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1.
Arch Toxicol ; 98(3): 779-790, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38224356

RESUMO

Hair analysis is a crucial method in forensic toxicology with potential applications in revealing doping histories in sports. Despite its widespread use, knowledge about detectable substances in hair is limited. This study systematically assessed the detectability of prohibited substances in sports using a multifaceted approach. Initially, an animal model received a subset of 17 model drugs to compare dose dependencies and detection windows across different matrices. Subsequently, hair incorporation data from the animal experiment were extrapolated to all substances on the World Anti-Doping Agency's List through in-silico prediction. The detectability of substances in hair was further validated in a proof-of-concept human study involving the consumption of diuretics and masking agents. Semi-quantitative analysis of substances in specimens was performed using ultra-performance liquid chromatography-tandem mass spectrometry. Results showed plasma had optimal dose dependencies with limited detection windows, while urine, faeces, and hair exhibited a reasonable relationship with the administered dose. Notably, hair displayed the highest detection probability (14 out of 17) for compounds, including anabolic agents, hormones, and diuretics, with beta-2 agonists undetected. Diuretics such as furosemide, canrenone, and hydrochlorothiazide showed the highest hair incorporation. Authentic human hair confirmed diuretic detectability, and their use duration was determined via segmental analysis. Noteworthy is the first-time reporting of canrenone in human hair. Anabolic agents were expected in hair, whereas undetectable compounds, such as peptide hormones and beta-2 agonists, were likely due to large molecular mass or high polarity. This study enhances understanding of hair analysis in doping investigations, providing insights into substance detectability.


Assuntos
Anabolizantes , Dopagem Esportivo , Animais , Humanos , Canrenona/análise , Dopagem Esportivo/métodos , Diuréticos/análise , Fezes/química , Cabelo/química , Detecção do Abuso de Substâncias/métodos
2.
Drug Test Anal ; 16(1): 38-48, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37161689

RESUMO

Dietary supplements (DS) are intended for healthy people to maintain or improve their overall health. Its consumption is widespread in large part of the general population and at all levels of athletes. Nevertheless, DS use can also pose health risks to individuals and, in the case of athletes, may lead to adverse analytical findings (AAFs) due to the possibility of DS contamination or adulteration with doping agents banned by the World Anti-Doping Agency. Although educational initiatives are being performed in Brazil to warn the sports community about inadvertent doping cases, AAFs connected to the DS administration have been increasingly growing. The findings of DS analyzed by the Brazilian Doping Control Laboratory (LBCD), between 2017 and 2022, after Testing Authorities (TAs) analysis requests, showed an alarming number of tainted samples. Diuretics were the most common adulterants found in all supplement types. However, the profile of prohibited substances in manufactured and compounded dietary supplements (MDS and CDS, respectively) were distinct, with stimulants being most prevalent in MDS and anabolic agents in CDS products. Additionally, MDS samples generally presented higher estimated concentrations of banned substances (mg/g) than CDS samples (µg/g). The common practice of DS intake by athletes continues to be of great concern for a doping-free sport, given the high prevalence of prohibited substances detected in the analyzed samples by the LBCD. The current Brazilian scenario reinforces the importance of raising awareness in the sports community of the possible consequences of an unintentional doping case linked to DS use.


Assuntos
Dopagem Esportivo , Esportes , Humanos , Brasil , Diuréticos/análise , Atletas , Suplementos Nutricionais/análise
3.
Chem Biodivers ; 19(10): e202200022, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35997661

RESUMO

This study evaluated the diuretic and antiurolithic effect of methanolic extract (MEGHL), dichloromethane (DCM), and ethyl acetate (EtA) fractions obtained from the leaves of Garcinia humilis, a medicinal plant known as achachairu and native to South American countries such as Bolivia, Peru, and Brazil. For the analysis of diuretic effect, the female rats received the treatment with MEGHL (3, 10, and 30 mg/kg), DCM (1, 3 and 10 mg/kg), EtA (1, 3, and 10 mg/kg), hydrochlorothiazide (HCTZ; 10 mg/kg), or vehicle (VEH) after an overload of saline solution. At the end 8 h of the experiment, the urinary parameters were measured. Additionally, the antiurolithic effect was analyzed, in which sodium oxalate was added in synthetic urine in the presence or absence of MEGHL, DCM, and EtA in different concentrations (0.1, 0.3, and 1 mg/mL). MEGHL, DCM, and EtA were able to promote 8-h diuresis in rats. MEGHL treatment at dose 30 mg/kg was accompanied by increased urinary Na+ , K+ and Cl- excretion. Moreover, the DCM and EtA fractions treatment increased K+ and Cl- excretion in the urine, although it does not cause any change in Na+ elimination. All the preparations were able to exert an antiurolithic effect in vitro, decreasing the number of calcium oxalate crystals of the monohydrate and dihydrate types. Taking together, the results presented herein showed that the preparations of G. humilis leaves are promising strategies to induce diuresis and antiurolithic effects.


Assuntos
Garcinia , Plantas Medicinais , Ratos , Animais , Diuréticos/farmacologia , Diuréticos/análise , Oxalato de Cálcio/análise , Cloreto de Metileno/análise , Solução Salina , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/análise , Ratos Wistar , Folhas de Planta/química , Hidroclorotiazida/análise , Hidroclorotiazida/farmacologia , Brasil
4.
Drug Test Anal ; 13(8): 1561-1568, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33982423

RESUMO

Athletics is a highly diverse sport that contains a set of disciplines grouped into jumps, throws, races of varying distances, and combined events. From a physiological standpoint, the physical capabilities linked to success are quite different among disciplines, with varying involvements of muscle strength, muscle power, and endurance. Thus, the use of banned substances in athletics might be dictated by physical dimensions of each discipline. Thus, the aim of this investigation was to analyse the number and distribution of adverse analytical findings per drug class in athletic disciplines. The data included in this investigation were gathered from the Anti-Doping Testing Figure Report made available by the World Anti-Doping Agency (from 2016 to 2018). Interestingly, there were no differences in the frequency of adverse findings (overall,~0.95%, range from 0.77 to 1.70%) among disciplines despite long distance runners having the highest number of samples analysed per year (~9812 samples/year). Sprinters and throwers presented abnormally high proportions of adverse analytical findings within the group of anabolic agents (p < 0.01); middle- and long-distance runners presented atypically high proportions of findings related to peptide hormones and growth factors (p < 0.01); racewalkers presented atypically high proportions of banned diuretics and masking agents (p = 0.05). These results suggest that the proportion of athletes that are using banned substances is similar among the different disciplines of athletics. However, there are substantial differences in the class of drugs more commonly used in each discipline. This information can be used to effectively enhance anti-doping testing protocols in athletics.


Assuntos
Técnicas de Química Analítica/estatística & dados numéricos , Dopagem Esportivo/estatística & dados numéricos , Laboratórios/estatística & dados numéricos , Esportes , Anabolizantes/análise , Atletas , Diuréticos/análise , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/análise , Hormônios Peptídicos/análise , Corrida , Detecção do Abuso de Substâncias/normas
5.
Drug Test Anal ; 13(1): 8-35, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33185038

RESUMO

Analytical chemistry-based research in sports drug testing has been a dynamic endeavor for several decades, with technology-driven innovations continuously contributing to significant improvements in various regards including analytical sensitivity, comprehensiveness of target analytes, differentiation of natural/endogenous substances from structurally identical but synthetically derived compounds, assessment of alternative matrices for doping control purposes, and so forth. The resulting breadth of tools being investigated and developed by anti-doping researchers has allowed to substantially improve anti-doping programs and data interpretation in general. Additionally, these outcomes have been an extremely valuable pledge for routine doping controls during the unprecedented global health crisis that severely affected established sports drug testing strategies. In this edition of the annual banned-substance review, literature on recent developments in anti-doping published between October 2019 and September 2020 is summarized and discussed, particularly focusing on human doping controls and potential applications of new testing strategies to substances and methods of doping specified the World Anti-Doping Agency's 2020 Prohibited List.


Assuntos
Drogas Ilícitas , Substâncias para Melhoria do Desempenho , Detecção do Abuso de Substâncias , Anabolizantes/análise , Diuréticos/análise , Dopagem Esportivo , Hormônios/análise , Humanos , Drogas Ilícitas/análise , Peptídeos e Proteínas de Sinalização Intercelular/análise , Substâncias para Melhoria do Desempenho/análise , Detecção do Abuso de Substâncias/métodos
6.
J Forensic Sci ; 66(1): 272-277, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33027535

RESUMO

Testing for drugs in hair raises several difficulties. Among them is the interpretation of the final concentration(s). In a post-mortem case, analyses revealed the presence of furosemide (12 ng/mL) in femoral blood, although it was not part of the victim's treatment. The prosecutor requested our laboratory to undertake an additional analysis in hair to obtain information about the use of furosemide. A specific method was therefore developed and validated to identify and quantify furosemide in hair by UHPLC-MS/MS. After decontamination of 30 mg of hair, incubation in acidic condition, extraction with ethyl acetate, the samples were analyzed by UHPLC-MS/MS. Furosemide was found in the victim's hair at 225 pg/mg. However, it was not possible to interpret this concentration due to the absence of data in the literature. Therefore, the authors performed a controlled study in two parts. In order to establish the basis of interpretation, several volunteers were tested (four after a single 20 mg administration and twenty-four under daily treatment). The first part indicated that a single dose is not detectable in hair using our method. The second part demonstrated concentrations ranging from 5 to 1110 pg/mg with no correlation between dosage and hair concentrations. The decedent's hair result was interpreted as repeated exposures. In the case of furosemide analysis, hair can provide information about its presence but cannot give information about dosage or frequency of use.


Assuntos
Diuréticos/análise , Furosemida/análise , Cabelo/química , Idoso , Idoso de 80 Anos ou mais , Cromatografia Líquida de Alta Pressão , Feminino , Toxicologia Forense/métodos , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade
7.
Anal Bioanal Chem ; 412(26): 7123-7130, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32737552

RESUMO

This work exploits the applicability of a chemically reduced graphene oxide (CRGO) modification on the electrochemical response of a glassy carbon electrode (GCE) for the first-time sensitive determination of furosemide in natural waters. The batch injection analysis (BIA) is proposed as an analytical method, where CRGO-GCE is coupled to a BIA cell for amperometric measurements. Acetate buffer (0.1 µmol L-1, pH 5.2) was used as the background electrolyte. The modification provided an increase in sensitivity (0.024 µA/µmol L-1), low limit of detection (0.7 µmol L-1), RSD (< 4%), and broad linear range (1-600 µmol L-1). Recovery tests performed in two different concentration ranges resulted in values between 89 and 99%. Recovery tests were performed and compared with high-performance liquid chromatography (HPLC) with UV-Vis detection using Student's t test at a 95% significance level, and no significant differences were found, confirming the accuracy of the method. The developed method is proven faster (169 h-1) compared with the HPLC analysis (5 h-1), also comparable with other flow procedures hereby described, offering a low-cost strategy suitable to quantify an emerging pharmaceutical pollutant. Graphical abstract.


Assuntos
Carbono/química , Diuréticos/análise , Técnicas Eletroquímicas/métodos , Eletrodos , Furosemida/análise , Grafite/química , Poluentes Químicos da Água/análise , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Oxirredução , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta/métodos
8.
Am J Trop Med Hyg ; 103(2): 894-908, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32394884

RESUMO

Falsified and substandard medicines may undermine the progress toward the Sustainable Development Goals. The present study investigated the quality of 13 essential medicines in Cameroon and the Democratic Republic of Congo (DR Congo). Five hundred six medicine samples were collected from the government and faith-based health facilities, private pharmacies, and informal vendors (total 60 facilities). Collected samples were analyzed according to the U.S. Pharmacopeia (USP) for identity, content, and dissolution of their active pharmaceutical ingredients (APIs) and for uniformity of dosage units. Three samples (0.6%) were identified as falsified. Overall, 8.5% of the samples failed USP specifications for the content of the API and 11.7% failed dissolution testing. Medicines from informal vendors showed a higher out-of-specification rate (28.2%) than other types of drug outlets (12.3%; P < 0.0001). All three falsified medicines had been sold by informal vendors. The failure rate of medicines stated to be produced in Europe (5.1%) was lower than that for medicines from Asia (17.7%; P = 0.0049) and Africa (22.2%; P = 0.0042). Medicines against noncommunicable diseases showed a higher failure rate than antibiotics (25.3% versus 12.1%; P = 0.0004). Four hundred fifty-one of the samples were analyzed in Cameroon and the DR Congo with the Global Pharma Health Fund Minilab (thin-layer chromatography and disintegration testing). The three falsified medicines were readily detected in Minilab analysis. However, substandard samples were detected with low sensitivity. A well-enforced ban of medicine sales by informal vendors and increased attention to supplier qualification in the procurement process may reduce the prevalence of substandard and falsified medicines.


Assuntos
Medicamentos Falsificados , Medicamentos Essenciais/normas , Medicamentos Fora do Padrão , Antagonistas de Receptores Adrenérgicos beta 1/análise , Antagonistas de Receptores Adrenérgicos beta 1/normas , Agonistas de Receptores Adrenérgicos beta 2/análise , Agonistas de Receptores Adrenérgicos beta 2/normas , Antibacterianos/análise , Antibacterianos/normas , Anti-Hipertensivos/análise , Anti-Hipertensivos/normas , Camarões , Cromatografia Líquida de Alta Pressão , República Democrática do Congo , Diuréticos/análise , Diuréticos/normas , Medicamentos Essenciais/análise , Humanos , Hipoglicemiantes/análise , Hipoglicemiantes/normas
9.
J Pharm Biomed Anal ; 186: 113332, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32387749

RESUMO

The kinetics and photodegradation mechanism of the pharmaceutical mixture of hydrochlorothiazide (HCT) and amiloride (AML) has been studied in depth using a chemometric approach. Water solutions of HCT and AML, separately or in binary mixtures, were irradiated with forced light at different pH values (3, 7, 9 and 12). Multivariate Curve Resolution - Alternating Least Squares (MCR-ALS) modelling has been applied to the experimental data recorded by UV spectrophotometry and HPLC-UV/MS. 78 data sets were collected and their chemometric processing has allowed the simultaneous determination of the behaviour of the two drugs in the mixture when exposed to light and the dependence of their photodegradation kinetics on pH. MCR-ALS has been applied using three different implementations. Soft-MCR-ALS and hybrid Hard/Soft-MCR-ALS have been used to resolve the experimental data and to get the equilibrium and kinetic parameters of the investigated chemical processes. A third implementation of the MCR-ALS method has been used in the analysis of the incomplete data sets obtained when UV spectrophotometric and HPLC-UV/MS data were simultaneously analysed, using a row- and column-wise incomplete augmented data matrix arrangement. In these matrices, information from HPLC-UV detector was used as a bridge between the data recorded by UV spectrophotometry (acid-base and kinetic reactions monitoring) and the data obtained by HPLC-MS.


Assuntos
Amilorida/química , Diuréticos/química , Hidroclorotiazida/química , Fotólise , Amilorida/análise , Cromatografia Líquida de Alta Pressão , Diuréticos/análise , Combinação de Medicamentos , Hidroclorotiazida/análise , Concentração de Íons de Hidrogênio , Cinética , Análise dos Mínimos Quadrados , Espectrometria de Massas , Espectrofotometria Ultravioleta
10.
Drug Test Anal ; 12(3): 316-322, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31943812

RESUMO

Hair testing is a complementary approach to document doping agent(s) use All prohibited substances but hormones should be detectable in hair Interest and limitations of hair testing for doping agents are reviewed based on the authors' experience Although a lot of data are available for drugs of abuse, controlled studies are missing for anabolic steroids, diuretics and some unusual classes of substances.


Assuntos
Anabolizantes/análise , Diuréticos/análise , Dopagem Esportivo/métodos , Cabelo/química , Detecção do Abuso de Substâncias/métodos , Humanos
11.
J Chromatogr Sci ; 57(6): 528-540, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31209501

RESUMO

The consumption of dietary supplements is increasing every year all over the world and has been accompanied by an increased frequency of adulteration of these products with synthetic pharmaceuticals. Analytical methods that allow testing for the presence of synthetic drugs in dietary supplements are needed to detect such fraudulent practices. To investigate the adulteration of dietary supplements marketed for weight loss using different commercial appeals, we developed an analytical method using ultra-high-performance liquid chromatography-electrospray tandem mass spectrometry (UHPLC-ESI-MS/MS) for simultaneous determination of 32 drugs, including anorexics, anxiolytics, antidepressants, diuretics, laxatives and stimulants. Separation was accomplished in 19 minutes using a Zorbax SB-C18 column and a gradient elution program with 0.05% formic acid in water/acetonitrile as a mobile phase. Limits of quantification ranged from 0.14 to 3.92 µg L-1, and accuracy ranged from 80.00 to 119.48%. A simple extraction procedure was used in the pretreatment step by dissolving the samples in 100% methanol followed by a 1000 to 10,000-fold dilution in the mobile phase and filtration through a Teflon membrane (0.2 µm). The method was applied to the screening and quantification of the drugs in 108 formulations marketed as food supplements for slimming, weight loss, thermogenics, and supplements for meal replacement. Caffeine and p-synephrine were found as stimulants in 80 samples, listed or not on the label.


Assuntos
Fármacos Antiobesidade/análise , Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais/análise , Espectrometria de Massas em Tandem/métodos , Ansiolíticos/análise , Antidepressivos/análise , Estimulantes do Sistema Nervoso Central/análise , Diuréticos/análise , Laxantes/análise , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
12.
J Food Drug Anal ; 27(1): 164-174, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30648569

RESUMO

There is an increasing amount of dietary supplements that are adulterated with diuretics and anti-diabetic drugs; this has become a global problem due to the wide distribution of dietary supplements and the serious negative health effects of the adulterants. In this study, a rapid screening method was developed for detection and confirmation of 35 sulfonamides in supplements by ultra-high performance liquid chromatography quadrupole/time of flight mass spectrometry. For effective extraction of sulfonamides from dietary supplements, four extraction protocols including HLB and WAX solid-phase extraction, Quick Easy Cheap Effective Rugged and Safe method, and pH-controlled liquid-liquid extraction were evaluated, and pH-controlled liquid-liquid extraction method was shown to be the most effective with high recovery efficiency and low matrix effect. Rapid separation of 35 sulfonamides was achieved with the UHPLC C18 column (150 × 2.1 mm, 1.7 um) within 7 min using ammonium acetate aqueous solution (pH 8) and acetonitrile as the mobile phase. From the MS/MS spectra of sulfonamides, common ions (m/z 77.9650 [SO2N]- and m/z 79.9812 [SO2NH2]-) and neutral molecule loss fragments (HCl and SO2) were observed according to their structural characteristics. Extracted common ion chromatograms and neutral loss scan of these characteristic fragments could effectively apply for rapid screening of sulfonamides in various types of supplements. A reduced mass tolerance window of ±5 ppm was useful for detecting targeted and untargeted sulfonamides and could avoid false positive and false negative results. Overall calibration curves within dynamic range for all targets were shown to be linear with a correlation coefficient R2 > 0.995 and limits of detection ranged from 0.04 to 11.18 ng/g for all sulfonamides. The established method was successfully applied for screening and confirmation of sulfonamides in various supplements. The developed method will be helpful for the identification of sulfonamide diuretics and anti-diabetics in dietary supplements, promoting public health and consumer safety.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais/análise , Espectrometria de Massas/métodos , Sulfonamidas/análise , Diuréticos/análise , Contaminação de Medicamentos , Hipoglicemiantes/análise , Extração em Fase Sólida , Sulfonamidas/isolamento & purificação
13.
Drug Test Anal ; 11(1): 157-161, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29920984

RESUMO

An athlete contested an adverse analytical finding involving hydrochlorothiazide, and requested our laboratory for testing his hair. As there is no reference in the literature about identification of hydrochlorothiazide in hair, several volunteers were first enrolled (4 after a single 25 mg administration and 10 with daily therapeutic treatment). A specific method was developed by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS. Hair samples were decontaminated with dichloromethane and 30 mg were incubated in buffer at pH 7.0 for 15 hours at 50°C. Then, 5 mL ethyl acetate was added for extraction. Linearity was observed for hydrochlorothiazide concentrations ranging from 5 to 2000 pg/mg. The limit of quantification was 5 pg/mg. The coefficients of variation (CVs) of repeatability and matrix effect were lower than 20%. Analysis of the 0-2-cm segment of the 4 volunteers having received a single dose, collected 1 month after administration, was negative at the limit of quantification. The hair of the 10 patients (proximal 2 cm) on daily treatment was positive with concentrations ranging from 12 to 1845 pg/mg, with no correlation between daily dose and concentration. The athlete's hair tested positive for hydrochlorothiazide at 36 pg/mg in the segment corresponding to the period of the urinary control. Since a single exposure to hydrochlorothiazide is not detectable in hair and based on the results of the patients on daily treatment, the concentration found in the athlete has been interpreted as corresponding to repeated exposures, where it was not possible to establish the dosage and the frequency.


Assuntos
Diuréticos/análise , Dopagem Esportivo/prevenção & controle , Cabelo/química , Hidroclorotiazida/análise , Detecção do Abuso de Substâncias/métodos , Adolescente , Adulto , Idoso , Diuréticos/administração & dosagem , Diuréticos/metabolismo , Relação Dose-Resposta a Droga , Cabelo/efeitos dos fármacos , Cabelo/metabolismo , Humanos , Hidroclorotiazida/administração & dosagem , Hidroclorotiazida/metabolismo , Masculino , Pessoa de Meia-Idade , Detecção do Abuso de Substâncias/normas , Adulto Jovem
14.
Drug Test Anal ; 11(3): 512-522, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30194914

RESUMO

Diuretic agents are prohibited in sports in- and out-of-competition according to the regulations of the World Anti-Doping Agency (WADA) because of their possible masking effects on other doping agents in urine samples, and their ability to produce fast acute weight losses. Despite previous studies reported adverse analytical findings (AAFs) resulting from contaminations at ppm level (µg/g) of medicinal products, and recommended to introduce reporting limits for diuretics in doping controls, these are not adopted in analyses performed by WADA-accredited laboratories. We report the case of an athlete with two AAFs for hydrochlorothiazide (HCTZ) at low urinary concentrations (<10 ng/mL), who declared the use of nutritional supplements prepared in a compounding pharmacy. His nutritional supplements were analyzed revealing HCTZ presence in different concentrations, at the ppm level (µg/g and ng/mL). With the aim of testing the plausibility of the observed urinary HCTZ concentrations with the nutritional supplement ingestion, a urinary excretion study with three healthy volunteers was performed. HCTZ-contaminated powder (6.4 µg/g of HCTZ) was administered to each subject in different dosages, reproducing the possible ingestion pattern occurred. Urine specimens were collected before and after ingestion of the powder, up to 24 hours, and underwent liquid-liquid extraction and liquid chromatography-tandem mass spectrometry determination. Post-administration specimens were found to contain HCTZ at concentrations of 5-230 ng/mL, which supported the accidental inadvertent intake of the prohibited substance by the athlete. This study makes the argument that the introduction of reporting limits for diuretics are warranted in doping control samples, in order to protect against inadvertent AAFs due to contaminated products.


Assuntos
Suplementos Nutricionais/análise , Contaminação de Medicamentos , Hidroclorotiazida/urina , Detecção do Abuso de Substâncias/métodos , Adulto , Cromatografia Líquida , Diuréticos/análise , Diuréticos/urina , Dopagem Esportivo/legislação & jurisprudência , Voluntários Saudáveis , Humanos , Hidroclorotiazida/análise , Legislação de Medicamentos/normas , Extração Líquido-Líquido , Masculino , Pós/química , Espectrometria de Massas em Tandem
15.
J Ethnopharmacol ; 225: 53-63, 2018 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-29933015

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Luehea divaricata Mart. (Malvaceae) is an important medicinal species that is widely used as a diuretic in the Brazilian Pantanal region. An ethanolic supernatant that was obtained from an infusion of leaves of this species (ESLD) was recently shown to exert hypotensive and diuretic activity. Nevertheless, the secondary metabolites that are responsible for this activity and the molecular mechanisms of pharmacological action remain unknown. AIM: We performed a detailed study to identify possible active metabolites that are present in different ESLD fractions and investigated their effects on renal and peripheral arteriolar tone. We further evaluated their interrelations with sustained diuretic and hypotensive actions. MATERIALS AND METHODS: The ESLD was first obtained from L. divaricata leaves, and liquid-liquid fractionation was performed. The fractions were analyzed by liquid chromatography-mass spectrometry. An ethyl acetate fraction (AceFr), n-butanolic fraction (ButFr), and aqueous fraction (AqueFr) were then orally administered in male Wistar rats in a single dose or daily for 7 days. The doses were previously defined based on the yield that was obtained from each fraction. Hydrochlorothiazide was used as a positive control. Blood pressure, heart rate, urinary volume, pH, density, and urinary sodium, potassium, chloride, and calcium levels were measured. Serum levels of nitrite, thiobarbituric acid reactive species, nitrotyrosine, aldosterone, vasopressin, and plasma angiotensin converting enzyme activity were also measured. Finally, the direct effects of the ButFr on renal and mesenteric arteriolar tone and the role of nitric oxide and prostaglandins in the renal and hemodynamic effects were investigated. RESULTS: Of the fractions that were tested, only the ButFr exerted significant diuretic and saluretic effects. The AceFr and ButFr also had acute hypotensive effects, but only the ButFr maintained its response after 7 days of treatment. Prolonged treatment with the ButFr increased serum nitrite levels and significantly reduced oxidative and nitrosative markers of stress. Additionally, the ButFr caused a vasodilatory response in the renal and mesenteric arteriolar beds through the release of nitric oxide and prostaglandins. Finally, the diuretic and hypotensive effects of the ButFr were completely blocked by pretreatment with Nω-nitro-L-arginine methyl ester and indomethacin, thus demonstrating the direct involvement of nitric oxide and prostaglandins in these effects. CONCLUSION: The ButFr that was obtained from Luehea divaricata exerted sustained diuretic and hypotensive effects. These effects were apparently attributable to the release of nitric oxide and prostaglandins, which reduce renal and peripheral arteriolar tone and lead to an increase in the glomerular filtration rate and a reduction of global peripheral resistance. These findings suggest that the ButFr may be a potential complementary therapy for several conditions in which diuretic and hypotensive effects are required.


Assuntos
Anti-Hipertensivos/farmacologia , Diuréticos/farmacologia , Malvaceae , Extratos Vegetais/farmacologia , Animais , Anti-Hipertensivos/análise , Arteríolas/efeitos dos fármacos , Arteríolas/fisiologia , Pressão Sanguínea/efeitos dos fármacos , Diuréticos/análise , Rim/irrigação sanguínea , Rim/efeitos dos fármacos , Rim/fisiologia , Masculino , Mesentério/efeitos dos fármacos , Mesentério/fisiologia , Óxido Nítrico/fisiologia , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/análise , Folhas de Planta , Prostaglandinas/fisiologia , Ratos Wistar , Artéria Renal/efeitos dos fármacos , Artéria Renal/fisiologia
16.
Biomed Chromatogr ; 31(8)2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28146607

RESUMO

Hydrochlorothiazide (HCT) is a diuretic used to treat hypertension. In order to study its intestinal permeation behavior applying an ex vivo methodology, a rapid, sensitive and selective reversed-phase liquid chromatography (RP-HPLC) method coupled with UV detection (RP-HPLC UV) was developed for the analysis of HCT in TC199 culture medium used as mucosal and serosal solutions in the everted rat intestinal sac model. Also, analytical procedures for the quantification of HCT by RP-HPLC with UV detection required a sample preparation step by solid-phase extraction. The method was validated in the concentration range of 8.05 × 10-7 to 3.22 × 10-5 m for HCT. Chromatographic parameters, namely carry-over, lower limit of quantification (1.4491 × 10-7 m), limit of detection (3.8325 × 10-8 m), selectivity, inter- and intraday precision and extraction recovery, were determined and found to be adequate for the intended purposes. The validated method was successfully used for permeability assays across rat intestinal epithelium applying the ex vivo everted rat gut sac methodology to study the permeation behavior of HCT.


Assuntos
Anti-Hipertensivos/farmacocinética , Cromatografia de Fase Reversa/métodos , Diuréticos/farmacocinética , Hidroclorotiazida/farmacocinética , Extração em Fase Sólida/métodos , Animais , Anti-Hipertensivos/análise , Diuréticos/análise , Hidroclorotiazida/análise , Absorção Intestinal , Limite de Detecção , Permeabilidade , Ratos
17.
Drug Test Anal ; 9(1): 6-29, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27885819

RESUMO

There has been an immense amount of visibility of doping issues on the international stage over the past 12 months with the complexity of doping controls reiterated on various occasions. Hence, analytical test methods continuously being updated, expanded, and improved to provide specific, sensitive, and comprehensive test results in line with the World Anti-Doping Agency's (WADA) 2016 Prohibited List represent one of several critical cornerstones of doping controls. This enterprise necessitates expediting the (combined) exploitation of newly generated information on novel and/or superior target analytes for sports drug testing assays, drug elimination profiles, alternative test matrices, and recent advances in instrumental developments. This paper is a continuation of the series of annual banned-substance reviews appraising the literature published between October 2015 and September 2016 concerning human sports drug testing in the context of WADA's 2016 Prohibited List. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Técnicas de Química Analítica/métodos , Dopagem Esportivo , Detecção do Abuso de Substâncias/métodos , Anabolizantes/análise , Estimulantes do Sistema Nervoso Central/análise , Técnicas de Química Analítica/instrumentação , Diuréticos/análise , Dopagem Esportivo/métodos , Glucocorticoides/análise , Testes Hematológicos/instrumentação , Testes Hematológicos/métodos , Humanos , Entorpecentes/análise , Detecção do Abuso de Substâncias/instrumentação , Urinálise/instrumentação , Urinálise/métodos
18.
BMC Complement Altern Med ; 16(1): 516, 2016 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-27964714

RESUMO

BACKGROUND: Vepris heterophylla (Rutaceae) is a medicinal plant used empirically in African traditional medicine for many clinical conditions including edematous disorders and hypertension. V. heterophylla aqueous extract has been used in northern part of Cameroon by traditional healers for the treatment of arterial hypertension. The study aim was to assess the putative diuretic and antioxidant properties of V. heterophylla leaves aqueous extract. METHODS: Adult rats were administered with V. heterophylla leaves aqueous extract acutely (24 h) at doses 50, 100, 150, 200 and 250 mg/kg (per os). The two positive control groups received the diuretic drugs furosemide (5 mg/kg) and hydrochlorothiazide (HCTZ, 10 mg/kg), while negative control group received only an equivalent volume of distilled water. Urinary elimination of electrolytes in response to treatments was evaluated, together with changes in concentrations of creatinine, urea, aldosterone, glucose and albumin in urine and plasma. Various urinary indicators of kidney function and plasmatic markers of oxidative stress were also assessed. RESULTS: The findings indicated that the aqueous extract of V. heterophylla at doses ranging from 150 to 250 mg/kg caused a significant and dose-dependent increase of urinary water and electrolytes excretion in normal rats. The aqueous extract of the leaves of V. heterophylla accelerated the elimination of overloaded fluid. At the maximum of diuretic response, urinary osmolarity decreased significantly when compared with controls. Oral administration of aqueous extract at different doses produced a significant diuresis and slight increase in electrolytes (Na+, K+ and Cl-) excretion. The results obtained were compared with standard drug-furosemide (5 mg/kg) and hydrochlorothiazide (10 mg/kg). These effects were observed predominantly at 250 mg/kg dose. CONCLUSIONS: Our findings strongly suggest that V. heterophylla aqueous extract has diuretic and antioxidant activities, and deserves further studies considering the potential for the treatment of hypertension.


Assuntos
Antioxidantes/análise , Diuréticos/análise , Rutaceae/química , Animais , Biomarcadores/sangue , Feminino , Testes de Função Renal , Masculino , Estresse Oxidativo , Extratos Vegetais/química , Folhas de Planta/química , Ratos Wistar
19.
Forensic Sci Int ; 267: 166-172, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27611956

RESUMO

Hydrochlorothiazide (HCTZ, 6-chloro-3,4-dihydro-2H-1,2,4-benzothiadiazine-7-sulfonamide-1,1-dioxide) belongs to the class of diuretic agents that represent one of today's cornerstones of the treatment of hypertensive patients. In addition to its clinical relevance, HCTZ is prohibited in sports according to the regulations of the World Anti-Doping Agency (WADA) at all times and has frequently been detected in sports drug testing urine samples worldwide since its ban was introduced in 1988. Despite these facts, the adverse analytical finding concerning HCTZ in an in-competition routine doping control sample collected in December 2014 was further investigated, particularly motivated by the comparably low urinary concentration of the drug accounting for approximately 5ng/mL. The athlete in question did not declare the use of any nutritional supplement or medication other than the ingestion of a non-steroidal anti-inflammatory drug (NSAID) prior to competition. Hence, the drug (formulated as coated tablet) provided by the athlete as well as the corresponding retention sample of the manufacturer were analyzed. Noteworthy, both samples confirmed the presence of about 2µg of HCTZ per tablet. In order to further probe for the plausibility of the observed urinary HCTZ concentrations with the scenario of drug ingestion and subsequent doping control sample collection, administration studies with produced HCTZ-spiked placebo-tablets (2.5µg of HCTZ/tablet) were conducted. Urine specimens were collected prior to and after ingestion of the drug and subjected to routine doping control analytical procedures employing liquid chromatography/tandem mass spectrometry. While blank urine samples returned negative test results, post-administration specimens were found to contain HCTZ at concentrations of approximately 1-16ng/mL, which supported the athlete's inadvertent intake of HCTZ via contaminated NSAID tablets. Due to the substantial sensitivity of test methods employed today by doping control laboratories, even drug contaminations ranging within the good manufacturing practice (GMP) limit of 10ppm overall carry-over can evidently lead to adverse analytical findings. This calls into question whether selected (classes of) substances such as diuretics should be reported only when exceeding a defined reporting level and/or whether adverse analytical findings of non-threshold substances should be reported with an estimated semi-quantitative concentration of the identified substance to facilitate the result management by anti-doping organizations.


Assuntos
Anti-Inflamatórios não Esteroides/química , Diuréticos/análise , Dopagem Esportivo , Contaminação de Medicamentos , Hidroclorotiazida/análise , Anti-Inflamatórios não Esteroides/urina , Cromatografia Líquida , Humanos , Masculino , Comprimidos , Espectrometria de Massas em Tandem , Adulto Jovem
20.
Drug Test Anal ; 8(1): 7-29, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26767774

RESUMO

The aim of improving anti-doping efforts is predicated on several different pillars, including, amongst others, optimized analytical methods. These commonly result from exploiting most recent developments in analytical instrumentation as well as research data on elite athletes' physiology in general, and pharmacology, metabolism, elimination, and downstream effects of prohibited substances and methods of doping, in particular. The need for frequent and adequate adaptations of sports drug testing procedures has been incessant, largely due to the uninterrupted emergence of new chemical entities but also due to the apparent use of established or even obsolete drugs for reasons other than therapeutic means, such as assumed beneficial effects on endurance, strength, and regeneration capacities. Continuing the series of annual banned-substance reviews, literature concerning human sports drug testing published between October 2014 and September 2015 is summarized and reviewed in reference to the content of the 2015 Prohibited List as issued by the World Anti-Doping Agency (WADA), with particular emphasis on analytical approaches and their contribution to enhanced doping controls.


Assuntos
Detecção do Abuso de Substâncias/métodos , Agonistas Adrenérgicos beta/análise , Antagonistas Adrenérgicos beta/análise , Anabolizantes/análise , Canabinoides/análise , Diuréticos/análise , Dopagem Esportivo/métodos , Dosagem de Genes , Glucocorticoides/análise , Hormônios/análise , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/análise , Espectrometria de Massas/métodos , Substâncias para Melhoria do Desempenho/análise
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