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81.
82.
Petros Moustardas Nikolaos P. E. Kadoglou Michalis Katsimpoulas Alkistis Kapelouzou Nikolaos Kostomitsopoulos Panayotis E. Karayannacos Alkiviadis Kostakis Christos D. Liapis 《PloS one》2014,9(9)
Aim
This study aimed to investigate the effects of combined atorvastatin and exercise treatment on the composition and stability of the atherosclerotic plaques in apolipoproteinE (apoE) knockout mice.Methods
Forty male, apoE−/− mice were fed a high-fat diet for 16 weeks. Thereafter, while maintained on high-fat diet, they were randomized into four (n = 10) groups for 8 additional weeks: Group CO: Control. Group AT: Atorvastatin treatment (10 mg/Kg/day). Group EX: Exercise-training on treadmill. Group AT+EX: Atorvastatin and simultaneous exercise training. At the study’s end, plasma cholesterol levels, lipids and triglycerides were measured, along with the circulating concentrations of matrix-metalloproteinases (MMP-2,3,8,9) and their inhibitors (TIMP-1,2,3). Plaque area and the relative concentrations of collagen, elastin, macrophages, smooth muscle cells, MMP-2,3,8,9 and TIMP-1,2,3 within plaques were determined. Lastly, MMP activity was assessed in the aortic arch.Results
All intervention groups showed a lower degree of lumen stenosis, with atheromatous plaques containing more collagen and elastin. AT+EX group had less stenosis and more elastin compared to single intervention groups. MMP-3,-8 -9 and macrophage intra-plaque levels were reduced in all intervention groups. EX group had increased TIMP-1 levels within the lesions, while TIMP-2 was decreased in all intervention groups. The blood levels of the above molecules increased during atherosclerosis development, but they did not change after the therapeutic interventions in accordance to their intra-plaque levels.Conclusion
The two therapeutic strategies act with synergy regarding the extent of the lesions and lumen stenosis. They stabilize the plaque, increasing its content in elastin and collagen, by influencing the MMP/TIMP equilibrium, which is mainly associated with the macrophage amount. While the increased MMP-2,-3,-8 -9, as well as TIMP-1 and TIMP-2 circulating levels are markers of atherosclerosis, they are not correlated with their corresponding concentrations within the lesions after the therapeutic interventions, and cannot serve as markers for the disease development/amelioration. 相似文献83.
Sylvaine Giakoumi Maria Sini Vasilis Gerovasileiou Tessa Mazor Jutta Beher Hugh P. Possingham Ameer Abdulla Melih Ertan ?inar Panagiotis Dendrinos Ali Cemal Gucu Alexandros A. Karamanlidis Petra Rodic Panayotis Panayotidis Ergun Taskin Andrej Jaklin Eleni Voultsiadou Chlo? Webster Argyro Zenetos Stelios Katsanevakis 《PloS one》2013,8(10)
Spatial priorities for the conservation of three key Mediterranean habitats, i.e. seagrass Posidonia oceanica meadows, coralligenous formations, and marine caves, were determined through a systematic planning approach. Available information on the distribution of these habitats across the entire Mediterranean Sea was compiled to produce basin-scale distribution maps. Conservation targets for each habitat type were set according to European Union guidelines. Surrogates were used to estimate the spatial variation of opportunity cost for commercial, non-commercial fishing, and aquaculture. Marxan conservation planning software was used to evaluate the comparative utility of two planning scenarios: (a) a whole-basin scenario, referring to selection of priority areas across the whole Mediterranean Sea, and (b) an ecoregional scenario, in which priority areas were selected within eight predefined ecoregions. Although both scenarios required approximately the same total area to be protected in order to achieve conservation targets, the opportunity cost differed between them. The whole-basin scenario yielded a lower opportunity cost, but the Alboran Sea ecoregion was not represented and priority areas were predominantly located in the Ionian, Aegean, and Adriatic Seas. In comparison, the ecoregional scenario resulted in a higher representation of ecoregions and a more even distribution of priority areas, albeit with a higher opportunity cost. We suggest that planning at the ecoregional level ensures better representativeness of the selected conservation features and adequate protection of species, functional, and genetic diversity across the basin. While there are several initiatives that identify priority areas in the Mediterranean Sea, our approach is novel as it combines three issues: (a) it is based on the distribution of habitats and not species, which was rarely the case in previous efforts, (b) it considers spatial variability of cost throughout this socioeconomically heterogeneous basin, and (c) it adopts ecoregions as the most appropriate level for large-scale planning. 相似文献
84.
Dimitrios E. Kouzoukas Guiying Li Maysaam Takapoo Thomas Moninger Ramesh C. Bhalla Nicholas J. Pantazis 《Journal of neurochemistry》2013,124(3):323-335
Alcohol is a potent neuroteratogen that can trigger neuronal death in the developing brain. However, the mechanism underlying this alcohol‐induced neuronal death is not fully understood. Utilizing primary cultures of cerebellar granule neurons (CGN), we tested the hypothesis that the alcohol‐induced increase in intracellular calcium [Ca2+]i causes the death of CGN. Alcohol induced a dose‐dependent (200–800 mg/dL) neuronal death within 24 h. Ratiometric Ca2+ imaging with Fura‐2 revealed that alcohol causes a rapid (1–2 min), dose‐dependent increase in [Ca2+]i, which persisted for the duration of the experiment (5 or 7 min). The alcohol‐induced increase in [Ca2+]i was observed in Ca2+‐free media, suggesting intracellular Ca2+ release. Pre‐treatment of CGN cultures with an inhibitor (2‐APB) of the inositol‐triphosphate receptor (IP3R), which regulates Ca2+ release from the endoplasmic reticulum (ER), blocked both the alcohol‐induced rise in [Ca2+]i and the neuronal death caused by alcohol. Similarly, pre‐treatment with BAPTA/AM, a Ca2+‐chelator, also inhibited the alcohol‐induced surge in [Ca2+]i and prevented neuronal death. In conclusion, alcohol disrupts [Ca2+]i homeostasis in CGN by releasing Ca2+ from intracellular stores, resulting in a sustained increase in [Ca2+]i. This sustained increase in [Ca2+]i may be a key determinant in the mechanism underlying alcohol‐induced neuronal death. 相似文献
85.
Christopher J. Pantazis Sarah Fisk Kerri Mills Barry S. Flinn Vladimir Shulaev Richard E. Veilleux Yinghui Dan 《Plant cell reports》2013,32(3):329-337
Key message
We developed an efficient Agrobacterium -mediated transformation method using an Ac/Ds transposon tagging construct for F. vesca and high throughput paromomycin spray assay to identify its transformants for strawberry functional genomics.Abstract
Genomic resources for Rosaceae species are now readily available, including the Fragaria vesca genome, EST sequences, markers, linkage maps, and physical maps. The Rosaceae Genomic Executive Committee has promoted strawberry as a translational genomics model due to its unique biological features and transformability for fruit trait improvement. Our overall research goal is to use functional genomic and metabolic approaches to pursue high throughput gene discovery in the diploid woodland strawberry. F. vesca offers several advantages of a fleshy fruit typical of most fruit crops, short life cycle (seed to seed in 12–16 weeks), small genome size (206 Mbb/C), small plant size, self-compatibility, and many seeds per plant. We have developed an efficient Agrobacterium tumefaciens-mediated strawberry transformation method using kanamycin selection, and high throughput paromomycin spray assay to efficiently identify transgenic strawberry plants. Using our kanamycin transformation method, we were able to produce up to 98 independent kanamycin resistant insertional mutant lines using a T-DNA construct carrying an Ac/Ds transposon Launchpad system from a single transformation experiment involving inoculation of 22 leaf explants of F. vesca accession 551572 within approx. 11 weeks (from inoculation to soil). Transgenic plants with 1–2 copies of a transgene were confirmed by Southern blot analysis. Using our paromomycin spray assay, transgenic F. vesca plants were rapidly identified within 10 days after spraying. 相似文献86.
A study of the sites of insulin binding in subcellular fractions of rat liver is reported. A method for the isolation of liver plasma membranes, which permits one to follow quantitatively the distribution of all the parameters of interest, was modified and applied to the study of the cellular topography of insulin binding. The insulin-binding capacity did not follow closely the enzyme marker (5′-nucleotidase) for plasma membranes when differential centrifugation schemes were used, and the divergence from this marker was more prominent when separations were performed on discontinuous sucrose gradients. A significant amount of insulin binding capacity was always present in fractions with higher density than those containing the majority of 5′-nucleotidase. Results of studies on linear sucrose gradients have disclosed in some of the purified membrane fractions small but consistent differences in density of the insulin binding, and plasma membrane particles. It is suggested that there may be several types of intracellular membranes to which insulin can bind besides the plasma membranes. 相似文献
87.
Summary The 7S nerve growth factor molecule, found in the mouse submandibular gland, is comprised of three distinct protein subunits named , and -NGF. In this paper, radioimmunoassays specific for each subunit were used to measure the concentrations of these subunits in homogenates of mouse submandibular gland. It was determined that there were excess concentrations of both the and subunits, more than enough to bind all of the -NGF in the gland to form 7S-NGF. The radioimmunoassay data was confirmed by gel filtration experiments. In the gel filtration experiments, the excess and subunits eluted at positions which would indicate that these excess subunits were free and not bound in the 7S-NGF complex. The identity of the excess and subunits was substantiated by ion exchange chromatography, isoelectric focusing polyacrylamide gels and immunoblotting experiments. In conclusion, there are considerable quantities of and subunits present in the submandibular gland which are not bound to -NGE The functional significance of these excess concentrations of the and subunits is not known. 相似文献
88.
89.
To determine if behavioral states are associated with unique spatial electrocorticographic (ECoG) patterns, we obtained recordings
with a microgrid electrode array applied to the cortical surface of a human subject. The array was constructed with the intent
of extracting maximal spatial information by optimizing interelectrode distances. A 34-year-old patient with intractable epilepsy
underwent intracranial ECoG monitoring after standard methods failed to reveal localization of seizures. During the 8-day
period of invasive recording, in addition to standard clinical electrodes a square 1 × 1 cm microgrid array with 64 electrodes
(1.25 mm separation) was placed on the right inferior temporal gyrus. Careful review of video recordings identified four extended
naturalistic behaviors: reading, conversing on the telephone, looking at photographs, and face-to-face interactions. ECoG
activity recorded with the microgrid that corresponded to these behaviors was collected and ECoG spatial patterns were analyzed.
During periods of ECoG selected for analysis, no electrographic seizures or epileptiform patterns were present. Moments of
maximal spatial variance are shown to cluster by behavior. Comparisons between conditions using a permutation test reveal
significantly different spatial patterns for each behavior. We conclude that ECoG recordings obtained on the cortical surface
with optimal high spatial frequency resolution reveal distinct local spatial patterns that reflect different behavioral states,
and we predict that similar patterns will be found in many if not most cortical areas on which a microgrid is placed. 相似文献
90.