Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
1.
Small ; : e2310283, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38227378

RESUMO

Conventional hydrogel microcapsules often suffer from inadequate mechanical stability, hindering their use. Here, water-cored double-network (DN) hydrogel shells are designed, formed by polyacrylamide and calcium alginate networks using triple-emulsion templates. These DN hydrogel shells offer robust mechanical stability, optical transparency, and a precisely-defined cut-off threshold. The feasibility of this platform is demonstrated through the development of a fluorometric glucose sensor. Glucose oxidase is enclosed within the water core, while a pH-responsive fluorescent dye is incorporated into the DN shells. Glucose diffuses into the core through the DN shells, where the glucose oxidase converts glucose into gluconic acid, leading to pH reduction and a subsequent decrease in fluorescence intensity of DN shells. Additionally, the pH-sensitive colorant dissolved in the medium enables visual pH assessment. Thus, glucose levels can be determined using both fluorometric and colorimetric methods. Notably, the DN shells exhibit exceptional stability, enduring intense mechanical stress and cycles of drying and rehydration without leakage. Moreover, the DN shells act as effective barriers, safeguarding glucose oxidase against proteolysis by large disruptive proteins, like pancreatin. This versatile DN shell platform extends beyond glucose oxidase encapsulation, serving as a foundation for various capsule sensors utilizing enzymes and heterogeneous catalysts.

2.
J Korean Med Sci ; 37(45): e332, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-36413800

RESUMO

BACKGROUND: It remains unclear whether coffee intake is associated with the risk of hypertension. This study aimed to investigate the association between coffee intake and the risk of hypertension by using a meta-analysis of cohort studies. METHODS: PubMed and Embase were searched using keywords in September 2022 to identify studies on coffee intake and the risk of hypertension. RESULTS: We included a total of 13 longitudinal cohort studies, which involved a total of 64,650 incident cases of hypertension among 314,827 participants. In a random effects model meta-analysis of all the studies, coffee intake was not significantly associated with the risk of hypertension (relative risk [RR], 0.97; 95% confidence interval [CI], 0.90­1.05; I² = 58.0%; n = 13). In the subgroup meta-analysis, coffee intake was associated with a decreased risk of hypertension in studies conducted in America (RR, 0.93; 95% CI, 0.87-0.98; I² = 4.6%; n = 5) and in low-quality studies (RR, 0.92; 95% CI, 0.88-0.96; I² = 0.0%; n = 7). In the remaining subgroup meta-analyses by amount of coffee intake, gender, type of coffee (decaffeinated vs. caffeinated), smoking, and years of follow-up, coffee intake was not significantly associated with the risk of hypertension. CONCLUSION: The current meta-analysis showed that coffee intake is not associated with the risk of hypertension.


Assuntos
Café , Hipertensão , Humanos , Café/efeitos adversos , Cafeína , Estudos Longitudinais , Estudos de Coortes , Hipertensão/epidemiologia , Hipertensão/etiologia
3.
Lab Chip ; 22(12): 2259-2291, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35608122

RESUMO

Multiple-emulsion drops serve as versatile templates to design functional microcapsules due to their core-shell geometry and multiple compartments. Microfluidics has been used for the elaborate production of multiple-emulsion drops with a controlled composition, order, and dimensions, elevating the value of multiple-emulsion templates. Moreover, recent advances in the microfluidic control of the emulsification and parallelization of drop-making junctions significantly enhance the production throughput for practical use. Metastable multiple-emulsion drops are converted into stable microcapsules through the solidification of selected phases, among which solid shells are designed to function in a programmed manner. Functional microcapsules are used for the storage and release of active materials as drug carriers. Beyond their conventional uses, microcapsules can serve as microcompartments responsible for transmembrane communication, which is promising for their application in advanced microreactors, artificial cells, and microsensors. Given that post-processing provides additional control over the composition and construction of multiple-emulsion drops, they are excellent confining geometries to study the self-assembly of colloids and liquid crystals and produce miniaturized photonic devices. This review article presents the recent progress and current state of the art in the microfluidic production of multiple-emulsion drops, functionalization of solid shells, and applications of microcapsules.


Assuntos
Portadores de Fármacos , Microfluídica , Cápsulas/química , Portadores de Fármacos/química , Emulsões/química
4.
Cancer Res Treat ; 54(3): 907-916, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34665955

RESUMO

PURPOSE: This study aimed to compare the early hematological dynamics and acute toxicities between proton beam craniospinal irradiation (PrCSI) and photon beam craniospinal irradiation (PhCSI) for pediatric brain tumors. MATERIALS AND METHODS: We retrospectively reviewed patients with pediatric brain tumors who received craniospinal irradiation (CSI). The average change in hemoglobin levels (ΔHbavg), absolute lymphocyte counts (ΔALCavg), and platelet counts (ΔPLTavg) from baseline values was evaluated and compared between the PrCSI and PhCSI groups at 1 and 2 weeks after the initiation of CSI, 1 week before and at the end of radiotherapy, and 3-4 weeks after the completion of radiotherapy using t test and mixed-model analysis. RESULTS: The PrCSI and PhCSI groups consisted of 36 and 30 patients, respectively. There were no significant differences in ΔHbavg between the two groups at any timepoint. However, ΔALCavg and ΔPLTavg were significantly lower in the PhCSI group than in PrCSI group at every timepoint, demonstrating that PrCSI resulted in a significantly lower rate of decline and better recovery of absolute lymphocyte and platelet counts. The rate of grade 3 acute anemia was significantly lower in the PrCSI group than in in the PhCSI group. CONCLUSION: PrCSI showed a lower rate of decline and better recovery of absolute lymphocyte and platelet counts than PhCSI in the CSI for pediatric brain tumors. Grade 3 acute anemia was significantly less frequent in the PrCSI group than in the PhCSI group. Further large-scale studies are warranted to confirm these results.


Assuntos
Anemia , Neoplasias Encefálicas , Radiação Cranioespinal , Neoplasias Encefálicas/radioterapia , Criança , Radiação Cranioespinal/efeitos adversos , Radiação Cranioespinal/métodos , Humanos , Prótons , Dosagem Radioterapêutica , Estudos Retrospectivos
5.
Radiother Oncol ; 146: 187-193, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32179362

RESUMO

BACKGROUND AND PURPOSE: Our study aimed to compare the oncologic outcomes and toxicities between passive scattering (PS) proton beam therapy (PBT) and pencil-beam scanning (PBS) PBT for primary hepatocellular carcinoma (HCC). MATERIALS AND METHODS: The multidisciplinary team for liver cancer identified the PBT candidates who were ineligible for resection or radiofrequency ablation. We retrospectively analyzed 172 patients who received PBT for primary HCC from January 2016 to December 2017. The PS with wobbling method was applied with both breath-hold and regular breathing techniques, while the PBS method was utilized only for regular breathing techniques covering the full amplitude of respiration. To maintain the balance of the variables between the PS and PBS groups, we performed propensity score matching. RESULTS: The median follow-up duration for the total cohort was 14 months (range, 1-31 months). After propensity score matching, a total of 103 patients (70 in the PS group and 33 in the PBS group) were included in analysis. There were no significant differences in the rates of overall survival (OS), in-field local control (IFLC), out-field intrahepatic control (OFIHC), extrahepatic progression-free survival (EHPFS), and complete response (CR) between the matched groups. In the subgroup analyses, no subgroup showed a significant difference in IFLC between the PS and PBS groups. There was also no significant difference in the toxicity profiles between the groups. CONCLUSION: There are no differences in oncologic outcomes, including OS, IFLC, OFIHC, EHPFS, and CR rates, or in the toxicity profiles between PS and PBS PBT for primary HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Terapia com Prótons , Carcinoma Hepatocelular/radioterapia , Humanos , Neoplasias Hepáticas/radioterapia , Pontuação de Propensão , Terapia com Prótons/efeitos adversos , Estudos Retrospectivos
6.
Sensors (Basel) ; 18(9)2018 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-30134526

RESUMO

The patient's respiratory pattern and reproducibility are important factors affecting the accuracy of radiotherapy for lung cancer or liver cancer cases. Therefore, respiration training is required to induce respiration regularity before radiotherapy. However, the need for specialized personnel, space, and time-consuming training represent limitations. To solve these problems, we have developed a respiratory monitoring and training system based on a micro-electro-mechanical-system (MEMS) magnetic sensor. This system consists of a small attaching magnet, a sensor, and a breathing pattern output device. In this study, we evaluated the performance of the signal measurement in the developed system based on the various respiratory cycles, the amplitudes, and the position angles of the magnet and the sensor. The system can provide a more accurate breathing signal graph with lower measurement error and higher spatial resolution than conventional sensor methods by using additional magnet. In addition, it is possible the patient to monitor and train breathing himself by making it easy to carry and use without restriction of time and space.


Assuntos
Desenho de Equipamento , Campos Magnéticos , Sistemas Microeletromecânicos , Monitorização Fisiológica/instrumentação , Radioterapia/métodos , Respiração , Humanos , Reprodutibilidade dos Testes
7.
Health Phys ; 114(1): 77-83, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29135537

RESUMO

This study was conducted as part of an endeavor to improve the risk management system of radiation therapy departments in the Republic of Korea. An online survey on the status and perception of Korea's medical physicists on risk management in radiation therapy was carried out. A total of 40 domestic radiation oncology departments participated. This survey is divided into three categories: (1) work environment; (2) risk management status; and (3) opinions on how to improve risk management. Based on the results of the survey, the conclusions that can be derived are (1) the majority of respondents have a high interest in the risk management of radiation therapy; (2) the lack of staffing is one cause of risk management difficulties; (3) a risk-related terminology and classification system at the national or professional association level are required; (4) each hospital should create a voluntary reporting system for the handling of incidents; (5) medical physicists should establish incident reporting, analysis and countermeasures; and (6) government should develop education and training programs. It was confirmed that the current risk management system should be changed by education in the hospital and at the national level in order to improve risk management related to radiation therapy. In addition, it was recognized that a dedicated staff and a risk management certification system and organization for patient safety in radiotherapy are needed.


Assuntos
Atitude do Pessoal de Saúde , Física Médica , Radioterapia/métodos , Radioterapia/normas , Gestão de Riscos , Gestão da Segurança , Hospitais , Humanos , Segurança do Paciente , Garantia da Qualidade dos Cuidados de Saúde , República da Coreia , Inquéritos e Questionários , Recursos Humanos
8.
Med Phys ; 40(2): 021704, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23387727

RESUMO

PURPOSE: To evaluate the accuracy of measuring volumes using three-dimensional ultrasound (3D US), and to verify the feasibility of the replacement of CT-MR fusion images with CT-3D US in radiotherapy treatment planning. METHODS: Phantoms, consisting of water, contrast agent, and agarose, were manufactured. The volume was measured using 3D US, CT, and MR devices. A CT-3D US and MR-3D US image fusion software was developed using the Insight Toolkit library in order to acquire three-dimensional fusion images. The quality of the image fusion was evaluated using metric value and fusion images. RESULTS: Volume measurement, using 3D US, shows a 2.8 ± 1.5% error, 4.4 ± 3.0% error for CT, and 3.1 ± 2.0% error for MR. The results imply that volume measurement using the 3D US devices has a similar accuracy level to that of CT and MR. Three-dimensional image fusion of CT-3D US and MR-3D US was successfully performed using phantom images. Moreover, MR-3D US image fusion was performed using human bladder images. CONCLUSIONS: 3D US could be used in the volume measurement of human bladders and prostates. CT-3D US image fusion could be used in monitoring the target position in each fraction of external beam radiation therapy. Moreover, the feasibility of replacing the CT-MR image fusion to the CT-3D US in radiotherapy treatment planning was verified.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/radioterapia , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos , Humanos , Masculino , Tamanho do Órgão , Imagens de Fantasmas , Neoplasias da Próstata/patologia , Sensibilidade e Especificidade , Carga Tumoral
9.
J Pediatr Endocrinol Metab ; 25(3-4): 279-84, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22768657

RESUMO

BACKGROUND: The growth assessment of bone age (BA) is an essential feature in diagnosing various diseases in children. In the clinic, the Tanner and Whitehouse (TW3) method and the Greulich-Pyle (GP) method are used to estimate bone age. Because those methods were developed for foreign children, it is necessary to evaluate the applicability of those methods to Koreans. OBJECTIVES: This study was designed (1) to compare the skeletal maturity score (SMS) in Koreans to the SMS in foreign children, and (2) to establish a correlation between the BA and chronological age (CA) on the basis of gender and age in normal Korean children. MATERIAL AND METHODS: We estimated the SMS and BA for 378 healthy children (141 boys and 237 girls) who visited the pediatrics clinic in Ewha Womans University Mokdong Hospital (Seoul, Korea) from 2000 to 2009. The SMS and BA were estimated using the TW3 and GP methods. RESULTS: The SMS in Koreans was higher than in foreign children, and on average, the BA measured by both methods was higher than the CA. The correlation between the BA and CA were different according to gender and age. CONCLUSIONS: We suggest that there are differences between the SMS in Korean and foreign children and between the BA and CA. Therefore, the results can be used in evaluating the skeletal maturity of Koreans, and a correlation between the BA and CA would be a useful reference in diagnosis.


Assuntos
Determinação da Idade pelo Esqueleto/métodos , Povo Asiático/estatística & dados numéricos , Desenvolvimento Ósseo/fisiologia , Adolescente , Criança , Feminino , Humanos , Masculino
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA