Effects of electromagnetic field (1.8/0.9 GHz) exposure on growth plate in growing rats

Adverse effects of 900, 1800 and 2100 MHz radiofrequency radiation emitted from mobile phones on bone and skeletal muscle

The goal of this study was to biomechanically and morphologically research both the impact of mobile phone like radiofrequency radiations (RFR) on the tibia and the effects on skeletal muscle through oxidative stress parameters. Fifty-six rats (200-250 g) were put into groups: healthy sham (n = 7), healthy RFR (900, 1800, 2100 MHz) (n = 21), diabetic sham (n = 7) and diabetic RFR (900, 1800, 2100 MHz) (n = 21). Over a month, each group spent two hours/day in a Plexiglas carousel. The rats in the experimental group were exposed to RFR, but the sham groups were not. At the end of the experiment, the right tibia bones and skeletal muscle tissue were removed. The three-point bending test and radiological evaluations were performed on the bones, and CAT, GSH, MDA, and IMA in muscles were measured. There were differences in biomechanics properties and radiological evaluations between the groups (p < .05). In the measurements in the muscle tissues, significant differences were statistically found (p < .05). The average whole-body SAR values for GSM 900, 1800 and 2100 MHz were 0.026, 0.164, and 0.173 W/kg. RFRs emitted from mobile phone may cause adverse effects on tibia and skeletal muscle health, though further studies are needed.

Effects of Electrical Stimulation on Articular Cartilage Regeneration with a Focus on Piezoelectric Biomaterials for Articular Cartilage Tissue Repair and Engineering

There is increasing evidence that chondrocytes within articular cartilage are affected by endogenous force-related electrical potentials. Furthermore, electrical stimulation (ES) promotes the proliferation of chondrocytes and the synthesis of extracellular matrix (ECM) molecules, which accelerate the healing of cartilage defects. These findings suggest the potential application of ES in cartilage repair. In this review, we summarize the pathogenesis of articular cartilage injuries and the current clinical strategies for the treatment of articular cartilage injuries. We then focus on the application of ES in the repair of articular cartilage in vivo. The ES-induced chondrogenic differentiation of mesenchymal stem cells (MSCs) and its potential regulatory mechanism are discussed in detail. In addition, we discuss the potential of applying piezoelectric materials in the process of constructing engineering articular cartilage, highlighting the important advances in the unique field of tissue engineering.

Non-Ionizing Radiation Created by Mobile Phone Progresses Endometrial Hyperplasia: An Experimental Rat Study

BACKGROUND

Non-ionizing radiation is related with many pathologies.

AIM

Determine association between non-ionizing radiation and endometrial hyperplasia.

METHODS

Fifty oopherectomized Wistar albino rats were administered Estradiol hemihydrate (4 mg/kg) to induce hyperplasia, and were exposed to 1800 MHz radiation created by a mobile phone and a signal generator working as base station. This study was carried out with 5 groups in two phases. The study groups were. Control group without any exposure; group receiving estrogen in first phase of the study; group receiving estrogen in both phases; group receiving estrogen in the first phase and exposed to non-ionizing radiation during second phase and group taking estrogen in both phases and exposed to non-ionizing radiation during the second phase. Following both phases, uterine horns were excised and evaluated based on glandular density (GD), epithelial cell height (ECH), and luminal epithelial cell height (LECH).

RESULTS

Estrogen increased all parameters during both phases (LECH, GD, and ECH values were 12,2 vs. 16,5 (p = 0.001), 34 vs. 47 (p <0.001), and 201 vs. 376.6 (p = 0.001), respectively during the first phase; LECH, GD and ECH values were 13,2 vs. 20,3 (p <0.001), 35.5 vs. 65,5 (p <0.001), 219.9 vs. 419.6 (p <0.001), respectively, during the second phase).Non-ionizing radiation increased all values without estrogen exposure (LECH, GD and ECH values were 13,2 vs. 17,2 (p = 0,074), 35,5 vs. 59 (p = 0.074), and 219 vs. 318.3 (p <0.001), respectively) or with estrogen exposure (LECH, GD, and ECH, values were 20,3 vs. 22,8 (p = 0,168), 65,5 vs. 77 (p = 0,058), and 419,6 vs. 541,6 (p = 0.004), respectively).

CONCLUSION

Non-ionizing radiation progressed endometrial hyperplasia in an experimental rat model with/without estrogen exposure.

Biophysical Stimuli: A Review of Electrical and Mechanical Stimulation in Hyaline Cartilage

OBJECTIVE

Hyaline cartilage degenerative pathologies induce morphologic and biomechanical changes resulting in cartilage tissue damage. In pursuit of therapeutic options, electrical and mechanical stimulation have been proposed for improving tissue engineering approaches for cartilage repair. The purpose of this review was to highlight the effect of electrical stimulation and mechanical stimuli in chondrocyte behavior.

DESIGN

Different information sources and the MEDLINE database were systematically revised to summarize the different contributions for the past 40 years.

RESULTS

It has been shown that electric stimulation may increase cell proliferation and stimulate the synthesis of molecules associated with the extracellular matrix of the articular cartilage, such as collagen type II, aggrecan and glycosaminoglycans, while mechanical loads trigger anabolic and catabolic responses in chondrocytes.

CONCLUSION

The biophysical stimuli can increase cell proliferation and stimulate molecules associated with hyaline cartilage extracellular matrix maintenance.