Congenitally corrected transposition and mitral atresia complicated by restrictive atrial septum

Congenitally corrected transposition (ccTGA), also known as L-transposition of the great arteries (L-TGA), is a rare cardiac malformation accounting for approximately 0.05% of congenital heart disease, characterized by ventricular inversion, discordant ventriculo-arterial connections with a normal visceroatrial relationship. It was first described by Baron Rokitansky in 1875, and prenatal sonographic diagnosis can be difficult. Symptomatology and clinical presentation of this malformation are related to the associated intracardiac defects. We report a rare case of severe, complex cardiac disease: prenatally diagnosed ccTGA with atrial restriction, mitral atresia, Ebsteinoid tricuspid valve, and severe pulmonary valve stenosis, who subsequently developed left pulmonary vein stenosis.     

Mapping the calcification of bovine pericardium in rat model by enhanced micro-computed tomography

The calcification initiation and progression of bioprosthetic heart valve were investigated in a rat model by enhanced micro-computed tomography, together with histologic study and scanning electron microscope analysis. The implantation data at early stage showed apparent dendritic patterns in the radiographic images for the glutaraldehyde-treated bovine pericardium and this dendritic pattern was verified to be associated with the vessel distribution in the tissue. Histologic study and scanning electron microscope analysis both indicated that the calcium deposits in the pericardium vessels regions were more grievous than those scattered in the collagen fibers in the first two weeks after implantation. Subsequently, calcification spreaded and the entire sample was severely calcified in 60 days.     

Myocardial contraction and hyaluronic acid mechanotransduction in epithelial-to-mesenchymal transformation of endocardial cells

Epithelial-to-mesenchymal transition (EMT) of endocardial cells is a critical initial step in the formation of heart valves. The collagen gel in vitro model has provided significant information on the role of growth factors regulating EMT but has not permitted investigation of mechanical factors. Therefore we sought to develop a system to probe the effects of mechanical inputs on endocardial EMT by incorporating hyaluronic acid (HA), the primary component of endocardial cushions in developing heart valves, into the gel assay. This was achieved using a combination collagen and crosslinkable methacrylated HA hydrogel (Coll-MeHA). Avian atrioventricular canal explants on Coll-MeHA gels showed increased numbers of transformed cells. Analysis of the mechanical properties of Coll-MeHA gels shows that stiffness does not directly affect EMT. Hydrogel deformation from the beating myocardium of explants directly led to higher levels of regional gel deformation and larger average strain magnitudes associated with invaded cells on Coll-MeHA gels. Inhibition of this contraction reduced EMT on all gel types, although to a lesser extent on Coll-MeHA gels. Using the system we have developed, which permits the manipulation of mechanical factors, we have demonstrated that active mechanical forces play a role in the regulation of endocardial EMT.     

Tri-layered elastomeric scaffolds for engineering heart valve leaflets

Tissue engineered heart valves (TEHVs) that can grow and remodel have the potential to serve as permanent replacements of the current non-viable prosthetic valves particularly for pediatric patients. A major challenge in designing functional TEHVs is to mimic both structural and anisotropic mechanical characteristics of the native valve leaflets. To establish a more biomimetic model of TEHV, we fabricated tri-layered scaffolds by combining electrospinning and microfabrication techniques. These constructs were fabricated by assembling microfabricated poly(glycerol sebacate) (PGS) and fibrous PGS/poly(caprolactone) (PCL) electrospun sheets to develop elastic scaffolds with tunable anisotropic mechanical properties similar to the mechanical characteristics of the native heart valves. The engineered scaffolds supported the growth of valvular interstitial cells (VICs) and mesenchymal stem cells (MSCs) within the 3D structure and promoted the deposition of heart valve extracellular matrix (ECM). MSCs were also organized and aligned along the anisotropic axes of the engineered tri-layered scaffolds. In addition, the fabricated constructs opened and closed properly in an ex vivo model of porcine heart valve leaflet tissue replacement. The engineered tri-layered scaffolds have the potential for successful translation towards TEHV replacements.     

Anterior urethral valves without diverticulae: A report of two cases and a review of the literature

Two unusual cases of anterior urethral valves (AUV) without diverticulae are presented. The first case is a male child born with prenatal diagnosis of bilateral hydronephrosis. On cystoscopy, iris‐like diaphragm valves were encountered about 3 mm distal to the skeletal sphincter. In the second case, an 18‐month‐old male child was investigated for recurrent febrile urinary tract infections and obstructed urinary symptoms. Cystoscopy confirmed the presence of slit‐like valves 5 mm distal to the skeletal sphincter. Fulguration of the AUVs was performed in both cases. It may be worthwhile to review all cases of anterior urethral obstruction collectively and re‐categorize them appropriately to include the unusual AUVs without diverticulum in that classification.     

唇腭裂患者口腔修复治疗的临床体会

目的：讨论固定桥修复、活动义齿修复、双重牙列修复这三种保守修复方法在唇腭裂患者口腔修复中的初步临床体会。方法：结合100例唇腭裂患者保守修复的治疗经验,讨论三种保守治疗方法的临床适应症和优缺点。结果：唇腭裂患者的保守修复治疗方法可以一定程度上恢复咀嚼功能和颌面外观,修复口鼻瘘,改善发音,同时获得心理康复等。结论：对于不能手术治疗的患者,在选择好适应症后,保守性修复治疗是一种简单、经济、实用的修复方法。