scholarly journals Dietary Nanoparticles Interact with Gluten Peptides and Alter the Intestinal Homeostasis Increasing the Risk of Celiac Disease

2021 ◽  
Vol 22 (11) ◽  
pp. 6102
Author(s):  
Clara Mancuso ◽  
Francesca Re ◽  
Ilaria Rivolta ◽  
Luca Elli ◽  
Elisa Gnodi ◽  
...  
Keyword(s):  
Celiac Disease ◽  
Metallic Nanoparticles ◽  
Synergistic Effects ◽  
Food Sector ◽  
Intestinal Homeostasis ◽  
Gluten Peptides ◽  
Transmission Electron ◽  
Duodenal Biopsies ◽  
Junction Proteins

The introduction of metallic nanoparticles (mNPs) into the diet is a matter of concern for human health. In particular, their effect on the gastrointestinal tract may potentially lead to the increased passage of gluten peptides and the activation of the immune response. In consequence, dietary mNPs could play a role in the increasing worldwide celiac disease (CeD) incidence. We evaluated the potential synergistic effects that peptic-tryptic-digested gliadin (PT) and the most-used food mNPs may induce on the intestinal mucosa. PT interaction with mNPs and their consequent aggregation was detected by transmission electron microscopy (TEM) analyses and UV–Vis spectra. In vitro experiments on Caco-2 cells proved the synergistic cytotoxic effect of PT and mNPs, as well as alterations in the monolayer integrity and tight junction proteins. Exposure of duodenal biopsies to gliadin plus mNPs triggered cytokine production, but only in CeD biopsies. These results suggest that mNPs used in the food sector may alter intestinal homeostasis, thus representing an additional environmental risk factor for the development of CeD.

scholarly journals Inhibition of Estrogenic Response of Yeast Screen Assay by Exposure to Non-Lethal Levels of Metallic Nanoparticles

2020 ◽  
Vol 10 (11) ◽  
pp. 3796
Author(s):  
Byoung-cheun Lee ◽  
Cuong N. Duong ◽  
Jungkon Kim ◽  
Suejin Kim ◽  
Ig-chun Eom ◽  
...  
Keyword(s):  
Metallic Nanoparticles ◽  
Estrogenic Activity ◽  
Endocrine Disrupting Compounds ◽  
Cell Organelles ◽  
Yeast Saccharomyces Cerevisiae ◽  
Tem Analysis ◽  
Environmental Media ◽  
Transmission Electron ◽  
17Β Estradiol

In order to investigate the effects of metallic nanoparticles (NPs) on the performance of in vitro bioassay, zinc oxide NP (ZnO NP), aluminum oxide NP (Al2O3 NP), bare silver NP (Ag NP), and Ag NP capped with citrate (Agcit NP) were evaluated with yeast (Saccharomyces cerevisiae Y190) two-hybrid system (YES assay), carrying Japanese medaka estrogen receptors (mERs) in the presence of 17β-estradiol (E2, 10−6 M), a reference chemical for estrogenic activity. The distribution of NPs in the yeast was also examined by field-emission transmission electron microscopy (FE-TEM). The results show that TEM analysis revealed that NPs were present inside the yeast and accumulated deep inside the cell organelles, suggesting that cell death was caused by NPs. However, despite no significant change of mortality, the E2 estrogenic activities in yeast exposed to ZnO NP and Al2O3 NP were dose-dependently reduced. For Ag NP and Agcit NP, such phenomenon observed in the exposure of ZnO NP and Al2O3 NP did not occur. From the observations, we found that ZnO NP and Al2O3 NP in the environmental media could result in underestimated estrogenicity of endocrine-disrupting compounds when evaluated by YES assay.

scholarly journals Cocktail Therapy of Fosthiazate and Cupric-Ammoniun Complex for Citrus Huanglongbing

2021 ◽  
Vol 12 ◽  
Author(s):  
Jingwei Duan ◽  
Xue Li ◽  
Junzhe Zhang ◽  
Baoping Cheng ◽  
Shuhan Liu ◽  
...  
Keyword(s):  
Synergistic Effects ◽  
Starch Accumulation ◽  
Bacterial Disease ◽  
Tree Roots ◽  
Tylenchulus Semipenetrans ◽  
Transmission Electron ◽  
Citrus Root ◽  
Citrus Huanglongbing ◽  
Liberibacter Asiaticus

Huanglongbing (HLB) is a destructive citrus bacterial disease caused by Candidatus Liberibacter asiaticus (Ca.Las) and cannot be cured by current pesticides. Root lesion and Tylenchulus semipenetrans juveniles were observed in HLB-affected citrus tree roots. We hypothesize that root treatment with fosthiazate (FOS) and Cupric-Ammonium Complex (CAC) will improve the root growth and inhibit HLB. CAC is a broad spectrum fungicide and can promote growth of crops. FOS kills Tylenchulus semipenetrans and protects roots from damage by harmful bacteria such as Ca.Las. After 90 days of combination treatment of FOS and CAC through root drenches, the citrus grew new roots and its leaves changed their color to green. The inhibition rate of Ca.Las reached more than 90%. During treatment process, the chlorophyll content and the root vitality increased 396 and 151%, respectively, and starch accumulation decreased by 88%. Transmission electron microscopy (TEM) and plant tissue dyeing experiments showed that more irregular swollen starch granules existed in the chloroplast thylakoid system of the HLB-infected leaves. This is due to the blocking of their secretory tissue by starch. TEM and flow cytometry experiments in vitro showed the synergistic effects of FOS and CAC. A transcriptome analysis revealed that the treatment induced the differential expression of the genes which involved 103 metabolic pathways. These results suggested that the cocktail treatment of FOS and CAC may effectively kill various pathogens including Ca.Las on citrus root and thus effectively control HLB.

scholarly journals Chitosan-Stabilized Ag Nanoparticles with Superior Biocompatibility and Their Synergistic Antibacterial Effect in Mixtures with Essential Oils

Nanomaterials ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 826 ◽  
Author(s):  
Ludmila Cinteza ◽  
Cristina Scomoroscenco ◽  
Sorina Voicu ◽  
Cristina Nistor ◽  
Sabina Nitu ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Essential Oils ◽  
Metallic Nanoparticles ◽  
Synergistic Effects ◽  
Medical Application ◽  
Colloidal Dispersion ◽  
Multidrug Resistant ◽  
Antimicrobial Activities ◽  
Promising Alternative

Silver nanoparticles (AgNPs) are considered a promising alternative to the use of antibiotics in fighting multidrug-resistant pathogens. However, their use in medical application is hindered by the public concern regarding the toxicity of metallic nanoparticles. In this study, rationally designed AgNP were produced, in order to balance the antibacterial activity and toxicity. A facile, environmentally friendly synthesis was used for the electrochemical fabrication of AgNPs. Chitosan was employed as the capping agent, both for the stabilization and to improve the biocompatibility. Size, morphology, composition, capping layer, and stability of the synthesized nanoparticles were characterized. The in vitro biocompatibility and antimicrobial activities of AgNPs against common Gram-negative and Gram-positive bacteria were evaluated. The results revealed that chitosan-stabilized AgNPs were nontoxic to normal fibroblasts, even at high concentrations, compared to bare nanoparticles, while significant antibacterial activity was recorded. The silver colloidal dispersion was further mixed with essential oils (EO) to increase the biological activity. Synergistic effects at some AgNP–EO ratios were observed, as demonstrated by the fractionary inhibitory concentration values. Our results reveal that the synergistic action of both polymer-stabilized AgNPs and essential oils could provide a significant efficiency against a large variety of microorganisms, with minimal side effects.

scholarly journals A novel in vitro platform for the study of SN38-induced mucosal damage and the development of Toll-like receptor 4-targeted therapeutic options

2016 ◽  
Vol 241 (13) ◽  
pp. 1386-1394 ◽  
Author(s):  
Hannah R Wardill ◽  
Rachel J Gibson ◽  
Ysabella ZA Van Sebille ◽  
Kate R Secombe ◽  
Richard M Logan ◽  
...  
Keyword(s):  
Tight Junction ◽  
Tight Junctions ◽  
Mucosal Damage ◽  
Toll Like Receptor ◽  
Tight Junction Proteins ◽  
T84 Cells ◽  
Toll Like Receptor 4 ◽  
Transmission Electron ◽  
Junction Proteins

Tight junction and epithelial barrier disruption is a common trait of many gastrointestinal pathologies, including chemotherapy-induced gut toxicity. Currently, there are no validated in vitro models suitable for the study of chemotherapy-induced mucosal damage that allow paralleled functional and structural analyses of tight junction integrity. We therefore aimed to determine if a transparent, polyester membrane insert supports a polarized T84 monolayer with the phenotypically normal tight junctions. T84 cells (passage 5–15) were seeded into either 0.6 cm2, 0.4 µm pore mixed-cellulose transwell hanging inserts or 1.12 cm2, 0.4 µm pore polyester transwell inserts at varying densities. Transepithelial electrical resistance was measured daily to assess barrier formation. Immunofluoresence for key tight junction proteins (occludin, zonular occludens-1, claudin-1) and transmission electron microscopy were performed to assess tight junction integrity, organelle distribution, and polarity. Reverse transcription-polymerase chain reaction was performed to determine expression of toll-like receptor 4 (TLR4). Liquid chromatography was also conducted to assess SN38 degradation in this model. Polyester membrane inserts support a polarized T84 phenotype with functional tight junctions in vitro. Transmission electron microscopy indicated polarity, with apico-laterally located tight junctions. Immunofluorescence showed membranous staining for all tight junction proteins. No internalization was evident. T84 cells expressed TLR4, although this was significantly lower than levels seen in HT29 cells ( P = .0377). SN38 underwent more rapid degradation in the presence of cells (−76.04 ± 1.86%) compared to blank membrane (−48.39 ± 4.01%), indicating metabolic processes. Polyester membrane inserts provide a novel platform for paralleled functional and structural analysis of tight junction integrity in T84 monolayers. T84 cells exhibit the unique ability to metabolize SN38 as well as expressing TLR4, making this an excellent platform to study clinically relevant therapeutic interventions for SN38-induced mucosal damage by targeting TLR4.

scholarly journals Collagen immobilization on ultra-thin nanofiber membrane to promote in vitro endothelial monolayer formation

2019 ◽  
Vol 10 ◽  
pp. 204173141988783 ◽  
Author(s):  
Byeong-ung Park ◽  
Sang Min Park ◽  
Kyoung-pil Lee ◽  
Seong Jin Lee ◽  
Yu Eun Nam ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Endothelial Cell ◽  
Cost Effective ◽  
Original Structure ◽  
Nanofiber Membrane ◽  
Cell Homeostasis ◽  
Transmission Electron ◽  
Collagen Immobilization ◽  
Junction Proteins

The endothelialization on the poly (ε-caprolactone) nanofiber has been limited due to its low hydrophilicity. The aim of this study was to immobilize collagen on an ultra-thin poly (ε-caprolactone) nanofiber membrane without altering the nanofiber structure and maintaining the endothelial cell homeostasis on it. We immobilized collagen on the poly (ε-caprolactone) nanofiber using hydrolysis by NaOH treatment and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/sulfo- N-hydroxysulfosuccinimide reaction as a cost-effective and stable approach. NaOH was first applied to render the poly (ε-caprolactone) nanofiber hydrophilic. Subsequently, collagen was immobilized on the surface of the poly (ε-caprolactone) nanofibers using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/sulfo- N-hydroxysulfosuccinimide. Scanning electron microscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, and fluorescence microscopy were used to verify stable collagen immobilization on the surface of the poly (ε-caprolactone) nanofibers and the maintenance of the original structure of poly (ε-caprolactone) nanofibers. Furthermore, human endothelial cells were cultured on the collagen-immobilized poly (ε-caprolactone) nanofiber membrane and expressed tight junction proteins with the increase in transendothelial electrical resistance, which demonstrated the maintenance of the endothelial cell homeostasis on the collagen-immobilized-poly (ε-caprolactone) nanofiber membrane. Thus, we expected that this process would be promising for maintaining cell homeostasis on the ultra-thin poly (ε-caprolactone) nanofiber scaffolds.

scholarly journals In Vitro Destruction of Pathogenic Bacterial Biofilms by Bactericidal Metallic Nanoparticles via Laser-Induced Forward Transfer

Nanomaterials ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 2259
Author(s):  
Alena Nastulyavichus ◽  
Eteri Tolordava ◽  
Andrey Rudenko ◽  
Darya Zazymkina ◽  
Pavel Shakhov ◽  
...  
Keyword(s):  
Metallic Nanoparticles ◽  
Cost Effective ◽  
Treatment Method ◽  
Bacterial Biofilms ◽  
Polymeric Substrate ◽  
X Ray ◽  
Transmission Electron ◽  
Forward Transfer ◽  
Bactericidal Efficiency

A novel, successful method of bactericidal treatment of pathogenic bacterial biofilms in vitro by laser-induced forward transfer of metallic nanoparticles from a polyethylene terephthalate polymeric substrate was suggested. Transferred nanoparticles were characterized by scanning and transmission electron microscopy, energy-dispersive X-ray and Raman spectroscopy. The antibacterial modality of the method was tested on Gram-positive (Staphylococcus aureus) and Gram-negative (Pseudomonas Aeruginosa) bacterial biofilms in vitro, revealing their complete destruction. The proposed simple, cost-effective and potentially mobile biofilm treatment method demonstrated its high and broad bactericidal efficiency.

scholarly journals A Guide for Using Transmission Electron Microscopy for Studying the Radiosensitizing Effects of Gold Nanoparticles In Vitro

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 859
Author(s):  
Ioanna Tremi ◽  
Sophia Havaki ◽  
Sofia Georgitsopoulou ◽  
Nefeli Lagopati ◽  
Vasilios Georgakilas ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Gold Nanoparticles ◽  
Metallic Nanoparticles ◽  
Cellular Localization ◽  
Optimal Dose ◽  
Enhancement Effect ◽  
Nanoparticle Distribution ◽  
Transmission Electron

The combined effects of ionizing radiation (IR) with high-z metallic nanoparticles (NPs) such as gold has developed a growing interest over the recent years. It is currently accepted that radiosensitization is not only attributed to physical effects but also to underlying chemical and biological mechanisms’ contributions. Low- and high-linear energy transfer (LET) IRs produce DNA damage of different structural types. The combination of IR with gold nanoparticles may increase the clustering of energy deposition events in the vicinity of the NPs due to the production mainly of photoelectrons and Auger electrons. Biological lesions of such origin for example on DNA are more difficult to be repaired compared to isolated lesions and can augment IR’s detrimental effects as shown by numerous studies. Transmission electron microscopy (TEM) offers a unique opportunity to study the complexity of these effects on a very detailed cellular level, in terms of structure, including nanoparticle uptake and damage. Cellular uptake and nanoparticle distribution inside the cell are crucial in order to contribute to an optimal dose enhancement effect. TEM is mostly used to observe the cellular localization of nanoparticles. However, it can also provide valuable insights on the NPs’ radiosensitization pathways, by studying the biochemical mechanisms through immunogold-labelling of antigenic sites at ultrastructural level under high resolution and magnification. Here, our goal is to describe the possibilities, methodologies and proper use of TEM in the interest of studying NPs-based radiosensitization mechanisms.

Maytansine-Induced Mitotic Arrest in Human Lymphoblasts

1977 ◽  
Vol 35 ◽  
pp. 460-461
Author(s):  
Tai-Te Chao ◽  
John Sullivan ◽  
Awtar Krishan
Keyword(s):  
Electron Microscopy ◽  
Cell Cycle ◽  
Transmission Electron Microscopy ◽  
Tubulin Polymerization ◽  
Vinca Alkaloids ◽  
Antimitotic Activity ◽  
Transmission Electron ◽  
Flow Microfluorometry ◽  
Brain Tubulin

Maytansine, a novel ansa macrolide (1), has potent anti-tumor and antimitotic activity (2, 3). It blocks cell cycle traverse in mitosis with resultant accumulation of metaphase cells (4). Inhibition of brain tubulin polymerization in vitro by maytansine has also been reported (3). The C-mitotic effect of this drug is similar to that of the well known Vinca- alkaloids, vinblastine and vincristine. This study was carried out to examine the effects of maytansine on the cell cycle traverse and the fine struc- I ture of human lymphoblasts.Log-phase cultures of CCRF-CEM human lymphoblasts were exposed to maytansine concentrations from 10-6 M to 10-10 M for 18 hrs. Aliquots of cells were removed for cell cycle analysis by flow microfluorometry (FMF) (5) and also processed for transmission electron microscopy (TEM). FMF analysis of cells treated with 10-8 M maytansine showed a reduction in the number of G1 cells and a corresponding build-up of cells with G2/M DNA content.

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