Particulated autologous cartilage transplantation for the treatment of osteochondral lesion of the talus: can the lesion cartilage be recycled?

Aims: Osteochondral lesions of the talus (OLT) are a common cause of disability and chronic ankle pain. Many operative treatment strategies have been introduced; however, they have their own disadvantages. Recently lesion repair using autologous cartilage chip has emerged therefore we investigated the efficacy of particulated autologous cartilage transplantation (PACT) in OLT. Methods: We retrospectively analyzed 32 consecutive symptomatic patients with OLT who underwent PACT with minimum one-year follow-up. Standard preoperative radiography and MRI were performed for all patients. Follow-up second-look arthroscopy or MRI was performed with patient consent approximately one-year postoperatively. Magnetic resonance Observation of Cartilage Repair Tissue (MOCART) score and International Cartilage Repair Society (ICRS) grades were used to evaluate the quality of the regenerated cartilage. Clinical outcomes were assessed using the pain visual analogue scale (VAS), Foot Function Index (FFI), and Foot Ankle Outcome Scale (FAOS). Results: All patients had ICRS grade IV cartilage lesions, except for one (ICRS grade III). The paired MOCART scores significantly improved from 42.5 (SD 1.53) to 63.5 (SD 22.60) (p = 0.025) in ten patients. Seven patients agreed to undergo second-look arthroscopy; 5 patients had grade I (normal) ICRS scores and two patients had grade II (nearly normal) ICRS scores. VAS, FFI, and all subscales of FAOS were significantly improved postoperatively (p ≤ 0.003). Conclusion: PACT significantly improved the clinical, radiological, and morphological outcomes of OLT. We consider this to be a safe and effective surgical method based on the short-term clinical results of this study.

Skin Perfusion Pressure Predicts Early Wound Healing After Endovascular Therapy in Chronic Limb Threatening Ischaemia.

OBJECTIVE: Skin perfusion pressure (SPP) has been proposed as a method to predict wound healing in chronic limb threatening ischaemia (CLTI). However, studies regarding the impact of SPP before and after endovascular therapy (EVT) on wound healing are limited. This study sought to evaluate the predictive value of SPP for early wound healing in CLTI treated by EVT. METHODS: Between January 2018 and June 2020, 236 limbs (172 patients) with CLTI that underwent SPP measurement before and after EVT were included. SPP was measured before and 24 - 48 hours after the procedure. Early wound healing was defined as the achievement of complete epithelisation of all wounds without major amputation within three months of EVT. RESULTS: Early wound healing was achieved in 145 (61.4%) limbs after EVT. Baseline SPP (44.1 ± 21.0 mmHg vs. 33.5 ± 21.7 mmHg; p < .001) and post-procedural SPP (61.8 ± 18.5 mmHg vs. 37.4 ± 19.9 mmHg; p < .001) were significantly higher in the wound healing (+) group than in the wound non-healing (-) group. The area under the receiver operating characteristics curve for early wound healing was 0.82 for post-procedural SPP with a cutoff value of 50 mmHg (sensitivity 74.5%, specificity 78.0%). The early wound healing rate was significantly higher with a post-procedural SPP ≥ 50 mmHg compared with a SPP < 50 mmHg (84.4% vs. 35.0%; p < .001). CONCLUSION: Post-procedural SPP with a cutoff value of 50 mmHg was capable of predicting early wound healing after EVT in CLTI.

Allogeneic keratinocyte for intractable chronic diabetic foot ulcers: A prospective observational study.

Chronic diabetic foot ulcers (DFUs) are a common problem in patients with diabetes and are often difficult to treat. The application of newly developed dressing material in patients with chronic DFUs has been reported to be effective. The purpose of this study was to evaluate the usefulness of allogeneic keratinocyte treatment for chronic DFUs. We performed weekly allogeneic keratinocyte treatment for up to 12 weeks in 71 patients with intractable DFUs. We investigated healing rate, wound-healing velocity, and time to 50% wound size reduction and analysed factors affecting ulcer healing. Fifty-six patients (78.8%) had complete wound healing. Forty-six patients (64.7%) showed complete healing within an average of 6.1 weeks, and 10 patients (14.1%) showed partial healing with an average 35.5% reduction vs initial size at the end of follow up. The 10 patients who showed partial healing continued to receive treatment after the 12-week study period. The mean time to complete wound healing was 7.8 weeks. Fifteen patients (21.1%) experienced treatment failure because of infection, local necrosis, no change in ulcer size, or osteomyelitis during the follow-up period. No adverse events were observed. Allogeneic keratinocyte treatment is effective for chronic, difficult-to-treat DFUs.

Rapid fabrication of complex 3D extracellular microenvironments by dynamic optical projection stereolithography.

The topographic features of the extracelluar matrix (ECM) lay the foundation for cellular behavior. A novel biofabrication method using a digital-mirror device (DMD), called dynamic optical projection stereolithography (DOPsL) is demonstrated. This robust and versatile platform can generate complex biomimetic scaffolds within seconds. Such 3D scaffolds have promising potentials for studying cell interactions with microenvironments in vitro and in vivo.

Selective sebaceous gland electrothermolysis as a treatment for acne: a prospective pilot study.

Although many therapeutic options exist for acne, relapse often occurs after treatment is stopped. Some preliminary evidence suggests that selective electrothermolysis of the sebaceous glands may represent a novel therapeutic intervention. This trial was conducted to evaluate the efficacy and tolerability of selective sebaceous gland electrothermolysis for the treatment of facial acne. Twelve patients with facial acne were enrolled, all of whom underwent three sessions of therapy. During each session, a 1.5-mm long needle with 0.45-mm of base insulation was inserted into pores of acne lesions. Upon insertion, a high-frequency electrical current was applied for 0.25-0.50 seconds, for a total output of 40 W. Each treatment session took approximately 30-60 minutes. Subject response to therapy was evaluated at one month and 12 months after the final treatment. All the enrolled subjects completed the study and all reported satisfaction with treatment results. In all cases, a reduction in inflammatory and noninflammatory lesion counts was observed after three sessions of selective electrothermolysis, although a few small papules and comedones persisted in several areas of untreated facial skin. Mean lesion reduction at one month after the final treatment was 98.14% for inflammatory lesions and 83.09% for noninflammatory lesions. Clinical success was achieved in the majority of patients (seven of 12 patients) at one month after the second treatment and in all patients at one month after the final treatment. All patients reported transient post-treatment erythema, which faded after a few days. Clinically evident relapse occurred in two of 12 patients (16.7%) one year after the final treatment session. Selective sebaceous gland electrothermolysis can be a safe and effective method of achieving consistent remission in acne.

Optimality in the variation of average branching angle with generation in the human bronchial tree.

In the human bronchial tree the branching angle becomes larger with generation or for the smaller branches. Previous theories based on single parameter optimization have not been successful at all in predicting the consistent increasing trend of branching angle with continued bifurcation. In this study a new theory for the optimality of the branching angle is proposed, which is based on the optimization between dual competing performances, the maximum space-filling capability at the expense of minimum energy loss. A large-angle branching gives an effect of delivering air into a new direction away from the preceding airways. It then has an effect of utilizing the lung volume with better uniformity, but at the same time inevitably requires a high pressure loss. It is shown in this paper that the ever increasing branching angle with generation can be well explained as the optimum branching structure where the dual opposing performance of space filling and pressure loss is optimized. In estimating the pressure loss, branching loss is considered in addition to the Poiseuille loss. Change of predicted optimum branching angle with generation shows an excellent agreement with the observed data found in the human conducting airways.

Fluid-dynamic optimality in the generation-averaged length-to-diameter ratio of the human bronchial tree.

It is shown in this paper that the nearly constant length-to-diameter ratio observed with conducting airways of human bronchial tree can be explained based on the fluid dynamic optimality principle. In any branched tube there are two pressure loss mechanisms, one for wall friction in the tube section and the other for flow division in the branching section, and there exists an optimal length-to-diameter ratio which minimizes the total pressure loss for a branched tube in laminar flow condition. The optimal length-to-diameter ratio predicted by the pressure loss minimization shows an excellent agreement with the length-to-diameter ratios found in the human conducting airways.