Valeur Ethnobotanique De Annona Muricata Utilisee Dans Le Traitement De Certaines Pathologies Au Sud-Benin

L’utilisation d’Annona muricata dans le traitement de diverses pathologies humaines prend de plus en plus d’ampleur au Bénin. Le but de la présente étude est de faire l’inventaire des maladies traitées par l’utilisation de cette plante. Pour ce faire, une enquête ethnobotanique a été réalisée auprès de 77 herboristes et 170 tradithérapeutes des Départements de l’Ouémé et du Plateau, du Littoral, de l’Atlantique et du Mono. Les données collectées étaient relatives à la structure écologique de l’arbre Annona muricata, aux différents organes utilisés et les maladies traitées, au mode d’emploi, etc. Ces données ont été analysées avec le logiciel SPSS (Statistical Package for Social Sciences) pour la détermination des statistiques descriptives en termes de pourcentage et de moyenne. Il ressort de l’étude que les acteurs enquêtés étaient majoritairement des hommes (74,9%),non scolarisés (40,1%), d’origine Goun (27,1%), Cotafon (19,8%) et Nago (18,2%). Les caractéristiques écologiques de A. muricata ont varié significativement (p<0,05) selon les enquêtés. Le mode de multiplication de l’arbre, selon les enquêtés,se fait principalement par la graine (82,6%). Les principaux organes d’Annonamuricata utilisés pour le traitement des maladies sont majoritairement le fruit (86,2%), la feuille (66,4%) et l’écorce (62,8%). Les principaux modes de préparation des organes étaient la tisane (97,2%), ladécoction (93,5%), et la poudre (76,9%). L’Annonamuricata était majoritairement utilisé, selon les enquêtés, pour le traitement de l’insomnie (70,9%), le cancer (70%), le paludisme (59,9%), l’hypertension artérielle (58,7%), le vertige (57,5)…Ainsi, vu les résultats, ce travail a permis de connaitre la valeur ethnobotanique d’Annona muricata. The use of Annona muricata(A. muricata) in the treatment of various human pathologies is becoming more and more widespread in Benin. The aim of this study was to inventory the diseases treated by the use of this plant. For this purpose, an ethnobotanical survey was carried out among 77 herbalists and 170 traditional therapists from the Departments of Ouémé and Plateau, Littoral, Atlantic and Mono. The data collected was relative, to the ecological structure of the Annona muricata tree, the different organs used and the diseases treated, the use instructions, etc. The data was collected in the form of a questionnaire. These data had been analysed with the Statistical Package for Social Sciences (SPSS) software for the determination of descriptive statistics in terms of percentage and average. The study showed that the majority of the actorssurveyed were men (74.9%), unschooled (40.1%), ethnic groups as Goun (27.1%), Cotafon (19.8%) and Nago (18.2%). The ecological characteristics of A. muricatavaried significantly (p<0.05) according to the surveyed actors. The main method of multiplication of the tree is by seeds (82.6%). The main organs of Annona muricata used for diseases treatment were usually the fruit (86.2%), the leaf (66.4%) and the bark (62.8%). According to the actors, Annona muricata was mainly used for the treatment of insomnia (70.9%), cancer (70%), malaria (59.9%), high blood pressure (58.7%), vertigo (57.5), etc. The main method of organ preparation was herbal tea (97.2%), decoction (93.5%), and powder (76.9%). Therefore, at the results showed, this study allowed to know ethnobotanic value of Annona muricata

Enabling effective maize seed system in low-income countries of West Africa: Insights from Benin

Introduction Access to high-quality seeds remains a key constraint to the intensification of crop production in low-income countries. In this study, we analyzed maize seed production and distribution systems in Benin to identify leverage points for effective seed systems, a prerequisite for improving maize production. Methods Semi-structured interviews were conducted with 81 seed producers selected in seven municipalities across the three phytogeographical zones of Benin. Key informant interviews were also conducted with ten public and private stakeholders involved in maize seed systems in Benin. Results and discussion Findings showed that the legal and institutional frameworks governing seed systems in Benin were recently reinforced with a national seed policy, the creation and operationalization of the National Committee of Plant Seeds and the existence of regulations and rules on the production, quality control, certification, trade, and packaging of seeds. In addition, enabling conditions to facilitate the involvement of the private sector have been greatly improved with the revision of modalities for obtaining approval for the production and distribution of seeds in Benin. While the seed sector is improving and both public and private stakeholders are involved in maize seed production and distribution, synergies among stakeholders need to be strengthened. Strengthening business and marketing skills of seed producers through training and promoting the comparative advantages of improved seeds in increasing yield and production among maize farmers could be a promising avenue. Connecting seed producers with maize farmers' organizations coupled with ICT-based agro-advisories could boost the development of the maize seed sector, and ultimately the maize value chain

Exact distribution of a pattern in a set of random sequences generated by a Markov source: applications to biological data

<p>Abstract</p> <p>Background</p> <p>In bioinformatics it is common to search for a pattern of interest in a potentially large set of rather short sequences (upstream gene regions, proteins, exons, etc.). Although many methodological approaches allow practitioners to compute the distribution of a pattern count in a random sequence generated by a Markov source, no specific developments have taken into account the counting of occurrences in a set of independent sequences. We aim to address this problem by deriving efficient approaches and algorithms to perform these computations both for low and high complexity patterns in the framework of homogeneous or heterogeneous Markov models.</p> <p>Results</p> <p>The latest advances in the field allowed us to use a technique of optimal Markov chain embedding based on deterministic finite automata to introduce three innovative algorithms. Algorithm 1 is the only one able to deal with heterogeneous models. It also permits to avoid any product of convolution of the pattern distribution in individual sequences. When working with homogeneous models, Algorithm 2 yields a dramatic reduction in the complexity by taking advantage of previous computations to obtain moment generating functions efficiently. In the particular case of low or moderate complexity patterns, Algorithm 3 exploits power computation and binary decomposition to further reduce the time complexity to a logarithmic scale. All these algorithms and their relative interest in comparison with existing ones were then tested and discussed on a toy-example and three biological data sets: structural patterns in protein loop structures, PROSITE signatures in a bacterial proteome, and transcription factors in upstream gene regions. On these data sets, we also compared our exact approaches to the tempting approximation that consists in concatenating the sequences in the data set into a single sequence.</p> <p>Conclusions</p> <p>Our algorithms prove to be effective and able to handle real data sets with multiple sequences, as well as biological patterns of interest, even when the latter display a high complexity (PROSITE signatures for example). In addition, these exact algorithms allow us to avoid the edge effect observed under the single sequence approximation, which leads to erroneous results, especially when the marginal distribution of the model displays a slow convergence toward the stationary distribution. We end up with a discussion on our method and on its potential improvements.</p

Impairing flow-mediated endothelial remodeling reduces extravasation of tumor cells

Tumor progression and metastatic dissemination are driven by cell-intrinsic and biomechanical cues that favor the growth of life-threatening secondary tumors. We recently identified pro-metastatic vascular regions with blood flow profiles that are permissive for the arrest of circulating tumor cells. We have further established that such flow profiles also control endothelial remodeling, which favors extravasation of arrested CTCs. Yet, how shear forces control endothelial remodeling is unknown. In the present work, we aimed at dissecting the cellular and molecular mechanisms driving blood flow-dependent endothelial remodeling. Transcriptomic analysis of endothelial cells revealed that blood flow enhanced VEGFR signaling, among others. Using a combination of in vitro microfluidics and intravital imaging in zebrafish embryos, we now demonstrate that the early flow-driven endothelial response can be prevented upon specific inhibition of VEGFR tyrosine kinase and subsequent signaling. Inhibitory targeting of VEGFRs reduced endothelial remodeling and subsequent metastatic extravasation. These results confirm the importance of VEGFR-dependent endothelial remodeling as a driving force of CTC extravasation and metastatic dissemination. Furthermore, the present work suggests that therapies targeting endothelial remodeling might be a relevant clinical strategy in order to impede metastatic progression.</p

Circulating Human Eosinophils Share a Similar Transcriptional Profile in Asthma and Other Hypereosinophilic Disorders

Eosinophils are leukocytes that are released into the peripheral blood in a phenotypically mature state and are capable of being recruited into tissues in response to appropriate stimuli. Eosinophils, traditionally considered cytotoxic effector cells, are leukocytes recruited into the airways of asthma patients where they are believed to contribute to the development of many features of the disease. This perception, however, has been challenged by recent findings suggesting that eosinophils have also immunomodulatory functions and may be involved in tissue homeostasis and wound healing. Here we describe a transcriptome-based approach-in a limited number of patients and controls-to investigate the activation state of circulating human eosinophils isolated by flow cytometry. We provide an overview of the global expression pattern in eosinophils in various relevant conditions, e.g., eosinophilic asthma, hypereosinophilic dermatological diseases, parasitosis and pulmonary aspergillosis. Compared to healthy subjects, circulating eosinophils isolated from asthma patients differed in their gene expression profile which is marked by downregulation of transcripts involved in antigen presentation, pathogen recognition and mucosal innate immunity, whereas up-regulated genes were involved in response to non-specific stimulation, wounding and maintenance of homeostasis. Eosinophils from other hypereosinophilic disorders displayed a very similar transcriptional profile. Taken together, these observations seem to indicate that eosinophils exhibit non-specific immunomodulatory functions important for tissue repair and homeostasis and suggest new roles for these cells in asthma immunobiology

Genome-wide detection of a TFIID localization element from an initial human disease mutation

Eukaryotic core promoters are often characterized by the presence of consensus motifs such as the TATA box or initiator elements, which attract and direct the transcriptional machinery to the transcription start site. However, many human promoters have none of the known core promoter motifs, suggesting that undiscovered promoter motifs exist in the genome. We previously identified a mutation in the human Ankyrin-1 (ANK-1) promoter that causes the disease ankyrin-deficient Hereditary Spherocytosis (HS). Although the ANK-1 promoter is CpG rich, no discernable basal promoter elements had been identified. We showed that the HS mutation disrupted the binding of the transcription factor TFIID, the major component of the pre-initiation complex. We hypothesized that the mutation identified a candidate promoter element with a more widespread role in gene regulation. We examined 17 181 human promoters for the experimentally validated binding site, called the TFIID localization sequence (DLS) and found three times as many promoters containing DLS than TATA motifs. Mutational analyses of DLS sequences confirmed their functional significance, as did the addition of a DLS site to a minimal Sp1 promoter. Our results demonstrate that novel promoter elements can be identified on a genome-wide scale through observations of regulatory disruptions that cause human disease

On the political economics of taxation

Previous analysis have found mixed results on the effects of flat taxes, in terms of efficiency, equity and tax complexity. After reviewing some of the main theoretical arguments that suggest that the political process plays a crucial role in shaping tax systems, we apply them to the case of flat taxes in Estonia

On the political economics of tax reforms: survey and empirical assessment

Political constraints and incentives are the true driver of tax reforms. This paper reviews the political economics literature on personal income tax systems and reforms to see how political mechanisms help explain tax reforms. We take some of the implications of these theories to the data using LABREF, a database that identifies labor tax reforms in the European Union for the period 2000–2007, and control for economic and labor market factors.We find that political variables carry more weight than economic variables, and we show empirical regularities that support political economy theories. We also find that governments tended to reform more in better economic times, engaging in pro-cyclical behavior