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1.
Nanoscale Adv ; 5(11): 3063-3074, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37260483

RESUMO

Well-organized, spherical, mesoporous hollow @CuMgAl-LDHs (layered double hydroxides) are prepared by the controlled removal of the SiO2 from SiO2@CuMgAl-LDH core-shell hybrids that in turn are synthesized via a bottom-up strategy. The materials are prepared with various Cu/Mg molar ratios (Cu/Mg = 0.05-0.50) while keeping the ratio of Cu and Mg constant, (Cu + Mg)/Al = 2. The effect of Cu doping and the silica core removal process (conducted for 4 h at 30 °C using 1 M NaOH) on the chemical composition, morphology, structure, texture and reducibility of the resulting materials are described. @CuMgAl-MOs (mixed oxides) obtained by thermal treatment of the @CuMgAl-LDHs are active and selective catalysts for the selective catalytic reduction of NOx using ammonia, and effectively operate at low temperatures. The N2 yield increases with increased Cu content in the CuMgAl shell, which is associated with the easier reducibility of the Cu species incorporated into the MgAl matrix. @CuMgAl-MOs show better catalytic performance than bulk CuMgAl MOs.

2.
Front Oncol ; 9: 644, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31380281

RESUMO

Introduction: The individualization of treatment is attractive, especially in children with high-risk cancer. In such a rare and very heterogeneous group of diseases, large population-based clinical randomized trials are not feasible without international collaboration. We therefore propose comparative patient series analysis in a real-life scenario. Methods: Open cohort observational study, comparative analysis. Seventy patients with high-risk solid tumors diagnosed between 2003 and 2015 and in whom the treatment was individualized either empirically or based on biomarkers were analyzed. The heterogeneity of the cohort and repeated measurements were advantageously utilized to increase effective sample size using appropriate statistical tools. Results: We demonstrated a beneficial effect of empirically given low-dose metronomic chemotherapy (HR 0.46 for relapses, p = 0.017) as well as various repurposed or targeted agents (HR 0.15 for deaths, p = 0.004) in a real-life scenario. However, targeted agents given on the basis of limited biological information were not beneficial. Conclusions: Comparative patient series analysis provides institutional-level evidence for treatment individualization in high-risk pediatric malignancies. Our findings emphasize the need for a comprehensive, multi omics assessment of the tumor and the host as well whenever molecularly driven targeted therapies are being considered. Low-dose metronomic chemotherapy or local control of the disease may be a more rational option in situations where targeted treatment cannot be justified by robust evidence and comprehensive biological information. "Targeted drugs" may be given empirically with a realistic benefit expectation when based on robust rationale.

5.
Ann Hematol ; 92(10): 1397-403, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23728608

RESUMO

Sequential use of chemotherapy and reduced-intensity conditioning (RIC) with allogeneic stem cell transplantation (SCT) has been proposed to improve the treatment outcomes in patients with high-risk acute myeloid leukemia (AML). Here, we present our experience with this procedure in a cohort of 60 AML patients with primary induction failure (n = 9); early, refractory, or ≥ second relapse (n = 41); or unfavorable cytogenetics (n = 10). A combination of fludarabine (30 mg/m²/day), cytarabine (2 g/m²/day), and amsacrine (100 mg/m²/day) for 4 days was used. After 3 days of rest, RIC was carried out, consisting of 4 Gy total body irradiation, antithymocyte globulin (ATG-Fresenius), and cyclophosphamide (fludarabine, amsacrine, and cytarabine (FLAMSA)-RIC protocol). Prophylactic donor lymphocyte infusions (pDLIs) were given in patients with complete remission (CR) and without evidence of graft-versus-host disease ≥120 days after SCT. The median time of neutrophil engraftment was 17 days. CR was achieved in 47 of 60 patients (78%). Eleven patients received pDLIs resulting in long-term CR in eight of them. Non-relapse mortality after 1 and 3 years was 25 and 28%, respectively. With a median follow-up of 37 months (range, 10-69), 3-year overall survival and 3-year progression-free survival were 42 and 33%, respectively. In a multivariate analysis, dose of CD34(+) cells >5 × 106/kg (p = 0.005; hazard ratio (HR) = 0.276), remission of AML before SCT (p = 0.044; HR = 0.421), and achievement of complete chimerism after SCT (p = 0.001; HR = 0.205) were significant factors of better overall survival. The use of the FLAMSA-RIC protocol in suitable high-risk AML patients results in a long-term survival rate of over 40%.


Assuntos
Amsacrina/uso terapêutico , Antimetabólitos Antineoplásicos/uso terapêutico , Citarabina/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/métodos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/terapia , Vidarabina/análogos & derivados , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica , Feminino , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Vidarabina/uso terapêutico , Adulto Jovem
6.
Ann Hematol ; 92(2): 249-54, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23014659

RESUMO

Allogeneic stem cell transplantation (SCT) is a treatment option for patients with poor-risk chronic lymphocytic leukemia (CLL). Sequential use of chemotherapy and reduced-intensity conditioning has been proposed to improve the treatment outcomes. Fludarabine (30 mg/m(2)/day) and cytarabine (2 g/m(2)/day) for 4 days (combination of fludarabine with cytarabine; FAraC) were used for cytoreduction. After 3 days of rest, reduced intensity conditioning (RIC) was carried out consisting of 4 Gy total body irradiation, 10-20 mg/kg/day antithymocyte globulin for 3 days, and 40-60 mg/kg/day cyclophosphamide for 2 days. The median time of neutrophil engraftment was 16 days. The most frequent toxicities were grades III/IV infections in 12 of 15 cases and gastrointestinal toxicities in 8 of 15 cases. Remission (complete remission + partial remission) was achieved in 14 of 15 patients (93 %), minimal residual disease negativity according to flowcytometric analysis was observed in 10 patients. Nonrelapse mortality after 1 and 2 years was 7 and 13 %, respectively. After the median follow-up from SCT of 30 months, 80 % of patients were alive (12/15), three patients have died, and three relapses occurred. The FAraC-RIC protocol seems to be a promising approach to the treatment of poor-risk CLL with a high response rate of 93 % and favorable progression-free survival and overall survival of 70 and 85 % at 2 years after SCT, respectively. Other prospective clinical trials are needed to confirm the results of this novel therapeutic strategy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Transplante de Células-Tronco de Sangue Periférico , Condicionamento Pré-Transplante/métodos , Adulto , Alemtuzumab , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Murinos/administração & dosagem , Transplante de Medula Óssea/efeitos adversos , Ciclofosfamida/administração & dosagem , Citarabina/administração & dosagem , Dexametasona/administração & dosagem , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Imunossupressores/uso terapêutico , Estimativa de Kaplan-Meier , Leucemia Linfocítica Crônica de Células B/cirurgia , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Transplante de Células-Tronco de Sangue Periférico/efeitos adversos , Prednisolona/administração & dosagem , Estudos Prospectivos , Recidiva , Risco , Rituximab , Terapia de Salvação , Condicionamento Pré-Transplante/efeitos adversos , Transplante Homólogo , Resultado do Tratamento , Vidarabina/administração & dosagem , Vidarabina/análogos & derivados , Vincristina/administração & dosagem , Irradiação Corporal Total
7.
BMC Med Genet ; 8: 32, 2007 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-17561994

RESUMO

BACKGROUND: Alterations in the highly penetrant cancer susceptibility gene BRCA1 are responsible for the majority of hereditary breast and/or ovarian cancers. However, the number of detected germline mutations has been lower than expected based upon genetic linkage data. Undetected deleterious mutations in the BRCA1 gene in some high-risk families could be due to the presence of intragenic rearrangements as deletions, duplications or insertions spanning whole exons. Standard PCR-based screening methods are mainly focused on detecting point mutations and small insertions/deletions, but large rearrangements might escape detection.The purpose of this study was to determine the type and frequency of large genomic rearrangements in the BRCA1 gene in hereditary breast and ovarian cancer cases in the Czech Republic. METHODS: Multiplex ligation-dependent probe amplification (MLPA) was used to examine BRCA1 rearrangements in 172 unrelated patients with hereditary breast and/or ovarian cancer syndrome without finding deleterious mutation after complete screening of whole coding regions of BRCA1/2 genes. Positive MLPA results were confirmed and located by long-range PCR. The breakpoints of detected rearrangements were characterized by sequencing. RESULTS: Six different large deletions in the BRCA1 gene were identified in 10 out of 172 unrelated high-risk patients: exons 1A/1B and 2 deletion; partial deletion of exon 11 and exon 12; exons 18 and 19 deletion; exon 20 deletion; exons 21 and 22 deletion; and deletion of exons 5 to 14. The breakpoint junctions were localized and further characterized. Destabilization and global unfolding of the mutated BRCT domains explain the molecular and genetic defects associated with the exon 20 in-frame deletion and the exon 21 and 22 in-frame deletion, respectively. CONCLUSION: Using MLPA, mutations were detected in 6% of high-risk patients previously designated as BRCA1/2 mutation-negative. The breakpoints of five out of six large deletions detected in Czech patients are novel. Screening for large genomic rearrangements in the BRCA1 gene in the Czech high-risk patients is highly supported by this study.


Assuntos
Neoplasias da Mama/genética , Rearranjo Gênico , Genes BRCA1 , Neoplasias Ovarianas/genética , Adulto , República Tcheca , DNA de Neoplasias , Feminino , Deleção de Genes , Mutação em Linhagem Germinativa , Humanos , Linhagem , Mutação Puntual , Reação em Cadeia da Polimerase , Síndrome
8.
Mol Genet Metab ; 89(4): 300-9, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16931086

RESUMO

Large gene deletions and duplications were analyzed in 59 unrelated phenylketonuria (PKU) patients negative for phenylalanine hydroxylase (PAH) mutations on one or both alleles from previous exon by exon analysis. Using the novel multiplex ligation-dependent probe amplification (MLPA) method, a total of 31 partial PAH deletions involving single exons were identified in 31 PKU patients. Nineteen cases exhibited deletion of exon 5, and 12 cases provided evidence for the deletion of exon 3. Subsequently, using restriction enzyme digestion and DNA sequencing, three different large deletions, EX3del4765 (12 cases), EX5del955 (2 cases) and EX5del4232ins268 (17 cases) were identified and confirmed by long-range PCR and by the analysis of aberrant transcripts. Altogether, the 31 large deletions presented account for 3% of all PAH mutant alleles investigated in Czech PKU patients. Bioinformatic analysis of three breakpoints showed that the mutation EX3del4765 had arisen through an Alu-Alu homologous recombination, whereas two other mutations-the EX5del955 and EX5del4232ins268, had been created by a non-homologous end joining (NHEJ). We conclude that MLPA is a convenient, rapid and reliable method for detection of intragenic deletions in the PAH gene and that a relatively high number of alleles with large deletions are present in the Slavic PKU population.


Assuntos
Reação em Cadeia da Ligase/métodos , Fenilalanina Hidroxilase/genética , Recombinação Genética , Sequência de Bases , Análise Mutacional de DNA , Éxons , Humanos , Íntrons , Dados de Sequência Molecular , Deleção de Sequência
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