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1.
Res Q Exerc Sport ; : 1-10, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980761

RESUMO

Handball is a body-contact Olympic ball sport that is characterized by fast-paced defensive and offensive actions. Players must coordinate explosive movements (e.g. changing of direction) and handball-specific skills (e.g. passing). Maximizing performance requires a systematic approach to training that includes physical, psychological, technical, and tactical preparation. Purpose: The aim of this study is to determine the effects of movement-based (MOV; unspecific sport stimulus) or game-based (GAM; sport-specific stimulus) flywheel resistance training intervention in highly trained youth handball players. Method:Twenty-five highly trained youth male handball players completed two sessions per week of flywheel resistance training (MOV, n = 12; GAM, n = 13) over the 7-week intervention period. Change-of-direction tests (180º change-of-direction speed test of both legs and test) and handball-throwing test were conducted before and after the intervention. Results: Both groups significantly improved V-cut, and 180º Change-of-direction speed test performance (p < .05; d = 0.79-2.05). Notwithstanding, the GAM group demonstrated greater improvements in V-cut and COD180ASY compared with the MOV group (p < .05) with small effect. Handball throwing speed performance remained unchanged independently of training condition (p > .05). Conclusions: These findings provide further support for the training principle of "specificity" and highlight the importance of including a game-based training stimulus during resistance training. This is a key consideration for coaches wanting to enhance physical performance in youth handball players.

2.
Sports (Basel) ; 12(6)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38921849

RESUMO

The present study investigated the mediating effects of emotional intelligence and self-esteem between youth sports participation and life satisfaction, as well as the comparative effects of different types of sports involvement (team, individual, and non-participation) on these selected variables. A sample of 1053 Portuguese adolescents (612 girls and 441 boys), aged between 12 and 18 years (M = 14.40; SD = 1.55), completed the following self-report measures: the Wong and Law Emotional Intelligence Scale, the Rosenberg Self-Esteem Scale, and the Satisfaction with Life Scale. The structural equation modeling results indicated a complete mediating role of two emotional intelligence dimensions (use of emotion and self-emotional appraisal) and self-esteem in the relationship between sports participation and adolescents' life satisfaction. Team sport participants reported higher emotional intelligence and self-esteem scores than their non-sport participant counterparts who revealed lower levels of emotion use than their individual sport participant peers. These findings provide novel insights into the potential emotional and psychological mechanisms underlying the association between youth sports participation and life satisfaction.

4.
Front Immunol ; 15: 1329098, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38357541

RESUMO

Background: GBPs (guanylate binding proteins), an evolutionary ancient protein family, play a key role in the host's innate immune response against bacterial, parasitic and viral infections. In Humans, seven GBP genes have been described (GBP1-7). Despite the interest these proteins have received over the last years, evolutionary studies have only been performed in primates, Tupaia and rodents. These have shown a pattern of gene gain and loss in each family, indicative of the birth-and-death evolution process. Results: In this study, we analysed the evolution of this gene cluster in several bat species, belonging to the Yangochiroptera and Yinpterochiroptera sub-orders. Detailed analysis shows a conserved synteny and a gene expansion and loss history. Phylogenetic analysis showed that bats have GBPs 1,2 and 4-6. GBP2 has been lost in several bat families, being present only in Hipposideidae and Pteropodidae. GBPs1, 4 and 5 are present mostly as single-copy genes in all families but have suffered duplication events, particularly in Myotis myotis and Eptesicus fuscus. Most interestingly, we demonstrate that GBP6 duplicated in a Chiroptera ancestor species originating two genes, which we named GBP6a and GBP6b, with different subsequent evolutionary histories. GBP6a underwent several duplication events in all families while GBP6b is present as a single copy gene and has been lost in Pteropodidae, Miniopteridae and Desmodus rotundus, a Phyllostomidae. With 14 and 15 GBP genes, Myotis myotis and Eptesicus fuscus stand out as having far more copies than all other studied bat species. Antagonistically, Pteropodidae have the lowest number of GBP genes in bats. Conclusion: Bats are important reservoirs of viruses, many of which have become zoonotic diseases in the last decades. Further functional studies on bats GBPs will help elucidate their function, evolutionary history, and the role of bats as virus reservoirs.


Assuntos
Quirópteros , Viroses , Vírus , Animais , Humanos , Quirópteros/genética , Filogenia , Zoonoses
5.
Front Immunol ; 15: 1303089, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38348040

RESUMO

Guanylate binding proteins (GBPs) are an evolutionarily ancient family of proteins that are widely distributed among eukaryotes. They belong to the dynamin superfamily of GTPases, and their expression can be partially induced by interferons (IFNs). GBPs are involved in the cell-autonomous innate immune response against bacterial, parasitic and viral infections. Evolutionary studies have shown that GBPs exhibit a pattern of gene gain and loss events, indicative for the birth-and-death model of evolution. Most species harbor large GBP gene clusters that encode multiple paralogs. Previous functional and in-depth evolutionary studies have mainly focused on murine and human GBPs. Since rabbits are another important model system for studying human diseases, we focus here on lagomorphs to broaden our understanding of the multifunctional GBP protein family by conducting evolutionary analyses and performing a molecular and functional characterization of rabbit GBPs. We observed that lagomorphs lack GBP3, 6 and 7. Furthermore, Leporidae experienced a loss of GBP2, a unique duplication of GBP5 and a massive expansion of GBP4. Gene expression analysis by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) and transcriptome data revealed that leporid GBP expression varied across tissues. Overexpressed rabbit GBPs localized either uniformly and/or discretely to the cytoplasm and/or to the nucleus. Oryctolagus cuniculus (oc)GBP5L1 and rarely ocGBP5L2 were an exception, colocalizing with the trans-Golgi network (TGN). In addition, four ocGBPs were IFN-inducible and only ocGBP5L2 inhibited furin activity. In conclusion, from an evolutionary perspective, lagomorph GBPs experienced multiple gain and loss events, and the molecular and functional characteristics of ocGBP suggest a role in innate immunity.


Assuntos
Lagomorpha , Animais , Coelhos , Humanos , Camundongos , Lagomorpha/metabolismo , Proteínas de Transporte , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Imunidade Inata/genética , Interferons/metabolismo
6.
Animals (Basel) ; 14(2)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38254386

RESUMO

Studying proteins associated with sex chromosomes can provide insights into sex-specific proteins. Membrane proteins accessible through the cell surface may serve as excellent targets for diagnostic, therapeutic, or even technological purposes, such as sperm sexing technologies. In this context, proteins encoded by sex chromosomes have the potential to become targets for X- or Y-chromosome-bearing spermatozoa. Due to the limited availability of proteomic studies on rabbit spermatozoa and poorly annotated databases for rabbits compared to humans, a bioinformatic analysis of the available rabbit X chromosome proteome (RX), as well as the human X (HX) and Y (HY) chromosomes proteome, was conducted to identify potential targets that could be accessible from the cell surface and predict which of the potential targets identified in humans might also exist in rabbits. We identified 100, 211, and 3 proteins associated with the plasma membrane or cell surface for RX, HX, and HY, respectively, of which 61, 132, and 3 proteins exhibit potential as targets as they were predicted to be accessible from the cell surface. Cross-referencing the potential HX targets with the rabbit proteome revealed an additional 60 proteins with the potential to be RX targets, resulting in a total of 121 potential RX targets. In addition, at least 53 possible common HX and RX targets have been previously identified in human spermatozoa, emphasizing their potential as targets of X-chromosome-bearing spermatozoa. Further proteomic studies on rabbit sperm will be essential to identify and validate the usefulness of these proteins for application in rabbit sperm sorting techniques as targets of X-chromosome-bearing spermatozoa.

7.
Genome Biol Evol ; 15(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37988574

RESUMO

The innate immune system of mammals is formed by a complex web of interacting proteins, which together constitute the first barrier of entry for infectious pathogens. Genes from the E3-ubiquitin ligase tripartite motif (TRIM) family have been shown to play an important role in the innate immune system by restricting the activity of different retrovirus species. For example, TRIM5 and TRIM22 have both been associated with HIV restriction and are regarded as crucial parts of the antiretroviral machinery of mammals. Our analyses of positive selection corroborate the great significance of these genes for some groups of mammals. However, we also show that many species lack TRIM5 and TRIM22 altogether. By analyzing a large number of mammalian genomes, here we provide the first comprehensive view of the evolution of these genes in eutherians, showcasing that the pattern of accumulation of TRIM genes has been dissimilar across mammalian orders. Our data suggest that these differences are caused by the evolutionary plasticity of the immune system of eutherians, which have adapted to use different strategies to combat retrovirus infections. Altogether, our results provide insights into the dissimilar evolution of a representative family of restriction factors, highlighting an example of adaptive and idiosyncratic evolution in the innate immune system.


Assuntos
Fatores de Restrição Antivirais , Proteínas , Animais , Proteínas com Motivo Tripartido/genética , Proteínas/genética , Ubiquitina-Proteína Ligases/genética , Mamíferos/genética , Mamíferos/metabolismo , Eutérios/metabolismo
8.
PLoS One ; 18(9): e0291917, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37733773

RESUMO

The purpose of this study was to understand the contribution of each performance indicator to evaluate match performance of football referees. Thirty-four elite Referee Match Observers (RMOs) from the Portuguese FA participated voluntarily in the study. From the official assessment sheet of each game, the referee's game score was categorized in two groups according to referee's game score: i) Referees with a Low Score (LFS) and ii) Referees with High Score (HFS). A multivariable binary logistic regression model was used to assess the relationship between the Performance Indicators (PIs) of the dimensions i) game difficulty and game intervention and ii) disciplinary actions and game management in relation to the referee's match assessment score. The model proposed revealed that only the PIs negative application of the laws of the game and referee teamwork, from the dimension disciplinary actions and game management, significantly defined the final game referee's assessment score. This study suggests that the PIs scored by the RMOs contributed in a different way to the referee's game score. The model explains 60.4% of the referee's game score based on the variables referee teamwork and negative application of the laws of the game.


Assuntos
Futebol , Humanos , Etnicidade , Modelos Logísticos
9.
Front Immunol ; 14: 1192460, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37600766

RESUMO

Background: Immunoglobulin A (IgA) is the mammalian mucosal antibody, providing an important line of defense against pathogens. With 15 IgA subclasses, the European rabbit has an extremely complex IgA system, strikingly more complex than most other mammals, which have only one IgA or, in the case of hominoids, two IgA subclasses. Similar to the two hominoid primate IGHA genes, the expansion of the rabbit IGHA genes appears to have begun in an ancestral lagomorph since multiple IgA copies were found by Southern blot analysis for the genera Sylvilagus, Lepus, and Ochotona. Results: To gain a better insight into the extraordinary lagomorph IgA evolution, we sequenced, for the first time, expressed IgA genes for two Lepus species, L. europaeus and L. granatensis. These were aligned with the 15 rabbit IgA isotypes, and evolutionary analyses were conducted. The obtained phylogenetic tree shows that the Lepus IgA sequences cluster with and among the rabbit IgA isotypes, and the interspecies and intraspecies nucleotide genetic distances are similar. A comparison of the amino acid sequences of the Lepus and rabbit IgA confirms that there are two trans-species polymorphisms and that the rabbit and Lepus sequences share a common genetic pool. In fact, the main differences between the studied leporids IgAs reside in the characteristics of the hinge region. Conclusion: The Lepus IgA sequences we have obtained strongly suggest that the great expansion of the leporid IGHA genes occurred in a common ancestral species and was then maintained in the descendants. A strong selective pressure caused the extraordinary expansion of the IGHA genes but then subsided, leading to the maintenance of the acquired polymorphisms in the descendants, with little subsequent divergence. This is a unique evolutionary pattern in which an ancient gene expansion has been maintained for approximately 18 million years.


Assuntos
Lebres , Lagomorpha , Animais , Coelhos , Explosões , Imunoglobulina A/genética , Isotipos de Imunoglobulinas , Filogenia
10.
Front Microbiol ; 14: 1213685, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37577422

RESUMO

Interferon-inducible transmembrane proteins (IFITMs) are a family of transmembrane proteins. The subgroup of immunity-related (IR-)IFITMs is involved in adaptive and innate immune responses, being especially active against viruses. Here, we suggest that IFITMs should be classified as (1) a canonical IFITM gene cluster, which is located on the same chromosome, and (2) IFITM retrogenes, with a random and unique location at different positions within the genome. Phylogenetic analyses of the canonical cluster revealed the existence of three novel groups of primate IFITMs (pIFITM) in the IR-IFITM clade: the prosimian pIFITMs(pro), the new world monkey pIFITMs(nwm) and the old world monkey pIFITMs(owm). Therefore, we propose a new nomenclature: IR-pIFITM1, IR-pIFITM2, IR-pIFITM3, IR-pIFITMnwm, IR-pIFITMowm, and IR-pIFITMpro. We observed divergent evolution for pIFITM5 and pIFITM10, and evidence for concerted evolution and a mechanism of birth-and-death evolution model for the IR-pIFITMs. In contrast, the IFITMs scattered throughout the genomes possessed features of retrogenes retrotransposed by class 1 transposable elements. The origin of the IFITM retrogenes correspond to more recent events. We hypothesize that the transcript of a canonical IFITM3 has been constantly retrotransposed using class 1 transposable elements resulting in the IFITM retro(pseudo)genes. The unique pattern of each species has most likely been caused by constant pseudogenization and loss of the retro(pseudo)genes. This suggests a third mechanism of evolution for the IR-IFITMs in primates, similar to the birth-and-death model of evolution, but via a transposable element mechanism, which resulted in retro(pseudo)genes.

12.
Virol J ; 20(1): 103, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37237382

RESUMO

The European rabbit (Oryctolagus cuniculus) populations of the Iberian Peninsula have been severely affected by the emergence of the rabbit haemorrhagic disease virus (RHDV) Lagovirus europaeus/GI.2 (RHDV2/b). Bushflies and blowflies (Muscidae and Calliphoridae families, respectively) are important RHDV vectors in Oceania, but their epidemiological role is unknown in the native range of the European rabbit. In this study, scavenging flies were collected between June 2018 and February 2019 in baited traps at one site in southern Portugal, alongside a longitudinal capture-mark-recapture study of a wild European rabbit population, aiming to provide evidence of mechanical transmission of GI.2 by flies. Fly abundance, particularly from Calliphoridae and Muscidae families, peaked in October 2018 and in February 2019. By employing molecular tools, we were able to detect the presence of GI.2 in flies belonging to the families Calliphoridae, Muscidae, Fanniidae and Drosophilidae. The positive samples were detected during an RHD outbreak and absent in samples collected when no evidence of viral circulation in the local rabbit population was found. We were able to sequence a short viral genomic fragment, confirming its identity as RHDV GI.2. The results suggest that scavenging flies may act as mechanical vectors of GI.2 in the native range of the southwestern Iberian subspecies O. cuniculus algirus. Future studies should better assess their potential in the epidemiology of RHD and as a tool for monitoring viral circulation in the field.


Assuntos
Infecções por Caliciviridae , Dípteros , Vírus da Doença Hemorrágica de Coelhos , Lagovirus , Animais , Coelhos , Lagovirus/genética , Infecções por Caliciviridae/epidemiologia , Filogenia , Vírus da Doença Hemorrágica de Coelhos/genética
13.
Int J Mol Sci ; 24(5)2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36901962

RESUMO

The control of infections by the vertebrate adaptive immune system requires careful modulation to optimize defense and minimize harm to the host. The Fc receptor-like (FCRL) genes encode immunoregulatory molecules homologous to the receptors for the Fc portion of immunoglobulin (FCR). To date, nine different genes (FCRL1-6, FCRLA, FCRLB and FCRLS) have been identified in mammalian organisms. FCRL6 is located at a separate chromosomal position from the FCRL1-5 locus, has conserved synteny in mammals and is situated between the SLAMF8 and DUSP23 genes. Here, we show that this three gene block underwent repeated duplication in Dasypus novemcinctus (nine-banded armadillo) resulting in six FCRL6 copies, of which five appear functional. Among 21 mammalian genomes analyzed, this expansion was unique to D. novemcinctus. Ig-like domains that derive from the five clustered FCRL6 functional gene copies show high structural conservation and sequence identity. However, the presence of multiple non-synonymous amino acid changes that would diversify individual receptor function has led to the hypothesis that FCRL6 endured subfunctionalization during evolution in D. novemcinctus. Interestingly, D. novemcinctus is noteworthy for its natural resistance to the Mycobacterium leprae pathogen that causes leprosy. Because FCRL6 is chiefly expressed by cytotoxic T and NK cells, which are important in cellular defense responses against M. leprae, we speculate that FCRL6 subfunctionalization could be relevant for the adaptation of D. novemcinctus to leprosy. These findings highlight the species-specific diversification of FCRL family members and the genetic complexity underlying evolving multigene families critical for modulating adaptive immune protection.


Assuntos
Tatus , Hanseníase , Animais , Tatus/genética , Tatus/microbiologia , Mycobacterium leprae/genética , Hanseníase/genética , Genoma , Células Matadoras Naturais , Receptores Fc/genética
14.
Med Microbiol Immunol ; 212(2): 141-152, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35416510

RESUMO

Guanylate binding proteins (GBPs) represent an evolutionary ancient protein family widely distributed among eukaryotes. They are interferon (IFN)-inducible guanosine triphosphatases that belong to the dynamin superfamily. GBPs are known to have a major role in the cell-autonomous innate immune response against bacterial, parasitic and viral infections and are also involved in inflammasome activation. Evolutionary studies depicted that GBPs present a pattern of gain and loss of genes in each family with several genes pseudogenized and some genes more divergent, indicative for the birth-and-death evolution process. Most species harbor large GBP gene clusters encoding multiple paralogs. Previous functional studies mainly focused on mouse and human GBPs, but more data are becoming available, broadening the understanding of this multifunctional protein family. In this review, we will provide new insights and give a broad overview about GBP evolution, conservation and their roles in all studied species, including plants, invertebrates and vertebrates, revealing how far the described features of GBPs can be transferred to other species.


Assuntos
Proteínas de Transporte , Proteínas de Ligação ao GTP , Humanos , Animais , Camundongos , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Imunidade Inata , Interferons/metabolismo , Inflamassomos/metabolismo
15.
Front Immunol ; 13: 1009387, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466819

RESUMO

Background: The transcytosis of polymeric immunoglobulins, IgA and IgM, across the epithelial barrier to the luminal side of mucosal tissues is mediated by the polymeric immunoglobulin receptor (pIgR). At the luminal side the extracellular ligand binding region of pIgR, the secretory component (SC), is cleaved and released bound to dimeric IgA (dIgA), protecting it from proteolytic degradation, or in free form, protecting the mucosa form pathogens attacks. The pIgR was first cloned for rabbit in early 1980's and since then has been described for all vertebrates, from fish to mammals. The existence of more than one functional pIgR alternative-spliced variant in the European rabbit, the complete pIgR as other mammals and a shorter pIgR lacking two SC exons, raised the question whether other lagomorphs share the same characteristics and how has the PIGR gene evolved in these mammals. Results: To investigate these questions, we sequenced expressed pIgR genes for other leporid genus, Lepus spp., and obtained and aligned pIgR sequences from representative species of all mammalian orders. The obtained mammalian phylogeny, as well as the Bayesian inference of evolutionary rates and genetic distances, show that Lagomorpha pIgR is evolving at a higher substitution rate. Codon-based analyses of positive selection show that mammalian pIgR is evolving under strong positive selection, with strong incidence in the domains excised from the rabbit short pIgR isoform. We further confirmed that the hares also express the two rabbit pIgR isoforms. Conclusions: The Lagomorpha pIgR unique evolutionary pattern may reflect a group specific adaptation. The pIgR evolution may be linked to the unusual expansion of IgA genes observed in lagomorphs, or to neofunctionalization in this group. Further studies are necessary to clarify the driving forces behind the unique lagomorph pIgR evolution.


Assuntos
Lagomorpha , Receptores de Imunoglobulina Polimérica , Animais , Coelhos , Receptores de Imunoglobulina Polimérica/genética , Taxa de Mutação , Teorema de Bayes , Mamíferos/genética , Imunoglobulina A
16.
Pathogens ; 11(12)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36558859

RESUMO

Dogs and cats are potential sources of infection for some zoonotic diseases such as Q fever, caused by Coxiella burnetii, a multiple host pathogen. Q fever outbreaks in dogs and cats have been related with parturition and abortion events, and ticks have a potential role in the transmission of this pathogen. This study aimed to screen for C. burnetii in dogs and cats, and in ticks collected from infested animals. An observational descriptive study was conducted in Portugal at two time points nine years apart, 2012 and 2021. Sera obtained from dogs and cats (total n = 294) were tested for C. burnetii antibodies using a commercial ELISA adapted for multi-species detection. C. burnetii DNA was screened by qPCR assay targeting IS1111 in uterine samples and in ticks. A decrease in the exposure to C. burnetii was observed in cats from 17.2% (95% CI: 5.8−35.8%) in 2012 to 0.0% in 2021, and in dogs from 12.6% (95% CI: 7.7−19.0%) in 2012 to 1.7% (95% CI: 0.3−9.1%) in 2021 (p < 0.05). Overall, and despite differences in the samples, rural habitat seems to favour the exposure to C. burnetii. The DNA of C. burnetii was not detected in ticks. The low seropositivity observed in 2021 and the absence of C. burnetii DNA in the tested samples, suggest that dogs and cats from Portugal are not often exposed to the pathogen. Nevertheless, the monitoring of C. burnetii infection in companion animals is an important tool to prevent human outbreaks, considering the zoonotic potential for owners and veterinarians contacting infected animals, mainly dogs and cats from rural areas which often come into contact with livestock.

17.
Front Immunol ; 13: 981815, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36159800

RESUMO

The European rabbit (Oryctolagus cuniculus) was the first animal model used to understand human diseases like rabies and syphilis. Nowadays, the rabbit is still used to study several human infectious diseases like syphilis, HIV and papillomavirus. However, due to several mainly practical reasons, it has been replaced as an animal model by mice (Mus musculus). The rabbit and mouse share a recent common ancestor and are classified in the superorder Glires which arose at approximately 82 million years ago (mya). These species diverged from the Primates' ancestor at around 92 million years ago and, as such, one expects the rabbit-human and mouse-human genetic distances to be very similar. To evaluate this hypothesis, we developed a set of tools for automatic data extraction, sequence alignment and similarity study, and a web application for visualization of the resulting data. We aligned and calculated the genetic distances for 2793 innate immune system genes from human, rabbit and mouse using sequences available in the NCBI database. The obtained results show that the rabbit-human genetic distance is lower than the mouse-human genetic distance for 88% of these genes. Furthermore, when we considered only genes with a difference in genetic distance higher than 0.05, this figure increase to 93%. These results can be explained by the increase of the mutation rates in the mouse lineage suggested by some authors and clearly show that, at least looking to the genetic distance to human genes, the European rabbit is a better model to study innate immune system genes than the mouse.


Assuntos
Sífilis , Animais , Modelos Animais de Doenças , Humanos , Imunidade Inata/genética , Camundongos , Filogenia , Coelhos , Alinhamento de Sequência
18.
Front Immunol ; 13: 907342, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35784276

RESUMO

Immunoglobulin A provides a major line of defence against pathogens and plays a key role in the maintenance of the commensal microbiota in the intestinal tract. Having been shown to be more effective at tumour cell killing than IgG and strongly active against pathogens present in the mucosae, IgA antibodies have been attracting significant attention in recent years for use as therapeutic antibodies. To improve their therapeutic potential, bioengineered IgA forms with increased serum half-life and neutralizing abilities have been developed but the IgA hinge, which impacts susceptibility to bacterial proteases and ability to bridge between target and effector cells, has not yet been explored. The European rabbit has 15 IgA subclasses with exclusive hinge region motifs and varying lengths, constituting a unique model to evaluate the functional capabilities offered by incorporation of longer IgA hinges into immunoglobulins. Hinge regions from rabbit IgAs, featuring different lengths and sequences, were inserted into human IgA1 heavy chain to substitute the IgA1 hinge. These hinges did not appear to affect antigen binding nor the ability of the engineered chimeric IgA1 to bind and trigger FcαRI, as detected by IgA-mediated cell agglutination and release of superoxide by neutrophils. All rabbit hinge-human IgA1 hybrids were resistant to Clostridrum ramosum IgA protease enzyme digestion, as predicted by the lack of the cleavage site in the rabbit hinges. Some IgA1s featuring long rabbit hinges were cleaved by Neisseria meningitidis IgA1 protease cleavage type 1 or 2 enzymes, despite the lack of the predicted cleavage sites. More interestingly, the hybrid featuring the rabbit IgA15 hinge was not affected by any of the IgA proteases. The IgA15 hinge is longer than that found in human IgA1 and is composed by a unique motif with a stretch of nine consecutive Ser residues. These characteristics allow the preservation of a long hinge, with associated ability to bridge distantly spaced antigens and provide higher avidity binding, while remaining resistant to IgA protease degradation. The data suggest that the rabbit Cα15 hinge represents an interesting alternative hinge sequence for therapeutic human IgA antibodies that remains resistant to proteolytic cleavage.


Assuntos
Imunoglobulina A , Neisseria meningitidis , Animais , Imunoglobulina A/metabolismo , Neisseria meningitidis/metabolismo , Peptídeo Hidrolases , Coelhos , Serina Endopeptidases/metabolismo
19.
Transbound Emerg Dis ; 69(5): e3024-e3035, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35810475

RESUMO

Estimation of the diagnostic performance of serological tests often relies on another test assumed as a reference or on samples of known infection status, yet both are seldom available for emerging pathogens in wildlife. Longitudinal disease serological data can be analysed through multi-event capture-mark-recapture (MECMR) models accounting for the uncertainty in state assignment, allowing us to estimate epidemiological parameters such as incidence and mortality. We hypothesized that by estimating the uncertainty in state assignment, MECMR models estimate the diagnostic performance of serological tests for rabbit haemorrhagic disease virus (RHDV) and myxoma virus (MYXV). We evaluated this hypothesis on longitudinal serological data of three tests of RHDV and one test of MYXV in two populations of the European rabbit (Oryctolagus cuniculus algirus). First, we selected the optimal cut-off threshold for each test using finite mixture models, a reference method not relying on reference tests or samples. Second, we used MECMR models to compare the diagnostic sensitivity (Se) and specificity (Sp) of the three tests for RHDV. Third, we compared the estimates of diagnostic performance by MECMR and finite mixture models across a range of cut-off values. The MECMR models showed that the RHDV test employing GI.2 antigens (Se: 100%) outperformed two tests employing GI.1 antigens (Se: 21.7% ± 8.6% and 8.7% ± 5.9%). At their selected cut-offs (2.0 for RHDV GI.2 and 2.4 for MYXV), the estimates of Se and Sp were concordant between the MECMR and finite mixture models. Over the duration of the study (May 2018 to September 2020), the monthly survival of European rabbits seropositive for MYXV was significantly higher than that of seronegative rabbits (82.7% ± 4.9% versus 61.5% ± 12.7%) at the non-fenced site. We conclude that MECMR models can reliably estimate the diagnostic performance of serological tests for RHDV and MYXV in European rabbits. This conclusion could extend to other diagnostic tests and host-pathogen systems. Longitudinal disease surveillance data analysed through MECMR models allow the validation of diagnostic tests for emerging pathogens in novel host species while simultaneously estimating epidemiological parameters.


Assuntos
Infecções por Caliciviridae , Vírus da Doença Hemorrágica de Coelhos , Myxoma virus , Mixoma , Animais , Infecções por Caliciviridae/diagnóstico , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/veterinária , Mixoma/veterinária , Coelhos , Testes Sorológicos/veterinária
20.
Front Psychol ; 13: 885765, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35712138

RESUMO

We examined the effect of physiological workload on gaze behaviour during defensive performance in 2 vs. 1 +goalkeeper game situations in football. Twenty-two players were assigned to either a high- or low-performing group based on a validated measure of tactical performance. A total of 12 game sequences (trials) were presented under high- and low-workload conditions. At the end of each sequence, participants were asked to indicate their perceived exertion using the Rating Scale of Mental Effort and the Borg Scale. The low- and high-workload conditions were defined when the players achieved 60 and 90% of their maximal heart rate, respectively, as per their performance in the Yo-Yo Intermittent Recovery Test. Visual search behaviours were recorded using Tobii Pro eye-movement registration glasses. Players reported higher rates of perceived exertion on the high- compared to low-workload condition. Participants in the low-performing group increased their average fixation duration and decreased the number of fixations and number of fixation locations from the low- to high-workload conditions. The low- and high-performing groups displayed different visual search strategies with regards the areas of interest fixated upon. Participants in the high-performing group focused on the SpaceFrontPlayer, followed by Ball, and AnotherOpponent. The low-performing group spent more time focusing on the SpaceFrontPlayer and SpacePlayer than Ball and AnotherOpponent. It appears that physiological workload and tactical expertise interact in constraining visual search behaviours in football players. Coaches and practitioners should consider ways to manipulate individual and task constraints while attending to the close interplay between physiological workload, visual behaviour, and tactical performance during practise.

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