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1.
Antioxidants (Basel) ; 10(8)2021 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-34439567

RESUMO

Previous studies indicate that bilberry with high amounts of phenolic compounds can inhibit carcinogenic processes of colorectal cancer in vitro and in vivo. However, no studies have focused on the effects of bilberry on oral cancer. In this study, we aimed to examine the effects of bilberry powder on oral squamous cell carcinoma (OSCC) cells using both in vitro and in vivo assays. The effects of 0, 1, 10, and 25 mg/mL of whole bilberry powder on the viability, proliferation, migration, and invasion of OSCC (HSC-3) cells were examined and compared with 0.01 mg/mL of cetuximab. Two oral keratinocyte cell lines served as controls. Tumor area was analyzed in zebrafish microinjected with HSC-3 cells and treated with 2.5, 10, or 25 µg/mL of bilberry powder. Metastases in the head or tail areas were counted. Bilberry powder inhibited the viability, proliferation, migration, and invasion of HSC-3 cells (p < 0.05), which was more pronounced with higher concentrations. Cetuximab had no effect on HSC-3 cell migration or invasion. Compared to controls, the tumor area in zebrafish treated with bilberry powder (10 and 25 µg/mL) was reduced significantly (p = 0.038 and p = 0.021, respectively), but the number of fish with metastases did not differ between groups. Based on our in vitro and in vivo experiments, we conclude that whole bilberry powder has anti-tumor effects on OSCC cells.

2.
Pediatr Radiol ; 45(10): 1544-53, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25939873

RESUMO

BACKGROUND: Medical professionals need to exercise particular caution when developing CT scanning protocols for children who require multiple CT studies, such as those with craniosynostosis. OBJECTIVE: To evaluate the utility of ultra-low-dose CT protocols with model-based iterative reconstruction techniques for craniosynostosis imaging. MATERIALS AND METHODS: We scanned two pediatric anthropomorphic phantoms with a 64-slice CT scanner using different low-dose protocols for craniosynostosis. We measured organ doses in the head region with metal-oxide-semiconductor field-effect transistor (MOSFET) dosimeters. Numerical simulations served to estimate organ and effective doses. We objectively and subjectively evaluated the quality of images produced by adaptive statistical iterative reconstruction (ASiR) 30%, ASiR 50% and Veo (all by GE Healthcare, Waukesha, WI). Image noise and contrast were determined for different tissues. RESULTS: Mean organ dose with the newborn phantom was decreased up to 83% compared to the routine protocol when using ultra-low-dose scanning settings. Similarly, for the 5-year phantom the greatest radiation dose reduction was 88%. The numerical simulations supported the findings with MOSFET measurements. The image quality remained adequate with Veo reconstruction, even at the lowest dose level. CONCLUSION: Craniosynostosis CT with model-based iterative reconstruction could be performed with a 20-µSv effective dose, corresponding to the radiation exposure of plain skull radiography, without compromising required image quality.


Assuntos
Craniossinostoses/diagnóstico por imagem , Imagens de Fantasmas , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Artefatos , Pré-Escolar , Humanos , Recém-Nascido , Razão Sinal-Ruído
3.
Pediatr Radiol ; 43(6): 673-84, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23341090

RESUMO

BACKGROUND: CT optimization has a special importance in children. Smaller body size accentuates the importance of patient positioning affecting both radiation dose and image quality. OBJECTIVE: To determine the effect of vertical positioning on organ dose, image noise and contrast in pediatric chest CT examination. MATERIALS AND METHODS: Chest scans of a pediatric 5-year anthropomorphic phantom were performed in different vertical positions (-6 cm to +5.4 cm) with a 64-slice CT scanner. Organ doses were measured with metal-oxide-semiconductor field-effect transistor (MOSFET) dosimeters. Image noise and contrast were determined from the CT number histograms corresponding to different tissues. RESULTS: Significant changes in organ doses resulting from vertical positioning were observed, especially in radiosensitive anterior organs. The breast dose increased up to 16% and the thyroid dose up to 24% in lower positions. The noise was increased up to 45% relative to the centre position in the highest and lowest vertical positions, with a particular increase observed on the anterior and posterior sides, respectively. Off-centering also affected measured image contrast. CONCLUSION: Vertical off-centering markedly affects organ doses and measured image-quality parameters in pediatric chest CT examination. Special attention should be given to correct patient centering when preparing patients for CT scans, especially when imaging children.


Assuntos
Posicionamento do Paciente/métodos , Doses de Radiação , Proteção Radiológica/métodos , Radiografia Torácica/métodos , Razão Sinal-Ruído , Tomografia Computadorizada por Raios X/métodos , Criança , Humanos , Especificidade de Órgãos , Imagens de Fantasmas , Decúbito Ventral , Radiografia Torácica/instrumentação , Tomografia Computadorizada por Raios X/instrumentação
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