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Background Patients have the highest risk of subsequent fractures in the first few years after an initial fracture, yet models to predict short-term subsequent risk have not been developed. Purpose To develop and validate a deep learning prediction model for subsequent fracture risk using digitally reconstructed radiographs from hip CT in patients with recent hip fractures. Materials and Methods This retrospective study included adult patients who underwent three-dimensional hip CT due to a fracture from January 2004 to December 2020. Two-dimensional frontal, lateral, and axial digitally reconstructed radiographs were generated and assembled to construct an ensemble model. DenseNet modules were used to calculate risk probability based on extracted image features and fracture-free probability plots were output. Model performance was assessed using the C index and area under the receiver operating characteristic curve (AUC) and compared with other models using the paired t test. Results The training and validation set included 1012 patients (mean age, 74.5 years ± 13.3 [SD]; 706 female, 113 subsequent fracture) and the test set included 468 patients (mean age, 75.9 years ± 14.0; 335 female, 22 subsequent fractures). In the test set, the ensemble model had a higher C index (0.73) for predicting subsequent fractures than that of other image-based models (C index range, 0.59-0.70 for five of six models; P value range, < .001 to < .05). The ensemble model achieved AUCs of 0.74, 0.74, and 0.73 at the 2-, 3-, and 5-year follow-ups, respectively; higher than that of most other image-based models at 2 years (AUC range, 0.57-0.71 for five of six models; P value range, < .001 to < .05) and 3 years (AUC range, 0.55-0.72 for four of six models; P value range, < .001 to < .05). Moreover, the AUCs achieved by the ensemble model were higher than that of a clinical model that included known risk factors (2-, 3-, and 5-year AUCs of 0.58, 0.64, and 0.70, respectively; P < .001 for all). Conclusion In patients with recent hip fractures, the ensemble deep learning model using digital reconstructed radiographs from hip CT showed good performance for predicting subsequent fractures in the short term. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Li and Jaremko in this issue.
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Aprendizado Profundo , Fraturas do Quadril , Adulto , Humanos , Feminino , Idoso , Estudos Retrospectivos , Fraturas do Quadril/diagnóstico por imagem , Área Sob a Curva , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVES: This study aimed to examine the usability, feasibility, acceptability, and appropriateness of the information and communication technology for emergency medical services (ICT-EMS) systems to improve the transportation of emergency patients during the COVID-19 pandemic. METHODS: Emergency medical technicians (EMTs) (n = 229) employed at 7 fire stations operated by the North Chungcheong Fire Service Headquarters, South Korea were trained to use ICT-EMS devices prior to a 1-month implementation period. System Usability Scale (SUS), Feasibility of Intervention Measure (FIM), Acceptability of Intervention Measure (AIM), and Intervention Appropriateness Measure (IAM) questionnaires were conducted in the 4th week of the 1-month implementation period to assess the perceived usability, feasibility, acceptability, and appropriateness of the ICT-EMS systems. RESULTS: Among a total of 229 EMTs, 187 EMTs (81.7%) completed the survey. The overall SUS score was significantly low (score of 35.6) indicating an overall negative perception of the ICT-EMS systems. With regard to the feasibility, acceptability, and intervention appropriateness of ICT-EMS, roughly 50 (26.7%) participants agreed that ICT-EMS implementation was possible, appealing, and suitable. CONCLUSION: Many potential areas of improvement were identified within the ICT-EMS systems. System alterations regarding usability, feasibility, acceptability, and appropriateness may be necessary to successfully implement the ICT-EMS systems.
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COVID-19 , Serviços Médicos de Emergência , Auxiliares de Emergência , COVID-19/epidemiologia , Humanos , Pandemias , Transporte de PacientesRESUMO
The intestinal epithelium is one of the fastest renewing tissues in mammals and is a barrier against toxic substances such as alcohol. Excessive alcohol can induce intestinal damage leading to intestinal bowel diseases. Thus, the control of small intestinal epithelial cell (IEC) regeneration is thought to be important for homeostasis in response to epithelium damage. However, reports on how epithelial cells respond to small intestinal damage are scarce. We investigated the effects of alcohol consumption on small intestinal epithelial cells of mice. To verify that alcohol altered the small intestinal epithelium, we used 8-10 weeks old male C57BL/6J mice for models of chronic and binge alcohol consumption (the NIAAA model) in addition to an organoid model. Alcohol promoted the proliferative activity of IECs and intestinal stem cells (ISCs) in intestinal crypts. Alcohol consumption increased expression of the proliferation marker cyclin D1 and activated the p44/42 MAPK (Erk1/2) signaling pathway in small intestinal epithelial cells. The Wnt target genes were markedly increased in IECs from alcohol-treated mice. In the small intestinal organoid model exposed to alcohol, the organoid area and numbers of buds increased with alcohol concentrations up to 0.5% similar to in vivo observations. These results suggest that alcohol consumption stimulates the proliferation of small intestinal epithelial cells via Wnt signaling.
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Etanol/toxicidade , Mucosa Intestinal/efeitos dos fármacos , Alcoolismo/metabolismo , Alcoolismo/patologia , Animais , Consumo Excessivo de Bebidas Alcoólicas/metabolismo , Consumo Excessivo de Bebidas Alcoólicas/patologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/metabolismo , Intestino Delgado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Organoides/efeitos dos fármacos , Organoides/metabolismo , Organoides/patologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Células-Tronco/patologia , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/genéticaRESUMO
The Republic of Korea has a high prevalence of hepatitis B virus (HBV) infection, and the policies concerning costly antiviral medication have been revised recently. However, in the past 10 years, no related research on costs has been conducted. The objective of this study was to estimate the economic burden of viral hepatitis B and determine the trend of changes in its costs between 2002 and 2015. Claims data from the National Health Insurance Service were used. To identify viral hepatitis B cases, the ICD-10th code B16, B17.0, B18.0 and B18.1 were used based on a primary diagnosis. This study was conducted from a societal perspective regarding both direct and indirect costs. Annual costs were adjusted for inflation by calculations based on the 2015 costs. The number of patients with viral hepatitis B increased from 213 758 in 2002 to 342 672 in 2015. The total socio-economic costs increased from 127.1 million USD in 2002 to 459.1 million USD in 2015, mainly due to the increase in pharmaceutical costs, which accounted for the largest proportion of total costs since 2009-220.5 million USD in 2015, which was ~15 times higher than that in 2002. The healthcare costs for viral hepatitis B accounted for 0.13% of the national health expenditure in 2002, increasing to 0.31% in 2015. The economic burden of viral hepatitis B has increased in the Republic of Korea. It is therefore essential to reduce the healthcare costs of HBV infection by establishing an effective management policy.
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Efeitos Psicossociais da Doença , Hepatite B/economia , Hepatite B/epidemiologia , Programas Nacionais de Saúde/economia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Hepatite B/mortalidade , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Programas Nacionais de Saúde/tendências , Prevalência , República da Coreia/epidemiologia , Adulto JovemRESUMO
Background: Due to its high antioxidant activity, baicalein, a kind of flavonoid present in Radical Scutellariae, has various pharmacological effects. However, the protective effect against oxidative stress in Schwann cells, which plays an important role in peripheral neuropathy, has not yet been studied. In this study, the effects of baicalein on hydrogen peroxide (H2O2)-induced DNA damage and apoptosis in RT4-D6P2T Schwann cells were evaluated. Methods: Cell viability assay was performed using MTT assay and colony formation assay. Apoptosis was assessed by flow cytometry analysis and DNA fragmentation assay. The effects on DNA damage and ATP content were analyzed by comet method and luminometer. In addition, changes in protein expression were observed by Western blotting. Results: Our results show that baicalein significantly inhibits H2O2-induced cytotoxicity through blocking reactive oxygen species (ROS) generation. We also demonstrate that baicalein is to block H2O2-induced DNA damage as evidenced by inhibition of DNA tail formation and γH2AX phosphorylation. Moreover, baicalein significantly attenuated H2O2-induced apoptosis and mitochondrial dysfunction, and restored inhibition of ATP production. The suppression of apoptosis by baicalein in H2O2-stimulated cells was associated with reduction of increased Bax/Bcl-2 ratio, activation of caspase-9 and -3, and degradation of poly (ADP-ribose) polymerase. Conclusions: These results demonstrate that baicalein eliminates H2O2-induced apoptosis through conservation of mitochondrial function by the removal of ROS. Therefore, it is suggested that baicalein protects Schwann cells from oxidative stress, and may be beneficial for the prevention and treatment of peripheral neuropathy induced by oxidative stress.
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Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Flavanonas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Células de Schwann/fisiologia , Antioxidantes/uso terapêutico , Apoptose/genética , Sobrevivência Celular/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Flavanonas/uso terapêutico , Regulação da Expressão Gênica , Genes bcl-2 , Humanos , Peróxido de Hidrogênio/farmacologia , Oxidantes/farmacologia , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Doenças do Sistema Nervoso Periférico/metabolismo , Espécies Reativas de Oxigênio/antagonistas & inibidores , Células de Schwann/ultraestrutura , Proteína X Associada a bcl-2RESUMO
Phloroglucinol (PG) is a component of phlorotannins, which are abundant in marine brown alga species. Recent studies have shown that PG is beneficial in protecting cells from oxidative stress. In this study, we evaluated the protective efficacy of PG in HaCaT human skin keratinocytes stimulated with oxidative stress (hydrogen peroxide, H2O2). The results showed that PG significantly inhibited the H2O2-induced growth inhibition in HaCaT cells, which was associated with increased expression of heme oxygenase-1 (HO-1) by the activation of nuclear factor erythroid 2-related factor-2 (Nrf2). PG remarkably reversed H2O2-induced excessive ROS production, DNA damage, and apoptosis. Additionally, H2O2-induced mitochondrial dysfunction was related to a decrease in ATP levels, and in the presence of PG, these changes were significantly impaired. Furthermore, the increases of cytosolic release of cytochrome c and ratio of Bax to Bcl-2, and the activation of caspase-9 and caspase-3 by the H2O2 were markedly abolished under the condition of PG pretreatment. However, the inhibition of HO-1 function using zinc protoporphyrin, a HO-1 inhibitor, markedly attenuated these protective effects of PG against H2O2. Overall, our results suggest that PG is able to protect HaCaT keratinocytes against oxidative stress-induced DNA damage and apoptosis through activating the Nrf2/HO-1 signaling pathway.
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Apoptose/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Heme Oxigenase-1/metabolismo , Queratinócitos/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Floroglucinol/farmacologia , Substâncias Protetoras/farmacologia , Trifosfato de Adenosina/metabolismo , Antioxidantes/farmacologia , Caspase 3/metabolismo , Linhagem Celular , Citocromos c/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Queratinócitos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Purpose: Reactive oxygen species (ROS) contribute to the onset and progression of disease pathogenesis in a variety of organs, including age-related macular degeneration (AMD). Diphlorethohydroxycarmalol (DPHC), a phlorotannin compound, is one of the major components of the brown alga Ishige okamurae Yendo, and has been shown to have strong antioxidant capacity. The purpose of this study was to evaluate the protective effects of DPHC against oxidative stress (hydrogen peroxide, H2O2)-induced DNA damage and apoptosis in cultured ARPE19 retinal pigment epithelial (RPE) cells. Materials and methods: Cell viability was assessed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide assay. Intracellular ROS generation was measured by flow cytometer using 2',7'-dichlorofluorescin diacetate. The magnitude of apoptosis was measured by flow cytometry using the annexin V/propidium iodide double staining. DNA damage was evaluated by DNA fragmentation assay, comet assay and 8-hydroxy-2'-deoxyguanosine (8-OHdG) analysis. To observe the mitochondrial membrane potential, 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-imidacarbocyanine iodide staining was performed. In order to identify the underling mechanism of DPHC against H2O2-induced cellular alteration, we performed immune blotting. Results: The results of this study showed that the decreased survival rate brought about by H2O2 could be attributed to the induction of DNA damage and apoptosis accompanied by the increased production of ROS, which was remarkably reversed by DPHC. In addition, the loss of H2O2-induced mitochondrial membrane potential was significantly attenuated in the presence of DPHC. The inhibitory effect of DPHC on H2O2-induced apoptosis was associated with a reduced Bax/Bcl-2 ratio, the protection of the activation of caspase-9 and -3 and the inhibition of poly (ADP-ribose) polymerase cleavage, which was associated with the blockage of cytochrome c release to the cytoplasm. Conclusions: Our data proved that DPHC protects ARPE19 cells against H2O2-induced DNA damage and apoptosis by scavenging ROS and thus suppressing the mitochondrial-dependent apoptosis pathway. Therefore, this study suggests that DPHC has the therapeutic potential to prevent AMD by inhibiting oxidative stress-induced injury in RPE cells.
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Antioxidantes/farmacologia , Células Epiteliais/efeitos dos fármacos , Compostos Heterocíclicos com 3 Anéis/farmacologia , Epitélio Pigmentado da Retina/citologia , Apoptose/efeitos dos fármacos , Linhagem Celular , Dano ao DNA , Células Epiteliais/metabolismo , Células Epiteliais/fisiologia , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismoRESUMO
A novel and simple method for the fabrication of gold nanoparticle (AuNP) clusters was introduced for use as an efficient near-infrared (NIR) photothermal agent. Cationic surfactants were employed to assemble AuNPs into clusters, during which polyvinylpyrrolidone (PVP) was used to stabilize the AuNP clusters. Through this manner, AuNP clusters with a uniform shape and a narrow size distribution (55.4 ± 5.0 nm by electron microscope) were successfully obtained. A mechanism for the formation of AuNP clusters was studied and proposed. Electrostatic interactions between AuNPs and cationic surfactants, hydrophobic interactions between hydrocarbon chains of cationic surfactants, and repulsive steric interactions of PVP were found to play an important role with regard to the formation mechanism. Photothermal effect in the NIR range of the AuNP clusters was demonstrated; results presented a highly efficient photothermal conversion (with a maximum η of 65%) of the AuNP clusters. The clusters could be easily coated by a silica layer, enabling their biocompatibility and colloidal stability in physiological fluids. The easy-to-fabricate AuNP clusters showed high potential of use as an NIR photothermal agent for cancer therapy.
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Diallyl trisulfide (DATS) is one of the major sulfur-containing compounds in garlic oil. In this study, we analyzed the effects of DATS against hydrogen peroxide (H2O2)-induced oxidative stress in C2C12 myoblasts. DATS preconditioning significantly attenuated H2O2-induced growth inhibition and DNA damage, as well as apoptosis by decreasing the generation of ROS. Treatment with DATS alone effectively upregulated the expression of nuclear factor-erythroid 2-related factor 2 (Nrf2) and thioredoxin reductase 1 (TrxR1), which was associated with the increased phosphorylation of Nrf2. However, the protective effects of DATS against H2O2-induced growth reduction and ROS accumulation were significantly abolished by auranofin, an inhibitor of TrxR activity. Moreover, DATS-mediated phosphorylation of Nrf2 and induction of TrxR1 were markedly reduced by genetic silencing of Nrf2. DATS treatment also induced the phosphorylation extracellular signal-regulating kinase (ERK), and analysis using specific inhibitors of cellular signaling pathways demonstrated that only ERK activation was involved in Nrf2 phosphorylation and TrxR1 induction. In addition, the cytoprotective potentials were abrogated in C2C12 cells pretreated with an ERK specific inhibitor. The results demonstrate that DATS protects against oxidative stress-induced DNA damage and apoptosis in C2C12 cells in part through the activation of Nrf2-mediated TrxR1 induction via the ERK signaling pathway.
Assuntos
Compostos Alílicos/administração & dosagem , Mioblastos/efeitos dos fármacos , Mioblastos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/fisiologia , Sulfetos/administração & dosagem , Tiorredoxina Redutase 1/metabolismo , Animais , Antioxidantes/administração & dosagem , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/fisiologia , Peróxido de Hidrogênio/administração & dosagem , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/fisiologia , Camundongos , Mioblastos/patologia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismoRESUMO
Flow cytometry and fluorescence activated cell sorting techniques were designed to realize configurable classification and separation of target cells. A number of cell phenotypes with different functionalities have recently been revealed. Before simultaneous selective capture of cells, it is desirable to label different samples with the corresponding dyes in a multiplexing manner to allow for a single analysis. However, few methods to obtain multiple fluorescent colors for various cell types have been developed. Even when restricted laser sources are employed, a small number of color codes can be expressed simultaneously. In this study, we demonstrate the ability to manifest DNA nanostructure-based multifluorescent colors formed by a complex of dyes. Highly precise self-assembly of fluorescent dye-conjugated oligonucleotides gives anisotropic DNA nanostructures, Y- and tree-shaped DNA (Y-DNA and T-DNA, respectively), which may be used as platforms for fluorescent codes. As a proof of concept, we have demonstrated seven different fluorescent codes with only two different fluorescent dyes using T-DNA. This method provides maximum efficiency for current flow cytometry. We are confident that this system will provide highly efficient multiplexed fluorescent detection for bioanalysis compared with one-to-one fluorescent correspondence for specific marker detection.
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Separação Celular/métodos , DNA Bacteriano , Coloração e Rotulagem/métodos , Separação Celular/instrumentação , Colorimetria , DNA Bacteriano/química , Citometria de Fluxo/instrumentação , Coloração e Rotulagem/instrumentaçãoRESUMO
The Segway, which is a popular vehicle nowadays, is an uncertain nonlinear system and has an unknown time-varying control coefficient. Thus, we should consider the unknown time-varying control coefficient and model uncertainties to design the controller. Motivated by this observation, we propose a robust control for the Segway with unknown control coefficient and model uncertainties. To deal with the time-varying unknown control coefficient, we employ the Nussbaum gain technique. We introduce an auxiliary variable to solve the underactuated problem. Due to the prescribed performance control technique, the proposed controller does not require the adaptive technique, neural network, and fuzzy logic to compensate the uncertainties. Therefore, it can be simple. From the Lyapunov stability theory, we prove that all signals in the closed-loop system are bounded. Finally, we provide the simulation results to demonstrate the effectiveness of the proposed control scheme.
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Obesity is a serious medical condition causing various diseases such as heart disease, type-2 diabetes, and cancer. Fat cells (adipocytes) play an important role in the generation of energy through hydrolysis of lipids they accumulate. Therefore, induction of lipolysis (breakdown of lipids into fatty acids and glycerol), is one of the ways to treat obesity. In the present study, we investigated the lipolytic effect of widdrol in 3T3-L1 adipocytes and its mechanism. Widdrol considerably increased the amount of glycerol released from 3T3-L1 adipocytes into the medium in a time- and dose-dependent manner. To determine the mechanism of this effect, we investigated the alterations in glycerol release and protein expression in 3T3-L1 adipocytes treated with widdrol alone or widdrol and inhibitors of proteins involved in the cAMP-dependent pathway or cAMP-independent PKC-MAPK pathway, which are known to induce lipolysis in adipocytes. The adenylyl cyclase inhibitor SQ-22536, PLA2 inhibitor dexamethasone, PI3K inhibitor wortmannin, and PKA inhibitor H-89, which were used to investigate the involvement of the cAMP-dependent pathway, did not affect the lipolytic effect of widdrol. Widdrol-induced phosphorylation of PKC, MEK, and ERK, which are related to the PKC-MAPK pathway, and their phosphorylation was inhibited by their inhibitors (H-7, U0126, and PD-98059, respectively). Moreover, the increase in glycerol release induced by widdrol was almost completely blocked by PKC, MEK, and ERK inhibitors. These results suggest that widdrol induces lipolysis through activation of the PKC-MEK-ERK pathway.
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Adipócitos/efeitos dos fármacos , Fármacos Antiobesidade/farmacologia , Benzocicloeptenos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Lipólise/efeitos dos fármacos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteína Quinase C/metabolismo , Células 3T3-L1 , Adipócitos/enzimologia , Animais , Relação Dose-Resposta a Droga , Ativação Enzimática , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Glicerol/metabolismo , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Fosforilação , Proteína Quinase C/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fatores de TempoRESUMO
High temperatures (30-36 °C) inhibited astaxanthin accumulation in Haematococcus pluvialis under photoautotrophic conditions. The depression of carotenogenesis was primarily attributed to excess intracellular less reactive oxygen species (LROS; O2 (-) and H2O2) levels generated under high temperature conditions. Here, we show that the heat stress-driven inefficient astaxanthin production was improved by accelerating the iron-catalyzed Haber-Weiss reaction to convert LROS into more reactive oxygen species (MROS; O2 and OH·), thereby facilitating lipid peroxidation. As a result, during 18 days of photoautotrophic induction, the astaxanthin concentration of cells cultured in high temperatures in the presence of iron (450 µM) was dramatically increased by 75 % (30 °C) and 133 % (36 °C) compared to that of cells exposed to heat stress alone. The heat stress-driven Haber-Weiss reaction will be useful for economically producing astaxanthin by reducing energy cost and enhancing photoautotrophic astaxanthin production, particularly outdoors utilizing natural solar radiation including heat and light for photo-induction of H. pluvialis.
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Clorófitas/metabolismo , Processos Autotróficos/efeitos da radiação , Clorófitas/crescimento & desenvolvimento , Clorófitas/efeitos da radiação , Temperatura Alta , Luz , Espécies Reativas de Oxigênio/metabolismo , Xantofilas/biossínteseRESUMO
This study was designed to examine the protective effects of the marine brown algae Petalonia binghamiae against oxidative stress-induced cellular damage and to elucidate the underlying mechanisms. P. binghamiae methanol extract (PBME) prevented hydrogen peroxide (H2O2)-induced growth inhibition and exhibited scavenging activity against intracellular reactive oxygen species (ROS) induced by H2O2 in mouse-derived C2C12 myoblasts. PBME also significantly attenuated H2O2-induced comet tail formation in a comet assay, histone γH2A.X phosphorylation, and annexin V-positive cells, suggesting that PBME prevented H2O2-induced cellular DNA damage and apoptotic cell death. Furthermore, PBME increased the levels of heme oxygenase-1 (HO-1), a potent antioxidant enzyme, associated with the induction of nuclear factor-erythroid 2 related factor 2 (Nrf2). However, zinc protoporphyrin IX, a HO-1 competitive inhibitor, significantly abolished the protective effects of PBME on H2O2-induced ROS generation, growth inhibition, and apoptosis. Collectively, these results demonstrate that PBME augments the antioxidant defense capacity through activation of the Nrf2/HO-1 pathway.
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Heme Oxigenase-1/metabolismo , Mioblastos/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Phaeophyceae/química , Substâncias Protetoras/farmacologia , Regulação para Cima/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Células Cultivadas , Dano ao DNA/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Metanol/química , Camundongos , Mioblastos/metabolismo , Fosforilação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
BACKGROUND: The migration of vascular smooth muscle cells from the tunica media to the subendothelial region may be a key event in the development of atherosclerosis after arterial injury. In this study, we investigated the potential mechanisms underlying the anti-atherosclerotic effects of Schisandrae Semen essential oil (SSeo) in human aortic smooth muscle cells (HASMCs). METHODS: Metalloproteinase-2/9 (MMP-2/9) activity was evaluated by gelatin zymography and gelatinase activity assay kit. The possible mechanisms underlying SSeo-mediated reduction of by tumor necrosis factor (TNF)-α-induced cell invasion and inhibition of secreted and cytosolic MMP-9 production in HASMCs were investigated. RESULTS: Our results indicate that SSeo treatment has an inhibitory effect on activation as well as expression of MMP-9 induced by TNF-α in HASMCs in a dose-dependent manner without significant cytotoxicity. SSeo attenuated nuclear translocation of TNF-α-mediated nuclear factor-kappa B (NF-κB) and blocked degradation of the NF-κB inhibitor proteins as well as the production of reactive oxygen species. SSeo also reduced TNF-α-induced production of pro-inflammatory mediators such as nitric oxide and prostaglandin E2 and inhibited inducible nitric oxide synthase and cyclooxygenase-2 expression in HASMCs. Furthermore, the Matrigel migration assay showed that SSeo effectively reduced TNF-α-induced HASMC migration compared with that in the control group. CONCLUSIONS: Taken together, these results suggest that SSeo treatment suppresses TNF-α-induced HASMC migration by selectively inhibiting MMP-9 expression, which was associated with suppression of the NF-κB signaling pathway. Taken together, these results suggest that SSeo has putative potential anti-atherosclerotic activity.
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Aterosclerose/metabolismo , Movimento Celular/efeitos dos fármacos , Metaloproteinase 9 da Matriz/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Óleos Voláteis/farmacologia , Schisandra/química , Fator de Necrose Tumoral alfa/metabolismo , Aorta/efeitos dos fármacos , Aorta/metabolismo , Aterosclerose/prevenção & controle , Ciclo-Oxigenase 2/metabolismo , Humanos , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , NF-kappa B/metabolismo , Óleos Voláteis/isolamento & purificação , Óleos Voláteis/uso terapêutico , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Sementes/química , Transdução de Sinais/efeitos dos fármacosRESUMO
BACKGROUND: Sargassum horneri, an edible marine brown alga, is typically distributed along the coastal seas of Korea and Japan. Although several studies have demonstrated the anti-oxidative activity of this alga, the regulatory mechanisms have not yet been defined. The aim of the present study was to examine the cytoprotective effects of S. horneri against oxidative stress-induced cell damage in C2C12 myoblasts. METHODS: We demonstrated the anti-oxidative effects of a methanol extract of S. horneri (SHME) in a hydrogen peroxide (H2O2)-stimulated C2C12 myoblast model. Cytotoxicity was determined using the 3-(4,5-dimetylthiazol-2-yl)-2,5-diphenyl-tetrazolium assay and mode of cell death by cell cycle analysis. DNA damage was measured using a comet assay and expression of phospho-histone γH2A.X (p-γH2A.X). Levels of cellular oxidative stress as reactive oxygen species (ROS) accumulation were measured using 2',7'-dichlorofluorescein diacetate. The involvement of selected genes in the oxidative stress-mediated signaling pathway was explored using Western blot analysis. RESULTS: SHME attenuated H2O2-induced growth inhibition and exhibited scavenging activity against intracellular ROS that were induced by H2O2. The SHME also inhibited comet tail formation, p-γH2A.X expression, and the number of sub-G1 hypodiploid cells, suggesting that it prevents H2O2-induced cellular DNA damage and apoptotic cell death. Furthermore, the SHME significantly enhanced the expression of heme oxygenase-1 (HO-1) associated with induction of nuclear factor-erythroid 2 related factor 2 (Nrf2) in a time- and concentration-dependent manner. Moreover, the protective effect of the SHME on H2O2-induced C2C12 cell damage was significantly abolished by zinc protoporphyrin IX, a HO-1 competitive inhibitor, in C2C12 cells. CONCLUSIONS: These findings suggest that the SHME augments cellular antioxidant defense capacity through both intrinsic free radical scavenging activity and activation of the Nrf2/HO-1 pathway, protecting C2C12 cells from H2O2-induced oxidative cytotoxicity.
Assuntos
Antioxidantes/farmacologia , Produtos Biológicos/farmacologia , Heme Oxigenase-1/metabolismo , Músculo Esquelético/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Sargassum , Animais , Apoptose/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Japão , Camundongos , Músculo Esquelético/metabolismo , Mioblastos Esqueléticos/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , República da Coreia , Transdução de Sinais/efeitos dos fármacos , Ativação Transcricional , Regulação para CimaRESUMO
Intracellular Ca(2+) signal is a key regulator of axonal growth during brain development. As transient receptor potential (TRP) channels are permeable to Ca(2+) and mediate numerous brain functions, it is conceivable that many TRP channels would regulate neuronal differentiation. We therefore screened TRP channels that are involved in the regulation of neurite growth. Among the TRP channels, the Trpm2 level was inversely associated with neurite growth. TRPM2 was highly expressed in embryonic brain. Pharmacological perturbation or knockdown of TRPM2 markedly increased the axonal growth, whereas its overexpression inhibited the axonal growth. Addition of ADP ribose, an endogenous activator of TRPM2, to PC12 cells significantly repressed the axonal growth. TRPM2 was actively involved in the neuronal retraction induced by cerebrospinal fluid-rich lysophosphatidic acid (LPA). More importantly, neurons isolated from the brain of Trpm2-deficient mice have significantly longer neurites with a greater number of spines than those obtained from the brain of wild-type mice. Therefore, we conclude that TRPM2 mediates the LPA-induced suppression of axonal growth, which provides a long-sought mechanism underlying the effect of LPA on neuronal development.
Assuntos
Encéfalo/metabolismo , Neuritos/metabolismo , Neurogênese , Canais de Cátion TRPM/metabolismo , Adenosina Difosfato Ribose/farmacologia , Animais , Encéfalo/citologia , Encéfalo/embriologia , Células Cultivadas , Células HEK293 , Humanos , Lisofosfolipídeos/farmacologia , Camundongos , Neuritos/efeitos dos fármacos , Células PC12 , Ratos , Canais de Cátion TRPM/genéticaRESUMO
Copper sulfide, CuS, was synthesized by an aqueous sonochemical method and it was investigated the effect of pH on crystal characteristics of CuS and IR absorbance. The formed CuS has main peaks as 27.68 degrees, 29.28 degrees, 31.79 degrees, 32.85 degrees, 47.94 degrees, 52.72 degrees and 59.3 degrees with the hexagonal structure. Average diameter of CuS was about 18 nm and molar ratio of Cu:S was as 1:1. The CuS prepared at pH 11 presents the highest visible light transmittance of 82.6% and that at pH 4 presents the highest IR rejected of 93.8%. The formation of CuS was affected by pH and led to new absorption band in the IR region. The CuS nanoparticles from this study could be used as thermal insulating materials for car- and house-window films with a high IR-cut.
RESUMO
OBJECTIVE: Neurodegeneration induced by inflammatory stress in multiple sclerosis (MS) leads to long-term neurological disabilities that are not amenable to current immunomodulatory therapies. METHODS AND RESULTS: Here, we report that neuronal downregulation of Splicing factor 3b subunit 2 (SF3B2), a component of U2 small nuclear ribonucleoprotein (snRNP), preserves retinal ganglion cell (RGC) survival and axonal integrity in experimental autoimmune encephalomyelitis (EAE)-induced mice. By employing an in vitro system recapitulating the inflammatory environment of MS lesion, we show that when SF3B2 levels are downregulated, cell viability and axon integrity are preserved in cortical neurons against inflammatory toxicity. Notably, knockdown of SF3B2 suppresses the expression of injury-response and necroptosis genes and prevents activation of Sterile Alpha and TIR Motif Containing 1 (Sarm1), a key enzyme that mediates programmed axon degeneration. INTERPRETATION: Together, these findings suggest that the downregulation of SF3B2 is a novel potential therapeutic target to prevent secondary neurodegeneration in MS.
Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Fatores de Processamento de RNA , Células Ganglionares da Retina , Animais , Camundongos , Proteínas do Domínio Armadillo/genética , Proteínas do Domínio Armadillo/metabolismo , Axônios/patologia , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Encefalomielite Autoimune Experimental/patologia , Esclerose Múltipla/genética , Esclerose Múltipla/patologia , Células Ganglionares da Retina/metabolismo , Células Ganglionares da Retina/patologia , Fatores de Processamento de RNA/genéticaRESUMO
Objectives: Rapid and accurate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) diagnostic tests are crucial for controlling the spread of infections in emergency settings. This study evaluated the diagnostic accuracy of a point-of-care (POC) test based on loop-mediated isothermal amplification (LAMP) that produces rapid results within 30 min. Methods: We prospectively included adult patients (age >19 years) who were diagnosed with SARS-CoV-2 infection within the last 3 days and symptomatic patients who had visited the emergency room. Posterior nasopharyngeal (PNP) swabs and throat swabs collected by physicians were used to test the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and Cohen's Kappa coefficient (k) of the POC index and reference reverse transcription quantitative polymerase chain reaction (RT-qPCR) test devices. Results: Of the 352 participants, 102 (29.0%) tested positive via the RT-PCR-based reference test device; the RT-LAMP-based POC test had a sensitivity of 70.6% and specificity of 98.0%, with 93.5% PPV, 89.1% NPV, 35.5% PLR, and 3.4% NLR. Cohen's k correlation of results from the two devices was 0.74. The cycle threshold value between the positive and negative POC test results differed (17.6 vs. 24.6, p < 0.001). Conclusions: The RT-LAMP POC test in the emergency medical setting has a fair predictive value in high viral load cases in terms of infectivity.