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1.
Med Oral Patol Oral Cir Bucal ; 26(3): e334-e340, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33340085

RESUMEN

BACKGROUND: Metallothioneins (MTs) gene polymorphisms have been associated with the ability of free radical scavenging and detoxification of heavy metals leading to cancer development. Our aim was to revisit, in a Brazilian population, single-nucleotide polymorphisms (SNPs) of the MT gene family previously associated with oral squamous cell carcinoma (OSCC). MATERIAL AND METHODS: A case-control investigation with 28 OSCC patients and 45 controls was conducted, using conventional risk factors (tobacco use and alcohol consumption) as covariates. SNPs genotyping for rs8052334 (MT1B), rs964372 (MT1B), and rs1610216 (MT2A) was performed by PCR-RFLP, and SNPs for rs11076161 (MT1A) were analyzed by TaqMan assay. RESULTS: The only SNP associated with increased risk for OSCC was the MT-1A AA genotype (OR = 4.7; p = 0.01). We have also evidenced for the first time a significant linkage disequilibrium between the SNPs of MT-2A and MT-1A in this population with the highest frequency (30%) of the unfavorable haplotype G/A/C/T (rs1610216 / rs11076161 / rs964372 / rs8052334) of MT gene polymorphisms (OR = 6.2; p = 0.04). Interestingly, after removing the effects of conventional risk factors, we have uncovered the significance of the AA genotype of the rs11076161 with increased odds of 19-fold higher towards OSCC development. CONCLUSIONS: This is the first demonstration that a significant linkage disequilibrium among gene polymorphisms of the MT family may affect susceptibility to oral cancer, which is conditioned by the G/A/C/T haplotype (rs1610216/rs11076161/rs964372/ rs8052334) and the MT-1A gene polymorphism has a potential clinical utility for the OSCC risk assessment.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Brasil , Carcinoma de Células Escamosas/genética , Estudios de Casos y Controles , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Metalotioneína/genética , Neoplasias de la Boca/genética , Polimorfismo de Nucleótido Simple , Factores de Riesgo , Carcinoma de Células Escamosas de Cabeza y Cuello
2.
Med Oral Patol Oral Cir Bucal ; 25(5): e616-e625, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32683391

RESUMEN

BACKGROUND: The aim of this study was to describe the relative frequency and the main demographic and clinic-radiographic features related to patients diagnosed with Simple bone cyst (SBC) in an Oral Diagnosis Service in Southeast Brazil and present a review and discussion of international literature on this topic. MATERIAL AND METHODS: SBC cases from our service encompassing the period between 1978 and 2017 were selected. In addition, a literature search was performed in the Pubmed/MEDLINE online electronic database published between 1951 and 2019. RESULTS: A total of 2,459 cystic lesions were documented in our service, thus 60 patients were diagnosed with the SBC representing 2.4% of all jaw cystic. Most of cases were asymptomatic. Multiple SBC lesions were seen in two patients (3.4%) and association with cemento-osseous dysplasia was seen in one female patient (1.7%). A total of 793 cases were enrolled in this literature review. CONCLUSIONS: The SBC is an asymptomatic lesion often discovered in routine image exams in young patients. The unilocular, well defined margin with scalloped appearance is characteristic and helps the definition of diagnosis. This review suggests a different epidemiologic trend concerning to the sex and it confirms the posterior region of mandible as the more frequent location. The conservative treatment with limited exploration and curettage remains as the gold-standard treatment.


Asunto(s)
Quistes Óseos , Tumores Odontogénicos , Brasil , Femenino , Humanos , Mandíbula , Instituciones Académicas
3.
Med Oral Patol Oral Cir Bucal ; 23(3): e262-e268, 2018 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-29680841

RESUMEN

BACKGROUND: Oral lichen planus (OLP) is a chronic inflammatory disease mediated by T cells, which manifests as reticular (white) or erosive (red) lesions, that are eventually painful. Oral lichenoid lesion (OLL) are distinguished from OLP by the presence of precipitating factors. The aim of this study was to evaluate whether the presence of metallothionein, which is involved in anti-apoptotic pathways and the anti-oxidative response, could serve as a differential diagnostic for OLP and OLL. MATERIAL AND METHODS: We evaluated the expression of metallothionein in 40 cases of OLP and 20 cases of OLL using immunohistochemistry. RESULTS AND CONCLUSIONS: White OLP has higher concentrations of metallothionein than red OLP in basal and parabasal layers. Moreover, metallothionein was more frequently observed in the cytoplasm and nuclei of basal cells in OLP patients compared to the same regions of OLL cases. Metallothionein levels are related to OLP severity and may contribute to a differential diagnosis between OLP and OLL.


Asunto(s)
Amalgama Dental , Liquen Plano Oral/diagnóstico , Liquen Plano Oral/metabolismo , Metalotioneína/biosíntesis , Adulto , Amalgama Dental/efectos adversos , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades de la Boca/diagnóstico , Enfermedades de la Boca/etiología , Enfermedades de la Boca/patología
4.
Philos Trans A Math Phys Eng Sci ; 366(1865): 579-89, 2008 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-17698463

RESUMEN

In this work, the possible chaotic nature of the atmospheric turbulence above a densely forested area in the Amazon region is investigated. To this end, we use high-resolution temperature data obtained during a micrometeorological measurement campaign in the Brazilian Amazonia. Estimates of the correlation dimension (D(2)=3.50+/-0.05) and of the largest Lyapunov exponent (lambda(1)=0.050+/-0.002) suggest the existence of chaos in the atmospheric boundary layer. Our findings indicate that this low-dimensional chaotic dynamics is associated with the presence of the coherent structures within the boundary layer right above the canopy top and not with the atmospheric turbulence per se, as previously claimed.


Asunto(s)
Movimientos del Aire , Árboles , Atmósfera , Fenómenos Biofísicos , Biofisica , Brasil , Conceptos Meteorológicos , Dinámicas no Lineales , Clima Tropical
5.
Phys Rev E Stat Nonlin Soft Matter Phys ; 65(3 Pt 2A): 035203, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11909146

RESUMEN

An investigation of interior crisis of high dimensions in an extended spatiotemporal system exemplified by the Kuramoto-Sivashinsky equation is reported. It is shown that unstable periodic orbits and their associated invariant manifolds in the Poincaré hyperplane can effectively characterize the global bifurcation dynamics of high-dimensional systems.

6.
Psychosom Med ; 62(4): 474-82, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10949091

RESUMEN

OBJECTIVE: Several behavioral, physiological, and subjective variables were examined in subjects reporting chronic insomnia (IN group) and subjects with no complaint of insomnia (NC group) to determine factors predictive of poor sleep as measured by electroencephalography (EEG sleep). METHODS: A total of 177 subjects (121 in the IN group and 56 in the NC group) were evaluated on the basis of EEG sleep, subjective sleep, sleepiness, performance, mood, personality, and metabolic parameters during a 36-hour laboratory stay. RESULTS: Equal percentages of subjects in each group had 0, 1, or 2 nights of poor EEG sleep, indicating that the IN group was not more likely to have impaired sleep in the laboratory. Results of the Minnesota Multiphasic Personality Inventory showed that subjects in the IN group had more pathological personality profiles, and results of laboratory studies showed that these subjects had worse mood ratings, less subjective sleepiness, poorer memory performance, and longer midafternoon sleep latencies. Subjects in the IN group also rated their laboratory sleep as poorer in quality with more time awake after sleep onset and longer sleep latencies, but no differences in EEG sleep were observed. Poor nights of EEG sleep were associated with being male, increasing age, and a history of more time awake after sleep onset; among the laboratory tests, poor EEG sleep was associated with worse mood ratings, poorer memory performance, longer sleep latencies (as indicated by higher scores on the Multiple Sleep Latency Test), higher sleep/wake ratios for metabolic parameters, lower ratings of sleep quality, and longer perceived sleep latencies. CONCLUSIONS: A history of chronic insomnia does not predict poor EEG sleep. Both chronic insomnia and poor EEG sleep are associated independently with dysphoria, hyperarousal, diminished waking function, and negative subjective sleep quality. Separate arousal and sleep systems are posited to account for these results.


Asunto(s)
Polisomnografía , Privación de Sueño/diagnóstico , Trastornos del Inicio y del Mantenimiento del Sueño/diagnóstico , Adolescente , Adulto , Afecto/fisiología , Atención/fisiología , Enfermedad Crónica , Metabolismo Energético/fisiología , Femenino , Humanos , MMPI , Masculino , Persona de Mediana Edad , Valores de Referencia , Privación de Sueño/fisiopatología , Privación de Sueño/psicología , Trastornos del Inicio y del Mantenimiento del Sueño/fisiopatología , Trastornos del Inicio y del Mantenimiento del Sueño/psicología , Fases del Sueño/fisiología , Vigilia/fisiología
7.
Hum Factors ; 40(1): 150-8, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9579109

RESUMEN

We tested the combined effects of work schedule and task factors on upper-extremity fatigue in the laboratory during 8-h and 12-h shift schedules. Participants performed a simulated manual assembly task at three repetition rates and three torque loads and self-adjusted their work cycle duration to maintain fatigue at moderate levels. Work cycle durations decreased with increases in both load level and repetition rate. Fatigue was observed more quickly with increasing time on shifts and during night shifts compared with day shifts. Work schedule effects were most apparent at lighter workloads, with minimal differences at higher workloads. The highest fatigue levels were observed during 12-h night shifts, with similar levels reached by the end of both the week of 8-h night shifts and the week of 12-h day shifts. Overall durations were 20%-30% shorter than in previous short-term studies, which was likely a result of the more realistic work schedules used in this study. Results from this study could be applied to the design of work-rest schedules for manual tasks involving the upper extremities.


Asunto(s)
Brazo , Fatiga/prevención & control , Admisión y Programación de Personal , Carga de Trabajo , Adulto , Análisis de Varianza , Femenino , Humanos , Masculino
8.
Occup Environ Med ; 53(10): 677-85, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8943832

RESUMEN

OBJECTIVE: To evaluate a new work schedule at a Finnish steel mill with special attention to effects on older workers. The schedule was designed to improve sleep before the morning shift, and alertness during the morning shift, by delaying shift start and end times. METHODS: Evaluation was by a shiftwork health and safety questionnaire, recordings of work-rest-sleep cycles with activity monitors worn on the wrist, daily diaries, and on site computerised testing of fatigue and alertness by the NIOSH fatigue test battery. RESULTS: The one hour delay in shift starting times improved sleep before the morning shift, and improved waking fatigue, sleepiness, and performance during the morning shift. Evening and night shift sleep and fatigue or sleepiness, however, were affected negatively by the new work schedule, but the results for those shifts were less consistent across the various measures. Despite the improvements, most workers were not satisfied with the new schedule because of social concerns. Few interactions of age with the new work schedule were found, suggesting that the effects of the work schedule were uniform across age groups. CONCLUSION: A change of as little as one hour in shift starting times can improve morning shift sleep and alertness, but there are trade offs from these improvements in terms of night shift effects and social considerations. It seems, then, that optimal shift start and end times for an entire organisation are difficult to institute on a wide scale. Tailoring shift schedules to subgroups within an organisation is suggested.


Asunto(s)
Fatiga/epidemiología , Metalurgia , Sueño/fisiología , Tolerancia al Trabajo Programado/psicología , Adulto , Factores de Edad , Ritmo Circadiano , Femenino , Humanos , Masculino , Persona de Mediana Edad
9.
Sleep ; 16(8): 727-35, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8165387

RESUMEN

Conditions surrounding self-selected napping and its association with waking function were examined in a quasi-experimental study at two worksites with workers on 8- and 12-hour rotating shifts. Nap frequency, sleep quantity, quality and timing were determined from daily questionnaires, and performance/alertness during the workshift was assessed with on-site computerized testing. Results indicated that most napping occurred prior to the first night shift of the week. Napping prior to the first shift supplemented an apparently adequate quantity of main sleep, whereas napping during the workweek compensated for a reduced quantity of main sleep. Sleep quality was rated higher on no-nap days than on nap days and higher prior to the first shift than during the workweek. These results generally support a compensatory view of napping. Worksite performance/alertness testing, however, indicated diminished alertness during the shift on nap days compared to no-nap days, which was not consistent with a compensatory view of napping. Decreased alertness on nap days may have been associated with poorer sleep quality or with differences in circadian rhythm adaptation on those days.


Asunto(s)
Sueño/fisiología , Vigilia/fisiología , Tolerancia al Trabajo Programado/fisiología , Adulto , Análisis de Varianza , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
10.
Hum Factors ; 35(4): 603-14, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7909308

RESUMEN

To date, research on the stress of sustained attention tasks has not explored the extent to which such stress is determined by the psychophysical aspects of the monitored display. In the present study, the effects of the sensory modality of signals (audition and vision) and the background event rate (5 and 40 events/min) on task-induced stress were examined in a vigilance situation. Critical signals for detection were slight changes in stimulus duration. Stress was indexed by motor restlessness and subjective reports of fatigue. Restlessness and subjective fatigue increased dramatically across a 50-min watch in all conditions. Stress effects were most notable in the case of visual monitoring but were unrelated to variations in event rate. Hence, from a psychophysical perspective, the stress of sustained attention seems to be identified more specifically with the sensory modality of signals than with the event rate context in which they appear.


Asunto(s)
Atención , Percepción Auditiva , Fatiga Mental/psicología , Reconocimiento Visual de Modelos , Agitación Psicomotora/psicología , Estrés Psicológico/complicaciones , Adolescente , Adulto , Femenino , Humanos , Masculino , Actividad Motora , Psicofísica
11.
Ergonomics ; 36(10): 1177-93, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8223409

RESUMEN

An 8 h/5-7 day shift schedule was compared with a newly instituted 12 h/2-4 day schedule in this, our second worksite study of extended workshifts. Workers completed a performance/alertness test battery, and a questionnaire on sleep patterns and other personal habits, 2-4 times a week on all shifts. After 10 months adaptation to the 12 h shift schedule, there were decrements in performance/alertness attributable to the extra 4 h on the extended shift. There were also reductions in sleep across the workweek which were most apparent on 12 h night shifts. The results are consistent with our first worksite study of 12 h shifts and indicate extra caution should be exercised when scheduling critical activities for extended workshifts, especially extended night shifts.


Asunto(s)
Nivel de Alerta , Atención , Ritmo Circadiano , Combustibles Fósiles , Tolerancia al Trabajo Programado , Adulto , Evaluación del Rendimiento de Empleados , Humanos , Masculino , Persona de Mediana Edad , Tiempo de Reacción
12.
J Gen Psychol ; 120(3): 323-37, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8138797

RESUMEN

A recent report by the National Research Council (Huey & Wickens, 1993) has identified transitions in task demand as an important dimension for study in vigilance research. This experiment tested the possibility that the effects of such transitions follow a relatively simple psychophysical rule--they are characterized by contrast effects. Transitions in task demand were achieved by shifting subjects from single-task to dual-task monitoring and vice versa. These transitions produced changes in subjects' sensing and decision-making functions that were far more intricate than simple contrast effects. The demand transition issue offers a complex research challenge on both basic and applied levels and warrants further investigation.


Asunto(s)
Atención , Adulto , Sensibilidad de Contraste , Toma de Decisiones , Femenino , Humanos , Masculino , Estimulación Luminosa , Análisis y Desempeño de Tareas
14.
Occup Med ; 5(2): 391-415, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2203163

RESUMEN

This chapter reviews a broad range of factors that, if controlled, might promote adaptation to nightwork, shiftwork, and extended workshifts. Systematic study has begun in four of the areas reported here: work schedule design, napping, bright light stimulation, and drugs. Physical activity, ambient temperature, diet, and individual behaviors have been studied only superficially.


Asunto(s)
Adaptación Fisiológica , Adaptación Psicológica , Ritmo Circadiano , Administración de Personal , Admisión y Programación de Personal , Tolerancia al Trabajo Programado , Trabajo , Ritmo Circadiano/fisiología , Humanos , Trabajo/fisiología , Trabajo/psicología , Tolerancia al Trabajo Programado/fisiología , Tolerancia al Trabajo Programado/psicología
15.
Occup Med ; 5(2): 315-22, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2203160

RESUMEN

Advantages and disadvantages of different work schedules--fixed days, fixed afternoons, fixed nights, and rotating shifts--are reviewed in terms of social satisfaction and adjustment for the worker and his or her family. The chapter also calls for new studies assessing the impact of changes in the complexion of the workforce and composition of the American family on shiftworker satisfaction.


Asunto(s)
Familia , Ajuste Social , Tolerancia al Trabajo Programado/psicología , Trabajo/psicología , Humanos
17.
Biol Psychol ; 25(2): 153-72, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3502753

RESUMEN

Many changes occur in sleep as a function of aging, but it is not known whether these changes result in sleep being less restorative. To examine the sleep restorative process, groups of 12 normal young adults and 12 normal and 12 insomniac male subjects, age 55-71, were totally sleep deprived for 64 hours and then allowed recovery sleep. Response speed, immediate recall, sleepiness, and body temperature were tested at approximately 2300, 0115, 0330, 0530 and 0800 during baseline, sleep loss, and recovery nights. Significant group (age or insomnia) by sleep loss condition interactions were found for reaction time and immediate recall performance measures. Similar significant interactions were found for oral temperature and all EEG sleep variables except total time in bed, percent stage 1, and percent REM. It was concluded that performance recovery following sleep loss was no slower in older subjects than in younger subjects despite very different recovery sleep stage parameters. This implied that aging effects on sleep are developmental rather than degenerative.


Asunto(s)
Envejecimiento/fisiología , Trastornos del Inicio y del Mantenimiento del Sueño/fisiopatología , Sueño/fisiología , Adolescente , Adulto , Anciano , Temperatura Corporal , Electroencefalografía , Humanos , Memoria , Persona de Mediana Edad , Tiempo de Reacción , Sueño REM
18.
Int J Neurosci ; 27(1-2): 73-83, 1985 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-4019064

RESUMEN

Attempts to demonstrate sleep stage effects on waking behavior have been equivocal at best. The present study provided a more sensitive approach to this problem by assessing performance and subjective alertness at repeated awakenings across baseline sleep and across recovery sleep following 40 and 64 hours of sleep deprivation. These behaviors were then compared to changes in EEG sleep, body temperature, and auditory threshold within these nights. Comparison of means between baseline and recovery sleep indicated that the behavioral variables were generally more sensitive than sleep stages to different amounts of prior wakefulness. Multiple regression analyses revealed no consistent covariation between behavior and any sleep stage which was independent of the correlations among the sleep stages themselves. Thus, distinct functions for specific sleep stages were not apparent from the comparison of means or the regression analyses. However, significant positive covariations were obtained between body temperature and performance, and auditory threshold and sleepiness. Significant negative covariations were obtained between body temperature and sleepiness, and auditory threshold and performance. From these results it was concluded that the most reliable predictors of behavior upon awakening were: the amount of wakefulness prior to sleep, the total amount of accrued sleep, circadian time as indexed by body temperature, and depth of sleep.


Asunto(s)
Memoria/fisiología , Recuerdo Mental/fisiología , Tiempo de Reacción/fisiología , Sueño/fisiología , Adolescente , Adulto , Nivel de Alerta , Umbral Auditivo , Temperatura Corporal , Ritmo Circadiano , Electroencefalografía , Humanos , Masculino , Privación de Sueño/fisiología , Fases del Sueño/fisiología
20.
Biol Psychol ; 16(1-2): 119-26, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6850022

RESUMEN

The present study provided polysomnographic corroboration of the frequently reported relationship between anxiety and subjective sleep disturbance. When compared to normals, anxious individuals were found to have significantly less sleep period time, total sleep time, percent stage REM and percent stage 4; shorter latency to stage REM; and greater percent stage 1. Partial correlations (holding depression constant) showed significant positive relationships between anxiety rating and number of awakenings, latency to stage 1, and percent stage 2. A significant negative relationship was found between anxiety and percent stage 4, and a nonsignificant negative trend was found between anxiety and latency to stage REM. Overall there was a tendency toward less sleep and lighter sleep in subjects with anxiety, thus validating subjective reports. The decreased latency to stage REM and its negative relation to anxiety, raised the possibility that this variable may not be specifically indicative of depression.


Asunto(s)
Ansiedad/psicología , Fases del Sueño , Adolescente , Adulto , Electroencefalografía , Femenino , Humanos , Masculino , Tiempo de Reacción , Sueño REM , Vigilia
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