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Measurement of heavy metals/metalloids levels with using dytiscidae (coleoptera) species, collected from six different cities of Turkey
(Iğdır Üniversitesi, 2020) Aydoğan, Zeynep; İncekara, Ümit; Gürol, Ali; Darılmaz, Mustafa Cemal
This study was performed to determine the amount of some elements concentration in bodies of the aquatic insects. The contaminants, in six different polluted and non-polluted cities of Turkey, were determined with using predaceous diving beetles. Energy Dispersive X-Ray Fluorescence (EDXRF) spectroscopy was used for determining the concentrations of heavy metals/metalloids in the total body of the insects. Sixteen elements (Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, and Pb) were measured quantitatively in all the samples. Two elements (In, Sn) were measured below the detection limits of EDXRF. Significant heavy metals/metalloids accumulation was seen in two cities and species. Comparison of the studied bio-monitors, Cybister lateralimarginalis showed significantly higher elements accumulation than the other species, so it may be considered as a more suitable species for assessment of heavy metals/metalloids pollution.
Taxonomic status of water vole, (Arvicola Amphibius Linneaus, 1758) in western anatolia
(Hitit Üniversitesi, 2019) Gözcelioğlu, Bülent; Helvacı, Zeycan; Çolak, Ercüment
A total of 116 specimens of the genus Arvicola were collected from western part of Turkey(Western part of Anatolia and Turkish Thrace) and examined based on geometricmorphometrics and traditional morphometrics. Morphometrical analyses showed that A.amphibius populations in western part of Turkey are highly differentiated as Anatolian andThrace populations. Depend on morphometrical differentiation, we conclude that thesetwo populations, classified within two subspecies; Arvicola amphibius persicus and Arvicolaamphibius cerncavskii respectively.
Decolorization of Reactive Blue 19 Dye by Bacillus megaterium Isolated from Soil
(Hacettepe Üniversitesi, Fen Fakültesi, 2019) Erdem, Özgecan; Erkan Türkmen, Kübra; Erdönmez, Demet; Aracagök, Yusuf Doruk; Cihangir, Nilüfer
The principle aim of this study was to decolorize Reactive Blue 19 dye with Bacillus megaterium (B. megaterium) and to determine the effect of some parameters such as pH, temperature, initial dye concentration, nitrogen and carbon sourceson decolorization. With this purpose, a new isolate identified as B. megaterium by genotypic (16S rRNA sequence) characterization, was found effective on Reactive Blue 19 decolorization. Glucose (20g/L) was found as the most suitable carbonsource for Reactive Blue 19 decolorization with a yield of 92%. When the effect of nitrogen sources on decolorization wasinvestigated, the highest dye removal rate was found as 91% which was obtained in shake flask containing yeast extract (10g/L). In trials determining pH effect on dye removal; it was found that B. megaterium enables decolorization of Reactive Blue19 at neutral pHs with a high percentage of 91%. P values were calculated for all parameters and found as p<0.05. Results ofFTIR analysis showed that decolorization of Reactive Blue 19 by B. megaterium occurred via biodegradation. When chemicaland physical wastewater treatment methods were compared to the biological methods, usage of microbial sources such asB. megaterium is considered as an efficient and economical alternative.
Antifouling bakır pritiyonun midye (Mytilus galloprovincialis)’de toplam hemosit sayıları üzerine etkilerinin belirlenmesi
(Ege Üniversitesi, 2018) Günal, A. Çağlan; Gül, Göktuğ; Katalay, Selma; Erkmen, Belda; Ayhan, Melike Merve; Ünlü Erkoç, Figen
Bu çalışmada, 24 ve 96 saat süre ile 10 ve 30 µg/L subletal bakır pritiyona (CuPT) maruz kalan denizel kirliliğin indikatör canlılarından kara midyelerin (Mytilus galloprovincialis) total hemosit sayıları üzerindeki etkisi incelenmiştir. Toplam hemosit sayısı (THS) sağlık göstergesi ve stres indikatörü olarak kullanılan bir parametredir. Yapılan mikroskobik sayımlar sonunda Bakır pritiyona maruz kalan midyelerde toplam hemosit sayıları kontrol grubuna göre azaldığı belirlenmiştir.
Antioxidative, Antiproliferative and Antiangiogenic Activities of Nigella sativa L. pulp, a Waste Material Remaining from Oil Production
(Hacettepe Üniversitesi, Fen Fakültesi, 2018) Tan, Gamze
The aim of this study was to investigate the biological activities such as antioxidative, antimetastatic and antiangiogenic properties of the Nigella sativa L. (NS) pulp, which is a waste material of the oil production process. Following the investigation of the characteristic properties of NS pulp extract with UV-visible (UVvis), fourier-transform infrared (FTIR) and gas chromatography-mass spectroscopy (GC-MS) measurements, its antioxidative capacity was determined using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and Trolox equivalent antioxidant capacity (TEAC) assays. Antiproliferative effects of the pulp extract were tested on both cancerous and non-cancerous cells to examine whether the effects are specific to cell types. Antiangiogenic tests were performed via chick chorioallantoic membrane (CAM) assay. The results showed that the NS pulp extract still maintained its radical scavenging effects and reduced the proliferation of cancer cells more efficiently compared to non-cancerous cells. Furthermore, CAM assays demonstrated that the pulp extract effectively limited vascular endothelial growth factor (VEGF)-stimulated vascularization and development. NS pulp might be used for the suppression of the metastatic cell populations and for the treatment of the diseases particularly like cancer, which progress with pathological angiogenesis. This study highlights that such waste materials from plants can be recycled with various uses in many fields.
Screenıng for anti-quorum sensing and anti-biofilm activity in viscum album l. extracts and its biochemical composition
(Erkan Mor, 2018) Erdönmez, Demet; Kenar, Nihal; Erkan Türkmen, Kübra
Many opportunistic pathogenic bacteria use the Quorum Sensing (QS) system to coordinate their virulenceexpressions. Thus, QS can likely be a new approach to control bacterial infections. The aim of this study was to evaluate theantimicrobial, anti-biofilm, and anti-quorum sensing activities of ethanol, chloroform, and dichloromethane: methanol extractsof leaf, stem, and fruits of the European mistletoe Viscum album L. on 2 Gram-positive and 7 Gram-negative pathogenicbacteria. The extracts at concentrations ranging from 50 to 250mg/ml were tested depending on the extracts of the plant partsand the test bacteria. The extract with 50mg/ml concentration, in which no antimicrobial activity was observed, was used foranti-quorum sensing and antibiofilm studies. The dichloromethane: methanol extracts were found to show the highest biologicalactivities. QS activities of the plant extracts were also determined using the recently established Chromobacterium violaceumCV026 reporter strain and the signaling molecule N-(ß-ketocaproyl)-L-homoserine lactone (3-oxo-C6-HSL) agar welldiffusion assay. Biofilm was quantified using the microtiter plate test and the crystal violet assay. Anti-microbial, anti-biofilm,and anti-quorum sensing activity of leaf and stem extracts showed higher efficiency than fruit extracts. It was concluded thatthe extracts of V. album had the potential to treat microbial infections by biofilm inhibition or inhibition of QS.
Mitigation effect of grape seed extract against cadmium-induced hormonal toxicity in common carp (Cyprinus carpio)
(Springer Nature, 2025) Korkmaz, Nuh; Erdoğan, Kenan; Örün, Gül Nihal; Erkmen, Belda; Doğru, Mehmet ilker; Doğru, Arzu; Polat, Hüseyin; Örün, İbrahim
Background Cadmium (Cd), a highly toxic heavy metal, poses a significant threat to aquatic organisms by disrupting endocrine and metabolic processes. Its bioaccumulation in fish can impair hormonal regulation, leading to growth suppression, stress, and thyroid dysfunction. Alternative strategies using natural compounds are being explored to mitigate these toxic effects in aquaculture. Objective In this study, the protective potential of grape (Vitis vinifera L.) seed extract (GSE) against the toxic effects of cadmium (Cd) on growth hormone, stress hormones, and thyroid hormones in common carp (Cyprinus carpio L.) was investigated for the first time. Methods A total of 420 common carp (average weight: 75±5.0 g; average length: 15±2.0 cm) were used, and the experiments were conducted over acute (4 days) and subchronic (30 days) periods. The fish were randomly divided into seven groups, including a control group, a vehicle group (ethanol), a cadmium-only group (20 ppb), two groups receiving GSE alone (5 mg/kg and 10 mg/kg), and two groups receiving cadmium combined with GSE (5 mg/kg and 10 mg/kg). The GSE dosages were calculated based on the body weight of each fish (mg of extract per kg of fish body weight) and administered daily via gavage. Results Cadmium exposure caused significant hormonal disruptions in common carp, including reductions in growth hormone, insulin-like growth factor 1, thyroid-stimulating hormone, and triiodothyronine levels, along with elevations in cortisol and thyroxine levels during both acute and subchronic exposure periods (P<0.05). Grape seed extract treatment mitigated many of these effects, particularly in the acute phase. It improved growth hormone and insulin-like growth factor 1 levels, reduced elevated cortisol concentrations, and notably increased free triiodothyronine levels, thereby contributing to the partial restoration of thyroid hormone balance. However, in the subchronic period, some hormonal disruptions-especially reduced growth hormone levels-persisted despite GSE administration. Conclusions These findings suggest that GSE may serve as a natural protective agent against heavy metal toxicity (Cd) and offer an alternative solution in aquaculture.
Carbon Nano-Onions in Biological Applications: Recent Progress and Future Directions
(Aksaray Üniversitesi, 2025) Soylukan, Caner; Karaduman, Tuğçe Karaduman; Akyüz, Lalehan
Carbon nano-onions (CNOs), together with graphene and its derivatives, are one of the most interesting carbon nanostructures due to their peculiar chemical and physical properties. Made of a number of concentric fullerene layers, carbon-based structures have a peculiar design and assume the appearance of onion-like cages. Due to their excellent biocompatibility and safety, CNOs have low toxicity, high water dispersibility (due to surface functionalization), and high pharmacological efficacy. These properties render them highly appealing for applications such as drug delivery, sensing, imaging, tissue engineering, and therapeutic agents. While CNOs were discovered almost at the same time as other carbon nanomaterials (CNMs), their potential in biological applications remains largely unexplored. On the other hand, similar to other CNMs and fullerenes, CNOs play a crucial role as they represent carbon's ability to form diverse nanostructures with exceptional properties. This review aims to summarize recent studies on CNOs for biological applications, underlining the current achievements, possible opportunities, and challenges toward future development.
Testing and optimizing methodologies for microplastic extraction from owl pellets
(TUBITAK, 2025) Seyfe, Merve; Seyfe, Melike; Kankılıç, Tolga; Tavşanoğlu, Ülkü Nihan
Microplastic pollution is a pressing global environmental concern, potentially threatening ecosystems and entering the food chain. Owls, as nocturnal carnivorous birds, are at significant risk of ingesting microplastics due to their diverse foraging habits. This study aimed to identify the most suitable procedure for extracting microplastics from owl pellets, focusing on efficiency, functionality, and cost and ensuring the extraction of both prey and microplastics without damage. Experiments were conducted on pellets from long-eared owl (Asio otus) collected from three different habitats in Ankara, Türkiye. The extraction of microplastics was then tested using various treatments (n = 25), involving different durations, temperatures, and chemicals. A total of 100 pellet samples were utilized with three replicates for each treatment. The study identified three different methods particularly effective for microplastic extraction: using 10% sodium hydroxide (NaOH) solution at 55 °C for 75 min, using 10% potassium hydroxide (KOH) at 55 °C for 75 min, or using Fenton reagent (30% H2 O2 + FeSO4) at 50 °C. Additionally, immersing the pellets in a 60 °C water bath for 10 min improved the sorting of prey items. Overall, the most effective approach for extracting microplastics considering the balance of time, cost, and effort was using 10% KOH solution at 55 °C for 75 min.
Dead Cell Discrimination with Red Emissive Carbon Quantum Dots from the Medicinal and Edible Herb Echinophora tenuifolia
(Springer, 2025) Özdemir, Naciye; Tan, Gamze; Tevlek, Atakan; Arslan, Gülşin; Zengin, Gökhan; Sargın, Idris
Accurately determining the viability of cells is crucial for in vitro cell research. Fluorescence-based live/dead cell staining is a highly desirable method to assess cell viability and survival in in vitro studies. We describe a green synthesis method to create red-emissive CQDs from the medicinal and edible herb Echinophora tenuifolia using microwave irradiation. We observed that the biocompatibility and photostability of the CQDs are superior. The antioxidant capacity of the CQDs and the plant extract were also investigated using different chemical methods (DPPH, ABTS, CUPRAC, FRAP, PBD, and MCA). The antioxidant capacity of the CQDs was similar to that of the extract of E. tenuifolia. Cytotoxicity studies indicate that while the CQDs are not toxic to L929, they exhibit significant toxicity towards HepG2 cells. The CQDs exhibited a strong negative zeta potential (-44.0 mV), which contributed to their selective interaction with dead cells while being repelled by viable cells with intact membrane potentials. The optimal concentration for effective, non-toxic imaging was determined to be 25 µg/mL, as lower concentrations did not produce detectable fluorescence. Differential staining experiments confirmed that CQDs selectively stained dead cells, with red fluorescence observed under the Texas Red filter. Moreover, CQDs exhibited favorable fluorescence intensity and stability, which may offer advantages for long-term and reliable bioimaging applications. In vitro studies on HepG2 and L929 cell lines revealed that the red-emissive CQDs from E. tenuifolia can be potentially used in bioimaging.
siRNA-guided dual-targeting nanocarrier for breast cancer treatment
(Taylor and Francis Ltd., 2025) Karahaliloğlu, Zeynep; Şahin, Betul; Karahaliloğlu, Zeynep; Çelik, Ekin; Hazer, Baki
This study aimed to develop a thermoplastic polyurethane-oleic acid-based nanosystem (TPU-Ole NPs) incorporating siRNA and curcumin (CUR) to overcome multidrug resistance in breast cancer by silencing the c-myc gene. Methods: TPU-Ole and CUR-loaded NPs were prepared via solvent evaporation and coated with poly-L-lysine (PLL) for siRNA attachment. NPs were characterised by dynamic light scattering (DLS) for mean diameter, polydispersity index (PDI), and zeta potential (ZP). Encapsulation (EE) and loading efficiencies (LE) were measured by NanoDrop. Release (pH 5.0; 7.4) and storage stability (pH 7.4) were evaluated using the eppendorf method. siRNA binding was confirmed by agarose gel electrophoresis. Gene silencing and apoptosis were assessed by RT-PCR and flow cytometry. Results: Mean diameter, PDI, and ZP of NPs were 170 ± 2 nm, 0.011 ± 0.080, and −27.5 ± 0.11 mV. EE and LE were 75 ± 0.12 and 14.2 ± 0.06%. Sustained release and good stability were observed. Conclusion: siRNA-CUR-NPs efficiently silenced c-myc and induced apoptosis in MCF-7 cells.
First report on phytochemical content and biological activities of seseli salsugineum A. Duran & lyskov: a new endemic species
(Taylor and Francis Ltd., 2025) Önder, Alev; Doğan Güner, Ebru; Sarıtaş, Mehmet; Trendafilova, Antoaneta; Tekşen, Mehtap; Zengin, Gökhan
Five pyranocoumarins (1-5) together with a simple coumarin, umbelliferone (6), have been isolated from Seseli salsugineum A. Duran & Lyskov, a newly described endemic species for Türkiye, and their structural elucidation was performed by spectroscopic analysis and comparison with the literature data. In addition, hexane, dichloromethane (DCM), and methanol (MeOH) extracts were examined for their antioxidant and enzyme inhibition potentials. The current study is the first report on an endemic S. salsugineum, regarding interesting bioactive coumarins (pyranocoumarins and a simple coumarin) and the extract’s biological properties. Further research is needed to isolate new compounds from this plant and uncover its potential uses as a health-promoting and healing agent.
The Catalytic Activity of Carob Extract-Capped Silver Nanoparticles in the Remediation of Recalcitrant Nitroaromatics
(Springer, 2025) Tan, Gamze; Sargın, İdris
Nitroaromatic compounds are highly stable pollutants in the aquatic environment, posing serious health risks due to their mutagenic, carcinogenic, and toxic nature. In this study, the catalytic reduction of four organic pollutants (o-aminonitrobenzene, p-nitrophenol, 2,4-dinitrophenol, and 1,2-diamino-4-nitrobenzene) to corresponding aminobenzenes was achieved using sodium borohydride (NaBH4, the reducing agent) and carob extract-capped silver nanoparticles (cc-AgNPs; the catalyst) under ambient conditions. The silver catalyst, cc-AgNPs, was biosynthesized, adopting an eco-friendly green synthesis approach in which carob (Ceratonia silique L.) pod water extract was used as a reducing and capping agent. The cc-AgNPs were characterized using various techniques, including Ultraviolet-visible (UV-vis) spectroscopy, Fourier Transform Infrared spectrometer (FT-IR), Transmission Electron Microscopy (TEM), zeta size and potential measurements. The UV-vis spectra of cc-AgNPs showed a characteristic surface plasmon resonance peak at 422–425 nm. Analysis of the FT-IR spectrum confirmed that the cc-AgNPs were coated with carob extract. Zeta potential measurement indicated that the surface charge of the catalyst was negative (-21.4 ± 0.7 mV). Based on TEM results, the average size of the cc-AgNPs was 33–43 nm. cc-AgNPs reduced the nitroaromatics to aminobenzene derivatives in < 1 min. in the presence of the reductant NaBH4. The study revealed that cc-AgNPs are effective in catalytic hydrogenation of nitroaromatics. The cc-AgNPs can be used in environmental remediation to eliminate persistent nitroaromatics and convert them into valuable amino benzene precursors. These precursors can then potentially be used to produce various organic compounds for applications in the pharmaceutical, organic synthesis, and dye production industries.
Two new moss records for Turkey and Southwest Asia
(Taylor and Francis Ltd., 2025) Ezer, Tülay; Aslan Ergenekon, Züleyha; Uygur, Ahmet; Keskin, Ali; Alataş, Mevlüt; Batan, Nevzat
Hymenoloma mulahaceni and Mnium blyttii found as new to Turkey following a recent bryological excursion to the Bolkar Mountains (Taurus Mountain range) in Turkey. Also, this is the first record of the Mnium blyttii from Southwest Asia. Illustrations, geographic distributions, ecological characteristics, identification keys and comparisons with morphologically similar taxa are given.
Characterizing the Helminth Community of the Mountain Gazelle (Gazella gazella Pallas, 1766) Through DNA Metabarcoding
(Springer Science and Business Media Deutschland GmbH, 2025) Karaer, Mina Cansu; Karataş, Büşra; Madak, Elif; Sönmez, Hande İrem; Keskin, Emre; Sarımehmetoğlu, Hıfsı Oğuz; Kankılıç, Tolga; Tavşanoğlu, Çağatay
Understanding parasite diversity in wild and captive animal populations is vital for their individual health and ecosystem dynamics. The helminth community in mountain gazelles (Gazella gazella Pallas, 1766), particularly in the isolated northernmost population in Türkiye, remains poorly understood, posing challenges for conservation. This study aimed to identify and compare the diversity of helminths in captive and free-ranging mountain gazelles in Hatay, Türkiye, while assessing potential zoonotic risks. Methods: We collected a total of 188 fresh fecal samples from both captive and free-ranging populations. The samples were analyzed using DNA metabarcoding to assess helminth species and their species diversity across seasons. Results: Our findings revealed eight helminth taxa in Gazella gazella, including six intestinal and two lung nematodes, with four of these species previously unreported in Türkiye. We also found seasonal differences in helminth composition and abundance. Conclusions: The identification of these helminth taxa highlights the value of advanced molecular techniques in uncovering parasite diversity in ungulates. Seasonal differences in helminth composition and abundance, and the biological characteristics of the detected helminth species align with the climatic parameters of the seasons in which they were identified.
Active surface modification of thermoplastic polyurethane-oleic acid nanocomposite fibers through alkali hydrolysis
(John Wiley and Sons Inc, 2025) Karahaliloğlu, Zeynep; Hazer, Baki
Alkali hydrolysis is a simple, low-cost, and prominent surface modification method for developing more desirable scaffolds. In the presented study, two distinct concentrations (1 and 3 M) were predetermined for the hydrolysis treatments, and thermoplastic polyurethane (TPU) nanocomposite fibers with varying concentrations of oleic acid (OLE) were exposed. According to the scanning electron microscopy (SEM) images, when naked TPU or nanocomposite fibers showed any morphological changes, the interfacial bonding points of TPU-OLE nanocomposite fibers enhanced in the higher concentrations of hydrolysis solution (1 and 3 M). The average fiber diameter in pure TPU is 0.59 ± 0.04 μm, while after doping with the highest concentration of OLE, the fiber diameter decreased to 0.48 ± 0.03 μm. Additionally, at the highest NaOH and OLE concentrations, the diameter decreased from 0.85 ± 0.02 μm in 3 M/TPU to 0.61 ± 0.04 μm in 3 M/TPU-OLE3. Additionally, the surface hydrophilicity of TPU-OLE fibers was noticeably improved through alkali hydrolysis, compared to the naked TPU approximately by 70%. Furthermore, the surface characterization of fibers revealed that the surface roughness values showed a significant change with increasing alkali concentration, but were not affected by the OLE concentration. All these findings indicate that TPU, whose surface wettability, roughness, and antibacterial response are modified by mercerization and OLE addition, can be safely and successfully used in tissue engineering applications. Highlights: Polyurethane, oleic acid, and NaOH treatment were combined for tissue engineering applications. TPU/OLE nanofiber membranes were prepared by electrospinning. The surface of composite fibrillar membranes was modified alkali hydrolysis. The fiber diameter decreased after NaOH hydrolysis. Alkali hydrolysis improved the surface wettability and antibacterial response.
Fritillaria behcetiana (Liliaceae), a new species from eastern Anatolia (Türkiye)
(Magnolia Press, 2025) Yapar, Yakup; Tekşen, Mehtap
Fritillaria behcetiana sp. nov. is described as a new species from Bingöl Province in eastern Anatolia, Türkiye. It is closely related to F. shehbazii, F. chlororhabdota and F. pinardii, but differs from them in several morphological features, including leaf lenght and colour, perianth segment size and colour, anther colour and length, filament length, style lenght and branching. The new species is described in detail, including distribution, ecology, conservation status and photographs with comparisons to F. shehbazii, F. chlororhabdota and F. pinardii.
Exploring the anti-inflammatory and cytotoxic effects of Valeriana tuberosa L. constituents: Integrating in vitro and in silico studies
(Elsevier B.V., 2025) Çelik, Cansel; Özhan, Yağmur; Öztürk, Ceren; Dede, Zülal Sevgi; Çitoğlu, Tuğçe; Tekşen, Mehtap
Valeriana tuberosa L. yielded four new iridoids, valtuberoside I-IV (1–3 and 15), along with 13 known secondary metabolites via activity-directed fractionation. Compounds were characterized by NMR and HRESIMS. EtOH extract, fractions, and isolates were evaluated for their inhibition on nitric oxide (NO) release in LPS-induced RAW 264.7 cells. Compounds 3, 4, 6, 8, 9, 11, 13, 16, and 17 exhibited anti-inflammatory activity by inhibiting the release of NO (IC50 43.44–95.71 μM), and their mode of actions were elucidated by ELISA, Western blot, qPCR, immunostaining techniques and supported by molecular modelling studies. Compounds 8, 9, 11, 13, and 17 showed significant reduction in TNF-α, IL-1β, IL-6, PGE2, and COX-2 enzyme production, while 9 and 13 decreased iNOS protein expression in RAW 264.7 cells. Compound 13 exhibited remarkable inhibition on pro-inflammatory markers, cox-2 gene expression and translocation of NF-κB to the nuclear region. Moreover, it had the most favourable interaction (ds: −6.46 kcal/mol) with iNOS in in silico analyses. The cytotoxic activities of the most active isolates against MCF-7, MDA-MB-231, U87, A172, MIA PaCa-2, PANC-1, Mahlavu, and Hep3B cancer cell lines were assessed using CCK8 assay and their cell death mechanisms were unveiled via Apoptosis/Necrosis Assay Kit. Compound 8 had significant cytotoxic activity against MIA PaCa-2 (IC50 23.7 μM) and Hep3B (IC50 25.4 μM) cancer cell lines, via arresting cell cycle especially in G2/M phase and triggering the apoptotic pathway. These findings indicated that 8 and 13 deserve further in vivo assays on the way to discover new potential drug leads.
Thermoplastic Polyurethane-Oleic Acid (TPU-OLE) Membranes for Guided Bone Regeneration
(John Wiley and Sons Inc, 2025) Karahaliloğlu, Zeynep; Hazer, Baki
Guided bone regeneration (GBR) is a regenerative surgical procedure in dentistry and orthopedics. The aim of this study is to fabricate a novel nano-textured, hydrophilic thermoplastic polyurethane (TPU)-based barrier membrane containing unsaturated fatty acid, oleic acid (OLE) to assist GBR. First, TPU copolymer containing OLE in different ratios was synthesized, and GBR membranes were fabricated by the solvent casting method, and then, the surface properties were improved by alkali treatment. Thus, a TPU-OLE structure was obtained with improved surface wettability, the ability to prevent bacterial adhesion, and the capability to promote cell adhesion. The contact angle reduced from 73.3° ± 1° to 30.7° ± 0.3° at TPU-OLE3, while at TPU it decreased from 121.2° ± 2.5° to 63.6° ± 0.8° after treatment with 3 M sodium hydroxide (NaOH) solution. Furthermore, plate counting assays showed that TPU-OLE membranes displayed excellent bacterial inhibition (against Escherichia coli and Staphylococcus aureus); the control group showed 6 × 107 CFU/mL of E. coli bacterial colonies, while on the plates interacting with TPU-OLE1, TPU-OLE2, and TPU-OLE3 membranes, colonies of 12 × 105, 12 × 105, and 24 × 105 CFU/mL were observed, respectively. The bacterial count on TPU-OLE1, TPU-OLE2, and TPU-OLE3 membranes decreased by 109, 164, and 12 × 105 CFU/mL at 24 h, while the control group and TPU membranes showed 1300 × 105 and 600 × 105 CFU/mL, respectively. The obtained results indicated that either alkali treatment or OLE-modified TPU produced a more hydrophilic and promotive surface for cell attachment. Therefore, we anticipate that alkali-treated TPU-OLE membranes have a great potential in GBR in future applications.
Cryopreservation of ram semen: baicalein efficiency on oxidative stress, chromatin integrity, viability and motility post thaw
(Frontiers Media SA, 2024) Avdatek, Fatih; Güngör, Şükrü; Gülhan, Mehmet Fuat; İnanç, Muhammed Enes; Olğaç, Kemal Tuna; Denk, Barış; Yeni, Deniz; Taşdemir, Umut
Baicalein (B) has potential antioxidant properties, but it has not been tested as a ram semen extender. This study aimed to assess the impact of B on various sperm parameters and determine its potential influence on semen quality after the freeze-thawing process. During the breeding season, ejaculates were obtained from four rams with the aid of an artificial vagina. The collected mixed semen samples were divided into four groups: control (C; 0), B0.5 (0.5 mM), B1 (1 mM), and B2 (2 mM). After semen extension, the samples were loaded into 0.25 mL straws and stored for 2 h at 4°C prior to freezing in liquid nitrogen vapor and thawed in a water bath at 37°C. Among the groups, B0.5 demonstrated the highest progressive motility results, while B1 and B2 exhibited reduced motility (p < 0.05). In terms of high mitochondrial membrane potential, plasma membrane and acrosome integrity, and viability, B0.5 showed significantly superior outcomes to the other B groups (p < 0.05), although it was not significantly better than C. B1 displayed the highest plasma membrane integrity levels (p < 0.05). Notably, B2 displayed the lowest total antioxidant status levels among the groups (p < 0.05). The findings of this study suggested that the in vitro spermatological characteristics of ram spermatozoa such as progressive motility and chromatin integrity can be protected from the freeze-thawing process by using the 0.5 mM dose of baicalein as a semen extender. The treatment of sperm freezing might benefit from further in-depth research on the role of B in the improvement of cryoinjury and its underlying processes.

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