COMBINED EFFECTS OF X-IRRADIATION AND 3′-METHYL-4-DIMETHYLAMINOAZOBENZENE ON LIVER CELL POPULATION

Livers of rats were exposed to 950 rads of X-irradiation. The liver cells were then induced to proliferate by the stimulus of partial hepatectomy. The regenerating livers consisted of two cell populations, one of colonies of ceils having normal amounts of DNA and the other having abnormal polyploid and aneuploid cells. Regeneration of the liver is attributed to the colonies with normal cells. When 3′-Me-DAB was fed to the X-irradiated animals, the behavior of these cell populations was reversed. The multiplication of abnormal cells was favored in the presence of the carcinogen. Changes in the percentage of mitotic irregularities, the mitotic rates, and the proportion of various stages of mitosis that resulted in the altered behavior of cell populations are discussed.

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FORMATION OF CELL COLONIES IN X-IRRADIATED REGENERATING LIVERS OF RATS

Canadian Journal of Biochemistry ◽

10.1139/o65-092 ◽

1965 ◽

Vol 43 (6) ◽

pp. 817-828 ◽

Cited By ~ 9

Author(s):

M. Maini Webber ◽

H. F. Stich

Keyword(s):

Partial Hepatectomy ◽

Cell Population ◽

Selection Pressure ◽

Precancerous Lesion ◽

Abnormal Chromosome ◽

Cell Populations ◽

Chemical Carcinogen ◽

Normal Cells ◽

Heterogeneous Cell Population ◽

High Incidence

A high incidence of mitotic irregularities was observed when X-irradiated livers were induced to regenerate after a partial hepatectomy. Mitotic irregularities resulted in the formation of a heterogeneous cell population. As regeneration proceeded, the liver was found to be composed of two different cell populations: (i) one consisting of polyploid and aneuploid cells and incapable of giving rise to many descendants, and (ii) another consisting of apparently normal cells and capable of extensive proliferation which resulted in the formation of cell colonies. The regeneration of liver is mainly attributed to the cell colonies. No tumors appeared in the liver. These results demonstrate that a heterogeneous cell population of a "precancerous lesion" does not necessarily lead to the formation of a neoplasm. A selection pressure can be considered as necessary to favor the multiplication of cells with abnormal chromosome complements over that of cells with normal complements, as is seen in the livers of rats fed a chemical carcinogen. However, in the case of X-irradiated livers, normal cells seem to be favored.

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Mitochondria Load Degree in Hepatocytes of the Classical Hepatic Lobules in Chinchilla (Chinchilla lanigera)

Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca Veterinary Medicine ◽

10.15835/buasvmcn-m:2021.0004 ◽

2021 ◽

Vol 78 (1) ◽

pp. 76

Author(s):

Ioan Florin GHIURCO ◽

Aurel DAMIAN ◽

Vasile Florin RUS ◽

Cristian MARTONOS ◽

Maria Cătălina MATEI ◽

...

Keyword(s):

Cell Population ◽

Liver Cell ◽

Morphological Features ◽

Uneven Distribution ◽

Hepatic Lobule ◽

Intimate Contact ◽

Functional Complexity ◽

Liver Fragments ◽

Pathology Of The Liver ◽

Liver Cell Population

Hepatocytes represent the majority of the liver cell population and are arranged in the form of cords placed in intimate contact with the sinusoidal capillaries. The functional complexity corroborated with the intensity of the activity of hepatocytes requires large amounts of energy. The organelles involved in the production of chemical energy used in the activity of hepatocytes are the mitochondria. The purpose of this study was to verify the mitochondrial load of hepatocytes in all areas of the classical hepatic lobules, in order to indirectly assess the intensity of hepatocyte activity in each area. Materials and Methods Five fresh corpses of chinchilla (Chinchilla lanigera) from an independent breeder from Bistrița-Năsăud county were used. Liver fragments were harvested and fixated in Kolster’s solution for 24 hours, stained with Heidenhain ferric hematoxylin, and assessed using Olympus BX41 microscope. Fixation with Kolster's solution and the staining with Heidenhain's iron hematoxylin clearly shows the hepatocytic mitochondria in shades from gray to black. The liver lobules displayed an uneven distribution of mitochondria depending on the area. In zone 1 of the classical hepatic lobule, the degree of loading of hepatocytes with mitochondria is larger than in zone 2 and much larger than in zone 3. Morphological features of the hepatocytes, including the number and distribution of mitochondria in the hepatic lobules, should improve the understanding of the physiology and pathology of the liver.

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Characterization of a Fetal Liver Cell Population Endowed with Long-Term Multiorgan Endothelial Reconstitution Potential

Stem Cells ◽

10.1002/stem.2494 ◽

2016 ◽

Vol 35 (2) ◽

pp. 507-521 ◽

Cited By ~ 3

Author(s):

Ana Cañete ◽

Valentine Comaills ◽

Isabel Prados ◽

Ana María Castro ◽

Seddik Hammad ◽

...

Keyword(s):

Cell Population ◽

Liver Cell ◽

Fetal Liver ◽

Fetal Liver Cell ◽

Liver Cell Population

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Faculty Opinions recommendation of Distinct proteomic features of two fibrogenic liver cell populations: hepatic stellate cells and portal myofibroblasts.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.4934958.4874056 ◽

2010 ◽

Author(s):

Jonathan A Dranoff ◽

Michel Fausther

Keyword(s):

Liver Cell ◽

Hepatic Stellate Cells ◽

Stellate Cells ◽

Cell Populations

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Discrete and continuum phenotype-structured models for the evolution of cancer cell populations under chemotherapy

Mathematical Modelling of Natural Phenomena ◽

10.1051/mmnp/2019027 ◽

2020 ◽

Vol 15 ◽

pp. 14 ◽

Cited By ~ 5

Author(s):

Rebecca E.A. Stace ◽

Thomas Stiehl ◽

Mark A.J. Chaplain ◽

Anna Marciniak-Czochra ◽

Tommaso Lorenzi

Keyword(s):

Cancer Cell ◽

Cell Population ◽

Evolutionary Dynamics ◽

Analytical Description ◽

Chemotherapeutic Agents ◽

Cell Populations ◽

Theoretical Ground ◽

Individual Based Model ◽

Nonlocal Parabolic Equation ◽

Epigenetic Drug

We present a stochastic individual-based model for the phenotypic evolution of cancer cell populations under chemotherapy. In particular, we consider the case of combination cancer therapy whereby a chemotherapeutic agent is administered as the primary treatment and an epigenetic drug is used as an adjuvant treatment. The cell population is structured by the expression level of a gene that controls cell proliferation and chemoresistance. In order to obtain an analytical description of evolutionary dynamics, we formally derive a deterministic continuum counterpart of this discrete model, which is given by a nonlocal parabolic equation for the cell population density function. Integrating computational simulations of the individual-based model with analysis of the corresponding continuum model, we perform a complete exploration of the model parameter space. We show that harsher environmental conditions and higher probabilities of spontaneous epimutation can lead to more effective chemotherapy, and we demonstrate the existence of an inverse relationship between the efficacy of the epigenetic drug and the probability of spontaneous epimutation. Taken together, the outcomes of the model provide theoretical ground for the development of anticancer protocols that use lower concentrations of chemotherapeutic agents in combination with epigenetic drugs capable of promoting the re-expression of epigenetically regulated genes.

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Liver cell hydration and integrin signaling

Biological Chemistry ◽

10.1515/hsz-2021-0193 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Michele Bonus ◽

Dieter Häussinger ◽

Holger Gohlke

Keyword(s):

Cell Volume ◽

Liver Cell ◽

Cell Function ◽

The Other ◽

Signaling Cascades ◽

Integrin Signaling ◽

Volume Changes ◽

The One ◽

And Oxidative Stress

Abstract Liver cell hydration (cell volume) is dynamic and can change within minutes under the influence of hormones, nutrients, and oxidative stress. Such volume changes were identified as a novel and important modulator of cell function. It provides an early example for the interaction between a physical parameter (cell volume) on the one hand and metabolism, transport, and gene expression on the other. Such events involve mechanotransduction (osmosensing) which triggers signaling cascades towards liver function (osmosignaling). This article reviews our own work on this topic with emphasis on the role of β1 integrins as (osmo-)mechanosensors in the liver, but also on their role in bile acid signaling.

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Inactivation of Surface-adherent Listeria monocytogenes Hypochlorite and Heat

Journal of Food Protection ◽

10.4315/0362-028x-54.1.4 ◽

1991 ◽

Vol 54 (1) ◽

pp. 4-6 ◽

Cited By ~ 86

Author(s):

SHIN-HO LEE ◽

JOSEPH F. FRANK

Keyword(s):

Stainless Steel ◽

Listeria Monocytogenes ◽

Cell Population ◽

Incubation Time ◽

Cell Populations ◽

Adherent Cell ◽

Adherent Cells ◽

D Cells

Inactivation by hypochlorite of Listeria monocytogenes cells adherent to stainless steel was determined. Adherent cell populations were prepared by incubating stainless steel slides with a 24 h culture of L. monocytogenes for 4 h at 21°C. Adherent microcolonies were prepared by growing L. monocytogenes on stainless steel slides submerged in a 1:15 dilution of tryptic soy broth at 21°C. The slides were then rinsed and transferred to fresh sterile broth every 2 d with a total incubation time of 8 d. Although the 4 h and 8 d adherent populations were at similar levels, 8 d adherent cells were over 100 times more resistant than the 4 h adherent cell population when exposed to 200 ppm hypochlorite for 30 s. When stainless steel slides containing adherent cells were heated at 72°C both adherent cell populations were inactivated after 1 min. Detectable numbers of L. monocytogenes remained on stainless steel slides after treatment at 65°C for 3 min when adherent 8 d cells were tested but not when adherent 4 h cells were used.

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