The combination of hydrogen/deuterium(H/D)formaldehyde-based isotopic methyl labeling with solid-phase extraction and high-performance liquid chromatography–high resolution mass spectrometry(HPLC-HRMS)is a powerful a...The combination of hydrogen/deuterium(H/D)formaldehyde-based isotopic methyl labeling with solid-phase extraction and high-performance liquid chromatography–high resolution mass spectrometry(HPLC-HRMS)is a powerful analytical solution for nontargeted analysis of trace-level amino-containing chemicals in water samples.Given the huge amount of chemical information generated in HPLC-HRMS analysis,identifying all possible H/Dlabeled amino chemicals presents a significant challenge in data processing.To address this,we designed a streamlined data processing pipeline that can automatically extract H/D-labeled amino chemicals from the raw HPLC-HRMS data with high accuracy and efficiency.First,we developed a cross-correlation algorithm to correct the retention time shift resulting from deuterium isotopic effects,which enables reliable pairing of H-and D-labeled peaks.Second,we implemented several bioinformatic solutions to remove false chemical features generated by in-source fragmentation,salt adduction,and natural13C isotopes.Third,we used a data mining strategy to construct the AMINES library that consists of over 38,000 structure-disjointed primary and secondary amines to facilitate putative compound annotation.Finally,we integrated these modules into a freely available R program,HDPairFinder.R.The rationale of each module was justified and its performance tested using experimental H/D-labeled chemical standards and authentic water samples.We further demonstrated the application of HDPairFinder to effectively extract N-containing contaminants,thus enabling the monitoring of changes of primary and secondary N-compounds in authentic water samples.HDPairFinder is a reliable bioinformatic tool for rapid processing of H/D isotopic methyl labeling-based nontargeted analysis of water samples,and will facilitate a better understanding of N-containing chemical compounds in water.展开更多
A broad range of organic compounds are known to exist in drinking water sources and serve as precursors of disinfection byproducts（DBPs）.Epidemiological findings of an association of increased risk of bladder cancer...A broad range of organic compounds are known to exist in drinking water sources and serve as precursors of disinfection byproducts（DBPs）.Epidemiological findings of an association of increased risk of bladder cancer with the consumption of chlorinated water has resulted in health concerns about DBPs.Peptides are thought to be an important category of DBP precursors in water.However,little is known about the actual presence of peptides and their DBPs in drinking water because of their high sample complexity and low concentrations.To address this challenge and identify peptides and non-chlorinated/chlorinated peptide DBPs from large sets of organic compounds in water,we developed a novel high throughput analysis strategy,which integrated multiple solid phase extraction（SPE）,high performance liquid chromatography（HPLC）separation,and non-target identification using precursor ion exclusion（PIE）high resolution mass spectrometry（MS）.After MS analysis,structures of candidate compounds,particularly peptides,were obtained by searching against the Human Metabolome Database（HMDB）.Using this strategy,we successfully detected 625 peptides（out of 17,205 putative compounds）and 617 peptides（out of 13,297）respectively in source and finished water samples.The source and finished water samples had 501 peptides and amino acids in common.The remaining 116 peptides and amino acids were unique to the finished water.From a subset of 30 putative compounds for which standards were available,25 were confirmed using HPLC-MS analysis.By analyzing the peptides identified in source and finished water,we successfully confirmed three disinfection reaction pathways that convert peptides into toxic DBPs.展开更多
Intact pZ189 DNA was replicated in monkey kidney vero cells which had been pretreated with Nmethyl-N’-nitro-N-nitrosoguanidine (MNNG) . The mutants were selected in E. coli MBM7070 and the mutation frequencies involv...Intact pZ189 DNA was replicated in monkey kidney vero cells which had been pretreated with Nmethyl-N’-nitro-N-nitrosoguanidine (MNNG) . The mutants were selected in E. coli MBM7070 and the mutation frequencies involving mutants with unchanged electrophoretic mobilrty of their plasmid DNA were scored. When compared to the spontaneous mutation frequency. the mutation frequencies were increased by 5.8 and 2.9-fold in cells pretreated with 0. 2 and 2μmol/L MNNG, respectively. The supF genes of these mutants were sequenced. and it was found that the types of base substitution and the sites of frameshifts differed from findings in studies of spontaneous and targeted mutagenesis. The results suggest that nontargeted mutagenesis occurs in mammalian cells and may have a sequence specificity.展开更多
Among the expressed sequence tags (ESTs) which were isolated from genetically instable monkey kidney vero cells induced by N-methyI-N’-nitro-N-nitrosoguanidine (MNNG), a fragment 9 was isolated. When the expression o...Among the expressed sequence tags (ESTs) which were isolated from genetically instable monkey kidney vero cells induced by N-methyI-N’-nitro-N-nitrosoguanidine (MNNG), a fragment 9 was isolated. When the expression of fragment 9 was blocked through transcripting antisense RNA, MNNGinduced nontargeted mutation frequency enhanced significantly compared with control ( P 【 0.05). The result showed that the relevant gene of fragment 9 might participate in maintaining cellular genetic stability and be involved in inhibition of nontargeted mutagenesis.展开更多
The introduction of drug-eluting stents has significantly reduced the incidence of in-stent restenosis.Despite this,recurrent cardiovascular events related to untreated nontarget lesions(NTLs)are becoming more common ...The introduction of drug-eluting stents has significantly reduced the incidence of in-stent restenosis.Despite this,recurrent cardiovascular events related to untreated nontarget lesions(NTLs)are becoming more common and accounting for more than 50%of all recurrent cardiovascular events.In patients with dia-betes,factors such as prolonged disease duration,poor glycemic control,insulin use,and inadequate lipid management may exacerbate the progression of NTLs and adverse cardiovascular events.Additionally,glycemic fluctuations have been linked to an increased risk of future cardiovascular events in patients with early glucose metabolism abnormalities and acute hyperglycemia.In this review,we explored the clinical and plaque characteristics of patients with diabetes and early glucose metabolism disorders,the percutaneous coronary intervention strategies for NTLs,and their prognostic implications.Furthermore,we investigated the mechanistic links between adverse cardiovascular outcomes and elevated inflammation,oxidative stress,hypercoagulability,and endothelial dysfunction.展开更多
BACKGROUND The relationship between metabolic syndrome(MetS)and gastric cancer(GC),which is a common metabolic disease,has attracted much attention.However,the specific metabolic characteristics of MetS in elderly pat...BACKGROUND The relationship between metabolic syndrome(MetS)and gastric cancer(GC),which is a common metabolic disease,has attracted much attention.However,the specific metabolic characteristics of MetS in elderly patients with GC remain unclear.AIM To investigate the differentially abundant metabolites and metabolic pathways between preoperative frailty and MetS in elderly patients with GC based on nontargeted metabolomics techniques.METHODS In this study,125 patients with nonfrail nonmeal GC were selected as the control group,and 50 patients with GC in the frail group were selected as the frail group.Sixty-five patients with GC combined with MetS alone were included in the MetS group,and 50 patients with GC combined with MetS were included in the MetS group.Nontargeted metabolomics techniques were used to measure plasma metabolite levels by ultrahigh-performance liquid chromatography-mass spectrometry.Multivariate statistical analysis was performed by principal component analysis,orthogonal partial least squares,pattern recognition analysis,cluster analysis,and metabolic pathway annotation.RESULTS A total of 125 different metabolites,including amino acids,glycerophospholipids,sphingolipids,fatty acids,sugars,nucleosides and nucleotides,and acidic compounds,were identified via nontargeted metabolomics techniques.Compared with those in the control group,there were 41,32,and 52 different metabolites in the MetS group,the debilitated group,and the combined group,respectively.Lipid metabolites were significantly increased in the MetS group.In the weak group,amino acids and most glycerol phospholipid metabolites decreased significantly,and fatty acids and sphingosine increased significantly.The combined group was characterized by significantly increased levels of nucleotide metabolites and acidic compounds.The alanine,aspartic acid,and glutamate metabolic pathways were obviously enriched in the asthenic group,and the glycerol and phospholipid metabolic pathways were obviously enriched in the combined group.CONCLUSION Elderly GC patients with simple frailty,simple combined MetS,and frailty combined with MetS have different metabolic characteristics,among which amino acid and glycerophospholipid metabolite levels are significantly lower in frail elderly GC patients,and comprehensive supplementation of fat and protein should be considered.Many kinds of metabolites,such as amino acids,lipids,nucleotides,and acidic compounds,are abnormally abundant in patients with MetS combined with fthenia,which may be related to tumor-related metabolic disorders.展开更多
Disinfection byproducts(DBPs)represent a ubiquitous source of chemical exposure in disinfected water.While over 700 DBPs have been identified,the drivers of toxicity remain poorly understood.Additionally,ever evolving...Disinfection byproducts(DBPs)represent a ubiquitous source of chemical exposure in disinfected water.While over 700 DBPs have been identified,the drivers of toxicity remain poorly understood.Additionally,ever evolving water treatment practices have led to a continually growing list of DBPs.Advancement of analytical technologies have enabled the identification of new classes of DBPs and the quantification of these chemically diverse sets of DBPs.Here we summarize advances in new workflows for DBP analysis,including sample preparation,chromatographic separation with mass spectrometry(MS)detection,and data processing.To aid in the selection of techniques for future studies,we discuss necessary considerations for each step in the strategy.This review focuses on how each step of a workflow can be optimized to capture diverse classes of DBPs within a single method.Additionally,we highlight new MS-based approaches that can be powerful for identifying novel DBPs of toxicological relevance.We discuss current challenges and provide perspectives on future research directions with respect to studying new DBPs of toxicological relevance.As analytical technologies continue to advance,new strategies will be increasingly used to analyze complex DBPs produced in different treatment processes with the aim to identify potential drivers of toxicity.展开更多
Although disinfection byproducts(DBPs) in drinking water have been suggested as a cancer causing factor, the causative compounds have not yet been clarified. In this study, we used liquid chromatography quadrupole-tim...Although disinfection byproducts(DBPs) in drinking water have been suggested as a cancer causing factor, the causative compounds have not yet been clarified. In this study, we used liquid chromatography quadrupole-time-of-flight spectrometry(LC-QTOF MS) to identify the unknown disinfection byproducts(DBPs) in drinking water produced from Taihu Lake source water, which is known as a convergence point for the anthropogenic pollutants discharged from intensive industrial activities in the surrounding regions. In total, 91 formulas of DBPs were discovered through LC-QTOF MS nontarget screen, 81 of which have not yet been reported. Among the 91 molecules, 56 only contain bromine, 15 only contain chlorine and 20 DBPs have both bromine and chlorine atoms. Finally, five DBPs including 2,4,6-tribromophenol, 2,6-dibromo-4-chlorophenol, 2,6-dichloro-4-bromophenol, 4-bromo-2,6-di-tert-butylphenol and 3,6-dibromocarbazole were confirmed using standards. The former three compounds mainly formed in the predisinfection step(maximum concentration, 0.2-2.6 μg/L), while the latter two formed in the disinfection step(maximum concentration, 18.2-33.6 ng/L). In addition, 19 possible precursors of the discovered DBPs were detected, with the aromatic compounds being a major group. 2,6-di-tert-butylphenol as the precursor of 4-bromo-2,6-di-tert-butylphenol was confirmed with standard, with a concentration of 20.3 μg/L in raw water. The results of this study show that brominated DBPs which are possibly formed from industrial pollutants are relevant DBP species in drinking water produced form Taihu source water, suggesting protection of Taihu Lake source water is important to control the DBP risks.展开更多
It is thought that there are many unregulated anthropogenic chemicals in the environment.For risk assessment of chemicals, it is essential to estimate the predicted environmental concentrations. As an effort of identi...It is thought that there are many unregulated anthropogenic chemicals in the environment.For risk assessment of chemicals, it is essential to estimate the predicted environmental concentrations. As an effort of identifying residual organic contaminants in air and water in Korea, nontarget screening using two-dimensional gas chromatography time-of-flight mass spectrometry（GC × GC-TOFMS） was conducted at 10 sites using polyurethane foam passive air sampler and at 6 sites using polydimethyl siloxane（PDMS） passive water sampler in three different seasons in 2014. More than 600 chemical peaks were identified satisfying the identification criteria in air and water samples, respectively, providing a list for further investigation. Chemical substances with reported national emission rates in2014（n = 149） were also screened for potential existence in the environment using a level Ⅱ fugacity model. Most of chemical substances classified as not detectable were not identified with detection frequency greater than 20% by nontarget screening, indicating that a simple equilibrium model has a strong potential to be used to exclude chemicals that are not likely to remain in the environment after emissions from targeted monitoring.展开更多
In the present study, the herbicidal effects of two fungicides with the active ingredients expoxiconazole, fluxapyroxad, pyraclostrobin and fenpropimorph on the two arable weeds Lamium purpureum L. and Chenopodium alb...In the present study, the herbicidal effects of two fungicides with the active ingredients expoxiconazole, fluxapyroxad, pyraclostrobin and fenpropimorph on the two arable weeds Lamium purpureum L. and Chenopodium album L. were investigated. The experiments were conducted in a climate chamber under defined conditions. Sowing pods were prepared and plants at the cotyledon leaf stage were pricked out in test pods. Fungicides were applied at six application rates: 0%, 12.5%, 25%, 50%, 100% and 200% of the maximum registered dose rate in Germany. Seven days after application, the first assessment was conducted, regarding growth stage, quantity of plants and visible plant damage. Fourteen days after application, the second and final assessment was conducted, regarding growth stage, quantity of plants, visible plant damage and the fresh weight of the plants. There were herbicidal effects of the fungicides, which were presumably due to the active ingredient epoxiconazole. Epoxiconazole has effects on enzymes that are dependent on cytochrome P-450 and inhibits sterol biosynthesis and probably gibberellin synthesis. By doing so, these fungicides have similar effects to plant growth regulators. Weed species showed differential sensitivities, contractions and growth inhibition and ED50-values were calculated. Notwithstanding the probably minor relevance of the present results in agricultural practice, some effects on arable weeds might result if fungicides are applied at an early growth stage in the field. In some cases, the crop-weed competition could be shifted to the benefit of the crop. Nevertheless, the results are interesting for the field of weed research and for the assessment of the ecotoxicology of fungicides.展开更多
Cas12h1 is a compact CRISPR-associated nuclease from functionally diverse type V CRISPR-Cas effectors and recognizes a purine-rich protospacer adjacent motif(PAM)distinct from that of other type V Cas effectors.Here,w...Cas12h1 is a compact CRISPR-associated nuclease from functionally diverse type V CRISPR-Cas effectors and recognizes a purine-rich protospacer adjacent motif(PAM)distinct from that of other type V Cas effectors.Here,we report the nickase preference of Cas12h1,which predominantly cleaves the nontarget strand(NTS)of a double-stranded DNA(dsDNA)substrate.In addition,Cas12h1 acts as a nickase in human cells.We further determined the cryo-EM structures of Cas12h1 in the surveillance,R-loop formation,and interference states,revealing the molecular mechanisms involved in the crRNA maturation,target recognition,R-loop formation,nuclease activation and target degradation.Cas12h1 notably recognizes a broad 5’-DHR-3’PAM(D is A,G,or T;H is A,C,or T;R is A or G)both in vitro and in human cells.In addition,Cas12h1 utilizes a distinct activation mechanism that the lid motif undergoes a“flexible to stable”transition to expose the catalytic site to the substrate.A high-fidelity nucleic acid detector,Cas12h1hf,was developed through rational engineering,which distinguishes single-base mismatches and retains comparable on-target activities.Our results shed light on the molecular mechanisms underlying Cas12h1 nickase,improve the understanding of type V Cas effectors,and expand the CRISPR toolbox for genome editing and molecular diagnosis.展开更多
Currently,many countries and regions worldwide face the challenge of declining population growth due to persistently low rates of female reproduction.Since 2017,China's birth rate has hit historic lows and continu...Currently,many countries and regions worldwide face the challenge of declining population growth due to persistently low rates of female reproduction.Since 2017,China's birth rate has hit historic lows and continued to decline,with the death rate now equaling the birth rate.Concerns have emerged regarding the potential impact of environmental contaminants on reproductive health,including pregnancy loss.Endocrine-disrupting chemicals(EDCs)like phthalate esters(PAEs),bisphenol A(BPA),triclosan(TCS),and perfluoroalkyl substances(PFASs)have raised attention due to their adverse effects on biological systems.While China's 14th Five-Year Plan(2021–2025)for national economic and social development included the treatment of emerging pollutants,including EDCs,there are currently no national appraisal standards or regulatory frameworks for EDCs and their mixtures.Addressing the risk of EDC mixtures is an urgent matter that needs consideration from China's perspective in the near future.In this Perspective,we delve into the link between EDC mixture exposure and pregnancy loss in China.Our focus areas include establishing a comprehensive national plan targeting reproductive-aged women across diverse urban and rural areas,understanding common EDC combinations in women and their surrounding environment,exploring the relationship between EDCs and pregnancy loss via epidemiology,and reconsidering the safety of EDCs,particularly in mixtures and low-dose scenarios.We envision that this study could aid in creating preventive strategies and interventions to alleviate potential risks induced by EDC exposure during pregnancy in China.展开更多
Environmental pollution from synthetic chemical mixtures has significant adverse impacts on marine ecosystems.However,identifying the main constituents of chemical mixtures that pose ecological threats is challenging ...Environmental pollution from synthetic chemical mixtures has significant adverse impacts on marine ecosystems.However,identifying the main constituents of chemical mixtures that pose ecological threats is challenging due to the necessity of an integrated workflow for comprehensive identification and toxicological prioritization of pollutants.Here,an all-in-one mass spectrometric strategy integrating target,suspect,and nontarget analysis was used to investigate organic pollutants of concern in fishing port sediments,with 355 pollutants(32 from target analysis,118 from suspect screening and 205 from nontarget analysis)identified in 11 categories.The chemical classes of polycyclic aromatic hydrocarbons(PAHs),pesticides,and intermediates were the extensively detected chemical classes.The ecological risks of absolutely quantified pollutants(i.e.,16 parent PAHs,7 organophosphate esters(OPEs),10 pesticides and 4 benzotriazole ultraviolet absorbers)were assessed using toxicity-weighted concentration ranking,with o,p’-DDT being the major contributor.Under the toxicological priority index(ToxPi)framework,an extended ranking of all identified pollutants was achieved by combining instrument response and detection frequency,with a priority control list of 15 pollutants obtained,of which benzo[ghi]perylene(BghiP)and p,p’-DDE had the highest risk priority.Due to frequent detection rates and significant environmental risks,routine monitoring of petroleum pollutants is considered essential.This study presents a general workflow that includes comprehensive identification and prioritization of pollutants,facilitating chemical management and ecological risk assessment.展开更多
With long-term production and widespread application,per-and polyfluoroalkyl substances(PFAS)have been detected in various media worldwide,including the atmosphere.Since the gradual restriction and phase-out of C8 per...With long-term production and widespread application,per-and polyfluoroalkyl substances(PFAS)have been detected in various media worldwide,including the atmosphere.Since the gradual restriction and phase-out of C8 perfluoroalkyl acids(PFAAs),environmental contamination by emerging PFAS substitutes such as short-chain PFAA homologues,perfluoroether carboxylic,and sulfonic acids has been reported.Although there has been extensive monitoring of emerging PFAS substitutes in the aquatic environment,few studies have conducted target analysis and nontarget screening(NTS)of emerging unknown PFAS in the atmosphere over the past decade.To fill the gap,this review focused on emerging PFAS in the atmosphere in addition to legacy PFAS.The reported sampling,pretreatment,and instrumental analysis methods for target analysis and NTS of both neutral and ionic PFAS in the atmosphere are summarized,along with the advantages and current limitations of different sampling and NTS methods for PFAS in the atmosphere.The global levels,composition,and spatiotemporal distribution characteristics of legacy and emerging PFAS in the atmosphere are summarized and their transport,transformation,and dry/wet deposition are elucidated.The review highlights the importance of developing and applying the all-in-one strategy integrating target,suspect screening,and NTS to gain insights into emerging PFAS in the atmosphere and provide a reference for future research.展开更多
RNA interference(RNAi)has emerged as a powerful tool for developing novel management strategies for controlling insect pests.The 28-spotted ladybeetle,Henosepilachna vigintioctopunctata is one of the most important pe...RNA interference(RNAi)has emerged as a powerful tool for developing novel management strategies for controlling insect pests.The 28-spotted ladybeetle,Henosepilachna vigintioctopunctata is one of the most important pests attacking solanaceous plants in Asia.In this study,the potential of dietary RNAi to manage H.vigintioctopunctata was investigated using both in vitro synthesized and bacterially expressed double-stranded RNAs(dsRNAs)of HvvATPase A and HvvATPase E.The expression levels of HvvATPase A and HvvATPase E were higher in Malpighian tubules than in other tissue types.The silencing of HvvATPase A and HvvATPase E led to significant mortality in H.vigintioctopunctata larvae.In addition,the ingestion of HvvATPase A and HvvATPase E significantly deterred feeding behavior and subsequently arrested the development of H.vigintioctopunctata.Notably,the bacterially expressed dsRNAs consistently caused higher mortality in larvae and adults.Finally,the nontarget effects of the dsRNAs of H.vigintioctopunctata on the predatory ladybeetle Propylaea japonica were evaluated.P.japonica 1st instar larvae were administered vATPase A and vATPase E dsRNAs from H.vigintioctopunctata and P.japonica under the worst-case scenario,in which dsGFP served as negative control.There were significant effects of dsHvvATPase A on P.japonica at the transcriptional level but not at the organismal level,whereas dsHvvATPase E did not effect P.japonica at either the transcriptional or the organismal level.Collectively,the results of the study suggest that HvvATPase A and HvvATPase E can act as novel molecular targets for the control of H.vigintioctopunctata.展开更多
Despite their positive effect in reducing pest populations, exotic generalist predators sometimes become invasive and contribute to the displacement of indigenous species in the same trophic level. Although laboratory...Despite their positive effect in reducing pest populations, exotic generalist predators sometimes become invasive and contribute to the displacement of indigenous species in the same trophic level. Although laboratory experiments have linked intraguild predation （IGP） to these interactions, field evidence and quantification of IGP are still lacking for most systems. The recent establishment of the exotic Harmonia axyridis （Pallas） （Coleoptera： Coccinellidae） in Italy raises concern about the detrimental effect that the ladybird could have on native coccinellids. Here we assessed, under laboratory conditions, the acceptability and suitability of eggs of 2 native ladybirds, Adalia bipunctata L. and Oenopia conglobata （L.）, as prey items for H. axyridis larvae. Then we developed primers for molecular gut-content analysis to detect predation by H. axyridis on the 2 ladybirds and on the aphid Eucallipterus tiliae L. Species-specific 16S primers were developed for the 3 species and laboratory feeding trials were conducted to quantify the rate of prey DNA breakdown in the gut of//. axyridis. Moreover, to field evaluate primers, H. axyridis 4th instars （n = 132） were systematically collected from linden trees in northern Italy and screened for the presence of prey DNA. Seventy-three percent and 7% of field collected H. axyridis were positive for aphid and coccinellid DNA, respectively. Predation upon aphid and A. bipunctata was lower than predicted if density dependent consumption was expected, while predation upon O. conglobata was significantly higher. Here, we provided the first evidence of IGP among feral populations ofH. axyridis and indigenous ladybird beetles, occurring in Italy.展开更多
Environmental impacts of genetically modified crops are mandatorily assessed during their premarket phase. One of the areas of concern is the possible impact on nontar- get organisms. Crops expressing Cry toxins might...Environmental impacts of genetically modified crops are mandatorily assessed during their premarket phase. One of the areas of concern is the possible impact on nontar- get organisms. Crops expressing Cry toxins might affect Lepidoptera larvae living outside cultivated fields, through pollen deposition on wild plants, which constitute their food source. While pollen toxicity varies among different events, possible exposure ofnontarget species depends on the agro-environmental conditions. This study was conducted in two protected areas in Italy, characterized by different climatic conditions, where many Lepi- doptera species thrive in proximity to maize cultivations. To estimate the possible exposure in absence of the actual stressor （e.g., Cryl-expressing maize plants）, we conducted a two-year field survey of butterflies and weeds. Indicator species were selected--Aglais （Inachis） io in the Northern site and Vanessa cardui in the Southern site--and their phe- nology was investigated. Pollen dispersal from maize fields was measured by collection in Petri dishes. Duration and frequency of exposure was defined by the overlap between pollen emission and presence of larvae on host plants. Different risk scenarios are expected in the two regions： highest exposure is foreseen forA. io in the Northern site, while minimal exposure is estimated for V. cardui in the Southern site. In the latter case, locally grown maize cultivars flower in mid-summer in coincidence with an aestivation period for several butterfly species due to hot and dry conditions. Moreover, host plants of V. cardui are at the end of their life cycle thus limiting food availability.展开更多
American chestnut(Castanea dentata[Marsh.]Borkh.)was once the dominant hardwood species in Eastern North America before an exotic fungal pathogen,Cryphonec-tria parasitica(Murrill)Barr,functionally eliminated it acros...American chestnut(Castanea dentata[Marsh.]Borkh.)was once the dominant hardwood species in Eastern North America before an exotic fungal pathogen,Cryphonec-tria parasitica(Murrill)Barr,functionally eliminated it across its range.One promising approach toward restoring American chestnut to natural forests is development of blight-tolerant trees using genetic transformation.However,transformation and related processes can result in unexpected and unintended phenotypic changes,potentially altering ecologi-cal interactions.To assess unintended tritrophic impacts of transgenic American chestnut on plant herbivore interactions,gypsy moth(Lymantria dispar L.)caterpillars were fed leaf disks excised from two transgenic events,Darling 54 and Darling 58,and four control American chestnut lines.Leaf disks were previously treated with an LDso dose of either the speces-specific Lymantria dispar multiple nucleopolyhedrovirus(LdMNPV)or the generalist pathogen Bacillus thuringiensis subsp.kurstaki(Btk).Mortality was quantified and compared to water blank controls.Tree genotype had a strong efect on the efficacies of both pathogens.Larval mortality from Btk-treated foliage from only one transgenic event,Darling 54,differed from its isogenic progenitor,Ellis l,but was similar to an unre-lated wild-type American chestnut control.LdMNPV efficacy was unaffected by genetic transformation.Results suggest that although genetic modification of trees may affect interactions with other nontarget organisms,this may be due to insertion effects,and varia-tion amnon diMterent genvtypes(wlether uasgeic ul wild-typc)iupaults a giealci change in response than transgene presence.展开更多
Fungicides are used to control pathogenic fungi of crop species,but they have also been shown to alter behavioral,life history and fitness related traits of nontarget insects.Here,we tested the fungicide effects on fe...Fungicides are used to control pathogenic fungi of crop species,but they have also been shown to alter behavioral,life history and fitness related traits of nontarget insects.Here,we tested the fungicide effects on feeding behavior,survival and physiology of the nontarget pest insect,the Colorado potato beetle(CPB)(Leptinotarsa decemlineata).Feeding behavior was studied by a choice test of adult beetles,which were allowed to choose between a control and a fungicide(fluazinam)treated potato leaf.Larval survival was recorded after 24 and 72 h exposure to control and fungicide-treated leaves with 2 different concentrations.The adults did not show fungicide avoidance behavior.Similarly,survival of the larvae was not affected by the exposure to fungicides.Finally,to understand the effects of fungicides at the physiological level(gene expression),we tested whether the larval exposure to fungicide alter the expression of 5 metabolic pathway and stress associated genes.Highest concentration and 72-h exposure caused upregulation of 1 cytochrome P450(CYP9Z14v2)and 1 insecticide resistance gene(Ldace1),whereas metabolic detoxification gene(Ugt1)was downregulated.At 24-h exposure,highest concentration caused downregulation of another common detoxification gene(Gs),while both exposure times to lowest concentration caused upregulation of the Hsp70 stress tolerance gene.Despite these overall effects,there was a considerable amount of variation among different families in the gene expression levels.Even though the behavioral effects of the fungicide treatments were minor,the expression level differences of the studied genes indicate changes on the metabolic detoxifications and stress-related pathways.展开更多
基金supported by grants from the Natural Sciences and Engineering Research Council of Canada,Alberta Innovatesthe Canada Research Chairs Program。
文摘The combination of hydrogen/deuterium(H/D)formaldehyde-based isotopic methyl labeling with solid-phase extraction and high-performance liquid chromatography–high resolution mass spectrometry(HPLC-HRMS)is a powerful analytical solution for nontargeted analysis of trace-level amino-containing chemicals in water samples.Given the huge amount of chemical information generated in HPLC-HRMS analysis,identifying all possible H/Dlabeled amino chemicals presents a significant challenge in data processing.To address this,we designed a streamlined data processing pipeline that can automatically extract H/D-labeled amino chemicals from the raw HPLC-HRMS data with high accuracy and efficiency.First,we developed a cross-correlation algorithm to correct the retention time shift resulting from deuterium isotopic effects,which enables reliable pairing of H-and D-labeled peaks.Second,we implemented several bioinformatic solutions to remove false chemical features generated by in-source fragmentation,salt adduction,and natural13C isotopes.Third,we used a data mining strategy to construct the AMINES library that consists of over 38,000 structure-disjointed primary and secondary amines to facilitate putative compound annotation.Finally,we integrated these modules into a freely available R program,HDPairFinder.R.The rationale of each module was justified and its performance tested using experimental H/D-labeled chemical standards and authentic water samples.We further demonstrated the application of HDPairFinder to effectively extract N-containing contaminants,thus enabling the monitoring of changes of primary and secondary N-compounds in authentic water samples.HDPairFinder is a reliable bioinformatic tool for rapid processing of H/D isotopic methyl labeling-based nontargeted analysis of water samples,and will facilitate a better understanding of N-containing chemical compounds in water.
基金supported by grants from the Natural Sciences and Engineering Research Council of Canada,Alberta Health,and Alberta Innovates-Energy and Environment Solutions
文摘A broad range of organic compounds are known to exist in drinking water sources and serve as precursors of disinfection byproducts（DBPs）.Epidemiological findings of an association of increased risk of bladder cancer with the consumption of chlorinated water has resulted in health concerns about DBPs.Peptides are thought to be an important category of DBP precursors in water.However,little is known about the actual presence of peptides and their DBPs in drinking water because of their high sample complexity and low concentrations.To address this challenge and identify peptides and non-chlorinated/chlorinated peptide DBPs from large sets of organic compounds in water,we developed a novel high throughput analysis strategy,which integrated multiple solid phase extraction（SPE）,high performance liquid chromatography（HPLC）separation,and non-target identification using precursor ion exclusion（PIE）high resolution mass spectrometry（MS）.After MS analysis,structures of candidate compounds,particularly peptides,were obtained by searching against the Human Metabolome Database（HMDB）.Using this strategy,we successfully detected 625 peptides（out of 17,205 putative compounds）and 617 peptides（out of 13,297）respectively in source and finished water samples.The source and finished water samples had 501 peptides and amino acids in common.The remaining 116 peptides and amino acids were unique to the finished water.From a subset of 30 putative compounds for which standards were available,25 were confirmed using HPLC-MS analysis.By analyzing the peptides identified in source and finished water,we successfully confirmed three disinfection reaction pathways that convert peptides into toxic DBPs.
文摘Intact pZ189 DNA was replicated in monkey kidney vero cells which had been pretreated with Nmethyl-N’-nitro-N-nitrosoguanidine (MNNG) . The mutants were selected in E. coli MBM7070 and the mutation frequencies involving mutants with unchanged electrophoretic mobilrty of their plasmid DNA were scored. When compared to the spontaneous mutation frequency. the mutation frequencies were increased by 5.8 and 2.9-fold in cells pretreated with 0. 2 and 2μmol/L MNNG, respectively. The supF genes of these mutants were sequenced. and it was found that the types of base substitution and the sites of frameshifts differed from findings in studies of spontaneous and targeted mutagenesis. The results suggest that nontargeted mutagenesis occurs in mammalian cells and may have a sequence specificity.
文摘Among the expressed sequence tags (ESTs) which were isolated from genetically instable monkey kidney vero cells induced by N-methyI-N’-nitro-N-nitrosoguanidine (MNNG), a fragment 9 was isolated. When the expression of fragment 9 was blocked through transcripting antisense RNA, MNNGinduced nontargeted mutation frequency enhanced significantly compared with control ( P 【 0.05). The result showed that the relevant gene of fragment 9 might participate in maintaining cellular genetic stability and be involved in inhibition of nontargeted mutagenesis.
文摘The introduction of drug-eluting stents has significantly reduced the incidence of in-stent restenosis.Despite this,recurrent cardiovascular events related to untreated nontarget lesions(NTLs)are becoming more common and accounting for more than 50%of all recurrent cardiovascular events.In patients with dia-betes,factors such as prolonged disease duration,poor glycemic control,insulin use,and inadequate lipid management may exacerbate the progression of NTLs and adverse cardiovascular events.Additionally,glycemic fluctuations have been linked to an increased risk of future cardiovascular events in patients with early glucose metabolism abnormalities and acute hyperglycemia.In this review,we explored the clinical and plaque characteristics of patients with diabetes and early glucose metabolism disorders,the percutaneous coronary intervention strategies for NTLs,and their prognostic implications.Furthermore,we investigated the mechanistic links between adverse cardiovascular outcomes and elevated inflammation,oxidative stress,hypercoagulability,and endothelial dysfunction.
文摘BACKGROUND The relationship between metabolic syndrome(MetS)and gastric cancer(GC),which is a common metabolic disease,has attracted much attention.However,the specific metabolic characteristics of MetS in elderly patients with GC remain unclear.AIM To investigate the differentially abundant metabolites and metabolic pathways between preoperative frailty and MetS in elderly patients with GC based on nontargeted metabolomics techniques.METHODS In this study,125 patients with nonfrail nonmeal GC were selected as the control group,and 50 patients with GC in the frail group were selected as the frail group.Sixty-five patients with GC combined with MetS alone were included in the MetS group,and 50 patients with GC combined with MetS were included in the MetS group.Nontargeted metabolomics techniques were used to measure plasma metabolite levels by ultrahigh-performance liquid chromatography-mass spectrometry.Multivariate statistical analysis was performed by principal component analysis,orthogonal partial least squares,pattern recognition analysis,cluster analysis,and metabolic pathway annotation.RESULTS A total of 125 different metabolites,including amino acids,glycerophospholipids,sphingolipids,fatty acids,sugars,nucleosides and nucleotides,and acidic compounds,were identified via nontargeted metabolomics techniques.Compared with those in the control group,there were 41,32,and 52 different metabolites in the MetS group,the debilitated group,and the combined group,respectively.Lipid metabolites were significantly increased in the MetS group.In the weak group,amino acids and most glycerol phospholipid metabolites decreased significantly,and fatty acids and sphingosine increased significantly.The combined group was characterized by significantly increased levels of nucleotide metabolites and acidic compounds.The alanine,aspartic acid,and glutamate metabolic pathways were obviously enriched in the asthenic group,and the glycerol and phospholipid metabolic pathways were obviously enriched in the combined group.CONCLUSION Elderly GC patients with simple frailty,simple combined MetS,and frailty combined with MetS have different metabolic characteristics,among which amino acid and glycerophospholipid metabolite levels are significantly lower in frail elderly GC patients,and comprehensive supplementation of fat and protein should be considered.Many kinds of metabolites,such as amino acids,lipids,nucleotides,and acidic compounds,are abnormally abundant in patients with MetS combined with fthenia,which may be related to tumor-related metabolic disorders.
文摘Disinfection byproducts(DBPs)represent a ubiquitous source of chemical exposure in disinfected water.While over 700 DBPs have been identified,the drivers of toxicity remain poorly understood.Additionally,ever evolving water treatment practices have led to a continually growing list of DBPs.Advancement of analytical technologies have enabled the identification of new classes of DBPs and the quantification of these chemically diverse sets of DBPs.Here we summarize advances in new workflows for DBP analysis,including sample preparation,chromatographic separation with mass spectrometry(MS)detection,and data processing.To aid in the selection of techniques for future studies,we discuss necessary considerations for each step in the strategy.This review focuses on how each step of a workflow can be optimized to capture diverse classes of DBPs within a single method.Additionally,we highlight new MS-based approaches that can be powerful for identifying novel DBPs of toxicological relevance.We discuss current challenges and provide perspectives on future research directions with respect to studying new DBPs of toxicological relevance.As analytical technologies continue to advance,new strategies will be increasingly used to analyze complex DBPs produced in different treatment processes with the aim to identify potential drivers of toxicity.
基金This work was supported by Major Science and Technology Program for Water Pollution Control and Treatment(No.2017ZX07502003)the National Key R&D Program of China(No.2018YFE0204101).
文摘Although disinfection byproducts(DBPs) in drinking water have been suggested as a cancer causing factor, the causative compounds have not yet been clarified. In this study, we used liquid chromatography quadrupole-time-of-flight spectrometry(LC-QTOF MS) to identify the unknown disinfection byproducts(DBPs) in drinking water produced from Taihu Lake source water, which is known as a convergence point for the anthropogenic pollutants discharged from intensive industrial activities in the surrounding regions. In total, 91 formulas of DBPs were discovered through LC-QTOF MS nontarget screen, 81 of which have not yet been reported. Among the 91 molecules, 56 only contain bromine, 15 only contain chlorine and 20 DBPs have both bromine and chlorine atoms. Finally, five DBPs including 2,4,6-tribromophenol, 2,6-dibromo-4-chlorophenol, 2,6-dichloro-4-bromophenol, 4-bromo-2,6-di-tert-butylphenol and 3,6-dibromocarbazole were confirmed using standards. The former three compounds mainly formed in the predisinfection step(maximum concentration, 0.2-2.6 μg/L), while the latter two formed in the disinfection step(maximum concentration, 18.2-33.6 ng/L). In addition, 19 possible precursors of the discovered DBPs were detected, with the aromatic compounds being a major group. 2,6-di-tert-butylphenol as the precursor of 4-bromo-2,6-di-tert-butylphenol was confirmed with standard, with a concentration of 20.3 μg/L in raw water. The results of this study show that brominated DBPs which are possibly formed from industrial pollutants are relevant DBP species in drinking water produced form Taihu source water, suggesting protection of Taihu Lake source water is important to control the DBP risks.
基金supported by the National Institute of Environmental Research(No.NIER-RP-2014-335)
文摘It is thought that there are many unregulated anthropogenic chemicals in the environment.For risk assessment of chemicals, it is essential to estimate the predicted environmental concentrations. As an effort of identifying residual organic contaminants in air and water in Korea, nontarget screening using two-dimensional gas chromatography time-of-flight mass spectrometry（GC × GC-TOFMS） was conducted at 10 sites using polyurethane foam passive air sampler and at 6 sites using polydimethyl siloxane（PDMS） passive water sampler in three different seasons in 2014. More than 600 chemical peaks were identified satisfying the identification criteria in air and water samples, respectively, providing a list for further investigation. Chemical substances with reported national emission rates in2014（n = 149） were also screened for potential existence in the environment using a level Ⅱ fugacity model. Most of chemical substances classified as not detectable were not identified with detection frequency greater than 20% by nontarget screening, indicating that a simple equilibrium model has a strong potential to be used to exclude chemicals that are not likely to remain in the environment after emissions from targeted monitoring.
文摘In the present study, the herbicidal effects of two fungicides with the active ingredients expoxiconazole, fluxapyroxad, pyraclostrobin and fenpropimorph on the two arable weeds Lamium purpureum L. and Chenopodium album L. were investigated. The experiments were conducted in a climate chamber under defined conditions. Sowing pods were prepared and plants at the cotyledon leaf stage were pricked out in test pods. Fungicides were applied at six application rates: 0%, 12.5%, 25%, 50%, 100% and 200% of the maximum registered dose rate in Germany. Seven days after application, the first assessment was conducted, regarding growth stage, quantity of plants and visible plant damage. Fourteen days after application, the second and final assessment was conducted, regarding growth stage, quantity of plants, visible plant damage and the fresh weight of the plants. There were herbicidal effects of the fungicides, which were presumably due to the active ingredient epoxiconazole. Epoxiconazole has effects on enzymes that are dependent on cytochrome P-450 and inhibits sterol biosynthesis and probably gibberellin synthesis. By doing so, these fungicides have similar effects to plant growth regulators. Weed species showed differential sensitivities, contractions and growth inhibition and ED50-values were calculated. Notwithstanding the probably minor relevance of the present results in agricultural practice, some effects on arable weeds might result if fungicides are applied at an early growth stage in the field. In some cases, the crop-weed competition could be shifted to the benefit of the crop. Nevertheless, the results are interesting for the field of weed research and for the assessment of the ecotoxicology of fungicides.
基金supported by the National Key Research and Development Program of China(2021YFC2301403)National Natural Science Foundation of China grants(82225028 and 82172287)Natural Science Foundation of Fujian Province of China(2022J01638).
文摘Cas12h1 is a compact CRISPR-associated nuclease from functionally diverse type V CRISPR-Cas effectors and recognizes a purine-rich protospacer adjacent motif(PAM)distinct from that of other type V Cas effectors.Here,we report the nickase preference of Cas12h1,which predominantly cleaves the nontarget strand(NTS)of a double-stranded DNA(dsDNA)substrate.In addition,Cas12h1 acts as a nickase in human cells.We further determined the cryo-EM structures of Cas12h1 in the surveillance,R-loop formation,and interference states,revealing the molecular mechanisms involved in the crRNA maturation,target recognition,R-loop formation,nuclease activation and target degradation.Cas12h1 notably recognizes a broad 5’-DHR-3’PAM(D is A,G,or T;H is A,C,or T;R is A or G)both in vitro and in human cells.In addition,Cas12h1 utilizes a distinct activation mechanism that the lid motif undergoes a“flexible to stable”transition to expose the catalytic site to the substrate.A high-fidelity nucleic acid detector,Cas12h1hf,was developed through rational engineering,which distinguishes single-base mismatches and retains comparable on-target activities.Our results shed light on the molecular mechanisms underlying Cas12h1 nickase,improve the understanding of type V Cas effectors,and expand the CRISPR toolbox for genome editing and molecular diagnosis.
基金supported by the National Key Research and Development Program of China(2023YFC3706600)the National Natural Science Foundation of China(22225605)the K.C.Wong Education Foundation of China(GJTD-2020-03).
文摘Currently,many countries and regions worldwide face the challenge of declining population growth due to persistently low rates of female reproduction.Since 2017,China's birth rate has hit historic lows and continued to decline,with the death rate now equaling the birth rate.Concerns have emerged regarding the potential impact of environmental contaminants on reproductive health,including pregnancy loss.Endocrine-disrupting chemicals(EDCs)like phthalate esters(PAEs),bisphenol A(BPA),triclosan(TCS),and perfluoroalkyl substances(PFASs)have raised attention due to their adverse effects on biological systems.While China's 14th Five-Year Plan(2021–2025)for national economic and social development included the treatment of emerging pollutants,including EDCs,there are currently no national appraisal standards or regulatory frameworks for EDCs and their mixtures.Addressing the risk of EDC mixtures is an urgent matter that needs consideration from China's perspective in the near future.In this Perspective,we delve into the link between EDC mixture exposure and pregnancy loss in China.Our focus areas include establishing a comprehensive national plan targeting reproductive-aged women across diverse urban and rural areas,understanding common EDC combinations in women and their surrounding environment,exploring the relationship between EDCs and pregnancy loss via epidemiology,and reconsidering the safety of EDCs,particularly in mixtures and low-dose scenarios.We envision that this study could aid in creating preventive strategies and interventions to alleviate potential risks induced by EDC exposure during pregnancy in China.
基金supported by the National Key Research and Development Program(2022YFC3105500)the National Natural Science Foundation of China(42206159)the Dalian Young Star of Science and Technology Project(2022RQ052).
文摘Environmental pollution from synthetic chemical mixtures has significant adverse impacts on marine ecosystems.However,identifying the main constituents of chemical mixtures that pose ecological threats is challenging due to the necessity of an integrated workflow for comprehensive identification and toxicological prioritization of pollutants.Here,an all-in-one mass spectrometric strategy integrating target,suspect,and nontarget analysis was used to investigate organic pollutants of concern in fishing port sediments,with 355 pollutants(32 from target analysis,118 from suspect screening and 205 from nontarget analysis)identified in 11 categories.The chemical classes of polycyclic aromatic hydrocarbons(PAHs),pesticides,and intermediates were the extensively detected chemical classes.The ecological risks of absolutely quantified pollutants(i.e.,16 parent PAHs,7 organophosphate esters(OPEs),10 pesticides and 4 benzotriazole ultraviolet absorbers)were assessed using toxicity-weighted concentration ranking,with o,p’-DDT being the major contributor.Under the toxicological priority index(ToxPi)framework,an extended ranking of all identified pollutants was achieved by combining instrument response and detection frequency,with a priority control list of 15 pollutants obtained,of which benzo[ghi]perylene(BghiP)and p,p’-DDE had the highest risk priority.Due to frequent detection rates and significant environmental risks,routine monitoring of petroleum pollutants is considered essential.This study presents a general workflow that includes comprehensive identification and prioritization of pollutants,facilitating chemical management and ecological risk assessment.
基金supported by the National Natural Science Foundation of China(Grant Nos.22036004,22006074,42161134001,and 41807356)the Ministry of Science and Technology(Grant Nos.2023YFC3706805 and 2022YFC3703201)the 111 Program,Ministry of Education,China(Grant No.T2017002).
文摘With long-term production and widespread application,per-and polyfluoroalkyl substances(PFAS)have been detected in various media worldwide,including the atmosphere.Since the gradual restriction and phase-out of C8 perfluoroalkyl acids(PFAAs),environmental contamination by emerging PFAS substitutes such as short-chain PFAA homologues,perfluoroether carboxylic,and sulfonic acids has been reported.Although there has been extensive monitoring of emerging PFAS substitutes in the aquatic environment,few studies have conducted target analysis and nontarget screening(NTS)of emerging unknown PFAS in the atmosphere over the past decade.To fill the gap,this review focused on emerging PFAS in the atmosphere in addition to legacy PFAS.The reported sampling,pretreatment,and instrumental analysis methods for target analysis and NTS of both neutral and ionic PFAS in the atmosphere are summarized,along with the advantages and current limitations of different sampling and NTS methods for PFAS in the atmosphere.The global levels,composition,and spatiotemporal distribution characteristics of legacy and emerging PFAS in the atmosphere are summarized and their transport,transformation,and dry/wet deposition are elucidated.The review highlights the importance of developing and applying the all-in-one strategy integrating target,suspect screening,and NTS to gain insights into emerging PFAS in the atmosphere and provide a reference for future research.
基金supported by the National Key R&D Program of China(2017YFD0200900)National Natural Science Foundation of China(31972269)GDUPS(2017).
文摘RNA interference(RNAi)has emerged as a powerful tool for developing novel management strategies for controlling insect pests.The 28-spotted ladybeetle,Henosepilachna vigintioctopunctata is one of the most important pests attacking solanaceous plants in Asia.In this study,the potential of dietary RNAi to manage H.vigintioctopunctata was investigated using both in vitro synthesized and bacterially expressed double-stranded RNAs(dsRNAs)of HvvATPase A and HvvATPase E.The expression levels of HvvATPase A and HvvATPase E were higher in Malpighian tubules than in other tissue types.The silencing of HvvATPase A and HvvATPase E led to significant mortality in H.vigintioctopunctata larvae.In addition,the ingestion of HvvATPase A and HvvATPase E significantly deterred feeding behavior and subsequently arrested the development of H.vigintioctopunctata.Notably,the bacterially expressed dsRNAs consistently caused higher mortality in larvae and adults.Finally,the nontarget effects of the dsRNAs of H.vigintioctopunctata on the predatory ladybeetle Propylaea japonica were evaluated.P.japonica 1st instar larvae were administered vATPase A and vATPase E dsRNAs from H.vigintioctopunctata and P.japonica under the worst-case scenario,in which dsGFP served as negative control.There were significant effects of dsHvvATPase A on P.japonica at the transcriptional level but not at the organismal level,whereas dsHvvATPase E did not effect P.japonica at either the transcriptional or the organismal level.Collectively,the results of the study suggest that HvvATPase A and HvvATPase E can act as novel molecular targets for the control of H.vigintioctopunctata.
文摘Despite their positive effect in reducing pest populations, exotic generalist predators sometimes become invasive and contribute to the displacement of indigenous species in the same trophic level. Although laboratory experiments have linked intraguild predation （IGP） to these interactions, field evidence and quantification of IGP are still lacking for most systems. The recent establishment of the exotic Harmonia axyridis （Pallas） （Coleoptera： Coccinellidae） in Italy raises concern about the detrimental effect that the ladybird could have on native coccinellids. Here we assessed, under laboratory conditions, the acceptability and suitability of eggs of 2 native ladybirds, Adalia bipunctata L. and Oenopia conglobata （L.）, as prey items for H. axyridis larvae. Then we developed primers for molecular gut-content analysis to detect predation by H. axyridis on the 2 ladybirds and on the aphid Eucallipterus tiliae L. Species-specific 16S primers were developed for the 3 species and laboratory feeding trials were conducted to quantify the rate of prey DNA breakdown in the gut of//. axyridis. Moreover, to field evaluate primers, H. axyridis 4th instars （n = 132） were systematically collected from linden trees in northern Italy and screened for the presence of prey DNA. Seventy-three percent and 7% of field collected H. axyridis were positive for aphid and coccinellid DNA, respectively. Predation upon aphid and A. bipunctata was lower than predicted if density dependent consumption was expected, while predation upon O. conglobata was significantly higher. Here, we provided the first evidence of IGP among feral populations ofH. axyridis and indigenous ladybird beetles, occurring in Italy.
文摘Environmental impacts of genetically modified crops are mandatorily assessed during their premarket phase. One of the areas of concern is the possible impact on nontar- get organisms. Crops expressing Cry toxins might affect Lepidoptera larvae living outside cultivated fields, through pollen deposition on wild plants, which constitute their food source. While pollen toxicity varies among different events, possible exposure ofnontarget species depends on the agro-environmental conditions. This study was conducted in two protected areas in Italy, characterized by different climatic conditions, where many Lepi- doptera species thrive in proximity to maize cultivations. To estimate the possible exposure in absence of the actual stressor （e.g., Cryl-expressing maize plants）, we conducted a two-year field survey of butterflies and weeds. Indicator species were selected--Aglais （Inachis） io in the Northern site and Vanessa cardui in the Southern site--and their phe- nology was investigated. Pollen dispersal from maize fields was measured by collection in Petri dishes. Duration and frequency of exposure was defined by the overlap between pollen emission and presence of larvae on host plants. Different risk scenarios are expected in the two regions： highest exposure is foreseen forA. io in the Northern site, while minimal exposure is estimated for V. cardui in the Southern site. In the latter case, locally grown maize cultivars flower in mid-summer in coincidence with an aestivation period for several butterfly species due to hot and dry conditions. Moreover, host plants of V. cardui are at the end of their life cycle thus limiting food availability.
基金Thanks to Hannah Nadel(USDA-APHIS)for kindly providing gypsy moth larvae,and John Podgwaite(USDA Forest Service)for providing purified LdM-NPV.We gratefully acknowledge Seaira Goetz and Elliot Hunsinger for their outstanding technical assistance in the laboratory.Substantive comments by T.Horton and M.K.Fierke improved earlier versions of the manuscript.This project was supported by Biotechnology Risk Assessment Grant Program competitive grant No.2012-33522-19863 from the USDA National Institute of Food and.Agriculture.
文摘American chestnut(Castanea dentata[Marsh.]Borkh.)was once the dominant hardwood species in Eastern North America before an exotic fungal pathogen,Cryphonec-tria parasitica(Murrill)Barr,functionally eliminated it across its range.One promising approach toward restoring American chestnut to natural forests is development of blight-tolerant trees using genetic transformation.However,transformation and related processes can result in unexpected and unintended phenotypic changes,potentially altering ecologi-cal interactions.To assess unintended tritrophic impacts of transgenic American chestnut on plant herbivore interactions,gypsy moth(Lymantria dispar L.)caterpillars were fed leaf disks excised from two transgenic events,Darling 54 and Darling 58,and four control American chestnut lines.Leaf disks were previously treated with an LDso dose of either the speces-specific Lymantria dispar multiple nucleopolyhedrovirus(LdMNPV)or the generalist pathogen Bacillus thuringiensis subsp.kurstaki(Btk).Mortality was quantified and compared to water blank controls.Tree genotype had a strong efect on the efficacies of both pathogens.Larval mortality from Btk-treated foliage from only one transgenic event,Darling 54,differed from its isogenic progenitor,Ellis l,but was similar to an unre-lated wild-type American chestnut control.LdMNPV efficacy was unaffected by genetic transformation.Results suggest that although genetic modification of trees may affect interactions with other nontarget organisms,this may be due to insertion effects,and varia-tion amnon diMterent genvtypes(wlether uasgeic ul wild-typc)iupaults a giealci change in response than transgene presence.
基金supported by the Finish Cultural foundation and the Academy of Finland(Grant NO.308302 to LL and 322980 to MK).
文摘Fungicides are used to control pathogenic fungi of crop species,but they have also been shown to alter behavioral,life history and fitness related traits of nontarget insects.Here,we tested the fungicide effects on feeding behavior,survival and physiology of the nontarget pest insect,the Colorado potato beetle(CPB)(Leptinotarsa decemlineata).Feeding behavior was studied by a choice test of adult beetles,which were allowed to choose between a control and a fungicide(fluazinam)treated potato leaf.Larval survival was recorded after 24 and 72 h exposure to control and fungicide-treated leaves with 2 different concentrations.The adults did not show fungicide avoidance behavior.Similarly,survival of the larvae was not affected by the exposure to fungicides.Finally,to understand the effects of fungicides at the physiological level(gene expression),we tested whether the larval exposure to fungicide alter the expression of 5 metabolic pathway and stress associated genes.Highest concentration and 72-h exposure caused upregulation of 1 cytochrome P450(CYP9Z14v2)and 1 insecticide resistance gene(Ldace1),whereas metabolic detoxification gene(Ugt1)was downregulated.At 24-h exposure,highest concentration caused downregulation of another common detoxification gene(Gs),while both exposure times to lowest concentration caused upregulation of the Hsp70 stress tolerance gene.Despite these overall effects,there was a considerable amount of variation among different families in the gene expression levels.Even though the behavioral effects of the fungicide treatments were minor,the expression level differences of the studied genes indicate changes on the metabolic detoxifications and stress-related pathways.
