Bioeffects of Low Energy Ion-Beam Implantation and Vacuum Treatment on M_1 Arabidopsis Thaliana

Vacuum treatment and ion-beam bombardment are two major processes in the low energy ion-beam implantation. To accurately study the contributions of these two major factors to the bioeffects separately, the M1 generation variation of Arabidopsis thaliana with ion-beam implantation and vacuum treatment were compared through a series of key plant development parameters including morphological observation, biochemical assay and RAPD （random amplified polymorphic DNA） analysis. The results showed that ion-beam implantation had obvious effect on almost all of these parameters, and the vacuum treatment had some impacts on several morphological parameters such as the bolting time and the length of the primary stem. Taking the results together, the indication is that vacuum treatment has some slight contributions to the bioeffects of ion-beam implantation while ion-beam bombardment itself is the major creator of the bioeffects.

Bioeffects of Microgravity and Hypergravity on Animals

Gravity alterations in space cause significant adaptive effects on the human body,including changes to the muscular,skeletal,and vestibular systems.However,multiple factors besides gravity exist in space;therefore,it is difficult to distinguish gravity-related bioeffects from those of the other factors,including radiation.Although everything on the Earth surface is subject to gravity,gravity-induced effects are not explicitly clear.Here,different research methods that have been used in gravity alterations,including parabolic flight,diamagnetic levitation,and centrifuge,are reviewed and compared.The bioeffects that are reported to be associated with altered gravity in animals are summarized,and the potential risks of hypergravity and microgravity are discussed,with a focus on microgravity,which has been studied more extensively.It should be noted that although various microgravity and hypergravity research methods have their limitations,such as the inevitable magnetic field effects in diamagnetic levitation and short duration of parabolic flight,it is evident that ground-based clinical,animal,and cellular experiments that simulate gravity alterations have served as important and necessary complements to space research.These researches not only provide critical and fundamental biological information on the effects of gravity from biomechanics and the biophysical perspectives,but also help in developing future countermeasures for astronauts.

Experimental study and mechanism analysis on bioeffects by nanosecond electromagnetic pulses

The athermal bioeffects caused by nanosecond electromagnetic pulses with body cells was studied by using a broad band transverse EM-wave cell (BTEM CELL). The experimental system and preliminary mechanism analysis were presented.

Investigation on the intelligence quotient of children in the areas with high REE background (Ⅰ)-- REE bioeffects in the REE-high areas of southern Jiangxi Province

In China,rare earth elements(REE)are widely utilized in agriculture.Many studieson REE toxicology,pharmacology and biochemistry have been made both at home andabroad.However,REE damage to the functions of human memory,thinking andreasoning in animal experiments cannot be directly demonstrated.

High intensity focused ultrasound in clinical tumor ablation

Recent advances in high intensity focused ultrasound(HIFU),which was developed in the 1940s as a viable thermal tissue ablation approach,have increased its popularity.In clinics,HIFU has been applied to treat a variety of solid malignant tumors in a well-defined volume,including the pancreas,liver,prostate,breast,uterine fibroids,and soft-tissue sarcomas.In comparison to conventional tumor/cancer treatment modalities,such as open surgery,radio-and chemo-therapy,HIFU has the advantages of non-invasion,non-ionization,and fewer complications after treatment.Over 100 000 cases have been treated throughout the world with great success.The fundamental principles of HIFU ablation are coagulative thermal necrosis due to the absorption of ultrasound energy during transmission in tissue and the induced cavitation damage.This paper reviews the clinical outcomes of HIFU ablation for applicable cancers,and then summarizes the recommendations for a satisfactory HIFU treatment according to clinical experience.In addition,the current challenges in HIFU for engineers and physicians are also included.More recent horizons have broadened the application of HIFU in tumor treatment,such as HIFU-mediated drug delivery,vessel occlusion,and soft tissue erosion(“histotripsy”).In summary,HIFU is likely to play a significant role in the future oncology practice.

Metabolic fate of tea polyphenols and their crosstalk with gut microbiota

Tea represents an abundant source of naturally occurring polyphenols.Tea polyphenols(TPs)have received growing attentions for its wide consumption in the world,and more importantly its pleiotropic bioeffects for human health.After ingestion,TPs may undergo absorption and phase II reaction in the small intestine,and most undigested proportion would be submitted to the colon to interact with gut microbiota.Interactions between gut microbiota and TPs are bidirectional,including not only bacteria-mediated TPs metabolism,e.g.,removal of gallic acid moiety and ring fission to release phenolic acid catabolites,but also TPs-based modification of bacterial profiles.Crosstalk between TPs and gut microbes may benefit for gut barrier function,for example,improvement of the intestinal permeability to alleviate inflammation.Moreover,by reshaping microbial composition and associated metabolites,TPs may exert a systemic protection on host metabolism,which contributes to improve certain chronic metabolic disorders.Given that,further understanding of the metabolic fate of TPs and interplay with gut microbiota as well as potential health-promoting effects are of great significance to development and application of tea and their polyphenolic components in the future as dietary supplements and/or functional ingredients in medical foods.

A Novel Approach of Low-frequency Ultrasonic Naked Plasmid Gene Delivery and Its Assessment

Objective To deliver the naked genes into cells through the bioeffects of cell membrane porous produced by low-frequency ultrasound (US) and to investigate the safety by determining the threshold of cell damage and membrane permeability. Methods The suspension of red cells from chickens, rabbits, rats, and S180 cells was exposed to calibrated US field with different parameters in still and flowing state. Laser scanning confocal microscopy, fluorescent microscopy, scanning electron microscopy, flow cytometry and spectrophotometry were used to examine cell morphology, membrane permeability, enzymes, free radicals, naked gene expression efficiency, threshold of cell damage and cell viability. Results The plasmid of green fluorescent protein (GFP) as a reporter gene was delivered into S180 cells under optimal conditions without cell damage and cytotoxicity. The transfection rate was (35.83±2.53)% (n=6) in viable cells, and the cell viability was (90.17±1.47)% (n=6). Also, malondialdehyde, hydroxyl free radical, alkaline phosphatase, and acid phosphatase showed a S-shaped growth model (r=0.98±0.01) in response to the permeability change and alteration of cell morphology. The constant E of energy accumulation in US delivery at 90% cell viability was an optimal control factor, and at 80% cell viability was the damage threshold. Conclusion US under optimal conditions is a versatile gene therapy tool. The intensity of GFP expression in US group has a higher fluorescent peak than that in AVV-GFP group and control group (P<0.001). The optimal gene uptakes, expression of gene and safety depend on E, which can be applied to control gene delivery efficiency in combination with other parameters. The results are helpful for development of a novel clinical naked gene therapeutic system and non-hyperthermia cancer therapeutic system.

A Mathematical Model for Pulsating Flow of Ionic Fluid under an Axial Electric Field： EMF Effect on Blood Flow

The present work introduces a mathematical model for ionic fluid that flows under the effect of both pulsating pressure and axial electromagnetic field. The fluid is treated as a Newtonian fluid applying Navier-Stokes equation. The fluid is considered as a neutral mixture of positive and negative ions. The effect of axial electric field is investigated to determine velocity profiles. Hydroelectric equation of the flow is deduced under dc and ac external electric field. Hence the effect of applied frequency （0-1 GHz） and amplitude （10-350 V/m） is illustrated. The ultimate goal is to approach the problem of EMF field interaction with blood flow. The applied pressure waveform is represented as such to simulate the systolic-diastolic behavior. Simulation was carried out using Maple software using blood plasma parameters; hence velocity profiles under various conditions are reported.

Magnetic iron oxide nanoparticles accelerate osteogenic differentiation of mesenchymal stem cells via modulation of long noncoding RNA INZEB2

Nanomaterials are increasingly used for biomedical applications; thus, it is important to understand their biological effects. Previous studies suggested that magnetic iron oxide nanoparticles （IONPs） have tissue-repairing effects. In the present study, we explored cellular effects of IONPs in mesenchymal stem cells （MSCs） and identified the underlying molecular mechanisms. The results showed that our as-prepared IONPs were structurally stable in MSCs and promoted osteogenic differentiation of MSCs as whole particles. Moreover, at the molecular level, we compared the gene expression of MSCs with or without IONP exposure and showed that IONPs upregulated long noncoding RNA INZEB2, which is indispensable for maintaining osteogenesis by MSCs. Furthermore, overexpression of INZEB2 downregulated ZEB2, a factor necessary to repress BMP/Smad- dependent osteogenic transcription. We also demonstrated that the essential role of INZEB2 in osteogenic differentiation was ZEB2-dependent. In summary, we elucidated the molecular basis of IONPs＇ effects on MSCs; these findings may serve as a meaningful theoretical foundation for applications of stem cells to regenerative medicine.