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1.
Small ; : e2401308, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773889

RESUMO

Incorporating ultralow loading of nanoparticles into polymers has realized increases in dielectric constant and breakdown strength for excellent energy storage. However, there are still a series of tough issues to be dealt with, such as organic solvent uses, which face enormous challenges in scalable preparation. Here, a new strategy of dual in situ synthesis is proposed, namely polymerization of polyethylene terephthalate (PET) synchronizes with growth of calcium borate nanoparticles, making polyester nanocomposites from monomers directly. Importantly, this route is free of organic solvents and surface modification of nanoparticles, which is readily accessible to scalable synthesis of polyester nanocomposites. Meanwhile, uniform dispersion of as ultralow as 0.1 wt% nanoparticles and intense bonding at interfaces have been observed. Furthermore, the PET-based nanocomposite displays obvious increases in both dielectric constant and breakdown strength as compared to the neat PET. Its maximum discharged energy density reaches 15 J cm-3 at 690 MV m-1 and power density attains 218 MW cm-3 under 150 Ω resistance at 300 MV m-1, which is far superior to the current dielectric polymers that can be produced at large scales. This work presents a scalable, safe, low-cost, and environment-friendly route toward polymer nanocomposites with superior capacitive performance.

2.
Anal Methods ; 16(14): 2085-2092, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38511545

RESUMO

This study proposes a microfluidic platform for rapid enrichment and ultrasensitive SERS detection of bacteria. The platform comprises ZnO nanoflower arrays decorated with silver nanoparticles to enhance the SERS sensitivity. The ZnO nanoflower array substrate with a 3D reticular columnar structure is prepared using the hydrothermal method. SEM analysis depicts the 3.05 µm gap distribution of the substrate array to intercept the most bacteria in the particle sizes range of 0.5 to 3 µm. Then, silver nanoparticles are deposited on the ZnO nano-array surface by liquid evaporation self-assembly. TEM and SEM analysis indicate nanosize of Ag particles, evenly distributed on the substrate, enhancing the SERS efficiency and improving sensing reproducibility. The probe molecules (R6G) are tested to demonstrate the high SERS activity of the proposed microfluidic sensor. Then, Escherichia coli, Staphylococcus aureus, Enterococcus faecalis, and Bacillus subtilis are selected, demonstrating the sensor's excellent bacterial capture and sensitive recognition capabilities, with a detection limit as low as 102 CFU mL-1. Additionally, the antibacterial properties of ZnO/Ag heterojunction nanostructures are studied, suggesting their ability to inactivate bacteria. Compared with the traditional Au-enhanced chip, the sensor preparation is easy, safe, reliable, and low-cost. Moreover, the ZnO nano-array exhibits a large specific surface area, high interception ability, stronger and uniform SERS performance, and effective and reliable detection of trace pathogens. This work provides potential future ZnO/Ag microfluidic SERS sensor applications for rapid, unlabeled, and trace pathogens detection in clinical and environmental applications, potentially achieving breakthroughs in early detection, prevention, and treatment.


Assuntos
Nanopartículas Metálicas , Óxido de Zinco , Prata/química , Óxido de Zinco/química , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes , Microfluídica , Bactérias
3.
Environ Res ; 241: 117653, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37980982

RESUMO

When confronted with wastewater that is characterized by complex composition, stable molecular structure, and high concentration, relying solely on photocatalytic technology proves inadequate in achieving satisfactory degradation results. Therefore, the integration of other highly efficient degradation techniques has emerged as a viable approach to address this challenge. Herein, a novel strategy was employed whereby the exfoliated g-C3N4 nanosheets (CNs) with exceptional photocatalytic performance, were intimately combined with porous rod-shaped cobalt ferrite (CFO) through a co-calcination process to form the composite CFO/CNs, which exhibited remarkable efficacy in the degradation of various organic pollutants through the combination of photocatalysis and Fenton-like process synergistically, exemplified by the representative case of tetracycline hydrochloride (TCH, 200 mL, 50 mg/L). Specifically, under 1 mM of peroxymonosulfate (PMS) and illumination conditions, 50 mg of 1CFO/9CNs achieved a TCH removal ratio of ∼90% after 60 min of treatment. Furthermore, this work comprehensively investigated the influence of various factors, including catalyst and PMS dosages, solution pH, and the presence of anions and humate, on the degradation efficiency of pollutants. Besides, quenching experiments and EPR tests confirmed the establishment of an S-scheme heterojunction between CNs and CFO, which facilitated the effective spatial separation of photoexcited charge carriers and preserved the potent redox potential of photogenerated electrons and holes. This work offers a valuable reference for the integration of photocatalysis with the PMS-based Fenton-like process.


Assuntos
Elétrons , Poluentes Ambientais , Porosidade , Iluminação
4.
Appl Radiat Isot ; 198: 110862, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37235986

RESUMO

To explore the new iodine labeling method of nanomaterials, graphene oxide (GO) was labeled by 131I with AgI nanoparticles. As a control, GO was also labeled by 131I with chloramine-T method. The stability of the two 131I labeling materials, viz. [131I]AgI-GO and [131I]I-GO was evaluated. The results show that [131I]AgI-GO is very stable in inorganic environment such as PBS and saline. However, it is not stable enough in serum. The instability of [131I]AgI-GO in serum can be attributed to the higher affinity of Ag to S of thiol group in cysteine than iodine ions and much more chance of interaction between thiol group and [131I]AgI nanoparticles on two-dimensional GO than in three-dimensional nanomaterials.


Assuntos
Iodo , Nanopartículas , Cisteína
5.
Front Physiol ; 14: 1097317, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36814477

RESUMO

In general, insects grow (increase in body size) through molting. To the opposite, the body size of the males of the horned gall aphid, Schlechtendalia chinensis, gets smaller after molting and as they age. To understand the molecular bases of this rare phenomenon, transcriptomes were generated from 1-5 days old male and the data were analyzed via a weighted gene co-expression network analysis (WGCNA). A total of 15 partitioned modules with different topological overlaps were obtained, and four modules were identified as highly significant for male body length (p < 0.05). Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis suggested that a portion of genes in the four modules are likely involved in autophagy and apoptosis. In addition, a total of 40 hub genes were obtained in the four modules, and among them eight genes were highly expressed in males compared to individuals of other generations of S. chinensis. These eight genes were associated with autophagy and apoptosis. Our results reveal the unique negative growth phenomenon in male S. chinensis after molting, and also suggest that the male S. chinensis with no ability to feed probably decompose their own substances via autophagy and apoptosis to provide energy for life activities such as germ cell development.

6.
J Hazard Mater ; 443(Pt B): 130326, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36444054

RESUMO

Reasonable regulation of the micro-morphology of material can significantly enhance the related performance. Herein, bismuth tungstate (Bi2WO6, simplified as BWO) porous hollow spheres with flower-like surface were prepared successfully, and this unique morphology endowed BWO with improved photocatalytic performance by reflecting and absorbing the light multiple times inside the cavity. To inhibit the rapid recombination of photogenerated e--h+ pairs within BWO itself, black phosphorous quantum dots (BPQDs) were anchored onto the nanosheets of BWO sphere closely by a facile self-assembly process, which will not shade the pores of BWO owing to the small size of BPQDs, but the BP nanosheets have the chance to do that. The band gap of BPQDs expanded much after exfoliation due to the quantum confinement effects, which matched the energy band of BWO well to form S-scheme heterojunction, achieving more efficient separation of photogenerated charges. As a result, the BPQDs/BWO exhibited attractive photocatalytic performance in the degradation of amoxicillin (AMX) and other antibiotics. Besides, the operation conditions were optimized, specifically, 94.5 % of AMX (20 mg/L, 200 mL) can be removed in 60 min when 50 mg of 2BPQDs/BWO was used as catalyst with solution pH = 11. Moreover, a possible degradation pathway of AMX was proposed based on the detected intermediates.


Assuntos
Amoxicilina , Pontos Quânticos , Fósforo , Porosidade , Luz
7.
J Environ Sci (China) ; 123: 367-386, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36521999

RESUMO

Emissions from mobile sources and stationary sources contribute to atmospheric pollution in China, and its components, which include ultrafine particles (UFPs), volatile organic compounds (VOCs), and other reactive gases, such as NH3 and NOx, are the most harmful to human health. China has released various regulations and standards to address pollution from mobile and stationary sources. Thus, it is urgent to develop online monitoring technology for atmospheric pollution source emissions. This study provides an overview of the main progress in mobile and stationary source monitoring technology in China and describes the comprehensive application of some typical instruments in vital areas in recent years. These instruments have been applied to monitor emissions from motor vehicles, ships, airports, the chemical industry, and electric power generation. Not only has the level of atmospheric environment monitoring technology and equipment been improving, but relevant regulations and standards have also been constantly updated. Meanwhile, the developed instruments can provide scientific assistance for the successful implementation of regulations. According to the potential problem areas in atmospheric pollution in China, some research hotspots and future trends of atmospheric online monitoring technology are summarized. Furthermore, more advanced atmospheric online monitoring technology will contribute to a comprehensive understanding of atmospheric pollution and improve environmental monitoring capacity.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Compostos Orgânicos Voláteis , Humanos , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Monitoramento Ambiental , Material Particulado/análise , Tecnologia , Emissões de Veículos/análise , Compostos Orgânicos Voláteis/análise
8.
Biomass Convers Biorefin ; : 1-14, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36536881

RESUMO

Intelligent single-layer packaging is widely used in food monitoring and storage. However, most single-layer intelligent packaging has poor mechanical strength and water barrier properties. In this study, a bilayer intelligent detector film based on polyvinyl alcohol-chitosan (PVA-CS)/nano-ZnO/sodium alginate (SA) combined with anthocyanin extract (cyanidin chloride) was prepared using a layer-by-layer solution casting assembly technique. The effects of different levels of anthocyanin extracts on the physical and functional properties of the films, including microstructure, mechanical property, barrier property, pH sensitivity, and antibacterial property, were investigated. The results show that the bilayers exhibit excellent physical properties, lower water vapor permeability, better light transmission and UV-blocking properties, a broader pH sensitivity (ΔE > 10), and good antibacterial activity. In short, the bilayer films studied are superior to the single-layer films in terms of their packaging potential for products with low moisture content, offering new directions for active intelligent packaging and biodegradable materials for the food industry.

9.
Curr HIV Res ; 2022 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-36089779

RESUMO

BACKGROUND: Studies have found that HIV is mainly transmitted through the mucosal surface, and the entrance of early progression of the disease is the rectal and colonic mucosa. So, this paper aimed to explore and analyze the structural differences of gut microbiome between men who have sex with men (MSM) and those who haven't sex with men (Non-MSM), expecting finding novel biological factors that potentially impact transmission and/or disease in MSM population. METHODS: We collected a total of 33 stool samples, 16 were MSM and 17 were Non-MSM. The 16S rRNA gene amplification sequencing was used to detect the alteration and structure of the gut microbiome community in two groups. RESULTS: The difference in ß diversity of gut microbiome of two groups of subjects was statistically significant (P<0.001), indicating that the difference in the structure of the gut microbiome of two groups was statistically significant. Compared with the phylum and genus level of Non-MSM group, the relative abundances of Actinobacteria, Proteobacteria, genera Collinsella, Prevotella, Bifidobacterium and Ralstonia in MSM group were higher (P<0.001, P<0.05, LDA score(log10)>2), and the relative abundance of Bacteroidetes, genera Erysipelotrichaceae incertae sedis, Bilophila, Holdemania, Clostridium XIVb and Bacteroidaceae in MSM group was lower (P<0.01, LDA score(log10)>2). CONCLUSIONS: There are some differences in the structure of gut microbiome between MSM group and Non-MSM group. It indicates the differences in behavior and characteristics between MSM and Non-MSM population may be related to the difference in the structure of gut microbiome.

10.
Ecol Evol ; 12(4): e8815, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35475184

RESUMO

The aphid Schlechtendalia chinensis is an economically important insect that can induce horned galls, which are valuable for the medicinal and chemical industries. Up to now, more than twenty aphid genomes have been reported. Most of the sequenced genomes are derived from free-living aphids. Here, we generated a high-quality genome assembly from a galling aphid. The final genome assembly is 271.52 Mb, representing one of the smallest sequenced genomes of aphids. The genome assembly is based on contig and scaffold N50 values of the genome sequence are 3.77 Mb and 20.41 Mb, respectively. Nine-seven percent of the assembled sequences was anchored onto 13 chromosomes. Based on BUSCO analysis, the assembly involved 96.9% of conserved arthropod and 98.5% of the conserved Hemiptera single-copy orthologous genes. A total of 14,089 protein-coding genes were predicted. Phylogenetic analysis revealed that S. chinensis diverged from the common ancestor of Eriosoma lanigerum approximately 57 million years ago (MYA). In addition, 35 genes encoding salivary gland proteins showed differentially when S. chinensis forms a gall, suggesting they have potential roles in gall formation and plant defense suppression. Taken together, this high-quality S. chinensis genome assembly and annotation provide a solid genetic foundation for future research to reveal the mechanism of gall formation and to explore the interaction between aphids and their host plants.

11.
Spectrochim Acta A Mol Biomol Spectrosc ; 270: 120818, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-34999358

RESUMO

The three-dimensional (3D) surface-enhanced Raman scattering (SERS) substrate for trace molecule detection has recently attracted considerable interest; however, these substrates generally either show poor sensitivity or require a complex preparation process. In this work, we have fabricated a 3D ZnO/Ag substrate using porous zeolite imidazole frameworks (ZIF-8) derived ZnO nanoparticles (NPs) followed by evaporation-induced self-assembly of Ag NPs over it, which can detect multiple environmental pollutants by a facile and cost-effective method. This 3D porous substrate showed an ultra-sensitivity for detecting various types of molecules, e.g., rhodamine 6G (R6G), crystal violet (CV), tetracycline, and thiram, simultaneously suggesting its generality. Notably, the lowest detectable concentration (LDC) attained for R6G is 10-13 M, and the enhancement factor (EF) reaches up to 1.8 × 108. The most important reason for ultra-sensitivity is that ZnO derived from ZIF-8 has a hierarchical porous structure and large surface area to provide more "hot spots" and absorb more probe molecules. Consequently, the ZnO/Ag nanostructures show excellent photocatalytic performance. The detected probe molecules could be completely degraded in situ within a short UV exposure time (<30 min), thereby enabling outstanding reusability of this substrate. Finite-different time-domain (FDTD) simulations were used to understand the underlying mechanism of the substrate by calculating electric fields and hot spot distributions. The simulations suggested that the widespread hot spots structures on the substrate are the main reason for its SERS ultra-sensitivity.


Assuntos
Poluentes Ambientais , Nanopartículas Metálicas , Nanoestruturas , Óxido de Zinco , Porosidade , Prata
12.
J Magn Reson ; 332: 107079, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34638086

RESUMO

During oil and gas exploration, it is difficult to quantitatively evaluate fluid components and accurately calculate the saturation of different fluids because of the overlapping of fluid components on 2D NMR spectrum. In this paper, Blind Source Separation (BSS) is proposed to separate fluid components, which utilizes the statistical independence of fluid signals on 2D NMR spectrum. Fast Independent Component Analysis (FastICA) is employed for the inverted NMR spectrums in an entire logged interval to obtain the residual information to determine the number of fluid components. Based on the determined number of fluid components, Nonnegative matrix factorization (NMF) is used to obtain the features of fluid components on NMR spectrum and the region on 2D NMR spectrum is divided into different regions. The overlapping regions are classified by distance or distance and T1/T2 to obtain the modified NMR spectrum. Through T2-D and T1-T2 numerical simulation, the fluid saturations calculated by the proposed method and NMF are compared to verify the effectiveness of the proposed method. The results showed that the proposed method can be used to determine the number of fluid components effectively, and the calculated fluid saturations are more accurate than that obtained by NMF.

13.
ACS Appl Mater Interfaces ; 13(34): 41012-41020, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34410119

RESUMO

Photodynamic therapy (PDT) is a potential approach to resolve antibiotic resistance, and phenylene/thiophene-ethynylene oligomers have been widely studied as effective antibacterial reagents. Oligomers with thiophene moieties usually exhibit good antibacterial activity under light irradiation and dark conditions. In the previous study, we verified that neutral oligo-p-phenylene-ethynylenes (OPEs) exhibit better antibacterial activity than the corresponding cationic ones; however, whether this regular pattern also operates in other kinds of oligomers such as oligo-thiophene-ethynylene (OTE) is unknown. Also, the antibacterial activity comparison of OTEs bearing cyclic and acyclic amino groups will offer useful information to further understand the role of amino groups in the antibacterial process and guide the antibacterial reagent design as amino groups affect the antibacterial activity a lot. We synthesized four OTEs bearing neutral or cationic, cyclic, or acyclic amino groups and studied their antibacterial activity in detail. The experimental results indicated that the OTEs exhibited better antibacterial activity than the OPEs, the neutral OTEs exhibited better antibacterial activity in most cases, and OTEs bearing cyclic amino groups exhibited better antibacterial activity than those bearing acyclic ones in most cases. This study provides useful guidelines for further antibacterial reagent design and investigations.


Assuntos
Alcinos/farmacologia , Antibacterianos/farmacologia , Tiofenos/farmacologia , Alcinos/química , Alcinos/efeitos da radiação , Alcinos/toxicidade , Antibacterianos/química , Antibacterianos/efeitos da radiação , Antibacterianos/toxicidade , Linhagem Celular , Escherichia coli/efeitos dos fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Luz , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos , Tiofenos/química , Tiofenos/efeitos da radiação , Tiofenos/toxicidade
14.
J Neural Transm (Vienna) ; 128(6): 717-734, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34115189

RESUMO

BACKGROUND: Based on recent evidence, more than 200 susceptibility genes have been identified to be associated with autism until now. Correspondingly, cytogenetic abnormalities have been reported for almost every chromosome. While the results of multiple genes associated with risk factors for autism are still incomplete, this paper systematically reviews published meta-analyses and systematic reviews of evidence related to autism occurrence. METHOD: Literature search was conducted in the PubMed system, and the publication dates were limited between January 2000 and July 2020. We included a meta-analysis and systematic review that assessed the impact of related gene variants on the development of autism. After screening, this comprehensive literature search identified 31 meta-analyses and ten systematic reviews. We arranged the genes related to autism in the published studies according to the order of the chromosomes, and based on the results of a meta-analysis and systematic review, we selected 6 candidate genes related to ASD, namely MTHFR C677T, SLC25A12, OXTR, RELN, 5-HTTLPR, SHANK, including basic features and functions. In addition to these typical genes, we have also listed candidate genes that may exist on almost every chromosome that are related to autism. RESULTS: We found that the results of several literature reviews included in this study showed that the MTHFR C667T variant was a risk factor for the occurrence of ASD, and the results were consistent. The results of studies on SLC25A12 variation (rs2056202 and rs2292813) and ASD risk were inconsistent but statistically significant. No association of 5-HTTLPR was found with autism, but when subgroup analysis was performed according to ethnicity, the association was statistically significant. RELN variants (rs362691 and rs736707) were consistent with ASD risk studies, but some of the results were not statistically significant. CONCLUSION: This review summarized the well-known ASD candidate genes and listed some new genes that need further study in larger sample sets to improve our understanding of the genetic basis of ASD, but sample size and heterogeneity remain major limiting factors in some genome-wide association studies. We also found that common genetic variants in some genes may be co-risk factors for autism or other neuropsychiatric disorders when we collated these results. It is worth considering screening for these mutations in clinical applications.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Transtorno do Espectro Autista/genética , Transtorno Autístico/genética , Estudo de Associação Genômica Ampla , Humanos , Metanálise como Assunto , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Proteína Reelina , Fatores de Risco , Revisões Sistemáticas como Assunto
15.
J Phys Chem B ; 125(12): 3230-3237, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33755475

RESUMO

In this work, the phase behavior of the poly(vinyl alcohol) (PVA)/alkyl ethoxysulfate (AES)/water ternary system is investigated at 25 °C. The PVA/AES/water ternary phase diagram is conducted which shows that there are two main phases corresponding to the solid phase and the hexagonal liquid crystalline phase (H) in the ternary system. Besides these two phases, a high-viscosity liquid phase (L2) and a micellar phase (L1) can also be found in the phase diagram, although they just occupy small areas. Polarizing optical microscopy and small-angle X-ray scattering are used to characterize the different lyotropic liquid crystal types. Moreover, the viscosity distribution and oscillation tests are also performed by means of the rheometer. High elastic modulus (G') and viscous modulus (G″) can be found in the H and the L2 phase, whereas both moduli are low in the L1 region. The PVA/AES/water ternary phase diagram provides a good guide for accelerating the selection of the detergent formula, whereas the rheological tests provide an application guidance for industrial operations. Beyond tis, the L1 region is considered to be a reasonable range for slurry making because of its good fluidity and low viscoelasticity. This research enriches the content of polymer-surfactant aggregates and promotes the development of solid detergent manufacturing industry.

16.
Eur J Pharm Sci ; 161: 105775, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33640501

RESUMO

Hyaluronan (HA) is a negatively charged linear polysaccharide that can interact with cluster determinant 44 (CD44) overexpressed cancers. However, HA can also bind to excess substrates in the human body leading to the lower specificity of tumor targeting. Conjugation of other targeting group to HA could enhance the uptake by cancer cell comparing to that of native HA. In this study, we develop the multi-functionalized HA (177Lu-DOTA/Alexa647-HA100-N) for malignant tumor targeting. An asparagine-glycine-arginine (NGR) based peptide was selected for HA functionalization. The peptide is known to target CD13 receptor that is overexpressed in malignant tumors with abundant blood vessels, such as lung cancer. Furthermore, the fluorescent probe Alexa Fluor 647 for ex vivo/in vivo tracking and the radionuclide 177Lu for radioactive therapy were both labeled on the material. The functionalized HA could be bound by lung cancer cells and breast cancer cells. In vivo fluorescent imaging showed that the material could accumulate in the tumor site for more than 96 h. The 177Lu labeling of functionalized HA was stable for more 48 h at physiological conditions. The accumulation of 177Lu-DOTA/Alexa647-HA100-N in the tumor of lung cancer (NCI-H292) bearing mice was 1.91±0.97%ID/g, and it was about 17 times higher than the value in blood. Conclusion: The multimodality labeled functional HA was successfully prepared and could be fluorescent trackable ex vivo and in vivo. It showed high potential to be used for malignant cancer radiotherapy for its specific targeting property to tumors and radiotoxicity from the labeled 177Lu radionuclide.


Assuntos
Ácido Hialurônico , Neoplasias Pulmonares , Animais , Linhagem Celular Tumoral , Neoplasias Pulmonares/radioterapia , Camundongos , Peptídeos , Radioisótopos
17.
ACS Appl Bio Mater ; 4(4): 3561-3570, 2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35014441

RESUMO

More strategies are required to develop better photosensitizers for photodynamic therapy (PDT). As oligo(phenylene-ethynylene) electrolytes (OPE), oligo(thiophene)s with primary amine as pendant groups (P-OT), and oligo(thiophene ethynylene) (OTE) exhibit excellent light-induced biocidal activity, we desire to converge the molecular design principles of these three kinds of antibacterial agents to combine their advantages to obtain high efficiency and economic biocides. Thus, four oligo(thiophene)s (OTs) were designed and synthesized in this study. The light-induced and dark antibacterial efficacy of the four OTs against Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) were both evaluated. Notably, all the OTs present high biocidal efficacy in the broad spectrum at low (micromolar) concentrations after white-light irradiation. In particular, the low cell cytotoxicity of OTs exhibits their good biocompatibility. These results illustrate that the OTs could work as promising PDT biocides. Interestingly, OT-3 shows a strong and specific dark killing activity against E. coli. The higher biocidal efficacy of T-OTs compared with that of Q-OTs confirms the tertiary amine is a better pendant group for π-conjugated antibacterial agents against E. coli. Mechanistic investigation proves ROS is the necessary element for antibiosis under white light. The interacting efficacy of the OT to the cell membrane, involving synergistic effects between hydrophilic-hydrophobic interactions and electrostatic attractions, is also critical in the killing process. The membrane intercalating activity plays a more essential role, as indicated by the antibacterial activity of OTs. The results provide a unique insight into the relationship between molecular structure and antibacterial activities of this class of antibacterial agents.


Assuntos
Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Escherichia coli/efeitos dos fármacos , Luz , Fotoquimioterapia , Tiofenos/farmacologia , Antibacterianos/química , Materiais Biocompatíveis/química , Teste de Materiais , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Staphylococcus aureus/efeitos dos fármacos , Tiofenos/química
18.
Carbohydr Polym ; 252: 117243, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33183650

RESUMO

Amylose granules hydrolyzed with 2 M hydrochloric acid for various periods of time were used to prepare amylose nanoparticles through ethanol precipitation. Value of dextrose equivalent, viscosity average molecular weight and molecular chain length distribution of the acid hydrolyzed amylose granules were determined. The precipitated amylose nanoparticles were characterized by using dynamic light scattering and X-ray diffraction. Results showed that, after 48 h acid hydrolysis, viscosity average molecular weight of amylose decreased from 3.35 × 105 to 0.336 × 105 and the amylose macromolecular chains with DP > 1000 were cut into short ones. The short chain sugar molecules derived from the acid hydrolysis were not involved in the ethanol precipitation or incorporated into the precipitated amylose nanoparticles. The length and quantity of the residual amylose macromolecular chains after the acid hydrolysis were the main factors to influence size and crystallinity of the precipitated amylose nanoparticles.


Assuntos
Amilose/química , Ácido Clorídrico/química , Nanopartículas/química , Precipitação Química , Etanol/química , Hidrólise , Peso Molecular , Viscosidade
19.
Chinese Journal of School Health ; (12): 1193-1197, 2021.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-886616

RESUMO

Objective@#To compare the reliability of Internet Addiction Impairment Index (IAII), Revised Chen Internet Addiction Scale(CIAS-R)-Taiwan Revision, CIAS-R-Mainland Revision, Young Diagnostic Questionnaire (YDQ) and the consistency of Internet addiction using the four scales in college students.@*Methods@#A total of 1 004 undergraduates from 3 universities in Hefei were selected to measure the tendency of internet addiction simultaneously using the four scales, and 122 students were re tested two weeks after the initial assessment. Correlation coefficient, coincidence rate and Kappa value were used to analyze the consistency of the four scales. Analysis of variance, t test and Logistic regression were used to determine the consistency of the factors related to internet addiction scale.@*Results@#The reliability of the four Internet addiction scales were greater than 0.7( P <0.01). The correlation coefficient among all scales was greater than 0.5( P <0.01). The agreement between YDQ and CIAS-R-Mainland Revision was 0.87. The Kappa value of YDQ and CIAS-R-Taiwan Revision in the consistency analysis was 0.51( P <0.01), the Kappa value between the other scales was less than 0.5. Results showed that the four scales were consistent in Internet addiction prevalence by gender, grade and major, while CIAS-R-Taiwan Revision and YDQ were not consistent with the other two scales in sleep disorder.@*Conclusion@#The four Internet addiction scales all have good reliability, while low agreement in Internet addiction assessment, suggesting further improvement and revision in Internet addiction scales.

20.
Mol Imaging ; 19: 1536012120934957, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32862776

RESUMO

Asn-Gly-Arg (NGR) motifs have vasculature-homing properties via interactions with the aminopeptidase N (CD13) expressed on tumor neovasculature. Numerous NGR peptides with different molecular scaffolds have been exploited for targeted delivery of different compounds for imaging and therapy. When conjugated with NGR, complexes recognize the CD13 receptor expressed on the tumor vasculature, which improves the specificity to tumor and avoids systematic toxic reactions. Both preclinical and clinical studies performed with these products suggest that NGR-mediated vascular targeting is an effective strategy for delivering bioactive amounts of cytokines to tumor endothelial cells. For molecular imaging, radiolabeled peptides have been the most successful approach and have been translated into clinic. This review describes current data on radiolabeled tumor vasculature-homing NGR peptides for imaging and therapy.


Assuntos
Pesquisa Biomédica , Oligopeptídeos/uso terapêutico , Compostos Radiofarmacêuticos/química , Animais , Sistemas de Liberação de Medicamentos , Humanos , Imagem Molecular , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico
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