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1.
Inorg Chem ; 63(25): 11542-11553, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38860865

RESUMEN

MOF-based materials, as bifunctional catalysts for electrocatalytic water splitting, play an important role in the application and development of clean fuel hydrogen energy. This study presents a series of novel 3D Co-based MOFs with layered networks, including [Co(4,4'-bipy)0.5(aip)(CH3OH)·H2O]n (Co-MOF 1), [Co2(1,3'-bit)(aip)2(CH3OH)·H2O]n (Co-MOF 2), [Co(4,4'-bipb)(aip)]n (Co-MOF 3), and [Co2(4,4'-bipe)(aip)2·1.5H2O]n (Co-MOF 4). Their single-crystal structures of Co-MOFs 1-4 are characterized and analyzed before being applied in alkaline solutions for water decomposition (OER and HER). The electrocatalytic tests indicate that Co-MOFs 1-4 exhibit a good performance. Notably, Co-MOF 4 exhibits great behavior which has low overpotentials of 94 and 188 mV (OER) as well as 185 and 352 mV (HER) at the currents of 10 and 100 mA cm-2, respectively. In comparison with Co-MOFs 1-3, Co-MOF 4 has the lowest Tafel slopes, highest ECSA, and smallest resistance. The immanent qualities, such as distinct interwoven long chain layered structure, unsaturated coordination modes, and synergistic catalytic qualities among Co ions, contribute to explaining the results. The fundamentals provide valuable information for the investigation of innovative MOF-based bifunctional electrocatalysts for overall water splitting.

2.
Fish Shellfish Immunol ; 149: 109604, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38710343

RESUMEN

MicroRNAs (miRNAs) are a crucial type of non-coding RNAs involved in post-transcriptional regulation. The playing essential regulatory roles in the NF-κB signaling pathway and modulate the host immune response to diverse pathogens by targeting IκBα. However, the regulatory mechanism of miRNAs in relation with IκBα in Sebastes schlegelii remains unclear. In our study, we identified two copies of IkBα gene in black rockfish (Sebastes schlegelii), namely IkBα1 and IkBα2. Moreover, we have discovered that miRNA-530 can activate the NF-κB signaling pathway by inhibiting the expression of IκBα, thereby inducing the inflammatory response. This project comprehensively investigated the interactive regulatory roles of miRNA-530 in the NF-κB signaling pathway at both cellular and in vivo levels, while also elucidating the regulatory relationships between miRNA-530 and IκBα. In conclusion, our research confirmed that miRNA-530 can target the 3'UTR region of IκBα, resulting in a decrease in the expression of IκBα at the post-transcriptional level and inhibiting its translation. The findings contribute to the understanding of the regulatory network of non-coding RNA in teleosts and its subsequent regulation of the NF-κB signaling pathway by miRNAs.


Asunto(s)
Regulación de la Expresión Génica , MicroARNs , Inhibidor NF-kappaB alfa , FN-kappa B , Transducción de Señal , MicroARNs/genética , MicroARNs/metabolismo , Animales , FN-kappa B/genética , FN-kappa B/metabolismo , Inhibidor NF-kappaB alfa/genética , Inhibidor NF-kappaB alfa/metabolismo , Regulación de la Expresión Génica/inmunología , Proteínas de Peces/genética , Proteínas de Peces/inmunología , Inmunidad Innata/genética , Peces/genética , Peces/inmunología , Perciformes/genética , Perciformes/inmunología
3.
Inorg Chem ; 63(1): 294-303, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38145954

RESUMEN

Converting CO2 to valuable chemicals and fuels is a viable method to establish a carbon-neutral energy cycle in the environment. Metal-organic frameworks (MOFs), characterized by dispersed active sites, high porosity, etc., have displayed a great application prospect in the electrochemical/chemical CO2 reduction reaction (CO2RR) process. Herein, we proposed a one-step production to establish a series of pillar-layered porous MOFs, [Co2(L)(bimb)]n (MOF 1) and [Co4(L)2(bidpe)2]n (MOF 2) [H4L = 5'-(4-carboxyphenyl)-(1,1':2',1″-terphenyl)-4,4',4″-tricarboxylic, bimb = 1,4-bis(imidazol-1-yl)-butane, bidpe = 4'-bis(imidazolyl) diphenyl ether], for preferential conversion of CO2 via ligand adjustment and increase of active sites' density. According to single-crystal X-ray diffraction studies, [Co2(L)(bimb)]n exhibits pillar-layered binuclear 3D frameworks with a 2,4,6-linked 3-nodes new topology structure, while [Co4(L)2(bidpe)2]n displays pillar-layered tetranuclear interspersed networks with a 4,6-linked 2-nodes fsc topology structure through a ligand adjustment strategy. Meanwhile, the pillar-layered structure of the MOFs with abundant active sites is conducive to mass diffusion and benefits the conversion of CO2. MOFs 1-2 exhibit good electrocatalytic activity for CO2RR in 0.5 M KHCO3 solution. Especially, the current density of MOF 2 generated at -0.90 V (vs. RHE) reaches -81.6 mA·cm-2, which is 3.1 times higher than that under an Ar atmosphere. In addition, MOFs 1-2 can be used as a heterogeneous catalyst for chemical conversion of CO2. The results are expected to provide inspiration for rational design to develop stable and high-efficiency MOF-based electrocatalysts for CO2RR.

4.
Mikrochim Acta ; 191(5): 239, 2024 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-38570399

RESUMEN

To accurately detect tumor marker carbohydrate antigen 72-4 (CA72-4) of serum samples is of great significance for the early diagnosis of malignant tumors. In the present study, MnO2/hollow nanobox metal-organic framework (HNM)-AuPtPd nanocomposites were prepared via multi-step synthesis and superposition method and a series of characterizations were carried out. A highly sensitive immunosensor Ab/MnO2/HNM-AuPtPd/GCE based on the composite nanomaterial was further prepared and used to detect the tumor marker CA72-4. The constructed immunosensor achieved signal amplification by increasing the electrocatalytic activity to H2O2 by means of the synergistic effect of MnO2 ultra-thin nanosheets (MnO2 UNs) and HNM-AuPtPd. At the same time, the electrochemical properties of the immunosensor were analyzed using cyclic voltammetry, electrochemical impedance, amperometry (with the test voltage of -0.4 V), and differential pulse voltammetry. The experimental results showed that the MnO2/HNM-AuPtPd nanocomposites were successfully prepared, and the immunosensor Ab/MnO2/HNM-AuPtPd/GCE demonstrated an excellent electrochemical performance. The electrochemical immunosensor had the highest detection sensitivity under the optimal experimental conditions, such as incubation pH of 7.0, incubation time of 60 min, with the addition of 15 µL of H2O2, and in the concentration range 0.001-500 U/mL. It had a low detection limit of 1.78×10-5 U/mL (S/N = 3). Moreover, the serum sample recovery were in the range from 99.38 to 100.52%. This study provides a new method and experimental basis for the detection of tumor markers in clinical practice.


Asunto(s)
Antígenos de Carbohidratos Asociados a Tumores , Técnicas Biosensibles , Nanocompuestos , Biomarcadores de Tumor , Técnicas Biosensibles/métodos , Peróxido de Hidrógeno/química , Compuestos de Manganeso/química , Óxidos/química , Inmunoensayo , Nanocompuestos/química
5.
Langmuir ; 39(17): 6258-6265, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37074756

RESUMEN

Various carcinogenic dyes in water bodies are difficult to degrade due to their stability to light and oxidants, causing extended pollution. In this study, MOF 1 ({[Co(tib)2]·(H2O)2·SO4}n) and MOF 2 ({[Cu(tib)2]·(H2O)2·SO4}n) (tib = 1,3,5-tirs(1-imidazolyl)benzene) were synthesized by the solvothermal method. MOFs 1 and 2 were successfully characterized by single-crystal X-ray diffraction (XRD) and powder X-ray diffraction (PXRD). Based on the structural characteristics of MOFs 1 and 2, we designed two cationic MOF material skeletons, namely, MOFs I and II ([Co(tib)22+]n and [Cu(tib)22+]n), which were obtained by calcination in combination with the thermogravimetric curve to remove the free components in the lattice. As expected, MOFs I and II showed an excellent adsorption effect on sulfonic anionic dyes. Notably, the adsorption capacity of MOF I can reach 2922.8 mg g-1 for Congo Red (CR) at room temperature (RT). The adsorption process fits the pseudo-second-order kinetic model and Freundlich isotherm model. Moreover, zeta potential tests and quantum chemical calculations indicate that electrostatic interactions and hydrogen bond between the hydroxyl group on the sulfonic acid group and the N atom on the imidazole ring mainly promote the adsorption of CR dyes on MOF I. MOFs I and II are revealed as a promising novel adsorption material to remove hazardous organic aromatic pollutants with high efficiency in future endeavors.

6.
Inorg Chem ; 62(16): 6339-6351, 2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-37045791

RESUMEN

Metal-organic frameworks (MOFs) have exhibited appreciable potential as catalytic agents in the field of material science. The research of new MOFs with dual functions in electrocatalysis and photocatalysis under ultraviolet (UV) irradiation is extremely pivotal for renewable energy applications. Hence, we synthesized a series of three-dimensional MOFs, namely, [Cd(bimb)2(HITA)2]n (Cd-MOF 1), {[Cd(bimb)6](NO3)2}n (Cd-MOF 2), and [Cd(bimb)4(ONO2)2]n (Cd-MOF 3) (bimb = 1,4-bis(imidazol-1-ylmethyl)benzene; H2ITA = 5-hydroxyisophthalic acid), with applicability in the oxygen evolution reaction process and Fenton-like photocatalysis. The obtained results show that Cd-MOF 1 exhibited the most remarkable catalytic performance, affording a current density of 10 mA cm-2 at a very low overpotential of 279 mV and the smallest Tafel slope of 85.13 mV dec-1. Meanwhile, these MOFs can generate hydroxyl radicals (•OH) under UV light irradiation with the existence of H2O2, enabling the rapid degradation of organic pollutants. This study provides a valuable direction for producing multifunctional and environmentally friendly catalysts.

7.
Int J Mol Sci ; 24(3)2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36768304

RESUMEN

Dental plaque, a complex biofilm system established by cariogenic bacteria such as Streptococcus mutans (S. mutans), is the initiator of dental caries. Studies have found that the cell-free supernatant (CFS) of Lactobacilli could inhibit S. mutans biofilm formation. However, the main antibiofilm substance of the Lactobacilli CFS that acts against S. mutans is unclear. The present study found that the CFS of Lactobacillus plantarum (L. plantarum) ATCC 14917 had the strongest antibiofilm effect among the five tested oral Lactobacilli. Further bioassay-guided isolation was performed to identify the main antibiofilm substance. The antibiofilm effect of the end product, named 1-1-4-3, was observed and the structure of it was elucidated by using Q-TOF MS, 2D NMR and HPLC. The results showed that several components in the CFS had an antibiofilm effect; however, the effect of 1-1-4-3 was the strongest, as it could reduce the generation of exopolysaccharides and make the biofilm looser and thinner. After structure elucidation and validation, 1-1-4-3 was identified as a mixture of lactic acid (LA) and valine. Additionally, LA was shown to be the main antibiofilm substance in 1-1-4-3. In summary, this study found that the antibiofilm effect of the L. plantarum CFS against S. mutans was attributable to the comprehensive effect of multiple components, among which LA played a dominant role.


Asunto(s)
Caries Dental , Lactobacillus plantarum , Humanos , Streptococcus mutans , Caries Dental/prevención & control , Lactobacillus , Biopelículas
8.
J Org Chem ; 87(1): 835-845, 2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34962788

RESUMEN

An efficient method for the synthesis of new indolizine-fused chromones has been accomplished from ethyl (E)-3-(2-acetylphenoxy)acrylates and pyridines in a "one-pot" manner. Facile operation in open-air, metal-free, and mild conditions renders this protocol particularly practical and attractive. Moreover, this method can simultaneously construct two molecular fragments of chromone and indolizine. Scale-up experiment and the construction of natural products further prove the practicability of this strategy.


Asunto(s)
Indolizinas , Yodo , Cromonas , Ciclización , Piridinas
9.
J Org Chem ; 86(21): 15733-15742, 2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34633821

RESUMEN

An iodine-promoted one-pot cascade oxidative annulation reaction has been developed for the synthesis of chromone-fused-pyrrolo[2,1-a]isoquinolines and indolizino[8,7-b]indoles from o-acetylphenoxyacrylates, tetrahydroisoquinolines, and noreleagnines. This process underwent a logical approach to both chromone-fused-pyrrolo[2,1-a]isoquinolines and chromone-fused-indolizino[8,7-b]indoles isolamellarin derivatives. Manipulations of l-menthol and dl-α-tocopherol demonstrate the applications of this strategy.

10.
J Org Chem ; 86(23): 17471-17481, 2021 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-34797656

RESUMEN

A highly chemoselective cascade Wolff rearrangement/acylation reaction between 5-aminopyrazoles and diazo compounds has been developed. The protocol can facilitate the switchable synthesis of 4-hydroxy-pyrazolo[3,4-b]pyridin-6-ones and N-pyrazole amides with the merits of a broad substrate scope, high functional group compatibility, and green and sustainable performance manner. All reactions proceeded efficiently without any catalyst and additives (acid and base) and resulted in the release of benign N2, wherein diethyl carbonate served as a green benign solvent.


Asunto(s)
Amidas , Pirazoles , Acilación , Estructura Molecular
11.
Appl Microbiol Biotechnol ; 104(22): 9733-9748, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33064184

RESUMEN

Bacterial membrane vesicles (MVs) are used as a tool for intercellular communication and seem essential for bacterial survival. However, few data are available on MVs generated by Streptococcus mutans, which is the main aetiological agent of dental caries. The present study presents an integrated proteomics and metabolomics analysis of MVs isolated from S. mutans at initial pH values of 7.5 and 5.5 and explores their function. The results showed that S. mutans releases more MVs with smaller diameters under acidic conditions than under neutral conditions. Proteomic analysis showed 344 common vesicular proteins, including various virulence factors. The expressions of 140 individual proteins and 37 metabolites were altered as a result of culturing S. mutans at different pH values. Co-analyses of proteomic and metabolomics data indicated that ABC transporters underwent significant changes under acid pressure. We concluded that S. mutans produced MVs at different pH values to carry proteins associated with cariogenesis. Moreover, the alterations of S. mutans MVs under acid pressure were associated with ABC transporters. These results increase our knowledge of S. mutans MVs and imply that S. mutans MVs may play a functional role in carious infection. KEY POINTS: • S. mutans MVs contained virulence factor-related proteins, even at low pH values. • Integrated proteomics and metabolomics analysis showed that S. mutans MVs alterations under acidic conditions were associated with ABC transporters.


Asunto(s)
Caries Dental , Proteómica , Streptococcus mutans , Proteínas Bacterianas , Biopelículas , Humanos , Concentración de Iones de Hidrógeno
12.
Nanotechnology ; 28(8): 084001, 2017 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-27981955

RESUMEN

MoO2 is used as a new source material for the growth of large area and high optical quality monolayer MoS2. However, a systematic study of the growth parameters is still missing and large-area growth of discreet single crystals is still challenging. Hereby, we report the shape evolution of monolayer growth of MoS2 and develop a methodology to achieve centimeter-scaled discrete MoS2 by adopting MoO2 as Mo source material in an atmospheric-pressure chemical vapor deposition process. Our results indicate the growth of monolayer MoS2 could benefit from the precise control of the introduction time of sulfur and the S/MoO2 ratio in experiments. Micro-Raman and photoluminescence spectra confirm the properties of the material. E-beam lithography was utilized to make contact with the as-grown MoS2 located at the selective area. The electrical properties of MoS2 with different morphologies were compared. In the end, the persistent photoconductivity properties of monolayer MoS2 were emphasized and the underlying mechanism was proposed. These studies demonstrate a better understanding of the growth and application of MoS2-based 2D materials.

13.
Nanotechnology ; 28(32): 325602, 2017 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-28718451

RESUMEN

Transition metal dichalcogenides (TMDs) have attracted considerable interest for exploration of next-generation electronics and optoelectronics in recent years. Fabrication of in-plane lateral heterostructures between TMDs has opened up excellent opportunities for engineering two-dimensional materials. The creation of high quality heterostructures with a facile method is highly desirable but it still remains challenging. In this work, we demonstrate a one-step growth method for the construction of high-quality MoS2-WS2 in-plane heterostructures. The synthesis was carried out using ambient pressure chemical vapor deposition (APCVD) with the assistance of sodium chloride (NaCl). It was found that the addition of NaCl played a key role in lowering the growth temperatures, in which the Na-containing precursors could be formed and condensed on the substrates to reduce the energy of the reaction. As a result, the growth regimes of MoS2 and WS2 are better matched, leading to the formation of in-plane heterostructures in a single step. The heterostructures were proved to be of high quality with a sharp and clear interface. This newly developed strategy with the assistance of NaCl is promising for synthesizing other TMDs and their heterostructures.

14.
PLoS One ; 19(3): e0298684, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38451911

RESUMEN

Accurate bike-sharing demand prediction is crucial for bike allocation rebalancing and station planning. In bike-sharing systems, the bike borrowing and returning behavior exhibit strong spatio-temporal characteristics. Meanwhile, the bike-sharing demand is affected by the arbitrariness of user behavior, which makes the distribution of bikes unbalanced. These bring great challenges to bike-sharing demand prediction. In this study, a usage pattern similarity-based dual-network for bike-sharing demand prediction, called FF-STGCN, is proposed. Inter-station flow features and similar usage pattern features are fully considered. The model includes three modules: multi-scale spatio-temporal feature fusion module, bike usage pattern similarity learning module, and bike-sharing demand prediction module. In particular, we design a multi-scale spatio-temporal feature fusion module to address limitations in multi-scale spatio-temporal accuracy. Then, a bike usage pattern similarity learning module is constructed to capture the underlying correlated features among stations. Finally, we employ a dual network structure to integrate inter-station flow features and similar usage pattern features in the bike-sharing demand prediction module to realize the final prediction. Experiments on the Citi Bike dataset have demonstrated the effectiveness of our proposed model. The ablation experiments further confirm the indispensability of each module in the proposed model.


Asunto(s)
Ciclismo , Transportes , Aprendizaje , Pirimetamina
15.
Bioelectrochemistry ; 160: 108755, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38878457

RESUMEN

Cancer antigen 72-4 (CA72-4) is an important marker of cancer detection, and accurate detection of CA72-4 is urgently required. Herein, a sandwich-type immunosensor was constructed for detection CA72-4 based on composite nanomaterial as the substrate material and trimetal nanoparticles as the nanoprobe. The composite nanomaterial rGO-TEPA/ZIF67@ZIF8/Au used as a selective bio-recognition element were modified on the glassy carbon electrode (GCE) surface. Meanwhile, the electrochemical nanoprobes were fabricated through the AuPdRu trimeric metal. After the target antigen 72-4 were captured, the nanoprobes were further assembled to form an antibody1 (Ab1)- antigen-antibody2 (Ab2) nanoprobes sandwich-like system on the electrode surface. Then, hybrid the substrate material rGO-TEPA/ZIF67@ZIF8/Au and the AuPdRu trimeric metal nanoprobes efficiently catalyzed the reduction of H2O2 and amplified the electrochemical signals. Cyclic voltammetry (CV), differential pulse voltammetry (DPV), electrochemical impedance spectroscopy (EIS), and Chronoamperometry (I-T) methods were used to characterize the performance and detection capabilities for CA72-4 of the prepared immunosensors. The results showed that the detection limit was 1.8 × 10-5 U/mL (S/N = 3), and the linear range was 0.001-1000 U/mL. This study provides a new signal amplification strategy for electrochemical sensors and a theoretical basis for the clinical application of immunosensor to detect other tumor markers.

16.
Environ Sci Pollut Res Int ; 31(11): 17401-17416, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38337115

RESUMEN

In recent years, experts and academics in the environmental management field have developed an interest in the factors and evaluation techniques that influence corporate environmental investment decisions. However, there are substantial differences between studies employing the most recent evaluation methodologies and those that use indicator systems. To explore the mechanisms that influence corporate environmental investment, this study investigated the determinants of environmental investment through the perspectives of firm, board, chair, and chief executive officer (CEO) characteristics using a machine learning approach. Based on a large-scale data sample from Chinese-listed companies, the results indicated that the extreme gradient boosting (XGBoost) model had an accuracy of up to 97.63%, thus performing the best. Additionally, the model that used SHapley Additive exPlanations (SHAP) to interpret XGBoost showed that a company's sales performance was the most important factor that influenced environmental investment, followed by CEO tenure, board independence, board gender diversity, chair academic experience, and the company's level of internationalization. Furthermore, when examining the sample of heavily polluting enterprises, sales, board gender diversity, CEO tenure, chair academic experience, board independence, and chair-CEO duality, all were found to play crucial roles in predicting environmental investment. Overall, this study aids in evaluating the factors that influence corporate environmental investment decisions and provides policymakers and practitioners with a machine learning approach for use when assessing these factors.


Asunto(s)
Comercio , Inversiones en Salud , Aprendizaje Automático
17.
Brain Sci ; 13(4)2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37190661

RESUMEN

Grammatical gender as a lexico-syntactic feature has been well explored, and the gender congruency effect has been observed in many languages (e.g., Dutch, German, Croatian, Czech, etc.). Yet, so far, this effect has not been found in Romance languages such as Italian, French, and Spanish. It has been argued that the absence of the effect in Romance languages is due the fact that the gender-marking definite article is not exclusively dependent on the grammatical gender of the head noun, but also on its onset phonology (e.g., lo zucchero is 'the sugar' in Italian, not il zucchero, il being the default masculine determiner in Italian). For Spanish, this argument has also been made because feminine words starting with a stressed /a/ take the masculine article (e.g., el água is 'the water', not la água). However, the number of words belonging to that set is rather small in Spanish, and it may be questionable whether or not this feature can be taken as an argument for the absence of a gender congruency effect in Spanish. In this study, we investigated the gender congruency effect in native Spanish noun phrase production. We measured 30 native Spanish speakers' naming latencies in four conditions via the picture-word interference paradigm by manipulating gender congruency (i.e., gender-congruent vs. gender-incongruent) and semantic relatedness (i.e., semantically related vs. semantically unrelated). The results revealed significantly longer naming latencies in gender-incongruent and semantically related conditions compared to gender-congruent and semantically unrelated conditions. This result suggests that grammatical gender as a lexico-syntactic feature in Spanish is used to competitively select determiners in native Spanish speakers' noun phrases. Our findings provide an important behavioral piece of evidence for the gender congruency effect in Romance languages.

18.
Talanta ; 265: 124803, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37331043

RESUMEN

Three novel Co-based coordination polymers including {[Co(L)(µ3-O)1/3]2}n (1), {[Co(L)(bimb)]}n (2) and {[Co(L)(bimmb)1/2]}n (3) (H2L = 2,6-di(4-carboxylphenyl)-4-(4-(triazol-1-ylphenyl))pyridine), bimb = 1,4-bis(lmidazol) butane, bimmb = 1,4-bis(imidazole-1-ylmethyl)benzene) were successfully prepared under solvothermal conditions and characterized. Single-crystal X-ray diffraction analyses revealed that 1 possesses a 3D architecture composed of a trinuclear cluster [Co3N3(CO2)6(µ3-O)], 2 exhibits a 2D new topological framework with the point symbol (84·122)(8)2, whereas 3 shows a unique six-fold interpenetrated 3D framework with a (63·82·10)2(63)2(8) topology. Impressively, all of them can function as a highly selective and sensitive fluorescent sensor for the biomarker methylmalonic acid (MMA) via fluorescence quenching. The low detection limit, reusability and high anti-interference performance together make 1-3 become promising sensors for the practical detection of MMA. Furthermore, the successful application of MMA detection in urine sample was demonstrated, which may be a potential candidate for the further development of clinical diagnostic tools.


Asunto(s)
Benceno , Ácido Metilmalónico , Biomarcadores , Colorantes , Polímeros
19.
AMB Express ; 12(1): 154, 2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36508003

RESUMEN

Streptococcus mutans, whose main virulence factor is glucosyltransferase (Gtf), has a substantial impact on the development of dental caries. S. mutans membrane vesicles (MVs), which are rich in Gtfs, have been shown to affect biofilm formation of other microorganisms. Streptococcus gordonii and Streptococcus sanguinis are initial colonizers of tooth surfaces, which provide attachment sites for subsequent microorganisms and are crucial in the development of oral biofilms. S. mutans and S. gordonii, as well as S. mutans and S. sanguinis, have a complex competitive and cooperative relationship, but it is unclear whether S. mutans MVs play a role in these interspecific interactions. Therefore, we co-cultured S. mutans MVs, having or lacking Gtfs, with S. gordonii and S. sanguinis. Our results showed that S. mutans MVs inhibited biofilm formation of S. gordonii and S. sanguinis but did not affect their planktonic growth; contrastingly, S. mutans ΔgtfBC mutant MVs had little effect on both their growth and biofilm formation. Additionally, there were fewer and more dispersed bacteria in the biofilms of the S. mutans MV-treated group than that in the control group. Furthermore, the expression levels of the biofilm-related virulence factors GtfG, GtfP, and SpxB in S. gordonii and S. sanguinis were significantly downregulated in response to S. mutans MVs. In conclusion, the results of our study showed that S. mutans MVs inhibited biofilm formation of S. gordonii and S. sanguinis, revealing an important role for MVs in interspecific interactions.

20.
Front Cell Infect Microbiol ; 12: 940602, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35959374

RESUMEN

Streptococcus mutans and Candida albicans, as the most common bacterium and fungus in the oral cavity respectively, are considered microbiological risk markers of early childhood caries. S. mutans membrane vesicles (MVs) contain virulence proteins, which play roles in biofilm formation and disease progression. Our previous research found that S. mutans MVs harboring glucosyltransferases augment C. albicans biofilm formation by increasing exopolysaccharide production, but the specific impact of S. mutans MVs on C. albicans virulence and pathogenicity is still unknown. In the present study, we developed C. albicans biofilms on the surface of cover glass, hydroxyapatite discs and bovine dentin specimens. The results showed that C. albicans can better adhere to the tooth surface with the effect of S. mutans MVs. Meanwhile, we employed C. albicans biofilm-bovine dentin model to evaluate the influence of S. mutans MVs on C. albicans biofilm cariogenicity. In the S. mutans MV-treated group, the bovine dentin surface hardness loss was significantly increased and the surface morphology showed more dentin tubule exposure and broken dentin tubules. Subsequently, integrative proteomic and metabolomic approaches were used to identify the differentially expressed proteins and metabolites of C. albicans when cocultured with S. mutans MVs. The combination of proteomics and metabolomics analysis indicated that significantly regulated proteins and metabolites were involved in amino acid and carbohydrate metabolism. In summary, the results of the present study proved that S. mutans MVs increase bovine dentin demineralization provoked by C. albicans biofilms and enhance the protein and metabolite expression of C. albicans related to carbohydrate metabolism.


Asunto(s)
Caries Dental , Streptococcus mutans , Animales , Biopelículas , Candida albicans , Metabolismo de los Hidratos de Carbono , Bovinos , Preescolar , Humanos , Proteómica , Virulencia
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