558 research outputs found

    Analyser l’impact d’un projet de micro-finance : l’exemple d’ADéFI à Madagascar.

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    Cette étude s’attache à analyser l’impact d’une institution de microfinance opérant auprès de micro- entrepreneurs à Antananarivo (Madagascar). Elle débute par un passage en revue de la littérature récente consacrée à l’impact socio-économique de la micro-finance. Elle décrit ensuite succinctement l’état de l’offre et de la demande de micro-crédit à Madagascar. Elle présente enfin les résultats de l’analyse de l’impact des financements accordés par ADéFI. La méthodologie retenue consiste à comparer la situation d’un échantillon de micro-entreprises clientes d’ADéFI représentatives de l’ensemble de la clientèle de l’institution à celle d’un groupe de contrôle construit de façon quasi- expérimentale par une technique standard d’appariement. Dans l’ensemble, les résultats des analyses concluent à un impact positif du projet. En statique, les évaluations conduites en 2001 et 2004 montrent que les micro-entreprises financées enregistrent de meilleures performances en moyenne que les UPI non financées. En dynamique, les analyses menées sont plus nuancées. Si l’impact positif du projet est clairement établi en phase de croissance, son effet en période de récession paraît plus incertain.This study aims at assessing the impact of a microfinance institution serving micro-entrepreneurs in Antananarivo (Madagascar). It starts by reviewing the recent literature on the socioeconomic impact of microfinance, then moves on to describe the current state of supply and demand of micro-credit in Madagascar. Finally, the results of the examination of the impact of ADéFI financing on micro- entreprises are presented. The methodology consists of comparing the situation of a representative sample of micro-enterprise ADéFI clients with a control group, constructed in an almost experimental way through a standard matching technique. Overall, the results indicate a positive impact of the project. Taken as a snapshot, the studies conducted in 2001 and 2004 indicate that the micro- enterprises financed recorded better average performance than informal production units without funding. With a dynamic perspective however, the results were more nuanced. If the positive effect of the project is clear during growth phases, its effect during contractions appears less certain.impact assessment; Madagascar; score de propension; évaluation d'impact; Microfinance; propensity score matching;

    OR 47: Renal endothelin receptor type B upregulation in rats with low or high renin hypertension

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    Endothelin-1 (ET-1) is a potent renal and systemic vasoactive peptide. It acts through ETA and ETB receptors. We investigated density and subtype distribution of ET-1 receptors in hearts and kidneys of normotensive and hypertensive rats. Five groups of uninephrectomized Wistar rats were put on a low salt diet for six weeks. During this period, three groups of rats drank tap water and two groups received saline. One group of each regimen received DOCA subcutaneousely (1.6 mg/day). The fifth group of rats had the left renal artery clipped to induce 1K1C hypertension. At 6 weeks, mean arterial pressure (MAP) was recorded in conscious rats via a femoral artery catheter. Binding assays using 125I-ET-1 were carried out on membrane preparations in the presence and absence of the ETA receptor antagonist FR139317. On tap water, MAP was at 121.8±3.3 mmHg and DOCA or saline did not raise this MAP. On DOCA-salt and in 1K1C rats, MAP was increased to 154.5±5.8 mmHg (p<0.001) and 218.4±10.5 (p<0.001) mmHg, respectively. ET receptor subtypes were not equally expressed in the heart and the kidney: ETA was predominantly expressed in the heart, whereas ETB was predominant in the kidney. Both hypertensive models, the DOCA-salt and the 1K1C rats showed further significant changes: i) Cardiac weight index compared to controls of 2.49±0.06 mg/g was higher (p<0.001) at 3.89±0.10 and 4.86±0.18 mg/g in DOCA-salt and 1K1C hypertension, respectively, and kidney weight index compared to controls of 4.78±0.22 mg/g was higher at 10.10±0.54 mg/g in DOCA-salt (p<0.001) but tended to be below controls in 1K1C rats. ii) In the kidneys, the density of the ETB receptor subtype was upregulated in DOCA-salt and 1K1C rats from 160±8 to 217±12 and 190±2 fmol/mg (p<0.05), respectively, and ETA tended to be downregulated. iii) Plasma renin activity was decrased in DOCA-salt rats from 17±3 to 0.17±0.01 ng/ml/h and increased in 1K1C rats on low salt diet to 30±5 ng/ml/h (p<0.001). We conclude that upregulation of the ETB receptor mediating vasodilation and downregulation of the ETA receptor mediating vasoconstriction is compatible with a mainly renal counterregulatory effect of endothelin-1 to hypertension. This counterregulation may occur in both low and high renin models of hypertension. Am J Hypertens (2004) 17, 20A-21A; doi: 10.1016/j.amjhyper.2004.03.04

    Statins (HMG-CoA reductase inhibitors) reduce CD40 expression in human vascular cells

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    Objective: HMG-CoA reductase inhibitors (statins) possess anti-inflammatory and immunomodulatory properties that are independent of their lipid-lowering action. As the CD40-CD40L signaling pathway is implicated in the modulation of inflammatory responses between vascular cells, involving adhesion molecules, pro-inflammatory cytokines, chemokines, we sought to investigate the potential role of statins in regulating the expression of CD40. Methods and Results: Using Western blot, flow cytometry and immunohistochemistry analyses, we observed that four different statins reduced IFN-γ-induced CD40 expression in human vascular cells (endothelial cells, smooth muscle cells, macrophages and fibroblasts). This effect was dose-dependent (from 5 μM to 80 nM) and reversed by addition of l-mevalonate. Activation of vascular cells by human recombinant CD40L, as measured by ELISA for IL-6, IL-8 and MCP-1, was strongly reduced when cells were treated with statins. Immunostaining of human carotid atherosclerotic lesions of patients subjected to statin treatment revealed less CD40 expression on a ‘per vascular cell' basis compared to control patients. Although many pleiotropic effects of statins are mediated by nitric oxide synthase (NOS)- or peroxisome proliferator-activated receptor (PPAR)-dependent signaling pathways, we observed similar statin-induced reduction of CD40 expression using NOS inhibitors or different PPAR ligands. Conclusion: Statins decrease CD40 expression and CD40-related activation of vascular cells. These effects are partially reversed by the HMG-CoA reductase product l-mevalonate and are mediated by NOS- or PPAR-dependent pathways. Altogether, these findings provide mechanistic insight into the beneficial effects of statins on atherogenesis. They also provide a scientific rationale for the use of statins as immunomodulators after organ transplantatio

    Rapid Site-Directed Mutagenesis Using Two-PCR-Generated DNA Fragments Reproducing the Plasmid Template

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    We describe a new rapid and efficient polymerase chain reaction (PCR)-based site-directed mutagenesis method. This procedure is effective with any plasmid and it employs four oligonucleotide primers. One primer contains the desired mutation, the second is oriented in the opposite direction (one of these two primers should be phosphorylated), and the third and fourth should be coding in complementary fashion for a unique restriction site to be introduced in a nonessential region. The method consists of two simultaneous PCR reactions; the PCR products are digested with the enzyme that recognizes the newly introduced unique restriction site and then ligased and used to transform competent bacteria. Additionally, the use of Dpn I facilitates the elimination of template DNA. The newly introduced restriction site is essential for ligation in the correct orientation of the two-PCR products and is further used for mutant screening. Resulting plasmids carry both the new restriction site and the desired mutation. Using this method, more than 20 mutants have already been generated (using two different kinds of templates); all these mutants were sequenced for the desired mutation and transfected into AtT-20 cells and the expressed mutant proteins encoded by the vector were assayed

    Ontogenetic loops in habitat use highlight the importance of littoral habitats for early life-stages of oceanic fishes in temperate waters

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    General concepts of larval fish ecology in temperate oceans predominantly associate dispersal and survival to exogenous mechanisms such as passive drift along ocean currents. However, for tropical reef fish larvae and species in inland freshwater systems behavioural aspects of habitat selection are evidently important components of dispersal. This study is focused on larval Atlantic herring (Clupea harengus) distribution in a Baltic Sea retention area, free of lunar tides and directed current regimes, considered as a natural mesocosm. A Lorenz curve originally applied in socio-economics to describe demographic income distribution was adapted to a 20 year time-series of weekly larval herring distribution, revealing size-dependent spatial homogeneity. Additional quantitative sampling of distinct larval development stages across pelagic and littoral areas uncovered a loop in habitat use during larval ontogeny, revealing a key role of shallow littoral waters. With increasing rates of coastal change, our findings emphasize the importance of the littoral zone when considering reproduction of pelagic, ocean-going fish species; highlighting a need for more sensitive management of regional coastal zones

    Influence of Different Evolutive Forces on GDF5 Gene Variability

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    The GDF5 gene is involved in the development of skeletal elements, synovial joint formation, tendons, ligaments, and cartilage. Several polymorphisms are present within the gene, and two of them, rs143384 and 143383, were reported to be correlated with osteoarticular disease or muscle flexibility. The aim of this research is to verify if the worldwide distribution of the rs143384 polymorphism among human populations was shaped by selective pressure, or if it was the result of random genetic drift events. Ninety-four individuals of both the male and female sexes, 18–28 years old, from Sardinia were analyzed. We observed the following genotype frequencies: 28.72% of AA homozygotes, 13.83% of GG homozygotes, and 57.45% of AG heterozygotes. The allele frequencies were 0.574 for allele A and 0.426 for allele G. The relationships between the populations were verified via Multidimensional Scaling (MDS). Our data show (i) a clear heterogeneity within the African populations; (ii) a strong differentiation between the African populations and the other populations; and that (iii) the Sardinian population is placed within the European cluster. To reveal possible traces of selective pressure, the Population Branch Statistic (PBS) was calculated; both the rs143384 and 143383 SNPs have low PBS values, suggesting that there are no signals of selective pressure in those areas of the gene

    Interaction of Adenovirus E1A with the HHV8 Promoter of Latent Genes: E1A Proteins are Able to Activate the HHV-8 LANAp in MV3 Reporter Cells

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    Human herpesvirus 8 (HHV-8) is associated with Kaposi’s sarcoma, body cavity-based lymphoma, and Castleman’s disease. Adenoviral (Ad) E1A proteins regulate the activity of cellular and viral promoters/enhancers and transcription factors and can suppress tumorigenicity of human cancers. As (i) HHV-8 and Ad may co-exist in immunocompromised patients and (ii) E1A might be considered as therapeutic transgene for HHV-8-associated neoplasms we investigated whether the promoter of the latency-associated nuclear antigen (LANAp) controlling expression of vCyclin, vFLIP, and LANA proteins required for latent type infection is regulated by E1A. Transfection experiments in MV3 melanoma cells revealed activation of the LANAp by Ad5 E1A constructs containing an intact N terminus (aa 1-119). In particular, an Ad12 E1A mutant, Spm2, lacking six consecutive alanine residues in the “spacer” region activated the HHV-8 promoter about 15-fold compared to vector controls. In summary, we report the activation of the LANAp by E1A as a novel interaction of E1A with a viral promoter. These data may have relevance for the management of viral infections in immunocompromised patients. A role for E1A as a therapeutic in this context remains to be defined

    EXPLORING STUDENTS’ ATTITUDES TOWARDS ONLINE-BASED LEARNING SYSTEM IN THE NEW NORMAL: AN EXPLORATORY FACTOR ANALYSIS

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    The implementation of online learning modality in the “New Normal Education” shifted the track of education institutions across the globe from conducting face-to-face classes to holding online-classes. The study presented in this paper aimed to explore students’ attitude towards online-based learning system in the “New Normal” education. Specifically, it investigated the factor structure and the level of attitudes of 200 students towards online-based learning system. This study utilized a mixed method of research utilizing in-depth interview and a dimension reduction technique through Principal Component Analysis. Results revealed that, attitudes toward online-based learning system is multidimensional exploring eight dimensions namely: Engagement, Convenience, Satisfaction, Technology Acceptance, Adaptability, Interaction, Self-Regulation and Control. Moreover, the level of attitudes of students revealed a high level of convenience, technology acceptance, adaptability, interaction, assessment satisfaction, self-regulation and control and a moderate level of student engagement. Thus, the researchers recommend a training proposal for teachers as well as recalibrating the result of the study utilizing Confirmatory Factor Analysis.   Article visualizations
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