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961.
Carlos Passos Federico Reyes Bettina Tassino Gil G. Rosenthal Andrés González 《Ethology : formerly Zeitschrift fur Tierpsychologie》2013,119(10):891-897
Chemical communication is an important mediator of social interactions in fish, including mate recognition, mate choice and intrasexual competition. We used a simultaneous‐choice design to test the response of adult females of the annual killifish, Austrolebias reicherti, towards male‐conditioned water, both crude and fractionated into its polar and non‐polar components. Females preferred male‐conditioned water when tested both against control water and female‐conditioned water. The polar and non‐polar fractions of the male‐conditioned water were not significantly attractive, although a tendency was observed towards the non‐polar fraction. Our study shows that annual fish respond to the chemical cues of potential mates. The chemical channel is likely to be particularly important in the muddy ephemeral ponds in which they occur. 相似文献
962.
Recent advances in brain energy metabolism support the notion that glycogen in astrocytes is necessary for the clearance of neuronally-released K+ from the extracellular space. However, how the multiple metabolic pathways involved in K+-induced increase in glycogen turnover are regulated is only partly understood. Here we summarize the current knowledge about the mechanisms that control glycogen metabolism during enhanced K+ uptake. We also describe the action of the ubiquitous Na+/K+ ATPase for both ion transport and intracellular signaling cascades, and emphasize its importance in understanding the complex relation between glycogenolysis and K+ uptake. 相似文献
963.
Daniela Calzia Stefano Barabino Paolo Bianchini Greta Garbarino Michele Oneto Federico Caicci Alberto Diaspro Carlo Tacchetti Lucia Manni Simona Candiani Silvia Ravera Alessandro Morelli Carlo Enrico Traverso Isabella Panfoli 《Biology of the cell / under the auspices of the European Cell Biology Organization》2013,105(8):345-358
964.
965.
Averna M Stifanese R De Tullio R Minicucci L Cresta F Palena S Salamino F Pontremoli S Melloni E 《Biochimica et biophysica acta》2011,1812(12):1649-1657
We are here reporting that in peripheral blood mononuclear cells (PBMC) of patients homozygous for F508del-CFTR the calpain-calpastatin system undergoes a profound alteration. In fact, calpain basal activity, almost undetectable in control PBMC, becomes measurable at a significant extent in cells from cystic fibrosis (CF) patients, also due to a 40-60% decrease in both calpastatin protein and inhibitory activity. Constitutive protease activation in CF patients' cells induces a large accumulation of the mutated cystic fibrosis transmembrane conductance regulator (CFTR) in the 100kD+70kD split forms as well as a degradation of proteins associated to the CFTR complex. Specifically, the scaffolding protein Na(+)/H(+) exchanger 3 regulatory factor-1 (NHERF-1) is converted in two distinct fragments showing masses of 35kD and 20kD, being however the latter form the most represented one, thereby indicating that in CF-PBMC the CFTR complex undergoes a large disorganization. In conclusion, our observations are providing new information on the role of calpain in the regulation of plasma membrane ion conductance and provide additional evidence on the transition of this protease activity from a physiological to a pathological function. 相似文献
966.
Marta López-Sánchez Mariana Mu?oz-Esquerre Daniel Huertas José Gonzalez-Costello Jesús Ribas Federico Manresa Jordi Dorca Salud Santos 《PloS one》2013,8(6)
Background
A subclinical left ventricle diastolic dysfunction (LVDD) has been described in patients with chronic obstructive pulmonary disease (COPD).Objectives
To evaluate the prevalence of LVDD in stable severe COPD patients, to analyze its relationship with exercise capacity and to look for its possible causes (lung hyperinflation, ventricular interdependence or inflammatory mechanisms).Methods
We evaluated 106 consecutive outpatients with severe COPD (FEV1 between 30–50%). Thirty-three (31%) were excluded because of previous heart disease. A pulmonary function test, a 6-minute walking test (6MWT), a Doppler echocardiography test, including diastolic dysfunction parameters, and an analysis of arterial blood gases, NT-proBNP and serum inflammatory markers (CRP, leucocytes), were performed in all patients.Results
The prevalence of LVDD in severe stable COPD patients was 90% (80% type I, n=57, and 10% type II, n=7). A significant association between a lower E/A ratio (higher LVDD type I) and a lower exercise tolerance (6-minute walked distance (6MWD)) was found (r=0.29, p<0.05). The fully adjusted multivariable linear regression model demonstrated that a lower E/A ratio, a DLCO in the quartile 4th and a higher tobacco consumption were associated with a lower 6MWD (76, 57 and 0.7 metres, respectively, p<0.05). A significant correlation between E/A ratio and PaO2 was observed (r=0.26, p<0.05), but not with static lung hyperinflation, inflammation or right ventricle overload parameters.Conclusion
In stable severe COPD patients, the prevalence of LVDD is high and this condition might contribute in their lower exercise tolerance. Hypoxemia could have a concomitant role in their pathogenesis. 相似文献967.
Federico?Pozzo Michele?Dal BoEmail author Nadia?Peragine Riccardo?Bomben Antonella?Zucchetto Francesca?Maria?Rossi Massimo?Degan Davide?Rossi Annalisa?Chiarenza Alberto?Grossi Francesco?Di Raimondo Francesco?Zaja Gabriele?Pozzato Paola?Secchiero Gianluca?Gaidano Giovanni?Del Poeta Giorgio?Zauli Robin?Foà Anna?Guarini Valter?Gattei 《Journal of hematology & oncology》2013,6(1):83
968.
Federico De Martino Jan Zimmermann Lars Muckli Kamil Ugurbil Essa Yacoub Rainer Goebel 《PloS one》2013,8(3)
Ultra high fields (7T and above) allow functional imaging with high contrast-to-noise ratios and improved spatial resolution. This, along with improved hardware and imaging techniques, allow investigating columnar and laminar functional responses. Using gradient-echo (GE) (T2* weighted) based sequences, layer specific responses have been recorded from human (and animal) primary visual areas. However, their increased sensitivity to large surface veins potentially clouds detecting and interpreting layer specific responses. Conversely, spin-echo (SE) (T2 weighted) sequences are less sensitive to large veins and have been used to map cortical columns in humans. T2 weighted 3D GRASE with inner volume selection provides high isotropic resolution over extended volumes, overcoming some of the many technical limitations of conventional 2D SE-EPI, whereby making layer specific investigations feasible. Further, the demonstration of columnar level specificity with 3D GRASE, despite contributions from both stimulated echoes and conventional T2 contrast, has made it an attractive alternative over 2D SE-EPI. Here, we assess the spatial specificity of cortical depth dependent 3D GRASE functional responses in human V1 and hMT by comparing it to GE responses. In doing so we demonstrate that 3D GRASE is less sensitive to contributions from large veins in superficial layers, while showing increased specificity (functional tuning) throughout the cortex compared to GE. 相似文献
969.
Tenascin C (TNC) is an extracellular matrix protein that is upregulated during development as well as tissue remodeling. TNC is comprised of multiple independent folding domains, including 15 fibronectin type III-like (TNCIII) domains. The fifth TNCIII domain (TNCIII5) has previously been shown to bind heparin. Our group has shown that the heparin-binding fibronectin type III domains of fibronectin (FNIII), specifically FNIII12–14, possess affinity towards a large number of growth factors. Here, we show that TNCIII5 binds growth factors promiscuously and with high affinity. We produced recombinant fragments of TNC representing the first five TNCIII repeats (TNCIII1–5), as well as subdomains, including TNCIII5, to study interactions with various growth factors. Multiple growth factors of the platelet-derived growth factor (PDGF) family, the fibroblast growth factor (FGF) family, the transforming growth factor beta (TGF-β) superfamily, the insulin-like growth factor binding proteins (IGF-BPs), and neurotrophins were found to bind with high affinity to this region of TNC, specifically to TNCIII5. Surface plasmon resonance was performed to analyze the kinetics of binding of TNCIII1–5 with TGF-β1, PDGF-BB, NT-3, and FGF-2. The promiscuous yet high affinity of TNC for a wide array of growth factors, mediated mainly by TNCIII5, may play a role in multiple physiological and pathological processes involving TNC. 相似文献