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1.
Comput Struct Biotechnol J ; 23: 2388-2406, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38882682

RESUMO

Antimicrobial peptides are promising therapeutic agents for treating drug-resistant bacterial disease due to their broad-spectrum antimicrobial activity and decreased susceptibility to evolutionary resistance. In this study, three novel cathelicidin antimicrobial peptides were identified from Thamnophis sirtalis, Balaenoptera musculus, and Lipotes vexillifer by protein database mining and sequence alignment and were subsequently named TS-CATH, BM-CATH, and LV-CATH, respectively. All three peptides exhibited satisfactory antibacterial activity and broad antibacterial spectra against clinically isolated E. coli, P. aeruginosa, K. pneumoniae, and A. baumannii in vitro. Among them, TS-CATH displayed the best antimicrobial/bactericidal activity, with a rapid elimination efficiency against the tested drug-resistant gram-negative bacteria within 20 min, and exhibited the lowest cytotoxicity toward mammalian cells. Furthermore, TS-CATH effectively enhanced the survival rate of mice with ceftazidime-resistant E. coli bacteremia and promoted wound healing in meropenem-resistant P. aeruginosa infection. These results were achieved through the eradication of bacterial growth in target organs and wounds, further inhibiting the systemic dissemination of bacteria and the inflammatory response. TS-CATH exhibited direct antimicrobial activity by damaging the inner and outer membranes, resulting in leakage of the bacterial contents at super-MICs. Moreover, TS-CATH disrupted the bacterial respiratory chain, which inhibited ATP synthesis and induced ROS formation, significantly contributing to its antibacterial efficacy at sub-MICs. Overall, TS-CATH has potential for use as an antibacterial agent.

2.
Soft Matter ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38904343

RESUMO

The fabrication of stimulus-responsive supramolecular hydrogels as smart materials has attracted much attention in recent years. However, the multi-stimuli responsiveness often requires complicated chemical synthesis and rational molecular design. Herein, a quadruple-stimuli responsive supramolecular hydrogel was designed through the host-guest interaction between a ß-CD dimer and a methoxy-azobenzene (mAzo) and ferrocene (Fc) grafted poly(acrylic acid) derivative, as well as through the electrostatic interaction of negatively charged carboxyl side groups. Owing to the dynamic properties of the host-guest and electrostatic interactions, reversible sol-gel transition can be triggered by various stimuli, including temperature, light irradiations, pH changes and chemical redox reagents. As a result, the release of rhodamine B loaded in the hydrogel can be accelerated by green light irradiation, oxidizing agents and low pH, demonstrating potential applications in biomedical materials.

3.
Arch Virol ; 169(6): 130, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807015

RESUMO

Qingke Pingchuan granules (QPGs), which contain Houttuynia cordata Thunb, Fritillaria cirrhosa, fired licorice, and fired bitter almonds, among other components, can clear heat and ventilate the lungs, relieving cough and asthma. Clinically, QPGs are mainly used to treat cough, asthma, fever and other discomforts caused by acute or chronic bronchitis. In this study, the antiviral activity of QPGs against respiratory syncytial virus (RSV), influenza A virus A/FM/1/47 (H1N1), oseltamivir-resistant H1N1, A/Beijing/32/92 (H3N2), Sendai virus, and human adenovirus type 3 in Hep-2 or MDCK cells was evaluated using the CCK-8 method, and the cytotoxicity of QPGs to these two cell lines was tested. The effect of QPGs on mice infected with influenza A virus A/FM/1/47 (H1N1) was evaluated by measuring body weight, survival time, and survival rate, as well as virus titers and lesions in the lungs and levels of inflammatory factors in serum. In addition, the expression of TLR-7-My88-NF-κB signaling pathway-related proteins in lung tissues was analyzed by Western blotting and qRT-PCR. The results showed that QPGs had a potent inhibitory effect on the six viruses tested in vitro. Interestingly, QPGs also displayed particularly pronounced antiviral activity against H1N1-OC, similar to that of oseltamivir, a well-known antiviral drug. QPGs effectively protected mice from infection by H1N1, as indicated by significantly increased body weights, survival times, and survival rates and reduced lung virus titers of inflammatory factors and lung tissue injury. The levels of TLR-7-MyD88-NF-κB-pathway-related proteins in the lung tissue of infected mice were found to be decreased after QPG treatment, thereby alleviating lung injury caused by excessive release of inflammatory factors. Taken together, these findings indicate that QPGs have satisfactory activity against influenza virus infection.


Assuntos
Antivirais , Medicamentos de Ervas Chinesas , Vírus da Influenza A Subtipo H1N1 , Infecções por Orthomyxoviridae , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Camundongos , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/virologia , Cães , Células Madin Darby de Rim Canino , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/fisiologia , Camundongos Endogâmicos BALB C , Pulmão/virologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Linhagem Celular , Houttuynia/química , Influenza Humana/tratamento farmacológico , Influenza Humana/virologia , NF-kappa B/metabolismo , Feminino , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/fisiologia
4.
Angew Chem Int Ed Engl ; 63(24): e202402312, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38578652

RESUMO

The finite periodic arrangement of functional nanomaterials on the two-dimensional scale enables the integration and enhancement of individual properties, making them an important research topic in the field of tuneable nanodevices. Although layer-controllable lattices such as graphene have been successfully synthesized, achieving similar control over colloidal nanoparticles remains a challenge. DNA origami technology has achieved remarkable breakthroughs in programmed nanoparticle assembly. Based on this technology, we proposed a hierarchical assembly strategy to construct a universal DNA origami platform with customized layer properties, which we called 2.5-dimensional (2.5D) DNA origami crystals. Methodologically, this strategy divides the assembly procedure into two steps: 1) array synthesis, and 2) lattice synthesis, which means that the layer properties, including layer number, interlayer distance, and surface morphology, can be flexibly customized based on the independent designs in each step. In practice, these synthesized 2.5D crystals not only pioneer the expansion of the DNA origami crystal library to a wider range of dimensions, but also highlight the technological potential for templating 2.5D colloidal nanomaterial lattices.


Assuntos
DNA , DNA/química , Nanoestruturas/química , Tamanho da Partícula , Cristalização , Propriedades de Superfície , Conformação de Ácido Nucleico
5.
Clin Ophthalmol ; 18: 623-630, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481540

RESUMO

Purpose: To observe the outcome of bilateral femtosecond laser-assisted clear lens extraction with trifocal intraocular lens (IOL) implantation for presbyopia correction and evaluate its feasibility in early presbyopic adults. Methods: Prospective case series of eyes with clear crystalline lenses that underwent femtosecond laser-assisted lens extraction and trifocal IOL (Acrysof IQ PanOptix, Model TFNT00, Alcon) implantation between 2021 and 2023 were followed up for at least 3 months after surgery. Outcome measures included monocular uncorrected visual acuity at near (UNVA, 40 cm), intermediate (UIVA, 60 cm), and distance (UDVA, 5 m), monocular manifest refraction, corrected distance visual acuity (CDVA), defocus curve assessment, and spectacle independence at both near and distance. Results: A total of 60 eyes from 30 consecutive patients were included, and their mean age was 50.4±6.5 years. After surgery, the mean UNVA (LogMAR) increased from 0.28±0.16 to 0.08±0.07, UIVA increased from 0.25±0.12 to 0.09±0.06, and UDVA increased from 0.27±0.21 to 0.01±0.08. The enhancements of UNVA, UIVA and UDVA were all significant (P < 0.05). The optometric results showed that the mean postoperative spherical equivalent (SE) was -0.21±0.24 D, and the mean postoperative CDVA (LogMAR) was -0.00±0.06. The preoperative spectacle independences at near and distance were 46.7% (14/30) and 56.7% (17/30), respectively, and both increased to 100% at 3 months after surgery. Conclusion: Satisfactory visual outcomes and safe surgical procedures were observed in this study, which demonstrate that bilateral femtosecond laser-assisted clear lens extraction with PanOptix IOL implantation could be a feasible approach for presbyopia correction in working-age Chinese patients.

6.
Langmuir ; 40(13): 7158-7167, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38517397

RESUMO

Luminescent metal-organic gels (LMOGs) have gained much attention due to their crucial role in visual recognition and information encryption. However, it is still a challenge to simplify the design of ligands and enrich the stimuli responses in LMOGs simultaneously. Herein, although a single pyridine ligand cannot form gel alone, after coordination with metal ions, two kinds of LMOGs have been obtained with pyridine-metal complexes, where metal ions can act as cogelators and regulate luminescence of the pyridine-functionalized cyanostilbene ligand at the same time. The effects of metal types on the fluorescence emission color, the fluorescence quantum yield, the fibril network, and the assembly mode of the gel have been investigated systematically. In addition, two competitive ligands were used to regulate the fluorescence and phase transition of the gel. Finally, the logic gates and the information encryption and decryption have been successfully constructed. This kind of material is expected to be applied to fluorescence display, advanced information encryption, high-tech anticounterfeit, and so forth.

7.
Sensors (Basel) ; 24(5)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38474909

RESUMO

Simultaneous Localization and Mapping (SLAM), as one of the core technologies in intelligent robotics, has gained substantial attention in recent years. Addressing the limitations of SLAM systems in dynamic environments, this research proposes a system specifically designed for plant factory transportation environments, named GY-SLAM. GY-SLAM incorporates a lightweight target detection network, GY, based on YOLOv5, which utilizes GhostNet as the backbone network. This integration is further enhanced with CoordConv coordinate convolution, CARAFE up-sampling operators, and the SE attention mechanism, leading to simultaneous improvements in detection accuracy and model complexity reduction. While mAP@0.5 increased by 0.514% to 95.364, the model simultaneously reduced the number of parameters by 43.976%, computational cost by 46.488%, and model size by 41.752%. Additionally, the system constructs pure static octree maps and grid maps. Tests conducted on the TUM dataset and a proprietary dataset demonstrate that GY-SLAM significantly outperforms ORB-SLAM3 in dynamic scenarios in terms of system localization accuracy and robustness. It shows a remarkable 92.59% improvement in RMSE for Absolute Trajectory Error (ATE), along with a 93.11% improvement in RMSE for the translational drift of Relative Pose Error (RPE) and a 92.89% improvement in RMSE for the rotational drift of RPE. Compared to YOLOv5s, the GY model brings a 41.5944% improvement in detection speed and a 17.7975% increase in SLAM operation speed to the system, indicating strong competitiveness and real-time capabilities. These results validate the effectiveness of GY-SLAM in dynamic environments and provide substantial support for the automation of logistics tasks by robots in specific contexts.

8.
Chemistry ; 30(20): e202304366, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38296805

RESUMO

Photoswitching of photoluminescence has sparked tremendous research interests for super-resolution imaging, high-security-level anti-counterfeiting, and other high-tech applications. However, the excitation of photoluminescence is usually ready to trigger the photoswitching process, making the photoluminescence readout unreliable. Herein, we report a new photoswitch by the marriage of spiropyran with platinum(II) coordination complex. Viable photoluminescence can be achieved upon excitation by 480 nm visible light while the photoswitching can be easily triggered by 365 nm UV light. The feasible photoswitching may be benefited from the formed liquid crystalline (LC) phase of the designed photoswitch as a crystalline spiropyran is normally unable to implement photoswitching. Compared to the counterparts, this LC photoswitch can show distinct and reliable apparent colors and emission colors before and after photoswitching, which may promise the utility in high-security-level anti-counterfeiting and other advanced information technologies.

9.
Angew Chem Int Ed Engl ; 63(4): e202315061, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-37966368

RESUMO

The development of multimode photopatterning systems based on supramolecular coordination complexes (SCCs) is considerably attractive in supramolecular chemistry and materials science, because SCCs can serve as promising platforms for the incorporation of multiple functional building blocks. Herein, we report a light-responsive liquid-crystalline metallacycle that is constructed by coordination-driven self-assembly. By exploiting its fascinating liquid crystal features, bright emission properties, and facile photocyclization capability, a unique system with spatially-controlled fluorescence-resonance energy transfer (FRET) is built through the introduction of a photochromic spiropyran derivative, which led to the realization of the first example of a liquid-crystalline metallacycle for orthogonal photopatterning in three-modes, namely holography, fluorescence, and photochromism.

10.
Microbiol Spectr ; 12(1): e0099523, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38018988

RESUMO

IMPORTANCE: S. pneumoniae is a major human pathogen that undergoes a spontaneous and reversible phase variation that allows it to survive in different host environments. Interestingly, we found hsdSA , a gene that manipulated the phase variation, promoted the survival and replication of S. pneumoniae in macrophages by regulating EV production and EV-associated PLY. More importantly, here we provided the first evidence that higher EV-associated PLY (produced by D39) could form LAPosomes that were single membrane compartments containing S. pneumoniae, which are induced by integrin ß1/NOX2/ROS pathway. At the same time, EV-associated PLY increased the permeability of lysosome membrane and induced an insufficient acidification to escape the host killing, and ultimately prolonged the survival of S. pneumoniae in macrophages. In contrast, lower EV-associated PLY (produced by D39ΔhsdSA ) activated ULK1 recruitment to form double-layered autophagosomes to eliminate bacteria.


Assuntos
Streptococcus pneumoniae , Estreptolisinas , Humanos , Streptococcus pneumoniae/genética , Estreptolisinas/genética , Proteínas de Bactérias/genética , Macrófagos/metabolismo
11.
Eur J Med Chem ; 264: 115979, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38048696

RESUMO

Although no longer a public health emergency of international concern, COVID-19 remains a persistent and critical health concern. The development of effective antiviral drugs could serve as the ultimate piece of the puzzle to curbing this global crisis. 3-chymotrypsin-like protease (3CLpro), with its substrate specificity mirroring that of the main picornavirus 3C protease and conserved across various coronaviruses, emerges as an ideal candidate for broad-spectrum antiviral drug development. Moreover, it holds the potential as a reliable contingency option to combat emerging SARS-CoV-2 variants. In this light, the approved drugs, promising candidates, and de-novo small molecule therapeutics targeting 3CLpro since the COVID-19 outbreak in 2020 are discussed. Emphasizing the significance of diverse structural characteristics in inhibitors, be they peptidomimetic or nonpeptidic, with a shared mission to minimize the risk of cross-resistance. Moreover, the authors propose an innovative optimization strategy for 3CLpro reversible covalent PROTACs, optimizing pharmacodynamics and pharmacokinetics to better prepare for potential future viral outbreaks.


Assuntos
COVID-19 , Humanos , Quimases , SARS-CoV-2 , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Surtos de Doenças , Antivirais/farmacologia , Antivirais/química
12.
Case Rep Ophthalmol Med ; 2023: 7367922, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38022731

RESUMO

Background: To report the outcomes of phacoemulsification combined with vitrectomy in eyes with extreme myopia (-30 diopters or more). Case Presentation. Three patients with cataract, vitreous opacities, and extreme myopia of more than -30 diopters underwent a combined surgical procedure of cataract extraction combined with vitrectomy. Postoperative refractive correction of the three cases ranged from -1.0 D to -2.5 D spherical equivalent. There was an obvious hyperopic shift of all cases. All patients noted a significant improvement in uncorrected and best-corrected visual acuity from 0.4 to 0.8 in case 1, from CF/70 cm to 1.0 in case 2, and from 0.12 to 0.5 in the right eye and 0.15 to 0.2 in the left eye in case 3. Vitreous floaters disappeared in all cases. No complications were noted during follow-up. Conclusions: To the best of the authors' knowledge, these represent the first reported clinical cases of combined cataract extraction+vitrectomy surgery in eyes with extreme (>-30 D) myopia. Our results support the notion that phacoemulsification combined with vitrectomy may be a good therapeutic option for cataracts and vitreous floaters in cases with extreme myopia.

13.
Angew Chem Int Ed Engl ; 62(50): e202315911, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37905301

RESUMO

Accidentally, it was found that triphenylamine (TPA) from commercial sources shows ultralong yellow-green room temperature phosphorescence (RTP) like commercial carbazole, which however disappears for lab-synthesized TPA with high purity. Herein, we for the first time identify the impurity types that cause RTP of commercial TPA, which are two N, N-diphenyl-naphthylamine isomers. Due to similar molecular polarity and very trace amount (≈0.8 ‰, molar ratio), these naphthyl substituted impurities can be easily overlooked. We further show that even at an extremely low amount (1000000 : 1, mass ratio) of impurities, RTP emission is still generated, attributed to the triplet-to-triplet energy transfer mechanism. Notably, this doping strategy is also applicable to the triphenylphosphine and benzophenone host systems, of which strong RTP emission can be activated by simply doping the corresponding naphthyl substituted analogues into them. This work therefore provides a general and efficient host/guest strategy toward high performance and diverse organic RTP materials.

14.
J Colloid Interface Sci ; 652(Pt A): 997-1005, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37639930

RESUMO

The adsorption-catalysis synergy for accelerated conversion of polysulfides is critical toward the electrochemical stability of lithium-sulfur battery (LSB). Herein, a non-metallic polymer network with anion receptor units, trifluoromethanesulfonyl (CF3SO2-) substituted aza-ether, was in-situ integrated on PE separator, working as an efficient host for anchoring lithium thiophosphates (LPS) as redox mediators and polysulfides through Lewis acid-base interaction. The anchored LPS on the modified PE separator displayed a robust chemical adsorption ability towards polysulfides through the formation of SS bond. Meanwhile, LPS decreased the energy barrier of Li2S nucleation and promoted redox reaction kinetics. The battery with LPS decorated separator revealed a long cycling lifespan with a per cycle decay of 0.056 % after 600 cycles, and a competitive initial capacity of 889.1 mAh/g when the of sulfur cathode increased to 3 mg cm-2. This work developed a new design strategy to promote the utilization of lithium phosphorus sulfide compounds in LSB.

15.
Eur J Med Chem ; 259: 115653, 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37531743

RESUMO

The emergence of drug-resistant strains presents a grave challenge for traditional antibiotics, underscoring the exigency of exploring novel antibacterial drugs. To address this, the present study endeavors to design and synthesize a collection of pleuromutilin aromatic acrylate derivatives, guided by combination principles. The antibacterial activity and structure-activity relationship of these derivatives were evaluated, and most of the derivatives displayed moderate to excellent antibacterial activity against both Gram-positive bacteria and Gram-negative bacteria. Among these derivatives, 5g exhibited the strongest antibacterial activity, with MIC (minimum inhibitory concentration) values ranging from 1-32 µg/mL, and a MIC value against clinically isolated drug-resistant strains of 4-64 µg/mL. Additionally, 5g exhibited negligible cytotoxicity, superior anti-mycoplasma activity, and a greater propensity to perturb bacterial cell membranes. Notably, the administration of 5g resulted in an increased survival rate of MRSA (Methicillin-resistant Staphylococcus aureus)-infected mice, with an ED50 (median effective dose) value of 9.04 mg/kg. These results indicated the potential of 5g to be further developed as an antibacterial drug for the clinical treatment of drug-resistant bacterial infections.


Assuntos
Diterpenos , Staphylococcus aureus Resistente à Meticilina , Animais , Camundongos , Antibacterianos/farmacologia , Diterpenos/farmacologia , Diterpenos/uso terapêutico , Testes de Sensibilidade Microbiana , Bactérias Gram-Negativas , Pleuromutilinas
16.
Mol Med ; 29(1): 98, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37464341

RESUMO

BACKGROUND: Diabetic peripheral neuropathy (DPN) is a major complication of diabetes. This study aimed to investigate the therapeutic effects and molecular mechanisms of Compound Qiying Granules (CQYG) for DPN. METHODS: Rats and RSC96 cells of DPN models were established to evaluate the therapeutic effects of CQYG. Then the morphology and apoptotic changes of sciatic nerves were detected. Further, tandem mass tag based quantitative proteomics technology was used to identify differentially expressed proteins (DEPs) and the underlying molecular mechanisms. Protein expression of key signaling pathways was also detected. RESULTS: CQYG treatment significantly improved blood glucose and oxidative stress levels, and further reduced nerve fiber myelination lesions, denervation, and apoptosis in DPN rats. Further, 2176 DEPs were found in CQYG treated DPN rats. Enrichment analysis showed that protein processing in the endoplasmic reticulum (ER), and apoptosis were all inhibited after CQYG treatment. Next, CQYG treatment reduced inflammatory factor expression, mitochondrial damage, and apoptosis in RSC96 cells which induced by high glucose. Transmission electron microscopy results found that CQYG treatment improved the morphology of nerve myelin, mitochondria, and ER. CQYG treatment decreased ER stress and apoptosis pathway proteins that were highly expressed in DPN models. In addition, we also predicted the potential targets of CQYG in DEPs. CONCLUSIONS: CQYG exerts neuroprotective effects in experimental diabetic neuropathy through anti-ER stress and anti-apoptosis.


Assuntos
Diabetes Mellitus , Neuropatias Diabéticas , Ratos , Animais , Neuropatias Diabéticas/tratamento farmacológico , Neuropatias Diabéticas/patologia , Ratos Sprague-Dawley , Estresse do Retículo Endoplasmático/fisiologia , Bainha de Mielina , Transdução de Sinais , Nervo Isquiático
17.
Microbiol Res ; 275: 127447, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37441843

RESUMO

Soil amino acids (AAs) are the most active components of soil N, which can be mineralized or absorbed by bacteria as N and C sources. We hypothesized that exogenous AAs could regulate the bacterial community and affect soil N cycling, and the effect sizes could vary depending on individual AAs. Here, we applied feather (keratin)-based compost rich in AAs to Poncirus trifoliata (L.) to evaluate the regulation of bacterial community by AAs; furthermore, we applied six individual AAs to test their effects. The compost significantly increased soil hydrolysable AA content, ammonia monooxygenase gene abundance, and plant growth and changed bacterial community structure. Redundancy analysis revealed that the effects of AAs on the bacterial community composition were greater than those of soil chemical properties, and phenylalanine (Phe) was the most effective among thirteen individual AAs. When applied individually, Phe caused the greatest increase in N cycling-related enzyme activity and plant growth and most significantly altered the bacterial community structure among the six exogenous AAs. Notably, Phe significantly increased the relative abundances of Burkholderia-Caballeronia-Paraburkholderia, Azospirillum, Cupriavidus, and Achromobacter, whose abundances were significantly positively correlated with plant biomass, and significantly reduced the relative abundances of Arachidicoccus, Pseudopedobacter, Sphingobacterium, and Paenibacillus, whose abundances were significantly negatively correlated with plant biomass. We demonstrate that soil AAs strongly shape the bacterial community. Particularly, Phe enhances N cycling and plant growth by increasing the potentially beneficial bacterial taxa and inhibiting the potentially harmful bacterial taxa, which needs further validation.


Assuntos
Fenilalanina , Solo , Solo/química , Fenilalanina/metabolismo , Bactérias , Ciclo do Nitrogênio , Nitrogênio/metabolismo , Microbiologia do Solo
18.
Langmuir ; 39(31): 10904-10912, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37498220

RESUMO

In the design of effective gelators with aggregation-induced emission behavior, amide and cholesterol moieties are generally used to provide multiple driving forces for gelation. In this work, a series of linear cyanostilbene gelators with a pyridine moiety and different lengths of the alkoxyl group, i.e., CSpy-Cn, have been synthesized through nucleophilic substitution and Knoevenagel reaction. The direct connection of pyridine extends the conjugation of the cyanostilbene moiety, while the alkoxyl group can regulate the solubility of the compounds so that the compounds can serve as gelators for common solvents such as acetonitrile, dimethyl sulfoxide, and ethanol at ultra-low concentrations. At the same time, the cyanostilbene group makes the compounds undergo photoisomerization and emit fluorescence under UV light, while the pyridine group can serve as an acid-base responsive group due to easy protonation. The gels can respond to temperature, light, and organic acid/base. The fluorescence intensity and color can reversibly change during the gel-sol transitions. Finally, a thin film based on the CSpy-C8 xerogel has been prepared and utilized as a multi-stimuli-responsive fluorescence display for information storage and anti-counterfeiting.

19.
Peptides ; 166: 171040, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37295650

RESUMO

Cbf-14 with the sequence RLLRKFFRKLKKSV, is an effective antimicrobial peptide derived from a cathelin-like domain. Previous reports have demonstrated that Cbf-14 not only exerts antimicrobial activity against penicillin-resistant bacteria but also alleviates bacterial-induced inflammation in E. coli BL21 (DE3)-NDM-1-infected mice. In this article, we demonstrated that Cbf-14 can effectively reduce RAW 264.7 intracellular infection caused by clinical strain E. coli and alleviate the inflammatory response of cells and improve cell survival after infection. Therefore, we established the LPS-stimulated RAW 264.7 cell inflammation model to uncover the molecular mechanisms of the peptide Cbf-14 in anti-inflammatory activity. The results reveal that Cbf-14 can decrease LPS-induced ROS secretion by blocking the membrane translocation of p47-phox subunits and suppressing p47-phox protein phosphorylation. Meanwhile, this peptide can down-regulate the over-expression of iNOS, and finally inhibit the NO excessive secretion from RAW 264.7 macrophages stimulated by LPS. Moreover, Cbf-14 also down-regulates the expression levels of p-IκB and p-p65 and inhibits the nuclear translocation of NF-κB through blocking MAPK- and/or PI3K-Akt signaling pathways. Overall, Cbf-14 exhibits anti-inflammatory activity through inhibiting NF-κB activity and ROS production via PI3K- Akt signaling pathway.


Assuntos
NF-kappa B , Proteínas Proto-Oncogênicas c-akt , Animais , Camundongos , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Escherichia coli/metabolismo , Lipopolissacarídeos , Transdução de Sinais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Inflamação/metabolismo , Peptídeos/uso terapêutico , Óxido Nítrico
20.
Adv Mater ; 35(40): e2303680, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37381765

RESUMO

Recent years have witnessed the major advances of nanolights with extensive exploration of nano-luminescent materials like carbon dots (CDs). However, solvent-free processing of these materials remains a formidable challenge, impeding endeavors to develop advanced manufacturing techniques. Herein, in response to this challenge, liquid crystallization is demonstrated as a versatile and robust approach by deliberately anchoring flexible alkyl chains on the CDs surface. Alkyl chain grafting on the CDs surface is observed to substantially depress the common aggregation-caused quenching effect, and results in a shift of self-assembly structure from the crystalline phase to smectic liquid crystalline phase. The liquid-crystalline phase-transition temperature is ready to adjust by varying the alkyl chain length, endowing low-temperature (<50 °C) melt-processing capabilities. Consequently, the first case of direct ink writing (DIW) with liquid crystal (LC) carbon dots is demonstrated, giving rise to highly emissive objects with blue, green and red fluorescence, respectively. Another unexpected finding is that DIW with the LC inks dramatically outperforms DIW with isotropic inks, further highlighting the significance of the LC processing. The approach reported herein not only exhibits a fundamental advance by imparting LC functions to CDs, but also promises technological utility in DIW-based advanced manufacturing.

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