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Karol Mičieta 《Folia Geobotanica》1983,18(3):329-331
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A new sewage treatment system was studied, which consisted of an anaerobic baffled filter reactor and the following aerobic post-treatment. One of the two studied systems (AN-I) was inoculated with psychrophilic digested sludge, the second one (AN-II) was operated without inoculation. The HRT in anaerobic and aerobic parts of the reactors were about 15 and 4 h, respectively. The temperature in both reactors varied during the year from 4.5 to 23 degrees C. All monitored parameters were removed with relatively high efficiencies (COD = 78.6-83.0%, BOD5 = 92.5-94.0% and SS = 80.9-92.7%). An intensive nitrification process was observed during the whole year in both reactors (under average temperature of 5.9 degrees C in January 2000, also). The average removal of the NH4-N varied during the year from 46.4% to 87.3%. In both systems a partial denitrification process was observed, too. 相似文献
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Transepithelial transport and enzymatic detoxification of gluten in gluten-sensitive rhesus macaques
Background and Aims
In a previous report, we characterized a condition of gluten sensitivity in juvenile rhesus macaques that is similar in many respects to the human condition of gluten sensitivity, celiac disease. This animal model of gluten sensitivity may therefore be useful toward studying both the pathogenesis and the treatment of celiac disease. Here, we perform two pilot experiments to demonstrate the potential utility of this model for studying intestinal permeability toward an immunotoxic gluten peptide and pharmacological detoxification of gluten in vivo by an oral enzyme drug candidate.Methods
Intestinal permeability was investigated in age-matched gluten-sensitive and control macaques by using mass spectrometry to detect and quantify an orally dosed, isotope labeled 33-mer gluten peptide delivered across the intestinal epithelium to the plasma. The protective effect of a therapeutically promising oral protease, EP-B2, was evaluated in a gluten-sensitive macaque by administering a daily gluten challenge with or without EP-B2 supplementation. ELISA-based antibody assays and blinded clinical evaluations of this macaque and of an age-matched control were conducted to assess responses to gluten.Results
Labeled 33-mer peptide was detected in the plasma of a gluten-sensitive macaque, both in remission and during active disease, but not in the plasma of healthy controls. Administration of EP-B2, but not vehicle, prevented clinical relapse in response to a dietary gluten challenge. Unexpectedly, a marked increase in anti-gliadin (IgG and IgA) and anti-transglutaminase (IgG) antibodies was observed during the EP-B2 treatment phase.Conclusions
Gluten-sensitive rhesus macaques may be an attractive resource for investigating important aspects of celiac disease, including enhanced intestinal permeability and pharmacology of oral enzyme drug candidates. Orally dosed EP-B2 exerts a protective effect against ingested gluten. Limited data suggest that enhanced permeability of short gluten peptides generated by gastrically active glutenases may trigger an elevated antibody response, but that these antibodies are not necessarily causative of clinical illness. 相似文献7.
Björkbom A Róg T Kankaanpää P Lindroos D Kaszuba K Kurita M Yamaguchi S Yamamoto T Jaikishan S Paavolainen L Päivärinne J Nyholm TK Katsumura S Vattulainen I Slotte JP 《Biochimica et biophysica acta》2011,1808(4):1179-1186
We have prepared palmitoyl sphingomyelin (PSM) analogs in which either the 2-NH was methylated to NMe, the 3-OH was methylated to OMe, or both were methylated simultaneously. The aim of the study was to determine how such modifications in the membrane interfacial region of the molecules affected interlipid interactions in bilayer membranes. Measuring DPH anisotropy in vesicle membranes prepared from the SM analogs, we observed that methylation decreased gel-phase stability and increased fluid phase disorder, when compared to PSM. Methylation of the 2-NH had the largest effect on gel-phase instability (T(m) was lowered by ~7°C). Atomistic molecular dynamics simulations showed that fluid phase bilayers with methylated SM analogs were more expanded but thinner compared to PSM bilayers. It was further revealed that 3-OH methylation dramatically attenuated hydrogen bonding also via the amide nitrogen, whereas 2-NH methylation did not similarly affect hydrogen bonding via the 3-OH. The interactions of sterols with the methylated SM analogs were markedly affected. 3-OH methylation almost completely eliminated the capacity of the SM analog to form sterol-enriched ordered domains, whereas the 2-NH methylated SM analog formed sterol-enriched domains but these were less thermostable (and thus less ordered) than the domains formed by PSM. Cholestatrienol affinity to bilayers containing methylated SM analogs was also markedly reduced as compared to its affinity for bilayers containing PSM. Molecular dynamics simulations revealed further that cholesterol's bilayer location was deeper in PSM bilayers as compared to the location in bilayers made from methylated SM analogs. This study shows that the interfacial properties of SMs are very important for interlipid interactions and the formation of laterally ordered domains in complex bilayers. 相似文献
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The dry climate that prevailed during the Triassic period in the eastern part of the Central European Basin was interrupted by several humid episodes of varying durations. One of them was the Carnian Pluvial Episode (CPE), which took place in the late Julian (early Carnian age) and is confined to Camerosporites secatus and Aulisporites astigmosus palynological zones. CPE is marked by a significant change in the qualitative and quantitative composition of spore-pollen assemblages from mostly xerophytic species preserved in the upper part of the Grabfeld Formation (“Lower Gipskeuper”) to hygrophytic forms, which dominate in the Stuttgart Formation (“Schilfsandstein”). Changes in climate towards more humid conditions have been documented palynologically and sedimentologically, and analyzed utilizing quantitative spore-pollen analysis and Principal Component Analysis (PCA) of miospores occurring in core material from Poland. In all the studied boreholes, a shift from dry to wet climate is observed at the boundary between the Grabfeld Formation and the Stuttgart Formation, which matches the data from other European regions. 相似文献
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This review focuses on four new product categories of food supplements: pre-workout, fat burner/thermogenic, brain/cognitive booster, and hormone/testosterone booster. Many food supplements have been shown to be contaminated with unauthorized substances. In some cases, the ingredients in the new categories of dietary supplements were medicinal products or new synthetic compounds added without performing clinical trials. Some of the new ingredients in dietary supplements are plant materials that are registered in the pharmacopoeia as herbal medicines. In other cases, dietary supplements may contain plant materials that have no history of human use and are often used as materials to ‘camouflage’ stimulants. In the European Union, new ingredients of dietary supplements, according to European Food Safety Authority or unauthorized novel food. Furthermore, selected ingredients in dietary supplements may be prohibited in sports and are recognized as doping agents by World Anti-Doping Agency. 相似文献
10.
Leen Depauw Michael P. Perring Dries Landuyt Sybryn L. Maes Haben Blondeel Emiel De Lombaerde Guntis Brūmelis Jörg Brunet Déborah Closset-Kopp Guillaume Decocq Jan Den Ouden Werner Härdtle Radim Hédl Thilo Heinken Steffi Heinrichs Bogdan Jaroszewicz Martin Kopecký Ilze Liepiņa Martin Macek František Máliš Wolfgang Schmidt Simon M. Smart Karol Ujházy Monika Wulf Kris Verheyen 《应用植被学》2021,24(1):e12532