Skip header and navigation

Refine By

116 records – page 1 of 12.

Accumulation of cadmium in livers and kidneys in Greenlanders.

https://arctichealth.org/en/permalink/ahliterature80673
Source
Sci Total Environ. 2006 Dec 15;372(1):58-63
Publication Type
Article
Date
Dec-15-2006
Author
Johansen Poul
Mulvad Gert
Pedersen Henning Sloth
Hansen Jens C
Riget Frank
Author Affiliation
National Environmental Research Institute, Frederiksborgvej 399, DK-4000 Roskilde, Denmark. poj@dmu.dk
Source
Sci Total Environ. 2006 Dec 15;372(1):58-63
Date
Dec-15-2006
Language
English
Publication Type
Article
Keywords
Adult
Aged
Aged, 80 and over
Biological Availability
Cadmium - metabolism
Environmental monitoring
Environmental Pollutants - metabolism
Female
Food Contamination
Greenland
Humans
Kidney Cortex - metabolism
Liver - metabolism
Male
Middle Aged
Smoking
Abstract
In the Arctic, the traditional diet exposes its people to a very high intake of cadmium because it is highly concentrated in the liver and kidneys of commonly eaten marine mammals. In one study in Greenland, the cadmium intake was estimated to 182 microg/day/person in the fall and 346 in the spring. To determine whether the cadmium is accumulated in humans, we analyzed autopsy samples of liver and kidneys from 95 ethnic Greenlanders (aged 19-89) who died from a wide range of causes. The cadmium concentration in liver (overall mean 1.97 microg/g wet wt) appeared to be unrelated to any particular age group, whereas the concentrations in the kidneys peaked in Greenlanders between 40 and 50 years of age (peak concentration 22.3 microg/g wet wt). Despite the high cadmium levels in the typical Greenlander diet, we found that the cadmium concentrations in livers and kidneys were comparable to those reported from Denmark, Sweden, Australia and Great Britain. Furthermore, even though the mean cadmium intake from the diet was estimated to be 13-25 times higher in Greenlanders than in Danes, we found similar cadmium levels in the kidneys of both. Seal livers and kidneys are the main source of cadmium in the diet of Greenlanders, but these tissues are not eaten in Denmark. Thus, our results suggest that the accumulation of cadmium from Greenlander's marine diet is very low.
PubMed ID
16970977 View in PubMed
Less detail

Adaptogenic activity of a complex biomedication based on a northern renewable raw material.

https://arctichealth.org/en/permalink/ahliterature273839
Source
Wiad Lek. 2016;69(1 Pt 2):55-60
Publication Type
Article
Date
2016
Author
Vera V Anshakova
Albina V Stepanova
Dimitrii M Uvarov
Aigerim Sh Smagulova
Ksenia N Naumova
Petr P Vasiliev
Source
Wiad Lek. 2016;69(1 Pt 2):55-60
Date
2016
Language
English
Publication Type
Article
Keywords
Animals
Biological Availability
Exercise - physiology
Humans
Lichens - chemistry
Mice
Phytotherapy
Plant Extracts - pharmacokinetics
Rhodiola - chemistry
Russia
Swimming - physiology
Abstract
One of the methods of increasing bioavailability, and thus the therapeutic effectiveness of an active substances, along with decreasing its required dosage, is to generate highly effective "carrier: active substances" complexes where the active carrier both increases the bioavailability of the active substance at lower doses and has a detoxifying activity.
the aim of this work was study the properties of the carrier from the lichen thallome in both its solid pharmaceutical form and in combination with Rhodiola rosea.
the physiologically active plant extracts with enhanced adaptogenic pharmacological activity based on plant substances growing in Yakutia: Cladonia lichen thalli and Rhodiola rosea (Rhodiolarosea, fam.Crassulaceae) rhizomes, combined in a raw material dry-weight ratio of 10:1 We used a one step, solvent-free process, involving the use of mechanochemical ball mills relying on centrifugal acceleration of the 10-30 g grinding bodies.
A single-stage mechanochemical technology has been developed for obtaining highly effective solid-phase biocomplexes based on a"multipurpose active filler" - a polymer matrix of lichen ?-oligosaccharides. It has been shown that lichen, is a raw material from which can be sourced a filler with a strong adsorption activity for solid pharmaceutical forms.
It is considered statistically significant that a bicomponent plant mechanocomplex based on this filler - lichen ?-oligosaccharides and small amounts of Rhodiola rosea has a wide spectrum of adaptogenic action, increasing the resistance of laboratory animals to the effects of physical exercise and a variety of extreme factors.
PubMed ID
27164277 View in PubMed
Less detail

Addressing arsenic bioaccessibility in ecological risk assessment: a novel approach to avoid overestimating risk.

https://arctichealth.org/en/permalink/ahliterature91571
Source
Environ Toxicol Chem. 2009 Mar;28(3):668-75
Publication Type
Article
Date
Mar-2009
Author
Ollson Christopher A
Koch Iris
Smith Paula
Knopper Loren D
Hough Chris
Reimer Ken J
Author Affiliation
Jacques Whitford, Burlington, Ontario, Canada.
Source
Environ Toxicol Chem. 2009 Mar;28(3):668-75
Date
Mar-2009
Language
English
Publication Type
Article
Keywords
Animals
Arsenic - chemistry - pharmacokinetics
Biological Availability
Environmental Monitoring - methods
Industrial Waste
Mining
Northwest Territories
Peromyscus
Risk assessment
Soil Pollutants - chemistry - pharmacokinetics
Trees
Abstract
The risk of arsenic exposure to deer mice (Peromyscus maniculatus) living in areas of naturally and anthropogenically elevated arsenic levels was determined using three separate calculations of arsenic daily intake: Estimated daily intake (EDI), bioaccessible EDI (BEDI), and actual daily intake (ADI). The present work is of particular interest, because the risk assessments were determined for animals naturally exposed to arsenic. Gastric fluid extraction was used to obtain bioaccessibility data for soil and plant samples collected from three study sites (background, mine forest, and tailings) in Yellowknife (NT, Canada). Calculations using the EDI indicated that deer mice living in tailings habitat (average soil arsenic concentration, 1,740 +/- 2,240 microg/g) should have been experiencing serious health effects as a result of their exposure to arsenic. Using BEDI and ADI in the risk assessment calculation, however, resulted in an order-of-magnitude decrease in calculated risk. In addition, results calculated using the BEDI and ADI were not significantly different, suggesting that using bioaccessibility provides a more realistic estimate of potential risk. The present results provide evidence that the use of EDI in traditional risk assessments may seriously overestimate the actual risk, which in some instances may result in expensive and unnecessary clean-up measures.
PubMed ID
18939889 View in PubMed
Less detail

Adjustment of iron intake for dietary enhancers and inhibitors in population studies: bioavailable iron in rural and urban residing Russian women and children.

https://arctichealth.org/en/permalink/ahliterature207882
Source
J Nutr. 1997 Aug;127(8):1456-68
Publication Type
Article
Date
Aug-1997
Author
M. Tseng
H. Chakraborty
D T Robinson
M. Mendez
L. Kohlmeier
Author Affiliation
Department of Epidemiology, University of North Carolina, Chapel Hill, NC 27599, USA.
Source
J Nutr. 1997 Aug;127(8):1456-68
Date
Aug-1997
Language
English
Publication Type
Article
Keywords
Adolescent
Adult
Aged
Biological Availability
Child
Child, Preschool
Databases, Factual
Diet
Female
Heme - metabolism
Humans
Infant
Intestinal Absorption
Iron, Dietary - administration & dosage - pharmacokinetics
Male
Middle Aged
Nutritional Requirements
Rural Population
Russia
Urban Population
Abstract
Although determining iron intakes is essential in assessing adequacy of iron in the diet, estimating iron availability may be more useful for evaluating whether iron requirements are met. Our objectives were to describe the dietary information, analytical steps, and computer algorithms needed for iron bioavailability adjustments and to demonstrate the effects of various dietary factors on calculated iron absorption. Our study was based on 9890 women and children participating in the Russian Longitudinal Monitoring Survey. Between August 1992 and February 1993, two 24-h recalls were collected from each participant, and total, heme and nonheme iron intakes were calculated. Nonheme iron availability was adjusted for meat, fish and poultry and vitamin C consumed in the same meal and then further adjusted for tea and phytates. We found mean total iron intakes to be comparable to those of women of reproductive age in the United States and lower than those of United States children. When these intakes were adjusted for enhancers and inhibitors of absorption, the iron bioavailability in these vulnerable Russian groups was extremely low. Mean bioavailable iron as well as the 25th-75th percentile ranges of intake were below the bottom of the range of requirements, indicating that iron adequacy in this population may be considerably less than expected based on total iron intakes alone. Furthermore, rural and urban food availability had a significant effect on iron bioavailability. Future research on dietary iron adequacy should be based on estimates of available iron by collecting meal-level dietary data and using detailed information on mixed dishes and phytates.
PubMed ID
9237938 View in PubMed
Less detail

Adrenal suppression in asthmatic children receiving low-dose inhaled budesonide: comparison between dry powder inhaler and pressurized metered-dose inhaler attached to a spacer.

https://arctichealth.org/en/permalink/ahliterature15304
Source
Ann Allergy Asthma Immunol. 2002 Dec;89(6):566-71
Publication Type
Article
Date
Dec-2002
Author
Shmuel Goldberg
Tsurit Einot
Nurit Algur
Shimshon Schwartz
Alan C Greenberg
Elie Picard
Dov Virgilis
Eitan Kerem
Author Affiliation
Department of Pediatric Respiratory Medicine, Shaare Zedek Medical Center, Hebrew University Medical School, Jerusalem, Israel.
Source
Ann Allergy Asthma Immunol. 2002 Dec;89(6):566-71
Date
Dec-2002
Language
English
Publication Type
Article
Keywords
Absorption
Administration, Inhalation
Adolescent
Adrenal Cortex - secretion
Aerosols
Anti-Asthmatic Agents - administration & dosage - adverse effects - pharmacology
Biological Availability
Budesonide - administration & dosage - adverse effects - pharmacology
Child
Child, Preschool
Comparative Study
Cross-Over Studies
Depression, Chemical
Female
Humans
Hydrocortisone - secretion - urine
Hypothalamo-Hypophyseal System - drug effects
Inhalation Spacers
Lung - metabolism
Male
Pituitary-Adrenal System - drug effects
Powders
Abstract
BACKGROUND: Dry powder inhalers (DPI) have in recent years become a common mode for administration of inhaled corticosteroids for preventive therapy of asthma. Inhaled steroids delivered by DPI achieve increased lung deposition compared with pressurized metered-dose inhalers (pMDI), which is associated with increased therapeutic effect. This may be associated with increased systemic absorption. OBJECTIVE: The purpose of this study was to evaluate the prevalence of adrenal suppression in children using low-dose budesonide given by DPI, as compared with pMDI attached to a large-volume spacer device (pMDI + spacer). METHODS: In an open-labeled crossover study, 15 asthmatic children aged 5 to 15 years received 200 microg of inhaled budesonide twice daily by DPI (Turbuhaler, Astra, Draco AB, Lund, Sweden) and by pMDI + spacer, 1 month each, in a randomized order. Twenty-four-hour urine collections were performed at baseline and at the end of each of the 2 months of the study period, and urinary cortisol and creatinine were measured. RESULTS: Baseline urinary cortisol:creatinine was 0.038 +/- 0.012 microg/mg, similar in both groups. After 1 month of DPI therapy, urinary cortisol:creatinine was reduced by 27 +/- 16% to 0.028 +/- 0.012 microg/mg (P = 0.018). Urinary cortisol:creatinine after 1 month of pMDI + spacer therapy was similar to baseline 0.037 +/- 0.019 microg/mg (P = 0.78). CONCLUSIONS: Treatment of asthmatic children with budesonide 400 microg daily given via a DPI for 1 month was associated with hypothalamic-pituitary-adrenal axis suppression. This effect was not observed with the same dose of budesonide administered via pMDI + spacer. This indicates that systemic absorption might be reduced with pMDI + spacer therapy.
Notes
Comment In: Ann Allergy Asthma Immunol. 2002 Dec;89(6):537-912487216
Comment In: Ann Allergy Asthma Immunol. 2003 Jun;90(6):674; author reply 674-512839330
PubMed ID
12487221 View in PubMed
Less detail

Aerobic power declines with aging in rat skeletal muscles perfused at matched convective O2 delivery.

https://arctichealth.org/en/permalink/ahliterature49786
Source
J Appl Physiol. 2003 Feb;94(2):744-51
Publication Type
Article
Date
Feb-2003
Author
Russell T Hepple
Jason L Hagen
Daniel J Krause
Cory C Jackson
Author Affiliation
Faculty of Kinesiology and Faculty of Medicine, University of Calgary, Alberta, Canada T2N 1N4. hepple@ucalgary.ca
Source
J Appl Physiol. 2003 Feb;94(2):744-51
Date
Feb-2003
Language
English
Publication Type
Article
Keywords
Aerobiosis
Aging - physiology
Animals
Biological Availability
Hindlimb
Muscle Contraction
Muscle, Skeletal - blood supply - metabolism - physiology
Oxidation-Reduction
Oxygen - blood
Oxygen consumption
Rats
Rats, Inbred BN
Rats, Inbred F344
Research Support, Non-U.S. Gov't
Abstract
Although it is well established that maximal O(2) uptake (Vo(2 max)) declines from adulthood to old age, the role played by alterations in skeletal muscle is unclear. Specifically, because during whole body exercise reductions in convective O(2) delivery to the working muscles from adulthood to old age compromise aerobic performance, this obscures the influence of alterations within the skeletal muscles. We sought to overcome this limitation by using an in situ pump-perfused hindlimb preparation to permit matching of muscle convective O(2) delivery in young adult (8 mo; muscle convective O(2) delivery = 569 +/- 42 micromol O(2) x min(-1) x 100 g(-1)) and late middle-aged (28-30 mo; 539 +/- 62 micromol O(2) x min(-1) x 100 g(-1)) Fischer 344 x Brown Norway F1 hybrid rats. The distal hindlimb muscles were electrically stimulated for 4 min (60 tetani/min), and Vo(2 max) was determined. Vo(2 max) normalized to the contracting muscle mass was 22% lower in the 28- to 30-mo-old (344 +/- 17 micromol O(2). min(-1) x 100 g(-1)) than the 8-mo-old (441 +/- 20 micromol O(2) x min(-1) x 100 g(-1); P
PubMed ID
12391069 View in PubMed
Less detail

Aging reveals a role for nigral tyrosine hydroxylase ser31 phosphorylation in locomotor activity generation.

https://arctichealth.org/en/permalink/ahliterature98503
Source
PLoS One. 2009;4(12):e8466
Publication Type
Article
Date
2009
Author
Michael F Salvatore
Brandon S Pruett
Sandy L Spann
Charles Dempsey
Author Affiliation
Department of Pharmacology, Toxicology, and Neuroscience, Louisiana State University Health Sciences Center, Shreveport, Louisiana, USA. msalva@lsuhsc.edu
Source
PLoS One. 2009;4(12):e8466
Date
2009
Language
English
Publication Type
Article
Keywords
Aging - metabolism
Animals
Biological Availability
Dopamine - metabolism
Longevity
Motor Activity - physiology
Phosphorylation
Phosphoserine - metabolism
Population Dynamics
Rats
Rats, Inbred F344
Substantia Nigra - enzymology
Tyrosine 3-Monooxygenase - metabolism
Abstract
BACKGROUND: Tyrosine hydroxylase (TH) regulates dopamine (DA) bioavailability. Its product, L-DOPA, is an established treatment for Parkinson's disease (PD), suggesting that TH regulation influences locomotion. Site-specific phosphorylation of TH at ser31 and ser40 regulates activity. No direct evidence shows that ser40 phosphorylation is the dominating mechanism of regulating TH activity in vivo, and physiologically-relevant stimuli increase L-DOPA biosynthesis independent of ser40 phosphorylation. Significant loss of locomotor activity occurs in aging as in PD, despite less loss of striatal DA or TH in aging compared to the loss associated with symptomatic PD. However, in the substantia nigra (SN), there is equivalent loss of DA or TH in aging and at the onset of PD symptoms. Growth factors increase locomotor activity in both PD and aging models and increase DA bioavailability and ser31 TH phosphorylation in SN, suggesting that ser31 TH phosphorylation status in the SN, not striatum, regulates DA bioavailability necessary for locomotor activity. METHODOLOGY AND PRINCIPAL FINDINGS: We longitudinally characterized locomotor activity in young and older Brown-Norway Fischer 344 F(1) hybrid rats (18 months apart in age) at two time periods, eight months apart. The aged group served as an intact and pharmacologically-naïve source of deficient locomotor activity. Following locomotor testing, we analyzed DA tissue content, TH protein, and TH phosphorylation in striatum, SN, nucleus accumbens, and VTA. Levels of TH protein combined with ser31 phosphorylation alone reflected inherent differences in DA levels among the four regions. Measures strictly pertaining to locomotor activity initiation significantly correlated to DA content only in the SN. Nigral TH protein and ser31 phosphorylation together significantly correlated to test subject's maximum movement number, horizontal activity, and duration. CONCLUSIONS/SIGNIFICANCE: Together, these results show ser31 TH phosphorylation regulates DA bioavailability in intact neuropil, its status in the SN may regulate locomotor activity generation, and it may represent an accurate target for treating locomotor deficiency. They also show that neurotransmitter regulation in cell body regions can mediate behavioral outcomes and that ser31 TH phosphorylation plays a role in behaviors dependent upon catecholamines, such as dopamine.
PubMed ID
20037632 View in PubMed
Less detail

Application of ALOGPS 2.1 to predict log D distribution coefficient for Pfizer proprietary compounds.

https://arctichealth.org/en/permalink/ahliterature9356
Source
J Med Chem. 2004 Nov 4;47(23):5601-4
Publication Type
Article
Date
Nov-4-2004
Author
Igor V Tetko
Gennadiy I Poda
Author Affiliation
Biomedical Department, Institute of Bioorganic and Petroleum Chemistry, Ukrainian Academy of Sciences, Murmanskaya 1, Kyiv, 02094, Ukraine. itetko@vcclab.org
Source
J Med Chem. 2004 Nov 4;47(23):5601-4
Date
Nov-4-2004
Language
English
Publication Type
Article
Keywords
1-Octanol
Administration, Oral
Biological Availability
Chemistry, Pharmaceutical
Databases, Factual
Drug Design
Drug Industry
Hydrogen-Ion Concentration
Neural Networks (Computer)
Pharmaceutical Preparations - chemistry - metabolism
Private Sector
Quantitative Structure-Activity Relationship
Research Support, Non-U.S. Gov't
Software
Solubility
Water
Abstract
Evaluation of the ALOGPS, ACD Labs LogD, and PALLAS PrologD suites to calculate the log D distribution coefficient resulted in high root-mean-squared error (RMSE) of 1.0-1.5 log for two in-house Pfizer's log D data sets of 17,861 and 640 compounds. Inaccuracy in log P prediction was the limiting factor for the overall log D estimation by these algorithms. The self-learning feature of the ALOGPS (LIBRARY mode) remarkably improved the accuracy in log D prediction, and an rmse of 0.64-0.65 was calculated for both data sets.
PubMed ID
15509156 View in PubMed
Less detail

ARC15105 is a potent antagonist of von Willebrand factor mediated platelet activation and adhesion.

https://arctichealth.org/en/permalink/ahliterature127558
Source
Arterioscler Thromb Vasc Biol. 2012 Apr;32(4):902-9
Publication Type
Article
Date
Apr-2012
Author
Jolanta M Siller-Matula
Yahye Merhi
Jean-François Tanguay
Daniel Duerschmied
Denisa D Wagner
Kathleen E McGinness
P Shannon Pendergrast
Jou-Ku Chung
Xianbin Tian
Robert G Schaub
Bernd Jilma
Author Affiliation
Department of Cardiology, Medical University of Vienna, Austria.
Source
Arterioscler Thromb Vasc Biol. 2012 Apr;32(4):902-9
Date
Apr-2012
Language
English
Publication Type
Article
Keywords
Aged
Animals
Aptamers, Nucleotide - administration & dosage - pharmacokinetics - therapeutic use
Aptamers, Peptide - administration & dosage - pharmacokinetics - pharmacology
Austria
Biological Availability
Blood Platelets - drug effects - metabolism
Boston
Case-Control Studies
Collagen - metabolism
Cross-Sectional Studies
Dose-Response Relationship, Drug
Drug Stability
Female
Half-Life
Humans
Injections, Intravenous
Injections, Subcutaneous
Macaca fascicularis
Male
Middle Aged
Myocardial Infarction - blood
Platelet Activation - drug effects
Platelet Adhesiveness - drug effects
Platelet Aggregation Inhibitors - administration & dosage - pharmacokinetics - pharmacology
Platelet Function Tests
Protein Binding
Quebec
Rats
Swine
von Willebrand Factor - antagonists & inhibitors - metabolism
Abstract
We investigated the stability, pharmacokinetic, and pharmacodynamic profile of the 2(nd) generation anti-von Willeband factor aptamer ARC15105.
Platelet plug formation was measured by collagen/adenosine diphosphate-induced closure time with the platelet function analyzer-100 and platelet aggregation by multiple electrode aggregometry. Platelet adhesion was measured on denuded porcine aortas and in a flow chamber. Aptamer stability was assessed by incubation in nuclease rich human, monkey, and rat serum for up to 72 hours. Pharmacokinetic and pharmacodynamic profiles were tested in cynomolgus monkeys after IV and SC administration. The median IC(100) and IC(50) to prolong collagen/adenosine diphosphate-induced closure timewere 27 nmol/L and 12 nmol/L, respectively. ARC15105 (1.3 µmol/L) completely inhibited ristocetin-induced platelet aggregation in whole blood (P90% on denuded porcine aortas (P90% (P90% in blood samples taken 300 hours after a 20 mg/kg IV or SC dose in monkeys.
The potency, pharmacokinetic profile, and SC bioavailability of ARC15105 support its clinical investigation for chronic inhibition of von Willeband factor -mediated platelet activation.
PubMed ID
22282355 View in PubMed
Less detail

116 records – page 1 of 12.