VILMA LEYTON
Projetos de Pesquisa
Unidades Organizacionais
Departamento de MedicinaLegal, Ética Médica e Medicina Social e do Trabalho, Faculdade de Medicina - Docente
LIM/40 - Laboratório de Imunohematologia e Hematologia Forense, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/40 - Laboratório de Imunohematologia e Hematologia Forense, Hospital das Clínicas, Faculdade de Medicina - Líder
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- Determination of antidepressants in whole blood using hollow-fiber liquid-phase microextraction and gas chromatography-mass spectrometry(2014) SANTOS, Marcelo Filonzi dos; FERRI, Caio Caleiras; SEULIN, Saskia Carolina; LEYTON, Vilma; PASQUALUCCI, Carlos Augusto Goncalves; MUNOZ, Daniel Romero; YONAMINE, MauricioA hollow-fiber liquid-phase microextraction (HF-LPME), used in three-phase mode, and combined with gas chromatography-mass spectrometry (GC-MS), was developed to quantify antidepressants and their major metabolites (amitriptyline, nortriptyline, imipramine, desipramine, clomipramine, desmethylclomipramine, fluoxetine, and norfluoxetine) in whole blood samples, using their deuterated analogs as internal standards. The HF-LPME system comprised a disposable 8-cm polypropylene porous hollow fiber, 4.0 ml of sample solution (0.5 ml of blood added to 3.5 ml of 0.1 M NaOH: donor phase), dodecane (organic phase), and 0.1 M formic acid (acceptor phase) for extraction. After stirring the system, the acceptor phase was evaporated under a nitrogen stream and resuspended in 30 mu l of methanol. Derivatization was not required. A 2.0-mu l aliquot of this solution was injected into a GC-MS system. The method was validated after the optimization of several parameters that may influence the extraction efficiency. The limits of quantification for all antidepressants were below the therapeutic levels (20.0 ng/ml). The average intraday and interday precisions were within 9.7 and 9.8 %, respectively, for all analytes. The calibration curves were linear in the concentration range of 20-1,200 ng/ml. The developed method was applied to seven actual postmortem samples. Tricyclic antidepressants were detected in all of the analyzed cases. To our knowledge, this is the first demonstration of usefulness of HF-LPME for analysis of antidepressants in postmortem forensic cases.
bookPart Toxicologia Forense(2020) LEYTON, Vilma; MAGALHãES, Juliana Gallottini de; PONCE, Júlio de Carvalho- Alcohol and drug involvement in motorcycle driver injuries in the city of Sao Paulo, Brazil: Analysis of crash culpability and other associated factors(2016) CARVALHO, Heraclito Barbosa de; ANDREUCCETTI, Gabriel; REZENDE, Marcelo Rosa; BERNINI, Celso; SILVA, Jorge Santos; LEYTON, Vilma; GREVE, Julia Maria D'AndreaBackground: Earlier studies have already identified that a greater proportion of injured drivers are under the effects of illicit drugs than alcohol in Brazil, but the crash risk attributable to each substance is still unknown. Methods: Injured motorcycle drivers who were involved in traffic accidents in the West Zone of the city of Sao Paulo were recruited for a cross-sectional study based on crash culpability analysis. Alcohol and drug positivity among drivers was evaluated according to their responsibility for the crash. Culpability ratios were generated based on the proportion of drivers who were deemed culpable in relation to those considered not culpable according to the use of drugs and alcohol. Results: Of the 273 drivers recruited, 10.6% tested positive for alcohol. Among those who were also tested for drugs (n=232), 20.3% had consumed either alcohol and/or other drugs, 15.5% of whom were positive only for drugs other than alcohol, specifically cannabis and cocaine. Drivers who tested positive for alcohol were significantly less likely to possess a valid driver's license and to report driving professionally, whereas those who had consumed only drugs were more likely to drive professionally. The culpability ratio estimated for alcohol-positive drivers was three times higher than that for alcohol-free drivers, showing a superior ratio than drivers who had consumed only drugs other than alcohol, who presented a 1.7 times higher culpability ratio than drug-free drivers. Conclusion: Substance use was overrepresented among culpable motorcycle drivers, with alcohol showing a greater contribution to crash culpability than other drugs.
- Determination of cocaine and its derivatives in hair samples by liquid phase microextraction (LPME) and gas chromatography-mass spectrometry (GC-MS)(2017) PEGO, A. M. F.; ROVERI, F. L.; KUNINARI, R. Y.; LEYTON, V.; MIZIARA, I. D.; YONAMINE, M.Hair testing is a recognized approach when it comes to accessing historical drug use. According to the World Drug Report of United Nations Office on Drugs and Crime (UNODC) 2015, Brazil is the largest cocaine (COC) market in South America. New analytical methodologies to detect crack/cocaine analytes in hair samples are highly desirable. Here, a method consisting of a liquid-phase microextraction (LPME) as a clean-up step, followed by gas chromatography-mass spectrometry (GC-MS) analysis has been proposed. The new validated method consisted of a washing step; an overnight incubation with methanol and a quick derivatization with butylchloroformate. Once derivatized, the samples were then submitted to the LPME procedure. Limits of detection (LoD) and quantitation (LoQ) obtained were of 0.1 and 0.5 ng/ mg for COC 0.4 and 0.5 ng/mg for anhydroecgonine methyl ester (AEME); 0.03 and 0.05 for cocaethylene (CE), respectively and 0.05 ng/mg for both LoD and LoQ for benzoylecgonine (BZE). All calibration curves were linear over the scope applied, from LoQ up to 20 ng/mg, with a r(2) > 0.99. Precision and accuracy assays showed acceptable % RSD values, according to international guidelines. Twelve postmortem head hair samples stemming from the Institute of Legal Medicine of Sao Paulo (IML-SP) have been analyzed, from which seven have shown to be positive for COC (0.75-> 20 ng/mg) and BZE (0.1-> 20 ng/mg). Apart from COC's main metabolite, four samples were also positive for CE (0.1-3.9 ng/mg) and three samples for AEME (0.5-4.9 ng/mg). To conclude, the LPME technique together with GC-MS analysis have shown promising results and were able to meet the demand of the laboratory of analyzing postmortem hair samples to look for all four analytes.
- Alcohol Consumption and Violent Deaths in the City of Sao Paulo in 2015(2020) GONCALVES, Raphael Eduardo Marques; PONCE, Julio de Carvalho; LEYTON, VilmaBackground: Excessive alcohol consumption is a serious public health issue, because drunkenness affects critical judgment and self-control, making people more vulnerable to violence and accidents, with thus a potential association between alcohol consumption and violent deaths.Objective: To assess the association between alcohol consumption and violent deaths in the city of Sao Paulo, Brazil, in 2015, and its relationship with gender, age, cause of death and blood alcohol concentration (BAC) of victims.Methods: A cross-sectional retrospective study was conducted by collection of data from 2,882 victims of violent deaths subjected to examination of BAC from the archives of the Institute of Legal Medicine of the State of Sao Paulo, Brazil.Results: Alcohol was detected in blood samples of 27.06% of the victims and mean BAC levels were 1.92 +/- 1.24 g/L. The mean age of the victims was 33.49 +/- 15.19 years. The majority of the victims were male (84.14%) and the prevalence of positive BAC was higher amongst men (28.74%) than women (18.16%). Homicide was the most prevalent cause of death in the sample (36.57%), but there were a higher proportion of traffic accidents victims with positive BAC (32.01%), as well as higher BAC levels in these victims (46.77% in the range of 1.6-2.5 g/L).Conclusions: The results obtained in this study support a potential association between alcohol consumption and violent deaths in the city of Sao Paulo, mainly in traffic accidents victims.
- Use of Alcohol Mixed with Energy Drinks Increases the Prevalence of Driving Violations among Brazilian Truck Drivers(2020) OLIVEIRA, Lucio Garcia de; ECKSCHMIDT, Frederico; LEYTON, Vilma; CARVALHO, Heraclito Barbosa deBackground: The use of alcohol mixed with energy drinks (AmED) has been reported to be associated with a variety of unsafe driving practices. Truck drivers are vulnerable to driving violations, particularly because of their engagement in drug use. The use of AmED among these professionals remains unknown. Aim: To estimate the prevalence of AmED use and its association with driving violations among truck drivers. Methods: 684 drivers were recruited in Sao Paulo, Brazil. The use of drugs was reported. Drivers were split into three groups: (a) alcohol abstainers (AA); (b) alcohol-only users (AO); and (c) users of AmED. Intergroup comparisons were performed by polynomial logistic regression (the reference category was AO). We also performed Poisson regression analysis to obtain the prevalence ratio; the significance level was stipulated at 5%. Results: The prevalence of drivers reporting the use of AmED was 16.8%. Users of AmED (a) were younger, (b) were less experienced drivers, (c) had a heavier pattern of alcohol use, (d) used illicit drugs more frequently, and (e) had poorer sleep quality than AO subjects. A higher prevalence of drivers who had arguments or fights while driving (PR = 1.71) and of drivers who drove unbelted (PR = 1.66) ingested AmED than of AO subjects. Conclusions/importance: The use of AmED increased the prevalence of driving violations beyond the risks commonly attributed to alcohol use. We suggest additional investments in preventative measures based on the beverage category and a revision of the work organization of truck drivers to reduce their health and social risks.
- Alcohol use by suicide victims in the city of Sao Paulo, Brazil, 2011-2015(2018) GONCALVES, Raphael Eduardo Marques; PONCE, Julio de Carvalho; LEYTON, VilmaExcessive alcohol consumption is a serious public health issue, because drunkenness affects critical judgment and self-control which could trigger violent and self-harm behavior, with thus a potential association between alcohol consumption and suicide deaths. The objective of the present study was to assess the association between alcohol consumption and suicide deaths in the city of Sao Paulo, Brazil, from 2011 to 2015, and its relationship with socio-demographic characteristics of the victims and the circumstances of the suicide. A cross-sectional retrospective study was conducted by collection of data from 1,700 suicide victims subjected to examination of blood alcohol concentration (BAC) from toxicology reports from the Institute of Legal Medicine of the State of Sao Paulo, Brazil. Alcohol was detected in blood samples of 30.2% of the victims and mean BAC levels were 1.73 +/- 0.08 g/L. The mean age of the victims was 39.90 +/- 0.75 years. The majority of the victims were male (74.6%) and the prevalence of positive BAC was higher amongst men (34.7%) than women (17.1%), p < 0.05. The majority of the victims were white skinned (64.7%), but there was a higher proportion of victims with positive BAC among mulatto and black individuals, p < 0.05. Hanging was the most prevalent suicide method in the sample (48.7%) and amongst men (55.4%), but amongst women it was jumping from a height (35%), p < 0.05.
- Alcohol use among fatally injured victims in SAo Paulo, Brazil: bridging the gap between research and health services in developing countries(2017) ANDREUCCETTI, Gabriel; LEYTON, Vilma; LEMOS, Nikolas P.; MIZIARA, Ivan Dieb; YE, Yu; TAKITANE, Juliana; MUNOZ, Daniel Romero; REINGOLD, Arthur L.; CHERPITEL, Cheryl J.; CARVALHO, Heraclito Barbosa deBackground and aimsMost studies reporting alcohol use among fatally injured victims are subject to bias, particularly those related to sample selection and to absence of injury context data. We developed a research method to estimate the prevalence of alcohol consumption and test correlates of alcohol use prior to fatal injuries. Design, Setting and ParticipantsCross-sectional study based on a probability sample of fatally injured adult victims (n=365) autopsied in SAo Paulo, Brazil. Victims were sampled within systematically selected 8-hour sampling blocks, generating a representative sample of fatal injuries occurring during all hours of the day for each day of the week between June 2014 and December 2015. MeasurementsThe presence of alcohol and blood alcohol concentration (BAC) were the primary outcomes evaluated according to victims' socio-demographic, injury context data (type, day, time and injury place) and criminal history characteristics. FindingsAlcohol was detected in 30.1% [95% confidence interval (CI)=25.6-35.1)] of the victims, with a mean blood alcohol level (BAC) level of 0.11%w/v (95% CI=0.09-0.13) among alcohol-positive cases. Black and mixed race victims presented a higher mean BAC than white victims (P=0.03). Fewer than one in every six suicides tested positive for alcohol, while almost half of traffic-related casualties were alcohol-positive. Having suffered traffic-related injuries, particularly those involving vehicle crashes, and injuries occurring during weekends and at night were associated significantly with alcohol use before injury (P<0.05). ConclusionsNearly one-third of fatal injuries in SAo Paulo between June 2014 and December 2015 were alcohol-related, with traffic accidents showing a greater association with alcohol use than other injuries. The sampling methodology tested here, including the possibility of adding injury context data to improve population-based estimates of alcohol use before fatal injury, appears to be a reliable and lower-cost strategy for avoiding biases common in death investigations.
- Amphetamine, cocaine and cannabinoids use among truck drivers on the roads in the State of Sao Paulo, Brazil(2012) LEYTON, V.; SINAGAWA, D. M.; OLIVEIRA, K. C. B. G.; SCHMITZ, W.; ANDREUCCETTI, G.; MARTINIS, B. S. De; YONAMINE, M.; MUNOZ, D. R.Drugs are important risk factors for traffic accidents. In Brazil, truck drivers report using amphetamines to maintain their extensive work schedule and stay awake. These drugs can be obtained without prescription easily on Brazilian roads. The use of these stimulants can result in health problems and can be associated with traffic accidents. There are Brazilian studies that show that drivers use drugs. However, these studies are questionnaire-based and do not always reflect real-life situations. The purpose of this study was to demonstrate the prevalence of drug use by truck drivers on the roads of Sao Paulo State, Brazil, during 2009. Drivers of large trucks were randomly stopped by police officers on the interstate roads during morning hours. After being informed of the goals of the study, the drivers gave written informed consent before providing a urine sample. In addition, a questionnaire concerning sociodemographic characteristics and health information was administered. Urine samples were screened for amphetamines, cocaine, and cannabinoids by immunoassay and the confirmation was performed using gas chromatography-mass spectrometry (GC-MS). Of the 488 drivers stopped, 456 (93.4%) provided urine samples, and 9.3% of them (n = 42) tested positive for drugs. Amphetamines were the most commonly found (n = 26) drug, representing 61.9% of the positive samples. Ten cases tested positive for cocaine (23.8%), and five for cannabinoids (11.9%). All drivers were male with a mean age of 40 +/- 10.8 years, and 29.3% of them reported some health problem (diabetes, high blood pressure and/or stress). A high incidence of truck drivers who tested positive for drug use was found, among other reported health problems. Thus, there is an evident need to promote a healthier lifestyle among professional drivers and a need for preventive measures aimed at controlling the use of drugs by truck drivers in Brazil.
- Prevalence of drugs in oral fluid from truck drivers in Brazilian highways(2017) BOMBANA, Henrique Silva; GJERDE, Hallvard; SANTOS, Marcelo Filonzi dos; JAMT, Ragnhild Elen Gjulem; YONAMINE, Mauricio; ROHLFS, Waldo Jose Caram; MUNOZ, Daniel Romero; LEYTON, VilmaTraffic accidents are responsible for 1.25 million deaths worldwide and are the most common cause of death among those aged 15-29 years. In Brazil, traffic accidents caused more than 44,000 deaths in 2014. The use of psychoactive drugs is an important risk factor for being involved in traffic accidents. Previous studies have found that psychoactive substances are commonly used by truck drivers in Brazil to maintain their extensive work schedule and stay awake while driving during nighttime hours. The state of Sao Paulo is one of the most important states regarding goods transportation. Important highways cross through Sao Paulo to other regions from Brazil and to other countries in Latin America. This study aims to determine the prevalence of illicit drug use by truck drivers in the state of Sao Paulo through toxicological analyses of oral fluid. Truck drivers were randomly stopped by police officers on federal roads during morning hours. Oral fluid samples were collected using the Quantisal (TM) device. In addition, a questionnaire concerning sociodemographic characteristics and health information was administered. Oral fluid samples were screened for amphetamine, cocaine, and tetrahydrocannabinol (Delta 9-THC) by ELISA and the confirmation was performed using ultra performance liquid chromatography with tandem mass spectrometry detection (UPLC-MS/MS). Of the 764 drivers stopped, 762 agreed to participate. The participants were driving an average of 614 km and 9.4 h a day. Of the total samples, 5.2% (n = 40) tested positive for drugs. Cocaine was the most frequently found drug (n = 21), followed by amphetamine (n = 16) and D9-THC (n = 8). All drivers were men with an average age of 42.5 years. With these results we were able to verify that many truck drivers were still consuming psychoactive drugs while driving, and cocaine was the most prevalent one. This reinforces the need for preventive measures aimed at controlling the use of illicit drugs by truck drivers in Brazil.