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C/EBPα Mediated Transcriptional Regulation of Human ADAMTS-3 Gene and Collagen Expression in Osteosarcoma Cells

ADAMTS-3 is a procollagen amino proteinase mainly expressed in type II collagen-rich tissues and its primary function is to maturate amino ends of the type II collagen precursors. This maturation process allows correct fibril formation. ADAMTS-3 also has a tumor-suppressive function by regulating the fibronectin expression in the ECM. C/EBPα is a transcription factor playing a pivotal role in the cell cycle regulation. Dysregulations in the C/EBPα expression have been reported in solid tumors. C/EBPα expression has been identified to be associated with the metabolism and prognosis of a malignant bone tumor, osteosarcoma (OS). High heterogeneity, metastasis capability, and recurrence lead to poor prognosis and survival rates in OS. Multiple genetic and epigenetic factors affect OS development. Alterations in the ECM elements are closely related to OS development and progression. According to the in-silico analyses, the ADAMTS-3 promoter includes multiple C/EBPα binding sites suggesting that C/EBPα could have a regulatory effect on ADAMTS-3 transcriptional regulation. In the present study, over-expression of the C/EBPα decreased ADAMTS-3 mRNA and protein levels in Saos-2 and MG-63 osteosarcoma models. Ectopic expression of the C/EBPα also led to alterations in some fibrillar collagen expression levels. Enhanced C/EBPα levels resulted in an increase in the type I and II collagen expression levels but didn’t change the type III collagen expression level in Saos-2 cells.

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Structural, Magnetic and Catalytic Properties of FeCo Nanoparticles Synthesized by Polyol Process

Multi-functional FeCo nanoparticles (NPs) exhibit unique structural, magnetic and catalytic properties, making them versatile materials with potential applications in diverse fields. In this work, we investigated the structural, electrochemical and magnetic properties of as-prepared FeCo NPs synthesis by polyol method. X-ray diffraction analysis revealed multiphase structures: FeCo and α-Fe2O3 phases and scanning electron microscopy images confirmed spherical-like structures of FeCo NPs with an average size of 12.4 ± 0.1 nm. The electrochemical properties of FeCo NPs were investigated using a three-electrode setup in a 1 M KOH electrolyte at room temperature. The onset potentials for FeCo catalysts were found to be -0.15 V for ORR, 0.25 V for OER, and -1.26 V for HER. Tafel measurements further elucidated the reaction mechanism, revealing corrosion potentials of -0.165 V for ORR and 0.215 V for OER, with Tafel slopes of 228 mV dec-1 and 48 mV dec-1, respectively. A significant increase in magnetization was observed below 25 K in both zero-field-cooled and field-cooled curves, with a magnetic transition occurring at Ts=15 K, possibly indicating a ferromagnetic-to-antiferromagnetic phase transition. The hysteresis loop measurements revealed coercive field values ranging from 968 Oe at 5 K to approximately 206 Oe at 320 K, indicating a relaxation in magnetic spin orientation with increasing temperature. The saturation magnetization (Ms) values were recorded as 15.2 emu/g under a 5 T magnetic field, and the remanent magnetization (Mr) showed dominant ferromagnetic properties at 5 K with an Mr/Ms ratio indicating soft magnetic behavior. The magnetic susceptibility of FeCo NP exhibited a peak at approximately 25 K, and the Curie-Weiss law provided an estimated θ angle of -9.58°, suggesting antiferromagnetic interactions.

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The Effect of Sintering Temperature on Magnetic Cooling Parameters in La2MnNiO6 Double Perovskite Manganite Material

La2NiMnO6 çift-katlı perovskit manganit sistemi sol-jel yöntemi ile üretilmiş, LNM-1000 örneği 1000 ˚C'de, LNM-1100 örneği ise 1100 ˚C'de sinterlenmiştir. Üretilen örneklerin yapısal, morfolojik, manyetik ve manyetokalorik özellikleri incelenmiştir. Numunelerin kristal yapısının Rombohedral yapıda ve R3 ̅c uzay grubunda olduğu belirlendi. Morfolojik özellikleri incelendiğinde LNM-1000 numunesinin küçük yapılı, çok köşeli ve düzensiz şekilli taneler içerdiği, LNM-1100 numunesi içinse bu bilgilerin yanında bazı yerlerde tane sınırlarının belirsizleştiği görülmektedir. LNM-1000 ve LNM-1100 numuneleri için Curie sıcaklıkları 200 ve 220 K olarak belirlenirken efektif manyetik moment değerleri sırasıyla 1.75 ve 2.13 B olarak hesaplanmıştır. Arrot grafikleri, numunelerin ikinci dereceden manyetik faz geçişi sergilediğini göstermektedir. Maksimum manyetik entropi değişimi ve bağıl soğutma gücü değerleri LNM-1000 ve LNM-1100 numuneleri için sırasıyla 0,21, 0,25 J kg-1 K-1 ve 46,2, 50,5 J kg-1 olarak hesaplanmıştır. Örnekler Gd2NiMnO6 örneğinden (5 K) çok daha yüksek olan oda altı sıcaklık aralığında Curie sıcaklığına ve ikinci dereceden manyetik faz geçişine sahip olmalarına rağmen, nispeten düşük manyetik entropi değişim değerleri, manyetik soğutucu malzeme olarak kullanımlarını sınırlandırmaktadır.

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