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1.
BMC Bioinformatics ; 25(1): 278, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39192185

RESUMO

BACKGROUND: Honey bees are the principal commercial pollinators. Along with other arthropods, they are increasingly under threat from anthropogenic factors such as the incursion of invasive honey bee subspecies, pathogens and parasites. Better tools are needed to identify bee subspecies. Genomic data for economic and ecologically important organisms is increasing, but in its basic form its practical application to address ecological problems is limited. RESULTS: We introduce HBeeID a means to identify honey bees. The tool utilizes a knowledge-based network and diagnostic SNPs identified by discriminant analysis of principle components and hierarchical agglomerative clustering. Tests of HBeeID showed that it identifies African, Americas-Africanized, Asian, and European honey bees with a high degree of certainty even when samples lack the full 272 SNPs of HBeeID. Its prediction capacity decreases with highly admixed samples. CONCLUSION: HBeeID is a high-resolution genomic, SNP based tool, that can be used to identify honey bees and screen species that are invasive. Its flexible design allows for future improvements via sample data additions from other localities.


Assuntos
Polimorfismo de Nucleotídeo Único , Abelhas/genética , Abelhas/classificação , Animais , Polimorfismo de Nucleotídeo Único/genética , Genômica/métodos
2.
Int J Mol Sci ; 24(10)2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37240423

RESUMO

The development of immunogens that elicit broadly reactive neutralising antibodies (bNAbs) is the highest priority for an HIV vaccine. We have shown that a prime-boost vaccination strategy with vaccinia virus expressing the envelope glycoprotein gp120 of HIV-2 and a polypeptide comprising the envelope regions C2, V3 and C3 elicits bNAbs against HIV-2. We hypothesised that a chimeric envelope gp120 containing the C2, V3 and C3 regions of HIV-2 and the remaining parts of HIV-1 would elicit a neutralising response against HIV-1 and HIV-2. This chimeric envelope was synthesised and expressed in vaccinia virus. Balb/c mice primed with the recombinant vaccinia virus and boosted with an HIV-2 C2V3C3 polypeptide or monomeric gp120 from a CRF01_AG HIV-1 isolate produced antibodies that neutralised >60% (serum dilution 1:40) of a primary HIV-2 isolate. Four out of nine mice also produced antibodies that neutralised at least one HIV-1 isolate. Neutralising epitope specificity was assessed using a panel of HIV-1 TRO.11 pseudoviruses with key neutralising epitopes disrupted by alanine substitution (N160A in V2; N278A in the CD4 binding site region; N332A in the high mannose patch). The neutralisation of the mutant pseudoviruses was reduced or abolished in one mouse, suggesting that neutralising antibodies target the three major neutralising epitopes in the HIV-1 envelope gp120. These results provide proof of concept for chimeric HIV-1/HIV-2 envelope glycoproteins as vaccine immunogens that can direct the antibody response against neutralising epitopes in the HIV-1 and HIV-2 surface glycoproteins.


Assuntos
HIV-1 , Animais , Camundongos , HIV-2 , Anticorpos Anti-HIV , Anticorpos Amplamente Neutralizantes , Anticorpos Neutralizantes , Epitopos , Vaccinia virus , Glicoproteínas , Proteína gp120 do Envelope de HIV/genética
3.
Biologicals ; 62: 107-110, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31519539

RESUMO

Potency testing of tetanus antitoxin must be performed in vivo, in a very painful, stressful and prone to high variability assay. It is, therefore, mandatory to find alternatives to this kind of potency assessment. Immunochemical tests as ELISA or ToBI test are already available but usually results in a poor correlation to the in vivo protection. Considering research and development of mono and oligoclonal antibodies against tetanus and the improvement of equine polyclonal antitoxin production and control, we developed an alternative instrumental test for tetanus antitoxin by using surface plasmon resonance. Tetanus antitoxin from hyperimmune equine sera (16 batches) were tested and the results indicated excellent concordance and correlation to the in vivo test (Lin's ρ = 0.9). This innovative approach should now be improved in order to extend it to oligoclonal and monoclonal human antibodies aiming to replace mice for the potency assessment of tetanus antitoxin especially during research and development steps.


Assuntos
Anticorpos Monoclonais/análise , Ressonância de Plasmônio de Superfície , Antitoxina Tetânica/análise , Animais , Humanos
4.
BMC Gastroenterol ; 17(1): 119, 2017 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-29169329

RESUMO

BACKGROUND: Eradication of hepatitis C virus (HCV) using direct-acting agents (DAA) has been associated with a financial burden to health authorities worldwide. We aimed to evaluate the guideline-based treatment costs by DAAs from the perspective of the Brazilian Ministry of Health (BMoH). METHODS: The activity based costing method was used to estimate the cost for monitoring/treatment of genotype-1 (GT1) HCV patients by the following strategies: peg-interferon (PEG-IFN)/ribavirin (RBV) for 48 weeks, PEG-IFN/RBV plus boceprevir (BOC) or telaprevir (TEL) for 48 weeks, and sofosbuvir (SOF) plus daclastavir (DCV) or simeprevir (SIM) for 12 weeks. Costs were reported in United States Dollars without (US$) and with adjustment for purchasing power parity (PPP$). Drug costs were collected at the National Database of Health Prices and an overview of the literature was performed to assess effectiveness of SOF/DCV and SOF/SIM regimens in real-world cohorts. RESULTS: Treatment costs of GT1-HCV patients were PPP$ 43,176.28 (US$ 24,020.16) for PEG-IFN/RBV, PPP$ 71,196.03 (US$ 39,578.23) for PEG-IFN/RBV/BOC and PPP$ 86,250.33 (US$ 47,946.92) for PEG-IFN/RBV/TEL. Treatment by all-oral interferon-free regimens were the less expensive approach: PPP$ 19,761.72 (US$ 10,985.90) for SOF/DCV and PPP$ 21,590.91 (US$ 12,002.75) for SOF/SIM. The overview reported HCV eradication in up to 98% for SOF/DCV and 96% for SOF/SIM. CONCLUSION: Strategies with all oral interferon-free might lead to lower costs for management of GT1-HCV patients compared to IFN-based regimens in Brazil. This occurred mainly because of high discounts over international DAA prices due to negotiation between BMoH and pharmaceutical industries.


Assuntos
Antivirais/economia , Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Brasil , Carbamatos , Custos e Análise de Custo , Custos de Medicamentos , Genótipo , Hepatite C Crônica/economia , Hepatite C Crônica/genética , Hepatite C Crônica/patologia , Humanos , Imidazóis/economia , Imidazóis/uso terapêutico , Interferon-alfa/economia , Interferon-alfa/uso terapêutico , Cirrose Hepática/patologia , Oligopeptídeos/economia , Oligopeptídeos/uso terapêutico , Prolina/análogos & derivados , Prolina/economia , Prolina/uso terapêutico , Pirrolidinas , Ribavirina/economia , Ribavirina/uso terapêutico , Simeprevir/economia , Simeprevir/uso terapêutico , Sofosbuvir/economia , Sofosbuvir/uso terapêutico , Valina/análogos & derivados
5.
Int J Biometeorol ; 58(5): 887-99, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23686111

RESUMO

Different spatial interpolation techniques have been applied to construct objective bioclimatic maps of La Palma, Canary Islands. Interpolation of climatic data on this topographically complex island with strong elevation and climatic gradients represents a challenge. Furthermore, meteorological stations are not evenly distributed over the island, with few stations at high elevations. We carried out spatial interpolations of the compensated thermicity index (Itc) and the annual ombrothermic Index (Io), in order to obtain appropriate bioclimatic maps by using automatic interpolation procedures, and to establish their relation to potential vegetation units for constructing a climatophilous potential natural vegetation map (CPNV). For this purpose, we used five interpolation techniques implemented in a GIS: inverse distance weighting (IDW), ordinary kriging (OK), ordinary cokriging (OCK), multiple linear regression (MLR) and MLR followed by ordinary kriging of the regression residuals. Two topographic variables (elevation and aspect), derived from a high-resolution digital elevation model (DEM), were included in OCK and MLR. The accuracy of the interpolation techniques was examined by the results of the error statistics of test data derived from comparison of the predicted and measured values. Best results for both bioclimatic indices were obtained with the MLR method with interpolation of the residuals showing the highest R2 of the regression between observed and predicted values and lowest values of root mean square errors. MLR with correction of interpolated residuals is an attractive interpolation method for bioclimatic mapping on this oceanic island since it permits one to fully account for easily available geographic information but also takes into account local variation of climatic data.


Assuntos
Clima , Plantas , Análise Espacial , Modelos Lineares , Chuva , Espanha , Temperatura
6.
Environ Manage ; 54(5): 1121-30, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25047274

RESUMO

Human influence associated with land use may cause considerable biodiversity losses, namely in oceanic islands such as the Azores. Our goal was to identify plant indicator species across two gradients of increasing anthropogenic influence and management (arborescent and herbaceous communities) and determine similarity between plant communities of uncategorized vegetation plots to those in reference gradients using metrics derived from R programming. We intend to test and provide an expedient way to determine the conservation value of a given uncategorized vegetation plot based on the number of native, endemic, introduced, and invasive indicator species present. Using the metric IndVal, plant taxa with a significant indicator value for each community type in the two anthropogenic gradients were determined. A new metric, ComVal, was developed to assess the similarity of an uncategorized vegetation plot toward a reference community type, based on (i) the percentage of pre-defined indicator species from reference communities present in the vegetation plots, and (ii) the percentage of indicator species, specific to a given reference community type, present in the vegetation plot. Using a data resampling approach, the communities were randomly used as training or validation sets to classify vegetation plots based on ComVal. The percentage match with reference community types ranged from 77 to 100 % and from 79 to 100 %, for herbaceous and arborescent vegetation plots, respectively. Both IndVal and ComVal are part of a suite of useful tools characterizing plant communities and plant community change along gradients of anthropogenic influence without a priori knowledge of their biology and ecology.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/estatística & dados numéricos , Atividades Humanas/estatística & dados numéricos , Espécies Introduzidas/estatística & dados numéricos , Desenvolvimento Vegetal , Açores , Interpretação Estatística de Dados , Ecologia/métodos , Humanos , Dinâmica Populacional , Especificidade da Espécie
7.
AIDS ; 38(8): 1101-1110, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38349224

RESUMO

OBJECTIVES: To characterize the genetic diversity and drug resistance profiles of people with HIV-1 failing ART in Cape Verde (CV). DESIGN: Cross-sectional study conducted between January 2019 and December 2021 in 24 health centres on the islands of Santiago and São Vicente. METHODS: The HIV-1 pol gene was sequenced in individuals with a detectable viral load. HIV-1 genetic diversity was determined by phylogenetic analysis. Drug resistance mutation patterns and resistance phenotypes were estimated using the Stanford algorithm. RESULTS: Viral load was detected in 73 of 252 (29%) enrolled participants and sequencing data were produced for 58 (79%) participants. CRF02 AG strains predominated (46.5%), followed by subtype G (22.4%). Most patients (80%) had mutations conferring resistance to nonnucleoside reverse transcriptase inhibitors (NNRTIs) (67%), nucleoside reverse transcriptase inhibitors (55%), integrase inhibitors (10%) and/or protease inhibitors (7%) used in Cape Verde, a significant increase compared with a study conducted in 2010-2011. The most common mutations were M184V/I (43%), K103N/S (36%) and G190A/S (19%). NNRTI resistance was associated with younger age and exposure to two or more drug regimens. CONCLUSION: The HIV-1 epidemic in Cape Verde is mainly driven by CRF02_AG and subtype G. Resistance to NNRTIs and/or NRTIs is highly prevalent and resistance to LPV/r and DTG is emerging. Our results support the use of DTG-based first-line ART and protease inhibitor-based regimens for patients with virological failure, but emerging resistance to LPV/r and DTG is a concern. Continued monitoring of drug resistance is essential to ensure adequate healthcare for PWH in Cape Verde.


Assuntos
Farmacorresistência Viral , Variação Genética , Infecções por HIV , HIV-1 , Filogenia , Humanos , HIV-1/genética , HIV-1/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Masculino , Farmacorresistência Viral/genética , Feminino , Estudos Transversais , Adulto , Cabo Verde , Pessoa de Meia-Idade , Fármacos Anti-HIV/uso terapêutico , Fármacos Anti-HIV/farmacologia , Carga Viral , Adulto Jovem , Genótipo , Mutação , Adolescente , Produtos do Gene pol do Vírus da Imunodeficiência Humana/genética
8.
Retrovirology ; 10: 110, 2013 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-24156513

RESUMO

BACKGROUND: Differently from HIV-1, HIV-2 disease progression usually takes decades without antiretroviral therapy and the majority of HIV-2 infected individuals survive as elite controllers with normal CD4⁺ T cell counts and low or undetectable plasma viral load. Neutralizing antibodies (Nabs) are thought to play a central role in HIV-2 evolution and pathogenesis. However, the dynamic of the Nab response and resulting HIV-2 escape during acute infection and their impact in HIV-2 evolution and disease progression remain largely unknown. Our objective was to characterize the Nab response and the molecular and phenotypic evolution of HIV-2 in association with Nab escape in the first years of infection in two children infected at birth. RESULTS: CD4⁺ T cells decreased from about 50% to below 30% in both children in the first five years of infection and the infecting R5 viruses were replaced by X4 viruses within the same period. With antiretroviral therapy, viral load in child 1 decreased to undetectable levels and CD4+ T cells recovered to normal levels, which have been sustained at least until the age of 12. In contrast, viral load increased in child 2 and she progressed to AIDS and death at age 9. Beginning in the first year of life, child 1 raised high titers of antibodies that neutralized primary R5 isolates more effectively than X4 isolates, both autologous and heterologous. Child 2 raised a weak X4-specific Nab response that decreased sharply as disease progressed. Rate of evolution, nucleotide and amino acid diversity, and positive selection, were significantly higher in the envelope of child 1 compared to child 2. Rates of R5-to-X4 tropism switch, of V1 and V3 sequence diversification, and of convergence of V3 to a ß-hairpin structure were related with rate of escape from the neutralizing antibodies. CONCLUSION: Our data suggests that the molecular and phenotypic evolution of the human immunodeficiency virus type 2 envelope are related with the dynamics of the neutralizing antibody response providing further support for a model in which Nabs play an important role in HIV-2 pathogenesis.


Assuntos
Anticorpos Neutralizantes/imunologia , Evolução Molecular , Variação Genética , Anticorpos Anti-HIV/imunologia , Infecções por HIV/virologia , HIV-2/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Variação Antigênica , Criança , Pré-Escolar , Feminino , Infecções por HIV/imunologia , HIV-2/genética , Humanos , Lactente , Recém-Nascido , Dados de Sequência Molecular , Análise de Sequência de DNA , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética
9.
Environ Monit Assess ; 185(8): 6221-33, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23224646

RESUMO

The aim of this study was to assess the impact of anthropogenic disturbance on the partitioning of plant communities (species spectra) across a landcover gradient of community types, categorizing species on the basis of their biogeographic, ecological, and conservation status. We tested a multinomial model to generate species spectra and monitor changes in plant assemblages as anthropogenic disturbance rise, as well as the usefulness of this method to assess the conservation value of a given community. Herbaceous and arborescent communities were sampled in five Azorean islands. Margins were also sampled to account for edge effects. Different multinomial models were applied to a data set of 348 plant species accounting for differences in parameter estimates among communities and/or islands. Different levels of anthropogenic disturbance produced measurable changes on species spectra. Introduced species proliferated and indigenous species declined, as anthropogenic disturbance and management intensity increased. Species assemblages of relevance other than economic (i.e., native, endemic, threatened species) were enclosed not only in natural habitats, but also in human managed arborescent habitats, which can positively contribute for the preservation of indigenous species outside remnants of natural areas, depending on management strategies. A significant presence of invasive species in margin transects of most community types will contribute to an increase in edge effect that might facilitate invasion. The multinomial model developed in this study was found to be a novel and expedient tool to characterize the species spectra at a given community and its use could be extrapolated for other assemblages or organisms, in order to evaluate and forecast the conservation value of a site.


Assuntos
Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Açores , Biodiversidade , Ecossistema , Poluição Ambiental/estatística & dados numéricos , Espécies Introduzidas , Modelos Biológicos
10.
Biology (Basel) ; 11(5)2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35625478

RESUMO

Platypus cylindrus is the most common ambrosia beetle in stands of Quercus suber in Portugal. This insect farms specialized fungi in sapwood galleries, using its mycangia to carry and store these organisms. Some ectosymbiotic fungi carried by P. cylindrus are phytopathogenic and cause extensive tree mortality and severe economic losses. To understand the role of P. cylindrus fungal symbionts in stands of Q. suber we examined beetle galleries present in declining and/or dying cork oak trees during field surveys. Logs with active galleries were obtained in situ and from captured emerging beetles. Insects were aseptically dissected, and their mycangia and intestine were retrieved. Morphological and molecular profiles of fungal isolates obtained from cultured insect parts were carried out to accurately characterize and identify isolated fungi. Molecular characterizations were performed with DNA sequence data from four loci, i.e., LSU, SSU, 5.8S-ITS2-28S, and TUB. Morphological results consistently showed a collection of Ophiostoma-like fungal axenic isolates, while phylogenies inferred that this collection constitutes an undescribed taxon reported herein for the first time in association with P. cylindrus in Portuguese cork oak stands. The novel species was erected as Ceratocystiopsis quercina sp. nov. and constitutes a new phytopathogenic fungal species associated with symptoms of vegetative cork oak decline.

11.
PLoS One ; 17(12): e0276618, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36548381

RESUMO

In Portugal, the genetic diversity, origin of HBV and the Portuguese role in the dissemination of HBV worldwide were never investigated. In this work, we studied the epidemic history and transmission dynamics of HBV genotypes that are endemic in Portugal. HBV pol gene was sequenced from 130 patients followed in Lisbon. HBV genotype A was the most prevalent (n = 54, 41.5%), followed by D (n = 44, 33.8%), and E (n = 32, 24.6%). Spatio-temporal evolutionary dynamics was reconstructed in BEAST using a Bayesian Markov Chain Monte Carlo method, with a GTR nucleotide substitution model, an uncorrelated lognormal relaxed molecular clock model, a Bayesian skyline plot, and a continuous diffusion model. HBV subgenotype D4 was the first to be introduced in Portugal around 1857 (HPD 95% 1699-1931) followed by D3 and A2 a few decades later. HBV genotype E and subgenotype A1 were introduced in Portugal later, almost simultaneously. Our results indicate a very important role of Portugal in the exportation of subgenotypes D4 and A2 to Brazil and Cape Verde, respectively, in the beginning of the XX century. This work clarifies the epidemiological history of HBV in Portugal and provides new insights in the early and global epidemic history of this virus.


Assuntos
Vírus da Hepatite B , Hepatite B , Humanos , Vírus da Hepatite B/genética , Filogeografia , Portugal/epidemiologia , Teorema de Bayes , Filogenia , Genótipo , Hepatite B/epidemiologia , DNA Viral/genética
12.
Microbiol Spectr ; 10(6): e0163422, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36445130

RESUMO

A minority of HIV-1-infected patients produce broadly neutralizing antibodies (bNAbs). Identification of viral and host correlates of bNAb production may help develop vaccines. We aimed to characterize the neutralizing response and viral and host-associated factors in Angola, which has one of the oldest, most dynamic, and most diverse HIV-1 epidemics in the world. Three hundred twenty-two HIV-1-infected adults from Angola were included in this retrospective study. Phylogenetic analysis of C2V3C3 env gene sequences was used for virus subtyping. Env-binding antibody reactivity was tested against polypeptides comprising the C2, V3, and C3 regions. Neutralizing-antibody responses were determined against a reference panel of tier 2 Env pseudoviruses in TZM-bl cells; neutralizing epitope specificities were predicted using ClustVis. All subtypes were found, along with untypeable strains and recombinant forms. Notably, 56% of the patients developed cross neutralizing, broadly neutralizing, or elite neutralizing responses. Broad and elite neutralization was associated with longer infection time, subtype C, lower CD4+ T cell counts, higher age, and higher titer of C2V3C3-specific antibodies relative to failure to develop bNAbs. Neutralizing antibodies targeted the V3-glycan supersite in most patients. V3 and C3 regions were significantly less variable in elite neutralizers than in weak neutralizers and nonneutralizers, suggesting an active role of V3C3-directed bNAbs in controlling HIV-1 replication and diversification. In conclusion, prolonged and low-level envelope V3C3 stimulation by highly diverse and ancestral HIV-1 isolates promotes the frequent elicitation of bNAbs. These results provide important clues for the development of an effective HIV-1 vaccine. IMPORTANCE Studies on neutralization by antibodies and their determinants in HIV-1-infected individuals have mostly been conducted in relatively recent epidemics caused by subtype B and C viruses. Results have suggested that elicitation of broadly neutralizing antibodies (bNAbs) is uncommon. The mechanisms underlying the elicitation of bNAbs are still largely unknown. We performed the first characterization of the plasma neutralizing response in a cohort of HIV-1-infected patients from Angola. Angola is characterized by an old and dynamic epidemic caused by highly diverse HIV-1 variants. Remarkably, more than half of the patients produced bNAbs, mostly targeting the V3-glycan supersite in HIV-1. This was associated with higher age, longer infection time, lower CD4+ T cell counts, subtype C infection, or higher titer of C2V3C3-specific antibodies relative to patients that did not develop bNAbs. These results may help develop the next generation of vaccine candidates for HIV-1.


Assuntos
Infecções por HIV , HIV-1 , Vacinas , Adulto , Humanos , Anticorpos Anti-HIV/genética , Anticorpos Amplamente Neutralizantes/genética , HIV-1/genética , Filogenia , Estudos Retrospectivos , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética , Anticorpos Neutralizantes
13.
Environ Sci Pollut Res Int ; 29(20): 30486-30495, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35000156

RESUMO

Multielement concentrations (P, S, Cl, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Rb, and Rh) and total mercury (T-Hg) were analyzed in different organs and tissues of Amazonian manatee (Trichechus inunguis). Samples of 27 T. inunguis specimens, maintained in the collection of the Amazonian Center for the Research and Preservation of Aquatic Mammals, were used, situated in an area highly impacted by gold mining in the northern region of the Brazilian Amazon. Samples of aquatic plants used as food by the animals were also analyzed. The elements S, Cl, K, Cr, and Mn accumulated mainly in the musculature, while Fe and Cu were more concentrated in the liver. Trace elements, such as rubidium (Rb) and rhodium (Rh), not previously reported in the organs of animals of the family Trichechidae, were also identified. The averages for T-Hg in the skin, muscle, encephalon, liver, kidney, and lung samples were, respectively, 0.1540 ± 0.1332, 0.0593 ± 0.1044, 0.0517 ± 0.0467, 0.0486 ± 0.0543, 0.0237 ± 0.0336, and 0.0013 ± 0.0032 µg.g-1. The values obtained for the vibrissae samples were below the limit of quantification, which allows for the conclusion that this tissue cannot be used as a contamination marker. It was observed that even when kept in a conservation breeding site, these animals were exposed to non-essential trace elements. Differences in the accumulation of elements were observed between the different organs and tissues analyzed. The presence of contaminants in animals that live in a preservation center, even at low levels, deserves attention.


Assuntos
Mercúrio , Oligoelementos , Trichechus inunguis , Animais , Brasil , Mamíferos , Trichechus inunguis/fisiologia
14.
J Virol ; 84(23): 12429-36, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20844029

RESUMO

Human immunodeficiency virus type 2 (HIV-2) infection affects about 1 to 2 million individuals, the majority living in West Africa, Europe, and India. As for HIV-1, new strategies for the prevention of HIV-2 infection are needed. Our aim was to produce new vaccine immunogens that elicit the production of broadly reactive HIV-2 neutralizing antibodies (NAbs). Native and truncated envelope proteins from the reference HIV-2ALI isolate were expressed in vaccinia virus or in bacteria. This source isolate was used due to its unique phenotype combining CD4 independence and CCR5 usage. NAbs were not elicited in BALB/c mice by single immunization with a truncated and fully glycosylated envelope gp125 (gp125t) or a recombinant polypeptide comprising the C2, V3, and C3 envelope regions (rpC2-C3). A strong and broad NAb response was, however, elicited in mice primed with gp125t expressed in vaccinia virus and boosted with rpC2-C3. Serum from these animals potently neutralized (median 50% neutralizing titer, 3,200) six of six highly divergent primary HIV-2 isolates. Coreceptor usage and the V3 sequence of NAb-sensitive isolates were similar to that of the vaccinating immunogen (HIV-2ALI). In contrast, NAbs were not reactive on three X4 isolates that displayed major changes in V3 loop sequence and structure. Collectively, our findings demonstrate that broadly reactive HIV-2 NAbs can be elicited by using a vaccinia virus vector-prime/rpC2-C3-boost immunization strategy and suggest a potential relationship between escape to neutralization and cell tropism.


Assuntos
Anticorpos Neutralizantes/imunologia , Infecções por HIV/prevenção & controle , HIV-2/imunologia , Proteínas Recombinantes/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Animais , Anticorpos Neutralizantes/genética , Primers do DNA/genética , Ensaio de Imunoadsorção Enzimática , Vetores Genéticos/genética , Infecções por HIV/imunologia , Células HeLa , Humanos , Imunização Secundária , Imunoprecipitação , Camundongos , Camundongos Endogâmicos BALB C , Mutagênese , Testes de Neutralização , Proteínas Recombinantes/metabolismo , Vaccinia virus , Produtos do Gene env do Vírus da Imunodeficiência Humana/metabolismo
15.
J Virol ; 84(14): 7412-5, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20463072

RESUMO

The objective of this study was to estimate and compare the evolutionary rates of HIV-2 and HIV-1. Two HIV-2 data sets from patients with advanced disease were compared to matched HIV-1 data sets. The estimated mean evolutionary rate of HIV-2 was significantly higher than the estimated rate of HIV-1, both in the gp125 and in the V3 region of the env gene. In addition, the rate of synonymous substitutions in gp125 was significantly higher for HIV-2 than for HIV-1, possibly indicating a shorter generation time or higher mutation rate of HIV-2. Thus, the lower virulence of HIV-2 does not appear to translate into a lower rate of evolution.


Assuntos
Evolução Molecular , Infecções por HIV/virologia , HIV-1/genética , HIV-2/genética , DNA Viral/genética , Variação Genética , Infecções por HIV/genética , Infecções por HIV/fisiopatologia , HIV-1/patogenicidade , HIV-2/patogenicidade , Humanos , Dados de Sequência Molecular , Mutação , Seleção Genética , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética
16.
Biodivers Data J ; 9: e62157, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33746534

RESUMO

BACKGROUND: In this paper, we present an extensive checklist of selected arthropods and their distribution in five Islands of the Azores (Santa Maria. São Miguel, Terceira, Flores and Pico). Habitat surveys included five herbaceous and four arboreal habitat types, scaling up from native to anthropogenic managed habitats. We aimed to contribute to the ongoing effort to document the terrestrial biodiversity of the world, in particular the Portuguese archipelago of the Azores, as islands harbour a significant portion of unique terrestrial biodiversity. Selection of Arthropoda groups for the current checklist was based on their known richness and abundance (Arachnida, Collembola, Hemiptera, Neuroptera, Coleoptera, Hymenoptera), in almost all terrestrial ecosystems, as well as their importance in current Integrated Pest Management and alternative Biocontrol protocols at large (i.e. hymenopteran parasitoids and beneficial Coleoptera). In addition, we include the list of Dermaptera, Orthoptera, Psocoptera and Thysanoptera species. These assembled groups represent part of the monitoring programme EDEN Azores (2008-2014), where all Arthropod fauna, at all strata, within nine representative habitats of the abovementioned five Islands of the Azores was recorded. NEW INFORMATION: In this study, a total of 116,523 specimens, belonging to 483 species and subspecies of selected groups of arthropods, are reported by order, family and, when possible, genus and species. Hymenopteran, mostly parasitoids, accounted for the most represented taxa across all the monitoring and sampling phase of EDEN Azores (193 species and mophospecies), followed by Coleoptera (95 species); Collembola (89 species); and Araneae (72 species).A total of 37 non-native species are reported for the first time in the Azores. Coleoptera: Asaphidion flavipes (Linnaeus, 1761) (Carabidae); Tachyporus dispar (Paykull, 1789) (Staphylinidae). Hemiptera: Acrosternum heegeri Fieber, 1861 (Pentatomidae). Collembola: Entomobrya regularis Stach, 1963 (Entomobryidae); Lepidocyrtus lusitanicus piezoensis (Simón-Benito, 2007) (Entomobryidae); Jordanathrix articulata (Ellis, 1974) (Sminthuridae); Sminthurinus quadrimaculatus (Ryder, 1879) (Katiannidae); Himalanura sp. (Entomobryidae); Protophorura sp. (Onychiuridae). Hymenoptera, parasitoids: Aphidius colemani Viereck, 1912 (Braconidae); Aphidius ervi Haliday, 1834 (Braconidae); Aphidius matricariae Viereck, 1912 (Braconidae); Aphidius rhopalosiphi Stefani-Perez, 1902 (Braconidae); Aphidius rosae (Haliday, 1834) (Braconidae); Aphidius urticae Haliday, 1834 (Braconidae); Centistidea ectoedemiae Rohwer, 1914 (Braconidae); Meteorus unicolor (Wesmael, 1835) (Braconidae); Meteorus collaris (Spin.) Hal. - Ruschka, Fulmek, 1915 (Braconidae); Orthostigma cratospilum (Thomson, 1895) (Braconidae); Orthostigma latriventris Ratzeburg, 1844 (Braconidae); two other species of Orthostigma sp.; Pseudopezomachus bituberculatus (Marshall, 1905) (Braconidae); Tanycarpa punctata (van Achterberg, 1976) (Braconidae); Gonatopus clavipes (Thunberg, 1827) (Dryinidae). New genera not previously recorded for the Azores include: Pycnetron sp. (Chalcidoidea: Pteromalidae); four species of Aspilota sp. (Braconidae: Alysiinae); four species of Chorebus sp. (Braconidae: Aphidiinae: Alysiinae); Microgaster sp. (Braconidae: Microgastrinae); Homolobus sp. (Braconidae: Homolobinae); Lodbrokia sp. (Braconidae: Alysiinae).These 37 taxa were found in several Islands and five are new species for Flores Island, 10 species are new for Pico Island, 12 species are new for Terceira Island, 19 species are new for S. Miguel Island and five species are new for S. Maria Island.Additional species records for the Islands included: Flores (5 Collembola, 9 Araneae; 2 Hemiptera; 8 Coleoptera, 8 Hymenoptera), Pico (4 Collembola; 7 Araneae; 4 Hemiptera; 11 Coleoptera; 9 Hymenoptera), Terceira (4 Collembola; 1 Araneae; 3 Hymenoptera), S. Miguel (1 Araneae; 2 Coleoptera; 3 Hymenoptera), S. Maria (5 Collembola; 3 Araneae; 2 Hemiptera; 2 Hymenoptera).

17.
Sci Rep ; 11(1): 8993, 2021 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-33903642

RESUMO

The ectodomain of gp41 is the target of potent binding and neutralizing antibodies (NAbs) and is being explored in new strategies for antibody-based HIV vaccines. Previous studies have suggested that the W164A-3S (3S) and EC26-2A4 (EC26) peptides located in the gp41 ectodomain may be potential HIV vaccine candidates. We assessed 3S- and EC26-specific binding antibody responses and related neutralizing activity in a large panel of chronic HIV-1-infected Portuguese individuals on ART. A similar proportion of participants had antibodies binding to 3S (9.6%) and EC26 (9.9%) peptides but the level of reactivity against 3S was significantly higher compared to EC26, except in the rare patients with double peptide reactivity. The higher antigenicity of 3S was unrelated with disease stage, as assessed by CD4+ T cell counts, but it was directly related with plasma viral load. Most patients that were tested (89.9%, N = 268) showed tier 1 neutralizing activity, the potency being inversely associated with plasma viral load. In the subset of patients that were tested for neutralization of tier 2 isolates, neutralization breadth was inversely correlated with plasma viral load and directly correlated with CD4+ T cell counts. These results are consistent with a role for neutralizing antibodies in controlling viral replication and preventing the decline of CD4+ T lymphocytes. Importantly, in patients with 3S-specific antibodies, neutralizing titers were inversely correlated with viral RNA levels and proviral DNA levels. Moreover, patients with 3S and/or EC26-specific antibodies showed a 1.9-fold higher tier 2 neutralization score than patients without antibodies suggesting that 3S and/or EC26-specific antibodies contribute to neutralization breadth and potency in HIV-1 infected patients. Overall, these results suggest that antibodies targeting the S3 and EC26 epitopes may contribute to reduce viral burden and provide further support for the inclusion of 3S and EC26 epitopes in HIV-1 vaccine candidates.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Epitopos/imunologia , Anticorpos Anti-HIV/imunologia , Proteína gp41 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Contagem de Linfócito CD4 , Humanos , Carga Viral
18.
Vaccines (Basel) ; 8(2)2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32272637

RESUMO

Development of new immunogens eliciting broadly neutralizing antibodies (bNAbs) is a main priority for the HIV-1 vaccine field. Envelope glycoproteins from non-B-non-C HIV-1clades have not been fully explored as components of a vaccine. We produced Vaccinia viruses expressing a truncated version of gp120 (gp120t) from HIV-1 clades CRF02_AG, H, J, B, and C and examined their immunogenicity in mice and rabbits. Mice primed with the recombinant Vaccinia viruses and boosted with the homologous gp120t or C2V3C3 polypeptides developed antibodies that bind potently to homologous and heterologous envelope glycoproteins. Notably, a subset of mice immunized with the CRF02_AG-based envelope immunogens developed a cross-reactive neutralizing response against tier 2 HIV-1 Env-pseudoviruses and primary isolates. Rabbits vaccinated with the CRF02_AG-based envelope immunogens also generated potent binding antibodies, and one animal elicited antibodies that neutralized almost all (13 of 16, 81.3%) tier 2 HIV-1 isolates tested. Overall, the results suggest that the novel CRF02_AG-based envelope immunogens and prime-boost immunization strategy elicit the type of immune responses required for a preventive HIV-1 vaccine.

19.
Insect Biochem Mol Biol ; 120: 103334, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32109587

RESUMO

The soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae) is a serious pest of the soybean plant, Glycine max, a major world-wide agricultural crop. We assembled a de novo genome sequence of Ap. glycines Biotype 1, from a culture established shortly after this species invaded North America. 20.4% of the Ap. glycines proteome is duplicated. These in-paralogs are enriched with Gene Ontology (GO) categories mostly related to apoptosis, a possible adaptation to plant chemistry and other environmental stressors. Approximately one-third of these genes show parallel duplication in other aphids. But Ap. gossypii, its closest related species, has the lowest number of these duplicated genes. An Illumina GoldenGate assay of 2380 SNPs was used to determine the world-wide population structure of Ap. Glycines. China and South Korean aphids are the closest to those in North America. China is the likely origin of other Asian aphid populations. The most distantly related aphids to those in North America are from Australia. The diversity of Ap. glycines in North America has decreased over time since its arrival. The genetic diversity of Ap. glycines North American population sampled shortly after its first detection in 2001 up to 2012 does not appear to correlate with geography. However, aphids collected on soybean Rag experimental varieties in Minnesota (MN), Iowa (IA), and Wisconsin (WI), closer to high density Rhamnus cathartica stands, appear to have higher capacity to colonize resistant soybean plants than aphids sampled in Ohio (OH), North Dakota (ND), and South Dakota (SD). Samples from the former states have SNP alleles with high FST values and frequencies, that overlap with genes involved in iron metabolism, a crucial metabolic pathway that may be affected by the Rag-associated soybean plant response. The Ap. glycines Biotype 1 genome will provide needed information for future analyses of mechanisms of aphid virulence and pesticide resistance as well as facilitate comparative analyses between aphids with differing natural history and host plant range.


Assuntos
Adaptação Biológica , Afídeos/genética , Evolução Biológica , Ecótipo , Genoma de Inseto , Espécies Introduzidas , Alelos , Animais , Polimorfismo de Nucleotídeo Único , Estados Unidos
20.
J Insect Sci ; 9: 13, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19613442

RESUMO

A fungal epizootic in populations of Fiorinia externa Ferris (Hemiptera: Diaspididae) infesting hemlock trees, Tsuga canadensis (L.) Carrière (Pinales: Pinaceae) in forests of the Northeastern US has been recently detected. The current known distribution of the epizootic spans 36 sites in New York, Pennsylvania, New Jersey and Connecticut. Colletotrichum acutatum Simmonds var. fioriniae Marcelino and Gouli var. nov. inedit. (Phyllachorales: Phyllachoraceae) was the most prevalent fungus recovered from infected scales. Bioassays indicated that this C. acutatum variety is highly pathogenic to F. externa. Mortality rates of >90 and >55% were obtained for F. externa crawlers and settlers, respectively. Significantly lower mortality levels,

Assuntos
Colletotrichum/patogenicidade , Hemípteros/microbiologia , Insetos/microbiologia , Animais , Colletotrichum/isolamento & purificação , Hemípteros/crescimento & desenvolvimento , Insetos/crescimento & desenvolvimento , Tsuga/parasitologia
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