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1.
Epilepsy Behav ; 25(4): 666-9, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23168090

RESUMEN

Psychogenic nonepileptic seizures (PNES) and psychogenic movement disorders (PMD) are common and disabling problems with abnormal psychological profiles, and they may have common features that could aid in better understanding and management. Since PNES and PMD are investigated and reported separately, comparisons are lacking. Psychogenic nonepileptic seizure and psychogenic movement disorder patients completed demographic, clinical, and psychological inventories including the Short Form (SF)-12 Health Status Survey (Physical and Mental Health Summary Scores), the Brief Symptom Inventory (BSI)-18 (somatization, depression, and anxiety subscales), and the Lorig Self-Efficacy Scale. Psychogenic nonepileptic seizure and psychogenic movement disorder patients had similar psychological profiles with reduced SF-12 Physical Health and Mental Health Summary Scores and increased BSI somatization, depression, and anxiety ratings. They varied slightly in age and gender, but their main distinguishing features were the presenting signs. These similar profiles suggest that PNES and PMD may not be distinct or separate entities and that collaborative investigative efforts and management are warranted.


Asunto(s)
Trastornos del Movimiento/diagnóstico , Convulsiones/diagnóstico , Adulto , Femenino , Estado de Salud , Humanos , Masculino , Persona de Mediana Edad , Trastornos del Movimiento/psicología , Pruebas Neuropsicológicas , Escalas de Valoración Psiquiátrica , Pruebas Psicológicas , Psicología , Convulsiones/psicología , Autoeficacia
2.
J Nephrol ; 35(6): 1753-1757, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34739712

RESUMEN

Necrobiotic xanthogranuloma (NXG) is a rare non-Langerhans cell histiocytosis with characteristic cutaneous features and rare visceral involvement. More than 80% of individuals with this disease have a detectable paraprotein but the precise pathogenesis remains obscure. A 68-year-old man with known cutaneous necrobiotic xanthogranuloma presented with acute kidney injury and imaging suggestive of bilateral perinephric infiltration. Renal biopsy showed a prominent histiocytic infiltration of renal capsule and cortex with necrobiosis and characteristic 'Touton-type' giant cells suggestive of necrobiotic xanthogranuloma involvement. Kidney function returned to normal and cutaneous lesions improved with a combination of corticosteroid, chlorambucil and rituximab. This case represents only the second reported incidence of kidney involvement by necrobiotic xanthogranuloma and the first with acute kidney injury and pre-mortem histopathology. This report adds to a small body of literature on the diagnosis and management of visceral involvement by this rare disease.


Asunto(s)
Lesión Renal Aguda , Xantogranuloma Necrobiótico , Paraproteinemias , Anciano , Biopsia , Humanos , Riñón/patología , Masculino , Xantogranuloma Necrobiótico/diagnóstico , Xantogranuloma Necrobiótico/tratamiento farmacológico , Xantogranuloma Necrobiótico/patología , Paraproteinemias/complicaciones , Paraproteinemias/diagnóstico
3.
Exp Brain Res ; 202(1): 129-45, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20012530

RESUMEN

To view different objects of interest, primates use fast, accurate eye movements called saccades. If saccades become inaccurate, the brain adjusts their amplitudes so they again land on target, a process known as saccade adaptation. The different types of saccades elicited in different behavioral circumstances appear to utilize different parts of the oculomotor circuitry. To gain insight into where adaptation occurs in different saccade pathways, we adapted saccades of one type and examined how that adaptation affected or transferred to saccades of a different type. If adaptation of one type of saccade causes a substantial change in the amplitude of another, that adaptation may occur at a site used in the generation of both types of saccade. Alternatively, if adaptation of one type of saccade transfers only partially, or not at all, to another, adaptation occurs at least in part at a location that is not common to the generation of both types of saccade. We produced significant amplitude reductions in memory-guided, delayed, targeting and express saccades by moving the target backward during the saccade. After memory-guided saccades were adapted, the amplitude of express, targeting and delayed saccades exhibited only a partial reduction. In contrast, when express, targeting, or delayed saccades were adapted, amplitude transfer to memory-guided saccades was more substantial. These results, combined with previously published data, suggest that there are at least two sites of adaptation within the saccadic system. One is used communally in the generation of express, targeting, delayed and memory-guided saccades, whereas the other is specific for the generation of memory-guided saccades.


Asunto(s)
Adaptación Psicológica , Desempeño Psicomotor , Movimientos Sacádicos , Adulto , Señales (Psicología) , Medidas del Movimiento Ocular , Humanos , Memoria , Estimulación Luminosa , Psicofísica , Factores de Tiempo
4.
Vision Res ; 46(19): 3121-8, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16698057

RESUMEN

When saccades become inaccurate, their amplitude is adapted. We examined, in humans, whether this adaptation occurs where the saccade is represented as a vector or as its horizontal and vertical components. In one experiment, we behaviorally reduced the amplitude of clockwise oblique saccades and examined the transfer to saccades made to other target amplitudes and directions. In a second, we adapted rightward saccades of the same size as the rightward component of the clockwise oblique saccades and examined the effect on oblique saccades. The results of both experiments imply that adaptation occurs where the saccade command is represented as a vector.


Asunto(s)
Adaptación Ocular , Modelos Psicológicos , Movimientos Sacádicos , Adulto , Anciano , Humanos , Persona de Mediana Edad , Estimulación Luminosa , Psicofísica
5.
Prog Neurobiol ; 72(1): 27-53, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15019175

RESUMEN

Saccadic eye movements are shifts in the direction of gaze that rapidly and accurately aim the fovea at targets of interest. Saccades are so brief that visual feedback cannot guide them to their targets. Therefore, the saccadic motor command must be accurately specified in advance of the movement and continually modified to compensate for growth, injury, and aging, which otherwise would produce dysmetric saccades. When a persistent dysmetria occurs in subjects with muscle weakness or neural damage or is induced in normal primates by the surreptitious jumping of a target forward or backward as a saccade is made to acquire the target, saccadic amplitude changes to reduce the dysmetria. Adaptation of saccadic amplitude or direction occurs gradually and is retained in the dark, thus representing true motor plasticity. Saccadic adaptation is more rapid in humans than in monkeys, usually is incomplete in both species, and is slower and less robust for amplitude increases than decreases. Adaptation appears to be motor rather than sensory. In humans, adaptation of saccades that would seem to require more sensory-motor processing does not transfer to saccades that seem to require less, suggesting the existence of distributed adaptation loci. In monkeys, however, transfer from more simple to more complex saccades is robust, suggesting a common adaptation site. Neurophysiological data from both species indicate that the oculomotor cerebellum is crucial for saccadic adaptation. This review shows that the precise, voluntary behaviors known as saccadic eye movements provide an alternative to simple reflexes for the study of the neuronal basis of motor learning.


Asunto(s)
Adaptación Fisiológica/fisiología , Plasticidad Neuronal/fisiología , Movimientos Sacádicos/fisiología , Animales , Conducta Animal , Encéfalo/anatomía & histología , Encéfalo/fisiología , Retroalimentación/fisiología , Humanos , Red Nerviosa/fisiología , Percepción Visual/fisiología
6.
Metabolism ; 40(3): 223-5, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2000033

RESUMEN

The effects of insulin and glucose on triacylglycerol (TG) metabolism in normal and diabetic isolated skeletal muscle were investigated in this study. Intracellular TG was continuously synthesized and hydrolyzed in both normal and diabetic skeletal muscle. In the absence of insulin and glucose, normal and diabetic skeletal muscle TG content and synthesis were decreased. In contrast, in the presence of insulin and glucose, the normal and diabetic TG contents were unchanged and triacylglycerol synthesis was increased as compared with the respective control values. However, insulin and glucose increased intramuscular TG content to a greater extent than could be accounted for by their stimulation of TG synthesis, indicating that insulin and glucose appear to inhibit TG hydrolysis in diabetic muscle, as well as in normal muscle. In addition, these data suggest that diabetes causes a defect in the ability of insulin and glucose to stimulate TG synthesis, as the increase in diabetic muscle TG synthesis in the presence of insulin and glucose was less than in normal muscle.


Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Glucosa/farmacología , Insulina/farmacología , Músculos/metabolismo , Triglicéridos/metabolismo , Animales , Ácidos Grasos no Esterificados/metabolismo , Técnicas In Vitro , Ratas , Valores de Referencia
7.
J Appl Physiol (1985) ; 68(6): 2473-81, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2200780

RESUMEN

Little is known about the contribution of plasma free fatty acid (FFA) and intramuscular triacylglycerol (TG) as substrates for energy production during prolonged electrical stimulation of skeletal muscle. The purpose of this study was to investigate the effects of continuous and intermittent electrical stimulation protocols of different intensities on exogenous FFA oxidation, exogenous FFA incorporation into intracellular TG, and intracellular TG content in the isolated in vitro rat flexor digitorum brevis muscle preparation. Muscles were electrically stimulated for 0.5 h continuously at 0.2 Hz or intermittently (30 s on, 60 s off) at 0.2, 0.4, 0.8, and 5.0 Hz while incubated at 37 degrees C in 0.5 mM palmitate-3% bovine serum albumin medium (pH 7.4) in the presence of insulin (100 microU/ml) and glucose (11 mM). Control muscles were frozen immediately after excision or incubated for 0.5 h. At similar frequencies, less exogenous FFA esterification and more exogenous FFA oxidation occurred during continuous than during intermittent stimulation. As the frequency of intermittent stimulation increased, the amount of exogenous FFA esterified decreased and the amount of exogenous FFA oxidized increased. The data also indicate that at least a portion of TG was constantly being hydrolyzed during electrical stimulation. Under stimulation conditions in which exogenous FFA esterification was below the control (resting muscle) level, intramuscular TG content was significantly decreased compared with control TG content values. Thus both plasma FFA and intramuscular TG are substrates for energy production during electrical stimulation. However, the stimulation parameters employed affect the quantities utilized.


Asunto(s)
Ácidos Grasos/metabolismo , Músculos/metabolismo , Animales , Estimulación Eléctrica , Ácidos Grasos no Esterificados/metabolismo , Glucosa/farmacología , Técnicas In Vitro , Insulina/farmacología , Masculino , Músculos/efectos de los fármacos , Ratas , Ratas Endogámicas , Triglicéridos/metabolismo
8.
J Appl Physiol (1985) ; 68(1): 348-54, 1990 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2312476

RESUMEN

The contribution of intracellular triacylglycerol (TG) as a substrate for skeletal muscle during electrical stimulation is equivocal. Therefore, the purpose of this study was to investigate the effect of electrical stimulation on the TG content in the isolated intact rat flexor digitorum brevis skeletal muscle preparation by use of two different stimulation protocols. Muscles were electrically stimulated for 1 h either continuously at 1 Hz or intermittently (30 s on, 60 s off) at 5 Hz while incubated in 21 degrees C Krebs bicarbonate buffer (pH 7.4) that contained 11 mM glucose. Control muscles were either frozen immediately after excision or incubated for 1 h. TG content was significantly decreased (P less than 0.05) compared with control concentrations in both stimulated muscle groups, with the greatest reduction (60%) occurring after 5-Hz intermittent stimulation. These data indicate that intramuscular TG is hydrolyzed in response to electrical stimulation in the isolated flexor digitorum brevis muscle preparation. In addition, the type of stimulation (higher frequency intermittent vs. lower frequency continuous) employed influences the amount of intracellular TG hydrolyzed.


Asunto(s)
Músculos/metabolismo , Triglicéridos/metabolismo , Animales , Estimulación Eléctrica , Técnicas In Vitro , Masculino , Músculos/análisis , Músculos/fisiología , Ratas , Ratas Endogámicas , Triglicéridos/análisis
9.
Clin J Pain ; 16(4): 340-4, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11153791

RESUMEN

OBJECTIVE: Patients with complex regional pain syndrome type I (CRPSD1) may have thermal allodynia after application of a non-noxious thermal stimulus to the affected limb. We measured the warm, cold, heat-evoked pain threshold and the cold-evoked pain threshold in the affected area of 16 control patients and patients with complex regional pain syndrome type 1/RSD to test the hypothesis that allodynia results from an abnormality in sensory physiology. SETTING: A contact thermode was used to apply a constant 1 degrees C/second increasing (warm and heat-evoked pain) or decreasing (cold and cold-evoked pain) thermal stimulus until the patient pressed the response button to show that a temperature change was felt by the patient. Student t test was used to compare thresholds in patients and control patients. RESULTS: The cold-evoked pain threshold in patients with CRPSD1/RSD (p <0.001) was significantly decreased when compared with the thresholds in control patients (i.e., a smaller decrease in temperature was necessary to elicit cold-pain in patients with CRPSD1/RSD than in control patients). The heat-evoked pain threshold in patients with CRPS1/RSD was (p <0.05) decreased significantly when compared with thresholds in control patients. The warm- and cold-detection thresholds in patients with CRPS1/RSD were similar to the thresholds in control patients. CONCLUSIONS: This study suggests that thermal allodynia in patients with CRPS1/RSD results from decreased cold-evoked and heat-evoked pain thresholds. The thermal pain thresholds are reset (decreased) so that non-noxious thermal stimuli are perceived to be pain (allodynia).


Asunto(s)
Hiperalgesia/fisiopatología , Neuronas Aferentes/fisiología , Umbral del Dolor/fisiología , Distrofia Simpática Refleja/fisiopatología , Adulto , Frío , Femenino , Calor , Humanos , Hiperalgesia/etiología , Masculino , Persona de Mediana Edad , Estimulación Física , Distrofia Simpática Refleja/etiología
10.
J Chromatogr A ; 864(2): 247-56, 1999 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-10669292

RESUMEN

A natural 19-amino-acid poly-histidine affinity tag was cloned at the N-terminus of three recombinant proteins. The vectors containing the DNA of the fusion proteins were used for transformation of Escherichia coli DH5alpha cells. Each protein was expressed, extracted and purified in one chromatographic step. The purification procedure for each protein can be accomplished in less than 1 h. A new type of immobilized metal ion affinity chromatography adsorbent--Co2+-carboxymethylaspartate agarose Superflow--was utilized at linear flow-rates as high as 5 cm/min. The final preparation of each protein is with purity greater than 95% as ascertained by sodium dodecyl sulfate-electrophoresis. Recovery for each purified protein was higher than 77% of the initial loaded amount as judged by biological activity. The operational capacity of Co2+-carboxymethylaspartate agarose for each protein was determined.


Asunto(s)
Marcadores de Afinidad/química , Ácido Aspártico/análogos & derivados , Histidina , Péptidos/química , Proteínas Recombinantes/aislamiento & purificación , Sefarosa/análogos & derivados , Sefarosa/química , Secuencia de Aminoácidos , Ácido Aspártico/química , Secuencia de Bases , Cloranfenicol O-Acetiltransferasa/química , Cromatografía de Afinidad , Clonación Molecular , Reactivos de Enlaces Cruzados , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , ADN Bacteriano/metabolismo , Electroforesis en Gel de Poliacrilamida , Escherichia coli/genética , Escherichia coli/metabolismo , Vectores Genéticos , Proteínas Fluorescentes Verdes , Proteínas Luminiscentes/química , Datos de Secuencia Molecular , Desnaturalización Proteica , Proteínas Recombinantes/química , Tetrahidrofolato Deshidrogenasa/química
11.
Am J Health Promot ; 7(4): 270-80, 295, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-10146850

RESUMEN

PURPOSE: The purpose of this review is to determine whether incentive-based programs conducted at worksites increase participation and long-term smoking cessation rates. METHODS: Published studies of workplace smoking cessation programs involving incentives and competition were identified through all available years up to winter of 1992 in MEDLINE (1966-1992), Psychlit (1967-1992), Smoking and Health (1960-1992), and Combined Health Information (1973-1992) computer databases and article reference lists. Programs were considered incentive programs when they involved either cash or other prizes paid to the participant for quitting smoking. Incentive competition programs typically involve groups contesting for prizes by having the greatest smoking cessation rates. Thirty studies were found, out of which 15 quasi-experimental and experimental studies are reviewed. The 15 studies that did not have comparison groups were excluded from this report. RESULTS: Only eight studies had a comparison group in which the effects of incentives and competition were separated from the effects of other interventions. Only one study separated the effects of competition from incentives. Five of these studies evaluated smoking rates after six months, and three after 12 months from the program start. Three of these studies showed that incentives increased participation rates, and five enhanced smoking reduction. No study showed, however, that incentives and/or competition enhanced smoking cessation past six months. CONCLUSIONS: It appears that incentives/competition may be useful for increasing participation and smoking reduction. Further research needs to be conducted to determine whether incentives and/or competition enhance long-term quit rates, and what are the most effective types of incentive procedures.


Asunto(s)
Promoción de la Salud/métodos , Motivación , Servicios de Salud del Trabajador/métodos , Salud Laboral , Cese del Hábito de Fumar , Estudios de Seguimiento , Predicción , Humanos , Servicios de Salud del Trabajador/tendencias , Evaluación de Programas y Proyectos de Salud
12.
Am J Health Promot ; 13(2): 105-11, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-10346656

RESUMEN

PURPOSE: To determine the effectiveness of a multicomponent smoking cessation program supplemented by incentives and team competition. DESIGN: A quasi-experimental design was employed to compare the effectiveness of three different smoking cessation programs, each assigned to separate worksite. SETTING: The study was conducted from 1990 to 1991 at three aerospace industry worksites in California. SUBJECTS: All employees who were current, regular tobacco users were eligible to participate in the program offered at their site. INTERVENTION: The multicomponent program included a self-help package, telephone counseling, and other elements. The incentive-competition program included the multicomponent program plus cash incentives and team competition for the first 5 months of the program. The traditional program offered a standard smoking cessation program. MEASURES: Self-reported questionnaires and carbon monoxide tests of tobacco use or abstinence were used over a 12-month period. RESULTS: The incentive-competition program had an abstinence rate of 41% at 6 months (n = 68), which was significantly better than the multicomponent program (23%, n = 81) or the traditional program (8%, n = 36). At 12 months, the quit rates for the incentive and multicomponent-programs were statistically indistinguishable (37% vs. 30%), but remained higher than the traditional program (11%). Chi-square tests, t-tests, and logistic regression were used to compare smoking abstinence across the three programs. CONCLUSIONS: Offering a multicomponent program with telephone counseling may be just as effective for long-term smoking cessation as such a program plus incentives and competition, and more effective than a traditional program.


Asunto(s)
Conducta Competitiva , Promoción de la Salud , Motivación , Cese del Hábito de Fumar/estadística & datos numéricos , Lugar de Trabajo , Adulto , California , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Régimen de Recompensa , Resultado del Tratamiento
13.
Phys Ther ; 73(6): 361-73, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8497511

RESUMEN

As humans age, there is a decrease in the ability of skeletal muscle to generate force. This review describes alterations in the neuromuscular systems of humans and animals that may be responsible for the diminished force-generating capacity of older muscles. The effects of resistance training on the force-generating capacity of older muscles in humans and on the neuromuscular systems of humans and animals are then examined. The age-related decline in force-generating capacity may be due, in part, to a loss of motor units and to a decline in muscle mass. Fiber atrophy and, possibly, loss of muscle fibers contribute to the decline in muscle mass in older persons. High-intensity resistance training appears to attenuate the age-related decline in force-generating capacity in humans and cause fiber hypertrophy of old muscle fibers. Investigations of the effects of age on the neuromuscular system and of the effects of resistance training on the neuromuscular system and the functional capacity of older persons are essential for the development of cost-effective interventions that will increase the physical capacity of older persons.


Asunto(s)
Envejecimiento/fisiología , Músculos/fisiología , Educación y Entrenamiento Físico , Animales , Femenino , Humanos , Masculino , Ratas , Valores de Referencia
14.
Phys Ther ; 76(3): 260-7, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8602411

RESUMEN

BACKGROUND AND PURPOSE: During brief, high-intensity activities, skeletal muscle adenosine triphosphate (ATP) is rapidly resynthesized. Little is known, however, about the effect of age on ATP synthesis during such activities. In this study, aged muscle anaerobic metabolism during supramaximal, intermittent electrical stimulation was investigated. SUBJECTS: The flexor digitorum brevis (FDB) muscles from virgin 12-month-old (adult) and 32-month-old (aged) F1 hybrid Fisher 344 X Norway Brown male rats (12 rats per age group) were studied. There were three experimental groups (eight muscles per experimental group): control (no incubation or electrical stimulation), incubation (no electrical stimulation), and electrical stimulation (combined with incubation). METHODS: Incubation and electrical stimulation muscles were incubated in vitro in physiological medium for 15 minutes. Electrical stimulation muscles were stimulated intermittently, 10 seconds on:20 seconds off, using direct-current monophasic waveforms (intensity=80 V, pulse duration=200 milliseconds, and frequency=5.0 Hz). Muscle peak tension was measured, and intracellular ATP, creatine phosphate, glycogen, and lactate concentrations were determined. RESULTS: The ATP, creatine phosphate, and glycogen contents in adult and aged muscles were similar in control preparations. There were also no age-related differences in the muscles' utilization of intramuscular ATP and creatine phosphate during stimulation. A greater depletion of glycogen and accumulation of lactate occurred, however, in the aged muscles compared with the adult muscles during stimulation. CONCLUSION AND DISCUSSION: Aged rat FDB muscle appears to retain its capacity to rapidly resynthesize ATP through anaerobic metabolism during brief, high-intensity activity. Inadequate anaerobic resynthesis of ATP does not appear to contribute to the earlier and greater decline in peak train tension in the aged muscle.


Asunto(s)
Envejecimiento/fisiología , Glucólisis , Músculo Esquelético/metabolismo , Adenosina Trifosfato/biosíntesis , Anaerobiosis , Animales , Estimulación Eléctrica , Masculino , Ratas , Ratas Endogámicas F344
15.
Respir Care ; 28(11): 1456-61, 1983 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10315478

RESUMEN

The health professional needs to make an educational diagnosis before he selects a specific approach to patient education. Tailoring a patient education program to the patient's belief regarding his health and the patient's expectations regarding his diagnosis and care is useful. Other factors that influence the pulmonary rehabilitation team's selection of educational methodology are the patient's age, sex, educational level, cultural background, and prior experience with his disease. An educational program oriented to patients who rely on self-motivation or self-reward should provide choice of treatment, involvement of the patient in making choices, information-giving, and strong emphasis on individual responsibility. An educational program oriented to patients who demonstrate success when group strategies and support are used should encourage them to believe that their health can be controlled, even if it is dependent upon powerful others. Values clarification and behavior modification are also helpful in patient education.


Asunto(s)
Actitud Frente a la Salud , Enfermedades Pulmonares Obstructivas/rehabilitación , Educación del Paciente como Asunto/métodos , Factores de Edad , California , Escolaridad , Hospitales con más de 500 Camas , Humanos , Control Interno-Externo , Cooperación del Paciente , Factores Sexuales
16.
Addict Behav ; 19(3): 229-56, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7942243

RESUMEN

There is a strong, significant relationship between coffee consumption and smoking. In six epidemiological studies reviewed and analyzed here, 86.4% of smokers consumed coffee versus 77.2% of nonsmokers. Exsmokers use more coffee than nonsmokers but somewhat less than smokers. Seventeen experimental studies suggest that the pharmacologic effect of caffeine in coffee may be partially but not totally responsible for the relationship. Conditioning, a reciprocal interaction (caffeine intake increases anxiety/arousal--nicotine decreases it), or joint effect of a third variable (e.g., stress, alcohol) may account for the relationship. In abstinent smokers, blood caffeine levels increase and remain elevated for as long as 6 months. These higher caffeine plasma levels may be sufficient to produce caffeine toxicity syndrome. A review of 86 studies of nicotine withdrawal, caffeine withdrawal, and caffeine toxicity suggests that the symptoms are similar enough to be confused, and that reported nicotine withdrawal symptoms may be a mixture of nicotine withdrawal and caffeine toxicity.


Asunto(s)
Cafeína , Nicotina/efectos adversos , Cese del Hábito de Fumar/psicología , Síndrome de Abstinencia a Sustancias/psicología , Trastornos Relacionados con Sustancias/psicología , Nivel de Alerta/efectos de los fármacos , Cafeína/efectos adversos , Interacciones Farmacológicas , Humanos , Síndrome de Abstinencia a Sustancias/diagnóstico
17.
Addict Behav ; 22(1): 55-68, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9022872

RESUMEN

Continuous caffeine consumption with smoking cessation has been associated with more than doubled caffeine plasma levels. Such concentrations may be sufficient to produce caffeine toxicity symptoms in smoking abstinence conditions. To test whether caffeine abstinence influences smoking cessation, 162 caffeine-using smokers were enlisted from American Lung Association smoking cessation programs. Volunteers were randomly assigned by clinic to caffeine-use and caffeine-abstinence conditions and measured for 3 weeks post-smoking cessation, at 6 months and one year. Results showed a significant linear increase in caffeine sputum levels across 3 weeks post cessation for those who quit smoking and continued using caffeine. Three weeks after cessation, concentrations reached 203% of baseline for the caffeine user. Typical nicotine withdrawal symptoms occurred during the first 16 days of cessation. The caffeine abstainers, but not continued users of caffeine, reported increased fatigue during the first 3 days of cessation. Among complete caffeine abstainers, compared with caffeine users, there was a significant increase in fatigue, a decrease in stimulation, and a marginal increase in caffeine craving immediately following tobacco cessation. There were no differences between the groups on other withdrawal symptoms or in cessation success at 16 days, 6 months, or 12 months.


Asunto(s)
Cafeína/farmacología , Nicotina , Cese del Hábito de Fumar , Síndrome de Abstinencia a Sustancias/complicaciones , Síndrome de Abstinencia a Sustancias/fisiopatología , Análisis de Varianza , Cafeína/análisis , Fatiga/etiología , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Nicotina/análisis , Análisis de Regresión , Saliva/química , Análisis de Supervivencia , Factores de Tiempo
18.
J Sch Health ; 60(7): 379-82, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2246880

RESUMEN

The scope and content of school health education research conducted from 1984-1987 in countries outside the U.S. are examined. Both published and unpublished research were requested from sources identified by the American School Health Association's Council on International Health. One hundred eighty-eight studies from 31 countries were reviewed and categorized. Countries that publish journals devoted to school health offer more opportunities for publishing research. Analysis of the studies revealed that individuals involved in school health face similar problems regardless of country. Cross-country comparative studies serve as models for future research.


Asunto(s)
Investigación sobre Servicios de Salud/tendencias , Cooperación Internacional , Servicios de Salud Escolar/normas , Política de Salud , Humanos , Prevalencia , Fumar/epidemiología
19.
J Sch Health ; 68(4): 141-5, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9644606

RESUMEN

In 1995, a survey was conducted among students attending 69 Seventh-day Adventist (SDA) high schools within the United States and Canada. The survey assessed the extent that these students practiced sexual and drug-use behaviors which place them at risk for contracting or transmitting the human immunodeficiency virus (HIV). A total of 1,748 respondents enrolled in grades 9 through 12 completed questionnaires similar to the instrument used in the 1993 Youth Risk Behavior Survey (YRBS). Data were collected and compared to results from the 1993 YRBS. Students who attended SDA parochial schools reported lower rates of sexual intercourse compared to YRBS school counterparts (16.3% vs. 53.1%) and lower rates of all substances measured. Furthermore, respondents were more likely to engage in substance use and sexual intercourse if they had at least one parent who used tobacco, alcohol, or marijuana, as reported by the students.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Conocimientos, Actitudes y Práctica en Salud , Adolescente , Canadá , Distribución de Chi-Cuadrado , Femenino , Humanos , Masculino , Relaciones Padres-Hijo , Factores de Riesgo , Conducta Sexual/estadística & datos numéricos , Trastornos Relacionados con Sustancias/enzimología , Encuestas y Cuestionarios , Estados Unidos
20.
J Hum Hypertens ; 25(5): 311-9, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-20555357

RESUMEN

The effect of one single bout of aerobic exercise on the vascular and baroreceptor function of individuals with a family history of hypertension was investigated. Forty young males, mean age 21 years, comprising offspring with (FH(+); n=20) and without (FH(-); n=20) a family history of hypertension participated in this study. Acute exercise was performed on a stationary bike for 20 min at 60% of maximal oxygen uptake. Peak forearm blood flow (FBF) was assessed using plethysmography and was determined as the highest blood flow after 5 min of reactive hyperaemia. Cardiopulmonary baroreceptor (CPBR) sensitivity was measured using lower-body negative pressure (LBNP) for 5 min at -20 mm Hg. CPBR was determined by calculating change of stroke volume and forearm vascular resistance (FVR) at baseline and during LBNP. Carotid baroreceptor (CBR) sensitivity was assessed using neck suction at -20, -40, -60 and -80 mm Hg pressures and was determined from RR interval divided by systolic blood pressure. Augmentation index (AIx), a measure of wave reflection, was assessed using applanation tonometry, and was calculated as the ratio of augmented pressure and pulse pressure. The peak FBF at pre-exercise was lower in FH(+) than in FH(-) subjects. Twenty minutes of acute cycle exercise resulted in significantly increased peak FBF by 22% in FH(+) and by 11% in FH(-) subjects, whereas peak FVR of both groups decreased by 17% and 11%, respectively. No change occurred in CPBR, CBR or AIx. It is concluded that 20 min of acute cycle exercise normalised baseline FBF and forearm vasodilation during hyperaemia in FH(+) subjects.


Asunto(s)
Arterias/fisiología , Barorreflejo/fisiología , Ejercicio Físico , Hipertensión/genética , Adolescente , Adulto , Antebrazo/irrigación sanguínea , Humanos , Hipertensión/fisiopatología , Presión Negativa de la Región Corporal Inferior , Masculino , Flujo Sanguíneo Regional , Resistencia Vascular
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