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1.
Silas A. Buck Thomas Steinkellner Despoina Aslanoglou Michael Villeneuve Sai H. Bhatte Victoria C. Childers Sophie A. Rubin Briana R. De Miranda Emma I. O'Leary Elizabeth G. Neureiter Keri J. Fogle Michael J. Palladino Ryan W. Logan Jill R. Glausier Kenneth N. Fish David A. Lewis J. Timothy Greenamyre Brian D. McCabe Claire E. J. Cheetham Thomas S. Hnasko Zachary Freyberg 《Aging cell》2021,20(5)
Age is the greatest risk factor for Parkinson''s disease (PD) which causes progressive loss of dopamine (DA) neurons, with males at greater risk than females. Intriguingly, some DA neurons are more resilient to degeneration than others. Increasing evidence suggests that vesicular glutamate transporter (VGLUT) expression in DA neurons plays a role in this selective vulnerability. We investigated the role of DA neuron VGLUT in sex‐ and age‐related differences in DA neuron vulnerability using the genetically tractable Drosophila model. We found sex differences in age‐related DA neurodegeneration and its associated locomotor behavior, where males exhibit significantly greater decreases in both DA neuron number and locomotion during aging compared with females. We discovered that dynamic changes in DA neuron VGLUT expression mediate these age‐ and sex‐related differences, as a potential compensatory mechanism for diminished DA neurotransmission during aging. Importantly, female Drosophila possess higher levels of VGLUT expression in DA neurons compared with males, and this finding is conserved across flies, rodents, and humans. Moreover, we showed that diminishing VGLUT expression in DA neurons eliminates females'' greater resilience to DA neuron loss across aging. This offers a new mechanism for sex differences in selective DA neuron vulnerability to age‐related DA neurodegeneration. Finally, in mice, we showed that the ability of DA neurons to achieve optimal control over VGLUT expression is essential for DA neuron survival. These findings lay the groundwork for the manipulation of DA neuron VGLUT expression as a novel therapeutic strategy to boost DA neuron resilience to age‐ and PD‐related neurodegeneration. 相似文献
2.
M O Birger E P Grenkova N G Fish T I Zavodnova A N Kuzikov 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1980,(11):46-48
Deoxycholate C. diphtheriae extract was separated into fractions differing in the size of their molecules. Correlation between the molecular weight of each fraction, its specific protein content and its immunogenicity was observed. The high-molecular fraction (mol. wt. exceeding 300,000 daltons) was shown to be the protective somatic antigen of C. diphtheriae. 相似文献
3.
The most effective electrical stimulus to the calf muscles which prevents stasis in the soleal veins during operation was determined. This was subsequently used in a clinical trial and was shown to produce a 92% relative reduction in the incidence of deep vein thrombosis as determined by the 125I-fibrinogen test. 相似文献
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E D Bershadskaia N G Fish P P Shev'ev M A Osipov V I Ogarkov 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1986,(9):32-35
Anabol and blastolysin preparations obtained from L. bulgaricus may contain surface structural components of the initial strain with adhesion activity; of these, one is similar in specificity to L. casei adhesin and the other, to L. plantarum adhesin. The antigenic activity of anabol and blastolysin, evaluated in the immunodiffusion test, does not correlate with their capacity for binding the receptors of susceptible bacterial cells, determined in the Lactobacillus-induced hemagglutination inhibition test. 相似文献
6.
Seventeen alkaliphilic halomonads were examined for the presence of plasmids. Of these, eight strains harbored one or more from 5.3 to 33 kb in size, the first plasmids to be identified from an alkaliphilic halomonad source. Restriction and hybridization analysis revealed three strains that maintained an identical 5.9-kb plasmid which we named pAH1, two that had an identical 33-kb plasmid, and three others, of which one carried two plasmids of 5.3 and 15 kb, the former being designated pAH2. The two final strains maintained plasmids of 15 and 20.5 kb. Restriction mapping of both pAH1 and pAH2 indicated that they have a number of unique restriction sites and are of a small enough size to make them suitable for vector construction. 相似文献
7.
In an institution for the mentally retarded, an uncontrolled study was made on the effects of d-amphetamine, d-amphetamine followed by trifluoperazine, and of combined d-amphetamine and trifluoperazine on stuttering. Of 28 patients to whom d-amphetamine was given, 14 showed improvement after one month''s treatment. Eight more showed improvement when trifluoperazine was given for one month to those who did not improve on d-amphetamine. In many cases, improvement was sustained at least six months after treatment was discontinued.Treatment with d-amphetamine was apparently more effective in patients with functional than with organic retardation. 相似文献
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