Hitit Üniversitesi Kurumsal Akademik Arşivi
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Comments on the relationship between microRNA-155-5p and postoperative inflammatory markers in children with acute suppurative appendicitis, and its role in predicting postoperative complications
No full textDear Editor,
I read with interest the study by Dr. Duan et al.1 titled “The relationship between microRNA-155-5p and postoperative inflammatory markers in children with acute suppurative appendicitis and its role in predicting
postoperative complications” published in The Turkish Journal of Pediatrics
Relationship between the presence of non-dipper heart rate and ventricular arrhythmias in patients with isolated hypertension
No full textObjective: In healthy individuals, the increase in parasympathetic tone during nighttime leads to a decrease in heart rate. When this decrease does not occur or happens minimally, it is an indicator of increased sympathetic activity. This condition could be an important mechanism that may increase the susceptibility to ventricular arrhythmias, especially in hypertensive individuals. The aim of this study is to compare the frequency of ventricular arrhythmias and other clinical parameters between cases with and without a heart rate decrease during the night in isolated hypertensive patients monitored by a rhythm Holter. Materials and Methods: A total of 229 isolated hypertensive patients (mean age 58.2±12.5 years, 89 (38.9%) male) who underwent transthoracic echocardiography, rhythm Holter, and amulatory blood pressure monitoring and applied to the Department of Cardiology at Hitit University Faculty of Medicine in the last 12 months up until March 2025 were included in this study. The cases included in the study were divided into two groups based on their nighttime heart rate decrease in the rhythm Holter: the 'dipper' group, with a decrease of 10% or more, and the 'non-dipper' group, with a decrease of less than 10%. The primary comparisons were made between these two groups. Then, according to the Lown classification, patients in the low Lown class (Lown 0) were compared with those in the high Lown class (Lown 1-4), and the same comparisons were repeated between these two groups. Parameters that were significantly different between the Lown class 0 and Lown class 1-4 groups were included in multivariate analysis, aiming to identify independent and significant parameters that may influence the development of cardiac arrhythmias in isolated hypertensive patients. Results: In Holter rhythm analyses, 170 patients (mean age 57.8±12.2 years, 66 [38.8%] male) with a nocturnal heart rate decrease of ≥10% were classified as the dipper group, while 59 patients (mean age 59.3±13.4 years, 23 [29%] male) with a decrease of <10% were classified as the non-dipper group. There was no significant difference between the dipper and non-dipper groups in terms of baseline demographic parameters, laboratory values, or medications used. When transthoracic echocardiographic parameters were compared between the two groups, interventricular septal thickness (11.9±1.6 vs. 11.3±1.4 mm; p=0.005), posterior wall thickness (11.7±1.6 vs. 11.3±1.6 mm; p=0.047), left ventricular (LV) mass (193.8±47.1 vs. 174.7±48.6 g; p=0.009), LV mass index (103.9±26.2 vs. 95.3±28.2 g/m²;VIII p=0.040), presence of LV hypertrophy (78% vs. 60.6%; p=0.016), and presence of concentric hypertrophy (55.9% vs. 37.6%; p=0.014) were significantly higher in patients with non-dipper heart rate compared to those with dipper heart rate. When Holter rhythm parameters were compared between the two groups, both the number of ventricular extrasystoles (1039 [8– 1600] vs. 120 [0–321] beats; p<0.001) and the number of atrial premature beats (451 [3– 1366] vs. 129 [0–445] beats; p<0.001) were found to be significantly higher in the non-dipper heart rate group. Comparing the Lown classification between the two groups, arrhythmia frequency was observed to be higher in patients with non-dipper heart rate (p<0.001). Based on Lown classification, 139 patients (mean age 57.2±13.4 years, 58 [41.7%] male) were categorized in Lown class 0, and 90 patients (mean age 59.8±10.8 years, 31 [34.4%] male) in Lown class 1–4. No significant differences were observed between these groups in terms of baseline demographic characteristics, laboratory findings, or medications used. However, echocardiographic parameters such as interventricular septal thickness (11.8±1.6 vs. 11.3±1.5 mm; p=0.005), posterior wall thickness (11.7±1.6 vs. 11.2±1.6 mm; p=0.011), LV mass (187.8±47.2 vs. 174.3±49.3 g; p=0.040), LV mass index (102.8±26.2 vs. 94.1±28.6 g/m²; p=0.021), presence of LV hypertrophy (73.3% vs. 59.7%; p=0.036), and presence of concentric hypertrophy (52.2% vs. 36%; p=0.015) were significantly higher in patients in the Lown class 1–4 group compared to the Lown class 0 group. Additionally, 24-hour average systolic blood pressure (p=0.015), daytime average systolic blood pressure (p=0.014), and nighttime average systolic blood pressure (p=0.011) were significantly higher in the Lown class 1–4 group among ambulatory blood pressure monitoring parameters. When rhythm Holter parameters were compared between these two groups, both the number of ventricular extrasystoles (908 [122–2509] vs. 0 [0] beats; p<0.001) and the number of atrial premature beats (671 [122–1863] vs. 52 [0–360] beats; p<0.001) were found to be significantly higher in the Lown class 1–4 group. Furthermore, non-dipper heart rate status was more frequently observed in the Lown class 1–4 group (89.9% vs. 50%; p<0.001). In correlation analysis, a weak but statistically significant negative correlation was detected between percentage change in heart rate and both LV mass (r= -0.256; p=0.018) and LV mass index (r= -0.243; p=0.031). In multivariate analysis, the presence of concentric hypertrophy (Relative Risk: 2.879; 95% Confidence Interval: 1.843–9.829; p=0.041) and a nocturnal heart rate decrease of less than 10% (Relative Risk: 9.616; 95% Confidence Interval: 4.563–20.261; p=0.001) were identified as independent predictive parameters for the development of cardiac arrhythmias.Amaç: Sağlıklı bireylerde gece saatlerinde artan parasempatik tonus ile kalp hızı düşerken, bu düşüşün olmaması ya da minimal düzeyde gerçekleşmesi, artmış sempatik aktivitenin bir göstergesidir. Bu durum, özellikle hipertansif bireylerde ventriküler aritmilere yatkınlığı artırabilecek önemli bir mekanizma olabilir. Bu çalışmada izole hipertansif hastalarda ritim holterde gece düşmeyen kalp hızı olan ve olmayan olgular arasında ventriküler aritmi sıklığının ve diğer klinik parametrelerin karşılaştırılması amaçlanmıştır. Gereç ve Yöntem: Bu çalışmaya Mart 2025 tarihine kadar son 12 ay içerisinde Hitit Üniversitesi Tıp Fakültesi Kardiyoloji Anabilim Dalı'na başvuran transtorasik ekokardiyografi yapılan, ritim ve tansiyon Holter takılan 229 izole hipertansif hasta (ortalama yaş 58,2±12,5 yıl , 89 (% 38.9) erkek) alınmıştır. Çalışmaya dahil edilen olgular ritim holterinde gece kalp hızında %10 ve üzerinde düşüş olan olgular dipper grubu, %10 dan daha az düşüş olanlar ise non-dipper grubu olmak üzere üzere iki gruba ayrılmıştır. Temel karşılaştırmalar bu iki grup arasında yapılmıştır. Sonrasında Lown sınıflamasına göre düşük Lown sınıfında (Lown 0) olan hastalar ile yüksek Lown sınıfında (Lown 1-4) olan hastalar iki gruba ayrılarak aynı karşılaştırmalar bu iki grup arasında da tekrarlanmıştır. Lown sınıf 0 grubu ile Lown sınıfı 1-4 grubu arasında istatistiksel olarak anlamlı olan parametreler çok değişkenli analiz ile değerlendirilerek bağımsız öngördürücülerin belirlenmesi amaçlandı. Bulgular: Hastalar ritim Holter analizlerinde kalp hızında gece %10 ve üzerinde düşüş olan 170 hasta (ortalama yaş 57,8±12,2yıl , 66 (% 38,8) erkek) dipper grubu, %10'dan daha az düşüş olan 59 hasta (ortalama yaş 59,3±13,4 yıl , 23 (% 29) erkek) ise non-dipper grubu olarak belirlendi. Dipper ve Non-Dipper grupları arasında bazal demografik parametreleri, laboratuar parametreleri kullandıkları ilaçlar açısından anlamlı fark izlenmedi. İki grup arasında transtorasik ekokardiyografi parametreleri karşılaştırıldığında interventriküler septal kalınlık (11,9±1,6 vs. 11,3±1,4 mm; p=0,005 ), arka duvar kalınlığı (11,7±1,6 vs. 11,3±1,6 mm; p=0,047 ), sol ventrikül kitlesi (193,8±47,1 vs. 174,7±48,6 gr; p=0,009 ), sol ventrikül kitle indeksi (103,9±26,2 vs. 95,3±28,2 gr/m2; p=0,040 ), sol ventrikül hipertrofisi varlığı (%78 vs. %60,6; p=0,016 ) ve konsentrik hipertrofi varlığı (%55,9 vs. %37,6 ; p=0,014 ) nondipper kalp hızı olan hastalarda dipper kalp hızı olan hastalara göre anlamlı olarak daha yüksek olduğu görüldü. İki grup arasında ritim Holter parametleri karşılaştırıldığında hem ventriküler ekstra sistol sayısı (1039 (8-1600) vs. 120 (0-321) atım; p<0,001) hem de atriyal erken atım sayısının (451 (3-1366) vs. 129 (0-445) atım; p<0,001) non-dipper kalp hızı grubunda anlamlı olarak daha yüksek olarak tespit edildi. İki grup arasında Lown sınıflarıVI karşılaştırıldığında non-dipper kalp hızı olan hastalarda aritmi sıklığının daha yüksek olduğu gözlendi (p<0,001). Hastalar Lown sınıflarına göre sınıflandırıldığında, Lown sınıf 0 grubunda 139 hasta (ortalama yaş 57,2±13,4 yıl , 58 (%41,7) erkek), Lown sınıfı 1-4 grubunda ise 90 hasta (ortalama yaş 59,8±10,8 yıl , 31 (%34,4) erkek) tespit edildi. Bu gruplar arasında da bazal demografik parametreler, laboratuar parametreleri ve kullandıkları ilaçlar açısından anlamlı fark gözlenmezken, ekokardiyografi parametrelerden interventriküler septal kalınlık (11,8±1,6 vs. 11,3±1,5 mm; p=0,005 ), arka duvar kalınlığı (11,7±1,6 vs. 11,2±1,6 mm; p=0,011 ), sol ventrikül kitlesi (187,8±47,2 vs. 174,3±49,3 gr; p=0,040 ), sol ventrikül kitle indeksi (102,8±26,2 vs. 94,1±28,6 gr/m2; p=0,021 ), sol ventrikül hipertrofisi varlığı (%73,3 vs. %59,7 ; p=0,036 ) ve konsentrik hipertrofi varlığı (%52,2 vs. %36 ; p=0,015 ) Lown sınıfı 1-4 grubu hastalarda Lown sınıf 0 grubu hastalara göre anlamlı olarak daha yüksek olduğu görüldü. Ayrıca tansiyon Holter parametlerinden 24-saatlik ortalama sistolik kan basıncı (p=0,015), gündüz ortalama sistolik kan basıncı (p=0,014) ve gece ortalama sistolik kan basıncı (p=0,011) Lown sınıfı 1-4 grubunda anlamlı olarak daha yüksek olduğu tespit edildi. İki grup arasında ritim Holter parametleri karşılaştırıldığında hem ventriküler ekstra sistol sayısı (908 (122-2509) vs. 0 (0) atım; p<0,001) hem de atriyal erken atım sayısının (671 (122-1863) vs. 52 (0-360) atım; p<0,001) Lown sınıfı 1-4 grubunda anlamlı olarak daha yüksek olarak tespit edildi. Ayrıca non-dipper kalp hızı durumunun Lown sınıfı 1-4 grubunda daha fazla karşılaşıldığı (89,9 vs. 50 % ; p<0,001) gözlendi. Korelasyon analizinde sol ventrikül kitlesi ile kalp hızı değişim yüzdesi arasında ve sol ventrikül kitle indeksi ile kalp hızı değişim yüzdesi arasında zayıf fakat istatistiksel olarak anlamlı negatif korelasyon tespit edildi. (sırasıyla r= -0,256 ; p=0,018 ve r= -0,243 ; p=0,031). Çok değişkenli analiz sonucunda konsentrik hipertrofi varlığı (Rölatif Risk: 2,879 %95 Güven Aralığı: 1,843-9,829 ; p=0,041) ve gece kalp hızında beklenen fizyolojik düşüşün olmaması, kardiyak otonomik disfonksiyonun bir göstergesi olarak değerlendirilmiş ve bu durum, Lown sınıflamasına göre daha ileri düzeyde ventriküler aritmi varlığı ile anlamlı düzeyde ilişkilendirilmiştir
Research of the synthesis, structural characterization and biological activities of mixed ligand complexes containing aniscic acid nicotinamide/N,N'-diethylnicointinamide/1,10-phenathroline ligands of some transition metal cations
No full textAnisic acid (p-methoxybenzoic acid) was first synthesized in 1841 by French chemist and scientist Auguste Cahours through the oxidation of anethole (C10H12O). Anethole is an essential oil found as an active ingredient in anise. The anisic acid synthesized by Cahours was purified from anise extract by recrystallization using diluted nitric acid. Anisic acid is also referred to as p-methoxybenzoic acid or sometimes dragonic acid.
Anisic acid is frequently used in the pharmaceutical industry as a raw material for drugs, as a flavoring and preservative in the food industry, as a preservative in the cosmetic industry due to its antimicrobial properties, and in the fragrance and plastic industries.
Moreover, anisic acid, being an important intermediate in organic chemistry, is used as a starting material in various reactions due to its methoxy group and carboxylic acid group. These broad applications make anisic acid an important compound in both industrial chemistry and consumer products.
In this thesis study, a total of 14 mixed-ligand complexes containing Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) transition metals, along with p-methoxybenzoic acid and the ligands nicotinamide (NA)/N,N-diethylnicotinamide (DENA)/1,10-phenanthroline (PHEN), were synthesized for the first time. The molecular formulas of the synthesized complexes are proposed as follows:
[Mn(C8H7O3)2(C6H6N2O)2(H2O] (I)
[Co(C8H7O3)2(C6H6N2O)2(H2O)2].H2O (II)
[Ni(C8H7O3)2(C6H6N2O)2(H2O)2] (III)
[Cu(C8H7O3)2(C6H6N2O)2(H2O)] (IV)
[Zn(C8H7O3)2(C6H6N2O)2(H2O)2] (V)
[Mn(C8H7O3)2(C10H14N2O)2(H2O)2] (VI)
[Co(C8H7O3)2(C10H14N2O)2(H2O)2].2H2O (VII)
[Ni(C8H7O3)2(C10H14N2O)2(H2O)2] (VIII)
[Cu(C8H7O3)2(C10H14N2O)2(H2O)] (IX)
[Zn(C8H7O3)2(C10H14N2O)2(H2O)2].H2O (X)
[Co(C8H7O3)2(C12H8N2)].H2O (XI)
[Ni(C8H7O3)2(C12H8N2)].H2O (XII)
[Cu(C8H7O3)2(C12H8N2)(H2O)].2H2O (XIII)
[Zn(C8H7O3)2(C12H8N2)(H2O)] (XIV)
The structures of the synthesized complexes were analyzed by elemental analysis, FT-IR spectroscopy, single crystal X-ray diffraction diffractometry, magnetic susceptibility and melting point determination methods. Thermal analysis (TGA/DTA/DrTGA) methods were also used for the characterization of thermal decomposition behaviors of the molecules. Finally, the biological activities of the complex molecules whose structures were characterized were investigated in cell culture medium.Anisik asit (p-metoksibenzoik asit) ilk olarak 1841 yılında Fransız kimyager ve bilim insanı Auguste Cahours tarafından anetolün (C10H12O) oksitlenmesinden sentezlenmiştir. Anetol anasonda etken madde olarak bulunan bir yağdır. Cahours tarafından sentezlenen anisik asit, seyreltilmiş nitrik asitle yeniden kristallendirme yöntemi ile anason özünden saflaştırılmıştır. Anisik asit p-metoksibenzoik asit olarak, ticari olarak da dragonik asit isimleriyle de anılmaktadır.
Anisik asit farmasötik endüstride ilaçların ham maddesi olarak, gıda endüstrisinde tatlandırıcı ve koruyucu olarak, kozmetik endüstrisinde antimikrobiyal özelliklerinden dolayı koruyucu bir madde olarak, aroma ve koku endüstrisinde ve plastik endüstrisinde sıklıkla kullanılmaktadır.
Ayrıca organik kimyada önemli bir ara madde olan anisik asit, özellikle metoksi grubu ve karboksilik asit içermesi nedeniyle çeşitli reaksiyonlarda başlangıç maddesi olarak kullanılır. Bu geniş kullanım alanları, anisik asidin hem endüstriyel kimyada hem de tüketici ürünlerinde önemli bir bileşik olmasını sağlar.
Bu tez çalışması kapsamında, Mn(II), Co(II), Ni(II), Cu(II) ve Zn(II) geçiş metallerinin p-metoksibenzoik asit ile nikotinamid (NA)/N,N-dietilnikotinamid (DENA)/1,10-fenantrolin (PHEN) ligandlarını içeren karışık ligandlı 14 adet kompleks ilk defa sentezlenmiştir. Sentezlenen komplekslerin molekül formüllerinin aşağıdaki gibi olduğu önerilmektedir:
[Mn(C8H7O3)2(C6H6N2O)2(H2O)] (I)
[Co(C8H7O3)2(C6H6N2O)2(H2O)2].H2O (II)
[Ni(C8H7O3)2(C6H6N2O)2(H2O)2] (III)
[Cu(C8H7O3)2(C6H6N2O)2(H2O)] (IV)
[Zn(C8H7O3)2(C6H6N2O)2(H2O)2] (V)
[Mn(C8H7O3)2(C10H14N2O)2(H2O)2] (VI)
[Co(C8H7O3)2(C10H14N2O)2(H2O)2].2H2O (VII)
[Ni(C8H7O3)2(C10H14N2O)2(H2O)2] (VIII)
[Cu(C8H7O3)2(C10H14N2O)2(H2O)] (IX)
[Zn(C8H7O3)2(C10H14N2O)2(H2O)2].H2O (X)
[Co(C8H7O3)2(C12H8N2)].H2O (XI)
[Ni(C8H7O3)2(C12H8N2)].H2O (XII)
[Cu(C8H7O3)2(C12H8N2)(H2O)].2H2O (XIII)
[Zn(C8H7O3)2(C12H8N2)(H2O)] (XIV)
Sentezlenen komplekslerin yapıları elemental analiz, FT-IR spektroskopisi, tek kristal X-ışını kırınımı difraktometresi, manyetik duyarlılık ve erime noktası tayini yöntemleriyle analiz edilmiştir. Moleküllerin termal bozunma davranışlarının karakterizasyonu için de termal analiz (TGA/DTA/DrTGA) metodları kullanılmıştır. Yapıları karakterize edilen kompleks moleküllerin son olarak biyolojik aktiviteleri hücre kültürü ortamında incelenmiştir
Comparative phonology study of the dialects of Çorum, Çankırı and Amasya provinces
No full textDialect studies have an important place in the research areas of Turkish language. Studies
conducted in the form of compiling and examining the dialect features of a region in terms of
phonetics are very important in revealing the language features of a region. As a result of these
studies, the features of Turkish language that are on the verge of disappearing can be included
in the language memory again. By examining dialects comparatively, linguistic differences and
similarities between regions can be determined. As a result of these studies, the phonetics,
morphology and syntax features of Turkish dialects in Turkey can be revealed and a significant
contribution can be made to dialect studies.
In this study; In order to contribute to Turkish dialect studies in Turkiye, the dialects of Çorum,
Çankırı and Amasya provinces were examined in terms of phonetics comparatively. The study
consists of three main sections: phonetics, vowel and consonant presence related to the
examined dialect regions and phonetic events in the examined dialect regions.
In the introduction part of the thesis, general information about the purpose, scope, method
and literature review of our study is given. After the necessary definitions regarding dialects
were made, the historical course of Turkish dialect studies was examined. After the regional
classification of Turkish dialects in Turkiye was made, information about the dialect
characteristics of these regions was given. After this information, the general characteristics of
the selected region were briefly mentioned. In the examination section of the thesis, vowels,
consonants and phonetic events were given under two main headings. In these sections;
Çorum, Çankırı and Amasya dialects were examined by taking the previously made master's
and doctoral theses as sources. The vowels and consonants in the examined dialects were given
with transcription signs. These dialects were examined in detail and their similarities and
differences in terms of phonetics were revealed. The examples given regarding phonetic events
were written with their equivalents in standard Turkish. The characteristics that are
characteristic for a dialect region were also emphasized.
Key Terms: Turkiye Turkish, Çorum Dialect, Çankırı Dialect, Amasya Dialect, Comparative
Phonetics.
Science Code: 14701Ağız araştırmaları, Türk dilinin araştırma alanları içerisinde önemli bir yer tutmaktadır. Bir
yöreye ait ağız özelliklerinin derlenmesi ve ses bilgisi açısından incelenmesi şeklinde yapılan
çalışmalar, bir yöreye ait dil özelliklerinin ortaya çıkmasında çok önemlidir. Bu çalışmalar
sonucunda Türk dilinin kaybolmaya yüz tutmuş özellikleri tekrar dil hafızasına dâhil
edilebilmektedir. Ağızların karşılaştırmalı olarak ele alınmasıyla da bölgeler arasındaki dilsel
farklılık ve benzerlikler tespit edilebilmektedir. Bu çalışmaların sonucunda Türkiye Türkçesi
ağızlarının ses bilgisi, biçim ve söz dizimi özellikleri ortayı koyularak ağız araştırmalarına
önemli bir katkı sağlanabilir.
Bu çalışmada; Türkiye Türkçesi ağız araştırmalarına katkı sunmak amacıyla Çorum, Çankırı ve
Amasya illeri ağızları, karşılaştırmalı olarak ses bilgisel açıdan incelenmiştir. Çalışmamız; ses
bilgisi, incelenen ağız bölgeleriyle ilgili ünlü ve ünsüz varlığı ve incelenen ağız bölgelerindeki
ses olayları olmak üzere üç ana bölümden oluşmaktadır.
Tezin giriş kısmında çalışmamızın amacı, kapsamı, yöntemi ve literatür taraması ile ilgili genel
bilgilere yer verilmiştir. Ağızlarla ilgili gerekli tanımlar yapıldıktan sonra Türkiye Türkçesi ağız
çalışmalarının tarihî seyri incelenmiştir. Türkiye Türkçesi ağızlarının bölgesel sınıflandırması
yapıldıktan sonra bu bölgelerin ağız özellikleri hakkında bilgilere yer verilmiştir. Bu bilgilerden
sonra da seçilen bölgenin genel özelliklerinden kısaca bahsedilmiştir.
Tezin inceleme kısmında ünlüler, ünsüzler ve ses olayları iki ana başlık altında verilmiştir. Bu
bölümlerde; Çorum, Çankırı ve Amasya ağızları daha önce yapılan yüksek lisans ve doktora
tezleri kaynak alınarak incelenmiştir. Ele alınan ağızlardaki ünlüler ve ünsüzler çeviri yazı
işaretleriyle birlikte verilmiştir. Bu ağızlar detaylıca incelenerek ses bilgisi yönünden benzerlik
ve farklılıkları ortaya konulmuştur. Ses olayları ile ilgili verilen örnekler standart Türkçedeki
karşılıklarıyla yazılmıştır. Bir ağız bölgesi için karakteristik olan özelliklerin üzerinde ayrıca
durulmuştur.
Anahtar Kavramlar: Türkiye Türkçesi Ağızları, Çorum Ağzı, Çankırı Ağzı, Amasya Ağzı,
Karşılaştırmalı Ses Bilgisi.
Bilim Kodu: 1470
Investigation of the effect of surfactants on the long-term macrodisperson of graphene
No full textGraphene-based nanofluids have become a significant research topic in various scientific and technological fields in recent years due to their exceptional thermal, electrical, and mechanical properties. These nanofluids offer potential solutions in numerous areas such as energy storage, electronics, biomedical applications, and heat transfer, owing to their high surface area and unique structural properties. However, obtaining stable dispersions of graphene in aqueous media is a critical factor that directly affects the material's usability in practical applications.
In this study, the preparation and characterization of stable graphene dispersions in water using different surfactants were aimed. Cationic didodecyldimethylammonium bromide and cetylpyridinium bromide surfactants played a role in enhancing the physical stability by enabling the homogeneous distribution of graphene particles in the aqueous medium. The stability and properties of the prepared dispersions were comprehensively analyzed using advanced characterization techniques such as UV-VIS spectroscopy, zeta potential measurements, zeta-sizer analysis, X-ray diffraction, Raman spectroscopy, and transmission electron microscopy. Additionally, the antimicrobial effects of these graphene dispersions on different bacterial species were evaluated, revealing the material's potential for biomedical applications.Grafen bazlı nanoakışkanlar; olağanüstü termal, elektriksel ve mekanik özellikleri sayesinde son yıllarda çok çeşitli bilimsel ve teknolojik alanlarda önemli bir araştırma konusu haline gelmiştir. Bu nanoakışkanlar, yüksek yüzey alanı ve benzersiz yapı özellikleri sayesinde enerji depolama, elektronik, biyomedikal uygulamalar ve ısı transferi gibi pek çok alanda potansiyel çözümler sunmaktadır. Ancak grafenin sulu ortamda kararlı dispersiyonlarının elde edilmesi, bu materyalin pratik uygulamalarda kullanılabilirliğini doğrudan etkileyen kritik bir faktördür. Bu çalışmada, grafenin su ortamında farklı yüzey aktif maddeler kullanılarak stabil dispersiyonlarının hazırlanması ve karakterizasyonu amaçlanmıştır. Katyonik yüzey aktif maddeler olan didodesildimetilamonyum bromür ve setilpiridinyum bromür, grafen parçacıklarının su içinde homojen şekilde dağılmasını sağlayarak fiziksel stabiliteyi artırmada rol oynamıştır. Hazırlanan dispersiyonların stabilitesi ve özellikleri, UV-VİS spektroskopisi, zeta potansiyel ölçümleri, zeta boyut analizi, X-ışını kırınımı, Raman spektroskopisi ve geçirimli elektron mikroskobu gibi ileri karakterizasyon teknikleri kullanılarak kapsamlı biçimde incelenmiştir. Ayrıca, bu grafen dispersiyonlarının farklı bakteriyel türler üzerindeki antimikrobiyal etkileri de değerlendirilmiş, böylece materyalin biyomedikal uygulamalar açısından taşıdığı potansiyel incelenmiştir
Investigation of Physical and Cognitive Performance of Athletes
No full textThis study aims to examine the relationship between physical performance levels and cognitive functions of male athletes aged 18-25 years competing in the Turkish Hockey Indoor 1st League. 45 athletes participated in the study, balance, flexibility and vertical jump tests and D2 Attention Test were applied. In addition to descriptive statistics, independent samples t-test, one-way analysis of variance (ANOVA) and Pearson correlation analysis were used to analyze the data. The results revealed that attention levels did not differ significantly according to age, education, sport experience and position (p>0.05). While there was no significant relationship between physical performance variables and attention, only vertical jump values showed a significant difference between the positions (p<0.05). In addition, positive and significant correlations were observed between the sub-dimensions of the attention test. In this context, it was concluded that not only physical criteria but also cognitive skills should be systematically included in the performance evaluations of hockey athletes
Quercetin Enhances Chemosensitivity in Gemcitabine-Treated MCF-7 Breast Cancer Cells
No full textObjective: Breast cancer remains a major contributor to cancer-related mortality among women globally, posing a major challenge to women's health. Although chemotherapeutic agents such as gemcitabine (GEM) are widely used, their effectiveness is often limited by drug resistance and adverse side effects. Natural compounds like quercetin (Quer), a flavonoid with known anticancer properties, may enhance the chemosensitivity of cancer cells and reduce the toxicity associated with conventional chemotherapy. This study aimed to evaluate the combined effect of GEM and Quer on the viability, oxidative stress, and cytotoxicity in MCF-7 human breast cancer cells. Methods: MCF-7 cells were treated with varying concentrations of GEM (100-500 mu M) or Quer (25-400 mu M) for 24 hours to determine the minimum effective doses for combination treatment. Cell viability was assessed using standard viability assays. Intracellular reactive oxygen species (ROS) and malondialdehyde (MDA) levels were measured as indicators of oxidative stress and lipid peroxidation, respectively. Results: GEM alone did not significantly affect MCF-7 cell viability, while Quer at 50 mu M showed a modest cytotoxic effect. However, the combination of GEM and Quer significantly reduced cell viability and increased ROS and MDA levels (p < 0.05), indicating enhanced oxidative stress and cytotoxicity. Neither agent alone significantly altered ROS or MDA levels. Conclusion: The combination of GEM and Quer synergistically enhances cytotoxicity in MCF-7 breast cancer cells through oxidative stress mechanisms. These findings suggest that integrating natural compounds like quercetin into conventional chemotherapy regimens may offer more effective and less toxic treatment strategies for breast cancer, contributing to improved therapeutic outcomes and quality of life in women
A scoping review of the health effects of fermented foods in specific human populations and their potential role in precision nutrition: current knowledge and gaps
No full textBackground: Diets and specific foods have a significant impact on health, and individual responses to nutritional factors vary. This variability among humans can be considered a basis for developing personalized or precision nutrition. Fermented foods (FF) contain a wide range of macro- and micronutrients, bioactive compounds, and live or dead microorganisms. FF represent a diverse range of products and have garnered significant interest due to their potential health benefits. However, consistent evidence remains limited, possibly due to heterogeneity in individual responses. Objectives: The objective of this review is to assess and compile existing evidence on the variable responses of populations to FF and to determine whether FF could be integrated into a precision nutrition strategy. Design: Interventional and observational human studies were systematically collected. The publication identified the main factors likely to contribute to variable responses to FF across all health outcomes. The question was systematically addressed to assess the available evidence and identify knowledge gaps, guiding future research. A pragmatic approach was employed, following EFSA health claim guidelines, which require an assessment of food characteristics and mechanisms of action, as well as conducting a systematic search of human interventional studies. A similar approach was used to analyze data extracted from observational studies. The population included all humans (healthy and non-healthy, of all ages), encompassing both observational and interventional studies. The intervention consisted of the ingestion of any FF, while the control was defined as the absence or lower consumption of FF or consumption of a corresponding non-FF. Outcomes included all markers of the population's health status. Results: The main factors contributing to variable responses to FF across all health outcomes were related to initial phenotypic characteristics (biological sex, geographical origin, hormonal status, and age), baseline health status [metabolic syndrome [MetS], chronic metabolic pathologies, cancer, and psychological disorders], and genetic background. Additionally, since the gut microbiota is person-specific and influences metabolic responses, particular attention was paid to its functions and role in the variability of population responses to FF. Conclusion: Collectively, this review represents a first step toward evaluating the feasibility of using FF in tailored nutritional strategies. Systematic review registration: https://osf.io/69d3f/overview
Computational analysis of the Au-catalyzed isomerization of alkynyl epoxides to furans
No full textThe isomerization of epoxides to furans, accompanied by gold(III), was elucidated theoretically. The structural properties of the transition states (TSs) and intermediates were studied with B3LYP or M06-2X hybrid density functionals in various solvents. The electronic features of the substituents bonded to the alkyne part were significant in forming the furan rings. Details of the furan formations were explored, and the reactant's natural population analysis was conducted. Additionally, this computational work proposed an alternative mechanism for synthesizing oxetene rings
Body Composition Analysis in Obstructive Sleep Apnea: A Cross-Sectional Study Using Bioelectrical Impedance Analysis
No full textIntroduction Obstructive sleep apnea (OSA) is a prevalent disorder characterized by recurrent upper airway collapse, resulting in intermittent hypoxia and sleep fragmentation. While obesity is a major risk factor, traditional markers such as body mass index (BMI) inadequately reflect the complex interplay of body composition in OSA pathogenesis. This study aimed to investigate the predictive value of body composition parameters assessed by bioelectrical impedance analysis (BIA) for OSA.Methods In this cross-sectional single-center study, 78 patients diagnosed with OSA by polysomnography (PSG) and 78 age-, gender-, and BMI-matched controls without OSA were analyzed. BIA was used to assess fat distribution, muscle mass, and body water composition. Logistic regression analyses were performed to identify independent predictors of OSA.Results Compared to controls, the OSA group had significantly higher lean mass, trunk fat percentage, and total body water. Multivariable logistic regression identified body fat mass (OR = 1.06), visceral fat area (OR = 0.83), and total body water (OR = 1.10) as independent predictors of OSA. Notably, total body water had the strongest association with OSA risk, independent of traditional obesity metrics.Conclusion BIA-derived body composition analysis provides nuanced insights beyond BMI, highlighting the roles of central fat distribution and fluid balance in OSA pathophysiology. These findings underscore the clinical utility of incorporating detailed body composition assessment into the routine evaluation of patients at risk for OSA