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1.
Environ Sci Pollut Res Int ; 31(16): 24014-24041, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38438639

RESUMO

This study contributes significantly to the field by utilising the World Economic Policy Uncertainty (WEPU) Index, as devised by (Ahir in Nat Bureau Econ Res 2022), to scrutinise its impact on carbon dioxide emission reporting and performance. Employing the generalised method of moments (GMM) on a substantial dataset of 604 Fortune Global 500 firms spanning from 2005 to 2020, our analysis reveals crucial insights. The research elucidates the dual influence of WEPU Index: a positive correlation with carbon dioxide emission reporting and a negative correlation aimed at mitigating adverse effects and promoting sustainable practices, thereby enhancing firm trust. Moreover, the findings shed light on how companies in emission-intensive industries tend to ramp up carbon dioxide emission reporting, potentially to bolster investor confidence, particularly during high WEPU Index periods. Furthermore, this study uncovers a compelling association between high emitters and lowered carbon dioxide emission performance, stemming from political and social pressures to integrate environmental considerations. Notably, this pressure intensifies during periods of increased WEPU Index. The empirical results presented in this study carry immediate practical implications. Specifically, they offer valuable insights for regulatory bodies and industry associations, guiding the development of enhanced environmental and social reporting regulations and guidelines, particularly concerning carbon emission reporting and performance.


Assuntos
Allium , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Dióxido de Carbono , Incerteza , Indústrias , Desenvolvimento Econômico
2.
J Econ Asymmetries ; 28: e00317, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37325185

RESUMO

This paper investigates the relationship between investors' attention, as measured by Google search queries, and equity implied volatility during the COVID-19 outbreak. Recent studies show that search investors' behavior data is an extremely abundant repository of predictive data, and investor-limited attention increases when the uncertainty level is high. Our study using data from thirteen countries across the globe during the first wave of the COVID-19 pandemic (January-April 2020) examines whether the search "topic and terms" for the pandemic affect market participants' expectations about future realized volatility. With the panic and uncertainty about COVID-19, our empirical findings show that increased internet searches during the pandemic caused the information to flow into the financial markets at a faster rate and thus resulting in higher implied volatility directly and via the stock return-risk relation. More specifically for the latter, the leverage effect in the VIX becomes stronger as Google search queries intensify. Both the direct and indirect effects on implied volatility, highlight a risk-aversion channel that operates during the pandemic. We also find that these effects are stronger in Europe than in the rest of the world. Moreover, in a panel vector autoregression framework, we show that a positive shock on stock returns may soothe COVID-related Google searches in Europe. Our findings suggest that Google-based attention to COVID-19 leads to elevated risk aversion in stock markets.

3.
BMC Med Genomics ; 14(1): 105, 2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33853586

RESUMO

BACKGROUND: Tumor molecular profile analysis by Next Generation Sequencing technology is currently widely applied in clinical practice and has enabled the detection of predictive biomarkers of response to targeted treatment. In parallel with targeted therapies, immunotherapies are also evolving, revolutionizing cancer therapy, with Programmed Death-ligand 1 (PD-L1), Microsatellite instability (MSI), and Tumor Mutational Burden (TMB) analysis being the biomarkers employed most commonly. METHODS: In the present study, tumor molecular profile analysis was performed using a 161 gene NGS panel, containing the majority of clinically significant genes for cancer treatment selection. A variety of tumor types have been analyzed, including aggressive and hard to treat cancers such as pancreatic cancer. Besides, the clinical utility of immunotherapy biomarkers (TMB, MSI, PD-L1), was also studied. RESULTS: Molecular profile analysis was conducted in 610 cancer patients, while in 393 of them a at least one biomarker for immunotherapy response was requested. An actionable alteration was detected in 77.87% of the patients. 54.75% of them received information related to on-label or off-label treatment (Tiers 1A.1, 1A.2, 2B, and 2C.1) and 21.31% received a variant that could be used for clinical trial inclusion. The addition to immunotherapy biomarker to targeted biomarkers' analysis in 191 cases increased the number of patients with an on-label treatment recommendation by 22.92%, while an option for on-label or off-label treatment was provided in 71.35% of the cases. CONCLUSIONS: Tumor molecular profile analysis using NGS is a first-tier method for a variety of tumor types and provides important information for decision making in the treatment of cancer patients. Importantly, simultaneous analysis for targeted therapy and immunotherapy biomarkers could lead to better tumor characterization and offer actionable information in the majority of patients. Furthermore, our data suggest that one in two patients may be eligible for on-label ICI treatment based on biomarker analysis. However, appropriate interpretation of results from such analysis is essential for implementation in clinical practice and accurate refinement of treatment strategy.


Assuntos
Imunoterapia , Instabilidade de Microssatélites , Adulto , Antígeno B7-H1 , Biomarcadores Tumorais , Humanos , Masculino
4.
Financ Res Lett ; 38: 101852, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36569650

RESUMO

We investigate the impact of the recent COVID-19 pandemic on the time-varying correlation between stock and bond returns. Using daily data on bond and stock returns for ten countries, covering Europe, Asia, US and Australia regions, we identify flight-to-quality episodes during the COVID-19 global pandemic crisis employing both a panel data specification and a wavelet analysis. Our empirical results demonstrate that flights occur simultaneously across countries and are not country-specific events. This finding suggests that the two largest asset classes offered diversification to investors during the recent crisis, when they actually needed it the most.

5.
Heliyon ; 6(12): e05715, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33354633

RESUMO

This study investigates the dynamic connectedness across the variance risk premium in international developed and emerging equity markets based on a Bayesian time-varying parameter vector autoregressive methodology. The empirical results indicate that the total spillover index is on average 65.6%, indicating a high, albeit declining, level of interconnectedness across the investor sentiment in the three markets under review until early 2020. Following the COVID-19 outbreak though, the total investors' risk aversion connectedness - as expected - strengthens, but more importantly, its dynamics alter, indicating that the risk aversion of emerging markets is an important contributor to the connectedness of international markets.

6.
JAMA Neurol ; 74(4): 459-469, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28241268

RESUMO

IMPORTANCE: Autologous hematopoietic stem cell transplantation (AHSCT) may be effective in aggressive forms of multiple sclerosis (MS) that fail to respond to standard therapies. OBJECTIVE: To evaluate the long-term outcomes in patients who underwent AHSCT for the treatment of MS in a large multicenter cohort. DESIGN, SETTING, AND PARTICIPANTS: Data were obtained in a multicenter, observational, retrospective cohort study. Eligibility criteria were receipt of AHSCT for the treatment of MS between January 1995 and December 2006 and the availability of a prespecified minimum data set comprising the disease subtype at baseline; the Expanded Disability Status Scale (EDSS) score at baseline; information on the administered conditioning regimen and graft manipulation; and at least 1 follow-up visit or report after transplant. The last patient visit was on July 1, 2012. To avoid bias, all eligible patients were included in the analysis regardless of their duration of follow-up. Data analysis was conducted from September 1, 2014 to April 27, 2015. EXPOSURES: Demographic, disease-related, and treatment-related exposures were considered variables of interest, including age, disease subtype, baseline EDSS score, number of previous disease-modifying treatments, and intensity of the conditioning regimen. MAIN OUTCOMES AND MEASURES: The primary outcomes were MS progression-free survival and overall survival. The probabilities of progression-free survival and overall survival were calculated using Kaplan-Meier survival curves and multivariable Cox proportional hazards regression analysis models. RESULTS: Valid data were obtained from 25 centers in 13 countries for 281 evaluable patients, with median follow-up of 6.6 years (range, 0.2-16 years). Seventy-eight percent (218 of 281) of patients had progressive forms of MS. The median EDSS score before mobilization of peripheral blood stem cells was 6.5 (range, 1.5-9). Eight deaths (2.8%; 95% CI, 1.0%-4.9%) were reported within 100 days of transplant and were considered transplant-related mortality. The 5-year probability of progression-free survival as assessed by the EDSS score was 46% (95% CI, 42%-54%), and overall survival was 93% (95% CI, 89%-96%) at 5 years. Factors associated with neurological progression after transplant were older age (hazard ratio [HR], 1.03; 95% CI, 1.00-1.05), progressive vs relapsing form of MS (HR, 2.33; 95% CI, 1.27-4.28), and more than 2 previous disease-modifying therapies (HR, 1.65; 95% CI, 1.10-2.47). Higher baseline EDSS score was associated with worse overall survival (HR, 2.03; 95% CI, 1.40-2.95). CONCLUSIONS AND RELEVANCE: In this observational study of patients with MS treated with AHSCT, almost half of them remained free from neurological progression for 5 years after transplant. Younger age, relapsing form of MS, fewer prior immunotherapies, and lower baseline EDSS score were factors associated with better outcomes. The results support the rationale for further randomized clinical trials of AHSCT for the treatment of MS.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Esclerose Múltipla/cirurgia , Resultado do Tratamento , Adolescente , Adulto , Criança , Estudos de Coortes , Avaliação da Deficiência , Intervalo Livre de Doença , Feminino , Humanos , Cooperação Internacional , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Transplante Autólogo , Adulto Jovem
7.
JAMA ; 311(24): 2490-8, 2014 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-25058083

RESUMO

IMPORTANCE: High-dose immunosuppressive therapy and autologous hematopoietic stem cell transplantation (HSCT) have shown efficacy in systemic sclerosis in phase 1 and small phase 2 trials. OBJECTIVE: To compare efficacy and safety of HSCT vs 12 successive monthly intravenous pulses of cyclophosphamide. DESIGN, SETTING, AND PARTICIPANTS: The Autologous Stem Cell Transplantation International Scleroderma (ASTIS) trial, a phase 3, multicenter, randomized (1:1), open-label, parallel-group, clinical trial conducted in 10 countries at 29 centers with access to a European Group for Blood and Marrow Transplantation-registered transplant facility. From March 2001 to October 2009, 156 patients with early diffuse cutaneous systemic sclerosis were recruited and followed up until October 31, 2013. INTERVENTIONS: HSCT vs intravenous pulse cyclophosphamide. MAIN OUTCOMES AND MEASURES: The primary end point was event-free survival, defined as time from randomization until the occurrence of death or persistent major organ failure. RESULTS: A total of 156 patients were randomly assigned to receive HSCT (n = 79) or cyclophosphamide (n = 77). During a median follow-up of 5.8 years, 53 events occurred: 22 in the HSCT group (19 deaths and 3 irreversible organ failures) and 31 in the control group (23 deaths and 8 irreversible organ failures). During the first year, there were more events in the HSCT group (13 events [16.5%], including 8 treatment-related deaths) than in the control group (8 events [10.4%], with no treatment-related deaths). At 2 years, 14 events (17.7%) had occurred cumulatively in the HSCT group vs 14 events (18.2%) in the control group; at 4 years, 15 events (19%) had occurred cumulatively in the HSCT group vs 20 events (26%) in the control group. Time-varying hazard ratios (modeled with treatment × time interaction) for event-free survival were 0.35 (95% CI, 0.16-0.74) at 2 years and 0.34 (95% CI, 0.16-0.74) at 4 years. CONCLUSIONS AND RELEVANCE: Among patients with early diffuse cutaneous systemic sclerosis, HSCT was associated with increased treatment-related mortality in the first year after treatment. However, HCST conferred a significant long-term event-free survival benefit. TRIAL REGISTRATION: isrctn.org Identifier: ISRCTN54371254.


Assuntos
Ciclofosfamida/administração & dosagem , Transplante de Células-Tronco Hematopoéticas , Imunossupressores/administração & dosagem , Esclerodermia Difusa/tratamento farmacológico , Adulto , Autoenxertos , Ciclofosfamida/efeitos adversos , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Imunossupressores/efeitos adversos , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida
8.
Ann Rheum Dis ; 71(10): 1733-40, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22586171

RESUMO

OBJECTIVE: The role of mesenchymal stem cells (MSC) in experimental arthritis is undoubtedly conflicting. This study explored the effect of bone marrow-derived MSC in previously untested and pathogenetically different models of rheumatoid arthritis (RA). METHODS: MSC were tested both in an induced (adjuvant-induced) and a spontaneous (K/BxN) arthritis model. Arthritis was assessed clinically and histologically. The proliferation of splenocytes and fibroblast-like synoviocytes (FLS) in the presence of MSC was measured by radioactivity incorporation. Toll-like receptor (TLR) expression was measured by real-time PCR. T-regulatory cell (Treg) frequency, T-cell apoptosis and cytokine secretion were monitored by flow cytometry. RESULTS: MSC, in vitro, strongly inhibited critical cell populations; splenocytes and FLS. In contrast, MSC proved ineffective in vivo, unless they were administered before disease onset, an effect implying that the inflammatory arthritic milieu potentially abrogates MSC immunomodulatory properties. In order to alleviate inflammation before MSC infusion, the authors administered, at arthritis onset, a short course with a proteasome inhibitor, bortezomib, whereas MSC were infused when established disease was expected. The bortezomib plus MSC group demonstrated a significantly decreased arthritis score over arthritic, MSC-only, bortezomib-only groups, also confirmed by histology and immunohistochemistry. The bortezomib plus MSC combination restored TLR expression and Treg frequency in blood and normalised FLS and splenocyte proliferation, apoptosis and cytokine secretion. CONCLUSION: MSC lose their immunomodulatory properties when infused in the inflammatory micromilieu of autoimmune arthritis. Conditioning of the recipient with bortezomib alters the disease microenvironment enabling MSC to modulate arthritis. Should milieu limitations also operate in human disease, this approach could serve as a strategy to treat RA by MSC.


Assuntos
Antirreumáticos/administração & dosagem , Artrite Experimental/terapia , Artrite Reumatoide/terapia , Ácidos Borônicos/administração & dosagem , Transplante de Células-Tronco Mesenquimais/métodos , Pirazinas/administração & dosagem , Linfócitos T/imunologia , Animais , Artrite Experimental/imunologia , Artrite Reumatoide/imunologia , Bortezomib , Modelos Animais de Doenças , Citometria de Fluxo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew , Reação em Cadeia da Polimerase em Tempo Real
9.
Mol Ther ; 20(1): 230-8, 2012 01.
Artigo em Inglês | MEDLINE | ID: mdl-21952171

RESUMO

The safety and efficacy of hematopoietic stem cell (HSC) mobilization was investigated in adult splenectomized (SPL) and non-SPL patients with thalassemia major, in two clinical trials, using different mobilization modes: granulocyte-colony-stimulating factor (G-CSF)-alone, G-CSF following pretreatment with hydroxyurea (HU), plerixafor-alone. G-CSF-mobilization was both safe and effective in non-SPL patients. However, in SPL patients the procedure resulted in excessive response to G-CSF, expressed as early hyperleukocytosis necessitating significant dose reduction, and suboptimal CD34(+) cells yields. One-month HU-pretreatment prevented hyperleukocytosis and allowed successful CD34(+) cell collections when an optimal washout period was maintained, but it significantly prolonged the mobilization procedure. Plerixafor resulted in rapid and effective mobilization in both SPL and non-SPL patients and was well-tolerated. For gene therapy of thalassemia, G-CSF or Plerixafor could be used as mobilization agents in non-SPL patients whereas Plerixafor appears to be the mobilization agent of choice in SPL adult thalassemics in terms of safety and efficacy.


Assuntos
Terapia Genética , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Mobilização de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco Hematopoéticas , Compostos Heterocíclicos/uso terapêutico , Esplenectomia , Talassemia beta/terapia , Adulto , Antígenos CD34/metabolismo , Benzilaminas , Ciclamos , Feminino , Fator Estimulador de Colônias de Granulócitos/efeitos adversos , Humanos , Hidroxiureia/uso terapêutico , Imunofenotipagem , Contagem de Leucócitos , Leucocitose/etiologia , Masculino , Esplenectomia/efeitos adversos , Resultado do Tratamento , Adulto Jovem
10.
Blood ; 118(6): 1693-8, 2011 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-21596847

RESUMO

To specify the incidence and risk factors for secondary autoimmune diseases (ADs) after HSCT for a primary AD, we retrospectively analyzed AD patients treated by HSCT reported to EBMT from 1995 to 2009 with at least 1 secondary AD (cases) and those without (controls). After autologous HSCT, 29 of 347 patients developed at least 1 secondary AD within 21.9 (0.6-49) months and after allogeneic HSCT, 3 of 16 patients. The observed secondary ADs included: autoimmune hemolytic anemia (n = 3), acquired hemophilia (n = 3), autoimmune thrombocytopenia (n = 3), antiphospholipid syndrome (n = 2), thyroiditis (n = 12), blocking thyroid-stimulating hormone receptor antibody (n = 1), Graves disease (n = 2), myasthenia gravis (n = 1), rheumatoid arthritis (n = 2), sarcoidosis (n = 2), vasculitis (n = 1), psoriasis (n = 1), and psoriatic arthritis (n = 1). After autologous HSCT for primary AD, the cumulative incidence of secondary AD was 9.8% ± 2% at 5 years. Lupus erythematosus as primary AD, and antithymocyte globulin use plus CD34(+) graft selection were important risk factors for secondary AD by multivariate analysis. With a median follow-up of 6.2 (0.54-11) years after autologous HSCT, 26 of 29 patients with secondary AD were alive, 2 died during their secondary AD (antiphospholipid syndrome, hemophilia), and 1 death was HSCT-related. This European multicenter study underlines the need for careful management and follow-up for secondary AD after HSCT.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/cirurgia , Transplante de Células-Tronco Hematopoéticas/métodos , Adolescente , Adulto , Anticorpos Monoclonais Murinos/uso terapêutico , Doenças Autoimunes/etiologia , Criança , Pré-Escolar , Ciclofosfamida/uso terapêutico , Europa (Continente) , Feminino , Glucocorticoides/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Fatores Imunológicos/uso terapêutico , Imunossupressores/uso terapêutico , Lactente , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prednisona/uso terapêutico , Estudos Retrospectivos , Fatores de Risco , Rituximab , Resultado do Tratamento , Adulto Jovem
12.
Haematologica ; 95(2): 284-92, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19773265

RESUMO

BACKGROUND: Autologous hematopoietic stem cell transplantation has been used since 1996 for the treatment of severe autoimmune diseases refractory to approved therapies. We evaluated the long-term outcomes of these transplants and aimed to identify potential prognostic factors. DESIGN AND METHODS: In this observational study we analyzed all first autologous hematopoietic stem cell transplants for autoimmune diseases reported to the European Group for Blood and Marrow Transplantation (EBMT) registry between 1996-2007. The primary end-points for analysis were overall survival, progression-free survival and transplant-related mortality at 100 days. RESULTS: Nine hundred patients with autoimmune diseases (64% female; median age, 35 years) who underwent a first autologous hematopoietic stem cell transplant were included. The main diseases were multiple sclerosis (n=345), systemic sclerosis (n=175), systemic lupus erythematosus (n=85), rheumatoid arthritis (n=89), juvenile arthritis (n=65), and hematologic immune cytopenia (n=37). Among all patients, the 5-year survival was 85% and the progression-free survival 43%, although the rates varied widely according to the type of autoimmune disease. By multivariate analysis, the 100-day transplant-related mortality was associated with the transplant centers' experience (P=0.003) and type of autoimmune disease (P=0.03). No significant influence of transplant technique was identified. Age less than 35 years (P=0.004), transplantation after 2000 (P=0.0015) and diagnosis (P=0.0007) were associated with progression-free survival. CONCLUSIONS: This largest cohort studied worldwide shows that autologous hematopoietic stem cell transplantation can induce sustained remissions for more than 5 years in patients with severe autoimmune diseases refractory to conventional therapy. The type of autoimmune disease, rather than transplant technique, was the most relevant determinant of outcome. Results improved with time and were associated with the transplant centers' experience. These data support ongoing and planned phase III trials to evaluate the place of autologous hematopoietic stem cell transplantation in the treatment strategy for severe autoimmune diseases.


Assuntos
Doenças Autoimunes/diagnóstico , Doenças Autoimunes/terapia , Transplante de Células-Tronco Hematopoéticas , Adolescente , Adulto , Idoso , Doenças Autoimunes/epidemiologia , Criança , Pré-Escolar , Estudos de Coortes , Intervalo Livre de Doença , Europa (Continente)/epidemiologia , Feminino , Transplante de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco Hematopoéticas/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Transplante Autólogo , Resultado do Tratamento , Adulto Jovem
13.
Hum Gene Ther ; 21(3): 299-310, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19795976

RESUMO

Granulocyte colony-stimulating factor (G-CSF)-mobilized blood stem cells may become the preferable source of hematopoietic stem cells (HSCs) for gene therapy because of the higher yield of cells compared with conventional bone marrow harvesting. A G-CSF-associated risk of splenic rupture has been recognized in normal donors of HSCs, but limited information is available about the G-CSF effect in the presence of splenomegaly and extramedullary hematopoiesis. We investigated the G-CSF effect in a thalassemic mouse model (HBB(th-3)) as compared with a normal strain (C57BL/6), in terms of safety, mobilization efficacy, and distribution of stem cells among hematopoietic compartments. There was no death or clinical sequelae of splenic rupture in G-CSF-treated animals of either strain; however, hemorrhagic infarcts in the spleen were detected with low frequency in G-CSF-treated HBB(th-3) mice (12.5%). HBB(th-3) mice mobilized less effectively than C57BL/6 mice (Lin(-)Sca-1(+)c-Kit(+) cells/microl of peripheral blood mononuclear cells [PBMCs]: 90 +/- 55 vs. 255 +/- 174, respectively, p = 0.01; CFU-GM/ml PBMCs: 390 +/- 262 vs. 1131 +/- 875, p = 0.01) because of increased splenic trapping of hematopoietic stem and progenitor cells (Lin(-)Sca-1(+)c-Kit(+) cells per spleen (x10(5)): 487 +/- 35 vs. 109 +/- 19.6, p = 0.01; CFU-GM per spleen (x10(2)): 1470 +/- 347 vs. 530 +/- 425, p = 0.0006). Splenectomy restored the mobilization proficiency of thalassemic mice at comparable levels to normal mice and resulted in the development of a hematopoietic compensatory mechanism in the thalassemic liver that protected splenectomized mice from severe anemia. Our data imply that, in view of human gene therapy for thalassemia, either multiple cycles or alternative ways of mobilization may be required for a sufficient yield of transplantable HSCs. In addition, strategies to minimize the risk of G-CSF-induced splenic infarcts should be explored in a clinical setting.


Assuntos
Terapia Genética , Fator Estimulador de Colônias de Granulócitos/farmacologia , Mobilização de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/metabolismo , Talassemia/terapia , Animais , Modelos Animais de Doenças , Citometria de Fluxo , Transplante de Células-Tronco Hematopoéticas , Hemoglobinas/fisiologia , Humanos , Técnicas Imunoenzimáticas , Fígado/metabolismo , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Recombinantes , Baço/metabolismo , Baço/patologia , Esplenectomia , Talassemia/genética , Talassemia/metabolismo
14.
Lancet Oncol ; 10(5): 489-500, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19345145

RESUMO

BACKGROUND: Procedures to prevent severe graft-versus-host disease (GVHD) delay immune reconstitution secondary to transplants of haploidentical haemopoietic stem cells for the treatment of leukaemia, leading to high rates of late infectious mortality. We aimed to systematically add back genetically engineered donor lymphocytes to facilitate immune reconstitution and prevent late mortality. METHODS: In a phase I-II, multicentre, non-randomised trial of haploidentical stem-cell transplantation, we infused donor lymphocytes expressing herpes-simplex thymidine kinase suicide gene (TK-cells) after transplantation. The primary study endpoint was immune reconstitution defined as circulating CD3+ count of 100 cells per muL or more for two consecutive observations. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00423124. FINDINGS: From Aug 13, 2002, to March 26, 2008, 50 patients (median age 51 years, range 17-66) received haploidentical stem-cell transplants for high-risk leukaemia. Immune reconstitution was not recorded before infusion of TK-cells. 28 patients received TK-cells starting 28 days after transplantation; 22 patients obtained immune reconstitution at median 75 days (range 34-127) from transplantation and 23 days (13-42) from infusion. Ten patients developed acute GVHD (grade I-IV) and one developed chronic GVHD, which were controlled by induction of the suicide gene. Overall survival at 3 years was 49% (95% CI 25-73) for 19 patients who were in remission from primary leukaemia at the time of stem-cell transplantation. After TK-cell infusion, the last death due to infection was at 166 days, this was the only infectious death at more than 100 days. No acute or chronic adverse events were related to the gene-transfer procedure. INTERPRETATION: Infusion of TK-cells might be effective in accelerating immune reconstitution, while controlling GVHD and protecting patients from late mortality in those who are candidates for haploidentical stem-cell transplantation. FUNDING: MolMed SpA, Italian Association for Cancer Research.


Assuntos
Genes Transgênicos Suicidas , Doença Enxerto-Hospedeiro/prevenção & controle , Antígenos HLA/imunologia , Histocompatibilidade , Transfusão de Linfócitos , Adolescente , Adulto , Idoso , Feminino , Técnicas de Transferência de Genes , Doença Enxerto-Hospedeiro/terapia , Haplótipos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Histocompatibilidade/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Simplexvirus/enzimologia , Timidina Quinase/genética , Condicionamento Pré-Transplante , Adulto Jovem
15.
Autoimmunity ; 41(8): 601-10, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18958762

RESUMO

High-dose immunosuppressive chemotherapy or total body irradiation followed by autologous transplantation of hemopoietic stem cells (ASCT) was introduced in the treatment of active, progressing, and therapy-resistant multiple sclerosis (MS) in 1995. Since then, more than 300 patients have undergone this sort of treatment worldwide and the European Group for Blood and Marrow Transplantation (EBMT) published on two occasions, in 2002 and in 2006, the results of collective analyses performed in 85 and in 183 cases, respectively. In most communications the results were reported favorable with some cases showing spectacular recoveries and also probabilities of long-lasting disease stability, between 60 and 80% at three years after transplant. Of great interest was the fact that magnetic resonance imaging studies invariably showed that the inflammation in the central nervous system resolved and gadolinium-enhancing lesions were completely abolished or markedly reduced. These results appear superior to those yielded by standard therapies but this superiority needs to be demonstrated by comparative studies, such as the EBMT-launched ASTIMS trial. Moreover, ASCT is a rather toxic procedure associated with a mortality risk of 2-3%. Therefore, it is not a treatment for the general population of MS patients but only for selected cases that do not respond to standard therapies and worsen rapidly, i.e. in situations where benefits are expected to counterbalance morbidity and mortality risks. Nevertheless, certain issues seem to have cleared up: ASCT should be used early, during the inflammatory phase of the disease; very high-intensity pre-transplant conditioning regimens increase toxicity but do not seem to increase efficacy compared to intermediate-intensity regimens; the results are dramatic and life-saving in resistant, so-called "malignant" cases; ASCT does not only cause debulking of autoreactive clones but it also brings about qualitative immunological changes that might eventually establish immunologic self-tolerance; the progression of brain atrophy appears to slow down with time; with the implementation of proper patient-selection criteria, the risks of morbidity and mortality can be minimized.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Imunossupressores/uso terapêutico , Esclerose Múltipla/terapia , Condicionamento Pré-Transplante/métodos , Progressão da Doença , Humanos , Imunossupressores/efeitos adversos , Condicionamento Pré-Transplante/efeitos adversos
16.
Blood Cells Mol Dis ; 41(2): 203-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18621559

RESUMO

Transcriptional and post-transcriptional control mechanisms have a differential impact on cellular physiology depending on activation status. Several lines of evidence suggest that chronic lymphocytic leukemia (CLL) malignant B cells resemble antigen-experienced and activated B cells. In the present study, we investigated the expression of transferrin receptor 1 (TfR1, CD71), one of the "classical" markers up-regulated upon B-cell activation, and TfR2, a novel receptor for transferrin, in peripheral blood CD19+ B cells from ten healthy individuals and 76 patients with CLL so as to gain insight into potential disease-related differences in underlying regulatory mechanisms. Marked differences in the production and expression of these receptors were detected in malignant but not in normal B cells. Specifically, TfR1 mRNA and protein levels were significantly higher in comparison to TfR2, both in normal and malignant B cells. Furthermore, discrepancies between TfR mRNA and protein expression were observed in CLL; in contrast, mRNA and protein expression levels were generally concordant in normal B cells. Exposure to actinomycin D decreased TfR1 and TfR2 mRNA levels in normal CD19+ B cells but had no effect on CLL malignant cells. The protein synthesis inhibitor cycloheximide had opposing effects in normal vs. CLL malignant B cells: thus, TfR1 and TfR2 mRNA levels were increased in normal B cells, whereas they were unaffected or even suppressed in CLL malignant B cells. These results allude to differential regulation of TfR1 and TfR2 expression in normal B cells vs. CLL. In normal B cells, transcriptional mechanisms exert a critical control over TfR1 and TfR2 expression, whereas in CLL post-transcriptional mechanisms seem to play a complementary and perhaps more important role. This type of control appears to be especially suited for modulation of genes implicated in proliferation of activated cells, like CLL malignant B cells.


Assuntos
Linfócitos B/química , Regulação Neoplásica da Expressão Gênica , Leucemia Linfocítica Crônica de Células B/patologia , Receptores da Transferrina/análise , Antígenos CD/análise , Antígenos CD/genética , Estudos de Casos e Controles , Cicloeximida/farmacologia , Dactinomicina/farmacologia , Humanos , RNA Mensageiro/análise , Receptores da Transferrina/genética , Regulação para Cima
18.
Haematologica ; 93(3): 473-4, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18310544

RESUMO

We report a remarkable association of recurrent (stereotyped) cytogenetic aberrations with two subsets of chronic lymphocytic leukemia (CLL) cases expressing IgG-switched, stereotyped B-cell receptors (BCRs). Comparison with cases with heterogeneous BCRs showed that these recurrent cytogenetic aberrations were subset-biased. These findings further support a role for antigen in CLL development.


Assuntos
Aberrações Cromossômicas , Regiões Determinantes de Complementaridade/genética , Imunoglobulina G/genética , Leucemia Linfocítica Crônica de Células B/genética , Proteínas de Neoplasias/genética , Receptores de Antígenos de Linfócitos B/genética , Humanos , Região de Troca de Imunoglobulinas , Leucemia Linfocítica Crônica de Células B/classificação , Leucemia Linfocítica Crônica de Células B/imunologia , Leucemia Linfocítica Crônica de Células B/patologia
19.
J Clin Oncol ; 25(31): 4938-45, 2007 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17909197

RESUMO

PURPOSE: To evaluate the role of donor lymphocyte infusion (DLI) in the treatment of relapsed acute myeloid leukemia (AML) after allogeneic hematopoietic stem cell transplantation (HSCT). PATIENTS AND METHODS: We retrospectively analyzed the data of 399 patients with AML in first hematological relapse after HSCT whose treatment did (n = 171) or did not (n = 228) include DLI. After correction for imbalances and established risk factors, the two groups were compared with respect to overall survival. Further, a detailed analysis of risk factors for survival among DLI recipients was performed. RESULTS: Median follow-up was 27 and 40 months, respectively. Estimated survival at 2 years (+/- standard deviation) was 21% +/- 3% for patients receiving DLI and 9% +/- 2% for patients not receiving DLI. After adjustment for differences between the groups, better outcome was associated with age younger than 37 years (P = .008), relapse occurring more than 5 months after HSCT (P < .0001), and use of DLI (P = .04). Among DLI recipients, a lower tumor burden at relapse (< 35% of bone marrow blasts; P = .006), female sex (P = .02), favorable cytogenetics (P = .004), and remission at time of DLI (P < .0001) were predictive for survival in a multivariate analysis. Two-year survival was 56% +/- 10%, if DLI was performed in remission or with favorable karyotype, and 15% +/- 3% if DLI was given in aplasia or with active disease. CONCLUSION: Although further evidence for a graft-versus-leukemia effect by DLI is provided, our results confirm, that the clinical benefit is limited to a minority of patients. Strategies to reduce tumor burden before DLI, as well as alternative treatment options should be investigated in adults with relapsed AML after HSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda/terapia , Transfusão de Linfócitos , Recidiva Local de Neoplasia/terapia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Falha de Tratamento , Resultado do Tratamento
20.
Biol Blood Marrow Transplant ; 13(9): 1049-56, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17697967

RESUMO

Immunized against hepatitis B virus (HBV) recipients are at risk of developing HBV postallogeneic stem cell transplantation because of the potential loss of their HBV immunity. The aim of the study was to evaluate: (1) the HbsAb eradication incidence posttransplant and potential risk factors, (2) the impact of donor's immunity on HbsAb loss, (3) the incidence of hepatitis B in patients with HbsAb disappearance. We studied, retrospectively, in 26 vaccinated and 56 naturally immunized recipients, the posttransplant HbsAb titers for a median period of 36 (6-132) months. The probability of HbsAb loss and HBV-related hepatitis was determined in all recipients. The impact of donor's immunity origin in the HBsAb disappearance was evaluated in the subgroup of, actively or naturally, immunized recipients/donors pairs. The 5-year probability of HbsAb disappearance was 90% for all patients with 18% probability of developing hepatitis at 12 years, for those who lost HbsAb. Marrow graft, antithymocyte globulin administration, age<30 years and chronic graft-versus-host disease were significant risk factors for HbsAb loss. In the subgroup of immunized recipients/donors, the donor's active immunization significantly affected this loss. Allotransplanted patients are at high risk of losing protection against HBV. The adoptive transfer of active HBV immunity does not seem to offer sustained protection posttransplant.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Vacinas contra Hepatite B , Vírus da Hepatite B/imunologia , Imunoterapia Ativa , Adolescente , Adulto , Criança , Feminino , Hepatite B/prevenção & controle , Anticorpos Anti-Hepatite B/sangue , Humanos , Imunoterapia Adotiva , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Transplante Homólogo , Falha de Tratamento
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