RESUMEN
3-Quinuclidinyl benzilate (BZ) ranks among incapacitating military warfare agents. It acts as a competitive inhibitor on muscarinic receptors leading to non-lethal mental impairment. The present study aimed to investigate toxicokinetics of BZ in rats. Moreover, BZ can be exploited to produce a pharmacological model of Alzheimer's disease; thus, this paper focuses mainly on the BZ distribution to the brain. Wistar rats were administered i.p. with BZ (2 and 10 mg/kg). The BZ concentration was determined using LC-MS/MS in plasma, urine, bile, brain, kidney and liver. The sample preparation was based on a solid phase extraction (liquids) or protein precipitation (organ homogenates). The plasma concentration peaked at 3 min (204.5 ± 55.4 and 2185.5 ± 465.4 ng/ml). The maximal concentration in the brain was reached several minutes later. Plasma elimination half-life was 67.9 ± 3.4 in the 2 mg/kg group and 96.6 ± 27.9 in the 10 mg/kg group. BZ concentrations remained steady in the brain, with slow elimination (t1/2 506.9 ± 359.5 min). Agent BZ is excreted mainly via the urine. Steady BZ concentration in the brain could explain the previously published duration of the significant impairment in passive avoidance tasks in rats after an injection of BZ.
Asunto(s)
Antagonistas Muscarínicos/metabolismo , Antagonistas Muscarínicos/toxicidad , Quinuclidinil Bencilato/metabolismo , Quinuclidinil Bencilato/toxicidad , Animales , Bilis/metabolismo , Encéfalo/metabolismo , Masculino , Metaboloma , Antagonistas Muscarínicos/sangre , Antagonistas Muscarínicos/orina , Quinuclidinil Bencilato/sangre , Quinuclidinil Bencilato/orina , Ratas , Ratas Wistar , Toxicocinética , OrinaRESUMEN
3-Quinuclidinyl benzilate (QNB) is an anticholinergic compound that affects the nervous system. Its hallucinogenic action has led to its potential utility as an incapacitating warfare agent, and it is listed in Schedule 2 by the Organization for the Prohibition of Chemical Weapons. Although this compound has been known for a long time, limited information is available regarding its metabolism and mass spectrometric data of the metabolites, the information that could facilitate the identification of QNB in case of suspected intoxication. To the best of our knowledge, the analytical methods previously described in the literature are based on outdated procedures, which may result in a significantly lower number of observable metabolites. The aim of this work was to obtain deeper insight into QNB biotransformation using a combination of in vitro and in vivo approach. The development of a suitable method for the separation and detection of metabolites using mass spectrometry together with the identification of reliable diagnostic fragments for the unambiguous identification of QNB metabolites in the different biological matrices are also presented in this work. A screening of rat plasma, urine and tissue homogenates revealed 26 new metabolites related to the cytochrome P450 biotransformation pathway, which involves N-oxidation and hydroxylation(s) followed by O-methylation and O-glucuronosylation within phase II of the metabolism. A study showed that the brain is not metabolically active in the case of QNB and that the metabolites do not cross the blood-brain barrier; thus, the toxicodynamic effects are due to QNB itself. In addition, in vitro experiments performed using isolated human liver microsomes revealed N-oxidation as the principal metabolic pathway in human tissue. In light of current global events, the abuse of QNB by terrorists or para-military groups is a real possibility, and our findings may improve the detection systems used in laboratories involved in postexposure investigations.
Asunto(s)
Encéfalo , Animales , Biotransformación , Espectrometría de Masas , Quinuclidinil Bencilato , RatasRESUMEN
Agent BZ (3-quinuclidinyl benzilate) is a centrally acting synthetic anticholinergic agent, considered as a potential military incapacitating chemical warfare agent. Despite its significance as a model compound in pharmacological research and its potential misuse in chemical attacks, few modern analytical methods for BZ determination in biological samples have been published. The goal of the present work is to develop and validate a sensitive and rapid LC-MS/MS method for the determination of agent BZ in rat plasma. The sample preparation was based on solid-phase extraction on C-18 cartridges. The reversed-phase HPLC coupled with the mass spectrometer with electrospray ionization in the positive ion-selective reaction monitoring mode was employed in the BZ analysis. Atropine was used as an internal standard. The presented method is selective, accurate, precise, and linear (r2 = 0.9947) in a concentration range from 0.5 ng/mL to 1 000 ng/mL and sensitive enough (limit of detection 0.2 ng/mL; limit of quantification 0.5 ng/mL) to determine the BZ plasma levels in rats exposed to 2 mg/kg and 10 mg/kg of BZ. The highest level of BZ in plasma was observed 5 minutes after intramuscular administration (154.6 ± 22.3 ng/mL in rats exposed to 2 mg/kg of BZ and 1024 ± 269 ng/mL in rats exposed to 10 mg/kg). After 48 h, no BZ was observed at detectable levels. This new method allows the detection and quantification of BZ in biological samples after exposure of an observed organism and it will be further optimized for other tissues to observe the distribution of BZ in organs.
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Antagonistas Colinérgicos/sangre , Quinuclidinil Bencilato/sangre , Animales , Antagonistas Colinérgicos/análisis , Cromatografía Líquida de Alta Presión , Límite de Detección , Masculino , Quinuclidinil Bencilato/análisis , Ratas , Ratas Wistar , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en TándemRESUMEN
This replication of a study by >Rutchick, Slepian, and Ferris (2010) examines the influence of the colour of a pen on the activation of associations with failure and the focus on errors. We assigned two tasks to 198 students who completed them using either a red or a blue pen. The students were instructed to complete several word stems in the first task. In the second, we asked them to mark mistakes in a text. The participants using red pens completed significantly more word stems with words associated with failure than those using blue pens. The participants using red pens also marked significantly more mistakes in a text than those using blue pens. Our results support the findings of the original study and the hypothesized influence of the colour red in inducing a higher activation of associations with failure and a heightened focus on mistakes. Our study further contributes to research in this area in that it takes into account the participants' field of study and creates an explicit achievement context in which the observed phenomenon is most prevalent.
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Logro , Percepción de Color/fisiología , Color , Adolescente , Adulto , Femenino , Humanos , Masculino , Distribución Aleatoria , Adulto JovenRESUMEN
INTRODUCTION: Chlamydia psittaci is an obligate intracellular Gram-negative bacterium causing respiratory disease (chlamydiosis) or asymptomatic carriage in poultry. In humans, it is a zoonotic agent of ornithosis/psittacosis. Due to low awareness of the disease and variable clinical presentation, psittacosis is often remains unrecognised as such by general practitioners. Zoonotic transfer occurs through inhalation of contaminated aerosols, and originates from feathers, faecal material and respiratory tract exudates. OBJECTIVE: The aim of this study was to investigate chickens for the presence of Chlamydia sp. from pharyngeal and cloacal swabs and review the zoonotic risk for humans. MATERIAL AND METHODS: 138 clinically healthy chickens from farms in Slovakia were examined for the presence of Chlamydia sp. The age of the chickens was 6 months. Two different samples were used - pharyngeal swabs and cloacal swabs. Each sample was examined by the molecular PCR method, and in the case of a positive result the identity of the obtained sequences was examined by a BLAST search. RESULTS: Of the total number of 276 examined samples from 138 chickens, 19 (6.9%) showed positivity for C. psittaci infection, 12 (8.7%) which were positive from pharyngeal swabs and 7 (5.1%) from cloacal swabs. None of the chickens were positive in both samples. Phylogenetic examination of the 19 isolates identified in the study, based on the 23S rRNA gene sequence, revealed that the isolates obtained were identical with C. psittaci, and genetically very close to genotypes B and genotype E. CONCLUSIONS: C. psittaci infections are apparently emerging in chickens. Chicken-processing plant employees should be considered a risk group for human psittacosis. There is a need for higher awareness and for efficient risk assessment and management.
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Chlamydophila psittaci/aislamiento & purificación , Enfermedades de las Aves de Corral/microbiología , Psitacosis/microbiología , Psitacosis/veterinaria , Zoonosis/microbiología , Animales , Pollos/microbiología , Chlamydophila psittaci/clasificación , Chlamydophila psittaci/genética , Genotipo , Humanos , Filogenia , Psitacosis/transmisión , Eslovaquia , Zoonosis/transmisiónRESUMEN
The aim of the study was to explore sexual behaviour and the occurrence of Chlamydia trachomatis (CT) infection in the population living in Roma settlements compared to the majority population in Slovakia and to assess the association between alcohol use and sexual behaviour within both populations. A cross-sectional population-based Hepa-Meta study was conducted in Slovakia in 2011. The final sample comprised 452 Roma and 403 non-Roma respondents. The occurrence of CT was detected by direct proof of the pathogen by PCR. The association between alcohol use and the prevalence of risky sexual behaviour were assessed using a logistic regression. First intercourse at age 15 or younger was reported by 27.9% of Roma (vs. 4.5% of non-Roma); 93.4% of Roma (vs. 77.9% of non-Roma) used condom inconsistently, 22.8% of Roma (vs. 43.9% of non-Roma) used a condom for protection from unwanted pregnancies and only 8.8% of Roma (vs. 21.8% of non-Roma) due to protection against infectious diseases. However, Roma reported having had five or more sexual partners less often compared to the majority (11.5% of Roma vs. 20.6% of non-Roma). Binge drinking at least once a month was associated with a higher number of sexual partners in both groups, but not with condom non-use. The prevalence of CT infection in the Roma population was higher (3.8%) compared to non-Roma (2.7%); however, the difference was not statistically significant. Our study found no differences in the prevalence of CT infection between Roma and non-Roma despite differences in sexual behaviour. Roma begin their sexual life earlier and have unprotected sex more often, but on the other hand, they seem to be much more restrained in terms of the number of sexual partners compared to the majority population.
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Consumo de Bebidas Alcohólicas/epidemiología , Infecciones por Chlamydia/epidemiología , Chlamydia trachomatis , Conducta Sexual , Segregación Social , Adulto , Consumo de Bebidas Alcohólicas/etnología , Infecciones por Chlamydia/etnología , Estudios Transversales , Femenino , Humanos , Masculino , Prevalencia , Factores de Riesgo , Romaní/estadística & datos numéricos , Eslovaquia/epidemiologíaRESUMEN
INTRODUCTION AND OBJECTIVES: Chlamydia psittaci, an obligate intracellular bacterium, which is the etiologic agent of avian chlamydiosis in birds and ornithosis/psittacosis in humans, has been reported to be one of the most common pathogens found in feral pigeons worldwide, and thus constitutes a zoonotic risk. The aim of the study was to investigate pigeons in Slovakia living in areas in close proximity to humans for the presence of C. psittaci, using pharyngeal and cloacal swabs. MATERIAL AND METHODS: 122 clinically healthy pigeons from different geographical regions of Slovakia were examined for the presence of C. psittaci. The adult pigeons of both genders were captured during the summer period in the urban centres of Slovakian towns. Each sample was examined by molecular method PCR, and in the case of positive result the identity of the obtained sequence was examined by a BLAST search. RESULTS: Of the total number of 244 examined samples, 14 (5.7%) showed positivity for C. psittaci infection, 5 of which were from pharyngeal swabs (4.1%) and 9 from cloacal swabs (7.4%). A positive result was detected in 13 pigeons (10.7%). Phylogenetic analysis showed that all the positive samples are genetically very close to genotypes B and genotype E. CONCLUSION: Phylogenetic examination of the 14 isolates of C. psittaci identified in the presented study, based on 23S rRNA gene sequence, revealed their close relationship with C. psittaci genotypes B and E. Both genotypes are predominantly prevalent in pigeons and both can be transmitted to humans. Therefore, it is necessary to perform screening examinations of animals and analyse the epidemiological factors affecting the way of transmission and circulation of pathogen.