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1.
Chemistry ; : e202400868, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38576402

RESUMO

Polymorphism-dependent cytotoxicity and cellular uptake of drug molecules have been studied for the past two decades. However, visualizing the polymorph-dependent cellular uptake and cytotoxicity using microscopy imaging technique has not been reported yet. The luminescent polymorph is an ideal candidate to validate the above hypothesis. Herein, we report the polymorph-dependent cellular uptake, cytotoxicity, and bio-imaging functions of polymorphs 1Y and 1R of a naphthalimide-phenothiazine dyad. These polymorphs show different luminescence colors in the solid state and exhibit aggregation-induced enhanced emission (AIEE) in the DMSO-Water mixture. Bioimaging, cytotoxicity assay, and fluorescence-activated cell sorting (FACS) studies revealed that these polymorphs show different levels of cytotoxicity, cellular uptake, localization, and imaging potential. Detailed photophysical, morphological, and biological studies revealed that the difference in molecular conformation in these polymorphs enables them to form aggregates of different sizes and morphology, which leads to the differential uptake of these into the cells and consequently shows different cytotoxicity and imaging potentials.

2.
J Pharm Biomed Anal ; 242: 116038, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38428367

RESUMO

In the pharmaceutical industry, the unexpected appearance of crystalline forms could impact the therapeutic efficacy of an Active Pharmaceutical Ingredient (API). For quality control, a thorough qualitative and quantitative monitoring of pharmaceutical solid forms is essential to ensure the detection and the quantification of crystalline forms, wither different or with the same chemical composition (polymorphs) at a low detection level. The purpose of this paper was to review and highlight the importance of choosing adequate solid-state techniques for detection and quantification APIs that present polymorphism - based on limits of detection (LOD) and quantification (LOQ), pharmacopeias specifications, international guidelines and studies reported in the literature. To this study, the powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), Infrared and Raman spectroscopies and solid-state nuclear magnetic resonance (NMR) were the solid-state techniques analyzed. Additionally, the Argentine, Brazilian, British, European, International, Japanese, Mexican and the United States of America pharmacopeias were reviewed. Based on the analysis performed, the advantages and disadvantages of these techniques, as well as the LOD and LOQ values of APIs were reported. In comparison to these solid-state techniques, reference material used for identification analyses should be previously identified with the corresponding polymorph. Without this previous procedure, the patterns, the spectra, and DSC curves of the reference material can only be used to confirm the mixture of solid forms, not being able to specify which polymorphs are contained in the sample. A major advantage of PXRD is the use of the calculated diffraction patterns obtained from the Crystallographic Information Frameworks (CIFs) files which could be used as a reference pattern without any other information, assistance technique, or physical standards. Regarding the quantification aspect, different pharmacopeias suggest various methods such as the PXRD combining with Rietveld method, which can be used to obtain lower LOD values for minority phases in the mixture of different substances without the need for a calibration curve. Raman spectroscopy can detect polymorphs in small particles and solid-state NMR spectroscopy is a powerful technique for quantification not only crystalline but also crystalline-amorphous mixtures. Finally, this review intends to be a useful tool to control, with efficiency and accuracy, the polymorphism of APIs in pharmaceutical compounds.


Assuntos
Indústria Farmacêutica , Limite de Detecção , Difração de Raios X , Preparações Farmacêuticas , Brasil , Varredura Diferencial de Calorimetria
3.
Acta Crystallogr C Struct Chem ; 80(Pt 4): 123-128, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38511904

RESUMO

A newly synthesized N,N'-dipropyl-substituted isoindigo derivative, namely, 1-propyl-3-(1-propyl-1,2-dihydro-2-oxo-3H-indol-3-ylidene)-1,3-dihydro-2H-indol-2-one, C22H22N2O2, was found to have three polymorphic forms (denoted Forms I, II and III) under various crystallization conditions. Crystal structure analysis indicated that Form III had a significantly different molecular conformation from the other two polymorphs. Their different packing arrangements were correlated with differences in the intermolecular interactions. Thermal measurements revealed that Forms I and II are enantiotropically related, and Form II exhibits thermally dynamic behaviour.

4.
Nano Lett ; 24(3): 966-974, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38206580

RESUMO

Two-dimensional (2D) Fe chalcogenides with their rich structures and properties are highly desirable for revealing the torturous transition mechanism of Fe chalcogenides and exploring their potential applications in spintronics and nanoelectronics. Hydrostatic pressure can effectively stimulate phase transitions between various ordered states, allowing one to successfully plot a phase diagram for a given material. Herein, the structural evolution and transport characteristics of 2D FeTe were systematically investigated under extreme conditions by comparing two distinct symmetries, i.e., tetragonal (t) and hexagonal (h) FeTe. We found that t-FeTe presented a pressure-induced transition from an antiferromagnetic state to a ferromagnetic state at ∼3 GPa, corresponding to the tetragonal collapse of the layered structure. Contrarily, the ferromagnetic order of h-FeTe was retained up to 15 GPa, which was evidently confirmed by electrical transport and Raman measurements. Furthermore, T-P phase diagrams for t-FeTe and h-FeTe were mapped under delicate critical conditions. Our results can provide a unique platform to elaborate the extraordinary properties of Fe chalcogenides and further develop their applications.

5.
J Inorg Biochem ; 250: 112420, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37918185

RESUMO

Two copper(I) polymorphs of formula [Cu(SALH)(TPP)3] (1a and 1b) were prepared by the conjugation of the Non-Steroidal Anti-Inflammatory Drug (NSAID) salicylic acid (SALH2) with the mitochondriotropic agent triphenylphosphine (TPP) via metal ion. For comparison, the isomorph [Ag(SALH)(TPP)3] (2) was prepared. The conjugates 1a, 1b and 2 were characterized by melting point (m.p.), Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy, Ultraviolet-Visible (UV-Vis) spectroscopy and nuclear magnetic resonance (1H NMR). The crystal structures of 1a, 1b and 2 were confirmed by X-ray diffraction crystallography (XRD). The ex vivo binding affinity of 1-2 towards CT (calf thymus)-DNA was studied by UV, fluorescence, viscosity and DNA Thermal Denaturation studies. Their inhibitory activity against lipoxygenase (LOX) (an enzyme which is mainly located in the mitochondrion) was determined. The in vitro activity of 1-2 was evaluated against human breast cancer cell lines MCF-7 (hormone depended (HD)) and MDA-MB 281 (hormone independent (HI)) cells. Compounds 1-2 inhibit stronger than cisplatin the cancerous cells. The molecular mechanism of action of 1-2 was suspected by the MCF-7 cells morphology and confirmed by DNA fragmentation, Acridine Orange/Ethidium Bromide (AO/EB) Staining and mitochondrial membrane permeabilization tests.


Assuntos
Antineoplásicos , Neoplasias da Mama , Complexos de Coordenação , Humanos , Feminino , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/química , Neoplasias da Mama/tratamento farmacológico , Prata/química , DNA/química , Hormônios , Antineoplásicos/farmacologia , Antineoplásicos/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Cobre
6.
Acta Pharmaceutica Sinica ; (12): 76-83, 2024.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1005439

RESUMO

Most chemical medicines have polymorphs. The difference of medicine polymorphs in physicochemical properties directly affects the stability, efficacy, and safety of solid medicine products. Polymorphs is incomparably important to pharmaceutical chemistry, manufacturing, and control. Meantime polymorphs is a key factor for the quality of high-end drug and formulations. Polymorph prediction technology can effectively guide screening of trial experiments, and reduce the risk of missing stable crystal form in the traditional experiment. Polymorph prediction technology was firstly based on theoretical calculations such as quantum mechanics and computational chemistry, and then was developed by the key technology of machine learning using the artificial intelligence. Nowadays, the popular trend is to combine the advantages of theoretical calculation and machine learning to jointly predict crystal structure. Recently, predicting medicine polymorphs has still been a challenging problem. It is expected to learn from and integrate existing technologies to predict medicine polymorphs more accurately and efficiently.

7.
Prog Neurobiol ; 232: 102562, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38135105

RESUMO

The misfolding and aggregation of the tau protein into neurofibrillary tangles constitutes a central feature of tauopathies. Traumatic brain injury (TBI) has emerged as a potential risk factor, triggering the onset and progression of tauopathies. Our previous research revealed distinct polymorphisms in soluble tau oligomers originating from single versus repetitive mild TBIs. However, the mechanisms orchestrating the dissemination of TBI brain-derived tau polymorphs (TBI-BDTPs) remain elusive. In this study, we explored whether TBI-BDTPs could initiate pathological tau formation, leading to distinct pathogenic trajectories. Wild-type mice were exposed to TBI-BDTPs from sham, single-blast (SB), or repeated-blast (RB) conditions, and their memory function was assessed through behavioral assays at 2- and 8-month post-injection. Our findings revealed that RB-BDTPs induced cognitive and motor deficits, concurrently fostering the emergence of toxic tau aggregates within the injected hippocampus. Strikingly, this tau pathology propagated to cortical layers, intensifying over time. Importantly, RB-BDTP-exposed animals displayed heightened glial cell activation, NLRP3 inflammasome formation, and increased TBI biomarkers, particularly triggering the aggregation of S100B, which is indicative of a neuroinflammatory response. Collectively, our results shed light on the intricate mechanisms underlying TBI-BDTP-induced tau pathology and its association with neuroinflammatory processes. This investigation enhances our understanding of tauopathies and their interplay with neurodegenerative and inflammatory pathways following traumatic brain injury.


Assuntos
Lesões Encefálicas Traumáticas , Tauopatias , Camundongos , Animais , Proteínas tau/metabolismo , Lesões Encefálicas Traumáticas/complicações , Tauopatias/metabolismo , Emaranhados Neurofibrilares/metabolismo , Inflamação/complicações , Modelos Animais de Doenças
8.
BBA Adv ; 4: 100110, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38053641

RESUMO

Synucleinopathies like Parkinson's disease are neurodegenerative diseases which are associated with the deposition of fibrillar aggregates of the endogenous protein α-synuclein (α-syn). The inhibition of the elongation of α-syn fibrils is of great scientific interest and an option in the design of therapeutic strategies. Previously, we developed a disulfide-containing mutant of α-syn, called CC48, which inhibits fibril elongation by blocking of fibril ends. Surprisingly, wildtype (WT) α-syn molecules supported the blocked state, and a fusion of CC48 with WT α-syn, denoted WT-CC48, exhibited increased inhibitory potential. Here, we studied which regions of WT-CC48 are responsible for the strong inhibitory effect. To this end, we investigated a set of truncated versions of WT-CC48 by kinetic elongation assays, density gradient centrifugation, and atomic force microscopy. We show that in both the WT and the CC48 part of the fusion construct the hairpin region (residue 32-60) and NAC region (61-95), but not N- and C-terminal regions, are required for strong inhibition of fibril elongation. The required regions correspond to the segments forming the ß-sheet core of α-syn fibrils. As α-syn fibrils typically consist of two protofilaments, the dimeric construct WT-CC48 provides the critical regions sufficient to cover the full ß-sheetcore interface exposed at the fibril end, which can explain its high inhibitory efficiency. We suggest a mechanistic model of CC48-mediated inhibition of fibril elongation in which CC48 and WT α-syn cooperatively form an oligomer-like cap at the amyloid fibril end.

9.
Small ; : e2309961, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38098343

RESUMO

Different phases of Ga2 O3 have been regarded as superior platforms for making new-generation high-performance electronic devices. However, understanding of thermal transport in different phases of nanoscale Ga2 O3 thin-films remains challenging, owing to the lack of phonon transport models and systematic experimental investigations. Here, thermal conductivity (TC) and thermal boundary conductance (TBC) of the ( 1 ¯ 010 ) $( {\bar 1010} )$ α-, ( 2 ¯ 01 ) $( {\bar 201} )\;$ ß-, and (001) κ-Ga2 O3 thin films on sapphire are investigated. At ≈80 nm, the measured TC of α (8.8 W m-1 K-1 ) is ≈1.8 times and ≈3.0 times larger than that of ß and κ, respectively, consistent with model based on density functional theory (DFT), whereas the model reveals a similar TC for the bulk α- and ß-Ga2 O3 . The observed phase- and size-dependence of TC is discussed thoroughly with phonon transport properties such as phonon mean free path and group velocity. The measured TBC at Ga2 O3 /sapphire interface is analyzed with diffuse mismatch model using DFT-derived full phonon dispersion relation. Phonon spectral distribution of density of states, transmission coefficients, and group velocity are studied to understand the phase-dependence of TBC. This study provides insight into the fundamental phonon transport mechanism in Ga2 O3 thin films and paves the way for improved thermal management of high-power Ga2 O3 -based devices.

10.
IUCrJ ; 10(Pt 6): 766-771, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37910142

RESUMO

Phosphorus exists in several different allotropes: white, red, violet and black. For industrial and academic applications, white phosphorus is the most important. So far, three polymorphs of white phosphorus, all consisting of P4 tetrahedra, have been described. Among these, ß-P4 crystallizes in the space group P1 and γ-P4 in the space group C2/m. α-P4 forms soft plastic crystals with a proposed structure in the cubic space group I43m with the lattice constant a = 18.51 (3) Å, consisting of 58 rotationally disordered tetrahedra and thus is similar to the structure of α-Mn. Here we present a new polymorph, δ-P4. It crystallizes as a sixfold twin with the cell dimensions a = 18.302 (2), b = 18.302 (2), c = 36.441 (3) Šin the space group P212121 with 29 P4 tetrahedra in the asymmetric unit. The arrangement resembles the structure of α-Mn, but δ-P4 differs from α-P4. DFT calculations show δ-P4 to be metastable at a similar energy level to that of γ-P4.

11.
Cell Mol Life Sci ; 80(12): 376, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38010414

RESUMO

Apolipoproteins co-deposit with amyloids, yet apolipoprotein-amyloid interactions are enigmatic. To understand how apoE interacts with Alzheimer's amyloid-ß (Aß) peptide in fibrillary deposits, the NMR structure of full-length human apoE was docked to four structures of patient-derived Aß1-40 and Aß1-42 fibrils determined previously using cryo-electron microscopy or solid-state NMR. Similar docking was done using the NMR structure of human apoC-III. In all complexes, conformational changes in apolipoproteins were required to expose large hydrophobic faces of their amphipathic α-helices for sub-stoichiometric binding to hydrophobic surfaces on sides or ends of fibrils. Basic residues flanking the hydrophobic helical faces in apolipoproteins interacted favorably with acidic residue ladders in some amyloid polymorphs. Molecular dynamics simulations of selected apoE-fibril complexes confirmed their stability. Amyloid binding via cryptic sites, which became available upon opening of flexibly linked apolipoprotein α-helices, resembled apolipoprotein-lipid binding. This mechanism probably extends to other apolipoprotein-amyloid interactions. Apolipoprotein binding alongside fibrils could interfere with fibril fragmentation and secondary nucleation, while binding at the fibril ends could halt amyloid elongation and dissolution in a polymorph-specific manner. The proposed mechanism is supported by extensive prior experimental evidence and helps reconcile disparate reports on apoE's role in Aß aggregation. Furthermore, apoE domain opening and direct interaction of Arg/Cys158 with amyloid potentially contributes to isoform-specific effects in Alzheimer's disease. In summary, current modeling supported by prior experimental studies suggests similar mechanisms for apolipoprotein-amyloid and apolipoprotein-lipid interactions; explains why apolipoproteins co-deposit with amyloids; and helps reconcile conflicting reports on the chaperone-like apoE action in Aß aggregation.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Apolipoproteínas E , Humanos , Doença de Alzheimer/metabolismo , Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Apolipoproteínas/química , Apolipoproteínas/metabolismo , Apolipoproteínas E/metabolismo , Encéfalo/metabolismo , Microscopia Crioeletrônica , Simulação de Dinâmica Molecular , Fragmentos de Peptídeos/metabolismo
12.
Int J Pharm ; 648: 123573, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37931725

RESUMO

Ball milling is used, not only to reduce the particle size of pharmaceutical powders, but also to induce changes in the physical properties of drugs. In this work we prepared three crystal forms of furosemide (forms Ⅰ, Ⅱ, and Ⅲ) and studied their solid phase transformations during ball milling. Powder X-ray diffraction and modulated differential scanning calorimetry were used to characterize the samples after each milling time on their path to amorphization. Our results show that forms Ⅰ and III directly converted into an amorphous phase, while form Ⅱ first undergoes a polymorphic transition to form Ⅰ, and then gradually loses its crystallinity, finally reaching full amorphousness. During ball milling of forms Ⅰ and Ⅱ, the glass transition temperature (Tg) of the amorphous fraction of the milled material remains almost unchanged at 75 °C and 74 °C, respectively (whilst the amorphous content increases). In contrast, the Tg values of the amorphous fraction of milled form III increase with increasing milling times, from 63 °C to 71 °C, indicating an unexpected phenomenon of amorphous-to-amorphous transformation. The amorphous fraction of milled forms I and II samples presented a longer structural relaxation (i.e., lower molecular mobility) than the amorphous fraction of milled form III samples. Moreover, the structural relaxation time remained the same for the increasing amorphous fraction during milling of forms I and II. In contrast, the structural relaxation times were always shorter for the amorphous fraction of form III, but increased with increasing amorphous content during milling, confirming amorphous-to-amorphous transformation.


Assuntos
Furosemida , Cristalização/métodos , Temperatura , Temperatura de Transição , Difração de Raios X , Varredura Diferencial de Calorimetria , Estabilidade de Medicamentos
13.
Pharmaceutics ; 15(8)2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37631378

RESUMO

Surfactants have been widely used as effective additives to increase the solubility and dissolution rates of amorphous solid dispersions (ASDs). However, they may also generate adverse effects on the physical stability of ASDs. In this study, we systematically investigated the impacts of poloxamer, a frequently used surfactant, on the crystallization of amorphous clotrimazole (CMZ). The added poloxamer significantly decreased the glass transition temperature (Tg) of CMZ and accelerated the growth of Form 1 and Form 2 crystals. It was found that the poloxamer had an accelerating effect on Form 1 and Form 2 but showed a larger accelerating effect on Form 1, which resulted from a combined effect of increased mobility and local phase separation at the crystal-liquid interface. Additionally, the added poloxamer exhibited different effects on nucleation of the CMZ polymorphs, which was more complicated than crystal growth. The nucleation rate of Form 1 was significantly increased by the added poloxamer, and the effect increased with increasing P407 content. However, for Form 2, nucleation was slightly decreased or unchanged. The nucleation of Form 2 may have been influenced by the Form 1 crystallization, and Form 2 converted to Form 1 during nucleation. This study increases our understanding of poloxamer and its impacts on the melt crystallization of drugs.

14.
bioRxiv ; 2023 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-37577501

RESUMO

Apolipoproteins co-deposit with amyloids, yet apolipoprotein-amyloid interactions are enigmatic. To understand how apoE interacts with Alzheimer's amyloid-ß (Aß) peptide in fibrillary deposits, the NMR structure of full-length human apoE was docked to four structures of patient-derived Aß1-40 and Aß1-42 fibrils determined previously using cryo-electron microscopy or solid-state NMR. Similar docking was done using the NMR structure of human apoC-III. In all complexes, conformational changes in apolipoproteins were required to expose large hydrophobic faces of their amphipathic α-helices for sub-stoichiometric binding to hydrophobic surfaces on sides or ends of fibrils. Basic residues flanking the hydrophobic helical faces in apolipoproteins interacted favorably with acidic residue ladders in some amyloid polymorphs. Molecular dynamics simulations of selected apoE-fibril complexes confirmed their stability. Amyloid binding via cryptic sites, which became available upon opening of flexibly linked apolipoprotein α-helices, resembled apolipoprotein-lipid binding. This mechanism probably extends to other apolipoprotein-amyloid interactions. Apolipoprotein binding alongside fibrils could interfere with fibril fragmentation and secondary nucleation, while binding at the fibril ends could halt amyloid elongation and dissolution in a polymorph-specific manner. The proposed mechanism is supported by extensive prior experimental evidence and helps reconcile disparate reports on apoE's role in Aß aggregation. Furthermore, apoE domain opening and direct interaction of Arg/Cys158 with amyloid potentially contributes to isoform-specific effects in Alzheimer's disease. In summary, current modeling supported by prior experimental studies suggests similar mechanisms for apolipoprotein-amyloid and apolipoprotein-lipid interactions; explains why apolipoproteins co-deposit with amyloids; and helps reconcile conflicting reports on the chaperone-like apoE action in Aß aggregation.

15.
Molecules ; 28(16)2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-37630390

RESUMO

Guanine crystals with unique optical properties in organisms have been extensively studied and the biomineralization principles of guanine are being established. This review summarizes the fundamental physicochemical properties (solubility, tautomers, bands, and refractivity), polymorphs, morphology of biological and synthetic forms, and the reported biomineralization principles of guanine (selective recrystallization of amorphous precursor, preassembled scaffolds, additives, twinning, hypoxanthine doping, fluorescence, and assembly). The biomineralization principles of guanine will be helpful for the synthesis of guanine crystals with excellent properties and the design of functional organic materials for drugs, dyes, organic semiconductors, etc.

16.
ACS Appl Mater Interfaces ; 15(33): 39956-39965, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37552034

RESUMO

Quantifying the crystallographic phases present at a surface is an important challenge in fields such as functional materials and surface science. X-ray photoelectron spectroscopy (XPS) is routinely employed in surface characterization to identify and quantify chemical species through core line analysis. Valence band (VB) spectra contain characteristic but complex features that provide information on the electronic density of states (DoS) and thus can be understood theoretically using density functional theory (DFT). Here, we present a method of fitting experimental photoemission spectra with DFT models for quantitative analysis of heterogeneous systems, specifically mapping the anatase to rutile ratio across the surface of mixed-phase TiO2 thin films. The results were correlated with mapped photocatalytic activity measured using a resazurin-based smart ink. This method allows large-scale functional and surface composition mapping in heterogeneous systems and demonstrates the unique insights gained from DFT-simulated spectra on the electronic structure origins of complex VB spectral features.

17.
Chemistry ; 29(61): e202301942, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37486717

RESUMO

A silica zeolite (RWZ-1) with a very high framework density (FD) was synthesized from highly crystalline natural layered silicate magadiite, bridging the gap between the two research areas of zeolites and dense silica polymorphs. Magadiite was topotactically converted into a 3D framework through two-step heat treatment. The resulting structure had a 1D micropore system of channel-like cavities with an FD of 22.1 Si atoms/1000 Å3 . This value is higher than those of all other silica zeolites reported so far, approaching those of silica polymorphs (tridymite (22.6) and α-quartz (26.5)). RWZ-1 is a slight negative thermal expansion material with thermal properties approaching those of dense silica polymorphs. It contributes to the creation of a new field on microporous high-density silica/silicates. Synergistic interactions are expected between the micropores with molecular sieving properties and the dense layer-like building units with different topologies which provide thermal and mechanical stabilities.

18.
Curr Protein Pept Sci ; 24(6): 503-517, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37282635

RESUMO

Trehalose, a disaccharide molecule of natural origin, is known for its diverse biological applications, like in drug development, research application, natural scaffold, stem cell preservation, food, and various other industries. This review has discussed one such diverse molecule 'trehalose aka mycose', and its diverse biological applications with respect to therapeutics. Due to its inertness and higher stability at variable temperatures, it has been developed as a preservative to store stem cells, and later, it has been found to have anticancer properties. Trehalose has recently been associated with modulating cancer cell metabolism, diverse molecular processes, neuroprotective effect, and so on. This article describes the development of trehalose as a cryoprotectant and protein stabilizer as well as a dietary component and therapeutic agent against various diseases. The article discusses its role in diseases via modulation of autophagy, various anticancer pathways, metabolism, inflammation, aging and oxidative stress, cancer metastasis and apoptosis, thus highlighting its diverse biological potential.


Assuntos
Estresse Oxidativo , Trealose , Trealose/farmacologia , Trealose/metabolismo , Células-Tronco/metabolismo , Autofagia
19.
Adv Mater ; 35(42): e2302756, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37364565

RESUMO

The assembly of supramolecular structures within living systems is an innovative approach for introducing artificial constructs and developing biomaterials capable of influencing and/or regulating the biological responses of living organisms. By integrating chemical, photophysical, morphological, and structural characterizations, it is shown that the cell-driven assembly of 2,6-diphenyl-3,5-dimethyl-dithieno[3,2-b:2',3'-d]thiophene-4,4-dioxide (DTTO) molecules into fibers results in the formation of a "biologically assisted" polymorphic form, hence the term bio-polymorph. Indeed, X-ray diffraction reveals that cell-grown DTTO fibers present a unique molecular packing leading to specific morphological, optical, and electrical properties. Monitoring the process of fiber formation in cells with time-resolved photoluminescence, it is established that cellular machinery is necessary for fiber production and a non-classical nucleation mechanism for their growth is postulated. These biomaterials may have disruptive applications in the stimulation and sense of living cells, but more crucially, the study of their genesis and properties broadens the understanding of life beyond the native components of cells.


Assuntos
Materiais Biocompatíveis , Difração de Raios X
20.
Nanomaterials (Basel) ; 13(9)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37177057

RESUMO

Reversible insulator-metal transition (IMT) and structure phase change in vanadium dioxide (VO2) remain vital and challenging with complex polymorphs. It is always essential to understand the polymorphs that coexist in desired VO2 materials and their IMT behaviors. Different electrical properties and lattice alignments in VO2 (M) and VO2 (B) phases have enabled the creation of versatile functional devices. Here, we present polymorphous VO2 thin films with coexistent VO2 (M) and VO2 (B) phases and phase-dependent IMT behaviors. The presence of VO2 (B) phases may induce lattice distortions in VO2 (M). The plane spacing of (011)M in the VO2 (M) phase becomes widened, and the V-V and V-O vibrations shift when more VO2 (B) phase exists in the VO2 (M) matrix. Significantly, the coexisting VO2 (B) phases promote the IMT temperature of the polymorphous VO2 thin films. We expect that such coexistent polymorphs and IMT variations would help us to understand the microstructures and IMT in the desired VO2 materials and contribute to advanced electronic transistors and optoelectronic devices.

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