Effects of static magnetic fields at the cellular level

Effects of Static and Low-Frequency Magnetic Fields on Gene Expression

Substantial research over the past two decades has established that magnetic fields affect fundamental cellular processes, including gene expression. However, since biological cells and subcellular components exhibit diamagnetic behavior and are therefore subjected to very small magnetic forces that cannot directly compete with the viscoelastic and bioelectric intracellular forces responsible for cellular machinery functions, it becomes challenging to understand cell-magnetic field interactions and to reveal the mechanisms through which these interactions differentially influence gene expression in cells. The limited understanding of the molecular mechanisms underlying biomagnetic effects has hindered progress in developing effective therapeutic applications of magnetic fields. This review examines the expanding body of literature on genetic events during static and low-frequency magnetic field exposure, focusing particularly on how changes in gene expression interact with cellular machinery. To address this, we conducted a systematic review utilizing extensive search strategies across multiple databases. We explore the intracellular mechanisms through which transcription functions may be modified by a magnetic field in contexts where other cellular signaling pathways are also activated by the field. This review summarizes key findings in the field, outlines the connections between magnetic fields and gene expression changes, identifies critical gaps in current knowledge, and proposes directions for future research. LEVEL OF EVIDENCE: NA TECHNICAL EFFICACY: Stage 4.

Effect of Moderate Static Magnetic Fields on Mice Oocyte Vitrification: Calcium-Related Genes Expression

The ability to cryopreserve oocytes without ultrastructural injury has been a concern in the development and use of methods to preserve female reproduction. The stability of the cell membrane must be preserved to reduce the damage caused by ice crystals during vitrification. One approach that has been explored is the use of static magnetic fields (SMFs), which are believed to influence cell membrane stability. In this study, the in vitro effects of SMF that range between 20-80 mT on the vitrification of mice germinal vesicle (GV) oocytes were studied. The viability and mitochondrial (Mt) membrane potential of both vitrified and nonvitrified oocytes were assessed using Trypan blue and JC1 staining. The high in vitro maturation (IVM) rate and high Mt membrane potential in metaphase II (MII) oocytes were taken into account to determine the optimal magnetic field intensity, that is, 20 mT. None of the SMF conditions resulted in intact spindles in MII oocytes. The study also explored the expression of store-operated calcium entry (Stim1, Orai1, and Ip3r) and meiosis resumption (Ccnb, Cdk) genes in GV and MII oocytes of both vitrified and control groups. The results show that the expressions of Orai1 and Ccnb genes in Vit-MII-SMF oocytes were considerably increased. However, no significant difference in Stim1 expression was observed between the groups. The Vit-MII-SMF group exhibited a significantly higher Ccnb expression compared to other groups. In vitro fertilization (IVF) was performed to evaluate the 2 pronuclear (2PN) rates. The findings demonstrated that using 20 mT SMF improved 2PN rates compared to the nonvitrified groups. This study provides a deeper understanding of the effects of moderate SMF and vitrification on the expression of calcium channel genes in GV and MII oocytes. The results suggest that applying a 20 mT SMF can help prevent cryoinjury and enhance the characteristics of vitrified-warmed oocytes.

The Influence of Physical Fields (Magnetic and Electric) and LASER Exposure on the Composition and Bioactivity of Cinnamon Bark, Patchouli, and Geranium Essential Oils

In recent years, essential oils (EOs) have received increased attention from the research community, and the EOs of cinnamon, patchouli, and geranium have become highly recognized for their antibacterial, antifungal, antiviral, and antioxidant effects. Due to these properties, they have become valuable and promising candidates for addressing the worldwide threat of antimicrobial resistance and other diseases. Simultaneously, studies have revealed promising new results regarding the effects of physical fields (magnetic and electric) and LASER (MEL) exposure on seed germination, plant growth, biomass accumulation, and the yield and composition of EOs. In this frame, the present study aims to investigate the influence of MEL treatments on cinnamon, patchouli, and geranium EOs, by specifically examining their composition, antimicrobial properties, and antioxidant activities. Results showed that the magnetic influence has improved the potency of patchouli EO against L. monocytogenes, S. enteritidis, and P. aeruginosa, while the antimicrobial activity of cinnamon EO against L. monocytogenes was enhanced by the electric and laser treatments. All exposures have increased the antifungal effect of geranium EO against C. albicans. The antioxidant activity was not modified by any of the treatments. These findings could potentially pave the way for a deeper understanding of the efficiency, the mechanisms of action, and the utilization of EOs, offering new insights for further exploration and application.

Application of magnetism in tissue regeneration: recent progress and future prospects

Tissue regeneration is a hot topic in the field of biomedical research in this century. Material composition, surface topology, light, ultrasonic, electric field and magnetic fields (MFs) all have important effects on the regeneration process. Among them, MFs can provide nearly non-invasive signal transmission within biological tissues, and magnetic materials can convert MFs into a series of signals related to biological processes, such as mechanical force, magnetic heat, drug release, etc. By adjusting the MFs and magnetic materials, desired cellular or molecular-level responses can be achieved to promote better tissue regeneration. This review summarizes the definition, classification and latest progress of MFs and magnetic materials in tissue engineering. It also explores the differences and potential applications of MFs in different tissue cells, aiming to connect the applications of magnetism in various subfields of tissue engineering and provide new insights for the use of magnetism in tissue regeneration.

Static magnetic field assisted thawing improves cryopreservation of mouse whole ovaries

Ovarian tissue cryopreservation is considered to be the only means to preserve fertility for prepubertal girls and women whose cancer treatment cannot be postponed. However, ovarian tissues are inevitably damaged by oxidative stress during cryopreservation, which threatens follicle survival and development, and thus affects female fertility. Therefore, reducing tissue oxidative stress injury is one of the major challenges to achieving efficient cryopreservation of ovarian tissues, especially for whole ovaries. Here, we proposed a new method to improve the antioxidant capacity of whole ovaries during cryopreservation, static magnetic field assisted thawing. The results demonstrated that the antioxidant capacity of the ovarian tissue was significantly improved by static magnetic field treatment. In addition, ovarian tissue allograft transplantation was carried out, which successfully achieved vascular regeneration and maintained follicular development. The findings of this study not only provide a new reference for the preservation of female fertility, but also is a major step forward in the cryopreservation of tissues and organs. It will have good application prospects in the field of assisted reproduction and cryo-biomedicine.

A concise review on wastewater treatment through microbial fuel cell: sustainable and holistic approach

Research for alternative sources for producing renewable energy is rising exponentially, and consequently, microbial fuel cells (MFCs) can be seen as a promising approach for sustainable energy production and wastewater purification. In recent years, MFC is widely utilized for wastewater treatment in which the removal efficiency of heavy metal ranges from 75-95%. They are considered as green and sustainable technology that contributes to environmental safety by reducing the demand for fossil fuels, diminishes carbon emissions, and reverses the trend of global warming. Moreover, significant reduction potential can be seen for other parameters such as total carbon oxygen demand (TCOD), soluble carbon oxygen demand (SCOD), total suspended solids (TSS), and total nitrogen (TN). Furthermore, certain problems like economic aspects, model and design of MFCs, type of electrode material, electrode cost, and concept of electro-microbiology limit the commercialization of MFC technology. As a result, MFC has never been accepted as an appreciable competitor in the area of treating wastewater or renewable energy. Therefore, more efforts are still required to develop a useful model for generating safe, clean, and CO2 emission-free renewable energy along with wastewater treatment. The purpose of this review is to provide a deep understanding of the working mechanism and design of MFC technology responsible for the removal of different pollutants from wastewater and generate power density. Existing studies related to the implementation of MFC technology in the wastewater treatment process along with the factors affecting its functioning and power outcomes have also been highlighted.

A Novel Magnetic Manipulation Promotes Directional Growth of Periodontal Ligament Stem Cells

Periodontium is the rally of soft and hard tissues, which will be devastated continuously by the compromise of periodontitis. Current periodontal therapeutic methods cannot effectively reconstruct periodontal ligament (PDL), which is oriented at an angle with tooth root and combined hard tissues to form cementum-PDL-alveolar bone complex. Hence, it is urgent to find new techniques for PDL reconstruction to achieve functional regeneration of periodontium. Herein, we developed a novel method to manipulate the distribution and growth of periodontal ligament stem cells (PDLSCs) by utilizing highly paralleled static magnetic field (SMF) and magnetic nanoparticles (MNPs). PDLSCs were incubated with MNPs in vitro to label with them. Meanwhile, CCK8 and live/dead cell staining assay were used to detect the impact of SMF and MNPs on cell viability. The directional migration and growth of PDLSCs were visualized under microscope. Furthermore, real-time quantitative PCR and western blot were utilized to calculate the expression level of PDL-related genes. The results showed that PDLSCs could rapidly take up MNPs without compromising cell proliferation and viability, consequently endowed with the ability to respond via magnetic force. The cell migration analysis indicated that PDLSCs could move along the magnetic induction line, testifying that SMF exerted forces on PDLSCs that labeled with MNPs. It was demonstrated that collective application of SMF and MNPs not only induced PDLSCs organized and grew directionally, but also initiated elongation of cells and nucleus. Furthermore, the morphological alteration of the nucleus could also effectively enhance the gene and protein expression of Collagen Ⅰα2, Collagen Ⅲ, and Periostin, suggesting the capability of PDLSCs to differentiate into PDL. In conclusion, this study exhibits a new approach for directional reconstruction of PDL to obtain physiological and functional regeneration of periodontium. The Clinical Trial Registration number: WCHSIRB-D-2022-458.

Antibacterial properties and osteoblast interactions of microfluidically synthesized chitosan - SPION composite nanoparticles

In this research, a multi-step microfluidic reactor was used to fabricate chitosan - superparamagnetic iron oxide composite nanoparticles (Ch - SPIONs), where composite formation using chitosan was aimed to provide antibacterial property and nanoparticle stability for magnetic resonance imaging (MRI). Monodispersed Ch - SPIONs had an average particle size of 8.8 ± 1.2 nm with a magnetization value of 32.0 emu/g. Ch - SPIONs could be used as an MRI contrast agent by shortening T2 relaxation parameter of the surrounding environment, as measured on a 3 T MRI scanner. In addition, Ch - SPIONs with concentrations less than 1 g/L promoted bone cell (osteoblast) viability up to 7 days of culture in vitro in the presence of 0.4 T external static magnetic field. These nanoparticles were also tested against Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa), which are dangerous pathogens that cause infection in tissues and biomedical devices. Upon interaction of Ch - SPIONs with S. aureus and P. aeruginosa at 0.01 g/L concentration, nearly a 2-fold reduction in the number of colonies was observed for both bacteria strains at 48 h of culture. Results cumulatively showed that Ch - SPIONs were potential candidates as a cytocompatible and antibacterial agent that can be targeted to biofilm and imaged using an MRI.

Mapping the Landscape of Magnetic Field Effects on Neural Regeneration and Repair: A Combined Systematic Review, Mathematical Model, and Meta-Analysis

Magnetic field exposure is a well-established diagnostic tool. However, its use as a therapeutic in regenerative medicine is relatively new. To better understand how magnetic fields affect neural repair in vitro, we started by performing a systematic review of publications that studied neural repair responses to magnetic fields. The 38 included articles were highly heterogeneous, representing 13 cell types, magnetic field magnitudes of 0.0002-10,000 mT with frequencies of 0-150 Hz, and exposure times ranging from one hour to several weeks. Mathematical modeling based on data from the included manuscripts revealed higher magnetic field magnitudes enhance neural progenitor cell (NPC) viability. Finally, for those regenerative processes not influenced by magnitude, frequency, or time, we integrated the data by meta-analyses. Results revealed that magnetic field exposure increases NPC proliferation while decreasing astrocytic differentiation. Collectively, our approach identified neural repair processes that may be most responsive to magnetic field exposure.

A review on the effect of nanocomposite scaffolds reinforced with magnetic nanoparticles in osteogenesis and healing of bone injuries

Many problems related to disorders and defects of bone tissue caused by aging, diseases, and injuries have been solved by the multidisciplinary research field of regenerative medicine and tissue engineering. Numerous sciences, especially nanotechnology, along with tissue engineering, have greatly contributed to the repair and regeneration of tissues. Various studies have shown that the presence of magnetic nanoparticles (MNPs) in the structure of composite scaffolds increases their healing effect on bone defects. In addition, the induction of osteogenic differentiation of mesenchymal stem cells (MSCs) in the presence of these nanoparticles has been investigated and confirmed by various studies. Therefore, in the present article, the types of MNPs, their special properties, and their application in the healing of damaged bone tissue have been reviewed. Also, the molecular effects of MNPs on cell behavior, especially in osteogenesis, have been discussed. Finally, the present article includes the potential applications of MNP-containing nanocomposite scaffolds in bone lesions and injuries. In summary, this review article highlights nanocomposite scaffolds containing MNPs as a solution for treating bone defects in tissue engineering and regenerative medicine.

Programing Cell Assembly via Ink-Free, Label-Free Magneto-Archimedes Based Strategy

Tissue engineering raised a high requirement to control cell distribution in defined materials and structures. In "ink"-based bioprintings, such as 3D printing and photolithography, cells were associated with inks for spatial orientation; the conditions suitable for one ink are hard to apply on other inks, which increases the obstacle in their universalization. The Magneto-Archimedes effect based (Mag-Arch) strategy can modulate cell locomotion directly without impelling inks. In a paramagnetic medium, cells were repelled from high magnetic strength zones due to their innate diamagnetism, which is independent of substrate properties. However, Mag-Arch has not been developed into a powerful bioprinting strategy as its precision, complexity, and throughput are limited by magnetic field distribution. By controlling the paramagnetic reagent concentration in the medium and the gaps between magnets, which decide the cell repelling scope of magnets, we created simultaneously more than a hundred micrometer scale identical assemblies into designed patterns (such as alphabets) with single/multiple cell types. Cell patterning models for cell migration and immune cell adhesion studies were conveniently created by Mag-Arch. As a proof of concept, we patterned a tumor/endothelial coculture model within a covered microfluidic channel to mimic epithelial-mesenchymal transition (EMT) under shear stress in a cancer pathological environment, which gave a potential solution to pattern multiple cell types in a confined space without any premodification. Overall, our Mag-Arch patterning presents an alternative strategy for the biofabrication and biohybrid assembly of cells with biomaterials featured in controlled distribution and organization, which can be broadly employed in tissue engineering, regenerative medicine, and cell biology research.

Static Magnetic Fields Promote Generation of Muscle Lineage Cells from Pluripotent Stem Cells and Myoblasts

Static magnetic fields (SMFs) exhibit numerous biological effects and regulate the proliferation and differentiation of several adult stem cells. However, the role of SMFs in the self-renewal maintenance and developmental potential of pluripotent embryonic stem cells (ESCs) remains largely uninvestigated. Here, we show that SMFs promote the expression of the core pluripotent markers Sox2 and SSEA-1. Furthermore, SMFs facilitate the differentiation of ESCs into cardiomyocytes and skeletal muscle cells. Consistently, transcriptome analysis reveals that muscle lineage differentiation and skeletal system specification of ESCs are remarkably strengthened by SMF stimuli. Additionally, when treated with SMFs, C2C12 myoblasts exhibit an increased proliferation rate, improved expression of skeletal muscle markers and elevated myogenic differentiation capacity compared with control cells. Together, our data show that SMFs effectively promote muscle cell generation from pluripotent stem cells and myoblasts. The noninvasive and convenient physical stimuli can be used to increase the production of muscle cells in regenerative medicine and the manufacture of cultured meat in cellular agriculture.

Compartmentalized agents: A powerful strategy for enhancing the detection sensitivity of chemical exchange saturation transfer contrast

Since the very beginnings of the chemical exchange saturation transfer (CEST) technique, poor overall sensitivity has appeared to be one of its strongest limitations for future applications. Research has therefore focused on designing systems, such as supramolecular and nanosized agents, that contain a high number of magnetically equivalent mobile spins. However, the number of mobile spins offered by these systems is still limited by their composition and surface/volume ratio. The design of compartmentalized agents, that is, systems where an aqueous inner core is separated from the MRI-detected bulk pool via a semipermeable barrier/membrane, is very much a step forward for the technique. These vesicular systems can (i) act as biocompatible and versatile carriers for dia-, para-, and hetero-nuclear CEST probes, thus offering new application options; and (ii) act as CEST probes themselves via the encapsulation of a suitable agent (e.g., a paramagnetic shift reagent) that can change the resonance frequency of the spin pool in the inner compartment only. LipoCEST agents were the pioneers in the latter category, as they are able to grant picomolar sensitivity (in terms of nanoparticle concentration), and paved the way for new applications for CEST agents, especially in the theranostic research area. The use of larger, natural vesicular systems, such as yeasts and cells, in which the huge number of intravesicular spins lowers the detection threshold to a femtomolar limit, is a further step forward in the development of compartmentalized CEST agents. Finally, interesting combinations of nanovesicular and cellular compartmentalized systems have been proposed, thus highlighting how the approach has the potential to drive CEST agents towards completing their journey to mature clinical translation.

The effect of magnetic fields on tumor occurrence and progression: Recent advances

Malignancies are the leading human health threat worldwide. Despite rapidly developing treatments, poor prognosis and outcome are still common. Magnetic fields have shown good anti-tumoral effects both in vitro and in vivo, and represent a potential non-invasive treatment; however, the specific underlying molecular mechanisms remain unclear. We here review recent studies on magnetic fields and their effect on tumors at three different levels: organismal, cellular, and molecular. At the organismal level, magnetic fields suppress tumor angiogenesis, microcirculation, and enhance the immune response. At the cellular level, magnetic fields affect tumor cell growth and biological functions by affecting cell morphology, cell membrane structure, cell cycle, and mitochondrial function. At the molecular level, magnetic fields suppress tumors by interfering with DNA synthesis, reactive oxygen species level, second messenger molecule delivery, and orientation of epidermal growth factor receptors. At present, scientific experimental evidence is still lacking; therefore, systematic studies on the biological mechanisms involved are urgently needed for the future application of magnetic fields to tumor treatment.

Effects of different physical factors on osteogenic differentiation

Osteoblasts are essential for bone formation and can perceive external mechanical stimuli, which are translated into biochemical responses that ultimately alter cell phenotypes and respond to environmental stimuli, described as mechanical transduction. These cells actively participate in osteogenesis and the formation and mineralisation of the extracellular bone matrix. This review summarises the basic physiological and biological mechanisms of five different physical stimuli, i.e. light, electricity, magnetism, force and sound, to induce osteogenesis; further, it summarises the effects of changing culture conditions on the morphology, structure and function of osteoblasts. These findings may provide a theoretical basis for further studies on bone physiology and pathology at the cytological level and will be useful in the clinical application of bone formation and bone regeneration technology.

Overview of Antimicrobial Biodegradable Polyester-Based Formulations

As the clinical complications induced by microbial infections are known to have life-threatening side effects, conventional anti-infective therapy is necessary, but not sufficient to overcome these issues. Some of their limitations are connected to drug-related inefficiency or resistance and pathogen-related adaptive modifications. Therefore, there is an urgent need for advanced antimicrobials and antimicrobial devices. A challenging, yet successful route has been the development of new biostatic or biocide agents and biomaterials by considering the indisputable advantages of biopolymers. Polymers are attractive materials due to their physical and chemical properties, such as compositional and structural versatility, tunable reactivity, solubility and degradability, and mechanical and chemical tunability, together with their intrinsic biocompatibility and bioactivity, thus enabling the fabrication of effective pharmacologically active antimicrobial formulations. Besides representing protective or potentiating carriers for conventional drugs, biopolymers possess an impressive ability for conjugation or functionalization. These aspects are key for avoiding malicious side effects or providing targeted and triggered drug delivery (specific and selective cellular targeting), and generally to define their pharmacological efficacy. Moreover, biopolymers can be processed in different forms (particles, fibers, films, membranes, or scaffolds), which prove excellent candidates for modern anti-infective applications. This review contains an overview of antimicrobial polyester-based formulations, centered around the effect of the dimensionality over the properties of the material and the effect of the production route or post-processing actions.

Semi-automated socio-anthropologic analysis of the medical discourse on rheumatoid arthritis: Potential impact on public health

BACKGROUND

The debilitating effects of noncommunicable diseases (NCDs) and the accompanying chronic inflammation represent a significant obstacle for the sustainability of our development, with efforts spreading worldwide to counteract the diffusion of NCDs, as per the United Nations Sustainable Development Goals (SDG 3). In fact, despite efforts of varied intensity in numerous directions (from innovations in biotechnology to lifestyle modifications), the incidence of NCDs remains pandemic. The present work wants to contribute to addressing this major concern, with a specific focus on the fragmentation of medical approaches, via an interdisciplinary analysis of the medical discourse, i.e. the heterogenous reporting that biomedical scientific literature uses to describe the anti-inflammatory therapeutic landscape in NCDs. The aim is to better capture the roots of this compartmentalization and the power relations existing among three segregated pharmacological, experimental and unstandardized biomedical approaches to ultimately empower collaboration beyond medical specialties and possibly tap into a more ample and effective reservoir of integrated therapeutic opportunities.

METHOD

Using rheumatoid arthritis (RA) as an exemplar disease, twenty-eight articles were manually translated into a nine-dimensional categorical variable of medical socio-anthropological relevance, relating in particular (but not only) to legitimacy, temporality and spatialization. This digitalized picture (9 x 28 table) of the medical discourse was further analyzed by simple automated learning approaches to identify differences and highlight commonalities among the biomedical categories.

RESULTS

Interpretation of these results provides original insights, including suggestions to: empower scientific communication between unstandardized approaches and basic biology; promote the repurposing of non-pharmacological therapies to enhance robustness of experimental approaches; and align the spatial representation of diseases and therapies in pharmacology to effectively embrace the systemic approach promoted by modern personalized and preventive medicines. We hope this original work can expand and foster interdisciplinarity among public health stakeholders, ultimately contributing to the achievement of SDG3.

Intermittent ELF-MF Induce an Amplitude-Window Effect on Umbilical Cord Blood Lymphocytes

In a previous study of the effects of intermittent extremely low frequency (ELF) magnetic fields (MF) on umbilical cord blood lymphocytes (UCBL), we evaluated MF amplitudes between 6 µT and 24 µT and found an effect only for those below 13 µT. This suggested the existence of an amplitude window. In this brief communication, we further tested this hypothesis. UCBLs from healthy newborns were isolated and exposed for 72 h to an intermittent ELF-MF (triangular, 7.8 Hz, 250 s ON/250 s OFF) with 6 different amplitudes between 3 µT and 12 µT, utilizing an oblong coil. Percentage of viable, early apoptotic (EA), and late apoptotic/necrotic (LAN) cells were determined by flow cytometry. Moreover, reactive oxygen species (ROS) were determined at 1 h and 3 h of the exposure. Like in our previous work, neither EA, nor LAN, nor ROS were statistically significantly affected by the intermittent ELF-MF. However, the percentage of viable cells was decreased by exposure to the fields with intensities of 6.5 µT and 12 µT (p < 0.05; and p = 0.057 for 8.5 µT). ELF-MF decreased the percentage of viable cells for fields down to 6.5 µT, but not for 5 µT, 4 µT, or 3 µT. Combined with our previous findings, the results reported here indicate an amplitude window effect between 6 µT and 13 µT. The obtained data are in line with a notion of amplitude and frequency windows, which request scanning of both amplitude and frequency while studying the ELF-MF effects.

Multidisciplinary and Nonpharmacological Management of Pain in Temporomandibular Disorders (TMDs)

Temporomandibular joint dysfunction (TMD) is not a single diagnosis, but a term covering a group of conditions that involve pain and dysfunction of the masticatory muscles within the temporomandibular joint (TMJ) and associated structures. It is a set of disease entities comprising various ailments and clinical symptoms. One of the most distressing symptoms for TMD patients is pain. Pain is subjective and always unpleasant. The VAS (visual analogue scale) was used in this research. The aim of this study was to assess the influence of physical stimuli, namely extremely low frequency magnetic field (ELF-MF) and LED light, on the experience of pain caused by increased tension in the masticatory muscles in adults. Out of 150 people examined, 104 were enrolled in the study after meeting the eligibility criteria. The study group was divided into 4 subgroups. Each subgroup received physical therapy treatment using a different physical stimulus. The effects of four therapeutic modalities were compared. In terms of VAS scores, pain attenuation was observed in all subgroups. The study confirmed the analgesic effect of the selected physical therapy methods. The authors focused on the analysis of the results obtained for each subgroup, comparing the effects of individual modalities on pain intensity (according to VAS scores). After the treatment, pain relief was observed in each of the studied subgroups. Treatment using ELF-MF and ELF-MF in combination with LED light in the course of TMD brings about a significant improvement in the subjective pain experience expressed in VAS pain scores. The use of selected physical stimuli and their beneficial effect on pain symptoms during mandibular movements has important implications for patients' daily life and work. Incorporation of therapeutic methods can help enhance patient satisfaction and comfort during manual TMJ therapy and lengthy dental procedures.

The impact of physical, biochemical, and electrical signaling on Schwann cell plasticity

Peripheral nervous system (PNS) injuries are an ongoing health care concern. While autografts and allografts are regarded as the current clinical standard for traumatic injury, there are inherent limitations that suggest alternative remedies should be considered for therapeutic purposes. In recent years, nerve guidance conduits (NGCs) have become increasingly popular as surgical repair devices, with a multitude of various natural and synthetic biomaterials offering potential to enhance the design of conduits or supplant existing technologies entirely. From a cellular perspective, it has become increasingly evident that Schwann cells (SCs), the primary glia of the PNS, are a predominant factor mediating nerve regeneration. Thus, the development of severe nerve trauma therapies requires a deep understanding of how SCs interact with their environment, and how SC microenvironmental cues may be engineered to enhance regeneration. Here we review the most recent advancements in biomaterials development and cell stimulation strategies, with a specific focus on how the microenvironment influences the behavior of SCs and can potentially lead to functional repair. We focus on microenvironmental cues that modulate SC morphology, proliferation, migration, and differentiation to alternative phenotypes. Promotion of regenerative phenotypic responses in SCs and other non-neuronal cells that can augment the regenerative capacity of multiple biomaterials is considered along with innovations and technologies for traumatic injury.

Biological Impact of γ-Fe2O3 Magnetic Nanoparticles Obtained by Laser Target Evaporation: Focus on Magnetic Biosensor Applications

The biological activity of γ-Fe2O3 magnetic nanoparticles (MNPs), obtained by the laser target evaporation technique, was studied, with a focus on their possible use in biosensor applications. The biological effect of the MNPs was investigated in vitro on the primary cultures of human dermal fibroblasts. The effects of the MNPs contained in culture medium or MNPs already uptaken by cells were evaluated for the cases of the fibroblast's proliferation and secretion of cytokines and collagen. For the tests related to the contribution of the constant magnetic field to the biological activity of MNPs, a magnetic system for the creation of the external magnetic field (having no commercial analogues) was designed, calibrated, and used. It was adapted to the size of standard 24-well cell culture plates. At low concentrations of MNPs, uptake by fibroblasts had stimulated their proliferation. Extracellular MNPs stimulated the release of pro-inflammatory cytokines (Interleukin-6 (IL-6) and Interleukin-8 (IL-8) or chemokine (C-X-C motif) ligand 8 (CXCL8)) in a concentration-dependent manner. However, the presence of MNPs did not increase the collagen secretion. The exposure to the uniform constant magnetic field (H ≈ 630 or 320 Oe), oriented in the plane of the well, did not cause considerable changes in fibroblasts proliferation and secretion, regardless of presence of MNPs. Statistically significant differences were detected only in the levels of IL-8/CXCL8 release.

Reliable reference genes for gene expression analyses under the hypomagnetic field in a migratory insect

Manipulating the hypomagnetic field (HMF), which is the absence or significant weakening (<5 μT) of the geomagnetic field (GMF), offers a unique tool to investigate magnetic field effects on organismal physiology, development, behavior and life history. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) has been utilized to study changes in gene expression associated with exposure to the HMF. However, selecting appropriate reference genes (RGs) with confirmed stable expression across environments for RT-qPCR is often underappreciated. Using three algorithms (BestKeeper, NormFinder, and GeNorm), we investigated the expression stability of eight candidate RGs when exposed to the HMF condition versus local GMF during developmental from juveniles to adults in the migratory insect pest, the brown planthopper Nilaparvata lugens. During the nymphal stage, RPL5 & α-TUB1, EF1-α & ARF1, RPL5 & AK, EF1-α & RPL5, and ARF1 & AK were suggested as the most stable RG sets in the 1st to 5th instars, respectively. For 1- to 3-day-old adults, AK & ARF1, AK & α-TUB1, AK & ARF1 and EF1-α & RPL5, AK & α-TUB1, AK & EF1-α were the optimal RG sets for macropterous and brachypterous females, respectively. ACT1 & RPL5, RPL5 & EF1-α, α-TUB1 & ACT1 and EF1-α & RPL5, ARF1 & ACT1, ACT1 & ARF1 were the optimal RG sets for macropterous and brachypterous males, respectively. These results will facilitate accurate gene expression analyses under the HMF in N. lugens. The verification approach illustrated in this study highlights the importance of identifying reliable RGs for future empirical studies of magnetobiology (including magnetoreception) that involve magnetic field intensity as a factor.

Effect of pine essential oil and rotating magnetic field on antimicrobial performance

This work presents the results ofa study which concerns the influence of rotating magnetic field (RMF) on the antibacterial performance of commercial pine essential oil. A suspension of essential oil in saline solution and Escherichia coli were exposed to the rotating magnetic Afield (the frequency of electrical current supplied by a RMF generator f = 1–50 Hz; the averaged values of magnetic induction in the cross-section of the RMF generator B = 13.13 to − 19.92 mT, time of exposure t = 160 min, temperature of incubation 37 °C). The chemical composition of pine (Pinus sylvestris L.) essential oil was determined by gas chromatography coupled with mass spectrometry (GC–MS). The main constituents were α-pinene (28.58%), β-pinene (17.79%), δ-3-carene (14.17%) and limonene (11.58%). The present study indicates the exposition to the RMF, as compared to the unexposed controls causing an increase in the efficacy of antibacterial properties of pine oil. We have shown that rotating magnetic fields (RMF) at a frequency, f, between 25 Hz to and 50 Hz increased the antimicrobial efficiency of oil a concentration lower than 50%.

Simultaneously enhanced treatment efficiency of simulated hypersaline azo dye wastewater and membrane antifouling by a novel static magnetic field membrane bioreactor (SMFMBR)

Operation performance and membrane fouling of a novel static magnetic field membrane bioreactor (SMFMBR) for treatment of hypersaline azo dye wastewater was investigated. The results showed that SMFMBRs possessed higher efficiency of dye decolorization, COD removal and detoxification than the control MBR without SMF. The (3#) SMFMBR equipped with 305.0 mT (the highest intensity) SMF displayed the best treatment performance among all the four reactors (named as 0#-3#, equipped with SMFs of 0 mT, 95.0 mT, 206.3 mT and 305.0 mT, respectively). Potentially effective microbes belonging to Rhodanobacter, Saccharibacteria genera incertae sedis, Defluviimonas, Cellulomonas, Cutaneotrichosporon, Candida and Pichia were enriched in three SMFMBRs, in both of suspended sludge and bio-cakes. The relative abundance of Candida and Pichia in suspended sludge of 3# SMFMBR was the highest among all the four reactors, suggesting their successful colonization and potentially persistent effect of bioaugmentation. On the other hand, SMF of higher intensity effectively mitigated membrane fouling. Less production of soluble microbial products (SMP) and extracellular polymeric substances (EPS), lower protein/polysaccharide (PN/PS) ratio in SMP and EPS, looser structure of bio-cakes on membrane surface, as well as lower relative abundance of potential fouling causing microbes (mainly bacteria) in microbial communities were determined in 3# SMFMBR than the other three groups.

Effect of an Extremely Low-Frequency Electromagnetic Field on the Concentration of Salivary Immunoglobulin A

Extremely Low-Frequency Electromagnetic Field (ELF MF) therapy is effective in the treatment of injury, inflammation and postoperative complications. Its clinical applications relate to bone unification, pain reduction, soft tissue oedema and the decrease of electric potentials in the oral cavity. It enhances regeneration of periapical bone lesions. It is obvious that cells (leukocytes, platelets, keratinocytes, osteoblasts) and proteins (fibrin, collagen, elastin and growth factors) exhibit alterations when exposed to an Extremely Low-Frequency Electromagnetic Field. The aim of the study was to evaluate the effect of an Extremely Low-Frequency Electromagnetic Field (ELF MF) on the parotid gland on the concentration of salivary immunoglobulin A. The study group consisted of 24 patients, aged 14–16, who underwent ELF MF on the parotid gland region. The control group comprised 25 matching persons. The IgA concentration in saliva samples was established using radial immunodiffusion. Following ELF MF, a statistically significant increase in the concentration of secretory immunoglobulin A was found in the study group, whereas in the control group, no statistically significant differences were noted. It can be concluded that an Extremely Low-Frequency Electromagnetic Field increases the activity of the immune system of the parotid gland.

A novel magnetically controlled bioreactor for ex vivo expansion of NK-92 cells

The application of natural killer (NK) cells as potential antitumor effector cells appears to be valuable for immunotherapies. However, the clinical use of NK cells is limited because the technical difficulties associated with mass production NK cells at sufficiently high numbers represents a great challenge. Ex vivo expansion of NK cells is a key technology for cell therapy. Bioreactor systems can generate homogeneous culture condition and modulate the environmental and biochemical cues. In this study, a novel magnetically controlled bioreactor was developed for supporting NK cells ex vivo expansion. Using synthetic magnetic beads, the stirring device of the magnetically controlled bioreactor generated reduced shearing force. The intermittent magnetic field was applied for magnetic beads movement to homogenize the culture system. NK-92 cells were cultured in the magnetically controlled bioreactor and the expansion and function of expanded cells were investigated on day 8. The results showed that the expansion of NK-92 cells in the bioreactor was 67.71 ± 10.60-fold, which was significantly higher than that of the T25 culture flask (P < 0.05). Moreover, the proportions of CD3-CD56+ cells and cell killing activity of expanded cells in the bioreactor did not reveal any differences compared to T25 flasks. Taken together, this study demonstrated the possibility of magnetically controlled bioreactor as a potent strategy in NK cells production for facilitating cancer immunotherapy.

Application of magnetic nanoparticles in cell therapy

Fe₃O₄ magnetic nanoparticles (MNPs) are biomedical materials that have been approved by the FDA. To date, MNPs have been developed rapidly in nanomedicine and are of great significance. Stem cells and secretory vesicles can be used for tissue regeneration and repair. In cell therapy, MNPs which interact with external magnetic field are introduced to achieve the purpose of cell directional enrichment, while MRI to monitor cell distribution and drug delivery. This paper reviews the size optimization, response in external magnetic field and biomedical application of MNPs in cell therapy and provides a comprehensive view.

Engineered Magnetic Nanocomposites to Modulate Cellular Function

Magnetic nanoparticles (MNPs) have various applications in biomedicine, including imaging, drug delivery and release, genetic modification, cell guidance, and patterning. By combining MNPs with polymers, magnetic nanocomposites (MNCs) with diverse morphologies (core-shell particles, matrix-dispersed particles, microspheres, etc.) can be generated. These MNCs retain the ability of MNPs to be controlled remotely using external magnetic fields. While the effects of these biomaterials on the cell biology are still poorly understood, such information can help the biophysical modulation of various cellular functions, including proliferation, adhesion, and differentiation. After recalling the basic properties of MNPs and polymers, and describing their coassembly into nanocomposites, this review focuses on how polymeric MNCs can be used in several ways to affect cell behavior. A special emphasis is given to 3D cell culture models and transplantable grafts, which are used for regenerative medicine, underlining the impact of MNCs in regulating stem cell differentiation and engineering living tissues. Recent advances in the use of MNCs for tissue regeneration are critically discussed, particularly with regard to their prospective involvement in human therapy and in the construction of advanced functional materials such as magnetically operated biomedical robots.

The Effect of Magnetic Field Gradient and Gadolinium-Based MRI Contrast Agent Dotarem on Mouse Macrophages

Magnetic resonance imaging (MRI) is widely used in diagnostic medicine. MRI uses the static magnetic field to polarize nuclei spins, fast-switching magnetic field gradients to generate temporal and spatial resolution, and radiofrequency (RF) electromagnetic waves to control the spin orientation. All these forms of magnetic static and electromagnetic RF fields interact with human tissue and cells. However, reports on the MRI technique's effects on the cells and human body are often inconsistent or contradictory. In both research and clinical MRI, recent progress in improving sensitivity and resolution is associated with the increased magnetic field strength of MRI magnets. Additionally, to improve the contrast of the images, the MRI technique often employs contrast agents, such as gadolinium-based Dotarem, with effects on cells and organs that are still disputable and not fully understood. Application of higher magnetic fields requires revisiting previously observed or potentially possible bio-effects. This article focuses on the influence of a static magnetic field gradient with and without a gadolinium-based MRI contrast agent (Dotarem) and the cellular and molecular effects of Dotarem on macrophages.

Fundamental understanding of microbial fuel cell technology: Recent development and challenges

The research on microbial fuel cells (MFCs) is rising tremendously but its commercialization is restricted by several microbiological, material, and economic constraints. Hence, a systematic assessment of the research articles published previously focusing on potential upcoming directions in this field is necessary. A detailed multi-perspective analysis of various techniques for enhancing the efficiency of MFC in terms of electric power production is presented in this paper. A brief discussion on the central aspects of different issues are preceded by an extensive analysis of the strategies that can be introduced to optimize power generation and reduce energy losses. Various applications of MFCs in a broad spectrum ranging from biomedical to underwater monitoring rather than electricity production and wastewater treatment are also presented followed by relevant possible case studies. Mathematical modeling is used to understand the concepts that cannot be understood experimentally. These methods relate electrode geometries to microbiological reactions occurring inside the MFC chamber, which explains the system's behavior and can be improved. Finally, directions for future research in the field of MFCs have been suggested. This article can be beneficial for engineers and researchers concerned about the challenges faced in the application of MFC.

The effect of static magnetic field on bone mineral content in aging rats

Introduction: Aging is defined as a consequence of progressive accumulation of metabolic waste, which results in development of various disorders in the structure and function of cells over a number of years. It is followed by loss of bone tissue, where bones become less firm. The cycle of bone remodeling with age becomes longer, and the degree of bone mineralization decreases. Static magnetic fields (SMF) are stable magnetic fields that can be natural or artificial. Their moderate intensity (1mT-1T) affects physiological processes, cells, genetic material, behavior and development. So far, numerous studies have shown different effects of static magnetic fields on cell cultures, experimental animals, and the human population. Aim: Aim of this study was to determine the effect of static magnetic field (SMF) on bone mineral content (BMC) values in aging rats. Material and methods: Male Wistar rats, 3 years old, were used in the experiment. A total of 18 animals were divided into two groups: exposed (experimental group) and unexposed (control group). Nine animals from the experimental group were exposed to 30mT intensity static magnetic field for 10 weeks, while nine control rats were not exposed to the static magnetic field. Bone mineral content was measured by DXA (Dual-Energy X-Ray Absorptiometry. Results: Based on the experiment, it was found that after the exposure to the static magnetic field, in the experimental group, there is a statistically significant increase in the value of BMC in the trunk region and ribs region. In all other regions of interest: head, legs, pelvic bone, spine, total BMC - there were no statistically significant changes in BMC values. Conclusion: In the conducted experiment, a higher increase in the value of BMC was found in animals exposed to the SMF, compared to animals that were not exposed to the static magnetic field.

Effects of High Magnetic Fields on the Diffusion of Biologically Active Molecules

The diffusion of biologically active molecules is a ubiquitous process, controlling many mechanisms and the characteristic time scales for pivotal processes in living cells. Here, we show how a high static magnetic field (MF) affects the diffusion of paramagnetic and diamagnetic species including oxygen, hemoglobin, and drugs. We derive and solve the equation describing diffusion of such biologically active molecules in the presence of an MF as well as reveal the underlying mechanism of the MF’s effect on diffusion. We found that a high MF accelerates diffusion of diamagnetic species while slowing the diffusion of paramagnetic molecules in cell cytoplasm. When applied to oxygen and hemoglobin diffusion in red blood cells, our results suggest that an MF may significantly alter the gas exchange in an erythrocyte and cause swelling. Our prediction that the diffusion rate and characteristic time can be controlled by an MF opens new avenues for experimental studies foreseeing numerous biomedical applications.

Biopharmaceutical-Type Chinese Hamster Ovary Cell Cultivation Under Static Magnetic Field Exposure: A Study of Genotoxic Effect

The lack of a sufficient research base is the reason for the ongoing discussion regarding the genotoxic effect of magnetic field (MF) exposure on mammalian cell cultures. Chinese hamster ovary (CHO) suspension-type cells, which are widely used for biopharmaceutical production, are potentially subjected to an increased MF when cultivated in bioreactors equipped with bottom-placed magnetically coupled stirring mechanisms. The main challenge for conducting research in this field remains the availability of a suitable experimental setup that generates an appropriate MF for the raised research question. In the present study, a simple and cost-effective experimental setup was developed that generated a static MF, similar to what has been modeled in large-scale bioreactors and, at the same time, was suitable for experimental cell cultivation in laboratory conditions. The measured maximum magnetic flux density to which the cells were exposed was 0.66 T. To assess the possible genotoxic effect, cells were continuously subcultivated in laboratory petri dishes for a period of 14 days, corresponding to a typical duration of a biopharmaceutical production process in a conventional fed-batch regime. The genotoxic effect was assessed using the cytokinesis-block micronucleus assay with fluorescent staining. Results showed that a 0.66-T static MF exposure had no significant long-term effect on cell viability and chromosomal damage but demonstrated a short-term effect on cell apoptosis. Significant increase in nuclear bud formation was observed. These findings may encourage other researchers in future studies investigating cellular responses to MF exposure and contribute relevant data for comparison.

The Review of Bioeffects of Static Magnetic Fields on the Oral Tissue-Derived Cells and Its Application in Regenerative Medicine

Magnets have been widely used in dentistry for orthodontic tooth movement and denture retention. Nevertheless, criticisms have arisen regarding the biosafety of static magnetic field (SMF) effects on surrounding tissues. Various controversial pieces of evidence have been discussed regarding SMFs on cellular biophysics, but little consensus has been reached, especially in the field of dentistry. Thus, the present paper will first review the safe use of SMFs in the oral cavity and as an additive therapy to orthodontic tooth movement and periodontium regeneration. Then, studies regarding SMF-incorporated implants are reviewed to investigate the advantageous effects of SMFs on osseointegration and the underlying mechanisms. Finally, a review of current developments in dentistry surrounding the combination of magnetic nanoparticles (MNPs) and SMFs is made to clarify potential future clinical applications.

Effect of magnetic field on the growth of the cultured Entamoeba histolytica isolated from patients in Palestine

Static magnetic field (SMF) is generated in vicinity of moving charge or current passing through conductor. In this study, we aimed to investigate the effect of SMF on the growth of the cultured Entamoeba histolytica (E. histolytica) trophozoites. Different SMF strengths with maximum value equals 30 mT (mT) was applied on the E.histolytica for different periods of times: 0 h, 24 h, 48 h, and 72 h. A modified diphasic liver infusion agar medium was used for culturing E. histolytica in vitro. The results showed the successful stabilization of culture of E. histolytica trophozoites. If we kept the sample for longer time, e. g. 14 days, the growth rate decreases to zero. When applying 10 mT and 15 mT SMF on the sample, it is found that the cultivated E. histolytica trophozoites dies after 4 and 2 days respectively. The experiments suggested that the SMF inhibited the growth and the propagation of E. histolytica cells. In addition, it completely killed all the cells in a short time interval which depend on the SMF strength. It is concluded that the SMFs inhibits the growth of E. histolytica and change the morphology of these cells. Thus, we recommend to use SMF as treatment to mitigate the growth of E. histolytica.

Static Magnetic Fields Effects on Polysaccharides Production by Different Microalgae Strains

Microalgae are able to produce many valuable biomolecules, such as polysaccharides, that presents a large diversity of biochemical structures and functions as antioxidant, antifungal, anticancer, among others. Static magnetic fields (SMF) influence the metabolism of microorganisms and has been shown as an alternative to increase microalgae biomass, yield and compounds production. Especially, some studies have highlighted that SMF application could enhance carbohydrate content. This study aimed to evaluate different conditions of SMF on Spirulina and Chlorella in indoor and outdoor conditions, in order to confirm the influence of SMF on polysaccharides production, evaluating which polysaccharidic fraction could be enhanced by SMF and highlighting a possible modification in EPS composition. Starch from Chlorella and exopolysaccharides (EPS) from Spirulina were quantified and characterized. SMF increased the starch content in Chorella fusca biomass. EPS productions from A. platensis and Spirulina sp. were not significantly increased, and global composition appeared similar to the controls (constituted basically of 80–86% neutral sugars and 13–19% uronic acids). However, the monosaccharide composition analysis revealed a significant modification of composition, i.e., the amount of fucose, arabinose, rhamnose, galactose and glucuronic acid was increased, while the glucose content was decreased. SMF application led to significant modification of polysaccharides production and this study demonstrate that combining the outdoor conditions with SMF, the starch content and EPS composition was positively affected.

The Effects of Static Magnetic Field on Orthodontic Tooth Movement in Mice

The application of static magnetic field (SMF) has been considered an effective and noninvasive method to accelerate orthodontic tooth movement. The objective of this study was to explore the effects of SMF on orthodontic tooth movement in mice. A total of 105 Balb/c mice (body mass: 25-30 g) were divided into experimental group (SMF + force, 48), control group (force only, 48), and blank group (neither SMF nor force, 9). After the placement of orthodontic appliances, the experimental group was exposed to the SMF environment generated by Neodymium-iron-boron (NdFeB) magnets with an intensity of 20-204 mT. At 1, 3, 7, 14, 21, and 28 days after appliance insertion, eight animals in both experimental and control groups were sacrificed and the left maxillae were dissected to measure the distance of tooth movement, respectively. Meanwhile, the width of periodontal ligament (PDL), length of hyalinized zone, and the number of osteoclasts were evaluated by hematoxylin-eosin and tartrate-resistant acid phosphatase staining. We finally found that the experimental group demonstrated an enhanced rate and greater cumulative amount of tooth movement than the control group (0.2887 ± 0.0041 mm vs. 0.2114 ± 0.0089 mm, P < 0.05). On Days 7, 14, and 28, the experimental group also displayed a significantly greater width of PDL. Earlier formation and removal of the hyalinized zone, and significantly more osteoclasts were observed in the experimental group as well. The results suggested that SMF may be a promising nonsurgical intervention to accelerate orthodontic tooth movement. © 2021 Bioelectromagnetics Society.

Magnetically stimulated azo dye biodegradation by a newly isolated osmo-tolerant Candida tropicalis A1 and transcriptomic responses

A recently isolated osmo-tolerant yeast Candida tropicalis A1, which could decolorize various azo dyes under high-salinity conditions, was systematically characterized in the present study. Stimulating dye-decolorization effectiveness and osmo-tolerance of the yeast by static magnetic field (SMF) was investigated and transcriptomic responses of the yeast to SMF was analyzed to propose possible mechanisms. The results demonstrated that the yeast A1 effectively decolorized (≥ 97.50% within 12 h) and detoxified (from high toxicity to low toxicity within 24 h) 70 mg/L Acid Red B (ARB) under the optimized conditions through a series of steps including naphthalene-amidine bond cleavage, reductive or oxidative deamination/desulfurization, open-loop of hydroxy-substituted naphthalene or benzene and TCA cycle. Moreover, dye decolorization performance and osmo-tolerance of the yeast A1 were further improved by 24.6 mT SMF. Genes encoding high-affinity hexose/glucose transporter proteins and NADH-ubiquinone oxidoreductase were up-regulated by 24.6 mT SMF, which might be responsible for the increase of dye decolorization. Significant up-regulation of glycerol-3-phosphate dehydrogenase and cell wall protein RHD3 suggested that osmo-tolerance was enhanced by 24.6 mT SMF through promoting production and intracellular accumulation of glycerol as compatible solute, as well as regulation of cell wall component. In conclusion, 24.6 mT SMF led to the up-regulation of related genes resulting in enhanced dye biodegradation efficiency and osmo-tolerance of the yeast A1.

The Effect of Static Magnetic Field on Methanogenesis in the Anaerobic Digestion of Municipal Sewage Sludge

The present study aimed to determine the effect of a 17.6 mT static magnetic field (SMF) on the efficiency of anaerobic digestion (AD) of municipal sewage sludge (MSS). The SMF had a significant impact on methane (CH4) production efficiency, the levels of fermentation rate (ηFMSS) vs. removal rate (ηVS), and the structure of the anaerobic bacteria consortium, but it did not affect cumulative biogas production. The highest CH4 yield (431 ± 22 dm3CH4/kgVS) and the highest methane content in the biogas (66.1% ± 1.9%) were found in the variant in which the SMF exposure time was 144 min/day. This variant also produced the highest ηFMSS and ηVS values, reaching 73.8% ± 2.3% and ηVS 36.9% ± 1.6%, respectively. Longer anaerobic sludge retention time in the SMF area significantly decreased AD efficiency and caused a significant reduction in the number of methanogens in the anaerobic bacteria community. The lowest values were observed for SMF exposure time of 432 min/day, which produced only 54.8 ± 1.9% CH4 in the biogas. A pronounced reduction was recorded in the Archaea (ARC915) and Methanosaeta (MX825) populations in the anaerobic sludge, i.e., to 20% ± 11% and 6% ± 2%, respectively.

Static magnetic field on behavior, hematological parameters and organ damage in spontaneously hypertensive rats

Previous studies showed contradictory results of static magnetic field (SMF) influence on behavior, hematological parameters and organ damage. The aim of this study was to investigate influence of subchronic continuous exposure to upward and downward oriented SMF of moderate intensity on behavior, hematological characteristics, heart and kidney tissue of spontaneously hypertensive rats. SH rats exposed to downward oriented SMF demonstrated lack of anxious-like behavior. SMF of either orientation caused decrease in the number of platelets in peripheral blood, granulocytes in the spleen and bone marrow and increase in the number of erythrocytes in the spleen, in both exposed groups. We also demonstrated that spontaneously hypertensive rats exposed to upward oriented SMF exhibited decreased lymphocytes count in blood, decreased bone marrow erythrocytes count and rats exposed to downward oriented SMF had increased lymphocytes count in bone marrow. The results showed adverse effect of differently oriented SMF on hematological parameters of spontaneously hypertensive rats. Also, exposure to different oriented SMF didn't affect their heart and kidney morphological characteristics.

Evaluation of frequency magnetic field, static field, and Temozolomide on viability, free radical production and gene expression (p53) in the human glioblastoma cell line (A172)

Thirteen million cancer deaths and 21.7 million new cancer cases are expected in the world by 2030. Glioblastoma is the most common primary malignant tumor of the central nervous system which is the most lethal type of primary brain tumor in adults with the survival time of 12-15 months after the initial diagnosis. Glioblastoma is the most common and most malignant type of brain tumor, and despite surgery, chemotherapy and radiation treatment, the average survival of patients is about 14 months. The current research showed that the frequency magnetic field (FMF) and static magnetic field (SMF) can influence cancer cell proliferation and coupled with anticancer drugs may provide a new strategy for cancer therapy. At the present study, we investigated the effects of FMF (10 Hz, 50 G), SMF (50 G) and Temozolomide (200 μm) on viability, free radical production, and p53 followed by p53 protein expression in the human glioblastoma cell line (A172) by MTT, NBT, RT-PCR and Western blot. Results showed that the effect of Temozolomide (TMZ) with SMF and FMF together increased the cytotoxicity, free radical production, and p53 followed by p53 protein expression in the human glioblastoma cell line (A172).

10.5 T MRI static field effects on human cognitive, vestibular, and physiological function

PURPOSE

To perform a pilot study to quantitatively assess cognitive, vestibular, and physiological function during and after exposure to a magnetic resonance imaging (MRI) system with a static field strength of 10.5 Tesla at multiple time scales.

METHODS

A total of 29 subjects were exposed to a 10.5 T MRI field and underwent vestibular, cognitive, and physiological testing before, during, and after exposure; for 26 subjects, testing and exposure were repeated within 2-4 weeks of the first visit. Subjects also reported sensory perceptions after each exposure. Comparisons were made between short and long term time points in the study with respect to the parameters measured in the study; short term comparison included pre-vs-isocenter and pre-vs-post (1-24 h), while long term compared pre-exposures 2-4 weeks apart.

RESULTS

Of the 79 comparisons, 73 parameters were unchanged or had small improvements after magnet exposure. The exceptions to this included lower scores on short term (i.e. same day) executive function testing, greater isocenter spontaneous eye movement during visit 1 (relative to pre-exposure), increased number of abnormalities on videonystagmography visit 2 versus visit 1 and a mix of small increases (short term visit 2) and decreases (short term visit 1) in blood pressure. In addition, more subjects reported metallic taste at 10.5 T in comparison to similar data obtained in previous studies at 7 T and 9.4 T.

CONCLUSION

Initial results of 10.5 T static field exposure indicate that 1) cognitive performance is not compromised at isocenter, 2) subjects experience increased eye movement at isocenter, and 3) subjects experience small changes in vital signs but no field-induced increase in blood pressure. While small but significant differences were found in some comparisons, none were identified as compromising subject safety. A modified testing protocol informed by these results was devised with the goal of permitting increased enrollment while providing continued monitoring to evaluate field effects.

Magnetically Actuated Manipulation and Its Applications for Cartilage Defects: Characteristics and Advanced Therapeutic Strategies

For the fact that articular cartilage is a highly organized and avascular tissue, cartilage defects are limited to spontaneously heal, which would subsequently progress to osteoarthritis. Many methods have been developed to enhance the ability for cartilage regeneration, among which magnetically actuated manipulation has attracted interests due to its biocompatibility and non-invasive manipulation. Magnetically actuated manipulation that can be achieved by introducing magnetic nanoparticles and magnetic field. This review summarizes the cutting-edge research on the chondrogenic enhancements via magnetically actuated manipulation, including cell labeling, cell targeting, cell assembly, magnetic seeding and tissue engineering strategies.

Improving Azo Dye Decolorization Performance and Halotolerance of Pichia occidentalis A2 by Static Magnetic Field and Possible Mechanisms Through Comparative Transcriptome Analysis

A halotolerant yeast, Pichia occidentalis A2, was recently isolated that can decolorize various azo dyes. The azo dye decolorization performance of this strain was characterized, including the degradation pathway and detoxification effects of this yeast. Additionally, the effect of static magnetic field (SMF) on this decolorization process was investigated. Activities of key enzymes were analyzed to estimate the change of metabolic activity. Furthermore, possible mechanisms were analyzed through detecting differentially expressed genes between yeast A2 in the absence and presence of SMF. The results indicated that yeast A2 displayed the optimal decolorization performance when the concentrations (in g/L) of glucose, (NH4)2SO4, yeast extract, and NaCl were 4.0, 1.0, 0.1, and ≤30.0, respectively. Meanwhile, the optimal rotation speed, temperature, and pH were 160 rpm, 30°C, and 5.0, respectively. Acid Red B was decolorized and detoxified by yeast A2 through successive steps, including cleavage of the naphthalene-amidine bond, reductive deamination, oxidative deamination/desulfurization, open-loop of hydroxy-substituted naphthalene, and tricarboxylic acid cycle. The dye decolorization efficiency and halotolerance of yeast A2 were enhanced by 206.3 mT SMF. The activities of manganese peroxidase, and laccase were elevated 1.37- and 1.16-fold by 206.3 mT SMF, but lignin peroxidase activity showed little change. It was suggested from the transcriptome sequence that the enhanced halotolerance might be related to the upregulated genes encoding the enzymes or functional proteins related to intracellular synthesis and accumulation of glycerol.

TENSCell: Imaging of Stretch-Activated Cells Reveals Divergent Nuclear Behavior and Tension

Mechanisms of cellular and nuclear mechanosensation are unclear, partially because of a lack of methods that can reveal dynamic processes. Here, we present a new concept for a low-cost, three-dimensionally printed device that enables high-magnification imaging of cells during stretch. We observed that nuclei of mouse embryonic skin fibroblasts underwent rapid (within minutes) and divergent responses, characterized by nuclear area expansion during 5% strain but nuclear area shrinkage during 20% strain. Only responses to low strain were dependent on calcium signaling, whereas actin inhibition abrogated all nuclear responses and increased nuclear strain transfer and DNA damage. Imaging of actin dynamics during stretch revealed similar divergent trends, with F-actin shifting away from (5% strain) or toward (20% strain) the nuclear periphery. Our findings emphasize the importance of simultaneous stimulation and data acquisition to capture mechanosensitive responses and suggest that mechanical confinement of nuclei through actin may be a protective mechanism during high mechanical stretch or loading.

Combination Design of Time-Dependent Magnetic Field and Magnetic Nanocomposites to Guide Cell Behavior

The concept of magnetic guidance is still challenging and has opened a wide range of perspectives in the field of tissue engineering. In this context, magnetic nanocomposites consisting of a poly(ε-caprolactone) (PCL) matrix and iron oxide (Fe₃O₄) nanoparticles were designed and manufactured for bone tissue engineering. The mechanical properties of PCL/Fe₃O₄ (80/20 w/w) nanocomposites were first assessed through small punch tests. The inclusion of Fe₃O₄ nanoparticles improved the punching properties as the values of peak load were higher than those obtained for the neat PCL without significantly affecting the work to failure. The effect of a time-dependent magnetic field on the adhesion, proliferation, and differentiation of human mesenchymal stem cells (hMSCs) was analyzed. The Alamar Blue assay, confocal laser scanning microscopy, and image analysis (i.e., shape factor) provided information on cell adhesion and viability over time, whereas the normalized alkaline phosphatase activity (ALP/DNA) demonstrated that the combination of a time-dependent field with magnetic nanocomposites (PCL/Fe₃O₄ Mag) influenced cell differentiation. Furthermore, in terms of extracellular signal-regulated kinase (ERK)1/2 phosphorylation, an insight into the role of the magnetic stimulation was reported, also demonstrating a strong effect due the combination of the magnetic field with PCL/Fe₃O₄ nanocomposites (PCL/Fe₃O₄ Mag).