Reduced Rate of Neural Differentiation in the Dentate Gyrus of Adult Dysbindin Null (Sandy) Mouse

Genetic variations in the gene encoding dysbindin has consistently been associated with schizophrenia and bipolar disorder, although little is known about the neural functions carried out by dysbindin. To gain some insight into this area, we took advantage of the readily available dysbindin-null mouse sandy (sdy−/−) and studied hippocampal neurogenesis using thymidine analogue bromodeoxuridine (BrdU). No significant differences were found in the proliferation (4 hours) or survival (1, 4 and 8 weeks after the last BrdU injection) of progenitors in the subgranular regions of the dentate gyrus between sdy−/− and sdy+/+ (control) mice. However, 4 weeks after the last BrdU injection, a significant reduction was observed in the ratio of neuronal differentiation in sdy−/− when compared to that of sdy+/+ (sdy+/+  = 87.0±5.3% vs. sdy−/−  = 71.3±8.3%, p = 0.01). These findings suggest that dysbindin plays a role during differentiation process in the adult hippocampal neurogenesis and that its deficit may negatively affect neurogenesis-related functions such as cognition and mood

A histological and clinical comparison of new and conventional integrated backscatter intravascular ultrasound (IB-IVUS)

Background: While the utilization of integrated backscatter intravascular ultrasound (IB-IVUS) for the quantitative in vivo assessment of coronary plaque continues to grow, the validity of IB-IVUS images obtained from newly developed and conventional systems remains uncertain. Methods and Results: To assess the accuracy and reliability of a newly developed IB-IVUS system (VISIWAVE) as compared to the conventional system (Clearview), we compared quantitative IB-IVUS plaque characteristics in the 2 systems using 125 post-mortem specimens from 26 coronary arteries in 11 cadavers, as well as using 200 clinical plaques in 32 patients undergoing coronary intervention. The overall agreement between the histological and IB-IVUS diagnoses using VISIWAVE (Cohen's κ=0.82, 95%CI: 0.73-0.90) was similar to that using Clearview (Cohen's κ=0.80, 95%CI: 0.71-0.89). The 2 systems also demonstrated comparably high sensitivity and specificity. In the direct comparison, the overall agreement between IB-IVUS diagnoses using VISIWAVE and Clearview was also excellent (Cohen's κ=0.87, 95%CI: 0.78-0.95). In the clinical comparison, measured plaque dimensions were similar (VISIWAVE: 8.27±3.46 mm 2 vs. Clearview; 8.31±3.46 mm 2, P=0.44) and there was strong concordance between both greyscale and IB-IVUS parameters. Conclusions: There was close agreement of analyzed results in both systems when compared with the gold standard of histology. Both systems are able to reliably and accurately characterize coronary plaque and thereby make a valuable contribution to our understanding of atherosclerosis

How clinically effective is intravascular ultrasound in interventional cardiology? Present and future perspectives

Intravascular ultrasound (IVUS) has been clinically available for almost 25 years now and showed us valuable information regarding the coronary vessel lumen, its dimensions, the plaque burden and plaque characteristics that we were not able to assess by angiography alone. Using these abilities, IVUS has helped us to start, understand the atherosclerotic process in the coronary vessels. Further technical innovations partially overcame the somewhat limited image resolution of IVUS allowing more in-depth characterization and quantification of coronary plaque components. In addition, IVUS has been shown to be helpful to guide interventional procedures including optimal stent deployment in many clinical situations. In this review, we focus on the potential role of IVUS technology in interventional cardiology and on the valuable role of IVUS usage in percutaneous coronary interventions