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1.
Blood Adv ; 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39388660

RESUMO

Mutations commonly associated with acute myeloid leukemia (AML), such as CEBPA, FLT3, IDH1/2 and NPM1 are rarely found in chronic myelomonocytic leukemia (CMML) and their prognostic significance in CMML has not been clearly identified. In 127 CMML patients, we have retrospectively analyzed next-generation sequencing and PCR data from analyses of bone marrow samples performed at diagnosis of CMML. Seven patients harbored CEBPA mutations, eight FLT3 mutations, 12 IDH1 mutations, 26 IDH2 mutations and 11 NPM1 mutations. CMML patients harboring CEBPA, FLT3, and/or NPM1 mutations (mutCFN)were more frequently associated with the myeloproliferative subtype (MP-CMML) , a high prevalence of severe cytopenia, and elevated blast counts. Regardless of their CPSS-Mol classification, mutCFN CMML patients had a poor prognosis, and the multivariate analysis identified mutCFN as an independent marker of overall survival. The genetic profile of these mutCFN CMML patients closely resembled that of AML, with higher-risk clinical characteristics. Our findings lead us to suggest including the assessment of these mutations in CMML prognostic models and treating these patients with AML-type therapies, including intensive chemotherapy and allogeneic stem cell transplantation, whenever feasible, and consider certain targeted therapies approved for use in AML.

2.
Nat Commun ; 15(1): 8697, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39379386

RESUMO

Safe storage and utilisation of hydrogen is an ongoing area of research, showing potential to enable hydrogen becoming an effective fuel, substituting current carbon-based sources. Hydrogen storage is associated with a high energy cost due to its low density and boiling point, which drives a high price. Clathrates (gas hydrates) are water-based (ice-like) structures incorporating small non-polar compounds such as H2 in cages formed by hydrogen bonded water molecules. Since only water is required to construct the cages, clathrates have been identified as a potential solution for safe storage of hydrogen. In bulk, pure hydrogen clathrate (H2O-H2) only forms in harsh conditions, but confined in nanospaces the properties of water are altered and hydrogen storage at mild pressure and temperature could become possible. Here, specifically a hydrophobic mesoporous silica is proposed as a host material, providing a suitable nano-confinement for ice-like clathrate hydrate. The hybrid silica material shows an important decrease of the pressure required for clathrate formation (approx. 20%) compared to the pure H2O-H2 system. In-situ inelastic neutron scattering (INS) and neutron diffraction (ND) provided unique insights into the interaction of hydrogen with the complex surface of the hybrid material and demonstrated the stability of nano-confined hydrogen clathrate hydrate.

3.
Chem Mater ; 36(18): 8763-8772, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39347470

RESUMO

Noble metal nanoparticles, particularly gold and silver nanoparticles, have garnered significant attention due to their ability to manipulate light at the nanoscale through their localized surface plasmon resonance (LSPR). While their LSPRs below 1100 nm were extensively exploited in a wide range of applications, their potential in the near-infrared (NIR) region, crucial for optical communication and sensing, remains relatively underexplored. One primary reason is likely the limited strategies available to obtain highly stable plasmonic nanoparticles with tailored optical properties in the NIR region. Herein, we synthesized AuAg nanorattles (NRTs) with tailored and narrow plasmonic responses ranging from 1000 to 3000 nm. Additionally, we performed comprehensive characterization, employing advanced electron microscopy and various spectroscopic techniques, coupled with finite difference time domain (FDTD) simulations, to elucidate their optical properties. Notably, we unveiled the main external and internal LSPR modes by combining electron energy-loss spectroscopy (EELS) with surface-enhanced Raman scattering (SERS). Furthermore, we demonstrated through surface-enhanced infrared absorption spectroscopy (SEIRA) that the NRTs can significantly enhance the infrared signals of a model molecule. This study not only reports the synthesis of plasmonic NRTs with tunable LSPRs over the entire NIR range but also demonstrates their potential for NIR sensing and optical communication.

4.
Oncologist ; 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39349391

RESUMO

The 2022 WHO revision and the ICC classification have recently modified the diagnostic criteria for chronic myelomonocytic leukemia (CMML) and acute myeloid leukemia. However, there is no consensus on whether CMML with NPM1 mutation (NPM1mut) should be diagnosed as AML. Nowadays, it is a subject of discussion because of its diagnostic and therapeutic implications. Therefore, we describe a case of a patient diagnosed with CMML NPM1mut and briefly review the literature to highlight the uncertainty about how to classify a CMML with NPM1 mutation. We emphasize the importance of a comprehensive molecular study, which is crucial to optimize the individualized treatment of patients, enabling them to access targeted therapies.

5.
Nanoscale ; 16(34): 16107-16118, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39099555

RESUMO

We demonstrate the first successful functionalization of epitaxial three-dimensional graphene with metal nanoparticles. The functionalization is obtained by immersing three-dimensional graphene in a nanoparticle colloidal solution. This method is versatile and demonstrated here for gold and palladium, but can be extended to other types of nanoparticles. We have measured the nanoparticle density on the top surface and in the porous layer volume by scanning electron microscopy and scanning transmission electron microscopy. The samples exhibit a wide coverage of nanoparticles with minimal clustering. We demonstrate that high-quality graphene promotes the functionalization, leading to higher nanoparticle density both on the surface and in the pores. X-ray photoelectron spectroscopy shows the absence of contamination after the functionalization process. Moreover, it confirms the thermal stability of the Au- and Pd-functionalized three-dimensional graphene up to 530 °C. Our approach opens new avenues for utilizing three-dimensional graphene as a versatile platform for catalytic applications, sensors, and energy storage and conversion.

6.
Chem Mater ; 36(14): 6865-6876, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39070672

RESUMO

Self-assembled magnetic nanoparticles offer next-generation materials that allow harnessing of their physicochemical properties for many applications. However, how three-dimensional nanoassemblies of magnetic nanoparticles can be synthesized in one-pot synthesis without excessive postsynthesis processes is still a bottleneck. Here, we propose a panel of small organic molecules that glue nanoparticle crystallites during the growth of particles to form large nanoassembled nanoparticles (NANs). We find that both carbonyl and carboxyl functional groups, presenting in benzaldehyde and benzoic acid, respectively, are needed to anchor with metal ions, while aromatic rings are needed to create NANs through π-π stacking. When benzyl alcohol, lacking carbonyl and carboxyl groups, is employed, no NANs are formed. NANs formed by benzoic acid reveal a unique combination of high magnetization and coercivity, whereas NANs formed by benzaldehyde show the largest exchange bias reported in nanoparticles. Surprisingly, our NANs show unconventional colloidal stability due to their unique nanoporous architectures.

7.
Nat Commun ; 15(1): 6399, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080248

RESUMO

Electron tomography has become a commonly used tool to investigate the three-dimensional (3D) structure of nanomaterials, including colloidal nanoparticle assemblies. However, electron microscopy is typically done under high-vacuum conditions, requiring sample preparation for assemblies obtained by wet colloid chemistry methods. This involves solvent evaporation and deposition on a solid support, which consistently alters the nanoparticle organization. Here, we suggest using electron tomography to study nanoparticle assemblies in their original colloidal liquid environment. To address the challenges related to electron tomography in liquid, we devise a method that combines fast data acquisition in a commercial liquid-cell with a dedicated alignment and reconstruction workflow. We present the advantages of this methodology in accurately characterizing two different systems. 3D reconstructions of assemblies comprising polystyrene-capped Au nanoparticles encapsulated in polymeric shells reveal less compact and more distorted configurations for experiments performed in a liquid medium compared to their dried counterparts. A similar expansion can be observed in quantitative analysis of the surface-to-surface distances of self-assembled Au nanorods in water rather than in a vacuum, in agreement with bulk measurements. This study, therefore, emphasizes the importance of developing high-resolution characterization tools that preserve the native environment of colloidal nanostructures.

8.
J Colloid Interface Sci ; 672: 600-609, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38857568

RESUMO

Solar-light driven oxidation of benzylic alcohols over photocatalysts endows significant prospects in value-added organics evolution owing to its facile, inexpensive and sustainable process. However, the unsatisfactory performance of actual photocatalysts due to the inefficient charge separation, low photoredox potential and sluggish surface reaction impedes the practical application of this process. Herein, we developed an innovative Z-Scheme Cs3BiBr9 nanoparticles@porous C3N4 tubes (CBB-NP@P-tube-CN) heterojunction photocatalyst for highly selective benzyl alcohol oxidation. Such composite combining increased photo-oxidation potential, Z-Scheme charge migration route as well as the structural advantages of porous tubular C3N4 ensures the accelerated mass and ions diffusion kinetics, the fast photoinduced carriers dissociation and sufficient photoredox potentials. The CBB-NP@P-tube-CN photocatalyst demonstrates an exceptional performance for selective photo-oxidation of benzylic alcohol into benzaldehyde with 19, 14 and 3 times higher benzylic alcohols conversion rate than those of C3N4 nanotubes, Cs3Bi2Br9 and Cs3Bi2Br9@bulk C3N4 photocatalysts, respectively. This work offers a sustainable photocatalytic system based on lead-free halide perovskite toward large scale solar-light driven value-added chemicals production.

9.
Adv Mater ; 36(26): e2314056, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38618981

RESUMO

A thorough and quantitative understanding of the fate of excitons in covalent-organic frameworks (COFs) after photoexcitation is essential for their augmented optoelectronic and photocatalytic applications via precise structure tuning. The synthesis of a library of COFs having identical chemical backbone with impeded conjugation, but varied morphology and surface topography to study the effect of these physical properties on the photophysics of the materials is herein reported. The variation of crystallite size and surface topography substantified different aggregation pattern in the COFs, which leads to disparities in their photoexcitation and relaxation properties. Depending on aggregation, an inverse correlation between bulk luminescence decay time and exciton binding energy of the materials is perceived. Further transient absorption spectroscopic analysis confirms the presence of highly localized, immobile, Frenkel excitons (of diameter 0.3-0.5 nm) via an absence of annihilation at high density, most likely induced by structural torsion of the COF skeletons, which in turn preferentially relaxes via long-lived (nanosecond to microsecond) excimer formation (in femtosecond scale) over direct emission. These insights underpin the importance of structural and topological design of COFs for their targeted use in photocatalysis.

11.
Clin Transl Sci ; 17(3): e13742, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38494922

RESUMO

Relapsed/refractory (r/r) acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) outcomes remain poor. A targeted cluster of differentiation (CD)33 × CD3 bispecific antibody, JNJ-67571244, was assessed to identify the maximum tolerated dose (MTD), recommended phase II dose (RP2D), safety and tolerability, and preliminary clinical activity in patients with r/rAML or r/rMDS. This first-in-human, open-label, phase I, dose-escalation/dose-expansion study included patients with r/rAML or r/rMDS who were ineligible for or had exhausted standard therapeutic options. JNJ-67571244 was administered intravenously or subcutaneously using step-up dosing until ≥1 discontinuation condition was met. Outcomes included safety/tolerability, preliminary clinical activity, and systemic pharmacokinetics and pharmacodynamics. The study was terminated after evaluating 10 dose-escalation cohorts (n = 68) and before starting dose-expansion. Overall, 11 (16.2%) patients experienced ≥1 dose-limiting toxicity; all experienced ≥1 treatment-emergent adverse event (TEAE; treatment related: 60 [88.2%]); and 64 (94.1%) experienced ≥1 TEAE of Grade ≥3 toxicity (treatment related: 28 [41.2%]). Although some patients had temporary disease burden reductions, no responses were seen. JNJ-67571244 administration increased multiple cytokines, which coincided with incidence of cytokine release syndrome, infusion-related reactions, and elevated liver function tests. A prolonged step-up strategy was tested to improve tolerability, though this approach did not prevent hepatotoxicity. T-cell activation following treatment suggested target engagement but did not correlate with clinical activity. Safely reaching the projected exposure level for JNJ-67571244 efficacy was not achieved, thus MTD and RP2D were not determined.


Assuntos
Antineoplásicos , Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Humanos , Antineoplásicos/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Síndromes Mielodisplásicas/tratamento farmacológico , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico/imunologia
12.
Br J Haematol ; 204(3): 892-897, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38013238

RESUMO

Recently modified diagnostic criteria for chronic myelomonocytic leukaemia (CMML) have lowered the cut-off for absolute monocytosis. In the largest series to date, we have analysed 313 CMML patients, including 104 with oligomonocytic (OM)-CMML. Five-year survival was longer for OM-CMML than for other patients (p < 0.001). Multivariate analysis identified OM-CMML as a favourable prognostic factor (HR 0.58; p = 0.002). The 5-year cumulative incidence of progression to classical CMML was 47%. Older age and transfusion dependence were adverse prognostic factors for OM-CMML. Our results support the inclusion of OM-CMML in the CMML category as a subtype with superior outcomes.


Assuntos
Leucemia Mielomonocítica Crônica , Humanos , Leucemia Mielomonocítica Crônica/diagnóstico , Leucocitose , Prognóstico
13.
An. Fac. Cienc. Méd. (Asunción) ; 56(3): 118-120, 20231201.
Artigo em Espanhol | LILACS | ID: biblio-1519423

RESUMO

Actualmente existe una tendencia mundial de desplazamiento de la población rural hacia áreas cada vez más urbanizadas. Existe evidencia que informa que el desarrollo de las enfermedades mentales tiene relación importante con factores tanto internos (por ejemplo, genéticos) y externos (el ambiente, entre otros). Con respecto a esto último, la manera en la que el entorno afecta a la salud mental es un objeto de estudio de interés global y se ha reportado que las áreas urbanas presentan mayores tasas de trastornos mentales comunes en comparación con las rurales. En el caso de la psicosis, por más de que el factor genético sea el más demostrado (y estudiado en los últimos años), el factor ambiental representando por el ambiente urbano ya ha sido analizado por investigadores a inicios del siglo 20. Desde allí, a lo largo de los años se obtuvo evidencia repetida que lo respalda como un factor de riesgo. Se ha encontrado que, además, existe relación con el grado de exposición, lo que hace pensar que la causa no solamente se limita a la transición del área rural al área urbana, sino que están involucrados factores sociales, económicos y medioambientales más profundos como la disparidad social, inseguridad, contaminación, entre otros 1. Ya en las últimas décadas del siglo 20, investigadores informaron de un aumento de la incidencia de esquizofrenia de 1,65 en hombres que vivían ciudades sobre sus contrapartes de origen rural. Años después, otros estudios han reportado esta variación en la incidencia de primeros episodios psicóticos a través del gradiente social urbano-rural, así como una relación entre el aumento de hospitalización por esquizofrenia con el grado de urbanización.

15.
Int. j. morphol ; 41(5): 1480-1484, oct. 2023. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1521043

RESUMO

Testut & Latarjet (1980), Bouchet & Cuilleret (1986), Latarjet & Liard (2005) y Rouvière & Delmas (2005) describen las relaciones intrínsecas del pedículo renal (PR) a partir de dos planos coronales, siendo la PER el elemento que limita entre ambos. Trivedi et al. (2011) demostró relaciones entre los elementos del PR que no coinciden con las descripciones aportadas por dichos autores.Conocer las posibles variantes en las relaciones intrínsecas del PR es de suma importancia en prácticas quirúrgicas como el trasplante renal (García de Jalón Martínez et al., 2003; Batista Hernández et al., 2010). Por lo tanto, el objetivo del presente trabajo fue analizar las variables relaciones entre los elementos que conforman el PR en la región yuxtahiliar del riñón. Se estudiaron 23 PR, formolizados al 10 % y provistos por el Equipo de Disección de la Segunda Cátedra de Anatomía de la Universidad de Buenos Aires. Se clasificaron los PR en dos grupos. En el Grupo I, las afluentes de origen de la vena renal (AOVR) se hallaban en el mismo plano coronal. En el grupo II, las AOVR se encontraban en diferentes planos coronales. Cada grupo fue subdividido en distintos patrones. Los patrones I y II, de mayor incidencia, fueron asociados al grupo I y los patrones III, IV y V al grupo II. En el patrón I, las AOVR eran anteriores a la pelvis renal (PER) y posteriores a la arteria prepiélica (APP). En el patrón II, las AOVR eran anteriores a la PER y a la APP. Los patrones I y II conforman el grupo I y presentaron mayor número de incidencia en nuestra investigación. Existen también variantes que inciden con menor frecuencia que dichos patrones, estas comprenden el grupo II de la clasificación planteada en el presente trabajo.


SUMMARY: Testut & Latarjet (1980), Bouchet & Cuilleret (1986), Latarjet & Liard (2005) y Rouvière & Delmas (2005) describe the intrinsic relationships of the renal pedicle (PR) from two coronal planes, the renal pelvis (PER) being the element that limits between both. Trivedi et al. (2011) showed relationships between the elements of the RP that do not coincide with the descriptions provided by these authors. Knowing the possible variants in the intrinsic relationships of the RP is of the utmost importance in surgical practices such as renal transplantation (García de Jalón Martínez et al., 2003). Therefore, the objective of this study is to analyze the variable relationships between the elements that make up the RP in the juxtahilar region of the kidney. 23 RP were studied, formalized at 10 % and provided by the Dissection Team of the Second Chair of Anatomy of the University of Buenos Aires. PRs were classified into two groups. In Group I, the tributaries of origin of the renal vein (RVOA) were in the same coronal plane. In group II, the AOVRs were in different coronal planes. Each group was subdivided into different patterns. Patterns I and II, with the highest incidence, were associated with group I and patterns III, IV and V with group II. In pattern I, the VROA were anterior to the renal pelvis (PER) and posterior to the prepelvic artery (PPA). In pattern II, AOVRs were prior to PER and APP. Patterns I and II make up group I and presented a higher number of incidence in our investigation. There are also variants that occur less frequently than these patterns, these comprise group II of the classification proposed in this work.


Assuntos
Humanos , Artéria Renal/anatomia & histologia , Veias Renais/anatomia & histologia , Pelve Renal , Cadáver , Variação Anatômica , Rim
16.
Chemphyschem ; 24(22): e202300437, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37669423

RESUMO

The hydrolysis of the phosphonate ester linker during the synthesis of hybrid (organic-inorganic) TiO2 nanoparticles is important when forming porous hybrid organic-inorganic metal phosphonates. In the present work, a method was utilized to control the in-situ partial hydrolysis of diphosphonate ester in the presence of a titania precursor as a function of acid content, and its impact on the hybrid nanoparticles was assessed. Organodiphosphonate esters, and more specific, their hydrolysis degree during the formation of hybrid organic-inorganic metal oxide nanoparticles, are relatively under explored as linkers. Here, a detailed analysis on the hydrolysis of tetraethyl propylene diphosphonate ester (TEPD) as diphosphonate linker to produce hybrid TiO2 nanoparticles is discussed as a function of acid content. Quantitative solution NMR spectroscopy revealed that during the synthesis of TiO2 nanoparticles, an increase in acid concentration introduces a higher degree of partial hydrolysis of the TEPD linker into diverse acid/ester derivatives of TEPD. Increasing the HCl/Ti ratio from 1 to 3, resulted in an increase in degree of partial hydrolysis of the TEPD linker in solution from 4 % to 18.8 % under the applied conditions. As a result of the difference in partial hydrolysis, the linker-TiO2 bonding was altered. Upon subsequent drying of the colloidal TiO2 solution, different textures, at nanoscale and macroscopic scale, were obtained dependent on the HCl/Ti ratio and thus the degree of hydrolysis of TEPD. Understanding such linker-TiO2 nanoparticle surface dynamics is crucial for making hybrid organic-inorganic materials (i. e. (porous) metal phosphonates) employed in applications such as electronic/photonic devices, separation technology and heterogeneous catalysis.

19.
ACS Nano ; 17(17): 16943-16951, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37602824

RESUMO

Rhodium-platinum core-shell nanoparticles on a carbon support (Rh@Pt/C NPs) are promising candidates as anode catalysts for polymer electrolyte membrane fuel cells. However, their electrochemical stability needs to be further explored for successful application in commercial fuel cells. Here we employ identical location scanning transmission electron microscopy to track the morphological and compositional changes of Rh@Pt/C NPs during potential cycling (10 000 cycles, 0.06-0.8 VRHE, 0.5 H2SO4) down to the atomic level, which are then used for understanding the current evolution occurring during the potential cycles. Our results reveal a high stability of the Rh@Pt/C system and point toward particle detachment from the carbon support as the main degradation mechanism.

20.
Heliyon ; 9(7): e17662, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37449178

RESUMO

Biomethane is a renewable natural gas substitute produced from biogas. Storage of this sustainable energy vector in confined clathrate hydrates, encapsulated in the pores of a host material, is a highly promising avenue to improve storage capacity and energy efficiency. Herein, a new type of periodic mesoporous organosilica (PMO) nanotubes, referred to as hollow ring PMO (HR-PMO), capable of promoting methane clathrate hydrate formation under mild working conditions (273 K, 3.5 MPa) and at high water loading (5.1 g water/g HR-PMO) is reported. Gravimetric uptake measurements reveal a steep single-stepped isotherm and a noticeably high methane storage capacity (0.55 g methane/g HR-PMO; 0.11 g methane/g water at 3.5 MPa). The large working capacity throughout consecutive pressure-induced clathrate hydrate formation-dissociation cycles demonstrates the material's excellent recyclability (97% preservation of capacity). Supported by ex situ cryo-electron tomography and x-ray diffraction, HR-PMO nanotubes are hypothesized to promote clathrate hydrate nucleation and growth by distribution and confinement of water in the mesopores of their outer wall, along the central channels of the nanotubes and on the external nanotube surface. These findings showcase the potential for application of organosilica materials with hierarchical and interconnected pore systems for pressure-based storage of biomethane in confined clathrate hydrates.

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