Protocol for electrocatalytic hydrogenation of 5-hydroxymethylfurfural using H and flow cells.

Recently, there has been a growing interest in using sustainable energy to decrease lignin monomers to generate high-value-added products. Here, we present a protocol for electrocatalytic hydrogenation of 5-hydroxymethylfurfural. We describe steps for catalyst preparation, performing electrocatalytic experiments, high-performance liquid chromatography analysis, and in situ infrared reflection-absorption spectroscopy testing. The synthesized catalyst used in this reaction exhibits enhanced selectivity and Faradaic efficiency in NaClO4 solution. For complete details on the use and execution of this protocol, please refer to Zhang et al.1.

Selective electrocatalytic hydrogenation of lignocellulose-derived 5-hydroxymethylfurfural with superior productivities.

Recently, valorization of biomass to value-added chemicals has drawn increasing attention due to carbon neutrality and sustainability. 5-Hydroxymethylfurfural is an important lignocellulose-derived biomass molecule. Herein, we have demonstrated the efficient electrocatalytic hydrogenation of 5-hydroxymethylfurfural to value-added 2,5-bis(hydroxymethyl)furan. An optimized electrolyzer with a highly electrolyte-permeable Pd cathode well balanced the selectivity, faradaic efficiency, and productivity. We have achieved high selectivity (97%) and faradaic efficiency (72%) at 50 mA cm-2 current density, and a record high productivity of 0.923 mmol cm-2·h-1 at 100 mA cm-2 current density, ∼2 times advanced compared with the best productivity in prior reports. We applied in situ infrared reflection-absorption spectroscopy to investigate the electrode-potential-dependent reaction pathways and mechanism, confirming that the highly selective hydrogenation of HMF is due to the tilted adsorption geometry through carbonyl group bonding to the surface of electrode. This work offers an opportunity for the sustainable electrocatalytic valorization of renewable lignocellulose-derived biomass with superior productivities approaching industrial level.

Flap reconstruction of distal lower extremity wounds in diabetic patients.

Lower extremity diabetic wounds have been a challenge to clinical surgeons because of the higher risk of limb ischemia, soft-tissue infection, and soft-tissue loss caused by the pathology of the disease. In the published data, the most commonly used reconstruction techniques include pedicled flaps, microsurgical muscle or musculocutaneous flaps, and microsurgical fasciocutaneous or perforator flaps. However, there is still no consensus about which type of flap should be preferred among various reconstructive options. It is therefore the aim of this study to review current articles describing distal lower extremity flap reconstruction in patients with diabetes to survey reported results from the literature.

Integra acellular collagen as a vascular carrier for skin flap prefabrication in rats.

In this study, the feasibility of Integra acellular collagen used as a vascular carrier in skin flap prefabrication was examined. In all, 20 Sprague--Dawley rats were randomly divided into 3 groups. The saphenous vascular bundle was used as the vascular carrier. In group 1 (n = 8), an arteriovenous fistula was made by anastomosis of distal saphenous artery and vein. An Integra patch (2 × 3 cm²) was placed underneath the vascular bundle. In group 2 (n = 6), an Integra patch was placed on the top of the saphenous vessels, which remained intact. In group 3 (n = 6), an arteriovenous fistula was made without Integra implant. Two weeks after the initial management, a skin flap (2 × 3 cm² in size) was raised and replaced in each group. The survival of the flaps and histology were evaluated at 7 days after flap replacement. The results showed that the average survival area in group 1 was 98% ± 2%. No flap survival was observed in group 2. The mean survival area in group 3 was 29% ± 6%. The differences among all 3 groups were significant (P < 0.05). Although the mean survival area in group 3 was significantly lower than that in group 1 (P < 0.001), it was significantly higher than that in group 2. Histology showed that the Integra patch was incorporated into the adjacent connective tissue, and increased amounts of neovascularization were seen between the collagenous sheets and dermis in group 1. In conclusion, this study demonstrated that Integra acellular collagen can incorporate into the adjacent tissue as a vascular carrier and induce angiogenesis in flap prefabrication. This biomaterial can provide a scaffold for supporting and enhancing the survival of a vascular prefabricated skin flap. The results indicate that this material is an ideal biomaterial for flap prefabrication and may be used for this clinical purpose in the future.