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2021 ◽  
Vol 10 (1) ◽  
pp. 27
Author(s):  
Magdalena Ksiezarek ◽  
Ângela Novais ◽  
Luísa Peixe

Since the discovery of the urinary microbiome, including the identification of Escherichia coli in healthy hosts, its involvement in UTI development has been a subject of high interest. We explored the population diversity and antimicrobial resistance of E. coli (n = 22) in the urogenital microbiome of ten asymptomatic women (representing 50% of the sample tested). We evaluated their genomic relationship with extraintestinal pathogenic E. coli (ExPEC) strains from healthy and diseased hosts, including the ST131 lineage. E. coli prevalence was higher in vaginal samples than in urine samples, and occasionally different lineages were observed in the same individual. Furthermore, B2 was the most frequent phylogenetic group, with the most strains classified as ExPEC. Resistance to antibiotics of therapeutic relevance (e.g., amoxicillin-clavulanate conferred by blaTEM-30) was observed in ExPEC widespread lineages sequence types (ST) 127, ST131, and ST73 and ST95 clonal complexes. Phylogenomics of ST131 and other ExPEC lineages revealed close relatedness with strains from gastrointestinal tract and diseased host. These findings demonstrate that healthy urogenital microbiome is a source of potentially pathogenic and antibiotic resistant E. coli strains, including those causing UTI, e.g., ST131. Importantly, diverse E. coli lineages can be observed per individual and urogenital sample type which is relevant for future studies screening for this uropathogen.


2021 ◽  
Author(s):  
Shing Wan Choi ◽  
Timothy Shin Heng Mak ◽  
Clive J. Hoggart ◽  
Paul F. O'Reilly

Background: Polygenic risk score (PRS) analyses are now routinely applied in biomedical research, with great hope that they will aid in our understanding of disease aetiology and contribute to personalized medicine. The continued growth of multi-cohort genome-wide association studies (GWASs) and large-scale biobank projects has provided researchers with a wealth of GWAS summary statistics and individual-level data suitable for performing PRS analyses. However, as the size of these studies increase, the risk of inter-cohort sample overlap and close relatedness increases. Ideally sample overlap would be identified and removed directly, but this is typically not possible due to privacy laws or consent agreements. This sample overlap, whether known or not, is a major problem in PRS analyses because it can lead to inflation of type 1 error and, thus, erroneous conclusions in published work. Results: Here, for the first time, we report the scale of the sample overlap problem for PRS analyses by generating known sample overlap across sub-samples of the UK Biobank data, which we then use to produce GWAS and target data to mimic the effects of inter-cohort sample overlap. We demonstrate that inter-cohort overlap results in a significant and often substantial inflation in the observed PRS-trait association, coefficient of determination (R2) and false-positive rate. This inflation can be high even when the absolute number of overlapping individuals is small if this makes up a notable fraction of the target sample. We develop and introduce EraSOR (Erase Sample Overlap and Relatedness), a software for adjusting inflation in PRS prediction and association statistics in the presence of sample overlap or close relatedness between the GWAS and target samples. A key component of the EraSOR approach is inference of the degree of sample overlap from the intercept of a bivariate LD score regression applied to the GWAS and target data, making it powered in settings where both have sample sizes over 1,000 individuals. Through extensive benchmarking using UK Biobank and HapGen2 simulated genotype-phenotype data, we demonstrate that PRSs calculated using EraSOR-adjusted GWAS summary statistics are robust to inter-cohort overlap in a wide range of realistic scenarios and are even robust to high levels of residual genetic and environmental stratification. Conclusion: The results of all PRS analyses for which sample overlap cannot be definitively ruled out should be considered with caution given high type 1 error observed in the presence of even low overlap between base and target cohorts. Given the strong performance of EraSOR in eliminating inflation caused by sample overlap in PRS studies with large (>5k) target samples, we recommend that EraSOR be used in all future such PRS studies to mitigate the potential effects of inter-cohort overlap and close relatedness.


2021 ◽  
Author(s):  
Magdalena Ksiezarek ◽  
Angela Novais ◽  
Luisa Peixe

Since the discovery of the urinary microbiome, including identification of Escherichia coli in healthy host, its involvement in UTI development is a subject of high interest. We explored population diversity and antimicrobial resistance of E. coli from urogenital microbiome of asymptomatic and recurrent UTI (rUTI) women. We also evaluated the genomic relationship between extraintestinal pathogenic E. coli (ExPEC) strains from healthy and diseased host, particularly of the ST131 lineage. E. coli was highly prevalent in asymptomatic women (48%) with slightly higher prevalence in vaginal samples comparing to urine, and occasionally with multiclonal population in the same individual. B2 was the most frequent phylogenetic group, with most strains classified as ExPEC. We demonstrated that virulence associated genes profile does not allow to distinguish strains isolated from healthy and rUTI host. We identified E. coli widespread lineages e.g., sequence types (ST) 127, ST131 (asymptomatic cohort) and ST73, ST131 (rUTI), frequently resistant to at least one antibiotic. Phylogenomics of ST131 and other ExPEC lineages revealed close relatedness between healthy and diseased host. These findings demonstrate that healthy urogenital microbiome is a source of potentially pathogenic and antibiotic resistant E. coli strains, including globally spread E. coli lineages causing UTI including ST131.


2021 ◽  
Vol 01 (01) ◽  
pp. 17-25
Author(s):  
Makwin Makut ◽  
◽  
Murtala Zaharadeen Ibrahim

Background: Over the past years, the continuous use of herbicides has raised increasing concern mainly due to their massive pollution of the environment. To address this problem, the herbicide-degrading microorganism might be very promising. Method: In the present study, a total of twenty (20) soil samples were collected, bacteria and fungi were isolated from the soil and identified using standard microbiological and molecular studies. Results: The results revealed that a total of 2 bacterial (Enterobacter asburiae and Pseudomonas aeruginosa) and 2 fungi (Aspergillus flavus and Fusarium redolens) strains were isolated from the soil samples collected from herbicide contaminated soil in Keffi, Nasarawa State, Nigeria. The E. asburiae and P. aeruginosa had 75.0%, and 100% occurrence while the fungi isolates including the A. flavus and F. redolens had 75.0%, and 100% occurrence respectively. The 16S rDNA and ITS1F analysis confirmed the identity of the bacteria and fungi genus. Phylogenetic analysis suggested the bacteria strains were closely related to Pseudomonas aeruginosa strain CIFRI DTSB1 and Enterobacter sp revealed a close relatedness with Enterobacter asburiae RD-DAROS-04 strain, whereas, the fungi strain revealed a closely relatedness of Fusarium redolens strainTIST190421511. Conclusion: In conclusion, the microbial strains including Pseudomonas aeruginosa strain CIFRI DTSB1, Entrobacter asburiae RD-DAROS-04, and Fusarium redolens strainTIST190421511 were the major microbial habitant of pesticide-contaminated farmland in Keffi, and thus represent the herbicide degrading microorganism in this region. Further studies on the herbicide degrading properties of these microbial strains are underway.


2021 ◽  
Vol 9 (8) ◽  
pp. 1653
Author(s):  
Rhys Parry ◽  
Maddie E James ◽  
Sassan Asgari

Aedes aegypti, the yellow fever mosquito, and Aedes albopictus, the Asian tiger mosquito, are the most significant vectors of dengue, Zika, and Chikungunya viruses globally. Studies examining host factors that control arbovirus transmission demonstrate that insect-specific viruses (ISVs) can modulate mosquitoes’ susceptibility to arbovirus infection in both in vivo and in vitro co-infection models. While research is ongoing to implicate individual ISVs as proviral or antiviral factors, we have a limited understanding of the composition and diversity of the Aedes virome. To address this gap, we used a meta-analysis approach to uncover virome diversity by analysing ~3000 available RNA sequencing libraries representing a worldwide geographic range for both mosquitoes. We identified ten novel viruses and previously characterised viruses, including mononegaviruses, orthomyxoviruses, negeviruses, and a novel bi-segmented negev-like group. Phylogenetic analysis suggests close relatedness to mosquito viruses implying likely insect host range except for one arbovirus, the multi-segmented Jingmen tick virus (Flaviviridae) in an Italian colony of Ae. albopictus. Individual mosquito transcriptomes revealed remarkable inter-host variation of ISVs within individuals from the same colony and heterogeneity between different laboratory strains. Additionally, we identified striking virus diversity in Wolbachia infected Aedes cell lines. This study expands our understanding of the virome of these important vectors. It provides a resource for further assessing the ecology, evolution, and interaction of ISVs with their mosquito hosts and the arboviruses they transmit.


2021 ◽  
Author(s):  
Charles Bachy ◽  
Charmaine C. M. Yung ◽  
David M. Needham ◽  
Maria Consuelo Gazitúa ◽  
Simon Roux ◽  
...  

AbstractThe marine picoeukaryote Bathycoccus prasinos has been considered a cosmopolitan alga, although recent studies indicate two ecotypes exist, Clade BI (B. prasinos) and Clade BII. Viruses that infect Bathycoccus Clade BI are known (BpVs), but not that infect BII. We isolated three dsDNA prasinoviruses from the Sargasso Sea against Clade BII isolate RCC716. The BII-Vs do not infect BI, and two (BII-V2 and BII-V3) have larger genomes (~210 kb) than BI-Viruses and BII-V1. BII-Vs share ~90% of their proteins, and between 65% to 83% of their proteins with sequenced BpVs. Phylogenomic reconstructions and PolB analyses establish close-relatedness of BII-V2 and BII-V3, yet BII-V2 has 10-fold higher infectivity and induces greater mortality on host isolate RCC716. BII-V1 is more distant, has a shorter latent period, and infects both available BII isolates, RCC716 and RCC715, while BII-V2 and BII-V3 do not exhibit productive infection of the latter in our experiments. Global metagenome analyses show Clade BI and BII algal relative abundances correlate positively with their respective viruses. The distributions delineate BI/BpVs as occupying lower temperature mesotrophic and coastal systems, whereas BII/BII-Vs occupy warmer temperature, higher salinity ecosystems. Accordingly, with molecular diagnostic support, we name Clade BII Bathycoccus calidus sp. nov. and propose that molecular diversity within this new species likely connects to the differentiated host-virus dynamics observed in our time course experiments. Overall, the tightly linked biogeography of Bathycoccus host and virus clades observed herein supports species-level host specificity, with strain-level variations in infection parameters.


2021 ◽  
Author(s):  
Felicia Chan ◽  
Ricardo Ataide ◽  
Jack S Richards ◽  
Charles Akugbey Narh

SARS-CoV-2, the coronavirus causing COVID-19, has infected and killed several millions of people worldwide. Since the first COVID-19 outbreak in December 2019, SARS-CoV-2 has evolved with a few genetic variants associated with higher infectivity. We aimed to identify polymorphic loci in SARS-CoV-2 that can be used to define and monitor the viral epidemiology and population genetics in different geographical regions. Between December 2019 and September 2020, we sampled 5,959 SARS-CoV-2 genomes. More than 80% of the genomes sampled in Africa, Asia, Europe, North America, Oceania and South America were reportedly isolated from clinical infections in older patients, ≥ 20 years. We used the first indexed genome (NC_045512.2) as a reference and constructed multilocus genotypes (MLGs) for each sampled genome based on amino acids detected at 74 polymorphic loci located in ORF1ab, ORF3a, ORF8, matrix (M), nucleocapsid (N) and spike (S) genes. Eight of the 74 loci were informative in estimating the risk of carrying infections with mutant alleles among different age groups, gender and geographical regions. Four mutant alleles - ORF1ab L4715, S G614, and N K203 and R204 reached 90% prevalence globally, coinciding with peaks in transmission but not COVID-19 severity, from March to August 2020. During this period, the MLG genetic diversity was moderate in Asia, Oceania and North America; in contrast to Africa, Europe and South America, where lower genetic diversity and absence of linkage disequilibrium indicated clonal SARS-CoV-2 transmission. Despite close relatedness to Asian MLGs, MLGs in the global population were genetically differentiated by geographic region, suggesting structure in SARS-CoV-2 populations. Our findings demonstrate the utility of the 74 loci as a genetic tool to study and monitor SARS-CoV-2 transmission dynamics and evolution, which can inform future control interventions.


2021 ◽  
Author(s):  
Lluis Oviedo ◽  
Jose Maria Torralba Muñoz ◽  
Jose Luis Ripoll

Some uneasy and dissatisfaction with current research on perceptions of supernatural in certain stages of children and youth development has motivated a search for an alternative approach that could be built on new empirical data and a method that could help to better assess how pre- and adolescents relate to extraordinary and supernatural phenomena. An exploratory survey has been designed on an ad hoc instrument, fitted for that age span and the research goals. The outcomes point to the persistence of these perceptions and interests in that age, their close relatedness with indicators of religiosity, and their slowly vanishing when growing up. More research is needed to better ascertain the role this factor still plays in religious and spiritual development despite the very secular context in which often those beliefs are held.


2021 ◽  
Author(s):  
Lluis Oviedo ◽  
Josefa Torralba ◽  
Jose Luis Ripoll

Some uneasy and dissatisfaction with the current research on perceptions of supernatural in certain stages of children and youth development has motivated a search for an alternative approach that could be built on new empirical data and a method that could help to better assess how pre- and adolescents relate with extraordinary and supernatural phenomena. An exploratory survey has been designed on an ad hoc instrument fitted for that age span and the research goals. The outcomes point to the persistence of these perceptions and interests in that age, their close relatedness with indicators of religiosity, and their slowly vanishing when growing up. More research is needed to better ascertain the role this factor still plays in religious and spiritual development despite the very secular context in which often those beliefs are held.


2021 ◽  
Vol 22 (4) ◽  
pp. 1865
Author(s):  
Maikel B. F. Steentjes ◽  
Sebastian Tonn ◽  
Hilde Coolman ◽  
Sander Langebeeke ◽  
Olga E. Scholten ◽  
...  

Botrytis squamosa, Botrytis aclada, and Sclerotium cepivorum are three fungal species of the family Sclerotiniaceae that are pathogenic on onion. Despite their close relatedness, these fungi cause very distinct diseases, respectively called leaf blight, neck rot, and white rot, which pose serious threats to onion cultivation. The infection biology of neck rot and white rot in particular is poorly understood. In this study, we used GFP-expressing transformants of all three fungi to visualize the early phases of infection. B. squamosa entered onion leaves by growing either through stomata or into anticlinal walls of onion epidermal cells. B. aclada, known to cause post-harvest rot and spoilage of onion bulbs, did not penetrate the leaf surface but instead formed superficial colonies which produced new conidia. S. cepivorum entered onion roots via infection cushions and appressorium-like structures. In the non-host tomato, S. cepivorum also produced appressorium-like structures and infection cushions, but upon prolonged contact with the non-host the infection structures died. With this study, we have gained understanding in the infection biology and strategy of each of these onion pathogens. Moreover, by comparing the infection mechanisms we were able to increase insight into how these closely related fungi can cause such different diseases.


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