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1.
Mol Biol Evol ; 41(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38376487

RESUMO

The blue whale, Balaenoptera musculus, is the largest animal known to have ever existed, making it an important case study in longevity and resistance to cancer. To further this and other blue whale-related research, we report a reference-quality, long-read-based genome assembly of this fascinating species. We assembled the genome from PacBio long reads and utilized Illumina/10×, optical maps, and Hi-C data for scaffolding, polishing, and manual curation. We also provided long read RNA-seq data to facilitate the annotation of the assembly by NCBI and Ensembl. Additionally, we annotated both haplotypes using TOGA and measured the genome size by flow cytometry. We then compared the blue whale genome with other cetaceans and artiodactyls, including vaquita (Phocoena sinus), the world's smallest cetacean, to investigate blue whale's unique biological traits. We found a dramatic amplification of several genes in the blue whale genome resulting from a recent burst in segmental duplications, though the possible connection between this amplification and giant body size requires further study. We also discovered sites in the insulin-like growth factor-1 gene correlated with body size in cetaceans. Finally, using our assembly to examine the heterozygosity and historical demography of Pacific and Atlantic blue whale populations, we found that the genomes of both populations are highly heterozygous and that their genetic isolation dates to the last interglacial period. Taken together, these results indicate how a high-quality, annotated blue whale genome will serve as an important resource for biology, evolution, and conservation research.


Assuntos
Balaenoptera , Neoplasias , Animais , Balaenoptera/genética , Duplicações Segmentares Genômicas , Genoma , Demografia , Neoplasias/genética
2.
Proc Natl Acad Sci U S A ; 119(51): e2213096119, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36508678

RESUMO

Fungi shape the diversity of life. Characterizing the evolution of fungi is critical to understanding symbiotic associations across kingdoms. In this study, we investigate the genomic and metabolomic diversity of the genus Escovopsis, a specialized parasite of fungus-growing ant gardens. Based on 25 high-quality draft genomes, we show that Escovopsis forms a monophyletic group arising from a mycoparasitic fungal ancestor 61.82 million years ago (Mya). Across the evolutionary history of fungus-growing ants, the dates of origin of most clades of Escovopsis correspond to the dates of origin of the fungus-growing ants whose gardens they parasitize. We reveal that genome reduction, determined by both genomic sequencing and flow cytometry, is a consistent feature across the genus Escovopsis, largely occurring in coding regions, specifically in the form of gene loss and reductions in copy numbers of genes. All functional gene categories have reduced copy numbers, but resistance and virulence genes maintain functional diversity. Biosynthetic gene clusters (BGCs) contribute to phylogenetic differences among Escovopsis spp., and sister taxa in the Hypocreaceae. The phylogenetic patterns of co-diversification among BGCs are similarly exhibited across mass spectrometry analyses of the metabolomes of Escovopsis and their sister taxa. Taken together, our results indicate that Escovopsis spp. evolved unique genomic repertoires to specialize on the fungus-growing ant-microbe symbiosis.


Assuntos
Formigas , Hypocreales , Parasitos , Animais , Formigas/genética , Formigas/microbiologia , Filogenia , Simbiose/genética , Hypocreales/genética
3.
Mol Biol Evol ; 39(9)2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36026509

RESUMO

Evolutionary innovations generate phenotypic and species diversity. Elucidating the genomic processes underlying such innovations is central to understanding biodiversity. In this study, we addressed the genomic basis of evolutionary novelties in the glassy-winged sharpshooter (Homalodisca vitripennis, GWSS), an agricultural pest. Prominent evolutionary innovations in leafhoppers include brochosomes, proteinaceous structures that are excreted and used to coat the body, and obligate symbiotic associations with two bacterial types that reside within cytoplasm of distinctive cell types. Using PacBio long-read sequencing and Dovetail Omni-C technology, we generated a chromosome-level genome assembly for the GWSS and then validated the assembly using flow cytometry and karyotyping. Additional transcriptomic and proteomic data were used to identify novel genes that underlie brochosome production. We found that brochosome-associated genes include novel gene families that have diversified through tandem duplications. We also identified the locations of genes involved in interactions with bacterial symbionts. Ancestors of the GWSS acquired bacterial genes through horizontal gene transfer (HGT), and these genes appear to contribute to symbiont support. Using a phylogenomics approach, we inferred HGT sources and timing. We found that some HGT events date to the common ancestor of the hemipteran suborder Auchenorrhyncha, representing some of the oldest known examples of HGT in animals. Overall, we show that evolutionary novelties in leafhoppers are generated by the combination of acquiring novel genes, produced both de novo and through tandem duplication, acquiring new symbiotic associations that enable use of novel diets and niches, and recruiting foreign genes to support symbionts and enhance herbivory.


Assuntos
Hemípteros , Animais , Evolução Biológica , Genômica , Hemípteros/genética , Proteômica , Simbiose/genética
4.
Phys Rev Lett ; 131(10): 102502, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37739382

RESUMO

The absolute scale of the neutrino mass plays a critical role in physics at every scale, from the subatomic to the cosmological. Measurements of the tritium end-point spectrum have provided the most precise direct limit on the neutrino mass scale. In this Letter, we present advances by Project 8 to the cyclotron radiation emission spectroscopy (CRES) technique culminating in the first frequency-based neutrino mass limit. With only a cm^{3}-scale physical detection volume, a limit of m_{ß}<155 eV/c^{2} (152 eV/c^{2}) is extracted from the background-free measurement of the continuous tritium beta spectrum in a Bayesian (frequentist) analysis. Using ^{83m}Kr calibration data, a resolution of 1.66±0.19 eV (FWHM) is measured, the detector response model is validated, and the efficiency is characterized over the multi-keV tritium analysis window. These measurements establish the potential of CRES for a high-sensitivity next-generation direct neutrino mass experiment featuring low background and high resolution.

5.
Phys Rev Lett ; 131(16): 162501, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37925694

RESUMO

Neutrinoless double beta decay (0νßß) is a yet unobserved nuclear process that would demonstrate Lepton number violation, a clear evidence of beyond standard model physics. The process two neutrino double beta decay (2νßß) is allowed by the standard model and has been measured in numerous experiments. In this Letter, we report a measurement of 2νßß decay half-life of ^{100}Mo to the ground state of ^{100}Ru of [7.07±0.02(stat)±0.11(syst)]×10^{18} yr by the CUPID-Mo experiment. With a relative precision of ±1.6% this is the most precise measurement to date of a 2νßß decay rate in ^{100}Mo. In addition, we constrain higher-order corrections to the spectral shape, which provides complementary nuclear structure information. We report a novel measurement of the shape factor ξ_{3,1}=0.45±0.03(stat)±0.05(syst) based on a constraint on the ratio of higher-order terms from theory, which can be reliably calculated. This is compared to theoretical predictions for different nuclear models. We also extract the first value for the effective axial vector coupling constant obtained from a spectral shape study of 2νßß decay.

6.
Phys Rev Lett ; 126(18): 181802, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-34018798

RESUMO

The CUPID-Mo experiment at the Laboratoire Souterrain de Modane (France) is a demonstrator for CUPID, the next-generation ton-scale bolometric 0νßß experiment. It consists of a 4.2 kg array of 20 enriched Li_{2}^{100}MoO_{4} scintillating bolometers to search for the lepton-number-violating process of 0νßß decay in ^{100}Mo. With more than one year of operation (^{100}Mo exposure of 1.17 kg×yr for physics data), no event in the region of interest and, hence, no evidence for 0νßß is observed. We report a new limit on the half-life of 0νßß decay in ^{100}Mo of T_{1/2}>1.5×10^{24} yr at 90% C.I. The limit corresponds to an effective Majorana neutrino mass ⟨m_{ßß}⟩<(0.31-0.54) eV, dependent on the nuclear matrix element in the light Majorana neutrino exchange interpretation.

7.
Ecol Appl ; 31(8): e02431, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34339067

RESUMO

Implementation of wildfire- and climate-adaptation strategies in seasonally dry forests of western North America is impeded by numerous constraints and uncertainties. After more than a century of resource and land use change, some question the need for proactive management, particularly given novel social, ecological, and climatic conditions. To address this question, we first provide a framework for assessing changes in landscape conditions and fire regimes. Using this framework, we then evaluate evidence of change in contemporary conditions relative to those maintained by active fire regimes, i.e., those uninterrupted by a century or more of human-induced fire exclusion. The cumulative results of more than a century of research document a persistent and substantial fire deficit and widespread alterations to ecological structures and functions. These changes are not necessarily apparent at all spatial scales or in all dimensions of fire regimes and forest and nonforest conditions. Nonetheless, loss of the once abundant influence of low- and moderate-severity fires suggests that even the least fire-prone ecosystems may be affected by alteration of the surrounding landscape and, consequently, ecosystem functions. Vegetation spatial patterns in fire-excluded forested landscapes no longer reflect the heterogeneity maintained by interacting fires of active fire regimes. Live and dead vegetation (surface and canopy fuels) is generally more abundant and continuous than before European colonization. As a result, current conditions are more vulnerable to the direct and indirect effects of seasonal and episodic increases in drought and fire, especially under a rapidly warming climate. Long-term fire exclusion and contemporaneous social-ecological influences continue to extensively modify seasonally dry forested landscapes. Management that realigns or adapts fire-excluded conditions to seasonal and episodic increases in drought and fire can moderate ecosystem transitions as forests and human communities adapt to changing climatic and disturbance regimes. As adaptation strategies are developed, evaluated, and implemented, objective scientific evaluation of ongoing research and monitoring can aid differentiation of warranted and unwarranted uncertainties.


Assuntos
Incêndios , Incêndios Florestais , Ecossistema , Florestas , Humanos , América do Norte
8.
Epidemiol Infect ; 149: e36, 2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33509318

RESUMO

This paper describes the epidemiology of coronavirus disease 2019 (COVID-19) in Northern Ireland (NI) between 26 February 2020 and 26 April 2020, and analyses enhanced surveillance and contact tracing data collected between 26 February 2020 and 13 March 2020 to estimate secondary attack rates (SAR) and relative risk of infection among different categories of contacts of individuals with laboratory confirmed severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection. Our results show that during the study period COVID-19 cumulative incidence and mortality was lower in NI than the rest of the UK. Incidence and mortality were also lower than in the Republic of Ireland (ROI), although these observed differences are difficult to interpret given considerable differences in testing and surveillance between the two nations. SAR among household contacts was 15.9% (95% CI 6.6%-30.1%), over 6 times higher than the SAR among 'high-risk' contacts at 2.5% (95% CI 0.9%-5.4%). The results from logistic regression analysis of testing data on contacts of laboratory-confirmed cases show that household contacts had 11.0 times higher odds (aOR: 11.0, 95% CI 1.7-70.03, P-value: 0.011) of testing positive for SARS-CoV-2 compared to other categories of contacts. These results demonstrate the importance of the household as a locus of SARS-CoV-2 transmission, and the urgency of identifying effective interventions to reduce household transmission.


Assuntos
COVID-19/epidemiologia , SARS-CoV-2 , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Busca de Comunicante , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Irlanda do Norte/epidemiologia , Vigilância da População , Adulto Jovem
9.
BMC Biol ; 18(1): 70, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32560686

RESUMO

BACKGROUND: Fleas (Insecta: Siphonaptera) are small flightless parasites of birds and mammals; their blood-feeding can transmit many serious pathogens (i.e., the etiological agents of bubonic plague, endemic and murine typhus). The lack of flea genome assemblies has hindered research, especially comparisons to other disease vectors. Accordingly, we sequenced the genome of the cat flea, Ctenocephalides felis, an insect with substantial human health and veterinary importance across the globe. RESULTS: By combining Illumina and PacBio sequencing of DNA derived from multiple inbred female fleas with Hi-C scaffolding techniques, we generated a chromosome-level genome assembly for C. felis. Unexpectedly, our assembly revealed extensive gene duplication across the entire genome, exemplified by ~ 38% of protein-coding genes with two or more copies and over 4000 tRNA genes. A broad range of genome size determinations (433-551 Mb) for individual fleas sampled across different populations supports the widespread presence of fluctuating copy number variation (CNV) in C. felis. Similarly, broad genome sizes were also calculated for individuals of Xenopsylla cheopis (Oriental rat flea), indicating that this remarkable "genome-in-flux" phenomenon could be a siphonapteran-wide trait. Finally, from the C. felis sequence reads, we also generated closed genomes for two novel strains of Wolbachia, one parasitic and one symbiotic, found to co-infect individual fleas. CONCLUSION: Rampant CNV in C. felis has dire implications for gene-targeting pest control measures and stands to complicate standard normalization procedures utilized in comparative transcriptomics analysis. Coupled with co-infection by novel Wolbachia endosymbionts-potential tools for blocking pathogen transmission-these oddities highlight a unique and underappreciated disease vector.


Assuntos
Ctenocephalides/genética , Variações do Número de Cópias de DNA , Duplicação Gênica , Tamanho do Genoma , Animais , Cromossomos , Feminino , Masculino
10.
Occup Med (Lond) ; 71(4-5): 189-195, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-33963871

RESUMO

BACKGROUND: Presenteeism among nurses is the common behaviour of being physically present at work when one should not be due to personal health and well-being, a stressful work environment, lack of work-life balance, or a sense of professional identity or obligation. AIMS: To explore nurses' decision-making process related to presenteeism in a large Hong Kong public hospital. METHODS: As part of a larger study on nurse presenteeism in Hong Kong, we conducted focus groups with nurses to understand their considerations related to working sick. RESULTS: Eleven major themes emerged from the focus groups, which we grouped into three organizational domains reflecting nurses' decision-making process around presenteeism: consideration for colleagues, organizational factors and professional identity. CONCLUSIONS: Presenteeism was a familiar behaviour among Hong Kong nurses in our study. We found both overlap and divergence with prior presenteeism research in the domains and themes identified. Loyalty to colleagues, written and unwritten rules and professional identity as nurses all seemed to encourage presenteeism among Hong Kong nurses. Organizations seeking to discourage presenteeism should evaluate policies such as sick leave certificates, ensure appropriate coverage for all nurse ranks and address subcultural norms encouraging presenteeism.


Assuntos
Enfermeiras e Enfermeiros , Presenteísmo , Hong Kong , Hospitais Públicos , Humanos , Local de Trabalho
11.
BMC Genomics ; 21(1): 227, 2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32171258

RESUMO

BACKGROUND: Halyomorpha halys (Stål), the brown marmorated stink bug, is a highly invasive insect species due in part to its exceptionally high levels of polyphagy. This species is also a nuisance due to overwintering in human-made structures. It has caused significant agricultural losses in recent years along the Atlantic seaboard of North America and in continental Europe. Genomic resources will assist with determining the molecular basis for this species' feeding and habitat traits, defining potential targets for pest management strategies. RESULTS: Analysis of the 1.15-Gb draft genome assembly has identified a wide variety of genetic elements underpinning the biological characteristics of this formidable pest species, encompassing the roles of sensory functions, digestion, immunity, detoxification and development, all of which likely support H. halys' capacity for invasiveness. Many of the genes identified herein have potential for biomolecular pesticide applications. CONCLUSIONS: Availability of the H. halys genome sequence will be useful for the development of environmentally friendly biomolecular pesticides to be applied in concert with more traditional, synthetic chemical-based controls.


Assuntos
Heterópteros/genética , Proteínas de Insetos/genética , Resistência a Inseticidas , Sequenciamento Completo do Genoma/métodos , Animais , Ecossistema , Transferência Genética Horizontal , Tamanho do Genoma , Heterópteros/classificação , Espécies Introduzidas , Filogenia
12.
Proc Biol Sci ; 287(1935): 20201388, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32993470

RESUMO

The structure of a genome can be described at its simplest by the number of chromosomes and the sex chromosome system it contains. Despite over a century of study, the evolution of genome structure on this scale remains recalcitrant to broad generalizations that can be applied across clades. To address this issue, we have assembled a dataset of 823 karyotypes from the insect group Polyneoptera. This group contains orders with a range of variations in chromosome number, and offer the opportunity to explore the possible causes of these differences. We have analysed these data using both phylogenetic and taxonomic approaches. Our analysis allows us to assess the importance of rates of evolution, phylogenetic history, sex chromosome systems, parthenogenesis and genome size on variation in chromosome number within clades. We find that fusions play a key role in the origin of new sex chromosomes, and that orders exhibit striking differences in rates of fusions, fissions and polyploidy. Our results suggest that the difficulty in finding consistent rules that govern evolution at this scale may be due to the presence of many interacting forces that can lead to variation among groups.


Assuntos
Evolução Molecular , Insetos , Cromossomos Sexuais , Animais , Feminino , Tamanho do Genoma , Cariótipo , Partenogênese , Filogenia , Poliploidia
13.
Epidemiol Infect ; 148: e15, 2020 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-32014080

RESUMO

Yukon Territory (YT) is a remote region in northern Canada with ongoing spread of tuberculosis (TB). To explore the utility of whole genome sequencing (WGS) for TB surveillance and monitoring in a setting with detailed contact tracing and interview data, we used a mixed-methods approach. Our analysis included all culture-confirmed cases in YT (2005-2014) and incorporated data from 24-locus Mycobacterial Interspersed Repetitive Units-Variable Number of Tandem Repeats (MIRU-VNTR) genotyping, WGS and contact tracing. We compared field-based (contact investigation (CI) data + MIRU-VNTR) and genomic-based (WGS + MIRU-VNTR + basic case data) investigations to identify the most likely source of each person's TB and assessed the knowledge, attitudes and practices of programme personnel around genotyping and genomics using online, multiple-choice surveys (n = 4) and an in-person group interview (n = 5). Field- and genomics-based approaches agreed for 26 of 32 (81%) cases on likely location of TB acquisition. There was less agreement in the identification of specific source cases (13/22 or 59% of cases). Single-locus MIRU-VNTR variants and limited genetic diversity complicated the analysis. Qualitative data indicated that participants viewed genomic epidemiology as a useful tool to streamline investigations, particularly in differentiating latent TB reactivation from the recent transmission. Based on this, genomic data could be used to enhance CIs, focus resources, target interventions and aid in TB programme evaluation.


Assuntos
Busca de Comunicante/métodos , Epidemiologia Molecular/métodos , Tipagem Molecular/métodos , Mycobacterium/classificação , Mycobacterium/genética , Tuberculose/epidemiologia , Sequenciamento Completo do Genoma/métodos , Transmissão de Doença Infecciosa , Genótipo , Humanos , Mycobacterium/isolamento & purificação , Tuberculose/transmissão , Yukon/epidemiologia
14.
BMC Health Serv Res ; 20(1): 341, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32316963

RESUMO

BACKGROUND: The End TB Strategy calls for global scale-up of preventive treatment for latent tuberculosis infection (LTBI), but little information is available about the associated human resource requirements. Our study aimed to quantify the healthcare worker (HCW) time needed to perform the tasks associated with each step along the LTBI cascade of care for household contacts of TB patients. METHODS: We conducted a time and motion (TAM) study between January 2018 and March 2019, in which consenting HCWs were observed throughout a typical workday. The precise time spent was recorded in pre-specified categories of work activities for each step along the cascade. A linear mixed model was fit to estimate the time at each step. RESULTS: A total of 173 HCWs in Benin, Canada, Ghana, Indonesia, and Vietnam participated. The greatest amount of time was spent for the medical evaluation (median: 11 min; IQR: 6-16), while the least time was spent on reading a tuberculin skin test (TST) (median: 4 min; IQR: 2-9). The greatest variability was seen in the time spent for each medical evaluation, while TST placement and reading showed the least variability. The total time required to complete all steps along the LTBI cascade, from identification of household contacts (HHC) through to treatment initiation ranged from 1.8 h per index TB patient in Vietnam to 5.2 h in Ghana. CONCLUSIONS: Our findings suggest that the time requirements are very modest to perform each step in the latent TB cascade of care, but to achieve full identification and management of all household contacts will require additional human resources in many settings.


Assuntos
Administração de Caso , Pessoal de Saúde , Recursos em Saúde , Tuberculose Latente , Adulto , Benin , Canadá , Feminino , Gana , Humanos , Indonésia , Tuberculose Latente/diagnóstico , Tuberculose Latente/terapia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Estudos de Tempo e Movimento , Vietnã
15.
Hemoglobin ; 44(3): 174-178, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32552204

RESUMO

Hb Bronovo [α103(G10)His→Leu, HBA2: c.311A>T] is an α-globin variant that interferes with and decreases binding efficiency to α hemoglobin (Hb) stabilizing protein (AHSP), a chaperone molecule. The histidine residue at position 103 is integral to the AHSP hydrogen bond formation where disruption results in an increased quantity of cytotoxic free α-globin chains, thereby creating a similar pathophysiology as ß-thalassemia (ß-thal). We report a family with Hb Bronovo, including a homozygous proband, which resulted from maternal uniparental disomy (UPD). Although not detected by routine studies in previous reports, the variant protein is visible by intact mass spectrometry (MS).


Assuntos
Alelos , Hemoglobinas Anormais/genética , Homozigoto , Mutação , alfa-Globinas/genética , Talassemia alfa/diagnóstico , Talassemia alfa/genética , Substituição de Aminoácidos , Pré-Escolar , Mapeamento Cromossômico , Análise Mutacional de DNA , Feminino , Testes Genéticos , Heterozigoto , Humanos , Padrões de Herança , Masculino , Herança Materna , Linhagem
16.
Heredity (Edinb) ; 122(5): 558-569, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30315219

RESUMO

Intraspecific variation maintained in natural populations has long intrigued scientists and naturalists. One form of this variation, color polymorphisms, provide a rich opportunity to connect genotypic and phenotypic diversity within an ecological and evolutionary context. The existence of color polymorphisms in Panamanian populations of the Neotropical tortoise beetle, Chelymorpha alternans, has been suspected but never systematically explored. To characterize geographic distribution and underlying genetics we sampled a total of 3819 beetles from 28 sites across Panama, quantifying five distinct phenotypes. Two phenotypes, the "metallic" and "rufipennis" are the most widely distributed phenotypes, occurring in nearly all collecting sites. The "veraguensis" phenotype was found to be restricted to the Western end of the Isthmus and the "militaris" phenotypes restricted to sites east of the canal. Controlled matings between phenotypes and reared offspring revealed no indications of reproductive barriers, even among phenotypes which do not co-occur in nature. Color pattern phenotype is largely controlled by Mendelian assortment of four alleles competing at a single locus. A clear dominance hierarchy exists among alleles, with two being co-dominant. Genomic scans from 32 individuals revealed low levels of genetic differentiation, with a small fraction of the genome showing a high degree of divergence. The easily observed variation among populations, simple genetic architecture, and rearing capabilities, make this a promising system for investigating proximate and ultimate factors of phenotypic variation.


Assuntos
Besouros/genética , Pigmentação/genética , Animais , Evolução Biológica , Feminino , Loci Gênicos , Tamanho do Genoma , Genoma de Inseto/genética , Genótipo , Masculino , Panamá , Fenótipo , Filogeografia , Polimorfismo Genético
17.
Epidemiol Infect ; 147: e188, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-31364521

RESUMO

Few studies have used genomic epidemiology to understand tuberculosis (TB) transmission in rural and remote settings - regions often unique in history, geography and demographics. To improve our understanding of TB transmission dynamics in Yukon Territory (YT), a circumpolar Canadian territory, we conducted a retrospective analysis in which we combined epidemiological data collected through routine contact investigations with clinical and laboratory results. Mycobacterium tuberculosis isolates from all culture-confirmed TB cases in YT (2005-2014) were genotyped using 24-locus Mycobacterial Interspersed Repetitive Units-Variable Number of Tandem Repeats (MIRU-VNTR) and compared to each other and to those from the neighbouring province of British Columbia (BC). Whole genome sequencing (WGS) of genotypically clustered isolates revealed three sustained transmission networks within YT, two of which also involved BC isolates. While each network had distinct characteristics, all had at least one individual acting as the probable source of three or more culture-positive cases. Overall, WGS revealed that TB transmission dynamics in YT are distinct from patterns of spread in other, more remote Northern Canadian regions, and that the combination of WGS and epidemiological data can provide actionable information to local public health teams.


Assuntos
Genoma Bacteriano , Mycobacterium tuberculosis/genética , Tuberculose/transmissão , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Colúmbia Britânica , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Repetições Minissatélites , Tuberculose/microbiologia , Sequenciamento Completo do Genoma , Adulto Jovem , Yukon
18.
J Hered ; 110(2): 219-228, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30476187

RESUMO

Genome sizes are known to vary between closely related species, but the patterns behind this variation have yet to be fully understood. Although this variation has been evaluated between species and within sexes, unknown is the extent to which this variation is driven by differentiation in sex chromosomes. To address this longstanding question, we examine the mode and tempo of genome size evolution for a total of 87 species of Drosophilidae, estimating and updating male genome size values for 44 of these species. We compare the evolution of genome size within each sex to the evolution of the differences between the sexes. Utilizing comparative phylogenetic methods, we find that male and female genome size evolution is largely a neutral process, reflective of phylogenetic relatedness between species, which supports the newly proposed accordion model for genome size change. When similarly analyzed, the difference between the sexes due to heteromorphic sex chromosomes is a dynamic process; the male-female genome size difference increases with time with or without known neo-Y events or complete loss of the Y. Observed instances of rapid change match theoretical expectations and known neo-Y and Y loss events in individual species.


Assuntos
Drosophila/genética , Evolução Molecular , Tamanho do Genoma , Genoma , Genômica , Animais , Bases de Dados Genéticas , Drosophila/classificação , Feminino , Genômica/métodos , Masculino , Filogenia , Cromossomos Sexuais , Fatores Sexuais
19.
Eur Arch Otorhinolaryngol ; 276(8): 2293-2300, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31187240

RESUMO

PURPOSE: This study examined the incidence and risk factors for vocal fold fixation due to proximal progression of idiopathic subglottic stenosis (ISS) over the course of serial treatments. METHODS: Records of 22 consecutive patients with ISS treated between 2004 and 2016 were retrospectively reviewed. Patient, stenosis, and treatment details were recorded. Cox regression was used to identify independent predictors of vocal fold fixation. RESULTS: All patients were female and mean age at diagnosis was 46 ± 7 years. In five patients, the stenosis was within 15 mm of the glottis at first treatment. Vocal fold fixation due to proximal stenosis progression occurred in seven (32%) patients. It led to permanent hoarseness due to unilateral vocal fold fixation in two patients and caused airway compromise due to bilateral vocal fixation in two other patients. No airway-related deaths occurred and no patient required a tracheostomy. Stenosis incision using coblation or potassium titanyl phosphate laser, and an initial glottis-to-stenosis (GtS) distance < 15 mm significantly increased the risk of proximal stenosis progression on univariable analysis. CONCLUSION: Vocal fold fixation due to proximal stenosis progression is a significant complication of idiopathic subglottic stenosis and causes permanent voice and/or airway sequelae. It should be actively looked for and documented every time a patient is assessed. If a reduction in the GtS distance is observed, definitive surgery should be promptly considered before proximal stenosis progression compromises the efficacy and safety of definitive treatment or, worse, causes vocal fold fixation.


Assuntos
Laringoestenose/complicações , Laringoestenose/patologia , Procedimentos de Cirurgia Plástica , Prega Vocal/patologia , Prega Vocal/cirurgia , Adulto , Constrição Patológica/cirurgia , Progressão da Doença , Feminino , Glote/cirurgia , Rouquidão/etiologia , Humanos , Laringoestenose/cirurgia , Lasers de Estado Sólido , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
20.
Clin Genet ; 93(5): 1022-1029, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29383714

RESUMO

This study examined the impact of disclosing subclassifications of genetic variants of uncertain significance (VUS) on behavioral intentions. We studied return of VUS results to 79 individuals with a cardiomyopathy-associated VUS, subclassified into VUS-high or VUS-low. Primary outcomes were perceived risk (absolute and comparative), perceived severity, perceived value of information, self-efficacy, decision regret, and behavioral intentions to share results and change behaviors. There was no significant difference between the 2 subclasses in overall behavioral intentions (t = 0.023, P = .982) and each of the individual items on the behavioral intentions scale; absolute (t = -1.138, P = .259) or comparative (t = -0.463, P = .645) risk perceptions; perceived value of information (t = 0.582, P = .563) and self-efficacy (t = -0.733, P = .466). Decision regret was significantly different (t = 2.148, P = .035), with VUS-low (mean = 17.24, SD = 16.08) reporting greater regret. Combining the subclasses, perceived value of information was the strongest predictor of behavioral intentions (ß = 0.524, P < .001). Participants generally understood the meaning of a genetic VUS result classification and reported satisfaction with result disclosure. No differences in behavioral intentions were found, but differences in decision regret suggest participants distinguish subclasses of VUS results. The perceived value of VUS may motivate recipients to pursue health-related behaviors.


Assuntos
Cardiomiopatias/genética , Exoma/genética , Predisposição Genética para Doença , Cardiomiopatias/fisiopatologia , Feminino , Aconselhamento Genético , Testes Genéticos , Variação Genética , Humanos , Masculino , Análise de Sequência de DNA , Incerteza
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