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Decreasing Order (decreasing + order)
Selected AbstractsEffect of temperature and storage media on human periodontal ligament fibroblast viabilityDENTAL TRAUMATOLOGY, Issue 3 2010Beatriz Dulcineia Mendes Souza The purpose of this study was to compare the effectiveness of several storage media to preserve cultured periodontal ligament fibroblasts (PDLF) under different temperatures. The media tested were: sterile Hank's balanced salt solution (sHBSS), non-sterile HBSS (nHBSS), skimmed milk, Save-A-Tooth®, Minimum Essential Medium (MEM) and water (negative control). MEM at 37°C was used as positive control. PDLF were obtained from explants of extracted healthy human teeth. Plates containing confluent PDLF were soaked in the various media for 3, 6, 24, 48 and 72 h at 37°C and 20°C. After incubation, viability of the cells was determined using the tetrazolium salt-based colorimetric (MTT) assay and the Trypan Blue exclusion test after 6, 24, 48 and 72 h of incubation at 20°C. The results were analyzed statistically using Kruskal,Wallis, Scheffé and Mann,Whitney (, = 5%) tests. Results from the MTT assay at 37°C and 20°C showed that skimmed milk was the best storage medium for up to 24 and 48 h, respectively, followed by nHBSS and sHBSS. Results from the Trypan Blue exclusion test showed that the best storage media were milk, sHBSS and nHBSS, with no statistical differences, for any time period. The Save-A-Tooth® had a detrimental effect on cells after 24 h. The influence of temperature on the effectiveness of the storage media tested showed at 20°C a decreasing order of efficacy as follows: milk > sHBSS and nHBSS > MEM > Save-A-Tooth® > water while at 37°C it was: MEM > nHBSS > milk > sHBSS > Save-A-Tooth® > water. In conclusion, incubation temperature altered the effectiveness of the storage media and skimmed milk at 20°C was better than HBSS in maintaining PDLF viability. [source] Dinucleoside polyphosphates stimulate the primer independent synthesis of poly(A) catalyzed by yeast poly(A) polymeraseFEBS JOURNAL, Issue 21 2002María A. Günther Sillero Novel properties of the primer independent synthesis of poly(A), catalyzed by the yeast poly(A) polymerase are presented. The commercial enzyme from yeast, in contrast to the enzyme from Escherichia coli, is unable to adenylate the 3,-OH end of nucleosides, nucleotides or dinucleoside polyphosphates (NpnN). In the presence of 0.05 mm ATP, dinucleotides (at 0.01 mm) activated the enzyme velocity in the following decreasing order: Gp4G, 100; Gp3G, 82; Ap6A, 61; Gp2G, 52; Ap4A, 51; Ap2A, 41; Gp5G, 36; Ap5A, 27; Ap3A, 20, where 100 represents a 10-fold activation in relation to a control without effector. The velocity of the enzyme towards its substrate ATP displayed sigmoidal kinetics with a Hill coefficient (nH) of 1.6 and a Km(S0.5) value of 0.308 ± 0.120 mm. Dinucleoside polyphosphates did not affect the maximum velocity (Vmax) of the reaction, but did alter its nH and Km(S0.5) values. In the presence of 0.01 mm Gp4G or Ap4A the nH and Km(S0.5) values were (1.0 and 0.063 ± 0.012 mm) and (0.8 and 0.170 ± 0.025 mm), respectively. With these kinetic properties, a dinucleoside polyphosphate concentration as low as 1 µm may have a noticeable activating effect on the synthesis of poly(A) by the enzyme. These findings together with previous publications from this laboratory point to a potential relationship between dinucleoside polyphosphates and enzymes catalyzing the synthesis and/or modification of DNA or RNA. [source] Anti-oxidant activity of added tea catechins on lipid oxidation of raw minced red meat, poultry and fish muscleINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 6 2001Shuze Tang The comparative anti-oxidative effects of added tea catechins (TC) and ,-tocopherol to raw minced red meat (beef and pork), poultry (chicken, duck and ostrich) and fish (whiting and mackerel) muscle on susceptibility to lipid oxidation were investigated during 10 days of refrigerated (4 °C) display. Fresh meats, poultry and fish, purchased from a local market, were trimmed to remove bones, skin and surface fat and minced through a 4 mm plate. The minced muscle of each species was treated with either the addition of 300 mg TC kg,1 minced muscle (TC300) or 300 mg ,-tocopherol kg,1 minced muscle (VE300). Minced muscle without any additives served as control (C). Oxidative stability (TBARS) was measured at 3-day intervals. Total lipids, fatty acid composition, total iron and haem iron from minced muscle for each species were also analysed. The susceptibility of untreated minced muscle to lipid oxidation was in the decreasing order: mackerel > beef > duck > ostrich > pork , chicken > whiting. This may be because of the different content of total fat, iron and fatty acid composition between species. The TC300 significantly (P < 0.05) reduced lipid oxidation compared with controls for all seven species as shown by lower TBARS values. The anti-oxidant potential of TC was two to fourfold greater than that of ,-tocopherol at the same concentration and this potential was species dependent. The VE300 showed limited capacity in inhibiting lipid oxidation for pork, chicken, duck and whiting. The results obtained show that TCs are powerful natural antioxidants when used in minced muscle food. [source] Effects of variety, cropping year, location and fertilizer application on nutritive value of durum wheat strawJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 2 2008A. Tolera Summary This study was carried out to assess the effects of variety, year, location and level of fertilizer application on chemical composition and in sacco dry matter (DM) degradability of durum wheat straw as well as to understand the relationship between straw quality and agronomic traits of the crop and to assess the possibilities of selecting wheat varieties that combine high grain yield with desirable straw quality. Two local (Arendeto and Tikur sinde) and two improved (Boohai and Gerardo) varieties of durum wheat (Triticum turgidum Desf.) were used in the experiment. The four varieties were grown at two locations (Akaki and Ejere) in the years 2001/2002 and 2002/2003 in 5 × 5 m plots in three replications. Diammonium phosphate and urea fertilizers were applied at four levels (0/0, 32/23, 41/23 and 64/46 kg/ha of nitrogen/phosphorus). Straw quality was assessed based on chemical composition and in sacco DM degradability. Correlation of straw quality with grain and straw yield and with other agronomic characteristics of the crop was determined. The potential utility index (a measure that integrates grain and digestible straw yield) was used for ranking of the varieties. The local varieties had higher crude protein (CP) and lower neutral detergent fibre contents and higher digestibility than the improved varieties. The cropping year and location had significant effect on CP content and degradability of the straw, which could be due to climatic variation. However, the fertilizer level did not have any significant effect on straw quality except that the CP content of the straw tended to increase with increasing level of fertilizer application. Based on the potential utility index the varieties ranked, in a decreasing order, as Tikur sinde > Arendeto > Gerardo > Boohai and the ranking was consistent across years and locations. Except the CP content, straw quality was not negatively correlated with grain and straw yield. This indicates that there is a possibility of selecting varieties of wheat that combine high grain and straw yield with desirable straw quality. [source] Photografting of acrylic acid and methacrylic acid onto polyolefines initiated by formaldehyde in aqueous solutionsJOURNAL OF APPLIED POLYMER SCIENCE, Issue 4 2009Jianmei Han Abstract Formaldehyde aqueous solution can act as an effective photoinitiating system for water-borne photografting. The photografting of acrylic acid (AA) and methacrylic acid (MAA) onto high-density polyethylene (HDPE), low-density polyethylene (LDPE) and polypropylene (PP) initiated by formaldehyde aqueous solutions has been reported. The effects of formaldehyde content and monomer concentration on grafting varied with the polymeric substrates and monomers used. For the grafting of AA onto HDPE, the extent of grafting increased with increasing formaldehyde content in the solution, monomer concentration had a little effect on grafting. Whereas for the grafting of MAA onto HDPE, the grafting performed in 8% formaldehyde aqueous solution lead to the highest extent of grafting, the extent of grafting increased with monomer concentration till 2.5 mol/L. MAA was easier to be grafted onto the polyolefins than AA. The easiness of grafting occurring on the polyolefins was in a decreasing order of LDPE > HDPE > PP. Qualitative and semi-quantitative Fourier transform infrared (FTIR) characterizations of the grafted samples were performed. For both grafted LDPE and PP samples, at the same irradiation time, the carbonyl index of the samples grafted with MAA was higher than that grafted with AA. The FTIR results are in accord with the results obtained by gravimetric method. The water absorbency of the grafted samples increased almost linearly with the extent of grafting. The PE films grafted with AA adsorbed more water than those grafted with MAA. This study had broadened the water-borne initiating system for photografting. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 [source] Synthesis of gradient copolymers with complexing groups by RAFT polymerization and their solubility in supercritical CO2JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 20 2009Tiphaine Ribaut Abstract We report the synthesis of new gradient fluorinated copolymers with complexing groups and soluble in supercritical carbon dioxide (scCO2). Poly(1,1,2,2-tetrahydroperfluorodecyl acrylate- co -acetoacetoxyethyl methacrylate) (poly(FDA- co -AAEM)) and poly(1,1,2,2-tetrahydroperfluorodecyl acrylate- co -vinylbenzylphosphonic acid diethylester) (poly(FDA- co -VBPDE)) gradient copolymers were synthesized by reversible addition fragmentation chain transfer polymerization in ,,,,,-trifluorotoluene. Poly(1,1,2,2-tetrahydroperfluorodecyl acrylate- co -vinylbenzylphosphonic diacid) (poly(FDA- co -VBPDA)) gradient copolymer was efficiently obtained by cleavage of the phosphonic ester groups of poly(FDA- co -VBPDE). The cloud points of these gradient copolymers in dense CO2 were measured in a variable volume view cell at temperatures between 25 and 65 °C. The gradient copolymers show very good solubility in compressed CO2 with the decreasing order: poly(FDA- co -AAEM) , poly(FDA- co -VBPDE) > poly(FDA- co -VBPDA). Following a green chemistry strategy, poly(FDA- co -AAEM) gradient copolymer was successfully synthesized in scCO2 with a good control over number-average molecular weight and composition. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5448,5460, 2009 [source] Expression Pattern, Ethanol-Metabolizing Activities, and Cellular Localization of Alcohol and Aldehyde Dehydrogenases in Human Pancreas: Implications for Pathogenesis of Alcohol-Induced Pancreatic InjuryALCOHOLISM, Issue 6 2009Chien-Ping Chiang Background:, Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) are major enzymes responsible for metabolism of ethanol. Genetic polymorphisms of ADH1B, ADH1C, and ALDH2 occur among racial populations. The metabolic effect and metabolites contribute to pathogenesis of pancreatic injury. The goal of this study was to determine the functional expressions and cellular localization of ADH and ALDH families in human pancreas. Methods:, Fifty five surgical specimens of normal pancreas as well as 15 samples each for chronic pancreatitis and pancreatic cancer from archival formalin-fixed paraffin-embedded tissue specimens were investigated. Class-specific antibodies were prepared by affinity chromatographies from rabbit antisera raised against recombinant human ADH1C1, ADH4, ADH5, ADH7, ALDH1A1, ALDH2, and ALDH3A1. The isozyme expression patterns of ADH/ALDH were identified by isoelectric focusing, and the activities were assayed spectrophotometrically. The protein contents of ADH/ALDH isozymes were determined by immunoblotting, and the cellular localizations were detected by immunohistochemistry and histochemistry. Results:, At 33 mM ethanol, pH 7.5, the activities were significantly different between allelic phenotypes of ADH1B. The activity of ALDH2-inactive phenotypes was slightly lower than ALDH2-active phenotypes at 200 ,M acetaldehyde. The protein contents were in the following decreasing order: ALDH1A1, ALDH2, ADH1, and ADH5. ADH1B was detected in the acinar cells and ADH1C in the ductular, islet, and stellate cells. The expression of ADH1C appeared to be increased in the activated pancreatic stellate cells in chronic pancreatitis and pancreatic cancer. Conclusions:, Alcohol dehydrogenase and ALDH family members are differentially expressed in the various cell types of pancreas. ADH1C may play an important role in modulation of activation of pancreatic stellate cells. [source] Effects of dietary squid viscera meal on growth and cadmium accumulation in tissues of Japanese seabass, Lateolabrax japonicus (Cuvier 1828)AQUACULTURE RESEARCH, Issue 11 2006Kangsen Mai Abstract Cadmium (Cd) is a toxic environmental pollutant with a long biological half-life and can produce both hepatic and renal injuries in mammals and fish. Squid viscera meal (SVM), an effective attractant for aquatic animals, is widely used as an ingredient in aquafeeds. However, SVM is rich in Cd and its complexes. A study was conducted to evaluate the effects of dietary SVM on the growth and Cd deposition in tissues of Japanese seabass, Lateolabrax japonicus. Three practical diets were formulated to contain 0, 50 and 100 g SVM kg,1 diet, respectively, containing 0.21, 7.26 and 12.08 mg Cd kg,1 diet. Each diet was randomly assigned to triplicate groups of 80 Japanese seabass (mean initial weight, 10.89±0.21 g) in floating sea cages (1.5 × 1.5 × 2.0 m). Fish were fed twice daily (06:30 and 16:30 hours) to satiation for 8 weeks. The results showed that there were no significant differences in fish survival among three dietary treatments, but significant higher specific growth rates (SGR) were observed in the fish fed diets with 50 or 100 g SVM kg,1 diet than that from the control group (P<0.05). The Cd concentrations in the kidney, liver and gill were found in a decreasing order at each treatment, and positively correlated with dietary Cd levels. Fish fed diets with 50 and 100 g SVM kg,1 diet had significantly higher Cd accumulations in the kidney (3.25, 5.85 mg kg,1), liver (0.76, 1.26 mg kg,1) and gill (0.42, 0.58 mg kg,1) compared with the control group (0.82, 0.34 and 0.32 mg kg,1 respectively) (P<0.05). The Cd concentration in fish muscle; however, was undetectable in any treatment. Therefore, based on these results, accumulation of Cd in edible tissue (muscle) of farmed Japanese seabass is not a food safety issue. However, long-term feeding of diets with SVM may result in accumulation of Cd in the kidneys, liver and gills of fish. [source] Determination of trimebutine maleate in rat plasma and tissues by using capillary zone electrophoresisBIOMEDICAL CHROMATOGRAPHY, Issue 4 2001Famei Li A simple and rapid capillary zone electrophoresis method was developed for the determination of trimebutine maleate in rat plasma and tissues. Rat plasma and tissue homogenates were mixed with acetonitrile containing internal standard, ephedrine hydrochloride, and then centrifuged. The supernatant was dried under a stream of nitrogen, and the residue was reconstituted in methanol,water (1:1). The electrophoresis was performed in uncoated capillary with 30,mmol/L phosphate buffer of pH 6.0 as the separation electrolyte. The applied voltage was 10,kV and the UV detection was set at 214,nm. The peak height ratio vs concentration in plasma or homogenates was linear over the range of 5,500,ng/mL and the limit of quantitation was 5,ng/mL. The intra- and inter-day precision was RSD,<,14% and <15%. The accuracy was relative error (RE) within,±,14%. This method was applied to studying the pharmacokinetics and tissue distribution after a single dose of trimebutine maleate was administrated to the rats. The Tmax, AUC, Cmax and t1/2 were 30,min, 7.8,×,102 (ng/mL),min, 39,ng/mL and 1.7,×,102,min. The drug distribution was found in a decreasing order of liver, kidney, spleen, lung and heart. Copyright © 2001 John Wiley & Sons, Ltd. [source] | ||||||||||||||||