59 research outputs found

    Climate change impacts, vulnerability and adaptation: Sustaining rice production in Bangladesh

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    The current study has indicated the most prioritized interventions to be taken against climate change in Bangladeshi rice growing areas prone to drought and salinity events. The suggested methodology managed to evaluate a wide range of agricultural interventions through a transparent and userfriendly approach. The input of stakeholders’ views has provided valuable feedback for the empowerment of the study findings. The presentation of the current policy framework and the ongoing activities in agriculture offers a broad framework on the challenges and constraints to be met upon application of the suggested interventions

    Food Technology Research Institute, Agricultural Research Center, Giza, Egypt

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    Day by day increase the importance of using the natural food additives. Hence in this study, the phenolic extracted from basil leaves, spearmint leaves and fennel seeds, as natural antioxidants, were added at concentrations 200, 400 and 600 ppm from fat weight using in biscuit production. Biscuit was stored at room temperature for 8 months. Induction period was measured by Rancimat apparatus. Total phenolic and phenolic acids were determined. Peroxide value, acid value, thiobarbituric acid and refractive index were measured during storage. Antimicrobial activity of phenolic extraction were examined after 8 months. Sensory evaluation was measured directly after baking. The results showed that total phenolic content in basil leaves, spearmint leaves and fen-nel seeds were 3.97, 1.91 and 1.53 mg/g as caffeic acid equivalents respectively. Five phenolic acids were found in both basil leaves and spearmint leaves, while four phenolic acids were found in fennel seeds as determined by using HPLC. Rancimat results showed that induction period for phenolic herbs could be ranked as follow: basil leaves > spearmint leaves > fennel seeds. The re-sults elucidated that the best concentration from natural additives as antioxidants activity were 400 and 600 ppm compared with BHT. The results revealed that with increasing the concentration of natural antioxidants increased, the more peroxide value, acid value, thiobarbituric acid and refractive index were decreased. Total bacterial count and (yeast & mold) count were decreased with increas-ing the concentration phenolic additives. Sensory evaluation indicated that addition of different anti-oxidants showed no significant differences be-tween control and biscuit sample

    Initial Characterization of the FlgE Hook High Molecular Weight Complex of

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    The spirochete periplasmic flagellum has many unique attributes. One unusual characteristic is the flagellar hook. This structure serves as a universal joint coupling rotation of the membrane-bound motor to the flagellar filament. The hook is comprised of about 120 FlgE monomers, and in most bacteria these structures readily dissociate to monomers (Γ’Λ†ΒΌ 50 kDa) when treated with heat and detergent. However, in spirochetes the FlgE monomers form a large mass of over 250 kDa [referred to as a high molecular weight complex (HMWC)] that is stable to these and other denaturing conditions. In this communication, we examined specific aspects with respect to the formation and structure of this complex. We found that the Lyme disease spirochete Borrelia burgdorferi synthesized the HMWC throughout the in vitro growth cycle, and also in vivo when implanted in dialysis membrane chambers in rats. The HMWC was stable to formic acid, which supports the concept that the stability of the HMWC is dependent on covalent cross-linking of individual FlgE subunits. Mass spectrometry analysis of the HMWC from both wild type periplasmic flagella and polyhooks from a newly constructed ΓŽβ€fliK mutant indicated that other proteins besides FlgE were not covalently joined to the complex, and that FlgE was the sole component of the complex. In addition, mass spectrometry analysis also indicated that the HMWC was composed of a polymer of the FlgE protein with both the N- and C-terminal regions remaining intact. These initial studies set the stage for a detailed characterization of the HMWC. Covalent cross-linking of FlgE with the accompanying formation of the HMWC we propose strengthens the hook structure for optimal spirochete motility

    Real-Time High Resolution 3D Imaging of the Lyme Disease Spirochete Adhering to and Escaping from the Vasculature of a Living Host

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    Pathogenic spirochetes are bacteria that cause a number of emerging and re-emerging diseases worldwide, including syphilis, leptospirosis, relapsing fever, and Lyme borreliosis. They navigate efficiently through dense extracellular matrix and cross the blood–brain barrier by unknown mechanisms. Due to their slender morphology, spirochetes are difficult to visualize by standard light microscopy, impeding studies of their behavior in situ. We engineered a fluorescent infectious strain of Borrelia burgdorferi, the Lyme disease pathogen, which expressed green fluorescent protein (GFP). Real-time 3D and 4D quantitative analysis of fluorescent spirochete dissemination from the microvasculature of living mice at high resolution revealed that dissemination was a multi-stage process that included transient tethering-type associations, short-term dragging interactions, and stationary adhesion. Stationary adhesions and extravasating spirochetes were most commonly observed at endothelial junctions, and translational motility of spirochetes appeared to play an integral role in transendothelial migration. To our knowledge, this is the first report of high resolution 3D and 4D visualization of dissemination of a bacterial pathogen in a living mammalian host, and provides the first direct insight into spirochete dissemination in vivo

    Global Proteome Analysis of Leptospira interrogans

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    Comparative global proteome analyses were performed on Leptospira interrogans serovar Copenhageni grown under conventional in vitro conditions and those mimicking in vivo conditions (iron limitation and serum presence). Proteomic analyses were conducted using iTRAQ and LC-ESI-tandem mass spectrometry complemented with two-dimensional gel electrophoresis and MALDI-TOF mass spec-trometry. A total of 563 proteins were identified in this study. Altered expression of 65 proteins, including upregulation of the L. interrogans virulence factor Loa22 and 5 novel proteins with homology to virulence factors found in other pathogens, was observed between the comparative conditions. Immunoblot analyses confirmed upregulation of 5 of the known or putative virulence factors in L. interrogans exposed to the in vivo-like environmental conditions. Further, ELISA analyses using serum from patients with leptospirosis and immunofluorescence studies performed on liver sections derived from L. interrogans-infected hamsters verified expression of all but one of the identified proteins during infection. These studies, which represent the first documented comparative global proteome analysis of Leptospira, demonstrated proteome alterations under conditions that mimic in vivo infection and allowed for the identification of novel putative L. interrogans virulence factors

    Activation of Human Monocytes by Live Borrelia burgdorferi Generates TLR2-Dependent and -Independent Responses Which Include Induction of IFN-Ξ²

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    It is widely believed that innate immune responses to Borrelia burgdorferi (Bb) are primarily triggered by the spirochete's outer membrane lipoproteins signaling through cell surface TLR1/2. We recently challenged this notion by demonstrating that phagocytosis of live Bb by peripheral blood mononuclear cells (PBMCs) elicited greater production of proinflammatory cytokines than did equivalent bacterial lysates. Using whole genome microarrays, we show herein that, compared to lysates, live spirochetes elicited a more intense and much broader transcriptional response involving genes associated with diverse cellular processes; among these were IFN-Ξ² and a number of interferon-stimulated genes (ISGs), which are not known to result from TLR2 signaling. Using isolated monocytes, we demonstrated that cell activation signals elicited by live Bb result from cell surface interactions and uptake and degradation of organisms within phagosomes. As with PBCMs, live Bb induced markedly greater transcription and secretion of TNF-Ξ±, IL-6, IL-10 and IL-1Ξ² in monocytes than did lysates. Secreted IL-18, which, like IL-1Ξ², also requires cleavage by activated caspase-1, was generated only in response to live Bb. Pro-inflammatory cytokine production by TLR2-deficient murine macrophages was only moderately diminished in response to live Bb but was drastically impaired against lysates; TLR2 deficiency had no significant effect on uptake and degradation of spirochetes. As with PBMCs, live Bb was a much more potent inducer of IFN-Ξ² and ISGs in isolated monocytes than were lysates or a synthetic TLR2 agonist. Collectively, our results indicate that the enhanced innate immune responses of monocytes following phagocytosis of live Bb have both TLR2-dependent and -independent components and that the latter induce transcription of type I IFNs and ISGs

    Callus induction and regeneration of Stevia rebaudiana Bertoni

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    Abstract: Stevia rebaudiana Bertoni is an important non-caloric sweetening herb.It has some kind of diterpenoidsteviol glycosides that had no negative effect on blood sugar level.In the present study, efficient plant regeneration via callus was established. Explants were cultured on MS supplemented with different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) alone and the combination with 1.0 mg/L BA were used to initiate callus. Maximum frequency of callus induction (89%)were observed on MS supplemented with 2.0 mg/L2,4-D.Multiple shoots were obtained on MS medium containing 0.5 mg/L BA and 1.0 mg/LNAA from friable, granule and healthy calli which obtained after 45 days.Regeneration percentage, number of shootlets/ callus part, length of shootlets, number of nodes and number ofleaveswere 86 %, 13.2, 4.36 cm, 4.0 and 8.0, respectively

    Comparative evaluation of curcumin and curcumin loaded- dendrosome nanoparticle effects on the viability of SW480 colon carcinoma and Huh7 hepatoma cells

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    Background and objectives: Colorectal cancer is the third most common cancer and a major cause of morbidity globally. Hepatocellular carcinoma is a leading cause of death in the world. About 80% of all anticancer drugs are somehow related to natural products. One of the most important of these natural compounds is curcumin, the main component of turmeric that has a wide range of pharmacological activities. Curcumin has been found to suppress cell proliferation and decrease cell viability in various types of cancer cells; however, owing to lack of aqueous solubility, curcumin has shown reduced bioavailability in studies. Recent studies have shown that new 400th generation of dendrosome nanoparticle can increase bioavailability of curcumin and thus enhance the cytotoxic properties.Β  The aim of this study was to determine effectiveness of curcumin alone and in combination with 400th generation dendrosome nanoparticles (DNC) on cell viability rate in SW480 and Huh7 cells. Methods: SW480 and Huh7 cells were incubated with different concentrations of curcumin and DNC (0-50ΞΌM) for 24, 48 and 72 h. Then cytotoxicity was assessed by MTT assay and IC50 was determined. Results: The results suggested that the concentration-dependent inhibitory effect of DNC was stronger than curcumin on SW480 and Huh7 cells. Conclusion: The results suggest DNC as a more effective herbal anticancer agent for colorectal and hepatocellular tumors
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