scanning electron microscopy (SEM) remains distinct in its ability to allow topographical visualization of structures. Key elements to consider for successful examination of biological specimens include appropriate pr...
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scanning electron microscopy (SEM) remains distinct in its ability to allow topographical visualization of structures. Key elements to consider for successful examination of biological specimens include appropriate preparative and imaging techniques. Chemical processing induces structural artifacts during specimen preparation, and several factors need to be considered when selecting fixation protocols to reduce these effects while retaining structures of interest. Particular care for proper dehydration of specimens is essential to minimize shrinkage and is necessary for placement under the high-vacuum environment required for routine operation of standard SEMs. Choice of substrate for mounting and coating specimens can reduce artifacts known as charging, and a basic understanding of microscope settings can optimize parameters to achieve desired results. This article describes fundamental techniques and tips for routine specimen preparation for a variety of biological specimens, preservation of labile or fragile structures, immune-labeling strategies, and microscope imaging parameters for optimal examination by SEM. (c) 2024 The Authors. Current Protocols published by Wiley Periodicals *** Protocol 1: Chemical preparative techniques for preservation of biological specimens for examination by SEMAlternate Protocol 1: Practical considerations for the preparation of soft tissuesAlternate Protocol 2: Removal of debris from the exoskeleton of invertebratesAlternate Protocol 3: Fixation of colonies grown on agar platesAlternate Protocol 4: Stabilization of polysaccharide structures with alcian blue and lysineAlternate Protocol 5: Preparation of non-adherent particulates in solution for SEMSupport Protocol 1: Application of thin layer of adhesive on substrate to improve adherenceSupport Protocol 2: Poly-L-lysine coating specimen substrates for improved adherenceSupport Protocol 3: Microwave processing of biological specimens for examination by SEMBasic Protocol 2: Cri
The objective of this novel research was to further understand the type, size and areal distribution of the non-metallic inclusions in bearing steels by applying state-of-the-art scanning electron microscopy (SEM) ana...
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The objective of this novel research was to further understand the type, size and areal distribution of the non-metallic inclusions in bearing steels by applying state-of-the-art scanning electron microscopy (SEM) analysis in order to develop steels with superior properties. Ten samples were taken from bearing steel grade 52100 and analysed by SEM. It was concluded that SEM allows deeper understanding regarding the type, morphology, size, and distribution of the non-metallic inclusions by covering larger sample areas and accurate automatic energy dispersive X-ray microanalysis of the inclusions. While most of the non-metallic inclusions had an equivalent circle diameter (ECD) smaller than 20 mu m, the main type of inclusions with ECDs larger than 20 mu m were calcium aluminates. As the higher sulphur will tend to create sulphide type of inclusions and the lower sulphur will shift the inclusions towards calcium aluminate oxide types, it is recommended to keep the sulphur content at amounts above threshold that calcium aluminates appear.
Among the 10 native cats of Iran, the Felis chaus is considered as one of the largely unknown species. Despite the reports on jungle cats in southeast Iran, there is no comprehensive information about their parasitic ...
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Among the 10 native cats of Iran, the Felis chaus is considered as one of the largely unknown species. Despite the reports on jungle cats in southeast Iran, there is no comprehensive information about their parasitic diseases. scanningelectron microscope (SEM) provides a valuable tool for the study of these organisms. In October 2022, a 15-year-old male jungle cat (F. chaus) was examined for gastrointestinal parasites using SEM which revealed exact parasite structures such as the mouth, shape of the lips, teeth and their position, papillae, excretory pore, and amphids. SEM of the Taenia taeniaeformis found in the F. chaus intestinal epithelium revealed that this tapeworm consisted of four unarmed suckers and a large armed rostellum. The rostellum was observed bearing double rings of alternating and circular hook arrangements. There were 21 large hooks in the anterior ring and 21 slightly smaller hooks in the posterior one. This study is the first report of Joyeuxiella echinorhyncoides from a jungle cat (F. chaus) in southeastern Iran. The rostellum was cylindrical and armed with thorn shape hooks that covered the whole rostellum with similar density. It was armed with 20-30 long hooks arranged in 16 rows. Four big suckers were visible at the base of the rostellum, two on each side. The suckers were round, and unlike the rostellum, these structures were unarmed. The results of the present study observed under SEM, indicated that organs such as sucker and rostellum in cestodes and mouth and the shape of lips and teeth in nematodes played a significant role in the biology of these helminths. The SEM reveals the surface structures and their relationships which results in better distinguishing the species and showing their detailed differences. More SEM studies need to be conducted on other species of cestodes and nematodes, along with pathological tests, to obtain more comprehensive and precise information about how these parasites harm this jungle cat host. The result
Introduction: Mesenchymal stem cells (MSCs) are increasingly used for intra-articular injections in the treatment of knee osteoarthritis. The aim of this study was to use scanning electron microscopy (SEM) to compare ...
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Introduction: Mesenchymal stem cells (MSCs) are increasingly used for intra-articular injections in the treatment of knee osteoarthritis. The aim of this study was to use scanning electron microscopy (SEM) to compare the morphological characteristics of synovial and adipose MSCs. Methods: Synovium and adipose tissues were concurrently harvested from eight patients with knee osteoarthritis. Suspensions of both synovial and adipose MSCs were examined to identify the presence of microspikes. In addition to this study, the MSC suspensions in four patients were applied to abraded porcine cartilage discs and observed 10 s, 10 min, and 1 h later. Results: The median percentage of cells exhibiting microspikes was 14% for synovial MSC suspensions and 13% for adipose MSC suspensions;this difference was not statistically significant (n = 8). No notable differences were detected in the number of adherent cells or in the proportion of cells displaying microspikes or pseudopodia. Strong correlations were found between the proportion of cells with pseudopodia and the number of attached cells for both synovial (r = 0.92, n = 12) and adipose (r = 0.86, n = 12) MSCs, with no significant difference in the correlation coefficients between the two groups. Conclusion: SEM analysis revealed no obvious differences in morphological characteristics during MSC adhesion to cartilage for either synovial or adipose MSCs. (c) 2024, The Japanese Society for Regenerative Medicine. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://***/licenses/by-nc-nd/ 4.0/).
Functional foods are not a brand novel idea. In the far east which is influenced by the Chinese culture, food and drugs were seen to have been composed of the same material. Traditional foods in Korea, Japan, China an...
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Functional foods are not a brand novel idea. In the far east which is influenced by the Chinese culture, food and drugs were seen to have been composed of the same material. Traditional foods in Korea, Japan, China and Ghana are now known as health foods based on the definition of a functional food. Many of them contain a variety of functional components which includes resistant starch, oligosaccharides, sugar alcohols, peptides and proteins. Diet, exercise and genetic factors are the most significant factors that contribute to health, according to a consumer study. The industry has studied diet and food technology to satisfy the needs of customers. Government was worried about the ageing of the country's population and the consequent health care costs in Japan, the longest life span in the world hence the endorsement and publicity of functional foods. This paper examines first the definitions of functional foods used at different locations. It also explores how electronmicroscopy has been used to determine the mechanism of action on of certain food products. We have said that 'functional foods can be interpreted in many ways and it is confusing because all foods are not functional after all The word "functional food" was introduced first in the studies of the Japanese Ministry of Education, Science and Culture in 1984. In 1988, in order to recommend methods of regulating these foods, the Japan Ministry of Health and Welfare organized a meeting for Functional Foods. In 1995, the ILSI organized Istanbul's First International Conference on Functional Food.
Human islet primary cilia are vital glucose-regulating organelles whose structure remains uncharacterized. scanning electron microscopy (SEM) is a useful technique for studying the surface morphology of membrane proje...
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Human islet primary cilia are vital glucose-regulating organelles whose structure remains uncharacterized. scanning electron microscopy (SEM) is a useful technique for studying the surface morphology of membrane projections like cilia, but conventional sample preparation does not reveal the submembrane axonemal structure, which holds key implications for ciliary function. To overcome this challenge, we combined SEM with membrane-extraction techniques to examine primary cilia in native human islets. Our data show well-preserved cilia subdomains which demonstrate both expected and unexpected ultrastructural motifs. Morphometric features were quantified when possible, including axonemal length and diameter, microtubule conformations, and chirality. We further describe a ciliary ring, a structure that may be a specialization in human islets. Key findings are correlated with fluorescence microscopy and interpreted in the context of cilia function as a cellular sensor and communications locus in pancreatic islets.
BackgroundThe extracellular matrix (ECM) structural deficiencies in chronic wounds prevent the wounds from healing through natural physiological processes. Electrospun biocompatible polymers offer a platform to produc...
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BackgroundThe extracellular matrix (ECM) structural deficiencies in chronic wounds prevent the wounds from healing through natural physiological processes. Electrospun biocompatible polymers offer a platform to produce microstructure wound dressing materials that mimic the ECM containing various bioactives to address the deficiencies in the chronic wound healing process. Quantitative characterization of the electrospun fiber microstructure could provide valuable information on using fiber constructs to facilitate wound healing. This work employed a validated image analysis tool to quantitatively explain various parameters for the microstructure of six electrospun fiber constructs, D1{Polycaprolactone (PCL), Polyvinyl alcohol (PVA), Keratin}, D2{PCL, PVA, keratin, Co-enzyme Q10 (CoQ10)}, D3 (PCL, PVA, keratin, mupirocin), D4 (PCL, PVA, keratin, CoQ10, mupirocin, valsartan), D5 {PVA, Hyaluronic acid (HA)}, and D6 (PVA), using scanning electron microscopy imaging *** fiber intersection density (FID) parameter was quantified in the formulations, e.g., 0.272% for D5 and 0.416% for D4. Orientation histograms for D1 and D6 are characteristic of isotropic materials, while orientations for D2 and D3 indicate anisotropy with 2 preferred orientations in each formulation. D4 and D5 present orientations characteristic of transversely isotropic materials. The tortuosity for D2 and D4 indicates almost straight fiber segments, in contrast with undulated fiber segments in all other formulations. Furthermore, the mean fiber diameter was quantified, e.g., 1.414 and 1.630 mm for D3 and D4, ***-electrospun PVA/PCL microfibers offer great potential for controlled delivery of bioactives needed to accelerate the healing of chronic wounds. This image-based analysis technology quantitatively characterized different formulations of electrospun fiber scaffolds. This analysis sets the stage for future study that utilizes microstructural information in finit
A novel method for characterizing the diameter of inner conductors in high-frequency coaxial air lines is presented. It is based on scanning electron microscopy and can be seen as a complement to the use of laser micr...
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ISBN:
(纸本)9798350365948;9798350365931
A novel method for characterizing the diameter of inner conductors in high-frequency coaxial air lines is presented. It is based on scanning electron microscopy and can be seen as a complement to the use of laser micrometers, offering its own distinct advantages. The proposed method was implemented and tested in an international comparison as part of an EMPIR project.
electronmicroscopy of biological materials such as bacteria allows multifaceted analysis to understand their structure and function with high resolution, which is difficult to achieve with optical microscopy. However...
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electronmicroscopy of biological materials such as bacteria allows multifaceted analysis to understand their structure and function with high resolution, which is difficult to achieve with optical microscopy. However, the samples are damaged or broken by electron beam irradiation and by the vacuum environment. Here, we observed bacteria in a suspension encapsulated in a graphene sandwich that prevents electron beam damage without the need for fixation. Specifically, we demonstrated in situ scanning electron microscopy observation of Escherichia coli in a graphene sandwich containing a perforated membrane as a spacer, encapsulating non-immobilized E. coli between the graphene layers. However, E. coli activity, such as division, was not observed, although the irradiated cells grew slightly when resuspended under optimal culture conditions. Our findings suggest that the graphene sandwich methodology enables the observation of wet E. coli cells by electronmicroscopy but requires refinement to allow the live imaging of biological materials.
A new visualization method of insulin amyloid fibril has been presented via conventional scanning electron microscopy (SEM), which can be applied to confirm the fibril formation and any effect of additives. We have de...
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A new visualization method of insulin amyloid fibril has been presented via conventional scanning electron microscopy (SEM), which can be applied to confirm the fibril formation and any effect of additives. We have demonstrated that native insulin amyloid fibrils can be imaged without any metal coating on the silicon substrate and were attributed to the attenuation effect upon the collected secondary electrons. The conventional SEM observations consistently showed distinct morphologies of the fibrils under the effects of three different molecules (citrulline, ectoin, and trehalose) and well coincident with atomic force microscopic (AFM) data. In spite of negative result for trehalose-treated samples with conventional thioflavin T (Th-T) assay, thin and long fibrils were thoroughly observed and it revealed a complementary capability of the present strategy. In addition, direct sampling of amyloid fibrils on silicon chips for SEM observations substantially expedites the sampling and searching efforts, thereby shedding a new light on inhibitor screening approach for diverse amyloid fibrillation.
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