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1.
Ann Dermatol Venereol ; 150(3): 189-194, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37225615

RESUMO

BACKGROUND: The factors associated with early relapse of infantile haemangioma (IH) after a first course of treatment with oral propranolol for at least six months (initiated after the marketing authorization had been granted) have not previously been investigated. OBJECTIVES: To identify factors associated with the risk of early relapse in children with IH treated with oral propranolol according to the current prescribing guidelines. METHODS: We performed a multicentre, retrospective, case-control study, using the Ouest Data Hub database. All children treated for at least 6 months with oral propranolol for IH between 31 June 2014 and 31 December 2021, and with a follow-up visit at least three months after treatment discontinuation were included. A case was defined as relapse of IH within three months of treatment discontinuation; each case was matched for age at treatment initiation and for centre, with four (relapse-free) controls. The association between relapse and treatment or IH characteristics was expressed as an odds ratio (OR) from univariate and multivariate conditional logistic regressions. RESULTS: A total of 225 children were included. Of these, 36 (16%) relapsed early. In a multivariate analysis, a deep IH component was a risk factor for early relapse [OR = 8.93; 95%CI: 1.0-78.9, p = 0.05]. A propranolol dosage level of less than 3 mg/kg/day protected against early relapse [OR = 0.11; 95%CI: 0.02-0.7, p = 0.02]. Tapering before propranolol discontinuation was not associated with a lower risk of early relapse. CONCLUSION: The risk factors for late and early relapse are probably different. Investigation of the risk factors for early vs. late IH relapse is now warranted.


Assuntos
Hemangioma Capilar , Neoplasias Cutâneas , Criança , Humanos , Lactente , Estudos de Casos e Controles , Estudos Retrospectivos , Propranolol/uso terapêutico , Doença Crônica , Resultado do Tratamento , Administração Oral , Neoplasias Cutâneas/tratamento farmacológico
3.
Cancer Immunol Immunother ; 72(6): 1881-1890, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36690799

RESUMO

INTRODUCTION: Pembrolizumab alone (IO-mono) or in combination with platinum-based chemotherapy (CT-IO) is first-line standard of care for advanced non-small cell lung cancer (NSCLC) patients with PD-L1 ≥ 50%. This retrospective multicentre study assessed real-world use and efficacy of both strategies. METHODS: Patients with advanced NSCLC PD-L1 ≥ 50% from eight hospitals who had received at least one cycle of IO-mono or CT-IO were included. Overall survival (OS) and real-word progression-free-survival were estimated using Kaplan-Meier methodology. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95% CIs, and a Cox model with inverse propensity treatment weighting was carried out. RESULTS: Among the 243 patients included, 141 (58%) received IO-mono and 102 (42%) CT-IO. Younger patients, those with symptomatic disease and brain metastases were more likely to be proposed CT-IO. With a median follow-up of 11.5 months (95% CI 10.4-13.3), median OS was not reached, but no difference was observed between groups (p = 0.51). Early deaths at 12 weeks were 11% (95% CI 4.6-16.9) and 15.2% (95% CI 9.0-20.9) in CT-IO and IO groups (p = 0.32). After adjustment for age, gender, performance status, histology, brain metastases, liver metastases and tobacco status, no statistically significant difference was found for OS between groups, neither in the multivariate adjusted model [HR 1.07 (95% CI 0.61-1.86), p = 0.8] nor in propensity adjusted analysis [HR 0.99 (95% CI 0.60-1.65), p = 0.99]. Male gender (HR 2.01, p = 0.01) and PS ≥ 2 (HR 3.28, p < 0.001) were found to be negative independent predictive factors for OS. CONCLUSION: Younger patients, those with symptomatic disease and brain metastases were more likely to be proposed CT-IO. However, sparing the chemotherapy in first-line does not appear to impact survival outcomes, even regarding early deaths.


Assuntos
Antineoplásicos Imunológicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Masculino , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Platina/uso terapêutico , Antígeno B7-H1/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Estudos Retrospectivos
4.
Tissue Antigens ; 84(3): 285-92, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25040134

RESUMO

Genetic matching for loci in the human leukocyte antigen (HLA) region between a donor and a patient in hematopoietic stem cell transplantation (HSCT) is critical to outcome; however, methods for HLA genotyping of donors in unrelated stem cell registries often yield results with allelic and phase ambiguity and/or do not query all clinically relevant loci. We present and evaluate a statistical method for in silico imputation of HLA alleles and haplotypes in large ambiguous population data from the Be The Match(®) Registry. Our method builds on haplotype frequencies estimated from registry populations and exploits patterns of linkage disequilibrium (LD) across HLA haplotypes to infer high resolution HLA assignments. We performed validation on simulated and real population data from the Registry with non-trivial ambiguity content. While real population datasets caused some predictions to deviate from expectation, validations still showed high percent recall for imputed results with average recall >76% when imputing HLA alleles from registry data. We simulated ambiguity generated by several HLA genotyping methods to evaluate the imputation performance on several levels of typing resolution. On average, imputation percent recall of allele-level HLA haplotypes was >95% for allele-level typing, >92% for intermediate resolution typing and >58% for serology (low-resolution) typing. Thus, allele-level HLA assignments can be imputed through the application of a set of statistical and population genetics inferences and with knowledge of haplotype frequencies and self-identified race and ethnicities.


Assuntos
Etnicidade , Antígenos HLA/genética , Transplante de Células-Tronco Hematopoéticas , Teste de Histocompatibilidade/métodos , Alelos , Simulação por Computador/estatística & dados numéricos , Frequência do Gene , Loci Gênicos/genética , Genótipo , Haplótipos , Teste de Histocompatibilidade/estatística & dados numéricos , Humanos , Desequilíbrio de Ligação , Modelos Genéticos , Sistema de Registros , Doadores de Tecidos , Estados Unidos
5.
Tissue Antigens ; 83(1): 17-26, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24355004

RESUMO

In order to study the impact of human leucocyte antigen (HLA) polymorphism distribution in identifying a matched haematopoietic stem cells unrelated donor (UD), we performed a multi-centric retrospective analysis with the aim of comparing the HLA-A, HLA-B, HLA-C, HLA-DRB1 and HLA-DQB1 phenotypes of 2126 patients (772 patients for whom a donor search failed to identify a matched UD, and 1354 patients who received a 10/10 allele level matched UD). Our results showed that rare HLA-C is often responsible for difficulty in identifying a donor. This locus may add a degree of complexity to a supposed 'frequent' HLA-A HLA-B and HLA-DRB1 phenotype, turning this phenotype into a less frequent one. For example, 32.5% of the phenotypes in the non-transplanted patients could not be explained by any of the pairs of known HLA-A, HLA-B, HLA-C and HLA-DRB1 haplotypes while this percentage dropped to less than 2% if combinations of only HLA-A, HLA-B and HLA-DRB1 haplotypes were considered. Such situations can be anticipated by computing an index, based on HLA haplotype frequency, the average registry sample size (ARS). ARS is defined as the inverse of the phenotype frequency computed using all corresponding pairs of haplotype frequencies. ARS confirmed that the most significant difference between transplanted and non-transplanted patients was correlated with the introduction of the locus HLA-C in the analysis (median: 8.3e + 4 vs 3.1e + 6, P < 0.0001). The higher the ARS the lower the likelihood of finding a 10/10 match UD reflecting the rareness of the patient's HLA. The area under receiver operator characteristics (AUROC) values of the ARS computation for HLA-A, HLA-B and HLA-DRB1 was 0.82 (0.80; 0.84) at a low-resolution level (two digits). Overall, our study promotes the use of haplotype frequency-based computations to develop computer-assisted donor search.


Assuntos
Simulação por Computador , Seleção do Doador/métodos , Antígenos HLA/imunologia , Transplante de Células-Tronco Hematopoéticas , Adulto , Tomada de Decisões Assistida por Computador , Feminino , Frequência do Gene , Antígenos HLA/genética , Histocompatibilidade , Humanos , Masculino , Fenótipo , Probabilidade , Prognóstico , Estudos Retrospectivos , Doadores de Tecidos , Adulto Jovem
6.
Tissue Antigens ; 82(2): 93-105, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23849067

RESUMO

Estimation of human leukocyte antigen (HLA) haplotype frequencies from unrelated stem cell donor registries presents a challenge because of large sample sizes and heterogeneity of HLA typing data. For the 14th International HLA and Immunogenetics Workshop, five bioinformatics groups initiated the 'Registry Diversity Component' aiming to cross-validate and improve current haplotype estimation tools. Five datasets were derived from different donor registries and then used as input for five different computer programs for haplotype frequency estimation. Because of issues related to heterogeneity and complexity of HLA typing data identified in the initial phase, the same five implementations, and two new ones, were used on simulated datasets in a controlled experiment where the correct results were known a priori. These datasets contained various fractions of missing HLA-DR modeled after European haplotype frequencies. We measured the contribution of sampling fluctuation and estimation error to the deviation of the frequencies from their true values, finding equivalent contributions of each for the chosen samples. Because of patient-directed activities, selective prospective typing strategies and the variety and evolution of typing technology, some donors have more complete and better HLA data. In this setting, we show that restricting estimation to fully typed individuals introduces biases that could be overcome by including all donors in frequency estimation. Our study underlines the importance of critical review and validation of tools in registry-related activity and provides a sustainable framework for validating the computational tools used. Accurate frequencies are essential for match prediction to improve registry operations and to help more patients identify suitably matched donors.


Assuntos
Antígenos HLA/imunologia , Haplótipos/imunologia , Teste de Histocompatibilidade/normas , Modelos Estatísticos , Sistema de Registros , Software/normas , Transplante de Células-Tronco , Frequência do Gene , Antígenos HLA/genética , Teste de Histocompatibilidade/métodos , Teste de Histocompatibilidade/estatística & dados numéricos , Humanos , Doadores não Relacionados/estatística & dados numéricos
7.
Rev Mal Respir ; 28(3): 328-35, 2011 Mar.
Artigo em Francês | MEDLINE | ID: mdl-21482336

RESUMO

INTRODUCTION: Bronchial colonisation is frequently reported in patients with lung cancer. These colonisations could influence patient therapeutic management and prognosis. The aim of our study is refine incidence and nature of bronchial colonisations in patients presenting with lung cancer. METHODS: Three hundred and eighty-eight patients with lung cancer underwent a flexible bronchoscopy at the time of diagnosis. Among them, 216 patients had a bacteriological, mycobacteriological and fungal investigation. Type and frequency of these colonisations were analyzed. RESULTS: Potential pathogens were found in 39.8% of samples, including mainly 39.8% of Gram-negative bacilli (Haemophilus influenzae, Enterobacter sp., Escherichia coli). In addition, we found 0.9% of mycobacteria and 13.9% of Candida albicans. Among these 216 patients where microbiological analysis was performed, patient features and tumor stage were not significantly correlated to microbial colonisation. CONCLUSIONS: Colonisation of airways is frequently reported when a lung cancer is diagnosed. Our data suggest that bronchial colonisation should be prospectively collected due to its potential interest in the management of lung cancer patients.


Assuntos
Adenocarcinoma/complicações , Brônquios/microbiologia , Bronquite/microbiologia , Líquido da Lavagem Broncoalveolar/microbiologia , Infecções por Bactérias Gram-Negativas/complicações , Infecções por Bactérias Gram-Positivas/complicações , Neoplasias Pulmonares/complicações , Broncoscopia , Candida albicans/isolamento & purificação , Candidíase/complicações , Feminino , França/epidemiologia , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/epidemiologia , Bactérias Gram-Positivas/isolamento & purificação , Infecções por Bactérias Gram-Positivas/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Fumar/efeitos adversos
8.
J Eur Acad Dermatol Venereol ; 24 Suppl 2: 23-30, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20443997

RESUMO

INTRODUCTION: Many epidemiological studies have associated psoriasis with an increased risk of coronary artery disease, resulting from a higher prevalence of cardiovascular risk factors in psoriasis patients compared with unmatched controls. However, the results of epidemiological studies vary depending upon the populations studied. The aim of this systemic review was to evaluate the risk of diabetes, hypertension, dyslipidaemia and obesity in adults with plaque psoriasis. In addition, we assessed the relationship between the risk of cardiovascular risk factors and psoriasis severity. METHODS: A systematic search was performed on Pubmed, Cochrane and Embase databases, using the key-words 'psoriasis', 'diabetes', 'hypertension', 'high blood pressure', 'dyslipidaemia', 'metabolic syndrome' and 'obesity', during the period from 1980 to June 2009. RESULTS: The initial literature search identified 353 articles. The final selection included 18 cross-sectional case-control studies. An increased risk of metabolic syndrome was observed in psoriatic patients (OR = 1.3-5.92), and a trend for a higher risk of obesity (OR = 1.18-5.49), especially in patients with severe psoriasis. For hypertension, hypertriglyceridaemia, and diabetes, the association was not significant in all studies. DISCUSSION: There was important heterogeneity in study design preventing from pooling results. Most often lifestyle factors such as smoking, alcohol consumption, physical activities were not taken into account. CONCLUSION: There is an increased risk of obesity and metabolic syndrome in psoriasis. For hypertension, diabetes and dyslipidaemia no consistency was found across studies. Prospective epidemiological studies with thorough recording of cardiovascular risk factors are required in psoriasis patients.


Assuntos
Doenças Cardiovasculares , Psoríase/complicações , Medição de Risco/métodos , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Europa (Continente)/epidemiologia , Humanos , Incidência , Estilo de Vida , Prognóstico , Psoríase/diagnóstico , Fatores de Risco
9.
J Eur Acad Dermatol Venereol ; 24 Suppl 2: 31-5, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20443998

RESUMO

OBJECTIVE: The aim of this study was to determine the prevalence of psoriatic arthritis (PsA) in the patients with plaque psoriasis and to give recommendation for the diagnosis of PsA for dermatologists. METHODS: A systematic search was performed in Pubmed, Cochrane and Embase databases. The key-words used from the Medical Searching Heading (MeSH) were: 'Psoriasis', 'Arthritis, Psoriatic', 'Uveitis' and 'Dactylitis'. We selected cross-sectional epidemiological studies written in English or French between January 1980 and October 2009. RESULTS: The initial literature search identified 2171 references. Based on abstract reading and exclusion of studies not written in English or French, and without control group, the final selection included 20 epidemiological studies. With the eight studies using rheumatologically validated criteria, the prevalence of PsA among psoriasis patient spanned a wide range from 7% to 26%. CONCLUSION: Psoriasis arthritis may affect up to 24% of psoriasis patients. Dermatologist should be aware of main clinical sign of PsA to promote earlier recognition and treatment of PsA.


Assuntos
Artrite Psoriásica/epidemiologia , Dermatologia/métodos , Medição de Risco/métodos , Artrite Psoriásica/diagnóstico , Progressão da Doença , Europa (Continente)/epidemiologia , Humanos , Prevalência , Fatores de Risco
10.
Oncogene ; 29(6): 876-87, 2010 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-19901968

RESUMO

Colorectal cancer is one of the most frequent cancers worldwide. As the tumor-node-metastasis (TNM) staging classification does not allow to predict the survival of patients in many cases, additional prognostic factors are needed to better forecast their outcome. Genes involved in DNA replication may represent an underexplored source of such prognostic markers. Indeed, accidents during DNA replication can trigger 'replicative stress', one of the main features of cancer from earlier stages onward. In this study, we assessed the expression of 47 'DNA replication' genes in primary tumors and adjacent normal tissues from a homogeneous series of 74 patients. We found that genes coding for translesional (TLS) DNA polymerases, initiation of DNA replication, S-phase signaling and protection of replication forks were significantly deregulated in tumors. We also observed that the overexpression of either the MCM7 helicase or the TLS DNA polymerase POLQ (if also associated with a concomitant overexpression of firing genes) was significantly related to poor patient survival. Our data suggest the existence of a 'DNA replication signature' that might represent a source of new prognostic markers. Such a signature could help in understanding the molecular mechanisms underlying tumor progression in colorectal cancer patients.


Assuntos
Neoplasias Colorretais/patologia , Replicação do DNA , Progressão da Doença , Proteínas de Ciclo Celular/genética , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Proteínas de Ligação a DNA/genética , DNA Polimerase Dirigida por DNA/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Componente 7 do Complexo de Manutenção de Minicromossomo , Família Multigênica , Proteínas Nucleares/genética , Prognóstico , DNA Polimerase teta
11.
Tissue Antigens ; 73(6): 553-60, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19493232

RESUMO

We have analysed the frequency of killer immunoglobulin-like receptors (KIR) in cohorts of patients from Turkey with acute lymphocyte leukaemia (n = 52), acute myeloid leukaemia (n = 54) and chronic myeloid leukaemia (CML) (n = 52) and compared the results with 154 controls. We also examined the frequencies of human leucocyte antigen (HLA)-C groups, -Bw4, -Bw6 and where appropriate the combination of the KIR gene and its ligand. We found several statistically significant results between the patients and the controls. We proposed a model in CML of protection via KIR2DL2 and/or KIR2DS2 with the presence of the ligand HLA-C1 group and susceptibility via HLA-Bw4 homozygosity (i.e. absence of HLA-Bw6).


Assuntos
Predisposição Genética para Doença , Antígenos HLA-C/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Receptores KIR2DL2/genética , Receptores KIR/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Frequência do Gene , Genótipo , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Adulto Jovem
12.
Oncogene ; 28(12): 1506-17, 2009 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-19169279

RESUMO

The Tip60 histone acetyltransferase belongs to a multimolecular complex that contains many chromatin remodeling enzymes including the ATPase p400, a protein involved in nucleosomal incorporation of specific histone variants and that can directly or indirectly repress some Tip60-dependent pathways. Tip60 activity is critical for the cellular response to DNA damage and is affected during cancer progression. Here, we found that the ratio between Tip60 and p400 mRNAs is affected in most colorectal carcinoma. Strikingly, reversing the p400/Tip60 imbalance by Tip60 overexpression or the use of siRNAs resulted in increased apoptosis and decreased proliferation of colon-cancer-derived cells, suggesting that this ratio defect is important for cancer progression. Furthermore, we demonstrate that the p400/Tip60 ratio controls the oncogene-induced DNA damage response, a known anticancer barrier. Finally, we found that it is also critical for the response to 5-fluorouracil, a first-line treatment against colon cancer. Together, our data indicate that the p400/Tip60 ratio is critical for colon cancer cells proliferation and response to therapeutic drugs through the control of stress-response pathways.


Assuntos
Neoplasias Colorretais/patologia , Dano ao DNA , DNA Helicases/fisiologia , Proteínas de Ligação a DNA/fisiologia , Histona Acetiltransferases/fisiologia , Apoptose , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Fluoruracila/farmacologia , Células HCT116 , Células HT29 , Histona Acetiltransferases/genética , Humanos , Lisina Acetiltransferase 5 , RNA Mensageiro/análise , Proteína Supressora de Tumor p53/fisiologia
13.
Oncogene ; 27(47): 6093-101, 2008 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-18622427

RESUMO

Cell cycle checkpoints and DNA repair act in concert to ensure DNA integrity during perturbation of normal replication or in response to genotoxic agents. Deficiencies in these protective mechanisms can lead to cellular transformation and ultimately tumorigenesis. Here we focused on Rev3, the catalytic subunit of the low-fidelity DNA repair polymerase zeta. Rev3 is believed to play a role in double-strand break (DSB)-induced DNA repair by homologous recombination. In line with this hypothesis, we show the accumulation of chromatin-bound Rev3 protein in late S-G2 of untreated cells and in response to clastogenic DNA damage as well as an gamma-H2AX accumulation in Rev3-depleted cells. Moreover, serine 995 of Rev3 is in vitro phosphorylated by the DSB-inducible checkpoint kinase, Chk2. Our data also disclose a significant reduction of rev3 gene expression in 74 colon carcinomas when compared to the normal adjacent tissues. This reduced expression is independent of the carcinoma stages, suggesting that the downregulation of rev3 might have occurred early during tumorigenesis.


Assuntos
Proteínas de Ligação a DNA/fisiologia , DNA Polimerase Dirigida por DNA/fisiologia , Proteínas Supressoras de Tumor/fisiologia , Domínio Catalítico , Células Cultivadas , Quinase do Ponto de Checagem 2 , Neoplasias do Colo/metabolismo , Quebras de DNA de Cadeia Dupla , Reparo do DNA , Replicação do DNA , Proteínas de Ligação a DNA/análise , Proteínas de Ligação a DNA/genética , DNA Polimerase Dirigida por DNA/análise , DNA Polimerase Dirigida por DNA/genética , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Humanos , Fosforilação , Proteínas Serina-Treonina Quinases/fisiologia , RNA Mensageiro/análise , Fase S
14.
Aliment Pharmacol Ther ; 27(12): 1261-8, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18397389

RESUMO

BACKGROUND: Hepatic venous pressure gradient (HVPG) is a prognostic marker in patients with cirrhosis. Transient elastography measures liver stiffness (LS). AIM: To assess the correlation between LS and HVPG and to investigate the performance of transient elastography for the diagnosis of significant portal hypertension (PHT). METHODS: Liver stiffness was measured by Fibroscan in 150 consecutive patients who underwent a liver biopsy with haemodynamic measurements. Usual clinical and biological data were collected. Significant PHT was defined as a HVPG > or = 10 mmHg. RESULTS: Hepatic venous pressure gradient was found to be > or = 10 mmHg in 76 patients. Cirrhosis was diagnosed in 89 patients. HVPG was found to be correlated with: LS (rho = 0.858; P < 0.001) and inversely correlated with prothrombin index (rho = -0.718; P < 0.001). Regarding significant PHT, AUROC for LS and prothrombin index were 0.945 [0.904-0.987] and 0.892 [0.837-0.947] respectively. The cut-off value of 21 kPa accurately predicted significant PHT in 92% of the 144 patients for whom LS was successful. CONCLUSION: Liver stiffness measurement is correlated with HVPG and transient elastography identifies patients with significant PHT.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Veias Hepáticas/fisiopatologia , Hipertensão Portal/diagnóstico , Cirrose Hepática/diagnóstico , Fígado/fisiologia , Veia Porta/fisiopatologia , Feminino , Hemodinâmica , Humanos , Hipertensão Portal/complicações , Hipertensão Portal/fisiopatologia , Cirrose Hepática/complicações , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Resultado do Tratamento
15.
Rev Epidemiol Sante Publique ; 55(4): 275-84, 2007 Aug.
Artigo em Francês | MEDLINE | ID: mdl-17597327

RESUMO

BACKGROUND: Availability of a healthy, human-leukocyte-antigen-matched hematopoietic stem cell source is a prerequisite for successful allogenic hematopoietic stem cell transplantation. In 70% of cases, the search of hematopoietic stem cells shifts from siblings to unrelated donor registries. Given that the Human Leucocytes Antigens (HLA) system is highly polymorphic and that the cost of HLA typing remains high, the adequacy between registry content and patient needs must be assessed. Registries should be optimally organized to increase the probability for any given patient to find a donor. METHODS: A welfare function associated with the existence of an HLA registry was defined as was a measure of the advantage for laboratories having performed HLA typing. We hypothesized a way to formalize registry efficiency and applied it to the French Hematopoietic Stem Cell donors Registry. RESULTS: The model determined an implicit value for the stem cell graft and showed that efficiency increased very slowly with increasing number of potential donors in registries. The optimal size of a registry was found to be sensitive to model parameters. CONCLUSION: Increased registry size, in terms of number of donors foreseeable in the French registry, would have a limited impact on registry efficiency and thus social effectiveness. Nevertheless, the calibration of the model justifies the goal of recruiting 100000 new volunteer donors over the next 10 years as proposed by the French government in the "Graft Plan". The policy of the regulatory agency should be oriented towards improving the probability a compatible potential donor identified during a preliminary search would become an actual fully compatible donor and towards reducing the cost of typing.


Assuntos
Transplante de Células-Tronco Hematopoéticas/economia , Sistema de Registros/normas , Doadores de Tecidos , França , Teste de Histocompatibilidade/economia , Humanos , Modelos Teóricos , Fenótipo , Seguridade Social
16.
Tissue Antigens ; 66(4): 267-76, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16185321

RESUMO

Killer cell immunoglobulin-like receptors (KIRs) belong to a diverse family of natural killer (NK) cell receptors recognizing human leukocyte antigen (HLA) class I molecules. Due to this functional link, KIR molecules are expected to display a high polymorphism, such as their HLA ligands. Moreover, many studies conducted in mouse and human models have shown that NK-KIR receptors play an important role in haematopoietic stem cell transplantation (HSCT). A beneficial impact of peculiar KIR ligand (HLA) mismatching has been reported suggesting a role to this combinatory HLA-KIR polymorphism. It is thus important to investigate KIR diversity in various human populations. To this end, we used polymerase chain reaction-sequence-specific primers to evaluate KIR gene in five selected populations (France, Guadeloupe, Senegal, Finland and Réunion). Genotypic and haplotypic frequencies were computed, as well as genetic distances and dendrogram (phylip package). These data illustrate the genetic relationship of these five populations through the KIR polymorphism. Results revealed a wide diversity in KIR gene frequencies in Guadeloupe and Réunion, and a high specificity in Senegal. The obtained dendrogram indicated small genetic distances between France, Guadeloupe and Réunion as well as between France and Finland. Senegal showed a distant genetic relationship with the other countries and, interestingly, an inverted ratio of coding/non-coding (KIR2DS4/1D) alleles compared with Caucasians. These data expose the broad diversity in KIR genes worldwide and show that KIR genes are pertinent tools in human population genetics. If the role of KIR donor-recipient incompatibilities is confirmed, KIR diversity according to ethnicity should be taken into account during the selection of HSCT donors.


Assuntos
Alelos , Frequência do Gene/genética , Polimorfismo Genético/genética , Receptores Imunológicos/genética , Feminino , Finlândia , França , Frequência do Gene/imunologia , Genética Populacional/métodos , Genótipo , Guadalupe , Antígenos HLA/genética , Antígenos HLA/imunologia , Humanos , Masculino , Polimorfismo Genético/imunologia , Receptores Imunológicos/imunologia , Receptores KIR , Reunião , Senegal
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