Publications (19)81.45 Total impact
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Article: The effectiveness of teriparatide in the clinical practice-attenuation of the bone mineral density outcome by increasing age and bisphosphonate pretreatment.
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ABSTRACT: Background. Teriparatide is a potent anabolic agent for severe osteoporosis. Objectives. A primary objective of this retrospective study was to define the efficacy of teriparatide in terms of bone mineral density (BMD) changes and relief of back pain in clinical practice. Methods. The patient population comprises 119 osteoporotic patients treated with teriparatide for median 539 (range 179-926) days. Results. The mean BMD gain was 0.9% in the total hip (P = 0.0075), 2.1% in the femoral neck (P = 0.0006), and 8.5% in the lumbar spine (P = 0.0085). In the whole patient population age associated inversely with BMD changes in the total hip (P = 0.019) and in the femoral neck (P = 0.0036). A history of significant bisphosphonate pretreatment (n = 90) reduced BMD response in the total hip (P = 0.039). The total exposure of any prior bisphosphonate was negatively correlated with BMD response in the total hip (P = 0.0421). Half of the patients reported relief of back pain during the treatment. Leg pain, nausea, and dizziness were most frequent adverse concerns. Conclusions. Teriparatide works in clinical practice as well as in clinical trials. Younger subjects benefited more than older patients from teriparatide in the total hip and in the femoral neck. Bisphosphonate pretreatment attenuated teriparatide-induced BMD gain.Annals of medicine 01/2013; · 3.52 Impact Factor -
Article: Increased B-type natriuretic Peptide concentration is associated with reduced coronary vasoreactivity in patients with dilated cardiomyopathy but not in healthy young subjects.
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ABSTRACT: Background/Aims. Natriuretic peptides are associated with the cardiovascular disease risk under a range of different circumstances. However, less is known about whether this association is found also in young healthy subjects. Methods. 9 patients with dilated cardiomyopathy and 26 healthy young subjects were studied. The myocardial blood flow measurements were performed basally and during adenosine infusion using PET. Results. S-proBNP concentrations were significantly higher (2153 ± 1964 versus 28 ± 17 ng/L, P = .000002) and adenosine-stimulated flow lower (1.6 ± 0.8 versus 3.6 ± 1.1 mL·g(-1)·min(-1), P = .00001) in patients with dilated cardiomyopathy when compared to healthy subjects. S-proBNP concentration was inversely associated with adenosine stimulated flow in patients with dilated cardiomyopathy (r = -0.75, P = .019) but not in healthy subjects (r = -0.06, P = .84). Conclusions. Natriuretic peptides are inversely associated with coronary vasoreactivity in patients with dilated cardiomyopathy but not in healthy young subjects. Since reduced coronary vasoreactivity seems to be one of the earliest abnormalities in the development of coronary artery disease, this might indicate that natriuretic peptides are not predictor of cardiovascular disease risk in healthy young subjects.ISRN cardiology. 01/2011; 2011:638764. -
Article: The incidence of osteopenia and osteoporosis in women with hip osteoarthritis scheduled for cementless total joint replacement.
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ABSTRACT: The co-existence of osteoporosis (OP) and osteoarthritis (OA) remains obscure. No systematic studies have been carried out to exclude the possibility that especially female osteoarthritic patients selected for cementless total hip arthroplasty (THA) suffer from primary or secondary OP. A subgroup of fifty-three female patients (average age, 64.7 years) with advanced primary hip OA scheduled for cementless THA were recruited for DXA and laboratory screening. Before surgery, bone mineral density (BMD) of the lumbar spine, the proximal femurs and the distal forearm were measured. The serum concentrations of calcium, 25-hydroxyvitamin D, parathyroid hormone and biochemical markers of bone resorption and formation were determined to exclude secondary OP. The prevalence of OP (T score <-2.5) and osteopenia (-1.0 >T score >-2.5) were 28% and 45%, respectively. Statistically, OP was related to patient's age, low BMI, postmenopausal status and not having estrogen replacement therapy. Five patients (9%) had laboratory findings of secondary OP. Two of them were found to have a parathyroid adenoma. The prevalence of vitamin D insufficiency [S-25(OH)D levels <or=50 nmol/l] was 36% (n=19). As a sign of high bone turnover, the patients with reduced BMD values showed significantly increased serum levels of osteocalcin (p=0.049), intact procollagen type I N propeptide (p=0.040) and N-terminal crosslinking telopeptide of type I collagen (p=0.046). The BMC of the femoral necks of the osteoarthritic hips were significantly higher (p<0.001) and the BMC of the trochanter regions significantly lower (p=0.005) compared to the contralateral hips. Against a general belief, OA does not seem to protect a patient from generalized primary OP. The majority (74%) of the female hip OA patients were osteopenic or osteoporotic with signs of increased bone turnover. The observed prevalence of reduced BMD corresponds with the published data of age-matched population. An unexpectedly high number of patients required preoperative consultation with an endocrinologist. The altered distribution of BMD observed in the proximal femurs may explain the lower prevalence of fractures reported in the femoral necks of osteoarthritic hips.Bone 05/2007; 40(4):1041-7. · 4.02 Impact Factor -
Article: Positive family history of coronary artery disease is associated with reduced myocardial vasoreactivity in healthy men.
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ABSTRACT: Positive family history as a risk factor for coronary artery disease seems to be most important in subjects who otherwise are at low risk. We examined the association between family history of coronary artery disease and myocardial vasoreactivity in healthy men. 35 non-smoking healthy men (age 35+/-7 years) were studied: 16 had positive family history of coronary artery disease and 19 had negative family history. The myocardial blood flow measurements were performed basally and during adenosine infusion (140 mug/kg/min) with and without simultaneous physiological hyperinsulinemia (insulin infusion at a rate of 1 mU/kg/min) using positron emission tomography and O-15-water. Basal myocardial blood flow was similar between the subjects with positive and negative family history of coronary artery disease (0.79+/-0.19 and 0.79+/-0.21 mL g(-1) min(-1), NS). Adenosine stimulated flow was significantly reduced in subjects with positive family history (3.0+/-0.5 vs 4.0+/-1.2 mL g(-1) min(-1), respectively, p=0.003). During physiological hyperinsulinemia adenosine stimulated flow was further enhanced in both groups but significantly blunted in subjects with positive family history (3.7+/-0.9 vs 5.2+/-1.5 mL g(-1) min(-1), respectively, p=0.001). These differences remained significant after simultaneous controlling for age, BMI, HbA1c, LDL-cholesterol, HDL-cholesterol and blood pressure (p=0.002). Healthy non-smoking men with positive family history of coronary artery disease are characterized by impaired myocardial vasoreactivity.International journal of cardiology 11/2006; 112(3):289-94. · 7.08 Impact Factor -
Article: The influence of hepatic lipase C-480T polymorphism on coronary flow reserve in young men is independent of the plasma cholesterol level.
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ABSTRACT: The hepatic lipase (HL) gene C-480T promoter polymorphism affects gene transcription and enzyme activity and leads to CC, CT, and TT genotypes. Recently, HL expression was detected in macrophages. It has been postulated that HL might have a direct role in the pathogenesis of atherosclerosis without changes in the plasma profile. We hypothesized that the difference of plasma cholesterol level may not influence the effect of HL genotype on coronary reactivity. A total of 108 young men (aged 34+/-5 years) were genotyped and divided into three groups. These groups contained 45, 49 and 14 men having either normal (4.9+/-1.2 mmol/L), mildly (5.5+/-0.8 mmol/L) or severely (7.8+/-1.9 mmol/L, subjects with familial hypercholesterolemia) elevated mean plasma cholesterol level, respectively. Myocardial blood flow (MBF) was measured at rest and during adenosine or dipyridamole-induced hyperemia with positron emission tomography using [(15)O] H(2)O. The effect of HL genotype on the indices of MBF was parallel within all cholesterol groups and therefore they were combined. In all subjects, basal flow did not differ between the genotypes. However, men with CC genotype had a significantly higher hyperemic blood flow (3.86+/-1.26 mLg(-1)min(-1) versus 3.20+/-1.38 mLg(-1)min(-1), p=0.007), higher coronary flow reserve (CFR, 4.80+/-1.77 versus 3.77+/-1.43, p=0.001) and lower coronary resistance during hyperemia (25.63+/-9.98 mmHg min g mL(-1) versus 35.00+/-23.95 mmHg min g mL(-1), p=0.003) than T allele carriers. In multivariate regression analysis, after adjustment for age, body mass index, serum lipids, blood pressure, adenosine or dipyridamole administration, and study group, HL polymorphism was an independent predictor of blood flow during hyperemia (p=0.016), coronary resistance (p=0.014), and CFR (p=0.005), respectively. The HL C-480 T polymorphism is associated with CFR, which is an early indicator of atherosclerosis, independently of the level of plasma cholesterol in young men.Atherosclerosis 11/2006; 188(2):391-7. · 3.79 Impact Factor -
Article: A nationwide survey of mortality in acromegaly.
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ABSTRACT: Increased mortality in acromegaly has been confined to those with posttreatment basal GH of 2.5 microg/liter or greater, but the impact of IGF-I and pituitary radiotherapy on mortality has remained controversial. The purpose of this nationwide survey was to examine the all-cause mortality of patients with acromegaly and evaluate the impact of treatment outcome and mode of treatment on survival. All-cause mortality of all patients with acromegaly diagnosed during January 1980 and December 1999 in the five university hospitals of Finland was followed up by the end of 2002 (12.5 +/- 5.6 yr) and compared with that of the general population by using age- and gender-adjusted standardized mortality ratios (SMRs). Logistic regression analysis was used to investigate factors related to mortality within the survey population. Mortality was the main outcome measure. Of the 334 patients, 56 (16.8%) had died during follow-up. SMR of the patients was 1.16 [confidence interval (CI) 0.85-1.54, not significant (NS)]. However, patients with basal serum GH concentration 2.5 microg/liter or greater (SMR 1.63, CI 1.10-2.35, P < 0.001) measured 5.2 +/- 4.4 yr after the initial treatment, and those irradiated (SMR 1.69, CI 1.05-2.58, P < 0.001) showed excess mortality. In a multivariate model, the effect of radiotherapy was of borderline significance only (P = 0.083). Posttreatment IGF-I levels, available for 72.2% of the patients, did not have impact on mortality. The posttreatment basal GH concentration less than 2.5 microg/liter in acromegalic patients is associated with a normal lifespan. Excess mortality is confined to poorly controlled patients and possibly those who have received conventional radiotherapy.Journal of Clinical Endocrinology & Metabolism 08/2005; 90(7):4081-6. · 6.50 Impact Factor -
Article: Increased lipoprotein(a) is associated with reduced myocardial vasoreactivity in young healthy men.
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ABSTRACT: We examined the association between lipoprotein(a) and myocardial vasoreactivity in healthy men. Thirty non-smoking healthy men (age 34+/-6 years) were studied: 9 had increased lipoprotein(a) (>200 mg/L) concentrations (lipoprotein(a) 317 (range 218-550) mg/L) and 21 had normal lipoprotein(a) (<200 mg/L) concentrations (lipoprotein(a) 57 (range 13-156) mg/L). The myocardial blood flow measurements were performed basally and during adenosine infusion (140 microg/kg/min) with or without simultaneous physiological hyperinsulinemia (insulin infusion at a rate of 1 mU/kg/min) using positron emission tomography and [(15)O]H(2)O. Basal myocardial blood flow was similar between the subjects with increased and normal lipoprotein(a) (0.76+/-0.20 and 0.79+/-0.20 mLg(-1) min(-1), NS). Adenosine-stimulated flow tended to be reduced in subjects with increased lipoprotein(a) (3.1+/-0.7 mLg(-1) min(-1) versus 3.7+/-1.1 mLg(-1) min(-1), respectively, p=0.1). During physiological hyperinsulinemia adenosine-stimulated flow was further enhanced in both groups but significantly blunted in subjects with increased lipoprotein(a) (3.7+/-0.8 mLg(-1) min(-1) versus 4.8+/-1.4 mLg(-1) min(-1), respectively, p=0.03). This difference remained significant after simultaneous controlling for BMI, HbA1c, LDL-cholesterol, HDL-cholesterol and blood pressure (p=0.04). Already young healthy men with lipoprotein(a) concentrations greater than 200mg/L are characterized by impaired myocardial vasoreactivity.Atherosclerosis 03/2005; 179(1):185-91. · 3.79 Impact Factor -
Article: [Weakened glucose balance and numb hands].
Duodecim; lääketieteellinen aikakauskirja 02/2005; 121(20):2223, 2225-6. -
Article: Myocardial perfusion after marathon running.
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ABSTRACT: We investigated the effects of acute prolonged exercise (marathon running) on cardiac function and myocardial perfusion. Cardiac dimensions and function were measured in seven endurance-trained men using echocardiography before and repeatedly after marathon (42.2 km) running (at 10 min, 150 min, and 20 h). Myocardial perfusion and perfusion resistance were measured using positron emission tomography and 15O-H2O before and 85-115 min after running. Echocardiographic indices showed only mild and clinically non-significant changes in cardiac function after running. Rate-pressure-corrected basal myocardial perfusion (0.89+/-0.13 vs. 1.20+/-0.32 mL min(-1) g(-1), P=0.04) was increased after running. Also, adenosine-stimulated perfusion tended to be higher (3.67+/-0.81 vs. 4.47+/-0.52 mL min(-1) g(-1), P=0.12) and perfusion resistance during adenosine stimulation was significantly lower after running (26+/-6 vs. 18+/-3 mmHg min g mL(-1), P=0.03). Plasma free fatty acid (FFA) concentration was significantly increased after running. These results show that marathon running does not cause marked changes in cardiac function in healthy men. Basal perfusion was increased after exercise, probably reflecting changes in fuel preferences to increased use of FFAs. Strenuous exercise also seems to enhance coronary reactivity, which could thereby serve as a protective mechanism to vascular events after exercise.Scandinavian Journal of Medicine and Science in Sports 09/2004; 14(4):208-14. · 2.87 Impact Factor -
Article: [Non-islet cell tumor hypoglycemia].
Duodecim; lääketieteellinen aikakauskirja 02/2004; 120(22):2689-92. -
Article: Insulin- and exercise-stimulated skeletal muscle blood flow and glucose uptake in obese men.
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ABSTRACT: Insulin resistance in obese subjects results in the impaired use of glucose by insulin-sensitive tissues, e.g., skeletal muscle. In the present study, we determined whether insulin resistance in obesity is associated with an impaired ability of exercise to stimulate muscle blood flow, oxygen delivery, or glucose uptake. Nine obese (body mass index = 36 +/- 2 kg/m(2)) and 11 age-matched nonobese men (body mass index = 22 +/- 1 kg/m(2)) performed one-legged isometric exercise during hyperinsulinemia. Rates of femoral muscle blood flow, oxygen consumption, and glucose uptake were measured simultaneously in both legs using [(15)O]H(2)O, [(15)O]O(2), [(18)F]fluoro-deoxy-glucose, and positron emission tomography. The obese subjects exhibited resistance to insulin stimulation of glucose uptake in resting muscle, regardless of whether glucose uptake was expressed per kilogram of femoral muscle mass (p = 0.001) or per the total mass of quadriceps femoris muscle. At similar workloads, oxygen consumption, blood flow, and glucose uptake were lower in the obese than the nonobese subjects when expressed per kilogram of muscle, but similar when expressed per quadriceps femoris muscle mass. We conclude that obesity is characterized by insulin resistance of glucose uptake in resting skeletal muscle regardless of how glucose uptake is expressed. When compared with nonobese individuals at similar absolute workloads and under identical hyperinsulinemic conditions, the ability of exercise to increase muscle oxygen uptake, blood flow, and glucose uptake per muscle mass is blunted in obese insulin-resistant subjects. However, these defects are compensated for by an increase in muscle mass.Obesity research 03/2003; 11(2):257-65. · 4.95 Impact Factor -
Article: Insulin- and Exercise-Stimulated Skeletal Muscle Blood Flow and Glucose Uptake in Obese Men
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ABSTRACT: Objective: Insulin resistance in obese subjects results in the impaired use of glucose by insulin-sensitive tissues, e.g., skeletal muscle. In the present study, we determined whether insulin resistance in obesity is associated with an impaired ability of exercise to stimulate muscle blood flow, oxygen delivery, or glucose uptake.Research Methods and Procedures: Nine obese (body mass index = 36 2 kg/m2) and 11 age-matched nonobese men (body mass index = 22 1 kg/m2) performed one-legged isometric exercise during hyperinsulinemia. Rates of femoral muscle blood flow, oxygen consumption, and glucose uptake were measured simultaneously in both legs using [15O]H2O, [15O]O2, [18F]fluoro-deoxy-glucose, and positron emission tomography.Results: The obese subjects exhibited resistance to insulin stimulation of glucose uptake in resting muscle, regardless of whether glucose uptake was expressed per kilogram of femoral muscle mass (p = 0.001) or per the total mass of quadriceps femoris muscle. At similar workloads, oxygen consumption, blood flow, and glucose uptake were lower in the obese than the nonobese subjects when expressed per kilogram of muscle, but similar when expressed per quadriceps femoris muscle mass.Discussion: We conclude that obesity is characterized by insulin resistance of glucose uptake in resting skeletal muscle regardless of how glucose uptake is expressed. When compared with nonobese individuals at similar absolute workloads and under identical hyperinsulinemic conditions, the ability of exercise to increase muscle oxygen uptake, blood flow, and glucose uptake per muscle mass is blunted in obese insulin-resistant subjects. However, these defects are compensated for by an increase in muscle mass.Keywords: insulin resistance, imaging, oxygen, isometric force, positron emission tomographyObesity 01/2003; 11(2):257-265. · 4.28 Impact Factor -
Article: Plasma asymmetric dimethylarginine and hyperemic myocardial blood flow in young subjects with borderline hypertension or familial hypercholesterolemia.
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ABSTRACT: The goal of this study was to examine the relationship between plasma asymmetric dimethylarginine (ADMA) level and hyperemic myocardial blood flow (MBF) in subjects with borderline hypertension (BHT) and familial hypercholesterolemia (FH). Asymmetric dimethylarginine is an endogenous competitive inhibitor of nitric oxide synthase that may modulate vascular function. We measured plasma ADMA levels and myocardial flow in 77 young men (mean age 35 +/- 5 years), including 47 healthy controls, 16 men with BHT, and 14 men with FH. Basal and dipyridamole-induced myocardial flow was measured using positron emission tomography. Plasma ADMA levels were measured using high-pressure liquid chromatography. Asymmetric dimethylarginine levels were significantly elevated in the BHT group compared with controls (0.59 +/- 0.13 micromol/l vs. 0.43 +/- 0.12 micromol/l, p < 0.001), and they had significantly lower dipyridamole flow (2.85 +/- 1.20 ml/min/g vs. 3.69 +/- 1.68 ml/min/g, p < 0.05). In a multivariate regression model adjusted for the study group, dipyridamole flow was inversely associated with ADMA (p < 0.05), age (p < 0.05), and apolipoprotein B concentration (p < 0.05). We conclude that plasma ADMA concentration is related to dipyridamole-induced vasodilatory function in young men, independently of blood pressure elevation and hypercholesterolemia. Subjects with BHT have significantly increased plasma ADMA levels, which may partly explain the impaired hyperemic MBF in this condition.Journal of the American College of Cardiology 10/2002; 40(7):1241-7. · 14.16 Impact Factor -
Article: Obesity affects myocardial vasoreactivity and coronary flow response to insulin.
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ABSTRACT: Obesity is associated with increased risk for cardiovascular diseases and peripheral endothelial dysfunction. We examined whether myocardial vasoreactivity and coronary-flow response to insulin stimulation are altered in obesity. Myocardial blood flow was quantitated in 10 obese men (body mass index, 33.6 +/- 1.9 kg/m(2)) and 10 healthy matched non-obese men (body mass index, 24.2 +/- 1.9 kg/m(2)), using positron emission tomography and oxygen-15-labeled water. The measurements were performed basally and during adenosine infusion (140 microg/kg per minute), with or without simultaneous physiological (1 mU/kg per minute) and supraphysiological (5 mU/kg per minute) hyperinsulinemia. Basal myocardial blood flow was not significantly different between obese and non-obese subjects. Adenosine-stimulated flow was blunted in obese (3.2 +/- 0.6 mL/g per minute) when compared with non-obese subjects (4.0 +/- 1.1 mL/g per minute, p < 0.05). Simultaneous physiological hyperinsulinemia increased adenosine-stimulated myocardial flow significantly in both groups (to 4.03 +/- 1.24 and 4.85 +/- 1.04 mL/g per minute in obese and non-obese men, respectively; p < 0.05 vs. adenosine). Supraphysiological hyperinsulinemia further enhanced the adenosine-stimulated flow in non-obese subjects (to 5.56 +/- 0.98 mL/g per minute; p < 0.05) but not in obese subjects. Young obese, healthy men have reduced myocardial vasoreactivity, which may represent an early precursor of future coronary artery disease. Additionally, insulin-induced enhancement of myocardial blood flow is blunted in obesity. Thus, endothelial dysfunction seems to also characterize myocardial vasculature of obese subjects.Obesity research 07/2002; 10(7):617-24. · 4.95 Impact Factor -
Article: Myocardial perfusion and perfusion reserve in endurance-trained men.
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ABSTRACT: This study was undertaken to determine whether endurance training is associated with changes in myocardial perfusion in humans. Myocardial perfusion was measured in eleven trained and nine sedentary men at rest and during adenosine-stimulated hyperemia using positron emission tomography (PET). Left ventricular (LV) dimensions and mass were measured using echocardiography. Myocardial work per gram of tissue was calculated as (cardiac output. mean arterial blood pressure)/LV mass. LV mass was significantly higher and myocardial work per gram of tissue lower in the trained than in the untrained subjects. Basal (0.78 +/- 0.10 and 0.76 +/- 0.15 mL. min-1. g-1, P = NS) and adenosine-stimulated perfusion (3.46 +/- 0.91 and 3.14 +/- 0.70 mL. min-1. g-1, P = NS) were similar between trained and untrained men, respectively. Consequently, myocardial perfusion reserve was similar in both groups (4.4 +/- 1.2 and 4.1 +/- 0.7, P = NS). In addition, coronary resistance at baseline (115 +/- 17 vs 119 +/- 22, mm Hg. mL. min-1. g-1, P = NS) and during adenosine infusion (28 +/- 8 vs 30 +/- 8, mm Hg. mL. min-1. g-1, P = NS) were similar in both groups. Resting myocardial work correlated with resting myocardial perfusion in both groups, but the relationship between perfusion and work was different between the groups so that perfusion for a given myocardial work was significantly higher in trained subjects (0.56 +/- 0.04 and 0.34 +/- 0.05 mL. (mm Hg. L)-1, P < 0.001). These findings suggest that endurance trained subjects do not have different resting or adenosine-stimulated myocardial perfusion. However, the relationship between myocardial perfusion and work appears altered in the athletes.Medicine & Science in Sports & Exercise 06/2002; 34(6):948-53. · 4.43 Impact Factor -
Article: Dose-dependent vasodilating effects of insulin on adenosine-stimulated myocardial blood flow.
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ABSTRACT: In the peripheral vasculature, insulin induces time- and dose-dependent vasodilation. We have recently demonstrated that insulin potentiates adenosine-stimulated myocardial blood flow. However, it is unknown whether insulin's effects on the coronary vasculature are dose dependent. In this study, we quantitated myocardial blood flow and adenosine-stimulated coronary flow (140 microg.kg(-1).min(-1) for 5 min) in 10 healthy men (age, 32 +/- 6 years; BMI, 24.1 +/- 1.8 kg/m(2)) using positron emission tomography and (15)O-labeled water. Hyperemic myocardial blood flow was measured in the basal state, during euglycemic physiological hyperinsulinemia (serum insulin approximately 65 mU/l) and during supraphysiological hyperinsulinemia (serum insulin approximately 460 mU/l). Basal myocardial blood flow was 0.84 +/- 0.17 ml.g(-1).min(-1). Physiological hyperinsulinemia increased the adenosine-stimulated flow by 20% (from 3.92 +/- 1.17 to 4.72 +/- 0.96 ml.g(- 1).min(-1); P < 0.05). Supraphysiological hyperinsulinemia further enhanced the adenosine-stimulated flow by 19% (to 5.61 +/- 1.03 ml.g(-1).min(-1); P < 0.05). These effects were not explained by changes in systemic hemodynamics, since coronary resistance decreased during each insulin infusion (P < 0.05). In addition, hyperemic myocardial blood flow responses during insulin stimulation were positively correlated with whole-body glucose uptake. The results demonstrate that insulin is able to enhance hyperemic myocardial blood flow in a dose-dependent manner in healthy subjects. These effects might contribute to the known beneficial dose-dependent effects of insulin on myocardial ischemia.Diabetes 05/2002; 51(4):1125-30. · 8.29 Impact Factor -
Article: Early impairment of coronary flow reserve is not associated with Chlamydia pneumoniae antibodies.
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ABSTRACT: Chlamydia pneumoniae infection has been associated with atherosclerosis by sero-epidemiological, histopathological and interventional studies, and animal experiments. We hypothesized that if chlamydial infection is causative of atherosclerosis, the occurrence of antibodies against C. pneumoniae should be associated with coronary vasomotor dysfunction - an early sign of atherosclerosis. To study the association between C. pneumoniae infection and coronary vasomotor function in young men without signs of ischemic heart disease. Serum IgG and IgA antibody concentrations against C. pneumoniae were determined in 125 clinically healthy subjects undergoing positron emission tomography (PET) studies. Myocardial blood flow was measured at rest and during pharmacologically induced hyperemia using [15O]H2O Coronary flow reserve was calculated as the ratio of hyperemic blood flow to resting blood flow. No association was found between serum C. pneumoniae antibody concentrations and myocardial blood flow parameters. In contrast, more conventional risk factors for coronary artery disease, such as total cholesterol and apolipoprotein B, were inversely associated with hyperemic flow and flow reserve. We found no association between C. pneumoniae antibodies and coronary vasomotor function in subjects without ischemic heart disease. Thus, these results do not support the role of C. pneumoniae infection as an early phase risk factor for coronary artery disease.Annals of Medicine 02/2002; 34(4):284-90. · 3.52 Impact Factor -
Article: Blunted coronary vasoreactivity to insulin is an early alteration in hypertension.
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ABSTRACT: Insulin resistance in the heart is not localized to the myocardium, but may also occur in blood vessels. We studied the effects of insulin on coronary vasodilation in hypertension. Coronary vascular resistance was quantitated in 11 nonsmoking men with untreated mild essential hypertension and 9 healthy normotensive men using positron emission tomography and (15)O-labeled water. The measurements were performed at baseline and during adenosine infusion (140 microg x kg(-1) x min(-1)) with or without simultaneous euglycemic physiological (serum insulin approximately 70 mU/l) and supraphysiological (serum insulin approximately 460 mU/l) hyperinsulinemia. Coronary resistance was significantly higher in hypertensive than normotensive subjects at baseline and during adenosine infusion. Physiological hyperinsulinemia decreased hyperemic coronary resistance significantly in both groups. Supraphysiological hyperinsulinemia further decreased the hyperemic coronary resistance in normotensive but not in hypertensive subjects, leading to higher hyperemic coronary resistance in hypertensive than normotensive subjects (27.2 +/- 8.7 vs. 19.2 +/- 4.9 mm Hg x min x g x ml(-1), p < 0.05). However, insulin-stimulated whole body glucose uptake values were similar between the groups during both insulin infusions. In conclusion, insulin-induced coronary vasodilation is blunted in young subjects with mild essential hypertension who are otherwise healthy. Coronary vascular resistance to insulin occurs although no change in peripheral glucose uptake can be detected. While we do not know whether the same results can be extrapolated to female or older subjects, these results indicate a novel defect in the regulation of coronary arteries in the early phase of hypertension.Journal of Vascular Research 40(1):58-67. · 2.65 Impact Factor -
Article: Increased coronary vascular resistance cannot be reduced by inhibiting sympathetic overactivity in hypertension.
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ABSTRACT: The aim of this study was to test whether increased coronary vascular resistance in hypertensive subjects can be reduced by centrally inhibiting sympathetic overactivity with dexamethasone. Coronary vascular resistance was quantitated in 11 men with untreated mild essential hypertension (RR 149 +/- 13/98 +/- 10 mm Hg) and 23 healthy, normotensive, otherwise matched men using positron emission tomography and [(15)O]H(2)O. The measurements were performed at baseline and during adenosine stimulation. Each subject was studied twice, with and without previous dexamethasone treatment for two days (0.5 mg x 4 per day). Before dexamethasone treatment, cardiac index and plasma norepinephrine concentration (1.9 +/- 0.6 vs. 1.3 +/- 0.5 nmol/l, p < 0.01) were significantly higher in hypertensive than in normotensive subjects. Additionally, both baseline and hyperemic coronary vascular resistances were higher in hypertensive than normotensive subjects (147 +/- 31 vs. 113 +/- 24 and 36 +/- 9 vs. 25 +/- 10 mm Hg.min.g.ml(-1); p < 0.05). Dexamethasone treatment significantly decreased plasma norepinephrine concentrations in hypertensive subjects, leading to comparable plasma norepinephrine concentrations in hypertensive and normotensive subjects (1.4 +/- 0.5 vs. 1.2 +/- 0.4 nmol/l; NS). However, coronary vascular resistances remained increased in hypertensive subjects. In conclusion, hypertensive subjects are characterized by sympathetic overactivity, which can be normalized by dexamethasone. However, coronary vascular resistances remained increased in hypertensive subjects after dexamethasone treatment, suggesting that other mechanisms than sympathetic overactivity-induced vasoconstriction explain the increased coronary vascular resistance in hypertension.Journal of Vascular Research 39(5):456-62. · 2.65 Impact Factor
Top co-authors
Top Journals
Institutions
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2002–2011
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University of Turku
- Turku PET Centre
Turku, Western Finland, Finland -
Turku centre for biotechnology, finland
Turku, Western Finland, Finland
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2005
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Turku University Hospital
- Turku PET Centre
Turku, Western Finland, Finland
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2003
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University of Helsinki
Helsinki, Province of Southern Finland, Finland
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