Ultrastructural Dendritic Changes Underlying Diaschisis After Capsular Infarct

Abstract Diaschisis has been described as functional depression distant to the lesion. A variety of neuroscientific approaches have been used to investigate the mechanisms underlying diaschisis. However, few studies have examined the pathological changes in diaschisis at ultrastructural level. Here, we used a rat model of capsular infarct that consistently produces diaschisis in ipsilesional and contralesional motor and sensory cortices. To verify the occurrence of diaschisis and monitor time-dependent changes in diaschisis, we performed longitudinal 2-deoxy-2-[18F]-fluoro-d-glucose microPET (FDG-microPET) study. We also used light and electron microscopy to identify the microscopic and ultrastructural changes at the diaschisis site at 7, 14, and 21 days after capsular infarct modeling (CIM). FDG-microPET showed the occurrence of diaschisis after CIM. Light microscopic examinations revealed no significant histopathological changes at the diaschisis site except a mild degree of reactive astrogliosis. However, electron microscopy revealed swollen, hydropic degeneration of axial dendrites and axodendritic synapses, although the neuronal soma (including nuclear chromatin and cytoplasmic organelles) and myelinated axons were relatively well preserved up to 21 days after injury. Furthermore, number of axodendritic synapses was significantly decreased after CIM. These data indicate that a circumscribed subcortical white-matter lesion produces ultrastructural pathological changes related to the pathogenesis of diaschisis.

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Ultrastructural Changes of the Tracheal Epithelium after Vaccination of Day-Old Chickens with the La Sota Strain of Newcastle Disease Virus

Veterinary Pathology ◽

10.1354/vp.42-5-559 ◽

2005 ◽

Vol 42 (5) ◽

pp. 559-565 ◽

Cited By ~ 37

Author(s):

J. Mast ◽

C. Nanbru ◽

T. van den Berg ◽

G. Meulemans

Keyword(s):

Electron Microscopy ◽

Newcastle Disease Virus ◽

Disease Virus ◽

Newcastle Disease ◽

Goblet Cells ◽

Ultrastructural Level ◽

Ultrastructural Changes ◽

Ciliated Cells ◽

Specific Pathogen ◽

And Function

The progression of tracheal lesions induced by vaccination of day-old specific pathogen-free chicks with the La Sota strain of Newcastle disease virus (NDV) was examined by relating surface changes as observed by scanning electron microscopy with subcellular changes seen by transmission electron microscopy. NDV infection resulted in hypertrophy of goblet cells, their rupture, and the formation of excess mucus. Activation of goblet cells peaked within 4 days postvaccination. Afterward, the activation levels gradually decreased. At the level of the ciliated cells, a marked increase in the proportion of nonciliated to ciliated cells and later an almost complete deciliation of the tracheal surface were observed because a simple squamous to cuboidal epithelium replaced the original pseudostratified epithelium. Fifteen days postvaccination, all epithelial damage was restored. Because the observed vaccination-induced lesions are detrimental to epithelial integrity and function as a barrier against invading microorganisms, they might explain at the ultrastructural level the secondary complications of vaccination with the La Sota strain against NDV

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Light and electron microscopy characteristics of the muscle of patients with SURF1 gene mutations associated with Leigh disease

Journal of Clinical Pathology ◽

10.1136/jcp.2007.051060 ◽

2007 ◽

Vol 61 (4) ◽

pp. 460-466 ◽

Cited By ~ 22

Author(s):

M Pronicki ◽

E Matyja ◽

D Piekutowska-Abramczuk ◽

T Szymańska-Dębińska ◽

A Karkucińska-Więckowska ◽

...

Keyword(s):

Electron Microscopy ◽

Lipid Accumulation ◽

Morphological Changes ◽

Light And Electron Microscopy ◽

Gene Mutations ◽

Leigh Syndrome ◽

Typical Feature ◽

Ultrastructural Changes ◽

Consistent Feature ◽

Muscle Changes

Aims:Leigh syndrome (LS) is characterised by almost identical brain changes despite considerable causal heterogeneity. SURF1 gene mutations are among the most frequent causes of LS. Although deficiency of cytochrome c oxidase (COX) is a typical feature of the muscle in SURF1-deficient LS, other abnormalities have been rarely described. The aim of the present work is to assess the skeletal muscle morphology coexisting with SURF1 mutations from our own research and in the literature.Methods:Muscle samples from 21 patients who fulfilled the criteria of LS and SURF1 mutations (14 homozygotes and 7 heterozygotes of c.841delCT) were examined by light and electron microscopy.Results:Diffuse decreased activity or total deficit of COX was revealed histochemically in all examined muscles. No ragged red fibres (RRFs) were seen. Lipid accumulation and fibre size variability were found in 14 and 9 specimens, respectively. Ultrastructural assessment showed several mitochondrial abnormalities, lipid deposits, myofibrillar disorganisation and other minor changes. In five cases no ultrastructural changes were found. Apart from slight correlation between lipid accumulation shown by histochemical and ultrastructural techniques, no other correlations were revealed between parameters investigated, especially between severity of morphological changes and the patient’s age at the biopsy.Conclusion:Histological and histochemical features of muscle of genetically homogenous SURF1-deficient LS were reproducible in detection of COX deficit. Minor muscle changes were not commonly present. Also, ultrastructural abnormalities were not a consistent feature. It should be emphasised that SURF1-deficient muscle assessed in the light and electron microscopy panel may be interpreted as normal if COX staining is not employed.

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Cytology and ultrastructure of Thanatephorus cucumeris and related taxa of the Rhizoctonia complex

Canadian Journal of Botany ◽

10.1139/b77-276 ◽

1977 ◽

Vol 55 (18) ◽

pp. 2419-2436 ◽

Cited By ~ 23

Author(s):

C. C. Tu ◽

James W. Kimbrough ◽

H. C. Aldrich

Keyword(s):

Electron Microscopy ◽

Light Microscope ◽

Light And Electron Microscopy ◽

Middle Layer ◽

Ultrastructural Level ◽

Aniline Blue ◽

Diploid Nucleus ◽

Thanatephorus Cucumeris ◽

Light Microscope Level ◽

Endoplasmic Reticula

Cytological studies on the vegetative hyphae of members of the Rhizoctonia complex and basidial structures of Thanatephorus cucumeris were performed with light and electron microscopy. Vegetative cells of Thanatephorus and Waitea proved to be multinucleate, whereas those of Uthatobasidium, Ceratobasidium, Athelia. and Botryobasidium are binucleate.Dolipore septa of Thanatephorus, Waitea, Uthatobasidium, and Ceratobasidium are visible with the light microscope when stained with aniline blue in glycerine. Ultrastructurally, pore caps in these genera consisted of two-layered unit membranes, forming cisternae with an electron-dense middle layer. Dolipore septa of Athelia (S. rolfsii) and Botryobasidium are not visible in aniline blue at the light microscope level. At the ultrastructural level, there was an additional cisternal membrane making up a pore cap of three membranes. The fine structure of nuclei, mitochondria, endoplasmic reticula, vacuoles, and other organelles in the basidial structures of T. cucumeris was essentially the same as in other basidiomycetes.Karyogamy of two haploid nuclei occurs in the young basidia of T. cucumeris. The nuclear envelopes of both haploid nuclei break at their adjacent sides and fuse to form a diploid nucleus. After a short interphase, meiosis occurs. No leptotene was observed at prophase I, but a synaptinemal complex was evident and six pairs of chromosomes were observed throughout pachytene, diplotene, and diakinesis. The nuclear envelope disappears at metaphase I and a spindle appears. The second meiotic division is equational. Most of the mature and discharged spores are uninucleate.

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Histopathological and Ultrastructural Changes in the Liver and Gills of the Killifish Aphanius Dispar (Cyprinodontidae) Exposed to Aflatoxin B1

Sultan Qaboos University Journal for Science [SQUJS] ◽

10.24200/squjs.vol20iss1pp1-10 ◽

2015 ◽

Vol 20 (1) ◽

pp. 1

Author(s):

Horiya H. Al-Azri ◽

Taher Ba-Omar ◽

Abdulkadir Elshafie ◽

Michael J Barry

Keyword(s):

Electron Microscopy ◽

Aflatoxin B1 ◽

Light And Electron Microscopy ◽

Ultrastructural Changes ◽

Unusual Behavior ◽

High Doses

Aflatoxin B1 (AFB1) is a mycotoxin which can cause serious toxicity to animals and humans. The aim of this study was to investigate the effects of AFB1 in Aphanius dispar fish and measure residues in tissues after in vivo exposure. Aphanius dispar were fed diets containing 50, 100, 150 and 200 µg AFB1/kg for 10, 20 and 30 days. At the end of the experiment, the liver and gills were dissected out and processed for light and electron microscopy. During the experiment, no external changes or unusual behavior were observed in the fish. Histopathological and ultrastructural changes in liver appeared under all four treatments: 50, 100, 150 and 200 µg AFB1/kg. Gill tissues were affected at high doses of 100,150 and 200 µg AFB1/kg. Accumulation of AFB1 residues in liver and gill tissues was found to be related to a dose and duration of exposure.

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Single Processing of Tissue for Light and Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100080183 ◽

1977 ◽

Vol 35 ◽

pp. 550-551 ◽

Cited By ~ 1

Author(s):

W. A. Burns ◽

A. M. Bretschneider ◽

A. B. Morrison

Keyword(s):

Electron Microscopy ◽

Light And Electron Microscopy ◽

Ultrastructural Level ◽

Significant Problem ◽

Diagnostic Ability ◽

Large Samples ◽

Microscopic Evaluation ◽

Light Microscopist ◽

Plastic Embedding ◽

Electron Microscopist

Tissues for light and electron microscopy are traditionally processed separately. Different fixatives and embedding media are usually employed. Paraffin is unsuitable for electron microscopy and the small amounts of tissue generally embedded in plastic makes sampling a significant problem for the light, as well as the electron microscopist. Techniques, however, have been described for plastic embedding of large samples of tissue which can be sectioned at 1 μm. The added resolution of these thinner sections potentially increases the diagnostic ability of the light microscopist. These techniques have not been fully utilized in pathology. If one fixative were utilized and the quantity embedded in plastic were comparable to that which is normally processed for paraffin, then the investigator could use plastic sections for better light microscopic evaluation with the option of subsequent examination of the same region in the same block at an ultrastructural level.

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Hepatic cytoprotection in treatment of canine heartworm

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100156572 ◽

1989 ◽

Vol 47 ◽

pp. 918-919

Author(s):

D.L. Friesen ◽

A. Singh ◽

M.E. Hitt

Keyword(s):

Electron Microscopy ◽

Phosphate Buffer ◽

Osmium Tetroxide ◽

Light And Electron Microscopy ◽

Ultrastructural Changes ◽

Sample Treatment ◽

Host Animal ◽

Thin Sections ◽

Canine Heartworm ◽

Toxic Metabolites

Thiacetarsamide is an arsenic-containing drug used in the treatment of heartworm in dogs. The effective antihelmintic dose is toxic to the host animal. Acetylcysteine decreases the hepatotoxicity of some compounds by forming a conjugate with toxic metabolites of the compound. The purpose of this study was to evaluate the effectiveness of a cytoprotectant for hepatocytes in dogs treated with therapeutic levels of thiacetarsamide.Eighteen dogs were divided randomly into two groups. All dogs were given four doses of thiacetarsamide over two days. Nine dogs were given 10% acetylcysteine 15 min prior to each dose of thiacetarsamide. Needle biopsies of the liver were taken from each dog prior to the treatment and again one week post-treatment. The biopsies were fixed in 2% gluraraldehyde in phosphate buffer, pH 7.3, post-fixed in 1% osmium tetroxide, and processed for electron microscopy. Semithin and thin sections of the liver were examined by light and electron microscopy, respectively, for histopathologic and ultrastructural changes. The specimens were coded and the sample treatment was not known to the researchers at the time of observation.

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Efficient fluorescence recovery using antifade reagents in correlative light and electron microscopy

Microscopy ◽

10.1093/jmicro/dfz029 ◽

2019 ◽

Vol 68 (5) ◽

pp. 417-421

Author(s):

Kiminori Toyooka ◽

Naeko Shinozaki-Narikawa

Keyword(s):

Electron Microscopy ◽

Fluorescent Protein ◽

Light And Electron Microscopy ◽

Ultrastructural Level ◽

Fluorescence Decay ◽

Fluorescence Recovery ◽

Recovery Method ◽

Thin Sections ◽

Electron Microscopies ◽

Green Fluorescent

Abstract Correlative light and electron microscopy (CLEM) enables ultrastructural-level analysis of fluorescence-labeled proteins by combining images obtained from both fluorescence and electron microscopies. A technical challenge with the CLEM method is the effective detection of fluorescence from samples embedded in resins, which generally cause fluorescence decay. To overcome this issue, we developed a method for fluorescence recovery of green fluorescent protein (GFP) in resin-embedded semi-thin sections using commercially available antifade reagents. By applying this method, we successfully obtained CLEM images using field-emission scanning electron microscopy with moderately enhanced GFP signals, demonstrating the efficacy of this simple fluorescence recovery method.

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Effects of castration on androgen receptors and gonadotropins in the pituitary of adult male viscachas

Reproduction Fertility and Development ◽

10.1071/rd13126 ◽

2014 ◽

Vol 26 (7) ◽

pp. 991 ◽

Cited By ~ 5

Author(s):

Verónica Filippa ◽

Daiana Godoy ◽

Edith Perez ◽

Fabian Mohamed

Keyword(s):

Electron Microscopy ◽

Adult Male ◽

Androgen Receptors ◽

Light And Electron Microscopy ◽

Regulatory Mechanisms ◽

Ultrastructural Changes ◽

Morphological Evidence ◽

Pituitary Cells ◽

Pars Distalis ◽

Ventral Region

The aims of the present study were to determine whether castration results in quantitative immunohistochemical changes in androgen receptors (AR), LH-immunoreactive (IR) cells and FSH-IR cells, and to analyse the colocalisation of AR and gonadotropins in the pituitary pars distalis (PD) of viscachas. Pituitaries were processed for light and electron microscopy. AR-IR, LH-IR and FSH-IR cells were detected by immunohistochemistry. In morphometric studies, the percentage of AR-IR, LH-IR, FSH-IR, LH-IR/AR-IR and FSH-IR/AR-IR cells was determined. In intact viscachas, AR were distributed throughout the PD; they were numerous at the caudal end, with intense immunostaining. LH-IR cells and FSH-IR cells were found mainly in the ventral region and at the rostral end of the PD. Approximately 45%–66% of LH-IR cells and 49%–57% of FSH-IR cells expressed AR in the different zones of the PD. In castrated viscachas, there was a significant decrease in the percentage of AR-IR, LH-IR, FSH-IR, and FSH-IR/AR-IR cells. Some pituitary cells from castrated viscachas also exhibited ultrastructural changes. These results provide morphological evidence that gonadal androgens are directly related to the immunolabelling of AR, LH and FSH. Moreover, the colocalisation of AR and FSH is most affected by castration, suggesting the existence of a subpopulation of gonadotrophs with different regulatory mechanisms for hormonal synthesis, storage and secretion.

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Progressive Depletion of Rough Endoplasmic Reticulum in Epithelial Cells of the Small Intestine in Monosodium Glutamate Mice Model of Obesity

BioMed Research International ◽

10.1155/2016/5251738 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 5

Author(s):

Kazuhiko Nakadate ◽

Kento Motojima ◽

Tomoya Hirakawa ◽

Sawako Tanaka-Nakadate

Keyword(s):

Electron Microscopy ◽

Endoplasmic Reticulum ◽

Small Intestine ◽

Epithelial Cells ◽

Rough Endoplasmic Reticulum ◽

Defense Mechanism ◽

Monosodium Glutamate ◽

Light And Electron Microscopy ◽

Obese Mice ◽

Pathological Changes

Chronic obesity is a known risk factor for metabolic syndrome. However, little is known about pathological changes in the small intestine associated with chronic obesity. This study investigated cellular and subcellular level changes in the small intestine of obese mice. In this study, a mouse model of obesity was established by early postnatal administration of monosodium glutamate. Changes in body weight were monitored, and pathological changes in the small intestine were evaluated using hematoxylin-eosin and Nissl staining and light and electron microscopy. Consequently, obese mice were significantly heavier compared with controls from 9 weeks of age. Villi in the small intestine of obese mice were elongated and thinned. There was reduced hematoxylin staining in the epithelium of the small intestine of obese mice. Electron microscopy revealed a significant decrease in and shortening of rough endoplasmic reticulum in epithelial cells of the small intestine of obese mice compared with normal mice. The decrease in rough endoplasmic reticulum in the small intestine epithelial cells of obese mice indicates that obesity starting in childhood influences various functions of the small intestine, such as protein synthesis, and could impair both the defense mechanism against invasion of pathogenic microbes and nutritional absorption.

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CLEMSite, a software for automated phenotypic screens using light microscopy and FIB-SEM

10.1101/2021.03.19.436113 ◽

2021 ◽

Author(s):

José M. Serra Lleti ◽

Anna M. Steyer ◽

Nicole L. Schieber ◽

Beate Neumann ◽

Christian Tischer ◽

...

Keyword(s):

Electron Microscopy ◽

Light Microscopy ◽

Focused Ion Beam ◽

Cultured Cells ◽

Ion Beam ◽

Light And Electron Microscopy ◽

Ultrastructural Level ◽

Reference Points ◽

Grid Pattern ◽

Volume Acquisition

AbstractCorrelative light and electron microscopy (CLEM) combines two imaging modalities, balancing out the limits of one technique with the other. In recent years, Focused Ion Beam Scanning Electron Microscopy (FIB-SEM) has emerged as a flexible method that enables semi-automated volume acquisition at the ultrastructural level. We present a toolset for adherent cultured cells that enables tracking and finding cell regions previously identified in light microscopy, in the FIB-SEM along with automatic acquisition of high-resolution volume datasets. We detect a grid pattern in both modalities (LM and EM), which identifies common reference points. The novel combination of these techniques enables complete automation of the workflow. This includes setting the coincidence point of both ion and electron beams, automated evaluation of the image quality and constantly tracking the sample position with the microscope’s field of view reducing or even eliminating operator supervision. We show the ability to target the regions of interest in EM within 5µm accuracy, while iterating between different targets including unattended data acquisition. Our results demonstrate that executing high throughput volume acquisition in electron microscopy is possible.

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