Search PubMed⌕ Search

Biomedical subjects

M J Lentz

Publications and source records attributed to M J Lentz.

16 recordsLinked to original sources
PubMed1999

Effects of selective slow wave sleep disruption on musculoskeletal pain and fatigue in middle aged women.

OBJECTIVE: To determine whether disrupted slow wave sleep (SWS) would evoke musculoskeletal pain, fatigue, and an alpha electroencephalograph (EEG) sleep pattern. We selectively deprived 12 healthy, middle aged, sedentary women without muscle discomfort of SWS for 3 consecutive nights. Effects were assessed for the following measures: polysomnographic sleep, musculoskeletal tender point pain threshold, skinfold tenderness, reactive hyperemia (inflammatory flare response), somatic symptoms, and mood state. METHODS: Sleep was recorded and scored using standard methods. On selective SWS deprivation (SWSD) nights, when delta waves (indicative of SWS) were detected on EEG, a computer generated tone (maximum 85 decibels) was delivered until delta waves disappeared. Musculoskeletal tender points were measured by dolorimetry; skinfold tenderness was assessed by skin roll procedure; and reactive hyperemia was assessed with a cotton swab test. Subjects completed questionnaires on bodily feelings, symptoms, and mood. RESULTS: On each SWSD night, SWS was decreased significantly with minimal alterations in total sleep time, sleep efficiency, and other sleep stages. Subjects showed a 24% decrease in musculoskeletal pain threshold after the third SWSD night. They also reported increased discomfort, tiredness, fatigue, and reduced vigor. The flare response (area of vasodilatation) in skin was greater than baseline after the first, and again, after the third SWSD night. However, the automated program for SWSD did not evoke an alpha EEG sleep pattern. CONCLUSION: Disrupting SWS, without reducing total sleep or sleep efficiency, for several consecutive nights is associated with decreased pain threshold, increased discomfort, fatigue, and the inflammatory flare response in skin. These results suggest that disrupted sleep is probably an important factor in the pathophysiology of symptoms in fibromyalgia.

Adult↗
PubMed1998

Luteal phase ovarian steroids, stress arousal, premenses perceived stress, and premenstrual symptoms.

The purpose of this study was to examine the relationships among perceived stress, ovarian steroids (estradiol and pregnanediol), stress arousal indicators (cortisol, catecholamines) and premenstrual symptoms (turmoil, fluid retention). Women (N = 74) with low symptom severity (LS), premenstrual syndrome (PMS), or premenstrual magnification (PMM) symptom patterns provided daily urine samples over one cycle and recorded their symptoms and perceived stress levels in a health diary. Multiple regression analysis was used to test models of premenstrual symptoms in separate analyses for women with the LS and PMS symptom patterns and the LS and PMM symptom patterns. Data from the LS and PMS groups revealed that greater stress ratings accounted for turmoil symptoms and higher luteal phase cortisol levels for fluid retention symptoms. For LS and PMM groups, lower luteal phase norepinephrine levels, higher global stress ratings, and a more gradual drop in estradiol premenses accounted for turmoil symptoms. Premenses norepinephrine and epinephrine levels and premenses stress ratings accounted for fluid retention. These findings support an important relationship among perceived stress, stress arousal indicators, and premenstrual symptoms that differs for women with a PMS and PMM symptom pattern.

Adult↗
PubMed1998

Perceived stress, physiologic stress arousal, and premenstrual symptoms: group differences and intra-individual patterns.

The purpose of this study was to examine evidence for perceived stress, hypothalamic-pituitary-adrenal, and autonomic nervous system involvement in premenstrual symptoms. Women with a low severity (LS, n = 40), premenstrual syndrome (PMS, n = 22), and premenstrual magnification symptom patterns (PMM, n = 26) rated perceived stress, turmoil, and fluid retention symptoms for one entire cycle. Daily late afternoon urine samples were assayed for epinephrine, norepinephrine, and cortisol. Using multivariate analysis of variance analyses, we found significant group and cycle phase and group by phase interaction effects for perceived stress. There were no group or cycle phase differences in cortisol, epinephrine, and norepinephrine. Intraindividual analyses using cross-correlation techniques revealed a positive time lagged relationship between perceived stress and norepinephrine and cortisol levels across all groups. Only women with a PMS pattern demonstrated perceived stress leading epinephrine levels. Cortisol, epinephrine, and norepinephrine levels led symptoms for all groups with one exception: there was no cross-correlation between epinephrine and turmoil for the PMS group. Perceived stress led both types of symptoms, regardless of group, and symptoms also led stress. The results provide evidence for a unique relationship between epinephrine, perceived stress, and symptoms for women with PMS, and for a reciprocal relationship between stress and symptoms for each of the groups.

Adult↗
PubMed1998

Sleep deprivation alters body temperature dynamics to mild cooling and heating not sweating threshold in women.

Sleep deprivation alters thermoregulatory responses. We used control of skin temperature to produce mild thermal challenge, both cool (32 degrees C) and warm (38 degrees C), and recorded esophageal and rectal temperatures, sweat rate and forearm blood flow in six healthy young women at rest. We discovered that after one night of sleep deprivation (1) both mean esophageal and rectal temperatures were reduced, (2) the mean threshold for sweating was not altered, and (3) there was no direct indication that skin blood flow was set at different levels with skin temperature neutral or cool. Peripheral vasodilation was attenuated when skin temperature was held at 38 degrees C. Following this period of mild hyperthermia, esophageal and rectal temperatures decreased much more rapidly in sleep-deprived subjects when skin temperature was cooled and held constant at 32 degrees C. We conclude that sleep-deprived women lose heat rapidly in response to a mild cooling stimulus. Sleep-deprived humans may be more vulnerable to heat loss with reduced ability to warm even at temperatures thought to be associated with thermal comfort.

Adult↗
PubMed1995

Social pathways to premenstrual symptoms.

The purpose of this study was to explore feminine and menstrual socialization, expectations about experiencing symptoms, and the stressful nature of women's lives among women with three perimenstrual symptom patterns. Social learning and stress theory provided a theoretical framework for understanding why some menstruating women experience premenstrual syndrome or premenstrual magnification symptom patterns. Data about socialization, stressful life context, expectations about symptoms, depressed mood, and other health-related and demographic indicators were obtained from an interview. Subsequent daily recordings in a health diary for two or more menstrual cycles provided data with which to classify women's symptoms across the menstrual cycle as a low severity symptom (LS, n = 73), premenstrual syndrome (PMS, n = 36), or premenstrual magnification (PMM, n = 62) pattern. Stepwise discriminant function analysis demonstrated that stressful life context, menstrual socialization, and expectations about symptoms related to menstruation differentiated women with an LS from those with a PMS or PMM symptom pattern. In addition, depressed mood differentiated the three groups.

Adult↗
PubMed1994

Arousal and stress response across the menstrual cycle in women with three perimenstrual symptom patterns.

The purpose of this study was to compare arousal levels and stress response across menstrual cycle phases in women with three perimenstrual symptom patterns. Women with low symptom severity (LS, N = 28), were compared with those with a premenstrual syndrome (PMS, N = 15) and premenstrual magnification (PMM, N = 19) pattern across postmenses and premenses phases. Each woman was assessed during relaxation and in response to mental task and symptom imaging stressors during a postmenses and premenses day. Results of baseline skin conductance (SCL), electromyogram (EMG), and finger temperature (T) demonstrated arousal premenses in women with the PMS pattern, but not in women with the LS pattern. In addition, women with the PMS pattern experienced increased EMG and SCL response to stressors premenses. Women with the PMM pattern experienced a rise in finger temperature premenses, opposite the pattern of the women with LS or PMS. These results support development of symptom management strategies to reduce arousal and modulate stress response for women with PMS who seek help for their symptoms. In addition, the difference in arousal and stress response observed in women with PMS and PMM support development of different symptom management strategies for these two groups of women.

Adolescent↗
PubMed1994

Fatigue as a response to environmental demands in women's lives.

Fatigue is a significant health care problem of interest to professionals in many disciplines. Yet, it is poorly understood. Fatigue, as an indicator of adaptation, is examined in relationship to internal and external environmental demands in women's lives. From a secondary analysis of data collected from a large group of women in a Northwest urban community in the U.S., it was found that internal demands such as depression or anxiety are more significantly related to fatigue and vitality than external demands such as negative life events or employment status.

Adolescent↗
PubMed1993

Behavioral responses of Escherichia coli to changes in temperature caused by electric shock.

The behavioral response of Escherichia coli to electric shock in 10(-2) M potassium phosphate plus 10(-4) M potassium EDTA was studied. When presented with a 150-V/cm electric shock that lasted 250 ms, the bacteria at first exclusively ran, then exclusively tumbled, and finally returned to their original running and tumbling. This response is due to increased temperature caused by the electric shock, i.e., to thermotaxis, and it is mediated by the chemotaxis machinery. A more severe electric shock, 150 V/cm for 550 ms, caused cells to tumble immediately, and then they went back to their original running and tumbling. The mechanism of that response is unknown since, unlike known thermotaxis, it does not require the chemotaxis machinery.

Chemotaxis↗
PubMed1990

Time-series analysis--cosinor analysis: a special case.

Cosinor analysis provides an accessible means of evaluating and estimating the parameter of a cyclic phenomenon. Cosinor analysis does not require that the data be equal intervals without missing data. Cosinor analysis does require that the data can reasonably be considered to take the form of a deterministic cycle with a known period.

Humans↗
PubMed1989

Circadian rhythms: charting oral temperatures to spot abnormalities.

1. A normal daily variation in body temperature is found in the elderly. Normal oral temperature in an older person is lower than in a younger person, and the temperature peaks in the early afternoon and is lowest in the early morning hours before awakening. 2. Elderly subjects may be more prone to hypothermia in the early morning hours when their body temperature is naturally lower. Bathing may cause the body temperature to drop up to 1 degree C and add to this risk. 3. Many factors should be considered when analyzing temperature data for the determination of fever. Time of day, as well as symptoms of infection, should be considered. 4. Disturbances in circadian temperature rhythms accompany central nervous system dysfunction and may be an early indicator of other illnesses.

Aged↗
PubMed1988

Being healthy: women's images.

Although the concept of health is central to nursing practice and science, measurement of the concept has lagged far behind theory development. The study presented extends Laffrey's earlier work by describing the meaning of health for a population of women representing multiple ethnic groups residing in the Pacific Northwest. A sample of 528 women from a cross-section of a community who had participated in a study of women's health was asked to respond to the question, "What does being healthy mean to you?" In addition to evidence of the clinical, role performance, and adaptive models of health, the women's responses yielded nine dimensions consistent with the eudaemonistic model. Each dimension included multiple descriptors identified through content analysis of the women's verbatim responses. The women's images of health were consistent with Smith's and Laffrey's four conceptions, but the eudaemonistic category included multiple dimensions. The women reported images of health consistent with contemporary nursing theorists' views. Moreover, their emphasis on eudaemonistic images crossed all categories of age, education, income, ethnicity, and employment status.

Adolescent↗
PubMedDate not supplied

Self-report and polysomnographic measures of sleep in women with irritable bowel syndrome.

BACKGROUND: Women who report chronic gastrointestinal symptoms compatible with a diagnosis of irritable bowel syndrome (IBS) frequently report sleep disturbances. OBJECTIVES: The purposes of this study were to (a) compare self-reported and polysomnographic indicators of sleep quality in women with IBS symptoms (IBS-SX, n= 16) and controls (n= 16); (b) examine the relationship between the indicators of sleep quality; and (c) determine the relationship between sleep indicators and psychological distress. METHOD: The women slept in a laboratory for 2 consecutive nights. Polysomnographic measurements were recorded during sleep, and a sleep questionnaire was completed upon awakening each morning. Psychological distress was measured with the Symptom Checklist-90-R during the initial interview. RESULTS: Women in the IBS-SX group reported significantly greater numbers of awakenings during sleep (p = .008) and had a longer latency to REM sleep (p = .04) than did the controls. Self-reported and polysomnographic indicators were more highly correlated in the control group than in the IBS-SX group. In the IBS-SX group, the greater the psychological distress, the less alert (rs = .419) and rested (rs = .564) the women felt in the morning and the more time the women spent in stages 3 and 4 sleep (rs = .479) and less in stage 2 (rs = -.447) and REM (rs = -.414) sleep. In the control group, psychological distress was not significantly associated with self-reported measures but was significantly associated with the number of awakenings (rs = .506) and time in stages 3 and 4 sleep (rs = -.677). CONCLUSIONS: Although the women in the IBS-SX group reported significantly more awakenings, the weak relationship between self-reported and polysomnographic indicators suggests that clinicians must keep in mind that further assessments may be necessary.

Adult↗
PubMedDate not supplied

Differentiation of women with three perimenstrual symptom patterns.

The purpose of this study was to differentiate women with three perimenstrual symptom severity patterns: premenstrual syndrome (PMS), premenstrual magnification (PMM), and low symptom (LS). Factors entered into the discriminant functions included social demands, personal resources, socialization, parity, age, personal health practices, and psychological distress. A community-based sample of 142 women taking no oral contraceptives was classified into one of the three symptom severity patterns. Three two-way discriminant analyses were performed. Women with PMS had more psychological distress, more education, and a mother with more premenstrual symptoms than those with an LS pattern. Women with PMM had more psychological distress and a mother with more premenstrual symptoms, but they also had more stress and were younger than those with an LS pattern. Finally, the women with PMS, when compared to the PMM subgroup, were older, had more education, engaged in more positive health practices, and had more nontraditional attitudes toward women. In addition, the women with PMM had more stress in their lives than women with PMS.

Adolescent↗