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1.
The blood-brain barrier in and out of cell culture. 总被引:1,自引:0,他引:1
L L Rubin 《Current opinion in neurobiology》1991,1(3):360-363
During the past year, the blood-brain barrier has received much attention from neurobiologists and neurologists and real progress has been made in establishing cell-culture model systems that should make future studies more simple. Confusion about the development of the blood-brain barrier, and the exact role of astrocytes in this process persist, but these issues should soon be clarified. 相似文献
2.
Nicéia Spanholi Calgaroto Gustavo Roberto Thomé Pauline da Costa Jucimara Baldissareli Fátima Abdala Hussein Roberta Schmatz Maribel A. Rubin Cristiane Signor Daniela Aymone Ribeiro Fabiano Barbosa Carvalho Lizielle Souza de Oliveira Luciane Belmonte Pereira Vera Maria Morsch Maria Rosa Chitolina Schetinger 《Cell biochemistry and function》2014,32(6):502-510
Diabetes is associated with long‐term complications in the brain and reduced cognitive ability. Vitamin D3 (VD3) appears to be involved in the amelioration of hyperglycaemia in streptozotocin (STZ)‐induced diabetic rats. Our aim was to analyse the potential of VD3 in avoiding brain damage through evaluation of acetylcholinesterase (AChE), Na+K+‐adenosine triphosphatase (ATPase) and delta aminolevulinate dehydratase (δ‐ALA‐D) activities and thiobarbituric acid reactive substance (TBARS) levels from cerebral cortex, as well as memory in STZ‐induced diabetic rats. Animals were divided into eight groups (n = 5): control/saline, control/metformin (Metf), control/VD3, control/Metf + VD3, diabetic/saline, diabetic/Metf, diabetic/VD3 and diabetic/Metf + VD3. Thirty days after treatment, animals were submitted to contextual fear‐conditioning and open‐field behavioural tests, after which they were sacrificed and the cerebral cortex was dissected. Our results demonstrate a significant memory deficit, an increase in AChE activity and TBARS levels and a decrease in δ‐ALA‐D and Na+K+‐ATPase activities in diabetic rats when compared with the controls. Treatment of diabetic rats with Metf and VD3 prevented the increase in AChE activity when compared with the diabetic/saline group. In treated diabetic rats, the decrease in Na+K+‐ATPase was reverted when compared with non‐treated rats, but the increase in δ‐ALA‐D activity was not. VD3 prevented diabetes‐induced TBARS level and improved memory. Our results show that VD3 can avoid cognitive deficit through prevention of changes in important enzymes such as Na+K+‐ATPase and AChE in cerebral cortex in type 1 diabetic rats. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
3.
Anna-Karin H. Hultg?rd-Ekwall Vincent Couloigner Kristofer Rubin Helge Rask-Andersen 《The journal of histochemistry and cytochemistry》2003,51(11):1491-1500
The human endolymphatic duct (ED) and sac of the inner ear have been suggested to control endolymph volume and pressure. However, the physiological mechanisms for these processes remain obscure. We investigated the organization of the periductal interstitial connective tissue cells and extracellular matrix (ECM) in four freshly fixed human EDs by transmission electron microscopy and by immunohistochemistry. The unique surgical material allowed a greatly improved structural and epitopic preservation of tissue. Periductal connective tissue cells formed frequent intercellular contacts and focally occurring electron-dense contacts to ECM structures, creating a complex tissue network. The connective tissue cells also formed contacts with the basal lamina of the ED epithelium and the bone matrix, connecting the ED with the surrounding bone of the vestibular aqueduct. The interstitial connective tissue cells were non-endothelial and non-smooth muscle fibroblastoid cells. We suggest that the ED tissue network forms a functional mechanical entity that takes part in the control of inner ear fluid pressure and endolymph resorption. 相似文献
4.
Matthew R. Ginsberg Robert A. Rubin Tatiana Falcone Angela H. Ting Marvin R. Natowicz 《PloS one》2012,7(9)
BackgroundAutism is a common neurodevelopmental syndrome. Numerous rare genetic etiologies are reported; most cases are idiopathic.Conclusions/SignificanceThis work highlights two largely unrecognized molecular pathophysiological themes in autism and suggests differing molecular bases for autism behavioral endophenotypes. 相似文献
5.
T. K. Antal E. E. Graevskaya D. N. Matorin A. A. Volgusheva V. A. Osipov T. E. Krendeleva A. B. Rubin 《Biophysics》2009,54(4):481-485
The effect of methylmercury and copper ions on the kinetics of light induction and dark relaxation of the variable fluorescence of chlorophyll a has been studied on cultures of unicellular alga Chlamydomonas moewusii. Methylmercury was effective at much lower levels. The toxicants at concentrations that did not decrease the photochemical activity of PS II (F v/F m) did affect the electron transport on the acceptor side of PS II, nonphotochemical quenching of excitation in the antenna, and reoxidation of the quinone pool. Our results indicate that this approach can be used for detecting the changes in plant cells at the early stages of toxicant action. 相似文献
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Giardia lamblia cysts were inactivated in water with ozone at pH 7.0 and 5 and 25 degrees C. The concentration-time products for 99% inactivation were 0.53 and 0.17 mg-min/liter at 5 and 25 degrees C, respectively. These products were significantly lower than those reported for chlorine. 相似文献
8.
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
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