953 research outputs found

    Análise in silico de proteínas quinases expressas em Coffea arabica.

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    Apesar da indiscutível importância agronômica do café, particularmente para o Brasil, esta cultura ainda é alvo de diferentes estresses que causam perda em sua produtividade. A resposta do cafeeiro aos diferentes sinais como patógenos e de condições ambientais adversas é ainda desconhecida. Com o objetivo de identificar proteínas quinases, o banco de seqüências expressas de Café (CAFEST) foi investigado. A análise do banco de dados CafEST revelou 479 seqüências identificadas como quinases que formaram um conjunto de 153 unigenes. As proteínas codificadas pelos segmentos expressos correspondem a diferentes e importantes categorias de quinases (MAPK, MAPKK, MAPKKK, receptores, etc). A análise filogenética mostrou a conservação das proteínas expressas no cafeeiro comparado a outras plantas e fungos. Os presentes resultados indicam que a resposta a estresses seja conservada em cafeeiro, provavelmente mediada pelos mecanismos de fosforilação em cascata. Além disso, apontam para o aprofundamento dos estudos destas vias como contribuição aos fenômenos relacionados à interação planta-patógeno

    Unveiling the Toxicity of Fine and Nano-Sized Airborne Particles Generated from Industrial Thermal Spraying Processes in Human Alveolar Epithelial Cells

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    High-energy industrial processes have been associated with particle release into workplace air that can adversely affect workers' health. The present study assessed the toxicity of incidental fine (PGFP) and nanoparticles (PGNP) emitted from atmospheric plasma (APS) and high-velocity oxy-fuel (HVOF) thermal spraying. Lactate dehydrogenase (LDH) release, 2-(4-nitrophenyl)-2H-5-tetrazolio]-1,3-benzene disulfonate (WST-1) metabolisation, intracellular reactive oxygen species (ROS) levels, cell cycle changes, histone H2AX phosphorylation (γ-H2AX) and DNA damage were evaluated in human alveolar epithelial cells at 24 h after exposure. Overall, HVOF particles were the most cytotoxic to human alveolar cells, with cell viability half-maximal inhibitory concentration (IC50) values of 20.18 μg/cm2 and 1.79 μg/cm2 for PGFP and PGNP, respectively. Only the highest tested concentration of APS-PGFP caused a slight decrease in cell viability. Particle uptake, cell cycle arrest at S + G2/M and γ-H2AX augmentation were observed after exposure to all tested particles. However, higher levels of γ-H2AX were found in cells exposed to APS-derived particles (~16%), while cells exposed to HVOF particles exhibited increased levels of oxidative damage (~17% tail intensity) and ROS (~184%). Accordingly, APS and HVOF particles seem to exert their genotoxic effects by different mechanisms, highlighting that the health risks of these process-generated particles at industrial settings should not be underestimated. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Funding text 1: transitória (Ref. DL-57/INSA-06/2018). Thanks are also due to FCT/MCTES for the financial support to EPIUnit and ITR (UIDB/04750/2020 and LA/P/0064/2020). Informed Consent Statement: Not applicable. Institutional Review Board Statement: Not applicable.; Funding text 2: Funding: This research was funded by the project CERASAFE with the support of ERA-NET SIINN (project id:16) and the Portuguese Foundation for Science and Technology (FCT; SIINN/0004/2014). This work was also supported by the project NanoBioBarriers (PTDC/MED-TOX/31162/2017), cofinanced by the Operational Program for Competitiveness and Internationalization (POCI) through European Regional Development Funds (FEDER/FNR) and FCT and the Spanish Ministry of Sci- ence and Innovation (projects PCIN-2015-173-C02-01 and CEX2018-000794-S-Severo Ochoa). M.J. Bessa (SFRH/BD/120646/2016) and F. Brandão (SFRH/BD/101060/2014) are recipients of FCT PhD scholarships under the framework of the Human Capital Operating Program (POCH) and European Union funding. The Doctoral Program in Biomedical Sciences of the ICBAS—University of Porto Int.J.Mol. Sci. 2022,of23fer, x FOR PEER REVIEWed additional funds. S. Fraga thanks FCT for funding through program DL 57/2016—Norm

    In Vitro Toxicity of Industrially Relevant Engineered Nanoparticles in Human Alveolar Epithelial Cells: Air-Liquid Interface versus Submerged Cultures

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    Diverse industries have already incorporated within their production processes engineered nanoparticles (ENP), increasing the potential risk of worker inhalation exposure. In vitro models have been widely used to investigate ENP toxicity. Air–liquid interface (ALI) cell cultures have been emerging as a valuable alternative to submerged cultures as they are more representative of the inhalation exposure to airborne nano-sized particles. We compared the in vitro toxicity of four ENP used as raw materials in the advanced ceramics sector in human alveolar epithelial-like cells cultured under submerged or ALI conditions. Submerged cultures were exposed to ENP liquid suspensions or to aerosolised ENP at ALI. Toxicity was assessed by determining LDH release, WST-1 metabolisation and DNA damage. Overall, cells were more sensitive to ENP cytotoxic effects when cultured and exposed under ALI. No significant cytotoxicity was observed after 24 h exposure to ENP liquid suspensions, although aerosolised ENP clearly affected cell viability and LDH release. In general, all ENP increased primary DNA damage regardless of the exposure mode, where an increase in DNA strand-breaks was only detected under submerged conditions. Our data show that at relevant occupational concentrations, the selected ENP exert mild toxicity to alveolar epithelial cells and exposure at ALI might be the most suitable choice when assessing ENP toxicity in respiratory models under realistic exposure conditions.This research was funded by CERASAFE (www.cerasafe.eu; accessed on 26 October 2021), with the support of ERA-NET SIINN (project id:16) and the Portuguese Foundation for Science and Technology (FCT; SIINN/0004/2014). This work was also supported by the NanoBioBarriers project (PTDC/MED-TOX/31162/2017), co-financed by the Operational Program for Competitiveness and Internationalization (POCI) through European Regional Development Funds (FEDER/FNR) and FCT; Spanish Ministry of Science and Innovation (projects PCIN-2015-173-C02-01 and CEX2018-000794-S-Severo Ochoa), and by the Romanian National Authority for Scientific Research and Innovation (CCCDI-UEFISCDI, project number 29/2016 within PNCDI III). M.J. Bessa (SFRH/BD/120646/2016) and F. Brandão (SFRH/BD/101060/2014) are recipients of FCT PhD scholarships under the framework of Human Capital Operating Program (POCH) and European Union funding. The Doctoral Program in Biomedical Sciences, of the ICBAS—University of Porto, offered additional funds. S. Fraga thanks FCT for funding through program DL 57/2016–Norma transitória (Ref. DL-57/INSA-06/2018). Thanks are also due to FCT/MCTES for the financial support to EPIUnit (info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/UIDB/04750/2020/PT)

    Role of GP82 in the Selective Binding to Gastric Mucin during Oral Infection with Trypanosoma cruzi

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    Oral infection by Trypanosoma cruzi has been the primary cause of recent outbreaks of acute Chagas' diseases. This route of infection may involve selective binding of the metacyclic trypomastigote surface molecule gp82 to gastric mucin as a first step towards invasion of the gastric mucosal epithelium and subsequent systemic infection. Here we addressed that question by performing in vitro and in vivo experiments. A recombinant protein containing the complete gp82 sequence (J18), a construct lacking the gp82 central domain (J18*), and 20-mer synthetic peptides based on the gp82 central domain, were used for gastric mucin binding and HeLa cell invasion assays, or for in vivo experiments. Metacyclic trypomastigotes and J18 bound to gastric mucin whereas J18* failed to bind. Parasite or J18 binding to submaxillary mucin was negligible. HeLa cell invasion by metacyclic forms was not affected by gastric mucin but was inhibited in the presence of submaxillary mucin. Of peptides tested for inhibition of J18 binding to gastric mucin, the inhibitory peptide p7 markedly reduced parasite invasion of HeLa cells in the presence of gastric mucin. Peptide p7*, with the same composition as p7 but with a scrambled sequence, had no effect. Mice fed with peptide p7 before oral infection with metacyclic forms developed lower parasitemias than mice fed with peptide p7*. Our results indicate that selective binding of gp82 to gastric mucin may direct T. cruzi metacyclic trypomastigotes to stomach mucosal epithelium in oral infection

    The Effect of Exercise Training on Diastolic and Systolic Function After Acute Myocardial Infarction: A Randomized Study

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    After acute myocardial infarction (AMI), diastolic dysfunction is frequent and an important determinant of adverse outcome. However, few interventions have proven to be effective in improving diastolic function. We aimed to determine the effect of exercise training on diastolic and systolic function after AMI.One month after AMI, 188 patients were prospectively randomized (1:1) to an 8-week supervised program of endurance and resistance exercise training (n = 86; 55.9 ± 10.8 years) versus standard of care (n = 89; 55.4 ± 10.3 years). All patients were submitted to detailed echocardiography and cardiopulmonary exercise test, at baseline and immediately after the study. Diastolic function was evaluated by the determination of tissue-Doppler derived early diastolic velocities (E' velocity at the septal and lateral sides of mitral annulus) and by the E/E' (ratio between the E wave velocity from mitral inflow and the E' velocity) as recommended in the consensus document for diastolic function assessment.At the end of the study, there was no significant change in E' septal velocity or E/E' septal ratio in the exercise group. We observed a small, although nonsignificant, improvement in E' lateral (mean change 0.1 ± 2.0 cm/s; P = 0.40) and E/E' lateral ratio (mean change of -0.3 ± 2.5; P = 0.24), while patients in the control group had a nonsignificant reduction in E' lateral (mean change -0.4 ± 1.9 cm/s; P = 0.09) and an increase in E/E' lateral ratio (mean change + 0.3 ± 3.3; P = 0.34). No relevant changes occurred in other diastolic parameters. The exercise-training program also did not improve systolic function (either tissue Doppler systolic velocities or ejection fraction).Exercise capacity improved only in the exercise-training group, with an increase of 1.6 mL/kg/min in pVO2 (P = 0.001) and of 1.9 mL/kg/min in VO2 at anaerobic threshold (P < 0.001).After AMI, an 8-week endurance plus resistance exercise-training program did not significantly improve diastolic or systolic function, although it was associated with an improvement in exercise capacity parameters

    Interplay of LFV and slepton mass splittings at the LHC as a probe of the SUSY seesaw

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    We study the impact of a type-I SUSY seesaw concerning lepton flavour violation (LFV) both at low-energies and at the LHC. The study of the di-lepton invariant mass distribution at the LHC allows to reconstruct some of the masses of the different sparticles involved in a decay chain. In particular, the combination with other observables renders feasible the reconstruction of the masses of the intermediate sleptons involved in χ20~χ10 \chi_2^0\to \tilde \ell \,\ell \to \ell \,\ell\,\chi_1^0 decays. Slepton mass splittings can be either interpreted as a signal of non-universality in the SUSY soft breaking-terms (signalling a deviation from constrained scenarios as the cMSSM) or as being due to the violation of lepton flavour. In the latter case, in addition to these high-energy processes, one expects further low-energy manifestations of LFV such as radiative and three-body lepton decays. Under the assumption of a type-I seesaw as the source of neutrino masses and mixings, all these LFV observables are related. Working in the framework of the cMSSM extended by three right-handed neutrino superfields, we conduct a systematic analysis addressing the simultaneous implications of the SUSY seesaw for both high- and low-energy lepton flavour violation. We discuss how the confrontation of slepton mass splittings as observed at the LHC and low-energy LFV observables may provide important information about the underlying mechanism of LFV.Comment: 50 pages, 42 eps Figures, typos correcte

    Bond strength of different endodontic sealers to dentin: push-out test

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    OBJECTIVE: The aim of this in vitro study was to evaluate the bond strength of different root canal sealers to dentin. MATERIAL AND METHODS: Forty extracted single-rooted human teeth were examined and the coronal and middle thirds of the canals were prepared with a 1.50 mm post drill (FibreKor Post System, Pentron). The teeth were allocated in two experimental groups, irrigated with 2.5% NaOCl+17% EDTA or saline solution (control group) and instrumented using Race rotary files (FKG) to a size #40 at the working length. Then, the groups were divided into four subgroups and filled with Epiphany sealer (Group 1), EndoREZ (Group 2), AH26 (Group 3) and Grossman's Sealer (Group 4). After 2 weeks of storage in 100% humidity at 37ºC, all teeth were sectioned transversally into 2-mm-thick discs. Push-out tests were performed at a cross-head speed of 1 mm/min using a universal testing machine. The maximum load at failure was recorded and expressed in MPa. RESULTS: Means (±SD) in root canals irrigated with 2.5% NaOCl and 17% EDTA were: G1 (21.6±6.0), G2 (15.2±3.7), G3 (14.6±4.5) and G4 (11.7±4.1).Two-way ANOVA and Tukey's test showed the highest bond strength for the Epiphany's group (p< 0.01) when compared to the other tested sealers. Saline solution decreased the values of bond-strength (p<0.05) for all sealers. CONCLUSION: Epiphany sealer presented higher bond strength values to dentin in both irrigating protocols, and the use of 2.5% NaOCl and 17% EDTA increased the bond strength values for all sealers

    Spatial distribution of the risk of dengue fever in southeast Brazil, 2006-2007

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    Background: Many factors have been associated with circulation of the dengue fever virus and vector, although the dynamics of transmission are not yet fully understood. The aim of this work is to estimate the spatial distribution of the risk of dengue fever in an area of continuous dengue occurrence. Methods: This is a spatial population-based case-control study that analyzed 538 cases and 727 controls in one district of the municipality of Campinas, Sao Paulo, Brazil, from 2006-2007, considering socio-demographic, ecological, case severity, and household infestation variables. Information was collected by in-home interviews and inspection of living conditions in and around the homes studied. Cases were classified as mild or severe according to clinical data, and they were compared with controls through a multinomial logistic model. A generalized additive model was used in order to include space in a non-parametric fashion with cubic smoothing splines. Results: Variables associated with increased incidence of all dengue cases in the multiple binomial regression model were: higher larval density (odds ratio (OR) = 2.3 (95%CI: 2.0-2.7)), reports of mosquito bites during the day (OR = 1.8 (95%CI: 1.4-2.4)), the practice of water storage at home (OR = 2.5 (95%CI: 1.4, 4.3)), low frequency of garbage collection (OR = 2.6 (95%CI: 1.6-4.5)) and lack of basic sanitation (OR = 2.9 (95%CI: 1.8-4.9)). Staying at home during the day was protective against the disease (OR = 0.5 (95%CI: 0.3-0.6)). When cases were analyzed by categories (mild and severe) in the multinomial model, age and number of breeding sites more than 10 were significant only for the occurrence of severe cases (OR = 0.97, (95%CI: 0.96-0.99) and OR = 2.1 (95%CI: 1.2-3.5), respectively. Spatial distribution of risks of mild and severe dengue fever differed from each other in the 2006/2007 epidemic, in the study area. Conclusions: Age and presence of more than 10 breeding sites were significant only for severe cases. Other predictors of mild and severe cases were similar in the multiple models. The analyses of multinomial models and spatial distribution maps of dengue fever probabilities suggest an area-specific epidemic with varying clinical and demographic characteristics

    Relationship Between Sonic Hedgehog Protein, Brain-Derived Neurotrophic Factor and Oxidative Stress in Autism Spectrum Disorders

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    The etiology of autism spectrum disorders (ASD) is not well known but oxidative stress has been suggested to play a pathological role. We report here that the serum levels of Sonic hedgehog (SHH) protein and brain-derived neurotrophic factor (BDNF) might be linked to oxidative stress in ASD. By using the whole blood or polymorphonuclear leukocytes, we demonstrated that autistic children produced a significantly higher level of oxygen free radicals (OFR). In addition, we found significantly higher levels of serum SHH protein in children with mild as well as severe form of autism. We also found that the serum level of BDNF was significantly reduced in autistic children with mild form of the disorder but not with severe form of the disorder. Our findings are the first to report a correlation between SHH, BDNF and OFR in autistic children, suggesting a pathological role of oxidative stress and SHH in autism spectrum disorders

    The Trypanosoma cruzi Sylvio X10 strain maxicircle sequence: the third musketeer

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    <p>Abstract</p> <p>Background</p> <p>Chagas disease has a diverse pathology caused by the parasite <it>Trypanosoma cruzi</it>, and is indigenous to Central and South America. A pronounced feature of the trypanosomes is the kinetoplast, which is comprised of catenated maxicircles and minicircles that provide the transcripts involved in uridine insertion/deletion RNA editing. <it>T. cruzi </it>exchange genetic material through a hybridization event. Extant strains are grouped into six discrete typing units by nuclear markers, and three clades, A, B, and C, based on maxicircle gene analysis. Clades A and B are the more closely related. Representative clade B and C maxicircles are known in their entirety, and portions of A, B, and C clades from multiple strains show intra-strain heterogeneity with the potential for maxicircle taxonomic markers that may correlate with clinical presentation.</p> <p>Results</p> <p>To perform a genome-wide analysis of the three maxicircle clades, the coding region of clade A representative strain Sylvio X10 (a.k.a. Silvio X10) was sequenced by PCR amplification of specific fragments followed by assembly and comparison with the known CL Brener and Esmeraldo maxicircle sequences. The clade A rRNA and protein coding region maintained synteny with clades B and C. Amino acid analysis of non-edited and 5'-edited genes for Sylvio X10 showed the anticipated gene sequences, with notable frameshifts in the non-edited regions of Cyb and ND4. Comparisons of genes that undergo extensive uridine insertion and deletion display a high number of insertion/deletion mutations that are likely permissible due to the post-transcriptional activity of RNA editing.</p> <p>Conclusion</p> <p>Phylogenetic analysis of the entire maxicircle coding region supports the closer evolutionary relationship of clade B to A, consistent with uniparental mitochondrial inheritance from a discrete typing unit TcI parental strain and studies on smaller fragments of the mitochondrial genome. Gene variance that can be corrected by RNA editing hints at an unusual depth for maxicircle taxonomic markers, which will aid in the ability to distinguish strains, their corresponding symptoms, and further our understanding of the <it>T. cruzi </it>population structure. The prevalence of apparently compromised coding regions outside of normally edited regions hints at undescribed but active mechanisms of genetic exchange.</p
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