The effect of prenatal exposure to 1800 MHz electromagnetic field on calcineurin and bone development in rats

Does Microwave Exposure at Different Doses in the Pre/Postnatal Period Affect Growing Rat Bone Development?

Effects of pre/postnatal 2.45 GHz continuous wave (CW), Wireless-Fidelity (Wi-Fi) Microwave (MW) irradiation on bone have yet to be well defined. The present study used biochemical and histological methods to investigate effects on bone formation and resorption in the serum and the tibia bone tissues of growing rats exposed to MW irradiation during the pre/postnatal period. Six groups were created: one control group and five experimental groups subjected to low-level different electromagnetic fields (EMF) of growing male rats born from pregnant rats. During the experiment, the bodies of all five groups were exposed to 2.45 GHz CW-MW for one hour/day. EMF exposure started after fertilization in the experimental group. When the growing male rats were 45 days old in the postnatal period, the control and five experimental groups' growing male and maternal rats were sacrificed, and their tibia tissues were removed. Maternal rats were not included in the study. No differences were observed between the control and five experimental groups in Receptor Activator Nuclear factor-kB (RANK) biochemical results. In contrast, there was a statistically significant increase in soluble Receptor Activator of Nuclear factor-kB Ligand (sRANKL) and Osteoprotegerin (OPG) for 10 V/m and 15 V/m EMF values. Histologically, changes in the same groups supported biochemical results. These results indicate that pre/postnatal exposure to 2.45 GHz EMF at 10 and 15 V/m potentially affects bone development.

Effects of prenatal acetaminophen exposure at different stages, doses and courses on articular cartilage of offspring mice

Previous studies showed that chondrodysplasia has intrauterine origin. Although prenatal acetaminophen exposure (PAcE) can cause nervous and reproductive abnormalities in offspring, its effect on cartilage is uninvestigated. Herein, mice were treated with different doses and courses of acetaminophen at various gestational stages (100 or 400 mg/kg∙d on gestational days 10-12 (GD10-12), 400 mg/kg∙d on GD12 or GD15-17) based on clinical administration and conversion between humans and mice. Fetal knee joints were harvested on GD18 to analyze cartilage morphology, chondrocyte proliferation and apoptosis, and matrix content, synthesis and degradation. Results showed that 400 mg/kg∙d acetaminophen exposure during GD10-12 decreased chondrocyte numbers, safranin O staining, proliferation and matrix synthesis, without elevating matrix degradation and apoptosis. Low-dose, single-course, or late-pregnancy exposure had no effect on above indexes. Moreover, Tgfβ pathway was inhibited, showing a positive correlation with the expression of Col2a1, Acan, Ki67, and Pcna. Overall, clinical doses of PAcE can inhibit chondrocyte proliferation and matrix synthesis, causing fetal mice chondrodysplasia, especially after multi-course exposure of 400 mg/kg∙d acetaminophen during GD10-12, the mechanism of which might involve Tgfβ pathway inhibition. This study provides an experimental basis for assessing fetal developmental toxicity and standardizing the clinical use of acetaminophen during pregnancy.

A novel implant surface modification mode of Fe3O4-containing TiO2 nanorods with sinusoidal electromagnetic field for osteoblastogenesis and angiogenesis

Implants made of Ti and its alloys are widely utilized in orthopaedic surgeries. However, insufficient osseointegration of the implants often causes complications such as aseptic loosening. Our previous research discovered that disordered titanium dioxide nanorods (TNrs) had satisfactory antibacterial properties and biocompatibility, but TNrs harmed angiogenic differentiation, which might retarded the osseointegration process of the implants. Magnetic nanomaterials have a certain potential in promoting osseointegration, electromagnetic fields within a specific frequency and intensity range can facilitate angiogenic and osteogenic differentiation. Therefore, this study used Fe₃O₄ to endow magnetism to TNrs and explored the regulation effects of Ti, TNrs, and Fe₃O₄-TNrs under 1 ​mT 15 ​Hz sinusoidal electromagnetic field (SEMF) on osteoblastogenesis, osseointegration, angiogenesis, and its mechanism. We discovered that after the addition of SEMF treatment to VR-EPCs cultured on Fe₃O₄-TNrs, the calcineurin/NFAT signaling pathway was activated, which then reversed the inhibitory effect of Fe₃O₄-TNrs on angiogenesis. Besides, Fe₃O₄-TNrs with SEMF enhanced osteogenic differentiation and osseointegration. Therefore, the implant modification mode of Fe₃O₄-TNrs with the addition of SEMF could more comprehensively promote osseointegration and provided a new idea for the modification of implants.

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.

The effects of long-term prenatal exposure to 900, 1800, and 2100 MHz electromagnetic field radiation on myocardial tissue of rats

It is well-known that wireless communication technologies facilitate human life. However, the harmful effects of electromagnetic field (EMF) radiation on the human body should not be ignored. In the present study, we evaluated the effects of long-term, prenatal exposure to EMF radiation on the myocardium of rats at varying durations. Overall, 18 pregnant Sprague-Dawley rats were assigned into six groups (n = 3 in each group). In all groups other than the control group, three pregnant rats were exposed to EMF radiation (900, 1800 and 2100 MHz) for 6, 12 and 24 h over 20 days. After delivery, the newborn male pups were identified and six newborn male pups from each group were randomly selected. Then, histopathological and biochemical analysis of myocardial samples were performed. When 24-h/day prenatal exposures to 900, 1800, 2100 MHz EMF radiation were evaluated, myocardial damage was greater in the 2100 MHz EMF-24h group than the other groups. In addition, when malondialdehyde (MDA) and glutathione (GSH) levels associated with reactive oxidative species (ROS) were evaluated, the MDA level was higher in the 2100 MHz EMF-24h group compared with the other groups. The GSH level was also lower in the 2100 MHz EMF-24h group. When the 6, 12 and 24 h/day prenatal exposures to 1800 MHz EMF radiation were evaluated, myocardial damage was greater in 1800 MHz EMF-24h group than the remaining groups (p < 0.0001). Also, MDA level was greater in the 1800 MHz EMF-24h group compared with the other groups while the GSH level was lower in this group. It was shown that myocardial tissue was affected more by long-term exposure to EMF radiation at high frequencies. The data raise concerns that the harmful effects of non-ionizing radiation exposure on cardiac tissue will increase with 5G technology.

3.5-GHz radiofrequency electromagnetic radiation promotes the development of Drosophila melanogaster

With the rapidly increasing popularity of 5G mobile technology, the effect of radiofrequency radiation on human health has caused public concern. This study explores the effects of a simulated 3.5 GHz radiofrequency electromagnetic radiation (RF-EMF) environment on the development and microbiome of flies under intensities of 0.1 W/m², 1 W/m² and 10 W/m². We found that the pupation percentages in the first 3 days and eclosion rate in the first 2 days were increased under exposure to RF-EMF, and the mean development time was shortened. In a study on third-instar larvae, the expression levels of the heat shock protein genes hsp22, hsp26 and hsp70 and humoral immune system genes AttC, TotC and TotA were all significantly increased. In the oxidative stress system, DuoX gene expression was decreased, sod2 and cat gene expression levels were increased, and SOD and CAT enzyme activity also showed a significant increase. According to the 16S rDNA results, the diversity and species abundance of the microbial community decreased significantly, and according to the functional prediction analysis, the genera Acetobacter and Lactobacillus were significantly increased. In conclusion, 3.5 GHz RF-EMF may enhance thermal stress, oxidative stress and humoral immunity, cause changes in the microbial community, and regulate the insulin/TOR and ecdysteroid signalling pathways to promote fly development.

The role of Ca2+ /Calcineurin/NFAT signalling pathway in osteoblastogenesis

The bone remodelling process is closely related to bone health. Osteoblasts and osteoclasts participate in the bone remodelling process under the regulation of various factors inside and outside. Excessive activation of osteoclasts or lack of function of osteoblasts will cause occurrence and development of multiple bone‐related diseases. Ca²⁺/Calcineurin/NFAT signalling pathway regulates the growth and development of many types of cells, such as cardiomyocyte differentiation, angiogenesis, chondrogenesis, myogenesis, bone development and regeneration, etc. Some evidences indicate that this signalling pathway plays an extremely important role in bone formation and bone pathophysiologic changes. This review discusses the role of Ca²⁺/Calcineurin/NFAT signalling pathway in the process of osteogenic differentiation, as well as the influence of regulating each component in this signalling pathway on the differentiation and function of osteoblasts, whereby the relationship between Ca²⁺/Calcineurin/NFAT signalling pathway and osteoblastogenesis could be deeper understood.

Simulated mobile communication frequencies (3.5 GHz) emitted by a signal generator affects the sleep of Drosophila melanogaster

With the rapid development of science and technology, 5G technology will be widely used, and biosafety concerns about the effects of 5G radiofrequency radiation on health have been raised. Drosophila melanogaster was selected as the model organism for our study, in which a 3.5 GHz radiofrequency radiation (RF-EMR) environment was simulated at intensities of 0.1 W/m², 1 W/m², and 10 W/m². The activity of parent male and offspring (F1) male flies was measured using a Drosophila activity monitoring system under short-term and long-term 3.5 GHz RF-EMR exposure. Core genes associated with heat stress, the circadian clock and neurotransmitters were detected by QRT-PCR technology, and the contents of GABA and glutamate were detected by UPLC-MS. The results show that short-term RF-EMR exposure increased the activity level and reduced the sleep duration while long-term RF-EMR exposure reduced the activity level and increased the sleep duration of F1 male flies. Under long-term RF-EMR, the expression of heat stress response-related hsp22, hsp26 and hsp70 genes was increased, the expression of circadian clock-related per, cyc, clk, cry, and tim genes was altered, the content of GABA and glutamate was reduced, and the expression levels of synthesis, transport and receptor genes were altered. In conclusion, long-term RF-EMR exposure enhances the heat stress response of offspring flies and then affects the expression of circadian clock and neurotransmitter genes, which leads to decreased activity, prolonged sleep duration, and improved sleep quality.

Development of health-based exposure limits for radiofrequency radiation from wireless devices using a benchmark dose approach

BACKGROUND

Epidemiological studies and research on laboratory animals link radiofrequency radiation (RFR) with impacts on the heart, brain, and other organs. Data from the large-scale animal studies conducted by the U.S. National Toxicology Program (NTP) and the Ramazzini Institute support the need for updated health-based guidelines for general population RFR exposure.

OBJECTIVES

The development of RFR exposure limits expressed in whole-body Specific Absorption Rate (SAR), a metric of RFR energy absorbed by biological tissues.

METHODS

Using frequentist and Bayesian averaging modeling of non-neoplastic lesion incidence data from the NTP study, we calculated the benchmark doses (BMD) that elicited a 10% response above background (BMD₁₀) and the lower confidence limits on the BMD at 10% extra risk (BMDL₁₀). Incidence data for individual neoplasms and combined tumor incidence were modeled for 5% and 10% response above background.

RESULTS

Cardiomyopathy and increased risk of neoplasms in male rats were the most sensitive health outcomes following RFR exposures at 900 MHz frequency with Code Division Multiple Access (CDMA) and Global System for Mobile Communications (GSM) modulations. BMDL₁₀ for all sites cardiomyopathy in male rats following 19 weeks of exposure, calculated with Bayesian model averaging, corresponded to 0.27-0.42 W/kg whole-body SAR for CDMA and 0.20-0.29 W/kg for GSM modulation. BMDL₁₀ for right ventricle cardiomyopathy in female rats following 2 years of exposure corresponded to 2.7-5.16 W/kg whole-body SAR for CDMA and 1.91-2.18 W/kg for GSM modulation. For multi-site tumor modeling using the multistage cancer model with a 5% extra risk, BMDL₅ in male rats corresponded to 0.31 W/kg for CDMA and 0.21 W/kg for GSM modulation.

CONCLUSION

BMDL₁₀ range of 0.2-0.4 W/kg for all sites cardiomyopathy in male rats was selected as a point of departure. Applying two ten-fold safety factors for interspecies and intraspecies variability, we derived a whole-body SAR limit of 2 to 4 mW/kg, an exposure level that is 20-40-fold lower than the legally permissible level of 0.08 W/kg for whole-body SAR under the current U.S. regulations. Use of an additional ten-fold children's health safety factor points to a whole-body SAR limit of 0.2-0.4 mW/kg for young children.

Investigation into the effects of static and electric fields on bone healing process: An experimental tibial fracture model study in Wistar-Albino male rats

OBJECTIVE:

In this experimental study, we aimed to investigate whether 0 Hz-Static and 50 Hz-Electric fields have an effect on bone healing.

METHODS:

In this study, 45 male Wistar-Albino rats were equally and randomly separated into three groups as follows: a 0 Hz-Static electric field (SEF), a 50-Hz low-frequency electric field (LFEF) and a control group. A manual fracture was performed in the left tibia diaphysis of all rats, and fractures were fixed using circular plaster over the knee. The LFEF group was exposed to 50 Hz electric field for 30 minutes a day, five days a week, for a total of eight weeks. The SEF group was exposed to 0 Hz electric field within the same time interval. The control group was held in identical environmental conditions, without exposure to electric field. Periodic radiographs were taken from all the animals. At the end of this study, rats were sacrificed and mechanical/histopathologic examinations were performed.

RESULTS:

Radiologic, mechanical and histologic scores of the LFEF group were lower than those of the SEF and control groups; however, no significant difference was found in group comparisons in terms of average histologic and radiologic scores (p>0.05).

CONCLUSION:

Results extracted from the current study suggest that 0-hz static and 50-hz electric field exposures affect bone healing tissue of tibial fracture models in rats, although it is not significant.

Morphological changes in the vertebrae and central canal of rat pups born after exposure to the electromagnetic field of pregnant rats

Several studies have investigated the effects of the electromagnetic field (EMF) on the central nervous system. However, we encountered no studies of the effects of EMF applied in the prenatal period on the offspring vertebrae. The aim of this study is to investigate the effect of a 900 megahertz (MHz) EMF applied to rat dams in the prenatal period on the vertebrae of rat pups. Female Sprague Dawley rats weighing 180-250 g were used in the experiment. Rats identified as pregnant were divided into two groups, control (n = 3) and EMF (n = 3). No EMF was applied to the control group pregnant rats. EMF was applied to the EMF group rats for 1 h daily on an equal and standard basis on prenatal days 13-21. All newborn rat pups were divided into pup control (n = 6) (PC) and pup EMF (n = 6) (PEMF) groups, and no treatment was performed on either. All animals were decapitated on day 32, and the spinal cord in the upper thoracic region was harvested. Vertebral tissues were subjected to routine histological procedures. Histopathological examination revealed that PEMF group vertebral cartilage had been converted into bone tissue. Comparison of central canal diameter and area values between the PEMF group and the PC group revealed statistically significant increases in the PEMF group (p = 0.000 and p = 0.001, respectively). Statistical analysıs revealed no significant difference in mean body weights between the two groups (p > 0.530). Based on these findings, we think that 900 MHz EMF applied in the prenatal period affects the development of the vertebrae. This effect causes pathological changes in the rat pup vertebrae. These findings now raise the question of whether EMF also has an impact on neurological and neurosurgical diseases involving the vertebrae.

The Effect of Prenatal Exposure to 2.4 GHz Radio Frequency on the Histology and Expression of the osteocalcin and RUNX2 Gene of the Forelimb in an NMRI Mouse

Introduction: Today the use of electromagnetic waves has dramatically increased in modern industrial societies. This study aimed to investigate the effect of prenatal exposure to 2.4 GHz wireless frequency on forelimb development in an NMRI mouse in vivo. Methods: A total of 21 female mice weighing 25-30 g were included in the present study. They were randomly assigned to 3 groups, namely control (n=7), sham (n=7), and experimental (n=7). After mating, the experimental group was exposed to 2.4 GHz radio frequency at a distance of 20-30 cm from the device, 4 h/d until the delivery. The sham group was placed at a distance of 20-30 cm from the device every day without exposure to electromagnetic waves, and the control group had a pregnancy period without any stress and electromagnetic wave exposure. After giving birth, the forelimbs were isolated from the infants and examined by stereological studies and RT-PCR for the evaluation of osteocalcin and RUNX2 gene expression. Results: Although, at first glance, there was no macroscopic teratogen effect in forelimbs in all groups, via a stereological method, we showed that bone and cartilage volume decreased in the experimental group compared to the other groups. We also found that the experimental group had lower expression of the osteocalcin and RUNX2 gene than the control and sham groups did. However, there were no significant differences between the control and sham groups in terms of bone and cartilage volume and gene expression. Conclusion: Although teratogen effect of prenatal exposure to 2.4 GHz radio frequency on forelimbs was not demonstrated macroscopically, further studies showed negative effects on the forelimb bone, cartilage volume, and gene expression.

The Contribution of In Vivo Mammalian Studies to the Knowledge of Adverse Effects of Radiofrequency Radiation on Human Health

The proliferation of cellular antennas and other radiofrequency radiation (RFR) generating devices of the last decades has led to more and more concerns about the potential health effects from RFR exposure. Since the 2011 classification as a possible carcinogen by the International Agency for Research on Cancer (IARC), more experimental studies have been published that support a causal association between RFR exposure and health hazards. As regard cancer risk, two long-term experimental studies have been recently published by the US National Toxicology Program (NTP) and the Italian Ramazzini Institute (RI). Despite important experimental differences, both studies found statistically significant increases in the development of the same type of very rare glial malignant tumors. In addition to carcinogenicity, reproductive organs might be particularly exposed, as well as sensitive to RFR. In this work, we reviewed the currently available evidence from in vivo studies on carcinogenicity and reproductive toxicity studies in order to summarize the contribution of experimental research to the prevention of the adverse effects of RFR on human health.

A rare case of monozygotic iniodymic diprosopiasis in a German Holstein calf

Craniofacial duplication abnormity is a rare phenomenon in buiatric practice. This report attends to a male German Holstein calf which could be classified as a diprosopic iniodymus. A fetus exhibiting a doubled face was delivered after fetotomy. To our knowledge, this is the first description of diprosopiasis with two cranial cavities as well as two separate encephala in a calf showing the potential extent of duplication. Throughout this work also the question is answered of whether this malformation in a bovine species arose from one embryo or rather, there is a dizygotic background by genotyping of tissue samples from both parts of the diprosopus. Regarding etiology, not only hereditary dispositions including among others a failed function of the signaling molecule Sonic hedgehog mediating regulation of craniofacial morphogenesis, but also incompletely separated monozygotic twins are discussed.