scholarly journals Theβ-SiC Nanowires (~100 nm) Induce Apoptosis via Oxidative Stress in Mouse Osteoblastic Cell Line MC3T3-E1

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Weili Xie ◽  
Qi Xie ◽  
Meishan Jin ◽  
Xiaoxiao Huang ◽  
Xiaodong Zhang ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Oxidative Dna Damage ◽  
Morphological Changes ◽  
Osteoblastic Cell ◽  
Osteoblastic Cell Line ◽  
Sic Nanowires ◽  
Tissue Replacement ◽  
Transmission Electron ◽  
First Time

Silicon carbide (SiC), a compound of silicon and carbon, with chemical formula SiC, the beta modification (β-SiC), with a zinc blende crystal structure (similar to diamond), is formed at temperature below1700∘C.β-SiC will be the most suitable ceramic material for the future hard tissue replacement, such as bone and tooth. Thein vitrocytotoxicity ofβ-SiC nanowires was investigated for the first time. Our results indicated that 100 nm long SiC nanowires could significantly induce the apoptosis in MC3T3-E1 cells, compared with 100 μm long SiC nanowires. And 100 nm long SiC nanowires increased oxidative stress in MC3T3-E1 cells, as determined by the concentrations of MDA (as a marker of lipid peroxidation) and 8-OHdG (indicator of oxidative DNA damage). Moreover, transmission electron microscopy (TEM) was performed to evaluate the morphological changes of MC3T3-E1 cells. After treatment with 100 nm long SiC nanowires, the mitochondria were swelled and disintegrated, and the production of ATP and the total oxygen uptake were also decreased significantly. Therefore,β-SiC nanowires may have limitations as medical material.

scholarly journals Contrasting effects of accumulation and tolerance characteristics in Arabidopsis thaliana under Cr(III) and Cr(VI) stress

2021 ◽  
Author(s):  
Yonghong Han ◽  
Guotao Ding ◽  
Peng Sun ◽  
Giuiying Li ◽  
Weihao Li
Keyword(s):  
Oxidative Stress ◽  
Arabidopsis Thaliana ◽  
Root Length ◽  
Morphological Changes ◽  
Antioxidant Systems ◽  
Inhibition Of Growth ◽  
Transmission Electron ◽  
Chromium Accumulation ◽  
First Time ◽  
Physiological And Biochemical

In this study, for the first time we investigated Cr(III) and Cr(VI) stress-induced physiological and biochemical responses in Arabidopsis thaliana . The capacity of A. thalian to accumulate Cr is closely related to the valence of chromium. Cr(VI) was more toxic than Cr(III) as indicated by chromium accumulation and growth inhibition. When the concentration of chromium is greater than 200μM, the root length and biomass of A. thaliana are reduced. But interestingly, Cr(III) at 200μM increased the root length and biomass of A. thaliana compared to the control. The transmission electron microscope shows that Cr(VI) can cause the chloroplasts damaged and the chlorophyll reduced more than Cr(III). The chloroplasts were filled the starch grains. An increase of lipid peroxidation in A. thaliana roots caused by Cr was measured, and this effect increases as the increasing Cr. It indicated that A. thaliana suffers from Cr-induced oxidative stress which resulted cell death in roots. To fight against oxidative stress, Ascorbate peroxidase and Glutathione reductase were activated by Cr in antioxidant defense. The inhibition of growth, the accumulation of chromium, the responses of antioxidant systems, and the ultra-morphological changes indicate that Cr(VI) was more toxic than Cr(III) .

Correlation Between Cellular Functions and Morphological Changes of Human Trophoblast in Vitro

1975 ◽  
Vol 33 ◽  
pp. 600-601
Author(s):  
John C. Garancis ◽  
Robert O. Hussa ◽  
Michael T. Story ◽  
Donald Yorde ◽  
Roland A. Pattillo
Keyword(s):  
Electron Microscopy ◽  
Cellular Proliferation ◽  
Morphological Changes ◽  
Culture Fluid ◽  
Cellular Functions ◽  
Human Trophoblast ◽  
Transmission Electron ◽  
Marked Activity ◽  
Malignant Trophoblast

Human malignant trophoblast cells in continuous culture were incubated for 3 days in medium containing 1 mM N6-O2'-dibutyryl cyclic adenosine 3':5'-monophosphate (dibutyryl cyclic AMP) and 1 mM theophylline. The culture fluid was replenished daily. Stimulated cultures secreted many times more chorionic gonadotropin and estrogens than did control cultures in the absence of increased cellular proliferation. Scanning electron microscopy revealed remarkable surface changes of stimulated cells. Control cells (not stimulated) were smooth or provided with varying numbers of microvilli (Fig. 1). The latter, usually, were short and thin. The surface features of stimulated cells were considerably different. There was marked increase of microvilli which appeared elongated and thick. Many cells were covered with confluent polypoid projections (Fig. 2). Transmission electron microscopy demonstrated marked activity of cytoplasmic organelles. Mitochondria were increased in number and size; some giant forms with numerous cristae were observed.

scholarly journals In vitro biological activity of Hydroclathrus clathratus and its use as an extracellular bioreductant for silver nanoparticle formation

2020 ◽  
Vol 9 (1) ◽  
pp. 416-428 ◽  
Author(s):  
Raghad R. Alzahrani ◽  
Manal M. Alkhulaifi ◽  
Nouf M. Al-Enazi
Keyword(s):  
Biological Activity ◽  
Unsaturated Fatty Acids ◽  
Multidrug Resistant ◽  
Chemical Components ◽  
Resistant Bacteria ◽  
Transmission Electron ◽  
Hydroclathrus Clathratus ◽  
Adaptive Nature ◽  
First Time

AbstractThe adaptive nature of algae results in producing unique chemical components that are gaining attention due to their efficiency in many fields and abundance. In this study, we screened the phytochemicals from the brown alga Hydroclathrus clathratus and tested its ability to produce silver nanoparticles (AgNPs) extracellularly for the first time. Lastly, we investigated its biological activity against a variety of bacteria. The biosynthesized nanoparticles were characterized by UV-visible spectroscopy, Fourier-transform infrared spectroscopy, dynamic light scattering, transmission electron microscopy, and energy-dispersive spectroscopy. The biological efficacy of AgNPs was tested against eighteen different bacteria, including seven multidrug-resistant bacteria. Phytochemical screening of the alga revealed the presence of saturated and unsaturated fatty acids, sugars, carboxylic acid derivatives, triterpenoids, steroids, and other components. Formed AgNPs were stable and ranged in size between 7 and 83 nm and presented a variety of shapes. Acinetobacter baumannii, Staphylococcus aureus, Methicillin-resistant S. aureus (MRSA), and MDR A. baumannii were the most affected among the bacteria. The biofilm formation and development assay presented a noteworthy activity against MRSA, with an inhibition percentage of 99%. Acknowledging the future of nano-antibiotics encourages scientists to explore and enhance their potency, notably if they were obtained using green, rapid, and efficient methods.

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.

scholarly journals The Radiosensitizing Effect of Zinc Oxide Nanoparticles in Sub-Cytotoxic Dosing Is Associated with Oxidative Stress In Vitro

Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4062
Author(s):  
Till Jasper Meyer ◽  
Agmal Scherzad ◽  
Helena Moratin ◽  
Thomas Eckert Gehrke ◽  
Julian Killisperger ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Dna Damage ◽  
Zinc Oxide ◽  
Zinc Oxide Nanoparticles ◽  
Oxidative Dna Damage ◽  
Clonogenic Survival ◽  
Oxide Nanoparticles ◽  
Radiosensitizing Effect ◽  
Primary Fibroblasts

Radioresistance is an important cause of head and neck cancer therapy failure. Zinc oxide nanoparticles (ZnO-NP) mediate tumor-selective toxic effects. The aim of this study was to evaluate the potential for radiosensitization of ZnO-NP. The dose-dependent cytotoxicity of ZnO-NP20 nm and ZnO-NP100 nm was investigated in FaDu and primary fibroblasts (FB) by an MTT assay. The clonogenic survival assay was used to evaluate the effects of ZnO-NP alone and in combination with irradiation on FB and FaDu. A formamidopyrimidine-DNA glycosylase (FPG)-modified single-cell microgel electrophoresis (comet) assay was applied to detect oxidative DNA damage in FB as a function of ZnO-NP and irradiation exposure. A significantly increased cytotoxicity after FaDu exposure to ZnO-NP20 nm or ZnO-NP100 nm was observed in a concentration of 10 µg/mL or 1 µg/mL respectively in 30 µg/mL of ZnO-NP20 nm or 20 µg/mL of ZnO-NP100 nm in FB. The addition of 1, 5, or 10 µg/mL ZnO-NP20 nm or ZnO-NP100 nm significantly reduced the clonogenic survival of FaDu after irradiation. The sub-cytotoxic dosage of ZnO-NP100 nm increased the oxidative DNA damage compared to the irradiated control. This effect was not significant for ZnO-NP20 nm. ZnO-NP showed radiosensitizing properties in the sub-cytotoxic dosage. At least for the ZnO-NP100 nm, an increased level of oxidative stress is a possible mechanism of the radiosensitizing effect.

scholarly journals Immunohistochemical Study of Nrf2-Antioxidant Response Element as Indicator of Oxidative Stress Induced by Cadmium in Developing Rats

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Sergio Montes ◽  
Daniel Juárez-Rebollar ◽  
Concepción Nava-Ruíz ◽  
Aurora Sánchez-García ◽  
Yesica Heras-Romero ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Morphological Changes ◽  
Antioxidant Response ◽  
Protective Mechanism ◽  
Antioxidant Response Element ◽  
Response Element ◽  
Expression Of Genes ◽  
Old Rats ◽  
Kidney Liver

In developing animals, Cadmium (Cd) induces toxicity to many organs including brain. Reactive oxygen species (ROS) are often implicated in Cd-inducedtoxicity and it has been clearly demonstrated that oxidative stress interferes with the expression of genes as well as transcriptional factors such as Nrf2-dependent Antioxidant Response Element (Nrf2-ARE). Cd-generated oxidative stress and elevated Nrf2 activity have been reportedin vitroandin situcells. In this study we evaluated the morphological changes and the expression pattern of Nrf2 and correlated them with the Cd concentrations in different ages of developing rats in heart, lung, kidney, liver, and brain. The Cd content in different organs of rats treated with the metal was increased in all ages assayed. Comparatively, lower Cd brain levels were found in rats intoxicated at the age of 12 days, then pups treated at 5, 10, or 15 days old, at the same metal dose. No evident changes, as a consequence of cadmium exposure, were evident in the morphological analysis in any of the ages assayed. However, Nrf2-ARE immunoreactivity was observed in 15-day-old rats exposed to Cd. Our results support that fully developed blood-brain barrier is an important protector against Cd entrance to brain and that Nrf2 increased expression is a part of protective mechanism against cadmium-induced toxicity.

scholarly journals The production of mature oocytes from adult ovaries following primary follicle culture in a marsupial

Reproduction ◽  
2009 ◽  
Vol 138 (2) ◽  
pp. 247-255 ◽  
Author(s):  
A Nation ◽  
L Selwood
Keyword(s):  
Normal Growth ◽  
Primary Follicle ◽  
Follicle Culture ◽  
Nuclear Maturation ◽  
Transmission Electron ◽  
Progressive Growth ◽  
Sminthopsis Macroura ◽  
First Time

A model marsupial culture system has been developed whereby individual primary follicles, obtained from adult ovaries, can be grown in vitro to the antral stage and oocytes retrieved from these follicles can achieve nuclear maturation (metaphase II) in the presence of LH. Primary follicles isolated from adult Sminthopsis macroura ovaries were cultured individually in one of four systems: microdrops under oil, upright, inverted, or roller culture. After 6 days of culture, cumulus–oocyte complexes (COCs) were excised from early antral follicles and incubated for an additional 24 h to assess meiotic competence and the effects of LH and lithium on oocyte maturation. Histology and transmission electron microscopy established normal in vivo standards and verified oocyte and follicular integrity following culture. On day 6 of culture, follicle viability was significantly greater in the inverted system (73%) than in the other three systems (10–46%). The inverted system was the most effective in supporting development with follicles demonstrating progressive growth during culture and showing antral signs by day 4. Meiotic resumption during COC culture was facilitated by LH, but hindered by lithium. The ability to resume meiosis and progress to metaphase II was equivalent in oocytes retrieved following follicle culture and those matured in vivo. This study highlights the importance of oxygen and nutrient availability during marsupial follicle culture, and demonstrates for the first time that primary follicles isolated from adult mammalian ovaries can undergo normal growth and development in vitro, to produce mature, meiotically competent oocytes.

scholarly journals The protective effect of klotho against contrast-associated acute kidney injury via the antioxidative effect

2019 ◽  
Vol 317 (4) ◽  
pp. F881-F889 ◽  
Author(s):  
Hyung Jung Oh ◽  
Hyewon Oh ◽  
Bo Young Nam ◽  
Je Sung You ◽  
Dong-Ryeol Ryu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Kidney Injury ◽  
Antioxidative Effect ◽  
In Vivo Experiments ◽  
Apoptotic Markers ◽  
Cytoplasmic Vacuoles ◽  
Transmission Electron ◽  
And Oxidative Stress

As oxidative stress is one major factor behind contrast-associated acute kidney injury (CA-AKI), we investigated the protective effect of klotho against CA-AKI via the antioxidative effect. In in vitro experiments, cells (NRK-52E) were divided into the following three groups: control, iopamidol, or iopamidol + recombinant klotho (rKL) groups. Moreover, cell viability was measured with the Cell Counting Kit-8 assay, and oxidative stress was examined with 2',7'-dichlorodihydrofluorescein diacetate fluorescence intensity. RT-PCR and Western blot analysis were performed to assess propidium iodide klotho expression, and Bax-to-Bcl-2 and apoptosis ratios were evaluated with annexin V/Hoechst 33342 staining. Furthermore, we knocked down the klotho gene using siRNA to verify the endogenous effect of klotho. In our in vivo experiments, oxidative stress was evaluated with the thiobarbituric acid-reactive substance assay, and apoptosis was evaluated with the Bax-to-Bcl-2 ratio and cleaved caspase-3 immunohistochemistry. Additionally, cell and tissue morphology were investigated with transmission electron microscopy. In both in vitro and in vivo experiments, mRNA and protein expression of klotho significantly decreased in CA-AKI mice compared with control mice, whereas oxidative stress and apoptosis markers were significantly increased in CA-AKI mice. However, rKL supplementation mitigated the elevated apoptotic markers and oxidative stress in the CA-AKI mouse model and improved cell viability. In contrast, oxidative stress and apoptotic markers were more aggravated when the klotho gene was knocked down. Moreover, we found more cytoplasmic vacuoles in the CA-AKI mouse model using transmission electron microscopy but fewer cytoplasmic vacuoles in rKL-supplemented cells. The present study shows that klotho in proximal tubular cells can protect against CA-AKI via an antioxidative effect.

scholarly journals Differentiation of a teratocarcinoma line: preferential development of cholinergic neurons.

1981 ◽  
Vol 88 (1) ◽  
pp. 57-66 ◽  
Author(s):  
S E Pfeiffer ◽  
H Jakob ◽  
K Mikoshiba ◽  
P Dubois ◽  
J L Guenet ◽  
...  
Keyword(s):  
Morphological Changes ◽  
Cholinergic Neurons ◽  
Carcinoma Cells ◽  
Sodium Influx ◽  
Average Cell ◽  
Transmission Electron ◽  
Neuronal Processes ◽  
Embryonic Antigen ◽  
Average Cell Volume

A line of embryonal carcinoma cells, PCC7-S, established in vitro from a spontaneous testicular teratocarcinoma, has been studied. Upon removing the cells from a low density monolayer culture system and permitting the cells to form aggregates in suspension, we observed a change of several physical and biochemical parameters: (a) reduction in average cell volume, (b) blockage and accumulation of cells in G1, (c) rise in secreted protease activity, (d) rise in acetylcholinesterase and choline acetyltransferase activities, and (e) disappearance of embryonic antigen F9. Although PCC7 aggregates did not undergo substantial morphological changes while suspended, when aggregates 4 or more days old were allowed to attach to plastic tissue culture dishes, substantial neurite outgrowth occurred over the next 1-3 d. This process was markedly enhanced by the addition to the growth medium of carboxymethylcellulose and inhibitors of DNA synthesis. Transmission electron microscopy disclosed a neurite ultrastructure consistent with that of neuronal processes. A veratridine-stimulated, tetrodotoxin-blocked sodium influx of 100 nmol/min per mg protein was also observed in these differentiated surface cultures. This cell line is discussed in terms of its utility for the study of early events leading to a commitment to cellular differentiation, as well as for the investigation of terminal differentiation to cholinergic neurons.

Ultrastructural Characterization of Platelet-Activating Factor-Stimulated Human Eosinophils from Patients with Asthma

1993 ◽  
Vol 84 (4) ◽  
pp. 391-399 ◽  
Author(s):  
Claus Kroegel ◽  
Ann Dewar ◽  
Tatsuo Yukawa ◽  
Per Venge ◽  
Peter J. Barnes ◽  
...  
Keyword(s):  
Morphometric Analysis ◽  
Morphological Changes ◽  
Shape Change ◽  
Platelet Activating Factor ◽  
Eosinophil Cationic Protein ◽  
Cell Periphery ◽  
Cationic Protein ◽  
Asthmatic Patients ◽  
Transmission Electron

1. Purified human eosinophils from asthmatic patients were stimulated with platelet-activating factor in vitro and examined for morphological changes by transmission electron and light microscopy. Changes were also evaluated by morphometric analysis and were related to the platelet-activating factor-stimulated release of granular eosinophil cationic protein. 2. Stimulation of eosinophils with platelet-activating factor induced a dose-dependent shape change, including the elongation of cells, loss of microvilli and the formation of lamellipodia. This effect was maximal at 25 min and was reversible. 3. Stimulation with platelet-activating factor also induced granule movement to the cell periphery and fusion of adjacent granules. Granules became swollen and vesiculated, whereas both the matrix and core showed evidence of solubilization. 4. There was a time-dependent secretion of eosinophilic cationic protein from human eosinophils upon stimulation with platelet-activating factor which occurred without significant lactate dehydrogenase release. 5. Morphometric analysis of the transmission electron micrographs indicated a significant reduction in cytoplasmic area after 10 min of incubation with platelet-activating factor from 39.0 ± 1.7 μm2 for untreated eosinophils to 33.2 ± 2.3 μm2 (P < 0.02) for platelet-activating factor-treated cells, underscoring the observation that the cells change from spherical to ellipsoidal. No significant increase in the perimeter of the cells was found. 6. The number of granule-profiles in platelet-activating factor-stimulated eosinophils was slightly reduced when compared with control, and an increase in granule area was observed 10 min after platelet-activating factor challenge (0.215 ± 0.011 μm2 versus 0.246 ± 0.016 μm2). 7. Human eosinophils from patients with asthma stimulated with platelet-activating factor undergo both cellular and granular alterations and reorganization which parallel the release of granular eosinophil basic protein.

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