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91.
We examined gazelle peripheral blood leucocytes using the α-Naphthyl acetate esterase (ANAE) staining technique (pH 5.8). Our purpose was to determine the percentage of ANAE positive lymphocytes. The proportion of ANAE positive T-lymphocytes was 72%. T-lymphocytes showed an ANAE positive reaction, but eosinophilic granulocytes and monocytes also showed a positive reaction. By contrast, no reaction was detected in B-lymphocytes, neutrophil granulocytes or platelets. The reaction observed in T-lymphocytes was a red-brown coloration, usually 1–2 granules, but enough granules to fill the cytoplasm were detected rarely. As a result of ANAE enzyme staining, we concluded that the staining technique can be used as a cytochemical marker for gazelle T-lymphocytes. 相似文献
92.
《Biotechnic & histochemistry》2013,88(4):265-272
The purpose of our study was to determine the percentages of α-naphthyl acetate esterase (ANAE)- and acid phosphatase (ACP)-positive peripheral blood lymphocytes (PBL), the presence of the ANAE and ACP enzymes in leukocytes, and the proportion of PBL in greyhounds. Peripheral blood samples were collected from the cephalic antebrachial vein of 14 (7 animals of each sex) healthy 1-2-year-old greyhounds. Mean percentages of ANAE-positive PBL were found to be 73.29 ± 0.95% in female and 74.29 ± 2.21% in male dogs. The difference between mean values of the genders was not statistically significant. The ACP values were 36.00 ± 2.94% for females and 33.57 ± 2.15% for males. No significant differences were found with regard to gender. For both enzymes, although monocytes and eosinophilic granulocytes displayed a positive reaction, neutrophils gave negative reactions. The proportion of PBL was 36.29 ± 5.31% and 33.00 ± 2.38 % in female and male dogs, respectively. The differences were not significant. 相似文献
93.
《Biocatalysis and Biotransformation》2013,31(4):155-160
AbstractPinolenic acid (PLA) enrichment as an ethyl ester from pine nut oil was successfully accomplished in a batch reactor by lipase-catalyzed ethanolysis using Novozym 435 lipase from Candida antarctica as a biocatalyst. PLA is predominantly an sn-3 substituent of the pine nut oil triacylglycerol (TAG), where it accounts for about 39 mol% of the fatty acids esterified at that position. In the presence of ethanol, Novozym 435 exhibited sn-3 regiospecificity with respect to the TAG of pine nut oil. The effect of the molar ratio of reactants on PLA enrichment by ethanolysis was investigated. The molar ratios of pine nut oil to ethanol were varied from 1:20 to 1:100. A fatty acid ethyl ester (FAEE) fraction with higher PLA content was obtained in the early stage of the reaction, although the yield of PLA was small. However, the PLA content of the FAEEs decreased with increasing reaction time, while the yield of PLA increased. The molar ratio of pine nut oil to ethanol that produced the optimum content and yield of PLA in FAEEs was 1:80. 相似文献
94.
Consuelo Sandoval José M. Méndez Rubén Sánchez-Obregón Carmen B. Alpízar 《Biocatalysis and Biotransformation》2013,31(1):36-44
Cultured plant cells from Taxus brevifolia Nutt and Taxus globosa Schltdl were investigated as biocatalysts using exogenous substrates. Production of highly specific metabolites by these species prompted us to analyse their synthetic potential. Whole cells suspensions have the capacity to chemoselectively reduce ethyl acetoacetate to ethyl 3-hydroxybutyrate chemo- and stereoselectively reduce rac-2-benzoylcyclohexanone to (1R, 2S)- and (1S, 2S)-2-hydroxycyclohexylphenylmethanones, and to cyclize N-phthaloyl-L-glutamine to thalidomide. 相似文献
95.
Abdala Hiam David Sebastien Bekesi George Fellous Arlette Jorge Kalil Patrice Le Pape 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):305-312
A new family of antimicrotubule drugs named (3-haloacetamidobenzoyl) ureas and ethyl 3-haloacetamidobenzoates were found to be cytotoxic to the Leishmania parasite protozoa. While the benzoylureas were shown to strongly inhibit in vitro mammalian brain microtubule assembly, the ethyl ester derivatives were characterized as very poor inhibitors of this process. Ethyl 3-chloroacetamidobenzoate, MF29, was found to be the most efficient drug on the promastigote stage of three Leishmania species (IC50: 0.3–1.8 μM). MF29 maintained its activity against the clinical relevant intracellular stage of L. mexicana with IC50 value of 0.33 μM. It was the only compound that exhibits a high activity on all the Leishmania species tested. This compound appeared to alter parasite microtubule organisation as demonstrated by using antibodies directed against microtubule components and more precisely the class of microtubule decorated by the MAP2-like protein. It is interesting to notice that this MAP2-like protein was identified for the first time in a Leishmania parasite 相似文献
96.
Biochemical modifications of gliadins induced by microbial transglutaminase on wheat flour 总被引:1,自引:0,他引:1
Maria F. Mazzeo Roberta BonavitaFrancesco Maurano Paolo BergamoRosa A. Siciliano Mauro Rossi 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Celiac disease (CD) is an immune-mediated disorder caused by the ingestion of wheat gluten. A lifelong, gluten-free diet is required to normalize the intestinal mucosa. We previously found that transamidation by microbial transglutaminase (mTGase) suppressed the gliadin-specific immune response in intestinal T-cell lines from CD patients and in models of gluten sensitivity.Methods
SDS-PAGE, Western blot, ELISA, tissue transglutaminase (tTGase) assay and nano-HPLC–ESI-MS/MS experiments were used to analyze prolamins isolated from treated wheat flour.Results
Gliadin and glutenin yields decreased to 7.6 ± 0.5% and 7.5 ± 0.3%, respectively, after a two-step transamidation reaction that produced a water-soluble protein fraction (spf). SDS-PAGE, Western blot and ELISA analyses confirmed the loss of immune cross-reactivity with anti-native gliadin antibodies in residual transamidated gliadins (K-gliadins) and spf as well as the occurrence of neo-epitopes. Nano-HPLC–ESI-MS/MS experiments identified some native and transamidated forms of celiacogenic peptides including p31–49 and confirmed that mTGase had similar stereo-specificity of tTGase. Those peptides resulted to be 100% and 57% modified in spf and K-gliadins, respectively. In particular, following transamidation p31–49 lost its ability to increase tTGase activity in Caco-2 cells. Finally, bread manufactured with transamidated flour had only minor changes in baking characteristics.Conclusions
The two-step transamidation reaction modified the analyzed gliadin peptides, which are known to trigger CD, without influencing main technological properties.General significance
Our data shed further light on a detoxification strategy alternative to the gluten free diet and may have important implications for the management of CD patients. 相似文献97.
Exposing Pseudomonas aeruginosa biofilm grown on the inner surface of Teflon and silicone tubes to UVC light (265 nm) from light emitting diodes (LED) has previously been shown to substantially reduce biofilm growth. Smaller UVC fluencies were required to disinfect Teflon tubes compared to silicone tubes. Light propagation enhancement in tubes can be obtained if the refractive index of the intra-luminal saline solution is higher than that of the polymer. This condition is achieved by using Teflon tubes with a low refractive index (1.34) instead of the polymers with a high refractive index (1.40–1.50) normally used for tubing in catheter production. Determining whether or not UVC light exposure can disinfect and maintain the intra-luminal number of colony forming units (CFUs) at an exceedingly low level and thus avoid the growth and establishment of biofilm is of interest. The use of UVC diodes is demonstrated to be a preventative disinfection treatment on tubes made of Teflon, which enhances the UVC light propagation, and on tubes made of a softer material, ethylene vinyl acetate (EVA), which is suitable for catheters but much less suitable for UVC light propagation. Simulating an aseptic breach (~103–104 CFU ml?1), the UVC disinfection set-up was demonstrated using tubes contaminated with planktonic P. aeruginosa. After the tubes (10–20 cm) were inoculated with the bacterial solution for 3 h, they were emptied and filled with saline solutions (0.9–20%). Next UVC fluencies (0–21 mJ cm?2) were applied to the tubes 3 h after inoculation. Colony counts were carried out on liquid samples drawn from the tubes the first day after UVC treatment and liquid and surface samples were collected and analyzed 3–4 days later. A fluence of approximately 1.0 mJ cm?2 was noted as being sufficient for no growth for a period of 3–4 days for the Teflon tubes. Determining the fluence threshold for the EVA tubes was not possible. Almost all of the UVC-treated EVA tubes were disinfected simply by filling the tubes with a saline solution. Direct UVC treatment of the contaminated EVA tubes revealed, however, that a fluence of 21 mJ cm?2 killed the bacteria present in the tubes and kept them disinfected for a period of 3–4 days. 相似文献
98.
Several chiral ligands containing (R,R)‐diaminocyclohexane moieties and pyrrole, furan, or benzene have been synthesized. These ligands were tested in enantioselective zinc‐catalyzed hydrosilylation reactions; excellent enantioselectivities were obtained when the ligands containing (R,R)‐diaminocyclohexane moieties and furan rings were used. For comparison, zinc chloride combined with different potassium carboxylate salts and ligands were also tested for catalytic hydrosilylation reactions. Chirality 25:275–280, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
99.
Electrospun cellulose acetate nanofibers: The present status and gamut of biotechnological applications 总被引:1,自引:0,他引:1
Cellulose acetate (CA) has been a material of choice for spectrum of utilities across different domains ranging from high absorbing diapers to membrane filters. Electrospinning has conferred a whole new perspective to polymeric materials including CA in the context of multifarious applications across myriad of niches. In the present review, we try to bring out the recent trend (focused over last five years' progress) of research on electrospun CA fibers of nanoscale regime in the context of developmental strategies of their blends and nanocomposites for advanced applications. In the realm of biotechnology, electrospun CA fibers have found applications in biomolecule immobilization, tissue engineering, bio-sensing, nutraceutical delivery, bioseparation, crop protection, bioremediation and in the development of anti-counterfeiting and pH sensitive material, photocatalytic self-cleaning textile, temperature-adaptable fabric, and antimicrobial mats, amongst others. The present review discusses these diverse applications of electrospun CA nanofibers. 相似文献
100.