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1.
J Biomed Inform ; 119: 103817, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34020026

RESUMEN

Patient context - the "envirome" - can have a significant impact on patient health. While envirome indicators are available through large scale public data sources, they are not provided in a format that can be easily accessed and interpreted at the point of care by healthcare providers with limited time during a patient encounter. We developed a clinical decision support tool to bring envirome indicators to the point of care in a large pediatric hospital system in the Kansas City region. The Envirome Web Service (EWS) securely geocodes patient addresses in real time to link their records with publicly available context data. End-users guided the design of the EWS, which presents summaries of patient context data in the electronic health record (EHR) without disrupting the provider workflow. Through surveys, focus groups, and a formal review by hospital staff, the EWS was deployed into production use, integrating publicly available data on food access with the hospital EHR. Evaluation of EWS usage during the 2020 calendar year shows that 1,034 providers viewed the EWS, with a total of 29,165 sessions. This suggests that the EWS was successfully integrated with the EHR and is highly visible. The results also indicate that 63 (6.1%) of the providers are regular users that opt to maintain the EWS in their custom workflows, logging more than 100 EWS sessions during the year. The vendor agnostic design of the EWS supports interoperability and makes it accessible to health systems with disparate EHR vendors.


Asunto(s)
Sistemas de Apoyo a Decisiones Clínicas , Sistemas de Atención de Punto , Niño , Comercio , Registros Electrónicos de Salud , Humanos , Flujo de Trabajo
2.
Environ Health Perspect ; 109(5): 501-7, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11401762

RESUMEN

It has been hypothesized that the increased incidence of breast cancer in industrial societies is related to greater exposure to power-frequency electric and magnetic fields (EMF) and/or the presence of high levels of light at night (LAN). EMF and LAN are said to reduce circulating levels of the hormone melatonin which, in turn, allows estrogen levels to rise and stimulate the turnover of breast epithelial stem cells and increase the risk for malignant transformation. Three laboratory-based studies, in which a total of 53 healthy young women were exposed at night to EMF or to LAN under controlled exposure conditions, were performed to determine whether such exposures reduce melatonin and are associated with further alterations in estrogen. All-night exposure to industrial-strength magnetic fields (60 Hz, 28.3 microT) had no effect on the blood levels of melatonin or estradiol. In contrast, nocturnal melatonin levels were profoundly suppressed, and the time of peak concentration was significantly delayed in women exposed to LAN, regardless of whether they were in the follicular or luteal phase of the menstrual cycle. These changes, however, were not associated with alterations in point-for-point matching measures of estradiol. Women who chronically secrete high or low amounts of melatonin each night (area-under-curve range: 86-1,296 pg/mL) also did not differ in their blood levels of estradiol. Taken together, these results are consistent with a growing body of evidence which generally suggests that environmental EMF exposure has little or no effect on the parameters measured in this report.


Asunto(s)
Neoplasias de la Mama/etiología , Campos Electromagnéticos/efectos adversos , Exposición a Riesgos Ambientales/efectos adversos , Estradiol/sangre , Luz/efectos adversos , Melatonina/sangre , Adulto , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos
3.
Environ Health Perspect ; 108(8): 737-42, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10964794

RESUMEN

Heart rate variability (HRV), a noninvasive indicator of autonomic control of cardiac activity, is predictive of long-term cardiac morbidity and mortality. Epidemiologic research suggests that occupational exposure to power-frequency magnetic fields may be associated with autonomically mediated cardiac mortality. Results from our laboratory studies of humans exposed to 60-Hz magnetic fields overnight, however, are inconsistent. HRV is altered in some studies but not others. To clarify this, the pooled data from seven studies involving 172 men were analyzed to test specific hypotheses concerning this inconsistency. After analysis, we excluded a) measurement drift or instability over time because HRV was stable under sham-exposed conditions across all studies; b) inadequate statistical power or failure to maintain double-blind controls; c) differences in field intensity (28.3 vs. 127.3 microT) or exposure pattern (intermittent versus continuous) as main effects; or d) the inclusion of individuals sensitive to magnetic field exposure in some studies but not others. Four separate analytic techniques failed to identify a valid subpopulation of sensitive individuals. In some studies, however, hourly blood samples were collected using an indwelling venous catheter. HRV alterations occurred during intermittent exposure in these studies (p < 0.05) but not in similar studies without blood sampling. This result suggests a field interaction with modest arousal or disturbance. Because HRV is tightly coupled to electroencephalographic activity during sleep, these results are physiologically plausible and suggest that HRV alterations during exposure to magnetic fields may occur when accompanied by increases in physiologic arousal, stress, or sleep disturbance.


Asunto(s)
Arritmias Cardíacas/epidemiología , Arritmias Cardíacas/etiología , Campos Electromagnéticos/efectos adversos , Exposición a Riesgos Ambientales/estadística & datos numéricos , Adolescente , Adulto , Ritmo Circadiano/efectos de la radiación , Electroencefalografía , Humanos , Masculino , Sueño/efectos de la radiación
4.
Clin Neurophysiol ; 111(11): 1936-41, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11068226

RESUMEN

OBJECTIVE: To determine if controlled exposure to power-frequency magnetic fields alters heart rate variability (HRV) and polysomnographic endpoints in healthy men (n=22) and women (n=24), 40-60 years of age. METHODS: A randomized, double-blind, crossover design was used. Study endpoints collected during all-night exposure to 60 Hz magnetic fields at an occupational intensity (resultant flux density=28.3 microTesla, microT) were compared to similar endpoints obtained under equivalent, counterbalanced, no-exposure (< or =0.2 microT) control conditions. RESULTS: Older men, but not women, exposed to the magnetic fields showed power reductions in the LF band of the HRV frequency spectrum, which is associated with sympathetically-mediated blood pressure and thermoregulatory control (P<0.04). Older women, but not men, exposed to the fields showed a pattern of disrupted sleep, with reductions in the duration of REM sleep (P=0.03), and strong trends for reductions in sleep efficiency (P=0.06) and total sleep time (P=0.06). CONCLUSIONS: The gender-specific effects seen here with older volunteers replicate the results of previous exposure studies with younger men and women.


Asunto(s)
Frecuencia Cardíaca/fisiología , Magnetismo , Sueño/fisiología , Adulto , Factores de Edad , Presión Sanguínea/fisiología , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polisomnografía
5.
Health Psychol ; 6(6): 561-8, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3691454

RESUMEN

Salivary samples from three placement sites and under stimulated and unstimulated flow-rate conditions were collected from 36 participants (18 smokers, 18 nonsmokers) on each of 3 days. These samples were used to determine the best collection methodology for discriminating smokers from nonsmokers, the reliability of salivary thiocyanate (SCN) over days, and the stability of SCN given varying storage treatments. Results showed that SCN levels were significantly higher in smokers than in nonsmokers, in parotid site collections than either sublingual or mixed collections, and in unstimulated collections. Stimulated, mixed samples were reliable across days and were the best discriminator of smokers and nonsmokers. SCN levels did not differ under varying storage treatments. It is recommended that a standard methodology for collecting stimulated, mixed saliva be used when measuring SCN levels.


Asunto(s)
Saliva/metabolismo , Fumar/metabolismo , Tiocianatos/metabolismo , Femenino , Humanos , Masculino , Fumar/terapia
6.
J Consult Clin Psychol ; 59(2): 351-3, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2030199

RESUMEN

Previous investigations of smoking relapse crises have found limited within-subject consistency. Several investigators have suggested that greater consistency might be observed if situations were described phenomenologically. Reversal theory provides one phenomenological framework. Two relapse crises from each of 49 ex-smokers were compared, using reversal theory constructs. Maintaining abstinence in both crises was consistently associated with being in serious-minded (telic) and conformist states. Smoking in both crises was consistently associated with being in playful (paratelic) or negativistic states. Crises with different outcomes occurred in different state combinations. The findings suggest that coping strategies should be state-tailored for optimal effectiveness.


Asunto(s)
Adaptación Psicológica , Motivación , Fumar/psicología , Medio Social , Adulto , Femenino , Estudios de Seguimiento , Humanos , Individualidad , Masculino , Persona de Mediana Edad , Recurrencia , Fumar/terapia
7.
J Consult Clin Psychol ; 58(4): 489-94, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2212187

RESUMEN

Reversal theory provides a new approach to understanding ex-smokers' behavior during highly tempting situations. Hypotheses derived from the theory were tested in 2 studies of the highly tempting situations of ex-smokers drawn from community smoking cessation programs. Study 1 consisted of interviews with 55 Ss (25 men and 30 women, mean age 37 years) conducted 3 months after cessation. Study 2 consisted of interviews with 104 Ss (45 men and 59 women, mean age 41 years) conducted 6, 9, 12, and 15 months after cessation. All interviews were coded using reversal theory constructs. Results supported the hypotheses that individuals in paratelic or negativistic states were more likely to lapse than individuals in telic/conformist states and that cigarette availability was related to lapses in paratelic, but not telic, states. Reversal theory constructs accurately classified 93% and 85% of the cases, suggesting that the theory provides an improved model for understanding behavior during highly tempting situations.


Asunto(s)
Nivel de Alerta , Prevención del Hábito de Fumar , Facilitación Social , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Factores de Riesgo , Fumar/psicología
8.
Int J Psychophysiol ; 23(1-2): 101-10, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8880370

RESUMEN

Concepts from reversal theory, a general theory of motivation, emotion and action, have recently been shown to be relevant to smoking behavior and smoking cessation. One relevant concept is that of telic and paratelic dominance. Individuals who are paratelic-dominant are playful, spontaneous, and prefer high arousal seeking. Those who are telic-dominant are serious, tend to plan ahead, and prefer low arousal. This led to the hypothesis that smoking might increase the amplitude of the contingent negative variation (CNV) in paratelic-dominant smokers more than in telic-dominant smokers. CNV was obtained using a Go/NoGo reaction time task with a 2 s S1-S2 interval and variable intertrial intervals. S1 indicated whether the subject was to respond to S2 or not. Errors were punished with a burst of white noise. Subjects performed the CNV task three times: after being deprived of smoking for at least 4 h; after sham smoking; and after smoking a cigarette of their own brand. Telic-dominant subjects differed from paratelic-dominant subjects in the relative amplitude of early (1 s) and late (2 s) components of the CNV. Smoking did not differentially affect the dominance groups unless gender was taken into account, and the most striking interactions between smoking and dominance groups were noted for the NoGo trials. As expected, smoking decreased the amplitude of the early component of the NoGo CNV for telic-dominant women, but increased it for paratelic-dominant women; no significant differences were found for the late component. In men, smoking increased the late CNV more for telics than for paratelics, while smoking did not differentially affect the early component.


Asunto(s)
Variación Contingente Negativa/efectos de los fármacos , Dominancia Cerebral/fisiología , Fumar/psicología , Estimulación Acústica , Adolescente , Adulto , Afecto , Electroencefalografía , Extraversión Psicológica , Femenino , Lateralidad Funcional/fisiología , Humanos , Masculino , Persona de Mediana Edad , Inventario de Personalidad , Tiempo de Reacción/fisiología , Caracteres Sexuales , Cese del Hábito de Fumar/psicología
9.
Int J Psychophysiol ; 33(2): 169-75, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10489081

RESUMEN

The neurophysiological effects of exposure to power-frequency magnetic fields at two occupationally-relevant intensities were evaluated in a single-blind study with 18 male and 18 female volunteers. Auditory brainstem (BAEP) and somatosensory (SEP) evoked potentials were recorded before, during and after field exposure (duration = 45 min, frequency = 60 Hz, field intensities = 14.1 or 28.3 microtesla, microT), or an equivalent sham-exposure control period. Visual event-related potentials (VEP) to pattern reversal stimuli were also recorded before and after the exposure period. Field exposure had no differential effects on the BAEP, the VEP, or on SEP measures of central conduction time. Men and women showed a similar lack of sensitivity to exposure. The present results do not support the mechanistic hypothesis that the transmission of sensory information to appropriate cortical centers is delayed or distorted by exposure to power-frequency magnetic fields at occupational intensities.


Asunto(s)
Campos Electromagnéticos/efectos adversos , Fenómenos Fisiológicos del Sistema Nervioso/efectos de la radiación , Adolescente , Adulto , Potenciales Evocados Auditivos del Tronco Encefálico/fisiología , Potenciales Evocados Somatosensoriales/fisiología , Femenino , Humanos , Masculino , Reconocimiento Visual de Modelos/fisiología , Método Simple Ciego , Transmisión Sináptica/fisiología
10.
Int J Psychophysiol ; 19(3): 247-56, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7558991

RESUMEN

Reversal theory, a general theory of motivation, emotion and action, has recently been shown to predict lapses in smoking cessation. Individuals are less likely to lapse if they are in the telic (serious-minded, arousal avoidant, goal-oriented) state than when they are in the paratelic (playful, arousal seeking, spontaneous) state. The literature indicates that people can smoke in such a way as to either increase or decrease central nervous system arousal; smoking in the telic and paratelic states might therefore differentially affect the resting electroencephalograph, as quantified by Fast Fourier Transform analysis. The basic hypothesis was supported. Theta power was decreased when subjects in the telic state smoked, while beta 2 power was increased when subjects in the paratelic state smoked; the latter finding was, however, true only for men. The results have important implications for research on changing health behaviors and for smoking cessation programs.


Asunto(s)
Nivel de Alerta/fisiología , Electroencefalografía , Personalidad , Fumar/fisiopatología , Fumar/psicología , Adolescente , Adulto , Femenino , Análisis de Fourier , Humanos , Masculino , Persona de Mediana Edad
11.
Addict Behav ; 13(4): 383-6, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3239470

RESUMEN

This study investigated the effects of salivary stimulation on thiocyanate (SCN) levels. A device for collecting parotid saliva that allowed for the measurement of flow rate was used in stimulated and nonstimulated conditions with six subjects. Results indicated that SCN levels exhibited considerable within-subject variability and were inversely related to flow rate. Under stimulated conditions, SCN levels stabilized in 3 min. Under nonstimulated conditions. SCN levels stabilized in 26 min. Although mean SCN levels were higher for smokers than nonsmokers, considerable overlap was observed such that misclassification of both smokers and nonsmokers could occur if cut-off points were not adjusted for flow rate conditions. Suggestions for standardizing stimulated conditions for collecting salivary SCN samples are discussed.


Asunto(s)
Saliva/metabolismo , Salivación , Fumar/metabolismo , Tiocianatos/metabolismo , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
12.
Res Rep Health Eff Inst ; (42): 1-45, 1991 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1930768

RESUMEN

Methanol could become an important motor fuel. The objective of this exploratory study was to provide preliminary information about whether or not acute exposure to methanol at 250 mg/m3 for 75 minutes would have adverse effects on human neurobehavioral functions important in everyday life. This concentration level was selected because it is at the upper limit of the traffic scenario estimates provided by the U.S. Environmental Protection Agency (EPA)2 (86 to 240 mg/m3), but is below the maximum concentrations for eight-hour average exposures currently recommended by the National Institute of Occupational Safety and Health (NIOSH) and the American Conference of Government and Industrial Hygienists (ACGIH) (260 mg/m3). Although traffic scenario exposure estimates suggest that such high levels of exposure last less than 15 minutes, we used a 75-minute exposure to increase the probability of identifying dependent measures that should be studied in more detail in a future confirmatory study. Twelve healthy young men, each serving as his own control, participated in two sham exposures and two methanol exposures under counterbalanced, double-blind control conditions. Because methanol is present in many foods, and because high preexposure levels of methanol or formate might obscure exposure effects, subjects were required to strictly limit their diets for 12 hours before each experimental session. The following endpoints were examined before, during, and after exposure to methanol and sham vapors: blood and urinary methanol; plasma formate; oral temperature; blood pressure; subjective mood, alertness, fatigue, workload, and symptom scales; spectral analysis of the electroencephalogram; visual- and auditory-event-related potentials; contingent negative variation; respiration; cardiac interbeat interval; Symbol Digit substitution task; three-choice reaction time; Stroop color-word test; simple reaction time; visual function; critical flicker fusion frequency; hand steadiness; visual search task; Gamberale reaction time task; visual tracking task; Sternberg memory task; interval production task; and speeded addition task. Two dual tasks were also included in the task batteries. These endpoints were selected from those indicated in the literature to be sensitive to solvents, and from those that are widely used in other neurobehavioral test batteries to identify the effects of environmental pollutants. Because the number of endpoints examined was large and the number of subjects was small, procedures designed to reduce the number of statistical tests performed were used. Mean methanol concentration in the exposure room during methanol exposures was 249 mg/m3 (SD +/- 7 mg/m3). Exposure produced significant increases in blood and urine methanol concentration. As expected, no changes in plasma formate were observed.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Metanol/toxicidad , Desempeño Psicomotor/efectos de los fármacos , Adulto , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/metabolismo , Líquidos Corporales/química , Cognición/efectos de los fármacos , Método Doble Ciego , Fatiga/inducido químicamente , Fatiga/epidemiología , Humanos , Masculino , Metanol/análisis , Metanol/metabolismo , Pruebas Neuropsicológicas , Carga de Trabajo
13.
Aviat Space Environ Med ; 72(12): 1102-6, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11763111

RESUMEN

BACKGROUND: Pretreatment with pyridostigmine bromide (PB) has become part of standard military procedures for protection against the effects of possible chemical warfare attack. The purpose of the work reported here was to quantify the type, intensity and frequency of side effects of low-dose PB, and to examine factors that predict the intensity and frequency of side effects. METHOD: A double-blind, cross-over, placebo (PL)-controlled design was used. Of the 67 subjects, 33 received 30 mg PB every 8 h for 13 doses, and 34 received 60 mg on the same schedule. Order of PB and PL administration was counterbalanced. RESULTS: Overall, side effects were mild, even at the 60-mg dose level. More side effects were reported when volunteers were taking PB than when they were taking placebo. Women reported more symptoms than men. Neither cholinesterase inhibition nor plasma levels of PB predicted side effect scores during the PB week; the best predictor of side effect scores during the PB week was side effect scores during the PL week. CONCLUSION: PB is well tolerated by healthy young people, even when twice the recommended military dose is administered.


Asunto(s)
Inhibidores de la Colinesterasa/administración & dosificación , Inhibidores de la Colinesterasa/efectos adversos , Bromuro de Piridostigmina/administración & dosificación , Bromuro de Piridostigmina/efectos adversos , Adolescente , Adulto , Inhibidores de la Colinesterasa/sangre , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Masculino , Bromuro de Piridostigmina/sangre
14.
J Nurs Meas ; 8(2): 145-60, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11227581

RESUMEN

This study presents the development and testing of the Overeating Tension Scale. Overeating tension was defined operationally as the total discrepancy score resulting from differences between subjects' ratings of actual and desired feelings before overeating. The 32-item Overeating Tension Scale, derived from Apter's Reversal Theory, measures reported overall tension and motivation-specific tension. The scale initially included 48 items, six items for each of eight motivational states. After two instrument development studies (N = 373, N = 208), items were refined and reduced to a total of 32, or four for each of eight motivational states. The final version of the instrument was tested in two additional studies (N = 330, N = 130) that provided evidence to support the internal consistency reliability of the Overeating Tension Scale. There was support for construct validity using contrasted groups (overweight and normal weight subjects), convergent validity, and factor analysis.


Asunto(s)
Hiperfagia/diagnóstico , Evaluación en Enfermería/métodos , Estrés Psicológico/diagnóstico , Encuestas y Cuestionarios , Adulto , Análisis Factorial , Femenino , Humanos , Hiperfagia/psicología , Masculino , Motivación , Reproducibilidad de los Resultados , Estrés Psicológico/complicaciones , Estados Unidos
17.
J Pineal Res ; 28(1): 1-8, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10626595

RESUMEN

Magnetic field-induced suppression of nocturnal melatonin in humans has been reported in occupational and residential studies, but not in laboratory-based exposure studies. The present study examined whether this contrasting pattern of results might be related to associated differences in exposure duration or to field-induced measurement instability over time. Thirty healthy young men were evaluated using a randomized, double-blind test protocol. Statistical analysis indicated that 4 consecutive nights of exposure to power-frequency magnetic fields at occupational intensity (resultant flux density = 28.3 microtesla, muT, [283 milligauss, mG]) had no differential effect on concentrations of melatonin or its major enzymatic metabolite (6-hydroxymelatonin sulfate, 6-OHMS) in daily morning urine samples, compared to equivalent no-exposure sham control conditions. The consistency of intra-individual urinary measurements over the 4 test nights also was quite high (P < 0.01) in the sham control condition. In contrast, repeated nightly exposure to the magnetic field was associated with reduced consistency. Morning urinary measures obtained after exposure on night 4 differed (P < 0.01) from similar measures obtained after the second and third exposure night. Thus, while the overall results of this study do not support the melatonin hypothesis, there is some suggestion of a possible cumulative effect of magnetic field exposure on the stability of individual melatonin measurements over time. Additional research with longer periods of controlled exposure may be warranted.


Asunto(s)
Campos Electromagnéticos/efectos adversos , Melatonina/análogos & derivados , Melatonina/orina , Glándula Pineal/efectos de la radiación , Adolescente , Adulto , Ritmo Circadiano , Método Doble Ciego , Humanos , Masculino , Glándula Pineal/metabolismo
18.
Bioelectromagnetics ; 13(4): 261-85, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1510736

RESUMEN

The purpose of this study was to reproduce and extend an earlier investigation of the effects of human exposure to combined, 60-Hz electric and magnetic fields. This paper presents the neurobehavioral results. Thirty men participated in one training session and four testing sessions. Subjects were randomly assigned to two groups. The 18 subjects in Group I were exposed (9 kV/m, 20 microT) and sham exposed in two counterbalanced orders. In Group II, half of 12 subjects were exposed (9 kV/m, 20 microT) every session, and the remaining half were sham exposed every session. The study was doubly blinded. Measures of cardiac interbeat interval, event-related brain potentials, and performance were obtained before, during, and after exposures. As in the earlier study, exposure to the combined field resulted in a statistically significant slowing of heart rate, in changes in late components of event-related brain potentials, and in decreased errors on a choice reaction-time task. In addition, field effects on several other measures approached statistical significance. The physiological measures obtained during exposure indicated that effects were greatest soon after the field was switched on, and again when it was switched off. The data indicate that changes in exposure level may be more important than duration of exposure for producing effects in human beings.


Asunto(s)
Electroencefalografía , Campos Electromagnéticos , Exposición a Riesgos Ambientales , Frecuencia Cardíaca , Análisis y Desempeño de Tareas , Adulto , Método Doble Ciego , Humanos , Masculino
19.
Bioelectromagnetics ; 17(4): 263-73, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8891185

RESUMEN

Two double-blind laboratory-based studies were performed to determine whether a suppression of nocturnal melatonin similar to that observed in rodents occurs when humans are exposed to magnetic fields at night. In study 1, 33 men were exposed to sham, 10 mG, or 200 mG intermittent, circularly polarized magnetic fields from 2300 to 0700 h under controlled environmental and exposure test conditions. Overall, exposure had no effect on melatonin levels. Men with preexisting low levels of melatonin, however, showed significantly greater suppression of melatonin when they were exposed to light and also when they were exposed to the 200 mG magnetic-field condition. Study 2 directly tested the hypothesis that low-melatonin subjects show enhanced sensitivity when exposed to light and to 200 mG magnetic fields. After preexposure screening, each of 40 men slept in the exposure facility on two nights. On one night, the men were sham exposed. On the other night, they were exposed to the 200 mG field condition used previously. Again, exposure had no overall effect on melatonin levels. The original finding of enhanced sensitivity in low-melatonin subjects was not replicated in this study. We conclude that the intermittent exposure conditions used in these two studies were not effective in altering nocturnal melatonin release patterns in human volunteers. Further research is underway with regard to exposure parameters, hormonal and immune system measures, and individual differences.


Asunto(s)
Ritmo Circadiano/fisiología , Magnetismo/efectos adversos , Melatonina/sangre , Adolescente , Adulto , Animales , Método Doble Ciego , Humanos , Luz , Masculino , Melatonina/metabolismo
20.
Image J Nurs Sch ; 27(4): 311-6, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8530121

RESUMEN

Relapse is the most frequent outcome of smoking cessation attempts. This study tests the usefulness of the mastery and sympathy concepts of Apter's reversal theory to explain whether subjects lapse or abstain during highly tempting situations. Descriptions of the highly tempting situations of 57 individuals who were attempting to quit smoking were assigned to mastery or sympathy categories. Situations were also coded for availability of cigarettes. Logit modeling revealed that both the mastery/sympathy variable and the availability of cigarettes were necessary to fit the data. Being in the mastery state and having to exert effort to get cigarettes were significantly related to resisting the urge to smoke. The smoking status of 36% of the subjects was correctly classified using both variables. The usefulness of mastery/sympathy states in explaining relapses in behavior change is discussed.


Asunto(s)
Afecto , Motivación , Teoría Psicológica , Cese del Hábito de Fumar/psicología , Adulto , Distribución de Chi-Cuadrado , Femenino , Humanos , Modelos Logísticos , Masculino , Medio Oeste de Estados Unidos , Autoimagen
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