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1.
J Pharmacol Exp Ther ; 374(3): 469-478, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32631869

RESUMEN

The complex pathophysiology of sickle cell anemia (SCA) involves intravascular hemolytic processes and recurrent vaso-occlusion, driven by chronic vascular inflammation, which result in the disease's severe clinical complications, including recurrent painful vaso-occlusive episodes. Hydroxyurea, the only drug frequently used for SCA therapy, is a cytostatic agent, although it appears to exert nitric oxide/soluble guanylyl cyclase (sGC) modulating activity. As new drugs that can complement or replace the use of hydroxyurea are sought to further reduce vaso-occlusive episode frequency in SCA, we investigated the effects of the sGC agonists BAY 60-2770 (sGC activator) and BAY 41-2272 (sGC stimulator) in the presence or absence of hydroxyurea on SCA vaso-occlusive mechanisms and cell recruitment both ex vivo and in vivo. These agents significantly reduced stimulated human SCA neutrophil adhesive properties ex vivo in association with the inhibition of surface ß2-integrin activation. A single administration of BAY 60-2770 or BAY 41-2272 decreased tumor necrosis factor cytokine-induced leukocyte recruitment in a mouse model of SCA vaso-occlusion. Importantly, the in vivo actions of both agonists were significantly potentiated by the coadministration of hydroxyurea. Erythroid cell fetal hemoglobin (HbF) elevation is also a major goal for SCA therapy. BAY 41-2272 but not BAY 60-2770 at the concentrations employed significantly induced γ-globin gene transcription in association with HbF production in cultured erythroleukemic cells. In conclusion, sGC agonist drugs could represent a promising approach as therapy for SCA, for use either as stand-alone treatments or in combination with hydroxyurea. SIGNIFICANCE STATEMENT: This preclinical study demonstrates that stimulators and activators of sGC are potent inhibitors of the adhesion and recruitment of leukocytes from humans and in mice with sickle cell anemia (SCA) and may represent a promising approach for diminishing vaso-occlusive episode frequency in SCA. Hydroxyurea, a drug already frequently used for treating SCA, was found to potentiate the beneficial effects of sGC agonists in in vivo studies, implying that these classes of compounds could be used alone or in combination therapy.


Asunto(s)
Anemia de Células Falciformes/tratamiento farmacológico , Anemia de Células Falciformes/metabolismo , Hidroxiurea/farmacocinética , Guanilil Ciclasa Soluble/metabolismo , Animales , Benzoatos/farmacología , Compuestos de Bifenilo/farmacología , Línea Celular Tumoral , Modelos Animales de Enfermedad , Células Eritroides/efectos de los fármacos , Células Eritroides/metabolismo , Hemoglobina Fetal/metabolismo , Humanos , Hidrocarburos Fluorados/farmacología , Células K562 , Masculino , Ratones , Ratones Endogámicos C57BL , Pirazoles/farmacología , Piridinas/farmacología , Enfermedades Vasculares/tratamiento farmacológico , Enfermedades Vasculares/metabolismo , Vasodilatadores/farmacología
2.
Ann Hematol ; 99(5): 955-962, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32266426

RESUMEN

Hereditary anemias are a group of heterogeneous disorders including hemolytic anemias and hyporegenerative anemias, as congenital dyserythropoietic anemia (CDA). Causative mutations occur in a wide range of genes leading to deficiencies in red cell production, structure, or function. The genetic screening of the main genes is important for timely diagnosis, since routine laboratory tests fail in a percentage of the cases, appropriate treatment decisions, and genetic counseling purposes. A conventional gene-by-gene sequencing approach is expensive and highly time-consuming, due to the genetic complexity of these diseases. To overcome this problem, we customized a targeted sequencing panel covering 35 genes previously associated to red cell disorders. We analyzed 36 patients, and potentially pathogenic variants were identified in 26 cases (72%). Twenty variants were novel. Remarkably, mutations in the SPTB gene (ß-spectrin) were found in 34.6% of the patients with hereditary spherocytosis (HS), suggesting that SPTB is a major HS gene in the Southeast of Brazil. We also identified two cases with dominant HS presenting null mutations in trans with α-LELY in SPTA1 gene. This is the first comprehensive genetic analysis for hereditary anemias in the Brazilian population, contributing to a better understanding of the genetic basis and phenotypic consequences of these rare conditions in our population.


Asunto(s)
Anemia Diseritropoyética Congénita/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Mutación , Espectrina/genética , Esferocitosis Hereditaria/genética , Brasil , Femenino , Humanos , Masculino
3.
Biochem Genet ; 58(4): 580-594, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32277314

RESUMEN

The impaired bioavailability of endogenous nitric oxide (NO) in sickle cell anemia (SCA) may be influenced by polymorphisms in the endothelial nitric oxide synthase gene (eNOS). We compared allelic/genotypic frequencies of the eNOS polymorphisms T-786C, VNTR4a/b and G894T between 89 adult SCA patients and 100 healthy controls, and investigated the relationship between these SNPs and markers of hemolysis [lactate dehydrogenase (LDH), indirect bilirubin (IB) and reticulocyte counts], inflammation [interleukins IL-1ß, IL-6, IL-8, Tumor Necrosis Factor (TNF-α) and C-reactive protein (CRP)] and endothelial dysfunction (ED) [soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble intercellular adhesion molecule-1 (sICAM-1), soluble L-selectin (sL-selectin), von Willebrand Factor (vWF) antigen and D-dimers] in the patients. The frequencies of the mutant -786C allele and -786C/C genotype were significantly higher in patients (p = 0.02 and p = 0.04, respectively) but not significantly correlated with the markers. For VNTR4a/b and G894T, the allelic/genotypic frequencies did not statistically differ between patient and control groups. Patients carrying the 4a allele and those with the 894G/G genotype showed a significant decrease in IB (p = 0.02 and p = 0.04, respectively), and only patients with the 4a allele exhibited reduced IL-1ß (p = 0.01). The correlation profiles between markers of inflammation and ED significantly differed between patients carrying the mutant alleles and those with wild-type genotypes. This appears to be the first report on the relationship between eNOS gene polymorphisms and markers of hemolysis, inflammation and ED in Brazilian SCA patients. Our results indicate that the SNPs analyzed may influence the phenotypic variability of these patients.


Asunto(s)
Anemia de Células Falciformes/enzimología , Anemia de Células Falciformes/genética , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Hemólisis , Molécula 1 de Adhesión Intercelular/sangre , Óxido Nítrico Sintasa de Tipo III/genética , Polimorfismo de Nucleótido Simple , Molécula 1 de Adhesión Celular Vascular/sangre , Factor de von Willebrand/análisis , Adulto , Alelos , Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/epidemiología , Bilirrubina/sangre , Biomarcadores/sangre , Brasil/epidemiología , Estudios de Casos y Controles , Citocinas/sangre , Femenino , Frecuencia de los Genes , Haplotipos , Humanos , Inflamación/sangre , L-Lactato Deshidrogenasa/sangre , Masculino , Recuento de Reticulocitos , Adulto Joven
4.
Int Endod J ; 52(4): 400-406, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30284719

RESUMEN

AIM: To evaluate the frequency of post-treatment apical periodontitis associated with root filled teeth with at least one untreated root canal. METHODOLOGY: Eight hundred and seven cone beam computed tomography images containing at least one root filled tooth were selected from a collection of 1543 images from Brazilian individuals. Scans were taken using ICAT Classic devices (Imaging Sciences, Hatfield, PA, USA) in a private oral radiology clinic from January to April 2015. All root filled teeth were analysed for the presence of missed canals and apical periodontitis. The chi-square and odds ratio tests were used to verify if there were an association and risk relationship between the occurrence of untreated canals and apical periodontitis. RESULTS: A total of 2294 teeth with evidence of root fillings were identified. Two hundred and eighty-one teeth had at least one untreated missed canal (12%). The frequency of apical periodontitis in teeth with at least one untreated canal was significantly greater in comparison to teeth with all canals treated (274/281, 98% versus 1736/2013, 86%) (P < 0.01). The odds for apical periodontitis to be present was 6.25 times greater for teeth with an untreated canal. The mesiobuccal roots of maxillary first molars had the greatest frequency of untreated canals (114/154, 74%), with the second mesiobuccal canal being the most frequently missed (n = 106/114, 93%). CONCLUSION: Root filled teeth with at least one missed canal had a high prevalence of post-treatment apical periodontitis.


Asunto(s)
Periodontitis Periapical , Brasil , Cavidad Pulpar , Humanos , Obturación del Conducto Radicular , Raíz del Diente
5.
Arch Biochem Biophys ; 637: 73-78, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29199120

RESUMEN

Human hemoglobin (Hb) Coimbra (ßAsp99Glu) is one of the seven ßAsp99 Hb variants described to date. All ßAsp99 substitutions result in increased affinity for O2 and decreased heme-heme cooperativity and their carriers are clinically characterized by erythrocytocis, caused by tissue hypoxia. Since ßAsp99 plays an important role in the allosteric α1ß2 interface and the mutation in Hb Coimbra only represents the insertion of a CH2 group in this interface, the present study of Hb Coimbra is important for a better understanding of the global impact of small modifications in this allosteric interface. We carried out functional, kinetic and dynamic characterization of this hemoglobin, focusing on the interpretation of these results in the context of a growth of the position 99 side chain length in the α1ß2 interface. Oxygen affinity was evaluated by measuring p50 values in distinct pHs (Bohr effect), and the heme-heme cooperativity was analyzed by determining the Hill coefficient (n), in addition to the effect of the allosteric effectors inositol hexaphosphate (IHP) and 2,3-bisphosphoglyceric acid (2,3-BPG). Computer simulations revealed a stabilization of the R state in the Coimbra variant with respect to the wild type, and consistently, the T-to-R quaternary transition was observed on the nanosecond time scale of classical molecular dynamics simulations.


Asunto(s)
Hemoglobinas Anormales/química , Hemoglobinas Anormales/metabolismo , 2,3-Difosfoglicerato/farmacología , Regulación Alostérica , Hemo/metabolismo , Hemoglobinas Anormales/genética , Humanos , Técnicas In Vitro , Cinética , Modelos Moleculares , Simulación de Dinámica Molecular , Oxígeno/metabolismo , Ácido Fítico/farmacología , Dominios y Motivos de Interacción de Proteínas , Estructura Cuaternaria de Proteína
6.
Niger J Clin Pract ; 21(7): 882-887, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29984720

RESUMEN

BACKGROUND: Sickle leg ulcer (SLU) is a chronic and debilitating complication of sickle cell disease (SCD) associated with huge physical and psychosocial discomfort. The occurrence of SLU has remained steady despite successful preventive strategies and advances in SCD care. Although multifactorial factors have been implicated in SLU, these are not fully understood, and data on how these relate to young Nigerian SCD patients are scanty. AIMS: This study aims to evaluate the sociodemographic, clinical, and laboratory markers of SLU in a young Nigerian SCD cohort. PATIENTS AND METHODS: This study involved 109 young SCD patients and 67 healthy peers. The sociodemographic and laboratory parameters of the participants were examined in addition to the evaluation of the SCD cohort for SLU. RESULTS: Only the HbSS patients had SLU. This was found in six of them giving a prevalence of 5.9% (6/101). Their median age was 17, range 14-21 years. There was a preceding history of trauma in 4 (66.7%), and this included a case of traditional scarifications for local therapeutic purposes. Two of the three (66.7%) males with SLU also had priapism (P = 0.0132). Patients with SLU were older, had less frequent bone pain crises, and significantly belonged to the low socioeconomic class (P < 0.05). Although patients with SLU had relatively higher lactate dehydrogenase, platelet count, aspartate transaminase, bilirubin, white blood cell, and lower Hb concentration and HbF, these did not attain statistical significance (P > 0.05). CONCLUSION: This study confirms that SLU is common among young SCD patients with HbSS genotype, low socioeconomic background, and older age. It also suggests that SLU could be more related to hemolysis-associated SCD phenotypes among the patients.


Asunto(s)
Anemia de Células Falciformes/complicaciones , Bilirrubina/sangre , Población Negra/estadística & datos numéricos , Úlcera de la Pierna/etiología , Adolescente , Adulto , Anciano , Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/epidemiología , Biomarcadores , Estudios de Cohortes , Femenino , Humanos , Úlcera de la Pierna/sangre , Úlcera de la Pierna/epidemiología , Masculino , Persona de Mediana Edad , Nigeria/epidemiología , Recuento de Plaquetas , Prevalencia , Priapismo , Índice de Severidad de la Enfermedad , Factores Socioeconómicos , Adulto Joven
7.
Blood Cells Mol Dis ; 54(1): 33-7, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25172543

RESUMEN

Sickle cell retinopathy (SCR) develops in up to 30% of sickle cell disease patients (SCD) during the second decade of life. Treatment for this affection remains palliative, so studies on its pathophysiology may contribute to the future development of novel therapies. SCR is more frequently observed in hemoglobin SC disease and derives from vaso-occlusion in the microvasculature of the retina leading to neovascularization and, eventually, to blindness. Circulating inflammatory cytokines, angiogenic factors, and their interaction may contribute to the pathophysiology of this complication. Angiopoietin (Ang)-1, Ang-2, soluble vascular cell adhesion molecule-1, intercellular adhesion molecule (ICAM)-1, E-selectin, P-selectin, IL1-ß, TNF-α, pigment epithelium derived factor (PEDF) and vascular endothelial growth factor plasmatic levels were determined in 37 SCD patients with retinopathy, 34 without retinopathy, and healthy controls. We observed that sICAM-1 is significantly decreased, whereas PEDF is elevated in HbSC patients with retinopathy (P=0.012 and P=0.031, respectively). Ang-1, Ang-2 and IL1-ß levels were elevated in SCD patients (P=0.001, P<0.001 and P=0.001, respectively), compared to controls, and HbSS patients presented higher levels of Ang-2 compared to HbSC (P<0.001). Our study supports the possible influence of sICAM-1 and PEDF on the pathophysiology of retinal neovascularization in SCD patients.


Asunto(s)
Anemia de Células Falciformes/sangre , Proteínas del Ojo/sangre , Molécula 1 de Adhesión Intercelular/sangre , Factores de Crecimiento Nervioso/sangre , Neovascularización Retiniana/sangre , Serpinas/sangre , Adulto , Anemia de Células Falciformes/complicaciones , Angiopoyetina 1/sangre , Angiopoyetina 2/sangre , Estudios de Casos y Controles , Femenino , Humanos , Interleucina-1beta/sangre , Masculino , Persona de Mediana Edad , Neovascularización Retiniana/etiología , Factor de Necrosis Tumoral alfa/sangre
8.
J Hum Nutr Diet ; 28 Suppl 1: 65-72, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24480047

RESUMEN

BACKGROUND: The Consumo Alimentar e Atividade Fisica de Escolares (CAAFE) questionnaire is an online research tool that has been developed to enable the self-report of physical activity and diet by Brazilian schoolchildren aged 7-10 years. Formative research was conducted with nutritionists during the development of the web-based questionnaire. The suggestions and insights obtained were used to design a tool to monitor schoolchildren's food consumption based on the concept of healthy and unhealthy food indicators. The present study aimed to report the focus group discussions conducted with nutritionists concerning the CAAFE questionnaire. METHODS: Focus group discussions were conducted using a semi-structured questionnaire, and these were then analysed thematically. RESULTS: Twenty-four nutritionists participated (four focus groups; average per group: six people); the majority (n = 22) had experience with 7-10-year-old children. Four themes emerged: (i) healthy and unhealthy food indicators; (ii) suggestions for the online instrument; (iii) potential applications; and (iv) challenges for its construction. CONCLUSIONS: Comments made by nutritionists enabled the construction of an instrument that is able to answer questions related to food consumption in schools and at home.


Asunto(s)
Dieta , Conducta Alimentaria , Evaluación Nutricional , Nutricionistas , Encuestas y Cuestionarios , Adulto , Brasil , Niño , Grupos Focales , Humanos , Internet , Masculino , Persona de Mediana Edad , Competencia Profesional , Investigación Cualitativa
11.
Neoplasma ; 59(5): 530-5, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22668018

RESUMEN

MDM2/p53 pathway plays an important role in the control of apoptotic and proliferation mechanisms, and alterations in this pathway have been described in myelodysplastic syndromes (MDS). We investigated the frequency of MDM2 SNP309, TP53 Arg72Pro polymorphisms in de novo MDS and the association of these polymorphisms with clinical characteristics. Our results showed that the frequencies of genotypes for MDM2 SNP309 and TP53 Arg72Pro did not differ between MDS and healthy controls and that these polymorphisms were not associated with clinical and laboratory parameters, disease progression and overall survival, suggesting that MDM2 and TP53 polymorphisms are not involved in risk for MDS, or in the clinical and laboratory characteristics of the disease.


Asunto(s)
Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/mortalidad , Polimorfismo de Nucleótido Simple/genética , Proteínas Proto-Oncogénicas c-mdm2/genética , Proteína p53 Supresora de Tumor/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , ADN de Neoplasias/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/patología , Estadificación de Neoplasias , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Pronóstico , Tasa de Supervivencia , Adulto Joven
12.
Genet Mol Res ; 11(4): 3861-8, 2012 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-23212325

RESUMEN

Phosphatidylinositol phosphate kinases (PIPKs) are enzymes that participate in diverse intracellular signaling pathways. They are classified into 3 functionally distinct subfamilies - PIPKI (α, ß, γ), PIPKII (α, ß, γ), and PIPKIII - located in various subcellular compartments. Recently, the PIPKIIα and ß-globin genes were found to be overexpressed in reticulocytes from 2 siblings with hemoglobin H disease, suggesting a possible relationship between PIPKIIa and the production of globins. The main aim of this study was to determine the expression profiles of PIPK genes in healthy individuals during in vitro erythropoiesis using quantitative real-time polymerase chain reaction and to compare these profiles with profiles of globin genes. Our results showed that expression of all PIPKs increases as the cells differentiate, coinciding with the expression profiles of globins. Analysis of the effects of globins on PIPK genes revealed that they varied significantly between the globins, the most noticeable being the effect of α-globin on PIPKIIα (P < 0.0001) and γ-globin on PIPKIIγ (P < 0.0001). The relationship between the expression of PIPKs and globin genes was statistically significant, particularly between PIPKIIα and α-globin (P = 0.0002) and PIPKIIγ and ß-globin (P < 0.0001). Linear correlation analysis revealed a strong relationship between PIPKIIα and α-globin genes. This study is the first to establish the expression profiles of PIPK genes during in vitro erythropoiesis in healthy individuals and suggests a parallel between the expression of PIPK and globin genes, reinforcing the hypothesis that they may be related.


Asunto(s)
Eritropoyesis/genética , Perfilación de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Adulto , Área Bajo la Curva , Globinas/genética , Globinas/metabolismo , Humanos , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo
13.
Scand J Immunol ; 73(4): 309-18, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21208248

RESUMEN

Neutrophils participate in the initiation and progression of rheumatoid arthritis (RA) although the exact mechanisms responsible for neutrophil accumulation in rheumatoid joints are not understood. This study compared the adhesive and chemotactic functions of neutrophils from RA patients in activity (DAS28 > 3.2) and not in activity (DAS28 < 2.6) and observed the effects of different treatment approaches on these functions. Neutrophils were isolated from healthy controls (CON), and patients with active or inactive RA in use of therapy not specific for RA (NSAIDs), in use of DMARDs and in use of anti-TNF-α therapy. Adhesive and chemotactic properties were evaluated using in vitro assays; adhesion molecule expression was assessed by flow cytometry and real-time PCR and circulating chemokines were determined by ELISA. No significant alterations in the adhesive and chemotactic properties of neutrophils from active RA were observed when compared to CON neutrophils, independently of treatment regimen. In contrast, neutrophils from RA patients in disease remission presented reduced adhesive properties and a lower spontaneous chemotactic capacity, in association with decreased adhesion molecule expression, although profiles of alterations differed for those patients on DMARDs and those on anti-TNF-α therapy. Circulating levels of the major neutrophilic chemokines, IL-8 and epithelial neutrophil activating peptide-78, were also significantly decreased in those patients demonstrating a clinical response. Remission of RA appears to be associated with ameliorations in aspects important for neutrophil adhesion and chemotaxis; whether these alterations contribute to decrease neutrophil migration to the synovial fluid, with consequent improvements in the clinical manifestations of RA, remains to be determined.


Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Quimiocinas/sangre , Quimiotaxis de Leucocito/efectos de los fármacos , Neutrófilos/citología , Neutrófilos/efectos de los fármacos , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Adulto , Anciano , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Antirreumáticos/farmacología , Antirreumáticos/uso terapéutico , Artritis Reumatoide/sangre , Artritis Reumatoide/diagnóstico , Estudios de Casos y Controles , Adhesión Celular/efectos de los fármacos , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/metabolismo , Femenino , Expresión Génica/efectos de los fármacos , Humanos , Infliximab , Interleucina-8/sangre , Interleucina-8/farmacología , Selectina L/sangre , Masculino , Persona de Mediana Edad , Neutrófilos/metabolismo , Inducción de Remisión , Adulto Joven
14.
Bull Entomol Res ; 101(4): 383-91, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21205397

RESUMEN

The lower termite, Coptotermes gestroi (Isoptera: Rhinotermitidae), is originally from Southeast Asia and has become a pest in Brazil. The main goal of this study was to survey C. gestroi transcriptome composition. To accomplish this, we sequenced and analyzed 3003 expressed sequence tags (ESTs) isolated from libraries of worker heads. After assembly, 695 uniESTs were obtained from which 349 have similarity with known sequences. Comparison with insect genomes demonstrated similarity, primarily with genes from Apis mellifera (28%), Tribolium castaneum (28%) and Aedes aegypti (10%). Notably, we identified two endogenous cellulases in the sequences, which may be of interest for biotechnological applications. The results presented in this work represent the first genomic study of the Asian subterranean termite, Coptotermes gestroi.


Asunto(s)
Celulasas/aislamiento & purificación , Perfilación de la Expresión Génica , Isópteros/enzimología , Secuencia de Aminoácidos , Animales , Etiquetas de Secuencia Expresada , Biblioteca de Genes , Genoma de los Insectos , Cabeza , Isópteros/genética , Estadios del Ciclo de Vida , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido
15.
Vox Sang ; 98(2): 160-6, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19695014

RESUMEN

BACKGROUND AND OBJECTIVES: The human neutrophil antigen-2 (HNA-2) is expressed on a subpopulation of neutrophils as most subjects present a negative plus a positive HNA-2 population of neutrophils. The number of neutrophils expressing HNA-2 is variable and may increase in pregnancy, infections, myeloproliferative disorders and after G-CSF. This study investigated the presence of polymorphisms in the gene encoding HNA-2 (CD177) in individuals presenting different patterns of antigen expression and determined the association of single nucleotide polymorphisms (SNPs) with the heterogeneous HNA-2 expression. MATERIALS AND METHODS: Flow cytometry was employed to analyse the HNA-2 expression on neutrophils from 135 healthy subjects using two monoclonal antibodies (TAG4, 7D8). Sequencing reactions were performed on subjects whose antigen expression was low (< or = 50%), high (> or = 80%) or atypical (a nonreactive population plus two distinct positive cell populations). RESULTS: Five SNPs were detected, two of them (A793C, G1084A) were related to a low expression of HNA-2 (P = 0.031 and P = 0.004). Atypical antigen expression was observed in 5.9% (8/135) of the individuals, three nonpregnant women and five men. In these cases, the cDNA sequences revealed three SNPs (A134T, G156A and G1333A) strongly related to this atypical HNA-2 expression (P = 0.004, P = 0.006 and P < 0.0001, respectively). CONCLUSIONS: Our data show that polymorphisms in the CD177 are associated with variations in the HNA-2 expression and may be the cause of atypical expressions.


Asunto(s)
Isoantígenos/genética , Glicoproteínas de Membrana/genética , Neutrófilos/inmunología , Receptores de Superficie Celular/genética , Adulto , Femenino , Citometría de Flujo , Proteínas Ligadas a GPI , Humanos , Isoantígenos/biosíntesis , Isoantígenos/sangre , Isoantígenos/inmunología , Masculino , Glicoproteínas de Membrana/biosíntesis , Glicoproteínas de Membrana/sangre , Glicoproteínas de Membrana/inmunología , Persona de Mediana Edad , Neutrófilos/metabolismo , Polimorfismo de Nucleótido Simple , Receptores de Superficie Celular/biosíntesis , Receptores de Superficie Celular/sangre , Receptores de Superficie Celular/inmunología , Adulto Joven
16.
J Leukoc Biol ; 85(2): 235-42, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19004988

RESUMEN

Inflammation, cell adhesion to vascular endothelium, and endothelial injury contribute to sickle cell anemia (SCA) vaso-occlusion. Although alterations in inflammatory cytokines and biomarkers have been related, reports have been conflicting, and a conclusive role for these molecules in the disease remains to be established. Furthermore, the effect of hydroxyurea therapy (HU) on the release of inflammatory mediators is not understood. This study aimed to determine plasma levels and leukocyte gene expressions of inflammatory mediators in healthy controls, steady-state SCA patients, and SCA patients on HU therapy. TNF-alpha, IL-8, and PGE(2) levels were significantly higher in the plasma of SCA individuals when compared with control individuals. HU therapy was associated with a significant reversal of augmented TNF-alpha and, interestingly, increased plasma anti-inflammatory IL-10. IFN-gamma, IL-10, cyclooxygenase 2 (COX-2), and inducible NO synthase (iNOS) gene expressions were unaltered in SCA mononuclear cells (MC); however, gene expressions of TNF-alpha, IL-8, and the protective enzyme heme oxygenase-1 (HO-1) were significantly higher. HU therapy was not associated with significantly altered SCA MC inflammatory gene expression, although COX-2 mRNA expression was decreased. In SCA neutrophils, gene expressions of IL-8, IFN-gamma, iNOS, and HO-1 were significantly higher than those of control subjects. Patients on HU demonstrated lower iNOS and higher IL-10 neutrophil gene expressions. Taken together, data suggest that alterations in the gene expressions and productions of a number of pro- and anti-inflammatory mediators are present in SCA and importantly, in those patients on HU therapy. Knowledge of these pathways may contribute to further the understanding of the pathophysiology of this disease.


Asunto(s)
Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/tratamiento farmacológico , Citocinas/sangre , Hidroxiurea/uso terapéutico , Mediadores de Inflamación/sangre , Leucocitos/metabolismo , Adulto , Anemia de Células Falciformes/genética , Estudios de Casos y Controles , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Hidroxiurea/farmacología , Leucocitos/efectos de los fármacos , Masculino , Persona de Mediana Edad , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo
17.
Public Health Nutr ; 13(8): 1191-7, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20074387

RESUMEN

OBJECTIVE: There are few studies regarding vitamin B12 deficiency in developing countries. In Brazil, a late diagnosis of vitamin B12 deficiency progressing to severe neurological damage is common. Thus, the aim of the present study was to verify the frequency of vitamin B12 deficiency in two Brazilian populations (elderly and adult participants) and to compare different methods of vitamin B12 deficiency detection. DESIGN: Five hundred participants were recruited from health centres from south-east Brazil and were separated into two groups: 60 years old or more and 30-59 years old. Vitamin B12 and folate concentrations were measured using electrochemiluminescence immunoassay (ECI) and RIA. Methylmalonic acid (MMA) was measured by LC coupled to tandem MS. Full blood counts were acquired using standard methods. RESULTS: All participants had normal blood count results and mean cell volume less than 99 fl; none of them presented folate deficiency according to the results, which were all greater than 3 ng/ml. Cobalamin levels less than 200 pmol/l were identified by one of the two or by both methods in 7.2 % of the participants aged 60 years or more and 6.4 % of the participants aged 30-59 years. MMA levels were higher in older subjects (P = 0.007) compared with younger subjects. A greater correlation of MMA v. RIA was observed than of MMA v. ECI (P = 0.0017 v. P = 0.014). MMA quantification estimated that cobalamin deficiency was present in more than 11 % of the subjects for both studied groups. CONCLUSIONS: The study shows that vitamin B12 deficiency is frequent in Brazilian adults and suggests that RIA is more sensitive than ECl for measuring cobalamin levels.


Asunto(s)
Ácido Metilmalónico/sangre , Deficiencia de Vitamina B 12/epidemiología , Vitamina B 12/sangre , Adulto , Factores de Edad , Anciano , Brasil/epidemiología , Humanos , Inmunoensayo/métodos , Persona de Mediana Edad , Prevalencia , Deficiencia de Vitamina B 12/sangre , Deficiencia de Vitamina B 12/diagnóstico
18.
Vox Sang ; 97(2): 147-52, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19392786

RESUMEN

BACKGROUND: Blood samples from patients with sickle cell disease (SCD) present to transfusion service with numerous antibodies, making the searching for compatible red blood cells (RBC) a challenge. To overcome this problem we developed an effective strategy to meet needs of supplying RBC-compatible units to SCD patients using DNA arrays. METHODS: We selected DNA samples from 144 SCD patients with multiple (receiving > 5 units) transfusions previously phenotyped for ABO, Rh(D, C, c, E, e), K1, Fy(a) and Jk(a). We also selected DNA samples from 948 Brazilian blood donors whose ABO/RhD phenotype matched that of the patients. All samples were analysed by DNA array analysis (HEA Beadchip(TM), Bioarray Solutions) to determine polymorphisms associated with antigen expression for 11 blood group systems (Rh, Kell, Kidd, Duffy, MNS, Dombrock, Lutheran, Landsteiner-Wiener, Diego, Colton, Scianna); and one mutation associated with haemoglobinopathies. RESULTS: Based on genotype results we were able to predict phenotype-compatible donors needed in order to provide compatible units to this group of patients. Based on their ABO/Rh phenotype we were able to find in this pool of donors compatible units for 134 SCD patients. CONCLUSION: Blood group genotyping by DNA array contributes to the management of transfusions in SCD patients by facilitating the transfusion support with antigen-matched blood. It has the potential to improve the life of thousands of SCD-transfused patients by reducing mortality due to transfusion reactions and immunization.


Asunto(s)
Anemia de Células Falciformes/terapia , Antígenos de Grupos Sanguíneos/genética , Transfusión Sanguínea/métodos , Eritrocitos/inmunología , Isoantígenos/genética , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Antígenos de Grupos Sanguíneos/análisis , Brasil , Estudios de Casos y Controles , Genotipo , Humanos , Inmunofenotipificación , Isoantígenos/sangre
20.
Acta Haematol ; 120(4): 225-31, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19218790

RESUMEN

OBJECTIVE: The aim of this investigation was to study the effect of vitamin E treatment in oxidative stress of red and white cells of beta-thalassaemia intermedia patients. METHODS: Nine patients undergoing occasional transfusions (5 females/4 males), median age 39 years (range 15-74), were recruited for oral daily administration of 400 IU vitamin E for 3 months. Twenty-seven milliliters of peripheral blood was obtained before and after 3 months of treatment, and 3 months after treatment completion. In the case of transfused patients (n = 4), blood was obtained at least 30 days after transfusion. Reactive oxygen species (ROS) was measured by flow cytometry; red blood cell (RBC) reduced glutathione (GSH) was measured by dinitrothiocyanobenzene reduction, serum malondialdehyde was measured in terms of thiobarbituric acid-reactive substances (TBARS), and alpha-haemoglobin-stabilizing protein (AHSP) mRNA expression was measured by real-time polymerase chain reaction of reticulocyte RNA extracts. RESULTS: beta-Thalassaemia patients presented basal levels of RBC ROS, GSH and serum TBARS statistically different compared with healthy controls. However, after vitamin E administration, patients presented a significant reduction in erythrocyte RBC ROS and serum TBARS levels. In parallel, red cell GSH was significantly increased after treatment. Peripheral mononuclear cells and T lymphocytes also demonstrated a reduction in ROS production. Therefore, after treatment, no significant differences were detected comparing patients and normal controls. Three months after treatment completion, all measurements showed a tendency of returning to basal values. A significant reduction in reticulocyte number was observed after vitamin E treatment. Vitamin E treatment did not modify levels of haemoglobin or AHSP mRNA expression. CONCLUSION: Although vitamin E is not capable of reducing anaemia in these patients, it could be useful for reducing oxidative damage in other target organs of beta-thalassaemic patients. Finally, this is the first study to analyse the effects of vitamin E on ROS production in red and white blood cells and AHSP mRNA expression.


Asunto(s)
Antioxidantes/uso terapéutico , Vitamina E/uso terapéutico , Talasemia beta/tratamiento farmacológico , Talasemia beta/fisiopatología , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo
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