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Clinical Hemorheology and Microcirculation 44 (2010) 287–296
DOI 10.3233/CH-2010-1278
IOS Press
287
No apparent correlation between Behc¸et’s
disease and oxidative stress disturbance
Hayrettin Saglama,∗, Eser Kayab, Mustafa Cemekc, Yüksel C¸ic¸ekd,
Mustafa Kulaceand Semsettin Karacaf
aDepartment of Cardiology, Acıbadem Hospital, Kayseri, Turkey
bDepartment of Nuclear Medicine, Acıbadem Hospital, Kayseri, Turkey
cDepartment of Chemistry, Faculty of Science and Arts, Kocatepe University, Afyonkarahisar, Turkey
dDepartment of Cardiology, OSM Middle East Hospital, S¸anlıurfa, Turkey
eDepartment of Dermatology, Faculty of Medicine, Namık Kemal University, Tekirda˘g, Turkey
fDepartment of Dermatology, Faculty of Medicine, Kocatepe University, Afyonkarahisar, Turkey
Abstract. Behc¸et’s disease (BD) is a chronic, progressive and inflammatory multisystemic disease, that significantly affects the
cardiovascular system. Oxidative stress (OS) is a disturbance in oxidant/antioxidant balance in favor of oxidants. The OS that
increases acutely and chronically due to the inflammatory process plays an important role in the pathogenesis of the cardiovascular
system effects of the disease by causing endothelial dysfunction in vascular structures. The aim of our study was to investigate
the relationship between OS and myocardial perfusion, which is based on microvascular dysfunction, in BD.
Material and method: Twenty-seven patients with BD (16 M, 11 F, mean age: 38.7 ±9.4 years) and 22 healthy volunteers (12 M,
10 F, mean age: 35.8±6.5 years) participated in our study. Technetium-99m methoxyisobutylisonitrile single photon emission
computed tomography (Tc-99m MIBI SPECT) stress-rest test was performed with two-day protocol. Myocardial perfusion
scores (summed stress score, summed rest score, summed difference score, fix defect score) and perfusion defect prevalence
(stress, rest, ischemic and fixed) were determined as the percentage of left ventricle. Coronary angiography was performed in
patients with abnormal myocardial perfusion scintigraphy. For OS analysis, the blood samples were taken immediately before
the first imaging procedure and were studied for malondialdehyde, glutathione, nitrite, nitrate, vitamin C, retinol, and carotene.
Results: In the BD group, a total of 9 patients had abnormal findings in their stress and rest electrocardiography. Perfusion
defect in myocardial perfusion scintigraphy was observed in 14 patients (51.8%). Twelve patients accepted coronary angiography,
and their results were normal. In the comparison of myocardial perfusion scores, perfusion defect prevalence and OS parameters,
there was a significant difference between the BD and control groups. In the BD group, no correlation was observed between
myocardial perfusion scores, perfusion defect prevalence and OS parameters.
Conclusion: Defects in myocardial perfusion and increase in OS were observed in BD; however, there was no correlation
between the two findings in the inactive period. In other words, the prevalence and intensity of myocardial perfusion defects can
vary at different OS levels.
Keywords: Behc¸et’s disease, myocardial perfusion scintigraphy, oxidative stress
1. Introduction
Behc¸et’s disease (BD) is a chronic, progressive and multisystemic inflammatory disorder of unknown
origin, characterized by various clinical symptoms [12, 25]. It generally involves ocular, articular, genital,
vascular, and gastrointestinal structures and the central nervous system [40]. The cardiovascular system
is involved in BD in 60% of cases, and the mortality rate is 20% [10, 17, 23]. Myocarditis, endocarditis,
∗Corresponding author: Hayrettin Saglam, M.D., Acıbadem Hospital, Kayseri, Turkey. Tel.: +90 352 207 3977; Fax: +90 352
207 43 43; E-mail: drsaglam69@yahoo.com.
1386-0291/10/$27.50 © 2010 – IOS Press and the authors. All rights reserved
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288 H. Saglam et al. / No apparent correlation between Beh ¸cet’s disease and oxidative stress disturbance
pericarditis, coronary arteritis, thrombus, atrial fibrillation, valvular dysfunction, aortic stenosis, aortic
aneurysm, left ventricular aneurysm, dilated cardiomyopathy, silent myocardial ischemia (SMI), acute
myocardial infarct, and sudden cardiac death are defined in Cardio-Behc¸ et [7, 14, 39].
Oxidative stress (OS) is the impairment in the oxidative/antioxidative balance in favor of antioxidants
[6, 35]. Acute and chronic OS is a serious factor for vascular endothelial dysfunction, and it plays an
important role in the pathogenesis of various vascular diseases [24]. The inflammatory process in BD
increases OS and is implicated in the pathogenesis of the disease [6].
In this study, we aimed to investigate the relationship between OS and myocardial perfusion, based on
microvascular dysfunction, in BD.
2. Material and method
Twenty-seven patients with BD (16 M, 11 F; mean age: 38.7 ±9.4 years, range: 19–66 years) and 22
healthy volunteers as a control group (12 M, 10 F; mean age: 35.8 ±6.5 years, range: 20–54 years) were
included in our study. Patients with any risk factor for coronary artery disease (diabetes mellitus, hyper-
tension, smoking, hyperglycemia, or family history) were excluded. Myocardial perfusion scintigraphy
(MPS) study was performed when the disease was inactive. The study was approved by the Medical
Ethics Committee of Afyon Kocatepe University School of Medicine. All participants were informed
about the study, and their written informed consent was obtained.
3. Exercise stress testing
Patients performed symptom-limited treadmill exercise adhering to the Bruce protocol with standard
clinical end points. Heart rate and blood pressure were measured every 3 minutes (min), and electro-
cardiography (ECG) was monitored continuously. Technetium-99m methoxyisobutylisonitrile single
photon emission computed tomography (Tc-99m MIBI SPECT) (CARDIOSPECT, Medi-Radiopharma,
Budapest, Hungary) was injected at peak exercise and exercise was terminated 1 min later.
4. SPECT acquisition and reconstruction
The stress and rest studies were performed in a two-day protocol. The stress SPECT acquisition was
performed 30–60 min following intravenous injection of 25 mCi Tc-99m MIBI. The rest SPECT study
was performed on a separate day within 1 week from the stress study 45–60 min after intravenous injection
of 25 mCi Tc-99m MIBI. All images were acquired using a Philips single-head gamma camera (Philips
Medical Systems Gamma Diagnost, Holland) equipped with a low-energy general-purpose collimator.
Each data set was acquired over a 180◦semicircular arc extending from the right anterior oblique to left
posterior oblique position. Sixty-four projections were obtained and SPECT was performed on the image
at stress and rest by 30 s/projection. A 20% symmetric energy window centered on the 140 keV peak
was used. All images were stored in a 64 ×64 ×16 matrix with a 1.5 zoom. Filtered back-projection was
performed using a Butterworth filter with a cutoff frequency of 0.35 cycles/pixel and order 5.0. Azimuthal
definition (from the apex to base or anterior to posterior) was obtained from the mid-transverse and sagittal
slices for reconstruction of the short-axis, horizontal long-axis, and vertical long-axis slices. Attenuation
correction (coefficient 0.12 cm−1) was used.
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H. Saglam et al. / No apparent correlation between Beh ¸cet’s disease and oxidative stress disturbance 289
5. Data analysis
For visual analysis, stress and rest images were displayed on short-axis, horizontal long-axis and
vertical long-axis views. Myocardial perfusion was scored using a 17-segment model [4]. The severity of
the hypoperfusion was evaluated on a five-point grading scale (0, normal perfusion; 1, mild hypoperfusion;
2, moderate hypoperfusion; 3, severe hypoperfusion; and 4, absence of photon activity). In this model,
the left anterior descending coronary artery distribution territory comprised seven segments, and the right
coronary and left circumflex arteries were each assigned five segments. Adjusted per segment scores were
calculated for all major coronary artery territories by dividing the sum of scores of the individual segments
corresponding to a vascular territory by the number of segments in the same territory. A summed stress
score (SSS) and a summed rest score (SRS) were calculated by adding all 17 individual segment scores.
A summed difference score (SDS), a measure of stress-induced myocardial ischemia, was also calculated
by subtracting the SRS from the SSS. Fix defect score (FDS) was calculated if the same perfusion defect
score with the same segment at both stress and rest images was determined. MPS was classified as
normal (SSS: <4), mildly abnormal (SSS: 4–8), moderately abnormal (SSS: 9–13) or severely abnormal
(SSS: >13).
Defect extent was stated as a percentage of the left ventricle (%LV). For each image, defect extent was
also determined by dividing the number of abnormal segments by the total number of segments, and then
multiplying this ratio by 100 [22].
6. Blood samples
For OS analysis, 8-hour (h) fasting blood samples were taken immediately before the imaging proce-
dure on the day the first imaging was performed. Malondialdehyde (MDA), glutathione (GSH), nitrite,
nitrate, ascorbic acid (vitamin C), retinol (vitamin A) and carotene (provitamin A) were analyzed
biochemically.
6.1. Chemicals and biochemical analysis
Glutathione, thiobarbituric acid, phosphate buffer, butylated hydroxytoluene, trichloroacetic acid,
EDTA, DTNB [5,5-dithiobis-(2-nitrobenzoic acid)], disodium hydrogen phosphate, phenylenediamine,
sodium azide, 2,4-dinitrophenylhydrazine, ethanol, hexane, sodium nitrite, sodium nitrate, sulfanil-
amide, N-(1-naphthyl) ethylenediamine dihydrochloride and vanadium (III) chloride were purchased
from Sigma. All other chemicals and reagents used in this study were analytical grade.
Fasting blood samples were drawn into heparin-free tubes during routine blood sampling for biochem-
ical analyses. After immediate centrifugation (1000gfor 10 min at +4◦C), the serum was stored in a
polystyrene plastic tube at –70◦C until the time of analysis. Whole blood was collected into heparinized
tubes and whole blood MDA and GSH levels were studied on the same day of admission.
6.2. MDA assay
Whole blood MDA levels (as an important indicator of lipid peroxidation) were measured accord-
ing to a method of Jain et al. [13]. The principle of the method was based on the spectrophotometric
measurement of the color that occurred during the reaction of thiobarbituric acid with MDA. Concentra-
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290 H. Saglam et al. / No apparent correlation between Beh ¸cet’s disease and oxidative stress disturbance
tion of thiobarbituric acid reactive substances (TBARS) was calculated by the absorbance coefficient of
malondialdehyde–thiobarbituric acid complex and expressed in nmol/ml [13].
6.3. Nitrate and nitrite analysis
The concentrations of nitric oxide (nitrate and nitrite) were detected by the methods of Miranda et al.
[27]. Nitrite and nitrate calibration standards were prepared by diluting sodium nitrite and sodium
nitrate in pure water. After loading the plate with samples (100l), addition of vanadium (III) chlo-
ride (100 l) to each well was rapidly followed by addition of the Griess reagents, sulfanilamide (50 l)
and N-(1-naphthyl) ethylenediamine dihydrochloride (50 l). The Griess solutions may also be premixed
immediately prior to application to the plate. Nitrite mixed with Griess reagents forms a chromophore
from the diazotization of sulfanilamide by acidic nitrite followed by coupling with bicyclic amines, such
as N-1-(naphthyl) ethylenediamine. Blank sample values were obtained by substituting diluting medium
for Griess reagent. Nitrite was measured in a similar manner except that samples and nitrite standards
were only exposed to Griess reagents. The absorbance at 540 nm was read to assess the total level of
nitrite and nitrate in all samples [27].
6.4. GSH assay
Estimation of reduced glutathione was measured using the spectrophotometric method of Beutler et al.
[2]. After lysing whole blood and removal of precipitate, disodium hydrogen phosphate and DTNB
solution were added and the color formed was read at 412 nm. The results were expressed in mg/dl [2].
6.5. Ascorbic acid, retinol and β-carotene analysis
Serum vitamin C (ascorbic acid) level was determined after derivatization with 2,4-
dinitrophenylhydrazine [29]. The levels of -carotene at 425nm and vitamin A (retinol) at 325 nm were
detected after the reaction of serum : ethanol : hexane at the ratio of 1:1:3,respectively [37].
7. Coronary angiography
Coronary angiography (CAG) was recommended to patients with abnormal MPS. CAG was performed
by Judkin’s technique. Stenoses of coronary vessels were coded according to the American Heart Associa-
tion criteria [27]. Angiographic demonstration of stenosis of ≥50% of any one of the epicardial coronary
arteries was considered severe. A luminal coronary stenosis of 50%–75% was considered moderate,
whereas a luminal coronary stenosis >75% was considered severe.
8. Statistical analysis
All results were expressed as mean ±standard deviation for all subjects. Independent samples ttest,
Mann–Whitney U, paired samples ttest, McNemar test, one-way ANOVA, Chi-square test, and Pearson’s
correlation analysis were used in statistical analysis. A Pvalue less than 0.05 was considered to be
statistically significant.
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H. Saglam et al. / No apparent correlation between Beh ¸cet’s disease and oxidative stress disturbance 291
Table 1
The clinical and cardiologic findings in patient and control groups
Clinical findings BD group (n= 27) Control group (n= 22) Pvalue
Age (Years) 38.7 ±9.4 35.8 ±6.5 0.756
Sex (Male/Female) 16/11 12/10 0.740
Blood pressure (mm/Hg)
Systole 108.0 ±11.5 115.8 ±14.9 0.067
Diastole 72.8 ±10.7 77.9 ±9.8 0.115
Heart rate (beats per minute) 75.1 ±5.6 72.6 ±5.2 0.136
Abnormal rest ECG, n(%) 6 (22.2%) 0 (0%) –
Pathologic Q wave 4 (14.8%) 0 (0%) –
Negative T wave 1 (3.7%) 0 (0%) –
ST depression 1 (3.7%) 0 (0%) –
Exercise ECG change
ST depression (>0.5 mm) 4 (14.8%) 1 (4.5%) 0.704
ST elevation 2 (7.4%) 0 (0%) –
9. Results
The clinical and cardiologic findings in the patient and control groups are shown in Table 1. In the BD
group, there were abnormal findings in the stress and rest ECG of 9 patients. Perfusion defect in MPS
was found in 14 patients (51.9%). In the stress study in the BD group, SSS was found as normal in 13
patients (48.1%). Twelve patients accepted the CAG procedure and all the results were normal. In the
comparison of myocardial perfusion scores, perfusion defect prevalence and OS parameters, there was
a significant difference between BD and control groups (Table 2). In the comparison of clinical features
Table 2
The comparison of myocardial perfusion scores, perfusion defect prevalence and OS parameters in BD and control groups
SPECT findings BD group (n= 27) Control group (n= 22) Pvalue
SSS 8.7 ±6.8 2.4 ±1.2 <0.001
SRS 4.3 ±3.4 0.6 ±1.0 0.001
SDS 4.7 ±3.6 1.5 ±1.1 0.002
Stress defect (%LV) 29.2 ±13.2 11.4 ±8.7 0.004
Rest defect (%LV) 15.5 ±14.6 4.6 ±3.5 0.003
˙
Ischemic defect (%LV) 14.2 ±8.6 6.9 ±7.1 0.189
Oxidative stress parameters
Malondialdehyde 4.69 ±0.53 1.43 ±0.58 0.001
Glutathione 30.33 ±4.65 36.48 ±5.13 0.001
Nitrite 1.89 ±0.87 0.98 ±0.43 0.001
Nitrate 7.89 ±1.56 6.86 ±1.54 0.021
Vitamin C 0.31 ±0.74 1.61 ±0.86 <0.001
Retinol 51.17 ±5.85 57.69 ±6.71 0.002
Carotene 19.87 ±4.46 24.72 ±3.34 0.001
SSS: summed stress score; SRS: summed rest score; SDS: summed difference score.
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Table 3
The clinical features of BD patients with and without normal/abnormal MPS
Clinical feature BD group SSS≥4
(abnormal MPS)
n=14
BD group SSS < 4
(normal MPS)
n=13
Pvalue
Age (Years) 39.5 ±11.6 36.8 ±5.4 0.876
Sex (Male/Female) 11/6 5/5
Disease duration (Years) 8.9. ±6.4 5.9 ±4.3 0.011
Symptoms
Oral ulcer 13/14 9/13 0.612
Eye lesion 3/14 3/13 0.642
Genital ulcer 13/14 9/13 0.612
Skin lesion 6/14 7/13 0.736
Arthralgia 8/14 7/13 0.927
Gastrointestinal involvement 2/14 1/13 1.000
Deep vein thrombosis 0/14 0/13 –
Positive pathergy test 10/14 2/13 0.083
Neurological finding 3/14 1/13 0.607
Treatment
Cholchicine 14/14 5/13 0.186
Cyclosporine 1/14 0/13 –
Cytotoxic agent 2/14 0/13 –
of the patients with and without perfusion defect, differences were significant in terms of the duration
of the disease (P= 0.010) (Table 3). However, there was no difference among the BD patients with and
without perfusion defect in terms of OS parameters (Table 4). In the BD group, no correlation was found
between myocardial perfusion scores, perfusion defect prevalence and OS parameters.
10. Discussion
Histopathological studies in BD, an inflammatory, progressive disease, have shown that the dominant
lesion is vasculitis, and vascular wall and perivascular tissues are involved throughout [5, 14, 31].
Reactive oxygen species (ROS) are the products that include molecular oxygen and appear due to
normal aerobic metabolism. (ROS: oxygen-derived free radicals: superoxide anion, hydroxyl radical,
nitric oxide, lipid radical. Non-free radicals: hydrogen peroxide, peroxynitrite, hypochloric acid) [3, 18].
ROS increase dramatically with the effect of activated neutrophils in inflammation. Cells and tissues resist
the potential damaging effect of ROS by developing a defense with antioxidant vitamins and enzymes. OS
is defined as the increase in ROS due to insufficient antioxidant defense during the inflammation [18]. The
molecular and cellular mediators of the inflammation and increased ROS impair the oxidant/antioxidant
balance [6] and cause cell/tissue damage by forming the destructive reaction [1, 6, 38].
The researchers who have pointed out that the mechanism underlying vasculitis in BD results from
autoimmunity [38] showed that the increase in ROS, phagocytosis and chemotaxis occurs depending on
abnormal neutrophil function [6]. Furthermore, cytokines and chemokines increase in the inflammation
site [24].
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H. Saglam et al. / No apparent correlation between Beh ¸cet’s disease and oxidative stress disturbance 293
Table 4
The OS parameters and SPECT findings of the patients with and without abnormal/normal MPS
findings in the BD group
SPECT findings BD group SSS≥4
(abnormal MPS)
n=14
BD group SSS < 4
(normal MPS)
n=13
Pvalue
SSS 13.4 ±6.8 2.2 ±0.54 <0.001
SRS 6.9 ±2.6 0.9 ±0.5 <0.001
SDS 6.8 ±1.9 1.6 ±0.7 <0.001
Stress (%LV) 41.8 ±7.3 12.7 ±6.9 0.001
Rest (%LV) 26.5 ±9.3 5.1 ±4.6 <0.001
˙
Ischemic (%LV) 15.8 ±4.7 7.4 ±8.3 0.097
Oxidative stress parameters
Malondialdehyde 4.54 ±0.57 3.65 ±0.87 0.346
Glutathione 31.12 ±3.89 31.98 ±2.75 0.693
Nitrite 1.35 ±0.62 1.17 ±0.28 0.768
Nitrate 7.76 ±1.42 7.32 ±0.68 0.653
Vitamin C 0.33 ±0.22 0.34 ±0.17 0.865
Retinol 50.46 ±5.54 51.34 ±6.41 0.686
Carotene 20.17 ±3.26 20.54 ±2.34 0.264
SSS: summed stress score; SRS: summed rest score; SDS: summed difference score.
In BD, the products of lipid peroxidation and pro-oxidants are also increased [5]. In the study by Taysi
et al. [38] evaluating the oxidant/antioxidant situation in BD, the presence of increased OS was shown
by lipid peroxidation impairment and decline in erythrocyte antioxidant defense system.
In an inflammatory situation, ROS increasing with the effect of active neutrophils causes lipid peroxi-
dation on the cell membrane, and increases the level of MDA, which is accepted as a lipid peroxidation
index. In the study of BD carried out by Köse et al. [21], the increase in the level of MDA was similar to
that of our study. ROS inactivates the function of glutathione peroxidase under OS conditions [20]. Thus,
the level of GSH, which acts as a cofactor for glutathione peroxidase, also decreases. GSH, vitamin C,
retinol, and carotene (defense against oxide molecules) levels in plasma and erythrocyte levels were
shown as decreased in other studies [18, 28].
In the active period of BD, inflammatory cytokines stimulate nitric oxide (NO) synthesis. Hence, nitrite
and nitrate which are the unstabilized molecules of NO, increase [32]. However, this was not the case in
studies of Chamber et al. [5] and Orem et al. [30], because they observed a decrease in the plasma levels
of nitrite and nitrate in the active period of the disease. In our study, we observed an increase in the levels
of nitrite and nitrate.
Endothelial dysfunction plays an important role in the pathophysiology of vascular disorders. The
barrier function of vascular endothelium is of the utmost importance in cardiovascular hemostasis. This
function is provided by the balance between cytokines, inflammatory mediators or oxidants [26]. The
increased ROS products in inflammation cause damage to the endothelial tissue [5, 38]. The release of
mediators that have a powerful vasodilator effect and are synthesized from the endothelium, such as
prostacyclin and NO, is impaired [18]. Furthermore, ROS strongly inactivates NO that is released from
the endothelium [3]. Due to the decreased NO activity, vasoconstriction, thrombocyte aggregation, and
endothelial monocyte adhesion develop in the acute and chronic phase [24]. Hence, the vascular severity of
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294 H. Saglam et al. / No apparent correlation between Beh ¸cet’s disease and oxidative stress disturbance
the disease increases [5, 9]. In OS, microvascular thrombus leads to cellular ischemia in the endothelium
due to the involvement of intramyocardial and small coronary arteries [34]. This causes impairment
in the microcirculation and myocardial ischemia/infarct develops [10, 11]. In BD, ischemia/infarct can
occur asymptomatically – even without angina or similar symptoms – due to the neuronal damage in the
myocardial sensory neurons (autonomic nervous system dysfunction) [7, 15, 39].
Myocardial perfusion scintigraphy is a non-invasive and technically simple method providing impor-
tant contributions to prognosis, risk assessment and treatment monitoring as well as in determining the
presence, severity, and prevalence of infarct and/or ischemia [8, 33]. To our knowledge, there are only
a few studies in the literature evaluating myocardial perfusion in BD using scintigraphy [9, 16, 39]. On
the other hand, since there has been no no previous study indicating the relationship between myocardial
perfusion and OS, we were unable to compare our findings to those of other similar studies.
In the comparison of perfusion scores and OS parameters of the patient and control groups, there was
a meaningful difference. When we compare the patient group itself, based on MPS findings, differences
were significant between the groups with or without abnormal MPS in terms of perfusion scores. However,
there was no difference in terms of OS parameters in the same group. On the other hand, we speculate that
meaningful differences could be found based on results established in the active period of the disease and
in the studies that included more patients. According to our findings, there was no correlation between
perfusion scores and OS parameters in BD. We believe that the findings could be quite different in a
larger number of patients and if conducted during the active period of the illness.
There are a number of markers indicating OS (oxidants, antioxidants, enzymatic, non-enzymatic, trace
elements) [20, 38]. Plasma and erythrocyte MDA level, oxidation protein products and measurements of
protein carbonyls are also used as OS indexes in BD [6]. Further studies are needed in order to determine
the ideal parameters that indicate OS and are related to myocardial perfusion in BD.
The severe inflammation in BD leads to OS, and microcirculation is impaired due to the development
of endothelial dysfunction in endomyocardial vascular structures [5, 38]. We think that myocardial per-
fusion in Cardio-Behc¸et should be preferentially evaluated with MPS due to the facts that 1, CAG is
an invasive procedure and frequently produces normal results; 2, OS markers do not show a correla-
tion with myocardial perfusion impairment according to our findings; and 3, invasive procedures is not
recommended due to the increased tissue fragility [19, 36].
11. Conclusion
Defects in myocardial perfusion and increase in OS were observed in BD; however, there was no
correlation between the two findings in the inactive period. In other words, the prevalence and intensity
of myocardial perfusion defects can vary according to different OS levels.
References
[1] S.Y. Akaydin, A. Sepici, Y. Ozkan, B. Simsek and V. Sepici, Evaluation of allantoin levels as a new marker of oxidative
stress in Behcet’s disease, Scand J Rheumatol 35 (2006), 61–64.
[2] E. Beutler, O. Duron and B.M. Kelly, Improved method for the determination of blood glutathione, J Lab Clin Med 61
(1963), 882–888.
[3] H. Cai and D.G. Harrison, Endothelial dysfunction in cardiovascular diseases, The role of oxidant stress, Circ Res 87
(2000), 840–844.
AUTHOR COPY
H. Saglam et al. / No apparent correlation between Beh ¸cet’s disease and oxidative stress disturbance 295
[4] M.D. Cerqueira, N.J. Weissman, V. Dilsizian, et al., Standardized myocardial segmentation and nomenclature for tomo-
graphic imaging of the heart: a statement for healthcare professionals from the Cardiac Imaging Committee of the Council
on Clinical Cardiology of the American Heart Association, Circulation 105 (2002), 539–542.
[5] J.C. Chambers, D.O. Haskard and J.S. Kooner, Vascular endothelial function and oxidative stress mechanisms in patients
with Behc¸et’s syndrome, J Am Coll Cardiol 37 (2001), 517–520.
[6] A.S. Dincel, Y. Ozkan, S.Y. Akaydin, G.K. Karatas, M. Onder and B. Simsek, The association between total antioxidant
status and oxidative stress in Behc¸et’s disease, Rheumatol Int 26 (2006), 1005–1009.
[7] K. Gemici, I. Baran, S. Gullulu, A.R. Kazazoglu, J. Cordan and Z. Ozer, Evaluation of diastolic dysfunction and repolar-
ization dispersion in Behc¸et’s disease, Int J Cardiol 73 (2000), 143–148.
[8] V. Go, M.R. Bhatt and R.C. Hendel, The diagnostic and prognostic value of ECG-gated SPECT myocardial perfusion
imaging, J Nucl Med 45 (2004), 912–921.
[9] I.H. Gullu, M. Benekli, H. Muderrisoglu, et al., Silent myocardial ischemia in Behc¸et’s disease, J Rheumatol 23 (1996),
323–327.
[10] C. Gurgun, E. Ercan, C. Ceyhan, et al., Cardiovascular involvement in Behc¸et’s disease, Jpn Heart J 43 (2002), 389–398.
[11] D.L. Huong, B. Wechsler, T. Papo, et al., Endomyocardial fibrosis in Behc¸et’s disease, Ann Rheu Dis 56 (1997), 205–208.
[12] International Study Group for Behc¸et’s Disease, Criteria for diagnosis of Behc¸et’s disease, Lancet 335 (1990), 1078–1080.
[13] S.K. Jain, R. McVie, J. Duett and J.J. Herbst, Erythrocyte membrane lipid peroxidase and glycosylated hemoglobin in
diabetes, Diabetes 38 (1989), 1539–1543.
[14] D.G. James and A. Thomson, Recognition of the diverse cardiovascular manifestations in Behc¸et’s disease, Am Heart J
103 (1982), 457–458.
[15] K. Karata, M. Onder and J. Meray, Autonomic nervous system involvement in Behc¸et’s disease, Rheumatol Int 22 (2002),
155–159.
[16] E. Kaya. H. Saglam, I. Ciftci, M. Kulac, S. Karaca and M. Melek, Evaluation of myocardial perfusion and function by
gated SPECT in patients with Behc¸et’s disease, Ann Nucl Med 22 (2008), 287–295.
[17] Y. Koc¸, I. Güllü, G. Akpek, et al., Vascular involvement in Behc¸et’s disease, J Rheumatol 19 (1992), 402–410.
[18] I. Kokcam and M. Nazıroglu, Effects of vitamin E supplementation on blood antioxidants levels in patients with Behc¸et’s
disease, Clin Biochem 35 (2002), 633–639.
[19] F. Kosar, I. Sahin, H. Gullu and S. Cehreli, Acute myocardial infarction with normal coronary arteries in a young man with
the Behc¸et’s disease, Int J Cardiol 99 (2005), 355–357.
[20] K. Kose, P. Dogan, M. Ascioglu, K. Erkilic and O. Ascioglu, Oxidative plasma of stress and antioxidant defenses in patients
with Behc¸et’s disease, Tohoku J Exp Med 176 (1995), 239–248.
[21] K. Kose, C. Yazıcı, N. Cambay, O. Ascıoglu and P. Dogan, Lipid peroxidation and erythrocyte antioxidant enzymes in
patients with Behc
¸et’s disease, Tohoku J Exp Med 197 (2002), 9–16.
[22] M.G. Levine, A.W. Ahlberg, A. Mann, et al., Comparison of exercise, dipyridamole, adenosine, and dobutamine stress
with the use of Tc-99m tetrofosmin tomographic imaging, J Nucl Cardiol 6(1999), 389–396.
[23] J.T. Lie, Vascular involvement in Behc¸ et’s disease: arterial and venous and vessels of all sizes, J Rheumatol 19 (1992),
341–343.
[24] H. Lum and K.A. Roebuck, Oxidant stress and endothelial cell dysfunction, Am J Physiol Cell Physiol 280 (2001), 719–741.
[25] S.E. Marshall, Behc¸et’s disease, Best Pract Res Clin Rheumatol 18 (2004), 291–311.
[26] K.E. McQuaid and A.K. Keenan, Physiological society symposium: impaired endothelial and smooth muscle cell function
in oxidative stres, Exp Physiol 82 (1997), 369–376.
[27] K.M. Miranda, M.G. Espey and D.A. Wink, A rapid, simple spectrophotometric method for simultaneous detection of
nitrate and nitrite, Nitric Oxide 5(2001), 62–71.
[28] T. Noyan, I. Sahin, M.R. Sekero˘
glu and H. Dülger, The serum vitamin C levels in Behc¸et’s disease, Yonsei Med J 30 (2003),
771–778.
[29] S.T. Omaye, J.D. Turnbul and H.E. Savberlich, Ascorbic acid analysis. II. Determination after derivatisation with 2,2,dini-
trophenylhydrazine. Selected methods for determination of ascorbic acid in animal cells tissues and fluids, In: D.B.
McCormick and L.D. Wright, eds, Methods in Enzymology, Academic Press, New York, 1979, pp. 7–8.
[30] A. Orem, B. Vanizor, G. Cimsit, E. Kiran, O. Deger and M. Malkoc, Decreased nitric oxide production in patients with
Behcet’s disease, Dermatology 198 (1999), 33–36.
[31] T. Sakane, M. Takeno, N. Suzuki and G. Inaba, Behc¸et’s disease, N Engl J Med 341 (1999), 1284–1291.
[32] B. Sancak, M. Onder, M.O. Oztas, N. Bukan and M.A. Gurer, Nitric oxide levels in Behc¸et’s disease, JEADV 17 (2003),
7–9.
AUTHOR COPY
296 H. Saglam et al. / No apparent correlation between Beh ¸cet’s disease and oxidative stress disturbance
[33] R. Sciagra and M. Leoncini, Gated single-photon emission computed tomography, The present-day “one-stop-shop” for
cardiac imaging, Q J Nucl Med 49 (2005), 19–29.
[34] U. Shmitz-Haubner and J. Knop, Evidence for endothelial cell dysfunction in association with Behc¸et’s disease, Thromb
Res 34 (1984), 277–285.
[35] H. Sies, Oxidative stres: Oxidant and antioxidants, Exp Physiol 82 (1997), 291–295.
[36] M. Sismanoglu, S.N. Omeroglu, D. Mansuroglu, et al., Coronary artery disease and coronary artery bypass grafting in
Behc¸et’s disease, J Card Surg 20 (2005), 160–163.
[37] I. Suzuki and N. Katoh, A simple and cheap method for measuring serum vitamin A in cattle using spectrophotometer,
Jpn J Vet Sci 52 (1990), 1281–1283.
[38] S. Taysi, B. Demircan, N. Akdeniz, M. Atasoy and R.A. Sari, Oxidant/antioxidant status in men with Behc¸et’s disease,
Clin Rheumatol 26 (2007), 418–422.
[39] S. Turkolmez, N. Gokcora, M. Alkan and M.A. Gürer, Evaluation of myocardial perfusion in patients with Behc¸ et’s disease,
Ann Nucl Med 19 (2005), 201–206.
[40] H. Yazıcı, S. Yurdakul and V. Hamuryudan, Behc¸ et’s syndrome, In: J.H. Klippel and P.A Dieppe, eds, Rheumatology,
Vol. 2, Mosby, London, 26 (1998), 1–6.
