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1.
BMJ Open ; 14(3): e081079, 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38521526

RESUMEN

INTRODUCTION: In low-income and middle-income countries in Southeast Asia, the burden of diseases among rural population remains poorly understood, posing a challenge for effective healthcare prioritisation and resource allocation. Addressing this knowledge gap, the South and Southeast Asia Community-based Trials Network (SEACTN) will undertake a survey that aims to determine the prevalence of a wide range of non-communicable and communicable diseases, as one of the key initiatives of its first project-the Rural Febrile Illness project (RFI). This survey, alongside other RFI studies that explore fever aetiology, leading causes of mortality, and establishing village and health facility maps and profiles, will provide an updated epidemiological background of the rural areas where the network is operational. METHODS AND ANALYSIS: During 2022-2023, a cross-sectional household survey will be conducted across three SEACTN sites in Bangladesh, Cambodia and Thailand. Using a two-stage cluster-sampling approach, we will employ a probability-proportional-to-size sample method for village, and a simple random sample for household, selection, enrolling all members from the selected households. Approximately 1500 participants will be enrolled per country. Participants will undergo questionnaire interview, physical examination and haemoglobin point-of-care testing. Blood samples will be collected and sent to central laboratories to test for chronic and acute infections, and biomarkers associated with cardiovascular disease, and diabetes. Prevalences will be presented as an overall estimate by country, and stratified and compared across sites and participants' sociodemographic characteristics. Associations between disease status, risk factors and other characteristics will be explored. ETHICS AND DISSEMINATION: This study protocol has been approved by the Oxford Tropical Research Ethics Committee, National Research Ethics Committee of Bangladesh Medical Research Council, the Cambodian National Ethics Committee for Health Research, the Chiang Rai Provincial Public Health Research Ethical Committee. The results will be disseminated via the local health authorities and partners, peer-reviewed journals and conference presentations. TRIAL REGISTRATION NUMBER: NCT05389540.


Asunto(s)
Costo de Enfermedad , Población Rural , Humanos , Bangladesh/epidemiología , Cambodia/epidemiología , Estudios Transversales , Encuestas Epidemiológicas , Tailandia
2.
Biomimetics (Basel) ; 8(5)2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37754190

RESUMEN

Attachment to the substrate is an important phenomenon that determines the survival of many organisms. Most insects utilize wet adhesion to support attachment, which is characterized by fluids that are secreted into the interface between the tarsus and the substrates. Previous research has investigated the composition and function of tarsal secretions of different insect groups, showing that the secretions are likely viscous emulsions that contribute to attachment by generating capillary and viscous adhesion, leveling surface roughness and providing self-cleaning of the adhesive systems. Details of the structural organization of these secretions are, however, largely unknown. Here, we analyzed footprints originating from the arolium and euplantulae of the stick insect Medauroidea extradentata using cryo-scanning electron microscopy (cryo-SEM) and white light interferometry (WLI). The secretion was investigated with cryo-SEM, revealing four morphologically distinguishable components. The 3D WLI measurements of the droplet shapes and volumes over time revealed distinctly different evaporation rates for different types of droplets. Our results indicate that the subfunctionalization of the tarsal secretion is facilitated by morphologically distinct components, which are likely a result of different proportions of components within the emulsion. Understanding these components and their functions may aid in gaining insights for developing adaptive and multifunctional biomimetic adhesive systems.

3.
J Exp Biol ; 226(3)2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36606728

RESUMEN

Stick and leaf insects (Phasmatodea) are exclusively herbivores. As they settle in a broad range of habitats, they need to attach to and walk on a wide variety of plant substrates, which can vary in their surface free energy (SFE). The adhesive microstructures (AMs) on the euplantulae of phasmids are assumed to be adapted to such substrate properties. Moreover, the natural substrates can often be covered with water as a result of high relative humidity or rain. Although considerable experimental research has been carried out on different aspects of stick insect attachment, the adaptations to cope with the influence of flooded water on attachment performance remain unclear. To elucidate the role of AMs in this context, we here measured attachment forces in three species of stick insects with different AMs. The results show that attachment forces of the three species studied were influenced by the SFE and the presence of water: they all showed higher pull-off (vertical) and traction (horizontal) forces on dry surfaces, compared with when the surfaces were covered with a water film. However, the extent to which the surface properties influenced attachment differed depending on the species and its AMs. All three species showed approximately the same attachment performance on dry surfaces with different surface free energy but maintained attachment underwater to different extents.


Asunto(s)
Adhesivos , Insectos , Animales , Fenómenos Biomecánicos , Propiedades de Superficie , Agua , Adhesividad
4.
BMJ Paediatr Open ; 6(1)2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-36053594

RESUMEN

BACKGROUND: Young children with neurodisability commonly experience eating, drinking and swallowing difficulties (EDSD). Little is documented about which interventions and outcomes are most appropriate for such children. We aimed to seek consensus between parents of children with neurodisability and health professionals on the appropriate interventions and outcomes to inform future clinical developments and research studies. METHODS: Two populations were sampled: parents of children aged up to 12 years with neurodisability who experienced EDSD; health professionals working with children and young people (aged 0-18 years) with neurodisability with experience of EDSD. Participants had taken part in a previous national survey and were invited to take part in a Delphi survey and/or consultation workshops. Two rounds of this Delphi survey sought agreement on the appropriate interventions and outcomes for use with children with neurodisability and EDSD. Two stakeholder consultation workshops were iterative, with the findings of the first discussed at the second, and conclusions reached. RESULTS: A total of 105 parents and 105 health professionals took part. Parents and health professionals viewed 19 interventions and 10 outcomes as essential. Interventions related to improvement in the physical aspects of a child's EDSD, behavioural changes of the child or parent, and changes in the child or family's well-being. Both parents and health professionals supported a 'toolkit' of interventions that they could use together in shared decision making to prioritise and implement timely interventions appropriate to the child. CONCLUSIONS: This study identified interventions viewed as essential to consider for improving EDSD in children with neurodisability. It also identified several key outcomes that are valued by parents and health professionals. The Focus on Early Eating, Drinking and Swallowing (FEEDS) Toolkit of interventions to improve EDSD in children with neurodisability has been developed and now requires evaluation regarding its use and effectiveness.


Asunto(s)
Sordera , Trastornos de Deglución , Personas con Discapacidad , Adolescente , Niño , Preescolar , Deglución , Trastornos de Deglución/terapia , Personal de Salud , Humanos , Padres , Derivación y Consulta
5.
BMJ Open ; 11(7): e045900, 2021 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-34233975

RESUMEN

INTRODUCTION: In the Greater Mekong Subregion, adults are at highest risk for malaria. The most relevant disease vectors bite during daytime and outdoors which makes forest work a high-risk activity for malaria. The absence of effective vector control strategies and limited periods of exposure during forest visits suggest that chemoprophylaxis could be an appropriate strategy to protect forest goers against malaria. METHODS AND ANALYSIS: The protocol describes an open-label randomised controlled trial of artemether-lumefantrine (AL) versus multivitamin as prophylaxis against malaria among forest goers aged 16-65 years in rural northeast Cambodia. The primary objective is to compare the efficacy of the artemisinin combination therapy AL versus a multivitamin preparation as defined by the 28-day PCR parasite positivity rate and incidence of confirmed clinical malaria of any species. The sample size is 2200 patient-episodes of duration 1 month in each arm. The duration of follow-up and prophylaxis for each participant is 1, 2 or 3 consecutive 28-day periods, followed by a further 28 days of post-exposure prophylaxis, depending on whether they continue to visit the forest. Analysis will be done both by intention to treat and per protocol. ETHICS AND DISSEMINATION: All participants will provide written, informed consent. Ethical approval was obtained from the Oxford Tropical Research Ethics Committee and the Cambodia National Ethics Committee for Health Research. Results will be disseminated by peer-reviewed open access publication together with open data. TRIAL REGISTRATION NUMBER: NCT04041973; Pre-result.


Asunto(s)
Antimaláricos , Malaria Falciparum , Malaria , Adulto , Antimaláricos/uso terapéutico , Arteméter/uso terapéutico , Combinación Arteméter y Lumefantrina/uso terapéutico , Cambodia , Bosques , Humanos , Malaria/tratamiento farmacológico , Malaria/prevención & control , Malaria Falciparum/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
6.
Health Technol Assess ; 25(22): 1-208, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33769272

RESUMEN

BACKGROUND: Eating, drinking and swallowing difficulties are common in young children with neurodisability. These difficulties may lead to inadequate calorie intake, which affects a child's nutrition, growth and general physical health. OBJECTIVE: To examine which interventions are available that can be delivered at home by parents to improve eating, drinking and swallowing in young children with neurodisability and are suitable for investigation in pragmatic trials. DESIGN: This was a mixed-methods study that included focus groups, surveys, an update of published systematic reviews of interventions, a systematic review of measurement properties of existing tools, evidence mapping, evidence synthesis, a Delphi survey and stakeholder workshops. SETTING: The study was carried out in NHS hospitals, community services, family homes and schools. PARTICIPANTS: Parents of children who had neurodisability and eating, drinking and swallowing difficulties. Professionals from health and education. Young people with eating, drinking and swallowing difficulties or young people who had previously experienced eating, drinking and swallowing difficulties. DATA SOURCES: Literature reviews; national surveys of parents and professionals; focus groups with parents, young people and professionals; and stakeholder consultation workshops. REVIEW METHODS: An update of published systematic reviews of interventions (searched July-August 2017), a mapping review (searched October 2017) and a systematic review of measurement properties using COnsensus-based Standards for the Selection of health status Measurement INstruments (COSMIN) methodology (searched May 2018). RESULTS: Significant limitations of the available research evidence regarding interventions and tools to measure outcomes were identified. A total of 947 people participated: 400 parents, 475 health professionals, 62 education professionals and 10 young people. The survey showed the wide range of interventions recommended by NHS health professionals, with parents and professionals reporting variability in the provision of these interventions. Parents and professionals considered 19 interventions as relevant because they modified eating, drinking and swallowing difficulties. Parents and professionals considered 10 outcomes as important to measure (including Nutrition, Growth and Health/safety); young people agreed that these were important outcomes. Stakeholder consultation workshops identified that project conclusions and recommendations made sense, were meaningful and were valued by parents and professionals. Parents and health professionals were positive about a proposed Focus on Early Eating, Drinking and Swallowing (FEEDS) toolkit of interventions that, through shared decision-making, could be recommended by health professionals and delivered by families. LIMITATIONS: The national surveys included large numbers of parents and professionals but, as expected, these were not representative of the UK population of parents of children with eating, drinking and swallowing difficulties. Owing to the limitations of research evidence, pragmatic decisions were made about interventions that might be included in future research and outcomes that might be measured. For instance, the reviews of research found only weak or poor evidence to support the effectiveness of interventions. The review of outcome measures found only limited low-level evidence about their psychometric properties. CONCLUSIONS: Opportunities and challenges for conducting clinical trials of the effectiveness of the FEEDS toolkit of interventions are described. Parents and professionals thought that implementation of the toolkit as part of usual NHS practice was appropriate. However, this would first require the toolkit to be operationalised through development as a complex intervention, taking account of constituent interventions, delivery strategies, implementation and manualisation. Subsequently, an evaluation of its clinical effectiveness and cost-effectiveness could be undertaken using appropriate research methods. FUTURE WORK: Initial steps include FEEDS toolkit development and evaluation of its use in clinical practice, and identification of the most robust methods to measure valued outcomes, such as Nutrition and Growth. TRIAL REGISTRATION: Current Controlled Trials ISRCTN10454425. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 22. See the NIHR Journals Library website for further project information.


Some young children with disabilities, such as those with cerebral palsy and autism spectrum disorder, have difficulties with eating, drinking and swallowing. Many strategies are employed to help with these difficulties (e.g. 'Positioning'), but we need to know more about which ones work best. We wanted to find out about the strategies parents use at home to help their children with eating, drinking and swallowing difficulties. We wanted to understand what is already known about the strategies that are available now and if children are getting the right help. We wanted to find out if doing more research would tell us which interventions work. We looked at what has been written about the ways in which parents help their child to eat, drink and swallow. We discussed this information with parents and health professionals. We developed a survey to ask what parent-delivered strategies are recommended by NHS professionals, which strategies parents use and how we would know if things had improved. We discussed the findings with parents and professionals. We then used a different type of survey. Parents and professionals were asked which strategies were most important and what they would most like to improve. We then held workshops to hear parents' and professionals' views on what we had found and to agree on how we would organise future research. We discussed some of the findings with young people. Research about these strategies and how to measure improvements in eating and drinking is of poor quality. A wide variety of strategies are used: 19 strategies were thought to be the most useful by parents and professionals. Parents and professionals agreed on 10 areas that they would most like to improve. Both groups thought that it was a good idea to have a 'toolkit' of strategies so that they could choose the right strategy at the right time.


Asunto(s)
Deglución , Padres , Adolescente , Niño , Preescolar , Humanos , Evaluación de Resultado en la Atención de Salud , Encuestas y Cuestionarios , Evaluación de la Tecnología Biomédica
7.
Clin Nutr ESPEN ; 42: 138-141, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33745567

RESUMEN

BACKGROUND: Use of HPN in paediatrics in the UK has increased rapidly over the last 20 years but the prevalence of HPN has been challenging to define. Clinicians in the UK have noted an evolving complexity of cases and perceive improved outcomes and increased acceptability of long-term PN. These factors combined have the potential to increase the burden on existing paediatric gastroenterology services in the UK. METHODS: A national database was interrogated to define the prevalence of HPN in children in the UK and to explore outcomes for patients receiving HPN. RESULTS: Since 2015, 525 children were notified to the database; of these patients, mortality was <5% and intestinal transplant occurred in 1%. In 2019, 389 children received HPN in the UK; this is nearly double the number last reported in 2012 and is a prevalence of 30 per million children. Short bowel syndrome is the largest category of these patients. However, a poorly defined group including those with multisystem disease has increased 10 fold since 2012 and is now the second largest category. CONCLUSIONS: Long term HPN in childhood is safe and associated with good survival and low risk of the need for intestinal transplantation.


Asunto(s)
Nutrición Parenteral en el Domicilio , Síndrome del Intestino Corto , Niño , Humanos , Intestinos , Nutrición Parenteral en el Domicilio/efectos adversos , Prevalencia , Riesgo , Síndrome del Intestino Corto/epidemiología , Síndrome del Intestino Corto/terapia
8.
Front Physiol ; 10: 612, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31214040

RESUMEN

Transport processes between aquaculture facilities activate the stress response in fish. To deal with these situations, the hypothalamic-pituitary-interrenal (HPI) axis releases cortisol, leading to an increase in circulating energy resources to restore homeostasis. However, if the allostatic load generated exceeds fish tolerance limits, stress-related responses will compromise health and welfare of the animals. In this context, anesthetics have arisen as potential agents aiming to reduce negative effects of stress response. Here we assessed the effects of a sedative dose of clove oil (CO) and MS-222 on hallmarks involved in HPI axis regulation and energy management after simulated transport, and further recovery, in gilthead seabream (Sparus aurata L.) juveniles. Fish were placed in a mobile setup of water tanks where transport conditions were simulated for 6 h. Sedation doses of either CO (2.5 mg L-1) or MS-222 (5 mg L-1) were added in the water tanks. A control group without anesthetics was also included in the setup. Half of the animals (n = 12 per group) were sampled immediately after transport, while remaining animals were allowed to recover for 18 h in clean water tanks and then sampled. Our results showed that the HPI axis response was modified at peripheral level, with differences depending on the anesthetic employed. Head kidney gene-expressions related to cortisol production (star and cyp11b1) matched concomitantly with increased plasma cortisol levels immediately after transport in CO-sedated fish, but these levels remained constant in MS-222-sedated fish. Differential changes in the energy management of carbohydrates, lipids and amino acids, depending on the anesthetic employed, were also observed. The use of CO stimulated amino acids catabolism, while MS-222-sedated fish tended to consume liver glycogen and mobilize triglycerides. Further studies, including alternative doses of both anestethics, as well as the assessment of time-course HPI activation and longer recovery periods, are necessary to better understand if the use of clove oil and MS-222 is beneficial for S. aurata under these circumstances.

9.
BMC Med Educ ; 18(1): 276, 2018 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-30466411

RESUMEN

Following publication of the original article [1], the author reported that Fig. 1 was missing.

10.
BMC Med Educ ; 18(1): 236, 2018 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-30309368

RESUMEN

BACKGROUND: Promoting cultural competence of health professionals working with Aboriginal and Torres Strait Islander communities is key to improving health outcomes. Cultural Educators and Cultural Mentors (CE/ CMs) have critical roles in Australian general practice training, yet these are not well understood. METHODS: Guided by a CE/CM Network, our research team including experienced CE/CMs, used surveys and semi-structured interviews to explore these roles and investigate best practice in employment and support. Participants sampled from stakeholders involved in general practice education across Australia included CE/CMs, Medical Educators, General Practice Supervisors and Registrars, and representatives of Regional Training Organisations, Indigenous Health Training Posts and other key organisations. We undertook thematic analysis using a framework approach, refined further in team discussions that privileged views of CE/ CM members. RESULTS: Participants comprised 95 interviewees and 55 survey respondents. We organised our findings under three overarching themes: understandings about cultural education and mentoring; employment and support of CE/CMs; and delivery and evaluation of cultural education and mentoring. Our findings supported a central role for Aboriginal and Torres Strait Islander CE/CMs in face-to-face Registrar education about culture and history and related impacts on health and healthcare. Cultural education was reported to provide base-line learning as preparation for clinical practice whilst cultural mentoring was seen as longitudinal, relationship-based learning. Mentoring was particularly valued by Registrars working in Aboriginal and Torres Strait Islander communities. Challenges described with employment and support included difficulties in finding people with skills and authority to undertake this demanding work. Remuneration was problematic, particularly for CMs whose work-time is difficult to quantify, and who are often employed in other roles and sometimes not paid. Other improved support recommended included appropriate employment terms and conditions, flexibility in role definitions, and professional development. Recommendations concerning implementation and evaluation included valuing of cultural education, greater provision of mentoring, partnerships with Medical Educators, and engagement of CE/CMs in rigorous evaluation and assessment processes. CONCLUSIONS: Our research highlights the importance of the unique CE/CM roles and describes challenges in sustaining them. Professional and organisational support is needed to ensure delivery of respectful and effective cultural education within general practitioner training.


Asunto(s)
Actitud del Personal de Salud , Competencia Cultural/educación , Medicina General/educación , Servicios de Salud del Indígena , Mentores , Nativos de Hawái y Otras Islas del Pacífico , Australia , Asistencia Sanitaria Culturalmente Competente , Educación Médica/métodos , Humanos , Entrevistas como Asunto , Encuestas y Cuestionarios
13.
Theor Appl Genet ; 129(8): 1507-17, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27160855

RESUMEN

KEY MESSAGE: SNP markers were developed for the OWBM resistance gene Sm1 that will be useful for MAS. The wheat Sm1 region is collinear with an inverted syntenic interval in B. distachyon. Orange wheat blossom midge (OWBM, Sitodiplosis mosellana Géhin) is an important insect pest of wheat (Triticum aestivum) in many growing regions. Sm1 is the only described OWBM resistance gene and is the foundation of managing OWBM through host genetics. Sm1 was previously mapped to wheat chromosome arm 2BS relative to simple sequence repeat (SSR) markers and the dominant, sequence characterized amplified region (SCAR) marker WM1. The objectives of this research were to saturate the Sm1 region with markers, develop improved markers for marker-assisted selection (MAS), and examine the synteny between wheat, Brachypodium distachyon, and rice (Oryza sativa) in the Sm1 region. The present study mapped Sm1 in four populations relative to single nucleotide polymorphisms (SNPs), SSRs, Diversity Array Technology (DArT) markers, single strand conformation polymorphisms (SSCPs), and the SCAR WM1. Numerous high quality SNP assays were designed that mapped near Sm1. BLAST delineated the syntenic intervals in B. distachyon and rice using gene-based SNPs as query sequences. The Sm1 region in wheat was inverted relative to B. distachyon and rice, which suggests a chromosomal rearrangement within the Triticeae lineage. Seven SNPs were tested on a collection of wheat lines known to carry Sm1 and not to carry Sm1. Sm1-flanking SNPs were identified that were useful for predicting the presence or absence of Sm1 based upon haplotype. These SNPs will be a major improvement for MAS of Sm1 in wheat breeding programs.


Asunto(s)
Mapeo Cromosómico , Ligamiento Genético , Polimorfismo de Nucleótido Simple , Sintenía , Triticum/genética , Animales , Brachypodium/genética , Chironomidae , ADN de Plantas/genética , Genes de Plantas , Marcadores Genéticos , Haplotipos , Oryza/genética , Fenotipo
14.
Theor Appl Genet ; 129(3): 485-93, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26660463

RESUMEN

KEY MESSAGE: Genetic and mutational analyses of wheat leaf rust resistance gene Lr13 and hybrid necrosis gene Ne2 m indicated that they are the same gene. Hybrid necrosis in wheat characterized by chlorosis and eventual necrosis of plant tissues in certain wheat hybrids is controlled by the interaction of complementary dominant genes Ne1 and Ne2 located on chromosome arms 5BL and 2BS, respectively. Multiple alleles at each locus can be identified by differences in necrotic phenotypes when varieties are crossed with a fixed accession of the other genotype. Some of at least five Ne2 alleles were described as s (strong), m (medium) and w (weak); alleles of Ne1 were similarly described. Ne2m causes moderate necrosis in hybrids with genotypes having Ne1s. Ne2 is located on chromosome arm 2BS in close proximity to Lr13. Most wheat lines with Ne2m carry Lr13, and all wheat lines with Lr13 appear to carry Ne2m. To further dissect the relationship between Lr13 and Ne2m, more than 350 crosses were made between cv. Spica (Triticum aestivum) or Kubanka (T. durum) carrying Ne1s and recombinant inbred lines or doubled haploid lines from three crosses segregating for Lr13. F1 plants from lines carrying Lr13 crossed with Spica (Ne1s) always showed progressive necrosis; those lacking Lr13 did not. Four wheat cultivars/lines carrying Lr13 were treated with the mutagen EMS. Thirty-five susceptible mutants were identified; eight were distinctly less glaucous and late maturing indicative of chromosome 2B or sub-chromosome loss. Hybrids of phenotypically normal Lr13 mutant plants crossed with Spica did not produce symptoms of hybrid necrosis. Thus, Lr13 and one particular Ne2m allele may be the same gene.


Asunto(s)
Basidiomycota/patogenicidad , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/genética , Triticum/genética , Alelos , Mapeo Cromosómico , Cruzamientos Genéticos , Genes Dominantes , Genes de Plantas , Marcadores Genéticos , Genotipo , Enfermedades de las Plantas/microbiología , Hojas de la Planta/microbiología , Triticum/microbiología
16.
PLoS One ; 9(10): e109466, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25310300

RESUMEN

The gastric pathogen Helicobacter pylori is one of the most genetically diverse of bacterial species. Much of its diversity stems from frequent mutation and recombination, preferential transmission within families and local communities, and selection during persistent gastric mucosal infection. MLST of seven housekeeping genes had identified multiple distinct H. pylori populations, including three from Africa: hpNEAfrica, hpAfrica1 and hpAfrica2, which consists of three subpopulations (hspWAfrica, hspCAfrica and hspSAfrica). Most detailed H. pylori population analyses have used strains from non-African countries, despite Africa's high importance in the emergence and evolution of humans and their pathogens. Our concatenated sequences from seven H. pylori housekeeping genes from 44 Gambian patients (MLST) identified 42 distinct sequence types (or haplotypes), and no clustering with age or disease. STRUCTURE analysis of the sequence data indicated that Gambian H. pylori strains belong to the hspWAfrica subpopulation of hpAfrica1, in accord with Gambia's West African location. Despite Gambia's history of invasion and colonisation by Europeans and North Africans during the last millennium, no traces of Ancestral Europe1 (AE1) population carried by those people were found. Instead, admixture of 17% from Ancestral Europe2 (AE2) was detected in Gambian strains; this population predominates in Nilo-Saharan speakers of North-East Africa, and might have been derived from admixture of hpNEAfrica strains these people carried when they migrated across the Sahara during the Holocene humid period 6,000-9,000 years ago. Alternatively, shared AE2 ancestry might have resulted from shared ancestral polymorphisms already present in the common ancestor of sister populations hpAfrica1 and hpNEAfrica.


Asunto(s)
Variación Genética , Helicobacter pylori/genética , Adolescente , Adulto , Anciano , Evolución Biológica , Niño , Preescolar , Femenino , Gambia , Mucosa Gástrica/microbiología , Genes Bacterianos , Genes Esenciales , Haplotipos , Infecciones por Helicobacter/etnología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/clasificación , Helicobacter pylori/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Tipificación de Secuencias Multilocus , Adulto Joven
17.
Theor Appl Genet ; 127(9): 2005-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25112203

RESUMEN

KEY MESSAGE: KU3198 is a common wheat accession that carries one novel leaf rust resistance (Lr) gene, Lr70 , and another Lr gene which is either novel, Lr52 or an allele of Lr52. Leaf rust, caused by Puccinia triticina Eriks. (Pt), is a broadly distributed and economically important disease of wheat. Deploying cultivars carrying effective leaf rust resistance (Lr) genes is a desirable method of disease control. KU3198 is a common wheat (Triticum aestivum L.) accession from the Kyoto collection that was highly resistant to Pt in Canada. An F2 population from the cross HY644/KU3198 showed segregation for two dominant Lr genes when tested with Pt race MBDS which was virulent on HY644. Multiple bulk segregant analysis (MBSA) was employed to find putative chromosome locations of these Lr genes using SSR markers that provided coverage of the genome. MBSA predicted that the Lr genes were located on chromosomes 5B and 5D. A doubled haploid population was generated from the cross of JBT05-714 (HY644*3/KU3198), a line carrying one of the Lr genes from KU3198, to Thatcher. This population segregated for a single Lr gene conferring resistance to Pt race MBDS, which was mapped to the terminal region of the short arm of chromosome 5B with SSR markers and given the temporary designation LrK1. One F3 family derived from the HY644/KU3198 F2 population that segregated only for the second Lr gene from KU3198 was identified. This family was treated as an F2-equivalent population and used for mapping the Lr gene, which was located to the terminal region of chromosome 5DS. As no other Lr gene has been mapped to 5DS, this gene is novel and has been designated as Lr70.


Asunto(s)
Basidiomycota/patogenicidad , Resistencia a la Enfermedad/genética , Genes de Plantas , Enfermedades de las Plantas/genética , Triticum/genética , Mapeo Cromosómico , Cruzamientos Genéticos , ADN de Plantas/genética , Marcadores Genéticos , Repeticiones de Microsatélite , Análisis de Secuencia de ADN
18.
BMC Infect Dis ; 13: 422, 2013 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-24010891

RESUMEN

BACKGROUND: Helicobacter pylori infection is acquired in early childhood and persists for life (or until eradication treatment is taken). Seropositivity of H. pylori at age 49-51 years was assessed in relation to socio-economic deprivation in early life and the timing of other childhood infections common at that time. METHODS: Prospectively collected socio-economic and morbidity data from the Newcastle Thousand Families study, a birth cohort established in 1947. H. pylori IgG seropositivity was assessed at 49-51 years and examined in relation to both whether the individual had been diagnosed with one of measles, mumps or chicken pox, and, if so, the age at first infection. This was done in logistic regression models, allowing adjustment for socio-economic status and housing quality in childhood. RESULTS: Adult H. pylori status was strongly linked to disadvantaged socio-economic status in early life (p ≤ 0.002), unlike measles, mumps and chicken pox which showed no associations. Early measles infection was independently associated with H. pylori seropositivity (p = 0.01). CONCLUSIONS: Of the four infectious diseases that we have studied, it appears that H. pylori differs from the others by the strength of association with socio economic deprivation in early childhood. Our findings further highlight the complex interaction between measles, childhood infections and other non-microbiological factors that occur within a whole population. These data suggest a strong association between H. pylori and deprivation and raise the possibility of an interaction between early measles exposure and increased risk of exposure to H. pylori infection.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Infecciones por Helicobacter/inmunología , Helicobacter pylori/inmunología , Preescolar , Estudios de Cohortes , Femenino , Infecciones por Helicobacter/economía , Infecciones por Helicobacter/epidemiología , Infecciones por Helicobacter/etiología , Humanos , Masculino , Sarampión/complicaciones , Persona de Mediana Edad , Factores de Riesgo , Factores Socioeconómicos , Reino Unido/epidemiología
19.
Eur J Epidemiol ; 28(3): 257-65, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23412929

RESUMEN

Studies of the association between early life infections and cancer have produced inconsistent findings, possibly due to limited adjustment for confounding and retrospective designs. This study utilised data from the Newcastle Thousand Families Study, a prospective cohort of 1,142 individuals born in Newcastle-upon-Tyne in 1947, to assess the impact of various childhood infectious diseases on cancer mortality during ages 15-60 years. Detailed information was collected prospectively on a number of early life factors. Deaths from cancer during ages 15-60 years were analysed in relation to childhood infections, adjusting for potential early-life confounders, using Cox proportional-hazards regression. In a subsample who returned questionnaires at aged 49-51 years, additional adjustment was made for adult factors to predict death from cancer during ages 50-60 years. Childhood history of measles and influenza, were both independently associated with lower cancer mortality during ages 15-60 years (adjusted hazard ratios = 0.39, 95% CI 0.17-0.88 and 0.49, 95% CI 0.24-0.98 respectively). In contrast, childhood pertussis was associated with higher cancer mortality during ages 15-60 years (adjusted hazard ratio = 4.88, 95% CI 2.29-10.38). In the subsample with additional adjustment for adult variables, measles and pertussis remained significantly associated with cancer mortality during ages 50-60 years. In this pre-vaccination cohort, childhood infection with measles and influenza were associated with a reduced risk of death from cancer in adulthood, while pertussis was associated with an increased risk. While these results suggest some disease-specific associations between early-life infections and cancer, further studies are required to confirm the specific associations identified.


Asunto(s)
Envejecimiento/inmunología , Enfermedades Transmisibles/epidemiología , Mortalidad Prematura , Neoplasias/epidemiología , Adolescente , Adulto , Distribución por Edad , Factores de Edad , Enfermedades Transmisibles/complicaciones , Femenino , Estudios de Seguimiento , Humanos , Gripe Humana/mortalidad , Masculino , Sarampión/mortalidad , Persona de Mediana Edad , Neoplasias/etiología , Oportunidad Relativa , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de Riesgo , Factores Socioeconómicos , Encuestas y Cuestionarios , Reino Unido/epidemiología , Tos Ferina/mortalidad , Adulto Joven
20.
Theor Appl Genet ; 126(2): 443-9, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23052026

RESUMEN

An important aspect of studying putative new genes in wheat is determining their position on the wheat genetic map. The primary difficulty in mapping genes is determining which chromosome carries the gene of interest. Several approaches have been developed to address this problem, each with advantages and disadvantages. Here we describe a new approach called multiple bulked segregant analysis (MBSA). A set of 423 simple sequence repeat (SSR) markers were selected based on profile simplicity, frequency of polymorphism, and distribution across the wheat genome. SSR primers were preloaded in 384-well PCR plates with each primer occupying 16 wells. In practice, 14 wells are reserved for "mini-bulks" that are equivalent to four gametes (e.g. two F(2) individuals) comprised of individuals from a segregated population that have a known homozygous genotype for the gene of interest. The remaining two wells are reserved for the parents of the population. Each well containing a mini-bulk can have one of three allele compositions for each SSR: only the allele from one parent, only the allele from the other parent, or both alleles. Simulation experiments were performed to determine the pattern of mini-bulk allele composition that would indicate putative linkage between the SSR in question and the gene of interest. As a test case, MBSA was employed to locate an unidentified stem rust resistance (Sr) gene in the winter wheat cultivar Norin 40. A doubled haploid (DH) population (n = 267) was produced from hybrids of the cross LMPG-6S/Norin 40. The DH population segregated for a single gene (χ (1:1) (2) = 0.093, p = 0.76) for resistance to Puccinia graminis f.sp. tritici race LCBN. Four resistant DH lines were included in each of the 14 mini-bulks for screening. The Sr gene was successfully located to the long arm of chromosome 2D using MBSA. Further mapping confirmed the chromosome location and revealed that the Sr gene was located in a linkage block that may represent an alien translocation. The new Sr gene was designated as Sr54.


Asunto(s)
Basidiomycota/fisiología , Segregación Cromosómica , Resistencia a la Enfermedad/genética , Genes de Plantas/genética , Enfermedades de las Plantas/microbiología , Tallos de la Planta/genética , Triticum/genética , Basidiomycota/patogenicidad , Mapeo Cromosómico , Cromosomas de las Plantas/genética , Regulación de la Expresión Génica de las Plantas , Marcadores Genéticos , Inmunidad Innata , Repeticiones de Microsatélite/genética , Microscopía Electrónica de Transmisión de Rastreo , Fenotipo , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Tallos de la Planta/inmunología , Tallos de la Planta/microbiología , Estaciones del Año , Triticum/inmunología , Triticum/microbiología
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