20 research outputs found

    Development of ANN optimized mucoadhesive buccal tablet containing flurbiprofen and lidocaine for dental pain

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    A novel mucoadhesive buccal tablet containing flurbiprofen (FLB) and lidocaine HCl (LID) was prepared to relieve dental pain. Tablet formulations (F1-F9) were prepared using variable quantities of mucoadhesive agents, hydroxypropyl methyl cellulose (HPMC) and sodium alginate (SA). The formulations were evaluated for their physicochemical properties, mucoadhesive strength and mucoadhesion time, swellability index and in vitro release of active agents. Release of both drugs depended on the relative ratio of HPMC:SA. However, mucoadhesive strength and mucoadhesion time were better in formulations, containing higher proportions of HPMC compared to SA. An artificial neural network (ANN) approach was applied to optimise formulations based on known effective parameters (i.e., mucoadhesive strength, mucoadhesion time and drug release), which proved valuable. This study indicates that an effective buccal tablet formulation of flurbiprofen and lidocaine can be prepared via an optimized ANN approach

    Developmental characterization of the microRNA-specific C. elegans Argonautes alg-1 and alg-2.

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    The genes alg-1 and alg-2 (referred to as "alg-1/2") encode the Argonaute proteins affiliated to the microRNA (miRNA) pathway in C. elegans. Bound to miRNAs they form the effector complex that effects post-transcriptional gene silencing. In order to define biological features important to understand the mode of action of these Argonautes, we characterize aspects of these genes during development. We establish that alg-1/2 display an overlapping spatio-temporal expression profile and shared association to a miRNAs set, but with gene-specific predominant expression in various cells and increased relative association to defined miRNAs. Congruent with their spatio-temporal coincidence and regardless of alg-1/2 drastic post-embryonic differences, only loss of both genes leads to embryonic lethality. Embryos without zygotic alg-1/2 predominantly arrest during the morphogenetic process of elongation with defects in the epidermal-muscle attachment structures. Altogether our results highlight similarities and specificities of the alg-1/2 likely to be explained at different cellular and molecular levels

    Role of the microrna pathway in Caenorhabditis elegans germline maintenance

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    Les voies de régulation dépendant des courts ARN non-codants contrôlent plusieurs processus biologiques. Ces courts ARNs sont important dans le développement des cellules germinales de plusieurs espèces ainsi que dans la régulation génique et la résistance virale. Néanmoins, la contribution de la voie de régulation dépendant des microARNs dans la biogénèse des cellules germinales demeure peu comprise. Étant donné que les protéines Argonautes ALG-1 et ALG-2 sont exclusivement impliquées et indispensables à la voie des microARNs, nous avons décidé de manipuler génétiquement ces gènes afin de déterminer si la voie des microARNs est importante dans la prolifération et différentiation des cellules germinales des animaux en utilisant le nématode Caenorhabditis elegans comme modèle d’étude. La perte de fonction des gènes alg-1 et alg-2 rend les animaux stériles, ce qui est similaire aux phénotypes observés chez les nématodes mutant pour Drosha et Dicer (deux enzymes essentielles à la production des microARNs). Ainsi, ceci supporte que la voie de régulation des microARNs joue un rôle essentiel pour le maintien des cellules germinales. Pour définir le rôle précis de ALG-1 et ALG-2 dans les processus complexes de régulation des cellules germinales, nous avons tout d’abord établi la descendance des souches mutantes alg-1(gk214) et alg-2(ok304). Ces deux souches de nématodes ont un faible nombre de descendant qui peut s’expliquer par un problème dans la prolifération des cellules germinales, de méiose ou dans la formation de gamètes. Une analyse précise des gonades de ces animaux indique une plus petite région mitotique avec un nombre de cellules germinales en prolifération inférieur à celui retrouvé chez les animaux de type sauvage. Nous avons aussi observé que les cellules entrent en méiose de manière plus précoce dans les animaux alg-1 et alg-2 mutants, que ces mutants ont des défaut dans la formation de gamètes et qu’ils ont un nombre plus élevé de cellules germinales apoptotiques. En utilisant l’immunofluorescence et des rapporteurs d’expression, nous avons confirmé que ALG-1 et ALG-2 sont exprimées dans la DTC, une cellule spécialisée situé à l’extrémité distale des gonades de C. elegans qui est au cœur de la régulation de la transition mitose-méiose des cellules germinales. En utilisant une lignée transgénique qui exprime ALG-1 exclusivement dans la DTC, nous pouvons partiellement rétablir le nombre de descendants ainsi que rétablir totalement le nombre de cellules retrouvé dans la région mitotique. De façon intéressante, nous observons que la perte de cinq microARNs exprimés dans la DTC mène à des phénotypes similaires à ceux observés dans les mutants alg-1 et alg-2. Finalement, l’analyse de l’expression génique par micropuces des gonades de vers alg-1 mutant indique que la voie des microARNs contribue à la régulation de différentes voies moléculaires importantes pour la prolifération et la différentiation des cellules germinales. L’ensemble de ces études supporte l’implication de la voie des microARNs dans le contrôle de la biogénèse des cellules germinales chez C. elegans.Small non-coding RNA pathways assume pleiotropic roles in the regulation of multitude of biological processes. These non-coding RNAs have been shown to be involved in germline development in diverse species, in addition to their well-known participation in gene regulation and viral resistance pathways. However, the contribution of the miRNA, one of the small non-coding RNA pathways in germline biogenesis has remained elusive. Since ALG-1 and ALG-2 are exclusively involved in the miRNA pathway and indispensible for miRNA mediated gene silencing, we decided to genetically manipulate these genes to address whether miRNA pathway plays an important role in germline proliferation and differentiation using C. elegans as animal model. As double knockout of alg-1 and alg-2 leads to sterility, which mirrors the phenotypes of Drosha and Dicer mutants, we reasoned that the miRNA pathway proteins are crucial in germline maintenance. To delineate the role of ALG-1 and ALG-2 in the complex processes of germline regulation, we first investigated the brood size of alg-1(gk214) and alg-2(ok304) animals. Both mutants had significantly decreased brood size, which could result from defects in germline proliferation, meiosis or gamete formation. An extensive analysis of the germline of these mutants revealed a smaller mitotic region with less number of proliferating germ cells compared to the wild type. We also observed early entry into meiosis in alg-1(gk214) and alg-2(ok304). Using immunofluorescence and transgenic reporters, we confirmed ALG-1 and ALG-2 expression in DTC, a specialized cell located at the tip of both C. elegans gonadal arms that regulates mitosis-meiosis transition. Using transgenic line with alg-1 expressed exclusively in the DTC, we were able to partially rescue the brood size defect and completely restored the number of cells in the mitotic region. These mutants also presented defects in gamete formation and an increase in germ cell apoptosis. Interestingly, we observed that the disruption of five miRNAs expressed in the DTC display similar phenotypes as observed in alg-1 and alg-2 mutants. Finally, gene expression analysis by microarray of alg-1 mutant gonads indicates that the miRNA pathway is involved in the regulation of different pathways important for germline proliferation and differentiation. Together, our data supports the role of miRNA pathway in controlling germline biogenesis in C. elegans

    BIOLOGIE CELLULAIRE ET MOLÉCULAIRE

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    à la Faculté des études supérieures et postdoctorales de l’Université Laval dans le cadre du programme de doctorat en Biologie Cellulaire et Moléculaire pour l’obtention du grade de Philosophie Doctor (Ph.D.

    Skin Lesion Analysis and Cancer Detection Based on Machine/Deep Learning Techniques: A Comprehensive Survey

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    The skin is the human body’s largest organ and its cancer is considered among the most dangerous kinds of cancer. Various pathological variations in the human body can cause abnormal cell growth due to genetic disorders. These changes in human skin cells are very dangerous. Skin cancer slowly develops over further parts of the body and because of the high mortality rate of skin cancer, early diagnosis is essential. The visual checkup and the manual examination of the skin lesions are very tricky for the determination of skin cancer. Considering these concerns, numerous early recognition approaches have been proposed for skin cancer. With the fast progression in computer-aided diagnosis systems, a variety of deep learning, machine learning, and computer vision approaches were merged for the determination of medical samples and uncommon skin lesion samples. This research provides an extensive literature review of the methodologies, techniques, and approaches applied for the examination of skin lesions to date. This survey includes preprocessing, segmentation, feature extraction, selection, and classification approaches for skin cancer recognition. The results of these approaches are very impressive but still, some challenges occur in the analysis of skin lesions because of complex and rare features. Hence, the main objective is to examine the existing techniques utilized in the discovery of skin cancer by finding the obstacle that helps researchers contribute to future research

    Development of an ANN optimized mucoadhesive buccal tablet containing flurbiprofen and lidocaine for dental pain

    No full text
    A novel mucoadhesive buccal tablet containing flurbiprofen (FLB) and lidocaine HCl (LID) was prepared to relieve dental pain. Tablet formulations (F1-F9) were prepared using variable quantities of mucoadhesive agents, hydroxypropyl methyl cellulose (HPMC) and sodium alginate (SA). The formulations were evaluated for their physicochemical properties, mucoadhesive strength and mucoadhesion time, swellability index and in vitro release of active agents. Release of both drugs depended on the relative ratio of HPMC:SA. However, mucoadhesive strength and mucoadhesion time were better in formulations, containing higher proportions of HPMC compared to SA. An artificial neural network (ANN) approach was applied to optimise formulations based on known effective parameters (i.e., mucoadhesive strength, mucoadhesion time and drug release), which proved valuable. This study indicates that an effective buccal tablet formulation of flurbiprofen and lidocaine can be prepared via an optimized ANN approach

    Comparison of allelic imbalance in chromosomes 16 and 17 along with mutation in with -26 GA polymorphism background

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    <p><b>Copyright information:</b></p><p>Taken from "Implication of -26G>A 5' untranslated region polymorphism in susceptibility to sporadic breast cancer and its modulation by codon 72 Arg>Pro polymorphism"</p><p>http://breast-cancer-research.com/content/9/5/R71</p><p>Breast cancer research : BCR 2007;9(5):R71-R71.</p><p>Published online 18 Oct 2007</p><p>PMCID:PMC2242669.</p><p></p> values given are for overall distribution, G/G versus G/A, and A/A versus G/A

    Reporter gene assay with chimeric promoter and 5' untranslated region (UTR) with A or G at the -26 position (upper panel) and the effect of increasing the dose of adriamycin (0, 1, and 2

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    <p><b>Copyright information:</b></p><p>Taken from "Implication of -26G>A 5' untranslated region polymorphism in susceptibility to sporadic breast cancer and its modulation by codon 72 Arg>Pro polymorphism"</p><p>http://breast-cancer-research.com/content/9/5/R71</p><p>Breast cancer research : BCR 2007;9(5):R71-R71.</p><p>Published online 18 Oct 2007</p><p>PMCID:PMC2242669.</p><p></p>5 ÎĽM) (lower panel)
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