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1.
Rev Med Chil ; 148(10): 1461-1466, 2020 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-33844716

RESUMO

BACKGROUND: The suspension of face-to-face teaching activity due to the COVID-19 pandemic forced an abrupt transition to distance learning in Spanish universities. AIM: To know how medical students value distance learning in the context of COVID-19 pandemic. MATERIAL AND METHODS: Undergraduate medical students from first to fifth year in Barcelona (Spain) were invited to answer an anonymous online survey about their perceptions and level of satisfaction with virtual learning. RESULTS: Of 483 students invited to the survey, 244 (50.5%) answered it. Respondents from the first and second year rated distance learning as acceptable (mean 3.1) on a Likert scale from 1 to 5. Those from third to fifth years rated distance learning as unsatisfactory (mean 2.7). The best evaluated aspects were synchronous lectures (3.9) and lectures based on cases (3.4). The worst evaluated issues were motivation (2.3), interaction with faculty (2.1), and additional workload (0.7). CONCLUSIONS: The perceptions expressed by these students reinforce the importance of facilitating communication, motivation and participation of students in distance learning in Medicine.


Assuntos
COVID-19 , Educação a Distância , Medicina , Estudantes de Medicina , Humanos , Pandemias , Percepção , SARS-CoV-2 , Espanha
2.
Mol Carcinog ; 55(5): 411-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25647613

RESUMO

Oxaliplatin-resistant LoVo colon cancer cells overexpressing c-MET and VEGFR-1 were selected to study several signaling pathways involved in chemoresistance, as well as the effect of increasing amounts of VEGF in the regulation of c-MET. In comparison with chemosensitive LoVo colon cancer cells, oxaliplatin-resistant cells (LoVoR) overexpress and phosphorylate c-MET, upregulate the expression of transmembrane and soluble VEGFR-1 and, unexpectedly, downregulate VEGF. In addition, LoVoR cells activate other transduction pathways involved in chemoresistance such as Akt, ß-catenin-TCF4 and E-cadherin. While c-MET is phosphorylated in LoVoR cells expressing low levels of VEGF, c-MET phosphorylation decreases when recombinant VEGF is added into the culture medium. Inhibition of c-MET by VEGF is mediated by VEGFR-1, since phosphorylation of c-MET in the presence of VEGF is restored after silencing VEGFR-1. Dephosphorylation of c-MET by VEGF suggests that tumors coexpressing VEGFR-1 and c-MET may activate c-MET as a result of anti-VEGF therapy.


Assuntos
Antineoplásicos/farmacologia , Neoplasias do Colo/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Compostos Organoplatínicos/farmacologia , Proteínas Proto-Oncogênicas c-met/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Células HT29 , Humanos , Oxaliplatina , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-met/genética , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/farmacologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética
3.
J Cell Biochem ; 115(1): 52-61, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23904188

RESUMO

We have previously reported that the major isoform of Flt1/VEGFR-1 expressed in MDA-MB-231 breast cancer cells was a truncated intracellular isoform transcribed from intron 21 (i21 Flt1). This isoform upregulated the active form of Src and increased breast cancer cell invasiveness. Since expression of the transmembrane and soluble Flt1 isoforms of HUVEC is activated by Notch signaling, we wondered whether the expression of the intracellular isoform i21 Flt1 was also dependent on Notch activation. We report here that the expression of i21 Flt1 in HUVEC and MDA-MB-231 cells is downregulated by the γ-secretase inhibitor DAPT. In addition, treatment of MDA-MB-231 cells with siRNA specific for Notch-1 and Notch-3 downregulates the expression of i21 Flt1. In agreement with these findings, HUVEC and MDA-MB-231 breast cancer cells, cultured on dishes coated with recombinant human Dll4 extracellular domain, express higher levels of i21 Flt1. In cancer cells, Flt1 is a target of the micro RNA family miR-200. In MDA-MB-231 breast cancer cells, the truncated intracellular isoform i21 Flt1 is also negatively regulated by miR-200c. Retinoic acid interferes i21 Flt1 expression by downregulating Notch-3 and upregulating miR-200 expression. Treatment of MDA-MB-231 breast cancer cells with both a γ-secretase inhibitor and retinoic acid suppresses the expression of i21 Flt1, providing a new mechanism to explain the effectiveness of this therapeutic approach.


Assuntos
Neoplasias da Mama/genética , Receptores Notch/metabolismo , Tretinoína/farmacologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Proteínas Adaptadoras de Transdução de Sinal , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proteínas de Ligação ao Cálcio , Linhagem Celular Tumoral , Dipeptídeos/farmacologia , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , MicroRNAs/genética , Isoformas de Proteínas , Receptor Notch1/genética , Receptor Notch1/metabolismo , Receptor Notch3 , Receptores Notch/genética , Tretinoína/metabolismo , Regulação para Cima/efeitos dos fármacos , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo
4.
Int J Med Educ ; 13: 148-153, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35716402

RESUMO

Objectives: To compare the communication skills shown by medical students during simulated patient interviews between those who received training in communication during the preclinical years and those who did not. Methods: A retrospective study was conducted to analyze the communication skills of several cohorts of fourth-year medical students from Universitat Internacional de Catalunya during simulated patient interviews. Out of a total of 477 students included in the study, 229 (48%) had received training in communication skills through a 60-hour elective course during the preclinical second year, while the remaining 248 (52%) had received none. Communication skills were assessed by an evaluation team using a numerical scale (0 to 10) that included eight categories: "verbal", "non-verbal", "empathy", "concreteness", "warmth", "message content", "assertiveness", and "respect". Scores obtained by trained and non-trained students were compared using the t-test. Results: A trend towards obtaining better results was observed among students who had received communication training (mean score: 6.98/10) versus none (6.83/10, t(1,869)=-1.95, p=0.05). Non-trained male students obtained significantly lower mean scores than non-trained females in the categories of "respect" (7.48/10 vs. 7.83/10, t(968)=-2.89, p<0.01), "verbal communication" (6.87/10 vs. 7.15/10, t(968)=-2.61, p=0.01), "warmth" (6.53/10 vs. 6.95/10, t(968)=-3.40, p<0.01), and "non-verbal communication" (6.49/10 vs. 6.79/10, t(968)=-2.48, p=0.01). Trained female and male students had similar scores. Conclusions: Training in communication skills during the preclinical years may improve fourth-year students' performance in simulated interviews with patients, particularly among males. These results demonstrate the importance of introducing specific training in communication skills early in the undergraduate medical curriculum.


Assuntos
Educação de Graduação em Medicina , Estudantes de Medicina , Competência Clínica , Comunicação , Currículo , Educação de Graduação em Medicina/métodos , Feminino , Humanos , Masculino , Relações Médico-Paciente , Estudos Retrospectivos
5.
Med Sci Educ ; 32(2): 337-347, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35223143

RESUMO

Introduction: The first wave of the COVID-19 pandemic resulted in a decreed confinement in Spain from March until the end of term in June 2020, forcing an abrupt transition to exclusive distance learning in universities. We aimed to describe and analyze the perceptions and experiences of undergraduate medical students and faculty members as a consequence of this educational shift so as to identify the key elements for successful online medical learning. Methods: A convergent mixed methods design was employed, using both quantitative and qualitative data collected successively through Phase 1: Online teaching follow-up program; Phase 2: Discussion groups (two focus groups and a nominal group with students and faculty, respectively) and a survey of students from first to fifth year; and Phase 3: Triangulation of qualitative and quantitative data. Results: Thirteen strongly interconnected categories were identified. Four of them played an organizational role: course planning, coordination, communication, and pedagogical coherence. The remaining nine categories were learning outcomes, teaching methodology, online resources, evaluation, time management, workload, student motivation, participation, and teacher-student relationship. Among the key aspects of learning were those that promoted rapport between faculty and students, such as synchronous sessions, especially those based on clinical cases. Conclusions: Promoting student motivation and participation at all levels were the main lessons learned for enhancing online learning and teaching experiences in undergraduate medical education. Key elements to reach this goal are, among others, planning, coordination, communication, and pedagogical coherence. Supplementary Information: The online version contains supplementary material available at 10.1007/s40670-022-01518-9.

7.
Sci Rep ; 8(1): 7047, 2018 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-29728589

RESUMO

All-trans-retinoic acid (RA), the active metabolite of vitamin A, can reduce the malignant phenotype in some types of cancer and paradoxically also can promote cancer growth and invasion in others. For instance, it has been reported that RA induces tumor suppression in tumor xenografts of MDA-MB-468 breast cancer cells while increasing tumor growth and metastases in xenografts of MDA-MB-231 breast cancer cells. The signaling pathways involved in the pro-invasive action of retinoic acid remain mostly unknown. We show here that RA activates the pro-invasive axis Src-YAP-Interleukin 6 (Src-YAP-IL6) in triple negative MDA-MB-231 breast cancer cells, yielding to increased invasion of these cells. On the contrary, RA inhibits the Src-YAP-IL6 axis of triple-negative MDA-MB-468 cells, which results in decreased invasion phenotype. In both types of cells, inhibition of the Src-YAP-IL6 axis by the Src inhibitor PP2 drastically reduces migration and invasion. Src inhibition also downregulates the expression of a pro-invasive isoform of VEGFR1 in MDA-MB-231 breast cancer cells. Furthermore, interference of YAP nuclear translocation using the statin cerivastatin reverses the upregulation of Interleukin 6 (IL-6) and the pro-invasive effect of RA on MDA-MB-231 breast cancer cells and also decreases invasion and viability of MDA-MB-468 breast cancer cells. These results altogether suggest that RA induces pro-invasive or anti-invasive actions in two triple-negative breast cancer cell lines due to its ability to activate or inhibit the Src-YAP-IL6 axis in different cancer cells. The pro-invasive effect of RA can be reversed by the statin cerivastatin.


Assuntos
Interleucina-6/metabolismo , Proteínas Nucleares/metabolismo , Piridinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Tretinoína/farmacologia , Neoplasias de Mama Triplo Negativas/metabolismo , Quinases da Família src/metabolismo , Biomarcadores , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Fosforilação
8.
Sci Rep ; 8(1): 11797, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-30087414

RESUMO

Colorectal cancer (CRC) is one of the most common cancers worldwide, with 8-10% of these tumours presenting a BRAF (V600E) mutation. Cyclins are known oncogenes deregulated in many cancers, but the role of the new subfamily of atypical cyclins remains elusive. Here we have performed a systematic analysis of the protein expression levels of eight atypical cyclins in human CRC tumours and several cell lines, and found that CNTD2 is significantly upregulated in CRC tissue compared to the adjacent normal one. CNTD2 overexpression in CRC cell lines increases their proliferation capacity and migration, as well as spheroid formation capacity and anchorage-independent growth. Moreover, CNTD2 increases tumour growth in vivo on xenograft models of CRC with wild-type BRAF. Accordingly, CNTD2 downregulation significantly diminished the proliferation of wild-type BRAF CRC cells, suggesting that CNTD2 may represent a new prognostic factor and a promising drug target in the management of CRC.


Assuntos
Movimento Celular , Proliferação de Células , Neoplasias do Colo/metabolismo , Ciclinas/metabolismo , Mutação de Sentido Incorreto , Proteínas Proto-Oncogênicas B-raf/metabolismo , Substituição de Aminoácidos , Animais , Linhagem Celular Tumoral , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Ciclinas/genética , Feminino , Humanos , Masculino , Camundongos , Camundongos Nus , Proteínas Proto-Oncogênicas B-raf/genética
9.
Oncogene ; 24(5): 889-901, 2005 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-15580293

RESUMO

Deregulated c-myc gene expression is associated with many human and animal cancers. Myc overexpression promotes the growth of blood and lymphatic vessels, which is due in part to induction of growth factors including vascular endothelial growth factor (VEGF). We determined that the P493-6 human B-cell line increases VEGF production 10-fold upon Myc overexpression. Myc overexpression in avian B cells similarly resulted in high level VEGF production. Real-time RT-PCR analyses showed that Myc did not alter the VEGF mRNA content of these cell lines, indicating that a post-transcriptional mechanism regulates VEGF production. VEGF mRNA translation was examined by RT-PCR analysis of monosome and polysome sucrose gradient fractions from Myc-on and Myc-off P493-6 cells. Myc increased VEGF mRNA translation initiation, as VEGF mRNA loading onto polysomes increased 14-fold in Myc-on cells, and the number of ribosomes loaded per VEGF mRNA increased threefold. This translational regulation is specific to VEGF mRNA, as total polysomes show the same sucrose gradient profile in Myc-on and Myc-off cells, with no change in the percent ribosomes in polysomes, or in the number of ribosomes per polysomal mRNA. Myc stimulates VEGF production by a rapamycin- and LY294002-sensitive pathway, which does not involve alteration of eIF4E activity.


Assuntos
Linfócitos B/fisiologia , Proteínas Proto-Oncogênicas c-myc/genética , RNA Mensageiro/genética , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Sequência de Bases , Linhagem Celular , Primers do DNA , Genes myc , Humanos , Biossíntese de Proteínas , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Rev. méd. Chile ; 148(10)oct. 2020.
Artigo em Espanhol | LILACS | ID: biblio-1389226

RESUMO

Background: The suspension of face-to-face teaching activity due to the COVID-19 pandemic forced an abrupt transition to distance learning in Spanish universities. Aim: To know how medical students value distance learning in the context of COVID-19 pandemic. Material and Methods: Undergraduate medical students from first to fifth year in Barcelona (Spain) were invited to answer an anonymous online survey about their perceptions and level of satisfaction with virtual learning. Results: Of 483 students invited to the survey, 244 (50.5%) answered it. Respondents from the first and second year rated distance learning as acceptable (mean 3.1) on a Likert scale from 1 to 5. Those from third to fifth years rated distance learning as unsatisfactory (mean 2.7). The best evaluated aspects were synchronous lectures (3.9) and lectures based on cases (3.4). The worst evaluated issues were motivation (2.3), interaction with faculty (2.1), and additional workload (0.7). Conclusions: The perceptions expressed by these students reinforce the importance of facilitating communication, motivation and participation of students in distance learning in Medicine.


Assuntos
Humanos , Estudantes de Medicina , Educação a Distância , COVID-19 , Medicina , Percepção , Espanha , Pandemias , SARS-CoV-2
11.
Cells ; 3(1): 92-111, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24709904

RESUMO

One of the best examples of the renaissance of Src as an open door to cancer has been the demonstration that just five min of Src activation is sufficient for transformation and also for induction and maintenance of cancer stem cells [1]. Many tyrosine kinase receptors, through the binding of their ligands, become the keys that unlock the structure of Src and activate its oncogenic transduction pathways. Furthermore, intracellular isoforms of these receptors, devoid of any tyrosine kinase activity, still retain the ability to unlock Src. This has been shown with a truncated isoform of KIT (tr-KIT) and a truncated isoform of VEGFR-1 (i21-VEGFR-1), which are intracellular and require no ligand binding, but are nonetheless able to activate Src and induce cell migration and invasion of cancer cells. Expression of the i21-VEGFR-1 is upregulated by the Notch signaling pathway and repressed by miR-200c and retinoic acid in breast cancer cells. Both Notch inhibitors and retinoic acid have been proposed as potential therapies for invasive breast cancer.

12.
Behav Brain Res ; 256: 291-7, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23973755

RESUMO

Carnitine palmitoyltransferase 1c (CPT1C), a brain-specific protein localized in the endoplasmic reticulum of neurons, is expressed in almost all brain regions, but its only known functions to date are involved in the hypothalamic control of energy homeostasis and in hippocampus-dependent spatial learning. To identify other physiological and behavioral functions of this protein, we performed a battery of neurological tests on Cpt1c-deficient mice. The animals showed intact autonomic and sensory systems, but some motor disturbances were observed. A more detailed study of motor function revealed impaired coordination and gait, severe muscle weakness, and reduced daily locomotor activity. Analysis of motor function in these mice at ages of 6-24 weeks showed that motor disorders were already present in young animals and that impairment increased progressively with age. Analysis of CPT1C expression in different motor brain areas during development revealed that CPT1C levels were low from birth to postnatal day 10 and then rapidly increased peaking at postnatal day 21, which suggests that CPT1C plays a relevant role in motor function during and after weaning. As CPT1C is known to regulate ceramide levels, we measured these biolipids in different motor areas in adult mice. Cerebellar, striatum, and motor cortex extracts from Cpt1c knockout mice showed reduced levels of ceramide and its derivative sphingosine when compared to wild-type animals. Our results indicate that altered ceramide metabolism in motor brain areas induced by Cpt1c deficiency causes progressive motor dysfunction from a young age.


Assuntos
Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiopatologia , Carnitina O-Palmitoiltransferase/deficiência , Transtornos dos Movimentos/fisiopatologia , Animais , Animais Recém-Nascidos , Western Blotting , Carnitina O-Palmitoiltransferase/genética , Carnitina O-Palmitoiltransferase/metabolismo , Ceramidas/metabolismo , Progressão da Doença , Marcha/fisiologia , Masculino , Camundongos Knockout , Atividade Motora/fisiologia , Debilidade Muscular/fisiopatologia , Exame Neurológico , Reflexo/fisiologia , Teste de Desempenho do Rota-Rod , Esfingosina/metabolismo
13.
Mol Ther ; 14(2): 212-7, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16631413

RESUMO

The optimal stem cell source for stem cell gene therapy has yet to be determined. Most large-animal studies have utilized peripheral blood or marrow-derived cells collected after administration of granulocyte colony-stimulating factor (G-SCF) and stem cell factor (SCF); however, SCF is unavailable for clinical use in the United States and the European Union. A recent study in a competitive repopulation assay in the rhesus macaque showed very inefficient marking of G-CSF-mobilized (G/only) peripheral blood (G-PBSC) CD34(+) cells relative to G-CSF and SCF-mobilized cells using vectors with an amphotropic pseudotype. Because G-PBSC would be the preferred target cell population for most clinical stem cell gene therapy applications, we asked whether we could achieve efficient transduction and engraftment of G-PBSC using Phoenix-GALV-pseudotyped vectors. We transplanted three baboons with G/only mobilized CD34(+) cells transduced with GALV-pseudotyped retroviral vectors. We observed high-level, persistent engraftment of gene-modified G-PBSC in all animals with gene marking levels in granulocytes up to 60%. We analyzed amphotropic (PIT2) and GALV (PIT1) receptor expression in G/only cells and found preferential expression of PIT1 after G/only, which may explain the inferior results with amphotropic pseudotypes. These findings demonstrate that high stem cell gene transfer levels can be achieved using G-CSF-mobilized PBSC with Phoenix-GALV-pseudotyped vectors.


Assuntos
Fator Estimulador de Colônias de Granulócitos/farmacologia , Mobilização de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Hematopoéticas , Vírus da Leucemia do Macaco Gibão/genética , Transdução Genética , Animais , Antígenos CD34/análise , Citometria de Fluxo , Técnicas de Transferência de Genes , Hematopoese , Humanos , Papio , Proteínas Recombinantes , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/análise
14.
Am J Pathol ; 163(6): 2233-45, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14633598

RESUMO

Expression of the c-myc proto-oncogene is deregulated in many human cancers. We examined the role of c-Myc in stimulating angiogenesis and lymphangiogenesis in a highly metastatic murine model of Burkitt's lymphoma (E micro -c-myc), where c-Myc is expressed exclusively in B lymphocytes. Immunohistochemical analysis of bone marrow and lymph nodes from young (preneoplastic) E micro -c-myc transgenic mice revealed increased growth of blood vessels, which are functional by dye flow assay. Lymphatic sinuses also increased in size and number within the lymph nodes, as demonstrated by immunostaining for with a lymphatic endothelial marker 10.1.1. The 10.1.1 antibody recognizes VEGFR-2- and VEGFR-3-positive lymphatic sinuses and vessels within lymph nodes, and also recognizes lymphatic vessels in other tissues. Subcutaneously injected dye traveled more efficiently through draining lymph nodes in E micro -c-myc mice, indicating that these hypertrophic lymphatic sinuses increase lymph flow. Purified B lymphocytes and lymphoid tissues from E micro -c-myc mice expressed increased levels of vascular endothelial growth factor (VEGF) by immunohistochemical or immunoblot assays, which could promote blood and lymphatic vessel growth through interaction with VEGFR-2, which is expressed on the endothelium of both vessel types. These results indicate that constitutive c-Myc expression stimulates angiogenesis and lymphangiogenesis, which may promote the rapid growth and metastasis of c-Myc-expressing cancer cells, respectively.


Assuntos
Linfócitos B/metabolismo , Linfoma de Burkitt/fisiopatologia , Linfonodos/irrigação sanguínea , Linfangiogênese , Neovascularização Patológica/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Animais , Circulação Sanguínea , Medula Óssea/irrigação sanguínea , Linfoma de Burkitt/complicações , Linfoma de Burkitt/patologia , Corantes , Linfonodos/patologia , Camundongos , Camundongos Transgênicos , Neovascularização Patológica/etiologia , Neovascularização Patológica/patologia , Proto-Oncogene Mas , Fator A de Crescimento do Endotélio Vascular/metabolismo
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