Investigation of Mechanism of Proliferation Promotion of Cultured Osteoblasts by Mechanical Vibration

2011 ◽  
Author(s):  
Toshihiko Shiraishi ◽  
Kazutaka Ohashi ◽  
Shin Morishita ◽  
Ryohei Takeuchi
Keyword(s):  
Cell Proliferation ◽  
Time Evolution ◽  
Phase Contrast ◽  
Mechanical Vibration ◽  
Inertia Force ◽  
Cross Sectional ◽  
Microscopic Images ◽  
Inverted Microscope ◽  
Sinusoidal Excitation ◽  
Number Of Cells

This paper describes effects of mechanical vibration on osteoblasts. Their cell proliferation was investigated when sinusoidal inertia force was applied to the cells. After the cells were cultured in culture plates in a CO2 incubator for one day and adhered on the cultured plane, vibration group of the culture plates was set on an aluminum plate attached to a exciter and cultured under sinusoidal excitation of 0.5 G and 12.5 Hz for 24 hours a day in another incubator separated from non-vibration group during 21 days of culture. The time evolution of cell density was obtained by counting the number of cells with a hemocytometer. The phase contrast microscopic images and the cross-sectional confocal microscopic images of cells were captured under an inverted microscope system. As a result, it is found that the mechanical vibration elongated the pseudopods of cells to enhance their mobility resulting in promoting multilayer of the cells.

Effects of Mechanical Vibration on Osteoblast-Like Cell Line

2005 ◽  
Author(s):  
M. Kumaoka ◽  
T. Shiraishi ◽  
S. Morishita
Keyword(s):  
Cell Proliferation ◽  
Cell Line ◽  
Cell Density ◽  
Mechanical Stimulation ◽  
Bone Matrix ◽  
Mechanical Vibration ◽  
Inertia Force ◽  
Alizarin Red ◽  
Calcium Salts ◽  
Sinusoidal Excitation

Bone formation is subject in vivo to mechanical stimulation. Though many researches for bone cells of osteoblastic lineage sensing and responding to mechanical stimulation have been reported mainly in the biochemical field, the effects of mechanical stimulation are not so understood. In this study, in order to clarify the effects of mechanical vibration on osteoblast-like cells on the basis of the dynamic properties of the cells in the sense of vibration engineering, sinusoidal excitation was applied to the cells, and their cell proliferation and bone matrix generation were investigated as their frequency response. We developed an electromagnetic exciter of culture plates of the cells, which was designed with high stiffness to excite the whole area of the plates uniformly. We seeded MC3T3-E1, which is a mouse calvaria osteoblast-like cell line, and applied sinusoidal excitation for 24 hours a day for 28 days at the frequency of 12.5 or 100 Hz, setting the acceleration amplitude of 0.5 G to fix the inertia force to the cells. As the experimental results of counting the number of the cells using a hemocytometer, the cell density of all the vibrating groups was higher than that of the non-vibrating group after 14-day cultivation. In the most effective case of the frequency of 12.5 Hz and the cultured period of 25 days, the cell density of the vibrating group was higher than that of the non-vibrating group by about 26 %. That was also morphologically shown by the microscopic observation of the cells. By staining the cells with alizarin red S solution, the amount of the generated calcium salts as one of the bone matrices was measured. The amount of the calcium salts of the vibrating groups was higher than that of the non-vibrating group on 28-day cultivation. The number and the size of the nodules of the calcium salts were different depending on the excited frequency. These results of this study suggest that the mechanical vibration promotes the cell proliferation and the bone matrix generation, and that the effects of the mechanical vibration depend on the frequency.

Investigation of Promotion of Bone Matrices in Cultured Osteoblasts by Mechanical Vibration

2009 ◽  
Author(s):  
Toshihiko Shiraishi ◽  
Tetsuo Shikata ◽  
Shin Morishita ◽  
Ryohei Takeuchi
Keyword(s):  
Gene Expression ◽  
Calcium Salt ◽  
Mechanical Vibration ◽  
Polymerase Chain Reaction Method ◽  
Inertia Force ◽  
Chain Reaction ◽  
Mass Generation ◽  
Alizarin Red ◽  
Polymerase Chain ◽  
Sinusoidal Excitation

This paper describes effects of mechanical vibration on osteoblasts. Their bone mass generation was investigated when sinusoidal inertia force was applied to the cells. After the cells were cultured in culture plates in a CO2 incubator for one day and adhered on the cultured plane, vibration group of the culture plate was set on an aluminum plate attached to a exciter and cultured under sinusoidal excitation of 0.5 G and 25 Hz for 24 hours a day in another incubator separated from non-vibration group during 28 days of culture. Gene expression of alkaline phosphatase (ALP) was measured by a real-time reverse transcription polymerase chain reaction method. ALP activity was measured by Azo-dye method. Calcium salts generated by the cells were observed by being stained with alizarin red S solution. As a result, it is found that the mechanical vibration accelerates the gene expression and protein generation of ALP, and the calcium salt generation.

Control of Apoptosis and Differentiation of Cultured Neural Stem Cells by Mechanical Vibration

2009 ◽  
Author(s):  
Toshihiko Shiraishi ◽  
Kei Suzuki ◽  
Shin Morishita ◽  
Hiroshi Kanno
Keyword(s):  
Stem Cells ◽  
Cell Proliferation ◽  
Neural Stem Cells ◽  
Mechanical Vibration ◽  
Inertia Force ◽  
Rt Pcr ◽  
Experimental Conditions ◽  
Acceleration Amplitude ◽  
Phosphorylated Akt ◽  
Pcr Method

In this study, sinusoidal inertia force was applied to cultured neural stem cells and the effects of mechanical vibration on the cells were investigated. Neural stem cells which were obtained from the hippocampus of an adult Fischer rat were seeded in culture plates at the density of 2.5 × 105 cells/ml. After cells were cultured for one day and adhered on the cultured plate, vibration groups of the culture plates were set on the aluminum plate of the experimental setup and cultured under sinusoidal excitation in another CO2 incubator separated from non-vibration groups of the culture plates. Acceleration amplitude was set to 0.25 or 0.5 G and frequency was set to 12.5, 25, or 50 Hz. Time evolution of cell density was obtained by counting the number of cells with a hemocytometer. The expression of Akt, phosphorylated Akt, MAPK, and phosphorylated MAPK was detected by western blotting analysis to understand the mechanism of cell proliferation. Gene expression of MAP-2, neurofilament-H, GFAP, and nestin was detected by a real-time RT-PCR method to obtain a ratio of differentiation of neural stem cells to nerve or glia cells. The results to be obtained are as follows. The mechanical vibration at 25 Hz is most effective on cell proliferation of the present experimental conditions at 0.25 G. The enhancement of cell proliferation is probably caused by the suppression of apoptosis. The differentiation of the neural stem cells depends on acceleration amplitude and the mechanical vibration may maintain some properties of stem cells.

scholarly journals CORRELATION OF KI67 LEVEL TO METASTATIC EVENTS IN NASOPHARYNGEAL CARCINOMA

2020 ◽  
Vol 2 (02) ◽  
pp. 31-34
Author(s):  
Eriza ◽  
Ermalinda Kurnia ◽  
Denny Satria Utama
Keyword(s):  
Cell Proliferation ◽  
Nasopharyngeal Carcinoma ◽  
Correlation Analysis ◽  
Correlation Coefficient ◽  
Distant Metastases ◽  
Abdominal Ultrasound ◽  
Neck Surgery ◽  
Cross Sectional ◽  
Ki67 Expression ◽  
Positive Correlation

Introduction Nasopharyngeal carcinoma (KNF) is a malignant squamous cell tumor occurring in the nasopharyngeal epithelial region where the cuboid epithelium is transformed into squamous cells. One of the typical signs of malignancy is uncontrolled cell proliferation. K67 is an immunohistochemical (IHC) test to assess cell proliferation activity. Increased Ki67 expression is associated with increased mitotic activity in cell proliferation. Objective To determine the correlation of ki67 expression to regional and distant metastases events of nasopharyngeal carcinoma at KNF in Dr. Mohammad Hoesin Palembang. Methods This cross-sectional study was conducted on 31 subjects of KNF patients who had been diagnosed in Oncology Division of Department of Ear Nose and Throat Head Neck Surgery, then performed immunohistochemistry inspection of KI67 in Department of Anatomical Pathology of Dr. Mohammad Hoesin Palembang. The subjects were collected consecutive sampling from October to December 2017 and performed other tests for staging such as computer tomography, chest x ray and abdominal ultrasound. Results In the Ki67 level correlation analysis of the incidence of metastasis in nasopharyngeal carcinoma, the correlation coefficient was 0.98 with very strong correlation strength and the positive correlation was not statistically significant (p=0.599). However, in Ki67 level correlation analysis of histopathology result of nasopharyngeal carcinoma was found correlation coefficient of 0.385 and positive correlation which was statistically significant (p=0.032). Conclusion Ki67 levels of metastatic occurrence in nasopharyngeal carcinoma have no statistically significant correlation. However, Ki67 level on histopathological results of nasopharyngeal carcinoma and Ki67 immunoreactivity with primary tumor has a statistically significant correlation.

scholarly journals Comparación de la citocompatibilidad in vitro entre los biomateriales, fibroína y polipropileno

2017 ◽  
Vol 26 (45) ◽  
Author(s):  
Alejandro Arboleda-Carvajal ◽  
Julián González ◽  
Manuel Hernando Franco-Arias ◽  
Liliana Valladares-Torres
Keyword(s):  
Cell Proliferation ◽  
Statistical Difference ◽  
Indirect Evidence ◽  
Live Cells ◽  
Cell Behavior ◽  
In Vitro Methods ◽  
Polypropylene Material ◽  
Metabolic Reduction ◽  
Number Of Cells

This study evaluates the cell behavior of HeLa cells in vitro on fibroin and polypropylene. In order to determine cell proliferation in culture much fibroin material such as polypropylene, as the number of cells / sample was performed by the metabolic reduction of  3-(4,5- dimetiltiazol-2-ilo)-2,5-difeniltetrazol Bromide, MTT assay, using direct and indirect evidence of cytotoxicity. For direct and indirect testing of cytotoxicity in fibroin and polypropylene material, a statistical difference was found in the average number of live cells for fibroin sample regardless of the type of test (p<0.005). By the use of in vitro methods, it is shown that fibroin material has better cell behavior in terms of viability, compared with polypropylene.

Proliferation and Adhesion of L929 Fibroblasts on Surface with Different Microtopography

2014 ◽  
Vol 1648 ◽  
Author(s):  
Yuta Kurashina ◽  
Shogo Miyata ◽  
Jun Komotori ◽  
Tadayoshi Koyama
Keyword(s):  
Cell Proliferation ◽  
Cell Adhesion ◽  
Low Frequency ◽  
Polished Surface ◽  
Stainless Steel Surface ◽  
Cell Counts ◽  
Adhesion Behavior ◽  
Cell Scaffold ◽  
Cell Adhesion And Proliferation ◽  
Number Of Cells

ABSTRACTThree types of 316L stainless steel surface with different topography were prepared by a Fine Particle Peening (FPP) treatment using titania, silica and alumina shot particles and analyzed the cell proliferation and cell-scaffold interaction. FPP-treated surface with titania and silica particles had micro asperities at low frequency. On the other hand, the alumina treated surface had micro asperities at high frequency. L929 fibroblasts were seeded on these specimens and then the number of cells was counted after 72 hours of culturing. The FPP-treated surfaces showed good cell proliferation comparing to polished surface. This indicates that micro asperities formed on the surface encourage cell adhesion. Cell adhesion behavior was evaluated by a scanning electron microscope (SEM) and a fluorescence microscope. Dense filopodia were observed when cells cultured on the FPP-treated surface. This means that FPP treatment enhances cell adhesion and proliferation. The number of cells observed on the FPP-treated surface depended on the shape of asperities formed by FPP treatment; the highest cell counts were obtained on alumina treated surface. This is because cell migration was not inhibited by the shape of alumina treated surface asperities.

435 REDUCTION OF CELL CYCLE LENGTH AND INCREASE IN S-PHASE BY GROWTH FACTORS IN PIG FETAL FIBROBLASTS

2010 ◽  
Vol 22 (1) ◽  
pp. 374
Author(s):  
S. Waghmare ◽  
B. Mir
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Growth Factors ◽  
Growth Factor ◽  
Cycle Length ◽  
S Phase ◽  
Proliferation Rate ◽  
Fetal Fibroblasts ◽  
Cell Cycle Length ◽  
Number Of Cells

Gene targeting in primary somatic cells is inefficient compared with embryonic stem cells. This is because of a slow rate of cell proliferation, fewer cells in S-phase at a given time point under normal culture conditions, and low rate of homologous recombination. Homologous recombination occurs mainly in late S-phase and increase in gene targeting efficiency has been reported in S-phase synchronized cells in bovine and rhesus macaque fetal fibroblasts. In this study we tested several growth factors: platelet-derived growth factor (PDGF), tumor necrosis factor a (TNFα), epidermal growth factor (EGF), fibroblast growth factor (FGF), transforming growth factor β1 (TGFβ1), insulin-like growth factor 1 (ILGF-1) and insulin-like growth factor II (ILGF-II) individually and in various combinations to see the effect on cell proliferation rate. Each experimental set consisted of 3 replicates. TGFβ1-, ILGF1-, ILGFII-, and FGF-treated cells grew very slowly compared with untreated cells. However, a combination of 3 growth factors: PDGF (15 ng mL-1), EGF (50 ng mL-1) and TNFa (100 pg mL-1), herein referred to as the cocktail, accelerated cell proliferation rate and reduced cell cycle length on average from 24.5 ± 0.2 to 20.4 ± 0.5 h with no significant change in number of cells in S-phase. Further, cells grown in the presence of the cocktail showed changes in morphology. The cells became spindle-shaped and occupied less surface area per cell compared with untreated cells. Importantly, cocktail-treated cells maintained a normal karyotype without any chromosomal abnormality. Thymidine has been used successfully to block various cell types in S-phase but it failed to synchronize these cells in S-phase in the concentration range of 2 to 10 mM for 24 to 48 h. However, serum starvation (0.2% fetal bovine serum) for 48 h blocked the cell proliferation rate effectively and synchronized cells in G0 phase (80-82% cells). After releasing from the block, cells were grown in the absence or presence of cocktail and cell cycle analysis was done at different time points by flow cytometry. Each time point was repeated 3 times. We observed the maximum number of cells in S-phase at 22 to 23 h (61.33% ± 7.77 in cocktail-treated cells v. 41.7% ± 3.28 in untreated cells). In summary, the cocktail-treated cells showed changes in cell morphology, higher proliferation rate, reduction in cell cycle length by 16.7%, and maximum percentage of cells in S-phase following serum starvation but maintained normal karyotypes. This high proliferation rate, reduction in cell cycle length, and maximum number of cells in S-phase should be very helpful in increasing the efficiency of gene-targeting in pig fetal fibroblasts.

scholarly journals Phase-contrast MRI reveals mechanical behavior of superficial and deep aponeuroses in human medial gastrocnemius during isometric contraction

2008 ◽  
Vol 105 (4) ◽  
pp. 1312-1320 ◽  
Author(s):  
Ryuta Kinugasa ◽  
Dongsuk Shin ◽  
Junichiro Yamauchi ◽  
Chandan Mishra ◽  
John A. Hodgson ◽  
...  
Keyword(s):  
Isometric Contraction ◽  
Phase Contrast ◽  
Muscle Length ◽  
Distal Region ◽  
Voluntary Contraction ◽  
Proximal Region ◽  
Medial Gastrocnemius ◽  
Segment Length ◽  
Cross Sectional ◽  
The Cross

The behavior of the entire medial gastrocnemius (MG) superficial and deep aponeurosis structure was investigated with velocity-encoded phase-contrast, spin-tag, and three-dimensional morphometric magnetic resonance imaging. The displacements and strain of both these aponeuroses, muscle length, and the cross-sectional segment length of the deep aponeurosis were measured during isometric plantarflexion at 20% and 40% of maximal voluntary contraction (MVC). The length of the entire MG shortened during 20% and 40% MVC. All regions of interest in both aponeuroses moved proximally. Positive strain (lengthening) occurred in both ends of the deep aponeurosis and in the proximal region of the superficial aponeurosis. In contrast, negative strain (shortening) was observed in the middle region of the deep aponeurosis and in the distal region of the superficial aponeurosis. Consistent with this shortening of the deep aponeurosis length along the proximal-distal axis was expansion of the aponeuroses in the medial-lateral and anterior-posterior directions in the cross-sectional plane. It is concluded that at low to moderate force levels of isometric contraction, regional differences in strain occur along the proximal-distal axis of both aponeuroses, and some regions of both aponeuroses shorten.

Moxifloxacin Enhances the Antiproliferative and Apoptotic Effects of VP-16 but Inhibits Its Proinflammatory Effects in THP-1 and Jurkat Cells.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 4290-4290
Author(s):  
Ina Fabian ◽  
Debby Haite ◽  
Avital Levitov ◽  
Drora Halperin ◽  
Itamar Shalit
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Cell Cycle Arrest ◽  
Mammalian Cells ◽  
Caspase 3 ◽  
S Phase ◽  
Jurkat Cells ◽  
Cycle Arrest ◽  
Topo Ii ◽  
Number Of Cells

Abstract We previously reported that the fluoroquinolone moxifloxacin (MXF) inhibits NF-kB, mitogen-activated protein kinase activation and the synthesis of proinflammatory cytokines in activated human monocytic cells (AAC48:1974,2004). Since MXF acts on topoisomerase II (Topo II) in mammalian cells, we investigated its effect in combination with another Topo II inhibitor, VP-16, on cell proliferation (by the MTT method), cell cycle, caspase-3 activity and proinflammatory cytokine release in THP-1 and Jurkat cells. THP-1 cells were incubated for 24 h with 0.5–3 μg/ml VP-16 in the presence or absence of 5–20 μg/ml MXF. VP-16 induced a dose dependent decrease in cell proliferation. An additional 2.5-and 1.6-fold decrease in cell proliferation was observed upon incubation of the cells with 0.5 or 1 μg/ml VP-16 and 20 μg/ml MXF, respectively (up to 69% inhibition). To further elucidate the mechanism of the antiproliferative activity of MXF, its effect on cell cycle progression was investigated. In control cultures 1%, 45%,18% and 36% of cells were in G0, G1, S and G2/M phases at 24 h, respectively. In contrast, in cultures treated with 1 μg/ml VP-16 and VP-16+ 20 μg/ml MXF, the number of cells in G1 decreased to 5.4 and 6.5%, respectively, while the number of cells in S phase increased to 25.5 and 42%, respectively and the number of cells in G2/M cells increased to 60 and 44%, respectively. These data provide evidence for S-G2/M cell cycle arrest induced by VP-16 and that addition of MXF shifted the S-G2/M arrest more towards the S phase. Since the antiproliferative effects of MXF could also be attributed to apoptotic cell death in addition to cell cycle arrest, we investigated the effect of the drugs on apoptosis. Using the fluorogenic assay for caspse-3 activity, we show that incubation of THP-1 cells for 6 h with 1.5 μg/ml VP-16 resulted in 630±120 unit/50μg protein of caspase-3 activity while the combination of 1.5 μg/ml VP-16 and 20 μg/ml MXF enhanced caspase-3 activity up to 1700±340 units/50μg protein (vs.233±107 in control cells), indicating that MXF synergises with VP-16 in activation of caspase-3. In Jurkat cells, the addition of 0.5 or 1 μg/ml VP-16, did not affect cell proliferation while in the presence of 20 μg/ml MXF and 1 μg/ml VP-16 there was a 62% decrease in cell proliferation (p&lt;0.05). Exposure of Jurkat cells to 3 μg/ml VP-16 alone resulted in 504±114 units/50μg protein of caspase-3 activity and the addition of 20μg/ml MXF enhanced caspase-3 activity up to 1676± 259 units/50μg protein (vs 226±113 units/50μg protein in control cells). We further examined pro-inflammatory cytokine secretion upon stimulation of THP-1 cells with VP-16, MXF or their combination. VP-16 alone at 3 μg/ml increased IL-8 and TNF-α secretion from THP-1 cells by 2.5 and 1.8-fold respectively. Addition of MXF (5–20 μg/ml) inhibited the two cytokines secretion by 72–77% and 58–72%, respectively. The above combined data indicate that MXF, at clinically attainable concentrations, demonstrates pronounced synergistic effect with VP-16 as an anti-proliferative agent mainly by enhancing caspase-3 activity and apoptosis. At the same time MXF inhibits the pro-inflammatory effects conferred by VP-16 in the tumor cells studied. The clinical significance of the above anti-proliferative and anti-inflammatory effects of MXF in combination with VP-16 should be further investigated in animal models.

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