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1.
Curr Biol ; 34(7): 1469-1478.e6, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38490202

RESUMO

The global panzootic lineage (GPL) of the pathogenic fungus Batrachochytrium dendrobatidis (Bd) has caused severe amphibian population declines, yet the drivers underlying the high frequency of GPL in regions of amphibian decline are unclear. Using publicly available Bd genome sequences, we identified multiple non-GPL Bd isolates that contain a circular Rep-encoding single-stranded (CRESS)-like DNA virus, which we named Bd DNA virus 1 (BdDV-1). We further sequenced and constructed genome assemblies with long read sequences to find that the virus is integrated into the nuclear genome in some strains. Attempts to cure virus-positive isolates were unsuccessful; however, phenotypic differences between naturally virus-positive and virus-negative Bd isolates suggested that BdDV-1 decreases the growth of its host in vitro but increases the virulence of its host in vivo. BdDV-1 is the first-described CRESS DNA mycovirus of zoosporic true fungi, with a distribution inversely associated with the emergence of the panzootic lineage.


Assuntos
Quitridiomicetos , Micoses , Animais , Virulência/genética , Quitridiomicetos/genética , Micoses/microbiologia , Anfíbios/microbiologia , Genótipo , Vírus de DNA
2.
mBio ; 14(4): e0131323, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37486265

RESUMO

Environmental DNA analyses of fungal communities typically reveal a much larger diversity than can be ascribed to known species. Much of this hidden diversity lies within undescribed fungal lineages, especially the early diverging fungi (EDF). Although these EDF often represent new lineages even at the phylum level, they have never been cultured, making their morphology and ecology uncertain. One of the methods to characterize these uncultured fungi is a single-cell DNA sequencing approach. In this study, we established a large data set of single-cell sequences of EDF by manually isolating and photographing parasitic fungi on various hosts such as algae, protists, and micro-invertebrates, combined with subsequent long-read sequencing of the ribosomal DNA locus (rDNA). We successfully obtained rDNA sequences of 127 parasitic fungal cells, which clustered into 71 phylogenetic lineages belonging to seven phylum-level clades of EDF: Blastocladiomycota, Chytridiomycota, Aphelidiomycota, Rozellomycota, and three unknown phylum-level clades. Most of our single cells yielded novel sequences distinguished from both described taxa and existing metabarcoding data, indicating an expansive and hidden diversity of parasitic taxa of EDF. We also revealed an unexpected diversity of endobiotic Olpidium-like chytrids and hyper-parasitic lineages. Overall, by combining photographs of parasitic fungi with phylogenetic analyses, we were able to better understand the ecological function and morphology of many of the branches on the fungal tree of life known only from DNA sequences. IMPORTANCE Much of the diversity of microbes from natural habitats, such as soil and freshwater, comprise species and lineages that have never been isolated into pure culture. In part, this stems from a bias of culturing in favor of saprotrophic microbes over the myriad symbiotic ones that include parasitic and mutualistic relationships with other taxa. In the present study, we aimed to shed light on the ecological function and morphology of the many undescribed lineages of aquatic fungi by individually isolating and sequencing molecular barcodes from 127 cells of host-associated fungi using single-cell sequencing. By adding these sequences and their photographs into the fungal tree, we were able to understand the morphology of reproductive and vegetative structures of these novel fungi and to provide a hypothesized ecological function for them. These individual host-fungal cells revealed themselves to be complex environments despite their small size; numerous samples were hyper-parasitized with other zoosporic fungal lineages such as Rozellomycota.


Assuntos
Quitridiomicetos , Microscopia , Filogenia , Fungos , Quitridiomicetos/genética , DNA Ribossômico/genética , Água Doce/microbiologia , DNA Fúngico/genética , DNA Fúngico/química
3.
Mol Phylogenet Evol ; 180: 107706, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36657624

RESUMO

The Chytridiomycota is a phylum of zoosporic eufungi that inhabit terrestrial, freshwater, and oceanic habitats. Within the phylum, the Rhizophydiales contains several monotypic families theorized to hold a diverse assemblage of fungi yet to be discovered and properly described. Based on morphology alone, many species in this order are difficult or impossible to identify. In this study, we isolated three chytrids from northern Thailand. Phylogenetic analyses placed the isolates in three monotypic genera within Rhizophydiales. Intrageneric genetic distances in the internal transcribed spacer (ITS) ranged between 1.5 and 8.5%. Angulomyces solicola sp. nov. is characterized by larger sporangia, spores, and fewer discharge papilla than A.argentinensis; Gorgonomyces thailandicus sp. nov. has larger zoospores and fewer discharge papillae in culture compared to G. haynaldii; Terramyces chiangraiensis sp. nov. produces larger sporangia than T. subangulosum. We delimited species of Angulomyces, Gorgonomyces and Terramyces using a tripartite approach that employed phylogeny, ITS genetic distances and Poisson tree processes (PTP). Results of these approaches suggest more than one species in each genus. This study contributes to the knowledge of chytrids, an understudied group in Thailand and worldwide.


Assuntos
Quitridiomicetos , Humanos , Filogenia , Tailândia , DNA Fúngico/genética , Quitridiomicetos/genética , Água Doce
4.
Proc Natl Acad Sci U S A ; 119(36): e2116841119, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-36037379

RESUMO

Most of the described species in kingdom Fungi are contained in two phyla, the Ascomycota and the Basidiomycota (subkingdom Dikarya). As a result, our understanding of the biology of the kingdom is heavily influenced by traits observed in Dikarya, such as aerial spore dispersal and life cycles dominated by mitosis of haploid nuclei. We now appreciate that Fungi comprises numerous phylum-level lineages in addition to those of Dikarya, but the phylogeny and genetic characteristics of most of these lineages are poorly understood due to limited genome sampling. Here, we addressed major evolutionary trends in the non-Dikarya fungi by phylogenomic analysis of 69 newly generated draft genome sequences of the zoosporic (flagellated) lineages of true fungi. Our phylogeny indicated five lineages of zoosporic fungi and placed Blastocladiomycota, which has an alternation of haploid and diploid generations, as branching closer to the Dikarya than to the Chytridiomyceta. Our estimates of heterozygosity based on genome sequence data indicate that the zoosporic lineages plus the Zoopagomycota are frequently characterized by diploid-dominant life cycles. We mapped additional traits, such as ancestral cell-cycle regulators, cell-membrane- and cell-wall-associated genes, and the use of the amino acid selenocysteine on the phylogeny and found that these ancestral traits that are shared with Metazoa have been subject to extensive parallel loss across zoosporic lineages. Together, our results indicate a gradual transition in the genetics and cell biology of fungi from their ancestor and caution against assuming that traits measured in Dikarya are typical of other fungal lineages.


Assuntos
Fungos , Estágios do Ciclo de Vida , Filogenia , Diploide , Fungos/classificação , Fungos/genética , Genoma Fúngico/genética
5.
Behav Res Methods ; 54(5): 2479-2501, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35018608

RESUMO

This paper describes a smart tablet-based drawing app to digitally record participants' engagement with the Rey-Osterrieth complex figure (ROCF) task, a well-characterised perceptual memory task that assesses local and global memory. Digitisation of the tasks allows for improved ecological validity, especially in children attracted to tablet devices. Further, digital translation of the tasks affords new measures, including accuracy and computation of the fine motor control kinematics employed to carry out the drawing Here, we report a feasibility study to test the relationship between two neurodevelopmental conditions: autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD). The smart tablet app was employed with 39 adult participants (18-35) characterised for autistic and ADHD traits, and scored using the ROCF perceptual and organisational scoring systems. Trait scores and conditions were predictor variables in linear regression models. Positive correlations were found between the attention-to-detail, attention-switching and communication subscales of the autistic trait questionnaire and organisational scores on the ROCF task. These findings suggest that autistic traits might be linked to differential performance on the ROCF task. Novelty and future applications of the app are discussed.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Transtorno Autístico , Aplicativos Móveis , Criança , Adulto , Humanos , Testes Neuropsicológicos
6.
BJOG ; 129(5): 708-721, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34559946

RESUMO

OBJECTIVE: We aimed to explore: (i) the association of sedentary time (ST) and physical activity (PA) during pregnancy with the placental expression of genes related to glucose and lipid metabolism in pregnant women who are obese; (ii) maternal metabolic factors mediating changes in these placental transcripts; and (iii) cord blood markers related to the mRNAs mediating neonatal adiposity. DESIGN: Multicentre randomised controlled trial. SETTING: Hospitals in nine European countries. POPULATION: A cohort of 112 pregnant women with placental tissue. METHODS: Both ST and moderate-to-vigorous PA (MVPA) levels were measured objectively using accelerometry at three time periods during pregnancy. MAIN OUTCOME MEASURES: Placental mRNAs (FATP2, FATP3, FABP4, GLUT1 and PPAR-γ) were measured with NanoString technology. Maternal and fetal metabolic markers and neonatal adiposity were assessed. RESULTS: Longer periods of ST, especially in early to middle pregnancy, was associated with lower placental FATP2 and FATP3 expression (P < 0.05), whereas MVPA at baseline was inversely associated with GLUT1 mRNA (P = 0.02). Although placental FATP2 and FATP3 expression were regulated by the insulin-glucose axis (P < 0.05), no maternal metabolic marker mediated the association of ST/MVPA with placental mRNAs (P > 0.05). Additionally, placental FATP2 expression was inversely associated with cord blood triglycerides and free fatty acids (FFAs; P < 0.01). No cord blood marker mediated neonatal adiposity except for cord blood leptin, which mediated the effects of PPAR-γ on neonatal sum of skinfolds (P < 0.05). CONCLUSIONS: In early to middle pregnancy, ST is associated with the expression of placental genes linked to lipid transport. PA is hardly related to transporter mRNAs. Strategies aimed at reducing sedentary behaviour during pregnancy could modulate placental gene expression, which may help to prevent unfavourable fetal and maternal pregnancy outcomes. TWEETABLE ABSTRACT: Reducing sedentary behaviour in pregnancy might modulate placental expression of genes related to lipid metabolism in women who are obese.


Assuntos
Glucose , Comportamento Sedentário , Exercício Físico , Feminino , Humanos , Recém-Nascido , Estilo de Vida , Metabolismo dos Lipídeos/genética , Obesidade/complicações , Placenta/metabolismo , Gravidez , Resultado da Gravidez , Gestantes , RNA Mensageiro
7.
Aust Dent J ; 66(4): 397-405, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34152019

RESUMO

BACKGROUND: As part of a larger study, the Crossroads-II Dental sub-study determined the patterns of, and barriers to, oral health care service utilization in a rural area of Victoria. METHODS: In this cross-sectional sub-study predisposing, enabling, needs-related, and oral health variables were considered in association with patterns of oral health care utilization. A logistic regression was performed to explain the use of oral health care services. RESULTS: Overall, 574 adults participated, with 50.9% reporting having visited an oral health care service in the previous 12 months. Age, number of chronic health conditions and holding a health card; were associated with increased visit to a dentist (OR = 1.01; 95% CI: 1.00-1.03; OR = 1.08; 95% CI: 1.01-1.16; OR = 2.06; 95% CI: 1.26-3.36, respectively). Perceived barriers to care and number of missing teeth decreased the odds of using services (OR = 0.46; 95% CI: 0.36-0.58; OR = 0.95; 95% CI: 0.92-0.98, respectively). CONCLUSIONS: Results suggest that use of oral health care services is associated with a range of financial, educational, health and structural barriers. Increasing the use of oral health care services in rural populations requires additional efforts beyond the reduction of financial barriers.


Assuntos
Serviços de Saúde Bucal , População Rural , Adulto , Austrália , Estudos Transversais , Assistência Odontológica , Acessibilidade aos Serviços de Saúde , Humanos , Saúde Bucal , Aceitação pelo Paciente de Cuidados de Saúde
8.
Mycologia ; 113(3): 684-690, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33847227

RESUMO

Molecular and ultrastructural investigations of the Chytridiomycota during the last 20 years have led to the separation of new orders, including the Rhizophydiales. Most species in this order are morphologically similar, possessing monocentric, eucarpic, spherical thalli. Here, based on analysis of nuc 18S and 28S rDNA, we add the new genus and species Polyrhizophydium stewartii to the order. This saprobe of moribund aquatic plant leaves is the first known rhizomycelial species in the order. In our molecular phylogeny, P. stewartii groups with the amphibian pathogens Batrachochytriuim dendrobatidis and B. salamandrivorans, making it of particular interest to investigators studying evolutionary pathways associated with host-switching and morphological adaptation.


Assuntos
Batrachochytrium , Quitridiomicetos , Quitridiomicetos/genética , DNA Ribossômico/genética , Filogenia
9.
QJM ; 114(8): 553-558, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-32589708

RESUMO

BACKGROUND: Runt-related transcription factor 1 (RUNX1T1) isoforms are involved in adipogenesis. RUNX1T1 is mediated by the fat mass and obesity-associated (FTO). However, the extent to which RUNX1T1 single-nucleotide polymorphisms (SNPs) are associated with obesity risk or metabolic abnormalities in a community population basis is unknown. METHODS: Samples were obtained from the Australian Crossroads study bio-bank. SNPs located in the coding region and 3'untranslated regions of RUNX1T1 with minor allele frequency ≥0.05 were analysed using Taqman genotyping assays. RESULTS: Eight candidate SNPs were genotyped successfully in 1440 participants. Of these SNPs only rs34269950 located in the 'RRACH' motif, the most common N6-methyladenosine (m6A) methylation modification site (recognized by FTO), was significantly associated with obesity risk and metabolic abnormalities. Specifically, compared to AA genotype, rs34269950 del/del genotype was associated with a 1.47 [95% confidence interval (CI): 1.01-2.14, P = 0.042] fold higher rate of obesity risk. Additionally, the del/del genotype was associated with a 60% increased risk of metabolic syndrome (MetS) [odds ratio (OR) = 1.60, 95% CI: 1.10-2.32, P = 0.015], in comparison to the AA genotype. Finally, rs34269950 del/del increased the risk of a larger waist circumference (OR = 1.65, 95% CI: 1.15-2.36, P = 0.007), but not other components of MetS. CONCLUSION: Our study demonstrates that RUNX1T1 rs34269950, located in a potential FTO recognition motif, is significantly associated with waist circumference. This provides novel evidence to suggest SNPs located in RRACH motif may be involved in RNA m6A modification and mechanistic pathways that influence abdominal obesity.


Assuntos
Síndrome Metabólica , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Austrália , Predisposição Genética para Doença , Humanos , Síndrome Metabólica/genética , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Proteína 1 Parceira de Translocação de RUNX1
10.
Diabet Med ; 38(1): e14380, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32750184

RESUMO

AIM: To evaluate the diagnostic and prognostic performance of alternative diagnostic strategies to oral glucose tolerance tests, including random plasma glucose, fasting plasma glucose and HbA1c , during the COVID-19 pandemic. METHODS: Retrospective service data (Cambridge, UK; 17 736 consecutive singleton pregnancies, 2004-2008; 826 consecutive gestational diabetes pregnancies, 2014-2019) and 361 women with ≥1 gestational diabetes risk factor (OPHELIA prospective observational study, UK) were included. Pregnancy outcomes included gestational diabetes (National Institute of Health and Clinical Excellence or International Association of Diabetes and Pregnancy Study Groups criteria), diabetes in pregnancy (WHO criteria), Caesarean section, large-for-gestational age infant, neonatal hypoglycaemia and neonatal intensive care unit admission. Receiver-operating characteristic curves and unadjusted logistic regression were used to compare random plasma glucose, fasting plasma glucose and HbA1c performance. RESULTS: Gestational diabetes diagnosis was significantly associated with random plasma glucose at 12 weeks [area under the receiver-operating characteristic curve for both criteria 0.81 (95% CI 0.79-0.83)], fasting plasma glucose [National Institute of Health and Clinical Excellence: area under the receiver-operating characteristic curve 0.75 (95% CI 0.65-0.85); International Association of Diabetes and Pregnancy Study Groups: area under the receiver-operating characteristic curve 0.92 (95% CI 0.85-0.98)] and HbA1c at 28 weeks' gestation [National Institute of Health and Clinical Excellence: 0.83 (95% CI 0.75-0.90); International Association of Diabetes and Pregnancy Study Groups: 0.84 (95% CI 0.77-0.91)]. Each measure predicts some, but not all, pregnancy outcomes studied. At 12 weeks, ~5% of women would be identified using random plasma glucose ≥8.5 mmol/l (sensitivity 42%; specificity 96%) and at 28 weeks using HbA1c ≥39 mmol/mol (sensitivity 26%; specificity 96%) or fasting plasma glucose ≥5.2-5.4 mmol/l (sensitivity 18-41%; specificity 97-98%). CONCLUSIONS: Random plasma glucose at 12 weeks, and fasting plasma glucose or HbA1c at 28 weeks identify women with hyperglycaemia at risk of suboptimal pregnancy outcomes. These opportunistic laboratory tests perform adequately for risk stratification when oral glucose tolerance testing is not available.


Assuntos
COVID-19/prevenção & controle , Diabetes Gestacional/diagnóstico , Hiperglicemia/diagnóstico , Programas de Rastreamento/métodos , SARS-CoV-2 , Adulto , Glicemia/análise , COVID-19/epidemiologia , Comorbidade , Diabetes Gestacional/epidemiologia , Jejum/sangue , Feminino , Idade Gestacional , Teste de Tolerância a Glucose , Hemoglobinas Glicadas/análise , Humanos , Pandemias , Gravidez , Resultado da Gravidez/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Sensibilidade e Especificidade , Reino Unido/epidemiologia
11.
Diabet Med ; 38(2): e14413, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32991758

RESUMO

AIMS: To describe the metabolic phenotypes of early gestational diabetes mellitus and their association with adverse pregnancy outcomes. METHODS: We performed a post hoc analysis using data from the Vitamin D And Lifestyle Intervention for gestational diabetes prevention (DALI) trial conducted across nine European countries (2012-2014). In women with a BMI ≥29 kg/m2 , insulin resistance and secretion were estimated from the oral glucose tolerance test values performed before 20 weeks, using homeostatic model assessment of insulin resistance and Stumvoll first-phase indices, respectively. Women with early gestational diabetes, defined by the International Association of Diabetes and Pregnancy Study Groups criteria, were classified into three groups: GDM-R (above-median insulin resistance alone), GDM-S (below-median insulin secretion alone), and GDM-B (combination of both) and the few remaining women were excluded. RESULTS: Compared with women in the normal glucose tolerance group (n = 651), women in the GDM-R group (n = 143) had higher fasting and post-load glucose values and insulin levels, with a greater risk of having large-for-gestational age babies [adjusted odds ratio 3.30 (95% CI 1.50-7.50)] and caesarean section [adjusted odds ratio 2.30 (95% CI 1.20-4.40)]. Women in the GDM-S (n = 37) and GDM-B (n = 56) groups had comparable pregnancy outcomes with those in the normal glucose tolerance group. CONCLUSIONS: In overweight and obese women with early gestational diabetes, higher degree of insulin resistance alone was more likely to be associated with adverse pregnancy outcomes than lower insulin secretion alone or a combination of both.


Assuntos
Glicemia/metabolismo , Cesárea/estatística & dados numéricos , Diabetes Gestacional/epidemiologia , Diabetes Gestacional/metabolismo , Macrossomia Fetal/epidemiologia , Idade Gestacional , Insulina/metabolismo , Obesidade Materna/epidemiologia , Adulto , Feminino , Teste de Tolerância a Glucose , Humanos , Resistência à Insulina , Secreção de Insulina , Fenótipo , Gravidez
13.
IMA Fungus ; 11: 20, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33062585

RESUMO

We formed the Collection of Zoosporic Eufungi at the University of Michigan (CZEUM) in 2018 as a cryopreserved fungal collection consolidating the University of Maine Culture Collection (UMCC, or JEL), the University of Alabama Chytrid Culture Collection (UACCC), and additional zoosporic eufungal accessions. The CZEUM is established as a community resource containing 1045 cryopreserved cultures of Chytridiomycota, Monoblepharidomycota, and Blastocladiomycota, with 52 cultures being ex-type strains. We molecularly characterized 431 cultures by amplifying the majority of the rDNA operon in a single reaction, yielding an average fragment length of 4739 bp. We sequenced multiplexed samples with an Oxford Nanopore Technology MinION device and software, and demonstrate the method is accurate by producing sequences identical to published Sanger sequences. With these data, we generated a phylogeny of 882 zoosporic eufungi strains to produce the most comprehensive phylogeny of these taxa to date. The CZEUM is thus largely characterized by molecular data, which can guide instructors and researchers on future studies of these organisms. Cultures from the CZEUM can be purchased through an online portal.

14.
J Neuroeng Rehabil ; 17(1): 127, 2020 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-32919473

RESUMO

BACKGROUND: Individuals with acquired brain injuries (ABI) are in need of neurorehabilitation and neurorepair. Virtual anatomical interactivity (VAI) presents a digital game-like format in which ABI survivors with upper limb paresis use an unaffected limb to control a standard input device and a commonplace computer mouse to control virtual limb movements and tasks in a virtual world. METHODS: In a prospective cohort study, 35 ambulatory survivors of ABI (25/71% stroke, 10/29% traumatic brain injury) were enrolled. The subjects were divided into three groups: group A received VAI therapy only, group B received VAI and physical/occupational therapy (P/OT), and group C received P/OT only. Motor skills were evaluated by muscle strength (hand key pinch strength, grasp, and three-jaw chuck pinch) and active range of motion (AROM) of the shoulder, elbow, and wrist. Changes were analyzed by ANOVA, ANCOVA, and one-tailed Pearson correlation analysis. MRI data was acquired for group A, and volumetric changes in grey matter were analyzed using voxel-based morphometry (VBM) and correlated with quantified motor skills. RESULTS: AROM of the shoulder, elbow, and wrist improved in all three groups. VBM revealed grey matter increases in five brain areas: the tail of the hippocampus, the left caudate, the rostral cingulate zone, the depth of the central sulcus, and the visual cortex. A positive correlation between the grey matter volumes in three cortical regions (motor and premotor and supplementary motor areas) and motor test results (power and AROM) was detected. CONCLUSIONS: Our findings suggest that the VAI rehabilitation program significantly improved motor function and skills in the affected upper extremities of subjects with acquired brain injuries. Significant increases in grey matter volume in the motor and premotor regions of affected hemisphere and correlations of motor skills and volume in nonaffected brain regions were present, suggesting marked changes in structural brain plasticity. TRIAL REGISTRATION: The trial "Limitations of motor brain activity - use of virtual reality for simulation of therapeutic interventions" has been registered under reference number ISRCTN11757651 .


Assuntos
Lesões Encefálicas/reabilitação , Recuperação de Função Fisiológica , Reabilitação do Acidente Vascular Cerebral/métodos , Realidade Virtual , Adulto , Idoso , Encéfalo/patologia , Lesões Encefálicas/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Terapia Ocupacional , Estudos Prospectivos , Jogos de Vídeo
15.
mBio ; 11(5)2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32900807

RESUMO

Mycoviruses are widespread and purportedly common throughout the fungal kingdom, although most are known from hosts in the two most recently diverged phyla, Ascomycota and Basidiomycota, together called Dikarya. To augment our knowledge of mycovirus prevalence and diversity in underexplored fungi, we conducted a large-scale survey of fungi in the earlier-diverging lineages, using both culture-based and transcriptome-mining approaches to search for RNA viruses. In total, 21.6% of 333 isolates were positive for RNA mycoviruses. This is a greater proportion than expected based on previous taxonomically broad mycovirus surveys and is suggestive of a strong phylogenetic component to mycoviral infection. Our newly found viral sequences are diverse, composed of double-stranded RNA, positive-sense single-stranded RNA (ssRNA), and negative-sense ssRNA genomes and include novel lineages lacking representation in the public databases. These identified viruses could be classified into 2 orders, 5 families, and 5 genera; however, half of the viruses remain taxonomically unassigned. Further, we identified a lineage of virus-like sequences in the genomes of members of Phycomycetaceae and Mortierellales that appear to be novel genes derived from integration of a viral RNA-dependent RNA polymerase gene. The two screening methods largely agreed in their detection of viruses; thus, we suggest that the culture-based assay is a cost-effective means to quickly assess whether a laboratory culture is virally infected. This study used culture collections and publicly available transcriptomes to demonstrate that mycoviruses are abundant in laboratory cultures of early-diverging fungal lineages. The function and diversity of mycoviruses found here will help guide future studies into mycovirus origins and ecological functions.IMPORTANCE Viruses are key drivers of evolution and ecosystem function and are increasingly recognized as symbionts of fungi. Fungi in early-diverging lineages are widespread, ecologically important, and comprise the majority of the phylogenetic diversity of the kingdom. Viruses infecting early-diverging lineages of fungi have been almost entirely unstudied. In this study, we screened fungi for viruses by two alternative approaches: a classic culture-based method and by transcriptome-mining. The results of our large-scale survey demonstrate that early-diverging lineages have higher infection rates than have been previously reported in other fungal taxa and that laboratory strains worldwide are host to infections, the implications of which are unknown. The function and diversity of mycoviruses found in these basal fungal lineages will help guide future studies into mycovirus origins and their evolutionary ramifications and ecological impacts.


Assuntos
Micovírus/classificação , Micovírus/genética , Fungos/virologia , Genoma Viral , Filogenia , Evolução Molecular , Micovírus/isolamento & purificação , Fungos/classificação , Fungos/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , RNA Viral/genética , Transcriptoma
16.
Environ Monit Assess ; 192(6): 404, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32472215

RESUMO

The St. Lawrence River, at Cornwall Ontario, has accumulated sediment contaminants, mainly mercury (Hg) and polychlorinated biphenyls (PCBs), from industrial point sources over many years. Although those sources are past, the river at Cornwall remains an Area of Concern (AOC). Because of remediation and other changes in the AOC, improved knowledge of contaminants in wild-fish and their putative links to health effects could help decision makers to better assess the AOC's state. Thus, we compared tissue concentrations of Hg, PCBs, morphometric measures of health, and biomarkers of exposure, metabolic-, and reproductive health in native brown bullhead (Ameiurus nebulosus) from the AOC to those of upstream reference fish. Linear discriminant analysis separated the adult fish of both sexes among upstream and downstream sites without misclassification. Burdens of total-Hg (all sites) and PCB toxic equivalents (downstream sites) exceeded the guidance for the protection of wildlife consumers. There were subtle effects of site on physiological variables, particularly in female fish. Total-Hg in tissue correlated negatively to plasma testosterone and 17ß-estradiol in female fish at Cornwall: moreover, concentrations of both hormones were lower within the AOC compared to reference site fish. A similar effect on vitellogenin, which was uncorrelated to E2/T at the downstream sites, indicated the potential for reproductive effects. Downstream fish also had altered thyroidal status (T3, TSH, and ratio of thyroid epithelial cell area to colloid area). Despite spatial and temporal variability of the endocrine-related responses, these subtle effects on fish health within the AOC warrant further study.


Assuntos
Ictaluridae , Mercúrio , Bifenilos Policlorados , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Feminino , Masculino , Ontário
17.
Mycologia ; 112(3): 606-615, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32271133

RESUMO

Aquaculture companies grow the green alga Haematococcus pluvialis (Chlorophyta) to extract the carotenoid astaxanthin to sell, which is used as human and animal dietary supplements. We were requested to identify an unknown pathogen of H. pluvialis from an alga growing facility in the southwestern United States. To identify this zoosporic fungus and determine its phylogenetic placement among other chytrids, we isolated it into pure culture, photographed its morphology and zoospore ultrastructure, and sequenced and analyzed portions of nuc rDNA 18S and 28S genes. The organism belongs in the Chytridiomycota, but a comparison of rDNA with available representatives of the phylum did not convincingly place it in any described order. The unique zoospore ultrastructure supports its indeterminate ordinal position, and the morphology, as determined by light microscopy, did not match any described species. Consequently, we have placed this chytrid in the new genus, Quaeritorhiza, and described it as the new species Q. haematococci in the family Quaeritorhizaceae but otherwise incertae sedis in the Chytridiomycetes. This new taxon is important because it increases the known diversity of Chytridiomycota and the organism has the ability to disrupt agricultural production of an algal monoculture.


Assuntos
Clorófitas/parasitologia , Quitridiomicetos/classificação , Quitridiomicetos/citologia , DNA Fúngico/genética , Filogenia , Aquicultura , Sudoeste dos Estados Unidos , Xantofilas
18.
Vision Res ; 170: 53-59, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32259647

RESUMO

A masked randomised control design compared the effectiveness of precision ophthalmic tints in improving the recognition of emotion in Autism Spectrum Disorders (ASD). Fourteen children aged 10-14 with ASD and 14 control children matched on verbal and non-verbal IQ, wore spectacles with coloured lenses to complete two tasks that involved the observation of coloured video sequences in which social interactions were depicted. On one occasion (randomly first or second) the coloured lenses provided light of a colour that the child had one month previously selected as optimal for the clarity of text. On the other occasion the lenses differed in CIE UCS chromaticity by 0.077. Performance in the ASD group was superior in both social interaction tasks with the lenses that provided the optimal colour of light.


Assuntos
Transtorno do Espectro Autista , Reconhecimento Psicológico , Cognição Social , Transtorno do Espectro Autista/fisiopatologia , Estudos de Casos e Controles , Criança , Emoções , Óculos , Humanos , Leitura
19.
QJM ; 113(7): 469-473, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32073638

RESUMO

BACKGROUND: There is limited understanding on whether and how socioeconomic status (SES), particularly educational attainment and household income, impacts on telomere length in an Australian rural context. Additionally, it is unknown whether access to health services via the Australian public or private health system influences telomere length. AIM: This study investigates whether there is a relationship between telomere length and SES indicators (income, education) as well as health insurance status in a rural Australian population. METHODS: Samples were drawn from the Australian Rural Victoria cross-sectional Crossroads Study. Leucocyte telomere length (LTL) was measured using a multiplex quantitative polymerase chain reaction method. RESULTS: Among 1424 participants, we did not find a significant main effect association with LTL across education, income level and health insurance. An exploratory finding was sex may influence the relationship between educational attainment and LTL (P = 0.021). In males, but not females, higher education was associated with longer LTL by 0.033 [95% confidence interval (CI) 0.002-0.063, P = 0.035]; in those with low education attainment, male participants had shorter LTL by 0.058 (95% CI -0.086 to -0.029) than female participants (P < 0.0001). CONCLUSION: Being male and having lower education attainment was associated with shorter telomere length in our rural population. Evidence from our study supports the importance of education on LTL in males in rural Australia. Our studies also support previous findings that LTL in later life may not be closely associated with indicators of SES.


Assuntos
Caracteres Sexuais , Classe Social , Encurtamento do Telômero , Austrália , Estudos Transversais , Escolaridade , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , População Rural
20.
Diabet Med ; 37(12): 2050-2057, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32027045

RESUMO

AIM: To assess whether incidence of maternal and neonatal outcomes for women with or without gestational diabetes mellitus (GDM) have changed over time. METHODS: Population-based cohort study in Sweden including all singleton pregnancies over the period 1998-2012. GDM was diagnosed following Diabetic Pregnancy Study Group 1991 criteria. Poisson regression or negative binomial regression was used to model yearly relative change in numbers of cases and incidence of the outcomes with 95% confidence intervals (CI), and yearly absolute change in birthweight z-score. RESULTS: The study included 1 455 667 pregnancies. The number of pregnancies increased over time and the overall prevalence of GDM was 1%. For women with GDM there was a significantly decreasing trend in incidence per year for large for gestational age (LGA) (0.986, 95% CI 0.975 to 0.996), birthweight z-score (-0.012, 95% CI -0.017 to -0.007) and birth trauma (0.937, 95% CI 0.907 to 0.968). The trend for small for gestational age (SGA) among women with GDM increased by an odds ratio per year (1.016, 95% CI 1.002 to 1.029). No significant interaction tests for maternal characteristics were found. Trends in outcomes for women without diabetes were similar to those for women with GDM. CONCLUSIONS: This study shows that there were improvements in pregnancy outcomes for women with GDM between 1998 and 2012, although the incidence of SGA increased. Improvements followed similar trends in the background population. Inequalities in obstetric outcomes between women with GDM and those without have continued unchanged over 15 years, suggesting that new management strategies are required to reduce this gap.


Assuntos
Traumatismos do Nascimento/epidemiologia , Diabetes Gestacional/epidemiologia , Macrossomia Fetal/epidemiologia , Resultado da Gravidez/epidemiologia , Adulto , Estudos de Coortes , Feminino , Retardo do Crescimento Fetal/epidemiologia , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Razão de Chances , Mortalidade Perinatal/tendências , Gravidez , Nascimento Prematuro/epidemiologia , Prevalência , Suécia/epidemiologia , Adulto Jovem
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