Vascularized Sural Nerve Graft, Fascial Free Flap, and Regenerative Peripheral Nerve Interface in the Setting of Recurrent Thigh Liposarcoma: A Case Report.

Background: There is no clear consensus in the literature regarding clinical indications for vascularized nerve grafts. Most studies indicate that vascularized nerve grafting, rather than non-vascularized nerve grafting, is indicated for nerve gaps of greater than 7 cm. Vascularized nerve grafts are superior to non-vascularized nerve grafts because they possess an independent blood supply. However, not all nerve injuries can be repaired via vascularized nerve grafts. Methods: A 32-year-old female received a fascial free flap and vascularized sural nerve graft after having multiple reresections of a recurrent thigh liposarcoma. Results: A 25-cm segment of the sural nerve was isolated alongside the lesser saphenous vein and intervening fascia. The free fascial flap was subsequently reversed and placed into the thigh. Vascular anastomoses were created, and the sural nerve was anastomosed to the peroneal nerve. A small portion of muscle from the thigh was wrapped around tibial nerve fascicles of the sciatic nerve to create a regenerative nerve interface. Conclusions: Benefits of vascularized sural nerve graft compared with other vascularized nerve grafts include negligible sensory loss at the donor site and a nerve graft that can be designed on itself due to its vast length. Additionally, vascularized sural nerve grafts provided a better rate of axonal regeneration, rate of electromyographic return, and motor and sensory outcome compared with non-vascularized sural nerve grafts.

The 510(k) Third Party Review Program: Promise and Potential.

Every year, the Food and Drug Administration (FDA) clears approximately 3,000 medical devices for marketing via the 510(k) pathway. These constitute 99% of all devices approved for human use and includes the premarket review of many devices incorporating newer technology such as artificial intelligence (AI), machine learning (ML), and other software. As the complexity of these novel technologies and the number of applications is expected to increase in the coming years, statutory changes such as the 2016 21st Century Cures Act, regulations, and guidance documents have increased both the volume and complexity of device review. Thus, the ability to streamline the review of less complex, low-to-moderate risk devices through the 510(k) pathway will maximize the FDA's capability to address other important, future-oriented regulatory questions. For over twenty five years, third party review organizations have served a defined function to assist with the review of 510(k) applications for a set of enumerated device classes. This paper reviews the history of FDA device regulation, the evolution of the 510(k) review pathway, and the recent history of the 510(k) third party review program. Finally, the paper addresses policy concerns from all stakeholders - including the FDA - along with policy suggestions to improve the third party review program and FDA device regulation writ large.

Network of clinically-relevant lncRNAs-mRNAs associated with prognosis of hepatocellular carcinoma patients.

Long non-coding RNAs (lncRNAs) are often aberrantly expressed in Hepatocellular Carcinoma (HCC). We hypothesize that lncRNAs modulate HCC prognoses through differential deregulation of key lncRNAs affecting important gene network in key cancer pathways associated with pertinent clinical phenotype. Here, we present a novel approach integrating lncRNA-mRNA expression profiles with clinical characteristics to identify lncRNA signatures in clinically-relevant co-expression lncRNA-mRNA networks residing in pertinent cancer pathways. Notably one network, associated with poorer prognosis, comprises five up-regulated lncRNAs significantly correlated (|Pearson Correlation Coefficient|≥ 0.9) with 91 up-regulated genes in the cell-cycle and Rho-GTPase pathways. All 5 lncRNAs and 85/91 (93.4%) of the correlated genes were significantly associated with higher tumor-grade while 3/5 lncRNAs were also associated with no tumor capsule. Interestingly, 2/5 lncRNAs that are correlated with numerous genes in this oncogenic network were experimentally shown to up-regulate genes involved in cell-cycle and transcriptional regulation. Another network comprising 4 down-regulated lncRNAs and 8 down-regulated metallothionein-family genes are significantly associated with tumor invasion. The identification of these key lncRNAs signatures that deregulate important network of genes in key cancer pathways associated with pertinent clinical phenotype may facilitate the design of novel therapeutic strategies targeting these 'master' regulators for better patient outcome.