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Endothelial cells lining blood vessels are essential for maintaining vascular homeostasis and mediate several pathological and physiological processes. Mechanical stresses generated by blood flow and other biomechanical factors significantly affect endothelial cell activity. Here, we review how mechanical stresses, both in situ and in vitro, affect endothelial cells. We review the basic principles underlying the cellular response to mechanical stresses. We also consider the implications of these findings for understanding the mechanisms of mechanotransducer and mechano-signal transduction systems by cytoskeletal components. [ABSTRACT FROM AUTHOR]

Electrical stimulation of the cell can have a number of different effects depending on the type of cell being stimulated. In general, electrical stimulation can cause the cell to become more active, increase its metabolism, and change its gene expression. For example, if the electrical stimulation is of low intensity and short duration, it may simply cause the cell to depolarize. However, if the electrical stimulation is of high intensity or long duration, it may cause the cell to become hyperpolarized. The electrical stimulation of cells is a process by which an electrical current is applied to cells in order to change their function or behavior. This process can be used to treat various medical conditions and has been shown to be effective in a number of studies. In this perspective, the effects of electrical stimulation on the cell are summarized. [ABSTRACT FROM AUTHOR]

Electrical stimulation of the skin and muscles, e.g., in the fields of rehabilitation medicine and acupuncture, is known to locally increase blood flow and metabolism, and thus have beneficial health effects. However, little is known about the changes in cellular morphology or regulation of the localization of specific proteins in response to electrical stimuli. The present study was performed to examine the effects of electrical stimulation on the cytoskeletal system of cultured fibroblasts. Following application of electrical stimulation to cultured fibroblastic cells for a period of about 2 h, the stress fibers in the cells became thicker and the cells showed a contracted appearance. Cells were subjected to periodic electrical stimulation for 0 (unstimulated control), 2, 5, or 20 h. The stress fibers showed an increase in thickness within 2 h, and became gradually thicker until 20 h. In addition, the focal adhesions and stress fibers were enlarged after 2 h of continuous stimulation, and both stress fibers and focal adhesions became larger and thicker after 20 h of periodic stimulation. Cells showed increased staining of focal adhesions with anti-phosphotyrosine antibody (PY-20) after electrical stimulation. Cells also showed increased staining of tyrosine-phosphorylated focal adhesion kinase (FAK) (pY397) and tyrosine-phosphorylated c-Src (pY418), indicating that electrical stimulation affected signal transduction-related proteins. [ABSTRACT FROM AUTHOR]

Stimulation of the skin and muscles in the field of acupuncture and moxibustion has been shown to increase local blood flow and metabolism or maintain the body in a sustained healthy state. However, little is known about cellular structural changes in response to the electrical stimulus or how the localization of specific proteins is regulated by such stimulation. Cultured fibroblasts were subject to periodic electrical stimulation for 0 min (the unstimulated control), 2 h, 5 h, and 20 h. After 2 h, cell stress fibers and focal adhesions became enlarged, and the stress fibers exhibited an increase in thickness. Within 20 h of periodic stimulation, both the stress fibers and focal adhesions gradually became larger and thicker. An anti-phosphotyrosine antibody (PY-20) was used to stain the cells after electrical stimulations, which showed the increased staining of focal adhesions. They also exhibited the increased staining of the active form of a focal adhesion kinase (FAK) (pY397) and c-Src (pY418), indicating that electrical stimulation had affected certain proteins associated with signal transduction. An ELISA analysis showed that 20 h of electrical stimulation gradually increased the amount of the active form of c-Src until it was approximately tripled, whereas 5 h of electrical stimulation approximately doubled the amount of the active form of FAK, this being the maximum reached. These findings indicate that electrical stimulation stimulates the activity of c-Src and FAK signaling proteins and alters the structure of the actin cytoskeleton and focal adhesions. [ABSTRACT FROM AUTHOR]

Src protein tyrosine kinases (SFKs) are a family of nonreceptor tyrosine kinases that are localized beneath the plasma membrane and are activated during cell adhesion, migration, and elongation. Due to their involvement in the activation of signal transduction cascades, SFKs have been suggested to play important roles in the determination of cell polarity during cell extension and elongation. However, the mechanism underlying Src-mediated polarity formation remains unclear. The present study was performed to investigate the mechanisms underlying Src-induced cell polarity formation and cell elongation using Src knockout fibroblasts (SYFs) together with an inhibitor of Src. Normal and Src knockout fibroblasts were also transfected with a wild-type c-Src, dominant negative c-Src, or constitutively active c-Src gene to analyze the changes in cell morphology. SYF cells cultured on a glass substrate elongated symmetrically into spindle-shaped cells, with the formation of focal adhesions at both ends of the cells. When normal fibroblasts were treated with Src Inhibitor No. 5, a selective inhibitor of Src tyrosine kinases, they elongated into symmetrical spindle-shaped cells, similar to SYF cells. These results suggest that cell polarity during extension and elongation may be regulated by SFKs and that the expression and regulation of Src are important for the formation of polarity during cell elongation. [ABSTRACT FROM AUTHOR]

The present study aims to investigate the composition including concentrations of IGF-1, IgG and Vit A in colostrum and their effects by litter size and goat parity in 3 groups of goats; Black Bengal (BB), Saanen (SA) and their crossbred (BBSA). Thirty-eight goats were used (23 BB, 7 BBSA and 8 SA). The composition (fat, protein, lactose and total solid; TS) in colostrum (Day 0; D0) and milk (Day 4; D4 and Day 7; D7) were measured. The IGF-1, IgG concentrations were analysed in some samples collected at D0, D4 and D7 while Vit A was analysed only in colostrum. The results showed that colostrum components were similar among experimental groups. However, the colostral IGF-1 concentration of BBSA (983.0 ± 163.6 ng/mL) was higher than that of BB (340.7 ± 85.5 ng/mL, p < 0.01) and SA (417.1 ± 93.9 ng/mL, p < 0.01). The colostral IgG concentration of BB (8.2 ± 0.9 mg/mL) was lower than that of BBSA (12.9 ± 1.7 mg/mL, p < 0.05) and SA (12.9 ± 1.0 mg/mL, p < 0.01). Colostral Vit A concentration in BBSA (787.2 ± 152.6 µg/100 gm) was higher than that in BB (388.9 ± 84.3 µg/100 gm, p < 0.05) but was not different from SA (522.8 ± 96.9 µg/100 gm). Colostrum from all groups contained higher protein and TS but was lower in lactose concentration than milk. The IGF-1 and IgG concentrations in colostrum were much higher than in milk both D4 and D7 ( p < 0.001). Additionally, litter size had no effects on colostrum contents but colostrum from goats with a higher parity number had higher IgG concentration. It is concluded that colostrum from BBSA may be superior when fed to BB newborn goats in terms of higher IGF-1, IgG and Vit A contents. Moreover, colostrum from goats with a high parity number contained more IgG content.

Fibroblastic cells show specific substrate selectivity for typical cell-substrate adhesion. However, focal adhesion kinase (FAK) contributes to controlling the regulation of orientation and polarity. When fibroblasts attach to micropatterns, tyrosine-phosphorylated proteins and FAK are both detected along the inner border between the adhesive micropatterns and the nonadhesive glass surface. FAK likely plays important roles in regulation of cell adhesion to the substrate, as FAK is a tyrosine-phosphorylated protein that acts as a signal transduction molecule at sites of cell-substrate attachment, called focal adhesions. FAK has been suggested to play a role in the attachment of cells at adhesive micropatterns by affecting cell polarity. Therefore, the localization of FAK might play a key role in recognition of the border of the cell with the adhesive micropattern, thus regulating cell polarity and the cell axis. This review discusses the regulation and molecular mechanism of cell proliferation and cell elongation by FAK and its associated signal transduction proteins., Competing Interests: There are no conflicts of interest associated with this manuscript.

As conventional fluorescence microscopy and confocal laser scanning microscopy generally produce images with blurring at the upper and lower planes along the z -axis due to non-focal plane image information, the observation of biological images requires "deconvolution." Therefore, a microscope system's individual blur function (point spread function) is determined theoretically or by actual measurement of microbeads and processed mathematically to reduce noise and eliminate blurring as much as possible. Here the author describes the use of open-source software and open hardware design to build a deconvolution microscope at low cost, using readily available software and hardware. The advantage of this method is its cost-effectiveness and ability to construct a microscope system using commercially available optical components and open-source software. Although this system does not utilize expensive equipment, such as confocal and total internal reflection fluorescence microscopes, decent images can be obtained even without previous experience in electronics and optics.