Role of the ubiquitin-proteasome system in carotid plaque instability in diabetic patients.

In order to define the role of the ubiquitin-proteasome system in atherosclerotic plaque rupture in patients with type 2 diabetes mellitus (T2DM), we evaluated the amount of this system, of the main inflammatory cells, of the collagen content and some indexes indicative of oxidative stress in the carotid plaques of both diabetic and non-diabetic asymptomatic patients. Plaques were obtained from 31 type 2 diabetic and 27 non-diabetic patients undergoing endoterectomy. Both were examined for macrophages, T-lymphocytes, ubiquitin/proteasome 20S activity, NFkB, IkB-b, nitrotyrosine, matrix metalloproteinase-9 (MMP-9) and collagen. Diabetic plaques had more macrophages,T-lymphocytes, inflammatory cells (HLA-DR), ubiquitin/proteasome, NFkB, nitrotyrosine, MMP-9 and lower collagen content and IkB-b levels, in comparison with non-diabetic plaques. These findings indicate that in diabetic patients, ubiquitin/proteasome overactivity is associated with enhanced inflammatory activity induced by diabetic oxidative stress. This induces the NFkB release into the nucleus which, in turn, is responsible for the expression of inflammatory cytokines causing plaque rupture.

Vigorous exercise acutely changes platelet and B-lymphocyte CD39 expression.

CD39/ATP diphosphohydrolase is expressed on B lymphocytes, cytotoxic T lymphocytes, monocytes, platelets, and endothelial cells, and it has a critical role in the inhibition of platelet responsiveness. To determine whether strenuous exercise could acutely change expression of CD39 in platelets and lymphocytes, eight healthy sedentary men, 34 yr old (SD 7), and eight physically active men, 34 yr old (SD 6), performed graded upright cycle ergometry to volitional exhaustion. Blood samples collected both at baseline and after exercise test were employed to measure CD39 expression in platelets and lymphocytes. The percentage of circulating platelet-platelet aggregates, the "in vitro" ADP and collagen-induced platelet aggregation, and the expression of both platelet glycoprotein IIb-IIIa (PAC-1) and P-selectin (CD62) were also considered markers of platelet activation. After strenuous exercise, all subjects demonstrated significant platelet activation as judged by the increased percentage of platelet-platelet aggregates. The in vitro ADP-induced platelet aggregation and the expression of CD62P on ADP-stimulated platelets significantly increased in sedentary but not in active subjects. After exercise, all of the subjects showed a significant reduction of CD39 expression in platelet [sedentary: from 2.2 (SD 0.8) to 1.1% (SD 0.8), P = 0.008; active: from 0.6 (SD 0.2) to 0.35% (SD 0.1), P = 0.009] and an increase of CD39 expression in B lymphocytes [sedentary: from 47 (SD 13) to 60% (SD 11), P = 0.0039; active: from 46 (SD 11) to 59% (SD 11), P = 0.0038]. Taken together, these findings confirm the critical role of this ADPase in inhibition of platelet responsiveness, also suggesting a possible role of B lymphocytes in thromboregulation mechanism.

Acute hyperglycemia alters von Willebrand factor but not the fibrinolytic system in elderly subjects with normal or impaired glucose tolerance.

To assess whether acute hyperglycemia affects fibrinolytic balance in elderly subjects with normal glucose tolerance (NGT) or impaired glucose tolerance (IGT), 40 non-obese elderly subjects (20 NGT, age 68 +/- 8 years; and 20 IGT, age 69 +/- 11 years) were studied. On two experimental days, randomly allocated and spaced 1 week apart, plasma concentrations of glucose, insulin, fibrinogen, tissue plasminogen activator, plasminogen activator inhibitor type 1 and von Willebrand factor (vWF) were measured in each subject at baseline (0) and 30, 60, 90, 120 min after the ingestion of 75 g glucose or a similarly sweet dose of aspartame (250 mg) (control test). In both NGT and IGT elderly subjects, tissue plasminogen activator, plasminogen activator inhibitor type 1 and fibrinogen plasma levels did not significantly change after both oral aspartame and glucose load. In IGT subjects, vWF plasmatic levels decreased after glucose (not aspartame) oral load, reaching the minimum level at 90 min after load (82.7 +/- 7.8 versus 93.7 +/- 10.2, P <0.01). These results demonstrate that acute hyperglycemia does not modify plasma fibrinolysis in elderly subjects. The decrease of plasma concentration of vWF in IGT elderly subjects requires cautious interpretation and further extensive investigations.

Effects of a moderate-intensity aerobic program on blood viscosity, platelet aggregation and fibrinolytic balance in young and middle-aged sedentary subjects.

Regular physical activity is associated with reduced risk of cardiovascular disease although the mechanisms are unclear. Recent population-based studies suggest that the effect of physical activity may be at least partly a result of action on hemostasis. We tested the hypothesis that moderate-intensity aerobic training improves fibrinolytic activity and reduces platelet aggregation and blood viscosity. In 15 young (11 males and four females; age, 24-32 years) and 15 middle-aged (11 males and four females; age, 45-65 years) healthy, non-smoker, sedentary subjects, the maximum oxygen consumption, adenosine diphosphate-induced platelet aggregation, tissue plasminogen activator and plasminogen activator inhibitor type 1, antigen, hematocrit and blood viscosity were measured at baseline and after 12 weeks of aerobic exercise training (40 min three times a week at a training intensity adjusted to 60% of the individual heart rate reserve). After training, the maximum oxygen consumption was increased by 9% (P < 0.01) in the young group and by 7.3% (P < 0.05) in the middle-aged group. Adenosine diphosphate-platelet aggregation significantly decreased in the young (-30%; P < 0.05). The middle-aged group showed a 10.4% decrease in hematocrit (P < 0.05), and a 11.6 and 16.6% decrease in blood viscosity at 450/s and at 90/s rates of shear, respectively (P < 0.05), while the plasminogen activator inhibitor type 1 antigen plasma level increased 135% (P < 0.01). These data, some not consistent with others, only partially support the hypothesis that the beneficial effects of physical activity result from action on hemostatic balance. In particular, the changes in the fibrinolytic system in middle-aged subjects might suggest increased thrombotic risk. Thus a simple, straightforward conclusion is not possible at present, and further studies are required.

A 69-year-old woman with persistent iron deficiency anemia.

In women, iron deficiency anemia-a result of chronic iron loss-is most common during the reproductive years because of physiologic demands such as menstrual blood losses and pregnancy. In other cases, iron deficiency anemia is generally attributed to occult gastrointestinal bleeding. Common causes of chronic gastrointestinal blood loss include erosive esophagitis, gastric and duodenal ulcers, vascular ectasias, colon adenomas, and cancers. Bleeding from the small intestine at sites beyond the duodenal bulb is uncommon. The lesions of the small intestine are responsible for approximately 4% of gastrointestinal bleeding [7]. In this report we describe a case of persistent iron deficiency anemia due to carcinoid tumor of the small intestine.

Urinary incontinence in the elderly: relation to cognitive and motor function.

Urinary incontinence is a common problem in older subjects, very often wrongfully accepted as a normal part of the aging process. A total of 520 subjects (208 males and 312 females; mean age 74.8 +/- 11.8 years), from both private- and nursing-home dwelling populations, were included in this study aimed to estimate the incidence of urinary incontinence and identify factors associated with condition, in aged subjects. The incidence and type of urinary incontinence (stress, urge or mixed incontinence) were assessed by structured questionnaires and diagnosis was confirmed by a seven-day consecutive voiding diary. Assessment of physical, cognitive and emotional functions was performed on each subject using the Mini Mental State Examination (MMSE), Instrumental Activities of Daily Living Scale (IADL), Tinetti Scale (gait), Tinetti Scale (balance) and Geriatric Depression Scale (GDS) instruments. In the total population sample the incidence of urinary incontinence was 47.9%. The incontinence cases were classified, according to the different types, as: stress incontinence (males: 3.4%; females: 8.7%; males+females: 6.5%); urge incontinence (males: 27.4%; females: 31.4%; males+females: 29.8%); mixed incontinence (males: 20.2%; females: 5.8%; males+females: 11.5%). In the total population sample, no significant relationship was found between age and prevalence of urinary incontinence. In the elderly female group, age significantly correlated in a direct manner with urge incontinence (P<0.01) and inversely with stress incontinence (P<0.001). Only in the male sex group age significantly correlated with mixed incontinence (P<0.005). Multiple linear regression analysis showed that the dependent variable 'incontinence' could be predicted by MMSE (P<0.001) in the male sex group and by the Tinetti Scale (gait) (P<0.001) in the female sex group.