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1.
Membranes (Basel) ; 12(12)2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36557090

RESUMO

We provide a high resolution, all-atom, femto-second molecular dynamics (MD) simulation of the passage of K+ ions and H2O molecules through the selectivity filter of the KcsA potassium ion channel, based on first principle physical methods. Our results show that a change in the length of the selectivity filter of as little as 3%, regardless of whether the filter is made longer or shorter, will reduce the K+ ion current by around 50%. In addition, further squeezing or stretching by about 9% can effectively stop the current. Our results demonstrate optimized conformational dynamics that associate an increased mobility of parts in the filter linings with a standard configuration, leading to maximized conduction rates that are highly sensitive to geometrical distortions. We discuss this latter aspect in relation to lateral membrane effects on the filter region of ion channels and the 'force from lipids' hypothesis.

2.
Molecules ; 27(16)2022 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-36014412

RESUMO

Substitution of the chlorido ligand of cyclometalated [Pt (5-R-1,3-di(2-pyridyl) benzene)Cl] (R = methyl, mesityl, 2-thienyl, or 4-diphenylamino-phenyl) by 4-phenylthiazole-2-thiolate leads to related thiolato complexes, which were fully characterized. Their photophysical properties were determined in degassed dichloromethane solution. The emission color of the novel complexes can be easily tuned by the nature of the substituents on the terdentate ligand, as is the case for the parent chlorido complexes. Their luminescence Quantum Yield is high, with that of the compounds with the 2-thienyl or 4-diphenylamino-phenyl substituents being much higher than that of the related chloride complexes. The platinum complex with the cyclometalated 5-(2-thienyl)-1,3-di(2-pyridyl) benzene was used as the emitter for the fabrication of a yellow solution-processable OLED.

3.
Dalton Trans ; 51(32): 12161-12169, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35876615

RESUMO

The preparation and characterization of three new complexes, namely [Pt(1,3-bis(4-triphenylamine-pyridin-2-yl)-4,6-difluoro-benzene)Cl] ([PtL1Cl]), [Pt(1,3-bis(4-triphenylamine-pyridin-2-yl)-5-triphenylamine-benzene)Cl] ([PtL2Cl]), and [Pt(1,3-bis(4-triphenylamine-pyridin-2-yl)-5-mesityl-benzene)Cl] ([PtL3Cl]), is reported. All of them are highly luminescent in dilute deaerated dichloromethane solution (Φlum = 0.88-0.90, in the yellow-green region; the λmax,em in nm for the monomers are: 562, 561 and 549 for [PtL1Cl], [PtL2Cl] and [PtL3Cl], respectively).[PtL1Cl] is the most appealing, being characterized by a very long lifetime (103.9 µs) and displaying intense NIR emission in concentrated deaerated solution (Φlum = 0.66) with essentially no "contamination" by visible light < 600 nm. This complex allows the fabrication of both yellow-green and deep red/NIR OLEDs; OLED emissions are in the yellow-green (CIE = 0.38, 0.56) and deep red/NIR (CIE = 0.65, 0,34) regions, for [PtL1Cl] 8 wt% (with 11% ph/e EQE) and pure [PtL1Cl] (with 4.3% ph/e EQE), respectively.

4.
Sci Rep ; 12(1): 9861, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35701600

RESUMO

Green electronics is an emerging topic that requires the exploration of new methodologies for the integration of green components into electronic devices. Therefore, the development of alternative and eco-friendly raw materials, biocompatible and biodegradable, is of great importance. Among these, sodium-alginate is a natural biopolymer extracted from marine algae having a great potential in terms of transparency, flexibility, and conductivity, when functionalized with a thin gold (Au) layer. The electrical transport of these flexible and conducting substrates has been studied, by DC measurements, from 300 to 10 K, to understand the interplay between the organic substrate and the metallic layer. The results were compared to reference bilayers based on polymethyl-methacrylate, a well-known polymer used in electronics. In addition, a detailed investigation of the electric noise properties was also performed. This analysis allows to study the effect of charge carriers fluctuations, providing important information to quantify the minimum metallic thickness required for electronic applications. In particular, the typical noise behavior of metallic compounds was observed in samples covered with 5 nm of Au, while noise levels related to a non-metallic conduction were found for a thickness of 4.5 nm, despite of the relatively good DC conductance of the bilayer.


Assuntos
Alginatos , Ouro , Eletrônica , Ouro/química , Sódio , Análise Espectral
5.
Int J Mol Sci ; 23(9)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35563268

RESUMO

This Special Issue included articles discussing several important psychiatric phenomena whose elucidation can be provided by cellular and subcellular molecular mechanisms [...].

6.
Int J Mol Sci ; 23(6)2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35328673

RESUMO

Multiple Sclerosis is a chronic neurological disease characterized by demyelination and axonal loss. This pathology, still largely of unknown etiology, carries within it a complex series of etiopathogenetic components of which it is difficult to trace the origin. An inflammatory state is likely to be the basis of the pathology. Crucial elements of the inflammatory process are the interactions between platelets and mast cells as well as the bacterial component of the intestinal microbiota. In addition, the involvement of mast cells in autoimmune demyelinating diseases has been shown. The present work tries to hang up on that Ariadne's thread which, in the molecular complexity of the interactions between mast cells, platelets, microbiota and inflammation, characterizes Multiple Sclerosis and attempts to bring the pathology back to the causal determinism of psychopathological phenomenology. Therefore, we consider the possibility that the original error of Multiple Sclerosis can be investigated in the genetic origin of the depressive pathology.


Assuntos
Microbioma Gastrointestinal , Esclerose Múltipla , Plaquetas/patologia , Humanos , Inflamação , Mastócitos , Transtornos do Humor , Esclerose Múltipla/patologia , Células-Tronco/patologia
7.
Nat Prod Res ; 35(2): 331-336, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31170811

RESUMO

The grape pomace (GP) is an important by-product of winemaking, accounting for about 13-25% of the grapes processed. The aim of this work was to investigate the nutritional and antioxidant composition of GP obtained from Nero d'Avola (NA) grape, one of the most important indigenous varieties in Italy, in order to verify application in nutraceutics. Seeds and skin of the GP were studied for their nutritional and antioxidants composition, fatty acid and polyphenols profile, bioactives properties in vitro, by gravimetric, spectrophotometric and chromatographic techniques. The results showed that NAGP seeds are rich in the beneficial polyunsaturated fatty acids and that the polyphenols extracted from the GP skin present a strong antiradical and antiproliferative activity, attested also in vitro, in human skin fibroblast (HS-68) and in hepatoma cell line (Hep-G2). Obtained results underline the possibility to employ this residual biomass for nutraceuticals application, contributing also to increase the sustainability.


Assuntos
Biotecnologia/métodos , Suplementos Nutricionais , Sementes/química , Vitis/química , Antioxidantes/análise , Antioxidantes/química , Biomassa , Proliferação de Células/efeitos dos fármacos , Ácidos Graxos/análise , Células Hep G2 , Humanos , Itália , Polifenóis/análise , Polifenóis/farmacologia
9.
Behav Brain Sci ; 42: e28, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30940246

RESUMO

Autism spectrum disorder (ASD) subjects can present temporary behaviors of acute agitation and aggressiveness, named problem behaviors. They have been shown to be consistent with the self-organized criticality (SOC), a model wherein occasionally occurring "catastrophic events" are necessary in order to maintain a self-organized "critical equilibrium." The SOC can represent the psychopathology network structures and additionally suggests that they can be considered as self-organized systems.


Assuntos
Transtorno do Espectro Autista , Encefalopatias , Comportamento Problema , Humanos , Psicopatologia , Pesquisa
10.
Eur J Nutr ; 58(5): 2145-2156, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30076458

RESUMO

PURPOSE: Gut dysbiosis has been described in advanced, but not in initial stages of CKD. Considering the relevant impact of gut dysbiosis on renal and cardiovascular risk, its diagnosis and treatment are clinically relevant. METHODS: We designed, open-label, placebo-controlled intervention study (ProbiotiCKD) to evaluate gut microbiota metabolism in a cohort of KDIGO CKD patients (n = 28) at baseline and after a randomly assigned treatment with probiotics or placebo. Gut microbiota status was evaluated on:. RESULTS: Basal mean fecal Lactobacillales and Bifidobacteria concentrations were abnormally low in both groups, while urinary indican and 3-MI levels were, indicating a mixed (fermentative and putrefactive) dysbiosis. After treatment, mean fecal Lactobacillales and Bifidobacteria concentrations were increased, only in the probiotics group (p < 0.001). Conversely, mean urinary indican and 3-MI levels only in the group treated with probiotics (p < 0.001). Compared to placebo group, significant improvements of C-reactive protein (p < 0.001), iron (p < 0.001), ferritin (p < 0.001), transferrin saturation (p < 0.001), ß2-microglobulin (p < 0.001), serum iPTH and serum calcium were observed only in the probiotics group. CONCLUSIONS: ProbiotiCKD is the first intervention study demonstrating that an intestinal mixed dysbiosis is present even in early CKD stage and can be effectively corrected by the novel mode of administration of high-quality probiotics with improvement of inflammatory indices, iron status and iPTH stabilization.


Assuntos
Protocolos Clínicos , Disbiose/tratamento farmacológico , Microbioma Gastrointestinal/efeitos dos fármacos , Probióticos/uso terapêutico , Insuficiência Renal/tratamento farmacológico , Insuficiência Renal/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
11.
Open Vet J ; 9(3): 253-258, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31998619

RESUMO

Mammalian gastrointestinal tract is colonized by a large number of microorganisms, known as gut microbiota, that play a key role in the physiological and pathological states. In particular, the gastrointestinal tract of dogs and cats harbors a complex and highly biodiverse microbial ecosystem. Recent studies see it involved in a wide range of life processes, including energy needs, metabolism, immunological activity, and neuro-behavioral development. This review focuses on the role of the microbiota on the health of pets and will discuss changes that occur in the disease.


Assuntos
Doenças do Gato/microbiologia , Doenças do Cão/microbiologia , Microbioma Gastrointestinal , Animais , Gatos , Cães
13.
J Am Chem Soc ; 140(6): 2336-2347, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29298047

RESUMO

A series of copper(I) pseudorotaxanes has been prepared from bis[2-(diphenylphosphino)phenyl] ether (POP) and macrocyclic phenanthroline ligands with different ring sizes (m30, m37, and m42). Variable-temperature studies carried out on the resulting [Cu(mXX)(POP)]+ (mXX = m30, m37, and m42) derivatives have revealed a dynamic conformational equilibrium due to the folding of the macrocyclic ligand. The absorption and luminescence properties of the pseudorotaxanes have been investigated in CH2Cl2. They exhibit metal-to-ligand charge-transfer emission with photoluminescence quantum yields (PLQYs) in the range 20-30%. The smallest system [Cu(m30)(POP)]+ shows minimal differences in spectral shape and position compared to its analogues, suggesting a slightly distorted coordination environment. PLQY is substantially enhanced in poly(methyl methacrylate) films (∼40-45%). The study of emission spectra and excited-state lifetimes in powder samples as a function of temperature (78-338 K) reveals thermally activated delayed fluorescence, with sizable differences in the singlet-triplet energy gap compared to the reference compound [Cu(dmp)(POP)]+ (dmp = 2,9-dimethyl-1,10-phenanthroline) and within the pseudorotaxane series. The system with the largest ring ([Cu(m42)(POP)]+) has been tested as emissive material in OLEDs and affords bright green devices with higher luminance and greater stability compared to [Cu(dmp)(POP)]+, which lacks the macrocyclic ring. This highlights the importance of structural factors in the stability of electroluminescent devices based on Cu(I) materials.

14.
J Integr Neurosci ; 17(2): 177-183, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28922165

RESUMO

Living organisms tend to find viable strategies under ambient conditions that optimize their search for, and utilization of, life-sustaining resources. For plants, a leading role in this process is performed by auxin, a plant hormone that drives morphological development, dynamics, and movement to optimize the absorption of light (through branches and leaves) and chemical "food" (through roots). Similarly to auxin in plants, serotonin seems to play an important role in higher animals, especially humans. Here, it is proposed that morphological and functional similarities between (i) plant leaves and the animal/human brain and (ii) plant roots and the animal/human gastro-intestinal tract have general features in common. Plants interact with light and use it for biological energy, whereas, neurons in the central nervous system seem to interact with biophotons and use them for proper brain function. Further, as auxin drives the "arborescence" of roots within the soil, similarly serotonin seems to facilitate enteric nervous system connectivity within the human gastrointestinal tract. This auxin/serotonin parallel suggests the root-branch axis in plants may be an evolutionary precursor to the gastrointestinal-brain axis in humans. Finally, it is hypothesized that light might be an important factor, both in gastrointestinal dynamics and brain function. Such a comparison may indicate a key role for the interaction of light and serotonin in neuronal physiology (possibly in both the central nervous system and the enteric nervous system), and according to recent work, mind and consciousness.


Assuntos
Encéfalo/metabolismo , Microbioma Gastrointestinal , Modelos Teóricos , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Evolução Biológica , Estado de Consciência/fisiologia , Humanos , Ácidos Indolacéticos/metabolismo , Luz , Neurônios/metabolismo , Teoria Quântica , Serotonina/metabolismo
15.
J Integr Neurosci ; 16(s1): S13-S18, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29125495

RESUMO

In this paper, we present some diverse points of view on the issue of the quantum brain.The paper is structured in the form of opening statements by each of the co-authors followed by comments and critique presented by the other co-authors. The main focus of the discussion is on the interplay between the state of being alive and consciousness, both of which possess characteristics of quantum physical states.


Assuntos
Encéfalo/fisiologia , Encéfalo/fisiopatologia , Estado de Consciência/fisiologia , Modelos Neurológicos , Inconsciência/fisiopatologia , Humanos , Teoria Quântica
17.
J Integr Neurosci ; 16(s1): S1-S2, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29103044
18.
Inorg Chem ; 56(15): 8975-8985, 2017 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-28696105

RESUMO

The reaction of the ß-triketonate ligands tris(4-methylbenzoyl)methanide and tribenzoylmethanide with the trivalent lanthanoids Eu3+, Er3+, and Yb3+ in the presence of Cs+ afforded polymeric structures where the repeating units are represented by bimetallic tetranuclear assemblies of formulation {[Ln(Cs)(ß-triketonate)4]2}n. The only exception is the structure formed by the reaction of tris(4-methylbenzoyl)methanide, Yb3+, and Cs+, which yielded a polymeric assembly where the repeating units are mononuclear Yb3+ complexes bridged by Cs+ cations. Photophysical measurements on the obtained materials confirmed efficient sensitization from the ligand excited states to the 4f* excited states of the three lanthanoids. According to transient absorption data, Er3+ and Yb3+ are sensitized via energy transfer from the triplet state of the ß-triketonate ligands. On the other hand, energy transfer to Eu3+ seems to occur via an alternative pathway, possibly directly via the singlet state or through ligand to metal charge transfer states. The emission measurements confirm efficient sensitization for all three lanthanoids and bright near-infrared emission for Er3+ and Yb3+, a characteristic that seems to be linked to the specific chemical structure of the ß-triketonate ligands.

19.
BMC Neurosci ; 18(1): 38, 2017 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-28420346

RESUMO

In this paper we present a mechanistic model that integrates subneuronal structures, namely ion channels, membrane fatty acids, lipid rafts, G proteins and the cytoskeleton in a dynamic system that is finely tuned in a healthy brain. We also argue that subtle changes in the composition of the membrane's fatty acids may lead to down-stream effects causing dysregulation of the membrane, cytoskeleton and their interface. Such exquisite sensitivity to minor changes is known to occur in physical systems undergoing phase transitions, the simplest and most studied of them is the so-called Ising model, which exhibits a phase transition at a finite temperature between an ordered and disordered state in 2- or 3-dimensional space. We propose this model in the context of neuronal dynamics and further hypothesize that it may involve quantum degrees of freedom dependent upon variation in membrane domains associated with ion channels or microtubules. Finally, we provide a link between these physical characteristics of the dynamical mechanism to psychiatric disorders such as major depression and antidepressant action.


Assuntos
Encéfalo , Ácido Linoleico/metabolismo , Modelos Neurológicos , Transtornos do Humor/metabolismo
20.
Med Hypotheses ; 101: 78-84, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28351500

RESUMO

The accepted paradigms of mainstream neuropsychiatry appear to be incompletely adequate and in various cases offer equivocal analyses. However, a growing number of new approaches are being proposed that suggest the emergence of paradigm shifts in this area. In particular, quantum theories of mind, brain and consciousness seem to offer a profound change to the current approaches. Unfortunately these quantum paradigms harbor at least two serious problems. First, they are simply models, theories, and assumptions, with no convincing experiments supporting their claims. Second, they deviate from contemporary mainstream views of psychiatric illness and do so in revolutionary ways. We suggest a possible way to integrate experimental neuroscience with quantum models in order to address outstanding issues in psychopathology. A key role is played by the phenomenon called the "stream of consciousness", which can be linked to the so-called "Gamma Synchrony" (GS), which is clearly demonstrated by EEG data. In our novel proposal, a unipolar depressed patient could be seen as a subject with an altered stream of consciousness. In particular, some clues suggest that depression is linked to an "increased power" stream of consciousness. It is additionally suggested that such an approach to depression might be extended to psychopathology in general with potential benefits to diagnostics and therapeutics in neuropsychiatry.


Assuntos
Encéfalo/fisiopatologia , Estado de Consciência , Transtorno Depressivo/fisiopatologia , Psicopatologia/métodos , Membrana Celular/metabolismo , Citoesqueleto/metabolismo , Eletroencefalografia , Humanos , Microtúbulos , Neurônios/metabolismo , Neurociências , Teoria Quântica
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