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Hybrid lead halide perovskites have received extensive scientific attention owing to their great potential in the field of fluorescent displays and light-emitting diodes. Currently, most luminescent materials contain functional molecular and rare-earth metal ion parts. However, the mechanism of photoluminescence property in two-dimensional hybrid lead halide perovskites with different layered inorganic skeletons has been reported rarely. To better understand the effect of an inorganic skeleton on the fluorescence property, here, we report three organic-inorganic hybrid materials with different layered inorganic frameworks: (MACH)2·PbBr4 (Prv-1, MACH = cyclohexylmethylammonium), (2-MPQ)·PbBr4 (Prv-2, 2-MPQ = 2-methylpiperazinium), and (TMBA)4·Pb3Br10 (Prv-3, TMBA = N'N'N'-trimethylbenzylammonium). Among them, Prv-1 is a (100)-oriented perovskite, Prv-2 belongs to the (110)-oriented perovskite, and the inorganic framework of Prv-3 possesses [Pb3Br10] units. Interestingly, Prv-1 has a strong blue-violet fluorescence emission, while the luminescence effect of Prv-2 is very weak; notably, Prv-3 emits a charming bright-orange light. Meanwhile, results of theoretical computational studies also reveal that the electronic structure of all three compounds is highly dependent on structurally distorted [PbBr6] octahedra, and the frontier molecular orbital (FMO) analysis further suggests that HOMO and LUMO of Prv-3 are contributed by inorganic and organic components, respectively. In addition, all three materials belong to direct band gap semiconductors, and the band gaps are 2.79, 2.97, and 2.76 eV, respectively. Significantly, there are obvious differences in conduction bands. Based on the above analysis, the photoluminescence mechanism of three hybrid materials is explained from the electronic levels. Consequentially, this work might provide practical strategies and perspectives for exploring novel structure-related properties.
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Studies show that tropical and mid-latitude terrestrial ectotherms are more vulnerable to global warming than species from high latitudes. However, thermal tolerance studies from these regions still lack soil invertebrates. In the present study, we investigated six euedaphic species of Collembola (of the genera Onychiurus and Protaphorura) sampled across latitudes ranging from 31° N to 64° N and determined their upper thermal limit (UTL) by static assays. In another experiment, we submitted springtails to high temperatures for exposure times, causing 5% to 30% mortality within each species. Survivors from this series of increasing heat injuries were used to determine the time-to-first-oviposition and the number of eggs produced following heat exposure. Two hypotheses are tested in this study: 1) heat tolerance of species correlates positively with the environmental temperature of their habitat; 2) the most heat-tolerant species require less time to regain reproduction and produce more eggs than the least heat-tolerant species. Results showed that the UTL positively correlates to the soil temperature of the sampling site. The sequence of UTL60 (the temperature causing 50% mortality after 60â¯min of exposure) from highest to least was O. yodaiâ¯>â¯P. fimataâ¯>â¯P. armataâ¯≈â¯P. tricampataâ¯>â¯P. macfadyeniâ¯>â¯P. pseudovanderdrifti. Heat stress inflicted on springtails can delay reproduction in all species, and two species showed a reduced egg production rate after heat exposure. For heat stress causing up to 30% mortality, the most heat-tolerant species did not have advantages over the least heat-tolerant species for what concerns the recovery of reproduction. The relation between UTL and recovery from heat stress is not linear. Our study provides evidence for a potential long-term effect of high-temperature exposure on euedaphic species of Collembola and highlights the need for further studies on the effects of global warming on soil-living organisms.
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Artrópodes , Animais , Temperatura , Invertebrados , Temperatura Alta , Solo , ReproduçãoRESUMO
Organic-inorganic Hybrid (OIH) materials for multifunctional switchable applications have attracted enormous attention in recent years due to their excellent optoelectronic properties and good structural tunability. However, it still remains challenging to fabricate one simple OIH compound with multi-functionals properties, such as dielectric switching, thermochromic properties, semiconductor characteristics and ferroelasticity. Under this context, we successfully synthesized [2-(2-fluorophenyl)ethan-1- ammonium]2 SnBr6 (compound 1), which has a higher phase transition temperature of 427.7â K. Additionally, it exhibits a semiconducting property with an indirect band gap of 2.36â eV. Combining ferroelastic, narrow band gap, thermochromic, and dielectric properties, compound 1 can be considered as a rarely reported multi-functional ferroelastic material, which is expected to give inspiration for broadening the applications in the smart devices field.
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Semicondutores , Transição de FaseRESUMO
Hydrogen doping of metal oxide semiconductors is promising for manipulation of their properties toward various applications. Yet it is quite challenging because it requires harsh reaction conditions and expensive metal catalysts. Meanwhile, acids as a cheap source of protons have long been unappreciated. Here, we develop a sophisticated acid-metal treatment for tunable hydrogenation of metal oxides at ambient conditions. Using first-principles simulations, we first show that, with proper work function difference between the metal and metal oxide, H-diffusion into negatively charged metal oxide can be well controlled, resulting in tunable H-doping of metal oxides with quasi-metal characteristics. This has been verified by proof-of-concept experiments that achieved the controllable hydrogenation of WO3 using Cu and hydrochloric acid at ambient conditions. Further, H-doping of other metal oxides (TiO2/Nb2O5/MoO3) has been achieved by metal-acid treatment and induced a change in properties. Our work provides a promising way to tailor metal oxides via tunable H-doping.
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Extensive efforts have been devoted to construct a fiber-shaped energy-storage device to fulfill the increasing demand for power consumption of textile-based wearable electronics. Despite the myriad of available material selections and device architectures, it is still fundamentally challenging to develop eco-friendly fiber-shaped aqueous rechargeable batteries (FARBs) on a single-fiber architecture with high energy density and long-term stability. Here, we demonstrate flexible and high-voltage coaxial-fiber aqueous rechargeable zinc-ion batteries (CARZIBs). By utilizing a novel spherical zinc hexacyanoferrate with prominent electrochemical performance as cathode material, the assembled CARZIB offers a large capacity of 100.2 mAh cm-3 and a high energy density of 195.39 mWh cm-3, outperforming the state-of-the-art FARBs. Moreover, the resulting CARZIB delivers outstanding flexibility with the capacity retention of 93.2% after bending 3000 times. Last, high operating voltage and output current are achieved by the serial and parallel connection of CARZIBs woven into the flexible textile to power high-energy-consuming devices. Thus, this work provides proof-of-concept design for next-generation wearable energy-storage devices.
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Charge doping is an effective way to induce the metal-insulator transition (MIT) in correlated materials for many important utilizations, which is however practically limited by problem of low stability. An electron-proton co-doping mechanism is used to achieve pronounced phase modulation of monoclinic vanadium dioxide (VO2 ) at room temperature. Using l-ascorbic acid (AA) solution to treat VO2 , the ionized AA- species donate electrons to the adsorbed VO2 surface. Charges then electrostatically attract surrounding protons to penetrate, and eventually results in stable hydrogen-doped metallic VO2 . The variations of electronic structures, especially the electron occupancy of Vâ 3d/Oâ 2p hybrid orbitals, were examined by synchrotron characterizations and first-principle theoretical simulations. The adsorbed molecules protect hydrogen dopants from escaping out of lattice and thereby stabilize the metallic phase for VO2 .
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Sequential change-point detection when the distribution parameters are unknown is a fundamental problem in statistics and machine learning. When the post-change parameters are unknown, we consider a set of detection procedures based on sequential likelihood ratios with non-anticipating estimators constructed using online convex optimization algorithms such as online mirror descent, which provides a more versatile approach to tackling complex situations where recursive maximum likelihood estimators cannot be found. When the underlying distributions belong to a exponential family and the estimators satisfy the logarithm regret property, we show that this approach is nearly second-order asymptotically optimal. This means that the upper bound for the false alarm rate of the algorithm (measured by the average-run-length) meets the lower bound asymptotically up to a log-log factor when the threshold tends to infinity. Our proof is achieved by making a connection between sequential change-point and online convex optimization and leveraging the logarithmic regret bound property of online mirror descent algorithm. Numerical and real data examples validate our theory.
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Chitin synthesis inhibitors (CSIs) are commonly used insecticides compromising cuticle formation and structure in arthropods. Arthropods rely on intact cuticles to maintain water balance and cellular homeostasis to survive in different weather conditions. We hypothesized that physiological impacts of CSIs may make arthropods more vulnerable to harsh environmental conditions, such as extreme heat, cold or drought. The aim of this study was to investigate if pre-exposure to teflubenzuron (a common CSI) would influence Folsomia candida's (Collembola: Isotomidae) sensitivity to natural stressors. Here, we exposed adult collembolans to teflubenzuron through food for two weeks, then survivors were immediately divided into three groups for subsequent acute heat, cold, and drought exposure. After acute exposure to these natural stressors, the collembolans were moved to optimal conditions for a one-week recovery period during which their survival, time to regain reproduction, and egg production were examined. We analyzed the interaction between effects of teflubenzuron and natural stressors using a multiplicative model. No interaction between effects of teflubenzuron and heat was observed in any test endpoints. A synergistic interaction between effects of teflubenzuron and cold was observed in the time to regain reproduction. Both survival and egg production, on the other hand, showed synergistic interaction between effects of teflubenzuron and drought, as well as a tendency for longer reproduction recovery times. Our results suggest that pre-exposure to teflubenzuron reduces drought tolerance in F. candida, while its impact on heat or cold tolerance is minor or absent. This study is among the first to explore the combined effects of CSI and natural stressors on soil arthropods, providing more insight on potential risks posed by such chemicals in the environment.
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Artrópodes , Benzamidas , Secas , Artrópodes/efeitos dos fármacos , Artrópodes/fisiologia , Animais , Benzamidas/farmacologia , Benzamidas/toxicidade , Inseticidas/toxicidade , Reprodução/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Quitina , Resistência à SecaRESUMO
Current standard toxicity tests on nontarget soil invertebrates mainly focus on the endpoints survival and reproduction. Such results are likely insufficient to predict effects at higher organizational levels, for example, the population level. We assessed the effects of exposure to the pesticide teflubenzuron on the collembolan Folsomia candida, by performing a full life-cycle experiment exposing single individuals via contaminated food (uncontaminated control and 0.2, 0.32, 0.48, 0.72, 1.08, and 1.6 mg/kg dry yeast). Several life-history traits were considered by following the growth and development of newly hatched individuals over a period of 65 days. We assessed survival, body length, time to first oviposition, cumulative egg production, and hatchability of eggs. A two-stage model was applied to calculate the population growth rate (λ) combined with elasticity analysis to reveal the relative sensitivity of λ to the effects of teflubenzuron on each life-history parameter. Body length was the least sensitive life-history parameter (median effective concentration = 1.10 mg teflubenzuron/kg dry yeast) followed by time to first oviposition (0.96 mg/kg), survival (median lethal concentration = 0.87 mg/kg), cumulative egg production (0.32 mg/kg), and egg hatchability (0.27 mg/kg). Population growth decreased with increasing concentrations of teflubenzuron (λ = 1.162/day in control to 1.005/day in 0.72 mg/kg dry yeast, with populations going extinct at 1.08 and 1.6 mg/kg dry yeast). Elasticity analysis showed that changes in juvenile survival had a greater impact on the population growth rate compared with the other life-history traits. Our study provides a comprehensive overview of individual-level effects of long-term exposure to teflubenzuron and integrates these effects to assess the potential risk to collembolan populations. Environ Toxicol Chem 2024;43:1173-1183. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
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Artrópodes , Benzamidas , Hormônios Juvenis , Crescimento Demográfico , Animais , Hormônios Juvenis/toxicidade , Hormônios Juvenis/farmacologia , Benzamidas/toxicidade , Benzamidas/farmacologia , Artrópodes/efeitos dos fármacos , Estágios do Ciclo de Vida/efeitos dos fármacos , Éteres Fenílicos/toxicidade , FemininoRESUMO
Borocarbonitride (BCN) materials have shown significant potential as photocatalysts for hydrogen production. However, traditional bulk BCN exhibits only moderate photocatalytic activity. In this study, we introduce an environmentally conscious and sustainable strategy utilizing biomass-derived carbon sources to synthesize BCN nanosheets. The hydrogen evolution efficiency of BCN-A nanosheets (110 µmol h-1 g-1) exceeds that of bulk BCN photocatalysts (12 µmol h-1 g-1) by 9.1 times, mainly due to the increased surface area (205 m2g-1) and the presence of numerous active sites with enhanced charge separation capabilities. Notably, the biomass-derived BCN nanosheets offer key advantages such as sustainability, cost-effectiveness, and reduced carbon footprint during hydrogen production. These findings highlight the potential of biomass-based BCN nanomaterials to facilitate a greener and more efficient route to hydrogen energy, contributing to the global transition towards renewable energy solutions.
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The volatile organic compounds (VOCs) of Rhizoma Acori Tatarinowii were extracted via steam distillation and then irradiated with 60Co-γ rays, in which doses of 60Co-γ 0, 5, and 10 kGy were selected to irradiate the VOCs. Finally, gas chromatography-ion mobility spectrometry (GC-IMS) was used to compare the differences between the VOCs, and then qualitatively analyse the components and contents of each part of the VOCs The results showed that under the three irradiation doses of 60Co-γ 0, 5 and 10 kGy, the VOCs of unirradiated and 5 kGy-irradiated samples were closer, and the samples irradiated at a 10 kGy dose were quite different from the other two components, meaning that when the calamus medicinal materials were sterilised by means of 60Co irradiation, the dose of 5 kGy was closer to the original compound content of the medicinal materials.
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This study analyzes the distribution of pathogenic bacteria and their antimicrobial susceptibilities in elderly patients with cardiovascular diseases to identify risk factors for pulmonary infections. A risk prediction model is established, aiming to serve as a clinical tool for early prevention and management of pulmonary infections in this vulnerable population. A total of 600 patients were categorized into infected and uninfected groups. Independent risk factors such as older age, diabetes history, hypoproteinemia, invasive procedures, high cardiac function grade, and a hospital stay of ≥10 days were identified through logistic regression. A predictive model was constructed, with a Hosmer-Lemeshow goodness of fit (P = 0.236) and an area under the receiver operating characteristic curve of 0.795, demonstrating good discriminative ability. The model had 63.40% sensitivity and 82.80% specificity, with a cut-off value of 0.13. Our findings indicate that the risk score model is valid for identifying high-risk groups for pulmonary infection among elderly cardiovascular patients. The study contributes to the early prevention and control of pulmonary infections, potentially reducing infection rates in this vulnerable population.
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Temperature variability in soils is expected to increase due to the more frequent occurrence of heat waves, putting species under thermal stress. In addition, organic pollutants such as polycyclic aromatic hydrocarbons (PAHs) are released into the environment due to anthropogenic activities. Both stressors negatively impact terrestrial organisms and may interact with each other. Here, we subjected the soil living enchytraeid, Enchytraeus albidus, to combined exposure to phenanthrene (PHE; 0, 10, 20, 40, and 80 mg kg-1 dry soil) and a range of temperature treatments (constant temperature (CT): 10, 15 and 20 °C; different mean temperature with the same daily temperature fluctuation (DTF-5): 10 ± 5, 15 ± 5 and 20 ± 5 °C; daily temperature fluctuation with the same mean, but different amplitudes (DTF-A): 20, 20 ± 2, 20 ± 5 and 20 ± 7 °C). We measured internal PHE concentration in adults and found that an increase in mean temperature significantly increased the internal PHE concentration. The production of juveniles was measured using a standardized test. We found a synergistic interaction between the temperature amplitude (DTF-A treatments) and PHE on the reproduction of E. albidus. The EC50 of reproduction decreased with increasing amplitude. These results show that the negative effects of PHE on E. albidus can be magnified if stressful temperatures are reached (although briefly) during diurnal fluctuations of soil temperature. Our results highlight the importance and inclusion of extreme thermal events in the risk assessment of pollutants.
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Poluentes Ambientais , Oligoquetos , Fenantrenos , Poluentes do Solo , Animais , Temperatura , Solo , Fenantrenos/toxicidade , Poluentes do Solo/toxicidadeRESUMO
Neonicotinoid insecticides are harmful to non-target soil invertebrates, which are crucial for sustainable agriculture. Gene expression biomarkers could provide economic and high-throughput metrics of neonicotinoid exposure and toxicity to non-target invertebrates. Thereby, biomarkers can help guide remediation efforts or policy enforcement. Gene expression of Glutathione S-Transferase 3 (GST3) has previously been proposed as a biomarker for the neonicotinoid imidacloprid in the soil ecotoxicological model species Folsomia candida (Collembola). However, it remains unclear how reliably gene expression of neonicotinoid biomarkers, such as GST3, can indicate the exposure to the broader neonicotinoid family under putative GST enzymatic inhibition. In this work, we exposed springtails to two neonicotinoids, thiacloprid and imidacloprid, alongside diethyl maleate (DEM), a known GST metabolic inhibitor that imposes oxidative stress. First, we determined the influence of DEM on neonicotinoid toxicity to springtail fecundity. Second, we surveyed the gene expression of four biomarkers, including GST3, under mutual exposure to neonicotinoids and DEM. We observed no effect of DEM on springtail fecundity. Moreover, the expression of GST3 was only influenced by DEM under mutual exposure with thiacloprid but not with imidacloprid. The results indicate that GST3 is not a robust indicator of neonicotinoid exposure and that probable GST enzymatic inhibition mediates the toxicity of imidacloprid and thiacloprid differentially. Future research should investigate biomarker reliability under shifting metabolic conditions such as provided by DEM exposure.
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Artrópodes , Inseticidas , Animais , Reprodutibilidade dos Testes , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Invertebrados , Inseticidas/toxicidade , Glutationa Transferase , Solo , BiomarcadoresRESUMO
Organic-inorganic halide perovskites (OIHPs) are very eye-catching due to their chemical tunability and rich physical properties such as ferroelectricity, magnetism, photovoltaic properties and photoluminescence. However, no nickel-based OIHP ferroelectrics have been reported so far. Here, we designed an ABX3 OIHP ferroelectric (3-pyrrolinium)NiCl3, where the 3-pyrrolinium cations are located on the voids surrounded by one-dimensional chains composed of NiCl6-face-sharing octahedra via hydrogen bonding interactions. Such a unique structure enables the (3-pyrrolinium)NiCl3 with a high spontaneous polarization (P s) of 5.8 µC cm-2 and a high Curie temperature (T c) of 428 K, realizing dramatic enhancement of 112 and 52 K compared to its isostructural (3-pyrrolinium)MCl3 (M = Cd, Mn). To our knowledge, remarkably, (3-pyrrolinium)NiCl3 should be the first case of nickel(ii)-based OIHP ferroelectric to date, and its T c of 428 K (35 K above that of BaTiO3) is the highest among all reported one-dimensional OIHP ferroelectrics. This work offers a new structural building block for enriching the family of OIHP structures and will inspire the further exploration of new nickel(ii)-based OIHP ferroelectrics.
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The complete genome sequence of a Chinese narcissus isolate of narcissus late season yellows virus from Zhangzhou, China (NLSYV-ZZ), was determined to be 9,651 nucleotides in length, excluding the 3'-terminal poly (A) tail, by amplification and sequencing of virus RNA. The viral genome contains a single long open reading frame of 9,315 nucleotides encoding a polyprotein of 3,105 amino acids. The polyprotein was predicted to be cleaved into ten mature proteins by three viral proteases. Complete genome sequence comparison and phylogenetic analysis indicated that NLSYV-ZZ was most closely related to narcissus yellow stripe virus (NYSV), which was also isolated from narcissus. These viruses shared 69.9 % identity in their complete nucleotide sequences and 77.0 % identity in their polyprotein amino acid sequences.
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Genoma Viral , Narcissus/virologia , Doenças das Plantas/virologia , Potyvirus/genética , RNA Viral/genética , Análise de Sequência de DNA , China , Análise por Conglomerados , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia , Poliproteínas/genética , Potyvirus/isolamento & purificação , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Proteínas Virais/genéticaRESUMO
OBJECTIVE: To detect pharmacokinetics of Danshensu Sodium in Danshen dripping solution in Beagles. METHOD: Danshen dripping solution was dripped intravenously into healthy Beagles at a dose of 10 mL x kg(-1). Their plasma samples were extracted with acetic ether, the blood concentrations were determined by HPLC method. RESULT: Danshensu Sodium showed a good linear relationship within the range of 0.225-18.000 mg x L(-1), with the lowest detectable limit of 0.113 mg x L(-1). Its pharmacokinetic parameters were as follows: tmax was 30 min, Cmax was (9.5742 +/- 2.3715) mg x L(-1), t1/2 was (19.23 +/- 2.97) min, CL was (0.0127 +/- 0.0030) L x min(-1) x kg(-1), AUC(0-tn) was (474.954 +/- 95.483) mg x min x L(-1) and AUC(0-infinity) was (482.494 +/- 95.353) mg x min x L(-1). CONCLUSION: The accurate, stable and reliable blood concentration method shows a one-compartment mode of Danshensu Sodium in Beagles.
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Medicamentos de Ervas Chinesas/farmacocinética , Lactatos/farmacocinética , Animais , Cromatografia Líquida de Alta Pressão , Cães , Estabilidade de Medicamentos , Feminino , Masculino , SoluçõesRESUMO
Multifunctional switching materials show great potential for applications in sensors, smart switches, and other fields due to their ability to integrate different physical channels in one single device. However, multifunctional responsive materials with multiple switching and luminescence properties have rarely been reported. Here, we report three organic-inorganic hybrids: [TMAA]2[CoCl4] (compound 1), [TMAA]2[CdBr4] (compound 2) and [TMAA]2[MnCl4] (compound 3). Compound 1 and compound 2 undergo two reversible phase transitions at high temperature (328.95/359.25 K and 350.45/393.15 K, respectively). Since the inorganic skeleton has a strong influence on the luminescence properties of such structured substances, Cd and Co were replaced with Mn, after which compound 3 was obtained as expected. The above strategy triggered bright green luminescence with a quantum yield of 35.19%, and significantly increased the phase transition temperature of compound 3 to above 400 K. The above results show that the regulation of the inorganic skeleton provides a new strategy for researchers to develop dual phase change/luminous materials.
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Pesticide toxicity is typically assessed by exposing model organisms to individual compounds and measuring effects on survival and reproduction. These tests are time-consuming, labor-intensive, and do not accurately capture the effect of pesticide mixtures. Moreover, it is unfeasible to screen the nearly infinite combinations of mixtures for synergistic effects on model organisms. Therefore, reliable molecular indicators of pesticide exposure have to be identified, i.e., biomarkers. These biomarkers can form the basis of rapid and economical screening procedures to assess the toxicity of pesticides even under synergistic interaction with other pollutants. In this study, we screened the expression patterns of eight genes for suitability as a biomarker for neonicotinoid exposure in the soil ecotoxicological model Folsomia candida (springtails). Springtails were exposed to the neonicotinoids imidacloprid and thiacloprid either alone or with various levels of piperonyl butoxide (PBO), which inhibits cytochrome P450 enzymes (CYPs): a common point of synergistic interaction between neonicotinoid and other pesticides. First, we confirmed PBO as a potency enhancer for neonicotinoid toxicity to springtail fecundity, and then used it as a tool to confirm biomarker robustness. We identified two genes that are reliably indicative for neonicotinoid exposure even under metabolic inhibition of CYPs by PBO, nicotinic acetylcholine receptor-subunit alpha 1 (nAchR) and sodium-coupled monocarboxylate transporter (SMCT). These results can form the basis for developing high-throughput screening procedures for neonicotinoid exposure in varying mixture compositions.
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Artrópodes , Poluentes Ambientais , Inseticidas , Praguicidas , Receptores Nicotínicos , Animais , Butóxido de Piperonila/toxicidade , Solo , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Biomarcadores , SódioRESUMO
BACKGROUND: Accumulating evidence implicates leukocyte telomere length (LTL) shortening as a potential risk predictor for cardiovascular disease. Arterial stiffness chronicles the cumulative burden of cardiovascular disease risk factors. Therefore, the capacity of LTL to predict arterial stiffness was examined. METHODS: A total of 275 unrelated Chinese males: 163 patients with coronary artery disease (CAD) and 112 healthy controls, 40-73 years of age were included in this study. The relative telomere length of leukocytes was determined by a real-time fluorescence quantitative polymerase chain reaction (PCR). Large artery stiffness was measured with carotid-femoral pulse wave velocity (PWV). RESULTS: The relative telomere length (T/S) ratio was significantly shorter in patients with CAD (0.79 +/- 0.26) than in control subjects (1.08 +/- 0.22) (p<0.001). The correlation between LTL and PWV in patients with CAD was stronger than that in the controls (r= -0.467, r(2)=0.227, p<0.001 for patients with CAD versus r= -0.223; r(2)=0.050; p=0.018 for controls). The log(e)-transformed T/S ratio was inversely correlated with age (r= -0.345; p<0.001), PWV (r= -0.326; p<0.001) and C-reactive protein ( r= -0.133; p=0.027). CONCLUSIONS: The data show an association of leukocyte telomere length shortening with increased arterial stiffness and cardiovascular burden, suggesting that telomere length is a biomarker of large artery elasticity and CAD. Further studies are warranted to study the role of LTL dynamics in the pathogenesis of atherosclerosis.