The effect of chemical and/or mechanical conditioning on the Er:YAG laser-treated root cementum: analysis of surface morphology and periodontal ligament fibroblast attachment

BACKGROUND AND OBJECTIVES: This study compared the surface morphology as well as the biocompatibility of dental root cementum treated with Er:YAG laser irradiation alone and with the laser irradiation followed by chemical and/or mechanical conditioning. STUDY DESIGN/MATERIALS AND METHODS: Healthy cementum plates were randomly assigned to the following control and treatment groups: (1) untreated control (C), (2) Er:YAG laser irradiation (L), (3) laser plus tetracycline HCl (TC) placement (L+TP), (4) laser plus TC burnishing (L+TB), (5) laser plus EDTA gel placement (L+EP), (6) laser plus EDTA gel burnishing (L+EB), (7) laser plus saline solution burnishing (L+SB), and (8) laser plus minocycline-HCl paste placement (L+MP). Specimens were subjected to scanning electron microscopy (SEM), histological observation and attachment assay using periodontal ligament (PDL) fibroblasts. RESULTS: The laser irradiation produced a thin affected layer (5.7 microm thickness) with a superficial microstructure on the cementum surface. The characteristic microstructures of the lased surface were fragile and could be removed by chemical and/or mechanical conditioning treatments. The L+TB group exhibited marked exposure of collagen fibers after removal of the microstructures on the lased surface. The L+EP group presented a peculiar, smooth surface without exposure of collagen fibers and a uniform arrangement of spherical microparticles on the ultra-high magnification of SEM. In cell attachment assay, the L+TB group exhibited the greatest number of attached cells among all the groups, followed by the L+EP, L+SB and control group. The laser alone group exhibited the lowest number of cells. CONCLUSIONS: The characteristic microstructure of the root cementum surface after Er:YAG laser irradiation has a tendency to hinder the early attachment of PDL cells. However, chemical and/or mechanical root conditioning treatment may improve and increase the biocompatibility of the Er:YAG laser-treated root cementum by removing the microstructures of the surface and/or further exposing the collagen fibers.     

Effects of steroid therapy on membranous nephropathy

BACKGROUND: Although membranous nephropathy is a common cause of nephrotic syndrome in adults, its treatment remains under debate. METHODS: To clarify the effects of steroid therapy, the data of 51 Japanese adult patients with idiopathic membranous nephropathy who received treatment at our department were analyzed retrospectively. We divided the patients with nephrotic syndrome and a serum creatinine level <1.7 mg/dL, into two groups: the steroid therapy group (n=20) and the non-steroid therapy group (n=7), and compared the clinical characteristics between the two groups. RESULTS: Significantly decreased proteinuria levels (p<0.05) after 2 and 5 years were observed in the steroid therapy group as compared to the non-steroid therapy group. There was no significant difference in the serum creatinine levels after 2 and 5 years between the steroid therapy group and the non-steroid therapy group. CONCLUSION: Steroid therapy in idiopathic membranous nephropathy showed good efficacy in patients with nephrotic syndrome.     

Short-term outcome of extracardiac lateral tunnel using the atrial free wall and autologous pericardium

BACKGROUND: Several modifications to the original Fontan procedure have been proposed in order to decrease postoperative morbidity. Lateral tunnel and extracardiac total cavo-pulmonary connection are 2 such modifications. PATIENTS: Between August 2005 and December 2005, the extracardiac lateral tunnel procedure was performed in 5 patients. The age at operation ranged from 19 to 59 months (median 24 months) and the weight ranged from 9.2 to 16.1 kg (median 11.4 kg). RESULTS: There was no mortality. The mean operation time was 466 +/-118 minutes. The mean cardiopulmonary bypass time was 198 +/- 61 minutes. The mean durations of intubation, intensive care unit stay, drainage tube use, and hospital stay were 1 +/- 1, 7 +/- 3, 12 +/- 5 and 30 +/- 2 days, respectively. Postoperative catheterization findings demonstrated that the mean superior venous caval pressure, inferior venous caval pressure, ventricular volume and ventricular ejection fraction were 10.0 +/- 1.4 mmHg, 11.0 +/- 2.4 mmHg, 140 +/- 47% of normal and 58.0 +/- 6.8% , respectively. CONCLUSIONS: The short-term results of the extracardiac lateral tunnel compared favorably with the results of different types of Fontan operation. In addition this procedure has the potential for growth and anticoagulation therapy is unnecessary.     

Arterial switch operation: late results and a future perspective

Intermediate results of the arterial switch operation for variety of cardiac anomaly with the transposed great arteries were studied to elucidate late results and problems. Seventy-five survivors of the arterial switch operation at our institute between 1991 and January 2007 were studied retrospectively. Mean follow-up time was 7.5 years. There were 2 late deaths, 3 reoperations, and 9 cases of catheter intervention, resulting in actuarial survival of 97%, and event-free rate of 83% at 16 years. Seventy patients (93%) were medication free and had no restriction on physical activities. Moderate pulmonary stenosis in 2 patients and mild pulmonary stenosis in 14 were observed. Moderate aortic regurgitation in 2 and mild aortic regurgitation in 20 were observed. Risk factors for right ventricular outflow obstruction were a diagnosis of double outlet right ventricle (DORV), association with aortic arch obstruction, and prior pulmonary artery banding (PAB). Risk factors for branch pulmonary artery stenosis (PS) were not clear; however, scar formation with use of xenograft patch and in-fold formation by redundant autologous pericardial patch for closure of the defects in the old aortic root seemed to be related with the stenosis. Risk factors for aortic regurgitation were age at operation and prior PAB. Early primary arterial switch operation may resolve these problems.     

Protection of visceral organs with an aortic occlusion balloon catheter and by femoral perfusion in aortic arch replacement

A 68-year-old man developed hemoptysis. Prominent left 1st arch was pointed out by chest X-p, and enhanced computed tomography (CT) revealed 60-mm distal arch aneurysm. Protrusion of the aneurysm strongly suggested aorto-pulmonary fistula. The operation was performed via median sternotomy. Cardiopulmonary bypass was established with the ascending aorta cannulation. During systemic cool down, an aortic occlusion balloon (Equalizer) was inserted in the right femoral artery and its position was monitored by transesophageal echography. Femoral perfusion cannula was inserted in the right femoral artery distal to the site of the Equalizer insertion. When the rectal temperature reached 28 degrees C, Equalizer was inflated and femoral perfusion was started. After the aortic arch was incised, balloon-tipped cannula were inserted into the aortic arch vessels. At this point, separate antegrade cerebral perfusion and lower body perfusion were established. The aortic arch was replaced with woven Dacron tube graft. It took 60 minutes to accomplish distal anastomosis, and urination was 80 ml during this period. Postoperative course was uneventful without renal dysfunction. This method of visceral organ protection seemed to be useful for the patients with impaired renal or liver function and for the patients whose distal anastomosis is difficult.