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Fiber-integrated, submersible-qualified, core-pumped, multicore EDFAs are indispensable for space-division-multiplexing envisioned for the next generation of submarine communication lines. Here we demonstrate a fully packaged, 63-dB counter-propagating crosstalk, and 70-dB-return-loss four-core pump-signal-combiner. This enables core-pumping of a four-core EDFA.
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We have designed, developed, and deployed the world's first ultra-dense space division-multiplexing multicore fiber link in a conduit of a metro network. In a 10-mm-diameter fiber optic-cable, 288 4-core multicore fibers are arranged in 24 200-µm spiderweb collapsible ribbons. The multicore fibers are fusion-spliced to 576 fanout devices which provide conventional single-core interfaces at patch panels at both ends of the link.
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We propose a novel strategy to search for new physics in timing spectra at low-energy neutrino experiments using a pulsed beam, envisioning the situation in which a new particle comes from the decay of its heavier partner with a finite particle width. The timing distribution of events induced by the dark matter (DM) candidate particle scattering at the detector may populate in a relatively narrow range, forming a "resonancelike" shape. Because of this structural feature, the signal may be isolated from the backgrounds, in particular when the backgrounds are uniformly distributed in energy and time. For proof of the principle, we investigate the discovery potential for DM from the decay of a dark photon in the ongoing COHERENT experiment and show the exciting prospects for exploring the associated parameter space with this experiment. We analyze the existing CsI detector data with a timing cut and an energy cut, and we find, for the first time, an excess in the timing distribution that can be explained by such DM. We compare the sensitivity to the kinetic mixing parameter (ε) for current and future COHERENT experiments with the projected limits from LDMX and DUNE.
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Schwann cells (SCs), the primary glia in the peripheral nervous system (PNS), display remarkable plasticity in that fully mature SCs undergo dedifferentiation and convert to repair SCs upon nerve injury. Dedifferentiated SCs provide essential support for PNS regeneration by producing signals that enhance the survival and axon regrowth of damaged neurons, but the identities of neurotrophic factors remain incompletely understood. Here we show that SCs express and secrete progranulin (PGRN), depending on the differentiation status of SCs. PGRN expression and secretion markedly increased as primary SCs underwent dedifferentiation, while PGRN secretion was prevented by administration of cAMP, which induced SC differentiation. We also found that sciatic nerve injury, a physiological trigger of SC dedifferentiation, induced PGRN expression in SCs in vivo. These results suggest that dedifferentiated SCs express and secrete PGRN that functions as a paracrine factor to support the survival and axon growth of neighboring neurons after injury.
Assuntos
Axônios/patologia , Proliferação de Células/efeitos dos fármacos , Neurônios Motores/patologia , Progranulinas/metabolismo , Células de Schwann/metabolismo , Neuropatia Ciática/patologia , Animais , Axônios/efeitos dos fármacos , Bucladesina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Meios de Cultivo Condicionados/farmacologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Fluoresceínas/metabolismo , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos ICR , Neurônios Motores/efeitos dos fármacos , Progranulinas/farmacologia , RNA Mensageiro/metabolismo , Células de Schwann/química , Medula Espinal/citologiaRESUMO
Axonal regeneration and remyelination of peripheral motor neurons (MNs) are critical for restoring neuromuscular motor function after injury or peripheral neuropathy. We examined whether optogenetically mediated light stimulation (OMLS) could enhance the axon outgrowth and myelination of MNs using three-dimensional motor neuron-Schwann cell (MN-SC) coculture on a microfluidic biochip. The biochip was designed to allow SCs to interact with the axons of MNs, while preventing direct contact between SCs and the cell bodies of MNs. Following coculture with SCs on the microfluidic biochip, MNs were transfected with a light-sensitive channelrhodopsin gene. Transfected MNs subjected to repeated light stimulation (20 Hz, 1 hr) produced significantly longer axons than nontransfected MNs. OMLS of MNs greatly increased the number of myelin basic protein (MBP)-expressing SCs, promoting the initiation of myelination of MNs. Ultrastructurally, OMLS of MNs markedly enhanced the thickness of the compact myelin sheath around the MN axons such that the average thickness was closer to that of the theoretical estimates in vivo. Thus, the MN-SC coculture model on a microfluidic biochip augmented by OMLS of MNs is a feasible platform for studying the relationship of neuronal activity with regrowth and remyelination.
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Axônios/metabolismo , Dispositivos Lab-On-A-Chip , Neurônios Motores/metabolismo , Optogenética , Células de Schwann/metabolismo , Animais , Técnicas de Cocultura , Camundongos , Neurônios Motores/citologia , Células de Schwann/citologiaRESUMO
Cell sheet engineering has evolved rapidly in recent years as a new approach for cell-based therapy. Cell sheet harvest technology is important for producing viable, transplantable cell sheets and applying them to tissue engineering. To date, most cell sheet studies use thermo-responsive systems to detach cell sheets. However, other approaches have been reported. This review provides the progress in cell sheet detachment techniques, particularly reactive oxygen species (ROS)-responsive strategies. Therefore, we present a comprehensive introduction to ROS, their application in regenerative medicine, and considerations on how to use ROS in cell detachment. The review also discusses current limitations and challenges for clarifying the mechanism of the ROS-responsive cell sheet detachment.
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Espécies Reativas de Oxigênio/metabolismo , Engenharia Tecidual/métodos , Animais , HumanosRESUMO
Systemic injection of a photosensitizer is a general method in photodynamic therapy, but it has complications due to the unintended systemic distribution and remnants of photosensitizers. This study focused on the possibility of suppressing luminal proliferative cells by excessive reactive oxygen species from locally delivered photosensitizer with biocompatible polyurethane, instead of the systemic injection method. We used human bladder cancer cells, hematoporphyrin as the photosensitizer, and polyurethane film as the photosensitizer-delivering container. The light source was a self-made LED (510 nm, 5 mW cm-2) system. The cancer cells were cultured on different doses of hematoporphyrin-containing polyurethane film and irradiated with LED for 15 minutes and 30 minutes each. After irradiating with LED and incubating for 24 hours, cell viability analysis, cell cycle analysis, apoptosis assay, intracellular and extracellular ROS generation study and western blot were performed. The cancer cell suppression effects of different concentrations of the locally delivered hematoporphyrin with PDT were compared. Apoptosis dominant cancer cell suppressions were shown to be hematoporphyrin dose-dependent. However, after irradiation, intracellular ROS amounts were similar in all the groups having different doses of hematoporphyrin, but these values were definitely higher than those in the control group. Excessive extracellular ROS from the intended, locally delivered photosensitizer for photodynamic treatment application had an inhibitory effect on luminal proliferative cancer cells. This method can be another possibility for PDT application on contactable or attachable lesions.
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Antineoplásicos/farmacologia , Sistemas de Liberação de Medicamentos , Hematoporfirinas/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Poliuretanos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Neoplasias da Bexiga Urinária/tratamento farmacológico , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Hematoporfirinas/química , Humanos , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Poliuretanos/química , Espécies Reativas de Oxigênio/análise , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Raios Ultravioleta , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologiaRESUMO
In recent tissue engineering applications, the advance of biomaterials has focused on the devising of biomimetic materials that are directing new tissue formation and capable of causing specific cellular responses. These advances can be controlled by modifying the devising parameters of the materials. The biomimetic materials potentially mimic many roles of ECM in tissues. For the homogeneous distribution and biocompatibility of scaffolds by cell migration with biomimetic materials, cell migration is studied because it has a important role in physiological phenomenon and in pathologies; cancer metastasis, immune response or embryonic development. This review discusses the migration of cells with biomimetic materials for tissue engineering. It is also summarized that the recent advances of cell migration with biomimetic materials in 2-D and 3-D for tissue engineering.
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Materiais Biomiméticos , Movimento Celular , Matriz Extracelular , Engenharia Tecidual , Materiais Biocompatíveis , Humanos , Alicerces TeciduaisRESUMO
We propose a novel dark matter (DM) detection strategy for models with a nonminimal dark sector. The main ingredients in the underlying DM scenario are a boosted DM particle and a heavier dark sector state. The relativistic DM impinged on target material scatters off inelastically to the heavier state, which subsequently decays into DM along with lighter states including visible (standard model) particles. The expected signal event, therefore, accompanies a visible signature by the secondary cascade process associated with a recoiling of the target particle, differing from the typical neutrino signal not involving the secondary signature. We then discuss various kinematic features followed by DM detection prospects at large-volume neutrino detectors with a model framework where a dark gauge boson is the mediator between the standard model particles and DM.
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PURPOSE: Cranioplasty for recovering skull defects carries the risk for a number of complications. Various materials are used, including autologous bone graft, metallic materials, and non-metallic materials, each of which has advantages and disadvantages. If the use of autologous bone is not feasible, those artificial materials also have constraints in the case of complex anatomy and/or irregular defects. MATERIAL AND METHODS: This study used metal 3D-printing technology to overcome these existing drawbacks and analyze the clinical and mechanical performance requirements. To find an optimal structure that satisfied the structural and mechanical stability requirements, we evaluated biomechanical stability using finite element analysis (FEA) and mechanical testing. To ensure clinical applicability, the model was subjected to histological evaluation. Each specimen was implanted in the femur of a rabbit and was evaluated using histological measurements and push-out test. RESULTS AND CONCLUSION: We believe that our data will provide the basis for future applications of a variety of unit structures and further clinical trials and research, as well as the direction for the study of other patient-specific implants.
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Impressão Tridimensional , Crânio , Engenharia Tecidual , Alicerces Teciduais , Animais , Fenômenos Biomecânicos , Análise de Elementos Finitos , Humanos , Próteses e Implantes , Coelhos , Procedimentos de Cirurgia PlásticaRESUMO
Emerging studies have revealed the involvement of high-mobility group box 1 (HMGB1) in systemic fibrotic diseases, yet its role in the cutaneous scarring process has not yet been investigated. We hypothesized that HMGB1 may promote fibroblast activity to cause abnormal cutaneous scarring. In vitro wound healing assay with normal and keloid fibroblasts demonstrated that HMGB1 administration promoted the migration of both fibroblasts with increased speed and a greater traveling distance. Treatment of the HMGB1 inhibitor glycyrrhizic acid (GA) showed an opposing effect on both activities. To analyze the downstream mechanism, the protein levels of extracellular signal-regulated kinase (ERK) 1/2, protein kinase B (AKT), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) were measured by western blot analysis. HMGB1 increased the expression levels of ERK1/2, AKT, and NF-κB compared to the control, which was suppressed by GA. HMGB1 promoted both normal and keloid fibroblasts migration to a degree equivalent to that achieved with TGF-ß. We concluded that HMGB1 activates fibroblasts via the receptor for advanced glycation end product (RAGE)-mitogen-activated protein kinases (MAPK) and NF-κB interaction signaling pathways. Further knowledge of the relationship of HMGB1 with skin fibrosis may lead to a promising clinical approach to manage abnormal scarring.
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Antígenos de Neoplasias/genética , Fibroblastos/metabolismo , Proteína HMGB1/genética , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/genética , NF-kappa B/genética , Proteínas Proto-Oncogênicas c-akt/genética , Anti-Inflamatórios/farmacologia , Antígenos de Neoplasias/metabolismo , Bioensaio , Movimento Celular/efeitos dos fármacos , Rastreamento de Células , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Regulação da Expressão Gênica , Ácido Glicirrízico/farmacologia , Proteína HMGB1/antagonistas & inibidores , Proteína HMGB1/metabolismo , Humanos , Queloide/genética , Queloide/metabolismo , Queloide/patologia , Queloide/prevenção & controle , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Cicatrização/efeitos dos fármacosRESUMO
Kim, T-G, Kim, E-K, and Park, J-C. Immediate effects of sports taping applied on the lead knee of low- and high-handicapped golfers during golf swing. J Strength Cond Res 31(4): 981-989, 2017-Elite golf athletes suffer from various musculoskeletal injuries due to repeated golf swings. Repetitive varus moment during golf swing has been suggested as a possible cause of injuries to the lead knee. The aim of this study was to objectively and quantitatively evaluate the immediate effects of sports taping on the lead knee of elite golfers to restrict varus moment. Thirty-one elite golfers were assigned to the low- (LHG, n = 15) or high-handicapped group (HHG, n = 16). Using 3-dimensional motion analysis, the lead knee position on the frontal plane with and without rigid taping (RT), elastic taping (ET), and placebo taping was identified in 4 separate phases by the 5 events of golf swing as follows: the peak of the backswing (E1), parallel to the ground during downswing (E2), ball impact (E3), parallel to the ground during follow-through (E4), and finish (E5). The LHG when using a driver club had decreased movement toward knee varus with RT and ET than that without it from E1 to E2 (p = 0.001). The LHG when using a 5-iron club decreased movement toward knee varus with RT than that without it from E1 to E2 (p = 0.006) and from E2 to E3 (p = 0.019). The HHG when using a driver club had decreased movement toward knee varus with RT from E1 to E2 (p = 0.014). Sports taping may be helpful for elite golfers in terms of reducing varus moment of the lead knee during the downswing and be useful for the development of preventive strategies for golf-related knee injuries.
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Atletas , Fita Atlética , Golfe/fisiologia , Articulação do Joelho/fisiologia , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Traumatismos do Joelho/prevenção & controle , Masculino , Movimento , Adulto JovemRESUMO
The aims of this study were to investigate the ankle position, the changes and persistence of ankle kinematics after neuromuscular training in athletes with chronic ankle instability (CAI). A total of 21 national women's field hockey players participated (CAI = 12, control = 9). Ankle position at heel strike (HS), midstance (MS), and toe touch (TT) in the frontal plane during walking, running and landing were measured using 3D motion analysis. A 6-week neuromuscular training program was undertaken by the CAI group. Measurements of kinematic data for both groups were measured at baseline and the changes in kinematic data for CAI group were measured at 6 and 24 weeks. The kinematic data at HS during walking and running demonstrated that the magnitude of the eversion in the CAI group (-5.00° and -4.21°) was less than in the control group (-13.45°and -9.62°). The kinematic data at MS also exhibited less ankle eversion in the CAI group (-9.36° and -8.18°) than in the control group (-18.52° and -15.88°). Ankle positions at TT during landing were comparable between groups. Following the 6-week training, the CAI participants demonstrated a less everted ankle at HS during walking and running (-1.77° and -1.76°) compared to the previous positions. They also showed less ankle eversion at MS (-5.14° and -4.19°). Ankle orientation at TT changed significantly to an inverted ankle position (from -0.26° to 4.11°). The ankle kinematics were restored back to the previous positions at 24 weeks except for landing. It appeared that athletes with unstable ankle had a relatively inverted ankle position, and that 6-week neuromuscular training had an immediate effect on changing ankle orientation toward a less everted direction. The changed ankle kinematics seemed to persist during landing but not during walking and running.
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The interplay between bone-forming osteoblasts and bone-resorbing osteoclasts is essential for balanced bone remodeling. In this study, we evaluate the ability of ethyl-2, 5-dihyrdoxybenzoate (E-2, 5-DHB) to affect both osteoblast and osteoclast differentiation for bone regeneration. Osteogenic differentiation of human mesenchymal stem cells (hMSCs) was quantified by measuring alkaline phosphatase (ALP) activity and calcium deposition. To evaluate osteoclast differentiation, we investigated the effect of E-2, 5-DHB on RANKL-activated osteoclastogenesis in RAW 264.7 cells. E-2, 5-DHB enhanced ALP activity and inhibited RAW 264.7 cell osteoclastogenesis in vitro. To assess the in vivo activity of E-2, 5-DHB, hMSCs were delivered subcutaneosuly alone or in combination with E-2, 5-DHB in an alginate gel into the backs of nude-mice. Histological and immunohistochemical evaluation showed significantly higher calcium deposition in the E-2, 5-DHB group. Osteocalcin (OCN) was highly expressed in cells implanted in the gels containing E-2, 5-DHB. Our results suggest that E-2, 5-DHB can effectively enhance osteoblast differentiation and inhibit osteoclast differentiation both in vitro and in vivo. Understanding the dual function of E-2, 5-DHB on osteoblast and osteoclast differentiation will aid in future development of E-2, 5-DHB as a material for bone tissue engineering.
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Hidroxibenzoatos/administração & dosagem , Células-Tronco Mesenquimais/citologia , Osteoblastos/citologia , Osteoclastos/citologia , Osteogênese/fisiologia , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Relação Dose-Resposta a Droga , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/fisiologia , Osteogênese/efeitos dos fármacos , Células RAW 264.7RESUMO
We discuss nonstandard interpretations of the 750 GeV diphoton excess recently reported by the ATLAS and CMS Collaborations which do not involve a new, relatively broad resonance with a mass near 750 GeV. Instead, we consider the sequential cascade decay of a much heavier, possibly quite narrow, resonance into two photons along with one or more additional particles. The resulting diphoton invariant mass signal is generically rather broad, as suggested by the data. We examine three specific event topologies-the "antler," the "sandwich," and the two-step cascade decay-and show that they all can provide a good fit to the observed published data. In each case, we delineate the preferred mass parameter space selected by the best fit. In spite of the presence of extra particles in the final state, the measured diphoton p_{T} spectrum is moderate due to its anticorrelation with the diphoton invariant mass. We comment on the future prospects of discriminating with higher statistics between our scenarios, as well as from more conventional interpretations.
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Directional cell migration requires cell polarization. The reorganization of the Golgi apparatus is an important phenomenon in the polarization and migration of many types of cells. Direct current electric fields (dc (EF) induced directional cell migration in a wide variety of cells. Here nHDFs migrated toward cathode under 1 V/cm dc EF, however 1 µM of brefeldin A (BFA) inhibited the dc EF induced directional migration. BFA (1 µM) did not cause the complete Golgi dispersal for 2 h. When the Golgi polarization maintained their direction of polarity, the direction of cell migration also kept toward the same direction of the Golgi polarization even though the dc EF was reversed. In this study, the importance of the Golgi polarization in the directional migration of nHDf under dc EF was identified.
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Movimento Celular , Eletricidade , Complexo de Golgi/fisiologia , Pele/citologia , Brefeldina A/farmacologia , Fibroblastos/citologia , Humanos , Recém-Nascido , Microscopia de FluorescênciaRESUMO
The infiltration of the cells into the scaffolds is important phenomenon to give them good biocompatibility and even biodegradability. Fluid shear stress is one of the candidates for the infiltration of cells into scaffolds. Here we investigated the directional migration of human mesenchymal stem cells and infiltration into PLGA scaffold by fluid shear stress. The human mesenchymal stem cells showed directional migrations following the direction of the flow (8, 16 dyne/cm(2)). In the scaffold models, the fluid shear stress (8 dyne/cm(2)) enhanced the infiltration of cells but did not influence on the infiltration of Poly(lactic-co-glycolic acid) particles.
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Ácido Láctico/química , Células-Tronco Mesenquimais/fisiologia , Ácido Poliglicólico/química , Alicerces Teciduais/química , Materiais Biocompatíveis/química , Movimento Celular , Células Cultivadas , Humanos , Hidrodinâmica , Células-Tronco Mesenquimais/citologia , Microscopia Eletrônica de Varredura , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Engenharia Tecidual/instrumentaçãoRESUMO
Osteoprogenitor cells play a significant role in the growth or repair of bones, and have great potential as cell sources for regenerative medicine and bone tissue engineering, but control of their specific differentiation into bone cells remains a challenge. Graphene-based nanomaterials are attractive candidates for biomedical applications as substrates for stem cell (SC) differentiation, scaffolds in tissue engineering, and components of implant devices owing to their biocompatible, transferable and implantable properties. This study examined the enhanced osteogenic differentiation of human mesenchymal stem cells (hMSCs) by reduced graphene oxide (rGO) nanoparticles (NPs), and rGO NPs was prepared by reducing graphene oxide (GO) with a hydrazine treatment followed by annealing in argon and hydrogen. The cytotoxicity profile of each particle was examined using a water-soluble tetrazolium-8 (WST-8) assay. At different time-points, a WST-8 assay, alkaline phosphatase (ALP) activity assay and alizarin red S (ARS) staining were used to determine the effects of rGO NPs on proliferation, differentiation and mineralization, respectively. The results suggest that graphene-based materials have potential as a platform for stem cells culture and biomedical applications.
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Diferenciação Celular/efeitos dos fármacos , Grafite/química , Grafite/farmacologia , Células-Tronco Mesenquimais/metabolismo , Osteogênese/efeitos dos fármacos , Células Cultivadas , Humanos , Células-Tronco Mesenquimais/citologia , Oxirredução , Óxidos/química , Óxidos/farmacologiaRESUMO
Epigallocatechin-3-O-gallate (EGCG) is a major polyphenolic compound in green tea. It has been known that EGCG regulates the secretion of cytokines and the activation of skin cells during wound healing. In this study, various concentrations of EGCG were added to the electrospun membranes composed of poly (lactic-co-glycolic acid) (PLGA), and its healing effects on full-thickness wounds created in nude mice were investigated. The electrospun membranes containing 5 wt% EGCG (5EGCG/PLGA membrane) exhibited cytotoxicity in human dermal fibroblasts (HDFs) as HDF morphologies were transformed on them. In the animal study, cell infiltration of mice treated with electrospun membranes containing 1 wt% EGCG (1EGCG/PLGA membrane) significantly increased after 2 weeks. The immunoreactivity of Ki-67 (re-epithelialization at the wound site) and CD 31 (formation of blood vessels) also increased in the mice treated with 1EGCG/PLGA membranes in comparison with the mice treated with PLGA membranes. These results suggest that 1EGCG/PLGA can enhance wound healing in full thickness by accelerating cell infiltration, re-epithelialization, and angiogenesis.
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Antioxidantes/uso terapêutico , Bandagens , Catequina/análogos & derivados , Ácido Láctico/química , Ácido Poliglicólico/química , Cicatrização/efeitos dos fármacos , Adulto , Animais , Antioxidantes/administração & dosagem , Catequina/administração & dosagem , Catequina/uso terapêutico , Linhagem Celular , Humanos , Masculino , Membranas Artificiais , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Copolímero de Ácido Poliláctico e Ácido PoliglicólicoRESUMO
As sports activities have recently become socio-culturally important in South Korea, the roles and functions of public sports organizations are attracting attention. In this situation, perceived organizational support is considered one of the significant variables to explain the attitudes and behaviors of employees within the organizations. Hence, the purpose of this study is to investigate the relationship between perceived organizational support of public sports organizations, work engagement, organizational citizenship behavior, and customer orientation and examine the mediating effect of work engagement. This study collected data from 248 employees working for public sports organizations, and data were analyzed with SPSS 26.0 and AMOS 26.0. The results showed the following. (1) Perceived organizational support has a significant positive effect on work engagement but does not affect organizational citizenship behavior and customer orientation. (2) Work engagement significantly positively affects organizational citizenship behavior and customer orientation. (3) Work engagement has been shown to fully mediate the relationship between perceived organizational support, organizational citizenship behavior, and customer orientation. This study suggests that public sports organizations need an efficient support strategy that can maximize employees' work engagement. For example, organizations should increase their sense of unity with employees and understand the importance of their work to strengthen perceived organizational support. Lastly, organizations need to create an environment where employees can devote themselves to and focus on their work.