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1.
Nature ; 563(7729): 40-42, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30375500
2.
Plant Physiol ; 170(3): 1655-74, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26813793

RESUMEN

Leaves are derived from heterotrophic meristem tissue that, at some point, must make the transition to autotrophy via the initiation of photosynthesis. However, the timing and spatial coordination of the molecular and cellular processes underpinning this switch are poorly characterized. Here, we report on the identification of a specific stage in rice (Oryza sativa) leaf development (P3/P4 transition) when photosynthetic competence is first established. Using a combined physiological and molecular approach, we show that elements of stomatal and vascular differentiation are coordinated with the onset of measurable light absorption for photosynthesis. Moreover, by exploring the response of the system to environmental perturbation, we show that the earliest stages of rice leaf development have significant plasticity with respect to elements of cellular differentiation of relevance for mature leaf photosynthetic performance. Finally, by performing an RNA sequencing analysis targeted at the early stages of rice leaf development, we uncover a palette of genes whose expression likely underpins the acquisition of photosynthetic capability. Our results identify the P3/P4 transition as a highly dynamic stage in rice leaf development when several processes for the initiation of photosynthetic competence are coordinated. As well as identifying gene targets for future manipulation of rice leaf structure/function, our data highlight a developmental window during which such manipulations are likely to be most effective.


Asunto(s)
Clorofila/metabolismo , Perfilación de la Expresión Génica/métodos , Oryza/genética , Fotosíntesis/genética , Hojas de la Planta/genética , Clorofila/química , Fluorescencia , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Luz , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Oryza/crecimiento & desarrollo , Oryza/metabolismo , Fotosíntesis/efectos de la radiación , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Estomas de Plantas/genética , Estomas de Plantas/metabolismo , Estomas de Plantas/ultraestructura , Haz Vascular de Plantas/genética , Haz Vascular de Plantas/crecimiento & desarrollo , Haz Vascular de Plantas/metabolismo , Plastidios/genética , Plastidios/metabolismo , Plastidios/ultraestructura , Factores de Tiempo
3.
BMC Evol Biol ; 15: 116, 2015 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-26084484

RESUMEN

BACKGROUND: The genus Flaveria has been extensively used as a model to study the evolution of C4 photosynthesis as it contains C3 and C4 species as well as a number of species that exhibit intermediate types of photosynthesis. The current phylogenetic tree of the genus Flaveria contains 21 of the 23 known Flaveria species and has been previously constructed using a combination of morphological data and three non-coding DNA sequences (nuclear encoded ETS, ITS and chloroplast encoded trnL-F). RESULTS: Here we developed a new strategy to update the phylogenetic tree of 16 Flaveria species based on RNA-Seq data. The updated phylogeny is largely congruent with the previously published tree but with some modifications. We propose that the data collection method provided in this study can be used as a generic method for phylogenetic tree reconstruction if the target species has no genomic information. We also showed that a "F. pringlei" genotype recently used in a number of labs may be a hybrid between F. pringlei (C3) and F. angustifolia (C3-C4). CONCLUSIONS: We propose that the new strategy of obtaining phylogenetic sequences outlined in this study can be used to construct robust trees in a larger number of taxa. The updated Flaveria phylogenetic tree also supports a hypothesis of stepwise and parallel evolution of C4 photosynthesis in the Flavaria clade.


Asunto(s)
Flaveria/clasificación , Flaveria/genética , Filogenia , Secuencia de Aminoácidos , Evolución Biológica , Cloroplastos/genética , Flaveria/fisiología , Fotosíntesis , ARN de Planta/análisis , Análisis de Secuencia de ARN/métodos
4.
Acta Psychol (Amst) ; 243: 104125, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38245938

RESUMEN

To our knowledge, no study has directly examined the link between hypnotic response and the personality trait of transliminality (which is underpinned, for example, by magical ideation, mystical experience, fantasy proneness, absorption, hyperaesthesia). In order to further understand the correlates of suggestibility, the aim of the current project was to investigate whether transliminality is associated with hypnotic and imaginative suggestibility (considering: objective response, subjective response and involuntariness). Another aim was to assess the contribution of transliminality as a predictor of suggestibility when a range of previously studied personality trait measures were considered. Participants completed: the Revised Transliminality Scale, Tellegen Absorption Scale, Creative Experiences Questionnaire, and the Dissociative Experiences Scale II. To avoid context effects, where knowledge or measurement of one trait or ability might influence measurement of another, a separate standalone study was conducted where hypnotic and imaginative (without hypnosis) suggestibility screenings were carried out in-person in small groups using the modified Carleton University Responsiveness to Suggestion Scale. The merging of these two datasets enabled the analyses. Transliminality was weakly correlated with the imaginative suggestibility subjective response measure (r = 0.19). Likewise, weak correlations were found between transliminality and the hypnotic suggestibility response measures (objective, r = 0.21, subjective, r = 0.23, involuntariness, r = 0.24). The multiple regressions (forward selection) reflected the pattern of correlations, with no model for any of the variables, retaining more than a single significant predictor. In summary, this study combination, avoiding context effects, shows transliminality to be a weak predictor of response to suggestion.


Asunto(s)
Hipnosis , Imaginación , Humanos , Sugestión , Fantasía , Personalidad
5.
Sci Rep ; 14(1): 4936, 2024 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-38472289

RESUMEN

Many countries with tropical reef systems face hard choices preserving coral reefs in the face of climate change on limited budgets. One approach to maximising regional reef resilience is targeting management efforts and resources at reefs that export large numbers of larvae to other reefs. However, this requires reef connectivity to be quantified. To map coral connectivity in the Seychelles reef system we carried out a population genomic study of the Porites lutea species complex using 241 sequenced colonies from multiple islands. To identify oceanographic drivers of this connectivity and quantify variability, we further used a 2 km resolution regional ocean simulation coupled with a larval dispersal model to predict the flow of coral larvae between reef sites. Patterns of admixture and gene flow are broadly supported by model predictions, but the realised connectivity is greater than that predicted from model simulations. Both methods detected a biogeographic dispersal barrier between the Inner and Outer Islands of Seychelles. However, this barrier is permeable and substantial larval transport is possible across Seychelles, particularly for one of two putative species found in our genomic study. The broad agreement between predicted connectivity and observed genetic patterns supports the use of such larval dispersal simulations in reef system management in Seychelles and the wider region.


Asunto(s)
Antozoos , Arrecifes de Coral , Animales , Seychelles , Antozoos/genética , Genética de Población , Larva
6.
Antimicrob Agents Chemother ; 57(7): 3182-93, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23629718

RESUMEN

Antifungal resistance of Candida species is a clinical problem in the management of diseases caused by these pathogens. In this study we identified from a collection of 423 clinical samples taken from Tunisian hospitals two clinical Candida species (Candida albicans JEY355 and Candida tropicalis JEY162) with decreased susceptibility to azoles and polyenes. For JEY355, the fluconazole (FLC) MIC was 8 µg/ml. Azole resistance in C. albicans JEY355 was mainly caused by overexpression of a multidrug efflux pump of the major facilitator superfamily, Mdr1. The regulator of Mdr1, MRR1, contained a yet-unknown gain-of-function mutation (V877F) causing MDR1 overexpression. The C. tropicalis JEY162 isolate demonstrated cross-resistance between FLC (MIC > 128 µg/ml), voriconazole (MIC > 16 µg/ml), and amphotericin B (MIC > 32 µg/ml). Sterol analysis using gas chromatography-mass spectrometry revealed that ergosterol was undetectable in JEY162 and that it accumulated 14α-methyl fecosterol, thus indicating a perturbation in the function of at least two main ergosterol biosynthesis proteins (Erg11 and Erg3). Sequence analyses of C. tropicalis ERG11 (CtERG11) and CtERG3 from JEY162 revealed a deletion of 132 nucleotides and a single amino acid substitution (S258F), respectively. These two alleles were demonstrated to be nonfunctional and thus are consistent with previous studies showing that ERG11 mutants can only survive in combination with other ERG3 mutations. CtERG3 and CtERG11 wild-type alleles were replaced by the defective genes in a wild-type C. tropicalis strain, resulting in a drug resistance phenotype identical to that of JEY162. This genetic evidence demonstrated that CtERG3 and CtERG11 mutations participated in drug resistance. During reconstitution of the drug resistance in C. tropicalis, a strain was obtained harboring only defective Cterg11 allele and containing as a major sterol the toxic metabolite 14α-methyl-ergosta-8,24(28)-dien-3α,6ß-diol, suggesting that ERG3 was still functional. This strain therefore challenged the current belief that ERG11 mutations cannot be viable unless accompanied by compensatory mutations. In conclusion, this study, in addition to identifying a novel MRR1 mutation in C. albicans, constitutes the first report on a clinical C. tropicalis with defective activity of sterol 14α-demethylase and sterol Δ(5,6)-desaturase leading to azole-polyene cross-resistance.


Asunto(s)
Candida albicans/efectos de los fármacos , Candida glabrata/efectos de los fármacos , Candida tropicalis/efectos de los fármacos , Sistema Enzimático del Citocromo P-450/genética , Farmacorresistencia Fúngica/genética , Proteínas Fúngicas/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Anfotericina B/farmacología , Antifúngicos/farmacología , Azoles/farmacología , Secuencia de Bases , Candida albicans/genética , Candida albicans/aislamiento & purificación , Candida glabrata/genética , Candida glabrata/aislamiento & purificación , Candida tropicalis/aislamiento & purificación , Candidiasis/tratamiento farmacológico , Sistema Enzimático del Citocromo P-450/metabolismo , Ergosterol/biosíntesis , Ergosterol/genética , Fluconazol/farmacología , Proteínas Fúngicas/metabolismo , Humanos , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Mutación , Polienos/farmacología , Pirimidinas/farmacología , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Análisis de Secuencia de ADN , Triazoles/farmacología , Túnez , Voriconazol
7.
Breast Cancer Res Treat ; 133(3): 1057-65, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22418700

RESUMEN

Afatinib is an oral, ErbB family blocker, which covalently binds and irreversibly blocks all kinase-competent ErbB family members. This phase II, open-label, single-arm study explored afatinib activity in human epidermal growth factor receptor 2 (HER2)-positive breast cancer patients progressing after trastuzumab treatment. Patients had stage IIIB/IV HER2-positive metastatic breast cancer, with progression following trastuzumab or trastuzumab intolerance and an Eastern Cooperative Oncology Group (ECOG) performance status of 0-2. Patients received 50 mg afatinib once-daily until disease progression. Primary endpoint was objective response rate (Response Evaluation Criteria in Solid Tumors 1.0), with tumor assessments every 8 weeks. Forty-one patients were treated. Patients had received a median of three prior chemotherapy lines (range, 0-15) and 68.3% had received trastuzumab for >1 year. Four patients (10% of 41 treated; 11% of evaluable patients) had partial response. Fifteen patients (37% of 41) had stable disease as best response and 19 (46% of 41) achieved clinical benefit. Median progression-free survival was 15.1 weeks (95% confidence interval [CI]: 8.1-16.7); median overall survival was 61.0 weeks (95% CI: 56.7-not evaluable). Most frequent common terminology criteria for adverse events grade 3 treatment-related adverse events were diarrhea (24.4%) and rash (9.8%). Afatinib monotherapy was associated with promising clinical activity in extensively pretreated HER2-positive breast cancer patients who had progressed following trastuzumab treatment.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Quinazolinas/uso terapéutico , Receptor ErbB-2/antagonistas & inhibidores , Adulto , Afatinib , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales Humanizados/uso terapéutico , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Progresión de la Enfermedad , Femenino , Humanos , Persona de Mediana Edad , Metástasis de la Neoplasia , Quinazolinas/administración & dosificación , Quinazolinas/efectos adversos , Receptor ErbB-2/metabolismo , Trastuzumab , Resultado del Tratamiento
8.
Clin Microbiol Infect ; 28(6): 838-843, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34915074

RESUMEN

OBJECTIVE: Candida auris has emerged as a health-care-associated and multidrug-resistant fungal pathogen of great clinical concern. As many as 50% of C. auris clinical isolates are reported to be resistant to amphotericin B, but no mechanisms contributing to this resistance have been identified. Here we describe a clinical case in which high-level amphotericin B resistance was acquired in vivo during therapy and undertake molecular and genetic studies to identify and characterize the genetic determinant of resistance. METHODS: Whole-genome sequencing was performed on four C. auris isolates obtained from a single patient case. Cas9-mediated genetic manipulations were then used to generate mutant strains harbouring mutations of interest, and these strains were subsequently subjected to amphotericin B susceptibility testing and comprehensive sterol profiling. RESULTS: A novel mutation in the C. auris sterol-methyltransferase gene ERG6 was found to be associated with amphotericin B resistance, and this mutation alone conferred a >32-fold increase in amphotericin B resistance. Comprehensive sterol profiling revealed an abrogation of ergosterol biosynthesis and a corresponding accumulation of cholesta-type sterols in isolates and strains harbouring the clinically derived ERG6 mutation. CONCLUSIONS: Together these findings definitively demonstrate mutations in C. auris ERG6 as the first identified mechanism of clinical amphotericin B resistance in C. auris and represent a significant step forward in the understanding of antifungal resistance in this emerging public health threat.


Asunto(s)
Anfotericina B , Candida auris , Anfotericina B/farmacología , Anfotericina B/uso terapéutico , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Humanos , Pruebas de Sensibilidad Microbiana , Esteroles
9.
Mol Biochem Parasitol ; 241: 111348, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33352254

RESUMEN

The bloodstream form of Trypanosoma brucei persists in mammalian hosts through a population survival strategy depending on antigenic variation of a cell surface coat composed of the variant surface glycoprotein (VSG). The integrity of the VSG coat is essential and blocking its synthesis results in a cell division cycle arrest just prior to cytokinesis. This observation indicates that VSG levels are monitored and that the cell has mechanisms to respond to a disruption of synthesis. Here, the regulation of VSG mRNA levels has been investigated by first measuring VSG mRNA copy number, and second using ectopic expression of VSG transgenes containing premature termination codons. The findings are that (i) VSG mRNA copy number varies with the identity of the VSG and (ii) a pathway detects synthesis of non-functional VSG protein and results in an increase in VSG mRNA levels.


Asunto(s)
Regulación de la Expresión Génica , Trypanosoma brucei brucei/fisiología , Tripanosomiasis Africana/parasitología , Glicoproteínas Variantes de Superficie de Trypanosoma/genética , Línea Celular , Interacciones Huésped-Parásitos , ARN Mensajero/genética , Tripanosomiasis Africana/metabolismo , Glicoproteínas Variantes de Superficie de Trypanosoma/metabolismo
10.
Sci Rep ; 11(1): 15618, 2021 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-34341365

RESUMEN

C4 photosynthesis is a remarkable complex trait, elucidations of the evolutionary trajectory of C4 photosynthesis from its ancestral C3 pathway can help us better understand the generic principles of the evolution of complex traits and guide the engineering of C3 crops for higher yields. Here, we used the genus Flaveria that contains C3, C3-C4, C4-like and C4 species as a system to study the evolution of C4 photosynthesis. We first mapped transcript abundance, protein sequence and morphological features onto the phylogenetic tree of the genus Flaveria, and calculated the evolutionary correlation of different features; we then predicted the relative changes of ancestral nodes of those features to illustrate the major events during the evolution of C4 photosynthesis. We found that gene expression and protein sequence showed consistent modification patterns in the phylogenetic tree. High correlation coefficients ranging from 0.46 to 0.9 among gene expression, protein sequence and morphology were observed. The greatest modification of those different features consistently occurred at the transition between C3-C4 species and C4-like species. Our results show highly coordinated changes in gene expression, protein sequence and morphological features, which support evolutionary major events during the evolution of C4 metabolism.


Asunto(s)
Flaveria , Fotosíntesis , Filogenia , Evolución Biológica , Cloroplastos/metabolismo
11.
Prim Care Respir J ; 19(1): 68-74, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20094687

RESUMEN

AIMS: This study presents a cost-effectiveness and budget impact analysis comparing cost and outcomes for UK patients with COPD treated with either tiotropium, ipratropium or salmeterol. METHODS: A previously-published COPD cost-effectiveness model was adapted for the UK, then used to estimate the cost-effectiveness of tiotropium compared to salmeterol and ipratropium. Additional epidemiological data were used to estimate the budget impact of switching patients from ipratropium or salmeterol to tiotropium. RESULTS: In England, the estimated annual cost per patient on tiotropium was pound1350, on salmeterol was pound1404, and on ipratropium was pound1427; in Scotland/Wales/Northern Ireland (S/W/NI) these costs were pound1439, pound1565, and pound1631, respectively. Tiotropium patients experienced better quality-adjusted life-years (QALYs) across all comparisons, and this option was therefore dominant compared to salmeterol and ipratropium. The probability of tiotropium being dominant ranged from 72% to 87% across comparisons. At a willingness to pay threshold of pound20,000 per QALY, tiotropium had at least a 97% chance of being cost-effective. The estimated annual saving per primary care trust (PCT) of switching patients from salmeterol and ipratropium to tiotropium in England was pound230,000 and in S/W/NI was pound160,000. CONCLUSIONS: Tiotropium is a cost-effective alternative to ipratropium and salmeterol, and switching COPD patients from ipratropium and salmeterol to tiotropium could result in considerable cost savings for PCTs along with improvements in quality-of-life.


Asunto(s)
Albuterol/análogos & derivados , Broncodilatadores/economía , Ipratropio/economía , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Enfermedad Pulmonar Obstructiva Crónica/economía , Derivados de Escopolamina/economía , Albuterol/administración & dosificación , Albuterol/economía , Broncodilatadores/administración & dosificación , Análisis Costo-Beneficio , Humanos , Ipratropio/administración & dosificación , Modelos Econométricos , Análisis Multivariante , Nebulizadores y Vaporizadores , Años de Vida Ajustados por Calidad de Vida , Xinafoato de Salmeterol , Derivados de Escopolamina/administración & dosificación , Índice de Severidad de la Enfermedad , Bromuro de Tiotropio , Resultado del Tratamiento , Reino Unido
12.
Br J Dev Psychol ; 28(Pt 1): 133-76, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20306629

RESUMEN

Research studies have implicated executive functions in reading difficulties (RD). But while some studies have found children with RD to be impaired on tasks of executive function other studies report unimpaired performance. A meta-analysis was carried out to determine whether these discrepant findings can be accounted for by differences in the tasks of executive function that are utilized. A total of 48 studies comparing the performance on tasks of executive function of children with RD with their typically developing peers were included in the meta-analysis, yielding 180 effect sizes. An overall effect size of 0.57 (SE .03) was obtained, indicating that children with RD have impairments on tasks of executive function. However, effect sizes varied considerably suggesting that the impairment is not uniform. Moderator analysis revealed that task modality and IQ-achievement discrepancy definitions of RD influenced the magnitude of effect; however, the age and gender of participants and the nature of the RD did not have an influence. While the children's RD were associated with executive function impairments, variation in effect size is a product of the assessment task employed, underlying task demands, and definitional criteria.


Asunto(s)
Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/epidemiología , Dislexia/epidemiología , Función Ejecutiva , Análisis y Desempeño de Tareas , Adolescente , Distribución por Edad , Niño , Trastornos del Conocimiento/psicología , Comorbilidad , Discriminación en Psicología , Dislexia/psicología , Femenino , Humanos , Inteligencia , Pruebas de Inteligencia/estadística & datos numéricos , Masculino , Lectura , Distribución por Sexo
13.
mBio ; 11(3)2020 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-32398311

RESUMEN

Candida auris has emerged as a multidrug-resistant pathogen of great clinical concern. Approximately 90% of clinical C. auris isolates are resistant to fluconazole, the most commonly prescribed antifungal agent, and yet it remains unknown what mechanisms underpin this fluconazole resistance. To identify novel mechanisms contributing to fluconazole resistance in C. auris, fluconazole-susceptible C. auris clinical isolate AR0387 was passaged in media supplemented with fluconazole to generate derivative strains which had acquired increased fluconazole resistance in vitro Comparative analyses of comprehensive sterol profiles, [3H]fluconazole uptake, sequencing of C. auris genes homologous to genes known to contribute to fluconazole resistance in other species of Candida, and relative expression levels of C. aurisERG11, CDR1, and MDR1 were performed. All fluconazole-evolved derivative strains were found to have acquired mutations in the zinc-cluster transcription factor-encoding gene TAC1B and to show a corresponding increase in CDR1 expression relative to the parental clinical isolate, AR0387. Mutations in TAC1B were also identified in a set of 304 globally distributed C. auris clinical isolates representing each of the four major clades. Introduction of the most common mutation found among fluconazole-resistant clinical isolates of C. auris into fluconazole-susceptible isolate AR0387 was confirmed to increase fluconazole resistance by 8-fold, and the correction of the same mutation in a fluconazole-resistant isolate, AR0390, decreased fluconazole MIC by 16-fold. Taken together, these data demonstrate that C. auris can rapidly acquire resistance to fluconazole in vitro and that mutations in TAC1B significantly contribute to clinical fluconazole resistance.IMPORTANCECandida auris is an emerging multidrug-resistant pathogen of global concern, known to be responsible for outbreaks on six continents and to be commonly resistant to antifungals. While the vast majority of clinical C. auris isolates are highly resistant to fluconazole, an essential part of the available antifungal arsenal, very little is known about the mechanisms contributing to resistance. In this work, we show that mutations in the transcription factor TAC1B significantly contribute to clinical fluconazole resistance. These studies demonstrated that mutations in TAC1B can arise rapidly in vitro upon exposure to fluconazole and that a multitude of resistance-associated TAC1B mutations are present among the majority of fluconazole-resistant C. auris isolates from a global collection and appear specific to a subset of lineages or clades. Thus, identification of this novel genetic determinant of resistance significantly adds to the understanding of clinical antifungal resistance in C. auris.


Asunto(s)
Antifúngicos/farmacología , Candida/efectos de los fármacos , Candida/genética , Farmacorresistencia Fúngica/genética , Fluconazol/farmacología , Proteínas Fúngicas/genética , Pruebas de Sensibilidad Microbiana , Mutación , Factores de Transcripción/genética
14.
Nat Commun ; 11(1): 427, 2020 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-31969561

RESUMEN

The frequency of antifungal resistance, particularly to the azole class of ergosterol biosynthetic inhibitors, is a growing global health problem. Survival rates for those infected with resistant isolates are exceptionally low. Beyond modification of the drug target, our understanding of the molecular basis of azole resistance in the fungal pathogen Aspergillus fumigatus is limited. We reasoned that clinically relevant antifungal resistance could derive from transcriptional rewiring, promoting drug resistance without concomitant reductions in pathogenicity. Here we report a genome-wide annotation of transcriptional regulators in A. fumigatus and construction of a library of 484 transcription factor null mutants. We identify 12 regulators that have a demonstrable role in itraconazole susceptibility and show that loss of the negative cofactor 2 complex leads to resistance, not only to the azoles but also the salvage therapeutics amphotericin B and terbinafine without significantly affecting pathogenicity.


Asunto(s)
Antifúngicos/farmacología , Aspergillus fumigatus/efectos de los fármacos , Farmacorresistencia Fúngica , Proteínas Fúngicas/metabolismo , Anfotericina B/farmacología , Aspergillus fumigatus/genética , Aspergillus fumigatus/metabolismo , Azoles/farmacología , Proteínas Fúngicas/genética , Pruebas de Sensibilidad Microbiana
15.
Disabil Rehabil Assist Technol ; 14(2): 146-160, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-29240522

RESUMEN

PURPOSE: The objective of this research is to identify stakeholder views with regard to the development of effective powered wheelchair assistive technologies more suited to the user and carer needs, whilst also meeting the requirements for other stakeholders, such that developers can be better guided towards producing solutions which have a better chance of getting to the market place and hence to the end user. METHOD: A questionnaire was designed to collect the views of all stakeholders and circulated to a statistically representative number of them. The question rating data were then checked for correlation between groups, and within groups, to establish validity. RESULTS: The 74 stakeholders across the eight classes who responded had a good correlation between each other, with a cross class "Pearson's correlation" ranging between 0.7 and 0.95, and the "Fleiss's Kappa reliability of agreement" within each class ranging between 0.07 and 0.36. CONCLUSIONS: This research has identified that all stakeholders should be involved in the development of the technology and that some may benefit in 'role-reversal' to help understand user problems and stakeholder concerns more clearly. Cost was a significant barrier to the uptake of appropriate technology, and training of users and carers was a major issue. Furthermore, development should not increase user isolation and the impact on the user must be monitored for 'quality of life'. Technical support and training should be given to the user and their carers, and equipment must be adaptive to meet the changing needs of the user. Implications for Rehabilitation Improved acceptance and use of technology by the user and their carers. Reduced rejection of appropriate provision. Improved mobility and interaction with others. Improved quality of life for users and carers.


Asunto(s)
Actitud del Personal de Salud , Personas con Discapacidad/psicología , Evaluación de Necesidades , Silla de Ruedas , Adulto , Suministros de Energía Eléctrica , Diseño de Equipo , Femenino , Humanos , Masculino , Encuestas y Cuestionarios , Reino Unido
16.
mBio ; 10(6)2019 12 24.
Artículo en Inglés | MEDLINE | ID: mdl-31874914

RESUMEN

Multidrug resistance (MDR) has emerged in hospitals due to the use of several agents administered in combination or sequentially to the same individual. We reported earlier MDR in Candida lusitaniae during therapy with amphotericin B (AmB), azoles, and candins. Here, we used comparative genomic approaches between the initial susceptible isolate and 4 other isolates with different MDR profiles. From a total of 18 nonsynonymous single nucleotide polymorphisms (NSS) in genome comparisons with the initial isolate, six could be associated with MDR. One of the single nucleotide polymorphisms (SNPs) occurred in a putative transcriptional activator (MRR1) resulting in a V668G substitution in isolates resistant to azoles and 5-fluorocytosine (5-FC). We demonstrated by genome editing that MRR1 acted by upregulation of MFS7 (a multidrug transporter) in the presence of the V668G substitution. MFS7 itself mediated not only azole resistance but also 5-FC resistance, which represents a novel resistance mechanism for this drug class. Three other distinct NSS occurred in FKS1 (a glucan synthase gene that is targeted by candins) in three candin-resistant isolates. Last, two other NSS in ERG3 and ERG4 (ergosterol biosynthesis) resulting in nonsense mutations were revealed in AmB-resistant isolates, one of which accumulated the two ERG NSS. AmB-resistant isolates lacked ergosterol and exhibited sterol profiles, consistent with ERG3 and ERG4 defects. In conclusion, this genome analysis combined with genetics and metabolomics helped decipher the resistance profiles identified in this clinical case. MDR isolates accumulated six different mutations conferring resistance to all antifungal agents used in medicine. This case study illustrates the capacity of C. lusitaniae to rapidly adapt under drug pressure within the host.IMPORTANCE Antifungal resistance is an inevitable phenomenon when fungal pathogens are exposed to antifungal drugs. These drugs can be grouped in four distinct classes (azoles, candins, polyenes, and pyrimidine analogs) and are used in different clinical settings. Failures in therapy implicate the sequential or combined use of these different drug classes, which can result in some cases in the development of multidrug resistance (MDR). MDR is particularly challenging in the clinic since it drastically reduces possible treatment alternatives. In this study, we report the rapid development of MDR in Candida lusitaniae in a patient, which became resistant to all known antifungal agents used until now in medicine. To understand how MDR developed in C. lusitaniae, whole-genome sequencing followed by comparative genome analysis was undertaken in sequential MDR isolates. This helped to detect all specific mutations linked to drug resistance and explained the different MDR patterns exhibited by the clinical isolates.


Asunto(s)
Candida/efectos de los fármacos , Candida/genética , Farmacorresistencia Fúngica/genética , Azoles/farmacología , Hibridación Genómica Comparativa , Flucitosina/farmacología , Proteínas Fúngicas/genética , Polimorfismo de Nucleótido Simple
17.
Arch Otolaryngol Head Neck Surg ; 134(1): 10-5, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18209128

RESUMEN

OBJECTIVES: To evaluate an institutional experience with perioral burns after adenotonsillectomy and to survey the national experience of other pediatric otolaryngologists regarding this complication. DESIGN: A retrospective review of adenotonsillectomy cases from January 1, 1997, to December 31, 2005, was performed to determine the incidence, etiology, severity, and treatment of perioral burns. An online national survey of pediatric otolaryngologists was conducted in May 2006 to identify their experience with perioral burns. SETTING: A tertiary pediatric medical center. PARTICIPANTS: We evaluated cases with patients younger than 18 years who developed a perioral burn during an adenotonsillectomy or tonsillectomy at Primary Children's Medical Center, Salt Lake City, Utah. MAIN OUTCOME MEASURES: Institutional and national incidence, number of injuries per physician, technique used, severity of injury, and outcomes. Comparisons were made with respect to respondent experience and techniques used. RESULTS: Seven cases of perioral burn from a single institution were identified from 4327 procedures, with 1 injury requiring reconstructive surgery. The survey response rate was 101 of 298 invitations (33.9%). Sixty-one respondents reported a total of 124 perioral burns after adenotonsillectomy. Monopolar cautery was the most common technique associated with this injury (n = 84). Coblation was the second most common technique associated with perioral burns and represented 15 (12.1%) of the reported complications. A defective electrocautery device tip was the most commonly identified cause of burn (n = 25), followed by operator error (n = 13), conduction through a metal instrument (n = 8), and lack of insulation in a cautery device (n = 7). Coblation injury was attributed to direct heat transfer from the device shaft. No significant association with operator experience was noted. A total of 14 (11.3%) of the reported injuries were severe, resulting in the need for additional treatment. CONCLUSION: Perioral burns are an underreported complication of adenotonsillectomy that can result in severe long-term morbidity.


Asunto(s)
Adenoidectomía/métodos , Quemaduras por Electricidad/etiología , Electrocoagulación/efectos adversos , Labio/lesiones , Boca/lesiones , Tonsilectomía/métodos , Análisis de Varianza , Quemaduras por Electricidad/terapia , Distribución de Chi-Cuadrado , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Estudios Retrospectivos , Encuestas y Cuestionarios
18.
Br J Soc Psychol ; 57(3): 630-651, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29601645

RESUMEN

Bidimensional attitudes have been shown to independently predict behaviour, with the positive dimension of attitude being a stronger predictor of behaviour than the negative dimension (e.g., Elliott, Brewster, et al., 2015, Br. J. Psychol, 106, 656). However, this positivity bias has been demonstrated with explicit attitude measures only and explicit attitude measures tap deliberative processes rather than automatic processes, which are known to be important in the execution of many behaviours. The aim of this study was to test whether implicit bidimensional attitudes can account for variance in speeding behaviour over and above explicit bidimensional attitudes and whether the positivity bias that is typically found with explicit attitudes generalizes to implicit attitudes. A total of 131 drivers completed a questionnaire measuring their explicit bidimensional attitudes towards speeding. They also completed Implicit Association Tests measuring their implicit bidimensional attitudes. Two weeks later, speeding behaviour was measured using a driving simulator. Explicit attitudes accounted for a significant proportion of the variance in subsequent speeding behaviour. Implicit attitudes accounted for a statistically significant increment to explained variance. The positive dimension of both explicit and implicit attitudes predicted speeding behaviour but the negative dimensions did not. Theoretical implications for understanding the potential attitudinal causes of behaviour and practical implications for behaviour-change interventions are discussed.


Asunto(s)
Actitud , Conducción de Automóvil/psicología , Conducta Social , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
19.
Wellcome Open Res ; 2: 93, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29552641

RESUMEN

Background: Many powered wheelchair users find their medical condition and their ability to drive the wheelchair will change over time. In order to maintain their independent mobility, the powered chair will require adjustment over time to suit the user's needs, thus regular input from healthcare professionals is required. These limited resources can result in the user having to wait weeks for appointments, resulting in the user losing independent mobility, consequently affecting their quality of life and that of their family and carers. In order to provide an adaptive assistive driving system, a range of features need to be identified which are suitable for initial system setup and can automatically provide data for re-calibration over the long term. Methods: A questionnaire was designed to collect information from powered wheelchair users with regard to their symptoms and how they changed over time. Another group of volunteer participants were asked to drive a test platform and complete a course which represented manoeuvring in a very confined space as quickly as possible. Two of those participants were also monitored over a longer period in their normal home daily environment. Features, thought to be suitable, were examined using pattern recognition classifiers to determine their suitability for identifying the changing user input over time. Results: The results are not designed to provide absolute insight into the individual user behaviour, as no ground truth of their ability has been determined, they do nevertheless demonstrate the utility of the measured features to provide evidence of the users' changing ability over time whilst driving a powered wheelchair. Conclusions: Determining the driving features and adjustable elements provides the initial step towards developing an adaptable assistive technology for the user when the ground truths of the individual and their machine have been learned by a smart pattern recognition system.

20.
Open Biol ; 7(4)2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28381627

RESUMEN

The fate of an mRNA is determined by its interaction with proteins and small RNAs within dynamic complexes called ribonucleoprotein complexes (mRNPs). In Trypanosoma brucei and related kinetoplastids, responses to internal and external signals are mainly mediated by post-transcriptional processes. Here, we used proximity-dependent biotin identification (BioID) combined with RNA-seq to investigate the changes resulting from ectopic expression of RBP10 and RBP9, two developmentally regulated RNA-binding proteins (RBPs). Both RBPs have reduced expression in insect procyclic forms (PCFs) compared with bloodstream forms (BSFs). Upon overexpression in PCFs, both proteins were recruited to cytoplasmic foci, co-localizing with the processing body marker SCD6. Further, both RBPs altered the transcriptome from a PCF- to a BSF-like pattern. Notably, upon expression of BirA*-RBP9 and BirA*-RBP10, BioID yielded more than 200 high confidence protein interactors (more than 10-fold enriched); 45 (RBP9) and 31 (RBP10) were directly related to mRNA metabolism. This study validates the use of BioID for investigating mRNP components but also illustrates the complexity of mRNP function.


Asunto(s)
Proteínas Protozoarias/metabolismo , Proteínas de Unión al ARN/metabolismo , Trypanosoma brucei brucei/metabolismo , Proteínas Portadoras/metabolismo , Puntos de Control del Ciclo Celular/genética , Biología Computacional/métodos , Expresión Génica , Unión Proteica , Mapeo de Interacción de Proteínas , Proteínas Protozoarias/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/genética , Transcriptoma , Trypanosoma brucei brucei/genética
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