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1.
J Adv Nurs ; 78(5): 1483-1492, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35266578

RESUMEN

AIM: To evaluate the impact of the COVID-19 pandemic on the emotional and spiritual well-being and resilience of a global sample of Advanced Practice Nurses. DESIGN: A web-based cross-sectional mixed methods study. Survey data were collected from Advanced Practice Nurses globally over a 2-month period ending on 31 August 2020. METHODS: The Warwick-Edinburgh Mental Well-being Scale, FACIT-12 Spiritual Well-being Scale and Connor-Davidson Resilience Scale 10 were used to quantify emotional and spiritual well-being and resilience of Advanced Practice Nurses' globally. The survey was distributed internationally using snowball sampling via a secure platform (Qualtrics). Results were analysed using various bivariate tests for associations and group differences. RESULTS: Nine hundred and twenty-eight Advanced Practice Nurses from 53 countries participated in the study. Study participants reported meaningfully lower scores in resilience and emotional well-being compared with non-pandemic scores. Participants from countries with well-developed Advanced Practice Nurses roles reported lower resilience and well-being scores compared with those from countries where Advanced Practice Nurses roles are still being developed. Each scale revealed significant positive associations with the other scales. CONCLUSIONS: Emotional and spiritual well-being and resilience of Advance Practice Nurses has been significantly impacted during the COVID-19 pandemic. Regardless of their work location, work hours, credential or demographics, the APNs in our study reported lower levels of resilience and mental well-being compared with typical scores on the instruments.


Asunto(s)
COVID-19 , Enfermeras y Enfermeros , COVID-19/epidemiología , Estudios Transversales , Humanos , Pandemias , SARS-CoV-2 , Encuestas y Cuestionarios
2.
BMC Genomics ; 22(1): 204, 2021 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-33757428

RESUMEN

BACKGROUND: Variation in locomotor capacity among animals often reflects adaptations to different environments. Despite evidence that physical performance is heritable, the molecular basis of locomotor performance and performance trade-offs remains poorly understood. In this study we identify the genes, signaling pathways, and regulatory processes possibly responsible for the trade-off between burst performance and endurance observed in Xenopus allofraseri, using a transcriptomic approach. RESULTS: We obtained a total of about 121 million paired-end reads from Illumina RNA sequencing and analyzed 218,541 transcripts obtained from a de novo assembly. We identified 109 transcripts with a significant differential expression between endurant and burst performant individuals (FDR ≤ 0.05 and logFC ≥2), and blast searches resulted in 103 protein-coding genes. We found major differences between endurant and burst-performant individuals in the expression of genes involved in the polymerization and ATPase activity of actin filaments, cellular trafficking, proteoglycans and extracellular proteins secreted, lipid metabolism, mitochondrial activity and regulators of signaling cascades. Remarkably, we revealed transcript isoforms of key genes with functions in metabolism, apoptosis, nuclear export and as a transcriptional corepressor, expressed in either burst-performant or endurant individuals. Lastly, we find two up-regulated transcripts in burst-performant individuals that correspond to the expression of myosin-binding protein C fast-type (mybpc2). This suggests the presence of mybpc2 homoeologs and may have been favored by selection to permit fast and powerful locomotion. CONCLUSION: These results suggest that the differential expression of genes belonging to the pathways of calcium signaling, endoplasmic reticulum stress responses and striated muscle contraction, in addition to the use of alternative splicing and effectors of cellular activity underlie locomotor performance trade-offs. Ultimately, our transcriptomic analysis offers new perspectives for future analyses of the role of single nucleotide variants, homoeology and alternative splicing in the evolution of locomotor performance trade-offs.


Asunto(s)
Perfilación de la Expresión Génica , Transcriptoma , Animales , Anuros , Xenopus , Xenopus laevis
3.
Public Health Nurs ; 38(5): 789-800, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33876506

RESUMEN

OBJECTIVES: To explore factors associated with the impact of COVID-19 on the Latinx population, a Scoping Review of literature was undertaken. DESIGN: A systematic review was conducted utilizing the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Scoping Review (PRISMA ScR) guidelines. A search of databases PubMed, CINAHL, and APA PsycINFO was conducted and included studies through November 23, 2020. SAMPLE: Selected articles were limited to English language, included population data from the US, were specific to the topic of COVID-19, Latinx community findings significantly addressed, and added significant information to the developing narrative not covered elsewhere. RESULTS: Sixteen studies in the final selection included meta-analyses, community-based assessments, and electronic health records reviews of hospital systems and local/state/national public databases. This review describes the prevalence of COVID-19 in the Latinx population, social factors related to disease burden, and the economic implications and disproportionality of COVID-19. CONCLUSIONS: The impact of COVID-19 on the Latinx population is multi-factorial. More research is needed to examine each of these factors in greater detail.


Asunto(s)
COVID-19 , Hispánicos o Latinos , COVID-19/etnología , Disparidades en el Estado de Salud , Hispánicos o Latinos/estadística & datos numéricos , Humanos , Factores Socioeconómicos , Estados Unidos/epidemiología
4.
J Nurse Pract ; 17(6): 702-706, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33642956

RESUMEN

The purpose of this study was to assess the impact of coronavirus disease 2019 on perceived stress experienced by nurse practitioners/nurses and their desire to remain employed as health care providers. A cross-sectional survey of 40 questions was administered between May and September 2020 to a convenience sample of 433 nurse practitioners and nurses in Missouri and Georgia through a Qualtrics (Provo, UT) link provided via their professional organization listserv. Anxiety-related symptoms and perceived helplessness were correlated with personal protective equipment concerns and management approachability. Problematic stress was associated with willingness to leave their current job or the nursing profession altogether.

5.
Lancet ; 393(10185): 2051-2058, 2019 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-30982687

RESUMEN

BACKGROUND: The oligometastatic paradigm suggests that some patients with a limited number of metastases might be cured if all lesions are eradicated. Evidence from randomised controlled trials to support this paradigm is scarce. We aimed to assess the effect of stereotactic ablative radiotherapy (SABR) on survival, oncological outcomes, toxicity, and quality of life in patients with a controlled primary tumour and one to five oligometastatic lesions. METHODS: This randomised, open-label phase 2 study was done at 10 hospitals in Canada, the Netherlands, Scotland, and Australia. Patients aged 18 or older with a controlled primary tumour and one to five metastatic lesions, Eastern Cooperative Oncology Group score of 0-1, and a life expectancy of at least 6 months were eligible. After stratifying by the number of metastases (1-3 vs 4-5), we randomly assigned patients (1:2) to receive either palliative standard of care treatments alone (control group), or standard of care plus SABR to all metastatic lesions (SABR group), using a computer-generated randomisation list with permuted blocks of nine. Neither patients nor physicians were masked to treatment allocation. The primary endpoint was overall survival. We used a randomised phase 2 screening design with a two-sided α of 0·20 (wherein p<0·20 designates a positive trial). All analyses were intention to treat. This study is registered with ClinicalTrials.gov, number NCT01446744. FINDINGS: 99 patients were randomised between Feb 10, 2012, and Aug 30, 2016. Of 99 patients, 33 (33%) were assigned to the control group and 66 (67%) to the SABR group. Two (3%) patients in the SABR group did not receive allocated treatment and withdrew from the trial; two (6%) patients in the control group also withdrew from the trial. Median follow-up was 25 months (IQR 19-54) in the control group versus 26 months (23-37) in the SABR group. Median overall survival was 28 months (95% CI 19-33) in the control group versus 41 months (26-not reached) in the SABR group (hazard ratio 0·57, 95% CI 0·30-1·10; p=0·090). Adverse events of grade 2 or worse occurred in three (9%) of 33 controls and 19 (29%) of 66 patients in the SABR group (p=0·026), an absolute increase of 20% (95% CI 5-34). Treatment-related deaths occurred in three (4·5%) of 66 patients after SABR, compared with none in the control group. INTERPRETATION: SABR was associated with an improvement in overall survival, meeting the primary endpoint of this trial, but three (4·5%) of 66 patients in the SABR group had treatment-related death. Phase 3 trials are needed to conclusively show an overall survival benefit, and to determine the maximum number of metastatic lesions wherein SABR provides a benefit. FUNDING: Ontario Institute for Cancer Research and London Regional Cancer Program Catalyst Grant.


Asunto(s)
Metástasis de la Neoplasia/radioterapia , Cuidados Paliativos , Radiocirugia , Anciano , Supervivencia sin Enfermedad , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia/terapia , Radiocirugia/efectos adversos , Radiocirugia/métodos , Radiocirugia/mortalidad , Análisis de Supervivencia , Resultado del Tratamiento
6.
Environ Sci Technol ; 54(24): 15935-15945, 2020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33227200

RESUMEN

Exposure of male fish to estrogenic substances from wastewater treatment works (WwTWs) results in feminization and reduced reproductive fitness. Nevertheless, self-sustaining populations of roach (Rutilus rutilus) inhabit river stretches polluted with estrogenic WwTW effluents. In this study, we examine whether such roach populations have evolved adaptations to tolerate estrogenic pollution by comparing frequency differences in single-nucleotide polymorphisms (SNPs) between populations sampled from rivers receiving either high- or low-level WwTW discharges. SNPs within 36 "candidate" genes, selected for their involvement in estrogenic responses, and 120 SNPs in reference genes were genotyped in 465 roaches. There was no evidence for selection in highly estrogen-dependent candidate genes, including those for the estrogen receptors, aromatases, and vitellogenins. The androgen receptor (ar) and cytochrome P450 1A genes were associated with large shifts in allele frequencies between catchments and in individual populations, but there is no clear link to estrogen pollution. Selection at ar in the effluent-dominated River Lee may have resulted from historical contamination with endocrine-disrupting pesticides. Critically, although our results suggest population-specific selection including at genes related to endocrine disruption, there was no strong evidence that the selection resulted from exposure to estrogen pollution.


Asunto(s)
Cyprinidae , Contaminantes Químicos del Agua , Animales , Cyprinidae/genética , Estrógenos , Estrona , Humanos , Masculino , Ríos , Vitelogeninas , Contaminantes Químicos del Agua/análisis
7.
EMBO Rep ; 17(1): 79-93, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26582768

RESUMEN

Maintenance of the correct level and organisation of nucleosomes is crucial for genome function. Here, we uncover a role for a conserved bromodomain AAA-ATPase, Abo1, in the maintenance of nucleosome architecture in fission yeast. Cells lacking abo1(+) experience both a reduction and mis-positioning of nucleosomes at transcribed sequences in addition to increased intragenic transcription, phenotypes that are hallmarks of defective chromatin re-establishment behind RNA polymerase II. Abo1 is recruited to gene sequences and associates with histone H3 and the histone chaperone FACT. Furthermore, the distribution of Abo1 on chromatin is disturbed by impaired FACT function. The role of Abo1 extends to some promoters and also to silent heterochromatin. Abo1 is recruited to pericentromeric heterochromatin independently of the HP1 ortholog, Swi6, where it enforces proper nucleosome occupancy. Consequently, loss of Abo1 alleviates silencing and causes elevated chromosome mis-segregation. We suggest that Abo1 provides a histone chaperone function that maintains nucleosome architecture genome-wide.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Cromatina/genética , Cromatina/metabolismo , Nucleosomas/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Adenosina Trifosfatasas/química , Adenosina Trifosfatasas/genética , Ensamble y Desensamble de Cromatina , Proteínas Cromosómicas no Histona/metabolismo , Segregación Cromosómica , ADN Intergénico , Silenciador del Gen , Chaperonas de Histonas/genética , Chaperonas de Histonas/metabolismo , Histonas/genética , Histonas/metabolismo , Nucleosomas/genética , Regiones Promotoras Genéticas , ARN Polimerasa II/genética , Proteínas de Schizosaccharomyces pombe/química , Proteínas de Schizosaccharomyces pombe/genética , Factores de Transcripción/metabolismo , Transcripción Genética
8.
J Interprof Care ; 32(4): 481-489, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29513119

RESUMEN

Essential for future healthcare professionals (HCPs) to delivering ethical and empathetic patient-centred care (PCC) as a team is the understanding of appropriate shared decision-making (SDM) responses when facilitating discussions with patients and family members. The purpose of this study was to evaluate undergraduate students' perspectives about HCPs' use of SDM as described in a case-study reflection assignment. An exploratory qualitative approach was used to analyse student-reflection assignments. The sample included 42 undergraduate students enrolled in an interprofessional education (IPE) course at a Midwest university based in the United States. Data consisted of student responses in a course reflection assignment that captured their perspectives about recommended SDM responses by HCPs. Student assignments were randomly selected using stratified sampling to provide representation of eight HCP roles. Analysis revealed two themes related to students' use of SDM responses. Results provide evidence supporting the tenet that through IPE, healthcare students can develop an understanding of SDM and ethical principles related to PCC.

9.
Mol Biol Evol ; 33(8): 2002-15, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27189558

RESUMEN

The Microsporidia are a major group of intracellular fungi and important parasites of animals including insects, fish, and immunocompromised humans. Microsporidian genomes have undergone extreme reductive evolution but there are major differences in genome size and structure within the group: some are prokaryote-like in size and organisation (<3 Mb of gene-dense sequence) while others have more typically eukaryotic genome architectures. To gain fine-scale, population-level insight into the evolutionary dynamics of these tiny eukaryotic genomes, we performed the broadest microsporidian population genomic study to date, sequencing geographically isolated strains of Spraguea, a marine microsporidian infecting goosefish worldwide. Our analysis revealed that population structure across the Atlantic Ocean is associated with a conserved difference in ploidy, with American and Canadian isolates sharing an ancestral whole genome duplication that was followed by widespread pseudogenisation and sorting-out of paralogue pairs. While past analyses have suggested de novo gene formation of microsporidian-specific genes, we found evidence for the origin of new genes from noncoding sequence since the divergence of these populations. Some of these genes experience selective constraint, suggesting the evolution of new functions and local host adaptation. Combining our data with published microsporidian genomes, we show that nucleotide composition across the phylum is shaped by a mutational bias favoring A and T nucleotides, which is opposed by an evolutionary force favoring an increase in genomic GC content. This study reveals ongoing dramatic reorganization of genome structure and the evolution of new gene functions in modern microsporidians despite extensive genomic streamlining in their common ancestor.


Asunto(s)
Microsporidios/genética , Evolución Biológica , Biología Computacional , Evolución Molecular , Duplicación de Gen , Variación Genética , Genoma Fúngico , Genómica/métodos , Metagenómica , Filogenia , Filogeografía
10.
Thorax ; 2017 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-28844058

RESUMEN

While Pseudomonas aeruginosa (PA) cross-infection is well documented among patients with cystic fibrosis (CF), the equivalent risk among patients with non-CF bronchiectasis (NCFB) is unclear, particularly those managed alongside patients with CF. We performed analysis of PA within a single centre that manages an unsegregated NCFB cohort alongside a segregated CF cohort. We found no evidence of cross-infection between the two cohorts or within the segregated CF cohort. However, within the unsegregated NCFB cohort, evidence of cross-infection was found between three (of 46) patients. While we do not presently advocate any change in the management of our NCFB cohort, longitudinal surveillance is clearly warranted.

11.
Environ Microbiol ; 19(5): 2077-2089, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28345194

RESUMEN

Glycolysis and oxidative phosphorylation are the fundamental pathways of ATP generation in eukaryotes. Yet in microsporidia, endoparasitic fungi living at the limits of cellular streamlining, oxidative phosphorylation has been lost: energy is obtained directly from the host or, during the dispersive spore stage, via glycolysis. It was therefore surprising when the first sequenced genome from the Enterocytozoonidae - a major family of human and animal-infecting microsporidians - appeared to have lost genes for glycolysis. Here, we sequence and analyse genomes from additional members of this family, shedding new light on their unusual biology. Our survey includes the genome of Enterocytozoon hepatopenaei, a major aquacultural parasite currently causing substantial economic losses in shrimp farming, and Enterospora canceri, a pathogen that lives exclusively inside epithelial cell nuclei of its crab host. Our analysis of gene content across the clade suggests that Ent. canceri's adaptation to intranuclear life is underpinned by the expansion of transporter families. We demonstrate that this entire lineage of pathogens has lost glycolysis and, uniquely amongst eukaryotes, lacks any obvious intrinsic means of generating energy. Our study provides an important resource for the investigation of host-pathogen interactions and reductive evolution in one of the most medically and economically important microsporidian lineages.


Asunto(s)
Enterocytozoon/metabolismo , Genoma de Protozoos/genética , Glucólisis/genética , Hexoquinasa/genética , Interacciones Huésped-Parásitos/fisiología , Fosforilación Oxidativa , Penaeidae/parasitología , Animales , Secuencia de Bases , Evolución Biológica , Enterocytozoon/genética , Enterocytozoon/patogenicidad , Humanos , Microsporidiosis/parasitología , Filogenia , Análisis de Secuencia de ADN
12.
BMC Microbiol ; 17(1): 163, 2017 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-28732479

RESUMEN

BACKGROUND: The World Health Organization has categorized plague as a re-emerging disease and the potential for Yersinia pestis to also be used as a bioweapon makes the identification of new drug targets against this pathogen a priority. Environmental temperature is a key signal which regulates virulence of the bacterium. The bacterium normally grows outside the human host at 28 °C. Therefore, understanding the mechanisms that the bacterium used to adapt to a mammalian host at 37 °C is central to the development of vaccines or drugs for the prevention or treatment of human disease. RESULTS: Using a library of over 1 million Y. pestis CO92 random mutants and transposon-directed insertion site sequencing, we identified 530 essential genes when the bacteria were cultured at 28 °C. When the library of mutants was subsequently cultured at 37 °C we identified 19 genes that were essential at 37 °C but not at 28 °C, including genes which encode proteins that play a role in enabling functioning of the type III secretion and in DNA replication and maintenance. Using genome-scale metabolic network reconstruction we showed that growth conditions profoundly influence the physiology of the bacterium, and by combining computational and experimental approaches we were able to identify 54 genes that are essential under a broad range of conditions. CONCLUSIONS: Using an integrated computational-experimental approach we identify genes which are required for growth at 37 °C and under a broad range of environments may be the best targets for the development of new interventions to prevent or treat plague in humans.


Asunto(s)
Proteínas Bacterianas/genética , Biología Computacional/métodos , Genes Esenciales , Peste/microbiología , Yersinia pestis/genética , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica , Humanos , Mutación , Yersinia pestis/crecimiento & desarrollo , Yersinia pestis/metabolismo
13.
Proc Natl Acad Sci U S A ; 111(52): 18787-92, 2014 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-25516986

RESUMEN

Seasonal behavior is important for fitness in temperate environments but it is unclear how progeny gain their initial seasonal entrainment. Plants use temperature signals to measure time of year, and changes to life histories are therefore an important consequence of climate change. Here we show that in Arabidopsis the current and prior temperature experience of the mother plant is used to control germination of progeny seeds, via the activation of the florigen Flowering Locus T (FT) in fruit tissues. We demonstrate that maternal past and current temperature experience are transduced to the FT locus in silique phloem. In turn, FT controls seed dormancy through inhibition of proanthocyanidin synthesis in fruits, resulting in altered seed coat tannin content. Our data reveal that maternal temperature history is integrated through FT in the fruit to generate a metabolic signal that entrains the behavior of progeny seeds according to time of year.


Asunto(s)
Arabidopsis/fisiología , Sitios Genéticos/fisiología , Latencia en las Plantas/fisiología , Semillas/metabolismo , Transducción de Señal/fisiología , Temperatura , Florigena/metabolismo , Floema/genética , Floema/metabolismo , Proantocianidinas/biosíntesis , Proantocianidinas/genética , Semillas/genética
14.
Proc Natl Acad Sci U S A ; 110(19): 7636-41, 2013 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-23610415

RESUMEN

Biofuels are the most immediate, practical solution for mitigating dependence on fossil hydrocarbons, but current biofuels (alcohols and biodiesels) require significant downstream processing and are not fully compatible with modern, mass-market internal combustion engines. Rather, the ideal biofuels are structurally and chemically identical to the fossil fuels they seek to replace (i.e., aliphatic n- and iso-alkanes and -alkenes of various chain lengths). Here we report on production of such petroleum-replica hydrocarbons in Escherichia coli. The activity of the fatty acid (FA) reductase complex from Photorhabdus luminescens was coupled with aldehyde decarbonylase from Nostoc punctiforme to use free FAs as substrates for alkane biosynthesis. This combination of genes enabled rational alterations to hydrocarbon chain length (Cn) and the production of branched alkanes through upstream genetic and exogenous manipulations of the FA pool. Genetic components for targeted manipulation of the FA pool included expression of a thioesterase from Cinnamomum camphora (camphor) to alter alkane Cn and expression of the branched-chain α-keto acid dehydrogenase complex and ß-keto acyl-acyl carrier protein synthase III from Bacillus subtilis to synthesize branched (iso-) alkanes. Rather than simply reconstituting existing metabolic routes to alkane production found in nature, these results demonstrate the ability to design and implement artificial molecular pathways for the production of renewable, industrially relevant fuel molecules.


Asunto(s)
Biocombustibles , Biotecnología/métodos , Escherichia coli/metabolismo , Ácidos Grasos no Esterificados/química , Alcanos/química , Bacillus subtilis/enzimología , Carbono/química , Cinnamomum/enzimología , Ingeniería Genética/métodos , Datos de Secuencia Molecular , Nostoc/enzimología , Photorhabdus/enzimología , Biología Sintética/métodos
15.
Physiol Genomics ; 47(9): 420-31, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26082144

RESUMEN

Estrogenic chemicals are major contaminants of surface waters and can threaten the sustainability of natural fish populations. Characterization of the global molecular mechanisms of toxicity of environmental contaminants has been conducted primarily in model species rather than species with limited existing transcriptomic or genomic sequence information. We aimed to investigate the global mechanisms of toxicity of an endocrine disrupting chemical of environmental concern [17ß-estradiol (E2)] using high-throughput RNA sequencing (RNA-Seq) in an environmentally relevant species, brown trout (Salmo trutta). We exposed mature males to measured concentrations of 1.94, 18.06, and 34.38 ng E2/l for 4 days and sequenced three individual liver samples per treatment using an Illumina HiSeq 2500 platform. Exposure to 34.4 ng E2/L resulted in 2,113 differentially regulated transcripts (FDR < 0.05). Functional analysis revealed upregulation of processes associated with vitellogenesis, including lipid metabolism, cellular proliferation, and ribosome biogenesis, together with a downregulation of carbohydrate metabolism. Using real-time quantitative PCR, we validated the expression of eight target genes and identified significant differences in the regulation of several known estrogen-responsive transcripts in fish exposed to the lower treatment concentrations (including esr1 and zp2.5). We successfully used RNA-Seq to identify highly conserved responses to estrogen and also identified some estrogen-responsive transcripts that have been less well characterized, including nots and tgm2l. These results demonstrate the potential application of RNA-Seq as a valuable tool for assessing mechanistic effects of pollutants in ecologically relevant species for which little genomic information is available.


Asunto(s)
Disruptores Endocrinos/farmacología , Estradiol/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Hígado/efectos de los fármacos , Oncorhynchus/genética , Animales , Relación Dosis-Respuesta a Droga , Ecotoxicología/métodos , Femenino , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Hígado/fisiología , Masculino , Contaminantes Químicos del Agua/farmacología
16.
BMC Genomics ; 16: 750, 2015 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-26438044

RESUMEN

BACKGROUND: Cronobacter sakazakii is a member of the genus Cronobacter that has frequently been isolated from powdered infant formula (PIF) and linked with rare but fatal neonatal infections such as meningitis and necrotising enterocolitis. The Cronobacter MLST scheme has reported over 400 sequence types and 42 clonal complexes; however C. sakazakii clonal complex 4 (CC4) has been linked strongly with neonatal infections, especially meningitis. There have been a number of reported Cronobacter outbreaks over the last three decades. The largest outbreak of C. sakazakii was in a neonatal intensive care unit (NICU) in France (1994) that lasted over 3 months and claimed the lives of three neonates. The present study used whole genome sequencing data of 26 isolates obtained from this outbreak to reveal their relatedness. This study is first of its kind to use whole genome sequencing data to analyse a Cronobacter outbreak. METHODS: Whole genome sequencing data was generated for 26 C. sakazakii isolates on the Illumina MiSeq platform. The whole genome phylogeny was determined using Mugsy and RaxML. SNP calls were determined using SMALT and SAMtools, and filtered using VCFtools. RESULTS: The whole genome phylogeny suggested 3 distant clusters of C. sakazakii isolates were associated with the outbreak. SNP typing and phylogeny indicate the source of the C. sakazakii could have been from extrinsic contamination of reconstituted infant formula from the NICU environment and personnel. This pool of strains would have contributed to the prolonged duration of the outbreak, which was up to 3 months. Furthermore 3 neonates were co-infected with C. sakazakii from two different genotype clusters. CONCLUSION: The genomic investigation revealed the outbreak consisted of an heterogeneous population of C. sakazakii isolates. The source of the outbreak was not identified, but probably was due to environmental and personnel reservoirs resulting in extrinsic contamination of the neonatal feeds. It also indicated that C. sakazakii isolates from different genotype clusters have the ability to co-infect neonates.


Asunto(s)
Cronobacter sakazakii/genética , Infección Hospitalaria , Brotes de Enfermedades , Infecciones por Enterobacteriaceae/epidemiología , Infecciones por Enterobacteriaceae/microbiología , Unidades de Cuidado Intensivo Neonatal , Cronobacter sakazakii/clasificación , Infecciones por Enterobacteriaceae/historia , Francia/epidemiología , Genoma Bacteriano , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Historia del Siglo XX , Humanos , Lactante , Recién Nacido , Filogenia , Polimorfismo de Nucleótido Simple
17.
BMC Genomics ; 16: 983, 2015 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-26589282

RESUMEN

BACKGROUND: Trachipleistophora hominis was isolated from an HIV/AIDS patient and is a member of a highly successful group of obligate intracellular parasites. METHODS: Here we have investigated the evolution of the parasite and the interplay between host and parasite gene expression using transcriptomics of T. hominis-infected rabbit kidney cells. RESULTS: T. hominis has about 30% more genes than small-genome microsporidians. Highly expressed genes include those involved in growth, replication, defence against oxidative stress, and a large fraction of uncharacterised genes. Chaperones are also highly expressed and may buffer the deleterious effects of the large number of non-synonymous mutations observed in essential T. hominis genes. Host expression suggests a general cellular shutdown upon infection, but ATP, amino sugar and nucleotide sugar production appear enhanced, potentially providing the parasite with substrates it cannot make itself. Expression divergence of duplicated genes, including transporters used to acquire host metabolites, demonstrates ongoing functional diversification during microsporidian evolution. We identified overlapping transcription at more than 100 loci in the sparse T. hominis genome, demonstrating that this feature is not caused by genome compaction. The detection of additional transposons of insect origin strongly suggests that the natural host for T. hominis is an insect. CONCLUSIONS: Our results reveal that the evolution of contemporary microsporidian genomes is highly dynamic and innovative. Moreover, highly expressed T. hominis genes of unknown function include a cohort that are shared among all microsporidians, indicating that some strongly conserved features of the biology of these enormously successful parasites remain uncharacterised.


Asunto(s)
Perfilación de la Expresión Génica , Interacciones Huésped-Patógeno/genética , Microsporidios/genética , Transcriptoma , Alelos , Animales , Línea Celular , Células Cultivadas , Biología Computacional/métodos , Elementos Transponibles de ADN , Diploidia , Evolución Molecular , Regulación Fúngica de la Expresión Génica , Frecuencia de los Genes , Transferencia de Gen Horizontal , Genes Fúngicos , Genoma Fúngico , Insectos/genética , Insectos/microbiología , Estadios del Ciclo de Vida/genética , Microsporidios/crecimiento & desarrollo , Microsporidios/metabolismo , Familia de Multigenes , Filogenia , Polimorfismo de Nucleótido Simple , Empalme del ARN , Conejos , Reproducibilidad de los Resultados , Transcripción Genética
18.
New Phytol ; 205(2): 642-52, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25412428

RESUMEN

Environmental changes during seed production are important drivers of lot-to-lot variation in seed behaviour and enable wild species to time their life history with seasonal cues. Temperature during seed set is the dominant environmental signal determining the depth of primary dormancy, although the mechanisms though which temperature changes impart changes in dormancy state are still only partly understood. We used molecular, genetic and biochemical techniques to examine the mechanism through which temperature variation affects Arabidopsis thaliana seed dormancy. Here we show that, in Arabidopsis, low temperatures during seed maturation result in an increase in phenylpropanoid gene expression in seeds and that this correlates with higher concentrations of seed coat procyanidins. Lower maturation temperatures cause differences in coat permeability to tetrazolium, and mutants with increased seed coat permeability and/or low procyanidin concentrations are less able to enter strongly dormant states after exposure to low temperatures during seed maturation. Our data show that maternal temperature signalling regulates seed coat properties, and this is an important pathway through which the environmental signals control primary dormancy depth.


Asunto(s)
Arabidopsis/fisiología , Latencia en las Plantas , Semillas/crecimiento & desarrollo , Arabidopsis/metabolismo , Proteínas de Arabidopsis , Flavonoides/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Germinación , Semillas/metabolismo , Temperatura
19.
EMBO Rep ; 14(8): 711-7, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23835508

RESUMEN

We have applied chromatin sequencing technology to the euryarchaeon Thermococcus kodakarensis, which is known to possess histone-like proteins. We detect positioned chromatin particles of variable sizes associated with lengths of DNA differing as multiples of 30 bp (ranging from 30 bp to >450 bp) consistent with formation from dynamic polymers of the archaeal histone dimer. T. kodakarensis chromatin particles have distinctive underlying DNA sequence suggesting a genomic particle-positioning code and are excluded from gene-regulatory DNA suggesting a functional organization. Beads-on-a-string chromatin is therefore conserved between eukaryotes and archaea but can derive from deployment of histone-fold proteins in a variety of multimeric forms.


Asunto(s)
Proteínas Arqueales/química , ADN de Archaea/química , Genoma Arqueal , Histonas/química , Nucleosomas/química , Thermococcus/genética , Proteínas Arqueales/genética , Proteínas Arqueales/metabolismo , ADN de Archaea/genética , ADN de Archaea/metabolismo , Histonas/genética , Histonas/metabolismo , Conformación de Ácido Nucleico , Nucleosomas/genética , Nucleosomas/metabolismo , Pliegue de Proteína , Multimerización de Proteína , Thermococcus/metabolismo
20.
BMC Infect Dis ; 15: 449, 2015 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-26497222

RESUMEN

BACKGROUND: The most common cause of Gram-negative bacterial neonatal meningitis is E. coli K1. It has a mortality rate of 10-15 %, and neurological sequelae in 30-50 % of cases. Infections can be attributable to nosocomial sources, however the pre-colonisation of enteral feeding tubes has not been considered as a specific risk factor. METHODS: Thirty E. coli strains, which had been isolated in an earlier study, from the residual lumen liquid and biofilms of neonatal nasogastric feeding tubes were genotyped using pulsed-field gel electrophoresis, and 7-loci multilocus sequence typing. Potential pathogenicity and biofilm associated traits were determined using specific PCR probes, genome analysis, and in vitro tissue culture assays. RESULTS: The E. coli strains clustered into five pulsotypes, which were genotyped as sequence types (ST) 95, 73, 127, 394 and 2076 (Achman scheme). The extra-intestinal pathogenic E. coli (ExPEC) phylogenetic group B2 ST95 serotype O1:K1:NM strains had been isolated over a 2 week period from 11 neonates who were on different feeding regimes. The E. coli K1 ST95 strains encoded for various virulence traits associated with neonatal meningitis and extracellular matrix formation. These strains attached and invaded intestinal, and both human and rat brain cell lines, and persisted for 48 h in U937 macrophages. E. coli STs 73, 394 and 2076 also persisted in macrophages and invaded Caco-2 and human brain cells, but only ST394 invaded rat brain cells. E. coli ST127 was notable as it did not invade any cell lines. CONCLUSIONS: Routes by which E. coli K1 can be disseminated within a neonatal intensive care unit are uncertain, however the colonisation of neonatal enteral feeding tubes may be one reservoir source which could constitute a serious health risk to neonates following ingestion.


Asunto(s)
ADN Bacteriano/análisis , Infecciones por Escherichia coli/diagnóstico , Escherichia coli/genética , Meningitis/diagnóstico , Animales , Antibacterianos/farmacología , Células CACO-2 , Línea Celular , Electroforesis en Gel de Campo Pulsado , Escherichia coli/efectos de los fármacos , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/genética , Genotipo , Humanos , Intubación Gastrointestinal , Meningitis/microbiología , Tipificación de Secuencias Multilocus , Filogenia , Ratas , Serotipificación , Factores de Virulencia/genética
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