969 research outputs found
The effect of on-line position correction on the dose distribution in focal radiotherapy for bladder cancer
Independent position correction on tumor and lymph nodes; consequences for bladder cancer irradiation with two combined IMRT plans
Abstract Background The application of lipiodol injections as markers around bladder tumors combined with the use of CBCT for image guidance enables daily on-line position correction based on the position of the bladder tumor. However, this might introduce the risk of underdosing the pelvic lymph nodes. In this study several correction strategies were compared. Methods For this study set-up errors and tumor displacements for ten complete treatments were generated; both were based on the data of 10 bladder cancer patients. Besides, two IMRT plans were made for 20 patients, one for the elective field and a boost plan for the tumor. For each patient 10 complete treatments were simulated. For each treatment the dose was calculated without position correction (option 1), correction on bony anatomy (option 2), on tumor only (option 3) and separately on bone for the elective field (option 4). For each method we analyzed the D99% for the tumor, bladder and lymph nodes and the V95% for the small intestines, rectum, healthy part of the bladder and femoral heads. Results CTV coverage was significantly lower with options 1 and 2. With option 3 the tumor coverage was not significantly different from the treatment plan. The ĪD99% (D99%, option n - D99%, treatment plan) for option 4 was small, but significant. For the lymph nodes the results from option 1 differed not significantly from the treatment plan. The median ĪD99% of the other options were small, but significant. ĪD99% for PTVbladder was small for options 1, 2 and 4, but decreased up to -8.5 Gy when option 3 was applied. Option 4 is the only method where the difference with the treatment plan never exceeds 2 Gy. The V95% for the rectum, femoral heads and small intestines was small in the treatment plan and this remained so after applying the correction options, indicating that no additional hot spots occurred. Conclusions Applying independent position correction on bone for the elective field and on tumor for the boost separately gives on average the best target coverage, without introducing additional hot spots in the healthy tissue.</p
Independent position correction on tumor and lymph nodes; consequences for bladder cancer irradiation with two combined IMRT plans
Development of a tool for Individual Aquatic Risk Management among children of 6-12 years (IARM-C).
Background: When it comes to childrenās competence in, on and around water, their risk management also plays an important role. For an optimal and
save participation in aquatic recreation, there is a crucial need to communicate about a realistic perception of potential dangers in relation to oneās own
actual and perceived aquatic skills.
Goals: The aim of this study was to develop and validate a tool for Individual Aquatic Risk Management for Children (IARM-C) useful in both research and
practice regarding water safety for elementary school children and their families, as offered in schools, by local communities and different (water) sport
organisations.
Method: The IARM-C tool was developed and validated in three subsequent phases: (1) a selection of relevant aquatic situations with possible risks for
children based on the literature and discussed with experts, resulting in 10 aquatic situations that were drawn, (2) a pilot study with 22 children to test
content (face) validity, and (3) a cross-sectional study with 70 children (6-12 years, 35 girls and 35 boys, 8.9 Ā± 2.0 years) recruited via convenience sampling
in different (swimming) schools in Brussel (Belgium) to test their risk perception, assessment and decision making in these 10 situations.
Results: For each of the 10 aquatic risk situations of the IARM-C, data collection was organised in a one-on-one interview in order to assist the child in
completing the questionnaire. Six of the 10 pictures resulted in a correct risk perception for > 80% (range between 83-94%) of the children. For one drawn
aquatic risk situation in the swimming pool context (i.e. falling on someone else), only 60% of the children gave a correct description of the situation. In
the drawn open water aquatic risk situations, three pictures scored quite low (range between 49%-54%): warning flag at sea, dangerous objects and
sandbank in the sea.
Conclusions: The IARM-C tool, showing pictures of aquatic risk situations followed by three categories of questions (risk perception, assessment and
decision making), is a useful instrument for further research and education purposes, especially for the swimming pool cases.Desarrollo de una herramienta para la GestiĆ³n individual del riesgo acuĆ”tico entre los niƱos de 6 a 12 aƱos (IARM-C)
Resumen
Antecedentes: Cuando se trata de la competencia de los niƱos en, sobre y alrededor del agua, su competencia de riesgo tambiƩn juega un papel
importante. Para una participaciĆ³n Ć³ptima y segura en la recreaciĆ³n acuĆ”tica, existe una necesidad crucial de comunicar una percepciĆ³n realista de los
peligros potenciales en relaciĆ³n con las propias habilidades acuĆ”ticas reales y percibidas.
Objetivos: El objetivo de este estudio fue desarrollar y validar una herramienta para la GestiĆ³n Individual de Riesgos AcuĆ”ticos para NiƱos (IARM-C) Ćŗtil
tanto en la investigaciĆ³n como en la prĆ”ctica en relaciĆ³n con la seguridad en el agua para los niƱos de la escuela primaria y sus familias, tal y como se
ofrece en las escuelas, por las comunidades locales y diferentes organizaciones deportivas (acuƔticas).
MĆ©todo: La herramienta IARM-C se desarrollĆ³ y validĆ³ en tres fases sucesivos: (1) una selecciĆ³n de situaciones acuĆ”ticas relevantes con posibles riesgos
para los niƱos, basada en la literatura y discutida con expertos, lo que dio como resultado 10 ilustraciones de situaciones acuƔticos, (2) un estudio piloto
con 22 niƱos para comprobar la validez (aparente) del contenido, y (3) un estudio transversal con 70 niƱos (35 niƱas y 35 niƱos, 6-12 aƱos, 8.9 Ā± 2.0 aƱos)
seleccionados mediante muestreo de conveniencia en diferentes escuelas (de nataciĆ³n) de Bruselas (BĆ©lgica) para comprobar su percepciĆ³n de los riesgos,
su evaluaciĆ³n y su toma de decisiones en estas 10 situaciones.
Resultados: Para cada una de las 10 situaciones de riesgo acuĆ”tico del IARM-C, la recogida de datos se organizĆ³ en una entrevista individual para ayudar
al niƱo a rellenar el cuestionario. Seis de los 10 dibujos dieron lugar a una percepciĆ³n de riesgo correcta para mĆ”s del 80% (rango entre 83-94%) de los
niƱos. En una de las situaciones de riesgo acuĆ”tico dibujadas en el contexto de la piscina (es decir, la caĆda sobre otra persona), sĆ³lo el 60% de los niƱos
dio una descripciĆ³n correcta de la situaciĆ³n. En las situaciones de riesgo acuĆ”tico dibujadas en aguas abiertas, tres imĆ”genes obtuvieron una puntuaciĆ³n
bastante baja (entre el 49% y el 54%): bandera de advertencia en el mar, objetos peligrosos y banco de arena en el mar.
Conclusiones: La herramienta IARM-C, que muestra imĆ”genes de situaciones de riesgo acuĆ”tico seguidas de tres categorĆas de preguntas (percepciĆ³n del
riesgo, evaluaciĆ³n y toma de decisiones), es un instrumento Ćŗtil para seguir investigando y educando, especialmente para los casos de piscinas
Dietary n-3 fatty acids increase spleen size and postendotoxin circulating TNF in mice; role of macrophages, macrophage precursors, and colony-stimulating factor-1
Contains fulltext :
4891.pdf (publisher's version ) (Open Access
Macrophages promote the progression of premalignant mammary lesions to invasive cancer.
Breast cancer initiation, progression and metastasis rely on a complex interplay between tumor cells and their surrounding microenvironment. Infiltrating immune cells, including macrophages, promote mammary tumor progression and metastasis; however, less is known about the role of macrophages in early stage lesions. In this study, we utilized a transplantable p53-null model of early progression to characterize the immune cell components of early stage lesions. We show that macrophages are recruited to ductal hyperplasias with a high tumor-forming potential where they are differentiated and polarized toward a tumor-promoting phenotype. These macrophages are a unique subset of macrophages, characterized by pro-inflammatory, anti-inflammatory and immunosuppressive factors. Macrophage ablation studies showed that macrophages are required for both early stage progression and primary tumor formation. These studies suggest that therapeutic targeting of tumor-promoting macrophages may not only be an effective strategy to block tumor progression and metastasis, but may also have critical implications for breast cancer prevention
Flow-Dependent Remodeling of Small Arteries in Mice Deficient for Tissue-Type Transglutaminase
Chronic changes in blood flow induce an adaptation of vascular caliber. Thus, arteries show inward remodeling after a reduction in blood flow. We hypothesized that this remodeling depends on the crosslinking enzyme tissue-type transglutaminase (tTG). Flow-dependent remodeling was studied in wild-type (WT) and tTG-null mice using a surgically imposed change in blood flow in small mesenteric arteries. WT mice showed inward remodeling after 2 days of low blood flow, which was absent in arteries from tTG-null mice. Yet, after continued low blood flow for 7 days, inward remodeling was similar in arteries from WT and tTG-null mice. Studying the alternative pathways of remodeling, we identified a relatively high expression of the plasma transglutaminase factor XIII in arteries of WT and tTG-null mice. In addition, vessels from both WT and tTG-null mice showed the presence of transglutaminase-specific crosslinks. An accumulation of adventitial monocytes/macrophages was found in vessels exposed to low blood flow in tTG-null mice. Because monocytes/macrophages may represent a source of factor XIII, tTG-null mice were treated with liposome-encapsulated clodronate. Elimination of monocytes/macrophages with liposome-encapsulated clodronate reduced both the expression of factor XIII and inward remodeling in tTG-null mice. In conclusion, tTG plays an important role in the inward remodeling of small arteries associated with decreased blood flow. Adventitial monocytes/macrophages are a source of factor XIII in tTG-null mice and contribute to an alternative, delayed mechanism of inward remodeling when tTG is absent
Two-year-olds at elevated risk for ASD can learn novel words from their parents
Education and Child Studie
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