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1.
Biomacromolecules ; 20(2): 1109-1117, 2019 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-30605610

RESUMEN

Cancer cells have a large amount of ROS (reactive oxygen species) because of disturbed ROS homeostasis. Cancer cells therefore undertake redox adaptation to drive proliferation in tumor environments and even survive during anticancer treatment by upregulating endogenous antioxidants. As one of antioxidant defense systems, heme oxygenase-1 (HO-1) acts as an essential role in tumor development by offering antioxidant bilirubin to protect cancer cells under stress conditions. It can be therefore reasoned that the combination of ROS generation and HO-1 inhibition would exert synergistic anticancer effects through the amplification of oxidative stress and provide a new opportunity for targeted anticancer therapy. To establish targeted anticancer therapy based on amplified oxidative stress, we developed molecularly engineered polymer, termed CZP, which incorporates ROS generating CA (cinnamaldehyde) and HO-1 inhibiting ZnPP (zinc protoporphyrin) in its backbone and could form stable micelles in aqueous solutions. CZP micelles not only elevated oxidative stress but also suppressed the expression of antioxidant HO-1, leading to apoptotic cell death. CZP micelles could also significantly suppress the tumor growth without body weight loss, tumor recurrence, and noticeable toxicity in organs. This study demonstrates that a combination of ROS generation and HO-1inhibition synergistically magnifies oxidative stress to kill cancer cells and oxidative stress amplifying CZP micelles may provide a promising strategy in anticancer treatment.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Hemo-Oxigenasa 1/antagonistas & inhibidores , Estrés Oxidativo/efectos de los fármacos , Polímeros/química , Especies Reactivas de Oxígeno/metabolismo , Células A549 , Animales , Antioxidantes/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Sistemas de Liberación de Medicamentos/métodos , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Micelas , Oxidación-Reducción/efectos de los fármacos , Protoporfirinas/metabolismo
2.
Pediatr Radiol ; 48(4): 594-601, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29450597

RESUMEN

BACKGROUND: The 320-row multidetector computed tomography (CT) scanner has multiple scan modes, including volumetric modes. OBJECTIVE: To compare the image quality and radiation dose of 320-row CT in three acquisition modes - helical, one-shot volume, and wide-volume scan - at pediatric brain imaging. MATERIALS AND METHODS: Fifty-seven children underwent unenhanced brain CT using one of three scan modes (helical scan, n=21; one-shot volume scan, n=17; wide-volume scan, n=19). For qualitative analysis, two reviewers evaluated overall image quality and image noise using a 5-point grading system. For quantitative analysis, signal-to-noise ratio, image noise and posterior fossa artifact index were calculated. To measure the radiation dose, adjusted CT dose index per unit volume (CTDIadj) and dose length product (DLP) were compared. RESULTS: Qualitatively, the wide-volume scan showed significantly less image noise than the helical scan (P=0.009), and less streak artifact than the one-shot volume scan (P=0.001). The helical mode showed significantly lower signal-to-noise ratio, with a higher image noise level compared with the one-shot volume and wide-volume modes (all P<0.05). The CTDIadj and DLP were significantly lower in the one-shot volume and wide-volume modes compared with those in the helical scan mode (all P<0.05). CONCLUSION: For pediatric unenhanced brain CT, both the wide-volume and one-shot volume scans reduced radiation dose compared to the helical scan mode, while the wide-volume scan mode showed fewer streak artifacts in the skull vertex and posterior fossa than the one-shot volume scan.


Asunto(s)
Encefalopatías/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adolescente , Artefactos , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Tomografía Computarizada Multidetector , Dosis de Radiación , Relación Señal-Ruido , Tomografía Computarizada Espiral
3.
J Korean Acad Nurs ; 54(2): 178-192, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38863187

RESUMEN

PURPOSE: This study aimed to examine the predictive factors of COVID-19 vaccination behavior by evaluating the moderating effect of perceived behavioral control on the theory of planned behavior. METHODS: Data were collected from August 6 to August 31, 2022 from 235 college students (aged 20~29 years) across 12 universities using a structured web-based survey. Statistical analyses were conducted using the SPSS and AMOS software. RESULTS: Attitudes toward COVID-19 vaccination, subjective norms, and intention to be vaccinated significantly influenced COVID-19 vaccination behavior. Attitudes and subjective norms indirectly affected COVID-19 vaccination behavior through intention to vaccinate, whereas intention to vaccinate had a direct effect. The moderating effect of perceived behavioral control on the relationship between subjective norms and intention to vaccinate was significant. CONCLUSION: Interventions that foster a positive attitude toward COVID-19 vaccination and bolster subjective norms and perceived behavioral control can boost the intention to be vaccinated and facilitate the uptake of COVID-19 vaccination.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Intención , Estudiantes , Vacunación , Humanos , Femenino , Estudiantes/psicología , Masculino , Adulto Joven , Universidades , COVID-19/prevención & control , COVID-19/psicología , Vacunas contra la COVID-19/administración & dosificación , Encuestas y Cuestionarios , Adulto , Vacunación/psicología , SARS-CoV-2/aislamiento & purificación , Conductas Relacionadas con la Salud , Conocimientos, Actitudes y Práctica en Salud , Teoría Psicológica , Teoría del Comportamiento Planificado
4.
J Prev Med Public Health ; 55(6): 506-519, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36475316

RESUMEN

OBJECTIVES: This study aimed to analyze the associations of income, marital status, and health behaviors with hypertension in male and female over 40 years of age in the Korea. METHODS: The data were derived from the Korean Genome and Epidemiology Study (KoGES; 4851-302) which included 211 576 participants. To analyze the relationships of income, marital status, and health behaviors with hypertension in male and female over 40 years of age, multiple logistic regression was conducted with adjustments for these variables. RESULTS: The prevalence of hypertension increased linearly as income decreased. The odds ratio for developing hypertension in people with an income of <0.5 million Korean won (KRW) compared to ≥6.0 million KRW was 1.55 (95% confidence interval [CI], 1.25 to 1.93) in the total population, 1.58 (95% CI, 1.27 to 1.98) in male, and 1.07 (95% CI, 0.35 to 3.28) in female. The combined effect of income level and marital status on hypertension was significant. According to income level and marital status, in male, low income and divorce were most associated with hypertension (1.76 times; 95% CI, 1.01 to 3.08). However, in female, the low-income, married group was most associated with hypertension (1.83 times; 95% CI, 1.71 to 1.97). CONCLUSIONS: The results of this study show that it is necessary to approach male and female marital status separately according to income in health policies to address inequalities in the prevalence of hypertension.


Asunto(s)
Hipertensión , Pobreza , Humanos , Femenino , Masculino , Adulto , Persona de Mediana Edad , Estado Civil , Matrimonio , Política de Salud , Hipertensión/epidemiología
5.
Int J Pharm ; 574: 118893, 2020 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-31765773

RESUMEN

Combination therapy, a treatment regimen that combines more than two therapeutic agents to diseased tissues has recently gained increasing attentions in anticancer therapy. As cancer cells are more vulnerable to oxidative stress and heat compared to normal cells, we developed hyperthermia- and oxidative stress-inducing maltodextrin (HTOM) nanoparticles as a platform of combinational photothermal/oxidative anticancer therapy. HTOM was designed to incorporate cinnamaldehyde as an oxidative stress inducer through acid-labile acetal linkage and IR780 as a photoabsorber. HTOM nanoparticles could generate excess reactive oxygen species (ROS) to kill cancer cells effectively. When exposed to near infrared (NIR) laser irradiation (808 nm), HTOM nanoparticles also increased temperature to destroy cancer cells. The combination of NIR laser irradiation with HTOM nanoparticles exhibited significantly higher anticancer activity than HTOM nanoparticles alone and NIR lasers irradiation alone. When combined with NIR laser irradiation on the tumor site, intravenously administrated HTOM nanoparticles effectively eradicated tumors in mouse xenograft models. Our strategy for combination of oxidative stress and photothermal heating may offer a new combinational treatment modality for cancer.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Nanopartículas/química , Estrés Oxidativo/efectos de los fármacos , Polisacáridos/química , Células A549 , Acroleína/análogos & derivados , Acroleína/química , Animales , Línea Celular Tumoral , Terapia Combinada/métodos , Portadores de Fármacos/química , Humanos , Hipertermia Inducida/métodos , Ratones , Fototerapia/métodos , Polisacáridos/farmacología , Células RAW 264.7 , Especies Reactivas de Oxígeno/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
6.
Genomics Inform ; 18(3): e33, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33017877

RESUMEN

This paper describes a community effort to improve earlier versions of the full-text corpus of Genomics & Informatics by semi-automatically detecting and correcting PDF-to-text conversion errors and optical character recognition errors during the first hackathon of Genomics & Informatics Annotation Hackathon (GIAH) event. Extracting text from multi-column biomedical documents such as Genomics & Informatics is known to be notoriously difficult. The hackathon was piloted as part of a coding competition of the ELTEC College of Engineering at Ewha Womans University in order to enable researchers and students to create or annotate their own versions of the Genomics & Informatics corpus, to gain and create knowledge about corpus linguistics, and simultaneously to acquire tangible and transferable skills. The proposed projects during the hackathon harness an internal database containing different versions of the corpus and annotations.

7.
ACS Omega ; 4(6): 10070-10077, 2019 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-31460099

RESUMEN

A main challenge in the development of anticancer drugs that eradicate cancer cells specifically with minimal toxicity to normal cells is to identify the cancer-specific properties. Cancer cells sustain a higher level of reactive oxygen species, owing to metabolic and signaling aberrations and unrestrained growth. Cancer cells are also furnished with a powerful reducing environment, owing to the overproduction of antioxidants such as glutathione (GSH). Therefore, the altered redox balance is probably the most prevailing property of cancer cells distinct from normal cells, which could serve as a plausible therapeutic target. In this work, we developed a GSH-depleting pro-oxidant, benzoyloxy dibenzyl carbonate, termed B2C, which is capable of rapidly declining GSH and elevating oxidative stress to a threshold level above which cancer cells cannot survive. B2C was designed to release quinone methide (QM) that rapidly depletes GSH through esterase-mediated hydrolysis. B2C was able to rapidly deplete GSH and induce an overwhelming level of oxidative stress in cancer cells, leading to mitochondrial disruption, activation of procaspase-3 and PARP-1, and cleavage of Bcl-2. In the study of tumor xenograft models, intravenously injected B2C caused apoptotic cell death in tumors and significantly suppressed tumor growth. These findings provide a new insight into the design of more effective anticancer drugs, which exploit altered redox balance in cancer cells.

8.
J Biomed Mater Res A ; 76(2): 252-63, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16265638

RESUMEN

Successful reconstruction of large-diameter blood vessel in humans has been demonstrated using the tissue engineering technique, but improvement in patency of small-diameter bioartificial vascular graft remains a great challenge. This study reports that granulocyte colony-stimulating factor (G-CSF) can enhance in vivo endothelialization of tissue-engineered vascular grafts, which could be used to improve patency of small-diameter vascular graft. Vascular grafts were tissue engineered with decellularized canine abdominal aortas and canine autologous bone marrow-derived cells. Prior to cell seeding onto decellularized graft matrices, bone marrow-derived cells were induced to differentiate into endothelial cells and smooth muscle cells. The cell-seeded vascular grafts were implanted into the abdominal aortas of bone marrow donor dogs. Before and after graft implantation, G-CSF was administered subcutaneously to the dogs (n = 3). The grafts implanted into the dogs not receiving G-CSF were used as controls (n = 3). Eight weeks after implantation, grafts in both groups showed regeneration of vascular tissues including endothelium and smooth muscle. Importantly, endothelium formation was more extensive in the G-CSF-treated grafts than in the control grafts, as assessed with reverse transcription polymerase chain reaction, western blot, and immunohistochemistry. In addition, intimal hyperplasia was significantly reduced in the G-CSF-treated grafts compared to the control grafts. This study suggests that G-CSF administration could be applied to improve patency of small-diameter tissue-engineered vascular grafts.


Asunto(s)
Prótesis Vascular , Factor Estimulante de Colonias de Granulocitos/farmacología , Regeneración/efectos de los fármacos , Ingeniería de Tejidos/métodos , Animales , Aorta , Células de la Médula Ósea/citología , Diferenciación Celular , Perros , Células Endoteliales/citología , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Miocitos del Músculo Liso/citología , Implantación de Prótesis
9.
Ann Dermatol ; 23(4): 455-62, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22148012

RESUMEN

BACKGROUND: Hair dryers are commonly used and can cause hair damage such as roughness, dryness and loss of hair color. It is important to understand the best way to dry hair without causing damage. OBJECTIVE: The study assessed changes in the ultra-structure, morphology, moisture content, and color of hair after repeated shampooing and drying with a hair dryer at a range of temperatures. METHODS: A standardized drying time was used to completely dry each hair tress, and each tress was treated a total of 30 times. Air flow was set on the hair dryer. The tresses were divided into the following five test groups: (a) no treatment, (b) drying without using a hair dryer (room temperature, 20℃), (c) drying with a hair dryer for 60 seconds at a distance of 15 cm (47℃), (d) drying with a hair dryer for 30 seconds at a distance of 10 cm (61℃), (e) drying with a hair dryer for 15 seconds at a distance of 5 cm (95℃). Scanning and transmission electron microscopy (TEM) and lipid TEM were performed. Water content was analyzed by a halogen moisture analyzer and hair color was measured with a spectrophotometer. RESULTS: Hair surfaces tended to become more damaged as the temperature increased. No cortex damage was ever noted, suggesting that the surface of hair might play a role as a barrier to prevent cortex damage. Cell membrane complex was damaged only in the naturally dried group without hair dryer. Moisture content decreased in all treated groups compared to the untreated control group. However, the differences in moisture content among the groups were not statistically significant. Drying under the ambient and 95℃ conditions appeared to change hair color, especially into lightness, after just 10 treatments. CONCLUSION: Although using a hair dryer causes more surface damage than natural drying, using a hair dryer at a distance of 15 cm with continuous motion causes less damage than drying hair naturally.

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