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1.
Heliyon ; 7(6): e07312, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34222688

RESUMO

The use of organic fertiliser to improve soil health is crucial to halting the downward trend of crop yields in sub-Saharan Africa. If this goal is to be achieved, however, farmers require support to adopt organic fertiliser practices that match their attitudes and decision-making capacity. This study evaluated farmers' attitudes to a set of prevailing organic fertiliser practices and their associated behavioural costs (difficulty). The explanatory Rasch model was applied to a set of primary data from 250 farming households in north-east Ghana. The results showed that the average attitude of farmers was much less than the difficulty estimate of an average organic fertiliser practice, although the practices generally showed a moderate difficulty. On average, farmers' attitudes matched just three of sixteen practices on the scale, with most (70 %) of the farmers showing very weak attitudes towards the input. Latent regression results revealed that the weak attitude levels were strongly related to key factors in the farmers' background, including education, resource endowment and access to extension services. Participation in determining policies on organic fertiliser use enhances farmers' knowledge and skills concerning use of the input. Hence, access to such policies can replace education for the less-educated majority of farmers. Thus, training programmes are proposed that develop the average farmer's capacity to adopt these practices in this area, especially the less difficult ones. Supporting farmers with the acquisition of animal-drawn vehicles can also facilitate uptake of the more difficult organic fertiliser practices and increase use of the input.

2.
J Environ Manage ; 246: 897-908, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31276894

RESUMO

Natura 2000 areas are designated according to the EU's Birds and Habitats Directives in order to protect particular habitats and species. A variety of these habitats and species are particularly sensitive to deposition of nitrogen caused by ammonia emissions. Livestock farming is the primary source of this pollution. The purpose of this paper is to compare the costs of reaching the ammonia emission targets for different livestock farms near Natura 2000 sites in the Netherlands, Germany (Schleswig-Holstein), and Denmark. These countries have some of the highest NH3 deposition rates in Europe, and Germany in particular will have to implement new measures to reach the NEC requirements for 2030. This will also benefit nature sites in Denmark as a large share of the ammonia emissions is dispersed over long distances. The general regulation includes implementation of BAT technologies and emission ceilings. The analysis looks at regulatory aspects, the emission requirements and the cost of implementing the technologies to reduce emissions further. The selected case farms are a finisher farm and a dairy farm, and the distance to a Natura 2000 site is 400 and 2000 m. In all three countries, relatively few livestock farms are situated near or inside Natura 2000 areas. The regulatory approach is very different in the three countries and key issues are: additional deposition from projects, neighbouring livestock farms (cumulation), the inclusion of background deposition and the use of the critical loads concept. The Dutch PAS system is interesting as projected reductions in emissions are distributed as additional "room for development" today. The costs for the case farm with finishers in Schleswig-Holstein are the highest as the Filter Decree requires the use of air scrubbers. The findings suggest that farms 400 m from a Natura 2000 site in the Netherlands face lower and less costly constraints than in the other countries, whereas the opposite is the case for farms 2000 m from Natura 2000 sites. The requirements near Natura 2000, where strict requirements apply, are so high that farms will expand at a different site instead.


Assuntos
Amônia , Gado , Animais , Dinamarca , Europa (Continente) , Fazendas , Alemanha , Países Baixos
3.
Immunity ; 42(2): 321-331, 2015 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-25680273

RESUMO

T helper 1 (Th1) cell-associated immunity exacerbates ileitis induced by oral Toxoplasma gondii infection. We show here that attenuated ileitis observed in interleukin-22 (IL-22)-deficient mice was associated with reduced production of Th1-cell-promoting IL-18. IL-22 not only augmented the expression of Il18 mRNA and inactive precursor protein (proIL-18) in intestinal epithelial cells after T. gondii or Citrobacter rodentium infection, but also maintained the homeostatic amount of proIL-18 in the ileum. IL-22, however, did not induce the processing to active IL-18, suggesting a two-step regulation of IL-18 in these cells. Although IL-18 exerted pathogenic functions during ileitis triggered by T. gondii, it was required for host defense against C. rodentium. Conversely, IL-18 was required for the expression of IL-22 in innate lymphoid cells (ILCs) upon T. gondii infection. Our results define IL-18 as an IL-22 target gene in epithelial cells and describe a complex mutual regulation of both cytokines during intestinal infection.


Assuntos
Infecções por Enterobacteriaceae/imunologia , Interleucina-18/imunologia , Interleucinas/imunologia , Mucosa Intestinal/imunologia , Toxoplasmose/imunologia , Animais , Células Cultivadas , Citrobacter rodentium/imunologia , Infecções por Enterobacteriaceae/microbiologia , Células Epiteliais/imunologia , Ileíte/imunologia , Ileíte/microbiologia , Ileíte/parasitologia , Íleo/imunologia , Íleo/microbiologia , Íleo/parasitologia , Inflamação/imunologia , Interferon gama/biossíntese , Interleucina-18/biossíntese , Interleucinas/genética , Mucosa Intestinal/microbiologia , Mucosa Intestinal/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infiltração de Neutrófilos/imunologia , Neutrófilos/imunologia , Técnicas de Cultura de Órgãos , RNA Mensageiro/biossíntese , Células Th1/imunologia , Toxoplasma/imunologia , Toxoplasmose/parasitologia , Regulação para Cima , Interleucina 22
4.
Environ Sci Pollut Res Int ; 19(2): 390-402, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21792583

RESUMO

BACKGROUND, AIM AND SCOPE: Studies on the contribution of milk production to global greenhouse gas (GHG) emissions are rare (FAO 2010) and often based on crude data which do not appropriately reflect the heterogeneity of farming systems. This article estimates GHG emissions from milk production in different dairy regions of the world based on a harmonised farm data and assesses the contribution of milk production to global GHG emissions. MATERIALS, METHODS AND RESULTS: The methodology comprises three elements: (1) the International Farm Comparison Network (IFCN) concept of typical farms and the related globally standardised dairy model farms representing 45 dairy regions in 38 countries; (2) a partial life cycle assessment model for estimating GHG emissions of the typical dairy farms; and (3) standard regression analysis to estimate GHG emissions from milk production in countries for which no typical farms are available in the IFCN database. Across the 117 typical farms in the 38 countries analysed, the average emission rate is 1.50 kg CO(2) equivalents (CO(2)-eq.)/kg milk. The contribution of milk production to the global anthropogenic emissions is estimated at 1.3 Gt CO(2)-eq./year, accounting for 2.65% of total global anthropogenic emissions (49 Gt; IPCC, Synthesis Report for Policy Maker, Valencia, Spain, 2007). DISCUSSION AND CONCLUSION: We emphasise that our estimates of the contribution of milk production to global GHG emissions are subject to uncertainty. Part of the uncertainty stems from the choice of the appropriate methods for estimating emissions at the level of the individual animal.


Assuntos
Indústria de Laticínios/métodos , Monitoramento Ambiental/métodos , Efeito Estufa , Dióxido de Carbono/análise , Dióxido de Carbono/metabolismo , Manipulação de Alimentos , Metano/análise , Metano/metabolismo , Modelos Biológicos , Óxido Nitroso/análise , Óxido Nitroso/metabolismo , Análise de Regressão , Incerteza
5.
J Exp Med ; 206(13): 3047-59, 2009 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-19995958

RESUMO

Peroral infection with Toxoplasma gondii leads to the development of small intestinal inflammation dependent on Th1 cytokines. The role of Th17 cells in ileitis is unknown. We report interleukin (IL)-23-mediated gelatinase A (matrixmetalloproteinase [MMP]-2) up-regulation in the ileum of infected mice. MMP-2 deficiency as well as therapeutic or prophylactic selective gelatinase blockage protected mice from the development of T. gondii-induced immunopathology. Moreover, IL-23-dependent up-regulation of IL-22 was essential for the development of ileitis, whereas IL-17 was down-regulated and dispensable. CD4(+) T cells were the main source of IL-22 in the small intestinal lamina propria. Thus, IL-23 regulates small intestinal inflammation via IL-22 but independent of IL-17. Gelatinases may be useful targets for treatment of intestinal inflammation.


Assuntos
Interleucina-17/fisiologia , Interleucina-23/fisiologia , Interleucinas/fisiologia , Intestino Delgado/patologia , Metaloproteinase 2 da Matriz/fisiologia , Toxoplasma/patogenicidade , Animais , Feminino , Intestino Delgado/imunologia , Metaloproteinase 9 da Matriz/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Piperazinas/farmacologia , Pirimidinas/farmacologia , Toxoplasmose Animal/imunologia , Interleucina 22
6.
Trop Anim Health Prod ; 40(4): 269-79, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18557190

RESUMO

The Ugandan dairy sector is developing rapidly over recent years and is dominated by small-scale farmers owning more than 90 percent of the national cattle population. Due to market forces and higher competition for production factors, milk production systems are intensifying, necessitating proper understanding of the new production tendencies. Three intensive and four extensive production systems were identified and analysed, using TIPI-CAL (Technology Impact Policy Impact Calculations model). The results show that the production systems are very different in many respects but share similar development trends. Whereas intensive systems use graded animals and invest heavily into feeding, buildings and machinery, extensive systems use local breeds and invest minimally. Total cost of milk production falls with increasing herd size, while dairy returns vary among farms from 18 to 35 USD/100 Kg of milk. All systems make an economic profit, except the intensive one-cow farm, which heavily employs family resources in dairying. Due to better management of resources and access to inputs and markets, dairy farming closer to urban areas and using improved breeds is highly profitable, especially with larger herd sizes. Stakeholders should favour such practices as well as others which can improve productivity, especially in African countries where traditional systems dominate dairying.


Assuntos
Bovinos , Indústria de Laticínios/economia , Leite/economia , Animais , Feminino , Modelos Econômicos , Uganda
7.
Hum Gene Ther ; 14(5): 483-94, 2003 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-12691613

RESUMO

Therapeutic vaccination with dendritic cells (DC) can lead to tumor regression in animal models and has shown promising results in the first clinical trials of metastatic renal cell carcinoma and malignant melanoma. In vitro data and results of a clinical phase I/II trial using DC tumor fusions in patients with progressive metastatic renal cell carcinoma are presented here. In addition to toxicity and feasibility, complex immune monitoring was a point of interest. DC precursor cells were obtained from the peripheral blood mononuclear cells (PBMCs) of healthy donors and were fused with either allogeneic (8 patients) or autologous (4 patients) renal tumor cells. In total, 12 patients with progressive metastatic renal cell carcinoma were treated with an average of 2.8 x 10(7) tumor cells fused with 1.8 x 10(7) DC each administered on days 0, 28, and 56 intradermally. Fusion efficacy for the tumor cells used was 14.3% +/- 7.8%. Cell viability was 59.8% +/- 6.8% after fusion and irradiation. We observed no adverse effects and no difference in clinical outcome between the allogeneic and the autologous treatment. Eight patients remained in a progressive disease state and four patients in a stable disease state. T-cell immunity was carefully monitored before, during, and after treatment. Delayed-type hypersensitivity (DTH) reaction using tumor cells was positive after treatment in 7 of 12 patients, 2 of whom were found to have stable disease. An increase in the reactivity against recall antigens was seen in most patients. Interestingly, cytotoxicity of peripheral blood lymphocytes (PBLs) against renal cell carcinoma cells increased during treatment as well as the percentage of interferon-gamma-secreting cells. This effect was significantly enhanced within the group that had stable disease. The lack of adverse effects together with positive immunologic signs justifies further investigation of this novel therapeutic approach. Further studies are necessary to test for clinical effectiveness in patients with tumors, especially those with less advanced disease.


Assuntos
Vacinas Anticâncer/uso terapêutico , Carcinoma de Células Renais/terapia , Células Dendríticas/imunologia , Neoplasias Renais/terapia , Adulto , Idoso , Antígenos CD/metabolismo , Vacinas Anticâncer/imunologia , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/patologia , Fusão Celular , Citocinas/biossíntese , Citocinas/sangue , Testes Imunológicos de Citotoxicidade , Células Dendríticas/citologia , Imunofluorescência , Humanos , Isoantígenos/imunologia , Neoplasias Renais/imunologia , Neoplasias Renais/patologia , Ativação Linfocitária , Masculino , Microscopia de Fluorescência , Pessoa de Meia-Idade , Metástase Neoplásica , Linfócitos T Citotóxicos/imunologia , Resultado do Tratamento , Células Tumorais Cultivadas
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