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2.
Solid State Nucl Magn Reson ; 84: 137-142, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28209384

RESUMO

Solid state NMR is applied in this contribution on the xAl2O3-(50-x/2)Na2O-(50-x/2)P2O5 composition line (with 0

3.
Phys Chem Chem Phys ; 18(38): 26764-26770, 2016 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-27711426

RESUMO

The structure of the important technological glass Pyrex® was investigated by 1D- and 2D-correlation NMR techniques. Its local order was analysed in a first step by 1D 23Na, 27Al, 11B and 29Si MAS-NMR performed at 9.4 and 18.8 T. In a second step, its medium range order was documented using homo- and, for the first time, hetero-nuclear correlation NMR techniques: (i) the presence and the nature of BOB bonds were analysed using 2D 11B DQ-SQ map; (ii) the silicate speciation was probed using 2D 29Si/X (X = 11B, 23Na and 27Al) D-HMQC maps and (iii) the 27Al/11B interaction was studied using TRAPDOR-NMR experiments. Altogether, the set of NMR data was used to extract accurate NMR parameters, to rule out the presence of diborate and danburite superstructural units and to provide an updated structural model based on B3 based groups attached to a T4 network (T = Si, B, Al).

4.
Leukemia ; 30(4): 873-82, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26648534

RESUMO

The transcription factor forkhead box M1 (FOXM1) is a validated oncoprotein in solid cancers, but its role in malignant plasma cell tumors such as multiple myeloma (MM) is unknown. We analyzed publicly available MM data sets and found that overexpression of FOXM1 prognosticates inferior outcome in a subset (~15%) of newly diagnosed cases, particularly patients with high-risk disease based on global gene expression changes. Follow-up studies using human myeloma cell lines (HMCLs) as the principal experimental model system demonstrated that enforced expression of FOXM1 increased growth, survival and clonogenicity of myeloma cells, whereas knockdown of FOXM1 abolished these features. In agreement with that, constitutive upregulation of FOXM1 promoted HMCL xenografts in laboratory mice, whereas inducible knockdown of FOXM1 led to growth inhibition. Expression of cyclin-dependent kinase 6 (CDK6) and NIMA-related kinase 2 (NEK2) was coregulated with FOXM1 in both HMCLs and myeloma patient samples, suggesting interaction of these three genes in a genetic network that may lend itself to targeting with small-drug inhibitors for new approaches to myeloma therapy and prevention. These results establish FOXM1 as high-risk myeloma gene and provide support for the design and testing of FOXM1-targeted therapies specifically for the FOXM1(High) subset of myeloma.


Assuntos
Proliferação de Células , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Mieloma Múltiplo/patologia , Animais , Apoptose , Western Blotting , Proteína Forkhead Box M1 , Fatores de Transcrição Forkhead/genética , Humanos , Técnicas Imunoenzimáticas , Imunoprecipitação , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/mortalidade , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Phys Chem Chem Phys ; 17(44): 29531-40, 2015 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-26186677

RESUMO

The structure of tin borophosphate glasses, considered for the development of low temperature sealing glasses or anode materials for Li-batteries, has been analysed at the intermediate length scale by a combination of high field standard and advanced 1D/2D nuclear magnetic resonance techniques. The nature and extent of B/P mixing were analysed using the (11)B((31)P) dipolar heteronuclear multiple quantum coherence NMR sequence and the data interpretation allowed (i) detecting the presence and analysing the nature of the B-O-P linkages, (ii) re-interpreting the 1D (31)P spectra and (iii) extracting the proportion of P connected to borate species. Interaction between the different borate species was analysed using the (11)B double quantum-simple quantum experiment to (i) investigate the presence and nature of the B-O-B linkage, (ii) assign the different borate species observed all along the composition line and (iii) monitor the borate network formation. In addition, (119)Sn static NMR was used to investigate the evolution of the chemical environment of the tin polyhedra. Altogether, the set of data allowed determining the structural units constituting the glass network and quantifying the extent of B/P mixing. The structural data were then used to explain the non-linear and unusual evolution of the glass transition temperature.

7.
Chem Commun (Camb) ; 51(45): 9284-6, 2015 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-25891539

RESUMO

The long-standing debate about the presence of P-O-B(3) linkages in glasses has been solved by high-field scalar correlation NMR. Previously suggested by dipolar NMR methods, the presence of such species has been definitively demonstrated by (11)B((31)P) J-HMQC NMR techniques. The results indicate that borophosphate networks contain P-O-B(3) bonds and thus present a higher degree of atomic homogeneity than previously thought.

8.
Sci Rep ; 5: 8175, 2015 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-25640229

RESUMO

Reconstructing pH from biogenic carbonates using boron isotopic compositions relies on the assumption that only borate, and no boric acid, is present. Red coralline algae are frequently used in palaeoenvironmental reconstruction due to their widespread distribution and regular banding frequency. Prior to undertaking pH reconstructions using red coralline algae we tested the boron composition of the red coralline alga Lithothamnion glaciale using high field NMR. In bulk analysed samples, thirty percent of boron was present as boric acid. We suggest that prior to reconstructing pH using coralline algae 1) species-specific boron compositions and 2) within-skeleton special distributions of boron are determined for multiple species. This will enable site selective boron analyses to be conducted validating coralline algae as palaeo-pH proxies based on boron isotopic compositions.


Assuntos
Boro/química , Ressonância Magnética Nuclear Biomolecular , Rodófitas/química , Concentração de Íons de Hidrogênio , Rodófitas/metabolismo , Especificidade da Espécie
9.
Transpl Infect Dis ; 16(3): 421-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24797543

RESUMO

BACKGROUND: Levofloxacin is routinely used for the prevention of invasive bacterial infections during autologous peripheral blood stem cell transplantation (APBSCT). However, increasing rates of bacterial sepsis were noted at our institution among multiple myeloma (MM) patients undergoing outpatient APBSCT with melphalan-based chemotherapy and levofloxacin prophylaxis. We assessed the impact of a change in antibacterial prophylaxis from oral levofloxacin (Period 1) to sequential oral levofloxacin followed by ertapenem (Period 2). METHODS: Electronic medical records were reviewed to identify MM patients who underwent APBSCT in the outpatient clinic between October 2007 and April 2012. RESULTS: Over a 4.5-year period, 165 outpatient APBSCTs were eligible for the analysis. Fewer overall bacteremias occurred during Period 2 as compared with Period 1 (0.5 cases per 100 person-days vs. 2.4 cases per 100 person-days, P<0.001). In addition, fewer patients were hospitalized for neutropenic fever while receiving sequential prophylaxis (45.7% vs. 75.7% of outpatient APBSCT recipients during Periods 2 and 1, respectively; P<0.001). In Kaplan-Meier analysis, receipt of sequential prophylaxis (Period 2) was significantly associated with overall bacteremia-free survival within 30 days after the APBSCT (P<0.001). No significant differences were seen in the number of patients developing Clostridium difficile infection or ertapenem-resistant gram-negative bacteremia between study periods. CONCLUSION: In conclusion, sequential prophylaxis may effectively prevent episodes of bacteremia and hospitalizations in neutropenic MM outpatient APBSCT recipients. Prospective studies that involve larger numbers of MM patients with extended periods of follow-up are ultimately required to define the safety and efficacy of sequential antibacterial prophylaxis.


Assuntos
Antibacterianos/uso terapêutico , Bacteriemia/prevenção & controle , Levofloxacino/uso terapêutico , Mieloma Múltiplo/terapia , Transplante de Células-Tronco de Sangue Periférico/efeitos adversos , beta-Lactamas/uso terapêutico , Idoso , Antibacterianos/administração & dosagem , Antineoplásicos , Ertapenem , Feminino , Hospitalização , Humanos , Levofloxacino/administração & dosagem , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Estudos Retrospectivos , beta-Lactamas/administração & dosagem
11.
Blood Cancer J ; 3: e165, 2013 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-24292417

RESUMO

(18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) and computed tomography (CT) are useful imaging modalities for evaluating tumor progression and treatment responses in genetically engineered mouse models of solid human cancers, but the potential of integrated FDG-PET/CT for assessing tumor development and new interventions in transgenic mouse models of human blood cancers such as multiple myeloma (MM) has not been demonstrated. Here we use BALB/c mice that contain the newly developed iMyc(ΔEµ) gene insertion and the widely expressed H2-L(d)-IL6 transgene to demonstrate that FDG-PET/CT affords an excellent research tool for assessing interleukin-6- and MYC-driven plasma cell tumor (PCT) development in a serial, reproducible and stage- and lesion-specific manner. We also show that FDG-PET/CT permits determination of objective drug responses in PCT-bearing mice treated with the investigational proteasome inhibitor ixazomib (MLN2238), the biologically active form of ixazomib citrate (MLN9708), that is currently in phase 3 clinical trials in MM. Overall survival of 5 of 6 ixazomib-treated mice doubled compared with mice left untreated. One outlier mouse presented with primary refractory disease. Our findings demonstrate the utility of FDG-PET/CT for preclinical MM research and suggest that this method will play an important role in the design and testing of new approaches to treat myeloma.

12.
Bone Marrow Transplant ; 48(11): 1444-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23749109

RESUMO

Chemotherapy plus G-CSF (C+G) and G-CSF alone are two of the most common methods used to mobilize CD34(+) cells for autologous hematopoietic SCT (AHSCT). In order to compare and determine the real-world outcomes and costs of these strategies, we performed a retrospective study of 226 consecutive patients at 11 medical centers (64 lymphoma, 162 multiple myeloma), of whom 55% of lymphoma patients and 66% of myeloma patients received C+G. Patients with C+G yielded more CD34(+) cells/day than those with G-CSF alone (lymphoma: average 5.51 × 10(6) cells/kg on day 1 vs 2.92 × 10(6) cells/kg, P=0.0231; myeloma: 4.16 × 10(6) vs 3.69 × 10(6) cells/kg, P<0.00001) and required fewer days of apheresis (lymphoma: average 2.11 vs 2.96 days, P=0.012; myeloma: 2.02 vs 2.83 days, P=0.0015), although nearly all patients ultimately reached the goal of 2 × 10(6) cells/kg. With the exception of higher rates of febrile neutropenia in myeloma patients with C+G (17% vs 2%, P<0.05), toxicities and other outcomes were similar. Mobilization with C+G cost significantly more (lymphoma: median $10,300 vs $7300, P<0.0001; myeloma: $8800 vs $5600, P<0.0001), although re-mobilization adds $6700 for drugs alone. Our results suggest that although both C+G and G-CSF alone are effective mobilization strategies, C+G may be more cost-effective for patients at high risk of insufficient mobilization.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/economia , Fator Estimulador de Colônias de Granulócitos/economia , Mobilização de Células-Tronco Hematopoéticas/economia , Transplante de Células-Tronco Hematopoéticas/economia , Adulto , Idoso , Anticorpos Monoclonais Murinos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclofosfamida/administração & dosagem , Etoposídeo/administração & dosagem , Feminino , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Mobilização de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Rituximab , Transplante Autólogo/economia , Transplante Autólogo/métodos , Resultado do Tratamento , Adulto Jovem
13.
J Chem Phys ; 137(14): 144201, 2012 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-23061841

RESUMO

We have recently shown that the dipolar-mediated heteronuclear multiple-quantum coherence (D-HMQC) method allows observing through-space proximities between spin-1/2 ((1)H, (13)C, (31)P...) and quadrupolar ((23)Na, (27)Al...) nuclei. However, the D-HMQC effectiveness depends on the choice of the heteronuclear dipolar recoupling sequence. Here, we compare the efficiency and the robustness of four rotor-synchronized sequences: the symmetry-based ones, R4(1)(2)R4(1)(-2) and its super-cycled version, SR4(1)(2), and two schemes based on simultaneous amplitude and frequency modulations, denoted SFAM-1 and SFAM-2. For the SFAM methods, we point out efficient recoupling conditions that facilitate their experimental optimization and we introduce analytical expressions for the buildup of D-HMQC signal in the case of an isolated spin pair. We show that the main differences between these four sequences lie in the number of adjustable parameters and in their robustness with respect to chemical shift and homonuclear dipolar interactions. The relative performances of these four recoupling sequences are analyzed using average Hamiltonian theory, numerical simulations, and (27)Al-{(31)P} D-HMQC experiments on crystalline aluminophosphate.

14.
Phys Chem Chem Phys ; 13(37): 16786-94, 2011 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-21853181

RESUMO

We show in this article how the spatial proximity between phosphorus and quadrupolar nuclei can be efficiently and easily investigated with the D-HMQC (Dipolar Hetero-nuclear Multiple-Quantum Coherences) NMR technique. Compared to the commonly used CP-HETCOR (Cross-Polarisation HETero-nuclear CORrelation) sequence, the D-HMQC pulse scheme exhibits a higher sensitivity and a better robustness with respect to spinning frequency, electronic shielding and quadrupole interaction, and thus does not require time-consuming and complicated optimisation procedures. The advantages of the D-HMQC are demonstrated in this article through the acquisition of (31)P/S through-space two-dimensional correlation NMR spectra providing unreported structural information on (i) a sodium alumino-silicate glass doped with only 3% of P(2)O(5), (ii) a potassium boro-phosphate glass containing BO(3) and BO(4) groups and (iii) a crystalline zirconium vanado-phosphate. All these systems, representative of the most important mixed phosphate network materials, cannot be correctly investigated with the conventional CP-HETCOR NMR technique.

15.
Bone Marrow Transplant ; 45(1): 63-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19543330

RESUMO

This was an open-label, single-center, phase II study of 20 patients with multiple myeloma who were either proven poor mobilizers (n=10; group A) or predicted poor mobilizers (n=10; group B) and were planned for autologous hematopoietic SCT. The aim was to assess the safety and efficacy of plerixafor for stem cell mobilization and tumor cell contamination. The peripheral blood (PB) CD34+ cell count was generally very low pre- plerixafor and increased significantly post-plerixafor administration. Cumulative apheresis yields of > or =2 x 10(6) CD34+ cells/kg were observed in 7 of 10 patients (group A) and 8 of 10 patients (group B). Among the proven poor mobilizers, there was no evidence of tumor cell mobilization in the PB after G-CSF plus plerixafor treatment. Seventeen of 20 (85%) patients underwent transplantation. Neutrophil engraftment occurred at a median of 13 days for all patients. Platelet engraftment occurred at a median of 16 days and 19 days for all proven and predicted poor mobilizers, respectively. At 12 months, 12 of 17 patients had documented durable grafts, 3 of 17 patients died and 2 of 17 patients were lost to follow-up; but they had documented graft durability at the previous 3- and 6-month visit. The safety profile of plerixafor in all patients was consistent with previous reports.


Assuntos
Remoção de Componentes Sanguíneos/métodos , Mobilização de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco Hematopoéticas/métodos , Mieloma Múltiplo/terapia , Adolescente , Adulto , Idoso , Antígenos CD34/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Bone Marrow Transplant ; 41(4): 331-8, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17994119

RESUMO

AMD3100 given with G-CSF has been shown to mobilize CD34+ cells in non-Hodgkin's lymphoma (NHL), multiple myeloma (MM), and Hodgkin's disease (HD) patients who could not collect sufficient cells for autologous transplant following other mobilization regimens. These poor mobilizers are usually excluded from company-sponsored trials, but have been included in an AMD3100 Single Patient Use protocol, referred to as a Compassionate Use Protocol (CUP). A cohort of 115 data-audited poor mobilizers in CUP was assessed, with the objective being to collect > or =2 x 10(6) CD34+ cells per kg following AMD3100 plus G-CSF mobilization. The rates of successful CD34+ cell collection were similar for patients who previously failed chemotherapy mobilization or cytokine-only mobilization: NHL -- 60.3%, MM -- 71.4% and HD -- 76.5%. Following transplant, median times to neutrophil and PLT engraftment were 11 days and 18 days, respectively. Engraftment was durable. There were no drug-related serious adverse events. Of the adverse events considered related to AMD3100, two (1.6%) were severe (one patient -- headache, one patient -- nightmares). Other AMD3100-related adverse events were mild (84.8%) or moderate (13.6%). The most common AMD3100-related adverse events were gastrointestinal reactions, injection site reactions and paresthesias. AMD3100 plus G-CSF offers a new treatment to collect CD34+ cells for autologous transplant from poor mobilizers, with a high success rate.


Assuntos
Antígenos CD34 , Fatores Estimuladores de Colônias/uso terapêutico , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Mobilização de Células-Tronco Hematopoéticas/métodos , Compostos Heterocíclicos/uso terapêutico , Transtornos Linfoproliferativos/terapia , Terapia de Salvação/métodos , Adulto , Idoso , Benzilaminas , Ciclamos , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Sobrevivência de Enxerto , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Transplante Autólogo/métodos
18.
Magn Reson Chem ; 45 Suppl 1: S187-91, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18098351

RESUMO

We present the transferred echo double-resonance multiple-quantum MAS (TEDOR-MQMAS) method that allows to analyze under high resolution the through-bond connectivities between spin-1/2 and quadrupolar nuclei. This method avoids some of the limitations related to the spin-lock of half-integer quadrupolar nuclei under MAS. However, the losses observed during the TEDOR transfer are related to the T'(2) constants, and they may thus be more important than those observed during the CP-MAS transfer, which are related to T(1rho) > T'(2).

20.
Leukemia ; 20(9): 1467-73, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16855634

RESUMO

New uniform response criteria are required to adequately assess clinical outcomes in myeloma. The European Group for Blood and Bone Marrow Transplant/International Bone Marrow Transplant Registry criteria have been expanded, clarified and updated to provide a new comprehensive evaluation system. Categories for stringent complete response and very good partial response are added. The serum free light-chain assay is included to allow evaluation of patients with oligo-secretory disease. Inconsistencies in prior criteria are clarified making confirmation of response and disease progression easier to perform. Emphasis is placed upon time to event and duration of response as critical end points. The requirements necessary to use overall survival duration as the ultimate end point are discussed. It is anticipated that the International Response Criteria for multiple myeloma will be widely used in future clinical trials of myeloma.


Assuntos
Mieloma Múltiplo/patologia , Resultado do Tratamento , Humanos , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/terapia , Análise de Sobrevida
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