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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.
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
5.
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
6.
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
7.
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
8.
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
10.
Eur J Cancer ; 47(14): 2099-106, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21658935

RESUMO

AIM: To assess the role of ipsilateral breast radiotherapy (IBR) in women with occult primary breast cancer presenting with axillary metastases (OPBC). METHODS: Patients with axillary nodal metastases and histological diagnosis of breast cancer without palpable, mammographic or ultrasonographic evidence of a breast primary were identified from a prospectively maintained single institution database. Imaging, surgery, radiotherapy, recurrence and survival data were collected. Patients whose breast cancer primary was detected on MRI (but occult on clinical examination and other imaging) were excluded from the analyses of IBR and outcome, but were included in other exploratory analyses. RESULTS: Fifty-five patients were included between 1975 and 2009. Median follow up was 68 months. Twenty patients had breast magnetic resonance imaging (MRI) in addition to other imaging. A primary breast cancer was detected in 7 of these 20. 48/55 patients had no detectable breast primary. 35/48 patients (73%) were treated with radiotherapy to the conserved breast, and 13/48 (27%) with observation. Patients who had IBR had better 5 year local recurrence free survival (LRFS) (84% versus 34%, p<0.001), and relapse free survival (RFS) (64% versus 34%, p=0.05), but no difference in overall survival (OS) (84% versus 85%, p=0.2). There was no difference in 5 year LRFS (80% versus 90%: p=0.3) between patients who received radiation of 50 Gy in 25 fractions versus ≥60 Gy. CONCLUSION: Patients with OPBC should be managed with IBR and breast conservation, or mastectomy. Our data suggest it is not necessary to irradiate the breast to more than 50 Gy in 25 fractions.


Assuntos
Neoplasias da Mama/radioterapia , Recidiva Local de Neoplasia/diagnóstico , Neoplasias Primárias Desconhecidas/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/secundário , Quimioterapia Adjuvante , Terapia Combinada , Intervalo Livre de Doença , Relação Dose-Resposta à Radiação , Feminino , Seguimentos , Humanos , Metástase Linfática/patologia , Metástase Linfática/radioterapia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Neoplasias Primárias Desconhecidas/tratamento farmacológico , Neoplasias Primárias Desconhecidas/mortalidade , Neoplasias Primárias Desconhecidas/patologia , Dosagem Radioterapêutica , Resultado do Tratamento
11.
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
12.
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
13.
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
14.
Cancer ; 116(11 Suppl): 2815-20, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20503413

RESUMO

BACKGROUND: Treatments for inflammatory breast cancer (IBC) have changed over the last 15 to 20 years. The authors of this report undertook a retrospective review of patients who were treated at the Royal Marsden Hospital (RMH) to determine whether recurrence-free survival (RFS) and overall survival (OS) have improved as treatment regimens have altered. METHODS: Detailed clinical-pathologic data were collected on patients who were treated for primary IBC at RMH between 1990 and 2007. A Cox regression model was used to investigate the factors that influenced OS. RESULTS: The median OS was 3 years and 4 months, and the median RFS was 1 year and 10 months. RFS was better in patients who had received taxane-containing regimens; however, there was no OS benefit. A pathologic complete response (pCR) was observed in 13 of 89 patients (15%), and those who achieved a pCR had significantly better RFS but no improvement in OS. The type of chemotherapy did not affect the pCR rate. One hundred thirty of 155 patients received radiotherapy, and those who did not receive radiotherapy had significantly worse outcomes. A multivariate Cox regression analysis indicated that the date of diagnosis, estrogen receptor (ER) status, and the presence of metastatic disease at diagnosis were significant prognostic factors. Patients who were diagnosed during or after 2000 had a relative risk of mortality of 0.5 compared with patients who were diagnosed before 2000. ER-positive patients had a median OS of 4.5 years and a median of RFS of 2.6 years versus 2.9 years and 1.4 years, respectively, for ER-negative patients. Patients who had metastatic disease at presentation had an OS of 1.7 years versus 3.9 years for those without metastatic disease at presentation. CONCLUSIONS: Achieving a pCR improved RFS but had no impact on OS. Patients who had metastatic disease at the outset fared much worse, and positive ER status conferred a better outlook.


Assuntos
Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Hidrocarbonetos Aromáticos com Pontes/uso terapêutico , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Inflamação/terapia , Metástase Neoplásica , Prognóstico , Estudos Retrospectivos , Taxoides/uso terapêutico , Fatores de Tempo
15.
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
16.
J Proteomics ; 72(5): 838-52, 2009 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-19121650

RESUMO

Multiple reaction monitoring (MRM), commonly employed for the mass spectrometric detection of small molecules, is rapidly gaining ground in proteomics. Its high sensitivity and specificity makes this targeted approach particularly useful when sample throughput or proteome coverage limits global studies. Existing tools to design MRM assays rely exclusively on theoretical predictions, or combine them with previous observations on the same type of sample. The additional mass spectrometric experimentation this requires can pose significant demands on time and material. To overcome these challenges, a new MRM worksheet was introduced into The Global Proteome Machine database (GPMDB) that provided all of the information needed to design MRM transitions based solely on archived observations made by other researchers in previous experiments. This required replacing the precursor ion intensity by the number of peptide observations, which proved to be an adequate substitute if peptides did not occur in multiple forms. While the absence of collision energy information proved largely inconsequential, successful prediction of unique transitions depended on the type of fragment ion involved. The design of MRM assays for iTRAQ-labeled tryptic peptides obtained from human platelet proteins demonstrated the usefulness of the MRM worksheet also for quantitative applications. This workflow, which relies exclusively on experimental observations stored in data repositories, therefore represents an attractive alternative for the prediction of MRM transitions prior to experimental validation and optimization.


Assuntos
Proteômica/instrumentação , Proteômica/métodos , Plaquetas/metabolismo , Proteínas Sanguíneas/química , Biologia Computacional/métodos , Bases de Dados de Proteínas , Humanos , Íons , Espectrometria de Massas/métodos , Peptídeos/química , Proteínas/química , Proteoma
17.
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
18.
Breast Cancer Res Treat ; 110(3): 411-6, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17851753

RESUMO

PURPOSE: Ovarian failure and infertility following adjuvant chemotherapy for early breast cancer are major concerns for some young women. Techniques for oocyte harvesting are associated with delay in starting treatment, potentially undesirable estrogen stimulation and a relatively low success rate. We report an audit of our experience with the luteinising hormone-releasing hormone agonist, goserelin, to achieve transient ovarian suppression during chemotherapy as a means of preserving ovarian function. PATIENT AND METHODS: Pre-menopausal women were offered goserelin 3.6 mg by subcutaneous injection every 28 days during chemotherapy, starting 0-14 days prior to treatment. The primary end-point was recovery of menstruation. Serum luteinising hormone, follicle stimulating hormone and oestradiol were measured at recovery of menstruation or at first year follow-up if amenorrhoea persisted. Subsequent pregnancies were recorded. RESULTS: Fifty-one evaluable women were audited. Amenorrhoea occurred in all but one. All received combination anthracycline-containing chemotherapy regimens with a mean cumulative cyclophosphamide dose of 3.9 g/m(2). Forty-five (90%) recovered menstruation during the first year of follow-up; mean time to recovery 5 months. Eight pregnancies in 10 women attempting this so far. CONCLUSION: Using goserelin concurrently with chemotherapy is associated with a high rate of ovarian function preservation.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Gosserrelina/uso terapêutico , Ovário/efeitos dos fármacos , Pré-Menopausa , Adulto , Quimioterapia Adjuvante , Feminino , Fertilidade/efeitos dos fármacos , Humanos , Insuficiência Ovariana Primária/induzido quimicamente , Insuficiência Ovariana Primária/prevenção & controle
19.
J Clin Oncol ; 25(25): 3816-22, 2007 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-17679728

RESUMO

PURPOSE: Increased epidermal growth factor receptor (EGFR) expression may promote breast cancer resistance to endocrine therapy. We have therefore investigated whether neoadjuvant gefitinib, an EGFR inhibitor, might overcome biologic and clinical resistance to neoadjuvant anastrozole in a phase II placebo-controlled trial. PATIENTS AND METHODS: Postmenopausal women with stage I to IIIB hormone receptor-positive early breast cancer received anastrozole 1 mg daily for 16 weeks and were randomly assigned at a ratio of 2:5:5 to receive, in addition, gefitinib 250 mg/d orally for 16 weeks: placebo 1 tablet/d orally for 2 weeks and then gefitinib for 14 weeks or placebo for 16 weeks. The primary end point was biologic change in proliferation as measured by Ki67 at 2 and 16 weeks; the main secondary end point was overall objective response (OR). RESULTS: Two hundred six women were randomly assigned. Mean changes in Ki67 with anastrozole and gefitinib versus anastrozole alone were -77.4% and -83.6%, respectively, between baseline and 16 weeks (geometric mean ratio = 1.37; 95% CI, 0.79 to 2.39; P = .26), -80.1% and -71.3% between baseline and 2 weeks (geometric mean ratio = 0.70; 95% CI, 0.39 to 1.25; P = .22) and -19.3% and -43% (geometric mean ratio = 1.42; 95% CI, 0.86 to 2.35; P = .16) between 2 and 16 weeks. ORs in the combination and anastrozole alone groups were 48% and 61% (estimated difference = -13.1%; 95% CI, -27.3% to 1.2%), respectively, with a nonsignificant trend against the combination (P = .08) and 48% versus 72% (estimated difference = -24.1%; 95% CI, -45.3% to -2.9%) in the progesterone-receptor-positive subgroup, which was significant (P = .03) and consistent with Ki67 changes. Common treatment-related adverse events included diarrhea, rash, alopecia, dry skin, and nausea. There was no evidence of a pharmacokinetic interaction. CONCLUSION: Addition of gefitinib to neoadjuvant anastrozole had no additional clinical or biologic effect, failing to support our original hypothesis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Nitrilas/administração & dosagem , Quinazolinas/administração & dosagem , Triazóis/administração & dosagem , Idoso , Anastrozol , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/cirurgia , Receptores ErbB/metabolismo , Estradiol/metabolismo , Feminino , Gefitinibe , Humanos , Antígeno Ki-67/metabolismo , Mastectomia , Receptor ErbB-2/metabolismo , Receptores de Progesterona/metabolismo
20.
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
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