scholarly journals Chemical Treatments for Insect Cell Differentiation: The Effects of 20-Hydroxyecdysone and Veratridine on Cultured Spodoptera frugiperda (Sf21) Insect Cell Ultrastructure

Insects ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 32
Author(s):  
Lacey J. Jenson ◽  
James J. Becnel ◽  
Jeffrey R. Bloomquist
Keyword(s):  
Electron Microscopy ◽  
Spodoptera Frugiperda ◽  
Insect Cell ◽  
Culture Medium ◽  
Cell Ultrastructure ◽  
Chemical Treatments ◽  
Cytoplasmic Vacuoles ◽  
Transmission Electron ◽  
Insect Cell Cultures ◽  
Ecdysone Agonist

Previous studies have shown that insect cell cultures stop dividing, form clumps, and can be induced to grow processes reminiscent of axons, when the culture medium is supplemented with 20-hydroxyecdysone, insulin, or an agent that mimics their action, such as the ecdysone agonist, methoxyfenozide. Those cell growing processes resemble nerve cells, and the present study evaluates the ultrastructure of these cultures by transmission electron microscopy. Sf21 cells treated with 20-hydroxyecdysone (with or without veratridine amendment) and subjected to ultrastructural analysis had a similar somatic appearance to control cells, with slight changes in organelles and organization, such as a greater number of cytoplasmic vacuoles and mitochondrial granules. Finger-like projections were observed between control and treated cells. However, no structural markers of synaptic contacts (e.g., vesicles or synaptic thickenings) were observed in controls, 20-hydroxyecdysone, or 20-hydroxyecdysone + veratridine treated cells. It is concluded that additional agents would be required to induce functional synaptogenesis in Sf21 cells.

Cis-Diamminedichloroplatinum (II) Ototoxicity in the Guinea Pig

1981 ◽  
Vol 89 (4) ◽  
pp. 638-645 ◽  
Author(s):  
Scott A. Estrem ◽  
Richard W. Babin ◽  
Jai H. Ryu ◽  
Kenneth C. Moore
Keyword(s):  
Electron Microscopy ◽  
Hair Cells ◽  
Supporting Cell ◽  
Cell Ultrastructure ◽  
Outer Hair Cells ◽  
Detectable Change ◽  
Supporting Cells ◽  
Apical Portion ◽  
Ultrastructural Evidence ◽  
Transmission Electron

Cochleas from 12 guinea pigs were evaluated using light, scanning, and transmission electron microscopy after systemic administration of cis-diamminedichloroplatinum (cis-DDP). Administration of cis-DDP resulted in loss of the Preyer reflex and degeneration of outer hair cells (OHC) with increased dose. The OHC degeneration was most pronounced in the basal turns of the cochlea with greatest severity in the inner row. Ultrastructural evidence of OHC degeneration included dilatation of the parietal membranes, softening of the cuticular plate, increased vacuolization and increased numbers of lysosome-like bodies in the apical portion of the cell. Supporting cells appeared more sensitive than OHC. Alteration of supporting cell ultrastructure preceded detectable change in OHC. Injury to the supporting cells was noted with intracellular vesiculation and increased autophagocytosis.

scholarly journals Ultrastructural calli analysis of Inga vera Willd. subsp. Affinis (DC.) T.D. Penn

2010 ◽  
Vol 34 (5) ◽  
pp. 789-796 ◽  
Author(s):  
Vanessa Cristina Stein ◽  
Renato Paiva ◽  
Daiane Peixoto Vargas ◽  
Fernanda Pereira Soares ◽  
Eduardo Alves ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Culture Medium ◽  
Cell Development ◽  
Nodal Segments ◽  
Nodal Segment ◽  
Ms Medium ◽  
Flower Buds ◽  
Embryo Formation ◽  
Transmission Electron ◽  
Explant Source

Subcellular changes are relevant to understand plant organogenesis and embryogenesis in the early stages of cell development. The cytology during cell development in tissue culture is however still poorly characterized. This study aimed to characterize the ultrastructural differences related to callogenesis of anthers, ovaries, leaf and nodal segments of Inga vera Willd. subsp. Affinis (DC.) T.D. Penn. Flower buds, nodal segments and leaves were disinfected and inoculated in test tubes containing MS medium with 3% sucrose and 4.5µM 2.4-D, except for leaf callogenesis, where 9µM of this auxin was used, and for the callogenesis of anthers and ovaries, where the culture medium was enriched with 0.25% activated charcoal and 90µM PVP. After 45 days in culture medium, the anther, ovary, leaf and nodal segment calli were fixed in Karnovisky and prepared for visualization by scanning and transmission electron microscopy. Ultrastructural differences were observed among the callus cells of anthers, ovaries, segments and leaves. There was no evidence of somatic embryo formation in the anther, leaf and nodal segment calli, in spite of some embryogenic characteristics in the cells. The ovary calli, with indications of embryo formation, seem to be the most responsive explant source for embryogenesis.

Paracrystalline bundles of large tubules, induced in vitro by Mebendazole in Cysticercus cellulosae

Parasitology ◽  
1981 ◽  
Vol 83 (3) ◽  
pp. 513-518 ◽  
Author(s):  
J. P. Laclette ◽  
Marie Therese Merchant ◽  
Kaethe Willms ◽  
L. Cañedo
Keyword(s):  
Electron Microscopy ◽  
Culture Medium ◽  
Morphological Changes ◽  
Bladder Wall ◽  
Secretory Cells ◽  
External Diameter ◽  
Nematode Larvae ◽  
Transmission Electron ◽  
Cysticercus Cellulosae

SUMMARYThe effect of the anthelmintic Mebendazole on Cysticercus cellulosae maintained in culture medium was studied by transmission electron microscopy. In addition to the well-known morphological changes induced by Mebendazole in other cestode and nematode larvae, it also induced the cytoplasmic appearance of paracrystalline bundles in the secretory cells of the bladder wall. These bundles were formed by groups of large parallel tubules arranged in a hexagonal-like pattern. The tubules, which had an external diameter of about 50 nm and a length that might exceed 5 μm, were surrounded by a matrix and a distance between neighbouring tubules of 80–120 nm centre to centre was estimated. The tubules were stable to colchicine and low temperature. The temporary appearance of bundles is described and some alternative explanations on their origin are advanced.

Surface Disorder and Exfoliation in Lithographically Textured Molybdenum Disulfide

1986 ◽  
Vol 82 ◽  
Author(s):  
C. B. Roxlo ◽  
H. W. Deckman ◽  
J. H. Dunsmuir ◽  
A. F. Ruppert ◽  
R. R. Chianelli
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Molybdenum Disulfide ◽  
Layered Structure ◽  
Single Layer ◽  
Chemical Treatments ◽  
Transmission Electron ◽  
Surface Disorder ◽  
Edge Surface

ABSTRACTLithographic techniques have been used to prepare transmission electron microscopy samples of MoS2, allowing examination of the edge surface with single-layer resolution. We observe that these surfaces are easily disordered by chemical treatments common in the catalysis industry. In some cases treatment in H2/H2S leads to an exfoliation of the layered structure, a process which can be observed as it occurs in the microscope.

scholarly journals Ultrastructural Features of Gold Nanoparticles Interaction with HepG2 and HEK293 Cells in Monolayer and Spheroids

Nanomaterials ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 2040 ◽  
Author(s):  
Boris Chelobanov ◽  
Julia Poletaeva ◽  
Anna Epanchintseva ◽  
Anastasiya Tupitsyna ◽  
Inna Pyshnaya ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Culture Medium ◽  
Hek293 Cells ◽  
Hydrodynamic Diameter ◽  
Multicellular Spheroids ◽  
Net Charge ◽  
Transmission Electron ◽  
Basal Plasma Membrane ◽  
Basal Plasma ◽  
Human Embryo Kidney

Use of multicellular spheroids in studies of nanoparticles (NPs) has increased in the last decade, however details of NPs interaction with spheroids are poorly known. We synthesized AuNPs (12.0 ± 0.1 nm in diameter, transmission electron microscopy (TEM data) and covered them with bovine serum albumin (BSA) and polyethyleneimine (PEI). Values of hydrodynamic diameter were 17.4 ± 0.4; 35.9 ± 0.5 and ±125.9 ± 2.8 nm for AuNPs, AuBSA-NPs and AuPEI-NPs, and Z-potential (net charge) values were −33.6 ± 2.0; −35.7 ± 1.8 and 39.9 ± 1.3 mV, respectively. Spheroids of human hepatocarcinoma (HepG2) and human embryo kidney (HEK293) cells (Corning ® spheroid microplates CLS4515-5EA), and monolayers of these cell lines were incubated with all NPs for 15 min–4 h, and fixed in 4% paraformaldehyde solution. Samples were examined using transmission and scanning electron microscopy. HepG2 and HEK2893 spheroids showed tissue-specific features and contacted with culture medium by basal plasma membrane of the cells. HepG2 cells both in monolayer and spheroids did not uptake of the AuNPs, while AuBSA-NPs and AuPEI-NPs readily penetrated these cells. All studied NPs penetrated HEK293 cells in both monolayer and spheroids. Thus, two different cell cultures maintained a type of the interaction with NPs in monolayer and spheroid forms, which not depended on NPs Z-potential and size.

Observations of Germinating Lychnis Alba Pollen

1971 ◽  
Vol 29 ◽  
pp. 348-349
Author(s):  
Richard E. Crang ◽  
Michael A. Millay
Keyword(s):  
Electron Microscopy ◽  
Pollen Tube ◽  
Liquid Culture ◽  
Culture Medium ◽  
Tube Wall ◽  
Pollen Grains ◽  
Pharbitis Nil ◽  
Liquid Culture Medium ◽  
Transmission Electron ◽  
Pollen Tube Wall

The exine surface of Lychnis alba pollen grains is ornamented with spines and pits (Fig. 1) that are variable both in size and number. No relationship appears to exist between the relative nature of these surface features as observed by means of scanning electron microscopy (SEM) and germination potentials of the pollen. The protrusion of cytoplasm at the apertures is a common phenomenon as the grains become hydrated when placed in liquid culture medium. As swelling of the apertures occurs, the aperturate opercula, or pore plates, may be lifted to the terminal surface but frequently are displaced to one side where they become embedded in the pollen tube wall (Fig.2). Although all apertures may protrude, only a single pollen tube will normally form from each grain. The composition of the opercula appear similar to the exine in transmission electron microscopy (TEM) preparations, but is less dense than the exine when observed in SEM preparations, as indicated by surface folds suggestive of a soft composition. There is no structural evidence that enzyme degradations of the exine at germination sites is required for emergence of the pollen tube, although such may be the case when pollen germinates on the style as indicated in SEM observations of Pharbitis nil pollen.

Effect of serum on the mitochondrial active area on developmental days 1 to 4 in in vitro-produced bovine embryos

Zygote ◽  
2011 ◽  
Vol 19 (4) ◽  
pp. 297-306 ◽  
Author(s):  
M. Crocco ◽  
R.H. Alberio ◽  
L. Lauria ◽  
M.I. Mariano
Keyword(s):  
Electron Microscopy ◽  
Culture Medium ◽  
Morphological Changes ◽  
Mitochondrial Dynamics ◽  
Developmental Changes ◽  
Bovine Embryos ◽  
Functional Changes ◽  
Transmission Electron ◽  
Subcellular Level

SummaryCertain morphological changes at the subcellular level caused by the current techniques for in vitro embryo production seem to affect mitochondria. Many of these, including dysfunctional changes, have been associated with the presence of serum in the culture medium. Thus, the aim of the present work was to assess the mitochondrial dynamics occurring in embryos during the first 4 days of development, in order to analyze the most appropriate time for adding the serum. We used transmission electron microscopy (TEM) micrographs to calculate the embryo area occupied by the different morphological types of mitochondria, and analyzed them with Image Pro Plus analyzer. The results showed hooded mitochondria as the most representative type in 1- to 4-day-old embryos. Swollen, on-fusion, orthodox and vacuolated types were also present. When analyzed in embryos cultured without serum, the dynamics of the different mitochondrial types appeared to be similar, a fact that may provide evidence that the developmental changes control the mitochondrial dynamics, and that swollen mitochondria may not be completely inactive. In contrast, in culture medium supplemented with serum from estrous cows, we observed an increased area of hooded mitochondria by developmental day 4, a fact that may indicate an increased production of energy compared with previous days. According to these results, the bovine serum added to the culture medium seems not to be responsible for the functional changes in mitochondria.

Neutrophils injure cultured skeletal myotubes

2001 ◽  
Vol 281 (1) ◽  
pp. C335-C341 ◽  
Author(s):  
Francis X. Pizza ◽  
Thomas J. McLoughlin ◽  
Stephen J. McGregor ◽  
Edward P. Calomeni ◽  
William T. Gunning
Keyword(s):  
Electron Microscopy ◽  
Membrane Rupture ◽  
Cytoplasmic Vacuoles ◽  
Transmission Electron ◽  
Human Myotubes ◽  
Membrane Blebs ◽  
Blood Neutrophils ◽  
Skeletal Myotubes

The purpose of the study was to test the hypothesis that neutrophils can injure cultured skeletal myotubes. Human myotubes were grown and then cultured with human blood neutrophils. Myotube injury was quantitatively and qualitatively determined using a cytotoxicity (51Cr) assay and electron microscopy, respectively. For the 51Cr assay, neutrophils, under non-in vitro-stimulated and N-formylmethionyl-leucyl-phenylalanine (FMLP)-stimulated conditions, were cultured with myotubes at effector-to-target cell (E:T) ratios of 10, 30, and 50 for 6 h. Statistical analyses revealed that myotube injury was proportional to the E:T ratio and was greater in FMLP-stimulated conditions relative to non-in vitro-stimulated conditions. Transmission electron microscopy, using lanthanum as an extracellular tracer, revealed in cocultures a diffuse appearance of lanthanum in the cytoplasm of myotubes and a localized appearance within cytoplasmic vacuoles of myotubes. These observations and their absence in control cultures (myotubes only) suggest that neutrophils caused membrane rupture and increased myotube endocytosis, respectively. Myotube membrane blebs were prevalent in scanning and transmission electron micrographs of cultures consisting of neutrophils and myotubes (E:T ratio of 5) and were absent in control cultures. These data support the hypothesis that neutrophils can injure skeletal myotubes in vitro and may indicate that neutrophils exacerbate muscle injury and/or delay muscle regeneration in vivo.

scholarly journals Preparation of large-scale digitization samples for automated electron microscopy of tissue and cell ultrastructure

2021 ◽  
Author(s):  
Carsten Dittmayer ◽  
Hans-Hilmar Goebel ◽  
Frank L. Heppner ◽  
Werner Stenzel ◽  
Sebastian Bachmann
Keyword(s):  
Electron Microscopy ◽  
Large Scale ◽  
Cell Ultrastructure ◽  
Throughput Gain ◽  
Transmission Electron ◽  
Manual Selection ◽  
Diagnostic Samples ◽  
Scanning Em ◽  
Selection Of ◽  
Tissue Ultrastructure

AbstractManual selection of targets in experimental or diagnostic samples by transmission electron microscopy (TEM), based on single overview and detail micrographs, has been time- consuming and susceptible to bias. Substantial information and throughput gain may now be achieved by automated acquisition of virtually all structures in a given EM section. Resulting datasets allow convenient pan-and-zoom examination of tissue ultrastructure with preserved microanatomical orientation. The technique is, however, critically sensitive to artifacts in sample preparation. We therefore established a methodology to prepare large-scale digitization samples (LDS) designed to acquire entire sections free of obscuring flaws. For evaluation, we highlight the supreme performance of scanning EM in transmission mode compared to other EM technology. The use of LDS will substantially facilitate access to EM data for a broad range of applications.

scholarly journals Effects of Jiawei Shaoyao-Gancao Decoction and Its Drug-Containing Serum on Proliferation, Apoptosis, and Ultrastructure of Human Adenomyosis Foci Cells

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Yu-yan Zeng ◽  
Kun-yin Li
Keyword(s):  
Electron Microscopy ◽  
Cell Proliferation ◽  
Cell Apoptosis ◽  
Chromatin Condensation ◽  
Primary Cultures ◽  
Cell Ultrastructure ◽  
Dependent Manner ◽  
Transmission Electron ◽  
Dose Dependent ◽  
Insight Into

Objective. The present study aimed to investigate the effects of Jiawei Shaoyao-Gancao Decoction (JSGD) and its drug-containing serum (CDS) on the proliferation, apoptosis, and ultrastructure of human adenomyosis foci cells. Methods. Primary cultures of human adenomyosis foci cells were prepared from hard uterine lesions of adenomyosis patients. The cells were treated with JSGD (10 and 20 mg/ml), CDS, and mifepristone (MIF) for 24 or 48 h. Cell proliferation was detected using CCK-8 assay, cell apoptosis was measured by flow cytometry, and the cell ultrastructure was observed by transmission electron microscopy (TEM). Results. JSGD and CDS significantly induced cell apoptosis and inhibited cell proliferation for 24 h or 48 h, in which the effects of JSGD were in a dose-dependent manner. The effect of CDS for 24 h was higher than that of CDS for 48 h. Moreover, JSGD and CDS treatments induced marked apoptosis in adenomyosis foci cells, characterized by nucleus chromatin, condensation, fragmentation, mitochondria and endoplasmic swelling, and autophagy-lysosome. Conclusions. JSGD and CDS can suppress proliferation and induce apoptosis in adenomyosis foci cells, through altering their ultrastructure. The results provided support for JSGD and CDS in the treatment of adenomyosis and gained further insight into the effect of this prescription.

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