The C825T GNB3 polymorphism, independent of blood pressure, predicts cerebrovascular risk at a population level

BACKGROUND

The role of C825T polymorphism of the candidate GNB3 gene in predicting cerebrovascular outcome has been poorly explored in longitudinal setting at a population level.

METHODS

In an epidemiological setting, 1,678 men and women from general population were genotyped for C825T polymorphism of GNB3 gene and follow-up for 10 years to detect nonfatal and fatal cerebrovascular events (CE). Established cerebrovascular risk factors were used to adjust the multivariate Cox analysis for confounders.

RESULTS

Seventy-three nonfatal and 30 fatal CE were recorded. Incidence of CE was higher in TT than in C-carriers (fatal: 2.6 vs. 1.7%, P < 0.03; nonfatal: 7.8 vs. 3.9%, P < 0.03; fatal recurrences: 1.6 vs. 0.6%, P < 0.03). In Cox analysis, the TT genotype predicted nonfatal (hazard ratio 1.99, 95% confidence interval 1.05-3.79, P = 0.03), fatal (2.91, 1.05-8.12, P = 0.04), and fatal recurrent CE (6.82, 1.50-31.1, P = 0.02) also after adjustment for age, gender, systolic and diastolic blood pressure, body adiposity, atherogenetic blood lipids, serum uric acid, diabetes, calories, caffeine and ethanol intake, and coronary events at baseline. Further adjustment for historical CE made the association between TT genotype and incident fatal CE nonsignificant (hazard ratio 2.72, 95% confidence interval 0.96-7.22, P = 0.06).

CONCLUSIONS

The TT genotype of GNB3 gene predicts incident CE independent of blood pressure and other established risk factors at a population level. Further studies are needed to clarify the nature and pathways of this association.

Glycaemic fall after a glucose load. A population-based study

BACKGROUND AND AIMS

A blood glucose (BG) fall after an oral glucose load has never been described previously at a population level. This study was aimed at looking for a plasma glucose trend after an oral glucose load for possible blood glucose fall if any, and for its impact on coronary mortality at a population level.

METHODS AND RESULTS

In subjects from an unselected general population, BG and insulin were detected before and 1 and 2h after a 75-g oral glucose load for insulin sensitivity and β-cell function determination. Blood pressure, blood examinations and left ventricular mass were measured, and mortality was monitored for 18.8±7.7 years. According to discriminant analysis, the population was stratified into cluster 0 (1-h BG < fasting BG; n=497) and cluster 1 (1-h BG ≥ fasting BG; n=1733). To avoid any interference of age and sex, statistical analysis was limited to two age-gender-matched cohorts of 490 subjects from each cluster (n=940). Subjects in cluster 0 showed significantly higher insulin sensitivity and β-cell function, lower visceral adiposity and lower blood pressure values. Adjusted coronary mortality was 8 times lower in cluster 0 than 1 (p<0.001). The relative risk of belonging to cluster 1 was 5.40 (95% CI 2.22-13.1).

CONCLUSION

It seems that two clusters exist in the general population with respect to their response to an oral glucose load, independent of age and gender. Subjects who respond with a BG decrease could represent a privileged sub-population, where insulin sensitivity and β-cell function are better, some risk factors are less prevalent, and coronary mortality is lower.

Expression and Phosphorylation of Protein Kinase C Isoforms in Aβ1–42 Activated T Lymphocytes from Alzheimer's Disease

The protein kinase C (PKC) family of enzymes is a regulator of transmembrane signal transduction. There is evidence demonstrating altered activity of some PKC isoforms (PKC-α, PKC-δ and PKC-ζ) in the neurons of brains of Alzheimer's Disease (AD) sufferers, but little is known about their involvement in the intracellular machinery of amyloid β protein-reactive T lymphocytes in AD. By applying a modified “split-well culture system” for Aβ1–42 reactivity, we carried out flow cytometry analysis and biochemical investigations on the possible involvement of PKC-α, PKC-δ and PKC-ζ in the signalling system activated in Aβ-reactive T cells purified from peripheral blood mononucleate cells (PBMC) from healthy subjects and patients with AD. Flow cytometry analysis of Aβ1–42 activated T lymphocytes in the majority of AD patients highlighted a distinct cellular cluster highly expressing phospho-PKC-δ (P-PKC-δ), while most full-blown AD patients highly expressed two distinct P-PKC-δ and phospho-PKC-ζ (P-PKC-ζ) bright sub-populations. The same investigation performed in freshly purified peripheral T lymphocytes, did not highlight any subpopulation, suggesting that the detection of P-PKC-δ and P-PKC-ζ bright subpopulations is specifically linked to Aβ1–42 activated T lymphocytes. The data presented here, therefore, suggest possible novel hallmarks to discriminate between healthy elderly subjects and beginning or full-blown Alzheimer's Disease patients.

Nuclear protein kinase C-delta: a possible check-point of cell cycle progression

Protein kinase Cs (PKCs) belong to a serine/threonine kinase family, ubiquitously expressed and claimed to be involved in physiological processes including apoptosis, cell growth and differentiation. The question of the subcellular localization and activity of PKCs remains to be clarified. Here we report that nuclear PKC-delta cooperates to regulate the S-G2/M phase transition of cell cycle, apparently being associated to chromosome condensation and alignment on the metaphase plate.

[Maintenance therapy: an indispensible complement to periodontal treatment and the surgical implant]

The authors analyze the literature of recent years on maintenance therapy both in parodontopathic patients and in subjects undergoing surgical implantation therapy. We divide the work in two parts; the first shows the general aspects of maintenance therapy, the second shows the specific aspects of maintenance therapy in non surgical parodontal treatment, in after surgical parodontal treatment and after implantation treatment.

[Oral ulcerative lesions in young adults]

Following a general discussion of the pathological and clinical aspects of recurring oral ulcerative lesions most frequently observed in dentistry, the paper illustrates a few typical and atypical clinical cases. In conclusion, the authors make a few comments on the differential diagnosis and therapy of these diseases.

[A comparative evaluation of oral and parenteral cephalosporins in inhibiting the growth of bacteria pathogenic to the periodontium]

A study was carried out in vitro to assess the inhibitory activity on the growth of Bacteroides gingivalis and Bacteroides intermedius using two oral cephalosporins (Cephalexin and Cephradine) in comparison to two parenteral cephalosporins (Cefotaxime and Ceftriaxon) and the classic Tetracycline HCl. The results of the study show that the inhibitory activity on the growth of the two periodontopathogenic bacteria produced by the oral cephalosporins is comparable to that of other antibiotics studied, and that in comparison to parenteral cephalosporins the former have the advantage of being better accepted and more economic.

[The in vitro sensitivity of Bacteroides gingivalis and Bacteroides intermedius to different classes of antibiotic chemical molecules]

A study was carried out to assess the in vitro sensitivity of Bacteroides gingivalis and Bacteroides intermedius to various classes of chemio-antibiotic molecules. The activities of two cephalosporins (cefuroxime and cefotaxime), which have never previously been used for periodontal therapy, were also evaluated. Results showed that the cephalosporins possessed an equal or greater inhibitory activity against the bacteria studied than traditional tetracyclines, and a greater inhibitory activity than other antibiotics studied (metronidazole, ampicillin, piperacillin). Further studies are required to assess in vivo efficacy of cephalosporin therapy in severe periodontal diseases.