Effects of high intensity non-ionizing terahertz radiation on human skin fibroblasts

Effect of terahertz radiation on cells and cellular structures

The paper presents the results of modern research on the effects of electromagnetic terahertz radiation in the frequency range 0.5-100 THz at different levels of power density and exposure time on the viability of normal and cancer cells. As an accompanying tool for monitoring the effect of radiation on biological cells and tissues, spectroscopic research methods in the terahertz frequency range are described, and attention is focused on the possibility of using the spectra of interstitial water as a marker of pathological processes. The problem of the safety of terahertz radiation for the human body from the point of view of its effect on the structures and systems of biological cells is also considered.

Adaptations of Escherichia coli K 12 to Synchrotron Sourced THz Radiation

The biological effects of electromagnetic field (EMF) irradiation in the terahertz (THz) range remain ambiguous, despite numerous studies that have been conducted. In this paper, the metabolic response of Escherichia coli K 12 to EMF irradiation was examined using a 1.0 W m-2 incident synchrotron source (SS) in the range of 0.5-18.0 THz for over 90 min of continuous exposure at 25 °C. This continuous SS THz exposure induced periodic decreases in the cell growth after 10, 20, and 40 min of exposure compared to a time-matched control; however, the number of viable cells thereafter grew. The physiological status of treated cells immediately after exposure was assessed by using the direct plate counting technique and electron microscopy. Analysis of scanning electron microscopy (SEM) and high-resolution cryogenic transmission electron (cryo-TEM) micrographs showed that approximately 20% of the SS THz-exposed E. coli cells exhibited a deformed outer membrane, membrane perturbations, and leakage of cytosol. The proteome changes in E. coli cells after 18 h postexposure were associated with cellular response to plasma membrane regulation including phospholipid biosynthetic process and osmotic stress. The results of this study highlighted that E. coli cells can promptly activate the fundamental mechanisms in response to prolonged exposure to THz radiation that are evolutionarily developed to withstand other environmental stressors.

Sub-Terahertz Imaging-Based Real-Time Non-Destructive Inspection System for Estimating Water Activity and Foreign Matter Depth in Seaweed

As the importance of hygiene and safety management in food manufacturing has been increasingly emphasized, research on non-destructive and non-contact inspection technologies has become more active. This study proposes a real-time and non-destructive food inspection system with sub-terahertz waves which penetrates non-conducting materials by using a frequency of 0.1 THz. The proposed system detects not only the presence of foreign matter, but also the degree of depth to which it is mixed in foods. In addition, the system estimates water activity levels, which serves as the basis for assessing the freshness of seaweed by analyzing the transmittance of signals within the sub-terahertz image. The system employs YOLOv8n, which is one of the newest lightweight object detection models. This lightweight model utilizes the feature pyramid network (FPN) to effectively detect objects of various sizes while maintaining a fast processing speed and high performance. In particular, to validate the performance in real manufacturing facilities, we implemented a hardware platform, which accurately inspects seaweed products while cooperating with a conveyor device moving at a speed of 45 cm/s. For the validation of the estimation performance against various water activities and the degree of depth of foreign matter, we gathered and annotated a total of 9659 sub-terahertz images and optimized the learning model. The final results show that the precision rate is 0.91, recall rate is 0.95, F1-score is 0.93, and mAP is 0.97, respectively. Overall, the proposed system demonstrates an excellent performance in the detection of foreign matter and in freshness estimation, and can be applied in several applications regarding food safety.

Unveiling the immune-modulating power of THz-FEL irradiation

As terahertz (THz) technology advances, the interaction between THz radiation and the living body, particularly its effects on the immune system, has attracted extensive attention but remains poorly understood. This study firstly elucidated that exposure to 3 THz-FEL radiation markedly suppressed contact hypersensitivity reactions in mice induced by DNFB, as evidenced by a reduction in ear thickness and a discernible recovery in the Th1/Th2 cell balance. 3 THz irradiation led to cellular stress in the irradiated skin locale, increasing the levels of IL-4 and IL-10 and modulating the activity and migration of dendritic cells and mast cells. Furthermore, THz irradiation precipitated a rapid alteration in the skin lipidome, altering several categories of bioactive lipids. These findings offer new insights into the immunomodulatory effects of THz radiation on living organisms and the potential underlying mechanisms, with implications for the development of therapeutic approaches in managing skin allergic diseases.

Non-Thermal Effects of Terahertz Radiation on Gene Expression: Systematic Review and Meta-Analysis

With the advancement of terahertz technology, unveiling the mysteries of terahertz has had a profound impact on the field of biomedicine. However, the lack of systematic comparisons for gene expression signatures may diminish the effectiveness and efficiency of identifying common mechanisms underlying terahertz effects across diverse research findings. We performed a comprehensive review and meta-analysis to compile patterns of gene expression profiles associated with THz radiation. Thorough bibliographic reviews were conducted, utilizing the PubMed, Embase, Web of Science, and ProQuest databases to extract references from published articles. Raw CEL files were obtained from Gene Expression Omnibus and preprocessed using Bioconductor packages. This systematic review (Registration No. CDR42024502937) resulted in a detailed analysis of 13 studies (14 papers). There are several possible mechanisms and pathways through which THz radiation could cause biological changes. While the established gene expression results are largely associated with immune response and inflammatory markers, other genes demonstrated transcriptional outcomes that may unravel unknown functions. The enrichment of genes primarily found networks associated with broader stress responses. Altogether, the findings showed that THz can induce a distinct transcriptomic profile that is not associated with a microthermal cellular response. However, it is impossible to pinpoint a single gene or family of genes that would accurately and reliably justify the patterns of gene expression response under THz exposure.

Can specific THz fields induce collective base-flipping in DNA? A stochastic averaging and resonant enhancement investigation based on a new mesoscopic model

We study the metastability, internal frequencies, activation mechanism, energy transfer, and the collective base-flipping in a mesoscopic DNA via resonance with specific electric fields. Our new mesoscopic DNA model takes into account not only the issues of helicity and the coupling of an electric field with the base dipole moments, but also includes environmental effects, such as fluid viscosity and thermal noise. Also, all the parameter values are chosen to best represent the typical values for the opening and closing dynamics of a DNA. Our study shows that while the mesoscopic DNA is metastable and robust to environmental effects, it is vulnerable to certain frequencies that could be targeted by specific THz fields for triggering its collective base-flipping dynamics and causing large amplitude separation of base pairs. Based on applying the Freidlin-Wentzell method of stochastic averaging and the newly developed theory of resonant enhancement to our mesoscopic DNA model, our semi-analytic estimates show that the required fields should be THz fields with frequencies around 0.28 THz and with amplitudes in the order of 450 kV/cm. These estimates compare well with the experimental data of Titova et al., which have demonstrated that they could affect the function of DNA in human skin tissues by THz pulses with frequencies around 0.5 THz and with a peak electric field at 220 kV/cm. Moreover, our estimates also conform to a number of other experimental results, which appeared in the last couple years.

Sensitivity of Neuroblastoma and Induced Neural Progenitor Cells to High-Intensity THz Radiation

THz radiation induces a variety of processes in cells and has attracted the attention of researchers in recent decades. Here, data on the effects of high-intensity terahertz (THz) radiation on human directly reprogrammed neural progenitor cells (drNPCs) and on neuroblastoma cells (SK-N-BE (2)) were obtained for the first time. The results demonstrated that the exposure of non-tumor and tumor cells to broadband (0.1-3 THz) THz pulses with the intensity of 21 GW/cm2 and the electric field strength of 2.8 MV/cm for 30 min induced neither a noticeable genotoxic effect nor a statistically significant change in the proliferative activity and cell differentiation. It was also shown that the combined effect of THz radiation and salinomycin, a promising antitumor agent, on neuroblastoma cells did not enhance the genotoxic effect of this antibiotic. However, further studies involving chemotherapy drugs and other exposure parameters are warranted to introduce this new concept into anti-tumor clinical practice and to enhance the efficacy of the existing approaches.

Terahertz-to-infrared converters for imaging the human skin cancer: challenges and feasibility

PURPOSE

Terahertz (THz) medical imaging is a promising noninvasive technique for monitoring the skin's conditions, early detection of the human skin cancer, and recovery from burns and wounds. It can be applied for visualization of the healing process directly through clinical dressings and restorative ointments, minimizing the frequency of dressing changes. The THz imaging technique is cost effective, as compared to the magnetic resonance method. Our aim was to develop an approach capable of providing better image resolution than the commercially available THz imaging cameras.

APPROACH

The terahertz-to-infrared (THz-to-IR) converters can visualize the human skin cancer by converting the latter's specific contrast patterns recognizable in THz radiation range into IR patterns, detectable by a standard IR imaging camera. At the core of suggested THz-to-IR converters are flat matrices transparent both in the THz range to be visualized and in the operating range of the IR camera, these matrices contain embedded metal nanoparticles (NPs), which, when irradiated with THz rays, convert the energy of THz photons into heat and become nanosources of IR radiation detectable by an IR camera.

RESULTS

The ways of creating the simplest converter, as well as a more complex converter with wider capabilities, are considered. The first converter is a gelatin matrix with gold 8.5-nm diameter NPs, and the second is a polystyrene matrix with 2-nm diameter NPs from copper-nickel MONEL® alloy 404.

CONCLUSIONS

An approach with a THz-to-IR converter equipped with an IR camera is promising in that it could provide a better image of oncological pathology than the commercially available THz imaging cameras do.

Studying the genotoxic effects of high intensity terahertz radiation on fibroblasts and CNS tumor cells

The data is obtained on the effect of high-intensity pulses of terahertz (THz) radiation with a broad spectrum (0.2-3 THz) on cell cultures. We have evaluated the threshold exposure parameters of THz radiation causing genotoxic effects in fibroblasts. Phosphorylation of histone H2AX at Ser 139 (γH2AX) was chosen as a marker for genotoxicity and a quantitative estimation of γH2AX foci number in fibroblasts was performed after cell irradiation with THz pulses for 30 min. No genotoxic effects of THz radiation were observed in fibroblasts unless peak intensity and electric field strength exceeded 21 GW cm-2 and 2.8 MV cm-1 , respectively. In tumor cell lines (neuroblastoma (SK-N-BE (2)) and glioblastoma (U87)), exposure to THz pulses with peak intensity of 21 GW cm-2 for 30 min caused no morphological changes as well as no statistically significant increase in histone phosphorylation foci number.

Control of actin polymerization via reactive oxygen species generation using light or radiation

Actin is one of the most prevalent proteins in cells, and its amino acid sequence is remarkably conserved from protozoa to humans. The polymerization-depolymerization cycle of actin immediately below the plasma membrane regulates cell function, motility, and morphology. It is known that actin and other actin-binding proteins are targets for reactive oxygen species (ROS), indicating that ROS affects cells through actin reorganization. Several researchers have attempted to control actin polymerization from outside the cell to mimic or inhibit actin reorganization. To modify the polymerization state of actin, ultraviolet, visible, and near-infrared light, ionizing radiation, and chromophore-assisted light inactivation have all been reported to induce ROS. Additionally, a combination of the fluorescent protein KillerRed and the luminescent protein luciferase can generate ROS on actin fibers and promote actin polymerization. These techniques are very useful tools for analyzing the relationship between ROS and cell function, movement, and morphology, and are also expected to be used in therapeutics. In this mini review, we offer an overview of the advancements in this field, with a particular focus on how to control intracellular actin polymerization using such optical approaches, and discuss future challenges.

Novel epigenetic therapeutic strategies and targets in cancer

The critical role of dysregulated epigenetic pathways in cancer genesis, development, and therapy has typically been established as a result of scientific and technical innovations in next generation sequencing. RNA interference, histone modification, DNA methylation and chromatin remodelling are epigenetic processes that control gene expression without causing mutations in the DNA. Although epigenetic abnormalities are thought to be a symptom of cell tumorigenesis and malignant events that impact tumor growth and drug resistance, physicians believe that related processes might be a key therapeutic target for cancer treatment and prevention due to the reversible nature of these processes. A plethora of novel strategies for addressing epigenetics in cancer therapy for immuno-oncological complications are currently available - ranging from basic treatment to epigenetic editing. - and they will be the subject of this comprehensive review. In this review, we cover most of the advancements made in the field of targeting epigenetics with special emphasis on microbiology, plasma science, biophysics, pharmacology, molecular biology, phytochemistry, and nanoscience.

Inhibition of Cancer Cell Migration and Glycolysis by Terahertz Wave Modulation via Altered Chromatin Accessibility

Metastasis and metabolic disorders contribute to most cancer deaths and are potential drug targets in cancer treatment. However, corresponding drugs inevitably induce myeloid suppression and gastrointestinal toxicity. Here, we report a nonpharmaceutical and noninvasive electromagnetic intervention technique that exhibited long-term inhibition of cancer cells. Firstly, we revealed that optical radiation at the specific wavelength of 3.6  μm (i.e., 83 THz) significantly increased binding affinity between DNA and histone via molecular dynamics simulations, providing a theoretical possibility for THz modulation- (THM-) based cancer cell intervention. Subsequent cell functional assays demonstrated that low-power 3.6  μm THz wave could successfully inhibit cancer cell migration by 50% and reduce glycolysis by 60%. Then, mRNA sequencing and assays for transposase-accessible chromatin using sequencing (ATAC-seq) indicated that low-power THM at 3.6  μm suppressed the genes associated with glycolysis and migration by reducing the chromatin accessibility of certain gene loci. Furthermore, THM at 3.6  μm on HCT-116 cancer cells reduced the liver metastasis by 60% in a metastatic xenograft mouse model by splenic injection, successfully validated the inhibition of cancer cell migration by THM in vivo. Together, this work provides a new paradigm for electromagnetic irradiation-induced epigenetic changes and represents a theoretical basis for possible innovative therapeutic applications of THM as the future of cancer treatments.

Selection criteria of image reconstruction algorithms for terahertz short-range imaging applications

Terahertz (THz) imaging has been regarded as cutting-edge technology in a wide range of applications due to its ability to penetrate through opaque materials, non-invasive nature, and its increased bandwidth capacity. Recently, THz imaging has been extensively researched in security, driver assistance technology, non-destructive testing, and medical applications. The objective of this review is to summarize the selection criteria for current state-of-the-art THz image reconstruction algorithms developed for short-range imaging applications over the last two decades. Moreover, we summarize the selected algorithms' performance and their implementation process. This study provides an in-depth understanding of the fundamentals of image reconstruction algorithms related to THz short-range imaging and future aspects of algorithm processing and selection.

From 5G to 6G—Challenges, Technologies, and Applications

As the deployment of 5G mobile radio networks gains momentum across the globe, the wireless research community is already planning the successor of 5G. In this paper, we highlight the shortcomings of 5G in meeting the needs of more data-intensive, low-latency, and ultra-high-reliability applications. We then discuss the salient characteristics of the 6G network following a hierarchical approach including the social, economic, and technological aspects. We also discuss some of the key technologies expected to support the move towards 6G. Finally, we quantify and summarize the research work related to beyond 5G and 6G networks through an extensive search of publications and research groups and present a possible timeline for 6G activities.

A Comparative Study on the Viability of Normal and Cancerous Cells upon Irradiation with a Steady Beam of THz Rays

Terahertz (THz) electromagnetic radiation is commonly used in astronomy, security screening, imaging, and biomedicine, among other applications. Such approach has raised the question of the influence of THz irradiation on biological objects, especially the human body. However, the results obtained to date are quite controversial. Therefore, we performed a comparative study on the viability of normal cells and cancer cells upon irradiation with a steady beam of THz rays. We used human peripheral blood mononuclear cells and cancer cell lines. Primary human mononuclear blood cells (monocytes, and B-, and T-cells) showed an increased death rate, determined by cell counting and fluorescence microscopy, upon 0.14 THz irradiation. The effect of THz radiation was different among malignant cells of B- and T-cell origin (Ramos and Jurkat cells) and epithelial cancer cells (MCF7 and LNCaP). This was demonstrated by cell counting and by the alamarBlue assay. In conclusion, THz radiation can result in the death of human primary and malignant cells. However, the mechanism of this phenomenon is largely unknown. Hence, more work should be done to shed some light on the mechanism of action of THz irradiation in living organisms to enhance technologic developments.

"Radio-Protective Effect of Aminocaproic Acid in Human Spermatozoa"

BACKGROUND

The negative effects of ionizing radiation on organs and the reproductive system are well known and documented. Exposure to gamma radiation can lead to oligospermia, azoospermia and DNA damage. Up to date, there is no effective pharmaceutical compound for protecting the male reproductive system and sperm.

OBJECTIVE

This study aimed at investigating the ability of Ɛ-aminocaproic acid (EACA) to prevent the damage of human spermatozoa and DNA induced by ionizing radiation.

MATERIALS AND METHODS

Sperm samples were obtained from healthy volunteers (35 men; 31.50 ± 7.34 years old). There were 4 experimental groups: 1) control group (CG), 2) group exposed to maximal radiation dose 67.88 mGy (RMAX), 3) low-dose radiation (minimal) 22.62 mGy (RMIN), and 4) group treated with radiation (67.88 mGy) and EACA (dose 50 ng/ml). Sperm motility, viability, and DNA damage were assessed.

RESULTS

We observed a significant decrease in total sperm motility of the RMAX group compared to CG (p < 0.05). Sperm viability in the RMAX group was also reduced in comparison to the control (p < 0.05). A significant increase in DNA fragmentation was detected in the RMAX group. The results demonstrated that the treatment of sperm with EACA led to a decrease in the fragmentation of the sperm DNA (compared to the RMAX group) (p < 0.05).

CONCLUSION

The results indicate that EACA effectively protects human spermatozoa from DNA damage induced by ionizing radiation. Treatment of spermatozoa with EACA led to the preservation of cell motility, viability, and DNA integrity upon radiation exposure.