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1.
J Colloid Interface Sci ; 677(Pt A): 718-728, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39121656

RESUMO

In the last decades, 4-nitrophenol is regarded as one of highly toxic organic pollutants in industrial wastewater, which attracts great concern to earth sustainability. Herein, atomically dispersed ternary FeCoNb active sites were incorporated into nitrogen-doped honeycomb-like mesoporous carbon (termed FeCoNb/NHC) by a two-step pyrolysis strategy, whose morphology, structure and size were characterized by a set of techniques. Further, the catalytic activity and reusability of the as-prepared FeCoNb/NHC were rigorously examined by using 4-NP catalytic hydrogenation as a proof-of-concept model. The influence of the secondary pyrolysis temperature on the catalytic performance was investigated, combined by illuminating the catalytic mechanism. The resultant catalyst exhibited significantly enhanced catalytic features with a normalized rate constant (kapp) of 1.2 × 104 min-1g-1 and superior stability, surpassing the home-made catalysts in the control groups and earlier research. This study provides some constructive insights for preparation of high-efficiency and cost-effectiveness single-atom nanocatalysts in organic pollutants environmental remediation.

2.
J Colloid Interface Sci ; 677(Pt B): 221-231, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39142162

RESUMO

Facile synthesis of high-efficiency and stable bifunctional electrocatalyst is essential for producing clean hydrogen in energy storage systems. Herein, low Rh-doped flower-like Ni3S2/Co3S4 heterostructures were facilely prepared on porous nickel foam (labeled Rh-Ni3S2/Co3S4/NF) by a hydrothermal method. The correlation of the precursors types with the morphological structures and catalytic properties were rigorously investigated for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in the control groups. The low Rh doping within the catalyst played important role in boosting the catalytic characteristics. The resulting catalyst showed the smaller overpotentials of 197 and 78 mV to drive a current density of 10 mA cm-2 for the OER and HER in alkaline electrolyte, respectively. And the potential only required 1.71 V to drive a current density of 100 mA cm-2 in a water splitting device. It reflects excellent overall water splitting of the home-made Rh-Ni3S2/Co3S4/NF. This strategy shed some constructive light for preparing transition metal sulfide-based electrocatalysts in water splitting devices.

3.
Nat Nanotechnol ; 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39179796

RESUMO

Lipid nanoparticle (LNP)-mRNA complexes are transforming medicine. However, the medical applications of LNPs are limited by their low endosomal disruption rates, high toxicity and long tissue persistence times. LNPs that rapidly hydrolyse in endosomes (RD-LNPs) could solve the problems limiting LNP-based therapeutics and dramatically expand their applications but have been challenging to synthesize. Here we present an acid-degradable linker termed 'azido-acetal' that hydrolyses in endosomes within minutes and enables the production of RD-LNPs. Acid-degradable lipids composed of polyethylene glycol lipids, anionic lipids and cationic lipids were synthesized with the azido-acetal linker and used to generate RD-LNPs, which significantly improved the performance of LNP-mRNA complexes in vitro and in vivo. Collectively, RD-LNPs delivered mRNA more efficiently to the liver, lung, spleen and brains of mice and to haematopoietic stem and progenitor cells in vitro than conventional LNPs. These experiments demonstrate that engineering LNP hydrolysis rates in vivo has great potential for expanding the medical applications of LNPs.

4.
Nat Protoc ; 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39174659

RESUMO

The production of living therapeutics, cell-based delivery of drugs and gene-editing tools and the manufacturing of bio-commodities all share a common concept: they use either a synthetic or a living cell chassis to achieve their primary engineering or therapeutic goal. Live-cell chassis face limitations inherent to their auto-replicative nature and the complexity of the cellular context. This limitation highlights the need for a new chassis combining the engineering simplicity of synthetic materials and the functionalities of natural cells. Here, we describe a protocol to assemble a synthetic polymeric network inside bacterial cells, rendering them incapable of cell division and allowing them to resist environmental stressors such as high pH, hydrogen peroxide and cell-wall-targeting antibiotics that would otherwise kill unmodified bacteria. This cellular bioengineering protocol details how bacteria can be transformed into single-lifespan devices that are resistant to environmental stressors and possess programable functionality. We designate the modified bacteria as cyborg bacterial cells. This protocol expands the synthetic biology toolset, conferring precise control over living cells and creating a versatile cell chassis for biotechnology, biomedical engineering and living therapeutics. The protocol, including the preparation of gelation reagents and chassis strain, can be completed in 4 d. The implementation of the protocol requires expertise in microbiology techniques, hydrogel chemistry, fluorescence microscopy and flow cytometry. Further functionalization of the cyborg bacterial cells and adaptation of the protocol requires skills ranging from synthetic genetic circuit engineering to hydrogel polymerization chemistries.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38955871

RESUMO

Previous research has indicated that the left dorsolateral prefrontal cortex (DLPFC) exerts an influence on attentional bias toward visual emotional information. However, it remains unclear whether the left DLPFC also play an important role in attentional bias toward natural emotional sounds. The current research employed the emotional spatial cueing paradigm, incorporating natural emotional sounds of considerable ecological validity as auditory cues. Additionally, high-definition transcranial direct current stimulation (HD-tDCS) was utilized to examine the impact of left dorsolateral prefrontal cortex (DLPFC) on attentional bias and its subcomponents, namely attentional engagement and attentional disengagement. The results showed that (1) compared to sham condition, anodal HD-tDCS over the left DLPFC reduced the attentional bias toward positive and negative sounds; (2) anodal HD-tDCS over the left DLPFC reduced the attentional engagement toward positive and negative sounds, whereas it did not affect attentional disengagement away from natural emotional sounds. Taken together, the present study has shown that left DLPFC, which was closely related with the top-down attention regulatory function, plays an important role in auditory emotional attentional bias.

6.
Small ; : e2402104, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949416

RESUMO

To meet increasing requirement for innovative energy storage and conversion technology, it is urgent to prepare effective, affordable, and long-term stable oxygen electrocatalysts to replace precious metal-based counterparts. Herein, a two-step pyrolysis strategy is developed for controlled synthesis of Fe2O3 and Mn3O4 anchored on carbon nanotubes/nanosheets (Fe2O3-Mn3O4-CNTs/NSs). The typical catalyst has a high half-wave potential (E1/2 = 0.87 V) for oxygen reduction reaction (ORR), accompanied with a smaller overpotential (η10 = 290 mV) for oxygen evolution reaction (OER), showing substantial improvement in the ORR and OER performances. As well, density functional theory calculations are performed to illustrate the catalytic mechanism, where the in situ generated Fe2O3 directly correlates to the reduced energy barrier, rather than Mn3O4. The Fe2O3-Mn3O4-CNTs/NSs-based Zn-air battery exhibits a high-power density (153 mW cm-2) and satisfyingly long durability (1650 charge/discharge cycles/550 h). This work provides a new reference for preparation of highly reversible oxygen conversion catalysts.

7.
Front Psychol ; 15: 1417557, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39035086

RESUMO

Introduction: Representations in working memory can affect distractor suppression in human visual search, and this process is modulated by a separate top-down cognitive control. An increasing body of research has demonstrated that patients with substance use disorder (SUD) have deficits in cognitive control over filtering interference by perceptual distractors. However, their ability to resist proactive interference from working memory has received comparatively less attention. Methods: Here, we investigate this issue by employing a working memory/visual search dual-task paradigm. An intervening gap-location search task was instructed to be performed while participants memorized a written color word, with congruent auditory information present during the memory encoding phase on half of the trials. Results: Results showed that there was a reliable response time (RT) advantage when the meaning of the memory sample agreed with the color of one of the distractors under the visual alone condition. However, such a result was only found in the control group. More importantly, both groups exhibited comparable facilitation under the audiovisual condition, with the facilitation effect appearing later in the SUD group. Furthermore, the facilitation effect was superior in magnitude and time course under the audiovisual condition to the visual alone condition. Discussion: These findings highlight how patients with SUD resist distractor interference at the memory level and extend our understanding of how working memory, selective attention, and audiovisual enhancement interact to optimize perceptual decisions in patients with SUD.

8.
Memory ; 32(8): 1069-1082, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39067050

RESUMO

Converging evidence suggests a facilitation effect of multisensory interactions on memory performance, reflected in higher accuracy or faster response time under a bimodal encoding condition than a unimodal condition. However, relatively little attention has been given to the effect of multisensory competition on memory. The present study adopted an adaptive staircase test to measure the point of subjective simultaneity (PSS), combined with a delayed matched-to-sample (DMS) task to probe the effect of audiovisual competition during the encoding stage on subsequent unisensory retrieval. The results showed that there was a robust visual dominance effect and multisensory interference effect in WM retrieval, regardless of the subjective synchronous or subjective asynchronous audiovisual presentation. However, a weakened visual dominance effect was observed when the auditory stimulus was presented before the visual stimulus in the encoding period, particularly in the semantically incongruent case. These findings revealed that the prior-entry of sensory information in the early perceptual stage could affect the processing in the late cognitive stage to some extent, and supported the evidence that there is a persistent advantage for visuospatial sketchpad in multisensory WM.


Assuntos
Estimulação Acústica , Percepção Auditiva , Memória de Curto Prazo , Rememoração Mental , Estimulação Luminosa , Tempo de Reação , Percepção Visual , Humanos , Percepção Visual/fisiologia , Feminino , Masculino , Memória de Curto Prazo/fisiologia , Percepção Auditiva/fisiologia , Adulto Jovem , Tempo de Reação/fisiologia , Rememoração Mental/fisiologia , Adulto , Atenção/fisiologia
9.
Macromol Biosci ; : e2400194, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39073313

RESUMO

Surface modification plays a crucial role in enhancing the functionality of implanted interventional medical devices, offering added advantages to patients, particularly in terms of lubrication and prevention of undesired adsorption of biomolecules and microorganisms, such as proteins and bacteria, on the material surfaces. Utilizing polymer brushes for surface modification is currently a promising approach to maintaining the inherent properties of materials while introducing new functionalities to surfaces. Here, surface-initiated atom transfer radical polymerization (SI-ATRP) technology to effectively graft anionic, cationic, and neutral polymer brushes from a mixed silane initiating layer is employed. The presence of a polymer brush layer significantly enhances the lubrication performance of the substrates and ensures a consistently low coefficient of friction over thousands of friction cycles in aqueous environments. The antimicrobial efficacy of polymer brushes is evaluated against gram-positive Staphylococcus aureus (S. aureus) and gram-negative Escherichia coli (E. coli). It is observed that polym er brushes grafted to diverse substrate surfaces displays notable antibacterial properties, effectively inhibiting bacterial attachment. Furthermore, the polymer brush layer shows favorable biocompatibility and anti-inflammatory characteristics, which shows potential applications in dental materials, and other fields such as catheters and food packaging.

10.
Bioengineering (Basel) ; 11(6)2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38927855

RESUMO

Biophysical factors play a fundamental role in human embryonic development. Traditional in vitro models of organogenesis focused on the biochemical environment and did not consider the effects of mechanical forces on developing tissue. While most human tissue has a Young's modulus in the low kilopascal range, the standard cell culture substrate, plasma-treated polystyrene, has a Young's modulus of 3 gigapascals, making it 10,000-100,000 times stiffer than native tissues. Modern in vitro approaches attempt to recapitulate the biophysical niche of native organs and have yielded more clinically relevant models of human tissues. Since Clevers' conception of intestinal organoids in 2009, the field has expanded rapidly, generating stem-cell derived structures, which are transcriptionally similar to fetal tissues, for nearly every organ system in the human body. For this reason, we conjecture that organoids will make their first clinical impact in fetal regenerative medicine as the structures generated ex vivo will better match native fetal tissues. Moreover, autologously sourced transplanted tissues would be able to grow with the developing embryo in a dynamic, fetal environment. As organoid technologies evolve, the resultant tissues will approach the structure and function of adult human organs and may help bridge the gap between preclinical drug candidates and clinically approved therapeutics. In this review, we discuss roles of tissue stiffness, viscoelasticity, and shear forces in organ formation and disease development, suggesting that these physical parameters should be further integrated into organoid models to improve their physiological relevance and therapeutic applicability. It also points to the mechanotransductive Hippo-YAP/TAZ signaling pathway as a key player in the interplay between extracellular matrix stiffness, cellular mechanics, and biochemical pathways. We conclude by highlighting how frontiers in physics can be applied to biology, for example, how quantum entanglement may be applied to better predict spontaneous DNA mutations. In the future, contemporary physical theories may be leveraged to better understand seemingly stochastic events during organogenesis.

11.
Talanta ; 278: 126464, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38936106

RESUMO

Deoxynivalenol (DON), a mycotoxin produced by Fusarium, poses a significant risk to human health and the environment. Therefore, the development of a highly sensitive and accurate detection method is essential to monitor the pollution situation. In response to this imperative, we have devised an advanced split-type photoelectrochemical (PEC) sensor for DON analysis, which leverages self-shedding MOF-nanocarriers to modulate the photoelectric response ability of PEC substrate. The PEC sensing interface was constructed using CdS/MoSe2 heterostructures, while the self-shedding copper peroxide nanodots@ZIF-8 (CPNs@ZIF-8) served as the Cu2+ source for the in-situ ion exchange reaction, which generated a target-related signal reduction. The constructed PEC sensor exhibited a broad linear range of 0.1 pg mL-1 to 500 ng mL-1 with a low detection limit of 0.038 pg mL-1, demonstrating high stability, selectivity, and proactivity. This work not only introduces innovative ideas for the design of photosensitive materials, but also presents novel sensing strategies for detecting various environmental pollutants.


Assuntos
Compostos de Cádmio , Técnicas Eletroquímicas , Estruturas Metalorgânicas , Tricotecenos , Tricotecenos/análise , Tricotecenos/química , Técnicas Eletroquímicas/métodos , Compostos de Cádmio/química , Estruturas Metalorgânicas/química , Sulfetos/química , Limite de Detecção , Processos Fotoquímicos , Troca Iônica
12.
Int Med Case Rep J ; 17: 597-602, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38895178

RESUMO

Introduction: This study presents a rare case of multiple evanescent white dot syndrome (MEWDS) with atypical electrooculogram (EOG) findings, as well as abnormal en-face images of minimum intensity projection (Min-IP) and the en-face inner segment/outer segment-ellipsoid complex. Methods: A 25-year-old female patient presented with painless visual impairment and photopsia in her right eye for a duration of two days. Multimodal imaging was employed including color fundus photography (CFP), fundus autofluorescence (FAF), spectral-domain optical coherence tomography (SD-OCT), and optical coherence tomography angiography (OCTA), and en-face images of Min-IP and the en-face inner segment/outer segment-ellipsoid complex were performed. Results: In the right eye, multifocal small white spots were observed surrounding the posterior pole and optic disc of retina with the granular appearance of the fovea. FAF displayed of hyperfluorescence. SD-OCT appearance of MEWDS demonstrated primarily disrupted ellipsoid zone (EZ), photoreceptor outer segments, and interdigitation zone (IZ) complex within the fovea. The en-face images of the inner segment/outer segment-ellipsoid complex and Min-IP exhibited hyperreflective spots in the right eye. In the left eye, interestingly, hyperreflective spots were also observed on the en-face image of the inner segment/outer segment-ellipsoid complex. EOG revealed an Arden ratio of 2.5 for the right eye, while the left eye exhibited an Arden ratio of 1.7. Conclusion: The en-face image of the inner segment/outer segment-ellipsoid complex in MEWDS exhibits aberrant features and it is noteworthy that a similar alteration may occur in the fellow eye. Further investigation is required to explore the relationship between MEWDS and EOG. The en-face images of the inner segment/outer segment-ellipsoid complex and Min-IP may help to elucidate the pathogenesis of MEWDS.

13.
Biomater Adv ; 162: 213919, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38861801

RESUMO

Tumor microenvironment (TME)-responsive chemodynamic therapy (CDT) is severely hindered by insufficient intracellular H2O2 level that seriously deteriorates antitumor efficacy, albeit with its extensively experimental and theoretical research. Herein, we designed atomically dispersed FeCo dual active sites anchored in porous carbon polyhedra (termed FeCo/PCP), followed by loading with glucose oxidase (GOx) and anticancer doxorubicin (DOX), named FeCo/PCP-GOx-DOX, which converted glucose into toxic hydroxyl radicals. The loaded GOx can either decompose glucose to self-supply H2O2 or provide fewer nutrients to feed the tumor cells. The as-prepared nanozyme exhibited the enhanced in vitro cytotoxicity at high glucose by contrast with those at less or even free of glucose, suggesting sufficient accumulation of H2O2 and continual transformation to OH for CDT. Besides, the FeCo/PCP-GOx-DOX can subtly integrate starvation therapy, the FeCo/PCP-initiated CDT, and DOX-inducible chemotherapy (CT), greatly enhancing the therapeutic efficacy than each monotherapy.


Assuntos
Doxorrubicina , Glucose Oxidase , Peróxido de Hidrogênio , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/química , Doxorrubicina/farmacologia , Doxorrubicina/química , Doxorrubicina/uso terapêutico , Glucose Oxidase/metabolismo , Glucose Oxidase/química , Humanos , Animais , Microambiente Tumoral/efeitos dos fármacos , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Glucose/metabolismo , Domínio Catalítico
14.
Brain Sci ; 14(6)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38928551

RESUMO

Restrictive dieters are those who expect to achieve body shape and weight control through dieting. However, they often have difficulty suppressing the desire to consume food when confronted with it. It has been shown that when high- and low-calorie foods are presented together, the attention of restrictive eaters is preferentially directed to high-calorie foods. However, whether attentional bias occurs when low-calorie foods are present alone and whether the allocation of attentional resources is consistent with that for high-calorie foods has yet to be explored. The present study focused on the effects of high-/low-calorie foods on attentional bias in restrictive dieters. Seventy-eight participants were recruited to participate in the experiment via the Dutch Eating Behavior Questionnaire (DEBQ) scale, which is administered in a rapid serial visual presentation (RSVP) task. The results revealed that failed restrictive dieters had the lowest percentage of correct answers at the lag2 level, indicating attentional bias. Failed restrictive dieters allocated more attentional resources to high-calorie foods than to low-calorie foods. Restrictive dieters showed no attentional bias when low-calorie foods were presented alone. The results suggest that low-calorie foods do not elicit an attentional bias in restrictive dieters and that the allocation of attentional resources is not consistent when compared to that for high-calorie foods.

15.
Small ; : e2402981, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38838089

RESUMO

To address the imperative challenge of producing hydrogen in a low-energy consumption electrocatalytic system, this study emphasizes the utilization of thermodynamically favorable biomass oxidation for achieving energy-efficient hydrogen generation. This research integrates ultralow PtO2-loaded flower-like nanosheets (denoted as PtO2@Cu2O/Cu FNs) with Cu0/Cu+ pairs and Pt─O bonds, thereby yielding substantial enhancement in both hydrogen evolution reaction (HER, -0.042 VRHE at 10 mA cm-2) and furfural oxidation reaction (FFOR, 0.09 VRHE at 10 mA cm-2). As validated by DFT calculations, the dual built-in electric field (BIEF) is elucidated as the driving force behind the enhanced activities, in which Pt─O bonds expedite the HER, while Cu+/Cu0 promotes low-potential FFOR. By coupling the FFOR and HER together, the resulting bipolar-hydrogen production system requires a low power input (0.5072 kWh per m3) for producing H2. The system can generate bipolar hydrogen and high value-added furoic acid, significantly enhancing hydrogen production efficiency and concurrently mitigating energy consumption.

16.
Angew Chem Int Ed Engl ; 63(33): e202407748, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38818639

RESUMO

Selective producing ethanol from CO2 electroreduction is highly demanded, yet the competing ethylene generation route is commonly more thermodynamically preferred. Herein, we reported an efficient CO2-to-ethanol conversion (53.5 % faradaic efficiency at -0.75 V versus reversible hydrogen electrode (vs. RHE)) over an oxide-derived nanocubic catalyst featured with abundant "embossment-like" structured grain-boundaries. The catalyst also attains a 23.2 % energy efficiency to ethanol within a flow cell reactor. In situ spectroscopy and electrochemical analysis identified that these dualphase Cu(I) and Cu(0) sites stabilized by grain-boundaries are very robust over the operating potential window, which maintains a high concentration of co-adsorbed *CO and hydroxyl (*OH) species. Theoretical calculations revealed that the presence of *OHad not only promote the easier dimerization of *CO to form *OCCO (ΔG~0.20 eV) at low overpotentials but also preferentially favor the key *CHCOH intermediate hydrogenation to *CHCHOH (ethanol pathway) while suppressing its dehydration to *CCH (ethylene pathway), which is believed to determine the remarkable ethanol selectivity. Such imperative intermediates associated with the bifurcation pathway were directly distinguished by isotope labelling in situ infrared spectroscopy. Our work promotes the understanding of bifurcating mechanism of CO2ER-to-hydrocarbons more deeply, providing a feasible strategy for the design of efficient ethanol-targeted catalysts.

17.
Anal Chem ; 96(21): 8586-8593, 2024 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-38728058

RESUMO

Nowadays, signal enhancement is imperative to increase sensitivity of advanced ECL devices for expediting their promising applications in clinic. In this work, photodynamic-assisted electrochemiluminescence (PDECL) device was constructed for precision diagnosis of Parkinson, where an advanced emitter was prepared by electrostatically linking 2,6-dimethyl-8-(3-carboxyphenyl)4,4'-difluoroboradiazene (BET) with 1-butyl-3-methylimidazole tetrafluoroborate ([BMIm][BF4]). Specifically, protoporphyrin IX (PPIX) can trigger the photodynamic reaction under light irradiation with a wavelength of 450 nm to generate lots of singlet oxygen (1O2), showing a 2.43-fold magnification in the ECL responses. Then, the aptamer (Apt) was assembled on the functional BET-[BMIm] for constructing a "signal off" ECL biosensor. Later on, the PPIX was embedded into the G-quadruplex (G4) of the Apt to magnify the ECL signals for bioanalysis of α-synuclein (α-syn) under light excitation. In the optimized surroundings, the resulting PDECL sensor has a broad linear range of 100.0 aM ∼ 10.0 fM and a low limit of detection (LOD) of 63 aM, coupled by differentiating Parkinson patients from normal individuals according to the receiver operating characteristic (ROC) curve analysis of actual blood samples. Such research holds great promise for synthesis of other advanced luminophores, combined with achieving an early clinical diagnosis.


Assuntos
Compostos de Boro , Técnicas Eletroquímicas , Medições Luminescentes , Doença de Parkinson , Humanos , Doença de Parkinson/diagnóstico , Doença de Parkinson/sangue , Compostos de Boro/química , Técnicas Biossensoriais/métodos , alfa-Sinucleína/análise , alfa-Sinucleína/sangue , Protoporfirinas/química , Aptâmeros de Nucleotídeos/química , Limite de Detecção
18.
Biosens Bioelectron ; 257: 116323, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38669842

RESUMO

Metal nanoclusters (MNCs) have outstanding fluorescence property and biocompatibility, which show widespread applications in biological analysis. Particularly, evaluation of enzyme activity with the fluorescent MNCs has been developed rapidly within the past several years. In this review, we first introduced the fluorescent mechanism of mono- and bi-metallic nanoclusters, respectively, whose interesting luminescence properties are mainly resulted from electron transfer between the lowest unoccupied molecular orbital (LUMO) and highest occupied molecular orbital (HOMO) energy levels. Meanwhile, the charge migration within the structure occurs through ligand-metal charge transfer (LMCT) or ligand-metal-metal charge transfer (LMMCT). On such foundation, diverse enzyme activities were rigorously evaluated, including three transferases and nine hydrolases, in turn harvesting rapid research progresses within past 5 years. Finally, we summarized the design strategies for evaluating enzyme activity with the MNCs, presented the major issues and challenges remained in the relevant research, coupled by showing some improvement measures. This review will attract researchers dedicated to the studies of the MNCs and provide some constructive insights for their further applications in enzyme analysis.


Assuntos
Técnicas Biossensoriais , Ensaios Enzimáticos , Nanopartículas Metálicas , Técnicas Biossensoriais/métodos , Ensaios Enzimáticos/métodos , Nanopartículas Metálicas/química , Humanos , Corantes Fluorescentes/química , Luminescência , Fluorescência
19.
Life (Basel) ; 14(4)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38672781

RESUMO

Extracellular vesicles (EVs) are cell-secreted nanovesicles that play an important role in long-range cell-cell communication. Although EVs pose a promising alternative to cell-based therapy, targeted in vivo delivery still falls short. Many studies have explored the surface modification of EVs to enhance their targeting capabilities. However, to our knowledge, there are no standardized practices to confirm the successful surface modification of EVs or calculate the degree of conjugation on EV surfaces (conjugation efficiency). These pieces of information are essential in the reproducibility of targeted EV therapeutics and the determination of optimized conjugation conditions for EVs to see significant therapeutic effects in vitro and in vivo. This review will discuss the vast array of techniques adopted, technologies developed, and efficiency definitions made by studies that have calculated EV/nanoparticle surface conjugation efficiency and how differences between studies may contribute to differently reported conjugation efficiencies.

20.
BMC Nutr ; 10(1): 59, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641818

RESUMO

To explore the impact of the Mediterranean diet on cardiovascular risk factors, glycemic control and weight loss in patients with type 2 diabetes(T2D) by a meta-analysis of randomized controlled trials (RCTs). We systematically searched PubMed, Cochrance Library, EMBASE and four Chinese databases to identify RCTs that compared the Mediterranean diet with control diets in patients with T2D up to December 2021. The Risk of Bias of the included studies was assessed using the version 2 of the Cochrane risk-of-bias tools for randomized trials (ROB 2). Seven RCTs with 1371 patients met the eligibility criteria and entered into the meta-analysis. Compared to control diets, the beneficial effects of Mediterranean diet were not statistically significant in high-density lipoprotein (MD = 2.33; 95% CI: -0.27 to 4.92), low-density lipoprotein (MD = -2.34; 95% CI -5.67 to 0.99) and total cholesterol (MD = 2.60; 95% CI: -0.95 to 6.15). But Mediterranean diet led to reduce the level of diastolic blood pressure (MD = -1.20; 95% CI: -2.21 to -0.19) and systolic blood pressure (MD = -4.17; 95% CI: -7.12 to -1.22). Meanwhile, Mediterranean diet showed beneficial effects in glycemic control (HbA1[%]: MD = -0.39, 95% CI: -0.58 to -0.20; fasting plasma glucose: MD = -15.12, 95% CI: -24.69 to -5.55) and weight loss (BMI: MD = -0.71, 95% CI: -1.30 to -0.78; WC: MD = -1.69; 95% CI: -3.35 to -0.02) compared to the control diets. The meta-analysis presented evidence supporting the beneficial effects of the Mediterranean diet on blood pressure, glycemic control, and weight loss. However, the impact of the Mediterranean diet on the lipid profile was not found to be significant, warranting further verification. This Meta-analysis was registered on the INPLASY website (Registration number: INPLASY 202160096).

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