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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 195: 148-156, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29414572

RESUMO

Fabrication of multifunctional smart vehicles for drug delivery is a fascinating challenge of multidisciplinary research at the crossroads of materials science, physics and biology. We demonstrate a prototypical microcapsule system that is capable of encapsulating hydrophobic molecules and at the same time reveals magnetic properties. The microcapsules are prepared using a templated synthesis approach where the molecules to be encapsulated (Nile Red) are present in the organic droplets that are suspended in the polymerization solution which also contains magnetic nanoparticles. The polymer (polypyrrole) grows on the surface of organic droplets encapsulating the fluorescent dye in the core of the formed microcapsule which incorporates the nanoparticles into its wall. For characterization of the resulting structures a range of complementary physicochemical methodology is used including optical and electron microscopy, magnetometry, 1H NMR and spectroscopy in the visible and X-ray spectral ranges. Moreover, the microcapsules have been examined in biological environment in in vitro and in vivo studies.


Assuntos
Cápsulas/química , Colo/efeitos dos fármacos , Corantes Fluorescentes/química , Magnetismo , Oxazinas/química , Polímeros/química , Sistema Respiratório/efeitos dos fármacos , Animais , Cápsulas/administração & dosagem , Corantes Fluorescentes/administração & dosagem , Humanos , Interações Hidrofóbicas e Hidrofílicas , Masculino , Oxazinas/administração & dosagem , Ratos , Ratos Wistar
2.
Pract Radiat Oncol ; 4(5): 288-293, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25194096

RESUMO

PURPOSE: To characterize nonrespiratory stomach motion in the fasting state and postprandial. METHODS AND MATERIALS: Ten healthy volunteers underwent 2-dimensional Fiesta cine magnetic resonance imaging studies in 30-second voluntary breath hold, in axial, coronal, and 2 oblique planes while fasting, and 5, 15, 30, 45, and 60 minutes postmeal. Each stomach contour was delineated and sampled with 200 points. Matching points were found for all contours in the same 30-second acquisition. Using deformable parametric analysis (Matlab, version 7.1), mean magnitude, and standard deviation of displacement of each point were determined for each patient. Maximal, minimal, and median population values in 6 cardinal, and in any direction, were calculated. RESULTS: The median of mean displacements for the baseline position of each point was small and rarely exceeded 1.1 mm; greatest value was 1.6 mm superior-inferior. Median displacement (pooled across time) in the right-left, superior-inferior, and anterior-posterior directions was 0.3 (range, -0.7 to 1.3), 0.8 (-0.4 to 2.4), and 0.3 (-1.1 to 1.6) mm, respectively. Fasting and postprandial standard deviation did not differ. CONCLUSIONS: Nonrespiratory stomach displacement is small and stomach position is stable after a small, standard meal. Radiation therapy may be delivered at any time within the first hour after eating without significant compromise of planned planning target volumes.


Assuntos
Jejum/fisiologia , Período Pós-Prandial/fisiologia , Estômago/diagnóstico por imagem , Estômago/fisiologia , Adulto , Ingestão de Alimentos/fisiologia , Feminino , Voluntários Saudáveis , Humanos , Imagem Cinética por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Radiografia , Planejamento da Radioterapia Assistida por Computador , Adulto Jovem
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 131: 667-73, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24854245

RESUMO

Pyrene, a fluorescent dye, was incorporated into polystyrene particles coated with polypyrrole. The incorporation was achieved by treating the polypyrrole/polystyrene (PPy/PS) beads in a tetrahydrofuran (THF) solution of the pyrene fluorophore followed by rinsing with methanol. The polystyrene cores of the beads swell in THF, allowing penetration of pyrene molecules into the polystyrene structure. The addition of methanol causes contraction of the swollen polystyrene, which encapsulates the dye molecules inside the beads. It is shown that the polypyrrole coating is permeable with respect to both the dye and the solvent, allowing the transport of molecules between the polystyrene cores and the contacting solution. The polypyrrole adlayer can be used as a matrix for the incorporation of magnetic nanoparticles. Embedded particles provide magnetic functionality to the PPy/PS beads. It is demonstrated that the pyrene-loaded beads can be manipulated with an external magnetic field.


Assuntos
Corantes Fluorescentes/química , Imãs/química , Polímeros/química , Poliestirenos/química , Pirenos/química , Pirróis/química , Corantes Fluorescentes/administração & dosagem , Furanos/química , Fenômenos Magnéticos , Nanopartículas/química , Nanopartículas/ultraestrutura , Pirenos/administração & dosagem
4.
Acta Oncol ; 49(7): 1101-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20831502

RESUMO

PURPOSE: Evaluating a method for anatomic changes assessment and actually delivered doses during head and neck (H&N) cancer radiotherapy (RT) utilizing volumetric images from cone-beam CT (CBCT) and a commercially available deformable image registration (DIR) software. MATERIAL AND METHODS: Thirty-three daily acquired CBCT image sets and the planning CT of one H&N cancer patient were retrospectively transferred from a standard treatment planning system (TPS) to the DIR software. The planning CT was deformed to each CBCT and the contours delineated for planning purposes were propagated. Transfer of each deformed planning CT back into the TPS enabled re-calculation of the actual daily delivered dose distribution based on online image-guidance. For both normal tissues and target volumes the deformed contours were visually evaluated and dose-volume histogram (DVH) parameters were calculated. RESULTS: The workflow of the method took 45 minutes to estimate delivered dose for each treatment fraction. Propagated deformed contours were acceptable for evaluating changes in anatomy. Based on daily DVH parameters the actual delivered dose could be monitored. CONCLUSION: A proof-of-principle method to quantitatively monitor anatomical changes and delivered dose during the course of fractionated RT for H&N cancer has been demonstrated. This provides a tool for exploring adaptive re-planning strategies.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/radioterapia , Tomografia Computadorizada de Feixe Cônico/métodos , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Algoritmos , Carcinoma de Células Escamosas/patologia , Ritmo Circadiano/fisiologia , Cabeça/diagnóstico por imagem , Cabeça/patologia , Cabeça/efeitos da radiação , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Pescoço/diagnóstico por imagem , Pescoço/patologia , Pescoço/efeitos da radiação , Tamanho do Órgão , Órgãos em Risco/patologia , Órgãos em Risco/efeitos da radiação , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Dosagem Radioterapêutica
5.
Int J Radiat Oncol Biol Phys ; 77(1): 53-9, 2010 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19665320

RESUMO

PURPOSE: To quantify the interfraction and breathing organ motion during adjuvant radiotherapy for gastric cancer and assess organ stability in different breathing states. METHODS AND MATERIALS: A planning computed tomography (CT) scan and serial study CT scans in free breathing, voluntary inhale and exhale were performed in weeks 1, 3, and 5 of radiotherapy for 22 resected gastric patients. All data sets were fused to register the vertebral bodies. The regions of interest (kidneys, stomach, liver, pancreas, celiac axis, and porta hepatis) or points of interest (POIs; left dome of diaphragm, splenic hilum) were identified. For each region of interest, a POI was automatically placed at the center of mass. The interfraction displacement and breathing amplitude were assessed in the craniocaudal (CC), anteroposterior (AP), and right-left (RL) directions. RESULTS: Comparison of the serial free-breathing CT scans with the planning CT scan showed a median displacement of all POIs of 5.6, 2.2, and 1.8 mm in the CC, AP, and RL directions, respectively. Comparison of the serial inhale scans with the first inhale scan showed a displacement of 4.9, 2.6, and 1.8 mm in the CC, AP, and RL directions, respectively. The comparable values for the exhale scans were 5.1, 2.0, and 1.8 mm. The displacements of the organs were similar in the free breathing, inhale, and exhale states. The median respiratory amplitude in the CC, AP, and RL direction was 14, 4.8, and 1.7 mm, respectively. CONCLUSION: The median interfraction displacement of the POIs relative to the vertebral bodies was about 6 mm in the CC direction and 2 mm in the other directions. The planning target volume margins need to account for these shifts. Individual assessment of respiratory motion is recommended to identify patients with unusually large respiratory amplitude.


Assuntos
Movimento , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Respiração , Neoplasias Gástricas/diagnóstico por imagem , Artéria Celíaca/diagnóstico por imagem , Diafragma/diagnóstico por imagem , Humanos , Rim/diagnóstico por imagem , Fígado/diagnóstico por imagem , Pâncreas/diagnóstico por imagem , Reprodutibilidade dos Testes , Coluna Vertebral/diagnóstico por imagem , Baço/diagnóstico por imagem , Estômago/diagnóstico por imagem , Neoplasias Gástricas/radioterapia , Tomografia Computadorizada por Raios X/métodos
6.
Hum Mutat ; 21(5): 553-4, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12673801

RESUMO

Sixty high-risk breast and/or ovarian cancer families from North-Eastern Poland were screened for germline mutations in BRCA1 (MIM# 113705) and BRCA2 (MIM# 600185), using a combination of protein truncation test, denaturing high-performance liquid chromatography and direct sequencing. Sixteen (27%) of the families were found to carry nine different BRCA mutations, including 14 families with BRCA1 mutation and two families with BRCA2 mutation. The results suggest the presence of two strong BRCA1 founder mutations in the Polish population - 5382insC (6 families) and 300T>G (Cys61Gly; 3 families). The remaining seven mutations were found in single families and included three previously reported BRCA1 mutations (185delAG, 2682C>T [Gln855Ter] and 3819del5), a novel BRCA1 mutation (IVS14+1G>A), as well as two BRCA2 mutations (4088delA and 7985G>A [Trp2586Ter]) not previously observed in Polish families. We confirm the strong influence of two Central-Eastern European BRCA1 founder mutations in familial breast and/or ovarian cancer in Poland. We also conclude that the Polish population has a more dispersed BRCA mutation spectrum than had been earlier thought. This warrants further careful BRCA mutation screening in order to optimise genetic counselling and disease prevention in affected families.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Neoplasias Ovarianas/genética , Adulto , Idoso , Análise Mutacional de DNA , DNA de Neoplasias/química , DNA de Neoplasias/genética , Saúde da Família , Feminino , Humanos , Pessoa de Meia-Idade , Mutagênese Insercional , Linhagem , Mutação Puntual , Polônia , Deleção de Sequência
8.
Gynecol Oncol ; 85(2): 381-3, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11972405

RESUMO

BACKGROUND: To preserve fertility, hemi-pelvis irradiation was chosen for locoregional groin recurrence of vulvar cancer in an adolescent. CASE: A case of squamous cell vulvar carcinoma in uncommonly young patient is presented. First surgical management (local excision of T1N0M0 tumor of the right labia minora) was performed at the age of 16.5 years. Further therapy included wide local resection of recurrent local lesion, two subsequent ipsilateral groin dissections of nodal metastases (with extranodal spread at the first instance), and ipsilateral pelvic lymphadenectomy. The patient was administered external beam irradiation of 45 Gy to the hemi-pelvis followed by 10.8 Gy boost to the right inguinal region. After 6.5 years from the completion of radiotherapy the patient is free of disease. She managed to conceive but the labor was premature and the infant died in its 7th week of life. CONCLUSION: In this case salvage hemi-pelvic irradiation for groin metastases of vulvar cancer has proved to be an effective treatment, allowing preservation of hormonal and obstetric functions. Partial post-irradiation damage of the uterus might have caused premature labor. Thus, special obstetric care is advisable in such situations.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Fertilidade , Recidiva Local de Neoplasia/radioterapia , Neoplasias Vulvares/radioterapia , Adulto , Feminino , Humanos , Terapia de Salvação
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