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1.
Environ Pollut ; 348: 123774, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38499174

RESUMO

Industrial cities are strongly influenced by primary emissions of PM2.5 from local industries. In addition, gaseous precursors, such as sulfur oxides (SOX), nitrogen oxides (NOX), and volatile organic compounds (VOCs), emitted from industrial sources, undergo conversion into secondary inorganic and organic aerosols (SIAs and SOAs). In this study, the spatial distributions of primary and secondary PM2.5 in Ulsan, the largest industrial city in South Korea, were visualized. PM2.5 components (ions, carbons, and metals) and PM2.5 precursors (SO2, NO2, NH3, and VOCs) were measured to estimate the concentrations of secondary inorganic ions (SO42-, NO3-, and NH4+) and secondary organic aerosol formation potential (SOAFP). The spatial distributions of SIAs and SOAs were then plotted by combining atmospheric dispersion modeling, receptor modeling, and monitoring data. Spatial distribution maps of primary and secondary PM2.5 provide fundamental insights for formulating management policies in different districts of Ulsan. For instance, among the five districts in Ulsan, Nam-gu exhibited the highest levels of primary PM2.5 and secondary nitrate. Consequently, controlling both PM2.5 and NO2 emissions becomes essential in this district. The methodology developed in this study successfully identified areas with dominant contributions from both primary emissions and secondary formation. This approach can be further applied to prioritize control measures during periods of elevated PM levels in other industrial cities.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Material Particulado/análise , Cidades , Dióxido de Nitrogênio , Monitoramento Ambiental/métodos , Nitratos , Compostos Orgânicos Voláteis/análise , Aerossóis/análise , Estações do Ano
2.
Int J Mol Sci ; 24(2)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36674697

RESUMO

Anoctamin1 (ANO1), a calcium-activated chloride channel, is involved in the proliferation, migration, and invasion of various cancer cells including head and neck squamous cell carcinoma, lung cancer, and prostate cancer. Inhibition of ANO1 activity or downregulation of ANO1 expression in these cancer cells is known to exhibit anticancer effects. Resveratrol, a natural polyphenol abundant in wines, grapes, berries, soybeans, and peanuts, shows a wide variety of biological effects including anti-inflammatory, antioxidant, and anticancer activities. In this study, we investigated the effects of two stereoisomers of resveratrol on ANO1 activity and found that cis- and trans-resveratrol inhibited ANO1 activity with different potencies. Cis- and trans-resveratrol inhibited ANO1 channel activity with IC50 values of 10.6 and 102 µM, respectively, and had no significant effect on intracellular calcium signaling at 10 and 100 µM, respectively. In addition, cis-resveratrol downregulated mRNA and protein expression levels of ANO1 more potently than trans-resveratrol in PC-3 prostate cancer cells. Cis- and trans-resveratrol significantly reduced cell proliferation and cell migration in an ANO1-dependent manner, and both resveratrol isomers strongly increased caspase-3 activity, PARP cleavage, and apoptotic sub-G1 phase ratio in PC-3 cells. These results revealed that cis-resveratrol is a potent inhibitor of ANO1 and exhibits ANO1-dependent anticancer activity against human metastatic prostate cancer PC-3 cells.


Assuntos
Neoplasias de Cabeça e Pescoço , Neoplasias da Próstata , Masculino , Humanos , Resveratrol/farmacologia , Células PC-3 , Anoctamina-1/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Proteínas de Neoplasias/metabolismo
3.
Sensors (Basel) ; 21(6)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33806907

RESUMO

Authentication methods using personal identification number (PIN) and unlock patterns are widely used in smartphone user authentication. However, these authentication methods are vulnerable to shoulder-surfing attacks, and PIN authentication, in particular, is poor in terms of security because PINs are short in length with just four to six digits. A wide range of research is currently underway to examine various biometric authentication methods, for example, using the user's face, fingerprint, or iris information. However, such authentication methods provide PIN-based authentication as a type of backup authentication to prepare for when the maximum set number of authentication failures is exceeded during the authentication process such that the security of biometric authentication equates to the security of PIN-based authentication. In order to overcome this limitation, research has been conducted on keystroke dynamics-based authentication, where users are classified by analyzing their typing patterns while they are entering their PIN. As a result, a wide range of methods for improving the ability to distinguish the normal user from abnormal ones have been proposed, using the typing patterns captured during the user's PIN input. In this paper, we propose unique keypads that are assigned to and used by only normal users of smartphones to improve the user classification performance capabilities of existing keypads. The proposed keypads are formed by randomly generated numbers based on the Mersenne Twister algorithm. In an attempt to demonstrate the superior classification performance of the proposed unique keypad compared to existing keypads, all tests except for the keypad type were conducted under the same conditions in earlier work, including collection-related features and feature selection methods. Our experimental results show that when the filtering rates are 10%, 20%, 30%, 40%, and 50%, the corresponding equal error rates (EERs) for the proposed keypads are improved by 4.15%, 3.11%, 2.77%, 3.37% and 3.53% on average compared to the classification performance outcomes in earlier work.

4.
Phys Rev E ; 104(6-1): 064304, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35030955

RESUMO

Consider a multiplex network formed by two layers indicating social interactions: the first layer is a friendship network and the second layer is a network of business relations. In this duplex network each pair of individuals can be connected in different ways: they can be connected by a friendship but not connected by a business relation, they can be connected by a business relation without being friends, or they can be simultaneously friends and in a business relation. In the latter case we say that the links in different layers overlap. These three types of connections are called multilinks and the multidegree indicates the sum of multilinks of a given type that are incident to a given node. Previous opinion models on multilayer networks have mostly neglected the effect of link overlap. Here we show that link overlap can have important effects in the formation of a majority opinion. Indeed, the formation of a majority opinion can be significantly influenced by the statistical properties of multilinks, and in particular by the multidegree distribution. To quantitatively address this problem, we study a simple spin model, called the Ashkin-Teller model, including two-body and four-body interactions between nodes in different layers. Here we fully investigate the rich phase diagram of this model which includes a large variety of phase transitions. Indeed, the phase diagram or the model displays continuous, discontinuous, and hybrid phase transitions, and successive jumps of the order parameters within the Baxter phase.

5.
Phys Rev E ; 101(2-1): 022121, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32168624

RESUMO

Recently, the quantum contact process, in which branching and coagulation processes occur both coherently and incoherently, was theoretically and experimentally investigated in driven open quantum spin systems. In the semiclassical approach, the quantum coherence effect was regarded as a process in which two consecutive atoms are involved in the excitation of a neighboring atom from the inactive (ground) state to the active state (excited s-state). In this case, both second-order and first-order transitions occur. Therefore, a tricritical point exists at which the transition belongs to the tricritical directed percolation (TDP) class. On the other hand, when an atom is excited to the d-state, long-range interaction is induced. Here, to account for this long-range interaction, we extend the TDP model to one with long-range interaction in the form of ∼1/r^{d+σ} (denoted as LTDP), where r is the separation, d is the spatial dimension, and σ is a control parameter. In particular, we investigate the properties of the LTDP class below the upper critical dimension d_{c}=min(3,1.5σ). We numerically obtain a set of critical exponents in the LTDP class and determine the interval of σ for the LTDP class. Finally, we construct a diagram of universality classes in the space (d,σ).

6.
Phys Rev E ; 99(3-1): 032131, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30999423

RESUMO

We investigate a nonequilibrium phase transition in a dissipative and coherent quantum spin system using the quantum Langevin equation and mean-field theory. Recently, the quantum contact process (QCP) was theoretically investigated using the Rydberg antiblockade effect, in particular, when the Rydberg atoms were excited in s states so that their interactions were regarded as being between the nearest neighbors. However, when the atoms are excited to d states, the dipole-dipole interactions become effective, and long-range interactions must be considered. Here we consider a quantum spin model with a long-range QCP, where the branching and coagulation processes are allowed not only for the nearest-neighbor pairs but also for long-distance pairs, coherently and incoherently. Using the semiclassical approach, we show that the mean-field phase diagram of our long-range model is similar to that of the nearest-neighbor QCP, where the continuous (discontinuous) transition is found in the weak (strong) quantum regime. However, at the tricritical point, we find a new universality class, which was neither that of the QCP at the tricritical point nor that of the classical directed percolation model with long-range interactions. Implementation of the long-range QCP using interacting cold gases is discussed.

7.
Mol Neurobiol ; 56(8): 5555, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30729425

RESUMO

The original version of this article, the name of author was incorrectely presented. That is Kyungjae Won (K. Won) should be presented as Jae Won Kyung (J.W. Kyung).

8.
Mol Neurobiol ; 56(8): 5539-5554, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30637664

RESUMO

Neuropathic pain is a devastating chronic condition and effective treatments are still lacking. Carbon monoxide-releasing molecule-2 (CORM-2) as a carbon monoxide (CO) carrier, exerts potent anti-neuropathic pain effects; however, its poor water solubility and short half-life hinder its clinical utility. Therefore, the aim of this study was to investigate whether CORM-2-loaded solid lipid nanoparticles (CORM-2-SLNs) enhance the anti-allodynic and anti-hyperalgesic effects of CORM-2 in a rat chronic constriction injury (CCI) model. CORM-2-SLNs were prepared using a nanotemplate engineering technique with slight modifications. The physiochemical properties of CORM-2-SLNs were characterized and CO release from CORM-2-SLNs was assessed using a myoglobin assay. CO was slowly released from CORM-2-SLNs, was observed, and the half-life of CO release was 50 times longer than that of CORM-2. In vivo results demonstrate that intraperitoneal administration of CORM-2-SLNs (5 and 10 mg/kg/day, ip) once daily for seven consecutive days significantly reduced the mechanical allodynia and mechanical hyperalgesia compared with CORM-2 (10 mg/kg/day, ip). RT-PCR and Western blot analyses on days 7 and 14, revealed that treatment with CORM-2-SLNs resulted in greater reductions in the CCI-elevated levels of heme-oxygenase-2 (HO-2); inducible nitric oxide synthase (iNOS); neuronal NOS (nNOS); and inflammatory mediators (TNF-α, IBA-1, and GFAP) in the spinal cord and dorsal root ganglions compared with treatment with CORM-2. In contrast, HO-1 and IL-10 were significantly increased in the CORM-2-SLN-treated group compared with the group treated with CORM-2. These data indicate that CORM-2-SLNs are superior to CORM-2-S in alleviating mechanical allodynia and mechanical hyperalgesia.


Assuntos
Portadores de Fármacos/química , Hiperalgesia/tratamento farmacológico , Nanopartículas/química , Compostos Organometálicos/uso terapêutico , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Monóxido de Carbono/metabolismo , Feminino , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Hiperalgesia/patologia , Interleucina-10/genética , Interleucina-10/metabolismo , Lipídeos/química , Proteínas dos Microfilamentos/metabolismo , Modelos Biológicos , Neuralgia/complicações , Neuralgia/patologia , Óxido Nítrico Sintase Tipo I/genética , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Compostos Organometálicos/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Medula Espinal/patologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
9.
Mol Neurobiol ; 56(1): 267-277, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29691718

RESUMO

The aim of this study was to investigate the anti-inflammatory effects by ursodeoxycholic acid (UDCA) in rats with a spinal cord injury (SCI). A moderate mechanical compression injury was imposed on adult Sprague-Dawley (SD) rats. The post-injury locomotor functions were assessed using the Basso, Beattie, and Bresnahan (BBB) locomotor scale and the tissue volume of the injured region was analyzed using hematoxylin and eosin staining. The pro-inflammatory factors were evaluated by immunofluorescence (IF) staining, a quantitative real-time polymerase chain reaction (qRT-PCR), and enzyme-linked immunosorbent assay (ELISA). The phosphorylation of the extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 in mitogen-activated protein kinase (MAPK) signaling pathways related to inflammatory responses were measured by Western blot assays. UDCA improved the BBB scores and promoted the recovery of the spinal cord lesions. UDCA inhibited the expression of glial fibrillary acidic protein (GFAP), tumor necrosis factor-α (TNF-α), ionized calcium-binding adapter molecule 1 (iba1), and inducible nitric oxide synthase (iNOS). UDCA decreased the pro-inflammatory cytokines of TNF-α, interleukin 1-ß (IL-1ß), and interleukin 6 (IL-6) in the mRNA and protein levels. UDCA increased the anti-inflammatory cytokine interleukin 10 (IL-10) in the mRNA and protein levels. UDCA suppressed the phosphorylation of ERK, JNK, and the p38 signals. UDCA reduces pro-inflammatory responses and promotes functional recovery in SCI in rats. These results suggest that UDCA is a potential therapeutic drug for SCI.


Assuntos
Inflamação/tratamento farmacológico , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/fisiopatologia , Ácido Ursodesoxicólico/uso terapêutico , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Citocinas/genética , Citocinas/metabolismo , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Sistema de Sinalização das MAP Quinases , Proteínas dos Microfilamentos/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fosforilação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismos da Medula Espinal/patologia , Fator de Necrose Tumoral alfa/metabolismo , Ácido Ursodesoxicólico/farmacologia
11.
Acta Neuropathol Commun ; 6(1): 73, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-30086801

RESUMO

After spinal cord injury (SCI), neutrophil elastase (NE) released at injury site disrupts vascular endothelium integrity and stabilization. Angiopoietins (ANGPTs) are vascular growth factors that play an important role in vascular stabilization. We hypothesized that neutrophil elastase is one of the key determinants of vascular endothelium disruption/destabilization and affects angiopoietins expression after spinal cord injury. To test this, tubule formation and angiopoietins expression were assessed in endothelial cells exposed to different concentrations of recombinant neutropil elastase. Then, the expression of angiopoietin-1, angiopoietin-2, and neutrophil elastase was determined at 3 h and at 1, 3, 5, 7, 14, 21, and 28 days in a clinically relevant model of moderate compression (35 g for 5 min at T10) spinal cord injury. A dichotomy between the levels of angiopoietin-1 and angiopoietin-2 was observed; thus, we utilized a specific neutrophil elastase inhibitor (sivelestat sodium; 30 mg/kg, i.p., b.i.d.) after spinal cord injury. The expression levels of neutropil elastase and angiopoietin-2 increased, and that of angiopoietin-1 decreased after spinal cord injury in rats. The sivelestat regimen, optimized via a pharmacokinetics study, had potent effects on vascular stabilization by upregulating angiopoietin-1 via the AKT pathway and preventing tight junction protein degradation. Moreover, sivelestat attenuated the levels of inflammatory cytokines and chemokines after spinal cord injury and hence subsequently alleviated secondary damage observed as a reduction in glial scar formation and the promotion of blood vessel formation and stabilization. As a result, hindlimb locomotor function significantly recovered in the sivelestat-treated animals as determined by the Basso, Beattie, and Bresnahan scale and footprint analyses. Furthermore, sivelestat treatment attenuated neuropathic pain as assessed by responses to von Frey filaments after spinal cord injury. Thus, our result suggests that inhibiting neutropil elastase by administration of sivelestat is a promising therapeutic strategy to inhibit glial scar and promote functional recovery by upregulating angiopoietin-1 after spinal cord injury.


Assuntos
Angiopoietina-1/metabolismo , Cicatriz/tratamento farmacológico , Cicatriz/etiologia , Elastase de Leucócito/farmacologia , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/patologia , Angiopoietina-2/metabolismo , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Feminino , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/fisiologia , Glicina/análogos & derivados , Glicina/farmacologia , Humanos , Laminina/metabolismo , Elastase de Leucócito/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Ocludina/metabolismo , Peptídeos Opioides/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos , Inibidores de Serina Proteinase/farmacologia , Sulfonamidas/farmacologia , Fator de Crescimento Transformador beta1/metabolismo , Proteína da Zônula de Oclusão-1/metabolismo , Nociceptina
12.
Nano Lett ; 18(8): 4965-4975, 2018 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-29995418

RESUMO

Human mesenchymal stem cell (hMSC)-derived exosomes have been spotlighted as a promising therapeutic agent for cell-free regenerative medicine. However, poor organ-targeting ability and insufficient therapeutic efficacy of systemically injected hMSC-exosomes were identified as critical limitations for their further applications. Therefore, in this study we fabricated iron oxide nanoparticle (IONP)-incorporated exosome-mimetic nanovesicles (NV-IONP) from IONP-treated hMSCs and evaluated their therapeutic efficacy in a clinically relevant model for spinal cord injury. Compared to exosome-mimetic nanovesicles (NV) prepared from untreated hMSCs, NV-IONP not only contained IONPs which act as a magnet-guided navigation tool but also carried greater amounts of therapeutic growth factors that can be delivered to the target cells. The increased amounts of therapeutic growth factors inside NV-IONP were attributed to IONPs that are slowly ionized to iron ions which activate the JNK and c-Jun signaling cascades in hMSCs. In vivo systemic injection of NV-IONP with magnetic guidance significantly increased the amount of NV-IONP accumulating in the injured spinal cord. Accumulated NV-IONP enhanced blood vessel formation, attenuated inflammation and apoptosis in the injured spinal cord, and consequently improved spinal cord function. Taken together, these findings highlight the development of therapeutic efficacy-potentiated extracellular nanovesicles and demonstrate their feasibility for repairing injured spinal cord.


Assuntos
Nanopartículas de Magnetita/química , Células-Tronco Mesenquimais/química , Traumatismos da Medula Espinal/terapia , Animais , Apoptose , Materiais Biomiméticos , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Exossomos/química , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/química , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/ultraestrutura , Camundongos , Neovascularização Fisiológica , Células PC12 , Ratos , Transdução de Sinais , Traumatismos da Medula Espinal/patologia
13.
Front Pharmacol ; 9: 445, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29867457

RESUMO

α-asarone, a bioactive compound found in Acorus plant species, has been shown to exhibit neuroprotective, anti-oxidative, anti-inflammatory, and cognitive-enhancing effects. However, the effects of α-asarone on spinal cord injury (SCI) have not yet been elucidated. The present study investigated the effects of α-asarone on the mRNA of pro-inflammatory cytokines, macrophage polarization toward an anti-inflammatory M2 phenotype, and angiogenesis in rats with compressive SCI. α-Asarone was orally administered (10 mg/kg) once per day for 14 days following moderate static compression SCI. Compared to controls, α-asarone treatment significantly improved locomotor score, prevented neuroinflammation, and facilitated angiogenesis in the spinal cord at 14 days after SCI. Furthermore, α-asarone significantly reduced the TNF-α, IL-1ß, IL-6, monocyte chemoattractant protein 1 (MCP-1), macrophage inflammatory protein 2 (MIP-2), and inducible nitric oxide synthase (iNOS) levels but increased the IL-4, IL-10, and arginase 1 levels at 24 h after SCI. At 7 and 14 days after SCI, immunohistochemistry showed reduced reactive gliosis and neuroinflammation and an increased expression of M2 macrophage markers and angiogenesis. The results suggest that the inhibition of pro-inflammatory cytokines, macrophage polarization toward an anti-inflammatory M2 phenotype, and angiogenesis by α-asarone may be some of the mechanisms underlying the α-asarone-mediated neuroprotective effects on an injured spinal cord.

14.
Sci Rep ; 8(1): 3176, 2018 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-29453346

RESUMO

This study aimed to investigate the anti-inflammatory effects of tauroursodeoxycholic acid (TUDCA) after spinal cord injury (SCI) in rats. We induced an inflammatory process in RAW 264.7 macrophages, BV2 microglial cells, and bone marrow-derived macrophages (BMM) using lipopolysaccharide (LPS). The anti-inflammatory effects of TUDCA on LPS-stimulated RAW 264.7 macrophages, BV2 microglial cells, and BMMs were analyzed using nitric oxide (NO) assays, quantitative real-time polymerase chain reactions (qRT-PCR), and enzyme-linked immunosorbent assays (ELISA). The pathological changes in lesions of the spinal cord tissue were evaluated by hematoxylin & eosin (H&E) staining, luxol fast blue/cresyl violet-staining and immunofluorescent staining. TUDCA decreased the LPS-stimulated inflammatory mediator, NO. It also suppressed pro-inflammatory cytokines of tumor necrosis factor-α (TNF-α), interleukin 1-ß (IL-1ß), cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) in both mRNA and protein levels. In addition, TUDCA decreased prostaglandin E2 (PGE2). After SCI, TUDCA supported the recovery of the injury site and suppressed the expression of inflammatory cytokines such as iNOS, CD68 and CD86. In addition, TUDCA induced the expression of anti-inflammatory cytokine, Arg-1. In conclusion, TUDCA inhibits inflammatory responses in RAW 264.7 macrophages, BV2 microglial cells, and BMMs. TUDCA can be a potential alternative drug for SCI.


Assuntos
Anti-Inflamatórios/farmacologia , Células da Medula Óssea/citologia , Macrófagos/efeitos dos fármacos , Microglia/efeitos dos fármacos , Traumatismos da Medula Espinal/tratamento farmacológico , Ácido Tauroquenodesoxicólico/farmacologia , Animais , Citocinas/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Microglia/metabolismo , Células RAW 264.7 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Ácido Tauroquenodesoxicólico/uso terapêutico
15.
J Orthop Res ; 36(1): 244-253, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28741852

RESUMO

Genetic factors have been shown to be a small but significant predictor for osteoporosis and osteoporotic fracture risk. We performed a case-control association study to determine the association between miR-146a, miR-149, miR-196a2, and miR-499 polymorphisms and osteoporotic vertebral compression fracture (OVCF) susceptibility. In total, 286 unrelated postmenopausal Korean women (57 with OVCFs, 55 with non-OVCFs, and 174 healthy controls) were recruited. All subjects underwent dual energy X-ray absorptiometry to determine BMD at the lumbar spine and femoral neck. We focused on four single nucleotide polymorphisms (SNPs) of pre-miRNA sequences including miR-146aC>G (rs2910164), miR-149T>C (rs2292832), miR-196a2T>C (rs11614913), and miR-499A>G (rs3746444). Genotype frequencies of these four SNPs were determined using polymerase chain reaction-restriction fragment length polymorphism analysis. The TT genotype of miR-149aT>C was less frequent in subjects with OVCFs, suggesting a protective effect against OVCF risk (Odds ratio [OR], 0.435; 95% confidence interval [CI], 0.22-0.85, p = 0.014), whereas the miR-146aCG/ miR-196a2TC combined genotype was more frequent in OVCF patients (OR, 5.163; 95%CI, 1.057-25.21, p = 0.043), suggesting an increase in OVCF risk. Additionally, combinations of miR-146a, -149, -196a2, and -449 showed a significant association with increased prevalence of OVCFs in postmenopausal women. In particular, the miR-146aG/-149T/-196a2C/-449G allele combination was significantly associated with an increased risk of OVCF (OR, 35.01; 95% CI, 1.919-638.6, p = 0.001). Our findings suggest that the TT genotype of miR-149aT>C may contribute to decreased susceptibility to OVCF in Korean postmenopausal women. Conversely, the miR-146aCG/ miR-196a2TC combined genotype and the miR-146aG/-149T/-196a2C/-449G allele combination may contribute to increased susceptibility to OVCF. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:244-253, 2018.


Assuntos
Fraturas por Compressão/genética , Predisposição Genética para Doença , MicroRNAs/genética , Fraturas por Osteoporose/genética , Polimorfismo de Nucleotídeo Único , Idoso , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Pós-Menopausa
16.
Mol Neurobiol ; 55(3): 2577-2590, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28421532

RESUMO

After spinal cord injury (SCI), tight junction (TJ) protein degradation increases permeability and disrupts the blood-spinal cord barrier (BSCB). The BSCB is primarily formed of endothelial cell, which forms a specialized tight seal due to the presence of TJs. BSCB disruption after SCI allows neutrophil infiltration. Matrix metalloproteinase (MMP)-8 is believed to be mainly expressed by neutrophils and is quickly released upon neutrophil activation. Here, we determined whether MMP-8 is involved in the TJ protein degradation in endothelial cells and also determined its role in the neuroinflammation after SCI. MMP-8 recombinant protein treatment increases the TNF-α expression and decreased the TJ (occludin and zonula occludens-1) protein expression in the endothelial cells. Likewise, specific MMP-8 inhibitor (MMP-8I) significantly prevented the TNF-α-induced decrease in the expression of TJ protein in endothelial cells. Furthermore, MMP-8 expression was significantly increased 1 and 3 days after moderate compression (35 g for 5 min at T10 level) SCI, whereas TJ protein levels decreased as determined qRT-PCR, western blotting, and immunohistochemistry. MMP-8 was inhibited directly using a MMP-8I (5 mg/kg) and indirectly by reducing neutrophil infiltration with sivelestat sodium (50 mg/kg) or using the antioxidant N-acetyl-L-cysteine (100 mg/kg). The MMP-8I significantly decreased TNF-α expression, IL-6, and iNOS expression and increased TJ protein expression after SCI. In addition, MMP-8I significantly lessens the amount of Evans blue dye extravasation observed after injury. Thus, our result suggests that MMP-8 plays an imperative role in inflammation and degradation of TJ proteins. Increased MMP-8 expression was associated with the early inflammatory phase of SCI. Inhibiting MMP-8 significantly attenuated SCI-induced inflammation, BSCB breakdown, and cell injury.


Assuntos
Barreira Hematoencefálica/enzimologia , Modelos Animais de Doenças , Metaloproteinase 8 da Matriz/metabolismo , Inibidores de Metaloproteinases de Matriz/uso terapêutico , Traumatismos da Medula Espinal/enzimologia , Medula Espinal/enzimologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/patologia , Relação Dose-Resposta a Droga , Feminino , Inflamação/tratamento farmacológico , Inflamação/enzimologia , Inflamação/patologia , Inibidores de Metaloproteinases de Matriz/farmacologia , Ratos , Ratos Sprague-Dawley , Medula Espinal/efeitos dos fármacos , Medula Espinal/patologia , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/prevenção & controle , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/enzimologia , Junções Íntimas/patologia
17.
PLoS One ; 12(6): e0180673, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28665991

RESUMO

PURPOSE: The aim of this study was to investigate the anti-inflammatory effects of Ursodeoxycholic acid (UDCA) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. METHODS: We induced an inflammatory process in RAW 264.7 macrophages using LPS. The anti-inflammatory effects of UDCA on LPS-stimulated RAW 264.7 macrophages were analyzed using nitric oxide (NO). Pro-inflammatory and anti-inflammatory cytokines were analyzed by quantitative real time polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA). The phosphorylations of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 in mitogen-activated protein kinase (MAPK) signaling pathways and nuclear factor kappa-light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBα) signaling pathways were evaluated by western blot assays. RESULTS: UDCA decreased the LPS-stimulated release of the inflammatory mediator NO. UDCA also decreased the pro-inflammatory cytokines tumor necrosis factor-α (TNF-α), interleukin 1-α (IL-1α), interleukin 1-ß (IL-1ß), and interleukin 6 (IL-6) in mRNA and protein levels. In addition, UDCA increased an anti-inflammatory cytokine interleukin 10 (IL-10) in the LPS-stimulated RAW 264.7 macrophages. UDCA inhibited the expression of inflammatory transcription factor nuclear factor kappa B (NF-κB) in LPS-stimulated RAW 264.7 macrophages. Furthermore, UDCA suppressed the phosphorylation of ERK, JNK, and p38 signals related to inflammatory pathways. In addition, the phosphorylation of IκBα, the inhibitor of NF-κB, also inhibited by UDCA. CONCLUSION: UDCA inhibits the pro-inflammatory responses by LPS in RAW 264.7 macrophages. UDCA also suppresses the phosphorylation by LPS on ERK, JNK, and p38 in MAPKs and NF-κB pathway. These results suggest that UDCA can serve as a useful anti-inflammatory drug.


Assuntos
Anti-Inflamatórios/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Ácido Ursodesoxicólico/farmacologia , Animais , Western Blotting , Linhagem Celular , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Mediadores da Inflamação/metabolismo , Macrófagos/enzimologia , Macrófagos/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Proteínas Quinases/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
18.
PLoS One ; 11(5): e0155771, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27219012

RESUMO

Anoctamin1 (ANO1)/transmembrane protein 16A (TMEM16A), a calcium-activated chloride channel (CaCC), is involved in many physiological functions such as fluid secretion, smooth muscle contraction, nociception and cancer progression. To date, only a few ANO1 inhibitors have been described, and these have low potency and selectivity for ANO1. Here, we performed a high-throughput screening to identify highly potent and selective small molecule inhibitors of ANO1. Three novel ANO1 inhibitors were discovered from screening of 54,400 synthetic small molecules, and they were found to fully block ANO1 channel activity with an IC50 < 3 µM. Electrophysiological analysis revealed that the most potent inhibitor, 2-(4-chloro-2-methylphenoxy)-N-[(2-methoxyphenyl)methylideneamino]-acetamide (Ani9), completely inhibited ANO1 chloride current with submicromolar potency. Notably, unlike previous small-molecule ANO1 inhibitors identified to date, Ani9 displayed high selectivity for ANO1 as compared to ANO2, which shares a high amino acid homology to ANO1. In addition, Ani9 did not affect the intracellular calcium signaling and CFTR chloride channel activity. Our results suggest that Ani9 may be a useful pharmacological tool for studying ANO1 and a potential development candidate for drug therapy of cancer, hypertension, pain, diarrhea and asthma.


Assuntos
Acetamidas/farmacologia , Canais de Cloreto/antagonistas & inibidores , Hidrazonas/farmacologia , Proteínas de Membrana/metabolismo , Proteínas de Neoplasias/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Anoctamina-1 , Anoctaminas , Cálcio/metabolismo , Linhagem Celular , Canais de Cloreto/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Ensaios de Triagem em Larga Escala , Humanos , Proteínas de Membrana/genética , Proteínas de Neoplasias/genética , Homologia de Sequência de Aminoácidos
19.
Phys Rev E ; 94(6-1): 062307, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28085402

RESUMO

k-core percolation has served as a paradigmatic model of discontinuous percolation for a long time. Recently it was revealed that the order parameter of k-core percolation of random networks additionally exhibits critical behavior. Thus k-core percolation exhibits a hybrid phase transition. Unlike the critical behaviors of ordinary percolation that are well understood, those of hybrid percolation transitions have not been thoroughly understood yet. Here, we investigate the critical behavior of k-core percolation of Erdos-Rényi networks. We find numerically that the fluctuations of the order parameter and the mean avalanche size diverge in different ways. Thus, we classify the critical exponents into two types: those associated with the order parameter and those with finite avalanches. The conventional scaling relations hold within each set, however, these two critical exponents are coupled. Finally we discuss some universal features of the critical behaviors of k-core percolation and the cascade failure model on multiplex networks.

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