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101.
Sperm storage and spermatozoa interaction with epithelial cells in oviduct of Chinese soft‐shelled turtle,Pelodiscus sinensis
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Linli Zhang Yuan Le Yasir Waqas Wei Chen Qian Zhang Shakeeb Ullah Tengfei Liu Lisi Hu Quanfu Li Ping Yang 《Ecology and evolution》2015,5(15):3023-3030
Spermatozoa are known to be stored within the female genital tract after mating in various species to optimize timing of reproductive events such as copulation, fertilization, and ovulation. The mechanism supporting long‐term sperm storage is still unclear in turtles. The aim of this study was to investigate the interaction between the spermatozoa and oviduct in Chinese soft‐shelled turtle by light and electron microscopy to reveal the potential cytological mechanism of long‐term sperm storage. Spermatozoa were stored in isthmus, uterine, and vagina of the oviduct throughout the year, indicating long‐term sperm storage in vivo. Sperm heads were always embedded among the cilia and even intercalated into the apical hollowness of the ciliated cells in the oviduct mucosal epithelium. The stored spermatozoa could also gather in the gland conduit. There was no lysosome distribution around the hollowness of the ciliated cell, suggesting that the ciliated cells of the oviduct can support the spermatozoa instead of phagocytosing them in the oviduct. Immune cells were sparse in the epithelium and lamina propria of oviduct, although few were found inside the blood vessel of mucosa, which may be an indication of immune tolerance during sperm storage in the oviduct of the soft‐shelled turtle. These characteristics developed in the turtle benefited spermatozoa survival for a long time as extraneous cells in the oviduct of this species. These findings would help to improve the understanding of reproductive regularity and develop strategies of species conservation in the turtle. The Chinese soft‐shelled turtle may be a potential model for uncovering the mechanism behind the sperm storage phenomenon. 相似文献
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Lim Ming Han Zaiton Haron Khairulzan Yahya Suhaimi Abu Bakar Mohamad Ngasri Dimon 《PloS one》2015,10(4)
Strategic noise mapping provides important information for noise impact assessment and noise abatement. However, producing reliable strategic noise mapping in a dynamic, complex working environment is difficult. This study proposes the implementation of the random walk approach as a new stochastic technique to simulate noise mapping and to predict the noise exposure level in a workplace. A stochastic simulation framework and software, namely RW-eNMS, were developed to facilitate the random walk approach in noise mapping prediction. This framework considers the randomness and complexity of machinery operation and noise emission levels. Also, it assesses the impact of noise on the workers and the surrounding environment. For data validation, three case studies were conducted to check the accuracy of the prediction data and to determine the efficiency and effectiveness of this approach. The results showed high accuracy of prediction results together with a majority of absolute differences of less than 2 dBA; also, the predicted noise doses were mostly in the range of measurement. Therefore, the random walk approach was effective in dealing with environmental noises. It could predict strategic noise mapping to facilitate noise monitoring and noise control in the workplaces. 相似文献
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Arenaviruses, Junin and Machupo are pathogenic viruses in regions of South America including Argentina and Bolivia causing haemorrhagic fever among humans. They have been transmitted to humans through mouse causing chronic illness with high mortality. Therefore, it is of interest to acquittance the molecular docking analysis data of FDA approved drugs with the glycoprotein from Junin and Machupo viruses for consideration in drug discovery. Thus, we report the optimal binding features of MK-3207 and Dihydro ergotamine with the protein target for further validation and consideration. 相似文献
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Abrar Aljiboury Amra Mujcic Erin Curtis Thomas Cammerino Denise Magny Yiling Lan Michael Bates Judy Freshour Yasir H. Ahmed-Braimeh Heidi Hehnly 《Molecular biology of the cell》2022,33(9)
Polo-like-kinase (PLK) 1 activity is associated with maintaining the functional and physical properties of the centrosome’s pericentriolar matrix (PCM). In this study, we use a multimodal approach of human cells (HeLa), zebrafish embryos, and phylogenic analysis to test the role of a PLK1 binding protein, cenexin, in regulating the PCM. Our studies identify that cenexin is required for tempering microtubule nucleation by maintaining PCM cohesion in a PLK1-dependent manner. PCM architecture in cenexin-depleted zebrafish embryos was rescued with wild-type human cenexin, but not with a C-terminal cenexin mutant (S796A) deficient in PLK1 binding. We propose a model where cenexin’s C terminus acts in a conserved manner in eukaryotes, excluding nematodes and arthropods, to sequester PLK1 that limits PCM substrate phosphorylation events required for PCM cohesion. 相似文献
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Martín Battaglia Wade Thomason John H. Fike Gregory K. Evanylo Moritz von Cossel Emre Babur Yasir Iqbal Andre A. Diatta 《Global Change Biology Bioenergy》2021,13(1):45-57
Biofuel production from crop residues is widely recognized as an essential component of developing a bioeconomy, but the removal of crop residues still raises many questions about the sustainability of the cropping system. Therefore, this study reviews the sustainability effects of crop residues removal for biofuel production in terms of crop production, soil health and greenhouse gas emissions. Most studies found little evidence that residue management had long‐term impacts on grain yield unless the available water is limited. In years when water was not limiting, corn and wheat removal rates ≥90% produced similar or greater grain yield than no removal in most studies. Conversely, when water was limiting, corn grain yield decreased up to 21% with stover removal ≥90% in some studies. Changes in soil organic fractions and nutrients depended largely on the amount of residue returned, soil depth and texture, slope and tillage. Reductions in organic fractions occurred primarily with complete stover removal, in the top 15–30 cm in fine‐textured soils. Soil erosion, water runoff and leaching of nutrients such as total nitrogen (N) and extractable soil potassium decreased when no more than 30% of crop residues were removed. Stover management effects on soil bulk density varied considerably depending on soil layer, and residue and tillage management, with removal rates of less than 50% helping to maintain the soil aggregate stability. Reductions in CO2 and N2O fluxes typically occurred following complete residue removal. The use of wheat straw typically increased CH4 emissions, and above or equal to 8 Mg/ha wheat straw led to the largest CO2 and N2O emissions, regardless of N rates. Before using crop residues for biofuel production, it should therefore always be checked whether neutral to positive sustainability effects can be maintained under the site‐specific conditions. 相似文献
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Wilson Thau Lym Yong Jamie Yan Yung Chin Vun Yee Thien Suhaimi Yasir 《Phycological Research》2014,62(4):316-321
This study aimed to evaluate and compare the quality of κ‐carrageenan obtained from tissue‐cultured and field‐cultured Kappaphycus alvarezii. Carrageenan properties including yield, viscosity, gel strength and sulfate content were studied. After 60 days of cultivation, tissue‐cultured K. alvarezii showed a higher growth rate (6.3 ± 0.01% day?1) than field‐cultured seedlings (3.4 ± 0.3% day?1). The obtained carrageenan yield from tissue‐cultured (67.3 ± 16.4%) was higher than field‐cultured K. alvarezii (51.5 ± 21.0%). Gel viscosity of carrageenans from tissue‐cultured K. alvarezii (1280.0 ± 25.0 cP) was found significantly higher than field‐cultured samples (87.8 ± 20.9 cP). The 1.5% gel solution of tissue‐cultured and field‐cultured K. alvarezii exhibited gel strengths of 703.5 ± 14.1 and 288.3 ± 19.3 g cm?2, respectively. The average sulfate content of carrageenans was found to be significantly different between tissue‐cultured and field‐cultured K. alvarezii with 34.2 ± 10.9 and 7.5 ± 6.7%, respectively. Tissue culture is recommended to produce high quality seedlings by providing optimized culture conditions to the seaweed. This approach can serve as an alternative way to solve the seedling shortage problems currently faced by the seaweed industry. 相似文献
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Marc A. Becker Yasir H. Ibrahim Annabell S. Oh Dedra H. Fagan Sara A. Byron Aaron L. Sarver Adrian V. Lee Leslie M. Shaw Cheng Fan Charles M. Perou Douglas Yee 《PloS one》2016,11(3)
Therapies targeting the type I insulin-like growth factor receptor (IGF-1R) have not been developed with predictive biomarkers to identify tumors with receptor activation. We have previously shown that the insulin receptor substrate (IRS) adaptor proteins are necessary for linking IGF1R to downstream signaling pathways and the malignant phenotype in breast cancer cells. The purpose of this study was to identify gene expression profiles downstream of IGF1R and its two adaptor proteins. IRS-null breast cancer cells (T47D-YA) were engineered to express IRS-1 or IRS-2 alone and their ability to mediate IGF ligand-induced proliferation, motility, and gene expression determined. Global gene expression signatures reflecting IRS adaptor specific and primary vs. secondary ligand response were derived (Early IRS-1, Late IRS-1, Early IRS-2 and Late IRS-2) and functional pathway analysis examined. IRS isoforms mediated distinct gene expression profiles, functional pathways, and breast cancer subtype association. For example, IRS-1/2-induced TGFb2 expression and blockade of TGFb2 abrogated IGF-induced cell migration. In addition, the prognostic value of IRS proteins was significant in the luminal B breast tumor subtype. Univariate and multivariate analyses confirmed that IRS adaptor signatures correlated with poor outcome as measured by recurrence-free and overall survival. Thus, IRS adaptor protein expression is required for IGF ligand responses in breast cancer cells. IRS-specific gene signatures represent accurate surrogates of IGF activity and could predict response to anti-IGF therapy in breast cancer. 相似文献