scholarly journals Ultrastructure and functional morphology of the appendages in the reef-building sedentary polychaete Sabellaria alveolata (Annelida, Sedentaria, Sabellida)

BMC Zoology ◽  
2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Christian Meyer ◽  
Thomas André ◽  
Günter Purschke
Keyword(s):  
Blood Vessels ◽  
Functional Morphology ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Entire Body ◽  
Receptor Cells ◽  
Body Regions ◽  
Motile Cilia ◽  
Anterior Segments

Abstract Background The sedentary polychaete Sabellaria alveolata, the sandcastle or honeycomb worm, possesses four different kinds of appendages besides the parapodia: opercular papillae, tentacular filaments, palps, and branchiae. It exhibits a highly specialized anterior end, the operculum, formed by the prostomium, peristomium, and two anterior segments. The operculum comprises opercular papillae, tentacular filaments, and palps. Paired branchiae are present from the second thoracic chaetiger onwards on the posteriorly following segments except for the last ones. Ultrastructural data on these appendages are either scanty, incomplete, or even lacking in Sabellariidae. In order to analyze their functional morphology, to bridge the data gap, and providing data for future phylogenetic and evolutionary analyses, we investigated the appendages of S. alveolata by applying light microscopy, confocal laser scanning microscopy, scanning, and transmission electron microscopy. Results In S. alveolata the entire body is covered by a thin cuticle characterized by the absence of layers of parallel collagen fibers with no differentiation between the various body regions including the branchiae. The opercular papillae bear numerous tufts of receptor cells and lack motile cilia. The tentacular filaments show a distinctive pattern of motile cilia. Their most conspicuous morphological feature is a cell-free cartilaginous endoskeletal structure enclosed by ECM. Besides musculature the filaments include a single coelomic cavity but blood vessels are absent. The palps are ciliated and possess two coelomic cavities and a single blind-ending internal blood vessel. Besides external ciliation and receptor cells, the coelomate branchiae are highly vascularized and equipped with numerous blood spaces extending deep between the epidermal cells resulting in low diffusion distances. Conclusions All appendages, including the branchiae, bear receptor cells and, as such, are sensory. The opercular papillae resemble typical parapodial cirri. In contrast, the tentacular filaments have a triple function: sensing, collecting and transporting particles. A similarity to branchiae can be excluded. The palps are typical grooved palps. A revised classification of polychaete branchiae is suggested; thereby, the branchiae of S. alveolata belong to the most common type comprising coelom, musculature, and blood vessels. The results indicate that diffusion distances between blood and environment have been underestimated in many cases.

scholarly journals Ultrastructure and Functional Morphology of the Appendages in the Reef-Building Sedentary Polychaete Sabellaria Alveolata (Annelida, Sedentaria, Sabellida)

2020 ◽  
Author(s):  
Christian Meyer ◽  
Thomas André ◽  
Günter Purschke
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Blood Vessels ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Entire Body ◽  
Receptor Cells ◽  
Body Regions ◽  
Transmission Electron

Abstract Background: The sedentary polychaete Sabellaria alveolata, the sandcastle or honeycomb worm, possesses four different kinds of appendages besides the parapodia: opercular papillae, tentacular filaments, palps, and branchiae. It exhibits a highly specialized anterior end, the operculum, formed by the prostomium, peristomium, and two anterior segments. Besides the median organ, the operculum comprises opercular papillae, tentacular filaments, and palps. Paired branchiae are present from the second thoracic chaetiger onwards on the posteriorly following segments except for the last ones. Only the palps have been studied thus far by transmission electron microscopy in late larvae of a different species. In order to bridge the data gap, we investigated the appendages of S. alveolata by applying light microscopy, confocal laser scanning microscopy, scanning, and transmission electron microscopy. Results: In S. alveolata the entire body is covered by a thin cuticle characterized by the absence of layers of parallel collagen fibers with no differentiation between the various body regions including the branchiae. The opercular papillae bear numerous tufts of receptor cells and lack motile cilia. The tentacular filaments show a distinctive ciliation pattern; their most conspicuous morphological feature is their cell-free cartilaginous endoskeletal structure enclosed by ECM. Besides musculature the filaments include a single coelomic cavity but blood vessels are absent. The palps are ciliated with two coelomic cavities and a single blind-ending blood vessel. Besides external ciliation and receptor cells, the coelomate branchiae are highly vascularized and equipped with numerous blood spaces extending deep into the basal regions of the epidermal cells (diffusion distances: 150–400nm). Conclusions: All appendages, including the branchiae, bear receptor cells and, as such, are sensory. The opercular papillae resemble typical parapodial cirri. In contrast, the tentacular filaments have a double function: sensing, collecting and transporting particles. A similarity to branchiae can be excluded. The palps are typical grooved palps similar to another sabellariid studied. A revised classification of polychaete branchiae is suggested; thereby, the branchiae of S. alveolata belong to the most common type comprising coelom, musculature, and blood vessels. The results indicate that diffusion distances between blood and environment have been underestimated in many cases.

scholarly journals Single-laser three-color immunolabeling of a histological section by laser scanning microscopy: application to senile plaque-related structures in post-mortem human brain tissue.

1995 ◽  
Vol 43 (1) ◽  
pp. 103-106 ◽  
Author(s):  
T Uchihara ◽  
H Kondo ◽  
H Akiyama ◽  
K Ikeda
Keyword(s):  
Blood Vessels ◽  
Brain Tissue ◽  
Tissue Section ◽  
Laser Scanning ◽  
Histological Section ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Post Mortem ◽  
Activated Microglia ◽  
Hla Dr

We describe a method for observing three-color immunofluorescence simultaneously in a histological section under a confocal laser scanning microscope. In this study we investigated the spatial relationship of blood vessels, reactive microglia, and amyloid beta-protein (A beta) deposits in post-mortem brain tissue of patients with Alzheimer's disease. HLA-DR was employed as a marker for activated microglia and von Willebrand factor (vWF) as a marker for vascular endothelial cells. HLA-DR was labeled with R-phycoerythrin (R-PE) and vWF with fluorescein isothiocyanate. A beta-protein was immunostained with the tandem conjugate of R-PE and cyanin 5. Three images were obtained serially by scanning a tissue section with a 488-nm laser beam in combination with an appropriate emission filter for each fluorochrome. Overlaying of these three images permitted simultaneous observation of three distinct structures: activated microglia, blood vessels, and A beta deposits. This technique provides an improved way to study the localization of three different antigens in a single tissue section.

scholarly journals Comparative myoanatomy of Tardigrada: new insights from the heterotardigrades Actinarctus doryphorus (Tanarctidae) and Echiniscoides sigismundi (Echiniscoididae)

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Dennis Krog Persson ◽  
Kenneth Agerlin Halberg ◽  
Ricardo Cardoso Neves ◽  
Aslak Jørgensen ◽  
Reinhardt Møbjerg Kristensen ◽  
...  
Keyword(s):  
Laser Scanning ◽  
Phylogenetic Analyses ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Ground Pattern ◽  
Extreme Stress ◽  
Body Regions ◽  
Attachment Sites ◽  
Muscle Groups ◽  
Trunk Musculature

Abstract Background Tardigrada is a group of microscopic invertebrates distributed worldwide in permanent and temporal aquatic habitats. Famous for their extreme stress tolerance, tardigrades are also of interest due to their close relationship with Arthropoda and Cycloneuralia. Despite recent efforts in analyzing the musculature of a number of tardigrade species, data on the class Heterotardigrada remain scarce. Aiming to expand the current morphological framework, and to promote the use of muscular body plans in elucidating tardigrade phylogeny, the myoanatomy of two heterotardigrades, Actinarctus doryphorus and Echiniscoides sigismundi, was analyzed by cytochemistry, scanning electron and confocal laser scanning microscopy and 3D imaging. We discuss our findings with reference to other tardigrades and internal phylogenetic relationships of the phylum. Results We focus our analyses on the somatic musculature, which in tardigrades includes muscle groups spanning dorsal, ventral, and lateral body regions, with the legs being musculated by fibers belonging to all three groups. A pronounced reduction of the trunk musculature is seen in the dorsoventrally compressed A. doryphorus, a species that generally has fewer cuticle attachment sites as compared to E. sigismundi and members of the class Eutardigrada. Interestingly, F-actin positive signals were found in the head appendages of A. doryphorus. Our analyses further indicate that cross-striation is a feature common to the somatic muscles of heterotardigrades and that E. sigismundi—as previously proposed for other echiniscoidean heterotardigrades—has relatively thick somatic muscle fibers. Conclusions We provide new insights into the myoanatomical differences that characterize distinct evolutionary lineages within Tardigrada, highlighting characters that potentially can be informative in future phylogenetic analyses. We focus our current analyses on the ventral trunk musculature. Our observations suggest that seven paired ventromedian attachment sites anchoring a large number of muscles can be regarded as part of the ground pattern of Tardigrada and that fusion and reduction of cuticular attachment sites is a derived condition. Specifically, the pattern of these sites differs in particular details between tardigrade taxa. In the future, a deeper understanding of the tardigrade myoanatomical ground pattern will require more investigations in order to include all major tardigrade lineages.

3-D imaging of cells using a confocal laser scanning microscope and digital image processing

1988 ◽  
Vol 46 ◽  
pp. 96-97
Author(s):  
Thomas M. Jovin ◽  
Michel Robert-Nicoud ◽  
Donna J. Arndt-Jovin ◽  
Thorsten Schormann
Keyword(s):  
Laser Scanning ◽  
Confocal Laser Scanning Microscope ◽  
Laser Scanning Microscopy ◽  
Confocal Laser Scanning ◽  
Confocal Laser ◽  
Scanning Microscope ◽  
Laser Scanning Microscope ◽  
Biochemical Processes ◽  
Adjacent Structures

Light microscopic techniques for visualizing biomolecules and biochemical processes in situ have become indispensable in studies concerning the structural organization of supramolecular assemblies in cells and of processes during the cell cycle, transformation, differentiation, and development. Confocal laser scanning microscopy offers a number of advantages for the in situ localization and quantitation of fluorescence labeled targets and probes: (i) rejection of interfering signals emanating from out-of-focus and adjacent structures, allowing the “optical sectioning” of the specimen and 3-D reconstruction without time consuming deconvolution; (ii) increased spatial resolution; (iii) electronic control of contrast and magnification; (iv) simultanous imaging of the specimen by optical phenomena based on incident, scattered, emitted, and transmitted light; and (v) simultanous use of different fluorescent probes and types of detectors.We currently use a confocal laser scanning microscope CLSM (Zeiss, Oberkochen) equipped with 3-laser excitation (u.v - visible) and confocal optics in the fluorescence mode, as well as a computer-controlled X-Y-Z scanning stage with 0.1 μ resolution.

Vacuoles Induced in Mammalian Cells by Helicobacter Cytotoxin are Acidic Organelles

1990 ◽  
Vol 48 (3) ◽  
pp. 168-169
Author(s):  
M. H. Chestnut ◽  
C. E. Catrenich
Keyword(s):  
Acridine Orange ◽  
Mammalian Cells ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Ulcer Disease ◽  
Gastroduodenal Disease ◽  
H Pylori

Helicobacter pylori is a non-invasive, Gram-negative spiral bacterium first identified in 1983, and subsequently implicated in the pathogenesis of gastroduodenal disease including gastritis and peptic ulcer disease. Cytotoxic activity, manifested by intracytoplasmic vacuolation of mammalian cells in vitro, was identified in 55% of H. pylori strains examined. The vacuoles increase in number and size during extended incubation, resulting in vacuolar and cellular degeneration after 24 h to 48 h. Vacuolation of gastric epithelial cells is also observed in vivo during infection by H. pylori. A high molecular weight, heat labile protein is believed to be responsible for vacuolation and to significantly contribute to the development of gastroduodenal disease in humans. The mechanism by which the cytotoxin exerts its effect is unknown, as is the intracellular origin of the vacuolar membrane and contents. Acridine orange is a membrane-permeant weak base that initially accumulates in low-pH compartments. We have used acridine orange accumulation in conjunction with confocal laser scanning microscopy of toxin-treated cells to begin probing the nature and origin of these vacuoles.

Use of confocal laser scanning microscopy and a computer model to understand ink cavitation and filamentation

TAPPI Journal ◽  
2010 ◽  
Vol 9 (10) ◽  
pp. 7-15
Author(s):  
HANNA KOIVULA ◽  
DOUGLAS BOUSFIELD ◽  
MARTTI TOIVAKKA
Keyword(s):  
Laser Scanning ◽  
Confocal Laser Scanning Microscope ◽  
Laser Scanning Microscopy ◽  
Confocal Laser Scanning ◽  
Confocal Laser ◽  
Print Quality ◽  
Length Scale ◽  
Offset Printing ◽  
Significant Difference ◽  
Printing Speed

In the offset printing process, ink film splitting has an important impact on formation of ink filaments. The filament size and its distribution influence the leveling of ink and hence affect ink setting and the print quality. However, ink filaments are difficult to image due to their short lifetime and fine length scale. Due to this difficulty, limited work has been reported on the parameters that influence filament size and methods to characterize it. We imaged ink filament remains and quantified some of their characteristics by changing printing speed, ink amount, and fountain solution type. Printed samples were prepared using a laboratory printability tester with varying ink levels and operating settings. Rhodamine B dye was incorporated into fountain solutions to aid in the detection of the filaments. The prints were then imaged with a confocal laser scanning microscope (CLSM) and images were further analyzed for their surface topography. Modeling of the pressure pulses in the printing nip was included to better understand the mechanism of filament formation and the origin of filament length scale. Printing speed and ink amount changed the size distribution of the observed filament remains. There was no significant difference between fountain solutions with or without isopropyl alcohol on the observed patterns of the filament remains.

ACTIVATED SLUDGE FLOC CHARACTERIZATION BY CONFOCAL LASER SCANNING MICROSCOPY

2012 ◽  
Vol 11 (3) ◽  
pp. 669-674 ◽  
Author(s):  
Szabolcs Szilveszter ◽  
Botond Raduly ◽  
Szilard Bucs ◽  
Beata Abraham ◽  
Szabolcs Lanyi ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Confocal Laser Scanning Microscopy ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Confocal Laser Scanning ◽  
Scanning Microscopy ◽  
Confocal Laser
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