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1.
Vox Sang ; 112(3): 249-256, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28198023

RESUMO

BACKGROUND: Amotosalen/UVA-treated platelet concentrates (PCs) have demonstrated efficacy for treating and preventing bleeding in clinical trials and in routine use; however, most studies were performed in haematology/oncology patients. We investigated efficacy during massive transfusion (MT) in general hospitalized patients. METHODS: Universal amotosalen/UVA treatment (INTERCEPT Blood System) of platelets was introduced at a large Austrian medical centre. We performed a retrospective cohort analysis comparing component use, in-hospital mortality and length of stay after MT that included platelet transfusion, for two periods (21 months each) before and after implementation. RESULTS: A total of 306 patients had MT. Patients were mostly male (74%) and ≥18 years old (99%), including 93 liver transplant, 97 cardiac or vascular surgery and 51 trauma patients. There were no differences in demographics between the periods. Component use on the day and within 7 days of the MT event was unchanged post-IBS implementation, except trauma patients received fewer RBCs on the day. The mean ratio of RBC:platelets:plasma on the day of the MT was close to 1:1:1 in both periods, except for liver transplants with MT who received more plasma components. Overall, in-hospital mortality (preimplementation = 27·6% vs. postimplementation = 24·0%; P = 0·51) and median time to discharge (preimplementation = 27 vs. postimplementation = 23 days; P = 0·37) did not change, except for cardiac and vascular surgery patients who were discharged earlier. CONCLUSION: The introduction of amotosalen/UVA-treated, pathogen-reduced PC did not adversely affect clinical outcomes in massively transfused patients in terms of blood product usage, in-hospital mortality and length of stay for a range of clinical indications for platelet transfusion support.


Assuntos
Plaquetas/efeitos dos fármacos , Furocumarinas/farmacologia , Transfusão de Plaquetas , Raios Ultravioleta , Adolescente , Adulto , Idoso , Áustria , Plaquetas/metabolismo , Plaquetas/efeitos da radiação , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/cirurgia , Criança , Pré-Escolar , Feminino , Mortalidade Hospitalar , Hospitais , Humanos , Lactente , Estimativa de Kaplan-Meier , Tempo de Internação , Hepatopatias/mortalidade , Hepatopatias/terapia , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Ferimentos e Lesões/mortalidade , Ferimentos e Lesões/patologia , Adulto Jovem
2.
Vox Sang ; 112(1): 47-55, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28001297

RESUMO

BACKGROUND: In clinical studies, pathogen inactivation (PI) of platelet concentrates (PC) with amotosalen and UVA light did not impact patient risk for haemorrhage but may affect transfusion frequency and component utilization. We evaluated the influence of platelet PI on PC, red cell concentrate (RCC) and plasma use and safety in routine practice in a large regional hospital. STUDY DESIGN AND METHODS: Comparative effectiveness of conventional vs. PI-treated PC was analysed during two 21-month periods, before and after PI implementation. RESULTS: Similar numbers of patients were transfused in the pre-PI (control, 1797) and post-PI (test, 1694) periods with comparable numbers of PC (8611 and 7705, respectively). The mean numbers of PC per patient transfused (4·8 vs. 4·5, P = 0·43) were not different but days of PC support (5·9 vs. 5·0, P < 0·01) decreased. Most patients received RCC (86·8% control vs. 84·8% test, P = 0·90) with similar mean numbers transfused (10·8 vs. 10·2 RCC, P = 0·22), and fewer patients (55·4% control vs. 44·7% test, P < 0·01) received less plasma units (mean 9·9 vs. 7·8, respectively, P < 0·01) in the test period. The frequencies of transfusion-related adverse events (AE) were comparable (1·3% vs. 1·4%, P = 0·95). Analysis of haematology-oncology (522 control, 452 test), cardiac surgery (739 control, 711 test), paediatric (157 control, 130 test) and neonate (23 control, 20 test) patients revealed no increase in PC, plasma and RCC utilization, or AE. CONCLUSION: Component utilization and patient safety were not impacted by adoption of PI for PC. RCC use per patient was comparable, suggestive of no increase in significant bleeding.


Assuntos
Transfusão de Componentes Sanguíneos/efeitos adversos , Plaquetas/citologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Áustria , Plaquetas/efeitos dos fármacos , Plaquetas/efeitos da radiação , Criança , Pré-Escolar , Estudos de Coortes , Transfusão de Eritrócitos/efeitos adversos , Feminino , Furocumarinas/farmacologia , Hospitais , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Transfusão de Plaquetas/efeitos adversos , Fatores de Tempo , Raios Ultravioleta , Inativação de Vírus/efeitos dos fármacos , Inativação de Vírus/efeitos da radiação , Adulto Jovem
3.
Vox Sang ; 109(2): 114-21, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25899479

RESUMO

BACKGROUND: Mandatory screening of blood donations for hepatitis B and hepatitis C viruses and human immunodeficiency viruses 1 and 2 requires assays with exceptional sensitivity and specificity. This study reports the results from a direct head-to-head comparison of the Elecsys HBsAG II, Elecsys Anti-HBc, Elecsys Anti-HCV II and Elecsys HIV combi PT immunoassays with the respective ABBOTT PRISM/Architect instrument immunoassays in a multicentre blood bank evaluation study. STUDY DESIGN AND METHODS: Assay validation was performed in the blood screening laboratories of four blood bank centres in Austria, Germany, Spain and Thailand, where both first-time donor samples (approximately 6000 donors) and repeat donor samples (approximately 14,000 donors) were screened. RESULTS: Of all screened donor samples, 93 (0.46%) were confirmed to be positive using assays from both manufacturers. The specificity of all immunoassays was >99.5% and was comparable between first-time and multiple-time donors. A direct comparison between the assays from Roche and ABBOTT according to Bland and Altman analysis demonstrated equivalent quality. CONCLUSIONS: These results suggest that the Elecsys immunoassays for HBV, HCV and HIV infection, with a comparative sensitivity of 100% and a specificity exceeding the common technical specification threshold of >99.5%, meet the stringent performance criteria stipulated for blood donor screening for these infectious agents. Significant differences in the specificity between first-time and repeat donors were not detectable.


Assuntos
Infecções por HIV/sangue , Hepatite B/sangue , Hepatite C/sangue , Imunoensaio/métodos , Testes Sorológicos/métodos , Anticorpos Anti-HIV/sangue , Anticorpos Anti-HIV/imunologia , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/imunologia , Anticorpos Anti-Hepatite C/sangue , Anticorpos Anti-Hepatite C/imunologia , Humanos
4.
Med Microbiol Immunol ; 202(1): 77-86, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22706797

RESUMO

Education and diagnostic tests capable of early detection represent our most effective means of preventing transmission of human immunodeficiency virus (HIV). The importance of early detection is underlined by studies demonstrating increased life expectancy following early initiation of antiviral treatment. The Elecsys(®) HIV combi PT assay is a fourth-generation antigen-antibody combination assay developed to allow earlier detection of seroconversion, and to have increased sensitivity and improved specificity. We aimed to determine how early the assay could detect infection compared with existing assays; whether all HIV variants could be detected; and the assay's specificity using samples from blood donors, routine specimens, and patients with potential cross-reacting factors. Samples were identified as positive by the Elecsys(®) assay 4.9 days after a positive polymerase chain reaction result (as determined by the panel supplier), which was earlier than the 5.3-7.1 days observed with comparators. The analytical sensitivity of the Elecsys(®) HIV combi PT assay for the HIV-1 p24 antigen was 1.05 IU/mL, which compares favorably with the comparator assays. In addition, the Elecsys(®) assay identified all screened HIV subtypes and displayed greater sensitivity to HIV-2 homologous antigen and antibodies to HIV-1 E and O and HIV-2 than the other assays. Overall, the specificity of the Elecsys(®) assay was 99.88 % using samples from blood donors and 99.81 % when analyzing unselected samples. Potential cross-reacting factors did not interfere with assay performance. The Elecsys(®) HIV combi PT assay is a sensitive and specific assay that has been granted the CE mark according to Directive 2009/886/EC.


Assuntos
Técnicas de Laboratório Clínico/métodos , Testes Diagnósticos de Rotina/métodos , Anticorpos Anti-HIV/sangue , Proteína do Núcleo p24 do HIV/sangue , Infecções por HIV/diagnóstico , HIV-1/isolamento & purificação , HIV-2/isolamento & purificação , HIV-1/imunologia , HIV-2/imunologia , Humanos , Imunoensaio/métodos , Sensibilidade e Especificidade
7.
Eur J Clin Microbiol Infect Dis ; 31(1): 77-81, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21556676

RESUMO

In the last several years, West Nile virus (WNV) was proven to be present especially in the neighboring countries of Austria, such as Italy, Hungary, and the Czech Republic, as well as in eastern parts of Austria, where it was detected in migratory and domestic birds. In summer 2010, infections with WNV were reported from Romania and northern Greece with about 150 diseased and increasingly fatal cases. We tested the sera of 1,607 blood donors from North Tyrol (Austria) and South Tyrol (Italy) for antibodies against WNV by using IgG enzyme-linked immunosorbent assay (ELISA). Initial results of the ELISA tests showed seroprevalence rates of 46.2% in North Tyrol and 0.5% in South Tyrol, which turned out to be false-positive cross-reactions with antibodies against tick-borne encephalitis virus (TBEV) by adjacent neutralization assays. These results indicate that seropositivity against WNV requires confirmation by neutralization assays, as cross-reactivity with TBEV is frequent and because, currently, WNV is not endemic in the study area.


Assuntos
Anticorpos Antivirais/sangue , Doadores de Sangue , Febre do Nilo Ocidental/epidemiologia , Vírus do Nilo Ocidental/imunologia , Adulto , Pré-Escolar , Vírus da Encefalite Transmitidos por Carrapatos/imunologia , Ensaio de Imunoadsorção Enzimática , Europa (Continente) , Reações Falso-Positivas , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Testes de Neutralização , Febre do Nilo Ocidental/diagnóstico , Febre do Nilo Ocidental/virologia
8.
Tissue Antigens ; 78(5): 397, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21729008

RESUMO

The novel allele HLA-A*68:66 differs from HLA-A*68:01: 01:01 by a synonymous single nucleotide exchange at position 102 (C→T) and three non-synonymous exchanges at position 257 (G→A), position 259 (A→G) and position 261 (C→G) in exon 2.


Assuntos
Antígenos HLA-A/genética , Alelos , Sequência de Bases , Éxons , Humanos , Dados de Sequência Molecular , Alinhamento de Sequência , Análise de Sequência de DNA
9.
Inflamm Res ; 60(2): 127-35, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20740299

RESUMO

INTRODUCTION: Inflammation is crucially involved in a variety of diseases like autoimmune syndromes, cardiovascular and neurodegenerative disorders, cancer, sepsis and allograft rejection. METHODS: Freshly isolated human peripheral blood mononuclear cells (PBMCs) are used as a screening assay for anti-inflammatory properties of compounds. Determinations of neopterin production by ELISA and of tryptophan degradation by HPLC are used as read-outs. Results are compared with further markers of immune response and oxidative stress. RESULTS: Phytohaemagglutinin induced significant tryptophan degradation and neopterin formation in PBMC, which correlated with IFN-γ, TNF-α, soluble cytokine receptors and isoprostane-8. Addition of vitamin C and E suppressed the responses dose-dependently. DISCUSSION: The determination of tryptophan degradation and neopterin production in PBMC reflects various pro- and anti-inflammatory cascades that are of relevance also in patients. It constitutes a robust and reliable approach to screen anti-inflammatory or immunosuppressive drugs and may improve throughput, speed and cost-effectiveness in drug discovery.


Assuntos
Anti-Inflamatórios/farmacologia , Inflamação/imunologia , Leucócitos Mononucleares/efeitos dos fármacos , Anti-Inflamatórios/uso terapêutico , Humanos , Inflamação/tratamento farmacológico , Interferon gama/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Isoprostanos/metabolismo , Leucócitos Mononucleares/imunologia , Mitógenos/farmacologia , Neopterina/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Triptofano/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
10.
Tissue Antigens ; 75(3): 235-41, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20070602

RESUMO

The T-cell immunoglobulin mucin (TIM) gene family encodes receptors on T-cells that regulate Th1- and Th2-cell-mediated immunity. Recently published data implied differential expression of human TIM molecules by mononuclear cells in cerebrospinal fluid of patients with multiple sclerosis (MS) and might therefore be involved in different phases of the pathogenesis of MS. The purpose of this study was to investigate the association of TIM1 gene polymorphism with susceptibility to and clinical progression in MS. In total, 272 patients with MS and 272 sex- and age-matched healthy blood donors from Western Austria were genotyped for 10 single nucleotide polymorphisms (SNPs). Five SNPs were located in the promoter region of TIM1 (rs7702920, rs41297577, rs41297579, rs9313422 and rs34333511). Another five SNPs were selected in exon 4 (rs1553316 and rs12522248) and in the intronic regions 4 and 7 of TIM1 (rs1553318, rs2279804 and rs2277025), respectively. None of these SNPs showed a significant association with MS after correction for multiple comparisons. Haplotype analysis of our data resulted in 11 haplotypes and showed no significant differences between MS patients and controls. Our findings suggest that even fine mapping of TIM1 shows no significant association of this gene with multiple sclerosis.


Assuntos
Imunoglobulinas/genética , Mucina-1/genética , Esclerose Múltipla/genética , Receptores de Superfície Celular/genética , Áustria , Éxons , Genótipo , Haplótipos , Humanos , Imunoglobulinas/metabolismo , Mucina-1/metabolismo , Esclerose Múltipla/metabolismo , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , Receptores de Superfície Celular/metabolismo , Linfócitos T/metabolismo
11.
Vox Sang ; 98(3 Pt 1): e295-363, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20432515

RESUMO

A critical aspect of blood transfusion is the timely provision of high quality blood products. This task remains a significant challenge for many blood services and blood systems reflecting the difficulty of balancing the recruitment of sufficient donors, the optimal utilization of the donor's gift, the increasing safety related restrictions on blood donation, a growing menu of specialized blood products and an ever-growing imperative to increase the efficiency of blood product provision from a cost perspective. As our industry now faces questions about our standard practices including whether or not the age of blood has a negative impact on recipients, it is timely to take a look at our collective inventory management practices. This International Forum represents an effort to get a snap shot of inventory management practices around the world, and to understand the range of different products provided for patients. In addition to sharing current inventory management practices, this Forum is intended to foster an exchange of ideas around where we see our field moving with respect to various issues including specialty products, new technologies, and reducing recipient risk from blood transfusion products.


Assuntos
Bancos de Sangue/organização & administração , Inventários Hospitalares/organização & administração , Adulto , América , Ásia , Bancos de Sangue/estatística & dados numéricos , Preservação de Sangue/métodos , Preservação de Sangue/normas , Preservação de Sangue/estatística & dados numéricos , Transfusão de Sangue/normas , Transfusão de Sangue/estatística & dados numéricos , Criança , Criopreservação , Envelhecimento Eritrocítico , Europa (Continente) , Humanos , Recém-Nascido , Prontuários Médicos , Inquéritos e Questionários , Fatores de Tempo
12.
Clin Nephrol ; 74(6): 465-70, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21084050

RESUMO

BACKGROUND: Hemodialysis patients often present with increased concentrations of tryptophan catabolites perhaps related to an enhanced activity of tryptophan-degrading enzyme indoleamine 2,3-dioxygenase (IDO) that is inducible by pro-inflammatory stimuli. The often chronic inflammation and immune activation status in dialysis patients may accelerate tryptophan degradation, which could influence patients' psychological performance. PATIENTS AND METHODS: In this study, plasma concentrations of kynurenine and tryptophan were determined by HPLC in 75 dialysis patients, aged 65.3 ± 15.0 years. Forty patients were female, 35 male; 21 (28%) had diabetes mellitus Type 1 or 2 and 32 (43%) suffered from sleep disturbances and/or depression. Their dialysis vintage was 4.26 ± 4.72 years. HPLC results were compared to concentrations obtained from 40 healthy blood donors, to immune activation marker neopterin, and to psychological test results based on INTERMED scores. RESULTS: Compared to those in healthy controls, tryptophan concentrations were decreased in patients. Neopterin, kynurenine and the kynurenine to tryptophan ratio (kyn/trp, an index of tryptophan degradation) were increased in patients (all p < 0.01). Kyn/trp correlated with neopterin concentrations (rs = 0.393, p < 0.01). INTERMED scores were 21.0 + 8.4 and slightly higher in females (U = -1.831, p < 0.07); they correlated with tryptophan concentrations (rs = -0.227, p < 0.05) but with no other parameter studied. Data point to a possible relationship between tryptophan metabolic disturbances and psychologic presentation of patients, although only a rather weak relationship was found. CONCLUSION: We conclude that tryptophan degradation is increased in dialysis patients. The association with increased neopterin concentrations indicates activated IDO.


Assuntos
Diálise Renal , Triptofano/sangue , Uremia/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Áustria , Biomarcadores/sangue , Estudos de Casos e Controles , Cromatografia Líquida de Alta Pressão , Ativação Enzimática , Feminino , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Cinurenina/sangue , Masculino , Pessoa de Meia-Idade , Neopterina/sangue , Qualidade de Vida , Resultado do Tratamento , Uremia/sangue , Uremia/psicologia , Adulto Jovem
13.
Int Arch Allergy Immunol ; 147(1): 35-40, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18446051

RESUMO

BACKGROUND/AIMS: The immunologic background of allergic asthma and rhinitis includes a preponderance of Th2-type immunity. In parallel, Th1-type immune response is suppressed by Th2-type cytokines. As a consequence, biochemical pathways triggered by Th1-type cytokine interferon-gamma, such as tryptophan degradation by indoleamine 2,3-dioxygenase and neopterin production, might be altered. We examined whether they are related to the outcome of hyposensitization therapy in atopic patients. METHODS: In serum specimens of 44 atopic patients (18 women, 26 men) before any specific immunotherapy, tryptophan and kynurenine concentrations were measured by HPLC, and the kynurenine to tryptophan ratio (kyn/trp) was calculated. Neopterin concentrations were measured by ELISA. Results were compared with concentrations in 38 serum specimens from healthy blood donors and with the outcome of specific subcutaneous immunotherapy in atopics: on clinical grounds, 27 patients were classified as responders, and 17 patients as non-responders. RESULTS: Serum tryptophan concentrations were higher in atopics (84.3 +/- 24.4 microM) than in blood donors (57.9 +/- 7.46 microM; p < 0.001), kynurenine and kyn/trp were not different between the 2 groups. All of the neopterin concentrations measured in patients were <8.7 nM, the upper limit of the normal. Non-responders to subcutaneous immunotherapy had significantly higher tryptophan concentrations (95.7 +/- 27.0 microM) than responders (77.1 +/- 19.9 microM; p = 0.01). No other marker concentrations differed between the groups. CONCLUSIONS: The measurement of serum tryptophan may present an option to predict the outcome of pollen extract therapy. Higher tryptophan levels may result from lower indoleamine 2,3-dioxygenase activity in atopics. However, this possible relationship needs to be confirmed in further studies.


Assuntos
Biomarcadores/sangue , Dessensibilização Imunológica , Rinite Alérgica Sazonal/sangue , Triptofano/sangue , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Cinurenina/sangue , Masculino , Neopterina/sangue , Pólen/imunologia , Rinite Alérgica Sazonal/tratamento farmacológico , Rinite Alérgica Sazonal/imunologia , Triptofano/metabolismo
15.
Oxid Med Cell Longev ; 2018: 2980295, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29576845

RESUMO

Several phytochemicals were shown to interfere with redox biology in the human system. Moreover, redox biochemistry is crucially involved in the orchestration of immunological cascades. When screening for immunomodulatory compounds, the two interferon gamma- (IFN-γ-) dependent immunometabolic pathways of tryptophan breakdown via indoleamine 2,3-dioxygenase-1 (IDO-1) and neopterin formation by GTP-cyclohydrolase 1 (GTP-CH-I) represent prominent targets, as IFN-γ-related signaling is strongly sensitive to oxidative triggers. Herein, the analysis of these pathway activities in human peripheral mononuclear cells was successfully applied in a bioactivity-guided fractionation strategy to screen for anti-inflammatory substances contained in the root of Horminum (H.) pyrenaicum L. (syn. Dragon's mouth), the only representative of the monophyletic genus Horminum. Four abietane diterpene quinone derivatives (horminone, 7-O-acetylhorminone, inuroyleanol and its 15,16-dehydro-derivative, a novel natural product), two nor-abietane diterpene quinones (agastaquinone and 3-deoxyagastaquinone) and two abeo 18 (4 → 3) abietane diterpene quinones (agastol and its 15,16-dehydro-derivative) could be identified. These compounds were able to dose-dependently suppress the above mentioned pathways with different potency. Beside the description of new active compounds, this study demonstrates the feasibility of integrating IDO-1 and GTP-CH-I activity in the search for novel anti-inflammatory compounds, which can then be directed towards a more detailed mode of action analysis.


Assuntos
Diterpenos/farmacologia , Lamiaceae/química , Leucócitos Mononucleares/efeitos dos fármacos , Quinonas/farmacologia , Células Cultivadas , Diterpenos/química , Humanos , Fatores Imunológicos/farmacologia , Cinurenina/sangue , Leucócitos Mononucleares/imunologia , Neopterina/sangue , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Quinonas/química , Triptofano/sangue
18.
Int Immunopharmacol ; 6(3): 390-5, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16428074

RESUMO

Moderate consumption of alcoholic beverages is suggested to reduce cardiovascular risk. Within this context, most attention is drawn to antioxidant ingredients of wine, but also beer was found to be beneficial. Potential effects of three different types of beer including alcohol-free beer were investigated using freshly isolated human peripheral blood mononuclear cells stimulated with the mitogen phytohaemagglutinin in vitro. Neopterin production and tryptophan degradation were monitored in culture supernatants to determine effects of test substances on immunobiochemical pathways induced by interferon-gamma. In a subgroup of experiments also production of interferon-gamma was measured. Compared to unstimulated cells, phytohaemagglutinin increased production of neopterin and also triggered the degradation of tryptophan (all p < 0.01). All types of beer (2-4% dilution) were found to counteract these stimulation-induced effects and significant reduction of neopterin formation and tryptophan degradation was observed (p < 0.01). Data demonstrate that beer reduces production of neopterin and degradation of tryptophan, both these biochemical pathways are induced during cell-mediated immune response. Data suggest that the immunosuppressive capacity of beer may relate to its anti-inflammatory nature.


Assuntos
Cerveja , Regulação para Baixo/imunologia , Imunossupressores/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Células Cultivadas , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Humanos , Imunidade Celular/efeitos dos fármacos , Interferon gama/metabolismo , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Neopterina/antagonistas & inibidores , Neopterina/biossíntese , Fito-Hemaglutininas/farmacologia , Triptofano/antagonistas & inibidores , Triptofano/metabolismo
19.
Curr Pharm Biotechnol ; 5(1): 107-18, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14965213

RESUMO

Moderate hyperhomocysteinemia is associated with an increased risk of atherosclerosis, thrombosis and neurodegenerative diseases. Homocysteine accumulation in the blood can be due to many underlying causes, which may interact with each other, e.g. genetic disposition and B-vitamin status. The role of the sulfur-containing amino acid homocysteine in the pathogenesis of diseases remains unclear, even if many studies suggest a causal relationship between homocysteine-mediated processes like oxidative stress, NO-inactivation and endothelial deficiency and atherogenesis. Proposed mechanisms of action of homocysteine are discussed, and the question is addressed, whether effects that are attributed to homocysteine, are not rather the consequence of folate and vitamin B12-deficiency. Deficiency of these B-vitamins in parallel with moderate hyperhomocysteinemia is often found in patients with enhanced activation of the cellular immune system, like Alzheimer's disease, rheumatoid arthritis and also vascular diseases. In patients with these diseases an association between homocysteine metabolism, oxidative stress and immune activation exists. On the one hand proliferation of immunocompetent cells having an enhanced demand for B-vitamins leads to the accumulation of homocysteine. On the other hand macrophages stimulated by TH1-type cytokine interferon-gamma form reactive oxygen species (ROS), which oxidize antioxidants, lipoproteins and oxidation-sensitive B-vitamins. Thereby Th1-type immune response could contribute importantly to the development of hyperhomocysteinemia, and may also be a major determinant of disease progression.


Assuntos
Hiper-Homocisteinemia/imunologia , Hiper-Homocisteinemia/metabolismo , Animais , Humanos , Células Th1/imunologia , Células Th1/metabolismo , Deficiência de Vitamina B 12/imunologia , Deficiência de Vitamina B 12/metabolismo
20.
Bone Marrow Transplant ; 31(6): 497-506, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12665847

RESUMO

The role of human platelet alloantigens (HPA) in clinical bone marrow allotransplantation was investigated. The leading hypothesis was that HPA alloepitopes act as minor histocompatibility antigens and aggravate graft-versus-host disease (GVHD). To exclude the effect of MHC disparity, only HLA identical donor-recipient pairs were entered into the study. The influence of HPA compatibility on overall survival, occurrence of relapses and haematopoietic recovery was also investigated. A total of 223 patients who received a graft from an HLA-identical sibling, genotyped for HPA -1, -2, -3, -4 and -5, were observed over a post-transplant period of 24 months following the protocol recommended by EBMT. The data from patients having received grafts from HPA compatible donors were compared to data from patients having received grafts that were mismatched in HPA allotypes in the GVH direction. Analysis of the incidence of acute and chronic (GVHD), overall survival, relapse incidence, haematopoietic recovery and some other clinical parameters did not reveal any significant difference between the HPA-matched and -mismatched groups of patients, regardless of their age. Our results give no evidence that HPA-1, -2, -3 and -5 alloantigens should be considered minor transplantation antigens in clinical bone marrow transplantation.


Assuntos
Antígenos de Plaquetas Humanas/imunologia , Plaquetas/imunologia , Transplante de Medula Óssea/imunologia , Antígenos de Histocompatibilidade Menor/imunologia , Adulto , Antígenos de Plaquetas Humanas/genética , Feminino , Sobrevivência de Enxerto/imunologia , Doença Enxerto-Hospedeiro/genética , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/mortalidade , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Antígenos de Histocompatibilidade Menor/genética , Polimorfismo Genético , Recidiva , Taxa de Sobrevida
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