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1.
Microbiol Spectr ; 12(4): e0398023, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38445873

ABSTRACT

Modern taxonomic classification is often based on phylogenetic analyses of a few molecular markers, although single-gene studies are still common. Here, we leverage genome-scale molecular phylogenetics (phylogenomics) of species and populations to reconstruct evolutionary relationships in a dense data set of 710 fungal genomes from the biomedically and technologically important genus Aspergillus. To do so, we generated a novel set of 1,362 high-quality molecular markers specific for Aspergillus and provided profile Hidden Markov Models for each, facilitating their use by others. Examining the resulting phylogeny helped resolve ongoing taxonomic controversies, identified new ones, and revealed extensive strain misidentification (7.59% of strains were previously misidentified), underscoring the importance of population-level sampling in species classification. These findings were corroborated using the current standard, taxonomically informative loci. These findings suggest that phylogenomics of species and populations can facilitate accurate taxonomic classifications and reconstructions of the Tree of Life.IMPORTANCEIdentification of fungal species relies on the use of molecular markers. Advances in genomic technologies have made it possible to sequence the genome of any fungal strain, making it possible to use genomic data for the accurate assignment of strains to fungal species (and for the discovery of new ones). We examined the usefulness and current limitations of genomic data using a large data set of 710 publicly available genomes from multiple strains and species of the biomedically, agriculturally, and industrially important genus Aspergillus. Our evolutionary genomic analyses revealed that nearly 8% of publicly available Aspergillus genomes are misidentified. Our work highlights the usefulness of genomic data for fungal systematic biology and suggests that systematic genome sequencing of multiple strains, including reference strains (e.g., type strains), of fungal species will be required to reduce misidentification errors in public databases.


Subject(s)
Aspergillus , Fungi , Phylogeny , Fungi/genetics , Aspergillus/genetics , Biological Evolution , Genomics , Genome, Fungal
2.
Front Microbiol ; 15: 1348063, 2024.
Article in English | MEDLINE | ID: mdl-38476938

ABSTRACT

Introduction: This study is the final part of a two-part series that delves into the molecular mechanisms driving adaptive laboratory evolution (ALE) of Salmonella enterica in acid stress. The phenotypic and transcriptomic alterations in the acid-evolved lineages (EL) of Salmonella enterica serovar Enteritidis after 70 days of acid stress exposure were analyzed. Materials and methods: The stability of phenotypic changes observed after 70 days in acetic acid was explored after stress removal using a newly developed evolutionary lineage EL5. Additionally, the impact of short-term acid stress on the previously adapted lineage EL4 was also examined. Results: The results indicate that the elevated antibiotic minimum inhibitory concentration (MIC) observed after exposure to acetic acid for 70 days was lost when acid stress was removed. This phenomenon was observed against human antibiotics such as meropenem, ciprofloxacin, gentamicin, and streptomycin. The MIC of meropenem in EL4 on day 70 was 0.094 mM, which dropped to 0.032 mM when removed from acetic acid stress after day 70. However, after stress reintroduction, the MIC swiftly elevated, and within 4 days, it returned to 0.094 mM. After 20 more days of adaptation in acetic acid, the meropenem MIC increased to 0.125 mM. The other human antibiotics that were tested exhibited a similar trend. The MIC of acetic acid in EL4 on day 70 was observed to be 35 mM, which remained constant even after the removal of acetic acid stress. Readaptation of EL4 in acetic acid for 20 more days caused the acetic acid MIC to increase to 37 mM. Bacterial whole genome sequencing of EL5 revealed base substitutions in several genes involved in pathogenesis, such as the phoQ and wzc genes. Transcriptomic analysis of EL5 revealed upregulation of virulence, drug resistance, toxin-antitoxin, and iron metabolism genes. Unstable Salmonella small colony variants (SSCV) of S. Enteritidis were also observed in EL5 as compared to the wild-type unevolved S. Enteritidis. Discussion: This study presents a comprehensive understanding of the evolution of the phenotypic, genomic, and transcriptomic changes in S. Enteritidis due to prolonged acid exposure through ALE.

3.
BMC Infect Dis ; 24(1): 252, 2024 Feb 23.
Article in English | MEDLINE | ID: mdl-38395793

ABSTRACT

BACKGROUND: Tuberculosis in the UK is more prevalent in people with social risk factors- e.g. previous incarceration, homelessness - and in migrants from TB endemic countries. The management of TB infection is part of TB elimination strategies, but is challenging to provide to socially excluded groups and the evidence base for effective interventions is small. METHODS: We evaluated a TB infection screening and treatment programme provided by a peer-led service (Find&Treat) working in inclusion health settings (e.g. homeless hostels) in London. IGRA (interferon-gamma release assay) testing and TB infection treatment were offered to eligible adults using a community-based model. The primary outcome was successful progression through the cascade of care. We also evaluated socio-demographic characteristics associated with a positive IGRA. RESULTS: 42/312 (13.5%) participants had a positive IGRA and no one had evidence of active TB. 35/42 completed a medical evaluation; 22 started treatment, and 17 completed treatment. Having a positive IGRA was associated with previous incarceration and being born outside of the UK. DISCUSSION: Provision of TB infection diagnosis and management to this socially excluded population has several challenges including maintaining people in care and drug-drug interactions. Peer-support workers provided this service safely and effectively with appropriate support. Further work to generate data to inform risks and benefits of treatment for TB infection in this group is needed to facilitate joint decision making.


Subject(s)
Latent Tuberculosis , Tuberculosis , Adult , Humans , Tuberculin Test , London/epidemiology , Tuberculosis/diagnosis , Tuberculosis/drug therapy , Tuberculosis/epidemiology , Latent Tuberculosis/diagnosis , Latent Tuberculosis/drug therapy , Latent Tuberculosis/epidemiology , Interferon-gamma Release Tests
4.
J Neuropathol Exp Neurol ; 82(12): 976-986, 2023 11 20.
Article in English | MEDLINE | ID: mdl-37944065

ABSTRACT

High-throughput digital pathology offers considerable advantages over traditional semiquantitative and manual methods of counting pathology. We used brain tissue from 5 clinical-pathologic cohort studies of aging; the Religious Orders Study, the Rush Memory and Aging Project, the Minority Aging Research Study, the African American Clinical Core, and the Latino Core to (1) develop a workflow management system for digital pathology processes, (2) optimize digital algorithms to quantify Alzheimer disease (AD) pathology, and (3) harmonize data statistically. Data from digital algorithms for the quantification of ß-amyloid (Aß, n = 413) whole slide images and tau-tangles (n = 639) were highly correlated with manual pathology data (r = 0.83 to 0.94). Measures were robust and reproducible across different magnifications and repeated scans. Digital measures for Aß and tau-tangles across multiple brain regions reproduced established patterns of correlations, even when samples were stratified by clinical diagnosis. Finally, we harmonized newly generated digital measures with historical measures across multiple large autopsy-based studies. We describe a multidisciplinary approach to develop a digital pathology pipeline that reproducibly identifies AD neuropathologies, Aß load, and tau-tangles. Digital pathology is a powerful tool that can overcome critical challenges associated with traditional microscopy methods.


Subject(s)
Alzheimer Disease , Humans , Alzheimer Disease/diagnostic imaging , Autopsy , Amyloid beta-Peptides , Neuropathology , Aging
5.
Front Microbiol ; 14: 1285421, 2023.
Article in English | MEDLINE | ID: mdl-38033570

ABSTRACT

Introduction: Adaptive laboratory evolution (ALE) studies play a crucial role in understanding the adaptation and evolution of different bacterial species. In this study, we have investigated the adaptation and evolution of Salmonella enterica serovar Enteritidis to acetic acid using ALE. Materials and methods: Acetic acid concentrations below the minimum inhibitory concentration (sub-MIC) were used. Four evolutionary lineages (EL), namely, EL1, EL2, EL3, and EL4, of S. Enteritidis were developed, each demonstrating varying levels of resistance to acetic acid. Results: The acetic acid MIC of EL1 remained constant at 27 mM throughout 70 days, while the MIC of EL2, EL3, and EL4 increased throughout the 70 days. EL4 was adapted to the highest concentration of acetic acid (30 mM) and demonstrated the highest increase in its MIC against acetic acid throughout the study, reaching an MIC of 35 mM on day 70. The growth rates of the evolved lineages increased over time and were dependent on the concentration of acetic acid used during the evolutionary process. EL4 had the greatest increase in growth rate, reaching 0.33 (h-1) after 70 days in the presence of 30 mM acetic acid as compared to EL1, which had a growth rate of 0.2 (h-1) after 70 days with no exposure to acetic acid. Long-term exposure to acetic acid led to an increased MIC of human antibiotics such as ciprofloxacin and meropenem against the S. enterica evolutionary lineages. The MIC of ciprofloxacin for EL1 stayed constant at 0.016 throughout the 70 days while that of EL4 increased to 0.047. Bacterial whole genome sequencing revealed single-nucleotide polymorphisms in the ELs in various genes known to be involved in S. enterica virulence, pathogenesis, and stress response including phoP, phoQ, and fhuA. We also observed genome deletions in some of the ELs as compared to the wild-type S. Enteritidis which may have contributed to the bacterial acid adaptation. Discussion: This study highlights the potential for bacterial adaptation and evolution under environmental stress and underscores the importance of understanding the development of cross resistance to antibiotics in S. enterica populations. This study serves to enhance our understanding of the pathogenicity and survival strategies of S. enterica under acetic acid stress.

6.
Cureus ; 15(6): e39831, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37397683

ABSTRACT

Introduction While pickleball and paddleball are rapidly growing as popular sports in the United States, research on the incidence of hand and upper extremity injuries and treatments in outpatient clinics are lacking. This study evaluates the incidence rates and treatment options, both surgically and nonsurgically, for patients presenting with pickleball/paddleball-related injuries. Methods A retrospective database search of our multispecialty, multilocation electronic medical record (EMR) system from 2015 to 2022 identified 204 patients with outpatient pickleball- and paddleball-related injuries. The data from these patients' charts were reviewed for injury incidences, treatment trends, and demographics. Results  The majority of patients suffered wrist fractures due to a fall/dive and were treated nonsurgically. The most common surgical treatment, when required, was open reduction and internal fixation of the distal radius. We found that pickleball and paddleball players who sustained wrist fractures required surgery at a higher rate than the general population if above the age of 65. Conclusion As pickleball and paddleball continue to gain popularity, hand surgeons should be aware of the types of injuries that can occur and, when possible, counsel patients accordingly to try to prevent them. Additionally, hand surgeons should recognize the common treatments and outcomes that arise from pickleball/paddleball-related injuries.

7.
Proc Natl Acad Sci U S A ; 120(10): e2214076120, 2023 03 07.
Article in English | MEDLINE | ID: mdl-36848567

ABSTRACT

Lentinula is a broadly distributed group of fungi that contains the cultivated shiitake mushroom, L. edodes. We sequenced 24 genomes representing eight described species and several unnamed lineages of Lentinula from 15 countries on four continents. Lentinula comprises four major clades that arose in the Oligocene, three in the Americas and one in Asia-Australasia. To expand sampling of shiitake mushrooms, we assembled 60 genomes of L. edodes from China that were previously published as raw Illumina reads and added them to our dataset. Lentinula edodes sensu lato (s. lat.) contains three lineages that may warrant recognition as species, one including a single isolate from Nepal that is the sister group to the rest of L. edodes s. lat., a second with 20 cultivars and 12 wild isolates from China, Japan, Korea, and the Russian Far East, and a third with 28 wild isolates from China, Thailand, and Vietnam. Two additional lineages in China have arisen by hybridization among the second and third groups. Genes encoding cysteine sulfoxide lyase (lecsl) and γ-glutamyl transpeptidase (leggt), which are implicated in biosynthesis of the organosulfur flavor compound lenthionine, have diversified in Lentinula. Paralogs of both genes that are unique to Lentinula (lecsl 3 and leggt 5b) are coordinately up-regulated in fruiting bodies of L. edodes. The pangenome of L. edodes s. lat. contains 20,308 groups of orthologous genes, but only 6,438 orthogroups (32%) are shared among all strains, whereas 3,444 orthogroups (17%) are found only in wild populations, which should be targeted for conservation.


Subject(s)
Lentinula , Phylogeny , Asia, Eastern , Thailand
8.
J Arthroplasty ; 38(4): 691-699, 2023 04.
Article in English | MEDLINE | ID: mdl-36272510

ABSTRACT

BACKGROUND: Cementless total knee arthroplasty (TKA) is the subject of renewed interest. Previous concerns about survivorship have been addressed and there is an appeal in terms of biological fixation and surgical efficiency. However, even surgeon advocates have concerns about the risk of marked subsidence when using this technology in older patients at risk for osteoporosis. METHODS: This was a retrospective analysis of 1,000 consecutive fully cementless mobile bearing TKAs performed at a single institution on women over 75 years of age who had postoperative and 1-year x-rays. The primary outcome was the incidence of subsidence. RESULTS: There were three asymptomatic cases with definite subsidence and change in alignment. In a fourth symptomatic case, the femoral component subsided into varus and the tibia into valgus, thus maintaining alignment which facilitated nonoperative treatment in a 92-year-old. Overall, at 1 year, there were two- liner revisions for infection without recurrence. Five patients had further surgery, of which three were washouts and two were for periprosthetic fractures sustained postoperatively within 1 year. Seven patients had further anesthesia, of which five were manipulations and two were nonrecurrent closed reductions for spinouts. CONCLUSION: Cementless TKA did not have a high risk of subsidence in this at-risk population. In the hands of experienced surgeons, these procedures can be used safely irrespective of bone quality.


Subject(s)
Arthroplasty, Replacement, Knee , Knee Prosthesis , Humans , Female , Aged , Aged, 80 and over , Arthroplasty, Replacement, Knee/adverse effects , Retrospective Studies , Knee Prosthesis/adverse effects , Tibia/surgery , Radiography , Reoperation , Treatment Outcome
9.
Microbiol Spectr ; 10(5): e0051922, 2022 10 26.
Article in English | MEDLINE | ID: mdl-36094204

ABSTRACT

Aspergillus fumigatus is a deadly opportunistic fungal pathogen responsible for ~100,000 annual deaths. Azoles are the first line antifungal agent used against A. fumigatus, but azole resistance has rapidly evolved making treatment challenging. Caspofungin is an important second-line therapy against invasive pulmonary aspergillosis, a severe A. fumigatus infection. Caspofungin functions by inhibiting ß-1,3-glucan synthesis, a primary and essential component of the fungal cell wall. A phenomenon termed the caspofungin paradoxical effect (CPE) has been observed in several fungal species where at higher concentrations of caspofungin, chitin replaces ß-1,3-glucan, morphology returns to normal, and growth rate increases. CPE appears to occur in vivo, and it is therefore clinically important to better understand the genetic contributors to CPE. We applied genomewide association (GWA) analysis and molecular genetics to identify and validate candidate genes involved in CPE. We quantified CPE across 67 clinical isolates and conducted three independent GWA analyses to identify genetic variants associated with CPE. We identified 48 single nucleotide polymorphisms (SNPs) associated with CPE. We used a CRISPR/Cas9 approach to generate gene deletion mutants for seven genes harboring candidate SNPs. Two null mutants, ΔAfu3g13230 and ΔAfu4g07080 (dscP), resulted in reduced basal growth rate and a loss of CPE. We further characterized the dscP phosphatase-null mutant and observed a significant reduction in conidia production and extremely high sensitivity to caspofungin at both low and high concentrations. Collectively, our work reveals the contribution of Afu3g13230 and dscP in CPE and sheds new light on the complex genetic interactions governing this phenotype. IMPORTANCE This is one of the first studies to apply genomewide association (GWA) analysis to identify genes involved in an Aspergillus fumigatus phenotype. A. fumigatus is an opportunistic fungal pathogen that causes hundreds of thousands of infections and ~100,000 deaths each year, and antifungal resistance has rapidly evolved in this species. A phenomenon called the caspofungin paradoxical effect (CPE) occurs in some isolates, where high concentrations of the drug lead to increased growth rate. There is clinical relevance in understanding the genetic basis of this phenotype, since caspofungin concentrations could lead to unintended adverse clinical outcomes in certain cases. Using GWA analysis, we identified several interesting candidate polymorphisms and genes and then generated gene deletion mutants to determine whether these genes were important for CPE. Two of these mutant strains (ΔAfu3g13230 and ΔAfu4g07080/ΔdscP) displayed a loss of the CPE. This study sheds light on the genes involved in clinically important phenotype CPE.


Subject(s)
Antifungal Agents , Aspergillus fumigatus , Caspofungin/pharmacology , Caspofungin/metabolism , Aspergillus fumigatus/genetics , Antifungal Agents/pharmacology , Echinocandins/pharmacology , Echinocandins/metabolism , Fungal Proteins/genetics , Fungal Proteins/metabolism , Azoles/metabolism , Azoles/pharmacology , Chitin , Genomics , Phosphoric Monoester Hydrolases/metabolism , Phosphoric Monoester Hydrolases/pharmacology
10.
mBio ; 13(4): e0151922, 2022 08 30.
Article in English | MEDLINE | ID: mdl-35766381

ABSTRACT

Aspergillus fumigatus is both an environmental saprobe and an opportunistic human fungal pathogen. Knowledge of genomic variation across A. fumigatus isolates is essential for understanding the evolution of pathogenicity, virulence, and resistance to antifungal drugs. Here, we investigated 206 A. fumigatus isolates (133 clinical and 73 environmental isolates), aiming to identify genes with variable presence across isolates and test whether this variation was related to the clinical or environmental origin of isolates. The PanOrtho genome of A. fumigatus consists of 13,085 ortholog groups, of which 7,773 (59.4%) are shared by all isolates (core groups) and 5,312 (40.6%) vary in their gene presence across isolates (accessory groups plus singletons). Despite differences in the distribution of orthologs across all isolates, no significant differences were observed among clinical versus environmental isolates when phylogeny was accounted for. Orthologs that differ in their distribution across isolates tend to occur at low frequency and/or be restricted to specific isolates; thus, the degree of genomic conservation between orthologs of A. fumigatus is high. These results suggest that differences in the distribution of orthologs within A. fumigatus cannot be associated with the clinical or environmental origin of isolates. IMPORTANCE Aspergillus fumigatus is a cosmopolitan species of fungus responsible for thousands of cases of invasive disease annually. Clinical and environmental isolates of A. fumigatus exhibit extensive phenotypic differences, including differences related to virulence and antifungal drug resistance. A comprehensive survey of the genomic diversity present in A. fumigatus and its relationship to the clinical or environmental origin of isolates can contribute to the prediction of the mechanisms of evolution and infection of the species. Our results suggest that there is no significant variation in ortholog distribution between clinical and environmental isolates when accounting for evolutionary history. The work supports the hypothesis that environmental and clinical isolates of A. fumigatus do not differ in their gene contents.


Subject(s)
Aspergillosis , Aspergillus fumigatus , Antifungal Agents/pharmacology , Aspergillosis/microbiology , Drug Resistance, Fungal/genetics , Fungal Proteins/genetics , Humans , Virulence/genetics
11.
HardwareX ; 11: e00289, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35509925

ABSTRACT

Crowd sourced data collection among the international community of amateur radio operators and shortwave listeners has great potential for addressing problems of under-sampling in the geospace system. Quantitative Doppler measurements of high frequency (HF) time standard stations, used in bottom side ionospheric sensing, have been accomplished using existing radio hardware belonging to volunteers in distributed campaigns. However, typical shortwave receivers cannot be put to ordinary use while these measurements are being taken, do not have standardized signal chains, and are generally too expensive to be purchased for the sole purpose of taking Doppler measurements. Here, we provide documentation for a low-cost intermediate frequency receiver, the Grape Version 1, which is designed specifically for measurements of North American time standard stations. Grape receivers can be easily constructed and deployed by amateur scientists in order to gain a deeper understanding of variations in radio propagation in their local environment. When compared over long periods and across distributed networks of stations, the resulting data yield insights on greater spatial and time scales. At the time of writing, several of these receivers have been deployed across the United States and are actively collecting data. These receivers form the first iteration of the Low-Cost Personal Space Weather Station network.

12.
Knee Surg Sports Traumatol Arthrosc ; 30(10): 3328-3333, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35212804

ABSTRACT

PURPOSE: The aim of this study was to identify if experience in arthroscopy confers ambidexterity to the operator and the role of baseline characteristics in arthroscopic simulator performance. METHODS: A prospective comparative study was carried out across four regional Orthopaedic training centres. Participants were divided into novice, intermediate or experienced groups based on arthroscopic experience. Baseline demographics including age, sex, handedness, and gaming history were also collected. Following familiarisation with the procedure, participants were asked to complete a simulated task requiring bimanual control consisting of visualisation with camera control and manipulation of highlighted objects using a grasping instrument. One attempt using camera control and grasping accuracy per hand was performed by each participant, with scores for each hand collected for analysis. Performance scores for camera alignment, camera path length, grasper path length and grasping efficiency were collected. Time taken to completion was also noted for each attempt. RESULTS: Fifty-six participants were recruited to the study. A significant difference in grasping efficiency between groups in the dominant hand was demonstrated (p = 0.013). Novices demonstrated laterality with superior performance in grasping efficiency in the dominant hand (p = 0.001). No significant difference was noted between dominant and non-dominant hand performance in the experienced group. CONCLUSION: Arthroscopic simulation-based training is a valuable learning tool for orthopaedic training. This study demonstrated that experienced orthopaedic surgeons have a greater degree of ambidexterity than intermediate or novice groups, hypothesised by authors to be conferred through conventional orthopaedic training. Dedicated bimanual control tasks to reduce laterality in trainees should be incorporated in simulated surgical curricula. LEVEL OF EVIDENCE: III.


Subject(s)
Orthopedics , Simulation Training , Arthroscopy/education , Clinical Competence , Computer Simulation , Humans , Orthopedics/education , Prospective Studies , Simulation Training/methods , Task Performance and Analysis
13.
Toxins (Basel) ; 14(2)2022 02 04.
Article in English | MEDLINE | ID: mdl-35202144

ABSTRACT

Sesame Sesamum indicum L. is a major oil-based seed crop that has been widely cultivated and consumed in Pakistan. Unfortunately, sesame is highly prone to Aspergillus fungal growth in the field, and under inappropriate storage conditions can become contaminated with aflatoxins, the most potent carcinogen found in nature. Here, we have isolated a high number of Aspergillus isolates from sesame seeds in fresh and stored conditions obtained from rainfed and irrigated zones of Punjab, Pakistan, and characterized them for aflatoxigenic potentials. Using morphological identification techniques, 260 isolates were grouped as potential Aspergillus section Flavi, with 126 and 134 originating from the rainfed and irrigated zones, respectively. Out of 260 in total, 188 isolates were confirmed to produce aflatoxins. There were no significant differences in potential aflatoxigenic isolates with respect to the rainfed and irrigated zones. However, the number of potential aflatoxigenic isolates was significantly higher (p < 0.05) in stored samples than that of those from fresh sesame seeds in the rainfed and irrigated zone. Whole genome sequencing and comparative analyses of 12 select isolates have revealed that one of the A. flavus isolates, which produced very low aflatoxins (AFP10), has an elevated missense variant rate, numerous high impact mutations, and a 600 base pair deletion in the norB gene. In summary, our study provides insights into aflatoxigenic potential and the associated genetic diversity of indigenous Aspergillus section Flavi isolates and potential management strategies for reducing aflatoxin contamination levels in a major crop consumed in Punjab, Pakistan.


Subject(s)
Aspergillus flavus/isolation & purification , Food Contamination/analysis , Seeds/microbiology , Sesamum/microbiology , Aspergillus flavus/genetics , Pakistan , Phylogeny , Whole Genome Sequencing
14.
Nat Commun ; 13(1): 136, 2022 01 10.
Article in English | MEDLINE | ID: mdl-35013263

ABSTRACT

Emerging research supports that triclosan (TCS), an antimicrobial agent found in thousands of consumer products, exacerbates colitis and colitis-associated colorectal tumorigenesis in animal models. While the intestinal toxicities of TCS require the presence of gut microbiota, the molecular mechanisms involved have not been defined. Here we show that intestinal commensal microbes mediate metabolic activation of TCS in the colon and drive its gut toxicology. Using a range of in vitro, ex vivo, and in vivo approaches, we identify specific microbial ß-glucuronidase (GUS) enzymes involved and pinpoint molecular motifs required to metabolically activate TCS in the gut. Finally, we show that targeted inhibition of bacterial GUS enzymes abolishes the colitis-promoting effects of TCS, supporting an essential role of specific microbial proteins in TCS toxicity. Together, our results define a mechanism by which intestinal microbes contribute to the metabolic activation and gut toxicity of TCS, and highlight the importance of considering the contributions of the gut microbiota in evaluating the toxic potential of environmental chemicals.


Subject(s)
Bacterial Proteins/antagonists & inhibitors , Carcinogens/antagonists & inhibitors , Colitis/prevention & control , Colorectal Neoplasms/prevention & control , Glucuronidase/antagonists & inhibitors , Glycoside Hydrolase Inhibitors/pharmacology , Triclosan/antagonists & inhibitors , Animals , Anti-Infective Agents, Local/chemistry , Anti-Infective Agents, Local/metabolism , Anti-Infective Agents, Local/toxicity , Anticarcinogenic Agents/chemistry , Anticarcinogenic Agents/pharmacology , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Binding Sites , Biotransformation , Carcinogenesis/drug effects , Carcinogenesis/metabolism , Carcinogens/chemistry , Carcinogens/metabolism , Carcinogens/toxicity , Colitis/chemically induced , Colitis/enzymology , Colitis/microbiology , Colon/drug effects , Colon/microbiology , Colon/pathology , Colorectal Neoplasms/chemically induced , Colorectal Neoplasms/enzymology , Colorectal Neoplasms/microbiology , Gastrointestinal Microbiome/drug effects , Gene Expression , Glucuronidase/chemistry , Glucuronidase/genetics , Glucuronidase/metabolism , Glycoside Hydrolase Inhibitors/chemistry , Humans , Mice , Mice, Inbred C57BL , Models, Molecular , Protein Binding , Protein Conformation, alpha-Helical , Protein Conformation, beta-Strand , Protein Interaction Domains and Motifs , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Triclosan/chemistry , Triclosan/metabolism , Triclosan/toxicity
15.
Front Fungal Biol ; 3: 897954, 2022.
Article in English | MEDLINE | ID: mdl-37746219

ABSTRACT

Aspergillus fumigatus is a potentially deadly opportunistic human pathogen. A. fumigatus has evolved a variety of mechanisms to evade detection by the immune system. For example, the conidium surface is covered in a layer of 1,8-dihydroxynaphthalene (DHN) melanin which masks the antigen macrophages use for recognition. DHN melanin also protects conidia from ultraviolet radiation and gives A. fumigatus conidia their characteristic green-grayish color. Here, we conducted genomic analysis of two closely related white-spore natural variants of A. fumigatus in comparison to two closely related green-spore isolates to identify a genetic basis of the white-spore phenotype. Illumina whole-genome resequencing data of the four isolates was used to identify variants that were shared in the white-spore isolates and different from both the green-spore isolates and the Af293 reference genome (which is also a green-spore isolate). We identified 4,279 single nucleotide variants and 1,785 insertion/deletions fitting this pattern. Among these, we identified 64 variants predicted to be high impact, loss-of-function mutations. One of these variants is a single nucleotide deletion that results in a frameshift in pksP (Afu2g17600), the core biosynthetic gene in the DHN melanin encoding gene cluster. The frameshift mutation in the white-spore isolates leads to a truncated protein in which a phosphopantetheine attachment site (PP-binding domain) is interrupted and an additional PP-binding domain and a thioesterase domain are omitted. Growth rate analysis of white-spore and green-spore isolates at 37°C and 48°C revealed that white-spore isolates are thermosensitive. Growth rate of A. fumigatus Af293 and a pksP null mutant in the Af293 background suggests pksP is not directly involved in the thermosensitivity phenotype. Further, our study identified a mutation in a gene (Afu4g04740) associated with thermal sensitivity in yeasts which could also be responsible for the thermosensitivity of the white-spore mutants. Overall, we used comparative genomics to identify the mutation and protein alterations responsible for the white-spore phenotype of environmental isolates of A. fumigatus.

17.
Ir J Med Sci ; 191(1): 97-102, 2022 Feb.
Article in English | MEDLINE | ID: mdl-33559047

ABSTRACT

INTRODUCTION: COVID-19 was declared a pandemic in March 2020. With the sudden surge in demand for personal protective equipment (PPE), significant concerns regarding the ongoing availability emerged. One solution proposed is re-sterilisation of respirator masks and this has been commenced in some parts of the world. On review of the literature, very little is documented regarding the knowledge of masks and the attitudes of healthcare workers towards using re-sterilised masks. METHODS: A comprehensive questionnaire was used to assess general knowledge and attitudes around facemasks and respirators. RESULTS: There were 190 respondents. There were significant gaps in knowledge and understanding of when particular face masks should be worn. One-third had significant concerns about ongoing availability. One-third had concerns about the quality of the masks as the pandemic continued. Only 10% of respondents underwent formal face-fitting. Eighty percent of respondents stated they would wear a re-sterilised mask. A further 15% would use a re-sterilised mask but required certain reassurances. Five percent of our respondents would not use a re-sterilised mask under any circumstances. DISCUSSION: Ensuring an adequate understanding of face masks is crucial among healthcare workers (HCWs) and this study highlights a need for further education. It also demonstrates a general acceptability among HCWs towards the use of re-sterilised face masks.


Subject(s)
COVID-19 , Masks , Attitude , Health Personnel , Humans , SARS-CoV-2 , Sterilization
18.
BMJ Case Rep ; 14(7)2021 Jul 15.
Article in English | MEDLINE | ID: mdl-34266815

ABSTRACT

A 63-year-old woman was referred to the specialised knee revision clinic with ongoing knee pain after total knee replacement. She incidentally had cobalt and chromium levels measured. These were seen to be elevated. Comprehensive assessment and investigation did not identify any other source of cobalt or chromium. Aseptic loosening of the knee was diagnosed, and the knee was revised. At the time of surgery, the tissue was seen to be darkened consistent with metallosis. Multiple samples excluded infection on extended cultures. Aspirated fluid showed that periprosthetic fluid had elevated cobalt levels. The knee was successfully revised with good symptomatic outcome and significantly, over the course of several months post-revision, the cobalt and chromium levels returned to normal.


Subject(s)
Arthroplasty, Replacement, Knee , Knee Prosthesis , Arthroplasty, Replacement, Knee/adverse effects , Cobalt , Female , Humans , Knee Joint/diagnostic imaging , Knee Joint/surgery , Knee Prosthesis/adverse effects , Middle Aged , Pain , Prosthesis Failure , Reoperation
19.
Front Microbiol ; 12: 691296, 2021.
Article in English | MEDLINE | ID: mdl-34326825

ABSTRACT

Microbes (bacteria, yeasts, molds), in addition to plants and animals, were domesticated for their roles in food preservation, nutrition and flavor. Aspergillus oryzae is a domesticated filamentous fungal species traditionally used during fermentation of Asian foods and beverage, such as sake, soy sauce, and miso. To date, little is known about the extent of genome and phenotypic variation of A. oryzae isolates from different clades. Here, we used long-read Oxford Nanopore and short-read Illumina sequencing to produce a highly accurate and contiguous genome assemble of A. oryzae 14160, an industrial strain from China. To understand the relationship of this isolate, we performed phylogenetic analysis with 90 A. oryzae isolates and 1 isolate of the A. oryzae progenitor, Aspergillus flavus. This analysis showed that A. oryzae 14160 is a member of clade A, in comparison to the RIB 40 type strain, which is a member of clade F. To explore genome variation between isolates from distinct A. oryzae clades, we compared the A. oryzae 14160 genome with the complete RIB 40 genome. Our results provide evidence of independent evolution of the alpha-amylase gene duplication, which is one of the major adaptive mutations resulting from domestication. Synteny analysis revealed that both genomes have three copies of the alpha-amylase gene, but only one copy on chromosome 2 was conserved. While the RIB 40 genome had additional copies of the alpha-amylase gene on chromosomes III, and V, 14160 had a second copy on chromosome II and an third copy on chromosome VI. Additionally, we identified hundreds of lineage specific genes, and putative high impact mutations in genes involved in secondary metabolism, including several of the core biosynthetic genes. Finally, to examine the functional effects of genome variation between strains, we measured amylase activity, proteolytic activity, and growth rate on several different substrates. RIB 40 produced significantly higher levels of amylase compared to 14160 when grown on rice and starch. Accordingly, RIB 40 grew faster on rice, while 14160 grew faster on soy. Taken together, our analyses reveal substantial genome and phenotypic variation within A. oryzae.

20.
ISME J ; 15(12): 3468-3479, 2021 12.
Article in English | MEDLINE | ID: mdl-34108667

ABSTRACT

Understanding how organisms adapt to extreme living conditions is central to evolutionary biology. Dark septate endophytes (DSEs) constitute an important component of the root mycobiome and they are often able to alleviate host abiotic stresses. Here, we investigated the molecular mechanisms underlying the beneficial association between the DSE Laburnicola rhizohalophila and its host, the native halophyte Suaeda salsa, using population genomics. Based on genome-wide Fst (pairwise fixation index) and Vst analyses, which compared the variance in allele frequencies of single-nucleotide polymorphisms (SNPs) and copy number variants (CNVs), respectively, we found a high level of genetic differentiation between two populations. CNV patterns revealed population-specific expansions and contractions. Interestingly, we identified a ~20 kbp genomic island of high divergence with a strong sign of positive selection. This region contains a melanin-biosynthetic polyketide synthase gene cluster linked to six additional genes likely involved in biosynthesis, membrane trafficking, regulation, and localization of melanin. Differences in growth yield and melanin biosynthesis between the two populations grown under 2% NaCl stress suggested that this genomic island contributes to the observed differences in melanin accumulation. Our findings provide a better understanding of the genetic and evolutionary mechanisms underlying the adaptation to saline conditions of the L. rhizohalophila-S. salsa symbiosis.


Subject(s)
Ascomycota , Chenopodiaceae , Genomic Islands , Salt-Tolerant Plants/microbiology , Ascomycota/genetics , Chenopodiaceae/microbiology , Endophytes/genetics , Melanins , Pigmentation
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