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991.
992.
Tatiane Assone Fernando Vieira de Souza Karen Oliveira Gaester Luiz Augusto Marcondes Fonseca Olinda do Carmo Luiz Fernanda Malta Jo?o Renato Rebello Pinho Fernanda de Toledo Gon?alves Alberto Jose da Silva Duarte Augusto Cesar Penalva de Oliveira Jorge Casseb 《PLoS neglected tropical diseases》2014,8(9)
993.
Previous greenhouse gas (GHG) assessments for the shrub willow biomass crops (SWBC) production system lacked quantitative data on the soil CO2 efflux (Fc). This study quantifies the mean annual cumulative Fc, the C sequestration in the above- and belowground biomass, and the carbon balance of the production system. We utilized four SWBC fields, which have been in production for 5, 12, 14, and 19 years. Two treatments were applied: continuous production (CP)—shrub willows were harvested, and stools were allowed to regrow, and tear-out (TO) (crop removal)—shrub willows were harvested, and stools were sprayed with herbicide following spring, crushed, and mixed into the soil. Mean annual cumulative Fc were measured using dynamic closed chambers (LI-8100A and LI-8150). Across different age classes, the mean cumulative Fc ranged from 27.2 to 35.5 Mg CO2 ha?1 year?1 for CP and 26.5 to 29.3 Mg CO2 ha?1 year?1 for TO. The combined carbon (C) sequestration of the standing above- and belowground biomass, excluding stems, ranged from 50.6 to 94.8 Mg CO2 eqv. ha?1. In the CP treatment, the annual C sequestration in the fine roots and foliage offsets the annual cumulative Fc. Across different age classes, C balances ranged from ?21.5 to ?59.3 Mg CO2 ha?1 for CP and 26.5 to 29.3 Mg CO2 ha?1 for TO. The GHG potential of SWBC is about ?36.3 Mg CO2 eqv. ha?1 at the end of 19 years, suggesting that the SWBC system sequesters C until termination of the crop. 相似文献
994.
Lorenzo Mari Renato Casagrandi Enrico Bertuzzo Andrea Rinaldo Marino Gatto 《Theoretical Ecology》2014,7(4):351-365
The transmission of waterborne pathogens is a complex process that is heavily linked to the spatial characteristics of the underlying environmental matrix as well as to the temporal variability of the relevant hydroclimatological drivers. In this work, we propose a time-varying, spatially explicit network model for the dynamics of waterborne diseases. Applying Floquet theory, which allows to extend results of local stability analysis to periodic dynamical systems, we find conditions for pathogen invasion and establishment in systems characterized by fluctuating environmental forcing, thus extending to time-varying contexts the generalized reproduction numbers recently obtained for spatially explicit epidemiology of waterborne disease. We show that temporal variability may have multifaceted effects on the invasion threshold, as it can either favor pathogen invasion or make it less likely. Moreover, environmental fluctuations characterized by distinctive geographical signatures can produce diversified, highly nontrivial effects on pathogen invasion. Our study is complemented by numerical simulations, which show that pathogen establishment is neither necessary nor sufficient for large epidemic outbreaks to occur in time-varying environments. Finally, we show that our framework can be used to reliably characterize the early geography of epidemic outbreaks triggered by fluctuating environmental conditions. 相似文献
995.
Debora Monteiro Moretti Lalima Gagan Ahuja Rodrigo Dutra Nunes Cecília Oliveira Cudischevitch Carlos Renato Oliveira Daumas-Filho Priscilla Medeiros-Castro Guilherme Ventura-Martins Willy Jablonka Felipe Gazos-Lopes Raquel Senna Marcos Henrique Ferreira Sorgine Klaus Hartfelder Margareth Capurro Georgia Correa Atella Rafael Dias Mesquita Mário Alberto Cardoso Silva-Neto 《PloS one》2014,9(8)
Background
Protein Tyrosine Phosphatases (PTPs) are enzymes that catalyze phosphotyrosine dephosphorylation and modulate cell differentiation, growth and metabolism. In mammals, PTPs play a key role in the modulation of canonical pathways involved in metabolism and immunity. PTP1B is the prototype member of classical PTPs and a major target for treating human diseases, such as cancer, obesity and diabetes. These signaling enzymes are, hence, targets of a wide array of inhibitors. Anautogenous mosquitoes rely on blood meals to lay eggs and are vectors of the most prevalent human diseases. Identifying the mosquito ortholog of PTP1B and determining its involvement in egg production is, therefore, important in the search for a novel and crucial target for vector control.Methodology/Principal Findings
We conducted an analysis to identify the ortholog of mammalian PTP1B in the Aedes aegypti genome. We identified eight genes coding for classical PTPs. In silico structural and functional analyses of proteins coded by such genes revealed that four of these code for catalytically active enzymes. Among the four genes coding for active PTPs, AAEL001919 exhibits the greatest degree of homology with the mammalian PTP1B. Next, we evaluated the role of this enzyme in egg formation. Blood feeding largely affects AAEL001919 expression, especially in the fat body and ovaries. These tissues are critically involved in the synthesis and storage of vitellogenin, the major yolk protein. Including the classical PTP inhibitor sodium orthovanadate or the PTP substrate DiFMUP in the blood meal decreased vitellogenin synthesis and egg production. Similarly, silencing AAEL001919 using RNA interference (RNAi) assays resulted in 30% suppression of egg production.Conclusions/Significance
The data reported herein implicate, for the first time, a gene that codes for a classical PTP in mosquito egg formation. These findings raise the possibility that this class of enzymes may be used as novel targets to block egg formation in mosquitoes. 相似文献996.
997.
998.
Mychelle Morais-de-Jesus Renato Daltro-Oliveira Karine Miranda Pettersen Adriana Dantas-Duarte Luciana Di-Domizio Amaral Patrícia Cavalcanti-Ribeiro Carlos Teles Santos Maria Isabel Schinoni Liana R. Netto Lucas Araújo-de-Freitas Raymundo Paraná ?ngela Miranda-Scippa Karestan C. Koenen Lucas C. Quarantini 《PloS one》2014,9(10)
Objective
The purpose of this study was to evaluate whether individuals consider their HCV infection to be a potentially traumatic experience. Additionally, we investigated its association with Post-Traumatic Stress Disorder (PTSD) and the impact of PTSD diagnosis on health-related quality of life (HRQoL) in HCV infected subjects.Methods
We conducted a cross-sectional survey of 127 HCV-infected outpatients recruited at a University Hospital in Salvador, Brazil. All subjects answered an orally-administered questionnaire to gather clinical and socio-demographic data. We investigated traumatic experiences and the subject''s perception of the disease using the Trauma History Questionnaire. PTSD and other psychiatric diagnoses were assessed through the Mini International Neuropsychiatric Interview-Brazilian Version 5.0.0 (M.I.N.I. PLUS). HRQoL was assessed using Short-Form 36 (SF-36).Results
Approximately 38.6% of the patients considered hepatitis C to be a traumatic experience. Of these, 60.7% had a PTSD diagnosis. PTSD was associated with significant impairment in quality of life for individuals in seven SF-36 domains as shown bymultivariate analysis: Role-Physical (β: −24.85; 95% CI: −42.08; −7.61), Bodily Pain (β: −19.36; 95% CI: −31.28; −7.45), General Health (β: −20.79; 95% CI: −29.65; −11.92), Vitality (β: −11.92; 95% CI: −20.74; −3.1), Social Functioning (β: −34.73; 95% CI: −46.79; −22.68), Role-Emotional (β: −26.07; 95% CI: −44.61; −7.53), Mental Health (β: −17.46; 95% CI: −24.38; −10.54).Conclusion
HCV is frequently a traumatic experience and it is strongly associated with PTSD diagnosis. PTSD significantly impaired HRQoL. 相似文献999.
Daniele Saverino Giampaola Pesce Princey Antola Brunetta Porcelli Ignazio Brusca Danilo Villalta Marilina Tampoia Renato Tozzoli Elio Tonutti Maria Grazia Alessio Marcello Bagnasco Nicola Bizzaro 《PloS one》2014,9(11)
Primary biliary cirrhosis (PBC) is a chronic autoimmune cholestatic liver disease frequently characterized by anti-mitochondrial autoantibodies (AMA). A minority of patients are AMA-negative. Cytotoxic-T-Lymphocyte-Antigen-4 (CTLA-4) is a surface molecule expressed on activated T-cells delivering a critical negative immunoregulatory signal. A soluble form of CTLA-4 (sCTLA-4) has been detected at high concentrations in several autoimmune diseases, and its possible functional meaning has been suggested. We aimed to evaluate sCTLA-4 concentration in sera of patients with PBC and to correlate it to immunological abnormalities associated with the disease. Blood samples were collected from 82 PBC-patients diagnosed according to international criteria (44 AMA-positive/MIT3-positive and 38 AMA-negative-MIT3-negative), and 65 controls. sCTLA-4 levels were evaluated by ELISA and Western blot. Increased sCTLA-4 concentrations were found in all AMA-positive PBC-patients, but in none of the AMA-negative ones, nor in normal controls or in controls with unrelated liver diseases. sCTLA-4 presence was associated with autoantibodies against MIT3, but not with nuclear autoantibodies (sp100, gp210). This is the first study to demonstrate that levels of sCTLA-4 are elevated in sera of PBC patients. However, they are clearly restricted to patients with AMA positivity, suggesting an immunological difference with respect to AMA-negative ones. 相似文献
1000.
The lipopolysaccharides (LPS) of Shigella flexneri are important for virulence and their O antigen (Oag) polysaccharide chains affect IcsA (VirG)-mediated actin-based motility (ABM) within mammalian cells. S. flexneri 2a 2457T has smooth LPS whose Oag chains have two modal lengths (short (S)-type and very long (VL)-type), and has IcsA predominantly located at one pole on its cell surface. A S. flexneri 2457T wzz(SF) mutant (RMA696) has VL-type Oag but not S-type Oag chains, less IcsA detectable by immunofluorescence on its cell surface, reduced virulence and defective ABM. Introduction of a plasmid encoding IcsA into S. flexneri wzz(SF) showed that multicopy icsA could suppress the virulence defects (Sereny reaction, HeLa cell monolayer plaquing, and F-actin comet tail formation) caused by the wzz(SF) mutation suggesting that the VL-type Oag chains were masking IcsA and limiting the amount available to initiate ABM. 相似文献