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1.
Anal Chem ; 96(18): 6875-6880, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38651263

RESUMO

Here, we present the proof-of-concept of a lateral flow assay (LFA) that is capable of detecting small-molecule targets in a noncompetitive manner by deploying a sandwich-type format based on the aptamer kissing complex (AKC) strategy. A fluorescently labeled hairpin aptamer served as the signaling agent, while a specific RNA hairpin grafted onto the strip served as the capture element. The hairpin aptamer switched from an unfolded to a folded form in the presence of the target, resulting in kissing interactions between the loops of the reporter and the capture agents. This design triggered a target-dependent fluorescent signal at the test line. The AKC-based LFA was developed for the detection of adenosine, achieving a detection limit in the micromolar range. The assay revealed the presence of the same analyte in urine. The method also proved effective with another small molecule (theophylline). We believe that the AKC-based LFA approach could overcome many of the shortcomings associated with conventional signal-off methods and competitive processes.


Assuntos
Adenosina , Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Aptâmeros de Nucleotídeos/química , Adenosina/análise , Adenosina/urina , Técnicas Biossensoriais/métodos , Humanos , Teofilina/análise , Teofilina/urina , Limite de Detecção , Corantes Fluorescentes/química
2.
Int J Mol Sci ; 22(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34638987

RESUMO

Glioblastoma (GBM) is the most aggressive malignant glioma, with a very poor prognosis; as such, efforts to explore new treatments and GBM's etiology are a priority. We previously described human GBM cells (R2J-GS) as exhibiting the properties of cancer stem cells (growing in serum-free medium and proliferating into nude mice when orthotopically grafted). Sodium selenite (SS)-an in vitro attractive agent for cancer therapy against GBM-was evaluated in R2J-GS cells. To go further, we launched a preclinical study: SS was given orally, in an escalation-dose study (2.25 to 10.125 mg/kg/day, 5 days on, 2 days off, and 5 days on), to evaluate (1) the absorption of selenium in plasma and organs (brain, kidney, liver, and lung) and (2) the SS toxicity. A 6.75 mg/kg SS dose was chosen to perform a tumor regression assay, followed by MRI, in R2J-GS cells orthotopically implanted in nude mice, as this dose was nontoxic and increased brain selenium concentration. A group receiving TMZ (5 mg/kg) was led in parallel. Although not reaching statistical significance, the group of mice treated with SS showed a slower tumor growth vs. the control group (p = 0.08). No difference was observed between the TMZ and control groups. We provide new insights of the mechanisms of SS and its possible use in chemotherapy.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Corpo Estriado/cirurgia , Glioblastoma/tratamento farmacológico , Células-Tronco Neoplásicas/transplante , Selenito de Sódio/efeitos adversos , Oligoelementos/efeitos adversos , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Animais , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Corpo Estriado/metabolismo , Glioblastoma/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Selênio/metabolismo , Selenito de Sódio/administração & dosagem , Temozolomida/administração & dosagem , Oligoelementos/administração & dosagem , Resultado do Tratamento
3.
Angew Chem Int Ed Engl ; 60(22): 12346-12350, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-33742515

RESUMO

We introduced an aptamer switch design that relies on the ability of post-transition/transition metal ions to trigger, through their coordination to nucleobases, substantial DNA destabilization. In the absence of molecular target, the addition of one such metal ion to usual aptamer working solutions promotes the formation of an alternative, inert DNA state. Upon exposure to the cognate compound, the equilibrium is shifted towards the competent DNA form. The switching process was preferentially activated by metal ions of intermediate base over phosphate complexation preference (i.e. Pb2+ , Cd2+ ) and operated with diversely structured DNA molecules. This very simple aptamer switch scheme was applied to the detection of small organics using the fluorescence anisotropy readout mode. We envision that the approach could be adapted to a variety of signalling methods that report on changes in the surface charge density of DNA receptors.

4.
J Inherit Metab Dis ; 43(5): 944-951, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32392388

RESUMO

Many similarities between tryptophan (Trp) and phenylalanine (Phe) metabolisms exist. It is possible that a modification of Trp metabolism might be seen in phenylketonuria (PKU). As some of these metabolites have neuroactive properties, they should be consider in neurological impairment seen in this pathology and not totally explained by blood Phe concentrations. One hundred and fifty-one adult PKU patients (mean age 26.8 years) were included for this study. Plasma Trp, kynurenine (KYN), 3-hydroxykynurenic acid (3HK), and kynurenic acid (KA) were analyzed by liquid chromatography coupled with tandem mass spectrometry. KYN and 3HK were significantly lower in PKU patients compared to general population (P < .0001), and KA was significantly enhanced is this population (P = .009). Furthermore, 3HK concentration was significantly different between PKU patients underwent controlled low-Phe diet compared to PKU patients without this diet (P = .0016). In PKU patients with diet, taking AA substitute enable higher plasma 3HK concentration than without (P = .0008) but still not reaching general population level (P < .0001). Although further study has to be done, it is clear that Trp metabolism is modified in adult PKU patients. An exploration of complete Trp metabolism, and not only Trp concentration, is needed in PKU population, but also in other inborn error of metabolism treated with hypoprotidic diet.


Assuntos
Fenilcetonúrias/sangue , Triptofano/metabolismo , Adulto , Análise Química do Sangue/métodos , Cromatografia Líquida , Feminino , França , Humanos , Masculino , Fenilcetonúrias/diagnóstico , Fenilcetonúrias/metabolismo , Estudos Prospectivos , Espectrometria de Massas em Tandem
5.
Br J Nutr ; 122(2): 186-194, 2019 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-31006386

RESUMO

The aim of this study was to assess the validity of the predictive INTERSALT equation using spot urine samples to estimate 24-h urinary Na (24-hUNa) excretion and daily Na intake among the French adult population. Among 193 French adults ('validation sample'), we assessed the validity by comparing predicted 24-hUNa excretion from spot urine and measured 24-hUNa excretion from 24-h urine collections. Spearman correlation coefficients and Bland-Altman plots were used and we calculated calibration coefficients. In a nationally representative sample of 1720 French adults ('application sample'), the calibrated predictive equation was then applied to the spot urine Na values to estimate 24-hUNa excretion and daily Na intake. In that sample, predicted Na intake was compared with that estimated from 24-h dietary recalls. Results were adjusted and corrected using calibration coefficients. In the validation sample, the measured 24-hUNa excretion was on average 14 % higher than the predicted 24-hUNa (+13 % for men and +16 % for women). Correlation between measured and predicted 24-hUNa excretion was moderate (Spearman r 0·42), and the Bland-Altman plots showed underestimation at lower excretion level and overestimation at higher level. In the application study, estimated daily salt intake was 8·0 g/d using dietary recalls, 8·1 g/d using predicted INTERSALT equation and 9·3 g/d after applying calibration coefficients calculated in the validation study. Despite overall underestimation of 24-hUNa excretion by spot urinary Na, the use of predictive INTERSALT equation remains an acceptable alternative in monitoring global Na intake/excreted in the French population but its use is not advised at the individual level.


Assuntos
Sódio na Dieta/administração & dosagem , Sódio/urina , Adulto , Idoso , Dieta , Registros de Dieta , Reações Falso-Negativas , Feminino , França , Humanos , Masculino , Rememoração Mental , Pessoa de Meia-Idade , Inquéritos Nutricionais , Fatores de Tempo , Coleta de Urina/métodos
6.
J Physiol ; 594(6): 1727-40, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26663321

RESUMO

Obstructive sleep apnoea syndrome is characterized by repetitive episodes of upper airway collapse during sleep resulting in chronic intermittent hypoxia (IH). Obstructive sleep apnoea syndrome, through IH, promotes cardiovascular and metabolic disorders. Endothelin-1 (ET-1) secretion is upregulated by IH, and is able to modulate adipocyte metabolism. Therefore, the present study aimed to characterize the role of ET-1 in the metabolic consequences of IH on adipose tissue in vivo and in vitro. Wistar rats were submitted to 14 days of IH-cycles (30 s of 21% FiO2 and 30 s of 5% FiO2 ; 8 h day(-1) ) or normoxia (air-air cycles) and were treated or not with bosentan, a dual type A and B endothelin receptor (ETA-R and ETB-R) antagonist. Bosentan treatment decreased plasma free fatty acid and triglyceride levels, and inhibited IH-induced lipolysis in adipose tissue. Moreover, IH induced a 2-fold increase in ET-1 transcription and ETA-R expression in adipose tissue that was reversed by bosentan. In 3T3-L1 adipocytes, ET-1 upregulated its own and its ETA-R transcription and this effect was abolished by bosentan. Moreover, ET-1 induced glycerol release and inhibited insulin-induced glucose uptake. Bosentan and BQ123 inhibited these effects. Bosentan also reversed the ET-1-induced phosphorylation of hormone-sensitive lipase (HSL) on Ser(660) . Finally, ET-1-induced lipolysis and HSL phosphorylation were also observed under hypoxia. Altogether, these data suggest that ET-1 is involved in IH-induced lipolysis in Wistar rats, and that upregulation of ET-1 production and ETA-R expression by ET-1 itself under IH could amplify its effects. Moreover, ET-1-induced lipolysis could be mediated through ETA-R and activation of HSL by Ser(660) phosphorylation.


Assuntos
Tecido Adiposo/metabolismo , Endotelina-1/metabolismo , Hipóxia/metabolismo , Lipólise , Processamento de Proteína Pós-Traducional , Esterol Esterase/metabolismo , Células 3T3 , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/patologia , Animais , Bosentana , Antagonistas dos Receptores de Endotelina/farmacologia , Endotelina-1/genética , Ácidos Graxos/sangue , Hipóxia/patologia , Masculino , Camundongos , Fosforilação , Ratos , Ratos Wistar , Receptores de Endotelina/genética , Receptores de Endotelina/metabolismo , Sulfonamidas/farmacologia , Triglicerídeos/sangue
7.
Anal Chem ; 88(5): 2570-5, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26832823

RESUMO

We report herein a novel sandwich-type enzyme-linked assay for the "signal-on" colorimetric detection of small molecules. The approach (referred to as enzyme-linked aptamer kissing complex assay (ELAKCA)) relied on the kissing complex-based recognition of the target-bound hairpin aptamer conformational state by a specific RNA hairpin probe. The aptamer was covalently immobilized on a microplate well surface to act as target capture element. Upon small analyte addition, the folded aptamer was able to bind to the biotinylated RNA hairpin module through loop-loop interaction. The formed ternary complex was then revealed by the introduction of the streptavidin-horseradish peroxidase conjugate that catalytically converted the 3,3',5,5'-tetramethylbenzidine substrate into a colorimetric product. ELAKCA was successfully designed for two different systems allowing detecting the adenosine and theophylline molecules. The potential practical applicability in terms of biological sample analysis (human plasma), temporal stability, and reusability was also reported. Owing to the variety of both hairpin functional nucleic acids, kissing motifs, and enzyme-based signaling systems, ELAKCA opens up new prospects for developing small molecule sensing platforms of wide applications.


Assuntos
Ensaios Enzimáticos/métodos , Adenosina/sangue , Aptâmeros de Nucleotídeos/química , Benzidinas/química , Compostos Cromogênicos/química , Colorimetria , Ensaios Enzimáticos/instrumentação , Peroxidase do Rábano Silvestre/química , Humanos , Estreptavidina/química , Teofilina/sangue
8.
Exp Physiol ; 101(11): 1432-1442, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27615447

RESUMO

NEW FINDINGS: What is the central question of this study? This study addresses the relative impact of obesity and intermittent hypoxia in the pathophysiological process of obstructive sleep apnoea by investigating the metabolic, inflammatory and cardiovascular consequences of intermittent hypoxia in lean and obese Zucker rats. What is the main finding and its importance? We found that obesity and intermittent hypoxia have mainly distinct consequences on the investigated inflammatory and cardiometabolic parameters in Zucker rats. This suggests that, for a given severity of sleep apnea, the association of obesity and obstructive sleep apnoea may not necessarily be deleterious. Obstructive sleep apnoea is associated with obesity with a high prevalence, and both co-morbidities are independent cardiovascular risk factors. Intermittent hypoxia (IH) is thought to be the main factor responsible for the obstructive sleep apnoea-related cardiometabolic alterations. The aim of this study was to assess the respective impact of obesity and IH on the inflammatory and cardiometabolic state in rats. Lean and obese Zucker rats were exposed to normoxia or chronic IH, and we assessed metabolic and inflammatory parameters, such as plasma lipids and glucose, serum leptin and adiponectin, liver cytokines, nuclear factor-κB activity and cardiac endothelin-1 levels. Myocardial infarct size was also evaluated following in vitro ischaemia-reperfusion. Circulating lipids, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), leptin and adiponectin levels were higher in obese versus lean rats. Chronic IH did not have a significant impact on metabolic parameters in lean rats. In obese rats, IH increased glycaemia and HOMA-IR. Liver interleukin-6 and tumour necrosis factor-α levels were elevated in lean rats exposed to IH; obesity prevented the increase in interleukin-6 but not in tumour necrosis factor-α. Finally, IH exposure enhanced myocardial sensitivity to infarction in both lean and obese rats and increased cardiac endothelin-1 in lean but not obese rats. In conclusion, this study shows that the dyslipidaemia and insulin resistance induced by obesity of genetic origin does not enhance the deleterious cardiovascular response to IH and may even partly protect against IH-induced inflammation.


Assuntos
Doenças Cardiovasculares/metabolismo , Hipóxia/metabolismo , Inflamação/metabolismo , Obesidade/metabolismo , Adiponectina/metabolismo , Animais , Glicemia/metabolismo , Doenças Cardiovasculares/fisiopatologia , Citocinas/metabolismo , Modelos Animais de Doenças , Endotelina-1/metabolismo , Insulina/metabolismo , Interleucina-6/metabolismo , Leptina/sangue , Lipídeos/sangue , Fígado/metabolismo , Masculino , Miocárdio/metabolismo , NF-kappa B/metabolismo , Ratos , Ratos Zucker , Fator de Necrose Tumoral alfa/metabolismo
9.
J Sci Food Agric ; 96(10): 3462-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26564426

RESUMO

BACKGROUND: Pomegranate peel extract (PPE) contains several compounds with antioxidative properties. PPE added to foods may interact with endogenous antioxidants and promote health. However, little is known about the biochemical mechanisms by which PPE exerts their actions on tissues of biological systems in vivo. The purpose of this study was to determine the effects of PPE on activities of antioxidant enzymes. Mice were used to investigate the effects of PPE on plasma levels of malondialdehyde (MDA), tissue MDA content and activities of superoxide dismutase 1 (SOD1), SOD2 and glutathione peroxidase (GPX) in the small intestine, liver and skeletal muscle - different tissues involved in the digestion, absorption and metabolism of dietary nutrients. Control mice were fed a standard diet, whereas treated mice were fed for 40 days with the standard diet containing 5% or 10% PPE. RESULTS: Mice fed the 10% PPE diet exhibited lower plasma MDA concentrations, reduced content of MDA in the small intestine and liver and higher levels of SOD1 and GPX activities in the small intestine compared to mice fed the control diet. CONCLUSIONS: These findings demonstrate that intake of PPE in diet attenuates small intestine lipid peroxidation and strengthens the first line of small intestine antioxidant defense by enhancing enzymatic antioxidative pathways. PPE is worthy of further study as a therapeutic approach to prevent peroxidative stress-induced gut pathogenesis. © 2015 Society of Chemical Industry.


Assuntos
Antioxidantes/administração & dosagem , Intestino Delgado/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Lythraceae/química , Extratos Vegetais/farmacologia , Animais , Antioxidantes/farmacologia , Dieta , Feminino , Frutas , Glutationa Peroxidase/metabolismo , Intestino Delgado/enzimologia , Fígado/metabolismo , Malondialdeído/sangue , Camundongos , Músculo Esquelético/metabolismo , Extratos Vegetais/administração & dosagem , Superóxido Dismutase/metabolismo
10.
Br J Nutr ; 113(6): 953-62, 2015 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-25772032

RESUMO

New technologies are promising for the use of short-term instruments for dietary data collection; however, innovative tools should be validated against objective biomarkers. The aim of the present study was to investigate the validity of a Web-based, self-administered dietary record (DR) tool using protein, K and Na intakes against 24 h urinary biomarkers (24 h U). Of the total participants, 199 adult volunteers (104 men and 95 women, mean age 50·5 (23-83 years)) of the NutriNet-Santé Study were included in the protocol. They completed three non-consecutive-day DR and two 24 h U on the first and third DR days. Relative differences between reported (DR) and measured (24 h U) intakes were calculated from the log ratio (DR/24 h U) for protein, K and Na intakes: -14·4,+2·6 and -2·1 % for men; and -13·9, -3·7 and -8·3 % for women, respectively. The correlations between reported and true intakes were 0·61, 0·78 and 0·47 for men and 0·64, 0·42 and 0·37 for women for protein, K and Na, respectively. Attenuation factors, that represent attenuation of the true diet-disease relationship due to measurement error (a value closer to 1 indicating lower attenuation), ranged from 0·23 (Na, women) to 0·60 (K, men). We showed that the Web-based DR tool used in the NutriNet-Santé cohort study performs well in estimating protein and K intakes and fairly well in estimating Na intake. Furthermore, three non-consecutive-day DR appear to be valid for estimating usual intakes of protein and K, although caution is advised regarding the generalisability of these findings to other nutrients and general population.


Assuntos
Dieta , Proteínas Alimentares/administração & dosagem , Potássio na Dieta/administração & dosagem , Sódio na Dieta/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/urina , Estudos de Coortes , Dieta/efeitos adversos , Registros de Dieta , Feminino , Humanos , Internet , Masculino , Pessoa de Meia-Idade , Nitrogênio/urina , Avaliação Nutricional , Paris , Potássio/urina , Autorrelato , Sódio/urina , Adulto Jovem
13.
Sensors (Basel) ; 15(10): 25937-67, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-26473874

RESUMO

In this paper, we introduce a geometric method for 3D reconstruction of the exterior environment using a panoramic microwave radar and a camera. We rely on the complementarity of these two sensors considering the robustness to the environmental conditions and depth detection ability of the radar, on the one hand, and the high spatial resolution of a vision sensor, on the other. Firstly, geometric modeling of each sensor and of the entire system is presented. Secondly, we address the global calibration problem, which consists of finding the exact transformation between the sensors' coordinate systems. Two implementation methods are proposed and compared, based on the optimization of a non-linear criterion obtained from a set of radar-to-image target correspondences. Unlike existing methods, no special configuration of the 3D points is required for calibration. This makes the methods flexible and easy to use by a non-expert operator. Finally, we present a very simple, yet robust 3D reconstruction method based on the sensors' geometry. This method enables one to reconstruct observed features in 3D using one acquisition (static sensor), which is not always met in the state of the art for outdoor scene reconstruction. The proposed methods have been validated with synthetic and real data.

14.
J Hepatol ; 61(1): 28-34, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24631902

RESUMO

BACKGROUND & AIMS: Fibrosis blood tests have been validated in chronic hepatitis C. Their diagnostic accuracy is less documented in hepatitis B. The aim of this study was to describe the diagnostic performance of FibroTest®, FibroMeter®, and HepaScore® for liver fibrosis in hepatitis B compared to hepatitis C. METHODS: 510 patients mono-infected with hepatitis B or C and matched on fibrosis stage were included. Blood tests were performed the day of the liver biopsy. Histological lesions were staged according to METAVIR. RESULTS: Fibrosis stages were distributed as followed: F0 n=76, F1 n=192, F2 n=132, F3 n=54, F4 n=56. Overall diagnostic performance of blood tests were similar between hepatitis B and C with AUROC ranging from 0.75 to 0.84 for significant fibrosis, 0.82 to 0.85 for extensive fibrosis and 0.84 to 0.87 for cirrhosis. Optimal cut-offs were consistently lower in hepatitis B compared to hepatitis C, especially for the diagnosis of extensive fibrosis and cirrhosis, with decreased sensitivity and negative predictive values. More hepatitis B than C patients with F ⩾3 were underestimated: FibroTest®: 47% vs. 26%, FibroMeter®: 24% vs. 6%, HepaScore®: 41% vs. 24%, p<0.01. Multivariate analysis showed that hepatitis B (0R 3.4, 95% CI 1.2-19.2, p<0.02) and low γGT (OR 7.3, 95% CI 2.0-27.0, p<0.003) were associated with fibrosis underestimation. CONCLUSION: Overall the diagnostic performance of blood tests is similar in hepatitis B and C. The risk of underestimating significant fibrosis and cirrhosis is however greater in hepatitis B and cannot be entirely corrected by the use of more stringent cut-offs.


Assuntos
Hepatite B Crônica/sangue , Hepatite B Crônica/patologia , Hepatite C Crônica/sangue , Hepatite C Crônica/patologia , Cirrose Hepática/sangue , Cirrose Hepática/patologia , Adulto , Alanina Transaminase/sangue , Feminino , Testes Hematológicos/métodos , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , gama-Glutamiltransferase/sangue
16.
Ann Nutr Metab ; 65(4): 289-98, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25377123

RESUMO

BACKGROUND/AIMS: Low-grade inflammation is an independent risk factor for cardiovascular disease. Relationships between the antioxidant status and inflammatory biomarkers could give new insights into cardiovascular disease prevention. We investigated long-term associations between the antioxidant nutrient (vitamin C, α-tocopherol, ß-carotene) status and C-reactive protein (CRP) in a population-based cohort. METHODS: Subjects included in the French SU.VI.MAX trial study who had available data on baseline (1994-1995) blood nutrient concentrations and CRP measurements 12 years later (2007-2009) were included. Associations between baseline antioxidant circulating concentrations and elevated CRP (>3 mg/l) were investigated in multivariate logistic regression models. Subgroup analyses were performed according to gender, supplementation group of the initial trial, smoking status, and alcohol intake. RESULTS: Serum α-tocopherol (n = 2,060) and vitamin C (n = 1,719) concentrations [odds ratio (OR) and 95% confidence interval (95% CI) quintile 5 vs. 1: OR 1.10 (95% CI 0.71-1.73), p for trend = 0.533, vs. OR 0.79 (95% CI 0.48-1.29), p for trend = 0.121, respectively] were not associated with elevated CRP concentrations. The ß-carotene status (n = 2,048) was inversely associated with elevated CRP [adjusted OR quintile 5 vs. 1: OR 0.61 (95% CI 0.38-0.98), p for trend = 0.01]. Subgroup analyses showed that associations were stronger in women (p for trend = 0.004), never smokers (p for trend = 0.009) and subjects in the supplementation group (p for trend = 0.002). CONCLUSIONS: Our results suggest that the ß-carotene status may be inversely associated with low-grade inflammation in the long term.


Assuntos
Antioxidantes/metabolismo , Proteína C-Reativa/metabolismo , Inflamação/epidemiologia , Ácido Ascórbico/sangue , Estudos de Coortes , Feminino , França/epidemiologia , Humanos , Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , alfa-Tocoferol/sangue , beta Caroteno/sangue
17.
Ann Biol Clin (Paris) ; 81(2): 111-124, 2023 05 16.
Artigo em Francês | MEDLINE | ID: mdl-37184253

RESUMO

Iron is an essential element to the well functionning of the organism and requires careful maintenance of its homeostasis. This is mainly due to hepcidin, a hormone secreted by the liver that controls the flow of iron within the body. It has a hyposideremic action by reducing the expression of ferroportin, the only protein known to this day, which can export iron into the extracellular environment. This has the effect of decreasing intestinal absorption and increasing intracellular retention, especially in macrophages. Hepcidin is stimulated by elevation of iron and inflammation while activation of erythropoiesis inhibits it. Understanding its regulation allows a better understanding of the pathophysiological mechanisms of overload diseases and iron deficiency. Therefore, hepcidin analysis is interesting for the exploration of iron homeostasis. In combination with other biological parameters of iron status, it is possible to find better instructions for therapeutic managements of iron metabolism diseases. Thus, an assaying method by coupling liquid chromatography and tandem mass spectrometry has been implemented at Grenoble University Hospital and the analytical performances of this assay met the laboratory requirements in terms of reliability of the analysis.


Assuntos
Hepcidinas , Ferro , Humanos , Hepcidinas/metabolismo , Homeostase/fisiologia , Fígado/metabolismo , Reprodutibilidade dos Testes
18.
Anal Chim Acta ; 1243: 340840, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36697182

RESUMO

Herein, we report a novel approach for the design of a colorimetric aptasensor, relying on a Dye Salt Aggregation-based Colorimetric Oligonucleotide assay (DYSACO assay). This method is based on the use of an intercalating agent, Nile Blue (NB), whose aggregation capacities (and thus modification of its absorption spectrum) are drastically amplified by adding salts to the working solution. The presence of an aptamer could protect NB from such aggregation process due to its intercalation into double-stranded DNA and/or interaction with nucleobases. In response to the addition of the specific ligand, the competition between NB and the target for binding to the aptamer occurs, resulting in an increase in the dye salt aggregation and then in the blue-to-blank color change of the solution. The proof-of-principle was demonstrated by employing the anti-l-tyrosinamide aptamer and the assay was successfully applied to the trace enantiomer detection, allowing the detection of an enantiomeric impurity down to approximately 2% in a non-racemic sample. Through a reversed mechanism based on the increased capture of NB by DNA upon analyte binding, the sensing platform was further demonstrated for the Hg(II) detection. Water samples of different origin were spiked with Hg(II) analyte at final range concentrations comprised between (0.5-15 µM). An excellent overall recovery of 122 ± 14%; 105 ± 14%; 99 ± 9%; was respectively obtained from river, tap and mineral water, suggesting that the sensor can be used under real sample conditions. The assay was also shown to work for sensing the ochratoxin A and d-arginine vasopressin compounds, revealing its simplicity and generalizability potentialities.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Mercúrio , Nanopartículas Metálicas , Colorimetria/métodos , Nanopartículas Metálicas/química , Técnicas Biossensoriais/métodos , Ouro/química , Cloreto de Sódio , DNA/química , Peptídeos , Cloreto de Sódio na Dieta , Aptâmeros de Nucleotídeos/química
19.
Environ Int ; 173: 107840, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36857904

RESUMO

BACKGROUND: In vitro and toxicological studies have shown that non-persistent environmental chemicals can perturb thyroid hormone homeostasis. Epidemiological studies with improved exposure assessment (i.e., repeated urine samples) are needed to evaluate effects of these compounds, individually or as a mixture, in humans. We studied the associations between prenatal exposure to non-persistent environmental chemicals and neonatal thyroid hormones. METHODS: The study population consisted of 442 mother-child pairs from the French SEPAGES mother-child cohort recruited between July 2014 and July 2017. For each participant, four parabens, five bisphenols, triclosan, triclocarban, benzophenone-3 as well as metabolites of phthalates and of di(isononyl)cyclohexane-1,2-dicarboxylate were assessed in two pools of repeated urine samples (median: 21 spot urines per pool), collected in the 2nd and 3rd trimesters of pregnancy, respectively. Thyroid stimulating hormone (TSH) and total thyroxine (T4) levels were determined in newborns from a heel-prick blood spot. Maternal iodine and selenium were assessed in urine and serum, respectively. Adjusted linear regression (uni-pollutant model) and Bayesian Kernel Machine Regression (BKMR, mixture model) were applied to study overall and sex-stratified associations between chemicals and hormone concentrations. RESULTS: Interaction with child sex was detected for several compounds. Triclosan, three parabens, and one phthalate metabolite (OH-MPHP) were negatively associated with T4 among girls in the uni-pollutant model. BKMR also suggested a negative association between the mixture and T4 in girls, whereas in boys the association was positive. The mixture was not linked to TSH levels, and for this hormone the uni-pollutant model revealed associations with only a few compounds. CONCLUSION: Our study, based on repeated urine samples to assess exposure, showed that prenatal exposure to some phenols and phthalates disturb thyroid hormone homeostasis at birth. Furthermore, both uni-pollutant and mixture models, suggested effect modification by child sex, while, to date underlying mechanisms for such sex-differences are not well understood.


Assuntos
Poluentes Ambientais , Ácidos Ftálicos , Efeitos Tardios da Exposição Pré-Natal , Triclosan , Masculino , Gravidez , Feminino , Humanos , Recém-Nascido , Glândula Tireoide , Parabenos/análise , Triclosan/toxicidade , Teorema de Bayes , Hormônios Tireóideos , Hormônios , Poluentes Ambientais/urina , Tireotropina , Ácidos Ftálicos/toxicidade , Ácidos Ftálicos/urina , Exposição Ambiental/efeitos adversos
20.
Trials ; 24(1): 759, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38012776

RESUMO

BACKGROUND: Endometriosis is a chronic disease characterized by growth of endometrial tissue outside the uterine cavity which could affect 200 million women (The term "woman" is used for convenience. Individuals gendered as man or as nonbinary can also suffer from this disease) worldwide. One of the most common symptoms of endometriosis is pelvic chronic pain associated with fatigue. This pain can cause psychological distress and interpersonal difficulties. As for several chronic diseases, adapted physical activity could help to manage the physical and psychological symptoms. The present study will investigate the effects of a videoconference-based adapted physical activity combined with endometriosis-based education program on quality of life, pain, fatigue, and other psychological symptoms and on physical activity. METHODS: This multicentric randomized-controlled trial will propose to 200 patients with endometriosis to be part of a trial which includes a 6-month program with 45 min to more than 120 min a week of adapted physical activity and/or 12 sessions of endometriosis-based education program. Effects of the program will be compared to a control group in which patients will be placed on a waiting list. All participants will be followed up 3 and 6 months after the intervention. None of the participants will be blind to the allocated trial arm. The primary outcome measure will be quality of life. Secondary outcomes will include endometriosis-related perceived pain, fatigue, physical activity, and also self-image, stereotypes, motivational variables, perceived support, kinesiophobia, basic psychological need related to physical activity, and physical activity barriers. General linear models and multilevel models will be performed. Predictor, moderator, and mediator variables will be investigated. DISCUSSION: This study is one of the first trials to test the effects of a combined adapted physical activity and education program for improving endometriosis symptoms and physical activity. The results will help to improve care for patients with endometriosis. TRIAL REGISTRATION: ClinicalTrials.gov, NCT05831735 . Date of registration: April 25, 2023.


Assuntos
Endometriose , Qualidade de Vida , Masculino , Humanos , Feminino , Endometriose/diagnóstico , Endometriose/terapia , Endometriose/complicações , Exercício Físico , Dor Pélvica/etiologia , Fadiga , Comunicação por Videoconferência , Terapia por Exercício/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
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