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1.
Biomolecules ; 14(3)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38540668

RESUMO

The PTEN-induced kinase 1 (PINK1)-Parkin pathway plays a vital role in maintaining a healthy pool of mitochondria in higher eukaryotic cells. While the downstream components of this pathway are well understood, the upstream triggers remain less explored. In this study, we conducted an extensive analysis of inhibitors targeting various mitochondrial electron transport chain (ETC) complexes to investigate their potential as activators of the PINK1-Parkin pathway. We identified cloflucarban, an antibacterial compound, as a novel pathway activator that simultaneously inhibits mitochondrial complexes III and V, and V. RNA interference (RNAi) confirmed that the dual inhibition of these complexes activates the PINK1-Parkin pathway. Intriguingly, we discovered that albumin, specifically bovine serum albumin (BSA) and human serum albumin (HSA) commonly present in culture media, can hinder carbonyl cyanide m-chlorophenyl hydrazone (CCCP)-induced pathway activation. However, cloflucarban's efficacy remains unaffected by albumin, highlighting its reliability for studying the PINK1-Parkin pathway. This study provides insights into the activation of the upstream PINK1-Parkin pathway and underscores the influence of culture conditions on research outcomes. Cloflucarban emerges as a promising tool for investigating mitochondrial quality control and neurodegenerative diseases.


Assuntos
Carbanilidas , Proteínas Quinases , Ubiquitina-Proteína Ligases , Humanos , Proteínas Quinases/metabolismo , Reprodutibilidade dos Testes , Ubiquitina-Proteína Ligases/metabolismo , Mitocôndrias/metabolismo , Albuminas/metabolismo
2.
Chimia (Aarau) ; 77(3): 154-158, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38047820

RESUMO

The Catalysis Hub - Swiss CAT+ is a new infrastructure project funded by ETH-domain, co-headed by EPFL and ETHZ. It offers the scientific community a unique integrated technology platform combining automated and high-throughput experimentation with advanced computational data analysis to accelerate the discoveries in the field of sustainable catalytic technologies. Divided into two hubs of expertise, homogeneous catalysis at EPFL and heterogeneous catalysis at ETHZ, the platform is open to academic and private research groups. Following a multi-year investment plan, both hubs have acquired and developed several high-end robotic platforms devoted to the synthesis, characterization, and testing of large numbers of molecular and solid catalysts. The hardware is associated with a fully digitalized experimental workflow and a specific data management strategy to support closed-loop experimentation and advanced computational data analysis.

3.
iScience ; 26(8): 107389, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37554439

RESUMO

Blue and green ammonia production have been proposed as low-carbon alternatives to emissions-intensive conventional ammonia production. Although much attention has been given to comparing these alternatives, it is still not clear which process has better environmental and economic performance. We present a techno-economic analysis and full life cycle assessment to compare the economics and environmental impacts of blue and green ammonia production. We address the importance of time horizon in climate change impact comparisons by employing the Technology Warming Potential, showing that methane leakage can exacerbate the climate change impacts of blue ammonia in short time horizons. We represent a constrained renewable electricity availability scenario by comparing the climate change impact mitigation efficiency per kWh of renewable electricity. Our work emphasizes the importance of maintaining low natural gas leakage for sustainability of blue ammonia, and the potential for technological advances to further reduce the environmental impacts of photovoltaics-based green ammonia.

4.
ChemSusChem ; 16(19): e202300608, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37313791

RESUMO

The CO2 -to-aromatics process is a chemical reaction that converts carbon dioxide (CO2 ) into valuable petrochemical, i. e., aromatics (especially, benzene, toluene, and xylene) over the metal/zeolite bifunctional catalytic systems. These aromatics are used in producing plastics, fibers, and other industrial products, which are currently exclusively sourced from fossil-derived feedstocks. The significance of this process lies in its potential to mitigate climate change by reducing greenhouse gas emissions and simultaneously producing valuable chemicals. Consequently, these CO2 -derived aromatics can reduce the reliance on fossil fuels as a source of feedstocks, which can help to promote a more sustainable and circular economy. Owing to the existence of a wider straight channel favoring the aromatization process, zeolite ZSM-5 is extensively used to yield aromatics during CO2 hydrogenation over bifunctional (metal/zeolite) catalytic systems. To provide a better understanding of this unique property of zeolite ZSM-5, this work investigates the impact of particle size and hierarchy of the zeolite and how these govern the reaction performance and the overall selectivity. As a result, an improved understanding of the zeolite-catalyzed hydrocarbon conversion process has been obtained.

5.
Surg Neurol Int ; 14: 145, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37151461

RESUMO

Background: Plasma cell neoplasms are characterized by the neoplastic proliferation of a single clone of plasma cells. Solitary plasmacytomas most often occur in bone, but they can also be found in soft tissues. Case Description: A 53-year-old male presented with localized sacral pain and urinary incontinence. His radiographic studies showed a solitary sacral plasmacytoma (i.e., involving the bone). He was successfully managed with high-dose dexamethasone and microwave ablation (MWA). Conclusion: Plasmacytomas of bone can be occasionally successfully managed with MWA, adjuvant cytoreduction therapy, and high doses of dexamethasone.

6.
ACS Appl Mater Interfaces ; 15(4): 5218-5228, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36688511

RESUMO

The valorization of CO2 to produce high-value chemicals, such as methanol and hydrocarbons, represents key technology in the future net-zero society. Herein, we report further investigation of a PdZn/ZrO2 + SAPO-34 catalyst for conversion of CO2 and H2 into propane, already presented in a previous work. The focus of this contribution is on the scale up of this catalyst. In particular, we explored the effect of mixing (1:1 mass ratio) and shaping the two catalyst functions into tablets and extrudates using an alumina binder. Their catalytic performance was correlated with structural and spectroscopic characteristics using methods such as FT-IR and X-ray absorption spectroscopy. The two scaled-up bifunctional catalysts demonstrated worse performance than a 1:1 mass physical mixture of the two individual components. Indeed, we demonstrated that the preparation negatively affects the element distribution. The physical mixture is featured by the presence of a PdZn alloy, as demonstrated by our previous work on this sample and high hydrocarbon selectivity among products. For both tablets and extrudates, the characterization showed Zn migration to produce Zn aluminates from the alumina binder phase upon reduction. Moreover, the extrudates showed a remarkable higher amount of Zn aluminates before the activation rather than the tablets. Comparing tablets and extrudates with the physical mixture, no PdZn alloy was observed after activation and only the extrudates showed the presence of metallic Pd. Due to the Zn migration, SAPO-34 poisoning and subsequent deactivation of the catalyst could not be excluded. These findings corroborated the catalytic results: Zn aluminate formation and Pd0 separation could be responsible for the decrease of the catalytic activity of the extrudates, featured by high methane selectivity and unconverted methanol, while tablets displayed reduced methanol conversion to hydrocarbons mainly attributed to the partial deactivation of the SAPO-34.

7.
Surg Neurol Int ; 13: 409, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36324923

RESUMO

Background: Angiolipomas are benign mesenchymal tumors that infrequently affect the head-and-neck region and can appear with infiltrating and non-infiltrating forms. Surgical excision is the treatment of choice; however, there are other alternatives to manage this condition whose consideration is quite useful to evaluate per each particular case. Case Description: An 11-year-old girl was diagnosed with non-infiltrating angiolipoma in the subtemporal region, the zygomatic, and pterygomaxillary fossa; she had a history of having undergone surgery on two previous occasions with a failed resection attempt due to the high vascularization of the injury and significant transoperative bleeding. The condition was managed with minimally invasive techniques through microwave ablation, requiring two sessions, achieving very satisfactory results both esthetically and in the final size of the lesion. Conclusion: The microwave ablation technique may turn out to be a very useful tool for the management of lesions with high vascularization such as angiolipoma. This technique offers a new possibility for initial management, both independent of and complementary to other management techniques for other lesions at the base of the skull and/or facial massif regions.

8.
ACS Appl Bio Mater ; 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35994395

RESUMO

Three fluorescent probes A, B, and C that function in the near-infrared wavelengths and utilize pseudo xanthene platforms with an oxygen atom at the 10-position replaced by a [Me-N]2- group have been created to identify hypoxia via nitroreductase determinations at the 0.04, 0.10, and 0.19 ng/mL levels. Theoretical calculations suggest that the probes are not planar due to steric interactions. Absorptions of photons result in the transition of electron density from the indoline moieties to delocalized orbitals on the anthranilic section, ending up on the nitro groups of the electron-poor (i.e., nonreduced) probes (i.e., A, B, and C), whereas those for the more electron-rich (i.e., reduced) probes consisted of movement from the indoline groups to the right side of the anthranilic sections, resulting in a shift in absorption.

9.
Chempluschem ; 87(6): e202200177, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35695481

RESUMO

In order to empower a circular carbon economy for addressing global CO2 emissions, the production of carbon-neutral fuels is especially desired, since addressing the global fuel demand via this route has the potential to significantly mitigate carbon emissions. In this study, we report a multifunctional catalyst combination consisting of a potassium promoted iron catalyst (Fe-K) and platinum containing zeolite beta (Pt-beta) which produces an almost entirely paraffinic mixture (up to C10 hydrocarbons) via CO2 hydrogenation in one step. Here, the Fe catalyst is responsible for modified Fischer-Tropsch synthesis from CO2 while Pt-beta is instrumental in tuning the product distribution almost entirely towards paraffins (both linear and branched) presumably via a combination of cracking and hydrogenation. The optimal temperature of operation was estimated to be 325 °C for the production of higher paraffins (C5 -C10 ) with a selectivity of ca. 28 % at a CO2 conversion of ca. 31 %.

10.
Mol Cell Proteomics ; 21(10): 100262, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35753663

RESUMO

The nonpsychoactive cannabinoid, cannabidiol (CBD), is Food and Dug Administration approved for treatment of two drug-resistant epileptic disorders and is seeing increased use among the general public, yet the mechanisms that underlie its therapeutic effects and side-effect profiles remain unclear. Here, we report a systems-level analysis of CBD action in human cell lines using temporal multiomic profiling. FRET-based biosensor screening revealed that CBD elicits a sharp rise in cytosolic calcium, and activation of AMP-activated protein kinase in human keratinocyte and neuroblastoma cell lines. CBD treatment leads to alterations in the abundance of metabolites, mRNA transcripts, and proteins associated with activation of cholesterol biosynthesis, transport, and storage. We found that CBD rapidly incorporates into cellular membranes, alters cholesterol accessibility, and disrupts cholesterol-dependent membrane properties. Sustained treatment with high concentrations of CBD induces apoptosis in a dose-dependent manner. CBD-induced apoptosis is rescued by inhibition of cholesterol synthesis and potentiated by compounds that disrupt cholesterol trafficking and storage. Our data point to a pharmacological interaction of CBD with cholesterol homeostasis pathways, with potential implications in its therapeutic use.


Assuntos
Canabidiol , Canabinoides , Humanos , Canabidiol/farmacologia , Cálcio/metabolismo , Proteínas Quinases Ativadas por AMP , Linhagem Celular , Canabinoides/farmacologia , Homeostase , RNA Mensageiro/metabolismo , Colesterol
11.
Nature ; 606(7915): 706-712, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35732759

RESUMO

To use natural gas as a feedstock alternative to coal and oil, its main constituent, methane, needs to be isolated with high purity1. In particular, nitrogen dilutes the heating value of natural gas and is, therefore, of prime importance for removal2. However, the inertness of nitrogen and its similarities to methane in terms of kinetic size, polarizability and boiling point pose particular challenges for the development of energy-efficient nitrogen-removing processes3. Here we report a mixed-linker metal-organic framework (MOF) membrane based on fumarate (fum) and mesaconate (mes) linkers, Zr-fum67-mes33-fcu-MOF, with a pore aperture shape specific for effective nitrogen removal from natural gas. The deliberate introduction of asymmetry in the parent trefoil-shaped pore aperture induces a shape irregularity, blocking the transport of tetrahedral methane while allowing linear nitrogen to permeate. Zr-fum67-mes33-fcu-MOF membranes exhibit record-high nitrogen/methane selectivity and nitrogen permeance under practical pressures up to 50 bar, removing both carbon dioxide and nitrogen from natural gas. Techno-economic analysis shows that our membranes offer the potential to reduce methane purification costs by about 66% for nitrogen rejection and about 73% for simultaneous removal of carbon dioxide and nitrogen, relative to cryogenic distillation and amine-based carbon dioxide capture.

12.
Nanoscale ; 14(19): 7332-7340, 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35535713

RESUMO

Ethylene oxide is one of the most important raw materials in the chemical industry, with an annual production close to 35 million metric tons. Despite its importance, to date, no metal has been found that can compete with the original silver bulk material catalyst discovered in 1931. Recently, a few copper and copper-silver based nanostructures have demonstrated remarkable selectivity and activity, especially when coupled with an industrial chlorine promoter. The present work evaluates the mechanistic role of chlorine as an active promoter of the selective oxidation of ethylene to ethylene oxide in the presence of a silver-copper oxide hybrid nanocatalyst (AgCuO). Experimental kinetic studies combined with density functional theory (DFT) calculations provide insight into the influence that Ag/CuO-supported chlorine atoms have over the ethylene epoxidation reaction. Remarkably, the typically described indirect route via the formation of an oxametallacycle (OMC) is also accompanied by a direct route. Furthermore, the presence of chlorine seems to facilitate a more favorable adsorption energy for ethylene oxide (EO) than for acetaldehyde (AA), the main reaction by-product. As a result, complete oxidation of EO can be further prevented in the presence of this AgCuO hybrid heteronanostructure.

13.
Methods Mol Biol ; 2488: 227-236, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35347692

RESUMO

Synthetic triterpenoids, 2-cyano-3,12-dioxooleana-1,9-dien-28-oic acid (CDDO) and its derivatives are known to have potent anti-cancer and anti-inflammatory activities. The mechanisms of actions of CDDO and its derivatives as potential therapeutics remain elusive. Previous studies found that CDDO-Me triggers apoptosis by inducing extracellular Ca2+ influx followed by endoplasmic reticulum (ER)-derived vacuolation. Since Ca2+ activity in cells is dynamic and needs to be tracked in real time in living cells, we report a high-throughput and high-content imaging method to track CDDO-induced Ca2+ fluctuation in both ER and cytosol with MATLAB script for data analysis and visualization.


Assuntos
Antineoplásicos , Ácido Oleanólico , Triterpenos , Antineoplásicos/farmacologia , Apoptose , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/farmacologia
15.
J Colloid Interface Sci ; 611: 739-751, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34876260

RESUMO

A dendritic PdCu/Ce0.3Zr0.7O2 (PdCu/CZ-3) catalyst with uniform spherical morphology was prepared for boosting the catalytic performance of CO2 hydrogenation to methanol (MeOH). The open dendritic pore channels and small particle sizes could reduce not only the diffuse resistance of reactants and products but also increase the accessibility between the active sites (PdCu and oxygen vacancy) and the reactants (H2 and CO2). More spillover hydrogen could be generated due to the highly dispersed PdCu active metals over the PdCu/CZ-3 catalyst. PdCu/CZ-3 can stimulate the generation of more Ce3+ cations, which is beneficial to produce more oxygen vacancies on the surface of the CZ-3 composite. Spillover hydrogen and oxygen vacancy could promote the formate and methoxy routes over PdCu/CZ-3, the primary intermediates producing MeOH. PdCu/CZ-3 displayed the highest CO2 conversions (25.5 %), highest MeOH yield (6.4 %), highest PdCu-TOFMeOH (7.7 h-1) and superior 100 h long-term stability than those of other PdCu/CexZr1-xO2 analogs and the reference PdCu/CeO2 and PdCu/ZrO2 catalysts. Density functional theory (DFT) calculations and in situ DRIFTS were performed to investigate the CO2 - MeOH hydrogenation mechanism.


Assuntos
Dióxido de Carbono , Metanol , Catálise , Hidrogenação , Oxigênio
16.
Eur J Cell Biol ; 101(1): 151185, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34915361

RESUMO

The PINK1/Parkin pathway plays an important role in maintaining a healthy pool of mitochondria. Activation of this pathway can lead to apoptosis, mitophagy, or mitochondrial-derived vesicle formation, depending on the nature of mitochondrial damage. The signaling by which PINK/Parkin activation leads to these different mitochondrial outcomes remains understudied. Here we present evidence that cannabidiol (CBD) activates the PINK1-Parkin pathway in a unique manner. CBD stimulates PINK1-dependent Parkin mitochondrial recruitment similarly to other well-studied Parkin activators but with a distinctive shift in the temporal dynamics and mitochondrial fates. The mitochondrial permeability transition pore inhibitor cyclosporine A exclusively diminished the CBD-induced PINK1/Parkin activation and its associated mitochondrial effects. Unexpectedly, CBD treatment also induced elevated production of mitochondrial-derived vesicles (MDV), a potential quality control mechanism that may help repair partial damaged mitochondria. Our results suggest that CBD may engage the PINK1-Parkin pathway to produce MDV and repair mitochondrial lesions via mitochondrial permeability transition pore opening. This work uncovered a novel link between CBD and PINK1/Parkin-dependent MDV production in mitochondrial health regulation.


Assuntos
Canabidiol , Mitofagia , Mitocôndrias , Proteínas Quinases , Ubiquitina-Proteína Ligases
17.
JACS Au ; 1(11): 1961-1974, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34841412

RESUMO

The production of carbon-neutral fuels from CO2 presents an avenue for causing an appreciable effect in terms of volume toward the mitigation of global carbon emissions. To that end, the production of isoparaffin-rich fuels is highly desirable. Here, we demonstrate the potential of a multifunctional catalyst combination, consisting of a methanol producer (InCo) and a Zn-modified zeolite beta, which produces a mostly isoparaffinic hydrocarbon mixture from CO2 (up to ∼85% isoparaffin selectivity among hydrocarbons) at a CO2 conversion of >15%. The catalyst combination was thoroughly characterized via an extensive complement of techniques. Specifically, operando X-ray absorption spectroscopy (XAS) reveals that Zn (which plays a crucial role of providing a hydrogenating function, improving the stability of the overall catalyst combination and isomerization performance) is likely present in the form of Zn6O6 clusters within the zeolite component, in contrast to previously reported estimations.

18.
JACS Au ; 1(10): 1719-1732, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34723275

RESUMO

The production of carbon-rich hydrocarbons via CO2 valorization is essential for the transition to renewable, non-fossil-fuel-based energy sources. However, most of the recent works in the state of the art are devoted to the formation of olefins and aromatics, ignoring the rest of the hydrocarbon commodities that, like propane, are essential to our economy. Hence, in this work, we have developed a highly active and selective PdZn/ZrO2+SAPO-34 multifunctional catalyst for the direct conversion of CO2 to propane. Our multifunctional system displays a total selectivity to propane higher than 50% (with 20% CO, 6% C1, 13% C2, 10% C4, and 1% C5) and a CO2 conversion close to 40% at 350 °C, 50 bar, and 1500 mL g-1 h-1. We attribute these results to the synergy between the intimately mixed PdZn/ZrO2 and SAPO-34 components that shifts the overall reaction equilibrium, boosting CO2 conversion and minimizing CO selectivity. Comparison to a PdZn/ZrO2+ZSM-5 system showed that propane selectivity is further boosted by the topology of SAPO-34. The presence of Pd in the catalyst drives paraffin production via hydrogenation, with more than 99.9% of the products being saturated hydrocarbons, offering very important advantages for the purification of the products.

19.
Nat Commun ; 12(1): 5914, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34625554

RESUMO

Cascade processes are gaining momentum in heterogeneous catalysis. The combination of several catalytic solids within one reactor has shown great promise for the one-step valorization of C1-feedstocks. The combination of metal-based catalysts and zeolites in the gas phase hydrogenation of CO2 leads to a large degree of product selectivity control, defined mainly by zeolites. However, a great deal of mechanistic understanding remains unclear: metal-based catalysts usually lead to complex product compositions that may result in unexpected zeolite reactivity. Here we present an in-depth multivariate analysis of the chemistry involved in eight different zeolite topologies when combined with a highly active Fe-based catalyst in the hydrogenation of CO2 to olefins, aromatics, and paraffins. Solid-state NMR spectroscopy and computational analysis demonstrate that the hybrid nature of the active zeolite catalyst and its preferred CO2-derived reaction intermediates (CO/ester/ketone/hydrocarbons, i.e., inorganic-organic supramolecular reactive centers), along with 10 MR-zeolite topology, act as descriptors governing the ultimate product selectivity.

20.
Nanomaterials (Basel) ; 11(3)2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33652611

RESUMO

The Lebedev process, in which ethanol is catalytically converted into 1,3-butadiene, is an alternative process for the production of this commodity chemical. Silica-magnesia (SiO2-MgO) is a benchmark catalyst for the Lebedev process. Among the different preparation methods, the SiO2-MgO catalysts prepared by wet-kneading typically perform best owing to the surface magnesium silicates formed during wet-kneading. Although the thermal treatment is of pivotal importance as a last step in the catalyst preparation, the effect of the calcination temperature of the wet-kneaded SiO2-MgO on the Lebedev process has not been clarified yet. Here, we prepared and characterized in detail a series of wet-kneaded SiO2-MgO catalysts using varying calcination temperatures. We find that the thermal treatment largely influences the type of magnesium silicates, which have different catalytic properties. Our results suggest that the structurally ill-defined amorphous magnesium silicates and lizardite are responsible for the production of ethylene. Further, we argue that forsterite, which has been conventionally considered detrimental for the formation of ethylene, favors the formation of butadiene, especially when combined with stevensite.

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