1,322 research outputs found

    Verified and potential pathogens of predatory mites (Acari: Phytoseiidae)

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    Several species of phytoseiid mites (Acari: Phytoseiidae), including species of the genera Amblyseius, Galendromus, Metaseiulus, Neoseiulus, Phytoseiulus and Typhlodromus, are currently reared for biological control of various crop pests and/or as model organisms for the study of predator¿prey interactions. Pathogen-free phytoseiid mites are important to obtain high efficacy in biological pest control and to get reliable data in mite research, as pathogens may affect the performance of their host or alter their reproduction and behaviour. Potential and verified pathogens have been reported for phytoseiid mites during the past 25 years. The present review provides an overview, including potential pathogens with unknown host effects (17 reports), endosymbiotic Wolbachia (seven reports), other bacteria (including Cardinium and Spiroplasma) (four reports), cases of unidentified diseases (three reports) and cases of verified pathogens (six reports). From the latter group four reports refer to Microsporidia, one to a fungus and one to a bacterium. Only five entities have been studied in detail, including Wolbachia infecting seven predatory mite species, other endosymbiotic bacteria infecting Metaseiulus (Galendromus, Typhlodromus) occidentalis (Nesbitt), the bacterium Acaricomes phytoseiuli infecting Phytoseiulus persimilis Athias-Henriot, the microsporidium Microsporidium phytoseiuli infecting P. persimilis and the microsporidium Oligosproridium occidentalis infecting M. occidentalis. In four cases (Wolbachia, A. phytoseiuli, M. phytoseiuli and O. occidentalis) an infection may be connected with fitness costs of the host. Moreover, infection is not always readily visible as no obvious gross symptoms are present. Monitoring of these entities on a routine and continuous basis should therefore get more attention, especially in commercial mass-production. Special attention should be paid to field-collected mites before introduction into the laboratory or mass rearing, and to mites that are exchanged among rearing facilities. However, at present general pathogen monitoring is not yet practical as effects of many entities are unknown. More research effort is needed concerning verified and potential pathogens of commercially reared arthropods and those used as model organisms in research

    Managing lifestyle change to reduce coronary risk: a synthesis of qualitative research on peoples’ experiences

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    Background Coronary heart disease is an incurable condition. The only approach known to slow its progression is healthy lifestyle change and concordance with cardio-protective medicines. Few people fully succeed in these daily activities so potential health improvements are not fully realised. Little is known about peoples’ experiences of managing lifestyle change. The aim of this study was to synthesise qualitative research to explain how participants make lifestyle change after a cardiac event and explore this within the wider illness experience. Methods A qualitative synthesis was conducted drawing upon the principles of meta-ethnography. Qualitative studies were identified through a systematic search of 7 databases using explicit criteria. Key concepts were identified and translated across studies. Findings were discussed and diagrammed during a series of audiotaped meetings. Results The final synthesis is grounded in findings from 27 studies, with over 500 participants (56% male) across 8 countries. All participants experienced a change in their self-identity from what was ‘familiar’ to ‘unfamiliar’. The transition process involved ‘finding new limits and a life worth living’ , ‘finding support for self’ and ‘finding a new normal’. Analyses of these concepts led to the generation of a third order construct, namely an ongoing process of ‘reassessing past, present and future lives’ as participants considered their changed identity. Participants experienced a strong urge to get back to ‘normal’. Support from family and friends could enable or constrain life change and lifestyle changes. Lifestyle change was but one small part of a wider ‘life’ change that occurred. Conclusions The final synthesis presents an interpretation, not evident in the primary studies, of a person-centred model to explain how lifestyle change is situated within ‘wider’ life changes. The magnitude of individual responses to a changed health status varied. Participants experienced distress as their notion of self identity shifted and emotions that reflected the various stages of the grief process were evident in participants’ accounts. The process of self-managing lifestyle took place through experiential learning; the level of engagement with lifestyle change reflected an individual’s unique view of the balance needed to manage ‘realistic change’ whilst leading to a life that was perceived as ‘worth living’. Findings highlight the importance of providing person centred care that aligns with both psychological and physical dimensions of recovery which are inextricably linked

    Influence of Efforts of Employer and Employee on Return-to-Work Process and Outcomes

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    Background Research on disability and RTW outcome has led to significant advances in understanding these outcomes, however, limited studies focus on measuring the RTW process. After a prolonged period of sickness absence, the assessment of the RTW process by investigating RTW Effort Sufficiency (RTW-ES) is essential. However, little is known about factors influencing RTW-ES. Also, the correspondence in factors determining RTW-ES and RTW is unknown. The purpose of this study was to investigate 1) the strength and relevance of factors related to RTW-ES and RTW (no/partial RTW), and 2) the comparability of factors associated with RTW-ES and with RTW. Methods During 4 months, all assessments of RTW-ES and RTW (no/partial RTW) among employees applying for disability benefits after 2 years of sickness absence, performed by labor experts at 3 Dutch Social Insurance Institute locations, were investigated by means of a questionnaire. Results Questionnaires concerning 415 cases were available. Using multiple logistic regression analysis, the only factor related to RTW-ES is a good employer-employee relationship. Factors related to RTW (no/partial RTW) were found to be high education, no previous periods of complete disability and a good employer-employee relationship. Conclusions Different factors are relevant to RTW-ES and RTW, but the employer-employee relationship is relevant for both. Considering the importance of the assessment of RTW-ES after a prolonged period of sickness absence among employees who are not fully disabled, this knowledge is essential for the assessment of RTW-ES and the RTW process itself

    DUOX1 mediates persistent epithelial EGFR activation, mucous cell metaplasia, and airway remodeling during allergic asthma

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    Chronic inflammation with mucous metaplasia and airway remodeling are hallmarks of allergic asthma, and these outcomes have been associated with enhanced expression and activation of EGFR signaling. Here, we demonstrate enhanced expression of EGFR ligands such as amphiregulin as well as constitutive EGFR activation in cultured nasal epithelial cells from asthmatic subjects compared with nonasthmatic controls and in lung tissues of mice during house dust mite-induced (HDM-induced) allergic inflammation. EGFR activation was associated with cysteine oxidation within EGFR and the nonreceptor tyrosine kinase Src, and both amphiregulin production and oxidative EGFR activation were diminished by pharmacologic or genetic inhibition of the epithelial NADPH oxidase dual oxidase 1 (DUOX1). DUOX1 deficiency also attenuated several EGFR-dependent features of HDM-induced allergic airway inflammation, including neutrophilic inflammation, type 2 cytokine production (IL-33, IL-13), mucous metaplasia, subepithelial fibrosis, and central airway resistance. Moreover, targeted inhibition of airway DUOX1 in mice with previously established HDM-induced allergic inflammation, by intratracheal administration of DUOX1-targeted siRNA or pharmacological NADPH oxidase inhibitors, reversed most of these outcomes. Our findings indicate an important function for DUOX1 in allergic inflammation related to persistent EGFR activation and suggest that DUOX1 targeting may represent an attractive strategy in asthma management

    DUOX1 mediates persistent epithelial EGFR activation, mucous cell metaplasia, and airway remodeling during allergic asthma

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    Chronic inflammation with mucous metaplasia and airway remodeling are hallmarks of allergic asthma, and these outcomes have been associated with enhanced expression and activation of EGFR signaling. Here, we demonstrate enhanced expression of EGFR ligands such as amphiregulin as well as constitutive EGFR activation in cultured nasal epithelial cells from asthmatic subjects compared with nonasthmatic controls and in lung tissues of mice during house dust mite-induced (HDM-induced) allergic inflammation. EGFR activation was associated with cysteine oxidation within EGFR and the nonreceptor tyrosine kinase Src, and both amphiregulin production and oxidative EGFR activation were diminished by pharmacologic or genetic inhibition of the epithelial NADPH oxidase dual oxidase 1 (DUOX1). DUOX1 deficiency also attenuated several EGFR-dependent features of HDM-induced allergic airway inflammation, including neutrophilic inflammation, type 2 cytokine production (IL-33, IL-13), mucous metaplasia, subepithelial fibrosis, and central airway resistance. Moreover, targeted inhibition of airway DUOX1 in mice with previously established HDM-induced allergic inflammation, by intratracheal administration of DUOX1-targeted siRNA or pharmacological NADPH oxidase inhibitors, reversed most of these outcomes. Our findings indicate an important function for DUOX1 in allergic inflammation related to persistent EGFR activation and suggest that DUOX1 targeting may represent an attractive strategy in asthma management

    Autoimmune and autoinflammatory mechanisms in uveitis

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    The eye, as currently viewed, is neither immunologically ignorant nor sequestered from the systemic environment. The eye utilises distinct immunoregulatory mechanisms to preserve tissue and cellular function in the face of immune-mediated insult; clinically, inflammation following such an insult is termed uveitis. The intra-ocular inflammation in uveitis may be clinically obvious as a result of infection (e.g. toxoplasma, herpes), but in the main infection, if any, remains covert. We now recognise that healthy tissues including the retina have regulatory mechanisms imparted by control of myeloid cells through receptors (e.g. CD200R) and soluble inhibitory factors (e.g. alpha-MSH), regulation of the blood retinal barrier, and active immune surveillance. Once homoeostasis has been disrupted and inflammation ensues, the mechanisms to regulate inflammation, including T cell apoptosis, generation of Treg cells, and myeloid cell suppression in situ, are less successful. Why inflammation becomes persistent remains unknown, but extrapolating from animal models, possibilities include differential trafficking of T cells from the retina, residency of CD8(+) T cells, and alterations of myeloid cell phenotype and function. Translating lessons learned from animal models to humans has been helped by system biology approaches and informatics, which suggest that diseased animals and people share similar changes in T cell phenotypes and monocyte function to date. Together the data infer a possible cryptic infectious drive in uveitis that unlocks and drives persistent autoimmune responses, or promotes further innate immune responses. Thus there may be many mechanisms in common with those observed in autoinflammatory disorders

    Obesity prevalence estimates in a Canadian regional population of preschool children using variant growth references

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    <p>Abstract</p> <p>Background</p> <p>Childhood obesity is a public health problem in Canada. Accurate measurement of a health problem is crucial in defining its burden. The objective of this study is to compare the prevalence estimates of overweight and obesity in preschool children using three growth references.</p> <p>Methods</p> <p>Weights and heights were measured on 1026 preschool children born in Newfoundland and Labrador (NL), Canada, and body mass index calculated. The prevalence of overweight and obesity was determined and statistical comparisons conducted among the three growth references; the Centres for Disease Control (CDC), the International Obesity Task Force (IOTF) and the World Health Organization (WHO).</p> <p>Results</p> <p>CDC and IOTF produced similar estimates of the prevalence of overweight, 19.1% versus 18.2% while the WHO reported a higher prevalence 26.7% (p < .001). The CDC classified twice as many children as obese compared to the IOTF 16.6% versus 8.3% (p < .001) and a third more than the WHO 16.6% versus 11.3% (p < .01). There was variable level of agreement between methods.</p> <p>Conclusions</p> <p>The CDC reported a much higher prevalence of obesity compared to the other references. The prevalence of childhood obesity is dependent on the growth reference used.</p

    Decreased surfactant phosphatidylcholine synthesis in neonates with congenital diaphragmatic hernia during extracorporeal membrane oxygenation

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    Purpose: Congenital diaphragmatic hernia (CDH) may result in severe respiratory insufficiency with a high morbidity. The role of a disturbed surfactant metabolism in the pathogenesis of CDH is unclear. We therefore studied endogenous surfactant metabolism in the most severe CDH patients who required extracorporeal membrane oxygenation (ECMO). Methods: Eleven neonates with CDH who required ECMO and ten ventilated neonates without significant lung disease received a 24-h infusion of the stable isotope [U-13C] glucose. The13C-incorporation into palmitic acid in surfactant phosphatidylcholine (PC) isolated from serial tracheal aspirates was measured. Mean PC concentration in epithelial lining fluid (ELF) was measured during the first 4 days of the study. Results: Fractional surfactant PC synthesis was decreased in CDH-ECMO patients compared to controls (2.4 ± 0.33 vs. 8.0 ± 2.4%/day, p = 0.04). The control group had a higher maximal enrichment (0.18 ± 0.03 vs. 0.09 ± 0.02 APE, p = 0.04) and reached this maximal enrichment earlier (46.7 ± 3.0 vs. 69.4 ± 6.6 h, p = 0.004) compared to the CDH-ECMO group, which reflects higher and faster precursor incorporation in the control group. Surfactant PC concentration in ELF was similar in both groups. Conclusion: These results show that CDH patients who require ECMO have a decreased surfactant PC synthesis, which may be part of the pathogenesis of severe pulmonary insufficiency and has a negative impact on weaning from ECMO
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