Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
1.
Chem Res Toxicol ; 35(5): 782-791, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35417138

RESUMO

Tobacco-specific nitrosamine (TSNA) formation occurred during aerosol generation from select commercial cig-a-like e-cigarette products. To understand the drivers behind the potential formation of TSNAs in electronic cigarette (e-cigarette) aerosols and e-liquids, model e-liquid systems were generated in the lab to demonstrate that nitrite can react with nicotine and minor alkaloids to form TSNAs in e-liquids. In the presence of nitrite and nicotine, TSNA levels in e-liquids increased over time and the process was accelerated by elevated temperature. Additionally, TSNAs formed during aerosol generation when nitrite was present in the corresponding e-liquids. The commercial e-cigarette products that showed higher levels and formation of TSNAs were observed to contain nitrite and minor alkaloid impurities in the corresponding e-liquids. This study provides valuable information about drivers for TSNA formation in e-liquids and e-cigarette aerosols that may be applied to the evaluation and quality assurance of e-cigarette products.


Assuntos
Alcaloides , Sistemas Eletrônicos de Liberação de Nicotina , Nitrosaminas , Aerossóis , Nicotina , Nitritos , Nicotiana
2.
Front Chem ; 9: 742854, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660534

RESUMO

The Premarket Tobacco Product Applications (PMTA) guidance issued by the Food and Drug Administration for electronic nicotine delivery systems (ENDSs) recommends that in addition to reporting harmful and potentially harmful constituents (HPHCs), manufacturers should evaluate these products for other chemicals that could form during use and over time. Although e-vapor product aerosols are considerably less complex than mainstream smoke from cigarettes and heated tobacco product (HTP) aerosols, there are challenges with performing a comprehensive chemical characterization. Some of these challenges include the complexity of the e-liquid chemical compositions, the variety of flavors used, and the aerosol collection efficiency of volatile and semi-volatile compounds generated from aerosols. In this study, a non-targeted analysis method was developed using gas chromatography-mass spectrometry (GC-MS) that allows evaluation of volatile and semi-volatile compounds in e-liquids and aerosols of e-vapor products. The method employed an automated data analysis workflow using Agilent MassHunter Unknowns Analysis software for mass spectral deconvolution, peak detection, and library searching and reporting. The automated process ensured data integrity and consistency of compound identification with >99% of known compounds being identified using an in-house custom mass spectral library. The custom library was created to aid in compound identifications and includes over 1,100 unique mass spectral entries, of which 600 have been confirmed from reference standard comparisons. The method validation included accuracy, precision, repeatability, limit of detection (LOD), and selectivity. The validation also demonstrated that this semi-quantitative method provides estimated concentrations with an accuracy ranging between 0.5- and 2.0-fold as compared to the actual values. The LOD threshold of 0.7 ppm was established based on instrument sensitivity and accuracy of the compounds identified. To demonstrate the application of this method, we share results from the comprehensive chemical profile of e-liquids and aerosols collected from a marketed e-vapor product. Applying the data processing workflow developed here, 46 compounds were detected in the e-liquid formulation and 55 compounds in the aerosol sample. More than 50% of compounds reported have been confirmed with reference standards. The profiling approach described in this publication is applicable to evaluating volatile and semi-volatile compounds in e-vapor products.

3.
Food Chem Toxicol ; 113: 236-240, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29408542

RESUMO

Dosimetry models can be used to predict the dose of inhaled material, but they require several parameters including particle size distribution. The reported particle size distributions for aerosols from electronic nicotine delivery system (ENDS) products vary widely and don't always identify a specific product. A low-flow cascade impactor was used to determine the particle size distribution [mass median aerodynamic diameter (MMAD); geometric standard deviation (GSD)] from 20 different cartridge based ENDS products. To assess losses and vapor phase amount, collection efficiency of the system was measured by comparing the collected mass in the impactor to the difference in ENDS product mass. The levels of nicotine, glycerin, propylene glycol, water, and menthol in the formulations of each product were also measured. Regardless of the ENDS product formulation, the MMAD of all tested products was similar and ranged from 0.9 to 1.2 µm with a GSD ranging from 1.7 to 2.2. There was no consistent pattern of change in the MMAD and GSD as a function of number of puffs (cartridge life). The collection efficiency indicated that 9%-26% of the generated mass was deposited in the collection system or was in the vapor phase. The particle size distribution data are suitable for use in aerosol dosimetry programs.


Assuntos
Nicotina/administração & dosagem , Tamanho da Partícula , Sistemas Eletrônicos de Liberação de Nicotina , Glicerol/análise , Mentol/análise , Nicotina/análise , Propilenoglicol/análise , Água/análise
4.
Psychiatr Serv ; 67(6): 636-41, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-26876655

RESUMO

OBJECTIVE: The aim of this analysis was to determine changes in patterns of depression screening and diagnosis over three years in primary and specialty mental health care in a large health maintenance organization (HMO) as part of a project to develop quality measures for adolescent depression treatment. METHODS: Two series of aggregate data (2010-2012) were gathered from the electronic health records of the HMO for 44,342 unique adolescents (ages 12 to 21) who had visits in primary and mental health care. Chi square tests assessed the significance of changes in frequency and departmental location of Patient Health Questionnaire-9 (PHQ-9) administration, incidence of depression symptoms, and depression diagnoses. RESULTS: There was a significant increase in PHQ-9 use, predominantly in primary care, consistent with internally generated organizational recommendations to increase screening with the PHQ-9. The increase in PHQ-9 use led to an increase in depression diagnoses in primary care and a shift in the location of some diagnoses from specialty mental health care to primary care. The increase in PHQ-9 use was also linked to a decrease in the proportion of positive PHQ-9 results that led to formal depression diagnoses. CONCLUSIONS: The rate of depression screening in primary care increased over the study period. This increase corresponded to an increase in the number of depression diagnoses made in primary care and a shift in the location in which depression diagnoses were made, from the mental health department to primary care. The frequency of positive PHQ-9 administrations not associated with depression diagnoses also increased.


Assuntos
Depressão/diagnóstico , Depressão/epidemiologia , Sistemas Pré-Pagos de Saúde/estatística & dados numéricos , Adolescente , Criança , Registros Eletrônicos de Saúde , Feminino , Humanos , Masculino , Programas de Rastreamento/métodos , Escalas de Graduação Psiquiátrica , Autorrelato , Estados Unidos , Adulto Jovem
5.
Pediatr Pulmonol ; 50(4): 363-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24616279

RESUMO

OBJECTIVE: We tested the hypothesis that Respiratory Severity Score (RSS) on day of life 30 is predictive of mortality and length of mechanical ventilation in premature infants on prolonged mechanical ventilation. METHODS: A retrospective chart review was performed using the Nationwide Children's Hospital medical record and Vermont-Oxford Network databases. The primary outcome variable was survival to hospital discharge and the secondary outcome was length of mechanical ventilation after day of life 30. RESULTS: We identified 199 neonates admitted to Nationwide Children's Hospital between 2004 and 2007 with birth weight less than 1,500 g that received prolonged mechanical ventilation in the first 30 days of their life. A total of 184 infants were included in the analysis, excluding 14 patients with congenital anomalies and one infant with incomplete data. RSS on day of life 30 was significantly greater in the group of infants that died compared to those that survived (P = 0.003, 95% CI = [0.08, 0.40]). Further analysis demonstrated that the maximum difference in mortality was obtained with a threshold RSS of 6. Of the 109 patients who had RSS less than 6 on day of life 30, mortality rate was 4.6% (5/109) while those greater than or equal to 6 had a mortality rate of 21.3% (16/75). Both Kaplan-Meier survival curves comparing mortality and length of mechanical ventilation in infants with RSS < 6 versus those with RSS ≥ 6 demonstrated strong associations between RSS on day of life 30 and survival (P = 0.002) and length of ventilation after day of life 30 (P < 0.001). CONCLUSION: RSS ≥ 6 on day of life 30 is associated with higher mortality and longer period of mechanical ventilation in premature infants requiring mechanical ventilation through 30 days of life.


Assuntos
Displasia Broncopulmonar/mortalidade , Respiração Artificial/estatística & dados numéricos , Índice de Gravidade de Doença , Displasia Broncopulmonar/terapia , Feminino , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido de muito Baixo Peso , Unidades de Terapia Intensiva Neonatal , Masculino , Ohio/epidemiologia , Estudos Retrospectivos , Fatores de Tempo
6.
Ground Water ; 53 Suppl 1: 71-80, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24372403

RESUMO

In this study, we use PFLOTRAN, a highly scalable, parallel, flow, and reactive transport code to simulate the concentrations of 3H, 3He, CFC-11, CFC-12, CFC-113, SF6, 39Ar, and the mean groundwater age in heterogeneous fields on grids with an excess of 10 million nodes. We utilize this computational platform to simulate the concentration of multiple tracers in high-resolution, heterogeneous 2D and 3D domains, and calculate tracer-derived ages. Tracer-derived ages show systematic biases toward younger ages when the groundwater age distribution contains water older than the maximum tracer age. The deviation of the tracer-derived age distribution from the true groundwater age distribution increases with increasing heterogeneity of the system. However, the effect of heterogeneity is diminished as the mean travel time gets closer to the tracer age limit. Age distributions in 3D domains differ significantly from 2D domains. 3D simulations show decreased mean age, and less variance in age distribution for identical heterogeneity statistics. High-performance computing allows for investigation of tracer and groundwater age systematics in high-resolution domains, providing a platform for understanding and utilizing environmental tracer and groundwater age information in heterogeneous 3D systems.


Assuntos
Monitoramento Ambiental/métodos , Água Subterrânea/química , Argônio/análise , Clorofluorcarbonetos/análise , Simulação por Computador , Hélio/análise , Hidrogênio/análise , Radioisótopos , Hexafluoreto de Enxofre/análise , Movimentos da Água
7.
Soc Sci Med ; 75(7): 1263-70, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22726619

RESUMO

Lifetime health disparity between African-American and white females begins with lower birthweight and higher rates of childhood overweight. In adolescence, African-American girls experience earlier menarche. Understanding the origins of these health disparities is a national priority. There is growing literature suggesting that the life course health development model is a useful framework for studying disparities. The purpose of this study was to quantify the influence of explanatory factors from key developmental stages on the age of menarche and to determine how much of the overall race difference in age of menarche they could explain. The factors were maternal age of menarche, birthweight, poverty during early childhood (age 0 through 5 years), and child BMI z-scores at 6 years. The sample, drawn from the US National Longitudinal Surveys of Youth Child-Mother file, consisted of 2337 girls born between 1978 and 1998. Mean age of menarche in months was 144 for African-American girls and 150 for whites. An instrumental variable approach was used to estimate a causal effect of child BMI z-score on age of menarche. The instrumental variables were pre-pregnancy BMI, high gestational weight gain and smoking during pregnancy. We found strong effects of maternal age of menarche, birthweight, and child BMI z-score (-5.23, 95% CI [-7.35,-3.12]) for both African-Americans and whites. Age of menarche declined with increases in exposure to poverty during early childhood for whites. There was no effect of poverty for African-Americans. We used Oaxaca decomposition techniques to determine how much of the overall race difference in age of menarche was attributable to race differences in observable factors and how much was due to race dependent responses. The African-American/white difference in childhood BMI explained about 18% of the overall difference in age of menarche and birthweight differences explained another 11%.


Assuntos
Negro ou Afro-Americano/estatística & dados numéricos , Menarca/etnologia , População Branca/estatística & dados numéricos , Adolescente , Distribuição por Idade , Peso ao Nascer , Índice de Massa Corporal , Criança , Feminino , Humanos , Estudos Longitudinais , Pobreza , Estados Unidos
8.
J Chromatogr Sci ; 48(1): 12-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20056029

RESUMO

A method to quantify eight carbonyl compounds in mainstream cigarette smoke is presented using ultra-high pressure liquid chromatography (UHPLC). The combination of UHPLC and mass spectrometry (UHPLC-MS) dramatically reduces analysis times as compared to the current in-house high-performance liquid chromatography (HPLC)-UV method. In addition, improved detector selectivity and peak resolution are observed. Sample analysis times are reduced from 47 min with HPLC-UV to less than 5 min using this improved method. Atmospheric pressure chemical ionization, atmospheric pressure photo ionization, and electrospray ionization are directly compared to evaluate ionization potential and linear response range for the carbonyl 2,4-dinitrophenylhydrazine derivatives. Smoke extracts from three standard smoking protocols are analyzed by both UHPLC-MS and HPLC-UV for method comparison purposes.

10.
Child Abuse Negl ; 32(8): 811-8, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18667237

RESUMO

OBJECTIVE: To examine the association between physical domestic violence victimization (both recent and more than a year in past measured by self-report) and self-reported disciplinary practices among female parents/caregivers in a national sample of families referred to child welfare. METHODS: Cross-sectional survey of more than 3,000 female caregivers in the National Survey of Child and Adolescent Well-being (NSCAW) study, a nationally representative sample of children and their families referred to child welfare agencies for investigation of abuse and neglect. Women reported physical domestic violence victimization and their disciplinary practices for their child on different versions of the Conflict Tactics Scales. RESULTS: Four hundred and forty-three women reported prior year domestic violence, 1,161 reported domestic violence but not in the past 12 months, and 2,025 reported no domestic violence exposure. Any prior domestic violence exposure was associated with higher rates of self-reported psychological aggression, physical aggression and neglectful disciplinary behaviors as compared to those with no domestic violence victimization in bivariate comparisons. After controlling for child behavior, demographic factors, and maternal characteristics, those with remote and recent domestic violence victimization employed more self-reported psychological aggression, while only caregivers with recent DV reported more physical aggression or neglectful behaviors. CONCLUSIONS: In a national child welfare sample, self-reported aggressive and neglectful parenting behaviors were common. In this sample, domestic violence victimization is associated with more self-reported aggressive and neglectful disciplinary behaviors among female caregivers. The mechanism for these associations is not clear. PRACTICE IMPLICATIONS: Rates of aggressive and neglectful disciplinary practices are especially high among female parents/caregivers exposed to domestic violence. Child welfare agencies should plan routine and structured assessments for domestic violence among parents/caregivers and implement parenting interventions to reduce harmful disciplinary practices for those families identified.


Assuntos
Agressão/psicologia , Proteção da Criança/estatística & dados numéricos , Vítimas de Crime/psicologia , Violência Doméstica/psicologia , Poder Familiar/psicologia , Punição/psicologia , Adolescente , Mulheres Maltratadas/psicologia , Mulheres Maltratadas/estatística & dados numéricos , Controle Comportamental , Criança , Maus-Tratos Infantis/psicologia , Maus-Tratos Infantis/estatística & dados numéricos , Transtornos do Comportamento Infantil/psicologia , Filho de Pais com Deficiência/psicologia , Filho de Pais com Deficiência/estatística & dados numéricos , Vítimas de Crime/estatística & dados numéricos , Estudos Transversais , Violência Doméstica/estatística & dados numéricos , Feminino , Humanos , Meio Social , Fatores Socioeconômicos , Maus-Tratos Conjugais/psicologia , Maus-Tratos Conjugais/estatística & dados numéricos , Violência/psicologia , Violência/estatística & dados numéricos
11.
J Adolesc Health ; 40(1): 84.e1-7, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17185210

RESUMO

PURPOSE: One of the risk factors for poor adult health may be adolescent antisocial behavior, especially in girls. This study was conducted to determine if negative young adult health outcomes in girls who previously had adolescent antisocial behavior could be explained by demographic factors and pre-existing health problems. METHODS: This 3-year longitudinal study recruited 93 girls, ages 15-17 years (52 with conduct disorder [CD]; 41 with no psychiatric illness [normal controls; NC]) from the community. Baseline interviews of girls and parents collected demographic, psychiatric, and medical history data. Three annual interviews collected data about medical problems, health care service utilization, and reproductive health. In addition, the final follow-up included a standardized self-report questionnaire about young adult health status. RESULTS: CD and NC groups did not differ in age, racial composition, social class, proportion of smokers, or drug and alcohol experimentation. They were qualitatively different in baseline medical histories. Controlling for age at follow-up and baseline medical problems, the CD group as young adults had worse overall health, more discomfort, higher rates of unhealthy habits, lower rates of healthy behaviors, and more pregnancies at earlier ages. There were no group differences in rates of disorders, injuries, or health care usage. CONCLUSIONS: Adolescent girls with CD as young adults have poorer overall health, more discomfort, more health risk behaviors, and earlier onset of adult reproductive behaviors, even when controlling for demographic factors and pre-existing health history. Clinical and research implications are discussed.


Assuntos
Transtorno da Conduta/epidemiologia , Nível de Saúde , Adolescente , Adulto , Estudos de Casos e Controles , Transtorno da Conduta/psicologia , Feminino , Seguimentos , Humanos , Modelos de Riscos Proporcionais , Risco , Estados Unidos/epidemiologia
12.
Curr Opin Pediatr ; 18(6): 649-53, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17099365

RESUMO

PURPOSE OF REVIEW: Pediatric mental disorders are among the most common disorders of childhood and are routinely seen in primary care. We review innovative management strategies, treatment technologies, and models of collaboration with behavioral health specialists in general medical settings. Our goal is to advance the integration of behavioral health services into primary care. RECENT FINDINGS: The application of mental health interventions with proven efficacy holds great promise for youths with mental disorders. Unfortunately, traditional primary-care management of pediatric mental disorders is characterized by nonspecific counseling, low-dose prescribing, and referrals to specialty settings that are often not completed. SUMMARY: The development, study, and refinement of new assessment and treatment technologies, supplemental treatments, and collaborative models of care delivery will be necessary to ensure more effective care for youths with mental disorders and their families. The promise of pediatric mental healthcare will not be fulfilled unless primary-care clinicians and behavioral health specialists forge new collaborative relationships that enhance the delivery of evidence-based care to affected children and their families.


Assuntos
Transtornos Mentais/terapia , Serviços de Saúde Mental/tendências , Equipe de Assistência ao Paciente , Pediatria/métodos , Atenção Primária à Saúde , Adolescente , Criança , Pré-Escolar , Humanos , Transtornos Mentais/diagnóstico , Atenção Primária à Saúde/métodos , Encaminhamento e Consulta
13.
J Interpers Violence ; 20(5): 632-46, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15788558

RESUMO

To address several key questions in social science research, repeated interviews of individuals drawn from difficult populations are required. This article describes an approach for addressing the challenges associated with longitudinal interview studies, including locating research participants, obtaining reliable and valid interview data over time, and retaining participants across the course of the study. We applied this approach to conduct a study designed to identify changeable risk factors for violence among high-risk people with mental illness. To successfully conduct weekly interviews of these individuals in the community across a 6-month period, we developed a flexible and personalized interview format; carefully selected, trained, and supervised staff; and developed incentives to maximize participant retention. Each of these three steps is discussed as a guide for future longitudinal studies that involve interviewing difficult populations.


Assuntos
Transtorno da Personalidade Antissocial/prevenção & controle , Centros Comunitários de Saúde Mental/normas , Entrevistas como Assunto/normas , Assunção de Riscos , Inquéritos e Questionários/normas , Violência/prevenção & controle , Adulto , Agressão/psicologia , Humanos , Estudos Longitudinais , Fatores de Risco , Fatores de Tempo , Estados Unidos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA