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Use of ELISPOT and ELISA to evaluate IFN-gamma, IL-10 and IL-4 responses in conventional pigs 总被引：2，自引：0，他引：2
ELISPOT and ELISA were standardised for pig interferon-gamma (IFN-gamma), interleukin-10 (IL-10) and interleukin-4 (IL-4) with the aim to study the evolution of the immune response in conventional pigs from birth to 6 months of age and also to compare results of both techniques. Five pigs were bled at 1, 6, 9, 12 and 22 weeks of age and peripheral blood mononuclear cells (PBMC) were stimulated with phytohemagglutinin. The frequencies of cytokine secreting cells (CSC) and the levels of secreted cytokines were compared. For IFN-gamma the mean of CSC increased with age (p<0.05) from an average of 486/10(6) PBMC at first week of age to 1256/10(6) PBMC at 22 weeks of age. No correlation was found between the number of IFN-gamma CSC and the cytokine levels obtained by ELISA. For IL-10, frequencies of CSC did not increase with age of pigs, having a low of 315/10(6) PBMC at first week of age and a high of 1485/10(6) PBMC at six weeks. Comparison of ELISA and ELISPOT results for IL-10 showed a certain degree of correlation (r=0.74; p<0.05). Spontaneous secretion was observed in unstimulated cultures. For IL-4, frequencies of CSC were low (50-70/10(6) PBMC). In this case, comparison of ELISA and ELISPOT could not be done because cytokine levels in culture supernatants were often below the detection limit of the IL-4 ELISA. All these values can serve as a reference for future studies and also, our observations suggest that ELISPOT and ELISA should be carefully interpreted and do not necessarily correlate. 相似文献
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Segalés J Piñeiro C Lampreave F Nofrarías M Mateu E Calsamiglia M Andrés M Morales J Piñeiro M Domingo M 《Veterinary research》2004,35(3):275-282
The objective of this study was to determine the serum concentration levels of selected acute phase proteins (APP), haptoglobin (HPT) and pig-major acute phase protein (pig-MAP), in postweaning multisystemic wasting syndrome (PMWS) affected pigs and PCV2-subclinically infected pigs. In a first study, a group of 15 eight-week-old conventional pigs from a PMWS affected farm were bled and a complete necropsy, histopathology and in situ hybridisation to detect PCV2 were performed. Based on the results, pigs were classified as suffering from PMWS (n = 10) or healthy animals (n = 5). In a second study, a group of 45 pigs from another PMWS affected farm were selected and bled at 3, 7, 12 and 28 weeks of age. The assessment of PCV2 infection status in these pigs was retrospectively done by PCV2 PCR in serum samples. Selected APP were measured in the serum of all studied pigs by means of radial immunodiffusion. Mean HPT and pig-MAP levels were significantly increased (p = 0.004 and p = 0.0006 respectively) in PMWS-affected pigs when compared to levels found in healthy pigs (2.52 +/- 0.88 mg/mL vs. 1.06 +/- 0.73 mg/mL for HPT and 3.81 +/- 1.53 mg/mL vs. 0.76 +/- 0.34 mg/mL for pig-MAP). In the second study, no significant difference in mean HPT and pig-MAP values were observed between PCV2 PCR positive and negative pigs of any age. However, both APP increased significantly with age in PCV2 PCR negative pigs. Altogether, the present results suggest that APP levels are significantly increased in pigs that develop PMWS, but not in animals with a PCV2 subclinical infection. 相似文献
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Impacts of biodiversity loss on ocean ecosystem services 总被引：1，自引：0，他引：1
Worm B Barbier EB Beaumont N Duffy JE Folke C Halpern BS Jackson JB Lotze HK Micheli F Palumbi SR Sala E Selkoe KA Stachowicz JJ Watson R 《Science (New York, N.Y.)》2006,314(5800):787-790
Human-dominated marine ecosystems are experiencing accelerating loss of populations and species, with largely unknown consequences. We analyzed local experiments, long-term regional time series, and global fisheries data to test how biodiversity loss affects marine ecosystem services across temporal and spatial scales. Overall, rates of resource collapse increased and recovery potential, stability, and water quality decreased exponentially with declining diversity. Restoration of biodiversity, in contrast, increased productivity fourfold and decreased variability by 21%, on average. We conclude that marine biodiversity loss is increasingly impairing the ocean's capacity to provide food, maintain water quality, and recover from perturbations. Yet available data suggest that at this point, these trends are still reversible. 相似文献
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Porcine reproductive and respiratory syndrome (PRRS) virus (PRRSV) infections are characterized by prolonged viremia and viral shedding consistent with incomplete immunity. Type I interferons (IFN) are essential for mounting efficient antiviral innate and adaptive immune responses, but in a recent study, North American PRRSV genotype 2 isolates did not induce, or even strongly inhibited, IFN-α in plasmacytoid dendritic cells (pDC), representing “professional IFN-α-producing cells”. Since inhibition of IFN-α expression might initiate PRRSV pathogenesis, we further characterized PRRSV effects and host modifying factors on IFN-α responses of pDC. Surprisingly, a variety of type 1 and type 2 PRRSV directly stimulated IFN-α secretion by pDC. The effect did not require live virus and was mediated through the TLR7 pathway. Furthermore, both IFN-γ and IL-4 significantly enhanced the pDC production of IFN-α in response to PRRSV exposure. PRRSV inhibition of IFN-α responses from enriched pDC stimulated by CpG oligodeoxynucleotides was weak or absent. VR-2332, the prototype genotype 2 PRRSV, only suppressed the responses by 34%, and the highest level of suppression (51%) was induced by a Chinese highly pathogenic PRRSV isolate. Taken together, these findings demonstrate that pDC respond to PRRSV and suggest that suppressive activities on pDC, if any, are moderate and strain-dependent. Thus, pDC may be a source of systemic IFN-α responses reported in PRRSV-infected animals, further contributing to the puzzling immunopathogenesis of PRRS. 相似文献
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Joan Marull Carme Font Enric Tello Nofre Fullana Elena Domene Manel Pons Elena Galán 《Landscape Ecology》2016,31(2):317-336
Context
The role of agricultural landscapes in biodiversity conservation is an emerging topic in a world experiencing a worrying decrease of species richness. Farm systems may either decrease or increase biological diversity, depending on land-use intensities and management.Objectives
We present an intermediate disturbance-complexity model (IDC) of cultural landscapes aimed at assessing how different levels of anthropogenic disturbance on ecosystems affect the capacity to host biodiversity depending on the land matrix heterogeneity. It is applied to the Mallorca Island, amidst the Mediterranean biodiversity hotspot.Methods
The model uses the disturbance exerted when farmers alter the Net Primary Production through land-use change as well as when they remove a share of it (HANPP), together with Shannon–Wiener index (H′) of land-cover diversity. The model is tested with a twofold-scalar experimental design (1:50,000 and 1:5000) of a set of landscape units along three time points (1956, 1989, 2011). Species richness of breeding and wintering birds, taken as a biodiversity proxy, is used in an exploratory factor analysis.Results
The results clearly show that when intermediate levels of HANPP are performed within intermediate levels of complexity (H′) in landscape patterns, like agro-forest mosaics, great bird species richness and high socio-ecological resilience can be maintained. Yet, these complex-heterogeneous landscapes are currently vanishing due to industrial farm intensification, rural abandonment and urban sprawl.Conclusions
The results make apparent the usefulness of transferring the concept of intermediate disturbance-complexity interplay to cultural landscapes. Our spatial-explicit IDC model can be used as a tool for strategic environmental assessment of land-use planning.10.
Mayara de Moura Pereira Mariana Machado Evangelista Enric Gisbert Elizabeth Romagosa 《Aquaculture Research》2019,50(8):2181-2190
The aim of this study was to assess the activity of gastric, pancreatic and intestinal digestive enzymes during the embryonic and larval development of Nile tilapia (Oreochromis niloticus) GIFT strain Aqua America® 1 obtained from a broodstock fed two levels of crude protein (CP). A total of 72 females and 24 males, 10 hapas, two CP levels (32% and 38%) and six phases of embryonic (cleavage, blastula, gastrula) and larval (hatching, 7 and 10 days post hatch, dph) stages were used. The eggs were collected in cleavage, blastula and gastrula stages, 300 mg was collected, and kept in cryogenic tubes in liquid nitrogen. For the samples at larval stage, the remaining eggs were separated according to crude protein level and kept in hatcheries and samples were collected on 7 and 10 dph the same way as before. A total of 48 samples were collected: at each protein level (32% and 38% CP), four samples were collected in each phase of embryonic and larval development. Statistical differences were not observed during embryonic development for acid proteases, trypsin, amylase and lipase activity at both levels of crude protein (32 and 38% CP). Differences for acid proteases were noticed on 7 dph; trypsin and amylase on 7 dph and 10 dph. Significant differences on blastula and 7 dph for protease; as for aminopeptidase, there was significant difference on 7 dph. The data indicated early appearance of digestive enzymes in Nile tilapia broodfish receiving 32% CP taking into account the rapid growth and development of this species. 相似文献