemia

The soluble transferrin receptor (sTfR) distinguishes iron deficiency anemia from other types of anemia. Refractory iron deficiency anemia is often the onset symptom in malabsorption-induced celiac disease. We evaluated whether sTfR levels distinguish celiac disease-associated iron deficiency anemia from iron deficiency anemia of other origin. To this aim we measured sTfR and ferritin levels and their ratio (the sTfR/ferritin index) and other hematological parameters in 42 anemic children (20 with and 22 without celiac disease) vs. 22 non-anemic children with celiac disease and 31 healthy controls (age range 4-12 years). Hemoglobin parameters, mean cell volume, and serum iron and ferritin levels were decreased to a similar extent in the anemic patients (celiac and non-celiac). The sTfR level in non-anemic celiac patients was similar to that of normal controls (1.7+/-0.35 mg/L), whereas it was significantly increased in non-celiac and celiac anemic patients (2.2+/-0.5 mg/L, p<0.05 and 2.7+/-1.2 mg/L, p<0.001, respectively). The sTfR/ferritin index was also increased more in the anemic celiac patients (mean 4.4, range 1.5-12.0) than in anemic non-celiac children (mean 2.6, range 1.4-4.0) compared with non-anemic children (mean 1.2, range 0.7-2.0). Differences were more pronounced when ferritin was <5 ng/mL. Thus, the sTfR/ferritin index may be a predictive measure in discriminating anemic patients with celiac disease from those without celiac disease.

Evaluation of the monocyte counting by two automated haematology analysers compared with flow cytometry

The aim is to determine the monocyte count performance of the Bayer Diagnostics ADVIA120 and Coulter LH 750 automated haematology analysers and the results obtained by these two instruments were compared with those provided by Becton Dickinson FACScan flow cytometer using the combination of CD45/CD14 MoAb. Linearity and imprecision were also evaluated. The linearity of both instruments was good. Coulter LH 750 showed better precision (4.3%) than ADVIA 120 (9.0%) both within and between batch. A significant correlation (r = 0.973) was found between the LH 750 and the flow cytometry method, while a modest one was observed between the latter and the ADVIA 120 (r = 0.880). When comparing the percentage of monocytes by means of one-way anova and Tukey test, it was found that the LH 750 provided the closest results in comparison with flow cytometry, with no statistical difference between the means (mean difference MO% = 0.6); however the difference was statistically different between the ADVIA 120 and flow cytometry (mean difference MO% = -4.06). These data were confirmed by Altman-Bland and Deming regression analyses.

Inflammatory status and endothelial function in asymptomatic and symptomatic peripheral arterial disease

Peripheral arterial disease (PAD) is a predictor of cardiovascular risk. However, it is unknown whether PAD severity influences inflammatory status and endothelial function, which play a major role in atherosclerosis. Accordingly, we measured brachial artery flow-mediated dilation (FMD), and plasma levels of several inflammatory markers in 15 control subjects, and 19 asymptomatic and 19 symptomatic PAD patients. Each symptomatic patient was matched to an asymptomatic patient for age, sex, risk factors, presence of cardiovascular disease, and pharmacological treatments. Asymptomatic patients had similar inflammatory profiles as controls, but lower median FMD (11.7% vs 8.5%, p < 0.01). Compared with asymptomatic patients, symptomatic patients had higher median C-reactive protein (1.5 mg/l vs 6.0 mg/l, p < 0.05) and interleukine-6 (1.5 pg/ml vs 3.5 pg/ml, p < 0.05), and lower FMD (8.5% vs 5.1%, p < 0.01). In the 38 PAD patients, the ankle/brachial pressure index correlated positively with FMD (p < 0.01), and negatively with C-reactive protein (p < 0.05), soluble intercellular adhesion molecule-1 (p < 0.05) and soluble vascular cell adhesion molecule-1 (p < 0.05). Thus, in PAD, endothelial function and inflammatory status are related to the severity of the circulatory impairment. This finding may contribute to the explanation of the increasingly poor prognosis with increased PAD severity.

Prevalence, risk factors and cardiovascular comorbidity of symptomatic peripheral arterial disease in Italy

The epidemiology of peripheral arterial disease (PAD) has been studied almost exclusively in northern European and northern American populations. We report the first survey in Italy to describe the prevalence of symptomatic PAD and clinical correlates. From the lists of seven general practitioners, all subjects aged 40-80 years (n = 4352) received a Rose Questionnaire (RQ). In those reporting pain in the leg while walking, which did not disappear while continuing to walk (n = 760), Doppler examination was performed. PAD was defined by ankle/brachial < or = 0.90, or reduced flow velocity. The prevalence of symptomatic PAD was 1.6% (2.4% in men, 0.9% in women). For each PAD patient, three controls matched for sex and age were randomly selected. At the multivariate analysis, smoking, diabetes and hypertension were significantly associated with PAD. A coexistent cardiovascular disease was found in 34% of patients and 11% of controls (P < 0.001). Only PAD was shown to be independently associated with a previous cardiovascular event. Although symptomatic, 45% of the patients were unaware of their condition. In conclusion, prevalence and cardiovascular comorbidity of symptomatic PAD in Italy seem to be lower than in other western countries. The finding that PAD was unrecognised in about 50% of affected individuals implies that a large proportion of PAD population is not given preventive therapy, so remaining at high cardiovascular risk. Thus, there is need to alert general practitioners to this topic.

Tissue Factor Binding of Activated Factor VII Triggers Smooth Muscle Cell Proliferation via Extracellular Signal–Regulated Kinase Activation

Background— Tissue factor (TF) is the main initiator of coagulation in vivo. Recently, however, a role for TF as a cell receptor involved in signal transduction has been suggested. The aim of the present study was to assess whether activated factor VII (FVIIa) binding to TF could induce smooth muscle cell (SMC) proliferation and to clarify the possible intracellular mechanism(s) responsible for this proliferation.

Methods and Results— Cell proliferation was induced by FVIIa in a dose-dependent manner, as assessed by [ 3 H]thymidine incorporation and direct cell counting, whereas no response was observed with active site–inhibited FVIIa (FVIIai), which is identical to FVIIa but is devoid of enzymatic activity. Similarly, no proliferation was observed when binding of FVIIa to TF was prevented by the monoclonal anti-TF antibody AP-1. Activation of the p44/42 mitogen-activated protein (MAP) kinase (extracellular signal–regulated kinases 1 and 2 [ERK 1/2]) pathway on binding of FVIIa to TF was demonstrated by transient ERK phosphorylation in Western blots and by suppression of proliferation with the specific MEK (MAP kinase/ERK kinase) inhibitor UO126. ERK phosphorylation was not observed with FVIIai or when cells were pretreated with AP-1.

Conclusions— These data indicate a specific effect by which binding of FVIIa to TF on the surface of SMCs induces proliferation via a coagulation-independent mechanism and possibly indicate a new link between coagulation, inflammation, and atherosclerosis.

[The fluid balance in the critically ill patient]

AIM

In the critically ill patient the hemodynamic management is essential. Usually the hemodynamic status is estimated by the measurement of the intravascular pressure or volume and by computing the fluid balance, while the change in body weight estimates the total body water. The fluid balance is computed by subtracting the fluid output to the input. Although the input (fluids, drugs, infusion.) are well known, the output are difficult to correctly compute, because they depend on several factors such as the body-room temperature, amount of humidity and may change with time. Aim of this study was to prospectively evaluate the accuracy of the fluid balance compared to the body weight measured by a dedicated mattress (Hill-Rom).

METHODS

Fifteen critically ill patients were enrolled (mean age of 63.2+/-19.7 years, body mass index of 24.9+/-3.5 kg/m2) and the measurements were computed every 8 hours. The data were analyzed by the Bland-Altman test.

RESULTS

Four-hundred and seventy-two measurements for a mean intensive care stay of 12.3.+/-7.3 days were computed. The Bland-Altamn showed a great inaccuracy, because the agreement (the difference between the 2 methods) was poor with a standard deviation of 1 840 L.

CONCLUSION

Although the fluid balance was not accurate, the only body weight without any intravascular measurement is not helpful for a correct clinical hemodynamic management of the patient.

Relation between calcium absorption and serum calcitriol in normal men: evidence for age-related intestinal resistance to calcitriol

OBJECTIVE

To obtain information on the causes of age-related bone loss in men and the concomitant decline in calcium absorption.

DESIGN

Cross-sectional study.

SETTING

Adelaide, South Australia, Australia.

SUBJECTS

A total of 95 healthy, Caucasian men (age range 27-87 y).

RESULTS

Calcium absorption declined with age (r=-0.46, P<0.0001), as did 24-h urine calcium, phosphate and creatinine (r>-0.21, P<0.05 for all); serum calcitriol and 25 hydroxyvitamin D did not change with age. Calcium absorption was related to serum calcitriol (r=0.20, P=0.05). An inverse relation between the residual deviations in calcium absorption, after allowing for its dependence on calcitriol, and age (F=5.4, P<0.005) was observed. The 24-h urinary calcium, phosphate and creatinine were all related to calcium absorption (r>0.41, P<0.0001). Forearm bone density fell with age (r=-0.45, P<0.0001) but was not related to calcium absorption, or markers of bone turnover.

CONCLUSIONS

In healthy Caucasian males (i) calcium absorption falls, but serum calcitriol does not change with age, (ii) the relation between calcium absorption and serum calcitriol changes with age, indicative of an intestinal resistance to calcitriol and (iii) calcium absorption is a significant determinant of 24-h urinary calcium excretion.

Endothelial dysfunction in peripheral arterial disease is related to increase in plasma markers of inflammation and severity of peripheral circulatory impairment but not to classic risk factors and atherosclerotic burden

OBJECTIVE

We undertook this study to evaluate in patients with peripheral arterial disease (PAD) the relationship of endothelial dysfunction, which is directly related to progression and clinical complications of atherosclerosis, with variables including classic risk factors, inflammation, severity of peripheral circulatory impairment, and atherosclerotic burden.

METHODS

This cross-sectional study included outpatients seen in an academic angiologic unit. Eighty-eight consecutive patients with PAD (ankle/brachial index [ABI] < 0.90) were studied. The control group consisted of 30 age-matched and sex-matched healthy subjects. Main outcome measures were endothelial function in the form of brachial artery flow-mediated dilation (FMD), plasma levels of C-reactive protein (CRP) and fibrinogen, severity of PAD according to ABI, and atherosclerotic burden, ie, atherosclerosis in one leg or in two or more other sites.

RESULTS

Compared with patients with FMD greater than 6.2% (ie, 5th percentile of FMD in control subjects), patients with FMD less than 6.2% had a similar prevalence of classic risk factors but higher median levels of CRP (1.6 vs 6.0 mg/L; P <.01) and fibrinogen (200 vs 374 mg/dL; P <.01). The two inflammatory markers were negatively correlated with FMD (P <.01). ABI was higher in patients with FMD greater than 6.2% than in those with worse endothelial function (0.72 +/- 0.15 vs 0.62 +/- 16; P <.01); there was no difference with respect to atherosclerotic burden. Multivariate analysis showed that the association of CRP, fibrinogen, and ABI with FMD less than 6.2% was unrelated to classic risk factors. In a second model, which included CRP, fibrinogen, and ABI, all three variables were independently related to FMD less than 6.2%.

CONCLUSION

Inflammation and severity of circulatory impairment are implicated in the pathophysiology of dysfunctional endothelium in PAD.

Increased inflammatory status and higher prevalence of three-vessel coronary artery disease in patients with concomitant coronary and peripheral atherosclerosis

The aim of this study was to determine whether patients with coronary artery disease (CAD) and concomitant peripheral arterial disease (PAD) have a greater inflammatory status than those with CAD alone. To this aim, we evaluated PAD (ankle/brachial pressure index <0.9), and measured plasma levels of C-reactive protein (CRP), interleukin-6 (IL-6) and the soluble forms of intercellular adhesion molecule-1 (sICAM-1) and vascular cell adhesion molecule-1 (sVCAM-1) in 234 patients who underwent coronary angiography. Median levels of CRP, IL-6 and sICAM-1 were higher in the CAD without PAD (n=134) and CAD+PAD (n=40) groups than in 60 patients without either disease ("controls"). Median CRP values were higher in patients with CAD+PAD than in patients with CAD alone (4.7 mg/L [1.5; 7.6] vs 2.4 mg/L [0.9; 3.8], p < 0.01).Three-vessel CAD was diagnosed in 60% of CAD+PAD patients and in 21% (p< 0.01) of CAD only patients. After adjustment for confounding factors, only PAD was independently associated with three-vessel CAD (p<0.001). This association was maintained after adjustment for IL-6, the only inflammatory parameter significantly associated with three-vessel CAD at univariate analysis (p<0.01). In conclusion, in CAD the coexistence of PAD is associated with a greater inflammatory status and more widespread coronary atherosclerosis. These results could help to explain the high cardiovascular risk of patients with concomitant CAD and PAD and suggest that PAD be included among the variables used to identify CAD patients for further diagnostic evaluation.

Association between vitamin D receptor gene polymorphisms and tubular citrate handling in calcium nephrolithiasis

OBJECTIVES

Hypocitraturia is a risk factor for calcium nephrolithiasis. 1,25(OH)2D3 influences renal citrate handling and enhances citraturia. The aim of this study was to evaluate the relationship between vitamin D receptor (VDR) allelic variant and urinary citrate excretion in recurrent stone formers (SF) patients.

DESIGN

Case-control study.

SUBJECTS

A total of 220 recurrent calcium oxalate SF patients and 114 healthy control (C) subjects were enrolled for this study. Subjects with urinary tract infections, hyperparathyroidism, cystinuria >70 micromol/24 h, gouty diathesis, renal tubular acidosis, renal failure, chronic diarrhoeal states, intake of thiazide diuretics, angiotensin-converting enzyme (ACE)-inhibitors, glucocorticoids or oestrogens were excluded. A standard constant diet was given for 7 days. The 24-h urinary citrate excretion and the active tubular reabsorption of filtered citrate (Rcit) were evaluated. Hypocitraturia was defined as a urinary citrate excretion lower than 1.7 mmol day-1. Stone formers patients and C were genotyped for BsmI and TaqI VDR alleles. Contingency table chi-square tests were used to compare genotype frequencies in hypocitraturic SF patients, normocitraturic SF and C.

RESULTS

The prevalence of hypocitraturia in SF patients was 32.7% (72 of 200). Hypocitraturia in these patients resulted from excessive Rcit of a normal load of citrate. We found a different distribution (P < 0.05) of BsmI and TaqI VDR genotypes in hypocitraturic SF patients compared with normocitraturic SF and C. In particular, the prevalence of bb and TT VDR genotypes in hypocitraturic SF was significantly higher than in normocitraturic SF and C.

CONCLUSIONS

These results point to a genetic association between BsmI and TaqI VDR polymorphisms and idiopathic hypocitraturia in calcium-oxalate recurrent SF patients.

Vitamin C prevents endothelial dysfunction induced by acute exercise in patients with intermittent claudication

In patients with intermittent claudication, exercise is associated with a marked increase in oxidative stress, likely responsible for systemic endothelial perturbation. In 31 claudicant patients, we assessed the effect of vitamin C administration on the acute changes induced by maximal and submaximal exercise in endothelium-dependent, flow-mediated dilation (FMD), and in plasma levels of thiobarbituric acid-reactive substances (TBARS) and soluble intercellular adhesion molecule-1 (sICAM-1). In 16 claudicants, maximal exercise reduced FMD (from 8.5+/-0.9 to 3.7+/-0.8%, P<0.01), and increased plasma levels of TBARS (from 1.93+/-0.06 to 2.22+/-0.1 nmol/ml, P<0.02) and of sICAM-1 (from 282+/-17 to 323+/-19 ng/ml, P<0.01). In eight of these patients, randomized to vitamin C, exercise-induced changes in FMD and biochemistry were abolished. This beneficial effect was not observed in the eight patients randomized to saline. In 15 patients, who walked until the onset of claudication pain (submaximal exercise), and in ten control subjects, who performed maximal exercise, no changes were observed with exercise. Thus, in claudicants, vitamin C prevents the acute, systemic impairment in endothelial function induced by maximal exercise. This finding provides a rationale for trials investigating antioxidant therapy and cardiovascular risk in patients with intermittent claudication.

Effect of paraformaldehyde on platelet size and on measurement of surface IgG

In many platelet assays, as in measurement of platelet-adherent IgG (PAIgG), platelets are fixed in paraformaldehyde (PFA). To better clarify the effect of PFA on platelet size and on PAIgG measurement we compared PAIgG levels in a series of 40 samples, with or without PFA fixing. We used an ELISA which was set up on unfixed platelets and gave excellent results in terms of linearity (r = 0.923), precision (mean CV = 5%) and correlation with a platelet suspension immunofluorescence test. We found PAIgG values in unfixed platelets were about 10-fold higher than in PFA-fixed (0.411 +/- 0.172 fg/platelet vs. 0.035 +/- 0.019 fg/platelet). This discrepancy could be a consequence of the smaller mean platelet volume (MPV) of washed platelets when fixed in PFA (8.0 +/- 0.8 fl as compared to 10.1 +/- 1.07). This effect of PFA could decrease the amount of binding sites for IgG exposed on the platelet membrane and hence explain the significantly lower PAIgG values observed in fixed platelets. The PAIgG measurements on unfixed platelets from 200 healthy subjects displayed a Gaussian distribution with a mean +/- SD of 0.32 +/- 0.13 fg/platelet, i.e., 1200 +/- 500 molecules/platelet.

Bone density and bone-related biochemical variables in normal men: a longitudinal study

BACKGROUND

The objective of this study was to determine the pattern of forearm bone loss and its relationship to markers of bone turnover and sex steroids in normal men. This was a longitudinal study over a median interval of 41 months. The study was conducted in Adelaide, Australia. Study participants were 123 healthy male subjects, between the ages of 20 and 83 years.

METHODS

Fat-corrected forearm bone mineral content (fcBMC), markers of bone formation (alkaline phosphatase, osteocalcin, procollagen type 1 C-terminal extension peptide) and bone resorption (collagen type I cross-linked telopeptide, hydroxyproline/creatinine, pyridinoline/creatinine, and deoxypyridinoline/creatinine), calculated serum bioavailable testosterone, and serum estradiol were measured.

RESULTS

The mean time-weighted rate of change in forearm fcBMC was -0.33% +/- 0.72 (SD) per year. Bone loss commenced after 30 years of age and increased with age (p <.001), particularly after age 70 years. There was no relationship between the rate of change in fcBMC and either markers of bone turnover or serum sex steroids.

CONCLUSIONS

In normal men, bone loss increases with age; there does not appear to be any relationship between this loss and either markers of bone turnover or levels of free androgen or estrogen.

Exercise increases soluble adhesion molecules ICAM-1 and VCAM-1 in patients with intermittent claudication

Adhesion molecules play a relevant role in the pathogenesis of vascular diseases. In 21 patients with intermittent claudication and 18 sex- and age-matched control subjects, we measured plasma levels of the circulating form of the adhesion molecules E-selectin, P-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) alongside von Willebrand factor (vWF), at rest, at maximally tolerated exercise and 5, 15 and 30 min after exercise. In controls, plasma sICAM-1 levels did not change with exercise, while in claudicants they increased from 285+/-15 to 317+/-16 ng/ml (p<0.01). Also for sVCAM-1 exercise did not modify plasma levels of sVCAM-1 in controls but increased it in claudicants from 671+/-45 to 751+/-47 ng/ml (p<0.05). Similarly, vWF did not change with exercise in controls, but increased in claudicants from 100+/-9% to 111+/-8% of value for pooled normal plasma (p<0.05). Exercise-induced changes in sICAM-1 negatively correlated with the maximal tolerated walking time, which is an index of disease severity. These findings indicate that, in claudicants, exercise is associated with increase in plasma levels of sICAM-1 and sVCAM-1.

Measurement of soluble adhesion molecules in primary Raynaud's phenomenon and in Raynaud's phenomenon secondary to connective tissue diseases

Adhesion molecules play a role in the inflammation and pathogenesis of vascular diseases. In 13 patients with primary Raynaud's phenomenon, 19 with Raynaud's phenomenon associated with connective tissue disease, and 16 control subjects, we measured plasma levels of soluble forms of intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin, and von Willebrand factor. Patients with secondary Raynaud's phenomenon had plasma levels of soluble forms of intercellular adhesion molecule- 1, vascular cell adhesion molecule-1, E-selectin, and von Willebrand factor which were significantly higher than in those with primary Raynaud's phenomenon and controls, while no difference was observed between patients with primary Raynaud's phenomenon and controls. Within the group with secondary Raynaud's phenomenon, the strongest correlations were between soluble forms of intercellular adhesion molecule-1 and both E-selectin, (r=0.67, P<0.001) and von Willebrand factor (r=0.58, P<0.01). In none of the three groups were the levels of soluble adhesion molecules and von Willebrand factor changed by exposure of hands to cold, although all patients had a definite vasospasm. In conclusion, this study indicates that primary Raynaud's phenomenon is not associated with elevation of soluble adhesion molecules and von Willebrand factor. Prospective studies are now required to investigate the role of these molecules as predictors of secondary diseases.

High levels of adhesion molecules are associated with impaired endothelium-dependent vasodilation in patients with peripheral arterial disease

Soluble intercellular adhesion molecule-1 (sICAM-1) and vascular cellular adhesion molecule-1 (sVCAM-1) were measured alongside flow-mediated vasodilation (FMD) in 34 patients with intermittent claudication and 14 control subjects. Patients with plasma sICAM-1 >253 ng/mL (median value) showed lower FMD than those with sICAM-1 < 253 ng/mL (5.6 +/- 1.8% vs 9.6 +/- 4.2%, p < 0.01). Similarly, in the 17 patients with plasma sVCAM-1 > 414 ng/mL, FMD was lower than in the remaining 17 patients (6.1 +/- 1.9% vs 9.2 +/- 4.5%, p < 0.05). Additionally, when endothelial dysfunction was defined as FMD < or = 5.5%, patients with FMD below this value had higher plasma concentrations of sICAM-1 and sVCAM-1 than those with FMD > 5.5%. Therefore, our findings indicate a close association between elevated plasma levels of adhesion molecules and endothelial dysfunction. As impaired endothelial function is one of the first steps in atherogenesis, our findings have clinical relevance since they serve as the basis for further evaluation of sICAM-1 and sVCAM-1 as potential plasma markers for progression of atherosclerosis in a population at high risk.

Circulating levels of cytokines and their site of production in patients with mild to severe chronic heart failure

BACKGROUND

Patients with chronic heart failure have elevated levels of proinflammatory cytokines; however, the mechanism for their increased expression and the site of their production are unknown.

METHODS

Twenty-two patients with heart failure, New York Heart Association functional class II to IV, underwent hemodynamic evaluation and echocardiographic study. Blood samples for cytokine evaluation were performed in the ascending aorta, coronary sinus, inferior vena cava, and hepatic vein. Levels of tumor necrosis factor-alpha (TNF-alpha), its soluble receptors sTNF-RI and sTNF-RII, interleukin-6 (IL-6), IL-6 soluble receptor, soluble gp130, interleukin-2 soluble receptor, and soluble Fas were measured with enzyme-linked immunosorbent assay kits.

RESULTS

IL-6 concentrations were higher in class IV patients than in class III patients, which in turn were higher than those in class II. TNF-alpha, sTNF-RI, and sTNF-RII were higher in class IV patients than in class III and II patients. Significant correlations were found between IL-6 concentrations and left ventricular end-systolic volume (r = 0.64; P <.001), pulmonary wedge pressure (r = 0.56; P <.01), and left ventricular ejection fraction (r = -0.56; P <.01). No correlation was found between TNF-alpha and its soluble receptors and left ventricular volumes or hemodynamic measures. Finally, no difference in cytokine concentrations was found among the different sample sites.

CONCLUSIONS

Among inflammatory cytokines, IL-6 concentrations better reflect the hemodynamic derangement in patients with heart failure. No cardiac or gut production of cytokines occurs in patients with mild to severe heart failure.

Inhibition of bone resorption by divided-dose calcium supplementation in early postmenopausal women

We have previously shown that a calcium (Ca) supplement of 1000 mg given in the evening reduces the overnight and early morning, but not the daytime, excretion of bone resorption markers in postmenopausal women within five years of the menopause. In the present study, we have looked at the effect of splitting the Ca into two doses of 500 mg each given in the morning and evening. We studied 19 healthy women (median age 53 years) who were all within 5 years of the menopause. On the 2 study days, urine was collected from 9 a.m. to 9 p.m. (day collection), and from 9 p.m. to 9 a.m. (night collection); a further fasting (spot) urine sample was obtained at 9 a.m. at the end of the night collection. The first day was a control day; on the second day the subjects ingested 500 mg Ca as the carbonate at 9 a.m. and 9 p.m. We measured pyridinoline cross-links excretion in all the samples, as well as hydroxyproline in the fasting urine. The Ca supplements lowered urinary excretion of the markers during the day (P < 0.01), had only a marginal effect during the night, but reduced excretion significantly in the fasting urine (P < 0.001). In the whole 24-hour period, the falls in resorption markers were small but comparable to those seen after the ingestion of 1 g of Ca in the evening. We conclude that the acute administration of 0.5 g Ca in the morning and evening reduced the markers of bone resorption in early postmenopausal women during the day but not during the following night, whereas the single 1 g supplement had the reverse effect. Over the 24-hour period, there was nothing to choose between the two regimes. Women at this stage in their life cycle probably require a larger Ca supplement if they are not taking estrogen.

The relation between bone density, free androgen index, and estradiol in men 60 to 70 years old

The cause of age-related bone loss in men is poorly understood. Previous studies of the relationship between bone density and serum androgens have yielded inconsistent results, perhaps partly because age is a determinant of both. Recent studies suggest that serum estrogen levels influence bone density in adult men. In order to determine whether bone mineral density (BMD) and bone turnover are associated with serum sex steroids, we investigated 37 normal men within a narrow age range (60-70 years). Bone mineral density at the forearm, hip, and spine, testosterone, sex hormone binding globulin (SHBG), free androgen index (FAI:T/SHBG), estradiol (E), free estradiol index (FEI:E/SHBG), and markers of bone formation (alkaline phosphatase, osteocalcin, procollagen type I C-terminal extension peptide) and bone resorption (hydroxyproline/creatinine [OHPr/Cr], deoxypyridinoline/creatinine [Dpd/Cr], pyridinoline/creatinine, collagen type I cross-linked telopeptide) were measured. Bone mineral density was positively related (r > 0.35, p < 0.05 at all sites) to log FAI, whereas there was no significant relationship between BMD and either serum total testosterone, serum E, or FEI. Bone density at the spine and hip were inversely related to both OHPr/Cr (r > -0.41, p < 0.05 for all sites) and Dpd/Cr (r > -0.36, p < 0.05 for all sites). OHPr/Cr (r = -0.41, p < 0.05) and Dpd/Cr (r = -0.41, p < 0.05) were both inversely related to log FAI. We conclude that BMD and bone turnover in adult men are related to plasma free androgens.

Effect of perimenopause on calcium absorption: a longitudinal study

OBJECTIVE

Cross-sectional studies suggest that the rise in calcium requirement at the menopause may be attributable, at least in part, to a fall in intestinal calcium absorption. The aim of the present study was to determine the effect of the menopause on intestinal calcium absorption and the relationship between any change in calcium absorption and serum calcitriol.

METHODS

Radiocalcium absorption and serum calcitriol were measured in 72 women aged 47.3 (standard error, SE 0.19) years who were initially premenopausal (as judged by menstrual history and serum follicle stimulating hormone (FSH)) and again 18 months later.

RESULTS

Calcium absorption fell at the second visit from 0.72 (0.029)/h to 0.64 (0.029)/h (p = 0.003). Serum calcitriol had also fallen at the second visit from 124 (4.2) pmol/l to 111 (4.0) pmol/l (p = 0.007). At that visit, serum FSH exceeded the premenopausal reference range in 11 subjects and the menstrual cycle had become irregular in 24 of them. In the 11 women with raised FSH at the second visit, radiocalcium absorption fell from 0.85/h (0.097) at baseline to 0.57/h (0.049) (p = 0.008), but only from 0.70/h (0.028) to 0.65/h (0.033) (not significant) in the remaining 61. Similarly, radiocalcium absorption fell significantly (p = 0.003) in the 24 women with irregular menses, but not in the remaining 48 who continued to menstruate regularly. These changes in calcium absorption were still significant after correction for changes in calcitriol levels.

CONCLUSION

The perimenopause is associated with a fall in calcium absorption, which is only in part attributable to a fall in calcitriol levels.

Blood pressure and metabolic changes during dietary L-arginine supplementation in humans

Dietary L-arginine supplementation has been proposed to reverse endothelial dysfunction in such diverse pathophysiologic conditions as hypercholesterolemia, coronary heart disease, and some forms of animal hypertension. In particular, chronic oral administration of L-arginine prevented the blood pressure rise induced by sodium chloride loading in salt-sensitive rats. To investigate the effects of L-arginine-rich diets on blood pressure and metabolic and coagulation parameters we performed a single-blind, controlled, crossover dietary intervention in six healthy volunteers. The subjects (aged 39+/-4 years, body mass index [BMI] 26+/-1 kg/m2, mean +/- SEM) received, in random sequence, three different isocaloric diets, each for a period of 1 week (Diet 1: control; Diet 2: L-arginine enriched by natural foods; Diet 3: identical to Diet 1 plus oral L-arginine supplement). Sodium intake was set at a constant level (about 180 mmol/day) throughout the three study periods. A blood pressure decrease was observed with both L-arginine-rich diets (Diet 2 v 1, SBP: -6.2 mm Hg [95% CI: -0.5 to -11.8], DBP: -5.0 mm Hg [-2.8 to -7.2]; Diet 3 v 1, SBP: -6.2 mm Hg [-1.8 to -10.5], DBP: -6.8 mm Hg [-3.0 to -10.6]). A slight increase in creatinine clearance (P = .07) and a fall in fasting blood glucose (P = .008) occurred after Diet 3 and, to a lesser extent, after Diet 2. Serum total cholesterol (P = .06) and triglyceride (P = .009) decreased and HDL cholesterol increased (P = .04) after Diet 2, but not after Diet 3. These results indicate that a moderate increase in L-arginine significantly lowered blood pressure and affected renal function and carbohydrate metabolism in healthy volunteers.

Evaluation of the Abbott CELL-DYN 4000 hematology analyzer

A new generation hematology analyzer, Abbott CELL-DYN 4000 (CD 4000), capable of providing 26 parameters, including fully automated reticulocyte, nucleated RBC, blast, band, and immature granulocyte, and variant lymphocyte counts, was evaluated by using the National Committee for Clinical Laboratory Standards H20-A protocol and compared with the Bayer-Technicon H-2 analyzer, which is used routinely in our laboratory. A lipid interference experiment and a sample aging study also were performed. Linearity, carryover, and precision were within the limits established by the manufacturer, and satisfactory agreement was found with the H-2 analyzer. The evaluation of leukocyte differential counts indicated an excellent correlation with the manual reference method for neutrophils and lymphocytes, a good correlation for monocytes and eosinophils, and a poor correlation for basophils in samples with low counts; for basophil counts of 2% or higher, we found an improvement of the correlation coefficient. In the lipid interference experiment, only hemoglobin determination was influenced significantly on the CD 4000, but by using a new Abbott hemoglobin reagent, the interference was eliminated. The CBC and differential counts were stable and reportable up to at least 24 hours. Intrasample viability information on leukocytes provided a quality check on each individual specimen.

Relationships between age, dehydro-epiandrosterone sulphate and plasma glucose in healthy men

BACKGROUND

dehydro-epiandrosterone sulphate (DHEAS) has been reported to ameliorate diabetes mellitus in rats.

AIM

we investigated the relationships between plasma glucose, age, serum DHEAS and weight in healthy men.

METHODS

we measured the serum DHEAS, fasting plasma glucose, plasma cortisol and body mass index in 169 subjects (mean age 46.5 years).

RESULTS

there was a significant decline in serum DHEAS with age (P < 0.0001). Multiple linear regression showed significant relationships with plasma glucose for all measured variables. Age was not a significant determinant of plasma glucose after adjusting for log serum DHEAS, body mass index and log serum cortisol.

CONCLUSIONS

a lowered serum DHEAS is paralleled by an elevated plasma glucose within the normal reference interval, and this may contribute to the rise in fasting plasma glucose which occurs with ageing.

The effects of low dose norethisterone on biochemical variables in postmenopausal women

Norethisterone 2.5 mg/day was administered to 26 postmenopausal women (aged 54-79 years) with varying degrees of osteoporosis and with a forearm bone mineral density value more than 2 SD below the young normal mean. Fasting blood and urine samples were collected and radiocalcium absorption measured at baseline and after treatment for a median period of 4 months. There were significant falls in serum calcium and its fractions, phosphate, alkaline phosphatase and cholesterol (HDL and LDL), and significant rises in serum chloride and parathyroid hormone. In the urine, there were significant falls in calcium, sodium and hydroxyproline. These changes were in close agreement with our previously reported responses to norethisterone 5 mg/day. We conclude that norethisterone in a dose of 2.5 mg/day is probably as effective as 5 mg/day in reducing bone resorption in postmenopausal women with low bone density.

European multicentre evaluation of the Super Aution SA-4220 urinalysis analyser

A multicentre evaluation of the urine test strip analyser Super Aution-4220 was carried out in six laboratories. The analytical performance of the instrument with regard to imprecision, linearity, detection limit, drift, carry-over and method comparison was studied. Using the Aution stick 8 test strip the pH, glucose, protein, ketones, bilirubin, blood, urobilinogen and leukocyte esterase were analysed. Specific gravity measurements were performed by refractive index method. Within-run and between-run imprecision determined at three levels of analyte were good. No carry-over was observed. Obtained results were linear through all the described analytical range. No significant drift was detected. Method comparison with some quantitative methods was performed and showed a good correlation with most of the analytes. The study of interferences showed minor interferences by common therapeutic drugs with the measurement of some analytes. During the assessment period of about 6 months no breakdown occurred in any laboratory. The Super Aution urine analyser appeared to be a highly automated analyser of urinary test strips. The operation was simple and the maintenance required only a few minutes a day.