Highly efficient blue InGaN nanoscale light-emitting diodes.

Indium gallium nitride (InGaN)-based micro-LEDs (µLEDs) are suitable for meeting ever-increasing demands for high-performance displays owing to their high efficiency, brightness and stability1-5. However, µLEDs have a large problem in that the external quantum efficiency (EQE) decreases with the size reduction6-9. Here we demonstrate a blue InGaN/GaN multiple quantum well (MQW) nanorod-LED (nLED) with high EQE. To overcome the size-dependent EQE reduction problem8,9, we studied the interaction between the GaN surface and the sidewall passivation layer through various analyses. Minimizing the point defects created during the passivation process is crucial to manufacturing high-performance nLEDs. Notably, the sol-gel method is advantageous for the passivation because SiO2 nanoparticles are adsorbed on the GaN surface, thereby minimizing its atomic interactions. The fabricated nLEDs showed an EQE of 20.2 ± 0.6%, the highest EQE value ever reported for the LED in the nanoscale. This work opens the way for manufacturing self-emissive nLED displays that can become an enabling technology for next-generation displays.

Melatonin alleviates myocardial dysfunction through inhibition of endothelial-to-mesenchymal transition via the NF-κB pathway.

Endothelial-to-mesenchymal transition (EndMT) is a complex biological process of cellular transdifferentiation by which endothelial cells (ECs) lose their characteristics and acquire mesenchymal properties, leading to cardiovascular remodeling and complications in the adult cardiovascular diseases environment. Melatonin is involved in numerous physiological and pathological processes, including aging, and has anti-inflammatory and antioxidant activities. This molecule is an effective therapeutic candidate for preventing oxidative stress, regulating endothelial function, and maintaining the EndMT balance to provide cardiovascular protection. Although recent studies have documented improved cardiac function by melatonin, the mechanism of action of melatonin on EndMT remains unclear. The present study investigated the effects of melatonin on induced EndMT by transforming growth factor-ß2/interleukin-1ß in both in vivo and in vitro models. The results revealed that melatonin reduced the migratory ability and reactive oxygen species levels of the cells and ameliorated mitochondrial dysfunction in vitro. Our findings indicate that melatonin prevents endothelial dysfunction and inhibits EndMT by activating related pathways, including nuclear factor kappa B and Smad. We also demonstrated that this molecule plays a crucial role in restoring cardiac function by regulating the EndMT process in the ischemic myocardial condition, both in vessel organoids and myocardial infarction (MI) animal models. In conclusion, melatonin is a promising agent that attenuates EC dysfunction and ameliorates cardiac damage compromising the EndMT process after MI.

Visible-Light Photoredox-Catalyzed Giese Reaction of α-Silyl Ethers with Various Michael Acceptors.

We developed a photocatalyzed Giese reaction of various weakly activated Michael acceptors with a neutral silicon-based radical precursor and applied it at large-scale using a continuous flow reactor. The developed method successfully overcomes the substrate scope limitations of previous studies, shows good functional groups tolerance, and affords good to excellent yields. On the basis of mechanistic studies, we propose a reaction mechanism that involves an in situ generated alkoxymethyl radical via single-electron oxidation of α-trimethylsilyl-substituted ethers.

Regulation of Inflammation-Mediated Endothelial to Mesenchymal Transition with Echinochrome a for Improving Myocardial Dysfunction.

Endothelial-mesenchymal transition (EndMT) is a process by which endothelial cells (ECs) transition into mesenchymal cells (e.g., myofibroblasts and smooth muscle cells) and induce fibrosis of cells/tissues, due to ischemic conditions in the heart. Previously, we reported that echinochrome A (EchA) derived from sea urchin shells can modulate cardiovascular disease by promoting anti-inflammatory and antioxidant activity; however, the mechanism underlying these effects was unclear. We investigated the role of EchA in the EndMT process by treating human umbilical vein ECs (HUVECs) with TGF-ß2 and IL-1ß, and confirmed the regulation of cell migration, inflammatory, oxidative responses and mitochondrial dysfunction. Moreover, we developed an EndMT-induced myocardial infarction (MI) model to investigate the effect of EchA in vivo. After EchA was administered once a day for a total of 3 days, the histological and functional improvement of the myocardium was investigated to confirm the control of the EndMT. We concluded that EchA negatively regulates early or inflammation-related EndMT and reduces the myofibroblast proportion and fibrosis area, meaning that it may be a potential therapy for cardiac regeneration or cardioprotection from scar formation and cardiac fibrosis due to tissue granulation. Our findings encourage the study of marine bioactive compounds for the discovery of new therapeutics for recovering ischemic cardiac injuries.

Therapeutic outcomes of embolotherapy of extremity bone intraosseous arteriovenous malformation with ethanol, coils, and n-butyl cyanoacrylate.

OBJECTIVE: We evaluated the therapeutic outcomes of embolotherapy for bone arteriovenous malformations (AVMs) affecting the extremities using ethanol, coils, and n-butyl cyanoacrylate (NBCA). METHODS: We reviewed the data from 36 patients (18 males, 18 females; mean age 25 years; age range, 1-64 years) with bone AVMs affecting their extremities who had undergone embolotherapy using ethanol, coils, and NBCA from December 1996 to July 2019. Of the 36 patients, 19 had had pure bone AVMs and 17 mixed bone and soft tissue (MBS) AVMs. Embolotherapy was performed using direct puncture or a transvenous or an intra-arterial approach (range, 1-18 procedures; mean, 5 procedures). During the 178 embolotherapy procedures, ethanol was used in all 36 patients, except for 1. Coils were used in 14 patients, and NBCA and a lipiodol mixture in 9 patients. The therapeutic outcomes were evaluated by the clinical symptom response and the degree of devascularization on follow-up angiography or computed tomography. The major and minor complications were also evaluated. RESULTS: The clinical success (cure or markedly improvement) rate of embolotherapy for pure bone AVMs was significantly better than that for the MBS AVMs (88% vs 18%; P < .001). The complete devascularization rate of the bone AVM component of the MBS AVMs was 71%; however, the cure rate of the MBS AVMs was 0% owing to the remaining soft tissue AVMs. Of the 36 patients, 12 experienced complications, including 11 minor (2 skin bullae formation and 10 transient peripheral nerve injury) and 1 major (longstanding nerve palsy). CONCLUSIONS: Embolotherapy for bone AVMs affecting the extremities using ethanol, coils, and an NBCA mixture is effective and safe for the resolution or improvement of symptoms, especially in those with pure bone AVMs.

Percutaneous radiologic gastrostomy with single gastropexy: outcomes in 636 patients.

OBJECTIVES: This study aimed to assess the technical success and overall complication rate of percutaneous radiologic gastrostomy (PRG) with single gastropexy using a separate tract from that used for tube placement. METHODS: From January 2014 to December 2018, 636 patients (469 men, 167 women; mean age 66.8 years; age range, 22-98 years) underwent PRG using single gastropexy at a tertiary center. Preprocedural computed tomography (CT) was recommended if there were no data on the location of the stomach on previous CT. After a single anchor was applied, the PRG tube was inserted through a separate tract from that used for tube placement. The technical success rate and major and minor complications were retrospectively reviewed. The number of patients and percentages were used as descriptive statistics for evaluating the complication rate. RESULTS: The technical success rate of PRG with single gastropexy was 99.2% (631/636). There were 32 complications among the 631 procedures. There were 19 (3.0%) major complications, including peritonitis (n = 7), migration (n = 5), infection (n=4), malposition (n = 2), and bleeding (n = 1). There were 13 (2.1%) minor complications, including local infection (n = 11), malfunction (n = 1), and pneumoperitoneum (n = 1). The overall complication rate within 30 days of PRG placement was 4.1% (26/631). CONCLUSIONS: PRG with single gastropexy using a separate tract from that used for tube placement is technically feasible with a low complication rate. KEY POINTS: • Percutaneous radiologic gastrostomy with single gastropexy using a separate tract from that used for tube placement is technically feasible. • Complications including peritonitis and bleeding were comparatively low with the conventional technique.

Peroxisome Proliferator-Activated Receptor Gamma Modulator Promotes Neonatal Mouse Primordial Follicle Activation In Vitro.

Peroxisome proliferator-activated receptor gamma (PPARγ) is known as a regulator of cellular functions, including adipogenesis and immune cell activation. The objectives of this study were to investigate the expression of PPARγ and identify the mechanism of primordial follicle activation via PPARγ modulators in mouse ovaries. We first measured the gene expression of PPARγ and determined its relationship with phosphatase and tensin homolog (PTEN), protein kinase B (AKT1), and forkhead box O3a (FOXO3a) expression in neonatal mouse ovaries. We then incubated neonatal mouse ovaries with PPARγ modulators, including rosiglitazone (a synthetic agonist of PPARγ), GW9662 (a synthetic antagonist of PPARγ), and cyclic phosphatidic acid (cPA, a physiological inhibitor of PPARγ), followed by transplantation into adult ovariectomized mice. After the maturation of the transplanted ovaries, primordial follicle growth activation, follicle growth, and embryonic development were evaluated. Finally, the delivery of live pups after embryo transfer into recipient mice was assessed. While PPARγ was expressed in ovaries from mice of all ages, its levels were significantly increased in ovaries from 20-day-old mice. In GW9662-treated ovaries in vitro, PTEN levels were decreased, AKT was activated, and FOXO3a was excluded from the nuclei of primordial follicles. After 1 month, cPA-pretreated, transplanted ovaries produced the highest numbers of oocytes and polar bodies, exhibited the most advanced embryonic development, and had the greatest blastocyst formation rate compared to the rosiglitazone- and GW9662-pretreated groups. Additionally, the successful delivery of live pups after embryo transfer into the recipient mice transplanted with cPA-pretreated ovaries was confirmed. Our study demonstrates that PPARγ participates in primordial follicle activation and development, possibly mediated in part by the PI3K/AKT signaling pathway. Although more studies are required, adapting these findings for the activation of human primordial follicles may lead to treatments for infertility that originates from poor ovarian reserves.

Percutaneous cryoablation for perivascular hepatocellular carcinoma: Therapeutic efficacy and vascular complications.

OBJECTIVES: To evaluate the therapeutic efficacy of and vascular complications associated with percutaneous cryoablation for the treatment of perivascular HCC. METHODS: Between August 2015 and September 2017, 58 consecutive patients (48 men, 10 women; mean age, 61.1 years; age range, 44-84 years) who underwent percutaneous cryoablation were included. All patients had a single perivascular HCC (mean size, 1.3 cm; Barcelona clinic liver cancer-stage 0 or A) that was in contact with hepatic vessels, ≥ 3 mm or larger in axial diameter. Local tumour progression (LTP) was estimated by the Kaplan-Meier method. In addition, several procedure-related vascular complications were evaluated immediately after treatment and during follow-up CT: peritumoral vessel thrombosis; infarction; aggressive intrasegmental recurrence (AIR) (the simultaneous development of ≥ 3 nodular or infiltrative tumours). The follow-up CT was performed in all patients 1 month after the procedure, and every 3 months thereafter. RESULTS: The median follow-up period was 22 months (range, 3-29 months). The technical success rate of cryoablation was 96.6% (56/58). The 1- and 2-year cumulative LTP rates were 3.6% and 14.6%, respectively. Although peritumoral vessel thrombosis occurred in 6.9% of cases (4/58), no cases of hepatic infarction were observed and AIR did not develop during follow-up. Half of the thombi in the peritumoral vessels immediately after cryoablation disappeared on follow-up CT images. CONCLUSION: Cryoablation could be an effective tool for the treatment of perivascular HCC with a very low risk of vascular complications. KEY POINTS: • Cryoablation allowed a high technical success rate for perivascular HCC. • Only 6.9% developed peritumoral vessel thrombosis without major vascular complications like infarction. • Two-year cumulative LTP rate was 14.6%, without aggressive tumour recurrence on follow-up.

Echinochrome A Attenuates Cerebral Ischemic Injury through Regulation of Cell Survival after Middle Cerebral Artery Occlusion in Rat.

Of late, researchers have taken interest in alternative medicines for the treatment of brain ischemic stroke, where full recovery is rarely seen despite advanced medical technologies. Due to its antioxidant activity, Echinochrome A (Ech A), a natural compound found in sea urchins, has acquired attention as an alternative clinical trial source for the treatment of ischemic stroke. The current study demonstrates considerable potential of Ech A as a medication for cerebral ischemic injury. To confirm the effects of Ech A on the recovery of the injured region and behavioral decline, Ech A was administered through the external carotid artery in a rat middle cerebral artery occlusion model after reperfusion. The expression level of cell viability-related factors was also examined to confirm the mechanism of brain physiological restoration. Based on the results obtained, we propose that Ech A ameliorates the physiological deterioration by its antioxidant effect which plays a protective role against cell death, subsequent to post cerebral ischemic stroke.

Multiple Combination of Angelica gigas Extract and Mesenchymal Stem Cells Enhances Therapeutic Effect.

Alternative medicines attract attention because stroke is rarely expected to make a full recovery with the most advanced medical technology. Angelica gigas (AG) is a well-known herbal medicine as a neuroprotective agent. The present study introduced mesenchymal stem cells (MSCs) to identify for the advanced treatment of the cerebrovascular disease. The objective of this research is validation of the enhanced effects of multiple combined treatment of AG extract with MSCs on stroke through angiogenesis. Our results confirmed that AG extract with MSCs improved the neovascularization increasing expression of angiogenesis-regulated molecules. The changes of brain and the behavioral ability showed the increased effects of AG extract with MSCs. As a result, AG extract and MSCs may synergistically increase the therapeutic potential by enhancing neovascularization. This mixed approach provides a new experimental protocol of herbal medicine therapy for the treatment of a variety of diseases including stroke, trauma, and spinal cord injury.

Decision making processes of women who seek elective oocyte cryopreservation.

PURPOSE: The aim of this study is to analyze women's opinions and their decision making processes regarding elective oocyte cryopreservation (OC). METHODS: One hundred twenty-four women who had elective OC counseling at the CHA Seoul Fertility Center were asked to complete a survey after their first visit. Data collection regarding age, marital status, monthly income, occupation, religion, reproductive history, questions about the participant's view on their own fecundity, and future parenthood were included. The modified Reproductive Concerns After Cancer scale and the Decisional Conflict Scale were used for analysis. RESULTS: The participants' mean age was 37.1 ± 4.8 years old. Eighty-six percent of the participants had regular periods. Ninety-two percent thought it was important to have their own biological offspring, and 86% were willing to pursue OC. Forty-nine percent appeared to have high DCS scores regarding making a decision of OC. Sixty-eight percent pursued OC, and the mean number of oocytes cryopreserved per patient was 10.5 ± 8.3. Multivariate analysis revealed that age was the only factor associated with high DCS scores (P = 0.002). Feeling less fertile than other women of same age and low DCS scores were the factors associated with pursuing OC (P = 0.02 and 0.004, respectively) after adjusting for possible confounding factors, including age. CONCLUSIONS: Older women had more difficulties in making decisions about OC. Adjusting for age, women who thought that they were less fertile than other women of same age and those with lower decisional conflict were more likely to pursue OC. Further studies should focus on the validation of older women's decisional conflicts regarding OC.

Ninjurin1 Assembles Into a Homomeric Protein Complex Maintained by N-linked Glycosylation.

Ninjurin1 (Ninj1) is a cell surface protein known as a homophilic adhesion molecule. Previous studies have shown a trans-interaction of Ninj1 between immune cells and endothelial cells; however, little is known about Ninj1 modification and structure in the cis-interaction. We showed that Ninj1 assembles into a homomeric complex via a cis-interaction mediated by the intracellular region and N-glycosylation at Asn60 . We identified cis-interaction between Ninj1 proteins using CFP- and YFP-tagged Ninj1 by Förster resonance energy transfer using a confocal microscope and fluorescence-activated cell sorter. We further observed the Ninj1 homomeric complexes composed of two to six monomeric Ninj1 molecules by a formaldehyde cross-linking assay. Co-immunoprecipitation assays with epitope-tagged truncated Ninj1 suggested that the intracellular region encompassing Leu101 -Ala110 participates in Ninj1 homomer assembly. Ninj1 N-glycosylation was characterized by treatment of tunicamycin and substitution of Asn to Gln or Ala. Fluorescence-activated cell sorting-based Förster resonance energy transfer assays further demonstrated that N-glycosylation is indispensable for the Ninj1 cis-interaction, and a formaldehyde cross-linking assay confirmed that interruption of N-glycosylation by Asn substitution disrupted Ninj1 homomeric complex formation. In silico analysis revealed that Ninj1 is highly conserved in vertebrates and that the conserved sequence contains an N-glycosylation motif and cis-interacting intracellular region, which participate in Ninj1 homomer assembly. Taken together, these data show that Ninj1 assembles into a homomeric protein complex and that N-glycosylation is a prerequisite for Ninj1 homomer assembly. J. Cell. Biochem. 118: 2219-2230, 2017. © 2017 Wiley Periodicals, Inc.

Exogenous miRNA-146a Enhances the Therapeutic Efficacy of Human Mesenchymal Stem Cells by Increasing Vascular Endothelial Growth Factor Secretion in the Ischemia/Reperfusion-Injured Heart.

Adult stem cells have been studied as a promising therapeutic modality for the functional restoration of the damaged heart. In the present study, a strategy for enhancing the angiogenic efficacy of human mesenchymal stem cells (hMSCs) using micro-RNA was examined. We investigated whether micro-RNA-146a (miR-146a) influences the secretion of vascular endothelial growth factor (VEGF) and angiogenesis of MSCs. Our data indicated that miR-146a-transfected hMSCs (hMSCmiR-146a) decreased the expression of neurofibromin 2, an inhibitor of p21-activated kinase-1 (PAK1). miR-146a also increased the expression of Ras-related C3 botulinum toxin substrate 1 and PAK1, which are known to induce VEGF expression, and the formation of vascular branches was increased in hMSCmiR-146a compared to hMSCs treated with VEGF. VEGF and p-Akt were increased in hMSCmiR-146a. Furthermore, injection of hMSCmiR-146a after ischemia/reperfusion (I/R) injury led to a reduction of fibrosis area and increased VEGF expression, confirming the regenerative capacity such as reparative angiogenesis in the infarcted area. Cardiac functions in I/R injury were improved following injection of hMSCmiR-146a compared to the I/R group. Taken together, these data suggest that miR-146 is a novel microRNA that regulates VEGF expression, and its use may be an effective strategy for enhancing the therapeutic efficacy of hMSC transplantation into the I/R-injured heart.

Alternative new mesenchymal stem cell source exerts tumor tropism through ALCAM and N-cadherin via regulation of microRNA-192 and -218.

Gliomas are the most common type of malignant primary brain tumors. Some treatments of gliomas exist, but they are rarely curative. Mesenchymal stem cells (MSCs) are emerging as potential modes of targeted cancer therapy owing to their capacity for homing toward tumor sites. It has been proposed that MSCs derived from various sources, such as bone marrow, adipose tissue and umbilical cord blood, can be used as cell-based therapy for brain tumors. Here, MSCs obtained from the synovial fluid of osteoarthritis or rheumatoid arthritis patients were investigated as therapeutic candidates. Specifically, we compared migratory and adhesive abilities, as well as expression levels of related genes and microRNA in bone marrow derived-MSCs (BMMSCs), adipose derived-MSCs (ADMSCs), and synovial fluid derived-MSCs (SFMSCs) after treatment with conditioned medium from gliomas. Migration and adhesion of SFMSCs increased through upregulation of the activated lymphocyte cell adhesion molecule (ALCAM) and N-cadherin by microRNA-192 and -218 downregulation, similar to BMMSCs and ADMSCs. Migratory capacities of all types of MSCs were evaluated in vivo, and SFMSCs migrated intensively toward gliomas. These results suggest that SFMSCs have potential for use in cell-based antitumor therapies.

Side-Chain-Induced Rigid Backbone Organization of Polymer Semiconductors through Semifluoroalkyl Side Chains.

While high-mobility p-type conjugated polymers have been widely reported, high-mobility n-type conjugated polymers are still rare. In the present work, we designed semifluorinated alkyl side chains and introduced them into naphthalene diimide-based polymers (PNDIF-T2 and PNDIF-TVT). We found that the strong self-organization of these side chains induced a high degree of order in the attached polymer backbones by forming a superstructure composed of "backbone crystals" and "side-chain crystals". This phenomenon was shown to greatly enhance the ordering along the backbone direction, and the resulting polymers thus exhibited unipolar n-channel transport in field-effect transistors with remarkably high electron mobility values of up to 6.50 cm(2) V(-1) s(-1) and with a high on-off current ratio of 10(5).

Therapeutic Potential of Differentiated Mesenchymal Stem Cells for Treatment of Osteoarthritis.

Osteoarthritis (OA) is a chronic, progressive, and irreversible degenerative joint disease. Conventional OA treatments often result in complications such as pain and limited activity. However, transplantation of mesenchymal stem cells (MSCs) has several beneficial effects such as paracrine effects, anti-inflammatory activity, and immunomodulatory capacity. In addition, MSCs can be differentiated into several cell types, including chondrocytes, osteocytes, endothelia, and adipocytes. Thus, transplantation of MSCs is a suggested therapeutic tool for treatment of OA. However, transplanted naïve MSCs can cause problems such as heterogeneous populations including differentiated MSCs and undifferentiated cells. To overcome this problem, new strategies for inducing differentiation of MSCs are needed. One possibility is the application of microRNA (miRNA) and small molecules, which regulate multiple molecular pathways and cellular processes such as differentiation. Here, we provide insight into possible strategies for cartilage regeneration by transplantation of differentiated MSCs to treat OA patients.

PTEN loss-mediated Akt activation increases the properties of cancer stem-like cell populations in prostate cancer.

OBJECTIVE: To demonstrate that the PTEN/PI3K/Akt/NF-κB pathway plays an important role in regulating the prostate cancer stem-like cell population by upregulating ABCG2. METHODS: Targeted PTEN knockdown in human prostate DU145 and 22Rv1 cells using a small interfering RNA were confirmed by immunoblot analysis using antibodies of PTEN, phospho-Akt, Akt, and α-tubulin. Knockdown PTEN DU145 and 22Rv1 cells were augmented, and the stem cell-like properties were examined by cell viability and tumor sphere formation and treated by Akt IV inhibitor to provide the signal transduction pathway. Luciferase activity assays were performed. RESULTS: The knockdown of PTEN in prostate cancer cell lines increased the stem-like properties of the cells, including their sphere-forming ability, stem cell population number, epithelial-mesenchymal transition-related gene expression, and ABCG2 expression. Additionally, PTEN expression was highly associated with elevated expression of phospho-Akt. Treatment with an Akt inhibitor suppressed the PTEN-mediated effects on the properties of these stem-like cells as well as drug resistance, ABCG2 expression, and the NF-κB pathway. CONCLUSION: The loss of PTEN in prostate cancer cells resulted in an increased PI3K/Akt pathway. Due to the Akt activation, PTEN loss may play an important role in prostate cancer by promoting cancer stemness through a mechanism that involves enhanced NF-κB signaling.

Complete and Incomplete Alcohol Sclerotherapy for Treatment of Symptomatic Hepatic Cysts: Comparison of Volume Reduction and Clinical Outcomes.

Background: The purpose of this study was to compare the efficacy of incomplete alcohol sclerotherapy with complete treatment for hepatic cysts. Methods: From 2005 to 2021, a total of 80 patients (19 males, 61 females; median age 65 years; age range, 42-86 years) who underwent alcohol sclerotherapy for symptomatic benign hepatic cysts were enrolled and retrospectively reviewed. Complete treatment was defined as injecting 25-33% of the aspirated cyst volume with alcohol in 2-3 cycles, with a maximum of 100 mL per cycle. The overall volume reduction rate was compared between the complete and incomplete treatment groups. The response, based on cystic volume reduction, was classified as a complete regression (CR), near-complete regression (NCR), partial regression (PR), or no response (NR). CR and NCR were considered objective responses. Among 80 patients with 85 hepatic cysts, 26 patients with 29 hepatic cysts received incomplete treatment. Results: The overall volume reduction rate was not significantly different between the complete and incomplete treatment groups (94.39% vs. 95.47%, respectively, p = 0.623). The CR and NCR groups showed a significantly higher rate of symptom improvement than the PR and NR groups (p = 0.043). Conclusions: In conclusion, the efficacy of incomplete alcohol sclerotherapy was not inferior to that of complete treatment.

Insights into structural defect formation in individual InP/ZnSe/ZnS quantum dots under UV oxidation.

InP/ZnSe/ZnS quantum dots (QDs) stand as promising candidates for advancing QD-organic light-emitting diodes (QLED), but low emission efficiency due to their susceptibility to oxidation impedes applications. Structural defects play important roles in the emission efficiency degradation of QDs, but the formation mechanism of defects in oxidized QDs has been less investigated. Here, we investigated the impact of diverse structural defects formation on individual QDs and propagation during UV-facilitated oxidation using high-resolution (scanning) transmission electron microscopy. UV-facilitated oxidation of the QDs alters shell morphology by the formation of surface oxides, leaving ZnSe surfaces poorly passivated. Further oxidation leads to the formation of structural defects, such as dislocations, and induces strain at the oxide-QD interfaces, facilitating In diffusion from the QD core. These changes in the QD structures result in emission quenching. This study provides insight into the formation of structural defects through photo-oxidation, and their effects on emission properties of QDs.