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ABSTRACT: INTRODUCTION: Hemophilia A is an X linked recessive hemorrhagic disorder caused by mutations in the F8 gene that lead to qualitative and/or quantitative deficiencies of coagulation factor VIII (FVIII). Molecular diagnosis of hemophilia A is challenging because of the high number of different causative mutations that are distributed throughout the large F8 gene. Molecular studies of these mutations are essential in order to reinforce our understanding of their pathogenic effect responsible for the disorder. Aim In this study we have performed molecular analysis of 28 Tunisian hemophilia A patients and analyzed the F8 mutation spectrum. METHODS: We screened the presence of intron 22 and intron 1 inversion in severe hemophilia A patients by southern blotting and polymerase chain reaction (PCR). Detection of point mutations was performed by dHPLC/sequencing of the coding F8 gene region. We predict the potential functional consequences of novel missense mutations with bioinformatics approaches and mapping of their spatial positions on the available FVIII 3D structure. RESULTS: We identified 23 different mutations in 28 Tunisian hemophilia A patients belonging to 22 unrelated families. The identified mutations included 5 intron 22 inversions, 7 insertions, 4 deletions and 7 substitutions. In total 18 point mutations were identified, of which 9 are located in exon 14, the most mutated exonic sequence in the F8 gene. Among the 23 mutations, 8 are novel and not deposited in the HAMSTeRS database nor described in recently published articles. CONCLUSION: The mutation spectrum of Tunisian hemophilia A patients is heterogeneous with the presence of some characteristic features. Virtual slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1693269827490715.  相似文献   
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IntroductionFew studies have investigated the relationship between dietary pattern and household food insecurity. The objective of the present analysis was to describe the food consumption patterns and to relate these with the prevalence of food insecurity in the context of a rural community.MethodologyThree hundred and seven (307) randomly selected households in Kilosa district participated in the study. Data were collected during the rainy season (February–May) and post harvest season (September–October) in the year 2011. Food consumption pattern was determined using a 24-h dietary recall method. Food insecurity data were based on the 30 day recall experience to food insecurity in the household. Factor analysis method using Principal Components extraction function was used to derive the dietary patterns and correlation analysis was used to establish the existing relationship between household food insecurity and dietary patterns factor score.ResultsFour food consumption patterns namely (I) Meat and milk; (II) Pulses, legumes, nuts and cooking oils; (III) fish (and other sea foods), roots and tubers; (IV) Cereals, vegetables and fruits consumption patterns were identified during harvest season. Dietary patterns identified during the rainy season were as follows: (I) Fruits, cooking oils, fats, roots and tubers (II) Eggs, meat, milk and milk products (III) Fish, other sea foods, vegetables, roots and tubers and (IV) Pulses, legumes, nuts, cereals and vegetables. Household food insecurity was 80% and 69% during rainy and harvest–seasons, respectively (P = 0.01). Household food insecurity access scale score was negatively correlated with the factor scores on household dietary diversity.ConclusionFood consumption patterns and food insecurity varied by seasons with worst scenarios most prevalent during the rainy season. The risk for inadequate dietary diversity was higher among food insecure households compared to food secure households. Effort geared at alleviating household food insecurity could contribute to consumption of a wide range of food items at the household level.  相似文献   
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The interactive effects of light intensity, NaCl, nitrogen, and phosphorus on intracellular biomass content and extracellular polymeric substance production were assessed for Arthrospira sp. (Spirulina) in a two-phase culture process using principal component analysis and central composite face design. Under high light intensity (120 μmol photons m?2?s?1) and low NaCl (1 gL?1), NaNO3, and K2HPO4 (0.5 g L?1), the carbohydrate content was maximized to 26.61%. Interaction of both K2HPO4 (1.6 gL?1) and NaCl (1.19 gL?1) with low NaNO3 (0.5 gL?1) achieved the maximum content of lipids (15.62%), while high NaCl (40 gL?1), K2HPO4, and NaNO3 (4.5 gL?1) enhanced mainly total carotenoids (0.85%). Conversely, under low light intensity of 10 μmol photons m?2?s?1 combined with 11.76 gL?1 of NaCl, 0.5 gL?1 of NaNO3, and 2.68 gL?1 of K2HPO4, the phycobiliprotein content reached its highest level (16.09%). The maximum extracellular polymeric substance (EPS) production (0.902 gg?1?DW) was triggered under moderate light of 57.25 μmol photons m?2?s?1 and interaction of high NaCl (40 gL?1) and K2HPO4 (4.5 gL?1) with low NaNO3 (0.5 gL?1). The maximization ratios of intracellular biomass content in terms of carbohydrate, lipid, total carotenoid, phycobiliprotein, and EPS production were 3.55-, 1.73-, 9.55-, 2.92-, and 1.46-fold, respectively, greater than those obtained at optimal growth conditions. This study demonstrated that the multiple stress factors applied to the adopted two-phase culture process could be a promising strategy to produce biomass enriched in various high-value compound.  相似文献   
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Ganoderma species are a group of fungi that have the ability to degrade lignin polymers and cause severe diseases such as stem and root rot and can infect economically important plants and perennial crops such as oil palm, especially in tropical countries such as Malaysia. Unfortunately, very little is known about the complex interplay between oil palm and Ganoderma in the pathogenesis of the diseases. Proteomic technologies are simple yet powerful tools in comparing protein profile and have been widely used to study plant–fungus interaction. A critical step to perform a good proteome research is to establish a method that gives the best quality and a wide coverage of total proteins. Despite the availability of various protein extraction protocols from pathogenic fungi in the literature, no single extraction method was found suitable for all types of pathogenic fungi. To develop an optimized protein extraction protocol for 2-DE gel analysis of Ganoderma spp., three previously reported protein extraction protocols were compared: trichloroacetic acid, sucrose and phenol/ammonium acetate in methanol. The third method was found to give the most reproducible gels and highest protein concentration. Using the later method, a total of 10 protein spots (5 from each species) were successfully identified. Hence, the results from this study propose phenol/ammonium acetate in methanol as the most effective protein extraction method for 2-DE proteomic studies of Ganoderma spp.  相似文献   
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The genus Myrtus L. (Myrtaceae family) comprises two species, Myrtus communis L. (known as common myrtle) growing wild all around the Mediterranean basin and Myrtus nivellei Batt . and Trab . (known as Saharan myrtle), found in central Sahara. Only one country, Algeria, hosts both species, M. communis in the North and M. nivellei in the South. The aim of this review was to collect, summarize, and compare the main results reported relative to the essential oils isolated from aerial parts of both species: botanical aspects, habitat, traditional use, chemical composition, new compounds, antimicrobial activity, antioxidant activity, anti‐inflammatory effect, and insecticidal activity. Both essential oils have potential applications in human health.  相似文献   
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The shape and morphology of endothelial cells (ECs) lining the blood vessels are a good indicator for atheroprone and atheroprotected sites. ECs of blood vessels experience both wall shear stress (WSS) and cyclic stretch (CS). These mechanical stimuli influence the shape and morphology of ECs. A few models have been proposed for predicting the morphology of ECs under WSS or CS. In the present study, a mathematical cell population model is developed to simulate the morphology of ECs under combined WSS and CS conditions. The model considers the cytoskeletal filaments, cell–cell interactions, and cell–extracellular matrix interactions. In addition, the reorientation and polymerization of microfilaments are implemented in the model. The simulations are performed for different conditions: without mechanical stimuli, under pure WSS, under pure CS, and under combined WSS and CS. The results are represented as shape and morphology of ECs, shape index, and angle of orientation. The model is validated qualitatively and quantitatively with several experimental studies, and good agreement with experimental studies is achieved. To the best of our knowledge, it is the first model for predicting the morphology of ECs under combined WSS and CS condition. The model can be used to indicate the atheroprone regions of a patient’s artery.  相似文献   
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