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We investigated the optical and electrical properties of red AlGaInP light-emitting diodes (LEDs) as functions of chip size, p-cladding layer thickness, and the number of multi-quantum wells (MQWs). External quantum efficiency (EQE) decreased with decreasing chip size. The ideality factor gradually increased from 1.47 to 1.95 as the chip size decreased from 350 μm to 15 μm. This indicates that the smaller LEDs experienced larger carrier loss due to Shockley-Read-Hall nonradiative recombination at sidewall defects. S parameter, defined as ∂lnL/∂lnI, increased with decreasing chip size. Simulations and experimental results showed that smaller LEDs with 5 pairs of MQWs had over 30% higher IQE at 5 A/cm than the LED with 20 pairs of MQWs. These results show that the optimization of the number of QWs is needed to obtain maximum EQE of micro-LEDs.

Despite the growing interest in adipose tissue as a therapeutic target of metabolic diseases, the identity of adipocyte precursor cells (preadipocytes) and the formation of adipose tissue during embryonic development are still poorly understood. Here, we clarified the identity and dynamic processes of preadipocytes in mouse white adipose tissue during embryogenesis through direct examination, lineage tracing and culture systems. Surprisingly, we found that lipid-lacking but perilipin + or adiponectin + proliferating preadipocytes started to emerge at embryonic day 16.5, and these cells underwent active proliferation until birth. Moreover, these preadipocytes resided as clusters and were distributed along growing adipose vasculatures. Importantly, the embryonic preadipocytes exhibited considerable coexpression of stem cell markers, such as CD24, CD29 and PDGFRα, and a small portion of preadipocytes were derived from PDGFRβ + mural cells, in contrast to the adult preadipocytes present in the stromal vascular fraction. Further analyses with in vitro and ex vivo culture systems revealed a stepwise but dynamic regulation of preadipocyte formation and differentiation during prenatal adipogenesis. To conclude, we unraveled the identity and characteristics of embryonic preadipocytes, which are crucial for the formation and expansion of adipose tissue during embryogenesis.

IMPORTANCE There are limited data from randomized clinical trials comparing propranolol and steroid medication for treatment of infantile hemangioma (IH). OBJECTIVE To determine the efficacy and safety of propranolol compared with steroid as a first-line treatment for IH. DESIGN, SETTING, AND PARTICIPANTS This randomized clinical noninferiority trial tested the efficacy and safety of propranolol vs steroid treatment for IH at a single academic hospital. All participants were diagnosed with IH between June 2013 and October 2014, had normal heart function, and had not been previously treated for IH. INTERVENTIONS The participants were randomly assigned to either the propranolol group or the steroid group. In the propranolol group, the patients were admitted, observed for adverse effects for 3 days after treatment initiation, and then released and treated as outpatients for 16 weeks (2 mg/kg/d). In the steroid group, the patients were seen as outpatients from the beginning and were also treated for 16 weeks (2 mg/kg/d). MAIN OUTCOMES AND MEASURES The primary efficacy variable was the response to treatment at 16 weeks, which was evaluated by the hemangioma volume using magnetic resonance imaging before and at 16 weeks after treatment initiation. While comparing the effect of medication between the groups, we monitored the adverse effects of both drugs. RESULTS A total of 34 patients (15 boys, 19 girls; mean age, 3.3 months; range, 0.3-8.2 months) were randomized to receive either propranolol or steroid treatment (17 in each treatment group). Guardians for 2 patients in the steroid group withdrew their consent, and 1 patient in the propranolol group did not complete the efficacy test. The intention-to-treat analysis, applying multiple imputations, found the treatment response rate in the propranolol group to be 95.65%, and that of the steroid group was 91.94%. Because the difference in response rate between the groups was 3.71%, propranolol was considered noninferior. We found that there was no difference between the groups in safety outcomes. CONCLUSIONS AND RELEVANCE Our trial demonstrated that propranolol was not inferior to steroid with respect to therapeutic effects in IH. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01908972

The authors characterized the dynamic changes occurring in donor adipose-derived stromal cells and fat and recipient tissue by tracing these cellular components following cell-assisted lipotransfer. The authors' findings highlight the therapeutic value of cell-assisted lipotransfer in tissue transplantation.