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1.
Cell ; 187(8): 1971-1989.e16, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38521060

RESUMO

Amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) share many clinical, pathological, and genetic features, but a detailed understanding of their associated transcriptional alterations across vulnerable cortical cell types is lacking. Here, we report a high-resolution, comparative single-cell molecular atlas of the human primary motor and dorsolateral prefrontal cortices and their transcriptional alterations in sporadic and familial ALS and FTLD. By integrating transcriptional and genetic information, we identify known and previously unidentified vulnerable populations in cortical layer 5 and show that ALS- and FTLD-implicated motor and spindle neurons possess a virtually indistinguishable molecular identity. We implicate potential disease mechanisms affecting these cell types as well as non-neuronal drivers of pathogenesis. Finally, we show that neuron loss in cortical layer 5 tracks more closely with transcriptional identity rather than cellular morphology and extends beyond previously reported vulnerable cell types.


Assuntos
Esclerose Lateral Amiotrófica , Degeneração Lobar Frontotemporal , Córtex Pré-Frontal , Animais , Humanos , Camundongos , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Demência Frontotemporal/genética , Degeneração Lobar Frontotemporal/genética , Degeneração Lobar Frontotemporal/metabolismo , Degeneração Lobar Frontotemporal/patologia , Perfilação da Expressão Gênica , Neurônios/metabolismo , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/patologia , Análise da Expressão Gênica de Célula Única
2.
Nature ; 619(7970): 650-657, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37344587

RESUMO

Homologous recombination is a fundamental process of life. It is required for the protection and restart of broken replication forks, the repair of chromosome breaks and the exchange of genetic material during meiosis. Individuals with mutations in key recombination genes, such as BRCA2 (also known as FANCD1), or the RAD51 paralogues RAD51B, RAD51C (also known as FANCO), RAD51D, XRCC2 (also known as FANCU) and XRCC3, are predisposed to breast, ovarian and prostate cancers1-10 and the cancer-prone syndrome Fanconi anaemia11-13. The BRCA2 tumour suppressor protein-the product of BRCA2-is well characterized, but the cellular functions of the RAD51 paralogues remain unclear. Genetic knockouts display growth defects, reduced RAD51 focus formation, spontaneous chromosome abnormalities, sensitivity to PARP inhibitors and replication fork defects14,15, but the precise molecular roles of RAD51 paralogues in fork stability, DNA repair and cancer avoidance remain unknown. Here we used cryo-electron microscopy, AlphaFold2 modelling and structural proteomics to determine the structure of the RAD51B-RAD51C-RAD51D-XRCC2 complex (BCDX2), revealing that RAD51C-RAD51D-XRCC2 mimics three RAD51 protomers aligned within a nucleoprotein filament, whereas RAD51B is highly dynamic. Biochemical and single-molecule analyses showed that BCDX2 stimulates the nucleation and extension of RAD51 filaments-which are essential for recombinational DNA repair-in reactions that depend on the coupled ATPase activities of RAD51B and RAD51C. Our studies demonstrate that BCDX2 orchestrates RAD51 assembly on single stranded DNA for replication fork protection and double strand break repair, in reactions that are critical for tumour avoidance.


Assuntos
Microscopia Crioeletrônica , Proteínas de Ligação a DNA , Complexos Multiproteicos , Rad51 Recombinase , Proteínas Supressoras de Tumor , Humanos , Reparo do DNA , Replicação do DNA , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/ultraestrutura , Recombinação Homóloga , Rad51 Recombinase/química , Rad51 Recombinase/metabolismo , Rad51 Recombinase/ultraestrutura , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/metabolismo , Proteínas Supressoras de Tumor/ultraestrutura , Inibidores de Poli(ADP-Ribose) Polimerases , Neoplasias/genética , Neoplasias/prevenção & controle , Proteômica , Simulação por Computador , Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo , Complexos Multiproteicos/ultraestrutura , Quebras de DNA de Cadeia Dupla
3.
Nature ; 580(7802): 245-251, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32269342

RESUMO

Radiologic screening of high-risk adults reduces lung-cancer-related mortality1,2; however, a small minority of eligible individuals undergo such screening in the United States3,4. The availability of blood-based tests could increase screening uptake. Here we introduce improvements to cancer personalized profiling by deep sequencing (CAPP-Seq)5, a method for the analysis of circulating tumour DNA (ctDNA), to better facilitate screening applications. We show that, although levels are very low in early-stage lung cancers, ctDNA is present prior to treatment in most patients and its presence is strongly prognostic. We also find that the majority of somatic mutations in the cell-free DNA (cfDNA) of patients with lung cancer and of risk-matched controls reflect clonal haematopoiesis and are non-recurrent. Compared with tumour-derived mutations, clonal haematopoiesis mutations occur on longer cfDNA fragments and lack mutational signatures that are associated with tobacco smoking. Integrating these findings with other molecular features, we develop and prospectively validate a machine-learning method termed 'lung cancer likelihood in plasma' (Lung-CLiP), which can robustly discriminate early-stage lung cancer patients from risk-matched controls. This approach achieves performance similar to that of tumour-informed ctDNA detection and enables tuning of assay specificity in order to facilitate distinct clinical applications. Our findings establish the potential of cfDNA for lung cancer screening and highlight the importance of risk-matching cases and controls in cfDNA-based screening studies.


Assuntos
DNA Tumoral Circulante/análise , DNA Tumoral Circulante/genética , Detecção Precoce de Câncer/métodos , Genoma Humano/genética , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Mutação , Estudos de Coortes , Feminino , Hematopoese/genética , Humanos , Pulmão/metabolismo , Pulmão/patologia , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
4.
Nucleic Acids Res ; 52(D1): D938-D949, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38000386

RESUMO

Bridging the gap between genetic variations, environmental determinants, and phenotypic outcomes is critical for supporting clinical diagnosis and understanding mechanisms of diseases. It requires integrating open data at a global scale. The Monarch Initiative advances these goals by developing open ontologies, semantic data models, and knowledge graphs for translational research. The Monarch App is an integrated platform combining data about genes, phenotypes, and diseases across species. Monarch's APIs enable access to carefully curated datasets and advanced analysis tools that support the understanding and diagnosis of disease for diverse applications such as variant prioritization, deep phenotyping, and patient profile-matching. We have migrated our system into a scalable, cloud-based infrastructure; simplified Monarch's data ingestion and knowledge graph integration systems; enhanced data mapping and integration standards; and developed a new user interface with novel search and graph navigation features. Furthermore, we advanced Monarch's analytic tools by developing a customized plugin for OpenAI's ChatGPT to increase the reliability of its responses about phenotypic data, allowing us to interrogate the knowledge in the Monarch graph using state-of-the-art Large Language Models. The resources of the Monarch Initiative can be found at monarchinitiative.org and its corresponding code repository at github.com/monarch-initiative/monarch-app.


Assuntos
Bases de Dados Factuais , Doença , Genes , Fenótipo , Humanos , Internet , Bases de Dados Factuais/normas , Software , Genes/genética , Doença/genética
5.
Infect Immun ; 92(9): e0017524, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39007622

RESUMO

Traditionally, eosinophils have been linked to parasitic infections and pathological disease states. However, emerging literature has unveiled a more nuanced and intricate role for these cells, demonstrating their key functions in maintaining mucosal homeostasis. Eosinophils exhibit diverse phenotypes and exert multifaceted effects during infections, ranging from promoting pathogen persistence to triggering allergic reactions. Our investigations primarily focus on Bordetella spp., with particular emphasis on Bordetella bronchiseptica, a natural murine pathogen that induces diseases in mice akin to pertussis in humans. Recent findings from our published work have unveiled a striking interaction between B. bronchiseptica and eosinophils, facilitated by the btrS-mediated mechanism. This interaction serves to enhance pathogen persistence while concurrently delaying adaptive immune responses. Notably, this role of eosinophils is only noted in the absence of a functional btrS signaling pathway, indicating that wild-type B. bronchiseptica, and possibly other Bordetella spp., possess such adeptness in manipulating eosinophils that the true function of these cells remains obscured during infection. In this review, we present the mounting evidence pointing toward eosinophils as targets of bacterial exploitation, facilitating pathogen persistence and fostering chronic infections in diverse mucosal sites, including the lungs, gut, and skin. We underscore the pivotal role of the master regulator of Bordetella pathogenesis, the sigma factor BtrS, in orchestrating eosinophil-dependent immunomodulation within the context of pulmonary infection. These putative convergent strategies of targeting eosinophils offer promising avenues for the development of novel therapeutics targeting respiratory and other mucosal pathogens.


Assuntos
Infecções por Bordetella , Bordetella bronchiseptica , Eosinófilos , Imunomodulação , Eosinófilos/imunologia , Animais , Humanos , Infecções por Bordetella/imunologia , Infecções por Bordetella/microbiologia , Bordetella bronchiseptica/imunologia , Camundongos , Interações Hospedeiro-Patógeno/imunologia
6.
Am J Physiol Lung Cell Mol Physiol ; 326(6): L796-L804, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38651338

RESUMO

Secreted deoxyribonucleases (DNases), such as DNase-I and DNase-IL3, degrade extracellular DNA, and endogenous DNases have roles in resolving airway inflammation and guarding against autoimmune responses to nucleotides. Subsets of patients with asthma have high airway DNA levels, but information about DNase activity in health and in asthma is lacking. To characterize DNase activity in health and in asthma, we developed a novel kinetic assay using a Taqman probe sequence that is quickly cleaved by DNase-I to produce a large product signal. We used this kinetic assay to measure DNase activity in sputum from participants in the Severe Asthma Research Program (SARP)-3 (n = 439) and from healthy controls (n = 89). We found that DNase activity was lower than normal in asthma [78.7 relative fluorescence units (RFU)/min vs. 120.4 RFU/min, P < 0.0001]. Compared to patients with asthma with sputum DNase activity in the upper tertile activity levels, those in the lower tertile of sputum DNase activity were characterized clinically by more severe disease and pathologically by airway eosinophilia and airway mucus plugging. Carbamylation of DNase-I, a post-translational modification that can be mediated by eosinophil peroxidase, inactivated DNase-I. In summary, a Taqman probe-based DNase activity assay uncovers low DNase activity in the asthma airway that is associated with more severe disease and airway mucus plugging and may be caused, at least in part, by eosinophil-mediated carbamylation.NEW & NOTEWORTHY We developed a new DNase assay and used it to show that DNase activity is impaired in asthma airways.


Assuntos
Asma , Desoxirribonuclease I , Escarro , Humanos , Asma/metabolismo , Asma/enzimologia , Feminino , Masculino , Escarro/metabolismo , Escarro/enzimologia , Adulto , Pessoa de Meia-Idade , Desoxirribonuclease I/metabolismo , Desoxirribonucleases/metabolismo
7.
Bioinformatics ; 39(7)2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37389415

RESUMO

MOTIVATION: Knowledge graphs (KGs) are a powerful approach for integrating heterogeneous data and making inferences in biology and many other domains, but a coherent solution for constructing, exchanging, and facilitating the downstream use of KGs is lacking. RESULTS: Here we present KG-Hub, a platform that enables standardized construction, exchange, and reuse of KGs. Features include a simple, modular extract-transform-load pattern for producing graphs compliant with Biolink Model (a high-level data model for standardizing biological data), easy integration of any OBO (Open Biological and Biomedical Ontologies) ontology, cached downloads of upstream data sources, versioned and automatically updated builds with stable URLs, web-browsable storage of KG artifacts on cloud infrastructure, and easy reuse of transformed subgraphs across projects. Current KG-Hub projects span use cases including COVID-19 research, drug repurposing, microbial-environmental interactions, and rare disease research. KG-Hub is equipped with tooling to easily analyze and manipulate KGs. KG-Hub is also tightly integrated with graph machine learning (ML) tools which allow automated graph ML, including node embeddings and training of models for link prediction and node classification. AVAILABILITY AND IMPLEMENTATION: https://kghub.org.


Assuntos
Ontologias Biológicas , COVID-19 , Humanos , Reconhecimento Automatizado de Padrão , Doenças Raras , Aprendizado de Máquina
8.
Curr Microbiol ; 81(9): 274, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39017880

RESUMO

Pseudomonas aeruginosa, the most prevalent opportunistic pathogen in chronic obstructive pulmonary disease, associated with high morbidity and mortality in patients with cystic fibrosis (CF), is practically impossible to be eradicated from the airways in chronicity. Its extraordinary genomic plasticity is possibly associated with high antimicrobial resistance, virulence factors, and its phenotypic diversity. The occurrence of P. aeruginosa isolates promoting airway infection, showing mucoid, non-mucoid, and small colony variant (SCV) phenotypes, was observed simultaneously, in the present study, in sputum cultures obtained from a male CF young patient with chronic pulmonary infection for over a decade. The isolates belonged to a new ST (2744) were obtained in two moments of exacerbation of the respiratory disease, in which he was hospitalized. Genetic background and phenotypic analysis indicated that the isolates exhibited multi- and pan-antimicrobial resistant profiles, as well as non-susceptible to polymyxin and predominantly hypermutable (HPM) phenotypes. Whole genome sequencing showed variations in genome sizes, coding sequences and their determinants of resistance and virulence. The annotated genomes were compared for antimicrobial resistance, hypermutability, and SCV characteristics. We highlight the lack of reported genetic determinants of SCV emergence and HPM phenotypes, which can be explained in part due to the very short time between collections of isolates. To the best of our knowledge, this is the first report of genome sequencing of P. aeruginosa SCV from a CF patient in Brazil.


Assuntos
Antibacterianos , Fibrose Cística , Fenótipo , Infecções por Pseudomonas , Pseudomonas aeruginosa , Humanos , Fibrose Cística/microbiologia , Fibrose Cística/complicações , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Pseudomonas aeruginosa/patogenicidade , Masculino , Infecções por Pseudomonas/microbiologia , Antibacterianos/farmacologia , Genoma Bacteriano , Testes de Sensibilidade Microbiana , Escarro/microbiologia , Fatores de Virulência/genética , Sequenciamento Completo do Genoma
9.
Proc Natl Acad Sci U S A ; 118(30)2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34301870

RESUMO

Genome-wide association studies have identified the chromosome 10q26 (Chr10) locus, which contains the age-related maculopathy susceptibility 2 (ARMS2) and high temperature requirement A serine peptidase 1 (HTRA1) genes, as the strongest genetic risk factor for age-related macular degeneration (AMD) [L.G. Fritsche et al., Annu. Rev. Genomics Hum. Genet. 15, 151-171, (2014)]. To date, it has been difficult to assign causality to any specific single nucleotide polymorphism (SNP), haplotype, or gene within this region because of high linkage disequilibrium among the disease-associated variants [J. Jakobsdottir et al. Am. J. Hum. Genet. 77, 389-407 (2005); A. Rivera et al. Hum. Mol. Genet. 14, 3227-3236 (2005)]. Here, we show that HTRA1 messenger RNA (mRNA) is reduced in retinal pigment epithelium (RPE) but not in neural retina or choroid tissues derived from human donors with homozygous risk at the 10q26 locus. This tissue-specific decrease is mediated by the presence of a noncoding, cis-regulatory element overlapping the ARMS2 intron, which contains a potential Lhx2 transcription factor binding site that is disrupted by risk variant rs36212733. HtrA1 protein increases with age in the RPE-Bruch's membrane (BM) interface in Chr10 nonrisk donors but fails to increase in donors with homozygous risk at the 10q26 locus. We propose that HtrA1, an extracellular chaperone and serine protease, functions to maintain the optimal integrity of the RPE-BM interface during the aging process and that reduced expression of HTRA1 mRNA and protein in Chr10 risk donors impairs this protective function, leading to increased risk of AMD pathogenesis. HtrA1 augmentation, not inhibition, in high-risk patients should be considered as a potential therapy for AMD.


Assuntos
Predisposição Genética para Doença , Serina Peptidase 1 de Requerimento de Alta Temperatura A/metabolismo , Degeneração Macular/genética , Epitélio Pigmentado da Retina/metabolismo , Corioide/metabolismo , Variação Genética , Serina Peptidase 1 de Requerimento de Alta Temperatura A/genética , Humanos , Desequilíbrio de Ligação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Retina/metabolismo
10.
Crit Rev Biochem Mol Biol ; 56(1): 88-108, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33349060

RESUMO

HEPN (Higher Eukaryotes and Prokaryotes Nucleotide-binding) RNases are an emerging class of functionally diverse RNA processing and degradation enzymes. Members are defined by a small α-helical bundle encompassing a short consensus RNase motif. HEPN dimerization is a universal requirement for RNase activation as the conserved RNase motifs are precisely positioned at the dimer interface to form a composite catalytic center. While the core HEPN fold is conserved, the organization surrounding the HEPN dimer can support large structural deviations that contribute to their specialized functions. HEPN RNases are conserved throughout evolution and include bacterial HEPN RNases such as CRISPR-Cas and toxin-antitoxin associated nucleases, as well as eukaryotic HEPN RNases that adopt large multi-component machines. Here we summarize the canonical elements of the growing HEPN RNase family and identify molecular features that influence RNase function and regulation. We explore similarities and differences between members of the HEPN RNase family and describe the current mechanisms for HEPN RNase activation and inhibition.


Assuntos
Endorribonucleases/metabolismo , Proteólise , Processamento Pós-Transcricional do RNA , Proteínas de Ligação a RNA/metabolismo , Sequência de Aminoácidos , Animais , Sistemas CRISPR-Cas , Domínio Catalítico , Endorribonucleases/química , Endorribonucleases/genética , Humanos , Conformação Proteica em alfa-Hélice , Multimerização Proteica , Estabilidade de RNA , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Sistemas Toxina-Antitoxina
11.
Mamm Genome ; 34(3): 364-378, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37076585

RESUMO

Existing phenotype ontologies were originally developed to represent phenotypes that manifest as a character state in relation to a wild-type or other reference. However, these do not include the phenotypic trait or attribute categories required for the annotation of genome-wide association studies (GWAS), Quantitative Trait Loci (QTL) mappings or any population-focussed measurable trait data. The integration of trait and biological attribute information with an ever increasing body of chemical, environmental and biological data greatly facilitates computational analyses and it is also highly relevant to biomedical and clinical applications. The Ontology of Biological Attributes (OBA) is a formalised, species-independent collection of interoperable phenotypic trait categories that is intended to fulfil a data integration role. OBA is a standardised representational framework for observable attributes that are characteristics of biological entities, organisms, or parts of organisms. OBA has a modular design which provides several benefits for users and data integrators, including an automated and meaningful classification of trait terms computed on the basis of logical inferences drawn from domain-specific ontologies for cells, anatomical and other relevant entities. The logical axioms in OBA also provide a previously missing bridge that can computationally link Mendelian phenotypes with GWAS and quantitative traits. The term components in OBA provide semantic links and enable knowledge and data integration across specialised research community boundaries, thereby breaking silos.


Assuntos
Ontologias Biológicas , Disciplinas das Ciências Biológicas , Estudo de Associação Genômica Ampla , Fenótipo
12.
Calcif Tissue Int ; 113(5): 496-510, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37690031

RESUMO

Components of the renin-angiotensin-aldosterone system (RAAS) are present on bone cells. One measure of RAAS activity, the aldosterone-renin-ratio (ARR), is used to screen for primary aldosteronism. Associations between ARR and bone mineral density are conflicting. This study investigated associations between ARR and peripheral quantitative computed tomography (pQCT) and impact microindentation (IMI). Male participants (n = 431) were from the Geelong Osteoporosis Study. "Likely" primary aldosteronism was defined as ARR ≥ 70 pmol/mIU. Another group, "possible" primary aldosteronism, was defined as either ARR ≥ 70 pmol/mIU or taking a medication that affects the RAAS, but not a beta blocker, and renin < 15 mU/L. Using pQCT, images at 4% and 66% of radial (n = 365) and tibial (n = 356) length were obtained. Using IMI measurements, bone material strength index (BMSi; n = 332) was determined. Associations between ARR or likely/possible primary aldosteronism and IMI or pQCT-derived bone parameters were tested using median regression. ARR and aldosterone values were not associated with any of the pQCT-derived bone variables in either unadjusted or adjusted analyses. Men with likely primary aldosteronism (n = 16), had lower adjusted total bone area (radial 66% site, - 12.5%). No associations were observed for men with possible primary aldosteronism (unadjusted or adjusted). No associations with BMSi were observed (p > 0.05). There were no associations between ARR or aldosterone and pQCT-derived bone parameters. Men with likely primary aldosteronism had lower bone area, suggesting clinically high levels of ARR may have a negative impact on bone health.


Assuntos
Hiperaldosteronismo , Hipertensão , Humanos , Masculino , Aldosterona/uso terapêutico , Renina/uso terapêutico , Hiperaldosteronismo/complicações , Sistema Renina-Angiotensina , Tomografia Computadorizada por Raios X , Hipertensão/complicações , Hipertensão/tratamento farmacológico
13.
J Bone Miner Metab ; 41(1): 131-142, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36550385

RESUMO

INTRODUCTION: Individuals with type 2 diabetes mellitus (T2DM) are at higher risk of fracture, but paradoxically do not have reduced bone mineral density. We investigated associations between peripheral quantitative computed tomography (pQCT) and glycaemia status. MATERIALS AND METHODS: Participants were men (n = 354, age 33-92 year) from the Geelong Osteoporosis Study. Diabetes was defined by fasting plasma glucose (FPG) ≥ 7.0 mmol/L, self-report of diabetes and/or antihyperglycaemic medication use and impaired fasting glucose (IFG) as FPG 5.6-6.9 mmol/L. Bone measures were derived using pQCT (XCT2000) at 4% and 66% radial and tibial sites. Linear regression was used, adjusting for age, body mass index and socio-economic status. RESULTS: At the 4% site, men with T2DM had lower adjusted bone total area, trabecular area and cortical area at the radius (all - 6.2%) and tibia (all - 6.4%) compared to normoglycaemia. Cortical density was higher for T2DM at the radius (+ 5.8%) and tibia (+ 8.0%), as well as adjusted total bone density at the tibial site (+ 6.1%). At the 66% site, adjusted total bone area and polar stress strain index were lower for T2DM at the radius (- 4.3% and - 8.0%). Total density was also higher for T2DM (+ 1.2%). Only cortical density at the 4% tibial site was different between IFG and normoglycaemia in adjusted analyses (+ 4.5%). CONCLUSION: Men with T2DM had lower total bone area, trabecular area, cortical area and polar stress strain index than the other two groups; however, total density and cortical density were higher. Only one difference was observed between IFG and normoglycaemia; increased tibial cortical density.


Assuntos
Diabetes Mellitus Tipo 2 , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Osso e Ossos , Densidade Óssea , Rádio (Anatomia)/diagnóstico por imagem , Tíbia/diagnóstico por imagem , Jejum , Tomografia , Glucose
14.
Microb Ecol ; 85(1): 137-145, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35066616

RESUMO

The use of metal-based and, particularly, Al2O3 nanoparticles (Al2O3-NP) for diverse purposes is exponentially growing. However, the growth of such promissory market is not accompanied by a parallel extensive investigation related to the impact of this pollution on groundwater and biological systems. Pseudomonas species, ubiquitous, environmentally critical microbes, frequently respond to stress conditions with diverse strategies that generally include extracellular polymeric substances (EPS) formation. The aim of this study is to report that changes in the aqueous environment, particularly, the addition of Al2O3-NP without and with humic acids, induce different adaptive strategies of Pseudomonas aeruginosa early biofilms. To this purpose, early biofilms were incubated in diluted culture media without (control) and with Al2O3-NP, and with humic acids (HA-control, HA-Al2O3-NP) for 24 h. 3D colonies with EPS strings and isolated bacteria in their surroundings were detected in the control biofilms. Unlikely, an unusual adaptive behaviour was developed in the presence of Al2O3-NP. Bacteria opt to disassemble the 3D arrangements and to implement a 2D network promoting morphological and size changes of bacterial cells (small coccoid shapes). Remarkably, this strategy allows their temporarily non-EPS-depending survival without decreasing the number of cells. This behaviour was not observed with ZnO-NP, HA-Al2O3-NP, or HA-ZnO-NP. Physicochemical analysis revealed that HA were adsorbed on Al2O3-NP and promoted the Al(III) ions complexation. This supports the hypothesis that the reduction of toxicity of Al ions and the 3D colony formation in the presence of HA-Al2O3-NP is promoted by the complexation of the metal ions with HA components.


Assuntos
Microbiota , Nanopartículas , Óxido de Zinco , Substâncias Húmicas/análise , Óxido de Zinco/química , Íons
15.
J Hered ; 114(5): 459-469, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37162284

RESUMO

The Bermuda petrel Pterodroma cahow is an island endemic seabird that belongs to the Procellariiformes, one of the most endangered orders of birds. Historical records suggest a significant population size decline following human settlement in Bermuda, bringing the species to near extinction. Since the 1950s, the population has been recovering aided by the implementation of an ongoing conservation plan. However, it still faces several threats, and negative genetic effects resulting from that drastic decline are to be expected, including inbreeding and genetic drift. We studied genetic diversity and levels of inbreeding, and their effects on individual fitness and mating choice. We also tested for a genetic signature of the recent demographic bottleneck. For this, we analyzed variation in thousands of nuclear single-nucleotide polymorphisms derived from double digest restriction site-associated DNA sequencing and 1 mitochondrial gene (cytochrome oxidase I). The results revealed that the Bermuda petrel suffered a recent genetic bottleneck and shows low mitochondrial diversity compared with other petrel species. Conversely, nuclear diversity was similar to that of other endangered petrels. Inbreeding levels were not high overall, although some individuals were highly inbred. However, we found no evidence that individual inbreeding or relatedness between mates affected hatching success, or that mate choice is influenced by kinship in this very small population.


Assuntos
Variação Genética , Depressão por Endogamia , Humanos , Animais , Bermudas , Aves/genética , Endogamia , Espécies em Perigo de Extinção
16.
Mol Cell ; 59(6): 970-83, 2015 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-26344097

RESUMO

BRCC36 is a Zn(2+)-dependent deubiquitinating enzyme (DUB) that hydrolyzes lysine-63-linked ubiquitin chains as part of distinct macromolecular complexes that participate in either interferon signaling or DNA-damage recognition. The MPN(+) domain protein BRCC36 associates with pseudo DUB MPN(-) proteins KIAA0157 or Abraxas, which are essential for BRCC36 enzymatic activity. To understand the basis for BRCC36 regulation, we have solved the structure of an active BRCC36-KIAA0157 heterodimer and an inactive BRCC36 homodimer. Structural and functional characterizations show how BRCC36 is switched to an active conformation by contacts with KIAA0157. Higher-order association of BRCC36 and KIAA0157 into a dimer of heterodimers (super dimers) was required for DUB activity and interaction with targeting proteins SHMT2 and RAP80. These data provide an explanation of how an inactive pseudo DUB allosterically activates a cognate DUB partner and implicates super dimerization as a new regulatory mechanism underlying BRCC36 DUB activity, subcellular localization, and biological function.


Assuntos
Formigas/enzimologia , Proteínas de Insetos/química , Proteínas Associadas à Matriz Nuclear/química , Proteases Específicas de Ubiquitina/química , Animais , Domínio Catalítico , Cristalografia por Raios X , Enzimas Desubiquitinantes , Células HEK293 , Células HeLa , Humanos , Proteínas de Insetos/fisiologia , Cinética , Proteínas de Membrana/química , Modelos Moleculares , Proteínas Associadas à Matriz Nuclear/fisiologia , Ligação Proteica , Multimerização Proteica , Estrutura Quaternária de Proteína , Estrutura Secundária de Proteína , Proteases Específicas de Ubiquitina/fisiologia
17.
Public Health Nutr ; 26(7): 1478-1487, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36912105

RESUMO

OBJECTIVE: To determine predictors of the association between being a Veteran and adult food security, as well as to examine the relation of potential covariates to this relationship. DESIGN: Data collected during 2011-2012, 2013-2014 and 2015-2016 National Health and Nutrition Examination Survey (NHANES) were pooled for analyses. Veterans (self-reported) were matched to non-Veterans on age, race/ethnicity, sex and education. Adjusted logistic regression was used to determine the odds of Veterans having high food security v. the combination of marginal, low and very low food security compared with non-Veterans. SETTING: 2011-2012, 2013-2014 and 2015-2016 NHANES. PARTICIPANTS: 1227 Veterans; 2432 non-Veterans. RESULTS: Veteran status had no effect on the proportion of food insecurities between Veterans and non-Veterans reporting high (Veterans v. non-Veteran: 79 % v. 80 %), marginal (9 % v. 8 %), low (5 % v. 6 %) and very low (8 % v. 6 %) food security (P = 0·11). However, after controlling for covariates, Veterans tended to be less likely to have high food security (OR: 0·82 (95 % CI 0·66, 1·02), P = 0·07). Further, non-Hispanic White Veterans (OR: 0·72 (95 % CI 0·55, 0·95), P = 0·02) and Veterans completing some college (OR: 0·71 (95 % CI 0·50, 0·99), P < 0·05) were significantly less likely to experience high food security compared with non-Veterans. CONCLUSION: This study supports previous research findings that after controlling for covariates, Veterans tend to be less likely to have high food security. It also highlights ethnicity and level of education as important socio-economic determinates of food security status in Veterans.


Assuntos
Abastecimento de Alimentos , Pobreza , Adulto , Humanos , Inquéritos Nutricionais , Prevalência , Insegurança Alimentar
18.
Nucleic Acids Res ; 49(17): 10136-10149, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-34403466

RESUMO

Nsp15 is a uridine specific endoribonuclease that coronaviruses employ to cleave viral RNA and evade host immune defense systems. Previous structures of Nsp15 from across Coronaviridae revealed that Nsp15 assembles into a homo-hexamer and has a conserved active site similar to RNase A. Beyond a preference for cleaving RNA 3' of uridines, it is unknown if Nsp15 has any additional substrate preferences. Here, we used cryo-EM to capture structures of Nsp15 bound to RNA in pre- and post-cleavage states. The structures along with molecular dynamics and biochemical assays revealed critical residues involved in substrate specificity, nuclease activity, and oligomerization. Moreover, we determined how the sequence of the RNA substrate dictates cleavage and found that outside of polyU tracts, Nsp15 has a strong preference for purines 3' of the cleaved uridine. This work advances our understanding of how Nsp15 recognizes and processes viral RNA, and will aid in the development of new anti-viral therapeutics.


Assuntos
Endorribonucleases/metabolismo , RNA Viral/metabolismo , SARS-CoV-2/genética , Uridina/química , Proteínas não Estruturais Virais/metabolismo , COVID-19/virologia , Domínio Catalítico/genética , Microscopia Crioeletrônica , Cristalografia por Raios X , Humanos , Simulação de Dinâmica Molecular , Multimerização Proteica/fisiologia , RNA Viral/genética , Especificidade por Substrato
19.
Nucleic Acids Res ; 49(D1): D1207-D1217, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33264411

RESUMO

The Human Phenotype Ontology (HPO, https://hpo.jax.org) was launched in 2008 to provide a comprehensive logical standard to describe and computationally analyze phenotypic abnormalities found in human disease. The HPO is now a worldwide standard for phenotype exchange. The HPO has grown steadily since its inception due to considerable contributions from clinical experts and researchers from a diverse range of disciplines. Here, we present recent major extensions of the HPO for neurology, nephrology, immunology, pulmonology, newborn screening, and other areas. For example, the seizure subontology now reflects the International League Against Epilepsy (ILAE) guidelines and these enhancements have already shown clinical validity. We present new efforts to harmonize computational definitions of phenotypic abnormalities across the HPO and multiple phenotype ontologies used for animal models of disease. These efforts will benefit software such as Exomiser by improving the accuracy and scope of cross-species phenotype matching. The computational modeling strategy used by the HPO to define disease entities and phenotypic features and distinguish between them is explained in detail.We also report on recent efforts to translate the HPO into indigenous languages. Finally, we summarize recent advances in the use of HPO in electronic health record systems.


Assuntos
Ontologias Biológicas , Biologia Computacional/métodos , Bases de Dados Factuais , Doença/genética , Genoma , Fenótipo , Software , Animais , Modelos Animais de Doenças , Genótipo , Humanos , Recém-Nascido , Cooperação Internacional , Internet , Triagem Neonatal/métodos , Farmacogenética/métodos , Terminologia como Assunto
20.
An Acad Bras Cienc ; 95(suppl 1): e20200495, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37646705

RESUMO

The objective was to determine the zootechnical performance of broiler chickens fed different diets containing cassava meal. A total of 450 male broiler chickens of the Cobb lineage was used. The experimental design was completely randomized with five treatments (0, 25, 50, 75, and 100% inclusion of cassava meal) and five replications, composed of 18 birds per experimental unit. Morphometric characteristics of broiler chickens were evaluated: live weight, and weights of full and empty carcasses, livers, hearts, full and empty gizzards, abdominal fat, wings, thighs, drumsticks, breasts, and dorse. Data were tested using an analysis of variance, regression model, and cluster and discriminant analyses. There was a difference in the weight of the heart, full gizzard, wing, thigh, drumstick, and breast in relation to the different diets. The inclusion of 8.2%, 57.57%, and 25.38% cassava meal maximized thighs at 323.96 g, drumsticks at 385.04 g, and breasts at 921.12 g, respectively. The formation of two groups of birds was verified, and the classification rate was 92%. Inclusion of up to 50% cassava meal in the broiler diet did not alter its zootechnical performance, implying a lower cost of production.


Assuntos
Galinhas , Manihot , Animais , Masculino , Verduras , Coração , Fígado
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