Electrochemistry for non-electrochemists: a postgraduate formative projec

The essential guidelines are presented of a postgraduate course on electrochemistry for master studies at the University of Valencia (Spain). This course has been designed for students with a minimal knowledge of electrochemistry. It is based on laboratory experiments that, starting from an initial theoretical core, promotes the in-laboratory discussion of concepts, operations, functional relations, etc. The course, although focused on voltammetric techniques, covers the main concepts and experimental aspects of electrochemistry and particular attention is put to erroneous conceptions regarding fundamental physicochemical concepts and operations (misconceptions) as well as on general aspects of the scientific methodology (meta-conceptions) around this discipline

Development of methodology for the determination of synthetic pharmaceuticals in slimming phytotherapeutic formulations by capillary electrophoresis

Conselho Nacional de Desenvolvimento Científico e TecnológicoThe adulteration of phytotherapeutic formulations used for weight loss with synthetic pharmaceuticals has been increasing in recent years. The cases of adulteration have been reported in the literature, showing that there is a great concern about this problem, which involves the development of analytical methodologies able to detect them. This paper describes the development of a method for the simultaneous determination of amfepramone, fenproporex, sibutramine and fluoxetine by using capillary zone electrophoresis (CZE) with capacitively coupled contactless conductivity detection (C4D) in a homemade capillary electrophoretic system. The optimized conditions for separation of the pharmaceuticals by CZE-C4D were the following: 50 mmol L-1 phosphate buffer (pH 5.0) containing acetonitrile 50% (v/v) as working electrolyte, separation potential of -15 kV, separation temperature of 25 °C, hydrodynamic injection by gravity (20 cm left side elevation for 60 s). The C4D detection was performed by using a homemade detector, which employs a sinusoidal wave generator operating at 600 kHz frequency and 2 Vpp wave amplitude. The CZE-C4D method was validated for the determination of amfepramone, fenproporex, sibutramine and fluoxetine and it was applied to the analysis of phytotherapeutic formulations used for weight loss, which have been purchased in different commercial pharmacies in the city of Santa Maria. This method was fit in the analysis of four synthetic drugs studied, with a wide linear response range (10 to 500 mg L-1), low detection limits (4 to 5 mg L-1), precision (6 to 9 %) and accuracy (95 to 112 %) . The recovery experiments were carried out in the samples and the recovery values ranged between 80 and 120 % for all the studied samples. The developed method showed high sensitivity, selectivity and analytical precision and it can be used for determining these substances as contaminants in herbal natural formulations. It also an important alternative to the federal control agencies due to its simplicity, rapidity and low cost of analysis considering the small quantities of reagents and samples used.A adulteração de formulações fitoterápicas emagrecedoras com fármacos sintéticos tem aumentado muito nos últimos anos. Os casos de adulteração têm sido relatados na literatura, comprovando que existe uma maior preocupação com relação a este problema, o que implica no desenvolvimento de metodologias analíticas capazes de detectá-los. Este trabalho descreve o desenvolvimento de um método para a determinação simultânea de anfepramona, femproporex, sibutramina e fluoxetina empregando eletroforese capilar de zona (CZE) com detecção condutométrica sem contato capacitivamente acoplada (C4D), usando um sistema de eletroforese capilar construído em laboratório. As condições otimizadas para a separação dos fármacos por CZE-C4D foram as seguintes: eletrólito de trabalho tampão fosfato (pH 5,0) 50 mmol.L-1 contendo acetonitrila 50% (v/v), potencial de separação -15 kV, temperatura de separação 25 °C, injeção hidrodinâmica por gravidade com altura de injeção de 20 cm durante 60 s. A detecção por C4D foi realizada usando um detector construído em laboratório, que emprega um gerador de onda senoidal operando a uma freqüência de 600 kHz e amplitude de onda de 2 Vpp. O método de CZE-C4D foi validado para a determinação de anfepramona, femproporex, sibutramina e fluoxetina e empregado na análise de formulações fitoterápicas emagrecedoras adquiridas em diferentes farmácias de manipulação na cidade de Santa Maria. Este método mostrou-se adequado na análise dos quatro fármacos sintéticos estudados, apresentando uma ampla faixa linear de trabalho (10 a 500 mg L-1), baixos limites de detecção (4 a 5 mg L-1), precisão (6 a 9%) e exatidão (95 a 112%). Os ensaios de recuperação realizados promoveram recuperações entre 80 e 120% para os fármacos sintéticos estudados. O método desenvolvido apresentou alta sensibilidade, seletividade e precisão analítica, podendo ser empregado na determinação destas substâncias como adulterantes em formulações fitoterápicas, tornando-se uma alternativa para órgãos fiscalizadores devido a sua simplicidade, rapidez e baixo custo de análise devido às quantidades reduzidas de reagentes e amostras utilizadas

CCL18 as a Biomarker of Interstitial Lung Disease (ILD) and Progressive Fibrosing ILD in Patients with Idiopathic Inflammatory Myopathies

Objectives: To assess CCL18 and OX40L as biomarkers of interstitial lung disease (ILD) and/or progressive fibrosing (PF-) ILD in idiopathic inflammatory myopathies (IIMs). Methods: Patients with IIMs seen in our center from July 2020 to March 2021 were consecutively enrolled. ILD was detected by high-resolution CT. CCL18 and OX40L serum levels were measured by validated ELISA assays in 93 patients and 35 controls. At the 2-year follow-up, PF-ILD was evaluated according to the INBUILD criteria. Results: ILD was diagnosed in 50 (53.7%) patients. CCL18 serum levels were higher in IIMs patients vs. controls (232.9 [IQR 134.7-399.07] vs. 48.4 [29.9-147.5], p < 0.0001), with no difference for OX40L. IIMs-ILD patients exhibited higher levels of CCL18 than those without ILD (306.8 [190.8-520.5] vs. 162 [75.4-255.8], p < 0.0001). High CCL18 serum levels were independently associated with IIMs-ILD diagnosis. At follow-up, 22/50 (44%) patients developed a PF-ILD. Patients who developed PF-ILD had higher CCL18 serum levels than non-progressors (511 [307-958.7] vs. 207.1 [149.3-381.7], p < 0.0001). Multivariate logistic regression analysis revealed CCL18 as the only independent predictor of PF-ILD (OR 1.006 [1.002-1.011], p = 0.005). Conclusions: Although in a relatively small sample, our data suggest that CCL18 is a useful biomarker in IIMs-ILD, particularly in the early identification of patients at risk of developing PF-ILD

Determinação simultânea de cátions empregando eletroforese capilar com detecção condutométrica sem contato em equipamento construído em laboratório

This work describes the development of a home-made capillary electrophoresis (CE) system based on the capacitively coupled contactless conductivity detection (C4D) for the separation of the metallic species Zn2+, Cr3+, Pb2+, Cd2+, Co2+, Cu2+, Ni2+ e Tl+. A background electrolyte composed of MES/Histidine 0,02 mol L-1 (pH 5.0) was optimized for the separation of the metallic species by using organic solvents and complexing agents as additives. The system allowed the determination of the metallic species using MES/Histidine 0,02 mol L-1 and methanol 5% (pH 5.0) as a background electrolyte, 15 kV separation voltage and hydrodynamic injection by gravity

Transcriptional network profile on synovial fluid T cells in psoriatic arthritis

The objective of the study was to quantify the transcriptional profile, as the main T cell lineage-transcription factors on synovial fluid (SF) T cells, in relation to SF cytokines and T cell frequencies (%) of psoriatic arthritis (PsA) patients. Reverse phase protein array was employed to identify interleukin (IL)-23Rp19-, FOXP3- and related orphan receptor gamma T (ROR\u3b3t)- protein and Janus associated tyrosine kinases 1 (JAK1), signal transducer and activator and transcription 1 (STAT1), STAT3 and STAT5 phosphoproteins in total T cell lysates from SF of PsA patients. IL-1\u3b2, IL-2, IL-6, IL-21 and interferon (INF)-\u3b3 were measured using a multiplex bead immunoassay in SF from PsA patients and peripheral blood (PB) from healthy controls (HC). Frequencies of CD4(+)CD25(-), CD4(+)CD25(high) FOXP3(+) and CD4(+)CD25(high) CD127(low) Treg, and either mean fluorescence intensity (MFI) of FOXP3(+) on CD4(+) Treg or MFI of classic IL-6 receptor (IL-6R) \u3b1 expression on CD4(+)CD25(-) helper/effector T cells (Th/eff) and Treg cells, were quantified in SF of PsA patients and in PB from HC by flow cytometry (FC). In PsA SF samples, IL-2, IL-21 and IFN-\u3b3 were not detectable, whereas IL-6 and IL-1\u3b2 levels were higher than in SF of non-inflammatory osteoarthritis patients. Higher levels of IL-23R-, FOXP3- and ROR\u3b3t proteins and JAK1, STAT1, STAT3 and STAT5 were found in total T cells from SF of PsA patients compared with PB from HC. Direct correlations between JAK1 Y1022/Y1023 and STAT5 Y694, and STAT3 Y705 and IL6, were found in SF of PsA patients. Increased proportion of CD4(+)CD25(high) FOXP3(+) and CD4(+)CD25(high) CD127(low) Treg cells and brighter MFI of IL-6R\u3b1 were observed both on CD4(+)CD25(high)- and CD4(+)CD25(-) T cells in PsA SF. The study showed a distinctive JAK1/STAT3/STAT5 transcriptional network on T cells in the joint microenvironment, outlining the interplay of IL-6, IL-23, IL-1\u3b2 and \u3b3C cytokines in the polarization and plasticity of Th17 and Treg cells, which might participate in the perpetuation of joint inflammation in PsA patients