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排序方式: 共有421条查询结果,搜索用时 16 毫秒
101.
Julieta Reppetti Alejandra Reca E. Abril Seyahian Yollyseth Medina Nora Martínez Natalia Szpilbarg Alicia E. Damiano 《Journal of cellular physiology》2020,235(4):3382-3392
Caveolae constitute membrane domains critical for the organization and synchronization of different signaling molecules related to numerous cell processes such as cell migration, invasion, and differentiation. Caveolin-1 (Cav-1) is the main integral membrane protein of these domains. Recently, it was found that a normal expression of aquaporin-3 (AQP3) is required for extravillous trophoblast (EVT) cell migration. Our aim was to investigate the role of caveolae in the migration, invasion, and endovascular differentiation of human EVT cells during placentation and its interaction with AQP3. EVT cells (Swan 71 cell line) were cultured in complete Dulbecco's modified Eagle's medium–nutrient mixture F12 and treated with 5 mM methyl-β-cyclodextrin (MβCD) to disrupt caveolae. We found that after MβCD treatment, Cav-1 protein was undetectable. In this condition, the ability of the cells to migrate was significantly decreased compared with the control cells, while no differences were observed in the number of invading cells and the metalloproteinases activity between control and MβCD-treated cells. Surprisingly, the disruption of caveolae significantly enhanced EVT endovascular differentiation. On the contrary, the silencing of AQP3, negatively affected tube-like formation. The theoretical analysis of the primary sequence of AQP3 protein revealed a putative Cav-1-binding site. In addition, immunoprecipitation and double immunofluorescence assays showed that AQP3 colocalized with Cav-1. These results showed that during placentation an intact caveola in EVT cells may be necessary for AQP3 and Cav-1 interaction and any perturbations might result in serious pregnancy disorders. 相似文献
102.
Andrew RJ Mitchell Philip Roberts Jonas Eichhöfer Jonathan Timperley Oliver JM Ormerod 《Cardiovascular ultrasound》2004,2(1):1-4
Percutaneous coronary intervention can be associated with distal embolization of thrombotic material causing myocardial necrosis and infarction. We discuss the role of intravascular imaging to guide the use of a distal protection device by describing the outcome of a young woman presenting with non-ST elevation myocardial infarction. Coronary angiography demonstrated an isolated minor stenosis in the proximal left anterior descending coronary artery with slight haziness beyond the lesion. Intravascular ultrasound confirmed an extensive thrombus overlying a bulky atherosclerotic plaque. A distal filter wire was therefore successfully used to reduce the risk of distal embolization. The use of intravascular ultrasound in patients presenting with acute coronary syndrome may reveal large thrombi that are difficult to image using conventional angiographic techniques. Intravascular ultrasound can therefore be used as a tool to select lesions requiring distal protection. 相似文献
103.
Maria Dolores Arias Padrò Andrea Frattarelli Alessandra Sgueglia Emiliano Condello Carmine Damiano Emilia Caboni 《Plant Cell, Tissue and Organ Culture》2012,108(1):167-172
Shoot apices of in vitro-grown plantlets of white mulberry, Morus alba L. cv Florio, were cryopreserved using either encapsulation-dehydration or vitrification. For encapsulation-dehydration,
alginate beads containing apices were dehydrated for 1, 3, 5 or 7 days in a liquid medium containing various sucrose concentrations
(0.5, 0.75, 1.0 or 1.25 M). Bead desiccation was performed using silica gel for either 0, 4, 6, 8, 9 or 14 h. For vitrification,
apices were directly immersed for either 5, 15, 30 or 60 min in a vitrification solution (PVS2). Following encapsulation-dehydration,
treatment of alginate beads with 0.75 M sucrose was more effective in promoting re-growth of explants after immersion in liquid
nitrogen than in the presence of 0.5 M sucrose for either 1 or 3 days. Re-growth of explants was also observed following vitrification
and this reached 47% with increasing duration of the PVS2 treatment from 5 to 30 min. Overall, the highest frequency of explant
re-growth was obtained when explants were subjected to encapsulation-dehydration in the presence of 0.75 M along with a 3 day
sucrose dehydration pre-treatment and followed by desiccation for 9 h in silica gel. 相似文献
104.
Adriano Martinoli Damiano Preatoni Valeria Galanti Paola Codipietro Morris Kilewo Carlos A. R. Fernandes Luc A. Wauters Guido Tosi 《Biodiversity and Conservation》2006,15(5):1729-1744
The carnivore community of Arusha National Park, Tanzania, was monitored using live trapping and diurnal and nocturnal visual
counts and recording of tracks and signs along line transects. Nine carnivore species were recorded. Hyena (Crocuta crocuta), the most common large species, leopard (Panthera pardus) and African civet (Civettictis civetta) were detected along line transects, while the smaller species were counted and/or captured. Mungos mungo, Galerella sanguinea, and Genetta maculata were the most prevalent at transect counts, while G. sanguinea, Bdeogale crassicauda, and G. maculata were most frequently captured. Ichneumia albicauda and Ictonyx striatus were captured at only a single site. Carnivores selected natural habitat types, multilayered forest, open shrubs and herbaceous
savannah, and were absent, or tended to avoid disturbed (man-made) habitats. Species of which sufficient data were gathered
seemed to behave as habitat generalists (C. crocuta, G. sanguinea, G. maculata, M. mungo and I. striatus). The need for more detailed studies on small carnivore ecology and the importance of smaller protected areas for their conservation
are discussed. 相似文献
105.
Lucas Armand Wauters Goedele Verbeylen Damiano Preatoni Adriano Martinoli Erik Matthysen 《Population Ecology》2010,52(4):527-536
Animal dispersal and subsequent settlement is a key process in the life history of many organisms, when individuals use demographic
and environmental cues to target post-dispersal habitats where fitness will be highest. To investigate the hypothesis that
environmental disturbance (habitat fragmentation) may alter these cues, we compared dispersal patterns of 60 red squirrels
(Sciurus vulgaris) in three study sites that differ in habitat composition and fragmentation. We determined dispersal distances, pre- and post-dispersal
habitat types and survival using a combination of capture–mark–recapture, radio-tracking and genetic parentage assignment.
Most (75%) squirrels emigrated from the natal home range with mean dispersal distance of 1,014 ± 925 m (range 51–4,118 m).
There were no sex-related differences in dispersal patterns and no differences in average dispersal distance, and the proportion
of dispersers did not differ between sites. In one of the sites, dispersers settled in patches where density was lower than
in the natal patch. In the least fragmented site, 90% of animals settled in the natal habitat type (habitat cuing) against
44–54% in the more strongly fragmented sites. Overall, more squirrels settled in the natal habitat type than expected based
on habitat availability, but this was mainly due to individuals remaining within the natal wood. In the highly fragmented
landscape, habitat cuing among emigrants did not occur more frequently than expected. We concluded that increased habitat
fragmentation seemed to reduce reliable cues for habitat choice, but that dispersing squirrels settled in patches with lower
densities of same-sex animals than at the natal home range or patch, independent of degree of fragmentation. 相似文献
106.
107.
D'Elia D Catalano D Licciulli F Turi A Tripoli G Porcelli D Saccone C Caggese C 《Mitochondrion》2006,6(5):252-257
The oxidative phosphorylation (OXPHOS) is the primary energy-producing process of all aerobic organisms and the only cellular function under the dual control of both the mitochondrial and the nuclear genomes. Functional characterization and evolutionary study of the OXPHOS system is of great importance for the understanding of many as yet unclear aspects of nucleus-mitochondrion genomic co-evolution and co-regulation gene networks. The MitoDrome database is a web-based database which provides genomic annotations about nuclear genes of Drosophila melanogaster encoding for mitochondrial proteins. Recently, MitoDrome has included a new section annotating genomic information about OXPHOS genes in Drosophila pseudoobscura and Anopheles gambiae and their comparative analysis with their Drosophila melanogaster and human counterparts. The introduction of this new comparative annotation section into MitoDrome is expected to be a useful resource for both functional and structural genomics related to the OXPHOS system. 相似文献
108.
Niels H Chavannes Juanita HJ Vernooy Tjard RJ Schermer Jan A Jacobs Mieke A Dentener Chris van Weel Onno CP van Schayck Emiel FM Wouters 《BMC pulmonary medicine》2006,6(1):1-7
Background
Although both smoking and respiratory complaints are very common, tools to improve diagnostic accuracy are scarce in primary care. This study aimed to reveal what inflammatory patterns prevail in clinically established diagnosis groups, and what factors are associated with eosinophilia.Method
Induced sputum and blood plasma of 59 primary care patients with COPD (n = 17), asthma (n = 11), chronic bronchitis (CB, n = 14) and smokers with no respiratory complaints ('healthy smokers', n = 17) were collected, as well as lung function, smoking history and clinical work-up. Patterns of inflammatory markers per clinical diagnosis and factors associated with eosinophilia were analyzed by multiple regression analyses, the differences expressed in odds ratios (OR) with 95% confidence intervals.Results
Multivariately, COPD was significantly associated with raised plasma-LBP (OR 1.2 [1.04–1.37]) and sTNF-R55 in sputum (OR 1.01 [1.001–1.01]), while HS expressed significantly lowered plasma-LBP (OR 0.8 [0.72–0.95]). Asthma was characterized by higher sputum eosinophilic counts (OR 1.3 [1.05–1.54]), while CB showed a significantly higher proportion of sputum lymphocytic counts (OR 1.5 [1.12–1.9]). Sputum eosinophilia was significantly associated with reversibility after adjusting for smoking, lung function, age, gender and allergy.Conclusion
Patterns of inflammatory markers in a panel of blood plasma and sputum cells and mediators were discernable in clinical diagnosis groups of respiratory disease. COPD and so-called healthy smokers showed consistent opposite associations with plasma LBP, while chronic bronchitics showed relatively predominant lymphocytic inflammation compared to other diagnosis groups. Only sputum eosinophilia remained significantly associated with reversibility across the spectrum of respiratory disease in smokers with airway complaints. 相似文献109.
基因治疗是未来临床医学最具潜力的治疗方式,目前阻碍临床基因治疗发展的主要因素是缺乏安全和高效的基因载体,因此研究理想的非病毒转基因载体具有重要的意义.构建了由质粒DNA(D)-抗DNA抗体(A)-阳离子脂质体(C)组成的三元复合纳米基因载体(DAC),研究表明,三组分在磷酸缓冲液中可通过分子组装形成复合纳米胶束,DAC在细胞培养中表现出显著高效的基因表达,DAC在血管平滑肌细胞中的基因转染效率比不含抗DNA抗体的二元组合(DC)高4倍,比不含阳离子脂质体的二元组合(DA)约高11倍.激光共聚焦荧光显微观察证明,DAC细胞摄取量和DNA进入细胞核的量均明显高于对照组,而DC二元组合(不含抗DNA抗体)的DNA很少进入细胞核,细胞在DAC存在下生长正常.未发现细胞毒性.研究结果提示,DAC的作用机理主要是三元复合胶束中DNA的装载量比二元载体大得多,抗DNA抗体与阳离子脂质体的协同作用明显有利于DNA被细胞摄取和胞吞,从而提高了基因的转染和表达. 相似文献
110.
Giudetti AM Sabetta S di Summa R Leo M Damiano F Siculella L Gnoni GV 《Journal of lipid research》2003,44(11):2135-2141
The mitochondrial tricarboxylate carrier (TCC) plays an important role in lipogenesis being TCC-responsible for the efflux from the mitochondria to the cytosol of acetyl-CoA, the primer for fatty acid synthesis. In this study, we investigated the effects of two high-fat diets with different fatty acid composition on the hepatic TCC activity. Rats were fed for 3 weeks on a basal diet supplemented with 15% of either coconut oil (CO), abundant in medium-chain saturated fatty acids, or fish oil (FO), rich in n-3 polyunsaturated fatty acids. Mitochondrial fatty acid composition was differently influenced by the dietary treatments, while no appreciable change in phospholipid composition and cholesterol level was observed. Compared with CO, the TCC activity was markedly decreased in liver mitochondria from FO-fed rats; kinetic analysis of the carrier revealed a decrease of the Vmax, with no change of the Km. No difference in the Arrhenius plot between the two groups was observed. Interestingly, the carrier protein level and the corresponding mRNA abundance decreased following FO treatment. These data indicate that FO administration markedly decreased the TCC activity as compared with CO. This effect is most likely due to a reduced gene expression of the carrier protein. 相似文献