RESUMO
The purpose of this scoping review is to map the extent of the current research on how to best structure questions asking respondents to self-identify their sexual orientation and gender identity and to ascertain what further issues about measurement need to be explored. Using the Arksey and O'Malley framework for scoping reviews, 52 articles describing primary research about how to structure sexual orientation and gender identity (SOGI) questions, published in the years 2000-2021, were identified and analyzed. The domain of sexuality being asked about (e.g., self-label vs. behavior) needs to be clarified, and gender identity should be asked through a multipart item differentiating current identity from the sex assigned at birth. The terms used in the response options should be defined and may vary based on the study population or context. Contrary to expectations given the wide range of question formats currently being used in the field, there is considerable consensus around the basic tenets for structuring questions designed to assess SOGI dimensions.
Assuntos
Identidade de Gênero , Minorias Sexuais e de Gênero , Recém-Nascido , Humanos , Feminino , Masculino , Comportamento SexualRESUMO
BACKGROUND: Pichia pastoris has emerged as an important alternative host for producing recombinant biopharmaceuticals, owing to its high cultivation density, low host cell protein burden, and the development of strains with humanized glycosylation. Despite its demonstrated utility, relatively little strain engineering has been performed to improve Pichia, due in part to the limited number and inconsistent frameworks of reported genomes and transcriptomes. Furthermore, the co-mingling of genomic, transcriptomic and fermentation data collected about Komagataella pastoris and Komagataella phaffii, the two strains co-branded as Pichia, has generated confusion about host performance for these genetically distinct species. Generation of comparative high-quality genomes and transcriptomes will enable meaningful comparisons between the organisms, and potentially inform distinct biotechnological utilies for each species. RESULTS: Here, we present a comprehensive and standardized comparative analysis of the genomic features of the three most commonly used strains comprising the tradename Pichia: K. pastoris wild-type, K. phaffii wild-type, and K. phaffii GS115. We used a combination of long-read (PacBio) and short-read (Illumina) sequencing technologies to achieve over 1000X coverage of each genome. Construction of individual genomes was then performed using as few as seven individual contigs to create gap-free assemblies. We found substantial syntenic rearrangements between the species and characterized a linear plasmid present in K. phaffii. Comparative analyses between K. phaffii genomes enabled the characterization of the mutational landscape of the GS115 strain. We identified and examined 35 non-synonomous coding mutations present in GS115, many of which are likely to impact strain performance. Additionally, we investigated transcriptomic profiles of gene expression for both species during cultivation on various carbon sources. We observed that the most highly transcribed genes in both organisms were consistently highly expressed in all three carbon sources examined. We also observed selective expression of certain genes in each carbon source, including many sequences not previously reported as promoters for expression of heterologous proteins in yeasts. CONCLUSIONS: Our studies establish a foundation for understanding critical relationships between genome structure, cultivation conditions and gene expression. The resources we report here will inform and facilitate rational, organism-wide strain engineering for improved utility as a host for protein production.
Assuntos
Perfilação da Expressão Gênica , Genômica , Pichia/genética , Processamento Alternativo , DNA Fúngico/genética , Anotação de Sequência Molecular , Mutação , Pichia/crescimento & desenvolvimento , Pichia/metabolismo , Especificidade da EspécieRESUMO
Oomycetes in the class Saprolegniomycetidae of the Eukaryotic kingdom Stramenopila have evolved as severe pathogens of amphibians, crustaceans, fish and insects, resulting in major losses in aquaculture and damage to aquatic ecosystems. We have sequenced the 63 Mb genome of the fresh water fish pathogen, Saprolegnia parasitica. Approximately 1/3 of the assembled genome exhibits loss of heterozygosity, indicating an efficient mechanism for revealing new variation. Comparison of S. parasitica with plant pathogenic oomycetes suggests that during evolution the host cellular environment has driven distinct patterns of gene expansion and loss in the genomes of plant and animal pathogens. S. parasitica possesses one of the largest repertoires of proteases (270) among eukaryotes that are deployed in waves at different points during infection as determined from RNA-Seq data. In contrast, despite being capable of living saprotrophically, parasitism has led to loss of inorganic nitrogen and sulfur assimilation pathways, strikingly similar to losses in obligate plant pathogenic oomycetes and fungi. The large gene families that are hallmarks of plant pathogenic oomycetes such as Phytophthora appear to be lacking in S. parasitica, including those encoding RXLR effectors, Crinkler's, and Necrosis Inducing-Like Proteins (NLP). S. parasitica also has a very large kinome of 543 kinases, 10% of which is induced upon infection. Moreover, S. parasitica encodes several genes typical of animals or animal-pathogens and lacking from other oomycetes, including disintegrins and galactose-binding lectins, whose expression and evolutionary origins implicate horizontal gene transfer in the evolution of animal pathogenesis in S. parasitica.
Assuntos
Transferência Genética Horizontal , Interações Hospedeiro-Parasita/genética , Oomicetos/genética , Saprolegnia/genética , Virulência/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Evolução Molecular , Peixes/genética , Peixes/parasitologia , Genoma , Oomicetos/classificação , Oomicetos/patogenicidade , Filogenia , Plantas/parasitologia , Saprolegnia/classificação , Saprolegnia/patogenicidadeRESUMO
BACKGROUND: The continued advance of antibiotic resistance threatens the treatment and control of many infectious diseases. This is exemplified by the largest global outbreak of extensively drug-resistant (XDR) tuberculosis (TB) identified in Tugela Ferry, KwaZulu-Natal, South Africa, in 2005 that continues today. It is unclear whether the emergence of XDR-TB in KwaZulu-Natal was due to recent inadequacies in TB control in conjunction with HIV or other factors. Understanding the origins of drug resistance in this fatal outbreak of XDR will inform the control and prevention of drug-resistant TB in other settings. In this study, we used whole genome sequencing and dating analysis to determine if XDR-TB had emerged recently or had ancient antecedents. METHODS AND FINDINGS: We performed whole genome sequencing and drug susceptibility testing on 337 clinical isolates of Mycobacterium tuberculosis collected in KwaZulu-Natal from 2008 to 2013, in addition to three historical isolates, collected from patients in the same province and including an isolate from the 2005 Tugela Ferry XDR outbreak, a multidrug-resistant (MDR) isolate from 1994, and a pansusceptible isolate from 1995. We utilized an array of whole genome comparative techniques to assess the relatedness among strains, to establish the order of acquisition of drug resistance mutations, including the timing of acquisitions leading to XDR-TB in the LAM4 spoligotype, and to calculate the number of independent evolutionary emergences of MDR and XDR. Our sequencing and analysis revealed a 50-member clone of XDR M. tuberculosis that was highly related to the Tugela Ferry XDR outbreak strain. We estimated that mutations conferring isoniazid and streptomycin resistance in this clone were acquired 50 y prior to the Tugela Ferry outbreak (katG S315T [isoniazid]; gidB 130 bp deletion [streptomycin]; 1957 [95% highest posterior density (HPD): 1937-1971]), with the subsequent emergence of MDR and XDR occurring 20 y (rpoB L452P [rifampicin]; pncA 1 bp insertion [pyrazinamide]; 1984 [95% HPD: 1974-1992]) and 10 y (rpoB D435G [rifampicin]; rrs 1400 [kanamycin]; gyrA A90V [ofloxacin]; 1995 [95% HPD: 1988-1999]) prior to the outbreak, respectively. We observed frequent de novo evolution of MDR and XDR, with 56 and nine independent evolutionary events, respectively. Isoniazid resistance evolved before rifampicin resistance 46 times, whereas rifampicin resistance evolved prior to isoniazid only twice. We identified additional putative compensatory mutations to rifampicin in this dataset. One major limitation of this study is that the conclusions with respect to ordering and timing of acquisition of mutations may not represent universal patterns of drug resistance emergence in other areas of the globe. CONCLUSIONS: In the first whole genome-based analysis of the emergence of drug resistance among clinical isolates of M. tuberculosis, we show that the ancestral precursor of the LAM4 XDR outbreak strain in Tugela Ferry gained mutations to first-line drugs at the beginning of the antibiotic era. Subsequent accumulation of stepwise resistance mutations, occurring over decades and prior to the explosion of HIV in this region, yielded MDR and XDR, permitting the emergence of compensatory mutations. Our results suggest that drug-resistant strains circulating today reflect not only vulnerabilities of current TB control efforts but also those that date back 50 y. In drug-resistant TB, isoniazid resistance was overwhelmingly the initial resistance mutation to be acquired, which would not be detected by current rapid molecular diagnostics employed in South Africa that assess only rifampicin resistance.
Assuntos
Antituberculosos/farmacologia , Tuberculose Extensivamente Resistente a Medicamentos/genética , Genoma Bacteriano , Mycobacterium tuberculosis/genética , Adulto , Surtos de Doenças , Tuberculose Extensivamente Resistente a Medicamentos/tratamento farmacológico , Tuberculose Extensivamente Resistente a Medicamentos/epidemiologia , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Mutação , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Análise de Sequência de DNA , África do Sul/epidemiologiaRESUMO
Exceptionally accurate genome reference sequences have proven to be of great value to microbial researchers. Thus, to date, about 1800 bacterial genome assemblies have been "finished" at great expense with the aid of manual laboratory and computational processes that typically iterate over a period of months or even years. By applying a new laboratory design and new assembly algorithm to 16 samples, we demonstrate that assemblies exceeding finished quality can be obtained from whole-genome shotgun data and automated computation. Cost and time requirements are thus dramatically reduced.
Assuntos
Bactérias/genética , Genoma Bacteriano , Biblioteca Genômica , Análise de Sequência de DNA/métodos , AlgoritmosRESUMO
Eliminating the bacterial cloning step has been a major factor in the vastly improved efficiency of massively parallel sequencing approaches. However, this also has made it a technical challenge to produce the modern equivalent of the Fosmid- or BAC-end sequences that were crucial for assembling and analyzing complex genomes during the Sanger-based sequencing era. To close this technology gap, we developed Fosill, a method for converting Fosmids to Illumina-compatible jumping libraries. We constructed Fosmid libraries in vectors with Illumina primer sequences and specific nicking sites flanking the cloning site. Our family of pFosill vectors allows multiplex Fosmid cloning of end-tagged genomic fragments without physical size selection and is compatible with standard and multiplex paired-end Illumina sequencing. To excise the bulk of each cloned insert, we introduced two nicks in the vector, translated them into the inserts, and cleaved them. Recircularization of the vector via coligation of insert termini followed by inverse PCR generates a jumping library for paired-end sequencing with 101-base reads. The yield of unique Fosmid-sized jumps is sufficiently high, and the background of short, incorrectly spaced and chimeric artifacts sufficiently low, to enable applications such as mapping of structural variation and scaffolding of de novo assemblies. We demonstrate the power of Fosill to map genome rearrangements in a cancer cell line and identified three fusion genes that were corroborated by RNA-seq data. Our Fosill-powered assembly of the mouse genome has an N50 scaffold length of 17.0 Mb, rivaling the connectivity (16.9 Mb) of the Sanger-sequencing based draft assembly.
Assuntos
Escherichia coli/genética , Vetores Genéticos/genética , Genoma Bacteriano , Genoma Fúngico , Biblioteca Genômica , Schizosaccharomyces/genética , Análise de Sequência de DNA/métodos , Animais , Rearranjo Gênico , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Deep sequencing technologies have the potential to transform the study of highly variable viral pathogens by providing a rapid and cost-effective approach to sensitively characterize rapidly evolving viral quasispecies. Here, we report on a high-throughput whole HIV-1 genome deep sequencing platform that combines 454 pyrosequencing with novel assembly and variant detection algorithms. In one subject we combined these genetic data with detailed immunological analyses to comprehensively evaluate viral evolution and immune escape during the acute phase of HIV-1 infection. The majority of early, low frequency mutations represented viral adaptation to host CD8+ T cell responses, evidence of strong immune selection pressure occurring during the early decline from peak viremia. CD8+ T cell responses capable of recognizing these low frequency escape variants coincided with the selection and evolution of more effective secondary HLA-anchor escape mutations. Frequent, and in some cases rapid, reversion of transmitted mutations was also observed across the viral genome. When located within restricted CD8 epitopes these low frequency reverting mutations were sufficient to prime de novo responses to these epitopes, again illustrating the capacity of the immune response to recognize and respond to low frequency variants. More importantly, rapid viral escape from the most immunodominant CD8+ T cell responses coincided with plateauing of the initial viral load decline in this subject, suggestive of a potential link between maintenance of effective, dominant CD8 responses and the degree of early viremia reduction. We conclude that the early control of HIV-1 replication by immunodominant CD8+ T cell responses may be substantially influenced by rapid, low frequency viral adaptations not detected by conventional sequencing approaches, which warrants further investigation. These data support the critical need for vaccine-induced CD8+ T cell responses to target more highly constrained regions of the virus in order to ensure the maintenance of immunodominant CD8 responses and the sustained decline of early viremia.
Assuntos
Genoma Viral/genética , Estudo de Associação Genômica Ampla , Infecções por HIV/virologia , HIV-1/genética , Evasão da Resposta Imune/imunologia , Linfócitos T CD8-Positivos/imunologia , Variação Genética , Variação Estrutural do Genoma , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , HIV-1/imunologia , HIV-1/patogenicidade , Humanos , Evasão da Resposta Imune/genética , Análise de Sequência com Séries de Oligonucleotídeos , RNA Viral/análise , Análise de Sequência de RNA , Vacinas Virais/imunologiaRESUMO
OBJECTIVE: To identify and describe evidence on brief emergency department (ED)-delivered behavioural and care process interventions among patients presenting with suicide attempt or acute ideation, substance overdose or psychosis. DESIGN: We employed a scoping review design and searched multiple data sources, clinical trial registries and references lists through March 2023. We included English-language trials and rigorously designed observational studies. In alignment with scoping review guidelines, we did not assess the quality of included studies or rate the strength of evidence of intervention effectiveness. POPULATION: Our population of interest was adults presenting to the ED with suicidality (eg, attempt or acute ideation), any substance overdose or acute psychosis from a primary mental health condition. INTERVENTION: We included studies of brief behavioural or care process interventions delivered in the ED. OUTCOME MEASURES: Health outcomes (eg, symptom reduction), healthcare utilisation and harms. RESULTS: Our search identified 2034 potentially relevant articles. We included 40 studies: 3 systematic reviews and 39 primary studies. Most studies (n=34) examined ED interventions in patients with suicide attempt or suicidal ideation, while eight studies examined interventions in patients with opioid overdose. No studies examined ED interventions in patients with acute psychosis. Most suicide prevention studies reported that brief psychological, psychosocial or screening and triage interventions reduce suicide and suicide attempt following an ED visit. Most clinical trial interventions were multicomponent and included at least one follow-up. All substance overdose studies focused on opioids. These studies often contained medication and referral or consultation components. Multiple studies reported increases in substance use disorder treatment utilisation; evidence on repeat overdose events was limited. CONCLUSIONS: A wide range of multicomponent ED-delivered behavioural health interventions for suicidality and opioid use disorder show short-term improvement on primary outcomes such as suicide reattempt. Few studies on non-opioid substances and psychosis are available.
Assuntos
Overdose de Drogas , Transtornos Psicóticos , Adulto , Humanos , Saúde Mental , Transtornos Psicóticos/terapia , Tentativa de Suicídio/psicologia , Prevenção do Suicídio , Ideação Suicida , Serviço Hospitalar de EmergênciaRESUMO
Here we present a finished sequence of human chromosome 15, together with a high-quality gene catalogue. As chromosome 15 is one of seven human chromosomes with a high rate of segmental duplication, we have carried out a detailed analysis of the duplication structure of the chromosome. Segmental duplications in chromosome 15 are largely clustered in two regions, on proximal and distal 15q; the proximal region is notable because recombination among the segmental duplications can result in deletions causing Prader-Willi and Angelman syndromes. Sequence analysis shows that the proximal and distal regions of 15q share extensive ancient similarity. Using a simple approach, we have been able to reconstruct many of the events by which the current duplication structure arose. We find that most of the intrachromosomal duplications seem to share a common ancestry. Finally, we demonstrate that some remaining gaps in the genome sequence are probably due to structural polymorphisms between haplotypes; this may explain a significant fraction of the gaps remaining in the human genome.
Assuntos
Cromossomos Humanos Par 15/genética , Evolução Molecular , Duplicação Gênica , Animais , Sequência Conservada/genética , Genes , Genoma Humano , Haplótipos/genética , Humanos , Macaca mulatta/genética , Dados de Sequência Molecular , Família Multigênica/genética , Filogenia , Polimorfismo Genético/genética , Análise de Sequência de DNA , Sintenia/genéticaRESUMO
Chromosome 17 is unusual among the human chromosomes in many respects. It is the largest human autosome with orthology to only a single mouse chromosome, mapping entirely to the distal half of mouse chromosome 11. Chromosome 17 is rich in protein-coding genes, having the second highest gene density in the genome. It is also enriched in segmental duplications, ranking third in density among the autosomes. Here we report a finished sequence for human chromosome 17, as well as a structural comparison with the finished sequence for mouse chromosome 11, the first finished mouse chromosome. Comparison of the orthologous regions reveals striking differences. In contrast to the typical pattern seen in mammalian evolution, the human sequence has undergone extensive intrachromosomal rearrangement, whereas the mouse sequence has been remarkably stable. Moreover, although the human sequence has a high density of segmental duplication, the mouse sequence has a very low density. Notably, these segmental duplications correspond closely to the sites of structural rearrangement, demonstrating a link between duplication and rearrangement. Examination of the main classes of duplicated segments provides insight into the dynamics underlying expansion of chromosome-specific, low-copy repeats in the human genome.
Assuntos
Cromossomos Humanos Par 17/genética , Evolução Molecular , Animais , Composição de Bases , Duplicação Gênica , Humanos , Elementos Nucleotídeos Longos e Dispersos/genética , Camundongos , Análise de Sequência de DNA , Elementos Nucleotídeos Curtos e Dispersos/genética , Sintenia/genéticaRESUMO
BACKGROUND: Carbapenem-resistant Enterobacterales (CRE) are an urgent global health threat. Inferring the dynamics of local CRE dissemination is currently limited by our inability to confidently trace the spread of resistance determinants to unrelated bacterial hosts. Whole-genome sequence comparison is useful for identifying CRE clonal transmission and outbreaks, but high-frequency horizontal gene transfer (HGT) of carbapenem resistance genes and subsequent genome rearrangement complicate tracing the local persistence and mobilization of these genes across organisms. METHODS: To overcome this limitation, we developed a new approach to identify recent HGT of large, near-identical plasmid segments across species boundaries, which also allowed us to overcome technical challenges with genome assembly. We applied this to complete and near-complete genome assemblies to examine the local spread of CRE in a systematic, prospective collection of all CRE, as well as time- and species-matched carbapenem-susceptible Enterobacterales, isolated from patients from four US hospitals over nearly 5 years. RESULTS: Our CRE collection comprised a diverse range of species, lineages, and carbapenem resistance mechanisms, many of which were encoded on a variety of promiscuous plasmid types. We found and quantified rearrangement, persistence, and repeated transfer of plasmid segments, including those harboring carbapenemases, between organisms over multiple years. Some plasmid segments were found to be strongly associated with specific locales, thus representing geographic signatures that make it possible to trace recent and localized HGT events. Functional analysis of these signatures revealed genes commonly found in plasmids of nosocomial pathogens, such as functions required for plasmid retention and spread, as well survival against a variety of antibiotic and antiseptics common to the hospital environment. CONCLUSIONS: Collectively, the framework we developed provides a clearer, high-resolution picture of the epidemiology of antibiotic resistance importation, spread, and persistence in patients and healthcare networks.
Assuntos
Carbapenêmicos , Transferência Genética Horizontal , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Humanos , Plasmídeos/genética , Estudos ProspectivosRESUMO
Bacteria are the primary food source of choanoflagellates, the closest known relatives of animals. Studying signaling interactions between the Gram-negative Bacteroidetes bacterium Algoriphagus sp. PR1 and its predator, the choanoflagellate Salpingoeca rosetta, provides a promising avenue for testing hypotheses regarding the involvement of bacteria in animal evolution. Here we announce the complete genome sequence of Algoriphagus sp. PR1 and initial findings from its annotation.
Assuntos
Bacteroidetes/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Genoma Bacteriano , Coanoflagelados/fisiologia , Dados de Sequência Molecular , Análise de Sequência de DNARESUMO
Chromosome 18 appears to have the lowest gene density of any human chromosome and is one of only three chromosomes for which trisomic individuals survive to term. There are also a number of genetic disorders stemming from chromosome 18 trisomy and aneuploidy. Here we report the finished sequence and gene annotation of human chromosome 18, which will allow a better understanding of the normal and disease biology of this chromosome. Despite the low density of protein-coding genes on chromosome 18, we find that the proportion of non-protein-coding sequences evolutionarily conserved among mammals is close to the genome-wide average. Extending this analysis to the entire human genome, we find that the density of conserved non-protein-coding sequences is largely uncorrelated with gene density. This has important implications for the nature and roles of non-protein-coding sequence elements.
Assuntos
Cromossomos Humanos Par 18/genética , DNA/genética , Aneuploidia , Animais , Sequência Conservada/genética , Ilhas de CpG/genética , Éxons/genética , Etiquetas de Sequências Expressas , Genes/genética , Genoma Humano , Humanos , Íntrons/genética , Dados de Sequência Molecular , Análise de Sequência de DNA , SinteniaRESUMO
The COVID-19 pandemic has dramatically transformed the U.S. healthcare landscape. Within psychiatry, a sudden relaxing of insurance and regulatory barriers during the month of March 2020 enabled clinicians practicing in a wide range of settings to quickly adopt virtual care in order to provide critical ongoing mental health supports to both existing and new patients struggling with the pandemic's impact. In this article, we briefly review the extensive literature supporting the effectiveness of telepsychiatry relative to in-person mental health care, and describe how payment and regulatory challenges were the primary barriers preventing more widespread adoption of this treatment modality prior to COVID-19. We then review key changes that were implemented at the federal, state, professional, and insurance levels over a one-month period that helped usher in an unprecedented transformation in psychiatric care delivery, from mostly in-person to mostly virtual. Early quality improvement data regarding virtual visit volumes and clinical insights from our outpatient psychiatry department located within a large, urban, tertiary care academic medical center reflect both the opportunities and challenges of virtual care for patients and providers. Notable benefits have included robust clinical volumes despite social distancing mandates, reduced logistical barrieres to care for many patients, and decreased no-show rates. Finally, we provide clinical suggestions for optimizing telepsychiatry based on our experience, make a call for advocacy to continue the reduced insurance and regulatory restrictions affecting telepsychiatry even once this public health crisis has passed, and pose research questions that can help guide optimal utilization of telepsychiatry as mainstay or adjunct of outpatient psychiatric treatment now and in the future.
Assuntos
Assistência Ambulatorial/organização & administração , Infecções por Coronavirus , Transtornos Mentais , Serviços de Saúde Mental/organização & administração , Pandemias , Pneumonia Viral , Psiquiatria/organização & administração , Telemedicina/organização & administração , COVID-19 , Humanos , Transtornos Mentais/diagnóstico , Transtornos Mentais/terapiaRESUMO
UNLABELLED: Resistance mutations to hepatitis C virus (HCV) nonstructural protein 3 (NS3) protease inhibitors in <1% of the viral quasispecies may still allow >1000-fold viral load reductions upon treatment, consistent with their reported reduced replicative fitness in vitro. Recently, however, an R155K protease mutation was reported as the dominant quasispecies in a treatment-naïve individual, raising concerns about possible full drug resistance. To investigate the prevalence of dominant resistance mutations against specifically targeted antiviral therapy for HCV (STAT-C) in the population, we analyzed HCV genome sequences from 507 treatment-naïve patients infected with HCV genotype 1 from the United States, Germany, and Switzerland. Phylogenetic sequence analysis and viral load data were used to identify the possible spread of replication-competent, drug-resistant viral strains in the population and to infer the consequences of these mutations upon viral replication in vivo. Mutations described to confer resistance to the protease inhibitors Telaprevir, BILN2061, ITMN-191, SCH6 and Boceprevir; the NS5B polymerase inhibitor AG-021541; and to the NS4A antagonist ACH-806 were observed mostly as sporadic, unrelated cases, at frequencies between 0.3% and 2.8% in the population, including two patients with possible multidrug resistance. Collectively, however, 8.6% of the patients infected with genotype 1a and 1.4% of those infected with genotype 1b carried at least one dominant resistance mutation. Viral loads were high in the majority of these patients, suggesting that drug-resistant viral strains might achieve replication levels comparable to nonresistant viruses in vivo. CONCLUSION: Naturally occurring dominant STAT-C resistance mutations are common in treatment-naïve patients infected with HCV genotype 1. Their influence on treatment outcome should further be characterized to evaluate possible benefits of drug resistance testing for individual tailoring of drug combinations when treatment options are limited due to previous nonresponse to peginterferon and ribavirin.
Assuntos
Antivirais/uso terapêutico , Farmacorresistência Viral/genética , Hepacivirus/enzimologia , Hepatite C/tratamento farmacológico , Mutação/genética , Inibidores de Proteases/uso terapêutico , Antivirais/farmacologia , Carbamatos/farmacologia , Carbamatos/uso terapêutico , Estudos de Coortes , Feminino , Testes Genéticos , Hepacivirus/genética , Hepacivirus/patogenicidade , Hepatite C/sangue , Hepatite C/virologia , Humanos , Compostos Macrocíclicos/farmacologia , Compostos Macrocíclicos/uso terapêutico , Masculino , Oligopeptídeos/farmacologia , Oligopeptídeos/uso terapêutico , Feniltioureia/análogos & derivados , Feniltioureia/farmacologia , Feniltioureia/uso terapêutico , Filogenia , Prolina/análogos & derivados , Prolina/farmacologia , Prolina/uso terapêutico , Quinolinas/farmacologia , Quinolinas/uso terapêutico , Tiazóis/farmacologia , Tiazóis/uso terapêutico , Carga Viral , Proteínas não Estruturais Virais/antagonistas & inibidoresRESUMO
The human microbiome, described as an accessory organ because of the crucial functions it provides, is composed of species that are uniquely found in humans1,2. Yet, surprisingly little is known about the impact of routine interpersonal contacts in shaping microbiome composition. In a relatively 'closed' cohort of 287 people from the Fiji Islands, where common barriers to bacterial transmission are absent, we examine putative bacterial transmission in individuals' gut and oral microbiomes using strain-level data from both core single-nucleotide polymorphisms and flexible genomic regions. We find a weak signal of transmission, defined by the inferred sharing of genotypes, across many organisms that, in aggregate, reveals strong transmission patterns, most notably within households and between spouses. We were unable to determine the directionality of transmission nor whether it was direct. We further find that women harbour strains more closely related to those harboured by their familial and social contacts than men, and that transmission patterns of oral-associated and gut-associated microbiota need not be the same. Using strain-level data alone, we are able to confidently predict a subset of spouses, highlighting the role of shared susceptibilities, behaviours or social interactions that distinguish specific links in the social network.
Assuntos
Família , Microbiota , Rede Social , Bactérias/genética , Feminino , Fiji , Microbioma Gastrointestinal/genética , Genômica , Genótipo , Especificidade de Hospedeiro , Humanos , Sequências Repetitivas Dispersas , Masculino , Microbiota/genética , Polimorfismo de Nucleotídeo ÚnicoRESUMO
BACKGROUND: While increasing data on bacterial evolution in controlled environments are available, our understanding of bacterial genome evolution in natural environments is limited. We thus performed full genome analyses on four Listeria monocytogenes, including human and food isolates from both a 1988 case of sporadic listeriosis and a 2000 listeriosis outbreak, which had been linked to contaminated food from a single processing facility. All four isolates had been shown to have identical subtypes, suggesting that a specific L. monocytogenes strain persisted in this processing plant over at least 12 years. While a genome sequence for the 1988 food isolate has been reported, we sequenced the genomes of the 1988 human isolate as well as a human and a food isolate from the 2000 outbreak to allow for comparative genome analyses. RESULTS: The two L. monocytogenes isolates from 1988 and the two isolates from 2000 had highly similar genome backbone sequences with very few single nucleotide (nt) polymorphisms (1 - 8 SNPs/isolate; confirmed by re-sequencing). While no genome rearrangements were identified in the backbone genome of the four isolates, a 42 kb prophage inserted in the chromosomal comK gene showed evidence for major genome rearrangements. The human-food isolate pair from each 1988 and 2000 had identical prophage sequence; however, there were significant differences in the prophage sequences between the 1988 and 2000 isolates. Diversification of this prophage appears to have been caused by multiple homologous recombination events or possibly prophage replacement. In addition, only the 2000 human isolate contained a plasmid, suggesting plasmid loss or acquisition events. Surprisingly, besides the polymorphisms found in the comK prophage, a single SNP in the tRNA Thr-4 prophage represents the only SNP that differentiates the 1988 isolates from the 2000 isolates. CONCLUSION: Our data support the hypothesis that the 2000 human listeriosis outbreak was caused by a L. monocytogenes strain that persisted in a food processing facility over 12 years and show that genome sequencing is a valuable and feasible tool for retrospective epidemiological analyses. Short-term evolution of L. monocytogenes in non-controlled environments appears to involve limited diversification beyond plasmid gain or loss and prophage diversification, highlighting the importance of phages in bacterial evolution.
Assuntos
Evolução Molecular , Genoma Bacteriano , Listeria monocytogenes/genética , Técnicas de Tipagem Bacteriana , Linhagem Celular , DNA Bacteriano/genética , Microbiologia de Alimentos , Humanos , Listeria monocytogenes/classificação , Listeria monocytogenes/crescimento & desenvolvimento , Listeria monocytogenes/isolamento & purificação , Mutação , Plasmídeos/genética , Polimorfismo de Nucleotídeo Único , Prófagos/genética , Alinhamento de Sequência , Análise de Sequência de DNARESUMO
The germline genome of the binucleated ciliate Tetrahymena thermophila undergoes programmed chromosome breakage and massive DNA elimination to generate the somatic genome. Here, we present a complete sequence assembly of the germline genome and analyze multiple features of its structure and its relationship to the somatic genome, shedding light on the mechanisms of genome rearrangement as well as the evolutionary history of this remarkable germline/soma differentiation. Our results strengthen the notion that a complex, dynamic, and ongoing interplay between mobile DNA elements and the host genome have shaped Tetrahymena chromosome structure, locally and globally. Non-standard outcomes of rearrangement events, including the generation of short-lived somatic chromosomes and excision of DNA interrupting protein-coding regions, may represent novel forms of developmental gene regulation. We also compare Tetrahymena's germline/soma differentiation to that of other characterized ciliates, illustrating the wide diversity of adaptations that have occurred within this phylum.
Assuntos
Rearranjo Gênico , Genoma de Protozoário , Tetrahymena thermophila/genética , Análise de Sequência de DNARESUMO
Draft genome sequences of seven enterohepatic Helicobacter species, H. bilis, H. canadensis, H. canis, H. cinaedi, H. winghamensis, H. pullorum, and H. macacae, are presented. These isolates were obtained from clinical patients and a nonhuman primate. Due to potential zoonotic risks, we characterized antibiotic resistance markers and Helicobacter virulence factors.