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121.
Janssen EM van Oosterhout AJ van Rensen AJ van Eden W Nijkamp FP Wauben MH 《Journal of immunology (Baltimore, Md. : 1950)》2000,164(2):580-588
Allergen-specific CD4+ Th2 cells play an important role in the immunological processes of allergic asthma. Previously we have shown that, by using the immunodominant epitope OVA323-339, peptide immunotherapy in a murine model of OVA induced allergic asthma, stimulated OVA-specific Th2 cells, and deteriorated airway hyperresponsiveness and eosinophilia. In the present study, we defined four modulatory peptide analogues of OVA323-339 with comparable MHC class II binding affinity. These peptide analogues were used for immunotherapy by s.c. injection in OVA-sensitized mice before OVA challenge. Compared with vehicle-treated mice, treatment with the Th2-skewing wild-type peptide and a Th2-skewing partial agonistic peptide (335N-A) dramatically increased airway eosinophilia upon OVA challenge. In contrast, treatment with a Th1-skewing peptide analogue (336E-A) resulted in a significant decrease in airway eosinophilia and OVA-specific IL-4 and IL-5 production. Our data show for the first time that a Th1-skewing peptide analogue of a dominant allergen epitope can modulate allergen-specific Th2 effector cells in an allergic response in vivo. Furthermore, these data suggest that the use of Th1-skewing peptides instead of wild-type peptide may improve peptide immunotherapy and may contribute to the development of a successful and safe immunotherapy for allergic patients. 相似文献
122.
Okano R Ohki A Ohki S Kohno H van Rensen JJ Böger P Wakabayashi K 《Zeitschrift für Naturforschung. C, Journal of biosciences》2002,57(11-12):1009-1015
The effect of 2-benzylamino-1,3,5-triazines on photosynthetic electron transport (PET) was measured with thylakoids isolated from atrazine-resistant, wild-type Chenopodium album, and spinach to find novel 1,3,5-triazine herbicides bearing a strong PET inhibition. The PET inhibition assay with Chenopodium (wild-type and resistant), yielded a resistance ratio (R/W = I50 (resistant)/I50 (wild-type)) of 324 for atrazine while for benzylamino-1,3,5-triazine derivatives of diamino-1,3,5-triazines a R/W of 11 to 160 was found. The compounds having a benzylamino group at one of the amino groups in the diamino-1,3,5-triazines have a resistant ratio down to one half to 1/30 of the atrazine value. The average resistance ratio of 21 benzylamino derivatives of monoamino-1,3,5-triazines was found to be about 4.0. The inhibition of 21 benzylamino-1,3,5-triazines assayed with atrazine-resistant Chenopodium thylakoids, indicated by pI50 (R)-values, correlated well with the PET inhibition pI50 (W) of wild-type thylakoids from Chenopodium. 相似文献
123.
Anne Sietske de Boer Fergus Priest Børge Diderichsen 《Applied microbiology and biotechnology》1994,40(5):595-598
We document here that in those rare cases where disease has been related to Bacillus licheniformis, infection was associated with bypassing the normal biological protective barriers or severely debililated patients. No case suggests any invasive properties of this bacterium. B. licheniformis can therefore be considered non-pathogenic to humans in general. Food-borne illness caused by possible B. licheniformis toxins have been reported, but only in a very few cases and only in connection with consumption of inappropriately prepared food. Considerable experience concerning the industrial use of recombinant B. licheniformis strains has now accumulated and authorities in the United States, Europe and Japan have approved production with and products from recombinant B. licheniformis strains. We conclude that B. licheniformis is a safe host for the production of harmless, industrial products.
Correspondence to: B. Diderichsen 相似文献
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125.
绿色木霉代谢产物的植物毒性研究 总被引:5,自引:0,他引:5
通过人工固体培养和液体发酵研究发现绿色木霉的代谢产物对植物的幼苗生长有抑制作用,其代谢产物大量分泌到它所生长的环境中,在不同的营养基质中其代谢产物的抑制作用有差异. 相似文献
126.
Ruifang Li-Gao Renée de Mutsert Patrick C. N. Rensen Jan Bert van Klinken Cornelia Prehn Jerzy Adamski Astrid van Hylckama Vlieg Martin den Heijer Saskia le Cessie Frits R. Rosendaal Ko Willems van Dijk Dennis O. Mook-Kanamori 《Metabolomics : Official journal of the Metabolomic Society》2018,14(1):13
Introduction
Fasting metabolite profiles have been shown to distinguish type 2 diabetes (T2D) patients from normal glucose tolerance (NGT) individuals.Objectives
We investigated whether, besides fasting metabolite profiles, postprandial metabolite profiles associated with T2D can stratify individuals with impaired fasting glucose (IFG) by their similarities to T2D.Methods
Three groups of individuals (age 45–65 years) without any history of IFG or T2D were selected from the Netherlands Epidemiology of Obesity study and stratified by baseline fasting glucose concentrations (NGT (n?=?176), IFG (n?=?186), T2D (n?=?171)). 163 metabolites were measured under fasting and postprandial states (150 min after a meal challenge). Metabolite profiles specific for a high risk of T2D were identified by LASSO regression for fasting and postprandial states. The selected profiles were utilised to stratify IFG group into high (T2D probability?≥?0.7) and low (T2D probability?≤?0.5) risk subgroups. The stratification performances were compared with clinically relevant metabolic traits.Results
Two metabolite profiles specific for T2D (nfasting = 12 metabolites, npostprandial = 4 metabolites) were identified, with all four postprandial metabolites also being identified in the fasting state. Stratified by the postprandial profile, the high-risk subgroup of IFG individuals (n?=?72) showed similar glucose concentrations to the low-risk subgroup (n?=?57), yet a higher BMI (difference: 3.3 kg/m2 (95% CI 1.7–5.0)) and postprandial insulin concentrations (21.5 mU/L (95% CI 1.8–41.2)).Conclusion
Postprandial metabolites identified T2D patients as good as fasting metabolites and exhibited enhanced signals for IFG stratification, which offers a proof of concept that metabolomics research should not focus on the fasting state alone.127.
Bicarbonate (or carbon dioxide) is required for electron transport in isolated broken pea chloroplasts. The site of action of the bicarbonate ion is between the primary electron acceptor of Photosystem 2, Q, and the plastoquinone pool. After trypsin treatment the Hill reaction with ferricyanide does not require bicarbonate. Photosystem 2 inhibiting herbicides act also at this site. Therefore, a possible interaction of bicarbonate and these herbicides in their effect on photosynthetic electron transport was studied.
The reciprocal of the Hill reaction rate in CO2 -depleted chloroplasts was plotted against the reciprocal of added bicarbonate concentration in the absence and in the presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), 2-methoxy-4,6-bis (ethylamino)-1,3,5-triazine (simeton) or 4,6-dinitro- o -cresol (DNOC). From these Lineweaver-Burk plots we concluded that DCMU and simeton inhibit both bicarbonate binding and Vmax . There is a purely competitive inhibition of bicarbonate binding by DNOC. We suggest that DNOC may exert its inhibition of electron transport by removing bicarbonate from its binding site.
In isolated thylakoid membranes of Synechococcus leopoliensis we did not find a bicarbonate effect nor inhibition by DNOC after Q, indicating that in the thylakoids of this blue-green alga the binding site for bicarbonate and DNOC between Q and plastoquinone is absent. 相似文献
The reciprocal of the Hill reaction rate in CO
In isolated thylakoid membranes of Synechococcus leopoliensis we did not find a bicarbonate effect nor inhibition by DNOC after Q, indicating that in the thylakoids of this blue-green alga the binding site for bicarbonate and DNOC between Q and plastoquinone is absent. 相似文献
128.
Mariëtte R. Boon Leontine E. H. Bakker Cornelia Prehn Jerzy Adamski Maarten J. Vosselman Ingrid M. Jazet Lenka M. Pereira Arias-Bouda Wouter D. Marken van Lichtenbelt Ko Willems van Dijk Patrick C. N. Rensen Dennis O. Mook-Kanamori 《Metabolomics : Official journal of the Metabolomic Society》2017,13(5):48
Introduction
Brown adipose tissue (BAT) recently emerged as a potential therapeutic target in the treatment of obesity and associated disorders due to its fat-burning capacity. The current gold standard in assessing BAT activity is [18F]FDG PET-CT scan, which has severe limitations including radiation exposure, being expensive, and being labor-intensive. Therefore, indirect markers are needed of human BAT activity and volume.Objective
We aimed to identify metabolites in serum that are associated with BAT volume and activity in men.Methods
We assessed 163 metabolites in fasted serum of a cohort of twenty-two healthy lean men (age 24.1 (21.7–26.6) years, BMI 22.1 (20.5–23.4) kg/m2) who subsequently underwent a cold-induced [18F]FDG PET-CT scan to assess BAT volume and activity. In addition, we included three replication cohorts consisting of in total thirty-seven healthy lean men that were similar with respect to age and BMI compared to the discovery cohort.Results
After correction for multiple testing, fasting concentrations of lysophosphatidylcholine-acyl (LysoPC-acyl) C16:1, LysoPC-acyl C16:0 and phosphatidylcholine-diacyl C32:1 showed strong positive correlations with BAT volume (β=?116 (85–148) mL, R2?=?0.81, p?=?4.6?×?10?7 ; β?=?79 (93–119) mL, R2?=?0.57, p?=?5.9?×?10?4 and β=?91 (40–141) mL, R2?=?0.52, p?=?1.0?×?10?3, respectively) as well as with BAT activity (β=?0.20 (0.11–0.29) g/mL, R2?=?0.59, p?=?1.9?×?10?4; β?=?0.15 (0.06–0.23) g/mL, R2?=?0.47, p?=?2.0?×?10?3 and β=?0.13 (0.01–0.25) g/mL, R2?=?0.28, p?=?0.04, respectively). When tested in three independent replication cohorts (total n?=?37), the association remained significant between LysoPC-acyl C16:0 and BAT activity in a pooled analysis (β=?0.15 (0.07–0.23) g/mL, R2?=?0.08, p?=?4.2?×?10?4).Conclusions
LysoPC-acyl C16:0 is associated with BAT activity in men. Since BAT is regarded as a promising tool in the battle against obesity and related disorders, the identification of such a noninvasive marker is highly relevant.129.
130.