Age-related changes in axial and sagittal orientation of the facet joints: Comparison with changes in degenerative spondylolisthesis

Background

Despite facet joints being three-dimensional structures, previous computed tomography and magnetic resonance imaging studies have evaluated facet joint orientation in only the axial plane. Facet joint orientation in the sagittal plane has rarely been studied using these imaging techniques. The aim of this study was to elucidate facet joint orientation in both the axial and sagittal planes on computed tomography.

Efficacy of the circulatory management of an antenatally diagnosed congenital diaphragmatic hernia: outcomes of the proposed strategy

Object

The purpose of this study is to evaluate the outcome of our therapeutic strategy for antenatally diagnosed congenital diaphragmatic hernia (ADCDH).

Methods

We treated 61 cases of ADCDH according to our strategy. Prostaglandin E1 was required to be maintained the patency of the ductus arteriosus (PDA) in 39 cases (Group I) while it was not administered in 22 cases (Group II). Left ventricular end-diastolic dimension (LVDD) and Tei index were measured with echocardiography on days 0, 2, and 7 after birth. Radical surgery was performed on all cases by day 2.

Results

On day 0, Group I showed smaller LVDD and Tei index than those in Group II. Between day 0 and day 2, these parameters increased significantly in Group I, but not in Group II. On day 7, no significant difference in these parameters was observed between the two groups. Five patients died of cardiac and respiratory failure, resulting in a survival rate of 92 %.

Conclusion

Our therapeutic strategy improves the clinical outcome of ADCDH. This can be attributed to two factors: earlier surgery resulting in improved LV function. The latter attenuates pulmonary hypertension and maintains PDA with a consequent decrease in right ventricular afterload to compensate for the low cardiac output resulting from PDA.     

Binding specificity of Fusobacterium nucleatum to human erythrocytes, polymorphonuclear leukocytes, fibroblasts, and HeLa cells

Eighteen strains of Fusobacterium nucleatum were studied with respect to their adherence to human erythrocytes, polymorphonuclear leukocytes, fibroblasts, and HeLa cells. Four types of adherence were found: 1) sugar-sensitive adherence 2) amino acid-sensitive adherence 3) unknown adherence 4) weak adherence. There was no obvious correlation between the patterns of hemagglutination and adherence to other cells. The results indicate not only a complex network of bacterial receptors on human cells, but also a variety of types of bacterial adherence as expressed by the selectivity of the bacterial binding to specific cell surfaces.     

Nicotine inhibits mineralization of human dental pulp cells

Nicotine is a major component of tobacco smoke, and signals via nicotinic acetylcholine receptors (nAChR). However, little is known about the effects of nicotine on human dental pulp cells (HDPCs). In this study, we assessed the effects of nicotine on mineralization in HDPCs. We confirmed messenger RNA expression of nAChR subunits and examined the effects of nicotine on expression of extracellular matrices (ECMs), alkaline phosphatase (ALP) activity, and mineralized nodule formation by HDPCs. Gene expression of nAChR subunits alpha1, alpha2, alpha 4, alpha 5, alpha 6, alpha 7, beta1, beta2, and beta 4 was detected in HDPCs. Interestingly, the messenger RNA expression of dentin matrix acidic phosphoprotein-1, bone sialoprotein, and ALP activity were significantly reduced in nicotine-treated HDPC. In addition, mineralized nodule formation, which was examined by alizarin red staining, was also inhibited in HDPCs by the same treatment. These results indicate that nicotine suppresses the cytodifferentiation and mineralization of HDPCs, possibly via nAChR.     

Microvascular response in the periosteum following mucoperiosteal flap surgery in dogs: angiogenesis and bone resorption and formation

BACKGROUND: When surgical stress reaches the periosteum, bone resorption and formation that occur as a periosteal response are closely related to angiogenesis and hemodynamics. Thus, we investigated bone remodeling in the healing process after mucoperiosteal flap surgery, focusing our attention on the microcirculation. METHODS: Mucoperiosteal flap surgery was performed on 12 adult beagle dogs. The periosteal vascular plexus was observed on days 7, 14, 21, and 28 after surgery, using three different techniques: in histological specimens into which India ink was injected into blood vessels, under a light microscope; in ultrathin sections, using a transmission electron microscope; and in acryl plastic-injected vascular corrosion cast specimens, under a scanning electron microscope. RESULTS: On day 7 after surgery, the interstitum of the elevated mucoperiosteal vascular plexus was filled with sinusoidal new blood vessels. Bone resorption by osteoclasts was observed around these new blood vessels and many highly permeable fenestrations were present in the vascular endothelium. On day 14 after surgery, sinusoidal new blood vessels were more markedly developed and some regions exhibited glomeruluslike morphology consistent with bone resorption cavities. Activated osteoblasts were present around these new blood vessels and highly permeable vesicles, which were considered to be possible vesiclo-vacuolar organelles (VVOs) and caveolae, were noted in the vascular endothelium. On days 21 and 28 after surgery, the mucoperiosteal vascular plexus was dissected through regression of endothelial cells and fibroblasts and reconstructed into a rough mesh structure, and simultaneously the bone surface became smooth. CONCLUSION: The morphology of the mucoperiosteal vascular plexus changed with bone metabolism and these changes contributed to transport of substances involved in periodontal repair.