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1.
CBE Life Sci Educ ; 22(4): ar51, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37906686

RESUMO

Random call has been proposed as an inclusive and equitable practice that engages students in learning. However, this inclusion may come with a cost. In some contexts, students experience anxiety and distress when being called on. Recently, focus has shifted to critical components of random call that may mitigate this cost. We examined how community college (CC) students perceive being called on by addressing 1) benefits that help their learning and 2) characterizing the anxiety students experience through this practice. To do this, we surveyed students in six biology courses taught by six faculty members over six academic quarters. We analyzed survey responses from 383 unique students (520 total responses) using mixed methods. Qualitative responses were coded and consensus codes revealed that students saw benefits to being called on, including paying attention and coming prepared. Qualitative codes also revealed different types of anxiety, both distress and eustress. Analysis of Likert scale survey data revealed perceptions of increased student interaction with their peers in warm random call classes. Furthermore, warm random call may increase participation in class discussions, and it is not correlated with increased extreme anxiety. These data suggest warm random call used in smaller, community college classes, may contribute to students' positive perceptions of being called on.


Assuntos
Aprendizagem , Estudantes , Humanos , Docentes , Inquéritos e Questionários , Biologia/educação
2.
CBE Life Sci Educ ; 22(2): ar21, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37172050

RESUMO

Undergraduate research experiences have been widely demonstrated as a beneficial and essential component of the college experience. However, many community colleges face barriers and lack of support in implementing such research programs, which means a significant number of community college students miss out on these impactful experiences. Course-based undergraduate research experiences (CUREs) represent a feasible way to increase access to research experiences within community colleges. To investigate whether these CURE opportunities resulted in comparable to 4-year university CURE students, a CURE program was developed across various disciplines in a large community college and the impact on community college students was assessed. Analysis of both qualitative and quantitative data showed that students reported improvement in research skills, increases in confidence, and increases in educational aspirations. Peer interactions and instructor relationships in CUREs were identified as key factors associated with increases in research skills. Key factors associated with increases in educational aspirations included confidence in research-based courses, seeking additional research opportunities, and building a meaningful relationship with the instructor, but only if confidence increased as well. Our findings indicate that CUREs positively impact student outcomes in the community college setting and may provide increased access to research experiences.


Assuntos
Currículo , Estudantes , Humanos , Universidades , Avaliação Educacional
3.
J Med Radiat Sci ; 70 Suppl 2: 99-106, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36502538

RESUMO

The introduction of magnetic resonance (MR) linear accelerators (MR-Linacs) into radiotherapy departments has increased in recent years owing to its unique advantages including the ability to deliver online adaptive radiotherapy. However, most radiation oncology professionals are not accustomed to working with MR technology. The integration of an MR-Linac into routine practice requires many considerations including MR safety, MR image acquisition and optimisation, image interpretation and adaptive radiotherapy strategies. This article provides an overview of training and credentialing requirements for radiation oncology professionals to develop competency and efficiency in delivering treatment safely on an MR-Linac.


Assuntos
Radio-Oncologistas , Radioterapia Guiada por Imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Aceleradores de Partículas , Radioterapia Guiada por Imagem/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Espectroscopia de Ressonância Magnética , Credenciamento
4.
J Med Radiat Sci ; 70 Suppl 2: 94-98, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36572532

RESUMO

The introduction of magnetic resonance (MR) linear accelerators (MR-Linac) marks the beginning of a new era in radiotherapy. MR-Linac systems are currently being operated by teams of radiation therapists (RTs), radiation oncology medical physicists (ROMPs) and radiation oncologists (ROs) due to the diverse and complex tasks required to deliver treatment. This is resource-intensive and logistically challenging. RT-led service delivery at the treatment console is paramount to simplify the process and make the best use of this technology for suitable patients with commonly treated anatomical sites. This article will discuss the experiences of our department in developing and implementing an RT-led workflow on the 1.5 T MR-Linac.


Assuntos
Radioterapia (Especialidade) , Radioterapia Guiada por Imagem , Humanos , Imageamento por Ressonância Magnética , Planejamento da Radioterapia Assistida por Computador , Espectroscopia de Ressonância Magnética
6.
J Med Imaging Radiat Oncol ; 66(1): 138-145, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34643065

RESUMO

INTRODUCTION: The magnetic resonance linear accelerator (MRL) offers improved soft tissue visualization to guide daily adaptive radiotherapy treatment. This manuscript aims to report initial experience using a 1.5 T MRL in the first 6 months of operation, including training, workflows, timings and dosimetric accuracy. METHODS: All staff received training in MRI safety and MRL workflows. Initial sites chosen for treatment were stereotactic and hypofractionated prostate, thoraco-abdomino-pelvic metastasis, prostate bed and bladder. The Adapt To Shape (ATS) workflow was chosen to be the focus of treatment as it is the most robust solution for daily adaptive radiotherapy. A workflow was created addressing patient suitability, simulation, planning, treatment and peer review. Treatment times were recorded breaking down into the various stages of treatment. RESULTS: A total of 37 patients were treated and 317 fractions delivered (of which 313 were delivered using an ATS workflow) in our initial 6 months. Average treatment times over the entire period were 50 and 38 min for stereotactic and non-stereotactic treatments respectively. Average treatment times reduced each month. The average difference between reference planned and ionization chamber measured dose was 0.0 ± 1.4%. CONCLUSION: The MRL was successfully established in an Australian setting. A focus on training and creating a detailed workflow from patient selection, review and treatment are paramount to establishing new treatment programmes.


Assuntos
Planejamento da Radioterapia Assistida por Computador , Radioterapia Guiada por Imagem , Austrália , Humanos , Imageamento por Ressonância Magnética , Masculino , Aceleradores de Partículas , Dosagem Radioterapêutica , Fluxo de Trabalho
7.
Proc Natl Acad Sci U S A ; 111(41): E4323-31, 2014 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-25258416

RESUMO

Germ cells are maintained in a pristine non-aging state as they proliferate over generations. Here, we show that a novel function of the Caenorhabditis elegans RNA interference proteins RNAi spreading defective (RSD)-2 and RSD-6 is to promote germ cell immortality at high temperature. rsd mutants cultured at high temperatures became progressively sterile and displayed loss of small interfering RNAs (siRNAs) that target spermatogenesis genes, simple repeats, and transposons. Desilencing of spermatogenesis genes occurred in late-generation rsd mutants, although defective spermatogenesis was insufficient to explain the majority of sterility. Increased expression of repetitive loci occurred in both germ and somatic cells of late-generation rsd mutant adults, suggesting that desilencing of many heterochromatic segments of the genome contributes to sterility. Nuclear RNAi defective (NRDE)-2 promotes nuclear silencing in response to exogenous double-stranded RNA, and our data imply that RSD-2, RSD-6, and NRDE-2 function in a common transgenerational nuclear silencing pathway that responds to endogenous siRNAs. We propose that RSD-2 and RSD-6 promote germ cell immortality at stressful temperatures by maintaining transgenerational epigenetic inheritance of endogenous siRNA populations that promote genome silencing.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/citologia , Caenorhabditis elegans/metabolismo , Células Germinativas/citologia , Células Germinativas/metabolismo , RNA Interferente Pequeno/metabolismo , Animais , Apoptose , Linhagem Celular Transformada , Proliferação de Células , Segregação de Cromossomos , Regulação da Expressão Gênica , Inativação Gênica , Loci Gênicos , Infertilidade , Mutação , Não Disjunção Genética , Espermatogênese , Estresse Fisiológico , Sequências de Repetição em Tandem/genética , Temperatura , Transcrição Gênica
8.
Aging Cell ; 13(2): 245-53, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24134677

RESUMO

Homeostasis of postmitotic and proliferating cells is maintained by pathways that repress stress. We found that the Caenorhabditis elegans histone 3 lysine 4 (H3K4) demethylases RBR-2 and SPR-5 promoted postmitotic longevity of stress-resistant daf-2 adults, altered pools of methylated H3K4, and promoted silencing of some daf-2 target genes. In addition, RBR-2 and SPR-5 were required for germ cell immortality at a high temperature. Transgenerational proliferative aging was enhanced for spr-5; rbr-2 double mutants, suggesting that these histone demethylases may function sequentially to promote germ cell immortality by targeting distinct H3K4 methyl marks. RBR-2 did not play a comparable role in the maintenance of quiescent germ cells in dauer larvae, implying that it represses stress that occurs as a consequence of germ cell proliferation, rather than stress that accumulates in nondividing cells. We propose that H3K4 demethylase activities promote the maintenance of chromatin states during stressful growth conditions, thereby repressing postmitotic aging of somatic cells as well as proliferative aging of germ cells.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/citologia , Senescência Celular , Histona Desmetilases/metabolismo , Histonas/metabolismo , Lisina/metabolismo , Mitose , Proteína 2 de Ligação ao Retinoblastoma/metabolismo , Animais , Caenorhabditis elegans/enzimologia , Proliferação de Células , Fertilidade , Células Germinativas/citologia , Células Germinativas/metabolismo , Heterozigoto , Longevidade , Metilação , Mutação/genética , Fenótipo , Temperatura
9.
Biochim Biophys Acta ; 1780(3): 486-96, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18269919

RESUMO

Cell adhesion to the extracellular matrix (ECM) via integrin adhesion receptors initiates signaling cascades leading to changes in cell behavior. While integrin clustering is necessary to initiate cell attachment to the matrix, additional membrane components are necessary to mediate the transmembrane signals and the cell adhesion response that alter downstream cell behavior. Many of these signaling components reside in glycosphingolipid-rich and cholesterol-rich membrane domains such as Tetraspanin Enriched Microdomains (TEMs)/Glycosynapse 3 and Detergent-Resistant Microdomains (DRMs), also known as lipid rafts. In the following article, we will review examples of how components in these membrane microdomains modulate integrin adhesion after initial attachment to the ECM. Additionally, we will present data on a novel adhesion-responsive transmembrane glycoprotein Gp140/CUB Domain Containing Protein 1, which clusters in epithelial cell-cell contacts. Gp140 can then be phosphorylated by Src Family Kinases at tyrosine 734 in response to outside-in signals-possibly through interactions involving the extracellular CUB domains. Data presented here suggests that outside-in signals through Gp140 in cell-cell contacts assemble membrane clusters that associate with membrane microdomains to recruit and activate SFKs. Active SFKs then mediate phosphorylation of Gp140, SFK and PKCdelta with Gp140 acting as a transmembrane scaffold for these kinases. We propose that the clustering of Gp140 and signaling components in membrane microdomains in cell-cell contacts contributes to changes in cell behavior.


Assuntos
Antígenos CD/metabolismo , Moléculas de Adesão Celular/metabolismo , Células Epiteliais/metabolismo , Microdomínios da Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Transdução de Sinais , Sequência de Aminoácidos , Anticorpos Monoclonais/farmacologia , Antígenos CD/química , Antígenos CD/imunologia , Antígenos de Neoplasias , Adesão Celular/efeitos dos fármacos , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/imunologia , Comunicação Celular/efeitos dos fármacos , Células Cultivadas , Detergentes/farmacologia , Epiderme/efeitos dos fármacos , Epiderme/patologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/enzimologia , Queratinócitos/patologia , Microdomínios da Membrana/efeitos dos fármacos , Modelos Biológicos , Dados de Sequência Molecular , Proteínas de Neoplasias/química , Proteínas de Neoplasias/imunologia , Fosforilação/efeitos dos fármacos , Estrutura Terciária de Proteína , Transporte Proteico/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , beta-Ciclodextrinas/farmacologia , Quinases da Família src/metabolismo
10.
J Cell Sci ; 118(Pt 15): 3471-85, 2005 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16079289

RESUMO

Quiescent epidermis anchors to laminin 5 in the basement membrane via integrin alpha6beta4. Wounding elevates expression of laminin 5, generating leading keratinocytes (LKs) that migrate via beta1 integrins. Laminin 5 was evaluated as a regulator of cell signaling, and mRNA and protein expression in LKs. An in vitro wound model was developed based on suspension and re-adhesion of quiescent human keratinocytes (HKs). DNA microarrays identified multiple mRNAs elevated 1.5 hours after suspension and re-adhesion including activation transcription factor 3 (ATF3). In vitro and in vivo, levels of ATF3 protein elevate in nuclei of LKs, but not in nuclei of the following cells, 2 hours after suspension or wounding but decline by 12-18 hours post injury. Significantly, null defects in laminin 5 or integrin beta4 that inhibit anchorage chronically elevate ATF3 in vivo. This suggests that adhesion to laminin 5, but not other ligands, suppresses activation. On suspension, ATF3 and other transcripts in the microarrays are elevated by phosphorylated p38 mitogen-activated protein kinase (P-p38), a stress kinase that regulates mRNA and cell motility. Inhibition of P-p38 with SB203580 prevents phosphorylation of ATF2, a transcription factor for ATF3 in LKs. Re-adhesion to laminin 5 via alpha6beta4 dephosphorylates P-p38 and suppresses ATF3 protein relative to cells in suspension. Thus, wounding of quiescent HKs disrupts laminin 5 adhesion to activate p38, generating mRNA transcripts that define LKs. Adhesion to deposits of laminin 5 via alpha6beta4 suppresses P-p38 and activation mRNAs including ATF3. Defects in laminin 5 and alpha6beta4 sustain P-p38 with probable pathological effects on transcription and migration.


Assuntos
Queratinócitos/metabolismo , Pele/lesões , Cicatrização/fisiologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Adesão Celular/fisiologia , Moléculas de Adesão Celular/metabolismo , Movimento Celular/fisiologia , Humanos , Imidazóis/farmacologia , Integrina alfa6beta4/metabolismo , Queratinócitos/química , Queratinócitos/enzimologia , Camundongos , Análise de Sequência com Séries de Oligonucleotídeos , Fosforilação , Piridinas/farmacologia , RNA Mensageiro/química , RNA Mensageiro/metabolismo , Pele/citologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Calinina
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