RESUMO
In underwater wireless optical communication, orbital angular momentum (OAM) states suffer from turbulence distortions. This study aims to investigate the effectiveness of auto-focusing and OAM entanglement of the beams in reducing the turbulence effects. We implement the single-phase approximation and the extended Huygens-Fresnel principle to derive the detection probability of the entangled Airy beams under unstable oceanic turbulence. The results show that auto-focusing can protect the signal OAM mode and suppress modal crosstalks, while entangled OAM states can further enhance the resistance against oceanic turbulence around the focus position. The numerical analysis demonstrates that after the auto-focusing position, the beams evolve in completely opposite directions, indicating that the focal length should be modulated according to the length of a practical link to enhance received signals. These findings suggest that entangled auto-focusing vortex beams may be a desirable light source in underwater communication systems.
RESUMO
Compared to horizontal transmission, the oceanic dissipation rate and temperature-salinity distribution ratio are no longer constant but vary with depth, imposing greater complexity on oceanic turbulence when beams propagate through a slant path and resulting in more limitations on the performance of underwater wireless optical communication (UWOC) links. This study focuses on investigating the performance, especially the auto-focusing characteristic, of auto-focusing hypergeometric Gaussian (AHGG) beams propagating along slant paths in oceanic turbulence. We theoretically derive the spatial coherence radius and the relative probability of the orbital angular momentum (OAM) mode for AHGG beams passing through such links. Numerical simulations reveal that AHGG beams exhibit superior propagation performance compared to hypergeometric Gaussian beams. Lower beam orders and OAM numbers contribute to improved performance, while careful selection of auto-focusing length can tangibly enhance detection performance as well. Additionally, tidal velocities and wind speeds have nonnegligible effects on OAM signal probability. Our results further demonstrate that surface buoyancy flux, temperature gradients, and waterside friction velocity significantly affect beam transmission under varying wind conditions. These findings, particularly controlling the auto-focusing length of AHGG beams to match the transmission distance, provide valuable insights for enhancing the quality of UWOC links.
RESUMO
Single-atom catalysts have emerged as cutting-edge hotspots in the field of material science owing to their excellent catalytic performance brought about by well-defined metal single-atom sites (M SASs). However, huge challenges still lie in achieving the rational design and precise synthesis of M SASs. Herein, we report a novel synthesis strategy based on the hetero-charge coupling effect (HCCE) to prepare M SASs loaded on N and S co-doped porous carbon (M1/NSC). The proposed strategy was widely applied to prepare 17 types of M1/NSC composed of single or multi-metal with the integrated regulation of the coordination environment and electronic structure, exhibiting good universality and flexible adjustability. Furthermore, this strategy provided a low-cost method of efficiently synthesizing M1/NSC with high yields, that can produce more than 50â g catalyst at one time, which is key to large-scale production. Among various as-prepared unary M1/NSC (M can be Fe, Co, Ni, V, Cr, Mn, Mo, Pd, W, Re, Ir, Pt, or Bi) catalysts, Fe1/NSC delivered excellent performance for electrocatalytic nitrate reduction to NH3 with high NH3 Faradaic efficiency of 86.6 % and high NH3 yield rate of 1.50â mg h-1 mgcat. -1 at -0.6â V vs. RHE. Even using Fe1/NSC as a cathode in a Zn-nitrate battery, it exhibited a high open circuit voltage of 1.756â V and high energy density of 4.42â mW cm-2 with good cycling stability.
RESUMO
Cirrhosis is a persistent hepatic ailment that emerges from a range of causes, including viral infections, alcoholic liver disease, and non-alcoholic fatty liver disease. It is distinguished by the replacement of normal liver parenchyma with fibrous scar tissue, culminating in the development of hepatic insufficiency, portal hypertension, and eventual liver collapse. Several molecular and cellular mechanisms contribute to cirrhosis' pathogenesis, including activation of immune cells and dysregulation of immune-related pathways. Weighted Gene Co-expression Network Analysis (WGCNA) is a powerful data mining application used to identify gene modules and hub genes that are closely associated with specific phenotypes or conditions of interest. In this study, we performed WGCNA on publicly available gene expression datasets and subsequently assessed the roles of immune-related genes in the etiology and progression of cirrhosis, intending to explore potential therapeutic targets for this disease. GSE36411 gene expression profiling was extracted from the Gene Expression Omnibus repository (GEO). The transcriptomic data were submitted to Weighted Gene Co-expression Network Analysis (WGCNA) to screen for the presence of key genes, and immune-related genes were filtered by comparison to the InateDB database. Cancer Genome Atlas (TCGA) was included in the study to validate the significant modules generated from WGCNA. The key gene interaction network was constructed using GeneMANIA and Metascape. Kaplan-Meier method and Spearman correlation were used to evaluate the correlation of immune-related genes with prognosis, tumor microenvironment, and immune cell infiltration. Finally, we explored a possible mechanism using gene set enrichment (GSEA) analyses. In total, 2,102 differentially expressed genes (DEGs) were identified from the gene expression profile dataset. A weighted gene co-expression network analysis was performed, resulting in the classification of genes into 3 modules. Among these modules, the turquoise module was found to be most closely associated with cirrhosis. By comparing the turquoise module genes with an InateDB immune-related gene set, we identified 157 immune-associated genes. In addition, our study found that many hub genes are strongly associated with the number of immune-related genes in liver cirrhosis, in addition to a few modules associated with immune infiltration. It turns out that these hub genes were engaged in migration, activation, and immune cell regulation, as well as in the signaling pathways that drive the immune response to infection. Our research offered a deeper understanding of the underlying processes of immune infiltration in cirrhosis and also suggested potential treatment options for this troublesome condition. Our results demonstrate the effectiveness of WGCNA in uncovering new knowledge regarding the biology of cirrhosis and the function of the immune system in this disease. More studies ought to focus on the validation of the identified hub genes and the determination of their clinical relevance. These results could serve as the basis for the creation of more potent therapies for those with liver cancer linked to cirrhosis.
Assuntos
Perfilação da Expressão Gênica , Cirrose Hepática , Humanos , Cirrose Hepática/genética , Transcriptoma , Relevância ClínicaRESUMO
A colorimetric detection method for Escherichia coli (E. coli) in water was established based on a T7 phage tail fiber protein-magnetic separation. Firstly, the tail fiber protein (TFP) was expressed and purified to specifically recognize E. coli, which was verified by using fusion protein GFP-tagged TFP (GFP-TFP) and fluorescence microscopy. Then TFP conjugated with magnetic beads were applied to capture and separate E. coli. The TFP was covalently immobilized on the surface of magnetic beads and captured E. coli as verified by scanning electron microscopy (SEM). Finally, polymyxin B was used to lyse E. coli in solution and the released intracellular ß-galactosidase (ß-gal) could hydrolyze the colorimetric substrate chlorophenol red-ß-D-galactopyranoside (CPRG), causing color change from yellow to purple. The high capture efficiencies of E. coli ranged from 88.70% to 95.65% and E. coli could be detected at a concentration of 102 CFU/mL by naked eyes. The specificity of the chromogenic substrate was evaluated using five different pathogen strains as competitors and tests with four kinds of real water samples showed recoveries of 86.00% to 92.25%. The colorimetric changes determined by visual inspection can be developed as an efficient platform for point-of-care detection of E. coli in resource-limited regions.
Assuntos
Bacteriófagos , Escherichia coli , Escherichia coli/química , Colorimetria/métodos , Separação Imunomagnética/métodos , ÁguaRESUMO
A pair of composite probes based on aptamer modified polyhedral oligomeric silsesquioxane-perovskite quantum dots (POSS-PQDs-Apt) as signal probe and titanium carbide (Ti3C2) MXenes as quencher were prepared for the first time. They were employed to fabricate one turn-on-type aptasensor relying on fluorescence resonance energy transfer (FRET) for Vibrio parahaemolyticus (VP) determination. The POSS-PQDs-Apt can be adsorbed on the MXenes nanosheets, and its fluorescence was quenched due to the FRET. After the composite probes were incubated with VP for 50 min, the POSS-PQDs-Apt binding with VP can be released from the surface of MXenes, and the signal recovered due to its higher affinity to the VP than MXenes. The fluorescence intensity from 519 nm emission of the system was measured at 480 nm excitation. Under In optimized conditions, the assay can determine VP in the concentration range 102 - 106 cfu/mL, and the detection limit (LOD) was 30 cfu/mL using fluorescence detection. The LOD is still 100 cfu/mL by naked eye detection which is proper for on-line monitoring VP in aquaculture water. This method was also used to detect VP in actual samples of seawater, the recovery of spiked samples was between 93% and 106%, and relative standard deviation (RSD) was between 2.7% and 6.7%. The result is consistent with the plate count. Therefore, this assay could provide a candidate platform for screening VP in aquaculture industry.
Assuntos
Aptâmeros de Nucleotídeos/química , Compostos de Organossilício/química , Pontos Quânticos/química , Titânio/química , Vibrio parahaemolyticus/isolamento & purificação , Poluentes da Água/análise , Carga Bacteriana/métodos , Técnicas Biossensoriais/métodos , Compostos de Cálcio/química , Transferência Ressonante de Energia de Fluorescência , Limite de Detecção , Óxidos/química , Água do Mar/análise , Água do Mar/microbiologia , Vibrio parahaemolyticus/químicaRESUMO
The permeable brick pavement system (PBPs) is one of a widely used low impact development (LID) measures to alleviate runoff volume and pollution caused by urbanization. The performance of PBPs on decreasing runoff volume is decided by its permeability, and it was general described by hydraulic conductivity based on Darcy's law. But there is large error when using hydraulic conductivity to describe the infiltration of PBPs, and which infiltration process is not following Darcy's law, so it is important to find more accurate infiltration models to describe the infiltration of PBPs. The Horton, Philip, Green-Ampt, and Kostiakov infiltration models were selected to find an optimal model to investigate infiltration performance of PBPs via a laboratory-scale experiment, and the maximum absolute error (MAE), Bias, and coefficient of determination (R2) were selected to evaluate the models' errors via fitting with experiment data. The results showed that the fitting accuracy of Kostiakov, Philip, and Green-Ampt models was significantly affected by the monitoring area and hydraulic gradients. Meanwhile, Horton model fitted well (MAE = 0.25-0.32 cm/h, Bias = 0.07-0.11 cm/h, and R2 = 0.98-0.99) with the experiment data, and the parameters of the Horton model often can be achieved by monitoring, such as the maximum infiltration rate and the stable infiltration rate. Therefore, the Horton model is an optimal model to describe the infiltration performance of PBPs, which can also be adopted to evaluate hydrological characterization of PBPs.
Assuntos
Chuva , Movimentos da Água , Hidrologia , LaboratóriosRESUMO
The authors describe a microfluidic chip-based aptasensor platform combined with magnetic tripartite DNA structure-functionalized nanocomposites to achieve simultaneous determination of kanamycin (KANA), aflatoxin M1 (AFM1), and 17ß-estradiol (E2) in milk. The two-duplex tripartite DNA nanostructure was first assembled on the surface of magnetic beads. When the aptamer on the probes recognized the specific target, the aptamer-target would be released into the supernatant. The pre-primer@circular DNA template structure initiates rolling circle amplification (RCA) by phi29 polymerase. After magnetic separation, the magnetic nanocomposites were added into a solution containing three different lengths of complementary strands to the RCA products. The number of complementary strands significantly decrease, and this can be quantitated by the microfluidic chip. Further, the employment of magnetic nanocomposites and microfluidic chip not only resolve the complex matrix interference, but also dramatically enhances the determination selectivity and sensitivity. This aptasensor allows for determination of KANA, AFM1, and E2 with limits of detection as low as 0.32 pg mL-1, 0.95 pg mL-1, and 6.8 pg mL-1, respectively. This novel method exhibits the advantages of excellent stability and fast response time (< 3 min on microfluidic chip platform) for simultaneous determination of KANA, AFM1, and E2 in milk samples and ensures food safety. Graphical abstract.
Assuntos
Aflatoxina M1/química , Sondas de DNA/química , Estradiol/química , Canamicina/química , Microfluídica/métodos , Nanoestruturas/química , Técnicas Biossensoriais/métodos , Humanos , Fenômenos MagnéticosRESUMO
BACKGROUND: Only a paucity of large-scale perspective and cross-sectional studies on H. pylori infection in China have been published. The purpose of this study was to investigate the prevalence and risk factors for H. pylori infection among residents of Jidong community located in Hebei Province of China. METHODS: A perspective, cross-sectional study was conducted in Jidong community. Questionnaires and 13C-urea breath test were performed, and 10-ml blood samples were obtained for laboratory tests. RESULTS: Four thousand seven hundred ninety-six subjects were enrolled in this study, and 2506 (52.25%) were H. pylori positive. There was no difference in prevalence between both sexes (P = 0.5974). Age (P = 0.004) and education level (P = 0.0128) were significantly associated with H. pylori infection, and there were statistical trends in the prevalence across five age subgroups (χ2 test for trend = 23.5; P < 0.001) and education levels (χ2 test for trend = 19.50; P < 0.001). H. pylori infection was also associated with marital status (P = 0.0243), source of drinking water (P = 0.0433), frequency of eating raw garlic (P = 0.0310), alcohol drinking (P = 0.0207), knowledge about H. pylori transmission route (P = 0.0125) and related diseases (P = 0.0257). Age, alcohol drinking and knowledge about transmission route were found to be independent predictors of H. pylori infection. CONCLUSIONS: More than half of the population was infected with H. pylori in Jidong community. The socio-demographic profiles, socio-economic factors and lifestyle are worthy taking into consideration to prevent diseases associated with H. pylori infection. Understanding the prevalence and risk patterns for H. pylori infection in China will help in prioritizing public health efforts to better manage the H. pylori infection.
Assuntos
Infecções por Helicobacter , Helicobacter pylori/isolamento & purificação , Adulto , Testes Respiratórios/métodos , China/epidemiologia , Estudos Transversais , Feminino , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/epidemiologia , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores SocioeconômicosRESUMO
PURPOSE: This study aimed to explore the value of preoperative ultrasonography (US) in evaluating the peritoneal cancer index (PCI) of pseudomyxoma peritonei (PMP). METHODS: An ultrasound examination was performed on 59 patients with PMP before surgery, and the ultrasound PCI was evaluated. The accuracy of ultrasound PCI score was evaluated with the surgical PCI score as the gold standard. RESULTS: The preoperative ultrasound PCI was compared with the surgical PCI. The Spearman correlation coefficient of the total PCI score was 0.608 (P < 0.05). The difference in the Spearman correlation coefficient between the preoperative ultrasound PCI and the surgical PCI in areas 0-7 was statistically significant. (1) Among them, the total score and the correlation between 0-3 and 6 were higher. (2) Compared with the surgical PCI, overestimation (> 20%) was concentrated mainly in areas 2 and 4-8 for 2 points, and underestimation (< 20%) was concentrated mainly in areas 1, 3, 4, and 8 for 3 points. (3) The sensitivity and specificity of preoperative ultrasound for predicting the presence or absence of lesions were 85.7% and 50.0%, respectively. The sensitivity of LS 1, LS 2, and LS 3 was 31.7%, 48.2%, and 71.0%, respectively, and the specificity was 44.8%, 55.3%, and 58.8%, respectively. CONCLUSION: The ultrasound examination can be used to score the preoperative PCI, judge the severity, and predict the prognosis in patients with PMP.
Assuntos
Neoplasias Peritoneais/patologia , Cuidados Pré-Operatórios , Pseudomixoma Peritoneal/patologia , Índice de Gravidade de Doença , Ultrassonografia/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Peritoneais/diagnóstico por imagem , Neoplasias Peritoneais/cirurgia , Prognóstico , Pseudomixoma Peritoneal/diagnóstico por imagem , Pseudomixoma Peritoneal/cirurgiaRESUMO
Background and aims: The aim of this study was to compare and analyze the feasibility and safety of two methods of endoscopic full-thickness resection (EFTR) for the management of challenging epithelial and subepithelial neoplasms that are not amenable to resection techniques.Material and methods: This was a retrospective case series study of patients who underwent one of two methods of EFTR, resection using ESD knives and post-resection closure with OTSC (Group 1), or closure with OTSC and secondary EFTR with snare (Group 2).Results: Of 11 patients, six were in Group 1 and five in Group 2. The mean time of the EFTR procedure was 76.83 ± 34.97 min in Group 1 which is significantly longer than that of Group 2 (p = .0128). The mean time of OSTC closure and length of hospital stay of Group 1 were also longer compared to Group 2, but the difference was not significant. Complete resection (R0) and technical success rates of Group 1 and Group 2 were 83.3% and 100% (p = .338), respectively. VAS scores of Group 1 immediately after the operation and after 24 h are significantly higher than those of Group 2 (p = .047 and p = .009, respectively). In Group 1, one patient had delayed perforation which led to fever and pneumoperitoneum, and one patient developed abdominal pain. No complications associated with the endoscopic procedure were observed in Group 2.Conclusion: EFTR of pre-resection closure are potentially faster compared with the concept of applying closure after EFTR. Larger prospective controlled studies comparing these two techniques are warranted in the future.
Assuntos
Ressecção Endoscópica de Mucosa/normas , Endoscopia/normas , Pneumoperitônio/cirurgia , Neoplasias Gástricas/cirurgia , Instrumentos Cirúrgicos/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Resultado do TratamentoRESUMO
A mesoporous MnCo2 O4 electrode material is made for bifunctional oxygen electrocatalysis. The MnCo2 O4 exhibits both Co3 O4 -like activity for oxygen evolution reaction (OER) and Mn2 O3 -like performance for oxygen reduction reaction (ORR). The potential difference between the ORR and OER of MnCo2 O4 is as low as 0.83â V. By XANES and XPS investigation, the notable activity results from the preferred MnIV - and CoII -rich surface. The electrode material can be obtained on large-scale with the precise chemical control of the components at relatively low temperature. The surface state engineering may open a new avenue to optimize the electrocatalysis performance of electrode materials. The prominent bifunctional activity shows that MnCo2 O4 could be used in metal-air batteries and/or other energy devices.
RESUMO
Preparing nonprecious metal catalysts with high activity in the oxygen reduction reaction (ORR) can promote the development of energy conversion devices. Support-free porous Mn2 O3 was synthesized by a facile aerosol-spray-assisted approach (ASAA) and subsequent thermal treatment, and exhibited ORR activity that is comparable to commercial Pt/C The catalyst also exhibits notably higher activity than other Mn-based oxides, such as Mn3 O4 and MnO2 . The rotating ring disk electrode (RRDE) study indicates a typical 4-electron ORR pathway on Mn2 O3 . Furthermore, the porous Mn2 O3 demonstrates considerable stability and a good methanol tolerance in alkaline media. In light of the low cost and high earth abundance of Mn, the highly active Mn2 O3 is a promising candidate to be used as a cathode material in metal-air batteries and alkaline fuel cells.
RESUMO
Noble metal nanoparticles (NPs) with 1-5â nm diameter obtained from NaHB4 reduction possess high catalytic activity. However, they are rarely used directly. This work presents a facile, versatile, and efficient aerosol-spray approach to deliver noble-metal NPs into metal oxide supports, while maintaining the size of the NPs and the ability to easily adjust the loading amount. In comparison with the conventional spray approach, the size of the loaded noble-metal nanoparticles can be significantly decreased. An investigation of the 4-nitrophenol hydrogenation reaction catalyzed by these materials suggests that the NPs/oxides catalysts have high activity and good endurance. For 1 %â Au/CeO2 and Pd/Al2 O3 catalysts, the rate constants reach 2.03 and 1.46â min(-1) , which is much higher than many other reports with the same noble-metal loading scale. Besides, the thermal stability of catalysts can be significantly enhanced by modifying the supports. Therefore, this work contributes an efficient method as well as some guidance on how to produce highly active and stable supported noble-metal catalysts.
RESUMO
BACKGROUND: Zuo-Jin-Wan (ZJW), a traditional Chinese medicine formula, has been identified to be effective against drug resistance in cancer. In the present study, we investigated the effect of ZJW on acquired oxaliplatin-resistant and the PI3K/Akt/NF-κB pathway in vitro. METHODS: We tested the dose-response relationship of ZJW on reversing drug-resistance by CCK-8 assay and flow cytometry analysis in vitro. The protein expression of P-gp, MRP-2, LRP, and ABCB1 mRNA expression level were evaluated by Western blot and quantitative RT-PCR. The activities of PI3K/Akt/NF-κB pathway were also examined with or without ZJW, including Akt, IκB, p65 and their phosphorylation expression. RESULTS: We found that ZJW significantly enhanced the sensitivity of chemotherapeutic drugs and increased oxaliplatin (L-OHP)-induced cell apoptosis in a time- and dose-dependent manner. Moreover, both ZJW and a PI3K specific inhibitor (LY294002) suppressed phosphorylation of Akt (Ser473) and NF-κB, which is necessary in the activation of the PI3K/Akt/NF-κB pathway. The effect of ZJW in reversing drug-resistance and suppressing phosphorylation of Akt (Ser473) and NF-κB were weakened after treatment with a PI3K/Akt activator in HCT116/L-OHP cells. CONCLUSIONS: Our study has provided the first direct evidence that ZJW reverses drug-resistance in human colorectal cancer by blocking the PI3K/Akt/NF-κB signaling pathway, and could be considered as a useful drug for cancer therapy.
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/farmacologia , Neoplasias do Colo/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , NF-kappa B/metabolismo , Neoplasias/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/fisiopatologia , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Humanos , Proteína 2 Associada à Farmacorresistência Múltipla , Neoplasias/tratamento farmacológico , Compostos Organoplatínicos/farmacologia , Oxaliplatina , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacosRESUMO
Feature selection (FS) has recently attracted considerable attention in many fields. Highly-overlapping classes and skewed distributions of data within classes have been found in various classification tasks. Most existing FS methods are all instance-based, which ignores the significant differences in characteristics between the particular outliers and the main body of the class, causing confusion for classifiers. In this paper, we propose a novel supervised FS method, Intrusive Outliers-based Feature Selection (IOFS), to find out what kind of outliers lead to misclassification and exploit the characteristics of such outliers. In order to accurately identify the intrusive outliers (IOs), we provide a density-mean center algorithm to obtain the appropriate representative of a class. A special distance threshold is given to obtain the candidate for IOs. Combining with several metrics, mathematical formulations are provided to evaluate the overlapping degree of the intrusive class pairs. Features with high overlapping degrees are assigned to low rankings in IOFS method. An extension of IOFS based on a small number of extreme IOs, called E-IOFS, is also proposed. Three theoretical proofs are provided for the essential theoretical basis of IOFS. Experiments comparing against various state-of-the-art methods on eleven benchmark datasets show that IOFS is rational and effective, especially on the datasets with higher overlapping classes. And E-IOFS almost always outperforms IOFS.
RESUMO
The integration of recognition and therapeutic functions in multifunctional biosensors is of great importance in guaranteeing food security and reducing the occurrence of foodborne illness caused by foodborne pathogens. In this study, a biosensor utilizing a "sense-and-treat" approach was developed by integrating phage tailspike protein (TSP) with gold nanoparticles (AuNPs@TSP). The synthesized AuNPs@TSP showed strong binding affinity towards Salmonella typhimurium causing color changes and exhibited effective bactericidal activity when exposed to near-infrared (NIR) irradiation. This biosensor facilitated rapid colorimetric detection of S. typhimurium in 50 min, with a LOD (limit of detection) of 2.53 × 103 CFU/mL output on a smartphone APP after analyzing the red-green-blue (RGB) values from color rendering results. Furthermore, the biosensor displayed high selectivity, rapid response time, and broad applicability when tested with real samples. Moreover, the biosensor exhibited a remarkably efficient antibacterial efficacy of 100 % against S. typhimurium under 808 nm light irradiation for 6 min. This study provides a comprehensive investigation into the potential utilization of biosensors for rapid detection and eradication of foodborne pathogens in food industry.
Assuntos
Técnicas Biossensoriais , Ouro , Nanopartículas Metálicas , Salmonella typhimurium , Smartphone , Proteínas da Cauda Viral , Ouro/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/efeitos da radiação , Salmonella typhimurium/isolamento & purificação , Salmonella typhimurium/efeitos dos fármacos , Técnicas Biossensoriais/métodos , Proteínas da Cauda Viral/química , Antibacterianos/farmacologia , Antibacterianos/química , Limite de Detecção , Colorimetria/métodos , Raios Infravermelhos , Glicosídeo HidrolasesRESUMO
Foodborne pathogen infection poses a significant threat to public health and is considered as one of the most serious hazards in global food safety. Herein, a sensitive and efficient method for on-site monitoring of foodborne pathogens was developed by using a smartphone-assisted paper-sensor combined with phage-derived bacterial-binding proteins-nano magnetic beads (PBPs-MBs). PBPs including tail fiber protein (TFP:gp13), cell-wall binding domain (CBD) of endolysin and tailspike protein (TSP) coated on the surface of MBs were applied for rapid separation and enrichment of targeted bacteria (Escherichia coli O157:H7, Staphylococcus aureus and Salmonella typhimurium, respectively) from food samples in 20 min before detection on paper-based sensors. The paper-based sensor was loaded with the lytic agent (polymyxin B) to induce bacterial lysis and release specific endogenous enzymes. Subsequently, three distinct chromogenic substrates were hydrolyzed by their corresponding enzymes, resulting in characteristic color changes on the paper, respectively. In addition, a smartphone APP for red-green-blue (RGB) color analysis of paper was able to directly detect three foodborne pathogens. As a result, the limit of detection (LOD) values for three foodborne pathogens were found to be 2.44 × 102, 2.68 × 104 and 4.62 × 103 CFU/mL, respectively, which were much lower than other studies (106-108 CFU/mL) based on enzymes. Moreover, the feasibility of this approach was further assessed through the successful detection of targeted bacteria in real samples with satisfactory recovery rates. In conclusion, this smartphone-assisted biosensor offers promising application potential for point-of-care testing (POCT) of foodborne pathogens in resource-scarce areas.
Assuntos
Bacteriófagos , Técnicas Biossensoriais , Proteínas de Transporte , Proteínas de Bactérias , Smartphone , Salmonella typhimurium , Microbiologia de AlimentosRESUMO
Long noncoding RNAs (lncRNAs) are RNA transcripts longer than 200 nucleotides that do not code for proteins but have been linked to cancer development and metastasis. Metastasis-associated lung adenocarcinoma transcript 1 (MALAT-1) influences crucial cancer hallmarks through intricate molecular mechanisms, including proliferation, invasion, angiogenesis, apoptosis, and the epithelial-mesenchymal transition (EMT). The current article highlights the involvement of MALAT-1 in drug resistance, making it a potential target to overcome chemotherapy refractoriness. It discusses the impact of MALAT-1 on immunomodulatory molecules, such as major histocompatibility complex (MHC) proteins and PD-L1, leading to immune evasion and hindering anti-tumor immune responses. MALAT-1 also plays a significant role in cancer immunology by regulating diverse immune cell populations. In summary, MALAT-1 is a versatile cancer regulator, influencing tumorigenesis, chemoresistance, and immunotherapy responses. Understanding its precise molecular mechanisms is crucial for developing targeted therapies, and therapeutic strategies targeting MALAT-1 show promise for improving cancer treatment outcomes. However, further research is needed to fully uncover the role of MALAT-1 in cancer biology and translate these findings into clinical applications.
RESUMO
Bacillus cereus is a prevalent foodborne pathogen that induces food poisoning symptoms such as vomiting and diarrhea. Its capacity to form spores and biofilm enables it to withstand disinfectants and antimicrobials, leading to persistent contamination during food processing. Consequently, it is necessary to develop novel and efficient antimicrobial agents to control B. cereus, its spores, and biofilms. Peptidoglycan hydrolases have emerged as a promising and eco-friendly alternative owing to their specific lytic activity against pathogenic bacteria. Here, we identified and characterized a Lysozyme-like cell wall hydrolase Lys14579, from the genome of B. cereus ATCC 14579. Recombinant Lys14579 specifically lysed B. cereus without affecting other bacteria. Lys14579 exhibited strong lytic activity against B. cereus, effectively lysing B. cereus cell within 20 min at low concentration (10 µg/mL). It also inhibited the germination of B. cereus spores and prevented biofilm formation at 12.5 µg/mL. Moreover, Lys14579 displayed good antimicrobial stability with negligible hemolysis in mouse red blood cells and no cytotoxicity against RAW264.7 cells. Notably, Lys14579 effectively inhibited B. cereus in boiled rice and minced meat in a dose-dependent manner. Furthermore, bioinformatics analysis and point mutagenesis experiments revealed that Glu-47 was the catalytic site, and Asp-57, Gln-60, Ser-61 and Glu-63 were active-site residues related with the cell wall lytic activity. Taken together, Lys14579 could be a promising biocontrol agent against vegetative cells, spores, and biofilm of B. cereus in food industry.