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2.
J Control Release ; 367: 768-778, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38341178

RESUMO

Immunotherapy based on adoptive transfer of natural killer (NK) cells is a promising strategy for circumventing the limitations of cancer treatments. However, components of the immunosuppressive tumor microenvironment (TME), such as transforming growth factor-beta (TGF-ß), compromise the therapeutic efficacy of NK cells significantly. To address these limitations, we developed a novel method of engineering NK cells for adaptive transfer. The method is based on nanogels that serve two functions: (1) they overcome the TGF-ß-mediated stress environment of the TME, and (2) they enhance the direct anti-tumor activity of NK cells. Previously, we demonstrated that cationic compounds such as 25 K branched polyethylenimine (25 K bPEI) prime NK cells, putting them in a 'ready-to-fight' state. Based on these findings, we designed nanogels that have two primary characteristics: (1) they encapsulate galunisertib (Gal), which is used clinically to inhibit TGF-ß receptor activity, thereby blocking TGF-ß signaling; and (2) they provide cells with a surface coating of 25 K bPEI. When grown in culture medium containing TGF-ß, nanogel-treated NK cells demonstrated greater migration ability, degranulation activity, and cytotoxicity towards cancer cells than untreated NK cells. Additionally, the in vivo efficacy of nanogel-treated NK cells against PC-3 xenografts was significantly greater than that of Chem_NK cells primed by 25 K bPEI alone. These findings suggest that Gal-loaded 25 K bPEI-coated nanogels exert anti-tumor effects via chemical priming, as well suppressing the effects of TGF-ß on NK cells. We also expect 25 K bPEI-based nanogels to have great potential to overcome the suppressive effects of the TME through their NK cell-priming activity and delivery of the desired chemicals.


Assuntos
Citotoxicidade Imunológica , Polietilenoglicóis , Polietilenoimina , Fator de Crescimento Transformador beta , Humanos , Nanogéis , Fator de Crescimento Transformador beta/farmacologia , Linhagem Celular Tumoral , Células Matadoras Naturais , Microambiente Tumoral
3.
Int J Mol Sci ; 25(3)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38338992

RESUMO

Knee osteoarthritis (OA), an age-related degenerative disease characterized by severe pain and disability, is treated using polynucleotides (PNs) and hyaluronic acid (HA). The intra-articular (IA) injection of HA has been studied extensively in both animal models and in humans; however, the efficacy and mechanisms of action remain unclear. In addition, there has been a paucity of research regarding the use of PN alone or in combination with HA in OA. To investigate the effect of the combined injection of PN and HA in vivo, pathological and behavioral changes were assessed in an OA model. Anterior cruciate ligament transection and medial meniscectomy were performed in Sprague-Dawley rats to create the OA animal model. The locomotor activity improved following PNHA injection, while the OARSI grade improved in the medial tibia and femur. In mild OA, TNFα levels decreased histologically in the PN, HA, and PNHA groups but only the PNHA group showed behavioral improvement in terms of distance. In conclusion, PNHA exhibited anti-inflammatory effects during OA progression and improved locomotor activity regardless of the OARSI grade.


Assuntos
Ácido Hialurônico , Osteoartrite do Joelho , Ratos , Humanos , Animais , Ácido Hialurônico/farmacologia , Polinucleotídeos/farmacologia , Polinucleotídeos/uso terapêutico , Ratos Sprague-Dawley , Osteoartrite do Joelho/tratamento farmacológico , Ligamento Cruzado Anterior/cirurgia , Injeções Intra-Articulares
4.
Chronobiol Int ; 41(1): 1-9, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38108132

RESUMO

This cross-sectional study examined the relationship of mid-sleep time (MST) with depression, quality of life, and sleep deprivation. This study included 173 284 adults aged ≥ 19 years who participated in the 2018 Korea Community Health Survey. The Patient Health Questionnaire-9 for depression, EuroQol-5 dimension for health-related quality of life, and the Pittsburgh Sleep Quality Index for MST, daytime sleepiness, and sleep quality were used. Regression and logistic regression analysis was used for complex sample analysis. The results showed that individuals with later MST had a higher risk of depression, poor quality of life, poor sleep quality, and excessive daytime sleepiness than intermediate-type individuals, whereas earlier MST was associated with good sleep quality in the total population. This association was significant in both men and women. The later type was associated with all items of health-related quality of life in both men and women. These findings suggest that the later type is a significant predictor of mental health, quality of life, sleep quality, and daytime sleepiness. Identifying an individual's mid-sleep time may help tailor interventions and treatment strategies that optimize sleep, mental health outcomes, and quality of life.


Assuntos
Distúrbios do Sono por Sonolência Excessiva , Transtornos do Sono-Vigília , Masculino , Adulto , Humanos , Feminino , Privação do Sono , Qualidade de Vida , Depressão/epidemiologia , Saúde Pública , Estudos Transversais , Ritmo Circadiano , Sono , Inquéritos e Questionários , República da Coreia
6.
Acta Neuropathol Commun ; 11(1): 142, 2023 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-37667395

RESUMO

Dystrophic neurites (DNs) are abnormal axons and dendrites that are swollen or deformed in various neuropathological conditions. In Alzheimer's disease (AD), DNs play a crucial role in impairing neuronal communication and function, and they may also contribute to the accumulation and spread of amyloid beta (Aß) in the brain of AD patients. However, it is still a challenge to understand the DNs of specific neurons that are vulnerable to Aß in the pathogenesis of AD. To shed light on the development of radiating DNs, we examined enriched dystrophic hippocampal axons in a mouse model of AD using a three-dimensional rendering of projecting neurons. We employed the anterograde spread of adeno-associated virus (AAV)1 and conducted proteomic analysis of synaptic compartments obtained from hippocampo-septal regions. Our findings revealed that DNs were formed due to synaptic loss at the axon terminals caused by the accumulation of extracellular vesicle (EV). Abnormal EV-mediated transport and exocytosis were identified in association with primary cilia, indicating their involvement in the accumulation of EVs at presynaptic terminals. To further address the regulation of DNs by primary cilia, we conducted knockdown of the Ift88 gene in hippocampal neurons, which impaired EV-mediated secretion of Aß and promoted accumulation of axonal spheroids. Using single-cell RNA sequencing, we identified the septal projecting hippocampal somatostatin neurons (SOM) as selectively vulnerable to Aß with primary cilia dysfunction and vesicle accumulation. Our study suggests that DNs in AD are initiated by the ectopic accumulation of EVs at the neuronal axon terminals, which is affected by neuronal primary cilia.


Assuntos
Doença de Alzheimer , Vesículas Extracelulares , Animais , Camundongos , Peptídeos beta-Amiloides , Cílios , Proteômica , Axônios , Hipocampo
7.
J Am Coll Health ; : 1-8, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37437187

RESUMO

OBJECTIVE: To develop an online discrete choice experiment (DCE) to elicit preferences for the format and content of tobacco treatment and determine the feasibility of the survey in face-to-face online interviews among college students. PARTICIPANTS: A convenience sample of 28 college students. METHODS: A pilot online DCE survey with sixteen choice sets was developed. The feasibility was assessed by: 1) ease of reading the survey descriptions, 2) ease of completing the DCE survey, and 3) appropriateness of the number of choice sets. Think-aloud data were analyzed to understand decision-making processes. RESULTS: All participants completed the DCE survey and reported that it was very easy to read and complete and that the number of sixteen choice sets was appropriate. Such results support the feasibility of our online DCE survey. Five decision-making strategies were identified. CONCLUSIONS: An online DCE survey administered during online interviews may replace in-person interviews for college students.

8.
Cell Death Discov ; 9(1): 237, 2023 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-37422450

RESUMO

Triple-negative breast cancer (TNBC) is the most lethal form of breast cancer. TNBC patients have higher rates of metastasis and restricted therapy options. Although chemotherapy is the conventional treatment for TNBC, the frequent occurrence of chemoresistance significantly lowers the efficacy of treatment. Here, we demonstrated that ELK3, an oncogenic transcriptional repressor that is highly expressed in TNBC, determined the chemosensitivity of two representative TNBC cell lines (MDA-MB231 and Hs578T) to cisplatin (CDDP) by regulating mitochondrial dynamics. We observed that the knockdown of ELK3 in MDA-MB231 and Hs578T rendered these cell lines more susceptible to the effects of CDDP. We further demonstrated that the chemosensitivity of TNBC cells was caused by the CDDP-mediated acceleration of mitochondrial fission, excessive mitochondrial reactive oxygen species production, and subsequent DNA damage. In addition, we identified DNM1L, a gene encoding the dynamin-related protein 1 (a major regulator of mitochondrial fission), as a direct downstream target of ELK3. Based on these results, we propose that the suppression of ELK3 expression could be used as a potential therapeutic strategy for overcoming the chemoresistance or inducing the chemosensitivity of TNBC.

9.
Int J Mol Sci ; 24(11)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37298083

RESUMO

We investigated the mechanism of signal transduction using inactivating (R476H) and activating (D576G) mutants of luteinizing hormone receptor (LHR) of eel at the conserved regions of intracellular loops II and III, respectively, naturally occurring in mammalian LHR. The expression of D576G and R476H mutants was approximately 58% and 59%, respectively, on the cell surface compared to those of eel LHR-wild type (wt). In eel LHR-wt, cAMP production increased upon agonist stimulation. Cells expressing eel LHR-D576G, a highly conserved aspartic acid residue, exhibited a 5.8-fold increase in basal cAMP response; however, the maximal cAMP response by high-agonist stimulation was approximately 0.62-fold. Mutation of a highly conserved arginine residue in the second intracellular loop of eel LHR (LHR-R476H) completely impaired the cAMP response. The rate of loss in cell-surface expression of eel LHR-wt and D576G mutant was similar to the agonist recombinant (rec)-eel LH after 30 min. However, the mutants presented rates of loss higher than eel LHR-wt did upon rec-eCG treatment. Therefore, the activating mutant constitutively induced cAMP signaling. The inactivating mutation resulted in the loss of LHR expression on the cell surface and no cAMP signaling. These data provide valuable information regarding the structure-function relationship of LHR-LH complexes.


Assuntos
AMP Cíclico , Receptores do LH , Animais , Receptores do LH/metabolismo , AMP Cíclico/metabolismo , Mutação , Transdução de Sinais , Enguias/genética , Enguias/metabolismo , Gonadotropina Coriônica/metabolismo , Mamíferos/metabolismo
11.
Cell Commun Signal ; 21(1): 107, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37161542

RESUMO

BACKGROUND: Ex vivo cultivation is a promising strategy for increasing the number of NK cells and enhancing their antitumor activity prior to clinical application. Recent studies show that stimulation with 25KDa branched polyethylenimine (25KbPEI) generates NK cells with enhanced antitumor activity. To better understand how 25KbPEI primes NK cells, we explored the mechanism underlying increase in production of IFN-γ. METHODS: Chemical priming was performed on NK-92MI cells by incubating them with 5 µg/ml of 25KbPEI. The production of IFN-γ was evaluated by RT-qPCR, ELISA, and Flow cytometry. By evaluating the effect of pharmacological inhibition of ERK/mTOR-eIF4E signaling pathways on IFN-γ translation, the function of these signaling pathways in IFN-γ translation was examined. To comprehend the level of 25KbPEI activity on immune-related components in NK cells, RNA sequencing and proteomics analyses were conducted. RESULTS: 25KbPEI enhances the production of IFN-γ by NK cells without transcriptional activation. Activation of ERK and mTOR signaling pathways was found to be associated with 25KbPEI-mediated calcium influx in NK cells. The activation of ERK/mTOR signaling was linked to the phosphorylation of 4E-BP1, which resulted in the activation of translation initiation complex and subsequent IFN-γ translation. Analysis of RNA sequencing and proteomics data revealed that the activity of 25KbPEI to improve translation efficiency in NK cells could be extended to additional immune-related molecules. CONCLUSIONS: This study provides substantial insight into the process by which 25KbPEI primes NK cells. Our data demonstrated that the 25KbPEI mediated activation of ERK/mTOR signaling and subsequent stimulation of eIF4E is the primary mechanism by which the chemical stimulates translation of IFN-γ in NK cells. Video abstract.


Assuntos
Interferon gama , Polietilenoimina , Fator de Iniciação 4E em Eucariotos , Células Matadoras Naturais , Cálcio
12.
Exp Mol Med ; 55(5): 965-973, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37121973

RESUMO

Insulin and insulin-like growth factor 1 (IGF-1) signaling regulate cellular growth and glucose metabolism in the myocardium. However, their physiological role in the cells of the cardiac conduction system has never been explored. Therefore, we sought to determine the spatiotemporal function of insulin/IGF-1 receptors in the sinoatrial node (SAN). We generated cardiac conduction cell-specific inducible IGF-1 receptor (IGF-1R) knockout (KO) (CSIGF1RKO), insulin receptor (IR) KO (CSIRKO), and IR/IGF-1R double-KO (CSDIRKO) mice and evaluated their phenotypes. Telemetric electrocardiography revealed regular sinus rhythm in CSIGF1RKO mice, indicating that IGF-1R is dispensable for normal pacemaking. In contrast, CSIRKO and CSDIRKO mice exhibited profound sinus bradycardia. CSDIRKO mice showed typical sinus node dysfunction characterized by junctional rhythm and sinus pauses on electrocardiography. Interestingly, the lack of an insulin receptor in the SAN cells of CSIRKO and CSDIRKO mice caused sinus nodal fibrosis. Mechanistically, hyperpolarization-activated cyclic nucleotide-gated channel 4 (HCN4) protein expression significantly decreased in the CSIRKO and CSDIRKO mice relative to the controls. A patch-clamp study of the SAN cells of CSIRKO mice revealed a significant decrease in the funny current, which is responsible for spontaneous diastolic depolarization in the SAN. This result suggested that insulin receptor loss reduces the heart rate via downregulation of the HCN4 channel. Additionally, HCN1 expression was decreased in CSDIRKO mice, explaining their sinus node dysfunction. Our results reveal a previously unrecognized role of insulin/IGF-1 signaling in sinus node structural maintenance and pacemaker function.


Assuntos
Síndrome do Nó Sinusal , Nó Sinoatrial , Camundongos , Animais , Nó Sinoatrial/metabolismo , Síndrome do Nó Sinusal/metabolismo , Receptor de Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Insulina/metabolismo
13.
Sci Rep ; 13(1): 4456, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36932120

RESUMO

With advancement of technology, requirements for light-emitting devices are increasing. Various types of packaging technologies have been suggested to improve the performance of light-emitting diode (LED). Among them, phosphor in glass (PiG) is attracting attention due to its manufactural facility and easily tunable characteristics. As PiG draws increasing attention, research on glass materials is also being actively conducted. However, studies about glass in the field of phosphor are mainly conducted on fabrication. Only a few studies about recycling have been reported. Thus, the objective of this study was to recycle waste glass discarded in other fields due to breakage and failure and use it to fabricate phosphor in glass. Cylindrical waste glass was pulverized into powder with an average size of 12 µm, mixed with a phosphor and sintered to be reborn as a phosphor in glass to broaden the recycling route for waste glass.

14.
Oncoimmunology ; 12(1): 2190671, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36950218

RESUMO

Triple-negative breast cancer (TNBC) is the most challenging subtype of breast cancer because of its aggressive behavior and the limited therapeutic strategies available. In the last decade, immunotherapy has become a promising treatment to prolong survival in advanced solid cancers including TNBC. However, the efficacy of immunotherapy in solid cancers remains limited because solid tumors contain few tumor-infiltrating lymphocytes. Here, we show that targeting an ETS transcription factor ELK3 (ELK3) recruits immune cells including natural killer (NK) cells into tumors via the chemotactic activity of chemokine. ELK3 depletion increases CXCL16 expression level and promotes NK cell cytotoxicity through CXCL16-mediated NK cell recruitment in TNBC. In silico analysis showed that ELK3 is negatively correlated with CXCL16 expression in breast cancer patient samples. Low expression of ELK3 and high expression of CXCL16 were associated with a better prognosis. Low expression of ELK3 and high expression of CXCL16 were associated with increased expression of NK cell-related genes. Our findings demonstrate that the ELK3-CXCL16 axis modulates NK cell recruitment to increase NK cell cytotoxicity, suggesting that targeting the ELK3 gene could be an adjuvant strategy for increasing the efficacy of immunotherapy in TNBC.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Linhagem Celular Tumoral , Células Matadoras Naturais/metabolismo , Imunoterapia , Proteínas Proto-Oncogênicas c-ets/genética , Proteínas Proto-Oncogênicas c-ets/metabolismo , Quimiocina CXCL16/genética , Quimiocina CXCL16/metabolismo
15.
PLoS One ; 18(2): e0279627, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36827385

RESUMO

Whole-plant regeneration via plant tissue culture is a complex process regulated by several genetic and environmental conditions in plant cell cultures. Recently, epigenetic regulation has been reported to play an important role in plant cell differentiation and establishment of pluripotency. Herein, we tested the effects of chemicals, which interfere with epigenetic regulation, on the plant regeneration from mesophyll protoplasts of lettuce. The used chemicals were histone deacetylase inhibitors trichostatin A (TSA) and sodium butyrate (NaB), and the DNA methyltransferase inhibitor azacytidine (Aza). All three chemicals increased cell division, micro-callus formation and callus proliferation in lettuce protoplasts. Cell division increased by more than 20% with an optimal treatment of the three chemicals. In addition, substantial increase in the callus proliferation rates was observed. In addition, TSA enhances cell division and adventitious shoot formation in the protoplast culture of Nicotiana benthamiana. The regenerated tobacco plants from TSA-treated protoplasts did not show morphological changes similar to the control. TSA increased histone H3 acetylation levels and affected the expression of CDK, CYCD3-1, and WUS in tobacco protoplasts. Thus, we investigated the effect of TSA, NaB, and Aza on Lactuca sativa L. protoplasts and the effect of TSA on cell division and callus formation in Nicotiana benthamiana protoplasts, which facilitates plant regeneration from mesophyll protoplasts. Furthermore, these chemicals can be directly applied as media additives for efficient plant regeneration and crop improvement in various plant species.


Assuntos
Azacitidina , Nicotiana , Azacitidina/farmacologia , Nicotiana/fisiologia , Lactuca , Epigênese Genética , Protoplastos , Divisão Celular , Inibidores de Histona Desacetilases/farmacologia
16.
Behav Med ; 49(3): 312-319, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35465849

RESUMO

The adverse effects of multiple health risk factors have been well-documented; however, still understudied are the effects of early smoking in the context of multiple health risk factors. This study aimed to examine the role of early smoking initiation in relation to several health risk factors, including heavy drinking, physical inactivity, and obesity in later life among ever smokers in the USA. The National Health Interview Survey (NHIS) data from 2006 through 2018 were analyzed. The primary dependent variables were presence of three other risk factors: heavy drinking, physical inactivity, and obesity. The independent variable was the age of smoking initiation. Logit regression models were constructed to evaluate the association between smoking initiation and multiple health risk factors. All analyses were done in 2022. Among US adult smokers, 18.2% started smoking before age 15 (early initiators), 55.9% at ages 15-18 (middle initiators), and 25.9% at age 20 or later (late initiators). Compared to late smoking initiators, the odds of engaging in additional health risk factors increased by 37.3% among early initiators (OR = 1.373, 95% CI = 1.316, 1.432) and 7.7% among middle initiators (OR = 1.077, 95% CI= 1.041, 1.116). Additionally, current smoking was associated with higher odds (OR = 1.369, 95% CI = 1.322, 1.417) of having additional health risk factors compared to former smoking, with one exception: current smokers had lower odds of obesity (OR = 0.566, 95% CI = 0.537, 0.597). Tobacco control programs to prevent adolescents from initiating smoking may have the potential to prevent other health risk factors in adulthood.

17.
Oncol Res ; 32(1): 127-138, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38188675

RESUMO

Purpose: Cancer cell metastasis is a multistep process, and the mechanism underlying extravasation remains unclear. ELK3 is a transcription factor that plays a crucial role in regulating various cellular processes, including cancer metastasis. Based on the finding that ELK3 promotes the metastasis of triple-negative breast cancer (TNBC), we investigated whether ELK3 regulates the extravasation of TNBC by forming the ELK3-ID4 axis. ID4 functions as a transcriptional regulator that interacts with other transcription factors, inhibiting their activity and subsequently influencing various biological processes associated with cell differentiation, survival, growth, and metastasis. Methods: We assessed the correlation between the expression of ELK3 and that of ID4 in TNBCs using bioinformatics analyses, QRT-PCR, western blot analysis, luciferase reporter assays, and chromatin immunoprecipitation. Migration, adhesion, invasion, and lung metastasis assays were employed to determine whether the ELK3-ID4 axis regulates the metastatic features of TNBC. Results: We found that ELK3 binds directly to a binding motif close to the ID4 promoter to repress promoter activity. The expression of E-cadherin in TNBC was regulated by the ELK3-ID4 axis. In vitro and in vivo analyses showed that inhibiting ID4 expression in ELK3-knockdown MDA-MB-231 (ELK3KD) cells restored the ability to extravasate and metastasize. Conclusion: The results indicate that the ELK3 regulates ID4 promoter activity, and that the ELK3-ID4 axis regulates the metastatic characteristics of TNBC cells. Additionally, the data suggest that the ELK3-ID4 axis regulates metastasis of TNBCs by modulating expression of E-cadherin.


Assuntos
Proteínas Inibidoras de Diferenciação , Proteínas Proto-Oncogênicas c-ets , Neoplasias de Mama Triplo Negativas , Humanos , Caderinas/genética , Diferenciação Celular , Biologia Computacional , Proteínas Inibidoras de Diferenciação/genética , Neoplasias Pulmonares/secundário , Neoplasias de Mama Triplo Negativas/genética , Proteínas Proto-Oncogênicas c-ets/genética
18.
J Health Care Poor Underserved ; 34(4): 1398-1413, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38661763

RESUMO

Food insecurity and smoking commonly co-occur in underserved populations, exacerbating health disparities. This study assesses smoking and its associations with mental health and health risk behaviors among residents of Flint, Michigan in the early phase of COVID lockdowns. The survey captured smoking status, mental health indicators, and health risk behaviors among 106 who had financial needs and limited mobility and received community nutritional services. Comparisons by demographics showed that those who lived alone, used marijuana, and had frequent alcohol drinking tended to smoke more than their counterparts. Results from logistic regression showed that those with high levels of stress, marijuana use, and alcohol consumption were more likely to smoke. Living alone was associated with smoking and health risk behaviors. This research suggests the need for smoking prevention and community health practices addressing stress, health risk behaviors, and circumstances that might drive the association with living alone such as loneliness.


Assuntos
COVID-19 , Comportamentos de Risco à Saúde , Fumar , Estresse Psicológico , Humanos , COVID-19/epidemiologia , Michigan/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Fumar/epidemiologia , Adulto , Estresse Psicológico/epidemiologia , Idoso , Consumo de Bebidas Alcoólicas/epidemiologia
19.
Micromachines (Basel) ; 13(11)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36422446

RESUMO

The aim of this study was to investigate properties of ceramic phosphors fabricated using nano Lu3Al5O12:Ce3+ phosphors produced with a sol-gel-combustion method. These nano Lu3Al5O12:Ce3+ phosphors had a size of about 200 nm, leading to high density when fabricated as a ceramic phosphor. We manufactured ceramic phosphors through vacuum sintering. Alumina powder was added to improve properties. We mounted the manufactured ceramic phosphor in a high-power laser beam projector and drove it to determine its optical performance. Ceramic phosphor manufactured according to our route will have a significant impact on the laser-driven lighting industry.

20.
Sci Rep ; 12(1): 20477, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36443320

RESUMO

This study investigates the characteristics of a ceramic phosphor (CP) for the converter of a high-power laser diode-based automobile headlamp synthesized by high-frequency induction heated press (HFP) sintering. The CP prepared by an HFP method exhibits remarkable optical properties that are comparable to spark plasma sintering. The effects of post-treatment process for controlling residual pores, as well as sintering temperature, sintering pressure and heating rate for optimization of the HFP sintering method, were studied. The HFP sintering process can be widely used in ceramics and lighting fields because it is designed relatively low cost compared to other techniques and exhibits excellent productivity.

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