RESUMEN
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.
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Infecciones por VIH , Minorías Sexuales y de Género , Masculino , Humanos , Homosexualidad Masculina , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Canadá/epidemiología , Conducta Sexual , Donantes de SangreRESUMEN
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.
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Antraciclinas/uso terapéutico , Neoplasias de la Mama Masculina/tratamiento farmacológico , Neoplasias de la Mama/tratamiento farmacológico , Hidrocarburos Aromáticos con Puentes/uso terapéutico , Taxoides/uso terapéutico , Adulto , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Neoplasias de la Mama Masculina/patología , Neoplasias de la Mama Masculina/cirugía , Quimioterapia Adyuvante , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Análisis de Supervivencia , Factores de Tiempo , Resultado del Tratamiento , Reino UnidoRESUMEN
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.
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Displasia Broncopulmonar/sangre , Proteína 1 Similar a Quitinasa-3/sangre , Hipertensión Pulmonar/sangre , Recien Nacido Extremadamente Prematuro/sangre , Péptido Natriurético Encefálico/sangre , Troponina I/sangre , Biomarcadores/sangre , Displasia Broncopulmonar/complicaciones , Demografía , Femenino , Humanos , Hipertensión Pulmonar/complicaciones , Masculino , Ventilación Pulmonar , Factores de RiesgoRESUMEN
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.
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Seguridad de la Sangre , Patógenos Transmitidos por la Sangre , Seguridad de la Sangre/economía , Seguridad de la Sangre/métodos , Seguridad de la Sangre/normas , Patógenos Transmitidos por la Sangre/aislamiento & purificación , Canadá , Técnicas de Cultivo de Célula , Células Cultivadas , Control de Enfermedades Transmisibles , Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Transmisibles Emergentes/prevención & control , Enfermedades Transmisibles Emergentes/transmisión , Brotes de Enfermedades , Transmisión de Enfermedad Infecciosa/prevención & control , Selección de Donante/legislación & jurisprudencia , Selección de Donante/métodos , Selección de Donante/organización & administración , Selección de Donante/normas , Ebolavirus/genética , Ebolavirus/aislamiento & purificación , Eritrocitos/citología , Fiebre Hemorrágica Ebola/sangre , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/prevención & control , Fiebre Hemorrágica Ebola/transmisión , Humanos , Gestión de Riesgos , Análisis de Secuencia/métodos , Reacción a la Transfusión , Inactivación de VirusRESUMEN
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.
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Hipertensión Pulmonar/sangre , Enfermedades del Prematuro/sangre , Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Biomarcadores , Presión Sanguínea/fisiología , Ecocardiografía , Femenino , Edad Gestacional , Humanos , Recien Nacido Extremadamente Prematuro , Recién Nacido , Masculino , Estudios Prospectivos , SístoleRESUMEN
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.
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Plaquetas/citología , Agregación Plaquetaria , Transducción de Señal , Quinasas Asociadas a rho/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , Adolescente , Adulto , Anciano , Plaquetas/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Selectina-P/metabolismo , Fosforilación , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo , Proteína Quinasa C/metabolismo , Caracteres Sexuales , Adulto JovenRESUMEN
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.
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Transfusión de Componentes Sanguíneos/métodos , Plasma , Conservación de la Sangre/métodos , Canadá , Hemofilia A/terapia , Hemorragia/etiología , Hemorragia/terapia , Hemostasis , Técnicas Hemostáticas , Humanos , Plasma/fisiologíaRESUMEN
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.
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Plaquetas/inmunología , Complejo de la Endopetidasa Proteasomal/inmunología , Subunidades de Proteína/inmunología , Proteoma/inmunología , Plaquetas/química , Plaquetas/metabolismo , Línea Celular Tumoral , Minería de Datos , Expresión Génica , Células HEK293 , Antígenos de Histocompatibilidad Clase I/química , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase I/inmunología , Humanos , Inmunidad Innata , Anotación de Secuencia Molecular , Cultivo Primario de Células , Complejo de la Endopetidasa Proteasomal/química , Complejo de la Endopetidasa Proteasomal/genética , Subunidades de Proteína/química , Subunidades de Proteína/genética , Proteoma/química , Proteoma/genéticaRESUMEN
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.
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Neoplasias de la Mama/radioterapia , Recurrencia Local de Neoplasia/diagnóstico , Neoplasias Primarias Desconocidas/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Axila , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/secundario , Quimioterapia Adyuvante , Terapia Combinada , Supervivencia sin Enfermedad , Relación Dosis-Respuesta en la Radiación , Femenino , Estudios de Seguimiento , Humanos , Metástasis Linfática/patología , Metástasis Linfática/radioterapia , Persona de Mediana Edad , Recurrencia Local de Neoplasia/prevención & control , Neoplasias Primarias Desconocidas/tratamiento farmacológico , Neoplasias Primarias Desconocidas/mortalidad , Neoplasias Primarias Desconocidas/patología , Dosificación Radioterapéutica , Resultado del TratamientoRESUMEN
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.
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Homocisteína/metabolismo , Hiperhomocisteinemia/metabolismo , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo , Trombosis/metabolismo , Anticuerpos/metabolismo , Sitios de Unión de Anticuerpos/efectos de los fármacos , Plaquetas/metabolismo , Estudios de Casos y Controles , Femenino , Homocisteína/análogos & derivados , Homocisteína/farmacología , Humanos , Hiperhomocisteinemia/complicaciones , Hiperhomocisteinemia/fisiopatología , Integrinas/metabolismo , Masculino , Activación Plaquetaria/efectos de los fármacos , Agregación Plaquetaria/efectos de los fármacos , Unión Proteica/efectos de los fármacos , Factores de Riesgo , Compuestos de Sulfhidrilo/metabolismo , Trombosis/etiología , Trombosis/fisiopatologíaRESUMEN
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.
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Investigación Biomédica/tendencias , Espectrometría de Masas/tendencias , Proteómica/tendencias , HumanosRESUMEN
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.
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Antineoplásicos/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Inhibidores de la Ciclooxigenasa 2/administración & dosificación , Ciclooxigenasa 2/metabolismo , Pirazoles/administración & dosificación , Sulfonamidas/administración & dosificación , Anciano , Anciano de 80 o más Años , Apoptosis/efectos de los fármacos , Biopsia , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Celecoxib , Proliferación Celular/efectos de los fármacos , Quimioterapia Adyuvante , Esquema de Medicación , Femenino , Humanos , Antígeno Ki-67/metabolismo , Londres , Persona de Mediana Edad , Terapia Neoadyuvante , Estadificación de Neoplasias , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , Posmenopausia , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Factores de Tiempo , Resultado del TratamientoRESUMEN
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.
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Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Hidrocarburos Aromáticos con Puentes/uso terapéutico , Terapia Combinada , Supervivencia sin Enfermedad , Femenino , Humanos , Inflamación/terapia , Metástasis de la Neoplasia , Pronóstico , Estudios Retrospectivos , Taxoides/uso terapéutico , Factores de TiempoRESUMEN
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.
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Plaquetas/metabolismo , Conservación de la Sangre/efectos adversos , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal , Proteínas de Unión al GTP rap1/metabolismo , Plaquetas/efectos de los fármacos , Western Blotting , Cromonas/farmacología , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Microscopía Fluorescente , Morfolinas/farmacología , Inhibidores de las Quinasa Fosfoinosítidos-3 , Transducción de Señal/efectos de los fármacosRESUMEN
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.
Asunto(s)
Plaquetas/metabolismo , Proteínas Sanguíneas/análisis , Espectrometría de Masas/métodos , Óxidos de Nitrógeno/metabolismo , Procesamiento Proteico-Postraduccional , Secuencia de Aminoácidos , Proteínas Sanguíneas/química , Cisteína/metabolismo , Gliceraldehído-3-Fosfato Deshidrogenasa (Fosforilante)/metabolismo , Humanos , Cinética , Datos de Secuencia Molecular , Péptidos/química , Proteoma/análisis , Proteómica , Reproducibilidad de los Resultados , Compuestos de Sulfonio/metabolismo , Espectrometría de Masas en TándemRESUMEN
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.
Asunto(s)
Proteómica/instrumentación , Proteómica/métodos , Plaquetas/metabolismo , Proteínas Sanguíneas/química , Biología Computacional/métodos , Bases de Datos de Proteínas , Humanos , Iones , Espectrometría de Masas/métodos , Péptidos/química , Proteínas/química , ProteomaRESUMEN
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.
Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Goserelina/uso terapéutico , Ovario/efectos de los fármacos , Premenopausia , Adulto , Quimioterapia Adyuvante , Femenino , Fertilidad/efectos de los fármacos , Humanos , Insuficiencia Ovárica Primaria/inducido químicamente , Insuficiencia Ovárica Primaria/prevención & controlRESUMEN
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.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Nitrilos/administración & dosificación , Quinazolinas/administración & dosificación , Triazoles/administración & dosificación , Anciano , Anastrozol , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/cirugía , Receptores ErbB/metabolismo , Estradiol/metabolismo , Femenino , Gefitinib , Humanos , Antígeno Ki-67/metabolismo , Mastectomía , Receptor ErbB-2/metabolismo , Receptores de Progesterona/metabolismoRESUMEN
The exact mechanisms regulating conformational changes in the platelet-specific integrin alphaIIbbeta3 are not fully understood. However, a role exists for thiol/disulfide exchange in integrin conformational changes leading to altered disulfide bonding patterns, via its endogenous thiol isomerase activity. Nitric oxide (NO) accelerates this intrinsic enzymatic activity and, in doing so, reverses the activational state of the integrin on the platelet surface toward a more unactivated one. We propose that it is an S-nitrosylation-induced "shuffling" of thiol/disulfide exchange that regulates this reversal of the activated state of the integrin. In this study, we use Raman spectroscopy to explore S-nitrosylation of purified alphaIIbbeta3. Using S-nitrosoglutathione (GSNO) as a model system, we identify Raman markers which show a direct interaction between NO and the thiol groups of the integrin and reveal many of the structural changes that occur in alphaIIbbeta3 in the course of not only its activation but also its deactivation. Key conformational changes are detected within the integrin when treated with manganese (Mn2+), occurring mainly in the cysteine and disulfide regions of the protein, confirming the importance of thiol/disulfide exchange in integrin activation. These changes are subsequently shown to be reversed in the presence of NO.