• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2003.06a
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• pp.124-124
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• 2003

• Microbiology and Biotechnology Letters
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• v.49 no.4
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• pp.501-509
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• 2021

The increasing demand for baked products has given a boost to research on isolation and selection of novel yeast strains with improved leavening activity. Twelve sourdough samples were collected from several localities of the Fez region in Morocco. The pH and total titratable acidity (TTA) values of these samples varied from 3.03-4.63 and 14-17.5 ml of 0.1 N NaOH/10 g of sourdough, respectively, while yeast counts ranged from 5.3 6.77 Log CFU/g. Thirty-two yeast isolates were obtained and evaluated for their leavening ability. Out of all isolates, four yeasts molecularly identified as Saccharomyces cerevisiae (three strains) and Kluyveromyces marxianus (one strain) showed highest specific volumes of 4.69, 4.55, 4.35 and 4.1 cm³/g, respectively. These strains were further assessed for their tolerance to high concentrations of salt, sugar, elevated temperatures, and low pH conditions. K. marxianus showed higher resistance than the S. cerevisiae. Thus, Moroccan sourdoughs harbor technologically relevant yeasts that could be used as potential starters for bread preparation.

• Molecules and Cells
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• v.44 no.8
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• pp.549-556
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• 2021

Decoding the molecular mechanisms underlying axon guidance is key to precise understanding of how complex neural circuits form during neural development. Although substantial progress has been made over the last three decades in identifying numerous axon guidance molecules and their functional roles, little is known about how these guidance molecules collaborate to steer growth cones to their correct targets. Recent studies in Drosophila point to the importance of the combinatorial action of guidance molecules, and further show that selective fasciculation and defasciculation at specific choice points serve as a fundamental strategy for motor axon guidance. Here, I discuss how attractive and repulsive guidance cues cooperate to ensure the recognition of specific choice points that are inextricably linked to selective fasciculation and defasciculation, and correct pathfinding decision-making.

• Journal of Pharmaceutical Investigation
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• v.36 no.6
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• pp.355-361
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• 2006

Intraarticular corticosteroid injections for therapy of rheumatic arthritis are administered with the aim of optimal local anti-inflammatory effect at the injection site. Since the side effects of corticosteroidal drug, dexamethasone(DEX), administered at hish dose limited the therapeutic efficacy, there was a need to design a new drug delivery system for controlled release of dexamethasone. As a prodrug for continuous therapeutic efficacy, dexamethasone-21-palmitate(DEX-PAL) was prepared via esterification of palmitoyl chloride and dexamethasone. DEX-PAL was identified by NMR and MASS analysis. DEX-PAL or DEX was entrapped in lipid nanosphere which could be prepared by using a self emulsification-solvent evaporation method. Physicochemical characteristics such as mean particle diameter, zeta potential and drug loading efficiency of the lipid nanospheres were investigated with variation of either the kind of lipid or the lipid composition. The lipid nanospheres had a mean diameter $83{\sim}95$ nm and DEX-PAL loading efficiency of up to 95%. The drug loading efficiency increased with the increase of aliphatic chain length attached to the phospholipid. The incorporation of cationic lipid was very efficient for both reducing particle size of lipid nanospheres and enhancing drug loading efficiency. The lipid nanospheres containing DEX-PAL may be a promising novel drug carrier for the controlled release of the poorly water-soluble drugs.

• Nuclear Engineering and Technology
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• v.34 no.2
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• pp.146-153
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• 2002

To radiolabel bioactive molecules, we synthesized $^{99m}$Tc-tricarbonyl precursor, [$^{99m}$Tc(CO)$_3$($H_2O$)$_3$]$^{+}$ with a low oxidation state ( I ). The [$^{99m}$Tc(CO)$_3$($H_2O$)$_3$]$^{+}$ was prepared by low pressure carbonylation (1 atm of CO) of [$^{99m}$Tc $O_4$)]$^{[-10]}$ in the presence of NaB $H_4$ resulting in higher than 98% of labeling yield and stability up to 8 hrs. We evaluated the characteristics of $^{99m}$Tc- tricarbonyl labeled bioactive molecules by carrying out in vitro and in vitro study. Prepared [$^{99m}$Tc(CO)$_3$($H_2O$)$_3$]$^{+}$ was then reacted with some ligands of significance in modem diagnostic nuclear medicine and some amino acids. Labeling yields were checked by HPLC and found to be usually high, excluding $^{99m}$Tc-tricarbonyl-MDP, -EDTMP and -mIBG. And the biodistribution properties of $^{99m}$Tc-tricarbonyl complexes applied in rabbit showed different appearance comparing with that of the $^{99m}$Tc-labeling by conventional means. From these results, we conclude that [$^{99m}$Tc(CO)$_3$($H_2O$)$_3$]$^{+}$ is a potential precursor for development of radiopharmaceuticals, especially for labeling of biomolecules.

• Journal of Dairy Science and Biotechnology
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• v.32 no.2
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• pp.141-145
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• 2014

There is a burgeoning number of products on the market that contain probiotics, but do they do you any good? What exactly are probiotics? They have been defined as living organisms that, when ingested in sufficient quantities, provide health benefits beyond basic nutrition. They are often referred to as "friendly bacteria" or "good bacteria." Probiotics have been claimed, amongst other things, to (i) reduce the incidence of colon cancer and other diseases of the colon, such as IBS, (ii) stimulate the immune system, (iii) have anti-hypertensive and anti-cholesterolemic properties, (iv) mitigate against the effect of antibiotics on the intestinal microbiota, and (v) protect against gastrointestinal infections. However, the scientific basis for many of these claims is not well-established. Indeed, the European Food Safety Authority has denied the use of several health claims associated with probiotics, particularly those related to mitigation of diarrhea following consumption of antibiotics. Thus, there is a need for research on the mechanisms of action of probiotics. We have been mainly interested in the use of probiotics to control enteric infections. There are several possible modes of action to explain how probiotics may protect the host from enteric pathogens, including competitive exclusion and immunomodulation. We have shown that probiotics produce bioactive molecules that interfere with bacterial cell-cell communication (also called quorum sensing), and this results in a down-regulation of virulence genes that are responsible for attachment of the pathogen to the gastrointestinal epithelium. These bioactive molecules act on a variety of bacteria, including enterohemorrhagic and enterotoxigenic Escherichia coli, Salmonella, Clostridium difficile and Clostridium perfringens, and there is evidence that they can inhibit the formation of biofilms by Listeria monocytogenes. These bioactive molecules, which are peptidic in nature, can exert their effects not only in vitro but also in vivo, and we have shown that they mitigate against E. coli O157:H7 and Salmonella in mice and Salmonella and E. coli K88 infections in pigs. They can be delivered in foods such as yoghurt and maintain their activity.

• Korean Journal of Pharmacognosy
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• v.21 no.1
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• pp.1-48
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• 1990

Marine organisms have proven to be rich sources of interesting organic molecules. A great number of compounds with diverse structural features and interesting biological activities have been isolated. Recent studies on secondary metabolites of marine organisms are discussed with a focus on a variety of biological activities and marine natural product literatures are also reviewed.

• Journal of Integrative Natural Science
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• v.17 no.2
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• pp.59-65
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• 2024

Dendritic cells play a very important role in the immune response as antigen-presenting cells that are critical for initiating both innate and acquired immunity. They recognize, process and present foreign antigens to other key immune cells to trigger and regulate the immune response. The ability to activate these dendritic cells can be used as a treatment for various immune diseases. Maqui berry has been reported to have anticancer, antibacterial and anti-inflammatory properties. However, its effect on the activity of dendritic cells has not been studied. In this study, we investigated the efficacy of maqui berry extract in modulating dendritic cell activity. Treatment of dendritic cells with maqui berry extract induced the costimulatory molecules CD80, CD86, and MHC class I and II in a concentration-dependent manner. Furthermore, the antigen-presenting capacity of dendritic cells was inhibited, which confirms their ability to present antigens, and the production of Interleukin (IL)-12, which is important for dendritic cell activity, was increased. These results indicated that Maqui berry extract activates dendritic cells maturation by inducing the production of co-stimulatory molecules and IL-12. These results suggest that maqui berry extract may act as an effective adjuvant to enhance dendritic cell-based immune responses.

• Journal of Marine Bioscience and Biotechnology
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• v.5 no.4
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• pp.15-25
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• 2011

Marine sponges are a rich source of highly diversified bioactive compounds. These medicinally valuable molecules represent extreme physiological and ecological functions in sponges, more presumably involving in the resistance to the feeding by other marine organisms like fish and fouling by barnacles, bacteria, fungi, etc. This feature of attaining resistance made sponges as successful poriferans that possess an impressive array of biological properties ranging from antimicrobial to anticancerous activities. The diversified bioactive principle of sponges might be due to their spacio-temporal distribution and although, the gateway for exploiting the sponges for isolating these distinct, potential molecules is open, suitable technical and methodological approaches are yet to be implemented in order to bring the sponges as successful pharmaceutical leads in the field of marine biotechnology. Despite of the identified difficulties of marine sponge research from past few decades, one should concentrate not only on the basic and applied technical/methodological considerations, but also on the novel strategies like in vitro sponge cell, fragment and whole sponge culture; sponge symbiont cell culture; in situ and ex situ sponge cultivation; and sponge bioreactors and metagenomic approaches, for the successful exploitation of marine sponges towards the novelty in sponge biotechnology. The present review narrates the pros and cons of the nowadays-marine sponge research by focusing on the suggestive ecobiotechnological approaches, based on the latest studies for feasible ecological exploitation and biotechnological application of sponges from the sea.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.365.3-366
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• 2002

New and improved preparations of structurally modified nucleosides are important goals in synthetic organic chemistry because of the potential utility of these compounds as synthetic precursors of many biologically active molecules in cells. In our program to synthesize the bioactive nucleosides, such as AdoHcy hydrolase inhibitors and cyclic adenosine diphosphoribose(cADPR) analogues. (omitted)