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1.
Langmuir ; 40(21): 11106-11115, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38745419

ABSTRACT

Polycyclic aromatic hydrocarbons (PAHs), as persistent environmental pollutants, often reside in nonaqueous-phase liquids (NAPLs). Mycobacterium sp. WY10, boasting highly hydrophobic surfaces, can adsorb to the oil-water interface, stabilizing the Pickering emulsion and directly accessing PAHs for biodegradation. We investigated the impact of Triton X-100 (TX100) on this interfacial uptake of phenanthrene (PHE) by Mycobacteria, using n-tetradecane (TET) and bis-(2-ethylhexyl) phthalate (DEHP) as NAPLs. Interfacial tension, phase behavior, and emulsion stability studies, alongside confocal laser scanning microscopy and electron microscope observations, unveiled the intricate interplay. In surfactant-free systems, Mycobacteria formed stable W/O Pickering emulsions, directly degrading PHE within the NAPLs because of their intimate contact. Introducing low-dose TX100 disrupted this relationship. Preferentially binding to the cells, the surfactant drastically increased the cell hydrophobicity, triggering desorption from the interface and phase separation. Consequently, PAH degradation plummeted due to hindered NAPL access. Higher TX100 concentrations flipped the script, creating surfactant-stabilized O/W emulsions devoid of interfacial cells. Surprisingly, PAH degradation remained efficient. This paradox can be attributed to NAPL emulsification, driven by the surfactant, which enhanced mass transfer and brought the substrate closer to the cells, despite their absence at the interface. This study sheds light on the complex effect of surfactants on Mycobacteria and PAH uptake, revealing an antagonistic effect at low concentrations that ultimately leads to enhanced degradation through emulsification at higher doses. These findings offer valuable insights into optimizing bioremediation strategies in PAH-contaminated environments.


Subject(s)
Biodegradation, Environmental , Mycobacterium , Octoxynol , Phenanthrenes , Surface-Active Agents , Phenanthrenes/chemistry , Phenanthrenes/pharmacology , Phenanthrenes/metabolism , Surface-Active Agents/chemistry , Surface-Active Agents/pharmacology , Mycobacterium/metabolism , Mycobacterium/drug effects , Mycobacterium/chemistry , Octoxynol/chemistry , Emulsions/chemistry , Alkanes/chemistry , Alkanes/metabolism , Hydrophobic and Hydrophilic Interactions
2.
Appl Opt ; 63(10): A70-A77, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38568513

ABSTRACT

Tungsten oxide (W O 3) has been widely used in hydrogen sensing due to its stable chemical properties and high oxygen vacancy diffusion coefficient. However, the response of pure W O 3 to hydrogen is slow, and doping is an effective way to improve the hydrogen sensing performance of W O 3 materials. In this paper, W O 3/P t/P E G/S i O 2 porous film was prepared by the sol-gel method using tungsten powder, H 2 O 2 and C 2 H 5 O H as precursors, polyethylene glycol (PEG) as the pore-forming agent, and tetraethyl orthosilicate (TEOS) as the S i O 2 source material. The sensing properties of the W O 3 composite for hydrogen were characterized by a transmission optical fiber hydrogen sensing system made at home. The process parameters such as water bath time, aging time, W:PEG ratio, and W:TEOS ratio were optimized to improve the sensitivity and response time of the sensing film. The experimental results indicate that the sensitivity is 15.68%, the average response time is 45 s, and the repeatability is up to 98.74% in 16 consecutive tests. The linearity index R 2 is 0.9946 within the hydrogen concentration range of 5000 ppm to 50,000 ppm. The film responds only to H 2 when the concentration of interfering gases (C H 4, CO, C O 2) is 2000 ppm. The hydrogen sensing performance of the optimized film is significantly improved compared with that of the undoped film.

4.
J Ethnopharmacol ; 322: 117561, 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38072290

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Syringa Pubescens Turcz. (SP), a member of the Oleaceae family, is a species of plant known as Syringa. Flowers, as the medicinal part, are commonly used in the treatment of hepatitis and tonsillitis. AIM OF THE STUDY: The research was the first to assess the antioxidant and anti-inflammatory potential of different parts of SP flowers (SPF) in vitro. The most promising fraction was ethyl acetate fraction of SP flower (SPFEA). The antioxidant, anti-inflammatory and analgesic activities of SPFEA were further studied, and the chemical components were identified. METHODS: HPLC was used to identify the major components in various fraction of SPF. DPPH and ABTS + radical scavenging assays as well as FRAP test and ß-carotene bleaching test were employed to assess the antioxidant potential of SPF fraction in vitro. The inhibitory effect on NO production in LPS-treated RAW264.7 cells and heat-induced protein denaturation test were used to evaluate the anti-inflammatory potential of SPF fraction. Further analysis of the biological activity of SPFEA was performed. Acute toxicity test was conducted to assess the toxicity of SPFEA. The anti-inflammatory effect was assessed by utilizing xylene induced ear edema model, carrageenan-induced foot edema model and peritonitis model in vivo. The analgesic effect of SPFEA was evaluated using hot plate test, tail immersion test, formaldehyde test as well as acetic acid-induced abdominal writhing pain experiment in vivo. In carrageenan induced foot edema model, ELISA kits were employed to measure levels of inflammation factors (NO, TNF-α, IL-6, COX-2, IL-1ß) in foot tissue as well as MDA, CAT, SOD, GSH-PX levels in liver tissue. RESULTS: HPLC results showed that there were significant differences in bioactive substances among different fractions of SPF, and SPFEA was rich in bioacitve components. Compared with other fractions of SPF, SPFEA exhibited better antioxidant and anti-inflammatory abilities. The 3000 mg/kg SPFEA group in mice had no obvious side effects. The xylene-induced ear edema model, carrageenan-induced foot edema and peritonitis models demonstrated that the SPFEA had significant anti-inflammatory effect. Moreover, inflammation factors including NO, TNF-α, IL-6, COX-2, IL-1ß were significantly reduced in SPFEA groups in foot tissue induced by carrageenan. Additionally, SPFEA effectively decreased liver tissue oxidative stress levels (MDA, SOD, GSH-PX and CAT). The bioactivities of SPFEA demonstrated a clear dose-dependent relationship. The results of the hot plate test, tail immersion test, formaldehyde test and acetic acid-induced abdominal writhing pain experiments indicated the SPFEA possessed an excellent analgesic effect, and this effect was in dose-dependent manner. CONCLUSION: The study provides a scientific foundation for understanding the pharmacological action of SPFEA. It has been indicated that SPFEA has excellent antioxidant, analgesic and anti-inflammatory effects.


Subject(s)
Acetates , Peritonitis , Syringa , Mice , Animals , Antioxidants/adverse effects , Carrageenan , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Plant Extracts/chemistry , Tumor Necrosis Factor-alpha , Interleukin-6 , Cyclooxygenase 2/metabolism , Xylenes , Pain/drug therapy , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Analgesics/pharmacology , Analgesics/therapeutic use , Inflammation/chemically induced , Inflammation/drug therapy , Inflammation/metabolism , Acetic Acid/therapeutic use , Formaldehyde , Flowers/metabolism , Edema/chemically induced , Edema/drug therapy , Edema/metabolism , Peritonitis/chemically induced , Peritonitis/drug therapy , Superoxide Dismutase/metabolism
5.
Molecules ; 28(23)2023 Nov 27.
Article in English | MEDLINE | ID: mdl-38067533

ABSTRACT

The flower of Syringa pubescens Turcz. is used in Chinese folk medicine and also as a flower tea for healthcare. The effects of five drying methods on the active compound contents, the antioxidant abilities, anti-inflammatory properties and enzyme inhibitory activities were evaluated. The plant materials were treated using shade-drying, microwave-drying, sun-drying, infrared-drying and oven-drying. The seven active compounds were simultaneously determined using an HPLC method. Furthermore, the chemical profile was assessed using scanning electron microscopy, ultraviolet spectroscopy and infrared spectroscopy. The antioxidant capacities and protective effects on L02 cells induced with hydrogen peroxide were measured. The anti-inflammatory effects on lipopolysaccharide-induced RAW264.7 cells were investigated. The enzyme inhibitory activities were determined against α-amylase, α-glucosidase cholinesterases and tyrosinase. The results indicated that drying methods had significant influences on the active compound contents and biological properties. Compared with other samples, the OD samples possessed low IC50 values with 0.118 ± 0.004 mg/mL for DPPH radical, 1.538 ± 0.0972 for hydroxyl radical and 0.886 ± 0.199 mg/mL for superoxide radical, while the SHD samples had stronger reducing power compared with other samples. The SHD samples could be effective against H2O2-induced injury on L02 cells by the promoting of T-AOC, GSH-PX, SOD and CAT activities and the reducing of MDA content compared with other samples. Furthermore, SPF samples, especially the SHD sample, could evidently ameliorate inflammation through the inhibition of IL-6, IL-1ß and TNF-α expression. All the studied SPF samples exhibited evidently inhibitory effects on the four enzymes. The IC50 values of inhibitory activity on α-glucosidase and α-amylase from SHD sample were 2.516 ± 0.024 and 0.734 ± 0.034 mg/mL, respectively. SD samples had potential inhibitory effects on cholinesterases and tyrosinase with IC50 values of 3.443 ± 0.060 and 1.732 ± 0.058 mg/mL. In consideration of active compound contents and biological activities, it was recommended that SHD and SD be applied for drying SPF at an industrial scale.


Subject(s)
Antioxidants , Syringa , Antioxidants/pharmacology , Antioxidants/chemistry , Plant Extracts/pharmacology , Plant Extracts/chemistry , Monophenol Monooxygenase , alpha-Glucosidases , Hydrogen Peroxide , Anti-Inflammatory Agents/pharmacology , Flowers , alpha-Amylases , Cholinesterases
6.
J Agric Food Chem ; 71(28): 10701-10709, 2023 Jul 19.
Article in English | MEDLINE | ID: mdl-37409796

ABSTRACT

N-Acetylneuraminic acid (NeuAc) is the predominant sialic acid found in human cells and a human-identical milk monosaccharide. Due to its numerous health benefits, it has great commercial potential in the pharmaceutical, cosmetic, and food industries. Microbial synthesis via metabolic engineering strategies is an important approach to its large-scale production. In this study, a NeuAc synthetic pathway was constructed in Escherichia coli BL21(DE3) by deleting the competitive pathway genes and introducing two genes encoding UDP-N-acetylglucosamine (GlcNAc) 2-epimerase (NeuC) and NeuAc synthase (NeuB). UDP-GlcNAc pathway genes, glmS, glmM, and glmU, were overexpressed to strengthen precursor supply for enhancement of NeuAc synthesis. The microbial source of neuC and neuB was optimized, and their expression was fine-tuned. In addition, glycerol as the carbon source showed a much better effect on NeuAc synthesis than glucose. The final engineered strain produced 7.02 g/L NeuAc by shake-flask cultivation. The titer was enhanced to 46.92 g/L by fed-batch cultivation, with the productivity of 0.82 g/L/h and 1.05 g/g DCW.


Subject(s)
Acetylglucosamine , N-Acetylneuraminic Acid , Humans , Acetylglucosamine/metabolism , Biosynthetic Pathways , Escherichia coli/genetics , Escherichia coli/metabolism , Metabolic Engineering , Uridine Diphosphate/metabolism
7.
Int J Biol Macromol ; 231: 123186, 2023 Mar 15.
Article in English | MEDLINE | ID: mdl-36627034

ABSTRACT

To improve the antibacterial and physical properties of corn starch/chitosan films effectively, starch/chitosan/polyethyleneimine (PEI) blend films crosslinked by citric acid (labeled SCPC) with different contents (2.5 %, 5.0 %, 7.5 % and 10.0 %) were prepared by the solution casting method. The films were characterized in detail. The results showed that the addition of 3.75 % PEI improved the tensile strength and elongation at break of the starch/chitosan film simultaneously, but the thermal stability decreased. After CA was incorporated, the tensile strength and thermal stability of the films were enhanced significantly. FTIR, XRD, and 1H NMR analyses revealed strong interactions among CA, PEI and starch-chitosan. All films showed smooth and homogenous fragile cross-sections. The water vapor permeability of the film decreased overall after PEI and CA addition. Moisture uptake (MU) accelerated after PEI addition, but the balanced MU was reduced by CA cross-linking. All films showed an inhibitory effect on E. coli and S. aureus, and CA incorporation significantly improved the inhibition ability of the film. The SCPC film with 3.75 % PEI and 5.0 % CA addition has the best comprehensive properties, which endowed its application in the bioactive packaging field.


Subject(s)
Chitosan , Starch , Starch/chemistry , Chitosan/chemistry , Zea mays/chemistry , Polyethyleneimine/pharmacology , Escherichia coli , Citric Acid/pharmacology , Staphylococcus aureus , Anti-Bacterial Agents/pharmacology , Permeability , Food Packaging
8.
J Chromatogr Sci ; 61(8): 766-772, 2023 Oct 03.
Article in English | MEDLINE | ID: mdl-36477207

ABSTRACT

A high-performance liquid chromatograph with diode array detector was established for the simultaneous determination of five phenylethanoid glycosides in Syringa pubescens Turcz. The optimal chromatographic conditions were achieved on a Zorbax C18 column using gradient elution with 0.5% aqueous acetic acid and acetonitrile as the mobile phase at the flow rate of 1.0 mL/min. The detection wavelength was developed as follows: 0-10 min, 276 nm; 10-45 min, 332 nm. The validation of the method including linearity, precision, stability, accuracy, repeatability and recovery was tested. The chemometric analysis including hierarchical cluster analysis and principal component analysis was employed to investigate the similarity and difference of samples from different geographical origin. The results revealed that S. pubescens samples were divided into four clusters based on the phenylethanoid glycosides contents. Antioxidant activity of extract was measured using three different methods including α,α-diphenyl-ß-picrylhydrazyl and 2,2-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) radical scavenging assays, and ferric reducing antioxidant power assay. Furthermore, different phenylethanoid glycosides exhibited different contribution to antioxidant capacities. This study provides a foundation for the quality evaluation and offers scientific data for the utilization of S. pubescens resources.


Subject(s)
Glycosides , Syringa , Glycosides/analysis , Antioxidants , Plant Extracts/chemistry , Chromatography, High Pressure Liquid/methods , China
9.
Biotechnol Adv ; 62: 108058, 2023.
Article in English | MEDLINE | ID: mdl-36372185

ABSTRACT

Human milk oligosaccharides (HMOs), the third major solid component in breast milk, are recognized as the first prebiotics for health benefits in infants. Sialylated HMOs are an important type of HMOs, accounting for approximately 13% of total HMOs. 3'-Sialyllactose (3'-SL) and 6'-sialyllactose (6'-SL) are two simplest sialylated HMOs. Both SLs display promising prebiotic effects, especially in promoting the proliferation of bifidobacteria and shaping the gut microbiota. SLs exhibit several health effects, including antiadhesive antimicrobial ability, antiviral activity, prevention of necrotizing enterocolitis, immunomodulatory activity, regulation of intestinal epithelial cell response, promotion of brain development, and cognition improvement. Both SLs have been approved as "Generally Recognized as Safe" by the American Food and Drug Administration and are commercially added to infant formula. The biosynthesis of SLs using enzymatic or microbial approaches has been widely studied. The enzymatic synthesis of SLs can be realized by two types of enzymes, sialidases with trans-sialidase activity and sialyltransferases. Microbial synthesis can be achieved by the multiple recombinant bacteria in one-pot reaction, which express the enzymes involved in SL synthesis pathways separately or in combination, or by metabolically engineered strains in a fermentation process. In this article, the physiological properties of 3'-SL and 6'-SL are summarized in detail and the biosynthesis of these SLs via enzymatic and microbial synthesis is comprehensively reviewed.


Subject(s)
Milk, Human , Oligosaccharides , Female , Humans , Infant, Newborn , Milk, Human/metabolism , Oligosaccharides/metabolism , Lactose , Prebiotics
10.
Transl Vis Sci Technol ; 11(10): 27, 2022 10 03.
Article in English | MEDLINE | ID: mdl-36255358

ABSTRACT

Purpose: Diabetic macular edema (DME) is the leading cause of vision loss and blindness among working-age adults. Although current intravitreal anti-vascular endothelial growth factor (VEGF) therapies improve vision for many patients with DME, approximately half do not achieve the visual acuity required to drive. We therefore sought additional approaches to resolve edema and improve vision for these patients. Methods: We explored direct agonists of Tie2, a receptor known to stabilize vasculature and prevent leakage. We identified a multivalent PEG-Fab conjugate, Tie2.1-hexamer, that oligomerizes Tie2 and drives receptor activation and characterized its activities in vitro and in vivo. Results: Tie2.1-hexamer normalized and stabilized intercellular junctions of stressed endothelial cell monolayers in vitro, suppressed vascular leak in mice under conditions where anti-VEGF alone was ineffective, and demonstrated extended ocular exposure and robust pharmacodynamic responses in non-human primates. Conclusions: Tie2.1-hexamer directly activates the Tie2 pathway, reduces vascular leak, and is persistent within the vitreal humor. Translational Relevance: Our study presents a promising potential therapeutic for the treatment of DME.


Subject(s)
Diabetes Mellitus , Diabetic Retinopathy , Macular Edema , Mice , Animals , Macular Edema/drug therapy , Macular Edema/etiology , Diabetic Retinopathy/drug therapy , Endothelial Growth Factors/therapeutic use , Visual Acuity , Vision Disorders/complications , Vision Disorders/drug therapy , Blindness/complications
11.
ACS Synth Biol ; 11(8): 2837-2845, 2022 08 19.
Article in English | MEDLINE | ID: mdl-35802806

ABSTRACT

3'-Sialyllactose (3'-SL) is one of the most important and simplest sialylated human milk oligosaccharides. In this study, a plasmid-based pathway optimization along with chromosomal integration strategies was applied for 3'-SL production. Specifically, the precursor CMP-Neu5Ac synthesis pathway genes and α2,3-sialyltransferase-encoding gene were introduced into Escherichia coli BL21(DE3)ΔlacZ to realize 3'-SL synthesis. Genes nanA and nanK involved in Neu5Ac catabolism were further deleted to reduce the metabolic flux of competitive pathway. Several α2,3-sialyltransferases from different species were selected to evaluate the sialylation effect. The precursor pools were balanced and improved by optimizing key enzyme expression involved in the UDP-GlcNAc and CMP-Neu5Ac synthesis pathway. Finally, an additional α2,3-sialyltransferase expression cassette was integrated into chromosome to maximize 3'-SL synthesis, and 4.5 g/L extracellular 3'-SL was produced at a shake-flask level. The extracellular 3'-SL concentration was raised to 23.1 g/L in a 5 L bioreactor fermentation, which represents the highest extracellular value ever reported.


Subject(s)
Escherichia coli , Sialyltransferases , Escherichia coli/metabolism , Humans , Milk, Human/metabolism , Oligosaccharides/metabolism , Sialyltransferases/genetics , Sialyltransferases/metabolism
12.
Appl Microbiol Biotechnol ; 106(9-10): 3829-3836, 2022 May.
Article in English | MEDLINE | ID: mdl-35536403

ABSTRACT

The limited bioavailability of PAHs in non-aqueous phase liquid (NAPL) limits their degradation. The biodegradation of phenanthrene in n-tetradecane by hydrophilic bacterium Moraxella sp. CFP312 was studied with the assistance of two polymers, chitosan and carboxymethyl cellulose (CMC). Both chitosan and CMC improved the cell hydrophobicity of CFP312 and increased the contact angle of CFP312 cells from 30.4 to 78.5 and 88.5, respectively. However, CMC increased the degradation ratio of phenanthrene from 45 to nearly 100%, while chitosan did not cause any improvement. We found that CMC was more effective than chitosan in promoting CFP312 to stabilize Pickering emulsion. In the bacteria-CMC complex system, oil was dispersed into small droplets to obtain a high emulsification index and large specific surface area. Moreover, according to the microscopic image of the bacteria-CMC emulsion droplet, we observed that the droplet surface was tightly covered by the CFP312 cells. Therefore, CFP312 cells joined with CMC can utilize phenanthrene in oil phase at the oil-water interface. This study will offer a new strategy for effective microbial degradation of hydrophobic compounds in NAPLs by hydrophilic bacteria. KEY POINTS: • Biodegradation of phenanthrene in Pickering emulsions • Pickering emulsions stabilized by hydrophilic CFP312 joined with CMC. • Phenanthrene was degraded by CFP312 at oil-water interface.


Subject(s)
Chitosan , Phenanthrenes , Bacteria/metabolism , Carboxymethylcellulose Sodium/metabolism , Chitosan/chemistry , Emulsions/chemistry , Phenanthrenes/metabolism , Water/chemistry
13.
Sheng Wu Gong Cheng Xue Bao ; 37(10): 3696-3707, 2021 Oct 25.
Article in Chinese | MEDLINE | ID: mdl-34708621

ABSTRACT

Polycyclic aromatic hydrocarbons (PAHs) are a class of common environmental pollutants that pose threats to human health. In this study, a mesophilic bacterial strain CFP312 (grown at 15-37 °C, optimal at 30 °C) was isolated from PAHs-contaminated soil samples. It was identified as Moraxella sp. by morphological observation, physiological and biochemical test, and 16S rRNA gene phylogeny analysis. This is the first reported PAHs degrading strains in Moraxella. Degradation analysis showed that 84% and 90% of the loaded phenanthrene (400 mg/L) were degraded within 48 h and 60 h, and the degradation rates reached 1.21 and 1.29 mg/(L·h), respectively. During the degradation of phenanthrene, phenanthrene-3,4-dihydrodiol was detected as an intermediate. Based on this, it was proposed that double oxygenation at the positions 3 and 4 of phenanthrene was the first step of biodegradation. Adaptability of strain CFP312 to different enhanced phenanthrene-degradation systems was tested in aqueous-organic system, micellar aqueous system, and cloud point system. Strain CFP312 showed good adaptability to different systems. In addition, the bacterium can rapidly degrade the phenanthrene in contaminated soil in slurry-aqueous system, indicating great potential in environmental remediation.


Subject(s)
Phenanthrenes , Polycyclic Aromatic Hydrocarbons , Soil Pollutants , Biodegradation, Environmental , Humans , RNA, Ribosomal, 16S/genetics , Soil Microbiology
14.
J Cell Mol Med ; 25(16): 7796-7808, 2021 08.
Article in English | MEDLINE | ID: mdl-34184814

ABSTRACT

The expression pattern, biological functions and the related mechanisms of the ring finger protein 19A (RNF19A) in non-small cell lung cancer (NSCLC) remain poorly understood. This study aimed to explore the role of RNF19A, as well as the underlying potential mechanism, in the development of NSCLC. Here, we found that RNF19A was overexpressed in NSCLC tissues, and RNF19A expression in NSCLC tissue samples was associated with NSCLC carcinogenesis and poor outcome. RNF19A promoted the proliferation of NSCLC cells and inhibited apoptosis. RNF19A reduced p53, p21 and BAX expression and induced Cyclin D1, CDK4, CDK6 and BCL2 expression. The inhibitory effect of RNF19A knockdown on proliferation was partially rescued by p53 silencing. RNF19A interacted with p53, shortened p53 half-life and mediated p53 ubiquitin-degradation. Collectively, we suggest that RNF19A plays a critical oncogenic role in lung carcinogenesis by disrupting the function of p53. RNF19A may serve as a new biomarker and/or target for NSCLC management.


Subject(s)
Biomarkers, Tumor/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Gene Expression Regulation, Neoplastic , Proteolysis , Tumor Suppressor Protein p53/metabolism , Ubiquitin-Protein Ligases/metabolism , Ubiquitination , Apoptosis , Biomarkers, Tumor/metabolism , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/metabolism , Cell Line, Tumor , Cell Proliferation , Female , Humans , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Male , Middle Aged , Survival Rate , Tumor Suppressor Protein p53/genetics , Ubiquitin-Protein Ligases/genetics
15.
Anal Bioanal Chem ; 413(14): 3801-3811, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33961103

ABSTRACT

Salmonella is a prevalent pathogen causing serious morbidity and mortality worldwide. There are over 2600 serovars of Salmonella. Among them, Salmonella Enteritidis, Salmonella Typhimurium, and Salmonella Paratyphi were reported to be the most common foodborne pathogenic serovars in the EU and China. In order to provide a more efficient approach to detect and distinguish these serovars, a new analytical method was developed by combining surface-enhanced Raman spectroscopy (SERS) with multi-scale convolutional neural network (CNN). We prepared 34-nm gold nanoparticles (AuNPs) as the label-free Raman substrate, measured 1854 SERS spectra of these three Salmonella serovars, and then proposed a multi-scale CNN model with three parallel CNNs to achieve multi-dimensional extraction of SERS spectral features. We observed the impact of the number of iterations and training samples on the recognition accuracy by changing the ratio of the number of the training and testing sets. By comparing the calculated data with experimental one, it was shown that our model could reach recognition accuracy more than 97%. These results indicate that it was not only feasible to combine SERS spectroscopy with multi-scale CNN for Salmonella serotype identification, but also for other pathogen species and serovar identifications.


Subject(s)
Salmonella Infections/microbiology , Salmonella/chemistry , Spectrum Analysis, Raman/methods , Gold/chemistry , Humans , Metal Nanoparticles/chemistry , Neural Networks, Computer , Salmonella/classification , Salmonella/isolation & purification , Time Factors
16.
Cancer Sci ; 112(6): 2210-2222, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33754417

ABSTRACT

Mitotic spindle organizing protein 2A (MZT2A) is localized at the centrosome and regulates microtubule nucleation activity in cells. This study assessed the role of MZT2A in non-small-cell lung cancer (NSCLC). Differential MZT2A expression was bioinformatically assessed using TCGA database, the GEPIA database, and Kaplan-Meier survival data to determine the association between MZT2A expression and NSCLC prognosis. Furthermore, NSCLC tissue specimens were evaluated by immunohistochemistry. MZT2A was overexpressed or knocked down in NSCLC cells using cDNA and siRNA, respectively. The cells were subjected to various assays and treated with the selective Akt inhibitor LY294002 or co-transfected with galectin-3-binding protein (LGALS3BP) siRNA. MZT2A mRNA and protein levels were upregulated in NSCLC lesions and MTZ2A expression was associated with poor NSCLC prognosis. MZT2A protein was also highly expressed in NSCLC cells compared with the expression in normal bronchial cells. MZT2A expression promoted NSCLC cell viability and invasion, whereas MTZ2A siRNA had the opposite effect on NSCLC cells in vitro. At the protein level, MZT2A induced Akt phosphorylation, promoting NSCLC proliferation and invasion (but the selective Akt inhibitor blocked these effects) through upregulation of LGALS3BP via the MTZ2A MOZART2 domain, whereas LGALS3BP siRNA suppressed MTZ2A activity in NSCLC cells. The limited in vivo experiments confirmed the in vitro data. In conclusion, MZT2A exhibits oncogenic activity by activating LGALS3BP and Akt in NSCLC. Future studies will assess MTZ2A as a biomarker to predict NSCLC prognosis or as a target in the control of NSCLC progression.


Subject(s)
Carcinoma, Non-Small-Cell Lung/pathology , Lung Neoplasms/pathology , Microtubule-Associated Proteins/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Animals , Antigens, Neoplasm/genetics , Antigens, Neoplasm/metabolism , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/metabolism , Cell Line, Tumor , Cell Survival , Gene Expression Regulation, Neoplastic , Humans , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Mice , Microtubule-Associated Proteins/chemistry , Microtubule-Associated Proteins/genetics , Neoplasm Invasiveness , Phosphorylation , Prognosis , Protein Domains , Signal Transduction
17.
Clin Ophthalmol ; 14: 4385-4393, 2020.
Article in English | MEDLINE | ID: mdl-33364743

ABSTRACT

BACKGROUND: The Early Treatment Diabetic Retinopathy Study Diabetic Retinopathy Severity Scale (DRSS) is a standard approach to measure diabetic retinopathy (DR) severity. Many clinical trials evaluating drug intervention for DR rely upon demonstration of a therapeutic effect through measurement of a 2- or 3-step improvement or progression on the DRSS; however, these binary endpoints require a relatively large sample size for a reliable estimate of therapeutic efficacy, especially when the SOC (eg, anti-VEGF) is used as a control. This study was designed to evaluate the sensitivity and statistical efficiency of detecting a drug effect in DR across different DRSS endpoints, and present alternative analytical approaches to enable smaller-size DR trials for detecting a reliable efficacy signal before moving into larger confirmatory DR trials. METHODS: Data from two randomized, double-blinded, controlled Phase III trials, that enrolled patients with decreased vision due to center-involved DME and the presence of macular edema documented on optical coherence tomography and simulated data, were used for this study. Changes in DRSS steps during a 3-month period from patients (n=205) with no active intervention were used to confirm the reliability of DRSS outcomes. A simulation study compared sensitivity and statistical efficiency across different DRSS endpoints. RESULTS: The standard deviation of step change between baseline and month 3 DRSS across different steps at baseline were all within 1 step, confirming the reliability of DRSS measure by each step. Efficiency of detecting reliable therapeutic efficacy was augmented when treatment effect in improvement and progression was evaluated together; highest sensitivity was observed when change in DRSS steps was used directly as an endpoint. CONCLUSION: DRSS step change may provide more robust sensitivity and statistical efficiency. It is therefore a more cost-effective endpoint for the detection of therapeutic efficacy signal in drug discoveries in DR.

18.
Anal Bioanal Chem ; 412(4): 983-991, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31848668

ABSTRACT

Hemoglobin (Hb)-imprinted poly(ionic liquid)s (HIPILs) were prepared on the surface of Au electrode modified with gold nanodendrites (Au/ND/HIPILs). HIPILs were synthesized with 1-vinyl-3-propyl imidazole sulfonate ionic liquids as functional monomers via electrochemically mediated atom transfer radical polymerization (eATRP) catalyzed by Hb. The Au/ND/HIPILs electrode was examined by cyclic voltammetry (CV), scanning electron microscope (SEM), and X-ray photoelectron spectroscopy (XPS). The Au/ND/HIPILs electrode was also used as an electrochemical sensor to determine Hb by differential pulse voltammetry (DPV). Under the optimal conditions, the detection range of Hb was from 1.0 × 10-14 to 1.0 × 10-4 mg/mL with a limit of detection of 5.22 × 10-15 mg/mL (S/N = 3). Compared with other methods, the sensor based on poly(ionic liquid)s had the broader linear range and lower detection limit. Graphical Abstract.


Subject(s)
Gold/chemistry , Hemoglobins/analysis , Ionic Liquids/chemistry , Metal Nanoparticles/chemistry , Molecular Imprinting/methods , Animals , Biosensing Techniques/methods , Catalysis , Cattle , Imidazoles/chemistry , Limit of Detection , Polymerization
19.
Chaos ; 29(4): 043102, 2019 Apr.
Article in English | MEDLINE | ID: mdl-31042952

ABSTRACT

In this paper, clustering in the Kuramoto model with second-order coupling is investigated under the bimodal Lorentzian frequency distribution. By linear stability analysis and the Ott-Antonsen ansatz treatment, the critical coupling strength for the synchronization transition is obtained. The theoretical results are further verified by numerical simulations. It has been revealed that various synchronization paths, including the first- and second-order transitions as well as the multiple bifurcations, exist in this system with different parameters of frequency distribution. In certain parameter regimes, the Bellerophon states are observed and their dynamical features are fully characterized.

20.
Invest Ophthalmol Vis Sci ; 59(4): AMD195-AMD201, 2018 03 20.
Article in English | MEDLINE | ID: mdl-30383205

ABSTRACT

Purpose: Geographic atrophy (GA) is an advanced form of age-related macular degeneration. GA often initially spares the center of the fovea, leading to a functional disconnect between reading speed and distance visual acuity. This study was designed to determine the correlation between baseline GA lesion size, change in lesion size, and maximum reading speed (MRS) over 18 months. Methods: Post hoc analysis included US patients from the phase 2 Mahalo study of intravitreal lampalizumab with Minnesota low-vision reading (MNREAD) assessments at baseline and 6, 12, and 18 months. Binocular MRS was assessed using MNREAD Acuity Charts and GA lesion size by fundus autofluorescence. Correlations were estimated using Spearman's rank correlation coefficient. Results: Seventy-seven patients were included in the analysis. Baseline MRS correlated with baseline GA lesion size (correlation coefficient, -0.47; 95% confidence interval, -0.63 to -0.28; P < 0.0001). In patients with lesions ≥10 mm2 (four disc areas), the proportion reading below a nonfluent level (MRS, <40 words/min) at baseline (26.5%) increased to 64.7% by 18 months, versus patients with lesions <10 mm2 (baseline, 9.3%; 18 months, 7.0%). MRS declined by a median of 40.9% (interquartile range [IQR], -70.2 to -6.9) in patients with ≥2.5 mm2 lesion growth versus 8.2% (IQR, -34.6 to 11.0) in patients with <2.5 mm2 lesion growth from baseline to 18 months. Conclusions: These findings suggest that baseline GA lesion size and magnitude of lesion growth are associated with a decline in MRS over time and support the use of MRS as an evaluation of functional vision in patients with GA.


Subject(s)
Geographic Atrophy/physiopathology , Macular Degeneration/complications , Reading , Vision, Low/physiopathology , Aged , Aged, 80 and over , Female , Geographic Atrophy/drug therapy , Geographic Atrophy/etiology , Humans , Immunoglobulin Fab Fragments/therapeutic use , Intravitreal Injections , Male , Single-Blind Method , Vision, Binocular/physiology , Visual Acuity/physiology
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