Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
1.
Planta ; 254(2): 40, 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34324072

RESUMO

MAIN CONCLUSION: Non-canonical AUX/IAA protein, OsIAA29, and ZmMPR-1 homologues, OsMRPLs, are part of an auxin-related signalling cascade operating in the dorsal aleurone during early rice grain development. Endosperm of rice and other cereals accumulates high concentrations of the predominant in planta auxin, indole-3-acetic acid (IAA) during early grain development. However, IAA signalling and function during endosperm development are poorly understood. Here, we report that OsYUC12 (an auxin biosynthesis gene) and OsIAA29 (encoding a non-canonical AUX/IAA) are both expressed exclusively in grains, reaching a maximum 5-6 days after pollination. OsYUC12 expression is localised in the aleurone, sub-aleurone and embryo, whereas OsIAA29 expression is restricted to a narrow strip in the dorsal aleurone, directly under the vascular bundle. Although rice has been reported to lack endosperm transfer cells (ETCs), this region of the aleurone is enriched with sugar transporters and is likely to play a key role in apoplastic nutrient transfer, analogous to ETCs in other cereals. OsIAA29 has orthologues only in grass species; expression of which is also specific to early grain development. OsYUC12 and OsIAA29 are temporally co-expressed with two genes (AL1 and OsPR602) previously linked to the development of dorsal aleurone or ETCs. Also up-regulated at the same time is a cluster of MYB-related genes (designated OsMRPLs) homologous to ZmMRP-1, which regulates maize ETC development. Wheat homologues of ZmMRP-1 are similarly expressed in ETCs. Although previous work has suggested that other cereals do not have orthologues of ZmMRP-1, our work suggests OsIAA29 and OsMRPLs and their homologues in other grasses are part of an auxin-regulated, conserved signalling network involved in the differentiation of cells with ETC-like function in developing cereal grains.


Assuntos
Oryza , Endosperma/genética , Endosperma/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
Psychooncology ; 27(1): 223-228, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28692205

RESUMO

OBJECTIVE: To investigate the effect of chronic stress as measured in cortisol concentrations upon the association between psychological resilience (PR) and depression in prostate cancer (PCa) patients. METHODS: A total of 104 men with PCa completed inventories on PR, depression, and background factors, plus gave a sample of their saliva for cortisol assay. RESULTS: The inverse correlation between PR and depression was present only for PCa patients with low or moderate concentrations of salivary cortisol (when classified as more than 1.0 SD below the mean vs within 1.0 SD of the group mean) but not for those men whose cortisol was >1.0 SD from the group mean. Specific PR factors and behaviours that made the greatest contribution to depression were identified for the low and moderate cortisol groups. CONCLUSIONS: These results suggest that there are particular aspects of PR that are most strongly related to depression, but that PR's inverse association with depression may be absent in participants with extreme chronic physiological stress.


Assuntos
Depressão/psicologia , Neoplasias da Próstata/psicologia , Resiliência Psicológica , Estresse Fisiológico , Estresse Psicológico/psicologia , Adulto , Idoso , Transtorno Depressivo , Feminino , Humanos , Hidrocortisona/metabolismo , Masculino , Pessoa de Meia-Idade , Saliva
3.
Support Care Cancer ; 26(9): 3195-3200, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29603029

RESUMO

PURPOSE: Some prostate cancer (PCa) patients become clinically anxious or depressed after diagnosis and treatment. Some also show the physiological signs of chronic stress. However, there are currently no data describing how these particular patients might be identified at intake. This study tested the individual and combined predictive power of a psychological factor and a genetic factor as potential predictors of anxiety, depression, and chronic stress in a sample of PCa patients. METHODS: Ninety-five PCa patients completed psychological inventories for anxiety, depression, and psychological resilience (PR) and also gave a saliva sample for cortisol and a mouthwash sample for genetic testing for the presence of the BDNF Val66Met polymorphism. RESULTS: High PR patients had significantly lower anxiety and depression than low PR patients, but showed no significant differences in their salivary cortisol. Carriers of the Met allele of the BDNF Val66Met polymorphism had significantly higher salivary cortisol concentrations than patients who did not carry this allele. CONCLUSIONS: Each of these two factors may provide valuable information regarding the vulnerability of PCa patients to anxiety, depression, or chronic stress. Suggestions are made for their inclusion in clinical settings.


Assuntos
Ansiedade/genética , Depressão/psicologia , Neoplasias da Próstata/psicologia , Estresse Psicológico/psicologia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/patologia
4.
Reprod Fertil Dev ; 26(5): 633-44, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23673210

RESUMO

Adhesion molecules are expressed by both adult and embryonic stem cells, with different classes of adhesion molecules involved in cell-membrane and intercellular contacts. In this study the expression of the adhesion molecule claudin-8 (CLDN8), a tight-junction protein, was investigated as a potential marker for undifferentiated spermatogonia in the bovine testis. We found that CLDN8 was expressed by both spermatogonia and a subset of Sertoli cells in the bovine testis. We also showed co-expression of GFRα1 in testis cells with CLDN8 and with Dolichos biflorus agglutinin-fluorescein isothiocyanate (DBA-FITC) staining. We observed co-enrichment of spermatogonia and CLDN8-expressing Sertoli cells in DBA-FITC-assisted magnetic-activated cell sorting (MACS), an observation supported by results from fluorescence-activated cell sorting analysis, which showed CLDN8-expressing cells were over-represented in the MACS-positive cell fraction, leading to the hypothesis that CLDN8 may play a role in the spermatogonial stem-cell niche.


Assuntos
Células-Tronco Adultas/metabolismo , Claudinas/metabolismo , Células de Sertoli/metabolismo , Testículo/citologia , Células-Tronco Adultas/citologia , Animais , Bovinos , Separação Celular , Citometria de Fluxo , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Masculino , Células de Sertoli/citologia , Nicho de Células-Tronco/fisiologia , Testículo/metabolismo
6.
J Microbiol Biol Educ ; 24(3)2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38107992

RESUMO

Travel restrictions, pandemics, economic downturn, and increasing costs in organizing workshops all impact on face-to-face training of undergraduates planning to undertake research. The inability to obtain basic, first-hand information regarding research in practice causes undue stress for students and leads to unrealistic expectations regarding research projects. Here, we describe how a student initiated online workshop, co-designed by a group of undergraduate leaders in conjunction with a panel of international academic researchers, and enabled the delivery of an introductory workshop on research training to meet student needs. Post-workshop, over 80%-95% of the participants rated their understanding of different aspects of research in practice as either being good or excellent. The design of this workshop provides an innovative template, in particular for resource-restricted countries, on how student-initiated workshops with multi-institutional academic collaboration could enhance training in research practice.

8.
Health Soc Care Community ; 30(2): 448-468, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34423491

RESUMO

Housing is a significant determinant of health and is widely accepted as a key solution to address some of the health disparities that exist among the homeless. It is estimated that 150 million people worldwide are homeless, and approximately 1.8 billion lack adequate housing. However, understanding of how housing has a positive impact on the health of the homeless remains unclear and underdeveloped. This systematic review investigates intervention studies that report on the physical and mental health effects of housing homeless persons. A search of PubMed, PsycINFO, EBSCOHost-Academic Search Complete and the Cochrane Library was conducted for peer-reviewed articles published in English from 1999 to 2020 that had a combination of at least one housing intervention and health outcome, with a homeless sample. Three previous reviews and 24 studies were included for analysis. Most of the studies (n = 20) encompassed permanent supportive housing interventions that emphasised placing homeless people with mental illness directly into affordable housing with access to support services. The primary health outcomes reported were general physical and mental health, well-being, and quality of life. Despite inconsistent findings and significant issues identified in the reviewed literature, housing (in the short term) improves some aspects of health in homeless populations with human immunodeficiency virus, anxiety and depression.


Assuntos
Pessoas Mal Alojadas , Transtornos Mentais , Pessoas Mal Alojadas/psicologia , Habitação , Humanos , Transtornos Mentais/epidemiologia , Saúde Mental , Qualidade de Vida
9.
Cureus ; 14(8): e27830, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36110479

RESUMO

Headaches have been studied and treated since nearly 7,000 BC because of their significant global impact. Current headache treatment modalities are various and have a wide variety of targets, but medications are the most common. Since conventional medical treatments have several side effects, alternative remedies such as osteopathic manipulative treatment (OMT) should be considered. OMT can assist in the management of various health conditions, such as low back pain, neck pain, and headaches. The purpose of this scoping review is to evaluate recent findings regarding the efficacy of OMT modalities in the management of headaches such as tension-type headaches (TTH) and migraines. This study was designed as a scoping review to gather evidence on the efficacy of OMT modalities in the management of headaches. Following PRISMA guidelines, four databases were used to search for articles published between 2010 and 2022 that reported the use of OMT and manual therapy for TTH and migraines. Databases used include Embase, PubMed, Medline, and Web of Science. The following keywords were used: treatment, therapy, Headache, migraine, craniosacral, muscle energy, myofascial release, trigger point, osteopathic, and manipulation. The initial search yielded 473 unique articles after removing duplicates. After screening based on the inclusion and exclusion criteria, and after further analysis, 15 articles were selected. Data reports of OMT and manual therapy efficacy and/or effectiveness in treating TTH and migraine were analyzed. Articles included were randomized control studies (13 of 15, 86.6%), one pilot study (one of 15, 6.7%), and one case series (one of 15, 6.7%), which were divided into TTH (nine of 15, 60%) and Migraine Headaches (six of 15, 40%). All articles reported significant headache improvement in at least one measurement. Of all treatments analyzed, single technique interventions (seven of 15, 47%) and multiple technique interventions (eight of 15, 53%) were identified. Among the techniques used, Myofascial Release was the most common (nine of 15, 60%). The articles presented provide evidence of the significant benefits of manual therapy. Because of the limitations of traditional medicine, OMT can be used either as an alternative or adjuvant therapy for headaches. Evidence suggests the positive impact it can provide on headache management, but the number of randomized control trials and population samples should be increased to support its recommendation. This demonstrates how different osteopathic techniques can provide therapeutic effects on TTH, MH, and potentially other types of headaches. A preference for myofascial release was observed, which can be due to the fast relief from the physiologic effect on tissue movement. This review study demonstrates the benefits OMT has on decreasing headache frequency, intensity, and duration in TTH and migraines. OMT has shown to be beneficial, especially for patients seeking alternative non-pharmaceutical and non-invasive treatments. Further studies are needed to evaluate the effects of different OMT techniques, and different combinations of treatments, on other types of headaches.

11.
Nurse Educ Today ; 105: 105023, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34198160

RESUMO

BACKGROUND: Interprofessional education initiatives can be used as effective means to influence students' perceptions of their own and others' roles and interactions as health professionals. There is a need to better understand how interprofessional education learning outcomes are appreciated by students. AIM: The aims of this study were to describe and compare evaluation feedback from students in undergraduate nursing and medicine programmes about the learning outcomes of an interprofessional education initiative. METHODS: A mixed methods pre-post-study design was used to collect data using evaluation questions about the initiative and two interprofessional learning outcomes: communication and teamwork. Ratings were analysed with a two-way repeated measures analysis of variance or a t-test. Written responses were analysed using a general inductive approach. RESULTS: Data from 30 nursing students and 12 medical students were analysed. A noteworthy finding was a significantly higher average rating for nursing students than medicine students before and after the session for the statement about valuing interprofessional learning. Three themes represented comments from both groups: positive experiences, relevance to practice, and learning design issues. DISCUSSION: Findings were interpreted to indicate that students from both programmes valued the learning outcomes session and was greater at the end of the session. Notably, the perceived value of interprofessional learning was higher for nursing students than medical students before and after the session. This finding may be related to the familiarity nursing students may have with the teaching methods used in the initiative. Further exploration of this finding is needed so educators can better understand how they can provide optimal learning experiences for all students who participate in interprofessional education. CONCLUSION: Nursing and medicine students appear to value the interprofessional learning outcomes in an undergraduate health professional initiative. However, differences between these two groups of students are an area for further exploration.


Assuntos
Bacharelado em Enfermagem , Estudantes de Medicina , Estudantes de Enfermagem , Humanos , Educação Interprofissional , Relações Interprofissionais , Aprendizagem
12.
Int J Dev Neurosci ; 81(6): 502-509, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33993555

RESUMO

Autism Spectrum Disorder and depression are often co-occurring in young people. However, despite the association between these two disorders, and the fact that females have a higher prevalence of depression than males in the general population, there is little reported evidence regarding the correlates of depression in young autistic females. Several physiological (age, menarche, HPA-axis responses), psychological (social anxiety), and environmental or genetic (mothers' depression) factors were tested for their contribution to depression severity in a sample of 53 autistic girls aged 6 yr to 17 yr. Depression scores were collected from the girls' self-ratings and also from the ratings their mothers gave them. Regression results indicated that girls' social anxiety, age, and mothers' depression were common significant contributors to both sets of depression scores, but with different effects. Autistic girls' self-reports of their depression were significantly associated with their HPA-axis responses but not with their menarche status. Implications for research and clinical settings are discussed.


Assuntos
Transtorno do Espectro Autista/complicações , Depressão/complicações , Fobia Social/complicações , Meio Social , Adolescente , Adulto , Transtorno do Espectro Autista/fisiopatologia , Transtorno do Espectro Autista/psicologia , Criança , Depressão/fisiopatologia , Depressão/psicologia , Feminino , Humanos , Hidrocortisona/análise , Mães/psicologia , Fobia Social/fisiopatologia , Fobia Social/psicologia , Saliva/química
13.
Front Psychiatry ; 12: 533722, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867491

RESUMO

In order to evaluate the effects of specific forms of childhood maltreatment (CM) upon adult C-reactive protein (CRP) concentrations, and to further describe the potentially confounding role that recent life stress and depression hold in that relationship, 221 participants from rural Australia (M age = 44yr, SD = 17.8yr) completed self-report questionnaires and provided a blood sample. There were no sex differences in any variables across the 91 males and 130 females, but depression status did confound the association between global CM and CRP. The specific aspect of CM was identified as physical and mental health abuse, and this was significantly associated with CRP level in participants with depressive symptoms and those without. There was no significant confound from recent life stressors. Results hold implications for the diagnosis of CM-related CRP elevation and (potentially) depression.

14.
Behav Brain Res ; 383: 112482, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-31972185

RESUMO

Although EEG connectivity data are often used to build models of the association between overt behavioural signs of Autism Spectrum Disorder (ASD) and underlying brain connectivity indices, use of a large number of possible connectivity methods across studies has produced a fairly inconsistent set of results regarding this association. To explore the level of agreement between results from five commonly-used EEG connectivity models (i.e., Coherence, Weighted Phased Lag Index- Debiased, Phase Locking Value, Phase Slope Index, Granger Causality), a sample of 41 young males with ASD provided EEG data under eyes-opened and eyes-closed conditions. There were relatively few statistically significant and/or meaningful correlations between the results obtained from the five connectivity methods, arguing for a re-estimation of the methodology used in such studies so that specific connectivity methods may be matched to particular research questions regarding the links between neural connectivity and overt behaviour within this population.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Eletroencefalografia/métodos , Processamento de Sinais Assistido por Computador , Adolescente , Criança , Sincronização de Fases em Eletroencefalografia , Humanos , Masculino , Vias Neurais
15.
Sci Total Environ ; 655: 158-167, 2019 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-30469061

RESUMO

Water shortage and soil degradation are common environmental stressors encountered in the Mediterranean area. We evaluated how different soil moisture levels, dependent on distance from drip irrigation points, impact on the biological, chemical and physical properties of citrus soil under organic and inorganic fertilization. We measured soil physicochemical properties, basal soil respiration, soil microbial biomass carbon, soil microbial community structure (phospholipid fatty acid assay), bacterial load (16S rRNA gene abundance), enzymatic activities (urease, dehydrogenase, ß-glucosidase and acid phosphatase) and abundance of microbial nitrogen cyclers (quantitative PCR). A field experiment was established in an orange orchard (Citrus sinensis) in southeast Spain and eighteen soil samples were taken from each plot to compare the impacts of soil moisture: near (wet, w) or away (dry, d) from drip-irrigation points, in plots with inorganic fertilizers under intensive ploughing (PI) or organic fertilization (OA). The results showed that changes in microbial properties and soil microbial indexes were strongly associated with soil moisture content under both organic and inorganic fertilization, and with organic carbon content. Soil moisture influenced soil aggregation, basal soil respiration, phosphatase activity, bacterial and fungal load (PLFAs) and the abundances of bacterial N cycling genes, including nifH (nitrogen fixation) nirS/K and nosZ genes (denitrification) and amoA-B (bacterial nitrification). The potential for N fixation and denitrification, two microbial processes that are crucial for determining the amount of N in the soil, were improved by increased soil moisture in the proximity of the drip irrigation. Soil OC and total N, which are higher under organic fertilization than under inorganic fertilization, were also shown to be highly correlated with the abundance of the N cycling genes. By controlling irrigation doses and applying organic amendments, it may be possible to increase the microbial abundance and function in soil and support greater fertility of soils.


Assuntos
Irrigação Agrícola/métodos , Citrus sinensis/crescimento & desenvolvimento , Ciclo do Nitrogênio , Agricultura Orgânica/métodos , Microbiologia do Solo , Solo/química , Biomassa , Fertilizantes/análise , Genes Bacterianos , Região do Mediterrâneo , Ciclo do Nitrogênio/genética , Estações do Ano , Espanha
16.
Neuropsychiatr Dis Treat ; 15: 2467-2475, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695383

RESUMO

PURPOSE: Hormonal and inflammatory factors have been suggested as potentially influencing depressive state and depressive symptoms, but rarely compared for their relative contribution to these states and to specific depressive symptoms. This study examined cortisol:C-reactive protein (CRP) ratio, plus cortisol and CRP separately, as correlates of global depression and fatigue-related depression. PATIENTS AND METHODS: One hundred and twenty-six community volunteers from rural Australia provided saliva and serum samples, and also completed a depression inventory. RESULTS: There was a significant correlation between cortisol:CRP ratio and depression-related fatigue, and this resolved to the effects of CRP rather than cortisol. Most of the variance in this association came from patients who were "depressed", and there were no significant gender associations. CONCLUSION: Inflammation, rather than HPA-axis activity, was associated with depression-related fatigue, supporting a model that places inflammation as a contributor to one of the major symptoms and predictors of depression. Individualization of therapy for depression-related fatigue in chronically stressed or physically ill patients might benefit from future research into cytokine therapy.

17.
Physiol Behav ; 211: 112669, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31479683

RESUMO

Although previous data indicate that dyadic coping is associated with Hypothalamic-Pituitary-Adrenal (HPA-axis and C-reactive protein (CRP) separately, no study has reported on the ratio between these two systems and dyadic coping, despite this index of physiological homeostasis being associated with physical health and depression. Forty-eight community volunteers who were either married (n = 36) or cohabiting (n = 12) provided saliva and serum samples, and also completed a dyadic coping inventory. There was a significant inverse correlation between cortisol:CRP ratio and dyadic coping, but only for married participants. One of the six dyadic coping items, related to being able to calmly discuss something within a dyad, was the key factor in the association between dyadic coping and cortisol:CRP ratio. These findings provide some initial support for the influence of the way that spouses interact to solve problems and the balance between their HPA and immune systems.


Assuntos
Adaptação Psicológica/fisiologia , Hidrocortisona/análise , Relações Interpessoais , Cônjuges/psicologia , Estresse Psicológico/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína C-Reativa/análise , Feminino , Humanos , Hidrocortisona/sangue , Sistema Hipotálamo-Hipofisário/fisiopatologia , Masculino , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal/fisiopatologia , Saliva/química , Estresse Psicológico/psicologia , Adulto Jovem
18.
Rev Neurosci ; 30(5): 497-510, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-30269108

RESUMO

Autism spectrum disorder (ASD) is a neurodevelopmental condition affecting about 1 in 100 children and is currently incurable. ASD represents a challenge to traditional methods of assessment and diagnosis, and it has been suggested that direct measures of brain activity and connectivity between brain regions during demanding tasks represents a potential pathway to building more accurate models of underlying brain function and ASD. One of the key behavioural diagnostic indicators of ASD consists of sensory features (SF), often characterised by over- or under-reactivity to environmental stimuli. SF are associated with behavioural difficulties that impede social and education success in these children as well as anxiety and depression. This review examines the previous literature on the measurement of EEG connectivity and SF observed in individuals with ASD.


Assuntos
Transtorno Autístico/fisiopatologia , Eletroencefalografia/métodos , Sensação , Adolescente , Criança , Excitabilidade Cortical , Eletroencefalografia/normas , Humanos
19.
Aust Vet J ; 97(9): 323-332, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31328258

RESUMO

Haemorrhagic enteritis virus (HEV) causes clinical haemorrhagic enteritis in young poults and/or subclinical immunosuppression which is often associated with colibacillosis. This disease is controlled with live vaccines worldwide, however, importation of HEV vaccines or cells that support HEV propagation are not permitted in Australia. A major experiment in isolators was conducted to test the safety and efficacy of a putative HEV vaccine. The study had a factorial design with four factors namely vaccination age (28 and 42 days of age), vaccine dose (0, 105 , 106 , 107 genomic copies of HEV vaccine), challenge with HEV (yes, no) and vaccination-challenge interval (7, 21 or 42 days). A total of 315 poults were used providing 6-8 birds per treatment combination. Turkey growth rate, mortality, pathological findings, anti-HEV antibodies and viral load were examined. Vaccination lead to significant increases in anti HEV antibody over the following 2-4 weeks. Overall, vaccination with 106 and 107 was protective against increase in relative splenic weight and splenic viral load in challenged birds. Clinical haemorrhagic enteritis was not induced by any treatment but there was an increased incidence of airsacculitis in groups receiving either HEV vaccine or challenge virus compared to the negative control birds (25.8-29.3% vs. 9.4%, P < 0.05). Growth rate, mortality and relative bursal weight were unaffected by vaccination. This laboratory level study indicates that the putative vaccine is safe and likely to be efficacious, but may cause elevated levels of airsacculitis. These findings require confirmation in larger scale field trials.


Assuntos
Enterite/veterinária , Doenças das Aves Domésticas/imunologia , Perus , Vacinas Virais/farmacologia , Análise de Variância , Animais , Anticorpos Antivirais , Autopsia/veterinária , Enterite/imunologia , Enterite/prevenção & controle , Feminino , New South Wales , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/virologia
20.
Avian Dis ; 63(1): 84-89, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31251523

RESUMO

This study aimed to investigate the feasibility of propagating and titrating hemorrhagic enteritis virus (HEV) in chicken embryos. A total of 308 embryonated eggs were used. At 10 days of embryonic age, eggs were inoculated via allantoic sac or chorioallantoic membrane routes with non-heat-treated (live) HEV or heat-treated (dead) HEV or served as negative controls. Allantoic fluid retrieved at 0, 1, 3, 5, and 7 days postinoculation (dpi) was tested for HEV by quantitative PCR. Inoculation with HEV did not cause visible growth impairment or lesions in the chicken embryos. Overall, there was no difference in postinoculation mortality rates among groups sham-inoculated (6/30, 20.0%) or inoculated with live (34/252, 13.4%) or dead (3/ 26, 6.9%) HEV (P = 0.58). The amount of HEV DNA detected in allantoic fluid at 7 dpi in eggs inoculated with live virus was similar to the inoculated dose, indicating that virus propagation in chicken embryos is not efficient. No HEV DNA was detected after 3 dpi in eggs inoculated with dead virus. Inoculation of chicken embryos combined with qualitative PCR can be used for titration of HEV virus stocks and presents a high correlation with in vivo titration using chickens (R2 0.98, P = 0.007). This method may be relevant in countries in which specific-pathogen-free turkeys are unavailable and in which the importation of RP19 cells, the only cell that supports effective propagation of HEV, is not permitted.


El virus de la enteritis hemorrágica de los pavos puede ser titulado pero no propagado en embriones de pollo. Este estudio tuvo como objetivo investigar la viabilidad de propagar y titular al virus de la enteritis hemorrágica de los pavos (con las siglas en inglés HEV) en embriones de pollo. Se utilizaron un total de 308 huevos embrionados. A los 10 días de edad embrionaria, los huevos se inocularon por vía saco alantoideo o por la membrana corioalantoidea con el virus de la enteritis hemorrágica sin tratamiento térmico (vivo) o con un virus de la enteritis hemorrágica con tratamiento térmico (muerto) y algunos sirvieron como controles negativos. El fluido alantoideo recuperado a los cero, uno, tres, cinco y siete días después de la inoculación se analizó para detectar el VHE mediante un método cuantitativo de PCR. La inoculación con el virus de la enteritis hemorrágica no causó daños visibles en el crecimiento ni lesiones en los embriones de pollo. En general, no hubo diferencias en las tasas de mortalidad después de la inoculación entre los grupos con inoculación simulada (6/30, 20.0%) o inoculados con el virus vivo de la enteritis hemorrágica (34/252, 13.4%) o con el virus muerto (3/26, 6.9%) (P=0.58). La cantidad de ADN del virus fue detectada en el fluido alantoideo a los siete días después de la inoculación en huevos inoculados con virus vivos fue similar a la dosis inoculada, lo que indica que la propagación del virus en embriones de pollo no fue eficiente. No se detectó ADN del virus de la enteritis hemorrágica después de tres días después de la inoculación en huevos inoculados con virus muerto. La inoculación de embriones de pollo combinada con el método cuantitativo de PCR se puede utilizar para la titulación de lotes del virus de la enteritis hemorrágica y presenta una alta correlación con la titulación in vivo utilizando pollos (R2 0.98, P = 0.007). Este método puede ser relevante en países en los que no se dispone de pavos libres de patógenos específicos y en los que no se permite la importación de células RP19, la única célula que admite la propagación efectiva del virus de la enteritis hemorrágica.


Assuntos
Doenças das Aves Domésticas/virologia , Siadenovirus/fisiologia , Animais , Embrião de Galinha , Galinhas/virologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA