Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 183
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
ACS Sens ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016238

RESUMO

Metal oxides with nanoarray structures have been demonstrated to be prospective materials for the design of gas sensors with high sensitivity. In this work, the WO3 nanoneedle array structures were synthesized by a one-step hydrothermal method and subsequent calcination. It was demonstrated that the calcination of the sample at 400 °C facilitated the construction of lilac-like multiple self-supporting WO3 arrays, with appropriate c/h-WO3 heterophase junction and highly oriented nanoneedles. Sensors with this structure exhibited the highest sensitivity (2305) to 100 ppm ethylene glycol at 160 °C and outstanding selectivity. The enhanced ethylene glycol gas sensing can be attributed to the abundant transport channels and active sites provided by this unique structure. In addition, the more oxygen adsorption caused by the heterophase junction and the aggregation of reaction medium induced by tip effect are both in favor of the improvement on the gas sensing performance.

2.
Int J Biol Macromol ; 276(Pt 1): 133777, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38996880

RESUMO

In this study, three types of dodecyl chitosan quaternary ammonium salts, each with different spacer groups were synthesized. These chitosan derivatives are N',N'-dimethyl-N'-dodecyl-ammonium chloride-N-amino-acetyl chitosan (DMDAC), N'-dodecyl-N-isonicotinyl chitosan chloride (DINCC) and N',N'-dimethyl-N'-dodecyl-ammonium chloride-N-benzoyl chitosan (DMDBC). The synthesized products were characterized using Fourier transform infrared spectrometers, nuclear magnetic resonance, thermogravimetric analysis, and elemental analysis. The antibacterial and antibiofilm activities against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were investigated. The experimental results indicated that the introduction of hydrophobic groups of spacer groups could enhance the antibacterial and antibiofilm activities of the chitosan derivatives. The antibacterial rates of the chitosan derivatives were over 90 % for both E. coli and S. aureus at a concentration of 0.5 mg/mL. The chitosan derivatives removed >50 % of the mature biofilm of E. coli and over 90 % of the mature biofilm of S. aureus at a concentration of 2.5 mg/mL. Further, the synthesized chitosan derivatives were determined to be non-toxic to L929 cells. Among them, DMDBC exhibited the most promising overall performance and show potential for wide-ranging applications in food preservation, disinfectants, medical, and other fields.

3.
Food Chem ; 455: 139908, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38850971

RESUMO

Chitosan quaternary phosphine salts (NPCS) were synthesized with enhanced antimicrobial properties using a two-step method. Composite films (CNSP) were prepared by incorporating NPCS and polyvinyl alcohol (PVA) as the base material, citric acid as the crosslinker and functional additive, exhibiting antibacterial and UV-blocking properties. The composite film showed a maximum tensile strength of 20.4 MPa, an elongation at break of 677%, and a UV light barrier transmittance of 70%. Application of these composite membranes in preserving strawberries demonstrated effectiveness in maintaining freshness by preventing water loss, inhibiting microbial growth, and extending shelf life. In addition, the composite film demonstrated biosafety. These results indicate that CNSP composite films holds significant promise for safe and sustainable food packaging applications.


Assuntos
Quitosana , Ácido Cítrico , Embalagem de Alimentos , Conservação de Alimentos , Fragaria , Álcool de Polivinil , Álcool de Polivinil/química , Fragaria/química , Quitosana/química , Quitosana/farmacologia , Ácido Cítrico/química , Ácido Cítrico/farmacologia , Embalagem de Alimentos/instrumentação , Conservação de Alimentos/métodos , Conservação de Alimentos/instrumentação , Antibacterianos/farmacologia , Antibacterianos/química , Reagentes de Ligações Cruzadas/química , Resistência à Tração
4.
Carbohydr Res ; 542: 109194, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38897018

RESUMO

N-(sodium 2-hydroxypropylsulfonate) chitosan (HSCS), N-sulfonate chitosan (SCS) and N-isonicotinic sulfonate chitosan (ISCS) were prepared. The structures of the prepared chitosan derivatives were characterized by nuclear magnetic resonance (1H NMR) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible (UV-vis) spectroscopy and elemental analysis (EA). Antibacterial and antibiofilm activities of these chitosan derivatives were evaluated in vitro. The minimum inhibitory concentration (MIC) of HSCS and SCS against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were 0.625 mg/mL and 0.156 mg/mL, respectively. ISCS exhibited MIC values of 0.313 mg/mL and 0.078 mg/mL against E. coli and S. aureus, respectively. ISCS demonstrated superior antibacterial and antibiofilm properties compared to SCS and HSCS. These findings suggest that the incorporation of a pyridine structure into sulfonate chitosan enhances its antibacterial and antibiofilm activities, and the prepared ISCS has a promising application prospect for controlling the reproduction of microorganisms in the field of food packaging.

5.
Hum Gene Ther ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38767504

RESUMO

Early diagnosis and intervention are pivotal in reducing colorectal cancer (CRC) incidence and enhancing patient outcomes. In this study, we focused on three genes, AQP8, GUCA2B, and SPIB, which exhibit high coexpression and play crucial roles in suppressing early-stage CRC. Our objective was to identify key miRNAs that can mitigate CRC tumorigenesis and modulate the coexpression network involving these genes. We conducted a comprehensive analysis using large-scale tissue mRNA data from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus to validate the coexpression of AQP8, GUCA2B, and SPIB, and to assess their diagnostic and prognostic significance in CRC. The mRNA-miRNA interactions were examined using MiRNet and the Encyclopedia of RNA Interactomes. Furthermore, using various molecular techniques, we conducted miRNA inhibitor transfection experiments in HCT116 cells to evaluate their effects on cell growth, migration, and gene/protein expression. Our findings revealed that, compared with normal tissues, AQP8, GUCA2B, and SPIB exhibited high coexpression and were downregulated in CRC, particularly during tumorigenesis. OncoMirs, hsa-miR-182-5p, and hsa-miR-27a-3p, were predicted to regulate these genes. MiRNA inhibition experiments in HCT116 cells demonstrated the inhibitory effects of miR-27a-3p and miR-182-5p on GUCA2B mRNA and protein expression. These miRNAs promoted the proliferation of CRC cells, possibly through their involvement in the GUCA2B-GUCY2C axis, which is known to promote tumor growth. While the expressions of AQP8 and SPIB were barely detectable, their regulatory relationship with hsa-miR-182-5p remained inconclusive. Our study confirms that hsa-miR-27a-3p and hsa-miR-182-5p are oncomiRs in CRC. These miRNAs may contribute to GUCY2C dysregulation by downregulating GUCA2B, which encodes uroguanylin. Consequently, hsa-miR-182-5p and hsa-miR-27a-3p show promise as potential targets for early intervention and treatment in the early stages of CRC.

6.
PLoS One ; 19(4): e0302275, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38626177

RESUMO

Although deep-learning methods can achieve human-level performance in boundary detection, their improvements mostly rely on larger models and specific datasets, leading to significant computational power consumption. As a fundamental low-level vision task, a single model with fewer parameters to achieve cross-dataset boundary detection merits further investigation. In this study, a lightweight universal boundary detection method was developed based on convolution and a transformer. The network is called a "transformer with difference convolutional network" (TDCN), which implies the introduction of a difference convolutional network rather than a pure transformer. The TDCN structure consists of three parts: convolution, transformer, and head function. First, a convolution network fused with edge operators is used to extract multiscale difference features. These pixel difference features are then fed to the hierarchical transformer as tokens. Considering the intrinsic characteristics of the boundary detection task, a new boundary-aware self-attention structure was designed in the transformer to provide inductive bias. By incorporating the proposed attention loss function, it introduces the direction of the boundary as strongly supervised information to improve the detection ability of the model. Finally, several head functions with multiscale feature inputs were trained using a bidirectional additive strategy. In the experiments, the proposed method achieved competitive performance on multiple public datasets with fewer model parameters. A single model was obtained to realize universal prediction even for different datasets without retraining, demonstrating the effectiveness of the method. The code is available at https://github.com/neulmc/TDCN.


Assuntos
Conscientização , Baixa Visão , Humanos , Fontes de Energia Elétrica , Gestão da Informação , Menopausa
7.
RSC Adv ; 14(12): 8161-8166, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38469187

RESUMO

CB[8]-based supramolecular assembly, i.e., 2CB[8]·[ZnCl4]·4H2O (1) (CB[8] = cucurbit[8]uril), was synthesized under solvothermal condition in the presence of [ZnCl4]2- anions as a structure inducer. 1 was applied as a high-efficiency absorbent to remove the commonly used dye amaranth (AMR) and an antibacterial drug of broad-spectrum sulfadiazine sodium (SFZ) from the aqueous solution. It showed an excellent removal rate and could remove 96.08% and 96.21% for AMR and SMZ, respectively. The adsorption behaviors were investigated using FT-IR. The differences in IR spectra revealed that the formation of inclusion complexes is the main driving force of adsorption. The phenyl and sulfonyl or sulfone moieties of AMR and SFZ entered the cavity of CB[8] in 1, and the adsorption mechanism could be due to the formation of inclusion complexes of AMR and SFZ in the CB[8] cavities of 1. This work illustrates the application prospects of CB[8]-based supramolecular assembly in environmental protection.

8.
Carbohydr Res ; 538: 109078, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38513462

RESUMO

N-(4-N'-pyridine-benzylcarbonyl chloride) chitosan (CBPyC), N-p-biguanidine benzoyl chitosan (CSBG), and N-(p-biguanidine -1-pyridine-4-benzylcarbonyl chloride) chitosan (CSQPG) were synthesized. The structures of prepared chitosan derivatives were characterized using nuclear magnetic resonance spectroscopy (NMR) and ultraviolet-visible (UV-vis) spectroscopy, and the degree of substitution was determined through elemental analysis (EA) and evaluated on the basis of the integral values in 1H NMR. The antibacterial activities of chitosan derivatives against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were investigated in vitro using antibacterial rate, minimal inhibitory concentration and minimum bacterial concentration assays. The antibiofilm activity was also assessed using the crystal violet assay. CSQPC exhibited higher antibacterial and antibiofilm activities against E. coli and S. aureus compared to CBPyC and CSBG. The antibacterial rate of CSQPG against E. coli and S. aureus at a concentration of 0.5 mg/mL was 43.3% and 100%, respectively. The biofilm inhibition rate of CSQPG at 0.5 MIC against E. coli and S. aureus was 56.5% and 69.1%, respectively. At a concentration of 2.5 mg/mL, the biofilm removal rates of E. coli and S. aureus were 72.9% and 90.1%, respectively. The antibacterial and antibiofilm activities of CSQPG were better than CSBG and CBPyC, and the combination of guanidine and quaternary ammonium further improved the positive charge density of chitosan and enhanced its antibacterial activity.


Assuntos
Quitosana , Quitosana/farmacologia , Quitosana/química , Sais , Staphylococcus aureus , Escherichia coli , Cloretos , Biofilmes , Compostos de Amônio Quaternário/farmacologia , Compostos de Amônio Quaternário/química , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana , Piridinas
9.
PLoS One ; 19(1): e0296517, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38206935

RESUMO

Key to regional sustainable development are the development and interplay of population dynamics and social welfare, each playing a significant role. As a representative region with demographic characteristics such as negative population growth and large labor outflow, the development and interaction between population and social welfare in Nanchong deserve in-depth exploration. This article takes the development of population and social welfare in Nanchong as the research object, and constructs an evaluation indicator system of population and social welfare through research backtracking, and uses entropy method and coupling coordination model to measure the development level and interactive effect of population and social welfare in Nanchong from 2010 to 2021. The research results show that: Firstly, the comprehensive evaluation results of population in Nanchong shows a linear upward trend, which indicates the stable positive effect of population structure and distribution, the gradual improvement effect of population quality effectively compensate for the weakening effect of population quantity, thus achieving the positive development of population. Secondly, the comprehensive evaluation results of social welfare in Nanchong shows an exponential upward trend, which indicates the social welfare has maintained a rapid growth momentum in various dimensions and the long-term positive effects have completely absorbed the negative effects, thus achieving the positive development of social welfare. Thirdly, during the sample period, the population and social welfare in Nanchong consistently maintained a high level of interaction strength, with factors diffusing and integrating. On this basis, the diffusion theory is used as an empirical reference to construct three interactive mechanisms between the population and social welfare in Nanchong and the implications are inferred from the empirical results.


Assuntos
Crescimento Demográfico , Seguridade Social , Dinâmica Populacional , China
10.
J Fungi (Basel) ; 10(1)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38276033

RESUMO

Lipid droplets (LDs) are intracellular organelles that play important roles in cellular lipid metabolism; they change their sizes and numbers in response to both intracellular and extracellular signals. Changes in LD size reflect lipid synthesis and degradation and affect many cellular activities, including energy supply and membrane synthesis. Here, we focused on the function of the endoplasmic reticulum-plasma membrane tethering protein Ice2 in LD dynamics in the fungal pathogen Candida albicans (C. albicans). Nile red staining and size quantification showed that the LD size increased in the ice2Δ/Δ mutant, indicating the critical role of Ice2 in the regulation of LD dynamics. A lipid content analysis further demonstrated that the mutant had lower phosphatidylcholine levels. As revealed with GFP labeling and fluorescence microscopy, the methyltransferase Cho2, which is involved in phosphatidylcholine synthesis, had poorer localization in the plasma membrane in the mutant than in the wild-type strain. Interestingly, the addition of the phosphatidylcholine precursor choline led to the recovery of normal-sized LDs in the mutant. These results indicated that Ice2 regulates LD size by controlling intracellular phosphatidylcholine levels and that endoplasmic reticulum-plasma membrane tethering proteins play a role in lipid metabolism regulation in C. albicans. This study provides significant findings for further investigation of the lipid metabolism in fungi.

11.
Microbiol Res ; 279: 127552, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38000336

RESUMO

Histone proteins are important components of nucleosomes, which play an important role in regulating the accessibility of DNA and the function of genomes. However, the effect of histone proteins dosages on physiological processes is not clear in the human fungal pathogen Candida albicans. In this study, we found that the deletion of the histone protein H3 coding gene HHT21 and the histone protein H4 coding gene HHF1 resulted in a significant decrease in the expression dosage of the histone proteins H3 and H4, which had a significant impact on the localization of the histone protein H2A and plasmid maintenance. Stress sensitivity experiments showed that the mutants hht21Δ/Δ, hhf1Δ/Δ and hht21Δ/Δhhf1Δ/Δ were more sensitive to cell wall stress induced by Calcofluor White (CFW) than the wild-type strain. Further studies showed that the decrease in the dosage of the histone proteins H3 and H4 led to the change of cell wall components, increased chitin contents, and down-regulated expression of the SAP9, KAR2, and CRH11 genes involved in the cell wall integrity (CWI) pathway. Overexpression of SAP9 could rescue the sensitivity of the mutants to CFW. Moreover, the decrease in the histone protein s dosages affected the FAD-catalyzed oxidation of Ero1 protein, resulting in the obstruction of protein folding in the ER, and thus reduced resistance to CFW. It was also found that CFW induced a large amount of ROS accumulation in the mutants, and the addition of ROS scavengers could restore the growth of the mutants under CFW treatment. In addition, the reduction of the histone proteins dosages greatly weakened systemic infection and kidney fungal burden in mice, and hyphal development was significantly impaired in the mutants under macrophage treatment, indicating that the histone proteins dosages is very important for the virulence of C. albicans. This study revealed that histone proteins dosages play a key role in the cell wall stress response and pathogenicity in C. albicans.


Assuntos
Candida albicans , Proteínas Fúngicas , Humanos , Animais , Camundongos , Proteínas Fúngicas/metabolismo , Virulência , Histonas/genética , Histonas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Parede Celular/metabolismo
12.
J Fungi (Basel) ; 9(12)2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38132782

RESUMO

DNA damage activates the DNA damage response and autophagy in C. albicans; however, the relationship between the DNA damage response and DNA damage-induced autophagy in C. albicans remains unclear. Mec1-Rad53 signaling is a critical pathway in the DNA damage response, but its role in DNA damage-induced autophagy and pathogenicity in C. albicans remains to be further explored. In this study, we compared the function of autophagy-related (Atg) proteins in DNA damage-induced autophagy and traditional macroautophagy and explored the role of Mec1-Rad53 signaling in regulating DNA damage-induced autophagy and pathogenicity. We found that core Atg proteins are required for these two types of autophagy, while the function of Atg17 is slightly different. Our results showed that Mec1-Rad53 signaling specifically regulates DNA damage-induced autophagy but has no effect on macroautophagy. The recruitment of Atg1 and Atg13 to phagophore assembly sites (PAS) was significantly inhibited in the mec1Δ/Δ and rad53Δ/Δ strains. The formation of autophagic bodies was obviously affected in the mec1Δ/Δ and rad53Δ/Δ strains. We found that DNA damage does not induce mitophagy and ER autophagy. We also identified two regulators of DNA damage-induced autophagy, Psp2 and Dcp2, which regulate DNA damage-induced autophagy by affecting the protein levels of Atg1, Atg13, Mec1, and Rad53. The deletion of Mec1 or Rad53 significantly reduces the ability of C. albicans to systematically infect mice and colonize the kidneys, and it makes C. albicans more susceptible to being killed by macrophages.

13.
J Mater Chem B ; 11(43): 10446-10454, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37888956

RESUMO

Increased antibiotic resistance has made bacterial infections a global concern, which requires novel non-antibiotic-dependent antibacterial strategies to address the menace. Antimicrobial peptides (AMPs) are a promising antibiotic alternative, whose antibacterial mechanism is mainly to destroy the membrane of bacteria. Gallium ions exhibit an antibacterial effect by interfering with the iron metabolism of bacteria. With the rapid development of nanotechnology, it is worth studying the potential of gallium-AMP-based nanocomposites for treating bacterial infections. Herein, novel gallium-based metal-organic frameworks (MOFs) were synthesized at room temperature, followed by in situ loading of the model AMP melittin. The obtained nanocomposites exhibited stronger antibacterial activity than pure MEL and gallium ions, achieving the effects of "one plus one is greater than two". Moreover, the nanocomposites showed favorable biocompatibility and accelerated healing of a wound infected by methicillin-resistant Staphylococcus aureus by down-regulation of inflammatory cytokines IL-6 and TNF-α. This work presents an innovative antibacterial strategy to overcome the antibiotic resistance crisis and expand the application of AMPs.


Assuntos
Infecções Bacterianas , Gálio , Estruturas Metalorgânicas , Staphylococcus aureus Resistente à Meticilina , Humanos , Estruturas Metalorgânicas/farmacologia , Gálio/farmacologia , Peptídeos Antimicrobianos , Antibacterianos/farmacologia , Bactérias , Íons/farmacologia
14.
Vaccines (Basel) ; 11(10)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37896925

RESUMO

The development of efficient fungal vaccines is urgent for preventing life-threatening systemic fungal infections. In this study, we prepared a synthetic, cell-based fungal vaccine for preventing systemic fungal infections using synthetic biology techniques. The synthetic cell EmEAP1 was constructed by transforming the Escherichia coli chassis using a de novo synthetic fragment encoding the protein mChEap1 that was composed of the E. coli OmpA peptide, the fluorescence protein mCherry, the Candida albicans adhesin Eap1, and the C-terminally transmembrane region. The EmEAP1 cells highly exposed the mChEap1 on the cell surface under IPTG induction. The fungal vaccine was then prepared by mixing the EmEAP1 cells with aluminum hydroxide gel and CpG. Fluorescence quantification revealed that the fungal vaccine was stable even after 112 days of storage. After immunization in mice, the vaccine resided in the lymph nodes, inducing the recruitment of CD11c+ dendritic cells. Moreover, the vaccine strongly activated the CD4+ T splenocytes and elicited high levels of anti-Eap1 IgG. By the prime-boost immunization, the vaccine prolonged the survival time of the mice infected by the C. albicans cells and attenuated fungal colonization together with inflammation in the kidneys. This study sheds light on the development of synthetic biology-based fungal vaccines for the prevention of life-threatening fungal infections.

15.
Radiother Oncol ; 189: 109937, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37797658

RESUMO

BACKGROUND AND PURPOSE: Pulmonary lymphoepithelioma-like carcinoma (PLELC) is a rare form of non-small cell lung carcinoma (NSCLC) that shares similarities with nasopharyngeal carcinoma. The optimal treatment for stage III-N2 PLELC remains controversial. METHODS AND MATERIALS: We conducted a retrospective analysis from stage III-N2 PLELC patients between 2009 and 2022 in our center. The patients were categorized into three groups: Group 1 (G1, definitive chemoradiotherapy), Group 2 (G2, radical surgery plus adjuvant chemoradiotherapy), and Group 3 (G3, radical surgery plus adjuvant chemotherapy). RESULTS: A total of 103 patients were included in the study, with 34, 25, and 44 patients in G1, G2, and G3, respectively. The median follow-up time was 47.4 months. The overall median PFS was 66.6 months, with 3-year PFS and 3-year OS rates of 66.0% and 92.4%, respectively, for all patients. Multivariate analysis revealed no significant difference in PFS between G1 and G2 (p = 0.354), while both groups exhibited significantly longer PFS than G3 (p < 0.001; p = 0.039). Similarly, no significant difference in OS was observed between G1 and G2 (p = 0.649), but both tended to demonstrate improved OS compared to G3 (p = 0.081; p = 0.092). Only one case of grade 3 radiation esophagitis was observed in G1, and no grade 3 or higher radiation pneumonitis were reported. CONCLUSIONS: Patients with stage III-N2 PLELC have a favorable prognosis, with radiotherapy playing a crucial role in treatment. Both definitive chemoradiotherapy and radical surgery followed by chemoradiotherapy demonstrate favorable efficacy and manageable toxicity.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Pulmonares , Neoplasias Nasofaríngeas , Humanos , Neoplasias Pulmonares/patologia , Estudos Retrospectivos , Estadiamento de Neoplasias , Carcinoma de Células Escamosas/patologia , Quimiorradioterapia , Neoplasias Nasofaríngeas/patologia
16.
Int J Mol Sci ; 24(18)2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37762528

RESUMO

Potassium-solubilizing bacteria are an important microbial group that play a critical role in releasing mineral potassium from potassium-containing minerals, e.g., potassium feldspar. Their application may reduce eutrophication caused by overused potassium fertilizers and facilitate plants to utilize environmental potassium. In this study, a high-efficiency potassium-solubilizing bacterium, named NK851, was isolated from the Astragalus sinicus rhizosphere soil. This bacterium can grow in the medium with potassium feldspar as the sole potassium source, releasing 157 mg/L and 222 mg/L potassium after 3 days and 5 days of incubation, respectively. 16S rDNA sequencing and cluster analysis showed that this strain belongs to Priestia megaterium. Genome sequencing further revealed that this strain has a genome length of 5,305,142 bp, encoding 5473 genes. Among them, abundant genes are related to potassium decomposition and utilization, e.g., the genes involved in adherence to mineral potassium, potassium release, and intracellular trafficking. Moreover, the strong potassium-releasing capacity of NK851 is not attributed to the acidic pH but is attributed to the extracellular potassium feldspar-binding proteins, such as the elongation factor TU and the enolase that contains potassium feldspar-binding cavities. This study provides new information for exploration of the bacterium-mediated potassium solubilization mechanisms.


Assuntos
Astrágalo , Bacillus megaterium , Potássio , Silicatos de Alumínio , Compostos de Potássio
17.
Int J Biol Macromol ; 242(Pt 2): 124877, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37182629

RESUMO

N-(4-N', N', N'-trimethylphosphonium chloride) benzoyl chitosan (TMPCS), N-(4-N', N', N'-triphenylphosphonium chloride) benzoyl chitosan (TPPCS), and N-(4-N', N', N'-trimethylmethanaminium chloride) benzoyl chitosan (TMACS) were synthesized. The structures of the products were characterized by Fourier transform infrared spectroscopy, Nuclear magnetic resonance spectroscopy and ultraviolet-visible spectroscopy. Their antibacterial activities against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were investigated in vitro using the antibacterial rate, minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), the antibiofilm activity was investigated by crystal violet assay. The antibacterial assessment revealed that the chitosan quaternary phosphonium salts of similar structure had superior antibacterial activity than chitosan quaternary ammonium salt. The antibacterial rate of CS, TMPCS, TPPCS and TMACS against E. coli at 0.5 mg/mL was 10.4 %, 42.0 %, 58.5 % and 21.6 % respectively. At the same concentration, the antibacterial rate of TMPCS, TPPCS and TMACS against S.aureus was all up to 100 %. The biofilm inhibition rate of CS, TMPCS, TPPCS and TMACS at a half of MIC against E.coli was 28.4 %, 33.9 %, 56.6 % and 57.6 % respectively, and against S.aureus was 30.8 %, 53.8 %, 62.2 % and 58.5 % respectively. The biofilm removal rate of CS, TMPCS, TPPCS, TMACS against E.coli at 2.5 mg/mL was 20.6 %, 46.4 %, 48.9 % and 41.6 % respectively, and against S.aureus at 2.5 mg/mL was 41.5 %, 60.4 %, 69.9 % and 59.01 % respectively.


Assuntos
Quitosana , Quitosana/farmacologia , Quitosana/química , Escherichia coli , Staphylococcus aureus , Cloretos , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana , Cloreto de Sódio/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Compostos de Amônio Quaternário/farmacologia , Compostos de Amônio Quaternário/química , Espectroscopia de Infravermelho com Transformada de Fourier , Biofilmes
18.
Thorac Cancer ; 14(14): 1223-1238, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36944484

RESUMO

BACKGROUND: Zinc finger protein 687 (ZNF687) has previously been discovered as a potential oncogene in individuals with giant cell tumors of the bone, acute myeloid leukemia, and hepatocellular carcinoma. However, its role and mechanism in lung adenocarcinoma (LUAD) remain unclear. METHODS: In LUAD cells, tumor, and matched adjacent tissue specimens, quantitative real-time RT- polymerase chain reaction (qRT-PCR), western blotting analyses, and immunohistochemistry staining (IHC) were conducted. Cell counting kit-8 (CCK8) assay, clonogenicity analysis, flow cytometry, and transwell assays were utilized to detect ZNF687 overexpression and knockdown impacts on cell growth, colony formation, cell cycle, migration, and invasion. Bioinformatic studies, qRT-PCR and western blotting studies were employed to validate the underlying mechanisms and signaling pathways implicated in the oncogenic effect of ZNF687. RESULTS: This study demonstrated that ZNF687 expression was elevated in LUAD cells and tissues. Individuals with upregulated ZNF687 had a poorer prognosis than those with downregulatedZNF687 (p < 0.001). ZNF687 overexpression enhanced LUAD growth, migration, invasion and colony formation, and the cell cycle G1-S transition; additionally, it promoted the epithelial-mesenchymal transition (EMT). In contrast, knocking down ZNF687 showed to have the opposite impact. Moreover, these effects were associated with the activity of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling mechanism. CONCLUSION: ZNF687 was upregulated in LUAD, and high ZNF687 expression levels are associated with poor prognoses. The activation of the PI3K/AKT signaling pathway by upregulated ZNF687 increased the proliferation of LUAD cells and tumor progression. ZNF687 may be a beneficial predictive marker and a therapeutic target in LUAD.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias Pulmonares/patologia , Linhagem Celular Tumoral , Movimento Celular , Adenocarcinoma de Pulmão/patologia , Transdução de Sinais , Proliferação de Células , Regulação Neoplásica da Expressão Gênica
19.
Sensors (Basel) ; 23(1)2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36617090

RESUMO

With the advent of the era of big data information, artificial intelligence (AI) methods have become extremely promising and attractive. It has become extremely important to extract useful signals by decomposing various mixed signals through blind source separation (BSS). BSS has been proven to have prominent applications in multichannel audio processing. For multichannel speech signals, independent component analysis (ICA) requires a certain statistical independence of source signals and other conditions to allow blind separation. independent vector analysis (IVA) is an extension of ICA for the simultaneous separation of multiple parallel mixed signals. IVA solves the problem of arrangement ambiguity caused by independent component analysis by exploiting the dependencies between source signal components and plays a crucial role in dealing with the problem of convolutional blind signal separation. So far, many researchers have made great contributions to the improvement of this algorithm by adopting different methods to optimize the update rules of the algorithm, accelerate the convergence speed of the algorithm, enhance the separation performance of the algorithm, and adapt to different application scenarios. This meaningful and attractive research work prompted us to conduct a comprehensive survey of this field. This paper briefly reviews the basic principles of the BSS problem, ICA, and IVA and focuses on the existing IVA-based optimization update rule techniques. Additionally, the experimental results show that the AuxIVA-IPA method has the best performance in the deterministic environment, followed by AuxIVA-IP2, and the OverIVA-IP2 has the best performance in the overdetermined environment. The performance of the IVA-NG method is not very optimistic in all environments.


Assuntos
Inteligência Artificial , Processamento de Sinais Assistido por Computador , Algoritmos
20.
Water Res ; 231: 119487, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36680826

RESUMO

Serious foaming problems and the excessive consumption of defoamer have undoubtedly become one of the most critical problems that hinder municipal solid waste (MSW) leachate treatment efficiency and industry development. Since there is limited research penetrating the foaming mechanism and identification of the key surfactants, current defoaming and surfactant removal techniques lack pertinence and orientation. In this study, a foaming characterization device was developed and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC/MS/MS) was optimized to accurately identify the key surfactants affecting leachate foaming and offer a glimpse into their interaction mechanisms. This study collected leachate samples from 9 typical landfills and waste-to-energy facilities of various waste compositions, climatic conditions, ages, and geographical locations. The foaming problem of leachate was mainly centered on raw leachate and nanofiltration membrane concentrate (NFC). Fresh leachate performed with relatively low foaming capacity and foam stability, associated with low surfactant concentration. The pH value of the system was positively correlated with the concentration of anionic surfactants, indicating significant impacts on surfactant release in MSW. Since the distribution characteristics of linear alkylbenzene sulfonate (LAS) in leachate were consistent with the variety of foaming performances, LAS proved to be an indispensable surfactant in the leachate involved in this study, and its content proportion escalated to 92.87% in aged leachate.


Assuntos
Eliminação de Resíduos , Poluentes Químicos da Água , Resíduos Sólidos/análise , Tensoativos , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise , Instalações de Eliminação de Resíduos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...