Effects of small-fiber neuropathy induced by resiniferatoxin on skin healing and axonal regrowth after burn

Towards the development of sensation-enabled skin substitutes

Recent advances in cell and biofabrication technologies have contributed to the development of complex human organs. In particular, several skin substitutes are being generated using tissue engineering and regenerative medicine (TERM) technologies. However, recent studies mainly focus on the restoration of the dermis and epidermis layers rather than the regeneration of a fully functional innervated skin organ. Innervation is a critical step in functional tissue repair which has been overlooked in the current TERM studies. In the current study, we highlight the importance of sensation in the skin as the largest sensory organ in the human body. In large non-healing skin wounds, the skin sensation is severely diminished or completely lost and ultimately lead to chronic pain and wound healing process interruption. Current therapeutics for restoring skin sensation after trauma are limited. Recent regenerative medicine-based studies could successfully induce neural networks in skin substitutes, but the effectiveness of these technologies in enhancing sensory capability needs further investigation.

Meta-Analysis: Outcomes of Surgical and Medical Management of Diabetic Foot Osteomyelitis

BACKGROUND

The aim of this study was to evaluate clinical outcomes in the published literature on medical and surgical management of diabetic foot osteomyelitis (DFO).

METHODS

A PubMed and Google Scholar search of articles relating to DFO was performed over the dates of January 1931 to January 2020. Articles that involved Charcot arthropathy, case reports, small case series, review articles, commentaries, nonhuman studies, and non-English articles were excluded. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool was used to rate the bias of each study. A meta-analysis was performed using random-effects and inverse variance methods. The search yielded 1192 articles. After review and the removal of articles that did not meet inclusion criteria, 28 articles remained. Eighteen articles were related to the medical management of DFO and 13 articles were related to surgical management. Three articles looked at a combination of medical and surgical management and were included in both groups. Heterogeneity was evaluated using Cochran Q, I 2, τ2, and τ.

RESULTS

The average success rate was 68.2% (range, 17.0%-97.3%) for medical treatment and 85.7% (range, 65.0%-98.8%) for surgical and medical treatment. There were significant inconsistencies in accounting for peripheral arterial disease and peripheral neuropathy. There was significant heterogeneity in outcomes between studies. However, there was a high rate of successful treatment and a wide range between patients with medical treatment and combined surgical and medical treatment.

CONCLUSIONS

Additional properly designed prospective studies with gold-standard references for diagnosing osteomyelitis are needed to help determine whether medical management of DFO can be successful without surgical intervention.

Adipose-Derived Mesenchymal Stromal Cells in Regenerative Medicine: State of Play, Current Clinical Trials, and Future Prospects

Significance: Wound healing is a complex process involving pain and inflammation, where innervation plays a central role. Managing wound healing and pain remains an important issue, especially in pathologies such as excessive scarring (often leading to fibrosis) or deficient healing, leading to chronic wounds. Recent Advances: Advances in therapies using mesenchymal stromal cells offer new insights for treating indications that previously lacked options. Adipose-derived mesenchymal stromal cells (AD-MSCs) are now being used to a much greater extent in clinical trials for regenerative medicine. However, to be really valid, these randomized trials must imperatively follow strict guidelines such as consolidated standards of reporting trials (CONSORT) statement. Indeed, AD-MSCs, because of their paracrine activities and multipotency, have potential to cure degenerative and/or inflammatory diseases. Combined with their relatively easy access (from adipose tissue) and proliferation capacity, AD-MSCs represent an excellent candidate for allogeneic treatments. Critical Issues: The success of AD-MSC therapy may depend on the robustness of the biological functions of AD-MSCs, which requires controlling source heterogeneity and production processes, and development of biomarkers that predict desired responses. Several studies have investigated the effect of AD-MSCs on innervation, wound repair, or pain management separately, but systematic evaluation of how those effects could be combined is lacking. Future Directions: Future studies that explore how AD-MSC therapy can be used to treat difficult-to-heal wounds, underlining the need to thoroughly characterize the cells used, and standardization of preparation processes are needed. Finally, how this a priori easy-to-use cell therapy treatment fits into clinical management of pain, improvement of tissue healing, and patient quality of life, all need to be explored.

Fabrication of separable microneedles with phase change coating for NIR-triggered transdermal delivery of metformin on diabetic rats

To enhance the compliance of drug delivery for patients, the novel near-infrared (NIR) light-triggered and separable microneedles (MNs) have been developed in this work. Firstly, prussian blue nanoparticles (PB NPs) as the photo-thermal conversion factor and metformin as the hypoglycemic drug were embedded into the separable arrowheads, which consisted by poly (vinyl alcohol) and sucrose (PVA/Suc). The arrowheads of MNs were located on soluble solids supporting substrates that produced by poly(vinyl pyrrolidone) (PVP). Lauric acid (LA) as the phase transition coating covered on the surface of the MNs due to its lower phase transition temperature (~44 °C). Then, the separable arrowheads could be left into the skin because of the absorbing the interstitial fluid (IF) by the solid supporting substrates. With the irradiation of NIR light, LA could be melted due to the role of PB NPs in photo-thermal conversion, thus releasing the metformin from arrowheads. Compared with the traditional subcutaneous injections, the hypoglycemic effect was evaluated by the drug-release behaviors induced by NIR in vivo. The results showed that metformin could be allowed to on-demand release under the NIR irradiation. And the as-obtained MNs exhibited a good hypoglycemic effect, hypotoxicity and low inflammation reaction compared with those of traditional subcutaneous injections. The results indicate that the fabricated MNs have the potential treatment for diabetes due to their safety, convenience and painlessness.

Natural products as a perspective for cancer pain management: A systematic review

BACKGROUND

Cancer is the leading cause of death in the world and one of the main symptoms affecting these individuals is chronic pain, which must be evaluated and treated in its various components. Several drugs are currently used, but beyond the high cost, they have harmful side effects to patients or are transitorily effective. Ergo, there is a need to look for new options for cancer pain relief. Natural products (NPs) present themselves as strong candidates for the development of new drugs for the treatment of chronic pain, such as cancer pain.

PURPOSE

This systematic review aimed to summarize current knowledge about the analgesic profile of NPs in cancer pain.

METHODS

The search included PubMed, Scopus and Web of Science (from inception to June 2018) sought to summarize the articles studying new proposals with NPs for the management of oncological pain. Two independent reviewers extracted data on study characteristics, methods and outcomes.

RESULTS

After an extensive survey, 21 articles were selected, which described the analgesic potential of 15 natural compounds to relieve cancer pain. After analyzing the data, it can be suggested that these NPs, which have targets in central and peripheral mechanisms, are interesting candidates for the treatment of cancer pain for addressing different pharmacological mechanisms (even innovative), but ensuring the safety of these compounds is still a challenge. Likewise, the cannabinoids compounds leave the front as the most promising compounds for direct applicability due to the clinical studies that have already been developed and the background already established about these effects on chronic pain.

CONCLUSION

Regarding these findings, it can be concluded that the variability of possible biological sites of action is strategic for new perspectives in the development of therapeutic proposals different from those available in the current market.