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At least 19 recordsLinked to original sources
PubMed1978

Seasonal variation in admissions of psychiatric patients and its relation to seasonal variation in their births.

Inpatient admissions to all psychiatric hospital beds in England and Wales in 1970-73 were studied by month of admission for eight diagnostic groups. The admission rates for schizophrenia showed a pronounced seasonal variation, with a maximum in summer. The seasonal pattern for schizophrenia was very similar to the one shown for mania, although somewhat less marked. The admission rates for neurosis and for the large group of 'all other non-psychotic mental illness' showed little evidence of seasonal variation as there was could largely be explained by social factors. In schizophrenic and manic patients, the pattern of seasonal admissions (peak months July and August) is similar to the pattern reported for their births (peak months February and March). This is consistent with the hypothesis of an abnormal seasonal pattern of parental conception as the cause of the abnormal birth pattern.

Bipolar Disorder↗
PubMed1979

[Seasonal variations of a forest soil microflora (author's transl)].

Variations between seasonal samplings of a forest soil were studied during a one year cycle. The total number of microorganisms was maximal in march, while qualitative variations of the bacterial and fungal flora were unimportant. Electron microscope studies showed physiological differences and enabled to evaluate the seasonal variations of the type of associations of soil microbes.

Bacteria↗
PubMed1975

Seasonal variations in the composition of urine in relation to calcium stone-formation.

1. A retrospective cross-sectional study was carried out on data derived from single 24 h urine collections from 246 male idiopathic calcium stone-formers. 2. The daily urine volume and pH and the exretions of calcium, oxalate, phosphate, creatinine and magnesium were related to the time of year when the urine was collected, and the saturation of urine with calcium oxalate and octocalcium phosphate calculated for each month. 3. There were significant seasonal variations in the urinary excretion of calcium and oxalate, each showing a maximum during the summer months and a minimum in the winter. There was no significant seasonal variation in urinary pH, volume, creatinine, phosphate or magnesium. 4. There was a significant increase in the saturation of urine with calcium oxalate and a trend towards higher saturation levels of octo-calcium phosphate in the summer. These changes were dependent only on the seasonal variation in urinary calcium and oxalate and not on urine volume. 5. A retrospective study of the seasonal incidence of stone episodes among these 246 stone-formers showed that the rate of stone passage per month was 50% higher in the summer than in the winter. There was no significant seasonal variation in the incidence of stones removed surgically.

Calcium↗
PubMed1977

Seasonal variations in urinary excretion of calcium and oxalate in normal subjects in patients with idiopathic hyperclaciuria.

A longitudinal 9-year retrospective study of 24-hour urinary calcium values has been made in a metabolic stone clinic amongst patients with idiopathic hypercalciuria. No seasonal variations could be observed in contrast ot a previous study from Leeds, A prospective longitudinal study was made of 24-hour urinary calcium values in a small group of normal subjects. No seasonal variation could be ovserved. In the prospective study no seasonal variations in urinary oxalate could be observed. In a 2-year longitudinal study of stone patients with idiopathic hypercalciuria, urinary oxalate was found to be higher in the summer than in the winter. This was attributed to the combination of a higher intake of oxalate-rich foods in the summer, and the low calcium diet with which they were treated.

Calcium↗
PubMedDate not supplied

Effects of seasonal variations, acute hypothermia and physostigmine on cardiac acetylcholine, tissue glycogen and blood sugar concentrations in frogs.

The effects of seasonal variations and the effects of acute hypothermia (8.0 degrees) and/or physostigmine (PHY) in different seasons have been studied on the tissue glycogen, cardiac acetylcholine (ACh) and blood sugar contents in frogs. Seasonal variations had no significant effect on cardiac cholinergic activity. However, cardiac ACh concentration was significantly reduced by hypothermia in all seasons. The extents of increase in cardiac ACh in PHY pretreated hypothermic frogs indicate that hypothermia depresses cardiac cholinergic acitity much more in summers than in rainy and winter seasons. The tissue glycogen contents and blood sugar concentrations were significantly lower in winter season than those in summer and rainy seasons. Hypothermia produced marked tissue glycogenolysis and hyperglycaemia during summer and rainy seasons and not during winters. In general PHY had no effect on tissue glycogen contents in any season, but it produced hyperglycaemia during rainy and winter seasons. PHY pretreatment increased cardiac, hepatic and muscle glycogen contents and produced hyperglycaemia in hypothermic winter frogs, and it increased ventricular and muscle glycogen contents during summer and hepatic glycogen during rainy seasons, there being no significant effects on blood sugar.

Acetylcholine↗
PubMed1979

Seasonal variations in the occurrence of urinary tract infections among children in an urban area in Finland.

The seasonal variations in the incidence of urinary tract infections (UTI) were studied in a series of 992 verified episodes of UTI treated between 1965 and 1974. The incidence was highest during November and lowest during the summer months. Summer episodes, moreover, tended to be the most severe. Seasonal variations were less marked among girls, than amond boys, except in the group of teenage girls in which peak incidences occurred in March and in September. Among the boys, a single peak incidence was recorded in July. The results of the analysis of weather type performed in this study showed that unseasonable types of weather, that is, cold and dry weather in autumn, warm and rainy weather in winter, and warm and dry weather in spring, were accompanied by a clear increase in the monthly number of episodes of UTIs. The difference in the monthly frequency of UTIs between the most and the least favourable types of weather was about two-fold.

Adolescent↗
PubMedDate not supplied

[Seasonal variations of cellular composition of human semen (author's transl)].

Sperm samples taken fortnightly from 14 young europeans over a period of 8 months show evidence of a seasonal variation in the concentration of spermatozoa and in the frequency of abnormal sperm (teratospermy). Both factors are highest in winter and lowest in springtime. A study of 3,000 spermograms established during consultations for sterility over the last 2 years did not clearly reveal the same trends, however, a statistical analysis of the results leads to the conclusion that several hundred examinations per month would be needed to show a significant seasonal variation in such a heterogeneous sample.

Adolescent↗
PubMed1979

[Seasonal variation of menarche and month of birth (author's transl)].

Seasonal variations in the occurrence of menarche in 1226 Japanese girls are not uniform, when they were divided into two groups by their season of births. Summer trough (May-July) was inapparent in girls born in summer (May-October), and winter trough (February-March) was less deep in girls born in winter (November-April). No differences were found in fall trough (September-November) between both groups. Girls born in summer (or winter) seem to be resistant to some summer (or winter) factors, which inhibit the occurence of menarche.

Adolescent↗
PubMedDate not supplied

[Seasonal variations in epinephrine (E) and norepinephrine (NE) levels determined in organs of eel (author's transl)].

E and NE concentrations were measured by using a spectrofluorimetric method in various organs of eels, for a one year period. NE was found at higher levels than E in the whole brain, the heart, and the spleen. Maximal E levels occurred in kidney. Moreover (E + NE) sum is 40 to 190% higher than during spring and summer when compared to autumn and winter levels. According to the fact that seasonal variations of catecholamines were not found in the eel plasma, these results suggest that the observed seasonal variations can be related to fluctuation in CA amounts localized in synaptic structures.

Animals↗
PubMed2026

Seasonal variation in the office and ambulatory blood pressure control in patients treated with two dual antihypertensive therapies.

We investigated seasonal variation in the office and ambulatory blood pressure control in hypertensive patients treated with two single-pill dual-combination antihypertensive therapies. The study participants (n&#x2009;=&#x2009;560) were hypertensive patients enrolled in a 24-week therapeutic study. Antihypertensive treatment was initiated with amlodipine/benazepril 5/10&#x2009;mg/day or benazepril/hydrochlorothiazide 10/12.5&#x2009;mg/day, with the possible up-titration to 10/20&#x2009;mg/day or 20/25&#x2009;mg/day during follow-up, respectively. Office blood pressure was measured at each clinic visit, and ambulatory blood pressure monitoring was performed at baseline and 24-week follow-up. At 24 weeks of follow-up, in patients who continued antihypertensive treatment (n&#x2009;=&#x2009;511), the proportion of up-titration to higher dosages was significantly different across seasons of treatment commencement in the benazepril/hydrochlorothiazide group (P&#x2009;=&#x2009;0.002), but not in the amlodipine/benazepril group (P&#x2009;=&#x2009;0.84). The between-group difference was significantly different in 134 patients who commenced treatment in winter (18.9% vs. 5.0%, P&#x2009;=&#x2009;0.02), but not in 377 patients who commenced treatment in the other seasons (P&#x2009;&#x2265;&#x2009;0.33). The control rate of office blood pressure (<140/90&#x2009;mmHg) was significantly different across seasons of treatment commencement in the amlodipine/benazepril group (P&#x2009;=&#x2009;0.01), but not in the benazepril/hydrochlorothiazide group (P&#x2009;=&#x2009;0.16). The mean changes from baseline to 24-week follow-up tended to be smaller in the benazepril/hydrochlorothiazide than amlodipine/benazepril group in 24-h (mean between-group difference, -2.8&#x2009;mmHg) and daytime diastolic blood pressure (mean between-group difference, -3.2&#x2009;mmHg) in patients who commenced treatment in winter, though statistical significance was not achieved (P&#x2009;&#x2265;&#x2009;0.07). In conclusion, there was seasonality in the clinic and ambulatory blood pressure-lowering effect of antihypertensive drug combinations, with a marginally significant difference in treatment intensity and blood pressure control between treatment with amlodipine or hydrochlorothiazide in combination with benazepril.

Ambulatory blood pressure↗
PubMedDate not supplied

[Age-related and seasonal variations in the ATPase system of mitochondria of skeletal muscles in rabbit].

Seasoned variations in the activity of Mg++-ATPase and Mg++-DNP-ATPase have been revealed in studies on ATPase system of mitochondria of skeletal muscles of newborn, 7-, 10-day and adult rabbits. The degree of activation of ATPase by 2-4-DNP did not depend on the age of animals and the season of year. Absolute values for DHPATPhase were lower in young animals in spring. The activity of Mg++- and Mg++-DNP-ATPases and the extent of activation of the enzymes by Mg++ increased with the increase in the age of animals.

Adaptation, Physiological↗
PubMed1979

The use of a Kolmogorov--Smirnov type statistic in testing hypotheses about seasonal variation.

This paper presents a non-parametric method for testing departures from a uniform seasonal variation in incidence of disease. The method may be used either with exact dates of incidence when they are available or with monthly totals. It is equally valid for sinusoidal and non-sinusoidal departures from uniformity. A simulation study shows it to be much more powerful than other non-parametric alternatives and nearly as powerful as Edwards's test in detecting sinusoidal departures.

Epidemiologic Methods↗
PubMed1978

[Seasonal variations in the incidence of the conception of multiple pregnancies in two centuries (author's transl)].

Seasonal variations in the incidence of the conception of multiple pregnancies are compared in the same population area in two centuries. 12,617 singleton and 101 twin pregnancies from 1803 to 1852 are compared to 63,967 singleton, 473 twin and 5 triplet pregnancies from 1965 to 1970. In both groups the percentage decrease of multiple conceptions during the first three months of the year was higher than the percentage decrease of singleton conceptions. In both groups the percentage increase of multiple conceptions during the summer months was higher than the percentage increase of singleton conceptions. The question of the influence of light on the hypothalamic-pituitary centres as a cause of the variations in multiple conceptions is discussed. The incidence of multiple conceptions has decreased since the beginning of the 19th century independant of the progress in obstetrics and perinatology. The decreased rate of multiparas and especially older multiparas is suggested as the likely cause for this decrease.

Female↗
PubMed1977

[Seasonal variations in frog liver glycogen metabolism (author's transl)].

Glycogen metabolism in frog (Rana ridibunda) liver is subject to seasonal variations. Hepatic glycogen and glycogen synthase levels are highest in the fall and winter months and lowest in the summer months, whereas glycogen phosphorylase activity is highest in spring and summer and lowest in fall and winter months. Blood glucose levels show a clear increase during the months of March, June-July and November over the mean level for the rest of year (19.0 +/- 5.5 mg glucose/100 ml serum). Results indicate that the animal accumulated glycogen in the fall to be consumed during the winter. Glycogen levels are in direct proportion to glycogen synthase activity levels (I-form and total activity) and in inverse proportion to glycogen phosphorylase (phosphorylated form) activity levels, which would suggest that these enzymes exercise a direct control over glycogen levels.

Animals↗
PubMed1979

Seasonal variation and the influence of body temperature on plasma concentrations and binding of thyroxine and triiodothyronine in the woodchuck.

Woodchuck plasma was collected during four seasons of the year and assayed for total and dialyzable (free) T4 and T3 and for rT3. Plasma concentrations of total and free T4 and T3 were higher in the spring (T4, 5.4 +/- 0.6 microgram/dl; free T4, 3.0 +/- 0.4 ng/dl; T3, 202 +/- 22 ng/dl; free T3, 0.51 +/- 0.04 ng/dl) and lower in the prehibernatory fattening period in summer (T4, 2.3 +/- 1.0 microgram/dl; free T4, 1.2 +/- 0.5 ng/dl; T3, 45 +/- 27 ng/dl; free T3, 0.16 +/- 0.10 ng/dl) and fall (T4, 3.2 +/- 1.0 microgram/dl; free T4, 1.3 +/- 0.2 ng/dl; T3, 130 +/- 12 ng/dl; free T3, 0.25 +/- 0.02 ng/dl). In spite of the extremely high concentrations of T3 in the winter (437 +/- 32 ng/dl), free T3 concentrations (0.034 +/- 0.003 ng/dl), when measured at the appropriate temperature for hibernation, were significantly lower than those found at other seasons of the year. Plasma binding of T3 was lower during the summer and increased again to approximately double the spring value during the winter. rT3 was at or below the sensitivity of the method (6 ng/dl) at all seasons. It is suggested that the wide seasonal variations in thyroid hormone concentrations and altered plasma protein binding may represent important adaptations influencing the metabolic rate and the process of hibernation in the woodchuck.

Animals↗
PubMed1978

Seasonal variations in weight of children attending an under-fives clinic in Lesotho.

The incidence of weight loss between successive visits, prevalence of under centile 3 weight-for-age and over centile 97, showed a marked bimodal annual variation for 1243 children attending an under-fives clinic. 9949 weighings on 661 boys and 682 girls over a five year period, contributed to the database. Season of birth also significantly influenced the centile distributions of weight-attained-for-age. Children over 1 1/2 years old showed considerably higher rates of weight loss (about 1 in 5 children attending in their fifth year of life), than children younger than the mean age of weaning. The rates of weight loss, together with seasonal variation, was considerably higher for a group of 'Regular Attenders' to the clinic, than for a group of 'Low Attenders'. Seasonal influences on growth need to be taken into accounts in evaluating the quality of care and outcome produced by under-fives clinics.

Body Weight↗