Combination effects of pulsed electric field and low temperature plasma on H22 mouse liver cancer cell / 中华肝胆外科杂志

Objective:To investigate the effect of pulsed electric field (PEF) combined with low temperature plasma (LTP) on mouse liver cancer cell.Methods:H22 mouse liver cancer cells were divided into liver cancer group, PEF treatment group, LTP treatment group, combined group A (first PEF treatment immediately after LTP treatment), combined group B (first LTP treatment immediately after PEF treatment), combined group C (same as combined group A, but 20 minutes interval) and combined group D (same as combined group B, but 20 minutes interval). Cell viability was detected by cell counting, apoptosis was detected by flow cytometry, intracellular reative oxygen species (ROS) was marked by fluorescence and counted. Twenty healthy female Kunming mouse aged 4-6 weeks without specific pathogens were subcutaneous injected with liver cancer cells, and then were randomly divided into model group, PBS control group, PEF experimental group, LTP experimental group and combined group (LTP+ PEF, no interval) ( n=4). Tumor relative volume and tumor inhibition rate were measured. Results:The survival rates were liver cancer cell group (98.3±0.9)%, PEF treatment group (66.8±4.4)%, LTP treatment group (62.1±3.9)%, combined group A (43.7±3.7)%, combined group B (31.0±1.4)%, combined group C (46.8±2.9)%, combined group D (39.0±2.3)%. Compared with liver cancer cell group, the cell survival rate of all treatment groups was decreased, and the cell survival rate of the four combined treatment group was lower than that of PEF treatment group and LTP treatment group, the differences were statistically significant (all P<0.05). The survival rate of combined B group was the lowest. The results of apoptosis detection were consistent with those of cell survival rate. Under fluorescence microscope, the ROS fluorescence of cells in the combined group B was significantly increased, and the ROS fluorescence of cells in the LTP treatment group was more than that in the PEF treatment group, and the percentage of ROS positive cells in the combined group B was higher than that in the LTP treatment group and the PEF treatment group, with statistical significance (all P<0.05). Tumor relative volume and tumor inhibition rate in the combined group were better than those in the PEF and LTP groups, and the differences were statistically significant (all P<0.05). Conclusion:LTP combined with PEF has a better killing effect on H22 cells than PEF or LTP treatment, which is expected to be a new tumor therapy.

Progress in the Treatment of Tachyarrhythmia by Pulsed Electric Field Ablation Catheter Ablation / 中国医疗器械杂志

Pulsed electric field(PEF) provides high-energy instantaneous pulse and release energy to myocardial cell membrane, resulting in irreversible electroporation and causes myocardial cell contents leakage, destruction of intracellular homeostasis, cell death, and slight inflammatory response. PEF as non-thermal energy promotes the design and application of arrhythmia ablation catheter to enter a new stage. There are currently limited clinical studies that have proved the safety and effectieness of Farawave PEF catheter, PVAC GOLD PEF catheter, Lattice-tip Sphere-9 PEF and radiofrequency (RF) catheter used for atrial fibrillation ablation, but still need further discussion. The research of atrial fibrillation ablation with PEF is under study in China. In this paper, the design and application of PEF ablation for tachyarrhythmia are reviewed.

A new technology for the treatment of atrial fibrillation: pulsed electric field ablation / 国际生物医学工程杂志

Atrial fibrillation, also known as atrial fibrillation, is a common cardiac arrhythmia, and its incidence increases with age. Catheter ablation is considered to be an effective means to treat atrial fibrillation and maintain sinus rhythm. The common ablation technologies are radiofrequency ablation and cryoablation. However, the existing catheter ablation technology has a "zero-sum effect", and it is difficult to control the optimal dose clinically. In this study, a new method of pulsed electric field ablation for atrial fibrillation was proposed, which effectively solved the "zero-sum effect" problem of temperature ablation. The clinical application results show that the proposed technology effectively overcomes the shortcomings of existing temperature ablation, and can form durable pulmonary vein isolation.

Lever positioning manipulation combined with pulsed electric field on the analgesic effect of patients with lumbar disc herniation and its influence on IL-1β and TNF-α / 中国骨伤

OBJECTIVE@#To observe the analgesic effect of lever positioning manipulation combined with pulsed electric field on patients with lumbar disc herniation and the influence on serum IL-1β and TNF-α.@*METHODS@#From January 2018 to March 2019, 58 patients with lumbar disc herniation were included in the study, which were randomly divided into observation group and control group by digital table method. Observation group of 29 cases, including 16 males and 13 females, aged (38.03±11.29) years old, were treated with lever positioning manipulation combined with pulsed electric field. The 29 cases in control group, including 17 males and 12 females, aged (38.21±9.16) years old, were treated with pulsed electric field. Both groups of patients were treated 3 times a week, once every other day, 3 times as a course of treatment. After 2 courses of treatment, the two groups of patients were scored before and after treatment by the numeric rating scales (NRS);at the same time, the serum levels of IL-1β and TNF-α were measured before and after treatment.@*RESULTS@#The NRS scores of observation group and control group were 4.21±1.76, 4.66±1.61 before treatment, and 1.28±0.84, 2.10±1.35 after treatment, respectively. The NRS scores of the observation group after treatment was significantly lower than that of the control group (@*CONCLUSION@#The lever positioning manipulation combined with pulsed electric field has a good analgesic effect on patients with lumbar disc herniation, and it has a significant impact on the patient's serum IL-1β and TNF-α concentration, which can be used as a clinical guide. However, the synergistic effect of lever positioning technique combined with pulsed electric field and guidelines for clinical treatment need further research.

Applications of new methods in extraction of flavonoids from Chinese materia medica / 中草药

Flavonoids are widely found in medicinal plants, which have important medical properties. Flavonoids were proved to have many pharmacological activities, such as anti-oxidation, antitumor, antimutation, anti-inflammatory, antibacterial and anti-aging. The extraction of flavonoids is the crucial link in their clinical applications. In recent years, many emerging Chinese medicine extraction methods have also been widely used in the extraction of flavonoids. This paper reviews the current application of new methods for flavonoid extraction, in order to provide references for the extraction, development and utilization of flavonoids. These new extraction methods include supercritical fluid extraction (SFE), ultrasonic assisted extraction (UAE), microwave assisted extraction (MAE), pressurized liquid extraction (PLE), pulsed electric field (PEF) assisted extraction, enzyme assisted extraction (EAE), green solvent extraction, steam explosion assisted extraction, dynamic high pressure microfluidization (DHPM) assisted extraction, etc.

Research Progress in the Effect of High-voltage Pulsed Electric Field on Microorganism Inactivation / 中国药师

Objective:To review the inactivation effect of high-voltage pulsed electric field on microorganism to provid theoretical basis for the further research and sterilization application of high-voltage pulsed electric field. Methods:The combination of high-volt-age pulse electric field, microbiology and pulse electric field as the keywords, the research results of high-voltage pulsed electric field on microbial inactivation in PubMed, CNKI, VIP Chinese journal full text database and Wanfang database during 2010 and 2015 were retrieved, summarized and reviewed. Results:As a non-thermal sterilization technology, high-voltage pulsed electric field not only had the characteristics of short sterilization time, narrow increasing extent of temperature and low energy consumption, but also could keep the original flavor of food. Conclusion:With the development of related technology, high-voltage pulsed electric field is expected to re-alize industrialization.

Optimization of extration process of protein and polysaccharides from Antler Velvet assisted by high intensity pulsed electric fields / 中国药学杂志

OBJECTIVE: To optimize the extraction proces of protein and polysaccharides from Antler Velvet using high intensity pulsed electric fields. METHODS: With water as solvent, electric field intensity, pulse number and solid-liquid ratio as investigation parameters, an L9(34) orthogonal test was used to determine the optimal process for simultaneous extraction of protein and polysaccharides from Antler Velvet. RESULTS: When the extraction by high intensity pulsed electric fields was conducted at the solid-liquid ratio of 1:30 g·mL-1 and electric field intensity of 20 kV·cm-1, with pulse number of 10, the protein extraction rate reached 12.32%, and polysaccharides extraction rate could reach 3.25%. CONCLUSION: The optimized process can effectively and simu-taneously extract protein and polysaccharides from Antler Velvet.

In vivo killing effects of nanosecond pulsed electric fields on mouse breast cancer / 国际生物医学工程杂志

Objective To explore the in vivo killing effects of nanosecond pulsed electric fields on mouse breast cancer in tumor bearing BALB/c mice. Methods Twenty four BALB/c mice models with subcutaneous EMT-6 breast cancer were prepared and divided into experimental group and control group (n=12). In experimental group, the mice were treated by the pulsed electric fields with peak voltage of 700 V/cm, rise times of 57 ns, durations of 70μs and duty ratio of 50%on the tumor tissue with two parallel electrodes under anaesthesia. One hundred pulses were given and the energy was just 9.75 J with effective action period of 7 ms. Tumor volume, animal weight and histopathologic changes after 1, 3, 5 and 7 d were observed after irreversible electroporation. Results The tumor volume in experimental group increased more slowly than that in control group, especially at the 1-3 d after treatment with a standstill. Histopathological examination results showed that the tumor tissue had obvious coagulation necrosis and tissue edema after electrical stimulation treatment, and mass vacuole like structure appeared in tumor tissue from the third day after treatment and vascular injury occurred at the early stage. Conclusions In the given field conditions, steep pulsed electric field has inhibitory effect on tumor growth. In order to achieve more ideal tumor therapy effect, further studies on steep pulse dose are needed.

Influence of picosecond pulse electric field to invasive ability of cervical cancer / 解放军医学杂志

Objective To investigate the influence of picosecond pulse electric field (psPEF) to the invasive ability of cervical cancer. Methods The model of cervical cancer was reproduced in BALB/c nude mice (n=24), and they were randomly divided into four groups (n=6) when the xenografts had grown reaching a diameter of 0.8-1.0cm: control group (psPEF was not given), low field intensity group (50kV/cm), moderate field intensity group (60kV/cm) and high field intensity group (70kV/cm). Seven days after the psPEF treatment, the histomorphological changes were observed with HE staining and transmission electron microscopy (TEM), the expressions of vascular endothelial growth factor (VEGF) and matrix metalloproteinases-9 (MMP-9) were determined with immunohistochemical (IHC) staining, and the changes in protein level of VEGF and MMP-9 were assessed with Western blotting. ResultsAfter psPEF treatment, the area of necrosis was found to be increased with an increase in psPEF intensity. With TEM different degrees of apoptosis and necrosis in tumor cells with an increase of psPEF intensity were found. IHC showed that the number of VEGF and MMP-9 positive cells in cancer tissue was decreased with an increase in psPEF intensity. The average optical density (AOD) of VEGF and MMP-9 proteins decreased significantly in psPEF treatment groups compared with that in control group, and the AOD values in psPEF treatment groups decreased with an increase in psPEF intensity, and the decrease was statistically significant (P<0.05). Western blotting showed the expressive levels of VEGF and MMP-9 proteins declined gradually with an increase in psPEF intensity, and the difference between groups was statistically significant (P<0.05). Conclusion psPEF may have anti-cervical cancer effects by inhibiting the secretion of VEGF and MMP-9 and reducing the invasive ability of cervical cancer cells.

Campo elétrico pulsado / Pulsed electric field

Campos elétricos pulsados de alta intensidade (CEPAI) constituem um método não-térmico de conservação para alimentos em substituição à pasteurização tradicional. Em comparação ao processamento térmico, os CEPAI, além de serem eficientes na eliminação de micro-organismos e na inativação de enzimas, também minimizam as perdas de sabor, cor, textura, nutrientes e componentes termolábeis dos alimentos. O objetivo desse trabalho foi levantar dados bibliográficos atuais sobre o tema CEPAI, abordando: definição do processo, instalação experimental, efeito da ruptura dielétrica do alimento, efeito sobre micro-organismo, enzimas e constituintes dos alimentos. Os dados encontrados na literatura apontam o tratamento por CEPAI como alternativa promissora para a conservação de alimentos, podendo ser utilizado como tecnologia única ou como complemento aos processamentos térmicos.

Pulsed electric fields of high intensity (HIPEF) is a non-thermal food conservation to replace traditional thermal pasteurization. Compared to thermal processing, the HIPEF as well as being effective in removing microorganisms and inactivate enzymes also minimize the loss of flavor, color, texture, nutrients and labile components of food. The aim of this work was to gather bibliographic data current HIPEF on the subject, covering: experimental setup, effects of dielectric breakdown of food, effect on microorganisms, enzymes and constituents of food. The data found in the literature indicate treatment of HIPEF as a promising alternative for food conservation and it could be used as a single technology or in addition to thermal processing.