Demographic, clinical and antibody characteristics of patients with digital ulcers in systemic sclerosis: data from the DUO Registry

OBJECTIVES: The Digital Ulcers Outcome (DUO) Registry was designed to describe the clinical and antibody characteristics, disease course and outcomes of patients with digital ulcers associated with systemic sclerosis (SSc). METHODS: The DUO Registry is a European, prospective, multicentre, observational, registry of SSc patients with ongoing digital ulcer disease, irrespective of treatment regimen. Data collected included demographics, SSc duration, SSc subset, internal organ manifestations, autoantibodies, previous and ongoing interventions and complications related to digital ulcers. RESULTS: Up to 19 November 2010 a total of 2439 patients had enrolled into the registry. Most were classified as either limited cutaneous SSc (lcSSc; 52.2%) or diffuse cutaneous SSc (dcSSc; 36.9%). Digital ulcers developed earlier in patients with dcSSc compared with lcSSc. Almost all patients (95.7%) tested positive for antinuclear antibodies, 45.2% for anti-scleroderma-70 and 43.6% for anticentromere antibodies (ACA). The first digital ulcer in the anti-scleroderma-70-positive patient cohort occurred approximately 5 years earlier than the ACA-positive patient group. CONCLUSIONS: This study provides data from a large cohort of SSc patients with a history of digital ulcers. The early occurrence and high frequency of digital ulcer complications are especially seen in patients with dcSSc and/or anti-scleroderma-70 antibodies

Thermoregulation in precocial avian embryos

Oxygen consumption was measured and heat production (HP) calculated in Muscovy Duck (Cairina moschata) and Domestic Fowl (Gallus gallusf domestica) embryos at different ambient temperatures (Ta) using a closed (Scholander-method) or a halfopen system connected to a paramagnetic oxygen analyzer (Magnos, Hartmann and Braun, Germany) . After internal pipping, respiratory rate, respiratory tidal volume and minute volume as well as blood flow in the chorioallantoic membrane were estimated in a number of embryos at 40°C. Simultaneously, the temperature of the allantoic fluid (Taf) and colonic temperature (Tc) were measured . In other experiments, Muscovy Duck embryos were incubated at Ta of 34.5 ° C and HP was compared at different Ta with that of birds incubated at 37.5 °C. Generally, a decrease in Ta led to a decrease in Tc, Taf and HP. The estimated HP is the result ofthe depressing influence of the Q10 -effect and the positive influence of CNS-controlled thermoregulatory HP. The older the embryo, the lower the minimal Q10 obtained, the lower the threshold Taf for a Q10 of 2.0 and the higher the Taf at the minimal Q10. The results suggest that endothermic reactions in precocial birds occur very early during embryonic development . Prenatal temperature experiences seem to stimulate thermoregulatory HP of embryos. During the period between internal and external pipping, panting occurred with increasing body temperature and, in Muscovy Duck embryos, the respiratory rate increased in the Tc-zone between 38.5 and 40 .5 °C. It seems to be that many organ functions occur during embryonic development, before these functions are ultimately necessary to ensure the survival of the embryo . Prenatal activation of functional systems may have a training effect on the postnatal efficiency of the related adaptive mechanisms

Development of avian thermoregulatory system during the early postnatal period: development of the thermoregulatory set-point

The development of colonic temperature and of heat production in 1- to 10-d-old chicken, turkeys and Muscovy ducklings was investigated after short-term (l h) exposure in climatic chambers to ambient temperatures between 10 and 40°C. In additional experiments the development of colonic temperature and preferred ambient temperature was studied in a temperature gradient tunnel (ambient temperature range 10- 45 ° C). The decrease in biological optimum temperature (identical with the ambient temperature at which the organism is exposed to minimal thermal load) and in the preferred ambient temperature with increasing age indicated that the lower colonic temperature during the first days after hatching is caused by changes of the thermoregulatory set-point . Compared with normally incubated ducklings, an incubation temperature (34 .5 °C) lower than the usual 37 .5 °C during the last week of embryonic development may induce a lower thermoregulatory set-point. These birds have a higher postnatal cold tolerance, they prefer lower ambient temperatures and have a higher heat production at low ambient temperatures at the first day post-hatching