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Biomedical subjects

Ron M Du Bois

Publications and source records attributed to Ron M Du Bois.

2 recordsLinked to original sources

Endothelin axis polymorphisms in patients with scleroderma.

OBJECTIVE: To evaluate the distribution of polymorphisms in the endothelin 1 (EDN1), endothelin receptor A (EDNRA) and endothelin receptor B (EDNRB) genes in systemic sclerosis (SSc; scleroderma) and SSc subsets. METHODS: Two hundred five patients with SSc and 255 healthy controls were screened for polymorphisms in EDN1, EDNRA, and EDNRB, using sequence-specific primer-polymerase chain reaction. The polymorphisms studied were at the following positions: for EDN1, -1370 (T-1370G) of the promoter, +138 of exon 1 (+138 A/-), +85 of exon 3 (E106E), and +23 of exon 5 (K198N); for EDNRA, -231 of exon 1 (G-231A), and +69(H323H) and +105 (E335E) of exon 6; for EDNRB, +2841 of exon 2 (EDNRB-3), -2547 of exon 3 (EDNRB-2), and -2446 of exon 3 (EDNRB-1). RESULTS: No significant differences between the SSc group as a whole and control subjects were observed for any of the investigated polymorphisms in EDN1, EDNRA, and EDNRB. However, compared with patients with limited cutaneous SSc, patients with diffuse skin involvement had an increased frequency of allele carriage of EDNRB-1A (76.8% versus 54.4%; P = 0.002), EDNRB-2A (79.7% versus 60.2%; P = 0.006), and EDNRB-3G (79.7% versus 56.6%; P = 0.001). Significantly increased carriage frequencies for EDNRA alleles H323H/C and E335E/A were observed in SSc patients with anti-RNA polymerase (anti-RNAP) antibodies, compared with both anti-RNAP-negative SSc patients (P < 0.05) and control subjects (P < 0.005). CONCLUSION: The finding of associations between endothelin receptors A and B and distinct clinical and immunologic SSc subsets supports the role of endothelin and its receptors in the pathogenesis of SSc. However, these findings and their functional significance need to be confirmed and investigated in future studies.

Endothelins↗

Pulmonary capillaritis and its relationship to development of emphysema in hypocomplementaemic urticarial vasculitis syndrome.

Hypocomplementaemic urticarial vasculitis syndrome (HUVS) is a rare disorder characterised by complement activation and the presence of C1q precipitins together with a syndrome of urticarial vasculitis, angioedema, arthralgia, ocular inflammation, glomerulonephritis and obstructive lung disease. The pathophysiology of the obstructive airways disease is poorly understood. We report a 46 year-old woman with HUVS who developed progressive obstructive airways disease. Lung biopsy early in the course of her disease revealed pulmonary capillaritis. The disease progressed despite treatment with steroids and cyclosporin and the patient eventually underwent successful double lung transplantation. The explanted lung showed the coexistence of a patchy active vasculitis with severe panacinar emphysema. This is the first description of the histopathological process of HUVS in an explanted lung. Through analysis of serial histopathological specimens and clinical data we show the evolution of pulmonary capillaritis to emphysema, and demonstrate that active vasculitis can coexist with emphysema in patients with HUVS and obstructive airways disease. We suggest that there is a role for ongoing immunosuppressive therapy in these patients.

Biopsy↗