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71.
OBJECTIVE: To perform a minimally invasive procedure for atrial fibrillation without cardiopulmonary bypass, it is necessary to create transmural lesions on the beating heart. Although bipolar radiofrequency clamps can isolate the pulmonary veins, they have difficulty in performing any other left atrial lesions, particularly those of the traditional Cox-Maze procedure. This study examined the performance of an internally cooled, bipolar radiofrequency device designed for such an application. METHODS: Eleven domestic pigs underwent median sternotomy. Five animals had eight atrial lesions created with the radiofrequency device at times of 20, 30, 40, and 50 seconds. In six other pigs, the device was compared with another technology that has been used clinically for epicardial, beating heart ablation, the Guidant Flex 4 microwave device. The tissue was stained with 2,3,5-triphenyl-tetrazoluim chloride, and the lesions were sectioned at 5-mm intervals. Lesion width, depth, and transmurality were evaluated. RESULTS: The radiofrequency device had a linear dose-response relationship. Lesions were wider and deeper with increasing ablation times. A total of 40%, 45%, 60%, and 67% of lesions were transmural at times of 20, 30, 40, and 50 seconds, respectively. Ninety-one percent of lesions in tissue up to 4-mm thick were transmural after 50 seconds. However, performance in thicker tissue was poor. Lesions created by the device were deeper and more likely to be transmural than the Flex 4. CONCLUSIONS: This internally cooled, bipolar radiofrequency device can reliably create transmural lesions on tissue up to 4-mm thick and performs better than a microwave device. 相似文献
72.
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
73.
Francesco Patti Manuela De Stefano Luigi Lavorgna Silvia Messina Clara Grazia Chisari Domenico Ippolito Roberta Lanzillo Veria Vacchiano Sabrina Realmuto Paola Valentino Gabriella Coniglio Maria Buccafusca Damiano Paolicelli Alessandro D’Ambrosio Patrizia Montella Vincenzo Brescia Morra Giovanni Savettieri Bruno Alfano Antonio Gallo Isabella Simone Rosa Viterbo Mario Zappia Simona Bonavita Gioacchino Tedeschi 《PloS one》2015,10(3)
Background
Magnetic Resonance Imaging (MRI) techniques provided evidences into the understanding of cognitive impairment (CIm) in Multiple Sclerosis (MS).Objectives
To investigate the role of white matter (WM) and gray matter (GM) in predicting long-term CIm in a cohort of MS patients.Methods
303 out of 597 patients participating in a previous multicenter clinical-MRI study were enrolled (49.4% were lost at follow-up). The following MRI parameters, expressed as fraction (f) of intracranial volume, were evaluated: cerebrospinal fluid (CSF-f), WM-f, GM-f and abnormal WM (AWM-f), a measure of lesion load. Nine years later, cognitive status was assessed in 241 patients using the Symbol Digit Modalities Test (SDMT), the Semantically Related Word List Test (SRWL), the Modified Card Sorting Test (MCST), and the Paced Auditory Serial Addition Test (PASAT). In particular, being SRWL a memory test, both immediate recall and delayed recall were evaluated. MCST scoring was calculated based on the number of categories, number of perseverative and non-perseverative errors.Results
AWM-f was predictive of an impaired performance 9 years ahead in SDMT (OR 1.49, CI 1.12–1.97 p = 0.006), PASAT (OR 1.43, CI 1.14–1.80 p = 0.002), SRWL-immediate recall (OR 1.72 CI 1.35–2.20 p<0.001), SRWL-delayed recall (OR 1.61 CI 1.28–2.03 p<0.001), MCST-category (OR 1.52, CI 1.2–1.9 p<0.001), MCST-perseverative error(OR 1.51 CI 1.2–1.9 p = 0.001), MCST-non perseverative error (OR 1.26 CI 1.02–1.55 p = 0.032).Conclusion
In our large MS cohort, focal WM damage appeared to be the most relevant predictor of the long-term cognitive outcome. 相似文献74.
Cinnamyl alcohol dehydrogenases in the mesocarp of ripening fruit of Prunus persica genotypes with different flesh characteristics: changes in activity and protein and transcript levels 下载免费PDF全文
75.
The Protective Effect of Apocynin on Cyclosporine A‐Induced Hypertension and Nephrotoxicity in Rats 下载免费PDF全文
76.
Pacemaker channels produce an instantaneous current. 总被引:8,自引:0,他引:8
Catherine Proenza Damiano Angoli Eugene Agranovich Vincenzo Macri Eric A Accili 《The Journal of biological chemistry》2002,277(7):5101-5109
Spontaneous rhythmic activity in mammalian heart and brain depends on pacemaker currents (I(h)), which are produced by hyperpolarization-activated cyclic nucleotide-gated (HCN) channels. Here, we report that the mouse HCN2 pacemaker channel isoform also produced a large instantaneous current (I(inst(HCN2))) in addition to the well characterized, slowly activating I(h). I(inst(HCN2)) was specific to expression of HCN2 on the plasma membrane and its amplitude was correlated with that of I(h). The two currents had similar reversal potentials, and both were modulated by changes in intracellular Cl(-) and cAMP. A mutation in the S4 domain of HCN2 (S306Q) decreased I(h) but did not alter I(inst(HCN2)), and instantaneous currents in cells expressing either wild type HCN2 or mutant S306Q channels were insensitive to block by Cs(+). Co-expression of HCN2 with the accessory subunit, MiRP1, decreased I(h) and increased I(inst(HCN2)), suggesting a mechanism for modulation of both currents in vivo. These data suggest that expression of HCN channels may be accompanied by a background conductance in native tissues and are consistent with at least two open states of HCN channels: I(inst(HCN2)) is produced by a Cs(+)-open state; hyperpolarization produces an additional Cs(+)-sensitive open state, which results in I(h). 相似文献
77.
The effects of chemical modifications of the Na+-H+ antiport in Escherichia coli have been analyzed by studying the resulting variations of the energy-dependent, downhill Na+ efflux from membrane vesicles. The histidyl reagent diethylpyrocarbonate (EtO)2C2O3 prevents the activation of the Na+ efflux mechanism by delta microH+ or its components. Inactivation of the antiporter by (EtO)2C2O3 is completely reversed by hydroxylamine. The data suggest that histidine residues are involved in the molecular mechanism of the Na+-H+ antiport. In contrast, no conclusive evidence suggesting participation of carboxylic, tyrosine or sulfhydryl residues in the Na+-H+ exchange reaction has been obtained. 相似文献
78.
Alessandra Gagliardi Adriano Martinoli Damiano Preatoni Luc A. Wauters Guido Tosi 《Hydrobiologia》2007,583(1):213-222
The winter diet of great crested grebe (Podiceps cristatus) was studied in the major lakes of Insubria region, N Italy, in 2000–2003 by analysing stomach and oesophagus contents of
birds found dead. Winter diet of cormorant (Phalacrocorax carbo) was studied using pellet analysis. Diet was expressed in terms of numerical abundance, frequency and biomass of prey. A
detailed methodology is described of how to prepare a reference collection of otoliths, pharyngeal bones and chewing pads
(key-elements), essential for species-specific identification of fish remains in stomachs and pellets, and to estimate ingested
fish biomass. Correlations between mass (mg) of key-elements and mass of corresponding fish were significant, and exponential
regression models were used to calculate biomass of each single prey item directly from the mass of its key-elements. Advantages
of this method are compared with the more traditional two step approach in which size of elements is used to estimate fish
length, followed by calculating fresh mass from fish length. Cyprinids formed the largest part of the diet for both predators.
Great crested grebes selected small prey, feeding mainly on bleak (Alburnus alburnus alborella), while diet composition of cormorants varied significantly in relation to prey availability.
Handling editor: K. Martens 相似文献
79.
Isabel M.G. Padilla Agnieszka Golis Adele Gentile Carmine Damiano Ralph Scorza 《Plant Cell, Tissue and Organ Culture》2006,84(3):309-314
To determine the optimum conditions for Agrobacterium-mediated gene transfer, peach explants including cotyledons, embryonic axes and hypocotyl slices from non-germinated seeds
and epicotyl internode slices from germinating seeds were exposed to Agrobacterium-mediated transformation treatments. The GUS (uidA) marker gene was tested using two different A. tumefaciens strains, three plasmids and four promoters [CaMV35s, (Aocs)3AmasPmas (“super-promoter”), mas-CaMV35s, and CAB]. GFP was tested with six A.␣tumefaciens strains, one plasmid (pLC101) and the doubleCaMV35s (dCaMV35s) promoter. The CaMV35s promoter produced more GUS expression
than the CAB promoter. A. tumefaciens strains EHA105 and LBA4404 harboring the same plasmid (pBIN19) differed in their effects on GUS expression suggesting an
interaction between A. tumefaciens strain and plasmid. A combination of A. tumefaciens EHA105, plasmid pBIN19 and the CaMV35s promoter produced the highest rates of transformation in peach epicotyl internodes
(56.8%), cotyledons (52.7%), leaves (20%), and embryonic axes (46.7%) as evaluated by the percentage of explants expressing
GUS 14 days after co-cultivation. GFP expression under the control of the dCaMV35s promoter was highest for internode explants
but only reached levels of 18–19%. When GFP-containing plasmid pCL101 was combined with each of five A. tumefaciens strains the highest levels of transformation were 20–21% (internode and cotyledons, respectively). When nine peach genotypes
were co-cultivated with A. tumefaciens strain EHA105 and GFP-containing plasmid pCL101 the highest levels of transformation were 26–28% (cotyledons and internodes,
respectively). While GFP represents a potentially useful transformation marker that allows the non-destructive evaluation
of transformation, rates of GFP transformation under the conditions of this study were low. It will be necessary to optimize
expression of this marker gene in peach. 相似文献
80.
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