708 research outputs found

    Genetic diversity and origins of the homoploid type hybrid Phytophthora×alni

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    Assessing the process that gives rise to hybrid pathogens is central to understanding the evolution of emerging plant diseases. Phytophthora xalni, a pathogen of alder, results from the homoploid hybridization of two related species, Phytophthora uniformis and Phytophthora xmultiformis. Describing the genetic characteristics of P. xalni should help us understand how reproductive mechanisms and historical processes shaped the population structure of this emerging hybrid pathogen. The population genetic structure of P. xalni and the relationship with its parental species were investigated using 12 microsatellites and one mitochondrial DNA (mtDNA) marker on a European collection of 379 isolates. Populations of P. xalni were dominated by one multilocus genotype (MLG). The frequency of this dominant MLG increased after the disease emergence together with a decline in diversity, suggesting that it was favored by a genetic mechanism such as drift or selection. Combined microsatellite and mtDNA results confirmed that P. xalni originated from multiple hybridization events that involved different genotypes of the progenitors. Our detailed analyses point to a geographic structure that mirrors that observed for P. uniformis in Europe. The study provides more insights on the contribution of P. uniformis, an invasive species in Europe, to the emergence of Phytophthora-induced alder decline. IMPORTANCE Our study describes an original approach to assess the population genetics of polyploid organisms using microsatellite markers. By studying the parental subgenomes present in the interspecific hybrid P. xalni, we were able to assess the geographical and temporal structure of European populations of the hybrid, shedding new light on the evolution of an emerging plant pathogen. In turn, the study of the parental subgenomes permitted us to assess some genetic characteristics of the parental species of P. xalni, P. uniformis, and P. xmultiformis, which are seldom sampled in nature. The subgenomes found in P. xalni represent a picture of the "fossilized" diversity of the parental species

    Evaluation of a psychoeducational intervention for adolescents with inflammatory bowel disease

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    OBJECTIVES: Inflammatory bowel disease (IBD), comprising Crohn's disease, ulcerative colitis, and indeterminate colitis, often has its onset in adolescence. The aim of this study was to evaluate whether a psychoeducational group intervention (aiming to enhance information seeking and giving about the disease, relaxation, social competence, and positive thinking) can strengthen the coping efforts of adolescents with IBD and have a positive effect on their Health-Related Quality of Life (HRQoL). METHODS: Adolescent IBD patients from the Emma Children's Hospital AMC and adolescent members of the Crohn and Ulcerative Colitis Association in The Netherlands, were invited to participate in The intervention study. Using reliable and valid self-report instruments the adolescent's coping styles, feelings of competence, and HRQoL were assessed before and 6-8 months after the intervention. The parents were asked to fill in the Child Behavior Check List. Linear regression analyses were performed to test whether group participation was predictive of the outcome measures while correcting for the first measurement occasion and sex. RESULTS AND CONCLUSION: Forty patients responded positively to invitation to the intervention. Eighteen adolescents, however, lived too far away to attend and served as a control group. Twenty-two children were enrolled and attended in groups of four to six children in six group sessions, supervised by two psychologists. The intervention seemed to have a positive effect on: coping (predictive control, P<0.01), feelings of competence (global self-worth, P<0.05 and physical appearance, P<0.01), and HRQoL (body image, P<0.05). These results give good reason to continue this intervention study with a larger population. © 2009 Lippincott Williams & Wilkins, Inc

    Systematic review: psychological morbidity in young people with inflammatory bowel disease - risk factors and impacts

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    BACKGROUND: Psychological morbidity in young people aged 10-24 years, with inflammatory bowel disease (IBD) is increased, but risk factors for and impacts of this are unclear. AIM: To undertake a systematic literature review of the risk factors for and impact of psychological morbidity in young people with IBD. METHODS: Electronic searches for English-language articles were performed with keywords relating to psychological morbidity according to DSM-IV and subsequent criteria; young people; and IBD in the MEDLINE, PsychInfo, Web of Science and CINAHL databases for studies published from 1994 to September 2014. RESULTS: One thousand four hundred and forty-four studies were identified, of which 30 met the inclusion criteria. The majority measured depression and anxiety symptoms, with a small proportion examining externalising behaviours. Identifiable risk factors for psychological morbidity included: increased disease severity (r(2) = 0.152, P < 0.001), lower socioeconomic status (r(2) = 0.046, P < 0.001), corticosteroids (P ≤ 0.001), parental stress (r = 0.35, P < 0.001) and older age at diagnosis (r = 0.28, P = 0.0006). Impacts of psychological morbidity in young people with IBD were wide-ranging and included abdominal pain (r = 0.33; P < 0.001), sleep dysfunction (P < 0.05), psychotropic drug use (HR 4.16, 95% CI 2.76-6.27), non-adherence to medication (12.6% reduction) and negative illness perceptions (r = -0.43). CONCLUSIONS: Psychological morbidity affects young people with IBD in a range of ways, highlighting the need for psychological interventions to improve outcomes. Identified risk factors provide an opportunity to develop targeted therapies for a vulnerable group. Further research is required to examine groups under-represented in this review, such as those with severe IBD and those from ethnic minorities

    UK guideline on transition of adolescent and young persons with chronic digestive diseases from paediatric to adult care

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    The risks of poor transition include delayed and inappropriate transfer that can result in disengagement with healthcare. Structured transition care can improve control of chronic digestive diseases and long-term health-related outcomes. These are the first nationally developed guidelines on the transition of adolescent and young persons (AYP) with chronic digestive diseases from paediatric to adult care. They were commissioned by the Clinical Services and Standards Committee of the British Society of Gastroenterology under the auspices of the Adolescent and Young Persons (A&YP) Section. Electronic searches for English-language articles were performed with keywords relating to digestive system diseases and transition to adult care in the Medline (via Ovid), PsycInfo (via Ovid), Web of Science and CINAHL databases for studies published from 1980 to September 2014. The quality of evidence and grading of recommendations was appraised using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. The limited number of studies in gastroenterology and hepatology required the addition of relevant studies from other chronic diseases to be included. These guidelines deal specifically with the transition of AYP living with a diagnosis of chronic digestive disease and/or liver disease from paediatric to adult healthcare under the following headings; 1. Patient populations involved in AYP transition 2. Risks of failing transition or poor transition 3. Models of AYP transition 4. Patient and carer/parent perspective in AYP transition 5. Surgical perspectiv

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