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1.
Int J Mol Sci ; 23(18)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36142637

RESUMO

Tau is a widespread neuroprotein that regulates the cytoskeleton assembly. In some neurological disorders, known as tauopathies, tau is dissociated from the microtubule and forms insoluble neurofibrillary tangles. Tau comprises four pseudorepeats (R1-R4), containing one (R1, R2, R4) or two (R3) histidines, that potentially act as metal binding sites. Moreover, Cys291 and Cys322 in R2 and R3, respectively, might have an important role in protein aggregation, through possible disulfide bond formation, and/or affecting the binding and reactivity of redox-active metal ions, as copper. We, therefore, compare the interaction of copper with octadeca-R3-peptide (R3C) and with the mutant containing an alanine residue (R3A) to assess the role of thiol group. Spectrophotometric titrations allow to calculate the formation constant of the copper(I) complexes, showing a remarkable stronger interaction in the case of R3C (log Kf = 13.4 and 10.5 for copper(I)-R3C and copper(I)-R3A, respectively). We also evaluate the oxidative reactivity associated to these copper complexes in the presence of dopamine and ascorbate. Both R3A and R3C peptides increase the capability of copper to oxidize catechols, but copper-R3C displays a peculiar mechanism due to the presence of cysteine. HPLC-MS analysis shows that cysteine can form disulfide bonds and dopamine-Cys covalent adducts, with potential implication in tau aggregation process.


Assuntos
Doença de Alzheimer , Proteínas tau , Alanina , Doença de Alzheimer/metabolismo , Cobre/metabolismo , Cisteína , Dissulfetos , Dopamina , Humanos , Peptídeos/química , Agregados Proteicos , Proteínas tau/metabolismo
2.
Cancer ; 127(18): 3413-3421, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34181755

RESUMO

BACKGROUND: Combined therapy with carfilzomib, bendamustine, and dexamethasone was evaluated in this multicenter phase 1/2 trial conducted within the European Myeloma Network (EMN09 trial). METHODS: Sixty-three patients with relapsed/refractory multiple myeloma who had received ≥2 lines of prior therapy were included. The phase 1 portion of the study determined the maximum tolerated dose of carfilzomib with bendamustine set at 70 mg/m2 on days 1 and 8. After 8 cycles, responding patients received maintenance therapy with carfilzomib and dexamethasone until progression. RESULTS: On the basis of the phase 1 results, the recommended phase 2 dose for carfilzomib was 27 mg/m2 twice weekly in weeks 1, 2, and 3. Fifty-two percent of patients achieved a partial response or better, and 32% reached a very good partial response or better. The clinical benefit rate was 93%. After a median follow-up of 21.9 months, the median progression-free survival was 11.6 months, and the median overall survival was 30.4 months. The reported grade ≥3 hematologic adverse events (AEs) were lymphopenia (29%), neutropenia (25%), and thrombocytopenia (22%). The main nonhematologic grade ≥3 AEs were pneumonia, thromboembolic events (10%), cardiac AEs (8%), and hypertension (2%). CONCLUSIONS: In heavily pretreated patients who have relapsed/refractory multiple myeloma, combined carfilzomib, bendamustine, and dexamethasone is an effective treatment option administered in the outpatient setting. Infection prophylaxis and attention to patients with cardiovascular predisposition are required.


Assuntos
Mieloma Múltiplo , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cloridrato de Bendamustina/efeitos adversos , Dexametasona , Humanos , Recidiva Local de Neoplasia/tratamento farmacológico , Oligopeptídeos
3.
Inorg Chem ; 59(1): 274-286, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31820933

RESUMO

Tau protein is present in significant amounts in neurons, where it contributes to the stabilization of microtubules. Insoluble neurofibrillary tangles of tau are associated with several neurological disorders known as tauopathies, among which is Alzheimer's disease. In neurons, tau binds tubulin through its microtubule binding domain which comprises four imperfect repeats (R1-R4). The histidine residues contained in these fragments are potential binding sites for metal ions and are located close to the regions that drive the formation of amyloid aggregates of tau. In this study, we present a detailed characterization through potentiometric and spectroscopic methods of the binding of copper in both oxidation states to R1 and R3 peptides, which contain one and two histidine residues, respectively. We also evaluate how the redox cycling of copper bound to tau peptides can mediate oxidation that can potentially target exogenous substrates such as neuronal catecholamines. The resulting quinone oxidation products undergo oligomerization and can competitively give post-translational peptide modifications yielding catechol adducts at amino acid residues. The presence of His-His tandem in the R3 peptide strongly influences both the binding of copper and the reactivity of the resulting copper complex. In particular, the presence of the two adjacent histidines makes the copper(I) binding to R3 much stronger than in R1. The copper-R3 complex is also much more active than the copper-R1 complex in promoting oxidative reactions, indicating that the two neighboring histidines activate copper as a catalyst in molecular oxygen activation reactions.


Assuntos
Complexos de Coordenação/química , Cobre/química , Fragmentos de Peptídeos/química , Proteínas tau/química , Sítios de Ligação , Humanos , Conformação Molecular
4.
Blood ; 127(9): 1102-8, 2016 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-26729895

RESUMO

Lenalidomide-dexamethasone improved outcome in newly diagnosed elderly multiple myeloma patients. We randomly assigned 662 patients who were age ≥65 years or transplantation-ineligible to receive induction with melphalan-prednisone-lenalidomide (MPR) or cyclophosphamide-prednisone-lenalidomide (CPR) or lenalidomide plus low-dose dexamethasone (Rd). The primary end point was progression-free survival (PFS) in triplet (MPR and CPR) vs doublet (Rd) lenalidomide-containing regimens. After a median follow-up of 39 months, the median PFS was 22 months for the triplet combinations and 21 months for the doublet (P = .284). The median overall survival (OS) was not reached in either arms, and the 4-year OS was 67% for the triplet and 58% for the doublet arms (P = .709). By considering the 3 treatment arms separately, no difference in outcome was detected among MPR, CPR, and Rd. The most common grade ≥3 toxicity was neutropenia: 64% in MPR, 29% in CPR, and 25% in Rd patients (P < .0001). Grade ≥3 nonhematologic toxicities were similar among arms and were mainly infections (6.5% to 11%), constitutional (3.5% to 9.5%), and cardiac (4.5% to 6%), with no difference among the arms. In conclusion, in the overall population, the alkylator-containing triplets MPR and CPR were not superior to the alkylator-free doublet Rd, which was associated with lower toxicity. This study was registered at www.clinicaltrials.gov as #NCT01093196.


Assuntos
Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/tratamento farmacológico , Talidomida/análogos & derivados , Idoso , Idoso de 80 Anos ou mais , Demografia , Intervalo Livre de Doença , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Lenalidomida , Masculino , Pessoa de Meia-Idade , Talidomida/efeitos adversos , Talidomida/uso terapêutico , Resultado do Tratamento
5.
Eur J Haematol ; 98(3): 289-295, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27893171

RESUMO

OBJECTIVE: There is no strong evidence to guide therapeutic approach to multiple myeloma (MM) patients who experience first relapse. The treatment choice can be difficult since currently all patients are exposed to novel agents as thalidomide, bortezomib and lenalidomide. METHODS: In this retrospective analysis, we evaluated the best therapeutic sequence, the role of retreatment, and the most beneficial cutoff of first remission in order to choose retreatment, analyzing 476 patients relapsed after first-line therapy. RESULTS: Bortezomib-based regimens upfront followed by lenalidomide-based regimens at first relapse resulted in significantly better second progression-free survival (2ndPFS), PFS2, and overall survival (OS) compared to the opposite sequence. Changing therapy resulted in significantly better 2ndPFS in the whole population, whereas PFS2 was significantly longer only in patients who underwent maintenance therapy. Moreover, until PFS1 was shorter than 27 months, changing therapy at first relapse significantly extended 2ndPFS and PFS2 compared to retreatment, whereas similar outcomes were observed between the two strategies, when PFS1 was longer than 27 months. CONCLUSION: Lacking randomized trials, our study could help to choose the most appropriate therapy algorithm in patients with MM.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Bortezomib/administração & dosagem , Terapia Combinada , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Lenalidomida , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/mortalidade , Estadiamento de Neoplasias , Estudos Retrospectivos , Terapia de Salvação , Análise de Sobrevida , Talidomida/administração & dosagem , Talidomida/análogos & derivados
6.
Magn Reson Med ; 73(5): 2015-24, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24894844

RESUMO

PURPOSE: In this MRI study, diffusional kurtosis imaging (DKI) and T2 * multiecho relaxometry were measured from the white matter (WM) of human brains and correlated with each other, with the aim of investigating the influence of magnetic-susceptibility (Δχ (H2O-TISSUE) ) on the contrast. METHODS: We focused our in vivo analysis on assessing the dependence of mean, axial, and radial kurtosis (MK, K‖ , K⊥ ), as well as DTI indices on Δχ (H2O-TISSUE) (quantified by T2 *) between extracellular water and WM tissue molecules. Moreover, Monte Carlo (MC) simulations were used to elucidate experimental data. RESULTS: A significant positive correlation was observed between K⊥ , MK and R2 * = 1/T2 *, suggesting that Δχ (H2O-TISSUE) could be a source of DKI contrast. In this view, K⊥ and MK-map contrasts in human WM would not just be due to different restricted diffusion processes of compartmentalized water but also to local Δχ (H2O-TISSUE) . However, MC simulations show a strong dependence on microstructure rearrangement and a feeble dependence on Δχ (H2O-TISSUE) of DKI signal. CONCLUSION: Our results suggests a concomitant and complementary existence of multi-compartmentalized diffusion process and Δχ (H2O-TISSUE) in DKI contrast that might explain why kurtosis contrast is more sensitive than DTI in discriminating between different tissues. However, more realistic numerical simulations are needed to confirm this statement.


Assuntos
Encéfalo/anatomia & histologia , Encéfalo/metabolismo , Imagem de Difusão por Ressonância Magnética/métodos , Imagem Ecoplanar/métodos , Líquido Extracelular/fisiologia , Substância Branca/anatomia & histologia , Substância Branca/metabolismo , Adulto , Corpo Caloso/anatomia & histologia , Corpo Caloso/metabolismo , Feminino , Humanos , Magnetismo , Masculino , Modelos Teóricos , Método de Monte Carlo , Distribuição Normal , Análise Numérica Assistida por Computador , Valores de Referência , Estatística como Assunto
7.
Plant Physiol Biochem ; 206: 108187, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38100889

RESUMO

The use of PGPR is widely accepted as a promising tool for a more sustainable agricultural production and improved plant abiotic stress resistance. This study tested the ability of PVr_9, a novel bacterial strain, homologous to Beijerinckia fluminensis, to increase salt stress tolerance in A. thaliana. In vitro plantlets inoculated with PVr_9 and treated with 150 mM NaCl showed a reduction in primary root growth inhibition compared to uninoculated ones, and a leaf area significantly less affected by salt. Furthermore, salt-stressed PVr_9-inoculated plants had low ROS and 8-oxo-dG, osmolytes, and ABA content along with a modulation in antioxidant enzymatic activities. A significant decrease in Na+ in the leaves and a corresponding increase in the roots were also observed in salt-stressed inoculated plants. SOS1, NHX1 genes involved in plant salt tolerance, were up-regulated in PVr_9-inoculated plants, while different MYB genes involved in salt stress signal response were down-regulated in both roots and shoots. Thus, PVr_9 was able to increase salt tolerance in A. thaliana, thereby suggesting a role in ion homeostasis by reducing salt stress rather than inhibiting total Na+ uptake. These results showed a possible molecular mechanism of crosstalk between PVr_9 and plant roots to enhance salt tolerance, and highlighted this bacterium as a promising PGPR for field applications on agronomical crops.


Assuntos
Arabidopsis , Beijerinckiaceae , Arabidopsis/metabolismo , Tolerância ao Sal/genética , Proteínas de Plantas/genética , Beijerinckiaceae/metabolismo , Agrobacterium tumefaciens , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/genética
8.
EJNMMI Radiopharm Chem ; 9(1): 38, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38705946

RESUMO

BACKGROUND: Positron emission tomography (PET) is a highly sensitive method that provides fine resolution images, useful in the field of clinical diagnostics. In this context, Zirconium-89 (89Zr)-based imaging agents have represented a great challenge in molecular imaging with immuno-PET, which employs antibodies (mAbs) as biological vectors. Indeed, immuno-PET requires radionuclides that can be attached to the mAb to provide stable in vivo conjugates, and for this purpose, the radioactive element should have a decay half-life compatible with the time needed for the biodistribution of the immunoglobulin. In this regard, 89Zr is an ideal radioisotope for immuno-PET because its half-life perfectly matches the in vivo pharmacokinetics of mAbs. RESULTS: The main objective of this work was the design and synthesis of a series of bifunctional octadentate pseudopeptides able to generate stable 89Zr complexes. To achieve this, here we investigated hydroxamate, N-methylhydroxamate and catecholate chelating moieties in complexing radioactive zirconium. N-methylhydroxamate proved to be the most effective 89Zr-chelating group. Furthermore, the increased flexibility and hydrophilicity obtained by using polyoxyethylene groups spacing the hydroxamate units led to chelators capable of rapidly forming (15 min) stable and water-soluble complexes with 89Zr under mild reaction conditions (aqueous environment, room temperature, and physiological pH) that are mandatory for complexation reactions involving biomolecules. Additionally, we report challenge experiments with the competitor ligand EDTA and metal ions such as Fe3+, Zn2+ and Cu2+. In all examined conditions, the chelators demonstrated stability against transmetallation. Finally, a maleimide moiety was introduced to apply one of the most promising ligands in bioconjugation reactions through Thiol-Michael chemistry. CONCLUSION: Combining solid phase and solution synthesis techniques, we identified novel 89Zr-chelating molecules with a peptide scaffold. The adopted chemical design allowed modulation of molecular flexibility, hydrophilicity, as well as the decoration with different zirconium chelating groups. Best results in terms of 89Zr-chelating properties were achieved with the N-methyl hydroxamate moiety. The Zirconium complexes obtained with the most effective compounds were water-soluble, stable to transmetallation, and resistant to peptidases for at least 6 days. Further studies are needed to assess the potential of this novel class of molecules as Zirconium-chelating agents for in vivo applications.

9.
Blood ; 116(23): 4745-53, 2010 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-20807892

RESUMO

In a recent phase 3 trial, bortezomib-melphalan-prednisone-thalidomide followed by maintenance treatment with bortezomib-thalidomide demonstrated superior efficacy compared with bortezomib-melphalan-prednisone. To decrease neurologic toxicities, the protocol was amended and patients in both arms received once-weekly instead of the initial twice-weekly bortezomib infusions: 372 patients received once-weekly and 139 twice-weekly bortezomib. In this post-hoc analysis we assessed the impact of the schedule change on clinical outcomes and safety. Long-term outcomes appeared similar: 3-year progression-free survival rate was 50% in the once-weekly and 47% in the twice-weekly group (P > .999), and 3-year overall survival rate was 88% and 89%, respectively (P = .54). The complete response rate was 30% in the once-weekly and 35% in the twice-weekly group (P = .27). Nonhematologic grade 3/4 adverse events were reported in 35% of once-weekly patients and 51% of twice-weekly patients (P = .003). The incidence of grade 3/4 peripheral neuropathy was 8% in the once-weekly and 28% in the twice-weekly group (P < .001); 5% of patients in the once-weekly and 15% in the twice-weekly group discontinued therapy because of peripheral neuropathy (P < .001). This improvement in safety did not appear to affect efficacy. This study is registered at http://www.clinicaltrials.gov as NCT01063179.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ácidos Borônicos/administração & dosagem , Mieloma Múltiplo/tratamento farmacológico , Pirazinas/administração & dosagem , Idoso , Ácidos Borônicos/efeitos adversos , Bortezomib , Intervalo Livre de Doença , Esquema de Medicação , Feminino , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Melfalan/administração & dosagem , Melfalan/efeitos adversos , Pessoa de Meia-Idade , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/patologia , Estadiamento de Neoplasias , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/epidemiologia , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Pirazinas/efeitos adversos , Talidomida/administração & dosagem , Talidomida/efeitos adversos , Resultado do Tratamento
10.
Ann Hematol ; 90(12): 1449-56, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21437586

RESUMO

In newly diagnosed multiple myeloma (MM), three/four-drug combinations as induction therapy seem to be more effective compared with two-drug associations in terms of response rate and duration of remission. Moreover, there is an emergent body of evidences that consolidation/maintenance therapy improves the quality of response and remission duration. However, the impact of these strategies in relapsed/refractory MM (r-rMM) is still unknown. This phase II study explored the four-drug combination of thalidomide, dexamethasone, pegylated liposomal doxorubicin (pLD), and bortezomib (ThaDD-V) as induction followed by consolidation therapy based on bortezomib-dexamethasone and thalidomide-dexamethasone and maintenance therapy with thalidomide in r-rMM patients. The primary end points of this study were best response and toxicity of the planned therapy. Forty-six patients were enrolled. At the end of therapy, the best response was as follows: 37% complete response (CR), 34.5% VGPR, and 4.5% PR with an ORR of 76%. Patients receiving ≤ 2 prior regimens had a CR rate significantly higher than those heavily treated (41% vs 0%; p=0.010). With a median follow-up of 31 months, median time to progression (TTP) and OS were 18.5 months and 40 months, respectively. By a 6-month landmark analysis, patients who completed the protocol had a significantly longer TTP compared with those who did not because of toxicity (not reached vs 7 months; p<0.0001). After the dose intensity of bortezomib was reduced due to an excess of peripheral neuropathy (PN), grade 3 PN occurred in 7.5% of patients. ThaDD-V followed by consolidation-maintenance therapy seems to be very effective in patients with r-rMM provided that this procedure is used early on relapse when very deep responses seem to be the rule.


Assuntos
Antineoplásicos/uso terapêutico , Ácidos Borônicos/uso terapêutico , Dexametasona/uso terapêutico , Doxorrubicina/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/prevenção & controle , Pirazinas/uso terapêutico , Talidomida/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bortezomib , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/fisiopatologia , Recidiva , Indução de Remissão , Resultado do Tratamento
11.
J Hazard Mater ; 410: 124585, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33288336

RESUMO

Polyamidoamines are low cost and easily synthesized materials that may find applications in cations sequestration and water treatment. In this paper a new amido-aminoacid ligand containing methionine has been designed as a monomeric model of the corresponding polyamidoamine. The amido-aminoacid ligand has been synthesized in high yield, by reacting acrylamide and methionine via aza-Michael addition in water and mild temperature conditions. The reaction has been monitored by NMR and Raman spectroscopies and the crystal structure has been determined by X-ray diffraction analysis. The coordination ability of the ligand towards Cu2+ cations in water, as well as its affinity for Ni2+ and Co2+ has been studied by potentiometric and spectrophotometric techniques. The divalent metal cations sequestration from water may occur with sequential selection by changing the pH of the solution. The copper complex with two coordinated ligands has been fully characterized in the solid state by single crystal X-ray diffraction. The results are discussed with a view to use these materials in the treatment of water contaminated by toxic transition metal ions.

12.
Eur J Haematol ; 84(6): 474-83, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20331733

RESUMO

OBJECTIVES: With the aim to address the issue whether high-dose therapy (HDT) is required after new drugs combinations to improve outcome of elderly newly diagnosed multiple myeloma (MM) patients, we compared the toxicity and the outcome of ThaDD plus maintenance to those of ThaDD plus HDT-autologous stem cell transplantation (ASCT). METHODS: Sixty-two patients not eligible for HDT receiving six courses of ThaDD regimen plus maintenance with thalidomide were compared to 26 patients eligible for HDT treated with four courses of ThaDD followed by melphalan 100-200 mg/m(2) and ASCT. The two groups were matched for the main characteristics except for age favouring the HDT group. RESULTS AND CONCLUSIONS: Complete remission (CR) obtained with ThaDD plus maintenance was 24% whereas it was 57% after ThaDD plus HDT-ASCT (P = 0.0232). However, after a median follow-up of 36 months, median time to progression (TTP) and progression free survival (PFS) of the group of patients undergone HDT were not significantly different to those of patients receiving ThaDD plus maintenance (32 vs. 31 months: P = 0.962; 32 vs. 29 months: P = 0.726, respectively). Five-year overall survival (OS) was 49% in the first group and 46% in the latter one (P = 0.404). As expected, a significantly higher incidence of grade 3-4 neutropenia, thrombocytopenia, infections, mucositis and alopecia were observed in the ThaDD plus HDT group. Our results suggest that in elderly MM patients ThaDD plus HDT, albeit significantly increases CR rate, seems to be equivalent to ThaDD plus maintenance in terms of TTP, PFS and OS. These results challenge the requirement for HDT consolidation in this subset of patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/terapia , Transplante de Células-Tronco , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Terapia Combinada , Dexametasona/administração & dosagem , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Feminino , Humanos , Masculino , Melfalan/administração & dosagem , Polietilenoglicóis/administração & dosagem , Estudos Prospectivos , Análise de Sobrevida , Talidomida/administração & dosagem , Transplante Autólogo , Resultado do Tratamento
13.
J Inorg Biochem ; 205: 110980, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31931375

RESUMO

The two branched peptides (AAHAWG)4-PWT2 and (HAWG)4-PWT2 where synthesized by mounting linear peptides on a cyclam-based scaffold (PWT2), provided with four maleimide chains, through a thio-Michael reaction. The purpose of this study was primarily to verify if the two branched ligands had a Cu(II) coordination behavior reproducing that of the single-chain peptides, namely AAHAWG-NH2, which bears an Amino Terminal Cu(II)- and Ni(II)-Binding (ATCUN) Motif, and HAWG-NH2, which presents a His residue as the N-terminal amino acid, in a wide pH range. The study of Cu(II) binding was performed by potentiometric, spectroscopic (UV-vis absorption, CD, fluorescence) and ESI-MS techniques. ATCUN-type ligands ((AAHAWG)4-PWT2 and AAHAWG-NH2) were confirmed to bind one Cu(II) per peptide fragment at both pH 7.4 and pH 9.0, with a [NH2, 2N-, NIm] coordination mode. On the other hand, the ligand HAWG-NH2 forms a [CuL2]2+ species at neutral pH, while, at pH 9, the formation of 1:2 Cu(II):ligand adducts is prevented by amidic nitrogen deprotonation and coordination, to give rise solely to 1:1 species. Conversely, Cu(II) binding to (HAWG)4-PWT2 resulted in the formation of 1:2 copper:peptide chain also at pH 9: hence, through the latter branched peptide we obtained, at alkaline pH, the stabilization of a specific Cu(II) coordination mode which results unachievable using the corresponding single-chain peptide. This behavior could be explained in terms of high local peptide concentration on the basis of the speciation of the Cu(II)/single-chain peptide systems.


Assuntos
Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Cobre/química , Peptídeos/química , Peptídeos/síntese química
14.
Br J Haematol ; 144(5): 653-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19036082

RESUMO

Maintenance therapy was explored in multiple myeloma (MM) patients after conventional thalidomide, dexamethasone and pegylated liposomal doxorubicin (ThaDD). Patients with newly or relapsed MM obtaining at least minor response after 6 ThaDD courses, were randomised to receive alpha-interferon (IFN) 3 MU 3 times a week or thalidomide 100 mg daily until relapse. Both groups also received pulsed dexamethasone 20 mg 4 d a month. Fifty-one patients were randomized in the IFN-dexamethasone (ID) arm and 52 in the thalidomide-dexamethasone (TD) arm. The characteristics of two groups were similar. A significantly better 2-years progression-free survival (PFS; 63% vs. 32%; P = 0.024) and overall survival (84% vs. 68%; P = 0.030) was observed in the thalidomide arm. In high-risk patients and in those achieving less than very good partial response after induction, TD fared better in term of PFS. Main side effects were peripheral neuropathy and constipation in TD group, fatigue, anorexia and haematological toxicity in ID arm. There was a 21% probability of discontinuation at 3 years in the thalidomide arm and 44% in the IFN arm (P = 0.014). Low-dose thalidomide plus pulsed low-dose dexamethasone after conventional thalidomide combination-based therapy was also feasible in the long term, enabling significantly better residual disease control if compared with a standard maintenance therapy.


Assuntos
Dexametasona/administração & dosagem , Imunossupressores/uso terapêutico , Interferon-alfa/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Talidomida/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Dexametasona/uso terapêutico , Intervalo Livre de Doença , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/mortalidade , Estudos Prospectivos , Recidiva , Indução de Remissão , Estatísticas não Paramétricas , Taxa de Sobrevida , Talidomida/uso terapêutico
15.
Materials (Basel) ; 12(11)2019 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-31159493

RESUMO

A new technology was tested to improve the cooking efficiency of the raw mixture for Portland clinker production by the use of nano-Ca(OH)2. A decrease in the free lime concentration after the firing of approximately 35% and 55% in the nano-added clinkers burned at 1350 °C and 1450 °C, respectively, with respect to the standard Portland clinkers was observed. Moreover, in the nano-added clinkers, a slight decrease in alite (C3S), of approximately 2-4 wt%, and increase in belite (C2S), of approximately 5-6 wt%, were observed. Despite these variations, the C2S and C3S abundance lies within the ranges for standard Portland clinkers. The results showed that the nano-addition leads to an increase of the raw mixtures' cooking efficiency. The relatively low energy required for the clinker firing could be used to increase the plant productivity and decrease the CO2 emissions during clinker burning. The decrease of the work index of the clinkers produced by the use of the nano-Ca(OH)2 also contributes to the energy saving during clinker grinding. Differences were also found in the pore size distribution among nano-added clinkers and the standard Portland clinker. The smallest porosities with the modal volume lying in the class of 3∙10-6 mm3 were found to increase by the use of nano-Ca(OH)2. However, the pore volumes higher than 2.0∙10-5 mm3 decreased in the nano-added clinkers.

17.
Expert Opin Pharmacother ; 19(2): 137-149, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29265901

RESUMO

INTRODUCTION: Multiple Myeloma (MM) is a complex and heterogeneous plasma cell disorder. Sub-clones present before therapy and clonal evolution during therapy make this disease more resistant and finally refractory. These findings make us aware of the difficulty to target MM with few agents. Multi-drugs therapies allow us to target more pathways and more sub-clones both at diagnosis and in advanced disease. AREAS COVERED: In this review, the authors focus on the effectiveness and tolerability of three drug regimens (triplet) in comparison with two drug regimens (doublet) and discuss their implications in the present and future of MM therapy. EXPERT OPINION: It has been demonstrated that triplet regimens are better than doublet in terms of response rate and PFS in newly diagnosed, relapsed-refractory MM and in most patient subgroups. Whether this translates into OS improvement needs further demonstration. However, achievement of MRD negativity in most newly diagnosed and, firstly, in a consistent proportion of relapsed-refractory MM patients is very encouraging in this respect. However, not all patients are able to tolerate all triplet combinations; therefore, the choice should be based on patient characteristics, besides disease features. Finally, cost of triplets may be an important limitation in some countries.


Assuntos
Antineoplásicos/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Anticorpos Monoclonais/uso terapêutico , Compostos de Boro/uso terapêutico , Glicina/análogos & derivados , Glicina/uso terapêutico , Inibidores de Histona Desacetilases/uso terapêutico , Humanos , Mieloma Múltiplo/patologia , Mieloma Múltiplo/terapia , Oligopeptídeos/uso terapêutico , Transplante de Células-Tronco , Talidomida/uso terapêutico
19.
Curr Cancer Drug Targets ; 17(9): 769-781, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27659429

RESUMO

High-dose therapy (HDT) followed by autologous stem cell transplantation (ASCT) remains the standard of care for patients younger than 65 years of age with multiple myeloma (MM). However, this therapeutic approach has undergone substantial advances in this last decade, mainly due to the introduction of new drugs such as thalidomide, lenalidomide and bortezomib. These new drugs, in different combinations, have shown to significantly increase response rates after induction therapy and ASCT. Moreover, the positive results obtained with these agents in consolidation and maintenance strategies after ASCT strongly support the concept of continuous therapy, whose ultimate goal is the long-term control of the disease and the improvement of outcome. Preliminary data from studies investigating next generation proteasome inhibitors, such as carfilzomib and ixazomib, used upfront as well as at subsequent therapeutic lines, demonstrate the possibility of achieving molecular remission in most of the patients. The deeper responses obtained with new drugcombinations questioned the role of ASCT, and large, ongoing, phase 3 trials will shed light on the role and the timing of ASCT.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Mieloma Múltiplo/terapia , Transplante de Células-Tronco/métodos , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Autoenxertos , Bortezomib/uso terapêutico , Ensaios Clínicos como Assunto , Quimioterapia de Consolidação/métodos , Humanos , Lenalidomida , Mieloma Múltiplo/tratamento farmacológico , Talidomida/análogos & derivados , Talidomida/uso terapêutico , Transplante Autólogo/métodos
20.
Clin Lymphoma Myeloma Leuk ; 17S: S80-S87, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28760306

RESUMO

The prognosis of patients with multiple myeloma has significantly improved after the introduction of novel concepts of immunomodulation and proteasome inhibition in myeloma therapies. In conjunction with the use of high-dose therapy and autologous stem cell transplantation, these newer antimyeloma agents facilitated the augmentation of deeper responses and as a result, enhanced survival outcomes. Despite mounting clinical evidence that novel therapies may mitigate the poor prognostic impact of some predictors historically considered "harbingers of doom" in myeloma such as t(4;14), the benefit of these advances is less evident in patients who present with genetically defined high-risk features such as presence of chromosomal abnormalities del17p, t(14;16), or t(14;20), or among patients presenting with plasma cell leukemia. With better understanding of the biology of the disease and further recognition of the genomic instability of the high-risk clonal plasma cell influencing both inherent and acquired therapeutic resistance, newer targeted treatment strategies will hopefully improve prognosis in future among this subset of patients with poorer outcomes. In this review, we not only focus on how to identify the genetically defined high-risk patients with myeloma but also describe the most optimal antimyeloma combination strategies that so far have shown to demonstrate long-term benefits for these patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/métodos , Mieloma Múltiplo/terapia , Aberrações Cromossômicas , Terapia Combinada , Intervalo Livre de Doença , Perfilação da Expressão Gênica , Humanos , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Fatores de Risco , Transplante Autólogo
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