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    Alterations in the immunoreactivity of laminin, type IV collagen and ?3?1 integrin in diabetic rat ovarian follicles
    (Comenius Univ, 2020) Yildirim, A. B.; Karabulut, D.; Ozturk, E.; Kaymak, E.; Yalcin, B.; Kuloglu, N.; Akkus, E.
    AIM: In order to determine the possible effects of diabetes, we aimed to investigate the expression of extracellular matrix proteins in the theca and granulosa layers in different follicular stages. METHODS: Thirty-two adult Wistar albino male rats were divided into 4 groups as control and sampled groups. Four, eight and twelve weeks after inducing diabetes with an intraperitoneal injection of streptozotocin (40 mg/kg), the expressions of laminin, type IV collagen and alpha 3 beta 1 integrin in ovarian tissues were evaluated by immunohistochemical method. RESULTS: In our study, in the first month of diabetes, a significant increase was observed in laminin, type IV collagen and alpha 3 beta 1 integrin expressions in all follicle types compared to the control group in both the theca and granulosa layers. Laminin and type IV collagen immunoreactivity tended to increase in D2 and D3 groups also. Integrin expression did not change in the newly formed follicles in the D2 and D3 groups, however, it tended to change and increase in the developing follicles. CONCLUSIONS: The changes in the expression of laminin, type IV collagen and alpha 3 beta 1 integrin, which are the extracellular matrix proteins in the follicle, along with diabetes, show that diabetes plays a role in the regulation of follicular development (Tab. 4, Fig. 36, Ref. 29).
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    Structural and temperature-dependent photoluminescence properties of NaBaBO3:Ce3+,Tb3+phosphors synthesized using the combustion
    (Elsevier, 2024) Altowyan, Abeer S.; Oglakci, M.; Topaksu, M.; Ozturk, E.; Hakami, Jabir; Coban, M. B.; Keskin, M. Ozgur
    This study explores the structural and temperature-dependent photoluminescence of Ce3+ and Tb3+ doped NaBaBO3 phosphors, synthesized via combustion. Analysis of their crystal structures confirmed excellent alignment with the standard PDF#98-008-0110. Investigation into both room and lowtemperature photoluminescence revealed that the dopants have a significant effect on emission spectra. Ce3+-doped samples exhibited excitation peaks at 275 nm and 358 nm, leading to a primary emission at 419 nm, with enhanced low-temperature emission suggesting reduced non-radiative processes. Tb3+doped phosphors showed excitation from 250 to 377 nm and emissions from blue to deep red, including strong green emission at 550 nm due to 5D4?7F5 transitions. Optimal doping was found at 1 mol% for Ce3+, while Tb3+ showed increased luminescence up to 3 mol%, with concentration quenching observed beyond these points. The study indicates dipole-dipole interactions dominate Ce3+ concentration quenching, whereas Tb3+ involves both electric dipole and quadrupole interactions. This analysis provides insights into enhancing luminescent efficiency and suggests NaBaBO3:xCe3+,Tb3+ phosphors' potential in advancing white LED technology, highlighting their stable luminescent properties at low temperatures. (c) 2024 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights are reserved, including those for text and data mining, AI training, and similar technologies.