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6399 records – page 1 of 640.

1,3-Butadiene and leukemia among synthetic rubber industry workers: exposure-response relationships.

https://arctichealth.org/en/permalink/ahliterature166384
Source
Chem Biol Interact. 2007 Mar 20;166(1-3):15-24
Publication Type
Article
Date
Mar-20-2007
Author
Hong Cheng
Nalini Sathiakumar
John Graff
Robert Matthews
Elizabeth Delzell
Author Affiliation
University of Alabama at Birmingham, Ryals School of Public Health, Department of Epidemiology, Birmingham, AL, USA. hcheng@ms.soph.uab.edu
Source
Chem Biol Interact. 2007 Mar 20;166(1-3):15-24
Date
Mar-20-2007
Language
English
Publication Type
Article
Keywords
Butadienes - adverse effects
Canada - epidemiology
Carcinogens - chemical synthesis - chemistry - toxicity
Chemical Industry - manpower - statistics & numerical data
Confidence Intervals
Dimethyldithiocarbamate - adverse effects
Humans
Leukemia, Lymphoid - chemically induced - epidemiology
Leukemia, Myeloid - chemically induced - epidemiology
Likelihood Functions
Male
Middle Aged
Occupational Exposure - statistics & numerical data
Proportional Hazards Models
Rubber - adverse effects - chemical synthesis - chemistry
United States - epidemiology
Abstract
Previous research updated the mortality experience of North American synthetic rubber industry workers during the period 1944-1998, determined if leukemia and other cancers were associated with several employment factors and carried out Poisson regression analysis to examine exposure-response associations between estimated exposure to 1,3-butadiene (BD) or other chemicals and cancer. The present study used Cox regression procedures to examine further the exposure-response relationship between several unlagged and lagged, continuous, time-dependent BD exposure indices (BD parts per million (ppm)-years, the total number of exposures to BD concentrations >100 ppm ("peaks") and average intensity of BD) and leukemia, lymphoid neoplasms and myeloid neoplasms. All three BD exposure indices were associated positively with leukemia. Using continuous, untransformed BD ppm-years the regression coefficient (beta) from an analysis that controlled only for age was 2.9 x 10(-4) (p
PubMed ID
17123495 View in PubMed
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The 1.9 A crystal structure of heat-labile shrimp alkaline phosphatase.

https://arctichealth.org/en/permalink/ahliterature189601
Source
J Mol Biol. 2002 May 17;318(5):1265-74
Publication Type
Article
Date
May-17-2002
Author
Maaike de Backer
Sean McSweeney
Hanne B Rasmussen
Bjørn W Riise
Peter Lindley
Edward Hough
Author Affiliation
European Synchrotron Radiation Facility, Grenoble, France.
Source
J Mol Biol. 2002 May 17;318(5):1265-74
Date
May-17-2002
Language
English
Publication Type
Article
Keywords
Alkaline Phosphatase - chemistry
Animals
Crystallography, X-Ray
Decapoda (Crustacea) - chemistry - enzymology
Humans
Models, Molecular
Protein Conformation
Temperature
Abstract
Alkaline phosphatases are non-specific phosphomonoesterases that are distributed widely in species ranging from bacteria to man. This study has concentrated on the tissue-nonspecific alkaline phosphatase from arctic shrimps (shrimp alkaline phosphatase, SAP). Originating from a cold-active species, SAP is thermolabile and is used widely in vitro, e.g. to dephosphorylate DNA or dNTPs, since it can be inactivated by a short rise in temperature. Since alkaline phosphatases are zinc-containing enzymes, a multiwavelength anomalous dispersion (MAD) experiment was performed on the zinc K edge, which led to the determination of the structure to a resolution of 1.9 A. Anomalous data clearly showed the presence of a zinc triad in the active site, whereas alkaline phosphatases usually contain two zinc and one magnesium ion per monomer. SAP shares the core, an extended beta-sheet flanked by alpha-helices, and a metal triad with the currently known alkaline phosphatase structures (Escherichia coli structures and a human placental structure). Although SAP lacks some features specific for the mammalian enzyme, their backbones are very similar and may therefore be typical for other higher organisms. Furthermore, SAP possesses a striking feature that the other structures lack: surface potential representations show that the enzyme's net charge of -80 is distributed such that the surface is predominantly negatively charged, except for the positively charged active site. The negatively charged substrate must therefore be directed strongly towards the active site. It is generally accepted that optimization of the electrostatics is one of the characteristics related to cold-adaptation. SAP demonstrates this principle very clearly.
PubMed ID
12083516 View in PubMed
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1 H NMR study and multivariate data analysis of reindeer skin tanning methods.

https://arctichealth.org/en/permalink/ahliterature291047
Source
Magn Reson Chem. 2017 Apr; 55(4):312-317
Publication Type
Journal Article
Date
Apr-2017
Author
Lizheng Zhu
Andrew J Ilott
Eleonora Del Federico
Cindie Kehlet
Torunn Klokkernes
Alexej Jerschow
Author Affiliation
Department of Chemistry, New York University, New York, NY, USA.
Source
Magn Reson Chem. 2017 Apr; 55(4):312-317
Date
Apr-2017
Language
English
Publication Type
Journal Article
Keywords
Animals
Humans
Magnetic Resonance Spectroscopy
Multivariate Analysis
Plant Extracts - chemistry
Reindeer
Seasons
Skin - chemistry
Tanning - methods
Tannins - chemistry
Vegetables - chemistry
Abstract
Reindeer skin clothing has been an essential component in the lives of indigenous people of the arctic and sub-arctic regions, keeping them warm during harsh winters. However, the skin processing technology, which often conveys the history and tradition of the indigenous group, has not been well documented. In this study, NMR spectra and relaxation behaviors of reindeer skin samples treated with a variety of vegetable tannin extracts, oils and fatty substances are studied and compared. With the assistance of principal component analysis (PCA), one can recognize patterns and identify groupings of differently treated samples. These methods could be important aids in efforts to conserve museum leather artifacts with unknown treatment methods and in the analysis of reindeer skin tanning processes. Copyright © 2016 John Wiley & Sons, Ltd.
PubMed ID
27654838 View in PubMed
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2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) poisoning in Victor Yushchenko: identification and measurement of TCDD metabolites.

https://arctichealth.org/en/permalink/ahliterature95137
Source
Lancet. 2009 Oct 3;374(9696):1179-85
Publication Type
Article
Date
Oct-3-2009
Author
Sorg O.
Zennegg M.
Schmid P.
Fedosyuk R.
Valikhnovskyi R.
Gaide O.
Kniazevych V.
Saurat J-H
Author Affiliation
Dermato-Toxicology, Swiss Centre for Applied Human Toxicology, and Department of Dermatology, University Hospital, Geneva, Switzerland.
Source
Lancet. 2009 Oct 3;374(9696):1179-85
Date
Oct-3-2009
Language
English
Publication Type
Article
Keywords
Adipose Tissue - chemistry
Biopsy
Drug Residues - analysis - metabolism
Fatal Outcome
Feces - chemistry
Forensic Medicine - methods
Half-Life
Homicide
Humans
Male
Middle Aged
Politics
Substance Abuse Detection - methods
Sweat - chemistry
Tetrachlorodibenzodioxin - analysis - chemistry - metabolism - poisoning
Time Factors
Ukraine
Abstract
BACKGROUND: 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has a long half-life of 5-10 years in human beings as a result of its high lipophilicity, and little or no metabolism. We monitored TCDD, its form, distribution, and elimination in Victor Yushchenko after he presented with severe poisoning. METHODS: In late December, 2004, a patient presented with TCDD poisoning; the levels in his blood serum (108000 pg/g lipid weight) were more than 50 000-fold greater than those in the general population. We identified TCDD and its metabolites, and monitored their levels for 3 years using gas chromatography and high-resolution mass spectrometry in samples of blood serum, adipose tissue, faeces, skin, urine, and sweat, after they were extracted and cleaned with different organic solvents. FINDINGS: The amount of unmodified TCDD in the samples that were analysed accounted for about 60% of TCDD eliminated from the body during the same period. Two TCDD metabolites-2,3,7-trichloro-8-hydroxydibenzo-p-dioxin and 1,3,7,8-tetrachloro-2-hydroxydibenzo-p-dioxin-were identified in the faeces, blood serum, and urine. The faeces contained the highest concentration of TCDD metabolites, and were the main route of elimination. Altogether, the different routes of elimination of TCDD and its metabolites accounted for 98% of the loss of the toxin from the body. The half-life of TCDD in our patient was 15.4 months. INTERPRETATION: This case of poisoning with TCDD suggests that the design of methods for routine assessment of TCDD metabolites in human beings should be a main aim of TCDD research in the metabolomic era. FUNDING: University of Geneva Dermatology Fund, and Swiss Centre for Applied Human Toxicology.
Notes
Comment In: Lancet. 2009 Oct 3;374(9696):1131-219660808
PubMed ID
19660807 View in PubMed
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[2nd place in the contest for young scientists on gastroenterology in the 17th Congress "Man and Medicine" (April 2010, Moscow). Erosive esophagitis in children: characteristics of 24-hour pH monitoring in the the esophagus].

https://arctichealth.org/en/permalink/ahliterature146414
Source
Eksp Klin Gastroenterol. 2010;(9):129-36
Publication Type
Article
Date
2010

2-substituted 1,2-dihydro-3H-dibenz[de,h]isoquinoline-1,3-diones. A new class of antitumor agent.

https://arctichealth.org/en/permalink/ahliterature24099
Source
J Med Chem. 1993 Mar 19;36(6):765-70
Publication Type
Article
Date
Mar-19-1993
Author
S M Sami
R T Dorr
D S Alberts
W A Remers
Author Affiliation
Department of Pharmaceutical Sciences and Cancer Center, University of Arizona, Tucson 85721.
Source
J Med Chem. 1993 Mar 19;36(6):765-70
Date
Mar-19-1993
Language
English
Publication Type
Article
Keywords
Animals
Antineoplastic Agents - chemical synthesis - chemistry - therapeutic use
Female
Humans
Isoquinolines - chemical synthesis - chemistry - therapeutic use
Leukemia L1210 - drug therapy
Leukemia P388 - drug therapy
Male
Melanoma, Experimental - drug therapy
Mice
Mice, Inbred DBA
Ovarian Neoplasms - drug therapy
Research Support, U.S. Gov't, P.H.S.
Structure-Activity Relationship
Tumor Cells, Cultured - drug effects
Abstract
A new class of antitumor agents, having structural analogy to amonafide, but differing by the addition of a fourth ring in the nucleus, was synthesized conveniently from anthracene. Compounds with a variety of substituents, containing a basic nitrogen atom and located on the imide nitrogen, were prepared. Thirteen of 19 new compounds had greater growth inhibitory potency than amonafide in a panel of cultured murine and human tumor cells using the sulforhodamine B and MTT dye assays. The most active agents were similarly more toxic than amonafide to normal neonatal rat myocytes in vitro, but they had better chemotherapeutic indexes. From these compounds, the one with a 2-(dimethylamino)ethyl side chain (named azonafide) was chosen for further study. It showed high potency against a panel of cultured human colon cancer cells and it was active against ip P388 leukemia and subcutaneous B16 melanoma in mice. Preliminary structure-activity correlations suggest that the basicity of the side-chain nitrogen and the length of side chain are important determinants of antitumor potency in vitro. Steric hindrance and rigidity of the side chains might be other determinants.
PubMed ID
8459403 View in PubMed
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2-year clinical performance of a fluoride-containing fissure sealant in young schoolchildren at caries risk.

https://arctichealth.org/en/permalink/ahliterature34233
Source
Am J Dent. 1997 Jun;10(3):115-9
Publication Type
Article
Date
Jun-1997
Author
A. Carlsson
M. Petersson
S. Twetman
Author Affiliation
Public Dental Clinic, Vallås, Sweden.
Source
Am J Dent. 1997 Jun;10(3):115-9
Date
Jun-1997
Language
English
Publication Type
Article
Keywords
Analysis of Variance
Cariostatic Agents - analysis - therapeutic use
Chi-Square Distribution
Child
Colony Count, Microbial
Composite Resins - chemistry - therapeutic use
Dental Caries - epidemiology - prevention & control
Dental Plaque - microbiology
Fluorides - analysis - pharmacology - therapeutic use
Humans
Lactobacillus - drug effects - isolation & purification
Pit and Fissure Sealants - therapeutic use
Prevalence
Risk assessment
Saliva - chemistry - microbiology
Statistics, nonparametric
Streptococcus mutans - drug effects - isolation & purification
Sweden - epidemiology
Abstract
PURPOSE: To evaluate the clinical performance of Helioseal-F, a fluoride-containing fissure sealant, in school children at caries risk. MATERIALS AND METHODS: A caries risk assessment based on past caries experience, saliva microbial tests, buffer capacity and frequency of sugar intake was carried out in 204 healthy children, 6-7 years of age. Children exhibiting one or more risk factors were considered at caries risk (n = 121) and their permanent molars were sealed with a fluoride-containing fissure sealant, thus forming a fissure sealant group (FSG). The remaining 83 children with low caries risk received no fissure sealants and constituted a reference group (RG). Both groups were followed for 2 years. From 15 children of both groups, unstimulated whole saliva was collected 1 month after sealant placement in order to determine fluoride levels. In another 20 children, a split-mouth study design was utilized to compare the colonization of mutans streptococci adjacent to and on F-containing sealants and conventional controls. The sealants were placed by dental hygienists according to the manufacturers' instructions. RESULTS: A total of 431 fissure sealants were placed at baseline. Complete retention was found in 76.6% during the study period while 22.0% were partially lost. Six sealants (1.4%) were completely lost. The enamel caries incidence was 45% lower (P
PubMed ID
9545884 View in PubMed
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3-D modeling substantiates perfluorinated theory.

https://arctichealth.org/en/permalink/ahliterature82705
Source
Environ Sci Technol. 2006 Feb 1;40(3):632-3
Publication Type
Article
Date
Feb-1-2006
Author
Renner Rebecca
Source
Environ Sci Technol. 2006 Feb 1;40(3):632-3
Date
Feb-1-2006
Language
English
Publication Type
Article
Keywords
Air Movements
Alcohols
Arctic Regions
Environmental Pollutants - analysis
Fluorocarbons - analysis - chemistry
Industry
Manufactured Materials
Models, Theoretical
Octanoic Acids - analysis - chemistry
Notes
Comment On: Environ Sci Technol. 2006 Feb 1;40(3):924-3016509338
PubMed ID
16509290 View in PubMed
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The 3-hydroxyacyl-ACP dehydratase of mitochondrial fatty acid synthesis in Trypanosoma brucei.

https://arctichealth.org/en/permalink/ahliterature87070
Source
FEBS Lett. 2008 Mar 5;582(5):729-33
Publication Type
Article
Date
Mar-5-2008
Author
Autio Kaija J
Guler Jennifer L
Kastaniotis Alexander J
Englund Paul T
Hiltunen J Kalervo
Author Affiliation
Department of Biochemistry and Biocenter Oulu, University of Oulu, Oulu, Finland. kaija.autio@oulu.fi
Source
FEBS Lett. 2008 Mar 5;582(5):729-33
Date
Mar-5-2008
Language
English
Publication Type
Article
Keywords
Amino Acid Sequence
Animals
Electrophoresis
Fatty Acids - biosynthesis
Genetic Complementation Test
Humans
Hydro-Lyases - chemistry - isolation & purification - metabolism
Mitochondria - enzymology
Molecular Sequence Data
Protein Transport
Recombinant Fusion Proteins - isolation & purification - metabolism
Saccharomyces cerevisiae - cytology - metabolism
Sequence Alignment
Thioctic Acid - metabolism
Trypanosoma brucei brucei - cytology - enzymology
Abstract
The trypanosomatid parasite Trypanosoma brucei synthesizes fatty acids in the mitochondrion using the type II fatty acid synthesis (FAS) machinery. When mitochondrial FAS was characterized in T. brucei, all of the enzymatic components were identified based on their homology to yeast mitochondrial FAS enzymes, except for 3-hydroxyacyl-ACP dehydratase. Here we describe the characterization of T. brucei mitochondrial 3-hydroxyacyl-ACP dehydratase (TbHTD2), which was identified by its similarity to the human mitochondrial dehydratase. TbHTD2 can rescue the respiratory deficient phenotype of the yeast knock-out strain and restore the lipoic acid content, is localized in the mitochondrion and exhibits hydratase 2 activity.
PubMed ID
18258193 View in PubMed
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A 3-year follow-up study of preformed beta-quartz glass-ceramic insert restorations.

https://arctichealth.org/en/permalink/ahliterature195752
Source
Quintessence Int. 2000 Jan;31(1):25-31
Publication Type
Article
Date
Jan-2000
Author
G. Sjögren
S O Hedlund
C. Jonsson
A. Sandström
Author Affiliation
Department of Dental Materials Science, Umeå University, SE-901 87 Umeå, Sweden. Goran.Sjogren@odont.umu.se
Source
Quintessence Int. 2000 Jan;31(1):25-31
Date
Jan-2000
Language
English
Publication Type
Article
Keywords
Adult
Aged
Aged, 80 and over
Bicuspid
Ceramics - chemistry
Color
Dental Caries - classification
Dental Marginal Adaptation
Dental Plaque - classification
Dental Restoration Failure
Dental Restoration, Permanent - classification
Female
Follow-Up Studies
Gingival Hemorrhage - classification
Glass - chemistry
Humans
Inlays - classification
Male
Middle Aged
Molar
Quartz - chemistry
Surface Properties
Survival Analysis
Time Factors
Treatment Outcome
Abstract
The purpose of this study was to evaluate the clinical performance of preformed beta-quartz glass-ceramic insert restorations.
Nine Class I and 30 Class II beta-quartz glass-ceramic insert restorations were placed in 16 patients who were seen regularly by personnel at Umeå University Dental School. The California Dental Association criteria were used to evaluate the restorations at baseline, 6 months, and 1, 2, and 3 years after luting. The occurrence of postoperative sensitivity, the time taken to manufacture each restoration, and certain periodontal conditions were also evaluated.
Sixty-nine percent of the restorations were rated satisfactory at the 3-year examination. During the follow-up period, 4 became loose and 7 were fractured or had flaking surfaces. Caries was registered in connection with 1 restoration. Excellent ratings were obtained for marginal integrity, anatomic form, surface, and color in 62%, 84%, 32%, and 44% of the restorations, respectively. There was no statistically significant difference in the occurrence of plaque and bleeding on probing in comparison with the controls. The mean overall time for placement was 38 minutes. The estimated survival rate (Kaplan-Meier) was 59% after 3.5 years.
The quality of the beta-quartz glass-ceramic restorations in the present study was inferior to that presented in most earlier studies of ceramic or resin composite posterior restorations placed in patients treated at university clinics. Both the technique and the beta-quartz glass-ceramic inserts have to be evaluated in more long-term studies to assess the possibility of their serving as an alternative restorative technique.
PubMed ID
11203902 View in PubMed
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6399 records – page 1 of 640.