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BACKGROUND: For pathogens which cause infections that present asymptomatically, evaluating vaccine efficacy (VE) against asymptomatic infection is important for understanding a vaccine's potential epidemiological impact. Regular testing for subclinical infections is a potentially valuable strategy but its success hinges on participant adherence and minimising false positives. This paper describes the implementation and adherence to weekly testing in a COVID-19 vaccine trial. METHODS: COV002 was a phase 2/3 trial assessing the ChAdOx1 nCoV-19 vaccine against SARS-CoV-2. Asymptomatic infections were detected using weekly self-administered swabs for RT-PCR testing. We analysed adherence using mixed-effects regression models and estimated the probability of true and false positive asymptomatic infections using estimates of adherence and testing characteristics. FINDINGS: 356,551 tests were self-administered by 10,811 participants during the 13-month follow-up. Median adherence was 75.0% (IQR 42·6-90·9), which translated to a 74·5% (IQR 50·9-78·8) probability of detecting a positive asymptomatic infection during the swabbing period, and between 21 and 96 false positives during VE evaluation. The odds of returning a swab declined by 8% per week and further after testing positive and unblinding. Adherence was higher in older age groups, females and non-healthcare workers. INTERPRETATION: The COV002 trial demonstrated the feasibility of running a long-term regular asymptomatic testing strategy. This information could be valuable for designing future phase III vaccine trials in which infection is an outcome. FUNDING: UK Research and Innovation, National Institutes for Health Research (NIHR), Coalition for Epidemic Preparedness Innovations, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midland's NIHR Clinical Research Network, AstraZeneca.
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Infecciones Asintomáticas , Vacunas contra la COVID-19 , COVID-19 , SARS-CoV-2 , Humanos , COVID-19/prevención & control , COVID-19/epidemiología , COVID-19/diagnóstico , Femenino , Masculino , Vacunas contra la COVID-19/administración & dosificación , Adulto , Persona de Mediana Edad , SARS-CoV-2/inmunología , ChAdOx1 nCoV-19 , Eficacia de las Vacunas/estadística & datos numéricos , Adulto Joven , Anciano , Cooperación del Paciente/estadística & datos numéricosRESUMEN
BACKGROUND: Chronic nausea and vomiting syndromes (CNVS), gastroparesis and functional dyspepsia (FD) are complex disorders. Body Surface Gastric Mapping (BSGM), a new test of gastric function, using Gastric Alimetry® (Alimetry, New Zealand) may be useful for de-escalating healthcare utilisation. This study aimed to define healthcare costs and estimate health economic impacts of implementing this test in patients with chronic gastroduodenal symptoms. METHODS: Consecutive patients at a tertiary referral centre evaluated with Gastric Alimetry were included. Frequency and cost data relating to medical investigations, hospital and outpatient presentations were evaluated. Costs of healthcare utilisation were calculated, and the potential cost savings of implementing Gastric Alimetry within a diagnostic decision-tree model were estimated. RESULTS: Overall, 31 consecutive patients (mean age 36.1 years; 83.9% female; predominant symptoms: nausea [83.9%], pain [61.3%], vomiting [67.7%] and bloating [35.5%]) completed Gastric Alimetry testing. Repeat gastroscopy and abdominal CT rates were 29% (8/28) and 85% (11/13), respectively. Gastric Alimetry testing identified spectral abnormalities in 45.2% of patients, and symptom profiling classified a further 29.1% of patients. Median annualised cost difference after test introduction was NZ$-12,032. Estimated reductions in investigation-related costs when incorporating Gastric Alimetry into the diagnostic workflow model were approximately NZ$1,300 per patient. CONCLUSIONS: Healthcare utilisation and confirmatory testing rates remain high in nausea and vomiting syndromes. This study presents real-world data, together with a decision-tree analysis, showing Gastric Alimetry can streamline clinical care pathways, resulting in reduced healthcare utilisation and cost.
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Náusea , Vómitos , Humanos , Femenino , Masculino , Adulto , Vómitos/economía , Vómitos/diagnóstico , Náusea/economía , Náusea/diagnóstico , Náusea/etiología , Persona de Mediana Edad , Gastroparesia/diagnóstico , Gastroparesia/economía , Costos de la Atención en Salud/estadística & datos numéricos , Dispepsia/economía , Dispepsia/diagnóstico , Nueva Zelanda , Análisis Costo-Beneficio , Adulto Joven , Árboles de DecisiónRESUMEN
INTRODUCTION: British military personnel deploy internationally to areas with high levels of ambient air pollution. Air pollution can cause acute respiratory symptoms which lead to concern about potential long-lasting health effects. There is a requirement for evidence-based policy on chronic respiratory disease associated with military deployments to areas with poor air quality (AQ). This literature review examines the published evidence relating to the development of chronic respiratory disease in military personnel after exposure to poor AQ while deployed. METHODS: A literature search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Embase, MEDLINE and Global health databases were searched for English language studies published since 2014 examining the respiratory health of military personnel deployed to Southwest Asia since 2001. A quality appraisal of selected articles was conducted using the Critical Appraisals Skills Programme checklist and a descriptive review completed. RESULTS: Eleven studies were found, eight of which had objective outcome measures. Two prospective cohort studies were included; the remainder of the data were retrospective. CONCLUSION: High rates of respiratory symptoms are reported by personnel who deploy to areas of poor AQ, giving rise to high levels of concern. Spirometry testing has found mild deficits, mostly of an obstructive nature, in a third of those with ongoing symptoms post deployment. These have not been consistently linked with deployment length. An increased risk of asthma appears to be multi-factorial in aetiology and there is no evidence for an increased risk of chronic obstructive pulmonary disease or histological pathology post deployment. At present, there is no definitive evidence of chronic respiratory disease due to exposure to poor AQ while deployed. Further objective longitudinal studies are required to continue to investigate the association, diagnosis and management of those with ongoing symptoms.
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G3BP is the central node within stress-induced protein-RNA interaction networks known as stress granules (SGs). The SG-associated proteins Caprin-1 and USP10 bind mutually exclusively to the NTF2 domain of G3BP1, promoting and inhibiting SG formation, respectively. Herein, we present the crystal structure of G3BP1-NTF2 in complex with a Caprin-1-derived short linear motif (SLiM). Caprin-1 interacts with His-31 and His-62 within a third NTF2-binding site outside those covered by USP10, as confirmed using biochemical and biophysical-binding assays. Nano-differential scanning fluorimetry revealed reduced thermal stability of G3BP1-NTF2 at acidic pH. This destabilization was counterbalanced significantly better by bound USP10 than Caprin-1. The G3BP1/USP10 complex immunoprecipated from human U2OS cells was more resistant to acidic buffer washes than G3BP1/Caprin-1. Acidification of cellular condensates by approximately 0.5 units relative to the cytosol was detected by ratiometric fluorescence analysis of pHluorin2 fused to G3BP1. Cells expressing a Caprin-1/FGDF chimera with higher G3BP1-binding affinity had reduced Caprin-1 levels and slightly reduced condensate sizes. This unexpected finding may suggest that binding of the USP10-derived SLiM to NTF2 reduces the propensity of G3BP1 to enter condensates.
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ADN Helicasas , Gránulos de Estrés , Humanos , Proteínas de Unión a Poli-ADP-Ribosa , ARN Helicasas , Proteínas con Motivos de Reconocimiento de ARN , Concentración de Iones de Hidrógeno , Ubiquitina TiolesterasaRESUMEN
Centrosomes are orbited by centriolar satellites, dynamic multiprotein assemblies nucleated by Pericentriolar material 1 (PCM1). To study the requirement for centriolar satellites, we generated mice lacking PCM1, a crucial component of satellites. Pcm1-/- mice display partially penetrant perinatal lethality with survivors exhibiting hydrocephalus, oligospermia, and cerebellar hypoplasia, and variably expressive phenotypes such as hydronephrosis. As many of these phenotypes have been observed in human ciliopathies and satellites are implicated in cilia biology, we investigated whether cilia were affected. PCM1 was dispensable for ciliogenesis in many cell types, whereas Pcm1-/- multiciliated ependymal cells and human PCM1-/- retinal pigmented epithelial 1 (RPE1) cells showed reduced ciliogenesis. PCM1-/- RPE1 cells displayed reduced docking of the mother centriole to the ciliary vesicle and removal of CP110 and CEP97 from the distal mother centriole, indicating compromised early ciliogenesis. Similarly, Pcm1-/- ependymal cells exhibited reduced removal of CP110 from basal bodies in vivo. We propose that PCM1 and centriolar satellites facilitate efficient trafficking of proteins to and from centrioles, including the departure of CP110 and CEP97 to initiate ciliogenesis, and that the threshold to trigger ciliogenesis differs between cell types.
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Centriolos , Cilios , Animales , Femenino , Humanos , Ratones , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Centriolos/metabolismo , Centrosoma/metabolismo , Cilios/metabolismo , Proteínas del Citoesqueleto/metabolismoRESUMEN
BACKGROUND: In May 2020, first-year students at Imperial College School of Medicine attended a 'digital hospital placement'. Occurring in the early months of the COVID-19 pandemic, this replaced their first planned hospital placement. The authors analysed student experiences to understand how a digital hospital placement impacted self-perceived clinical and professional development and whether it improved preparedness for face-to-face hospital placements. METHODS: Three hundred ten students participated in this week-long digital placement, which integrated clinical skills, communication and professional behaviour domains. It aimed to prepare students for safe participation in clinical environments. Resources included self-directed and peer learning, virtual simulations (Oxford Medical Simulation) and staff-led debriefing. Surveys were administered after the digital placement and after students' first face-to-face placement to collect quantitative and qualitative data. A reflexive thematic analysis was conducted. RESULTS: Eighty-three and twenty-nine students completed the postdigital and post-face-to-face placement evaluation respectively. Quantitative results indicated a high self-rated achievement of learning objectives and enthusiasm for digital placements; 83% of respondents supported digital simulations as part of regular medical education. Qualitative analysis identified three superordinate themes: (1) domain integration in digital placements helped students feel better prepared; (2) digital experiential learning is ideally suited to early clinical learning; and (3) virtual placements are a compliment, not an alternative, to face-to-face placements. CONCLUSION: Digital placements are a promising means of supporting the challenging transition from classroom learner to clinical learner. They provide a feasible and scalable option for building student confidence and improving preparedness.
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COVID-19 , Pandemias , Humanos , COVID-19/epidemiología , Estudiantes , Aprendizaje , ComunicaciónRESUMEN
BACKGROUND: Malaria is a life-threatening disease. Prior to the pandemic, over a million people annually from non-endemic, high income countries such as Europe and North America visited countries with a risk of malaria transmission. Emergency care nurses in non-endemic countries frequently encounter returning travellers, presenting with symptoms suggestive of malaria. While rapid diagnostic tests are used in countries with endemic malaria, in countries such as the United Kingdom diagnosis is undertaken by microscopy and three negative tests are required to exclude. QUESTION: Are rapid diagnostic tests effective for diagnosing imported malaria in non-endemic, high income countries? METHOD: A systematic review of published research (January 2009 - November 2020) comparing rapid diagnostic tests with microscopy. RESULTS: Fourteen studies were included, conducted in five countries with 14 different RDTs evaluated. Mean sensitivity and specificity for Plasmodium Falciparum was 91.8% and 97.7% and Plasmodium Vivax 81.6% and 99.2%. Higher sensitivities were related to higher parasite densities. CONCLUSIONS: International travel will return post-pandemic and rapid, accurate and cost-efficient tests will be required. The rapid diagnostic tests in these studies showed significant variation and were not as accurate as microscopy. Consequently, it cannot be recommended that rapid diagnostic tests replace the gold standard of microscopy. Further research is required.
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Pruebas Diagnósticas de Rutina , Malaria , Países Desarrollados , Humanos , Malaria/diagnóstico , Plasmodium vivax , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Phase III trials have estimated coronavirus disease 2019 (COVID-19) vaccine efficacy (VE) against symptomatic and asymptomatic infection. We explore the direction and magnitude of potential biases in these estimates and their implications for vaccine protection against infection and against disease in breakthrough infections. METHODS: We developed a mathematical model that accounts for natural and vaccine-induced immunity, changes in serostatus, and imperfect sensitivity and specificity of tests for infection and antibodies. We estimated expected biases in VE against symptomatic, asymptomatic, and any severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections and against disease following infection for a range of vaccine characteristics and measurement approaches, and the likely overall biases for published trial results that included asymptomatic infections. RESULTS: VE against asymptomatic infection measured by polymerase chain reaction (PCR) or serology is expected to be low or negative for vaccines that prevent disease but not infection. VE against any infection is overestimated when asymptomatic infections are less likely to be detected than symptomatic infections and the vaccine protects against symptom development. A competing bias toward underestimation arises for estimates based on tests with imperfect specificity, especially when testing is performed frequently. Our model indicates considerable uncertainty in Oxford-AstraZeneca ChAdOx1 and Janssen Ad26.COV2.S VE against any infection, with slightly higher than published, bias-adjusted values of 59.0% (95% uncertainty interval [UI] 38.4-77.1) and 70.9% (95% UI 49.8-80.7), respectively. CONCLUSIONS: Multiple biases are likely to influence COVID-19 VE estimates, potentially explaining the observed difference between ChAdOx1 and Ad26.COV2.S vaccines. These biases should be considered when interpreting both efficacy and effectiveness study results.
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Vacunas contra la COVID-19 , COVID-19 , Ad26COVS1 , Infecciones Asintomáticas , Sesgo , COVID-19/prevención & control , Humanos , SARS-CoV-2 , Eficacia de las VacunasRESUMEN
PURPOSE: This study aimed to measure the prevalence of menopausal symptoms in patients attending a multidisciplinary model of care clinic at their initial clinic visit and their subsequent follow-up consultation using a validated patient-reported outcome measure to assess whether menopausal symptoms after cancer had improved. METHODS: A retrospective review was conducted of patients attending the clinic in a 12-month period in 2017 (n = 189). Recorded variables included patient demographics, details of index cancer, previous treatments, and menopausal symptom management strategies. Severity of menopausal symptoms was evaluated using the Greene Climacteric Scale. The extent to which patients were bothered by symptoms was combined into two categories and dichotomized (present/absent). Differences in symptom prevalence between the initial consultation and first follow-up visit were examined using McNemar's test. RESULTS: The majority of patients attending the clinic had a history of breast cancer (72%). Fifty-five percent of patients were prescribed a non-hormonal therapy at their initial visit, most commonly gabapentin. Significantly fewer patients reported being bothered by hot flushes, fatigue, sleep difficulties, and loss of interest in sex, anxiety, or troubles concentrating at the first follow-up visit compared to their initial consultation (p < 0.01). CONCLUSION: In this study, there was an improvement in self-reported menopausal symptoms in a significant proportion of cancer survivors attending a multidisciplinary menopause clinic between their initial and first subsequent follow-up consultations.
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Neoplasias de la Mama , Supervivientes de Cáncer , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/terapia , Femenino , Sofocos/epidemiología , Sofocos/etiología , Humanos , Menopausia , Estudios RetrospectivosRESUMEN
Stress granules (SGs) are dynamic RNA-protein complexes localized in the cytoplasm that rapidly form under stress conditions and disperse when normal conditions are restored. The formation of SGs depends on the Ras-GAP SH3 domain-binding protein (G3BP). Formations, interactions and functions of plant and human SGs are strikingly similar, suggesting a conserved mechanism. However, functional analyses of plant G3BPs are missing. Thus, members of the Arabidopsis thaliana G3BP (AtG3BP) protein family were investigated in a complementation assay in a human G3BP knock-out cell line. It was shown that two out of seven AtG3BPs were able to complement the function of their human homolog. GFP-AtG3BP fusion proteins co-localized with human SG marker proteins Caprin-1 and eIF4G1 and restored SG formation in G3BP double KO cells. Interaction between AtG3BP-1 and -7 and known human G3BP interaction partners such as Caprin-1 and USP10 was also demonstrated by co-immunoprecipitation. In addition, an RG/RGG domain exchange from Arabidopsis G3BP into the human G3BP background showed the ability for complementation. In summary, our results support a conserved mechanism of SG function over the kingdoms, which will help to further elucidate the biological function of the Arabidopsis G3BP protein family.
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Arabidopsis/metabolismo , Gránulos Citoplasmáticos/metabolismo , Estrés Fisiológico , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Línea Celular Tumoral , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Fenotipo , Filogenia , Unión Proteica , Dominios ProteicosRESUMEN
Identification of the molecular networks that facilitated the evolution of multicellular animals from their unicellular ancestors is a fundamental problem in evolutionary cellular biology. Choanoflagellates are recognized as the closest extant nonmetazoan ancestors to animals. These unicellular eukaryotes can adopt a multicellular-like "rosette" state. Therefore, they are compelling models for the study of early multicellularity. Comparative studies revealed that a number of putative human orthologs are present in choanoflagellate genomes, suggesting that a subset of these genes were necessary for the emergence of multicellularity. However, previous work is largely based on sequence alignments alone, which does not confirm structural nor functional similarity. Here, we focus on the PDZ domain, a peptide-binding domain which plays critical roles in myriad cellular signaling networks and which underwent a gene family expansion in metazoan lineages. Using a customized sequence similarity search algorithm, we identified 178 PDZ domains in the Monosiga brevicollis proteome. This includes 11 previously unidentified sequences, which we analyzed using Rosetta and homology modeling. To assess conservation of protein structure, we solved high-resolution crystal structures of representative M. brevicollis PDZ domains that are homologous to human Dlg1 PDZ2, Dlg1 PDZ3, GIPC, and SHANK1 PDZ domains. To assess functional conservation, we calculated binding affinities for mbGIPC, mbSHANK1, mbSNX27, and mbDLG-3 PDZ domains from M. brevicollis. Overall, we find that peptide selectivity is generally conserved between these two disparate organisms, with one possible exception, mbDLG-3. Overall, our results provide novel insight into signaling pathways in a choanoflagellate model of primitive multicellularity.
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Algoritmos , Coanoflagelados/química , Modelos Moleculares , Dominios PDZ , Proteínas Protozoarias/química , Análisis de Secuencia de Proteína , Coanoflagelados/genética , Cristalografía por Rayos X , Bases de Datos de Proteínas , Proteínas Protozoarias/genéticaRESUMEN
OBJECTIVE: Animal studies remain essential for understanding mechanisms of epilepsy and identifying new therapeutic targets. However, existing animal models of epilepsy do not reflect the high level of genetic diversity found in the human population. The Collaborative Cross (CC) population is a genetically diverse recombinant inbred panel of mice. The CC offers large genotypic and phenotypic diversity, inbred strains with stable genomes that allow for repeated phenotypic measurements, and genomic tools including whole genome sequence to identify candidate genes and candidate variants. METHODS: We evaluated multiple complex epileptic traits in a sampling of 35 CC inbred strains using the flurothyl-induced seizure and kindling paradigm. We created an F2 population of 297 mice with extreme seizure susceptibility and performed quantitative trait loci (QTL) mapping to identify genomic regions associated with seizure sensitivity. We used quantitative RNA sequencing from CC hippocampal tissue to identify candidate genes and whole genome sequence to identify genetic variants likely affecting gene expression. RESULTS: We identified new mouse models with extreme seizure susceptibility, seizure propagation, epileptogenesis, and SUDEP (sudden unexpected death in epilepsy). We performed QTL mapping and identified one known and seven novel loci associated with seizure sensitivity. We combined whole genome sequencing and hippocampal gene expression to pinpoint biologically plausible candidate genes (eg, Gabra2) and variants associated with seizure sensitivity. SIGNIFICANCE: New mouse models of epilepsy are needed to better understand the complex genetic architecture of seizures and to identify therapeutics. We performed a phenotypic screen utilizing a novel genetic reference population of CC mice. The data we provide enable the identification of protective/risk genes and novel molecular mechanisms linked to complex seizure traits that are currently challenging to study and treat.
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Ratones de Colaboración Cruzada/genética , Modelos Animales de Enfermedad , Epilepsia/genética , Hipocampo/metabolismo , Ratones , Convulsiones/genética , Animales , Mapeo Cromosómico , Convulsivantes , Epilepsia/inducido químicamente , Epilepsia/metabolismo , Epilepsia/fisiopatología , Agonistas de Aminoácidos Excitadores , Flurotilo , Expresión Génica , Perfilación de la Expresión Génica , Predisposición Genética a la Enfermedad , Genotipo , Ácido Kaínico , Ratones Endogámicos , Pentilenotetrazol , Fenotipo , Sitios de Carácter Cuantitativo , Convulsiones/inducido químicamente , Convulsiones/metabolismo , Convulsiones/fisiopatología , Muerte Súbita e Inesperada en la Epilepsia , Secuenciación Completa del GenomaRESUMEN
The pre-Columbian Huecoid and Saladoid cultures were agricultural ethnic groups that supplemented their diets by fishing, hunting and scavenging. Archaeological deposits associated to these cultures contained a variety of faunal osseous remains that hinted at the cultures' diets. The present study identified zoonotic parasites that may have infected these two cultures as a result of their diets. We used metagenomic sequencing and microscopy data from 540-1,400 year old coprolites as well as the zooarchaeological data to recreate the possible interactions between zoonotic parasites and their hosts. Microscopy revealed Diphyllobothrium spp. and Dipylidium caninum eggs along with unidentified cestode and trematode eggs. DNA sequencing together with functional prediction and phylogenetic inference identified reads of Cryptosporidium spp., Giardia intestinalis and Schistosoma spp. The complimentary nature of the molecular, microscopy and zooarchaeology data provided additional insight into the detected zoonotic parasites' potential host range. Network modeling revealed that rodents and canids living in close proximity to these cultures were most likely the main source of these zoonotic parasite infections.
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Parásitos/aislamiento & purificación , Zoonosis/historia , Animales , Dieta/efectos adversos , Historia del Siglo XV , Historia Medieval , Interacciones Huésped-Parásitos , Humanos , Estilo de Vida , Metagenómica , Parásitos/genética , Parásitos/fisiología , Puerto Rico/epidemiología , Análisis de Secuencia de ADN , Zoonosis/epidemiología , Zoonosis/parasitologíaRESUMEN
Biomass catalytic pyrolysis with various metals (Zn, Fe, Ca, Ce and La) modified ZSM-5 catalysts were analyzed, in order to investigate the relationship between the physicochemical properties of catalysts and the benzene, toluene and xylene (BTX) products. Results revealed that the BTX products were positively correlated with the strong acid site contents of the catalysts. Appropriate amount (0.5-4â¯wt%) of loaded Zn species increased the strong acid site contents of the catalysts as well as BTX yields, and the highest yield of BTX was observed under Zn loading amount of 2â¯wt%. While excessive metal loading amount (10â¯wt%) decreased both the acidity and the physical properties of the catalyst, resulting in poor diffusion of reactants and products in the channel and decreased the BTX yield. It is recommended that ZSM-5 catalyst with higher strong acid site content and pore volume should be used for BTX production.
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Benceno/química , Tolueno/química , Xilenos/química , Zeolitas/química , Biomasa , Calcio/química , Catálisis , Fenómenos Químicos , Lantano/química , Metales Pesados/química , PirólisisRESUMEN
Regulation by gene-distal enhancers is critical for cell type-specific and condition-specific patterns of gene expression. Thus, to understand the basis of gene activity in a given cell type or tissue, we must identify the precise locations of enhancers and functionally characterize their behaviors. Here, we demonstrate that transcription is a nearly universal feature of enhancers in Drosophila and mammalian cells and that nascent RNA sequencing strategies are optimal for identification of both enhancers and superenhancers. We dissect the mechanisms governing enhancer transcription and discover remarkable similarities to transcription at protein-coding genes. We show that RNA polymerase II (RNAPII) undergoes regulated pausing and release at enhancers. However, as compared with mRNA genes, RNAPII at enhancers is less stable and more prone to early termination. Furthermore, we found that the level of histone H3 Lys4 (H3K4) methylation at enhancers corresponds to transcriptional activity such that highly active enhancers display H3K4 trimethylation rather than the H3K4 monomethylation considered a hallmark of enhancers. Finally, our work provides insights into the unique characteristics of superenhancers, which stimulate high-level gene expression through rapid pause release; interestingly, this property renders associated genes resistant to the loss of factors that stabilize paused RNAPII.
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Elementos de Facilitación Genéticos , Regulación de la Expresión Génica , Elongación de la Transcripción Genética , Animales , Cromatina/química , Proteínas Cromosómicas no Histona/fisiología , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/biosíntesis , Proteínas de Drosophila/fisiología , Células Madre Embrionarias/metabolismo , Histonas/metabolismo , Ratones , Regiones Promotoras Genéticas , ARN Polimerasa II/metabolismo , ARN no Traducido/biosíntesis , Sitio de Iniciación de la Transcripción , Transcripción Genética , Factores de Elongación Transcripcional/fisiologíaRESUMEN
The Collaborative Cross (CC) is a multiparent panel of recombinant inbred (RI) mouse strains derived from eight founder laboratory strains. RI panels are popular because of their long-term genetic stability, which enhances reproducibility and integration of data collected across time and conditions. Characterization of their genomes can be a community effort, reducing the burden on individual users. Here we present the genomes of the CC strains using two complementary approaches as a resource to improve power and interpretation of genetic experiments. Our study also provides a cautionary tale regarding the limitations imposed by such basic biological processes as mutation and selection. A distinct advantage of inbred panels is that genotyping only needs to be performed on the panel, not on each individual mouse. The initial CC genome data were haplotype reconstructions based on dense genotyping of the most recent common ancestors (MRCAs) of each strain followed by imputation from the genome sequence of the corresponding founder inbred strain. The MRCA resource captured segregating regions in strains that were not fully inbred, but it had limited resolution in the transition regions between founder haplotypes, and there was uncertainty about founder assignment in regions of limited diversity. Here we report the whole genome sequence of 69 CC strains generated by paired-end short reads at 30× coverage of a single male per strain. Sequencing leads to a substantial improvement in the fine structure and completeness of the genomes of the CC. Both MRCAs and sequenced samples show a significant reduction in the genome-wide haplotype frequencies from two wild-derived strains, CAST/EiJ and PWK/PhJ. In addition, analysis of the evolution of the patterns of heterozygosity indicates that selection against three wild-derived founder strains played a significant role in shaping the genomes of the CC. The sequencing resource provides the first description of tens of thousands of new genetic variants introduced by mutation and drift in the CC genomes. We estimate that new SNP mutations are accumulating in each CC strain at a rate of 2.4 ± 0.4 per gigabase per generation. The fixation of new mutations by genetic drift has introduced thousands of new variants into the CC strains. The majority of these mutations are novel compared to currently sequenced laboratory stocks and wild mice, and some are predicted to alter gene function. Approximately one-third of the CC inbred strains have acquired large deletions (>10 kb) many of which overlap known coding genes and functional elements. The sequence of these mice is a critical resource to CC users, increases threefold the number of mouse inbred strain genomes available publicly, and provides insight into the effect of mutation and drift on common resources.
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Flujo Genético , Genoma/genética , Ratones Endogámicos/genética , Sitios de Carácter Cuantitativo/genética , Animales , Mapeo Cromosómico , Cruzamientos Genéticos , Genotipo , Haplotipos , Masculino , Ratones , Mutación , Polimorfismo de Nucleótido SimpleRESUMEN
Here, we present a somewhat unusual suicide attempt where, despite an unbelievable overdose with transdermal fentanyl patches, the patient survived. The patient-a woman aged 70 years, who has suffered from chronic back pain despite starting transdermal fentanyl patches in 2007. The unconventional method of attempted suicide was based on online research into deaths from fentanyl patch toxicity. She had gradually accumulated 100â µg fentanyl patches from repeat prescriptions, applying 14 patches with fatal intent, alongside 2 45â mg mirtazapine tablets, and concurrent therapeutic doses of tramadol and morphine sulfate oral solution. However, after 24â hours, she awoke from a deep sleep to the sound of the telephone ringing, somewhat amazed her drastic efforts had failed. During admission to Great Western hospital, she was seen by liaison psychiatry and subsequently transferred to the care of the pain management team, to which she had already been referred.