Showing papers on "Morning published in 1994"

Morning bright light therapy for sleep and behavior disorders in elderly patients with dementia

Abstract: Fourteen inpatients with dementia showing sleep and behavior disorders (average age = 75 years), and 10 control elderly people (average age = 75 years) were carefully observed for 2 months. Four weeks of morning light therapy markedly improved sleep and behavior disorders in the dementia group. The measurement of sleep time and the serum melatonin values suggests that sleep and behavior disorders in the dementia group are related to decreases in the amplitude of the sleep-wake rhythm and decreases in the levels of melatonin secretions. Morning light therapy significantly increased total and nocturnal sleep time and significantly decreased daytime sleep time. These results indicate that morning bright light is a powerful synchronizer that can normalize disturbed sleep and substantially reduce the frequency of behavior disorders in elderly people with dementia.

Insulin levels, blood pressure and sleep apnea.

Abstract: This report concerns the relative contributions of body weight and sleep apnea to the following cardiovascular risk factors: blood pressure, fasting insulin and fasting glucose. We cross-sectionally examined the relationship of various levels of apneic activity [apnea-hypopnea index (AHI)] and a measure of obesity [body mass index (BMI)] to mean morning blood pressure and fasting serum insulin and fasting blood glucose concentrations sampled the morning after polysomnography. Subjects were 261 males (age 47 +/- 13 years, mean +/- SD), who were referred to a sleep laboratory for symptoms of sleep-disordered breathing. The dependent variables, mean morning blood pressure, insulin and fasting blood glucose (FBG) levels, were significantly related to both AHI (eta'2 = 0.10) and BMI (eta'2 = 0.18). AHI and BMI combined to account for approximately 30% of the variability in the best linear combination of these three factors. Further analysis indicated that mean morning blood pressure and fasting insulin levels each correlated positively with BMI and AHI, whereas FBG correlated only with BMI. We conclude that, although these data do not prove a causal relationship, there is evidence for an independent association between sleep apnea and not only blood pressure, but also fasting insulin levels.

Roles of type I and II corticosteroid receptors in regulation of basal activity in the hypothalamo-pituitary-adrenal axis during the diurnal trough and the peak : evidence for a nonadditive effect of combined receptor occupation

Abstract: Negative feedback regulation of basal activity in the hypothalamo-pituitary-adrenal (HPA) axis requires less corticosterone (B) at the trough (morning) than at the peak (evening) of the diurnal rhythm. It has been hypothesized that in the morning in rats, occupation of the high affinity, type I corticosteroid receptors is sufficient to inhibit adrenalectomy (ADX)-induced increases in plasma ACTH secretion, whereas in the evening, regulation occurs through the occupation of the lower affinity type II corticosteroid receptors. To examine this hypothesis, the sensitivity of ACTH to inhibition by two different doses of B or of dexamethasone (DEX) were compared in ADX rats killed in the morning or the evening (B has a higher affinity for type I receptors in vitro and in vivo; in vivo, DEX has a higher affinity for type II receptors). The requirement for greater concentrations of corticosteroids to inhibit ACTH secretion in the evening was verified. The effect of these treatments on the number of neurons immuno...

Seasonal Change of the Diurnal Cycle of Precipitation over Japan and Malaysia

Abstract: The diurnal cycle of precipitation is investigated using ground-based hourly observations for more than 10 years both in Japan and Malaysia. The diurnal cycle of precipitation in Japan is classified into three clusters. The first one has a peak in the morning, and the stations categorized into this cluster are located in coastal regions. The second cluster has two peaks in the morning and in the evening. These stations are located in an inland region. The morning peak in the above two clusters is dominant in June, when it is “baiu” in Japan. Baiu is the rainy season related to the southwest Asian monsoon. The third cluster is an exceptional case. No morning peak is observed in the stations of the third cluster and they have a comparatively strong evening peak. In the case of the Malay Peninsula, the inland region has a pronounced peak of rainfall at 1600 LST; the magnitude exceeds the mean of each month by 200%. This evening peak is too sharp to be represented by a 24-h-cycle sine wave decomposed...

Morning and Monday: critical periods for the onset of acute myocardial infarction. The GISSI 2 Study experience.

Abstract: The onset of acute myocardial infarction (AMI) is unevenly distributed over the 24 h and the week. While presence of a morning peak is generally agreed upon, contrasting results had been obtained regarding other periods of the day, probably due to differences of origin, size and composition of the populations. The 24 h and weekly distributions were studied within 6 h from the beginning of the symptoms in a population following a Latin life-style, who were enrolled in the GISSI 2 Study (n = 11472). Subgroups (smokers, the elderly (> 65 years), diabetics, hypertensives) were also considered. Six hour periods starting at midnight were tested for uniformity. Circadian non-uniformity was found. Events increased in the morning hours and reduced during the night regardless of the day of the week. The night and day difference was attenuated in smokers and diabetics. Non-uniformity of the events was also found among the days of the week. AMI significantly increased in non-smokers on Monday. We suggest that there is a night-day gradient (characterized by the short time interval between the two frequency extremes) in the time of onset of AMI. The different distribution in smokers stresses the possible unfavourable and masking effect of a heightened sympathetic tone during the day while the general protective role of the night hours is preserved. Moreover, the increased incidence of events on Monday may suggest the importance of the shift from a period of non-scheduled to scheduled activity.

Different patterns of light exposure in relation to melatonin and cortisol rhythms and sleep of night workers

Abstract: There is strong evidence to suggest that circadian psychophysiological adaptation processes are modified by light, depending on its intensity and timing. To characterize such modifications and determine whether they are associated with an alteration in the day/night pattern of melatonin excretion, measurements were obtained around the clock in 14 permanent night workers, each studied over a 48 hr period in the field. The light exposure behavior of these workers was studied with a newly developed light dosimetry by measuring light intensity at eye level. Physical activity was continuously registered and sleep indices were obtained by sleep logs and activity markings. Circadian rhythms of melatonin and cortisol were analysed from salivary samples collected for 24 hr at 2 hr intervals. The interindividual variation of melatonin acrophase determined by cosinor analysis was greater than 180 degrees (from around midnight to noon) and that of cortisol was about 135 degrees (from early morning to afternoon). Hormonal phase positions coincided significantly with light exposure: the more bright light pulses in the morning (maximum lux between 0600 and 0900), the less were the melatonin and cortisol acrophases shifted into the day. There was also a negative correlation between melatonin acrophase shift and duration of the overall light exposure above 1500 lux. Morning light maximum and sleep onset correlated highly significantly. Night workers were divided into those with less than ('non-shifters', n = 9) and more than 6 hr deviation from midnight ('shifters', n = 5) of the melatonin acrophase. The group comparison revealed a marked difference of the mean melatonin concentrations at night, and at 0700.(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of frequently rotating shiftwork on sleep and the family life of hospital nurses.

Abstract: The effects of three frequently rotating shifts in an irregular sequence on the daily activities of 239 Japanese female hospital nurses were studied by the time-budget method. The nurses recorded their daily activities for several consecutive days. The questionnaire was returned by 80·8% of the participants, and recordings of 1016 days were analysed. A two-way analysis of variance clarified that the shift combination influenced the daily activities. The most distinct result was that nurses spent significantly more time on free-time activities on the day when they worked the night shift followed by the evening shift than they did on the day when they worked any other shift combination. Nurses offset sleep deprivation either by sleeping during the day before and after working the night shift (82–100%) or by sleeping 2 to 4 h later in the morning after working the evening shift and on days off. There was a strong positive correlation between total sleep time (including day sleep) and the length of the interv...

Melatonin rhythms in Arctic urban residents

Abstract: Stokkan K-A, Reiter RJ. Melatonin rhythms in Arctic urban residents. J. Pineal Res. 1994: 16: 33–36. Abstract The 24-hr rhythm of salivary melatonin was measured in persons living in the city of Tromso (70°N) at the following times of the year: in January at a day length of 2 hr of twilight, in June under continuous sunshine, and in March and September at about 12 hr light and 12 hr darkness. The hormone patterns varied widely between individuals, but, in general, they were consistent within most individuals between the seasons. Highest peak values occurred in January when the mean level was also significantly higher than at any other time of year. The lowest mean levels occurred in June. Although individual rhythms were not always apparent, the mean patterns showed significantly elevated melatonin concentrations during the night at all seasons. The June melatonin peak was similar to that in March and September, but appeared to be phase-delayed with increased melatonin concentrations from midnight until 0900. It is assumed that the delayed melatonin peak in June may be associated with a tendency among people to shift their activity/rest rhythm and that the pineal sensitivity to light is reduced in the morning in summer.

Heart rate changes in chronic insomnia

Abstract: This study assessed physiological activity in patients with chronic insomnia before sleep, during sleep and in response to acute stress. Twenty-four subjects with chronic insomnia and 25 normal sleepers slept in the laboratory overnight and were given a stressful performance task in the morning. Heart rate was significantly higher in the insomniac group at night. The next morning, heart rate was not different at baseline, but was significantly higher during the performance task in the insomniac group. These results are discussed as supporting the notion that insomniacs have greater physiological responsivity to stress. Further research is needed to determine if altered physiological activity is a cause or consequence of insomnia.

Regional Rainfall Climatologies Derived from Special Sensor Microwave Imager (SSM/I) Data

Abstract: Climatologies of convective precipitation were derived from passive microwave observations from the Special Sensor Microwave Imager using a scattering-based algorithm of Adler et al. Data were aggregated over periods of 3-5 months using data from 4 to 5 years. Data were also stratified by satellite overpass times (primarily 06 00 and 18 00 local time). Four regions (Mexico, Amazonia, western Africa, and the western equatorial Pacific Ocean (TOGA COARE area) were chosen for their meteorological interest and relative paucity of conventional observations. The strong diurnal variation over Mexico and the southern United States was the most striking aspect of the climatologies. Pronounced morning maxima occured offshore, often in concativities in the coastline, the result of the increased convergence caused by the coastline shape. The major feature of the evening rain field was a linear-shaped maximum along the western slope of the Sierra Madre Occidental. Topography exerted a strong control on the rainfall in other areas, particularly near the Nicaragua/Honduras border and in Guatemala, where maxima in excess of 700 mm/month were located adjacent to local maxima in terrain. The correlation between the estimates and monthly gage data over the southern United States was low (0.45), due mainly to poor temporal sampling in any month and an inadequate sampling of the diurnal cycle. Over the Amazon Basin the differences in morning versus evening rainfall were complex, with an alternating series of morning/evening maxima aligned southwest to northeast from the Andes to the northeast Brazilian coast. A real extent of rainfall in Amazonia was slightly higher in the evening, but a maximum in morning precipitation was found on the Amazon River just east of Manaus. Precipitation over the water in the intertropical convergence zone (ITCZ) north of Brazil was more pronounced in the morning, and a pronounced land-/sea-breeze circulation was found along the northeast coast of Brazil. Inter-comparison of four years revealed 1992 to be the driest over Amazonia, with about a 23% decrease in mean rate compared to the 4-year mean estimated rain rate.

Morning increase in ambulatory ischemia in patients with stable coronary artery disease. Importance of physical activity and increased cardiac demand.

Abstract: BACKGROUND The morning increase in asymptomatic ambulatory ischemia may be due to heightened coronary tone, increased physical activity, or both. If ambulatory ischemia is primarily due to physical activity, then alterations in the schedule of physical activity should be reflected in a corresponding alteration in the occurrence of ischemia. This study was designed to examine the relation between activity patterns and the frequency of ambulatory ischemic episodes and the effect of nadolol on these relations. METHODS AND RESULTS A double-blind, randomized, placebo-controlled, crossover trial of nadolol versus placebo was performed in 20 patients with stable coronary artery disease. At the end of each 2-week treatment phase, patients were hospitalized for 48 hours. In the hospital, there was a regular activity day (awaken and assume normal activities at 8:00 AM) and a delayed activity day (awaken at 8:00 AM, arise at 10:00 AM, and begin normal activity at noon). Ambulatory ECG monitoring was performed throughout the hospitalization. On the regular activity day, there was a morning increase in heart rate and in the number of ischemic episodes during therapy with placebo that began at 8:00 AM. In contrast, on the delayed activity day, there was a 4-hour phase shift of the increases in heart rate and the increase in ischemic episodes (ie, at noon) corresponding to the onset of physical activities. Therapy with nadolol caused a 50% reduction in the total number of ischemic episodes (129 versus 65, placebo versus nadolol; P or = 5 beats per minute. Although nadolol caused a significant reduction in the total number of episodes preceded by a heart rate increase compared with placebo (99 versus 38 episodes, P CONCLUSIONS The morning increase in ambulatory ischemic episodes is due to physical activity patterns. The majority of ischemic episodes are preceded by a heart rate increase, and it is these episodes that are primarily responsible for the morning increase in ischemia. Therapy with nadolol caused a reduction in the total number of ischemic episodes solely by reducing those episodes preceded by a heart rate increase. In contrast, nadolol caused a significant increase in the number of ischemic episodes not associated with a heart rate increase, perhaps in part because it potentiated coronary vasoconstriction.

Cyclic changes in the concentrations of peripheral blood immune cells during the normal menstrual cycle.

Abstract: The optimal availability of immune cells in the peripheral blood streams of women may play a critical role in their response to disease and therapeutic interventions. This study was designed to examine concentrations of circulating white blood cells (WBC) including lymphocyte subsets, during the 24-hr daily and 28-day menstrual cycles. Venous blood (20 ml) from five healthy young women was obtained at 0, 6, 12, and 18 hr on the 6th and 22nd day of the normal menstrual cycle. Cortisol, progesterone (P4), estradiol (E2), total WBC, granulocyte, monocyte, and total lymphocyte levels were measured. Using fluorescent activated cell scanning, levels of T, B, Helper (H), Suppressor (S) and Natural Killer (NK) cells were also determined. Significant differences in the diurnal and Day 6 and 22 means were identified using analysis of variance and the Student's t test. Mean WBC counts differed significantly between individuals and ranged from 3.63 +/- 0.33 to 8.60 +/- 1.00 on Day 6 and 3.75 +/- 0.56 to 9.45 +/- 0.98 on Day 22 (P < 0.05). Fluctuations in the concentrations of peripheral blood immune cells followed a similar pattern for the time points selected. They were lowest in the morning at 6 hr and reached peak concentrations in the evening at 17 hr or at midnight at 24:00 hr. Total WBC and granulocyte levels were consistently highest in the evening at 18 hr while lymphocyte levels either peaked in the evening or at midnight. Between midnight and early morning, levels of WBC, lymphocytes, T, B, H, and S cells all decreased significantly (P < 0.01) and subsequently increased significantly, between 6 hr and noon or noon and 18 hr (P < 0.01). When compared every 12 hr, the levels of WBC, granulocytes, lymphocytes, T, B, H, and S cells showed a significant day time rise between 6 and 18 hr (P < 0.02). NK cells revealed no significant fluctuations for any of the diurnal time point comparisons examined in this study. The WBC means for all subjects on Day 6 was 6.15 +/- 1.96 and on Day 22 was 6.39 +/- 2.14, evidence that the total number of white blood cells was not significantly altered between the 2 days. However when comparing specific time points during the day for the follicular (Day 6) and luteal (Day 22) phases of the menstrual cycle, significant differences were found. Most striking were the monocyte patterns, which revealed a nadir at 12:00 noon on Day 6 and a peak at the same time on Day 22.(ABSTRACT TRUNCATED AT 400 WORDS)

Voiding Frequency, Volumes and Intervals in Healthy Schoolchildren

Abstract: To study the micturition pattern in healthy schoolchildren, 242 children aged 7–15, who all considered themselves healthy, completed a frequency/volume chart for 24 hours. Bed-wetting occurred in 21 (8.7%) and daytime incontinence in 19 (7.9%) children. Both symptoms occurred in four subjects, all girls. The incontinent children were excluded, leaving 206 subjects in the study. The healthy children voided 2–10 times a day, with 95% having a voiding frequency of 3–8. Twenty-three (11.2%) voided once during the night. All volume parameters varied greatly, both interindividually and intrain-dividually, independently of sex but weakly correlated to age and body parameters. The morning voiding was the largest, while the last before bedtime was the smallest. The interval between two voidings was longest in the morning decreasing towards the evening. The healthy child has a great ability to adapt the micturition pattern to social activities, which means — “to be the Boss of the Bladder”.

Effects of exercise intensity, duration, and time of day on fibrinolytic activity in physically active men

Abstract: The purposes of this investigation were to determine: 1) whether the fibrinolytic responses to acute, submaximal exercise were best related to intensity, duration, or total caloric expenditure; and 2) whether the time of day exercise is performed affects the fibrinolytic response. Twelve physically active men (mean age = 34.8 +/- 4.0 yr) performed four 30-min exercise sessions: 50% VO2max, a.m. and p.m., and 80% VO2max, a.m. and p.m. Blood samples were analyzed for tissue plasminogen activator (TPA) activity and plasminogen activator inhibitor-1 (PAI-1) activity. Data were analyzed using a three-way ANOVA with repeated measures. TPA activity: preexercise TPA did not differ among the four sessions. TPA increased with exercise in all sessions except the 50% a.m. session. Exercise at 80% increased TPA more than 50% (P < 0.001) and evening sessions increased TPA more than morning sessions (P < 0.05). PAI-1 activity: preexercise PAI-1 activity was higher during the morning than evening and significantly decreased with exercise in all sessions except the 50% p.m. session. It was concluded that changes in fibrinolytic activity appear to be influenced primarily by exercise intensity rather than duration or total caloric expenditure. Additionally, time of day of exercise performance significantly influenced fibrinolytic activity.

Circadian variation of haemodynamics in patients with essential hypertension: comparison between early morning and evening.

Abstract: ObjectiveAn increased incidence of cardiovascular accidents in the morning has been reported, but the reason why is not clear. We measured 24-h haemodynamics and focused on its change in the morning.DesignTo study the circadian variation of haemodynamics, we recorded 24-h direct blood pressure and e

Morning reduction of cerebral vasomotor reactivity.

Abstract: We measured cerebral vasomotor reactivity during normoventilation, hyperventilation (hypocapnia), and breathing of 6% CO2 (hypercapnia) in 20 normal subjects during the hours of 6 to 8 AM, 1 to 3 PM, and 7 to 9 PM. Cerebral vasomotor reactivity was calculated, using transcranial Doppler, as percent change in the mean blood flow velocity of the middle cerebral artery per mm Hg change in end-tidal CO2 during hypocapnia and hypercapnia. Vasomotor reactivity during hypercapnia was lower in the morning (1.72 +/- 0.66 %/mm Hg) than in the afternoon (2.34 +/- 0.74 %/mm Hg, p < 0.01) and evening (2.31 +/- 0.56 %/mm Hg, p < 0.001). Vasomotor reactivity during hypocapnia did not vary significantly during the three periods (2.34 +/- 0.59 %/mm Hg in the morning, 2.43 +/- 0.51 %/mm Hg in the afternoon, and 2.26 +/- 0.52 %/mm Hg in the evening). This reduced morning response to hypercapnia suggests diminished vasodilator reserve during this period, and may be related to the increased stroke risk during the morning hours.

Morning versus evening administration of nifedipine gastrointestinal therapeutic system in the management of essential hypertension.

Abstract: The nifedipine gastrointestinal therapeutic system (GITS) is a recently developed controlled-release formulation for once-a-day dosing. We evaluated the influence of morning versus evening administration of the drug in a randomized double-blind cross-over study including 15 essential hypertensives. Five patients had to be excluded from blood pressure analysis because of noncompliance (three cases) or intolerable side effects (two cases). To assess the exact duration of the antihypertensive efficacy noninvasive automatic ambulatory blood pressure monitoring was performed. After a placebo period patients were given 30 mg nifedipine GITS either at 1000 or 2200 hours. Twenty-four-hours systolic and diastolic blood pressure profiles documented a sustained antihypertensive effect of both nifedipine regimens throughout the whole period without affecting the circadian rhythm. Statistical analysis revealed no significant difference between morning and evening administration. Two patients stopped their medication because of intolerable side effects (fatigue and muscle cramps, respectively). Two more cases suffered from mild reversible headache which provoked no discontinuation of the drug. In conclusion our results document a sustained antihypertensive efficacy of 30 mg nifedipine GITS in patients with moderate essential hypertension. Time of administration has no impact on day- and nighttime blood pressure control.

Diurnal urinary corticoid excretion in the human and gorilla.

Abstract: Urinary corticoids were measured in humans (n = 9) in frequently collected urine samples taken during a 48 hr period, and in captive western lowland gorillas (n = 5) and free-ranging mountain gorillas (n = 3) from samples taken from 0700 to 1800 hr. In each study, the highest concentrations occurred in the morning hours, then declined gradually, reaching the lowest levels in the afternoon to evening. These data show that a similar diurnal pattern of corticoid excretion does occur in these species. We suggest that if single-sample urine collection for determination of hyperadrenal activity is to be used, urine is best collected during hours of low corticoid excretion. © 1994 Wiley-Liss, Inc.

Timing for administration of an antihypertensive drug in the treatment of essential hypertension.

Abstract: To find the best timing for administration of long-acting antihypertensive drugs, we gave nitrendipine, a calcium antagonist of the dihydropyridine group, once a day to six hospitalized and drug-free patients with essential hypertension, changing the time of administration and studying the effects on the circadian rhythm of blood pressure. After control values of 24-hour blood pressure variations were taken with patients on placebo, a 10-mg tablet of nitrendipine was given for 3 days on three occasions--at 6 AM on awakening, at 8:30 AM after breakfast, and at 6 PM after supper; 24-hour blood pressure values for each period were recorded on the third day. The 24-hour blood pressure values during the control period showed a biphasic circadian rhythm, with higher values during wakefulness and lower values during sleep. The control period was also characterized by a rapid rise in blood pressure on awakening, the so-called morning surge of blood pressure, and a gradual decline during sleep at night. Although the morning surge was not completely suppressed by nitrendipine given after breakfast, it was diminished by the drug given on awakening or after supper; the latter brought a deeper decline in blood pressure during sleep compared with other times. The average of 24-hour blood pressure values obtained by nitrendipine given on awakening was the lowest among the three occasions. Thus, administration of long-acting calcium antagonists with a rapid onset of action on awakening in the early morning seems to be a more rational and beneficial alternative than the conventional administration after breakfast.(ABSTRACT TRUNCATED AT 250 WORDS)

The Dübendorf Study: a population-based investigation on normal values of blood pressure self-measurement.

Abstract: There is evidence that self-measurement of BP increases precision, reproducibility and prognostic value of BP measurement. However, generally accepted normal values for BP values obtained by self-measurement are still missing. The present study was undertaken to investigate differences between office and self-measured blood pressure; 503 randomly selected inhabitants (265 men and 238 women, age 20-90 years, mean age 46.5 +/- 12.9 years) of the small town of Dubendorf in Switzerland were studied. The subjects were not preselected according their BP levels, only patients taking antihypertensive drugs were excluded. Self-measurement was performed at home by the subjects during 14 days in the morning between 6 and 8 am and in the evening between 6 and 8 pm (mean of 26.7 measurements). Office BP was taken before and after the two week period. Mean office BP (130.0 +/- 16.5/82.1 +/- 11.1 mmHg) was significantly (P < 0.01) higher than mean self-measured BP (123.1 +/- 14.6/77.6 +/- 10.7 mmHg). There was no significant difference between first and second office BP measurement. Morning self-measured BP was lower than evening pressure (delta 4.0/1.4 mmHg, both P < 0.01) and the mean was taken for comparison with office BP.(ABSTRACT TRUNCATED AT 250 WORDS)

Nasal congestion during the menstrual cycle.

Abstract: Oestrogens have been considered to cause nasal congestion during the menstrual cycle and during pregnancy. The aim of the present study was to evaluate the degree of nasal congestion during the menstrual cycle in healthy women. Nasal peak expiratory flow (nPEF) was measured and subjective nasal stuffiness was scored morning and evening by 27 women for 3 months and by 14 women for 6 months. During the menstrual days, when the serum oestrogen level is lowest, the morning nPEFs were significantly lower compared with the rest of the cycle (P = 0.0012). The difference was most pronounced for the second day of the cycle (P = 0.00034). The correlation between nPEFs and the subjective scores was high (R = 0.98), while the coefficient of variation within the series of three nPEF recordings was low (6.4%). It is concluded that the nasal obstruction experienced during menstruation cannot be explained by increased serum levels of oestrogen.