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1.
Nutr Cancer ; 65(5): 653-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23859032

RESUMEN

Although poor nutritional status and weight loss in cancer patients is known to affect outcomes, little is known about malnutrition differences based on geographic location. We investigated nutritional and inflammatory status of 220 newly diagnosed adults with solid tumors at the University of Kentucky's Markey Cancer Center during December 2008 through October 2011. Chi-square tests were used to determine any associations between suboptimal nutritional levels and rural-urban areas of residence. Out of the 13 lab values collected, the only significant difference between rural and urban participants was found for vitamin D resulting in more rural subjects (67.4%) having a suboptimal vitamin D status as compared to those residing in urban areas (53.3%, P = 0.04). Controlling for baseline demographics including age, race, sex, body mass index, nutritional status, and type of cancer, logistic regression analyses concluded those in rural areas had nearly a twofold increase in the odds of having a suboptimal vitamin D level compared to those in urban areas (odd's ratio = 1.97; 95% confidence interval = 1.04, 3.74). Further investigation into the rural-urban differences in vitamin D needs to be investigated in order to improve outcomes during cancer treatment.


Asunto(s)
Neoplasias/sangre , Estado Nutricional , Deficiencia de Vitamina D/epidemiología , Vitamina D/sangre , Anciano , Índice de Masa Corporal , Estudios de Cohortes , Femenino , Humanos , Kentucky/epidemiología , Modelos Logísticos , Masculino , Micronutrientes/sangre , Micronutrientes/deficiencia , Persona de Mediana Edad , Neoplasias/diagnóstico , Neoplasias/epidemiología , Oportunidad Relativa , Prevalencia , Población Rural , Factores Socioeconómicos , Encuestas y Cuestionarios , Población Urbana , Vitamina D/administración & dosificación , Deficiencia de Vitamina D/sangre
2.
J Investig Med ; 49(2): 173-83, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11288758

RESUMEN

BACKGROUND: Correction of anemia in hemodialysis patients is seldom completely attained, and the response of parameters other than hemoglobin concentration to anemia correction has not been evaluated in detail. METHODS: Laboratory parameters that suggest iron deficiency occurred in 10-15% of 206 recombinant human erythropoietin (rhEPO)-treated patients. Oral iron was given for 9 months and intravenous iron thereafter on a patient-specific basis when iron deficiency was evident. Eighty-seven hemodialysis patients with data for 12 months were followed for another 12 months. A computerized information system enabled data management and analysis. RESULTS: With oral iron, serum ferritin decreased (P < 0.001), indicating further iron depletion. With intravenous iron, hemoglobin increased, evidence of iron deficiency decreased, and less rhEPO was needed. Striking macrocytosis appeared. Serum albumin and serum creatinine/kg body weight (an index of muscle mass) increased, while blood pressure decreased. Data were reanalyzed in four mean corpuscular volume (MCV) quartiles and two ferritin subsets at study onset. Iron deficient erythropoiesis (low MCV, mean corpuscular hemoglobin [MCH], and transferrin saturation) was striking in quartile 1; low ferritin was prevalent in all quartiles. With intravenous iron, hemoglobin increased only in quartile 1, the quartile with the greatest decrease (52%) in rhEPO dose. MCV increased in all quartiles (P < 0.001). Serum albumin increased in all MCV quartiles and both ferritin subsets, but significant creatinine/kg increase and blood pressure decrease occurred only in the low-ferritin subset. CONCLUSIONS: Macrocytosis occurred with intravenous iron replacement. The universal MCV increase suggests unrecognized, inadequately treated, folic acid deficiency unmasked by an adequate iron supply. There was also improved well being. Effects were most clearly evident in patients with deficient iron stores.


Asunto(s)
Anemia Ferropénica/tratamiento farmacológico , Hierro/administración & dosificación , Diálisis Renal/efectos adversos , Administración Oral , Anciano , Anciano de 80 o más Años , Anemia Ferropénica/sangre , Anemia Ferropénica/diagnóstico , Eritropoyetina/uso terapéutico , Hospitalización , Humanos , Inyecciones Intravenosas , Hierro/efectos adversos , Persona de Mediana Edad , Proteínas Recombinantes
3.
Artículo en Inglés | MEDLINE | ID: mdl-10942618

RESUMEN

Anaemia is a common finding in infected individuals, and in many cases is an indicator of disease activity and/or duration. The term 'anaemia of infection' refers to a specific syndrome related to the more broadly defined 'anaemia of chronic disease'. In this syndrome, cytokines produced as part of the host response to infection induce anaemia by well-defined pathophysiological mechanisms. In this chapter, the diagnosis, significance, pathophysiology and treatment of the anaemia of infection will be reviewed. Other mechanisms which can produce anaemia in infected individuals will also be reviewed.


Asunto(s)
Anemia/etiología , Infecciones/complicaciones , Anemia/inducido químicamente , Anemia/diagnóstico , Antiinfecciosos/efectos adversos , Citocinas/efectos adversos , Citocinas/sangre , Citocinas/fisiología , Humanos
4.
J Investig Med ; 47(9): 477-83, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10572378

RESUMEN

BACKGROUND: To determine the concentrations of tumor necrosis factor (TNF) alpha, soluble TNF receptors (sTNFR), interleukin (IL)-1 beta, gamma-interferon (IFN), macrophage inflammatory protein (MIP)-1 alpha, MIP-1 beta, and RANTES to which hematopoietic progenitors are exposed in vivo in HIV patients and the correlation of these concentrations with hematologic parameters, cytokine and cytokine receptor concentrations were measured by ELISA in bone marrow aspirate supernatants from 19 HIV patients undergoing diagnostic evaluation and 14 healthy paid volunteer controls. IL-1 beta and gamma-IFN were rarely detectable. All cytokines/receptors detectable in marrow supernatant, except RANTES, showed mean concentrations 1.6- to 6.2-fold higher in patients with HIV compared to healthy controls. METHODS: Elevated TNF-alpha and MIP-1 beta were associated with marrow involvement by lymphoma, Hodgkin disease, or mycobacterial infection. Concentrations of all cytokines/receptors measured correlated with the severity of anemia. CD8+ lymphocytes were inversely correlated with concentrations of all cytokines measured other than MIP-1 alpha. To identify differences specific to HIV infection, marrow supernatant cytokine concentrations were also evaluated in 9 non-HIV patients undergoing diagnostic marrow examination. Significant differences were observed in TNF alpha, MIP-1 alpha, and IL-1 beta concentrations. RESULTS: These studies demonstrate that concentrations of these cytokines and receptors are elevated in bone marrow supernatant of HIV-infected patients with hematologic abnormalities, and that these concentrations correlate with clinical parameters in these patients. CONCLUSIONS: Evaluation of local concentrations of cytokines may be relevant to understanding tissue-specific pathology in HIV-infected individuals.


Asunto(s)
Médula Ósea/metabolismo , Citocinas/metabolismo , Infecciones por VIH/metabolismo , Receptores de Citocinas/metabolismo , Adulto , Biomarcadores , Biopsia con Aguja , Médula Ósea/patología , Diagnóstico Diferencial , Ensayo de Inmunoadsorción Enzimática , Femenino , Infecciones por VIH/patología , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad
5.
Alcohol ; 19(1): 57-63, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10487389

RESUMEN

Alcoholics have increased susceptibility to infections including tuberculosis. Chronic alcohol treatment impairs host response to bovine mycobacterium infection from BCG. This study assesses the role of four cytokines (TNFalpha, IFNgamma, IL-4, and IL-10) in this impaired response. Twenty male C57BL/6 mice were pair-fed on the Lieber DiCarli control (LCD) or ethanol (LED) diets for 28 days. The LED treated subjects ate ad lib and consumed a mean of 13 g/kg/d of ethanol. After 14 days, based on body weight, subjects were randomly divided into four treatment groups of five each. Ten infected with 2x10(6) colony-forming units (CFU) of BCG by tail-vein. On day 28, the mice were sacrificed. Liver was cultured to determine the mycobacteria CFU/g tissue. Spleens were assayed for the levels of TNFalpha, IFNgamma, IL-4, and IL-10 mRNA relative to mRNA levels for a housekeeping gene using a quantitative reverse transcriptase PCR. Without BCG infection, only the mRNA for IFNgamma was increased by LED treatment, 51% (p = 0.0001). BCG infection significantly increased TNFalpha, IFNgamma, and IL-10 mRNA (p<0.0001). IL-4 mRNA decreased (p = 0.0006). Chronic LED plus BCG infection further increased TNFalpha (p = 0.002) and IFN-gamma (p = 0.04); IL-10 was unchanged, whereas IL-4 was marginally further decreased (p = 0.06). CFU/liver increased with LED (mean +/- SD, 72+/-33x10(5) vs. 39+/-17x10(5); p = 0.004). A significant direct correlation was observed between CFU and TNFalpha, r = 0.70, p = 0.03. In conclusion, BCG infection increases TNFalpha, IFNgamma, & IL-10 and decreases IL-4. CFU numbers correlate with mRNA for TNFalpha, and LED inhibits host containment of BCG infection as measured by liver CFU. This study could not identify cytokine alterations in either Th1- or Th2-type immune responses that might contribute to the impaired host response to the BCG infection.


Asunto(s)
Depresores del Sistema Nervioso Central/administración & dosificación , Citocinas/efectos de los fármacos , Etanol/administración & dosificación , Mycobacterium bovis/inmunología , Tuberculosis/inmunología , Animales , Bovinos , Recuento de Colonia Microbiana , Citocinas/inmunología , Interferón gamma/efectos de los fármacos , Interferón gamma/metabolismo , Interleucina-10/metabolismo , Interleucina-4/metabolismo , Hepatopatías/metabolismo , Hepatopatías/microbiología , Masculino , Ratones , Ratones Endogámicos C57BL , ARN Mensajero/efectos de los fármacos , ARN Mensajero/inmunología , Bazo/metabolismo , Tuberculosis/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
6.
Int J Hematol ; 70(1): 7-12, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10446488

RESUMEN

The anemia found in patients with chronic infectious, inflammatory, and neoplastic disorders, known as the anemia of chronic disease (ACD), is one of the most common syndromes in medicine. A characteristic finding of the disorders associated with ACD is increased production of the cytokines that mediate the immune or inflammatory response, such as tumor necrosis factor, interleukin-1, and the interferons. All the processes involved in the development of ACD can be attributed to these cytokines, including shortened red cell survival, blunted erythropoietin response to anemia, impaired erythroid colony formation in response to erythropoietin, and abnormal mobilization of reticuloendothelial iron stores. In this review, advances in the understanding of the diagnostic, pathophysiologic, and therapeutic aspects of this syndrome are summarized.


Asunto(s)
Anemia/etiología , Citocinas/farmacología , Anemia/fisiopatología , Anemia/terapia , Supervivencia Celular , Enfermedad Crónica , Citocinas/uso terapéutico , Diagnóstico Diferencial , Eritrocitos/fisiología , Eritropoyetina/farmacología , Humanos , Inflamación , Síndrome
7.
Clin Lab Haematol ; 21(3): 161-7, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10448597

RESUMEN

Serum soluble transferrin receptor (sTfR) concentration has been evaluated in the diagnosis of iron deficiency in otherwise healthy individuals and in patients with rheumatoid arthritis, but has not been studied in a general population of patients with complicated clinical presentations. In this study, 145 anaemic patients with a variety of medical conditions undergoing diagnostic bone marrow aspiration for any reason were tested by a complete blood count, a panel of biochemical tests to evaluate iron status, bone-marrow aspirate iron stain, and serum sTfR concentration. Sixteen per cent lacked stainable iron in the marrow aspirate. All biochemical parameters differed significantly between patients with or without stainable marrow iron. The sTfR assay was significantly more sensitive but less specific than other iron status assays in identifying the absence of stainable iron. Logistic regression analysis demonstrated that only sTfR and ferritin contributed independently to the prediction of marrow iron status. Serum ferritin alone was highly specific but insensitive. A decision algorithm combining serum ferritin and sTfR was as sensitive as TfR and as specific as serum ferritin. The measurement of serum sTfR, especially in conjunction with serum ferritin, is a valuable addition to the existing methods for predicting the results of marrow aspirate iron stains.


Asunto(s)
Anemia/sangre , Deficiencias de Hierro , Receptores de Transferrina/sangre , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores , Biopsia con Aguja , Médula Ósea/metabolismo , Médula Ósea/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas
8.
Exp Hematol ; 27(7): 1133-8, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10390188

RESUMEN

In previous studies, we have demonstrated that the inhibitory effects of tumor necrosis factor (TNF) and interleukin (IL)-1 on human erythroid colony formation are indirect and mediated by beta and gamma interferon (IFN), respectively, which act directly upon erythroid colony forming units (CFU-E). The in vitro inhibitory effect of gammaIFN but not betaIFN is reversed by exposure to high concentrations of recombinant human (rh) erythropoietin (EPO). Ceramide, a product of sphingomyelin hydrolysis, is a known mediator of apoptotic effects of TNF, IL-1, and gammaIFN. In this report, the effects of ceramide on CFU-E colony formation and its implication in the model described above are evaluated. Endogenous ceramide produced by exposure to bacterial sphingomyelinase (0.2-2.0 U/mL) and exogenous cell-permeable ceramide (C2-ceramide; 5 and 10 mM) significantly inhibited bone marrow CFU-E colony formation. This effect was reversed by the ceramide antagonist sphingosine-1-phosphate (S-1-P). Inhibition of CFU-E by rhgammaIFN, but not rhbetaIFN, was significantly reversed by S-1-P. rhEPO 10 U/mL reversed CFU-E inhibition by C2-ceramide 10 mM. Exposure of marrow cells to rhgammaIFN led to a 57% increase in ceramide content. The present study demonstrates that colony formation by human CFU-E is inhibited by endogenous and exogenous ceramide, and that inhibition by rhgammaIFN can be reversed by the ceramide antagonist S-1-P. Inhibition of CFU-E colony formation by ceramide and by are both reversed by high concentrations of rhEPO. These findings strongly suggest that ceramide mediates inhibition of human CFU-E colony formation by gammaIFN.


Asunto(s)
Ceramidas/farmacología , Células Precursoras Eritroides/efectos de los fármacos , Eritropoyesis/efectos de los fármacos , Lisofosfolípidos , Esfingosina/análogos & derivados , Apoptosis/efectos de los fármacos , Ceramidas/antagonistas & inhibidores , Ceramidas/fisiología , Ensayo de Unidades Formadoras de Colonias , Depresión Química , Eritropoyetina/antagonistas & inhibidores , Eritropoyetina/farmacología , Humanos , Interferón beta/farmacología , Interferón gamma/farmacología , Proteínas Recombinantes/farmacología , Esfingomielina Fosfodiesterasa/farmacología , Esfingosina/farmacología , Receptor fas/fisiología
11.
Transgenic Res ; 7(4): 229-38, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9859212

RESUMEN

Lung Kruppel-like factor (LKLF) is a member of the Kruppel-like family of zinc finger transcription factors and is closely related to erythroid kruppel-like factor (EKLF), which is necessary for beta-globin gene expression. While EKLF is expressed exclusively in erythroid cells, LKLF is expressed temporally during early embryonic development and predominantly in the adult mouse lung. To understand the role this novel transcription factor plays in development as well as tissue differentiation and function, animals lacking LKLF were produced using gene targeting technology. Mice lacking LKLF die in utero between day 11.5 and 13.5 of embryonic life and exhibit retarded growth, craniofacial abnormalities, abdominal bleeding and signs of anaemia. Although the yolk sac erythropoiesis is normal in mutant embryos, in vitro fetal liver cultures of these embryos fail to give rise to erythroid cells. Expression of other erythroid specific genes such as EKLF, GATA1 and GATA3 is unaltered in these animals. These findings demonstrate the LKLF function is indispensable during normal embryonic development, and although both LKLF and EKLF recognize common DNA motifs, they do not substitute for each other.


Asunto(s)
Muerte Fetal/genética , Muerte Fetal/fisiopatología , Transactivadores/genética , Transactivadores/fisiología , Animales , Secuencia de Bases , Cartilla de ADN/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/fisiología , Desarrollo Embrionario y Fetal/genética , Desarrollo Embrionario y Fetal/fisiología , Factores de Unión al ADN Específico de las Células Eritroides , Femenino , Factor de Transcripción GATA1 , Factor de Transcripción GATA3 , Regulación del Desarrollo de la Expresión Génica , Marcación de Gen , Hematopoyesis/genética , Hematopoyesis/fisiología , Factores de Transcripción de Tipo Kruppel , Pulmón/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fenotipo , Embarazo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Transcripción/genética , Factores de Transcripción/fisiología , Dedos de Zinc/genética , Dedos de Zinc/fisiología
12.
Clin Chem ; 44(1): 35-9, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9550555

RESUMEN

The concentration of soluble transferrin receptor (sTfR) in serum is reported to be useful in the diagnosis of iron deficiency, especially for patients with concurrent chronic disease, where routine tests of iron status are compromised by the inflammatory condition. A new diagnostic assay for sTfR is calibrated against natural plasma sTfR, thus minimizing calibration discrepancies that result from differences between the analyte and the cellular transferrin receptor used in other assays. Use of the new assay to measure sTfR concentrations in 225 healthy, hematologically normal adults provided a reference interval against which pathological samples could be compared. There was no difference in the reference intervals for men and women and no correlation of [sTfR] with the age of the subject. Black subjects had significantly higher concentrations than nonblacks, and people living at high altitude had higher concentrations than those living closer to sea level. These differences were additive.


Asunto(s)
Receptores de Transferrina/sangre , Factores de Edad , Altitud , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Posmenopausia/sangre , Premenopausia/sangre , Grupos Raciales , Valores de Referencia , Sensibilidad y Especificidad , Factores Sexuales , Solubilidad , Estados Unidos
13.
Clin Lab Haematol ; 19(2): 93-7, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9218147

RESUMEN

Serum transferrin receptor (sTfR) concentrations were measured in specimens from 77 patients undergoing serum ferritin determination, and the results correlated with serum ferritin, serum iron, serum total iron-binding capacity (TIBC) saturation, erythrocyte mean corpuscular volume (MCV), and mean corpuscular haemoglobin (MCH). All parameters exhibited the expected inverse correlation with sTfR; this correlation was statistically significant for all parameters except serum iron concentration. The frequency with which iron deficiency (defined as absence of stainable marrow iron) is observed in patients with particular ferritin values in this centre was determined and used to estimate the expected number of iron deficient patients in the present study. In no setting were significantly fewer sTfR levels > 3.05 micrograms/ml observed than expected. However, significantly greater than expected numbers of elevated sTfR values were observed in patients with serum ferritin > 220 micrograms/l (P = 0.002). The results suggest that the sTfR level is probably not useful as a single test for identification of iron deficiency in unselected patients.


Asunto(s)
Deficiencias de Hierro , Receptores de Transferrina/sangre , Receptores de Transferrina/metabolismo , Anemia/sangre , Anemia/complicaciones , Índices de Eritrocitos , Hemoglobinas/metabolismo , Humanos , Hierro/sangre , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/complicaciones , Reticulocitos/metabolismo , Enfermedades Reumáticas/complicaciones
15.
Cytokines Cell Mol Ther ; 3(3): 179-86, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9426976

RESUMEN

The anaemia that is a common complication of human immunodeficiency virus (HIV) infection bears many similarities to the anaemia of chronic disease. These similarities include an impaired erythropoietin (EPO) response to anaemia, reduced concentrations of marrow progenitors giving rise to erythroid colonies, abnormalities of reticuloendothelial iron metabolism, and correction of anaemia with recombinant human EPO. A model has been developed in which the pathophysiologic processes producing the anaemia of chronic disease may be attributed to actions of the cytokines that mediate the immune response, such as interleukin-1, tumor necrosis factor and the interferons. These cytokines are also implicated in HIV-related anaemia. In this review, the applicability of this cytokine-mediated anaemia model to the anaemia of HIV infection is explored.


Asunto(s)
Anemia/etiología , Citocinas/fisiología , Infecciones por VIH/complicaciones , Anemia/inmunología , Células Precursoras Eritroides , Eritropoyesis/fisiología , Eritropoyetina/metabolismo , Eritropoyetina/uso terapéutico , Humanos , Interferones/inmunología , Interferones/farmacología , Interferones/fisiología , Interleucina-1/inmunología , Interleucina-1/fisiología , Hierro/metabolismo , Factor de Necrosis Tumoral alfa/inmunología , Factor de Necrosis Tumoral alfa/fisiología
16.
Am J Hematol ; 53(2): 118-20, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8892737

RESUMEN

Increased production of cytokines such as beta-interferon (IFN) and gamma-IFN may contribute to the anemia frequently observed in patients with human immunodeficiency virus (HIV) infection. The hypothesis that HIV infection might enhance the susceptibility of erythroid progenitors to cytokine-mediated inhibition was evaluated by comparing the effects of beta- and gamma-IFN on in vitro colony formation by marrow erythroid colony-forming units (CFU-E) from HIV patients, normal volunteers, and anemic non-HIV-infected individuals. CFU-E colony formation from HIV patients was not significantly different from controls, and the degree of inhibition by IFN did not differ among patient subsets. HIV infection does not appear to impair baseline CFU-E colony formation, nor does it appear to enhance the susceptibility of CFU-E to suppression by cytokines.


Asunto(s)
Médula Ósea/patología , Infecciones por VIH/patología , Células Madre Hematopoyéticas/patología , Interferón beta/farmacología , Interferón gamma/farmacología , Anemia/patología , Células Cultivadas , Ensayo de Unidades Formadoras de Colonias , Humanos , Proteínas Recombinantes/farmacología
17.
AIDS ; 10(9): F29-33, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8853724

RESUMEN

OBJECTIVE: To evaluate serum chemokines, macrophage inflammatory protein (MIP)-1 alpha, MIP-1 beta and RANTES, concentrations in non-progressing HIV-infected patients and AIDS patients. SETTING: University Hospital-based AIDS Clinical Trials Unit. DESIGN/METHODS: Serum MIP-1 alpha, MIP-1 beta and RANTES levels were determined by enzyme-linked immunosorbent assay using archived serum specimens obtained on two occasions at least 1.8 years apart. PATIENT SELECTION: Long-term non-progressing HIV-infected adult patients were identified from clinic records. For each non-progressing patient two adult AIDS patients with initial documentation of seropositivity the same year and the same length of follow-up were selected. RESULTS: Four long-term non-progressing patients and eight AIDS patients were studied. Neither the duration of known HIV positivity at the time of specimen collection nor the length of time between specimen collections differed significantly between non-progressing patients and AIDS patients. Serum levels of MIP-1 alpha, MIP-1 beta and RANTES in specimens obtained either early or later in the course of HIV infection did not differ significantly between non-progressing patients and AIDS patients. In the two patient subsets, significant differences in serum chemokine levels over time were not observed. The rate of change of serum chemokine concentration over time also did not differ between non-progressing patients and AIDS patients. Serum MIP-1 alpha and MIP-1 beta levels did not reach levels reported to suppress HIV proliferation in vitro. When expressed as a quantity per peripheral blood CD8+ lymphocyte, AIDS patients exhibited significantly greater levels of MIP-1 alpha, MIP-1 beta and RANTES than non-progressing HIV patients (P < 0.05). These values did not exhibit a significant variation over time. CONCLUSIONS: Serum MIP-1 alpha, MIP-1 beta and RANTES levels do not distinguish patients with AIDS from patients with non-progressing HIV infection. Variations in levels of these chemokines do not explain individual variation in the natural history of HIV infection.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/sangre , Quimiocinas/sangre , Infecciones por VIH/sangre , VIH-1 , Adulto , Humanos , Persona de Mediana Edad
18.
Leukemia ; 10(6): 978-83, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8667655

RESUMEN

tif is a recently cloned and characterized cDNA predicting a transmembrane protein with a putative tyrosine kinase structure in its cytoplasmic domain. By analysis of the purified tif cytoplasmic domain expressed in Escherichia coli, we have demonstrated that tif is an active protein tyrosine kinase capable of autophosphorylation on tyrosine residues and this phosphorylation is inhibited by a tyrosine-specific inhibitor genistein. Northern blot analyses of various leukemia cell lines have revealed that tif mRNA expression is primarily confined to those bearing erythroid and megakaryocytic phenotypes. Megakaryocytic differentiation of K562 and HEL cells induced by phorbol 12-myristate 13-acetate is accompanied by down-regulation of tif mRNA expression. In addition, treatment of K562 and HEL with hexamethylene bis-acetamide, but not with hemin, decreases the steady-state level of tif mRNA. These combined results suggest that the receptor tyrosine kinase tif is involved in hematopoietic development.


Asunto(s)
Regulación Enzimológica de la Expresión Génica , Regulación Leucémica de la Expresión Génica , Leucemia/genética , Proteínas Tirosina Quinasas Receptoras/genética , Acetamidas/farmacología , Secuencia de Bases , Diferenciación Celular/efectos de los fármacos , Regulación hacia Abajo , Humanos , Leucemia/enzimología , Leucemia/patología , Leucemia Eritroblástica Aguda/enzimología , Leucemia Eritroblástica Aguda/genética , Leucemia Eritroblástica Aguda/patología , Leucemia Megacarioblástica Aguda/enzimología , Leucemia Megacarioblástica Aguda/genética , Leucemia Megacarioblástica Aguda/patología , Datos de Secuencia Molecular , Fosforilación , ARN Mensajero/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Acetato de Tetradecanoilforbol/farmacología , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/patología
19.
Alcohol Clin Exp Res ; 20(2): 355-8, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8801824

RESUMEN

PURPOSE: The anemia of chronic disease is mediated by the cytokines that modulate the immune response, such as tumor necrosis factor (TNF) and gamma-interferon (gamma-IFN), and is associated with a blunted serum erythropoietin (sEPO) response to anemia. Previous reports suggest that patients with liver disease (LD) also exhibit a blunted sEPO response to anemia, and that patients with alcoholic LD had altered cytokines, including elevated TNF levels. To investigate the pathogenesis of anemia in alcoholic LD, sEPO, TNF, and gamma-IFN levels were determined in patients who had participated in a Department of Veterans Affairs Cooperative study of alcoholic LD. METHODS: sEPO, serum TNF-alpha, and serum gamma-IFN levels were evaluated in 40 patients with severe biopsy-proven alcoholic LD whose serum had been stored during the Department of Veterans Affairs Cooperative Study 275, and in 18 patients with iron deficiency (controls). RESULTS: Mean hemoglobin (Hgb) was 11.2 +/- 0.3 g/dl for LD patients versus 11.4 +/- 0.4 g/dl for controls (p = 0.84). sEPO levels measured by ELISA were 29.6 +/- 4.1 units/liter in LD patients versus 25.4 +/- 5.4 units/liter in controls (p = 0.64). In both sets of patients, sEPO and Hgb were inversely related; the slopes of the two regression lines did not differ significantly (p = 0.92). TNF was detected in 3 of 40 LD patients and in 0 of 18 iron-deficient patients. Detection of TNF did not correlate with sEPO or Hgb, but did correlate strongly with severe caloric malnutrition (marasmus) and mortality at 6 months (p = 0.049 and 0.04, respectively). gamma-IFN was not detected. CONCLUSIONS: These findings indicate that the sEPO response is preserved in patients with severe alcoholic LD, and suggest that anemia in LD arises from different mechanisms than does the anemia of chronic disease. TNF production in severe alcoholic LD is strongly correlated with caloric malnutrition and mortality.


Asunto(s)
Anemia/sangre , Citocinas/sangre , Eritropoyetina/sangre , Hepatopatías Alcohólicas/sangre , Anemia/rehabilitación , Anemia Ferropénica/sangre , Anemia Ferropénica/rehabilitación , Terapia Combinada , Hemoglobinometría , Humanos , Hepatopatías Alcohólicas/rehabilitación , Estado Nutricional , Desnutrición Proteico-Calórica/sangre , Desnutrición Proteico-Calórica/rehabilitación , Valores de Referencia , Factor de Necrosis Tumoral alfa/metabolismo
20.
Exp Hematol ; 24(2): 204-8, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8641342

RESUMEN

Previous investigations have demonstrated that interferons alpha, beta, and gamma (alpha-, beta-, and gamma-IFN) are potent inhibitors of erythropoiesis in vitro. By utilizing a cell population enriched for human erythroid colony-forming units (CFU-E), we have previously demonstrated that the inhibitory effects of beta- and gamma-IFNs are direct effects, not requiring the presence of accessory cells, and that the inhibitory effect of recombinant human (rh) gamma-IFN could be corrected by high concentrations of rh erythropoietin (Epo). In this study, we compared the effects of rh(alpha)-IFN on cells enriched for CFU-E to its effects on unpurified marrow cells and found that although h(beta)-IFN (which shares a common receptor with alpha-IFN) directly inhibits CFU-E colony formation, the effect of rh(alpha)-IFN is indirect and is mediated by a soluble factor released from T lymphocytes in response to rh(alpha)-IFN. However, rh(alpha)-IFN enhanced the direct inhibitory effect of rh(gamma)-IFN on CFU-E not inhibited by rh(alpha)-IFN. The inhibitory effects of neither alpha- nor beta-IFN could be overcome by high levels of rhEpo. These findings imply that alpha- and beta-IFN exert different cellular effects despite binding to the same receptor. Failure of rhEpo to correct CFU-E colony inhibition by alpha- and beta-IFNs but not by gamma-IFN also suggests a mechanism for the differing degrees of response to different doses of rhEpo in patients with the anemia of chronic disease.


Asunto(s)
Células Precursoras Eritroides/efectos de los fármacos , Interferón Tipo I/farmacología , Interferón beta/farmacología , Linfocinas/fisiología , Receptores de Interferón/efectos de los fármacos , Linfocitos T/metabolismo , Anemia/fisiopatología , Células Sanguíneas/citología , Células de la Médula Ósea , Ensayo de Unidades Formadoras de Colonias , Depresión Química , Eritropoyetina/farmacología , Humanos , Interferón gamma/farmacología , Receptores de Interferón/fisiología , Proteínas Recombinantes , Transducción de Señal
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