1.Control of High Voltage Pulse Generator Based on Arduino and Its Peripheral Sensors for Cell Irreversible Electroporation Test.
Chinese Journal of Medical Instrumentation 2021;45(4):380-383
A project of control of a high voltage pulse generator based on Arduino and its peripheral pulse sensor and temperature sensor was proposed for cell irreversible electroporation (IRE) test. By programming Arduino board, the analog photoelectric signal and the partial voltage signal of thermistor collected by pulse and temperature sensors were converted into digital signal and temperature value. The threshold of ECG R wave (>550) and temperature threshold (<37 oC) was set as trigger condition to control an 800 W high voltage pulse generator to release a fixed period pulse. Human lung cancer cells cultured in vitro were used to test and verify, and cell staining was used to evaluate the perforation. The results showed that Arduino and its sensors were sensitive to trigger and feedback. When the high voltage pulse generator was controlled to release 100 pulses with the parameters of 600 V, 1 200 V/cm and 100 ms pulse width, more than 95% of the cells showed nonthermal irreversible electroporation.
Electroporation
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Humans
2.The effect of electroporation on the growth characteristics and antimicrobial activity of lactic acid bacteria
Howe-Nguong Wong ; Chee-Sian Kuan ; Chee-Hao Kuan ; Siok-Koon Yeo
Malaysian Journal of Microbiology 2021;17(5):514-524
Aims:
This study aimed to evaluate the effect of electroporation on the growth characteristics and antimicrobial activity of lactic acid bacteria (LAB) including Bifidobacterium longum ATCC 15707, Lactobacillus acidophilus ATCC 314, Lactobacillus casei ATCC 393 and Lactobacillus fermentum ATCC 14931.
Methodology and results:
Electroporation with the strength of electric field at 1.0–3.0 kV/cm for 2-4 millisecond were applied on the bacterial cultures. All bacterial cultures showed significant (P<0.05) increased in cell viability (40%-325%) upon electroporation. Such treatment also increased the acidity of the cell where the pH of cells decreased upon treatment. In tandem with the increased viability, electroporated bacterial cultures also showed higher proteolytic activity compared to the control (P<0.05). The electroporation treatment also increased (P<0.05) the bacteriocin activity of treated cells compared to the control. However, the molecular weight of bacteriocins produced were not affected by electroporation. Treated cells also possessed better antimicrobial activity. According to the results collected, all treated LAB strains showed 11.5%-113.8% higher (P<0.05) inhibitory activity compared to untreated control against tested pathogenic bacteria, Escherichia coli and Listeria monocytogenes that commonly associated with food contamination. Microarray data analysis showed that electroporation regulated the entities encoding for surface protein and transporter.
Conclusion, significance and impact of study
The results from this study suggested that electroporation could enhance the growth characteristics and antimicrobial activity of LAB by modifying the surface regions of the cells. This result may serve as the reference for food manufacturers to opt for effective biopreservation method and produce food with extended shelf life.
Electroporation
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Lactobacillales
3.Clinical burn injuries due to electroporation: mechanism still debate
Journal of Practical Medicine 1998;357(11):29-32
Joule heating has long been considered as the principal component of tissue damage in electrical injury. Recent studies suggest electroporation, a nonthermally medicated mechanism of cell membrane damage, is also an important factor. This study is significant because it directly addresses whether nonthermal mechanisms of cell damage can cause tissue necrosis without visible thermal changes.
Burns
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Wounds and Injuries
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Electroporation
4.Development of highly efficient electrocompetent cells for electroporation of Geobacillus thermoglucosidasius NCIMB 11955.
Ruihong BU ; Zhiheng YANG ; Zilong LI ; Guojian ZHANG ; Weishan WANG
Chinese Journal of Biotechnology 2023;39(8):3508-3519
Geobacillus thermoglucosidasius is a kind of Gram-positive facultative anaerobic bacteria. The fast growth rate under high temperature and less susceptibility to microbial contamination enable G. thermoglucosidasius to be a desirable producer of biofuels and high-value-added chemicals for the next-generation industrial biotechnology. However, compared with the classical model strain Escherichia coli, the applications of G. thermoglucosidasius are hampered by its low transformation efficiency. This study aimed at obtaining competent cells with high transformation efficiency through inactivating restriction enzymes, adding cell membrane inhibitors and cell wall weakening agents. The results showed that the electro-transformation efficiency achieved 1.2×104 CFU/(μg DNA) by knocking out four genes encoding restriction enzymes. Adding a certain amount of tween 80, dl-threonine and glycine further increased the competent efficiency about 22.5, 44, and 334 times, respectively. The electro-transformation efficiency was enhanced to 4.6×106 CFU/(μg DNA) under the optimized conditions, laying a foundation for genetic manipulation and metabolic engineering of G. thermoglucosidasius.
Electroporation
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Electroporation Therapies
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Bacillaceae
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Cell Membrane
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Escherichia coli/genetics*
5.Development Status of Irreversible Electric Perforated Tumor Ablation Device.
Tianshuai HE ; Kun TAN ; Qianqian SUN ; Zhirui ZHANG ; Xue CHEN ; Yi LYU ; Rongqian WU
Chinese Journal of Medical Instrumentation 2021;45(6):655-661
This study firstly introduced the mechanism, benefits and applications of irreversible electroporation(IRE) for tumor ablation. In addition, this study also introduced the most advanced IRE systems cleared by FDA or CFDA and IRE research equipment. The clinically licensed IRE systems include the Nanoknife 3.0 of Angiodynamics, the Dophi
Electricity
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Electroporation
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Heart Rate
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Humans
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Neoplasms/therapy*
6.Irreversible Electroporation in Patients with Pancreatic Cancer :Angel and Devil
Jiyoung KEUM ; Hee Seung LEE ; Huapyong KANG ; Jung Hyun JO ; Moon Jae CHUNG ; Jeong Youp PARK ; Seung Woo PARK ; Si Young SONG ; Seungmin BANG
Journal of Digestive Cancer Report 2019;7(1):26-30
Pancreatic cancer has a very poor prognosis. Complete surgical resection remains the only current curative treatment. Locally advanced pancreatic cancer (LAPC) is considered as unresectable because of involvement of celiac and/or mesenteric vessels. The treatment of LAPC is a challenge. Current guidelines suggest systemic therapy. However, the majority of patients will never experience conversion to surgical resection. Thus, in these patients, ablation is an alternative therapy for local control, which causes local destruction while ideally avoiding injury to surrounding healthy tissue. Irreversible electroporation (IRE) is an energy delivery system, effective in ablating tumors by inducing irreversible membrane destruction of cells. IRE demonstrated to be safe in previous studies. However, it is not free from complications, even serious. Here, we reported two cases of the IRE in LAPC patients.
Electroporation
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Humans
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Membranes
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Pancreatic Neoplasms
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Prognosis
7.Research Progress of Catheter-based Irreversible Electroporation for Tissue Ablation.
Yikun ZHOU ; Xuan HAN ; Fenggang REN ; Qingshan LI ; Xue CHEN ; Dake CHU ; Rongqian WU ; Yi LYU
Chinese Journal of Medical Instrumentation 2020;44(2):172-178
Irreversible electroporation (IRE) is an emerging tissue ablation technique. Compared with thermal ablation technique such as radiofrequency, IRE can achieve focal ablation in a shorter time without heat sink effect while sparing the tissue scaffold. IRE has been demonstrated to be a feasible therapeutic modality for the liver, pancreatic, and prostatic cancer. In recent years, several studies regarding of catheter-directed IRE for digestive tract, bronchus, urinary tract, and myocardium have been performed, which preliminarily demonstrated the safety and efficacy of IRE for tissue ablation under endoscopic or interventional technique. This study summarized the research progress of catheter-directed IRE for tissue ablation. The critical technique and future direction of catheter-based IRE are prosp.
Catheter Ablation
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Catheters
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Electroporation
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Endoscopy
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Humans
8.Analytical model for the transmembrane voltage induced on a permeabilized cell membrane in suspensions exposed to DC pulse fields.
Yurong QIN ; Yuehua JIANG ; Shengli LAI
Journal of Biomedical Engineering 2007;24(1):1-4
During the electroporation cell membrane conductivity increases dramatically, so the analytical model for calculating the transmembrane voltage (TMV) induced on an unpermeabilized cell membrane in suspensions can not be used in this case. An analytical model for the TMV induced on a permeabilized cell membrane in suspensions exposed to a high voltage DC pulse field was built. First, a permeabilized cell was replaced by a sphere cell having the equivalent conductivity. Then the average field inside the permeabilized cell suspensions was calculated according to the effective medium theory. Finally, based on the analytical solution for the TMV on a single unpermeabilized cell, an analytical model for the TMV on a permeabilized cell in suspensions was derived. The model shows that the TMV depends on parameters such as the external electric field, critical angle of electroporation, cell radium, conductivity of the cytoplasm, membrane and external medium, cell arrangement and cell volume fraction.
Cell Membrane Permeability
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Electric Conductivity
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Electromagnetic Fields
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Electrophysiology
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Electroporation
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Humans
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Membrane Potentials
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Models, Biological
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Pulse
9.Mechanism of DNA transformation based on mineral nanofibers and method improvement.
Haidong TAN ; Lei WANG ; Jintao LIN ; Zongbao ZHAO
Chinese Journal of Biotechnology 2010;26(10):1379-1384
Sepiolite--an inexpensive, resourceful, fibrous yet inoffensive mineral--made DNA transformation rapid, simple and efficient but the mechanism for DNA transformation was still unclear. Through RNA competition test, we proposed the different transforming mechanisms from the previous report. Meanwhile, we optimized the transforming method and could transfer a colony stored at 4 degrees C for a month with plasmid through sepiolite fibers. The cells could be transformed well without competent cells preparation or incubation process. In sum, this was a novel potential transforming method, which could be explored further if the chemical method and electroporation could not be used.
DNA, Bacterial
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chemistry
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genetics
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Electroporation
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methods
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Magnesium Silicates
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chemistry
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Mineral Fibers
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Nanofibers
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chemistry
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Transformation, Bacterial
10.Pathological studies of tissue damage in experimental rabbit liver cancer induced by energy controllable steep pulses.
Ping-ling WANG ; Li-na HU ; Xiao-jun YANG ; Jun LI ; Cai-xin SUN ; Lan XIONG ; Chen-guo YAO ; Shi-bin WANG
Chinese Journal of Hepatology 2005;13(7):516-519
OBJECTIVETo evaluate the efficacy of energy controllable steep pulses (ECSP) in the treatment of rabbit VX2 cancer implanted in livers.
METHODSA tumor model was successfully established using 30 rabbits. ECSP were applied to liver cancer in half of these rabbits and the rest were used as controls. After exposure to ECSP, tissues were obtained and subjected by routine HE and transmission electron microscopic (TEM) observation. The survival time of the animals and the statuses of each group were recorded.
RESULTSFrom pathological observations, ECSP showed effectively destructive action compared with that of the unexposed group. A clear borderline can be seen between necrotic cancer and its surrounding normal tissue. Irreversible cell changes were present under TEM. The survival periods of the experimental and control group were 83.1 days and 39.0 days respectively, and there was a significant difference between the two groups (Z = -2.943, P < 0.01).
CONCLUSIONECSP can effectively treat rabbit VX2 cancer implanted in the liver; also it is safe for its surrounding normal tissues. ECSP can be a useful method for local treatment of liver cancer.
Animals ; Electric Conductivity ; Electromagnetic Fields ; Electroporation ; methods ; Female ; Liver Neoplasms, Experimental ; pathology ; Male ; Rabbits