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1.
Chemosphere ; 263: 128117, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297110

RESUMO

Untreated pharmaceutical pollution and their possibly toxic metabolites, resulting from overloaded wastewater treatment processes, end up in aquatic environments and are hazardous to the ecosystem homeostasis. Biological wastewater remediation could supplement traditional methods and overcome the release of these biologically active compounds in the environment. Mycoremediation is especially promising due to the unspecific nature of fungi to decompose compounds through exoenzymes and the uptake of compounds as nutrients. In the present study, we improved on the previous advances made using the fungus Mucor hiemalis to remediate one of the most commonly occurring pharmaceuticals, acetaminophen (APAP), at higher concentrations. The limitation of nitrogen, adjustment of pH, and comparison to, as well as co-cultivation with the white-rot fungus Phanerochaete chrysosporium, were tested. Nitrogen limitation did not significantly improve the APAP remediation efficiency of M. hiemalis. Maintaining the pH of the media improved the remediation restraint of 24 h previously observed. The APAP remediation efficiency of P. chrysosporium was far superior to that of M. hiemalis, and co-cultivation of the two resulted in a decreased remediation efficiency compared to P. chrysosporium in single.


Assuntos
Acetaminofen , Phanerochaete , Biodegradação Ambiental , Ecossistema , Mucor
2.
Ecotoxicol Environ Saf ; 74(1): 74-7, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20447690

RESUMO

Free-living freshwater cyanobacteria contain BMAA in both free cellular and protein-associated forms. Free BMAA released on bloom collapse or during cellular turnover creates a potential source of the non-proteinogenic amino acid for bioaccumulation and biomagnification in aquatic ecosystems. Uptake of free amino acids is well documented in macrophytes and the potential for aquatic macrophytes to bioaccumulate BMAA therefore poses a potential threat where such macrophytes constitute a food source in an ecosystem. BMAA uptake and accumulation by the aquatic macrophyte Ceratophyllum demersum was therefore investigated. Rapid uptake of significant amounts of BMAA was observed in C. demersum. Both free and protein-associated BMAA were observed with protein association following accumulation of free BMAA. The protein association suggests potential biomaccumulation by aquatic macrophytes and offers a possibility of phytoremediation for BMAA removal.


Assuntos
Diamino Aminoácidos/toxicidade , Ecossistema , Magnoliopsida/efeitos dos fármacos , Neurotoxinas/toxicidade , Poluentes Químicos da Água/toxicidade , Diamino Aminoácidos/metabolismo , Cianobactérias/química , Cianobactérias/metabolismo , Toxinas de Cianobactérias , Água Doce , Magnoliopsida/crescimento & desenvolvimento , Magnoliopsida/metabolismo , Neurotoxinas/metabolismo , Poluentes Químicos da Água/metabolismo
3.
S Afr Med J ; 100(7): 442-4, 2010 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-20822591

RESUMO

BACKGROUND: During inflammation, the serum concentrations of granulocyte colony stimulating factor (G-CSF), plasma interleukin-6 (IL-6), and C-reactive protein (CRP) increase. A positive correlation between CRP and the percentages of neutrophils exhibiting toxic granulation during inflammation has been demonstrated, and that the fluctuations of CRP and toxic granulation of neutrophils were similar. OBJECTIVES: We studied whether grading of toxic granulated neutrophils can be used as a surrogate marker for infection or inflammation, and also be an easier method than previously described methods. MATERIALS AND METHODS: We graded 357 consecutive peripheral blood slides from patients on whom a full blood count with differential count and CRP level was performed, according to intensity of toxic granulation in the neutrophil population, according to a newly proposed grading system. RESULTS: The CRP range was between 1 and 530.3 mg/l. The results confirm the association between a rise in CRP and progressive intensity of toxic granulation in neutrophils in peripheral blood. Kruskal-Wallis equality of populations rank test showed a statistically significant difference between the graded categories (p=0.0001). The Trend test was also statistically significant (p=0.000). CONCLUSION: The proposed system can be applied to patients with inflammatory or infectious conditions, where grading of toxic granulation of neutrophils can possibly be used as a surrogate marker to assess infection or inflammation and their response to treatment. It may be of particular use in cases where traditional infectious or inflammatory markers cannot be used, owing to inherent problems associated with the respective conditions.


Assuntos
Proteína C-Reativa/análise , Neutrófilos/patologia , Biomarcadores/sangue , Humanos , Infecções/sangue , Inflamação/sangue , Contagem de Leucócitos
4.
Toxicon ; 56(6): 868-79, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20561540

RESUMO

The cyanobacterial neurotoxin beta-N-methylamino-L-alanine (BMAA) has been associated with certain forms of progressive neurodegenerative disease, including sporadic Amyotrophic Lateral Sclerosis and Alzheimer's disease. Reports of BMAA in cyanobacterial blooms from lakes, reservoirs, and other water resources continue to be made by investigators in a variety of laboratories. Recently it was suggested that during analysis BMAA may be confused with its structural isomer 2,4-diaminobutyric acid (2,4-DAB), or that current detection methods may mistake other compounds for BMAA. We here review the evidence that BMAA can be consistently and reliably separated from 2,4-DAB during reversed-phase HPLC, and that BMAA can be confidently distinguished from 2,4-DAB during triple quadrupole LC-MS/MS analysis by i) different retention times, ii) diagnostic product ions resulting from collision-induced dissociation, and iii) consistent ratios between selected reaction monitoring (SRM) transitions. Furthermore, underivatized BMAA can be separated from 2,4-DAB with an amino acid analyzer with post-column visualization using ninhydrin. Other compounds that may be theoretically confused with BMAA during chloroformate derivatization during GC analysis are distinguished due to their different retention times.


Assuntos
Diamino Aminoácidos/análise , Aminobutiratos/análise , Toxinas Bacterianas/análise , Cianobactérias/química , Neurotoxinas/análise , Cromatografia Líquida de Alta Pressão , Toxinas de Cianobactérias , Isomerismo , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
5.
Ecotoxicol Environ Saf ; 71(2): 309-13, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18538391

RESUMO

Beta-N-methylamino-L-alanine (BMAA) is a neurotoxic non-proteinogenic amino acid reportedly produced by the majority of cyanobacterial isolates. A novel method was developed for the detection of BMAA in biological samples. Cultures representing the taxonomic diversity and geographic distribution in Southern Africa were collected and made uni-algal by standard methods before analysis for the presence of both free and protein-associated BMAA. Protein-associated BMAA was released by acid hydrolysis in an inert atmosphere. Samples were analyzed by gas chromatography-mass spectrometry (GC-MS) with pre-derivatization of amino acids using Phenomonex EZ:faast of the tested cultures, 96% were positive for BMAA although several were below the limit for quantification. BMAA presence was not related to the geographic origin or taxonomy of isolates and no correlation between free and bound BMAA concentrations was observed within or between taxonomic groups. These data offer the first confirmation of the taxonomic and geographic ubiquity of BMAA in freshwater cyanobacteria.


Assuntos
Diamino Aminoácidos/análise , Cianobactérias/química , Diamino Aminoácidos/metabolismo , Cianobactérias/metabolismo , Toxinas de Cianobactérias , Cromatografia Gasosa-Espectrometria de Massas , Sensibilidade e Especificidade , África do Sul
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