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1.
Talanta ; 276: 126237, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38776769

RESUMO

Lysergic acid diethylamide (LSD) and two phenethylamine classes (NBOHs and NBOMes) are the main illicit drugs found in seized blotter papers. The preliminary identification of these substances is of great interest for forensic analysis. In this context, this work constitutes the inaugural demonstration of an efficient methodology for the selective detection of LSD, NBOHs, and NBOMes, utilizing a fully 3D-printed electrochemical double cell (3D-EDC). This novel 3D-EDC enables the use of two working electrodes and/or two supporting electrolytes (at different pHs) in the same detection system, with the possibility of shared or individual auxiliary and pseudo-reference electrodes. Thus, the selective voltammetric detection of these substances is proposed using two elegant strategies: (i) utilizing the same 3D-EDC platform with two working electrodes (boron-doped diamond (BDD) and 3D-printed graphite), and (ii) employing two pH levels (4.0 and 12.0) with 3D-printed graphite electrode. This comprehensive framework facilitates a fast, robust, and uncomplicated electrochemical analysis. Moreover, this configuration enables a rapid and sensitive detection of LSD, NBOHs, and NBOMes in seized samples, and can also provide quantitative analysis. The proposed method showed good stability of the electrochemical response with RSD <9 % for Ip and <5 % for Ep, evaluating all oxidation processes observed for studied analytes (n = 7) at two pH levels, using the same and different (n = 3) working electrodes. It demonstrates a broad linear range (20-100 and 20-70 µmol L-1) and a low LOD (1.0 µmol L-1) for quantification of a model molecule (LSD) at the two pHs studied. Hence, the 3D-EDC combined with voltammetric techniques using BDD and 3D-printed graphite electrodes on the same platform, or only with this last sensor at two pH values, provide a practical and robust avenue for preliminary identification of NBOHs, NBOMes, and LSD. This method embodies ease, swiftness, cost-efficiency, robustness, and selectivity as an on-site screening tool for forensic analysis.


Assuntos
Técnicas Eletroquímicas , Eletrodos , Dietilamida do Ácido Lisérgico , Impressão Tridimensional , Dietilamida do Ácido Lisérgico/análogos & derivados , Dietilamida do Ácido Lisérgico/química , Dietilamida do Ácido Lisérgico/análise , Técnicas Eletroquímicas/métodos , Fenetilaminas/análise , Drogas Ilícitas/análise , Humanos , Limite de Detecção , Grafite/química
2.
Analyst ; 148(7): 1552-1561, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36880972

RESUMO

Mephedrone (MEP) is an illicit stimulant drug that belongs to the synthetic cathinone (SC) class, which has been widely used for recreational purposes and reported in forensic analysis. The preliminary identification of MEP and other SCs in seized samples is of great interest for forensic investigation and a fast and simple screening test for these drugs would be useful for on-site and in-house analyses. In this study, we present the electrochemical detection of MEP in forensic samples using, for the first time, independent redox processes of SCs on a graphene screen-printed electrode (SPE-GP). The proposed method for MEP detection on the SPE-GP was optimized in Britton-Robinson buffer solution (0.1 mol L-1) at pH 10.0 with adsorptive stripping differential pulse voltammetry (AdSDPV). The use of the SPE-GP with AdSDPV provides a wide linear range for MEP determination (2.6 to 112 µmol L-1) with a low limit of detection (LOD) (0.3 µmol L-1). The real surface area available for adsorption on the SPE-GP was estimated to be between 3.80 and 5.70 cm2, which provided high sensitivity for the proposed method. Furthermore, good stability of MEP electrochemical responses on the SPE-GP was obtained using the same or different electrodes (N = 3), with relative standard deviation (RSD) < 5.0% for both redox processes. Interference studies for a common adulterant (caffeine) and twelve other illicit drugs (phenethylamines, amphetamines, and other SCs) were performed with a highly selective response for MEP detection. Therefore, the SPE-GP with AdSDPV is demonstrated to be a selective and sensitive screening method to detect MEP and other SCs in forensic analysis, providing a fast and simple preliminary identification of these drugs in seized samples.


Assuntos
Grafite , Metanfetamina , Catinona Sintética , Eletrodos , Técnicas Eletroquímicas/métodos
4.
Animals (Basel) ; 11(9)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34573521

RESUMO

Canine leishmaniasis (CanL) is a chronic disease caused by Leishmania infantum, and the limitations of the current treatments have encouraged new alternatives, such as the use of immunomodulatory nutrients. The objective of this study was to determine the serum levels of vitamin A (retinol), vitamin D (25(OH)VD3), and zinc (Zn) in dogs with CanL and the effect of in vitro supplementation with the respective active forms ATRA, 1,25(OH)2VD3, and SZn on spleen leukocyte cultures. Serum retinol, 25(OH)VD3, and Zn were determined by HPLC, ELISA, and ICP-MS, respectively. Spleen leukocyte cultures were used for the detection of NO and ROS by flow cytometry; the IFN-γ, TNF-α, and IL-10 levels were determined by ELISA; and the parasite load was determined by microscopy. We detected low serum levels of retinol and Zn and high levels of 25(OH)VD3 in the CanL group. The in vitro supplementation of CanL spleen leukocytes with ATRA, 1,25(OH)2VD3, and SZn, in addition to a soluble leishmania antigen (SLA) treatment, increased the NO and ROS levels, while the treatments with only ATRA and SZn increased the TNF-a levels. Increased IL-10 and IFN-g levels were observed with the addition of SLA to the medium, although the addition of the three nutrients led to a reduction of the IL-10 levels, and the addition of 1,25(OH)2VD3 and SZn led to a reduction of IFN-g. A supplementation with 1,25(OH)2VD3 and SZn reduced the parasite load but only in the absence of SLA. We suggest that the nutrients we tested are involved in the leishmanicidal mechanism, showing a potential for investigation in future studies.

5.
Talanta ; 233: 122597, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215085

RESUMO

1-(3-chlorophenyl) piperazine (mCPP) is a synthetic drug with hallucinogenic effects that has often been found in seized samples. In this context, easy to use point-of-care tests can be of great value in preliminary forensic analysis. Herein, we proposed a simple, fast, and portable electrochemical method for the detection of mCPP in seized samples. The method is based on the use of disposable screen-printed carbon electrodes (SPCE) and rapid screening procedures by square-wave voltammetry using minimal sample sizes (100 µL). mCPP showed an irreversible electrochemical oxidation process at +0.65 V on SPCE (vs Ag) using 0.04 mol L-1 Britton Robinson (BR) buffer solution (pH 7) as the supporting electrolyte. The proposed method exhibited a linear correlation (r = 0.998) between peak current and mCPP concentration in the range of 1-30 µmol L-1 (LOD = 0.1 µmol L-1). Interference studies were performed for adulterants and other classes of drugs of abuse, which can also be found in seized samples containing mCPP, such as caffeine, amphetamine, methamphetamine, 1-benzylpiperazine, 3,4-methylenedioxymethamphetamine, methylone, mephedrone, ethylone and 3, 4-methylenedioxypyrovalerone. The developed method presents great potential as a rapid and simple screening tool to detect mCPP in forensic samples.


Assuntos
N-Metil-3,4-Metilenodioxianfetamina , Anfetaminas , Eletrodos , Piperazinas
6.
Sci Data ; 5: 180171, 2018 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-30129936

RESUMO

MicroRNAs play an important role in the regulation of immune responses. The influence of epigenetic mechanisms, particularly RNA-mediated post-transcriptional regulation of host immune responses has been proven vital following infections by different pathogens, and bacteria can modulated host miRNAs. Global miRNA expression analysis from macrophages infected in vitro with different strains of Leptospira spp was performed using miRNA 4.1 microarray strips. Leptospirosis is a bacterial zoonosis of global importance, responsible for significant morbidity and mortality worldwide. Despite considerable advances, much is yet to be discovered about disease pathogenicity, particularly in regards to host-pathogen interactions. We present here a high-quality dataset examining the microtranscriptome of murine macrophages J774A.1 following 8h of infection with virulent, attenuated and saprophyte strains of Leptospira. Metadata files were submitted to the Gene Expression Omnibus (GEO) repository.


Assuntos
Leptospira , Macrófagos/metabolismo , Macrófagos/microbiologia , MicroRNAs , Animais , Regulação da Expressão Gênica , Leptospira/classificação , Leptospira/genética , Leptospirose/genética , Leptospirose/microbiologia , Camundongos , MicroRNAs/biossíntese , MicroRNAs/genética , Especificidade da Espécie
7.
Vet Parasitol ; 202(3-4): 313-8, 2014 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-24703254

RESUMO

Visceral Leishmaniasis (VL) is caused by intracellular parasites of the genus Leishmania that affect humans and several animal species. Dogs are one of the main urban reservoirs of the parasite and play a central role in the transmission cycle to humans via sandflies. Studies concerning the immune response in dogs with VL have demonstrated that protective immunity is associated with cellular immune response, while disease progression is associated with humoral response and IL-10 and TGF-ß production. The study aimed to evaluate IL-10 and TGF-ß production by regulatory T (Treg) cells in the blood and spleen of dogs naturally infected by Leishmania spp. and correlate this with parasite load. Five healthy dogs and 29 dogs with proven infection were selected for the study group. Real-time PCR was used to quantify parasite load and confirm infection by Leishmania spp. Treg cells producing IL-10 and TGF-ß were quantified using flow cytometry. An increase in IL-10 production by Treg cells was verified in the spleen of dogs naturally infected by Leishmania spp. Concurrently, a decrease in the total number of T cells in these dogs was verified compared with healthy dogs. No association was determined between parasite load and the percentage of spleen Treg cells producing IL-10 and TGF-ß. These findings suggest that Treg cells are an important source of IL-10 in the spleen, participating in immune response modulation, while the reduced percentage of these cells in infected dogs could be attributed to persistent immune activation.


Assuntos
Doenças do Cão/imunologia , Fatores de Transcrição Forkhead/metabolismo , Interleucina-10/metabolismo , Leishmaniose Visceral/veterinária , Baço/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Doenças do Cão/sangue , Cães , Ensaio de Imunoadsorção Enzimática , Feminino , Leishmaniose Visceral/imunologia , Masculino , Carga Parasitária , Baço/parasitologia , Fator de Crescimento Transformador beta/metabolismo
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