Simvastatin attenuates the endothelial pro-thrombotic shift in saphenous vein grafts induced by Advanced glycation endproducts

Background

Advanced glycation endproducts (AGEs) and its receptors (RAGEs) are heterogeneous signaling proteins associated to diabetes and responsible of endothelial alterations leading to atherosclerosis progression and graft failure. The aim of this study was to investigate the role of statin in reducing AGEs related endothelial damage.

Methods

Endothelial cell(EC) obtained from leftovers of saphenous vein grafts of non-diabetic patients were incubated with AGEs (2 and 20 μM) and subsequently treated with Simvastatin. Neutrophils (PNM) adherence, ROS production and RAGE and peroxisome proliferator-activated receptors-gamma (PPAR-γ) expression were analyzed. As clinical validation of the in vitro findings, ECs of diabetic patients in optimized glycaemic control administered with a 3 weeks Simvastatin regimen were similarly processed.

Results

Simvastatin blunted the rise in PMN adhesion and ROS generation following stimulation of saphenous vein EC culture with AGEs in vitro. This effect was time dependent and was associated to an increase in PPAR-γ induction paralleled by a decrease in RAGEs expression. Parallely, data from diabetic patients administered with Simvastatin showed a similar significant reduction in PNM adhesion and ROS generation. Simvastatin treatment significantly decreased RAGEs expression in ECs from diabetic patients and determined a slight increase in PPAR-γ expression but the latter failed to reach statistical significance. Interference in the function of these two crucial pathways might be at the root of the statin antinflammatory and antithrombotic effect in the context of AGEs-associated damage.

Conclusions

Despite the recently raised warning on the use of statins in the diabetic population, this study elucidates their cornerstone position in endothelial homeostasis of saphenous grafts in patients with controlled diabetes.     

Action potential propagation in transverse-axial tubular system is impaired in heart failure

The plasma membrane of cardiac myocytes presents complex invaginations known as the transverse-axial tubular system (TATS). Despite TATS's crucial role in excitation-contraction coupling and morphological alterations found in pathological settings, TATS's electrical activity has never been directly investigated in remodeled tubular networks. Here we develop an ultrafast random access multiphoton microscope that, in combination with a customly synthesized voltage-sensitive dye, is used to simultaneously measure action potentials (APs) at multiple sites within the sarcolemma with submillisecond temporal and submicrometer spatial resolution in real time. We find that the tight electrical coupling between different sarcolemmal domains is guaranteed only within an intact tubular system. In fact, acute detachment by osmotic shock of most tubules from the surface sarcolemma prevents AP propagation not only in the disconnected tubules, but also in some of the tubules that remain connected with the surface. This indicates that a structural disorganization of the tubular system worsens the electrical coupling between the TATS and the surface. The pathological implications of this finding are investigated in failing hearts. We find that AP propagation into the pathologically remodeled TATS frequently fails and may be followed by local spontaneous electrical activity. Our findings provide insight on the relationship between abnormal TATS and asynchronous calcium release, a major determinant of cardiac contractile dysfunction and arrhythmias.     

Hood Colonoscopy in Trainees: A Useful Adjunct to Improve the Performance

Background

The use of a transparent hood to improve colonoscopic performance has recently been proposed.

Aims

The purpose of this study was to evaluate whether using the hood might improve the cecal intubation rate, cecal intubation time, number of attempts needed to intubate the ileo-cecal valve, and polyp detection rate in trainees.

Methods

Patients undergoing colonoscopy (n = 378) were randomized in two groups, one studied with hood colonoscopy (n = 179) and the other (n = 199) with standard examination.

Results

No differences were found between hood and standard colonoscopy with respect to cecal intubation rate (95 vs 92 %), whereas hood colonoscopy significantly shortened the cecal intubation time, the number of attempts needed to intubate the ileo-cecal valve, and the overall polyp detection rate (p < 0.01 for all these variables).

Conclusions

Hood colonoscopy might represent a useful adjunct to standard colonoscopy, especially improving the performance of endoscopic trainees.     

Treatment of an upper impacted cuspid using ultrasonic surgery and a modified RPE. A case report

This case report describes the possibility to use a modified rapid palatal expander like anchorage to reposition an included maxillary cuspid. Moreover it is enphasized the use of an ultrasonic device during surgery to expose the impacted tooth.     

Primary extranodal non-Hodgkin's lymphoma of the vagina: a case report and a review of the literature

Primary lymphoma of the female genital tract is very rare. We report the case of a 36-year-old woman who was referred to our hospital because of an indeterminate Pap smear test. The colposcopy showed a thickening of the posterior vaginal wall and various irregular ulcerated nodular lesions. Histological examination, immunohistochemistry and the staging procedures were conclusive of diffuse large B-cell lymphoma of the vagina, stage IEA. Complete remission was achieved after 6 cycles of immunopolychemotherapy (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone). No relapse has occurred during a follow-up of 71 months. Moreover, we reviewed the 62 previously reported cases of primary extranodal non-Hodgkin's lymphoma of the vagina, focusing on clinicopathological and therapeutic aspects, to better characterize this unusual disease.