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1.
J Oleo Sci ; 73(6): 857-863, 2024.
Article in English | MEDLINE | ID: mdl-38825539

ABSTRACT

The hybridization of lipids with graphene is expected to produce a promising, novel biomaterial. However, there are limited examples of the covalent introduction of lipid molecules, especially the immobilization of lipid molecules, onto graphene on a substrate. Therefore, we investigated the hybridization of a silane coupling agent having phospholipid moieties with graphene oxide on substrates prepared by photo-oxidation using chlorine dioxide. Three silane coupling agents with different carbon chain lengths (C4, C6, C8) were synthesized and phospholipid molecules were introduced onto graphene on a substrate. Phospholipid-immobilized graphene on a grid for TEM (transmission electron microscope) was used for EM analysis of proteins (glyceraldehyde 3-phosphate dehydrogenase and ß-galactosidase), enabling the observation of sufficient particles compared to the conventional graphene grid.


Subject(s)
Graphite , Phospholipids , Silanes , Graphite/chemistry , Phospholipids/chemistry , Silanes/chemistry , beta-Galactosidase/metabolism , Microscopy, Electron, Transmission , Oxidation-Reduction , Biocompatible Materials/chemistry , Biocompatible Materials/chemical synthesis
2.
BMC Oral Health ; 24(1): 650, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38824555

ABSTRACT

BACKGROUND: The formation of white spots, which represent early carious lesions, is a major issue with fixed orthodontics. The addition of remineralizing agents to orthodontic adhesives may prevent the formation of white spots. The aim of this study was to produce a composite orthodontic adhesive combined with nano-bioactive glass-silver (nBG@Ag) for bracket bonding to enamel and to investigate its cytotoxicity, antimicrobial activity, remineralization capability, and bond strength. METHODS: nBG@Ag was synthesized using the sol-gel method, and characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy with an attenuated total reflectance attachment (ATR-FTIR). The cytotoxicity test (MTT) and antimicrobial activity of adhesives containing 1%, 3%, and 5% (wt/wt) nBG@Ag were evaluated, and the shear bond strength of the adhesives was measured using a universal testing machine. Remineralization was assessed through microhardness testing with a Vickers microhardness tester and scanning electron microscopy (SEM). Statistical analyses were conducted using the Shapiro-Wilk test, Levene test, one-way ANOVA, Robust-Welch test, Tukey HSD method, and two-way ANOVA. RESULTS: The biocompatibility of the adhesives was found to be high, as confirmed by the lack of significant differences in the cytotoxicity between the sample and control groups. Discs made from composites containing nBG@Ag exhibited a significant reduction in the growth of Streptococcus mutans (p < 0.05), and the antibacterial activity increased with higher percentages of nBG@Ag. The shear bond strength of the adhesives decreased significantly (p < 0.001) after the addition of nanoparticles, but it remained above the recommended value. The addition of nBG@Ag showed improvement in the microhardness of the teeth, although the differences in microhardness between the study groups were not statistically significant. The formation of hydroxyapatite deposits on the tooth surface was confirmed through SEM and energy-dispersive X-ray spectroscopy (EDX). CONCLUSION: Adding nBG@Ag to orthodontic adhesives can be an effective approach to enhance antimicrobial activity and reduce enamel demineralization around the orthodontic brackets, without compromising biocompatibility and bond strength.


Subject(s)
Anti-Bacterial Agents , Dental Cements , Orthodontic Brackets , Silver , Tooth Remineralization , Anti-Bacterial Agents/pharmacology , Silver/pharmacology , Tooth Remineralization/methods , Dental Cements/pharmacology , Materials Testing , Nanostructures/therapeutic use , Streptococcus mutans/drug effects , Microscopy, Electron, Scanning , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction , Glass/chemistry , Microscopy, Electron, Transmission , Ceramics , Humans , Composite Resins/pharmacology , Composite Resins/chemistry , Shear Strength , Hardness , Dental Bonding/methods , Dental Enamel/drug effects
3.
Vet Q ; 44(1): 1-11, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38832661

ABSTRACT

Hemorrhagic bowel syndrome (HBS) is characterized by a dissecting intramucosal hematoma at the small bowel, causing obstruction and severe hemorrhage in dairy cattle. Recent investigation revealed the presence of early-stage lesions in cows affected by HBS. These are presumed to be the initial stage of the hematoma, as both share unique dissection of the lamina muscularis mucosae (LMM) as histological hallmark. Early-stage lesions of HBS have not been characterized in greater detail, and neither has the hypothesis of mucosal abrasion as etiology been explored. Therefore, the first objective of the present study was to characterize the morphology of early-stage lesions, by gross examination, histochemistry, immunohistochemistry and transmission electron microscopy. The second objective was to determine the effect of mucosal abrasion to the small intestine in an ex vivo model. A total of 86 early-stage lesions from 10 cows with HBS were characterized. No underlying alterations at the LMM were evident which could explain their occurrence. However, degeneration at the ultrastructural level of the LMM smooth muscle cells was present in 3 of 4 lesions, it is however unclear whether this is primary or secondary. Bacteriological examination did not reveal any association with a specific bacterium. Experimental-induced and early-stage lesions were gross and histologically evaluated and scored in three cows with HBS and seven controls. Experimentally induced lesions in both affected cows and controls, were histologically very similar to the naturally occurring early-stage lesions. Altogether, the results are suggestive for mucosal trauma to play a role in the pathogenesis of HBS.


Subject(s)
Cattle Diseases , Gastrointestinal Hemorrhage , Intestinal Mucosa , Animals , Cattle , Cattle Diseases/pathology , Intestinal Mucosa/pathology , Intestinal Mucosa/ultrastructure , Female , Gastrointestinal Hemorrhage/veterinary , Gastrointestinal Hemorrhage/pathology , Microscopy, Electron, Transmission/veterinary , Intestine, Small/pathology , Immunohistochemistry/veterinary , Intestinal Diseases/veterinary , Intestinal Diseases/pathology
4.
World J Microbiol Biotechnol ; 40(7): 231, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38833075

ABSTRACT

To investigate the mechanism of Triton X-100 (TX-100) reducing the Ag+-resistance of Enterococcus faecalis (E. faecalis), and evaluate the antibacterial effect of TX-100 + Ag+ against the induced Ag+-resistant E. faecalis (AREf). The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of AgNO3 against E. faecalis with/without TX-100 were determined to verify the enhanced antibacterial activity. Transmission electron microscopy (TEM) was used to observe the morphological changes of E. faecalis after treatment. The intra- and extracellular concentration of Ag+ in treated E. faecalis was evaluated using inductively coupled plasma mass spectrometer (ICP-MS). The changes in cell membrane potential and integrity of treated E. faecalis were also observed using the flow cytometer. Moreover, AREf was induced through continuous exposure to sub-MIC of Ag+ and the antibacterial effect of TX-100 + Ag+ on AREf was further evaluated. The addition of 0.04% TX-100 showed maximal enhanced antibacterial effect of Ag+ against E. faecalis. The TEM and ICP-MS results demonstrated that TX-100 could facilitate Ag+ to enter E. faecalis through changing the membrane structure and integrity. Flow cytometry further showed the effect of TX-100 on membrane potential and permeability of E. faecalis. In addition, the enhanced antibacterial effect of TX-100 + Ag+ was also confirmed on induced AREf. TX-100 can facilitate Ag+ to enter E. faecalis through disrupting the membrane structure and changing the membrane potential and permeability, thus reducing the Ag+-resistance of E. faecalis and enhancing the antibacterial effect against either normal E. faecalis or induced AREf.


Subject(s)
Anti-Bacterial Agents , Drug Resistance, Bacterial , Enterococcus faecalis , Microbial Sensitivity Tests , Octoxynol , Silver , Enterococcus faecalis/drug effects , Enterococcus faecalis/growth & development , Octoxynol/pharmacology , Anti-Bacterial Agents/pharmacology , Silver/pharmacology , Cell Membrane/drug effects , Membrane Potentials/drug effects , Microscopy, Electron, Transmission , Silver Nitrate/pharmacology
5.
Environ Geochem Health ; 46(6): 200, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38696110

ABSTRACT

Plant extracts are a great alternative to synthesizing nanoparticles of different metals and metal oxides. This green synthesis method has opened up numerous possibilities in various scientific domains. In present study, Leaf extract from Vitex negundo is a non-deciduous, long-lasting shrub from the Verbenaceae family is used as capping and reducing agents for the synthesis of silver and palladium nanoparticles. The characterization study UV-vis spectrophotometer analysis showed absorbance value around 320 nm which confirming that Ag-Pd nanoparticles have been successfully obtained. Further, SEM is used to investigate the morphology of Ag-Pd NPs, which revealing their spherical and rod-like configuration, aggregation, and the size of the particles are obtained between 50 and 100 nm. The successful synthesis of Ag-Pd NPs was further confirmed by the EDAX chart, which displayed the peak of Ag and Pd at bending energies between 0.5 and 1.5 keV. According to the quantitative study, Ag and Pd ions found about 5.24 and 13.28%, respectively. In addition, surface studies with TEM confirming that synthesized Ag-Pd NPs are predominates with spheres structure morphologies, with sizes averaging 11.20 nm and ranging from 10 to 20 nm. Further, Ag-Pd nanoparticles was applied as potential photocatalyst materials to degrade methylene blue dye and found about 85% of the degradation efficiency within 150 min of the sunlight exposure thus could be used as catalyst to removal of hazardous organic dye molecules.


Subject(s)
Coloring Agents , Metal Nanoparticles , Palladium , Silver , Vitex , Vitex/chemistry , Palladium/chemistry , Silver/chemistry , Metal Nanoparticles/chemistry , Catalysis , Coloring Agents/chemistry , Plant Extracts/chemistry , Plant Leaves/chemistry , Green Chemistry Technology , Photolysis , Microscopy, Electron, Transmission
6.
Methods Cell Biol ; 187: 1-41, 2024.
Article in English | MEDLINE | ID: mdl-38705621

ABSTRACT

Correlative light and electron microscopy (CLEM) is an approach that combines the strength of multiple imaging techniques to obtain complementary information about a given specimen. The "toolbox" for CLEM is broad, making it sometimes difficult to choose an appropriate approach for a given biological question. In this chapter, we provide experimental details for three CLEM approaches that can help the interested reader in designing a personalized CLEM strategy for obtaining ultrastructural data by using transmission electron microscopy (TEM). First, we describe chemical fixation of cells grown on a solid support (broadest approach). Second, we apply high-pressure freezing/freeze substitution to describe cellular ultrastructure (cryo-immobilization approach). Third, we give a protocol for a ultrastructural labeling by immuno-electron microscopy (immuno-EM approach). In addition, we also describe how to overlay fluorescence and electron microscopy images, an approach that is applicable to each of the reported different CLEM strategies. Here we provide step-by step descriptions prior to discussing possible technical problems and variations of these three general schemes to suit different models or different biological questions. This chapter is written for electron microscopists that are new to CLEM and unsure how to begin. Therefore, our protocols are meant to provide basic information with further references that should help the reader get started with applying a tailored strategy for a specific CLEM experiment.


Subject(s)
Microscopy, Electron, Transmission , Humans , Microscopy, Electron, Transmission/methods , Animals , Cryoelectron Microscopy/methods , Microscopy, Electron/methods , Microscopy, Immunoelectron/methods , Microscopy, Fluorescence/methods , Freeze Substitution/methods
7.
Methods Cell Biol ; 187: 99-116, 2024.
Article in English | MEDLINE | ID: mdl-38705632

ABSTRACT

Correlative Light Electron Microscopy (CLEM) is a powerful technique to investigate the ultrastructure of specific cells and organelles at sub-cellular resolution. Transmission Electron Microscopy (TEM) is particularly useful to the field of virology, given the small size of the virion, which is below the limit of detection by light microscopy. Furthermore, viral infection results in the rearrangement of host organelles to form spatially defined compartments that facilitate the replication of viruses. With the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), there has been great interest to study the viral replication complex using CLEM. In this chapter we provide an exemplary workflow describing the safe preparation and processing of cells grown on coverslips and infected with SARS-CoV-2.


Subject(s)
COVID-19 , SARS-CoV-2 , SARS-CoV-2/ultrastructure , Humans , COVID-19/virology , Vero Cells , Chlorocebus aethiops , Animals , Microscopy, Electron, Transmission/methods , Virus Replication , Microscopy, Electron/methods
8.
Methods Cell Biol ; 187: 43-56, 2024.
Article in English | MEDLINE | ID: mdl-38705629

ABSTRACT

Correlative Light Electron Microscopy (CLEM) encompasses a wide range of experimental approaches with different degrees of complexity and technical challenges where the attributes of both light and electron microscopy are combined in a single experiment. Although the biological question always determines what technology is the most appropriate, we generally set out to apply the simplest workflow possible. For 2D cell cultures expressing fluorescently tagged molecules, we report on a simple and very powerful CLEM approach by using gridded finder imaging dishes. We first determine the gross localization of the fluorescence using light microscopy and subsequently we retrace the origin/localization of the fluorescence by projecting it onto the ultrastructural reference space obtained by transmission electron microscopy (TEM). Here we describe this workflow and highlight some basic principles of the sample preparation for such a simple CLEM experiment. We will specifically focus on the steps following the resin embedding for TEM and the introduction of the sample in the electron microscope.


Subject(s)
Workflow , Humans , Microscopy, Fluorescence/methods , Microscopy, Electron, Transmission/methods , Microscopy, Electron/methods , Animals
9.
Methods Mol Biol ; 2800: 89-102, 2024.
Article in English | MEDLINE | ID: mdl-38709480

ABSTRACT

In recent years, Correlative Multimodal Imaging (CMI) has become an "en vogue" technique and a bit of a buzzword. It entails combining information from different imaging modalities to extract more information from a sample that would otherwise not be possible from each individual technique. The best established CMI technology is correlative light and electron microscopy (CLEM), which applies light and electron microscopy on the exact same sample/structure. In general, it entails the detection of fluorescently tagged proteins or structures by light microscopy and subsequently their relative intracellular localization is determined with nanometer resolution using transmission electron microscopy (TEM). Here, we describe the different steps involved in a "simple" CLEM approach. We describe the overall workflow, instrumentation, and basic principles of sample preparation for a CLEM experiment exploiting stable expression of fluorescent proteins.


Subject(s)
Microscopy, Electron, Transmission , Humans , Microscopy, Electron, Transmission/methods , Microscopy, Fluorescence/methods , Microscopy, Electron/methods , Image Processing, Computer-Assisted/methods , Animals
10.
PeerJ ; 12: e16708, 2024.
Article in English | MEDLINE | ID: mdl-38715984

ABSTRACT

The present work aimed at differentiating five Amaranthus species from Saudi Arabia according to their morphology and the ability in nanoparticle formulation. Biogenic silver nanoparticles (AgNPs) were synthesized from leaf extracts of the five Amaranthus species and characterized by different techniques. Fourier-transform infrared spectroscopy (FT-IR) was used to identify the phyto-constituents of Amaranthus species. The nanoparticles (NPs) were characterized by UV-visible spectroscopy, dynamic light scattering (DLS), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDX). The antibacterial activity of the synthesized NPs was tested against Staphylococcus aureus, E. coli, Klebsiella pneumoniae and Pseudomonas aeruginosa using the agar well diffusion method. Spherical NPs varying in size and functional groups from the five plant species were demonstrated by TEM, DLS and FTIR analysis, respectively. Variations in NPs characteristics could be related to the phytochemical composition of each Amaranthus species since they play a significant role in the reduction process. EDX confirmed the presence of Ag in plant fabricated AgNPs. Antibacterial activity varied among the species, possibly related to the NPs characteristics. Varied characteristics for the obtained AgNPs may reflect variations in the phytochemical composition type and concentration among Amaranthus species used for their fabrication.


Subject(s)
Amaranthus , Anti-Bacterial Agents , Metal Nanoparticles , Microbial Sensitivity Tests , Plant Extracts , Silver , Amaranthus/chemistry , Metal Nanoparticles/chemistry , Silver/pharmacology , Silver/chemistry , Plant Extracts/pharmacology , Plant Extracts/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Spectroscopy, Fourier Transform Infrared , Humans , Pseudomonas aeruginosa/drug effects , Plant Leaves/chemistry , Escherichia coli/drug effects , Staphylococcus aureus/drug effects , Microscopy, Electron, Transmission , Saudi Arabia , Bacteria/drug effects , Klebsiella pneumoniae/drug effects
11.
Methods Cell Biol ; 187: 117-137, 2024.
Article in English | MEDLINE | ID: mdl-38705622

ABSTRACT

Correlative microscopy is an important approach for bridging the resolution gap between fluorescence light and electron microscopy. Here, we describe a fast and simple method for correlative immunofluorescence and immunogold labeling on the same section to elucidate the localization of phosphorylated vimentin (P-Vim), a robust feature of pulmonary vascular remodeling in cells of human lung small arteries. The lung is a complex, soft and difficult tissue to prepare for transmission electron microscopy (TEM). Detailing the molecular composition of small pulmonary arteries (<500µm) would be of great significance for research and diagnostics. Using the classical methods of immunochemistry (either hydrophilic resin or thin cryosections), is difficult to locate small arteries for analysis by TEM. To address this problem and to observe the same structures by both light and electron microscopy, correlative microscopy is a reliable approach. Immunofluorescence enables us to know the distribution of P-Vim in cells but does not provide ultrastructural detail on its localization. Labeled structures selected by fluorescence microscope can be identified and further analyzed by TEM at high resolution. With our method, the morphology of the arteries is well preserved, enabling the localization of P-Vim inside pulmonary endothelial cells. By applying this approach, fluorescent signals can be directly correlated to the corresponding subcellular structures in areas of interest.


Subject(s)
Lung , Vimentin , Humans , Vimentin/metabolism , Phosphorylation , Lung/metabolism , Lung/ultrastructure , Microscopy, Fluorescence/methods , Pulmonary Artery/metabolism , Pulmonary Artery/cytology , Pulmonary Artery/ultrastructure , Fluorescent Antibody Technique/methods , Endothelial Cells/metabolism , Endothelial Cells/ultrastructure , Microscopy, Electron, Transmission/methods , Microscopy, Electron/methods
12.
Curr Protoc ; 4(5): e1045, 2024 May.
Article in English | MEDLINE | ID: mdl-38717451

ABSTRACT

The cell surface distribution patterns (clustering) of membrane proteins have been widely investigated in cell biology. Here we describe a novel transmission electron microscopic (TEM) protocol designed to improve the quality of information obtained about the protein distribution patterns detected. This novel method makes it possible to study the clustering of all transmembrane proteins on one half of the cytoplasmic membrane of a whole cell. To achieve better imaging, we combine various methods, including critical-point drying, fixation of gold beads with a carbon layer, and a newly developed chemical thinning method. In addition, in our image-processing algorithm, we implemented pair correlation and pair cross-correlation functions, providing more details and better quantitative accuracy in characterizing the size and numbers of possible protein clusters. © 2024 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Sample preparation and transmission electron micrography Alternate Protocol: Direct cell labeling for transmission electron micrography Basic Protocol 2: Analysis of TEM images to detect immunogold-labeled proteins.


Subject(s)
Cell Membrane , Membrane Proteins , Microscopy, Electron, Transmission , Microscopy, Electron, Transmission/methods , Membrane Proteins/metabolism , Membrane Proteins/ultrastructure , Cell Membrane/metabolism , Cell Membrane/ultrastructure , Image Processing, Computer-Assisted/methods , Humans , Algorithms
13.
BMC Oral Health ; 24(1): 551, 2024 May 11.
Article in English | MEDLINE | ID: mdl-38734599

ABSTRACT

BACKGROUND: Periodontal diseases may benefit more from topical treatments with nanoparticles rather than systemic treatments due to advantages such as higher stability and controlled release profile. This study investigated the preparation and characterization of thermosensitive gel formulations containing clindamycin-loaded niosomes and solid lipid nanoparticles (SLNs) loaded with fluconazole (FLZ), as well as their in vitro antibacterial and antifungal effects in the treatment of common microorganisms that cause periodontal diseases. METHODS: This study loaded niosomes and SLNs with clindamycin and FLZ, respectively, and assessed their loading efficiency, particle size, and zeta potential. The particles were characterized using a variety of methods such as differential scanning calorimetry (DSC), dynamic light scattering (DLS), and Transmission Electron Microscopy (TEM). Thermosensitive gels were formulated by combining these particles and their viscosity, gelation temperature, in-vitro release profile, as well as antibacterial and antifungal effects were evaluated. RESULTS: Both types of these nanoparticles were found to be spherical (TEM) with a mean particle size of 243.03 nm in niosomes and 171.97 nm in SLNs (DLS), and respective zeta potentials of -23.3 and -15. The loading rate was 98% in niosomes and 51% in SLNs. The release profiles of niosomal formulations were slower than those of the SLNs. Both formulations allowed the release of the drug by first-order kinetic. Additionally, the gel formulation presented a slower release of both drugs compared to niosomes and SLNs suspensions. CONCLUSION: Thermosensitive gels containing clindamycin-loaded niosomes and/or FLZ-SLNs were found to effectively fight the periodontitis-causing bacteria and fungi.


Subject(s)
Clindamycin , Fluconazole , Gels , Liposomes , Nanoparticles , Particle Size , Periodontal Diseases , Clindamycin/administration & dosage , Clindamycin/therapeutic use , Nanoparticles/chemistry , Fluconazole/administration & dosage , Fluconazole/pharmacology , Periodontal Diseases/drug therapy , Antifungal Agents/administration & dosage , Antifungal Agents/pharmacology , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/pharmacology , Microscopy, Electron, Transmission , Temperature , Calorimetry, Differential Scanning , Candida albicans/drug effects , Viscosity , Lipids/chemistry , Humans
14.
Methods Mol Biol ; 2775: 141-153, 2024.
Article in English | MEDLINE | ID: mdl-38758316

ABSTRACT

This chapter describes methodological details for preparing specimens of Cryptococcus neoformans (although it can be applied to any species of the genus) and their subsequent analysis by scanning and transmission electron microscopy. Adaptations to conventional protocols for better preservation of the sample, as well as to avoid artifacts, are presented. The protocols may be used to examine both the surface ultrastructure and the interior of this pathogenic fungus in detail.


Subject(s)
Artifacts , Cryptococcus neoformans , Cryptococcus neoformans/ultrastructure , Microscopy, Electron, Transmission/methods , Microscopy, Electron, Scanning/methods , Specimen Handling/methods
15.
Invertebr Syst ; 382024 Feb.
Article in English | MEDLINE | ID: mdl-38744495

ABSTRACT

Ninetinae is a group of small to tiny short-legged spiders largely restricted to arid habitats. Among daddy-long-legs spiders (Pholcidae) this is by far the least diverse subfamily but this may partly be a result of inadequate collecting, poor representation in collections or scientific neglect. We build on a large recent collection of the ninetine genus Papiamenta Huber, 2000 from the Leeward Antilles and use cytochrome oxidase 1 (COI ) sequences, extensive scanning electron microscopy data, transmission electron microscopy data and karyotyping to analyse this geographically isolated and poorly known island genus. COI sequences support the split between the two morphologically distinct species on Curaçao but genetic distances between these are surprisingly low (7.4-9.8%; mean 8.6%). The type species P. levii (Gertsch, 1982) may include more than one species but COI and morphology suggest conflicting clade limits. A third species, P. bonay Huber sp. nov. is newly described from Bonaire. Our data on sperm ultrastructure and karyology are puzzling as these suggest different phylogenetic affinities of Papiamenta to other genera. Males transfer sperm as individual sperm (cleistosperm), agreeing with the putative closest relatives as suggested by molecular data, the North American genera Pholcophora and Tolteca . The sex chromosome system (X 1 X 2 X 3 Y ) of P. levii , however, is as in the South American Ninetinae genera Gertschiola and Nerudia but different from the putative closest relatives. ZooBank: urn:lsid:zoobank.org:pub:7A6A2E84-3A61-4637-AF6F-0E31A9FA79A8.


Subject(s)
Phylogeny , Spiders , Animals , Spiders/genetics , Spiders/classification , Male , Electron Transport Complex IV/genetics , Species Specificity , Female , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission
16.
Part Fibre Toxicol ; 21(1): 26, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38778339

ABSTRACT

BACKGROUND: During inhalation, airborne particles such as particulate matter ≤ 2.5 µm (PM2.5), can deposit and accumulate on the alveolar epithelial tissue. In vivo studies have shown that fractions of PM2.5 can cross the alveolar epithelium to blood circulation, reaching secondary organs beyond the lungs. However, approaches to quantify the translocation of particles across the alveolar epithelium in vivo and in vitro are still not well established. In this study, methods to assess the translocation of standard diesel exhaust particles (DEPs) across permeable polyethylene terephthalate (PET) inserts at 0.4, 1, and 3 µm pore sizes were first optimized with transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-VIS), and lock-in thermography (LIT), which were then applied to study the translocation of DEPs across human alveolar epithelial type II (A549) cells. A549 cells that grew on the membrane (pore size: 3 µm) in inserts were exposed to DEPs at different concentrations from 0 to 80 µg.mL- 1 ( 0 to 44 µg.cm- 2) for 24 h. After exposure, the basal fraction was collected and then analyzed by combining qualitative (TEM) and quantitative (UV-VIS and LIT) techniques to assess the translocated fraction of the DEPs across the alveolar epithelium in vitro. RESULTS: We could detect the translocated fraction of DEPs across the PET membranes with 3 µm pore sizes and without cells by TEM analysis, and determine the percentage of translocation at approximatively 37% by UV-VIS (LOD: 1.92 µg.mL- 1) and 75% by LIT (LOD: 0.20 µg.cm- 2). In the presence of cells, the percentage of DEPs translocation across the alveolar tissue was determined around 1% at 20 and 40 µg.mL- 1 (11 and 22 µg.cm- 2), and no particles were detected at higher and lower concentrations. Interestingly, simultaneous exposure of A549 cells to DEPs and EDTA can increase the translocation of DEPs in the basal fraction. CONCLUSION: We propose a combination of analytical techniques to assess the translocation of DEPs across lung tissues. Our results reveal a low percentage of translocation of DEPs across alveolar epithelial tissue in vitro and they correspond to in vivo findings. The combination approach can be applied to any traffic-generated particles, thus enabling us to understand their involvement in public health.


Subject(s)
Particulate Matter , Pulmonary Alveoli , Vehicle Emissions , Humans , Vehicle Emissions/toxicity , Vehicle Emissions/analysis , A549 Cells , Particulate Matter/toxicity , Particulate Matter/analysis , Pulmonary Alveoli/drug effects , Pulmonary Alveoli/metabolism , Particle Size , Microscopy, Electron, Transmission , Polyethylene Terephthalates/chemistry , Polyethylene Terephthalates/toxicity , Alveolar Epithelial Cells/drug effects , Alveolar Epithelial Cells/metabolism , Air Pollutants/toxicity , Air Pollutants/analysis
17.
Arthritis Res Ther ; 26(1): 102, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38778407

ABSTRACT

BACKGROUND: To perform a detailed morphological analysis of the inorganic portion of two different clinical presentations of calcium-based deposits retrieved from subjects with SSc and identify a chemical dissolution of these deposits suitable for clinical use. METHODS: Chemical analysis using Fourier Transform IR spectroscopy ('FTIR'), Raman microscopy, Powder X-Ray Diffraction ('PXRD'), and Transmission Electron Microscopy ('TEM') was undertaken of two distinct types of calcinosis deposits: paste and stone. Calcinosis sample titration with ethylenediaminetetraacetic acid ('EDTA') assessed the concentration at which the EDTA dissolved the calcinosis deposits in vitro. RESULTS: FTIR spectra of the samples displayed peaks characteristic of hydroxyapatite, where signals attributable to the phosphate and carbonate ions were all identified. Polymorph characterization using Raman spectra were identical to a hydroxyapatite reference while the PXRD and electron diffraction patterns conclusively identified the mineral present as hydroxyapatite. TEM analysis showed differences of morphology between the samples. Rounded particles from stone samples were up to a few micron in size, while needle-like crystals from paste samples reached up to 0.5 µm in length. Calcium phosphate deposits were effectively dissolved with 3% aqueous solutions of EDTA, in vitro. Complete dissolution of both types of deposit was achieved in approximately 30 min using a molar ratio of EDTA/HAp of ≈ 300. CONCLUSIONS: Stone and paste calcium-based deposits both comprise hydroxyapatite, but the constituent crystals vary in size and morphology. Hydroxyapatite is the only crystalline polymorph present in the SSc-related calcinosis deposits. Hydroxyapatite can be dissolved in vitro using a dosage of EDTA considered safe for clinical application. Further research is required to establish the optimal medium to develop the medical product, determine the protocol for clinical application, and to assess the effectiveness of EDTA for local treatment of dystrophic calcinosis.


Subject(s)
Calcinosis , Edetic Acid , Edetic Acid/chemistry , Humans , Calcinosis/drug therapy , Calcinosis/pathology , Spectroscopy, Fourier Transform Infrared/methods , Microscopy, Electron, Transmission/methods , X-Ray Diffraction/methods , Spectrum Analysis, Raman/methods , Female , Durapatite/chemistry , Middle Aged , Male , Calcium Chelating Agents/chemistry
18.
J Vis Exp ; (207)2024 May 03.
Article in English | MEDLINE | ID: mdl-38767370

ABSTRACT

Preclinical gene therapy research, particularly in rodent and large animal models, necessitates the production of AAV vectors with high yield and purity. Traditional approaches in research laboratories often involve extensive use of cell culture dishes to cultivate HEK293T cells, a process that can be both laborious and problematic. Here, a unique in-house method is presented, which simplifies this process with a specific cell factory (or cell stacks, CF10) platform. An integration of polyethylene glycol/aqueous two-phase partitioning with iodixanol gradient ultracentrifugation improves both the yield and purity of the generated AAV vectors. The purity of the AAV vectors is verified through SDS-PAGE and silver staining, while the ratio of full to empty particles is determined using transmission electron microscopy (TEM). This approach offers an efficient cell factory platform for the production of AAV vectors at high yields, coupled with an improved purification method to meet the quality demands for in vivo studies.


Subject(s)
Dependovirus , Genetic Vectors , Dependovirus/genetics , Humans , Genetic Vectors/chemistry , HEK293 Cells , Triiodobenzoic Acids/chemistry , Polyethylene Glycols/chemistry , Microscopy, Electron, Transmission
19.
Mikrochim Acta ; 191(6): 326, 2024 05 13.
Article in English | MEDLINE | ID: mdl-38740583

ABSTRACT

Migration is an initial step in tumor expansion and metastasis; suppressing cellular migration is beneficial to cancer therapy. Herein, we designed a novel biogated nanoagents that integrated the migration inhibitory factor into the mesoporous silica nanoparticle (MSN) drug delivery nanosystem to realize cell migratory inhibition and synergistic treatment. Antisense oligonucleotides (Anti) of microRNA-330-3p, which is positively related with cancer cell proliferation, migration, invasion, and angiogenesis, not only acted as the locker for blocking drugs but also acted as the inhibitory factor for suppressing migration via gene therapy. Synergistic with gene therapy, the biogated nanoagents (termed as MSNs-Gef-Anti) could achieve on-demand drug release based on the intracellular stimulus-recognition and effectively kill tumor cells. Experimental results synchronously demonstrated that the migration suppression ability of MSNs-Gef-Anti nanoagents (nearly 30%) significantly contributed to cancer therapy, and the lethality rate of the non-small-cell lung cancer was up to 70%. This strategy opens avenues for realizing efficacious cancer therapy and should provide an innovative way for pursuing the rational design of advanced nano-therapeutic platforms with the combination of cancer cell migratory inhibition.


Subject(s)
Cell Movement , Drug Therapy, Combination , Nanoparticles , Neoplasms , Silicon Dioxide , Cell Movement/drug effects , Silicon Dioxide/chemistry , Drug Therapy, Combination/methods , Neoplasms/drug therapy , Nanoparticle Drug Delivery System/chemistry , Nanoparticle Drug Delivery System/therapeutic use , Nanoparticles/chemistry , Nanoparticles/therapeutic use , Nanoparticles/ultrastructure , A549 Cells , Microscopy, Electron, Transmission , Humans
20.
J Helminthol ; 98: e40, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38738533

ABSTRACT

In the past decade, interest has significantly increased regarding the medicinal and nutritional benefits of pomegranate (Punica granatum) peel. This study examined the effects of using pomegranate peel extract (PGE) alone and in combination with albendazole (ABZ) on ultrastructural and immunological changes in cystic echinococcosis in laboratory-infected mice. Results revealed that the smallest hydatid cyst size and weight (0.48 ± 0.47mm, 0.17 ± 0.18 gm) with the highest drug efficacy (56.2%) was detected in the PGE + ABZ group, which also exhibited marked histopathological improvement. Ultrastructural changes recorded by transmission electron microscopy including fragmentation of the nucleus, glycogen depletion, and multiple lysosomes in vacuolated cytoplasm were more often observed in PGE + ABZ group. IFN-γ levels were significantly increased in the group treated with ABZ, with a notable reduction following PGE treatment, whether administered alone or in combination with ABZ. Thus, PGE enhanced the therapeutic efficiency of ABZ, with improvement in histopathological and ultrastructural changes.


Subject(s)
Albendazole , Echinococcosis , Plant Extracts , Pomegranate , Animals , Plant Extracts/pharmacology , Plant Extracts/administration & dosage , Pomegranate/chemistry , Mice , Echinococcosis/drug therapy , Echinococcosis/parasitology , Albendazole/pharmacology , Albendazole/administration & dosage , Anthelmintics/pharmacology , Anthelmintics/administration & dosage , Disease Models, Animal , Microscopy, Electron, Transmission , Interferon-gamma/blood , Female , Male
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