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Obstructive sleep apnoea syndrome (OSAS) is strongly associated with obesity (OB) and is characterized by several changes in endocrine functions, e.g. GH/IGF-I axis, adrenal and thyroid activity. It is still unclear whether these alterations simply reflect overweight or include peculiar hypoxia-induced hormonal alterations. Hormonal evaluations have been generally performed in basal conditions but we have recently reported that OSAS is characterized by a more severe reduction of the GH releasable pool in comparison to simple obesity. We aimed to extend our evaluation of anterior pituitary function to corticotroph, thyrotroph and lactotroph secretion under dynamic testing in OSAS in comparison with simply obese and normal subjects. In 15 male patients with OSAS [age, mean ± SEM 43·5 ± 1·6 years; body mass index (BMI) 39·2 ± 3·1 kg/m2; apnoea/hypopnoea index, (AHI) 53·4 ± 8·7], 15 male patients with simple obesity (OB, age 39·7 ± 1·2 years; BMI 41·2 ± 2·0 kg/m2; AHI 3·1 ± 1·2 events/h of sleep) and in 15 normal lean male subjects (NS, age 38·2 ± 1·4 years; BMI 21·2 ± 0·8 kg/m2; AHI 1·9 ± 0·8 events/h of sleep) we evaluated: (a) the ACTH and cortisol responses to CRH [2 µg/kg intravenously (i.v.)] and basal 24 h UFC levels; (b) the TSH and PRL responses to TRH (5 µg/kg iv) as well as FT3 and FT4 levels. Twenty-four-hour UFC levels in OSAS and OB were similar and within the normal range. Basal ACTH and cortisol levels were similar in all groups. However, the ACTH response to CRH in OSAS (Δpeak: 30·3 ± 3·8 pmol/l; ΔAUC: 682·8 ± 128·4 pmol*h/l) was markedly higher ( P < 0·001) than in OB (Δpeak: 9·3 ± 1·4 pmol/l; ΔAUC 471·5 ± 97·3 pmol*h/l), which, in turn, was higher ( P < 0·05) than in NS (Δpeak: 3·3 ± 0·9 pmol/l; ΔAUC 94·7 ± 76·7 pmol*h/l). On the other hand, the cortisol response to CRH was not significantly different in the three groups. Basal FT3 and FT4 levels as well as the TSH response to TRH were similar in all groups. Similarly, both basal PRL levels and the PRL response to TRH were similar in the three groups. With respect to patients with simple abdominal obesity, obese patients with OSAS show a more remarkable enhancement of the ACTH response to CRH but a preserved TSH and PRL responsiveness to TRH. These findings indicate the existence of a peculiarly exaggerated ACTH hyper-responsiveness to CRH that would reflect hypoxia- and/or sleep-induced alterations of the neural control of corticotroph function; this further alteration is coupled to the previously described, peculiar reduction of somatotroph function. [ABSTRACT FROM AUTHOR]

Hantaviruses belong to the Bunyaviridae family, which is comprised of Bunyavirus, Phlebovirus, Nairovirus, and Hantavirus. Euroasiatic Hantaviruses belong to two distinct subfamilies: Murinae (comprising Hantaan, Dobrava, and Seoul viruses), which are responsible for hemorrhagic fever with renal syndrome (HFRS), and Arvicolinae (comprising Puumala virus), responsible for nephropathia epidemica (NE) and HFRS. On the contrary, the New World Hantavirus belongs to the Sigmodontinae subfamily and includes the North American viruses: Sin Nombre, Monongahela; New York, Bayou, Black Creek Canal, and the South American, which comprise the Andes, Oran, Lechiguanas, Laguna Negra, Juquitiba; both groups are responsible for the hantavirus pulmonary syndrome (HPS). [ABSTRACT FROM AUTHOR]

1 The anti-hypertensive effect of labetalol given twice or three times daily was evaluated in ambulant subjects with essential hypertension by recording blood pressure directly for 24 h before and after 15 d of labetalol administration (daily dose 600-1800 mg). 2 Labetalol reduced 24 h systolic and diastolic blood pressures by about 20%. The reduction was evident throughout the whole 24 h period, although it was less marked during sleep. The hypotensive effect was similar when the drug was given twice or three times daily. 3 The 24 h heart rate was reduced during labetalol treatment. However, this effect was less marked than the hypotensive effect and was not present in all subjects. 4 There was a reduction in the standard deviations of blood pressure and heart rate values. However, in neither case was the coefficient of variation altered, indicating that labetalol did not have any significant effect on the shape of the 24 h blood pressure measurements. [ABSTRACT FROM AUTHOR]