387 research outputs found
Social determinants of health in Tunisia: the case-analysis of Ariana
<p>Abstract</p> <p>Background</p> <p>Few research projects have analyzed how social determinants of health impact cities in North Africa. The sustained growth in these countries has nevertheless proven to exacerbate health disparities and create many social and economic inequalities. This strategic analysis examines selected social determinants of health in a major urban centre of Tunisia, identifies the most influential stakeholders able to influence equity/inequity, and reviews the accomplishments and need for action to foster health equity.</p> <p>Methods</p> <p>This analysis was performed through a literature review and participatory research methods that included focus groups discussions and interview with key informants.</p> <p>Results</p> <p>Access to health care, changes in lifestyles, housing issues and gender-related inequities are prime, socially-determined elements that affect health in Ariana.</p> <p>Conclusion</p> <p>Recognition of emerging health issues is needed along with improved inter and intrasectoral coordination among stakeholders. The community-participatory approach used in this paper proved to be a useful scoping technique for this setting. A similar methodology could be used by other researchers as a first step toward health equity action at a city level.</p
Comparison of Computational Models for Assessing Conservation of Gene Expression across Species
Assessing conservation/divergence of gene expression across species is important for the understanding of gene regulation evolution. Although advances in microarray technology have provided massive high-dimensional gene expression data, the analysis of such data is still challenging. To date, assessing cross-species conservation of gene expression using microarray data has been mainly based on comparison of expression patterns across corresponding tissues, or comparison of co-expression of a gene with a reference set of genes. Because direct and reliable high-throughput experimental data on conservation of gene expression are often unavailable, the assessment of these two computational models is very challenging and has not been reported yet. In this study, we compared one corresponding tissue based method and three co-expression based methods for assessing conservation of gene expression, in terms of their pair-wise agreements, using a frequently used human-mouse tissue expression dataset. We find that 1) the co-expression based methods are only moderately correlated with the corresponding tissue based methods, 2) the reliability of co-expression based methods is affected by the size of the reference ortholog set, and 3) the corresponding tissue based methods may lose some information for assessing conservation of gene expression. We suggest that the use of either of these two computational models to study the evolution of a gene's expression may be subject to great uncertainty, and the investigation of changes in both gene expression patterns over corresponding tissues and co-expression of the gene with other genes is necessary
La rhodophycée Gelidium spinosum (S.G. Gmelin) P.C. Silva, des côtes de Monastir (Tunisie) : quelques éléments hydrobiologiques et potentialités en agar-agar
La rhodophycée Gelidium spinosum (S.G. Gmelin) P.C. Silva (Rhodophycées ; Gélidiales) a été étudiée pendant une année, depuis septembre 2000 jusqu’à août 2001, sur la côte de Monastir (Est de la Tunisie). Les résultats globaux obtenus montrent que le poids humide maximum (environ 37 g/individu) a été atteint en mai. La longueur maximale (environ 11 cm) a été enregistrée en juin. La biomasse maximale en poids humide (environ 7000 g/m2) a été obtenue en mai. Quant à la fertilité, elle a varié entre 0%(Mai) et 100% (Septembre, Juin, Juillet et Août). Concernant le rendement en agar, le maximum a été obtenu en avril (33.4 % du poids sec), La force de gel maximale a atteint environ 705 g.cm-² (juin). Le point de gélification et le point de fusion les plus élevés ont été obtenus respectivement en août (34.33°C) et septembre (94.33°C).Mots-clés : Gelidium spinosum, poids, longueur, biomasse, fertilité, agar-agar
Recherche des facteurs les plus influents sur le rendement et la qualité de l’agar- agar de la rhodophycée Gelidium spinosum (S.G. Gmelin) P.C. Silva
Cinq (5) facteurs physico-chimiques : concentration en carbonate de sodium, température et durée de carbonatation, temps de digestion et pression, ont été étudiés simultanément pour voir leur effet sur l’extrait d’agar de Gelidium spinosum. L’étude a mis en évidence l’influence plus ou moins importante dechacun de ces facteurs sur les réponses recherchées (rendement d’extraction, force de gel, point de gélification et point de fusion). Différentes interactions plus ou moins importantes ont pu être également mises en évidence entre les facteurs étudiés.Mots-clés : gelidium spinosum, facteurs influents, interactions, agar-agar, rendement, qualité
Comparison of Two Output-Coding Strategies for Multi-Class Tumor Classification Using Gene Expression Data and Latent Variable Model as Binary Classifier
Multi-class cancer classification based on microarray data is described. A generalized output-coding scheme based on One Versus One (OVO) combined with Latent Variable Model (LVM) is used. Results from the proposed One Versus One (OVO) outputcoding strategy is compared with the results obtained from the generalized One Versus All (OVA) method and their efficiencies of using them for multi-class tumor classification have been studied. This comparative study was done using two microarray gene expression data: Global Cancer Map (GCM) dataset and brain cancer (BC) dataset. Primary feature selection was based on fold change and penalized t-statistics. Evaluation was conducted with varying feature numbers. The OVO coding strategy worked quite well with the BC data, while both OVO and OVA results seemed to be similar for the GCM data. The selection of output coding methods for combining binary classifiers for multi-class tumor classification depends on the number of tumor types considered, the discrepancies between the tumor samples used for training as well as the heterogeneity of expression within the cancer subtypes used as training data
Analyzing Recent Coronary Heart Disease Mortality Trends in Tunisia between 1997 and 2009.
BACKGROUND: In Tunisia, Cardiovascular Diseases are the leading causes of death (30%), 70% of those are coronary heart disease (CHD) deaths and population studies have demonstrated that major risk factor levels are increasing.
OBJECTIVE: To explain recent CHD trends in Tunisia between 1997 and 2009.
METHODS: DATA SOURCES: Published and unpublished data were identified by extensive searches, complemented with specifically designed surveys.
ANALYSIS: Data were integrated and analyzed using the previously validated IMPACT CHD policy model. Data items included: (i)number of CHD patients in specific groups (including acute coronary syndromes, congestive heart failure and chronic angina)(ii) uptake of specific medical and surgical treatments, and(iii) population trends in major cardiovascular risk factors (smoking, total cholesterol, systolic blood pressure (SBP), body mass index (BMI), diabetes and physical inactivity).
RESULTS: CHD mortality rates increased by 11.8% for men and 23.8% for women, resulting in 680 additional CHD deaths in 2009 compared with the 1997 baseline, after adjusting for population change. Almost all (98%) of this rise was explained by risk factor increases, though men and women differed. A large rise in total cholesterol level in men (0.73 mmol/L) generated 440 additional deaths. In women, a fall (-0.43 mmol/L), apparently avoided about 95 deaths. For SBP a rise in men (4 mmHg) generated 270 additional deaths. In women, a 2 mmHg fall avoided 65 deaths. BMI and diabetes increased substantially resulting respectively in 105 and 75 additional deaths. Increased treatment uptake prevented about 450 deaths in 2009. The most important contributions came from secondary prevention following Acute Myocardial Infarction (AMI) (95 fewer deaths), initial AMI treatments (90), antihypertensive medications (80) and unstable angina (75).
CONCLUSIONS: Recent trends in CHD mortality mainly reflected increases in major modifiable risk factors, notably SBP and cholesterol, BMI and diabetes. Current prevention strategies are mainly focused on treatments but should become more comprehensive
Use of evidence to support healthy public policy: a policy effectiveness-feasibility loop
Public policy plays a key role in improving population health and in the control of diseases, including non-communicable diseases.
However, an evidence-based approach to formulating healthy public policy has been difficult to implement, partly on account of barriers
that hinder integrated work between researchers and policy-makers. This paper describes a “policy effectiveness–feasibility loop” (PEFL) that
brings together epidemiological modelling, local situation analysis and option appraisal to foster collaboration between researchers and
policy-makers. Epidemiological modelling explores the determinants of trends in disease and the potential health benefits of modifying
them. Situation analysis investigates the current conceptualization of policy, the level of policy awareness and commitment among key
stakeholders, and what actually happens in practice, thereby helping to identify policy gaps. Option appraisal integrates epidemiological
modelling and situation analysis to investigate the feasibility, costs and likely health benefits of various policy options. The authors illustrate
how PEFL was used in a project to inform public policy for the prevention of cardiovascular diseases and diabetes in four parts of the eastern
Mediterranean. They conclude that PEFL may offer a useful framework for researchers and policy-makers to successfully work together to
generate evidence-based policy, and they encourage further evaluation of this approach
Effect of Diet Supplementation on the Expression of Bovine Genes Associated with Fatty Acid Synthesis and Metabolism
Conjugated linoleic acids (CLA) are of important nutritional and health benefit to human. Food products of animal origin are their major dietary source and their concentration increases with high concentrate diets fed to animals. To examine the effects of diet supplementation on the expression of genes related to lipid metabolism, 28 Angus steers were fed either pasture only, pasture with soybean hulls and corn oil, pasture with corn grain, or high concentrate diet. At slaughter, samples of subcutaneous adipose tissue were collected, from which RNA was extracted. Relative abundance of gene expression was measured using Affymetrix GeneChip Bovine Genome array. An ANOVA model nested within gene was used to analyze the background adjusted, normalized average difference of probe-level intensities. To control experiment wise error, a false discovery rate of 0.01 was imposed on all contrasts. Expression of several genes involved in the synthesis of enzymes related to fatty acid metabolism and lipogenesis such as stearoyl-CoA desaturase (SCD), fatty acid synthetase (FASN), lipoprotein lipase (LPL), fatty-acyl elongase (LCE) along with several trancription factors and co-activators involved in lipogenesis were found to be differentially expressed. Confirmatory RT-qPCR was done to validate the microarray results, which showed satisfactory correspondence between the two platforms. Results show that changes in diet by increasing dietary energy intake by supplementing high concentrate diet have effects on the transcription of genes encoding enzymes involved in fat metabolism which in turn has effects on fatty acid content in the carcass tissue as well as carcass quality. Corn supplementation either as oil or grain appeared to significantly alter the expression of genes directly associated with fatty acid synthesis
Modelling transmission and control of Mycobacterium avium subspecies paratuberculosis within Irish dairy herds with compact spring calving
Paratuberculosis is a chronic bacterial infection of the intestine in cattle caused by Mycobacterium avium subspecies paratuberculosis (Map). To better understand Map transmission in Irish dairy herds, we adapted the French stochastic individual-based epidemiological simulation model to account for seasonal herd demographics. We investigated the probability of Map persistence over time, the within-herd prevalence over time, and the relative importance of transmission pathways, and assessed the relative effectiveness of test-and-cull control strategies. We investigated the impact on model outputs of calf separation from cows (calves grazed on pasture adjacent to cows vs. were completely separated from cows) and test-and-cull. Test-and-cull scenarios consisted of highly test-positive cows culled within 13 or 4 weeks after detection, and calf born to highly test-positive cows kept vs removed. We simulated a typical Irish dairy herd with on average 82 lactating cows, 112 animals in total. Each scenario was iterated 1000 times to adjust variation caused by stochasticity. Map was introduced in the fully naive herd through the purchase of a moderately infectious primiparous cow. Infection was considered to persist when at least one infected animal remained in the herd or when Map was present in the environment.
The probability of Map persistence 15 years after introduction ranged between 32.2-42.7 % when calves and cows had contact on pasture, and between 18.9-29.4 % when calves and cows were separated on pasture. The most effective control strategy was to cull highly test-positive cows within four weeks of detection (absolute 10 % lower persistence compared to scenarios without control). Removing the offspring of highly test-positive dams did not affect either Map persistence or within-herd prevalence of Map.
Mean prevalence 15 years after Map introduction was highest (63.5 %) when calves and cows had contact on pasture. Mean prevalence was 15 % lower (absolute decrease) when cows were culled within 13 weeks of a high test-positive result, and 28 % lower when culled within 4 weeks.
Around calving, the infection rate was high, with calves being infected in utero or via the general indoor environment (most important transmission routes). For the remainder of the year, the incidence rate was relatively low with most calves being infected on pasture when in contact with cows. Testing and culling was an effective control strategy when it was used prior to the calving period to minimize the number of highly infectious cows present when calves were born
La mucormycose nasosinusienne: Diagnostic et modalites therapeutiques
La mucormycose est une infection fongique rare qui touche essentiellement les sujets immunodéprimés et notamment diabétiques. La localisation de cette maladie est surtout nasosinusienne. Son pronostic reste mauvais malgré le développement des moyens de prise en charge. Nous rapportons deux cas de mucormycose nasosinusienne à travers lesquels nous discutons les aspects cliniques et radiologiques, ainsi que les moyens thérapeutiques de cette maladie. Il s’agit d’un homme et d’une femme âgés respectivement de 56 et 52 ans. Le premier était diabétique et la deuxième insuffisante rénale. L’évolution était lente dans le premier cas et très rapide dans le deuxième. Le diagnostic était dans les deux cas histologique. L’évolution était, dans le premier cas, favorable après traitement associant débridement chirurgical et amphotéricine B, et dans le second rapidement fatale. Conclusion : La mucormycose nasosinusienne est une affection grave dont le pronostic peut être mauvais malgré le traitement.Mots clés : Infection fongique, mucormycose rhinocérébrale, zygomycètes
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