Vascularization of PEGylated fibrin hydrogels increases the proliferation of human iPSC-cardiomyocytes

Hydrogels in cardiac tissue engineering: application and challenges

Cardiovascular disease remains the leading cause of global mortality. Current stem cell therapy and heart transplant therapy have limited long-term stability in cardiac function. Cardiac tissue engineering may be one of the key methods for regenerating damaged myocardial tissue. As an ideal scaffold material, hydrogel has become a viable tissue engineering therapy for the heart. Hydrogel can not only provide mechanical support for infarcted myocardium but also serve as a carrier for various drugs, bioactive factors, and cells to increase myocardial contractility and improve the cell microenvironment in the infarcted area, thereby improving cardiac function. This paper reviews the applications of hydrogels and biomedical mechanisms in cardiac tissue engineering and discusses the challenge of clinical transformation of hydrogel in cardiac tissue engineering, providing new strategies for treating cardiovascular diseases.

Comparison of double antibiotic chitosan hydrogel scaffold with platelet-rich fibrin in regeneration in immature necrotic permanent teeth - Randomized controlled trial

Background

Fibrin, a natural hydrogel, can act as scaffold for tissue regeneration. Antibiotic-loading of hydrogels can create an infection-free environment for stem cell proliferation and maturation.

Aim

To compare regenerative endodontic potential of three groups (antibiotic-loaded hydrogel, chitosan-loaded hydrogel, and double antibiotic-loaded chitosan hydrogel) in immature necrotic permanent teeth with platelet rich fibrin (PRF).

Materials and Methods

Fifty-six immature necrotic teeth with periapical lesions were included in simple randomized parallel-controlled superiority trial. Patients aged 10-35 years were assigned into four groups based on scaffolds used: Group 1 (PRF), Group 2 (double antibiotic-loaded [metronidazole and ciprofloxacin] chitosan hydrogel), Group 3 (double antibiotic-loaded hydrogel), and Group 4 (chitosan-loaded hydrogel). One patient per group was lost to follow-up. Regenerative outcomes (change in apex size, root length, radicular dentin thickness, and periapical healing) were assessed at 12 months, through double-blinding and compared postprocedure using cone-beam computed tomography.

Statistical Analysis

Based on normality distribution, change in apex size (ANOVA test) while root length, radicular dentin thickness (Kruskal-Wallis test), and periapical healing (paired t-test) were used.

Results

Group 2 showed superior regenerative outcomes (P = 0.001) compared to groups 1, 4 after 12 months, and no significant difference with Group 3.

Conclusion

Double antibiotic-loaded chitosan produced significantly superior outcomes compared to PRF in promoting apexogenesis in immature permanent teeth with necrosed pulp.

The Role of Stem Cells in the Treatment of Cardiovascular Diseases

Cardiovascular diseases (CVDs) are the leading cause of death and include several vascular and cardiac disorders, such as atherosclerosis, coronary artery disease, cardiomyopathies, and heart failure. Multiple treatment strategies exist for CVDs, but there is a need for regenerative treatment of damaged heart. Stem cells are a broad variety of cells with a great differentiation potential that have regenerative and immunomodulatory properties. Multiple studies have evaluated the efficacy of stem cells in CVDs, such as mesenchymal stem cells and induced pluripotent stem cell-derived cardiomyocytes. These studies have demonstrated that stem cells can improve the left ventricle ejection fraction, reduce fibrosis, and decrease infarct size. Other studies have investigated potential methods to improve the survival, engraftment, and functionality of stem cells in the treatment of CVDs. The aim of the present review is to summarize the current evidence on the role of stem cells in the treatment of CVDs, and how to improve their efficacy.