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111.
112.
Angelia D. Lockett Mary Beth Brown Nieves Santos-Falcon Natalia I. Rush Houssam Oueini Amber J. Oberle Esther Bolanis Miryam A. Fragoso Daniela N. Petrusca Karina A. Serban Kelly S. Schweitzer Robert G. Presson Jr. Michael Campos Irina Petrache 《PloS one》2014,9(4)
The homeostatic lung protective effects of alpha-1 antitrypsin (A1AT) may require the transport of circulating proteinase inhibitor across an intact lung endothelial barrier. We hypothesized that uninjured pulmonary endothelial cells transport A1AT to lung epithelial cells. Purified human A1AT was rapidly taken up by confluent primary rat pulmonary endothelial cell monolayers, was secreted extracellularly, both apically and basolaterally, and was taken up by adjacent rat lung epithelial cells co-cultured on polarized transwells. Similarly, polarized primary human lung epithelial cells took up basolaterally-, but not apically-supplied A1AT, followed by apical secretion. Evidence of A1AT transcytosis across lung microcirculation was confirmed in vivo by two-photon intravital microscopy in mice. Time-lapse confocal microscopy indicated that A1AT co-localized with Golgi in the endothelium whilst inhibition of the classical secretory pathway with tunicamycin significantly increased intracellular retention of A1AT. However, inhibition of Golgi secretion promoted non-classical A1AT secretion, associated with microparticle release. Polymerized A1AT or A1AT supplied to endothelial cells exposed to soluble cigarette smoke extract had decreased transcytosis. These results suggest previously unappreciated pathways of A1AT bidirectional uptake and secretion from lung endothelial cells towards the alveolar epithelium and airspaces. A1AT trafficking may determine its functional bioavailablity in the lung, which could be impaired in individuals exposed to smoking or in those with A1AT deficiency. 相似文献
113.
The reinstatement of biodiversity and ecological processes must be the major goal in restoration projects, which requires the establishment of biological interactions in addition to native plant population recovery. Therefore, we assessed the flower visitors of five tree species in a restored area of Semideciduous Seasonal Forest, in Ribeir?o Preto, SP, Brazil. The specimens were collected using entomological net on flowers of Acacia polyphylla, Aegiphila sellowianna, Croton floribundus, Croton urucurana and Schinus terebinthifolius from October 2007 to September 2008. A total of 139 insect species belonging to five orders were collected. Hymenoptera was the most diverse order collected. From a total of 37 families, Vespidae (15 species), Cabronidae (12), Apidae (10), Halictidae (10), Syrphidae (12), Tachinidae (6) and Hesperidae (7) were the richest ones. Schinus terebinthifolius flowers presented the most abundant and diverse insect visitors (60), suggesting it is an important attractive species to the fauna in restoration programs. Our data suggest that mutualistic interactions between some of these plants and their flower-visiting insects may be in a reinstatement process, and will support the design and monitoring of future restoration efforts. 相似文献
114.
Fragoso JM Vallejo M Alvarez-León E Delgadillo H Peña-Duque MA Cardoso-Saldaña G Posadas-Romero C Martínez-Ríos MA Vargas-Alarcón G 《Cytokine》2011,55(1):29-33
Inflammation plays an important role in the pathogenesis of atherosclerosis and acute coronary syndromes (ACS). Interleukin-10 (IL-10) is a potent anti-inflammatory cytokine that mediates the inflammatory process. The objective of the present study was to evaluate the role of IL-10 gene polymorphisms as susceptibility markers for ACS in Mexican patients. IL-10 promoter polymorphisms (positions -1082, -819, and -592) were analyzed by 5' exonuclease TaqMan genotyping assays in 389 ACS patients and 302 healthy controls. ACS patients showed increased frequencies of IL-10-592 C allele and CC genotype when compared to healthy controls (pC=0.0006, OR=1.48 and pC=0.022, OR=1.56, respectively), whereas the frequencies of the A allele and AA genotype were decreased in patients (pC=0.0006, OR=0.68 and pC=0.006, OR=0.57, respectively). When the distribution of IL-10-592 genotypes was analyzed separately in women and men (patients and healthy controls), a different distribution of alleles and genotypes was observed only in the group of men. In this case, increased frequency of C allele (pC=0.004, OR=1.46) and decreased frequencies of A allele (pC=0.004, OR=0.68) and AA genotype (pC=0.023, OR=0.56) were observed in the group of patients when compared to healthy controls. Multiple logistic analyses by gender showed that male individuals with IL-10-592CC+AC genotypes had 3.54-fold increased risk of developing ACS than individuals with AA genotype (p<0.001). The analysis of linkage disequilibrium showed one (ACC) increased haplotype in patients as compared to healthy controls. The results suggest that IL-10 gene polymorphisms could be involved in the risk of developing ACS in the Mexican population. 相似文献
115.
J Lailson-Brito R Cruz PR Dorneles L Andrade Ade F Azevedo AB Fragoso LG Vidal MB Costa TL Bisi R Almeida DP Carvalho WR Bastos O Malm 《PloS one》2012,7(7):e42162
Top marine predators present high mercury concentrations in their tissues as consequence of biomagnification of the most toxic form of this metal, methylmercury (MeHg). The present study concerns mercury accumulation by Guiana dolphins (Sotalia guianensis), highlighting the selenium-mediated methylmercury detoxification process. Liver samples from 19 dolphins incidentally captured within Guanabara Bay (Rio de Janeiro State, Brazil) from 1994 to 2006 were analyzed for total mercury (THg), methylmercury (MeHg), total organic mercury (TOrgHg) and selenium (Se). X-ray microanalyses were also performed. The specimens, including from fetuses to 30-year-old dolphins, comprising 8 females and 11 males, presented high THg (0.53-132 μg/g wet wt.) and Se concentrations (0.17-74.8 μg/g wet wt.). Correlations between THg, MeHg, TOrgHg and Se were verified with age (p<0.05), as well as a high and positive correlation was observed between molar concentrations of Hg and Se (p<0.05). Negative correlations were observed between THg and the percentage of MeHg contribution to THg (p<0.05), which represents a consequence of the selenium-mediated methylmercury detoxification process. Accumulation of Se-Hg amorphous crystals in Kupffer Cells was demonstrated through ultra-structural analysis, which shows that Guiana dolphin is capable of carrying out the demethylation process via mercury selenide formation. 相似文献
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117.
In Colombia, like most Neotropical countries, faunistic studies on flower flies have been occasional and most of them have been primarily focused on taxonomy. Colombia is the second-most species-rich country in flower fly diversity in the Neotropics after Brazil, and has one of the highest numbers of species per unit area (2.49 per 10,000?km2), based on a review of literature and national collections. Including new data presented here, a total of 47 genera and 300 species are recorded in Colombia. The genera Scaeva Fabricius and Lycastrirhyncha Bigot, as well as 101 species are recorded here for the first time. The altitudinal range and the distribution of the flower fly genera in Colombia are presented. A preliminary comparison of the fauna of Colombia with that of other Neotropical countries is given. A historical perspective is also provided in order to illustrate how Colombian Syrphidae knowledge has progressed over the last 168?years. Information presented here will be useful for ongoing and future biodiversity research as well as conservation projects on Syrphidae in the Neotropical region. 相似文献
118.
Ecological impacts of feral pigs in the Hawaiian Islands 总被引:1,自引:0,他引:1
Sérgio L. G. Nogueira-Filho Selene S. C. Nogueira José M. V. Fragoso 《Biodiversity and Conservation》2009,18(14):3677-3683
The foraging habits of exotic ungulate species can directly and indirectly affect native plant and animal distribution and
abundance patterns. Most of the studies on feral pig interactions with other biota in the Hawaiian Islands have been published
as difficult to access reports to governmental and nongovernmental organizations, graduate student theses, and a few in peer
reviewed journals. In this paper we discuss the origins of pig introductions to Hawaii, their feralization process, population
expansion, and interactions with native and non-native biota. We also consider the environmental effects triggered by pigs
on local ecosystems and biotic communities. Feral pig activities can reduce the abundance of native plant species, enhance
conditions for the establishment of invasive non-indigenous plants, and perhaps indirectly negatively impact native forest
bird species. Pig foraging and traveling patterns may also lead to physical alteration of ecosystems by increasing soil erosion
that may lead to watershed degradation. However, much remains to be learned about the strength and significance of aforementioned
interactions and their long-term effects on Hawaiian biota and ecosystems due to some confounding events. Elucidating the
dynamics and long-term ecological effects generated by pigs is a crucial step towards increasing our understanding of and
more effectively managing biotic interactions. 相似文献
119.
Catarina Addobbati Jordão Cavalcanti Jaqueline de Azevêdo Silva Will de Barros Pita Tiago Degani Veit Odirlei Andre Monticielo Ricardo Machado Xavier João Carlos Tavares Brenol Cleiton Viegas Brenol Thiago Sotero Fragoso Alexandre Domingues Barbosa Ângela Luiza Branco Pinto Duarte Renê Donizeti Ribeiro Oliveira Paulo Louzada-Júnior Eduardo Antônio Donadi Sergio Crovella José Artur Bogo Chies Paula Sandrin-Garcia 《Molecular biology reports》2016,43(1):41-51
120.