Patterned Si thin film electrodes for enhancing structural stability

A patterned film (electrode) with lozenge-shaped Si tiles could be successfully fabricated by masking with an expanded metal foil during film deposition. Its electrochemical properties and structural stability during the charge-discharge process were examined and compared with those of a continuous (conventional) film electrode. The patterned electrode exhibited a remarkably improved cycleability (75% capacity retention after 120 cycles) and an enhanced structural stability compared to the continuous electrode. The good electrochemical performance of the patterned electrode was attributed to the space between Si tiles that acted as a buffer against the volume change of the Si electrode

Trans-Differentiation of Neural Stem Cells: A Therapeutic Mechanism Against the Radiation Induced Brain Damage

Radiation therapy is an indispensable therapeutic modality for various brain diseases. Though endogenous neural stem cells (NSCs) would provide regenerative potential, many patients nevertheless suffer from radiation-induced brain damage. Accordingly, we tested beneficial effects of exogenous NSC supplementation using in vivo mouse models that received whole brain irradiation. Systemic supplementation of primarily cultured mouse fetal NSCs inhibited radiation-induced brain atrophy and thereby preserved brain functions such as short-term memory. Transplanted NSCs migrated to the irradiated brain and differentiated into neurons, astrocytes, or oligodendrocytes. In addition, neurotrophic factors such as NGF were significantly increased in the brain by NSCs, indicating that both paracrine and replacement effects could be the therapeutic mechanisms of NSCs. Interestingly, NSCs also differentiated into brain endothelial cells, which was accompanied by the restoration the cerebral blood flow that was reduced from the irradiation. Inhibition of the VEGF signaling reduced the migration and trans-differentiation of NSCs. Therefore, trans-differentiation of NSCs into brain endothelial cells by the VEGF signaling and the consequential restoration of the cerebral blood flow would also be one of the therapeutic mechanisms of NSCs. In summary, our data demonstrate that exogenous NSC supplementation could prevent radiation-induced functional loss of the brain. Therefore, successful combination of brain radiation therapy and NSC supplementation would provide a highly promising therapeutic option for patients with various brain diseases

Assessment of the Suitability of Trauma Triage According to Physiological Criteria in Korea

Purpose A trauma center project for treating patients with trauma has been established in Korea. A trauma team is activated based on the Centers for Disease Control and Prevention (CDC) field triage Step 1 for patient triage. Here, we determined if the currently applied criteria were appropriate for the triage of patients with trauma in Korea. Methods This retrospective study included patients who were taken to the regional trauma center from January 1, 2016 to December 31, 2019, and were registered in the Korean Trauma database. The rates for undertriage and overtriage were calculated from the in-field and in-hospital triage according to the CDC guidelines Step 1. Results Among the 9,383 patients transferred to the trauma center, 3,423 were directly transferred from the site and were investigated. The overall rates for undertriage and overtriage of these patients were 28.13% and 30.35%, respectively. For the patients who received in-field triage and were directly transferred to the trauma center, the rates for undertriage and overtriage were 27.92% and 32.39%, and 25.92% and 29.11% for in-hospital triage, respectively. The concordance rate of triage was 87.09%. Conclusion The current use of in-hospital triage physiological criteria as set out in the CDC guidelines Step 1, indicated an undertriage rate which was high and an overtriage rate within the acceptable range. Further studies on triaging patients with trauma are warranted. Improvements in the guidelines of the trauma center project are necessary and this needs to be supported by resources and training for field personnel

High-quantum yield alloy-typed core/shell CdSeZnS/ZnS quantum dots for bio-applications

Abstract Background Quantum dots (QDs) have been used as fluorophores in various imaging fields owing to their strong fluorescent intensity, high quantum yield (QY), and narrow emission bandwidth. However, the application of QDs to bio-imaging is limited because the QY of QDs decreases substantially during the surface modification step for bio-application. Results In this study, we fabricated alloy-typed core/shell CdSeZnS/ZnS quantum dots (alloy QDs) that showed higher quantum yield and stability during the surface modification for hydrophilization compared with conventional CdSe/CdS/ZnS multilayer quantum dots (MQDs). The structure of the alloy QDs was confirmed using time-of-flight medium-energy ion scattering spectroscopy. The alloy QDs exhibited strong fluorescence and a high QY of 98.0%. After hydrophilic surface modification, the alloy QDs exhibited a QY of 84.7%, which is 1.5 times higher than that of MQDs. The QY was 77.8% after the alloy QDs were conjugated with folic acid (FA). Alloy QDs and MQDs, after conjugation with FA, were successfully used for targeting human KB cells. The alloy QDs exhibited a stronger fluorescence signal than MQD; these signals were retained in the popliteal lymph node area for 24h. Conclusion The alloy QDs maintained a higher QY in hydrophilization for biological applications than MQDs. And also, alloy QDs showed the potential as nanoprobes for highly sensitive bioimaging analysis. Graphical Abstrac