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991.
Min-Kyoo Shin Edwin Vázquez-Rosa Yeojung Koh Matasha Dhar Kalyani Chaubey Coral J. Cintrón-Pérez Sarah Barker Emiko Miller Kathryn Franke Maria F. Noterman Divya Seth Rachael S. Allen Cara T. Motz Sriganesh Ramachandra Rao Lara A. Skelton Machelle T. Pardue Steven J. Fliesler Chao Wang Andrew A. Pieper 《Cell》2021,184(10):2715-2732.e23
992.
Ruth F. Itzhaki 《Molecular neurobiology》1994,9(1-3):1-13
Inherited cases of Alzheimer's disease (AD) comprise only a very small proportion of the total. The remainder are of unknown
etiopathogenesis, but they are very probably multifactorial in origin. This article describes studies on four possible factors:
aluminum; viruses—in particular, herpes simplex type I virus (HSV1); defective DNA repair; and head trauma. Specific problems
associated with aluminum, such as inadvertent contamination and its insolubility, have led to some controversy over its usage.
Nonetheless, the effects of aluminum on animals and neuronal cells in culture have been studied intensively. Changes in protein
structure and location in the cell are described, including the finding in this laboratory of a change in τ resembling that
in AD neurofibrillary tangles, and also the lack of appreciable binding of aluminum to DNA. As for HSV1, there has previously
been uncertainty about whether HSV1 DNA is present in human brain. Work in this laboratory using polymerase chain reaction
has shown that HSV1 DNA is present in many normal aged brains and AD brains, but is absent in brains from younger people.
Studies on DNA damage and repair in AD and normal cells are described, and finally, the possible involvement of head trauma
is discussed. 相似文献
993.
994.
Kathryn A. Skelding Jacinta M. Arellano David A. Powis John A. Rostas 《Journal of visualized experiments : JoVE》2014,(84)
Examining molecular mechanisms involved in neuropathological conditions, such as ischemic stroke, can be difficult when using whole animal systems. As such, primary or ''neuronal-like'' cell culture systems are commonly utilized. While these systems are relatively easy to work with, and are useful model systems in which various functional outcomes (such as cell death) can be readily quantified, the examined outcomes and pathways in cultured immature neurons (such as excitotoxicity-mediated cell death pathways) are not necessarily the same as those observed in mature brain, or in intact tissue. Therefore, there is the need to develop models in which cellular mechanisms in mature neural tissue can be examined. We have developed an in vitro technique that can be used to investigate a variety of molecular pathways in intact nervous tissue. The technique described herein utilizes rat cortical tissue, but this technique can be adapted to use tissue from a variety of species (such as mouse, rabbit, guinea pig, and chicken) or brain regions (for example, hippocampus, striatum, etc.). Additionally, a variety of stimulations/treatments can be used (for example, excitotoxic, administration of inhibitors, etc.). In conclusion, the brain slice model described herein can be used to examine a variety of molecular mechanisms involved in excitotoxicity-mediated brain injury. 相似文献
995.
Wensheng Shen § Fuqian Yang ∥ 《Computer methods in biomechanics and biomedical engineering》2013,16(2):115-125
A three-dimensional (3D) multilayer model based on the skin physical structure is developed to investigate the transient thermal response of human skin subject to laser heating. The temperature distribution of the skin is modeled by the bioheat transfer equation, and the influence of laser heating is expressed as a source term where the strength of the source is a product of a Gaussian shaped incident irradiance, an exponentially shaped axial attenuation, and a time function. The water evaporation and diffusion is included in the model by adding two terms regarding the heat loss due to the evaporation and diffusion, where the rate of water evaporation is determined based on the theory of laminar boundary layer. Cryogen spray cooling (CSC) in laser therapy is studied, as well as its effect on the skin thermal response. The time-dependent equation is discretized using the finite difference method with the Crank–Nicholson scheme and the stability of the numerical method is analyzed. The large sparse linear system resulted from discretizing the governing partial differential equation is solved by a GMRES solver and the expected simulation results are obtained. 相似文献
996.
A. Lonard E. D. Lonard G. B. Gerber M. C. Crutzen-Fayt F. Richard J. G. Gueulette N. B. Akhmatullina 《Mutation Research - Genetic Toxicology and Environmental Mutagenesis》1998,420(1-3)
Experiments were performed with human plasma irradiated in vitro or in vivo in order to evaluate the extent to which clastogenic factors might disturb the adaptive response to DNA-damaging factors currently studied in our laboratory. The studies were carried out with plasma isolated from whole blood given 4 Gy of X-rays in vitro and with plasma from people receiving local radiotherapy at a total dose of about 60 Gy gamma rays. Addition of irradiated plasma to culture medium did not result in a statistically significant increase in structural aberrations in chromosomes of non-irradiated normal blood. 相似文献
997.
Chaosheng Lu Bicheng Chen Congcong Chen Haiyan Li Dan Wang Yi Tan Huachun Weng 《Journal of cellular and molecular medicine》2020,24(2):1700-1712
Circular RNAs are a class of widespread and diverse endogenous RNAs that may regulate gene expression in various diseases, but their regulation and function in hypertensive renal injury remain unclear. In this study, we generated ribosomal‐depleted RNA sequencing data from normal mouse kidneys and from injured mouse kidneys induced by deoxycorticosterone acetate‐salt hypertension and identified at least 4900 circRNA candidates. A total of 124 of these circRNAs were differentially expressed between the normal and injured kidneys. Furthermore, we characterized one abundant circRNA, termed circNr1h4, which is derived from the Nr1h4 gene and significantly down‐regulated in the injured kidneys. RNA sequencing data and qPCR analysis also showed many microRNAs and mRNAs, including miR‐155‐5p and fatty acid reductase 1 (Far1), were differentially expressed between the normal and injured kidney and related to circNr1h4. In vitro, the silencing of circNr1h4 or overexpression of miR‐155‐5p significantly decreased Far1 levels and increased reactive oxygen species. Mechanistic investigations indicated that circNr1h4 acts as a competing endogenous RNA for miR‐155‐5p, leading to regulation of its target gene Far1. Our study provides novel insight into the molecular mechanisms underlying kidney injury in hypertension, which will be required to develop therapeutic strategies of targeting circRNAs for hypertensive kidney injury. 相似文献
998.
Ischemic injury to the kidneys is a prevalent clinical problem, contributing importantly to chronic kidney disease. Yet, underlying molecular mechanisms are elusive. To address the possible role of autophagy, we engineered a novel strain of mice harboring a ubiquitously expressed CAG-RFP-EGFP-LC3 transgene. Using this tool, we examined the post-ischemic kidney and detailed the dynamics of renal tubular epithelial autophagy. In addition, we defined the role of MTOR in the resolution of autophagy during epithelial survival and kidney repair. 相似文献
999.
《Free radical research》2013,47(8):925-935
AbstractThe present study tested the cytoprotective effect of methyleugenol in an in vivo ischemia model (i.e. middle cerebral artery occlusion (MCAO) for 1.5 h and subsequent reperfusion for 24 h) and further investigated its mechanism of action in in vitro cerebral ischemic models. When applied shortly after reperfusion, methyleugenol largely reduced cerebral ischemic injury. Methyleugenol decreased the caspase-3 activation and death of cultured cerebral cortical neurons caused by oxygen-glucose deprivation (OGD) for 1 h and subsequent re-oxygenation for 24 h. Methyleugenol markedly reduced superoxide generation in the ischemic brain and decreased the intracellular oxidative stress caused by OGD/re-oxygenation. It was found that methyleugenol elevated the activities of superoxide dismutase and catalase. Further, methyleugenol inhibited the production of nitric oxide and decreased the protein expression of inducible nitric oxide synthase. Methyleugenol down-regulated the production of pro-inflammatory cytokines in the ischemic brain as well as in immunostimulated mixed glial cells. The results indicate that methyleugenol could be useful for the treatment of ischemia/inflammation-related diseases. 相似文献
1000.
Gianmarco Rinaldi Erica Pranzini Joke Van Elsen Dorien Broekaert Cornelius M. Funk Mélanie Planque Ginevra Doglioni Patricia Altea-Manzano Matteo Rossi Vincent Geldhof Shao Thing Teoh Christina Ross Kent W. Hunter Sophia Y. Lunt Thomas G.P. Grünewald Sarah-Maria Fendt 《Molecular cell》2021,81(2):386-397.e7