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1.
Conserv Biol ; : e14253, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38516741

RESUMO

Because global anthropogenic activities cause vast biodiversity loss, human dimensions research is essential to forming management plans applicable to biodiversity conservation outside wilderness areas. Engaging public participation is crucial in this context to achieve social and environmental benefits. However, knowledge gaps remain in understanding how a balance between conservation and public demands can be reached and how complicated sociocultural contexts in the Anthropocene can be incorporated in conservation planning. We examined China's nationwide conflict between free-ranging cats (owned cats that are allowed to go outdoors or homeless cats living outdoors) and wildlife to examine how a consensus between compassion and biodiversity conservation can help in decision-making. We surveyed a random sample of people in China online. Over 9000 questionnaires were completed (44.2% response). In aggregate, respondents reported approximately 29 million free-ranging owned cats and that over 5 million domestic cats per year become feral in mainland China. Respondents who were cat owners, female, and religious were more likely to deny the negative impacts of cats on wildlife and ongoing management strategies and more supportive of stray cat shelters, adoption, and community-based fund raising than nonowners, male, and nonreligious respondents (p < 0.05). Free-ranging cat ownership and abandonment occurred less with owners with more knowledge of biodiversity and invasive species than with respondents with less knowledge of these subjects (p < 0.05). We recommend that cat enthusiasts and wildlife conservationists participate in community-based initiatives, such as campaigns to keep cats indoors. Our study provides a substantially useful framework for other regions where free-ranging cats are undergoing rapid expansion.


Retos y oportunidades de las dimensiones humanas detrás del conflicto entre gatos y fauna Resumen Debido a que las actividades antropogénicas globales causan una enorme pérdida de la biodiversidad, la investigación sobre las dimensiones humanas es esencial para generar planes de manejo aplicables a la conservación de la biodiversidad fuera de las áreas silvestres. Es muy importante lograr que el público participe en este contexto para obtener los beneficios sociales y ambientales. Sin embargo, todavía existen vacíos en el conocimiento sobre cómo lograr el balance entre la conservación y las demandas públicas y cómo incorporar los contextos socioculturales complejos del Antropoceno a la planeación de la conservación. Analizamos el conflicto nacional entre los gatos libres (gatos callejeros o gatos domésticos que se les permite salir) y la fauna en China para estudiar cómo un consenso entre la compasión y la conservación de la biodiversidad puede ayudar en la toma de decisiones. Encuestamos en línea a una muestra aleatoria de personas en China. Se completaron más de 9000 cuestionarios (44.2% de respuesta). En total, los respondientes reportaron un aproximado de 29 millones de gatos libres y que más de cinco millones de gatos domésticos se vuelven ferales al año en China. Quienes respondieron y son dueños de gatos, mujeres y religiosos tuvieron la mayor probabilidad de negar los impactos negativos de los gatos sobre la fauna y de las estrategias actuales de manejo y de mostrar más apoyo por los refugios de gatos abandonados, la adopción y de la recaudación de fondos comunitaria que quienes no son dueños, no son religiosos y son hombres (p < 0.05). La propiedad de gatos libres y el abandono ocurrieron menos con los dueños con más conocimiento sobre la biodiversidad y las especies invasoras que con los respondientes con menos conocimiento sobre estos temas (p < 0.05). Recomendamos que los aficionados a los gatos y los conservacionistas de la fauna participen en las iniciativas comunitarias; por ejemplo, campañas para mantener a los gatos dentro de casa. Nuestro estudio proporciona un marco sustancialmente útil para otras regiones en donde los gatos libres se encuentran en rápida expansión.

2.
Curr Zool ; 70(1): 45-58, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38476135

RESUMO

Group living animals form striking aggregation patterns and display synchronization, polarization, and collective intelligence. Though many collective behavioral studies have been conducted on small animals like insects and fish, research on large animals is still rare due to the limited availability of field collective data. We used drones to record videos and analyzed the decision-making and behavioral spatial patterns in orientation of Kiang (Tibetan wild ass, Equus kiang). Leadership is unevenly distributed among Kiang, with the minority initiating majority behavior-shift decisions. Decisions of individual to join are driven by imitation between group members, and are largely dependent on the number of members who have already joined. Kiang respond to the behavior and position of neighbors through different strategies. They strongly polarize when moving, therefore adopting a linear alignment. When vigilant, orientation deviation increases as they form a tighter group. They remain scattered while feeding and, in that context, adopt a side-by-side alignment. This study reveals partially-shared decision-making among Kiang, whereby copying neighbors provides the wisdom to thrive in harsh conditions. This study also suggests that animals' spatial patterns in orientation depend largely on their behavioral states in achieving synchronization.

3.
Math Biosci Eng ; 20(12): 21186-21210, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38124593

RESUMO

Sketch image retrieval is an important branch of the image retrieval field, mainly relying on sketch images as queries for content search. The acquisition process of sketch images is relatively simple and in some scenarios, such as when it is impossible to obtain photos of real objects, it demonstrates its unique practical application value, attracting the attention of many researchers. Furthermore, traditional generalized sketch image retrieval has its limitations when it comes to practical applications; merely retrieving images from the same category may not adequately identify the specific target that the user desires. Consequently, fine-grained sketch image retrieval merits further exploration and study. This approach offers the potential for more precise and targeted image retrieval, making it a valuable area of investigation compared to traditional sketch image retrieval. Therefore, we comprehensively review the fine-grained sketch image retrieval technology based on deep learning and its applications and conduct an in-depth analysis and summary of research literature in recent years. We also provide a detailed introduction to three fine-grained sketch image retrieval datasets: Queen Mary University of London (QMUL) ShoeV2, ChairV2 and PKU Sketch Re-ID, and list common evaluation metrics in the sketch image retrieval field, while showcasing the best performance achieved for these datasets. Finally, we discuss the existing challenges, unresolved issues and potential research directions in this field, aiming to provide guidance and inspiration for future research.

4.
Sci Total Environ ; 902: 165944, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37543345

RESUMO

Metal-organic frameworks (MOFs) are a new class of crystalline porous hybrid materials with high porosity, large specific surface area and adjustable channel structure and biocompatibility, which are being investigated with increasing interest for energy storage and conversion, gas adsorption/separation, catalysis, sensing and biomedicine. However, the practical applications of MOFs make them release into the environment inevitable, posing a threat to humans and organisms. In this article, we cover advances in the currently available MOFs synthesis methods and the emerging applications of MOFs, especially in the biomedical field (therapeutic agents and bioimaging). Additionally, after evaluating the current status of main exposure routes and affecting factors in the field of MOFs-toxicity, the molecular mechanism is also clarified and identified. Knowledge gaps are identified from such a summarization and frontier development are explored for MOFs. Afterwards, we also present the limitations, challenges, and future perspectives in the study of the entire life cycle of MOFs. This review emphasizes the need for a more targeted discussion of the latest, widely used and effective versatile material class in order to exploit the full potential of high-performance and non-toxicity MOFs in the future.

5.
Anal Chem ; 95(19): 7416-7421, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37138452

RESUMO

Usually, different assays and instrumentation are required for different types of targets, e.g., nucleic acids, proteins, small molecules, etc., because of significant differences in their structures and sizes. To increase efficiency and reduce costs, a desirable solution is to develop a versatile platform suitable for diverse objectives. Here, we established a versatile detection technique: first, target separation and enrichment were carried out using magnetic beads (MBs); then, different targets were converted to same barcoded DNA strands (BDs) released from gold nanoparticles; finally, sensitive detection of three different targets (miRNA-21, digoxigenin antibody, and aflatoxin B1) was achieved through exonuclease III (Exo III) cyclic cleavage-assisted signal amplification. To simplify the operation, we integrated this technique into a microfluidic chip with multiple chambers in which the requisite reagents were prestored. Just by moving the MBs through different chambers with a magnet, multiple steps can be completed. Due to the limited space in microfluidic chips, the full mixing of MBs and solution is a key point to improve reaction efficiency. The mixing can be achieved by acoustic vibration generated by a small, portable sonic toothbrush. Based on the microfluidic chip, the detection limits of the above three targets were 0.76 pM, 0.16 ng/mL, and 0.56 nM, respectively. Furthermore, miRNA-21 and Digoxigenin antibody (Dig-Ab) in serum and AFB1 in corn powder were also used to demonstrate the performance of this chip. Our versatile platform is easy to operate and is expected to develop into an automatic "sample-to-answer" device.


Assuntos
Nanopartículas Metálicas , MicroRNAs , Técnicas Analíticas Microfluídicas , Microfluídica , Ouro/química , Digoxigenina , Nanopartículas Metálicas/química , Anticorpos
6.
Environ Sci Technol ; 57(13): 5380-5390, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36942846

RESUMO

As a group of new nanomaterials, nanoscale metal-organic frameworks (MOFs) are widely applied in the biomedical field, exerting unknown risks to the human body, especially the central nervous system. Herein, the impacts of MOF-74-Zn nanoparticles on neurological behaviors and neurotransmitter metabolism are explored in both in vivo and in vitro assays modeled by C57BL/6 mice and PC12 cells, respectively. The mice exhibit increased negative-like behaviors, as demonstrated by the observed decrease in exploring behaviors and increase in despair-like behaviors in the open field test and forced swimming test after exposure to low doses of MOF-74-Zn nanoparticles. Disorders in the catecholamine neurotransmitter metabolism may be responsible for the MOF-74-Zn-induced abnormal behaviors. Part of the reason for this is the inhibition of neurotransmitter synthesis caused by restrained neurite extension. In addition, MOF-74-Zn promotes the translocation of more calcium into the cytoplasm, accelerating the release and uptake and finally resulting in an imbalance between synthesis and catabolism. Taken together, the results from this study indicate the human toxicity risks of nanoscale low-toxicity metal-based MOFs and provide valuable insight into the rational and safe use of MOF nanomaterials.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Ratos , Animais , Camundongos , Humanos , Catecolaminas , Zinco/toxicidade , Camundongos Endogâmicos C57BL
7.
Nat Commun ; 12(1): 3828, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34158511

RESUMO

There is accelerating interest in developing memory devices using antiferromagnetic (AFM) materials, motivated by the possibility for electrically controlling AFM order via spin-orbit torques, and its read-out via magnetoresistive effects. Recent studies have shown, however, that high current densities create non-magnetic contributions to resistive switching signals in AFM/heavy metal (AFM/HM) bilayers, complicating their interpretation. Here we introduce an experimental protocol to unambiguously distinguish current-induced magnetic and nonmagnetic switching signals in AFM/HM structures, and demonstrate it in IrMn3/Pt devices. A six-terminal double-cross device is constructed, with an IrMn3 pillar placed on one cross. The differential voltage is measured between the two crosses with and without IrMn3 after each switching attempt. For a wide range of current densities, reversible switching is observed only when write currents pass through the cross with the IrMn3 pillar, eliminating any possibility of non-magnetic switching artifacts. Micromagnetic simulations support our findings, indicating a complex domain-mediated switching process.

8.
Sci Total Environ ; 771: 145063, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33736171

RESUMO

Metal-organic frameworks (MOFs) exhibit broad potential applications in the environmental, biomedical, catalyst, and energy fields. However, the currently existing data hardly shed light on their health risks before the MOFs' large-scale usage. In this context, we exploratively investigated the in vivo fate and effect of one representative cobalt-based zeolitic imidazolate framework (ZIF-67) at the nano- (60 nm) and submicron- (890 nm) scales. Different from submicron-scale ZIF-67 showing better biosafety, nanoscale particles manifested a neurodegenerative risk at the dose of no general toxicity, evidenced by the impairment of learning and memory ability and disordered function of the neuropeptide signaling pathway in a rat model. The involvement of oxidative damage and inflammatory processes in the neurotoxicity induced by ZIF-67 was discussed as well. These findings not only provide a wake-up call for the prudent applications of MOFs but also provide insight into the better design and safer use of MOFs for broader applications.


Assuntos
Estruturas Metalorgânicas , Zeolitas , Animais , Catálise , Cobalto/toxicidade , Estruturas Metalorgânicas/toxicidade , Ratos , Zeolitas/toxicidade
9.
Sci Total Environ ; 731: 139071, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32438088

RESUMO

Organophosphate esters (OPEs) are used as additives in flame retardants and plasticizers. Due to phase out of several congeners of polybrominated diphenyl ethers (PBDEs), the application of organophosphorus flame retardants (OPFRs) is continuously increasing over the years. As a consequence, large amounts of OPEs enter the environment. Sewage and solid waste (especially e-waste) treatment plants are the important sources of OPEs released to the environment. Other sources include emissions of OPE-containing materials and vehicle fuel into the atmosphere. OPEs are widely detected in air, dust, water, soil, sediment and sludge. To know the pollution situation of OPEs, a variety of methods on their pretreatment and determination have been developed. We discussed and compared the analytical methods of OPEs, including extraction, purification as well as GC- and LC-based determination techniques. Much attention has been paid to OPEs because some of them are recognized highly toxic to biota, and the toxicological investigations of the most concerned OPEs were summarized. Risk assessments showed that the aquatic and benthic environments in some regions are under considerable ecological risks of OPEs. Finally, we pointed out problems in the current studies on OPEs and provided some suggestions for future research.

10.
Environ Sci Technol ; 53(23): 13551-13569, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31682424

RESUMO

Use of legacy brominated flame retardants (BFRs), including polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD), has been reduced due to adverse effects of these chemicals. Several novel brominated flame retardants (NBFRs), such decabromodiphenyl ethane (DBDPE) and bis(2,4,6-tribromophenoxy) ethane (BTBPE), have been developed as replacements for PBDEs. NBFRs are used in various industrial and consumer products, which leads to their ubiquitous occurrence in the environment. This article reviews occurrence and fate of a select group of NBFRs in the environment, as well as their human exposure and toxicity. Occurrence of NBFRs in both abiotic, including air, water, dust, soil, sediment and sludge, and biotic matrices, including bird, fish, and human serum, have been documented. Evidence regarding the degradation, including photodegradation, thermal degradation and biodegradation, and bioaccumulation and biomagnification of NBFRs is summarized. The toxicity data of NBFRs show that several NBFRs can cause adverse effects through different modes of action, such as hormone disruption, endocrine disruption, genotoxicity, and behavioral modification. The primary ecological risk assessment shows that most NBFRs exert no significant environmental risk, but it is worth noting that the result should be carefully used owing to the limited toxicity data.


Assuntos
Retardadores de Chama , Hidrocarbonetos Bromados , Animais , Poeira , Monitoramento Ambiental , Éteres Difenil Halogenados , Humanos , Esgotos
11.
Environ Res ; 178: 108732, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31541806

RESUMO

Several bisphenol analogues (BPs) are gradually replacing bisphenol A (BPA) in many fields, following strict restrictions on the production and use of BPA. The presence of micropollutants in wastewater treatment plants (WWTPs) may pose risks to the aquatic ecosystem and human health. In this review, we outlined the occurrence and fate of BPs in WWTPs, and estimated their potential risks to the aquatic ecosystem. BPA is still the most predominant bisphenol analogue in WWTPs with high detection rate and concentration, followed by bisphenol S (BPS) and F (BPF). Biodegradation and adsorption are the main removal pathways for removal of BPs in WWTPs. The secondary (activated sludge process, biological aerated filter, and membrane bioreactor) and advanced (membrane technique, ultraviolet disinfection, adsorption process, and ozonation) treatment processes show high removal efficiency for BPs, which are influenced by many factors such as sludge retention time and redox conditions. BPs other than BPA (assessed in this review) in effluent of WWTPs have low risks to Daphnia magna and early life stages on medaka, while BPA shows a medium or high risk under certain conditions. Knowledge gaps have been identified and future line of research on this class of chemicals in WWTPs is recommended. More data are needed to illustrate the occurrence and fate of BPs in WWTPs. Environmental risks of BPs other than BPA initiating from wastewater discharge to aquatic organisms remain largely unknown.


Assuntos
Compostos Benzidrílicos/análise , Monitoramento Ambiental , Fenóis/análise , Poluentes Químicos da Água/análise , Ecossistema , Humanos , Medição de Risco/estatística & dados numéricos , Águas Residuárias
12.
Environ Pollut ; 254(Pt A): 113020, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31421574

RESUMO

Increasing interest of seeking substitutable water resources accrues from shortage of freshwater. One of the options considered is reclaimed water (also designated as recycled water) that has been widely used in daily life. Although reclaimed water can serve as a feasible reliever of water pressure, attention about its technologies and potential risks is growing in the meantime. Most established wastewater treatment plants (WWTPs) predate many new contaminants, which means treatment processes cannot ensure to dislodge certain contaminants completely from origin water. Furthermore, a wide range of factors, such as seasons and influent variations, affect occurrence and concentration of reclaimed water-borne contaminants, making research about quality of reclaimed water especially significant. Many reclaimed water-borne contaminants, including biological and chemical contaminants, are toxic to human health, and complex wastewater matrix may aggravate water quality of concern. The widespread use of reclaimed water continues to be a concern on agriculture, ecological environment and human health. This study aims to: 1) provide a critical review about occurrence and profiles of diverse contaminants in the treated reclaimed water, 2) discuss the possibility to avoid the secondary pollution in reuse of reclaimed water, and 3) reveal the prospective consequences of using reclaimed water on agriculture, ecological environment and human health.


Assuntos
Eliminação de Resíduos Líquidos , Poluentes da Água/análise , Purificação da Água , Agricultura , Humanos , Estudos Prospectivos , Reciclagem , Águas Residuárias , Água , Qualidade da Água , Abastecimento de Água
13.
Talanta ; 197: 145-150, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30771916

RESUMO

We successfully developed a strategy to combine a customized gel electrophoresis device with ICP-MS for online separation and detection of metalloproteins. The self-designed horizontal column gel electrophoresis device was rapidly and easily fabricated in the laboratory via 3D printing with a low cost. The feasibility of 3D printing to fabricate this device was investigated by offline separation of commercial protein standards. And a better separation efficiency was found when using gel tubes printed with higher printing precision. As a proof-of-concept, the performance of the whole system is demonstrated by online separation and detection of both iodinated protein standards and proteins in rat blood plasma samples. Benefits from 3D printing, customized modification or further optimization can be readily achieved for a better protein separation and detection efficiency.


Assuntos
Metaloproteínas/análise , Impressão Tridimensional , Eletroforese , Espectrometria de Massas
14.
J Hazard Mater ; 363: 34-40, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30300776

RESUMO

Metal contaminants present persistent and deleterious threats to environmental ecosystems and human health. Microorganisms can rapidly develop protective mechanisms against metal toxicity, such as metallothionein production. The identification of biological factors related to these protective mechanisms is essential for effective metal remediation. This study presents a robust pathway to rapidly locate and characterize a Pb-binding flagellin in Serratia Se1998, which can bind Pb at a 16:1 Pb: protein ratio. A column gel electrophoresis system hyphenated with inductively coupled plasma mass spectrometry (ICP MS) was constructed to efficiently separate and identify Pb-binding proteins from the whole bacterial proteome. PCR and transgenic assays were used to elucidate the exact sequences and biological function of Pb-binding proteins and heterogeneous expression of Pb-binding flagellin in E. coli could significantly enhance Pb removal from aqueous solution by approximately 45%. This method provides a benchmark procedure to rapidly identify biological factors responsible for metal biosorption. Identification of this unique Pb-binding flagellin highlights that microorganisms can survive high metal stresses due to various complex biological pathways for metal detoxification and remediation.


Assuntos
Flagelina/química , Chumbo/química , Serratia/química , Sequência de Aminoácidos , Recuperação e Remediação Ambiental
15.
Sci Total Environ ; 628-629: 1489-1496, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30045567

RESUMO

The widespread use of organotin compounds (OTs) as biocides in antifouling paints and agricultural applications poses a serious threat to the ecosystem and humans. Butyltin compounds (BTs), especially tributyltin (TBT), are considered to be endocrine disrupting chemicals in marine organisms. The underlying mechanism of disrupting effects on mammals, however, has not been sufficiently investigated. To determine the effect and action of these biocides, the present study evaluated the effects of BTs on human adrenocortical carcinoma cells (H295R) with a focus on endocrine disrupting effect. Two-dimensional electrophoresis (2-DE) and subsequent mass finger printing were used to identify proteins expression profiles from the cells after exposure to 0.1µM BTs for 48h. In total, 89 protein spots showed altered expression in at least two treatment groups and 69 of these proteins were subsequently identified. Bioinformatic analysis of the proteins indicated that BTs involved in the regulation of hormone homeostasis, lipid metabolism, cell death, and energy production. IPA analysis revealed LXR/RXR (liver X receptor/retinoid X receptor) activation, FXR/RXR (farnesoid X receptor/retinoid X receptor) activation and fatty acid metabolism were the top three categories on which BTs acted and these systems play vital roles in sterol, glucose and lipid metabolism. The expression of LXR and FXR mRNA in H295R cells was stimulated by TBT, confirming the ability of TBT to activate this nuclear receptor. In summary, the differentially expressed proteins discovered in this study may participate in the toxic actions of BTs, and nuclear receptor activation and lipid metabolism may play important roles in such actions of BTs.


Assuntos
Disruptores Endócrinos/toxicidade , Compostos Orgânicos de Estanho/toxicidade , Proteoma/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Linhagem Celular Tumoral , Humanos , Proteômica , Compostos de Trialquitina
16.
Chemosphere ; 193: 1113-1119, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29874739

RESUMO

Silver sulfide nanoparticles (Ag2SNPs) have shown photocatalytic activity, yet little is known about the effect of Ag2SNPs on the photochemical degradation of dissolved organic matter (DOM) in surface water, which seriously impairs understanding of Ag2SNPs' environmental risks. Herein, this study on the basis of electrospray ionization coupled with Fourier-transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS) showed for the first time that photodegradation of natural organic matter (NOM, 2R101 N) could be accelerated by both bared and polyvinylpyrrolidone (PVP)-coated Ag2SNPs; the NOM with Ag2SNPs (e.g., 500 µg/L) exposed to light irradiation for 96 h showed molecular formulas with lower O/C ratios as compared to the NOM alone. Also, added number of points (ranging from 1 to 2 carboxyl groups) having the same Kendrick mass defect (KMD) (COO) values and higher intensity in smaller Kendrick mass (KM) (COO) values were observed in NOM with Ag2SNPs compared to NOM alone. However, negligible effects of Ag2SNPs on photodegradation of humic acid (HA, 2S101H) were observed, even when the concentration of Ag2SNPs was as high as 5 mg/L. Besides molecular characteristics, a great reduction in organic carbon content of NOM within 96 h was only observed in the presence of Ag2SNPs under light condition. More importantly, the enhanced photodegradation of DOM by Ag2SNPs even at a concentration of 100 µg/L was also validated in surface water. These findings suggest that Ag2SNPs have the potential to accelerate the photochemical degradation of DOM in surface water.


Assuntos
Nanopartículas/química , Fotoquímica/métodos , Compostos de Prata/química , Água/química
17.
Talanta ; 184: 404-410, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29674061

RESUMO

A two-dimensional (2-D, weak anion exchange chromatography-gel electrophoresis, WAX-GE) separations coupling to inductively coupled plasma mass spectrometry (ICP-MS) strategy was developed for efficient tracking of metalloproteins. Samples were fractionized with the primary dimension (WAX) and the collected fractions were subsequently subjected to the secondary dimension (GE) and finally detected with ICP-MS. The metalloproteins of interest from the secondary dimension were online split and collected for further manipulation. The molecular weight of metalloprotein was calibrated with a home-made protein marker including six iodine-labelled proteins with molecular weights ranging from 14 kDa to 77 kDa. The developed 2-D system is of higher separation resolution as compared to one-dimensional (1-D) system. Metalloproteins in Escherichia coli were further examined for validation of the method preformation. Several known or unknown metal-associated proteins were identified, evidencing the feasibility of the proposed method. Taken together, we established a solid methodology for efficient separation and qualitative study of metalloproteomics, providing a new strategy for the metallomics research.


Assuntos
Escherichia coli/química , Metaloproteínas/análise , Cromatografia por Troca Iônica , Eletroforese Capilar , Espectrometria de Massas
18.
Metallomics ; 10(4): 557-564, 2018 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-29637212

RESUMO

Silver nanoparticles (AgNPs) are the nanomaterials most widely used as antimicrobial agents in a range of consumer products, due to the environmental release of either the AgNPs themselves or silver ions. Although AgNPs appear to be more potent than silver ions, the mechanism behind the activity is not fully elucidated yet. The most common mechanism of toxicity of AgNPs proposed to date is the release of silver ions and/or the particle-specific functions. In this study, Pseudomonas aeruginosa (a model for Gram-negative bacteria) was treated with AgNPs, and its proteomic response was comprehensively characterized to elucidate the antimicrobial mechanism of AgNPs in the microorganism. In total, 59 silver-regulated proteins (27 up-regulated and 32 down-regulated proteins) and 5 silver-binding proteins were identified. Bioinformatic analysis revealed that interference with the cell-membrane function and generation of intracellular reactive oxygen species (ROS) were the main pathways for the antibacterial effect. The pattern of membrane proteins regulated by AgNPs was similar to that found for silver ions. In addition, the same silver-binding proteins were obtained with both AgNPs and silver ions, which indicated that AgNPs probably affect the cell membrane and react with proteins by releasing silver ions. The elevation of intracellular ROS relative to that with silver ions confirmed oxidative damage caused by AgNPs, which may be ascribed to the nano-characteristics and higher uptake efficiency of the particles. These results demonstrate that the antimicrobial activity of AgNPs is due to the synergistic action of release of dissolved silver ions and particle-specific effects. The proteomic analysis of silver-binding and silver-regulated proteins in the present study provides insight into the mechanism of antimicrobial activity of such nanomaterials.


Assuntos
Antibacterianos/administração & dosagem , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Nanopartículas Metálicas/administração & dosagem , Proteômica/métodos , Pseudomonas aeruginosa/metabolismo , Prata/química , Antibacterianos/química , Nanopartículas Metálicas/química , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Espécies Reativas de Oxigênio/metabolismo
19.
Ecotoxicol Environ Saf ; 156: 148-153, 2018 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-29549738

RESUMO

Organotin compounds (OTs) are used in a range of industrial products, such as antifouling paints, agricultural pesticides and stabilizers. Owing to potential endocrine-disrupting effects, human exposure to such compounds is a concern. Nevertheless, little is known about the adverse effect of OTs on adrenocortical function in organisms. In this study, the human adrenocortical carcinoma cell (H295R) model was used to investigate effects of OTs on steroidogenesis and potential causes for such endocrine disruption was examined. H295R cells were exposed to several commonly used OTs, including triphenyltin (TPT), tributyltin (TBT), dibutyltin (DBT), and monobutyltin (MBT), and the production level of steroid hormones were quantified. TPT and TBT decreased the production levels of 17ß-estradiol, aldosterone, and cortisol, but increased that of testosterone. Furthermore, the expression levels of ten major steroidogenic genes (HMGR, StAR, CYP11A1, 3ßHSD2, CYP17, CYP19A1, CYP21, CYP11B1, CYP11B2, and 17ßHSD) were examined and both up-regulation of CYP11B2 and down-regulation of StAR, 3ßHSD2, CYP19A1, CYP21 and CYP11B1 by TPT and TBT were observed. Intracellular levels of ATP and cyclic adenosine monophosphate (cAMP) and the activity of adenylate cyclase (AC) decreased in the H295R cells treated with TPT and TBT. No obvious changes in H295R were found with the treatment of DBT and MBT. These results suggest that OTs may stimulate steroidogenesis in vitro via inhibition of cAMP signaling pathway.


Assuntos
AMP Cíclico/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Compostos Orgânicos de Estanho/toxicidade , Praguicidas/toxicidade , Proteínas/metabolismo , Adenilil Ciclases/genética , Adenilil Ciclases/metabolismo , Linhagem Celular Tumoral , AMP Cíclico/genética , Sistema Enzimático do Citocromo P-450/genética , Disruptores Endócrinos/toxicidade , Estradiol/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Hidrocortisona/metabolismo , Proteínas/genética , Transdução de Sinais , Esteroides/metabolismo , Testosterona/metabolismo
20.
Sensors (Basel) ; 18(1)2018 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-29301369

RESUMO

The water source, as a significant body of the earth, with a high value, serves as a hot topic to study Underwater Sensor Networks (UWSNs). Various applications can be realized based on UWSNs. Our paper mainly concentrates on the localization algorithms based on the acoustic communication for UWSNs. An in-depth survey of localization algorithms is provided for UWSNs. We first introduce the acoustic communication, network architecture, and routing technique in UWSNs. The localization algorithms are classified into five aspects, namely, computation algorithm, spatial coverage, range measurement, the state of the nodes and communication between nodes that are different from all other survey papers. Moreover, we collect a lot of pioneering papers, and a comprehensive comparison is made. In addition, some challenges and open issues are raised in our paper.

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