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1.
FASEB J ; 36(5): e22246, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35405035

RESUMEN

Sickling is the central pathogenic process of sickle cell disease (SCD), one of the most prevalent inherited hemolytic disorders. Having no easy access to antioxidants in the cytosol, elevated levels of reactive oxygen species (ROS) residing at the plasma membrane in sickle red blood cells (sRBCs) easily oxidize membrane proteins and thus contribute to sickling. Although the ubiquitin-proteasome system (UPS) is essential to rapidly clear ROS-damaged membrane proteins and maintain cellular homeostasis, the function and regulatory mechanism of the UPS for their clearance in sRBCs remains unidentified. Elevated levels of polyubiquitinated membrane-associated proteins in human sRBCs are reported here. High throughput and untargeted proteomic analyses of membrane proteins immunoprecipitated by ubiquitin antibodies detected elevated levels of ubiquitination of a series of proteins including cytoskeletal proteins, transporters, ROS-related proteins, and UPS machinery components in sRBCs. Polyubiquitination of membrane-associated catalase was increased in sRBCs, associated with decreased catalase activity and elevated ROS. Surprisingly, shuttling of p97 (ATP-dependent valosin-containing chaperone protein), a key component of the UPS to shuttle polyubiquitinated proteins from the membrane to cytosol for proteasomal degradation, was significantly impaired, resulting in significant accumulation of p97 along with polyubiquitinated proteins in the membrane of human sRBCs. Functionally, inhibition of p97 directly promoted accumulation of polyubiquitinated membrane-associated proteins, excessive ROS levels, and sickling in response to hypoxia. Overall, we revealed that p97 dysfunction underlies impaired UPS and contributes to oxidative stress in sRBCs.


Asunto(s)
Anemia de Células Falciformes , Estrés Oxidativo , Proteína que Contiene Valosina , Adenosina Trifosfatasas/metabolismo , Catalasa/metabolismo , Proteínas de Ciclo Celular/metabolismo , Humanos , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteómica , Control de Calidad , Especies Reactivas de Oxígeno , Ubiquitina/metabolismo , Proteína que Contiene Valosina/metabolismo
2.
Clin Lymphoma Myeloma Leuk ; 21(11): e895-e902, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34376374

RESUMEN

BACKGROUND: Major advances in the treatment of acute lymphoblastic leukemia (ALL) over the past decade have resulted in 5-year overall survival (OS) rates of 80% in mature B cell ALL, 50% in precursor B cell ALL, 50% to 60% in T cell ALL, and 60% to 70% in Philadelphia chromosome-positive (Ph+) ALL, as reported in studies from large, specialized centers. However, many patients treated in the community have limited access to novel therapies and stem cell transplantation (HSCT). PATIENTS AND METHODS: The purpose of this retrospective cohort analysis was to evaluate the clinical outcomes of patients ≥ 16 years with newly diagnosed ALL treated from October 2007 to June 2019 in the Harris County Health System, Houston, TX. RESULTS: One hundred forty-six patients were included, with newly diagnosed pre-B-ALL (n = 127), T-ALL (n = 18), and chronic myeloid leukemia and/or lymphoid blast crisis (n = 1). Median age was 35 years (16-82) at diagnosis, and 81(55%) were male. The majority of patients with pre-B ALL identified as Hispanic (n = 118, or 92%). Ninety-eight (67%) of patients were uninsured or indigent, receiving care under the county's financial assistance programs. Hyper-CVAD-based induction chemotherapy was administered in 134 (92%) of patients, while 9 (6%) were treated on different protocols, and 3 (2%) were not treated due to early death, or patient refusal. Imatinib was the most common TKI used in 17 of 30 or 57% of patients with Ph+ disease. Out of 137 evaluable for response patients, 117 (85%) achieved complete remission (CR + CRi), 19 (14%) had refractory disease, and 1 (1%) died within 4 weeks of diagnosis. Median follow-up time was 50 months (1.5-135). For the entire study cohort, the median duration of CR/CRi was 15.4 months. Out of 62 patients who were eligible for consolidative HSCT at first CR, 52 (89%) did not receive it, with lack of insurance being the most common reason (n = 29, or 56%). Barriers to utilization of novel therapies such as blinatumomab or CAR-T were also observed. Patient-caused delays in administration of chemotherapy and treatment interruptions of at least 30 days were seen in 31(23%) patients. At 1, 2, and 5 years, relapse rates were 37%, 56%, and 70%. Recurrent and/or refractory disease was the cause of death in most patients (n = 69 [85%]). Five-year EFS and OS rates were 22% and 38% for patients with pre-B ALL, 24% and 44% for patients with T ALL, and 13% and 27% for patients with Ph+ ALL. Median OS was significantly increased (not reached [NR] vs. 24 months; P = .00088) in patients with an indication for HSCT in first CR due to high-risk features who underwent HSCT, versus those who did not. CONCLUSION: Addressing barriers raised by socioeconomic disparities, increasing access to effective therapies, and including patients with ALL treated in the community in clinical trials may improve survival for underserved populations.


Asunto(s)
Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Hospitales de Condado , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
4.
Stem Cells ; 37(11): 1481-1491, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31529663

RESUMEN

Cellular therapy is a promising investigational modality to enhance poststroke recovery. We conducted a single-arm, phase I clinical trial to determine the safety and feasibility of intravenous (IV) administration of autologous bone marrow mononuclear cells (MNCs) after acute ischemic stroke (AIS). Patients with moderate severity of AIS underwent bone marrow harvest followed by IV reinfusion of MNCs within 24-72 hours of onset. A target dose of 10 million cells per kilogram was chosen based on preclinical data. Patients were followed up daily during hospitalization and at 1, 3, 6, 12, and 24 months for incidence of adverse events using laboratory, clinical (12 months), and radiological (24 months) parameters. The trial was powered to detect severe adverse events (SAEs) with incidences of at least 10% and planned to enroll 30 patients. Primary outcomes were study-related SAEs and the proportion of patients successfully completing study intervention. A propensity score-based matched control group was used for the estimation of effect size (ES) for day-90 modified Rankin score (mRS). There were no study-related SAEs and, based on a futility analysis, enrolment was stopped after 25 patients. All patients successfully completed study intervention and most received the target dose. Secondary analysis estimated the ES to be a reduction of 1 point (95% confidence interval: 0.33-1.67) in median day-90 mRS for treated patients as compared with the matched control group. Bone marrow harvest and infusion of MNCs is safe and feasible in patients with AIS. The estimated ES is helpful in designing future randomized controlled trials. Stem Cells 2019;37:1481-1491.


Asunto(s)
Células de la Médula Ósea/citología , Trasplante de Médula Ósea/efectos adversos , Isquemia Encefálica/terapia , Leucocitos Mononucleares/citología , Accidente Cerebrovascular/terapia , Administración Intravenosa , Anciano , Células de la Médula Ósea/fisiología , Trasplante de Médula Ósea/métodos , Isquemia Encefálica/diagnóstico por imagen , Imagen de Difusión Tensora , Estudios de Factibilidad , Femenino , Humanos , Leucocitos Mononucleares/fisiología , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/diagnóstico por imagen , Resultado del Tratamiento
5.
Blood Adv ; 2(15): 1957-1968, 2018 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-30097462

RESUMEN

Although excessive plasma adenosine is detrimental in sickle cell disease (SCD), the molecular mechanism underlying elevated circulating adenosine remains unclear. Here we report that the activity of soluble CD73, an ectonucleotidase producing extracellular adenosine, was significantly elevated in a murine model of SCD and correlated with increased plasma adenosine. Mouse genetic studies demonstrated that CD73 activity contributes to excessive induction of plasma adenosine and thereby promotes sickling, hemolysis, multiorgan damage, and disease progression. Mechanistically, we showed that erythrocyte adenosine 5'-monophosphate-activated protein kinase (AMPK) was activated both in SCD patients and in the murine model of SCD. AMPK functions downstream of adenosine receptor ADORA2B signaling and contributes to sickling by regulating the production of erythrocyte 2,3-bisphosphoglycerate (2,3-BPG), a negative allosteric regulator of hemoglobin-O2 binding affinity. Preclinically, we reported that treatment of α,ß-methylene adenosine 5'-diphosphate, a potent CD73 specific inhibitor, significantly decreased sickling, hemolysis, multiorgan damage, and disease progression in the murine model of SCD. Taken together, both human and mouse studies reveal a novel molecular mechanism contributing to the pathophysiology of SCD and identify potential therapeutic strategies to treat SCD.


Asunto(s)
5'-Nucleotidasa , Adenosina Trifosfato/análogos & derivados , Anemia de Células Falciformes , Eritrocitos/enzimología , 2,3-Difosfoglicerato/metabolismo , 5'-Nucleotidasa/antagonistas & inhibidores , 5'-Nucleotidasa/genética , 5'-Nucleotidasa/metabolismo , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Adenosina/metabolismo , Adenosina Trifosfato/farmacología , Anemia de Células Falciformes/tratamiento farmacológico , Anemia de Células Falciformes/enzimología , Anemia de Células Falciformes/genética , Anemia de Células Falciformes/patología , Animales , Eritrocitos/patología , Femenino , Proteínas Ligadas a GPI/antagonistas & inhibidores , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/metabolismo , Humanos , Masculino , Ratones , Ratones Noqueados , Receptor de Adenosina A2B/genética , Receptor de Adenosina A2B/metabolismo
6.
Sci Rep ; 7(1): 15281, 2017 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-29127281

RESUMEN

Elevated sphingosine 1-phosphate (S1P) is detrimental in Sickle Cell Disease (SCD), but the mechanistic basis remains obscure. Here, we report that increased erythrocyte S1P binds to deoxygenated sickle Hb (deoxyHbS), facilitates deoxyHbS anchoring to the membrane, induces release of membrane-bound glycolytic enzymes and in turn switches glucose flux towards glycolysis relative to the pentose phosphate pathway (PPP). Suppressed PPP causes compromised glutathione homeostasis and increased oxidative stress, while enhanced glycolysis induces production of 2,3-bisphosphoglycerate (2,3-BPG) and thus increases deoxyHbS polymerization, sickling, hemolysis and disease progression. Functional studies revealed that S1P and 2,3-BPG work synergistically to decrease both HbA and HbS oxygen binding affinity. The crystal structure at 1.9 Å resolution deciphered that S1P binds to the surface of 2,3-BPG-deoxyHbA and causes additional conformation changes to the T-state Hb. Phosphate moiety of the surface bound S1P engages in a highly positive region close to α1-heme while its aliphatic chain snakes along a shallow cavity making hydrophobic interactions in the "switch region", as well as with α2-heme like a molecular "sticky tape" with the last 3-4 carbon atoms sticking out into bulk solvent. Altogether, our findings provide functional and structural bases underlying S1P-mediated pathogenic metabolic reprogramming in SCD and novel therapeutic avenues.


Asunto(s)
Anemia de Células Falciformes/metabolismo , Eritrocitos Anormales/metabolismo , Hemoglobina A/metabolismo , Hemoglobina Falciforme/metabolismo , Lisofosfolípidos/metabolismo , Esfingosina/análogos & derivados , 2,3-Difosfoglicerato/química , 2,3-Difosfoglicerato/metabolismo , Anemia de Células Falciformes/patología , Animales , Eritrocitos Anormales/patología , Femenino , Hemoglobina A/química , Hemoglobina Falciforme/química , Hemólisis , Humanos , Lisofosfolípidos/química , Masculino , Ratones , Ratones Transgénicos , Estrés Oxidativo , Vía de Pentosa Fosfato , Esfingosina/química , Esfingosina/metabolismo
7.
Sci Rep ; 6: 29637, 2016 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-27436223

RESUMEN

Although Lands' cycle was discovered in 1958, its function and cellular regulation in membrane homeostasis under physiological and pathological conditions remain largely unknown. Nonbiased high throughput metabolomic profiling revealed that Lands' cycle was impaired leading to significantly elevated erythrocyte membrane lysophosphatidylcholine (LysoPC) content and circulating and erythrocyte arachidonic acid (AA) in mice with sickle cell disease (SCD), a prevalent hemolytic genetic disorder. Correcting imbalanced Lands' cycle by knockdown of phospholipase 2 (cPLA2) or overexpression of lysophosphatidycholine acyltransferase 1 (LPCAT1), two key enzymes of Lands' cycle in hematopoietic stem cells, reduced elevated erythrocyte membrane LysoPC content and circulating AA levels and attenuated sickling, inflammation and tissue damage in SCD chimeras. Human translational studies validated SCD mouse findings and further demonstrated that imbalanced Lands' cycle induced LysoPC production directly promotes sickling in cultured mouse and human SCD erythrocytes. Mechanistically, we revealed that hypoxia-mediated ERK activation underlies imbalanced Lands' cycle by preferentially inducing the activity of PLA2 but not LPCAT in human and mouse SCD erythrocytes. Overall, our studies have identified a pathological role of imbalanced Lands' cycle in SCD erythrocytes, novel molecular basis regulating Lands' cycle and therapeutic opportunities for the disease.


Asunto(s)
Anemia de Células Falciformes/metabolismo , Ácido Araquidónico/sangre , Eritrocitos/metabolismo , Lisofosfatidilcolinas/metabolismo , Metabolómica/métodos , 1-Acilglicerofosfocolina O-Aciltransferasa/genética , Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/genética , Animales , Hipoxia de la Célula , Células Cultivadas , Modelos Animales de Enfermedad , Femenino , Técnicas de Silenciamiento del Gen , Fosfolipasas A2 Grupo IV/genética , Humanos , Masculino , Ratones
9.
Blood ; 125(10): 1643-52, 2015 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-25587035

RESUMEN

Erythrocyte possesses high sphingosine kinase 1 (SphK1) activity and is the major cell type supplying plasma sphingosine-1-phosphate, a signaling lipid regulating multiple physiological and pathological functions. Recent studies revealed that erythrocyte SphK1 activity is upregulated in sickle cell disease (SCD) and contributes to sickling and disease progression. However, how erythrocyte SphK1 activity is regulated remains unknown. Here we report that adenosine induces SphK1 activity in human and mouse sickle and normal erythrocytes in vitro. Next, using 4 adenosine receptor-deficient mice and pharmacological approaches, we determined that the A2B adenosine receptor (ADORA2B) is essential for adenosine-induced SphK1 activity in human and mouse normal and sickle erythrocytes in vitro. Subsequently, we provide in vivo genetic evidence that adenosine deaminase (ADA) deficiency leads to excess plasma adenosine and elevated erythrocyte SphK1 activity. Lowering adenosine by ADA enzyme therapy or genetic deletion of ADORA2B significantly reduced excess adenosine-induced erythrocyte SphK1 activity in ADA-deficient mice. Finally, we revealed that protein kinase A-mediated extracellular signal-regulated kinase 1/2 activation functioning downstream of ADORA2B underlies adenosine-induced erythrocyte SphK1 activity. Overall, our findings reveal a novel signaling network regulating erythrocyte SphK1 and highlight innovative mechanisms regulating SphK1 activity in normal and SCD.


Asunto(s)
Adenosina/sangre , Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/enzimología , Eritrocitos Anormales/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/sangre , Receptor de Adenosina A2B/sangre , Adenosina Desaminasa/sangre , Adenosina Desaminasa/deficiencia , Adenosina Desaminasa/genética , Adenosina-5'-(N-etilcarboxamida)/farmacología , Agammaglobulinemia/sangre , Agammaglobulinemia/enzimología , Agammaglobulinemia/genética , Anemia de Células Falciformes/genética , Animales , Células Cultivadas , Proteínas Quinasas Dependientes de AMP Cíclico/sangre , Eritrocitos/efectos de los fármacos , Eritrocitos/enzimología , Eritrocitos/metabolismo , Eritrocitos Anormales/efectos de los fármacos , Eritrocitos Anormales/enzimología , Hemoglobina Falciforme/genética , Hemoglobina Falciforme/metabolismo , Humanos , Sistema de Señalización de MAP Quinasas , Ratones , Ratones Noqueados , Ratones Transgénicos , Modelos Biológicos , Receptor de Adenosina A2B/deficiencia , Receptor de Adenosina A2B/genética , Inmunodeficiencia Combinada Grave/sangre , Inmunodeficiencia Combinada Grave/enzimología , Inmunodeficiencia Combinada Grave/genética , Transducción de Señal
10.
J Clin Invest ; 124(6): 2750-61, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24837436

RESUMEN

Sphingosine-1-phosphate (S1P) is a bioactive lipid that regulates multicellular functions through interactions with its receptors on cell surfaces. S1P is enriched and stored in erythrocytes; however, it is not clear whether alterations in S1P are involved in the prevalent and debilitating hemolytic disorder sickle cell disease (SCD). Here, using metabolomic screening, we found that S1P is highly elevated in the blood of mice and humans with SCD. In murine models of SCD, we demonstrated that elevated erythrocyte sphingosine kinase 1 (SPHK1) underlies sickling and disease progression by increasing S1P levels in the blood. Additionally, we observed elevated SPHK1 activity in erythrocytes and increased S1P in blood collected from patients with SCD and demonstrated a direct impact of elevated SPHK1-mediated production of S1P on sickling that was independent of S1P receptor activation in isolated erythrocytes. Together, our findings provide insights into erythrocyte pathophysiology, revealing that a SPHK1-mediated elevation of S1P contributes to sickling and promotes disease progression, and highlight potential therapeutic opportunities for SCD.


Asunto(s)
Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/etiología , Lisofosfolípidos/sangre , Esfingosina/análogos & derivados , Anemia de Células Falciformes/genética , Animales , Antidrepanocíticos/farmacología , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Inhibidores Enzimáticos/farmacología , Eritrocitos Anormales/efectos de los fármacos , Eritrocitos Anormales/metabolismo , Técnicas de Silenciamiento del Gen , Hemólisis/efectos de los fármacos , Humanos , Metabolómica , Metanol , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Ratones Transgénicos , Fosfotransferasas (Aceptor de Grupo Alcohol)/antagonistas & inhibidores , Fosfotransferasas (Aceptor de Grupo Alcohol)/sangre , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Pirrolidinas/farmacología , Transducción de Señal , Esfingosina/sangre , Sulfonas/farmacología
11.
JSLS ; 18(1): 125-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24680155

RESUMEN

INTRODUCTION: Portal vein thrombosis (PVT) is a relatively uncommon complication after abdominal surgery. CASE REPORT: We report an even more unusual case of PVT 10 days after an uncomplicated laparoscopic cholecystectomy, believed to be only the fourth reported case in the literature of this rare complication. CONCLUSION: Albeit extremely rare, PVT should be included in the differential diagnosis for abdominal symptoms and/or elevated hepatic function tests after laparoscopic cholecystectomy.


Asunto(s)
Colecistectomía Laparoscópica/efectos adversos , Vena Porta , Trombosis de la Vena/etiología , Adulto , Colelitiasis/cirugía , Femenino , Fibrinolíticos/uso terapéutico , Humanos , Complicaciones Posoperatorias , Trombosis de la Vena/tratamiento farmacológico
12.
Cancer Genet ; 205(10): 519-22, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22944561

RESUMEN

We report an unusual case of a symptomatic patient who initially had high hemoglobin and low serum erythropoietin levels, fitting a clinical diagnosis of polycythemia vera. However, after treatment with hydroxyurea and serial phlebotomies had been started, the patient developed hypereosinophilia, fitting the category of a myeloproliferative neoplasm with eosinophilia associated with the FIP1L1-PDGFRA gene fusion, as confirmed by molecular analysis. We discuss the clinical presentation, evolution, response to treatment, and pathogenetic implications of this case.


Asunto(s)
Eosinofilia/diagnóstico , Eosinofilia/genética , Trastornos Mieloproliferativos/genética , Policitemia Vera/diagnóstico , Policitemia Vera/genética , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Factores de Escisión y Poliadenilación de ARNm/genética , Antineoplásicos/uso terapéutico , Benzamidas , Biopsia , Eosinofilia/complicaciones , Predisposición Genética a la Enfermedad , Humanos , Mesilato de Imatinib , Masculino , Persona de Mediana Edad , Modelos Genéticos , Mutación , Trastornos Mieloproliferativos/complicaciones , Trastornos Mieloproliferativos/diagnóstico , Piperazinas/uso terapéutico , Policitemia Vera/complicaciones , Pirimidinas/uso terapéutico , Inducción de Remisión
13.
Nat Med ; 17(1): 79-86, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21170046

RESUMEN

Hypoxia can act as an initial trigger to induce erythrocyte sickling and eventual end organ damage in sickle cell disease (SCD). Many factors and metabolites are altered in response to hypoxia and may contribute to the pathogenesis of the disease. Using metabolomic profiling, we found that the steady-state concentration of adenosine in the blood was elevated in a transgenic mouse model of SCD. Adenosine concentrations were similarly elevated in the blood of humans with SCD. Increased adenosine levels promoted sickling, hemolysis and damage to multiple tissues in SCD transgenic mice and promoted sickling of human erythrocytes. Using biochemical, genetic and pharmacological approaches, we showed that adenosine A(2B) receptor (A(2B)R)-mediated induction of 2,3-diphosphoglycerate, an erythrocyte-specific metabolite that decreases the oxygen binding affinity of hemoglobin, underlies the induction of erythrocyte sickling by excess adenosine both in cultured human red blood cells and in SCD transgenic mice. Thus, excessive adenosine signaling through the A(2B)R has a pathological role in SCD. These findings may provide new therapeutic possibilities for this disease.


Asunto(s)
Adenosina/fisiología , Anemia de Células Falciformes/fisiopatología , Adenosina/sangre , Adenosina/uso terapéutico , Adenosina/toxicidad , Adenosina Desaminasa/deficiencia , Adenosina Desaminasa/uso terapéutico , Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/tratamiento farmacológico , Animales , Hemólisis , Humanos , Riñón/efectos de los fármacos , Riñón/patología , Hígado/efectos de los fármacos , Hígado/patología , Pulmón/efectos de los fármacos , Pulmón/patología , Ratones , Ratones Noqueados , Ratones Transgénicos , Receptor de Adenosina A2B/fisiología , Transducción de Señal/fisiología , Bazo/efectos de los fármacos , Bazo/patología , Xantinas/uso terapéutico
14.
J Neurooncol ; 94(1): 149-52, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19219404

RESUMEN

Primary brain tumor patients have multiple risk factors for Pneumocystis jiroveci and may require prophylaxis with TMP-SMZ or dapsone. Although dapsone is generally safe and efficacious, we present a case of a patient diagnosed with a brain stem glioblastoma who developed methemoglobinemia and haemolytic anemia after presenting with worsening confusion and cardiopulmonary system dysfunction. This case highlights one of the potentially severe complications associated with dapsone therapy. Although this illustrates an unusual toxicity of dapsone, a high index of suspicion should be given to high-risk patients due to ethnic heritage, anemia, or advanced age. Furthermore, given the toxicities of TMP-SMZ and dapsone, further work is needed to determine the threshold CD4(+) count at which empiric prophylaxis should be initiated.


Asunto(s)
Antiinfecciosos/efectos adversos , Neoplasias del Tronco Encefálico/complicaciones , Dapsona/efectos adversos , Glioblastoma/complicaciones , Metahemoglobinemia/inducido químicamente , Metahemoglobinemia/complicaciones , Neoplasias del Tronco Encefálico/tratamiento farmacológico , Glioblastoma/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad
15.
Atherosclerosis ; 198(2): 294-300, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18342864

RESUMEN

OBJECTIVE: Prospective studies have reported a positive association of coagulation factors with risk of coronary heart disease (CHD). It is unclear whether these coagulation factors interact. METHODS AND RESULTS: Using a prospective case-cohort design, we analyzed by Cox proportional hazard regression interactions between soluble thrombomodulin (sTM) and fibrinogen, factor VIII (FVIII), FVII, or plasminogen activator inhibitor-1 (PAI-1) in 410 CHD cases and 721 non-cases from the Atherosclerosis Risk in Communities (ARIC). There was a significant interaction between sTM and fibrinogen (p=0.027). We next assessed risk ratios (RR) by combined tertile analysis. Combined analysis revealed that being in the upper sTM tertile counteracted the CHD risk imposed by higher fibrinogen whereas being in the lower sTM tertile amplified the CHD risk of higher fibrinogen. sTM and fibrinogen mutually influenced CHD incidence in a concentration-dependent manner. When analyzed as single factors by tertiles, FVIII, FVII and PAI-1 were not associated with CHD. However, when analyzed together with sTM, FVIII and PAI-1 were both positively associated with CHD for those in the lower sTM tertile. CONCLUSION: There is a complex interaction between sTM and prothrombotic coagulation factors. Combined analysis improves CHD risk assessment.


Asunto(s)
Factores de Coagulación Sanguínea/análisis , Enfermedad Coronaria/sangre , Enfermedad Coronaria/epidemiología , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Medición de Riesgo , Estados Unidos/epidemiología
16.
Hematology ; 11(5): 361-3, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17607587

RESUMEN

Hematopoietic stem cell transplant has been used in the treatment of multiple myeloma. Its use in the treatment of POEMS syndrome is still under investigation. We describe the clinical course and long term follow-up of a patient with POEMS syndrome unresponsive to standard chemotherapy. The patient had rapid and dramatic improvement in neuropathy and dermatologic features after autologous stem cell transplantation. A review of the literature is also presented. High-dose chemotherapy followed by stem cell transplantation is a potential treatment option for patients with POEMS syndrome.


Asunto(s)
Síndrome POEMS/terapia , Trasplante de Células Madre de Sangre Periférica , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Inducción de Remisión , Trasplante Autólogo , Resultado del Tratamiento
18.
Am Heart J ; 144(2): 233-8, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12177639

RESUMEN

BACKGROUND: Recent evidence implicates inflammation in the pathogenesis of coronary heart disease (CHD). C-reactive protein, a plasma marker of inflammation, is a marker of CHD risk but has been studied in few prospective investigations of the general population. METHODS AND RESULTS: We prospectively examined the association of CRP with incident CHD among middle-aged adults in the Atherosclerosis Risk In Communities (ARIC) study. With the use of a nested case-cohort approach, we measured CRP in stored, baseline blood samples of 2 groups of subjects in whom CHD developed during follow-up (242 incident cases from 1987 to 1993 and 373 from 1990 to 1995) and, for comparison, 2 stratified random samples of noncases. In analyses adjusted for demographic variables and traditional CHD risk factors, the relative risk of CHD across quintiles of CRP was 1.0, 0.8, 1.6, 1.9, and 1.5 for events from 1987 to 1995 (P for trend =.01). As expected, inclusion of fibrinogen, intracellular adhesion molecule-1, and white blood cell count (other potential markers of the inflammatory reaction) attenuated the association of CRP with CHD incidence. In a supplemental cross-sectional analysis, CRP was not associated with carotid intima-media thickness after adjustment for major risk factors. CONCLUSIONS: C-reactive protein is a moderately strong marker of risk of CHD in this cohort of middle-aged adults, consistent with the role of inflammation in the pathogenesis of CHD events. The association was not specific to CRP because other markers of inflammation could largely account for the finding.


Asunto(s)
Proteína C-Reactiva/análisis , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/epidemiología , Anciano , Biomarcadores/análisis , Enfermedades de las Arterias Carótidas/epidemiología , Estudios de Casos y Controles , Estudios de Cohortes , Comorbilidad , Enfermedad de la Arteria Coronaria/diagnóstico , Estudios Transversales , Diabetes Mellitus/epidemiología , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Análisis de Regresión , Factores de Riesgo , Estados Unidos/epidemiología
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