A Protocol For Digesting Internal Soft Tissues And Mounting Spiders For Scanning Electron Microscopy

Scanning electron microscopy of fish scales has facilitated the application of micro-structures to systematics. Electron microscopy studies have added more information on the structure of the scale and the associated cells, many problems still remain unsolved, because of our incomplete knowledge of the process of calcification. One of the main purposes of these studies has been to study the histology, histochemistry, and ultrastructure of both calcified and decalcified scales, and associated cells, and to obtain more information on the mechanism of calcification in the scales. The study of a calcified scale with the electron microscope is complicated by the difficulty in sectioning this material because of the close association of very hard tissue with very soft tissues. Sections often shatter and blemishes are difficult to avoid. Therefore the aim of this study is firstly to develop techniques for the preparation of cross sections of fish scales for scanning electron microscopy and secondly the application of these techniques for the determination of the structures and calcification of fish scales.

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What Is Considered a Variation of Biomechanical Parameters in Tensile Tests of Collagen-Rich Human Soft Tissues?—Critical Considerations Using the Human Cranial Dura Mater as a Representative Morpho-Mechanic Model

Medicina ◽

10.3390/medicina56100520 ◽

2020 ◽

Vol 56 (10) ◽

pp. 520

Author(s):

Johann Zwirner ◽

Mario Scholze ◽

Benjamin Ondruschka ◽

Niels Hammer

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Soft Tissue ◽

Dura Mater ◽

Soft Tissues ◽

Tensile Tests ◽

Interquartile Range ◽

Tissue Structure ◽

Mechanical Parameters ◽

Scanning Electron

Background and Objectives: Profound knowledge on the load-dependent behavior of human soft tissues is required for the development of suitable replacements as well as for realistic computer simulations. Regarding the former, e.g., the anisotropy of a particular biological tissue has to be represented with site- and direction-dependent particular mechanical values. Contrary to this concept of consistent mechanical properties of a defined soft tissue, mechanical parameters of soft tissues scatter considerably when being determined in tensile tests. In spite of numerous measures taken to standardize the mechanical testing of soft tissues, several setup- and tissue-related factors remain to influence the mechanical parameters of human soft tissues to a yet unknown extent. It is to date unclear if measurement extremes should be considered a variation or whether these data have to be deemed incorrect measurement outliers. This given study aimed to determine mechanical parameters of the human cranial dura mater as a model for human soft tissues using a highly standardized protocol and based on this, critically evaluate the definition for the term mechanical “variation” of human soft tissue. Materials and Methods: A total of 124 human dura mater samples with an age range of 3 weeks to 94 years were uniformly retrieved, osmotically adapted and mechanically tested using customized 3D-printed equipment in a quasi-static tensile testing setup. Scanning electron microscopy of 14 samples was conducted to relate the mechanical parameters to morphological features of the dura mater. Results: The here obtained mechanical parameters were scattered (elastic modulus = 46.06 MPa, interquartile range = 33.78 MPa; ultimate tensile strength = 5.56 MPa, interquartile range = 4.09 MPa; strain at maximum force = 16.58%, interquartile range = 4.81%). Scanning electron microscopy revealed a multi-layered nature of the dura mater with varying fiber directions between its outer and inner surface. Conclusions: It is concluded that mechanical parameters of soft tissues such as human dura mater are highly variable even if a highly standardized testing setup is involved. The tissue structure and composition appeared to be the main contributor to the scatter of the mechanical parameters. In consequence, mechanical variation of soft tissues can be defined as the extremes of a biomechanical parameter due to an uncontrollable change in tissue structure and/or the respective testing setup.

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Ossicle development of the crinoid Florometra serratissima through larval stages

Canadian Journal of Zoology ◽

10.1139/cjz-2016-0195 ◽

2017 ◽

Vol 95 (3) ◽

pp. 183-192 ◽

Cited By ~ 3

Author(s):

Ariane Comeau ◽

Cory D. Bishop ◽

Christopher B. Cameron

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Soft Tissues ◽

Sister Group ◽

Coralline Algae ◽

Rapid Radiation ◽

Larval Stages ◽

Evolution And Development ◽

Feather Star ◽

Scanning Electron

Crinoids are the oldest living class of echinoderm and sister group to the remaining eleutherozoan clade and so are key to discussions on the evolution and development of the echinoderm skeleton. Here we present the intraspecific variation of ossicle development of the feather star Florometra serratissima (A.H. Clark, 1907) during its three larval stages: doliolaria, cystidean, and early pentacrinoid. To induce settlement, larvae were cultured on a sea table in glass bowls containing coralline algae. The soft tissues of 60 larvae were dissolved to isolate and to observe the ossicles with compound microscopy and scanning electron microscopy. From the late doliolaria stage to 56-day-old pentacrinoids, a total of four types of ossicle developed: oral plates, basal plates, columnar stalk ossicles, and an attachment disk. Occasionally, an additional plate was found under the basal plates, which may represent a vestigial infrabasal plate. The shape of the attachment disk was plastic to accommodate the substrate. Crinoid ossicle development is variable in size, shape, and number, and the timing of development is asynchronous; traits that may have contributed to the early rapid radiation and phenotypic disparity of echinoderms.

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Mechanical and Corrosion Behaviour of Some Devices for Ostheosinthesis

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.23.257 ◽

2007 ◽

Vol 23 ◽

pp. 257-260 ◽

Cited By ~ 1

Author(s):

Brandusa Ghiban

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Femoral Fracture ◽

Soft Tissues ◽

Corrosion Behaviour ◽

Structural Features ◽

X Rays ◽

Hard Tissues ◽

Mechanical Devices ◽

Scanning Electron

Orthopaedic implants represent mechanical devices which may be used for different purposes in human skeleton. such as either repairing of soft tissues (ligaments) or hard tissues (fractures. osteotomy. partial or total replacements). The aim of present paper is to put in evidence some macro and micro structural features revealed at state of surface after 5 months of implant in a female femoral fracture. Investigated surfaces were analyzed by optical and scanning electron microscopy and by X-Rays diffraction.

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Technic for the Study of Small, Soft-Bodied Aurelia with Scanning EM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100117030 ◽

1975 ◽

Vol 33 ◽

pp. 682-683

Author(s):

Dorothy B. Spangenberg ◽

William Kuenning

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Soft Tissues ◽

Scanning Em ◽

Scanning Electron ◽

Made In ◽

Sem Studies

Rapid advances have been made in the preservation and preparation of cells and soft tissues of vertebrates for scanning electron microscopy (SEM). These technics, however, only rarely have been applied to small soft-bodied invertebrates. When an effort was made to preserve intact metamorphosing Aurelia polyps (strobilae) for SEM studies, it became apparent that special methodology was needed. The following technic was developed:Aurelia polyps are induced to metamorphose with 1 x 10-5M thyroxine. Strobilae in the desired stage of metamorphosis are fixed in 2 changes of 3% gluteraldehyde for 1 hr. each. They are rinsed 2X in collidine buffer, pH 7.4 (based on). The organisms are dehydrated in grades of acetone from 30% to 100%. To avoid disturbing the strobilae, acetone is added to the dilute acetone every 10 min. to achieve concentrations of 50, 70, and 95%. The strobilae are rinsed 2X in 100% acetone for 5 and 10 minutes each.

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A method for preservation of soft tissues of marine teleosts for scanning electron microscopy

Tissue and Cell ◽

10.1016/s0040-8166(72)80039-9 ◽

1972 ◽

Vol 4 (4) ◽

pp. 687-690 ◽

Cited By ~ 10

Author(s):

Gary H. Dobbs

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Soft Tissues ◽

Scanning Electron

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Exceptional preservation of soft tissue in a new specimen of Eoconfuciusornis and its biological implications

National Science Review ◽

10.1093/nsr/nwx004 ◽

2017 ◽

Vol 4 (3) ◽

pp. 441-452 ◽

Cited By ~ 25

Author(s):

Xiaoting Zheng ◽

Jingmai K. O’Connor ◽

Xiaoli Wang ◽

Yanhong Pan ◽

Yan Wang ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Soft Tissue ◽

Soft Tissues ◽

Support Network ◽

Sexually Dimorphic ◽

Remarkable Similarity ◽

Exceptional Preservation ◽

Internal Support ◽

Scanning Electron

Abstract We report on an exceptional specimen of Eoconfuciusornis preserving rare soft-tissue traces of the ovary and wing. Ovarian follicles preserve a greater hierarchy than observed in Jeholornis and enantiornithines, suggesting confuciusornithiforms evolved higher rates of yolk deposition in parallel with the neornithine lineage. The preserved soft tissues of the wing indicate the presence of a propatagium and postpatagium, whereas an alular patagium is absent. Preserved remnants of the internal support network of the propatagium bear remarkable similarity to that of living birds. Soft tissue suggests the confuciusornithiform propatagium could maintain a cambered profile and generate lift. The feathers of the wing preserve remnants of their original patterning; however, this is not strongly reflected by observable differences under scanning electron microscopy (SEM). The tail plumage lacks elongate rectrices, suggesting that the earliest known confuciusornithiforms were sexually dimorphic in their plumage.

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Pathogenesis of Human Hair Defects

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010005007x ◽

1974 ◽

Vol 32 ◽

pp. 12-13

Author(s):

P.S. Porter ◽

T. Aoyagi ◽

R. Matta

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Human Hair ◽

Standard Techniques ◽

Scanning Electron

Using standard techniques of scanning electron microscopy (SEM), over 1000 human hair defects have been studied. In several of the defects, the pathogenesis of the abnormality has been clarified using these techniques. It is the purpose of this paper to present several distinct morphologic abnormalities of hair and to discuss their pathogenesis as elucidated through techniques of scanning electron microscopy.

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Ultrastructural Analysis of the Salivary Glands of Gromphadorhina Portentosa (Schaum)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100080614 ◽

1977 ◽

Vol 35 ◽

pp. 638-639

Author(s):

P.J. Dailey

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Salivary Glands ◽

Secretory Vesicles ◽

The Past ◽

Transmission Electron ◽

Means Of Transmission ◽

Gromphadorhina Portentosa ◽

Scanning Electron ◽

Topographical Relief

The structure of insect salivary glands has been extensively investigated during the past decade; however, none have attempted scanning electron microscopy (SEM) in ultrastructural examinations of these secretory organs. This study correlates fine structure by means of SEM cryofractography with that of thin-sectioned epoxy embedded material observed by means of transmission electron microscopy (TEM).Salivary glands of Gromphadorhina portentosa were excised and immediately submerged in cold (4°C) paraformaldehyde-glutaraldehyde fixative1 for 2 hr, washed and post-fixed in 1 per cent 0s04 in phosphosphate buffer (4°C for 2 hr). After ethanolic dehydration half of the samples were embedded in Epon 812 for TEM and half cryofractured and subsequently critical point dried for SEM. Dried specimens were mounted on aluminum stubs and coated with approximately 150 Å of gold in a cold sputtering apparatus.Figure 1 shows a cryofractured plane through a salivary acinus revealing topographical relief of secretory vesicles.

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Two- or three-way observations of the identical cell elements within the same sections by LM, TEM and/or SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081279 ◽

1978 ◽

Vol 36 (2) ◽

pp. 82-83 ◽

Cited By ~ 1

Author(s):

Nakazo Watari ◽

Yasuaki Hotta ◽

Yoshio Mabuchi

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Transmission Electron Microscopy ◽

Fine Structure ◽

Light Microscopy ◽

Thin Sections ◽

Transmission Electron ◽

Identical Cell ◽

Electron Microscopes ◽

Scanning Electron

It is very useful if we can observe the identical cell elements within the same sections by light microscopy (LM), transmission electron microscopy (TEM) and/or scanning electron microscopy (SEM) sequentially, because, the cell fine structure can not be indicated by LM, while the color is; on the other hand, the cell fine structure can be very easily observed by EM, although its color properties may not. However, there is one problem in that LM requires thick sections of over 1 μm, while EM needs very thin sections of under 100 nm. Recently, we have developed a new method to observe the same cell elements within the same plastic sections using both light and transmission (conventional or high-voltage) electron microscopes.In this paper, we have developed two new observation methods for the identical cell elements within the same sections, both plastic-embedded and paraffin-embedded, using light microscopy, transmission electron microscopy and/or scanning electron microscopy (Fig. 1).

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