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[PMID]:28735237
[Au] Autor:Kim B; Ji K; Kho Y; Kim PG; Park K; Kim K; Kim Y; Kim KT; Choi K
[Ad] Endereço:Department of Environmental Health, Graduate School at Yongin University, Yongin, 17092, Republic of Korea.
[Ti] Título:Effects of chronic exposure to cefadroxil and cefradine on Daphnia magna and Oryzias latipes.
[So] Source:Chemosphere;185:844-851, 2017 Oct.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Cefadroxil and cefradine have frequently been detected in surface waters, however toxicological studies in aquatic organisms have mostly been limited to acute lethal effects. In the present study, endocrine disruption caused by cefadroxil and cefradine, and its underlying mechanism were investigated by chronic exposure of Daphnia magna (21 d) and Oryzias latipes (120 d). In medaka fish, the effects on growth, mortality, and reproduction, as well as on the levels of hormones and genes related to the hypothalamic-pituitary-gonad (HPG) axis, were investigated after 120 d exposure. In D. magna, the chronic effects on growth were observed at the highest concentration of 83.0 mg L cefadroxil and 80.8 mg L cefradine. The growth of juvenile fish was significantly impaired by exposure to cefradine. Following exposure to cefadroxil and cefradine for 120 d, sex-dependent changes in E2 hormones were observed and their levels were supported by the regulation of genes along the HPG axis. We found that chronic exposure to cefadroxil and cefradine impaired growth and reproduction in a freshwater invertebrate and fish, and altered the levels of sex hormones and genes associated with the HPG axis in fish.
[Mh] Termos MeSH primário: Cefadroxila/toxicidade
Cefradina/toxicidade
Poluentes Químicos da Água/toxicidade
[Mh] Termos MeSH secundário: Animais
Daphnia/efeitos dos fármacos
Disruptores Endócrinos/toxicidade
Sistema Endócrino/efeitos dos fármacos
Água Doce
Hormônios Esteroides Gonadais
Masculino
Oryzias/fisiologia
Reprodução/efeitos dos fármacos
Testes de Toxicidade Crônica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Endocrine Disruptors); 0 (Gonadal Steroid Hormones); 0 (Water Pollutants, Chemical); 280111G160 (Cefadroxil); F1BC02I72W (Cephradine)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170724
[St] Status:MEDLINE


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[PMID]:26564987
[Au] Autor:Khandelwal P; Singh DK; Sadhu S; Poddar P
[Ad] Endereço:Physical & Material Chemistry Division, CSIR-National Chemical Laboratory, Pune-411008, India. p.poddar@ncl.res.in.
[Ti] Título:Study of the nucleation and growth of antibiotic labeled Au NPs and blue luminescent Au8 quantum clusters for Hg(2+) ion sensing, cellular imaging and antibacterial applications.
[So] Source:Nanoscale;7(47):19985-20002, 2015 Dec 21.
[Is] ISSN:2040-3372
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Herein, we report a detailed experimental study supported by DFT calculations to understand the mechanism behind the synthesis of cefradine (CFD--an antibiotic) labeled gold nanoparticles (Au NPs) by employing CFD as both a mild reducing and capping agent. The analysis of the effect of growth conditions reveals that a higher concentration of HAuCl4 results in the formation of an increasing fraction of anisotropic structures, higher temperature leads to the formation of quasi-spherical particles instead of anisotropic ones, and larger pH leads to the formation of much smaller particles. The cyclic voltammetry (CV) results show that when the pH of the reaction medium increases from 4 to 6, the reduction potential of CFD increases which leads to the synthesis of nanoparticles (in a pH 4 reaction) to quantum clusters (in a pH 6 reaction). The MALDI-TOF mass spectrometry results of supernatant of the pH 6 reaction indicate the formation of [Au8(CFD)2S6] QCs which show fluorescence at ca. 432 nm with a Stokes shift of ca. 95 nm. The blue luminescence from Au8 QCs was applied for sensing of Hg(2+) ions on the basis of an aggregation-induced fluorescence quenching mechanism and offers good selectivity and a high sensitivity with a limit of detection ca. 2 nM which is lower than the detection requirement of 10 nM by the U.S. EPA and 30 nM by WHO for drinking water. We have also applied the sensing probe to detect Hg(2+) ions in bacterial samples. Further, we have investigated the antibacterial property of as-synthesized Au NPs using MIC, growth curve and cell survival assay. The results show that Au NPs could reduce the cell survival very efficiently rather than the cell growth in comparison to the antibiotic itself. The scanning electron microscopy study shows the degradation and blebbing of the bacterial cell wall upon exposure with Au NPs which was further supported by fluorescence microscopy results. These Au NPs did not show reactive oxygen species generation. We believe that the bacterial cytotoxicity is due to the direct contact of the Au NPs with bacterial cells.
[Mh] Termos MeSH primário: Antibacterianos/química
Ouro/química
Mercúrio/química
Nanopartículas Metálicas/química
[Mh] Termos MeSH secundário: Acetatos/química
Anisotropia
Proliferação Celular
Sobrevivência Celular
Cefradina/química
Concentração de Íons de Hidrogênio
Íons
Luminescência
Microscopia Eletrônica de Varredura
Microscopia de Fluorescência
Nanotecnologia/métodos
Estresse Oxidativo
Pontos Quânticos
Espécies Reativas de Oxigênio/química
Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
Espectroscopia de Luz Próxima ao Infravermelho
Eletricidade Estática
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Acetates); 0 (Anti-Bacterial Agents); 0 (Ions); 0 (Reactive Oxygen Species); 5GD84Y125G (chloroacetic acid); 7440-57-5 (Gold); F1BC02I72W (Cephradine); FXS1BY2PGL (Mercury)
[Em] Mês de entrada:1610
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151114
[St] Status:MEDLINE
[do] DOI:10.1039/c5nr05619e


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[PMID]:26177093
[Au] Autor:Chen J; Zheng F; Guo R
[Ad] Endereço:Department of Environmental Science, China Pharmaceutical University, 210009, Nanjing, China.
[Ti] Título:Algal Feedback and Removal Efficiency in a Sequencing Batch Reactor Algae Process (SBAR) to Treat the Antibiotic Cefradine.
[So] Source:PLoS One;10(7):e0133273, 2015.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Many previous studies focused on the removal capability for contaminants when the algae grown in an unexposed, unpolluted environment and ignored whether the feedback of algae to the toxic stress influenced the removal capability in a subsequent treatment batch. The present research investigated and compared algal feedback and removal efficiency in a sequencing batch reactor algae process (SBAR) to remove cefradine. Three varied pollution load conditions (10, 30 and 60 mg/L) were considered. Compared with the algal characteristics in the first treatment batch at 10 and 30 mg/L, higher algal growth inhibition rates were observed in the second treatment batch (11.23% to 20.81%). In contrast, algae produced more photosynthetic pigments in response to cefradine in the second treatment batch. A better removal efficiency (76.02%) was obtained during 96 h when the alga treated the antibiotic at 60 mg/L in the first treatment batch and at 30 mg/L in the second treatment batch. Additionally, the removal rate per unit algal density was also improved when the alga treated the antibiotic at 30 or 60 mg/L in the first treatment batch, respectively and at 30 mg/L in the second treatment batch. Our result indicated that the green algae were also able to adapt to varied pollution loads in different treatment batches.
[Mh] Termos MeSH primário: Antibacterianos/isolamento & purificação
Técnicas de Cultura Celular por Lotes/instrumentação
Técnicas de Cultura Celular por Lotes/métodos
Reatores Biológicos
Cefradina/isolamento & purificação
[Mh] Termos MeSH secundário: Biodegradação Ambiental
Chlorella/crescimento & desenvolvimento
Clorofila/análise
Retroalimentação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 1406-65-1 (Chlorophyll); F1BC02I72W (Cephradine)
[Em] Mês de entrada:1605
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150716
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0133273


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[PMID]:26141733
[Au] Autor:Xu YB; Xu JX; Chen JL; Huang L; Zhou SQ; Zhou Y; Wen LH
[Ad] Endereço:School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, People's Republic of China. hopeybxu@163.com.
[Ti] Título:Antioxidative responses of Pseudomonas fluorescens YZ2 to simultaneous exposure of Zn and Cefradine.
[So] Source:Ecotoxicology;24(7-8):1788-97, 2015 Oct.
[Is] ISSN:1573-3017
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Binary pollution of both heavy metals and antibiotics has received increasing attentions for their joint effects of eco-toxicity and health hazards. To reveal the effects of mixtures of different pollutants on bacterial antioxidant response system, Pseudomonas fluorescens ZY2, a new strain isolated from swine wastewater, was chosen to determinate growth (bacterial density OD600), reactive oxygen species (ROS) concentration, protein concentration and superoxide dismutase (SOD) activity under exposure treatments of Zn, Cefradine or Zn + Cefradine. Bacterial densities of all the treatment groups increased significantly over the incubation time, but those containing pollutant addition were slightly lower than the control at different times of incubation. Both ROS concentration and SOD activity increased first and then decreased (p < 0.01) over time, which was opposite to the protein concentrations (p < 0.01), showing a much significant increase by Cefradine alone. With Zn concentration increasing from 40 to 160 mg/L, the intracellular SOD activity increased as a response to the improvement of ROS (p < 0.05), while the balance between ROS and SOD was broken down due to the disproportionate change of total SOD activity and ROS concentration, the bacterial densities therefore decreased for the weak resistance. With the combined treatment of Zn (200 mg/L) and Cefradine (1 mg/L), though the toxicity of Zn caused a much significant increase of ROS, the bacterial resistance was further improved showing a more significant increase of total SOD activity and the bacterial densities therefore increased bacterial growth. Zn concentration also affected the protein synthesis. Either single or binary stress induced the bacterial resistance by regulating SOD activity to eliminate ROS. All results of the bacterial oxidant stress, SOD response and protein synthesis in the combined treatment groups were more complicated than those in single treatment groups, which depended on the properties of the single treatment as well as the interaction between the two treatments upon bacterial activity. For P. fluorescens ZY2, the mediation of SOD activity to eliminate ROS in response to the combined exposure to Zn and Cefradine was first revealed as one of the co-resistance mechanisms, which is informative to further understanding the risk of antibiotics resistant bacteria to human and environmental health more accurately.
[Mh] Termos MeSH primário: Antioxidantes/metabolismo
Cefradina/farmacologia
Farmacorresistência Bacteriana
Pseudomonas fluorescens/efeitos dos fármacos
Pseudomonas fluorescens/fisiologia
Zinco/farmacologia
[Mh] Termos MeSH secundário: Criação de Animais Domésticos
Animais
Antibacterianos/farmacologia
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Espécies Reativas de Oxigênio/metabolismo
Superóxido Dismutase/metabolismo
Sus scrofa
Águas Residuais
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Antioxidants); 0 (Bacterial Proteins); 0 (Reactive Oxygen Species); 0 (Waste Water); EC 1.15.1.1 (Superoxide Dismutase); F1BC02I72W (Cephradine); J41CSQ7QDS (Zinc)
[Em] Mês de entrada:1608
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150705
[St] Status:MEDLINE
[do] DOI:10.1007/s10646-015-1516-7


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[PMID]:26001938
[Au] Autor:Fabbri D; Minella M; Maurino V; Minero C; Vione D
[Ad] Endereço:Department of Chemistry, University of Torino, via P. Giuria 5, 10125 Torino, Italy.
[Ti] Título:A model assessment of the importance of direct photolysis in the photo-fate of cephalosporins in surface waters: Possible formation of toxic intermediates.
[So] Source:Chemosphere;134:452-8, 2015 Sep.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The direct and indirect photodegradation of six cephalosporins was predicted using a photochemical model, on the basis of literature values of photochemical reactivity. Environmental photodegradation would be important in surface water bodies with depth ⩽ 2-3m, and/or in deeper waters with low values of the dissolved organic carbon (DOC ⩽ 1 mg C L(-1)). The half-life times would range from a few days to a couple of weeks in summertime. In deeper and higher-DOC waters and/or in different seasons, hydrolysis could prevail over photodegradation. The direct photolysis of cephalosporins is environmentally concerning because it is known to produce toxic intermediates. It would be a major pathway for cefazolin, an important one for amoxicillin and cefotaxime and, at pH<6.5, for cefapirin as well. In contrast, direct photolysis would be negligible for cefradine and cefalexin. The DOC values would influence the fraction of photodegradation accounted for by direct photolysis in shallow water, to a different extent depending on the role of sensitisation by the triplet states of chromophoric dissolved organic matter.
[Mh] Termos MeSH primário: Cefalosporinas/química
Fotólise
Poluentes Químicos da Água/análise
[Mh] Termos MeSH secundário: Amoxicilina/química
Carbono/química
Cefazolina/química
Cefalexina/química
Cefradina/química
Água Doce/química
Meia-Vida
Concentração de Íons de Hidrogênio
Hidrólise
Modelos Químicos
Modelos Teóricos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Cephalosporins); 0 (Water Pollutants, Chemical); 7440-44-0 (Carbon); 804826J2HU (Amoxicillin); F1BC02I72W (Cephradine); IHS69L0Y4T (Cefazolin); OBN7UDS42Y (Cephalexin)
[Em] Mês de entrada:1602
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150524
[St] Status:MEDLINE


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[PMID]:25684417
[Au] Autor:Guo R; Xie W; Chen J
[Ad] Endereço:Department of Environmental Science, China Pharmaceutical University, 210009 Nanjing, China.
[Ti] Título:Assessing the combined effects from two kinds of cephalosporins on green alga (Chlorella pyrenoidosa) based on response surface methodology.
[So] Source:Food Chem Toxicol;78:116-21, 2015 Apr.
[Is] ISSN:1873-6351
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The present work evaluated the combined effects of cefradine and ceftazidime on the green alga Chlorella pyrenoidosa using response surface methodologies (RSM). After a 48 h-exposure, the population growth rate (PGR), the chlorophyll-a content and the SOD content of the alga increased with increased concentrations of two antibiotics. However, the three responses did not continue to demonstrate significant increases once antibiotic concentrations exceed a moderate level. Three two order polynomial regression equations were obtained to describe well the relationship between the responses of the alga and the two antibiotics' concentration (R(2) = 0.9997, 0.9292 and 0.9039, respectively). Three 3 D-surface graphs and their contour plots showed directly the changing trends of the alga under the combined effects of two antibiotics. This study for the first time employed the RSM in ecotoxicology, which indicated that the RSM should be placed under a feasible and a potential application prospect in toxicity assessment.
[Mh] Termos MeSH primário: Ceftazidima/farmacologia
Cefradina/farmacologia
Chlorella/efeitos dos fármacos
[Mh] Termos MeSH secundário: Antibacterianos/farmacologia
Chlorella/metabolismo
Clorofila/metabolismo
Superóxido Dismutase/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 1406-65-1 (Chlorophyll); 9M416Z9QNR (Ceftazidime); EC 1.15.1.1 (Superoxide Dismutase); F1BC02I72W (Cephradine); YF5Q9EJC8Y (chlorophyll a)
[Em] Mês de entrada:1512
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150217
[St] Status:MEDLINE


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[PMID]:25678231
[Au] Autor:Xu YB; Zhou Y; Ruan JJ; Xu SH; Gu JD; Huang SS; Zheng L; Yuan BH; Wen LH
[Ad] Endereço:School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, People's Republic of China, hopeybxu@163.com.
[Ti] Título:Endogenous nitric oxide in Pseudomonas fluorescens ZY2 as mediator against the combined exposure to zinc and cefradine.
[So] Source:Ecotoxicology;24(4):835-43, 2015 May.
[Is] ISSN:1573-3017
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A better understanding on the mechanism involved in bacterial resistance to combined exposure to antibiotics and heavy metals is helpful in implementing practices to mitigate their ecological risk and spread of resistance genes in microbial population. Pseudomonas fluorescens ZY2, a strain isolated from swine wastewater, was chosen to study its growth (bacterial density OD600), the formation of reactive oxygen species (ROS), nitric oxide (NO) and NO synthases (NOS) under Zn, cefradine or Zn + cefradine treatments. Using Zn and cefradine as representative heavy metal and antibiotic in this investigation, respectively, the resistance of P. fluorescens ZY2 to toxic chemical exposure was investigated. Bacterial densities of treatment groups significantly increased over the time of incubation, but less than the control. ROS, NO and NOS initially increased, but then decreased after the initial 8 h of culturing, and were positively related to Zn concentrations. Moreover, the formation of ROS, NOS, and NO was activated by cefradine at Zn of up to 160 mg/L, but inhibited at Zn of 200 mg/L whether cefradine was added or not. Zn concentration affected ROS and NO concentrations between treatments and also was closely related to the variation of the relative bacterial density. For P. fluorescens ZY2, the mediation of endogenous NO to overcome ROS in response to the combined exposure of Zn and cefradine was suggested as a co-resistance mechanism, which would be beneficial to evaluate the ecological risk of heavy metals and antibiotics.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Cefradina/farmacologia
Pseudomonas fluorescens/efeitos dos fármacos
Poluentes Químicos da Água/farmacologia
Zinco/farmacologia
[Mh] Termos MeSH secundário: Animais
Óxido Nítrico/metabolismo
Óxido Nítrico Sintase/metabolismo
Pseudomonas fluorescens/enzimologia
Pseudomonas fluorescens/metabolismo
Espécies Reativas de Oxigênio/metabolismo
Sus scrofa
Águas Residuais/análise
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Reactive Oxygen Species); 0 (Waste Water); 0 (Water Pollutants, Chemical); 31C4KY9ESH (Nitric Oxide); EC 1.14.13.39 (Nitric Oxide Synthase); F1BC02I72W (Cephradine); J41CSQ7QDS (Zinc)
[Em] Mês de entrada:1512
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150214
[St] Status:MEDLINE
[do] DOI:10.1007/s10646-015-1428-6


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[PMID]:25633105
[Au] Autor:Zhou Y; Xu YB; Xu JX; Zhang XH; Xu SH; Du QP
[Ad] Endereço:School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China. hjzhouyan@163.com.
[Ti] Título:Combined toxic effects of heavy metals and antibiotics on a Pseudomonas fluorescens strain ZY2 isolated from swine wastewater.
[So] Source:Int J Mol Sci;16(2):2839-50, 2015 Jan 27.
[Is] ISSN:1422-0067
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:A Pseudomonas fluorescens strain ZY2, isolated from swine wastewater, was used to investigate the synergistic effects of five heavy metals (Pb, Cu, Zn, Cr(VI) and Hg) on bacterial resistance to antibiotics. Results indicate that the combined effects of antibiotic type, heavy metal type and concentration were significant (p < 0.01). Cross-resistance to Hg and antibiotics was the most noticeable. Moreover, the resistance to Hg and cefradine or amoxicillin, and Cr and amoxicillin were synergistic for low heavy metal concentrations, and turned antagonistic with increasing concentrations, while the resistances to Cr or Cu and cefradine, Pb or Cu and amoxicillin, Cu and norfloxacin showed reverse effects. In addition, resistance to Zn and amoxicillin were always synergetic, while resistance to Pb and cefradine or norfloxacin, Cr or Hg and norfloxacin as well as all the heavy metals and tetracycline were antagonistic. These results indicate that bacterial resistance to antibiotics can be affected by the type and concentration of co-exposed heavy metals and may further threaten people's health and ecological security severely via horizontal gene transfer.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Metais Pesados/toxicidade
Pseudomonas fluorescens/efeitos dos fármacos
Águas Residuais/microbiologia
[Mh] Termos MeSH secundário: Amoxicilina/farmacologia
Animais
Cefradina/farmacologia
Farmacorresistência Bacteriana
Testes de Sensibilidade Microbiana
Norfloxacino/farmacologia
Pseudomonas fluorescens/isolamento & purificação
Suínos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Metals, Heavy); 0 (Waste Water); 804826J2HU (Amoxicillin); F1BC02I72W (Cephradine); N0F8P22L1P (Norfloxacin)
[Em] Mês de entrada:1509
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150131
[St] Status:MEDLINE
[do] DOI:10.3390/ijms16022839


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[PMID]:25590945
[Au] Autor:Zhang H; Xie H; Chen J; Zhang S
[Ad] Endereço:Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology , Dalian 116024, China.
[Ti] Título:Prediction of hydrolysis pathways and kinetics for antibiotics under environmental pH conditions: a quantum chemical study on cephradine.
[So] Source:Environ Sci Technol;49(3):1552-8, 2015 Feb 03.
[Is] ISSN:1520-5851
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Understanding hydrolysis pathways and kinetics of many antibiotics that have multiple hydrolyzable functional groups is important for their fate assessment. However, experimental determination of hydrolysis encounters difficulties due to time and cost restraint. We employed the density functional theory and transition state theory to predict the hydrolysis pathways and kinetics of cephradine, a model of cephalosporin with two hydrolyzable groups, two ionization states, two isomers and two nucleophilic attack directions. Results showed that the hydrolysis of cephradine at pH = 8.0 proceeds via opening of the ß-lactam ring followed by intramolecular amidation. The predicted rate constants at different pH conditions are of the same order of magnitude as the experimental values, and the predicted products are confirmed by experiment. This study identified a catalytic role of the carboxyl group in the hydrolysis, and implies that the carboxyl group also plays a catalytic role in the hydrolysis of other cephalosporin and penicillin antibiotics. This is a first attempt to quantum chemically predict hydrolysis of an antibiotic with complex pathways, and indicates that to predict hydrolysis products under the environmental pH conditions, the variation of the rate constants for different pathways with pH should be evaluated.
[Mh] Termos MeSH primário: Antibacterianos/química
Cefradina/química
Poluentes Químicos da Água/química
[Mh] Termos MeSH secundário: Concentração de Íons de Hidrogênio
Hidrólise
Cinética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Water Pollutants, Chemical); F1BC02I72W (Cephradine)
[Em] Mês de entrada:1512
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150116
[St] Status:MEDLINE
[do] DOI:10.1021/es505383b


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[PMID]:24955615
[Au] Autor:Kang S; Park E; Kim Y; Lee S; Kwon J; Cho H; Lee Y
[Ad] Endereço:Department of Chemistry and.
[Ti] Título:A medusa-like ß-cyclodextrin with 1-methyl-2-(2'-carboxyethyl) maleic anhydrides, a potential carrier for pH-sensitive drug delivery.
[So] Source:J Drug Target;22(7):658-68, 2014 Aug.
[Is] ISSN:1029-2330
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:We developed a new pH-sensitive drug delivery carrier based on ß-cyclodextrin (ß-CD) and 1-methyl-2-(2'-carboxyethyl) maleic anhydrides (MCM). The primary hydroxyl groups of ß-CD were successfully attached to MCM residues to produce a medusa-like ß-CD-MCM. The MCM residue was conjugated with cephradine (CP) with high efficiency ( > 90%). More importantly, ß-CD-MCM-CP responded to the small pH drop from 7.4 to 5.5 and released greater than 80% of the drugs within 0.5 h at pH 5.5. In addition, the inclusion complex between ß-CD-MCM-CP and the adamantane derivative was formed by simple mixing to show the possibility of introducing multi-functionality. Based on these results, ß-CD-MCM can target weakly acidic tissues or organelles, such as tumours, inflammatory tissues, abscesses or endosomes, and be easily modified with various functional moieties, such as ligands for cell binding or penetration, enabling more efficient and specific drug delivery.
[Mh] Termos MeSH primário: Antibacterianos/administração & dosagem
Cefradina/administração & dosagem
Portadores de Fármacos/síntese química
Anidridos Maleicos/química
beta-Ciclodextrinas/química
[Mh] Termos MeSH secundário: Adamantano/química
Animais
Antibacterianos/toxicidade
Sobrevivência Celular/efeitos dos fármacos
Cefradina/toxicidade
Portadores de Fármacos/química
Portadores de Fármacos/toxicidade
Liberação Controlada de Fármacos
Concentração de Íons de Hidrogênio
Camundongos
Estrutura Molecular
Células NIH 3T3
beta-Ciclodextrinas/toxicidade
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Drug Carriers); 0 (Maleic Anhydrides); 0 (beta-Cyclodextrins); F1BC02I72W (Cephradine); JV039JZZ3A (betadex); PJY633525U (Adamantane)
[Em] Mês de entrada:1503
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140624
[St] Status:MEDLINE
[do] DOI:10.3109/1061186X.2014.928718



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