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US Army basic combat training alters the relationship between body mass index and per cent body fat. BMJ Mil Health 2023; 169:340-345. [PMID: 34413114 PMCID: PMC10423487 DOI: 10.1136/bmjmilitary-2021-001936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 08/03/2021] [Indexed: 11/04/2022]
Abstract
INTRODUCTION/BACKGROUND As a proxy for adiposity, body mass index (BMI) provides a practical public health metric to counter obesity-related disease trends. On an individual basis, BMI cannot distinguish fat and lean components of body composition. Further, the relationship between BMI and body composition may be altered in response to physical training. We investigated this dynamic relationship by examining the effect of US Army basic combat training (BCT) on the association between BMI and per cent body fat (%BF). METHODS BMI and %BF were measured at the beginning (week 1) and end (week 9) of BCT in female (n=504) and male (n=965) trainees. Height and weight were obtained for BMI, and body composition was obtained by dual X-ray absorptiometry. Sensitivity and specificity of BMI-based classification were determined at two BMI thresholds (25 kg/m2 and 27.5 kg/m2). RESULTS A progressive age-related increase in fat-free mass index (FFMI) was observed, with an inflection point at age 21 years. In soldiers aged 21+, BMI of 25.0 kg/m2 predicted 33% and 29% BF in women and 23% and 20% BF in men and BMI of 27.5 kg/m2 predicted 35% and 31% BF in women and 26% and 22% BF in men, at the start and end of BCT, respectively. Sensitivity and specificity of BMI-based classification of %BF were poor. Soldiers below BMI of 20 kg/m2 had normal instead of markedly reduced %BF, reflecting especially low FFMI. CONCLUSIONS BCT alters the BMI-%BF relationship, with lower %BF at a given BMI by the end of BCT compared with the beginning, highlighting the unreliability of BMI to try to estimate body composition. The specific BMI threshold of 25.0 kg/m2, defined as 'overweight', is an out-of-date metric for health and performance outcomes. To the extent that %BF reflects physical readiness, these data provide evidence of a fit and capable military force at BMI greater than 25.0 kg/m2.
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Making use of apex predator sample collections: an integrated workflow for quality assured sample processing, analysis and digital sample freezing of archived samples. CHEMOSPHERE 2022; 309:136603. [PMID: 36174727 DOI: 10.1016/j.chemosphere.2022.136603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 09/21/2022] [Accepted: 09/22/2022] [Indexed: 06/16/2023]
Abstract
Using monitoring data from apex predators for chemicals risk assessment can provide important information on bioaccumulating as well as biomagnifying chemicals in food webs. A survey among European institutions involved in chemical risk assessment on their experiences with apex predator data in chemical risk assessment revealed great interest in using such data. However, the respondents indicated that constraints were related to expected high costs, lack of standardisation and harmonised quality criteria for exposure assessment, data access, and regulatory acceptance/application. During the Life APEX project, we demonstrated that European sample collections (i.e. environmental specimen banks (ESBs), research collection (RCs), natural history museums (NHMs)) archive a large variety of biological samples that can be readily used for chemical analysis once appropriate quality assurance/control (QA/QC) measures have been developed and implemented. We therefore issued a second survey on sampling, processing and archiving procedures in European sample collections to derive key quality QA/QC criteria for chemical analysis. The survey revealed great differences in QA/QC measures between ESBs, NHMs and RCs. Whereas basic information such as sampling location, date and biometric data were mostly available across institutions, protocols to accompany the sampling strategy with respect to chemical analysis were only available for ESBs. For RCs, the applied QA/QC measures vary with the respective research question, whereas NHMs are generally less aware of e.g. chemical cross-contamination issues. Based on the survey we derived key indicators for assessing the quality of biota samples that can be easily implemented in online databases. Furthermore, we provide a QA/QC workflow not only for sampling and processing but also for the chemical analysis of biota samples. We focussed on comprehensive analytical techniques such as non-target screening and provided insights into subsequent storage of high-resolution chromatograms in online databases (i.e. digital sample freezing platform) to ultimately support chemicals risk assessment.
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Long-term trends of second generation anticoagulant rodenticides (SGARs) show widespread contamination of a bird-eating predator, the Eurasian Sparrowhawk (Accipiter nisus) in Britain. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 314:120269. [PMID: 36162558 DOI: 10.1016/j.envpol.2022.120269] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 09/20/2022] [Accepted: 09/21/2022] [Indexed: 06/16/2023]
Abstract
Second generation anticoagulant rodenticides (SGARs) are widely used to control rodents around the world. However, contamination by SGARs is detectable in many non-target species, particularly carnivorous mammals or birds-of-prey that hunt or scavenge on poisoned rodents. The SGAR trophic transfer pathway via rodents and their predators/scavengers appears widespread, but little is known of other pathways of SGAR contamination in non-target wildlife. This is despite the detection of SGARs in predators that do not eat rodents, such as specialist bird-eating hawks. We used a Bayesian modelling framework to examine the extent and spatio-temporal trends of SGAR contamination in the livers of 259 Eurasian Sparrowhawks, a specialist bird-eating raptor, in regions of Britain during 1995-2015. SGARs, predominantly difenacoum, were detected in 81% of birds, with highest concentrations in males and adults. SGAR concentrations in birds were lowest in Scotland and higher or increasing in other regions of Britain, which had a greater arable or urban land cover where SGARs may be widely deployed for rodent control. However, there was no overall trend for Britain, and 97% of SGAR residues in Eurasian Sparrowhawks were below 100 ng/g (wet weight), which is a potential threshold for lethal effects. The results have potential implications for the population decline of Eurasian Sparrowhawks in Britain. Fundamentally, the results indicate an extensive and persistent contamination of the avian trophic transfer pathway on a national scale, where bird-eating raptors and, by extension, their prey appear to be widely exposed to SGARs. Consequently, these findings have implications for wildlife contamination worldwide, wherever these common rodenticides are deployed, as widespread exposure of non-target species can apparently occur via multiple trophic transfer pathways involving birds as well as rodents.
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Assessment of contaminants of emerging concern in European apex predators and their prey by LC-QToF MS wide-scope target analysis. ENVIRONMENT INTERNATIONAL 2022; 170:107623. [PMID: 36379200 DOI: 10.1016/j.envint.2022.107623] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 10/23/2022] [Accepted: 11/07/2022] [Indexed: 06/16/2023]
Abstract
Apex predators are good indicators of environmental pollution since they are relatively long-lived and their high trophic position and spatiotemporal exposure to chemicals provides insights into the persistent, bioaccumulative and toxic (PBT) properties of chemicals. Although monitoring data from apex predators can considerably support chemicals' management, there is a lack of pan-European studies, and longer-term monitoring of chemicals in organisms from higher trophic levels. The present study investigated the occurrence of contaminants of emerging concern (CECs) in 67 freshwater, marine and terrestrial apex predators and in freshwater and marine prey, gathered from four European countries. Generic sample preparation protocols for the extraction of CECs with a broad range of physicochemical properties and the purification of the extracts were used. The analysis was performed utilizing liquid (LC) chromatography coupled to high resolution mass spectrometry (HRMS), while the acquired chromatograms were screened for the presence of more than 2,200 CECs through wide-scope target analysis. In total, 145 CECs were determined in the apex predator and their prey samples belonging in different categories, such as pharmaceuticals, plant protection products, per- and polyfluoroalkyl substances, their metabolites and transformation products. Higher concentration levels were measured in predators compared to prey, suggesting that biomagnification of chemicals through the food chain occurs. The compounds were prioritized for further regulatory risk assessment based on their frequency of detection and their concentration levels. The majority of the prioritized CECs were lipophilic, although the presence of more polar contaminants should not be neglected. This indicates that holistic analytical approaches are required to fully characterize the chemical universe of biota samples. Therefore, the present survey is an attempt to systematically investigate the presence of thousands of chemicals at a European level, aiming to use these data for better chemicals management and contribute to EU Zero Pollution Ambition.
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A review of constraints and solutions for collecting raptor samples and contextual data for a European Raptor Biomonitoring Facility. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 793:148599. [PMID: 34328978 DOI: 10.1016/j.scitotenv.2021.148599] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 06/14/2021] [Accepted: 06/18/2021] [Indexed: 06/13/2023]
Abstract
The COST Action 'European Raptor Biomonitoring Facility' (ERBFacility) aims to develop pan-European raptor biomonitoring in support of better chemicals management in Europe, using raptors as sentinel species. This presents a significant challenge involving a range of constraints that must be identified and addressed. The aims of this study were to: (1) carry out a comprehensive review of the constraints that may limit the gathering in the field of raptor samples and contextual data, and assess their relative importance across Europe; and (2) identify and discuss possible solutions to the key constraints that were identified. We applied a participatory approach to identify constraints and to discuss feasible solutions. Thirty-one constraints were identified, which were divided into four categories: legal, methodological, spatial coverage, and skills constraints. To assess the importance of the constraints and their possible solutions, we collected information through scientific workshops and by distributing a questionnaire to stakeholders in all the countries involved in ERBFacility. We obtained 74 answers to the questionnaire, from 24 of the 39 COST participating countries. The most important constraints identified were related to the collection of complex contextual data about sources of contamination, and the low number of existing raptor population national/regional monitoring schemes and ecological studies that could provide raptor samples. Legal constraints, such as permits to allow the collection of invasive samples, and skills constraints, such as the lack of expertise to practice necropsies, were also highlighted. Here, we present solutions for all the constraints identified, thus suggesting the feasibility of establishing a long-term European Raptor Sampling Programme as a key element of the planned European Raptor Biomonitoring Facility.
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Decabromodiphenylether trends in the European environment: Bird eggs, sewage sludge and surficial sediments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 774:145174. [PMID: 33609829 DOI: 10.1016/j.scitotenv.2021.145174] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 01/06/2021] [Accepted: 01/11/2021] [Indexed: 06/12/2023]
Abstract
Concern on relatively high levels and the potential bioaccumulation of decabromodiphenylether (BDE209) has led to a European 8-year monitoring program on trends in BDE209 concentrations in birds, sewage sludge and sediments from seven countries. BDE209 was analysed in four environmental matrices: sparrowhawk eggs (UK), glaucous gull eggs (Bear Island, Norway), sewage sludge (UK, Ireland and the Netherlands) and sediment (France, Germany, the Netherlands, UK and Ireland). BDE209 was detected in most of the glaucous gull and sparrow hawk eggs but neither increasing nor decreasing trends in these BDE209 levels were observed. An indication for debromination of BDE209 in sparrowhawk eggs was found. BDE209 concentrations in sediments ranged from very low ng/g (88 ng/g on an organic carbon (OC) basis) concentrations, in the rivers Elbe, Ems, Seine and the Outer Humber, to high μg/g (120 μg/g OC), in the Western Scheldt, Liverpool Bay and River Mersey. Apart from decreasing values in the Western Scheldt sediment no further decreases in BDE209 concentrations were observed over time, neither in sediment nor in sewage sludge showing that the voluntary emissions control program of the bromine industry only had a local effect. In contrast to the sewage sludge samples from the Netherlands (mean 355 ng/g dry weight (dw) or 1026 ng/g OC), the BDE209 concentrations in the UK increased at all sites from 2006 to 2011 (8092 ng/g dw or 22,367 ng/g OC). The BDE209 levels in several UK sediments and sewage sludge were still very high at the end of the program in 2012, most likely caused by frequent use of BDE209 in the textile industry. This may be indicative of the persistence of BDE209 and the limited degradation into lower brominated congeners in sediment, although it cannot be excluded that ongoing BDE209 emissions have played a role as well.
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Annual abundance of common Kestrels (Falco tinnunculus) is negatively associated with second generation anticoagulant rodenticides. ECOTOXICOLOGY (LONDON, ENGLAND) 2021; 30:560-574. [PMID: 33770305 PMCID: PMC8060177 DOI: 10.1007/s10646-021-02374-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/19/2021] [Indexed: 05/15/2023]
Abstract
Rats and mice can damage food and agricultural products as well as transmit diseases, thereby requiring control of their numbers. Application of Second Generation Anticoagulant Rodenticides (SGARs) often reduces rodent numbers locally. However, predators eating rodents, including non-target species, that have consumed SGARs may be secondarily exposed and potentially lethally poisoned. Here we study whether SGARs may have contributed to the widespread population declines of a rodent-eating raptor, the Common Kestrel (Falco tinnunculus) in the UK. We show that 161 (66.8%) of the 241 Kestrels submitted for ecotoxicology tests between 1997 and 2012 had detectable levels of at least one SGAR in their livers. Adult Kestrels had significantly higher prevalence of SGARs than juveniles, suggesting accumulation of SGARs through time. The prevalence and concentrations of individual SGARs in Kestrels were significantly higher in England than in Scotland. SGAR prevalence in Kestrels were positively associated with some land cover types, primarily arable cereals and broad-leaved woodland, and negatively associated with mainly mean elevation, probably reflecting variation in SGAR usage across land cover types. By using volunteer-collected data on national Kestrel abundance 1997-2012, we show that there is a negative correlation between the Kestrel population index in a specific year and the concentration of bromadialone as well as the total SGAR concentration in the same year. Although correlative, this is the first study to provide evidence for a potential population-limiting effect of SGARs on a raptor.
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Contrasting long term temporal trends in perfluoroalkyl substances (PFAS) in eggs of the northern gannet (Morus bassanus) from two UK colonies. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 754:141900. [PMID: 32916484 DOI: 10.1016/j.scitotenv.2020.141900] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 07/31/2020] [Accepted: 08/21/2020] [Indexed: 05/26/2023]
Abstract
We compared long-term (1977 to 2014) trends in concentrations of PFAS in eggs of the marine sentinel species, the Northern gannet (Morus bassanus), from the Irish Sea (Ailsa Craig) and the North Sea (Bass Rock). Concentrations of eight perfluorinated carboxylic acids (PFCAs) and three perfluorinated sulfonates (PFSAs) were determined and we report the first dataset on PFAS in UK seabirds before and after the PFOS ban. There were no significant differences in ∑PFAS or ∑PFSAs between both colonies. The ∑PFSAs dominated the PFAS profile (>80%); PFOS accounted for the majority of the PFSAs (98-99%). In contrast, ∑PFCAs concentrations were slightly but significantly higher in eggs from Ailsa Craig than in those from Bass Rock. The most abundant PFCAs were perfluorotridecanoate (PFTriDA) and perfluoroundecanoate (PFUnA) which, together with PFOA, comprised around 90% of the ∑PFCAs. The ∑PFSAs and ∑PFCAs had very different temporal trends. ∑PFSAs concentrations in eggs from both colonies increased significantly in the earlier part of the study but later declined significantly, demonstrating the effectiveness of the phasing out of PFOS production in the 2000s. In contrast, ∑PFCAs concentrations in eggs were constant and low in the 1970s and 1980s, suggesting minimal environmental contamination, but residues subsequently increased significantly in both colonies until the end of the study. This increase appeared driven by rises in long chain compounds, namely the odd chain numbered PFTriDA and PFUnA. PFOA, had a very different temporal trend from the other dominant acids, with an earlier rise in concentrations followed by a decline in the last 15 years in Ailsa Craig; later temporal trends in Bass Rock eggs were unclear. Although eggs from both colonies contained relatively low concentrations of PFAS, the majority had PFOS residues that exceeded a suggested Predicted No Effect Concentration and ~ 10% of the eggs exceeded a suggested Lowest-Observable-Adverse-Effect.
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Concentration and origin of lead (Pb) in liver and bone of Eurasian buzzards (Buteo buteo) in the United Kingdom. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 267:115629. [PMID: 33254650 DOI: 10.1016/j.envpol.2020.115629] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 09/01/2020] [Accepted: 09/08/2020] [Indexed: 06/12/2023]
Abstract
Ingestion of lead (Pb) derived from ammunition used in the hunting of game animals is recognised to be a significant potential source of Pb exposure of wild birds, including birds of prey. However, there are only limited data for birds of prey in Europe regarding tissue concentrations and origins of Pb. Eurasian buzzards (Buteo buteo) found dead in the United Kingdom during an 11-year period were collected and the concentrations of Pb in the liver and femur were measured. Concentrations in the liver consistent with acute exposure to Pb were found in 2.7% of birds and concentration in the femur consistent with exposure to lethal levels were found in 4.0% of individuals. Pb concentration in the femur showed no evidence of consistent variation among or within years, but was greater for old than for young birds. The Pb concentration in the liver showed no effect of the birds' age, but varied markedly among years and showed a consistent tendency to increase substantially within years throughout the UK hunting season for gamebirds. The resemblance of the stable isotope composition of Pb from buzzard livers to that of Pb from the types of shotgun ammunition most widely-used in the UK increased markedly with increasing Pb concentration in the liver. Stable isotope results were consistent with 57% of the mass of Pb in livers of all of the buzzards sampled being derived from shotgun pellets, with this proportion being 89% for the birds with concentrations indicating acute exposure to Pb. Hence, most of the Pb acquired by Eurasian buzzards which have liver concentrations likely to be associated with lethal and sublethal effects is probably obtained when they prey upon or scavenge gamebirds and mammals shot using Pb shotgun pellets.
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Biological and anthropogenic predictors of metal concentration in the Eurasian otter, a sentinel of freshwater ecosystems. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 266:115280. [PMID: 32823066 DOI: 10.1016/j.envpol.2020.115280] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 07/17/2020] [Accepted: 07/21/2020] [Indexed: 06/11/2023]
Abstract
Toxic metals have been linked to a range of adverse health effects in freshwater organisms. However, for higher vertebrates, there is little understanding of the large-scale drivers of exposure. We quantified toxic metal/semi-metal concentrations in a sentinel freshwater top predator, the Eurasian otter (Lutra lutra), across England and Wales, and determined how this varied with key natural and anthropogenic factors. We related liver concentrations in 278 otters that died between 2006 and 2017 to habitat biogeochemistry, proximity to point source contamination and to biological characteristics (length, sex, condition). Evidence for any positive association with putative anthropogenic sources (mining, human population, known discharges) was weak or lacking in nearly all cases, with the exception of a positive association between lead and human population density. Despite concerns that burgeoning use of nanosilver in consumer products might increase silver concentrations in waste waters, there was no increase over time. Spatial variation in soil/sediment pH, precipitation, and soil calcium oxide are indicated as significant predictors of metal concentrations in otters (higher cadmium and silver in areas with lower pH and higher rainfall, and higher chromium and lead in areas of lower calcium oxide). Liver chromium and nickel concentrations declined significantly over time (Cr 0.030 ± 1.2 to 0.015 ± 1.3 μg/g dry weight, Ni 0.0038 ± 1.2 to 0.00068 ± 1.5 μg/g, between 2006-2009 and 2014-2017), but other metals showed no temporal change. Biotic associations were important, with age related accumulation indicated for mercury and cadmium (as well as interactions with body condition). Our results suggest that larger-scale geochemical and hydrological processes are important in determining metal exposure in otters, and we provide an indication of risk factors that may be of relevance for freshwater vertebrates in other countries with well-developed water pollution management.
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Key principles and operational practices for improved nanotechnology environmental exposure assessment. NATURE NANOTECHNOLOGY 2020; 15:731-742. [PMID: 32807878 DOI: 10.1038/s41565-020-0742-1] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 06/23/2020] [Indexed: 06/11/2023]
Abstract
Nanotechnology is identified as a key enabling technology due to its potential to contribute to economic growth and societal well-being across industrial sectors. Sustainable nanotechnology requires a scientifically based and proportionate risk governance structure to support innovation, including a robust framework for environmental risk assessment (ERA) that ideally builds on methods established for conventional chemicals to ensure alignment and avoid duplication. Exposure assessment developed as a tiered approach is equally beneficial to nano-specific ERA as for other classes of chemicals. Here we present the developing knowledge, practical considerations and key principles need to support exposure assessment for engineered nanomaterials for regulatory and research applications.
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Stem cell intervention ameliorates epigallocatechin-3-gallate/lipopolysaccharide-induced hepatotoxicity in mice. Hum Exp Toxicol 2015; 34:1180-94. [PMID: 25701483 DOI: 10.1177/0960327115572707] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Stem cells are identified as a novel cell therapy for regenerative medicine because of their ability to differentiate into many functional cell types. We have shown earlier a new model of hepatotoxicity in mice by administering (1500 mg/kg) epigallocatechin-3-gallate (EGCG) intragastric (IG) for 5 days after a single intraperitoneal dose (6 mg/kg) of lipopolysaccharide (LPS). In this study, we aimed to study the effect of intrahepatic (IH) injection of mouse embryonic stem cells (MESCs) on the hepatotoxicity induced by EGCG/LPS in mice. Mice were administered EGCG/LPS and rested for 3 days. MESCs were obtained from American Type Culture Collection and cultured in vitro for 4 days. Stem cells were injected IH. Seven days later, a single dose of LPS (6 mg/kg) followed by daily doses of IG administration of EGCG were re-administered for 5 days. At the end of the experiment, blood samples were collected for analysis of biochemical parameters associated with liver. Results showed that the group of mice that were administered MESCs prior to EGCG/LPS showed lower levels of alanine amino transferase, alkaline phosphatase, and bilirubin, higher albumin/globulin ratio, and less remarkable histopathological lesions. Also, that group of mice showed less expression of oxidative stress biomarkers (oxidized low-density lipoprotein Ox.LDL and chemokine CXCL16), less expression of nuclear protein receptors (retinoic acid receptor and retinoid X receptor), and less expression of inflammatory biomarkers (tumor necrosis factor α and transforming growth factor β1) compared with other groups of mice that were not given MESCs. In conclusion, MESCs can ameliorate EGCG/LPS-induced hepatotoxicity in mice.
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How much do PCB toxic equivalents account for PHAH toxicity in predatory birds? ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2014; 193:240-246. [PMID: 25062280 DOI: 10.1016/j.envpol.2014.07.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 06/30/2014] [Accepted: 07/01/2014] [Indexed: 06/03/2023]
Abstract
Various diffuse polyhalogenated aromatic hydrocarbons (PHAHs) exert common toxicity through the aryl hydrocarbon receptor (AhR). Apex predators spatially and temporally integrate diffuse contamination and simultaneous exposure can cause additive toxicity. We investigated the extent to which PCBs, still amongst the most prevalent PHAHs accumulated by predators, accounted for total PHAH toxicity in raptors and fish eating birds from Britain. We analysed egg or liver extracts from six species and compared chemically determined ΣPCB-TEQs concentrations with total AhR-mediated toxicity determined using the chemical-activated luciferase gene expression bioassay (CALUX-TEQ). Dioxin-like PCB profiles in eggs and livers were dominated by congeners 118, 105 and 167. ΣPCB-TEQ and CALUX-TEQ concentrations were positively associated but not in a 1:1 relationship. ΣPCB-TEQ were broadly similar to CALUX-TEQ concentrations in eggs and livers with CALUX-TEQ concentrations >50-80 and 160-320 pg g(-1) lipid respectively, but were lower than CALUX-TEQ concentrations in less contaminated samples.
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Transfer parameters for ICRP reference animals and plants collected from a forest ecosystem. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2014; 53:125-149. [PMID: 24173444 DOI: 10.1007/s00411-013-0493-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Accepted: 09/15/2013] [Indexed: 06/02/2023]
Abstract
The International Commission on Radiological Protection (ICRP) have suggested the identification of a series of terrestrial, marine and freshwater sites from which samples of each Reference animal and plant (RAP) could be systematically collected and analysed. We describe the first such study in which six of the eight terrestrial RAPs, and associated soil samples, were collected from a site located in a managed coniferous forestry plantation in north-west England. Adult life stages of species representing six of the terrestrial RAPs (Wild grass, Pine tree, Deer, Rat, Earthworm and Bee) were sampled and analysed to determine concentrations of 60 elements and gamma-emitting radionuclides. The resultant data have been used to derive concentration ratios (CR(wo-soil)) relating element/radionuclide concentrations in the RAPs to those in soil. This paper presents the first-reported transfer parameters for a number of the RAP-element combinations. Where possible, the derived CR(wo-soil) values are compared with the ICRPs-recommended values and any appreciable differences discussed.
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Comparisons of metabolic and physiological changes in rats following short term oral dosing with pesticides commonly found in food. Food Chem Toxicol 2013; 59:438-45. [DOI: 10.1016/j.fct.2013.06.041] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Revised: 06/04/2013] [Accepted: 06/21/2013] [Indexed: 11/24/2022]
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Consumption of EGCG can Become Hepatotoxic Under Inflammatory Condition. PLANTA MEDICA 2013; 79. [DOI: 10.1055/s-0033-1336537] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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Anticancer activity of resveratrol analogs from Eugenia rigida DC. PLANTA MEDICA 2012; 78. [DOI: 10.1055/s-0032-1321001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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Decabromodiphenylether and hexabromocyclododecane in wild birds from the United Kingdom, Sweden and The Netherlands: Screening and time trends. CHEMOSPHERE 2011; 82:88-95. [PMID: 21044794 DOI: 10.1016/j.chemosphere.2010.09.073] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2010] [Revised: 09/24/2010] [Accepted: 09/27/2010] [Indexed: 05/30/2023]
Abstract
The brominated flame retardant decabromodiphenylether (DBDE) was analysed in wild birds to identify the most suitable species for monitoring time trends in DBDE contamination. This information was later used for the design of a 10-year trend study on DBDE in the European Union. DBDE was measured in muscle tissue, liver, and eggs from 10 terrestrial and four aquatic bird species. DBDE was detected in 47% of the terrestrial bird samples (nine species) and in 9% of the aquatic bird samples (six species). Peregrine falcon and sparrowhawk specimens were selected as most suitable species to determine temporal trends of DBDE. For sparrowhawks, no significant change in DBDE concentrations between 1973 and 2001 was found, although in later years more DBDE concentrations were above the detection limit. Peak DBDE levels measured in peregrines in 1995, were followed by a decline in concentrations until 2001. The same species were used for a trend study on hexabromocylcododecane (HBCD). Twenty-four percent of peregrine falcon eggs and 12% of sparrowhawk muscle samples demonstrated measurable HBCD residues. Three diastereomers of HBCD were analysed and the α-diastereomer was the predominant one in most samples. No clear time trends were observed for HBCD in either species. This study demonstrated that these DBDE and HBCD are bioavailable to birds of Northern Europe, although bioaccumulation seems to occur to a limited extent.
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Concentrations of polycyclic aromatic hydrocarbons (PAHs) in the eggs of predatory birds in Britain. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2009; 43:9010-9015. [PMID: 19943681 DOI: 10.1021/es901805e] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The eggs of gannets from two Scottish colonies (Ailsa Craig, Bass Rock) of golden eagles from the Hebrides and Highlands and of merlin eggs from the Scottish borders were analyzed for 52 PAHs, including 2-7 ring parent and alkylated PAHs. Phenanthrene was the most abundant PAH in gannet eggs from Ailsa Craig, and methylnaphthalenes predominated in the eggs from other locations and species. Most PAHs were detected in eggs but none were at likely embryotoxic concentrations. The sum concentrations for all the PAHs analyzed (3.1-5.7 ng g(-1) wet wt.) and for the U.S. EPA 16 priority PAHs (2.0-4.3 ng g(-1) wet wt.) did not differ significantly between species or locations. This uniform, low-level accumulation suggests background exposure to diffuse sources. PCA indicated that 3 ring parent and alkylated PAHs predominated in the eggs of merlins and gannets from Ailsa Craig and Hebridean golden eagles; other eggs had a more mixed profile. Source signature diagnostics largely suggested a petrogenic origin for the PAHs in the merlin eggs that we analyzed but otherwise gave equivocal results and further work is needed to determine which diagnostics can be successfully applied to PAHs in eggs.
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Do estuaries pose a toxic contamination risk for wading birds? ECOTOXICOLOGY (LONDON, ENGLAND) 2009; 18:906-917. [PMID: 19533343 DOI: 10.1007/s10646-009-0352-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2009] [Accepted: 06/01/2009] [Indexed: 05/27/2023]
Abstract
The impact of potentially toxic chemicals on wildlife is commonly assessed by comparing the intake of the contaminant with the "no observable effects level" (NOAEL) of intake. It is known, however, that there are considerable uncertainties inherent in this method. This study presents a Monte-Carlo based model to assess the degree of risk posed to birds (dunlin, Calidris alpina) from important estuarine habitats, and to show the limitations of such risk assessments, particularly with regard to data availability. The model was applied to predict the uptake of metals (Hg, Pb) in this shorebird species in Poole Harbour and the Severn Estuary/Bristol Channel, UK, two internationally important shorebird habitats. The results show that in both areas, Pb and Hg concentrations may pose an ecologically relevant toxic risk to wading birds. For Pb, uncertainty in NOAEL values dominates the overall uncertainty. Use of lethal toxicity data (LD50/100) was investigated as a method for assessing sub-lethal impacts from Hg. It was found that this method led to a significant under-estimate of the potential impact of Hg contamination, compared with direct estimation of NOAEL.
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Polybrominated diphenyl ether-associated alterations in cell biochemistry as determined by attenuated total reflection Fourier-transform infrared spectroscopy: a comparison with DNA-reactive and/or endocrine-disrupting agents. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2009; 43:3356-3364. [PMID: 19534158 DOI: 10.1021/es8036127] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Whether polybrominated diphenyl ethers (PBDEs) induce effects in target cells is increasingly important given that their environmental burdens are rising. Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy can be used to biochemically signature cells based on the notion that a detailed "biochemical-cell fingerprint" in the form of an infrared (IR) spectrum is derived. By employing subsequent computational approaches such as principal component analysis (PCA) and/or linear discriminant analysis (LDA), data reduction is achieved to allow for the identification of wavenumber-related biomarkers of effect Clustering of similar spectra (or scores) away from dissimilar ones highlights the variance responsible for discriminating classes. Discriminating biomarkers might include protein conformational changes, structural alterations to DNA/RNA, glycogen content, or protein phosphorylation. Employing this approach, we investigated in MCF-7 cells the dose-related effects of PBDEs (congeners 47, 153, 183, and 209), benzo[a]pyrene (B[a]P), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PHIP), 17beta-Oestradiol (E2), or lindane (gamma-hexachlorocyclohexane). Cultures concentrated in G0/G1- or S-phases were treated for 24 h. Following treatment MCF-7 cells were fixed and applied to IR reflective Low-E windows for interrogation using ATR-FTIR spectroscopy. At concentrations as low as 10(-12) M in culture, significant separation (P < or = 0.05) of PBDE-treated and vehicle control cell populations was noted. In some cases this was associated with alterations in lipid or the secondary structure of proteins; with DNA-reactive compounds (e.g., B[a]P), variance was primarily noted in the DNA/RNA region. This study points to a novel nondestructive approach capable of identifying contaminant effects at environmental concentrations in target cells.
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Long-term trends in mercury and PCB congener concentrations in gannet (Morus bassanus) eggs in Britain. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2009; 157:155-63. [PMID: 18799249 DOI: 10.1016/j.envpol.2008.07.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2008] [Revised: 07/03/2008] [Accepted: 07/17/2008] [Indexed: 05/24/2023]
Abstract
Gannet (Morus bassanus) eggs from Bass Rock (North Sea) and Ailsa Craig (eastern Atlantic) were monitored for PCB congeners (1990-2004) and total mercury (1974-2004). Congener profiles for both colonies were dominated by PCBs 153, 138, 180, 118 and 170. All declined in concentration at Ailsa Craig but some (153, 170, 180) remained stable or increased slightly at Bass Rock. Egg congener concentrations at Bass Rock were typically 10-fold higher than at Ailsa Craig by 2002, and Principal Component Analysis indicated that colony differences were driven by the dominant congeners. Egg mercury concentrations were significantly lower at Bass Rock than at Ailsa Craig and temporal trends differed, there being a significant decline at Ailsa Craig but a marginal increase at Bass Rock. Our results suggest there may be differences in contamination between the eastern Atlantic and North Sea and/or there are colony differences in prey selection and associated contaminant loads.
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Abstract
The Predatory Bird Monitoring Scheme (PBMS) is a long term (>40 y), UK-wide, exposure monitoring scheme that determines the concentration of selected pesticides and pollutants in the livers and eggs of predatory birds. This paper describes how the PBMS works, and in particular highlights some of the key scientific and policy drivers for monitoring contaminants in predatory birds and describes the specific aims, scope, and methods of the PBMS. We also present previously unpublished data that illustrates how the PBMS has been used to demonstrate the success of mitigation measures in reversing chemical-mediated impacts; identify and evaluate chemical threats to species of high conservation value; and finally to inform and refine monitoring methodologies. In addition, we discuss how such schemes can also address wider conservation needs.
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Second generation anticoagulant rodenticides in tawny owls (Strix aluco) from Great Britain. THE SCIENCE OF THE TOTAL ENVIRONMENT 2008; 392:93-8. [PMID: 18082246 DOI: 10.1016/j.scitotenv.2007.10.061] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2007] [Revised: 10/31/2007] [Accepted: 10/31/2007] [Indexed: 05/12/2023]
Abstract
Secondary exposure of vertebrate predators to second generation anticoagulant rodenticides (SGARs) is widespread in Britain. Tawny owl (Strix aluco) populations in the UK are thought to have declined since the 1970s, when SGARs were first introduced, and these compounds may have contributed to any decline in owl numbers. Our aims were to conduct the first systematic survey of SGAR exposure in tawny owls and ascertain whether there had been a change in the proportion of exposed birds that was concurrent with the decline in the population. Liver difenacoum, bromadiolone, flocoumafen and brodifacoum concentrations in British tawny owls from two periods (1990-1993 and 2003-2005) were quantified. In total, some 20% of birds contained detectable residues of one or more SGAR. The extent of exposure (% of birds exposed, magnitude of residues) to different SGARs did not change consistently between time periods. Of the raptors analysed to date in Britain, tawny owls had the lowest proportion of individuals that contained detectable liver residues and so appear to be the least vulnerable to exposure and/or assimilation of SGARs. We found no clear evidence to implicate SGARs as a major factor affecting tawny owl numbers in Britain between 1990 and 2005.
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Abstract
Understanding how novel antifungal compounds work in target cells is useful not only in facilitating the discovery of new drugs but also new tools that can be used for further exploration of the targeted biological pathways and their regulation. Various genomic and genetic technologies have been developed in the model yeast Saccharomyces cerevisiae, and have been successfully used to identify drug target pathways. This review discusses the methods developed for some of these technologies, and how they have been used to evaluate the cellular pathways affected by a variety of therapeutic drugs and inhibitors. The advantages and disadvantages of each method are considered, and new advances are highlighted where applicable. The investigation of the mechanism of action of new antifungal compounds will undoubtedly lead to the development of new antifungal therapies targeting new fungal pathways that are more specific and less toxic than currently available antifungal drugs.
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Cellular acidosis in rodents exposed to cadmium is caused by adaptation of the tissue rather than an early effect of toxicity. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2007; 2:316-21. [DOI: 10.1016/j.cbd.2007.06.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2007] [Revised: 06/15/2007] [Accepted: 06/15/2007] [Indexed: 10/23/2022]
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Heavy metal contamination in bats in Britain. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2007; 148:483-90. [PMID: 17257720 DOI: 10.1016/j.envpol.2006.12.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2006] [Revised: 12/01/2006] [Accepted: 12/05/2006] [Indexed: 05/04/2023]
Abstract
Toxic metals are bioaccumulated by insectivorous mammals but few studies (none from Britain) have quantified residues in bats. We measured renal mercury (Hg), lead (Pb) and cadmium (Cd) concentrations in bats from south-west England to determine how they varied with species, sex, age, and over time, and if they were likely to cause adverse effects. Residues were generally highest in whiskered bats (Myotis mystacinus). Compared with other species, pipistrelle (Pipistrellus spp) and Natterer's bats (Myotis nattereri) had significantly lower kidney Hg and Pb concentrations, respectively. Renal Hg increased over time in pipistrelles but the contributory sources are unknown. Kidney Pb did not decrease over time despite concurrent declines in atmospheric Pb. Overall, median renal metal concentrations were similar to those in bats from mainland Europe and 6- to 10-fold below those associated with clinical effect, although 5% of pipistrelles had kidney Pb residues diagnostic of acute lead poisoning.
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Lead contamination and associated disease in captive and reintroduced red kites Milvus milvus in England. THE SCIENCE OF THE TOTAL ENVIRONMENT 2007; 376:116-27. [PMID: 17307237 DOI: 10.1016/j.scitotenv.2007.01.062] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2006] [Revised: 12/20/2006] [Accepted: 01/05/2007] [Indexed: 05/14/2023]
Abstract
Since 1989, a red kite Milvus milvus reintroduction programme has been underway in the United Kingdom, with 4-6 week old nestlings brought into captivity and held for 6-8 weeks before reintroduction. As scavengers, red kites may consume unretrieved game, and ingest shot or lead (Pb) fragments in their prey's flesh. We evaluated exposure to Pb in captive and wild red kites by taking blood samples from 125 captive young red kites prior to release, through analysing 264 pellets (regurgitated by wild birds) collected from under a roost site, and analysing Pb concentrations in livers and/or bones of 87 red kites found dead between 1995 and 2003. Lead isotope analyses of livers were also conducted in an effort to identify Pb exposure routes. Forty-six (36.8%) kites sampled prior to release had elevated blood Pb concentrations (201-3340 microg l(-1)). The source of this Pb was probably small fragments of lead ammunition in the carcasses of birds or mammals either fed to the nestlings by their parents or, more likely, subsequently whilst in captivity. Once released, kites were also exposed to lead shot in their food, and a minimum of 1.5-2.3% of regurgitated pellets contained Pb gunshot. Seven of 44 red kites found dead or that were captured sick and died within a few days had elevated (>6 mg kg(-1) dry weight [d.w.]) liver Pb concentrations, and six of these (14%) had concentrations of >15 mg kg(-1) d.w., compatible with fatal Pb poisoning. Post-mortem analyses indicated that two of these birds had died of other causes (poisoning by rodenticide and a banned agricultural pesticide); the remaining four (9%) probably died of Pb poisoning. Bone samples from 86 red kites showed a skewed distribution of Pb concentration, and 18 samples (21%) had Pb concentrations >20 mg kg(-1) d.w., indicating elevated exposure to Pb at some stage in the birds' life. Lead isotopic signatures (Pb (208/206); Pb (206/207)) in liver samples of the majority of kites were compatible with those found in lead shot extracted from regurgitated pellets. Lead isotope ratios found in the livers of kites with very low Pb concentrations were distinct from UK petrol Pb isotopic signatures, indicating that birds were exposed to little residual petrol Pb. We conclude that the primary source of Pb to which red kites are exposed is lead ammunition (shotgun pellets or rifle bullets), or fragments thereof, in their food sources; in some cases exposure appears sufficient to be fatal. We make recommendations to reduce Pb poisoning in both captive and wild red kites and other scavenging species.
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Bone density and breaking strength in UK raptors exposed to second generation anticoagulant rodenticides. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2007; 78:249-51. [PMID: 17453124 DOI: 10.1007/s00128-007-9122-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2006] [Accepted: 03/16/2007] [Indexed: 05/15/2023]
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Abstract
Bruceantin (1), a classical quassinoid with the highest reported antimalarial activity among the quassinoids examined thus far, was selected as a natural product lead for the design of a series of A/B-ring analogs. A viable strategy for the synthesis of the series was developed. The functionalized A-ring and the C-15 ester moiety in bruceantin are incorporated in all designed compounds. The preliminary bioassay results will be discussed in detail.
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Abstract
Quassinoids are highly oxygenated triterpenes, which were isolated as bitter principles from the plants of Simaroubaceae family. Their synthesis has attracted much attention because of the wide spectrum of their biological properties. The most prevalent quassinoids have C-20 picrasane skeleton, some known as bruceolides as they were isolated from the genus Brucea, which showed marked antileukemic and antimalarial activities.
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Modeling cadmium dynamics in the guts and tissues of small mammals: dose implications for predators. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2002; 21:2493-2499. [PMID: 12389931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Predators that consume contaminated small-mammal prey are exposed to pollutants present in both the prey tissues and the prey gut. However, the contribution of the prey gut and its contents to the contaminant intake of the predator is often ignored. This study developed a two-compartment model of the dynamics of Cd in a model prey species, the wood mouse (Apodemus sylvaticus). The results from the Cd dynamics model were used to calibrate a revised predator dose estimation methodology that accounted for contaminant uptake by a predator from both prey tissues and guts. The dose to the predator predicted by the revised methodology was compared to that predicted by conventional dose calculations, which account for contaminants in prey tissues only. The conventional approach underestimated Cd dose to a model predator by a factor of 1.2- to 10-fold, depending on prey age and predator behavior. Thus, accounting for the contaminant burden in the prey gut as well as in the tissues can markedly increase dose estimates to predators, and this is likely to be true for most low-bioavailability pollutants. This study has major implications for ecological risk assessment involving food chain transfer of low-bioavailability xenobiotics to predators.
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Solution-phase parallel synthesis of an isoflavone library for the discovery of novel antigiardial agents. Comb Chem High Throughput Screen 2002; 5:481-7. [PMID: 12470277 DOI: 10.2174/1386207023330138] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Combinatorial chemistry has become a dramatically useful tool for the development of new medicinal agents. In the search to discover a novel and effective lead for the treatment of giardiasis, solution-phase synthesis of a library of isoflavone derivatives has been accomplished. Of the products screened, several compounds such as P(A1,B1) and P(A1,B11) exhibited potent antigiardial activity. The details of synthesis, in vitro antigiardial assay, and preliminary structure-activity relationships of these compounds are described.
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Biologically active steroidal glycosides from Tribulus terrestris. DIE PHARMAZIE 2002; 57:491-3. [PMID: 12168535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
The steroidal saponin constituents obtained from Tribulus terrestris were tested for their antimicrobial and cytotoxic effects. The spirostanol-based steroidal saponins 1-3 exhibited remarkable activity against fungal organisms (Candida albicans and Cryptococcus neoformans) and cancer cell lines [human malignant melanoma (SK-MEL), human oral epidermoid carcinoma (KB), human breast ductal carcinoma (BT-549), and human ovary carcinoma (SK-OV-3)], while none of the compounds possessing the furostanol framework 4-7 showed activity. The most active spirostanol glycoside, compound 3 exhibited a broad range of anticancer activity against cell lines, SK-MEL, KB, BT-549 and SK-OV-3 at IC50s of 6.0, 7.0, 6.0 and 8.2 micrograms/ml, respectively, while compounds 1 and 2 showed selective cytotoxicity against SK-MEL at 6.7 and 9.1 micrograms/ml, respectively. The minimum inhibitory concentrations (MIC) in antifungal bioassay for compounds 1-3 varied from 1.5 to 6.2 micrograms/ml, which prompted to conclude certain structural features are required for these bioactivities.
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Abstract
There is no legislation that restricts the practice of CAM in the UK apart from the practice of chiropractic and osteopathy and limits on advertising the treatments of certain conditions such as cancer and tuberculosis. The UK government has increasingly recognised the need for comprehensive regulation of CAM, though it abandoned its original plan for a single overarching regulatory body. Initiatives to examine and hasten the process of regulation have included setting up a central, well-recognised charitable body to facilitate progress for individual professions, and an authoritative survey of the existing professional organisations. One pathway open to individual professions is statutory self-regulation, which requires a single governing body, a systematic corpus of knowledge, recognised training courses and demonstrated efficacy. The other pathway is voluntary self-regulation. Chiropractic and osteopathy have adopted statutory self-regulation, though this has proved expensive for individual members of these professions. A recent House of Lords report on CAM has recommended that the herbal medicine and acupuncture professions should also develop a system of statutory regulation. Other professions, such as aromatherapy, are in the process of establishing single professional bodies as a first step towards self-regulation. Among the issues that remain to be resolved is the relationship between the CAM professions and statutory registered practitioners who also practise CAM.
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The importance of the gut and its contents in prey as a source of cadmium to predators. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2002; 21:76-80. [PMID: 11804064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Many mammalian and avian predators consume the whole carcass of their small mammal prey. Thus, the contaminant load of the gut and its contents may be of toxicological significance, but pollutant loads in the gut of prey species are often not measured and their role in food-chain transfer of contaminants is largely unquantified. We investigated the importance of the gut and its contents in prey as a source of cadmium (Cd) to predators by measuring the Cd concentrations in the guts (including contents), in various body tissues, and in the intact bodies of wood mice (Apodemus sylvaticus). The mice had been fed for up to 365 d on either control, a medium-Cd (MCd) diet, or a high-Cd (HCd) diet that had nominal Cd concentrations of 0, 8, and 40 g/g wet weight, respectively. In wood mice fed contaminated diets, Cd was progressively bioaccumulated in all the body tissues that were analyzed. The gut (and contents) and the liver and kidneys (the critical organs) contained most of the accumulated Cd and were the only significant contributors to the total body burden (TBB). The contribution of the gut (and contents) to the TBB was greater in mice fed MCd diet than in those given HCd feed but declined with age (equivalent to exposure duration) in both groups as Cd in the critical organs increasingly became the most important source of TBB Cd. However, the gut and its contents contributed between 50 and 100% of the Cd TBB in mice fed for up to six months on MCd diet; this was the diet that most closely mimicked the estimated average Cd intake of wood mice on contaminated sites. The results of this study highlight the importance of including measures of Cd load in the gut when modeling food-chain transfer from small mammals to their predators.
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N-(2-hydroxypropyl)methacrylamide (HPMA) copolymers for targeted delivery of 8-aminoquinoline antileishmanial drugs. J Control Release 2001; 77:233-43. [PMID: 11733091 DOI: 10.1016/s0168-3659(01)00514-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A challenge to successful chemotherapy of visceral leishmaniasis is the dose-limiting toxicity of antileishmanial agents. One approach to increase the efficacy and reduce the toxicity of these agents is to direct the drug to the phagolysosomes of the reticuloendothelial system (RES) where the leishmanial parasites reside. In this work a series of N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer-antileishmanial drug conjugates containing lysosomally degradable side chains and with or without sugar targeting moieties were synthesized, characterized and investigated for their in vivo efficacy in mice infected with Leishmania. An 8-aminoquinoline analog, namely 8-[(4-amino-1-methylbutyl)amino]-5-[3,4-dichlorophenoxy]-6-methoxy-4-methylquinoline (NPC1161) was used as a model antileishmanial agent. At 5 mg/kg body weight drug equivalent dose, all HPMA copolymer-drug conjugates which contained lysosomally degradable side chains showed significant in vivo antileishmanial activity (>99% inhibition), comparable to the activity of the free drug. At 2 mg dose, the same conjugates were significantly more effective (84-90% inhibition) than the free drug (67% inhibition). These results indicate the potential of lysosomotropic HPMA copolymers for the targeted delivery of antileishmanial compounds in the treatment of visceral leishmaniasis.
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Abstract
The indolopyridoquinazoline alkaloid, 3-hydoxyrutaecarpine, was isolated from Leptothyrsa sprucei, along with 8-methoxypsoralen, 5-methoxypsoralen, imperatorin, isoimperatorin, kaempferol 3-O-alpha-L-rhamnopyranoside, clematine and cnidioside B. The usefulness of the gradient 1H-15N HMBC NMR spectroscopy in the structure elucidation of 3-hydroxyrutaecarpine is noted.
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Abstract
A confounding problem with studying the effects of environmental exposure to contaminants in wild populations is that analytical techniques are invasive, particularly where the physiological effects of the toxin are assessed. In this study, a metabonomic approach to investigate the biochemical effects of chronic oral exposure to environmentally realistic doses of CdCl2 (low, 8 mg/kg; high, 40 mg/kg) is presented. 1H NMR spectra of urine from exposed animals were analyzed using pattern recognition methods to identify biomarkers for a 94 day exposure period. Creatinuria and both increased excretion and complexation of citrate was detected after 19 days of exposure in both exposure groups. This was accompanied by a decrease in plasma Ca2+/Mg2+ ratio in blood plasma after 94 days. Post mortem, magic angle spinning (MAS) 1H NMR spectroscopy was used alongside conventional analytical techniques to investigate intact tissue directly. According to atomic absorption spectroscopy, kidney tissue accumulated 26.8 +/- 2.5 microg of Cd2+/g dry wt (low) and 75.9 +/- 4.3 microg of Cd2+/g dry wt (high). Using high-resolution MAS 1H NMR spectroscopy altered lipid content was detected in kidneys from animals exposed to Cd2+. However, unlike acute exposure, no testicular damage was evident. This systemic approach to metabolism demonstrated the different physiological effects of chronic subacute compared with an acute exposure to Cd2+.
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Phenolic compounds from Miconia myriantha inhibiting Candida aspartic proteases. JOURNAL OF NATURAL PRODUCTS 2001; 64:1282-1285. [PMID: 11678651 DOI: 10.1021/np010172p] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Assay-guided fractionation of the ethanol extract of the twigs and leaves of Miconia myriantha yielded two new compounds, mattucinol-7-O-[4' ',6' '-O-(S)-hexahydroxydiphenoyl]-beta-D-glucopyranoside (1) and mattucinol-7-O-[4' ',6' '-di-O-galloyl]-beta-D-glucopyranoside (2), along with mattucinol-7-O-beta-D-glucopyranoside (3), ellagic acid (4), 3,3'-di-O-methyl ellagic acid-4-O-beta-D-xylopyranoside, and gallic acid. Complete (1)H and (13)C NMR assignments of compound 1, which possesses a hexahydroxydiphenoyl unit, were achieved using the HMBC technique optimized for small couplings to enhance the four-bond and two-bond H/C correlations. Compounds 1 and 4 showed inhibitory effects against Candida albicans secreted aspartic proteases, with IC(50) of 8.4 and 10.5 microM, respectively.
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A new naphthopyrone derivative from Cassia quinquangulata and structural revision of quinquangulin and its glycosides. JOURNAL OF NATURAL PRODUCTS 2001; 64:1153-1156. [PMID: 11575947 DOI: 10.1021/np010173h] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A novel naphthopyrone derivative, named quinquangulone (1), has been isolated from Cassia quinquangulata, along with the known compounds quinquangulin (2) and its two glycosides (3 and 4), rubrofusarin (5) and its two glycosides (6 and 7), nor-rubrofusarin (8) and its 6-O-glucoside (9), and three stilbenes (10-12). The structure of quinquangulone was established by spectral interpretation as 5,9-dihydroxy-8-methoxy-2,9-dimethyl-6-oxo-4H,6H,9H-naphtho-[2,3-b]pyran-4-one. Reinvestigation of the NMR spectra of quinquangulin led to revision of its structure as 5,6-dihydroxy-8-methoxy-2,9-dimethyl-4H-naphtho[2,3-b]pyran-4-one (2a). The structures of two quinguangulin glycosides, 3 and 4, were also revised accordingly. Compound 2a exhibited activity against Staphylococcus aureus and methicillin-resistant S. aureus (MIC, 3.125 and 6.25 microg/mL, respectively).
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Abstract
Four new alkaloids, nauclealines A (1) and B (2) and naucleosides A (3) and B (4), together with six known compounds, strictosamide (5), vincosamide (6), pumiloside (7), kelampayoside A, sitosterol, and sitosteryl beta-D-glucoside, were isolated from the bark of Nauclea orientalis. The structures of 1-4 were elucidated using 1D and 2D NMR spectral methods, including COSY, DEPT, HMQC, (13)C-(1)H HMBC, and (15)N-(1)H HMBC.
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Site-specific phosphorylation and point mutations of telokin modulate its Ca2+-desensitizing effect in smooth muscle. J Biol Chem 2001; 276:24519-24. [PMID: 11346659 DOI: 10.1074/jbc.m103560200] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Forskolin and 8-bromoguanosine 3'-5'-cyclic monophosphate (8-Br-cGMP) induce phosphorylation of Ser-13 of telokin and relaxation of smooth muscle at constant calcium. Comparison with the effect of wild type with aspartate (D; to mimic phosphorylation) and alanine (A; non-phosphorylatable) mutants of telokin showed that the S13D mutant was more effective than wild type in relaxing smooth muscle at constant calcium. The efficacy of the Ser-13A, S12A, and S12D mutants was not significantly different from that of wild-type telokin. The effect of neither S13D nor Ser-13A was affected by 8-Br-cGMP, whereas the effect of wild type, S12A, and S12D was enhanced by 8-Br-cGMP, indicating the specificity of Ser-13 charge modification. Mutation of Ser-19 (a mitogen-activated protein kinase site) showed the S19A to be more effective than, and S19D to be not different from, wild-type telokin. The effect of both mutants was slightly enhanced by 8-Br-cGMP. A truncated (residues 1-142) form lacking the acidic C terminus had the same relaxant effect as wild-type telokin, whereas the C-terminal peptide (residues 142-155) had no effect. We conclude that site-specific modification of the N terminus modulates the Ca2+ -desensitizing effect of telokin on force.
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Determination of heavy metals and pesticides in ginseng products. J AOAC Int 2001; 84:936-9. [PMID: 11417656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
Medicinal plants may carry residuals of environmentally persistent pesticides or assimilate heavy metals in varying degrees. Several factors may influence contaminant accumulation, including species, level and duration of contaminant exposure, and topography. As part of a program for assessment of the quality of herbal medicines, we have analyzed 21 over-the-counter ginseng (Panax ginseng) products in various dosage forms. Chromium, mercury, and arsenic were undetectable above their limits of detection in both liquid and solid samples; while cadmium, lead, and nickel were present in the majority of samples. The chlorinated pesticide levels varied widely. In most samples, the total concentration of pesticides was below 100 ppb; while in 5 samples the total concentration exceeded 100 ppb.
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Antimalarial, cytotoxic, and antifungal alkaloids from Duguetia hadrantha. JOURNAL OF NATURAL PRODUCTS 2001; 64:559-562. [PMID: 11374943 DOI: 10.1021/np000436s] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Bioassay-guided isolation of Duguetia hadrantha yielded two new 4,5-dioxo-1-azaaporphinoids, hadranthine A (1) and hadranthine B (2), together with the known alkaloids imbiline-1 (3), sampangine (4), and 3-methoxysampangine (5), whose structures were determined primarily from 2D-NMR 1H-13C HMBC, and 1H-15N HMBC experiments. This is the first report of the co-occurrence of the copyrine alkaloids 4 and 5, as well as the first report of either copyrine or imbiline type alkaloids from a Duguetia species. Compounds 1, 4, and 5 demonstrated in vitro antimalarial activity against Plasmodium falciparum (W-2 clone), while 2 was inactive. Instead, 2 showed in vitro cytotoxicity to selected human cancer cell lines (IC50 = 3-6 microg/mL against SK-MEL, KB, BT-549, and SK-OV-3), and 4 was also cytotoxic to human malignant melanoma (IC50 = 0.37 microg/mL). Sampangine (4) also inhibited cell aggregation with a MIC value of <0.15 microg/mL, while 3-methoxysampangine (5) was only weakly active.
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Abstract
Bioactivity-guided fractionation of an ethanolic extract of the leaves and twigs of Piper longicaudatum Trelease & Yunker (Piperaceae) resulted in the isolation of one new (1) and three known (2-4) dihydrochalcones. The known compounds are: 2',6'-dihydroxy-4'-methoxydihydrochalcone (2), 2',6',4-trihydroxy-4'-methoxydihydrochalcone (asebogenin) (3), and 2'-hydroxy-4'-methoxy-2'-[1-hydroxy-1-methylethyl]-2",3"-dihy- drofurano[4",5":5',6"]-3"-[2-hydroxy-5-methoxycarbonylphe- nyl]dihydrochalcone (piperaduncin B) (4). The new compound is 2'-hydroxy-4'-methoxy-2"-[2-hydroxy-5-methoxycarbonyl- phenyl]-furano[4",5":5',6']-dihydrochalcone (longicaudatin) (1). Compounds 1-4 were tested for antibacterial activity against S. aureus and methicillin-resistant S. aureus (MRSA); only compound 3 showed inhibitory activity (IC50 of 10 and 4.5 micrograms/ml, respectively).
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Abstract
Five prenylated flavonoids, including one new natural product, were isolated from an ethanol extract of the leaves of Maclura tinctoria (L.) Gaud. The new compound has been characterized as 2',4',4,2''-tetrahydroxy-3'-[3''-methylbut-3''-enyl]chalcone (1). The known compounds were identified as 2',4',4-trihydroxy-3'-[3''-methylbut-3''-enyl]chalcone (isobavachalcone) (2), 4,2'-dihydroxy-2''-[1-hydroxy-1-methylethyl]-2'',3''-dihydrofurano[4'',5'':3',4']chalcone (bakuchalcone) (3), 4,4',5''-trihydroxy-6'',6''-dimethyldihydropyrano[2'',3'':5',6'']chalcone (bavachromanol) (4), and 5,7,3',4'-tetrahydroxy-6,8-diprenylisoflavone (6,8-diprenylorobol) (5). All the isolated compounds were evaluated against the AIDS-related opportunistic fungal pathogens, Candida albicans and Cryptococcus neoformans. Compound 2 was active against both yeasts.
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A new dammarane-type triterpene glycoside from Polyscias fulva. JOURNAL OF NATURAL PRODUCTS 2001; 64:95-7. [PMID: 11170676 DOI: 10.1021/np0003589] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A new dammarane-type triterpene glycoside, polysciasoside A (1), and three known compounds have been isolated from the leaves of Polyscias fulva. The structure of the new compound was established as 12-oxo-3beta,16beta,20(S)-trihydroxydammar-24-ene-3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside.
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