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2.
Cancer Sci ; 101(3): 826-30, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20132222

RESUMO

(Cancer Sci 2010; 101: 826-830) The purpose was to ascertain whether the recurrence risk patterns for patients with estrogen receptor (ER)-positive (P) and ER-negative (N) breast cancer support the ER-related clinical divergence suggested by the observed different mortality patterns and gene expression profiles. Both recurrence and death were considered in a series of 771 patients undergoing mastectomy. ER status was available for 539 patients. The hazard rates for recurrence and mortality throughout 15 years of follow-up were assessed. The recurrence dynamics displays a bimodal pattern for both ERP and ERN tumors with comparable peak timings. The two curves cross during the 3rd year. By contrast, the mortality dynamics are definitely different for ERP and ERN tumors: during the early follow-up period ERN patients have their highest mortality risk, while ERP patients have their lowest mortality risk. The two curves cross during the 5th year. In spite of the different mortality dynamics, the recurrence dynamics do not demonstrate a major distinction in timing between ERP and ERN breast cancers, suggesting that the metastasis development process following mastectomy is apparently similar for both ER categories. The observed differences in the mortality risk are plausibly attributable to ER-related factors influencing the clinical course from recurrence to death. These clinical findings apparently contradict the occurrence of two different types of breast cancer, notwithstanding the distinct epidemiological, clinical, and molecular features linked to ERP and ERN tumors, although ER levels may concur to establish the event risk levels.


Assuntos
Neoplasias da Mama/cirurgia , Mastectomia , Recidiva Local de Neoplasia/química , Receptores de Estrogênio/análise , Adulto , Idoso , Neoplasias da Mama/química , Neoplasias da Mama/mortalidade , Feminino , Humanos , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Med Teach ; 32(1): e5-11, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20095767

RESUMO

BACKGROUND: During problem-based learning (PBL), students brainstorm on a problem, generate hypotheses and formulate learning objectives. Certain verbal and non-verbal expressions are used by students in response to specific learning issues. AIMS: This study examines the use of these expressions as indices of the learning taking place and the tutors' threshold to intervene. METHODS: Common verbal expressions used by students during PBL were identified and scored on a Likert scale to indicate the learning taking place. These expressions were categorised into the following groups of learning interactions: exploratory questioning, cumulative reasoning and handling conflicts relating to learning. The tutor's threshold for intervention was also scored on a Likert scale. Means for each learning interaction and observed non-verbal expressions were used to construct bar charts for comparison. RESULTS: When the learning interactions involve exploratory questioning or cumulative reasoning, students tend to score high on learning and tutors have high threshold for intervention. When the learning interactions involve handling conflicts relating to knowledge, students score high on learning, but teachers have a low threshold for intervention. CONCLUSION: Verbal and non-verbal expressions from students during PBL are useful indices of learning and can be used to help tutors decide when and when not to intervene.


Assuntos
Educação de Graduação em Medicina , Avaliação Educacional/métodos , Comunicação não Verbal , Grupo Associado , Aprendizagem Baseada em Problemas , Fala , Estudantes de Medicina , Ensino/métodos , Humanos
4.
BMC Cancer ; 9: 7, 2009 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-19133151

RESUMO

BACKGROUND: Women with Down syndrome very rarely develop breast cancer even though they now live to an age when it normally occurs. This may be related to the fact that Down syndrome persons have an additional copy of chromosome 21 where the gene that codes for the antiangiogenic protein Endostatin is located. Can this information lead to a primary antiangiogenic therapy for early stage breast cancer that indefinitely prolongs remission? A key question that arises is when is the initial angiogenic switch thrown in micrometastases? We have conjectured that avascular micrometastases are dormant and relatively stable if undisturbed but that for some patients angiogenesis is precipitated by surgery. We also proposed that angiogenesis of micrometastases very rarely occurs before surgical removal of the primary tumor. If that is so, it seems possible that we could suggest a primary antiangiogenic therapy but the problem then arises that starting a therapy before surgery would interfere with wound healing. RESULTS: The therapy must be initiated at least one day prior to surgical removal of the primary tumor and kept at a Down syndrome level perhaps indefinitely. That means the drug must have virtually no toxicity and not interfere meaningfully with wound healing. This specifically excludes drugs that significantly inhibit the VEGF pathway since that is important for wound healing and because these agents have some toxicity. Endostatin is apparently non-toxic and does not significantly interfere with wound healing since Down syndrome patients have no abnormal wound healing problems. CONCLUSION: We propose a therapy for early stage breast cancer consisting of Endostatin at or above Down syndrome levels starting at least one day before surgery and continuing at that level. This should prevent micrometastatic angiogenesis resulting from surgery or at any time later. Adjuvant chemotherapy or hormone therapy should not be necessary. This can be continued indefinitely since there is no acquired resistance that develops, as happens in most cancer therapies.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Simulação por Computador , Endostatinas/administração & dosagem , Neovascularização Patológica/prevenção & controle , Pré-Medicação , Neoplasias da Mama/genética , Neoplasias da Mama/cirurgia , Síndrome de Down/genética , Endostatinas/genética , Feminino , Humanos , Modelos Biológicos , Neovascularização Patológica/genética , Cicatrização/efeitos dos fármacos
5.
Med Teach ; 30(8): 812-4, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18946825

RESUMO

OBJECTIVE: The study aimed to determine student views of peer feedback on their student-selected study (SSS) module. METHODS: A questionnaire was developed to study perceptions of three groups of medical students (N = 42) towards feedback received from peers about their anatomy SSS presentation. RESULTS: Most students felt comfortable receiving and giving feedback. They also felt that received feedback was fair, adequate and helpful, and that receiving feedback made them reflect. Slightly more students reported inadequate feedback from their peers about the presentations' content, compared to other aspects, due to their peers' relative lack of knowledge about their 'specialized' subject. Students would be reluctant to give feedback if anonymity was removed. CONCLUSION: The attitudes of medical students towards peer feedback were largely positive. We advocate further studies to evaluate quality of feedback, and the role of anonymity in peer feedback, and its effect on group dynamics and cohesion.


Assuntos
Anatomia/educação , Retroalimentação , Grupo Associado , Estudantes de Medicina/psicologia , Currículo , Educação de Graduação em Medicina/métodos , Humanos , Inquéritos e Questionários
6.
Clin Med Oncol ; 2: 347-51, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-21892296

RESUMO

BACKGROUND: Some studies have suggested that breast cancer in black women is more aggressive than in white women. This study's aim was to look for evidence of differences in tumour biology between the two cohorts. METHODS: This study compared the stage, grade and pathological expression of five immunohistochemical markers (oestrogen receptor [ER], progesterone receptor [PR], ERBB2, P53 and cyclin D1 [CCND1]) in tumour biopsies from age-matched cohorts of patients from Nigeria and England. Sixty-eight suitable samples from Nigerian (n = 34) and British (n = 34) breast cancer patients were retrieved from histology tissue banks. RESULTS: There were significant differences between the two cohorts in the expression of ER and CCND1; and stark differences in the clinical stage at presentation. But no significant differences were observed for tumour grade. CONCLUSION: There was a significantly, low ER expression in the Nigerian cases which also predicts a poor response to hormonal therapy as well as a poorer prognosis. Differences in clinical stage at presentation will most likely influence prognosis between Nigerian and British women with breast cancer.

7.
Med Teach ; 29(9): 887-92, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18158659

RESUMO

INTRODUCTION: When medical education became established in Africa, many curricula were adopted from the West so as to achieve comparable standards in training. Over the last half a century however, major global pedagogical shifts have occurred in medical education without African keeping pace. METHODS: This article reviews key pedagogical changes and other innovations in medical education that have occurred over the last half a century as reported in the literature and identifies some of the issues that need to be addressed in Africa. DISCUSSION AND CONCLUSION: Socioeconomic and political instability, failure to rapidly overcome the inertia for change by substituting the old curriculum with a more problem, system and student-based one and redefining the goals of medical education are some of the issues of concern for Africa, and its ability to keep up in the dynamic world of medical education. There are only few faculty and school managers with effective medical education backgrounds to initiate, evaluate and sustain these changes. African medical academics, national governments and the international community need to come together to assist Africa to rise up to these challenges to ensure attainment and sustenance of global standards in medical training.


Assuntos
Educação Médica/tendências , Saúde Global , Internacionalidade , África , Comparação Transcultural , Educação Médica/normas , Emigração e Imigração/tendências , Humanos , Política , Pobreza , Mudança Social , Guerra
8.
Int J Surg ; 5(5): 300-4, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17933694

RESUMO

There is excess breast cancer mortality for African-Americans (AA) compared to European-Americans (EA) of 1.5-2.2 fold that first appeared in 1970s and has been worsening since. This disparity may not be explained solely by reduced access to medical care. We proposed that surgery to remove a primary tumor induces angiogenesis of distant dormant micrometastases in 20% of premenopausal node-positive patients. This hypothesis helps explain the reduced benefit of mammography for women aged 40-49. Interestingly, for AA the average age at diagnosis is 46 while for EA it is 57. The resultant increased proportion of AA premenopausal breast cancer suggests a possible explanation for the AA/EA excess mortality. Early detection, which began in the 1970s, is more effective in postmenopausal women than in premenopausal women. Since AA breast cancer is mostly premenopausal and EA breast cancer is mostly postmenopausal, it might be anticipated that starting in the 1970s because of surgery-induced early mortality, outcome would be superior for EA compared to AA.


Assuntos
Neoplasias da Mama/etnologia , Neoplasias da Mama/fisiopatologia , Mama/patologia , Neovascularização Patológica/etnologia , Neovascularização Patológica/fisiopatologia , Adulto , Negro ou Afro-Americano , Biópsia/efeitos adversos , Mama/cirurgia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Neovascularização Patológica/etiologia , Pós-Menopausa , Pré-Menopausa , População Branca
9.
Cancer ; 110(9): 1880-8, 2007 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17876835

RESUMO

Since the 1970s, overall age-adjusted breast cancer mortality rates in the U.S. have been higher among African American (AA) women than among Caucasian American (CA) women. The racial disparity is not fully explainable based on socioeconomic factors. Suspected biologic factors underlying this trend may be interpreted by both epidemiologic and clinical perspectives. Descriptive epidemiologic studies suggest that breast cancer may be a mixture of at least 2 main diseases and/or causal pathways. The first breast cancer is early-onset, with peak incidence near age 50 years and generally more aggressive outcome. The second breast cancer is late-onset, with peak incidence near age 70 years and more indolent course. The early-onset type of breast cancer is overrepresented among AA women compared with CA women. Clinical studies suggest that the course of breast cancer may be characterized by a common pathway through sequential dormant and active states eventually resulting in clustered appearance of clinical metastases. A balance between tumor and host traits influences the pace of the common pathway. Therefore, the recurrence risk profile of a single patient is seemingly determined by a specific mix of hierarchical prognostic factors, resulting from the unique genetic, environmental, or behavioral traits of that individual, which may be affected by race-related factors. We suggest that the components of the AA versus CA disparity not attributable to socioeconomic factors are a particular case of the more general issue of host-tumor interaction and that epidemiologic and clinical views are complementary; each is observing biologic parameters, which are not completely captured by the other. A 'unifying hypothesis' incorporating findings from genetics, epidemiology, and clinical studies should be aggressively pursued.


Assuntos
Negro ou Afro-Americano/etnologia , Neoplasias da Mama/etnologia , Modelos Biológicos , População Branca/etnologia , Animais , Feminino , Humanos , Fatores de Risco , Fatores Socioeconômicos , Resultado do Tratamento
10.
Breast ; 15(1): 90-5, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16473740

RESUMO

Studies have suggested a predominance of premenopausal breast cancer in black compared to white women. The aim of the study was to compare the age specific incidence of breast cancer in Nigerian and British women. The mean age at presentation was 43.1 and 64 years for Jos (Nigeria) and Norfolk (United Kingdom), respectively. The age specific incidence rates were higher in women above 50 years compared to women less than 50 years of age in both populations. The odds of having breast cancer for women aged less than 50 years is 3.0 times higher in Norfolk (95% Confidence Interval 2.0-4.4) than Jos and 9.0 times higher for women over 50 years of age in Norfolk (95% Confidence Interval 5.3-18.3) than Jos. The age specific incidence rates are higher for postmenopausal women in both populations; with higher rates for all age groups in the United Kingdom population.


Assuntos
Neoplasias da Mama/epidemiologia , Carcinoma/epidemiologia , Adolescente , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , População Negra , Neoplasias da Mama/etnologia , Carcinoma/etnologia , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Nigéria/epidemiologia , Nigéria/etnologia , Pós-Menopausa , Estudos Retrospectivos , Reino Unido/epidemiologia , Reino Unido/etnologia , População Branca
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