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71.
Loss of the serine/threonine kinase fused results in postnatal growth defects and lethality due to progressive hydrocephalus 总被引:3,自引:0,他引:3
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72.
Erinna F. Lee Grant Dewson Marco Evangelista Anne Pettikiriarachchi Grace J. Gold Haoran Zhu Peter M. Colman W. Douglas Fairlie 《The Journal of biological chemistry》2014,289(52):36001-36017
Bcl-2 homology 3 (BH3) domains are short sequence motifs that mediate nearly all protein-protein interactions between B cell lymphoma 2 (Bcl-2) family proteins in the intrinsic apoptotic cell death pathway. These sequences are found on both pro-survival and pro-apoptotic members, although their primary function is believed to be associated with induction of cell death. Here, we identify critical features of the BH3 domains of pro-survival proteins that distinguish them functionally from their pro-apoptotic counterparts. Biochemical and x-ray crystallographic studies demonstrate that these differences reduce the capacity of most pro-survival proteins to form high affinity “BH3-in-groove” complexes that are critical for cell death induction. Switching these residues for the corresponding residues in Bcl-2 homologous antagonist/killer (Bak) increases the binding affinity of isolated BH3 domains for pro-survival proteins; however, their exchange in the context of the parental protein causes rapid proteasomal degradation due to protein destabilization. This is supported by further x-ray crystallographic studies that capture elements of this destabilization in one pro-survival protein, Bcl-w. In pro-apoptotic Bak, we demonstrate that the corresponding distinguishing residues are important for its cell-killing capacity and antagonism by pro-survival proteins. 相似文献
73.
Martina Ardizzi Francesca Martini Maria Alessandra Umiltà Valentina Evangelista Roberto Ravera Vittorio Gallese 《PloS one》2015,10(10)
The development of the explicit recognition of facial expressions of emotions can be affected by childhood maltreatment experiences. A previous study demonstrated the existence of an explicit recognition bias for angry facial expressions among a population of adolescent Sierra Leonean street-boys exposed to high levels of maltreatment. In the present study, the recognition bias for angry facial expressions was investigated in a younger population of street-children and age-matched controls. Participants performed a forced-choice facial expressions recognition task. Recognition bias was measured as participants’ tendency to over-attribute anger label to other negative facial expressions. Participants’ heart rate was assessed and related to their behavioral performance, as index of their stress-related physiological responses. Results demonstrated the presence of a recognition bias for angry facial expressions among street-children, also pinpointing a similar, although significantly less pronounced, tendency among controls. Participants’ performance was controlled for age, cognitive and educational levels and for naming skills. None of these variables influenced the recognition bias for angry facial expressions. Differently, a significant effect of heart rate on participants’ tendency to use anger label was evidenced. Taken together, these results suggest that childhood exposure to maltreatment experiences amplifies children’s “pre-existing bias” for anger labeling in forced-choice emotion recognition task. Moreover, they strengthen the thesis according to which the recognition bias for angry facial expressions is a manifestation of a functional adaptive mechanism that tunes victim’s perceptive and attentive focus on salient environmental social stimuli. 相似文献
74.
Jean Pierre Schatzmann Peron Auriléia Aparecida de Brito Mayra Pelatti Wesley Nogueira Brand?o Luana Beatriz Vitoretti Flávia Regina Greiffo Elaine Cristina da Silveira Manuel Carneiro Oliveira-Junior Mariangela Maluf Lucila Evangelista Silvio Halpern Marcelo Gil Nisenbaum Paulo Perin Carlos Eduardo Czeresnia Niels Olsen Saraiva Camara Flávio Aimbire Rodolfo de Paula Vieira Mayana Zatz Ana Paula Ligeiro de Oliveira 《PloS one》2015,10(8)
Cigarette smoke-induced chronic obstructive pulmonary disease is a very debilitating disease, with a very high prevalence worldwide, which results in a expressive economic and social burden. Therefore, new therapeutic approaches to treat these patients are of unquestionable relevance. The use of mesenchymal stromal cells (MSCs) is an innovative and yet accessible approach for pulmonary acute and chronic diseases, mainly due to its important immunoregulatory, anti-fibrogenic, anti-apoptotic and pro-angiogenic. Besides, the use of adjuvant therapies, whose aim is to boost or synergize with their function should be tested. Low level laser (LLL) therapy is a relatively new and promising approach, with very low cost, no invasiveness and no side effects. Here, we aimed to study the effectiveness of human tube derived MSCs (htMSCs) cell therapy associated with a 30mW/3J—660 nm LLL irradiation in experimental cigarette smoke-induced chronic obstructive pulmonary disease. Thus, C57BL/6 mice were exposed to cigarette smoke for 75 days (twice a day) and all experiments were performed on day 76. Experimental groups receive htMSCS either intraperitoneally or intranasally and/or LLL irradiation either alone or in association. We show that co-therapy greatly reduces lung inflammation, lowering the cellular infiltrate and pro-inflammatory cytokine secretion (IL-1β, IL-6, TNF-α and KC), which were followed by decreased mucus production, collagen accumulation and tissue damage. These findings seemed to be secondary to the reduction of both NF-κB and NF-AT activation in lung tissues with a concomitant increase in IL-10. In summary, our data suggests that the concomitant use of MSCs + LLLT may be a promising therapeutic approach for lung inflammatory diseases as COPD. 相似文献
75.
Pollen grains of 15 taxa of the genus Chelonopsis (14 spp. and 1 variety) from China and Japan and 6 species of the closely related genera Bostrychanthera (1 species) and Gomphostemma (5 species) were examined by light and scanning electron microscopy. Of these, the pollen morphology of 18 taxa was studied for the first time. Pollen grains were found to be tricolpate with polar lengths of 20.8–30.0 μm and equatorial widths of 17.5–27.3 μm. The basic shape of the pollen in most taxa is subprolate or prolate-spheroidal, but spheroidal, subprolate-spheroidal, oblate-spheroidal, and prolate-subprolate grains are also found in some species. The surface is generally reticulate or suprareticulate in Chelonopsis and granulate in Bostrychanthera. In comparison with those of Chelonopsis and Bostrychanthera, the pollen grain surfaces of Gomphostemma are more diverse. In Chelonopsis, pollen is taxonomically useful at the sectional level, and some grains provide enough characters for species delimitation. The potential pollination ecology of cellular hairs on the anthers of Chelonopsis and Bostrychanthera is also briefly discussed. 相似文献
76.
Eduardo Soudah Paula Rudenick Maurizio Bordone Bart Bijnens David García-Dorado Arturo Evangelista 《Computer methods in biomechanics and biomedical engineering》2013,16(8):805-815
An aortic dissection (AD) is a serious condition defined by the splitting of the arterial wall, thus generating a secondary lumen [the false lumen (FL)]. Its management, treatment and follow-up are clinical challenges due to the progressive aortic dilatation and potentially severe complications during follow-up. It is well known that the direction and rate of dilatation of the artery wall depend on haemodynamic parameters such as the local velocity profiles, intra-luminal pressures and resultant wall stresses. These factors act on the FL and true lumen, triggering remodelling and clinical worsening. In this study, we aimed to validate a computational fluid dynamic (CFD) tool for the haemodynamic characterisation of chronic (type B) ADs. We validated the numerical results, for several dissection geometries, with experimental data obtained from a previous in vitro study performed on idealised dissected physical models. We found a good correlation between CFD simulations and experimental measurements as long as the tear size was large enough so that the effect of the wall compliance was negligible. 相似文献
77.
Antinori A Marcotullio S Ammassari A Andreoni M Angarano G Carosi G Cinque P d'Arminio Monforte A Di Perri G Ensoli B Ferrazzi E Galli M Mastroianni C Matteelli A Mazzotta F Moroni M Palù G Puoti M Puro V Rizzardini G Sagnelli E Suter F Vella S Lazzarin A;Italian HIV Guidelines Working Group 《The new microbiologica》2011,34(2):109-146
78.
Aerodynamic studies using physical models of fossil organisms can provide quantitative information about how performance of defined activities, such as gliding, depends on specific morphological features. Such analyses allow us to rule out hypotheses about the function of extinct organisms that are not physically plausible and to determine if and how specific morphological features and postures affect performance. The purpose of this article is to provide a practical guide for the design of dynamically scaled physical models to study the gliding of extinct animals using examples from our research on the theropod dinosaur, ?Microraptor gui, which had flight feathers on its hind limbs as well as on its forelimbs. Analysis of the aerodynamics of ?M. gui can shed light on the design of gliders with large surfaces posterior to the center of mass and provide functional information to evolutionary biologists trying to unravel the origins of flight in the dinosaurian ancestors and sister groups to birds. Measurements of lift, drag, side force, and moments in pitch, roll, and yaw on models in a wind tunnel can be used to calculate indices of gliding and parachuting performance, aerodynamic static stability, and control effectiveness in maneuvering. These indices permit the aerodynamic performance of bodies of different shape, size, stiffness, texture, and posture to be compared and thus can provide insights about the design of gliders, both biological and man-made. Our measurements of maximum lift-to-drag ratios of 2.5-3.1 for physical models of ?M. gui suggest that its gliding performance was similar to that of flying squirrels and that the various leg postures that might have been used by ?M. gui make little difference to that aspect of aerodynamic performance. We found that body orientation relative to the movement of air past the animal determines whether it is difficult or easy to maneuver. 相似文献
79.
80.
Deyze Alencar Soares Marilia Barros Oliveira Adriane Feijó Evangelista Emerson José Venancio Rosangela Vieira Andrade Maria Sueli Soares Felipe Silvana Petrofeza 《Memórias do Instituto Oswaldo Cruz》2013,108(6):808-811
Phospholipase is an important virulence factor for pathogenic fungi. In this
study, we demonstrate the following: (i) the Paracoccidioides
brasiliensis pld gene is preferentially expressed in mycelium
cells, (ii) the plb1 gene is mostly up-regulated by infection
after 6 h of co-infection of MH-S cells or during BALB/c mice
lung infection, (iii) during lung infection, plb1,
plc and pld gene expression are
significantly increased 6-48 h post-infection compared to 56 days after
infection, strongly suggesting that phospholipases play a role in the early
events of infection, but not during the chronic stages of pulmonary infection by
P. brasiliensis. 相似文献