The comparative ultrastructure of spermatozoa from Bothrimonus sturionis Duv. 1842 (Pseudophyllidea), Pseudanthobothrium hanseni Baer, 1956 (Tetraphyllidea), and Monoecocestus americanus Stiles, 1895 (Cyclophyllidea)

1984 ◽  
Vol 62 (6) ◽  
pp. 1059-1066 ◽  
Author(s):  
Barbara M. MacKinnon ◽  
Michael D. B. Burt
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Plasma Membrane ◽  
Main Body ◽  
Posterior Portion ◽  
Transmission Electron ◽  
Dense Nucleus ◽  
Comparative Ultrastructure ◽  
Electron Lucent ◽  
Mature Spermatozoa

The mature spermatozoa from Bothrimonus sturionis (Pseudophyllidea), Pseudanthobothrium hanseni (Tetraphyllidea), and Monoecocestus americanus (Cyclophyllidea) were examined using transmission electron microscopy. Transverse sections of the sperm of B. sturionis indicate that the number of sperm axonemes varies from one to eight, with approximately one-third of the sperm containing two axonemes. Likewise, the number of peripheral microtubules lying just within the external plasma membrane varies from 12 to 20. The nucleus is electron lucent and fibrous in appearance. The spermatozoa of B. sturionis show great variation in the material examined and the majority of them are believed to be aberrant. The spermatozoon of P. hanseni contains a single axoneme with the nucleus wrapped in a crescent around it in the anterior region of the sperm. The posterior portion of the spermatozoon is characterized by a helical flange which projects from the main body of the sperm. The spermatozoon of M. americanus is elongate and slender, containing a single axoneme with an electron-dense nucleus coiled around it in the anterior one-third of the sperm. Electron-opaque bodies, which may be glycogen, fill the cytoplasm. The spermatozoa of all three species contain neither an acrosome nor mitochondria. The flagella of all the spermatozoa have a 9 + "1" arrangement of microtubules. The importance of the ultrastructure of spermatozoa in the phylogeny and taxonomy of cestodes is discussed.

The Comparative Ultrastructure of Fibrin Induced by Thrombin and by Staphylocoagulase

1975 ◽  
Vol 34 (01) ◽  
pp. 223-235 ◽  
Author(s):  
M. J. S King ◽  
M. S Morris ◽  
M Tager
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
T Test ◽  
Test Analysis ◽  
A Value ◽  
Transmission Electron ◽  
The Mean ◽  
Comparative Ultrastructure

SummaryFibrin induced by the action of thrombin and by staphylocoagulase was studied by transmission electron microscopy.Periodic striations were consistently observed in the negatively stained preparations of both fibrins. When 4200 major periods in the thrombin fibrin system were measured the mean length was 228 Å. For 3666 major periods in the coagulase fibrin system the mean length was 223 Å. While the T test analysis of these values gave a value of 10, it is noteworthy that the differences are well within the scatter of periodicity reported in the literature for thrombin-induced fibrin.Gross inspection of the preparations indicated that the coagulase-induced fibrin had a knottier appearance and was accompanied by a greater amount of background debris than the thrombin-induced fibrin.

scholarly journals Comparative ultrastructure of the radiolar crown in Sabellida (Annelida)

Zoomorphology ◽  
2020 ◽  
Author(s):  
Ekin Tilic ◽  
Greg W. Rouse ◽  
Thomas Bartolomaeus
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Characteristic Feature ◽  
Water Currents ◽  
Internal Stabilization ◽  
Transmission Electron ◽  
Phylogenetic Lineages ◽  
Histology And Immunohistochemistry ◽  
Comparative Ultrastructure

AbstractThree major clades of tube-dwelling annelids are grouped within Sabellida: Fabriciidae, Serpulidae and Sabellidae. The most characteristic feature of these animals is the often spectacularly colorful and flower-like radiolar crown. Holding up such delicate, feathery appendages in water currents requires some sort of internal stabilization. Each of the above-mentioned family-ranked groups has overcome this problem in a different way. Herein we describe the arrangement, composition and ultrastructure of radiolar tissues for fabriciids, sabellids and serpulids using transmission electron microscopy, histology and immunohistochemistry. Our sampling of 12 species spans most of the phylogenetic lineages across Sabellida and, from within Sabellidae, includes representatives of Myxicolinae, Sabellinae and the enigmatic sabellin Caobangia. We further characterize the ultrastructure of the chordoid cells that make up the supporting cellular axis in Sabellidae and discuss the evolution of radiolar tissues within Sabellida in light of the recently published phylogeny of the group.

Ultrastructural aspects of coated vesicles in tobacco protoplasts

1981 ◽  
Vol 59 (7) ◽  
pp. 1307-1313 ◽  
Author(s):  
P. van der Valk ◽  
L. C. Fowke
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Plasma Membrane ◽  
Coated Vesicles ◽  
Thin Sections ◽  
Tobacco Protoplasts ◽  
Vesicle Membranes ◽  
Transmission Electron ◽  
Large Numbers ◽  
Inner Surface

The ultrastructure and distribution of coated vesicles in isolated tobacco protoplasts were investigated using transmission electron microscopy of thin sections of whole protoplasts and stained plasma membrane preparations obtained by osmotic bursting of protoplasts attached to coated microscope grids. Large numbers of coated vesicles were associated with both the plasma membrane and the maturing face of dictyosomes. Dictyosome associated coated vesicles were smaller and had less distinct coats and vesicle membranes than those associated with the plasma membrane. Honeycomb structures believed to be aggregations of coats were also associated with the inner surface of the plasma membrane. Our data suggest that coated vesicles are produced by the Golgi apparatus, fuse with the plasma membrane, their coats remaining attached, at least temporarily, to the plasma membrane inner surface.

Vitellocyte ultrastructure in the cestode Didymobothrium rudolphii (Monticelli, 1890): possible evidence for the recognition of divergent taxa within the Spathebothriidea

2006 ◽  
Vol 51 (4) ◽  
Author(s):  
Larisa Poddubnaya ◽  
David Gibson ◽  
Zdzisław Świderski ◽  
Peter Olson
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Lipid Droplets ◽  
Interstitial Tissue ◽  
Morphological Parameters ◽  
Transmission Electron ◽  
Shell Globule ◽  
Didymobothrium Rudolphii ◽  
First Time ◽  
Electron Lucent

AbstractIn the spathebothriidean tapeworm Didymobothrium rudolphii (Monticelli, 1890) the fine structure of the vitellocytes at different stages of their development within the vitelline follicles, vitelline ducts and uterus was studied for the first time using transmission electron microscopy. The vitellocyte inclusions of D. rudolphii are shell globule clusters containing tightly packed shell globules associated with a matrix of moderate electron density, glycogen granules, large electron-lucent lipid droplets (up to 3 μm in diameter), and, occasionally, a lipid droplet may occur in the nucleus of the vitellocytes. The diameter of the clusters ranges from 0.4 to 2.5 μm, the number of shell globules in the clusters varies from 8 to 45, and the size of the globules ranges from 0.12 to 0.25 μm and they are of approximately homogeneous sizes within a cluster. Most vitellocyte lipid droplets have a heterogeneous configuration with a ‘cavity’ inside them when they are within vitelline ducts and intrauterine eggs. Vitellocytes of the eggs contain dark concentric bodies and lipid droplets. The interstitial tissue has a syncytial structure. The morphological parameters of the diameter and shape of shell globule clusters, arrangement of shell globules in clusters, number and diameter of globules within clusters, types of lipid droplets and presence of dark concentric bodies are compared with those of two other spathebothriidean genera, Cyathocephalus and Diplocotyle. The comparative data demonstrate that vitelline material morphology has unique features in three spathenothriidean genera and may be used as evidence for the recognition of separate taxa.

Ultrastructure of Mucous Blanket in Otitis Media with Effusion

1988 ◽  
Vol 97 (3) ◽  
pp. 313-317 ◽  
Author(s):  
Masashi Inagaki ◽  
Yasuo Sakakura ◽  
Yuichi Majima ◽  
Takeshi Shimizu ◽  
Kotaro Ukai
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Otitis Media ◽  
Middle Ear ◽  
Otitis Media With Effusion ◽  
Ciliated Cells ◽  
Ciliary Movement ◽  
Mucous Layer ◽  
Transmission Electron ◽  
Electron Lucent

We used transmission electron microscopy to study the mucous blanket of the promontory from children with otitis media with effusion. The vast majority of the epithelial cells were secretory, and the rest were ciliated. The mucous blanket consisted of the electron-lucent periciliary fluid and the mucous layer. In the mucous layer, two layers were identified: An inner layer with migrating cells, and an outer layer with specks. Moreover, there was a lucent zone over the nonciliated surface that was as high as the microvilli. The thickness of the periciliary layer was predominantly as great as that of the ciliary tips, which just make contact with the mucous layer; however, the mucous layer occasionally penetrated into the periciliary space. These findings indicated that there is a mucociliary dysfunction in the middle ear caused by a decrease in the number of ciliated cells, and an abnormal interaction between cilia and mucus that would interfere with ciliary movement. Thus, such a system would fail to transport the mucous blanket.

Ultrastructure of sperm development in the genus Ditylenchus (Nematoda: Anguinidae)

Nematology ◽  
2015 ◽  
Vol 17 (3) ◽  
pp. 313-324 ◽  
Author(s):  
Dieter Slos ◽  
Pooria Ensafi ◽  
Myriam Claeys ◽  
Vladimir V. Yushin ◽  
Wilfrida Decraemer ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Outer Membrane ◽  
Higher Plants ◽  
Transmission Electron ◽  
Sperm Development ◽  
Ditylenchus Dipsaci ◽  
Mature Spermatozoa ◽  
Formation Of Complexes

Spermatogenesis in Ditylenchus arachis and D. dipsaci was studied using transmission electron microscopy. Spermatogenesis includes the formation of complexes of fibrous bodies (FB) and membranous organelles (MO) in the spermatocytes, which dissociate in separated MO and FB in the spermatids. Immature spermatozoa are unpolarised cells with separate FB and MO. Mature spermatozoa are arranged in chains. Ditylenchus dipsaci is unique in having MO that have already fused with the outer membrane in immature spermatozoa and have mature spermatozoa in the male testis, proving that not only insemination plays a role in spermiogenesis. Contrary to what has been described before, spermatogenesis in Ditylenchus, and other early diverging Tylenchomorpha, follow the typical ‘rhabditid’ pattern, while the absence of MO within Tylenchomorpha appears to be an apomorphic trait for the molecular defined clade of tylenchids that exclusively parasitise higher plants. This confirms the value of traits related to spermatogenesis in nematode phylogeny.

scholarly journals Immunogold-labelling localization of chlorophyllase at different developmental stages of Pachira macrocarpa leaves

2021 ◽  
Author(s):  
Tzan-Chain Lee ◽  
Kuan-Hung Lin ◽  
Chang-Chang Chen ◽  
Tin-Han Shih ◽  
Meng-Yuan Huang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Cell Wall ◽  
Plasma Membrane ◽  
Thylakoid Membrane ◽  
Developmental Stages ◽  
Higher Plants ◽  
Plant Cells ◽  
Immunogold Labelling ◽  
Transmission Electron

Abstract Background: Chlorophyllases (Chlases) are housekeeping proteins in plant cells. The dephytylating enzymes can catalyze chlorophyll (Chl) to form chlorophyllide, but the distribution of Chlases in plant cells is still an interesting debate. In this study, antibody of PmCLH2 was made and used by immunogold-labelling technique to detect the location of Chlase of Pachira macrocarpa (Pm) leaves at four developmental stages, including young, mature, yellowing, and senesced stages. Results: The transmission electron microscopy results show that Chlases were comprehensively found in portions of chloroplast, such as the inner membrane of the envelope, grana, and the thylakoid membrane of the chloroplast, cytosol, and vacuoles at young, mature, and yellowing stages of Pm leaves, but not in the cell wall, plasma membrane, mitochondria, and nucleus. Conclusions: PmChlases were mainly detected in vacuoles at the senescent stage, but a few were found in the chloroplasts. A pathway is proposed to explain the birth and death of Chl, Chlase, and chloroplasts in higher plants.

scholarly journals Ultrastructure of sporophyte of Cladosiphon okamuranus Tokida (Ectocarpales, Phaeophyceae)

1970 ◽  
Vol 38 (2) ◽  
pp. 177-180 ◽  
Author(s):  
Qinghua Zhu ◽  
Xuecheng Zhang ◽  
KKIU Arunakumara
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Cell Wall ◽  
Plasma Membrane ◽  
Key Words ◽  
Hair Cells ◽  
Brown Algae ◽  
Lipid Bodies ◽  
Transmission Electron ◽  
Cladosiphon Okamuranus

Transmission Electron Microscopy of 35 day old culture of Cladosiphon okamuranus Tokida, revealed several chloroplasts and other organelles in each cell of assimilatory filaments. Each chloroplast possesses single pyrenoid and Lipid bodies while in hair cells, there were few chloroplasts clinging to plasma-membrane and many pathholes were seen in the cell wall. Key words: Cladosiphon okamuranus; Brown algae; Ultrastructure; Pathhole DOI: 10.3329/bjb.v38i2.5143 Bangladesh J. Bot. 38(2): 177-180, 2009 (December)  

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