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Cumulus-oocyte communications in the horse: role of the breeding season and of the maturation medium.

Horse is a seasonal breeder and information on oocyte quality outside the breeding season is very limited. Ovaries obtained at the slaughterhouse are a convenient but often limited source of oocytes in this species. As the low quantity of ovaries leads to an intensive use of all available material, it would be useful to know whether ovaries collected during the non-breeding season are suitable for in vitro maturation (IVM). In an attempt to characterize the effect of season on oocyte quality, we investigated the permeability of the gap junctions (GJ) present between cumulus cells and oocytes because of their important role in oocyte growth and maturation. We also compared the effect of supplementing the maturation medium with bovine serum albumin (BSA) or oestrus mare serum (EMS). A total of 645 oocytes isolated from 158 and 154 ovaries collected during the breeding and the non-breeding season, respectively, were used in this study. Oocytes were matured for 30 h in TCM 199 supplemented either with 10% EMS or with 4 mg/ml BSA. The presence of permeable GJs between cumulus cells and oocytes was investigated with the injection of a 3% solution of the fluorescent dye Lucifer yellow into the ooplasm. No differences in efficiency of oocyte retrieval or oocyte meiotic competence were detected between oocytes collected during the breeding and non-breeding season. The vast majority (90%) of the oocytes collected during the breeding season had fully functional communications with their surrounding cumulus cells but such communications were completely interrupted in 55.3% of the oocytes collected during the non-breeding season. During the non-breeding season, the proportion of oocytes whose communications with cumulus cells were classified as closed or intermediate at the end of maturation was lower in the group matured with BSA than with EMS (71.4 vs 97.7, p < 0.05). The same trend, although not statistically significant, was observed during the breeding season also. The presence of BSA caused an incomplete cumulus expansion during both seasons. Our data indicate that oocytes collected during the non-breeding season do not show any meiotic deficiency but lack active communication with the surrounding cumulus cells at the time of their isolation from the ovary. No data are available at present for determining the consequences on the developmental competence even if data from other species suggest that this is likely.

Animals↗

Seasonal changes in immune response and parasite impact on hosts.

Seasonal changes in the impact of parasites on hosts should result in seasonal changes in immune function. Since both ectoparasites and endoparasites time their reproduction to that of their hosts, we can predict that hosts have been selected to show an annual peak in their ability to raise an immune response during the reproductive season. We found large seasonal changes in immune function between the breeding and the nonbreeding season for a sample of temperate bird species. These changes amounted to a decrease in spleen mass from the breeding to the nonbreeding season by on average 18% across 71 species and a seasonal decrease in T-cell-mediated immunity by on average 33% across 13 species. These seasonal changes in immune function differed significantly among species. The condition dependence of immune function also differed between the breeding and the nonbreeding season, with individuals in prime condition particularly having greater immune responses during breeding. Analyses of ecological factors associated with interspecific differences in seasonal change of immune function revealed that hole-nesting species had a larger increase in immune function during the breeding season than did open nesters. Since hole nesters suffer greater reduction in breeding success because of virulent parasites than do open nesters, this seasonal change in immune function is suggested to have arisen as a response to the increased virulence of parasites attacking hole-nesting birds.

Aging↗

Seasonal changes in pollinator activity influence pollen dispersal and seed production of the alpine shrub Rhododendron aureum (Ericaceae).

In alpine ecosystems, microscale variation in snowmelt timing often causes different flowering phenology of the same plant species and seasonal changes in pollinator activity. We compared the variations in insect visitation, pollen dispersal, mating patterns, and sexual reproduction of Rhododendron aureum early and late in the flowering season using five microsatellites. Insects visiting the flowers were rare early in the flowering season (mid-June), when major pollinators were bumblebee queens and flies. In contrast, frequent visitations by bumblebee workers were observed late in the season (late July). Two-generation analysis of pollen pool structure demonstrated that quality of pollen-mediated gene flow was more diverse late in the season in parallel with the high pollinator activity. The effective number of pollen donors per fruit (N(ep)) increased late in the season (N(ep) = 2.2-2.7 early, 3.4-4.4 late). However, both the outcrossing rate (t(m)) and seed-set ratio per fruit were smaller late in the season (t(m) = 0.89 and 0.71, seed-set ratio = 0.52 and 0.18, early and late in the season, respectively). In addition, biparental inbreeding occurred only late in the season. We conclude that R. aureum shows contrasting patterns of pollen movement and seed production between early and late season: in early season, seed production can be high but genetically less diverse and, during late season, be reduced, possibly due to higher inbreeding and inbreeding depression, but have greater genetic diversity. Thus, more pollinator activity does not always mean more pollen movement.

Animals↗

Seasonal effects of administration of melatonin and 5-methoxytryptophol on ovarian activity in the catfish Heteropneustes fossilis (Bloch).

In Heteropneustes fossilis, effects of intraperitoneal administration (25 micrograms/fish, alternate days for a month 1 hr before the onset of dark phase) of melatonin (MEL) and 5-methoxytryptophol (5-MTL) on ovarian activity were investigated during different seasons of the annual reproductive cycle under natural photothermal conditions. The gonadosomatic index (GSI) had decreased significantly by MEL during preparatory and prespawning seasons, and by 5-MTL in all but the spawning season. Both MEL and 5-MTL administrations arrested vitellogenesis during the gonadal recrudescence phase. As a result, stage I previtellogenic oocytes showed a significant increase in the MEL group in the preparatory and prespawning seasons, and in the 5-MTL group only in the prespawning season. Almost the same trend was noticed in the percentage distribution of stage 2 and 3 oocytes. The percentage distribution of stage 4 postvitellogenic oocytes decreased significantly during the preparatory and prespawning seasons, but not in the spawning season. The indole treatment resulted in a highly significant increase in the percentage distribution of atretic oocytes during prespawning, spawning, and post-spawning phases. Total protein content of the ovary was significantly lower in all seasons after MEL treatment, and only in the preparatory and prespawning seasons following 5-MTL treatment. The ovarian glycogen level was significantly lower in the preparatory and prespawning seasons (MEL group), and in the 5-MTL group only in the prespawning phase. Ascorbic acid level was inhibited by the indole treatment in all seasons except in the 5-MTL group during the post-spawning season. The results show that both MEL and 5-MTL are effective in inhibiting ovarian vitellogenesis and inducing atresia in the catfish.

Animals↗

Previous injury as a risk factor for injury in elite football: a prospective study over two consecutive seasons.

BACKGROUND: Previous injury is often proposed to be a risk factor for football injury, but most studies rely on players reporting their own medical history and are thus potentially subject to recall bias. Little is known about the natural variation in injury pattern between seasons. OBJECTIVES: To study whether prospectively recorded injuries during one season are associated with injuries sustained during the following season, and to compare injury risk and injury pattern between consecutive seasons. METHODS: The medical staffs of 12 elite Swedish male football teams prospectively recorded individual exposure and time loss injuries over two full consecutive seasons (2001 and 2002). A multivariate model was used to determine the relation between previous injury, anthropometric data, and the risk of injury. RESULTS: The training and match injury incidences were similar between seasons (5.1 v 5.3 injuries/1000 training hours and 25.9 v 22.7/1000 match hours), but analysis of injury severity and injury patterns showed variations between seasons. Players who were injured in the 2001 season were at greater risk of any injury in the following season compared with non-injured players (hazard ratio 2.7; 95% confidence interval 1.7 to 4.3, p<0.0001). Players with a previous hamstring injury, groin injury, and knee joint trauma were two to three times more likely to suffer an identical injury in the following season, whereas no such relation was found for ankle sprain. Age was not associated with an increased injury risk. CONCLUSIONS: This study confirmed previous results showing that previous injury is an important risk factor for football injury. Overall injury incidences were similar between consecutive seasons, indicating that an injury surveillance study covering one full season can provide a reasonable overview of the injury problem among elite football players in a specific environment. However, a prolonged study period is recommended for analyses of specific injury patterns.

Adolescent↗

Specific immunoglobulin E, interleukin-4, and soluble vascular cell adhesion molecule-1 in sera in patients with seasonal allergic rhinitis.

This study included 23 nonatopic volunteers and 84 patients with seasonal allergic rhinitis due to Japanese cedar pollen. Serum interleukin-4 (IL-4) and soluble vascular cell adhesion molecule-1 (sVCAM-1) in the patients were significantly higher than those in the nonatopic individuals, even outside of the pollen season. Both the good responders and the poor responders to antihistamine tablets showed significant increases in IL-4 and specific IgE during the pollen season, whereas such seasonal increases were not observed in the good responders to immunotherapy. Seasonal increases in IL-4 were significantly correlated with those of specific IgE. However, seasonal increases in sVCAM-1 were not significant. Seasonal increases in sVCAM-1 were not significantly different between the good responders and the poor responders to pharmacotherapy or immunotherapy. In conclusion, serum IL-4 and sVCAM-1 are increased in patients with seasonal allergic rhinitis, even outside of the pollen season; this finding might suggest underlying preponderant in vivo activation of T helper cell-2-like cells and inflammatory events in seasonal allergic rhinitis. A seasonal increase in IL-4 in sera might be at least partly involved in the seasonal increase in specific IgE in sera. Immunotherapy's inhibitory effect on IL-4 production and specific IgE response might be one of its working mechanisms.

Adult↗

Composition of seasonality of disease.

The composition of the seasonality of total death was ascertained. Vascular disease seasonality constitutes more than half. The remaining seasonality is influenced by respiratory disease. Surprisingly and of possible importance cancer mortality was not seasonal. Deaths from 'all other disease' and from 'injuries' is seasonal. Seasonality increases with age. In coronary and cerebrovascular disease death has a large seasonal fluctuation. On the other hand hospital admissions and survivors have a minor seasonal fluctuation--only cerebrovascular admissions reaching the chosen level of significance with a small seasonal amplitude. For vascular disease the ranking of seasonal fluctuation from greatest to least is--death outside hospital, total death, death inside hospital, admissions, survivors. It is death outside hospital presumably 'sudden' that imposes seasonality on coronary disease in general. For respiratory diseases not only death but hospital admissions and survivors have high amplitude seasonality with a much greater fluctuation than for death in vascular disease.

Aged↗

Hormone ontogeny in the ovine fetus and neonatal lamb. XX. Effect of age, breeding season, and twinning on the growth hormone (GH) response to GH-releasing factor: evidence for a homeostatic role of fetal GH.

The ovine GH (oGH) response to GRF (1-44 amide) was evaluated in 74 chronically catheterized fetal and neonatal lambs. After a 1-h control period, GRF was administered iv, and the oGH response was studied during the next 60 min. The following variables were analyzed: GRF dose, fetal or neonatal age, breeding season, and singleton or multiple pregnancy. One and 10 micrograms/kg GRF elicited a similar oGH response, which was greater (P less than 0.001) than the response to 0.1 microgram/kg GRF. GRF-stimulated oGH release was strikingly age dependent. The mean peak incremental oGH response in fetuses of 89-122 days gestation (294 +/- 55 ng/ml) was higher (P less than 0.05) than that in fetuses of 127-145 days gestation (136 +/- 19 ng/ml); the fetal response was much greater (P less than 0.005) than the mean peak increment in neonatal lambs (46 +/- 7 ng/ml). A remarkable difference in basal and GRF-induced oGH secretion was observed in both fetuses and lambs of ewes bred in the normal breeding season (on-season) and those bred out of season (off-season). In the neonatal lamb, the mean basal oGH concentration was higher (P less than 0.005) in the on-season (12 +/- 2 ng/ml) than in the off-season (7 +/- 0.5 ng/ml) neonatal lambs, as was the mean peak incremental oGH response to GRF (70 +/- 12 vs. 33 +/- 7 ng/ml; P less than 0.01). In contrast, in singleton, late gestational fetuses (127-145 days), the mean basal oGH concentration was lower (P less than 0.03) in the on-season (74 +/- 9 ng/ml) than in the off-season (124 +/- 18 ng/ml) fetuses, as was the mean peak incremental oGH response to GRF (136 +/- 9 vs. 292 +/- 41 ng/ml; P less than 0.005). Further, compared to the on-season, late gestational singletons, on-season twin fetuses had higher (P less than 0.0001) basal oGH levels (199 +/- 19 ng/ml) and peak incremental oGH responses (248 +/- 11 ng/ml). Moreover, off-season twin fetuses had the highest basal GH concentrations and the most striking increment in GH concentration after GRF treatment of any of the groups. The strikingly age-dependent pattern of the GRF-induced oGH response in fetal and neonatal lambs is compatible with the concept that the inhibitory influences or their effects on the somatotrope increase gradually during late gestation and sharply at birth.(ABSTRACT TRUNCATED AT 400 WORDS)

Aging↗

Seasonal cycles in the blood plasma concentration of FSH, inhibin and testosterone, and testicular size in rams of wild, feral and domesticated breeds of sheep.

Seasonal cycles in testicular activity in rams were monitored in groups of wild (mouflon), feral (Soay) and domesticated breeds of sheep (Shetland, Blackface, Herdwick, Norfolk, Wiltshire, Portland and Merino) living outdoors near Edinburgh (56 degrees N). The changes in the blood plasma concentrations of FSH, inhibin and testosterone, and the diameter of the testis were measured every half calendar month from 1 to 3 years of age. There were significant differences between breeds in the magnitude and timing of the seasonal reproductive cycle. In the mouflon rams, the seasonal changes were very pronounced with a 6-15-fold increase in the plasma concentrations of FSH, inhibin and testosterone from summer to autumn, and a late peak in testicular diameter in October. In the Soay rams and most of the domesticated breeds, the seasonal increase in the reproductive hormones occurred 1-2 months earlier with the peak in testicular size in September or October. In the two southern breeds (Portland and Merino), the early onset of testicular activity was more extreme with the seasonal maximum in August. In cross-bred rams, produced by mating Soay ewes (highly seasonal breed) with Portland or Merino rams (less seasonal breeds), there was a seasonal reproductive cycle that was intermediate compared to that of the parents. A comparison between all 11 breeds showed a significant correlation between the timing of the seasonal cycle in plasma FSH concentration and testicular diameter (time of peak FSH vs testis, r = 0.95). The overall results in the rams are consistent with a primary role of FSH in dictating the seasonal cycle in testicular size and the secretion of inhibin. The earlier seasonal onset in the testicular cycle in the southern breeds of domesticated sheep, and the differences from the wild type, are taken to represent the effects of genetic selection for a longer mating season.

Animals↗

Crossbred and purebred dairy cattle in warm and cool seasons.

This study was to determine if breed groups ranked differently in warm (May to August) and cool (November to February) seasons of calving and to determine if heterosis was more important in the warm season. A total of 719 records of cows in first lactation in four herds in the southeastern United States were used. Breeds were Holsteins, Brown Swiss, and Jerseys and the crosses among them. Milk and milk fat yields were greater in the cool season than in the warm season. Holsteins exceeded other breeds for milk and milk fat yield in both seasons, but their superiority was less among cows calving from May through August. Days open were longer for Holsteins, particularly in the warm season. In the cool season only the 3/4 Holstein X 1/4 Swiss group exceeded Holsteins for milk, but two groups--1/2 Holsteins X 1/2 Swiss and 5/8 Holstein X 1/4 Swiss-1/8 Jersey--were higher in the warm season. In the cool season three crossbred groups--1) 1/2 Holstein X 1/2 Swiss (Holstein sires), 2) 3/4 Holstein X 1/4 Swiss, and 3) 1/2 Holstein X 1/4 Swiss-1/4 Jersey--had greater milk fat yields than Holsteins, and a fourth--1/2 Holstein X 1/2 Jersey--yielded an equal amount. In the warm season six of the eight crossbred groups had greater milk fat yields than Holsteins. More crossbreds exceeded Holsteins in the warm than in the cool season, suggesting interactions for yields. There was slightly more heterosis in warm than in cool seasons for all traits.

Animals↗

Estrus response of indigenous Nigerian Zebu cows after prostaglandin F2 alpha analogue treatment under continuous observations for two seasons.

The study was undertaken to determine the estrus response pattern of Zebu cows indigenous to Nigeria following treatment with prostaglandin F2alpha analogue and to determine the effect of season on the estrus parameters. Eighty cyclic Zebu cows were used in both the dry and wet seasons. Two single intramuscular injections of 25 mg of PGF2alpha analogue were given per cow 11 days apart regardless of the stage of the estrous cycle. The cows were then observed continuously for 168 h following each injection. The proportion of treated cows responding to PGF2alpha treatment in the wet season (90%) was significantly higher (P<0.005) than in the dry season (70.0%). The mean post-injection interval to onset of non-standing estrus (mucus discharge) was 30.6 h and 28.5 h in the dry and wet seasons, respectively. Similarly, the intervals to standing estrus were 69.7 h and 63.9 h in the two seasons, respectively. Seasonal effects were not significant. The duration of non-standing estrus was similar for the two seasons (164.2 h and 162.0 h) while the duration of standing estrus was significantly (P<0.01) longer in the wet season (19.2 h) than in the dry season (12.6 h). Also there was seasonal influence on the body condition score of cows, the palpability of corpora lutea (CL) and the intensity of estrus as determined by the number of mounts (17.9+/-2.0 and 51.2+/-3.4 mounts per cow per estrus period in the dry and wet seasons, respectively).

Journal Article↗

Sport-seasonal changes in body composition, growth, power and strength of adolescent wrestlers.

Changes in body composition, somatic growth, power and strength of high school wrestlers (W, n = 8, 15.9 +/- 0.3 yrs) and controls (C, n = 6, 16.1 +/- 0.2 yrs) were studied early, mid-, late-, and 3.5-months post-season. Elbow flexion peak power (FPP), peak torque (FPT), extension peak power (EPP), and peak torque (EPT) were measured on an isokinetic dynamometer. C demonstrated normal rates of somatic growth and gains in strength and power. However, for W, significant (p < 0.05) decreases were found in: weight (WT, 61.6 +/- 2.8 to 59.2 +/- 2.8 kg), relative fat (%BF) (7.8 +/- 0.7 to 6.1 +/- 0.7 %), FPT (33.3 +/- 2.3 to 29.9 +/- 2.7 Nm), FPP (125.8 +/- 0.3 to 107.8 +/- 8.4 W), EPT (37.5 +/- 2.5 to 36.2 +/- 3.8 Nm), and EPP (132.7 +/- 8.4 to 126.7 +/- 12.3 W), between early-season and late-season and significant increases in WT (5.4 +/- 0.4 kg), fat-free mass (FFM, 4.4 +/- 0.7 kg), FPT (9.4 +/- 1.7 Nm), FPP (38.8 +/- 8.8 W), EPT (6.5 +/- 1.0 Nm), and EPP (24.4 +/- 4.7 W), between late-season and post-season. Compared to C, W had significantly (p < 0.05) smaller increases in mid-arm girth and flexed mid-arm cross-sectional muscle area (X-SECT) during the wrestling season and larger increases in shoulder girth, abdominal girth, and mid-arm girth, X-SECT, and biacromial, biilium, and anterior-posterior chest breadths during the post-season. Power and strength measures were significantly correlated with FFM, lean upper limb volume (ULV), and X-SECT (r = 0.74 to 0.93, p <0.0001). When covaried for FFM, ULV or X-SECT seasonal declines in strength and power were no longer significant while post-seasonal increases remained. In conclusion, pre- to late- season W demonstrated a lack of lean tissue accretion and reductions in strength. At post-season these variables returned to, or were above, pre-season levels. Results of analysis of covariance indicated that lean tissue changes were associated with the changes in strength and power.

Adolescent↗

Prevention of anterior cruciate ligament injuries in female team handball players: a prospective intervention study over three seasons.

OBJECTIVE: To assess the effect of a neuromuscular training program on the incidence of anterior cruciate ligament injuries in female team handball players. DESIGN: Prospective intervention study. SETTING: Female team handball: Division I-III in Norway. PARTICIPANTS: Players from the three top divisions: control season (1998-1999), 60 teams (942 players); first intervention season (1999-2000), 58 teams (855 players); second intervention season (2000-2001), 52 teams (850 players). INTERVENTION: A five-phase program (duration, 15 min) with three different balance exercises focusing on neuromuscular control and planting/landing skills was developed and introduced to the players in the autumn of 1999 and revised before the start of the season in 2000. The teams were instructed in the program and supplied with an instructional video, poster, six balance mats, and six wobble boards. Additionally, a physical therapist was attached to each team to follow up with the intervention program during the second intervention period. MAIN OUTCOME MEASURES: The number of anterior cruciate ligament injuries during the three seasons and compliance with the program. RESULTS: There were 29 anterior cruciate ligament injuries during the control season, 23 injuries during the first intervention season (OR, 0.87; CI, 0.50-1.52; p = 0.62), and 17 injuries during the second intervention season (OR, 0.64; CI, 0.35-1.18; p = 0.15). In the elite division, there were 13 injuries during the control season, six injuries during the first intervention season (OR, 0.51; CI, 0.19-1.35; p = 0.17), and five injuries in the second intervention season (OR, 0.37; CI, 0.13-1.05; p = 0.06). For the entire cohort, there was no difference in injury rates during the second intervention season between those who complied and those who did not comply (OR, 0.52; CI, 0.15-1.82; p = 0.31). In the elite division, the risk of injury was reduced among those who completed the anterior cruciate ligament injury prevention program (OR, 0.06; CI, 0.01-0.54; p = 0.01) compared with those who did not. CONCLUSIONS: This study shows that it is possible to prevent anterior cruciate ligament injuries with specific neuromuscular training.

Adult↗

Prospective study of change in patellar tendon abnormality on imaging and pain over a volleyball season.

OBJECTIVE: Patellar tendon injury, defined by tendon abnormality (TA) on imaging and by pain, is common among volleyball players, but little is known about change in this injury over a volleyball season. Increased activity in the season compared with the off season may result in the development of TA and/or pain. This study investigated the behaviour of TA and pain over a competitive volleyball season. METHODS: Tendon abnormality and pain were measured in 101 volleyball players at the beginning and end of a season. Pain was measured with the single leg decline squat test, which loads the patellar tendon, and TA was detected with ultrasound imaging. Hours of weekly activity were measured and compared during the season and the off season. The proportion of tendons that underwent development and resolution in TA and/or pain over the season was investigated. RESULTS: Hours of weekly activity was greater during the season than in the off season. Most of the tendons investigated (66.3%) did not undergo a change in TA or pain over the season. Tendon abnormality and/or pain developed in 16.6% of tendons and resolved in 11.2%. CONCLUSIONS: The tendons of volleyball players respond variably to the increased load over the season. Change in TA and pain does not appear to be entirely dependent upon load.

Adult↗

[Tear eosinophil cationic protein measurement in patients with seasonal allergic conjunctivitis].

PURPOSE: In the patients with seasonal allergy conjunctivitis (SAC), we investigated the concentration of tear eosinophil cationic protein (ECP) levels, the diagnosis of SAC and the usefulness of studying the disease states. SUBJECTS AND METHODS: The subjects were patients suffering from conjunctivitis seasonal allergy caused by cedar pollen and a healthy control group, and the study period was three years from 2001 to 2003. We divided the allergy group into 27 eyes of 27 patients that we measured before the pollen season and 44 SAC eyes of 44 patients that we measured during the pollen season. The healthy control group was 23 eyes of 23 healthy adults. Tears were collected by the schirmer I method. The ECP value of specimens was measured by enzyme-linked immunosorbent assay (ELISA) using samples which we eluted in buffer (0.5 M NaCl + 0.5% tris buffer saline with Tween 20) from Schirmer test paper. RESULTS: The measurement range of ELISA was 3.6-180 microg/l. The mean ECP value above the lower limit of ELISA in tears was 5.06 +/- 3.39 microg/l (n = 7) (mean +/- standard deviation) for the healthy control group, 9.32 +/- 6 .68 (n = 11) for the preseason group, and 54.90 +/- 117.74 (n = 29) for the pollen season group. The difference between the healthy group and the seasonal group was highly significant (p < 0.005), but there was no significant difference between the healthy group and the preseason group. We set the cut-off point at the 95th percentile (11.1 microg/l) of the healthy group and considered any value above cut-off as positive. The ECP value was positive in 2.5% (3 eyes out of 27) in the preseason group and 40.9% (18 of 44) in the seasonal group, and there was a significant difference (p < 0.01) between the seasonal group and the healthy group. When the seasonal group was divided into patients who had started treatment before the pollen season and those who began treatment during the season, we found a small ECP difference, but it was not statistically significant. CONCLUSION: Measurement of the ECP value in seasonal pollen allergy sufferers may be useful for pathological ascertainment, but it dose not provide adequate diagnosis because of the large number of false negative cases.

Adult↗

Dimensional measurement of seasonal variation in mood and behavior.

Recent epidemiologic studies have found that the behaviors that characterize seasonal affective disorder (SAD) show seasonal variation in 92%-95% of the general population, suggesting that seasonal variation in behavior and mood is a continuous, dimensional variable extending throughout the general population, defined at the upper extreme by SAD. Research into population seasonality will require a dimensional measure of seasonal variation in mood and behavior that produces a broad, finely graded distribution of seasonality scores sensitive to individual differences throughout the entire range of scores. Accordingly, the Inventory of Seasonal Variation (ISV) was developed as such a measure. This study demonstrated that the ISV has high internal structural validity and is highly sensitive to individual differences in seasonality across its entire range of scores in the normal population. This latter characteristic is not shared by other existing measures of seasonality. Initial external validity of the ISV was supported in that the mean of ISV scores of a SAD sample was found to lie at the 97th percentile of the normal population of scores. Analysis of ISV scores revealed that a winter pattern of seasonality was reported by over 95% of subjects, a pattern that was more pronounced in women than men, while a summer type of seasonality was reported by only 0.6% of the general population.

Adult↗

Analysis of exhaled leukotrienes in nonasthmatic adult patients with seasonal allergic rhinitis.

BACKGROUND: Leukotrienes (LTs) are increased in exhaled breath condensate (EBC) in patients with asthma. So far no data have been reported about LT levels in nonasthmatic patients with seasonal allergic rhinitis (SAR). The aim of the study was to find out whether the LT levels in EBC were increased in the nonasthmatic adult patients with SAR both during and after the pollen season in comparison with healthy controls and to assess the changes of the LT levels after the pollen season. METHODS: Twenty-nine nonasthmatic adult patients with SAR underwent measurement of exhaled LTs in the EBC during and after the pollen season. Leukotrienes B(4), C(4), D(4) and E(4) were analysed by a specific and sensitive gas chromatography/mass spectrometry (GC/MS) assay and compared with 50 healthy nonsmoking controls. Spirometry, skin prick tests and nonspecific IgE were evaluated. RESULTS: Leukotrienes concentrations (B(4), E(4) but not D(4)) were significantly increased in and after the pollen season in patients with SAR in comparison with healthy controls. In most of the samples, LT C(4) was undetectable. The values of all exhaled LTs were significantly decreased after the pollen season compared with the seasonal baseline: LTB(4) (P = 0.023), LTD(4) (P = 0.020), LTE(4) (P = 0.047). CONCLUSIONS: Levels of exhaled LTB(4) and LTE(4) were higher in SAR patients than in healthy controls and decreased after the pollen season as compared with levels in season. The SAR patients with the highest in season LT levels had also the post-season levels elevated and this may be an early marker of inflammatory process in the lower airways despite the absence of clinical symptoms of asthma.

Adolescent↗

Comparison of nasal immunohistology in patients with seasonal rhinoconjunctivitis treated with topical steroids or specific allergen immunotherapy.

BACKGROUND: Specific allergen immunotherapy (SIT) and nasal steroids (NS) are considered effective anti-inflammatory treatments for allergic rhinitis, although their mechanism of action differs. OBJECTIVE: The aim of this study was to examine the effect of treatment with NS and SIT on different populations of inflammatory cells in the nasal mucosa and to compare cell numbers before and during the birch pollen season in patients with seasonal allergic rhinitis. METHODS: In a randomized, double-blind, double dummy comparative study, 41 patients with seasonal rhinoconjunctivitis were treated with birch SIT or NS (budesonide 400 microg daily). Treatment with NS started before the birch pollen season and at the same time SIT-treated patients reached the maintenance dose. Nasal biopsies for immunohistochemistry were obtained before the season and start of the treatments and at the peak of the pollen season during treatment. RESULTS: Symptoms of rhinoconjunctivitis increased significantly in both groups during the pollen season but less in the NS-treated group and the difference between the treatment groups was significant at the end of the season (P = 0.03). Immunohistochemistry of nasal biopsies from NS-treated patients showed significantly fewer CD1a+, IgE+ and Fc epsilonRI+ cells during the season compared with preseason (P = 0.02, P = 0.001 and P = 0.0004, respectively) and with seasonal values of the SIT-treated group (P = 0.002, P = 0.002 and P = 0.0004 respectively). CONCLUSION: Treatment with NS but not SIT decreased the numbers of CD1a+, IgE+ and Fc epsilonRI+ cells during the birch pollen season. Our data indicate that treatment with NS has a broader anti-inflammatory range than SIT.

Administration, Topical↗