Temperature changes in superficial and deep tissue layers with respect to time of cold gel pack application in dogs

Despite the widespread clinical use of cryotherapy, there is only limited and inconsistent data on application times. The aim of this study was to determine the changes in tissue temperature and the duration of this effect. In this experimental study, five adult dogs were used. A cold gel pack (10 x 20 cm) was applied transversally over the right leg femoral region. Temperatures were recorded simultaneously: rectal by a mercury thermometer; right leg skin by probe of Nihon Kohden 6000 polygraph; and right leg subcutaneous, intramuscular, and periosteal, and left leg intramuscular temperatures by a fluorooptic biomedical fiber optic (0.6 mm diameter) thermometer connected to a computer system. Total system accuracy was 0.01 degrees C. Cold gel packs were applied for 10, 15, 20, 25, and 30 minutes duration. The results can be summarized as cooling and rewarming data. 1) The superficial tissues such as skin and subcutaneous demonstrated the most rapid and profound cooling effect. The deeper tissues such as bone and muscle exhibited a smaller and more gradual decline in temperature. 2) There was a prolonged rewarming period in all tissues after the removal of the cold gel pack but this period was longer in deeper tissues. According to cold gel pack application time, the rewarming time in intramuscular layers to baseline or plateau temperatures was about: 60 +/- 3 minutes for 10 minutes application, 100 +/- 4 for 15, 130 +/- 5 for 20, 140 +/- 7 for 25, and 145 +/- 8 for 30. It can be concluded from these results that with increased cold gel pack application time, deep tissue temperature decreased and the duration of cooling effect increased. However, the data indicated that the length of application time and the duration of cooling effect were not linearly related. Especially after 20 minutes of application this ratio decreased progressively. There may be implications of these results for clinical practice.

The 50 Hz (10 mT) sinusoidal magnetic field: effects on stress-related behavior of rats

PURPOSE

The purpose of this study was to investigate the behavioral changes induced by 50 Hz, 10 mT flux density Sinusoidal Magnetic Field (MF).

MATERIAL AND METHODS

Seventy-six young adult male Wistar albino rats were used in the study. They were separated into two groups: control group (C) n=38; MF group n=38. C animals were left under the same conditions with the MF group for 21 days but with prevented or avoided exposure to MF. Anxiety and stress-related behavioral changes were investigated by elevated plus-maze and hole-board systems. Just before being tested in the maze, each animal was tested by means of the hole-board method in order to separate the directed exploration behavior and locomotion activity changes from anxiety-related behavior.

RESULTS

In the hole-board system parameters there were no statistically significant differences between the two groups. There was a statistically significant difference between MF and C groups when the ratio of time spent on open arms to the total time spent on all arms was evaluated (0.12±0.08 and 0.34±0.18 respectively and p <0.01).

CONCLUSION

Our results suggest that after 21 days, a continuous exposure to extremely low frequency of magnetic field (50 Hz, 10 mT) has no significant effect on activity and exploration activity but significantly induces stress and anxiety-related behavior in rats (Tab. 2, Fig. 9, Ref. 19).

Metformin represses the carcinogenesis potentially induced by 50 Hz magnetic fields in aged mouse fibroblasts via inhibition of NF-kB

Aging is a risk factor for various human disorders, including cancer. Current literature advocates that the primary principles of aging depend on the endogenous stress-induced DNA damage caused by reactive oxygen species 50 Hz low-frequency magnetic field was suggested to induce DNA damage and chromosomal instability. NF-kB, activated by DNA damage, is upregulated in age-related cancers and inhibition of NF-kB results in aging-related delayed pathologies. Metformin (Met), an NF-kB inhibitor, significantly reduces both NF-kB activation and expression in aging and cancer. This in vitro study, therefore, was set out to assess the effects of 5mT MF in 50 Hz frequency and Met treatment on the viability and proliferation of aged mouse NIH/3T3 fibroblasts and expression of RELA/p65, matrix metalloproteinases MMP2 and MMP9, and E-cadherin (CDH1) genes. The trypan blue exclusion assay was used to determine cell viability and the BrdU incorporation assay to determine cell proliferation. The MMP-2/9 protein analysis was carried out by immunocytochemistry, NF-kB activity by ELISA and the expressions of targeted genes by qRT-PCR methods. Four doses of Met (500 uM, 1 mM, 2 mM and 10 mM) suppressed both the proliferation and viability of fibroblasts exposed to the MF in a dose-dependent pattern, and the peak inhibition was recorded at the 10 mM dose. Met reduced the expression of NF-kB, and MMP2/9, elevated CDH1 expression and suppressed NF-kB activity. These findings suggest that Met treatment suppresses the carcinogenic potential of 50 Hz MFs in aged mouse fibroblasts, possibly through modulation of NF-kB activation and epithelial-mesenchymal transition modulation.

Assessing the effect of selenium on cyclin D1 level and nuclear factor kappa b activity in NIH/3T3 fibroblast cells at 2100 MHz electromagnetic field exposure

Although there are numerous studies on the health impacts of electromagnetic field (EMF) of mobile phone operation frequency 2100 MHz, the published works present contradicting results. Long-term exposure to mobile phone frequencies has unclear health hazards. Therefore, it is important to investigate the molecular mechanism of possible biological effects in mobile phone exposure and to determine the corresponding biological markers. Towards this end, this study was designed to assess the effect of 200 nM selenium (Se) on cell viability% [trypan blue], cell cycle biomarker [cyclin D1] and the transcription factor [nuclear factor kappa b (NF-κB)] in NIH/3T3 fibroblast cells when exposed to 2100 MHz mobile phone frequency. When 2100 MHz EMF was exposed to NIH/3T3 fibroblast cells, the cell viability% was reduced, whereas cyclin D1 level and NF-kB activity increased. Also we show that Se supplementation decreases the effects of 2100 MHz EMF on these parameters. Although future studies will be required to investigate the biological effects of EMF emitted by mobile phones, the results obtained here provide an insight into the molecular mechanisms and specifically underlying selenium's protective effect against 2100 MHz EMF exposure.

Zinc affects nuclear factor kappa b and DNA methyltransferase activity in C3H cancer fibroblast cells induced by a 2100 MHz electromagnetic field

The use of mobile phones is becoming widespread with the development of technology, and as a result, its effects on human health are becoming more and more important every day. Studies have reported that the electromagnetic field (EMF) emitted by mobile phones may have adverse effects on the biological systems. In order to evaluate the effect of zinc (Zn) on C3H cancer fibroblast cells exposed to 2100 MHz EMF, we analyzed cell viability%, nuclear factor kappa b (NF-κB) and DNA methyltransferase (DNMT) activities. Cells were divided to following groups: Control, sham control, 2100 MHz EMF, 50 µM Zn + 2100 MHz EMF, 100 µM Zn + 2100 MHz EMF, and 200 µM Zn + 2100 MHz EMF for 2 h. We measurement cell viability, NF-κB and DNMT activities. There was increased cell viability % in the 2100 MHz EMF group compared to the control group, while the cell viability % was decreased in the 50, 100 and 200 µM Zn + 2100 MHz EMF groups compared to 2100 MHz EMF. NF-κB and DNMT activities were a significant increase in the 2100 MHz EMF group compared to the control group, although were statistically decreased in the 50, 100 and 200 µM Zn + 2100 MHz EMF groups compared to the 2100 MHz EMF group. Our results demonstrate that 2100 MHz EMF exposure in cancer fibroblast cells induce NF-κB and DNMT activities, whereas zinc supplementation reduce NF-κB and DNMT activities-induced 2100 MHz EMF.