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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 308: 123754, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38091646

RESUMO

The unreasonable spraying and random migration of acetamiprid may cause pollution of crops, soil and water resources in the environment, resulting in threatening ecosystem and human health. However, the monitoring of acetamiprid using mass spectrum in the environment encounters challenges due to high-cost instruments and complex processing time. Herein, we fabricated a rapid and reliable SERS method based on Ag@ZIF-8@Au platforms for tracing acetamiprid residues in the environment. In this method, a MOF material named ZIF-8 is coated with silver nanoparticles and distributed internally between AgNPs and AuNPs to enhance Raman signal, which can enrich pesticide molecules into the hotspots area provided by noble material and helps avoid the oxidation of silver nanoparticles. High sensitivity (LOD of 9.027 × 10-10 M for acetamiprid, and SERS enhancement factor of 4.3 × 107), excellent reproducibility (6.496% or 7.198% RSD for 30 random points) and superior stability (3.127% RSD for 6 weeks) were achieved using the proposed method. Acetamiprid with concentrations from 10-4 to 10-9 M were successfully detected by SERS method. Furthermore, the linear detection models of acetamiprid in different environment matrices (lake water, tea leaves, tea garden soil, oranges and oranges orchard soil) were established and all the correlation coefficient (R2) were higher than or equal to 95%, indicating the excellent adaptability of Ag@ZIF-8@Au platform in environment. The randomly spiked concentrations of acetamiprid were also tested with good recovery values and low relative error values, further confirming the reliability of the detection method.


Assuntos
Ouro , Nanopartículas Metálicas , Neonicotinoides , Humanos , Ouro/química , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes , Prata/química , Ecossistema , Chá , Solo , Análise Espectral Raman/métodos
2.
J Cancer Res Ther ; 19(6): 1495-1500, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38156914

RESUMO

In December 2022, the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) became dominant in China due to its high infectivity and lower mortality rate. The risk of critical illness and mortality among patients with hematologic malignancies who contracted SARS-CoV-2 was particularly high. The aim of this study was to draft a consensus to facilitate effective treatments for these patients based on the type and severity of the disease. Following the outbreak of the novel coronavirus in China, a steering committee consisting of experienced hematologists was formed by the Specialized Committee of Oncology and Microecology of the Chinese Anti-Cancer Association. The expert group drafted a consensus on the management and intervention measures for different types of hematologic malignancies based on the clinical characteristics of the Omicron variant of the SARS-CoV-2 infection, along with relevant guidelines and literature. The expert group drafted independent recommendations on several important aspects based on the epidemiology of the Omicron variant in China and the unique vulnerability of patients with hematologic malignancies. These included prophylactic vaccinations for those with hematologic malignancies, the use of plasma from blood donors who recovered from the novel coronavirus infection, the establishment of negative pressure wards, the use of steady-state mobilization of peripheral blood hematopoietic stem cells, the provision of psychological support for patients and medical staff, and a focus on maintaining a healthy intestinal microecology.


Assuntos
COVID-19 , Neoplasias Hematológicas , Humanos , SARS-CoV-2 , Consenso , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/terapia , China/epidemiologia
3.
Sci Rep ; 13(1): 22661, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38114593

RESUMO

Colorectal cancer is one of the most common malignancies worldwide. Although initially effective, patients who receive chemotherapy ultimately experience various complications and develop chemo-resistance, leading to cancer recurrence. Therefore, we aimed to find a drug with good efficacy and low toxicity that could enhance the treatment with 5-Fluorouracil (a commonly used clinical drug) and reduce its dosing. Corilagin, an anti-tumor natural product, has received widespread attention. Glucose regulated protein 78 (GRP78) is overexpressed in colorectal cancer cells and plays a key role in the proliferation, migration and drug resistance of cancer cells. Importantly, GRP78 can affect the apoptosis induced by 5-fluorouracil in CRC cells. In the present study, we determined the synergistic anti-tumor activity of the combination treatment by cell proliferation assay, apoptosis assay, fluorescent staining, cell cycle analysis, WB and PCR assays. This synergistic effect was associated with S-phase blockade, intracellular reactive oxygen species production and downregulation of GRP78. Taken together, our results indicate that Corilagin acts as a potentiator of 5-fluorouracil and may have therapeutic potential for patients with CRC.


Assuntos
Neoplasias Colorretais , Chaperona BiP do Retículo Endoplasmático , Humanos , Proliferação de Células , Recidiva Local de Neoplasia/tratamento farmacológico , Fluoruracila/uso terapêutico , Neoplasias Colorretais/patologia , Apoptose , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos
4.
Diagnostics (Basel) ; 13(21)2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37958220

RESUMO

Liver diseases have long been a prevalent cause of morbidity and mortality, and their development and progression involve multiple vital organs throughout the body. Recent studies on the oral-gut-liver axis have revealed that the oral microbiota is associated with the pathophysiology of chronic liver diseases. Since interventions aimed at regulating oral biological disorders may delay the progress of liver disease, it is crucial to better comprehend this process. Oral bacteria with potential pathogenicity have been extensively studied and are closely related to several types of chronic liver diseases. Therefore, this review will systemically describe the emerging role of oral pathogenic bacteria in common liver diseases, including alcoholic liver disease (ALD), non-alcoholic steatohepatitis (NASH), non-alcoholic fatty liver disease (NAFLD), cirrhosis, autoimmune liver diseases (AILD), and liver cancer, and bring in new perspectives for future research.

5.
Curr HIV Res ; 21(5): 301-313, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37936463

RESUMO

BACKGROUND: Acquired immune deficiency syndrome (AIDS) is a serious worldwide public health problem and has become the focus of prevention and control in China, while the student population is the key population for AIDS prevention. OBJECTIVE: The purpose of this study was to investigate the effects of cognitive behavioral therapy (CBT) on college students' AIDS-related cognitions, attitudes, and behaviors, and to find programmatic strategies for AIDS prevention in terms of changing college students' cognitions and behaviors. METHODS: In a cluster randomized controlled trial, 233 undergraduate students were assigned to the CBT group (CBT-based intervention, n=92), the TAU group (treatment as usual, n=72), and the CON group (no intervention, n=59). AIDS-related knowledge, attitudes, and behaviors of participants were assessed at pre-intervention, post-intervention, and follow-up. RESULTS: After one month of the study, AIDS-related knowledge, attitudes, and behaviors improved in both the TAU and CBT groups, while there were no significant changes in the CON group. The intervention effect was more significant and sustainable in the CBT group compared to the TAU group. CONCLUSIONS: The application of CBT in AIDS prevention among college students is feasible, acceptable, and effective. CBT can increase the level of knowledge about AIDS, improve AIDS-related attitudes, and increase willingness to use condoms. CBT is expected to replace traditional health education as an innovative tool for AIDS prevention because of its long-lasting and efficacious nature.


Assuntos
Síndrome da Imunodeficiência Adquirida , Terapia Cognitivo-Comportamental , Infecções por HIV , Humanos , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Infecções por HIV/prevenção & controle , Educação em Saúde , Estudantes/psicologia
6.
Microorganisms ; 10(11)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36363799

RESUMO

Microorganisms have long been known to play key roles in the initiation and development of tumors. The oral microbiota and tumorigenesis have been linked in epidemiological research relating to molecular pathology. Notably, some bacteria can impact distal tumors by their gastrointestinal or blood-borne transmission under pathological circumstances. Certain bacteria drive tumorigenesis and progression through direct or indirect immune system actions. This review systemically discusses the recent advances in the field of oral microecology and tumor, including the oncogenic role of oral microbial abnormalities and various potential carcinogenesis mechanisms (excessive inflammatory response, host immunosuppression, anti-apoptotic activity, and carcinogen secretion) to introduce future directions for effective tumor prevention.

7.
Infect Drug Resist ; 15: 5137-5148, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36082242

RESUMO

Background: blaNDM-1-producing Acinetobacter baumannii (BP-AB) remains a critical problem in nosocomial infections, because of its resistance mediated by the biofilm formation and virulence factors. No studies have confirmed myrtenol's efficacy in inhibiting the biofilm formation and virulence associated with biofilm of BP-AB. Methods: The tested concentrations of myrtenol were wild type (A), 50 µg/mL (B), 100 µg/mL (C), 200 µg/mL (D), 250 µg/mL (E), and 300 µg/mL (F). Results: The BP-AB biofilm inhibition was significantly higher in the D, E, and F groups than in the A, B, and C groups. Myrtenol significantly reduced the air-liquid interface ring formation in glass tubes. It also effectively inhibited the attachment of BP-AB strains on polystyrene surfaces as shown by crystal violet staining. Microscopy showed a significant reduction in biofilm formation with dispersed BP-AB strains. The confocal laser scanning microscopy analysis showed a significant reduction in the biofilm's biomass, covered surface area, and thickness. The scanning electron microscopy analysis revealed significantly fewer BP-AB aggregates on the coverslip surface. In the CompStat analysis, the biofilm's biomass, maximum thickness, and surface-to-volume ratio were significantly reduced. The qPCR analysis revealed a significant down-regulation of bfmR, bap, csuA/B, and ompA expression, which positively correlated with the biofilm's biomass, maximum thickness, and surface-to-volume ratio in BP-AB strains. Myrtenol significantly improved the susceptibility of BP-AB to the antibiotics amikacin, piperacillin/tazobactam, cefoperazone/sulbactam, and ceftazidime. Conclusion: Myrtenol attenuates the BP-AB biofilm formation and virulence by suppressing the expression of bfmR, bap, csuA/B, and ompA.

8.
J Cancer Res Ther ; 18(7): 1835-1844, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36647940

RESUMO

The human gut microbiota represents a complex ecosystem that is composed of bacteria, fungi, viruses, and archaea. It affects many physiological functions including metabolism, inflammation, and the immune response. The gut microbiota also plays a role in preventing infection. Chemotherapy disrupts an organism's microbiome, increasing the risk of microbial invasive infection; therefore, restoring the gut microbiota composition is one potential strategy to reduce this risk. The gut microbiome can develop colonization resistance, in which pathogenic bacteria and other competing microorganisms are destroyed through attacks on bacterial cell walls by bacteriocins, antimicrobial peptides, and other proteins produced by symbiotic bacteria. There is also a direct way. For example, Escherichia coli colonized in the human body competes with pathogenic Escherichia coli 0157 for proline, which shows that symbiotic bacteria compete with pathogens for resources and niches, thus improving the host's ability to resist pathogenic bacteria. Increased attention has been given to the impact of microecological changes in the digestive tract on tumor treatment. After 2019, the global pandemic of novel coronavirus disease 2019 (COVID-19), the development of novel tumor-targeting drugs, immune checkpoint inhibitors, and the increased prevalence of antimicrobial resistance have posed serious challenges and threats to public health. Currently, it is becoming increasingly important to manage the adverse effects and complications after chemotherapy. Gastrointestinal reactions are a common clinical presentation in patients with solid and hematologic tumors after chemotherapy, which increases the treatment risks of patients and affects treatment efficacy and prognosis. Gastrointestinal symptoms after chemotherapy range from nausea, vomiting, and anorexia to severe oral and intestinal mucositis, abdominal pain, diarrhea, and constipation, which are often closely associated with the dose and toxicity of chemotherapeutic drugs. It is particularly important to profile the gastrointestinal microecological flora and monitor the impact of antibiotics in older patients, low immune function, neutropenia, and bone marrow suppression, especially in complex clinical situations involving special pathogenic microbial infections (such as clostridioides difficile, multidrug-resistant Escherichia coli, carbapenem-resistant bacteria, and norovirus).


Assuntos
COVID-19 , Microbiota , Neoplasias , Idoso , Humanos , Bactérias , Consenso , Escherichia coli , Trato Gastrointestinal , Neoplasias/tratamento farmacológico , China
9.
Langmuir ; 37(23): 7246-7253, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34081481

RESUMO

Self-assembling colloidal particles into clathrate hydrates requires the particles to have tetrahedral bonds in the eclipsed conformation. It has been suggested that colloidal particles with eclipsed triangular-shaped patches can form clusters in the eclipsed conformation that leads to colloidal clathrate hydrates. However, in experiments, patches have been limited to circular shapes due to surface energy minimization. Here, we extend the particle synthesis strategy and show that colloidal particles with triangular patches can be readily fabricated by controlling the viscosity of the liquid oil droplets during a colloidal fusion process. The position, orientation, curvature, shape, and size of the patches are all exclusively determined by the intrinsic symmetry of the colloidal clusters, resulting in dipatch particles with eclipsed patches and tetrahedral patchy particles with patch vertices pointing toward each other. Patch curvature can be controlled by tuning the viscosity of the oil droplets and using different surfactants. Using strain-promoted azide-alkyne cycloaddition, single-stranded DNA can be selectively functionalized on the patches. However, after annealing these particles, dipatch particles form chains because the patches are too small to form clathrate hydrates. Under certain conditions, tetrahedral triangular patchy particles should prefer the eclipsed conformation, as it maximizes DNA hybridization. However, we observe random aggregates, which result from having triangular patches that are too big. We estimate that tetrahedral patchy particles that can crystallize need to be less than 1 µm in diameter.


Assuntos
Azidas , Coloides , Alcinos , Reação de Cicloadição
10.
Chem Soc Rev ; 50(10): 5898-5951, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34027954

RESUMO

Over the last three decades, photonic crystals (PhCs) have attracted intense interests thanks to their broad potential applications in optics and photonics. Generally, these structures can be fabricated via either "top-down" lithographic or "bottom-up" self-assembly approaches. The self-assembly approaches have attracted particular attention due to their low cost, simple fabrication processes, relative convenience of scaling up, and the ease of creating complex structures with nanometer precision. The self-assembled colloidal crystals (CCs), which are good candidates for PhCs, have offered unprecedented opportunities for photonics, optics, optoelectronics, sensing, energy harvesting, environmental remediation, pigments, and many other applications. The creation of high-quality CCs and their mass fabrication over large areas are the critical limiting factors for real-world applications. This paper reviews the state-of-the-art techniques in the self-assembly of colloidal particles for the fabrication of large-area high-quality CCs and CCs with unique symmetries. The first part of this review summarizes the types of defects commonly encountered in the fabrication process and their effects on the optical properties of the resultant CCs. Next, the mechanisms of the formation of cracks/defects are discussed, and a range of versatile fabrication methods to create large-area crack/defect-free two-dimensional and three-dimensional CCs are described. Meanwhile, we also shed light on both the advantages and limitations of these advanced approaches developed to fabricate high-quality CCs. The self-assembly routes and achievements in the fabrication of CCs with the ability to open a complete photonic bandgap, such as cubic diamond and pyrochlore structure CCs, are discussed as well. Then emerging applications of large-area high-quality CCs and unique photonic structures enabled by the advanced self-assembly methods are illustrated. At the end of this review, we outlook the future approaches in the fabrication of perfect CCs and highlight their novel real-world applications.

11.
Angew Chem Int Ed Engl ; 60(11): 5744-5748, 2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33285024

RESUMO

This contribution describes the synthesis of colloidal di-patch particles functionalized with DNA on the patches and their assembly into colloidal superstructures via cooperative depletion and DNA-mediated interactions. The assembly into flower-like Kagome, brick-wall like monolayer, orthogonal packed single or double layers, wrinkled monolayer, and colloidal honeycomb superstructures can be controlled by tuning the particles' patch sizes and assembly conditions. Based on these experimental results, we generate an empirical phase diagram. The principles revealed by the phase diagram provide guidance in the design of two-dimensional (2D) materials with desired superstructures. Our strategy might be translatable to the assembly of three-dimensional (3D) colloidal structures.

12.
Nature ; 585(7826): 524-529, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32968261

RESUMO

Self-assembling colloidal particles in the cubic diamond crystal structure could potentially be used to make materials with a photonic bandgap1-3. Such materials are beneficial because they suppress spontaneous emission of light1 and are valued for their applications as optical waveguides, filters and laser resonators4, for improving light-harvesting technologies5-7 and for other applications4,8. Cubic diamond is preferred for these applications over more easily self-assembled structures, such as face-centred-cubic structures9,10, because diamond has a much wider bandgap and is less sensitive to imperfections11,12. In addition, the bandgap in diamond crystals appears at a refractive index contrast of about 2, which means that a photonic bandgap could be achieved using known materials at optical frequencies; this does not seem to be possible for face-centred-cubic crystals3,13. However, self-assembly of colloidal diamond is challenging. Because particles in a diamond lattice are tetrahedrally coordinated, one approach has been to self-assemble spherical particles with tetrahedral sticky patches14-16. But this approach lacks a mechanism to ensure that the patchy spheres select the staggered orientation of tetrahedral bonds on nearest-neighbour particles, which is required for cubic diamond15,17. Here we show that by using partially compressed tetrahedral clusters with retracted sticky patches, colloidal cubic diamond can be self-assembled using patch-patch adhesion in combination with a steric interlock mechanism that selects the required staggered bond orientation. Photonic bandstructure calculations reveal that the resulting lattices (direct and inverse) have promising optical properties, including a wide and complete photonic bandgap. The colloidal particles in the self-assembled cubic diamond structure are highly constrained and mechanically stable, which makes it possible to dry the suspension and retain the diamond structure. This makes these structures suitable templates for forming high-dielectric-contrast photonic crystals with cubic diamond symmetry.

13.
Langmuir ; 36(13): 3583-3589, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32054262

RESUMO

DNA-mediated colloidal interactions provide a powerful strategy for the self-assembly of ordered superstructures. We report a practical and efficient two-step chemical method to graft DNA brushes onto carboxylated particles, which resolves the previously reported issues such as irreversible aggregation, inhomogeneous coating, and relatively low DNA density that can hinder colloidal crystallization. First, carboxylated particles are functionalized with heterobifunctional poly(ethylene glycol) (NH2-PEGn-N3) by 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMTMM)-activated esterification of carboxylic groups and amide coupling. Then, dibenzocyclooctyne (DBCO)-functionalized DNA strands are grafted onto the pegylated particles through strain-promoted alkyne-azide cycloaddition (SPAAC) on azide groups. The homogeneous PEG brushes provide dispersion stability to the particles and clickable functional groups, resulting in DNA coatings of 1 100 000 DNA per 1 µm particle or 1 DNA per 2.9 nm2, about five times higher than previously reported. The DNA-coated particles exhibit a sharp association-dissociation transition and readily self-assemble into colloidal crystals upon annealing. In addition, fluorinated particles and lens-shaped particles with carboxylate groups are successfully grafted with DNA strands in this manner. Janus particles are also functionalized with DNA strands selectively on one of the two faces. Owing to the anisotropic attraction, the DNA-coated Janus particles self-assemble into self-limiting aggregates.


Assuntos
Azidas , Coloides , Alcinos , Reação de Cicloadição , DNA
14.
Angew Chem Int Ed Engl ; 56(20): 5507-5511, 2017 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-28402010

RESUMO

A facile method to synthesize shape-shifting patchy particles on the colloidal scale is described. The design is based on the solvent-induced shifting of the patch shape between concave and convex features. The initial concave patchy particles were synthesized in a water suspension by a swelling-induced buckling process. Upon exposure to different solvents, the patches were tuned reversibly to be either concave or convex. These particles can be assembled into chained, branched, zigzag, and cyclic colloidal superstructures in a highly site-specific manner by surface-liquid capillary bridging. The biphasic nature of the particles also enables site-selective surface functionalization.

15.
Nat Mater ; 16(6): 652-657, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28250446

RESUMO

Self-assembly is a powerful approach for constructing colloidal crystals, where spheres, rods or faceted particles can build up a myriad of structures. Nevertheless, many complex or low-coordination architectures, such as diamond, pyrochlore and other sought-after lattices, have eluded self-assembly. Here we introduce a new design principle based on preassembled components of the desired superstructure and programmed nearest-neighbour DNA-mediated interactions, which allows the formation of otherwise unattainable structures. We demonstrate the approach using preassembled colloidal tetrahedra and spheres, obtaining a class of colloidal superstructures, including cubic and tetragonal colloidal crystals, with no known atomic analogues, as well as percolating low-coordination diamond and pyrochlore sublattices never assembled before.

16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(4): 1090-3, 2012 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-22715791

RESUMO

In the present work, CdS quantum dots (QDs) were successfully biosynthesized at room temperature by using saccharomyces cerevisiae yeast as a carrier. Fluorescence emission spectra, ultraviolet-visible (UV/Vis) absorption spectra, and inverted fluorescence microscope images confirmed that saccharomyces cerevisiae can be used to biosynthesize CdS QDs. The as-prepared CdS QDs show the fluorescence emission peak at 443 nm and emit blue-green fluorescence under UV light (with excitation at 365 nm). Transmission electron microscopy (TEM) was applied to characterize the as-prepared CdS QDs and the TEM results showed that the as-prepared CdS QDs had the structure of hexagonal wurtzite. Fluorescence emission spectrum and UV/Vis absorption spectrum were used as the performance indicatiors to study the effects of saccharomyces cerevisiae yeast incubation times, reactant Cd2+ concentrations and reaction times on CdS QDs synthesis. Saccharomyces cerevisiae yeast grown in early stable phase can get the highest fluorescence intensity of CdS QDs when they were co-cultured with 0.5 mmol x L(-1) of Cd2+ with 24 h incubation time. Furthermore, much more CdS QDs can be obtained by changing the culture medium during the synthesis process.


Assuntos
Compostos de Cádmio/metabolismo , Pontos Quânticos/metabolismo , Saccharomyces cerevisiae/metabolismo , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Espectrometria de Fluorescência
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