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2.
Poult Sci ; 90(5): 1009-13, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21489947

RESUMEN

Vaccines, antibiotics, and other therapeutic agents used to combat disease in poultry generate recurring costs and the potential of residues in poultry products. Enhancing the immune response using alternative approaches such as selection for increased disease resistance or dietary immunomodulation may be effective additions to the portfolio of strategies the industry applies in poultry health management. The objective of this study was to characterize the effects of dietary supplementation with 3 immunomodulators [ascorbic acid, 1,3-1,6 ß-glucans from baker's yeast, and corticosterone] on cytokine gene expression in the spleen of 3 distinct genetic lines of chickens. Relative mRNA expression levels were determined using quantitative reverse transcriptase PCR for IL-1ß, IL-2, inducible nitric oxide synthase, and toll-like receptors 4 and 15, all of which play important roles in chicken immune function. Expression data were analyzed by mixed model analysis. The only significant effect detected was sex effect (P < 0.04) on expression of IL-1ß. The present findings suggest the need for further investigations into the effects of dietary immunomodulators on cytokine gene expression in chickens so as to generate a better understanding of the immunomodulation process.


Asunto(s)
Pollos/inmunología , Regulación de la Expresión Génica/efectos de los fármacos , Genes MHC Clase II/fisiología , Factores Inmunológicos/farmacología , Bazo/metabolismo , Alimentación Animal , Animales , Ácido Ascórbico/farmacología , Corticosterona/farmacología , Citocinas/genética , Citocinas/metabolismo , Dieta/veterinaria , Femenino , Genes MHC Clase II/genética , Masculino , beta-Glucanos/farmacología
3.
J Fish Biol ; 78(4): 1054-72, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21463307

RESUMEN

Fathead minnows Pimephales promelas were exposed to lipopolysaccharide (LPS) and polyinosinic-polycytidylic acid [poly(I:C)] to observe immunological responses during simulated bacterial and viral challenge at the level of gene expression and granulocyte function. Complementary DNA libraries were created from LPS- and poly(I:C)-treated fish and c. 5000 expressed sequence tags (ESTs) were sequenced. The ESTs were subjected to BLASTx analysis and 1500 genes were annotated, grouped by function and 20 immune genes were selected for expression studies by real-time PCR. Lipopolysaccharide treatment significantly downregulated expression of interferon regulatory factor 2 binding protein 1 (nine-fold), Chemokine (C-X-C motif) ligand 12a (three-fold) and TNF-related apoptosis-inducing ligand, TRAIL (two-fold). In poly(I:C)-treated fish, a significant upregulation was observed for IFN-inducible and antiviral proteins belonging to the family of Mx proteins (73-fold) and chemokine CCL-C5a (28-fold). Blood neutrophil count was significantly increased in poly(I:C)-treated fish at 24 and 48 h post-injection. Neutrophil extracellular trap release and respiratory burst of kidney granulocytes were suppressed in poly(I:C)-treated fish, while degranulation of primary granules was not affected significantly by the treatment. The changes in gene expression and neutrophil function in P. promelas exposed to LPS and poly(I:C) support the use of this species as an alternative model for studies of pathogen effects on the innate immune system of fishes.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Cyprinidae , Proteínas de Peces , Regulación de la Expresión Génica/efectos de los fármacos , Lipopolisacáridos/farmacología , Neutrófilos/efectos de los fármacos , Poli I-C/farmacología , Animales , Cyprinidae/genética , Cyprinidae/inmunología , Etiquetas de Secuencia Expresada , Proteínas de Peces/genética , Proteínas de Peces/inmunología , Perfilación de la Expresión Génica
4.
Poult Sci ; 89(8): 1635-41, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20634518

RESUMEN

Nutritional modulation of the immune system is an often exploited but poorly characterized process. In chickens and other food production animals, dietary enhancement of the immune response is an attractive alternative to antimicrobial use. A yeast cell wall component, beta-1,3/1,6-glucan, augments the response to disease in poultry and other species; however, the mechanism of action is not clear. Ascorbic acid and corticosterone are better characterized immunomodulators. In chickens, the spleen acts both as reservoir and activation site for leukocytes and, therefore, splenic gene expression reflects systemic immune function. To determine effects of genetic line and dietary immunomodulators, chickens of outbred broiler and inbred Leghorn and Fayoumi lines were fed either a basal diet or an experimental diet containing beta-glucans, ascorbic acid, or corticosterone from 56 to 77 d of age. Spleens were harvested, mRNA was isolated, and expression of interleukin (IL)-4, IL-6, IL-18, macrophage inflammatory protein-1beta, interferon-gamma, and phosphoinositide 3-kinase p110gamma transcripts was measured by quantitative reverse transcription PCR. Effects of diet, genetic line, sex, and diet x genetic line interaction on weight gain and gene expression were analyzed. At 1, 2, and 3 wk after starting the diet treatments, birds fed the corticosterone diet had gained less weight compared with birds fed the other diets (P < 0.001). Sex affected expression of IL-18 (P = 0.010), with higher levels in males. There was a significant interaction between genetic line and diet on expression of IL-4, IL-6, and IL-18 (P = 0.021, 0.006, and 0.026, respectively). Broiler line gene expression did not change in response to the experimental diet. Splenic expression of IL-6 was higher in Leghorns fed the basal or ascorbic acid diets, rather than the beta-glucan or corticosterone diets, whereas the opposite relationship was observed in the Fayoumi line. Expression of IL-4 and IL-18 responded to diet only within the Fayoumi line. The differential splenic expression of birds from diverse genetic lines in response to nutritional immunomodulation emphasizes the need for further study of this process.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Pollos/genética , Citocinas/genética , Inmunomodulación/genética , Bazo/inmunología , Alimentación Animal , Animales , Ácido Ascórbico/farmacología , Pollos/inmunología , Corticosterona/farmacología , Citocinas/inmunología , Cartilla de ADN , Amplificación de Genes , Regulación de la Expresión Génica , Inmunomodulación/fisiología , Interleucina-18/genética , Interleucina-4/genética , Interleucina-6/genética , Fosfatidilinositol 3-Quinasas/genética , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Especificidad de la Especie , Bazo/efectos de los fármacos , beta-Glucanos/farmacología
5.
Dev Biol (Basel) ; 129: 91-102, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18306523

RESUMEN

Certificates of Veterinary Inspection (CVI), generally termed "Health Certificates", are pivotal for ensuring that translocated animals are not diseased or do not harbour significant pathogens. While used very successfully with terrestrial animal movement for decades, CVIs for aquatic animals are not well refined, understood or used, despite the availability of several aquatic animal "certification processes", "permits" and "health certificates", including the OIE model health certificates. Correctly designed CVIs provide the single most economical and effective assurance of disease status (generally freedom from specific diseases or pathogens) for individuals or lots of animals, at any point in time. When issued by a qualified independent third-party (typically a licensed and government accredited veterinarian) they provide the official level of assurance necessary for intrastate, interstate and international trade. Tailored modifications of CVIs are also useful for other purposes requiring the evaluation of animal health (e.g. specific pathogen-free (SPF) assurance for premises, risk-mitigating assurance necessary for insurance policies, breeding soundness assurance of broodstock, etc.). Here we discuss necessary information for aquatic animal CVIs: animal, ownership and location; standardized diagnostic results and their interpretation; and language contained in CVIs. Also addressed is the viability for use with multiple aquatic species and diseases/pathogens of interest, and their use in conjunction with established veterinary inspection procedures. A revised model aquatic CVI, with broad potential use for individual operations, states or countries, is offered for discussion, comment and refinement. In addition an optimally designed model CVI may be of use with electronic systems that are evolving in, for example, Europe, the USA and Australia/New Zealand (e.g. TRACES, e-CVI, e-Certs).


Asunto(s)
Enfermedades de los Animales/prevención & control , Acuicultura/métodos , Certificación/normas , Control de Enfermedades Transmisibles/métodos , Medicina Veterinaria/métodos , Animales , Comercio , Cooperación Internacional , Gestión de Riesgos/métodos
6.
Ann Bot ; 91(6): 697-705, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12714367

RESUMEN

Extensive research shows temperature to be the primary environmental factor controlling the phyllochron, or rate of leaf appearance, of wheat (Triticum aestivum L.). Experimental results suggest that soil temperature at crown depth, rather than air temperature above the canopy, would better predict wheat leaf appearance rates. To test this hypothesis, leaf appearance in spring wheat ('Nordic') was measured in a 2-year field experiment (Nunn clay loam soil; fine, smectitic, mesic Aridic, Argiustoll) with three planting dates and two soil temperature treatments. One temperature treatment (denoted +3C) consisted of heating the soil at crown depth to 3 degrees C above the ambient soil temperature (denoted +0C). Main stem cumulative leaf number was measured at least weekly until flag leaf emergence. Leaf appearance was essentially linear with both air and soil growing degree-days (GDD), although there was a stronger linear relationship with soil GDD in the +0C plants than in +3C plants. A weak positive relationship between planting date and the phyllochron was observed. Unexpectedly, we found that heating the soil did not increase the rate of leaf appearance, as the paradigm would predict. To explain these results, we propose extending the paradigm in two ways. First, three processes are involved in leaf appearance: (1) cell division at the shoot apex forms the primordium; (2) cell division in the intercalary meristem forms the cells that then (3) expand to produce the leaf. Cell division is predominantly controlled by temperature, but cell expansion is considerably more affected by factors other than temperature, explaining the influence of other factors on the phyllochron. Secondly, the vertical distribution of the two meristems and region of cell expansion occur over a significant distance, where temperature varies considerably, and temperature at a specific point (e.g. crown depth) does not account for the entire temperature regime under which leaves are developing.


Asunto(s)
Hojas de la Planta/crecimiento & desarrollo , Temperatura , Triticum/crecimiento & desarrollo , División Celular , Germinación , Lluvia , Estaciones del Año , Semillas/crecimiento & desarrollo , Suelo , Factores de Tiempo
7.
Vojnosanit Pregl ; 55(2 Suppl): 23-8, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9623355

RESUMEN

In this paper we analyzed the clinical manifestation and course of the disease in 47 patients with systemic lupus erythematosus (SLE) and secondary antiphospholipid syndrome (APS) during prospective follow-up that lasted 2-5 years (mean 3.4). The most frequent features of APS were thrombosis (51%) thrombocytopenia (46.8%), and neuropsychiatric disorders (40.4%). These features were predominantly associated with elevated concentrations of IgG aCL isotype or with the presence of both IgG and IgM isotypes. Spectrum of neuropsychiatric disorders included mainly cerebrovascular ischemic disease (63%), but also some other, such as mental disorders and seizures, and, rarely, atypical migraine and transverse myelopathy. Thrombotic events in APS are the most significant for therapeutic and prognostic considerations. The treatment of basic disease (SLE) and conventional management of thromboembolic manifestation with heparin and/or dicoumarol (or warfarin) prevented neither the recurrent thrombosis in 9 patients (37.5%), nor the fatal outcome in 6 patients (12.8%). Further investigations and perhaps more aggressive approach to APS treatment are needed for better clinical care of these patients.


Asunto(s)
Anticuerpos Anticardiolipina/sangre , Síndrome Antifosfolípido/complicaciones , Lupus Eritematoso Sistémico/complicaciones , Adulto , Síndrome Antifosfolípido/diagnóstico , Síndrome Antifosfolípido/inmunología , Femenino , Humanos , Lupus Eritematoso Sistémico/inmunología , Masculino , Estudios Prospectivos
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