Transcatheter closure of large patent ductus arteriosus with severe pulmonary arterial hypertension in adults: immediate and two-year follow-up results / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Transcatheter closure of patent ductus arteriosus (PDA) is a well established procedure and an accepted treatment modality for small to moderate-sized PDA. This study aimed to evaluate the immediate and follow-up results of transcatheter closure of large PDAs with severe pulmonary arterial hypertension (PAH) in adults.</p><p><b>METHODS</b>After a complete hemodynamic evaluation differentiating from the reversibility of severe PAH, transcatheter closure of PDA was performed. Patients were followed up clinically and echocardiographically at 24 hours, 1 month, 3 months, 6 months, 12 months and 24 months after occlusion.</p><p><b>RESULTS</b>Twenty-nine patients had successful occlusion, pulmonary artery pressure (PAP), left ventricular ejection fraction (LVEF) and fractional shortening (FS) significantly decreased immediately after occlusion ((106 ± 25) mmHg vs. (50 ± 14) mmHg, P < 0.01; (63.7 ± 7.2)% vs. (51.4 ± 10.1)%, P < 0.01 and (36.9 ± 8.2)% vs. (28.9 ± 8.6)%, P < 0.05, respectively). At 1 month after PDA closure, the signs and symptoms improved markedly in all 29 patients, and PDAs were completely closed and remained closed during the follow-up. Eighteen patients having different degrees of dyspnea were treated with angiotensin converting enzyme inhibitor (ACEI) and/or digoxin after occlusion. Nine patients whose pulmonary vascular resistence (PVR) > 6 Wood units accepted targeted PAH therapy. After 1 to 3 months of peroral drug therapy, their exercise tolerance improved from New York Heart Association (NYHA) class III-IV to NYHA class I. During follow-up, no latent arrhythmias were found, the left atrial diameter (LAD), left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVESD), left ventricular mass index (LVMI) and pulmonary artery systolic pressure (PASP) decreased significantly (P < 0.05), and FS and LVEF recovered compared to the immediate postclosure state. However, FS and LVEF remained low compared to the preclosure state.</p><p><b>CONCLUSIONS</b>Transcatheter closure of large PDA with severe PAH is feasible, effective, and safe in adults. Significant left ventricular systolic changes may occur after closure of large PDA, and left ventricular function usually recovers within a few months.</p>

The surface display of porcine parvovirus VP2 protein in Lactobacillus casei / 生物工程学报

Lactobacillus casei 393 was selected as a bacterial carrier for the expression of Porcine Parvovirus (PPV) protective antigen VP2 protein. The gene encoding PPV VP2 protein was cloned into the Lactobacillus casei surface expression vector pPG, and then the constructed recombinant vector pPG-VP2 was electrotransformed into Lactobacillus casei 393 generating the recombinant system pPG-VP2/L. casei393 expressing PPV VP2 protein. The recombinant strain was induced by 2% Lactose in MRS and about 74kD protein was detected with SDS-PAGE. The result of Western-blot indicated that the expressed protein possessed the antigenic specificity which could be recognized by mouse anti-PPV serum. The indirect immunofluorescent test showed that the expressed protein was secreted on the cell surface Lactobacillus casei.