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1.
Viruses ; 9(8)2017 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-28749451

RESUMEN

Although smallpox has been known for centuries, the oldest available variola virus strains were isolated in the early 1940s. At that time, large regions of the world were already smallpox-free. Therefore, genetic information of these strains can represent only the very last fraction of a long evolutionary process. Based on the genomes of 48 strains, two clades are differentiated: Clade 1 includes variants of variola major, and clade 2 includes West African and variola minor (Alastrim) strains. Recently, the genome of an almost 400-year-old Lithuanian mummy was determined, which fell basal to all currently sequenced strains of variola virus on phylogenetic trees. Here, we determined two complete variola virus genomes from human tissues kept in a museum in Prague dating back 60 and 160 years, respectively. Moreover, mass spectrometry-based proteomic, chemical, and microscopic examinations were performed. The 60-year-old specimen was most likely an importation from India, a country with endemic smallpox at that time. The genome of the 160-year-old specimen is related to clade 2 West African and variola minor strains. This sequence likely represents a new endemic European variant of variola virus circulating in the midst of the 19th century in Europe.


Asunto(s)
Genoma Viral , Museos , Viruela/virología , Virus de la Viruela/genética , República Checa , ADN Viral/genética , Europa (Continente)/epidemiología , Evolución Molecular , Secuenciación de Nucleótidos de Alto Rendimiento , Historia del Siglo XIX , Historia del Siglo XX , Humanos , India/epidemiología , Filogenia , Reacción en Cadena de la Polimerasa , Proteómica , Viruela/epidemiología , Viruela/historia , Virus de la Viruela/clasificación
2.
Int J Legal Med ; 126(4): 519-24, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21751026

RESUMEN

Ibotenic acid and muscimol are substances which mostly participate in psychotropic properties of Amanita pantherina and Amanita muscaria. They are rapidly absorbed from the gastrointestinal tract and readily excreted in urine. The poisoning with A. pantherina is in the majority of cases accidental because it can be easily mistaken for the edible species (Amanita rubescens, Amanita spissa and Macrolepiota procera). Intoxication with A. muscaria is mostly intentional for recreational purposes. Prognosis of the poisoning is generally good; lethal cases are rare. Mushroom poisoning is often proved by microscopic examination of spores in the stomach or intestinal content. Authors of this article introduce an instrumental method of proving A. pantherina or A. muscaria poisoning. The article describes the isolation of ibotenic acid and muscimol from urine, the derivatization step and the determination of these compounds by gas chromatography/mass spectrometry. Isolation of these alkaloids from urine was performed on a strong cation exchanger (Dowex® 50W X8), and the elution and derivatization of the alkaloids were made in one step with ethyl chloroformate in aqueous solution of sodium hydroxide with the addition of ethanol and pyridine. Cycloserine was used as internal standard. By this method, concentrations of ibotenic acid and muscimol in the urine of four persons intoxicated with A. pantherina were determined. In this study, mass spectra of derivatized ibotenic acid and muscimol are shown, and validation of the method is described.


Asunto(s)
Amanita/química , Ácido Iboténico/orina , Muscimol/orina , Intoxicación por Setas/diagnóstico , Psicotrópicos/orina , Adulto , Anciano , Femenino , Toxicología Forense , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Persona de Mediana Edad , Intoxicación por Setas/orina
3.
J Chromatogr B Analyt Technol Biomed Life Sci ; 879(25): 2549-53, 2011 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-21803666

RESUMEN

A liquid chromatography-mass spectrometry based method for determination of muscarine in human urine was developed and validated. The method involved a solid phase extraction of muscarine from urine using Strata X-CW column. Separation of muscarine was achieved within 16.0 min on a reversed phase Gemini C18 analytical column (150 mm × 2.0mm i.d., 5 µm) with a mobile phase consisted of aqueous 8 mmol/L heptafluorobutyric acid and acetonitrile in a gradient mode. Mass spectrometric detection was performed at m/z 174 and m/z 216 for muscarine and acetylmuscarine (internal standard), respectively. The linearity was satisfactory with a coefficient of determination (R(2)) 0.9993 at concentration range from 0.3 ng/mL to 2.0 µg/mL, LOD and LOQ for muscarine was 0.09 ng/mL and 0.3 ng/mL, respectively. The found out recoveries of muscarine were 96% or 95% for concentration 0.3 ng/mL and 0.2 µg/mL or 2.0 µg/mL, respectively. The precision in the intra-assay-study varied from 0.48% to 1.39% and in the inter-assay-study from 2.39% to 5.49%. The accuracy ranged from -3.3% to -6%. The validation results demonstrated that the method fulfilled satisfactory requirements for precision and accuracy across the calibration curve. The applicability of the method has been demonstrated by analyzing clinical urine samples. The method offers the fast objective identification of intoxication by muscarine and can become a routine screening alternative to more difficult microscopic examination of spores in the gastric content in clinical practice.


Asunto(s)
Cromatografía de Fase Inversa/métodos , Muscarina/orina , Espectrometría de Masa por Ionización de Electrospray/métodos , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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