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991.
Simone Guglielmetti Ivan Zanoni Silvia Balzaretti Matteo Miriani Valentina Taverniti Ivano De Noni Ilaria Presti Milda Stuknyte Alessio Scarafoni Stefania Arioli Stefania Iametti Francesco Bonomi Diego Mora Matti Karp Francesca Granucci 《Applied and environmental microbiology》2014,80(17):5170-5177
Bifidobacteria are Gram-positive inhabitants of the human gastrointestinal tract that have evolved close interaction with their host and especially with the host''s immune system. The molecular mechanisms underlying such interactions, however, are largely unidentified. In this study, we investigated the immunomodulatory potential of Bifidobacterium bifidum MIMBb75, a bacterium of human intestinal origin commercially used as a probiotic. Particularly, we focused our attention on TgaA, a protein expressed on the outer surface of MIMBb75''s cells and homologous to other known bacterial immunoactive proteins. TgaA is a peptidoglycan lytic enzyme containing two active domains: lytic murein transglycosylase (LT) and cysteine- and histidine-dependent amidohydrolase/peptidase (CHAP). We ran immunological experiments stimulating dendritic cells (DCs) with the B. bifidum MIMBb75 and TgaA, with the result that both the bacterium and the protein activated DCs and triggered interleukin-2 (IL-2) production. In addition, we observed that the heterologous expression of TgaA in Bifidobacterium longum transferred to the bacterium the ability to induce IL-2. Subsequently, immunological experiments performed using two purified recombinant proteins corresponding to the single domains LT and CHAP demonstrated that the CHAP domain is the immune-reactive region of TgaA. Finally, we also showed that TgaA-dependent activation of DCs requires the protein CD14, marginally involves TRIF, and is independent of Toll-like receptor 4 (TLR4) and MyD88. In conclusion, our study suggests that the bacterial CHAP domain is a novel microbe-associated molecular pattern actively participating in the cross talk mechanisms between bifidobacteria and the host''s immune system. 相似文献
992.
Angelo Gismondi Sara Caldarola Gaia Lisi Giada Juli Lidia Chellini Valentina Iadevaia Christopher G. Proud Fabrizio Loreni 《Nucleic acids research》2014,42(20):12668-12680
The synthesis of adequate amounts of ribosomes is an essential task for the cell. It is therefore not surprising that regulatory circuits exist to organize the synthesis of ribosomal components. It has been shown that defect in ribosome biogenesis (ribosomal stress) induces apoptosis or cell cycle arrest through activation of the tumor suppressor p53. This mechanism is thought to be implicated in the pathophysiology of a group of genetic diseases such as Diamond Blackfan Anemia which are called ribosomopathies. We have identified an additional response to ribosomal stress that includes the activation of eukaryotic translation elongation factor 2 kinase with a consequent inhibition of translation elongation. This leads to a translational reprogramming in the cell that involves the structurally defined group of messengers called terminal oligopyrimidine (TOP) mRNAs which encode ribosomal proteins and translation factors. In fact, while general protein synthesis is decreased by the impairment of elongation, TOP mRNAs are recruited on polysomes causing a relative increase in the synthesis of TOP mRNA-encoded proteins compared to other proteins. Therefore, in response to ribosomal stress, there is a change in the translation pattern of the cell which may help restore a sufficient level of ribosomes. 相似文献
993.
Valentina Castro-Huertas James P. Pitts Juanita Rodriguez Cecilia?Waichert Fernando Fernández 《ZooKeys》2014,(443):35-44
New records of genera and species of spider wasps (Hymenoptera: Pompilidae) from Colombia are provided. Agenioideus, Cryptocheilus, Evagetes, Mystacagenia, and Xerochares are newly recorded genera from Colombia. Nineteen species are first recorded from Colombia: Aimatocare
vitrea (Fox); Ageniella
azteca (Cameron); Ageniella
curtipinus (Cameron); Ageniella
fallax (Arlé); Ageniella
hirsuta Banks; Ageniella
pilifrons (Cameron); Ageniella
pretiosa Banks; Ageniella
sanguinolenta (Smith); Ageniella
zeteki (Banks); Agenioideus
birkmanni (Banks); Aporus (Aporus) cuzco Evans; Aporus (Cosmiaporus) diverticulus (Fox); Aporus (Notoplaniceps) canescens Smith; Euplaniceps
exilis (Banks); Euplaniceps
herbertii (Fox); Irenangelus
clarus Evans; Mystacagenia
bellula Evans; Phanochilus
nobilitatus (Smith) and Xerochares
expulsus Schulz. The following species and genera have their occurence ranges expanded for South America: Ageniella
azteca (Cameron); Ageniella
zeteki (Banks); Agenioideus
birkmanni (Banks); and Xerochares
expulsus Schulz; Cryptocheilus Panzer; and Xerochares Evans. 相似文献
994.
Valentina S. A. Mella Christine E. Cooper Stephen J. J. F. Davies 《Austral ecology》2014,39(1):115-121
Predation risk influences foraging decisions and time allocation of prey species, and may result in habitat shifts from potentially dangerous to safer areas. We examined a wild population of western grey kangaroos (Macropus fuliginosus) to test the efficacy of predator faecal odour in influencing time allocated to different behaviours and inducing changes in habitat use. Kangaroos were exposed to fresh faeces of a historical predator, the dingo (Canis lupus dingo), a recently introduced predator, the red fox (Vulpes vulpes), a herbivore (horse, Equus caballus) and an unscented control simultaneously. Kangaroos did not increase vigilance in predator‐scented areas. However, they investigated odour sources by approaching and sniffing; more time was spent investigating fox odour than control odours. Kangaroos then exhibited a clear anti‐predator response to predator odours, modifying their space use by rapidly escaping, then avoiding fox and dingo odour sources. Our results demonstrate that wild western grey kangaroos show behavioural responses to predator faeces, investigating then avoiding these olfactory cues of potential predation risk, rather than increasing general vigilance. This study contributes to our understanding of the impact of introduced mammalian predators on marsupial prey and demonstrates that a native Australian marsupial can recognize and respond to the odour of potential predators, including one that has been recently introduced. 相似文献
995.
Olivier Jolliet Rolf Frischknecht Jane Bare Anne-Marie Boulay Cecile Bulle Peter Fantke Shabbir Gheewala Michael Hauschild Norihiro Itsubo Manuele Margni Thomas E. McKone Llorenç Mila y Canals Leo Postuma Valentina Prado-Lopez Brad Ridoutt Guido Sonnemann Ralph K. Rosenbaum Tom Seager Jaap Struijs Rosalie van Zelm Bruce Vigon Annie Weisbrod 《The International Journal of Life Cycle Assessment》2014,19(4):962-967
996.
Daniele Cespi Fabrizio Passarini Luca Ciacci Ivano Vassura Valentina Castellani Elena Collina Andrea Piazzalunga Luciano Morselli 《The International Journal of Life Cycle Assessment》2014,19(1):89-99
Purpose
Biomass provides an attractive solution for residential heating systems based on renewable fuels, even though biomass-based domestic heating systems are recognized as significant particulate matter emitters; thus, a life cycle assessment (LCA) approach was used in the study to compare two different appliances: a wood stove and a pellet stove, both modeled according to the best available technologies definition.Methods
System boundaries of each scenario refer to a cradle-to-grave approach, including production, use and disposal of the heating appliance, as well as the preparation of biomass feedstock. The assessment of environmental impacts was performed assuming 1 MJ of thermal energy as the reference flow, considering the categories of particulate matter formation, human toxicity, climate change, and fossil fuel depletion, according to the ReCiPe 1.07 method. Finally, the comparison was extended to certain innovative heating systems in order to qualitatively evaluate potential improvements in residential heating performances.Results and discussion
The results show that the wood stove reaches the highest scores in the categories of particulate matter formation and negative effects for human toxicity, as a consequence of the stove’s lower combustion efficiency, which would lead to a preference for the pellet stove. However, when climate change affecting human health and the ecosystem, and fossil depletion are considered, the choice appears more uncertain due to the energy consumption from the pelletizing step. Alternative technologies (e.g., solar panels in combination with a gas boiler) show better scores related to fine particles emission reduction, even if a worsening in other categories is observed. The results were validated by a sensitivity analysis.Conclusions
The study suggests that a LCA approach can support the choice of the best domestic heating system, helping to promote policy initiatives on a sound basis and to understand which are the main key levers to act for reducing the total environmental burdens of biomass-based heating appliances. 相似文献997.
Olivier Jolliet Rolf Frischknecht Jane Bare Anne-Marie Boulay Cecile Bulle Peter Fantke Shabbir Gheewala Michael Hauschild Norihiro Itsubo Manuele Margni Thomas E. McKone Llorenç Mila y Canals Leo Posthuma Valentina Prado-Lopez Brad Ridoutt Guido Sonnemann Ralph K. Rosenbaum Tom Seager Jaap Struijs Rosalie van Zelm Bruce Vigon Annie Weisbrod 《The International Journal of Life Cycle Assessment》2014,19(8):1566-1566
998.
Mehdi Menai Léopold Fezeu Hélène Charreire Emmanuelle Kesse-Guyot Mathilde Touvier Chantal Simon Christiane Weber Valentina A. Andreeva Serge Hercberg Jean-Michel Oppert 《PloS one》2014,9(9)
Changes in sedentary behaviours and physical activity according to retirement status need to be better defined. Retirement is a critical life period that may influence a number of health behaviours. We assessed past-year sedentary behaviours (television, computer and reading time during leisure, occupational and domestic sitting time, in h/week) and physical activity (leisure, occupational and domestic, in h/week) over 6 years (2000–2001 and 2007) using the Modifiable Activity Questionnaire in 2,841 participants (mean age: 57.3±5.0 y) of the SU.VI.MAX (Supplementation with Antioxidants and Minerals) cohort. Analyses were performed according to retirement status. Subjects retired in 2001 and 2007 (40%) were those who spent most time in sedentary behaviour and in physical activity during and outside leisure (p<0.001). Leisure-time sedentary behaviours increased in all subjects during follow-up (p<0.001), but subjects who retired between 2001 and 2007 (31%) were those who reported the greatest changes (+8.4±0.42 h/week for a combined indicator of leisure-time sedentary behaviour). They also had the greatest increase in time spent in leisure-time physical activity (+2.5±0.2 h/week). In subjects not retired 2001 and 2007 (29%), changes in time spent watching television were found positively associated with an increase in occupational physical activity (p = 0.04) and negatively associated with changes in leisure-time physical activity (p = 0.02). No consistent association between changes in sedentary behaviours and changes in physical activity was observed in subjects retired in 2001 and 2007. Public health interventions should target retiring age populations not only to encourage physical activity but also to limit sedentary behaviours. 相似文献
999.
Fabio Timeus Nicoletta Crescenzio Daniela Longoni Alessandra Doria Luiselda Foglia Sara Pagliano Stefano Vallero Valentina Decimi Johanna Svahn Giuseppe Palumbo Antonio Ruggiero Baldassarre Martire Marta Pillon Nicoletta Marra Carlo Dufour Ugo Ramenghi Paola Saracco 《PloS one》2014,9(7)
A multicentre study evaluating the presence of glycosil phosphatidyl-inositol (GPI)-negative populations was performed in 85 children with acquired aplastic anemia (AA). A GPI-negative population was observed in 41% of patients at diagnosis, 48% during immune-suppressive therapy (IST), and 45% in patients off-therapy. No association was found between the presence of a GPI-negative population at diagnosis and the response to IST. In addition, the response rate to IST did not differ between the patients who were GPI-positive at diagnosis and later developed GPI-negative populations and the 11 patients who remained GPI-positive. Two patients with a GPI-negative population >10%, and laboratory signs of hemolysis without hemoglobinuria were considered affected by paroxysmal nocturnal hemoglobinuria (PNH) secondary to AA; no thrombotic event was reported. Excluding the 2 patients with a GPI-negative population greater than 10%, we did not observe a significant correlation between LDH levels and GPI-negative population size. In this study monitoring for laboratory signs of hemolysis was sufficient to diagnose PNH in AA patients. The presence of minor GPI-negative populations at diagnosis in our series did not influence the therapeutic response. As occasionally the appearance of a GPI-negative population was observed at cyclosporine (CSA) tapering or AA relapse, a possible role of GPI-negative population monitoring during IST modulation may need further investigation. 相似文献
1000.
Valentina Pasqualetti Annamaria Altomare Michele Pier Luca Guarino Vittoria Locato Silvia Cocca Sara Cimini Rossella Palma Rossana Alloni Laura De Gara Michele Cicala 《PloS one》2014,9(5)