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1.
Brain ; 147(8): 2791-2802, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38643018

RESUMO

Neuropsychological impairments are common in children with drug-resistant epilepsy. It has been proposed that epilepsy surgery might alleviate these impairments by providing seizure freedom; however, findings from prior studies have been inconsistent. We mapped long-term neuropsychological trajectories in children before and after undergoing epilepsy surgery, to measure the impact of disease course and surgery on functioning. We performed a retrospective cohort study of 882 children who had undergone epilepsy surgery at Great Ormond Street Hospital (1990-2018). We extracted patient information and neuropsychological functioning [obtained from IQ tests (domains: full-scale IQ, verbal IQ, performance IQ, working memory and processing speed) and tests of academic attainment (reading, spelling and numeracy)] and investigated changes in functioning using regression analyses. We identified 500 children (248 females) who had undergone epilepsy surgery [median age at surgery = 11.9 years, interquartile range = (7.8, 15.0)] and neuropsychological assessment. These children showed declines in all domains of neuropsychological functioning in the time leading up to surgery (all P-values ≤0.001; e.g. ßFSIQ = -1.9, SEFSIQ = 0.3, PFSIQ < 0.001). Children lost on average one to four points per year, depending on the domain considered; 27%-43% declined by ≥10 points from their first to their last preoperative assessment. At the time of presurgical evaluation, most children (46%-60%) scored one or more standard deviations below the mean (<85) on the different neuropsychological domains; 37% of these met the threshold for intellectual disability (full-scale IQ < 70). On a group level, there was no change in performance from pre- to postoperative assessment on any of the domains (all P-values ≥0.128). However, children who became seizure free through surgery showed higher postoperative neuropsychological performance (e.g. rrb-FSIQ = 0.37, P < 0.001). These children continued to demonstrate improvements in neuropsychological functioning over the course of their long-term follow-up (e.g. ßFSIQ = 0.9, SEFSIQ = 0.3, PFSIQ = 0.004). Children who had discontinued antiseizure medication treatment at 1-year follow-up showed an 8- to 13-point advantage in postoperative working memory, processing speed and numeracy, and greater improvements in verbal IQ, working memory, reading and spelling (all P-values ≤0.034) over the postoperative period compared with children who were seizure free and still receiving antiseizure medication. In conclusion, by providing seizure freedom and the opportunity for antiseizure medication cessation, epilepsy surgery might not only halt but reverse the downward trajectory that children with drug-resistant epilepsy display in neuropsychological functioning. To halt this decline as soon as possible or, potentially, to prevent it from occurring in the first place, children with focal epilepsy should be considered for epilepsy surgery as early as possible after diagnosis.


Assuntos
Epilepsia Resistente a Medicamentos , Testes Neuropsicológicos , Humanos , Feminino , Criança , Masculino , Adolescente , Estudos Retrospectivos , Epilepsia Resistente a Medicamentos/cirurgia , Epilepsia Resistente a Medicamentos/psicologia , Epilepsia/cirurgia , Epilepsia/psicologia , Estudos de Coortes , Testes de Inteligência , Procedimentos Neurocirúrgicos
2.
J Biol Inorg Chem ; 29(1): 33-49, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38099935

RESUMO

Tetrahedral copper(II) and zinc(II) coordination compounds from 5-nitroimidazole derivatives, viz. 1-(2-chloroethyl)-2-methyl-5-nitroimidazole (cenz) and ornidazole 1-(3-chloro-2-hydroxypropyl)-2-methyl-5-nitroimidazole (onz), were synthesized and spectroscopically characterized. Their molecular structures were determined by X-ray diffraction studies. The complexes [Cu(onz)2X2], [Zn(onz)2X2], [Cu(cenz)2X2] and [Zn(cenz)2X2] (X- = Cl, Br), are stable in solution and exhibit positive LogD7.4 values that are in the range for molecules capable of crossing the cell membrane via passive difussion. Their biological activity against Toxoplasma gondi was investigated, and IC50 and lethal dose (LD50) values were determined. The ornidazole copper(II) compounds showed very good antiparasitic activity in its tachyzoite morphology. The interaction of the coordination compounds with DNA was examined by circular dichroism, fluorescence (using intercalating ethidium bromide and minor groove binding Hoechst 33258) and UV-Vis spectroscopy. The copper(II) compounds interact with the minor groove of the biomolecule, whereas weaker electrostatic interactions take place with the zinc(II) compounds. The spectroscopic data achieved for the two series of complexes (namely with copper(II) and zinc(II) as metal center) agree with the respective DNA-damage features observed by gel electrophoresis.


Assuntos
Complexos de Coordenação , Nitroimidazóis , Ornidazol , Toxoplasma , Cobre/química , Complexos de Coordenação/química , Toxoplasma/metabolismo , Zinco/química , DNA/química , Ligantes , Cristalografia por Raios X
3.
Ann Hematol ; 103(1): 321-334, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37971549

RESUMO

The current study includes all consecutive patients (N = 484) who received a reduced-intensity conditioning regimen (RIC) allogeneic hematopoietic stem cell transplantation in our center from 1999 to 2020. Conditioning regimens were based on fludarabine with melphalan or busulfan, with low-dose thiotepa and pharmacological GVHD prophylaxis consisted of cyclosporine A (CsA)-methotrexate (MTX)/mofetil (MMF) (n = 271), tacrolimus-sirolimus (n = 145), and post-transplantation cyclophosphamide (PTCy)-tacrolimus (n = 68). The median time of overall follow-up in survivors was 8 years (1-22 years) and was at least 3 years in all three GVHD prophylaxis groups. Thirty-three percent had a high or very high disease risk index, 56% ≥ 4 European bone marrow transplantation risk, and 65% ≥ 3 hematopoietic stem cell transplantation comorbidity index score-age score. Neutrophil and platelet engraftment was longer for PTCy-tacro (p 0.0001). Cumulative incidence of grade III-IV aGVHD was 17% at 200 days, and that of moderate-severe cGvHD was 36% at 8 years. GVHD prophylaxis was the only prognostic factor in the multivariable analyses for the development of aGVHD and moderate-severe cGVHD (p 0.0001). NRM and relapse incidences were 29% and 30% at 8 years, while OS and PFS rates were 43% and 39% at 8 years. At 3 years, OS was highest in the PTCy-tacro group (68%) than in the tacro-siro (61%) and CsA-MTX/MMF (49%) cohorts (p < 0.01). In the three groups, respectively, the 200-day incidence of grade III-IV aGvHD (6% vs. 12% vs. 23%) and 3-year moderate-severe cGVHD (8% vs. 40% vs. 38%) were lower in the PTCy cohort. These better outcomes were confirmed in multivariable analyses. Based on our recent results, the PTCy could be considered as a real GvHD prophylaxis in the RIC setting due to improve best 3-year GvHD and survival outcomes.


Assuntos
Doença Enxerto-Hospedeiro , Doenças Hematológicas , Transplante de Células-Tronco Hematopoéticas , Humanos , Ciclofosfamida/uso terapêutico , Ciclosporina/uso terapêutico , Doença Enxerto-Hospedeiro/epidemiologia , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/prevenção & controle , Doenças Hematológicas/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas/métodos , Metotrexato/uso terapêutico , Tacrolimo/uso terapêutico , Condicionamento Pré-Transplante/métodos
4.
Eur J Haematol ; 2024 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-39155459

RESUMO

OBJECTIVE: This retrospective single center study aims to describe changes in the severity and organ-specific distribution of GvHD, by comparing the outcomes of 3 distinct GvHD prophylaxis approaches. METHODS: Between January 2012 and June 2022, 226 patients underwent allogeneic hematopoietic stem cell transplantation from HLA-matched or 1-allele mismatched related or unrelated donors. Fifty-eight (26%) received prophylaxis with calcineurin inhibitor in combination with mycophenolate mofetil or a short course of methotrexate (Cohort-1), 87 (38%) tacrolimus plus sirolimus (Cohort-2), and 81 (36%) post-transplant cyclophosphamide (PTCy) plus tacrolimus (Cohort-3). RESULTS: The incidence of grade II-IV aGvHD was 69% vs. 41.4% vs. 27.2%; p < .01. The most significant reduction with PTCy was observed in both stage 3-4 skin and lower gastrointestinal (GI) involvement (p < .01). The incidence of moderate-to-severe cGvHD at 12 months was 34.5% vs. 34.5% vs. 6.2%; p < .01. Moderate-to-severe skin and GI cGvHD was less common after PTCy (p < .01). The 1-year GvHD-free/relapse-free survival was higher with PTCy (p < .01). CONCLUSIONS: Our study indicates that PTCy-based GvHD prophylaxis reduces the frequency and severity of both acute and chronic GvHD, with a notable decrease in severe GI and cutaneous manifestations. The higher GRFS may result in lower GvHD-related mortality, leading to an improved quality of life among survivors.

5.
Angew Chem Int Ed Engl ; 63(8): e202314773, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38055325

RESUMO

Molecular Dynamics (MD) simulations constitute a powerful tool that provides a 3D perspective of the dynamical behavior of chemical systems. Herein the first MD study of the dynamics of a catalytic organometallic system, in micellar media, is presented. The challenging methane catalytic functionalization into ethyl propionate through a silver-catalyzed process has been targeted as the case study. The intimate nature of the micelles formed with the surfactants sodium dodecylsulfate (SDS) and potassium perfluorooctane sulfonate (PFOS) has been ascertained, as well as the relative distribution of the main actors in this transformation, namely methane, the diazo reagent and the silver catalyst, the latter in two different forms: the initial compound and a silver-carbene intermediate. Catalyst deactivation occurs with halide containing surfactants dodecyltrimethylammonium chloride (DTAC) and Triton X-100. Computed simulations allow explaining the experimental results, indicating that micelles behave differently regarding the degree of accumulation and the local distribution of the reactants and their effect in the molecular collisions leading to net reaction.

6.
Lancet ; 399(10338): 1876-1885, 2022 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-35525255

RESUMO

BACKGROUND: Mediterranean and low-fat diets are effective in the primary prevention of cardiovascular disease. We did a long-term randomised trial to compare the effects of these two diets in secondary prevention of cardiovascular disease. METHODS: The CORDIOPREV study was a single-centre, randomised clinical trial done at the Reina Sofia University Hospital in Córdoba, Spain. Patients with established coronary heart disease (aged 20-75 years) were randomly assigned in a 1:1 ratio by the Andalusian School of Public Health to receive a Mediterranean diet or a low-fat diet intervention, with a follow-up of 7 years. Clinical investigators (physicians, investigators, and clinical endpoint committee members) were masked to treatment assignment; participants were not. A team of dietitians did the dietary interventions. The primary outcome (assessed by intention to treat) was a composite of major cardiovascular events, including myocardial infarction, revascularisation, ischaemic stroke, peripheral artery disease, and cardiovascular death. This study is registered with ClinicalTrials.gov, NCT00924937. FINDINGS: From Oct 1, 2009, to Feb 28, 2012, a total of 1002 patients were enrolled, 500 (49·9%) in the low-fat diet group and 502 (50·1%) in the Mediterranean diet group. The mean age was 59·5 years (SD 8·7) and 827 (82·5%) of 1002 patients were men. The primary endpoint occurred in 198 participants: 87 in the Mediterranean diet group and 111 in the low-fat group (crude rate per 1000 person-years: 28·1 [95% CI 27·9-28·3] in the Mediterranean diet group vs 37·7 [37·5-37·9] in the low-fat group, log-rank p=0·039). Multivariable-adjusted hazard ratios (HRs) of the different models ranged from 0·719 (95% CI 0·541-0·957) to 0·753 (0·568-0·998) in favour of the Mediterranean diet. These effects were more evident in men, with primary endpoints occurring in 67 (16·2%) of 414 men in the Mediterranean diet group versus 94 (22·8%) of 413 men in the low-fat diet group (multiadjusted HR 0·669 [95% CI 0·489-0·915], log-rank p=0·013), than in 175 women for whom no difference was found between groups. INTERPRETATION: In secondary prevention, the Mediterranean diet was superior to the low-fat diet in preventing major cardiovascular events. Our results are relevant to clinical practice, supporting the use of the Mediterranean diet in secondary prevention. FUNDING: Fundacion Patrimonio Comunal Olivarero; Fundacion Centro para la Excelencia en Investigacion sobre Aceite de Oliva y Salud; local, regional, and national Spanish Governments; European Union.


Assuntos
Isquemia Encefálica , Doenças Cardiovasculares , Dieta Mediterrânea , Acidente Vascular Cerebral , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Dieta com Restrição de Gorduras , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevenção Secundária/métodos
7.
J Biol Inorg Chem ; 28(4): 403-420, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37059909

RESUMO

Two ruthenium(II) polypyridyl complexes were prepared with the {Ru(phen)2}2+ moiety and a third sterically non-hindering bidentate ligand, namely 2,2'-dipyridylamine (dpa) and N-benzyl-2,2'-dipyridylamine (Bndpa). Hence, complexes [Ru(phen)2(dpa)](PF6)2 (1) and [Ru(phen)2(Bndpa)](PF6)2 (2) were characterized and their photochemical behaviour in solution (acetonitrile and water) was subsequently investigated. Compounds 1 and 2, which do not exhibit notably distorted octahedral coordination environments, contrarily to the homoleptic "parent" compound [Ru(phen)3](PF6)2, experience two-step photoejection of the dpa and Bndpa ligand upon irradiation (1050-430 nm) for several hours. DNA-binding studies revealed that compounds 1 and 2 affect the biomolecule differently upon irradiation; while 2 solely modifies its electrophoretic mobility, complex 1 is also capable of cleaving it. In vitro cytotoxicity studies with two cancer-cell lines, namely A549 (lung adenocarcinoma) and A375 (melanoma), showed that both 1 and 2 are not toxic in the dark, while only 1 is significantly cytotoxic if irradiated, 2 remaining non-toxic under these conditions. Light irradiation of the complex cation [Ru(phen)2(dpa)]2+ leads to the generation of transient Ru species that is present in the solution medium for several hours, and that is significantly cytotoxic, ultimately producing non-toxic free dpa and [Ru(phen)(OH2)2]2+.


Assuntos
Antineoplásicos , Complexos de Coordenação , Rutênio , Complexos de Coordenação/química , Rutênio/farmacologia , Rutênio/química , Ligantes , Antineoplásicos/farmacologia , Antineoplásicos/química
8.
Haematologica ; 108(1): 110-121, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-35770532

RESUMO

Axicabtagene ciloleucel (axi-cel) and tisagenlecleucel (tisa-cel) are CD19-targeted chimeric antigen receptor (CAR) T cells approved for relapsed/refractory (R/R) large B-cell lymphoma (LBCL). We performed a retrospective study to evaluate safety and efficacy of axi-cel and tisa-cel outside the setting of a clinical trial. Data from consecutive patients with R/R LBCL who underwent apheresis for axi-cel or tisa-cel were retrospectively collected from 12 Spanish centers. A total of 307 patients underwent apheresis for axi-cel (n=152) and tisa-cel (n=155) from November 2018 to August 2021, of which 261 (85%) received a CAR T infusion (88% and 82%, respectively). Median time from apheresis to infusion was 41 days for axi-cel and 52 days for tisa-cel (P=0.006). None of the baseline characteristics were significantly different between both cohorts. Both cytokine release syndrome and neurologic events (NE) were more frequent in the axi-cel group (88% vs. 73%, P=0.003, and 42% vs. 16%, P<0.001, respectively). Infections in the first 6 months post-infusion were also more common in patients treated with axi-cel (38% vs. 25%, P=0.033). Non-relapse mortality was not significantly different between the axi-cel and tisa-cel groups (7% and 4%, respectively, P=0.298). With a median follow-up of 9.2 months, median PFS and OS were 5.9 and 3 months, and 13.9 and 11.2 months for axi-cel and tisa-cel, respectively. The 12-month PFS and OS for axi-cel and tisa-cel were 41% and 33% (P=0.195), 51% and 47% (P=0.191), respectively. Factors associated with lower OS in the multivariate analysis were increased lactate dehydrogenase, ECOG ≥2 and progressive disease before lymphodepletion. Safety and efficacy results in our real-world experience were comparable with those reported in the pivotal trials. Patients treated with axi-cel experienced more toxicity but similar non-relapse mortality compared with those receiving tisa-cel. Efficacy was not significantly different between both products.


Assuntos
Imunoterapia Adotiva , Linfoma Difuso de Grandes Células B , Humanos , Proteínas Adaptadoras de Transdução de Sinal , Antígenos CD19 , Imunoterapia Adotiva/efeitos adversos , Linfoma Difuso de Grandes Células B/terapia , Estudos Retrospectivos
9.
Epilepsia ; 64(9): 2260-2273, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37264783

RESUMO

OBJECTIVE: Neurosurgery is a safe and effective form of treatment for select children with drug-resistant epilepsy. Still, there is concern that it remains underutilized, and that seizure freedom rates have not improved over time. We investigated referral and surgical practices, patient characteristics, and postoperative outcomes over the past two decades. METHODS: We performed a retrospective cohort study of children referred for epilepsy surgery at a tertiary center between 2000 and 2018. We extracted information from medical records and analyzed temporal trends using regression analyses. RESULTS: A total of 1443 children were evaluated for surgery. Of these, 859 (402 females) underwent surgical resection or disconnection at a median age of 8.5 years (interquartile range [IQR] = 4.6-13.4). Excluding palliative procedures, 67% of patients were seizure-free and 15% were on no antiseizure medication (ASM) at 1-year follow-up. There was an annual increase in the number of referrals (7%, 95% confidence interval [CI] = 5.3-8.6; p < .001) and surgeries (4% [95% CI = 2.9-5.6], p < .001) over time. Duration of epilepsy and total number of different ASMs trialed from epilepsy onset to surgery were, however, unchanged, and continued to exceed guidelines. Seizure freedom rates were also unchanged overall but showed improvement (odds ratio [OR] 1.09, 95% CI = 1.01-1.18; p = .027) after adjustment for an observed increase in complex cases. Children who underwent surgery more recently were more likely to be off ASMs postoperatively (OR 1.04, 95% CI = 1.01-1.08; p = .013). There was a 17% annual increase (95% CI = 8.4-28.4, p < .001) in children identified to have a genetic cause of epilepsy, which was associated with poor outcome. SIGNIFICANCE: Children with drug-resistant epilepsy continue to be put forward for surgery late, despite national and international guidelines urging prompt referral. Seizure freedom rates have improved over the past decades, but only after adjustment for a concurrent increase in complex cases. Finally, genetic testing in epilepsy surgery patients has expanded considerably over time and shows promise in identifying patients in whom surgery is less likely to be successful.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia , Criança , Feminino , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Epilepsia/diagnóstico , Epilepsia/genética , Epilepsia/cirurgia , Epilepsia Resistente a Medicamentos/diagnóstico , Epilepsia Resistente a Medicamentos/genética , Epilepsia Resistente a Medicamentos/cirurgia , Testes Genéticos
10.
Epilepsia ; 64(8): 2014-2026, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37129087

RESUMO

OBJECTIVE: The accurate prediction of seizure freedom after epilepsy surgery remains challenging. We investigated if (1) training more complex models, (2) recruiting larger sample sizes, or (3) using data-driven selection of clinical predictors would improve our ability to predict postoperative seizure outcome using clinical features. We also conducted the first substantial external validation of a machine learning model trained to predict postoperative seizure outcome. METHODS: We performed a retrospective cohort study of 797 children who had undergone resective or disconnective epilepsy surgery at a tertiary center. We extracted patient information from medical records and trained three models-a logistic regression, a multilayer perceptron, and an XGBoost model-to predict 1-year postoperative seizure outcome on our data set. We evaluated the performance of a recently published XGBoost model on the same patients. We further investigated the impact of sample size on model performance, using learning curve analysis to estimate performance at samples up to N = 2000. Finally, we examined the impact of predictor selection on model performance. RESULTS: Our logistic regression achieved an accuracy of 72% (95% confidence interval [CI] = 68%-75%, area under the curve [AUC] = .72), whereas our multilayer perceptron and XGBoost both achieved accuracies of 71% (95% CIMLP = 67%-74%, AUCMLP = .70; 95% CIXGBoost own = 68%-75%, AUCXGBoost own = .70). There was no significant difference in performance between our three models (all p > .4) and they all performed better than the external XGBoost, which achieved an accuracy of 63% (95% CI = 59%-67%, AUC = .62; pLR = .005, pMLP = .01, pXGBoost own = .01) on our data. All models showed improved performance with increasing sample size, but limited improvements beyond our current sample. The best model performance was achieved with data-driven feature selection. SIGNIFICANCE: We show that neither the deployment of complex machine learning models nor the assembly of thousands of patients alone is likely to generate significant improvements in our ability to predict postoperative seizure freedom. We instead propose that improved feature selection alongside collaboration, data standardization, and model sharing is required to advance the field.


Assuntos
Epilepsia , Criança , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Epilepsia/diagnóstico , Epilepsia/cirurgia , Convulsões/diagnóstico , Convulsões/cirurgia , Aprendizado de Máquina
11.
Eur J Haematol ; 111(1): 146-153, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37058419

RESUMO

OBJECTIVES: High-dose total body irradiation (TBI) is considered a cornerstone of myeloablative conditioning for allogeneic stem cell transplantation (allo-SCT). We retrospectively compared the main outcomes of an HLA matched or 1-allele mismatched related or unrelated allo-SCT in adult patients affected by acute leukemia (AL) or myelodysplastic syndromes (MDS). METHODS: Fifty-nine patients received cyclophosphamide (Cy)-TBI (13.5 Gy) and graft-versus-host disease (GVHD) prophylaxis with a calcineurin-inhibitor plus methrotrexate (CyTBI group) and 28 patients received fludarabine-TBI (8.8-13.5 Gy) and GVHD prophylaxis with PTCy and tacrolimus (FluTBI-PTCy group). RESULTS: Median follow-up for survivors was 82 and 22 months. The 12-month probability of overall survival and progression-free survival were similar (p = .18, p = .7). The incidence of Grades 2-4 and 3-4 acute GVHD, and the incidence of moderate-to-severe chronic GVHD were higher in the CyTBI group (p = .02, p < .01and p = .03). Nonrelapse mortality (NRM) at 12 months posttransplant was higher in the CyTBI group (p = 0.05), while the incidence of relapse was similar in both groups (p = 0.7). The number of GVHD-free and relapse-free patients without systemic immunosuppression (GRFS) at 1-year posttransplant was higher in the FluTBI-PTCy group (p = 0.01). CONCLUSIONS: The study confirms the safety and efficacy of a novel FluTBI-PTCy platform with reduced incidence of severe acute and chronic GVHD, and early improvement of NRM.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Adulto , Humanos , Estudos Retrospectivos , Irradiação Corporal Total , Ciclofosfamida/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Doença Enxerto-Hospedeiro/diagnóstico , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/prevenção & controle , Leucemia Mieloide Aguda/tratamento farmacológico , Recidiva , Condicionamento Pré-Transplante
12.
Angew Chem Int Ed Engl ; 62(5): e202215163, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36345831

RESUMO

The trapping of the elusive vinylogous position of a vinyl carbene with an aliphatic C(sp3 )-H bond has been achieved for the first time during a silver-catalyzed carbene/alkyne metathesis (CAM) process. A Tpx -containing silver complex first promotes the generation of a donor-acceptor silver carbene which triggers CAM, generating a subsequent donor-donor vinyl silver carbene species, which then undergoes a selective vinylogous C(sp3 )-H bond insertion, leading to the synthesis of a new family of benzoazepines. Density functional theory (DFT) calculations unveil the reaction mechanism, which allows proposing that the C-H bond insertion reaction takes place in a stepwise manner, with the hydrogen shift being the rate determining step.

13.
J Biol Inorg Chem ; 26(6): 727-740, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34453615

RESUMO

Two square-planar coordination compounds, namely [Cu(CPYA)Cl2] (1) and [Pd(CPYA)Cl2] (2), were prepared from the ligand 4-chloro-N-(pyridin-2-ylmethyl)aniline (CPYA) and two chloride salts, and were fully characterized, including by X-ray diffraction. Spectroscopic, electrophoretic and AFM studies revealed that the two isostructural compounds were interacting differently with DNA. In both cases, the initial interaction involves electrostatic contacts of the CPYA ligand in the minor groove (as suggested by molecular docking), but subsequent strong binding occurs with the palladium(II) complex 2, whereas the binding with the copper complex 1 is weaker and concentration dependent. The strong binding of 2 eventually leads to the cleavage of the double strand and the redox activity of 1 allows to oxidatively cleave the biomolecule.


Assuntos
Cloretos/química , Cobre/química , DNA/química , Paládio/química , Dicroísmo Circular , Cristalografia por Raios X , Corantes Fluorescentes , Ligação de Hidrogênio , Modelos Moleculares , Estrutura Molecular
14.
Biomacromolecules ; 22(2): 430-440, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33416315

RESUMO

Alzheimer's disease (AD), affecting almost 50 million individuals worldwide, is currently the first cause of dementia. Despite the tremendous research efforts in the last decade, only four supportive or palliative drugs, namely, acetylcholinesterase (AChE) inhibitors donepezil, galantamine, and rivastigmine and the glutamate NMDA receptor antagonist memantine, are currently available. New therapeutic strategies are becoming prominent, such as the direct inhibition of amyloid formation or the regulation of metal homeostasis. In the present report, the potential use of Prussian blue (PB), a drug that is in the World Health Organization Model List of Essential Medicines, in AD treatment is demonstrated. Both in vitro and in cellulo studies indeed suggest that PB nanoparticles (PBNPs) are capable of reducing the formation of typical amyloid-ß fibers (detected by thioflavin T fluorescence) and restoring the usual amyloid fibrillation pathway via chelation/sequestration of copper, which is found in high concentrations in senile plaques.


Assuntos
Doença de Alzheimer , Nanopartículas , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides , Cobre , Ferrocianetos , Humanos , Conformação Proteica em Folha beta
15.
Angew Chem Int Ed Engl ; 60(1): 41-52, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-32706460

RESUMO

The generation of highly organized amyloid fibrils is associated with a wide range of conformational pathologies, including primarily neurodegenerative diseases. Such disorders are characterized by misfolded proteins that lose their normal physiological roles and acquire toxicity. Recent findings suggest that proteostasis network impairment may be one of the causes leading to the accumulation and spread of amyloids. These observations are certainly contributing to a new focus in anti-amyloid drug design, whose efforts are so far being centered on single-target approaches aimed at inhibiting amyloid aggregation. Chaperones, known to maintain proteostasis, hence represent interesting targets for the development of novel therapeutics owing to their potential protective role against protein misfolding diseases. In this minireview, research on nanoparticles that can either emulate or help molecular chaperones in recognizing and/or correcting protein misfolding is discussed. The nascent concept of "nanochaperone" may indeed set future directions towards the development of cost-effective, disease-modifying drugs to treat several currently fatal disorders.


Assuntos
Chaperonas Moleculares/química , Agregados Proteicos/genética , Deficiências na Proteostase/genética , Humanos , Conformação Molecular , Dobramento de Proteína , Deficiências na Proteostase/patologia
16.
Angew Chem Int Ed Engl ; 60(34): 18467-18471, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-33979475

RESUMO

The functionalization of C-H bonds in light alkanes, particularly to form C-N bonds, remains a challenge. We report the dehydrogenative coupling of amides with C1-C4 hydrocarbons to form N-alkyl amide products with tBuOOtBu as oxidant, and a copper complex of a phenanthroline-type ligand as catalyst. The reactions occurred in good yields in benzene or supercritical carbon dioxide as solvents. This strategy allowed for the determination of the relative reactivity of these alkane C-H bonds toward this amination process and showed, in contrast to prior work with larger alkanes, that the reactivity correlated with bond dissociation energies.

17.
Circulation ; 140(5): 405-419, 2019 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-31155924

RESUMO

BACKGROUND: Catecholaminergic polymorphic ventricular tachycardia (CPVT), an inherited cardiac arrhythmia characterized by adrenergically triggered arrhythmias, is inadequately treated by current standard of care. Ca2+/calmodulin-dependent protein kinase II (CaMKII), an adrenergically activated kinase that contributes to arrhythmogenesis in heart disease models, is a candidate therapeutic target in CPVT. However, translation of CaMKII inhibition has been limited by the need for selective CaMKII inhibition in cardiomyocytes. Here, we tested the hypothesis that CaMKII inhibition with a cardiomyocyte-targeted gene therapy strategy would suppress arrhythmia in CPVT mouse models. METHODS: We developed AAV9-GFP-AIP, an adeno-associated viral vector in which a potent CaMKII inhibitory peptide, autocamtide-2-related inhibitory peptide [AIP], is fused to green fluorescent protein (GFP) and expressed from a cardiomyocyte selective promoter. The vector was delivered systemically. Arrhythmia burden was evaluated with invasive electrophysiology testing in adult mice. AIP was also tested on induced pluripotent stem cells derived from patients with CPVT with different disease-causing mutations to determine the effectiveness of our proposed therapy on human induced pluripotent stem cell-derived cardiomyocytes and different pathogenic genotypes. RESULTS: AAV9-GFP-AIP was robustly expressed in the heart without significant expression in extracardiac tissues, including the brain. Administration of AAV9-GFP-AIP to neonatal mice with a known CPVT mutation (RYR2R176Q/+) effectively suppressed ventricular arrhythmias induced by either ß-adrenergic stimulation or programmed ventricular pacing, without significant proarrhythmic effect. Intravascular delivery of AAV9-GFP-AIP to adolescent mice transduced ≈50% of cardiomyocytes and was effective in suppressing arrhythmia in CPVT mice. Induced pluripotent stem cell-derived cardiomyocytes derived from 2 different patients with CPVT with different pathogenic mutations demonstrated increased frequency of abnormal calcium release events, which was suppressed by a cell-permeable form of AIP. CONCLUSIONS: This proof-of-concept study showed that AAV-mediated delivery of a CaMKII peptide inhibitor to the heart was effective in suppressing arrhythmias in a murine model of CPVT. CaMKII inhibition also reversed the arrhythmia phenotype in human CPVT induced pluripotent stem cell-derived cardiomyocyte models with different pathogenic mutations.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Terapia Genética/métodos , Taquicardia Ventricular/genética , Taquicardia Ventricular/terapia , Adenoviridae/genética , Animais , Animais Recém-Nascidos , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Células Cultivadas , Camundongos , Camundongos Transgênicos , Taquicardia Ventricular/enzimologia
18.
Ann Hematol ; 99(1): 157-165, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31844931

RESUMO

Haploidentical related (Haplo) and umbilical cord blood (UCB) donors are the main "alternative donor" options for allogeneic hematopoietic stem cell transplantation (HCT) for patients without identical donor. At our institution, UCB was the main alternative donor type until 2013, when HaploHCT was introduced as the preferred procedure. A common myeloablative conditioning regimen was used, based on thiotepa, busulfan, and fludarabine. We analyze the outcomes of 47 patients (61%) who received a single UCB transplantation (UCBT) and 30 patients (39%) who received a HaploHCT with post-transplant cyclophosphamide. No differences were found in the rate of neutrophil engraftment, whereas platelet recovery was earlier with HaploHCT. NRM was higher after UCBT at 3 months and 3 years (13% and 13% vs. 23% and 45% in HaploHCT and UCBT, respectively; p < 0.001 for both time points). The 3-year relapse incidence was 35% after HaploHCT vs. 17% after UCBT, respectively (p = 0.13). The 100-day incidence of grade 3-4 acute GVHD (3% vs. 11%) and the 3-year moderate-to-severe chronic GVHD (4% vs. 15%) did not differ between HaploHCT and UCBT, respectively (p > 0.2). There was a trend for higher overall survival at 1 and 3 years in HaploHCT recipients (69% vs. 45% and 64% vs. 38%, respectively; p = 0.055 for both time points). Despite the small sample sizes, multivariate analysis adjusted for patient age and disease status at transplant showed a better 3-year OS in HaploHCT recipients, mostly due to a lower NRM (p < 0.001). Our results support the use of HaploHCT when feasible when an identical donor is not available.


Assuntos
Bussulfano/administração & dosagem , Transplante de Células-Tronco de Sangue do Cordão Umbilical , Antígenos HLA , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco de Sangue Periférico , Tiotepa/administração & dosagem , Condicionamento Pré-Transplante , Vidarabina/análogos & derivados , Adulto , Idoso , Aloenxertos , Feminino , Neoplasias Hematológicas/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Vidarabina/administração & dosagem
19.
Inorg Chem ; 59(1): 837-846, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31855423

RESUMO

Competitive Cu(II)-binding studies have been carried out between five decapeptides (both acyclic and cyclic), namely C-Asp, C-Asn, O-Asp, ODPro-Asp, and O-Asn, and the Aß(1-16) and Aß(1-40) fragments. Conformational constraints in such peptidic scaffolds affect their copper-binding affinity, which can be tuned. In the present study, the ability of these peptides to compete with Aß has been assessed in vitro, with the objective to examine whether such soft chelating agents may be used to lessen the deleterious interaction of Cu(II) with Aß. Fluorescence spectroscopy, electron paramagnetic resonance, and mass spectrometry data show that the more constrained peptide, i.e., cyclic C-Asp, which displays a Cu(II)-binding affinity comparable to that of Aß, is the only potential metal-protein attenuating compound (MPAC) candidate. In vitro aggregation studies with Aß(1-40) reveal that C-Asp can hamper the formation of copper-stabilized oligomeric Aß species, through capturing the metal ion prior to its interaction with monomeric Aß. The present study shows that (cyclic) peptides, preorganized for Cu(II) binding, may be applied for the development of potential copper-Aß attenuating compounds.


Assuntos
Peptídeos beta-Amiloides/antagonistas & inibidores , Cobre/química , Peptídeos Cíclicos/farmacologia , Peptídeos beta-Amiloides/química , Cinética , Modelos Moleculares , Estrutura Molecular , Peptídeos Cíclicos/química , Agregados Proteicos/efeitos dos fármacos
20.
Inorg Chem ; 59(10): 6978-6987, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32369695

RESUMO

Three thiosemicarbazone derivatives, namely 4-(dimethylamino)benzaldehyde 4,4-dimethylthiosemicarbazone (HL1), 4-(dimethylamino)benzaldehyde thiosemicarbazone (HL2), and 4-(dimethylamino)benzaldehyde 4-methylthiosemicarbazone (HL3), have been synthesized and characterized. The three palladium(II) complexes 1-3 were prepared respectively from HL1, HL2, and HL3. The crystal structures of two coordination compounds, namely Pd(L2)2 (2) and Pd(L3)2 (3), were obtained, which showed the expected square-planar environment for the metal centers. The ligand HL3 and the Pd(II) complexes 1-3, which are stable in buffered solutions containing up to 5% DMSO, exhibit remarkable inhibitory properties against the aggregation of amyloid-ß, reducing the formation of fibrils. HL1, HL3, 2, and 3 display IC50 values (i.e., the concentrations required to reduce Aß fibrillation by 50%) below 1 µM, lower that of the reference compound catechin (IC50 = 2.8 µM). Finally, in cellulo studies with E. coli cells revealed that the palladium(II) compounds are significantly more efficient than the free ligands in inhibiting Aß aggregation inside bacterial inclusion bodies, thus illustrating a beneficial effect of metal coordination.


Assuntos
Peptídeos beta-Amiloides/antagonistas & inibidores , Complexos de Coordenação/farmacologia , Platina/farmacologia , Tiossemicarbazonas/farmacologia , Peptídeos beta-Amiloides/metabolismo , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Cristalografia por Raios X , Escherichia coli/citologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Modelos Moleculares , Estrutura Molecular , Platina/química , Agregados Proteicos/efeitos dos fármacos , Tiossemicarbazonas/química
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