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1.
Small ; : e2402003, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38884191

RESUMEN

Global healthcare based on the Internet of Things system is rapidly transforming to measure precise physiological body parameters without visiting hospitals at remote patients and associated symptoms monitoring. 2D materials and the prevailing mood of current ever-expanding MXene-based sensing devices motivate to introduce first the novel iridium (Ir) precious metal incorporated vanadium (V)-MXene via industrially favored emerging atomic layer deposition (ALD) techniques. The current work contributes a precise control and delicate balance of Ir single atomic forms or clusters on the V-MXene to constitute a unique precious metal-MXene embedded heterostructure (Ir-ALD@V-MXene) in practical real-time sensing healthcare applications to thermography with human-machine interface for the first time. Ir-ALD@V-MXene delivers an ultrahigh durability and sensing performance of 2.4% °C-1 than pristine V-MXene (0.42% °C-1), outperforming several conventionally used MXenes, graphene, underscoring the importance of the Ir-ALD innovative process. Aberration-corrected advanced ultra-high-resolution transmission/scanning transmission electron microscopy confirms the presence of Ir atomic clusters on well-aligned 2D-layered V-MXene structure and their advanced heterostructure formation (Ir-ALD@V-MXene), enhanced sensing mechanism is investigated using density functional theory (DFT) computations. A rational design empowering the Ir-ALD process on least explored V-MXene can potentially unfold further precious metals ALD-process developments for next-generation wearable personal healthcare devices.

2.
J Surg Res ; 295: 231-239, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38041902

RESUMEN

INTRODUCTION: To investigate the significance of perioperative hepatitis B virus (HBV) DNA changes for predicting recurrence in patients with HBV-related hepatocellular carcinoma (HCC) undergoing liver resection (LR). METHODS: From 2013 to 2020, 241 patients with HBV-related HCC who underwent LR in five Hallym university-affiliated hospitals were enrolled. The serum HBV DNA level, together with other clinicopathological variables, was analyzed for association with HCC recurrence. RESULTS: Preoperatively, 99 patients had undetectable HBV DNA and 142 had detectable viral levels. Of those with detectable viral levels, 72 rapidly progressed to undetectable levels within 3 mo after LR (Rapid group), and 70 showed persistently detectable levels (Nonrapid group). The Rapid group had a better recurrence-free survival (RFS) rate than the Nonrapid group (1-y, 3-y RFS = 75.4%, 57.3%, versus 54.7%, 39.9%, respectively, P = 0.012). In the subgroup analysis, the Rapid group had a better RFS rate in early stages (1-y, 3-y RFS = 82.6%, 68.5%, versus 62.8%, 45.8%, respectively, P = 0.005); however, the RFS rates between the two groups were comparable in the advanced stage (1-y, 3-y RFS = 61.1%, 16.7% versus 45.5%, 22.7%, respectively, P = 0.994). Among the 142 patients with preoperatively detectable HBV DNA, persistently detectable HBV DNA within 3 mo postoperatively (hazard ratio [HR] = 1.7, P = 0.022), large tumor size (HR = 2.7, P < 0.001), multiple tumors (HR = 3.2, P < 0.001), and microvascular invasion (HR = 1.7, P = 0.028) were independent risk factors for RFS in multivariate analysis. CONCLUSIONS: Rapidly undetectable HBV DNA after LR is associated with a better prognosis for recurrence in patients with HCC. Therefore, appropriate treatment and/or screening may be necessary for patients who do not return to undetectable HBV DNA after LR.


Asunto(s)
Carcinoma Hepatocelular , Hepatitis B Crónica , Hepatitis B , Neoplasias Hepáticas , Humanos , Virus de la Hepatitis B/genética , Recurrencia Local de Neoplasia/patología , ADN Viral/genética , Estadificación de Neoplasias , Hepatectomía/efectos adversos , Estudios Retrospectivos , Hepatitis B/complicaciones , Hepatitis B/patología , Hepatitis B/cirugía , Hepatitis B Crónica/complicaciones , Hepatitis B Crónica/patología , Hepatitis B Crónica/cirugía
3.
Nano Lett ; 23(11): 5391-5398, 2023 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-36971404

RESUMEN

Since thermometry of human skin is critical information that provides important aspects of human health and physiology, accurate and continuous temperature measurement is required for the observation of physical abnormalities. However, conventional thermometers are uncomfortable because of their bulky and heavy features. In this work, we fabricated a thin, stretchable array-type temperature sensor using graphene-based materials. Furthermore, we controlled the degree of graphene oxide reduction and enhanced the temperature sensitivity. The sensor exhibited an excellent sensitivity of 2.085% °C-1. The overall device was designed in a wavy meander shape to provide stretchability for the device so that precise detection of skin temperature could be performed. Furthermore, polyimide film was coated to secure the chemical and mechanical stabilities of the device. The array-type sensor enabled spatial heat mapping with high resolution. Finally, we introduced some practical applications of skin temperature sensing, suggesting the possibility of skin thermography and healthcare monitoring.


Asunto(s)
Grafito , Temperatura Cutánea , Humanos , Temperatura , Termografía
4.
J Neurooncol ; 165(1): 113-126, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37864645

RESUMEN

BACKGROUND: The immortality of cancer cells relies on maintaining the length of telomeres, which prevents cellular senescence and enables unlimited replication. However, little is currently known about telomerase activity and the alternative lengthening of telomeres (ALT) in vestibular schwannomas. In this study we aimed to elucidate the role that telomerase and ALTs play in vestibular schwannomas. METHODS: To address this gap, we conducted a study where we used the gene set variation analysis algorithm with bulk RNA-seq and single-cell RNA-seq to identify the characteristics of each group of patients with vestibular schwannomas, based on their telomere maintenance mechanism subtype. RESULTS: Our findings suggest that patients with relatively high ALT-like groups have a better prognosis than those with relatively high telomerase groups. Specifically, we found that the high telomerase group had relatively higher antigen-presenting cell (APC) activity than the high ALT like group. At the single-cell level, microglia, neutrophils, and fibroblasts showed high telomerase activity and relatively high APC activity compared to other cell types. In addition, Schwann cells in the group with low ALT levels exhibited elevated immune activity at the single-cell level. CONCLUSION: These results suggest that personalized drug therapy could be developed from the perspective of precision medicine for patients with relatively high telomerase activity and a high ALT-like group.


Asunto(s)
Neuroma Acústico , Telomerasa , Humanos , Telomerasa/genética , Telomerasa/metabolismo , Telómero , Homeostasis del Telómero
5.
Eur Radiol ; 33(9): 5965-5975, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36988715

RESUMEN

OBJECTIVE: This prospective multicenter study aimed to evaluate the diagnostic performance of 80-kVp thin-section pancreatic CT in determining pancreatic ductal adenocarcinoma (PDAC) resectability according to the recent National Comprehensive Cancer Network (NCCN) guidelines. METHODS: We prospectively enrolled surgical resection candidates for PDAC from six tertiary referral hospitals (study identifier: NCT03895177). All participants underwent pancreatic CT using 80 kVp tube voltage with 1-mm reconstruction interval. The local resectability was prospectively evaluated using NCCN guidelines at each center and classified into three categories: resectable, borderline resectable, and unresectable. RESULTS: A total of 138 patients were enrolled; among them, 60 patients underwent neoadjuvant therapy. R0 resection was achieved in 103 patients (74.6%). The R0 resection rates were 88.7% (47/53), 52.4% (11/21), and 0.0% (0/4) for resectable, borderline resectable, and unresectable disease, respectively, in 78 patients who underwent upfront surgery. Meanwhile, the rates were 90.9% (20/22), 76.7% (23/30), and 25.0% (2/8) for resectable, borderline resectable, and unresectable PDAC, respectively, in patients who received neoadjuvant therapy. The area under curve of high-resolution CT in predicting R0 resection was 0.784, with sensitivity, specificity, and accuracy of 87.4% (90/103), 48.6% (17/35), and 77.5% (107/138), respectively. Tumor response was significantly associated with the R0 resection after neoadjuvant therapy (odds ratio [OR] = 38.99, p = 0.016). CONCLUSION: An 80-kVp thin-section pancreatic CT has excellent diagnostic performance in assessing PDAC resectability, enabling R0 resection rates of 88.7% and 90.9% for patients with resectable PDAC who underwent upfront surgery and patients with resectable PDAC after neoadjuvant therapy, respectively. KEY POINTS: • The margin-negative (R0) resection rates were 88.7% (47/53), 52.4% (11/21), and 0.0% (0/4) for resectable, borderline resectable, and unresectable pancreatic ductal adenocarcinoma (PDAC), respectively, on 80-kVp thin-section pancreatic CT in the 78 patients who underwent upfront surgery. • Among the 60 patients who underwent neoadjuvant therapy, the R0 rates were 90.9% (20/22), 76.7% (23/30), and 25.0% (2/8) for resectable, borderline resectable, and unresectable PDAC, respectively. • Tumor response, along with the resectability status on pancreatic CT, was significantly associated with the R0 resection rate after neoadjuvant therapy.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Estudios Prospectivos , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/cirugía , Neoplasias Pancreáticas/patología , Carcinoma Ductal Pancreático/diagnóstico por imagen , Carcinoma Ductal Pancreático/cirugía , Carcinoma Ductal Pancreático/patología , Tomografía Computarizada por Rayos X/métodos , Terapia Neoadyuvante , Neoplasias Pancreáticas
6.
BMC Musculoskelet Disord ; 24(1): 540, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37393227

RESUMEN

BACKGROUND: During the coronavirus disease (COVID-19) pandemic, the amount of moderate- to high-intensity physical activity significantly decreased. Therefore, the epidemiology of musculoskeletal diseases could possibly have changed. We assessed changes in the incidence of and variance in non-traumatic orthopedic diseases before and after the COVID-19 pandemic in Korea. METHODS: This study included data from the Korea National Health Insurance Service, which covers the entire Korean population (approximately 50 million), from January 2018 to June 2021. Using International Classification of Diseases, Tenth Revision codes, 12 common orthopedic diseases were evaluated, including cervical disc disorders, lumbar disc disorders, forward head posture, myofascial pain syndrome, carpal tunnel syndrome, tennis elbow, frozen shoulder, rheumatoid arthritis, gout, hip fracture, distal radius fracture, and spine fracture diseases. "Pre-COVID-19" was the period until February 2020, and "COVID-19 pandemic period" was the period starting March 2020. Differences in the mean incidence and variance of diseases before and during the COVID-19 pandemic were compared. RESULTS: In most cases, the incidence of orthopedic diseases decreased at the beginning of the pandemic and then increased thereafter. Among the 12 diseases, the incidence of three diseases showed a statistically significant change. The incidence of myofascial pain syndrome (P < 0.001) was lower during the COVID-19 pandemic than during the pre-COVID-19 period. The incidences of frozen shoulder (P < 0.001) and gout (P = 0.043) were higher during the COVID-19 pandemic than during the pre-COVID-19 period. However, no statistical difference in disease variations was observed between the two periods. CONCLUSIONS: The incidence of orthopedic diseases varied during the COVID-19 pandemic among the Korean population. Although the incidence of myofascial pain syndrome was lower, that of frozen shoulder and gout was higher during the COVID-19 pandemic than during the pre-COVID-19 period. No disease variations during the COVID-19 pandemic were found.


Asunto(s)
Bursitis , COVID-19 , Fibromialgia , Fracturas Óseas , Gota , Degeneración del Disco Intervertebral , Enfermedades Musculoesqueléticas , Humanos , Estudios Retrospectivos , Incidencia , Pandemias , COVID-19/epidemiología , República de Corea/epidemiología
7.
BMC Cancer ; 22(1): 1077, 2022 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-36261806

RESUMEN

BACKGROUND: Various cancer stem cell (CSC) biomarkers and the genes encoding them in head and neck squamous cell carcinoma (HNSCC) have been identified and evaluated. However, the validity of these factors in the prognosis of HNSCC has been questioned and remains unclear. In this study, we examined the clinical significance of CSC biomarker genes in HNSCC, using five publicly available HNSCC cohorts. METHODS: To predict the prognosis of patients with HNSCC, we developed and validated the expression signatures of CSC biomarker genes whose mRNA expression levels correlated with at least one of the four CSC genes (CD44, MET, ALDH1A1, and BMI1). RESULTS: Patients in The Cancer Genome Atlas (TCGA) HNSCC cohort were classified into CSC gene expression-associated high-risk (CSC-HR; n = 285) and CSC gene expression-associated low-risk (CSC-LR; n = 281) subgroups. The 5-year overall survival and recurrence-free survival rates were significantly lower in the CSC-HR subgroup than in the CSC-LR subgroup (p = 0.04 and 0.02, respectively). The clinical significance of the CSC gene expression signature was validated using four independent cohorts. Analysis using Cox proportional hazards models showed that the CSC gene expression signature was an independent prognostic factor of non-oropharyngeal HNSCC which mostly indicates HPV (-) status. Furthermore, the CSC gene expression signature was associated with the prognosis of HNSCC patients who received radiotherapy. CONCLUSION: The CSC gene expression signature is associated with the prognosis of HNSCC and may help in personalized treatments for patients with HNSCC, especially in cases with HPV (-) status who were classified in more detail.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Infecciones por Papillomavirus , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Transcriptoma , Neoplasias de Cabeza y Cuello/patología , Infecciones por Papillomavirus/patología , Carcinoma de Células Escamosas/patología , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Pronóstico , Células Madre Neoplásicas/metabolismo , ARN Mensajero/metabolismo
8.
Doc Ophthalmol ; 144(2): 153-162, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34997406

RESUMEN

PURPOSE: To report a case of Vogt-Koyanagi-Harada (VKH) syndrome-like posterior uveitis after nivolumab administration to treat an ovarian cancer with an electrophysiological finding. A 61-year-old woman with ovarian cancer (stage 3A) and salpingo-oophorectomy surgery history visited the clinic complaining of blurred vision in both eyes. She had been enrolled a clinical trial using nivolumab in patients with ovarian cancer. She received four cycles of nivolumab administration and experienced blurred vision one week before the initial visit. There was no remarkable finding in the anterior segment and the vitreous body. Multiple subretinal fluid accumulations and serous retinal detachment were identified on the posterior pole. Subretinal fluid with choroidal folding was noted in optical coherence tomography, and multiple leakage points were also observed in wide-field fundus fluorescein angiography. Therefore, intravenous high-dose steroid pulse therapy was applied under the diagnosis of VKH syndrome-like posterior uveitis induced by an immunotherapy agent. After steroid therapy, the subretinal fluid was absorbed completely, and the patient's visual acuity was recovered to the normal range. The amplitudes in the multifocal electroretinogram were also restored after the treatment. CONCLUSION: Nivolumab is a human IgG4 monoclonal antibody and an immune checkpoint inhibitor. It is associated with the upregulation of T-cell activity by interfering with the interaction between the programmed death-1 (PD-1) receptor and the PD-ligand. Targeted therapy using immunotherapy agents has been widely used for malignant melanoma, lung cancer, renal cell carcinoma, and other cancers. However, immunotherapy agents such as nivolumab can induce autoimmune-related adverse events including uveitis. This report suggests that VKH syndrome-like posterior uveitis could be induced by nivolumab administration for an ovarian cancer treatment, which was resolved by steroid pulse therapy.


Asunto(s)
Neoplasias Ováricas , Uveítis Posterior , Uveítis , Síndrome Uveomeningoencefálico , Electrorretinografía , Femenino , Angiografía con Fluoresceína , Humanos , Persona de Mediana Edad , Nivolumab/efectos adversos , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/tratamiento farmacológico , Tomografía de Coherencia Óptica , Síndrome Uveomeningoencefálico/inducido químicamente , Síndrome Uveomeningoencefálico/diagnóstico , Síndrome Uveomeningoencefálico/tratamiento farmacológico
9.
Gerontology ; 68(5): 518-528, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35580570

RESUMEN

BACKGROUND: Identifying the risk factors for falls among the elderly population is arguably one of the most imperative public health issues in the current aging society. OBJECTIVES: This study aimed to determine the associations between depressive symptoms, subjective cognitive decline (SCD), and poor subjective sleep quality and the risk of slips/falls in a Korean older population. METHODS: This cross-sectional study involved 228,340 elderly individuals living in Korea. Measurements included self-reported depressive symptoms, SCD, and self-reported sleep quality. The risk of slips/falls was dichotomized depending on whether slips/falls had occurred during the past year, and the associations between different risk factors and slips/falls were explored. Multiple logistic regression was used to obtain the odds ratios (ORs) and 95% confidence intervals (CIs). Complex sampling methods were used to estimate the weighted value of each participant. RESULTS: The risk of slips/falls was significantly associated with high levels of depressive symptoms (adjusted OR 1.06, 95% CI: 1.05-1.07) and SCD (adjusted OR 1.33, 95% CI: 1.19-1.50). Regarding each sleep quality component, the adjusted ORs for slips/falls were 1.85 for very poor sleep quality, 1.49 for long sleep latency, 1.04 for <5 h of sleep duration, 1.32 for low sleep efficiency, 2.78 for high sleep disturbance, 1.52 for the use of sleep medication ≥3 times a week, and 1.82 for high daytime dysfunction due to sleep problems compared to the respective good sleep conditions. CONCLUSIONS: Our results demonstrated that depressive symptoms, SCD, and poor subjective sleep quality are independent factors affecting the occurrence of slips/falls. Thus, efforts to manage depressive symptoms and cognitive decline early and to improve sleep quality can be an alternative strategy to decrease the likelihood of falls.


Asunto(s)
Disfunción Cognitiva , Trastornos del Inicio y del Mantenimiento del Sueño , Trastornos del Sueño-Vigilia , Accidentes por Caídas , Anciano , Disfunción Cognitiva/epidemiología , Estudios Transversales , Depresión/epidemiología , Humanos , República de Corea/epidemiología , Autoinforme , Sueño , Calidad del Sueño , Trastornos del Sueño-Vigilia/complicaciones , Trastornos del Sueño-Vigilia/epidemiología
10.
BMC Public Health ; 22(1): 476, 2022 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-35272663

RESUMEN

BACKGROUND: Participation in exercise, and dietary and nutritional intakes have an impact on the risk and prevalence of metabolic syndrome (MetS), but these effects may differ according to whether a person lives alone or in a multi-person household. We analyzed differences in physical activity (PA) levels and energy intake according to household-type and MetS presence among young adults, to investigate the relationships among these factors. METHODS: Data of 3974 young adults (aged > 19 years and < 40 years) were obtained from the Korean National Health and Nutrition Examination Survey (2016-2018). We analyzed PA levels (occupational and recreational PA, and transport) and energy intake (total, carbohydrate, protein, and fat). RESULTS: Logistic regression data showed that low PA levels and higher energy intake were associated with MetS incidence and its components in young adults, after adjusting for body mass index, smoking, household-type, and sex. Overall, there was no significant difference in PA level between the MetS and non-MetS group. The total energy intake was higher in the MetS than in the non-MetS group (p <  0.05). These results were similar to those found in multi-person households. In single-person households, the MetS group had significantly lower PA levels (p <  0.01) and total energy intake (p <  0.05) than the non-MetS group. CONCLUSIONS: We found significant association among low PA levels, high energy intake, and MetS components in young Korean adults, but with patterns differing according to household type. Energy intake was higher in young adults with than those without MetS, who lived in multi-person households, while young adults with MetS who lived alone had lower PA levels and lower energy intake than those without MetS. These findings highlight the need for different approaches of implementing PA and nutrition strategies according to the type of household in order to prevent MetS.


Asunto(s)
Síndrome Metabólico , Estudios Transversales , Ingestión de Energía , Ejercicio Físico , Humanos , Síndrome Metabólico/etiología , Encuestas Nutricionales , Prevalencia , República de Corea/epidemiología , Factores de Riesgo , Adulto Joven
11.
J Korean Med Sci ; 37(38): e288, 2022 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-36193640

RESUMEN

BACKGROUND: Although ankle fractures are among the most common fractures, nationwide population-based data on the epidemiology of patients with ankle fractures are scarce. This study aimed to perform an epidemiological analysis of all ankle fractures in Korea from 2010 through 2018. METHODS: We used national registries from the Korean Health Insurance Review and Assessment Service from 2009 to 2018. The annual incidence of the ankle fracture was calculated. The incidence was also calculated according to gender and age. Trends of fracture subtypes were also analyzed. Then, the incidence of ankle fractures by seasonal variation was investigated. RESULTS: A total of 735,073 ankle fractures were identified in 461,497,758 people for 10 years. The annual incidence of ankle fracture was 171.37/100,000 persons in 2018, with a male to female ratio of 0.78. Interesting differences in the ankle fracture trends were observed between gender. Male shows the highest incidence in adolescence, and the even distribution has lasted for the rest of their lives. In females, the incidence of ankle fracture showed an increasing tendency as their age increased. There was a clear difference in the incidence rate of each season according to age. Ankle fractures occurred more in spring and autumn in children and adolescents and most in winter in the elderly. CONCLUSION: Ankle fracture risk was different between sex and exhibited seasonal variations. Our findings can be used for epidemiological awareness and prevention campaigns for ankle fractures.


Asunto(s)
Fracturas de Tobillo , Adolescente , Anciano , Fracturas de Tobillo/epidemiología , Fracturas de Tobillo/etiología , Niño , Femenino , Humanos , Incidencia , Masculino , Sistema de Registros , República de Corea/epidemiología , Estaciones del Año
12.
Am J Otolaryngol ; 43(1): 103222, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34536916

RESUMEN

BACKGROUND: Vibrant SoundBridge® (VSB), a semi-implantable middle ear device, is one of the treatment options for patients with mild-to-severe sensorineural hearing loss or mixed hearing loss. Herein, we report delayed device failure after VSB surgery in two patients. CASE PRESENTATION: In both cases, a revision surgery was performed for the removal of the device; dissociation of the floating mass transducer (FMT) and coupler was noticed in one patient, and dissociation of the FMT-coupler complex from the short process of the incus in the other. In Case 1, the vibration-like sounds disappeared after the surgery. In Case 2, wearing bilateral hearing aids improved hearing after removal surgery, but complaints regarding speech discrimination persisted. Both cases show the importance of not loosening the connectivity between the FMT, coupler, and short process of the incus during VSB surgery. CONCLUSIONS: To our knowledge, there has been no report of dissociation from the short process of the incus or the dissociation between an FMT and the coupler.


Asunto(s)
Perdida Auditiva Conductiva-Sensorineural Mixta/cirugía , Pérdida Auditiva Sensorineural/cirugía , Prótesis Osicular/efectos adversos , Falla de Prótesis , Transductores/efectos adversos , Anciano , Remoción de Dispositivos , Femenino , Humanos , Yunque/cirugía , Masculino , Ilustración Médica , Persona de Mediana Edad , Diseño de Prótesis
13.
Int J Mol Sci ; 23(21)2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36362098

RESUMEN

We demonstrated highly active and durable hybrid catalysts (HCs) composed of small reduced graphene oxide (srGO) and carbon nanotubes (CNTs) for use as oxygen reduction reaction (ORR) catalysts in proton exchange membrane fuel cells. Pt/srGO and Pt/CNTs were prepared by loading Pt nanoparticles onto srGO and CNTs using a polyol process, and HCs with different Pt/CNT and Pt/srGO ratios were prepared by mechanically mixing the two components. The prepared HCs consisted of Pt/CNTs well dispersed on Pt/srGO, with catalyst HC55, which was prepared using Pt/srGO and Pt/CNTs in a 5:5 ratio, exhibiting excellent oxygen reduction performance and high stability over 1000 cycles of the accelerated durability test (ADT). In particular, after 1000 cycles of the ADT, the normalized electrochemically active surface area of Pt/HC55 decreased by 11.9%, while those of Pt/srGO and Pt/C decreased by 21.2% and 57.6%, respectively. CNTs have strong corrosion resistance because there are fewer defect sites on the surface, and the addition of CNTs in rGO further improved the durability and the electrical conductivity of the catalyst. A detailed analysis of the structural and electrochemical properties of the synthesized catalysts suggested that the synergetic effects of the high specific surface area of srGO and the excellent electrical conductivity of CNTs were responsible for the enhanced efficiency and durability of the catalysts.


Asunto(s)
Nanotubos de Carbono , Nanotubos de Carbono/química , Protones , Platino (Metal)/química , Oxígeno/química
14.
Doc Ophthalmol ; 142(3): 293-304, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33389330

RESUMEN

PURPOSE: To quantify metamorphopsia with a novel objective method in patients with epiretinal membrane (ERM) and to compare the relationships among metamorphopsia scores, spectral-domain optical coherence tomography (OCT) findings, and multifocal electroretinogram (mfERG) results. METHODS: This study included 52 eyes of 52 patients with idiopathic ERM who underwent comprehensive ophthalmologic examinations, including measurement of best-corrected visual acuity (BCVA), OCT, and mfERG. The degree of metamorphopsia was quantified using MonPack One® (Metrovision, Perenchies, France). On the topographic map of the early treatment diabetic retinopathy (ETDRS) grid, retinal thickness in the central, superior, inferior, nasal, and temporal subfields were measured, and metamorphopsia scores for each corresponding subfield were also obtained. The amplitudes and implicit times of mERG were elicited from each subfield. Then, the correlations among metamorphopsia scores, OCT findings, and mfERG responses were analyzed. RESULTS: The mean age of the patients was 65.3 ± 18.5 y, and the average metamorphopsia score of the individual subfields was 2.03 ± 1.18. Initial BCVA was 0.50 ± 0.12 logMAR, but there was no significant correlation between metamorphopsia scores and BCVA. The metamorphopsia scores from the central subfields showed significant correlations with central retinal thickness (CRT) (p = 0.001). The mean metamorphopsia scores in the central subfield showed a significant relationship with the mean N1 and P1 amplitudes (p = 0.001, p = 0.048, respectively), while no relationship was observed between metamorphopsia scores and mfERG amplitudes in other subfields. CONCLUSIONS: The degree of metamorphopsia in patients with ERM could be objectively quantified in each subfield using a novel metamorphopsia test. The metamorphopsia scores were significantly correlated with retinal thickness, especially at the central subfields, and the scores in the central subfields were significantly correlated with the N1 and P1 amplitudes of mfERG. Thus, the metamorphopsia test can be a useful method to evaluate metamorphopsia symptoms for patients with ERM.


Asunto(s)
Membrana Epirretinal , Tomografía de Coherencia Óptica , Electrorretinografía , Membrana Epirretinal/diagnóstico por imagen , Humanos , Trastornos de la Visión/diagnóstico , Agudeza Visual
15.
Int J Clin Oncol ; 26(9): 1752-1758, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34091796

RESUMEN

BACKGROUND: This study aimed to evaluate the association between cervical cancer and the occurrence of osteoporosis and osteoporotic fracture using data from the Korean Genome and Epidemiology Study (KoGES). METHODS: In this national cohort study using KoGES health examination (HEXA) data, we extracted data for patients with cervical cancer (n = 493) and control participants (n = 77,571); we then analyzed the occurrence of osteoporosis and osteoporotic fracture at baseline from 2004 to 2013 and during follow-up from 2012 to 2016. A logistic regression model was used to analyze the odds ratios (ORs) and the 95% confidence intervals (CIs). RESULTS: The ORs (95% CIs) for osteoporosis and osteoporotic fracture were 1.49 (95% CI 1.15-1.92, p = 0.03) and 1.06 (95% CI 0.82-1.38, p = 0.634), respectively, in the cervical cancer group. The ORs (95% CIs) for osteoporosis were 2.12 (95% CI 1.14-3.95, p = 0.018) in the ≤ 51-year-old group and 1.43 (95% CI 1.08-1.89, p = 0.011) in the ≥ 52-year-old group of cervical cancer patients. CONCLUSION: We concluded that Korean women with cervical cancer had a higher risk of osteoporosis than healthy women, but the same finding was not observed for osteoporotic fracture.

16.
Am J Otolaryngol ; 42(6): 103079, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34020179

RESUMEN

OBJECTIVES: Nasal obstruction is common in patients with obstructive sleep apnea (OSA). Nonetheless, the effectiveness of isolated nasal surgery in treatment of OSA remains controversial. This study is to evaluate the subjective and objective outcome after isolated nasal surgery in patients with OSA and to determine the associated factors related to the success rate of isolated nasal surgery. METHODS: The study population consisted of 35 patients with nasal obstruction who had been diagnosed with OSA and were undergoing septoplasty and inferior turbinate reduction to correct nasal pathologies. Preoperative drug-induced sleep endoscopy was performed to evaluate the obstruction site. Patients were assessed before and after nasal surgery using subjective outcomes measures, including the Visual Analog Scale and Epworth Sleepiness Scale, as well as by overnight polysomnography. RESULTS: All patients experienced improved nasal breathing postoperatively. At 6 months postoperatively, patients exhibited significant symptomatic improvement in snoring, sleep apnea, morning headache, tiredness, and daytime sleepiness. Postoperative polysomnography revealed significant improvement in the apnea-hypopnea index, respiratory disturbance index, and percentage of time with oxygen saturation < 90%. Although the overall success rate of nasal surgery alone was 14.3%, the criteria for success were met in 50% of patients with allergic rhinitis. Furthermore, the success rate was significantly higher in patients with moderate to severe nasal obstruction than in patients with mild nasal obstruction. CONCLUSION: Among patients with OSA, those with allergic rhinitis and severe nasal obstruction are likely to have a better surgical outcome following isolated nasal surgery.


Asunto(s)
Rinitis Alérgica , Apnea Obstructiva del Sueño/cirugía , Adolescente , Adulto , Anciano , Niño , Endoscopía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tabique Nasal/cirugía , Nariz/fisiopatología , Gravedad del Paciente , Polisomnografía , Estudios Prospectivos , Respiración , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/fisiopatología , Resultado del Tratamiento , Cornetes Nasales/cirugía , Adulto Joven
17.
Sensors (Basel) ; 21(3)2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33498589

RESUMEN

Near-field communication (NFC) is a low-power wireless communication technology used in contemporary daily life. This technology contributes not only to user identification and payment methods, but also to various biomedical fields such as healthcare and disease monitoring. This paper focuses on biomedical applications among the diverse applications of NFC. It addresses the benefits of combining traditional and new sensors (temperature, pressure, electrophysiology, blood flow, sweat, etc.) with NFC technology. Specifically, this report describes how NFC technology, which is simply applied in everyday life, can be combined with sensors to present vision and opportunities to modern people.


Asunto(s)
Comunicación , Tecnología Inalámbrica , Humanos , Sudor
18.
Nano Lett ; 20(10): 6966-6973, 2020 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-32870015

RESUMEN

We explore the ultrafast optical response of graphene subjected to intense (∼106 V/cm) local (∼10 nm) electric fields. Nanoscale gating of graphene is achieved using a voltage-biased, SrTiO3-based conductive nanowire junction "written" directly under the graphene and isolated from it by an insulating ultrathin (<2 nm) LaAlO3 barrier. Upon illumination with ultrafast visible-to-near-infrared (VIS-NIR) light pulses, the local field from the nanojunction creates a strong gate-tunable second-order nonlinearity in the graphene and produces a substantial difference-frequency (DFG) and sum-frequency generation (SFG) response detected by the nanojunction. Spectrally sharp, gate-tunable extinction features (>99.9%) are observed in the VIS-NIR and SFG spectral ranges, in parameter regimes that are positively correlated with the enhanced nonlinear response. The observed graphene-light interaction and nonlinear response are of fundamental interest and open the way for future exploitation in graphene-based optical devices such as phase shifters, modulators, and nanoscale THz sources.

19.
Clin Otolaryngol ; 46(5): 998-1004, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33754477

RESUMEN

OBJECTIVES: Sialocele and salivary fistula are not serious but troublesome complications after parotidectomy. Various modalities have been introduced to prevent postoperative saliva-related complications. However, clinical trials assessing the prophylactic use of botulinum toxin (BTX) for parotidectomy have not been conducted yet. Herein, we report a pilot study investigating the safety and efficacy of intraoperative BTX (iBTX) injection in partial superficial parotidectomy (PSP). PARTICIPANTS: Patients with benign parotid tumour were prospectively recruited for this clinical trial from 2017 to 2019. The study participants underwent PSP with iBTX injection. We retrospectively reviewed the clinical information of all the consecutive patients who underwent PSP without iBTX from 2013 to 2019. These patients were divided into two groups: the iBTX group (n = 36) and the control group (n = 54). RESULTS: Permanent facial palsy was not observed in either group. Two patients (3.7%) had transient marginal palsy in the control group but none had it in the iBTX group. The incidence of sialocele was significantly lower in the iBTX group than in the control group (2.8% vs. 20.4%, P < .05). Although the incidence of salivary fistula was lower in the iBTX group than in the control group (0% vs. 7.4%), no significant difference was determined between the two groups (P = .147). Total drainage volume was significantly lower in the iBTX group than in the control group (55.0 mL vs. 116.6 mL, P < .001). CONCLUSIONS: iBTX injection may be safe and effective in reducing sialocele and postoperative drainage in PSP. It might be a useful option to prevent saliva-related complications after PSP.


Asunto(s)
Toxinas Botulínicas Tipo A/administración & dosificación , Fármacos Neuromusculares/administración & dosificación , Neoplasias de la Parótida/cirugía , Complicaciones Posoperatorias/prevención & control , Adulto , Anciano , Toxinas Botulínicas Tipo A/efectos adversos , Femenino , Humanos , Cuidados Intraoperatorios , Masculino , Persona de Mediana Edad , Fármacos Neuromusculares/efectos adversos , Neoplasias de la Parótida/patología , Proyectos Piloto , Estudios Prospectivos
20.
Inorg Chem ; 59(5): 3042-3052, 2020 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-31995361

RESUMEN

As one of the perovskite families, potassium sodium niobates (K1-xNax)NbO3 (KNN) have been gaining tremendous attention due to their various functional properties which can be largely determined by their crystallographic phase and composition. However, a selective evolution of different phases for KNN with controlled composition can be difficult to achieve, especially in solution chemical synthesis because of its strong tendency to stabilize into orthorhombic phase at conventional synthetic temperature. We herein developed a facile solution approach to control the phase and composition of dopant-free KNN particles selectively through the modification of reaction parameters. A conventional hydrothermal synthesis method yielded orthorhombic KNN particles, while the monoclinic phase, which has never been observed in a bulk counterpart, was kinetically generated by the compositional modification of an intermediate phase under a high-intensity ultrasound irradiation. Cubic KNN particles were stabilized when ethylene glycol was used as a co-solvent together with deionized water through bonding between ethylene glycol molecules and the surface of the KNN. Composite-structured piezoelectric harvesters were fabricated using each phase of KNN particles and the ß-phase poly(vinylidene fluoride-co-trifluoroethylene) polymer. Maximum output power was found for the harvester containing orthorhombic KNN particles. This facile synthetic methodology could pave a new pathway for fabricating numerous phase-controlled materials.

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