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1.
Mol Biol Rep ; 49(7): 6931-6943, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35301654

RESUMEN

BACKGROUND: Coronavirus disease 2019 (COVID-19) is caused by a novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It is known that host microRNAs (miRNAs) can be modulated to favor viral infection or to protect the host. Herein, we report preliminary results of a study aiming at identifying differentially expressed plasmatic miRNAs in Brazilian patients with COVID-19. METHODS AND RESULTS: miRNAs were extracted from the plasma of eight patients with COVID-19 (four patients with mild COVID-19 and four patients with severe/critical COVID-19) and four healthy controls. Patients and controls were matched for sex and age. miRNA expression levels were detected using high-throughput sequencing. Differential miRNA expression and enrichment analyses were further evaluated. A total of 18 miRNAs were differentially expressed between patients with COVID-19 and controls. miR-4433b-5p, miR-6780b-3p, miR-6883-3p, miR-320b, miR-7111-3p, miR-4755-3p, miR-320c, and miR-6511a-3p were the most important miRNAs significantly involved in the PI3K/AKT, Wnt/ß-catenin, and STAT3 signaling pathways. Moreover, 42 miRNAs were differentially expressed between severe/critical and mild patients with COVID-19. miR-451a, miR-101-3p, miR-185-5p, miR-30d-5p, miR-25-3p, miR-342-3p, miR-30e-5p, miR-150-5p, miR-15b-5p, and miR-29c-3p were the most important miRNAs significantly involved in the Wnt/ß-catenin, NF-κß, and STAT3 signaling pathways. CONCLUSIONS: If validated by quantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR) in a larger number of participants, the miRNAs identified in this study might be used as possible biomarkers for the diagnosis and severity of COVID-19.


Asunto(s)
COVID-19 , MicroARNs , Brasil/epidemiología , COVID-19/genética , Perfilación de la Expresión Génica/métodos , Humanos , MicroARNs/metabolismo , Fosfatidilinositol 3-Quinasas/genética , SARS-CoV-2 , beta Catenina/genética
2.
Nat Prod Res ; 36(12): 3117-3123, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34142601

RESUMEN

Bearing in mind the several medicinal properties of Mentha genus, this work aimed to evaluate the anti-proliferative potential of the ethanolic extract (EE) and fractions from M. aquatica L aerial parts. Using the anti-proliferative protocol developed by the NCI/USA, four fractions (F2 - F4 and F6) obtained from EE showed promising anti-proliferative profile against a panel of human tumor and non-tumor cell lines. After 24-h exposure, F2 (0.25 µg/mL) showed potent and irreversible anti-proliferative effect without inducing cell cycle arrest in both NCI-H460 and MCF-7 cells, without (anti) estrogenic activity. These effects were lost after storage of F2 diluted in dimethyl sulfoxide at -80 °C during 2 weeks. Analysis by gas chromatography coupled to mass detection evidenced some chemical changes induced by F2 storage in solution. The present study demonstrated the anti-proliferative effect of M. aquatica. Further studies are necessary to determine better storage conditions to enhance F2 stability.


Asunto(s)
Mentha , Puntos de Control del Ciclo Celular , Proliferación Celular , Humanos , Células MCF-7 , Mentha/química , Componentes Aéreos de las Plantas , Extractos Vegetales/química , Extractos Vegetales/farmacología
3.
Biomed Chromatogr ; 34(12): e4952, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32706449

RESUMEN

The detection of the markers of Cannabis consumption in biological specimens is an important task for drug testing laboratories in varous contexts. A simple assay combining salting-out assisted liquid-liquid extraction sample preparation and LC-MS/MS analysis was applied to the measurement of Δ9 -tetrahydrocannabinol, 11-nor-9-carboxy-Δ9 -tetrahydrocannabinol (THC-COOH), 11-hydroxy-Δ9 -tetrahydrocannabinol, cannabinol and cannabidiol concentrations in 100 µl plasma specimens. The assay had linearity of 1-100 ng ml-1 for THC-COOH and 0.5-50 ng ml-1 for the other tested cannabinoids. Assay validation criteria were fulfilled. Extraction yields (88.7-97.3%) and internal-standard correct matrix effects (-9.6 to +5.4%) were acceptable. The assay was applied to 238 clinical specimens from trauma patients, with 19 samples presenting quantifiable concentrations of at least one of the target compounds. The developed assay is a simple and efficient strategy for simultaneous measurement of Δ9 -tetrahydrocannabinol, THC-COOH, 11-hydroxy-Δ9 -tetrahydrocannabinol, cannabinol and cannabidiol concentrations in plasma specimens.


Asunto(s)
Cannabinoides/sangre , Cromatografía Líquida de Alta Presión/métodos , Extracción Líquido-Líquido/métodos , Espectrometría de Masas en Tándem/métodos , Adulto , Cannabinoides/química , Cannabinoides/aislamiento & purificación , Humanos , Modelos Lineales , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
4.
Alcohol Clin Exp Res ; 43(6): 1066-1076, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30908675

RESUMEN

BACKGROUND: Alcohol abuse is a health concern worldwide. Studies have associated alcohol abuse with cardiovascular impairments. In this study, we investigated differences in the effects of chronic alcohol vapor exposure on cardiovascular function between male and female rats by using the alcohol vapor chamber method to induce alcohol addiction-like behaviors in rats. METHODS: We exposed male and female Long-Evans rats to alcohol vapor for 14 hours, followed by ethanol withdrawal for 10 hours, for 30 consecutive days or room air (control groups). The animals underwent preparation for the surgical implantation of cannulas into femoral vessels, for allowing the assessment of the basal arterial pressure and heart rate values, baroreflex function, and autonomic activity. RESULTS: Female control rats showed higher basal heart rate compared to male control rats. Chronic alcohol vapor inhalation reduced basal heart rate in females, but not in males; this effect was followed by an increase in the parasympathetic tone of the heart. Further, female rats subjected to alcohol vapor showed an increase in the baroreflex activity. CONCLUSIONS: These findings suggest that females are more sensitive to chronic alcohol vapor exposure than males because they had a reduction in basal heart rate and changes in the baroreflex activity.


Asunto(s)
Sistema Nervioso Autónomo/efectos de los fármacos , Depresores del Sistema Nervioso Central/efectos adversos , Etanol/efectos adversos , Hemodinámica/efectos de los fármacos , Administración por Inhalación , Animales , Depresores del Sistema Nervioso Central/administración & dosificación , Etanol/administración & dosificación , Femenino , Masculino , Ratas Long-Evans
5.
J Forensic Sci ; 62(6): 1479-1486, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28205217

RESUMEN

The variations found in the elemental composition in ecstasy samples result in spectral profiles with useful information for data analysis, and cluster analysis of these profiles can help uncover different categories of the drug. We provide a cluster analysis of ecstasy tablets based on their elemental composition. Twenty-five elements were determined by ICP-MS in tablets apprehended by Sao Paulo's State Police, Brazil. We employ the K-means clustering algorithm along with C4.5 decision tree to help us interpret the clustering results. We found a better number of two clusters within the data, which can refer to the approximated number of sources of the drug which supply the cities of seizures. The C4.5 model was capable of differentiating the ecstasy samples from the two clusters with high prediction accuracy using the leave-one-out cross-validation. The model used only Nd, Ni, and Pb concentration values in the classification of the samples.


Asunto(s)
Drogas Ilícitas/química , N-Metil-3,4-metilenodioxianfetamina/química , Algoritmos , Brasil , Análisis por Conglomerados , Árboles de Decisión , Contaminación de Medicamentos , Tráfico de Drogas , Humanos , Espectrometría de Masas/métodos , Comprimidos
6.
Toxicology ; 376: 44-50, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-27129946

RESUMEN

Crack cocaine has a high potential to induce cocaine addiction and its smoke contains cocaine's pyrolysis product anhydroecgonine methyl ester (AEME), a partial agonist at M1- and M3-muscarinic acetylcholine receptor and an antagonist at the remaining subtypes. No reports have assessed AEME's role in addiction. Adult male Wistar rats were intraperitoneally administered with saline, 3mg/kg AEME, 15mg/kg cocaine, or a cocaine-AEME combination on every other day during a period of 9 days. After a 7-days withdrawal period, a challenge injection of the respective drugs was performed on the 17th day. The locomotor activity was evaluated on days 1, 3, 5, 7, 9 and 17, as well as dopamine levels (9th day) and dopaminergic receptors proteins (D1R and D2R on the 17th day) in the caudate-putamen (CPu) and nucleus accumbens (NAc). AEME was not able to induce the expression of behavioral sensitization, but it substantially potentiates cocaine-effects, with cocaine-AEME combination presenting higher expression than cocaine alone. An increase in the dopamine levels in the CPu in all non-saline groups was observed, with the highest levels in the cocaine-AEME group. There was a decrease in D1R protein level in this brain region only for cocaine and cocaine-AEME groups. In the NAc, an increase in the dopamine levels was only observed for cocaine and cocaine-AEME groups, with no changes in both D1R and D2R protein levels. These behavioral and neurochemical data indicate that AEME alone does not elicit behavioral sensitization but it significantly potentiates cocaine effects when co-administered, resulting in dopamine increase in CPu and NAc, brain regions where dopamine release is mediated by cholinergic activity.


Asunto(s)
Cocaína/análogos & derivados , Cocaína/administración & dosificación , Cocaína/metabolismo , Dopamina/metabolismo , Actividad Motora/efectos de los fármacos , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Sinergismo Farmacológico , Masculino , Actividad Motora/fisiología , Ratas , Ratas Wistar , Receptores Dopaminérgicos/metabolismo
7.
Sci Rep ; 5: 17555, 2015 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-26626425

RESUMEN

The smoke of crack cocaine contains cocaine and its pyrolysis product, anhydroecgonine methyl ester (AEME). AEME possesses greater neurotoxic potential than cocaine and an additive effect when they are combined. Since atropine prevented AEME-induced neurotoxicity, it has been suggested that its toxic effects may involve the muscarinic cholinergic receptors (mAChRs). Our aim is to understand the interaction between AEME and mAChRs and how it can lead to neuronal death. Using a rat primary hippocampal cell culture, AEME was shown to cause a concentration-dependent increase on both total [(3)H]inositol phosphate and intracellular calcium, and to induce DNA fragmentation after 24 hours of exposure, in line with the activation of caspase-3 previously shown. Additionally, we assessed AEME activity at rat mAChR subtypes 1-5 heterologously expressed in Chinese Hamster Ovary cells. l-[N-methyl-(3)H]scopolamine competition binding showed a preference of AEME for the M2 subtype; calcium mobilization tests revealed partial agonist effects at M1 and M3 and antagonist activity at the remaining subtypes. The selective M1 and M3 antagonists and the phospholipase C inhibitor, were able to prevent AEME-induced neurotoxicity, suggesting that the toxicity is due to the partial agonist effect at M1 and M3 mAChRs, leading to DNA fragmentation and neuronal death by apoptosis.


Asunto(s)
Cocaína/análogos & derivados , Hipocampo/metabolismo , Síndromes de Neurotoxicidad/metabolismo , Neurotoxinas/toxicidad , Receptor Muscarínico M1/metabolismo , Receptor Muscarínico M3/metabolismo , Animales , Apoptosis/efectos de los fármacos , Células CHO , Cocaína/toxicidad , Cricetinae , Cricetulus , Fragmentación del ADN/efectos de los fármacos , Femenino , Hipocampo/patología , Síndromes de Neurotoxicidad/patología , Ratas , Factores de Tiempo
8.
Bioanalysis ; 7(16): 2041-56, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26327184

RESUMEN

BACKGROUND: DBS are an increasingly common clinical matrix. METHODS & RESULTS: Sensitive and specific methods for DBS and venous blood cocaine and metabolite detection by LC-HRMS and 2D GC-MS, respectively, were validated to examine correlation between concentrations following controlled intravenous cocaine administration. Linear ranges from 1 to 200 µg/l were achieved, with acceptable bias and imprecision. Authentic matched specimens' (392 DBS, 97 venous blood) cocaine and benzoylecgonine concentrations were qualitatively similar, but DBS had much greater variability (21.4-105.9 %CV) and were lower than in blood. CONCLUSION: DBS offer advantages for monitoring cocaine intake; however, differences between capillary and venous blood and DBS concentration variability must be addressed.


Asunto(s)
Cocaína/administración & dosificación , Cocaína/sangre , Pruebas con Sangre Seca/métodos , Adulto , Cromatografía Liquida/métodos , Cocaína/análogos & derivados , Cocaína/metabolismo , Femenino , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Inyecciones Intravenosas , Masculino , Espectrometría de Masas/métodos , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
9.
Drug Test Anal ; 7(10): 877-83, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25786659

RESUMEN

Methamphetamine is included in drug testing programmes due to its high abuse potential. d-Methamphetamine is a scheduled potent central nervous system stimulant, while l-methamphetamine is the unscheduled active ingredient in the over-the-counter nasal decongestant Vicks® VapoInhaler™. No data are available in oral fluid (OF) and few in plasma after controlled Vicks® VapoInhaler™ administration. We quantified methamphetamine and amphetamine enantiomers in OF collected with two different devices and plasma via a fully validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Additionally, OF were analyzed with an on-site screening device. Sixteen participants received 7 Vicks® VapoInhaler™ doses according to manufacturer's recommendations. Specimens were collected before and up to 32 h after the first dose. No d-methamphetamine or d-amphetamine was detected in any sample. All participants had measurable OF l-methamphetamine with median maximum concentrations 14.8 and 16.1 µg/L in Quantisal™ and Oral-Eze® devices, respectively, after a median of 5 doses. One participant had measurable OF l-amphetamine with maximum concentrations 3.7 and 5.5 µg/L after 6 doses with the Quantisal™ and Oral-Eze® devices, respectively. There were no positive DrugTest® 5000 results. In the cutoff range 20-50 µg/L methamphetamine with amphetamine ≥limit of detection, 3.1-10.1% of specimens were positive; first positive results were observed after 1-4 doses. Two participants had detectable plasma l-methamphetamine, with maximum observed concentrations 6.3 and 10.0 µg/L after 2 and 5 doses, respectively. Positive OF and plasma methamphetamine results are possible after Vicks® VapoInhaler™ administration. Chiral confirmatory analyses are necessary to rule out VapoInhaler™ intake. Implementing a selective d-methamphetamine screening assay can help eliminate false-positive OF results.


Asunto(s)
Anfetamina/análisis , Anfetamina/sangre , Estimulantes del Sistema Nervioso Central/análisis , Estimulantes del Sistema Nervioso Central/sangre , Metanfetamina/análisis , Metanfetamina/sangre , Saliva/química , Administración Intranasal , Adulto , Anfetamina/administración & dosificación , Estimulantes del Sistema Nervioso Central/administración & dosificación , Cromatografía Liquida/métodos , Femenino , Humanos , Límite de Detección , Masculino , Metanfetamina/administración & dosificación , Persona de Mediana Edad , Manejo de Especímenes/instrumentación , Estereoisomerismo , Detección de Abuso de Sustancias/instrumentación , Detección de Abuso de Sustancias/métodos , Espectrometría de Masas en Tándem/métodos , Adulto Joven
10.
Drug Test Anal ; 7(7): 586-91, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25345619

RESUMEN

Opiates are an important drug class in drug testing programmes. Ingestion of poppy seeds containing morphine and codeine can yield positive opiate tests and mislead result interpretation in forensic and clinical settings. Multiple publications evaluated urine opiate concentrations following poppy seed ingestion, but only two addressed oral fluid (OF) results; neither provided the ingested morphine and codeine dosage. We administered two 45 g raw poppy seed doses, each containing 15.7 mg morphine and 3.1 mg codeine, 8 h apart to 17 healthy adults. All OF specimens were screened by on-site OF immunoassay Draeger DrugTest 5000, and confirmed with OF collected with Oral-Eze® device and quantified by liquid chromatography-tandem mass spectrometry (1 µg/L morphine and codeine limits of quantification). Specimens (n = 459) were collected before and up to 32 h after the first dose. All specimens screened positive 0.5 h after dosing and remained positive for 0.5-13 h at Draeger 20 µg/L morphine cut-off. Maximum OF morphine and codeine concentrations (Cmax ) were 177 and 32.6 µg/L, with times to Cmax (Tmax ) of 0.5-1 h and 0.5-2.5 h post-dose, respectively. Windows of detection after the second dose extended at least 24 h for morphine and to 18 h for codeine. After both doses, the last morphine positive OF result was 1 h with 40 µg/L 2004 proposed US Substance Abuse and Mental Health Services Administration cut-off, and 0.5 h with 95 µg/L cut-off, recently recommended by the Driving under the Influence of Drugs and Medicines project. Positive OF morphine results are possible 0.5-1 h after ingestion of 15.7 mg of morphine in raw poppy seeds, depending on the cut-off employed.


Asunto(s)
Codeína/análisis , Morfina/análisis , Papaver/química , Saliva/química , Semillas/química , Detección de Abuso de Sustancias/métodos , Administración Oral , Adulto , Codeína/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Morfina/metabolismo , Saliva/metabolismo , Adulto Joven
11.
Bioanalysis ; 4(14): 1731-8, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22877219

RESUMEN

BACKGROUND: Ayahuasca is a psychoactive plant beverage originally used by indigenous people throughout the Amazon Basin, long before its modern use by syncretic religious groups established in Brazil, the USA and European countries. The objective of this study was to develop a method for quantification of dimethyltryptamine and ß-carbolines in human plasma samples. RESULTS: The analytes were extracted by means of C18 cartridges and injected into LC-MS/MS, operated in positive ion mode and multiple reaction monitoring. The LOQs obtained for all analytes were below 0.5 ng/ml. By using the weighted least squares linear regression, the accuracy of the analytical method was improved at the lower end of the calibration curve (from 0.5 to 100 ng/ml; r(2)> 0.98). CONCLUSION: The method proved to be simple, rapid and useful to estimate administered doses for further pharmacological and toxicological investigations of ayahuasca exposure.


Asunto(s)
Banisteriopsis/efectos adversos , Carbolinas/sangre , Alcaloides Indólicos/sangre , N,N-Dimetiltriptamina/sangre , Animales , Banisteriopsis/química , Calibración , Carbolinas/administración & dosificación , Cromatografía Liquida/métodos , Femenino , Humanos , Alcaloides Indólicos/administración & dosificación , Análisis de los Mínimos Cuadrados , Límite de Detección , Masculino , N,N-Dimetiltriptamina/administración & dosificación , Extractos Vegetales/administración & dosificación , Ratas , Estándares de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrometría de Masas en Tándem/métodos
12.
Clin Toxicol (Phila) ; 47(6): 598-601, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19586360

RESUMEN

OBJECTIVE: To report a case of serotonin syndrome (SS) after sibutramine overdose in a child. CASE REPORT: A 4-year-old girl was admitted 25 h after accidentally ingesting approximately 27 pills of sibutramine (15 mg, approximately 23 mg/kg). The child developed clinical features suggestive of SS, including diaphoresis, tachycardia, hypertension, agitation, insomnia, incoordination, hypertonia (lower limbs >> upper limbs), and hallucinations. Serum creatine phosphokinase levels reached a peak on day 3 (2,577 U/L, reference value <145), suggesting mild rhabdomyolysis. No relevant changes were detected in other laboratory examinations or in the electrocardiogram throughout the period of hospitalization. The quantification of sibutramine and the active metabolites, M1 (mono-desmethyl sibutramine) and M2 (di-desmethyl sibutramine), by liquid chromatography/electrospray ionization tandem mass spectrometry in six sequential samples collected from 25 to 147 h post-ingestion revealed a nonlinear decrease in the log-scale plasma concentrations. Treatment was only supportive and involved prolonged sedation to control the agitation, sleeplessness, and hypertension; no cyproheptadine was used. The patient was discharged on day 6 and follow-up revealed no sequelae. CONCLUSION: To our knowledge, this is the first report of SS after sibutramine overdose in a child, with sequential monitoring of the plasma levels of the drug and its two active metabolites. The growing consumption of weight reducing pills may increase the risk of unintentional acute toxic exposures in children.


Asunto(s)
Depresores del Apetito/envenenamiento , Ciclobutanos/envenenamiento , Síndrome de la Serotonina/inducido químicamente , Antídotos/administración & dosificación , Depresores del Apetito/análisis , Preescolar , Hidrato de Cloral/administración & dosificación , Cromatografía Líquida de Alta Presión , Creatina Quinasa/sangre , Ciclobutanos/sangre , Diazepam/administración & dosificación , Sobredosis de Droga/terapia , Femenino , Humanos , Midazolam/administración & dosificación , Síndrome de la Serotonina/fisiopatología , Síndrome de la Serotonina/terapia , Espectrometría de Masa por Ionización de Electrospray
13.
Electrophoresis ; 30(12): 2238-44, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19582724

RESUMEN

In this work, a simple method for the simultaneous determination of cocaine (COC) and five COC metabolites (benzoylecgonine, cocaethylene (CET), anhydroecgonine, anhydroecgonine methyl ester and ecgonine methyl ester) in human urine using CE coupled to MS via electrospray ionization (CE-ESI-MS) was developed and validated. Formic acid at 1 mol/L concentration was used as electrolyte whereas formic acid at 0.05 mol/L concentration in 1:1 methanol:water composed the coaxial sheath liquid at the ESI nozzle. The developed method presented good linearity in the dynamic range from 250 ng/mL to 5000 ng/mL (coefficient of determination greater than 0.98 for all compounds). LODs (signal-to-noise ratio of 3) were 100 ng/mL for COC and CET and 250 ng/mL for the other studied metabolites whereas LOQ's (signal-to-noise ratio of 10) were 250 ng/mL for COC and CET and 500 ng/mL for all other compounds. Intra-day precision and recovery tests estimated at three different concentration levels (500, 1500 and 5000 ng/mL) provided RSD lower than 10% (except anhydroecgonine, 18% RSD) and recoveries from 83-109% for all analytes. The method was successfully applied to real cases. For the positive urine samples, the presence of COC and its metabolites was further confirmed by MS/MS experiments.


Asunto(s)
Cocaína/análogos & derivados , Cocaína/orina , Electroforesis Capilar/métodos , Espectrometría de Masas/métodos , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
14.
J Chromatogr A ; 1171(1-2): 140-3, 2007 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-17919649

RESUMEN

The aim of this work was to develop a fast method using capillary electrophoresis for the determination of creatinine in human urine samples. The pH and constituents of the background electrolyte were selected by inspection of effective mobility of creatinine and candidate urine interferents versus pH curves. The tendency of the analyte to undergo electromigration dispersion and the buffer capacity were evaluated by the Peakmaster software and considered in the optimization of the background electrolyte, composed by 10 mmol L(-1) tris(hydroxymethyl)aminomethane and 20 mmol L(-1) 2-hydroxyisobutyric acid (HIBA) at pH 3.93. Separation was conducted in a fused-silica capillary (32 cm total length and 8.5 cm effective length, 50 microm I.D.), with short-end injection configuration and direct UV detection at 215 nm. The migration time of creatinine was only 22s. A few figures of merit of the method are as follows: good linearity in the concentration interval of 5-70 mg L(-1) (R(2)>0.99), limit of detection of 0.5 mg L(-1), inter-day precision better than 2.7% (n=9) and recovery in the range 99.0-103.7% at three concentration levels (50, 100 and 150 mg L(-1)). Urine samples were prepared by deproteination with acetonitrile (1:3 sample:acetonitrile, v/v), centrifugation and dilution of a deproteinated aliquot with 12.5 mmol L(-1) HIBA (1:4, v/v). Creatinine concentrations between 489 and 1063 mg L(-1) were obtained in the urine of four healthy volunteers.


Asunto(s)
Creatinina/orina , Electroforesis Capilar/métodos , Electrólitos/química , Humanos , Concentración de Iones de Hidrógeno , Hidroxibutiratos/química , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrofotometría Ultravioleta/métodos , Trometamina/química
15.
Forensic Sci Int ; 173(2-3): 130-6, 2007 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-17376619

RESUMEN

The consumption of synthetic drugs, generally known as designer drugs, has increased drastically in all parts of the world. Typical constituents of designer synthetic drugs are chemical substances derived from amphetamine but significant differences in effects caused and duration may result. In May, 2005, the civil state police of Sao Paulo seized thirty-one gelatinous capsules containing a very small quantity of a white powder inside (approximately 1.5 mg per capsule). This paper describes the analytical assays that were used to identify the seized material. Preliminary assays using colorimetric tests and high performance thin-layer chromatography indicated that the capsules content could be an amphetamine derivative. In the capillary zone electrophoresis assay, it was possible to observe that the analyzed material had basic characteristics. Mass spectrometry analysis revealed that the compound had the same molecular mass as 2,5-dimethoxy-4-bromoamphetamine (DOB) and its identity was confirmed through collision-induced dissociation (CID) experiments. Finally, the comparison of infrared sample spectrum with a spectra library provided further evidence of the DOB presence in the seized material. Although a reference standard material was not available, the information gathered from the different assays allowed the conclusion that the substance was, in fact, DOB, a substance with a powerful hallucinogenic action of proscribed use in the country and which was seized and identified for the first time in Brazil.

16.
Artículo en Inglés | MEDLINE | ID: mdl-15458720

RESUMEN

This paper describes the development and validation of analytical methodology for the determination of the use of MDMA, MDEA and MDA in urine. After a simple liquid extraction, the analyses were carried out on a high performance liquid chromatography (HPLC) in an octadecyl column, with fluorescence detection. The mobile phase using a sodium dodecyl sulfate ion-pairing reagent allows good separation and efficiency. The method showed good linearity and precision. Recovery was between 85 and 102% and detection limits were 10, 15 and 20 ng/ml for MDA, MDMA and MDEA, respectively. No interfering substances were detected with fluorescence detection.


Asunto(s)
3,4-Metilenodioxianfetamina/análogos & derivados , 3,4-Metilenodioxianfetamina/orina , Cromatografía Líquida de Alta Presión/métodos , N-Metil-3,4-metilenodioxianfetamina/orina , Espectrometría de Fluorescencia/métodos , Medicina Legal , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
17.
Avian Pathol ; 32(2): 213-6, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12745374

RESUMEN

A Mycoplasma synoviae (MS)-free flock of broiler breeders was housed for brooding and rearing on an MS endemic farm. PCR revealed that the flock became infected within nine weeks. At 22 weeks the flock was transferred to a clean and disinfected house on a previously depopulated farm. The birds were then subjected to three treatments with fluoroquinolones due to recurrent Escherichia coli peritonitis and from the 32 weeks of age they received 600 ppm of oxytetracycline hydrochloride continuously in the feed. Monitoring by PCR showed a decrease in MS positive birds after 34 weeks of age and MS may have been eradicated as judged by consistent negative results in PCR. We conclude that intensive antibiotic treatments supported by adequate biosecurity could clear MS from infected broiler breeders.


Asunto(s)
Antibacterianos/uso terapéutico , Antiinfecciosos/uso terapéutico , Pollos , Infecciones por Escherichia coli/veterinaria , Infecciones por Mycoplasma/veterinaria , Enfermedades de las Aves de Corral/epidemiología , Crianza de Animales Domésticos/métodos , Animales , Brasil/epidemiología , Brotes de Enfermedades/prevención & control , Brotes de Enfermedades/veterinaria , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/prevención & control , Femenino , Fluoroquinolonas , Higiene , Masculino , Mycoplasma/efectos de los fármacos , Mycoplasma/aislamiento & purificación , Infecciones por Mycoplasma/tratamiento farmacológico , Infecciones por Mycoplasma/epidemiología , Oxitetraciclina/uso terapéutico , Peritonitis/tratamiento farmacológico , Peritonitis/microbiología , Peritonitis/veterinaria , Reacción en Cadena de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa/veterinaria , Enfermedades de las Aves de Corral/tratamiento farmacológico
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