Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Acta Crystallogr C Struct Chem ; 80(Pt 4): 91-97, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38441142

RESUMO

A confiscated package of street drugs was characterized by the usual mass spectral (MS) and FT-IR analyses. The confiscated powder material was highly crystalline and was found to consist of two very different species, accidentally of sizes convenient for X-ray diffraction. Thus, one each was selected and redundant complete sets of data were collected at 100 K using Cu Kα radiation. The selected crystals contained: (a) 1,2-diphenyl-2-(pyrrolidin-1-yl)ethanone hydrochloride hemihydrate or 1-(2-oxo-1,2-diphenylethyl)pyrrolidin-1-ium chloride hemihydrate, C18H20NO+·Cl-·0.5H2O, (I), a synthetic cathinone called `α-D2PV', and (b) the sugar myo-inositol, C6H12O6, (II), probably the only instance in which the drug and its diluent have been fully characterized from a single confiscated sample. Moreover, the structural details of both are rather attractive showing: (i) interesting hydrogen bonding observed in pairwise interactions by the drug molecules, mediated by the chloride counter-anions and the waters of crystallization, and (ii) π-π interactions in the case of the phenyl rings of the drug which are of two different types, namely, π-π stacking and edge-to-π. Finally, the inositol crystallizes with Z' = 2 and the resulting diastereoisomers were examined by overlay techniques.

2.
Front Zool ; 20(1): 23, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37464371

RESUMO

BACKGROUND: Bats are increasingly being recognized as important hosts for viruses, some of which are zoonotic and carry the potential for spillover within human and livestock populations. Biosurveillance studies focused on assessing the risk of pathogen transmission, however, have largely focused on the virological component and have not always considered the ecological implications of different species as viral hosts. The movements of known viral hosts are an important component for disease risk assessments as they can potentially identify regions of higher risk of contact and spillover. As such, this study aimed to synthesize data from both virological and ecological fields to provide a more holistic assessment of the risk of pathogen transmission from bats to people. RESULTS: Using radiotelemetry, we tracked the small-scale movements of Rousettus aegyptiacus, a species of bat known to host Marburg virus and other viruses with zoonotic potential, in a rural settlement in Limpopo Province, South Africa. The tracked bats exhibited seasonal variations in their movement patterns including variable usage of residential areas which could translate to contact between bats and humans and may facilitate spillover. We identified a trend for increased usage of residential areas during the winter months with July specifically experiencing the highest levels of bat activity within residential areas. July has previously been identified as a key period for increased spillover risk for viruses associated with R. aegyptiacus from this colony and paired with the increased activity levels, illustrates the risk for spillover to human populations. CONCLUSION: This study emphasizes the importance of incorporating ecological data such as movement patterns with virological data to provide a better understanding of the risk of pathogen spillover and transmission.

3.
Acta Crystallogr C Struct Chem ; 72(Pt 1): 48-51, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26742826

RESUMO

α-Pyrrolidinovalerophenone (α-PVP), a dangerous designer drug, is now being marketed around the world as a harmless `bath salt', when in reality it is a powerful ß-ketone phenethylamine stimulant. A sample of the free base from a recent law-enforcement seizure was crystallized as the HCl salt [systematic name: 1-(1-oxo-1-phenylpentan-2-yl)pyrrolidin-1-ium chloride 0.786-hydrate], C15H22NO(+)·Cl(-)·0.786H2O. In the crystal structure, the propyl chain is nearly perpendicular to both the phenyl ring and the carbonyl group. The hydrogen-bonding scheme involves the quaternary N atom, the Cl(-) anion and the partially occupied (0.786) water molecule, forming centrosymmetric dimers.


Assuntos
Ânions/química , Estimulantes do Sistema Nervoso Central/química , Estimulantes do Sistema Nervoso Central/síntese química , Drogas Desenhadas/química , Drogas Desenhadas/síntese química , Drogas Ilícitas/química , Drogas Ilícitas/síntese química , Oniocompostos/síntese química , Fenetilaminas/química , Pirrolidinas/química , Pirrolidinas/síntese química , Sais/química , Sais/síntese química , Cristalografia por Raios X , Ligação de Hidrogênio , Oniocompostos/química , Fenetilaminas/farmacologia
4.
J Strength Cond Res ; 30(5): 1397-408, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26439778

RESUMO

Strongman training (ST) has become an increasingly popular modality, but data on physiological responses are limited. This study sought to determine physiological responses to an ST session compared to a traditional strength exercise training (RST) session. Ten healthy men (23.6 ± 27.5 years, 85.8 ± 10.3 kg) volunteered in a crossover design, where all participants performed an ST session, an RST session, and a resting session within 7 days apart. The ST consisted of sled drag, farmer's walk, 1 arm dumbbell clean and press, and tire flip at loads eliciting approximately 30 seconds of near maximal effort per set. The RST consisted of squat, deadlift, bench press, and power clean, progressing to 75% of 1 repetition maximum. Sessions were equated for approximate total set duration. Blood lactate and salivary testosterone were recorded immediately before and after training sessions. Heart rate, caloric expenditure, and substrate utilization were measured throughout the resting session, both training protocols and for 80 minutes after training sessions. Analyses were conducted to determine differences in physiological responses within and between protocols. No significant changes in testosterone occurred at any time point for either session. Lactate increased significantly immediately after both sessions. Heart rate, caloric expenditure, and substrate utilization were all elevated significantly during ST and RST. Heart rate and fat expenditure were significantly elevated compared to resting in both sessions' recovery periods; calorie and carbohydrate expenditures were not. Compared to RST, ST represents an equivalent physiological stimulus on key parameters indicative of potential training-induced adaptive responses. Such adaptations could conceivably include cardiovascular conditioning.


Assuntos
Exercício Físico/fisiologia , Treinamento Resistido/métodos , Adaptação Fisiológica , Adulto , Estudos Cross-Over , Metabolismo Energético/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Ácido Láctico/sangue , Masculino , Consumo de Oxigênio/fisiologia , Testosterona/metabolismo
5.
Acta Crystallogr C Struct Chem ; 71(Pt 1): 32-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25567572

RESUMO

The name `bath salts', for an emerging class of synthetic cathinones, is derived from an attempt to evade prosecution and law enforcement. These are truly illicit drugs that have psychoactive CNS (central nervous system) stimulant effects and they have seen a rise in abuse as recreational drugs in the last few years since first having been seen in Japan in 2006. The ease of synthesis and modification of specific functional groups of the parent cathinone make these drugs particularly difficult to regulate. MDPV (3,4-methylenedioxypyrovalerone) is commonly encountered as its hydrochloride salt (C16H21NO3·HCl), in either the hydrated or the anhydrous forms. This `bath salt' has various names in the US, e.g. `Super Coke', `Cloud Nine', and `Ivory Wave', to name just a few. We report here the structures of two forms of the HCl salt, one as a mixed bromide/chloride salt, C16H22NO3(+)·0.343Br(-)·0.657Cl(-) [systematic name: 1-(benzo[d][1,3]dioxol-5-yl)-2-(pyrrolidin-1-ium-1-yl)pentan-1-one bromide/chloride (0.343/0.657)], and the other with the H7O3(+) cation, as well as the HCl counter-ion [systematic name: hydroxonium 1-(benzo[d][1,3]dioxol-5-yl)-2-(pyrrolidin-1-ium-1-yl)pentan-1-one dichloride, H7O3(+)·C16H22NO3(+)·2Cl(-)]. This is one of a very few structures (11 to be exact) in which we have a new example of a precisely determined hydroxonium cation. During the course of researching the clandestine manufacture of MDPV, we were surprised by the fact that a common precursor of this illicit stimulant is known to be the fragrant species piperonal, which is present in the fragrances of orchids, most particularly in the case of the vanilla orchid. We found that MDPV can be made by a Grignard reaction of this heliotropin. This may also explain the unexpected appearance of the bromide counter-ion in some of the salts we encountered (C16H21NO3·HBr), one of which is presented here [systematic name: 1-(benzo[d][1,3]dioxol-5-yl)-2-(pyrrolidin-1-ium-1-yl)pentan-1-one bromide, C16H22NO3(+)·Br(-)]. Complexation of MDPV with a forensic crystallizing reagent, HAuCl4, yields the tetrachloridoaurate salt of this drug, (C16H22NO3)[AuCl4]. The heavy-metal complexing agent HAuCl4 has been used for over a century to identify common quarternary nitrogen-containing drugs via microscopic identification. Another street drug, called ethylone (3,4-methylenedioxyethylcathinone), is regularly sold and abused as its hydrochloride salt (C12H15NO3·HCl), and its structure is herein described (systematic name: N-{1-[(benzo[d][1,3]dioxol-5-yl)carbonyl]ethyl}ethanaminium chloride, C12H16NO3(+)·Cl(-)). Marketed and sold as a `bath salt', `plant feeder', or `cleaning product', this drug is nothing more than a slight chemical modification of the banned drug methylone (3,4-methylenedioxymethcathinone). As with previously popular synthetic cathinones, the abuse of ethylone has seen a recent increase due to regulatory efforts on previous generations of cathinones that are now banned.


Assuntos
Alcaloides/química , Alcaloides/síntese química , Benzaldeídos/química , Benzodioxóis/química , Benzodioxóis/síntese química , Estimulantes do Sistema Nervoso Central/química , Estimulantes do Sistema Nervoso Central/síntese química , Drogas Desenhadas/química , Drogas Ilícitas/química , Drogas Ilícitas/síntese química , Lidocaína/química , Metanfetamina/análogos & derivados , Psicotrópicos/química , Psicotrópicos/síntese química , Pirrolidinas/química , Pirrolidinas/síntese química , Sais/química , Sais/síntese química , Cristalografia por Raios X , Combinação de Medicamentos , Humanos , Japão , Metanfetamina/síntese química , Metanfetamina/química , Transtornos Relacionados ao Uso de Substâncias , Catinona Sintética
6.
Acta Crystallogr C ; 69(Pt 4): 388-93, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23579713

RESUMO

The ortho-metallation product of the reaction of (±)-amphetamine with gold(III) chloride, [D,L-2-(2-aminopropyl)phenyl-κ(2)N,C(1)]dichloridogold(III), [Au(C9H12N)Cl2], and the two salts resulting from crystallization of (+)-methamphetamine with gold(III) chloride, D-methyl(1-phenylpropan-2-yl)azanium tetrachloridoaurate(III), (C10H16N)[AuCl4], and of (±)-ephedrine with gold(III) chloride, D,L-(1-hydroxy-1-phenylpropan-2-yl)(methyl)azanium tetrachloridoaurate(III), (C10H16NO)[AuCl4], have different structures. The first makes a bidentate complex directly with a dichloridogold(III) group, forming a six-membered ring structure; the second and third each form a salt with [AuCl4](-) (each has two formula units in the asymmetric unit). The organic components are all members of the same class of stimulants that are prevalent in illicit drug use. These structures are important contributions to the understanding of the microcrystal tests for these drugs that have been employed for well over 100 years.


Assuntos
Efedrina/química , Compostos de Ouro/química , Ouro/química , Metanfetamina/química , Fenetilaminas/química , Anfetaminas , Cristalografia por Raios X , Modelos Moleculares , Estrutura Molecular , Sais
7.
Acta Crystallogr C ; 66(Pt 1): m4-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20048413

RESUMO

The structure of the hydrated gold(III) tetrachloride salt of L-ecgonine {hydronium tetrakis[(1R,2R,3S,5S,8S)-3-hydroxy-8-methyl-8-azoniabicyclo[3.2.1]octane-2-carboxylate pentakis[tetrachloridoaurate(III)] hexahydrate}, (C(9)H(16)NO(3))(4)(H(3)O)[AuCl(4)](5).6H(2)O, demonstrates an unprecedented stoichiometric relationship between the cations and anions in the unit cell. The previous tropane alkaloid structures, including the related hydrochloride salts, all have a cation-anion ratio of 1:1, as does the anhydrous salt described here, namely (1R,2R,3S,5S,8S)-3-hydroxy-8-methyl-8-azoniabicyclo[3.2.1]octane-2-carboxylate tetrachloridoaurate(III), (C(9)H(16)NO(3))[AuCl(4)]. The hydrated salt, however, consists of four monopositive N-protonated units of the alkaloid and five [AuCl(4)](-) counter-ions, plus seven solvent water molecules. The H atom required for change balance has been assigned to a water molecule. In addition, the hydrate has a novel arrangement, with all seven of the water molecules and all of the O atoms in the cations participating in an alternating arrangement of interleaved sheets of the anionic species. Both the hydrate and the anhydrous salt of the same toxicologically important marker for cocaine show that the cation and anion are in close proximity to each other, as was found in the gold(III) tetrachloride salt of L-cocaine.


Assuntos
Cocaína/análogos & derivados , Cocaína/química , Compostos de Ouro/química , Cocaína/sangue , Cristalografia por Raios X , Toxicologia Forense/métodos , Compostos de Ouro/sangue , Humanos , Estrutura Molecular , Sais , Água/química
8.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 2): o525, 2008 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-21201544

RESUMO

The title compound, (1R,2R,3S,5S,8S)-3-hydr-oxy-8-methyl-8-azoniabicyclo-[3.2.1]octane-2-carboxylic acid chloride, C(9)H(16)NO(3) (+)·Cl(-), is both a metabolite and a precursor of the tropane alkaloid l-cocaine. The carboxyl group is not involved in dimerization, but instead donates a hydrogen bond to the chloride counter-ion, which participates in two additional hydrogen bonds. The chloride ion is thus trigonally hydrogen bonded to three l-ecgonine cations. The quarternary N proton is intra-molecularly hydrogen bonded to the carboxyl C=O group, an arrangement identical to that reported for both (-)-nor-cocaine and the tetrachloroaurate(III) salt of l-cocaine. One close inter-molecular C-H⋯O contact exists.

9.
J Sci Med Sport ; 11(6): 593-9, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17719848

RESUMO

Team-sport athletes who normally reside at sea level occasionally play games at altitudes sufficient to impair endurance performance. To investigate the effect of intermittent normobaric hypoxic exposure on performance in generic and game-specific tests at altitude, 22 senior club level rugby players performed baseline tests before single-blind random assignment to one of three groups: hypoxia-altitude (n=9), normoxia-altitude (n=6), and normoxia-sea level (n=7). The hypoxia-altitude group underwent 9-13 sessions of intermittent hypoxic exposure (concentration of inspired oxygen=13-10%) over 15 days, then repeated the performance tests within 12h of travelling to 1550m. The normoxia-altitude group underwent placebo exposures by breathing room air before repeating the tests at altitude, whereas the normoxia-sea level group underwent placebo exposures before repeating the tests at sea level. Hypoxic exposure consisted of alternately breathing 6min hypoxic gas and 4min ambient air for 1h at rest. Performance measures gathered at each testing session were maximum speed, sub-maximum heart-rate speed and sub-maximum lactate speed during a 20-m incremental running test, mean time in six 70-m sprints, repetitive explosive power and other measures from seven 5.5-min circuits of a rugby simulation. Repetitive explosive power ( approximately -16%) and 20-m shuttle performance ( approximately -3%) decreased substantially at altitude compared to sea level. Acclimatisation to hypoxia had a beneficial effect on sub-maximum heart rate and lactate speed but little effect on other performance measures. In conclusion, 1550-m altitude substantially impaired some measures of performance and the effects of prior adaptation via 9-13 sessions of intermittent hypoxia were mostly unclear.


Assuntos
Aclimatação/fisiologia , Altitude , Futebol Americano , Hipóxia/prevenção & controle , Adolescente , Atitude , Humanos , Resistência Física , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...