Circadian variation in glucose tolerance and associated changes in plasma insulin and somatostatin levels in normal volunteers.

The day-time variations of blood sugar and associated changes in plasma insulin and somatostatin levels in response to glucose-glucagon load were investigated in eight healthy volunteers. The glucose-glucagon test was performed in the same subjects at 9.00 a.m., at 5.00 p.m. and at midnight after 10 hrs of fasting. The blood sugar values were higher in the midnight while the corresponding plasma insulin levels were significantly lower. Plasma somatostatin levels did not differ at the different times of the day. These results suggest that the circadian variations of the glucose tolerance are correlated to a simultaneous circadian rhythmicity in the insulin response in the sense of a decreased insulin release later in the day. Somatostatin does not seem involved in the circadian variation of beta cell responsiveness observed in healthy volunteers.

Mixed connective tissue disease (Sharp syndrome): description of two cases.

Clinical, neurophysiological, histopathological and immunohistochemical features of two cases of mixed connective tissue disease (Sharp syndrome) are reported.

Epidemiology of diabetes mellitus in an Italian rural community.

To evaluate the prevalence of diabetes in a rural community, 589 subjects in Laurino, Southern Italy, were submitted to a 50 g oral glucose tolerance test. Two hours later, blood glucose levels revealed 453 normal subjects, 36 diabetics and 100 borderline subjects. The borderline subjects were re-examined with 75 g OGTT and, according to criteria recommended by the National Diabetes Data Groups (NDDG), 29 subjects were found normal, 35 with impaired glucose tolerance (IGT) and 36 with diabetes. Final figures showed 72 diabetics (12.2%) and 35 IGT cases (5.9%). Obesity appeared strongly related to diabetes (p less than 0.05 in males and p less than 0.01 in females 40 years old and over). Diabetes was more prevalent in subjects with a positive family history (p less than 0.01). No significant difference in number was observed between male and female diabetics, nor between big babies delivered by normal women and big babies by diabetic women. The high diabetes prevalence might be partly explained by the changes created by an industrially-established dietetic influence on the rural communities in Southern Italy.