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1.
Vox Sang ; 118(8): 605-615, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37191161

RESUMO

BACKGROUND AND OBJECTIVES: In Canada, the time deferral for gay, bisexual and other men who have sex with men (gbMSM) to donate blood has gradually decreased. In September 2022, this deferral was replaced with sexual behaviour-based screening for all donors. We investigate how data from targeted research programmes addressed knowledge gaps to support this change. MATERIALS AND METHODS: We conducted a scoping review describing the Canadian literature available before the research programmes relating to (1) behavioural indicators of HIV risk and (2) attitudes to blood donation among gbMSM, current donors and the general population. We summarize the targeted research programmes, their outputs and impact to date. RESULTS: For question 1, five projects met inclusion criteria. For question 2, three articles met inclusion criteria. Knowledge gaps identified were insufficient evidence of HIV incidence in gbMSM who met other donor eligibility criteria and scant data on opinions and views of blood donation and screening criteria for sexual risk behaviours. The research programmes funded 19 projects at 11 different research sites involving over 100 individual researchers/collaborators resulting in 19 peer-reviewed publications to date. Leveraging existing gbMSM cohorts yielded relevant HIV incidence data to inform safety modelling studies. Findings indicated that sexual behaviour-based screening was acceptable to gbMSM and donors, and donor discomfort around specific questions could be mitigated with clear explanations. CONCLUSION: Targeted research programmes filled critical knowledge gaps and informed a change to gender-neutral, sexual behaviour-based screening for all donors. Findings supported successful implementation of these changes with research-informed staff training.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Masculino , Humanos , Homossexualidade Masculina , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Canadá/epidemiologia , Comportamento Sexual , Doadores de Sangue
2.
Br J Cancer ; 125(2): 299-304, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34017085

RESUMO

BACKGROUND: The optimal time to deliver adjuvant chemotherapy has not been defined. METHODS: A retrospective study of consecutive patients receiving adjuvant anthracycline and/or taxane 1993-2010. Primary endpoint included 5-year disease-free survival (DFS) in patients commencing chemotherapy <31 versus ≥31 days after surgery. Secondary endpoints included 5-year overall survival (OS) and sub-group analysis by receptor status. RESULTS: We identified 2003 eligible patients: 1102 commenced chemotherapy <31 days and 901 ≥31 days after surgery. After a median follow-up of 115 months, there was no difference in 5-year DFS rate with chemotherapy <31 compared to ≥31 days after surgery in the overall population (81 versus 82% hazard ratio (HR) 1.15, 95% confidence interval (95% CI) 0.92-1.43, p = 0.230). The 5-year OS rate was similar in patients who received chemotherapy <31 or ≥31 days after surgery (90 versus 91%, (HR 1.21, 95% CI 0.89-1.64, p = 0.228). For 250 patients with triple-negative breast cancer OS was significantly worse in patients who received chemotherapy ≥31 versus <31 days (HR = 2.18, 95% CI 1.11-4.30, p = 0.02). DISCUSSION: Although adjuvant chemotherapy ≥31 days after surgery did not affect DFS or OS in the whole study population, in TN patients, chemotherapy ≥31 days after surgery significantly reduced 5-year OS; therefore, delays beyond 30 days in this sub-group should be avoided.


Assuntos
Antraciclinas/uso terapêutico , Neoplasias da Mama Masculina/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Hidrocarbonetos Aromáticos com Pontes/uso terapêutico , Taxoides/uso terapêutico , Adulto , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Neoplasias da Mama Masculina/patologia , Neoplasias da Mama Masculina/cirurgia , Quimioterapia Adjuvante , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Reino Unido
3.
Am J Physiol Lung Cell Mol Physiol ; 311(6): L1076-L1081, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27760764

RESUMO

Bronchopulmonary dysplasia (BPD) is often complicated by pulmonary hypertension (PH). We investigated three biomarkers potentially suitable as screening markers for extremely preterm infants at risk of BPD-associated PH. In this prospective observational cohort study conducted in a tertiary neonatal intensive care unit, 83 preterm infants with BPD born <28-wk gestation and still inpatients at 36-wk corrected age received an echocardiogram and blood tests of B-type natriuretic peptide (BNP), troponin I, and YKL-40. Infants were analyzed according to echocardiographic evidence of tricuspid regurgitation (TR). Thirty infants had evidence of TR on echocardiogram at 36-wk corrected age. Infants with or without TR had similar baseline demographics: mean ± SD gestational age 261 ± 12 vs. 261 ± 11 wk and birth weight 830 ± 206 vs. 815 ± 187 g, respectively. There was no difference in duration of respiratory support. The right ventricular systolic pressure of infants with evidence of TR was 40 ± 16 mmHg. BNP was the only biomarker that proved to be significantly higher in infants with evidence of TR: median (interquartile range) serum level 54.5 (35-105) vs. 41.5 (30-59) pg/ml, P = 0.043. Subgroup analysis of infants with severe BPD requiring discharge on home oxygen or BPD-related mortality revealed similar results. There was no difference between groups for troponin I and YKL-40. In conclusion, increased serum levels of BNP were associated with evidence of TR at 36-wk corrected gestational age in extremely preterm infants, suggesting a potential role as a screening biomarker for BPD-associated PH.


Assuntos
Displasia Broncopulmonar/sangue , Proteína 1 Semelhante à Quitinase-3/sangue , Hipertensão Pulmonar/sangue , Lactente Extremamente Prematuro/sangue , Peptídeo Natriurético Encefálico/sangue , Troponina I/sangue , Biomarcadores/sangue , Displasia Broncopulmonar/complicações , Demografia , Feminino , Humanos , Hipertensão Pulmonar/complicações , Masculino , Ventilação Pulmonar , Fatores de Risco
4.
Mol Cell Proteomics ; 13(12): 3308-19, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25146974

RESUMO

The discovery of new functions for platelets, particularly in inflammation and immunity, has expanded the role of these anucleate cell fragments beyond their primary hemostatic function. Here, four in-depth human platelet proteomic data sets were generated to explore potential new functions for platelets based on their protein content and this led to the identification of 2559 high confidence proteins. During a more detailed analysis, consistently high expression of the proteasome was discovered, and the composition and function of this complex, whose role in platelets has not been thoroughly investigated, was examined. Data set mining resulted in identification of nearly all members of the 26S proteasome in one or more data sets, except the ß5 subunit. However, ß5i, a component of the immunoproteasome, was identified. Biochemical analyses confirmed the presence of all catalytically active subunits of the standard 20S proteasome and immunoproteasome in human platelets, including ß5, which was predominantly found in its precursor form. It was demonstrated that these components were assembled into the proteasome complex and that standard proteasome as well as immunoproteasome subunits were constitutively active in platelets. These findings suggest potential new roles for platelets in the immune system. For example, the immunoproteasome may be involved in major histocompatibility complex I (MHC I) peptide generation, as the MHC I machinery was also identified in our data sets.


Assuntos
Plaquetas/imunologia , Complexo de Endopeptidases do Proteassoma/imunologia , Subunidades Proteicas/imunologia , Proteoma/imunologia , Plaquetas/química , Plaquetas/metabolismo , Linhagem Celular Tumoral , Mineração de Dados , Expressão Gênica , Células HEK293 , Antígenos de Histocompatibilidade Classe I/química , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Imunidade Inata , Anotação de Sequência Molecular , Cultura Primária de Células , Complexo de Endopeptidases do Proteassoma/química , Complexo de Endopeptidases do Proteassoma/genética , Subunidades Proteicas/química , Subunidades Proteicas/genética , Proteoma/química , Proteoma/genética
5.
Platelets ; 22(1): 65-73, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21133649

RESUMO

Elevated levels of plasma homocysteine (Hcy) are an independent risk factor for cardiovascular disease and thrombosis. The molecular basis for this phenomenon is not known but may relate to modification of cell surface thiols. The platelet specific integrin α(IIb)ß3 is a cysteine-rich cell adhesion molecule that plays a critical role in platelet aggregation and adhesion in haemostasis and thrombosis. In this study, we looked for evidence of a homocysteine-induced modification of α(IIb)ß3 using a fluorescently labeled PAC-1 antibody that recognizes the activated conformation of the integrin on the platelet surface. We show that exogenous Hcy (10-100 µM) and homocysteine thiolactone (HcyTL) (10-100 µM) increased PAC-1 binding to platelets in a concentration dependent manner in vitro. In parallel, we show subjects with clinical hyperhomocysteinemia exhibit a greater degree of activation of α(IIb)ß3 compared to age-matched controls. These findings demonstrate that circulating Hcy can modulate the activation state of the platelet integrin α(IIb)ß3, a key player in platelet aggregation and thrombosis.


Assuntos
Homocisteína/metabolismo , Hiper-Homocisteinemia/metabolismo , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Trombose/metabolismo , Anticorpos/metabolismo , Sítios de Ligação de Anticorpos/efeitos dos fármacos , Plaquetas/metabolismo , Estudos de Casos e Controles , Feminino , Homocisteína/análogos & derivados , Homocisteína/farmacologia , Humanos , Hiper-Homocisteinemia/complicações , Hiper-Homocisteinemia/fisiopatologia , Integrinas/metabolismo , Masculino , Ativação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Fatores de Risco , Compostos de Sulfidrila/metabolismo , Trombose/etiologia , Trombose/fisiopatologia
6.
Mol Cell Proteomics ; 8(5): 887-903, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19119137

RESUMO

Nitroxyl (HNO) exhibits many important pharmacological effects, including inhibition of platelet aggregation, and the HNO donor Angeli's salt has been proposed as a potential therapeutic agent in the treatment of many diseases including heart failure and alcoholism. Despite this, little is known about the mechanism of action of HNO, and its effects are rarely linked to specific protein targets of HNO or to the actual chemical changes that proteins undergo when in contact with HNO. Here we study the presumed major molecular target of HNO within the body: protein thiols. Cysteine-containing tryptic peptides were reacted with HNO, generating the sulfinamide modification and, to a lesser extent, disulfide linkages with no other long lived intermediates or side products. The sulfinamide modification was subjected to a comprehensive tandem mass spectrometric analysis including MS/MS by CID and electron capture dissociation as well as an MS(3) analysis. These studies revealed a characteristic neutral loss of HS(O)NH2 (65 Da) that is liberated from the modified cysteine upon CID and can be monitored by mass spectrometry. Upon storage, partial conversion of the sulfinamide to sulfinic acid was observed, leading to coinciding neutral losses of 65 and 66 Da (HS(O)OH). Validation of the method was conducted using a targeted study of nitroxylated glyceraldehyde-3-phosphate dehydrogenase extracted from Angeli's salt-treated human platelets. In these ex vivo experiments, the sample preparation process resulted in complete conversion of sulfinamide to sulfinic acid, making this the sole subject of further ex vivo studies. A global proteomics analysis to discover platelet proteins that carry nitroxyl-induced modifications and a mass spectrometric HNO dose-response analysis of the modified proteins were conducted to gain insight into the specificity and selectivity of this modification. These methods identified 10 proteins that are modified dose dependently in response to HNO, whose functions range from metabolism and cytoskeletal rearrangement to signal transduction, providing for the first time a possible mechanistic link between HNO-induced modification and the physiological effects of HNO donors in platelets.


Assuntos
Plaquetas/metabolismo , Proteínas Sanguíneas/análise , Espectrometria de Massas/métodos , Óxidos de Nitrogênio/metabolismo , Processamento de Proteína Pós-Traducional , Sequência de Aminoácidos , Proteínas Sanguíneas/química , Cisteína/metabolismo , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/metabolismo , Humanos , Cinética , Dados de Sequência Molecular , Peptídeos/química , Proteoma/análise , Proteômica , Reprodutibilidade dos Testes , Compostos de Sulfônio/metabolismo , Espectrometria de Massas em Tandem
7.
Breast Cancer Res Treat ; 123(3): 829-36, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20697803

RESUMO

Cyclo-oxygenase 2 (COX-2) is implicated in the regulation of aromatase transcription in malignant breast tissue and has been considered as a potential target for tissue specific aromatase suppression. We initiated a randomised controlled pre-surgical study of celecoxib versus no treatment in women with primary breast cancer to determine the effects of COX-2 inhibition on markers of biological response. Postmenopausal women (50-80 years of age) with stage I or II, primary breast cancer, were randomised 2:1 to receive 400 mg/day celecoxib or no treatment for 14 days prior to surgery. A core biopsy was obtained pre- and post-treatment. Paired baseline and endpoint biopsies were analysed for Ki67, apoptosis, COX-2, CD31, estrogen receptor (ER) and progesterone receptor (PgR). Comparisons between the treatment groups were conducted using the Mann-Whitney test with a two-sided 5% significance. Of the 25 patients treated, 23 had evaluable data and 19 (83%) were ER positive. Overall the geometric mean change in Ki67, the primary end point, relative to baseline in the celecoxib arm was -16.6% (P = 0.056). The change in the no-treatment group was -8.1% (P = 0.24). There was no statistically significant difference in the change between the two groups. Celecoxib did not significantly affect apoptosis, COX-2, ER or PgR expression. There is only modest evidence for a biological effect of celecoxib in primary breast cancer. However, the trend towards a reduction in Ki67 in ER-positive breast cancer warrants further investigations in a larger cohort of patients.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Inibidores de Ciclo-Oxigenase 2/administração & dosagem , Ciclo-Oxigenase 2/metabolismo , Pirazóis/administração & dosagem , Sulfonamidas/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Apoptose/efeitos dos fármacos , Biópsia , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Celecoxib , Proliferação de Células/efeitos dos fármacos , Quimioterapia Adjuvante , Esquema de Medicação , Feminino , Humanos , Antígeno Ki-67/metabolismo , Londres , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estadiamento de Neoplasias , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Pós-Menopausa , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Fatores de Tempo , Resultado do Tratamento
8.
Expert Rev Mol Med ; 12: e30, 2010 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-20860882

RESUMO

In recent years, the technology and methods widely available for mass spectrometry (MS)-based proteomics have increased in power and potential, allowing the study of protein-level processes occurring in biological systems. Although these methods remain an active area of research, established techniques are already helping answer biological questions. Here, this recent evolution of MS-based proteomics and its applications are reviewed, including standard methods for protein and peptide separation, biochemical fractionation, quantitation, targeted MS approaches such as selected reaction monitoring, data analysis and bioinformatics. Recent research in many of these areas reveals that proteomics has moved beyond simply cataloguing proteins in biological systems and is finally living up to its initial potential - as an essential tool to aid related disciplines, notably health research. From here, there is great potential for MS-based proteomics to move beyond basic research, into clinical research and diagnostics.


Assuntos
Pesquisa Biomédica/tendências , Espectrometria de Massas/tendências , Proteômica/tendências , Humanos
9.
Transfusion ; 49(9): 1944-55, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19497060

RESUMO

BACKGROUND: The term platelet storage lesion (PSL) describes the structural and biochemical changes in platelets (PLTs) during storage. These are typified by alterations of morphologic features and PLT metabolism leading to reduced functionality and hence reduced viability for transfusion. While the manifestations of the storage lesion are well characterized, the biochemical pathways involved in the initiation of this process are unknown. STUDY DESIGN AND METHODS: A complementary proteomic approach has recently been applied to analyze changes in the PLT proteome during storage. By employing stringent proteomic criteria, 12 proteins were identified as significantly and consistently changing in relative concentration over a 7-day storage period. Microscopy, Western blot analysis, flow cytometry, and PLT functionality analyses were used to unravel the involvement of a subset of these 12 proteins, which are connected through integrin signaling in one potential signaling pathway underlying storage lesion development. RESULTS: Microscopic analysis revealed changes in localization of glycoprotein IIIa, Rap1, and talin during storage. Rap1 activation was observed to correlate with expression of the PLT activation marker CD62P. PLTs incubated for 7 days with the PI3-kinase inhibitor LY294002 showed diminished Rap1 activation as well as a moderate reduction in integrin alphaIIbbeta3 activation and release of alpha-granules. Furthermore, this inhibitor seemed to improve PLT integrity and quality during storage as several in vitro probes showed a deceleration of PLT activation. CONCLUSION: These results provide the first evidence for a signaling pathway mediating PSL in which PI3-kinase-dependent Rap1 activation leads to integrin alphaIIbbeta3 activation and PLT degranulation.


Assuntos
Plaquetas/metabolismo , Preservação de Sangue/efeitos adversos , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Proteínas rap1 de Ligação ao GTP/metabolismo , Plaquetas/efeitos dos fármacos , Western Blotting , Cromonas/farmacologia , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Citometria de Fluxo , Imunofluorescência , Microscopia de Fluorescência , Morfolinas/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Transdução de Sinais/efeitos dos fármacos
10.
Breast ; 16(4): 359-66, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17509879

RESUMO

Patients with metastatic breast cancer (MBC) are increasingly offered third line chemotherapy. We have reviewed the response rate (RR), time to progression (TTP) and survival of 149 patients in this setting and have investigated factors that influence their outcome. The RR, TTP and survival were 30%, 4 and 8 months, respectively, and should serve as a benchmark for future studies. Response to previous chemotherapy was the only independent variable predicting RR, TTP and survival, p=0.025, 0.04 and 0.004, respectively. Thirty-two percent of patients did not respond to the first two lines of chemotherapy and had a lower RR and a significantly shorter TTP and survival. In conclusion, third line chemotherapy for MBC is sometimes effective in patients who have responded to previous chemotherapy. Patients who do not respond to the first two lines of chemotherapy should be considered for clinical trials or supportive care.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Ósseas/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Vísceras , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/secundário , Neoplasias da Mama/patologia , Neoplasias do Sistema Nervoso Central/secundário , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Neoplasias Cutâneas/secundário , Resultado do Tratamento
11.
Clin Cancer Res ; 12(3 Pt 2): 1024s-1030s, 2006 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-16467120

RESUMO

The study of changes in proliferation as a marker of treatment benefit during presurgical endocrine treatment of breast cancer has become increasingly popular, particularly using the nuclear marker Ki67, and holds the potential for prioritizing new treatments for full clinical development. There are weakly significant relationships between Ki67 change and clinical response that differ according to data handling. In the neoadjuvant Immediate Preoperative Anastrozole, Tamoxifen, or Combined with Tamoxifen trial, suppression of Ki67 at both 2 and 12 weeks was greater with the aromatase inhibitor anastrozole than with either tamoxifen or the combination of anastrozole and tamoxifen. We report here that absolute values of Ki67 after 2 weeks were also significantly lower with anastrozole than with tamoxifen and the combination. This indicates that it may be possible to make such comparisons using surgical samples only. We argue that these changes in proliferation and concurrent changes in apoptosis may be expected to be more predictive of adjuvant benefit from endocrine therapy than clinical response.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/análise , Neoplasias da Mama/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Terapia Neoadjuvante , Anastrozol , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Humanos , Marcação In Situ das Extremidades Cortadas , Antígeno Ki-67/efeitos dos fármacos , Antígeno Ki-67/metabolismo , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Nitrilas/uso terapêutico , Prognóstico , Tamoxifeno/uso terapêutico , Triazóis/uso terapêutico
12.
J Clin Oncol ; 23(22): 5108-16, 2005 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-15998903

RESUMO

PURPOSE: The Immediate Preoperative Anastrozole, Tamoxifen, or Combined With Tamoxifen (IMPACT) trial was designed to test the hypothesis that the clinical and/or biologic effects of neoadjuvant tamoxifen compared with anastrozole and with the combination of tamoxifen and anastrozole before surgery in postmenopausal women with estrogen receptor (ER) -positive, invasive, nonmetastatic breast cancer might predict for outcome in the Arimidex, Tamoxifen Alone or in Combination (ATAC) adjuvant therapy trial. PATIENTS AND METHODS: Postmenopausal women with ER-positive, invasive, nonmetastatic, and operable or locally advanced potentially operable breast cancer were randomly assigned to neoadjuvant tamoxifen (20 mg daily), anastrozole (1 mg daily), or a combination of tamoxifen and anastrozole for 3 months. The tumor objective response (OR) was assessed by both caliper and ultrasound. Comparisons were also made of clinical response with ultrasound response, actual and feasible surgery with feasible surgery at baseline, OR in human epidermal growth factor receptor 2 (HER2)-positive cancers, and tolerability. RESULTS: There were no significant differences in OR in the intent-to-treat population between patients receiving tamoxifen, anastrozole, or the combination. In patients who were assessed as requiring mastectomy at baseline (n = 124), 44% of patients received breast-conserving surgery (BCS) after anastrozole compared with 31% of patients after tamoxifen (P = .23); this difference became significant for patients who were deemed feasible for BCS by their surgeon (46% v 22%, respectively; P = .03). The OR for patients with HER2-positive cancer (n = 34) was 58% for anastrozole compared with 22% for tamoxifen (P = .18). All treatments were well tolerated. CONCLUSION: Neoadjuvant anastrozole is as effective and well tolerated as tamoxifen in ER-positive operable breast cancer in postmenopausal women, but the hypothesis that clinical outcome might predict for long-term outcome in adjuvant therapy was not fulfilled.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Nitrilas/uso terapêutico , Tamoxifeno/uso terapêutico , Triazóis/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Anastrozol , Antineoplásicos Hormonais/administração & dosagem , Neoplasias da Mama/cirurgia , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Nitrilas/administração & dosagem , Razão de Chances , Placebos , Pós-Menopausa , Tamoxifeno/administração & dosagem , Resultado do Tratamento , Triazóis/administração & dosagem
13.
J Clin Oncol ; 23(11): 2477-92, 2005 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-15767642

RESUMO

PURPOSE: To investigate the relationships between biomarker changes in breast cancer during neoadjuvant (preoperative) endocrine therapy. PATIENTS AND METHODS: The IMPACT trial compared the preoperative use of tamoxifen with anastrozole alone or in combination in postmenopausal women (n = 330) with primary breast cancer. Biomarkers were measured in tumor biopsy specimens taken at baseline, and after 2 and 12 weeks of treatment. RESULTS: 52 (93%) of 56, 46 (85%) of 54, and 37 (84%) of 44 patients in the anastrozole, tamoxifen, and combination groups, respectively. There was a significantly greater suppression of Ki67 in the anastrozole-treated group than in the tamoxifen- or combination-treated groups, which is parallel to the greater efficacy seen for anastrozole over these two treatments in the Arimidex, Tamoxifen, Alone or in Combination adjuvant trial. A positive relationship was noted between estrogen-receptor level and Ki67 suppression in all patients. Ki67 was reduced to a greater extent in progesterone receptor-positive tumors compared with progesterone receptor-negative tumors. HER-2-negative tumors tended to show a greater reduction in Ki67 compared with HER-2-positive tumors, but the difference was only significant in the tamoxifen group after 2 weeks, and in the anastrozole group after 12 weeks. CONCLUSION: These results confirm the value of Ki67 as a molecular marker, and provide information regarding the relationships between treatment-induced changes in Ki67 and other important biomarkers. Studies such as this should help integrate agents targeted at growth factor signaling with endocrine agents in breast cancer.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/análise , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Antígeno Ki-67/análise , Nitrilas/uso terapêutico , Tamoxifeno/uso terapêutico , Triazóis/uso terapêutico , Idoso , Anastrozol , Antineoplásicos Hormonais/administração & dosagem , Neoplasias da Mama/cirurgia , Proliferação de Células , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Nitrilas/administração & dosagem , Pós-Menopausa , Valor Preditivo dos Testes , Receptor ErbB-2/análise , Tamoxifeno/administração & dosagem , Resultado do Tratamento , Triazóis/administração & dosagem
14.
Clin Cancer Res ; 11(2 Pt 2): 951s-8s, 2005 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-15701892

RESUMO

PURPOSE: Neoadjuvant (preoperative) therapy for breast cancer may allow for the development of intermediate markers of treatment benefit, thereby circumventing the need for efficacy trials of adjuvant therapy, which require much larger patient numbers and longer follow-up. The aim of this study--as part of the Immediate Preoperative "Arimidex" (anastrozole), Tamoxifen, or Arimidex Combined with Tamoxifen (IMPACT) trial (n = 330)--was to test the hypotheses that changes in Ki-67 after 2 weeks and/or 12 weeks: (i) differed between treatments, (ii) predicted clinical tumor response, and/or (iii) may predict long-term outcome differences between treatments in adjuvant therapy. EXPERIMENTAL DESIGN: The Arimidex, Tamoxifen, Alone or in Combination (ATAC) trial compared these same agents in the adjuvant setting. Biomarkers were measured in biopsy specimens taken before and after 2 and 12 weeks of treatment. RESULTS: Suppression of the proliferation marker Ki-67 after 2 and 12 weeks was significantly greater with anastrozole than with tamoxifen (P = 0.004 and P < 0.001) but was similar between tamoxifen and the combination (P = 0.600 and P = 0.912). This result closely parallels that seen for the relative recurrence-free survival with the treatments after a median follow-up of 31 months in the ATAC trial in 9,366 patients. Against expectations, apoptosis was not increased in any of the treatment arms. CONCLUSIONS: The data indicate that short-term changes in proliferation in the neoadjuvant setting may be able to predict outcome during adjuvant use of the same treatments. If this can be confirmed, these findings could lead to a profound change in approaches to drug development in breast cancer. The data indicate that estrogen is not an important survival factor for human breast cancer cells.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Antígeno Ki-67/metabolismo , Recidiva Local de Neoplasia/tratamento farmacológico , Idoso , Anastrozol , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Quimioterapia Adjuvante , Intervalo Livre de Doença , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Terapia Neoadjuvante , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Nitrilas/administração & dosagem , Taxa de Sobrevida , Tamoxifeno/administração & dosagem , Resultado do Tratamento , Triazóis/administração & dosagem
16.
Thromb Res ; 139: 50-5, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26916296

RESUMO

Studies of sex-dependent differences in platelet aggregation and glycoprotein (GP)IIb/IIIa activation have demonstrated that platelets from females are more sensitive to agonists than those from males. To date, there is little understanding of these differences at a molecular level. Here, sex differences in reactivity of platelets from 86 women and 86 men were investigated. Platelet degranulation (CD62P expression) and activation of GPIIb/IIIa (PAC-1 binding), with and without ADP, were assessed. Extent of shape change (ESC) in response to ADP was measured. Basal CD62P and PAC-1 expression did not differ between the sexes. In response to ADP activation, mean PAC-1 binding in platelets from female donors was 17.9±3.5% vs. 14.0±4.1% in platelets from male donors, and ESC was significantly greater in platelets from females (p<0.05). Evaluation of basal expression of signaling molecules along the ADP receptor pathway leading to GPIIb/IIIa activation and subsequent RhoA/ROCK signaling via GPIIb/IIIa 'outside-in' signaling showed that platelets from females produce 3-fold greater levels of phosphorylated protein kinase C (PKC) substrates. There was a 2.5-fold greater level of activated RhoA, and platelet sub-fractionation analysis demonstrated 2.7-fold more RhoA in the membrane fraction of female vs. male platelets. Similarly, there was a 2.8-fold increase in levels of phosphorylated myosin light chain (MLC) in platelets from females vs. males. The increased signaling activity in platelets from females mirrors their greater sensitivity to agonists. These findings further our understanding of the molecular differences between platelets from males and females.


Assuntos
Plaquetas/citologia , Agregação Plaquetária , Transdução de Sinais , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Adolescente , Adulto , Idoso , Plaquetas/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Selectina-P/metabolismo , Fosforilação , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Proteína Quinase C/metabolismo , Caracteres Sexuais , Adulto Jovem
17.
Transfus Med Rev ; 30(2): 53-68, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26962008

RESUMO

Testing donations for pathogens and deferring selected blood donors have reduced the risk of transmission of known pathogens by transfusion to extremely low levels in most developed countries. Protecting the blood supply from emerging infectious threats remains a serious concern in the transfusion medicine community. Transfusion services can employ indirect measures such as surveillance, hemovigilance, and donor questioning (defense), protein-, or nucleic acid based direct testing (detection), or pathogen inactivation of blood products (destruction) as strategies to mitigate the risk of transmission-transmitted infection. In the North American context, emerging threats currently include dengue, chikungunya, and hepatitis E viruses, and Babesia protozoan parasites. The 2003 SARS and 2014 Ebola outbreaks illustrate the potential of epidemics unlikely to be transmitted by blood transfusion but disruptive to blood systems. Donor-free blood products such as ex vivo generated red blood cells offer a theoretical way to avoid transmission-transmitted infection risk, although biological, engineering, and manufacturing challenges must be overcome before this approach becomes practical. Similarly, next generation sequencing of all nucleic acid in a blood sample is currently possible but impractical for generalized screening. Pathogen inactivation systems are in use in different jurisdictions around the world, and are starting to gain regulatory approval in North America. Cost concerns make it likely that pathogen inactivation will be contemplated by blood operators through the lens of health economics and risk-based decision making, rather than in zero-risk paradigms previously embraced for transfusable products. Defense of the blood supply from infectious disease risk will continue to require innovative combinations of surveillance, detection, and pathogen avoidance or inactivation.


Assuntos
Segurança do Sangue , Patógenos Transmitidos pelo Sangue , Segurança do Sangue/economia , Segurança do Sangue/métodos , Segurança do Sangue/normas , Patógenos Transmitidos pelo Sangue/isolamento & purificação , Canadá , Técnicas de Cultura de Células , Células Cultivadas , Controle de Doenças Transmissíveis , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/prevenção & controle , Doenças Transmissíveis Emergentes/transmissão , Surtos de Doenças , Transmissão de Doença Infecciosa/prevenção & controle , Seleção do Doador/legislação & jurisprudência , Seleção do Doador/métodos , Seleção do Doador/organização & administração , Seleção do Doador/normas , Ebolavirus/genética , Ebolavirus/isolamento & purificação , Eritrócitos/citologia , Doença pelo Vírus Ebola/sangue , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/prevenção & controle , Doença pelo Vírus Ebola/transmissão , Humanos , Gestão de Riscos , Análise de Sequência/métodos , Reação Transfusional , Inativação de Vírus
18.
Pediatr Pulmonol ; 51(8): 820-4, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26969913

RESUMO

OBJECTIVE: B-type natriuretic peptide (BNP) has been shown to correlate with pulmonary hypertension (PH) in term neonates with persistent pulmonary hypertension of the newborn or congenital diaphragmatic hernia, and in very preterm infants with bronchopulmonary dysplasia. This study investigated the potential association of BNP and N-terminal-pro-BNP (NTproBNP) and PH within the first 72 hr of life in very preterm infants. METHODS: Preterm infants <32 weeks gestational age who received an echocardiogram within the first 72 hr of life were eligible. BNP and NTproBNP were sampled at the time of the echocardiogram. Right ventricular systolic pressure (RVSP) was calculated as a surrogate marker of PH. Simple and multiple linear regression analysis was performed to examine associations and potential confounding factors. RESULTS: Sixty-one infants were included with a median (IQR) birth weight of 983 g (826-1,167) and a median (IQR) gestational age of 27(2) weeks (26(2) -28(6) ). There was no difference between BNP or NTproBNP levels for infants with or without measurable RVSP. There was no significant correlation of BNP and RVSP in multiple linear regression analysis (regression coefficient -0.0035 (95%CI: -0.020 to 0.013), P = 0.67). Also, NTproBNP and RVSP were not significantly correlated in multiple linear regression analysis (regression coefficient 0.0071 (95%CI: -0.019 to 0.033), P = 0.58). CONCLUSION: B-type natriuretic peptides did not correlate with RVSP in the early postnatal period of very preterm infants. Pediatr Pulmonol. 2016;51:820-824. © 2016 Wiley Periodicals, Inc.


Assuntos
Hipertensão Pulmonar/sangue , Doenças do Prematuro/sangue , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Biomarcadores , Pressão Sanguínea/fisiologia , Ecocardiografia , Feminino , Idade Gestacional , Humanos , Lactente Extremamente Prematuro , Recém-Nascido , Masculino , Estudos Prospectivos , Sístole
19.
Transfus Med Rev ; 29(3): 181-94, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25862281

RESUMO

Plasma obtained via whole blood donation processing or via apheresis technology can either be transfused directly to patients or pooled and fractionated into plasma protein products that are concentrates of 1 or more purified plasma protein. The evidence base supporting clinical efficacy in most of the indications for which plasma is transfused is weak, whereas high-quality evidence supports the efficacy of plasma protein products in at least some of the clinical settings in which they are used. Transfusable plasma utilization remains composed in part of applications that fall outside of clinical practice guidelines. Plasma contains all of the soluble coagulation factors and is frequently transfused in efforts to restore or reinforce patient hemostasis. The biochemical complexities of coagulation have in recent years been rationalized in newer cell-based models that supplement the cascade hypothesis. Efforts to normalize widely used clinical hemostasis screening test values by plasma transfusion are thought to be misplaced, but superior rapid tests have been slow to emerge. The advent of non-vitamin K-dependent oral anticoagulants has brought new challenges to clinical laboratories in plasma testing and to clinicians needing to reverse non-vitamin K-dependent oral anticoagulants urgently. Current plasma-related controversies include prophylactic plasma transfusion before invasive procedures, plasma vs prothrombin complex concentrates for urgent warfarin reversal, and the utility of increased ratios of plasma to red blood cell units transfused in massive transfusion protocols. The first recombinant plasma protein products to reach the clinic were recombinant hemophilia treatment products, and these donor-free equivalents to factors VIII and IX are now being supplemented with novel products whose circulatory half-lives have been increased by chemical modification or genetic fusion. Achieving optimal plasma utilization is an ongoing challenge in the interconnected worlds of transfusable plasma, plasma protein products, and recombinant and engineered replacements.


Assuntos
Transfusão de Componentes Sanguíneos/métodos , Plasma , Preservação de Sangue/métodos , Canadá , Hemofilia A/terapia , Hemorragia/etiologia , Hemorragia/terapia , Hemostasia , Técnicas Hemostáticas , Humanos , Plasma/fisiologia
20.
Breast ; 11(5): 414-8, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14965705

RESUMO

BACKGROUND: The objective of this study was to review the need for radiotherapy or not in patients with occult primary breast cancer presenting with axillary metastases treated with breast conservation usually with no surgery to the breast. METHODS: From 1975 to 2001, 58 patients were treated with axillary lymphadenopathy from a cryptic primary breast carcinoma. After clinical and radiological assessment, 29 patients retained a diagnosis of occult primary breast carcinoma. Clinical and pathological data were collected retrospectively on the 29 patients and survival was calculated from the date of initial diagnosis using the Kaplan-Meier method. The median follow-up was 44 months. RESULTS: Median age at diagnosis was 57 years (range 28-81 years). Sixteen patients had radiotherapy to the ipsilateral breast. Eleven patients received no local therapy to the ipsilateral breast and two patients had quadrantectomies which were negative for malignancy. Locoregional relapse occurred in 12.5% of patients who had received radiotherapy and 69% of those who had not received any radiotherapy (P=0.02). Fifty-seven per cent of patients having a local relapse were salvaged with further surgery. The eventual breast conservation rate was 93%. Patients who received radiotherapy to the breast had significantly improved relapse-free survival (HR=0.31; P=0.04) and local relapse-free survival (HR=0.09; P=0.004). There were no significant differences in overall survival between those patients who had breast irradiation and those who did not (HR 0.91; 95% CI 0.18-4.5). CONCLUSION: Occult primary carcinoma with axillary metastases can be treated successfully with breast preservation but radiotherapy to the breast is necessary to minimize the risk of locoregional recurrence.

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