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21.
Transcriptome changes during intestinal cell differentiation 总被引:4,自引:0,他引:4
22.
Uncoupling protein-2 prevents neuronal death and diminishes brain dysfunction after stroke and brain trauma 总被引:28,自引:0,他引:28
Mattiasson G Shamloo M Gido G Mathi K Tomasevic G Yi S Warden CH Castilho RF Melcher T Gonzalez-Zulueta M Nikolich K Wieloch T 《Nature medicine》2003,9(8):1062-1068
Whereas uncoupling protein 1 (UCP-1) is clearly involved in thermogenesis, the role of UCP-2 is less clear. Using hybridization, cloning techniques and cDNA array analysis to identify inducible neuroprotective genes, we found that neuronal survival correlates with increased expression of Ucp2. In mice overexpressing human UCP-2, brain damage was diminished after experimental stroke and traumatic brain injury, and neurological recovery was enhanced. In cultured cortical neurons, UCP-2 reduced cell death and inhibited caspase-3 activation induced by oxygen and glucose deprivation. Mild mitochondrial uncoupling by 2,4-dinitrophenol (DNP) reduced neuronal death, and UCP-2 activity was enhanced by palmitic acid in isolated mitochondria. Also in isolated mitochondria, UCP-2 shifted the release of reactive oxygen species from the mitochondrial matrix to the extramitochondrial space. We propose that UCP-2 is an inducible protein that is neuroprotective by activating cellular redox signaling or by inducing mild mitochondrial uncoupling that prevents the release of apoptogenic proteins. 相似文献
23.
Discrimination of grasshopper (Orthoptera: Acrididae) diet and niche overlap using next‐generation sequencing of gut contents
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Beverly McClenaghan Joel F. Gibson Shadi Shokralla Mehrdad Hajibabaei 《Ecology and evolution》2015,5(15):3046-3055
Species of grasshopper have been divided into three diet classifications based on mandible morphology: forbivorous (specialist on forbs), graminivorous (specialist on grasses), and mixed feeding (broad‐scale generalists). For example, Melanoplus bivittatus and Dissosteira carolina are presumed to be broad‐scale generalists, Chortophaga viridifasciata is a specialist on grasses, and Melanoplus femurrubrum is a specialist on forbs. These classifications, however, have not been verified in the wild. Multiple specimens of these four species were collected, and diet analysis was performed using DNA metabarcoding of the gut contents. The rbcLa gene region was amplified and sequenced using Illumina MiSeq sequencing. Levins' measure and the Shannon–Wiener measure of niche breadth were calculated using family‐level identifications and Morisita's measure of niche overlap was calculated using operational taxonomic units (OTUs). Gut contents confirm both D. carolina and M. bivittatus as generalists and C. viridifasciata as a specialist on grasses. For M. femurrubrum, a high niche breadth was observed and species of grasses were identified in the gut as well as forbs. Niche overlap values did not follow predicted patterns, however, the low values suggest low competition between these species. 相似文献
24.
25.
Zhaoqiang Wang Yichen Ding Sandro Satta Mehrdad Roustaei Peng Fei Tzung K. Hsiai 《PLoS computational biology》2021,17(7)
Biomechanical forces intimately contribute to cardiac morphogenesis. However, volumetric imaging to investigate the cardiac mechanics with high temporal and spatial resolution remains an imaging challenge. We hereby integrated light-field microscopy (LFM) with light-sheet fluorescence microscopy (LSFM), coupled with a retrospective gating method, to simultaneously access myocardial contraction and intracardiac blood flow at 200 volumes per second. While LSFM allows for the reconstruction of the myocardial function, LFM enables instantaneous acquisition of the intracardiac blood cells traversing across the valves. We further adopted deformable image registration to quantify the ventricular wall displacement and particle tracking velocimetry to monitor intracardiac blood flow. The integration of LFM and LSFM enabled the time-dependent tracking of the individual blood cells and the differential rates of segmental wall displacement during a cardiac cycle. Taken together, we demonstrated a hybrid system, coupled with our image analysis pipeline, to simultaneously capture the myocardial wall motion with intracardiac blood flow during cardiac development. 相似文献
26.
Morteza Yousefzadi Mozafar Sharifi Mehrdad Behmanesh Alireza Ghasempour Elisabeth Moyano Javier Palazon 《Biotechnology letters》2010,32(11):1739-1743
Treatment of Linum album cell cultures with 10 μM salicylic acid (SA) for 3 days improved podophyllotoxin (PTOX) production up to 333 μg/g dry weight
(DW): over three times that of the control cultures. qPCR analyses showed that in SA-treated cells, the expression of the
genes coding for phenylalanine ammonia-lyase (PAL), cinnamoyl-CoA reductase (CCR) and cinnamyl-alcohol dehydrogenase (CAD), all involved in the first steps of PTOX biosynthesis, also increased reaching a peak 8–12 h after the treatment. Expression
of the pinoresinol-lariciresinol reductase gene (PLR), which is involved in one of the last biosynthetic steps, was not affected by SA. The selective action of SA on these genes
can be applied to control the biotechnological production of this anticancer agent. 相似文献
27.
The present study was designed to evaluate the effects of parenteral iron on red blood cell parameters, performance, and health
in dairy Holstein calves. Twenty neonatal calves were equally divided at random into two groups, one of which served as controls.
Care was taken to ensure homogeneity of sex, age, and general health status of the animals. The controls received a normal
diet and water ad libitum, while the study animals were injected with 1 g iron as Fe-dextran 2 days after birth. A daily record
was kept of the calves’ weight and growth parameters. At periods of 24–48 h after birth and at 14, 28, and 42 days of age,
jugular blood was drawn from all the experimental and control animals to measure the packed cell volume, red blood count,
hemoglobin, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and iron levels. At the start of the experiments,
there were no significant differences between these parameters between the two study groups (p > 0.05). With time, significant differences were seen between most of the values measured (p < 0.05) except for the mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and iron level. Significant
differences were seen for total weight gain and mean daily weight gain, which were higher in the iron-supplemented group (p < 0.05). 相似文献
28.
Cristián Tapia Sergio Molina Alvaro Diaz Lilian Abugoch Mario Diaz-Dosque Fernando Valenzuela Mehrdad Yazdani-Pedram 《AAPS PharmSciTech》2010,11(3):1294-1305
The effect of chitosan as internal or external coating on the mesalamine (5-ASA) release from calcium alginate microparticles (CaAl) was studied, and a delayed release of 5-ASA system intended for colonic drug delivery was developed. The external chitosan coating was developed by immersion of wetted CaAl in chitosan solution and the internal coating by mixing 5-ASA with chitosan solution and drying before the preparation of CaAl. Both systems were coated with Acryl-EZE® using combined fluid bed coating and immersion procedure. The results showed that in phosphate medium (pH 7.5), chitosan as 5-ASA coating promotes a quick erosion process accelerating drug release, but chitosan as external coating (CaAlCS) does not increase the T 50 value compared with the microparticles without chitosan (CaAl). Chitosan as internal or external coating was not effective to avoid the quick 5-ASA release in acidic medium (pH 1.2). The presence of β-glucosidase enzymes increases significantly the 5-ASA release for CaAl, while no effect was observed with chitosan as internal or external coating. Fourier transform infrared spectroscopy, thermogravimetric analysis, and X-ray data revealed that 5-ASA did not form a solid solution but was dispersed in the microparticles. The Acryl-EZE® coating of microparticles was effective because all the formulations showed a low release, less than 15%, of 5-ASA in acid medium at pH 1.2. Significant differences in the percentage of 5-ASA released between formulations were observed in phosphate buffer at pH 6.0. In phosphate buffer at pH 7.2, all the formulations released 100% of 5-ASA. 相似文献
29.
Yousefi Fatemeh Najafi Hadi Behmanesh Mehrdad Soltani Bahram M. 《Molecular biology reports》2022,49(5):3377-3387
Molecular Biology Reports - Aberrant activation of the Wnt signaling pathway is observed in most colorectal cancers (CRC). OCC-1D is a splice variant of OCC-1 gene which is considered as a long... 相似文献
30.
Salari Sepide Ghorbanpour Atefeh Marefati Narges Baluchnejadmojarad Tourandokht Roghani Mehrdad 《Molecular biology reports》2022,49(9):8429-8438
Molecular Biology Reports - Sepsis-associated acute kidney injury (AKI) accompanies a higher mortality in intensive care patients. High-dose lipopolysaccharides (LPS) as an endotoxin is usually... 相似文献