Showing 4 results for Haghighipour
F. Asgari, R. Mahinpour , N. Haghighipour , L. Moradi,
Volume 10, Issue 2 (Spring 2019)
Abstract
Chronic myeloid leukemia (CML) is a malignant blood disease with a particular chromosomal aberration and it is known as a common form of leukemia. Chromene family exhibit strong anti-cancer effects. Therefore, in this study, the effect of two derivatives of dihydro-pyrano [2, 3-g] chromene family is investigated on cell toxicity and apoptosis induction in K562 cancer cells and compared them with Peripheral Blood Mononuclear (PBMC) normal cells. The K562 cell line was cultured in the presence of the mentioned chromene derivatives at a concentration of 40-200µM for 24-72 hours. The effect of these compounds on growth and viability of K562 cell line and PBMC cells were studied via MTT assay and apoptosis induction was investigated by flow cytometry. The results showed that these chromene derivatives inhibit K562 cell line growth. Moreover, increasing the chromene concentration and the time of exposure to it increase the cell toxicity. Among these compounds, 4-No2pgC was known as a compound with high toxicity (IC50=129±2.75) and 4-MePgC recognized as a compound with low toxicity (IC50=214±3.42) after 72 hours exposure to the K562 cell line. Furthermore, the results of flow cytometry demonstrated the effect of apoptosis induction of these compounds on the K562 cell line. According to the obtained results from this research, chromene derivatives can induce apoptosis in the K562 cell line and these compounds have a less toxic effect on normal cells than cancer cells. In conclusion, these derivatives can be considered as a proper candidate for the treatment of leukemia.
Volume 12, Issue 4 (10-2010)
Abstract
Objective: Endothelium is a selective and permeable membrane for transferring nutrients and vital components to arterial wall. Endothelial damage might lead to altered biological function of endothelium and clinical consequences such as atherosclerosis. Blood pressure pulse always exerts circumferential tension to the arterial wall. Hence, such tension together with other loads, play important role in functional properties of endothelial cells. Previous studies verify effects of cyclic loading on adaptation and remodeling of endothelium. This study investigates structural properties of cultured endothelial cells subjected to uni-axial cyclic loading.
Materials and Methods: Human umbilical vein endothelial cells, prepared from national cell bank of Iran (NCBI-C554), were cultured on silicon membrane, and then subjected to cyclic tension with 10 % amplitude and 1 Hz frequency, and 2,4,6,8 hour durations utilizing a custom made tensile device. Viscoelastic properties of endothelial cells were examined by micropipette aspiration technique.
Results: Results show increase in elastic modulus (E) of cells due to tensile cyclic loading which results in stiffening of cell body. Also results show primary increase then subsequent decrease in viscose modulus.
Conclusion: Previous studies verify generation of stress fibers due to accumulation and increase in actin fibers in endothelial cells after tensile cyclic loading. Since mechanical and structural properties of endothelial cells depend on actin fibers, results of this study show tensile cyclic loading causes increase in stiffness of endothelial cells through generation of stress fibers.
Volume 13, Issue 4 (1-2011)
Abstract
Objective: Cell vital function has correlation with mechanical loadings that cell experiences. Here, effects of in-vitro combined cyclic-static stretch on proliferation of human mesenchymal stem cell (HMSC) were evaluated.
Materials and Methods: HMSCs were cultured on gelatin coated elastic membranes, and exposed to stretch loading. Four different regimes of cyclic, static, combined cyclic-static, and cyclic with a period of unloading were exerted on the elastic membrane. Duration of cyclic loading and static loading was 5 and 12 hours respectively.
Results: The results illustrate that 10% cyclic stretch causes cell alignment but there were no significant proliferation differences between control and test group. Combined cyclic-static stretch reduced proliferation significantly while cyclic stretch with an unloading period increased cell proliferation significantly. At last, static stretch did not affect cell proliferation significantly.
Conclusion: Cell stretching regimes and post-loading duration are effective factors on cell proliferation.
Volume 16, Issue 3 (12-2013)
Abstract
The provision of an adequate quantity of cells with proper function and purity is one of the main challenges of tissue engineering studies. Stem cells, with their self-renewal and differentiation capacity, are considered one of the main cell sources in the field of tissue engineering. Previously, the use of chemical factors seemed to be the only possible way for stem cell differentiation. However, scientists have recently realized that physiological processes of the human body are composed of chemical, mechanical and electrical signals. Mechanical stimulation is one of the current methods that produce cells with proper morphology and alignment in the scaffold. Specific differentiation, a higher rate of cell growth, proliferation and differentiation, and lower experiment costs can be achieved using mechanical stimulation. Different parameters such as the chemical environment, physical environment that surrounds the cell (including geometry, stiffness and topology of scaffold surface), amplitude, frequency, and duration of mechanical stimulation can affect the stem cell fate. In this study we have investigated the impact of all types of mechanical stimulations under different loading regimes on the fate of stem cells with respect to the target tissue. The result has been reflected in the design of a proper bioreactor.
