Effect of low-level laser irradiation on osteoblast proliferation and bone formation.

Applications of laser therapy in biostimulation and healing injured tissues are widely described in medical literature. The present study focuses on the effects of laser irradiation on the growth rate and differentiation of human osteoblast-like cells seeded on titanium or zirconia surfaces. Cells were laser irradiated with low therapeutical doses at different intervals and the effects of irradiation were evaluated at each time-point. After 3 hours lasered cells showed an enhanced mitogen activity compared to non-lasered control cells and a higher alkaline phosphatase activity, marker of bone formation. At the same time, the mRNA of RUNX2 and OSTERIX, two genes involved in osteoblast differentiation, showed a clear decrease in lasered cells. This reached the lowest value 6 to 12 hours after irradiation, after which the transcripts started to increase, indicating that the laser treatment did promote the osteogenic potential of growth-induced cells. These results indicate that Low Level Laser Treatment (LLLT) stimulates osteogenic cell proliferation.

Changes in matrix extracellular phosphoglycoprotein expression before and during in vitro osteogenic differentiation of human dental papilla mesenchymal cells.

The purpose of this study is to characterise the expression of matrix extracellular phosphoglycoprotein (MEPE) in cultured mesenchymal cells isolated from human dental papilla (PaMCs) of impacted third molars either before or during differentiation of these cells into osteo/odontoblasts. PaMCs, like mesenchymal cells deriving from human dental pulp (DPMCs), resulted positive for a number of mesenchymal markers including CD146 and STRO-1. During the first week in culture they showed a faster proliferation rate than DPMCs, coupled to an earlier down-regulation of MEPE. Also when the cells were further cultured in osteogenic medium (containing beta-glycerophosphate, ascorbic acid and dexamethasone) for 40 days, MEPE down-regulation coupled to an increased expression of osteogenic markers, such as osteocalcin and alkaline phosphatase, occurred earlier in PaMCs than in DPMCs. Thus, our data, indicating that also in PaMCs MEPE expression is higher when cells proliferate, whereas it is downregulated as cells differentiated, are in favour of a role of MEPE as an early regulator of odontogenic differentiation. We also confirm the superior proliferative potential of PaMCs in comparison with DPMCs, coupled to a more rapid induction of osteogenic differentiation. Therefore, these cells represent an optimal source to be conveniently used for dental tissue engineering and tooth regeneration.

[Carotid atherosclerosis in patients with suspected coronaropathy: the relationship to traditional risk factors in the 2 vascular areas]. / Aterosclerosi carotidea in pazienti con sospetta coronaropatia: relazione con i fattori di rischio tradizionali nei due distretti vascolari.

UNLABELLED: In order to evaluate the prevalence of carotid atherosclerosis (CA) in patients with coronary artery disease (CAD) and to identify the differential role of traditional risk factors, we analyzed data concerning 290 patients aged 61.9 +/- 10.8 years who underwent color duplex ultrasound of extracranial arteries before coronary angiography. Significant CA (stenosis > or = 50% in at least one extracranial artery) was disclosed in 44 patients (15%); significant CAD (stenosis > or = 70% at least in a major epicardial vessel) was documented in 238 patients (82%). Age and smoking were significantly associated with both CAD (respectively, p = 0.034 and p = 0.050) and CA (respectively, p = 0.000 and p = 0.000), but a stronger correlation was documented with CA (r = 0.325 vs r = 0.125 for age; r = 0.218 vs r = 0.114 for smoking). Diabetes (p = 0.031) and male gender (p = 0.016) were significantly associated with CAD, and hypertension (p = 0.029) with CA. CONCLUSIONS: Traditional risk factors play different roles in the pathogenesis of atherosclerotic disease of carotid and coronary circulation. Color duplex evaluation of the carotid arteries can be useful in high-risk patients, particularly if candidates for coronary surgery.

[Ventricular remodeling after myocardial revascularization with venous grafts]. / Rimodellamento ventricolare dopo intervento di rivascolarizzazione miocardica con condotti venosi.

Left ventricular remodeling, through long-term left ventricular chamber dilation and increased wall stress can result in alteration of ventricular architecture and impairment of systolic and diastolic performance. Most of the studies regard post acute myocardial infarction remodeling, knowledge is still lacking about preoperative and postoperative factors which predict the long-term prognosis of patients who underwent venous coronary artery bypass graft surgery. We evaluated 243 patients (225 males, 18 females, mean age 65 +/- 7.3 years) submitted to venous coronary artery bypass graft surgery and 10-year follow-up (123 +/- 20 months). Global mortality was 17.6% (n = 43), significantly higher in patients with ejection fraction (EF) < 50% (log-rank test p < 0.001). The survivors (n = 200) were subdivided into two groups according to postoperative EF: patients with EF > or = 50% (n = 160) and patients with EF < 50% (n = 40). Multivariate analysis revealed that cardiovascular risk factors (hypertension, diabetes, hypercholesterolemia, smoking), number of grafts and infarct location were not associated with EF reduction. Only multivessel disease was significantly associated with EF reduction (p = 0.008). Preoperative echocardiographic parameter analysis evidenced that regional ventricular wall motion score was significantly higher in patients with reduced EF (EF < 50% 11 +/- 7.5; EF > or = 50% 6 +/- 4.1, p < 0.001) and left ventricular dilation (p < 0.001). Multivariate analysis revealed that the strongest correlates of EF < 50% were left ventricular wall motion score index > 10 (odds ratio 5.8, 95% confidence interval 2.8-11.7) and multivessel disease (odds ratio 9.0, 95% confidence interval 2.6-31.08). This study revealed that echocardiographic detection of preoperative ventricular wall motion score may be useful to assess patients at high risk of ventricular remodeling after venous coronary artery bypass graft surgery.