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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↗

PubMed1975

Seasonal patterns of sleep stages and secretion of cortisol and growth hormone during 24 hour periods in northern Norway.

A group of 7 healthy male subjects was studied in regard to sleep stages and 24 h plasma cortisol and growth hormone patterns during the 4 seasons of the year in an Arctic environment (Tromsø, Norway). No difference in total sleep or sleep stage per cents was found for any of the yearly seasons. A small but statistical significant increase in mean plasma cortisol concentration and amount secreted for 24 h was found for the autumn-winter seasons, as compared with the spring and summer. However, no difference in the circadian curve of cortisol hormonal pattern was found. All subjects secreted growth hormone shortly after sleep onset at night and no difference was found as a function of season of the year.

Adult↗

PubMed1975

Changes in social organization during the breeding season of wild talapoin monkeys.

Two adjacent troops of talapoin monkeys were studied near Mbalmayo, Cameroon, during a predicted 3-month breeding season. Mating continued for just over 2 months. One troop began to mate at least 2 weeks before the other, suggesting that, though climatic changes were probably important, precise timing was mediated through some intra-troop social facilitation effect. Before the breeding season, adult males and females lived in separate sub-groups. Males began to move into female sub-groups before there was any sign of the perineal swellings characteristic of receptive talapoin females. Copulation occurred only with females with medium or large swellings, except towards the end of the season. It is probable that the majority of females were monoestrous. At the height of the mating period, females joined mainly male sub-groups, leaving their infants with the mainly female groups which also included a few males. Copulations were observed in both these types of sub-groups. Consort behaviour was not observed, males frequently returning to all-male sub-groups immediately after ejaculation. Intersexual grooming was not characteristic of sexual interactions. At the end of the season, adults were seen more frequently in groups of their own sex or with juveniles only, and there was some indication that increased aggressiveness by newly pregnant females might be partly responsible for this separation.

Age Factors↗

PubMed1979

Seasonal variation of plasma glucagon concentrations in men.

In an attempt to understand a role of glucagon in seasonal acclimatization in men, measurements of plasma glucagon, blood free fatty acids (FFA), blood glucose, blood ketone body (beta-hydroxybutyrate) and hematocrit were made in 13 male and 8 female college staff members, aged 20 to 42, once a month for one year. Blood samples were obtained at 4:00 to 5:00 p.m, between meals. Average monthly temperatures during the study were as follows; Jan. -7.8, Feb. -5.6, March -3.7, Apr. 4.6, May 11.4, June 18.3, July 23.9, Aug. 22.0, Sept. 14.7, Oct. 7.5, Nov. 1.4, Dec. -4.2 (degrees C). Plasma glucagon, blood FFA and blood ketone body exhibited significant monthly variation in both sexes. Plasma glucagon as well as blood FFA level was significantly higher in winter (Dec., Jan., Feb.) than in summer (June, July, Aug), whereas blood ketone body level was lower in winter than in summer. Plasma glucagon level was significantly lower in female than in male subjects. A significant positive correlation was observed between plasma glucagon and blood FFA levels throughout the year. Seasonal variations of blood glucose and hematocrit were not observed. These results suggest that seasonal variation in glucagon secretion is associated with seasonal changes in ambient temperatures as one of the strategies for climatic acclimatization through regulation of lipid metabolism.

Acclimatization↗

PubMed1978

Seasonal birth pattern in Sweden in relation to birth order and maternal age.

The influence of both maternal age and parity on seasonal birth patterns in Sweden was studied, using the Swedish Medical Birth Register for 1973. The register contained reports of 109 342 pregnancies. A test for seasonality, using a squared sinus function and an analysis of variance, was performed for each age and parity group. Significant differences were shown for parity irrespective of age and age groups within parity groups. There was one exception: no influence of parity could be demonstrated in women more than 35 years of age. For the lowest and the highest age groups (all parities), there was no significant seasonality in birth rate tested by the squared sinus method. This was also true for parity 3 (age group 20--24) and parity 1 (age group 30--34). The other age groups and parity classes show a significant seasonality with a maximum of births in April and May.

Adult↗

PubMed1975

Effect of season on some characteristics of stallion semen.

Season had a pronounced effect upon seminal pH and refractometer 'protein', total carbohydrate, dry weight, total N2 and lactic acid in seminal plasma of first and second ejaculates. In addition, total seminal volume, spermatozoa per ml and per ejaculate, non-protein sulphhydryl and glycerylphosphorylcholine of second ejaculates were also influenced. There was a season difference in the concentrations of lactic acid in spermatozoa from first and in total N2 from spermatozoa in second ejaculates. The effects of season on seminal plasma were greater than those on spermatozoa. Spermatozoa in first ejaculates were less affected by season than those in secons ejaculates. This differential effect on first and second ejaculates was generally true of all seminal characteristics.

Animals↗

PubMedDate not supplied

[Seasonal changes in the reaction of the hypophyseal-adrenal system to adrenomimetics in the suslik Citellus erythrogenys].

Studies have been made on the reaction of the hypophysial-adrenal system to the injection of adrenalin and novodrin to the ground squirrel C. erythrogenys at various seasons of year and at different functional conditions of the animals. Together with seasonal variations in the basal level of corticosteroids in the peripheral blood, seasonal changes in the reaction of non-hibernating animals to adrenomimetics were found. Stimulating effect of the adrenomimetics was higher at spring, immediately after awakening, being significantly lower in summer and being absent before the onset of hibernation. At the same time, the sensivity of the adrenal cortex to ACTH was relatively high. Presumably, seasonal changes in the reaction of the hypophysial-adrenal system in the ground squirrels to adrenomimetics are associated either with changes in the sensitivity of the adrenoreceptors, or with changes in the reactivity of the central part of the hypothalamo-hypophysial-adrenal system.

11-Hydroxycorticosteroids↗

PubMedDate not supplied

[Seasonal fluctuations in the kallikrein-kinin system indices].

State of kallikrein-kinine system was studied in 100 persons of young and mature age during various seasons of year. Season variations in content of kininogen, kallikreinogen as well as in BAEE-esterase activity of blood serum were observed in young persons. In mature persons the season variations of antitryptic and kininase activities were also observed in blood serum. The kinine system of young persons was apparently less subjected to season variations as compared with the persons of mature age.

Adolescent↗

PubMed1979

The effect of seasonal changes and socio-economic status on urinary pH and specific gravity.

Specific gravity and pH of urine in the dry and the wet season in three socio-economic Nigerian groups have been studied. Samples were collected at 7 a.m., 11 a.m. and 3 p.m. High-income subjects had a significantly lower urinary pH than low-income. During the wet season pH values were lower than in the dry, but not significantly so. During the day S.G. values did not differ, neither did they in different seasons. But there were significant differences between high and low income groups. S.G. and pH samples of high and low income groups were similar in children and in their parents. In medical students S.G. and pH in 24-hour urines were similar to the morning value of high and middle income groups and were not affected by season, but the volume was. The relevance of these findings is discussed relative to the rarity of urinary calculi in Nigerians.

Adult↗

PubMed1979

Seasonal dimensions to rural porverty: analysis and practical implications.

This paper reports on a conference on seasonal dimensions to rural poverty. Presentations included specialised papers on climate, energy balance, vital events, individual tropical diseases, nutrition, rural economy, and women, and also multi-disciplinary case studies of tropical rural areas from the Gambia, Nigeria, Mali, Kenya, Tanzania, India and Bangladesh. While care is needed in generalising, the evidence suggested that for agriculturalists in the tropics, the worst times of year are the wet seasons, typically marked by a concurrence of food shortages, high demands for agricultural work, high exposure to infection especially diarrhoeas, malaria, and skin diseases, loss of body weight, low birth weights, high neonatal mortality, poor child care, malnutrition, sickness and indebtedness. In this season, poor and weak people, especially women, are vulnerable to deprivation and to becoming poorer and weaker. Seasonal analysis is easily left out in rural planning. When applied, it suggests priorities in research, and indicates practical policy measures for health, for the family, for agriculture, and for government planning and administration.

Agriculture↗

PubMed1977

Experimental and epidemiological estimation of seasonal and climato-geographical features of non-specific resistance of the organism to influenza.

One and the same series of live influenza vaccine from the strains B/Dushanbe/66 and B/Leningrad/67 or A2/Moscow/21/65 administered intranasally to non-immune persons in Leningrad and 'krasnodar in winter caused an increase in body temperature in 6.7-8% of vaccinated subjects, but in summer in 0.8%. In the transitional seasons of the year (in May and in October), 6.3-16.8% of reactions were observed in Murmansk and 0.1% in Krasnodar. An increase in antibodies in the vaccinated in Leningrad and Arkhangelsk in winter was observed 1.5 times more frequently than in summer. In Krasnodar, seroconversion occurred in only 5.7% in May and october, but in 31.3% in January; in Murmansk in 41.2-48% in May and in 75.6-78.8% in October. The seasonal as well as latitudinal and climatic differences in reactogenicity and antigenic activity of the vaccine can be explained by seasonal oscillations in non-specific resistance of people of influenza viruses. The importance of this factor in the mechanism of seasonal occurrence of influenza is discussed.

Adolescent↗

PubMed1977

The analysis of essential oils and extracts (oleoresins) from seasonings--a critical review.

A critical review of the analytical methods employed for the determination of the relevant components of seasonings is presented. Where the available methods were inadequate, new ones have been devised. Particular emphasis has been placed on those methods of analysis that provide a rapid and sufficiently accurate appraisal of seasoning extracts and essential oils from seasonings under routine control laboratory conditions. At the same time, the margin of error of these methods has been determined. The individual seasoning extracts were assessed according to the following criteria: (1) essential oil--cardamom, laurel leaves, cloves, origanum (marjoram), sage, and thyme; (2) essential oil and nonvolatile lipids--dillseed, coriander, caraway, mace, nutmeg, pimento (allspice), and celery seed; (3) essential oil and/or pungent ingredients--capsicum, ginger, and pepper; (4) essential oil and/or coloring matter--turmeric (curcuma) and paprika; (5) essential oil and other components--garlic, onion, and cinnamon.

Capsicum↗

PubMed1977

[Pre-seasonal treatment of hayfever with a pollen depot extract (author's transl)].

90 patients with "hayfever" - that means pollenallergic diseases of the respiration tract and the eyes - were treated in spring 1974 and 1975 with a tyrosinabsorbed grass and rye depot extract with three injections before the pollen-season. Only 16 patients had an isolated grass-rye-pollen-allergy in skin test, all the other patients had additional extrinsic allergies. These results were proved by RAST. One third of the patients had bad side-effects (27 out of 90) during the treatment. 17 patients showed general reactions and ten patients very strong local reactions. We think that these side-effects were caused by contact with antigens (hairs of animals, foods, flowers of trees) during therapy and acute or chronic infections. The results of therapy were asked by a questionnaire one year after the series of injections, there were 37 improved, 32 unchanged and/or worsened in pollen-season after treatment. Nevertheless the results encouraged to continue this treatment with the grass-rye-pollen-extract. It could be used as an "initial treatment" in pollinosis patients with a wide spread allergy just before the beginning of the pollen-season. It is necessary to fullfill all procedures of precaution which are in use in hyposensitizationtherapy to prevent stronger side-effects.

Adult↗

PubMed1979

Seasonal variation in the birth of left-handed schoolgirls.

The birth of left-handed girls in a school population displayed a seasonal trend, with a peak in November. No seasonal trend was seen in the birth of left-handed boys. The seasonal pattern of birth of left-handed girls is compatible with the hypothesis that nongenetic factors contribute to the occurrence of left-handedness.

Child↗

PubMed1978

Seasonal pattern in the rate of growth in height of children living in Guatemala.

Monthly increments of height for a sample of 164 Guatemala City school children are analyzed for the presence of a seasonal pattern in rates of growth. It is found that pre and post adolescent children follow a seasonal pattern of growth but adolescent children do not. It is suggested that the results are due to an effect of seasonal changes in ultraviolet light availability and the synthesis of vitamin D3 as mediated by the level of maturation of each child.

Adolescent↗

PubMed1979

Seasonal changes in the reproductive system of the female white-crowned sparrow, Zonotrichia leucophrys gambelii, in captivity and in the field. 2. The incubation patch.

The ventral apterium of free-living female White-crowned Sparrows (Zonotrichia leucophrys gambelii) becomes an incubation patch during the breeding season. At this time, it loses its feathers, increases in wet and defatted dry weight, and undergoes marked histological alterations. At times of year other than the breeding season, the apterium consists of a low squamous epidermis and a thin, poorly vascularized dermis of dense connective tissue. The dermis is separated from subcutaneous tissue by an internal elastic lamina. During the breeding season, the epidermis is a proliferative, stratified squamous epithelium with well-defined basal, intermediate, transitional, and cornified layers; and the dermis consists of a superficial layer of collagen and a deep layer of highly vascular areolar connective tissue, noticeably edematous and mildly inflamed. Blood vessels are frequently in large groups in the center of the dermis. Edema and hypervascularity are most pronounced during incubation, but the epidermis is best developed during egg-laying. The apterium reverts to its basal state after the incubation period. Captive females, which do not breed, do not develop incubation patches. Estrogen is apparently responsible for feather loss and collagen synthesis. It and other unidentified hormones (probably prolactin and/or androgens produce the hypervascularity, edema, and epidermal growth.

Animals↗

PubMed1977

Cromolyn sodium nasal solution in the prophylactic treatment of pollen-induced seasonal allergic rhinitis.

A large-scale multicenter investigation was undertaken in 3 cities with comparable pollen seasons and atmospheric pollen concentrations in order to obtain more definite information about the safety and efficacy of cromolyn sodium in the treatment of pollen-induced seasonal rhinitis. The 9-wk double-blind study was conducted in 104 patiets in Pittsburgh, Pa., Cleveland, Ohio, and Louisville, Ky., during the 1975 ragweed season. It indicated that a nebulized 4% aqueous solution of cromolyn sodium is effective in reducing sneezing, rhinorrhea, nasal congestion, and ocular irritation in ragweed hay fever patients. The efficacy of the drug was notable despite the fact that patients used an average of 52 mg instead of the recommended 62.4 mg daily. Cromolyn sodium did not appear to have a significant effect on transseasonal antiragweed IgE (IgEAR) levels. Patients acceptance of the cromolyn nasal solution was good, and there were no significant adverse reactions. The side effects, which were distributed equally between the drug and placebo groups, were mild and of limited duration.

Administration, Intranasal↗

PubMed1978

Studies of the androgen binding protein in the rete testis fluid of the ram and its relation to sexual season.

An androgen binding protein (ABP) with an electrophoretic mobility (Rf) of 0.56 is present in the rete testis fluid of adult rams. Its steroid specificity was found to be in the following order: 5alpha-DHT, testosterone, oestradiol-17 beta, dehydroepiandrosterone 5beta-DHT, androstenedione, cyproterone, cyproterone acetate, cortisol and progesterone. The characteristics of the ABP are similar to those found for the ABP of the testis and the epididymis of the rat and the rabbit. The concentration of ABP, determined by the dextran-coated charcoal method and sometimes confirmed by the steady-state polyacrylamide gel electrophoresis method, was significantly higher in the breeding season than in the non-breeding season (4.40 +/- 0.98 X 10(-9) M vs. 2.60 +/- 0.62 X 10(-9) M; P less than 0.037). The affinity constant of the ABP was independent of the season (2.45 +/- 0.21 X 10(9) M-1 vs. 2.66 +/- 0.1 X 10(9) M-1; NS). In addition, ABP was positively correlated with 5alpha-DHT (r = 0.506; P less than 0.0009), testosterone (r = 0.445; P less than 0.0003), total protein (r = 0.329; P less than 0.02) and spermatozoa (r = 0.406; P less than 0.006) in the RTF and with blood plasma testosterone (r = 0.584; P less than 0.0001). Furthermore, testosterone and 5alpha-DHT in RTF were positively correlated (r = 0.582; P less than 0.0001). These androgens were also correlated with plasma testosterone (r = 0.262, P less than 0.052 for testosterone in RTF; r = 0.341, P less than 0.018 for 5 alpha-DHT). Total proteins and spermatozoa were found to be positively correlated in the RTF (r = 0.789; P less than 0.0001).

Animals↗