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An infrared spectroscopic method for quantitative analysis of fatty alcohols and fatty acid esters in machinery oils.

https://arctichealth.org/en/permalink/ahliterature9130
Source
Anal Bioanal Chem. 2005 Sep;383(2):305-11
Publication Type
Article
Date
Sep-2005
Author
Pekka Vähäoja
Jani Närhi
Toivo Kuokkanen
Outi Naatus
Jorma Jalonen
Sulo Lahdelma
Author Affiliation
Department of Chemistry, University of Oulu, P.O. Box 3000, 90014, Oulu, Finland. Pekka.Vahaoja@oulu.fi
Source
Anal Bioanal Chem. 2005 Sep;383(2):305-11
Date
Sep-2005
Language
English
Publication Type
Article
Keywords
Carbon Disulfide - chemistry
Carbon Tetrachloride - chemistry
Comparative Study
Dodecanol - analysis
Esters - analysis
Fatty Acids - analysis
Fatty Alcohols - analysis
Palmitates - analysis
Plant Oils - chemistry
Research Support, Non-U.S. Gov't
Solvents - chemistry
Spectrophotometry, Infrared - methods
Stearates - analysis
Volatilization
Abstract
A new infrared spectroscopic method suitable for determining total fatty alcohol and fatty acid ester concentrations in industrial oils has been developed. Oil samples were diluted with toluene (1:3 w/w), the toxicity and volatility of which are relatively low compared with more commonly used IR solvents, like carbon tetrachloride or carbon disulfide. Mixture standards were prepared from dodecanol, tetradecanol, octadecanol, methyl stearate and methyl palmitate. Some analytical and statistical tests were performed on the developed method. The recoveries and the repeatability of the method proved to be sufficient for the quantitative determination of fatty alcohol and fatty acid ester additives in industrial oils. Reproducibility testing in another laboratory also produced satisfactory results. The developed method also proved to be relatively quick and simple. This method was developed to satisfy industry's need to determine the concentrations of these oil additives, and it has already been applied successfully in machinery oil analysis.
PubMed ID
16132128 View in PubMed
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[Bent dsDNA with defined geometric characteristics in terms of complexes of bridged oligonucleotides]

https://arctichealth.org/en/permalink/ahliterature88377
Source
Bioorg Khim. 2009 May-Jun;35(3):384-96
Publication Type
Article
Author
Vinogradova O A
Eremeeva E V
Lomzov A A
Pyshnaia I A
Pyshnyi D V
Author Affiliation
Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, pr. Lavrent' eva 8, Novosibirsk, 630090 Russia.
Source
Bioorg Khim. 2009 May-Jun;35(3):384-96
Language
Russian
Publication Type
Article
Keywords
DNA - chemical synthesis - chemistry
Electrophoresis, Polyacrylamide Gel
Ethylene Glycols - chemistry
Fatty Alcohols - chemistry
Furans - chemistry
Nucleic Acid Conformation
Nucleic Acid Denaturation
Nucleic Acid Heteroduplexes - chemistry
Oligonucleotides - chemistry
Phosphoric Acid Esters - chemistry
Abstract
An opportunity of designing nontypical double-stranded DNA structures containing nonnatural inserts in a regular nucleotide DNA sequence has been investigated. The looped nucleotide inserts on the basis of adenylates and thymidilates, and nonnucleotide inserts on the basis of phosphodiesters of diethyleneglycol, 1,10-decanediol, and 3-hydroxy-2-hudroxymethyltetrahydrofuran were introduced into the backbone of a 32-mer native DNA duplex. These inserts formed the internal loops in the modified double-stranded DNA fragments which were shown to lead to bending of the linear duplex structure by 16 to 83 degrees. The dependencies of the bend angle of dsDNA on the composition and the length of the looped regions were determined. It was established that the bend of the irregular region of dsDNA depended on the electrostatic interaction of the phosphate residues. The tension in the complex structure could be reduced by the introduction of additional nucleotide units opposite the loop, which led to some relaxation of the bent helix. The resulting parameters of the bend values were shown to be in a good agreement with the published data obtained by NMR spectroscopy. It was demonstrated that the variation of the nature or the length of the insert allowed one to regulate the level of the local perturbation of the duplex structure and, thereby, influence both the bend level of the double helix and the destabilization of the modified complex.
PubMed ID
19621054 View in PubMed
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Biomass and content of ginsenosides and polyacetylenes in American ginseng roots can be increased without affecting the profile of bioactive compounds.

https://arctichealth.org/en/permalink/ahliterature90805
Source
Nat Med (Tokyo). 2009 Apr;63(2):159-68
Publication Type
Article
Date
Apr-2009
Author
Christensen Lars P
Jensen Martin
Author Affiliation
Faculty of Engineering, Institute of Chemical Engineering, Biotechnology and Environmental Technology, University of Southern Denmark, Niels Bohrs Allé 1, Odense M, Denmark. lpc@kbm.sdu.dk
Source
Nat Med (Tokyo). 2009 Apr;63(2):159-68
Date
Apr-2009
Language
English
Publication Type
Article
Keywords
Chromatography, High Pressure Liquid
Denmark
Diynes - chemistry
Fatty Alcohols - chemistry
Genotype
Ginsenosides - chemistry
Panax - chemistry
Plant Extracts - chemistry
Plant Roots
Polyacetylenes - chemistry
Abstract
Fifty selected roots from a 7-year-old American ginseng (Panax quinquefolium L.) plant population grown in Denmark, with root weights varying from 191 to 490 g fresh weight (FW), were investigated for bioactive ginsenosides and polyacetylenes (PAs) in order to determine the correlation between the content of ginsenosides and PAs and root FW. PAs (falcarinol, panaxydol) and ginsenosides (Rb(1), Rb(2), Rb(3), Rc, Rd, Re, Rg(1)) were extracted from roots by sequential extraction with ethyl acetate and 80% methanol, respectively, and quantified in extracts by reverse-phase high-performance liquid chromatography (HPLC) using photodiode array detection. Total concentrations of PAs and ginsenosides varied between 150 and 780 mg/kg FW and 5,920 and 15,660 mg/kg FW, respectively. No correlation existed between the content of ginsenosides and PAs and root FW or between the total concentration of ginsenosides and PAs. Strong significant correlation was found between total content of ginsenosides and ginsenoside Rb(1) (r = 0.8190, P
PubMed ID
19085048 View in PubMed
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Characterisation of a new isolate of Mycobacterium shimoidei from Finland.

https://arctichealth.org/en/permalink/ahliterature196992
Source
J Med Microbiol. 2000 Oct;49(10):937-40
Publication Type
Article
Date
Oct-2000
Author
P. Koukila-Kähkölä
L. Paulin
E. Brander
E. Jantzen
M. Eho-Remes
M L Katila
Author Affiliation
Institute of Biotechnology, University of Helsinki, Finland. pirkko.koukila-kahkola@huch.fi
Source
J Med Microbiol. 2000 Oct;49(10):937-40
Date
Oct-2000
Language
English
Publication Type
Article
Keywords
Aged
Base Sequence
Chromatography, Gas
Chromatography, Thin Layer
DNA, Ribosomal - chemistry
Fatty Acids - analysis
Fatty Alcohols - analysis
Female
Finland
Humans
Molecular Sequence Data
Mycobacterium - chemistry - classification - genetics
Mycobacterium Infections - microbiology - pathology
Mycolic Acids - analysis
RNA, Ribosomal, 16S - genetics
Sequence Analysis, DNA
Sputum - microbiology
Abstract
This report describes the first isolation of Mycobacterium shimoidei in Finland from a sputum specimen obtained from an elderly female patient. M. shimoidei, a potential lung pathogen, is difficult to identify by routine methods and only a few cases have been reported. The present study demonstrated that M. shimoidei has a characteristic pattern for fatty acids and alcohols in gas liquid chromatography. This chromatogram and the pattern of mycolic acids on thin-layer chromatography allow it to be distinguished routinely. The unique sequence of the 16S rRNA gene and the 16S-23S rDNA spacer region allows identification by molecular methods.
PubMed ID
11023191 View in PubMed
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Dermatitis from common ivy (Hedera helix L. subsp. helix) in Europe: past, present, and future.

https://arctichealth.org/en/permalink/ahliterature99421
Source
Contact Dermatitis. 2010 Apr;62(4):201-9
Publication Type
Article
Date
Apr-2010
Author
Evy Paulsen
Lars P Christensen
Klaus E Andersen
Author Affiliation
Department of Dermatology, Odense University Hospital, University of Southern Denmark, Odense C, Denmark. evy.paulsen@ouh.regionsyddanmark.dk
Source
Contact Dermatitis. 2010 Apr;62(4):201-9
Date
Apr-2010
Language
English
Publication Type
Article
Keywords
Adolescent
Adult
Case-Control Studies
Cross Reactions
Denmark
Dermatitis, Allergic Contact - epidemiology
Dermatitis, Occupational - epidemiology
Diynes - immunology
Europe - epidemiology
Fatty Alcohols - immunology
Female
Hedera - toxicity
Humans
Male
Middle Aged
Patch Tests
Abstract
Common ivy (Hedera helix subsp. helix) is a well-known native and ornamental plant in Europe. Reports on contact dermatitis from ivy have regularly appeared since 1899. Recently, it has been suggested that allergic contact dermatitis from the plant may be under-diagnosed, partly due to lack of commercial patch test allergens. The objective of the article is to present the results of aimed patch testing with the main common ivy allergen, falcarinol, during a 16-year period and review the newer literature. Consecutive patients tested with falcarinol 0.03% petrolatum from May 1993 to May 2009 were included. Cases published since 1987 were retrieved from the PubMed database. One hundred and twenty-seven Danish patients were tested with falcarinol and 10 (7.9%) tested positive. Seven were occupationally sensitized. Between 1994 and 2009, 28 new cases of contact dermatitis from ivy were reported, 2 of which were occupational. Only 11 of the 28 patients were tested with pure allergens. Falcarinol is not only widely distributed in the ivy family, but also in the closely related Apiaceae. Sensitization may occur in childhood or in adults pruning ivy plants or handling them in an occupational setting. In view of the ubiquity of falcarinol-containing plants and the relatively high prevalence of positive reactions in aimed patch testing, falcarinol should be the next plant allergen to be commercially available and included in the plant series worldwide.
PubMed ID
20236156 View in PubMed
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Effect of surfactant interfacial orientation/aggregation on adsorption dynamics.

https://arctichealth.org/en/permalink/ahliterature10462
Source
Adv Colloid Interface Sci. 2000 May 24;86(1-2):83-101
Publication Type
Article
Date
May-24-2000
Author
V B Fainerman
R. Miller
E V Aksenenko
A V Makievski
J. Krägel
G. Loglio
L. Liggieri
Author Affiliation
International Medical Physicochemical Centre, Donetsk Medical University, Ukraine.
Source
Adv Colloid Interface Sci. 2000 May 24;86(1-2):83-101
Date
May-24-2000
Language
English
Publication Type
Article
Keywords
Adsorption
Fatty Alcohols - chemistry
Kinetics
Models, Theoretical
Oxides - chemistry
Phosphines - chemistry
Research Support, Non-U.S. Gov't
Surface-Active Agents - chemistry
Thermodynamics
Abstract
The application of new thermodynamic adsorption isotherms allow to improve the description of surfactant adsorption kinetics based on a diffusional transport. While the consideration of interfacial reorientation corrects apparently too high diffusion coefficients, interfacial aggregation avoids too small diffusion coefficients or the assumption of adsorption barriers. The adsorption kinetics of alkyl dimethyl phosphine oxides is influenced by interfacial reorientation. While the lower homologues (C8-C12) follow the classical diffusion model, the higher homologues (C13-C15) yield diffusion coefficients several times larger than the physically reasonable values. Assuming two different adsorption states, the resulting diffusion coefficients agree with those expected from the geometric size of the molecules. The model also works well for oxyethylated non-ionics, such as C10EO8. As a second example, a good theoretical description is obtained for experiments of 1-decanol solutions when a mean surface aggregation number of n = 2.5 is assumed. The same n was obtained from the description of the equilibrium adsorption isotherm of 1-decanol. Assuming that the transition from one into the other state is controlled by a rate constant (change in orientation, formation or disintegration of two-dimensional aggregates) significant changes in the kinetics curves can result. The use of additional rate constants yields an improved fitting to experimental data.
PubMed ID
10798351 View in PubMed
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Effect of the selective leukotriene B4 antagonists U-75302 and Ly255283 on bronchoalveolar eosinophilia induced by inhalation of leukotriene B4 or allergen in brown-Norway rats.

https://arctichealth.org/en/permalink/ahliterature12109
Source
Ann N Y Acad Sci. 1991;629:428-9
Publication Type
Article
Date
1991

20 records – page 1 of 2.