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71.
Resting CD4+ T cells from human immunodeficiency virus type 1 (HIV-1)-infected individuals carry integrated HIV-1 genomes within actively transcribed host genes 下载免费PDF全文
Han Y Lassen K Monie D Sedaghat AR Shimoji S Liu X Pierson TC Margolick JB Siliciano RF Siliciano JD 《Journal of virology》2004,78(12):6122-6133
72.
Cichewicz RH Clifford LJ Lassen PR Cao X Freedman TB Nafie LA Deschamps JD Kenyon VA Flanary JR Holman TR Crews P 《Bioorganic & medicinal chemistry》2005,13(19):5600-5612
Electrospray ionization mass spectrometry-guided isolation of extracts from Didiscus aceratus led to the discovery of several new derivatives of the bioactive bisabolene-type sponge metabolite (S)-(+)-curcuphenol (1). The compounds obtained by this method included a mixture of known (2) and new (3) dihydroxylated analogs as well as a novel family of dimeric derivatives, dicurcuphenols A-E (4-8), and dicurcuphenol ether F (9). Dimers 4-9 were also subsequently obtained through a hemisynthetic method in which 1 was incubated with the enzyme laccase. Atropisomeric dimers 5 and 6 were subjected to vibrational circular dichroism analysis thereby establishing their absolute biaryl axial chirality as P and M, respectively. In contrast to 1, metabolites 2-9 exhibited weak or no cytotoxic or lipoxygenase inhibitory effects. 相似文献
73.
Li B Bergmann J Lassen S Leonhard P Prange A 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,814(1):83-91
The distribution of silver, arsenic, cadmium, cobalt, chromium, copper, iron, manganese, nickel, lead, selenium and zinc binding to species with different molecular weight in aqueous extract of krill was studied by on-line size-exclusion chromatography (SEC)/inductively coupled plasma mass spectrometry (ICP-MS). The extract was fractionated in three fractions with different molecular weight (MW) ranges (>20,000 relative molecular mass (rel. mol. mass), 2000-20,000 rel. mol. mass and <2000 rel. mol. mass), which were further analyzed by SEC with columns having different optimum fractionation ranges in order to obtain more detailed information about the MW distribution of the elements. Various distribution profiles for the target elements among different MW ranges were observed. The results obtained indicated that manganese, zinc, silver, cadmium and lead species were mostly distributed in the higher MW range (>20,000 rel. mol. mass). In the case of chromium, iron, cobalt, arsenic and selenium, most of them bind to species with lower MW (<2000 rel. mol. mass). Only copper and nickel species was predominantly present in middle MW range (2000-20,000 rel. mol. mass). Further speciation of arsenic compounds in the small MW fraction was carried out with anion exchange chromatography (AEC) coupled with ICP-MS. The results showed that the dominant arsenic species in this fraction is As(III) (63% of extractable arsenic), while As(V) (13%) and two unknown arsenic species (19% and 5%, respectively) are present in lower amounts. 相似文献
74.
Kara G. Lassen 《Autophagy》2018,14(2):216-220
The discovery of numerous genetic variants in the human genome that are associated with inflammatory bowel disease (IBD) has revealed critical pathways that play important roles in intestinal homeostasis. These genetic studies have identified a critical role for macroautophagy/autophagy and more recently, lysosomal function, in maintaining the intestinal barrier and mucosal homeostasis. This review highlights recent work on the functional characterization of IBD-associated human genetic variants in cell type-specific functions for autophagy. 相似文献
75.
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77.
L?rke Münter Lassen Agnieszka Zygadlo Nielsen Carl Erik Olsen Wojciech Bialek Kenneth Jensen Birger Lindberg M?ller Poul Erik Jensen 《PloS one》2014,9(7)
Plants produce an immense variety of specialized metabolites, many of which are of high value as their bioactive properties make them useful as for instance pharmaceuticals. The compounds are often produced at low levels in the plant, and due to their complex structures, chemical synthesis may not be feasible. Here, we take advantage of the reducing equivalents generated in photosynthesis in developing an approach for producing plant bioactive natural compounds in a photosynthetic microorganism by functionally coupling a biosynthetic enzyme to photosystem I. This enables driving of the enzymatic reactions with electrons extracted from the photosynthetic electron transport chain. As a proof of concept, we have genetically fused the soluble catalytic domain of the cytochrome P450 CYP79A1, originating from the endoplasmic reticulum membranes of Sorghum bicolor, to a photosystem I subunit in the cyanobacterium Synechococcus sp. PCC 7002, thereby targeting it to the thylakoids. The engineered enzyme showed light-driven activity both in vivo and in vitro, demonstrating the possibility to achieve light-driven biosynthesis of high-value plant specialized metabolites in cyanobacteria. 相似文献
78.
Annika Wiebring Heike Helmholz Ilka Sötje Stephan Lassen Andreas Prange Henry Tiemann 《Marine biotechnology (New York, N.Y.)》2010,12(3):308-317
Jellyfish have an increasing impact on marine ecology. Cnidocysts bearing stinging cells afford, amongst others, prey capture
and defence. Several different types of stinging capsules are found in one species and they are supposed to have specific
functions, e.g. paralysing prey or adhering to it. Due to these assumed different roles of the capsules, it is suggested that
toxins, which are contained in the capsules, differ in composition. Analysis of distinct types of nematocysts requires an
appropriate method for the separation of the different types. Mixtures of types of nematocysts were obtained of two species
of jellyfish, Aurelia aurita and Cyanea lamarckii, by maceration of the tissue. These mixtures were treated with a method called laser microdissection and pressure catapulting
(LMPC). Optimized maceration methods, which were firstly introduced as a method for this purpose, in conjunction with optimized
LMPC parameters lead to sufficient amounts of separated capsules of individual types for subsequent mass-spectrometric analyses.
In case of A. aurita, the resulting mass spectra had some constituents in common, whereas in the overall pattern, the two distinct nematocyst
types differed. 相似文献
79.
Measurement of digital blood pressure after local cooling 总被引:3,自引:0,他引:3
80.
The chlorinated phenoxyacetic acids 2-methyl-4-chlorophenoxyacetic acid (MCPA), 2,4-dichlorophenoxyacetic acid (2,4-D), 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) and 2,4,5-T butoxyethyl ester and the chlorophenols 2,4-dichlorophenol and 2,4,5-trichlorophenol were tested for genotoxicity in the modified Allium test, which is based on exposure to the test chemicals of growing onions. The mean length of growing roots were measured and chromosome damage was recorded. Of the substances tested, MCPA was the most toxic and the chlorophenoxyacetic acids were more toxic than the chlorophenols. The lower threshold values for growth retardation were below 0.1 ppm for the acids, approx. at 0.1 ppm for the ester and less than 5 ppm for the phenols. Though a monocotyledon, Allium cepa was sensitive enough to respond to even low concentrations of these dicotyledon-selecting pesticides. 相似文献