Surgical experience with diseases of the tricuspid valve. Cross-sectional and Doppler echocardiographic evaluation following DeVega's repair

Seventy-eight patients undergoing mitral valve surgery with or without replacement of the aortic valve also underwent procedures on the tricuspid valve over a period of 10 years. All patients were in functional class III or IV preoperatively. The procedures were performed in all patients with organic disease of the tricuspid valve (N = 44) and in those with moderate or severe functional tricuspid valvar regurgitation (N = 34). Seventy-one patients underwent DeVega's annuloplasty with or without commissurotomy. The overall mortality was 11.5%. 65 long-term survivors were followed up for a period of 6 months to 10 years (mean 5.3 years). Sixty-three patients were in functional class I or II at the last follow-up. Six patients had clinical evidence of mild to moderate tricuspid regurgitation. Regression of cardiomegaly (as judged by the chest radiograph and right ventricular hypertrophy seen in the electrocardiogram) was evident in most cases. Fifty-one of 54 patients evaluated by cross-sectional echocardiography were reported to have a functionally normal tricuspid valve. Doppler echocardiography in 28 patients showed no significant tricuspid regurgitation or stenosis in 26 patients. Eleven consecutive patients undergoing DeVega's annuloplasty were studied prospectively with pre- and postoperative Doppler echocardiography. Good correlation existed between right ventricular systolic pressures predicted by Doppler with those obtained preoperatively at cardiac catheterization. Postoperative Doppler echocardiography in these 11 patients showed complete restoration of competence of the tricuspid valve as well as normalisation of the right ventricular systolic pressure in 10 patients.     

Identification of a cellulose synthase-associated protein required for cellulose biosynthesis

Cellulose synthase-interactive protein 1 (CSI1) was identified in a two-hybrid screen for proteins that interact with cellulose synthase (CESA) isoforms involved in primary plant cell wall synthesis. CSI1 encodes a 2,150-amino acid protein that contains 10 predicted Armadillo repeats and a C2 domain. Mutations in CSI1 cause defective cell elongation in hypocotyls and roots and reduce cellulose content. CSI1 is associated with CESA complexes, and csi1 mutants affect the distribution and movement of CESA complexes in the plasma membrane.