Venous Blood Derivatives as FBS-Substitutes for Mesenchymal Stem Cells: A Systematic Scoping Review

Optimizing aseptic and serum milieu for the isolation of human whole umbilical cord tissue-derived mesenchymal stem cells

Background

Mesenchymal stem cells (MSCs) have become an attractive tool for tissue engineering and targets in clinical transplantation due to their regeneration potential and immune-suppressive capacity. The human umbilical cord, which is discarded at birth, can provide an inexhaustible source of stem cells for therapy. They are reported to contain immune privilege cells which may be suitable for allogenic-based therapies. However, the use of MSCs for therapeutic application is based on their subsequent large-scale in vitro expansion. A fast and efficient protocol for the generation of large quantities of MSCs is required to meet the clinical demand and biomedical research needs.

Results

MSCs were isolated from the umbilical cord by explants and enzymatic digestion and cultured in the appropriate growth medium resulted in the propagation of more than 1X 108 cells within 15 days from the single umbilical cord.

Conclusion

The isolation efficiency, cell yield, colony-forming unit fibroblast (CFU-F), growth kinetics, phenotypic characteristics of UCMSCs were determined.

Platelet-Rich Plasma as an Alternative to Xenogeneic Sera in Cell-Based Therapies: A Need for Standardization

There has been an explosion in scientific interest in using human-platelet-rich plasma (PRP) as a substitute of xenogeneic sera in cell-based therapies. However, there is a need to create standardization in this field. This systematic review is based on literature searches in PubMed and Web of Science databases until June 2021. Forty-one studies completed the selection criteria. The composition of PRP was completely reported in less than 30% of the studies. PRP has been used as PRP-derived supernatant or non-activated PRP. Two ranges could be identified for platelet concentration, the first between 0.14 × 10⁶ and 0.80 × 10⁶ platelets/µL and the second between 1.086 × 10⁶ and 10 × 10⁶ platelets/µL. Several studies have pooled PRP with a pool size varying from four to nine donors. The optimal dose for the PRP or PRP supernatant is 10%. PRP or PRP-derived supernatants a have positive effect on MSC colony number and size, cell proliferation, cell differentiation and genetic stability. The use of leukocyte-depleted PRP has been demonstrated to be a feasible alternative to xenogeneic sera. However, there is a need to improve the description of the PRP preparation methodology as well as its composition. Several items are identified and reported to create guidelines for future research.

Interventions to reduce bruxism in children and adolescents: a systematic scoping review and critical reflection

The aim of the present study was to perform a critical reflection about intervention options for bruxism reduction in children and adolescents. Search was conducted based on the PICO-structured question: "What are the intervention options to reduce bruxism in children/adolescents?". No language, year, or study design restrictions were imposed. Studies reporting interventions to reduce bruxism in children (< 10) and adolescents (10 to 19 years old) were included. Reviews and letters to editors were not included. From 2723 records, 17 papers were included. Included studies were primarily randomized clinical trials performed in Brazil (35.3%) and using different criteria for the diagnosis of bruxism. Reduction in self-reported bruxism and headaches associated with bruxism were observed in studies that used medications (hydroxyzine/trazodone/flurazepam), occlusal splints, orthodontic interventions, and psychological and physical therapy interventions. Reduction in Rhythmic Masticatory Muscle Activity was observed with the use of the occlusal splint and in orthodontic interventions. Alternative treatments (medicinal extracts such as Melissa officinalis-L) have shown inconclusive results.Conclusions: Several intervention options are available to inhibit or reduce bruxism activity. The respective indication, contraindications, and side effects of each treatment option must be assessed individually and carefully, taking into account that bruxism is not considered a disorder in otherwise healthy individuals.What is known• Biological and psychological factors have been strongly correlated to the development of bruxism• Bruxism prevalence ranging from 6 to 50% in childrenWhat is new• Reduction in self-reported bruxism and headaches associated with bruxism were observed in studies that used medication (Hydroxyzine/ Trazodone/ Flurazepam), occlusal splints, orthodontic interventions, psychological, and physical therapy interventions• A reduction in Rhythmic Masticatory Muscle Activity was observed with the use of the occlusal splint and orthodontic interventions. Alternative treatments (medicinal extracts such as Melissa officinalis L) show inconclusive results in respect of the reduction in bruxism.

Bone, Periodontal and Dental Pulp Regeneration in Dentistry: A Systematic Scoping Review

Abstract The aim of presented systematic scoping review was to investigate the actual and future clinical possibilities of regenerative therapies and their ability to regenerate bone, periodontal and pulp with histological confirmation of the nature of formed tissue. Electronic search was conducted using a combination between Keywords and MeSH terms in PubMed, Scopus, ISI-Web of Science and Cochrane library databases up to January 2016. Two reviewers conducted independently the papers judgment. Screened studies were read following the predetermined inclusion criteria. The included studies were evaluated in accordance with Arksey and O’Malley’s modified framework. From 1349 papers, 168 completed inclusion criteria. Several characterized and uncharacterized cells used in Cell Therapy have provided bone regeneration, demonstrating bone gain in quantity and quality, even as accelerators for bone and periodontal regeneration. Synthetic and natural scaffolds presented good cell maintenance, however polyglycolid-polylactid presented faster resorption and consequently poor bone gain. The Growth Factor-Mediated Therapy was able to regenerate bone and all features of a periodontal tissue in bone defects. Teeth submitted to Revascularization presented an increase of length and width of root canal. However, formed tissues not seem able to deposit dentin, characterizing a repaired tissue. Both PRP and PRF presented benefits when applied in regenerative therapies as natural scaffolds. Therefore, most studies that applied regenerative therapies have provided promising results being possible to regenerate bone and periodontal tissue with histological confirmation. However, pulp regeneration was not reported. These results should be interpreted with caution due to the short follow-up periods.