Microcalorimetric measurement of aerobic cell metabolism in unstirred cell cultures

1990 ◽  
Vol 172 ◽  
pp. 105-113 ◽  
Author(s):  
A.J. Fontana ◽  
L.D. Hansen ◽  
R.W. Breidenbach ◽  
R.S. Criddle
Cells ◽  
2019 ◽  
Vol 8 (12) ◽  
pp. 1510 ◽  
Author(s):  
Anna Ligasová ◽  
Markéta Vydržalová ◽  
Renata Buriánová ◽  
Lenka Brůčková ◽  
Renata Večeřová ◽  
...  

Contamination of cell cultures by mycoplasmas is a very common phenomenon. As they can substantially alter cell metabolism and potentially spread to all cell cultures in laboratory, their early detection is necessary. One of the fastest and cheapest methods of mycoplasma detection relies on the direct staining of mycoplasmas’ DNA by DAPI or Hoechst dyes. Although this method is easy and fast to perform, it suffers from the low signal provided by these dyes compared to the nuclear DNA. Therefore, the reporter cell lines are used for cultivation of mycoplasmas before DAPI or the Hoechst staining step. In the study presented, we have developed and tested a new immunofluorescence assay for the detection of mycoplasmas. The method is based on the enzymatic labeling using DNA polymerase I and modified nucleotides utilizing nicks in the mycoplasmas’ DNA. Modified nucleotides are incorporated into mycoplasmas’ DNA and subsequently visualized by immunofluorescence microscopy. The developed approach is independent of the mycoplasma strain, does not intensely stain nuclear DNA, does not stain other bacteria, and provides higher sensitivity than the approach based on the direct labeling using DAPI or Hoechst dyes.


2020 ◽  
Vol 9 (2) ◽  
pp. 33-44
Author(s):  
K. D. Skorinova ◽  
V. V. Kuzmenko ◽  
I. A. Vasilenko

Introduction. The prospects of using nanoparticles in the production of medicines are widely discussed in the literature. In 2018 alone, the quantity of registration certificates issued by national regulators for medicines that use nanoparticles in one form or another is around forty. Most of them are medicines based on liposomes, polymers, iron oxides, micelles. So far, no registration certificates have been issued for selenium nanoparticles. One of the reasons for this situation in this area, from our point of view, is that the mechanisms of interaction of nanoparticles with cells are not sufficiently studied. The lack of basic research in this area is one of the main obstacles to the development of new-generation drugs based on nanoparticles.Text. This review is devoted to the analysis of scientific data on the interaction of selenium nanoparticles with different types of cells. The article discusses the biological properties of selenium and its role in cell metabolism. Data on the cytotoxic effect of selenium nanoparticles on various cell cultures are presented. Methods of preparation of nanoparticles and methods for studying the interaction of nanoparticles with cell cultures are described.Conclusion. Analysis of the literature data allows us to draw conclusions about the relevance of research on the interaction of selenium nanoparticles with living cells. This is necessary to determine the mechanisms of selenium nanoparticles absorption, study their cytotoxic and / or cytostatic action, and distribution in cells. Investigation of the biological interaction of selenium nanoparticles with tumor and normal cells will determine the most informative methods for registering and quantifying their antitumor activity, which is relevant for the development of new drugs to treat cancer.


2019 ◽  
Vol 9 (1) ◽  
pp. 50 ◽  
Author(s):  
Katie Morgan ◽  
Wesam Gamal ◽  
Kay Samuel ◽  
Steven D. Morley ◽  
Peter C. Hayes ◽  
...  

There are a variety of end-point assays and techniques available to monitor hepatic cell cultures and study toxicity within in vitro models. These commonly focus on one aspect of cell metabolism and are often destructive to cells. Impedance-based cellular assays (IBCAs) assess biological functions of cell populations in real-time by measuring electrical impedance, which is the resistance to alternating current caused by the dielectric properties of proliferating of cells. While the uses of IBCA have been widely reported for a number of tissues, specific uses in the study of hepatic cell cultures have not been reported to date. IBCA monitors cellular behaviour throughout experimentation non-invasively without labelling or damage to cell cultures. The data extrapolated from IBCA can be correlated to biological events happening within the cell and therefore may inform drug toxicity studies or other applications within hepatic research. Because tight junctions comprise the blood/biliary barrier in hepatocytes, there are major consequences when these junctions are disrupted, as many pathologies centre around the bile canaliculi and flow of bile out of the liver. The application of IBCA in hepatology provides a unique opportunity to assess cellular polarity and patency of tight junctions, vital to maintaining normal hepatic function. Here, we describe how IBCAs have been applied to measuring the effect of viral infection, drug toxicity/IC50, cholangiopathies, cancer metastasis and monitoring of the gut-liver axis. We also highlight key areas of research where IBCAs could be used in future applications within the field of hepatology.


Author(s):  
Gunter F. Thomas ◽  
M. David Hoggan

In 1968, Sugimura and Yanagawa described a small 25 nm virus like particle in association with the Matsuda strain of infectious canine hepatitis virus (ICHV). Domoto and Yanagawa showed that this particle was dependent on ICHV for its replication in primary dog kidney cell cultures (PDK) and was resistant to heating at 70°C for 10 min, and concluded that it was a canine adeno-associated virus (CAAV). Later studies by Onuma and Yanagawa compared CAAV with the known human serotypes (AAV 1, 2, 3) and AAV-4, known to be associated with African Green Monkeys. Using the complement fixation (CF) test, they found that CAAV was serologically related to AAV-3 and had wide distribution in the dog population of Japan.


Author(s):  
A. E. Ritchie

The cause of bluecomb disease in turkeys is unknown. Filtration of infective intestinal contents suggests a viral origin. To date, it has not been possible to isolate the etiologic agent in various cell cultures. The purpose of this work was to characterize as many virus-like entities as were recognizable in intestines of both healthy and bluecomb-infected turkeys. By a comparison of the viral populations it was hoped that some insight might be gained into the cause of this disease. Studies of turkey hemorraghic enteritis by Gross and Moore (Avian Dis. 11: 296-307, 1967) have suggested that a bacteriophage-host cell interaction may bear some causal relationship to that disease.


Author(s):  
T. M. Crisp ◽  
F.R. Denys

The purpose of this paper is to present observations on the fine structure of rat granulosa cell cultures grown in the presence of an adenohypophyseal explant and to correlate the morphology of these cells with progestin secretion. Twenty-six day old immature female rats were given a single injection of 5 IU pregnant mares serum gonadotropin (PMS) in order to obtain ovaries with large vesicular follicles. At 66 hrs. post-PMS administration (estrus indicated by vaginal smear cytology), the ovaries were removed and placed in a petri dish containing medium 199 and 100 U penicillin/streptomycin (P/S)/ml. Under a 20X magnification dissecting microscope, some 5-8 vesicular follicles/ovary were punctured and the granulosa cells were expressed into the surrounding medium. The cells were transferred to centrifuge tubes and spun down at 1000 rpm for 5 mins.


Author(s):  
J. P. Brunschwig ◽  
R. M. McCombs ◽  
R. Mirkovic ◽  
M. Benyesh-Melnick

A new virus, established as a member of the herpesvirus group by electron microscopy, was isolated from spontaneously degenerating cell cultures derived from the kidneys and lungs of two normal tree shrews. The virus was found to replicate best in cells derived from the homologous species. The cells used were a tree shrew cell line, T-23, which was derived from a spontaneous soft tissue sarcoma. The virus did not multiply or did so poorly for a limited number of passages in human, monkey, rodent, rabbit or chick embryo cells. In the T-23 cells, the virus behaved as members of the subgroup B of herpesvirus, in that the virus remained primarily cell associated.


Author(s):  
R. I. Johnsson-Hegyeli ◽  
A. F. Hegyeli ◽  
D. K. Landstrom ◽  
W. C. Lane

Last year we reported on the use of reflected light interference microscopy (RLIM) for the direct color photography of the surfaces of living normal and malignant cell cultures without the use of replicas, fixatives, or stains. The surface topography of living cells was found to follow underlying cellular structures such as nuceloli, nuclear membranes, and cytoplasmic organelles, making possible the study of their three-dimensional relationships in time. The technique makes possible the direct examination of cells grown on opaque as well as transparent surfaces. The successful in situ electron microprobe analysis of the elemental composition and distribution within single tissue culture cells was also reported.This paper deals with the parallel and combined use of scanning electron microscopy (SEM) and the two previous techniques in a study of living and fixed cancer cells. All three studies can be carried out consecutively on the same experimental specimens without disturbing the cells or their structural relationships to each other and the surface on which they are grown. KB carcinoma cells were grown on glass coverslips in closed Leighto tubes as previously described. The cultures were photographed alive by means of RLIM, then fixed with a fixative modified from Sabatini, et al (1963).


Sign in / Sign up

Export Citation Format

Share Document