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1.
Food Chem ; 329: 127142, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32521426

RESUMO

In this work, we investigate alternative quantification methods based on optical spectroscopy and variable selection approach, using as a case study the aging process of cachaça. The cachaça was aged in an Amburana barrel and the samples were analyzed with a traditional analytical method for total phenolic quantification (Folin-Ciocalteu), with 2-D fluorescence and infrared spectroscopy. We applied a methodology based on Ant Colony Optimization to optimize variable selection and model fitting to predict total phenolic content. Our results demonstrated that fluorescence spectroscopy was more sensitive than IR in the quantification of total phenolic compounds for both global and local models, presenting good results (R2 superior to 0.979), significantly reducing the number of original variable (1995) for only 4 pairs of Ex/Em. Variable selection combined with spectroscopy reveals potential because this technique eliminates the need for sample preparation and allows the construction of customized sensors for application in the food industry.


Assuntos
Bebidas Alcoólicas/análise , Fenóis/química , Fluorescência , Extratos Vegetais/química , Espectrometria de Fluorescência , Espectrofotometria Infravermelho , Fatores de Tempo
2.
Food Chem ; 294: 565-571, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31126501

RESUMO

Raman spectroscopy is a rapid and non-destructive analytical technique that has found a growing interest in the characterization and quantification of microconstituents in foods. In this work, Raman spectroscopy was used to evaluate the carotenoids content of processed Bunchosia glandulifera, a native fruit from the Brazilian Atlantic Forest. The B. glandulifera pulps were dried in hot air at 65 and 85 °C, resulting in carotenoids degradation of about 75 and 80%, respectively. The degradation profile of carotenoids over time was analyzed by Raman spectroscopy, with and without the use of an internal standard (TiO2). The reproducibility of the analyses was evaluated by PCA of spectral data. PLS regression was applied for modelling the total carotenoids in B. glandulifera. Resulting models show the Raman data correlate with carotenoids content on samples resulting in a satisfactory coefficient of determination for all sets of samples.


Assuntos
Carotenoides/análise , Malpighiaceae/química , Análise Espectral Raman , Brasil , Dessecação , Frutas/química , Frutas/metabolismo , Análise dos Mínimos Quadrados , Malpighiaceae/metabolismo , Análise de Componente Principal , Reprodutibilidade dos Testes , Temperatura
3.
Accid Anal Prev ; 43(3): 782-7, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21376866

RESUMO

AIMS: The aims of the present study were to characterize fatal traffic accident victims in a major urban center in Brazil and their association with alcohol consumption. METHODS: Cross-sectional study of 907 fatal traffic accident victims in Sao Paulo, in 2005. RESULTS: Adult males between the ages of 25 and 54 represented the majority of cases with positive blood alcohol concentrations (BAC). Overall, males had a higher proportion of BAC and mean BAC than females. Pedestrians, particularly those with no detectable BAC, were typically older than other victims. Most accidents (total and BAC-positive) happened on weekends between midnight and 6 a.m. Considering all victims, 39.4% were positive (BAC over 0.1g/l). When only drivers (automobile, motorcycle and bicycle) were evaluated, 42.3% had BAC over the legal limit (0.6g/l). CONCLUSIONS: Alcohol is associated with nearly half of all traffic accident deaths in the city of Sao Paulo, especially for days and times associated with parties and bars (weekends between 12 a.m. and 6 a.m.).


Assuntos
Acidentes de Trânsito/mortalidade , Intoxicação Alcoólica/mortalidade , Países em Desenvolvimento , População Urbana/estatística & dados numéricos , Acidentes de Trânsito/prevenção & controle , Adolescente , Adulto , Intoxicação Alcoólica/complicações , Intoxicação Alcoólica/prevenção & controle , Brasil , Causas de Morte , Estudos Transversais , Etanol/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Adulto Jovem
4.
Addiction ; 104(12): 1998-2006, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19804456

RESUMO

AIMS: To assess the association between alcohol use and victimization by homicide in individuals autopsied at the Institute of Legal Medicine in São Paulo, Brazil. DESIGN: Cross-sectional study. SETTING: Excessive consumption of alcohol is a serious public health issue and a major factor in triggering violent situations, which suggests a strong association between alcohol ingestion and becoming a victim of homicide. PARTICIPANTS: Data from 2042 victims of homicides in 2005 were obtained from medical examiner reports. MEASUREMENTS: The victim's gender, age, ethnicity and blood alcohol concentration (BAC) were collected. The method of death and homicide circumstances, as well as the date, time and place of death were also studied. FINDINGS: Alcohol was detected in blood samples of 43% of the victims, and mean BAC levels were 1.55 +/- 0.86 g/l. The prevalence of positive BAC levels was higher among men (44.1%) than women (26.6%), P < 0.01. Firearms caused most of the deaths (78.6%), and alcohol consumption was greater among victims of homicide by sharp weapons (P < 0.01). A greater proportion of victims with positive BAC were killed at weekends compared to weekdays (56.4 and 38.5%, respectively; P < 0.01), and the correlation between homicide rates and the average BAC for the central area of the city was positive (r(s) = 0.90; P < 0.01). CONCLUSIONS: These results highlight alcohol as a contributing factor for homicide victimization in the greatest urban center in South America, supporting public strategies and future research aiming to prevent homicides and violence related to alcohol consumption.


Assuntos
Consumo de Bebidas Alcoólicas , Vítimas de Crime , Etanol/sangue , Homicídio , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Consumo de Bebidas Alcoólicas/epidemiologia , Autopsia , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , População Urbana , Adulto Jovem
5.
Arch. Clin. Psychiatry (Impr.) ; 35(supl.1): 17-20, 2008. graf, tab
Artigo em Inglês | LILACS | ID: lil-488972

RESUMO

BACKGROUND: Typically, urine and other biological tissues have been analyzed for cocaine (COC) and/or metabolites to detect COC usage. COC undergoes numerous biotransformation and degradation reactions. Crack smokers are exposed to anhydroecgonine methyl ester (AME), which can be used as an analytical marker for crack smoking. The stability of this analyte in human urine has not been studied. In the body, COC is rapidly converted to metabolites by enzymatic and chemical processes, the major urinary metabolite being benzoylecgonine (BE). OBJECTIVES: This study was carried out in order to determine the effects of time and temperature on the stability of cocaine/crack metabolites in human urine. METHODS : The stability of AME, BE and COC in urine was investigated using samples of urine stored in freezers and refrigerators. The analytes were extracted from urine using a solid-phase extraction technique and analyzed by gas chromatography-flame ionization detection method. RESULTS: COC concentrations decreased while BE concentrations increased. AME concentrations remained stable. CONCLUSIONS: The temperature and the duration of storage are decisive in COC hydrolyzing. This study suggests that AME concentrations are not correlated to either storage duration or with storage temperature and AME is more stable than COC.


CONTEXTO: Cocaína (COC) e/ou metabólitos tem sido analisados em urina e outros fluidos biológicos para se determinar o uso de COC. A COC está sujeita a numerosas reações de biotransformação e degradação. Indivíduos que fumam crack estão expostos ao éster metilanidroecgonina (AME), que pode ser empregado como marcador de uso desta droga. Não há referências na literatura a respeito da estabilidade deste analito em urina humana. No organismo a COC é rapidamente biotransformada em outros metabólitos por meio de processos químicos e enzimáticos e o principal metabólito urinário é a benzoilecgonina (BE). OBJETIVOS: O objetivo deste estudo foi determinar o efeito do tempo e da temperatura na estabilidade da COC, BE e do AME em urina humana. MÉTODOS: A estabilidade do AME, BE e COC em urina foi investigada por intermédio do armazenamento da urina em freezer e em geladeira. Os analitos foram extraídos pela técnica de extração em fase sólida e analisados por cromatografia gasosa acoplada ao detector por ionização em chama. RESULTADOS: As concentrações de COC decresceram enquanto as BE aumentaram. As concentrações de AME se mantiveram estáveis. CONCLUSÕES: A temperatura e o tempo de armazenamento são decisivos na hidrólise da COC. Este estudo sugere que as concentrações de AME não estão correlacionadas com o tempo ou a temperatura de armazenamento e o AME é mais estável que a COC.


Assuntos
Cocaína Crack , Urina
6.
RBCF, Rev. bras. ciênc. farm. (Impr.) ; 39(1): 71-75, jan.-mar. 2003. graf
Artigo em Inglês | LILACS | ID: lil-341471

RESUMO

Street drugs when in great demand in an illicit market become not only more expensive but are also subject to extensive adulteration and dilution. These fraudulent practices may also contribute to the amplification of toxic effects observed in the abuse of certain drugs including cocaine hydrochloride. The number of seizures reflects the increase of illicit use of cocaine powder in the city of S.Paulo, where the identity of the suspected drug is its hydrochloride form. Routine analytical procedures in enforcement laboratories in Brazil now comprise techniques involving thin layer chromatography for presumptive identification of the drug and eventually gas chromatography for its confirmation or quantification whenever required...


Assuntos
Anestésicos Locais/análise , Cafeína/análise , Cocaína/análise , Substâncias Tóxicas , Toxicologia , Cromatografia Gasosa , Cromatografia em Camada Fina , Espectrometria de Massas
7.
Rev. psiquiatr. clín. (São Paulo) ; 27(2): 76-82, mar.-abr. 2000.
Artigo em Português | LILACS | ID: lil-267799

RESUMO

A causa da maioria dos acidentes automobilisticos em todo o mundo tem sido ha muito associada ao consumo de alcool e, visando diminuir esses acidentes, os paises tem estabelecido limites de alcoolemia para os condutores...


Assuntos
Humanos , Etanol/análise , Consumo de Bebidas Alcoólicas/efeitos adversos , Alcoolismo/complicações , Acidentes de Trânsito
8.
Rev. Hosp. Clin. Fac. Med. Univ. Säo Paulo ; 42(2): 66-8, mar.-abr. 1987.
Artigo em Inglês | LILACS | ID: lil-42054

RESUMO

Os autores apresentaram três casos de ambigüidade genital por deficiência de 5 alfa-reductase, diagnosticada pelos níveis elevados da relaçäo T/DHT. Os pacientes mais jovens apresentaram ginecomastia leve (Tanner II), ainda näo descrita nesta síndrome. Concluimos que o desenvolvimento de ginecomastia leve pode ocorrer no pseudo-hermafroditismo por deficiência de 5 alfa-reductase


Assuntos
Adolescente , Adulto , Humanos , Masculino , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/deficiência , Transtornos do Desenvolvimento Sexual/etiologia , Ginecomastia/complicações
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