Procedures for obtaining sectional views of fungal fructifications by scanning electron microscopy

1976 ◽  
Vol 22 (9) ◽  
pp. 1252-1257 ◽  
Author(s):  
M. F. Brown ◽  
H. G. Brotzman
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Periodic Acid ◽  
Ceratocystis Fimbriata ◽  
Internal Structures ◽  
Excellent Preservation ◽  
Coating Procedure ◽  
Lecanosticta Acicola ◽  
Host Tissues ◽  
Scanning Electron

Procedures for sectioning fungal fructifications in host tissues or on artificial media are described, which allow observation of internal structures by scanning electron microscopy. Perithecia of Ceratocystis fimbriata and Phyllachora graminis, and telia of Puccinia xanthii showed excellent preservation of exposed structures in sections which were osmium-coated before being dried. While similar preservation was obtained in sectioned acervuli of Lecanosticta acicola and Marssonina juglandis and in pycnidia of Dothiorella ribis and Phomopsis occulta, the mucilaginous substances produced in these fructifications precluded observation of conidiophores. Extraction of mucilage from these sections was accomplished by periodic acid and dilute KOH treatments, followed by an osmium-coating procedure. In such preparations, mucilage was removed, internal structures were preserved, and pertinent characteristics of conidiogenous cells were resolved.

scholarly journals Evaluation of ultrastructural alterations of glomerular basement membrane and podocytes in glomeruli by low-vacuum scanning electron microscopy

2021 ◽  
Author(s):  
Ping Lan ◽  
Dedong Kang ◽  
Akiko Mii ◽  
Yoko Endo ◽  
Masako Tagawa ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Basement Membrane ◽  
Glomerular Basement Membrane ◽  
Assessment Tool ◽  
Periodic Acid ◽  
Renal Pathology ◽  
Blue Staining ◽  
Formalin Fixed Paraffin Embedded ◽  
Scanning Electron

Abstract Background Low-vacuum scanning electron microscopy (LV-SEM) is applied to diagnostic renal pathology. Methods To demonstrate the usefulness of LV-SEM and to clarify the optimal conditions of pathology samples, we investigated the alterations of glomerular basement membrane (GBM) and podocytes in control and experimental active Heymann nephritis (AHN) rats by LV-SEM. Results On week 15 following induction of AHN, spike formation on GBM with diffuse deposition of IgG and C3 developed. Using LV-SEM, diffuse crater-like protrusions were clearly noted three-dimensionally (3D) on surface of GBM in the same specimens of light microscopy (LM) and immunofluorescence (IF) studies only after removal coverslips or further adding periodic acid-silver methenamine (PAM) staining. These 3D ultrastructural findings of GBM surface could be detected in PAM-stained specimens by LV-SEM, although true GBM surface findings could not be obtained in acellular glomeruli, because some subepithelial deposits remained on surface of GBM. Adequate thickness was 1.5–5 μm for 10% formalin-fixed paraffin-embedded (FFPE) and 5–10 μm for the unfixed frozen sections. The foot processes and their effacement of podocytes could be observed by LV-SEM using 10%FFPE specimens with platinum blue (Pt-blue) staining or double staining of PAM and Pt-blue. These findings were obtained more large areas in 2.5% glutaraldehyde-fixed paraffin-embedded (2.5%GFPE) specimens. Conclusion Our findings suggest that LV-SEM is a useful assessment tool for evaluating the alterations of GBM and podocytes in renal pathology using routine LM and IF specimens, as well as 2.5%GFPE specimens.

Scanning Electron Microscopy of Ethanol Infiltrated Freeze-Fractured Cell Pellets

1974 ◽  
Vol 32 ◽  
pp. 98-99
Author(s):  
William G. Henk ◽  
Ben O. Spurlock
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Critical Point ◽  
Freeze Drying ◽  
Cultured Cells ◽  
Resolving Power ◽  
Ice Crystal ◽  
Internal Structures ◽  
Critical Point Drying ◽  
Scanning Electron

The increased depth of focus and superior resolving power of the scanning electron microscope provide advantages over the light microscope in viewing the external morphology of cultured cells and protists. Internal structures have, however, proved more difficult to observe. Freeze drying adequately preserves surface structures but results in poorly preserved cytoplasmic elements due to ice crystal damage. Critical point drying results in good preservation of both surface and cytoplasmic fine structure. Attempts to cut or break critical point dried material, however, result in plastic deformation of the cells. Humphreys, et al, recently introduced freeze fracturing of ethanol infiltrated tissues for biological scanning electron microscopy. We have modified and applied their technique and obtained similar results with Paramecium sp. obtained from mass cultures.

Preparation of pycnidium-forming fungi for observation by scanning electron microscopy

1974 ◽  
Vol 52 (5) ◽  
pp. 1101-1105 ◽  
Author(s):  
R. J. Zeyen ◽  
B. L. Shearer
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
Uranyl Acetate ◽  
Air Drying ◽  
Phoma Medicaginis ◽  
Total Procedure ◽  
Host Tissues ◽  
Scanning Electron

A procedure for the preparation of pycnidium-forming fungi, inside host tissues, for observation by scanning electron microscopy (SEM) has been developed, and consists of removal of mucilage from the pycnidium followed by fixation, embedding, and precision sectioning of pycnidia before final SEM preparation. The fungus tissues were fixed in glutaraldehyde and uranyl acetate. Tissues were prevented from collapsing by using glycerol substitution followed by air drying. The total procedure allows for direct comparisons, using the same sections, for light microscopy and SEM. Six species from the order Sphaeropsidales (Septoria avenae, S. avenae f, sp. triticea, S. nodorum, S. tritici, Darluca filum, and Phoma medicaginis) were used as experimental organisms; although only two species, S. avenae and S. tritici are pictorially represented.

scholarly journals Microtomographic study on the anatomy of adult male eyes of two mayfly species

Zoosymposia ◽  
2016 ◽  
Vol 11 ◽  
pp. 101-120 ◽  
Author(s):  
JAVIER ALBA-TERCEDOR
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Resolution ◽  
Adult Male ◽  
Transfer Functions ◽  
X Ray ◽  
Internal Structures ◽  
Evolutionary Advantage ◽  
Non Destructive ◽  
Scanning Electron

Here I present the results obtained by scanning male adults of two mayfly (Ephemeroptera) species with a high resolution micro-tomographic scanner, allowing observation of external structures, with similar results to those obtained under scanning electron microscopy. Moreover, this non-destructive technique permits investigation of the internal structures, and to “navigate” inside them, in a way never before imagined. Moreover by using different transfer functions and in accordance with the X-ray transparency, it is possible to assign different colours to highlight different anatomical parts, and to obtain “aesthetic” images. Results are compared and discussed with previous findings. It is postulated that differences in the diameter sizes of the ommatidia, when comparing dorso-frontal and ventro-lateral parts of the compounds eyes, represent an evolutionary advantage enabling increased accuracy in movement displacement detection of competing males within the swarm.

Preparation of dipteran larvae for scanning electron microscopy using a freeze-substitution technique

1986 ◽  
Vol 64 (3) ◽  
pp. 797-799 ◽  
Author(s):  
Douglas D. Colwell ◽  
Eric G. Kokko
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Freeze Substitution ◽  
Rapid Freezing ◽  
Fixation Methods ◽  
Good Preservation ◽  
Larval Stages ◽  
Excellent Preservation ◽  
Standard Fixation ◽  
Scanning Electron

Difficulties are often encountered in achieving good preservation of dipteran larvae for scanning electron microscopy. Standard fixation methods frequently fail because fixatives do not penetrate the cuticle rapidly, resulting in distortion and generation of artifacts on the surface. A freeze-substitution technique that produces excellent preservation of the larval stages of a wide variety of Diptera is described. The method employs Freon 12 for rapid freezing of the specimens and methanol as the substitution fluid. The technique is simple, inexpensive, and demonstrates a significant improvement in preservation of specimens.

scholarly journals Resistance in Mango Against Infection by Ceratocystis fimbriata

2014 ◽  
Vol 104 (8) ◽  
pp. 820-833 ◽  
Author(s):  
Leonardo Araujo ◽  
Wilka Messner Silva Bispo ◽  
Isaías Severino Cacique ◽  
Wiler Ribas Moreira ◽  
Fabrício Ávila Rodrigues
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Ultrastructural Level ◽  
Stem Tissue ◽  
Ceratocystis Fimbriata ◽  
X Ray ◽  
Cell Responses ◽  
Mango Wilt ◽  
Fluorescence Light ◽  
Scanning Electron

This study was designed to characterize and describe host cell responses of stem tissue to mango wilt disease caused by the fungus Ceratocystis fimbriata in Brazil. Disease progress was followed, through time, in inoculated stems for two cultivars, ‘Ubá’ (field resistant) and ‘Haden’ (field susceptible). Stem sections from inoculated areas were examined using fluorescence light microscopy and transmission and scanning electron microscopy, coupled with energy-dispersive X-ray microanalysis. Tissues from Ubá colonized by C. fimbriata had stronger autofluorescence than those from Haden. The X-ray microanalysis revealed that the tissues of Ubá had higher levels of insoluble sulfur and calcium than those of Haden. Scanning electron microscopy revealed that fungal hyphae, chlamydospores (aleurioconidia), and perithecia-like structures of C. fimbriata were more abundant in Haden relative to Ubá. At the ultrastructural level, pathogen hyphae had grown into the degraded walls of parenchyma, fiber cells, and xylem vessels in the tissue of Haden. However, in Ubá, plant cell walls were rarely degraded and hyphae were often surrounded by dense, amorphous granular materials and hyphae appeared to have died. Taken together, the results of this study characterize the susceptible and resistant basal cell responses of mango stem tissue to infection by C. fimbriata.

scholarly journals Pathological Analysis of Early Transplant Glomerulopathy in Renal Allografts Using Low-Vacuum Scanning Electron Microscopy

Nephron ◽  
2020 ◽  
pp. 1-8
Author(s):  
Hiroka Onishi ◽  
Hideyo Oguchi ◽  
Kazunobu Shinoda ◽  
Tetuo Mikami ◽  
Taichi Arai ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Capillary Number ◽  
Periodic Acid ◽  
Kidney Transplant Recipients ◽  
Average Percentage ◽  
Antibody Mediated Rejection ◽  
Biopsy Specimens ◽  
Transplant Glomerulopathy ◽  
Scanning Electron

<b><i>Aim:</i></b> Low-vacuum scanning electron microscopy (LVSEM) has been reported to aid in diagnosis of renal biopsy. This study evaluated early transplant glomerulopathy in kidney transplant recipients using LVSEM. <b><i>Methods:</i></b> We selected 4 biopsies of cg0, 5 biopsies of cg1a, 5 biopsies of cg1b, and 4 biopsies of cg2 lesions that had been evaluated by light microscopy (LM) and transmission electron microscopy from recipients with acute/active or chronic, active antibody-mediated rejection (AABMR or CAABMR). Renal allograft paraffin sections (1 µm thickness) were stained with periodic acid-methenamine silver and observed using LVSEM. The cg score was based on the Banff classification. The parameter “percentage of duplicated capillary number” was calculated as follows: in 1 glomerulus with glomerular basement membrane (GBM) duplication, the total duplicated capillary number/the total number of capillaries ×100. <b><i>Results:</i></b> In all 4 biopsy specimens with AABMR showing cg0, LVSEM revealed GBM duplication not identified by LM. The average percentage of duplicated capillary number per glomerulus with GBM duplication was higher when observed by LVSEM than when observed by LM in all cg1b and cg2 biopsy specimens. <b><i>Conclusion:</i></b> LVSEM revealed early GBM duplication in AABMR. Early GBM duplication might progress in the very early phase of AABMR. GBM duplication was more frequently detected by LVSEM than by LM in biopsy specimens with early chronic, active antibody mediated rejection. Thus, LVSEM may be useful in diagnosis of early transplant glomerulopathy.

scholarly journals Differentiating Trypanosoma cruzi in a Host Mammalian Cell Imaged in Aqueous Liquid by Atmospheric Scanning Electron Microscopy

2022 ◽  
Author(s):  
Yuko Takagi ◽  
Mari Sato ◽  
Masami Naya ◽  
Chikara Sato
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Trypanosoma Cruzi ◽  
Mammalian Cell ◽  
Cell Plasma Membrane ◽  
Content Type ◽  
Cell Plasma ◽  
Internal Structures ◽  
Infectious Stage ◽  
Scanning Electron

Using Atmospheric Scanning Electron Microscopy (ASEM), we visualized interaction between infectious stage of Trypanosoma cruzi and completely intact host mammalian cell. Plasma membrane appears translucent under ASEM, which not only enables direct observation of T. cruzi within its host cell, but also reveals internal structures of the parasite itself.

A comparison of external and internal maxilla and mandible morphology of water bugs (Hemiptera: Heteroptera: Nepomorpha)

Zootaxa ◽  
2013 ◽  
Vol 3635 (4) ◽  
pp. 340-378 ◽  
Author(s):  
JOLANTA BROŻEK
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Ground Plan ◽  
Internal Structures ◽  
Maxilla And Mandible ◽  
Future Work ◽  
Morphological Ground ◽  
Water Bugs ◽  
Scanning Electron

This paper describes the file of the mandible, the apices of the maxillae, the rupturing device on the maxillae, and the internal structures of the mouthparts in sixty representatives of the nepomorphan families (Heteroptera), using scanning electron microscopy. Eight morphologically distinct types of files are identified on the mandibular tip, as well as six distinct types of the maxillary endings, and three distinct types of rupturing devices of the maxillae. The features of the internal maxillary and mandibular structures share a common connection model, differing only by virtue of specific appendages in different subfamilies. The water bugs morphological ground plan is represented by a mandibular file identically serrated, asymmetrical apices of maxillae (left maxilla tapers with lobe + right maxilla tapers and straight), rupturing device evidently exposed ventrally and inner structures: the maxillae are extended dorso-laterally, forming a wide lobe; symmetrical processes connect with the mandibles. The main patterns (belostomatid and nepid) together with two more specialized patterns (gelastocorids, corixids, micronectids, and diaprepocorids) and (ochterid, aphelocheirid, naucorid, notonectid, pleid and helotrephid) are reported. Diversity of the elements (maxillae and mandibles) are analyzed from a phylogenetic signals and nutrition perspective. Finally, further lines of study are suggested for future work on the phylogeny of the group based on the studied characters.

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