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1.
J Clin Nurs ; 32(23-24): 8063-8077, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37793658

RESUMO

AIM: To investigate the mental well-being of early career nurses working in the United Kingdom during the COVID-19 pandemic, with a particular emphasis on symptoms related to post-traumatic stress disorder. DESIGN: A longitudinal survey study. METHODS: Data were acquired at three timepoints during the COVID-19 pandemic (between May 2020 and March 2021) to determine whether symptoms of post-traumatic stress disorder persisted over time. Quantitative measures of well-being were supplemented with survey data on the nurses' experiences of working during the pandemic. RESULTS: Twenty-seven per cent of participants suffered from persistent symptoms of post-traumatic stress while working as nurses during the pandemic. The nurses' baseline resilience, as well as their perception of the quality of their work environment, were significant negative predictors of symptoms of post-traumatic stress. Participants identified a range of strategies that would have helped them during the crisis, including visible, consistent and empathetic leadership, adequate training and a supportive work environment. CONCLUSION: The context of the pandemic has highlighted the vulnerability of the psychological well-being of early career nurses in the workforce. Immediate implementation of some of the more simple interventions suggested in this paper would provide early career nurses with rapid support. More complex support mechanisms should be given immediate consideration, with a view to implementation in the longer term. IMPLICATIONS FOR THE PROFESSION: This study contributes new knowledge about the psychological well-being of early career nurses working during the pandemic and suggests support mechanisms that will be crucial for the retention of these nurses in the profession. A measurement of resilience may be useful for determining the appropriate level of support to provide to early career nurses. IMPACT: Early career nurses are vulnerable to attrition from the profession. This could be exacerbated if the psychological well-being of these nurses is not being supported. Around 25% of early career nurses suffered from persistent symptoms of post-traumatic stress disorder while working as nurses during the height of the pandemic, which is a novel finding compared to other longitudinal studies. Understanding the psychological well-being of early career nurses working during a crisis period (such as a pandemic) equips nurse managers with appropriate strategies to improve nurses' emotional health and to enhance their retention within the workforce. The current findings may be of interest to clinical practitioners who have responsibility for the retention of nursing staff. No patient or public contribution. One of the authors is a statistician.


Assuntos
COVID-19 , Enfermeiras e Enfermeiros , Transtornos de Estresse Pós-Traumáticos , Humanos , COVID-19/epidemiologia , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Pandemias , Ansiedade , Saúde Mental
2.
Sci Rep ; 13(1): 11665, 2023 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-37468572

RESUMO

Quantifying neural activity in natural conditions (i.e. conditions comparable to the standard clinical patient experience) during the administration of psychedelics may further our scientific understanding of the effects and mechanisms of action. This data may facilitate the discovery of novel biomarkers enabling more personalized treatments and improved patient outcomes. In this single-blind, placebo-controlled study with a non-randomized design, we use time-domain functional near-infrared spectroscopy (TD-fNIRS) to measure acute brain dynamics after intramuscular subanesthetic ketamine (0.75 mg/kg) and placebo (saline) administration in healthy participants (n = 15, 8 females, 7 males, age 32.4 ± 7.5 years) in a clinical setting. We found that the ketamine administration caused an altered state of consciousness and changes in systemic physiology (e.g. increase in pulse rate and electrodermal activity). Furthermore, ketamine led to a brain-wide reduction in the fractional amplitude of low frequency fluctuations, and a decrease in the global brain connectivity of the prefrontal region. Lastly, we provide preliminary evidence that a combination of neural and physiological metrics may serve as predictors of subjective mystical experiences and reductions in depressive symptomatology. Overall, our study demonstrated the successful application of fNIRS neuroimaging to study the physiological effects of the psychoactive substance ketamine in humans, and can be regarded as an important step toward larger scale clinical fNIRS studies that can quantify the impact of psychedelics on the brain in standard clinical settings.


Assuntos
Alucinógenos , Ketamina , Adulto , Feminino , Humanos , Masculino , Adulto Jovem , Encéfalo/diagnóstico por imagem , Alucinógenos/farmacologia , Hemodinâmica , Método Simples-Cego
3.
Sci Rep ; 13(1): 10278, 2023 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-37355749

RESUMO

Alcohol is one of the most commonly used substances and frequently abused, yet little is known about the neural underpinnings driving variability in inhibitory control performance after ingesting alcohol. This study was a single-blind, placebo-controlled, randomized design with participants (N = 48 healthy, social drinkers) completing three study visits. At each visit participants received one of three alcohol doses; namely, a placebo dose [equivalent Blood Alcohol Concentration (BAC) = 0.00%], a low dose of alcohol (target BAC = 0.04%), or a moderate dose of alcohol (target BAC = 0.08%). To measure inhibitory control, participants completed a Go/No-go task paradigm twice during each study visit, once immediately before dosing and once after, while their brain activity was measured with time-domain functional near-infrared spectroscopy (TD-fNIRS). BAC and subjective effects of alcohol were also assessed. We report decreased behavioral performance for the moderate dose of alcohol, but not the low or placebo doses. We observed right lateralized inhibitory prefrontal activity during go-no-go blocks, consistent with prior literature. Using standard and novel metrics of lateralization, we were able to significantly differentiate between all doses. Lastly, we demonstrate that these metrics are not only related to behavioral performance during inhibitory control, but also provide complementary information to the legal gold standard of intoxication (i.e. BAC).


Assuntos
Intoxicação Alcoólica , Alcoolismo , Humanos , Consumo de Bebidas Alcoólicas , Concentração Alcoólica no Sangue , Desempenho Psicomotor , Tempo de Reação , Método Simples-Cego , Etanol/farmacologia , Encéfalo
4.
Math Biosci ; 352: 108909, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36108797

RESUMO

Clinical cancers are typically spatially and temporally heterogeneous, containing multiple microenvironmental habitats and diverse phenotypes and/or genotypes, which can interact through resource competition and direct or indirect interference. A common intratumoral evolutionary pathway, probably initiated as adaptation to hypoxia, leads to the "Warburg phenotype" which maintains high glycolytic rates and acid production, even in normoxic conditions. Since individual cancer cells are the unit of Darwinian selection, intraspecific competition dominates intratumoral evolution. Thus, elements of the Warburg phenotype become key "strategies" in competition with cancer cell populations that retain the metabolism of the parental normal cells. Here we model the complex interactions of cell populations with Warburg and parental phenotypes as they compete for access to vasculature, while subject to direct interference by Warburg-related acidosis. In this competitive environment, vasculature delivers nutrients, removes acid and necrotic detritus, and responds to signaling molecules (VEGF and TNF-α). The model is built in a nested fashion and growth parameters are derived from monolayer, spheroid, and xenograft experiments on prostate cancer. The resulting model of in vivo tumor growth reaches a steady state, displaying linear growth and coexistence of both glycolytic and parental phenotypes consistent with experimental observations. The model predicts that increasing tumor pH sufficiently early can arrest the development of the glycolytic phenotype, while decreasing tumor pH accelerates this evolution and increases VEGF production. The model's predicted dual effects of VEGF blockers in decreasing tumor growth while increasing the glycolytic fraction of tumor cells has potential implications for optimizing angiogenic inhibitors.


Assuntos
Inibidores da Angiogênese , Neoplasias da Próstata , Animais , Glicólise , Humanos , Concentração de Íons de Hidrogênio , Masculino , Fenótipo , Fator de Necrose Tumoral alfa
5.
J Imaging ; 5(3)2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34460468

RESUMO

The process of speech production, i.e., the compression of air in the lungs, the vibration activity of the larynx, and the movement of the articulators, is of great interest in phonetics, phonology, and psychology. One technique by which speech production is analysed is electropalatography, in which an artificial palate, moulded to the speaker's hard palate, is introduced in the mouth. The palate contains a grid of electrodes, which monitor the spatial and temporal pattern of contact between the tongue and the palate during speech production. The output is a time sequence of images, known as palatograms, which show the 2D distribution of electrode activation. This paper describes a series of tools for the visualisation and analysis of palatograms and their associated sound signals. The tools are developed as Matlab® routines and released as an open-source toolbox. The particular focus is the analysis of the amount and direction of left-right asymmetry in tongue-palate contact during the production of different speech sounds. Asymmetry in the articulation of speech, as measured by electropalatography, may be related to the language under consideration, the speaker's anatomy, irregularities in the palate manufacture, or speaker handedness (i.e., left or right). In addition, a pipeline for the segmentation and analysis of a three-dimensional computed tomography data set of an artificial palate is described and demonstrated. The segmentation procedure provides quantitative information about asymmetry that is due to a combination of speaker anatomy (the shape of the hard palate) and the positioning of the electrodes during manufacture of the artificial palate. The tools provided here should be useful in future studies of electropalatography.

6.
Breast ; 37: 181-186, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28781102

RESUMO

PURPOSE: Radiation therapy (RT) after breast-conserving surgery (BCS) for Ductal Carcinoma in Situ (DCIS) halves the risk of local recurrence (LR). The omission of RT is often supported by the paradigm that patients who develop LR can be salvaged with further breast-conserving therapy leading to higher rates of breast preservation and improved quality of life. However, population-based, long-term rates of breast preservation in women treated by upfront BCS ± RT are unknown. METHODS AND MATERIALS: Women diagnosed with pure DCIS from 1994 to 2003 treated with BCS ± RT in Ontario were identified. Median follow-up is 12 years. The development and treatment of LR and contralateral breast cancers were determined by administrative databases with validation. The 10-year mastectomy-free survival was calculated using the Kaplan-Meier method. The impact of RT on breast preservation was determined by propensity-adjusted cox proportional hazards model. RESULTS: The cohort includes 3303 women with DCIS; 1649 (50%) underwent BCS alone, 1654 (50%) underwent BCS + RT. Women treated by BCS alone were more likely to develop a LR compared to those treated by upfront BCS + RT (20.8% versus 15.5%, p < 0.001). Mastectomy was used to treat LR in 57.4% (197/343) of women who recurred after BCS alone and 67.6% (174/257) of those who recurred after BCS + RT. Women treated with upfront BCS + RT had higher rates of bilateral breast preservation at 10 years compared to those treated by BCS alone (87.3% vs.82.7%, p = 0.0096). CONCLUSION: Local Recurrence after BCS alone does not favor breast preservation.


Assuntos
Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Carcinoma Intraductal não Infiltrante/radioterapia , Carcinoma Intraductal não Infiltrante/cirurgia , Mastectomia Segmentar , Recidiva Local de Neoplasia/cirurgia , Segunda Neoplasia Primária/cirurgia , Terapia de Salvação , Adulto , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Mastectomia Segmentar/estatística & dados numéricos , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia/patologia , Tratamentos com Preservação do Órgão , Radioterapia Adjuvante , Fatores de Risco , Carga Tumoral
7.
Nat Commun ; 8(1): 1245, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29093438

RESUMO

Almost all genomic studies of breast cancer have focused on well-established tumours because it is technically challenging to study the earliest mutational events occurring in human breast epithelial cells. To address this we created a unique dataset of epithelial samples ductoscopically obtained from ducts leading to breast carcinomas and matched samples from ducts on the opposite side of the nipple. Here, we demonstrate that perturbations in mRNA abundance, with increasing proximity to tumour, cannot be explained by copy number aberrations. Rather, we find a possibility of field cancerization surrounding the primary tumour by constructing a classifier that evaluates where epithelial samples were obtained relative to a tumour (cross-validated micro-averaged AUC = 0.74). We implement a spectral co-clustering algorithm to define biclusters. Relating to over-represented bicluster pathways, we further validate two genes with tissue microarrays and in vitro experiments. We highlight evidence suggesting that bicluster perturbation occurs early in tumour development.


Assuntos
Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Células Epiteliais/metabolismo , Genoma Humano/genética , RNA Mensageiro/metabolismo , Transcriptoma/genética , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Proteínas de Ciclo Celular/genética , Hibridização Genômica Comparativa , Células Epiteliais/patologia , Feminino , Perfilação da Expressão Gênica , Genômica , Humanos , Células MCF-7 , Mutação , Gradação de Tumores , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas de Ligação a RNA/genética
8.
J Spinal Cord Med ; 39(1): 32-44, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25520035

RESUMO

OBJECTIVE: To assess the effectiveness of robotically assisted body weight supported treadmill training (RABWSTT) for improving cardiovascular fitness in chronic motor incomplete spinal cord injury (CMISCI). DESIGN: Pilot prospective randomized, controlled clinical trial. SETTING: Outpatient rehabilitation specialty hospital. PARTICIPANTS: Eighteen individuals with CMISCI with American Spinal Injury Association (ASIA) level between C4 and L2 and at least one-year post injury. Interventions CMISCI participants were randomized to RABWSTT or a home stretching program (HSP) three times per week for three months. Those in the home stretching group were crossed over to three months of RABWSTT following completion of the initial three month phase. OUTCOME MEASURES: Peak oxygen consumption (peak VO(2)) was measured during both robotic treadmill walking and arm cycle ergometry: twice at baseline, once at six weeks (mid-training) and twice at three months (post-training). Peak VO(2) values were normalized for body mass. RESULTS: The RABWSTT group improved peak VO(2) by 12.3% during robotic treadmill walking (20.2 ± 7.4 to 22.7 ± 7.5 ml/kg/min, P = 0.018), compared to a non-significant 3.9% within group change observed in HSP controls (P = 0.37). Neither group displayed a significant change in peak VO2 during arm cycle ergometry (RABWSTT, 8.5% (P = 0.25); HSP, 1.76% (P = 0.72)). A repeated measures analysis showed statistically significant differences between treatments for peak VO(2) during both robotic treadmill walking (P = 0.002) and arm cycle ergometry (P = 0.001). CONCLUSION: RABWSTT is an effective intervention model for improving peak fitness levels assessed during robotic treadmill walking in persons with CMISCI.


Assuntos
Terapia por Exercício/métodos , Robótica/métodos , Traumatismos da Medula Espinal/terapia , Adulto , Idoso , Terapia por Exercício/instrumentação , Humanos , Pessoa de Meia-Idade , Consumo de Oxigênio , Robótica/instrumentação , Traumatismos da Medula Espinal/reabilitação
9.
Acad Radiol ; 22(12): 1483-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26391856

RESUMO

RATIONALE AND OBJECTIVES: To evaluate the role of apparent diffusion coefficient (ADC) in distinguishing ductal carcinoma in situ (DCIS) grades and identifying microinvasive and/or invasive disease in the preoperative evaluation of patients with core biopsy-proven DCIS. MATERIALS AND METHODS: Research Ethics Board-approved study with informed consent from 81 women (age, 36-84 years) scheduled for core-biopsy with results of 82 noninvasive breast carcinomas. All patients were assessed preoperatively by diffusion sequence in addition to contrast magnetic resonance imaging (MRI). Lesion morphology and ADC values were recorded. The Kruskal-Wallis or one-way analysis of variance test and Pearson correlation coefficient were used to study the association between ADC and MRI lesion characteristics. Logistic regression analysis was used to evaluate the ability of ADC to predict the presence of invasion. RESULTS: Surgical pathology demonstrated associated invasive cancer in 26.8%, microinvasion in 14.6%, and pure DCIS in 58.5%. The minimum regions of interest (ROI)-based ADC was significantly different among the following three groups (P < .001, Kruskal-Wallis test): 0.98 × 10(-3) mm(2)/s ± 0.25 for pure DCIS, 0.82 × 10(-3) mm(2)/s ± 0.20 for DCIS with microinvasion, and 0.71 × 10(-3) mm(2)/s ± 0.27 for DCIS with invasive disease. Based on logistic regression analysis, the minimum ROI-based ADC of 0.56 × 10(-3) mm(2)/s was a significant predictor for invasive disease (odds ratio = 0.02, 95% confidence interval [0.002, 0.207], P = .001). Regardless of the field strength (1.5 vs. 3.0 T) ADC values of high-grade and non-high-grade DCIS were not significantly different. CONCLUSIONS: Pure DCIS had the highest "ROI-based" ADC measured using 1.5 T or 3.0 T. The ADC was able to identify microinvasion or invasive cancer in biopsy-proven DCIS lesions but not to distinguish the DCIS grades.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/cirurgia , Carcinoma Intraductal não Infiltrante/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Gradação de Tumores/métodos , Estudos Retrospectivos
10.
Springerplus ; 4: 335, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26185737

RESUMO

Mastectomy is effective treatment for ductal carcinoma in situ (DCIS) but some women will develop chest wall recurrence. Most chest wall recurrences that develop after mastectomy are invasive cancer and are associated with poorer prognosis. Past studies have been unable to identify factors predictive of chest wall recurrence. Therefore, it remains unclear if a subset exists of women with DCIS treated by mastectomy experience a high rate of recurrence in whom more aggressive treatment may be of benefit. We report outcomes of all women in Ontario (N = 1,546) diagnosed with pure DCIS from 1994 to 2003 treated with mastectomy without radiotherapy and evaluate factors associated with the development of chest wall recurrence. Treatments and outcomes were validated by chart review. Proportional differences were compared using Chi square analyses. Survival analyses were used to study the development of chest wall recurrence in relation to patient and tumor characteristics. Median follow-up was 10.1 years. Median age was 57.1 years. 36 patients (2.3%) developed chest wall recurrence. The 10-year actuarial chest wall recurrence-free survival rates and invasive chest wall recurrence-free survival rates were 97.6 and 98.6%, respectively. There was no difference in cumulative 10 year rates of chest wall recurrence by age at diagnosis (<40 years = 5.2%, 40-44 years = 1.3%, 45-50 years = 2.9%, >50 years = 2.1%; p = 0.19), nuclear grade (high = 3.0%, intermediate = 1.4%, low = 1.0%, unreported = 2.5%; p = 0.41), or among women with close or positive resection margins (positive = 3.0%, 2 mm or less = 1.4%, >2 mm = 1.5%, unreported = 2.8%; p = 0.51). On univariate and multivariable analysis, none of the factors were significantly associated with the development of chest wall recurrence. In this population cohort, individuals treated by mastectomy experienced low rates of chest wall recurrence. We did not identify a subset of patients with a high rate of chest wall recurrence, including those with positive margins.

11.
J Clin Oncol ; 33(18): 2035-40, 2015 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-25964246

RESUMO

PURPOSE: To determine the prognostic and predictive value of intrinsic subtyping by using immunohistochemical (IHC) biomarkers for ipsilateral breast relapse (IBR) in participants in an early breast cancer randomized trial of tamoxifen with or without breast radiotherapy (RT). PATIENTS AND METHODS: IHC analysis of estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2 (HER2), cytokeratin 5/6, epidermal growth factor receptor, and Ki-67 was conducted on 501 of 769 available blocks. Patients were classified as luminal A (n = 265), luminal B (n = 165), or high-risk subtype (luminal HER2, n = 22; HER2 enriched, n = 13; basal like, n = 30; or triple-negative nonbasal, n = 6). Median follow-up was 10 years. RESULTS: Classification by subtype was prognostic for IBR (10-year estimates: luminal A, 5.2%; luminal B, 10.5%; high-risk subtypes, 21.3%; P < .001). Luminal subtypes seemed to derive less benefit from RT (luminal A hazard ratio [HR], 0.40; luminal B HR, 0.51) than high-risk subtypes (HR, 0.13); however, the overall subtype-treatment interaction term was not significant (P = .26). In an exploratory analysis of women with clinical low-risk (age older than 60 years, T1, grade 1 or 2) luminal A tumors (n = 151), 10-year IBR was 3.1% versus 11.8% for the high-risk cohort (n = 341; P = .0063). Clinical low-risk luminal A patients had a 10-year IBR of 1.3% with tamoxifen versus 5.0% with tamoxifen plus RT (P = .42). Multivariable analysis showed that RT (HR, 0.31; P < .001), clinical risk group (HR, 2.2; P = .025), and luminal A subtype (HR, 0.25; P < .001) were significantly associated with IBR. CONCLUSION: IHC subtyping was prognostic for IBR but was not predictive of benefit from RT. Further studies may validate the exploratory finding of a low-risk luminal A group who may be spared breast RT.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/radioterapia , Recidiva Local de Neoplasia/metabolismo , Idoso , Biomarcadores Tumorais/metabolismo , Receptores ErbB/metabolismo , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Queratina-5/metabolismo , Antígeno Ki-67/metabolismo , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Modelos de Riscos Proporcionais , Receptor ErbB-2/metabolismo , Receptores de Progesterona/metabolismo , Análise Serial de Tecidos
12.
Cancer Immunol Res ; 3(2): 184-95, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25527357

RESUMO

The B7 family plays a critical role in both positive and negative regulation of immune responses by engaging a variety of receptors on lymphocytes. Importantly, blocking coinhibitory molecules using antibodies specific for CTLA-4 and PD-1 enhances tumor immunity in a subset of patients. Therefore, it is critical to understand the role of different B7 family members since they may be suitable therapeutic targets. B7-H4 is another member that inhibits T-cell function, and it is also upregulated on a variety of tumors and has been proposed to promote tumor growth. Here, we investigate the role of B7-H4 in tumor development and show that B7-H4 expression inhibits tumor growth in two mouse models. Furthermore, we show that B7-H4 expression is required for antitumor immune responses in a mouse model of mammary tumorigenesis. We found that the expression levels of B7-H4 correlate with MHC class I expression in both mouse and human samples. We show that IFNγ upregulates B7-H4 expression on mouse embryo fibroblasts and that the upregulation of B7-H4 on tumors is dependent on T cells. Notably, patients with breast cancer with increased B7-H4 expression show a prolonged time to recurrence. These studies demonstrate a positive role for B7-H4 in promoting antitumor immunity.


Assuntos
Neoplasias Mamárias Experimentais/imunologia , Microambiente Tumoral/imunologia , Inibidor 1 da Ativação de Células T com Domínio V-Set/imunologia , Animais , Biomarcadores Tumorais/metabolismo , Citotoxicidade Imunológica/imunologia , Feminino , Regulação Neoplásica da Expressão Gênica/imunologia , Granzimas/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Imunidade Celular , Interferon gama/biossíntese , Neoplasias Mamárias Experimentais/patologia , Neoplasias Mamárias Experimentais/prevenção & controle , Camundongos Transgênicos , Proteínas de Neoplasias/imunologia , Linfócitos T Citotóxicos/enzimologia , Linfócitos T Citotóxicos/imunologia , Regulação para Cima/imunologia , Inibidor 1 da Ativação de Células T com Domínio V-Set/deficiência , Inibidor 1 da Ativação de Células T com Domínio V-Set/genética
13.
Int J Radiat Oncol Biol Phys ; 90(5): 1017-24, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25220719

RESUMO

PURPOSE: Whole-breast radiation therapy (XRT) after breast-conserving surgery (BCS) for ductal carcinoma in situ (DCIS) may decrease the risk of local recurrence, but the optimal dose regimen remains unclear. Past studies administered 50 Gy in 25 fractions (conventional); however, treatment pattern studies report that hypofractionated (HF) regimens (42.4 Gy in 16 fractions) are frequently used. We report the impact of HF (vs conventional) on the risk of local recurrence after BCS for DCIS. METHODS AND MATERIALS: All women with DCIS treated with BCS and XRT in Ontario, Canada from 1994 to 2003 were identified. Treatment and outcomes were assessed through administrative databases and validated by chart review. Survival analyses were performed. To account for systematic differences between women treated with alternate regimens, we used a propensity score adjustment approach. RESULTS: We identified 1609 women, of whom 971 (60%) received conventional regimens and 638 (40%) received HF. A total of 489 patients (30%) received a boost dose, of whom 143 (15%) received conventional radiation therapy and 346 (54%) received HF. The median follow-up time was 9.2 years. The median age at diagnosis was 56 years (interquartile range [IQR], 49-65 years). On univariate analyses, the 10-year actuarial local recurrence-free survival was 86% for conventional radiation therapy and 89% for HF (P=.03). On multivariable analyses, age <45 years (hazard ratio [HR] = 2.4; 95% CI: 1.6-3.4; P<.0001), high (HR=2.9; 95% CI: 1.2-7.3; P=.02) or intermediate nuclear grade (HR=2.7; 95% CI: 1.1-6.6; P=.04), and positive resection margins (HR=1.4; 95% CI: 1.0-2.1; P=.05) were associated with an increased risk of local recurrence. HF was not significantly associated with an increased risk of local recurrence compared with conventional radiation therapy on multivariate analysis (HR=0.8; 95% CI: 0.5-1.2; P=.34). CONCLUSIONS: The risk of local recurrence among individuals treated with HF regimens after BCS for DCIS was similar to that among individuals treated with conventional radiation therapy.


Assuntos
Neoplasias da Mama/radioterapia , Carcinoma Intraductal não Infiltrante/radioterapia , Fracionamento da Dose de Radiação , Recidiva Local de Neoplasia , Idoso , Análise de Variância , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Intraductal não Infiltrante/mortalidade , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/cirurgia , Intervalo Livre de Doença , Feminino , Humanos , Mastectomia Segmentar , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Ontário , Pontuação de Propensão , Dosagem Radioterapêutica , Radioterapia Adjuvante/métodos , Radioterapia Adjuvante/estatística & dados numéricos , Retratamento/estatística & dados numéricos , Risco
14.
Breast Cancer Res Treat ; 145(3): 647-61, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24831777

RESUMO

Two-thirds of newly diagnosed hormone-dependent (HR?) breast cancers are detected in post-menopausal patients where estrone-3-sulphate (E3S) is the predominant source for tumour estradiol. Understanding intra-tumoral fate of E3S would facilitate in the identification of novel molecular targets for HR? post-menopausal breast cancer patients. Hence this study investigates the clinical expression of (i) organic anion-transporting polypeptides (OATPs), (ii) multidrug resistance protein (MRP-1), breast cancer resistance proteins (BCRP), and (iii) sulphatase (STS), 17ß-hydroxysteroid dehydrogenase (17ß-HSD-1), involved in E3S uptake, efflux and metabolism, respectively. Fluorescent and brightfield images of stained tumour sections (n = 40) were acquired at 4× and 20× magnification, respectively. Marker densities were measured as the total area of positive signal divided by the surface area of the tumour section analysed and was reported as % area (ImageJ software). Tumour, stroma and non-tumour tissue areas were also quantified (Inform software), and the ratio of optical intensity per histologic area was reported as % area/tumour, % area/stroma and % area/non-tumour. Functional role of OATPs and STS was further investigated in HR? (MCF-7, T47-D, ZR-75) and HR-(MDA-MB-231) cells by transport studies conducted in the presence or absence of specific inhibitors. Amongst all the transporters and enzymes, OATPs and STS have significantly (p < 0.0001) higher expression in HR? tumour sections with highest target signals obtained from the tumour regions of the tissues. Specific OATP-mediated E3S uptake and STS-mediated metabolism were also observed in all HR? breast cancer cells. These observations suggest the potential of OATPs as novel molecular targets for HR? breast cancers.


Assuntos
Neoplasias da Mama/patologia , Estrona/análogos & derivados , Proteínas de Membrana Transportadoras/biossíntese , 17-Hidroxiesteroide Desidrogenases/biossíntese , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/biossíntese , Linhagem Celular Tumoral , Estrona/metabolismo , Feminino , Humanos , Células MCF-7 , Proteínas Associadas à Resistência a Múltiplos Medicamentos/biossíntese , Proteínas de Neoplasias/biossíntese , Transportadores de Ânions Orgânicos/biossíntese
15.
Am J Nucl Med Mol Imaging ; 4(2): 181-92, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24753984

RESUMO

The safety, pharmacokinetics, biodistribution and radiation dosimetry of (111)In-DTPA-hEGF, an Auger electron-emitting radiopharmaceutical, were evaluated in a first-in-human trial. Dose escalation was performed in patients with EGFR-positive metastatic breast cancer who had received ≥2 prior courses of systemic treatment. (111)In-DTPA-hEGF (0.25 mg) was administered once intravenously (i.v.). Blood was collected for biochemistry/hematology testing and pharmacokinetic and immunogenicity analyses at selected times post injection (p.i.). Whole body planar images were acquired at 1, 4-6, 24 and 72 h p.i. and SPECT images at 24 and/or 72 h p.i. Macrodosimetry (MIRD) for the whole body and organs was estimated using OLINDA. Correlative radiological imaging was obtained at baseline, 1 and 3 months and then 6 monthly. Toxicity was scored using Common Terminology Criteria for Adverse Events (CTCAE)v2.0. Sixteen patients, median age 47 yr (range, 35-59), received (111)In-DTPA-hEGF as follows: 357-434 MBq (7), 754-805 MBq (3), 1,241-1,527 MBq (3) and 2,030-2,290 MBq (3). Fifteen were evaluable for toxicity. The commonest adverse events (AE) were flushing, chills, nausea, and vomiting occurring during or immediately p.i. One patient experienced Grade 3 thrombocytopenia (attributed to bone marrow infiltration by cancer). There were no other Grade 3 or 4 AEs. Maximum tolerated dose was not reached. Clear accumulation of radiopharmaceutical in at least one known site of disease was observed in 47% of patients. (111)In-DTPA-hEGF was cleared biexponentially from the blood with α-phase T½ of 0.16 ± 0.03 h and ß-phase T½ of 9.41 ± 1.93 h. (111)In-DTPA-hEGF was not immunogenic. The mean radiation dose estimates in mGy/MBq for whole body, liver, kidneys, spleen and thyroid were 0.08, 0.86, 0.74, 0.37 and 0.30, respectively. No objective antitumor responses were observed at the doses studied. In summary, administered amounts of up to 2,290 MBq (0.25 mg) of (111)In-DTPA-hEGF were well tolerated as a single i.v. injection.

16.
J Biomed Opt ; 18(12): 121513, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24343434

RESUMO

Recent advances have led to a multitude of image modalities being used for visualization of tissue stiffness. High-resolution images of tissue stiffness are desirable, as they have the potential to provide useful diagnostic information. A noncontact optical imaging method has the attractions of low cost, simplicity, and utility when skin contact is undesirable. However, previous optical techniques have required the application of paint or ink to the surface of the skin and so have required contact. Therefore, the present study assessed the feasibility of tracking skin surface topography to produce elastograms. The study showed, by analyzing a variety of silicone skin surface replicas from various body sites of subjects of different ages, that skin surface elastography by tracking surface topography would be feasible. The study further showed that the quality of the strain images can be optimized by measuring skin line pattern frequency. Skin samples with high skin line frequency will achieve best spatial resolution, in the order of 1 mm, comparable to contact techniques reported previously. A mechanically inhomogeneous silicone replica was then imaged, illustrating the technique's ability to detect strain contrast. Finally, the feasibility of implementing the technique in vivo was illustrated using a single pigmented skin lesion.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Elasticidade/fisiologia , Fenômenos Fisiológicos da Pele , Adulto , Técnicas de Imagem por Elasticidade/instrumentação , Feminino , Humanos , Nevo/patologia , Nevo/fisiopatologia , Imagens de Fantasmas , Elastômeros de Silicone , Pele/patologia , Pele/fisiopatologia , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/fisiopatologia
17.
Int J Radiat Oncol Biol Phys ; 86(3): 491-7, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23708085

RESUMO

PURPOSE: To report the outcomes of a population of women with ductal carcinoma in situ (DCIS) treated with breast-conserving surgery and radiation and to evaluate the independent effect of boost radiation on the development of local recurrence. METHODS AND MATERIALS: All women diagnosed with DCIS and treated with breast-conserving surgery and radiation therapy in Ontario from 1994 to 2003 were identified. Treatments and outcomes were identified through administrative databases and validated by chart review. The impact of boost radiation on the development of local recurrence was determined using survival analyses. RESULTS: We identified 1895 cases of DCIS that were treated by breast-conserving surgery and radiation therapy; 561 patients received boost radiation. The cumulative 10-year rate of local recurrence was 13% for women who received boost radiation and 12% for those who did not (P=.3). The 10-year local recurrence-free survival (LRFS) rate among women who did and who did not receive boost radiation was 88% and 87%, respectively (P=.27), 94% and 93% for invasive LRFS (P=.58), and was 95% and 93% for DCIS LRFS (P=.31). On multivariable analyses, boost radiation was not associated with a lower risk of local recurrence (hazard ratio = 0.82, 95% confidence interval 0.59-1.15) (P=.25). CONCLUSIONS: Among a population of women treated with breast-conserving surgery and radiation for DCIS, additional (boost) radiation was not associated with a lower risk of local or invasive recurrence.


Assuntos
Neoplasias da Mama/radioterapia , Carcinoma Intraductal não Infiltrante/radioterapia , Recidiva Local de Neoplasia/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Neoplasias da Mama/prevenção & controle , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/prevenção & controle , Carcinoma Intraductal não Infiltrante/cirurgia , Intervalo Livre de Doença , Fracionamento da Dose de Radiação , Feminino , Seguimentos , Humanos , Mastectomia Segmentar , Corpo Clínico Hospitalar/estatística & dados numéricos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Ontário , Radioterapia Adjuvante/métodos , Retratamento/métodos , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
18.
Breast Cancer Res Treat ; 138(2): 581-90, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23456231

RESUMO

Ductal carcinoma in situ (DCIS), a non-invasive breast cancer, is usually treated by breast-conserving surgery (BCS). Randomized trials prove that the addition of radiotherapy (XRT) leads to lower rates of recurrence. Despite the evidence, half of women do not receive XRT after BCS. It is unknown how well clinicians identify women with low risk DCIS for treatment by BCS alone or to what extent women with DCIS develop recurrent cancer due to the omission of radiotherapy. We report the outcomes of a population of women with DCIS treated with BCS, alone or with radiotherapy, and evaluate the effectiveness of each therapeutic approach. All women diagnosed with DCIS and treated with BCS, alone or with radiotherapy in Ontario from 1994 to 2003 were identified. Treatments and outcomes were validated by chart review. Survival analyses were used to study the development of local recurrence (LR) in relation to patient and tumor characteristics and the use of radiotherapy. The cohort included 3,762 women treated with breast-conserving therapy; 1,895 of whom (50 %) also received radiation. At 10 years median follow-up, LR developed in 233 (12 %) women who received radiotherapy and in 363 (19 %) of women who did not (p < 0.0001). The 10-year actuarial LR rate for women who did and did not receive radiotherapy was 12.7 and 20.0 % (p < 0.0001). Differences were significant for both for invasive LR (7.0 vs. 10.0 %, p < 0.0001) and for DCIS recurrence (6.1 vs. 10.8 %, p < 0.0001). We estimate that 22 % of recurrences diagnosed in Ontario women treated for DCIS between 1994 and 2003 would have been prevented if all patients had received radiotherapy. The omission of radiotherapy after BCS for DCIS resulted in substantive recurrences that might have been avoided with treatment. Additional markers are needed to identify a low risk group in whom radiation can be safely omitted.


Assuntos
Neoplasias da Mama/epidemiologia , Carcinoma Intraductal não Infiltrante/epidemiologia , Recidiva Local de Neoplasia/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Carcinoma Intraductal não Infiltrante/radioterapia , Carcinoma Intraductal não Infiltrante/cirurgia , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Humanos , Incidência , Mastectomia Segmentar , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Ontário/epidemiologia , População , Risco , Resultado do Tratamento , Adulto Jovem
19.
Skin Res Technol ; 19(1): e37-44, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22309091

RESUMO

BACKGROUND/AIMS: Elastography is a promising new medical imaging modality, displaying spatial distribution of biomechanical properties such as local tissue strain response to an applied stress. To develop a reproducible test protocol for skin elastography, the effect of various parameters on skin stiffness measurements was investigated. METHODS: The parameters investigated were: history of skin loading before test loading (preconditioning), direction of test loading (anisotropy) and posture (pre-stress). If a sample of skin is loaded, its stiffness will temporarily change. Finally, the reproducibility of skin stiffness and anisotropy measurements, using the developed techniques, was investigated. RESULTS: By measuring how the stiffness changed with different time delays between loading cycles, the time required for healthy skin to return to its original pre-loaded state was in the region of 125 s. A second finding, which supports and extends previous work, was that skin stiffness varied with direction, by an approximate factor of 2, and that anisotropy was less apparent with preconditioned skin than non-preconditioned skin. Study of the effect of posture showed that care needs to be taken over which stiffness measure is used. For example, measurement of the load at a given displacement was found to be highly dependent on posture, whereas measurement of the phase III stiffness was independent of posture. CONCLUSION: It was shown that when the measurement variables and methods of analysis were standardised, skin stiffness could be measured reproducibly enough to distinguish between the stiffest and softest directions, and that these methods allowed formation of skin elastograms free from confounding influences.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Técnicas de Imagem por Elasticidade/normas , Fenômenos Fisiológicos da Pele , Resistência à Tração/fisiologia , Adulto , Anisotropia , Fenômenos Biomecânicos/fisiologia , Técnicas de Imagem por Elasticidade/instrumentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Postura/fisiologia , Estudos Prospectivos , Reprodutibilidade dos Testes , Estresse Mecânico , Suporte de Carga/fisiologia , Adulto Jovem
20.
Ann Surg Oncol ; 20(1): 133-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23064777

RESUMO

PURPOSE: to determine the frequency of malignancy in subsequent breast excisions following core-needle biopsy (CNB) diagnosis of pure flat epithelial atypia (pFEA) and to evaluate the imaging features of the associated tumors. MATERIALS AND METHODS: Retrospective review of 8,996 image-guided CNB (2002-2010) identified 115 cases of FEA not associated with other atypia. Patients with history of breast cancer or radiation therapy were excluded. One hundred four cases (women) with pFEA (mean age 51 years, range 29-77 years) were reviewed. Stereotactic CNB was performed in 79 (76%) cases and ultrasound (US)-guided CNB in 25 (24%) cases. In 99 cases 14G needles were used, and 10G vacuum-assisted devices were used in 5 cases. Ninety-four patients had subsequent excision. Ten patients declined excision, and imaging follow-up (mean of 36 months) is available. The upgrade rate of pFEA was defined as the number of patients diagnosed with invasive carcinoma (IC) or carcinoma in situ (CIS) divided by the total number of patients. RESULTS: 10 of 104 (9.6%) patients were diagnosed with cancer: 9 presented as calcifications (89% fine pleomorphic and amorphous) and 1 case as a mammographically occult mass. The size of calcifications was not statistically significant (P=0.358). Five cases had ductal carcinoma in situ (DCIS) and five cases had IC (ductal and lobular) presenting as amorphous and pleomorphic calcifications. CONCLUSIONS: The upgrade rate of pFEA in our series was 9.6%. The presence of 4.8% of invasive cancers is substantial and warrants continuing management with surgical excision in all cases.


Assuntos
Neoplasias da Mama/patologia , Mama/patologia , Carcinoma in Situ/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/patologia , Adulto , Idoso , Biópsia por Agulha , Neoplasias da Mama/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Carcinoma in Situ/diagnóstico por imagem , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Lobular/diagnóstico por imagem , Epitélio/patologia , Feminino , Humanos , Mamografia , Pessoa de Meia-Idade , Gradação de Tumores , Estudos Retrospectivos
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