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1.
Clin Transl Radiat Oncol ; 29: 85-92, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34189283

RESUMO

INTRODUCTION: In 2020, the ESTRO course on image-guided radiotherapy and chemotherapy in gynaecological cancer was converted into an online version due to the COVID-19 pandemic. This paper describes the change process and evaluates the impact on participants compared with previous live courses. METHODS AND MATERIALS: The 2019 live course contained 41 h of educational content, comprising 33 h of synchronous activities (lectures, interactive activities, videos) and 8 h of homework (contouring, dose planning). For the online course, the lectures were provided as pre-course material (11 mandatory, 22 optional). Contouring/dose planning homework was unchanged. The synchronous sessions were reconfigured as six 2-hour webinars (total educational content ~38 h).Participant numbers/characteristics, engagement and satisfaction for six live courses and the online course were compared. RESULTS: Participant numbers for the online and live courses were similar (90 vs. mean 96). There were more participants from outside Europe (28% vs. mean 18%) and more non-doctors (47% vs. mean 33%). Proportion of participants responding to the pre-course questionnaire was similar (77% vs. mean 78%) but post-course questionnaire response was lower (62% vs. mean 92%).43% participants viewed ≥75% of mandatory lectures before the webinars. 86% viewed the optional lectures. Submissions of contouring and dose planning homework was higher (contouring 77%-90% vs. 56%-69%, dose planning 74%-89% vs. 29%-57%).96% (47/49) participants rated the online course as Excellent (43%) or Good (53%). Overall satisfaction was similar (4.4 vs. mean 4.6). CONCLUSION: Participant satisfaction and engagement with the online course remained high despite less contact time with faculty.

2.
Artigo em Inglês | MEDLINE | ID: mdl-15177164

RESUMO

An attempt has been made to adopt a different approach to evaluate the effect of a protein's charge on its partitioning behaviour in PEG/salt aqueous two-phase systems (ATPS). This has been done using a computer methodology (DelPhi) that allows the calculation of the electrostatic solvation energy that charged proteins present in a particular media such as aqueous polymer-salt systems. This calculation was done for the protein in each of the phases and a correlation was investigated that related the electrostatic energy difference of the protein in each of the phases and its partition coefficient in ATPS. Such correlation resulted in a statistical model that also included the effect of molecular weight and a shape factor at each particular pH. A global correlation which included the effect of pH was also found. All the correlations were statistically evaluated and gave good results.


Assuntos
Cromatografia Líquida/métodos , Técnica Delphi , Eletricidade Estática
3.
Appl Radiat Isot ; 46(10): 975-9, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7496374

RESUMO

In order to study the interaction between an IgM cold agglutinin and the erythrocyte I antigen, the former antibody was labelled with 125I using the Chloramine-T, IODOGEN and Bolton-Hunter methods. High incorporation and adequate stability of the labelled IgM were obtained with all procedures. However, suitable biological activity was maintained only with the Bolton-Hunter method. Further studies suggest that tyrosine iodination affects antigen recognition by this IgM, whereas iodination of amino groups does not. The reagent thus prepared allowed the determination of the number of I sites per erythrocyte as well as the antibody affinity constant.


Assuntos
Aglutininas/sangue , Anemia Hemolítica Autoimune/imunologia , Autoanticorpos/sangue , Antígenos de Histocompatibilidade Classe I/sangue , Fragmentos Fab das Imunoglobulinas/sangue , Imunoglobulina M/sangue , Adulto , Anemia Hemolítica Autoimune/sangue , Complexo Antígeno-Anticorpo/sangue , Cloraminas , Temperatura Baixa , Eritrócitos/imunologia , Testes de Hemaglutinação , Humanos , Indicadores e Reagentes , Radioisótopos do Iodo , Marcação por Isótopo/métodos , Papaína , Valores de Referência , Compostos de Tosil
4.
Braz J Biol ; 64(2): 211-20, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15462293

RESUMO

Final oocyte maturation (FOM) is a process involving a complex set of genetical, biochemical, and morphological mechanisms. FOM involves the shift of a post-vitellogenic follicle to a pre-ovulated oocyte, which is necessary for fertilization by spermatozoan to occur. This process is regulated by a maturation-inducing steroid (MIS) at the follicular level. In other species of scienids fish the MIS, a hydroxilated derivatives of progestagen 17, 20beta, 21-trihydroxy-4-pregnen-3-one (20beta-S), was identified. Although Micropogonias furnieri is the second fishery resource of Uruguay, basic knowledge about its endocrine process is very scarce. The aim of this work was to investigate what steroids are synthesized in vitro by the oocyte follicle of M. furnieri during the maturation process. Fragments of ovary (1 g) in three stages: post-vitellogenic (PV), maturing (Mtg), and mature (M) were incubated with 1 microg x g(-1) of tritiated progesterone (P) at 30, 60, and 180 min. After extraction with ethanol and dichloromethane, steroid metabolites were purified by TLC and rpHPLC. Two progesterone derivatives with identical chromatographic properties of 20beta-S and 17,20beta-dihydroxy-4-pregnen-3-one (17,20beta-P) were purified. In other Teleost fish these steroids are biologically active as MIS. The 17,20beta-P was clearly detected in Mtg and M stages and confirmed by enzymatic oxidation with enzyme 20beta-HSD. The 20beta-S was strongly detected in all Mtg oocytes. The results do not corroborate 20beta-S as a major hormone synthesized in the ovary in FOM as occurs in other scienid fish. A differential steroid synthesis in the advanced oocyte stages suggests that the 20beta-S is acting as a MIS in M. furnieri.


Assuntos
Cortodoxona/análogos & derivados , Cortodoxona/metabolismo , Peixes/fisiologia , Oócitos/fisiologia , Esteroides/metabolismo , Animais , Cromatografia em Camada Fina , Feminino , Peixes/metabolismo , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Fatores de Tempo
5.
Q J Nucl Med ; 40(2): 170-5, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8909102

RESUMO

A study of 99mTc-adenosine-5'-diphosphate (99mTc-ADP) as a radiopharmaceutical for tumour diagnosis is presented. Two different labelling methods, using SnCl2 in alkaline solution and Zn as reducing agents, were developed. Reduction with Sn(II) alkaline solution was the selected method because a lower concentration of ADP (0.5 mg/mL) could be used and a higher radiochemical yield was achieved. A labelled molecule with a radiochemical purity higher than 95%, in vitro stability of at least 6 hours and an over all negative charge was obtained Biodistribution studies carried out in normal mice and rats revealed rapid urinary excretion and no specific accumulation of activity in any other particular organ. This behaviour was similar to that reported for 99mTc-adenosine-5'-triphosphate (99mTc-ATP). Rapid blood clearance, that could be fitted to a bicompartimental model, was also verified. No evidence of in vivo instability was observed. Studies in mice and rats bearing spontaneous mammary adenocarcinomas were performed and the results were compared to those from the 99mTc-ATP studies. Although the tumour models used were not the same, the incorporation of both labelled compounds was very similar. Radioactivity uptake in the tumour and the tumour-to-blood ratio were not notably high. However, a significant increment was observed in the tumour-to-muscle ratio (1.0 +/- 0.2 at 30 minutes to 2.7 +/- 0.4 at 240 minutes). Whole-body autoradiography enabled tumour visualization. Further investigations, including scintigraphic imaging, must be carried to complete the clinical evaluation of 99mTc-ADP as a tumour seeking agent.


Assuntos
Difosfato de Adenosina/análogos & derivados , Neoplasias Experimentais/diagnóstico por imagem , Compostos de Organotecnécio , Compostos Radiofarmacêuticos , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/metabolismo , Difosfato de Adenosina/sangue , Difosfato de Adenosina/química , Difosfato de Adenosina/farmacocinética , Difosfato de Adenosina/urina , Trifosfato de Adenosina/química , Álcalis/química , Animais , Feminino , Masculino , Neoplasias Mamárias Experimentais/diagnóstico por imagem , Neoplasias Mamárias Experimentais/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Músculo Esquelético/metabolismo , Neoplasias Experimentais/metabolismo , Compostos de Organotecnécio/sangue , Compostos de Organotecnécio/química , Compostos de Organotecnécio/farmacocinética , Compostos de Organotecnécio/urina , Oxirredução , Cintilografia , Compostos Radiofarmacêuticos/sangue , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacocinética , Compostos Radiofarmacêuticos/urina , Ratos , Ratos Wistar , Compostos de Estanho/química , Distribuição Tecidual , Zinco/química
6.
Braz. j. biol ; 64(2): 211-220, May 2004. ilus, tab, graf
Artigo em Inglês | LILACS | ID: lil-365635

RESUMO

A maturação ovocitária final (FOM) é um processo complexo que envolve mecanismos genéticos, bioquímicos e morfológicos que conduzem à transformação de um ovócito pós-vitelogênico em um ovócito apto a ser fertilizado. Esse processo está regulado pelo hormônio esteróide indutor da maturação ovocitária final (MIS), o qual é sintetizado no folículo. Em outras espécies de Sciaenidae, o MIS foi identificado como um derivado hidroxilado da progesterona 17, 20beta, 21-trihydroxy-4-pregnen-3-one (20beta-S). Micropogonias furnieri é um recurso superexplorado na costa uruguaia, contudo, seus processos endócrinos são pouco conhecidos. O objetivo deste trabalho foi pesquisar quais esteróides são sintetizados in vitro pelos folículos em maturação de M. furnieri. Fragmentos de ovários (1 g) foram incubados em três estágios diferentes: pós-vitelogênese (PV), em maturação (Mtg) e maduros (M) com 1 mg/g de progesterona tritriada (P) durante 30, 60 e 180 min. Depois da extração dos esteróides com etanol e diclorometano, esses foram purificados e identificados utilizando-se TLC, rpHPLC e oxidação enzimática. Foram identificados dois derivados de progesterona com idênticas propriedades cromatográficas ao 20beta-S e 17,20beta-dihydroxy-4-pregnen-3-one (17,20beta-P), os quais, em outras espécies de peixes, apresentam atividade biológica como o MIS. A 17,20beta-P foi observada claramente nos estágios Mtg e M e confirmada pela oxidação com a enzima 20beta-HSD. A 20beta-S foi claramente observada nos ovários em maturação (Mtg). Os resultados não permitiram confirmar que 20beta-S é o hormônio mais sintetizado nos estágios estudados, como ocorre em outras espécies de ciaenídeos, mas a presença de uma síntese diferencial no estágio de maturação sugere que 20beta-S esteja atuando como o MIS em M. furnieri.


Assuntos
Animais , Feminino , Peixes , Oócitos , Esteroides , Cromatografia em Camada Fina , Fatores de Tempo
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