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1.
ChemSusChem ; : e202301683, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38696275

RESUMO

The development of multifunctional catalysts is a necessary step to effectively carry out one-pot cascade reactions, such as that from furfural to γ-valerolactone. This research effort faces the challenge posed by the intrinsic limit of how many kinds of catalytic sites a single material can bear. In this work, the application of Spray-Freeze Drying (SFD) as a synthetic technique for the preparation of a wide range of innovative composite multi-functional catalysts is reported. Herein we show that by the proper combination of Aquivion as a highly active Brønsted acid catalyst and metal oxides as both support materials and Lewis acids (LAS) enable to achieve highly unique efficient and effective dual acid composite catalysts that are able to carry out the cascade reaction from furfural to γ-valerolactone. The dual catalytic system comprised of Aq/ZrO2 with 30 % polymer content prepared via spray-freeze drying exhibited GVL yields of 25 % after only 2 h at 180 °C and a remarkably high productivity of 4470 µmolGVL gCat -1 h-1, one of the highest reported results. Mechanistic studies based on experimental and advanced characterisation and spectroscopic techniques, such as, SEM, TEM, 15N MAS NMR and 19F MAS NMR indicate that activity arises from the proper tuning of BAS/LAS (Brønsted Acid Site/Lewis Acid Site) acidic properties.

2.
Brain Pathol ; 32(5): e13074, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35478467

RESUMO

Several lines of evidence link deficient serotonin function and SUDEP. Chronic treatment with serotonin reuptake inhibitors (SRIs) reduces ictal central apnoea, a risk factor for SUDEP. Reduced medullary serotonergic neurones, modulators of respiration in response to hypercapnia, were reported in a SUDEP post-mortem series. The amygdala and hippocampus have high serotonergic innervation and are functionally implicated in seizure-related respiratory dysregulation. We explored serotonergic networks in mesial temporal lobe structures in a surgical and post-mortem epilepsy series in relation to SUDEP risk. We stratified 75 temporal lobe epilepsy patients with hippocampal sclerosis (TLE/HS) into high (N = 16), medium (N = 11) and low risk (N = 48) groups for SUDEP based on generalised seizure frequency. We also included the amygdala in 35 post-mortem cases, including SUDEP (N = 17), epilepsy controls (N = 10) and non-epilepsy controls (N = 8). The immunohistochemistry labelling index (LI) and axonal length (AL) of serotonin transporter (SERT)-positive axons were quantified in 13 regions of interest with image analysis. SERT LI was highest in amygdala and subiculum regions. In the surgical series, higher SERT LI was observed in high risk than low risk cases in the dentate gyrus, CA1 and subiculum (p < 0.05). In the post-mortem cases higher SERT LI and AL was observed in the basal and accessory basal nuclei of the amygdala and peri-amygdala cortex in SUDEP compared to epilepsy controls (p < 0.05). Patients on SRI showed higher SERT in the dentate gyrus (p < 0.005) and CA4 (p < 0.05) but there was no difference in patients with or without a psychiatric history. Higher SERT in hippocampal subfields in TLE/HS cases with SUDEP risk factors and higher amygdala SERT in post-mortem SUDEP cases than epilepsy controls supports a role for altered serotonergic networks involving limbic regions in SUDEP. This may be of functional relevance through reduced 5-HT availability.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Morte Súbita Inesperada na Epilepsia , Tonsila do Cerebelo , Epilepsia/patologia , Epilepsia do Lobo Temporal/patologia , Hipocampo/patologia , Humanos , Esclerose/patologia , Convulsões/patologia , Proteínas da Membrana Plasmática de Transporte de Serotonina , Lobo Temporal
3.
J Pers Med ; 11(6)2021 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-34071112

RESUMO

Music therapy (MT) is considered one of the complementary strategies to pharmacological treatment for behavioral and psychological symptoms (BPSD) of dementia. However, studies adopting MT protocols tailored for institutionalized people with dementia are limited and their usefulness for supporting caregivers is under investigated to date. Our study aimed at evaluating the effects of an MT intervention according to Gerdner and colleagues' protocol in a sample of 60 elderly people with moderate-to-severe dementia of the Auxologico Institute (Milan, Italy) and associated caregivers, randomly assigned to an Experimental Group (EG) (n = 30) undergoing 30 min of MT two times a week for 8 weeks and to a Control Group (n = 30) (CG) receiving standard care. Before and after the intervention, residents-associated caregivers were administered the Caregiver Burden Inventory (CBI) and the Neuropsychiatric Inventory (NPI). Depression and worry were also assessed in caregivers prior to the intervention, by the Beck Depression Inventory-II and the Penn State Worry Questionnaire, respectively. A mixed model ANCOVA revealed a Time*Group effect (p = 0.006) with regard to CBI decreasing after the intervention for the EG and Time*Group effects (p = 0.001) with regard to NPI_frequencyXseverity and NPI_distress, with a greater effect for the EG than the CG. Implications for MT protocols implementations are discussed.

4.
Inorg Chem ; 56(1): 645-653, 2017 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-28001385

RESUMO

We describe the functionalization of the layered perovskite HLaNb2O7 with n-propanol, n-decanol, 3-mercaptopropyl-trimethoxysilane, imidazole, n-decylamine, and histamine. The use of sonication is found to significantly improve the reaction yield and to reduce the reaction time, compared to conventional thermal treatment under reflux. The obtained intercalates are thoroughly characterized through the use of several complementary experimental techniques (scanning electron microscopy, IR spectroscopy, X-ray diffraction, thermogravimetric analysis, magic-angle spinning NMR), clarifying their structure and chemical bonding. The implications for the design of inorganic-organic composite materials are discussed.

5.
Phys Chem Chem Phys ; 18(31): 21903-12, 2016 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-27440133

RESUMO

Dion-Jacobson phases, like MLaNb2O7, are an interesting class of ion-exchangeable layered perovskites possessing electronic and photocatalytic properties. Their protonated and organo-modified homologues, in particular, have already been indicated as promising catalysts. However, the structural analysis of these highly tailorable materials is still incomplete, and both the intercalation process and thermal stability of the included organic moieties are far from being completely understood. In this study, we present a thorough solid-state NMR characterization of HLaNb2O7·xH2O intercalated with different amounts of octylamine, or with decylamine. Samples were analyzed as prepared, and after thermal treatment at different temperatures up to 220 °C. The substitution of pristine proton ions was followed via(1)H MAS NMR spectroscopy, whereas the alkyl chains were monitored through (13)C((1)H) CP MAS experiments. The interactions in the interlayer space were explored using (13)C((1)H) 2D heteronuclear correlation experiments. We demonstrate that some of the protons are involved in the functionalization reaction, and some of them are in close proximity to the alkyl ammonium chains. Heating of the hybrid materials leads first to a rearrangement of the alkyl chains and then to their degradation. The spatial arrangement of the chains, their interactions and the thermal behavior of the materials depend on the extent of the functionalization, and on the nature of the intercalated alkyl ammonium ions.

6.
Angew Chem Int Ed Engl ; 54(16): 4773-7, 2015 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-25689486

RESUMO

New mesoporous covalent frameworks, based on hybrid fluorinated organosilicas, were prepared to realize a periodic architecture of fast molecular rotors containing dynamic dipoles in their structure. The mobile elements, designed on the basis of fluorinated p-divinylbenzene moieties, were integrated into the robust covalent structure through siloxane bonds, and showed not only the rapid dynamics of the aromatic rings (ca. 10(8) Hz at 325 K), as detected by solid-state NMR spectroscopy, but also a dielectric response typical of a fast dipole reorientation under the stimuli of an applied electric field. Furthermore, the mesochannels are open and accessible to diffusing in gas molecules, and rotor mobility could be individually regulated by I2 vapors. The iodine enters the channels of the periodic structure and reacts with the pivotal double bonds of the divinyl-fluoro-phenylene rotors, affecting their motion and the dielectric properties.

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