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101.
Veith Weilnhammer Merve Fritsch Meera Chikermane Anna-Lena Eckert Katharina Kanthak Heiner Stuke Jakob Kaminski Philipp Sterzer 《Current biology : CB》2021,31(13):2868-2880.e8
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A total of 270 soil samples from 30 different habitats in 10 geographic regions of California were evaluated for the presence of rhabditid entomopathogenic nematodes. Nematodes were isolated from 26.3% of the samples. The recovered isolates were identified as Steinernema carpocapsae, S. feltiae, S. kraussei, S. longicaudum, S. oregonense, Heterorhabditis marelatus and H.bacteriophora. Among the steinernematids, S. kraussei and S. feltiae were the most commonly encountered species, generally occurring in acidic soils high in organic matter. Among the heterorhabditids, H. bacteriophora was isolated along the southern coast, whereas H. marelatus was recovered along the northern coast of California. Steinernematids were recovered from coniferous forests, oak woodlands and grasslands whereas heterorhabditids were isolated from coastal marshes. 相似文献
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Evolution and ecology are essential to an understanding of biology, but questions remain as to when and how young children can learn about these concepts. The concept of adaptation represents an opportunity for children to engage with these ideas, and this article presents several lessons used to teach adaptation to children aged three through six at a summer Science Technology Engineering Art and Mathematics camp. The lessons incorporate interactive yarn stories to illustrate particular adaptations in three biomes: desert, arctic tundra, and deciduous forest. The yarn stories also introduce environmental features and particular organisms that are used in subsequent investigations. Examples and assessment data from preschool children in this camp are used to illustrate young children’s emerging understandings of adaptation throughout these lessons. 相似文献
107.
Zafer Sahin Merve Ertas Barkın Berk Sevde Nur Biltekin Leyla Yurttas Seref Demirayak 《Bioorganic & medicinal chemistry》2018,26(8):1986-1995
Steroidal and non-steroidal aromatase inhibitors target the suppression of estrogen biosynthesis in the treatment of breast cancer. Researchers have increasingly focused on developing non-steroidal derivatives for their potential clinical use avoiding steroidal side-effects.Non-steroidal derivatives generally have planar aromatic structures attached to the azole ring system. One part of this ring system comprises functional groups that inhibit aromatization through the coordination of the haem group of the aromatase enzyme. Replacement of the triazole ring system and development of aromatic/cyclic structures of the side chain can increase selectivity over aromatase enzyme inhibition.In this study, 4-(aryl/heteroaryl)-2-(pyrimidin-2-yl)thiazole derivatives were synthesized and physical analyses and structural determination studies were performed. The IC50 values were determined by a fluorescence-based aromatase inhibition assay and compound 1 (4-(2-hydroxyphenyl)-2-(pyrimidine-2-yl)thiazole) were found potent inhibitor of enzyme (IC50:0.42?nM). Then, their antiproliferative activity over MCF-7 and HEK-293 cell lines was evaluated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Compounds 1, 7, 8, 13, 15, 18, 21 were active against MCF-7 breast cancer cells. Lastly, a series of docking experiments were undertaken to analyze the crystal structure of human placental aromatase and identify the possible interactions between the most active structure and the active site. 相似文献
108.
Didem Şöhretoğlu Merve Yüzbaşıoğlu Baran Randolph Arroo Ayşe Kuruüzüm-Uz 《Phytochemistry Reviews》2018,17(5):973-1005
Polydatin (PLD), the 3-O-β-glucopyranoside of the well-known stilbenoid compound resveratrol, is a major compound of Fallopia japonica (Houtt.) R. Decr. (Japanese knotweed), which is widely used in traditional Chinese medicine to treat infection, inflammatory diseases and circulatory problems. It has shown a wide range of biological activities including anti-inflammatory, anti-oxidant, anti-cancer, neuroprotective, hepatoprotective, nephroprotective and immunostimulatory effects. Although resveratrol has similar beneficial effects, its low bioavailability has remained a problem. Glycosylation increases solubility of resveratrol in an aqueous environment, thus improving its bioavailability. This has led to a growing interest in PLD. Promising results obtained from bioactivity studies have boosted an intense research on this compound. The aim of this review is to give a comprehensive overview of the botanical sources, pharmacology, biosynthesis, biotechnological production, and bioactivities of PLD, and to discuss clinical studies on this compound. 相似文献
109.
F. van Kesteren M. S. van Mourik E. M. A. Wiegerinck J. Vendrik J. J. Piek J. G. Tijssen K. T. Koch J. P. S. Henriques J. J. Wykrzykowska R. J. de Winter A. H. G. Driessen A. Kaya R. N. Planken M. M. Vis J. Baan 《Netherlands heart journal》2018,26(9):445-453
Aim
In the evolving field of transcatheter aortic valve implantations (TAVI) we aimed to gain insight into trends in patient and procedural characteristics as well as clinical outcome over an 8?year period in a real-world TAVI population.Methods
We performed a single-centre retrospective analysis of 1,011 consecutive patients in a prospectively acquired database. We divided the cohort into tertiles of 337 patients; first interval: January 2009–March 2013, second interval: March 2013–March 2015, third interval: March 2015–October 2016.Results
Over time, a clear shift in patient selection was noticeable towards lower surgical risks including Society of Thoracic Surgeons predicted risk of mortality score and comorbidity. The frequency of transfemoral TAVI increased (from 66.5 to 77.4%, p?=?0.0015). Device success improved (from 62.0 to 91.5%, p?<?0.0001) as did the frequency of symptomatic relief (≥1 New York Heart Association class difference) (from 73.8 to 87.1%, p?=?0.00025). Complication rates decreased, including in-hospital stroke (from 5.0 to 2.1%, p?=?0.033) and pacemaker implantations (from 10.1 to 5.9%, p?=?0.033). Thirty-day mortality decreased (from 11.0 to 2.4%, p?<?0.0001); after adjustment for patient characteristics, a mortality-risk reduction of 72% was observed (adjusted hazard ratio [HR]: 0.28, 95% confidence interval [CI]: 0.13–0.62). One-year mortality rates decreased (from 23.4 to 11.4%), but this was no longer significant after a landmark point was set at 30 days (mortality from 31 days until 1 year) (adjusted HR: 0.69, 95% CI: 0.41–1.16, p?=?0.16).Conclusion
A clear shift towards a lower-risk TAVI population and improved clinical outcome was observed over an 8?year period. Survival after TAVI improved impressively, mainly as a consequence of decreased 30-day mortality.110.
The Role of Epigenetic Regulation and Pluripotency‐Related MicroRNAs in Differentiation of Pancreatic Stem Cells to Beta Cells
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Ediz Coskun Merve Ercin Selda Gezginci‐Oktayoglu 《Journal of cellular biochemistry》2018,119(1):455-467
In this study, we aimed to research the effects of class‐I HDACs and glucose on differentiation of pancreatic islet derived mesenchymal stem cells (PI‐MSCs) to beta cells. Beta cell differentiation determined by flow cytometric analysis and gene expression levels of PDX1, PAX4, PAX6, NKX6.1, NGN3, INS2, and GLUT2. As a result the valproic acid, is an inhibitor of class‐I HDACs, caused the highest beta cell differentiation in PI‐MSCs. However, the cells in this group were at early stages of differentiation. Glucose co‐administration to this group carried the differentiation to higher levels, but these newly formed beta cells were not functional. Moreover, reduction in the levels of pluripotency factors that Oct3/4, c‐Myc, and Nanog were parallel to beta cell differentiation. Also, the levels of HDAC1 and acetylated H3/H4 were increased and methylated H3 was decreased by VPA treatment. In addition, we have detected over expression in genes of miR‐18a‐5p, miR‐19b‐5p, miR‐30d‐3p, miR‐124, miR‐146a‐5p, miR‐184, miR‐335, and miR‐433‐5p in parallel to beta cell differentiation. As the conclusion, this study is important for understanding the epigenetic mechanism that controls the beta cell differentation and it suggests new molecules that can be used for diagnosis, and treatment of diabetes. J. Cell. Biochem. 119: 455–467, 2018. © 2017 Wiley Periodicals, Inc. 相似文献