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1.
Emerg Microbes Infect ; 13(1): 2294860, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38165394

RESUMO

COVID-19 remains a major public health concern. Monoclonal antibodies have received emergency use authorization (EUA) for pre-exposure prophylaxis against COVID-19 among high-risk groups for treatment of mild to moderate COVID-19. In addition to recombinant biologics, engineered synthetic DNA-encoded antibodies (DMAb) are an important strategy for direct in vivo delivery of protective mAb. A DMAb cocktail was synthetically engineered to encode the immunoglobulin heavy and light chains of two different two different Fc-engineered anti-SARS-CoV-2 antibodies. The DMAbs were designed to enhance in vivo expression and delivered intramuscularly to cynomolgus and rhesus macaques with a modified in vivo delivery regimen. Serum levels were detected in macaques, along with specific binding to SARS-CoV-2 spike receptor binding domain protein and neutralization of multiple SARS-CoV-2 variants of concern in pseudovirus and authentic live virus assays. Prophylactic administration was protective in rhesus macaques against signs of SARS-CoV-2 (USA-WA1/2020) associated disease in the lungs. Overall, the data support further study of DNA-encoded antibodies as an additional delivery mode for prevention of COVID-19 severe disease. These data have implications for human translation of gene-encoded mAbs for emerging infectious diseases and low dose mAb delivery against COVID-19.


Assuntos
COVID-19 , Profilaxia Pré-Exposição , Animais , Macaca mulatta , COVID-19/prevenção & controle , SARS-CoV-2/genética , Anticorpos Antivirais , Anticorpos Monoclonais , Macaca fascicularis , DNA , Anticorpos Neutralizantes , Glicoproteína da Espícula de Coronavírus/genética
2.
Curr Med Res Opin ; 40(1): 3-4, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38073080
3.
Curr Med Res Opin ; 40(1): 5-7, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37791596

RESUMO

[Figure: see text].


Assuntos
Inteligência Artificial , Atenção à Saúde , Humanos
5.
Mol Phylogenet Evol ; 184: 107778, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37030415

RESUMO

Leaf-mining flies (Diptera: Agromyzidae) are a diverse clade of phytophagous Diptera known largely for their economic impact as leaf- or stem-miners on vegetable and ornamental plants. Higher-level phylogenetic relationships of Agromyzidae have remained uncertain because of challenges in sampling of both taxa and characters for morphology and PCR-based Sanger-era molecular systematics. Here, we used hundreds of orthologous single-copy nuclear loci obtained from anchored hybrid enrichment (AHE) to reconstruct phylogenetic relationships among the major lineages of leaf-mining flies. The resulting phylogenetic trees are highly congruent and well-supported, except for a few deep nodes, when using different molecular data types and phylogenetic methods. Based on divergence time dating using a relaxed clock model-based analysis, leaf-mining flies are shown to have diversified in multiple lineages since the early Paleocene, approximately 65 million years ago. Our study not only reveals a revised classification system of leaf-mining flies, but also provides a new phylogenetic framework to understand their macroevolution.


Assuntos
Dípteros , Filogenia , Genômica , Dípteros/genética , Animais , Funções Verossimilhança , Loci Gênicos
7.
JCI Insight ; 8(4)2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36574296

RESUMO

The periodic emergence of SARS-CoV-2 variants of concern (VOCs) with unpredictable clinical severity and ability to escape preexisting immunity emphasizes the continued need for antiviral interventions. Two small molecule inhibitors, molnupiravir (MK-4482), a nucleoside analog, and nirmatrelvir (PF-07321332), a 3C-like protease inhibitor, have recently been approved as monotherapy for use in high-risk patients with COVID-19. As preclinical data are only available for rodent and ferret models, here we assessed the efficacy of MK-4482 and PF-07321332 alone and in combination against infection with the SARS-CoV-2 Delta VOC in the rhesus macaque COVID-19 model. Macaques were infected with the SARS-CoV-2 Delta variant and treated with vehicle, MK-4482, PF-07321332, or a combination of MK-4482 and PF-07321332. Clinical exams were performed at 1, 2, and 4 days postinfection to assess disease and virological parameters. Notably, use of MK-4482 and PF-07321332 in combination improved the individual inhibitory effect of both drugs, resulting in milder disease progression, stronger reduction of virus shedding from mucosal tissues of the upper respiratory tract, stronger reduction of viral replication in the lower respiratory tract, and reduced lung pathology. Our data strongly indicate superiority of combined MK-4482 and PF-07321332 treatment of SARS-CoV-2 infections as demonstrated in the closest COVID-19 surrogate model of human infection.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Humanos , Macaca mulatta , Furões , Lactamas , Leucina , Nitrilas , Antivirais
8.
bioRxiv ; 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36263071

RESUMO

The periodic emergence of SARS-CoV-2 variants of concern (VOCs) with unpredictable clinical severity and ability to escape preexisting immunity emphasizes the continued need for antiviral interventions. Two small molecule inhibitors, molnupiravir (MK-4482), a nucleoside analog, and nirmatrelvir (PF-07321332), a 3C-like protease inhibitor, have each recently been approved as monotherapy for use in high risk COVID-19 patients. As preclinical data are only available for rodent and ferret models, we originally assessed the efficacy of MK-4482 and PF-07321332 alone and then in combination Against infection with the SARS-CoV-2 Delta VOC in the rhesus macaque COVID-19 model. Notably, use of MK-4482 and PF-07321332 in combination improved the individual inhibitory effect of both drugs. Combined treatment resulted in milder disease progression, stronger reduction of virus shedding from mucosal tissues of the upper respiratory tract, stronger reduction of viral replication in the lower respiratory tract, and reduced lung pathology. Our data strongly indicate superiority of combined MK-4482 and PF-07321332 treatment of SARS-CoV-2 infections as demonstrated here in the closest COVID-19 surrogate model. One Sentence Summary: The combination of molnupiravir and nirmatrelvir inhibits SARS-CoV-2 replication and shedding more effectively than individual treatments in the rhesus macaque model.

9.
Sci Total Environ ; 841: 156704, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35718174

RESUMO

Southeast Asia is considered to have some of the highest levels of marine plastic pollution in the world. It is therefore vitally important to increase our understanding of the impacts and risks of plastic pollution to marine ecosystems and the essential services they provide to support the development of mitigation measures in the region. An interdisciplinary, international network of experts (Australia, Indonesia, Ireland, Malaysia, the Philippines, Singapore, Thailand, the United Kingdom, and Vietnam) set a research agenda for marine plastic pollution in the region, synthesizing current knowledge and highlighting areas for further research in Southeast Asia. Using an inductive method, 21 research questions emerged under five non-predefined key themes, grouping them according to which: (1) characterise marine plastic pollution in Southeast Asia; (2) explore its movement and fate across the region; (3) describe the biological and chemical modifications marine plastic pollution undergoes; (4) detail its environmental, social, and economic impacts; and, finally, (5) target regional policies and possible solutions. Questions relating to these research priority areas highlight the importance of better understanding the fate of marine plastic pollution, its degradation, and the impacts and risks it can generate across communities and different ecosystem services. Knowledge of these aspects will help support actions which currently suffer from transboundary problems, lack of responsibility, and inaction to tackle the issue from its point source in the region. Being profoundly affected by marine plastic pollution, Southeast Asian countries provide an opportunity to test the effectiveness of innovative and socially inclusive changes in marine plastic governance, as well as both high and low-tech solutions, which can offer insights and actionable models to the rest of the world.


Assuntos
Ecossistema , Plásticos , Sudeste Asiático , Monitoramento Ambiental , Poluição Ambiental , Filipinas , Resíduos/análise
10.
Anal Chem ; 89(6): 3300-3309, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28240543

RESUMO

A major purpose of exploratory metabolic profiling is for the identification of molecular species that are statistically associated with specific biological or medical outcomes; unfortunately, the structure elucidation process of unknowns is often a major bottleneck in this process. We present here new holistic strategies that combine different statistical spectroscopic and analytical techniques to improve and simplify the process of metabolite identification. We exemplify these strategies using study data collected as part of a dietary intervention to improve health and which elicits a relatively subtle suite of changes from complex molecular profiles. We identify three new dietary biomarkers related to the consumption of peas (N-methyl nicotinic acid), apples (rhamnitol), and onions (N-acetyl-S-(1Z)-propenyl-cysteine-sulfoxide) that can be used to enhance dietary assessment and assess adherence to diet. As part of the strategy, we introduce a new probabilistic statistical spectroscopy tool, RED-STORM (Resolution EnhanceD SubseT Optimization by Reference Matching), that uses 2D J-resolved 1H NMR spectra for enhanced information recovery using the Bayesian paradigm to extract a subset of spectra with similar spectral signatures to a reference. RED-STORM provided new information for subsequent experiments (e.g., 2D-NMR spectroscopy, solid-phase extraction, liquid chromatography prefaced mass spectrometry) used to ultimately identify an unknown compound. In summary, we illustrate the benefit of acquiring J-resolved experiments alongside conventional 1D 1H NMR as part of routine metabolic profiling in large data sets and show that application of complementary statistical and analytical techniques for the identification of unknown metabolites can be used to save valuable time and resources.


Assuntos
Malus/metabolismo , Ácidos Nicotínicos/análise , Cebolas/metabolismo , Pisum sativum/metabolismo , Ramnose/análise , Biomarcadores/análise , Biomarcadores/metabolismo , Espectroscopia de Ressonância Magnética , Malus/química , Estrutura Molecular , Ácidos Nicotínicos/metabolismo , Cebolas/química , Pisum sativum/química , Ramnose/análogos & derivados , Ramnose/metabolismo
11.
Form Methods Syst Des ; 47: 75-92, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26900259

RESUMO

Many software model checkers only detect counterexamples with deep loops after exploring numerous spurious and increasingly longer counterexamples. We propose a technique that aims at eliminating this weakness by constructing auxiliary paths that represent the effect of a range of loop iterations. Unlike acceleration, which captures the exact effect of arbitrarily many loop iterations, these auxiliary paths may under-approximate the behaviour of the loops. In return, the approximation is sound with respect to the bit-vector semantics of programs. Our approach supports arbitrary conditions and assignments to arrays in the loop body, but may as a result introduce quantified conditionals. To reduce the resulting performance penalty, we present two quantifier elimination techniques specially geared towards our application. Loop under-approximation can be combined with a broad range of verification techniques. We paired our techniques with lazy abstraction and bounded model checking, and evaluated the resulting tool on a number of buffer overflow benchmarks, demonstrating its ability to efficiently detect deep counterexamples in C programs that manipulate arrays.

12.
Appl Environ Microbiol ; 77(4): 1512-5, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21183639

RESUMO

The functional metagenomic screening of the microbial communities associated with a temperate marine sponge and a green alga identified three novel hydrolytic enzymes with antibacterial activities. The results suggest that uncultured alpha- and gammaproteobacteria contain new classes of proteins that may be a source of antibacterial agents.


Assuntos
Alphaproteobacteria/enzimologia , Antibacterianos/biossíntese , Gammaproteobacteria/enzimologia , Poríferos/microbiologia , Ulva/microbiologia , Animais , Elementos de DNA Transponíveis , Metagenômica , Consórcios Microbianos/genética , Mutação
13.
ISME J ; 5(4): 590-600, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21048801

RESUMO

Green Ulvacean marine macroalgae are distributed worldwide in coastal tidal and subtidal ecosystems. As for many living surfaces in the marine environment, little is known concerning the epiphytic bacterial biofilm communities that inhabit algal surfaces. This study reports on the largest published libraries of near full-length 16S rRNA genes from a marine algal surface (5293 sequences from six samples) allowing for an in-depth assessment of the diversity and phylogenetic profile of the bacterial community on a green Ulvacean alga. Large 16S rRNA gene libraries of surrounding seawater were also used to determine the uniqueness of this bacterial community. The surface of Ulva australis is dominated by sequences of Alphaproteobacteria and the Bacteroidetes, especially within the Rhodobacteriaceae, Sphingomonadaceae, Flavobacteriaceae and Sapropiraceae families. Seawater libraries were also dominated by Alphaproteobacteria and Bacteroidetes sequences, but were shown to be clearly distinct from U. australis libraries through the clustering of sequences into operational taxonomic units and Bray-Curtis similarity analysis. Almost no similarity was observed between these two environments at the species level, and only minor similarity was observed at levels of sequence clustering representing clades of bacteria within family and genus taxonomic groups. Variability between libraries of U. australis was relatively high, and a consistent sub-population of bacterial species was not detected. The competitive lottery model, originally derived to explain diversity in coral reef fishes, may explain the pattern of colonization of this algal surface.


Assuntos
Bactérias/classificação , Ulva/microbiologia , Alphaproteobacteria/classificação , Alphaproteobacteria/genética , Alphaproteobacteria/isolamento & purificação , Bactérias/genética , Bactérias/isolamento & purificação , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Ecossistema , Filogenia , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Análise de Sequência de DNA
14.
ISME J ; 4(12): 1557-67, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20520651

RESUMO

Sponges form close relationships with bacteria, and a remarkable phylogenetic diversity of yet-uncultured bacteria has been identified from sponges using molecular methods. In this study, we use a comparative metagenomic analysis of the bacterial community in the model sponge Cymbastela concentrica and in the surrounding seawater to identify previously unrecognized genomic signatures and functions for sponge bacteria. We observed a surprisingly large number of transposable insertion elements, a feature also observed in other symbiotic bacteria, as well as a set of predicted mechanisms that may defend the sponge community against the introduction of foreign DNA and hence contribute to its genetic resilience. Moreover, several shared metabolic interactions between bacteria and host include vitamin production, nutrient transport and utilization, and redox sensing and response. Finally, an abundance of protein-protein interactions mediated through ankyrin and tetratricopeptide repeat proteins could represent a mechanism for the sponge to discriminate between food and resident bacteria. These data provide new insight into the evolution of symbiotic diversity, microbial metabolism and host-microbe interactions in sponges.


Assuntos
Bactérias/genética , Filogenia , Poríferos/microbiologia , Água do Mar/microbiologia , Simbiose , Animais , Bactérias/classificação , Bactérias/metabolismo , Evolução Biológica , Hibridização Genômica Comparativa , Elementos de DNA Transponíveis , DNA Bacteriano/genética , Ecossistema , Genoma Bacteriano , Metagenoma , Poríferos/fisiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
15.
ISME J ; 4(8): 1002-19, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20237513

RESUMO

Green sulfur bacteria (GSB) (Chlorobiaceae) are primary producers that are important in global carbon and sulfur cycling in natural environments. An almost complete genome sequence for a single, dominant GSB species ('C-Ace') was assembled from shotgun sequence data of an environmental sample taken from the O(2)-H(2)S interface of the water column of Ace Lake, Antarctica. Approximately 34 Mb of DNA sequence data were assembled into nine scaffolds totaling 1.79 Mb, representing approximately 19-fold coverage for the C-Ace composite genome. A high level ( approximately 31%) of metaproteomic coverage was achieved using matched biomass. The metaproteogenomic approach provided unique insight into the protein complement required for dominating the microbial community under cold, nutrient-limited, oxygen-limited and extremely varied annual light conditions. C-Ace shows physiological traits that promote its ability to compete very effectively with other GSB and gain dominance (for example, specific bacteriochlorophylls, mechanisms of cold adaptation) as well as a syntrophic relationship with sulfate-reducing bacteria that provides a mechanism for the exchange of sulfur compounds. As a result we are able to propose an explanation of the active biological processes promoted by cold-adapted GSB and the adaptive strategies they use to thrive under the severe physiochemical conditions prevailing in polar environments.


Assuntos
Chlorobi/genética , Chlorobi/metabolismo , Água Doce/microbiologia , Metagenômica , Proteômica , Enxofre/metabolismo , Regiões Antárticas , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Chlorobi/isolamento & purificação , Dados de Sequência Molecular
16.
Nucleic Acids Res ; 37(21): e144, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19767618

RESUMO

Metagenomics provides access to the uncultured majority of the microbial world. The approaches employed in this field have, however, had limited success in linking functional genes to the taxonomic or phylogenetic origin of the organism they belong to. Here we present an efficient strategy to recover environmental DNA fragments that contain phylogenetic marker genes from metagenomic libraries. Our method involves the cleavage of 23S ribsosmal RNA (rRNA) genes within pooled library clones by the homing endonuclease I-CeuI followed by the insertion and selection of an antibiotic resistance cassette. This approach was applied to screen a library of 6500 fosmid clones derived from the microbial community associated with the sponge Cymbastela concentrica. Several fosmid clones were recovered after the screen and detailed phylogenetic and taxonomic assignment based on the rRNA gene showed that they belong to previously unknown organisms. In addition, compositional features of these fosmid clones were used to classify and taxonomically assign a dataset of environmental shotgun sequences. Our approach represents a valuable tool for the analysis of rapidly increasing, environmental DNA sequencing information.


Assuntos
Bactérias/classificação , Endodesoxirribonucleases , Genoma Bacteriano , Biblioteca Genômica , Metagenômica/métodos , Filogenia , Animais , Sequência de Bases , Enzimas de Restrição do DNA , Genes de RNAr , Marcadores Genéticos , Dados de Sequência Molecular , Poríferos/microbiologia , RNA Ribossômico 23S/genética
17.
J Arthroplasty ; 24(7): 1130-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18757169

RESUMO

Weakness of the hip abductors after total hip arthroplasty may result in pain and/or functional limitation. Non-weight-bearing (NWB) exercises are often performed to target the hip abductors; however, muscle activation of NWB exercises has not been compared to weight-bearing (WB) exercises. Our purpose was to evaluate gluteus medius activation during 2 WB and 2 NWB hip abductor strengthening exercises. Fifteen patients at least 6 weeks post unilateral total hip arthroplasty volunteered for the study. Electromyographic amplitude for each exercise was normalized to each patient's maximal voluntary isometric contraction. There were no significant differences in gluteus medius electromyographic amplitudes between the 4 exercises (P = .15). Based on our results, NWB exercises provided no clear benefit in terms of gluteus medius activation when compared to potentially more functional WB exercises in the early postoperative period.


Assuntos
Artroplastia de Quadril , Exercício Físico/fisiologia , Articulação do Quadril/fisiologia , Contração Isométrica/fisiologia , Músculo Esquelético/fisiologia , Idoso , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Quadril/cirurgia , Período Pós-Operatório , Treinamento Resistido , Suporte de Carga/fisiologia
18.
Nature ; 432(7019): 910-3, 2004 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-15602564

RESUMO

Since the recognition of prokaryotes as essential components of the oceanic food web, bacterioplankton have been acknowledged as catalysts of most major biogeochemical processes in the sea. Studying heterotrophic bacterioplankton has been challenging, however, as most major clades have never been cultured or have only been grown to low densities in sea water. Here we describe the genome sequence of Silicibacter pomeroyi, a member of the marine Roseobacter clade (Fig. 1), the relatives of which comprise approximately 10-20% of coastal and oceanic mixed-layer bacterioplankton. This first genome sequence from any major heterotrophic clade consists of a chromosome (4,109,442 base pairs) and megaplasmid (491,611 base pairs). Genome analysis indicates that this organism relies upon a lithoheterotrophic strategy that uses inorganic compounds (carbon monoxide and sulphide) to supplement heterotrophy. Silicibacter pomeroyi also has genes advantageous for associations with plankton and suspended particles, including genes for uptake of algal-derived compounds, use of metabolites from reducing microzones, rapid growth and cell-density-dependent regulation. This bacterium has a physiology distinct from that of marine oligotrophs, adding a new strategy to the recognized repertoire for coping with a nutrient-poor ocean.


Assuntos
Adaptação Fisiológica/genética , Genoma Bacteriano , Plâncton/genética , Plâncton/fisiologia , Roseobacter/genética , Roseobacter/fisiologia , Água do Mar/microbiologia , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Genes Bacterianos/genética , Biologia Marinha , Dados de Sequência Molecular , Oceanos e Mares , Filogenia , Plâncton/classificação , RNA Ribossômico 16S/genética , Roseobacter/classificação
19.
PLoS Biol ; 2(10): e303, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15383840

RESUMO

Methanotrophs are ubiquitous bacteria that can use the greenhouse gas methane as a sole carbon and energy source for growth, thus playing major roles in global carbon cycles, and in particular, substantially reducing emissions of biologically generated methane to the atmosphere. Despite their importance, and in contrast to organisms that play roles in other major parts of the carbon cycle such as photosynthesis, no genome-level studies have been published on the biology of methanotrophs. We report the first complete genome sequence to our knowledge from an obligate methanotroph, Methylococcus capsulatus (Bath), obtained by the shotgun sequencing approach. Analysis revealed a 3.3-Mb genome highly specialized for a methanotrophic lifestyle, including redundant pathways predicted to be involved in methanotrophy and duplicated genes for essential enzymes such as the methane monooxygenases. We used phylogenomic analysis, gene order information, and comparative analysis with the partially sequenced methylotroph Methylobacterium extorquens to detect genes of unknown function likely to be involved in methanotrophy and methylotrophy. Genome analysis suggests the ability of M. capsulatus to scavenge copper (including a previously unreported nonribosomal peptide synthetase) and to use copper in regulation of methanotrophy, but the exact regulatory mechanisms remain unclear. One of the most surprising outcomes of the project is evidence suggesting the existence of previously unsuspected metabolic flexibility in M. capsulatus, including an ability to grow on sugars, oxidize chemolithotrophic hydrogen and sulfur, and live under reduced oxygen tension, all of which have implications for methanotroph ecology. The availability of the complete genome of M. capsulatus (Bath) deepens our understanding of methanotroph biology and its relationship to global carbon cycles. We have gained evidence for greater metabolic flexibility than was previously known, and for genetic components that may have biotechnological potential.


Assuntos
Regulação Bacteriana da Expressão Gênica , Genoma , Metano/metabolismo , Methylococcus capsulatus/genética , Proteínas de Bactérias/química , Carbono/química , Transporte de Elétrons , Ácidos Graxos/química , Genoma Bacteriano , Genômica/métodos , Metano/química , Modelos Biológicos , Dados de Sequência Molecular , Nitrogênio/química , Oxigênio/química , Oxigênio/metabolismo , Peptídeos/química , Filogenia , Análise de Sequência de DNA
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