Mouse model of dermal fibrosis induced by one-time injection of bleomycin-poly(L-lactic acid) microspheres

Objective. Animal models are useful tools to study various aspectsof human diseases. Bleomycin (BLM)-induced scleroderma mousehas been widely investigated as an animal model of scleroderma.Repeated injections of BLM, either daily or every other day,for 3–4 weeks are required to induce scleroderma in mice.Poly(L-lactic acid) (PLA) is a biodegradable, biocompatibleand bioabsorbable device that has been widely investigated forcontrolled drug release. In this study, we fabricated BLM-containingPLA microspheres and subcutaneously injected them into C3H micefor only one time. Methods. Treated skins were harvested at days 7 and 21. Then,histological examination and collagen content measurement assaywere performed. The mRNA expression of 1(I) collagen (COL1A1),monocyte chemoattractant protein-1 (MCP-1), TGF-β₁ andconnective tissue growth factor (CTGF) were quantified by real-timePCR. Results. Dermal fibrosis was histologically observed at day7 after injection and remained present at day 21. Tissue responsesagainst BLM-PLA microspheres alone were mild. Soluble collagencontent and expression level of 1(I) collagen mRNA were significantlyelevated at day 21. Expression levels of MCP-1 mRNA and TGF-β₁mRNA at day 7 and CTGF mRNA at day 21 were also elevated. Conclusion. The present study demonstrated for the first timethat one-time injection of BLM-PLA microspheres can induce dermalfibrosis in C3H mice. BLM-PLA microspheres thus offer a labour-saving,simple and powerful tool to establish an animal model of BLM-induceddermal fibrosis. KEY WORDS: Bleomycin, Scleroderma, Mouse model, Dermal fibrosis, Drug delivery system, Poly(L-lactic acid) Submitted 11 October 2007; revised version accepted 24 January 2008.     

A Case of Cardiac Amyloidosis Presenting with Mid- to Late Diastolic Retrograde Flow from the Left Atrium to the Pulmonary Vein: Transesophageal Pulsed Doppler Echocardiographic Observations

A patient of cardiac amyloidosis was found to have mid-to late diastolic retrograde flow from the left atrium (LA) to the pulmonary vein. Congo-red staining was positive for amyloid in the rectal tissue. M-mode and two-dimensional echocardiograms revealed symmetric hypertrophy and typical speckled pattern of the left ventricle (LV). The LV pressure curve showed a dip and plateau configuration during diastole, and end-diastolic pressure was 28 mmHg. In addition, the LV pressure was high at mid-diastole, surpassing the pulmonary capillary wedge pressure from mid-to late diastole. The transmitral flow velocity revealed "restrictive" pattern, and the pulmonary venous flow velocity showed retrograde flow from the LA to the pulmonary vein during mid-diastole and atrial systole. It is suggested that recording of the pulmonary venous flow velocity by transesophageal pulsed Doppler echocardiography is useful for understanding the mechanism of the development of pulmonary congestion or edema.     

Enhanced wound healing by topical administration of mesenchymal stem cells transfected with stromal cell-derived factor-1

The objective of this study was to investigate the ability of mesenchymal stem cells (MSC) genetically engineered with stromal cell-derived factor-1 (SDF-1) to heal skin wounds. When transfected with SDF-1 plasmid DNA, MSC which were isolated from the bone marrow of rats, secreted SDF-1 for 7 days. In vitro cell migration assay revealed that the SDF-1-engineered MSC (SDF-MSC) enhanced the migration of MSC and dermal fibroblasts to a significantly greater extent than MSC. The SDF-MSC secreted vascular endothelial growth factor, hepatocyte growth factor, and interleukin 6 at a significantly high level. A skin defect model of rats was prepared and MSC and SDF-MSC were applied to the wound to evaluate wound healing in terms of wound size and histological examinations. The wound size decreased significantly faster with SDF-MSC treatment than with MSC and PBS treatments. The length of the neoepithelium and the number of blood vessels newly formed were significantly larger. A cell-tracing experiment with fluorescently labeled cells demonstrated that the percent survival of SDF-MSC in the tissue treated was significantly high compared with that of MSC. It was concluded that SDF-1 genetic engineering is a promising way to promote the wound healing activity of MSC for a skin defect.     

Terminal stage cardiac findings in patients with cardiac Fabry disease: an electrocardiographic, echocardiographic, and autopsy study

OBJECTIVES: Fabry disease is caused by deficiency of alpha-galactosidase A, and typically causes multi-organ dysfunction. Patients with manifestations limited to the heart, mainly left ventricular hypertrophy (LVH), have been reported as a disease variation. We have reported a 3% prevalence of this cardiac variant in men with LVH, which we designated 'cardiac Fabry disease'. The purposes of this study were to evaluate the terminal stage cardiac manifestations and autopsy findings in patients with cardiac Fabry disease. METHODS: We examined seven terminal stage patients with cardiac Fabry disease. During hospitalization, standard 12-lead electrocardiograms, Holter electrocardiograms, and echocardiograms were obtained. Autopsies were performed and macroscopic along with microscopic findings were evaluated. RESULTS: Six patients died of heart failure and one of ventricular fibrillation. Electrocardiograms revealed the presence of conduction abnormalities and nonsustained ventricular tachycardia. Echocardiograms and autopsy findings revealed LVH in all patients. Localized basal posterior wall thinning of the left ventricle was detected in the six patients who died of heart failure. All patients had severe left ventricular dysfunction. Histologically, myocardial cells, but not cardiac vascular endothelial cells, showed glycosphingolipid accumulation. No accumulation was observed in other organs or in systemic vascular endothelial cells. CONCLUSIONS: Severe left ventricular dysfunction with associated conduction disturbances and ventricular arrhythmias occur in patients with terminal stage cardiac Fabry disease. Furthermore, LVH is present and associated with thinning of the base of the left ventricular posterior wall. In contrast to typical Fabry disease, accumulation of glycosphingolipids was observed in myocardial cells but not in other organs.     

Ulcerative Colitis and Immunoglobulin G4

Background/Aims

Ulcerative colitis (UC) is sometimes associated with autoimmune pancreatitis (AIP). Infiltration of immunoglobulin G4 (IgG4)-positive plasma cells is sometimes detected in the colonic mucosa of AIP or UC patients. This study aimed to clarify the relation between UC and IgG4.

Methods

Associations with UC were reviewed in 85 AIP patients. IgG4 immunostaining was performed on biopsy specimens from the colonic mucosa of 14 AIP and 32 UC patients.

Results

UC was confirmed in two cases (type 1 AIP, n=1; suspected type 2 AIP, n=1). Abundant infiltration of IgG4-positive plasma cells in the colonic mucosa was detected in the case of suspected type 2 AIP with UC and two cases of type 1 AIP without colitis. Abundant infiltration of IgG4-positive plasma cells was detected in 10 UC cases (IgG4-present, 31%). Although 72% of IgG4-absent UC patients showed mild disease activity, 70% of IgG4-present patients showed moderate to severe disease activity (p<0.05).

Conclusions

UC is sometimes associated with AIP, but it seems that UC is not a manifestation of IgG4-related disease. Infiltration of IgG4-positive plasma cells is sometimes detectable in the colonic mucosa of UC patients and is associated with disease activity.     

Chronic kidney disease status modifies the association of CYP2C19 polymorphism in predicting clinical outcomes following coronary stent implantation

Introduction

There is some controversy regarding the effect of CYP2C19 polymorphism on clinical outcome in patients with dual antiplatelet therapy. Chronic kidney disease (CKD) is associated with increased risk of cardiovascular event, but the association between the possession of CYP2C19 loss-of-function (LOF) alleles and clinical outcome according to the presence of CKD is poorly understood. The aim of this study was to investigate whether CKD status modifies the association of CYP2C19 polymorphism in predicting outcomes in a prospective cohort study.

Material and Methods

We enrolled 331 patients following coronary stent implantation. Patients were divided into two groups: CKD (n = 154) and non-CKD (n = 177). Platelet reactivity and CYP2C19 polymorphism were examined. The subjects were further divided into two groups according to the possession of CYP2C19 LOF alleles: carriers and non-carriers. Patients were followed up and clinical events were evaluated according to CKD and carrier status.

Results

The proportion of high platelet reactivity was significantly higher in carriers than in non-carriers in both CKD (42.4% versus 21.7%; P = 0.016) and non-CKD groups (34.3% versus 3.7%; P < 0.001). In the non-CKD group alone, the incidence of cardiovascular events was significantly higher in carriers than in non-carriers (13.7% versus 1.7%; P = 0.013). Kaplan-Meier analysis demonstrated a significantly higher probability of cardiovascular events in carriers than in non-carriers in the non-CKD group (log-rank test: P = 0.013) and there was no significant difference in the CKD group (log-rank test: P = 0.591). Multivariate analysis identified carriers as an independent predictor of cardiovascular events only in the non-CKD group alone (hazard ratio: 8.048; 95% confidence interval: 1.066 to 60.757; P = 0.043).

Conclusions

CYP2C19 polymorphism significantly correlates with clinical outcome in non-CKD patients, and CKD status modifies the association of CYP2C19 polymorphism in predicting clinical outcomes following coronary stent implantation.     

Usefulness of pet ownership as a modulator of cardiac autonomic imbalance in patients with diabetes mellitus, hypertension, and/or hyperlipidemia

Among patients with coronary artery disease, pet owners exhibit a greater 1-year survival rate than nonowners. Lifestyle-related diseases are well-known risk factors for coronary artery disease and induce imbalances in autonomic nervous activity. The purpose of the present study was to determine whether pet ownership modulates cardiac autonomic nervous activity imbalance in patients with lifestyle-related diseases such as diabetes mellitus, hypertension, and hyperlipidemia. A total of 191 patients (mean age 69 ± 8 years) were interviewed about their pet ownership status and were classified into pet owner and nonowner groups. After recording a 24-hour Holter electrocardiogram for heart rate variability analysis, frequency-domain and nonlinear-domain analyses were performed to determine the high-frequency (HF) and low-frequency (LF) components, LF/HF ratio, and entropy. The heart rate variability parameters were assessed for 24 hours, during the day (8.00 A.M. to 5.00 P.M.), and during the night (0:00 A.M. to 6.00 A.M.), and compared between the 2 groups. To evaluate the potential predictive factors for cardiac autonomic imbalance, univariate and multivariate analyses of HF and LF/HF were conducted for potential confounding variables. The pet owner group exhibited significantly greater HF(24h), HF(day), HF(night), entropy(24h), entropy(day), and entropy(night) and significantly lower LF/HF(24h) and LF/HF(night) compared to the nonowner group. On multivariate analysis, pet ownership was independently and positively associated with HF(24h,) HF(day), and HF(night) and inversely associated with LF/HF(24h) and LF/HF(night). In conclusion, these results suggest that pet ownership is an independent modulator of cardiac autonomic imbalance in patients with lifestyle-related diseases.