scholarly journals Combination of Plant Growth Regulators, Maltose, and Partial Desiccation Treatment Enhance Somatic Embryogenesis in Selected Malaysian Rice Cultivar

Plants ◽  
2019 ◽  
Vol 8 (6) ◽  
pp. 144 ◽  
Author(s):  
NG Ja Ming ◽  
Suraiya Binte Mostafiz ◽  
Nur Syafiqoh Johon ◽  
Nur Saliha Abdullah Zulkifli ◽  
Alina Wagiran
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Tissue Culture ◽  
Callus Induction ◽  
Embryogenic Callus ◽  
Histological Analysis ◽  
Naphthalene Acetic Acid ◽  
Partial Desiccation ◽  
Culture Protocol ◽  
Scanning Electron

The development of efficient tissue culture protocol for somatic embryo would facilitate the genetic modification breeding program. The callus induction and regeneration were studied by using different parameters i.e., auxins, cytokinins, and desiccation treatment. Scanning electron microscopy and histological analysis were performed to identify the embryogenic callus for regeneration. The callus percentage results showed that MS (Murashige and Skoog) basal medium supplemented with 3 mg/L 2, 4-D and 30g/L maltose were the optimal callus induction medium for MR220 (80%) and MR220-CL2 (95%). The morphology of the embryogenic callus was confirmed by the SEM (Scanning Electron Microscopy) (presence of extracellular matrix surface network) and later by histological analysis. Finally, MS media supplemented with 0.5 mg/L NAA (Naphthalene Acetic Acid), 2 mg/L kin, and 1 mg/L BAP were selected as the optimum regeneration media treatment while callus desiccated for 48 h was proved to produce more plantlets in MR220 (60%) and MR220-CL2 (73.33%) compared to control treatment (without desiccation). The protocol presented here showed the necessity for the inclusion of partial desiccation as an important step in the tissue culture protocol of Malaysian indica rice genotypes in order to enhance their regeneration potential.

scholarly journals On cestode and digenean parasites of Clarias gariepinus (Burchell, 1822) from the Rietvlei Dam, South Africa

2006 ◽  
Vol 73 (2) ◽  
Author(s):  
M. Barson ◽  
A. Avenant-Oldewage
Keyword(s):  
Electron Microscopy ◽  
South Africa ◽  
Scanning Electron Microscopy ◽  
New Record ◽  
Histological Analysis ◽  
Clarias Gariepinus ◽  
Host Fish ◽  
Mean Intensity ◽  
Anterior Intestine ◽  
Scanning Electron

Sharptooth catfish, Clarias gariepinus, from the Rietvlei Dam near Pretoria, South Africa were examined for internal platyhelminth parasites. Two adult cestodes, Polyonchobothrium clarias (stomach) (prev alence 71 %, mean intensity = 5, n = 7) and Proteocephalus glanduliger (anterior intestine) (prevalence 14 %, mean intensity = 2, n = 7), were found in the gut while metacercariae of one larval digenean, Ornithodiplostomum sp. (prevalence 14 %, mean intensity = 140, n = 7), were found encysted in the muscles. The morphology of these species, based on light and scanning electron microscopy as well as histological analysis, and how they differ from previously described specimens, are discussed. Ornithodiplostomum is a new record in southern Africa. Infection levels of the host fish were mild compared to records from previous surveys.

scholarly journals The mechanism of somite segmentation in the chick embryo

Development ◽  
1979 ◽  
Vol 51 (1) ◽  
pp. 227-243
Author(s):  
Ruth Bellairs
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Tissue Culture ◽  
Chick Embryo ◽  
Neural Tube ◽  
Cell Shape ◽  
Fibroblast Cell ◽  
General Shape ◽  
Major Factors ◽  
Scanning Electron

The segmentation of somites in the chick embryo has been studied by transmission and scanning electron microscopy (stages 8–14). The segmental plate mesoderm consists of loosely arranged mesenchymal cells, whereas the newly formed somites are composed of elongated, spindle-shaped cells arranged radially around a lumen, the myocoele. The diameter of each somite is thus two cells plus the myocoele. Two major factors appear to be responsible for the change in cell shape at segmentation: (1) Each prospective somite cell becomes anchored at one end to the adjacent epithelia (i.e. the neural tube, the notochord, the ectoderm, the endoderm or the aorta) by means of collagen fibrils. These fibrils are already present in the segmental plate before the somites begin to form. (2) A change in cell-to-cell adhesiveness causes the free ends of these cells to adhere to one another. (Bellairs, Curtis & Sanders, 1978). This adhesion is then supplemented by the development of tight junctions proximally in the somite. Because it is anchored at both ends, each somite cell is under tension in much the same way as a fibroblast cell in tissue culture is under tension. Each somite cell therefore becomes elongated and the somite as a whole accommodates its general shape to that of the space available between the adjacent tissues. The arrangement of the cells in the more differentiated somites (stages 17–18) has also been examined and it has been found that the chick resembles Xenopus in that the myotome cells undergo rotation and become orientated in an anteroposterior direction.

Cell monolayer technique using sectionable culture beads

1986 ◽  
Vol 44 ◽  
pp. 254-255
Author(s):  
Margaret E. Hogan
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Tissue Culture ◽  
Experimental Model ◽  
Cell Monolayer ◽  
High Regard ◽  
And Control ◽  
Scanning Electron

The use of tissue culture, as an experimental model, has gained high regard in the study of organism function and control. For this reason the ability to observe these cells has become quite important in both transmission(TEM) and scanning electron microscopy(SEM).Most monolayers of cells have been grown on flat substrates (culture plates and flasks), and have required involved manipulation to prove the desired plane of sectioning. With the use of culture beads much of the handling is eliminated, in fact the procedure is really no different than preparing whole tissue for electron microscopy. Along with the ease of preparation, the beads provide increased tissue per section, and therefore a more broad sampling of the specimens.

Pars flaccida perforation in tissue culture: morphological study

1990 ◽  
Vol 104 (2) ◽  
pp. 91-96 ◽  
Author(s):  
L.-E. Stenfors ◽  
E. G. Olsen ◽  
A. Ö. Henriksen
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Tissue Culture ◽  
Inflammatory Reaction ◽  
Granulation Tissue ◽  
Contact Area ◽  
Morphological Study ◽  
Squamous Epithelium ◽  
Pars Flaccida ◽  
Scanning Electron

AbstractSubtotal pars flaccida perforation was effected in vitro in rat tympanic membranes. The drums were subsequently kept in tissue culture and after various intervals studied by means of light and scanning electron microscopy. No complete covering of the perforation was seen, though a marked thickening and hyperplasia of the outer, keratinizing, squamous epithelium (OE) was evident. The inner, tympanal epithelium (IE) appeared swollen, containing rounded structures in the cytoplasm especially close to the contact area with the OE. Ingrowth of OE onto the tympanal side of the drum was seen particularly in the areas where the IE was sparse and completely lacking. Complete covering of a drum perforation seems to be dependent on the formation of supporting granulation tissue, probably resulting from an inflammatory reaction in the healing area.

The morphology of the parasitic isopod Tachaea chinensis (Isopoda, Cymothoida) revealed through scanning electron microscopy and histological analysis

Crustaceana ◽  
2021 ◽  
Vol 94 (1) ◽  
pp. 63-75
Author(s):  
Xin Li ◽  
Qijun Chen ◽  
Yingdong Li
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Histological Analysis ◽  
Body Cavity ◽  
Future Research ◽  
Negative Effects ◽  
Internal Organs ◽  
Parasitic Isopods ◽  
Commercially Important ◽  
Scanning Electron

Abstract Parasitic isopods have negative effects on several commercially important fishes and crustaceans. However, studies on these parasites, especially on their morphology, are limited. In the present study, scanning electron microscopy and simultaneous histological analysis were carried out to examine the external structure and composition of the internal organs of Tachaea chinensis (Isopoda, Corallanidae). Seven pairs of pereopods are sharp and hook-like, which are used for attaching to the host. Four pairs of the paddle-shaped pleopods indicate that it has the ability to swim freely. Analysis of the mouth appendages revealed that T. chinensis mainly feeds on the host’s blood. Moreover, we found numerous glands, including the salivary glands and hepatopancreas, in the coelom; loose connective tissue was also found in the ventral body cavity, which appeared to be a vestigial gonad. In addition, the description of the gland also provides valuable empirical data for future research.

Preparation of biological monolayers for producing high-resolution scanning electron micrographs Code: PLOS2021 [PONE-D-21-26669] - [EMID:f8569bc7b537f6e4] v1

2021 ◽  
Author(s):  
Shireen Mentor ◽  
Franscious Cummings ◽  
David Fisher ◽  
shireen.mentor not provided
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Tissue Culture ◽  
High Resolution ◽  
Biological Samples ◽  
Scanning Electron Micrographs ◽  
Mouse Brain Endothelial Cells ◽  
Coating Methods ◽  
Scanning Electron

Scanning electron microscopy (SEM) provides a technical platform for nanoscopic mapping of biological structures. Correct preparation of SEM samples can provide an unprecedented understanding of the nexus between cellular morphology and topography. This comparative study critically examines two coating methods for preparing biological samples for scanning electron microscopy, while also providing novel advice on how to prepare in vitro epithelial or endothelial samples for high-resolution scanning-electron microscopy (HR-SEM). Two obstacles often confront the biologist when investigating cellular structures grown under tissue culture conditions, viz., how to prepare and present the biological samples to the HR-SEM microscope without affecting topographical membrane and cellular structural alterations. Firstly, our use of the Millicell cellulose inserts on which to grow our cellular samples in preparation for HR-SEM is both novel and advantageous to comparing the permeability function of cells to their morphological function. Secondly, biological material is often non-conducting, thermally sensitive and fragile and, therefore, needs to be fixed correctly and coated with thin conducting metal to ensure high-resolution detail of samples. Immortalized mouse brain endothelial cells (bEnd5) was used as a basis for describing the preferences in the use of the protocol. We compare two biological sample coating modalities for the visualizing and analysis of texturized, topographical, membranous ultrastructures of brain endothelial cell (BEC) confluent monolayers, namely, carbon and gold:palladium (Au:Pd) sputter coating in preparation for HR-SEM. BEC monolayers sputter-coated with these two modalities produced three-dimensional micrographs which have distinctly different topographical detail from which the nanostructural cellular data can be examined. The two coating methods display differences in the amount of nanoscopic detail that could be resolved in the nanosized membrane cytoarchitecture of BEC monolayers. The micrographical data clearly showed that Au:Pd sputter-coated samples generate descript imagery, providing useful information for profiling membrane nanostructures compared to carbon-coated samples. The recommendations regarding the contrast in two modalities would provide the necessary guidance to biological microscopists in preparing tissue culture samples for HR-SEM.

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