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1.
Agric Syst ; 175: 1-12, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31582872

RESUMO

We evaluated the usefulness of a co-design process to generate a relevant basket of options for climbing bean cultivation in the context of a large-scale project. The aim was to identify a range of options sufficiently diverse to be of interest for farmers of widely-different resource endowment. The co-design process consisted of three cycles of demonstration, evaluation and re-design in the eastern and southwestern highlands of Uganda in 2014-2015. Evaluations aimed to distinguish preferences of farmers between the two areas, and among farmers of different gender and socio-economic backgrounds. Farmers, researchers, extension officers and NGO staff re-designed treatments for demonstrations in the next season. Climbing bean yields and evaluation scores varied between seasons and sites. Evaluation scores were not always in line with yields, revealing that farmers used multiple evaluation criteria next to yield, such as marketability of varieties, availability of inputs and ease of staking methods. The co-design process enriched the basket of options, improved the relevance of options demonstrated and enhanced the understanding of preferences of a diversity of users. Developing options for resource-poor farmers was difficult, however, because they face multiple constraints. The basket of options developed in this study can be applied across the East-African highlands, with an 'option-by-context' matrix as a starting point for out-scaling. The study also showed, however, that consistent recommendations about the suitability of technologies for different types of farmers were hard to identify. This highlights the importance of a basket of options with flexible combinations of practices rather than developing narrowly specified technology packages for static farm types.

2.
Agric Ecosyst Environ ; 261: 186-200, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29970947

RESUMO

Climbing beans offer potential for sustainable intensification of agriculture, but their cultivation constitutes a relatively complex technology consisting of multiple components or practices. We studied uptake of improved climbing bean production practices (improved variety, input use and management practices) through co-designed demonstrations and farmer-managed adaptation trials with 374 smallholder farmers in eastern and southwestern Uganda. A sub-set of these farmers was monitored one to three seasons after introduction. About 70% of the farmers re-planted climbing beans one season after the adaptation trial, with significant differences between eastern (50%) and southwestern Uganda (80-90%). Only 1% of the farmers used all of the improved practices and 99% adapted the technology. On average, farmers used half of the practices in different combinations, and all farmers used at least one of the practices. Yield variability of the trials was large and on average, trial plots did not yield more than farmers' own climbing bean plots. Yet, achieved yields did not influence whether farmers continued to cultivate climbing bean in the subsequent season. Uptake of climbing beans varied with household characteristics: poorer farmers cultivated climbing beans more often but used fewer of the best-bet practices; male farmers generally used more practices than female farmers. Planting by poorer farmers resulted in adaptations such as growing climbing beans without fertilizer and with fewer and shorter stakes. Other relationships were often inconsistent and farmers changed practices from season to season. The diversity of farmer responses complicates the development of recommendation domains and warrants the development of a basket of options from which farmers can choose. Our study shows how adoption of technologies consisting of multiple components is a complicated process that is hard to capture through the measurement of an adoption rate at a single point in time.

3.
Animal ; 11(5): 881-889, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28031076

RESUMO

Evaluation of lifetime productivity of individual animals in response to various interventions allows assessment of long-term investment opportunities for farmers. In order to gain a better understanding of promising feed interventions for improvement of small ruminant production in Southwestern Nigeria, a dynamic modelling approach was used to explore the effect of different feeding strategies on the lifetime productivity of West African Dwarf (WAD) goats. Modifications were made to the current version of Livestock Simulator developed for cattle production to simulate goat production systems particularly for WAD goats. Effects of changes in input parameters (quality of feed and potential adult weight) confirmed the sensitivity of the modelled weight development and reproductive performance. The values of simulated model outputs corresponded well with observed values for most of the variables, except for the pre-weaning mortality rate in the cut-and-carry system where a wide discrepancy between simulated (2.1%) and observed (23%) data was found. The scenario analysis showed that simulated goats in the free grazing system attained sexual maturity and kidded much later than those in the grazing with supplementation and the cut-and-carry systems. The simulated results suggested that goats require supplementation with protein and energy sources, in order to promote lifetime productivity, early sexual maturity and higher birth weight. In terms of economic returns based on feed cost alone, the moderately intense system produced the most profit. We therefore conclude that grazing with adequate supplementation using farm-generated feed resources offers an opportunity for improving smallholder goat production systems in West Africa.


Assuntos
Criação de Animais Domésticos/métodos , Cabras/fisiologia , Animais , Modelos Teóricos , Nigéria
4.
DNA Cell Biol ; 15(6): 429-42, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8672239

RESUMO

A 5.4-kb cDNA encoding the protein that binds to the B Box of the plasminogen activator inhibitor-1 (PAI-1) gene was isolated and sequenced. The protein, named helicase-like transcription factor (HLTF), contains a DNA-binding domain, a RING finger domain, and seven helicase domains and is homologous to SWI/SNF proteins. Two HLTF mRNAs of 5.5 and 4.5 kb were detected in most human tissues, a single gene was located on chromosome 3q24-25, and the protein was located in the nucleoplasm. Two HLTF proteins differing in translation start site (Met-1 or Met-123) were obtained by in vitro translation in reticulocyte lysate or by immunoprecipitation from HeLa cell nuclear extracts. In vitro transcription from the PAI-1 promoter in HeLa cell extracts was inhibited by HLTF antibodies and by the HLTF DNA binding domain. Over-expression of HLTF or HLTFMet123 produced a three-fold induction of PAI-1-LUC transient expression in HeLa cells. Mutation of the PAI-1 B Box led to an eight-fold reduction of basal PAI-1-LUC expression in these cell lines, but did not affect the four- to six-fold induction by phorbol esters.


Assuntos
Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica/fisiologia , Inibidor 1 de Ativador de Plasminogênio/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Sequência de Bases , Núcleo Celular/química , Cromossomos Humanos Par 3 , Clonagem Molecular , DNA/metabolismo , DNA Helicases/genética , DNA Complementar/genética , Proteínas de Ligação a DNA/análise , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Células HeLa , Humanos , Dados de Sequência Molecular , Peso Molecular , Músculo Esquelético , Especificidade de Órgãos , Ligação Proteica , RNA Mensageiro/análise , Sequências Reguladoras de Ácido Nucleico/genética , Análise de Sequência de DNA , Fatores de Transcrição/análise , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Transcrição Gênica/genética , Dedos de Zinco/genética
5.
Verh K Acad Geneeskd Belg ; 55(3): 225-64, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8342330

RESUMO

Plasminogen activators and their inhibitors play a pivotal role in maintaining the hemostatic balance in blood and also in other proteolytic processes such as cell migration and tumor invasion. The main physiological inhibitor of the plasminogen activators is plasminogen activator inhibitor-1 (PAI-1). The effect of PMA on the endogenous PAI-1 production and on the expression of transfected promoter/reporter gene constructs was studied in HUVEC and in the HT1080 and HeLa cell lines. Addition of PMA (> or = 10 nM) to monolayer cell cultures induced a 2- to 5.5-fold increase of PAI-1 antigen production within 8-24 h. In HUVEC, PMA (160 nM) induced both the 2.4 kb and 3.4 kb mRNA species of PAI-1: 3.1 +/- 1.1 and 1.7 +/- 0.8-fold (n = 6), respectively, within 8 h. Run-on experiments confirmed that this increase is at least partially mediated by increased gene transcription. When HUVEC, HT1080 and HeLa, transfected with an 826 bp or a 336 bp PAI-1 gene promoter fragment, were stimulated with 160 nM phorbol 12-myristate 13-acetate (PMA), the CAT activity was induced 4-, 3.5- and 10-fold respectively for both constructs, revealing that PMA responsive sequences are present in the proximal 336 bp of the PAI-1 promoter. Substitution mutations in the regions encompassing nucleotides -78 to -69 (TGGGTGGGGC) or -61 to -54 (TGAGTTCA), but not in the regions -155 to -149 (TGCCTCA) or -84 to -76 (AGTGAGTGG) reduced this induction. Gel electrophoresis of double stranded -65 to -50 oligonucleotides of the PAI-1 promoter region and nuclear extracts from HeLa cells produced a gel shift pattern, similar to that obtained with a AP-1 consensus oligomer, and excess unlabeled AP-1 oligomer reverted binding suggesting that this region of the PAI-1 promoter is an AP-1-like binding site. Gel electrophoresis of double stranded -82 to -65 oligonucleotide with HeLa nuclear extracts revealed a gel shift pattern of three bands. Sp1 consensus oligomer competed with the binding of two of these bands and AP-2 consensus sequence oligomer with the binding to the third band. The -82 to -65 oligomer also bound to purified AP-2 and Sp1 proteins. Southwestern blotting of HeLa nuclear extracts revealed that the labeled oligomer covering region -82 to -65 bound the proteins with molecular weights of 52 kD and 72 kD.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Regulação da Expressão Gênica , Inativadores de Plasminogênio/genética , Sequência de Aminoácidos , Sequência de Bases , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Biblioteca Gênica , Humanos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Ligação Proteica , Acetato de Tetradecanoilforbol/farmacologia , Fatores de Transcrição
6.
J Biol Chem ; 267(21): 15086-91, 1992 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-1634545

RESUMO

Phorbol 12-myristate 13-acetate induces a 3- and 10-fold induction of chloramphenicol acetyltransferase (CAT) activity in HT1080 and HeLa cells, respectively, following transient transfection of a 336-base pair plasminogen activator inhibitor-1 (PAI-1) promoter fragment linked to a CAT reporter gene. Substitution mutations in the regions encompassing nucleotides -78 to -69 (TGGGTGGGGC) or -61 to -54 (TGAGTTCA), but not in the regions -155 to -149 (TGCCTCA) or -84 to -76 (AGTGAGTGG) reduced this induction. Gel electrophoresis of double-stranded -65 to -50 oligonucleotides of the PAI-1 promoter region and nuclear extracts from Hela cells produced a gel shift pattern similar to that obtained with a AP-1 consensus oligomer, and excess unlabeled AP-1 oligomer reverted binding, suggesting that this region of the PAI-1 promoter is an AP-1-like binding site. Gel electrophoresis of double-stranded -82 to -65 oligonucleotides with HeLa nuclear extracts revealed a gel shift pattern of three bands; Sp1 consensus oligomer competed with the binding to two of these bands and AP-2 consensus sequence oligomer with the binding to the third band. The -82 to -65 oligomer also bound to purified AP-2 and Sp1 proteins. Southwestern blotting of HeLa nuclear extracts revealed that the labeled oligomer spanning region -82 to -65 bound to proteins with molecular masses of 52 and 72 kDa. Consensus AP-2 oligonucleotides competed for binding of the labeled -82 to -65 oligonucleotide to the 52-kDa protein, but consensus Sp-1 oligonucleotides did not compete for binding to the 72-kDa compound. The 72-kDa component binding to the -82 to -65 region may represent a new protein involved in transcriptional regulation.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Inativadores de Plasminogênio/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Fator de Transcrição Sp1/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Fatores de Transcrição/metabolismo , Sequência de Bases , Cloranfenicol O-Acetiltransferase/biossíntese , Cloranfenicol O-Acetiltransferase/genética , Eletroforese , Indução Enzimática , Células HeLa , Humanos , Immunoblotting , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Plasmídeos , Regiões Promotoras Genéticas , Fator de Transcrição AP-2 , Transfecção , Células Tumorais Cultivadas
7.
Br J Nutr ; 82(2): 91-6, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10743480

RESUMO

Total substitution of soyabean protein for animal protein in the diet has been repeatedly shown to lower plasma cholesterol levels in hypercholesterolaemic individuals. A new, highly palatable, high-protein soya drink may allow replacement of a significant percentage of animal protein in the diet. The soya drink was given, within a crossover design v. a cows' milk preparation of similar composition and taste, to twenty-one severely hypercholesterolaemic patients (mean baseline plasma cholesterol 8.74 mmol/l) with a history of resistance to or intolerance of statin treatment. Each dietary supplement was given for 4 weeks, with a 4-week interval between treatments, Plasma lipid levels were monitored every 2 weeks during each dietary sequence. The concomitant dietary treatment, which had been followed for a long time by all patients, was carefully monitored throughout the study. The soya supplementation reduced plasma total cholesterol level by 6.5%, when given first, and by 7.4% when given after cows' milk. When given first, cows' milk resulted in a small, non-significant reduction of plasma cholesterol level (-3.9%), and when given after soya, it changed total plasma cholesterol to a minimal extent (-1.6%). Changes in total and LDL-cholesterol levels after 2 and 4 weeks of soya v. cows' milk treatment were, thus, respectively -6.1, -7.0 and -6.2, -7.8% (both P < 0.05). These first data from a double-blind study confirm a significant cholesterol-lowering effect of soyabean protein, even when only partly replacing animal protein in the diet, in individuals with extreme plasma cholesterol elevations.


Assuntos
Colesterol/sangue , Hipercolesterolemia/dietoterapia , Leite , Proteínas de Soja/uso terapêutico , Adulto , Idoso , Análise de Variância , Animais , LDL-Colesterol/sangue , Contraindicações , Estudos Cross-Over , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases , Hipercolesterolemia/sangue , Masculino , Pessoa de Meia-Idade
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