scholarly journals Effect of One Year of Cryopreservation on the Activity of Lysosomal Hydrolases from EBV-Transformed Lymphocytes

2011 ◽  
Vol 2011 ◽  
pp. 1-5
Author(s):  
A. S. de Mello ◽  
F. B. Mendes ◽  
K. Michelin-Tireli ◽  
M. V. Camelier ◽  
J. C. Coelho
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Cell Transformation ◽  
Morphological Changes ◽  
Lysosomal Storage ◽  
Lysosomal Hydrolases ◽  
Cell Bank ◽  
Transmission Electron ◽  
Infected Cells ◽  
One Year

Background. The Epstein-Barr virus (EBV) was used as an agent of B lymphocyte proliferation for subsequent diagnosis of lysosomal storage disease. Due to the constant handling of long-preserved samples in our cell bank, we decided to observe the behavior and then compare cultured and frozen samples for at least one year's cryopreservation.Methods. Twenty-five samples from healthy individuals were used to assess the possible changes in activity of enzymesβ-galactosidase,β-glucosidase,α-iduronidase,α-galactosidase, andα-glucosidase. Transmission electron microscopy was used to confirm cell transformation of B lymphocytes into EBV-infected cells, generating lymphoblastoid cell lines.Results. Transmission electron microscopy findings confirmed previous reports in the literature that is, significant and evident morphological changes in the nucleus occur after day 12 and the consequent cell transformation into EBV-infected cells. After thawing and subsequent treatment with the five enzymes utilized, we observed no significant changes in samples cryopreserved for more than one year, as compared to samples cultured for 12 days.

scholarly journals Cytochemical localization of calcium and Ca2+,Mg2(+)-adenosine triphosphatase in colchicine-altered rat incisor ameloblasts.

1990 ◽  
Vol 38 (10) ◽  
pp. 1469-1478 ◽  
Author(s):  
D R Eisenmann ◽  
A H Salama ◽  
A M Zaki ◽  
S H Ashrafi
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Adenosine Triphosphatase ◽  
Morphological Changes ◽  
Rat Incisor ◽  
Cytochemical Localization ◽  
Early Maturation ◽  
Transmission Electron ◽  
Maturation Stages ◽  
Secretory Transport

Colchicine is known to affect secretory, transport, and degradative functions of ameloblasts. The effects of colchicine on membrane-associated calcium and Ca2+,Mg2(+)-ATPase in secretory and maturation ameloblasts were investigated cytochemically. The pyroantimonate (PPA) method was used for localizing calcium and a modified Wachstein-Meisel medium was used to localize Ca2+,Mg2(+)-ATPase. Sections representing secretory and early maturation stages were examined by transmission electron microscopy. Morphological changes induced by colchicine included dislocated organelles and other well-established reactions to such anti-microtubule drugs. Calcium pyroantimonate (Ca-PA) deposits in most ameloblast types were markedly reduced, with the greater reduction occurring in those cells more severely altered morphologically. However, the cell membranes of both control and experimental smooth-ended maturation ameloblasts were essentially devoid of Ca-PA. The normal distribution and intensity of Ca2+,Mg2(+)-ATPase was not affected by colchicine. Because the observed reduction of membrane-associated calcium is apparently not mediated by Ca2+,Mg2(+)-ATPase in this case, other aspects of the calcium regulating system of ameloblasts are apparently targeted by colchicine.

scholarly journals Polymeric Self-Assemblies Based on tetra-ortho-Substituted Azobenzene as Visible Light Responsive Nanocarriers

Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2060
Author(s):  
Alejandro Roche ◽  
Luis Oriol ◽  
Rosa M. Tejedor ◽  
Milagros Piñol
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Diblock Copolymers ◽  
Uv Light ◽  
Morphological Changes ◽  
Nile Red ◽  
Green Light ◽  
Light Irradiation ◽  
Transmission Electron ◽  
Amphiphilic Diblock Copolymers

Most of reported polymeric light-responsive nanocarriers make use of UV light to trigger morphological changes and the subsequent release of encapsulated cargoes. Moving from UV- to visible-responsive units is interesting for the potential biomedical applications of these materials. Herein we report the synthesis by ring opening polymerization (ROP) of a series of amphiphilic diblock copolymers, into which either UV or visible responsive azobenzenes have been introduced via copper(I) catalyzed azide-alkyne cycloaddition (CuAAC). These copolymers are able to self-assemble into spherical micelles or vesicles when dispersed in water. The study of the response of the self-assemblies upon UV (365 nm) or visible (530 or 625 nm) light irradiation has been studied by Transmission Electron Microscopy (TEM), Cryogenic Transmission Electron Microscopy (Cryo-TEM), and Dynamic Light Scattering (DLS) studies. Encapsulation of Nile Red, in micelles and vesicles, and Rhodamine B, in vesicles, and its light-stimulated release has been studied by fluorescence spectroscopy and confocal microscopy. Appreciable morphological changes have been induced with green light, and the subsequent release of encapsulated cargoes upon green light irradiation has been confirmed.

Morphological changes of poly(tetrafluoroethylene) by heat treatment on NaCl

1993 ◽  
Vol 8 (11) ◽  
pp. 2942-2947 ◽  
Author(s):  
Sadaatsu Yamaguchi ◽  
Masaki Tsuji
Keyword(s):  
Electron Microscopy ◽  
Heat Treatment ◽  
Transmission Electron Microscopy ◽  
Morphological Changes ◽  
Dark Field ◽  
Exothermic Peak ◽  
Lateral Side ◽  
Cooling Process ◽  
Transmission Electron ◽  
Heat Treated

Fine granules of poly(tetrafluoroethylene) (PTFE) were heat-treated/annealed on NaCl near its melting temperature (Tm) and/or at a temperature (Tc) between upper and lower feet of the exothermic peak in the DSC cooling process from Tm. Morphological changes of the granules were examined in the bright- and dark-field modes by transmission electron microscopy. When the granules were heat-treated near Tm, microfibrils of 20–30 nm in width and fibrils of 70–120 nm in width came out of the granules. The microfibrils were also observed in the fibrils. The microfibrils formed by heat treatment near Tm seemed to be identified as microfibrils of 20–30 nm in width which were recognized outside the granules annealed at Tc. It is expected that such a microfibril will grow to be a band in the band structure observed on the surface of bulk PTFE. Since the 0015 dark-field images showed that the PTFE chains in such microfibrils and fibrils are set perpendicular to their fibril axis, the chains should fold back and forth repeatedly at both lateral side-surfaces of the microfibrils and fibrils.

scholarly journals Morphological structure of rat epiphysis exposed to electromagnetic radiation from communication devices

2019 ◽  
Vol 95 (10) ◽  
pp. 977-979
Author(s):  
Svetlana G. Yashchenko ◽  
S. Yu. Rybalko
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Pineal Gland ◽  
Electromagnetic Radiation ◽  
Mobile Phones ◽  
Morphological Changes ◽  
The Body ◽  
Transmission Electron ◽  
Communication Devices ◽  
Rat Pineal Gland

Pineal gland is one of the most important components of homeostasis - the supporting system of the body. It participates in the launch of stress responses, restriction of their development, prevention of adverse effects on the body. There was proved an impact of electromagnetic radiation on the epiphysis. However, morphological changes in the epiphysis under exposure to electromagnetic radiation of modern communication devices are studied not sufficiently. For the time present the population is daily exposed to electromagnetic radiation, including local irradiation on the brain. These date determined the task of this research - the study of the structure of rat pineal gland under the exposure to electromagnetic radiation from personal computers and mobile phones. These date determined the task of this research - the study of the structure of rat pineal gland under the exposure to electromagnetic radiation from personal computers and mobile phones. Performed transmission electron microscopy revealed signs of degeneration of dark and light pinealocytes. These signs were manifested in the development of a complex of general and specific morphological changes. There was revealed the appearance of signs of aging and depletion transmission electron microscopy both in light and dark pinealocytes. These signs were manifested in the accumulation of lipofuscin granules and electron-dense "brain sand", the disappearance of nucleoli, cytoplasm vacuolization and mitochondrial cristae enlightenment.

scholarly journals Differential accumulation of storage bodies with aging defines discrete subsets of microglia in the healthy brain

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Jeremy Carlos Burns ◽  
Bunny Cotleur ◽  
Dirk M Walther ◽  
Bekim Bajrami ◽  
Stephen J Rubino ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Cell Death ◽  
Molecular Level ◽  
Adult Life ◽  
Lysosomal Storage ◽  
Lysosomal Function ◽  
Transmission Electron ◽  
Related Proteins ◽  
Storage Disorders

To date, microglia subsets in the healthy CNS have not been identified. Utilizing autofluorescence (AF) as a discriminating parameter, we identified two novel microglia subsets in both mice and non-human primates, termed autofluorescence-positive (AF+) and negative (AF−). While their proportion remained constant throughout most adult life, the AF signal linearly and specifically increased in AF+ microglia with age and correlated with a commensurate increase in size and complexity of lysosomal storage bodies, as detected by transmission electron microscopy and LAMP1 levels. Post-depletion repopulation kinetics revealed AF− cells as likely precursors of AF+ microglia. At the molecular level, the proteome of AF+ microglia showed overrepresentation of endolysosomal, autophagic, catabolic, and mTOR-related proteins. Mimicking the effect of advanced aging, genetic disruption of lysosomal function accelerated the accumulation of storage bodies in AF+ cells and led to impaired microglia physiology and cell death, suggestive of a mechanistic convergence between aging and lysosomal storage disorders.

Transmission Electron Microscopy Study of Listeria monocytogenes Treated with Nisin in Combination with either Grape Seed or Green Tea Extract

2008 ◽  
Vol 71 (10) ◽  
pp. 2105-2109 ◽  
Author(s):  
T. SIVAROOBAN ◽  
N. S. HETTIARACHCHY ◽  
M. G. JOHNSON
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Listeria Monocytogenes ◽  
Green Tea ◽  
Morphological Changes ◽  
Grape Seed ◽  
Green Tea Extract ◽  
Transmission Electron ◽  
Phenolic Constituents ◽  
Tea Extract

The objective of this study was to use transmission electron microscopy to investigate the morphological changes that occurred in Listeria monocytogenes cells treated with grape seed extract (GSE), green tea extract (GTE), nisin, and combinations of nisin with either GSE or GTE. The test solutions were prepared with (i) 1% GSE, 1% GTE, 6,400 IU of nisin, and the combination of these dilutions with nisin or with (ii) the pure major phenolic constituents of GSE (0.02% epicatechin plus 0.02% catechin) or GTE (0.02% epicatechin plus 0.02% caffeic acid) and their combinations with 6,400 IU of nisin in tryptic soy broth with 0.6% yeast extract (TSBYE). Test solutions were inoculated with L. monocytogenes at approximately 106 CFU/ml and incubated for 3 or 24 h at 37°C. After 3 h of incubation, cells were harvested and evaluated under a transmission electron microscope (JEOL-100 CX) operating at 80 kV (50,000×). Microscopic examination revealed an altered cell membrane and condensed cytoplasm when L. monocytogenes cells were exposed to a combination of nisin with either GSE or GTE or to pure compounds of the major phenolic constituents in combination. After 24 h of incubation at 37°C, the combinations of nisin with GSE and nisin with GTE reduced the L. monocytogenes population to undetectable levels and 3.7 log CFU/ml, respectively. These observations indicate that the combination of nisin with either GSE or GTE had a synergistic effect, and the combinations of nisin with the major phenolic constituents were most likely associated with the L. monocytogenes cell damage during inactivation in TSBYE at 37°C.

Plasmodium falciparum: regional differences in lectin and cationized ferritin binding to the surface of the malaria-infected human erythrocyte

Parasitology ◽  
1986 ◽  
Vol 93 (1) ◽  
pp. 17-32 ◽  
Author(s):  
I. W. Sherman ◽  
Jane R. T. Greenan
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Plasmodium Falciparum ◽  
Uniform Distribution ◽  
Lectin Binding ◽  
Red Cells ◽  
Cationized Ferritin ◽  
Transmission Electron ◽  
Erythrocyte Surface ◽  
Infected Cells

SUMMARYThe distribution of anionic residues on the surface of erythrocytes infected withPlasmodium falciparumwas studied using cationized ferritin (CF) and transmission electron microscopy. CF staining of uninfected erythrocytes or erythrocytes infected with a knobless variant resulted in a dense and uniform distribution of ferritin particles; however, when red cells infected with a knob-inducing variant were exposed to CF, aggregates of ferritin particles were observed in the region of membrane elevation. Lectin binding to the erythrocyte surface was visualized by transmission electron microscopy using ferritin-conjugated lectins and lectin-fetuin-gold. No differences were observed in the lectin-binding patterns of malaria-infected or uninfected erythrocytes using WGA (wheat-germ agglutinin), RCA (ricin), andLimax flavuslectin. In distinct contrast to the uniform distribution of ferritin particles seen with these lectins was the appearance of clusters of ferritin-ConA over the knobby regions. Localized aggregates of ConA were not seen in knob-free areas or on the surface of red cells infected with a knobless variant. No significant differences were found in the agglutination reactions of normal and infected cells with theCancer antennariuslectin specific forO-acylated sialic acids.

scholarly journals Lithiation of multilayer Ni/NiO electrodes: criticality of nickel layer thicknesses on conversion reaction kinetics

2017 ◽  
Vol 19 (30) ◽  
pp. 20029-20039 ◽  
Author(s):  
Guennadi Evmenenko ◽  
Timothy T. Fister ◽  
D. Bruce Buchholz ◽  
Fernando C. Castro ◽  
Qianqian Li ◽  
...  
Keyword(s):  
Thin Film ◽  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Reaction Kinetics ◽  
Layer Thickness ◽  
Morphological Changes ◽  
Nickel Layer ◽  
X Ray ◽  
Transmission Electron ◽  
Buffer Layer Thickness

X-ray reflectivity and transmission electron microscopy (TEM) were used to characterize the morphological changes in thin film electrodes with alternating Ni and NiO layers during lithiation as a function of the Ni buffer layer thickness.

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