Severity of Mitral Regurgitation before and after Kidney Transplantation.

BACKGROUND: Perivalvular and valve involvement are prevalent in patients with end-stage renal disease (ESRD), especially in younger patients compared with normal population. Kidney transplantation improves the prognosis of these patients. Patients with cardiac valvular disease is also be improved following kidney transplantation. OBJECTIVE: To evaluate the impact of renal transplantation on the severity of mitral regurgitation (MR). METHODS: We studied 95 kidney transplantation candidates in Sina Hospital. The patients underwent echocardiography preoperatively and at the 3rd, 6th, and 12th months post-operatively. RESULTS: Pre-operatively, the average MR fraction was 30%; MR volume 30 mL/beat; mitral valve mean gradient 1.8 mm Hg; mitral valve area 4.6 cm2; and mitral annular size 3 cm. No significant difference was observed among the measurements made at the 3rd, 6th, and 12th months post-operatively. CONCLUSION: There was no significant association between the variables measured pre- and post-operatively. The reason might be the fact that patients with ESRD in Iran do not have to expect long transplant waiting lists and dialysis cannot affect their heart adversely.

Identification that KfiA, a protein essential for the biosynthesis of the Escherichia coli K5 capsular polysaccharide, is an alpha -UDP-GlcNAc glycosyltransferase. The formation of a membrane-associated K5 biosynthetic complex requires KfiA, KfiB, and KfiC.

The Escherichia coli K5 capsular polysaccharide consists of the repeat structure -4)GlcA-beta(1,4)-GlcNAc-alpha(1- and requires the KfiA, KfiB, KfiC, and KfiD proteins for its synthesis. Previously, the KfiC protein was shown to be a beta-UDP-GlcA glycosyltransferase, and KfiD was shown to be a UDP-Glc dehydrogenase. Here, we demonstrate that KfiA is an alpha-UDP-GlcNAc glycosyltransferase and that biosynthesis of the K5 polysaccharide involves the concerted action of the KfiA and KfiC proteins. By site-directed mutagenesis, we determined that the acidic motif of DDD, which is conserved between the C family of glycosyltransferases, is essential for the enzymatic activity of KfiA. In addition, by Western blot analysis, we determined that association of KfiA with the cytoplasmic membrane requires KfiC but not KfiB, whereas the interaction of KfiC with the cytoplasmic membrane was dependent on both KfiA and KfiB. Likewise, KfiB was only detectable in cytoplasmic membrane fractions when both KfiA and KfiC were present. These data suggest that the interaction between the KfiA, KfiB, and KfiC proteins is essential for the stable association of these proteins with the cytoplasmic membrane and the biosynthesis of the K5 polysaccharide.