Oxyhemoglobin-induced apoptosis in cultured endothelial cells

Object. Oxyhemoglobin (OxyHb) is one of the most important spasmogens for cerebral vasospasm that follows aneurysmal subarachnoid hemorrhage. The cytotoxic effect of OxyHb has been documented in endothelial and smooth-muscle cells; however, the pattern of cell death—necrosis or apoptosis—as the final stage of cell damage has not been demonstrated. This study was undertaken to determine if OxyHb induces apoptotic changes in cultured bovine aortic endothelial cells.Methods. Confluent bovine aortic endothelial cells were treated with OxyHb in a concentration- and time-dependent manner. Cell density was assayed by counting the number of cells that attached to culture dishes after exposure to OxyHb. To identify apoptotic changes, the investigators used three specific methods: DNA fragmentation (electrophoreses), the apoptotic body (transmission electron microscopy), and cleavage of poly (adenosine diphosphate ribose) polymerase (PARP [Western blotting]).Conclusions. Oxyhemoglobin decreased cell density in a concentration- and time-dependent manner. Analysis of DNA showed a pattern of internucleosomal cleavage characteristic of apoptosis (DNA ladder). Transmission electron microscopy demonstrated condensation of nuclei and apoptotic bodies in OxyHb-treated endothelial cells. Western blotting with the PARP antibody revealed that the 116-kD PARP was cleaved to the 85-kD apoptosis-related fragment. These results for the first time demonstrated that the OxyHb induces apoptosis in cultured endothelial cells.

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Analysis of brain biocompatibility of drug-releasing biodegradable microspheres by scanning and transmission electron microscopy

Journal of Neurosurgery ◽

10.3171/jns.2001.95.3.0489 ◽

2001 ◽

Vol 95 (3) ◽

pp. 489-494 ◽

Cited By ~ 30

Author(s):

Joëlle Veziers ◽

Maurice Lesourd ◽

Christophe Jollivet ◽

Claudia Montero-Menei ◽

Jean-Pierre Benoit ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Brain Tissue ◽

Neurotrophic Factors ◽

Rat Striatum ◽

Inert Material ◽

Biodegradable Microspheres ◽

Content Type ◽

Transmission Electron ◽

Fine Print

Object. Stereotactically guided implantation of biodegradable microspheres is a promising strategy for delivery of neurotrophic factors in a precise and spatially defined brain area. The goal in this study was to show the biocompatibility of poly(D,L,lactide-co-glycolide) microspheres with brain tissue at the ultrastructural level and to analyze the three-dimensional (3D) ultrastructure after intrastriatal implantation of these microparticles. Methods. Scanning and transmission electron microscopy were used to study the microspheres and their environment after implantation in an inert material (gelatin) and in the rat striatum. Observations were made at different time periods, ranging from 24 hours to 2 months postimplantation. Conclusions. The progressive degradation of the microspheres, with vacuolization, deformation, and shrinkage, was well visualized. This degradation was identical in microspheres implanted in the inert material and in the rat brain tissue, independent of the presence of macrophages. The studies preformed in the striatum permitted the authors to demonstrate the structural integrity of axons in contact with microspheres, confirming the biocompatibility of the polymer. Furthermore, scanning electron microscopy showed the preservation of the 3D ultrastructure of the striatum around the microparticles. These microparticles, which can be stereotactically implanted in functional areas of the brain and can release neurotrophic factors, could represent, for some indications, an alternative to gene therapy.

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Human neonatal hydrocephalus

Journal of Neurosurgery ◽

10.3171/jns.1985.63.1.0056 ◽

1985 ◽

Vol 63 (1) ◽

pp. 56-63 ◽

Cited By ~ 30

Author(s):

Marc R. Del Bigio ◽

J. Edward Bruni ◽

H. Derek Fewer

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Ependymal Cells ◽

Foramen Of Monro ◽

Content Type ◽

Axonal Pathology ◽

Transmission Electron ◽

Cell Processes ◽

Junctional Complexes ◽

Fine Print

✓ An infant of 43 weeks gestational age with severe congenital hydrocephalus was operated on for removal of a subependymal astrocytoma in the region of the foramen of Monro. A biopsy of periventricular tissue was taken from the lateral ventricle for examination by scanning and transmission electron microscopy. The ependyma was largely denuded, with glial cell processes forming most of the ventricular lining. Many of the attenuated ependymal cells, however, had intact junctional complexes at areas of contact with other ependymal cells. Club-shaped unipolar cells, believed to be a previously undescribed form of immature ependymal cells, were found in the ventricular lining. Cerebrospinal fluid edema was present in the neuropil up to 60 µm from the ventricular lumen, but there was no obvious axonal pathology in the tissues examined.

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Antitumor Potential of Green Synthesized ZnONPs Using Root Extract of Withania somnifera against Human Breast Cancer Cell Line

Separations ◽

10.3390/separations8010008 ◽

2021 ◽

Vol 8 (1) ◽

pp. 8

Author(s):

Kollur Shiva Prasad ◽

Shashanka K Prasad ◽

Ravindra Veerapur ◽

Ghada Lamraoui ◽

Ashwini Prasad ◽

...

Keyword(s):

Breast Cancer ◽

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Cell Line ◽

Withania Somnifera ◽

Root Extract ◽

Dependent Manner ◽

Sem Images ◽

Xrd Pattern ◽

Transmission Electron

Herein we report the synthesis of zinc oxide nanoparticles (ZnONPs) using Withania somnifera root extract (WSE) as an effective chelating agent. The microscopic techniques viz., X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and selected area electron diffraction (SAED) were employed to analyze the as-obtained ZnONPs. The crystalline planes observed from the XRD pattern agrees with the hexagonal wurtzite structure of the as-prepared ZnONPs. The aggregations and agglomerations observed in the SEM images indicated that the size of the as-prepared ZnONPs was between 30 and 43 nm. The interplanar distance between the lattice fringes observed in the HRTEM image was found to be 0.253 nm, which is in good agreement with the (100) plane obtained in the XRD pattern. Furthermore, the anti-breast cancer cytotoxic evaluation was carried out using the MCF-7 cell line, and the results showed significant cytotoxic effects in a dose-dependent manner.

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Structural and analytical studies of the silicified macrohairs from the lemma of the grass Phalaris canariensis L

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1984.0075 ◽

1984 ◽

Vol 222 (1229) ◽

pp. 427-438 ◽

Cited By ~ 40

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Silica Particles ◽

Time Dependent ◽

Energy Dispersive ◽

X Ray ◽

Analytical Studies ◽

Transmission Electron ◽

Cellular Control ◽

Phalaris Canariensis

Silicified macrohairs from mature and immature lemmas of the grass Phalaris canariensis L. have been studied by scanning (s.e.m.) and transmission electron microscopy (t.e.m.) and energy dispersive X-ray analysis (e.d.X.a.) at various times after emergence of the inflorescence. Within the macrohairs a variety of morphologies of silica particles was observed. E.d.X.a. revealed the time-dependent concentrations in the macrohairs of the elements K, Cl, P, and S, in addition to Si. Much lower levels of these elements were found in highly silicified mature macrohairs than in the immature macrohairs. It is proposed that the hairs are silicified under strict cellular control.

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In VitroEffects of Novel Ruthenium Complexes in Neospora caninum and Toxoplasma gondii Tachyzoites

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02446-12 ◽

2013 ◽

Vol 57 (11) ◽

pp. 5747-5754 ◽

Cited By ~ 19

Author(s):

Fabienne Barna ◽

Karim Debache ◽

Carsten A. Vock ◽

Tatiana Küster ◽

Andrew Hemphill

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Toxoplasma Gondii ◽

Neospora Caninum ◽

Ruthenium Complexes ◽

Term Treatment ◽

Content Type ◽

Transmission Electron ◽

Long Term Treatment

ABSTRACTUpon the screening of 16 antiproliferative compounds againstToxoplasma gondiiandNeospora caninum, two hydrolytically stable ruthenium complexes (compounds 16 and 18) exhibited 50% inhibitory concentrations of 18.7 and 41.1 nM (T. gondii) and 6.7 and 11.3 nM (N. caninum). To achieve parasiticidal activity with compound 16, long-term treatment (22 to 27 days at 80 to 160 nM) was required. Transmission electron microscopy demonstrated the rapid impact on and ultrastructural alterations in both parasites. These preliminary findings suggest that the potential of ruthenium-based compounds should thus be further exploited.

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Histochemical Studies On The In Vitro 5-HT Uptake In Endothelial Cells

10.1055/s-0038-1653227 ◽

1981 ◽

Author(s):

T Kjellström ◽

H Ahlman ◽

F Dahlström ◽

G Hansson ◽

B Stenberg ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Endothelial Cells ◽

Factor Viii ◽

Serotonin Uptake ◽

Adult Rats ◽

Pulmonary Endothelial Cells ◽

Transmission Electron ◽

5 Ht Uptake

Previous studies have shown that 5-HT is rapidly taken up by the endothelial cells and some investigations also suggested that serotonin is metabolized within these cells. In earlier studies on rat-lungs using a fluorescence histo- chemical method according to Hillarp - Falk we demonstrated that 5-HT was accumulated within the mast cells. Using this technique we could not demonstrate any specific uptake in the pulmonary endothelial cells. It was the purpose of the present investigation to further study the 5-HT uptake by isolated pulmonary endothelial cells.Methods Cells from the vascular intima of the pulmonary artery in adult rats were grown in a growth medium containing FCS. The endothelial nature of these cells was demonstrated using transmission electron microscopy and factor VIII analysis. Confluent endothelial cells were incubated with 5-HT and the cellular uptake was studied with fluorescence microscopy according to the Hillarp - Falk procedure.Results The endothelial cells were identified by the presence of Weibel-Palade bodies using transmission electron microscopy and the immunofluorescent demonstration of cellular factor VIII antigen. Cells not exposed to serotonin had no specific 5-HT fluorescense. After incubation with 5-HT at different concentrations there was a progressive uptake of the amine within the cells.Conclusions This study confirms previous reports on the specific serotonin uptake in endothelial cells. The Hillarp-Falk procedure seems suitable for further studies of serotonin uptake in cultured endothelial cells.

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Chlorpromazine modulates the morphological macro- and microstructure of endothelial cells

AJP Cell Physiology ◽

10.1152/ajpcell.2000.278.5.c873 ◽

2000 ◽

Vol 278 (5) ◽

pp. C873-C878 ◽

Cited By ~ 15

Author(s):

I. S. Hueck ◽

H. G. Hollweg ◽

G. W. Schmid-Schönbein ◽

G. M. Artmann

Keyword(s):

Endothelial Cells ◽

Antipsychotic Agent ◽

Membrane Curvature ◽

Phospholipid Bilayer ◽

Aortic Endothelial Cells ◽

Bovine Aortic Endothelial Cells ◽

Cellular Attachment ◽

Transmission Electron ◽

Membrane Adhesion ◽

Membrane Bending

Chlorpromazine (CP), an amphipathic, antipsychotic agent, causes concave membrane bending in red blood cells with formation of stomatocytic shapes by modulation of the phospholipid bilayer. This study was designed to investigate the effects of CP on the shape of bovine aortic endothelial cells (BAEC) and their membranes in confluent monolayers with phase-contrast and transmission electron microscopy. Exposure of BAECs to nanomolar levels of CP leads to membrane curvature changes. With increasing CP concentrations, the membrane assumed a shape with enhanced numbers of intracellular caveolae and projection of pseudopodia at all junctions. At higher CP concentrations (up to 150 μM), the endothelial cells assumed almost spherical shapes. The evidence suggests that CP may affect lipid bilayer bending of BAECs in analogy with previous observations on erythrocytes, supporting the formation of caveolae and pseudopodia in BAECs due to the induction of concave membrane bending, as well as an effect on endothelial cell membrane adhesion at higher CP concentrations with loss of cellular attachment at junctions.

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Antimicrobial Properties of a Chitosan Dextran-Based Hydrogel for Surgical Use

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.05463-11 ◽

2011 ◽

Vol 56 (1) ◽

pp. 280-287 ◽

Cited By ~ 80

Author(s):

Manal A. Aziz ◽

Jaydee D. Cabral ◽

Heather J. L. Brooks ◽

Stephen C. Moratti ◽

Lyall R. Hanton

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Bacterial Species ◽

Antimicrobial Properties ◽

Sinus Surgery ◽

Peptide Bonds ◽

Content Type ◽

E Coli ◽

Transmission Electron

ABSTRACTA chitosan dextran-based (CD) hydrogel, developed for use in endoscopic sinus surgery, was tested for antimicrobial activityin vitroagainst a range of pathogenic microorganisms. The microdilution technique was used to determine minimum inhibitory, minimum bactericidal, and minimum fungicidal concentrations. In addition, the time-kill efficacy of CD hydrogel was determined for two bacterial species. Scanning and transmission electron microscopy were carried out to elucidate the antimicrobial mechanism of this compound. CD hydrogel was found to be effective againstStaphylococcus aureus,Streptococcus pyogenes,Escherichia coli, andClostridium perfringensat its surgical concentration of 50,000 mg/liter. Minimum bactericidal concentrations ranged from 2,000 to 50,000 mg/liter. Dextran aldehyde (DA) was found to be the antimicrobial component of the CD hydrogel with MBC ranging from 2,000 to 32,000 mg/liter.S. aureusappeared to be killed at a slightly faster rate thanE. coli. Candida albicansandPseudomonas aeruginosawere more resistant to CD hydrogel and DA. Scanning and transmission electron microscopy ofE. coliandS. aureusincubated with CD hydrogel and DA alone revealed morphological damage, disrupted cell walls, and loss of cytosolic contents, compatible with the proposed mode of action involving binding to cell wall proteins and disruption of peptide bonds. Motility and chemotaxis tests showedE. colito be inhibited when incubated with DA. The antibacterial activity of CD hydrogel may make it a useful postsurgical aid at other body sites, especially where there is a risk of Gram-positive infections.

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