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991.
992.
Saranna Fanning Aftabul Haque Thibaut Imberdis Valeriya Baru M. Inmaculada Barrasa Silke Nuber Daniel Termine Nagendran Ramalingam Gary P.H. Ho Tallie Noble Jackson Sandoe Yali Lou Dirk Landgraf Yelena Freyzon Gregory Newby Frank Soldner Elizabeth Terry-Kantor Tae-Eun Kim Dennis Selkoe 《Molecular cell》2019,73(5):1001-1014.e8
993.
Dhakal Dipesh Rayamajhi Vijay Mishra Ravindra Sohng Jae Kyung 《Journal of industrial microbiology & biotechnology》2019,46(3-4):385-407
Journal of Industrial Microbiology & Biotechnology - Nocardia spp. are catalase positive, aerobic, and non-motile Gram-positive filamentous bacteria. Many Nocarida spp. have been reported as... 相似文献
994.
Song Mei Ling Kim Keun Tae Motamedi Gholam K. Cho Yong Won 《Sleep and biological rhythms》2019,17(4):447-454
Sleep and Biological Rhythms - Narcoleptics tend to have a low quality of life (QoL). Few studies have compared QoL in narcolepsy against other sleep disorders. The purpose of this study was to... 相似文献
995.
Yalitza Lopez Corcino Shekina Gonzalez Ferrer Luz Eliana Mantilla Sophia Trikeriotis Jin‐Sang Yu Steven Kim Samuel Hansen Jose‐Andres C. Portillo Carlos S. Subauste 《Cellular microbiology》2019,21(10)
Toxoplasma gondii causes retinitis and encephalitis. Avoiding targeting by autophagosomes is key for its survival because T. gondii cannot withstand lysosomal degradation. During invasion of host cells, T. gondii triggers epidermal growth factor receptor (EGFR) signalling enabling the parasite to avoid initial autophagic targeting. However, autophagy is a constitutive process indicating that the parasite may also use a strategy operative beyond invasion to maintain blockade of autophagic targeting. Finding that such a strategy exists would be important because it could lead to inhibition of host cell signalling as a novel approach to kill the parasite in previously infected cells and treat toxoplasmosis. We report that T. gondii induced prolonged EGFR autophosphorylation. This effect was mediated by PKCα/PKCβ ? Src because T. gondii caused prolonged activation of these molecules and their knockdown or incubation with inhibitors of PKCα/PKCβ or Src after host cell invasion impaired sustained EGFR autophosphorylation. Addition of EGFR tyrosine kinase inhibitor (TKI) to previously infected cells led to parasite entrapment by LC3 and LAMP‐1 and pathogen killing dependent on the autophagy proteins ULK1 and Beclin 1 as well as lysosomal enzymes. Administration of gefitinib (EGFR TKI) to mice with ocular and cerebral toxoplasmosis resulted in disease control that was dependent on Beclin 1. Thus, T. gondii promotes its survival through sustained EGFR signalling driven by PKCα/β ? Src, and inhibition of EGFR controls pre‐established toxoplasmosis. 相似文献
996.
Hugh F. Davies Willie Rioli Jos Puruntatameri Willie Roberts Colin Kerinaiua Vivian Kerinauia Kim Brooks Womatakimi Graeme R. Gillespie Brett P. Murphy 《Austral ecology》2019,44(5):868-879
Since European settlement, many granivorous birds of northern Australia's savanna landscapes have declined. One such example, the partridge pigeon (Geophaps smithii), has suffered a significant range contraction, disappearing from at least half of its pre‐European range. Multiple factors have been implicated in this decline, including the loss of traditional Aboriginal burning practices, grazing by large exotic herbivores and predation by feral cats (Felis catus). While populations of partridge pigeon on the Tiwi Islands may be particularly important for the long‐term persistence of this species, they too may be at risk of decline. However, as a reliable method to detect this species has not yet been developed and tested, we lack the ability to identify, at an early stage, the species' decline in a given location or region. This severely limits our capacity to make informed management decisions. Here, we demonstrate that the standard camera trapping approach for native mammal monitoring in northern Australia attained an overall probability of detecting partridge pigeon greater than 0.98. We thus provide a robust estimate of partridge pigeon site occupancy (0.30) on Melville Island, the larger of the two main Tiwi Islands. The information presented here for the partridge pigeon represents a critical first step towards the development of optimal monitoring programmes with which to gauge population trajectories, as well as the response to remedial management actions. In the face of ongoing biodiversity loss, such baseline information is vital for management agencies to make informed decisions and should therefore be sought for as many species as possible. 相似文献
997.
Limnology - Maintaining moderate levels of aquatic plant cover in agricultural reservoirs is an important issue because aquatic plant development is closely related to diverse ecosystem functions,... 相似文献
998.
Han-Wool Kim Byung-Ho Choi 《Computer methods in biomechanics and biomedical engineering》2019,22(3):251-258
The purpose of this study is to measure the failure risk of a crown depending on the cusp angle. Three all-ceramic crown models consisting of CH (high incline), CM (middle incline), and CL (low incline) are designed. Stress is applied to the crown with Loading case-1 (top of cusp tip) and Loading case-2 (middle of cusp ridge) with the use of FEA software. In Loading case-1 and case-2, the CH showed the highest Maximum Principal Stress (MPS) while the CL showed the lowest MPS. The cusp angle is an influential factor affecting stress distribution in dental crowns. 相似文献
999.
Yong‐Han Kim In‐Won Lee Yu‐Jin Jo Nam‐Hyung Kim Suk Namgoong 《Molecular reproduction and development》2019,86(8):972-983
Mammalian oocytes lack centrioles but can generate bipolar spindles using several different mechanisms. For example, mouse oocytes have acentriolar microtubule organization centers (MTOCs) that contain many components of the centrosome, and which initiate microtubule polymerization. On the contrary, human oocytes lack MTOCs and the Ran‐mediated mechanisms may be responsible for spindle assembly. Complete knowledge of the different mechanisms of spindle assembly is lacking in various mammalian oocytes. In this study, we demonstrate that both MTOC‐ and Ran‐mediated microtubule nucleation are required for functional meiotic metaphase I spindle generation in porcine oocytes. Acentriolar MTOC components, including Cep192 and pericentrin, were absent in the germinal vesicle and germinal vesicle breakdown stages. However, they start to colocalize to the spindle microtubules, but are absent in the meiotic spindle poles. Knockdown of Cep192 or inhibition of Polo‐like kinase 1 activity impaired the recruitment of Cep192 and pericentrin to the spindles, impaired microtubule assembly, and decreased the polar body extrusion rate. When the RanGTP gradient was perturbed by the expression of dominant negative or constitutively active Ran mutants, severe defects in microtubule nucleation and cytokinesis were observed, and the localization of MTOC materials in the spindles was abolished. These results demonstrate that the stepwise involvement of MTOC‐ and Ran‐mediated microtubule assembly is crucial for the formation of meiotic spindles in porcine oocytes, indicating the diversity of spindle formation mechanisms among mammalian oocytes. 相似文献
1000.
The lateral resolution of continuous wave (CW) stimulated emission depletion (STED) microscopy is enhanced about 12% by applying annular‐shaped amplitude modulation to the radially polarized excitation beam. A focused annularly filtered radially polarized excitation beam provides a more condensed point spread function (PSF), which contributes to enhance effective STED resolution of CW STED microscopy. Theoretical analysis shows that the FWHM of the effective PSF on the detection plane is smaller than for conventional CW STED. Simulation shows the donut‐shaped PSF of the depletion beam and confocal optics suppress undesired PSF sidelobes. Imaging experiments agree with the simulated resolution improvement. 相似文献