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1.
Plant Physiol ; 187(1): 158-173, 2021 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-34618135

RESUMO

Because of limited free diffusion in the cytoplasm, viruses must use active transport mechanisms to move intracellularly. Nevertheless, how the plant single-stranded DNA begomoviruses hijack the host intracytoplasmic transport machinery to move from the nucleus to the plasmodesmata remains enigmatic. Here, we identified nuclear shuttle protein (NSP)-interacting proteins from Arabidopsis (Arabidopsis thaliana) by probing a protein microarray and demonstrated that the cabbage leaf curl virus NSP, a facilitator of the nucleocytoplasmic trafficking of viral (v)DNA, interacts in planta with an endosomal vesicle-localized, plant-specific syntaxin-6 protein, designated NSP-interacting syntaxin domain-containing protein (NISP). NISP displays a proviral function, unlike the syntaxin-6 paralog AT2G18860 that failed to interact with NSP. Consistent with these findings, nisp-1 mutant plants were less susceptible to begomovirus infection, a phenotype reversed by NISP complementation. NISP-overexpressing lines accumulated higher levels of vDNA than wild-type. Furthermore, NISP interacted with an NSP-interacting GTPase (NIG) involved in NSP-vDNA nucleocytoplasmic translocation. The NISP-NIG interaction was enhanced by NSP. We also showed that endosomal NISP associates with vDNA. NISP may function as a docking site for recruiting NIG and NSP into endosomes, providing a mechanism for the intracytoplasmic translocation of the NSP-vDNA complex toward and from the cell periphery.


Assuntos
Arabidopsis , Begomovirus , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/virologia , Begomovirus/fisiologia , Núcleo Celular/metabolismo
2.
Nature ; 520(7549): 679-82, 2015 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-25707794

RESUMO

Plants and plant pathogens are subject to continuous co-evolutionary pressure for dominance, and the outcomes of these interactions can substantially impact agriculture and food security. In virus-plant interactions, one of the major mechanisms for plant antiviral immunity relies on RNA silencing, which is often suppressed by co-evolving virus suppressors, thus enhancing viral pathogenicity in susceptible hosts. In addition, plants use the nucleotide-binding and leucine-rich repeat (NB-LRR) domain-containing resistance proteins, which recognize viral effectors to activate effector-triggered immunity in a defence mechanism similar to that employed in non-viral infections. Unlike most eukaryotic organisms, plants are not known to activate mechanisms of host global translation suppression to fight viruses. Here we demonstrate in Arabidopsis that the constitutive activation of NIK1, a leucine-rich repeat receptor-like kinase (LRR-RLK) identified as a virulence target of the begomovirus nuclear shuttle protein (NSP), leads to global translation suppression and translocation of the downstream component RPL10 to the nucleus, where it interacts with a newly identified MYB-like protein, L10-INTERACTING MYB DOMAIN-CONTAINING PROTEIN (LIMYB), to downregulate translational machinery genes fully. LIMYB overexpression represses ribosomal protein genes at the transcriptional level, resulting in protein synthesis inhibition, decreased viral messenger RNA association with polysome fractions and enhanced tolerance to begomovirus. By contrast, the loss of LIMYB function releases the repression of translation-related genes and increases susceptibility to virus infection. Therefore, LIMYB links immune receptor LRR-RLK activation to global translation suppression as an antiviral immunity strategy in plants.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/imunologia , Arabidopsis/virologia , Begomovirus/imunologia , Imunidade Inata , Imunidade Vegetal , Biossíntese de Proteínas/imunologia , Proteínas Serina-Treonina Quinases/metabolismo , Transporte Ativo do Núcleo Celular , Núcleo Celular/metabolismo , Regulação para Baixo , Regulação da Expressão Gênica de Plantas , Tolerância Imunológica , Ligação Proteica , Biossíntese de Proteínas/genética , Proteína Ribossômica L10 , Proteínas Ribossômicas/metabolismo , Fatores de Transcrição/metabolismo
3.
Genomics ; 112(3): 2410-2417, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31981699

RESUMO

Described as "junk" DNA, pseudogenes are dead structures of previously active genes present in genomes. Pseudogenes are categorized into two main classes: processed pseudogenes, formed through retrotransposition, and non-processed pseudogenes, typically originated from gene decay following duplication events. The term "processed pseudogene" has changed to "retrocopy" since they are likely to evolve new functional roles and became a retrogene. Here, we surveyed 38,080 retrocopies from chimpanzee, dog, human, mouse, and rat genomes to assess their potential adaptive value. The retrocopies inserted in the same chromosome of the parental gene have higher chances of remain potentially "active" (absence of premature stop codons and frameshifts) (~26.1%), while those placed into a different chromosome have a twofold decrease chance of continuing potentially "active" (~7.52%). The genomic context of their placement seems associated with their expression. Retrocopies placed in intragenic regions and the same sense of the "host" gene have higher chances of being expressed relative to other genomic contexts. The proximity of retrocopies to their parental gene is associated with a lower decay rate, and their location likely influence their expression. Thus, despite their unclear role, retrocopies are probably involved in adaptive processes. Our results evidence natural selection acting in retrocopies.


Assuntos
Pseudogenes , Animais , Cromossomos de Mamíferos , Cães , Evolução Molecular , Expressão Gênica , Genômica , Humanos , Camundongos , Ratos , Seleção Genética
4.
Genomics ; 112(6): 4722-4731, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32818633

RESUMO

Lung cancer is the type of cancer causing most deaths in humans, with 234,030 new cases of lung cancer diagnosed in the United States in 2018. Recently, Tumor suppressor genes (TSGs) or the control of its pathway became promising drug targets for cancer therapy. A diverse group of TSGs is involved in progression and metastasis of lung cancer. Here, we surveyed nine highly significant mutated genes in 20 mammalian genomes to assess signatures of adaptive evolution using maximum likelihood approaches. We found that three genes (APC, RB1, and TP53) are under strong positive selection, influencing amino acids located in functionally important protein domains, such as three sites in APC found in the APC_N_CC domain, which is responsible for the binding to beta-catenin armadillo repeats that regulate beta-catenin level (beta-catenin is a transcription factor and its misregulation lead to malignant transformation of normal cells). Such sites substitutions mostly increase the stability of the domain. Moreover, substitution of some other sites found in important motifs, such as codon 47 (proline-directed kinase motif) in TP53, modify the phosphorylation activity of TP53 playing a key role in cancer risk. Our findings will open recommendation to drug targeting sites and will foster further research to understand better these proteins function.


Assuntos
Proteína da Polipose Adenomatosa do Colo/genética , Neoplasias Pulmonares/genética , Proteínas de Ligação a Retinoblastoma/genética , Seleção Genética , Proteína Supressora de Tumor p53/genética , Ubiquitina-Proteína Ligases/genética , Sequência de Aminoácidos , Animais , Evolução Molecular , Humanos , Mamíferos/genética
5.
Clin Oral Investig ; 25(5): 3095-3103, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33047204

RESUMO

OBJECTIVES: This study aimed to evaluate the effects of nanohydroxyapatite (nHAp) particles on the morphological, chemical, physical, and biological properties of chitosan electrospun nanofibers. MATERIALS AND METHODS: nHAp particles with a 1.67 Ca/P ratio were synthesized via the aqueous precipitation method, incorporated into chitosan polymer solution (0.5 wt%), and electrospun into nHAp-loaded fibers (ChHa fibers). Neat chitosan fibers (nHAp-free, Ch fibers) were used as the control. The electrospun fiber mats were characterized using morphological, topographical, chemical, thermal, and a range of biological (antibacterial, antibiofilm, cell viability, and alkaline phosphatase [ALP] activity) analyses. Data were analyzed using ANOVA and Tukey's test (α = 0.05). RESULTS: ChHa fibers demonstrated a bead-like morphology, with thinner (331 ± 110 nm) and smoother (Ra = 2.9 ± 0.3 µm) distribution as compared to the control fibers. Despite showing similar cell viability and ALP activity to Ch fibers, the ChHa fibers demonstrated greater antibacterial potential against most tested bacteria (except for P. intermedia), and higher antibiofilm activity against P. gingivalis biofilm. CONCLUSIONS: The incorporation of nHAp particles did not jeopardize the overall morphology, topography, physical, and biological characteristics of the chitosan nanofibers. CLINICAL RELEVANCE: The combination of nHAp particles with chitosan can be used to engineer bioactive, electrospun composite nanofibers with potential applications in regenerative dentistry.


Assuntos
Quitosana , Nanofibras , Quitosana/farmacologia , Durapatita , Polímeros
6.
Bioinformatics ; 35(11): 1862-1869, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30358816

RESUMO

MOTIVATION: Determining whether a trait and phylogeny share some degree of phylogenetic signal is a flagship goal in evolutionary biology. Signatures of phylogenetic signal can assist the resolution of a broad range of evolutionary questions regarding the tempo and mode of phenotypic evolution. However, despite the considerable number of strategies to measure it, few and limited approaches exist for categorical traits. Here, we used the concept of Shannon entropy and propose the δ statistic for evaluating the degree of phylogenetic signal between a phylogeny and categorical traits. RESULTS: We validated δ as a measure of phylogenetic signal: the higher the δ-value the higher the degree of phylogenetic signal between a given tree and a trait. Based on simulated data we proposed a threshold-based classification test to pinpoint cases of phylogenetic signal. The assessment of the test's specificity and sensitivity suggested that the δ approach should only be applied to 20 or more species. We have further tested the performance of δ in scenarios of branch length and topology uncertainty, unbiased and biased trait evolution and trait saturation. Our results showed that δ may be applied in a wide range of phylogenetic contexts. Finally, we investigated our method in 14 360 mammalian gene trees and found that olfactory receptor genes are significantly associated with the mammalian activity patterns, a result that is congruent with expectations and experiments from the literature. Our application shows that δ can successfully detect molecular signatures of phenotypic evolution. We conclude that δ represents a useful measure of phylogenetic signal since many phenotypes can only be measured in categories. AVAILABILITY AND IMPLEMENTATION: https://github.com/mrborges23/delta_statistic. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Filogenia , Animais , Mamíferos , Fenótipo
7.
Mycopathologia ; 184(5): 585-595, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31471824

RESUMO

This study aimed to evaluate the effects of cold atmospheric pressure plasma (CAPP) jet on Trichophyton rubrum growth, germination and adherence to nail. The effects of plasma jet on T. rubrum conidia germination and on mycelial growth were evaluated by in vitro assays. An ex vivo nail infection model was used to evaluate the effects on conidia adherence and infection. Biochemical analyses of nail fragments exposed or not to CAPP were performed by attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. Plasma jet exposure for 10 and 15 min completely inhibited mycelial growth after only one exposure. Fifteen minutes of exposure could reduce conidia germination in suspension. Fungal suspensions exposed to plasma jet for 10 and 15 min were not able to infect nail specimens. These results were corroborated by ATR-FTIR analyses of nail fragments. In conclusion, single exposure to CAPP for 15 min was able to inhibit fungal growth, adherence and infection capacity. The results suggest that cold atmospheric plasma jet can be a promising alternative for the treatment of onychomycoses caused by T. rubrum.


Assuntos
Pressão Atmosférica , Adesão Celular/efeitos dos fármacos , Gases em Plasma , Tinha/prevenção & controle , Trichophyton/efeitos dos fármacos , Voluntários Saudáveis , Humanos , Modelos Teóricos , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Unhas/microbiologia , Trichophyton/crescimento & desenvolvimento
8.
Appl Environ Microbiol ; 84(3)2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29150506

RESUMO

Swinholides are 42-carbon ring polyketides with a 2-fold axis of symmetry. They are potent cytotoxins that disrupt the actin cytoskeleton. Swinholides were discovered from the marine sponge Theonella sp. and were long suspected to be produced by symbiotic bacteria. Misakinolide, a structural variant of swinholide, was recently demonstrated to be the product of a symbiotic heterotrophic proteobacterium. Here, we report the production of swinholide A by an axenic strain of the terrestrial cyanobacterium Nostoc sp. strain UHCC 0450. We located the 85-kb trans-AT polyketide synthase (PKS) swinholide biosynthesis gene cluster from a draft genome of Nostoc sp. UHCC 0450. The swinholide and misakinolide biosynthesis gene clusters share an almost identical order of catalytic domains, with 85% nucleotide sequence identity, and they group together in phylogenetic analysis. Our results resolve speculation around the true producer of swinholides and demonstrate that bacteria belonging to two distantly related phyla both produce structural variants of the same natural product. In addition, we described a biosynthesis cluster from Anabaena sp. strain UHCC 0451 for the synthesis of the cytotoxic and antifungal scytophycin. All of these biosynthesis gene clusters were closely related to each other and created a group of cytotoxic macrolide compounds produced by trans-AT PKSs of cyanobacteria and proteobacteria.IMPORTANCE Many of the drugs in use today originate from natural products. New candidate compounds for drug development are needed due to increased drug resistance. An increased knowledge of the biosynthesis of bioactive compounds can be used to aid chemical synthesis to produce novel drugs. Here, we show that a terrestrial axenic culture of Nostoc cyanobacterium produces swinholides, which have been previously found only from marine sponge or samples related to them. Swinholides are polyketides with a 2-fold axis of symmetry, and they are potent cytotoxins that disrupt the actin cytoskeleton. We describe the biosynthesis gene clusters of swinholide from Nostoc cyanobacteria, as well as the related cytotoxic and antifungal scytophycin from Anabaena cyanobacteria, and we study the evolution of their trans-AT polyketide synthases. Interestingly, swinholide is closely related to misakinolide produced by a symbiotic heterotrophic proteobacterium, demonstrating that bacteria belonging to two distantly related phyla and different habitats can produce similar natural products.


Assuntos
Proteínas de Bactérias/genética , Toxinas Marinhas/biossíntese , Família Multigênica , Nostoc/genética , Policetídeo Sintases/genética , Proteínas de Bactérias/metabolismo , Toxinas Marinhas/genética , Nostoc/metabolismo , Filogenia , Policetídeo Sintases/metabolismo , Análise de Sequência de DNA
9.
Genet Mol Biol ; 40(1 suppl 1): 292-304, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28199446

RESUMO

Due to the limited coding capacity of viral genomes, plant viruses depend extensively on the host cell machinery to support the viral life cycle and, thereby, interact with a large number of host proteins during infection. Within this context, as plant viruses do not harbor translation-required components, they have developed several strategies to subvert the host protein synthesis machinery to produce rapidly and efficiently the viral proteins. As a countermeasure against infection, plants have evolved defense mechanisms that impair viral infections. Among them, the host-mediated translational suppression has been characterized as an efficient mean to restrict infection. To specifically suppress translation of viral mRNAs, plants can deploy susceptible recessive resistance genes, which encode translation initiation factors from the eIF4E and eIF4G family and are required for viral mRNA translation and multiplication. Additionally, recent evidence has demonstrated that, alternatively to the cleavage of viral RNA targets, host cells can suppress viral protein translation to silence viral RNA. Finally, a novel strategy of plant antiviral defense based on suppression of host global translation, which is mediated by the transmembrane immune receptor NIK1 (nuclear shuttle protein (NSP)-Interacting Kinase1), is discussed in this review.

10.
BMC Genomics ; 17: 371, 2016 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-27193938

RESUMO

BACKGROUND: Bones have been subjected to considerable selective pressure throughout vertebrate evolution, such as occurred during the adaptations associated with the development of powered flight. Powered flight evolved independently in two extant clades of vertebrates, birds and bats. While this trait provided advantages such as in aerial foraging habits, escape from predators or long-distance travels, it also imposed great challenges, namely in the bone structure. RESULTS: We performed comparative genomic analyses of 89 bone-associated genes from 47 avian genomes (including 45 new), 39 mammalian, and 20 reptilian genomes, and demonstrate that birds, after correcting for multiple testing, have an almost two-fold increase in the number of bone-associated genes with evidence of positive selection (~52.8 %) compared with mammals (~30.3 %). Most of the positive-selected genes in birds are linked with bone regulation and remodeling and thirteen have been linked with functional pathways relevant to powered flight, including bone metabolism, bone fusion, muscle development and hyperglycemia levels. Genes encoding proteins involved in bone resorption, such as TPP1, had a high number of sites under Darwinian selection in birds. CONCLUSIONS: Patterns of positive selection observed in bird ossification genes suggest that there was a period of intense selective pressure to improve flight efficiency that was closely linked with constraints on body size.


Assuntos
Aves/genética , Evolução Molecular , Voo Animal , Osteogênese/genética , Adaptação Biológica , Animais , Evolução Biológica , Aves/classificação , Tamanho Corporal , Análise por Conglomerados , Biologia Computacional/métodos , Genoma , Genômica/métodos , Mamíferos/genética , Filogenia , Seleção Genética
11.
Plant Cell Physiol ; 57(5): 1098-114, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27016095

RESUMO

The onset of leaf senescence is a highly regulated developmental change that is controlled by both genetics and the environment. Senescence is triggered by massive transcriptional reprogramming, but functional information about its underlying regulatory mechanisms is limited. In the current investigation, we performed a functional analysis of the soybean (Glycine max) osmotic stress- and endoplasmic reticulum (ER) stress-induced NAC transcription factor GmNAC81 during natural leaf senescence using overexpression studies and reverse genetics. GmNAC81-overexpressing lines displayed accelerated flowering and leaf senescence but otherwise developed normally. The precocious leaf senescence of GmNAC81-overexpressing lines was associated with greater Chl loss, faster photosynthetic decay and higher expression of hydrolytic enzyme-encoding GmNAC81 target genes, including the vacuolar processing enzyme (VPE), an executioner of vacuole-triggered programmed cell death (PCD). Conversely, virus-induced gene silencing-mediated silencing of GmNAC81 delayed leaf senescence and was associated with reductions in Chl loss, lipid peroxidation and the expression of GmNAC81 direct targets. Promoter-reporter studies revealed that the expression pattern of GmNAC81 was associated with senescence in soybean leaves. Our data indicate that GmNAC81 is a positive regulator of age-dependent senescence and may integrate osmotic stress- and ER stress-induced PCD responses with natural leaf senescence through the GmNAC81/VPE regulatory circuit.


Assuntos
Apoptose , Estresse do Retículo Endoplasmático , Regulação da Expressão Gênica de Plantas , Glycine max/fisiologia , Fatores de Transcrição/metabolismo , Animais , Senescência Celular , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Pressão Osmótica , Folhas de Planta/genética , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas/genética , Glycine max/genética , Fatores de Tempo , Fatores de Transcrição/genética
12.
BMC Genomics ; 16: 783, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-26466891

RESUMO

BACKGROUND: Despite the relevance of the eukaryotic endoplasmic reticulum (ER)-stress response as an integrator of multiple stress signals into an adaptive response, knowledge about these ER-mediated cytoprotective pathways in soybean (Glycine max) is lacking. Here, we searched for genes involved in the highly conserved unfolded protein response (UPR) and ER stress-induced plant-specific cell death signaling pathways in the soybean genome. METHODS: Previously characterized Arabidopsis UPR genes were used as prototypes for the identification of the soybean orthologs and the in silico assembly of the UPR in soybean, using eggNOG v4.0 software. Functional studies were also conducted by analyzing the transcriptional activity of soybean UPR transducers. RESULTS: As a result of this search, we have provided a complete profile of soybean UPR genes with significant predicted protein similarities to A. thaliana UPR-associated proteins. Both arms of the plant UPR were further examined functionally, and evidence is presented that the soybean counterparts are true orthologs of previously characterized UPR transducers in Arabidopsis. The bZIP17/bZI28 orthologs (GmbZIP37 and GmbZIP38) and ZIP60 ortholog (GmbZIP68) from soybean have similar structural organizations as their Arabidopsis counterparts, were induced by ER stress and activated an ERSE- and UPRE-containing BiP promoter. Furthermore, the transcript of the putative substrate of GmIREs, GmbZIP68, harbors a canonical site for IRE1 endonuclease activity and was efficiently spliced under ER stress conditions. In a reverse approach, we also examined the Arabidopsis genome for components of a previously characterized ER stress-induced cell death signaling response in soybean. With the exception of GmERD15, which apparently does not possess an Arabidopsis ortholog, the Arabidopsis genome harbors conserved GmNRP, GmNAC81, GmNAC30 and GmVPE sequences that share significant structural and sequence similarities with their soybean counterparts. These results suggest that the NRP/GmNAC81 + GmNAC30/VPE regulatory circuit may transduce cell death signals in plant species other than soybean. CONCLUSIONS: Our in silico analyses, along with current and previous functional data, permitted generation of a comprehensive overview of the ER stress response in soybean as a framework for functional prediction of ER stress signaling components and their possible connections with multiple stress responses.


Assuntos
Estresse do Retículo Endoplasmático/genética , Retículo Endoplasmático/genética , Genoma de Planta , Glycine max/genética , Arabidopsis/genética , Simulação por Computador , Estresse do Retículo Endoplasmático/fisiologia , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Regiões Promotoras Genéticas , Transdução de Sinais , Resposta a Proteínas não Dobradas/genética
13.
Plant Biotechnol J ; 13(9): 1300-1311, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25688422

RESUMO

Begomovirus-associated epidemics currently threaten tomato production worldwide due to the emergence of highly pathogenic virus species and the proliferation of a whitefly B biotype vector that is adapted to tomato. To generate an efficient defence against begomovirus, we modulated the activity of the immune defence receptor nuclear shuttle protein (NSP)-interacting kinase (NIK) in tomato plants; NIK is a virulence target of the begomovirus NSP during infection. Mutation of T474 within the kinase activation loop promoted the constitutive activation of NIK-mediated defences, resulting in the down-regulation of translation-related genes and the suppression of global translation. Consistent with these findings, transgenic lines harbouring an activating mutation (T474D) were tolerant to the tomato-infecting begomoviruses ToYSV and ToSRV. This phenotype was associated with reduced loading of coat protein viral mRNA in actively translating polysomes, lower infection efficiency and reduced accumulation of viral DNA in systemic leaves. Our results also add some relevant insights into the mechanism underlying the NIK-mediated defence. We observed that the mock-inoculated T474D-overexpressing lines showed a constitutively infected wild-type transcriptome, indicating that the activation of the NIK-mediated signalling pathway triggers a typical response to begomovirus infection. In addition, the gain-of-function mutant T474D could sustain an activated NIK-mediated antiviral response in the absence of the virus, further confirming that phosphorylation of Thr-474 is the crucial event that leads to the activation of the kinase.


Assuntos
Begomovirus/fisiologia , Doenças das Plantas/virologia , Imunidade Vegetal , Proteínas de Plantas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Solanum lycopersicum/virologia , Genes de Plantas , Solanum lycopersicum/fisiologia , Mutação , Doenças das Plantas/imunologia , Proteínas de Plantas/genética , Transdução de Sinais/genética , Proteínas Virais/metabolismo
14.
J Hered ; 105(2): 237-52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24344252

RESUMO

Gene duplication is an important mechanism that leads to genetic novelty. Different, nonexclusive processes are likely involved, and many adaptive and nonadaptive events may contribute to the maintenance of duplicated genes. In some teleosts, a duplicate copy of the mammalian ortholog Hemopexin (HPX) is present, known as the warm temperature acclimation-related protein (WAP65). Both WAP65 and HPX have been associated with iron homeostasis due to the affinity to bind the toxic-free heme circulating in the blood stream. We have assessed the evolutionary dynamics of WAP65 and HPX genes to understand the adaptive role of positive selection at both nucleotide and amino acid level. Our results showed an asymmetrical evolution between the paralogs WAP65-1 and WAP65-2 after duplication with a slight acceleration of the evolutionary rate in WAP65-1, but not in WAP65-2, and few sites contributing to the functional distinction between the paralogs, whereas the majority of the protein remained under negative selection or relaxed negative selection. WAP65-1 is functionally more distinct from the ancestral protein function than WAP65-2. HPX is phylogenetically closer to WAP65-2 but even so functional divergence was detected between both proteins. In addition, HPX showed a fast rate of evolution when compared with both WAP65-1 and WAP65-2 genes. The assessed 3-dimensional (3-D) structure of WAP65-1 and WAP65-2 suggests that the functional differences detected are not causing noticeable structural changes in these proteins. However, such subtle changes between WAP65 paralogs may be important to understand the differential gene retention of both copies in 20 out of 30 teleosts species studied.


Assuntos
Aclimatação/genética , Peixes/genética , Hemopexina/química , Hemopexina/genética , Mamíferos/genética , Temperatura , Animais , Evolução Molecular , Proteínas de Peixes/genética , Duplicação Gênica , Filogenia , Conformação Proteica , Seleção Genética
15.
Trans R Soc Trop Med Hyg ; 118(6): 359-366, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38243827

RESUMO

BACKGROUND: Schistosoma mansoni is a parasitic disease of great magnitude for Brazilian public health. We aimed to analyse the temporal trend and spatial and spatiotemporal distribution of positivity rates for schistosomiasis mansoni in northeast Brazil. METHODS: This is a descriptive study with an ecological approach, carried out between 2005 and 2016. We calculated the positivity rate for the disease and then performed a segmented trend analysis (Joinpoint). For spatial analysis, we smoothed the positivity rates using the local empirical Bayesian method. We checked for spatial autocorrelation using Moran's global and local. Subsequently, we performed Kulldorff's space time sweep analysis. RESULTS: In the period under review, 7 745 650 tests were performed in the northeast, of which 577 793 were positive for Schistosoma mansoni. In the historical series of positivities, it is noted that the highest rates were in Sergipe, Alagoas and Pernambuco. The states of Alagoas and Sergipe showed higher positivity in relation to the average positivity of the northeast and of Brazil. The spatial analysis maps identify clusters of high risk of schistosomiasis cases, mainly in coastal municipalities. There was also stability in positivity rates in some states and the maintenance of endemic areas. CONCLUSIONS: Thus effective public health policies are needed in health education in order to reduce schistosomiasis positivity and improve the health conditions of the northeastern population.


Assuntos
Teorema de Bayes , Schistosoma mansoni , Esquistossomose mansoni , Análise Espaço-Temporal , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/prevenção & controle , Brasil/epidemiologia , Humanos , Animais , Masculino , Feminino , Saúde Pública , Criança , Análise Espacial
16.
Mol Biol Evol ; 29(12): 3887-98, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22844072

RESUMO

The mechanosensory lateral line, found only in fishes and amphibians, is an important sense organ associated with aquatic life. Lateral line patterns differ among teleost, the most diverse vertebrate taxa, hypothetically in response to selective pressures from different aquatic habitats. In this article, we conduct evolutionary genomic analyses of 34 genes associated with lateral line system development in teleosts to elucidate the significance of contrasting evolutionary rates and changes in the protein coding sequences. We find that duplicated copies of these genes are preferentially retained in the teleost genomes and that episodic events of positive selection have occurred in 22 of the 30 postduplication branches. In general, teleost genes evolved at a faster rate relative to their tetrapod counterparts, and the mutation rates of 26 of the 34 genes differed among teleosts and tetrapods. We conclude that following whole genome duplication, evolutionary rates and episodic events of positive selection on the lateral line system development genes might have been one of the factors favoring the subsequent adaptive radiation of teleosts into diverse habitats. These results provide the foundation for further detailed explorations into lateral line system genes and the evolution of diverse phenotypes and adaptations.


Assuntos
Adaptação Biológica/genética , Evolução Molecular , Peixes/genética , Genes Duplicados/genética , Genes/genética , Sistema da Linha Lateral/anatomia & histologia , Seleção Genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Códon/genética , Biologia Computacional , Peixes/anatomia & histologia , Sistema da Linha Lateral/fisiologia , Funções Verossimilhança , Dados de Sequência Molecular , Taxa de Mutação , Filogenia , Alinhamento de Sequência , Sintenia/genética
17.
Acta Trop ; 239: 106786, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36509130

RESUMO

Accidents with venomous animals correspond to the second cause of epidemiological notification in Brazil, with around 140 thousand cases registered in recent years, which constitutes a serious public health problem. This study aimed to analyze the epidemiological profile and the spatial and spatio-temporal patterns of the incidence of accidents by venomous animals in the Northeast region of Brazil, from 2008 to 2017. We carried out an epidemiological and observational study of an ecological nature, with tools for spatial analysis. To do so, we calculated the incidence rate of cases. The occurrence of spatial autocorrelation was verified and the spatial KullDorff statistics were used to identify risk clusters. A total of 486,001 cases were reported, of which 50.1% (244,122) of those affected were female, the age group most affected by accidents was >60 years, 70.6% (343,295) of accidents were caused by scorpions and 14.7% (71,620) by snakes. The state of Bahia had the highest number of accidents, followed by Pernambuco and Alagoas. The highest incidence rates are observed mainly in the states of Alagoas, Pernambuco, Maranhão and Bahia. There was an increase in accidents in the period studied. In addition, this study shows that the use of space tools collaborate positively to identify locations with a high incidence of accidents by venomous animals.


Assuntos
Acidentes , Peçonhas , Animais , Feminino , Masculino , Incidência , Brasil/epidemiologia , Estudos Retrospectivos , Análise Espaço-Temporal
18.
J Neurointerv Surg ; 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37524519

RESUMO

BACKGROUND: A new generation of modified surface flow diverters (FDs) and monotherapy using new antiplatelets may reduce both ischemic and hemorrhagic complications during the treatment of intracranial aneurysms. Previous preliminary safety analysis of distal unruptured intracranial aneurysms treated with the FD p48 MW HPC (phenox-Wallaby, Bochum, Germany) under antiplatelet monotherapy with prasugrel showed promising results. However, the long term outcomes of distal intracranial aneurysms treated with FDs under antiplatelet monotherapy are not known. METHODS: This was a single center, prospective, pivotal, open single arm study. The primary (safety) endpoint was absence of any new neurological deficits after treatment until the 24 month follow-up. The primary (efficacy) endpoint was the incidence of complete aneurysm occlusion 24 months after treatment. The secondary (efficacy) endpoints were any incidence of aneurysm dome reduction 24 months after treatment. RESULTS: 21 patients harboring 27 distal aneurysms of the anterior circulation were included. No patient had neurologic deficits in the time from treatment to the 24 month follow-up. Complete aneurysm occlusion occurred in 20 (74%) of 27 aneurysms at the 24 month follow-up. Four aneurysms (14.8%) had dome reduction, and three aneurysms (11.1%) remained unchanged. CONCLUSIONS: In this pilot trial, treatment of distal unruptured intracranial aneurysms with an FD under monotherapy with prasugrel, followed by monotherapy with aspirin, appeared to be safe and effective. Randomized studies with long term follow-up are needed to confirm these results.

19.
Environ Pollut ; 334: 122152, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37414119

RESUMO

Ethiprole, a phenylpyrazole insecticide, has been increasingly used in the Neotropical region to control stink bug pests in soybean and maize fields. However, such abrupt increases in use may have unintended effects on non-target organisms, including those inhabiting freshwater ecosystems. Here, we evaluated the effects of acute (96 h) sublethal exposure to ethiprole (up to 180 µg/L, which is equivalent to 0.013% of the recommended field dose) on biomarkers of stress in the gills, liver, and muscle of the Neotropical fish Astyanax altiparanae. We further recorded potential ethiprole-induced effects on the structural histology of A. altiparanae gills and liver. Our results showed that ethiprole exposure increased glucose and cortisol levels in a concentration-dependent manner. Ethiprole-exposed fish also exhibited higher levels of malondialdehyde and greater activity of antioxidant enzymes, such as glutathione-S-transferase and catalase, in both gills and liver. Furthermore, ethiprole exposure led to increased catalase activity and carbonylated protein levels in muscle. Morphometric and pathological analyses of the gills revealed that increasing ethiprole concentration resulted in hyperemia and loss of integrity of the secondary lamellae. Similarly, histopathological analysis of the liver demonstrated higher prevalence of necrosis and inflammatory infiltrates with increasing ethiprole concentration. Altogether, our findings demonstrated that sublethal exposure to ethiprole can trigger a stress response in non-target fish species, which may lead to potential ecological and economic imbalances in Neotropical freshwater systems.


Assuntos
Characidae , Poluentes Químicos da Água , Animais , Catalase/metabolismo , Ecossistema , Estresse Oxidativo , Poluentes Químicos da Água/metabolismo , Antioxidantes/metabolismo , Glutationa Transferase/metabolismo , Fígado/metabolismo , Brânquias/metabolismo , Peroxidação de Lipídeos
20.
J Adhes Dent ; 25(1): 1-12, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36633468

RESUMO

PURPOSE: To evaluate the effect of plasma-enhanced chemical vapor deposition (PECVD) with silicon hydride (SiH4) at different times on HT-zirconia surface characteristics and bonding of composite cement before and after thermocycling. MATERIALS AND METHODS: Blocks of HT zirconia were obtained, polished, sintered and divided into five groups, according to PECVD time (n = 31): Zr-30 (30 s), Zr-60 (60 s), Zr-120 (120 s) and Zr-300 (300 s). The control group (Zr-0) did not receive PECVD. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), energy dispersive spectroscopy (EDS) in conjunction with field-emission scanning electron microscopy (FE-SEM), x-ray photoelectron spectroscopy (XPS), goniometry, and profilometry tests were used for chemical and topographic characterization. Monobond N silane (Ivoclar Vivadent) was applied to the surface, and a cylinder of composite cement (Variolink N) was made (3 x 3 mm). Half of the specimens of each group were stored for 24 h or subjected to thermocycling (6 x 103 cycles). A shear bond strength (SBS) test was performed. Results were subjected to one-way ANOVA and Tukey's tests (α = 0.05). RESULTS: For experimental groups, XPS showed that formation of Si-O bonds contributed to increased surface free energy (SFE). FE-SEM and EDS showed that the longer the deposition time, the greater the amount of silicon on the surface. Zr-60 and Zr-300 presented higher and lower surface roughnesses, respectively. The silicon penetrated the microstructure, causing higher stress concentrations. The bond strength to composite cement was improved after all PECVD deposition times. CONCLUSION: The PECVD technique with SiH4, associated with chemical treatment with primer based on silane methacrylate, is a solely chemical surface treatment capable of maintaining bonding between composite cement and HT zirconia.


Assuntos
Colagem Dentária , Silício , Silanos , Propriedades de Superfície , Cimentos de Resina , Cimentos Dentários , Zircônio/química , Resistência ao Cisalhamento , Teste de Materiais , Cerâmica/química
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