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91.
Josef Marksteiner Imrich Blasko Georg Kemmler Therese Koal Christian Humpel 《Metabolomics : Official journal of the Metabolomic Society》2018,14(1):1
Introduction
There is still a clear need for a widely available, inexpensive and reliable method to diagnose Alzheimer’s disease (AD) and monitor disease progression. Liquid chromatography–mass spectrometry (LC-MS) is a powerful analytic technique with a very high sensitivity and specificity.Objectives
The aim of the present study is to measure concentrations of 20 bile acids using the novel Kit from Biocrates Life Sciences based on LC-MS technique.Methods
Twenty bile acid metabolites were quantitatively measured in plasma of 30 cognitively healthy subjects, 20 patients with mild cognitive impairment (MCI) and 30 patients suffering from AD.Results
Levels of lithocholic acid were significantly enhanced in plasma of AD patients (50?±?6 nM, p?=?0.004) compared to healthy controls (32?±?3 nM). Lithocholic acid plasma levels of MCI patients (41?±?4 nM) were not significantly different from healthy subjects or AD patients. Levels of glycochenodeoxycholic acid, glycodeoxycholic acid and glycolithocholic acid were significantly higher in AD patients compared to MCI patients (p?<?0.05). All other cholic acid metabolites were not significantly different between healthy subjects, MCI patients and AD patients. ROC analysis shows an overall accuracy of about 66%. Discriminant analysis was used to classify patients and we found that 15/23 were correctly diagnosed. We further showed that LCA levels increased by about 3.2 fold when healthy subjects converted to AD patients within a 8–9 year follow up period. Pathway analysis linked these changes to a putative toxic cholesterol pathway.Conclusion
In conclusion, 4 bile acids may be useful to diagnose AD in plasma samples despite limitations in diagnostic accuracy.92.
Therese Klemetsrud Anna-Lena Kjøniksen Marianne Hiorth Jette Jacobsen Gro Smistad 《Journal of liposome research》2018,28(1):62-73
In this study we investigated the in vitro toxicity, impact on cell permeability and mucoadhesive potential of polymer-coated liposomes intended for use in the oral cavity. A TR146 cell line was used as a model. The overall aim was to end up with a selection of safe polymer coated liposomes with promising mucoadhesive properties for drug delivery to the oral cavity. The following polymers were tested: chitosan, low-methoxylated pectin (LM-pectin), high-methoxylated pectin (HM-pectin), amidated pectin (AM-pectin), Eudragit, poly(N-isopropylacrylamide-co-methacrylic acid) (p(NIPAAM-co-MAA)), hydrophobically modified hydroxyethyl cellulose (HM-HEC), and hydrophobically modified ethyl hydroxyethyl cellulose (HM-EHEC). With chitosan as an exception, all the systems exhibited no significant effect on cell viability and permeability at the considered concentrations. Additionally, all the formulations showed to a varying degree an interaction with mucin (BSM type I-S); the positively charged formulations exhibited the strongest interaction, while the negatively and neutrally charged formulations displayed a moderate or low interaction. The ability to interact with mucin makes all the liposomal formulations promising for oromucosal administration. Although the chitosan-coated liposomes affected the cell viability, this formulation also influenced the cell permeability, which makes it an interesting candidate for systemic drug delivery from the oral cavity. 相似文献
93.
94.
Carboxyarabinitol 1-phosphate (CA1P) phosphatase activity occurredin leaves of 10 species examined, with the highest activityin leaves of Phaseolus vulgaris. Enzyme was purified from P.vulgaris 1,580-fold to a final specific activity of 6.1 µmolmin1 (mg protein)1. Structural characteristicsof positive effectors and substrate analogs for the CA1P phosphatasereaction were examined. Positive effectors were compounds thatcontained one phosphate group in close proximity to a secondphosphate or a carboxyl group (e.g. 2-phosphoglycolate, pyrophosphate,3-phosphoglycerate, and carboxyethylphosphonic acid). Many ofthe activators are structurally quite similar to CA1P, but werenot used as substrates. In addition to the natural substrateCA1P, carboxypentitol and carboxyhexitol bisphosphates wereshown to be good substrates (e.g. carboxyarabinitol bisphosphateand carboxymannitol bis-phosphate). A substrate arabinitol configuration(R) was preferred at C-2, and reactivity was lost when a hydroxymethylgroup was substituted for the carboxyl group. Despite structuralsimilarities to positive effectors, none of the tested reactionsubstrates could activate the enzyme. (Received November 11, 1996; Accepted February 3, 1997) 相似文献
95.
O'Flaherty Vincent Mahony Therese Moran Anthony P. Lens Piet 《Reviews in Environmental Science and Biotechnology》2003,2(2-4):83-83
Reviews in Environmental Science and Bio/Technology - 相似文献
96.
Dag Anders Brede Therese Faye Melanie Patricia Stierli Gottfried Dasen Anita Theiler Ingolf F. Nes Leo Meile Helge Holo 《Applied microbiology》2005,71(12):8077-8084
Heterologous bacteriocin production in Propionibacterium freudenreichii is described. We developed an efficient system for DNA shuttling between Escherichia coli and P. freudenreichii using vector pAMT1. It is based on the P. freudenreichii rolling-circle replicating plasmid pLME108 and carries the cml(A)/cmx(A) chloramphenicol resistance marker. Introduction of the propionicin T1 structural gene (pctA) into pAMT1 under the control of the constitutive promoter (P4) yielded bacteriocin in amounts equal to those of the wild-type producer Propionibacterium thoenii 419. The P. freudenreichii clone showed propionicin T1 activity in coculture, killing 90% of sensitive bacteria within 48 h. The pamA gene from P. thoenii 419 encoding the protease-activated antimicrobial peptide (PAMP) was cloned and expressed in P. freudenreichii, resulting in secretion of the pro-PAMP protein. Like in the wild type, PAMP activation was dependent on externally added protease. Secretion of the antimicrobial peptide was obtained from a clone in which the pamA signal peptide and PAMP were fused in frame. The promoter region of pamA was identified by fusion of putative promoter fragments to the coding sequence of the pctA gene. The P4 and Ppamp promoters directed constitutive gene expression, and activity of both promoters was enhanced by elements upstream of the promoter core region. 相似文献
97.
98.
Replication of Deoxyribonucleic Acid During the Division Cycle of Salmonella typhimurium 总被引:5,自引:5,他引:0
The rate of thymidine incorporation into cells of Salmonella typhimurium growing in different media has been measured. In glucose-minimal medium, deoxyribonucleic acid (DNA) replication occurs during the first two-thirds of the division cycle; the final one-third of the division cycle was devoid of DNA replication. The measured doubling time of S. typhimurium in this medium is approximately 48 min, indicating that C (the time for a round of replication) and D (the time between termination and cell division) are approximately 32 and 16 min, respectively. At slower growth rates the pattern of replication is the same as glucose minimal medium. At faster growth rates the "gap" in DNA synthesis disappears. At rapid growth rates evidence for multiple forks is obtained. 相似文献
99.
100.