Mesenchymal stem cell tissue engineering: techniques for isolation, expansion and application

Mesenchymal stem cells (MSCs) are undifferentiated multipotent cells which reside in various human tissues and have the potential to differentiate into osteoblasts, chondrocytes, adipocytes, fibroblasts and other tissues of mesenchymal origin. In the human body they could be regarded as readily available reservoirs of reparative cells capable to mobilize, proliferate and differentiate to the appropriate cell type in response to certain signals. These properties have triggered a variety of MSC-based therapies for pathologies including nonunions, osteogenesis imperfecta, cartilage damage and myocardial infarction. The outcome of these approaches is influenced by the methodologies and materials used during the cycle from the isolation of MSCs to their re-implantation. This review article focuses on the pathways that are followed from the isolation of MSCs, expansion and implantation.     

Evaluation of healthcare professionals’ understanding of eponymous maneuvers and mnemonics in emergency obstetric care provision

Objective

To evaluate whether eponymous maneuvers and mnemonics taught for the management of shoulder dystocia, vaginal breech delivery, and uterine inversion were remembered and understood in practice.

Methods

A questionnaire was distributed to obstetricians and midwives collecting information about the HELPERR and PALE SISTER mnemonics. Three extended matching questions evaluated participants’ knowledge of the correct maneuvers, with their matching eponyms, used in the management of shoulder dystocia, vaginal breech delivery, and uterine inversion.

Results

Of the 112 participants, 90% were familiar with the HELPERR mnemonic, with 79% using it in their practice. Of those who used it, only 32% could correctly decipher it (P = 0.032). PALE SISTER was mostly unfamiliar. The percentages of correct maneuvers used for managing shoulder dystocia, breech delivery, and uterine inversion were 84.6%, 58.3%, and 28.6%, respectively. However, the eponyms were correctly matched to their maneuvers in only 33.3%, 14.3%, and 0% of cases, respectively (P < 0.01).

Conclusion

The meanings of the mnemonics for obstetric emergencies were frequently recalled incorrectly. This, together with the poor correlation between knowledge of maneuvers and their eponyms, limits their usefulness and indicates that teaching should focus on learning without relying on mnemonics and eponyms.     

Cost analysis and outcomes of simple elbow dislocations

AIM: To evaluate the management, clinical outcome and cost implications of three different treatment regimes for simple elbow dislocations.METHODS: Following institutional board approval, we performed a retrospective review of all consecutive patients treated for simple elbow dislocations in a Level I trauma centre between January 2008 and December 2010. Based on the length of elbow immobilisation (LOI), patients were divided in three groups (Group I, < 2 wk; Group II, 2-3 wk; and Group III, > 3 wk). Outcome was considered satisfactory when a patient could achieve a pain-free range of motion ≥ 100° (from 30° to 130°). The associated direct medical costs for the treatment of each patient were then calculated and analysed.RESULTS: We identified 80 patients who met the inclusion criteria. Due to loss to follow up, 13 patients were excluded from further analysis, leaving 67 patients for the final analysis. The mean LOI was 14 d (median 15 d; range 3-43 d) with a mean duration of hospital engagement of 67 d (median 57 d; range 10-351 d). Group III (prolonged immobilisation) had a statistically significant worse outcome in comparison to Group I and II (P = 0.04 and P = 0.01 respectively); however, there was no significant difference in the outcome between groups I and II (P = 0.30). No statistically significant difference in the direct medical costs between the groups was identified.CONCLUSION: The length of elbow immobilization doesn’t influence the medical cost; however immobilisation longer than three weeks is associated with persistent stiffness and a less satisfactory clinical outcome.     

Biology of mesenchymal stem cells

Mesenchymal stem cells are present in many human tissues and serve as a readily available source of undifferentiated cells being capable to form specific tissues like bone, cartilage, fat, muscle and tendon. They represent an attractive and promising field in tissue regeneration and engineering for treatment applications in a wide range of trauma and orthopaedic conditions. This article covers the most important aspects of recent research data demonstrating the combination of physiological properties of mesenchymal stem cells (MSCs) and applications in the clinical setting.     

Tissue regeneration. The past, the present and the future

Tissue engineering has been a topic of extensive research over the last years. The ability of human body to regenerate tissue loss such as bone, cartilage, nerves, skin and muscle is limited leading often to amputations of limbs or functional disability. The isolation of mesenchymal stem cells (MSCs) and later the embryonic stem cells in conjunction with the advances made in cellular biology, tissue engineering, genetics and recombinant technology has initiated the development of new techniques and new therapeutic strategies allowing treatment of many pathological conditions providing restoration of tissue continuity and function.