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101.
Thirteen river basins draining into the Marmara, Aegean and Mediterranean Seas were selected for evaluation of European eel (Anguilla Anguilla L., 1758) catch in Turkey. These basins were grouped into three so-called “eel monitoring area” (EMA). The official province-based annual landing data between 1996 and 2018 were assessed for each of the monitoring areas. Statistically significant decreases over the years were observed in the landing data in all of the monitoring areas. The adequate protection of the European eel standing stocks, particularly in some critical eel habitats such as Köyceğiz lagoon showed over time a small decrease in eel catches in EMA-2. However, a substantial decrease was detected in the province of Adana, which includes the Seyhan and Ceyhan basins, and these are located in the EMA-3. The catch data mainly based on the commercial fisheries and the restriction on export seems to be the main reason for the decline in catches in the three EMAs. Thus the suggested monitoring areas (EMAs) are needed to structure research programmes on basic knowledge on escapement ratio of migrating silver eels, arrival and upstream migration of glass eels in the rivers of each of the EMAs in order to build area specific management strategies. These monitoring areas may provide practical units that management can use in future fisheries regulations. 相似文献
102.
Molecular Biology Reports - Meteorin-like hormone (Metrnl) is a peptide secreted from the adipose tissue and modulates the whole-body energy metabolism. Metrnl release into the circulation is... 相似文献
103.
Amino Acids - Naturally occurring frog skin peptides are one of largest sources of antimicrobial peptides that have many advantages including high potency, broad spectrum of targets and low... 相似文献
104.
Özgür Yiğiter MD Ali Cagdas Yorukoglu MD Nilay Şentürk MD Yavuz Dodurga MD Ahmet Fahir Demirkan MD 《Journal of cellular biochemistry》2019,120(7):11525-11530
The aim of this study is to investigate the effects of type I collagen on bone defects and on genes specifically for osteogenesis in a rat model. Two millimeter drill hole bone defect was created in the femur of rats. In the experimental group, type I collagen was applied in bone defects whereas in control group defects were left empty. Inflammation, development of connective tissue, osteogenesis, and foreign body reaction parameters evaluated with histologically and genes evaluated by blood samples. In the experimental group, the histopathologically significant change was found in favor of bone healing only at the first week. A significant increase was found in genetic expressions of BMP-1, 2, 3, 4, 5, 6, 7, TGF-βRII, Smad-1, IL-6, BMPR-IA, BMPR-IB, Eng, BMPR-II, c-fos, Cdkn1a, Chrd, Gdf-5, Id-1, PDGF-β, IGF-1, Serpine-1, and TGF-βRI at the first hour. At the first, third, and sixth week, no significant increase was found in any of the gene expressions. Type I collagen is found to be effective in favor of bone healing through increased inflammatory cytokines and expression of BMP genes in the early stages of fracture healing. 相似文献
105.
Canan Y. Karakaş Hande Tekarslan Şahin Benan İnan Didem Özçimen Yıldız Ö. Erginer 《Biotechnology progress》2019,35(6):e2876
Reactive oxygen species can bind protein, DNA, lipids, and carbohydrates and thus cause an oxidation reaction that induces various syndromes such as cardiovascular diseases, degenerative disease, and cancer types in the human body. Bioactive compounds, such as PUFA, EPA, DHA, and carotenoids in algae, have a chain ring and protect the tissue from chemical damage and reverse the symptoms of some diseases. Algal bioactives also have various biological properties such as anticoagulants, antiviral, antiangiogenic, antitumor, anti-inflammatory, antioxidant, antiproliferative, and immune modulation properties. This study aimed to show in vitro cytotoxic activity effect of Chlorella protothecoides and Nannochloropsis oculata microalgal extracts loaded nano–microparticles on A-172 (Homo sapiens brain glioblastoma) and HCT-116 (H. sapiens colon colorectal carcinoma) cell lines because of the increasing importance of algal biotechnology. MTT viability tests were performed on HUVEC, A172, and HCT 116 cells with particles obtained at optimum process parameters. The cell viability rates of encapsulated particles were also compared with pure algae extracts. Microalgal extracts loaded nano–micro particles showed very promising results for cytotoxic effect on cancer cells. 相似文献
106.
GAMZE DERELI CAN ÖZGE EKIN AKDERE MEHMET EROL CAN MENEMŞE GÜMÜŞDERELIOĞLU 《Cytotherapy》2019,21(1):83-95
Background
Several methods to cultivate limbal epithelial stem cells (LESCs) in vitro with the support of feeder layers and different growth medium formulations have been established for several years. The initial green medium consists of various ingredients that exhibit a non-optimal level of biosafety, therefore, different modifications have been made to suit it to safe clinical applications. However, the question of which formulation is the most appropriate remains to be answered.Aims
This study evaluated the outgrowth kinetics and stemness of cells cultured from human limbal explants with the aim of preserving LESC characteristics in the human-derived platelet-rich fibrin (HPRF)–conditioned medium with no feeder cell layer or carrier for the first time. The final composition of the cell culture system included only human-derived products without any xenobiotic or chemical substances to minimize the potential risk for human health, which will be useful for clinical purposes.Methods
To test our hypothesis, limbal explants were incubated with either Dulbecco's Modified Eagle's Medium (DMEM)/F12-10% human serum (HS), human-derived amniotic membrane (HAM)-conditioned DMEM/F12-10% HS or HPRF-conditioned DMEM/F12-10% HS to determine whether outgrowth kinetics and stemness of cells show any differences among groups.Results
The results showed that the HPRF-conditioned medium showed higher concentration levels of growth factors, which may be involved in the promotion of LESC expansion while preserving the stem cell characteristics. HPRF-conditioned medium had significantly superior capacity to enhance the cell growth rate, the stem/progenitor cell phenotype and the expressions of putative stem cell markers.Conclusion
This novel xeno-feeder-chemical-free, completely human-derived and biologically safe culture system including HPRF and HS would be of interest to replace conventional cell culture strategies to meet safety requirements mandatory for clinical use in humans. 相似文献107.
Esma Kocaoğlu Hüseyin Çavdar Murat Şentürk Deniz Ekinci 《Journal of enzyme inhibition and medicinal chemistry》2019,34(1):51-54
Glutathione reductase (GR) is a crucial antioxidant enzyme which is responsible for the maintenance of antioxidant GSH molecule. Antimalarial effects of some chemical molecules are attributed to their inhibition of GR, thus inhibitors of this enzyme are expected to be promising candidates for the treatment of malaria. In this work, GR inhibitory properties of N-Methylpyrrole derivatives are reported. It was found that all compounds have better inhibitory activity than the strong GR inhibitor N,N-bis(2-chloroethyl)-N-nitrosourea, especially three molecules, 8?m, 8 n, and 8 q, were determined to be the most powerful among them. Findings of our study indicates that these Schiff base derivatives are strong GR inhibitors which can be used as leads for designation of novel antimalarial candidates. 相似文献
108.
AbstractIn the present work, Sycamore (Platanus occidentalis) tree seed pod fibers (STSPF) and nano-scale zero valent iron particles (nZVI) immobilized in Sycamore tree seed pod fibers (nZVI?STSPF) were produced. This biosorbent has been utilized as a viable effective biosorbent in the removing of methylene blue hydrate (MB), malachite green oxalate(MG), methyl violet 2B(MV) dyes from synthetic wastewater. The biosorbents were characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy. Various parameters such as contact time, solution concentration, pH and amount of biosorbent were investigated in order to evaluate the potential of the nanomaterials immobilized on natural wastes as sorbing biomaterials for the cationic dyes. Study on sorption kinetic and the sorption isotherm was carried out and best fitting models for the rate kinetics and isotherms were suggested. Langmuir isotherm was observed to be compatible with the isotherm models. The STSPF in the raw form showed the best dye sorption capacity of 43.67?mg/g for MG, 25.32?mg/g for MV, and 126.60?mg/g for MB. The magnetic nZVI?STSPF showed the best dye sorption capacity 92.59?mg/g for MG, 92.59?mg/g for MV, and 140.80?mg/g for MB. The iron nanoparticles immobilized biosorbent exhibited a higher removal capacity for all dyes compared to the raw biosorbent. 相似文献
109.
Şerife Saçmacı Yakup Yılmaz Şenol Kartal Murat Kaya Fatih Duman 《Biological trace element research》2014,159(1-3):254-262
In this study, the resting eggs of aquatic creatures living in freshwater (Daphnia, Cladocera, Crustacean) ecosystems were used as a novel biosorbent extractant for synchronous preconcentration of trace Cd(II), Co(II), Cu(II), Mn(II), and Ni(II) previous to measurement by flame atomic absorpiton spectrometry (FAAS). Using column procedures, optimization studies were conducted to realize the effective adsorption of the analyte ions such as the solution pH, amount of the biosorbent, volume of the sample, interfering ions, etc. A high preconcentration factor of 67 and low relative standard deflection of ≤4.1 % (n?=?8) were obtained. The invention constrains based on the 3 s/b criterion were 2.4 for Cd(II), 41.4 for Co(II), 4.2 for Cu(II), 3.0 for Mn(II), and 9.6 μg L?1 for Ni(II). The accuracy of the method was verified by analysis of a certified standard reference material. The used procedure was applied to the definition of the analytes in diverse environmental samples with convincing results. Consequently, the resting eggs of Daphnia can be used as a biosorbent for preconcentration and biosorption studies. 相似文献
110.
S. Çevik A. Yıldızlı G. Yandım H. Göksu M.S. Gultekin A. Güzel Değer A. Çelik N. Şimşek Kuş S. Ünyayar 《Journal of plant physiology》2014
Cyclitols were prepared from corresponding allylic hydroperoxides, synthesized by photooxygenation of the appropriate cyclic alkenes. These hydroperoxides were then separately treated with a catalytic amount of OsO4. Synthesized dl-cyclopentane-1,2,3-triol 9 (A), dl-cyclohexane-1,2,3-triol 12 (B), and dl-cycloheptane-1,2,3-triol 15 (C) were used in the investigation of plant stress. Antioxidants, lipid peroxidation, and water status of chickpea species exposed to synthetic cyclitols under water deficit were examined. Cyclitol derivatives significantly decreased leaf water potential, lipid peroxidation and H2O2 levels of wild and cultivated species under water deficit. Cyclitol treatments affected antioxidant enzyme activities differently in both species under water deficit. The highest SOD activity was found in A10-treated Cicer arietinum (cultivar) and C10-treated Cicer reticulatum (wild type) under water deficit. CAT activity increased in C. arietinum exposed to A cyclitols, while it increased slightly and then decreased in cyclitol-treated C. reticulatum under stress conditions. AP and GR activities were significantly increased in C. arietinum under water deficit. AP activity increased in C derivatives-treated C. arietinum, while it remained unchanged in C. reticulatum on day 1 of water deficit. GR activity was increased in A derivaties-treated C. arietinum and C derivatives-treated C. reticulatum on day 1 of water deficit and decreased with severity of stress (except for B10-treated C. arietinum). The level of AsA in C treatments and GSH in A treatments increased in C. arietinum on day 1 of water deficit, while in C. reticulatum, AsA and GSH levels decreased under stress conditions. We conclude that exogenous synthetic cyclitol derivatives are biologically active and noncytotoxic, resulting in higher antioxidant activities and lower water potential, thus increasing the water deficit tolerance of chickpea under water deficit, especially of cultivated chickpea. We also propose that synthetic cyclitol derivatives can reduce reactive oxygen species and membrane damage and are beneficial for stress adaptation. 相似文献