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1.
Leuk Res ; 129: 107058, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37080000

RESUMO

BACKGROUND: Retrospective studies in hematological unit have suggested that single red blood cell (1-RBC) unit transfusion policy may reduce the number of RBC used without negative clinical impact. METHOD: Acute leukemia patients requiring intensive chemotherapy or patients receiving autologous or allogeneic transplantation were randomly assigned to receive either single RBC (1-RBC arm) or double RBC (2-RBC arm) per transfusion with a hemoglobin trigger of 8 g/dL. The primary composite endpoint was the percentage of patients experiencing serious complications, such as a non-hematological adverse event grade ≥ 3 or intensive care admission or death. FINDINGS: A total of 981 and 592 RBC transfusions were required in the 1-RBC arm (n = 125) and the 2-RBC arm (n = 120), respectively. The mean pre-transfusion hemoglobin levels were 7.49 ± 0.83 g/dL in the 1-RBC arm and 7.46 ± 0.67 g/dL in the 2-RBC arm (p = 0.275). The predefined non-inferiority criteria was achieved with 28/125 patients reaching the primary endpoint in the 1-RBC arm (22.4 %) and 28/120 patients in the 2-RBC arm (23.3 %) (Risk difference 0.009; 95 %, Confidence interval [-0.0791 to 0.0978], p = 0.021). The median (IQR) of RBC units transfused per patient was 7 (4-12) in the 1-RBC arm and 8 (4-12) in 2-RBC arm. Hemoglobin levels at discharge were also comparable in both arms. INTERPRETATION: The results of this trial indicate that a single RBC transfusion policy is not inferior to a double RBC transfusion policy for patients receiving a bone marrow transplant or intensive chemotherapy in a hematological intensive care unit. However, the single RBC transfusion policy did not reduce the number of RBC units transfused per stay. FUNDING: This trial was funded by a grant from the French Ministry of Health.


Assuntos
Doenças Hematológicas , Leucemia Mieloide Aguda , Humanos , Estudos Retrospectivos , Transfusão de Eritrócitos/efeitos adversos , Hemoglobinas , Leucemia Mieloide Aguda/etiologia , Doença Aguda
3.
Curr Res Transl Med ; 67(4): 145-148, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30871955

RESUMO

INTRODUCTION: The most used preemptive therapy for Epstein Barr virus reactivation post allogeneic hematopoietic stem cell (HSCT) transplant is Rituximab, 375 mg/m2, once weekly until EBV viremia negativity. There is no data suggesting such a high dose. OBJECTIVE: We hypothesized that a lower dose of Rituximab would be as efficient with less toxicity. PATIENTS: In a retrospective, monocentric study, we analyzed 16 consecutive patients treated preemptively with low dose Rituximab for EBV reactivation post HSCT. Patients were treated with low Rituximab dose of 100 mg/m² weekly. Success was defined by a decrease of EBV viremia of 1 log10 and below 1000 UI/ml, and the absence of post-transplant lymphoproliferative disorder (PTLD). RESULTS: Success rate was 93.4% (15/16). One (1/16, 6%) PTLD was diagnosed after preemptive therapy, despite a negative viremia. CONCLUSION: A low dose of Rituximab of 100 mg/m² per injection for pre-emptive therapy of EBV reactivation post HSCT is safe and effective for preventing PTLD. Prospective, randomized, multicentric trials with larger number of patient are needed to determine the best rituximab dose.


Assuntos
Quimioprevenção , Infecções por Vírus Epstein-Barr/prevenção & controle , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas , Herpesvirus Humano 4/efeitos dos fármacos , Rituximab/administração & dosagem , Ativação Viral/efeitos dos fármacos , Adolescente , Adulto , Idoso , Quimioprevenção/métodos , Relação Dose-Resposta a Droga , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/epidemiologia , Infecções por Vírus Epstein-Barr/imunologia , Feminino , Doença Enxerto-Hospedeiro/epidemiologia , Doença Enxerto-Hospedeiro/imunologia , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/epidemiologia , Neoplasias Hematológicas/imunologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/estatística & dados numéricos , Herpesvirus Humano 4/fisiologia , Humanos , Hospedeiro Imunocomprometido , Terapia de Imunossupressão/efeitos adversos , Masculino , Pessoa de Meia-Idade , Profilaxia Pós-Exposição/métodos , Estudos Retrospectivos , Condicionamento Pré-Transplante/efeitos adversos , Transplante Homólogo , Resultado do Tratamento , Viremia/imunologia , Viremia/prevenção & controle , Adulto Jovem
4.
Rev Neurol ; 65(10): 457-468, 2017 Nov 16.
Artigo em Espanhol | MEDLINE | ID: mdl-29130469

RESUMO

INTRODUCTION: A number of neurodegenerative disorders have been linked directly to the accumulation of amyloid fibres. These fibres are made up of proteins or peptides with altered structures and which join together in vivo in association with heparan sulphate-type polysaccharides. AIMS: To examine the most recent concepts in the biology of heparan sulphates and their role in the aggregation of the peptide Abeta, of tau protein, of alpha-synuclein and of prions. The study also seeks to analyse their implications in neurodegenerative disorders such as Alzheimer's and Parkinson's disease and prion diseases. DEVELOPMENT: In vitro, heparan sulphates have played an important role in the process of oligomerisation and fibrillation of amyloidogenic proteins or peptides, in the stabilisation of these bodies and their resistance to proteolysis, thereby participating in the formation of a wide range of amyloid fibres. Heparan sulphates have also been related to the internalisation of pro-amyloid fibres during the process of intercellular propagation (spreading), which is considered to be crucial in the development of proteinopathies, the best example of which is Alzheimer's disease. CONCLUSION: This study suggests that the fine structures of heparan sulphates, their localisation in cells and tissues, together with their local concentration, may regulate the amyloidosis processes. The advances made in the understanding of this area of glyconeurobiology will make it possible to improve the understanding of the cell and molecular mechanisms underlying the neurodegenerative process.


TITLE: Heparan sulfatos, amiloidosis y neurodegeneracion.Introduccion. Numerosos trastornos neurodegenerativos se han asociado directamente a la acumulacion de fibras amiloides. Estas fibras estan formadas por proteinas o peptidos con conformaciones alteradas y que se agregan in vivo en asociacion con polisacaridos de tipo heparan sulfatos. Objetivos. Examinar los conceptos mas recientes sobre la biologia de los heparan sulfatos y su papel en la agregacion del peptido Abeta, de la proteina tau, de la alfa-sinucleina y de los priones, y analizar sus implicaciones en trastornos neurodegenerativos como las enfermedades de Alzheimer y de Parkinson y las enfermedades prionicas. Desarrollo. In vitro, los heparan sulfatos han desempeñado un papel importante en el proceso de oligomerizacion y fibrilacion de proteinas o peptidos amiloidogenos, en la estabilizacion de estos cuerpos y su resistencia a la proteolisis, participando asi en la formacion de una gran variedad de fibras amiloides. Los heparan sulfatos se han relacionado tambien con el proceso de internalizacion de fibras proamiloides durante el proceso de propagacion intercelular (spreading) considerado como central en la evolucion de las proteinopatias, cuyo mejor ejemplo es la enfermedad de Alzheimer. Conclusion. Este trabajo sugiere que las estructuras finas de los heparan sulfatos, sus localizaciones celulares y tisulares, asi como sus concentraciones locales, pueden regular los procesos de amiloidosis. Avances en la comprension de esta area de la gliconeurobiologia permitiran mejorar la comprension de los mecanismos celulares y moleculares del proceso neurodegenerativo.


Assuntos
Amiloidose/etiologia , Heparitina Sulfato/fisiologia , Doenças Neurodegenerativas/etiologia , Doença de Alzheimer/etiologia , Animais , Modelos Animais de Doenças , Humanos , Doença de Parkinson/etiologia , Doenças Priônicas/etiologia
5.
Ann Oncol ; 28(9): 2191-2198, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28911060

RESUMO

BACKGROUND: Fludarabine/busulfan-based conditioning regimens are widely used to perform allogeneic stem-cell transplantation (allo-SCT) in high-risk non-Hodgkin lymphoma (NHL) patients. The impact of the dose intensity of busulfan on outcomes has not been reported yet. PATIENTS AND METHODS: This was a retrospective with the aim to compare the outcomes of NHL patients who received before allo-SCT a fludarabine/busulfan conditioning regimen, either of reduced intensity (FB2, 2 days of busulfan at 4 mg/kg/day oral or 3.2 mg/kg/day i.v.) (n = 277) or at a myeloablative reduced-toxicity dose (FB3/FB4, 3 or 4 days of busulfan at 4 mg/kg/day oral or 3.2 mg/kg/day i.v.) (n = 101). RESULTS: In univariate analysis, the 2-year overall survival (FB2 66.5% versus 60.3%, P = 0.33), lymphoma-free survival (FB2 57.9% versus 49.8%, P = 0.26), and non-relapse mortality (FB2 19% versus 21.1%, P = 0.91) were similar between both groups. Cumulative incidence of grade III-IV acute graft versus host disease (GVHD) (FB2 11.2% versus 18%, P = 0.08), extensive chronic GVHD (FB2: 17.3% versus 10.7%, P = 0.18) and 2-year GVHD free-relapse free survival (FB2: 44.4% versus 42.8%, P = 0.38) were also comparable. In multivariate analysis there was a trend for a worse outcome using FB3/FB4 regimens (overall survival: HR 1.47, 95% CI: 0.96-2.24, P = 0.08; lymphoma-free survival: HR: 1.43, 95% CI: 0.99-2.06, P = 0.05; relapse incidence: HR 1.54; 95% CI: 0.96-2.48, P = 0.07). These results were confirmed using a propensity score-matching strategy. CONCLUSION: We conclude that reduced toxicity myeloablative conditioning with fludarabine/busulfan does not improve the outcomes compared with reduced-intensity conditioning in adults receiving allo-SCT for NHL.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bussulfano/administração & dosagem , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Linfoma não Hodgkin/terapia , Condicionamento Pré-Transplante , Vidarabina/análogos & derivados , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Feminino , Doença Enxerto-Hospedeiro , Humanos , Linfoma não Hodgkin/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Vidarabina/administração & dosagem , Adulto Jovem
6.
Heredity (Edinb) ; 119(2): 76-87, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28402327

RESUMO

The genetic variance-covariance matrix (G-matrix) summarizes the genetic architecture of multiple traits. It has a central role in the understanding of phenotypic divergence and the quantification of the evolutionary potential of populations. Laboratory experiments have shown that G-matrices can vary rapidly under divergent selective pressures. However, because of the demanding nature of G-matrix estimation and comparison in wild populations, the extent of its spatial variability remains largely unknown. In this study, we investigate spatial variation in G-matrices for morphological and life-history traits using long-term data sets from one continental and three island populations of blue tit (Cyanistes caeruleus) that have experienced contrasting population history and selective environment. We found no evidence for differences in G-matrices among populations. Interestingly, the phenotypic variance-covariance matrices (P) were divergent across populations, suggesting that using P as a substitute for G may be inadequate. These analyses also provide the first evidence in wild populations for additive genetic variation in the incubation period (that is, the period between last egg laid and hatching) in all four populations. Altogether, our results suggest that G-matrices may be stable across populations inhabiting contrasted environments, therefore challenging the results of previous simulation studies and laboratory experiments.


Assuntos
Variação Genética , Genética Populacional , Modelos Genéticos , Passeriformes/genética , Animais , Feminino , Ilhas , Características de História de Vida , Masculino , Linhagem , Fenótipo
7.
Ann Dermatol Venereol ; 144(4): 268-274, 2017 Apr.
Artigo em Francês | MEDLINE | ID: mdl-28242092

RESUMO

BACKGROUND: Lymphoblastic lymphoma (LBL) is a rare form of non-Hodgkin's lymphoma (NHL). Cutaneous LBL is seen in less than 20% of patients. PATIENTS AND METHODS: Herein, we report the case of a 66-year-old male patient without any previous disease history of note and who was presenting a gradually spreading tumoral lesion of the scalp, several purplish macules and nodules on the trunk, and a single spinal adenopathy. A thoracic-abdominal-pelvic CT scan performed for acute renal failure, revealed extensive infiltration of retroperitoneal tissue. Skin biopsies and staging tests indicated LBL-T with associated cutaneous, bone and lymph node retroperitoneal lesions with no mediastinal mass. After two months of treatment with CHOP (four courses), the cutaneous lesions and abdominal tumoral mass had regressed and renal function had returned to normal. DISCUSSION: There have been 13 reported cases of LBL with cutaneous involvement; most of these patients were young (under 30 years) and presented multiple cutaneous lesions (nodules or tumors) associated with numerous peripheral adenopathies, invasion of the bone marrow, and in many cases, a mediastinal mass. The clinical presentation of LBL-T in our case is novel on account of the cutaneous sites, associated with abdominal tumoral syndrome, without mediastinal infiltration, and with a single peripheral adenopathy, in an elderly subject.


Assuntos
Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Pele/patologia , Injúria Renal Aguda/etiologia , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Osso e Ossos/patologia , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Humanos , Imunofenotipagem , Infiltração Leucêmica/patologia , Linfonodos/patologia , Masculino , Mercaptopurina/administração & dosagem , Metotrexato/administração & dosagem , Especificidade de Órgãos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Prednisona/administração & dosagem , Espaço Retroperitoneal , Vincristina/administração & dosagem
8.
Int J Hematol ; 104(1): 85-91, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27040278

RESUMO

Splenectomy remains the preferred treatment for chronic immune thrombocytopenia (ITP) after corticosteroid failure, despite the risks of despite surgical complications and infection. The aim of this study was to assess the efficacy of and tolerance to rituximab through a retrospective analysis of 35 refractory/relapsing ITP patients treated from 2004 to 2013. The median age of subjects was 46 years (14-80). Rituximab was given at a weekly dose of 375 mg/m(2) for 4 weeks. Median time from diagnosis to first infusion was 17 months (1-362) and follow-up was 47 months (2-133). The overall response rates at 1 and 2 years after the first infusion were 47 and 38 %, with complete response rates of 24 and 25 %, respectively. Median duration of response was 38 months (1-123), with 37 % of patients maintaining a durable response (>1 year). Twenty-nine percent of patients had undergone splenectomy. A durable response after rituximab was more frequently observed in patients undergoing second-line therapy than those in third or later (83 versus 35 %, P = 0.01). Forty-four percent of patients experienced mild hypogammaglobulinaemia after rituximab, and no clinical infection occurred. To conclude, rituximab should be considered as an alternative treatment to splenectomy. Its efficacy and safety profile should lead us to choose this medical option therapy before surgery for ITP patients.


Assuntos
Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Rituximab/uso terapêutico , Terapia de Salvação/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Disgamaglobulinemia/induzido quimicamente , Humanos , Pessoa de Meia-Idade , Púrpura Trombocitopênica Idiopática/cirurgia , Estudos Retrospectivos , Rituximab/efeitos adversos , Terapia de Salvação/normas , Esplenectomia , Resultado do Tratamento , Adulto Jovem
10.
Case Rep Med ; 2015: 657049, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26236345

RESUMO

Cervical bilateral lymphadenopathy is a frequent event during chronic lymphocytic leukemia (CLL) natural history. However, lymph node biopsy is generally not required as long as transformation into an aggressive lymphoma (Richter syndrome) is not suspected. We present here a rare case of CLL patient who developed progressive bilateral cervical lymph node and bilateral tonsillar hypertrophy. CLL front-line therapy was ineffective leading to adenectomy and diagnosis of concomitant extramedullary plasmacytoma. Radiotherapy did not result in the disappearance of lymphadenopathy. Adenectomy should be performed in CLL cases to avoid misdiagnosis.

11.
Rev Mal Respir ; 32(1): 84-6, 2015 Jan.
Artigo em Francês | MEDLINE | ID: mdl-25618211
12.
Leuk Res ; 38(9): 1020-4, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25073661

RESUMO

To avoid repeated apheresis, the objective of this study was to analyse the predictive factors for a single successful cytapheresis during the first mobilisation. The pre-collection characteristics of 170 lymphoma and 95 myeloma patients were analysed. Among 60 lymphoma patients who had less than 30 CD34 cells/mm(3) the day before the first apheresis, an increase in the CD34 cell count between Day -1 and Day 1 was predictive of first stem cell mobilisation success, with a sensitivity of 100% if the Day 1 was higher than 30/mm(3) (10/60 patients). Success rate of obtaining an appropriate number of stem cells in one apheresis was 120 among 170 patients.


Assuntos
Citaferese/métodos , Mobilização de Células-Tronco Hematopoéticas/métodos , Linfoma/diagnóstico , Linfoma/terapia , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/terapia , Adulto , Idoso , Antígenos CD34/sangue , Estudos de Coortes , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Linfoma/sangue , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/sangue , Valor Preditivo dos Testes , Prognóstico , Condicionamento Pré-Transplante/métodos , Transplante Autólogo , Resultado do Tratamento , Adulto Jovem
13.
Leuk Res ; 38(5): 569-74, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24655805

RESUMO

In reduced-toxicity conditioning hematopoietic stem cell transplantation, several studies failed to demonstrate the superiority of one conditioning over another. This study described 51 patients (median age of 58 years) allografted with the new FB3-ATG2 conditioning regimen for myeloid (66%) or lymphoid disease (33%). Comorbidity index ≥3 was noted in 23.5% of patients. Toxicities were close to those observed with RIC. One-year cumulative incidence of acute and chronic GVHD was 18.9% and 39.2%. The 2-year-NRM, DFS and OS were 25%, 57.5% and 66%. The FB3-ATG2 regimen is safe and efficient in both lymphoid and myeloid disorders. However, prospective comparative studies are needed.


Assuntos
Soro Antilinfocitário/administração & dosagem , Bussulfano/administração & dosagem , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Condicionamento Pré-Transplante/métodos , Vidarabina/análogos & derivados , Adulto , Idoso , Estudos de Viabilidade , Feminino , Doença Enxerto-Hospedeiro/epidemiologia , Transplante de Células-Tronco Hematopoéticas/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Transplante Homólogo , Vidarabina/administração & dosagem
15.
Leuk Res ; 37(11): 1404-11, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23932356

RESUMO

Hematogones were initially described as mysterious cells in bone marrow smears more than 70 years ago. These cells are normal bone marrow B-lymphocyte precursors with properties that overlap those of lymphoblasts. Their morphological and immunological features are described here with an update on the knowledge of hematogones in hematological and non-hematological disorders.


Assuntos
Neoplasias Hematológicas/diagnóstico , Células Precursoras de Linfócitos B/patologia , Animais , Humanos
17.
Bone Marrow Transplant ; 48(5): 684-90, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23165497

RESUMO

To assess the role of hematopoietic SCT (HSCT) in adult ALL patients with central nervous system involvement at diagnosis, we retrospectively analyzed 90 patients who underwent autologous HSCT (auto-HSCT group; n=27) or allogeneic HSCT (allo-HSCT group; n=63) and reported to the Société Française de Greffe de Moelle et de Thérapie Cellulaire registry between 1994 and 2008. At the time of transplantation, 67 patients (74%) were in first CR, 15 (17%) in CR2 and 8 (9%) with progressive disease. The 5-year probabilities of overall survival (OS) and disease-free survival (DFS) were 52% and 46% for the allo-HSCT and 37% and 33% for the auto-HSCT groups, respectively (P=NS). The TRM at 5 years was 29.8% for the allo-HSCT group and 3.7% for the auto-HSCT group. Using univariate analysis, a time for transplantation of <12 months, the remission status at transplantation, the use of high-dose TBI and the number of the transplant were all determined to be prognostic factors for improved DFS and OS probabilities. Using multivariate analysis, we demonstrated that both the use of high-dose TBI and the remission status had a favorable impact on OS. Although the DFS and OS were better in the allo-HSCT group, the differences were not statistically significant.


Assuntos
Neoplasias do Sistema Nervoso Central/cirurgia , Transplante de Células-Tronco Hematopoéticas/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/cirurgia , Adolescente , Adulto , Neoplasias do Sistema Nervoso Central/diagnóstico , Intervalo Livre de Doença , Humanos , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Estudos Retrospectivos , Transplante Autólogo , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
18.
Arch Pediatr ; 12(11): 1570-6, 2005 Nov.
Artigo em Francês | MEDLINE | ID: mdl-16216481

RESUMO

UNLABELLED: The aims of this work were to assess timing of complementary feeding in infants and to precise the underlying factors that may cause inappropriate complementary feeding. PATIENTS AND METHODS: A cohort of 167 newborns, born in the same maternity ward during a 6 week-period, was prospectively analyzed. Only healthy neonates were included in the study. A phone questionnaire was filled at 4 and 6 months of age to evaluate modality of complementary feeding. Multivariate analysis (segmentation tree, analyse by multiple correspondence) was used to study factors associated with inappropriate diversification. RESULTS: Out of the 167 neonates included in the study, 132 mothers could be contacted at 4 months and 116 at 6 months of age. Sixty-seven per cent of mothers started breast feeding at birth. Among these, 33% still breastfed -at least partially- at 4 months and 17% at 6 months. Fifty-two percent of mothers started complementary feeding before 4 months, and 24% of infants received gluten at 4 months of age. Multi-gravida mothers, mothers aged more than 35 years old and mothers who gave infant or follow-up formulae before 4 months, started complementary feeding significantly earlier (P<0.05). Infants who were formula fed received more frequently complementary feeding before the age of 4 months than breast fed infants (57% vs 33%, P<0.05). CONCLUSION: Our study showed that half of infants were introduced solid food too early and allowed to identify a population at risk that could benefit from nutritional intervention programs.


Assuntos
Aleitamento Materno , Alimentos Infantis , Fenômenos Fisiológicos da Nutrição do Lactente , Adulto , Desenvolvimento Infantil , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos , Fatores de Risco
19.
Diabetologia ; 48(3): 529-38, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15729582

RESUMO

AIMS/HYPOTHESIS: Elevated oxidative stress, hyperglycaemia, and dyslipidaemia involving low levels of HDL particles are key proatherogenic factors in type 2 diabetes mellitus. We examined the relationship of oxidative stress, and the degree of glycaemia and triglyceridaemia, to antioxidative function of HDL particle subspecies in type 2 diabetes. SUBJECTS AND METHODS: Five HDL subfractions (2b, 2a, 3a, 3b, 3c) were isolated by density gradient ultracentrifugation from well-controlled type 2 diabetic subjects (n=20) and normolipidaemic, non-diabetic controls (n=10). Specific antioxidative activity (capacity to protect LDL from oxidation on a unit particle mass or on a particle number basis), chemical composition and enzymatic activities were measured in each subfraction. Systemic oxidative stress was assessed as plasma levels of 8-isoprostanes. RESULTS: Specific antioxidative activity of small dense HDL3b and 3c particles in diabetic patients was significantly diminished (up to -47%, on a particle mass or particle number basis) as compared with controls. Plasma 8-isoprostanes were markedly elevated (2.9-fold) in diabetic patients, were negatively correlated with both specific antioxidative activity of HDL3 subfractions and plasma HDL cholesterol (HDL-C) levels, and were positively correlated with glycaemia and triglyceridaemia. Paraoxonase 1 activity was consistently lower in diabetic HDL subfractions and was positively correlated with HDL3 antioxidative activity. The altered chemical composition of diabetic HDL3 subfractions (core cholesteryl ester depletion, triglyceride enrichment) was equally correlated with diminished antioxidative activity. CONCLUSIONS/INTERPRETATION: Antioxidative activity of small dense HDL is deficient in type 2 diabetes, is intimately linked to oxidative stress, glycaemia and hypertriglyceridaemia and primarily reflects abnormal intrinsic physicochemical properties of HDL particles.


Assuntos
Antioxidantes/metabolismo , Diabetes Mellitus Tipo 2/sangue , Hiperglicemia/sangue , Lipoproteínas HDL/sangue , Estresse Oxidativo/fisiologia , Arildialquilfosfatase/sangue , Centrifugação com Gradiente de Concentração , Colesterol/sangue , Hemoglobinas Glicadas/análise , Humanos , Lipoproteínas HDL3 , Lipoproteínas LDL/sangue , Lipoproteínas LDL/isolamento & purificação , Fosfolipídeos/sangue , Triglicerídeos/sangue
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