Clinical experience in the use of marginal donor hearts / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Although heart transplantation has become a standard therapy for end-stage heart disease, there are few published studies regarding the use of transplant organs from marginal donors. Here we describe the clinical outcome we have obtained using marginal donor hearts.</p><p><b>METHODS</b>We analyzed 21 cases of orthotopic heart transplantation for end-stage heart disease performed in our department between September 2008 and July 2010. Of these patients, six received hearts from marginal donors and the remainder received standard-donor hearts. The two groups were compared in terms of both mortality and the incidence of perioperative complications such as infection, acute rejection, and right heart insufficiency.</p><p><b>RESULTS</b>The 1-year survival rate of both groups was 100%. Only one death was recorded in standard-donor group during follow-up. Patients who received marginal donor hearts (83%) experienced more early complications than did the standard-donor-heart group (13%), but the mortality of the two groups was the same. The duration of post-ICU stay was greater in the marginal donor group than in the standard-donor group, (35.5 ± 17.4) days and (21.7 ± 2.6) days, respectively (P < 0.05).</p><p><b>CONCLUSIONS</b>The use of marginal donor hearts increases the number of patients who can receive and benefit from transplants. However, it may introduce an increased risk of early complications, thus care should be taken both in the choice of patients who will receive marginal donor hearts and in the perioperative treatment of those for whom the procedure is performed.</p>

Atelocollagen-mediated small interfering RNA delivery for effective gene silencing in rat vein grafts / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the efficacy of using small interfering RNA targeting TF as a therapy for vein graft failure.</p><p><b>METHODS</b>External jugular vein to carotid artery interposition vein grafts, which were applied to a low flow condition, were made in 120 Sprague-Dawley rats weighing 260 to 300 g. These rats were randomly divided into 4 groups, 30 rats each group. Group A was atelocollagen-TF Stealth Select RNAi group. Group B was atelocollagen-TF Stealth RNAi group. Group C was atelocollagen group. Group D was control group. Small interfering RNA mixed with atelocollagen was administrated to the external wall of grafted veins. The TF protein expression of vein grafts was analyzed by Western blot at 1, 3, 7, 14, and 28 d postoperatively, and by immunochemistry at 3 d postoperatively. The proliferation index was determined at 14 d postoperatively. Neointimal hyperplasia was evaluated at 28 d postoperatively. BLOCK-iT fluorescent oligo was used to confirm its stability and successful transfer into the vein graft wall at 3 and 7 d postoperatively for another group (n=12).</p><p><b>RESULTS</b>Fluorescence of BLOCK-iT fluorescent oligo could be detected in the graft wall even at 7 d postoperatively. Knockdown of the TF expression was achieved by perivascular application of siRNA using atelocollagen. Compared with control group, the intima thickness at 28 d after grafting was significantly reduced (P < 0.05). This phenomenon was preceded by significant reduction of cell proliferation in siRNA-treated grafts at 14 d postoperatively (P < 0.05).</p><p><b>CONCLUSION</b>The expression of TF in vein grafts can be effectively inhibited by specific siRNAs using a atelocollagen-based nonviral delivery approach in vivo, so that the neointimal thickening can be prevented. Transplants;</p>

Pretreatment of donor dendritic cells with NBD-peptide prolongs mouse cardiac allograft survival / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the effects of NBD-peptide pretreatment of the donor dendritic cells in immune tolerance induction in mouse allograft recipients and investigate the mechanisms.</p><p><b>METHODS</b>BALB/c mouse DCs pretreated with NBD-peptide (NBD-Peptide-DC) were injected into the recipient C57BL/6 mice 7 days before transplantation. Cervical heterotopic heart transplantation model was established using the cuff technique and the cardiac allograft survival time was observed. Pathological analysis were performed to examine the graft injection and the responsiveness of the recipient spleen T cell to the donor alloantigen was determined by mixed lymphocyte reaction (MLR). The serum levels of cytokines were determined using ELISA.</p><p><b>RESULTS</b>The cardiac allograft survival time in the NBD-Peptide-DC-treated group (21.83-/+3.54 days) was significantly longer than that in the Day9-DC group (13.33-/+2.58 days) and PBS-treated group (6.66-/+1.21 days) (P<0.01), with also significantly lower pathological grade for graft rejection (P<0.01). The donor-derived NBD-Peptide-DCs induced alloantigen-specific T-cell hyporesponsiveness. In the NBD-Peptide-DC-treated group, the serum levels of IL-12 and IFN-gamma decreased significantly (P<0.01), but the levels of IL-4 and IL-10 increased significantly (P<0.01).</p><p><b>CONCLUSION</b>Injection of donor-derived NBD-Peptide-DCs can leads to donor-specific tolerance in the transplant recipients, and the induction of recipient T-cell hyporesponsiveness and polarization of Th2 response may play important roles in immune tolerance to cardiac allografts.</p>

Experimental study on mechanical properties of decellularized porcine aortic valve and effects of precoating methods of biological scaffold on histocompatibility / 中华外科杂志

<p><b>OBJECTIVE</b>To observe the mechanical properties of decellularized porcine aortic valve, and to explore the effects of precoating methods of biological scaffold on histocompatibility.</p><p><b>METHODS</b>Fresh porcine aortic valves were decellularized using trypsin, TritonX-100 and nuclease. Treated valves were evaluated by light microscopy, scanning electron microscopy (SEM) and mechanical test. Three groups of scaffold were precoated with phosphate buffered saline (PBS), poly-L-lysine (PLL) and fetal bovine serum (FBS) respectively. Myofibroblasts were seeded onto each scaffold. Light and electron microscopic observation was performed and MTT test was used to examine efficiency of cell attachment.</p><p><b>RESULTS</b>HE stain and SEM showed that cells were almost absent in the treated leaflet. The wave-like collagen together with the whole three-dimensional structure was maintained. Compared with normal valves, the Max-load, Max-stress and elastic modulus decreased while the Max-strain increased (P<0.05). The result of MTT test showed more cells were attached on the valves treated with FBS compared to the other two groups. Histological investigations also confirm that the high degree of cell attachment on the valves precoated with FBS (F=129.26, P=0.000).</p><p><b>CONCLUSIONS</b>Enzyme combined with detergent and nucleases can remove cells from porcine aortic valves. Meanwhile the mechanical properties of these valves may be altered. Precoating porcine aortic valve with FBS is an effective method to improve cell attachment, growth and increasing.</p>

Origin of neointimal cells in autologous vein graft in rat model / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the potential cell sources of neointimal cells in autologous vein graft in rat model.</p><p><b>METHODS</b>Vein graft neointimal cell origins were investigated using a model of vein-to-artery interposition modal. Slides were stained with hematoxylin and eosin, immunohistochemical staining was also performed with primary antibodies alpha-smooth actin or CD34.</p><p><b>RESULTS</b>Neointimal thickening was greater at the proximal ends (65.2 +/- 4.6) microm and, to a lesser extent, distal ends (64.7 +/- 5.3) microm, in comparison to the middle of the graft (63.5 +/- 5.6) microm. Vein-originating cells survived and make a contribution to neointimal formation within the vein graft, mostly adjacent to the lumen, suggesting an intimate association with endothelial cells, donor arterial smooth muscle cells or circulating progenitor cells.</p><p><b>CONCLUSIONS</b>Vein graft neointimal cells arise predominantly from vein-derived endothelial cells, donor arteria smooth muscle cells or circulating progenitor cells. It suggests clinical relevance of stenosis-inhibiting therapies directed at the vein graft or early system pharmacologic administration.</p>

Separation of gastrothoracopagus conjoined twins: 2 cases report / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate reasonable surgical therapy for conjoined twins.</p><p><b>METHODS</b>Two pairs of gastrothoracopagus were admitted in July 2004 and April 2005 respectively. The first pair was separated by emergency surgery for the rupture of umbilical hernia resulting in the exposure of intestines. The thoracic and abdominal wall was repaired with local skin flaps, and the secondary wound was covered with artificial skin. Skin expanders were embedded in thoracic and abdominal wall 2 months after birth in the second pair. The surgical separation was performed one month after. The deficiencies of pericardium, sternum and abdominal wall were reconstructed by allogenic grafting of pericardium, porous polyethylene implant and monofilament polypropylene patch respectively. The thoracic and abdominal wall was repaired with expanded rotation skin flap.</p><p><b>RESULTS</b>The first twins died of respiratory failure and circulatory and respiratory failure 2 hours and 39 hours after the separation respectively. Both of the second pair survived and were discharge after healing.</p><p><b>CONCLUSIONS</b>The separation of gastrothoracopagus should be performed after skin expansion in the interest of the closure of wound. It's better to use porous polyethylene implant and monofilament polypropylene patch to reconstruct the sternum and abdominal wall respectively.</p>

Effects of hydrocortisone sodium succinate on sodium current in human and guinea pig cardiac myocytes / 药学学报

<p><b>AIM</b>To study the effects of hydrocortisone sodium succinate on sodium current in human atrial myocytes and in guinea pig ventricular myocytes.</p><p><b>METHODS</b>Single cardiac myocytes were isolated by enzyme. The effects of hydrocortisone sodium succinate on sodium current (INa) were assessed by applying whole-cell patch clamp techniques.</p><p><b>RESULTS</b>Hydrocortisone sodium succinate (1, 3, 10 micromol x L(-1)) was shown to inhibit INa of both human atrial myocytes and guinea pig ventricular myocytes in concentration dependent manner and the IC50 were 6.97 and 8.74 micromol x L(-1), respectively. The inhibition effects acted quickly (1-3 min) and the maximal activating voltage of INa was not changed in both human and guinea pig cardiac myocytes.</p><p><b>CONCLUSION</b>Hydrocortisone sodium succinate can exhibit inhibitory effects on INa in both human and guinea pig cardiac myocytes, and its inhibitory effects act rapidly, which are not consistent with genomic effects, so there may be nongenomic effects.</p>