Twenty-four hour profiles of four hormones under constant routine

Abstract We studied the circadian features of melatonin, cortisol, thyroid stimulating hormone (TSH), and growth hormone (GH) together with rectal temperature during 36 h continuous forced wakefulness without physical exercise under dim light condition (constant routine). Subjects consisted of four healthy men aged 22–24 years. Blood sampling was conducted hourly, and food and water were supplied bi-hourly during the constant routine. Melatonin, TSH and cortisol displayed clear circadian rhythms under constant routine condition. While GH secretion was unlikely to be driven solely by the circadian pacemaker, its suppression round BT nadir may indicate that GH secretion was modulated to some extent by circadian rhythm.     

Quantitative measurements of Hemophilus influenzae type b capsular polysaccharide antibodies in Japanese children

BACKGROUND: Hemophilus influenzae type b (Hib) infection has a high morbidity and mortality rate in children. The frequency of natural immunity against Hib in Japanese children is not known, and Hib vaccine has not yet been introduced in Japan. METHODS: Anti-capsular polysaccharide-specific IgG (anti-CP) antibody titers were examined in serum samples from 100 children and 107 young adults who were not vaccinated against Hib, in serum samples from eight patients with Hib systemic infection and in 10 commercially available human immune globulin preparations on enzyme-linked immunosorbent assay. RESULTS: A total of 44% (44/100) of Japanese children and all patients with Hib systemic infection in the acute phase did not have the minimum protective level of anti-CP antibodies (>0.15 microg/mL). The rate of natural Hib immunity was lowest in children under 1 year of age and gradually increased with age. Only 3.74% (4/107) of Japanese young adults did not have the minimum protective level of anti-CP antibodies. Analysis of 10 commercially available human immune globulin preparations indicated an average level of 28.25 microg anti-CP antibody/mL immune globulin (range 14.96-44.17 microg/mL). CONCLUSIONS: Approximately half of Japanese children are not protected against Hib infection. Therefore, Hib vaccine should immediately be included as part of the routine immunization program in Japan. It was also found that all tested commercially available immune globulin preparations had high anti-CP titers. Well-controlled clinical trials of i.v. immune globulin administration for prevention and treatment of Hib systemic infection are needed in Japan.     

Sirtuin 1 activator SRT1720 suppresses inflammation in an ovalbumin‐induced mouse model of asthma

Background and objective: In asthma, reduced histone deacetylase activity and enhanced histone acetyltransferase activity in the lungs have been reported. However, the precise function of Sirtuin 1 (Sirt1), a class III histone deacetylase, and the effect of the Sirt1 activator SRT1720 on allergic inflammation have not been fully elucidated. Methods: The effect of SRT1720, a synthetic activator of Sirt1, in an ovalbumin (OVA)‐induced asthma mouse model was investigated. The effect of SRT1720 and resveratrol on OVA stimulation in splenocytes from OVA‐sensitized and challenged mice was also examined. Results: In OVA‐sensitized and challenged mice (OVA mice) compared with saline‐sensitized and challenged mice (control mice), Sirt1 messenger RNA expression in the lungs was decreased (P = 0.02), while cellular infiltration, airway eosinophilia and bronchoalveolar lavage (BAL) fluid levels of interleukin (IL)‐4, IL‐5 and IL‐13 were increased (P < 0.01). In OVA mice, SRT1720 treatment decreased total and eosinophil cell counts and IL‐5 and IL‐13 levels in the BAL fluid compared with the vehicle treatment (P < 0.05). In OVA mice, SRT1720 treatment also decreased inflammatory cell lung infiltrates histologically (P = 0.002). Both SRT1720 and resveratrol suppressed OVA‐induced cell proliferation and IL‐6 (P < 0.05) and tumour necrosis factor‐α (TNF‐α) (P < 0.05) production in splenocytes (P < 0.01). Conclusions: The Sirt1 activator SRT1720 suppressed inflammatory cell infiltration and cytokine production in an OVA‐induced mouse model of asthma. SRT1720 and resveratrol suppressed OVA‐induced splenocyte proliferation and TNF‐α and IL‐6 production. Sirt1 activators might have beneficial effects in asthmatics by suppressing inflammation.