Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 317
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Cell ; 187(9): 2158-2174.e19, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38604175

RESUMO

Centriole biogenesis, as in most organelle assemblies, involves the sequential recruitment of sub-structural elements that will support its function. To uncover this process, we correlated the spatial location of 24 centriolar proteins with structural features using expansion microscopy. A time-series reconstruction of protein distributions throughout human procentriole assembly unveiled the molecular architecture of the centriole biogenesis steps. We found that the process initiates with the formation of a naked cartwheel devoid of microtubules. Next, the bloom phase progresses with microtubule blade assembly, concomitantly with radial separation and rapid cartwheel growth. In the subsequent elongation phase, the tubulin backbone grows linearly with the recruitment of the A-C linker, followed by proteins of the inner scaffold (IS). By following six structural modules, we modeled 4D assembly of the human centriole. Collectively, this work provides a framework to investigate the spatial and temporal assembly of large macromolecules.


Assuntos
Centríolos , Microtúbulos , Centríolos/metabolismo , Humanos , Microtúbulos/metabolismo , Tubulina (Proteína)/metabolismo , Proteínas de Ciclo Celular/metabolismo
2.
Int J Mol Sci ; 25(6)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38542300

RESUMO

Worldwide, the number of elderly individuals receiving chronic hemodialysis is rising. The aim of our study was to evaluate several clinical and analytical biomarkers in chronically dialyzed patients and analyze how they change with age. A cross-sectional study was performed by evaluating 289 end-stage renal disease patients undergoing dialysis. We evaluated the hemogram, adipokines, the lipid profile, and several markers related to inflammation, endothelial function/fibrinolysis, nutrition, iron metabolism, and cardiac and renal fibrosis. Clinical data and dialysis efficacy parameters were obtained from all patients. The relationships between studied biomarkers and age were assessed by a statistical comparison between younger (adults with age < 65 years) and older (age ≥ 65 years) patients and by performing regression analysis. Participants presented a mean age of 68.7 years (±13.6), with 66.8% (n = 193) being classified as older. Compared to younger patients, older patients presented the following: (a) significantly lower values of diastolic blood pressure (DBP) and ultrafiltration volume; (b) lower levels of phosphorus, uric acid, creatinine, and albumin; and (c) higher circulating concentrations of tissue-type plasminogen activator (tPA), D-dimer, interleukin-6, leptin, N-terminal pro B-type natriuretic peptide, and tissue inhibitor of metalloproteinase-1. In the multiple linear regression analysis, DBP values, tPA, phosphorus, and D-dimer levels were independently associated with the age of patients (standardized betas: -0.407, 0.272, -0.230, and 0.197, respectively; p < 0.001 for all), demonstrating relevant changes in biomarkers with increasing age at cardiovascular and nutritional levels. These findings seem to result from crosstalk mechanisms between aging and chronic kidney disease.


Assuntos
Falência Renal Crônica , Inibidor Tecidual de Metaloproteinase-1 , Adulto , Humanos , Idoso , Estudos Transversais , Diálise Renal , Falência Renal Crônica/complicações , Biomarcadores , Fósforo
3.
Mol Biol Evol ; 39(4)2022 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-35383854

RESUMO

In a recent article, Immel et al. (Immel A, Key FM, Szolek A, Barquera R, Robinson MK, Harrison GF, Palmer WH, Spyrou MA, Susat J, Krause-Kyora B, et al. 2021. Analysis of genomic DNA from medieval plague victims suggests long-term effect of Yersinia pestis on human immunity genes. Mol Biol Evol. 38:4059-4076) extracted DNA from 36 individuals dead from plague in Ellwangen, Southern Germany, during the 16th century. By comparing their human leukocyte antigen (HLA) genotypes with those of 50 present-day Ellwangen inhabitants, the authors reported a significant decrease of HLA-B*51:01 and HLA-C*06:02 and a significant increase of HLA-DRB1*13:01/13:02 frequencies from ancient to modern populations. After comparing these frequencies with a larger sample of 8,862 modern Germans and performing simulations of natural selection, they concluded that these changes had been driven by natural selection. In an attempt to provide more evidence on such stimulating results, we explored the HLA frequency patterns over all of Europe, we predicted binding affinities of HLA-B/C/DRB1 alleles to 106,515 Yersinia pestis-derived peptides, and we performed forward simulations of HLA genetic profiles under neutrality. Our analyses do not sustain the conclusions of HLA protection or susceptibility to plague based on ancient DNA.


Assuntos
Predisposição Genética para Doença , Antígenos HLA , Peste , DNA , DNA Antigo , Europa (Continente) , Antígenos HLA/genética , Antígenos de Histocompatibilidade Classe II , Humanos , Peste/genética , Yersinia pestis
4.
Mol Phylogenet Evol ; 183: 107752, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36893930

RESUMO

Cystocloniacae is a highly diverse family of Rhodophyta, including species of ecological and economic importance, whose phylogeny remains largely unresolved. Species delimitation is unclear, particularly in the most speciose genus, Hypnea, and cryptic diversity has been revealed by recent molecular assessments, especially in the tropics. Here, we carried out the first phylogenomic investigation of Cystocloniaceae, focused on the genus Hypnea, inferred from chloroplast and mitochondrial genomes including taxa sampled from new and historical collections. In this work, molecular synapomorphies (gene losses, InDels and gene inversions) were identified to better characterize clades in our congruent organellar phylogenies. We also present taxon-rich phylogenies based on plastid and mitochondrial markers. Molecular and morphological comparisons of historic collections with contemporary specimens revealed the need for taxonomic updates in Hypnea, the synonymization of H. marchantiae to a later heterotypic synonym of H. cervicornis and the description of three new species: H. davisiana sp. nov., H. djamilae sp. nov. and H. evaristoae sp. nov.


Assuntos
Rodófitas , Filogenia , Rodófitas/genética , Organelas , Mitocôndrias , Cloroplastos
5.
Nutr Metab Cardiovasc Dis ; 33(2): 369-375, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36642605

RESUMO

BACKGROUND & AIMS: Rheumatoid Arthritis (RA) is a chronic inflammatory autoimmune disease affecting the joints. It has been suggested that obesity increases the likelihood of RA development lowers the chance to achieve low disease activity and disease remission. The purpose of the study was to analyze the nutritional status of a cohort of persons with RA and compare to cohorts of persons with other arthritis and without. METHODS AND RESULTS: We used the NHANES database from 2015 to 2018, assessing anthropometric data, body composition, micronutrients, bone metabolism, protein content and laboratory data from those participants; and to compared to others without arthritis or with other forms of arthritis. We included 19,225 participants, with an estimation of population size of 637,323,765 and female preponderance of 52% and an average age of 38 ± 0,4 yrs. RA had an incidence of 4.5% and other arthritis (OA) of 15%. There was a higher prevalence of overweight and obesity, central obesity and percentage of body fat in RA and OA. Obesity related conditions such as dyslipidemia, diabetes, and hypertension were more prevalent in those participants. Fasting glucose levels, oral glucose tolerance test at 2 h, insulin levels and HbA1c were all significantly higher in persons with RA and OA. CONCLUSION: The higher prevalence of metabolic syndrome together with the inflammatory state of RA, constitute important cardiovascular risk factors, which should be addressed aggressively preferably by primary prevention.


Assuntos
Artrite Reumatoide , Síndrome Metabólica , Humanos , Feminino , Estado Nutricional , Inquéritos Nutricionais , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/epidemiologia , Artrite Reumatoide/metabolismo , Obesidade/diagnóstico , Obesidade/epidemiologia , Síndrome Metabólica/diagnóstico , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/metabolismo
6.
J Environ Manage ; 334: 117430, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36801681

RESUMO

Imazamox (IMZX) is a persistent herbicide having probable risks for non-target organisms in the environment and water contamination. Alternatives to conventional flooding rice production, including biochar amendment, may induce changes in soil properties which can greatly modify the environmental fate of IMZX. This two-year study is the first to evaluate how tillage and irrigation practices, with or without fresh or aged biochar (Bc), that are alternatives to conventional rice production impact IMZX's environmental fate. The treatments were: conventional tillage and flooding irrigation (CTFI), conventional tillage and sprinkler irrigation (CTSI), no-tillage and sprinkler irrigation (NTSI), and the corresponding Bc-amendment treatments (CTFI-Bc, CTSI-Bc, and NTSI-Bc). Fresh and aged Bc amendment decreased IMZX's sorption onto the soil in tillage treatments, with Kf values decreasing 3.7 and 4.2-fold (fresh case) and 1.5 and 2.6-fold (aged case) for CTSI-Bc and CTFI-Bc, respectively. The transition to sprinkler irrigation reduced IMZX persistence. Overall, Bc amendment also reduced chemical persistence with half-life values decreasing 1.6 and 1.5-fold for CTFI and CTSI (fresh year) and 1.1, 1.1, and 1.3-fold for CTFI, CTSI, and NTSI (aged year), respectively. Sprinkler irrigation reduced IMZX leaching by up to a factor of 2.2. The use of Bc as amendment led to a significant decrease in IMZX leaching only under tillage conditions, but notable in particular for the CTFI case where leaching losses were reduced in the fresh year from 80% to 34% and, in the aged year, from 74% to 50%. Hence the change in irrigation from flooding to sprinkler either alone or in combination with the use of Bc (fresh or aged) amendment could be considered an effective way to sharply mitigate IMZX contamination of water in environments where rice is grown, particularly in those managed with tillage.


Assuntos
Oryza , Poluentes do Solo , Solo/química , Carvão Vegetal/química , Água
7.
Mol Biol Evol ; 38(4): 1580-1594, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33320202

RESUMO

Human leukocyte antigen (HLA) genes are among the most polymorphic of our genome, as a likely consequence of balancing selection related to their central role in adaptive immunity. HLA-A and HLA-B genes were recently suggested to evolve through a model of joint divergent asymmetric selection conferring all human populations, including those with severe loss of diversity, an equivalent immune potential. However, the mechanisms by which these two genes might undergo joint evolution while displaying very distinct allelic profiles in populations are still unknown. To address this issue, we carried out extensive data analyses (among which factorial correspondence analysis and linear modeling) on 2,909 common and rare HLA-A, HLA-B, and HLA-C alleles and 200,000 simulated pathogenic peptides by taking into account sequence variation, predicted peptide-binding affinity and HLA allele frequencies in 123 populations worldwide. Our results show that HLA-A and HLA-B (but not HLA-C) molecules maintain considerable functional divergence in almost all populations, which likely plays an instrumental role in their immune defense. We also provide robust evidence of functional complementarity between HLA-A and HLA-B molecules, which display asymmetric relationships in terms of amino acid diversity at both inter- and intraprotein levels and in terms of promiscuous or fastidious peptide-binding specificities. Like two wings of a flying bird, the functional complementarity of HLA-A and HLA-B is a perfect example, in our genome, of duplicated genes sharing their capacity of assuming common vital functions while being submitted to complex and sometimes distinct environmental pressures.


Assuntos
Evolução Molecular , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Seleção Genética , Alelos , Sequência de Aminoácidos , Antígenos HLA-A/química , Antígenos HLA-B/química , Humanos
8.
Mol Phylogenet Evol ; 165: 107294, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34419587

RESUMO

The Gracilariales is a highly diverse, widely distributed order of red algae (Rhodophyta) that forms a well-supported clade. Aside from their ecological importance, species of Gracilariales provide important sources of agarans and possess bioactive compounds with medicinal and pharmaceutical use. Recent phylogenetic analyses from a small number of genes have greatly advanced our knowledge of evolutionary relationships in this clade, yet several key nodes were not especially well resolved. We assembled a phylogenomic data set containing 79 nuclear genes, 195 plastid genes, and 24 mitochondrial genes from species representing all three major Gracilariales lineages, including: Melanthalia, Gracilariopsis, and Gracilaria sensu lato. This data set leads to a fully-resolved phylogeny of Gracilariales, which is highly-consistent across genomic compartments. In agreement with previous findings, Melanthalia obtusata was sister to a clade including Gracilaria s.l. and Gracilariopsis, which were each resolved as well-supported clades. Our results also clarified the long-standing uncertainty about relationships in Gracilaria s.l., not resolved in single and multi-genes approaches. We further characterized the divergence time, organellar genome architecture, and morphological trait evolution in Gracilarales to better facilitate its taxonomic treatment. Gracilariopsis and Gracilaria s.l. are comparable taxonomic ranks, based on the overlapping time range of their divergence. The genomic structure of plastid and mitochondria is highly conserved within each clade but differs slightly among these clades in gene contents. For example, the plastid gene petP is lost in Gracilaria s.l. and the mitochondrial gene trnH is in different positions in the genome of Gracilariopsis and Gracilaria s.l. Our analyses of ancestral character evolution provide evidence that the main characters used to delimitate genera in Gracilariales, such as spermatangia type and features of the cystocarp's anatomy, overlap in subclades of Gracilaria s.l. We discuss the taxonomy of Gracilariales in light of these results and propose an objective and practical classification, which is in agreement with the criteria of monophyly, exclusive characters, predictability and nomenclatural stability.


Assuntos
Gracilaria , Rodófitas , Genes Mitocondriais , Gracilaria/genética , Filogenia , Plastídeos/genética , Rodófitas/genética
9.
Rev Cardiovasc Med ; 22(3): 903-910, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34565089

RESUMO

Exercise-based cardiac rehabilitation (EBCR) is paramount after an acute myocardial infarction (AMI). Older individuals have been reported as having a worse prognosis after an AMI, and some series have reported differences in the functional response to EBCR. The peak circulatory power (CP), a non-invasive parameter, has been described as a surrogate for the cardiac power, showing promising results as a comprehensive measure of the cardiovascular response. Whilst this, data concerning the impact of EBCR on CP, particularly among elderly individuals, remains elusive. To address this issue, an observational, retrospective study including all patients admitted due to an AMI who completed a phase II EBCR programme between 11/2012 and 4/2017, was conducted, with CP being analysed by a symptom-limited cardiopulmonary exercise test. A total of 379 patients, 30% aged ≥65 years-old, were included. CP significantly improved after the EBCR programme (in all patients, as well as in both subgroups). Older patients presented lower CP than their younger counterparts at the beginning and the end of the programme, while presenting smaller improvements (122 ± 540 vs 293 ± 638 mmHg mL/kg/min, p = 0.013). This was maintained after adjusting for several potential confounding factors. A contemporary ECBR programme was associated with significant improvements in CP among AMI patients. Though those aged ≥65 years-old presented smaller improvements in CP than younger individuals, these still presented significant increases in this parameter. These results highlight the importance of EBCR in this challenging higher risk group of patients.


Assuntos
Reabilitação Cardíaca , Infarto do Miocárdio , Idoso , Terapia por Exercício , Humanos , Infarto do Miocárdio/diagnóstico , Estudos Retrospectivos , Sobreviventes
10.
J Phycol ; 57(6): 1749-1767, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34448497

RESUMO

The Peyssonneliaceae represents the only family in the order Peyssonneliales, a clade of red encrusting algae distributed worldwide, including 136 species in eleven currently accepted genera. Delineation of genera in the Peyssonneliaceae has mostly been based on vegetative characteristics. Previous molecular phylogenies have shown that some traditionally circumscribed genera are not monophyletic and relationships among them are uncertain. We contribute to the knowledge of the evolutionary history of this clade, presenting a robust rbcL phylogeny that provides new insights on the origin and diversification of the Peyssonneliales. Based on a broad dataset and morphological analyses, we propose a revised taxonomic scheme for the Peyssonneliales resolved as monophyletic with well-supported main lineages. Our results show that Peyssonnelia is polyphyletic, and, therefore, we propose three new genera, Agissea, Olokunia, and Rhodowynnea to accommodate species currently assigned to Peyssonnelia, but distantly related to the clade with the type species of the genus. Additionally, barcoding techniques and analyzed criteria for specific delimitation supported the establishment of one new genus, Brasilophycus, and seven new species, from northeastern Brazil: Agissea amadoi, A. densissima, A. taberniforma, A. villatlantica, A. yemonjasagbae, Brasilophycus similis, and B. roseomarginatus. Our integrative taxonomic approach reveals underestimated diversity of Brazilian Peyssonneliales. Investment in broader sampling along the Brazilian coast and other tropical areas may reveal that its marine biodiversity can be expanded, enlightening our knowledge about this ecologically important group of red algae.


Assuntos
Rodófitas , Biodiversidade , Evolução Biológica , Brasil , Filogenia , Rodófitas/genética
11.
South Med J ; 114(11): 697-702, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34729613

RESUMO

OBJECTIVE: The aim of our systematic review was to update the current evidence on the association between slow walking speed (WS) and mortality, expanding the current knowledge available in the literature. METHODS: A systematic review of the published data on the association of WS and mortality was carried out by searching on PubMed and ISI Web of Knowledge databases. RESULTS: From a title and abstract analysis, 61 articles were included that met the prespecified criteria. After a full-text analysis, 6 articles were excluded and the remaining articles accounted for 120,838 patients and > 25,148 deaths were registered. The duration of follow-ups ranged between 2 and 21 years. In general, studies have shown a consistent association between WS and mortality from all causes. CONCLUSIONS: WS showed continuous and consistent evidence to be a good predictor of mortality. As such, our study supports the use of this tool in clinical practice as a way to improve health care.


Assuntos
Mortalidade/tendências , Velocidade de Caminhada/fisiologia , Humanos
12.
J Fish Biol ; 99(4): 1292-1298, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34180056

RESUMO

In this study, a new species of Pseudogilbia Møller, Schwarzhans & Nielsen 2004 is described based on two male specimens (40-44 mm LS ) from shallow reefs of Bahia, Brazil. Pseudogilbia australis sp. nov. is distinguished from its only congener, Pseudogilbia sanblasensis Møller, Schwarzhans & Nielsen 2004 from Caribbean Panama, by having: two lower preopercular pores (vs. one); dorsal-fin rays 65-67 (vs. 69); anal-fin rays 51-53 (vs. 56); pectoral-fin rays 18 (vs. 20); caudal vertebrae 27-28 (vs. 30); pectoral-fin length 15.0%-15.9% LS (vs. 14.3); pelvic-fin length 13.5% LS (vs. 16.4) and a different morphology of the male copulatory organ. Pseudogilbia australis sp. nov. is the only dinematichthyid so far recorded in the South Atlantic. An updated diagnosis for the genus is also provided.


Assuntos
Perciformes , Animais , Brasil , Região do Caribe , Peixes , Masculino , Panamá
13.
Monaldi Arch Chest Dis ; 92(1)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34461703

RESUMO

Exercise is a pivotal physiological activity, associated with benefits. Whilst the importance of physical activity is consensual along different steps of the cardiovascular (CV) continuum, there has been interest in assessing the CV adaptations to vigorous exercise. Indeed, exercise can be associated with increases in cardiac biomarkers, though the scope of this observation remains elusive. Interleukin 1 receptor related protein, Suppression of tumorigenicity 2 (ST2) is a biomarker related to the pathophysiology of fibrosis, having shown promise in the study of heart failure. Knowledge of ST2 kinetics could improve understanding of the mechanistic pathways related to CV adaptations to exercise. To assess the current state-of-the-art concerning ST2 levels after exercise in healthy individuals. A systematic review was carried out on three databases (Pubmed, ISI Web of Science and Scopus), up to October 2020, using the queries "ST2" or "ST-2" + "exercise" or "running". A total of six studies were included in the review, encompassing 349 subjects (73% male gender) in which ST2 was assessed. Most studies reported increases in ST2 levels after exercise. Three studies, encompassing a total of 219 individuals, described a cut-off level of 35 ng/dL for ST2. In these, 92.7% of subjects had ST2 levels above this cut-off after exercise (running in all studies). Most studies report increased levels of ST2 after exercise, with an important number of individuals exceeding the 35 ng/dL threshold. Given the small number of individuals represented and the lack of imaging data and long-term follow-up, further prospective larger studies should target this.


Assuntos
Insuficiência Cardíaca , Proteína 1 Semelhante a Receptor de Interleucina-1 , Biomarcadores , Exercício Físico , Feminino , Humanos , Masculino , Prognóstico
14.
J Nurs Manag ; 29(5): 1120-1129, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33426759

RESUMO

AIM: To identify the level of professional empowerment in hospital nurses and describe the relationship between sociodemographic variables and professional empowerment. BACKGROUND: Professional empowerment is positively related to work effectiveness, job satisfaction and organisational and professional commitment. METHOD: Data on professional empowerment were collected by surveying 365 nurses in a Portuguese hospital, with the Portuguese versions of 'Conditions of Work Effectiveness Questionnaire-II' and the 'Psychological Empowerment Instrument'. RESULTS: Overall, psychological empowerment scored 66.2 (standard deviation = 8.9, with 'meaning' scoring highest and 'impact' scoring lowest), whereas structural empowerment scored 18.6 (standard deviation = 3.3, with 'opportunity' and 'informal power' scoring highest and 'resources' scoring lowest). The factor 'age' correlated positively with 'self-determination', 'impact' and 'psychological empowerment', as well as with 'informal power', 'resources' and 'structural empowerment'. Lastly, 'competence' correlated negatively with 'formal power', 'information' and 'structural empowerment'. CONCLUSION: There is a relationship between demographic variables and empowerment, and between structural and psychological empowerment. IMPLICATIONS FOR NURSING MANAGEMENT: Professional empowerment is related to organisational results, so it is important to reinforce and optimize organisational structures. Empowerment can be achieved with access to structures that promote empowerment, particularly resources.


Assuntos
Recursos Humanos de Enfermagem Hospitalar , Recursos Humanos de Enfermagem , Estudos Transversais , Humanos , Satisfação no Emprego , Portugal , Poder Psicológico , Inquéritos e Questionários
15.
BMC Evol Biol ; 20(1): 119, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32933484

RESUMO

BACKGROUND: Many species are threatened with extinction as their population sizes decrease with changing environments or face novel pathogenic threats. A reduction of genetic diversity at major histocompatibility complex (MHC) genes may have dramatic effects on populations' survival, as these genes play a key role in adaptive immunity. This might be the case for chimpanzees, the MHC genes of which reveal signatures of an ancient selective sweep likely due to a viral epidemic that reduced their population size a few million years ago. To better assess how this past event affected MHC variation in chimpanzees compared to humans, we analysed several indexes of genetic diversity and linkage disequilibrium across seven MHC genes on four cohorts of chimpanzees and we compared them to those estimated at orthologous HLA genes in a large set of human populations. RESULTS: Interestingly, the analyses uncovered similar patterns of both molecular diversity and linkage disequilibrium across the seven MHC genes in chimpanzees and humans. Indeed, in both species the greatest allelic richness and heterozygosity were found at loci A, B, C and DRB1, the greatest nucleotide diversity at loci DRB1, DQA1 and DQB1, and both significant global linkage disequilibrium and the greatest proportions of haplotypes in linkage disequilibrium were observed at pairs DQA1 ~ DQB1, DQA1 ~ DRB1, DQB1 ~ DRB1 and B ~ C. Our results also showed that, despite some differences among loci, the levels of genetic diversity and linkage disequilibrium observed in contemporary chimpanzees were globally similar to those estimated in small isolated human populations, in contrast to significant differences compared to large populations. CONCLUSIONS: We conclude, first, that highly conserved mechanisms shaped the diversity of orthologous MHC genes in chimpanzees and humans. Furthermore, our findings support the hypothesis that an ancient demographic decline affecting the chimpanzee populations - like that ascribed to a viral epidemic - exerted a substantial effect on the molecular diversity of their MHC genes, albeit not more pronounced than that experienced by HLA genes in human populations that underwent rapid genetic drift during humans' peopling history. We thus propose a model where chimpanzees' MHC genes regenerated molecular variation through recombination/gene conversion and/or balancing selection after the selective sweep.


Assuntos
Evolução Molecular , Variação Genética , Antígenos HLA-D/genética , Hominidae/genética , Desequilíbrio de Ligação , Pan troglodytes , Alelos , Animais , Frequência do Gene , Genética Populacional , Haplótipos , Humanos , Pan troglodytes/genética
16.
Cardiology ; 145(2): 98-105, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31838463

RESUMO

BACKGROUND: Exercise-based cardiac rehabilitation (EBCR) plays a pivotal role in the management of acute myocardial infarction (AMI). Studies have shown that older individuals have a worse prognosis after an AMI, attesting to the importance of risk reduction strategies. We aimed at assessing the impact of age (patients dichotomized as ≥65 years old or <65 years old) on the functional benefits of an EBCR program among AMI survivors. DESIGN: Observational, retrospective cohort study. PARTICIPANTS: All patients admitted due to an AMI who completed a phase II EBCR program after discharge, between November 2012 and April 2017. INTERVENTION: EBCR program. MEASUREMENTS: Functional parameters were assessed by a symptom-limited cardiopulmonary exercise test. RESULTS: A total of 379 patients were included (30% aged ≥65 years). After the EBCR program, peak oxygen uptake (pVO2) and exercise duration increased significantly. Patients aged ≥65 years presented with more comorbidities and a lower functional capacity. Those aged ≥65 years presented significantly smaller improvements in pVO2 (0.79 ± 2.61 vs. 1.60 ± 3.11 mL/kg/min, p = 0.016) and exercise duration [75 (59-120) vs. 120 s (60-180), p = 0.002]. This was maintained after adjusting for several potential confounders. CONCLUSION: Older patients have a worse functional capacity than their younger counterparts. Still, a contemporary EBCR program was associated with significant functional improvements among those aged ≥65 years. The smaller improvements even after adjustments for potential confounders suggest that physiological differences may contribute to this finding. These results highlight the relevance of EBCR among this higher-risk subgroup.


Assuntos
Reabilitação Cardíaca/métodos , Terapia por Exercício/métodos , Infarto do Miocárdio/reabilitação , Recuperação de Função Fisiológica/fisiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Exercício Físico , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Estudos Retrospectivos , Sobreviventes
17.
J Fish Biol ; 96(1): 74-82, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31648362

RESUMO

We investigated the feeding rates, agonistic behaviour and diet of two blenny species, Entomacrodus vomerinus and Ophioblennius trinitatis, by direct observation and gut content analysis. Both species coexist in small and shallow tide pools in the St Peter and St Paul's Archipelago, equatorial North Atlantic Ocean. The feeding rate of O. trinitatis was c. 55% higher than E. vomerinus. On the other hand, agonistic rate of O. trinitatis was negatively related to body size, whereas in E. vomerinus was positively related. Both species showed a high diet overlap, in which detritus was the most important food item (86% in O. trinitatis and 80% in E. vomerinus). Feeding activity was more intense during the morning for O. trinitatis but afternoon for E. vomerinus. These behavioural observations support the importance of temporal feeding partitioning as the main strategy allowing species co-existence in tide pools.


Assuntos
Comportamento Agonístico , Comportamento Alimentar/fisiologia , Peixes/fisiologia , Animais , Oceano Atlântico , Tamanho Corporal , Dieta , Ilhas
18.
Molecules ; 25(6)2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32168746

RESUMO

Roughly a third of the world's population is estimated to have latent Mycobacterium tuberculosis infection, being at risk of developing active tuberculosis (TB) during their lifetime. Given the inefficacy of prophylactic measures and the increase of drug-resistant M. tuberculosis strains, there is a clear and urgent need for the development of new and more efficient chemotherapeutic agents, with selective toxicity, to be implemented on patient treatment. The component enzymes of the shikimate pathway, which is essential in mycobacteria and absent in humans, stand as attractive and potential targets for the development of new drugs to treat TB. This review gives an update on published work on the enzymes of the shikimate pathway and some insight on what can be potentially explored towards selective drug development.


Assuntos
Antituberculosos/síntese química , Proteínas de Bactérias/antagonistas & inibidores , Inibidores Enzimáticos/síntese química , Regulação Bacteriana da Expressão Gênica , Mycobacterium tuberculosis/efeitos dos fármacos , Ácido Chiquímico/antagonistas & inibidores , Antituberculosos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Humanos , Tuberculose Latente/tratamento farmacológico , Tuberculose Latente/microbiologia , Redes e Vias Metabólicas/efeitos dos fármacos , Redes e Vias Metabólicas/genética , Mycobacterium tuberculosis/enzimologia , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/crescimento & desenvolvimento , Ácido Chiquímico/química , Ácido Chiquímico/metabolismo , Relação Estrutura-Atividade , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/microbiologia
19.
J Phycol ; 55(6): 1370-1385, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31494932

RESUMO

The Southwest Atlantic is notable for having extensive reef areas cemented by nongeniculate coralline red algae. Based on an analysis of four genetic markers and morpho-anatomical features, we clarify the species of Harveylithon in the tropical and warm temperate Southwest Atlantic. Species delimitation methods (mBGD, ABGD, SPN, and PTP), using three markers (psbA, rbcL, and COI), support the recognition of three new species: H. catarinense sp. nov., H. maris-bahiensis sp. nov., and H. riosmenum sp. nov., previously incorrectly called Hydrolithon samoënse. Our findings highlight the importance of using an approach with several lines of evidence to solve the taxonomic status of the cryptic species.


Assuntos
Rodófitas , Brasil , Filogenia
20.
Immunogenetics ; 70(2): 141, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29143073

RESUMO

The above article originally published with an incomplete bibliographic information for Bitarello et al. (2016) and presented correctly in this article.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA