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1.
Prev Med ; 165(Pt B): 107213, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35995103

RESUMEN

The reinforcing characteristics of e-cigarettes could moderate the impact of reducing cigarette nicotine content. In this study, people who smoke daily were recruited from North Carolina and Pennsylvania (US) in 2018 and 2019. Within a randomized 2 × 2 × 2 factorial design, participants received investigational cigarettes and an e-cigarette for 12 weeks. Cigarette nicotine content was very low (0.4 mg/g of tobacco; VLNC) or normal (15.8 mg/g; NNC). E-liquids were 0.3% ("low") or 1.8% ("moderate") freebase nicotine, and available in tobacco flavors or tobacco, fruit, dessert and mint flavors. Study recruitment concluded before reaching the planned sample size (N = 480). Fifty participants were randomized and 32 completed the study. We found that randomization to VLNC, relative to NNC cigarettes, reduced self-reported cigarettes per day (CPD; mean difference: -12.96; 95% CI: -21.51, -4.41; p = 0.005); whereas e-liquid nicotine content and flavor availability did not have significant effects. The effect of cigarette nicotine content was larger in the moderate vs. low nicotine e-liquid groups and in the all flavors versus tobacco flavors e-liquid groups; tests of the interaction between e-liquid characteristics and cigarette nicotine content were not significant. Biomarkers of smoke exposure at Week 12 did not differ across conditions, which may reflect variability in adherence to only using VLNC cigarettes. In conclusion this study offers preliminary evidence that the extent to which cigarette nicotine reduction decreases smoking may depend on the reinforcing characteristics of alternative products, including the available nicotine contents and flavors of e-cigarettes.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Productos de Tabaco , Humanos , Nicotina , Uso de Tabaco , Biomarcadores
2.
Carcinogenesis ; 42(5): 772-783, 2021 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-33710266

RESUMEN

Prostate cancer (PCa) constitutes a serious health challenge and remains one of the main causes of cancer-related death among men. The more aggressive form of the disease has been attributed to androgen independence, resulting in a lack of response to androgen deprivation therapy and sustained activation of other growth pathways. The scaffold proteins ß-arrestin 1 and 2 (ßarr1 and ßarr2), which are known to mediate G protein-coupled receptor desensitization and internalization, were also shown to modulate prostate tumorigenesis. ßarr1 is significantly overexpressed (>4-fold) in PCa cells relative to ßarr2. In this study, we investigated the effect of ßarr1 overexpression in PCa development and progression using the mouse and human PCa cell xenografts, and autochthonous transgenic adenocarcinoma of the mouse prostate (TRAMP) models deficient in ß-arrestin depletion of ßarr1 in TRAMP mice (TRAMP/ßarr1-/-) increased PCa growth and decreased overall survival relative to control TRAMP or TRAMP/ßarr2-/- animals. Prostate tissues from TRAMP/ßarr1-/- tumors displayed an increase in androgen receptor (AR) expression, whereas overexpression of ßarr1 in TRAMP-C1 (TRAMP-C1-ßarr1-GFP) which derived from TRAMP decreased AR expression, cell proliferation and tumor growth in nude mice xenografts, relative to control TRAMP-C1-GFP. Knockdown of ßarr1 expression in human MDA PCa 2b cells (MDA PCa 2b-ßarr1-/-) also decreased AR expression cell proliferation and tumor growth relative to control (MDA PCa 2b-Sham) cells. Interestingly, both TRAMP-C1-ßarr1-GFP and MDA PCa 2b-ßarr1-/- xenografts showed a decrease in AKT phosphorylation but an increase in MAPK activation. Altogether, the data indicate that the effect of ßarr1 in modulating AR signaling to regulate PCa aggressiveness is cell and host autonomous.


Asunto(s)
Carcinogénesis/genética , Neoplasias de la Próstata/genética , Miembro 25 de Receptores de Factores de Necrosis Tumoral/genética , beta-Arrestina 1/genética , Arrestina beta 2/genética , Animales , Animales Modificados Genéticamente , Línea Celular Tumoral , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Xenoinjertos , Humanos , Masculino , Ratones , Neoplasias de la Próstata/patología , Receptores Androgénicos/genética , Transducción de Señal
3.
N Engl J Med ; 373(14): 1340-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26422724

RESUMEN

BACKGROUND: The Food and Drug Administration can set standards that reduce the nicotine content of cigarettes. METHODS: We conducted a double-blind, parallel, randomized clinical trial between June 2013 and July 2014 at 10 sites. Eligibility criteria included an age of 18 years or older, smoking of five or more cigarettes per day, and no current interest in quitting smoking. Participants were randomly assigned to smoke for 6 weeks either their usual brand of cigarettes or one of six types of investigational cigarettes, provided free. The investigational cigarettes had nicotine content ranging from 15.8 mg per gram of tobacco (typical of commercial brands) to 0.4 mg per gram. The primary outcome was the number of cigarettes smoked per day during week 6. RESULTS: A total of 840 participants underwent randomization, and 780 completed the 6-week study. During week 6, the average number of cigarettes smoked per day was lower for participants randomly assigned to cigarettes containing 2.4, 1.3, or 0.4 mg of nicotine per gram of tobacco (16.5, 16.3, and 14.9 cigarettes, respectively) than for participants randomly assigned to their usual brand or to cigarettes containing 15.8 mg per gram (22.2 and 21.3 cigarettes, respectively; P<0.001). Participants assigned to cigarettes with 5.2 mg per gram smoked an average of 20.8 cigarettes per day, which did not differ significantly from the average number among those who smoked control cigarettes. Cigarettes with lower nicotine content, as compared with control cigarettes, reduced exposure to and dependence on nicotine, as well as craving during abstinence from smoking, without significantly increasing the expired carbon monoxide level or total puff volume, suggesting minimal compensation. Adverse events were generally mild and similar among groups. CONCLUSIONS: In this 6-week study, reduced-nicotine cigarettes versus standard-nicotine cigarettes reduced nicotine exposure and dependence and the number of cigarettes smoked. (Funded by the National Institute on Drug Abuse and the Food and Drug Administration Center for Tobacco Products; ClinicalTrials.gov number, NCT01681875.).


Asunto(s)
Exposición por Inhalación/análisis , Nicotiana/química , Nicotina/normas , Productos de Tabaco/normas , Tabaquismo , Biomarcadores/orina , Creatinina/orina , Método Doble Ciego , Humanos , Modelos Lineales , Nicotina/administración & dosificación , Nicotina/efectos adversos , Síndrome de Abstinencia a Sustancias , Breas/análisis , Breas/normas , Productos de Tabaco/análisis , Tabaquismo/prevención & control , Estados Unidos , United States Food and Drug Administration
4.
JAMA ; 320(9): 880-891, 2018 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-30193275

RESUMEN

Importance: The optimal temporal approach for reducing nicotine to minimally or nonaddictive levels in all cigarettes sold in the United States has not been determined. Objectives: To determine the effects of immediate vs gradual reduction in nicotine content to very low levels and as compared with usual nicotine level cigarettes on biomarkers of toxicant exposure. Design, Setting, and Participants: A double-blind, randomized, parallel-design study with 2 weeks of baseline smoking and 20 weeks of intervention was conducted at 10 US sites. A volunteer sample of daily smokers with no intention to quit within 30 days was recruited between July 2014 and September 2016, with the last follow-up completed in March 2017. Interventions: (1) Immediate reduction to 0.4 mg of nicotine per gram of tobacco cigarettes; (2) gradual reduction from 15.5 mg to 0.4 mg of nicotine per gram of tobacco cigarettes with 5 monthly dose changes; or (3) maintenance on 15.5 mg of nicotine per gram of tobacco cigarettes. Main Outcomes and Measures: Between-group differences in 3 co-primary biomarkers of smoke toxicant exposure: breath carbon monoxide (CO), urine 3-hydroxypropylmercapturic acid (3-HPMA, metabolite of acrolein), and urine phenanthrene tetraol (PheT, indicator of polycyclic aromatic hydrocarbons) calculated as area under the concentration-time curve over the 20 weeks of intervention. Results: Among 1250 randomized participants (mean age, 45 years; 549 women [44%]; 958 [77%] completed the trial), significantly lower levels of exposure were observed in the immediate vs gradual reduction group for CO (mean difference, -4.06 parts per million [ppm] [95% CI, -4.89 to -3.23]; P < .0055), 3-HPMA (ratio of geometric means, 0.83 [95% CI, 0.77 to 0.88]; P < .0055), and PheT (ratio of geometric means, 0.88 [95% CI, 0.83 to 0.93]; P < .0055). Significantly lower levels of exposure were observed in the immediate reduction vs control group for CO (mean difference, -3.38 [95% CI, -4.40 to -2.36]; P < .0055), 3-HPMA (ratio of geometric means, 0.81 [95% CI, 0.75 to 0.88]; P < .0055), and PheT (ratio of geometric means, 0.86 [95% CI, 0.81 to 0.92]; P < .0055). No significant differences were observed between the gradual reduction vs control groups for CO (mean difference, 0.68 [95% CI, -0.31 to 1.67]; P = .18), 3-HPMA (ratio of geometric means, 0.98 [95% CI, 0.91 to 1.06]; P = .64), and PheT (ratio of geometric means, 0.98 [95% CI, 0.92 to 1.04]; P = .52). Conclusions and Relevance: Among smokers, immediate reduction of nicotine in cigarettes led to significantly greater decreases in biomarkers of smoke exposure across time compared with gradual reduction or a control group, with no significant differences between gradual reduction and control. Trial Registration: clinicaltrials.gov Identifier: NCT02139930.


Asunto(s)
Biomarcadores/análisis , Nicotina , Productos de Tabaco , Acetilcisteína/análogos & derivados , Acetilcisteína/orina , Adulto , Área Bajo la Curva , Biomarcadores/orina , Pruebas Respiratorias , Monóxido de Carbono/análisis , Creatinina/orina , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nicotina/efectos adversos , Nicotina/análisis , Fenantrenos/orina , Humo , Cese del Hábito de Fumar/estadística & datos numéricos , Síndrome de Abstinencia a Sustancias , Nicotiana , Productos de Tabaco/análisis , Tabaquismo
5.
Anal Bioanal Chem ; 399(5): 1823-33, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21181133

RESUMEN

In this study, electrical impedance-based measurements were used to distinguish oral cancer cells and non-cancer oral epithelial cells based on their cellular activities on the microelectrodes in a real-time and label-free manner. CAL 27 and Het-1A cell lines were used as the models of oral cancer cells and non-cancer oral epithelial cells, respectively. Various cellular activities, including cell adhesion, spreading, and proliferation were monitored. We found that both the kinetics of cell spreading and the static impedance-based cell index were feasible to distinguish the two cell types. At each given cell number, CAL 27 cell spreading produced a smaller cell index change rate that was 60-70% of those of Het-1A cells. When cells were fully spread, CAL 27 cells generated a cell index more than four times greater than that of Het-1A cells. Since cell spreading and attachment occurs in the first few hours when they were cultured on the microelectrodes, this impedance-based method could be a rapid label-free and non-invasive approach to distinguish oral cancer cells from non-cancer oral epithelial cells. Cell viability analysis was performed along with the impedance-based analysis. Confocal microscopic imaging analysis showed the difference in cell morphology and the thickness of cell monolayers between the two cell types.


Asunto(s)
Células Epiteliales/citología , Neoplasias de la Boca/patología , Adhesión Celular , Proliferación Celular , Supervivencia Celular , Células Cultivadas , Impedancia Eléctrica , Humanos , Cinética , Microelectrodos , Microscopía Confocal , Factores de Tiempo
6.
J Appl Dev Psychol ; 32(3): 127-136, 2011 05.
Artículo en Inglés | MEDLINE | ID: mdl-21607196

RESUMEN

This study examines how mothers with and without a history of childhood-onset depression respond to their 3-9 year-old children's emotions. Mother-child dyads included 55 offspring of mothers with a history of childhood-onset depressive disorders and 57 offspring of never-depressed mothers. Mothers with a history of childhood depression were less likely than were control mothers to respond in supportive ways to their children's negative emotions and were more likely to magnify, punish, or neglect their children's negative emotions. Magnification, neglect, and punishment of children's negative emotions were concurrently associated with children's internalizing symptoms, and neglect and punishment were associated with internalizing over a one year follow-up. Maternal neglect of children's negative emotion was positively associated with later internalizing symptoms for children who already had higher internalizing symptoms at the initial assessment. Findings suggest that atypical socialization of emotion may be one mechanism in the development of internalizing disorders.

7.
Am J Prev Med ; 57(4): 515-524, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31542129

RESUMEN

INTRODUCTION: A mandated reduction in the nicotine content of cigarettes may decrease smoking, but also increase demand for other nicotine products. The present study tested the impact of smoking cigarettes with very low nicotine content and concurrent use of a transdermal nicotine patch. STUDY DESIGN: A balanced 2 × 2 factorial randomized clinical trial investigating the impact of cigarette nicotine content (double-blind, very low nicotine content versus normal nicotine content) and use of a transdermal nicotine patch (open label, patch versus no patch). SETTING/PARTICIPANTS: Adult daily smokers (n=240) in the Pittsburgh, PA area. INTERVENTION: Participants were provided with research cigarettes and transdermal nicotine patches (if assigned to patch condition) for 7 weeks. Cigarettes were Spectrum brand (National Institute on Drug Abuse) and either 15.8 mg nicotine/g tobacco (normal nicotine content) or 0.4 mg nicotine/g tobacco (very low nicotine content). In the 7th week, participants were monetarily incentivized to abstain from smoking. MAIN OUTCOME MEASURES: Participants reported daily cigarette use throughout the trial and the primary outcome was average number of cigarettes smoked per day (study + nonstudy) during Week 6. Participants were recruited from 2015 to 2017 and data were analyzed between 2017 and 2018. RESULTS: Assignment to very low nicotine content cigarettes and assignment to wear a nicotine patch both reduced the number of cigarettes smoked per day during Week 6 (p=0.001 and 0.04, respectively). However, assignment to the patch along with very low nicotine content cigarettes did not significantly reduce cigarette smoking compared with assignment to very low nicotine content cigarettes alone. CONCLUSIONS: A mandated reduction in the nicotine content of cigarettes is likely to reduce the number of cigarettes smoked per day, but the added benefit of concurrent transdermal nicotine is unclear. Future studies should investigate whether alternative sources of noncombusted tobacco, such as e-cigarettes, enhance the effects of very low nicotine content cigarettes on smoking. TRIAL REGISTRATION: This study is registered at www.clinicaltrials.gov NCT02301325.


Asunto(s)
Fumar Cigarrillos/prevención & control , Nicotina/administración & dosificación , Cese del Hábito de Fumar/métodos , Productos de Tabaco/clasificación , Dispositivos para Dejar de Fumar Tabaco , Adulto , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud
8.
J Child Psychol Psychiatry ; 49(2): 132-41, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18211275

RESUMEN

BACKGROUND: This study examined preschoolers' emotion regulation (ER) strategies and the association with temperament, maternal interactive style, and maternal history of childhood-onset depression (COD). METHODS: Participants were 62 children and their mothers, 37 of whom had mothers with COD. Children's ER was assessed using a disappointment paradigm; temperament assessment also was laboratory-based. RESULTS: Maternal COD was inversely related to offspring's active ER and positive mood. Among children of COD mothers, behavioral inhibition was associated with passive regulation and sadness, and maternal positivity toward these children was associated with child active ER and positive mood. CONCLUSION: Behavioral inhibition may place children of COD mothers at risk for developing maladaptive ways of regulating negative emotion, whereas mothers' positivity may serve as a protective factor for them.


Asunto(s)
Adaptación Psicológica , Hijo de Padres Discapacitados/psicología , Trastorno Depresivo/psicología , Emociones , Relaciones Madre-Hijo , Responsabilidad Parental , Controles Informales de la Sociedad , Adulto , Afecto , Edad de Inicio , Preescolar , Femenino , Humanos , Inhibición Psicológica , Masculino , Modelos Psicológicos , Madres/psicología , Observación , Análisis de Regresión , Apoyo Social , Temperamento
9.
Contemp Clin Trials Commun ; 11: 69-74, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30023460

RESUMEN

Investigational tobacco products, specifically variable nicotine content research cigarettes (SPECTRUM), are available through the National Institute of Drug Abuse Drug Supply Program. Randomized controlled trials using research cigarettes are intended to support tobacco regulatory science research. The current paper provides an in-depth look into managing research cigarettes for two multi-site clinical trials and the design of a computer-based Cigarette Management System (CMS). The paper provides guidance intended for any investigator using similar products on the operating procedures under Good Clinical Practice standards and describes features of the CMS. The CMS and procedures described have been field tested for the past three years and have dispensed over 160,000 cigarette packs to participants. The CMS can accommodate a range of practical issues with real-world study implementation making it a robust application that is scalable to any study.

10.
J Fam Psychol ; 21(4): 714-25, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18179343

RESUMEN

This study examined the stability of the child and maternal affective expression and maternal responsiveness and the mutual influence of child and maternal expression of emotion. The authors tested whether maternal depression and child problem behavior were associated with the pattern of emotional exchange within the mother-child dyads. The sample consisted of 69 mother-child dyads (children aged 2-5 years), with 32 of the mothers having childhood-onset depression. Mothers were mostly stable in their affective expression (positive and negative) and responsiveness, whereas children were only stable in positive expression. Within the dyads, mothers seemed to play a more important role in regulating children's later emotional expression. Maternal depression was associated with concurrent maternal responsiveness and their reduced positive expression over time. Results are discussed in relation to the differential function of parental general positivity and responsiveness and the interpersonal transmission of emotional problems.


Asunto(s)
Trastornos de la Conducta Infantil/psicología , Conducta Infantil/psicología , Depresión/psicología , Emociones , Relaciones Madre-Hijo , Madres/psicología , Adulto , Síntomas Afectivos/psicología , Análisis de Varianza , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Responsabilidad Parental/psicología , Escalas de Valoración Psiquiátrica
11.
J Child Fam Stud ; 22(7): 893-902, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-24526827

RESUMEN

This study examines the psychometric properties and component structure of a newly developed observational system, the Aftercare and School Observation System (ASOS). Participants included 468 children drawn from a larger longitudinal intervention study. The system was utilized to assess participant children in school lunchrooms and recess and various afterschool environments. Exploratory factor analyses examined whether a core set of component constructs assessing qualities of children's relationships, caregiver involvement and monitoring, and experiences in school and aftercare contexts that have been linked to children's behavior problems would emerge. Construct validity was assessed by examining associations between ASOS constructs and questionnaire measures assessing children's behavior problems and relationship qualities in school and aftercare settings. Across both settings, two factors showed very similar empirical structures and item loadings, reflecting the constructs of a negative/aggressive context and caregiver positive involvement, with one additional unique factor from the school setting reflecting the extent to which caregiver methods used resulted in less negative behavior and two additional unique factors from the aftercare setting reflecting positivity in the child's interactions and general environment and negativity in the child's interactions and setting. Modest correlations between ASOS factors and aftercare provider and teacher ratings of behavior problems, adult-child relationships, and a rating of school climate contributed to our interpretation that the ASOS scores capture meaningful features of children's experiences in these settings. This study represents the first step of establishing that the ASOS reliably and validly captures risk and protective relationships and experiences in extra-familial settings.

12.
J Clin Child Adolesc Psychol ; 35(1): 116-26, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16390307

RESUMEN

This study tests a model of children's emotion regulation (ER) as a moderator of the link between maternal depression and child internalizing problems. Participants were 78 children (ages 4 to 7), including 45 children of mothers with a history of childhood-onset depression (COD) and 33 children of mothers who had never been depressed. ER was assessed observationally during a laboratory mood induction. ER behaviors were empirically reduced into 3 categories: (a) negative focus on delay, (b) positive reward anticipation, and (c) behavioral distraction. Linear mixed models indicated that positive reward anticipation moderated the effects of maternal COD on children's internalizing problems, particularly if mothers had current depressive symptoms. Findings suggest that generating positive affect in the face of a potential frustration may be a protective ER strategy for children at risk for depression.


Asunto(s)
Afecto , Hijo de Padres Discapacitados/psicología , Trastorno Depresivo Mayor/epidemiología , Trastorno Depresivo Mayor/psicología , Relaciones Madre-Hijo , Madres/psicología , Controles Informales de la Sociedad , Adulto , Índice de Masa Corporal , Niño , Trastorno Depresivo Mayor/diagnóstico , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Estudios de Seguimiento , Humanos , Masculino , Psicología Infantil
13.
J Child Psychol Psychiatry ; 47(9): 960-9, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16930391

RESUMEN

BACKGROUND: Family process variables have been linked to child problem behavior, but recent research suggests that child ethnicity may moderate relations between family process and child outcomes. The current study examined how ethnicity moderates relations between parent conflict, parent-child relationship quality, and internalizing problems. METHODS: A sample of 101 mother-child dyads was drawn from a larger longitudinal study of childhood-onset depression. Maternal reports of family process factors were used with child reports of anxiety and depressive symptoms. RESULTS: The results indicated a moderating effect of ethnicity for multiple indicators of internalizing symptoms, such that child-rearing disagreement and low levels of mother-child openness were associated with internalizing problems only for European American (not African American) children. CONCLUSIONS: Findings suggest that ethnicity moderates the effects of family process factors on child psychopathology. Ethnic differences may be accounted for by the normativeness of family processes and the meaning that children of different ethnic backgrounds assign to these processes.


Asunto(s)
Conflicto Psicológico , Etnicidad/psicología , Etnicidad/estadística & datos numéricos , Familia/psicología , Padres/psicología , Adolescente , Adulto , Negro o Afroamericano/psicología , Negro o Afroamericano/estadística & datos numéricos , Trastornos de Ansiedad/diagnóstico , Trastornos de Ansiedad/epidemiología , Trastornos de Ansiedad/psicología , Niño , Crianza del Niño , Demografía , Trastorno Depresivo Mayor/diagnóstico , Trastorno Depresivo Mayor/epidemiología , Trastorno Depresivo Mayor/psicología , Estudios de Seguimiento , Humanos , Entrevista Psicológica , Relaciones Madre-Hijo , Encuestas y Cuestionarios , Población Blanca/psicología , Población Blanca/estadística & datos numéricos
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