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The increasing presence of arsenic-containing impurities within Cu ores can adversely affect the smelting process and aggravate the environmental impact of slag tailing. This study investigates the geochemical, mineralogical, and chemical speciation characteristics to better understand the association and environmental stability of metal(loid)s in copper slag tailing. The results indicate that the predominant chemical compositions of the selected slag tailing are Fe2O3 (54.8%) and SiO2 (28.1%). These tailings exhibit potential for multi-elemental contamination due to elevated concentrations of environmentally sensitive elements. Mineral phases identified within the slag tailings include silicate (fayalite), oxides (magnetite and hematite), and sulfides (galena, sphalerite, arsenopyrite, and chalcopyrite). The consistent presence of silicate, iron, arsenic, and oxygen in the elemental distribution suggests the existence of arsenic within silicate minerals in the form of Si-Fe-As-O phases. Additionally, arsenic shows association with sulfide minerals and oxides. The percentages of arsenite (As(III)) and arsenate (As(V)) within the selected slag tailings are 59.4% and 40.6%, respectively. While the slag tailings are deemed non-hazardous due to the minimal amounts of toxic elements in leachates, proper disposal measures should be taken due to the elevated carbonate-bound levels of As and Cu present in these tailings.
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Industrial by-products are stored in large quantities in the open, leading to wasted resources and environmental pollution, and the natural environment is similarly faced with phosphate depletion and serious water and soil pollution. This study uses these by-products to produce a new sludge/biomass ash ceramsite that will be used to adsorb nitrogen and phosphorus from wastewater, and solidify heavy metals in the soil while releasing Olsen P. The sludge/biomass ash ceramsites are made using sewage sludge and biomass ash in a certain ratio calcined at high temperatures and modified for the adsorption of nitrogen and phosphorus from wastewater. Sludge/biomass ash ceramsites before and after phosphorus adsorption, biochar and biomass ash were compared to analyze their heavy metal adsorption capacity and potential as phosphate fertilizer. After phosphorus adsorption, the sludge/biomass ash ceramsites released effective phosphorus steadily and rapidly in the soil, with a greater initial release than biochar and biomass ash, and the ceramsites were in a granular form that could be easily recycled. Biochar and biomass residue, due to their surface functional groups, are better at solidifying heavy metals than sludge/biomass ash ceramsites. Biochar, biomass ash and sludge/biomass ash ceramsites significantly reduced the concentrations of Cd, Cu, Pb and Zn in the soil. Correlation analysis demonstrated that there was a synergistic relationship between the increase in soil Olsen P content and the change in pH, with the increase in soil Olsen P content and the increase in pH contributing to heavy metal solidification.
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Misturas Complexas , Metais Pesados , Poluentes do Solo , Esgotos/química , Águas Residuárias , Biomassa , Metais Pesados/análise , Carvão Vegetal/química , Solo/química , Fósforo/análise , Fosfatos/análise , Nitrogênio/análise , Poluentes do Solo/análiseRESUMO
It is possible to achieve high-value utilization of solid wastes and lower the cost of mesoporous silica synthesis by synthesizing mesoporous silica from solid wastes. In this study, silica was extracted using the alkali fusion method using biomass ash as the starting material. Biomass ash based mesoporous silica was successfully prepared by hydrothermal method with silicon extract solution as silicon source. The optimum conditions for preparation were determined as follows: addition of cetyltrimethylammonium bromide was 0.45g, hydrothermal temperature was 120 °C, hydrothermal time was 24h. The prepared mesoporous silicon was systematically characterized, and the results showed that high surface area (495 m2/g) and ordered pore structure appeared in the synthesized mesoporous silica materials. The synthesized mesoporous silica showed excellent CO2 adsorption performance (0.749 mmol/g) at 25 °C and 1 bar. According to the calculation of adsorption isotherm and thermodynamics, non-linear Freundlich model can fit the adsorption isotherm better and the adsorption heat of mesoporous silica is less than 20 kJ/mol, which belongs to physical adsorption. After five cycles of CO2 adsorption, the adsorption property was still above 90%, and the CO2/N2 adsorption selectivity reached 396.6, showing good regeneration performance and adsorption selectivity. This research can provide a new possibility for the high-value exploitation of biomass ash and reducing the cost of synthetic mesoporous silica.
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Dióxido de Silício , Resíduos Sólidos , Dióxido de Silício/química , Dióxido de Carbono/química , Silício , Adsorção , BiomassaRESUMO
The numerous resources are consumed and a large number of multiple-source organic solid wastes are discharged during urban metabolic, which put pressures to environment. This study combined material flow analysis and ecological network analysis to comprehensively analyse the metabolism of multiple-source organic solid waste in Hefei. Analysing current metabolic characteristics of urban multiple-source organic solid waste and relationships between the components of metabolic system can help urban environmental management. The internal material flows of the system were analysed by a metabolic network containing 5 nodes and 18 pathways, which revealed metabolic characteristics of multiple-source organic solid waste in Hefei. The study showed that the metabolic system of multiple-source organic solid waste was relatively stable though distribution of internal flows changed in 8 years. The metabolic environment and agricultural sector covered a relatively large weight in this model. The control and exploitation relationships dominated the metabolic system. The urban metabolic mechanism reflected in this research can improve efficiency of urban metabolic resource, optimize waste management and provide data support for sustainable urban development. This study provided scientific guidance for metabolic research in Hefei and similar cities in China's rapid economic development.
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Resíduos Sólidos , Gerenciamento de Resíduos , Resíduos Sólidos/análise , Agricultura , Cidades , ChinaRESUMO
The increasing requirement and consumption of coal has resulted in a large accumulation of coal gangue. The reuse and recycling of coal gangue have become a high priority for sustainable development. A sustainable and efficient ceramsite adsorbent was prepared for copper ions adsorption by using coal gangue, coal fly ash, and copper slag as the main materials. The appropriate performance of the ceramsite could be obtained at a mixture of coal gangue, coal fly ash, and copper slag at a weight ratio of 3:4:1. The optimal sintering temperature and time were 1050 °C and 20 min, respectively. The main crystalline phases of ceramsite were quartz, mullite, and anorthite. Many micropores are connecting the interior on the surface of ceramsite under scanning electron microscope. The maximum copper ions adsorption capacity reached up to 20.6 mg/g at 303 K when pH and time were 5 and 1440 min, respectively. The adsorption kinetics and isotherm could be described by the pseudo-second-order model and Freundlich model, respectively. The adsorption mechanisms of Cu2+ with ceramsite were attributed to Cu(OH)2 precipitation formed on the alkaline surface of ceramsite and complexation reactions occurred between the O-containing groups (including C-O, Fe-O, and Si-O) from ceramsite and Cu2+. The prepared ceramsite may be also applied to other heavy metal wastewater treatments.
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Resíduos Industriais , Poluentes Químicos da Água , Adsorção , Carvão Mineral , Cinza de Carvão , Misturas Complexas , Cobre , Íons , CinéticaRESUMO
Both the accumulation of coal gangue and potentially toxic elements in aqueous solution have caused biological damage to the surrounding ecosystem of the Huainan coal mining field. In this study, coal gangue was used to synthesize calcium silicate hydrate (C-S-H) to remove Cr(VI) and Cu(II)from aqueous solutions and aqueous solution. The optimum parameters for C-S-H synthesis were 700 °C for 1 h and a Ca/Si molar ratio of 1.0. Quantitative sorption analysis was done at variable temperature, C-S-H dosages, solution pH, initial concentrations of metals, and reaction time. The solution pH was precisely controlled by a pH meter. The adsorption temperature was controlled by a thermostatic gas bath oscillator. The error of solution temperature was controlled at ± 0.3, compared with the adsorption temperature. For Cr(VI) and Cu(II), the optimum initial concentration, temperature, and reaction time were 200 mg/L, 40 °C and 90 min, pH 2 and 0.1 g C-S-H for Cr(VI), pH 6 and 0.07 g C-S-H for Cu(II), respectively. The maximum adsorption capacities of Cr(VI) and Cu(II) were 68.03 and 70.42 mg·g-1, respectively. Furthermore, the concentrations of Cu(II) and Cr(VI) in aqueous solution could meet the surface water quality standards in China. The adsorption mechanism of Cu(II) and Cr(VI) onto C-S-H were reduction, electrostatic interaction, chelation interaction, and surface complexation. It was found that C-S-H is an environmentally friendly adsorbent for effective removal of metals from aqueous solution through different mechanisms.
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The distribution characteristics of Cadmium (Cd) fractions in soils around a coal mining area of Huaibei coalfield were investigated, with the aim to assess its ecological risk. The total Cd concentrations in soils ranged from 0.05 to 0.87â¯mg/kg. The high percentage of phyto-available Cd (58%) when redox or base-acid equilibria changed. Soil pH was found to be a crucial factor affecting soil Cd fraction, and carbonate-bound Cd can be significantly affected by both organic matter and pH of soils. The static ecological evaluation models, including potential ecological risk index (PERI), geo-accumulation index (Igeo) and risk assessment code (RAC), revealed a moderate soil Cd contamination and prensented high Cd exposure risk in studied soils. However, the dynamic evaluation of Cd risk, determined using a delayed geochemical hazard (DGH), suggested that our studied soils can be classified as median-risk with a mean probability of 24.79% for Cd DGH. These results provide a better assessment for the risk development of Cd contamination in coal mining areas.
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Cádmio/análise , Poluentes do Solo/análise , Cádmio/química , Carbonatos/química , China , Minas de Carvão , Ecossistema , Monitoramento Ambiental , Medição de Risco , Poluentes do Solo/químicaRESUMO
A series of amphiphilic diblock copolypeptides (K30 -b-F15 , K30 -b-F30 , and K30 -b-F45 ) were synthesized via N-carboxy-α-amino-anhydride ring-opening polymerization. The copolypeptides had excellent antibacterial efficacy to both Gram positive (S. aureus) and Gram negative (E. coli) bacteria. The minimum inhibitory concentrations (MICs) against E. coli and S. aureus are 8 µg mL-1 and 2 µg mL-1 , respectively, lower than most natural and artificial antimicrobial peptides (AMPs). The morphological changes of the bacteria treated with diblock copolypeptides were investigated by transmission electron microscopy; the results proved that the diblock copolypeptides had a similar antibacterial pore-forming mechanism to natural cationic peptides. This was confirmed by laser scanning confocal microscope images. CCK-8 results and the MICs showed that the diblock copolypeptides have high selectivity to bacteria, which suggested that the diblock copolypeptides could be excellent candidates to replace traditional antibiotics in future.
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Antibacterianos/farmacologia , Peptídeos/química , Peptídeos/farmacologia , Antibacterianos/efeitos adversos , Antibacterianos/química , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos/métodos , Escherichia coli/efeitos dos fármacos , Humanos , Lisina/química , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Peptídeos/síntese química , Fenilalanina/química , Pseudomonas aeruginosa/efeitos dos fármacos , Serratia marcescens/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacosRESUMO
It is an important challenge for bone repair to effectively deliver growth factors and at the same time to prevent and cure inflammation without obvious pathogen resistance. We designed a kind of antibacterial peptide-mimetic alternating copolymers (PMACs) to effectively inhibit and kill both Gram-positive and Gram-negative bacteria. The minimum inhibition concentrations (MICs) of the PMACs against E. coli and S. aureus are 8.0 µg/mL, which are much lower than that of antibacterial peptides synthesized by other methods such as widely used ring-opening polymerization of N-carboxyanhydride. Furthermore, the PMACs can self-assemble into polymer vesicles (polymersomes) in pure water with low cytotoxicity (IC50 > 1000 µg/mL), which can encapsulate growth factors in aqueous solution and release them during long-term antibacterial process for facilitating bone repair. We also find that the alternating structure is essential for the excellent antibacterial activity. The in vivo tests in rabbits confirmed that the growth-factor-encapsulated antibacterial vesicles have better bone repair ability compared with control groups without antibacterial vesicles. Overall, we have provided a novel method for designing PMAC-based highly effective intrinsically antibacterial vesicles that may have promising biomedical applications in the future.
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Antibacterianos/farmacologia , Osso e Ossos/efeitos dos fármacos , Peptídeos/farmacologia , Polímeros/química , Antibacterianos/química , Osso e Ossos/metabolismo , Linhagem Celular , Escherichia coli/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Testes de Sensibilidade Microbiana/métodos , Peptídeos/química , Polimerização/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacosRESUMO
Cancer patients after chemotherapy may also suffer bacterial attack due to badly decreased immunity. Although with high bacterial efficacy, conventional antibiotics are prone to inducement of drug resistance and may be not suitable for some cancer patients. In contrast, antibacterial peptides are highly effective in inhibiting bacteria without inducing resistance in pathogens. Presented in this article is a novel kind of highly effective antibacterial peptide-based biocompatible and biodegradable block copolymer vesicle. The copolymer is poly(ε-caprolactone)-block-poly[phenylalanine-stat-lysine-stat-(lysine-folic acid)] [PCL19-b-poly[Phe12-stat-Lys9-stat-(Lys-FA)6]], which can self-assemble into vesicles in aqueous solution. The biocompatible and biodegradable PCL forms the vesicle membrane, whereas the poly[Phe12-stat-Lys9-stat-(Lys-FA)6] block constitutes the vesicle coronas. Compared to the individual polymer chains, the vesicles showed enhanced antibacterial activities against both Gram-positive and Gram-negative bacteria (16 µg mL(-1)) due to the locally concentrated antibacterial poly[Phe12-stat-Lys9-stat-(Lys-FA)6] coronas, which may avoid the inducement of antibiotic-resistant bacteria and side effects of multidrug interactions. Furthermore, folic acid is introduced into the vesicle coronas for potential further applications such as cancer-targeted drug delivery. Moreover, the amino groups can be further functionalized when necessary. This low cytotoxic, biocompatible, biodegradable, and antibacterial vesicle (without antibiotic resistance) may benefit patients after tumor surgery because it is highly anti-inflammatory, and it is possible to deliver the anticancer drug to tumor cells simultaneously.
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Antibacterianos/síntese química , Peptídeos Catiônicos Antimicrobianos/química , Portadores de Fármacos/síntese química , Ácido Fólico/química , Poliésteres/química , Antibacterianos/farmacologia , Antibióticos Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Materiais Biocompatíveis , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/farmacologia , Portadores de Fármacos/farmacologia , Liberação Controlada de Fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Humanos , Cinética , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Propriedades de SuperfícieRESUMO
Heavy metal accumulation in agricultural soil is of great concern, as heavy metals can be finally transferred to the human body through the food chain. A field survey was conducted to investigate the lead (Pb) levels and distribution in soil, agricultural products (wheat, paddy, and soybean), and fish, in the Huainan Coal Mining Area (HCMA), Anhui Province, China, to provide reference information to local inhabitants. The daily intake and target hazard quotients of Pb through food consumption were assessed. Results showed that the mean Pb concentration in soil was higher than the Huainan soil background Pb value but lower than the maximum allowance Pb concentration for agricultural soil (GB 15618-2008). The elevated Pb in soil, especially in rainy months (June to August in Huainan), might be related to Pb leaching from ambient coal gangue piles. Excessive Pb concentration was found in the grains of food crops, which would pose a potential health risk to local inhabitants. Therein, wheat showed higher Pb bioaccumulation ability than other crops. With regard to the Pb levels in muscles, fishes were considered to be safe for consumption. The calculations on daily intake and tolerable hazard quotient of Pb suggest that the potential health hazard posed by Pb is currently insignificant for the inhabitants in the HCMA.
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Minas de Carvão , Produtos Agrícolas/química , Monitoramento Ambiental , Chumbo/análise , Solo/química , Agricultura , China , Carvão Mineral , Grão Comestível , Saúde , Humanos , Metais Pesados/análise , Poluentes do Solo/análise , TriticumRESUMO
Lead (Pb) has gained much attention since the 1970s because of its potential and cumulative toxicity. As one of the most hazardous elements in coals, Pb can be released into the environment during coal mining, processing, and utilization. This study presents a synthesis on the abundance, distribution, modes of occurrence, and environmental impacts of Pb in Chinese coals. Using the expected coal reserves as the weighting factor and based on the previously published Pb content in 4,304 coal samples (including results obtained in our laboratory) from main coalfields or coal mines in China, the weighted mean Pb content in Chinese coals is 13.0 µg/g, which is higher than that of the American coals (11 µg/g) and average world coals (7.8 µg/g). With respect to regional distribution of Pb in Chinese coals, Pb content can be arbitrarily divided into three groups (<20, 20-40, >40 µg/g). Following this classification, coals from Tibet have the highest average Pb content (128.94 µg/g). The abundance of Pb in coals varies with coal-forming periods and coal ranks, with the late Triassic and higher rank coals having the highest Pb content, which could be ascribed to regional geochemical differences and later geological evolution as well as magma hydrothermal activities. The enrichment of Pb in coals is influenced by several geological factors, including coal-forming plants, source rocks, hydrothermal fluid, and depositional environment. Pb, dominantly associates with sulfide minerals, especially galena in coals. During coal combustion or pyrolysis, Pb is partly emitted into the atmosphere and partly partitioned to solid residues. Accumulation of Pb from coal utilization in human body could lead to a range of health problems and increase the risk of cancer.
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Carvão Mineral/análise , Poluentes Ambientais/análise , Chumbo/análise , China , Poluentes Ambientais/farmacocinética , Humanos , Chumbo/farmacocinéticaRESUMO
Coal is one of the major energy resources in China, accounting for approximately 70 % of primary energy consumption. Many environmental problems and human health risks arise during coal exploitation, utilization, and waste disposal, especially in the remote mountainous areas of western China (e.g., eastern Yunnan, western Guizhou and Hubei, and southern Shaanxi). In this paper, we report a thorough review of the environmental and human health impacts related to coal utilization in China. The abundance of the toxic trace elements such as F, As, Se, and Hg in Chinese coals is summarized. The environmental problems (i.e., water, soil, and air pollution) that are related to coal utilization are outlined. The provenance, distributions, typical symptoms, sources, and possible pathways of endemic fluorosis, arsenism, and selenosis due to improper coal usage (briquettes mixed with high-F clay, mineralized As-rich coal, and Se-rich stone coal) are discussed in detail. In 2010, 14.8, 1.9 million, and 16,000 Chinese people suffered from dental fluorosis, skeletal fluorosis, and arsenism, respectively. Finally, several suggestions are proposed for the prevention and treatment for endemic problems caused by coal utilization.
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Carvão Mineral , Meio Ambiente , Exposição Ambiental/efeitos adversos , Saúde Pública , Arsênio/toxicidade , Intoxicação por Arsênico/etiologia , China , Carvão Mineral/análise , Flúor/toxicidade , Fluorose Dentária/etiologia , Humanos , Mercúrio/toxicidade , Selênio/toxicidade , Poluentes do Solo/análise , Poluição da ÁguaRESUMO
Coal mining area is highly subject to lead (Pb) pollution from coal mining activities. Several decades of coal mining and processing practices in dozens of coal mines in the Huainan Coal Mining Area (HCMA) have led to the accumulation of massive amounts of coal gangue, which piled in dumps. In order to investigate the impacts of coal gangue dumps on Pb level in the supergene media of the HCMA, a systematic sampling campaign comprising coal gangue, soil, wheat, and earthworm samples was conducted. The average Pb content in the coal mining area soil is 24 mg/kg, which is slightly higher than the associated coal gangues (23 mg/kg) and markedly higher than reference region soil (12.6 mg/kg). Soil in the HCMA present a slight to moderate Pb contamination, which might be related to the weathering and leaching of coal gangue dumps. Lateral distribution of Pb in HCMA soil differed among individual coal mines. The soil profile distribution of Pb depends on both natural and anthropogenic contributions. Average Pb content is higher in roots than in stems, leaves, and wheat husks, while the Pb level in seeds exceeded the maximum Pb allowance for foods (Maximum Levels of Contaminants in Foods of China, GB 2762-2012). Earthworms in the selected area are significantly enriched in Pb, suggesting higher bio-available Pb level in soil in the HCMA.
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Minas de Carvão , Monitoramento Ambiental , Chumbo/análise , Poluentes do Solo/análise , China , Poluição Ambiental/estatística & dados numéricos , Resíduos Industriais/análise , Resíduos Industriais/estatística & dados numéricos , Solo/químicaRESUMO
The waste slag known as jarosite residue (JR) and arsenic sulfide residue (ASR) were produced following the creation of zinc by hydrometallurgical procedures. The increasing annual zinc mining has led to growing pressure to dispose of the resulting JR and ASR from zinc smelting, making it crucial to assess their environmental impact and feasibility for utilization. The main components, distribution characteristics of elements, and potential environmental risks of zinc smelting wastes are studied through toxicity leaching tests, sequential extraction procedures, and various characterization technologies such as XRF, XRD, and SEM-EDS. The mineral compositions of JR are natrojarosite, franklinite, and gunningite, and zinc mainly adheres to the crevices of the natrojarosite mineral. Meanwhile, the ASR of flocculent structures is composed of orpiment, greenockite, arsenic oxide, and calvertite, and As appears in the form of the S-As-O phase. The Zn, Cu, and Cd in JR were dominated by exchangeable bound (81.53-96.6 %), and the main form of As, Cd, Se, and Tl in ASR was organic matter bound (87.0-99.21 %). The Risk Assessment Code (RAC) method confirmed the risk of Cd, Cu, Zn, and Mo in JR is high, while the risk of Cd, Pb, and Cr in ASR is moderate. Compared to the standard value of "Identification Standard for Toxicity of Hazardous Waste Leaching (GB5085.3-2007)", the leachate concentrations of Zn in JR as well as Cd and As in ASR were exceeded, suggesting that the JR and ASR were in the type of hazardous waste and posed an environmental risk. The study provides theoretical guidance for the future rational management and effective utilization of hazardous waste.
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The increasing severity of problems posed by drug-resistant pathogens has compelled researchers to explore innovative approaches for infection prevention. Among these strategies, conjugation methods stand out for their convenience and high efficacy. In this study, multiple covalent conjugates were synthesized, incorporating the natural antimicrobial peptide epsilon-poly-l-lysine (EPL) and two commonly used ß-lactam antibiotics: penicillin G or ampicillin. Enhanced antimicrobial efficacy against typical Gram-negative pathogens, along with faster kill kinetics compared to combination approaches, was demonstrated by the EPL-Ampicillin covalent conjugates. Their antimicrobial mechanism was also substantiated through SEM and fluorescence tests in this work, confirming the inheritance of membrane-disrupting properties from EPL. Furthermore, the excellent biocompatibility of the raw materials was reserved in the covalent conjugates. This simplified conjugation method holds promise for the development of infection therapeutic drugs and potentially restores the sensitivity of conventional antibiotics to drug-resistant pathogens by introducing membrane-disrupting mechanisms.
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Polilisina , Antibióticos beta Lactam , Polilisina/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Ampicilina/farmacologia , Penicilina G , MonobactamasRESUMO
Most of the existing research for heavy metals in water at present is focusing on surface water. However, potential environmental risk of heavy metals in the bottom water of lakes cannot be ignored. In this study, the content, distribution, and speciation of nine heavy metals (As, V, Cr, Co, Ni, Cu, Zn, Cd, and Pb) in the bottom water and sediment of Chaohu Lake were studied. Some pollution assessment methods were used to evaluate the environmental effect of heavy metals. Positive matrix factorization was conducted to investigate the potential sources of heavy metals in sediment. The contents of heavy metals in the bottom water of Chaohu Lake mean that its environmental pollution can be ignored. In sediment, Cd and Zn have showed stronger ecological risk. pH and redox potential are more likely to affect the stability of heavy metals in the bottom water of Chaohu Lake during the dry reason. Industrial sources (16%) are no longer the largest source of heavy metal pollution; traffic sources (33.6%) and agricultural sources (23.4%) have become the main sources of pollution at present. This study can provide some support and suggestions for the treatment of heavy metals in lakes.
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Metais Pesados , Poluentes Químicos da Água , Cádmio , Lagos/química , Água , Sedimentos Geológicos/química , Monitoramento Ambiental , Metais Pesados/análise , Poluição Ambiental , Poluentes Químicos da Água/análise , China , Medição de RiscoRESUMO
Bacteria in tumor microenvironments promote carcinogenesis and trigger complications, suggesting the significance of intervening in bacterial growth in cancer treatment. Here, dendrimer-derived mimics (DMs) of host defense peptides (HDPs) were designed for antibacterial and anticancer therapy, which feature a dendronized polylysine core and polycaprolactone arms. DMs displayed not only remarkable activities against Staphylococcus aureus and human lung cancer cells, but also exceptional selectivity. The membranolytic mechanism revealed by morphology analysis explained their low susceptibility to induce resistance. Further, the optimized DM inhibited tumor growth in the subcutaneous tumor model when administered via intraperitoneal injection and exhibited negligible toxicity to tissues. Overall, we combined the superiority of dendrimers and the mechanism from HDPs to design agents with dual antibacterial and anticancer activities that possess great potential for clinical oncology therapy.
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Antibacterianos , Antineoplásicos , Dendrímeros , Polilisina , Staphylococcus aureus , Humanos , Dendrímeros/química , Dendrímeros/farmacologia , Dendrímeros/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/química , Polilisina/química , Polilisina/farmacologia , Polilisina/uso terapêutico , Staphylococcus aureus/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Camundongos , Testes de Sensibilidade Microbiana , Linhagem Celular Tumoral , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Peptídeos Catiônicos Antimicrobianos/química , Poliésteres/química , Poliésteres/farmacologiaRESUMO
The trace metal pollution of sediments in Chaohu Lake, one of the most highly eutrophic lakes in East China, was investigated. Surface sediment (0-5 cm) samples were collected from 35 different positions and analyzed by inductively coupled plasma optical emission spectrometry to determine trace metal contents. Results showed that the mean content of trace metals was as follows: Cr, 85.09 mg kg(-1); Cu, 34.49 mg kg(-1); Ni, 26.46 mg kg(-1); Pb, 34.17 mg kg(-1) and Zn, 107.46 mg kg(-1). The trace metal concentrations from different sampling sites displayed spatial diversity; the heavily polluted sampling sites were close to where estuaries flow in to the lake. A four-step sequential extraction was used to examine the partitioning of the trace metals. Results demonstrated that the percentage of the species bound to the oxidizable phase for all trace metals ranged from 15.6 to 37.7%, while for Cu, Cr and Ni, the main forms were residual (41.3, 62.3 and 69.8%, respectively). Trace metals in the oxidizable fraction may mainly exist in the form of sulfides. The ecological potential risks of trace metals decreased as follows: Pb > Zn > Cu > Cr > Ni.
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Sedimentos Geológicos/análise , Metais Pesados/análise , Poluentes Químicos da Água/análise , Adsorção , China , Monitoramento Ambiental , Sedimentos Geológicos/química , Lagos , Metais Pesados/química , Poluentes Químicos da Água/químicaRESUMO
The rapid expansion of biomass power generation has resulted in a large amount of ash, which need to be treated urgently. The trace elements in ash also have environmental risks during treatment. Therefore, the essential characteristics and potential environmental risks of biomass ash generated by direct combustion of agricultural straw were studied. The leaching characteristics of elements, including major elements (Mg, K, Ca) and trace elements (V, Cr, Mn, Co, Ni, Cu, Zn, Cd, As, Pb and Ba), in fly ash and slag produced by biomass power plant were analyzed through the static leaching experiments of simulating the possible pH value of natural water in the laboratory. The results show that the trace elements are enriched in fly ash and slag, which may be related to the volatility of elements during combustion. And during the leaching test, the leaching concentration of major and trace elements in fly ash is higher than that in slag. Sequential chemical extraction is used to reveal the occurrence forms of trace elements in biomass ash. Except for residue, Mn, Co, Zn, Cd, and Pb in fly ash mainly exist in carbonate bound, V and As are Fe-Mn oxides bound, and Cr, Ni, Cu, and Ba are mainly organic matter bound. In the slag, Cd is mainly carbonate bound, Cu is mainly organic matter bound, while other elements are mainly Fe-Mn oxides bound. The Risk Assessment Code values calculated based on the existing forms of elements show that As and Cd in slag and Mn, Co, Pb and Cd in fly ash need special attention during utilization. The research results can provide reference for the management and utilization of biomass ash.