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

1977 ◽  
Vol 55 (18) ◽  
pp. 2419-2436 ◽  
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.

Fine structure and possible functions of the hermaphrodite duct of some pulmonate snails (Mollusca: Gastropoda)

1990 ◽  
Vol 48 (3) ◽  
pp. 68-69
Author(s):  
Alan N. Hodgson
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fine Structure ◽  
Seminal Vesicle ◽  
Reproductive Biology ◽  
Light Microscope ◽  
Light Microscope Level ◽  
Transmission Electron ◽  
Standard Techniques

The hermaphrodite duct of pulmonate snails connects the ovotestis to the fertilization pouch. The duct is typically divided into three zones; aproximal duct which leaves the ovotestis, the middle duct (seminal vesicle) and the distal ovotestis duct. The seminal vesicle forms the major portion of the duct and is thought to store sperm prior to copulation. In addition the duct may also play a role in sperm maturation and degredation. Although the structure of the seminal vesicle has been described for a number of snails at the light microscope level there appear to be only two descriptions of the ultrastructure of this tissue. Clearly if the role of the hermaphrodite duct in the reproductive biology of pulmonatesis to be understood, knowledge of its fine structure is required.Hermaphrodite ducts, both containing and lacking sperm, of species of the terrestrial pulmonate genera Sphincterochila, Levantina, and Helix and the marine pulmonate genus Siphonaria were prepared for transmission electron microscopy by standard techniques.

scholarly journals A tribute to Shinya Inoue and innovation in light microscopy

2004 ◽  
Vol 165 (1) ◽  
pp. 21-26 ◽  
Author(s):  
Karen R. Dell ◽  
Ronald D. Vale
Keyword(s):  
Electron Microscopy ◽  
Light Microscopy ◽  
Light Microscope ◽  
Light And Electron Microscopy ◽  
Single Molecules ◽  
Living Cells ◽  
Dynamic Processes ◽  
New Techniques

The 2003 International Prize for Biology was awarded to Shinya Inoue for his pioneering work in visualizing dynamic processes within living cells using the light microscope. He and his scientific descendants are now pushing light microscopy even further by developing new techniques such as imaging single molecules, visualizing processes in living animals, and correlating results from light and electron microscopy.

Single Processing of Tissue for Light and Electron Microscopy

1977 ◽  
Vol 35 ◽  
pp. 550-551 ◽  
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.

scholarly journals THE FINE STRUCTURE OF THE NUCLEOLUS DURING MITOSIS IN THE GRASSHOPPER NEUROBLAST CELL

1965 ◽  
Vol 24 (3) ◽  
pp. 349-368 ◽  
Author(s):  
Barbara J. Stevens
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
Light Microscope ◽  
Light And Electron Microscopy ◽  
Peripheral Zone ◽  
Structural Components ◽  
Thin Sections ◽  
Nucleolar Material ◽  
Central Regions ◽  
Homogeneous Background

The behavior of the nucleolus during mitosis was studied by electron microscopy in neuroblast cells of the grasshopper embryo, Chortophaga viridifasciata. Living neuroblast cells were observed in the light microscope, and their mitotic stages were identified and recorded. The cells were fixed and embedded; alternate thick and thin sections were made for light and electron microscopy. The interphase nucleolus consists of two fine structural components arranged in separate zones. Concentrations of 150 A granules form a dense peripheral zone, while the central regions are composed of a homogeneous background substance. Observations show that nucleolar dissolution in prophase occurs in two steps with a preliminary loss of the background substance followed by a dispersal of the granules. Nucleolar material reappears at anaphase as small clumps or layers at the chromosome surfaces. These later form into definite bodies, which disappear as the nucleolus grows in telophase. Evidence suggests both a collecting and a synthesizing role for the nucleolus-associated chromatin. The final, mature nucleolar form is produced by a rearrangement of the fine structural components and an increase in their mass.

XVIII.—The Spermatozoon of the Spider BeetlePtinus tectusBoieldieu as seen by Light and Electron Microscopy

1951 ◽  
Vol 64 (3) ◽  
pp. 353-366 ◽  
Author(s):  
Jozef Dlugosz ◽  
John W. Harrold
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Light Microscope ◽  
Light And Electron Microscopy ◽  
Sperm Head ◽  
Central Axis

SynopsisThe mature Ptinid sperm examined under the light microscope is found to be specialised in that the chromatin is not contained within a sperm head but is distributed along a central axis. The migration of chromatin resembles that found in Coccids by Hughes-Schrader (1948). Surrounding the axis is a more flexible helical membrane extending the whole length of the sperm.Under the electron microscope the membrane appears to consist of eighteen or twenty thin fibres and two thick fibres with striated sheaths. Near the posterior end of the membrane the fibres are surrounded by a ring. The structure is simpler than that of mammalian and avian sperms examined by other workers with similar techniques. Under the electron microscope, stages in the migration of chromatin in the immature sperm show a number of discrete opaque bodies which may be chromosomes. The approximate dimensions of the various structures are given.

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

Microscopy ◽  
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.

Selective Staining of Cortical Granules and Golgi Cisternae in Arbacia Punctulata

1969 ◽  
Vol 27 ◽  
pp. 286-287
Author(s):  
Arya K. Bal ◽  
Gilles H. Cousineau
Keyword(s):  
Electron Microscopy ◽  
Light Microscope ◽  
Phosphotungstic Acid ◽  
Dense Material ◽  
Cortical Granules ◽  
Light Microscope Level ◽  
Electron Dense Material ◽  
Selective Staining ◽  
Arbacia Punctulata ◽  
Staining Techniques

Cyto-chemical staining techniques at the light microscope level have revealed the presence of mucopolysaccharides and proteins in the cortical granules of Eichinoderm eggs. In routine electron microscopy preparation the cortical granules appear to have two morphologically distinct components - an electron dense inner component (dark bodies) surrounded by a less-electron dense material. In the present investigation it has been made possible to stain the dense inner material selectively with Phosphotungstic acid (PTA) in non-osmicated aldehyde fixed oocytes and eggs of Arbacia punctulata.

Saltatory Movements of Organelles in Intact Nerves of Rhodnius Prolixus STÅL

1977 ◽  
Vol 70 (1) ◽  
pp. 247-257
Author(s):  
J. P. HESLOP ◽  
E. A. HOWES
Keyword(s):  
Electron Microscopy ◽  
High Power ◽  
Light Microscope ◽  
Light And Electron Microscopy ◽  
Time Lapse ◽  
Rhodnius Prolixus ◽  
Axonal Flow ◽  
Different Temperatures ◽  
Intracellular Organelles

1. Abdominal nerves of Rhodnius prolixus were studied with the light microscope under high-power Nomarski optics with a minimum of surgical interference. The preparation was perfused with bathing solutions which could be changed during time-lapse cinematography. 2. The structure of the nerve trunks was studied by light and electron microscopy. 3. The movements of intracellular organelles are described and discussed. 4. Saltatory movements of organelles, probably mitochondria, were followed at different temperatures. Rate of saltation varied linearly with temperature. 5. Axonal flow (bulk movement of cytoplasm) did not occur in healthy abdominal nerves.

scholarly journals Ultrastructural Dendritic Changes Underlying Diaschisis After Capsular Infarct

2020 ◽  
Vol 79 (5) ◽  
pp. 508-517
Author(s):  
Min-Cheol Lee ◽  
Ra Gyung Kim ◽  
Taebum Lee ◽  
Jo-Heon Kim ◽  
Kyung-Hwa Lee ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Light And Electron Microscopy ◽  
Ultrastructural Level ◽  
Subcortical White Matter ◽  
Ultrastructural Changes ◽  
Pathological Changes ◽  
Hydropic Degeneration ◽  
Mild Degree ◽  
Neuronal Soma ◽  
Axodendritic Synapses

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.

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

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.

Sign in / Sign up

Export Citation Format

Share Document