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1.
Appl Microbiol Biotechnol ; 103(17): 7203-7215, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31256229

RESUMO

Since polycyclic aromatic hydrocarbons (PAHs) are mutagenic, teratogenic, and carcinogenic, they are of considerable environmental concern. A biotechnological approach to remove such compounds from polluted ecosystems could be based on the use of white-rot fungi (WRF). The potential of well-adapted indigenous Ganoderma strains to degrade PAHs remains underexplored. Seven native Ganoderma sp. strains with capacity to produce high levels of laccase enzymes and to degrade synthetic dyes were investigated for their degradation potential of PAHs. The crude enzymatic extracts produced by Ganoderma strains differentially degraded the PAHs assayed (naphthalene 34-73%, phenanthrene 9-67%, fluorene 11-64%). Ganoderma sp. UH-M was the most promising strain for the degradation of PAHs without the addition of redox mediators. The PAH oxidation performed by the extracellular enzymes produced more polar and soluble metabolites such as benzoic acid, catechol, phthalic and protocatechuic acids, allowing us to propose degradation pathways of these PAHs. This is the first study in which breakdown intermediates and degradation pathways of PAHs by a native strain of Ganoderma genus were determined. The treatment of PAHs with the biomass of this fungal strain enhanced the degradation of the three PAHs. The laccase enzymes played an important role in the degradation of these compounds; however, the role of peroxidases cannot be excluded. Ganoderma sp. UH-M is a promising candidate for the bioremediation of ecosystems polluted with PAHs.


Assuntos
Poluentes Ambientais/metabolismo , Ganoderma/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Biodegradação Ambiental , Fluorenos/metabolismo , Ganoderma/enzimologia , Lacase/metabolismo , Naftalenos/metabolismo , Oxirredução , Peroxidases/metabolismo , Fenantrenos/metabolismo
2.
Oncotarget ; 10(14): 1407-1424, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30858926

RESUMO

Worldwide, cytoreductive surgery (CRS) and hyperthermic intraperitoneal perioperative chemotherapy (HIPEC) are used in current clinical practice for colorectal peritoneal surface malignancy (PSM) treatment. Although, there is an acknowledged standardization regarding the CRS, we are still lacking a much-needed standardization amongst the various intraperitoneal (IP) chemotherapy protocols, including the HIPEC dosing regimen. We should rely on pharmacologic evidence building towards such a standardization. The current IP chemotherapy dosing regimens can be divided into body surface area (BSA)-based and concentration-based protocols. A preclinical animal study was designed to evaluate pharmacologic advantage (PA), efficacy and survival. WAG/Rij rats were IP injected with the rat colonic carcinoma cell line CC-531. Animals were randomized into three groups: CRS alone or CRS combined with oxaliplatin-based HIPEC (either BSA- or concentration-based). There was no difference in PA between the two groups (p=0.283). Platinum concentration in the tumor nodule was significantly higher in the concentration-based group (p<0.001). Median survival did not differ between the treatment groups (p<0.250). This preclinical study, in contrast to previous thinking, clearly demonstrates that the PA does not provide any information about the true efficacy of the drug and emphasizes the importance of the tumor nodule as pharmacologic endpoint.

3.
J Surg Oncol ; 119(7): 999-1010, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30838646

RESUMO

BACKGROUND AND OBJECTIVES: Cytoreductive surgery (CRS) and hyperthermic intraperitoneal perioperative chemotherapy (HIPEC) are the standard of care for patients diagnosed with colorectal peritoneal surface malignancy (PSM). Despite a clearly defined standardization of CRS, a large variety of HIPEC modalities are still used in clinical practice. METHODS: Body surface area (BSA)- and concentration-based HIPEC protocols were clinically and pharmacologically evaluated in a randomized phase III clinical pilot trial. Oxaliplatin dose was 460 mg/m 2 (BSA-based) in 2 L/m 2 carrier solution (concentration-based). Platinum quantification was performed using a validated inductively coupled plasma mass spectrometry method. Three-month morbidity, mortality, and health-related quality of life (HRQOL) were assessed. RESULTS: Thirty-one patients were randomized to either BSA- or concentration-based HIPEC. Toxicity and efficacy were higher (P < 0.001) in patients receiving concentration-based HIPEC. There was no difference in pharmacologic advantage between the two groups. A higher drug concentration in the tumor nodule at the end of HIPEC was found in the HIPEC-concentration group. There was no difference in major morbidity and mortality between the treatment groups. HRQOL was decreased 3 months postoperatively in the HIPEC-concentration group. CONCLUSION: Concentration-based chemotherapy delivers the drug in the most standardized way to the tumor nodule, resulting in increasing drug concentrations in the tumor nodule without increasing major morbidity.


Assuntos
Neoplasias Colorretais/terapia , Hipertermia Induzida/métodos , Oxaliplatina/administração & dosagem , Idoso , Líquido Ascítico/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/cirurgia , Procedimentos Cirúrgicos de Citorredução/métodos , Feminino , Fluoruracila/administração & dosagem , Humanos , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Oxaliplatina/sangue , Oxaliplatina/farmacocinética , Oxaliplatina/urina , Assistência Perioperatória/métodos , Projetos Piloto , Qualidade de Vida
4.
Appl Spectrosc ; 73(1): 67-77, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30226076

RESUMO

Raman spectroscopy and micro-Raman mapping have been used to study the distribution of different chemical components at the surface of coated papers. The paper coatings contain organic nanoparticles with a structure of poly(styrene- co-maleimide) and encapsulated vegetable oils. Raman spectroscopy is able to differentiate between various types of oil, i.e., polyunsaturated, monounsaturated, or saturated, and indicates that the degree of imidization and reactivity of the oil (amount of free oil) complement each other. The surface mapping over large areas (5 × 5 mm2) illustrates good homogeneity of the coating layer and even surface coverage. The imide and oil are homogeneously distributed within the coating itself without a tendency for agglomeration. The covered areas of imide and oil mostly overlap for polyunsaturated oils, while larger amounts of oil occur outside the imide zones for monounsaturated and saturated oils. The latter indicates that the oil is partly "free" within the coating and acts as a continuous binder phase. The surface mapping over smaller areas (1 × 1 mm2) shows the coating and cellulose covered areas are complementary. The surface maps confirm that interaction between the coating and paper substrate happens through hydrogen bonding. Heterogeneities in the coating are due to the presence of remaining ammonolyzed maleic anhydride precursors forming amic acid moieties. The organic phase, oil phase, and cellulose substrate can also be differentiated by principal component analysis of the surface maps.

5.
J Pharm Biomed Anal ; 152: 39-46, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29414017

RESUMO

Oxaliplatin is a platinum (Pt)1 containing antineoplastic agent that is applied in current clinical practice for the treatment of colon and appendiceal neoplasms. A fully validated, highly sensitive, high throughput inductively coupled plasma mass spectrometry (ICP-MS) method is provided to quantify the total Pt content in plasma, plasma ultrafiltrate, urine and peritoneal fluid. In this ICP-MS approach, the only step of sample preparation is a 1000-fold dilution in 0.5% nitric acid, allowing the analysis of 17 samples per hour. Detection of Pt was achieved over a linear range of 0.01-100 ng/mL. The limit of quantification was 18.0 ng/mL Pt in plasma, 8.0 ng/mL in ultrafiltrate and 6.1 ng/mL in urine and peritoneal fluid. The ICP-MS method was further validated for inter-and intraday precision and accuracy (≤15%), recovery, robustness and stability. Short-term storage of the biofluids, for 14 days, can be performed at -4 °C, -24 °C and -80 °C. As to long-term stability, up to 5 months, storage at -80 °C is encouraged. Furthermore, a timeline assessing the total and unbound Pt fraction in plasma and ultrafiltrate over a period of 45 h is provided. Following an incubation period of 5 h at 37 °C, 19-21% of Pt was recovered in the ultrafiltrate, emphasizing the extensive and rapid binding of oxaliplatin-derived Pt to plasma proteins. The described method can easily be implemented in a routine setting for pharmacokinetic studies in patients treated with oxaliplatin-based hyperthermic intraperitoneal perioperative chemotherapy.


Assuntos
Líquido Ascítico/química , Compostos Organoplatínicos/sangue , Compostos Organoplatínicos/urina , Plasma/química , Antineoplásicos/sangue , Antineoplásicos/urina , Humanos , Espectrometria de Massas/métodos , Oxaliplatina , Estudos Prospectivos , Ultrafiltração/métodos
6.
Plant Physiol Biochem ; 83: 1-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25049163

RESUMO

This study aims to uncover the spatiotemporal involvement of glutathione (GSH) in two major mechanisms of cadmium (Cd)-induced detoxification (i.e. chelation and antioxidative defence). A kinetic study was conducted on hydroponically grown Arabidopsis thaliana (L. Heyhn) to gain insight into the early events after exposure to Cd. Cadmium detoxification was investigated at different levels, including gene transcripts, enzyme activities and metabolite content. Data indicate a time-dependent response both within roots and between plant organs. Early on in roots, GSH was preferentially allocated to phytochelatin (PC) synthesis destined for Cd chelation. This led to decreased GSH levels, without alternative pathways activated to complement GSH's antioxidative functions. After one day however, multiple antioxidative pathways increased including superoxide dismutase (SOD), ascorbate (AsA) and catalase (CAT) to ensure efficient neutralization of Cd-induced reactive oxygen species (ROS). As a consequence of Cd retention and detoxification in roots, a delayed response occurred in leaves. Together with high leaf thiol contents and possibly signalling responses from the roots, the leaves were protected, allowing them sufficient time to activate their defence mechanisms.


Assuntos
Antioxidantes/metabolismo , Arabidopsis/efeitos dos fármacos , Cádmio/toxicidade , Glutationa/metabolismo , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Arabidopsis/metabolismo , Peróxido de Hidrogênio/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Compostos de Sulfidrila/metabolismo , Superóxido Dismutase/metabolismo
7.
Eur J Pharm Biopharm ; 81(1): 230-7, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22269939

RESUMO

The aim was to evaluate near-infrared spectroscopy for the in-line determination of the drug concentration, the polymer-drug solid-state behaviour and molecular interactions during hot-melt extrusion. Kollidon® SR was extruded with varying metoprolol tartrate (MPT) concentrations (20%, 30% and 40%) and monitored using NIR spectroscopy. A PLS model allowed drug concentration determination. The correlation between predicted and real MPT concentrations was good (R(2)=0.97). The predictive performance of the model was evaluated by the root mean square error of prediction, which was 1.54%. Kollidon® SR with 40% MPT was extruded at 105°C and 135°C to evaluate NIR spectroscopy for in-line polymer-drug solid-state characterisation. NIR spectra indicated the presence of amorphous MPT and hydrogen bonds between drug and polymer in the extrudates. More amorphous MPT and interactions could be found in the extrudates produced at 135°C than at 105°C. Raman spectroscopy, DSC and ATR FT-IR were used to confirm the NIR observations. Due to the instability of the formulation, only in-line Raman spectroscopy was an adequate confirmation tool. NIR spectroscopy is a potential PAT-tool for the in-line determination of API concentration and for the polymer-drug solid-state behaviour monitoring during pharmaceutical hot-melt extrusion.


Assuntos
Metoprolol/química , Modelos Estatísticos , Povidona/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Varredura Diferencial de Calorimetria , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos , Estabilidade de Medicamentos , Temperatura Alta , Ligação de Hidrogênio , Análise dos Mínimos Quadrados , Polímeros/química , Análise Espectral Raman
8.
Environ Health ; 10: 77, 2011 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-21888673

RESUMO

BACKGROUND: Urinary kidney injury molecule 1 is a recently discovered early biomarker for renal damage that has been proven to be correlated to urinary cadmium in rats. However, so far the association between urinary cadmium and kidney injury molecule 1 in humans after long-term, low-dose cadmium exposure has not been studied. METHODS: We collected urine and blood samples from 153 non-smoking men and women aged 60+, living in an area with moderate cadmium pollution from a non-ferrous metal plant for a significant period. Urinary cadmium and urinary kidney injury molecule 1 as well as other renal biomarkers (alpha1-microglobulin, beta2-microglobulin, blood urea nitrogen, urinary proteins and microalbumin) were assessed. RESULTS: Both before (r = 0.20; p = 0.01) and after (partial r = 0.32; p < 0.0001) adjustment for creatinine, age, sex, past smoking, socio-economic status and body mass index, urinary kidney injury molecule 1 correlated with urinary cadmium concentrations. No significant association was found between the other studied renal biomarkers and urinary cadmium. CONCLUSIONS: We showed that urinary kidney injury molecule 1 levels are positively correlated with urinary cadmium concentration in an elderly population after long-term, low-dose exposure to cadmium, while other classical markers do not show an association. Therefore, urinary kidney injury molecule 1 might be considered as a biomarker for early-stage metal-induced kidney injury by cadmium.


Assuntos
Cádmio/toxicidade , Cádmio/urina , Exposição Ambiental , Nefropatias/induzido quimicamente , Rim/patologia , Glicoproteínas de Membrana/urina , Idoso , Albuminas/análise , alfa-Globulinas/urina , Bélgica , Biomarcadores/análise , Biomarcadores/urina , Nitrogênio da Ureia Sanguínea , Creatinina/urina , Feminino , Receptor Celular 1 do Vírus da Hepatite A , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Proteinúria/urina , Receptores Virais , Microglobulina beta-2/urina
9.
Int J Phytoremediation ; 13(3): 244-55, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21598790

RESUMO

The aim was to investigate if engineered endophytes that are capable of degrading organic contaminants, and deal with or ideally improve uptake and translocation of toxic metals, can improve phytoremediation of mixed organic-metal pollution. As a model system, yellow lupine was inoculated with the endophyte Burkholderia cepacia VM1468 possessing (a) the pTOM-Bu61 plasmid, coding for constitutive toluene/TCE degradation, and (b) the chromosomally inserted ncc-nre Ni resistance/sequestration system. As controls, plants were inoculated with B. vietnamiensis BU61 (pTOM-Bu61) and B. cepacia BU72 (containing the ncc-nre Ni resistance/sequestration system). Plants were exposed to mixes of toluene and Ni. Only inoculation with B. cepacia VM1468 resulted in decreased Ni and toluene phytotoxicity, as measured by a protective effect on plant growth and decreased activities of enzymes involved in antioxidative defence (catalase, guaiacol peroxidase, superoxide dismutase) in the roots. Besides, plants inoculated with B. cepacia VM1468 and B. vietnamiensis BU61 released less toluene through the leaves than non-inoculated plants and those inoculated with B. cepacia BU72. Ni-uptake in roots was slightly increased for B. cepacia BU72 inoculated plants. These results indicate that engineered endophytes have the potential to assist their host plant to deal with co-contamination of toxic metals and organic contaminants during phytoremediation.


Assuntos
Burkholderia cepacia/metabolismo , Lupinus/metabolismo , Lupinus/microbiologia , Níquel/metabolismo , Tolueno/metabolismo , Biodegradação Ambiental , Burkholderia/isolamento & purificação , Burkholderia/metabolismo , Burkholderia cepacia/isolamento & purificação , Lupinus/efeitos dos fármacos , Lupinus/crescimento & desenvolvimento , Níquel/toxicidade , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Tolueno/toxicidade , Tricloroetileno/metabolismo
10.
J Chromatogr A ; 1210(2): 212-21, 2008 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-18922540

RESUMO

Thermal extraction-GC-MS (TE-GC-MS) is a relatively new analytical technique which demonstrates a large potential for the analysis of various solid matrices. This technique provides a rapid quantitative and simultaneous determination of a wide range of volatile and semi-volatile organic compounds without laborious sample preparation or any chemical pre-treatment. Its amenability to automation and coupling with on-line detection methods makes TE-GC-MS a promising technique, not only in laboratory analysis, but also for in situ emission monitoring. However, the number of studies dedicated to the application of TE-GC-MS to fly ashes, which are an unavoidable by-product of any thermal industrial process and also the sink of many environmental pollutants, is limited. The ability of TE-GC-MS to analyse a wide range of trace semi-volatile dioxin surrogate compounds in fly ash samples is investigated as an alternative to the well-established solvent extraction-GC-MS analysis (SE-GC-MS). Reproducibility, the effect of TE temperature, time, flow, and the influence of the analysed matrix are studied. Dedicated experiments demonstrate that the conversion (dechlorination and in situ formation) of target analytes and the decomposition of the fly ash matrix can take place at elevated TE temperatures and during prolonged TE times. Moreover, these effects are matrix-specific and vary from sample to sample. After optimizing the TE parameters, two fly ash samples of different origins are analysed and more than 50 individual analytes representing different classes of aromatic compounds are quantified and compared with those available from the SE-GC-MS analysis.


Assuntos
Carbono/química , Dioxinas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Material Particulado/química , Cinza de Carvão , Dioxinas/antagonistas & inibidores , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Temperatura Alta , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de Tempo
11.
Environ Res ; 103(1): 30-7, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16843453

RESUMO

Contaminated soil particles and food are established routes of exposure. We investigated the relations between biomarkers of exposure to cadmium and lead, and the metal loading rates in house dust in the adult residents of an area with a soil cadmium concentration of > or = 3 mg/kg (n=268) and a reference area (n=205). We determined the metal concentrations in house dust allowed to settle for 3 months in Petri dishes placed in the participants' bedrooms. The continuously distributed vegetable index was the first principal component derived from the metal concentrations in six different vegetables. The biomarkers of exposure (blood cadmium 9.2 vs. 6.2 nmol/L; 24-h urinary cadmium 10.5 vs. 7.0 nmol; blood lead 0.31 vs. 0.24 micromol/L), the loading rates of cadmium and lead in house dust (0.29 vs. 0.12 and 7.52 vs. 3.62 ng/cm(2)/92 days), and the vegetable indexes (0.31 vs. -0.44 and 0.13 vs. -0.29 standardized units) were significantly higher in the contaminated area. A two-fold increase in the metal loading rate in house dust was associated with increases (P<0.001) in blood cadmium (+2.3%), 24-h urinary cadmium (+3.0%), and blood lead (+2.0%), independent of the vegetable index and other covariates. The estimated effect sizes on the biomarkers of internal exposure were three times greater for house dust than vegetables. In conclusion, in the adult population, house dust is potentially an important route of exposure to heavy metals in areas with contaminated soils, and should be incorporated in the assessment of health risks.


Assuntos
Cádmio/análise , Poeira/análise , Chumbo/análise , Poluentes do Solo/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Bélgica , Biomarcadores , Cádmio/sangue , Cádmio/urina , Monitoramento Ambiental , Feminino , Ferritinas/sangue , Contaminação de Alimentos/análise , Habitação , Humanos , Chumbo/sangue , Masculino , Pessoa de Meia-Idade , Poluentes do Solo/sangue , Poluentes do Solo/urina , Verduras/química
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