Maintenance of permanent sexual activity throughout the year in seasonal bucks using short photoperiodic cycles in open barns.

Seasonality of reproductive activity in rams and bucks is the major constraint in temperate and subtropical zones. Rapid alternation between 1 month of short days and 1 month of long days (LD) over three years in lightproof buildings eliminates this seasonality. We examined if this would also work in open barns, using only supplementary light. Over two years, one group of bucks (n = 7) was subjected to alternate 1 month of LD and 1 month of permanent light (LD-LL) and another group (n = 7) to alternate 1 month of LD and 1 month of natural light (LD-NL). A simultaneous control group, used for both experiments (CG1, n = 6; CG2, n = 6), remained under natural photoperiod. BW, testis weight (TW), plasma testosterone (T) and cortisol (C) were evaluated in all bucks. CG1 and CG2 bucks showed identical dramatic seasonal variations in BW (stable or decreasing in summer), TW (from 85 ± 12 g in February to 127 ± 7 g in July) and T (from 2.7 ± 1.2 ng/mL in January-April to 24.3 ± 3.2 ng/mL in June-October). By contrast, BW of LD-LL and LD-NL bucks increased regularly during the experiment. From 5 and 9 months after the experiment onset, LD-LL and LD-NL bucks, respectively, maintained constant TW of 115 ± 5 g until the experiment end. After the first 3 months <5 ng/mL, T of LD-LL bucks remained constant (5-10 ng/mL) until the experiment end. By contrast, T of LD-NL bucks showed four periods of low (<5 ng/mL) and two periods of high concentrations (18.1 ± 2.6 and 11.9 ± 3.4 ng/mL). Plasma C remained low (5-8 ng/mL) and did not change with group or light treatment. These results show for the first time in any seasonal photoperiodic species that it is possible to maintain the sexual activity of males all year round in open buildings using alternating periods of LD and LL. By contrast, return to NL instead of LL every other month does not prevent seasonality in T concentration. These results raise interesting questions about the photoperiodic control of neuroendocrine regulation of seasonal sexual activity and suggest that these treatments can be used to manage males in open barns in farms and in artificial insemination centres. (Spanish and French versions of the full text are available as Supplementary Materials S1 and S2).

CD4+ CD30+ T cells perpetuate IL-5 production in Dermatophagoides pteronyssinus allergic patients.

BACKGROUND: Airway allergic diseases are regulated by interleukin (IL)-5, which causes infiltration of eosinophils into the bronchial epithelium, and by IL-4 which increases serum immunoglobulin E (IgE) production and promotes CD30 expression on Th cells. CD30 generates a costimulatory signal involved in apoptosis or cell proliferation, depending on the microenvironment. Our aims were: (i) to analyze if CD4+ CD30+ T cells from allergic patients proliferate in response to Dermatophagoides pteronyssinus, and (ii) if upon stimulation this cell population produces IL-4 and IL-5. METHODS: Peripheral blood mononuclear cell (PBMC) from 17 allergic rhinitis and mild allergic asthma patients and 12 healthy nonallergic individuals were stimulated with allergen in the presence or absence of anti-IL-4, anti-IL-5 or anti-IL-4Ralpha monoclonal antibodies (mAbs). TdT-mediated dUTP nick end-labeling (TUNEL) assay, 7-aminoactinomycin-D (7-AAD) intercalation, and flow cytometry were used to determine the CD4+ CD30+ blasts percentage, cell proliferation, apoptosis, and intracellular cytokines after 7 culture days. RESULTS: Cell proliferation induced with allergen showed that 90% of the allergen-stimulated blasts were CD4+, 50% of which were CD30+. Allergen-stimulated PBMC showed a progressive increase (mean: from 7% to 23%) of CD4+ CD30+IFN-gamma+ and CD4+ CD30+IL-4+ blasts which diminished (mean: 6%) after 5 culture days. In contrast, CD4+ CD30+IL-5+ blasts showed a continuous progression (from 12% to 24%) that maintained after 7 culture days. The vast majority of CD4+ CD30+ blasts were negative to 7-AAD or TUNEL. Additionally, a significant decrease (34%) was observed in the number of CD4+ CD30+ blasts when IL-4 was neutralized. CONCLUSIONS: These data suggest that specific allergen stimulation of PBMC isolated from allergic patients generates a nonapoptotic CD4+ CD30+ blast subset that produces IL-5.

Local television news coverage of traumatic deaths and injuries.

OBJECTIVE: To assess how local television news programs' reporting of injuries and deaths from traumatic causes compares with coroners' records of deaths and the estimated incidence of injuries in the same geographic area during the same time. METHODS: Using epidemiologic methods, we identified the underlying cause of death or injury in each of 828 local television news stories broadcast in Los Angeles during late 1996 or early 1997 that concerned recent (<3 days) traumatic injuries or deaths in Los Angeles County. Odds ratios were computed using deaths by homicide or injuries sustained in assaults as the referent group. RESULTS: The number of persons depicted as dead amounted to 47.8% of the actual total number of traumatic deaths occurring in Los Angeles County during the study period. In contrast, the number depicted as injured represented only 3.4% of injuries due to traumatic causes. Both injuries and deaths due to fires, homicides, and legal interventions were proportionally well represented. However, injuries and deaths from accidental poisoning, falls, and suicide were significantly underrepresented. CONCLUSIONS: Some types of events receive disproportionately more news coverage than others. Local television news tends strongly to present only those events concerned with death or injury that are visually compelling. We discuss reasons for concern about the effect that this form of information bias has on public understanding of health issues and possible counteractions that physicians can take.

Lipid status in a population of Spanish schoolchildren.

We assessed lipid status in a population of 181 schoolchildren and adolescents divided into three age groups: 6-7 years (n = 60), 10-12 years (n = 61) and 13-15 years (n = 60). All subjects were from the Mediterranean coastal area of Vélez-Málaga in southern Spain. Nutrient intakes and biochemical parameters related with lipid status [total cholesterol (TC), HDL-chol, LDL-chol, VLDL-chol and triglycerides (TG)] were measured. Boys and girls aged 6-7 years had the same plasma concentrations of TC and TG; these concentrations were slightly higher than the mean values for age and sex found in earlier studies in Spanish populations. The high TC values were due mainly to increased concentrations of LDL-chol. This age group also had the largest percentage of members (26.6% boys, 36.6% girls) with plasma TC above 200 mg/dl. Of the groups aged 10-12 years, more girls than boys had abnormally high plasma cholesterol (16.1 vs 10%), HDL-chol (6.5 vs 0%) and TG concentrations (6.5 vs 0%). However, more adolescent boys than adolescent girls (aged 13-15 years) had abnormally low plasma concentrations of HDL-chol (10 vs 3.3%).

Iron status in a population of Spanish schoolchildren.

Iron status was assessed in a population of 196 schoolchildren and adolescents divided into three age groups: 6-7 years (n = 60), 10-12 years (n = 63) and 13-15 years (n = 73). All subjects were from the Vélez-Málaga area (province of Málaga) in southern Spain. Nutrient intakes and biochemical parameters related with iron status (number of red cells, hematocrit, hemoglobin, serum iron concentration, total iron-binding capacity and transferrin saturation) were measured. The results showed a lack of correlation between the nutrient intake and biochemical findings. Food intake calculations suggested that adolescent girls between 13 and 15 years of age were at greatest risk for iron deficiency (intakes covered only 71.6% and 84% of the iron and folic acid RDAs, respectively), followed by 10-12 year old girls and 6-7 year old boys. However, groups in which iron deficiency was most frequent according to the biochemical data were 6-7 year old boys (10%), followed by 13-15 year old adolescent boys (2.9%).