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1.
Curr Med Imaging ; 19(11): 1337-1345, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36703587

RESUMEN

BACKGROUND: Diagnostic accuracy of double-contrast barium enema (DCBE) depends upon the barium sulfate coating efficiency in the colon. OBJECTIVE: To evaluate effects of three laxatives on barium sulfate coating efficiency in the large intestine, sigmoid colon, and hepatic flexure in DCBE. METHODS: This retrospective study included patients receiving DCBE after pre-procedure cleansing with Dulcolax® with castor oil (DC), Klean-Prep® (KP), or Fleet® . Patients' DCBE images were reviewed. RESULTS: Among 373 cases of DCBE, 151 received DC, 147 received KP, and 75 received Fleet. For DCBE, the optimal extent of barium sulfate residue coated on the wall of the large intestine is less than one-fourth of bowel wall width; the DC group had a higher percentage of less than one-fourth of bowel wall than that of the KP or Fleet group (both p < 0.0167). DC, KP and Fleet have comparable barium sulfate coating efficiency in the sigmoid colon. However, in the hepatic flexure, the DC group had a higher percentage of barium sulfate coating without interruption than that of the KP or Fleet groups (both p < 0.0167). CONCLUSION: DC has a better barium sulfate coating efficiency in the hepatic flexure compared with KP and Fleet.


Asunto(s)
Sulfato de Bario , Laxativos , Humanos , Enema Opaco , Estudios Retrospectivos , Radiografía , Enema/métodos
2.
J Dent Sci ; 17(4): 1544-1552, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36299339

RESUMEN

Background/purpose: The development of dental radiology in Taiwan has been over a century. This study explored mainly the profile of dental radiation workers and their occupational radiation exposure in Taiwan from 2013 to 2020. Materials and methods: This study used the secondary data analysis to survey mainly the changes of manpower of the dental radiation workers and their occupational radiation exposure in Taiwan from 2013 to 2020. Results: The number of monitored dental radiation workers increased from 678 in 2013 to 770 in 2020. However, the proportion of monitored dental radiation workers to the total monitored medical radiation workers decreased from 4.29% in 2013 to 3.67% in 2020. Although the number of monitored dental radiation workers increased, the number of the measurably exposed dental radiation workers decreased from 2013 to 2020. The annual collective exposure dose fluctuated from 5.21 man-Sv to 15.47 man-Sv, but it showed a decreasing trend. Furthermore, the mean annual effective exposure dose of total monitored dental radiation workers (0.01-0.02 mSv) and that of the measurably exposed dental radiation workers (0.15-1.11 mSv) were relatively low among various medical radiation workers. In overall, the proportion of medical radiation technologists to dentists varied from 0.41 to 0.45. Conclusion: Although the number of monitored dental radiation workers increase, the number of the measurably exposed dental radiation workers, the proportion of the measurably exposed dental radiation workers to the total monitored dental radiation workers, and the annual collective exposure dose for monitored dental radiation workers decrease from 2013 to 2020.

3.
J Xray Sci Technol ; 30(4): 657-666, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35367977

RESUMEN

BACKGROUND: Medical imaging plays a crucial role in modern medicine. In order to provide fast and accurate medical diagnosis, computed tomography (CT) is a commonly used tool in radiological examinations, and 640-slice CT is the most advanced CT imaging modality. OBJECTIVE: To evaluate the radiation dose and the risk under 640-slice abdominal CT examination. METHODS: Examinations were performed using a 640-slice CT scanner on an Alderson-Rando anthropomorphic phantom. The used scanning acquisition parameters were the same as those used on abdominal examination without contrast medium injection in clinical practice. To measure the absorbed doses, optically stimulated luminescence dosimeters (OSLDs) were put into liver, stomach, bladder, gonads, colon, small intestine, bone marrow, and skin. RESULTS: According to the 1990 Recommendations of the International Commission on Radiological Protection (ICRP Publication 60), the calculated effective doses received from this examination were 0.90 mSv in males and 0.89 mSv in females. According to the 2007 Recommendations of the International Commission on Radiological Protection (ICRP Publication 103), the calculated effective dose received from this examination was 0.83 mSv in both sexes. CONCLUSIONS: Radiation doses obtained from the abdominal 640-slice CT examination are lower than the yearly cumulative doses received from natural radiation, revealing there is no deterministic effect and radiation risk is relatively low; therefore, this CT examination is considered safe.


Asunto(s)
Protección Radiológica , Tomografía Computarizada por Rayos X , Femenino , Humanos , Masculino , Fantasmas de Imagen , Dosis de Radiación , Tomógrafos Computarizados por Rayos X
4.
Biomed Res Int ; 2021: 9985714, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34671681

RESUMEN

BACKGROUND: Radiation using conventional X-ray is associated with exposure of radiosensitive organs and typically requires the use of protection. This study is aimed at evaluating the use of bismuth shielding for radiation protection in pediatric pelvic radiography. The effects of the anteroposterior and lateral bismuth shielding were verified by direct measurements at the anatomical position of the gonads. METHODS: Radiation doses were measured using optically stimulated luminescence dosimeters (OSLD) and CIRS ATOM Dosimetry Verification Phantoms. Gonad radiographs were acquired using different shields of varying material (lead, bismuth) and thickness and were compared with radiographs obtained without shielding to examine the effects on image quality and optimal reduction of radiation dose. All images were evaluated separately by three pediatric orthopedic practitioners. RESULTS: Results showed that conventional lead gonadal shielding reduces radiation doses by 67.45%, whereas dose reduction using one layer of bismuth shielding is 76.38%. The use of two layers of bismuth shielding reduces the dose by 84.01%. Using three and four layers of bismuth shielding reduces dose by 97.33% and 99.34%, respectively. Progressively lower radiation doses can be achieved by increasing the number of bismuth layers. Images obtained using both one and two layers of bismuth shielding provided adequate diagnostic information, but those obtained using three or four layers of bismuth shielding were inadequate for diagnosis. CONCLUSIONS: Bismuth shielding reduces radiation dose exposure providing appropriate protection for children undergoing pelvic radiography. The bismuth shielding material is lighter than lead, making pediatric patients more comfortable and less apt to move, thereby avoiding repeat radiography.


Asunto(s)
Bismuto/química , Pelvis/efectos de la radiación , Protección Radiológica/métodos , Niño , Humanos , Fantasmas de Imagen , Dosis de Radiación , Exposición a la Radiación/prevención & control , Protección Radiológica/instrumentación , Tomografía Computarizada por Rayos X , Rayos X
5.
Anticancer Res ; 41(6): 2867-2874, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34083277

RESUMEN

BACKGROUND/AIM: Non-small cell lung cancer (NSCLC) is the most common type of lung cancer with poor prognosis. Lenvatinib is a multi-kinase inhibitor that has the potential to suppress tumor progression. Our previous study suggested that lenvatinib induces cytotoxicity and apoptosis in CL-1-5-F4 cells in vitro. However, whether lenvatinib suppresses NSCLC progression in vivo remains unclear. MATERIALS AND METHODS: Tumor growth inhibition and normal tissue toxicity evaluation following lenvatinib treatment were performed on CL-1-5-F4-bearing mice. RESULTS: Tumor growth calculated by caliper and living cell intensity decreased by lenvatinib treatment as analysed by bioluminescence imaging. Phosphorylation of AKT, NF-κB, and NF-κB downstream proteins involved in tumor progression were reduced by lenvatinib in the tumor tissue. No pathological changes were found in the liver, kidney, and spleen after lenvatinib treatment. CONCLUSION: Induction of apoptosis and suppression of AKT/NF-κB were associated with lenvatinib-induced inhibition of the progression of NSCLC in vivo.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/patología , FN-kappa B/antagonistas & inhibidores , Compuestos de Fenilurea/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Quinolinas/farmacología , Transducción de Señal/efectos de los fármacos , Animales , Carcinoma de Pulmón de Células no Pequeñas/enzimología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Progresión de la Enfermedad , Humanos , Neoplasias Pulmonares/enzimología , Neoplasias Pulmonares/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Ensayos Antitumor por Modelo de Xenoinjerto
6.
J Xray Sci Technol ; 29(4): 617-633, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33967076

RESUMEN

The Tc-99m methylene diphosphonate (MDP) whole body bone scan (WBBS) has been widely accepted as a method of choice for the initial diagnosis of bone and joint changes in patients with oncologic diseases. The WBBS has shown high sensitivity but relatively low specificity due to bone variation. This study aims to use the self-developing irregular flux viewer (IFV) system to predict possible bone lesions in planar WBBS. The study uses gradient vector flow (GVF) and self-organizing map (SOM) methods to analyze the blood fluid-dynamics and evaluate hot points. The evaluation includes a selection of 368 patients with bone metastasis from prostate cancer, lung cancer and breast cancer. Finally, we compare IFV values with BONENAVI version data. BONENAVI is a computer-assisted diagnosis system that analyzes bone scintigraphy automatically. The analysis shows that the IFV system achieves sensitivities of 93% for prostate cancer, 91% for breast cancer, and 83% for lung cancer, respectively. On the other hand, our proposed approach achieves a higher sensitivity than the results of BONEVAVI version 2.0.5 for prostate cancer (88%), breast cancer (86%) and lung cancer (82%), respectively. The study results demonstrate that the high sensitivity and specificity of the IFV system can provide assistance for image interpretation and generate prediction values for WBBS.


Asunto(s)
Neoplasias Óseas , Neoplasias de la Próstata , Neoplasias Óseas/diagnóstico por imagen , Huesos/patología , Diagnóstico por Computador/métodos , Humanos , Masculino , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Sensibilidad y Especificidad , Medronato de Tecnecio Tc 99m
7.
Anticancer Res ; 35(7): 3867-73, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26124332

RESUMEN

The study goal was to evaluate the effects of curcumin on DNA damage and expression of DNA-repair proteins in human lung cancer. Thus, NCI-H460 cells were used to study the effects of curcumin on DNA damage and repair in vitro. We investigated curcumin induces DNA damage by comet the assay and 4',6-diamidino-2-phenylindole (DAPI) staining. The DNA damage/repair-related protein levels were examined and monitored by western blotting and confocal microscopy. Curcumin significantly increased the length of comet tails and DNA condensation in NCI-H460 cells. Curcumin reduced expression of DNA-repair proteins such as 14-3-3 protein sigma (14-3-3σ), O6-methylguanine-DNA methyltransferase (MGMT), breast cancer susceptibility gene 1 (BRCA1), and mediator of DNA damage checkpoint 1 (MDC1). Curcumin also increased phosphorylation of p53 and Histone H2A.X (S140) in the nuclei of NCI-H460 cells. Taken together, our findings indicated that curcumin triggered DNA damage and inhibited expression of DNA-repair-associated proteins in NCI-H460 cells.


Asunto(s)
Curcumina/farmacología , Daño del ADN/efectos de los fármacos , Reparación del ADN/efectos de los fármacos , Proteínas de Unión al ADN/genética , Neoplasias Pulmonares/genética , Línea Celular Tumoral , Reparación del ADN/genética , Humanos , Fosforilación/efectos de los fármacos , Fosforilación/genética , Proteína p53 Supresora de Tumor/genética
8.
Health Phys ; 109(2): 171-6, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26107437

RESUMEN

Industrial radiography is a common nondestructive testing (NDT) method used in various industries. An investigation was conducted for a 1999 incident in Taiwan where two workers (Operators A and B) were accidently exposed to an unshielded Ir source while conducting industrial radiography. Operators A and B experienced acute close-range radiation exposure to a source of Ir for 3 h at a strength of 2.33 × 10 Bq. The health of mammary glands, bone marrow, thyroid glands, eyes, and genital organs of these two workers after radiation exposure was examined. Subsequently, Operator A experienced severe radiation injury, including tissue necrosis and keratinization in the fingers, chromosomal abnormalities, reduced blood cell count, diffuse hyperplasia of the thyroid gland, opaque spots in the crystalline lens, and related radiation effects. The results showed that the left index finger and thumb, eyes, and gonads of Operator A were exposed to a radiation dose of about 369-1,070, 23.1-67.4, 2.4-5.3, and 4.2-11.6 Gy, respectively. Effective dose for Operator A was estimated to range from 6.9 to 18.9 Sv. The left fingers, thumb, eyes, and gonads of Operator B were exposed to a radiation dose of 184.9-646.2, 11.8-40.7, 0.49-3.33, and 0.72-7.18 Gy, respectively, and his effective dose was between 2.5 and 11.5 Sv. This accident indicated a major flaw in the control and regulation of radiation safety for conducting NDT industrial radiography in 1999; however, similar problems still exist. Modifications of the Ionizing Radiation Protection Act in Taiwan are suggested in this study to regulate the management of NDT industries, continually educate the NDT workers in radiation safety, and enact notification provisions for medical care systems toward acute radiation exposure events.


Asunto(s)
Exposición Profesional , Liberación de Radiactividad Peligrosa , Humanos , Dosis de Radiación , Protección Radiológica/legislación & jurisprudencia , Radiografía/efectos adversos , Taiwán
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