Category: General

Front Bioeng Biotechnol. 2022 Sep 9;10:1008664. doi: 10.3389/fbioe.2022.1008664. eCollection 2022.

ABSTRACT

The bioprosthetic heart valves (BHVs) are the best option for the treatment of valvular heart disease. Glutaraldehyde (Glut) is commonly used as the golden standard reagent for the crosslinking of BHVs. However, the obvious defects of Glut, including residual aldehyde toxicity, degradation and calcification, increase the probability of valve failure in vivo and motivated the exploration of alternatives. Thus, the aim of this study is to develop a non-glutaraldehyde hybrid cross-linking method composed of Neomycin Trisulfate, Polyethylene glycol diglycidyl ether and Tannic acid as a substitute for Glut, which was proven to reduce calcification, degradation, inflammation of the biomaterial. Evaluations of the crosslinked bovine pericardial included histological and ultrastructural characterization, biomechanical performance, biocompatibility and structural stability test, and in vivo anti-inflammation and anti-calcification assay by subcutaneous implantation in juvenile Sprague Dawley rats. The results revealed that the hybrid crosslinked bovine pericardial were superior to Glut crosslinked biomaterial in terms of better hydrophilicity, thermodynamics stability, hemocompatibility and cytocompatibility, higher Young’s Modulus, better stability and resistance to enzymatic hydrolysis, and lower inflammation, degradation and calcification levels in subcutaneous implants. Considering all above performances, it indicates that the hybrid cross-linking method is appropriate to replace Glut as the method for BHV preparation, and particularly this hybrid crosslinked biomaterials may be a promising candidate for next-generation BHVs.

PMID:36159659 | PMC:PMC9500414 | DOI:10.3389/fbioe.2022.1008664

Xenotransplantation. 2022 Sep 13:e12774. doi: 10.1111/xen.12774. Online ahead of print.

ABSTRACT

INTRODUCTION: Current bioprosthetic heart valve replacement options are limited by structural valvular deterioration (SVD) due to an immune response to the xenogenic scaffold. Autologous mesenchymal stem cell (MSC) recellularization is a method of concealing xenogenic scaffolds, preventing recipient immune recognition of xenogenic tissue heart valves, and potentially leading to reduction in SVD incidence. The purpose of this study is to examine the effects of autologous MSC recellularized tissue on the immune response of human whole blood to bovine pericardium (BP). We hypothesized that autologous MSC recellularization of BP will result in reduced pro-inflammatory cytokine production equivalent to autologous human pericardium.

METHODS: Bone marrow, human pericardium, and whole blood were collected from adult patients undergoing elective cardiac surgery. Decellularized BP underwent recellularization with autologous MSCs, followed by co-incubation with autologous whole blood. Immunohistochemical, microscopic, and quantitative immune analysis approaches were used.

RESULTS: We demonstrated that native BP, exposed to human whole blood, results in significant TNF-α and IL1β production. When decellularized BP is recellularized with autologous MSCs and exposed to whole blood, there is a significant reduction in TNF-α and IL1β production. Importantly, recellularized BP exposed to whole blood had similar production of TNF-α and IL1β when compared to autologous human pericardium exposed to human whole blood.

CONCLUSION: Our results suggest that preventing initial immune activation with autologous MSC recellularization may be an effective approach to decrease the recipient immune response, preventing recipient immune recognition of xenogeneic tissue engineered heart valves, and potentially leading to reduction in SVD incidence.

PMID:36098060 | DOI:10.1111/xen.12774

Braz J Cardiovasc Surg. 2022 Jun 8. doi: 10.21470/1678-9741-2020-0716. Online ahead of print.

ABSTRACT

INTRODUCTION: The aim of our study was to compare the primary closure (PRC) and patch angioplasty closure (PAC) of carotid artery following carotid endarterectomy (CEA).

METHODS: Data of patients who underwent CEA in the period from January 2005 to June 2020 were reviewed through files. Demographic characteristics, information about the operation, and postoperative follow-up outcomes of the patients were compared.

RESULTS: Of the 144 CEA cases included in the study, PRC and PAC were applied to 62 (43.7%) and 82 (56.3%) patients, respectively, for the carotid artery closure. Duration of surgery and carotid artery clamping time were not different between the PRC and PAC groups (106.73±17.13 minutes vs. 110.48±20.67 minutes, P=0.635; 24.25±11.56 minutes vs. 25.19±8.99 minutes, P=0.351, respectively). Postoperative respiratory impairment was more common in the PRC group (P=0.012); however, nerve injuries (P=0.254), surgical wound hematomas (P=0.605), surgical site infections (P=0.679), and mortality (P=0.812) were not significantly different between the groups. During the mean patient follow-up time of 26.13±19.32 months, restenosis was more common in the PRC group than in the PAC group (n=26, 41.9% vs. n=4, 4.9%, respectively; P=0.003). Frequencies of stroke (n=4, 2.8% vs. n=2, 2.4%, respectively; P=0.679), transient ischemic attacks (n=2, 1.4% vs. n=0, 0%, respectively; P=0.431), and mortality (n=4, 6.5% vs. n=4, 4.9%, respectively; P=0.580) were not significantly different between the PRC and PAC groups.

CONCLUSION: We are of the opinion that the PAC method is effective and safe for carotid artery closure in patients undergoing CEA.

PMID:35675495 | DOI:10.21470/1678-9741-2020-0716