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1.
Cell ; 148(5): 1051-64, 2012 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-22385968

RESUMEN

How extrinsic stimuli and intrinsic factors interact to regulate continuous neurogenesis in the postnatal mammalian brain is unknown. Here we show that regulation of dendritic development of newborn neurons by Disrupted-in-Schizophrenia 1 (DISC1) during adult hippocampal neurogenesis requires neurotransmitter GABA-induced, NKCC1-dependent depolarization through a convergence onto the AKT-mTOR pathway. In contrast, DISC1 fails to modulate early-postnatal hippocampal neurogenesis when conversion of GABA-induced depolarization to hyperpolarization is accelerated. Extending the period of GABA-induced depolarization or maternal deprivation stress restores DISC1-dependent dendritic regulation through mTOR pathway during early-postnatal hippocampal neurogenesis. Furthermore, DISC1 and NKCC1 interact epistatically to affect risk for schizophrenia in two independent case control studies. Our study uncovers an interplay between intrinsic DISC1 and extrinsic GABA signaling, two schizophrenia susceptibility pathways, in controlling neurogenesis and suggests critical roles of developmental tempo and experience in manifesting the impact of susceptibility genes on neuronal development and risk for mental disorders.


Asunto(s)
Proteínas del Tejido Nervioso/metabolismo , Neurogénesis , Esquizofrenia/metabolismo , Transducción de Señal , Ácido gamma-Aminobutírico/metabolismo , Animales , Dendritas/metabolismo , Susceptibilidad a Enfermedades , Femenino , Ratones , Ratones Endogámicos C57BL , Proteínas del Tejido Nervioso/genética , Esquizofrenia/genética , Análisis de la Célula Individual , Simportadores de Cloruro de Sodio-Potasio/genética , Simportadores de Cloruro de Sodio-Potasio/metabolismo , Miembro 2 de la Familia de Transportadores de Soluto 12
2.
Nature ; 582(7813): 511-514, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32581381

RESUMEN

Decrease in processing speed due to increased resistance and capacitance delay is a major obstacle for the down-scaling of electronics1-3. Minimizing the dimensions of interconnects (metal wires that connect different electronic components on a chip) is crucial for the miniaturization of devices. Interconnects are isolated from each other by non-conducting (dielectric) layers. So far, research has mostly focused on decreasing the resistance of scaled interconnects because integration of dielectrics using low-temperature deposition processes compatible with complementary metal-oxide-semiconductors is technically challenging. Interconnect isolation materials must have low relative dielectric constants (κ values), serve as diffusion barriers against the migration of metal into semiconductors, and be thermally, chemically and mechanically stable. Specifically, the International Roadmap for Devices and Systems recommends4 the development of dielectrics with κ values of less than 2 by 2028. Existing low-κ materials (such as silicon oxide derivatives, organic compounds and aerogels) have κ values greater than 2 and poor thermo-mechanical properties5. Here we report three-nanometre-thick amorphous boron nitride films with ultralow κ values of 1.78 and 1.16 (close to that of air, κ = 1) at operation frequencies of 100 kilohertz and 1 megahertz, respectively. The films are mechanically and electrically robust, with a breakdown strength of 7.3 megavolts per centimetre, which exceeds requirements. Cross-sectional imaging reveals that amorphous boron nitride prevents the diffusion of cobalt atoms into silicon under very harsh conditions, in contrast to reference barriers. Our results demonstrate that amorphous boron nitride has excellent low-κ dielectric characteristics for high-performance electronics.

3.
Immunology ; 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38778445

RESUMEN

Cytokines of the common-γ receptor chain (γc) family are crucial for T-cell differentiation and dysregulation of γc cytokine pathways is involved in the pathogenesis of autoimmune diseases. There is increasing evidence that the availability of the γc receptor (CD132) for the associated receptor chains has implications for T-cell functions. Here we studied the influence of differential γc expression on the expression of the IL-2Rα (CD25), the IL-7Rα (CD127) and the differentiation of activated naïve T cells. We fine-tuned the regulation of γc expression in human primary naïve T cells by lentiviral transduction using small hairpin (sh)RNAs and γc cDNA. Differential γc levels were then analysed for effects on T-cell phenotype and function after activation. Differential γc expression markedly affected IL-2Rα and IL-7Rα expression on activated naïve T cells. High γc expression (γc-high) induced significantly higher expression of IL-2Rα and re-expression of IL-7Rα after activation. Inhibition of γc caused lower IL-2Rα/IL-7Rα expression and impaired proliferation of activated naïve T cells. In contrast, γc-high T cells secreted significantly higher concentrations of effector cytokines (i.e., IFN-γ, IL-6) and showed higher cytokine-receptor induced STAT5 phosphorylation during initial stages as well as persistently higher pSTAT1 and pSTAT3 levels after activation. Finally, accelerated transition towards a CD45RO expressing effector/memory phenotype was seen especially for CD4+ γc-high naïve T cells. These results suggested that high expression of γc promotes expression of IL-2Rα and IL-7Rα on activated naïve T cells with significant effects on differentiation and effector cytokine expression.

4.
J Cell Biochem ; 125(2): e30518, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38224182

RESUMEN

Excessive bone-resorbing osteoclast activity during bone remodeling is a major feature of bone diseases, such as osteoporosis. Therefore, the inhibition of osteoclast formation and bone resorption can be an effective therapeutic target for various bone diseases. Gryllus biomaculatus (GB) has recently been approved as an alternative food source because of its high nutritional value and environmental sustainability. Traditionally, GB has been known to have various pharmacological properties, including antipyretic and blood pressure-lowering activity, and it has recently been reported to have various biological activities, including protective effects against inflammation, oxidative stress, insulin resistance, and alcohol-induced liver injury. However, the effect of GB on osteoclast differentiation and bone metabolism has not yet been demonstrated. In this study, we confirmed the inhibitory effect of GB extract (GBE) on the receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast formation. To determine the effect of GBE on RANKL-induced osteoclast differentiation and function, we performed TRAP and F-actin staining, as well as a bone-resorbing assay. The intracellular mechanisms of GBE responsible for the regulation of osteoclastogenesis were revealed by Western blot analysis and quantitative real-time polymerase chain reaction. We investigated the relationship between GBE and expression of osteoclast-specific molecules to further elucidate the underlying mechanisms. It was found that GBE significantly suppressed osteoclastogenesis by decreasing the phosphorylation of Akt, p38, JNK, and ERK, as well as Btk-PLCγ2 signaling, in pathways involved in early osteoclastogenesis as well as through the subsequent suppression of c-Fos, NFATc1, and osteoclastogenesis-specific marker genes. Additionally, GBE inhibited the formation of F-actin ring-positive osteoclasts and bone resorption activity of mature osteoclasts. Our findings suggest that GBE is a potential functional food and therapeutic candidate for bone diseases involving osteoclasts.


Asunto(s)
Resorción Ósea , Osteoclastos , Ligando RANK , Humanos , Actinas/metabolismo , Resorción Ósea/tratamiento farmacológico , Diferenciación Celular , Ligandos , FN-kappa B/metabolismo , Factores de Transcripción NFATC/metabolismo , Osteoclastos/metabolismo , Ligando RANK/antagonistas & inhibidores , Ligando RANK/metabolismo
5.
Cancer Sci ; 113(1): 145-155, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34714604

RESUMEN

To improve the poor survival rate of lung cancer patients, we investigated the role of HDGF-related protein 3 (HRP-3) as a potential biomarker for lung cancer. The expression of endogenous HRP-3 in human lung cancer tissues and xenograft tumor models is indicative of its clinical relevance in lung cancer. Additionally, we demonstrated that HRP-3 directly binds to the E2F1 promoter on chromatin. Interestingly, HRP-3 depletion in A549 cells impedes the binding of HRP-3 to the E2F1 promoter; this in turn hampers the interaction between Histone H3/H4 and HDAC1/2 on the E2F1 promoter, while concomitantly inducing Histone H3/H4 acetylation around the E2F1 promoter. The enhanced Histone H3/H4 acetylation on the E2F1 promoter through HRP-3 depletion increases the transcription level of E2F1. Furthermore, the increased E2F1 transcription levels lead to the enhanced transcription of Cyclin E, known as the E2F1-responsive gene, thus inducing S-phase accumulation. Therefore, our study provides evidence for the utility of HRP-3 as a biomarker for the prognosis and treatment of lung cancer. Furthermore, we delineated the capacity of HRP-3 to regulate the E2F1 transcription level via histone deacetylation.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Ciclina E/metabolismo , Factor de Transcripción E2F1/genética , Histona Desacetilasas/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neoplasias Pulmonares/patología , Células A549 , Animales , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Ratones , Trasplante de Neoplasias , Regiones Promotoras Genéticas , Transducción de Señal
6.
Lung ; 200(6): 697-706, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36264333

RESUMEN

PURPOSE: Blood (EOS-B) and sputum (EOS-S) eosinophil counts may contribute differently to asthma pathogenesis. We compared the impact of the baseline EOS-B and EOS-S levels on lung function, asthma control, and exacerbation in Korean asthma patients. METHODS: Asthma patients with baseline EOS-B (n = 4257) and EOS-S (n = 1049) levels from a multicenter cohort (COREA) were included. Pulmonary function test (%FEV1 predicted), asthma control test (ACT), and asthma exacerbation incidence were followed-up every 3 months for one year. Linear mixed-effect models and survival analyses were used to examine the association between eosinophilic groups defined by EOS-B or EOS-S and outcomes. RESULTS: High eosinophilic groups were associated with a low baseline value and a high improvement in the %FEV1 predicted and ACT scores over time. The magnitude of group difference in %FEV1 predicted was twofold higher in the EOS-S versus EOS-B classification [mean and 95% CI: 4.7 (0.6-8.8) versus 2.0 (0.2-3.7) for the baseline value and - 1.5 (- 2.3 to - 0.8) versus - 0.8(- 1.1 to -0.4) for the slope of change], whereas it was identical in ACT score. The magnitude of the impact increased linearly with the elevation of the cut-off level for the EOS-B but remained stable for the EOS-S classification. Patients with an elevation of both their EOS-B and EOS-S showed a higher increment in the %FEV1 predicted and ACT over time. Neither the EOS-B nor EOS-S was associated with asthma exacerbation. CONCLUSION: EOS-S and EOS-B contribute differently to the clinical outcomes and should be taken into account independently to improve asthma care.


Asunto(s)
Asma , Eosinófilos , Humanos , Eosinófilos/patología , Esputo , Pruebas de Función Respiratoria , Recuento de Leucocitos , Pulmón
7.
J Korean Med Sci ; 37(9): e72, 2022 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-35257527

RESUMEN

BACKGROUND: Colorectal polyps are the most common cause of isolated hematochezia in children, which requires a colonoscopy for diagnosis. We aimed to investigate the potential utility of fecal calprotectin (FC) in assessing colorectal polyps detected by colonoscopy among children presenting with isolated hematochezia. METHODS: Pediatric patients of the age of < 18 years who had undergone both colonoscopy and FC tests for isolated hematochezia from June 2016 to May 2020 were included in the present multicenter, retrospective, cross-sectional study. Comparative analysis was conducted between major causes of isolated hematochezia and FC cut-offs for discriminating colorectal polyps were explored. RESULTS: A total 127 patients were included. Thirty-five patients (27.6%) had colorectal polyps, followed by anal fissure (14.2%), ulcerative colitis (UC; 12.6%), and others. A significant difference in FC levels was observed between patients with colorectal polyps (median, 278.7 mg/kg), anal fissures (median, 42.2 mg/kg), and UC (median, 981 mg/kg) (P < 0.001). According to receiver operating characteristic curve analysis, among patients diagnosed with colorectal polyp or anal fissure, the most accurate FC cut-off for discriminating colorectal polyps from anal fissures on colonoscopy was 225 mg/kg (sensitivity, 59.4%; specificity, 94.4%; positive predictive value [PPV], 95.0%; negative predictive value [NPV], 56.7%; area under the curve [AUC], 0.8; 95% confidence interval [CI], 0.678-0.923; P < 0.001), while among patients diagnosed with colorectal polyp or UC, the most accurate FC cut-off for discriminating colorectal polyps from UC on colonoscopy was 879 mg/kg (sensitivity, 81.2%; specificity, 56.2%; PPV, 78.8%; NPV, 60.0%; AUC, 0.687; 95% CI, 0.521-0.852; P < 0.001). CONCLUSION: FC may assist in assessing the cause of lower gastrointestinal tract bleeding in children who present with isolated hematochezia.


Asunto(s)
Pólipos del Colon/diagnóstico , Heces/química , Hemorragia Gastrointestinal/fisiopatología , Complejo de Antígeno L1 de Leucocito/aislamiento & purificación , Adolescente , Niño , Estudios Transversales , Femenino , Humanos , Masculino , República de Corea , Estudios Retrospectivos
8.
Medicina (Kaunas) ; 58(10)2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36295539

RESUMEN

Background and Objectives: The coronavirus disease 2019 (COVID-19) pandemic has affected medical practice in diverse ways. We aimed to investigate the change in trends of lower gastrointestinal (LGI) endoscopy conducted in children and adolescents after the COVID-19 outbreak in Korea. Material and Methods: This was a multicenter, retrospective study conducted in Korea. We included children and adolescents aged <19 years who had undergone their first LGI endoscopy between 2016 and 2020. We compared clinicodemographic and endoscopic factors between groups divided according to the pre- and postCOVID-19 era in Korea. Results: We included 1307 patients in this study. Colonoscopies, instead of sigmoidoscopies, were conducted in most patients in the postCOVID-19 era compared to those in the preCOVID-19 era (86.9% vs. 78.5%, p = 0.007). The diagnosis of inflammatory bowel disease (IBD) was also significantly higher in the postCOVID-19 era compared to the preCOVID-19 era (47.2% vs. 28.5%, p < 0.001). According to multivariate logistic regression analysis, age at LGI endoscopy, LGI bleeding indication, and IBD diagnosis were independently associated with the use of a colonoscopy over a sigmoidoscopy (odds ratio (OR) 1.19, 95% confidence interval (CI) 1.12−1.27, p < 0.001; OR 0.56, 95% CI 0.37−0.83, p = 0.005; OR 1.80, 95% CI 1.20−2.77, p = 0.006, respectively). Conclusions: The COVID-19 pandemic has changed LGI endoscopy practice trends of pediatric gastroenterologists in Korea, who tended to perform lesser LGI endoscopies compared to previous years while conducting significantly more colonoscopies than sigmoidoscopies in the postCOVID-19 era. Furthermore, these colonoscopies were significantly associated with the diagnosis of IBD, as well as a significant increase in IBD diagnosis in the postCOVID-19 era.


Asunto(s)
COVID-19 , Enfermedades Inflamatorias del Intestino , Niño , Humanos , Adolescente , COVID-19/epidemiología , Pandemias , Estudios Retrospectivos , Endoscopía Gastrointestinal , Enfermedades Inflamatorias del Intestino/complicaciones , República de Corea/epidemiología
9.
Int J Obes (Lond) ; 45(4): 776-786, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33473176

RESUMEN

OBJECTIVE: We investigated the efficacy and safety of liraglutide 3 mg daily in combination with diet and exercise 2, 4, and 6 months after initiation in real-world settings in Korea. METHODS: People first using liraglutide starting in 2018 were recruited from ten sites in Korea. Body weight and body mass index (BMI) were measured after 2, 4, and 6 months and compared with baseline values. RESULTS: The full cohort comprised 769 participants: 672 in the 2-month group, 427 in the 4-month group, and 219 in the 6-month group. The baseline mean ± standard deviation of BMI and body weight were 32.2 ± 5.1 kg/m2, and 87.5 ± 18.8 kg, respectively. Body weight and BMI decreased after initiation of liraglutide treatment: -2.94 kg and -1.08 kg/m2 at 2 months; -4.23 kg and -1.55 kg/m2 at 4 months, and -5.14 kg and -1.89 kg/m2 at 6 months (all P < 0.001). In the 6-month cohort, 52.5% and 18.3% of subjects lost ≥5% and ≥10% of body weight, respectively. After 6 months, systolic and diastolic blood pressure decreased significantly by 3.90 and 1.93 mmHg, respectively. In those with diabetes mellitus, HbA1c and fasting glucose levels decreased significantly by 1.14% and 27.8 mg/dl, respectively. Among all participants, 27.6% experienced adverse effects, including nausea (20.8%), vomiting (5.2%), diarrhoea (2.5%), and skin rash (3.6%). Documented reasons for discontinuation of treatment were lack of effect (4.4%), adverse events (4.3%), and high cost (3.1%). CONCLUSIONS: In real-world settings in Korea, daily treatment with liraglutide 3 mg was associated with clinically meaningful weight loss without serious adverse events.


Asunto(s)
Estilo de Vida , Liraglutida/uso terapéutico , Obesidad/terapia , Pérdida de Peso , Adulto , Presión Sanguínea , Índice de Masa Corporal , Peso Corporal , Ejercicio Físico , Femenino , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Masculino , Persona de Mediana Edad , República de Corea
10.
J Korean Med Sci ; 36(20): e136, 2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-34032029

RESUMEN

BACKGROUND: Sedative upper endoscopy is similar in pediatrics and adults, but it is characteristically more likely to lead to respiratory failure. Although recommended guidelines for pediatric procedural sedation are available within South Korea and internationally, Korean pediatric endoscopists use different drugs, either alone or in combination, in practice. Efforts are being made to minimize the risk of sedation while avoiding procedural challenges. The purpose of this study was to collect and analyze data on the sedation methods used by Korean pediatric endoscopists to help physicians perform pediatric sedative upper endoscopy (PSUE). METHODS: The PSUE procedures performed in 15 Korean pediatric gastrointestinal endoscopic units within a year were analyzed. Drugs used for sedation were grouped according to the method of use, and the depth of sedation was evaluated based on the Ramsay scores. The procedures and their complications were also assessed. RESULTS: In total, 734 patients who underwent PSUE were included. Sedation and monitoring were performed by an anesthesiologist at one of the institutions. The sedative procedures were performed by a pediatric endoscopist at the other 14 institutions. Regarding the number of assistants present during the procedures, 36.6% of procedures had one assistant, 38.8% had 2 assistants, and 24.5% had 3 assistants. The average age of the patients was 11.6 years old. Of the patients, 19.8% had underlying diseases, 10.0% were taking medications such as epilepsy drugs, and 1.0% had snoring or sleep apnea history. The average duration of the procedures was 5.2 minutes. The subjects were divided into 5 groups as follows: 1) midazolam + propofol + ketamine (M + P + K): n = 18, average dose of 0.03 + 2.4 + 0.5 mg/kg; 2) M + P: n = 206, average dose of 0.06 + 2.1 mg/kg; 3) M + K: n = 267, average dose of 0.09 + 0.69 mg/kg; 4) continuous P infusion for 20 minutes: n = 15, average dose of 6.6 mg/kg; 5) M: n = 228, average dose of 0.11 mg/kg. The average Ramsay score for the five groups was 3.7, with significant differences between the groups (P < 0.001). Regarding the adverse effects, desaturation and increased oxygen supply were most prevalent in the M + K group. Decreases and increases in blood pressure were most prevalent in the M + P + K group, and bag-mask ventilation was most used in the M + K group. There were no reported incidents of intubation or cardiopulmonary resuscitation. A decrease in oxygen saturation was observed in 37 of 734 patients, and it significantly increased in young patients (P = 0.001) and when ketamine was used (P = 0.014). Oxygen saturation was also correlated with dosage (P = 0.037). The use of ketamine (P < 0.001) and propofol (P < 0.001) were identified as factors affecting the Ramsay score in the logistic regression analysis. CONCLUSION: Although the drug use by Korean pediatric endoscopists followed the recommended guidelines to an extent, it was apparent that they combined the drugs or reduced the doses depending on the patient characteristics to reduce the likelihood of respiratory failure. Inducing deep sedation facilitates comfort during the procedure, but it also leads to a higher risk of complications.


Asunto(s)
Sedación Consciente/normas , Endoscopía Gastrointestinal/métodos , Hipnóticos y Sedantes/administración & dosificación , Pediatría/normas , Adulto , Niño , Preescolar , Femenino , Humanos , Hipnóticos y Sedantes/efectos adversos , Ketamina/administración & dosificación , Ketamina/efectos adversos , Masculino , Midazolam/administración & dosificación , Midazolam/efectos adversos , Pediatría/organización & administración , Propofol/administración & dosificación , Propofol/efectos adversos , República de Corea
11.
Drug Dev Ind Pharm ; 47(5): 685-693, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33866911

RESUMEN

As an active pharmaceutical ingredient, dapagliflozin propanediol monohydrate (D-PD) has been used in the solvated form consisting of dapagliflozin compounded with (S)-propylene glycol and monohydrate at a 1:1:1 ratio. However, dapagliflozin propanediol loses the solvent's reduced lattice structure at slightly higher temperatures. Due to its sensitive solid-state stability, the temperature and humidity are strictly controlled during the production and storage of dapagliflozin. Thus, crystalline molecular complexes containing pharmaceutical salts, solvates, monohydrates, and cocrystals have recently been developed as alternative strategies. This study investigated the dapagliflozin free base (D-FB), D-PD, and dapagliflozin l-proline cocrystals (D-LP). Their solid-state behavior was also evaluated in stress stability studies. The compounds were analyzed using scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), Fourier-transform infrared (FT-IR) spectroscopy, dynamic vapor sorption (DVS), and powder rheology testing. In addition, Carr's index, the Hausner ratio, contact angle, and intrinsic dissolution rate were calculated. Dapagliflozin exhibited distinct physical properties depending upon the differences in solid form and also showed significant differences in solid-state behavior in the stress stability test. In conclusion, D-LP was superior to D-FB or D-PD in physicochemical and mechanical properties.


Asunto(s)
Glucósidos , Compuestos de Bencidrilo , Rastreo Diferencial de Calorimetría , Difracción de Polvo , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
12.
Nano Lett ; 20(9): 6706-6711, 2020 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-32794761

RESUMEN

Failure of a material is an irreversible process since the material loses its original characteristics and properties. The catastrophic brittle failure under tensile stress of nanoporous gold (np-Au) with a bicontinuous open-cell structure makes impossible otherwise attractive applications. Here, we first demonstrate a self-healing process in tensile-fractured np-Au to overcome the limit of fragility via mechanically assisted cold-welding under ambient conditions. The self-healing ability of np-Au in terms of mechanical properties shows strength recovery up to 64.4% and fully recovered elastic modulus compared with initial tensile properties. Topological parameters obtained by three-dimensional reconstruction of self-healed np-Au clarify the strength, elastic modulus, and strain distribution. The self-healing process in np-Au is attributed to surface diffusion expedited by local compressive stress in the ultrasmall dimension of ligaments formed by ductile failures of individual ligaments.

13.
Molecules ; 26(9)2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-34062884

RESUMEN

Osteoporosis is a systemic metabolic bone disorder that is caused by an imbalance in the functions of osteoclasts and osteoblasts and is characterized by excessive bone resorption by osteoclasts. Targeting osteoclast differentiation and bone resorption is considered a good fundamental solution for overcoming bone diseases. ß-boswellic acid (ßBA) is a natural compound found in Boswellia serrata, which is an active ingredient with anti-inflammatory, anti-rheumatic, and anti-cancer effects. Here, we explored the anti-resorptive effect of ßBA on osteoclastogenesis. ßBA significantly inhibited the formation of tartrate-resistant acid phosphatase-positive osteoclasts induced by receptor activator of nuclear factor-B ligand (RANKL) and suppressed bone resorption without any cytotoxicity. Interestingly, ßBA significantly inhibited the phosphorylation of IκB, Btk, and PLCγ2 and the degradation of IκB. Additionally, ßBA strongly inhibited the mRNA and protein expression of c-Fos and NFATc1 induced by RANKL and subsequently attenuated the expression of osteoclast marker genes, such as OC-STAMP, DC-STAMP, ß3-integrin, MMP9, ATP6v0d2, and CtsK. These results suggest that ßBA is a potential therapeutic candidate for the treatment of excessive osteoclast-induced bone diseases such as osteoporosis.


Asunto(s)
Agammaglobulinemia Tirosina Quinasa/metabolismo , Resorción Ósea , Regulación de la Expresión Génica , Osteoclastos/metabolismo , Fosfolipasa C gamma/metabolismo , Ligando RANK , Triterpenos/farmacología , Animales , Boswellia , Diferenciación Celular , Técnicas de Cocultivo , Masculino , Ratones , Ratones Endogámicos ICR , FN-kappa B/metabolismo , Osteoblastos/metabolismo , Osteogénesis/efectos de los fármacos , Osteoporosis/metabolismo , Fosforilación , Transducción de Señal
14.
Biotechnol Bioeng ; 117(9): 2658-2667, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32484909

RESUMEN

The emerging field of regenerative medicine has revealed that the exosome contributes to many aspects of development and disease through intercellular communication between donor and recipient cells. However, the biological functions of exosomes secreted from cells have remained largely unexplored. Here, we report that the human hepatic progenitor cells (CdHs)-derived exosome (EXOhCdHs ) plays a crucial role in maintaining cell viability. The inhibition of exosome secretion treatment with GW4869 results in the acceleration of reactive oxygen species (ROS) production, thereby causing a decrease of cell viability. This event provokes inhibition of caspase dependent cell death signaling, leading to a ROS-dependent cell damage response and thus induces promotion of antioxidant gene expression or repair of cell death of hypoxia-exposed cells. Together, these findings show the effect of exosomes in regeneration of liver cells, and offer valuable new insights into liver regeneration.


Asunto(s)
Antioxidantes , Exosomas , Hepatocitos/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Células Madre/efectos de los fármacos , Antioxidantes/química , Antioxidantes/metabolismo , Antioxidantes/farmacología , Muerte Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Niño , Exosomas/química , Exosomas/metabolismo , Femenino , Hepatocitos/metabolismo , Humanos , Células Madre/metabolismo
15.
J Nat Prod ; 83(4): 1174-1182, 2020 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-32237724

RESUMEN

The increase of bone-resorbing osteoclast activity in bone remodeling is the major characteristic of various bone diseases. Thus, inhibiting osteoclastogenesis and bone-resorbing function may be an effective therapeutic target for bone diseases. Betulinic acid (BA), a natural plant-derived pentacyclic triterpenoid compound, is known to possess numerous pharmacological and biochemical properties including anti-inflammatory, anticancer, and antiadipogenic activity. However, the effect of BA on osteoclast differentiation and function in bone metabolism has not been demonstrated so far. In this study, we investigated whether BA could suppress RANKL-induced osteoclastogenesis and bone resorption. Interestingly, BA significantly suppressed osteoclastogenesis by decreasing the phosphorylation of Akt and IκB, as well as PLCγ2-Ca2+ signaling, in pathways involved in early osteoclastogenesis as well as through the subsequent suppression of c-Fos and NFATc1. The inhibition of these pathways by BA was once more confirmed by retrovirus infection of constitutively active (CA)-Akt and CA-Ikkß retrovirus and measurement of Ca2+ influx. BA also significantly inhibited the expression of osteoclastogenesis-specific marker genes. Moreover, we found that BA administration restored the bone loss induced through acute lipopolysaccharide injection in mice by a micro-CT and histological analysis. Our findings suggest that BA is a potential therapeutic candidate for bone diseases involving osteoclasts.


Asunto(s)
Células de la Médula Ósea/efectos de los fármacos , Resorción Ósea/metabolismo , FN-kappa B/antagonistas & inhibidores , Osteogénesis/efectos de los fármacos , Triterpenos Pentacíclicos/farmacología , Fosfolipasa C gamma/farmacología , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/química , Transducción de Señal/efectos de los fármacos , Animales , Lipopolisacáridos/química , Lipopolisacáridos/farmacología , Ratones , Estructura Molecular , Osteoclastos/efectos de los fármacos , Triterpenos Pentacíclicos/química , Fosfolipasa C gamma/química , Fosfolipasa C gamma/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ligando RANK/química , Ligando RANK/metabolismo , Ácido Betulínico
16.
Nutr J ; 19(1): 116, 2020 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-33066775

RESUMEN

BACKGROUND: Obesity defined solely by the Body Mass Index (BMI) may not reflect the true heterogeneity of the obese population. This study aimed to classify the dietary behaviours of overweight and obese individuals and to explore the relationship between patterns of dietary behaviour and cardiometabolic risk factors. METHODS: A total of 259 patients who visited an outpatient weight management clinic at a tertiary hospital and underwent a dietary behaviour assessment between January 2014 and February 2019 were enrolled in the study. Dietary behaviours were assessed in three domains with nine categories, including choice of food (frequently eating out and consumption of instant/fast/takeaway food), eating behaviour (irregular meals; frequent snacking, including eating at night; emotional eating; and overeating/binge eating), and nutrient intake (high-fat/high-calorie foods, salty food, and poorly balanced diet). Latent class analysis (LCA) was used to classify the subjects according to these categories. Associations between latent class and metabolic syndrome were assessed by logistic regression. RESULTS: The subjects were classified into three LCA-driven classes, including a referent class of healthy but unbalanced eaters (n = 118), a class of emotional eaters (n = 53), and a class of irregular unhealthy eaters (n = 88). Compared with the referent class, emotional eaters had a significantly higher BMI (beta = 3.40, P < 0.001) accompanied by metabolic syndrome (odds ratio 2.88, 95% confidence interval 1.16-7.13). CONCLUSIONS: Our three LCA-driven obesity phenotypes could be useful for assessment and management of obesity and metabolic syndrome. The association between emotional eaters and higher BMI and metabolic syndrome was stronger than that with other eaters. Thus, emotional regulation strategies might have benefit for emotional eater's diet.


Asunto(s)
Síndrome Metabólico , Índice de Masa Corporal , Estudios Transversales , Dieta , Conducta Alimentaria , Humanos , Análisis de Clases Latentes , Síndrome Metabólico/epidemiología , Estudios Retrospectivos
17.
Phytother Res ; 34(11): 3029-3040, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32510717

RESUMEN

Securinine (Sec) is a naturally derived compound separated from the roots of Securinega suffruticosa, which has long been used as a herbal medicine. Sec is widely known as a GABA receptor antagonist, it is also known as an innate immune cell agonist and has been reported to increase macrophage activity and promote monocyte maturation. On the basis of these studies, we investigated the effect of Sec on osteoclast differentiation and bone resorbing function. We have found that Sec inhibits RANKL-induced osteoclast differentiation, fusion, actin ring formation, and bone resorbing function by the inhibition of gene expression associated with each stage. Moreover, Sec significantly suppressed osteoclastogenesis by decreasing the phosphorylation of p38, Akt, JNK, IκB, and PLCγ2, in pathways involved in early osteoclastogenesis as well as through the subsequent suppression of c-Fos and NFATc1. Finally, Sec effectively protected bone loss induced by the excessive inflammatory responses and activity of osteoclasts in vivo by a micro-CT and histological analysis. In conclusion, our findings suggest that Sec may be a promising drug for bone metabolic diseases such as osteoporosis, which is associated with the excessive activity of osteoclasts.


Asunto(s)
Azepinas/uso terapéutico , Enfermedades Óseas Metabólicas/tratamiento farmacológico , Medicina de Hierbas/métodos , Compuestos Heterocíclicos de Anillo en Puente/uso terapéutico , Lactonas/uso terapéutico , Osteogénesis/efectos de los fármacos , Piperidinas/uso terapéutico , Animales , Azepinas/farmacología , Enfermedades Óseas Metabólicas/patología , Diferenciación Celular , Compuestos Heterocíclicos de Anillo en Puente/farmacología , Humanos , Lactonas/farmacología , Ratones , Piperidinas/farmacología
18.
Nano Lett ; 19(6): 3707-3715, 2019 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-31117753

RESUMEN

The mechanical flexibility of perovskite solar cells as well as high power conversion efficiency is attracting increasing attention. In addition to existing empirical approaches, such as cyclic bending tests, in this study we report the tensile properties of the perovskite materials themselves. Measuring the tensile properties of free-standing perovskite materials is critical because (1) tensile properties represent the realistic mechanical properties of the film-type perovskite layer in the solar cells including the effects of various defects, and (2) deformation behavior of the perovskite layer at any deformed state of the solar cells can be analyzed using solid mechanics with the tensile properties as input. Critical bending radius of MAPbI3-based flexible solar cells is found to be between 0.5 and 1.0 mm by the decrease in power conversion efficiency during cyclic bending deformation. This finding agrees well with the critical bending radius of 0.66 mm determined based on the elastic deformation limit of 1.17% for MAPbI3 found by in situ tensile testing. Scanning electron microscopy observations and hole-nanoindentation tests suggest that the formation of coarse cracks in the perovskite layers is the primary cause of the decrease in power conversion efficiency observed in flexible perovskite solar cells.

19.
Nano Lett ; 19(2): 971-976, 2019 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-30608699

RESUMEN

Organic-inorganic hybrid perovskites have been investigated extensively for use in perovskite-based solar cells and light-emitting diodes (LEDs) because of their excellent electrical and optical properties. Although the flexibility of perovskite LEDs has been studied through empirical methods such as cyclic bending tests, the flexibility of the perovskite layer has not been investigated systemically. Here, flexible and semitransparent perovskite LEDs are fabricated: a PEDOT:PSS anode and Ag nanowire cathode allow for flexible and semitransparent devices, while the use of a conjugated polyelectrolyte as an interfacial layer reduces the electron injection barrier between the cathode and the electron transport layer (SPW-111), resulting in enhanced device efficiency. Cyclic bending tests performed on the electrodes and in situ hole-nanoindentation tests performed on the constituent materials suggest that mechanical failure occurs in the perovskite MAPbBr3 layer during cyclic bending, leading to a decrease in the luminance. Tensile properties of the MAPbBr3 layer explain the critical bending radius ( rb) of the perovskite LEDs on the order of 1 mm.

20.
Aesthetic Plast Surg ; 44(5): 1833-1842, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32710202

RESUMEN

PURPOSE: As filler procedures have increased in popularity, serious injection-related complications (e.g., blindness and stroke) have also increased in number. Proper and effective training is important for filler procedure safety; however, limitations exist in traditional training methods (i.e. anatomical illustrations and cadaver studies). We aimed to describe the development process and evaluate the usability of a virtual reality (VR)-based aesthetic filler injection training system. MATERIALS AND METHODS: We developed the virtual reality hardware for the training system and a short guide, with a lecture regarding safe filler injection techniques. One hundred clinicians who attended a conference tested the training system. Participants completed system usability scale (SUS) and satisfaction questionnaires. RESULTS: Nearly half of the participants were aged 35-50 years, and 38% had more than 5 years of aesthetic experience. The mean SUS score was 59.8 (standard deviation, 12.23), with no significant differences among the evaluated subgroups. Approximately 76% of participants provided SUS scores of more than 51, indicating acceptable usability. Participants aged 35-50 years were more likely to rate the system as having poor usability than were those aged < 35 years (odds ratio = 5.20, 95% confidence interval: 1.35-20.08). CONCLUSIONS: This study was the first to develop and explore the usability of a VR-based filler training system. Nearly three-fourths of participants indicated that the training system has an acceptable level of usability. However, assessments in precise target audiences and more detailed usability information are necessary to further refine the training system. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Asunto(s)
Técnicas Cosméticas , Rellenos Dérmicos , Realidad Virtual , Adulto , Ceguera , Estética , Humanos , Persona de Mediana Edad
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