4,571 research outputs found

    IN VITRO SCREENING OF LOCALLY ISOLATED LACTOBACILLUS SPECIES FOR PROBIOTIC PROPERTIES

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    The present study was conducted to determine the probiotic properties of locally isolated lactobacilli in-vitro conditions. For this purpose, intestinal contents (n=20) were collected from crop, gizzard, ileum and caecum of adult healthy chicks and conventional yogurt samples (n=20) were procured from the local market for the isolation of lactobacilli. These samples were mixed homogeneously in sterilized phosphate buffer saline (PBS) separately. Samples from both sources were inoculated on deMan Rogosa and Sharpe (MRS) agar. L. acidophilus 3, L. rhamnosus and L. salivarius were isolated from intestinal contents, while L. delbrucekii ssp bulgaricus and L. paracasei ssp paracasei 1 were isolated from yogurt samples. These lactobacilli were identified through standard API-50 CHL system and then screened for resistance against bile salt, acidic pH, gastric transit and ability to inhibit pathogens as well as survival under different storage temperatures. Tolerance level was found variable (P<0.05) among all the tested species of lactobacillus. All the tested species, except L. delbrucekii and L. paracasei, showed good survival (P<0.05). All lactobacilli inhibited the growth of E. coli and Staphylococcus aureus, except L. delbrucekii that showed significantly (P<0.05) low antimicrobial effect. The results showed that L. acidophilus 3, L. rhamnosus and L. salivarius fulfilled the criteria of in-vitro screening for probiotic properties

    The role of mega projects in redefining housing development in Gulf cities

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    Since the end of the 1990s large scale mega projects have been initiated in Gulf cities to enable an unprecedented urban growth and the expansion of new economic sectors. In this respect, mega projects have played a key role in redefining housing developments in Gulf cities. This paper explores the newly emerging housing typologies and their distinctive roles in defining new urban environments. The selected case studies are located in the Jumeirah District in Dubai, which can be seen as the first prototype of a large cohesive development area that has been built of nine rather differing mega projects including the iconic Palm project and one of the largest residential high-rise agglomerations in the Middle East. The paper is based on the evaluation of official planning data from each project and field observations. Conclusions are drawn to highlight key implications while identifying housing development tendencies

    Migrant Knowledge Workers’ Perceptions of Housing Conditions in Gulf Cities

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    © 2017, The Author(s). The various efforts in diversifying local economies in most Gulf States led to the emergence of new medium to high-income groups of migrant knowledge workers whose efforts are required to develop various new economic sectors. This paper aims to investigate the current housing conditions and perceptions of these migrant communities to identify key similarities and differences with respect to housing made available to them and depending on their cultural background. To this end, the methodology involves field surveys to explore the three main housing typologies for higher-income groups and a questionnaire with a total of 258 knowledge workers in the city of Doha as a representative case to investigate the associated perceptions of four dominant groups from different cultural backgrounds. The findings reveal that there is a distinct social segregation between cultural groups, which is mainly rooted in varying income levels. Furthermore, the supply-driven market has hardly integrated cultural needs of migrants and thus diversified and inclusive housing has been identified as major planning and design challenge

    Recent Advances In Stimuli-Responsive Drug release and targeting concepts using mesoporous silica nanoparticles

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    Being a developed and promising approach, nanotechnology has attracted a lot of attention in biomedical and pharmaceutical therapy applications. Among nanostructured materials, mesoporous silica nanoparticles (MSNs) are effectively used as nanocarriers for drug delivery systems. MSNs can be tailored-designed by different synthetic techniques. Their morphological characteristics dictate the type of application of such materials. Recently, polymer-based materials have been employed to functionalize the MSNs surface. These modified nanocarriers are loaded with the drug and can unload their “cargo” upon exposure to either endogenous or exogenous types of stimuli. In this study, different targeting concepts, including passive, active, vascular, nuclear, and multistage targeting, are discussed

    A chronological exploration of the evolution of housing typologies in Gulf cities

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    This paper traces the evolution of housing typologies in four major cities in the Gulf region, namely Doha, Dubai, Abu Dhabi and Manama. The study reviews the formation and historical events in the region, which had a significant impact on new social as well as economic realities and consequently evolving housing types during the last two centuries. The methodological approach is based on reviewing a number of case studies representing local housing typologies throughout distinctive historic periods which were categorized in four periods: the post-nomadic, traditional, modern, and contemporary. The main objective is to identify the process of transformation by applying a comparative assessment of the different periods in order to examine continuities or ruptures between them. Thus, particular layout elements were analysed and compared. Conclusions are drawn to underline contemporary challenges while offering projections for future housing typologies in the selected cities and other similar ones

    Calli Essential Oils Synergize with Lawsone against Multidrug Resistant Pathogens.

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    The fast development of multi-drug resistant (MDR) organisms increasingly threatens global health and well-being. Plant natural products have been known for centuries as alternative medicines that can possess pharmacological characteristics, including antimicrobial activities. The antimicrobial activities of essential oil (Calli oil) extracted from the Calligonum comosum plant by hydro-steam distillation was tested either alone or when combined with lawsone, a henna plant naphthoquinone, against MDR microbes. Lawsone showed significant antimicrobial activities against MDR pathogens in the range of 200-300 µg/mL. Furthermore, Calli oil showed significant antimicrobial activities against MDR bacteria in the range of 180-200 µg/mL, Candida at 220-240 µg/mL and spore-forming Rhizopus fungus at 250 µg/mL. Calli oil's inhibition effect on Rhizopus, the major cause of the lethal infection mucormycosis, stands for 72 h, followed by an extended irreversible white sporulation effect. The combination of Calli oil with lawsone enhanced the antimicrobial activities of each individual alone by at least three-fold, while incorporation of both natural products in a liposome reduced their toxicity by four- to eight-fold, while maintaining the augmented efficacy of the combination treatment. We map the antimicrobial activity of Calli oil to its major component, a benzaldehyde derivative. The findings from this study demonstrate that formulations containing essential oils have the potential in the future to overcome antimicrobial resistance

    Sheared bioconvection in a horizontal tube

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    The recent interest in using microorganisms for biofuels is motivation enough to study bioconvection and cell dispersion in tubes subject to imposed flow. To optimize light and nutrient uptake, many microorganisms swim in directions biased by environmental cues (e.g. phototaxis in algae and chemotaxis in bacteria). Such taxes inevitably lead to accumulations of cells, which, as many microorganisms have a density different to the fluid, can induce hydrodynamic instabilites. The large-scale fluid flow and spectacular patterns that arise are termed bioconvection. However, the extent to which bioconvection is affected or suppressed by an imposed fluid flow, and how bioconvection influences the mean flow profile and cell transport are open questions. This experimental study is the first to address these issues by quantifying the patterns due to suspensions of the gravitactic and gyrotactic green biflagellate alga Chlamydomonas in horizontal tubes subject to an imposed flow. With no flow, the dependence of the dominant pattern wavelength at pattern onset on cell concentration is established for three different tube diameters. For small imposed flows, the vertical plumes of cells are observed merely to bow in the direction of flow. For sufficiently high flow rates, the plumes progressively fragment into piecewise linear diagonal plumes, unexpectedly inclined at constant angles and translating at fixed speeds. The pattern wavelength generally grows with flow rate, with transitions at critical rates that depend on concentration. Even at high imposed flow rates, bioconvection is not wholly suppressed and perturbs the flow field.Comment: 19 pages, 9 figures, published version available at http://iopscience.iop.org/1478-3975/7/4/04600

    Metadherin mRNA expression in hepatocellular carcinoma

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    Background: Metadherin (MTDH) has been known as an essential oncogene in carcinogenesis and tumor spread in several malignancies, via its effect on pathways of signal transduction.Objective: We aimed to evaluate the role of serum MTDH mRNA expression in the diagnosis of hepatocellular carcinoma (HCC) and to compare its expression levels with serum levels of Alpha-fetoprotein (AFP).Subjects &amp; methods: A total of 150 subjects (90 HCC patients &amp; 60 healthy volunteers) were enrolled in the current study. Serum MTDH mRNA relative expression was analyzed by Real Time PCR technique.Results: There was a significant statistical increase of serum MTDH mRNA expression in HCC group when compared to controls (P &lt; 0.05). MTDH mRNA expression was significantly associated with clinicopathological data, advanced tumor stage and poor histological differentiation in HCC patients (p &lt; 0.05). There was direct positive correlation between MTDH mRNA expression and serum AFP levels in HCC group (r = 0.445), P value = &lt;0.05. ROC curve was used to verify the accuracy of MTDH mRNA expression and compare it with accuracy of serum AFP in HCC diagnosis; MTDH mRNA expression had higher accuracy (92%), sensitivity (91%) and specificity (93%) than AFP.Conclusion: MTDH mRNA is up-regulated in serum of HCC patients; MTDH may be considered as noninvasive biomarker for HCC diagnosis and it could replace serum AFP in HCC diagnosis as it had higher accuracy.Keywords: Biomarker, Expression, Hepatocellular carcinoma, Metadherin, Real Time PC
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