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1.
Nature ; 630(8016): 509-515, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38750366

RESUMO

Temperature profoundly affects macromolecular function, particularly in proteins with temperature sensitivity1,2. However, its impact is often overlooked in biophysical studies that are typically performed at non-physiological temperatures, potentially leading to inaccurate mechanistic and pharmacological insights. Here we demonstrate temperature-dependent changes in the structure and function of TRPM4, a temperature-sensitive Ca2+-activated ion channel3-7. By studying TRPM4 prepared at physiological temperature using single-particle cryo-electron microscopy, we identified a 'warm' conformation that is distinct from those observed at lower temperatures. This conformation is driven by a temperature-dependent Ca2+-binding site in the intracellular domain, and is essential for TRPM4 function in physiological contexts. We demonstrated that ligands, exemplified by decavanadate (a positive modulator)8 and ATP (an inhibitor)9, bind to different locations of TRPM4 at physiological temperatures than at lower temperatures10,11, and that these sites have bona fide functional relevance. We elucidated the TRPM4 gating mechanism by capturing structural snapshots of its different functional states at physiological temperatures, revealing the channel opening that is not observed at lower temperatures. Our study provides an example of temperature-dependent ligand recognition and modulation of an ion channel, underscoring the importance of studying macromolecules at physiological temperatures. It also provides a potential molecular framework for deciphering how thermosensitive TRPM channels perceive temperature changes.


Assuntos
Trifosfato de Adenosina , Cálcio , Microscopia Crioeletrônica , Ativação do Canal Iônico , Modelos Moleculares , Canais de Cátion TRPM , Temperatura , Canais de Cátion TRPM/metabolismo , Canais de Cátion TRPM/química , Ligantes , Ativação do Canal Iônico/efeitos dos fármacos , Humanos , Trifosfato de Adenosina/metabolismo , Sítios de Ligação , Cálcio/metabolismo , Vanadatos/química , Vanadatos/farmacologia , Vanadatos/metabolismo , Animais , Células HEK293 , Ligação Proteica , Domínios Proteicos
2.
Environ Toxicol Pharmacol ; 108: 104465, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38734396

RESUMO

Malaria represents the greatest global health burden among all parasitic diseases, with drug resistance representing the primary obstacle to control efforts. Sodium metavanadate (NaVO3) exhibits antimalarial activity against the Plasmodium yoelii yoelii (Pyy), yet its precise antimalarial mechanism remains elusive. This study aimed to assess the antimalarial potential of NaVO3, evaluate its genotoxicity, and determine the production of reactive oxygen and nitrogen species (ROS/RNS) in Pyy. CD-1 mice were infected and divided into two groups: one treated orally with NaVO3 (10 mg/kg/day for 4 days) and the other untreated. A 50% decrease in parasitemia was observed in treated mice. All experimental days demonstrated DNA damage in exposed parasites, along with an increase in ROS and RNS on the fifth day, suggesting a possible parasitostatic effect. The results indicate that DNA is a target of NaVO3, but further studies are necessary to fully elucidate the mechanisms underlying its antimalarial activity.


Assuntos
Antimaláricos , Dano ao DNA , Plasmodium yoelii , Espécies Reativas de Nitrogênio , Espécies Reativas de Oxigênio , Vanadatos , Animais , Plasmodium yoelii/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Antimaláricos/toxicidade , Antimaláricos/farmacologia , Espécies Reativas de Nitrogênio/metabolismo , Vanadatos/toxicidade , Vanadatos/farmacologia , Malária/tratamento farmacológico , Masculino , Parasitemia , Feminino
3.
J Inorg Biochem ; 257: 112610, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38761580

RESUMO

Drug resistance has been a major problem for cancer chemotherapy, especially for glioblastoma multiforme that is aggressive, heterogeneous and recurrent with <3% of a five-year survival and limited methods of clinical treatment. To overcome the problem, great efforts have recently been put in searching for agents inducing death of tumor cells via various non-apoptotic pathways. In the present work, we report for the first time that vanadyl complexes, i.e. bis(acetylacetonato)oxidovanadium (IV) (VO(acac)2), can cause mitotic catastrophe and methuotic death featured by catastrophic macropinocytic vacuole accumulation particularly in glioblastoma cells (GCs). Hence, VO(acac)2 strongly suppressed growth of GCs with both in vitro (IC50 = 4-6 µM) and in vivo models, and is much more potent than the current standard-of-care drug Temozolomide. The selective index is as high as ∼10 or more on GCs over normal neural cells. Importantly, GCs respond well to vanadium treatment regardless whether they are carrying IDH1 wild type gene that causes drug resistance. VO(acac)2 may induce methuosis via the Rac-Mitogen-activated protein kinase kinase 4 (MKK4)-c-Jun N-terminal kinase (JNK) signaling pathway. Furthermore, VO(acac)2-induced methuosis is not through a immunogenicity mechanism, making vanadyl complexes safe for interventional therapy. Overall, our results may encourage development of novel vanadium complexes promising for treatment of neural malignant tumor cells.


Assuntos
Complexos de Coordenação , Glioblastoma , Mitose , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Glioblastoma/metabolismo , Humanos , Mitose/efeitos dos fármacos , Animais , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/química , Camundongos , Vanadatos/farmacologia , Vanadatos/química , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Camundongos Nus
4.
Water Res ; 257: 121747, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38733964

RESUMO

Contamination of aquifers by a combination of vanadate [V(V)] and nitrate (NO3-) is widespread nowadays. Although bioremediation of V(V)- and nitrate-contaminated environments is possible, only a limited number of functional species have been identified to date. The present study demonstrates the effectiveness of V(V) reduction and denitrification by a denitrifying bacterium Acidovorax sp. strain BoFeN1. The V(V) removal efficiency was 76.5 ± 5.41 % during 120 h incubation, with complete removal of NO3- within 48 h. Inhibitor experiments confirmed the involvement of electron transport substances and denitrifying enzymes in the bioreduction of V(V) and NO3-. Cyt c and riboflavin were important for extracellular V(V) reduction, with quinone and EPS more significant for NO3- removal. Intracellular reductive compounds including glutathione and NADH directly reduce V(V) and NO3-. Reverse transcription quantitative PCR confirmed the important roles of nirK and napA genes in regulating V(V) reduction and denitrification. Bioaugmentation by strain BoFeN1 increased V(V) and NO3- removal efficiency by 55.3 % ± 2.78 % and 42.1 % ± 1.04 % for samples from a contaminated aquifer. This study proposes new microbial resources for the bioremediation of V(V) and NO3-contaminated aquifers, and contributes to our understanding of coupled vanadium, nitrogen, and carbon biogeochemical processes.


Assuntos
Biodegradação Ambiental , Comamonadaceae , Desnitrificação , Nitratos , Oxirredução , Vanadatos , Comamonadaceae/metabolismo , Comamonadaceae/genética , Vanadatos/metabolismo , Nitratos/metabolismo , Poluentes Químicos da Água/metabolismo , Água Subterrânea/microbiologia
5.
Environ Sci Technol ; 58(21): 9456-9465, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38745405

RESUMO

The elimination of uranium from radioactive wastewater is crucial for the safe management and operation of environmental remediation. Here, we present a layered vanadate with high acid/base stability, [Me2NH2]V3O7, as an excellent ion exchanger capturing uranyl from highly complex aqueous solutions. The material possesses an indirect band gap, ferromagnetic characteristic and a flower-like morphology comprising parallel nanosheets. The layered structure of [Me2NH2]V3O7 is predominantly upheld by the H-bond interaction between anionic framework [V3O7]nn- and intercalated [Me2NH2]+. The [Me2NH2]+ within [Me2NH2]V3O7 can be readily exchanged with UO22+. [Me2NH2]V3O7 exhibits high exchange capacity (qm = 176.19 mg/g), fast kinetics (within 15 min), high removal efficiencies (>99%), and good selectivity against an excess of interfering ions. It also displays activity for UO22+ ion exchange over a wide pH range (2.00-7.12). More importantly, [Me2NH2]V3O7 has the capability to effectively remove low-concentration uranium, yielding a residual U concentration of 13 ppb, which falls below the EPA-defined acceptable limit of 30 ppb in typical drinking water. [Me2NH2]V3O7 can also efficiently separate UO22+ from Cs+ or Sr2+ achieving the highest separation factors (SFU/Cs of 589 and SFU/Sr of 227) to date. The BOMD and DFT calculations reveal that the driving force of ion exchange is dominated by the interaction between UO22+ and [V3O7]nn-, whereas the ion exchange rate is influenced by the mobility of UO22+ and [Me2NH2]+. Our experimental findings indicate that [Me2NH2]V3O7 can be considered as a promising uranium scavenger for environmental remediation. Additionally, the simulation results provide valuable mechanistic interpretations for ion exchange and serve as a reference for designing novel ion exchangers.


Assuntos
Urânio , Vanadatos , Urânio/química , Vanadatos/química , Troca Iônica , Poluentes Radioativos da Água/química , Cinética
6.
J Dent ; 145: 104984, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38583645

RESUMO

OBJECTIVES: To incorporate the nanostructured silver vanadate decorated with silver nanoparticles (AgVO3) into denture base materials: heat-cured (HC) and 3D printed (3DP) resins, at concentrations of 2.5 %, 5 %, and 10 %; and to evaluate the antimicrobial activity in two multi-species biofilm: (1) Candida albicans, Candida glabrata, and Streptococcus mutans, (2) Candida albicans, Pseudomonas aeruginosa, and Staphylococcus aureus, and the wettability. METHODS: The AgVO3 was added to the HC powder, and printed samples were coated with 3DP with AgVO3 incorporated. After biofilm formation, the antimicrobial activity was evaluated by colony forming units per milliliter (CFU/mL), metabolic activity, and epifluorescence microscopy. Wettability was assessed by the contact angles with water and artificial saliva. RESULTS: In biofilm (1), HC-5 % and HC-10 % showed activity against S. mutans, HC-10 % against C. glabrata, and HC-10 % and 3DP-10 % had higher CFU/mL of C. albicans. 3DP-5 % had lower metabolic activity than the 3DP control. In biofilm (2), HC-10 % reduced S. aureus and P. aeruginosa, and HC-5 %, 3DP-2.5 %, and 3DP-5 % reduced S. aureus. 3DP incorporated with AgVO3, HC-5 %, and HC-10 % reduced biofilm (2) metabolic activity. 3DP-5 % and 3DP-10 % increased wettability with water and saliva. CONCLUSION: HC-10 % was effective against C. glabrata, S. mutans, P. aeruginosa, and S. aureus, and HC-5 % reduced S. mutans and S. aureus. For 3DP, 2.5 % and 5 % reduced S. aureus. The incorporation of AgVO3 into both resins reduced the metabolic activity of biofilms but had no effect on C. albicans. The wettability of the 3DP with water and saliva increased with the addition of AgVO3. CLINICAL SIGNIFICANCE: The incorporation of silver vanadate into the denture base materials provides antimicrobial efficacy and can prevent the aggravation of oral and systemic diseases. The incorporation of nanomaterials into printed resins is challenging and the coating is an alternative to obtain the inner denture base with antimicrobial effect.


Assuntos
Biofilmes , Candida albicans , Bases de Dentadura , Nanopartículas Metálicas , Pseudomonas aeruginosa , Prata , Staphylococcus aureus , Streptococcus mutans , Vanadatos , Molhabilidade , Biofilmes/efeitos dos fármacos , Streptococcus mutans/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Vanadatos/farmacologia , Vanadatos/química , Pseudomonas aeruginosa/efeitos dos fármacos , Prata/farmacologia , Prata/química , Bases de Dentadura/microbiologia , Nanopartículas Metálicas/química , Anti-Infecciosos/farmacologia , Candida glabrata/efeitos dos fármacos , Impressão Tridimensional , Teste de Materiais , Humanos , Nanoestruturas , Compostos de Prata/farmacologia , Compostos de Prata/química , Materiais Dentários/química , Materiais Dentários/farmacologia
8.
ACS Appl Mater Interfaces ; 16(17): 21975-21986, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38626357

RESUMO

The development of high-performance biosensors is a key focus in the nanozyme field, but the current limitations in biocompatibility and recyclability hinder their broader applications. Herein, we address these challenges by constructing core-shell nanohybrids with biocompatible poly(ethylene glycol) (PEG) modification using a galvanic replacement reaction between orthovanadate ions and liquid metal (LM) (VOx@EGaIn-PEG). By leveraging the excellent charge transfer properties and the low band gap of the LM surface oxide, the VOx@EGaIn-PEG heterojunction can effectively convert hydrogen peroxide into hydroxyl radicals, demonstrating excellent peroxidase-like activity and stability (Km = 490 µM, vmax = 1.206 µM/s). The unique self-healing characteristics of LM further enable the recovery and regeneration of VOx@EGaIn-PEG nanozymes, thereby significantly reducing the cost of biological detection. Building upon this, we developed a nanozyme colorimetric sensor suitable for biological systems and integrated it with a smartphone to create an efficient quantitative detection platform. This platform allows for the convenient and sensitive detection of glucose in serum samples, exhibiting a good linear relationship in the range of 10-500 µM and a detection limit of 2.35 µM. The remarkable catalytic potential of LM, combined with its biocompatibility and regenerative properties, offers valuable insights for applications in catalysis and biomedical fields.


Assuntos
Técnicas Biossensoriais , Polietilenoglicóis , Polietilenoglicóis/química , Técnicas Biossensoriais/métodos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/análise , Peroxidase/química , Peroxidase/metabolismo , Catálise , Humanos , Vanadatos/química , Glicemia/análise , Materiais Biomiméticos/química , Limite de Detecção , Compostos de Vanádio/química
9.
Environ Sci Pollut Res Int ; 31(20): 30085-30098, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38598155

RESUMO

Formaldehyde (HCHO) is one of the primary indoor air pollutants, and efficiently eliminating it, especially at low concentrations, remains challenging. In this study, BiVO4-TiO2 catalyst was developed using ultrasonic blending technology for the photocatalytic oxidation of low-level indoor HCHO. The crystal structure, surface morphology, element distribution, and active oxidation species of the catalyst were examined using XRD, SEM, TEM, UV-Vis, EDS, and ESR techniques. Our results demonstrated that the BiVO4-TiO2 catalyst, prepared by ultrasonic blending, exhibited good oxidation performance and stability. The HCHO concentration reduced from 1.050 to 0.030 mg/m3 within 48 h, achieving a removal rate of 97.1%. The synergy between BiVO4 and TiO2 enhanced the efficiency of separating photogenerated carriers and minimized the likelihood of recombination between photogenerated electrons and holes. Additionally, this synergy significantly enhanced the presence of hydroxyl radicals (·OH) on the catalyst, resulting in an oxidation performance superior to that of either BiVO4 or TiO2. Our research offers valuable insights for the development of new photocatalysts to address HCHO pollution.


Assuntos
Bismuto , Formaldeído , Oxirredução , Titânio , Vanadatos , Formaldeído/química , Titânio/química , Vanadatos/química , Bismuto/química , Catálise , Luz , Ultrassom
10.
Langmuir ; 40(17): 9155-9169, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38641555

RESUMO

A lack of eco-friendly, highly active photocatalyst for peroxymonosulfate (PMS) activation and unclear environmental risks are significant challenges. Herein, we developed a double S-scheme Fe2O3/BiVO4(110)/BiVO4(010)/Fe2O3 photocatalyst to activate PMS and investigated its impact on wheat seed germination. We observed an improvement in charge separation by depositing Fe2O3 on the (010) and (110) surfaces of BiVO4. This enhancement is attributed to the formation of a dual S-scheme charge transfer mechanism at the interfaces of Fe2O3/BiVO4(110) and BiVO4(010)/Fe2O3. By introducing PMS into the system, photogenerated electrons effectively activate PMS, generating reactive oxygen species (ROS) such as hydroxyl radicals (·OH) and sulfate radicals (SO4·-). Among the tested systems, the 20% Fe2O3/BiVO4/Vis/PMS system exhibits the highest catalytic efficiency for norfloxacin (NOR) removal, reaching 95% in 40 min. This is twice the catalytic efficiency of the Fe2O3/BiVO4/PMS system, 1.8 times that of the Fe2O3/BiVO4 system, and 5 times that of the BiVO4 system. Seed germination experiments revealed that Fe2O3/BiVO4 heterojunction was beneficial for wheat seed germination, while PMS had a significant negative effect. This study provides valuable insights into the development of efficient and sustainable photocatalytic systems for the removal of organic pollutants from wastewater.


Assuntos
Bismuto , Compostos Férricos , Luz , Norfloxacino , Peróxidos , Vanadatos , Vanadatos/química , Vanadatos/efeitos da radiação , Bismuto/química , Norfloxacino/química , Norfloxacino/efeitos da radiação , Catálise/efeitos da radiação , Compostos Férricos/química , Peróxidos/química , Processos Fotoquímicos , Triticum/química , Triticum/efeitos da radiação
11.
Biomolecules ; 14(3)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38540742

RESUMO

Recently, several ATP-binding cassette (ABC) importers have been found to adopt the typical fold of type IV ABC exporters. Presumably, these importers would function under the transport scheme of "alternating access" like those exporters, cycling through inward-open, occluded, and outward-open conformations. Understanding how the exporter-like importers move substrates in the opposite direction requires structural studies on all the major conformations. To shed light on this, here we report the structure of yersiniabactin importer YbtPQ from uropathogenic Escherichia coli in the occluded conformation trapped by ADP-vanadate (ADP-Vi) at a 3.1 Å resolution determined by cryo-electron microscopy. The structure shows unusual local rearrangements in multiple helices and loops in its transmembrane domains (TMDs). In addition, the dimerization of the nucleotide-binding domains (NBDs) promoted by the vanadate trapping is highlighted by the "screwdriver" action at one of the two hinge points. These structural observations are rare and thus provide valuable information to understand the structural plasticity of the exporter-like ABC importers.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Vanadatos , Conformação Proteica , Transportadores de Cassetes de Ligação de ATP/metabolismo , Microscopia Crioeletrônica , Modelos Moleculares , Trifosfato de Adenosina
12.
Inorg Chem ; 63(11): 4997-5011, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38428015

RESUMO

We study active-site models of nonheme iron hydroxylases and their vanadium-based mimics using density functional theory to determine if vanadyl is a faithful structural mimic. We identify crucial structural and energetic differences between ferryl and vanadyl isomers owing to the differences in their ground electronic states, i.e., high spin (HS) for Fe and low spin (LS) for V. For the succinate cofactor bound to the ferryl intermediate, we predict facile interconversion between monodentate and bidentate coordination isomers for ferryl species but difficult rearrangement for vanadyl mimics. We study isomerization of the oxo intermediate between axial and equatorial positions and find the ferryl potential energy surface to be characterized by a large barrier of ca. 10 kcal/mol that is completely absent for the vanadyl mimic. This analysis reveals even starker contrasts between Fe and V in hydroxylases than those observed for this metal substitution in nonheme halogenases. Analysis of the relative bond strengths of coordinating carboxylate ligands for Fe and V reveals that all of the ligands show stronger binding to V than Fe owing to the LS ground state of V in contrast to the HS ground state of Fe, highlighting the limitations of vanadyl mimics of native nonheme iron hydroxylases.


Assuntos
Ferro , Vanádio , Vanadatos , Eletrônica , Oxigenases de Função Mista
13.
Mar Pollut Bull ; 201: 116205, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38452629

RESUMO

To mitigate marine pollution, we improved the photo-Fenton reaction of modified nanoscale CuO/BiVO4 photocatalysts to resolve the challenge of efficient microplastic degradation in wastewater treatment. Material property analysis and computational results revealed that deposition of CuO onto BiVO4 nanocomposites improved photocatalytic activity by promoting an excess of electrons in CuO and surface charge transfer, resulting in an increased production of e--h+ for ROS generation via H2O2 activation. 1O2 was dominated and identified through quenching experiments, XPS analysis, and EPR. ROS generation increased via H2O2 activation, causing major surface abrasion and increased carbonyl and vinyl indices in microplastics. Treated water had minimal impact on Lycopersicon esculentum Mill. seedling growth but caused considerable mortality in cell lines and Moina macrocopa mortality at greater dosages due to their sensitivity to ions and H2O2 residuals. Overall, this treatment can effectively degrade microplastics, but the dilution of treated water is still needed before being discharged.


Assuntos
Bismuto , Cladocera , Microplásticos , Plásticos , Vanadatos , Peróxido de Hidrogênio , Espécies Reativas de Oxigênio , Cobre , Água , Meio Ambiente
14.
Sensors (Basel) ; 24(6)2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38544072

RESUMO

Dimetridazole (DMZ), a nitroimidazole derivative, is a notable antibiotic that has garnered growing interest in the medical community owing to its noteworthy pharmacological and toxicological properties. Increasing interest is being directed toward developing high-performance sensors for continuous monitoring of DMZ in food samples. This research investigated an electrochemical sensor-based nano-sized ErVO4 attached to a sheet-like g-CN-coated glassy carbon electrode to determine dimetridazole (DMZ). The chemical structure and morphological characterization of synthesized ErVO4@g-CN were analyzed with XRD, FTIR, TEM, and EDS. Irregular shapes of ErVO4 nanoparticles are approximately 15 nm. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were followed to examine the electrochemical performance in pH 7 phosphate buffer solution for higher performance. This electrochemical sensor showed a low detection limit (LOD) of 1 nM over a wide linear range of 0.5 to 863.5 µM. Also, selectivity, stability, repeatability, and reproducibility studies were investigated. Furthermore, this electrochemical sensor was applied to real-time milk sample analysis for the detection of analytes.


Assuntos
Érbio , Grafite , Compostos de Nitrogênio , Vanadatos , Animais , Reprodutibilidade dos Testes , Leite , Dimetridazol , Carbono/química , Técnicas Eletroquímicas , Eletrodos , Limite de Detecção
15.
J Inorg Biochem ; 255: 112533, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38547784

RESUMO

Two bases-decavanadates coordination compounds [(C6H13N4)2][Mg(H2O)6]2[O28V10].6H2O (1) and [(C7H11N2)4][Mg(H2O)6][O28V10].4H2O (2) have been synthesized and well characterized using vibrational spectroscopy (infrared), UV-Visible analysis and single crystal X-ray diffraction technique. The formula unit, for both compounds, is composed by the decavanadate [V10O28]6-, hydrated magnesium ion, a counter anion and free water molecules. The transition metal adopts octahedral geometries in both compound (1) and (2). The existence of a multitude of hydrogen bonding interactions for both compounds provides a stable three-dimensional supramolecular structure. Optical absorption reveals a band gap energy indicating the semi-conductive nature of the compound. In this study, the cytotoxic and the anti-proliferative activities of compounds (1) and (2) on human cancer cells (U87 and MDA-MB-231) were investigated. Both compounds demonstrated dose-dependent anti-proliferative activity on U87 and MDA-MB-231 with respective IC50 values of 0.82 and 0.31 µM and 1.4 and 1.75 µM. These data provide evidence on the potential anticancer activity of [(C6H13N4)2][Mg(H2O)6]2[O28V10].6H2O and [(C7H11N2)4][Mg(H2O)2][O28V10].4H2O. Molecular docking of the compounds was also examined. Molecular docking studies were performed for both compounds against four target receptors and revealed better binding affinity with these targets in comparison to Cisplatin. Moreover, molecular docking investigations suggest that these compounds may function as potential inhibitors of proteins in brain and breast cells, exhibiting greater efficiency compared to Cisplatin.


Assuntos
Antineoplásicos , Vanadatos , Humanos , Simulação de Acoplamento Molecular , Vanadatos/química , Cisplatino/farmacologia , Cristalografia por Raios X , Estrutura Molecular , Antineoplásicos/química , Proliferação de Células
16.
Eur J Prosthodont Restor Dent ; 32(2): 203-211, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38373220

RESUMO

Alternatives have been sought to add an antimicrobial property to denture adhesives. This study evaluated the antimicrobial potential of adhesives associated with nanostructured silver vanadate decorated with silver nanoparticles (ß-AgVO3). Specimens in acrylic resin were treated with the adhesives associated with ß-AgVO3 (1%, 2.5%, 5% and 10%). As control, specimens treated only with Ultra Corega Cream (UCC) or Ultra Corega Powder (UCP) adhesive were used. Multispecies biofilm of Candida albicans, Candida glabrata, Streptococcus mutans and Staphylococcus aureus was evaluated by counting colony forming units per milliliter (CFU/mL), colorimetric assay and fluorescence microscopy. The data were analyzed using the two-way analysis of variance (ANOVA) and Bonferroni multiple comparisons test (α=0.05). For both adhesives, a small amount of ß-AgVO3 (1%) completely inhibited S. mutans (P⟨0.05). For the other microorganisms, there was a reduction in metabolic activity and complete inhibition in the groups with intermediate or greater amounts of nanomaterial (P⟨0.05), except for C. albicans, which was reduced (P⟨0.05) but not completely inhibited in UCP. Microscopy that showed less biofilm in the groups with ß-AgVO3 and in the UCC than UCP. Denture adhesives in powder and cream form with ß-AgVO3 showed potential antimicrobial activity against multispecies biofilm. Powder adhesive showed higher biofilm formation.


Assuntos
Resinas Acrílicas , Biofilmes , Candida albicans , Prata , Streptococcus mutans , Vanadatos , Biofilmes/efeitos dos fármacos , Vanadatos/farmacologia , Vanadatos/química , Streptococcus mutans/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Prata/farmacologia , Prata/química , Staphylococcus aureus/efeitos dos fármacos , Anti-Infecciosos/farmacologia , Nanopartículas Metálicas , Propriedades de Superfície , Cimentos Dentários/farmacologia , Compostos de Prata/farmacologia , Candida glabrata/efeitos dos fármacos
17.
J Dent ; 145: 104836, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38199325

RESUMO

OBJECTIVE: To investigate the impact of incorporating the antimicrobial nanomaterial ß-AgVO3 into orthodontic resin, focusing on degree of conversion, surface characteristics, microhardness, adhesion properties, and antimicrobial activity. METHODS: The 3 M Transbond XT resin underwent modification, resulting in three groups (Control, 2.5% addition, 5% addition) with 20 specimens each. Fourier transform infrared spectroscopy assessed monomer conversion. Laser confocal microscopy examined surface roughness, and microhardness was evaluated using Knoop protocols. Shear strength was measured before and after artificial aging on 36 premolar teeth. Microbiological analysis against S. mutans and S. sanguinis was conducted using the agar diffusion method. RESULTS: Degree of conversion remained unaffected by time (P = 0.797), concentration (P = 0.438), or their interaction (P = 0.187). The 5% group exhibited the lowest surface roughness, differing significantly from the control group (P = 0.045). Microhardness showed no significant differences between concentrations (P = 0.740). Shear strength was highest in the control group (P < 0.001). No significant differences were observed in the samples with or without thermocycling (P = 0.759). Microbial analysis revealed concentration-dependent variations, with the 5% group exhibiting the largest inhibition halo (P < 0.001). CONCLUSIONS: Incorporating ß-AgVO3 at 2.5% and 5% concentrations led to significant differences in surface roughness, adhesion, and antimicrobial activity. Overall, resin modification positively impacted degree of conversion, surface characteristics, microhardness, and antimicrobial activity. Further research is warranted to determine clinically optimal concentrations that maximize antimicrobial benefits while minimizing adverse effects on adhesion properties. CLINICAL SIGNIFICANCE: Incorporating ß-AgVO3 into orthodontic resin could improve patient quality of life by prolonging intervention durability and reducing the impact of cariogenic microorganisms. The study's findings also hold promise for the industry, paving the way for the development of new materials with antimicrobial properties for potential applications in the health sector.


Assuntos
Teste de Materiais , Nanopartículas Metálicas , Resistência ao Cisalhamento , Prata , Streptococcus mutans , Propriedades de Superfície , Vanadatos , Streptococcus mutans/efeitos dos fármacos , Humanos , Prata/química , Prata/farmacologia , Vanadatos/química , Vanadatos/farmacologia , Nanopartículas Metálicas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Dureza , Cimentos de Resina/química , Streptococcus sanguis/efeitos dos fármacos , Braquetes Ortodônticos/microbiologia , Microscopia Confocal , Nanoestruturas/química , Aderência Bacteriana/efeitos dos fármacos , Compostos de Prata/farmacologia , Compostos de Prata/química
18.
J Trace Elem Med Biol ; 83: 127381, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38211406

RESUMO

BACKGROUND: Fungi absorb and solubilize a broad spectrum of heavy metals such as vanadium (V), which makes them a main route of its entry into the biosphere. V as vanadate (V5+) is a potential medical agent due to its many metabolic actions such as interaction with phosphates in the cell, and especially its insulin-mimetic activity. Antidiabetic activity of V-enriched fungi has been studied in recent years, but the biological and chemical bases of vanadium action and status in fungi in general are poorly understood, with almost no information on edible fungi. METHODS: This manuscript gives a deeper insight into the interaction of V5+ with Coprinellus truncorum, an edible autochthonous species widely distributed in Europe and North America. Vanadium uptake and accumulation as V5+ was studied by 51V NMR, while the reducing abilities of the mycelium were determined by EPR. 31P NMR was used to determine its effects on the metabolism of phosphate compounds, with particular focus on phosphate sugars identified using HPLC. RESULTS: Vanadate enters the mycelium in monomeric form and shows no immediate detrimental effects on intracellular pH or polyphosphate (PPc) levels, even when applied at physiologically high concentrations (20 mM Na3VO4). Once absorbed, it is partially reduced to less toxic vanadyl (V4+) with notable unreduced portion, which leads to a large increase in phosphorylated sugar levels, especially glucose-1-phosphate (G1P) and fructose-6-phosphate (F6P). CONCLUSIONS: Preservation of pH and especially PPc reflects maintenance of the energy status of the mycelium, i.e., its tolerance to high V5+ concentrations. Rise in G1P and F6P levels implies that the main targets of V5+ are most likely phosphoglucomutase and phosphoglucokinase(s), enzymes involved in early stages of G6P transformation in glycolysis and glycogen metabolism. This study recommends C. truncorum for further investigation as a potential antidiabetic agent.


Assuntos
Agaricales , Vanadatos , Vanádio , Vanádio/análise , Vanadatos/química , Biomassa , Fosfatos/análise , Micélio/metabolismo
19.
Sci Rep ; 14(1): 1591, 2024 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238361

RESUMO

Since quinolone is a kind of synthetic broad-spectrum antibacterial drugs, with the widespread use of this class of antibiotics, the risk and harm to human health have been attendant to the sewage containing quinolones which are discharged into the environment. Photocatalysis is considered as a promising technology for antibiotic degradation for its strong redox properties and reaction rate. As a metal oxidizing substance, Bismuth vanadate (BiVO4) is such a popular and hot material for the degradation of organic pollutants recently due to its good photocatalytic activity and chemical stability. Numerous studies have confirmed that BiVO4 composites can overcome the shortcomings of pure BiVO4 and cleave the main structure of quinolone under photocatalytic conditions. This paper mainly outlines the research progress on the preparation of BiVO4 composites and the degradation of quinolone antibiotics from the perspective of improving the catalysis and degrading the efficiency mechanism of BiVO4 composites.


Assuntos
Antibacterianos , Quinolonas , Humanos , Antibacterianos/química , Bismuto/química , Vanadatos/química , Catálise , Luz
20.
Food Chem ; 441: 138405, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38218142

RESUMO

Flavonoids or phenolic compounds are part of the daily intake of every human being. Though they are positive traders for metabolism, excessive intakes bring about detrimental impacts on human health. Herein, the anti-cancer capacitive nature quercetin (Qc) was electrochemically detected through the rare earth metal-based sphere like praseodymium vanadate (PrVO4) entrapped graphitic carbon nitride (g-CN) as electrode modifiers. The nanocomposite was prepared by the one-pot hydrothermal method and characterized by phase compositional and morphology-based techniques. The existing synergistic nature between the PrV@g-CN (praseodymium vanadate@graphitic carbon nitride) makes them have an enhanced electrochemical response towards the Qc than the individual material. The obtained cyclic voltammogram and differential pulse voltammogram profile show one major oxidation peak which is attributed to the conversion of quercetin to quercetin-o-quinone. The PrV@g-CN/GCE (GCE- glassy carbon electrode) shows a good electrochemical active surface area (A = 110 cm2) and linear range between 0.05 and 252.00 µM with a LOD (limit of detection) of 0.002 µM. Moreover, the PrV@g-CN/GCE exhibits good current retention (94.76 %) around 14 days and appreciable repeatability (RSD- 0.5 %) and reproducibility (RSD- 1.3 %) towards the Qc. The real-time implementation of the proposed sensor exhibits a good recovery range towards the black tea (95.00-98.10 %) and green tea (97.80-99.60 %).


Assuntos
Grafite , Nanocompostos , Compostos de Nitrogênio , Quercetina , Humanos , Flavonoides , Praseodímio , Vanadatos/química , Reprodutibilidade dos Testes , Limite de Detecção , Técnicas Eletroquímicas/métodos , Carbono/química , Eletrodos , Nanocompostos/química
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