Biohybrid artificial organs encompass all devices capable of substituting for an organ or tissue function and are fabricated from both synthetic materials and living cells. The viability of engineered tissue could be related to the viability of implanted cells. The system of viability assay for mammalian cell culture can be applied to the determination of cell viability for engineered tissue. This review explores various methods of cell viability assay which can be applied to the viability evaluation of engineered tissue. The major criteria employed in viability assays include survival and growth in tissue culture, functional assay, metabolite incorporation, structural altercation, and membrane integrity. Each viability assay method is based on different definitions of cell viability, and has inherent advantages and disadvantages. In order to be able to assess the viability of cells with one assay method, it is desirable to compare the viability measurements from various assays derived from different criteria.
Animal ; Biomedical Engineering*/methods ; Cell Division ; Cell Survival ; Human

OBJECTIVETo investigate the biological characteristics of cell lines of healthy and diseased human dental alveoli.

METHODSPrimary cell lines from either healthy or diseased human dental alveoli were obtained. Two cell lines, H-258 and H-171 derived from healthy and diseased human tissues respectively, were selected for morphological study and research on their growth and aging, using cell counting, and histochemical and immunohistochemical staining.

RESULTSPrimary cell lines were successfully established from innormal dental alveoli. After freezing and thawing for three times, cell growth was continued and no morphological alterations were observed. The doubling time was 53.4 hours and mean division index (MDI) was 4 per thousand. Cells were kept normal after twenty generations with no obvious reduction of doubling time and MDI. Of twenty-six primary cell lines derived from healthy human dental alveoli, only three cell lines achieved generation. After freezing and thawing for twice, cultured cells were still alive at a decreased growth speed, with doubling time of 85.9 hours and MDI of 3 per thousand. Both cell lines, H-171 and H-258, shared the characteristics of osteoblast.

CONCLUSIONSPrimary cell lines of diseased human dental alveoli show greater growth potential. All cell lines of dental alveoli share characteristics of osteoblast. The technique we developed may be put into practice for the treatment of abnormal dental alveoli.

At the level of individual cells, signaling is crucial in cell division, differentiation, metabolic control and death. Reception of the signals depends on receptor proteins that are usually at the cell surface, and these receptor proteins bind the signal molecule. The binding activates the receptor, which in turn activates one or more of the intra-cellular signaling pathways. These relay chains of molecules, mainly intra-cellular signaling proteins, process the signal inside the receiving cell and distribute it to the appropriate intra-cellular targets. Cell signaling pathways are involved in the pathophysiology of many diseases and also in the mechanisms of action of many drugs, including local and general anesthetics. Knowledge of the basic cell signaling mechanisms is essential for understanding many of the pathophysiologic and pharmacologic mechanisms. Therefore, if we focus on applying the new cellular and molecular biologic research, these efforts could identify the mechanism of diseases and help develop new drugs in the field of anesthesiology and pain medicine.
Anesthesiology ; Anesthetics, General ; Blotting, Western ; Cell Division ; Proteins

The advance of experimental cell division and proliferation in the field of cell biomechanics is presented in this paper. The emphasis is placed on the research in the mechanics mechanism of cleavage furrow and in the measurement of constricting force about cleavage furrow.
Biomechanical Phenomena ; Cell Division ; physiology ; Cytokinesis ; physiology ; Humans

A recent study has proposed that dimethyl sulfoxide (DMSO) increases the number of HL-60 cells in high cell density conditions by inhibiting cell density-dependent apoptosis. We observed that dimethylformamide (DMF), a DMSO-related polar compound, also increased the concentration of HL-60 cells. The effective dose range of DMSO and DMF was 0.5-1% and 0.2-0.6% respectively. DMF, like DMSO, inhibited density-dependent apoptosis of HL-60 cells. The flow cytometric PKH26 cell proliferation assay showed DMSO and DMF actively increased cell division. However, the difference in the distribution of cell cycle phase was not noted between the control and the DMSO- or DMF-treated HL-60 cultures. Finally, DMSO and DMF stimulated HL-60 growth even in low density conditions. These results suggest that DMSO and OMF at appropriate concentrations increase the number of HL-60 cells by both apoptosis inhibition and cell division augmentation.
Apoptosis ; Cell Count ; Cell Cycle ; Cell Division ; Cell Proliferation ; Dimethyl Sulfoxide* ; Dimethylformamide* ; HL-60 Cells* ; Humans*

BACKGROUND: Renin is secreted from the juxtaglomerular (JG) cells in response to a wide variety of extracellular stimuli. To study the underlying mechanism of regulation of renin secretion at molecular level, pure JG cell lines (As 4.1) cloned from renal JG tumor was used. In this study, to explore the feasibility of As 4.1 cells as an in vitro model for renin secretion, the changes of renin secretion from As 4.1 in culture during cell cycle were characterized. METHODS: To address this issue, As 4.1s were synchronized in G0, G1, S, G2, early M and late M phase during experiment. RESULTS: The rate of renin secretion was above 1 ng AI/well/hr in G0, G2/M and early mitotic phase and 0.5 ng AI/well/hr in G1, G1/S, S and late mitotic phase. ML-7 (6x10(-5) M), an inhibitor of MLCK which is known to stimulate renin secretion, increased the rate of renin secretion much greater in G1, G1/S, S and late M phase than the other phases; in particular, in early mitotic phase it had no stimulation. On the other hand, the rate of renin secretion was not influenced through out cell cycles by calyculin A, an inhibitor of type 1 protein phosphatase. Forskolin, an activator of adenlyate cyclase resulting in an elevation of intracellular cyclic AMP, stimulated renin secretion only in S phase in a concentration dependent manner. CONCLUSION: The present study demonstrated that As 4.1 cells in culture secrete active renin in much the similar manner to JG cells in situ but its rate varies during each phase of the cell cycle. Thus As 4.1 cells can be utilized as an in vitro model for renin secretion. But, changes in the rate of renin secretion and the secretory responses to stimulators or inhibitors during cell cycle must be considered in conducting experiments to elucidate the cellular and molecular mechanism of the renin secretion.
Cell Cycle* ; Cell Division ; Cell Line ; Clone Cells ; Colforsin ; Cyclic AMP ; Hand ; Renin* ; S Phase

PURPOSE: Telomeres are specialized structures containing unique (TTAGGGG) repeats at the ends of eukaryotic chromosomes that are thought to be important in the protection and replication of chro mosomes. Lagging strand DNA synthesis at the end of linear chromosomes cannot be complieted (referred to as the end-replication problem), and this results in the progressive shortening of telomeric repeats with each cell division. This shortening of telomeres has been proposed as the mitotic clock, and when telomeres are sufficiently short, may contribute to replicative cellular senescence in cells. The enzyme telomerase permits the de novo synthesis of telomeric DNA into chromosomal ends. Apoptosis is physiologic cell death and prevent cancerous transformation of cell. METHODS: We measured the telome rase activity with the use of a PCR-based telomerase assay and apoptosis, in 10 superficial gastritis and 13 gastric cancer patients. RESULTS: Telomerase activity was present in 70% of the gastric cancer patient and in 92.7% of the superficial gastritis patients (P=0.171). Apoptosis was present in 0% of the gastric cancer patients, and in 80% of the superficial gastritis patients (P=0.001). CONCLUSION: Telomerase activity was detected in and cancer and inflammatory tissue. Although there is progressive cellular division due to telomerase activity, cancerous transformations are prevented by apoptosis.
Apoptosis* ; Cell Aging ; Cell Death ; Cell Division ; DNA ; Gastritis* ; Humans ; Stomach Neoplasms* ; Telomerase* ; Telomere

OBJECTIVETo evaluate the effects of non-Saccharomyces albicans metabolic products on the cell cycle distribution and proliferation of human umbilical vein endothelial cell ECV304 cells in vitro.

METHODSThe parallel dilution supernatant of Saccharomyces tropicalis, Saccharomyces krusei and Saccharomyces glabrata were prepared, and 1, 4, 16-fold(s) diluted concentration and control group were set up. The line of human umbilical vein endothelial cell ECV304 was cultured in vitro and treated by non-Saccharomyces albicans supernatant. The proliferous effect of ECV304 induced by non-Saccharomyces albicans supernatant after 24, 48, 72 h was detected by the methods of MTT, and the changes of cell density and cycle after 48 h were investigated by inverted microscope and flow cytometry.

RESULTSAt the 24th hour, all of the higher concentration (1-fold) of non-Saccharomyces albicans supernatant and the 4-folds diluted Saccharomyces krusei could promote ECV304 proliferation(P < 0.05). After adding various non-Saccharomyces albicans supernatant at 48h and 72th hour, Saccharomyces krusei supernatant and Saccharomyces glabrata supernatant significantly increased proliferation rate of ECV304, while Saccharomyces tropicalis supernatant group showed no significant change no matter which concentration was tested. At 48th hour after adding the non-Saccharomyces albicans supernatant, the ECV304 cells density treated by Saccharomyces krusei supernatant and Saccharomyces glabrata supernatant were significantly higher under the inverted microscope. The G0/G1 population of ECV304 cells decreased while cell proliferation index (PI) increased after incubated with Saccharomyces krusei supernatant and Saccharomyces glabrata supernatant for 48 hours (P < 0.05). Saccharomyces tropicalis group showed no significant change (P > 0.05).

CONCLUSIONThe metabolic products of Sacharoymces krusei and Saccharomyces glabrata could induce proliferation of ECV304 cell, which suggests non-Saccharomyces albicans should be undergone more attention clinically in detection and treatment.

OBJECTIVETo study the effects of Saccharomyces albicans (S. albicans) on the cell cycle distribution and proliferation of human umbilical vein endothelial cell ECV304 cells in vitro.

METHODSThe line of ECV304 cultured in vitro were divided into four groups which were treated by S. albicans supernatant, S. albicans inactivated bacilli, supernatant and inactivated bacilli mixture, normal culture medium. The proliferous effect of ECV304 induced by supernatant, inactivated bacilli, supernatant and inactivated bacilli mixture using the methods of MTT, cell count, microscope and flow cytometry were conducted.

RESULTSIn the condition of different times and different culture concentrations, ECV304 cells incubated with 4-fold diluted S. albicans supernatant for 48 h increased the proliferation rate. The S and G2/M population of ECV304 cells increased after incubated with S. albicans supernatant for 40 h, which showed significant increasing cell proliferation index (PI) (P < 0.05). The PI of the cells treated by inactivated bacilli showed no significant change (P > 0.05).

CONCLUSIONS. albicans could induce ECV304 cell proliferation which depends on the release of metabolic products of S. albicans.

OBJECTIVETo approach the effects on induction of differentiation of Tca8113 cells affected by abscisic acid.

METHODSThe changes of surface differentiation markers, cell configuration, restrain of cell growth and the expression of Caspase-3 mRNA were examined by using inverted-phase contrast microscope, immunohistochemistry (IHC) and in situ hybridization in vitro. The dependablity between the surface differentiation markers and Caspase-3 mRNA was analysed.

RESULTSThe restraint of cell growth in ABA groups was higher than that of the control group (P<0.05). There was a trend that the tumor cell had transformed the normal cell. Furthermore, the time-dosage dependent relationship existed in the inhibition rate of tumor cells. The results showed that the expressions of Involucrin protein, retinoic acid receptor beta (RARbeta) and Caspase-3 mRNA in experimental group had been higher than that of control group. There was a significance between the different concentration experimental groups at 24 h (P<0.05). Moreover, the positive correlation existed among the Involucrin, RARbeta and Caspase-3 mRNA at the time of 12 hour and 24 hour (P<0.05).

CONCLUSIONThe possible mechanism is that abscisic acid acted on the tumor cell and raised the level of RARbeta gene through combining the correlative receptors so that increased the expression of Involucrin protein and promoted the activity of Caspase-3 and resulted in apoptosis of tumor cell.