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1.
ACS Nano ; 18(33): 22548-22559, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39110641

RESUMO

Mimicking hierarchical assembly in nature to exploit atomically precise artificial systems with complex structures and versatile functions remains a long-standing challenge. Herein, we report two single-crystal supramolecular organic frameworks (MSOF-4 and MSOF-5) based on custom-designed atomically precise gold nanoclusters Au11(4-Mpy)3(PPh3)7, showing distinct and intriguing host-guest adaptation behaviors toward 1-/2-bromopropane (BPR) isomers. MSOF-4 exhibits sev topology and cylindrical channels with 4-mercaptopyridine (4-Mpy) ligands matching well with guest 1-BPR. Due to the confinement effect, solid MSOF-4 undergoes significant structural change upon selective adsorption of 1-BPR vapor over 2-BPR, resulting in strong near-infrared fluorescence. Single-crystal X-ray diffraction reveals that Au11(4-Mpy)3(PPh3)7 in MSOF-4 transforms into Au11Br3(PPh3)7 upon ligand exchange with 1-BPR, resulting in 1-BPR@MSOF-6 single crystals with a rarely reported helical assembly structure. Significantly, the double-helical structure of MSOF-6 facilitates efficient catalysis of the electron transfer (ET) reaction, resulting in a nearly 6 times increase of catalytic rates compared with MSOF-4. In sharp contrast, solid MSOF-5 possesses chb topology and cage-type channels with narrow windows, showing excellent selective physical adsorption toward 1-BPR vapor but a nonfluorescent feature upon guest adsorption. Our results demonstrate a powerful strategy for developing advanced assemblies with high-order complexity and engineering their functions in atomic precision.

2.
Animals (Basel) ; 14(15)2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39123705

RESUMO

Abrupt dietary change can disrupt the intestinal balance in felines. This study aimed to assess the impact of heat-treated Bifidobacterium longum CECT-7384 combined with Fibersol-2 on the intestinal health of adult cats before and after dietary change. We selected 24 British shorthair cats, dividing them into two groups. From day 1 to day 14, the control group received a lower protein (33%) concentration (LPF) diet, while the treated group received the same LPF diet supplemented with 0.16% functional additives, consisting of Bifidobacterium longum CECT-7384 combined with Fibersol-2. Subsequently, from day 15 to day 28, the control group transitioned to a higher protein (40%) concentration (HPF) diet, while the treated group received the same HPF diet supplemented with 0.16% functional additives. Blood and fresh feces were collected on day 0, 14, 17, 21, and 28 of the experiment. The results suggest that the use of heat-treated Bifidobacterium longum CECT-7384 combined with Fibersol-2 may improve gastrointestinal function in cats by reducing serum LPS levels and fecal pH, while increasing fecal sIgA levels. In addition, the functional additive regulates the fecal microbiota and its function, promoting intestinal homeostasis and colonization with beneficial bacteria such as Blautia. Furthermore, on day 28, there was a significant difference in fecal microbiota beta diversity between the two groups. In summary, the addition of heat-treated Bifidobacterium longum CECT-7384 combined with Fibersol-2 contributes to improving the intestinal health of adult cats affected by abrupt dietary change.

3.
ACS Biomater Sci Eng ; 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39163588

RESUMO

The repair and regeneration of maxillofacial bone defects are major clinical challenges. Titanium (Ti)-magnesium (Mg) composites are a new generation of revolutionary internal fixation materials encompassing the mechanical strength and bioactive advantages of Ti and Mg alloys, respectively. This study was aimed to construct a Ti-Mg composite internal plate/screw fixation system to fix and repair bone defects. Further, the effects of different internal fixation systems on bone repair were analyzed through radiological and histological analyses. Notably, Ti6Al4V with rolled Mg foil was used as the experimental group, and a bone defect model of transverse complete amputation of the ulna in rabbits similar to the clinical condition was established. The internal fixation system with the highest osteogenic efficiency was selected based on in vivo results, and the direct and indirect bone repair abilities of the selected materials were evaluated in vitro. Notably, the thin Mg foil-Ti6Al4V internal fixation system exhibited the best fixation effect in the bone defect model and promoted the formation of new bone and early healing of bone defect areas. In vitro, the thin Mg foil-Ti6Al4V composite enhanced the activity of MC3T3-E1 cells; promoted the proliferation, adhesion, extension, and osteogenic differentiation of MC3T3-E1 cells; and regulated new bone formation. Further, it also promoted the polarization of RAW264.7 cells to M2 macrophages, induced the osteogenic immune microenvironment, and indirectly regulated the bone repair process. Therefore, a internal fixation system holds a promising potential for the internal fixation of maxillofacial bone defects. Our findings provide a theoretical and scientific basis for the design and clinical application of Ti-Mg internal fixation systems.

4.
BMC Psychiatry ; 24(1): 575, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39180019

RESUMO

BACKGROUND: Major depressive disorder (MDD) is a highly heterogeneous disease, with differences in clinical manifestations among depression patients based on onset ages and genders. The neural mechanisms underlying these differences remain unclear. In this study, we utilized resting state functional imaging data from a large sample database and adopted the ReHo method to investigate gender differences in local brain function in MDD patients across different onset age groups. METHODS: The study included 364 MDD patients and 695 healthy participants who were part of the REST-meta-MDD project. Regional homogeneity (ReHo) assessed gender disparities in MDD and healthy individuals within groups delineated by gender and onset age (young group: 18-29 years; middle-aged group: 30-45 years). RESULTS: Among the young MDD groups, there were significant gender differences in the right superior frontal gyrus, right inferior frontal gyrus, left superior temporal gyrus, and right superior parietal lobule, with male MDD patients having higher ReHo values compared to females. When compared to healthy males, male MDD patients exhibited elevated ReHo values in the right superior parietal lobule. In the middle-aged groups, a marked ReHo difference was observed in the bilateral cerebellum posterior lobe, with female MDD patients showing higher ReHo values. CONCLUSIONS: The functional mechanisms of MDD differ between genders and show distinct variations across different onset age groups. These findings underscore the importance of developing personalized interventions that address the unique needs of MDD patients, tailored to their gender and age, and necessitate the development of antidepressant medications targeted at each gender-age subgroup.


Assuntos
Transtorno Depressivo Maior , Imageamento por Ressonância Magnética , Humanos , Transtorno Depressivo Maior/fisiopatologia , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Adolescente , Fatores Sexuais , Idade de Início , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem , Fatores Etários , Caracteres Sexuais
6.
Angew Chem Int Ed Engl ; : e202411871, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39054405

RESUMO

Advancing catalyst design is pivotal for the enhancement of photocatalytic processes in renewable energy conversion. The incorporation of structural chirality into conventional inorganic solar hydrogen nanocatalysts promises a significant transformation in catalysis, a feature absent in this field. Here we unveil the unexplored potential of geometric chirality by creating a chiral composite that integrates geometric chiral Au nanoparticles (NPs) with two-dimensional C3N4 nanosheets, significantly boosting photocatalytic H2 evolution beyond the achiral counterparts. The superior performance is driven by the geometric chirality of Au NPs, which facilitates efficient charge carrier separation through the favorable C3N4-chiral Au NP interface and chiral induced spin polarization, and exploits high-activity facets within the concave surfaces of chiral Au NPs. The resulting synergistic effect leads to a remarkable increase in photocatalytic H2 evolution, with an apparent quantum yield of 44.64% at 400 nm. Furthermore, we explore the selective polarized photo-induced carrier separation behavior, revealing a distinct chiral-dependent photocatalytic HER performance. Our work advances the design and utilization of chiral inorganic nanostructures for superior performance in energy conversion processes.

7.
Am J Transl Res ; 16(5): 2011-2023, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38883387

RESUMO

OBJECTIVES: The increasing issue of bacterial resistance, coupled with inadequate progress in developing new antibiotics, necessitates exploring alternative treatments. Antibacterial biomaterials, such as silver and copper, possess advantageous properties such as heat resistance, durability, continuity, and safety. Particularly, they can effectively eliminate pathogenic bacteria while preserving cellular integrity, emphasizing the necessity of identifying optimal metal ion concentrations for practical application. Caenorhabditis elegans (C. elegans) can serve as a noteworthy model in this context. This study employed a C. elegans infection model to assess the efficacy of antibacterial metal ions. METHODS: Hematoxylin-eosin (HE) staining and inductively coupled plasma mass spectrometry (ICP-MS) assay were utilized to determine the toxic levels of metal ions in mice. Additionally, RNA sequencing (RNA-seq) and assessment of reactive oxygen species (ROS) production in the C. elegans model were conducted to elucidate the mechanisms underlying metal ion toxicity. RESULTS: Silver ion concentrations ranging from 10-6 to 10-7 M and copper ion concentrations ranging from 10-4 to 10-5 M exhibited antimicrobial properties without eliciting cytotoxic effects. Analysis of the transcriptome data derived from mRNA isolated from C. elegans indicated that CRKP infection activated the FoxO signaling pathway, potentially leading to ROS accumulation and C. elegans demise. CONCLUSIONS: In conclusion, C. elegans serves as a comprehensive infection model for assessing antibacterial metal ions.

8.
Bioact Mater ; 40: 34-46, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38910967

RESUMO

For gastrointestinal anastomosis, metallic biodegradable staples have a broad application potential. However, both magnesium and zinc alloys have relatively low strength to withstand the repeated peristalsis of the gastrointestinal tract. In this study, we developed a novel kind of biodegradable high-nitrogen iron (HN-Fe) alloy wires (0.23 mm), which were fabricated into the staples. The tensile results showed that the ultimate tensile strength and elongation of HN-Fe wires were 1023.2 MPa and 51.0 %, respectively, which was much higher than those of other biodegradable wires. The degradation rate in vitro of HN-Fe wires was slightly higher than that of pure Fe wires. After 28 days of immersion, the tensile strength of HN-Fe wires remained not less than 240 MPa, meeting the clinical requirements. Furthermore, sixteen rabbits were enrolled to conduct a comparison experiment using HN-Fe and clinical Ti staples for gastroanastomosis. After 6 months of implantation, a homogeneous degradation product layer on HN-Fe staples was observed and no fracture occurred. The degradation rate of HN-Fe staples in vivo was significantly higher than that in vitro, and they were expected to be completely degraded in 2 years. Meanwhile, both benign cutting and closure performance of HN-Fe staples ensured that all the animals did not experience hemorrhage and anastomotic fistula during the observation. The anastomosis site healed without histopathological change, inflammatory reaction and abnormal blood routine and biochemistry, demonstrating good biocompatibility of HN-Fe staples. Thereby, the favorable performance makes the HN-Fe staples developed in this work a promising candidate for gastrointestinal anastomosis.

9.
J Integr Neurosci ; 23(3): 48, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38538212

RESUMO

In the context of perceiving individuals within and outside of social groups, there are distinct cognitive processes and mechanisms in the brain. Extensive research in recent years has delved into the neural mechanisms that underlie differences in how we perceive individuals from different social groups. To gain a deeper understanding of these neural mechanisms, we present a comprehensive review from the perspectives of facial recognition and memory, intergroup identification, empathy, and pro-social behavior. Specifically, we focus on studies that utilize functional magnetic resonance imaging (fMRI) and event-related potential (ERP) techniques to explore the relationship between brain regions and behavior. Findings from fMRI studies reveal that the brain regions associated with intergroup differentiation in perception and behavior do not operate independently but instead exhibit dynamic interactions. Similarly, ERP studies indicate that the amplitude of neural responses shows various combinations in relation to perception and behavior.


Assuntos
Empatia , Reconhecimento Facial , Humanos , Imageamento por Ressonância Magnética , Encéfalo/fisiologia , Potenciais Evocados/fisiologia , Mapeamento Encefálico , Comportamento Social
11.
Heliyon ; 10(2): e24324, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38298698

RESUMO

Human activities along southwest border of China exert significant influences on sustainable development of regional economy, politics, and environment among countries Vietnam, Laos, and Myanmar. However, related empirical studies remain very limited due to the low availability and comparability of small-scale statistic data in that region. Fortunately, Nighttime light (NTL) images provide uniform, consistent and valuable data sources. Using NTL data from 1992 to 2013, this article seeks to contribute the literature by investigating the trend of relative intensity of human activities between China and her southwest neighborhoods. We find that the human activities intensity of Chinese borderland maintained advantage over her neighborhoods, and the trend of this advantage is nonlinear. Regional development policy launched by Chinese government is considered to be a possible explanation.

12.
Bioact Mater ; 35: 306-329, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38362138

RESUMO

Objectives: To examine the 16-year developmental history, research hotspots, and emerging trends of zinc-based biodegradable metallic materials from the perspective of structural and temporal dynamics. Methods: The literature on zinc-based biodegradable metallic materials in WoSCC was searched. Historical characteristics, the evolution of active topics and development trends in the field of zinc-based biodegradable metallic materials were analyzed using the bibliometric tools CiteSpace and HistCite. Results: Over the past 16 years, the field of zinc-based biodegradable metal materials has remained in a hotspot stage, with extensive scientific collaboration. In addition, there are 45 subject categories and 51 keywords in different research periods, and 80 papers experience citation bursts. Keyword clustering anchored 3 emerging research subfields, namely, #1 plastic deformation #4 additive manufacturing #5 surface modification. The keyword alluvial map shows that the longest-lasting research concepts in the field are mechanical property, microstructure, corrosion behavior, etc., and emerging keywords are additive manufacturing, surface modification, dynamic recrystallization, etc. The most recent research on reference clustering has six subfields. Namely, #0 microstructure, #2 sem, #3 additive manufacturing, #4 laser powder bed fusion, #5 implant, and #7 Zn-1Mg. Conclusion: The results of the bibliometric study provide the current status and trends of research on zinc-based biodegradable metallic materials, which can help researchers identify hot spots and explore new research directions in the field.

13.
Medicine (Baltimore) ; 103(4): e36143, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38277564

RESUMO

For exploring the positive relief effect and application value of cluster nursing strategies on stroke patients with dysphagia in rehabilitation medicine. A retrospective analysis was conducted on 70 patients with stroke dysphagia admitted to the Rehabilitation Medicine Department of our hospital from June 2021 to November 2022; by comparison, patients were separated into intervention group (IG) and control group (CG) according to different degrees of swallowing difficulty, and nutritional nursing interventions were conducted on the selected research subjects. It was given routine care in the CG and a cluster nursing strategy in the IG, with a total intervention time of 5 months. Before intervention, general information of all patients was compared. Before and after intervention, the incidence of aspiration, nutritional biochemical indicators (hemoglobin, total serum protein, albumin, prealbumin, total cholesterol), grip strength, Swallowing Quality of Life score, etc were collected from the 2 groups of patients. Finally, the specific benefits were analyzed through statistical results to evaluate the intervention effect. After intervention, the explicit aspiration rate of the participants in this experiment significantly decreased, and the difference among the participants in this experiment was statistically significant (P < .05); the implicit aspiration rate was not statistically significant (P > .05). In the comparison of nursing expenses, the CG spent 5403.57 ± 815.51 yuan, while the IG spent 5237.10 ± 758.35 yuan. There was a statistically marked disparity among the participants in this experiment (t = 52.41, P < .001). In the comparison of hospitalization expenses, the cost of the CG was 9236.05 ± 3236.08 yuan; The cost of the IG was 9538.59 ± 4985.21 yuan, and there was a marked disparity among the participants in this experiment (P < .001). The significant statistical significance exists (P < .05) in the 5 indicators of hemoglobin, total protein, prealbumin, albumin, and total cholesterol, quality of life scores, and patient physical efficacy in both groups. The intervention study of cluster nursing strategy for stroke patients with dysphagia in rehabilitation medicine can effectively reduce the incidence of overt aspiration and ultimately improve their quality of life. It has high clinical application value.


Assuntos
Transtornos de Deglutição , Acidente Vascular Cerebral , Humanos , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/reabilitação , Pré-Albumina , Qualidade de Vida , Estudos Retrospectivos , Acidente Vascular Cerebral/complicações , Hemoglobinas , Colesterol
14.
ACS Appl Mater Interfaces ; 16(2): 2027-2040, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38183285

RESUMO

Hydrogel materials have proven valuable in wound healing, but improving the safety of these hydrogels is still challenging. Therefore, designing multifunctional natural polymeric-based hydrogels with excellent mechanical properties to replace toxic or potentially risky, refractory chemical polymer-based hydrogels such as polyacrylamide and polyethylene glycol is of particular significance. Here, a green starch-based hydrogel (Starch@Ca/CGC hydrogel) with injectability, self-healing, and instant adhesion was constructed by coordination interaction, electrostatic interaction, and intramolecular and intermolecular hydrogen bonds. Therein, natural bioactive small molecules gallic acid (GA) and carvacrol (CA) were coordinated with metal ions by the ultrasonic-triggered self-assembly and ionic cross-linking codriven strategy to prepare Cu-gallic acid-carvacrol nanospheres (CGC NPs), which conferred the hydrogel with near-infrared light (NIR)-controlled CA release and photothermal synergistic sterilization properties, as well as antioxidant and anti-infection capabilities. More importantly, the multifunctional hydrogel platforms could completely cover an irregular wound shape to prevent secondary injury and significantly accelerate wound healing under NIR with more skin appendages like hair follicles and blood vessels appearing. Therefore, it is expected that this starch-based hydrogel could serve as a competitive multifunctional dressing in the biomedical field, including bacteria-derived wound infection and other tissue repair.


Assuntos
Antibacterianos , Cimenos , Cicatrização , Humanos , Aderências Teciduais , Antibacterianos/farmacologia , Ácido Gálico , Hidrogéis/farmacologia
15.
Nucleic Acids Res ; 52(D1): D1097-D1109, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37831118

RESUMO

Antibody-drug conjugates (ADCs) are a class of innovative biopharmaceutical drugs, which, via their antibody (mAb) component, deliver and release their potent warhead (a.k.a. payload) at the disease site, thereby simultaneously improving the efficacy of delivered therapy and reducing its off-target toxicity. To design ADCs of promising efficacy, it is crucial to have the critical data of pharma-information and biological activities for each ADC. However, no such database has been constructed yet. In this study, a database named ADCdb focusing on providing ADC information (especially its pharma-information and biological activities) from multiple perspectives was thus developed. Particularly, a total of 6572 ADCs (359 approved by FDA or in clinical trial pipeline, 501 in preclinical test, 819 with in-vivo testing data, 1868 with cell line/target testing data, 3025 without in-vivo/cell line/target testing data) together with their explicit pharma-information was collected and provided. Moreover, a total of 9171 literature-reported activities were discovered, which were identified from diverse clinical trial pipelines, model organisms, patient/cell-derived xenograft models, etc. Due to the significance of ADCs and their relevant data, this new database was expected to attract broad interests from diverse research fields of current biopharmaceutical drug discovery. The ADCdb is now publicly accessible at: https://idrblab.org/adcdb/.


Assuntos
Bases de Dados de Produtos Farmacêuticos , Descoberta de Drogas , Imunoconjugados , Animais , Humanos , Anticorpos/uso terapêutico , Antineoplásicos/uso terapêutico , Produtos Biológicos , Linhagem Celular Tumoral , Modelos Animais de Doenças , Imunoconjugados/farmacologia , Imunoconjugados/uso terapêutico
16.
Small ; 20(13): e2308164, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37948426

RESUMO

Rechargeable aqueous zinc-ion batteries are practically plagued by the short lifespan and low Coulombic efficiency (CE) of Zn anodes resulting from random dendrite deposition and parasitic reactions. Herein, the host-guest chemistry of cucurbituril additive with Zn2+ to achieve longstanding Zn anodes is manipulated. The macrocyclic molecule of cucurbit[5]uril (CB[5]) is delicately designed to reconstruct both the CB[5]-adsorbed electric-double layer (EDL) structure at the Zn interface and the hydrated sheath of Zn2+ ions. Especially benefiting from the desirable carbonyl rims and suitable hydrophobic cavities, the CB[5] has a strong host-guest interaction with Zn2+ ions, which exclusively permits rapid Zn2+ flux across the EDL interface but retards the H2O radicals and SO4 2-. Accordingly, such a unique particle redistributor warrants long-lasting dendrite-free deposition by homogenizing Zn nucleation/growth and significantly improved CE by inhibiting side reactions. The Zn anode can deliver superior reversibility in CB[5]-containing electrolyte with a ninefold increase of cycle lifetime and an elevated CE of 99.7% under harsh test conditions (10 mA cm-2/10 mA h cm-2). The work opens a new avenue from the perspective of host-guest chemistry to propel the development of rechargeable Zn metal batteries and beyond.

17.
Adv Mater ; 36(3): e2309033, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37944554

RESUMO

Chirality introduces a new dimension of functionality to materials, unlocking new possibilities across various fields. When integrated with plasmonic hybrid nanostructures, this attribute synergizes with plasmonic and other functionalities, resulting in unprecedented chiroptical materials that push the boundaries of the system's capabilities. Recent advancements have illuminated the remarkable chiral light-matter interactions within chiral plasmonic hybrid nanomaterials, allowing for the harnessing of their tunable optical activity and hybrid components. These advancements have led to applications in areas such as chiral sensing, catalysis, and spin optics. Despite these promising developments, there remains a need for a comprehensive synthesis of the current state-of-the-art knowledge, as well as a thorough understanding of the construction techniques and practical applications in this field. This review begins with an exploration of the origins of plasmonic chirality and an overview of the latest advancements in the synthesis of chiral plasmonic hybrid nanostructures. Furthermore, representative emerging categories of hybrid nanomaterials are classified and summarized, elucidating their versatile applications. Finally, the review engages with the fundamental challenges associated with chiral plasmonic hybrid nanostructures and offer insights into the future prospects of this advanced field.

18.
Chemosphere ; 349: 140929, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38092169

RESUMO

Fungi outbreaks in water will include a series of processes, including spore aggregation, germination, biofilm, and finally present in a mixed state in the aquatic environment. More attention is paid to the control of dispersed fungal spores, however, there was little knowledge of the control of germinated spores. This study investigated the inactivation kinetics and mechanism of ultraviolet (UV) treatment for fungal spores with different germination percentages compared with dormant spores. The results indicated that the inactivation rate constants (k) of spores with 5%-45% germination were 0.0278-0.0299 cm2/mJ for Aspergillus niger and 0.0588-0.0647 cm2/mJ for Penicillium polonicum, which were lower than those of dormant spores. It suggested that germinated spores were more tolerant to UV irradiation than dormant spores, and it may be due to the defensive barrier (upregulated pigments) and some reductive substance (upregulated enoyl reductase) by absorbing UV or reacting with reactive oxygen species according to transcriptome analysis. Compared to dormant spores, the k-UV of germinated spores decreased by 18.17%-26.56% for Aspergillus niger, which was less than k-chlorine (62.33%-69.74%). A slighter decrease in k-UV showed UV irradiation can efficiently control fungi contamination, especially when dormant spores and germinated spores coexisted in actual water systems. This study indicates that more attention should be paid to germinated spores.


Assuntos
Cloro , Raios Ultravioleta , Cloro/farmacologia , Esporos Fúngicos , Água , Aspergillus niger , Esporos Bacterianos
19.
J Am Chem Soc ; 146(4): 2798-2804, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38145451

RESUMO

The combination of the chiral concept and inorganic nanostructures holds great potential for significantly impacting catalytic processes and products. However, the synthesis of inorganic nanomaterials with engineered chiroptical activity and identical structure and size presents a substantial challenge, impeding exploration of the relationship between chirality (optical activity) and catalytic efficiency. Here, we present a facile wet-chemical synthesis for achieving intrinsic and tunable chiroptical activity within colloidal copper oxide nanostructures. These nanostructures exhibit strong spin-polarization selectivity compared with their achiral counterparts. More importantly, the ability to engineer chiroptical activity within the same type of chiral nanostructures allows for the manipulation of spin-dependent catalysis, facilitating a study of the connection between the chiroptical magnitude (asymmetric factor) and catalytic performance in inorganic nanostructures. Specifically, using these materials as model catalysts in a proof-of-concept catalytic reaction, we reveal a linear correlation between the asymmetric factor of chiral nanomaterials and the efficiency of the catalytic reaction. This work paves the way for the development of chiral inorganic nanosystems and their application in catalysis through chiroptical engineering.

20.
Infect Drug Resist ; 16: 7671-7681, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38144224

RESUMO

Purpose: This study aimed to investigate the molecular characteristics, antimicrobial resistance, and biofilm-forming ability of Staphylococcus aureus isolates from invasive infections. Methods: A total of 92 non-repetitive S. aureus isolates from invasive infections were analyzed by Multi-locus Sequence Typing (MLST), spa typing, and chromosomal cassette mec (SCCmec) typing. Antibiotic susceptibility testing was performed using the disk diffusion and agar dilution methods. Biofilm-forming ability was assessed using crystal violet assay. The presence and expression of biofilm-associated genes were examined using PCR and RT-qPCR. Results: Among the 55 Methicillin-resistant S. aureus (MRSA) and 41 Methicillin-sensitive S. aureus (MSSA) isolates, ST59 (43.6%) predominated in MRSA, while ST7 (39.0%) was most common in MSSA. As expected, MRSA exhibited higher antibiotic resistance rates compared to MSSA isolates. Biofilm formation assays revealed that the majority of isolates (88.5%) produced biofilms, with 26.0% classified as strong producers (OD570 ≥ 1.0) and 62.5% as weak producers (0.2 ≤ OD570<1.0). MSSA exhibited a higher biofilm-forming ability than MRSA (P < 0.01), with variations across clones. Notably, ST7 isolates displayed greater biofilm-forming ability than other sequence types (ST59, ST5, and ST239). RT-qPCR results revealed that ST7 isolates exhibited higher expression levels of icaA compared to other sequence types. Conclusion: This study revealed significant molecular heterogeneity among invasive S. aureus isolates, with ST59 and ST7 as dominant clones. The strong biofilm-forming capacity of ST7 merits concern given its rising prevalence regionally. Continuous surveillance of emerging successful lineages is critical to help guide infection control strategies against invasive S. aureus infections.

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