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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120310, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34474222

RESUMO

A multimode responsive hypochlorite probe 1, based on Terbium (III)-1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (Tb(III)-DO3A) and 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY), is described. We have shown that probe 1 can detect ClO- by absorption, fluorescence, and phosphorescence simultaneously. The multimode response makes probe 1 a versatile ClO- probe for practical applications. We have found that probe 1 can be used in naked-eye colorimetric and fluorogenic detection of NaOCl in solution. Also, we have constructed a colorimetric test paper for visual sensing of NaOCl. Furthermore, fluorescence imaging studies indicated that probe 1 was a versatile tool for in vitro imaging of NaOCl in living cells. Thus, to the best of our knowledge, probe 1 represents one of the rare examples of multimode responsive ClO- probes.


Assuntos
Corantes Fluorescentes , Ácido Hipocloroso , Compostos de Boro , Espectrometria de Fluorescência
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 265: 120393, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34597923

RESUMO

In this article, we present synthesis, spectral characteristics, and results of DFT calculations of new CH(R)-bis(BODIPY) 1-3. They are characterized by the conformational mobility and sensitivity of fluorescence to polarity, proton-, electron donor ability and viscosity of the solvation environment. It is shown that fluorescence intensity of 1-3 increases in the homologous series of alcohols (ethanol, 1-propanol, 1-butanol, 1-octanol, 1-decanol) mainly due to decrease of medium acidic properties. The viscosity of the medium effects on the 1-3 fluorescence in a lesser degree. Compared to 1 and 2, the 3 is the most sensitive towards viscosity both in low-viscosity homologous alcohols and in high-viscosity ethanol-glycerol mixtures. In this regard, the sensitivity of fluorescence of CH(MeOPh)-bis(BODIPY) (compound 3) to the viscosity was studied in binary mixtures of polar DMF and low-polarity toluene with castor and vaseline oils, as well as to the macroviscosity of the solvate environment in mixtures of toluene with polystyrene. Prospects of the practical application of CH(R)-bis(BODIPY)s are proposed for the analysis of polarity, proton-donor properties and viscosity of the medium.


Assuntos
Compostos de Boro , Corantes Fluorescentes , Microscopia de Fluorescência , Viscosidade
3.
Biol Trace Elem Res ; 200(1): 134-146, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33634364

RESUMO

Boron has an important potential for facilitating biological activity and for use in pharmaceutical drug design. Boron glycine monoester (BGM) and boron glycine diester (BGD) compounds containing boron atoms were synthesized and investigated their cytotoxic, oxidative stress, and antimicrobial activities on the HepG2 cancer cell line. The cytotoxic activity of newly synthesized boron compounds on hepatocellular carcinoma was determined by the MTT method for 48 h. Antioxidant (CAT, GSH), lipid peroxidation (MDA), and enzyme activity (ACP, ALP) analyses were determined by spectrophotometric methods in HepG2 cells. Antimicrobial activity was determined by the disk diffusion method. After 48 h of BGM and BGD application to HepG2 cells, we found the IC50 values as 9.9 mM and 24 mM, respectively. While CAT and ACP enzyme activities decreased in all groups compared to the control, ALP enzyme activity did not change in the BGM group but increased in the BGD group. It was determined that the GSH level did not change in all groups, while the MDA level increased. It has been stated that these IC50 doses of BGM and BGD have antibacterial effects on Staphylococcus aureus ATCC 29213 and Escherichia coli ATCC 25922. Newly synthesized boron compounds, particularly BGM, with their cytotoxic, oxidative stress, and antimicrobial effects, could provide a new therapeutic approach for the treatment of hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Antioxidantes , Boro/farmacologia , Compostos de Boro/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Glicina , Humanos , Neoplasias Hepáticas/tratamento farmacológico
4.
J Nanosci Nanotechnol ; 21(6): 3283-3290, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34739783

RESUMO

Hybrid nanofluids, a new class of nanofluid has the ability to further enhance the thermo-physical properties by balancing the benefits of both kinds of nanomaterials as compared with nanofluids synthesized using only one kind of material. In this work, water-based nanofluids containing suspensions of carbon black (CB)-boron nitride (BN) (mass ratio = 50:50) nanoparticles are synthesized and studied for its rheological properties. The viscosity of CB-BN nanofluids are measured at temperatures between 30 °C-60 °C for volume concentrations 0.25 to 2 vol.%. The viscosity shows an increase with increasing particle concentration and decreases with temperature. A non-Newtonian nature with a dilatant behavior in the shear rate range of 5.4 s-1 to 130 s-1 is observed for all concentrations and temperatures. Also, it follows a power law model and its parameters, i.e., power index and consistency index are obtained by the curve fitting method. The non-Newtonian nature intensifies at low temperatures and concentrations. A new correlation is developed to predict the viscosity of CB-BN hybrid nanofluids.


Assuntos
Nanoestruturas , Fuligem , Compostos de Boro , Reologia , Viscosidade
5.
Nano Lett ; 21(19): 8182-8189, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34606291

RESUMO

Two-dimensional hexagonal boron nitride (hBN) that hosts room-temperature single-photon emitters (SPEs) is promising for quantum information applications. An important step toward the practical application of hBN is the on-demand, position-controlled generation of SPEs. Strategies reported for deterministic creation of hBN SPEs either rely on substrate nanopatterning that is not compatible with integrated photonics or utilize radiation sources that might introduce unpredictable damage or contamination to hBN. Here, we report a radiation- and lithography-free route to deterministically activate hBN SPEs by nanoindentation with atomic force microscopy (AFM). The method applies to hBN flakes on flat silicon dioxide-silicon substrates that can be readily integrated into on-chip photonic devices. The achieved SPE yields are above 30% for multiple indent sizes, and a maximum yield of 36% is demonstrated for indents around 400 nm. Our results mark an important step toward the deterministic creation and integration of hBN SPEs with photonic and plasmonic devices.


Assuntos
Compostos de Boro , Dióxido de Silício
6.
Phys Rev Lett ; 127(13): 138103, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34623840

RESUMO

Nanopores in 2D materials are highly desirable for DNA sequencing, yet achieving single-stranded DNA (ssDNA) transport through them is challenging. Using density functional theory calculations and molecular dynamics simulations we show that ssDNA transport through a pore in monolayer hexagonal boron nitride (h-BN) is marked by a basic nanomechanical conflict. It arises from the notably inhomogeneous flexural rigidity of ssDNA and causes high friction via transient DNA desorption costs exacerbated by solvation effects. For a similarly sized pore in bilayer h-BN, its self-passivated atomically smooth edge enables continuous ssDNA transport. Our findings shed light on the fundamental physics of biopolymer transport through pores in 2D materials.


Assuntos
Compostos de Boro/química , DNA de Cadeia Simples/química , Nanoestruturas/química , Fenômenos Biofísicos , Modelos Químicos , Simulação de Dinâmica Molecular , Nanoporos
7.
Nat Commun ; 12(1): 5956, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34642311

RESUMO

Photoredox catalysis is a powerful means to generate odd-electron species under mild reaction conditions from a wide array of radical precursors. Herein, we present the application of this powerful catalytic manifold to address the hydroalkylation and hydroaminoalkylation of electronically diverse vinylarenes. This reaction allows for generalized alkene hydroalkylation leveraging common alkyl radical precursors, such as organotrifluoroborate salts and carboxylic acids. Furthermore, utilizing easily accessible α-silyl amine reagents or tertiary amines directly, secondary and tertiary amine moieties can be installed onto monoaryl and diaryl alkenes to access valuable products, including γ,γ-diarylamines pharmacophores. Thus, under a unified system, both hydroalkylation and hydroaminoalkylation of alkenes are achieved. The substrate scope is evaluated through 57 examples, the synthetic utility of the method is demonstrated, and preliminary mechanistic insights are presented.


Assuntos
Aminas/síntese química , Compostos de Boro/química , Ácidos Carboxílicos/química , Elétrons , Compostos Macrocíclicos/síntese química , Compostos de Vinila/química , Alquilação , Catálise , Técnicas de Química Sintética/métodos , Humanos , Oxirredução , Processos Fotoquímicos
8.
J Phys Chem B ; 125(42): 11617-11627, 2021 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-34661408

RESUMO

Halogenated and alkylated BODIPY derivatives are reported as suitable candidates for their use as photosensitizers in photodynamic therapy due to their efficient intersystem crossing (ISC) between states of different spin multiplicities. Spin-orbit couplings (SOCs) are evaluated using an effective one-electron spin-orbit Hamiltonian for brominated and alkylated BODIPY derivatives to investigate the quantitative effect of alkyl and bromine substituents on ISC. BODIPY derivatives containing bromine atoms have been found to have significantly stronger SOCs than alkylated BODIPY derivatives outside the Frank-Condon region while they are nearly the same at local minima. Based on calculated time-dependent density functional theory (TD-DFT) vertical excitation energies and SOCs, excited-state dynamics of three BODIPY derivatives were further explored with TD-DFT surface hopping molecular dynamics employing a simple accelerated approach. Derivatives containing bromine atoms have been found to have very similar lifetimes, which are much shorter than those of the derivatives possessing just the alkyl moieties. However, both bromine atoms and alkyl moieties reduce the HOMO/LUMO gap, thus assisting the derivatives to behave as efficient photosensitizers.


Assuntos
Halogenação , Fármacos Fotossensibilizantes , Alquilação , Compostos de Boro
9.
J Phys Chem B ; 125(40): 11159-11178, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34605235

RESUMO

The aggregation of amyloid ß (Aß) peptide triggered by its conformational changes leads to the commonly known neurodegenerative disease of Alzheimer's. It is believed that the formation of ß sheets of the peptide plays a key role in its aggregation and subsequent fibrillization. In the current study, we have investigated the interactions of the Aß(1-42) peptide with boron nitride nanoparticles and the effects of the latter on conformational transitions of the peptide through a series of molecular dynamics simulations. In particular, the effects of curvature of the nanoparticle surface are studied by considering boron nitride nanotubes (BNNTs) of varying diameter and also a planar boron nitride nanosheet (BNNS). Altogether, the current study involves the generation and analysis of 9.5 µs of dynamical trajectories of peptide-BNNT/BNNS pairs in an aqueous medium. It is found that BN nanoparticles of different curvatures that are studied in the present work inhibit the conformational transition of the peptide to its ß-sheet form. However, such an inhibition effect follows different pathways for BN nanoparticles of different curvatures. For the BNNT with the highest surface curvature, i.e., (3,3) BNNT, the nanoparticle is found to inhibit ß-sheet formation by stabilizing the helical structure of the peptide, whereas for planar BNNS, the ß-sheet formation is prevented by making more favorable pathways available for transitions of the peptide to conformations of random coils and turns. The BNNTs with intermediate curvatures are found to exhibit diverse pathways of their interactions with the peptide, but in all cases, essentially no formation of the ß sheet is found whereas substantial ß-sheet formation is observed for Aß(1-42) in water in the absence of any nanoparticle. The current study shows that BN nanoparticles have the potential to act as effective tools to prevent amyloid formation from Aß peptides.


Assuntos
Nanopartículas , Doenças Neurodegenerativas , Peptídeos beta-Amiloides , Compostos de Boro , Humanos , Fragmentos de Peptídeos , Conformação Proteica em Folha beta , Água
10.
Mater Sci Eng C Mater Biol Appl ; 130: 112426, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34702511

RESUMO

In the case of dental pulp exposure, direct pulp capping is often performed to preserve vital dental pulp tissue. Numerous studies regarding the development of direct pulp-capping materials have been conducted, but materials with an appropriate sealing ability, which induce dense reparative dentin formation, have not been developed. Although nano hydroxyapatite (naHAp) is a bone-filling material with bioactivity and biocompatibility, the inductive effects of naHAp on reparative dentin formation remain unclear. In the present study, the effects of dental adhesive material 4-methacryloxyethyl trimellitate anhydride/methyl methacrylate tri-n-butylborane [4-META/MMA-TBB or Super-bond (SB)], which included 10%, 30%, and 50% naHAp (naHAp/SB) on odontoblastic differentiation of dental pulp stem cells (DPSCs) and reparative dentin formation were investigated. Scanning electron microscopy (SEM) and energy dispersive X-ray spectrometer analysis were performed to verify the existence of naHAp particles on the surface of naHAp/SB discs. The tensile adhesive strength of naHAp/SB was measured using a universal testing machine. As a result, 10% naHAp/SB and 30% naHAp/SB showed almost the same tensile adhesive strength as SB but 50% naHAp/SB showed significantly lower than the other experimental group. WST-1 proliferation assay and SEM analysis revealed that naHAp/SB did not affect the proliferation of DPSCs. Calcium release assay, quantitative RT-PCR, and western blotting analysis demonstrated that naHAp/SB did not release calcium ion but 30% naHAp/SB increased the expression of calcium-sensing receptor (CaSR) in DPSCs. Additionally, quantitative RT-PCR, western blotting analysis, Alizarin Red S- and von Kossa staining revealed that 30% naHAp/SB induced odontoblastic differentiation of DPSCs, which was inhibited by a MEK/ERK inhibitor and CaSR antagonist. Furthermore, 30% naHAp/SB promoted dense reparative dentin formation in an experimentally-formed rat dental pulp exposure model. These findings suggest that 30% naHAp/SB can be used as an ideal direct pulp capping material.


Assuntos
Durapatita , Cimentos de Resina , Animais , Compostos de Boro , Polpa Dentária , Metacrilatos , Metilmetacrilatos , Ratos
11.
Molecules ; 26(19)2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34641589

RESUMO

Pristine high-density bulk disks of MgB2 with added hexagonal BN (10 wt.%) were prepared using spark plasma sintering. The BN-added samples are machinable by chipping them into desired geometries. Complex shapes of different sizes can also be obtained by the 3D printing of polylactic acid filaments embedded with MgB2 powder particles (10 wt.%). Our present work aims to assess antimicrobial activity quantified as viable cells (CFU/mL) vs. time of sintered and 3D-printed materials. In vitro antimicrobial tests were performed against the bacterial strains Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 25923, Enterococcus faecium DSM 13590, and Enterococcus faecalis ATCC 29212; and the yeast strain Candida parapsilosis ATCC 22019. The antimicrobial effects were found to depend on the tested samples and microbes, with E. faecium being the most resistant and E. coli the most susceptible.


Assuntos
Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Compostos de Boro/farmacologia , Fungos/efeitos dos fármacos , Compostos de Magnésio/farmacologia , Candida parapsilosis/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecium/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Poliésteres/farmacologia , Impressão Tridimensional , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
12.
Molecules ; 26(19)2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34641615

RESUMO

Pathogenic E. coli infection is one of the most widespread foodborne diseases, so the development of sensitive, reliable and easy operating detection tests is a key issue for food safety. Identifying bacteria with a fluorescent medium is more sensitive and faster than using chromogenic media. This study designed and synthesized a ß-galactosidase-activatable fluorescent probe BOD-Gal for the sensitive detection of E. coli. It employed a biocompatible and photostable 4,4-difluoro-3a,4a-diaza-s-indancene (BODIPY) as the fluorophore to form a ß-O-glycosidic bond with galactose, allowing the BOD-Gal to show significant on-off fluorescent signals for in vitro and in vivo bacterial detection. This work shows the potential for the use of a BODIPY based enzyme substrate for pathogen detection.


Assuntos
Compostos de Boro/química , Escherichia coli/isolamento & purificação , Corantes Fluorescentes/química , Galactose/metabolismo , alfa-Galactosidase/metabolismo , Técnicas Biossensoriais , Ativação Enzimática , Escherichia coli/enzimologia , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Microbiologia de Alimentos , Galactose/química , Sensibilidade e Especificidade , alfa-Galactosidase/química
13.
Mikrobiyol Bul ; 55(4): 592-602, 2021 Oct.
Artigo em Turco | MEDLINE | ID: mdl-34666658

RESUMO

The pathogenic Cryptococcus neoformans causes life-threatening disease in immunocompromised patients. Although there are hypotheses about the role of lipid droplets in C.neoformans pathogenesis, there is still not extensively data determined on the subject yet. Lipid droplets are dynamic cytoplasmic energy storage bodies in yeasts. Diazo dyes, Nile red, LD540 and borradiazaindasen (BODIPY) molecules are frequently used in the lipid droplets studies. BODIPY (4,4-difluoro-4-bora-3a,4a-diaza-s-indacene) dyestuffs are among the brightest green light emitting fluorophores. These neutral molecules have high lipophilicity and can easily pass through the cell wall and membrane. In this study, for the future studies on lipid droplets of C.neoformans, we aimed to optimize three different BODIPY (BODIPY480/525, BODIPY480/530, BODIPY480/535) molecules for fluorescence microscopy and flow cytometry system. Ten molecularly confirmed environmental C.neoformans strains were grown on Sabouraud dextrose agar with and without oleic acid. BODIPY staining protocols at different concentrations were used for C.neoformans lipid droplets fixed with paraformaldehyde. The visualization (by fluorescence microscopy) and detection (by flow cytometer) of the lipid droplet structures of C.neoformans strains were evaluated. Forwardscatter and side-scatter analysis were performed to evaluate the number of lipid droplets determined in the cytoplasmic region quadrant in flow cytometry. The staining of the lipid droplets of C.neoformans of all three BODIPY molecules used in the study was observed by fluorescence microscope with creating distinct brightness and sharp contrast with the background. All BODIPY molecules could be examined by fluorescence microscopy without loss of brightness in more than one minute. The optimal dye concentration of BODIPY compounds were found as 2 µM. Incubation at room temperature for five minutes was sufficient for fluorochrome staining. They were also shown to be able to stain lipid droplets in heatinactivated C.neoformans strains in all three compounds. The synthesized BODIPY480/525, BODIPY480/530 and BODIPY480/535 molecules were evaluated in accordance with the staining of lipid droplets, which were claimed to play a role in the pathogenesis of C.neoformans, and analysis by fluorescence microscopy and analysis with flow cytometer. BODIPY molecules may exhibit different properties in staining lipid droplets. These molecules should be tested for demonstrating the presence of lipid droplets in different yeast species and their suitability for pathogenesis studies.


Assuntos
Cryptococcus neoformans , Compostos de Boro , Citometria de Fluxo , Corantes Fluorescentes , Humanos , Gotículas Lipídicas , Coloração e Rotulagem
14.
Biomater Sci ; 9(22): 7648-7654, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34676837

RESUMO

Bacterial infectious diseases and antimicrobial resistance seriously endanger human health, so alternative therapies for bacterial infections are urgently needed. Recently, photodynamic therapy against bacteria has shown great potential because of its high efficiency and low acquired resistance. Here, we design and synthesize a dipyrromethene boron difluoride (BODIPY) photosensitizer containing a guanidine group LIBDP for combating bacterial infections. The positively charged guanidine can destroy the bacterial membrane and inhibit the proliferation of bacteria to a certain extent. Upon light irradiation, LIBDP can produce reactive oxygen species (ROS), which can destroy the pre-formed biofilm and induce potent antibacterial activity. In addition, the guanidine of LIBDP can be oxidized to nitric oxide (NO) by the generated ROS, which can not only improve the antibacterial effect, but also promote wound healing. The strategy in this work paves the way for synthesizing high-performance antibacterial materials.


Assuntos
Bactérias Gram-Positivas , Fotoquimioterapia , Antibacterianos/farmacologia , Compostos de Boro , Humanos , Fármacos Fotossensibilizantes/uso terapêutico , Cicatrização
15.
J Mol Graph Model ; 109: 108041, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34653765

RESUMO

Loading of the Doxorubicin (DOX) as an anticancer drug molecule on boron nitride (BN) nanosheets with different sizes, in the presence and absence of Folic Acid (FA) functional groups, are investigated using molecular dynamic simulations. The obtained results from these investigations revealed that the drug molecules are spontaneously adsorbed the carriers and form stable complexes. It is also shown that an increase the nanosheet leads to an enhancement in its capacity to adsorb the drugs. Furthermore, the conjugation of BN with the FA group not only improves the BN efficiency for the drug adsorption but also helps the drug-carrier complex to target the cancerous cells. Evaluation of interaction energies reveals that L-J interaction plays an essential role in the adsorption of the drug molecules on the BN. The radial distribution function (RDF) shows that the highest drug position probability is around 0.6 nm away from the BN surface. Atomic RDF analysis is in line with the interaction energy analysis and proved that π-π stacking contributes the most to this process. Hydrogen bond (HB) analysis also shows that, although limited, the columbic interaction can be helpful in the adsorption process. Moreover, the free energy (FE) surface is explored for a system containing a BN nanosheet, an FA group, and a DOX molecule through metadynamics simulations. The obtained results reveal that the lowest FE point located in coordinations d1 = 0.70 nm and d2 = 0.84 nm, and energetically reached -280.42 kJ/mol. It can be concluded from the FE calculations that while the FA is stuck on the substrate, DOX faces difficulty in the way it be adsorbed. In return, it will be hard for the molecule to be released from the BN surface through desorption processes in neutral pH because it faces an energy barrier with a height of ∼100 kJ/mol at 1.6 nm.


Assuntos
Antineoplásicos , Ácido Fólico , Compostos de Boro , Doxorrubicina/farmacologia
16.
Bratisl Lek Listy ; 122(10): 753-758, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34570579

RESUMO

BACKGROUND: Seven dioxaborole compounds are investigated in this study. Structural and spectral characterization is done at M062X/6-31+G(d,p) level in the water. Active sites of these compounds are determined using molecular electrostatic potential (MEP) maps. Electrophilic and nucleophilic attack regions are determined. AIM: We aimed to determine whether Boron-Containing Compounds (BCCs) inhibitor used in the treatment of COVID-19 are effective against SARS Cov-2 in silico. RESULTS AND CONCLUSION: Since SARS-CoV-2 is a worldwide health problem, anti-viral properties of studied boron-containing compounds were investigated by molecular docking calculations. In addition to these calculations, MM/PSBA calculations were performed. It was found that boron compounds can be good drug candidate against SARS-CoV-2 and the best compound is ((R)-1-((S)-3-(4-(aminomethyl)phenyl)-2-benzamidopropanamido)-4-guanidinobutyl)boronic acid (C26) (Tab. 2, Fig. 6, Ref. 29). Text in PDF www.elis.sk Keywords: boronate ester, dioxaborole, in silico, SARS-CoV-2, MD calculations.


Assuntos
COVID-19 , SARS-CoV-2 , Antivirais/farmacologia , Antivirais/uso terapêutico , Compostos de Boro/farmacologia , Humanos , Simulação de Acoplamento Molecular
17.
Analyst ; 146(19): 5873-5879, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34487127

RESUMO

Two new ß-diketone-boron difluoride based near-infrared fluorescent probes 1 and 2 which exhibit polarity sensitivity have been designed and synthesized. Probes 1 and 2 are composed of a ß-diketone-boron difluoride moiety as an acceptor unit, and a diethylamino group and a phenolic hydroxyl group as donor units. The long conjugate structures form a "donor-acceptor-donor" configuration, induce intramolecular charge transfer (ICT), and confer near-infrared fluorescence emission and excellent polarity sensitivity. The photophysical properties of these two probes were investigated in detail. Experimental data demonstrated that as the environmental polarity decreased, the fluorescence intensity of the probes increased obviously, accompanied by a blue-shift of the maximum emission wavelength. In addition, these two probes were photostable and solely sensitive to polarity without interference from viscosity, pH and common active species. Theoretical calculations indicated that probes 1 and 2 displayed lower energy gaps and faster non-radiative decay in polar solvents. Furthermore, probes 1 and 2 were utilized to quantitatively detect the polarity of a binary mixture through the satisfactory linear relationship between the fluorescence emission intensity ratios and the orientation polarizability of the mixed solvent. Additionally, probe 1 was successfully utilized to visualize the polarity distribution of live cells. Both of these probes are perfect candidates for studying polarity in vitro and even in live systems.


Assuntos
Compostos de Boro , Corantes Fluorescentes , Solventes , Espectrometria de Fluorescência
18.
Orv Hetil ; 162(36): 1451-1458, 2021 09 05.
Artigo em Húngaro | MEDLINE | ID: mdl-34482291

RESUMO

Összefoglaló. Bevezetés: A myeloma multiplex mindmáig alapvetoen gyógyíthatatlan betegség, ezért nagy klinikai jelentoségük van az eredményes mento kezeléseknek. A szájon át adható elso proteaszómagátlóval, az ixazomibbal kiegészített lenalidomid-dexametazon terápia jól tolerálható, csak orális szerekbol álló kombináció, mely hazánkban 2015 áprilisától kezdodoen a "Named Patient Program" keretén belül vált elérhetové relabált, refrakter myeloma multiplexes betegek kezelésére. Célkituzés: Kutatásunk célja az ixazomib-lenalidomid-dexametazon kezelés mellett a hosszú távon progressziómentes túlélok célzott vizsgálata. Módszer: A program keretében összesen 7 centrumban 80 visszaeso beteg részesült e triplet kezelésben, adataikat retrospektíven elemeztük. Leíró statisztikai és Kaplan-Meier-analízist végeztünk. Eredmények: A betegek nagyobb hányada reagált: 63,75%-os válaszarány mellett 14 (17,5%) betegnél nem volt terápiás válasz/stabil betegség alakult ki, és 15-nél (18,75%) a betegség a kezelés mellett is progrediált. A progressziómentes túlélés a teljes betegcsoportban 10,6 hónapnak adódott, ugyanakkor 16 beteg (18,75%) két éven túl progressziómentesnek bizonyult, sot közülük 11-nél a betegség még 3 év után sem progrediált. Tanulmányunkban a fenti, hosszú távú túlélo betegcsoport tulajdonságait tárjuk fel. Megbeszélés: A folyamatos terápia a myeloma multiplex kezelésében meghatározóvá vált. Ezért fontos ismernünk, hogy kik lehetnek azok a betegek, akik különösen sokat profitálnak egy bizonyos terápiából. A hosszú távon progressziómentes túlélok között az immunglobulin-nehézláncot érinto transzlokációk vagy triszómiák közül (trend szintjén) az utóbbiak kedvezobb progressziómentes túléléssel bírtak, de progressziómentes platót mindkét betegcsoportban észleltünk. A betegség tumortömegét méro nemzetközi stádiumbeosztás (ISS) nem jelezte elore a hosszú túlélést. Gyógyszerelhagyáshoz vezeto mellékhatást a hosszú távú túlélo csoportban egyet sem regisztráltunk; az észlelt mellékhatások nagy része enyhe volt. Következtetések: Munkánk során az ixazomib-lenalidomid-dexametazon kombinációt effektívnek és biztonságosnak találtuk relabált, refrakter myeloma multiplex kezelésére, mely a betegek mintegy hatodánál több éven át eredményesen alkalmazható. Cikkünkkel a hazai beteganyagon szerzett tapasztalatainkat szeretnénk megosztani a COVID-19-világjárvány alatt különösen aktuálissá vált, tisztán orális terápiás lehetoségrol. Orv Hetil. 2021; 162(36): 1451-1458. INTRODUCTION: Despite great advances in therapy, multiple myeloma is still a largely incurable disease, therefore the importance of salvage therapies is paramount. The first oral proteasome inhibitor ixazomib in combination with lenalidomide-dexamethasone is a tolerable, orally administered regime, which has become available for Hungarian relapsed, refractory multiple myeloma patients from April 2015 in the Named Patient Program. OBJECTIVE: Our goal was to investigate the long-time progression-free surviving patient population treated with the ixazomib-lenalidomide-dexamethasone triplet. METHOD: We retrospectively studied a total of 80 patients from 7 centers who received the triplet combination. Survival analyses were performed. RESULTS: Two-third of the patients responded: the overall response rate was 63.75%. 14 patients (17.5%) did not respond/had stable disease and 15 patients (18.75%) outright progressed upon therapy. Although progression-free survival was only 10.6 months for the entire patient cohort, the disease in a subgroup of 16 patients did not progress within two years. In fact, 11 of them were still in sustained remission after 3 years of therapy. Our goal was to analyze the characteristics of this subgroup. DISCUSSION: The idea of long-term therapy of multiple myeloma is gaining widespread acceptance. Therefore it is important to know which patients may benefit the most from certain therapies. Among these 16 long-term responder patients, reciprocal translocation of the immunoglobulin heavy chain seemed to lack an adverse impact on progression-free survival; comparable to trisomies, both curves had a progression-free plateau. The International Staging System (ISS) score at the start of therapy did not predict long-term survivorship. Most of the side effects in this subgroup were mild, manageable, none led to therapy discontinuation. CONCLUSION: Ixazomib-lenalidomide-dexamethasone was confirmed to be an effective and safe combination for relapsed, refractory multiple myeloma, and one-sixth of the treated patients were able to receive it for several years, effectively. This fully oral therapeutic option is at its best during the present COVID-19 pandemic. Orv Hetil. 2021; 162(36): 1451-1458.


Assuntos
Compostos de Boro/uso terapêutico , Dexametasona/uso terapêutico , Glicina/uso terapêutico , Lenalidomida/uso terapêutico , Mieloma Múltiplo , Glicina/análogos & derivados , Humanos , Mieloma Múltiplo/tratamento farmacológico , Intervalo Livre de Progressão , Estudos Retrospectivos
19.
Langmuir ; 37(37): 10934-10944, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34496213

RESUMO

Processing boron nitride nanotubes (BNNTs) for applications ranging from nanomedicine to electronics generally requires dispersions of nanotubes that are stable in various compounds and solvents. We show that alcohol/water cosolvents, particularly isopropyl alcohol (IPA), are essential for the complexation of BNNTs with DNA under mild bath sonication. The resulting DNA-wrapped BNNT complexes are highly stable during purification and solvent exchange from cosolvents to water, providing potential for the versatile liquid-phase processing of BNNTs. Via molecular dynamics simulations, we demonstrate that IPA assists in the solvation of BNNTs due to its pseudosurfactant nature by verifying that water is replaced in the solvation layer as IPA is added. We quantify the solvation free energy of BNNTs in various IPA/water mixtures and observe a nonmonotonic trend, highlighting the importance of utilizing solvent-nanotube interactions in nanomaterial dispersions. Additionally, we show that nanotube lengths can be characterized by rheology measurements via determining the viscosity of dilute dispersions of DNA-BNNTs. This represents the bulk sample property in the liquid state, as compared to conventional imaging techniques that require surface deposition and drying. Our results also demonstrate that BNNT dispersions exhibit the rheological behavior of dilute Brownian rigid rods, which can be further exploited for the controlled processing and property enhancement of BNNT-enabled assemblies such as films and fibers.


Assuntos
Nanotubos , Compostos de Boro , DNA , Água
20.
Chem Commun (Camb) ; 57(71): 8953-8956, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34486586

RESUMO

A reliable copper-mediated nucleophilic radiosynthesis of the PET imaging probe [18F]FBPA was developed using novel aryldiboron precursors. The carrier-free [18F]FBPA with radiochemical purity >99% was prepared routinely via the two-step synthesis with an automatic module and can be used for clinical PET imaging of tumours.


Assuntos
Compostos de Boro/química , Fenilalanina/análogos & derivados , Compostos Radiofarmacêuticos/química , Animais , Compostos de Boro/síntese química , Radioisótopos de Flúor/química , Fenilalanina/síntese química , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/síntese química
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