scholarly journals About 4-day Rhythm of Proliferative Activity of Fibroblast-like Cell Cultures Depends on the Environmental Factor

2021 ◽  
Author(s):  
Marina A. Diatroptova ◽  
Anna M. Kosyreva ◽  
Mikhail E. Diatroptov
Keyword(s):  
Cell Cultures ◽  
Proliferative Activity ◽  
Simultaneous Increase ◽  
Embryonic Cells ◽  
Logarithmic Growth Phase ◽  
Infradian Rhythm ◽  
Cell Proliferative Activity ◽  
Embryonic Fibroblast ◽  
Logarithmic Growth

Abstract A study of the 4-day rhythm of the proliferative activity of the embryonic fibroblast-like cells in the logarithmic growth phase was carried out. It was shown that in cell cultures obtained on different days from embryos of different ages, the phase of the 4-day rhythm coincides. In vitro the maxima of the proliferative activity were consistent with the minima of the motor activity of mice. Freezing the culture for 2 or 6 days does not cause a shift in the phase of the 4-day rhythm of cell proliferative activity compare with the unfreezing culture. That indicates the existence of an external synchronizer, which determines the 4-day infradian rhythm of the proliferative activity of embryonic cells. Then we daily thawed samples of single L-929 culture of mice fibroblast-like cells for 22 and 17 days and researched the dynamics of its proliferative activity. We also showed 4-day rhythm of the simultaneous increase in the number of cells for all thawed samples. Taking into account that deep freezing of a culture leads to the cessation of all life processes, the fact we obtained indicates an exogenous mechanism of the formation of about a 4-day rhythm of the proliferative activity of cell culture.

P13.23 Study of migration characteristics of human glioma cells in vitro

2021 ◽  
Vol 23 (Supplement_2) ◽  
pp. ii37-ii38
Author(s):  
G Pavlova ◽  
S Pavlova ◽  
S Drozd ◽  
E Savchenko ◽  
L Zakharova ◽  
...  
Keyword(s):  
Cell Cultures ◽  
Proliferative Activity ◽  
Average Rate ◽  
Glioma Cells ◽  
Human Glioma ◽  
Human Gliomas ◽  
Migration Activity ◽  
Tumor Invasiveness ◽  
Grade Iii

Abstract BACKGROUND Gliomas are still one of the most aggressive human cancers, and even despite modern therapeutic approaches, the prognosis for patients with this disease is not favorable. It is known that glioma cells are capable of local invasiveness, when glioma cells migrate into healthy brain tissue. A lack of any definite markers, characterizing migrating glioma cells and allowing them to be distinguished from healthy brain cells, requires a thorough investigation. In case it would be possible to characterize invasive glioma cells, then a development of targeted therapy could be feasible. MATERIAL AND METHODS Cell cultures of human gliomas Gr II, III and IV were developed with 5 cultures for each Grade. MTT, RT-PCR, Western and Nosern blot, transcriptome analysis were applied. RESULTS Three cultures of human gliomas had a high degree of migration, within the range of 6% - 14%. These cultures were developed from gliomas of Grade III and Grade IV, and with IDH1- (minus) phenotype. Moreover, cell cultures with IDH1 + (plus) phenotype had a low migration rate within 1%. An intensity of migration correlated with the degree of malignancy, and an average rate decreased with a decrease of the Grade. Moreover, an analysis of the proliferative activity of cell cultures of human gliomas of various degrees of malignancy did not reveal a relationship with a migratory properties of cultures. A number of actively proliferating cultures did not show high migration, while cultures with medium proliferative activity could show a high level of migration. The low level of proliferation of cultures of gliomas of Grade II and I at the beginning of cultivation, in some cases, subsequently increased, but an inherent low migration activity did not change. In actively migrating cultures, a significant decrease in the expression of Sox2 and Nestin is detected. A positive correlation was found between migration abilities of human glioma cell culture cells and the marker Ki67, GFAP, Sox2, and Oct4. The difference was statistically significant by the one-sided Mann-Whitney test. CONCLUSION Conclusions: Cell cultures derived from glioma tumor tissue can be used to predict invasive properties of the tumor. High tumor invasiveness is characteristic for Grade III and Grade IV, and with IDH1- (minus) phenotype, and it also correlates with elevated expression of GFAP, Sox2 and Oct4The reported study was funded by RFBR according to the research project № 18-29-01012 and by the Ministry of Science and Higher Education of the Russian Federation, grant number 075-15-2020-809 (13.1902.21.0030).

GROWTH OF PENICILLIN-RESISTANT AND PENICILLIN-SENSITIVE STRAINS OF STAPHYLOCOCCUS AUREUS

1963 ◽  
Vol 9 (2) ◽  
pp. 179-186
Author(s):  
Wendall E. Allen ◽  
Ilda McVeigh
Keyword(s):  
Staphylococcus Aureus ◽  
Stationary Phase ◽  
Growth Phase ◽  
Growth Curves ◽  
Viable Cell ◽  
Fresh Medium ◽  
Logarithmic Growth Phase ◽  
Resistant Strains ◽  
Logarithmic Growth

Ten strains of naturally penicillin-resistant Staphylococcus aureus (obtained from patients), two in vitro derived resistant strains, and two sensitive strains, were grown at 37 C in Antibiotic Assay broth, and viable cell determinations were made at intervals. From these data, growth curves were plotted for each of the strains. The curves for the naturally penicillin-resistant and the sensitive strains are very similar. Little, if any, lag in growth of these strains occurred on transfer from maximum stationary-phase cultures to fresh medium. They grew at approximately the same rate during the logarithmic growth phase, which lasted for 3 to 4 hours; during the maximum stationary phase, about the same number of cells was present per milliliter in cultures of each of these strains. In contrast, the in vitro derived resistant strains underwent a lag of 2 to 6 hours on transfer to fresh medium and grew at a slower rate during the logarithmic growth phase. However, during the maximum stationary phase, which occurred after an incubation period of 24 to 32 hours, the cell titers were approximately the same as those of the naturally resistant and the sensitive strains. When grown in competition with either of the sensitive strains in Antibiotic Assay broth in the absence of penicillin, one of the naturally resistant strains persisted for 14 successive subcultures without any apparent change in ability to tolerate the antibiotic.

scholarly journals Modified PEHPS Medium as an Alternative for theIn VitroCulture ofGiardia lamblia

2014 ◽  
Vol 2014 ◽  
pp. 1-4 ◽  
Author(s):  
Javier Vargas-Villarreal ◽  
Benito D. Mata-Cárdenas ◽  
Magda E. Hernández-García ◽  
Jesús N. Garza-González ◽  
Laura H. De La Garza-Salinas ◽  
...  
Keyword(s):  
Trichomonas Vaginalis ◽  
Culture Medium ◽  
Culture Media ◽  
Logarithmic Growth Phase ◽  
Economic Culture ◽  
The Mean ◽  
Logarithmic Growth ◽  
Axenic Cultivation ◽  
Duplication Time

Commercial culture media present interlot variations in biological activity. We have previously designed a homemade and economic culture medium, PEHPS medium, for the axenic cultivation ofEntamoeba histolyticaandTrichomonas vaginalis. Trophozoites of amoebae and trichomonads grow well in this medium. Furthermore, the medium is stable for several months when stored frozen or refrigerated. The objective of this work was to modify PEHPS medium to support thein vitrogrowth ofGiardia lamblia. Inocula of 5 × 103trophozoites/mL ofG. lambliawere incubated at 36.5°C in modified PEHPS or TYI-S-33 medium. Then, the growths of the threeGiardiastrains in both media were compared. The logarithmic growth phase lasted 72 h; the mean yield of the strains ranged from 10.06 to 11.43 × 105Giardiatrophozoites/mL, and the range of duplication time in the three strains was from 5.67 to 6.06 in modified PEHPS medium. These growth characteristics were not significantly different from those obtained with TYI-S-33 medium. We conclude that modified PEHPS medium might be used for the axenic cultivation ofG. lamblia.

scholarly journals Fibonacci Sequence-related Phenomenon During Chondrocyte Proliferation of the Gottingen Pig Knee Tibial Plateau

2021 ◽  
Author(s):  
xiao jian wang ◽  
Wei Tian ◽  
Jian-bo Wu ◽  
Jian Zhang
Keyword(s):  
Tibial Plateau ◽  
Fibonacci Sequence ◽  
Related Phenomenon ◽  
Chondrocyte Proliferation ◽  
Logarithmic Growth Phase ◽  
Quantitative Changes ◽  
Full Separation ◽  
Logarithmic Growth ◽  
Time Point

Abstract Background The aim of our study was to observe the quantitative changes in tibial plateau chondrocytes in the proliferation process from normal Gottingen pigs in vitro and compare them with the Fibonacci sequence.Methods Chondrocytes from normal Gottingen pig tibial plateau cartilage were isolated and cultured to the third generation, and the number of chondrocytes was measured to determine whether the chondrocyte growth was at the logarithmic growth phase. Chondrocytes were added to cell culture bottles at very a low density to allow full separation and allow each chondrocyte to grow as independently as possible. Thirty single chondrocytes were selected, and the number of chondrocyte colonies were observed and recorded every day. Results Among the 30 chondrocyte colonies, the changes in the numbers of 16 chondrocyte colonies were 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, and 987, which conformed to the numbers of the Fibonacci sequence.The number of other chondrocyte colonies was lower than corresponding numbers of the Fibonacci sequence at the same time point.Conclusion The numbers of normal Gottingen pig tibial plateau chondrocytes during the proliferation process were in line with the numbers of the Fibonacci sequence.Alignment to the Fibonacci sequence may be the fastest way for changes in the numbers of normal chondrocytes during the proliferation process in vitro.

scholarly journals Investigation of Cytotoxic Effects of Recombinant Human Interferon Lambda-1 and Its Pegylated Form on Human Conjunctival Epithelial Cells

2021 ◽  
Vol 9 (4) ◽  
pp. 200-208
Author(s):  
N. A. Kikhtenko ◽  
N. A. Bondarenko ◽  
N. P. Bgatova ◽  
L. A. Oleynik ◽  
O. V. Poveshchenko ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Proliferative Activity ◽  
Cytotoxic Effect ◽  
Ultrastructural Changes ◽  
Human Interferon ◽  
Interferon Lambda ◽  
Study Results ◽  
Cell Proliferative Activity ◽  
Pegylated Form

Currently, there are no efficacious, all-purpose antiviral medicines for the treatment of ocular surface infections caused by viruses. At the same time, type III interferons demonstrate high potency for histological barriers, such as the conjunctiva. Modification of protein molecules in native products can significantly improve their pharmacodynamic properties. Thus, it seems reasonable to develop antiviral medicines based on interferon lambda (IFN-λ1) and its pegylated form (PEG IFN-λ1).The aim of the study was to evaluate the in vitro cytotoxic effect of recombinant human IFN-λ1 and its pegylated form on Chang conjunctiva clone 1-5c-4 human conjunctival cells.Materials and methods: PEG IFN-λ1 was obtained by the electron beam immobilisation method. A normal human conjunctival cell line Chang conjunctiva clone 1-5c-4 was used for cell cultivation. The MTT test was used to assess the cytotoxic effect. Cell proliferative activity was studied by measuring microelectrode impedance. Ultrastructural changes were assessed by electron microscopy. Statistical processing was performed using the Statistica 10.0 software package.Results: IFN-λ1 (37 μg/mL) and PEG IFN-λ1 (42 μg/mL) had no significant cytotoxic effect on the human conjunctiva cell culture and the cell proliferative activity. The analysis of ultrastructural changes demonstrated that IFN-λ1 activated metabolic processes in the cells, and PEG IFN-λ1 promoted differentiation and keratinisation of epithelial cells and led to modification of the cell membrane. A ten-fold increase in IFN-λ1 and PEG IFN-λ1 concentration (to 370 μg/mL and 420 μg/mL, respectively) reduced the cell viability by 15–20% as compared to the intact control.Conclusions: the study results demonstrated that IFN-λ1 and PEG IFN-λ1 could be used as active pharmaceutical ingredients in the development of medicines for the treatment of conjunctival viral infections.

A Micrurgical Method for Preparation of Chromosomes for Electron Microscopy

1967 ◽  
Vol 25 ◽  
pp. 128-129
Author(s):  
Godfrey C. Hoskins
Keyword(s):  
Electron Microscopy ◽  
Mammalian Cells ◽  
Microscope Slide ◽  
Mitotic Apparatus ◽  
Logarithmic Growth Phase ◽  
Clear Area ◽  
Fluid Environment ◽  
A Cell ◽  
Logarithmic Growth

Mammalian cells on coverslips in vitro are used during logarithmic growth phase to obtain many cells in mitosis without the use of mitotic inhibitors.Two short lengths of glass tubing attached by beeswax to a standard microscope slide provide support for the coverslip. The coverslip is placed cell side down to form a chamber with open ends for admission of microneedles and for changing the fluid environment of the cells. This open ended chamber is then filled with a physiologic salt solution such as Hanks or a growth medium such as Eagles.Microneedles governed by deFonbrune micromanipulators are admitted through the open ends of the chamber. A cell in metaphase is located, picked up by microneedle, and carried to a clear area on the coverslip (Fig. 1). The second microneedle may hold the cell while the first is moved sidewise to create an incision in the cell membrane through which the mitotic apparatus may egress.

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