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1.
Proc Natl Acad Sci U S A ; 121(23): e2316858121, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38805270

RESUMO

In mammals, CLOCK and BMAL1 proteins form a heterodimer that binds to E-box sequences and activates transcription of target genes, including Period (Per). Translated PER proteins then bind to the CLOCK-BMAL1 complex to inhibit its transcriptional activity. However, the molecular mechanism and the impact of this PER-dependent inhibition on the circadian clock oscillation remain elusive. We previously identified Ser38 and Ser42 in a DNA-binding domain of CLOCK as phosphorylation sites at the PER-dependent inhibition phase. In this study, knockout rescue experiments showed that nonphosphorylatable (Ala) mutations at these sites shortened circadian period, whereas their constitutive-phospho-mimetic (Asp) mutations completely abolished the circadian rhythms. Similarly, we found that nonphosphorylatable (Ala) and constitutive-phospho-mimetic (Glu) mutations at Ser78 in a DNA-binding domain of BMAL1 also shortened the circadian period and abolished the rhythms, respectively. The mathematical modeling predicted that these constitutive-phospho-mimetic mutations weaken the DNA binding of the CLOCK-BMAL1 complex and that the nonphosphorylatable mutations inhibit the PER-dependent displacement (reduction of DNA-binding ability) of the CLOCK-BMAL1 complex from DNA. Biochemical experiments supported the importance of these phosphorylation sites for displacement of the complex in the PER2-dependent inhibition. Our results provide direct evidence that phosphorylation of CLOCK-Ser38/Ser42 and BMAL1-Ser78 plays a crucial role in the PER-dependent inhibition and the determination of the circadian period.


Assuntos
Fatores de Transcrição ARNTL , Proteínas CLOCK , Relógios Circadianos , Proteínas Circadianas Period , Animais , Humanos , Camundongos , Fatores de Transcrição ARNTL/metabolismo , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/química , Relógios Circadianos/genética , Ritmo Circadiano/fisiologia , Ritmo Circadiano/genética , Proteínas CLOCK/metabolismo , Proteínas CLOCK/genética , DNA/metabolismo , Células HEK293 , Mutação , Células NIH 3T3 , Proteínas Circadianas Period/metabolismo , Proteínas Circadianas Period/genética , Fosforilação , Ligação Proteica , Domínios Proteicos
2.
Proc Natl Acad Sci U S A ; 119(8)2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35193959

RESUMO

In metazoan organisms, circadian (∼24 h) rhythms are regulated by pacemaker neurons organized in a master-slave hierarchy. Although it is widely accepted that master pacemakers and slave oscillators generate rhythms via an identical negative feedback loop of transcription factor CLOCK (CLK) and repressor PERIOD (PER), their different roles imply heterogeneity in their molecular clockworks. Indeed, in Drosophila, defective binding between CLK and PER disrupts molecular rhythms in the master pacemakers, small ventral lateral neurons (sLNvs), but not in the slave oscillator, posterior dorsal neuron 1s (DN1ps). Here, we develop a systematic and expandable approach that unbiasedly searches the source of the heterogeneity in molecular clockworks from time-series data. In combination with in vivo experiments, we find that sLNvs exhibit higher synthesis and turnover of PER and lower CLK levels than DN1ps. Importantly, light shift analysis reveals that due to such a distinct molecular clockwork, sLNvs can obtain paradoxical characteristics as the master pacemaker, generating strong rhythms that are also flexibly adjustable to environmental changes. Our results identify the different characteristics of molecular clockworks of pacemaker neurons that underlie hierarchical multi-oscillator structure to ensure the rhythmic fitness of the organism.


Assuntos
Proteínas CLOCK/genética , Relógios Circadianos/fisiologia , Neurônios/metabolismo , Animais , Relógios Biológicos/fisiologia , Encéfalo/fisiologia , Proteínas CLOCK/metabolismo , Ritmo Circadiano/fisiologia , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Expressão Gênica/genética , Regulação da Expressão Gênica/genética , Proteínas Circadianas Period/metabolismo
3.
Skin Res Technol ; 30(3): e13655, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38481085

RESUMO

BACKGROUND: The stratum corneum (SC), the outermost layer of the skin epidermis, acts as an effective bi-directional barrier, preventing water loss (inside-outside barrier) and entry of foreign substances (outside-inside barrier). Although transepidermal water loss (TEWL) is a widely-used measure of barrier function, it represents only inside-outside protection. Therefore, we aimed to establish a non-invasive method for quantitative evaluation of the outside-inside barrier function and visually present a skin barrier model. MATERIALS AND METHODS: Skin barrier damage was induced by applying a closed patch of 1% sodium dodecyl sulfate to the forearms of eight participants; they were instructed to apply a barrier cream on a designated damaged area twice daily for 5 days. The SC barrier was evaluated by measuring TEWL and fluorescein sodium salt penetration rate before, immediately after, and 5 days after damage. The penetration rate was assessed using tape-stripping (TS) technique and fluorescence microscopy. RESULTS: The rates of fluorescein sodium salt penetration into the lower layers of SC differed significantly based on the degree of skin barrier damage. The correlation between penetration rate and TEWL was weak after two rounds of TS and became stronger after subsequent rounds. Five days after skin barrier damage, the penetration rate of all layers differed significantly between areas with and without the barrier cream application. CONCLUSION: Our findings demonstrated that the penetration rate was dependent on skin barrier conditions. The penetration rate and corresponding fluorescence images are suitable quantitative indicators that can visually represent skin barrier conditions.


Assuntos
Dermatopatias , Perda Insensível de Água , Humanos , Fluoresceína/metabolismo , Fluoresceína/farmacologia , Epiderme/metabolismo , Pele/metabolismo , Dermatopatias/metabolismo , Água/metabolismo , Emolientes/farmacologia
4.
BMC Genomics ; 23(1): 632, 2022 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-36057546

RESUMO

BACKGROUND: Gummy stem blight (GSB), caused by Didymella bryoniae (syn. Stagonosporopsis cucurbitacearum), produces devastating symptoms on whole plants of watermelon (Citrullus lanatus) and other cucurbits, significantly reducing yield and quality. Identification of genetic determinants and sources of resistance to this devastating GSB disease in watermelon is essential for developing resistant varieties. RESULTS: In this study, we aimed at identifying quantitative trait loci (QTLs) linked to GSB resistance in melon. We identified the genome-wide single nucleotide polymorphisms (SNPs) by genotyping by sequencing (GBS) of an F2 population developed from C. lanatus lines, 'PI 279461' (resistant) ✕ 'PI 223764' (susceptible). Inheritance analysis indicated that resistance to GSB is a multi-genic trait in this population. Three QTLs namely, ClGSB1.1, ClGSB10.1, and ClGSB11.1 associated with GSB resistance, explaining approximately 10% of the phenotypic variation, were identified. Among these, the QTL ClGSB1.1 on chromosome 1 is identified as a major QTL harboring five candidate genes associated with GSB resistance including two RLKs (ClC01G014900 and ClC01G015010), two WRKY transcription factors (ClC01G014910 and ClC01G014990), and one AvrRpt-cleavage domain protein (ClC01G015130). CONCLUSION: Two high resolution melting (HRM) markers, WmGSB1.1-2 and WmGSB1.1-7 having a high positive correlation with the phenotypic variations, were developed. Five potential candidate genes were predicted to be associated with GSB resistance. These findings will help breeders to develop watermelon cultivars resistant to GSB.


Assuntos
Ascomicetos , Citrullus , Ascomicetos/genética , Citrullus/genética , Doenças das Plantas/genética , Locos de Características Quantitativas
5.
Exp Dermatol ; 31(5): 743-752, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34882846

RESUMO

Matrix metalloproteinases (MMPs) play a key role in tissue remodelling by cleaving extracellular matrix (ECM) components. In the skin, UV irradiation increases expression of MMPs that causes dysregulation of ECM homeostasis in dermis, leading to acceleration of skin aging. However, the mediator(s) that links UV irradiation to the upregulation of MMPs have not been fully defined. Previously, we showed that UVB irradiation activated transglutaminase 2 (TG2) in keratinocytes, eliciting an inflammatory response by activating NF-κB signalling. In this study, we reported the role of TG2 in mediating the UVB-induced expression of MMP-1. In human dermal fibroblasts, UVB irradiation enhanced the expression and activity of TG2, which in turn promotes the expression of MMP-1. Analyses of MMP-1 promoter showed that activation of the NF-κB signalling pathway, rather than AP-1, was responsible for the TG2-mediated upregulation of MMP-1. Moreover, Western blot analysis revealed that TG2 increased the activity of NF-κB by inhibiting degradation of p65 in the nucleus. Furthermore, ex vivo skin from TG2-knockout mice exhibited significantly reduced levels of MMP-1 compared to that from wild-type mice. These results indicate that TG2 functions as a mediator for the UVB-induced expression of MMP-1 in dermal fibroblasts, providing a new target for preventing skin photodamage.


Assuntos
Metaloproteinase 1 da Matriz , Proteína 2 Glutamina gama-Glutamiltransferase , Animais , Fibroblastos/metabolismo , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/metabolismo , Metaloproteinases da Matriz/metabolismo , Camundongos , NF-kappa B/metabolismo , Pele/metabolismo , Raios Ultravioleta/efeitos adversos
6.
Intervirology ; 65(3): 134-143, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34736262

RESUMO

INTRODUCTION: Recombination-activating gene (Rag) 1 and Rag2, which are essential in V(D)J recombination, play a crucial role in B- and T-cell maturation. METHOD: We investigated the effects of Rag2 deficiency in clustered regularly interspaced short palindromic repeats/Cas9-mediated FVB-Rag2 knockout (KO) and wild-type (WT) mice infected with mouse adenovirus type 1 (MAV-1) via the intranasal route. RESULTS: MAV-1 infection caused more severe histopathological changes in FVB-Rag2 KO mice than in WT mice. FVB-Rag2 KO mice exhibited moderate to severe inflammation on day 4 and severe inflammation on day 8 post infection. In contrast, WT mice showed mild inflammation on day 4 and mild to severe inflammation on day 8 post infection, including interstitial pneumonia and inflammatory cell infiltration in the lungs and liver. Viral loads in the spleen and kidneys were significantly higher in FVB-Rag2 KO mice than in WT mice on day 8 post infection. Levels of cytokines and chemokines, including macrophage inflammatory protein-1α, induced protein 10, interferon (IFN)-α, IFN-γ, and tumor necrosis factor alpha, were upregulated in the spleens of FVB-Rag2 KO mice compared with those of WT mice. The upregulation of several cytokines occurred concurrently with the histopathological changes. MAV-1 infection induced more severe systemic infection in FVB-Rag2 KO mice than in WT mice. CONCLUSION: In mice, Rag2 deficiency induces inflammatory cell recruitment via the upregulation of cytokine and chemokine levels. The MAV-1 infection model can be utilized to assess the efficacy and safety of therapeutic agents for human adenoviral diseases.


Assuntos
Infecções por Adenoviridae , Citocinas , Adenoviridae/genética , Animais , Citocinas/metabolismo , Proteínas de Ligação a DNA/genética , Inflamação , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Imunodeficiência Combinada Severa
7.
Int J Mol Sci ; 23(5)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35269849

RESUMO

UV-irradiation induces the secretion of double-stranded RNA (dsRNA) derived from damaged noncoding RNAs in keratinocytes, which enhance the expression of matrix metalloproteinases (MMP) in non-irradiated dermal fibroblasts, leading to dysregulation of extracellular matrix homeostasis. However, the signaling pathway responsible for dsRNA-induced MMP expression has not been fully understood. Transglutaminase 2 (TG2) is an enzyme that modifies substrate proteins by incorporating polyamine or crosslinking of proteins, thereby regulating their functions. In this study, we showed that TG2 mediates dsRNA-induced MMP-1 expression through NF-κB activation. Treatment of poly(I:C), a synthetic dsRNA analogue binding to toll-like receptor 3 (TLR3), generates ROS, which in turn activates TG2 in dermal fibroblast. Subsequently, TG2 activity enhances translocation of p65 into the nucleus, where it augments transcription of MMP. We confirmed these results by assessing the level of MMP expression in Tlr3-/-, TG2-knockdowned and Tgm2-/- dermal fibroblasts after poly(I:C)-treatment. Moreover, treatment with quercetin showed dose-dependent suppression of poly(I:C)-induced MMP expression. Furthermore, ex vivo cultured skin from Tgm2-/- mice exhibited a significantly reduced level of MMP mRNA compared with those from wild-type mice. Our results indicate that TG2 is a critical regulator in dsRNA-induced MMP expression, providing a new target and molecular basis for antioxidant therapy in preventing collagen degradation.


Assuntos
Metaloproteinase 1 da Matriz , RNA de Cadeia Dupla , Animais , Células Cultivadas , Fibroblastos/metabolismo , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/genética , Metaloproteinase 3 da Matriz/metabolismo , Camundongos , Poli I-C/farmacologia , Proteína 2 Glutamina gama-Glutamiltransferase , RNA de Cadeia Dupla/metabolismo , Receptor 3 Toll-Like/genética , Receptor 3 Toll-Like/metabolismo
8.
Exp Lung Res ; 47(10): 465-475, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34818962

RESUMO

Transforming growth factor beta 1 (TGF-ß1) induces pulmonary fibrosis by enhancing epithelial apoptosis and affects the enzymatic activity of transglutaminase 2 (TG2). The aim of this study was to determine the role of TG2 in TGF-ß1-induced lung remodeling and alveolar macrophage modulation. We characterized the in vivo effects of TGF-ß1 and TG2 on lung inflammation, fibrosis, and macrophage activity using transgenic C57BL/6 mice with wild and null TG2 loci. The effect of TG2 inhibition on in vitro TGF-ß1-stimulated alveolar macrophages was assessed through mRNA analysis. TG2 was remarkably upregulated in the lungs of TGF-ß1 transgenic (TGF-ß1 Tg) mice, especially in alveolar macrophages and epithelial cells. In the absence of TG2, TGF-ß1-induced inflammation was suppressed, decreasing the number of macrophages in the bronchoalveolar lavage fluid. In addition, the alveolar destruction and peribronchial fibrosis induced by TGF-ß1 overexpression were significantly reduced, which correlated with decreases in the expression of fibroblast growth factor and matrix metallopeptidase 12, respectively. However, TG2 deficiency did not compromise the phagocytic activity of alveolar macrophages in TGF-ß1 Tg mice. At the same time, TG2 contributed to the regulation of TGF-ß1-induced macrophage activation. Inhibition of TG2 did not affect the TGF-ß1-induced expression of CD86, an M1 marker, in macrophages, but it did reverse the TGF-ß1-induced expression of CD206. This result suggests that TG2 mediates TGF-ß1-induced M2-like polarization but does not contribute to TGF-ß1-induced M1 polarization. In conclusion, TG2 regulates macrophage modulation and plays an important role in TGF-ß1-induced lung inflammation, destruction, and fibrosis.


Assuntos
Macrófagos Alveolares , Pneumonia , Proteína 2 Glutamina gama-Glutamiltransferase/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Animais , Pulmão , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
9.
Skin Res Technol ; 27(4): 599-606, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33369781

RESUMO

BACKGROUND: The influence of various environmental factors on skin properties is well known. However, there is a lack of research into the effect of quarantine masks on skin properties, even though the use of masks has significantly increased after the COVID-19 outbreak. Therefore, this study aimed to investigate the influence of mask use on skin properties. MATERIALS AND METHODS: Twenty subjects were enrolled in this study. The subjects used approved quarantine masks for 6 hours a day for 2 weeks. We measured eight skin biophysical parameters: temperature, redness, pore volume, texture, elasticity, trans-epidermal water loss (TEWL), sebum content, and pH, and evaluated acne lesions before and after using quarantine masks. The evaluation was performed on the mask-wearing area of the face. RESULTS: Skin temperature, redness, and TEWL increased significantly after a 6-hour mask use, while the sebum content increased marginally. Skin elasticity was reduced by the use of masks over 1 and 2 weeks, whereas the pore volume and the number of acne lesions increased after a 2-week mask use. The skin changes caused by mask use showed sex-based differences in the skin elasticity (after 6 hours), redness, and roughness (after 2 weeks). CONCLUSIONS: The use of quarantine masks causes a change in the skin temperature, redness, and TEWL in the short term and in skin elasticity, pores, and acne in the long term. This study revealed that prolonged mask use could have negative effects on the skin.


Assuntos
COVID-19 , Pandemias , Humanos , Máscaras , Quarentena , SARS-CoV-2
10.
Skin Res Technol ; 27(6): 1017-1022, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34080757

RESUMO

BACKGROUND: Reduction in skin elasticity due to aging causes skin sagging and wrinkles. Although there are various objective and reliable techniques for measuring skin elasticity, it is difficult to obtain a visual representation of skin elasticity with them. Therefore, we developed a novel device, the Swing anglemeter, and analyzed its effectiveness for measuring skin elasticity of the cheek. MATERIALS AND METHODS: Forty-five healthy Korean women (age, 23-60 years) participated. The Swing anglemeter works by dropping a rubber ball on a subject's cheek, which draws a curve as it collides with the cheek. After recording the movement of the ball using the slow-motion function on a mobile phone, we defined the maximum angle at which the ball bounces off the skin as the elastic angle, using frame-by-frame video analysis. Changes in the elastic angle were assessed according to age, and correlation with the Ballistometer® results (Dia-stron Ltd., Andover, UK) was analyzed for validation. RESULTS: Elastic angles differed significantly (P < .001) according to age. A negative correlation was found between the elastic angle and age (r = -.799, P < .001). Compared with the Ballistometer® measurements, the elastic angle was negatively correlated with alpha (r = -.570, P < .001); it was positively correlated with the mean coefficient of restitution and area (r = .602, P < .001 and r = .535, P < .001, respectively). CONCLUSION: The elastic angle is a useful parameter for reflecting skin elasticity, both quantitatively and visually. Our method can help subjects understand their skin elasticity status. Therefore, we expect the device will be utilized in various fields within the cosmetic industry.


Assuntos
Anormalidades da Pele , Envelhecimento da Pele , Adulto , Envelhecimento , Bochecha/diagnóstico por imagem , Elasticidade , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem
11.
Int J Cosmet Sci ; 43(3): 275-282, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33544395

RESUMO

OBJECTIVE: Lip skin dryness and chapping are major concerns related to lip skin care in many populations. The distinctive features of lip skin, such as the low water-holding capacity and weak skin barrier, are strongly associated with these problems; however, few studies have examined lip skin characteristics and the mechanisms underlying these issues. This study was conducted to identify the biophysical properties of dry lip skin and molecular targets affecting lip skin physiology. METHODS: Skin hydration, transepidermal water loss and lip skin scaling were evaluated in 40 female subjects. Skin scaling was assessed as a percentage area divided into five categories (G0, G1, G2, G3 and G4) according to the thickness level of tape-stripped corneocytes. The activities and amounts of proteases, cathepsin D and bleomycin hydrolase were measured as markers for the desquamation process and skin hydration, respectively. RESULTS: Skin hydration showed a significantly positive correlation with the percentage area of evenly thin corneocytes (G0) and negative correlations with the percentage areas of slightly thick to severely thick corneocytes (G1-G4). The corneocyte unevenness ratio (CUR) was calculated by dividing the sum of the G1, G2, G3 and G4 values with the G0 value. The CUR was significantly negatively correlated with skin hydration, suggesting that CUR is a new parameter representing the severity of lip scaling. Subjects with lower hydration and higher CUR had higher bleomycin hydrolase activity and lower cathepsin D activity, respectively, than subjects with higher hydration and lower CUR. CONCLUSION: Our study revealed a correlation between lip skin hydration and severity of lip scaling and verified the association of protease activity with the hydration and chapping state of lip skin. These observations provide a basis for further studies of the persistent problem of lip skin dryness and chapping.


OBJECTIF: La sécheresse et la gerçure de la peau des lèvres sont des préoccupations majeures liées aux soins de la peau des lèvres chez de nombreuses populations. Les caractéristiques distinctives de la peau des lèvres, telles que la faible capacité de rétention d'eau et la faible barrière cutanée, sont fortement associées à ces problèmes ; cependant, peu d'études ont examiné les caractéristiques de la peau des lèvres et les mécanismes sous-jacents à ces problèmes. Cette étude a été menée dans le but d'identifier les propriétés biophysiques de la peau sèche des lèvres et les cibles moléculaires affectant la physiologie de la peau des lèvres. MÉTHODES: L'hydratation cutanée, la perte d'eau transépidermique et la desquamation de la peau des lèvres ont été évaluées chez 40 sujets de sexe féminin. La desquamation cutanée a été évaluée en tant que pourcentage de surface, divisée en cinq catégories (G0, G1, G2, G3 et G4) en fonction du niveau d'épaisseur des cornocytes sur la bande adhésive. Les activités et quantités des protéases, de la cathepsine D et de la bléomycine hydrolase ont été mesurées comme marqueurs du processus de desquamation et de l'hydratation cutanée, respectivement. RÉSULTATS: L'hydratation cutanée a montré une corrélation significativement positive avec le pourcentage de surface avec cornocytes uniformément minces (G0), et des corrélations négatives avec les pourcentages de surface avec cornocytes légèrement épais à très épais (G1-G4). Le rapport d'irrégularité des cornocytes (Corneocyte Unevenness Ratio, CUR) a été calculé en divisant la somme des valeurs de G1, G2, G3 et G4 par la valeur de G0. Le CUR était significativement corrélé négativement avec l'hydratation de la peau, ce qui suggère que le CUR est un nouveau paramètre représentant la gravité de la desquamation des lèvres. Les sujets avec une hydratation plus faible et un CUR plus élevé présentaient une activité de la bléomycine hydrolase plus élevée et une activité de la cathepsine D plus faible, respectivement, par rapport aux sujets avec une hydratation plus élevée et un CUR plus faible. CONCLUSION: Notre étude a révélé une corrélation entre l'hydratation de la peau des lèvres et la gravité de la desquamation des lèvres, et a vérifié l'association de l'activité de la protéase avec l'état d'hydratation et de gerçure de la peau des lèvres. Ces observations fournissent une base pour d'autres études sur le problème persistant de la sécheresse et de la gerçure de la peau des lèvres.


Assuntos
Queilite/patologia , Lábio/patologia , Adulto , Fenômenos Biofísicos , Queilite/metabolismo , Feminino , Humanos , Lábio/enzimologia , Lábio/metabolismo , Peptídeo Hidrolases/metabolismo , Índice de Gravidade de Doença , Água/metabolismo
12.
J Med Internet Res ; 22(5): e16443, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32348254

RESUMO

BACKGROUND: Continuous photoplethysmography (PPG) monitoring with a wearable device may aid the early detection of atrial fibrillation (AF). OBJECTIVE: We aimed to evaluate the diagnostic performance of a ring-type wearable device (CardioTracker, CART), which can detect AF using deep learning analysis of PPG signals. METHODS: Patients with persistent AF who underwent cardioversion were recruited prospectively. We recorded PPG signals at the finger with CART and a conventional pulse oximeter before and after cardioversion over a period of 15 min (each instrument). Cardiologists validated the PPG rhythms with simultaneous single-lead electrocardiography. The PPG data were transmitted to a smartphone wirelessly and analyzed with a deep learning algorithm. We also validated the deep learning algorithm in 20 healthy subjects with sinus rhythm (SR). RESULTS: In 100 study participants, CART generated a total of 13,038 30-s PPG samples (5850 for SR and 7188 for AF). Using the deep learning algorithm, the diagnostic accuracy, sensitivity, specificity, positive-predictive value, and negative-predictive value were 96.9%, 99.0%, 94.3%, 95.6%, and 98.7%, respectively. Although the diagnostic accuracy decreased with shorter sample lengths, the accuracy was maintained at 94.7% with 10-s measurements. For SR, the specificity decreased with higher variability of peak-to-peak intervals. However, for AF, CART maintained consistent sensitivity regardless of variability. Pulse rates had a lower impact on sensitivity than on specificity. The performance of CART was comparable to that of the conventional device when using a proper threshold. External validation showed that 94.99% (16,529/17,400) of the PPG samples from the control group were correctly identified with SR. CONCLUSIONS: A ring-type wearable device with deep learning analysis of PPG signals could accurately diagnose AF without relying on electrocardiography. With this device, continuous monitoring for AF may be promising in high-risk populations. TRIAL REGISTRATION: ClinicalTrials.gov NCT04023188; https://clinicaltrials.gov/ct2/show/NCT04023188.


Assuntos
Fibrilação Atrial/diagnóstico , Aprendizado Profundo/normas , Fotopletismografia/métodos , Dispositivos Eletrônicos Vestíveis/normas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudo de Prova de Conceito , Estudos Prospectivos
13.
Arthroscopy ; 36(4): 971-980, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31805388

RESUMO

PURPOSE: To assess the mid-term safety and efficacy of an intratendinous injection of autologous adipose tissue-derived mesenchymal stem cells (AD MSCs) for rotator cuff disease at 2-year follow-up. METHODS: The first part of the study consisted of 3 dose-escalation groups, with 3 patients each, for the evaluation of safety: low-dose (1.0 × 107 cells), mid-dose (5.0 × 107), and high-dose (1.0 × 108) groups. For the second part, we planned to include 9 patients receiving the high dose for the evaluation of exploratory efficacy. Clinical outcomes were assessed according to pain, range of motion, muscle strength, functional scores, overall satisfaction and function, and presence of failure. Structural outcomes included changes in volume of tendon defects measured using magnetic resonance imaging. RESULTS: This study enrolled 19 patients (9 for the first part and 10 for the second part) with partial-thickness rotator cuff tears. There were no treatment-related adverse events at minimum 2-year follow-up. Intratendinous injection of AD MSCs reduced shoulder pain by approximately 90% at 1 and 2 years in the mid- and high-dose groups. The strength of the supraspinatus, infraspinatus, and teres minor significantly increased by greater than 50% at 2 years in the high-dose group. Shoulder function measured with 6 commonly used scores improved for up to 2 years in all dose groups. Structural outcomes evaluated with magnetic resonance imaging showed that the volume of bursal-sided defects in the high-dose group nearly disappeared at 1 year and did not recur at up to 2 years. No failures-defined as the performance of any kind of shoulder surgery or return of the Shoulder Pain and Disability Index score to the preinjection level-occurred during follow-up. CONCLUSIONS: This study showed continued safety and efficacy of an intratendinous injection of AD MSCs for the treatment of partial-thickness rotator cuff tears over a 2-year period through regeneration of tendon defects. LEVEL OF EVIDENCE: Level III, retrospective comparative study.


Assuntos
Transplante de Células-Tronco Mesenquimais , Lesões do Manguito Rotador/terapia , Idoso , Feminino , Seguimentos , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Força Muscular/fisiologia , Regeneração , Estudos Retrospectivos , Dor de Ombro/terapia
14.
Int J Mol Sci ; 21(3)2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31991788

RESUMO

Transglutaminase 2 (TG2) is a Ca2+-dependent enzyme, which regulates various cellular processes by catalyzing protein crosslinking or polyamination. Intracellular TG2 is activated and inhibited by Ca2+ and GTP binding, respectively. Although aberrant TG2 activation has been implicated in the pathogenesis of diverse diseases, including cancer and degenerative and fibrotic diseases, the structural basis for the regulation of TG2 by Ca2+ and GTP binding is not fully understood. Here, we produced and analyzed a Ca2+-containing TG2 crystal, and identified two glutamate residues, E437 and E539, as Ca2+-binding sites. The enzymatic analysis of the mutants revealed that Ca2+ binding to these sites is required for the transamidase activity of TG2. Interestingly, we found that magnesium (Mg2+) competitively binds to the E437 and E539 residues. The Mg2+ binding to these allosteric sites enhances the GTP binding/hydrolysis activity but inhibits transamidase activity. Furthermore, HEK293 cells transfected with mutant TG2 exhibited higher transamidase activity than cells with wild-type TG2. Cells with wild-type TG2 showed an increase in transamidase activity under Mg2+-depleted conditions, whereas cells with mutant TG2 were unaffected. These results indicate that E437 and E539 are Ca2+-binding sites contributing to the reciprocal regulation of transamidase and GTP binding/hydrolysis activities of TG2 through competitive Mg2+ binding.


Assuntos
Aminoaciltransferases/metabolismo , Sítios de Ligação , Cálcio/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Guanosina Trifosfato/metabolismo , Magnésio/metabolismo , Transglutaminases/metabolismo , Sequência de Aminoácidos , Aminoaciltransferases/química , Ligação Competitiva , Cálcio/química , Ativação Enzimática , Proteínas de Ligação ao GTP/química , Guanosina Trifosfato/química , Humanos , Hidrólise , Magnésio/química , Modelos Biológicos , Conformação Molecular , Ligação Proteica , Proteína 2 Glutamina gama-Glutamiltransferase , Relação Estrutura-Atividade , Transglutaminases/química
15.
Molecules ; 25(24)2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33339214

RESUMO

Previously, we demonstrated that a 5% ethanol extract of unripe Rubus coreanus (5-uRCK) and ellagic acid has hypocholesterolemic and antiobesity activity, at least partially mediated by the downregulation of adipogenic and lipogenic gene expression in high-fat diet (HFD)-fed animals. The present study investigated the thermogenic and lipolytic antiobesity effects of 5-uRCK and ellagic acid in HFD-induced obese C57BL/6 mice and explored its mechanism of action. Mice fed an HFD received 5-uRCK or ellagic acid as a post-treatment or pretreatment. Both post-treated and pretreated mice showed significant reductions in body weight and adipose tissue mass compared to the HFD-fed mice. The protein levels of lipolysis-associated proteins, such as adipose triglyceride lipase (ATGL), phosphorylated hormone-sensitive lipase (p-HSL), and perilipin1 (PLIN1), were significantly increased in both the 5-uRCK- and ellagic acid-treated mouse epididymal white adipose tissue (eWAT). Additionally, thermogenesis-associated proteins, such as peroxisome proliferator-activated receptor α (PPARα), carnitine palmitoyl transferase-1 (CPT1), uncoupling protein 1 (UCP1), and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC1α), in inguinal white adipose tissue (ingWAT) were clearly increased in both the 5-uRCK- and ellagic acid-treated mice compared to HFD-fed mice. These results suggest that 5-uRCK and ellagic acid are effective for suppressing body weight gain and enhancing the lipid profile.


Assuntos
Ácido Elágico/química , Lipólise/efeitos dos fármacos , Extratos Vegetais/farmacologia , Rubus/química , Termogênese/efeitos dos fármacos , Adipogenia/genética , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/patologia , Animais , Biomarcadores/metabolismo , Peso Corporal/efeitos dos fármacos , Dieta Hiperlipídica , Regulação para Baixo/efeitos dos fármacos , Ácido Elágico/administração & dosagem , Ácido Elágico/isolamento & purificação , Ácido Elágico/farmacologia , Lipogênese/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/tratamento farmacológico , Obesidade/veterinária , PPAR alfa/genética , PPAR alfa/metabolismo , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Rubus/metabolismo , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
16.
Stem Cells ; 36(9): 1441-1450, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29790618

RESUMO

Despite relatively good results of current symptomatic treatments for rotator cuff disease, there has been an unmet need for fundamental treatments to halt or reverse the progress of disease. The purpose of this study was to assess the safety and efficacy of intratendinous injection of autologous adipose tissue-derived mesenchymal stem cells (AD MSCs) in patients with rotator cuff disease. The first part of the study consists of three dose-escalation cohorts; the low- (1.0 × 107 cells), mid- (5.0 × 107 ), and high-dose (1.0 × 108 ) groups with three patients each for the evaluation of the safety and tolerability. The second part included nine patients receiving the high-dose for the evaluation of the exploratory efficacy. The primary outcomes were the safety and the shoulder pain and disability index (SPADI). Secondary outcomes included clinical, radiological, and arthroscopic evaluations. Twenty patients were enrolled in the study, and two patients were excluded. Intratendinous injection of AD MSCs was not associated with adverse events. It significantly decreased the SPADI scores by 80% and 77% in the mid- and high-dose groups, respectively. Shoulder pain was significantly alleviated by 71% in the high-dose group. Magnetic resonance imaging examination showed that volume of the bursal-side defect significantly decreased by 90% in the high-dose group. Arthroscopic examination demonstrated that volume of the articular- and bursal-side defects decreased by 83% and 90% in the mid- and high-dose groups, respectively. Intratendinous injection of autologous AD MSCs in patient with a partial-thickness rotator cuff tear did not cause adverse events, but improved shoulder function, and relieved pain through regeneration of rotator cuff tendon. Stem Cells 2018;36:1441-1450.


Assuntos
Tecido Adiposo/transplante , Células-Tronco Mesenquimais/metabolismo , Lesões do Manguito Rotador/terapia , Transplante Autólogo/métodos , Adulto , Feminino , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Lesões do Manguito Rotador/patologia , Resultado do Tratamento
17.
J Youth Adolesc ; 48(12): 2333-2342, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31327099

RESUMO

With the increase in social concern regarding pathological gaming among adolescents, the WHO (World Health Organization) included "gaming disorder" in the International Classification of Disorders, 11th version (ICD-11). However, little longitudinal research has been conducted examining social influences on pathological gaming, particularly in Asian countries (e.g., South Korea, China). With 4-year panel data from young adolescents (N = 968, 50.7% girls; Mage = 13.3 years) in South Korea, this study examined the effects of cultural environmental factors (parents' excessive interference, communication with parents, and friends' and teachers' support) on pathological gaming through academic stress and self-control. The results showed the critical role of academic stress and self-control in the effects of environmental factors on pathological gaming. Parents' excessive interference increased the degree to which youth experienced academic stress while the degree of communication with parents decreased this stress. Increased academic stress damaged self-control, which finally increased the degree of pathological gaming. Self-control affected the degree of pathological gaming stronger than gaming time did. The theoretical and practical implications from the study findings are discussed.


Assuntos
Comportamento do Adolescente/psicologia , Comportamento Aditivo/psicologia , Autocontrole , Jogos de Vídeo/psicologia , Adolescente , Transtornos Disruptivos, de Controle do Impulso e da Conduta/psicologia , Feminino , Humanos , Internet , Estudos Longitudinais , Masculino , República da Coreia
18.
J Am Acad Dermatol ; 79(5): 843-852, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29792909

RESUMO

BACKGROUND: Little is known regarding oncoproteins other than platelet-derived growth factor subunit B in dermatofibrosarcoma protuberans (DFSP). Moreover, the risk factors for worse prognosis are controversial. OBJECTIVE: We sought to determine the clinicopathologic features and key factors for adverse outcome in DFSP, including the implication of expression of protein kinase B (Akt)/mammalian target of rapamycin (mTOR), signal transducer and activator of transcription 3 (STAT3), extracellular signal regulated kinase (ERK), cyclin D1, and programmed death ligand 1 (PD-L1). METHODS: Clinicopathologic and immunohistochemical analyses were performed for 44 DFSPs having wide local excision and 92 dermatofibromas as controls. RESULTS: Compared with the 35 nonrecurrent DFSPs, the 9 recurrent DFSPs exhibited larger tumor size, deeper invasion beyond the subcutis, and more diverse histologic subtype. The fibrosarcomatous subtype revealed frequent mitotic figures and a high cyclin D1-positive index. The 2 metastatic DFSPs (1 each of the fibrosarcomatous and myxoid subtypes) demonstrated 4 and 11 instances of local recurrence, respectively, as well as larger tumor size, deeper invasion beyond the subcutis, and high expression of cyclin D1. Expression of Akt/mTOR, STAT3, ERK, and PD-L1 ranged from none or low in the primary skin lesions to high in the corresponding metastatic sites. Akt/mTOR and ERK were expressed more frequently in DFSP than in dermatofibroma. LIMITATIONS: Lack of information on patients before hospital evaluation. CONCLUSION: Complex factors beyond fibrosarcomatous subtype may portend local recurrence or metastasis. Akt/mTOR, STAT3, ERK, and PD-L1 may be associated with development and/or progression of DFSP.


Assuntos
Biomarcadores Tumorais/genética , Dermatofibrossarcoma/genética , Dermatofibrossarcoma/patologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Adulto , Idoso , Antígeno B7-H1/genética , Biópsia por Agulha , Ciclina D1/genética , Ciclina D1/metabolismo , Bases de Dados Factuais , Dermatofibrossarcoma/mortalidade , Dermatofibrossarcoma/cirurgia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Sistema de Sinalização das MAP Quinases/genética , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/mortalidade , Estadiamento de Neoplasias , Proteína Oncogênica v-akt/genética , Proteína Oncogênica v-akt/metabolismo , Prognóstico , República da Coreia , Medição de Risco , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/cirurgia , Análise de Sobrevida , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
19.
Mol Cancer ; 16(1): 10, 2017 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-28137309

RESUMO

Radiation therapy is one of the major tools of cancer treatment, and is widely used for a variety of malignant tumours. Radiotherapy causes DNA damage directly by ionization or indirectly via the generation of reactive oxygen species (ROS), thereby destroying cancer cells. However, ionizing radiation (IR) paradoxically promotes metastasis and invasion of cancer cells by inducing the epithelial-mesenchymal transition (EMT). Metastasis is a major obstacle to successful cancer therapy, and is closely linked to the rates of morbidity and mortality of many cancers. ROS have been shown to play important roles in mediating the biological effects of IR. ROS have been implicated in IR-induced EMT, via activation of several EMT transcription factors-including Snail, HIF-1, ZEB1, and STAT3-that are activated by signalling pathways, including those of TGF-ß, Wnt, Hedgehog, Notch, G-CSF, EGFR/PI3K/Akt, and MAPK. Cancer cells that undergo EMT have been shown to acquire stemness and undergo metabolic changes, although these points are debated. IR is known to induce cancer stem cell (CSC) properties, including dedifferentiation and self-renewal, and to promote oncogenic metabolism by activating these EMT-inducing pathways. Much accumulated evidence has shown that metabolic alterations in cancer cells are closely associated with the EMT and CSC phenotypes; specifically, the IR-induced oncogenic metabolism seems to be required for acquisition of the EMT and CSC phenotypes. IR can also elicit various changes in the tumour microenvironment (TME) that may affect invasion and metastasis. EMT, CSC, and oncogenic metabolism are involved in radioresistance; targeting them may improve the efficacy of radiotherapy, preventing tumour recurrence and metastasis. This study focuses on the molecular mechanisms of IR-induced EMT, CSCs, oncogenic metabolism, and alterations in the TME. We discuss how IR-induced EMT/CSC/oncogenic metabolism may promote resistance to radiotherapy; we also review efforts to develop therapeutic approaches to eliminate these IR-induced adverse effects.


Assuntos
Transição Epitelial-Mesenquimal , Células-Tronco Neoplásicas/efeitos da radiação , Tolerância a Radiação , Desdiferenciação Celular , Humanos , Metástase Neoplásica , Neoplasias , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Fenótipo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
20.
Biochim Biophys Acta ; 1853(3): 619-31, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25549939

RESUMO

Cystamine and its reduced form cysteamine showed protective effects in various models of neurodegenerative disease, including Huntington's disease and Parkinson's disease. Other lines of evidence demonstrated the cytotoxic effect of cysteamine on duodenal mucosa leading to ulcer development. However, the mechanism for cystamine cytotoxicity remains poorly understood. Here, we report a new pathway in which cystamine induces apoptosis by targeting apoptosis-inducing factor (AIF). By screening of various cell lines, we observed that cystamine and cysteamine induce cell death in a cell type-specific manner. Comparison between cystamine-sensitive and cystamine-resistant cell lines revealed that cystamine cytotoxicity is not associated with unfolded protein response, reactive oxygen species generation and transglutaminase or caspase activity; rather, it is associated with the ability of cystamine to trigger AIF nuclear translocation. In cystamine-sensitive cells, cystamine suppresses the levels of intracellular glutathione by inhibiting γ-glutamylcysteine synthetase expression that triggers AIF translocation. Conversely, glutathione supplementation completely prevents cystamine-induced AIF translocation and apoptosis. In rats, cysteamine administration induces glutathione depletion and AIF translocation leading to apoptosis of duodenal epithelium. These results indicate that AIF translocation through glutathione depletion is the molecular mechanism of cystamine toxicity, and provide important implications for cystamine in the neurodegenerative disease therapeutics as well as in the regulation of AIF-mediated cell death.


Assuntos
Fator de Indução de Apoptose/fisiologia , Apoptose/efeitos dos fármacos , Cistamina/farmacologia , Glutationa/metabolismo , Animais , Apoptose/genética , Úlcera Duodenal/metabolismo , Úlcera Duodenal/patologia , Feminino , Células HeLa , Humanos , Células MCF-7 , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Células Tumorais Cultivadas , Regulação para Cima/efeitos dos fármacos
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