Ultra-high-speed videography of resin–dentin interface failure dynamics under tensile load

ObjectivesUltra-high-speed (UHS) videography was used to visualize the fracture phenomena at the resin–dentin interface during micro-tensile bond strength (μTBS) test. We also investigated whether UHS videography is applicable for failure-mode analysis.MethodsTen human mid-coronal dentin surfaces were bonded using Clearfil SE Bond either in self-etching (SE) or etch-and-rinse (ER) mode. After 24-h water storage, the samples were cut into beams for μTBS test and tested at a cross-head speed of 1 mm/min. The fracture phenomena at the bonded interface were captured using a complementary metal–oxide–semiconductor digital UHS camera at 299,166 frames per second. The failure modes were classified using UHS videography, followed by scanning electron microscopy (SEM) analysis. The failure-mode distributions determined by UHS videography and SEM analysis were statistically analyzed using Fisher’s exact test with Bonferroni correction.ResultsThe crack-propagation speed exceeded 1,500 km/h. No significant difference was found between the SEM and UHS videography failure-mode distributions in the SE mode. A significant difference appeared between them in the ER mode. Significant differences in the incidence of cohesive failures within the adhesive and at the adhesive–composite interface between the SE and ER modes were identified by both SEM and UHS videography.SignificanceUHS videography enabled visualization of the fracture dynamics at the resin– dentin interfaces under tensile load. However, the resolution at such high frame rate was insufficient to classify the failure mode as precisely as that of SEM. Nevertheless, UHS videography can provide more detailed information about the fracture origin and propagation.     

Role of consultation–liaison psychiatry toward shortening of length of stay for medically ill patients with depression

Depression in physically ill patients is often encountered in consultation– liaison psychiatry. First, this investigation examined the relationship between length of stay (LOS) and depression comorbidity. Physically ill patients with depression stayed significantly longer than those without. Second, the change of LOS with and without antidepressant treatment for depression in medically ill patients has been investigated, which showed that LOS in physically ill patients with depression could be shortened by effective antidepressant treatment. This study also revealed that the early detection and antidepressant treatment are important for physically ill patients with depression that could lead to the shortening of LOS.     

Characterization of CYP2C Induction in Cryopreserved Human Hepatocytes and Its Application in the Prediction of the Clinical Consequences of the Induction

CYP2C enzymes play key roles in drug metabolism, and clinical drug-drug interactions caused by CYP2C induction have been reported. The aim of this study was to establish a method to predict the potency of CYP2C inductions considering the mechanism. We first investigated the relations of CYP2C induction with CYP3A4 or CYP2B6 induction in human hepatocytes after 48-h exposure with 19 inducers. The fold-induction values of CYP2C8 and CYP2C9 were well correlated with those of CYP3A4, whereas the inducers were separated into 2 groups showing different correlations with CYP2B6 induction for CYP2C8 and CYP2C9 induction. In the regression models established, the fold-induction values of CYP2C8 and CYP2C9 were well expressed as the functions of those of CYP3A4 and CYP2B6, while no such obvious correlation was observed for CYP2C19 induction. These results suggest that CYP2Cs are not simply coinduced with CYP3A4 and that CYP2C8 and CYP2C9 inductions are regulated by both pregnane X receptor and constitutive androstane receptor with different contributions. Finally, simple correlations were proposed using the experimental E_max values obtained and plasma concentrations of CYP2C9 substrates from the literature, and positive correlations were observed. These data provide methods to estimate the clinical impact of CYP2C9 induction from in vitro data.     

Surgical management of a primary external iliac venous aneurysm causing pulmonary thromboembolism: report of a case

Primary iliac venous aneurysm is an extremely rare clinical entity. We report a case of primary external iliac venous aneurysm containing an intraluminal thrombus that caused pulmonary thromboembolism in a 22-year-old woman. The aneurysm and pulmonary emboli were detected during examination for sudden onset of dyspnea. After receiving anticoagulation and thrombolytic therapy, the patient underwent aneurysm resection. We devised venoplasty using a dual-row saphenous vein patch to cover the large defect of the vessel wall. Primary iliac venous aneurysms associated with pulmonary thromboembolism are uncommon and surgical repair is made difficult by the fragility of the affected vessel. We reviewed the clinical features of this unusual entity.