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Thermocutaneous, vascular, metabolic and hormonal changes were investigated during 11 hot flashes from 6 postmenopausal women. The first detectable change was an increase in finger blood flow with a concomitant enhancement of skin conductance. The increase in skin conductance was followed rapidly by a sharp rise in finger temperature. The main endocrine-metabolic changes associated with the above phenomena were a sharp increase in plasma free fatty acids (∼65%), norepinephrine (∼ 100%) and LH (∼20%) levels. Plasma glucose and cortisol tended to be increased but did not reach statistical significance; on the other hand, plasma insulin, glucagon, growth hormone, epinephrine and dopamine remained unchanged.

Lipoprotein(a) (Lp[a]) is generally considered to be a risk factor for the development of cardiovascular disease, but little is known about the possible influence of obesity on the circulating levels of this lipoprotein. The present study was undertaken to examine this aspect in 136 menstrually active women by comparing the serum concentrations of Lp(a) between 72 obese and 64 age-matched nonobese women. Since an adverse effect of androgens and a protective effect of estrogens have been described for plasma lipoprotein profiles in obese women, the relation between the circulating levels of Lp(a) and those of these other hormones was also investigated in obese patients. In addition, other lipoproteins, anthropometric parameters (body mass index and waist-to-hip ratio), and insulin were evaluated. The levels of Lp(a) were not significantly different (Mann-Whitney U test x \ 3-59; p=0.0582 [NS]) between obese (rank sum, 5,367) and control (rank sum, 3,949) women; in addition, the percentage of patients with high Lp(a) levels (cutoff defined at 30 mg/dL) did not differ between the two groups (obese women, 30%; control, 21.8%; x 2 , 0.90; two-sided p=0.341 [NS]). Moreover, no correlation was found between Lp(a) and body mass index. Lastly, when the Lp(a) prevalence odds ratio for obesity was examined by adjusting the levels of this lipoprotein for age, triglycerides, total cholesterol, and high density lipoprotein cholesterol, the probability value (0.88) was far from significant. In obese women, no correlation was found between the logarithmically transformed Lp(a) concentrations and all the other variables evaluated in the study. In conclusion, the present study shows that the circulating levels of Lp ( 1 It is synthesized by the liver 2 and secreted directly into the systemic circulation.

Fibronectin is a high molecular weight alpha-2-glycoprotein. Its peculiar role in the structure of connective tissue, together with its wide involvement in coagulative dynamics, justified the increasing interest for fibronectin in the pathogenesis of diabetic disease and its vascular sequelae. In the present work, we evaluated the levels of plasma fibronectin (PF) in diabetics with and without retinopathy, and studied the possible correlation between the glycoprotein and some hormonal and metabolic parameters, expression of glycometabolic balance. We examined 26 type I and 24 type II diabetics, further divided into retinopathics and not retinopathics, and 43 normal subjects. We did not find any significant difference in PF levels either between normals and diabetics, or between type I and type II patients, or between retinopathics and not retinopathics. PF was significantly correlated to age, both in normals and in diabetics. Diabetic patients showed a significant positive correlation of PF to total cholesterol (r = 0.56; p less than 0.05) and triglycerides (r = 0.36; p less than 0.05). This seems to suggest, although indirectly, the existence of a relationship between the levels of PF and the degree of large vessel involvement. No significant correlation was found with HbA1c, beta-OH, AcAc, lactate, pyruvate, C-peptide, total and free insulin or GH. We further indicated an inverse correlation between PF and plasma glucagon (IRG). Very low levels of PF are commonly associated with high IRG plasma values during acute energy deprivation such as prolonged fasting and ketoacidotic coma. Therefore, PF levels might represent an index of latent to overt energy depletion.

In order to evaluate factors influencing the duration of residual B-cell function in maturity-onset diabetics we investigated 104 patients (age 60 +/- 11 years) with a mean duration of disease of 11.3 +/- 8.7 years by measuring fasting C-peptide (FCP) and fasting blood glucose levels (FBG), C-peptide increment after a standardized breakfast and both mean diurnal plasma glucose (MBG) and mean diurnal C-peptide levels (MCP). C-peptide levels were found to be reciprocally dependent on both the age at onset (positively) and, conversely, on the duration of diabetes (y = 0.75 + 0.026x1-0.049x2; R = 0.52, t1 = 2.76, t2 = -4.08). In particular, the present B-cell secretory capacity appears to be lower the younger the patients were at onset, thus suggesting that inherent impairment of B-cell capacity may play a crucial role in determining age at onset of type II diabetes and thus the duration of their residual B-cell function. Moreover, by analyzing separately the data from patients treated with insulin and oral agents respectively, we found that the influence of the duration of the disease on the rate on B-cell exhaustion is unrelated to the mode of treatment even though B-cell capacity at onset appears to be more severely reduced in insulin-treated subjects who, apart from anything else, were younger at onset.(ABSTRACT TRUNCATED AT 250 WORDS)