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Selected AbstractsrpoB -PCR amplified gene and temporal temperature gradient gel electrophoresis: a rapid tool to analyse bacterial strains representative of cold-smoked salmon microfloraLETTERS IN APPLIED MICROBIOLOGY, Issue 2 2004S. Giacomazzi Abstract Aim:, To evaluate rpoB gene as a biomarker of microbial biodiversity associated to cold-smoked salmon by a novel nested-polymerase chain reaction/temporal temperature gradient gel electrophoresis (PCR/TTGE) technique applied on pure cultures of reference strains. Methods and Results:, DNA obtained from pure cultures of reference strains was used in a succession of a first PCR amplification of rpoB fragment with degenerated nonclamped primers and a nested-PCR with nondegenerated clamped primers. PCR products were then applied on a TTGE gel in order to analyse strains profile. High quantity of nested-PCR products were obtained for each tested strain and TTGE profiles showed a good separation between the different reference bacteria and an easy way to associate one band to one species. Conclusion:, The nested-PCR/TTGE technique used in this study is a promising way of investigating bacterial community structure of cold-smoked salmon or other food matrix. Significance and Impact of the Study:, Because of its single copy state leading to single band profiles in TTGE, rpoB constitute a good potential molecular marker for further development of cold-smoked salmon biodiversity analysis. [source] Peptides of human gingival crevicular fluid determined by HPLC-ESI-MSEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 6 2005Elisabetta Pisano The acidic-soluble protein content of human gingival crevicular fluid was analyzed by reverse-phase high-performance liquid chromatography (RP-HPLC), and the eluent deriving from the chromatography separation was directly introduced into an ion-trap mass spectrometer through electrospray ionization (ESI-IT MS). By this technique the molecular weight of peptides/proteins was determined with a precision of ,,1/10,000 amu. On the basis of the chromatographic behavior and the knowledge of the molecular mass value, some peptides and proteins soluble in acidic solution were unambiguously recognized. Besides high quantities of human serum albumin, , -defensins 1,4 and minor amounts of cystatin A, statherin, basic PB salivary peptide and other unidentified components were detected. The presence of , -defensins in gingival crevicular fluid is in agreement with their relevant contribution to protein composition deriving from granulocyte secretions. Other peptides and proteins abundant in human saliva, such as proline-rich proteins (PRPs) and histatins, were not detected in gingival crevicular fluid. Further investigations will be necessary to establish the origin of statherin and PB salivary peptide in gingival crevicular fluid. [source] Effects of different brush border membrane vesicle isolation protocols on proteomic analysis of Cry1Ac binding proteins from the midgut of Helicoverpa armigeraINSECT SCIENCE, Issue 6 2008Li-Zhen Chen Abstract Brush border membrane vesicles (BBMV) isolated from insect midguts have been widely used to study Cry1A binding proteins. Sample preparation is important in two-dimensional electrophoresis (2-DE), so to determine a suitable BBMV preparation method in Helicoverpa armigera for 2-DE, we compared three published BBMV preparation methods mostly used in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). All methods yielded similar types and numbers of binding proteins, but in different quantities. The Abdul-Rauf and Ellar protocol was the best of the three, but had limitations. Sufficient protein quantity is important for research involving limited numbers of insects, such as studies of insect resistance to Bacillus thuringiensis in the field. Consequently, we integrated the three BBMV isolation methods into a single protocol that yielded high quantities of BBMV proteins from H. armigera larval midguts, which proved suitable for 2-DE analysis. [source] Biodesulfurization of dibenzothiophene using recombinant Pseudomonas strainJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 3 2008Lavanya Meesala Abstract BACKGROUND: The sulfur content in crude oil available from various sources ranges from 0.03 to values as high as 8.0 wt%. These high quantities of sulfur must be removed before the crude oil is processed because combustion of this oil would result in severe environmental pollution, such as acid rain. Due to high utility and operating costs, the conventional hydrodesulfurization process (HDS) is considered to be uneconomic. The biotechnological option, biodesulfurization (BDS) seems an attractive low cost, environmentally benign technology. RESULTS: This paper reports the development of a recombinant strain of bacteria designed by introducing desulfurizing, dsz genes containing plasmid pSAD 225-32, which was isolated from Rhodococcus erythropolis IGTS8 into a gram negative solvent-tolerant bacterium, Pseudomonas putida (MTCC 1194). This recombinant bacterium can desulfurize the dibenzothiophene (DBT) in the sulfur selective 4S-pathway. It has been observed that for the same concentration of DBT, the recombinant strain's growth rate is greater than that of the parent strain. Increasing the concentration of DBT resulted in an increase of lag phase as well as decreased growth rate, which shows that the bacteria is following substrate inhibition type kinetics. This genetically modified bacterium can desulfurize 73.1% of 1.2 mmol L,1 DBT (dissolved in ethanol) in 67 h of cultivation time using growing cells. CONCLUSIONS: It is concluded that further research in this area of biodesulfurization using genetically modified organisms may remove the bottlenecks presently in the way of commercialization of the BDS process. Copyright © 2007 Society of Chemical Industry [source] Improvement of a fed-batch process for high level xylanase production by a Bacillus strainJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 5 2001Gerhard Schneider Abstract In this paper, the improvement of a fed-batch fermentation from the point of view of an industrial xylanase production process is described. The Bacillus strain chosen for this study is able to produce high quantities of a xylanase that is suitable to be used as bleach boost agent in chlorine-free bleaching sequences of paper pulp. It was found that xylo-oligosaccharides (hydrolysis products from xylan by xylanase action) were indispensable for induction of the enzyme synthesis, but that their presence in quantities of only 0.1,g,dm,3 xylose equivalents led to catabolite repression. A substrate-limited fed-batch process, that is the most adapted, was furthermore improved with regard to nutrient requirement of the microorganism, especially the nitrogen source. A process with constant supply of a culture medium containing xylan, peptone and mineral nitrogen was able to produce 20,240,nkat,cm,3 with a productivity of 910,nkat,cm,3,h,1, which places the process among the best ever reported. © 2001 Society of Chemical Industry [source] Formation of complexes between uracil and calcium ions: an ESI/MS/MS study in combination with theoretical calculationsJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 5 2009Emilie-Laure Zins Abstract Cationized uracil clusters around calcium metal ions were generated in the gas phase by electrospray ionization (ESI). A previous study showed that with particular experimental conditions, hexamer, octamer, decamer, dodecamer and tetradecamer uracil clusters are present in high quantities. New experiments were carried out to understand the reasons for the particular stability of these complexes. MS/MS experiments suggested that these uracil clusters belong to the same family. Based on ab initio and DFT quantum chemistry calculations, structures in agreement with experimental results are proposed for these clusters. Copyright © 2009 John Wiley & Sons, Ltd. [source] Sulfoalkyl ether-alkyl ether cyclodextrin derivatives, their synthesis, NMR characterization, and binding of 6,-methylprednisoloneJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 11 2005Serena Tongiani Abstract The objective of this study is to see if random alkyl ethers of various sulfoalkyl ether cyclodextrins can be synthesized and characterized. The purpose of the alkylation was to test the hypothesis that an increase in the "height" of a cyclodextrins cavity would help in the binding/complexation of larger more structurally complex molecules. The synthesis of new cyclodextrin derivatives comprising a mixture of sulfoalkyl ether and alkyl ether substituents on the same cyclodextrin ring was performed in aqueous alkaline solutions using various sultones and alkylsulfates. The method presented provided an easy and efficient way to modify cyclodextrins avoiding the use of organic solvents and high quantities of alkylating agents and could be carried out in either a two step or "one pot" single step process. Purification was by neutralization followed by ultrafiltration. The derivatives were characterized by 1D, (1H and 13C), and a 2D NMR technique (HMQC, Heteronuclear Multiple Quantum Coherence). The combination of these techniques allowed an analysis of the degree of substitution and the site of substitution on the cyclodextrin (CD) nucleus. For both ,- and ,-CD, sulfoakylation was preferred on the 2,>,3,>,6 hydroxyls while alkylation was preferred 6,>,2,>,3. Due to the simultaneous presence of short alkyl ether chains and negatively charged sulfoalkyl ether chains, these mixed water-soluble cyclodextrin derivatives, especially those of ,-cyclodextrin, should be able to bind more complex drugs. The improved binding capacity of these new modified CDs with the model drug 6,-methylprednisolone is reported. © 2005 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 94:2380-2392, 2005 [source] Morphology and fracture properties relationship of epoxy-diamine systems simultaneously modified with polysulfone and poly(ether imide)POLYMER ENGINEERING & SCIENCE, Issue 9 2005M.I. Giannotti An epoxy-diamine system was simultaneously modified with two immiscible thermoplastic polymers, polysulfone (PSF) and poly (ether imide) (PEI), to develop tough materials without adding high quantities of modifiers, in order to avoid the processibility problems caused by the high initial viscosity of the mixtures. The mechanical behavior of blends containing 10 and 15 wt% total thermoplastic was analyzed and compared with the generated morphologies. The scanning electron micrographs (SEM) of the broken surfaces showed that when a small part of PEI is replaced by PSF, drastic changes in morphology, leading to co-continuity between the phases, occurred together with fracture (critical stress intensity factor, KIC) improvements. As an additional advantage, no noticeable decrease in the elastic modulus (E) of final materials was observed. POLYM. ENG. SCI., 45:1312,1318, 2005. © 2005 Society of Plastics Engineers [source] Monthly assessments of proteins, fatty acids and amino acids in Artemia franciscana cultivated in ,Las Salinas de Hidalgo', state of San Luis Potosí, MexicoAQUACULTURE NUTRITION, Issue 2 2009T. CASTRO Abstract This study presents the biochemical contents of Artemia biomass produced in a pond in ,Las Salinas de Hidalgo', State of San Luis Potosí, Mexico. The culture was realized over a period of 1 year in an 80 × 50 × 0.65 m (200 m3) pond. The feed consisted of a mixture of four micro algae. Samples of 1 kg of Artemia biomass (wet basis) were taken monthly and total protein, total lipid, amino acids and fatty acids were assessed. The contents of total protein and lipids showed a similar tendency from July to December (maintained values of about 300 mg g,1 for protein and 90 mg g,1 for lipids). With the exception of methionine and arginine, other seven indispensable amino acids were detected in the monthly samples, having similar values during the period from July to December. The most common fatty acids determined were the C16, C18, C18:1 and C18:3n6. Both, C20:4n6 and C20:5n3, were observed occasionally, but in high quantities. The use of the four micro algae as food for the Artemia cultured extensively, improved the biochemical composition and allows using this crustacean as feed for several species of aquatic organisms used for ornamental or human consumption. [source] Interactions of T helper cells with fibroblast-like synoviocytes: Up-regulation of matrix metalloproteinases by macrophage migration inhibitory factor from both Th1 and Th2 cellsARTHRITIS & RHEUMATISM, Issue 10 2008Uta Schurigt Objective Interactions of immune cells, such as activated T helper cells, with fibroblast-like synoviocytes (FLS) play a crucial role in the joint destruction during human rheumatoid arthritis (RA). This study was undertaken to investigate the expression of the proinflammatory cytokine macrophage migration inhibitory factor (MIF) by T helper cells, and to assess the role of MIF in overexpression of matrix metalloproteinases (MMPs) in cocultures of FLS from arthritic mice with either Th1 or Th2 cells. Methods MIF expression by in vitro,polarized murine Th1 and Th2 cells was determined using 2 different generation protocols. FLS were isolated from the inflamed joints of mice with antigen-induced arthritis. MMP expression was analyzed in cocultures of the FLS with T helper cell subsets. Effects of MIF were blocked by a neutralizing anti-MIF antibody. In addition, analyses were performed on cocultures of either Th1 or Th2 cells with FLS from MIF-deficient mice. Results Both Th1 and Th2 cells expressed high quantities of MIF. MMPs were overexpressed by FLS after coculture with both Th1 and Th2 cells. Activated T helper cells were more effective than resting cells. Neutralization of MIF by an anti-MIF antibody led to a marked reduction in MMP expression in Th1- and Th2-stimulated FLS. T helper cells generated from MIF-deficient mice exhibited a T helper cell,specific cytokine profile comparable with that in wild-type cells, except in the expression of MIF, but showed an impaired ability to stimulate MMP expression in FLS. Conclusion MIF is an important Th1 and Th2 cell,derived proinflammatory cytokine that stimulates MMP expression in FLS from arthritic mice, and therefore inhibition of MIF might be a promising target for novel therapeutic strategies in human RA. [source] The absorption, distribution, metabolism and elimination of bevirimat in ratsBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 7 2008Peter Bullock Abstract Bevirimat is the first drug in the class of maturation inhibitors, which treat HIV infection by disrupting the activity of HIV protease enzyme with a mechanism of action distinct from that of conventional protease inhibitors. The absorption, distribution, metabolism and elimination characteristics of single intravenous (25,mg/kg) and oral (25,mg/kg and 600,mg/kg) doses of 14C-bevirimat were studied in male Sprague Dawley and Long Evans rats. Pharmacokinetic and mass-balance studies revealed that bevirimat was cleared rapidly (within 12,24,h) after dosing, although plasma radioactivity was quantifiable up to 168,h. Radioactive metabolites of bevirimat were responsible for approximately 60,80% of plasma radioactivity. Systemically available bevirimat was predominantly (97%) excreted via bile in the faeces, with ,1% of the dose excreted renally. Less than 0.1% of the dose was excreted in expired air. Quantitative whole-body autoradiography detected high quantities of radioactivity in the bile and liver soon after intravenous dose administration, and evidence of biliary excretion present during the 8,h following oral dosing. Oral bioavailability for the 25,mg/kg dose of bevirimat was estimated at 22,24% by pharmacokinetic and mass-balance methods, with bioavailability decreasing disproportionately with increasing dose for the 600,mg/kg group. Copyright © 2008 John Wiley & Sons, Ltd. [source] Significance of the KlLAC1 gene in glucosylceramide production by Kluyveromyces lactisFEMS YEAST RESEARCH, Issue 6 2008Naoya Takakuwa Abstract Each of the 12 genes involved in the synthesis of glucosylceramide was overexpressed in cells of Kluyveromyces lactis to construct a strain accumulating a high quantity of glucosylceramide. Glucosylceramide was doubled by the KlLAC1 gene, which encodes ceramide synthase, and not by 11 other genes, including the KlLAG1 gene, a homologue of KlLAC1. Disruption of the KlLAC1 gene reduced the content below the detection level. Heterologous expression of the KlLAC1 gene in the cells of Saccharomyces cerevisiae caused the accumulation of ceramide, composed of C18 fatty acid. The KlLAC1 protein preferred long-chain (C18) fatty acids to very-long-chain (C26) fatty acids for condensation with sphingoid bases and seemed to supply a ceramide moiety as the substrate for the formation of glucosylceramide. When the amino acid sequences of ceramide synthase derived from eight yeast species were compared, LAC1 proteins from five species producing glucosylceramide were clearly discriminated from those of the other three species and all LAG1 proteins. The LAC1 protein of K. lactis is the enzyme that plays a crucial role in the synthesis of glucosylceramide. [source] Nutritional variables related to gingival health in adolescent girlsCOMMUNITY DENTISTRY AND ORAL EPIDEMIOLOGY, Issue 6 2000Stefano Petti Abstract , In order to study the nutritional variables associated with gingival health, a case-control study was designed to control strong variables whose effect on gingival status may obscure the potential effect of weaker ones, such as nutrition. Two groups of 27 gingivitis-affected and -unaffected female adolescents were selected. All were aged 17,19 years, with mean age of the two groups statistically not different. All were non-smokers, all reported daily toothbrushing frequency of twice/day or more, and none had clinical signs of hyponutrition. Mean DMFT of the two groups was statistically not different. The effect of nutritional variables, obtained by a three-day food record and by assessing the nutritional status of the girls, on presence/absence of gingivitis was evaluated by a variety of stepwise logistic regression analyses. Age (positive correlation), riboflavin, calcium and frequency of fibre intake (negative correlations) significantly explained the risk for gingivitis. Strong intercorrelation between riboflavin and calcium was also found, due to the high quantity of milk consumed by the girls, since this food provided the main source of riboflavin and calcium. The data suggest that some dietary measures may be useful for the maintenance of healthy gingival status. [source] Hydrogenation for Low Trans and High Conjugated Fatty AcidsCOMPREHENSIVE REVIEWS IN FOOD SCIENCE AND FOOD SAFETY, Issue 1 2005Eun Seok Jang ABSTRACT Hydrogenated vegetable oils contain of trans fatty acids. Because of the increased health concern about trans fatty acids, new hydrogenations have been studied to seek ways for substantial reduction of the trans fatty acids in the hydrogenated vegetable oils. This paper reviews new hydrogenation processes such as electrocatalytic hydrogenation, precious catalyst hydrogenation, and supercritical fluid state hydrogen, which have shown promising results for the reduction of trans fatty acids below the level of 8%. This paper also reviews the recently introduced hydeogenation technique for high accumulation of conjugated linoleic acids, beneficiary functional components. The hydrogenated vegetable oils with high quantity conjugated linoleic acid might provide the possibility for the utilization of hydrogenated oils as health-prompting food ingredients. [source] | ||||||||||||||||