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1.
Chemosphere ; 238: 124680, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31545213

RESUMO

The antibiotic resistance induced by the release of antibiotics to the environment has urged research towards developing effective technologies for antibiotic removal from wastewater. Traditional technologies such as activated sludge processes are not effective for antibiotic removal. Recently, microalgae-based technology has been explored as a potential alternative for the treatment of wastewater containing antibiotics by adsorption, accumulation, biodegradation, photodegradation, and hydrolysis. In this review, the toxicities of antibiotics on microalgae, the mechanisms of antibiotic removal by microalgae, and the integration of microalgae with other technologies such as ultraviolet irradiation (photocatalysis), advanced oxidation, and complementary microorganism degradation for antibiotic removal were discussed. The limitations of current microalgae-based technology and future research needs were also discussed.


Assuntos
Antibacterianos/análise , Antibacterianos/toxicidade , Microalgas/efeitos dos fármacos , Microalgas/metabolismo , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Adsorção , Biodegradação Ambiental , Resistência Microbiana a Medicamentos/fisiologia , Hidrólise , Fotólise , Esgotos/química , Raios Ultravioleta
2.
Mymensingh Med J ; 28(4): 767-772, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31599239

RESUMO

Evaluation of the in vitro antibacterial activity of the ethanolic extract isolated from Cinnamomum zeylanicum bark against two food borne pathogens, Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. This experimental study was carried out in the department of Pharmacology & Therapeutics in collaboration with the department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh from July 2017 to July 2018. The antibacterial activity was tested at different concentrations of extracts of spice by using disc diffusion method. The extracts were prepared by using a solvent ethanol. The test microorganisms were also tested for their activity against a standard antibiotic Amikacin (500mg) by disc diffusion method and the result was compared with that of ethanolic extracts. Cinnamon had inhibitory activity against both Staphylococcus aureus and Escherichia coli. The ethanolic extracts were more effective against Staphylococcus aureus than E. coli. Staphylococcus aureus showed activity from 60% conc. (zone of inhibition 17mm) where E. coli from 80% conc. (ZOI 18mm). Maximum zone of inhibition was 26mm for both the test organisms. This result was also compared to those obtained against a standard antibiotic Amikacin where extract produced wider zone of inhibition of 26mm as compared to Amikacin for both test organisms. The present study showed that ethanolic extract of cinnamon demonstrated stronger antimicrobial effect against food borne pathogens.


Assuntos
Antibacterianos/toxicidade , Cinnamomum zeylanicum , Escherichia coli/efeitos dos fármacos , Extratos Vegetais/toxicidade , Staphylococcus aureus/efeitos dos fármacos , Bangladesh , Etanol , Microbiologia de Alimentos , Humanos
3.
Mymensingh Med J ; 28(4): 779-791, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31599241

RESUMO

Evaluation of the in vitro antibacterial activity of aqueous and ethanolic extracts isolated from Clove (Syzygium aromaticum) buds against three food borne pathogens, gram-positive Staphylococcus aureus and gram-negative Escherichia coli & Pseudomonas aeruginosa. This interventional study was carried out during the period of July 2018 to June 2019 in the Department of Pharmacology and Therapeutics with the collaboration of Department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh. The antibacterial activity was tested at different concentrations of both extracts of spice by using disc diffusion & broth dilution method. The extracts were prepared by using solvents aqueous & ethanol. The test microorganisms were also tested for their activity against a standard antibiotic Gentamicin (80mg) by broth dilution method and the result was compared with that of Aqueous and Ethanolic extracts. Aqueous and ethanolic extracts of clove had inhibitory activity against the test bacteria. Among different concentrations of the ACE, 500µg/ml & above concentration showed inhibitory effect against Staphylococcus aureus & Escherichia coli and 700µg/ml & above concentration showed inhibitory effect against Pseudomonas aeruginosa. In case of ECE, 500µg/ml & above concentration showed inhibitory effect against aforesaid bacteria. In disc diffusion method, S. aureus was found to be most susceptible to ACE (30.5mm) & Pseudomonas aeruginosa was found to be most susceptible to ECE (38mm). Minimum inhibitory concentrations (MIC) of ECE were lower than ACE for the test bacteria except Staphylococcus aureus where MICs of ACE & ECE were the same. This result was also compared against a standard antibiotic Gentamicin where the MICs of Gentamicin were lower in comparison to MICs of ACE & ECE. The present study showed that aqueous and ethanolic extracts of Clove demonstrated antibacterial effects against food borne pathogens.


Assuntos
Antibacterianos/toxicidade , Extratos Vegetais/toxicidade , Syzygium , Bangladesh , Escherichia coli/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
4.
J Microbiol ; 57(9): 781-794, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31452043

RESUMO

The phytopathogenic Burkholderia species B. glumae and B. plantarii are the causal agents of bacterial wilt, grain rot, and seedling blight, which threaten the rice industry globally. Toxoflavin and tropolone are produced by these phytopathogens and are considered the most hostile biohazards with a broad spectrum of target organisms. However, despite their nonspecific toxicity, the effects of toxoflavin and tropolone on bacteria remain unknown. RNA-seq based transcriptome analysis was employed to determine the genome-wide expression patterns under phytotoxin treatment. Expression of 2327 and 830 genes was differentially changed by toxoflavin and tropolone, respectively. Enriched biological pathways reflected the down-regulation of oxidative phosphorylation and ribosome function, beginning with the inhibition of membrane biosynthesis and nitrogen metabolism under oxidative stress or iron starvation. Conversely, several systems such as bacterial chemotaxis, flagellar assembly, biofilm formation, and sulfur/taurine transporters were highly expressed as countermeasures against the phytotoxins. In addition, our findings revealed that three hub genes commonly induced by both phytotoxins function as the siderophore enterobactin, an iron-chelator. Our study provides new insights into the effects of phytotoxins on bacteria for better understanding of the interactions between phytopathogens and other microorganisms. These data will also be applied as a valuable source in subsequent applications against phytotoxins, the major virulence factor.


Assuntos
Antibacterianos/toxicidade , Burkholderia/química , Proteínas de Escherichia coli/genética , Escherichia coli/efeitos dos fármacos , Doenças das Plantas/microbiologia , Pirimidinonas/toxicidade , Triazinas/toxicidade , Tropolona/toxicidade , Antibacterianos/metabolismo , Burkholderia/metabolismo , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Oryza/microbiologia , Pirimidinonas/metabolismo , Transcriptoma/efeitos dos fármacos , Triazinas/metabolismo , Tropolona/metabolismo
5.
Environ Pollut ; 254(Pt B): 112861, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31454568

RESUMO

As a new type of pollutant, fluoroquinolones (FQs) antibiotics are ubiquitous in environment and have some threat to human health and ecological environment. Their ecological toxicity to the environment urgently need to be assessed. Therefore, we firstly explored the toxic effects and possible mechanism of cardiovascular toxicity induced by gatifloxacin (GTFX) and ciprofloxacin (CPFX) using zebrafish model. After 24 h exposure, the zebrafish treated with GTFX showed pericardial edema which was further investigated by histopathological examination, while CPFX exposure did not induce morphological abnormalities. However, both of them induced cardiac dysfunction, such as decreased heart rate and cardiac output which was showed a positive correlation with the concentration. To better understand the possible molecular mechanisms underlying cardiovascular toxicity in zebrafish, we investigated the transcriptional level of genes related to calcium signaling pathway and cardiac muscle contraction. The results indicated that the expression of ATPase (atp2a1l) and cardiac troponin C (tnnc1a) genes were significantly inhibited, the expression of calcium channel (cacna1ab) gene showed slight promoted trend after CPFX exposure. For zebrafish treated with GTFX, the expression of atp2a1l genes was also significantly inhibited, while the expression of tnnc1a genes was slightly inhibited and cacna1ab genes expression had no obvious effect. The present study firstly revealed that GTFX exposure can induce morphological and functional abnormalities on the cardiovascular system of zebrafish. Though CPFX exposure did not induce morphological abnormalities, the function of cardiovascular system was still damaged. Mechanistically, this toxicity might result from the pressure of down-regulation of genes associated with calcium signaling pathway and cardiac muscle contraction. The results of this study can provide a valuable theoretical basis for the establishment of FQs environmental quality standards in water environment, environmental drug regulation and risk management.


Assuntos
Antibacterianos/toxicidade , Sistema Cardiovascular/efeitos dos fármacos , Ciprofloxacino/toxicidade , Gatifloxacina/toxicidade , Animais , Fenômenos Fisiológicos Cardiovasculares/efeitos dos fármacos , Sistema Cardiovascular/crescimento & desenvolvimento , Regulação para Baixo , Frequência Cardíaca/efeitos dos fármacos , Humanos , Modelos Animais , Contração Miocárdica/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/crescimento & desenvolvimento
6.
Environ Pollut ; 254(Pt B): 113063, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31454585

RESUMO

Propylea japonica is a very important predator in agricultural ecosystems, which could be exposed to Bt protein. In this study, the bacterial community of P. japonica fed with normal food and food containing Cry2Ab protein was characterized for the first time using qPCR and high-throughput sequencing approaches. Results showed no effect of Cry2Ab on P. japonica development and reproduction. The most abundant bacterial phylum was Firmicutes, and the most abundant genus was Staphylococcus. The total bacteria copy number was not significantly different across four larval stages. Bacteria species composition was gathered more closely in feed on sucrose solution (sucrose-fed) than in larvae only fed on pea aphid (aphid-fed), the diversity indices of some operational taxonomic unit (OTU) were significantly different between sucrose-fed and aphid-fed samples. Different instar larval stages of P. japonica fed with sucrose solution containing Cry2Ab Bt protein and found no effect on microbial community composition and total bacteria copy numbers. However, effects on relative abundance of microbes, copy numbers of Corynebacterium 1 and Glutamicibacter arilaitensis were observed significantly lower in Bt-fed first and fourth larval stages. Low and high concentrations of Cry2Ab protein altered the microbial abundance relative to sucrose-fed P. japonica and copy numbers of G. arilaitensis and Staphylococcus xylosus were significantly lower in Bt-fed samples than control sucrose-fed. Our results are the first report showing that feeding on Cry2Ab protein does not alter microbial species composition in P. japonica, but effects gene copy number of some dominant bacteria. Further investigations are needed to assess the effect of copy number change on P. japonica.


Assuntos
Antibacterianos/toxicidade , Proteínas de Bactérias/toxicidade , Besouros/microbiologia , Endotoxinas/toxicidade , Proteínas Hemolisinas/toxicidade , Animais , Afídeos/metabolismo , Bactérias/metabolismo , Proteínas de Bactérias/genética , Besouros/efeitos dos fármacos , Ecossistema , Proteínas Hemolisinas/metabolismo , Larva/efeitos dos fármacos
7.
Ecotoxicol Environ Saf ; 183: 109508, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31408819

RESUMO

As a new type of antibacterial agent, nanosilver has attracted great attention in biomedical applications. However, the safety of nanosilver to humans and the environment has not been well elucidated. The objective of this study was to investigate the influence of nanosilver on novel effector mechanism of neutrophil extracellular traps (NETs), and its possible molecular mechanisms. In this study, nanosilver (10, 20 and 40 µg/mL) was incubated with neutrophils for 90 min. Then, nanosilver-induced the release of NETs was observed by laser confocal microscopy. Nanosilver-induced NETs release was also quantitatively detected by pico Green®. In addition, the role of NADPH oxidase, extracellular signal-regulated kinase (ERK) and p38 signaling pathways in nanosilver-induced NETs release were detected by the inhibitors and pico Green®. The results indicated that nanosilver significantly activated polymorphonuclear neutrophils (PMN) to release NETs, which was a DNA-based network structure modified with histones (H3) and neutrophil elastase (NE). The inhibitors of NADPH oxidase, ERK and p38 signaling pathways significantly inhibited the formation of nanosilver-induced NETs. Furthermore, nanosilver did not alter the extracellular lactate dehydrogenase (LDH) level of PMN cells. All these results showed that nanosilver significantly induced NETs release, and the potential molecular mechanisms were correlated with reactive oxygen species (ROS) production-dependent on NADPH oxidase, ERK and p38 signaling pathways, which might provide a new perspective on nanosilver-induced excess NETs release related to the host immune damage.


Assuntos
Antibacterianos/toxicidade , Armadilhas Extracelulares/metabolismo , Nanopartículas Metálicas/toxicidade , Neutrófilos/efeitos dos fármacos , Prata/toxicidade , Animais , Antibacterianos/química , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Nanopartículas Metálicas/química , Camundongos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NADPH Oxidases/antagonistas & inibidores , NADPH Oxidases/metabolismo , Neutrófilos/enzimologia , Neutrófilos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Prata/química
8.
Food Chem ; 301: 125247, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31377626

RESUMO

In this work, we developed a simple method for the preparation of N-(3-azido-2-hydroxypropyl)chitosan. We compared the antibacterial activity of N-(3-azido-2-hydroxypropyl)chitosans and previously synthesized N-(2-azidoethyl)chitosans. N-(3-azido-2-hydroxypropyl)chitosans possess higher antibacterial effect which is comparable with that of ampicillin and gentamicin. The effect is due to azido pharmacophore -CH2-CH(OH)-CH2-N3 (for N-(3-azido-2-hydroxypropyl)chitosan) or -CH2-CH2-N3 (for N-(2-azidoethyl)chitosan) introduced in chitosan chain, since the corresponding organic azides NH2-CH2-CH2-N3 and NH2-CH2-CH2-N3 are characterized by high antibacterial activity. However, high antibacterial organic azides NH2-CH2-CH2-N3 and NH2-CH2-CH2-N3 are characterized by high toxicity. Their conjugation to the chitosan chain saves their antibacterial effect, but strongly diminishes their toxicity, and the toxicity of the resulting derivatives is comparable with that of the starting chitosan. These findings are of interest to food science, since novel effective food coatings can be developed on basis of prepared derivatives.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Azidas/química , Quitosana/química , Quitosana/farmacologia , Embalagem de Alimentos , Antibacterianos/toxicidade , Quitosana/toxicidade
9.
Adv Exp Med Biol ; 1145: 289-304, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31364083

RESUMO

Polymyxin toxicity remains a significant concern that limits the clinical utility of this class of antibacterials for patient care. The most notable adverse event is the dose- and treatment-limiting nephrotoxicity that occurs in roughly 30-60% of patients receiving a systemic polymyxin. This chapter focuses on this adverse event with a detailed assessment of the incidence of, and risk factors for, polymyxin-associated nephrotoxicity. In particular, the text focuses on the impact of dose, serum concentrations, and polymyxin selection on nephrotoxicity. Additionally, less common, but clinically important adverse events are discussed.


Assuntos
Antibacterianos/toxicidade , Polimixinas/toxicidade , Humanos , Incidência , Fatores de Risco
10.
Adv Exp Med Biol ; 1145: 305-319, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31364084

RESUMO

Polymyxin-induced nephrotoxicity is the major dose-limiting factor and can occur in up to 60% of patients after intravenous administration. This chapter reviews the latest literature on the mechanisms of polymyxin-induced nephrotoxicity and its amelioration. After filtration by glomeruli, polymyxins substantially accumulate in renal proximal tubules via receptor-mediated endocytosis mainly by megalin and PEPT2. It is believed that subsequently, a cascade of interconnected events occur, including the activation of death receptor and mitochondrial apoptotic pathways, mitochondrial damage, endoplasmic reticulum stress, oxidative stress and cell cycle arrest. The current literature shows that oxidative stress plays a key role in polymyxin-induced kidney damage. Use of antioxidants have a potential in the attenuation of polymyxin-induced nephrotoxicity, thereby widening the therapeutic window. Mechanistic findings on polymyxin-induced nephrotoxicity are critical for the optimization of their use in the clinic and the discovery of safer polymyxin-like antibiotics.


Assuntos
Antibacterianos/toxicidade , Nefropatias/induzido quimicamente , Rim/efeitos dos fármacos , Polimixinas/toxicidade , Apoptose , Estresse do Retículo Endoplasmático , Humanos , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo
11.
Sci Total Environ ; 695: 133811, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31419687

RESUMO

Nitrification and denitrification are the most important nitrogen transformation processes in the environment. Recently, due to widespread use, antibiotics have been reported to lead to environmental risks. Tetracycline (TC) is one of the most extensively used antibiotics in many areas. However, its reported effects on nitrogen transformations were conflicting in previous studies. In this study, the effects of TC on nitrogen transformations in sediment were investigated by analyzing TC transport and bacterial activity. It was found that the adsorption of TC onto the sediment was favorable and spontaneous, with adsorption capacity 54.3 mg/kg. The adsorption kinetics of TC onto the sediment and the isotherm fitted the Elvoich and Freundlich models, respectively, indicating that the adsorption was a chemisorption process, including electrostatic interactions and chemical bonding between TC and the sediment. TC showed no effect on nitrification in the sediment, but significantly inhibited the reduction of nitrate and nitrite during denitrification, consistent with observations made for the model denitrifier Paracoccus denitrificans under TC stress. Mechanistic study indicated that TC at 130 µg/g-cell inhibited 50.7% of P. denitrificans growth and 61.6% of cell viability. Meanwhile, the catalytic activities of the key denitrifying enzymes, nitrate reductase (NAR) and nitrite reductase (NIR), decreased to 29.1% and 68.0% of the control levels when the TC concentration was 130 µg/g-cell, suggesting that NAR was more sensitive to the TC than NIR, which contributed to a delay in nitrite accumulation.


Assuntos
Antibacterianos/toxicidade , Bactérias/efeitos dos fármacos , Sedimentos Geológicos/microbiologia , Nitrogênio/metabolismo , Tetraciclina/toxicidade , Adsorção , Desnitrificação/efeitos dos fármacos , Sedimentos Geológicos/química , Nitrificação/efeitos dos fármacos , Paracoccus denitrificans/efeitos dos fármacos , Paracoccus denitrificans/fisiologia
12.
Sci Total Environ ; 695: 133804, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31419690

RESUMO

Once released into the environment antibiotics can kill or inhibit the growth of bacteria, and in turn potentially have effects on bacterial community structure and ecosystem function. Environmental risk assessment (ERA) seeks to establish protection limits to minimise chemical impacts on the environment, but recent evidence suggests that the current regulatory approaches for ERA for antibiotics may not be adequate for protecting bacteria that have fundamental roles in ecosystem function. In this study we assess the differences in interspecies sensitivity of eight species of cyanobacteria to seven antibiotics (cefazolin, cefotaxime, ampicillin, sufamethazine, sulfadiazine, azithromycin and erythromycin) with three different modes of action. We found that variability in the sensitivity to these antibiotics between species was dependent on the mode of action and varied by up to 70 times for ß-lactams. Probabilistic analysis using species sensitivity distributions suggest that the current predicted no effect concentration PNEC for the antibiotics may be either over or under protective of cyanobacteria dependent on the species on which it is based and the mode of action of the antibiotic; the PNECs derived for the macrolide antibiotics were over protective but PNECs for ß-lactams were generally under protective. For some geographical locations we identify a significant risk to cyanobacteria populations based upon measured environmental concentrations of selected antibiotics. We conclude that protection limits, as determined according to current regulatory guidance, may not always be protective and might be better derived using SSDs and that including toxicity data for a wider range of (cyano-) bacteria would improve confidence for the ERA of antibiotics.


Assuntos
Antibacterianos/toxicidade , Cianobactérias/fisiologia , Poluentes Químicos da Água/toxicidade , Antibacterianos/análise , Cianobactérias/efeitos dos fármacos , Monitoramento Ambiental , Medição de Risco , Poluentes Químicos da Água/análise
13.
Environ Sci Pollut Res Int ; 26(26): 27112-27127, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31317435

RESUMO

In this study, we screened for the antifouling activity of 15 species plant extracts from Brazilian the Brazilian Caatinga Fabaceae against the initial colonization of natural marine bacterial biofilm. We also investigated the potential toxicity of extracts against planktonic and benthic non-target organisms. Aqueous extracts of plants collected in the Caatinga biome (PE, Brazil) were prepared and tested at different concentration levels (0, 0.5, 1, 2, 4, and 8 mg mL-1). Natural marine bacterial consortium was inoculated in multi-well plates and incubated with the different treatments for 48 h. The biofilm and planktonic bacterial density and biomass inhibition were evaluated along with biofilm biomass eradication. The extracts that showed the highest bacterial biofilm inhibition were evaluated for toxicity against microalgae and crustaceans. The biofilm and planktonic bacterial inhibition potential were evaluated through flow cytometry and spectrophotometry. The selected treatments were evaluated for their toxicity using the microalgae Chaetoceros calcitrans, the copepod Nitokra sp., and the brine shrimp Artemia salina as bioindicators. Our work demonstrates the biotechnological potential of Fabaceae plant compounds as a safe antifouling alternative. Anadenanthera colubrina var. cebil fruits and Apuleia leiocarpa leaf extracts showed antibiofilm activity (≥ 80%), while Myroxylon peruiferum and Dioclea grandiflora leaf extracts showed antibiotic activity. These extracts were safe to planktonic and benthic non-target organisms. The results of this study point to potential substitutes to highly toxic antifouling paints and shed light on the prospect of a yet to be explored biome for more sustainable alternatives in biofouling research.


Assuntos
Incrustação Biológica/prevenção & controle , Desinfetantes/farmacologia , Fabaceae/química , Extratos Vegetais/farmacologia , Animais , Antibacterianos/farmacologia , Antibacterianos/toxicidade , Artemia/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Brasil , Copépodes/efeitos dos fármacos , Diatomáceas/efeitos dos fármacos , Desinfetantes/toxicidade , Ecotoxicologia/métodos , Microalgas/efeitos dos fármacos , Pintura , Plâncton/efeitos dos fármacos , Plâncton/microbiologia , Extratos Vegetais/toxicidade
14.
Clin Nephrol ; 92(4): 201-207, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31347498

RESUMO

AIMS: Several studies have reported that critically ill patients who require amikacin for the treatment of severe infection require therapeutic drug monitoring (TDM) to prevent acute kidney injury. Moreover, studies so far have mainly focused on patients with critical illnesses; therefore, the probability of occurrence of nephrotoxicity in noncritically ill patients is less known and tends to be overestimated. Recently, with the emergence of multidrug resistant bacteria, the need for aminoglycosides has resurfaced. Therefore, the aim of this study was to investigate the nephrotoxicity and tolerability of amikacin in noncritically ill patients. MATERIALS AND METHODS: This was a retrospective study that included 224 patients who were administered amikacin. Relevant data on patients' clinical course of disease, comorbidities, and clinical laboratory measurements were statistically analyzed. Nephrotoxicity was defined as a serum creatinine level increase by ≥ 0.3 mg/dL or ≥ 50% after therapy initiation. RESULTS: The mean (SD) daily amikacin dose was 13.04 (4.21) mg/kg. The mean (SD) duration of treatment was 12.09 (12.89) days. The incidence rate (95% CI) of amikacin-induced nephrotoxicity was 1.076/person-year (0.46 - 2.12) for the total person-time (3.44 years). In the risk analysis, no risk factor associated with nephrotoxicity could be found. However, an increasing trend of AKI risk was observed in patients with low baseline estimated glomerular filtration rate. CONCLUSION: In noncritically ill patients, the incidence of amikacin-induced nephrotoxicity was lower than that reported in previous studies. The initial monitoring for kidney function in clinical laboratories may be useful, and therapeutic drug monitoring (TDM) may not be necessary in patients with normal kidney function.


Assuntos
Lesão Renal Aguda/induzido quimicamente , Amicacina/toxicidade , Antibacterianos/toxicidade , Estado Terminal , Adulto , Idoso , Monitoramento de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
15.
Ecotoxicol Environ Saf ; 182: 109415, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31299471

RESUMO

Erythromycin (ERY), azithromycin (AZI) and telithromycin (TEL) are widely-used macrolide antibiotics that are frequently detected in various water environments, including resource water and drinking water. In the performed chlorination disinfection process, at least 10, 20 and 200 new disinfection byproducts of ERY, AZI and TEL, respectively, were observed (the mixtures of the disinfection byproducts of ERY, AZI and TEL were named ERY-M, AZI-M and TEL-M, respectively). There is limited information available regarding their comparative toxicities, and their potential health risks are still unknown. In this study, the Jurkat cell line was used to compare the toxicities of the disinfection byproduct mixtures and their precursor compounds. The cell viability results indicated that the toxicity of ERY-M may not be enhanced after disinfection by chlorination. In contrast, at the same concentrations, AZI-M and TEL-M induced more significant inhibitory effects on cell viability than their parent compounds. Additionally, the total antioxidant capacity (T-AOC) and cell cytokine release (including interleukin-2, interleukin-8 and tumor necrosis factor-α) analyses of AZI-M and TEL-M further verified these results. Our findings demonstrate that the cytotoxicity of AZI and TEL was enhanced during the chlorination disinfection process. This investigation will provide substantial new details related to the toxicity of the mixed disinfection byproducts (DBPs) of ERY, AZI and TEL generated in the chlorination disinfection process.


Assuntos
Antibacterianos/toxicidade , Desinfetantes/toxicidade , Antibacterianos/análise , Desinfetantes/análise , Desinfecção/métodos , Água Potável/análise , Eritromicina/análise , Halogenação , Cetolídeos , Testes de Toxicidade , Poluentes Químicos da Água/análise , Purificação da Água/métodos
16.
Environ Pollut ; 253: 152-160, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31306822

RESUMO

Antibiotic contamination caused by the long-term use of organic manure (OM) in greenhouse agricultural soils poses potential detrimental effects to the soil environment. By applying OM containing chlortetracycline (CTC) and/or ciprofloxacin (CIP) ten times in soil under laboratory conditions, we investigated the dissipation and accumulation characteristics of CTC and CIP in the soil, the changes in the microbial pollution-induced community tolerance (PICT), and the diversity and abundance of antibiotic resistance genes (ARGs) in the soil microbiome. The dissipation of CTC was rapid while CIP was accumulated in repeatedly treated soils; further, CIP could inhibit the dissipation of CTC. Meanwhile, the PICT to CTC and/or CIP significantly increased up to 15.0-fold after ten successive treatments compared to that in the first treatment. As the treatment frequency increased, significant upward trends in the abundances of tetracycline resistance genes tetA(G), tetX2, tetX, tetG, tetA(33), tetA, tetW, and tetA(P), fluoroquinolone resistance gene qnrA6, and multiple resistance gene mexF were revealed by both metagenomic and qPCR analyses. The findings demonstrated that repeated treatments with CTC and/or CIP can alter the dissipation rate, promote an increase in PICT to CTC and/or CIP, and increase the ARGs abundance in steps.


Assuntos
Antibacterianos/toxicidade , Clortetraciclina/toxicidade , Ciprofloxacino/toxicidade , Resistência Microbiana a Medicamentos/genética , Microbiologia do Solo , Agricultura , Clortetraciclina/análise , Esterco/análise , Metagenômica , Microbiota/efeitos dos fármacos , Solo , Tetraciclina/farmacologia , Resistência a Tetraciclina
17.
Chemosphere ; 235: 344-353, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31265980

RESUMO

The ecological risks of antibiotics in aquatic environments have raised great concerns worldwide, but the chronic effect of antibiotic contaminants on cyanotoxin production and release remains unclear. This study investigated the long-term combined effects of spiramycin (SP) and ampicillin (AMP) on microcystin (MC) production and release in both unicellular and colonial Microcystis aeruginosa (MA) through semi-continuous exposure test. At exposure concentration of 300 ng L-1, MA growth rates were stimulated till the end of exponential phase accompanied with the up-regulation of photosynthesis-related gene. The exponential growth phases of unicellular and colonial MA were prolonged for 2 and 4 days, respectively. The stimulation rate of growth rate and MC content in unicellular MA were significantly higher than that in colonial MA. The highest concentrations of intracellular MC (IMC) and extracellular MC (EMC) were observed in the binary mixture at equivalent SP/AMP ratio (1:1). The promotion of IMC concentration was in consistent with the stimulated expression of MC-synthesis-related gene and nitrogen-transport-related gene. The malondialdehyde content and activities of superoxide dismutase and catalase in unicellular MA were significantly higher than those in colonial MA. The EMC concentration and the antioxidant responses of both unicellular and colonial MA significantly increased with exposure time. Long-term exposure to mixture of SA and AMP at environmentally relevant concentrations would aggravate the disturbance to aquatic ecosystem balance through the stimulation of MA proliferation as well as the promotion of MC production and release.


Assuntos
Antibacterianos/toxicidade , Microcistinas/metabolismo , Microcystis/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Ampicilina , Antibacterianos/farmacologia , Ecossistema , Microcistinas/biossíntese , Microcystis/crescimento & desenvolvimento , Microcystis/metabolismo , Nitrogênio/metabolismo , Fotossíntese/efeitos dos fármacos , Espiramicina , Poluentes Químicos da Água/metabolismo
18.
Carbohydr Polym ; 218: 289-298, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31221332

RESUMO

Bacterial infections are a growing global challenge for public health as antibiotic resistance could cause the failure of anti-infective treatment eventually. So, it is urgent to develop new potential antibacterial materials. Herein, a multifunctional chitosan (CS) functionalized magnetic Chlorin e6 (CS-MP-Ce6) was constructed to combat methicillin-resistant Staphylococcus aureus (MRSA) infection by integrating bacterial conjugation and enrichment, and near-infrared (NIR)-triggered photodynamic sterilization. CS-MP-Ce6 could efficiently capture bacteria due to positively charged property of CS, and Ce6 acted as an effective photodynamic killer to convert NIR light into local energy to enhance antibacterial activity. Specifically, after being trapped together with MRSA, CS-MP-Ce6 showed an excellent in vitro photodynamic sterilization ability. In vivo MRSA-induced abscess treatment studies showed faster healing when CS-MP-Ce6 was used as subcutaneous nano-localized energy sources with the assistance of external magnet to concentrate CS-MP-Ce6-bacteria conjugate. This work provides a promising framework for constructing a new system for efficiently combating MRSA.


Assuntos
Antibacterianos/uso terapêutico , Indóis/química , Nanopartículas de Magnetita/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Fármacos Fotossensibilizantes/uso terapêutico , Polímeros/química , Porfirinas/uso terapêutico , Animais , Antibacterianos/efeitos da radiação , Antibacterianos/toxicidade , Quitosana/química , Raios Infravermelhos , Camundongos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/efeitos da radiação , Fármacos Fotossensibilizantes/toxicidade , Porfirinas/efeitos da radiação , Porfirinas/toxicidade , Células RAW 264.7
19.
Environ Pollut ; 252(Pt B): 1097-1105, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31252107

RESUMO

The application of compost in agriculture has led to the accumulation of antibiotic resistance genes (ARGs) and heavy metal resistance genes (MRGs) in the soil environment. In this study, the response of ARGs and MRGs to bamboo charcoal (BC) and bamboo vinegar (BV) during aerobic composting was investigated. Results showed that BC + BV treatment reduced the abundances of ARGs and mobile genetic elements (MGEs) during the thermophilic period, as well as achieved the lowest rebound during the cooling period. BC + BV promoted the growth of Firmicutes, thereby facilitating the thermophilic period of composting. The rebound of ARGs and MGEs can be explained by increasing the abundance of Actinobacteria and Proteobacteria at the end of composting. Composting reduced the abundances of MRGs comprising pcoA, tcrB, and cueO, whereas cusA and copA indicated the selective pressure imposed by heavy metals on bacteria. The fate of ARGs was mainly driven by MGEs, and heavy metals explained most of the variation in MRGs. Interestingly, nitrogen conversion also had an important effect on ARG and MRG profiles. Our current findings suggest that the addition of BC + BV during compost preparation is an effective method in controlling the mobility of ARGs and MRGs, thereby reducing the environmental problems.


Assuntos
Ácido Acético/farmacologia , Carvão Vegetal/química , Compostagem , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos/efeitos dos fármacos , Sasa/química , Aerobiose , Antibacterianos/toxicidade , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Metais Pesados/toxicidade , Nitrogênio/análise , Solo/química
20.
An Acad Bras Cienc ; 91(2): e20180468, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31241699

RESUMO

This study evaluates the antibacterial, cytotoxic activities, and phytochemical composition, of Callistemon citrinus, Hibiscus rosa-sinensis and Plumbago auriculata leaves and flowers, three ornamental plants in Mexico. However, in other countries offers a range of other uses. Ethanol extracts of C. citrinus leaf and flower presented stronger antibacterial activity than the extracts obtained from the other two plants. C. citrinus leaf showed low cytotoxicity (LC50 <600 µg/mL) on the brine shrimp test, whereas the ethanol extracts of H. rosa-sinensis and P. auriculata leaves showed no cytotoxic activity. Flower extracts obtained from the three plants did no exhibit cytotoxicity. GC-MS analysis revealed that the ethanol extract of P. auriculata leaf contained lupeol triterpene and lupeol acetate, neither of them have been previously reported in this genus. Gamma sitosterol was present in the leaf and flower extracts of P. auriculata. Higher contents of linoleic and linolenic acids were found in extracts of H. rosa-sinensis leaves and flowers. The ability of the ethanol extracts of C. citrinus leaves and flowers to inhibit the growth of Gram-positive and Gram-negative bacteria indicates a potentially broad antimicrobial spectrum. Moreover, the absence of cytotoxicity suggests the potential use of this plant to treat microbial infections.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hibiscus/química , Myrtaceae/química , Extratos Vegetais/farmacologia , Plumbaginaceae/química , Animais , Antibacterianos/toxicidade , Artemia/efeitos dos fármacos , México , Testes de Sensibilidade Microbiana , Extratos Vegetais/toxicidade , Testes de Toxicidade
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