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991.
In Type 2 Diabetes Mellitus Glycated Albumin Alters Macrophage Gene Expression Impairing ABCA1‐Mediated Cholesterol Efflux
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Adriana Machado‐Lima Rodrigo T. Iborra Raphael S. Pinto Gabriela Castilho Camila H. Sartori Erika R. Oliveira Ligia S. Okuda Edna R. Nakandakare Daniel Giannella‐Neto Ubiratan F. Machado Maria Lucia C. Corrêa‐Giannella Pietro Traldi Simona Porcu Marco Roverso Annunziata Lapolla Marisa Passarelli 《Journal of cellular physiology》2015,230(6):1250-1257
992.
Fabio S. Lima Georgios Oikonomou Svetlana F. Lima Marcela L. S. Bicalho Erika K. Ganda Jose C. de Oliveira Filho Gustavo Lorenzo Plamen Trojacanec Rodrigo C. Bicalho 《Applied and environmental microbiology》2015,81(4):1327-1337
Microbes present in the rumen of dairy cows are essential for degradation of cellulosic and nonstructural carbohydrates of plant origin. The prepartum and postpartum diets of high-producing dairy cows are substantially different, but in what ways the rumen microbiome changes in response and how those changes may influence production traits are not well elucidated. Here, we sequenced the 16S and 18S rRNA genes using the MiSeq platform to characterize the prepartum and postpartum rumen fluid microbiomes in 115 high-producing dairy cows, including both primiparous and multiparous animals. Discriminant analysis identified differences between the microbiomes of prepartum and postpartum samples and between primiparous and multiparous cows. 18S rRNA sequencing revealed an overwhelming dominance of the protozoan class Litostomatea, with over 90% of the eukaryotic microbial population belonging to that group. Additionally, fungi were relatively more prevalent and Litostomatea relatively less prevalent in prepartum samples than in postpartum ones. The core rumen microbiome (common to all samples) consisted of 64 bacterial taxa, of which members of the genus Prevotella were the most prevalent. The Chao1 richness index was greater for prepartum multiparous cows than for postpartum multiparous cows. Multivariable models identified bacterial taxa associated with increased or reduced milk production, and general linear models revealed that a metagenomically based prediction of productivity is highly associated with production of actual milk and milk components. In conclusion, the structure of the rumen fluid microbiome shifts between the prepartum and first-week postpartum periods, and its profile within the context of this study could be used to accurately predict production traits. 相似文献
993.
Chemotype of tansy (Tanacetum vulgare L.) determines aphid genotype and its associated predator system
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Klára Benedek János Bálint Rozália Veronika Salamon Erika Kovács Beáta Ábrahám Csaba Fazakas Hugh D. Loxdale Adalbert Balog 《Biological journal of the Linnean Society. Linnean Society of London》2015,114(3):709-719
Field assessments and genetic analyses on tansy aphid, Metopeurum fuscoviride Stroyan were made aiming to investigate whether a specialist aphid species and its associated predator density differ between chemotypes of the plant host, tansy, and whether the essential oil composition of the plant host determines the genetic differences observed between colonies of M. fuscoviride inhabiting these different chemotypes. Tansy plants were defined after volatile extractions as Camphor Pure and Borneol Pure, respectively, with hybrid chemotypes defined as Camphor Hybrid, Borneol Hybrid, and Thujone Hybrid, respectively. Ladybird beetles, Coccinella septempunctata (L.), clearly dominated Pure Camphor plants, whereas significantly higher numbers of the nursery web spider, Pisaura mirabilis (Clerck), were detected on Borneol Pure and Borneol Hybrid plants. Genetic analyses using five polymorphic microsatellite markers revealed that higher genetic similarity existed between M. fuscoviride aphids from Borneol Pure and Borneol Hybrid plants and between Camphor Pure and Camphor Hybrid plants, respectively, whereas a lower level of genetic similarity was seen between these aphids from Thujone Hybrid plants. Accordingly, it is possible that host plant‐adapted species can create much context‐dependency in the nature and strength of predation effects, which may in turn alter costs and benefits of host plant chemical differentiations, or even the prey genotype variations. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 114 , 709–719. 相似文献
994.
995.
An increased knee abduction angle during jump-landing has been identified as a risk factor for anterior cruciate ligament injuries. Activation of the hip abductors may decrease the knee abduction angle during jump-landing. The purpose of this study was to examine the effects of a resistance band on the internal hip abduction moment and gluteus medius activation during the pre-landing (100 ms before initial contact) and early-landing (100 ms after initial contact) phases of a jump–landing–jump task. Thirteen male and 15 female recreational athletes (age: 21.1±2.4 yr; mass: 73.8±14.6 kg; height: 1.76±0.1 m) participated in the study. Subjects performed jump–landing–jump tasks with or without a resistance band applied to their lower shanks. During the with-band condition, subjects were instructed to maintain their movement patterns as performing the jump-landing task without a resistance band. Lower extremity kinematics, kinetics, and gluteus medius electromyography (EMG) were collected. Applying the band increased the average hip abduction moment during pre-landing (p<0.001, Cohen?s d (d)=2.8) and early-landing (p<0.001, d=1.5), and the average gluteus medius EMG during pre-landing (p<0.001, d=1.0) and early-landing (p=0.003, d=0.55). Applying the band decreased the initial hip flexion angle (p=0.028, d=0.25), initial hip abduction angle (p<0.001, d=0.91), maximum knee flexion angle (p=0.046, d=0.17), and jump height (p=0.004, d=0.16). Applying a resistance band provides a potential strategy to train the strength and muscle activation for the gluteus medius during jump-landing. Additional instructions and feedback regarding hip abduction, hip flexion, and knee flexion may be required to minimize negative changes to other kinematic variables. 相似文献
996.
Erika L. Gallo Kathleen A. Lohse Christopher M. Ferlin Thomas Meixner Paul D. Brooks 《Biogeochemistry》2014,121(1):189-207
Rapid increases in human population and land transformation in arid and semi-arid regions are altering water, carbon (C) and nitrogen (N) cycles, yet little is known about how urban ephemeral stream channels in these regions affect biogeochemistry and trace gas fluxes. To address these knowledge gaps, we measured carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4) before and after soil wetting in 16 ephemeral stream channels that vary in soil texture and organic matter in Tucson, AZ. Fluxes of CO2 and N2O immediately following wetting were among the highest ever published (up to 1,588 mg C m?2 h?1 and 3,121 μg N m?2 h?1). Mean post-wetting CO2 and N2O fluxes were significantly higher in the loam and sandy loam channels (286 and 194 mg C m?2 h?1; 168 and 187 μg N m?2 h?1) than in the sand channels (45 mg C m?2 h?1 and 7 μg N m?2 h?1). Factor analyses show that the effect of soil moisture, soil C and soil N on trace gas fluxes varied with soil texture. In the coarser sandy sites, trace gas fluxes were primarily controlled by soil moisture via physical displacement of soil gases and by organic soil C and N limitations on biotic processes. In the finer sandy loam sites trace gas fluxes and N-processing were primarily limited by soil moisture, soil organic C and soil N resources. In the loam sites, finer soil texture and higher soil organic C and N enhance soil moisture retention allowing for more biologically favorable antecedent conditions. Variable redox states appeared to develop in the finer textured soils resulting in wide ranging trace gas flux rates following wetting. These findings indicate that urban ephemeral channels are biogeochemical hotspots that can have a profound impact on urban C and N biogeochemical cycling pathways and subsequently alter the quality of localized water resources. 相似文献
997.
Animal-assisted invention (AAI) in gaining attention as a therapeutic modality; however, the effect of it has not been well studied in the child welfare system. The purpose of this study was to examine the effects of AAI on stress indicators (as measured by salivary alpha-amylase (sAA), immunoglobulin A (IgA), and heart rate) in children undergoing forensic interviews for alleged sexual abuse. A repeated measures design was used in this study. Upon receiving signed, informed consents and assents, children were enrolled in the study. Children (n = 42), whose ages ranged from 5 to 14 years (M = 8.91, SD = 2.33), were assigned to either the intervention condition (n = 19; AAI during forensic interview) or the control condition (n = 23; standard practice forensic interview). Each child's parent/guardian completed a demographic form, and saliva samples and heart rate measures were obtained from each child before and after the forensic interview. Mixed linear models were tested, with the level of significance set at p ≤ 0.05. There was an interactive effect regarding the duration of the interview and the presence of the dog on sAA after the forensic interview (p = 0.047). There also was a significant interaction between age and length of interview (p = 0.01). Salivary immunoglobulin A tended to be lower (p = 0.055) when the therapy dog was present during the forensic interview. Results further indicated that the drop in heart rate was greater in longer interviews and with older children (p = 0.02) when the dog was present. Individuals working in child welfare systems can use the results of this study to advocate for the use of therapy dogs as a therapeutic intervention. More research is needed to further examine the relationships among AAI, salivary biomarkers, and stress responses in children to improve child welfare. 相似文献
998.
Roxanne S. Beltran Nissa Kreidler Dirk H. Van Vuren Scott A. Morrison Erika S. Zavaleta Kelly Newton Bernie R. Tershy Donald A. Croll 《Restoration Ecology》2014,22(6):790-797
Understanding how insular ecosystems recover or are restructured after the eradication of an invasive species is crucial in evaluating conservation success and prioritizing island conservation efforts. Globally, herbivores have been removed from 762 islands, most with limited active restoration actions following eradication. Few studies have documented the effects of invasive herbivore removal after multiple decades of passive recovery. Here we evaluate recovery of vegetation on Santa Cruz Island, California, after the removal of feral sheep (Ovis aries) in 1984. We repeat a study conducted in 1980, and examine vegetation changes 28 years after the eradication. Before eradication, grazed areas were characterized by reduced plant cover, high exposure of bare ground, and erosion. After 28 years of passive recovery, transect data showed a 23% increase in woody overstory, whereas analysis of photographs from landscapes photographed pre‐ and post‐eradication showed a 26% increase in woody vegetation. Whole island vegetation maps similarly showed a transition from grass/bare ground (74.3% of cover) to woody plants (77.2% of cover), indicating the transition away from predominantly exotic annual grassland toward a community similar to the overstory of coastal scrubland but with an understory dominated by non‐native annual grasses. We estimate that replacement of grasses/bare ground by native woody vegetation has led to 70 and 17% increases in the stored carbon and nitrogen pools on the island, respectively. Our results demonstrate that these island ecosystems can experience significant recovery of native floral communities without intensive post‐eradication restoration, and results of recovery may take decades to be realized. 相似文献
999.
Erika Berenguer Joice Ferreira Toby Alan Gardner Luiz Eduardo Oliveira Cruz Aragão Plínio Barbosa De Camargo Carlos Eduardo Cerri Mariana Durigan Raimundo Cosme De Oliveira Junior Ima Célia Guimarães Vieira Jos Barlow 《Global Change Biology》2014,20(12):3713-3726
Tropical rainforests store enormous amounts of carbon, the protection of which represents a vital component of efforts to mitigate global climate change. Currently, tropical forest conservation, science, policies, and climate mitigation actions focus predominantly on reducing carbon emissions from deforestation alone. However, every year vast areas of the humid tropics are disturbed by selective logging, understory fires, and habitat fragmentation. There is an urgent need to understand the effect of such disturbances on carbon stocks, and how stocks in disturbed forests compare to those found in undisturbed primary forests as well as in regenerating secondary forests. Here, we present the results of the largest field study to date on the impacts of human disturbances on above and belowground carbon stocks in tropical forests. Live vegetation, the largest carbon pool, was extremely sensitive to disturbance: forests that experienced both selective logging and understory fires stored, on average, 40% less aboveground carbon than undisturbed forests and were structurally similar to secondary forests. Edge effects also played an important role in explaining variability in aboveground carbon stocks of disturbed forests. Results indicate a potential rapid recovery of the dead wood and litter carbon pools, while soil stocks (0–30 cm) appeared to be resistant to the effects of logging and fire. Carbon loss and subsequent emissions due to human disturbances remain largely unaccounted for in greenhouse gas inventories, but by comparing our estimates of depleted carbon stocks in disturbed forests with Brazilian government assessments of the total forest area annually disturbed in the Amazon, we show that these emissions could represent up to 40% of the carbon loss from deforestation in the region. We conclude that conservation programs aiming to ensure the long‐term permanence of forest carbon stocks, such as REDD+, will remain limited in their success unless they effectively avoid degradation as well as deforestation. 相似文献
1000.