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1.
Nature ; 540(7631): 104-108, 2016 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-27905442

RESUMEN

The majority of the Earth's terrestrial carbon is stored in the soil. If anthropogenic warming stimulates the loss of this carbon to the atmosphere, it could drive further planetary warming. Despite evidence that warming enhances carbon fluxes to and from the soil, the net global balance between these responses remains uncertain. Here we present a comprehensive analysis of warming-induced changes in soil carbon stocks by assembling data from 49 field experiments located across North America, Europe and Asia. We find that the effects of warming are contingent on the size of the initial soil carbon stock, with considerable losses occurring in high-latitude areas. By extrapolating this empirical relationship to the global scale, we provide estimates of soil carbon sensitivity to warming that may help to constrain Earth system model projections. Our empirical relationship suggests that global soil carbon stocks in the upper soil horizons will fall by 30 ± 30 petagrams of carbon to 203 ± 161 petagrams of carbon under one degree of warming, depending on the rate at which the effects of warming are realized. Under the conservative assumption that the response of soil carbon to warming occurs within a year, a business-as-usual climate scenario would drive the loss of 55 ± 50 petagrams of carbon from the upper soil horizons by 2050. This value is around 12-17 per cent of the expected anthropogenic emissions over this period. Despite the considerable uncertainty in our estimates, the direction of the global soil carbon response is consistent across all scenarios. This provides strong empirical support for the idea that rising temperatures will stimulate the net loss of soil carbon to the atmosphere, driving a positive land carbon-climate feedback that could accelerate climate change.


Asunto(s)
Atmósfera/química , Ciclo del Carbono , Carbono/análisis , Geografía , Calentamiento Global , Suelo/química , Bases de Datos Factuales , Ecosistema , Retroalimentación , Modelos Estadísticos , Reproducibilidad de los Resultados , Temperatura
2.
J Phys Chem A ; 124(35): 7031-7046, 2020 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-32786976

RESUMEN

Thin films of pentaerythritol tetranitrate (PETN) were shock compressed using the laser driven shock apparatus at Los Alamos National Laboratory (LANL). Two spectroscopic probes were available to this apparatus: visible white light transient absorption spectroscopy (VIS) from 400 to 700 nm and mid-infrared transient absorption spectroscopy (MIR) from 1150 to 3800 cm-1. Important PETN vibrational modes are the symmetric and antisymmetric NO2 stretches at 1280 and 1650 cm-1, respectively, as well as CH stretches at ∼2900 cm-1. Shock strength was varied from approximately 3 to 55 GPa to span from the chemically unreactive regime to the regime in which fast chemical reaction took place on the 250 ps time scale of the measurements. VIS and MIR results suggest irreversible chemistry was induced in PETN at pressures above 30 GPa. At lower shock pressures, the spectroscopy showed minimal changes attributable to pressure induced effects. Under the higher-pressure reactive conditions, the frequency region at the antisymmetric NO2 stretch mode had a significantly increased absorption while the region around the symmetric NO2 stretch did not. No observable increased absorption occurred in the higher frequency regions where CH-, NH-, and OH- bond absorptions would be observed. A broad absorption appeared on the shoulder at the red-edge of the CO2 vibrational band around 2200 cm-1. In addition to the experiments, reactive molecular dynamics were carried out under equivalent shock conditions to correlate the evolution of the infrared spectrum to molecular processes. The simulations show results consistent to experiments up to 30 GPa but suggest that NO and NO2 related features provided the strongest contributions to the shocked infrared changes. Proposed mechanisms for shocked PETN chemistry are analyzed as consistent or inconsistent with the data presented here. Our experimental data suggests C≡O or N2O bond formation, nitrite formation, and absence of significant hydroxyl or amine concentrations in the initial chemistry steps in PETN shocked above 30 GPa.

3.
Neural Plast ; 2019: 7092496, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30863437

RESUMEN

Continuous theta burst stimulation (cTBS) is a form of noninvasive repetitive brain stimulation that, when delivered over the contralesional hemisphere, can influence the excitability of the ipsilesional hemisphere in individuals with stroke. cTBS applied prior to skilled motor practice interventions may augment motor learning; however, there is a high degree of variability in individual response to this intervention. The main objective of the present study was to assess white matter biomarkers of response to cTBS paired with skilled motor practice in individuals with chronic stroke. We tested the effects of stimulation of the contralesional hemisphere at the site of the primary motor cortex (M1c) or primary somatosensory cortex (S1c) and a third group who received sham stimulation. Within each stimulation group, individuals were categorized into responders or nonresponders based on their capacity for motor skill change. Baseline diffusion tensor imaging (DTI) indexed the underlying white matter microstructure of a previously known motor learning network, named the constrained motor connectome (CMC), as well as the corticospinal tract (CST) of lesioned and nonlesioned hemispheres. Across practice, there were no differential group effects. However, when categorized as responders vs. nonresponders using change in motor behaviour, we demonstrated a significant difference in CMC microstructural properties (as measured by fractional anisotropy (FA)) for individuals in M1c and S1c groups. There were no significant differences between responders and nonresponders in clinical baseline measures or microstructural properties (FA) in the CST. The present study identifies a white matter biomarker, which extends beyond the CST, advancing our understanding of the importance of white matter networks for motor after stroke.


Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Corteza Motora/diagnóstico por imagen , Corteza Somatosensorial/diagnóstico por imagen , Accidente Cerebrovascular/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen , Anciano , Biomarcadores , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/terapia , Resultado del Tratamiento
4.
Public Health ; 171: 123-130, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31128557

RESUMEN

OBJECTIVE: Smokers who access free National Health Service (NHS) Stop Smoking Services (SSS) in the UK are four times more likely to stop smoking, yet uptake of the services has been in decline in recent years. Evidence was collated to explore the beliefs of smokers, ex-smokers and Stop Smoking Advisors (SSAs) about SSS and the barriers and facilitators to access. STUDY DESIGN: Mixed-methods design including i) a search of the literature; ii) a cross-sectional online questionnaire completed by 38 smokers and ex-smokers; and iii) semistructured interviews with 5 SSAs. METHODS: PubMed, Web of Science, Scopus, Prospero and the NIHR Portfolio were searched in October 2017 to identify relevant studies. Smokers and ex-smokers were recruited to the online questionnaire via Public Health websites and social media in Warwickshire. SSAs identified via Public Health Warwickshire were invited to take part in an interview conducted over the telephone. Findings were collated and analysed using the COM-B ('Capability', 'Opportunity', 'Motivation' and 'Behaviour') model framework. RESULTS: A range of practical and psychological or belief-based barriers and facilitators to accessing SSS were identified within all the components of the COM-B model, aside from physical capability, for example; 'Psychological capability', such as lack of understanding about what the service offers; 'Reflective motivation', such as lack of confidence in service efficacy; and 'Social opportunity', such as recommendations from healthcare professionals to attend. Suggestions and consideration on how future tobacco control intervention and public health messages can address these components are reported. CONCLUSIONS: Public health interventions and campaigns may benefit from focussing on addressing the well-known perceived barriers and facilitators smokers experience, in particular focussing on the components of the COM-B that have been identified as being important to increase the uptake of SSS.


Asunto(s)
Actitud Frente a la Salud , Consejeros/psicología , Ex-Fumadores/psicología , Accesibilidad a los Servicios de Salud , Fumadores/psicología , Prevención del Hábito de Fumar , Medicina Estatal , Adolescente , Adulto , Anciano , Consejeros/estadística & datos numéricos , Estudios Transversales , Ex-Fumadores/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fumadores/estadística & datos numéricos , Reino Unido , Adulto Joven
5.
J Evol Biol ; 31(1): 46-56, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29030895

RESUMEN

Antagonistic pleiotropy (AP) is a genetic trade-off between different fitness components. In annual plants, a trade-off between days to flower (DTF) and reproductive capacity often determines how many individuals survive to flower in a short growing season, and also influences the seed set of survivors. We develop a model of viability and fecundity selection informed by many experiments on the yellow monkeyflower, Mimulus guttatus, but applicable to many annual species. A viability/fecundity trade-off maintains stable polymorphism under surprisingly general conditions. We also introduce both spatial heterogeneity and temporal stochasticity in environmental parameters. Neither is necessary for polymorphism, but spatial heterogeneity allows polymorphism while also generating the often observed non-negative correlations in fitness components.


Asunto(s)
Aptitud Genética/fisiología , Pleiotropía Genética , Mimulus/fisiología , Modelos Biológicos , Mimulus/genética
6.
Eur J Neurosci ; 45(10): 1343-1355, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28370664

RESUMEN

Primary motor cortex (M1) excitability is modulated following a single session of cycling exercise. Specifically, short-interval intracortical inhibition and intracortical facilitation are altered following a session of cycling, suggesting that exercise affects the excitability of varied cortical circuits. Yet we do not know whether a session of exercise also impacts the excitability of interhemispheric circuits between, and other intracortical circuits within, M1. Here we present two experiments designed to address this gap in knowledge. In experiment 1, single and paired pulse transcranial magnetic stimulation (TMS) were used to measure intracortical circuits including, short-interval intracortical facilitation (SICF) tested at 1.1, 1.5, 2.7, 3.1 and 4.5 ms interstimulus intervals (ISIs), contralateral silent period (CSP) and interhemispheric interactions by measuring transcallosal inhibition (TCI) recorded from the abductor pollicus brevis muscles. All circuits were assessed bilaterally pre and two time points post (immediately, 30 min) moderate intensity lower limb cycling. SICF was enhanced in the left hemisphere after exercise at the 1.5 ms ISI. Also, CSP was shortened and TCI decreased bilaterally after exercise. In Experiment 2, corticospinal and spinal excitability were tested before and after exercise to investigate the locus of the effects found in Experiment 1. Exercise did not impact motor-evoked potential recruitment curves, Hoffman reflex or V-wave amplitudes. These results suggest that a session of exercise decreases intracortical and interhemispheric inhibition and increases facilitation in multiple circuits within M1, without concurrently altering spinal excitability. These findings have implications for developing exercise strategies designed to potentiate M1 plasticity and skill learning in healthy and clinical populations.


Asunto(s)
Ejercicio Físico , Lateralidad Funcional , Corteza Motora/fisiología , Adulto , Cuerpo Calloso/fisiología , Humanos , Inhibición Neural , Tractos Piramidales/fisiología
7.
Epidemiol Infect ; 145(12): 2618-2625, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28748773

RESUMEN

Varicella-zoster virus (VZV) infection (chickenpox) results in latency and subsequent reactivation manifests as shingles. Effective attenuated vaccines (vOka) are available for prevention of both illnesses. In this study, an amplicon-based sequencing method capable of differentiating between VZV wild-type (wt) strains and vOka vaccine is described. A total of 44 vesicular fluid specimens collected from 43 patients (16 from China and 27 from the UK) with either chickenpox or shingles were investigated, of which 10 had received previous vaccination. Four sets of polymerase chain reactions were set up simultaneously with primers amplifying regions encompassing four single nucleotide polymorphisms (SNPs), '69349-106262-107252-108111'. Nucleotide sequences were generated by Sanger sequencing. All samples except one had a wt SNP profile of 'A-T-T-T'. The sample collected from a patient who received vaccine 7-10 days ago, along with VZV vaccine preparations, Zostavax and Baike-varicella gave a SNP profile 'G-C-C-C'. The results show that this method can distinguish vaccine-derived virus from wt viruses from main four clades, (clades 1-4) and should be of utility worldwide.


Asunto(s)
Vacuna contra la Varicela/genética , Herpesvirus Humano 3/genética , Reacción en Cadena de la Polimerasa , Polimorfismo de Nucleótido Simple , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Varicela/virología , Vacuna contra la Varicela/clasificación , Niño , Preescolar , China , Inglaterra , Femenino , Herpes Zóster/virología , Herpesvirus Humano 3/clasificación , Humanos , Lactante , Masculino , Persona de Mediana Edad , Escocia , Análisis de Secuencia de ADN , Vacunas Atenuadas/clasificación , Vacunas Atenuadas/genética , Adulto Joven
8.
Epidemiol Infect ; 145(9): 1855-1864, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28367789

RESUMEN

In autumn 2014, enterovirus D68 (EV-D68) cases presenting with severe respiratory or neurological disease were described in countries worldwide. To describe the epidemiology and virological characteristics of EV-D68 in England, we collected clinical information on laboratory-confirmed EV-D68 cases detected in secondary care (hospitals), between September 2014 and January 2015. In primary care (general practitioners), respiratory swabs collected (September 2013-January 2015) from patients presenting with influenza-like illness were tested for EV-D68. In secondary care 55 EV-D68 cases were detected. Among those, 45 cases had clinical information available and 89% (40/45) presented with severe respiratory symptoms. Detection of EV-D68 among patients in primary care increased from 0.4% (4/1074; 95% CI 0.1-1.0) (September 2013-January 2014) to 0.8% (11/1359; 95% CI 0.4-1.5) (September 2014-January 2015). Characterization of EV-D68 strains circulating in England since 2012 and up to winter 2014/2015 indicated that those strains were genetically similar to those detected in 2014 in USA. We recommend reinforcing enterovirus surveillance through screening respiratory samples of suspected cases.


Asunto(s)
Enterovirus Humano D/aislamiento & purificación , Infecciones por Enterovirus/epidemiología , Infecciones del Sistema Respiratorio/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Inglaterra/epidemiología , Infecciones por Enterovirus/diagnóstico , Infecciones por Enterovirus/virología , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Filogenia , Prevalencia , Atención Primaria de Salud , Infecciones del Sistema Respiratorio/diagnóstico , Infecciones del Sistema Respiratorio/virología , Estaciones del Año , Atención Secundaria de Salud , Proteínas Virales de Fusión/genética , Adulto Joven
9.
Epidemiol Infect ; 144(11): 2345-53, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27018820

RESUMEN

Healthcare workers (HCWs) reporting no history of varicella frequently receive varicella vaccination (vOka) if they test varicella-zoster virus (VZV) immunoglobulin G (IgG) negative. In this study, the utilities of VZV-IgG time-resolved fluorescence immunoassay (VZV-TRFIA) and a commercial VZV-IgG purified glycoprotein enzyme immunoassay (gpEIA) currently used in England for confirming VZV immunity have been compared to the fluorescent-antibody-to-membrane-antigen assay (FAMA). A total of 110 HCWs received two doses of vOka vaccine spaced 6 weeks apart and sera collected pre-vaccination (n = 100), at 6 weeks post-completion of vaccination (n = 86) and at 12-18 months follow-up (n = 73) were analysed. Pre-vaccination, by FAMA, 61·0% sera were VZV IgG negative, and compared to FAMA the sensitivities of VZV-TRFIA and gpEIA were 74·4% [95% confidence interval (CI) 57·9-87·0] and 46·2% (95% CI 30·1-62·8), respectively. Post-completion of vaccination the seroconversion rate by FAMA was 93·7% compared to rates of 95·8% and 70·8% determined by VZV-TRFIA and gpEIA, respectively. At 12-18 months follow-up seropositivity rates by FAMA, VZV-TRFIA and gpEIA were 78·1%, 74·0% and 47·9%, respectively. Compared to FAMA the sensitivities of VZV-TRFIA and gpEIA for measuring VZV IgG following vaccination were 96·4% (95% CI 91·7-98·8) and 74·6% (95% CI 66·5-81·6), respectively. Using both FAMA and VZV-TRFIA to identify healthy adult VZV susceptibles and measure seroconversion showed that vOka vaccination of HCWs is highly immunogenic.


Asunto(s)
Anticuerpos Antivirales/sangre , Técnica del Anticuerpo Fluorescente , Fluoroinmunoensayo , Personal de Salud/estadística & datos numéricos , Técnicas para Inmunoenzimas , Inmunoglobulina G/sangre , Adulto , Vacuna contra la Varicela/inmunología , Herpesvirus Humano 3/inmunología , Humanos , Persona de Mediana Edad , Adulto Joven
10.
Health Educ Res ; 31(2): 273-82, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26928566

RESUMEN

Sexual health service access is fundamental to good sexual health, yet interventions designed to address this have rarely been implemented or evaluated. In this article, pilot evaluation findings for a targeted public health behavior change intervention, delivered via a website and web-app, aiming to increase uptake of sexual health services among 13-19-year olds are reported. A pre-post questionnaire-based design was used. Matched baseline and follow-up data were identified from 148 respondents aged 13-18 years. Outcome measures were self-reported service access, self-reported intention to access services and beliefs about services and service access identified through needs analysis. Objective service access data provided by local sexual health services were also analyzed. Analysis suggests the intervention had a significant positive effect on psychological barriers to and antecedents of service access among females. Males, who reported greater confidence in service access compared with females, significantly increased service access by time 2 follow-up. Available objective service access data support the assertion that the intervention may have led to increases in service access. There is real promise for this novel digital intervention. Further evaluation is planned as the model is licensed to and rolled out by other local authorities in the United Kingdom.


Asunto(s)
Accesibilidad a los Servicios de Salud/organización & administración , Internet , Servicios de Salud Reproductiva/organización & administración , Adolescente , Femenino , Humanos , Conducta en la Búsqueda de Información , Masculino , Aplicaciones Móviles , Proyectos Piloto , Factores Sexuales , Conducta Sexual , Reino Unido
11.
Virus Genes ; 50(1): 2-11, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25663095

RESUMEN

The World Health Organization (WHO) has adopted an elimination goal for measles and rubella, which is supposed to be met in the WHO European Region (EUR) by 2015. For verification of elimination, it is required that the genotyping data of detected measles viruses provide evidence for the interruption of endemic transmission. In order to record and assess the extent of endemic measles virus (MV) circulation in a part of the EUR, we analyzed transmission chains of the epidemiologically most relevant MV variants identified in Central and continental Western Europe (CCWE) from 2006 to 2013. Based on MV sequence data deposited in the WHO global database for molecular surveillance of measles (MeaNS), the circulation period was calculated for each MV variant at the country-level and for the entire region of CCWE. The MV variants "D5-Okinawa," "D4-Hamburg," "D4-Manchester," and "D8-Frankfurt-Main" spread widely in CCWE; they caused large and long-lasting outbreaks with secondary spread that resulted in additional outbreaks. Nation-wide outbreaks (epidemics) with thousands of measles cases occurred in four countries (Switzerland, France, Bulgaria, and Romania) and were characterized by continuous detection of the same MV variant for more than 12 months suggesting endemic transmission. In the entire region of CCWE, the circulation period of the four predominant MV variants ranged from 18 to 44 months. The long-lasting MV transmission which affected predominantly unvaccinated individuals in different hard-to-reach groups and in the general population is not consistent with the measles elimination goal. Additional efforts are necessary to meet the elimination target in the EUR.


Asunto(s)
Brotes de Enfermedades , Monitoreo Epidemiológico , Virus del Sarampión/aislamiento & purificación , Sarampión/epidemiología , Sarampión/transmisión , Enfermedades Endémicas , Europa (Continente)/epidemiología , Genotipo , Humanos , Virus del Sarampión/clasificación , Virus del Sarampión/genética , Epidemiología Molecular
12.
Euro Surveill ; 20(31)2015 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-26290428

RESUMEN

Influenza A(H3N2) virus was detected in oral fluid from 16/107 children (aged 2 to 12 years) with a clinical diagnosis of mumps, who were sampled between December 2014 and February 2015 in England, during the peak of the 2014/15 influenza season. Sequence analysis of an A(H3N2) virus from a child with suspected mumps showed the virus was similar to other circulating A(H3N2) viruses detected in winter 2014/15, which were antigenically drifted from the A(H3N2) vaccine strain.


Asunto(s)
Subtipo H3N2 del Virus de la Influenza A/aislamiento & purificación , Gripe Humana/diagnóstico , Paperas/epidemiología , Vigilancia de la Población , Niño , Preescolar , Coinfección , Brotes de Enfermedades , Inglaterra/epidemiología , Humanos , Subtipo H3N2 del Virus de la Influenza A/genética , Gripe Humana/complicaciones , Masculino , Virus de la Parotiditis , Filogenia , ARN Viral/genética , Estaciones del Año , Análisis de Secuencia de ADN
13.
Perspect Public Health ; 143(6): 347-357, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37902308

RESUMEN

AIMS: Obesity contributes to morbidity and early mortality, affecting people of all ages and sociodemographic backgrounds. Despite attempts to address obesity, efforts to date have only had limited success. Adopting a whole systems approach (WSA) may potentially address obesity and emphasise complex inter-relating factors beyond individual choice. This study aimed to assess implementation of WSA to diet and healthy weight in two council areas of Scotland, longitudinally exploring enablers and barriers. One area followed a Leeds Beckett WSA model (LBM) of implementation, while the other used a hybrid model incorporating existing working systems. METHODS: To assess the process of implementing a WSA, interviews and focus groups were conducted after initiation and 1 year later. RESULTS: Main enablers included: belief in WSA effectiveness; positive relationships between key personnel; buy-in at community and national levels; funding availability; the working group responsible for coordinating the system development comprising individuals with diverse expertise; good communication; and existing governance structures. Barriers included: insufficient funding; high staff turnover; inadequate training in WSA methodology; engaging all relevant stakeholders and reverting to 'old ways' of non-WSA working. The LBM provided a framework for system setup and generating an action plan. CONCLUSION: This study provides the first independent longitudinal process evaluation of WSAs that have incorporated Leeds Beckett methodology, and offers insights into how a WSA can be implemented to address diet and healthy weight.


Asunto(s)
Dieta , Obesidad , Humanos , Escocia , Obesidad/epidemiología , Obesidad/prevención & control , Grupos Focales , Análisis de Sistemas
14.
Science ; 379(6630): 393-398, 2023 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-36701449

RESUMEN

Rapid evolution remains a largely unrecognized factor in models that forecast the fate of ecosystems under scenarios of global change. In this work, we quantified the roles of heritable variation in plant traits and of trait evolution in explaining variability in forecasts of the state of coastal wetland ecosystems. A common garden study of genotypes of the dominant sedge Schoenoplectus americanus, "resurrected" from time-stratified seed banks, revealed that heritable variation and evolution explained key ecosystem attributes such as the allocation and distribution of belowground biomass. Incorporating heritable trait variation and evolution into an ecosystem model altered predictions of carbon accumulation and soil surface accretion (a determinant of marsh resilience to sea level rise), demonstrating the importance of accounting for evolutionary processes when forecasting ecosystem dynamics.


Asunto(s)
Plantas , Elevación del Nivel del Mar , Humedales , Plantas/genética , Suelo
15.
Euro Surveill ; 17(40): 20292, 2012 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-23078799

RESUMEN

On 22 September 2012, a novel coronavirus, very closely related to that from a fatal case in Saudi Arabia three months previously, was detected in a previously well adult transferred to intensive care in London from Qatar with severe respiratory illness. Strict respiratory isolation was instituted. Ten days after last exposure, none of 64 close contacts had developed severe disease, with 13 of 64 reporting mild respiratory symptoms. The novel coronavirus was not detected in 10 of 10 symptomatic contacts tested.


Asunto(s)
Técnicas de Laboratorio Clínico , Infecciones por Coronavirus/diagnóstico , Coronavirus/aislamiento & purificación , Práctica de Salud Pública , Síndrome Respiratorio Agudo Grave/diagnóstico , Viaje , Adulto , Infecciones por Coronavirus/virología , Humanos , Londres , Masculino , Arabia Saudita , Síndrome Respiratorio Agudo Grave/virología , Reino Unido
16.
Nat Cell Biol ; 3(6): 602-6, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11389446

RESUMEN

The alpha- and beta-globin gene clusters have been extensively studied. Regulation of these genes ensures that proteins derived from both loci are produced in balanced amounts, and that expression is tissue-restricted and specific to developmental stages. Here we compare the subnuclear location of the endogenous alpha- and beta-globin loci in primary human cells in which the genes are either actively expressed or silent. In erythroblasts, the alpha- and beta-globin genes are localized in areas of the nucleus that are discrete from alpha-satellite-rich constitutive heterochromatin. However, in cycling lymphocytes, which do not express globin genes, the distribution of alpha- and beta-globin genes was markedly different. beta-globin loci, in common with several inactive genes studied here (human c-fms and SOX-1) and previously (mouse lambda5, CD4, CD8alpha, RAGs, TdT and Sox-1), were associated with pericentric heterochromatin in a high proportion of cycling lymphocytes. In contrast, alpha-globin genes were not associated with centromeric heterochromatin in the nucleus of normal human lymphocytes, in lymphocytes from patients with alpha-thalassaemia lacking the regulatory HS-40 element or entire upstream region of the alpha-globin locus, or in mouse erythroblasts and lymphocytes derived from human alpha-globin transgenic mice. These data show that the normal regulated expression of alpha- and beta-globin gene clusters occurs in different nuclear environments in primary haemopoietic cells.


Asunto(s)
Núcleo Celular/fisiología , Globinas/genética , Células Madre Hematopoyéticas/fisiología , Células Cultivadas , Expresión Génica , Humanos , Linfocitos/fisiología
17.
Euro Surveill ; 16(17)2011 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-21543045

RESUMEN

During late 2010, a previously unrecognised strain of measles genotype G3 virus was identified in five different European countries by the World Health Organization Measles and Rubella Laboratory Network.Apart from one, none had a travel history to south-east Asia, the usual source of G3 viruses, although epidemiological links could be established between some of the cases. This case series illustrates the value of genotyping and sequencing in tracking measles infections, and identifying otherwise unrecognised chains of transmission.


Asunto(s)
Virus del Sarampión/aislamiento & purificación , Sarampión/epidemiología , Sarampión/genética , Europa (Continente)/epidemiología , Genotipo , Humanos , Sarampión/diagnóstico , Virus del Sarampión/genética , Filogenia , Factores de Tiempo
18.
Science ; 262(5130): 114-7, 1993 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-8211117

RESUMEN

The pathogenic human parvovirus B19 replicates only in erythroid progenitor cells. This virus was shown to bind to blood-group P antigen, as measured by hemagglutination. Erythrocytes lacking P antigen were not agglutinated with B19. Purified P antigen (globoside) blocked the binding of the virus to erythroid cells and the infectivity of the virus in a hematopoietic colony assay. Target cells were protected from infection by preincubation with monoclonal antibody to globoside. Knowledge of a parvovirus receptor has implications for understanding the pathogenesis of parvovirus infections and for the use of parvoviruses in gene therapy.


Asunto(s)
Membrana Eritrocítica/microbiología , Globósidos/metabolismo , Sistema del Grupo Sanguíneo P/metabolismo , Parvovirus B19 Humano/metabolismo , Receptores Virales/metabolismo , Anticuerpos Monoclonales , Cápside/metabolismo , Secuencia de Carbohidratos , Efecto Citopatogénico Viral , Membrana Eritrocítica/inmunología , Células Precursoras Eritroides/citología , Células Precursoras Eritroides/microbiología , Globósidos/inmunología , Globósidos/farmacología , Hemaglutinación , Humanos , Datos de Secuencia Molecular , Sistema del Grupo Sanguíneo P/inmunología , Parvovirus B19 Humano/inmunología , Parvovirus B19 Humano/fisiología , Fenotipo
19.
Equine Vet J ; 41(8): 729-34, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20095218

RESUMEN

REASONS FOR PERFORMING STUDY: Little is known about the efficacy of bilateral ventriculectomy (VE) or bilateral ventriculocordectomy (VCE) in draught horses. OBJECTIVES: To compare the effect of VE and VCE on upper airway noise in draught horses with recurrent laryngeal neuropathy (RLN) by use of quantitative sound analysis techniques. HYPOTHESIS: In competitive draught horses with grade 4 RLN, VE and VCE reduce upper airway noise during exercise, but VCE is more effective. METHODS: Thirty competitive hitch or pulling draught horses with grade 4 RLN were evaluated for upper airway sound during exercise. Respiratory rate (RR), inspiratory (Ti) and expiratory time (Te), the ratio between Ti and Te (Ti/Te), inspiratory (Sli) and expiratory sound levels (Sle), the ratio between Sli and Sle (Sli/Sle), and peak sound intensity of the second formant (F2) were calculated. Eleven horses were treated with VE and 19 with VCE. After 90 days of voice and physical rest and 30 days of work, the horses returned for post operative upper airway sound evaluation and resting videoendoscopy. RESULTS: VE significantly reduced Ti/Te, Sli, Sli/Sle and the sound intensity of F2. Respiratory rate, Ti, Te and Sle were unaffected by VE. VCE significantly reduced Ti/Te, Ti, Te, Sli, Sli/Sle and the sound intensity of F2, while RR and Sle were unaffected. The reduction in sound intensity of F2 following VCE was significantly greater than following VE. After VE and VCE, 7/11 (64%) and 15/18 (83%) owners, respectively, concluded that the surgery improved upper airway sound in their horses sufficiently for successful competition. CONCLUSIONS: VE and VCE significantly reduce upper airway noise and indices of airway obstruction in draught horses with RLN, but VCE is more effective than VE. The procedures have few post operative complications. POTENTIAL RELEVANCE: VCE is recommended as the preferred treatment for RLN in draught horses. Further studies are required to evaluate the longevity of the procedure's results.


Asunto(s)
Enfermedades de los Caballos/cirugía , Ruidos Respiratorios/veterinaria , Parálisis de los Pliegues Vocales/veterinaria , Animales , Femenino , Caballos , Masculino , Parálisis de los Pliegues Vocales/cirugía , Pliegues Vocales/cirugía
20.
Rev Sci Instrum ; 90(6): 063001, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31254979

RESUMEN

Common Ti:sapphire chirped pulse amplified laser systems can be readily adapted to be both a generator of adjustable pressure shock waves and a source for multiple probes of the ensuing ultrafast shock dynamics. In this paper, we detail experimental considerations for optimizing the shock generation, interferometric characterization, and spectroscopic probing of shock dynamics with visible and mid-infrared transient absorption. While we have reported results using these techniques elsewhere, here we detail how the spectroscopies are integrated with the shock and interferometry experiment. The interferometric characterization uses information from beams at multiple polarizations and angles of incidence combined with thin film equations and shock dynamics to determine the shock velocity, particle velocity, and shocked refractive index. Visible transient absorption spectroscopy uses a white light supercontinuum in a reflection geometry, synchronized to the shock wave, to time resolve shock-induced changes in visible absorption such as changes to electronic structure or strongly absorbing products and intermediates due to reaction. Mid-infrared transient absorption spectroscopy uses two color filamentation supercontinuum generation combined with a simple thermal imaging microbolometer spectrometer to enable broadband single shot detection of changes in the vibrational spectra. These methods are demonstrated here in the study of shock dynamics at stresses from 5 to 30 GPa in organic materials and from a few GPa to >70 GPa in metals with spatial resolution of a few micrometers and temporal resolution of a few picoseconds. This experiment would be possible to replicate in any ultrafast laser laboratory containing a single bench top commercial chirped pulse amplification laser system.

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