Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 73
Filtrar
Más filtros

Intervalo de año de publicación
1.
Int J Cancer ; 153(9): 1671-1683, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37497753

RESUMEN

Breast cancer is composed of metabolically coupled cellular compartments with upregulation of TP53 Induced Glycolysis and Apoptosis Regulator (TIGAR) in carcinoma cells and loss of caveolin 1 (CAV1) with upregulation of monocarboxylate transporter 4 (MCT4) in fibroblasts. The mechanisms that drive metabolic coupling are poorly characterized. The effects of TIGAR on fibroblast CAV1 and MCT4 expression and breast cancer aggressiveness was studied using coculture and conditioned media systems and in-vivo. Also, the role of cytokines in promoting tumor metabolic coupling via MCT4 on cancer aggressiveness was studied. TIGAR downregulation in breast carcinoma cells reduces tumor growth. TIGAR overexpression in carcinoma cells drives MCT4 expression and NFkB activation in fibroblasts. IL6 and TGFB drive TIGAR upregulation in carcinoma cells, reduce CAV1 and increase MCT4 expression in fibroblasts. Tumor growth is abrogated in the presence of MCT4 knockout fibroblasts and environment. We discovered coregulation of c-MYC and TIGAR in carcinoma cells driven by lactate. Metabolic coupling primes the tumor microenvironment allowing for production, uptake and utilization of lactate. In sum, aggressive breast cancer is dependent on metabolic coupling.


Asunto(s)
Neoplasias de la Mama , Carcinoma , Humanos , Femenino , Neoplasias de la Mama/patología , Proteínas Reguladoras de la Apoptosis/metabolismo , Glucólisis , Ácido Láctico/metabolismo , FN-kappa B/metabolismo , Apoptosis , Línea Celular Tumoral , Microambiente Tumoral , Proteína p53 Supresora de Tumor/metabolismo
2.
J Biol Chem ; 291(51): 26291-26303, 2016 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-27803158

RESUMEN

A subgroup of breast cancers has several metabolic compartments. The mechanisms by which metabolic compartmentalization develop in tumors are poorly characterized. TP53 inducible glycolysis and apoptosis regulator (TIGAR) is a bisphosphatase that reduces glycolysis and is highly expressed in carcinoma cells in the majority of human breast cancers. Hence we set out to determine the effects of TIGAR expression on breast carcinoma and fibroblast glycolytic phenotype and tumor growth. The overexpression of this bisphosphatase in carcinoma cells induces expression of enzymes and transporters involved in the catabolism of lactate and glutamine. Carcinoma cells overexpressing TIGAR have higher oxygen consumption rates and ATP levels when exposed to glutamine, lactate, or the combination of glutamine and lactate. Coculture of TIGAR overexpressing carcinoma cells and fibroblasts compared with control cocultures induce more pronounced glycolytic differences between carcinoma and fibroblast cells. Carcinoma cells overexpressing TIGAR have reduced glucose uptake and lactate production. Conversely, fibroblasts in coculture with TIGAR overexpressing carcinoma cells induce HIF (hypoxia-inducible factor) activation with increased glucose uptake, increased 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase-3 (PFKFB3), and lactate dehydrogenase-A expression. We also studied the effect of this enzyme on tumor growth. TIGAR overexpression in carcinoma cells increases tumor growth in vivo with increased proliferation rates. However, a catalytically inactive variant of TIGAR did not induce tumor growth. Therefore, TIGAR expression in breast carcinoma cells promotes metabolic compartmentalization and tumor growth with a mitochondrial metabolic phenotype with lactate and glutamine catabolism. Targeting TIGAR warrants consideration as a potential therapy for breast cancer.


Asunto(s)
Neoplasias de la Mama/metabolismo , Ácido Glutámico/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Ácido Láctico/metabolismo , Apoptosis/genética , Proteínas Reguladoras de la Apoptosis , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Técnicas de Cocultivo , Femenino , Fibroblastos/metabolismo , Fibroblastos/patología , Ácido Glutámico/genética , Glucólisis/genética , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Isoenzimas/genética , Isoenzimas/metabolismo , L-Lactato Deshidrogenasa/genética , L-Lactato Deshidrogenasa/metabolismo , Lactato Deshidrogenasa 5 , Células MCF-7 , Fosfofructoquinasa-2/genética , Fosfofructoquinasa-2/metabolismo , Monoéster Fosfórico Hidrolasas , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
3.
Health Econ ; 24(4): 481-90, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24590819

RESUMEN

The Institute for Quality and Efficiency in Health Care (IQWiG) developed-in a consultation process with an international expert panel-the efficiency frontier (EF) approach to satisfy a range of legal requirements for economic evaluation in Germany's statutory health insurance system. The EF approach is distinctly different from other health economic approaches. Here, we evaluate established tools for assessing and communicating parameter uncertainty in terms of their applicability to the EF approach. Among these are tools that perform the following: (i) graphically display overall uncertainty within the IQWiG EF (scatter plots, confidence bands, and contour plots) and (ii) communicate the uncertainty around the reimbursable price. We found that, within the EF approach, most established plots were not always easy to interpret. Hence, we propose the use of price reimbursement acceptability curves-a modification of the well-known cost-effectiveness acceptability curves. Furthermore, it emerges that the net monetary benefit allows an intuitive interpretation of parameter uncertainty within the EF approach. This research closes a gap for handling uncertainty in the economic evaluation approach of the IQWiG methods when using the EF. However, the precise consequences of uncertainty when determining prices are yet to be defined.


Asunto(s)
Personal Administrativo , Seguro de Salud/organización & administración , Comunicación , Análisis Costo-Beneficio , Economía Médica/estadística & datos numéricos , Alemania , Costos de la Atención en Salud/estadística & datos numéricos , Política de Salud/economía , Humanos , Seguro de Salud/economía , Seguro de Salud/legislación & jurisprudencia , Seguro de Salud/estadística & datos numéricos , Modelos Teóricos , Incertidumbre
4.
Hemoglobin ; 38(6): 385-9, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25405915

RESUMEN

Previous studies have suggested that erythropoietin (Epo) levels may be inappropriately low in patients with sickle cell disease compared to the extent of the related anemia they demonstrate. Here, we evaluate Epo level vs. renal function, oxygenation, and markers of inflammation for patients treated for sickle cell disease at our institution. Blood was drawn from 54 patients with sickle cell disease during routine visits to the outpatient hematology office and analyzed for hemoglobin (Hb) level, Epo, markers of inflammation, oxygenation, and renal function. Erythropoietin levels were lower than expected for patients with sickle cell disease, compared to the degree of anemia demonstrated in these patients. In addition, a correlation between Hb level and Epo was not consistently observed. Higher Epo levels were seen in patients receiving hydroxyurea (HU), but no correlation with oxygenation, hemolysis, renal function, or inflammation was observed.


Asunto(s)
Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/tratamiento farmacológico , Antidrepanocíticos/administración & dosificación , Eritropoyetina/sangre , Hidroxiurea/administración & dosificación , Adulto , Anciano , Anemia de Células Falciformes/fisiopatología , Antidrepanocíticos/efectos adversos , Biomarcadores/sangre , Femenino , Hemoglobinas/metabolismo , Hemólisis , Humanos , Hidroxiurea/efectos adversos , Inflamación , Pruebas de Función Renal , Masculino , Persona de Mediana Edad
5.
Cell Stress ; 8: 1-20, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38476765

RESUMEN

Mesenchymal-epithelial plasticity driving cancer progression in cancer-associated fibroblasts (CAFs) is undetermined. This work identifies a subgroup of CAFs in human breast cancer exhibiting mesenchymal-to-epithelial transition (MET) or epithelial-like profile with high miR-200c expression. MiR-200c overexpression in fibroblasts is sufficient to drive breast cancer aggressiveness. Oxidative stress in the tumor microenvironment induces miR-200c by DNA demethylation. Proteomics, RNA-seq and functional analyses reveal that miR-200c is a novel positive regulator of NFκB-HIF signaling via COMMD1 downregulation and stimulates pro-tumorigenic inflammation and glycolysis. Reprogramming fibroblasts toward MET via miR-200c reduces stemness and induces a senescent phenotype. This pro-tumorigenic profile in CAFs fosters carcinoma cell resistance to apoptosis, proliferation and immunosuppression, leading to primary tumor growth, metastases, and resistance to immuno-chemotherapy. Conversely, miR-200c inhibition in fibroblasts restrains tumor growth with abated oxidative stress and an anti-tumorigenic immune environment. This work determines the mechanisms by which MET in CAFs via miR-200c transcriptional enrichment with DNA demethylation triggered by oxidative stress promotes cancer progression. CAFs undergoing MET trans-differentiation and senescence coordinate heterotypic signaling that may be targeted as an anti-cancer strategy.

6.
Value Health ; 13(8): 1056-60, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20825626

RESUMEN

OBJECTIVES: To argue that discrete event simulation should be preferred to cohort Markov models for economic evaluations in health care. METHODS: The basis for the modeling techniques is reviewed. For many health-care decisions, existing data are insufficient to fully inform them, necessitating the use of modeling to estimate the consequences that are relevant to decision-makers. These models must reflect what is known about the problem at a level of detail sufficient to inform the questions. Oversimplification will result in estimates that are not only inaccurate, but potentially misleading. RESULTS: Markov cohort models, though currently popular, have so many limitations and inherent assumptions that they are inadequate to inform most health-care decisions. An event-based individual simulation offers an alternative much better suited to the problem. A properly designed discrete event simulation provides more accurate, relevant estimates without being computationally prohibitive. It does require more data and may be a challenge to convey transparently, but these are necessary trade-offs to provide meaningful and valid results. CONCLUSION: In our opinion, discrete event simulation should be the preferred technique for health economic evaluations today.


Asunto(s)
Técnicas de Apoyo para la Decisión , Costos de la Atención en Salud , Modelos Estadísticos , Análisis Costo-Beneficio/métodos , Política de Salud/economía , Humanos , Cadenas de Markov , Modelos Económicos
7.
Am J Cardiovasc Drugs ; 10(1): 55-63, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20104935

RESUMEN

BACKGROUND: The EPHESUS (Eplerenone Post-Acute Myocardial Infarction Heart Failure and Survival Study) showed that the use of aldosterone blockade with eplerenone decreased mortality in patients with heart failure after acute myocardial infarction, and a subsequent analysis showed eplerenone to be highly cost effective in this population. OBJECTIVE: To assess the cost effectiveness of eplerenone in an EPHESUS subgroup population who were taking both ACE inhibitors and beta-blockers (beta-adrenoceptor antagonists) at baseline. In the EPHESUS, a total of 6632 patients were randomized to receive eplerenone 25-50 mg/day (n = 3319) or placebo (n = 3313) concurrently with standard therapy and were followed for up to 2.5 years. Of these, 4265 (64.3%) patients (eplerenone: n = 2113; placebo: n = 2152) were taking both ACE inhibitors and beta-blockers at baseline. METHODS AND MAIN OUTCOME MEASURES: Resource use after the initial hospitalization included additional hospitalizations, outpatient services, emergency room visits, and medications. Eplerenone was priced at an average wholesale price of $US3.60 per day (year 2004 value). Bootstrap methods were used to estimate the fraction of the joint distribution of the cost and effectiveness. A net-benefit regression model was used to derive the propensity score-adjusted cost-effectiveness curve. The incremental cost effectiveness of eplerenone in cost per life-year gained (LYG) and cost per quality-adjusted life-year (QALY) gained beyond the trial period was estimated using data from the Framingham Heart Study, the Saskatchewan Health database, and the Worcester Heart Attack Registry. Both costs and effectiveness were discounted at 3%. Although not all resource use could be accounted for, the overall perspective was societal. RESULTS: As in the overall EPHESUS population, the total direct treatment costs were higher in the eplerenone arm than the placebo arm for patients who were taking both ACE inhibitors and beta-blockers ($US14,563 vs $US12,850, difference = $US1713; 95% CI 721, 2684). The number of LYGs with eplerenone compared with placebo was 0.1665 based on the Framingham data, 0.0979 using the Saskatchewan data, and 0.2172 using the Worcester data. The incremental cost-effectiveness ratio (ICER) was $US10,288/LYG with the Framingham data, $US17,506/LYG with the Saskatchewan data, and $US7888/LYG with the Worcester data (99% <$US50,000/LYG for all three sources). The ICERs were systematically higher when calculated as the cost per QALY gained ($US14,926, $US25,447, and $US11,393, respectively) as the utilities were below 1 with no difference between the treatment arms. CONCLUSION: As for the overall EPHESUS population, aldosterone blockade with eplerenone is effective in reducing mortality and is cost effective in increasing years of life for the EPHESUS subgroup of patients who were taking both ACE inhibitors and beta-blockers.


Asunto(s)
Insuficiencia Cardíaca/tratamiento farmacológico , Antagonistas de Receptores de Mineralocorticoides/economía , Infarto del Miocardio/complicaciones , Espironolactona/análogos & derivados , Antagonistas Adrenérgicos beta/uso terapéutico , Anciano , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Análisis Costo-Beneficio , Relación Dosis-Respuesta a Droga , Quimioterapia Combinada , Eplerenona , Femenino , Estudios de Seguimiento , Costos de la Atención en Salud , Insuficiencia Cardíaca/economía , Insuficiencia Cardíaca/etiología , Humanos , Masculino , Persona de Mediana Edad , Antagonistas de Receptores de Mineralocorticoides/uso terapéutico , Infarto del Miocardio/economía , Años de Vida Ajustados por Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Análisis de Regresión , Espironolactona/economía , Espironolactona/uso terapéutico
8.
Hum Vaccin ; 6(11): 876-80, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20980794

RESUMEN

Pertussis remains endemic across the world, with an estimated 279,000 deaths in 2002, the majority in infants under 1 year of age. Worldwide epidemiologic data indicates increasing infection rates in older children and adults, which act as a source of infection to young infants. The Global Pertussis Initiative (GPI) is an expert scientific forum, which has published consensus recommendations for the monitoring, prevention, and treatment of the disease. This paper reports the proceedings of a regional meeting, held in Costa Rica in December 2008. The meeting gathered information on regional epidemiological, diagnostic capabilities and the ability to introduce GPI recommended vaccine strategies in Latin America. The capacity of Latin American countries to conduct vaccination programs is high and there is considerable government support. Whole-cell pertussis vaccines are used across Latin America, which appear to be quite effective. A 4-dose schedule is typically used (2, 4, 6, and 18 months), and a booster given at 4 to 6 years of age, with coverage often above 90%, but with regions of low coverage due to political and geographical difficulties. Adequate surveillance is lacking in many countries, giving insufficient data to guide vaccination policy. Improvements are being made, with countries such as Costa Rica, Panama, and Argentina introducing polymerase chain reaction (PCR) diagnosis. Those countries that do not currently use a preschool booster should launch one. Implementing vaccination programs in adolescents and/or adults to reduce exposure to infants would be beneficial and possible in most countries, given their current infrastructure.


Asunto(s)
Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Transmisibles Emergentes/prevención & control , Vacuna contra la Tos Ferina/inmunología , Tos Ferina/epidemiología , Tos Ferina/prevención & control , Humanos , Inmunización Secundaria/métodos , América Latina/epidemiología , Vacuna contra la Tos Ferina/administración & dosificación , Vigilancia de la Población , Vacunación/métodos
9.
Mol Cell Biol ; 26(6): 2019-28, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16507982

RESUMEN

Adaptation to hypoxic microenvironment is critical for tumor survival and metastatic spread. Hypoxia-inducible factor 1alpha (HIF-1alpha) plays a key role in this adaptation by stimulating the production of proangiogenic factors and inducing enzymes necessary for anaerobic metabolism. Histone deacetylase inhibitors (HDACIs) produce a marked inhibition of HIF-1alpha expression and are currently in clinical trials partly based on their potent antiangiogenic effects. Although it has been postulated that HDACIs affect HIF-1alpha expression by enhancing its interactions with VHL (von Hippel Lindau), thus promoting its ubiquitination and degradation, the actual mechanisms by which HDACIs decrease HIF-1alpha levels are not clear. Here, we present data indicating that HDACIs induce the proteasomal degradation of HIF-1alpha by a mechanism that is independent of VHL and p53 and does not require the ubiquitin system. This degradation pathway involves the enhanced interaction of HIF-1alpha with HSP70 and is secondary to a disruption of the HSP70/HSP90 axis function that appears mediated by the activity of HDAC-6.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Inhibidores de Histona Desacetilasas , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismo , Hipoxia de la Célula , Proteínas HSP70 de Choque Térmico/efectos de los fármacos , Proteínas HSP70 de Choque Térmico/metabolismo , Histona Desacetilasa 6 , Histona Desacetilasas/metabolismo , Humanos , Ácidos Hidroxámicos/farmacología , Subunidad alfa del Factor 1 Inducible por Hipoxia/efectos de los fármacos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Estructura Terciaria de Proteína , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/efectos de los fármacos , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Ubiquitina/metabolismo , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/efectos de los fármacos , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/genética
10.
Int J MS Care ; 21(3): 129-134, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31191178

RESUMEN

BACKGROUND: Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune disease characterized by unpredictable attacks of the optic nerves and spinal cord that cause neurologic deficits, including weakness, numbness, bowel/bladder dysfunction, and pain and reduced vision and can ultimately lead to blindness and paralysis. We assessed the effects of NMOSD on quality of life. METHODS: Adult patients with NMOSD treated at a US academic neurology clinic completed the EQ-5D and several other measures of functional status and quality of life. The EQ-5D scores and correlations across measures were evaluated, and scores were compared with those of patients with multiple sclerosis and US norms. RESULTS: Twenty-one patients (90% women; mean age, 42.8 years; mean disease duration, 8.2 years) were included. The mean EQ-5D score was 0.74. Most patients reported at least some problems with mobility, pain/discomfort, usual activities, and/or anxiety/depression. Greater proportions of patients reported moderate or severe problems with mobility and pain/discomfort than they did with self-care, usual activities, or anxiety/depression. In a multivariate model, only the Brief Pain Inventory was a significant independent predictor of overall EQ-5D score. CONCLUSIONS: Neuromyelitis optica spectrum disorder has a substantial effect on multiple domains of quality of life. Pain seems to be among the primary drivers of the EQ-5D scores in NMOSD.

11.
Spine J ; 8(1): 8-20, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18164449

RESUMEN

BACKGROUND CONTEXT: The economic burden of low back pain (LBP) is very large and appears to be growing. It is not possible to impact this burden without understanding the strengths and weaknesses of the research on which these costs are calculated. PURPOSE: To conduct a systematic review of LBP cost of illness studies in the United States and internationally. STUDY DESIGN/SETTING: Systematic review of the literature. METHODS: Medline was searched to uncover studies about the direct or indirect costs of LBP published in English from 1997 to 2007. Data extracted for each eligible study included study design, population, definition of LBP, methods of estimating costs, year of data, and estimates of direct, indirect, or total costs. Results were synthesized descriptively. RESULTS: The search yielded 147 studies, of which 21 were deemed relevant; 4 other studies and 2 additional abstracts were found by searching reference lists, bringing the total to 27 relevant studies. The studies reported on data from Australia, Belgium, Japan, Korea, the Netherlands, Sweden, the UK, and the United States. Nine studies estimated direct costs only, nine indirect costs only, and nine both direct and indirect costs, from a societal (n=18) or private insurer (n=9) perspective. Methodology used to derive both direct and indirect cost estimates differed markedly among the studies. Among studies providing a breakdown on direct costs, the largest proportion of direct medical costs for LBP was spent on physical therapy (17%) and inpatient services (17%), followed by pharmacy (13%) and primary care (13%). Among studies providing estimates of total costs, indirect costs resulting from lost work productivity represented a majority of overall costs associated with LBP. Three studies reported that estimates with the friction period approach were 56% lower than with the human capital approach. CONCLUSIONS: Several studies have attempted to estimate the direct, indirect, or total costs associated with LBP in various countries using heterogeneous methodology. Estimates of the economic costs in different countries vary greatly depending on study methodology but by any standards must be considered a substantial burden on society. This review did not identify any studies estimating the total costs of LBP in the United States from a societal perspective. Such studies may be helpful in determining appropriate allocation of health-care resources devoted to this condition.


Asunto(s)
Costo de Enfermedad , Gastos en Salud/tendencias , Dolor de la Región Lumbar/economía , Dolor de la Región Lumbar/terapia , Salud Global , Servicios de Salud/economía , Servicios de Salud/estadística & datos numéricos , Humanos , Estados Unidos
13.
Gac Sanit ; 22(2): 151-61, 2008.
Artículo en Español | MEDLINE | ID: mdl-18420015

RESUMEN

The use of mathematical models to assess therapeutic alternatives is increasing in the economic evaluation of health technologies and services and these models are becoming an increasingly important aid to decision making in health care. Until now, 2 types of model have been used, depending to some extent on the disease to be studied: decision trees have been used for acute diseases and Markov models in chronic or recurrent diseases. However, both models present major limitations when addressing complex processes or diseases. Consequently, interest in, and the use of, discrete-event simulation is growing. The present article aims to describe the main characteristics of discrete-event simulation, the state of the art in this field, and the advantages of these models with respect to other kinds of models in health economics, especially in the evaluation of health technologies and product assessment.


Asunto(s)
Tecnología Biomédica/economía , Simulación por Computador , Modelos Económicos , Evaluación de la Tecnología Biomédica/economía , Análisis Costo-Beneficio , Árboles de Decisión , Cadenas de Markov , Ciencia del Laboratorio Clínico/clasificación , Programas Informáticos
14.
Trials ; 19(1): 404, 2018 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-30055634

RESUMEN

BACKGROUND: The "Age of Blood in Children in Pediatric Intensive Care Unit" (ABC PICU) study is a randomized controlled trial (RCT) that aims to determine if red blood cell (RBC) unit storage age affects outcomes in critically ill children. While RBCs can be stored for up to 42 days in additive solutions, their efficacy and safety after long-term storage have been challenged. Preclinical and clinical observational evidence suggests loss of efficacy and lack of safety of older RBC units, especially in more vulnerable populations such as critically ill children. Because there is a belief that shorter storage will improve outcomes, some physicians and institutions systematically transfuse fresh RBCs to children. Conversely, the standard practice of blood banks is to deliver the oldest available RBC unit (first-in, first-out policy) in order to decrease wastage. METHODS/DESIGN: The ABC PICU study, is a double-blind superiority trial comparing the development of "New or Progressive Multiple Organ Dysfunction Syndrome" (NPMODS) in 1538 critically ill children randomized to either transfusion with RBCs stored for ≤ 7 days or to standard-issue RBCs (oldest in inventory). Patients are being recruited from 52 centers in the US, Canada, France, Italy, and Israel. DISCUSSION: The ABC PICU study should have significant implications for blood procurement services. A relative risk reduction of 33% is postulated in the short-storage arm. If a difference is found, this will indicate that fresher RBCs do improve outcomes in the pediatric intensive care unit population and would justify that use in critically ill children. If no difference is found, this will reassure clinicians and transfusion medicine specialists regarding the safety of the current system of allocating the oldest RBC unit in inventory and will discourage clinicians from preferentially requesting fresher blood for critically ill children. TRIAL REGISTRATION: ClinicalTrials.gov, ID: NCT01977547 . Registered on 6 November 2013.


Asunto(s)
Conservación de la Sangre/métodos , Transfusión de Eritrocitos/efectos adversos , Unidades de Cuidado Intensivo Pediátrico , Insuficiencia Multiorgánica/etiología , Adolescente , Conservación de la Sangre/efectos adversos , Conservación de la Sangre/mortalidad , Canadá , Niño , Preescolar , Enfermedad Crítica , Método Doble Ciego , Transfusión de Eritrocitos/mortalidad , Europa (Continente) , Femenino , Mortalidad Hospitalaria , Humanos , Lactante , Recién Nacido , Israel , Masculino , Estudios Multicéntricos como Asunto , Insuficiencia Multiorgánica/diagnóstico , Insuficiencia Multiorgánica/mortalidad , Insuficiencia Multiorgánica/prevención & control , Ensayos Clínicos Controlados Aleatorios como Asunto , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos
16.
Mol Cell Biol ; 22(9): 2984-92, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-11940656

RESUMEN

Hypoxia-inducible factor 1 complex (HIF-1) plays a pivotal role in oxygen homeostasis and adaptation to hypoxia. Its function is controlled by both the protein stability and the transactivation activity of its alpha subunit, HIF-1 alpha. Hydroxylation of at least two prolyl residues in the oxygen-dependent degradation domain of HIF-1 alpha regulates its interaction with the von Hippel-Lindau protein (VHL) that targets HIF-1 alpha for ubiquitination and proteasomal degradation. Several prolyl hydroxylases have been found to specifically hydroxylate HIF-1 alpha. In this report, we investigated possible roles of VHL and hydroxylases in the regulation of the transactivation activity of the C-terminal activating domain (CAD) of HIF-1 alpha. We demonstrate that regulation of the transactivation activity of HIF-1 alpha CAD also involves hydroxylase activity but does not require functional VHL. In addition, stimulation of the CAD activity by a hydroxylase inhibitor, hypoxia, and desferrioxamine was severely blocked by the adenoviral oncoprotein E1A but not by an E1A mutant defective in targeting p300/CBP. We further demonstrate that a hydroxylase inhibitor, hypoxia, and desferrioxamine promote the functional and physical interaction between HIF-1 alpha CAD and p300/CBP in vivo. Taken together, our data provide evidence that hypoxia-regulated stabilization and transcriptional stimulation of HIF-1 alpha function are regulated through partially overlapping but distinguishable pathways.


Asunto(s)
Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , Ligasas/fisiología , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Transactivadores/metabolismo , Factores de Transcripción , Activación Transcripcional , Proteínas Supresoras de Tumor , Ubiquitina-Proteína Ligasas , Proteínas E1A de Adenovirus/metabolismo , Aspartato Carbamoiltransferasa/metabolismo , Western Blotting , Carbamoil-Fosfato Sintasa (Glutamina-Hidrolizante)/metabolismo , Línea Celular , Deferoxamina/farmacología , Dihidroorotasa/metabolismo , Células HeLa , Humanos , Hidroxilación , Hipoxia/metabolismo , Factor 1 Inducible por Hipoxia , Subunidad alfa del Factor 1 Inducible por Hipoxia , Oxigenasas de Función Mixta/antagonistas & inhibidores , Complejos Multienzimáticos/metabolismo , Unión Proteica , Isoformas de Proteínas/metabolismo , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau
17.
Pharmacoeconomics ; 25(12): 997-1006, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18047386

RESUMEN

The National Institute for Health and Clinical Excellence (NICE) recently issued updated guidance on the use of cholinesterase inhibitors in the treatment of Alzheimer's disease. NICE initially recommended that cholinesterase inhibitors no longer be used, but final guidance restricted treatment to patients with disease of a moderately severe stage. This decision was based largely on results from a heavily criticised economic evaluation that used an adaptation of the Assessment of Health Economics in Alzheimer's Disease (AHEAD) model. As the developers of the AHEAD model, we examined the appropriateness of NICE's economic analyses and presentation of results. We attempted to replicate NICE's results by modifying the original AHEAD model. Sensitivity analyses were then run using the modified AHEAD model to evaluate the extent of uncertainty in predictions. The AHEAD(NICE) analyses resulted in an incremental cost-effectiveness ratio for galantamine of 82,000 pound per QALY gained (year 2003 values) from the perspective of the UK NHS and Personal Social Services. This was later revised to 46,000 pound per QALY, compared with < 9000 pound per discounted QALY gained (year 2001 values) in the original AHEAD model. Using our modified AHEAD with effectiveness estimates matching those of AHEAD(NICE), we show that NICE's choice and presentation of sensitivity analyses obscured the instability of their estimates. In the final NICE evaluation, the recommendation to delay treatment with cholinesterase inhibitors until patients have moderately severe disease was based on critical assumptions in the economic analyses that had little evidence to support them. The case of NICE's guidance on cholinesterase inhibitors highlights the importance of transparent and valid economic evaluations and the dangers of using inappropriate modelling technologies, basing analyses on a limited subset of the available data, and insufficiently reflecting the uncertainty in estimates that are intended to inform decision makers.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/economía , Inhibidores de la Colinesterasa/economía , Inhibidores de la Colinesterasa/uso terapéutico , Análisis Costo-Beneficio , Economía Farmacéutica , Humanos , Modelos Estadísticos , National Institutes of Health (U.S.) , Años de Vida Ajustados por Calidad de Vida , Estados Unidos
18.
Semin Oncol ; 44(3): 204-217, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-29248132

RESUMEN

Metabolic heterogeneity between neoplastic cells and surrounding stroma has been described in several epithelial malignancies; however, the metabolic phenotypes of neoplastic lymphocytes and neighboring stroma in diffuse large B-cell lymphoma (DLBCL) is unknown. We investigated the metabolic phenotypes of human DLBCL tumors by using immunohistochemical markers of glycolytic and mitochondrial oxidative phosphorylation (OXPHOS) metabolism. The lactate importer MCT4 is a marker of glycolysis, whereas the lactate importer MCT1 and TOMM20 are markers of OXPHOS metabolism. Staining patterns were assessed in 33 DLBCL samples as well as 18 control samples (non-neoplastic lymph nodes). TOMM20 and MCT1 were highly expressed in neoplastic lymphocytes, indicating an OXPHOS phenotype, whereas non-neoplastic lymphocytes in the control samples did not express these markers. Stromal cells in DLBCL samples strongly expressed MCT4, displaying a glycolytic phenotype, a feature not seen in stromal elements of non-neoplastic lymphatic tissue. Furthermore, the differential expression of lactate exporters (MCT4) on tumor-associated stroma and lactate importers (MCT1) on neoplastic lymphocytes support the hypothesis that neoplastic cells are metabolically linked to the stroma likely via mutually beneficial reprogramming. MCT4 is a marker of tumor-associated stroma in neoplastic tissue. Our findings suggest that disruption of neoplastic-stromal cell metabolic heterogeneity including MCT1 and MCT4 blockade should be studied to determine if it could represent a novel treatment target in DLBCL.


Asunto(s)
Glucólisis , Linfoma de Células B Grandes Difuso/metabolismo , Mitocondrias/metabolismo , Fosforilación Oxidativa , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Humanos , Inmunohistoquímica , Linfocitos/metabolismo , Masculino , Proteínas de Transporte de Membrana/metabolismo , Persona de Mediana Edad , Proteínas del Complejo de Importación de Proteínas Precursoras Mitocondriales , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteínas Musculares/metabolismo , Receptores de Superficie Celular/metabolismo , Células del Estroma/metabolismo , Simportadores/metabolismo
19.
Circulation ; 111(9): 1106-13, 2005 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-15723981

RESUMEN

BACKGROUND: In the Eplerenone Post-Acute Myocardial Infarction Heart Failure Efficacy and Survival Study (EPHESUS), aldosterone blockade with eplerenone decreased mortality in patients with left ventricular systolic dysfunction and heart failure after acute myocardial infarction. The present study was performed to evaluate the cost-effectiveness of eplerenone compared with placebo in these patients. METHODS AND RESULTS: A total of 6632 patients with left ventricular systolic dysfunction and heart failure after acute myocardial infarction were randomized to eplerenone or placebo and followed up for a mean of 16 months. The coprimary end points were all-cause mortality and the composite of cardiovascular mortality/cardiovascular hospitalization. The evaluation of resource use included hospitalizations, outpatient services, and medications. Eplerenone was priced at the average wholesale price, 3.60 dollars per day. Survival beyond the trial period was estimated from data from the Framingham Heart Study, the Saskatchewan Health database, and the Worcester Heart Attack Registry. The incremental cost-effectiveness of eplerenone in cost per life-year and quality-adjusted life-year gained compared with placebo was estimated. The number of life-years gained with eplerenone was 0.1014 based on Framingham (95% CI, 0.0306 to 0.1740), 0.0636 with Saskatchewan (95% CI, 0.0229 to 0.1038), and 0.1337 with Worcester (95% CI, 0.0438 to 0.2252) data. Cost was 1391 dollars higher over the trial period in the eplerenone arm (95% CI, 656 to 2165) because of drug cost. The incremental cost-effectiveness ratio was 13,718 dollars per life-year gained with Framingham (96.7% under 50,000 dollars per life-year gained), 21,876 dollars with Saskatchewan, and 10,402 dollars with Worcester. CONCLUSIONS: Eplerenone compared with placebo in the treatment of heart failure after acute myocardial infarction is effective in reducing mortality and is cost-effective in increasing years of life by commonly used criteria.


Asunto(s)
Insuficiencia Cardíaca/tratamiento farmacológico , Infarto del Miocardio/complicaciones , Espironolactona/análogos & derivados , Disfunción Ventricular Izquierda/etiología , Anciano , Causas de Muerte , Comorbilidad , Análisis Costo-Beneficio , Método Doble Ciego , Costos de los Medicamentos , Eplerenona , Femenino , Costos de la Atención en Salud , Insuficiencia Cardíaca/economía , Insuficiencia Cardíaca/etiología , Humanos , Esperanza de Vida , Masculino , Persona de Mediana Edad , Mortalidad , Infarto del Miocardio/economía , Años de Vida Ajustados por Calidad de Vida , Espironolactona/economía , Espironolactona/uso terapéutico , Disfunción Ventricular Izquierda/economía
20.
FEBS Lett ; 580(26): 6182-6, 2006 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-17067582

RESUMEN

Hypoxia inducible factor-1alpha (HIF1alpha) plays a key role in the regulation of genes controlling oxygen supply, glucose metabolism and angiogenesis. Its expression in tumors appears to confer an adaptive advantage to their hypoxic microenvironment. We have evaluated the effect of the immunophilin ligands FK506 and cyclosporin A on HIF1alpha levels in different tumor cell lines. Our results indicate that both drugs are potent suppressors of HIF1alpha expression by accelerating the proteasomal degradation of the protein. Unexpectedly, the suppressive effect of these compounds was found to be independent of the presence of von Hippel Lindau factor and the degree of hydroxylation of the HIF1alpha protein. Moreover, HIF1alpha degradation induced by these compounds did not required ubiquitination, as it was also induced in E1 ligase-incompetent cells.


Asunto(s)
Ciclosporina/farmacología , Subunidad alfa del Factor 1 Inducible por Hipoxia/antagonistas & inhibidores , Tacrolimus/farmacología , Ubiquitina/fisiología , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/fisiología , Línea Celular Tumoral , Humanos , Hidroxilación , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Inmunosupresores/farmacología , Complejo de la Endopetidasa Proteasomal/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA