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11.
Differential effect of three-repeat and four-repeat tau on mitochondrial axonal transport 总被引:1,自引:0,他引:1
Will Stoothoff† Phillip B. Jones Tara L. Spires-Jones Daniel Joyner Ekta Chhabra Kathryn Bercury‡ Zhanyun Fan Hong Xie Brian Bacskai Jon Edd§ Daniel Irimia§ Bradley T. Hyman 《Journal of neurochemistry》2009,111(2):417-427
Tau protein is present in six different splice forms in the human brain and interacts with microtubules via either 3 or 4 microtubule binding repeats. An increased ratio of 3 repeat to 4 repeat isoforms is associated with neurodegeneration in inherited forms of frontotemporal dementia. Tau over-expression diminishes axonal transport in several systems, but differential effects of 3 repeat and 4 repeat isoforms have not been studied. We examined the effects of tau on mitochondrial transport and found that both 3 repeat and 4 repeat tau change normal mitochondrial distribution within the cell body and reduce mitochondrial localization to axons; 4 repeat tau has a greater effect than 3 repeat tau. Further, we observed that the 3 repeat and 4 repeat tau cause different alterations in retrograde and anterograde transport dynamics with 3 repeat tau having a slightly stronger effect on axon transport dynamics. Our results indicate that tau-induced changes in axonal transport may be an underlying theme in neurodegenerative diseases associated with isoform specific changes in tau's interaction with microtubules. 相似文献
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William J. Sutherland Rosalind Aveling Thomas M. Brooks Mick Clout Lynn V. Dicks Liz Fellman Erica Fleishman David W. Gibbons Brandon Keim Fiona Lickorish Kathryn A. Monk Diana Mortimer Lloyd S. Peck Jules Pretty Johan Rockström Jon Paul Rodríguez Rebecca K. Smith Mark D. Spalding Femke H. Tonneijck Andrew R. Watkinson 《Trends in ecology & evolution》2014
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15.
Jing Chen Lihong Qi Zhen Xia Mei Shen Xin Shen Jian Mei Kathryn DeRiemer Zheng’an Yuan 《PloS one》2013,8(11)
Background
Migration is a major challenge to tuberculosis (TB) control worldwide. TB treatment requires multiple drugs for at least six months. Some TB patients default before completing their treatment regimen, which can lead to ongoing infectiousness and drug resistance.Methods
We conducted a retrospective analysis of 29,943 active TB cases among urban migrants that were reported between 2000 to 2008 in Shanghai, China. We used logistic regression models to identify factors independently associated with treatment defaults in TB patients among urban migrants during 2005-2008.Results
Fifty-two percent of the total TB patients reported in Shanghai during the study period were among urban migrants. Three factors increased the odds of a treatment default: case management using self-administered therapy (OR, 5.84, 95% CI, 3.14-10.86, p<0.0005), being a retreatment case (OR, 1.47, 95% CI, 1.25-1.71, p<0.0005), and age >60 years old (OR, 1.33, 95% CI, 1.05-1.67, p=0.017). The presence of a cavity in the initial chest radiograph decreased the odds for a treatment default (OR, 0.87, 95% CI, 0.77-0.97, p=0.015), as did migration from central China (OR, 0.85, 95% CI, 0.73-0.99, p=0.042), case management by family members (OR, 0.73, 95% CI 0.66-0.81, p<0.0005), and the combination of case detection by a required physical exam and case management by health care staff (OR, 0.64, 95% CI, 0.45-0.93, p=0.019).Conclusion
Among TB patients who were urban migrants in Shanghai, case management using self-administered therapy was the strongest modifiable risk factor that was independently associated with treatment defaults. Interventions that target retreated TB cases could also reduce treatment defaults among urban migrants. Health departments should develop effective measures to prevent treatment defaults among urban migrants, to ensure completion of therapy among urban migrants who move between cities and provinces, and to improve reporting of treatment outcomes. 相似文献16.
Robert G. Sheath JoAnn M. Burkholder Mary O. Morison Alan D. Steinman Kathryn L. VanAlstyne 《Journal of phycology》1986,22(4):567-570
A spring-fed, headwater stream in central Rhode Island was examined during the period from June to October, 1979 to 1982. In the first two summers, a dense riparian canopy reduced the light penetration at the stream surface to a range of 5 to 18% of incident radiation. The lotic macroalgal community during this period was limited to 1 to 4 species covering < 1 to 35% of the stream bottom. However, in June and July, 1981, the surrounding leaf canopy was removed by a massive gypsy moth larval outbreak. Light penetration to the stream during this summer increased to 73% by early July, thereby resulting in a rise in water temperatures by 3.7°C. Even though there was a partial regrowth of leaves in late July and August of 1981, macroalgal cover values continued to rise to an early August peak of 80%. During the third summer, 88% of the macroalgal abundance could be attributed to illumination and water temperature. The filamentous diatom Funotia pectinalis ( O.F. Müll.) Rabh. was the predominant species in the midsummer of all four years, accounting for at least 60% of the total cover. In 1981. an important taxon was the desmid Hyalotheca dissiliens (S. Smith) Bréb., a species which was not seen in other years. A less severe gypsy moth defoliation occurred in 1982 but did not produce significant differences in light, temperature or macroalgal cover from 1979 and 1980. The results indicate that light and temperature can be limiting during the summer in spring-fed, headwater streams and that seed populations of some species are present in undetect-able levels during these periods of suboptimal growth conditions. In addition, it appears that stream macroalgal communities can be quite resilient, recovering rapidly following a major perturbation . 相似文献
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Effects of roads and land use on frog distributions across spatial scales and regions in the Eastern and Central United States 下载免费PDF全文
David M. Marsh Bradley J. Cosentino Kara S. Jones Joseph J. Apodaca Karen H. Beard Jane Margaret Bell Christine Bozarth Derrick Carper Julie F. Charbonnier Andreia Dantas Elizabeth A. Forys Miran Foster Jaquelyn General Kristen S. Genet Macie Hanneken Kyle R. Hess Shane A. Hill Faisal Iqbal Nancy E. Karraker Eran S. Kilpatrick Tom A. Langen James Langford Kathryn Lauer Alison J. McCarthy Joseph Neale Saumya Patel Austin Patton Cherie Southwick Nathaniel Stearrett Nicholas Steijn Mohammad Tasleem Joseph M. Taylor James R. Vonesh 《Diversity & distributions》2017,23(2):158-170
19.
Eugene M. Rinchik Terry Magnuson Bernadette Holdener-Kenny Gavin Kelsey Albert Bianchi Claudio J. Conti Fran?ois Chartier Kathryn A. Brown Stephen D. M. Brown Josephine Peters 《Mammalian genome》1992,3(Z1):S104-S120
Chair of Committee for Mouse Chromosome 7 相似文献
20.
John F. Brandts Richard D. Taverna Easwara Sadasivan Kathryn A. Lysko 《生物化学与生物物理学报:生物膜》1978,512(3):566-578
Differential scanning calorimetry has been used to study several structural transitions of the human erythrocyte membrane. Earlier studies have shown that one of these transitions (the A transition) is due to the thermal unfolding of spectrin on the membrane. In this paper, it is shown that two of the other transitions (B and C) exhibit a high sensitivity to a local anesthetic, benzyl alcohol. Increasing the ionic strength of the suspending medium results in a splitting of the B transition into two independent transitions (B1 and B2). It is found that one of these (B2) is associated with titrating groups, since the midpoint for the transitions shifts by about 20°C, with an apparent near 7.5. Extensive bilateral proteolysis by papain causes a drastic decrease in the size of all transitions except the C transition, which remains unaltered. On the other hand, treatment with phospholipase A2 largely affects the C transition, causing its disappearance. Because of the lack of sensitivity to proteolysis and the high sensitivity to phospholipase, it appears that the C transition has a large extent of ‘lipid involvement’. It might result from the melting of a small fraction of phospholipid which exists in a crystalline state under physiological conditions. Alternatively, the C transition could arise from changes in protein-lipid interactions or from lipid-dependent changes in protein-protein interactions, providing one assumes that only protease-resistant portions of membrane proteins are participating. 相似文献