Ahmet Alver
Karadeniz Technical University
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Featured researches published by Ahmet Alver.
Archives of Oral Biology | 2008
Esra Baltacıoğlu; Ferda Alev Akalın; Ahmet Alver; Orhan Deger; Erdem Karabulut
OBJECTIVE Evidence reveals the role of reactive oxygen species (ROS) in many pathologies including periodontitis. Protein carbonylation is the most widely used biomarker for oxidative damage to proteins, and reflects cellular damage induced by ROS. In this study protein carbonyl (PC) levels in serum and gingival crevicular fluid (GCF) in patients with chronic periodontitis (CP) was evaluated. MATERIALS AND METHODS Thirty-three patients with CP and 24 healthy controls were included in the study. Following the clinical measurements and samplings, total protein levels in serum and GCF were determined by Bradford method, and serum and GCF PC levels were measured by modified Levine method. RESULTS PC levels in serum and GCF were significantly higher in the CP group compared to the control group (p<0.05). In all subjects, serum and GCF PC levels showed statistically significant positive correlations with all clinical parameters (p<0.05). CONCLUSIONS The results suggest that both systemic and local/periodontal protein carbonylation increase in CP compared to health and that elevated levels of PCs may be a sign of oxidative damage in periodontitis and correlate well with the periodontal status.
Clinica Chimica Acta | 2003
Birgül Vanizor Kural; Asım Örem; Gülseren Çimşit; Hüseyin Avni Uydu; Yunus Emre Yandı; Ahmet Alver
BACKGROUND Hyperhomocysteinemia may constitute an independent risk factor for cardiovascular disease and may promote atherothrombosis. Psoriasis is one of the diseases associated with increased atherothrombosis. The aim of the present study was to examine serum total homocysteine (tHcy) level and its relationships with atherothrombotic markers. METHODS The study group included 30 patients with psoriasis (17 females and 13 males) with a mean age of 34.2 (age range: 27-40) and 30 sex and age matched healthy volunteers (15 females and 15 males) with a mean age of 36.7 (age range: 26-48). The concentrations of lipids, lipoproteins, acute phase reactants, tHcy and atherothrombotic markers [fibronectin, soluble vascular adhesion molecules-1 (sVCAM-1), soluble intercellular adhesion molecules-1 (sICAM-1), tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1), autoantibodies against oxidized LDL (AuAb-oxLDL)] were determined. RESULTS The mean levels of serum tHcy, fibrinogen, fibronectin, sICAM, PAI-1 and AuAb-oxLDL were increased in patients whereas tPA, vitamin B(12) and folate levels were decreased significantly. Increased levels of sVCAM were not statistically significant. tHcy levels were negatively correlated with vitamin B(12) (r=-0.40, P=0.027) and positively correlated with PAI-1 and AuAb-oxLDL levels (r=0.46, P=0.011; r=0.39, P=0.035, respectively). CONCLUSIONS It was concluded that the increased homocysteine concentration and altered endothelial cell-mediated proteins associated with increased lipids and LDL oxidation may play an important role for the development of atherothrombotic complications with psoriasis.
Journal of Periodontology | 2014
Esra Baltacioglu; Pınar Yuva; Güven Aydın; Ahmet Alver; Cemil Kahraman; Erdem Karabulut; Ferda Alev Akalın
BACKGROUND In this study, levels of malondialdehyde (MDA), which is a significant product of lipid peroxidation (LPO), total oxidant status (TOS), total antioxidant capacity (TAOC), and the oxidative stress index (OSI), a novel value as a marker of periodontal disease activity, are investigated in serum and saliva from patients with chronic (CP) and generalized aggressive (GAgP) periodontitis. METHODS A total of 98 patients (33 with CP, 35 patients with GAgP, and 30 periodontally healthy controls) enrolled in the study. After clinical measurements and sample collection, the MDA level, TOS, and TAOC were measured by high-performance liquid chromatography and a novel automatic colorimetric method. The OSI was calculated as [(TOS/TAOC) × 100]. RESULTS Although the salivary MDA levels and serum and salivary TOS and OSI values were significantly higher in the periodontitis groups than in the control group (P <0.05), the serum and salivary TAOC levels were significantly lower, and no significant difference in serum MDA levels was found (P >0.05). Furthermore, oxidative stress parameters were higher in the GAgP group than in the CP group (except the serum and salivary MDA levels and serum TAOC). Significant positive and negative correlations were observed between periodontal parameters and the MDA levels and TOS, TAOC, and OSI values (except serum MDA) (P <0.05). CONCLUSIONS The present findings suggest that an increased TOS and decreased TAOC, rather than LPO, play important roles in the pathology of periodontitis and are closely associated with clinical periodontal status. Furthermore, the OSI may be a useful and practical parameter for evaluating periodontal disease activity.
Fertility and Sterility | 2010
Suleyman Guven; Efnan Muci; Mesut A. Unsal; Esin Yulug; Ahmet Alver; Mine Kadioglu Duman; Ahmet Mentese
OBJECTIVE To determine the effect of CO(2) pneumoperitoneum on the ovaries in an experimental pneumoperitoneum model. DESIGN Experimental controlled study. SETTING University hospital. PATIENT(S) Sixteen adult female conventional rabbits. INTERVENTION(S) Group I (8 rabbits) was not subjected to intra-abdominal pressure (IAP). In group II (8 rabbits), IAP insufflation was performed at 12 mm Hg. In total, 60 minutes of pneumoperitoneum and 10 minutes of reperfusion were maintained. Ovarian blood flow (OBF) was studied using laser Doppler flowmetry. The time points of OBF measurements were as follows: OBFbaseline, 10 minutes before insufflation; OBF30min, 30 minutes after pneumoperitoneum; OBF60min, 60 minutes after pneumoperitoneum; and OBFreperfusion, 10 minutes after pneumoperitoneum desufflation. Mean OBF changes during CO(2) pneumoperitoneum (OBFmean) were also assessed. MAIN OUTCOME MEASURE(S) Blood perfusion units, tissue malondialdehyde values, and histopathologic damage scores. RESULT(S) In group II, mean OBF values were significantly lower than in group I, especially for OBF30min, OBF60min, OBFreperfusion, and OBFmean. The mean tissue malondialdehyde value for group II was significantly higher than in the control group (104.48 +/- 20.07 nmol/g vs. 64.12 +/- 8.77 nmol/g, respectively). Compared with group I, in group II histologic specimens of the ovaries had higher scores for follicular cell degeneration, vascular congestion, hemorrhage, and inflammatory cell infiltration. CONCLUSION(S) Pneumoperitoneum, even at normal IAP levels, leads to significant oxidative stress-induced biochemical and histologic damage to the ovaries.
Journal of Periodontology | 2014
Esra Baltacıoğlu; Malike Aslan Kehribar; Pınar Yuva; Ahmet Alver; Özlem Saraç Atagün; Erdem Karabulut; Ferda Alev Akalın
BACKGROUND In this study, the relationships between total oxidant status (TOS) and receptor activator of nuclear factor-κB ligand (RANKL) and osteoprotegerin (OPG) levels and RANKL/OPG ratios in serum and gingival crevicular fluid (GCF) are investigated in patients with chronic (CP) and generalized aggressive (GAgP) periodontitis. METHODS Thirty patients with CP, 30 patients with GAgP, and 28 periodontally healthy controls were included in the study. After clinical measurements and samplings, serum and GCF TOS, RANKL, and OPG levels were determined by a novel automatic colorimetric method and enzyme-linked immunosorbent assays. RESULTS Serum and GCF TOS, RANKL, and RANKL/OPG values were higher in the periodontitis groups compared with controls, and they were also higher in the GAgP group than the CP group (except serum and GCF RANKL). Furthermore, serum and GCF OPG concentrations were lower in the periodontitis groups than in controls. Strong positive and negative correlations were observed between the periodontal parameters TOS and bone resorption biomarkers. CONCLUSIONS The present results reveal that TOS, RANKL, and RANKL/OPG values are systemically and locally increased in periodontitis and that this increase is more evident in AgP than CP. These findings further suggest that oxidative stress is closely associated with the severity of periodontitis and bone resorption biomarkers.
Journal of Periodontology | 2009
Ferda Alev Akalın; Esra Baltacioglu; Ahmet Alver; Erdem Karabulut
Background: There is evidence of reduced antioxidant (AO) defense in periodontitis and pregnancy and adverse interactions between periodontitis and pregnancy. Methods: In this study, serum and gingival crevicular fluid (GCF) total AO capacity (TAOC) and superoxide dismutase (SOD) enzyme concentrations in pregnant patients with chronic periodontitis (CP) were compared to those in non-pregnant patients. Periodontal examinations were performed and GCF/ serum samples were obtained from 33 pregnant patients with CP (PCP), 18 pregnant patients with gingivitis (PG), and 21 periodontally healthy pregnant controls (P-controls), monitored in the first and third trimesters; 27 non-pregnant women with CP; and 25 non-pregnant control women. The concentrations of TAOC (automated measurement method) and SOD (spectrophotometric method) were determined. Results: Periodontal parameters were higher in pregnant patients versus non-pregnant patients and in the CP group compared to controls, whereas TAOC and SOD concentrations were lower (P<0.05). All parameters, except plaque index, increased in pregnant subjects in the third trimester compared to the first trimester, whereas TAOC and SOD levels decreased (P <0.05). Periodontal parameters were highest and TAOC and SOD levels were lowest in the PCP group in the third trimester (P<0.05). Conclusions: Systemic and local GCF AO levels decreased in pregnancy and periodontitis, and AO defense reached the lowest levels in the last phase of pregnancy, whereas periodontal status deteriorated. These results suggest that reduced AO capacity may be associated with adverse periodontitis-Dreanancv interactions, and each situation can be a provocative risk factor for the other.
Resuscitation | 2009
Suleyman Turedi; Abdulkadir Gunduz; Ahmet Mentese; Bengu Dasdibi; Suleyman Caner Karahan; Aynur Sahin; Gamze Tüten; Muge Kopuz; Ahmet Alver
BACKGROUND Early and accurate prediction of survival to hospital discharge following resuscitation after cardiac arrest (CA) is a major challenge. Our aim was to investigate the levels of ischemia-modified albumin (IMA) and malondialdehyde (MDA) in CA patients and whether IMA levels are valuable early marker of post-cardiopulmonary resuscitation prognosis in CA patients. METHODS We enrolled 52 in- or out-of-hospital CA patients, with 47 healthy volunteers as the control group (CG). Blood samples were taken for IMA and MDA measurement at the beginning or within 5 min of commencement of CPR. The patients were classified according to the Glasgow Outcome Score (GOS) into a poor outcome group (POG) and a good outcome group (GOG). RESULTS Mean IMA levels were higher in POG (0.25+/-0.07 ABSU) than in GOG (0.19+/-0.07 ABSU, p=0.002) and also than CG (0.16+/-0.04 ABSU, p=0.0001). The IMA levels were not significantly higher in GOG than in CG (p=0.32). The mean MDA levels in POG (0.77+/-0.27 nmol/ml) were comparable to the levels in GOG (0.75+/-0.18 nmol/ml, p>0.05), but were significantly higher than in CG (0.60+/-0.15 nmol/ml, p=0.001). MDA levels were not significantly higher in GOG than in CG (p=0.06). The optimum cut-off point for IMA maximizing sensitivity and specificity was 0.235 ABSU, with sensitivity of 65.8% and specificity of 78.6%. The corresponding +PV and -PV were 85.3% and 45.8%, respectively. CONCLUSION In conclusion, though the result may not be applied clinically in every patient, the ischemia-modified albumin may be a valuable prognostic marker in cardiac arrest patients following CPR.
Acta Obstetricia et Gynecologica Scandinavica | 2009
Suleyman Guven; Ahmet Alver; Ahmet Mentese; F. Ceylan Ilhan; Mustafa Calapoglu; Mesut A. Unsal
The aim of this prospective case‐control study was to determine the change in serum maternal ischemia‐modified albumin (IMA) during normal pregnancies. A total of 117 pregnant (first trimester (n = 24), second trimester (n = 34), and third trimester (n = 35)) and non‐pregnant healthy women (n = 23) were included. Maternal serum IMA, Malondialdehyde (MDA), and albumin levels were measured. Compared with non‐pregnant women, the cross‐sectional mean IMA levels in pregnant women were significantly increased, while the mean serum MDA and albumin levels were significantly decreased throughout pregnancy. Furthermore, a significant negative correlation between serum IMA and albumin levels (r = −0.354, p<0.001) was found, and there was a weak positive correlation between serum albumin and MDA levels (r = 0.334, p<0.001). Serum IMA, which has recently been developed as a clinical marker of ongoing myocardial ischemia, appears to be elevated in normal pregnancy. This may be due to the physiologic oxidative stress state of pregnancy.
The Scientific World Journal | 2013
Esin Yulug; Sibel Türedi; Ahmet Alver; Suleyman Turedi; Cemil Kahraman
This study investigated the probable protective effects of resveratrol (RES), an antioxidant, against methotrexate- (MTX-) induced testis damage. Twenty-four male Sprague Dawley rats were randomly divided into four groups: control, RES, MTX, and MTX + RES groups. Rats were sacrificed at the end of the experiment. Plasma and tissue malondialdehyde (MDA) levels, superoxide dismutase (SOD) and catalase (CAT) activity in tissue, testicular histopathological damage scores, and testicular and epididymal epithelial apoptotic index (AI) were evaluated. The MTX group had significantly higher plasma and tissue MDA levels and significantly lower SOD and CAT activity than those of the control group. In the MTX + RES group, plasma and tissue MDA levels decreased significantly and SOD activity rose significantly compared to the MTX group. The MTX group had significantly lower Johnsens testicular biopsy score (JTBS) values than those of the control group. JTBS was significantly higher in the MTX + RES group than in the MTX group. AI increased in the testis and epididymis in the MTX group and significantly decreased in the MTX + RES group. Our results indicate that RES has protective effects against MTX-induced testis damage at the biochemical, histopathological, and apoptotic levels.
Surgical Neurology | 2004
Haydar Usul; Ertugrul Cakir; Umit Cobanoglu; Ahmet Alver; Bekircan Peksoylu; Murat Topbas; Süleyman Baykal
BACKGROUND To investigate the effects of Tyrphostin Ag 556 on spinal cord ischemia reperfusion injury. METHODS The inhibition of tyrosine kinase may represent a novel approach in the treatment of spinal cord ischemia reperfusion injury. Recently, a family of tyrosine kinase inhibitors, the tyrphostins, has been successfully used in models of endotoxemia, peritonitis, and hypovolemic shock. MATERIALS AND METHODS Twenty-four Wistar rats were used in the study. Rats were divided into 4 groups of 6 animals. The groups were named as sham operated group, injury group, vehicle group, and treatment group. Clamping of the abdominal aorta was performed for 45 minutes with all of the groups except sham-operated group. All of the rats were sacrificed 24 hours after the operation for biochemical and ultrastructural studies. RESULTS Tyrphostin Ag 556 treatment was found effective on experimental spinal cord ischemia reperfusion injury. The Malondialdehyde (MDA) values of the treatment group were statistically significant lower then the other reperfusion injury groups. The histologic examination showed better cellular structure in the treatment group than the other reperfusion injury groups. The neurologic scores of the treatment group also improved after treatment. CONCLUSIONS Tyrphostin Ag 556 alters spinal cord ischemia reperfusion injury by inhibiting protein kinases. Further investigations will be required to determine the long-term effects of this drug.