Person: OKTAY, NİHAL ŞEHKAR
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OKTAY
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NİHAL ŞEHKAR
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Publication Open Access Comparison of the protective effect of alpha lipoic acid and quercetin in methotrexate- induced lung damage(2023-03-01) AK, ESİN; OKTAY, NİHAL ŞEHKAR; AK E., MUHAN A., ÇALIŞKAN Ş., OKTAY N. Ş.Objective: The aim of this experiment is to investigate and compare the effects of alpha lipoic acid (ALA) and quercetin (QUE) on methotrexate (MTX)-induced lung injury in rats. Method: Wistar Albino rats were distributed into control, MTX, MTX+ALA and MTX+QUE groups with each consisting of 6 rats. Except control group, MTX administrated to rats as a single dose (20 mg/kg) intraperitoneally (i.p.) on the first day. Saline (0.1 cc/100 gr/day, i.p.) was injected to rats in control and MTX groups for 5 days. In MTX+ALA and MTX+QUE groups, rats had injections of ALA (50 mg/kg/day, i.p.) and QUE (50 mg/kg/day, i.p.) for 5 days. After sacrification on day 6, lung tissues were excised out for histopathologic and biochemical investigation. Results: MTX group showed massive hemorrhage with edema in the interstitium, significant inflammatory cell infiltration, and severe alveolar destruction and vascular congestion. Additionally, significant increases in oxidative stress markers as malondialdehyde and sialic acid and significant decreases in antioxidants as glutathione, superoxide dismutase and catalase were detected at the tissue level in MTX group (p<0.0001, p<0.0001, p<0.0001, p=0.03 and p<0.0001, respectively). Both ALA and QUE treatment led to a prominent improvement in morphologic damage. Moreover, ALA and QUE resulted in the reversal of the alterations seen in the tissue oxidative damage markers and antioxidant activities as well. We could not reveal a significant difference between MTX+ALA and MTX+QUE group in terms of morphologic damage and biochemical markers of oxidative injury (p>0.05). Conclusion: Our study showed the similar protective effect of ALA and QUE in MTX induced lung damage. Further studies are warranted to verify the results of our outcome.Publication Metadata only The effect of a single application of different fluoride varnishes on enamel subsurface lesions in vitro(2022-04-01) ŞEN YAVUZ, BETÜL; YILMAZ, MÜESSER AHU; OKTAY, NİHAL ŞEHKAR; KARGÜL, BETÜL; Yildiz P. K., ŞEN YAVUZ B., YILMAZ M. A., OKTAY N. Ş., KARGÜL B.This in vitro study aimed to evaluate the therapeutic effect of different fluoride ion (F) varnish formulations for controlling the carious development of enamel subsurface lesions and the F release into artificial saliva for 2 hr, 24 hr, 48 hr, and 7 days. Artificial enamel carious lesions were created and divided into 6 groups (5 varnish groups and a control group). Varnishes were applied to enamel specimens and then the specimens were incubated in artificial saliva, with the artificial saliva replenished daily. Varnish was removed and lesions were remineralized in artificial saliva for 24 hr. Surface microhardness was measured three times: (i) initially, (ii) after creating the artificial enamel lesions, and (iii) after applying the varnishes. The F release was analyzed after 2 hr, 24 hr, 48 hr, and 7 days of exposure using an ion-selective electrode. Data were analyzed using a One-way Analysis of Variance with the Tukey-Kramer Multiple Comparisons test and the Kruskal-Wallis test with the Dunns Multiple Comparisons test. The highest percentage surface microhardness recovery was found for the treatment with the MI Varnish. According to the percentage surface microhardness recovery results, a statistically significant difference was found between the varnishes and the control group (p < 0.05 and < 0.001). All varnishes released measurable levels of fluoride ions. However, the release of F was the highest in the MI Varnish group (p < 0.01). Duraphat, Enamel Pro Varnish, and MI Varnish released the most F into artificial saliva. Calcium phosphate-based F varnishes improve the capacity of the enamel surface re -hardening. CPP containing F varnish had the highest release of F as compared to the other F releasing varnishes. Further in vivo investigations are also required to prove the clinical applications of the different ingredients containing varnishes.Publication Open Access FUTBOLCULARDA SLC6A4 PROMOTÖR POLİMORFİZMİNİN DAĞILIMI(2021-11-26) TACAL ASLAN, BESTE; Başak Funda EKEN;Tolga POLAT;Canan SERCAN DOĞAN;Beste Tacal ASLAN;Şehkar OKTAY;Korkut ULUCANİnsan psikolojisini etkileyen ve en önemli bir biyobelirteç olan serotonin, sporcunun atletik performansını da olumsuz yönde etkileyebilmektedir. Çalışmamızın amacı, sağlıklı profesyonel futbolcularda anksiyete ile bağlantılı SLC6A4 geni promotör bölgesinde “S” ve “L” allel dağılımının incelenmesidir. Çalışmamıza aktif olarak haftada en az 4 gün antrenman programı uygulayan 15-29 yaş arası 19 profesyonel futbolcu ve herhangi bir egzersiz programı uygulamayan (kontrol grubu) 45 birey katıldı. Gerekli etik kurul izinleri alındıktan sonra çalışma protokolunun sonuç ve çıktılarını anlatan onam formları katılımcılara imzalatıldı. Çalışmamıza katılan bireylerden daha sonra ağız içi epitel hücreleri alınarak DNA izolasyonu gerçekleştirildi. Tüm polimorfizmlerin genotiplemesi, polimeraz zincir reaksiyonu (PZR) metodu kullanılarak belirlendi. Çalışmamıza katılan futbolcularda SLC6A4 geninin LL, LS, SS genotiplerinin sayı ve yüzdeleri sırasıyla 11(%57,8), 4(%21,1), 4(%21,1) olarak belirlenmiştir. Çalışma kohortumuzda L alleli 26 (%68,4), S alleli ise 12 (%31,6) oranında gözlemlenmiştir. Çalışma grubumuzda SLC6A4 geninin promotör bölgesi incelendiğinde, LL genotipi baskın olarak bulunurken, L alleli de S alleline göre daha yüksek oranda bulunmuştur. Kontrol grubunda ise aynı genotip sayı ve yüzdeleri sırası ile 12 (%26,7), 24 (%53,3) ve 9 (%20) olarak belirlenmiştir. Kontrol grubundaki allelik dağılımı ise L alleli 48(%53,3), S alleli 42 (%46,7) olarak gözlenmiştir. Sporcu grubu ile kontrol grubu arasında genotip dağılımlarında (p=0,0001) bulunurken, allelik dağılımlarında (p=0,0425) bulunarak her iki grup arasında da istatiksel açıdan anlamlı farklılık saptanmıştır. Sonuç olarak çalışmamızda SLC6A4 promotör polimorfizmlerinin belirlenmesinin, sporcularda oluşan anksiyete ve bilişsel kaygı düzeyinin erken dönemde önlenmesine yardımcı olabileceği sonucuna varılmıştır.Publication Metadata only Is sialic acid a promising marker for periodontal diseases?(WOLTERS KLUWER MEDKNOW PUBLICATIONS, 2020) KURU, LEYLA; Oktay, S.; Bal, O. Ozoner; Kuru, L.; Yarat, A.; Noyan, U.Objective: Periodontal diseases are inflammatory chronic infections. Sialic acid (SA) is an acute phase reactant by itself. The aim of this study is to investigate the relationship between salivary and serum SA levels and clinical parameters in different forms of periodontal diseases. Subject and Methods: Systemically healthy subjects were included in the study; patients with chronic gingivitis (CG) (n = 10), chronic periodontitis (CP) (n = 10), and aggressive periodontitis (AgP) (n = 10), and ten volunteers with healthy periodontium as the control group. Total SA levels were determined by Warren's thiobarbituric acid method in whole saliva, parotis saliva, and serum samples of subjects before and 3 months after nonsurgical periodontal treatment. Full mouth clinical parameters including plaque index, gingival index, probing depth, and bleeding on probing were also recorded. Results: Before treatment, in both periodontitis groups salivary and serum SA levels were higher than those of controls (P = 0.001). Both salivary and serum SA levels decreased significantly in the patient groups after treatment (P < 0.001). Multiple comparisons of baseline clinical parameters in all groups revealed significant differences (P = 0.001) and these parameters decreased significantly on the 90th day (P < 0.01). There were positive correlations between SA levels and periodontal indices of the CG, CP, and AgP groups (P < 0.05). Conclusion: Our results suggest that SA level in both saliva and serum may be a potentially useful marker to determine inflammatory changes and investigate different forms of periodontal diseases.Publication Metadata only A guide to vitamins and their effects on diseases(Cambridge University Press, Cambridge (MA), USA , 2023-01-01) OKTAY, NİHAL ŞEHKAR; Oktay N. Ş.This book provides a contemporary, comprehensive and general review of vitamins and the role of vitamins in diseases. In the first part of the book, readers will be informed about fat-soluble and water-soluble vitamins, vitamin-like substances, how they work in the body, their absorption, storage, transport, their recommended daily allowances, deficiencies and toxicity. In the second part, readers will discover how vitamins affect several diseases, and learn about their mechanism of action in diseases. The second part will also explore vitamin related minerals such as calcium, phosphorus, magnesium, potassium, copper and zinc. The book is unique in that it reveals the mechanism of action of each vitamin in relation to conditions such as the metabolism, autoimmune diseases, degenerative systems, infectious diseases, and aging. This book serves as a brief but beneficial guide for academic institutions, health professionals, practitioners, medical and dentistry students, nutritionists and pharmacists.Publication Metadata only Genetic biomarkers of athletic performance(Nobel Tıp Kitapevleri, 2023-01-01) ULUCAN, KORKUT; TACAL ASLAN, BESTE; OKTAY, NİHAL ŞEHKAR; ULUCAN K., Yılmaz O. O., Eken B. F., POLAT T., Akcagıl Ö., TACAL ASLAN B., OKTAY N. Ş., ÖZKOÇAK G., ŞAKİROĞLU M.Publication Open Access Protective role of progesterone on lung injury induced by ischemia reperfusion of the lower limbs(2022-01-01) AK, ESİN; OKTAY, NİHAL ŞEHKAR; ÖZBEYLİ, DİLEK; AK, KORAY; AK E., OKTAY N. Ş., ÖZBEYLİ D., Muhan A., AK K.Objective: Remote lung injury is one of the most challenging issues in patients undergoing ischemia reperfusion (IR) injury of the lower limbs. We examined the role of progesterone (PG) on the remote injury of the lungs seen after IR of the lower limbs. Methods: Eighteen male Sprague Dawley rats were divided into three groups. (1) Control: rats had only two physiological saline injections intraperitoneally (i.p.) 2 h apart under general anesthesia. (2) IR: underwent 2 h tourniquet induced ischemia for both lower limbs followed by 2 h of reperfusion. Animals were injected with physiological saline (i.p.) before both ischemia and reperfusion. (3) IR + PG: rats underwent the same IR protocol as the IR group and were injected with PG (16 mg/kg, i.p.) before both ischemia and reperfusion. After reperfusion, rats were sacrificed, and lung tissues were taken out for histopathologic and biochemical analyses. Results: In IR + PG group, tissue levels of malondialdehyde and nitric oxide decreased significantly compared with the IR group (p<0.01). Similarly, glutathione level and superoxide dismutase and glutathione S-transferase activities significantly increased in the IR + PG group than in the IR group (p<0.05, p<0.01, and p<0.05, respectively). In light microscopy, reduced inflammatory cell infiltration, amelioration in alveolar structure, and mild vascular congestion in the parenchyma were seen in the IR + PG group. A significant improvement in histopathologic score was seen in the IR + PG group compared with the IR group (p<0.001). Conclusion: PG might be effective in attenuating remote injury of the lung in lower body IR via its antioxidant functionPublication Open Access Preliminary findings of the distribution of alpha-2-adrenergic receptor (ADRA2A) rs1800544 polymorphisms in kickboxing players(2021-12-01) TACAL ASLAN, BESTE; OKTAY, NİHAL ŞEHKAR; ULUCAN, KORKUT; Eken B. F., Savcı A. A., Polat T., Yılmaz Ö. Ö., Silar C., TACAL ASLAN B., OKTAY N. Ş., ULUCAN K.Objective: Adrenergic receptors play an important role in providing neurotransmitter release from the sympathetic nervous system and adrenergic neurons. The rs1800544 polymorphism in 3’-untranslated region of Alpha-2-Adrenergic Receptor (ADRA2A) is if caused by C>G tranversion at position –1291. In this study, we objective to analyze the rs1800544 distribution in kickboxing players. Methods: A total of 12 male players and 101 sedentary individuals (as a control group) participated in the study. Following DNA isolation, rs1800544 polymorphism of ADRA2A gene was determined by real-time polymerase chain reaction (Rt-PCR). Statistical analysis was carried out by chi-square test. Results: CC, CG and GG genotypes and percentages for rs1800544 polymorphism were analyzed as 5 (41,7%), 4 (33,3%) and 3 (25%), respectively. C allele was counted as 14 (58,3%) and G allele as 10 (41,7%). In the control group CC, CG and GG were found as 34 (33,6%), 53 (52,5%), 14(13,9%), respectively. C allele was counted as 121 (60%) and G allele as 81 (40%). When we compare athletes and controls in the terms of genotypes, we detected no statistically significant difference (p>0,3940). For the allele comparison, we detected no significant difference between groups (p>0,0871). Conclusion: Determination of gene combinations in athletes is of great importance for determination of the effect of genetic factors in athletic performance. In our cohort, CC genotype was more frequently found, and C allele was also higher in players. We think that the effect of ADR2A2 gene on athletic performance might be determined more clearly by the fact that this study is an example of similar studies involving higher numbers of subjects.Publication Metadata only Biochemical investigation of methotreaxate-induced oxidative stress on liver tissue(2023-11-23) OKTAY, NİHAL ŞEHKAR; Savaş Ş., Oktay N. Ş.