Publications by authors named "Jiankui Chen"

18 Publications

  • Page 1 of 1

Positioning Error Limit for the Last Droplet Deposition into a Microcavity in the Manufacture of Printed OLEDs.

Langmuir 2021 Aug 29;37(31):9396-9404. Epub 2021 Jul 29.

State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, 430074 Wuhan, People's Republic of China.

In the manufacture of the emissive layer and the encapsulation layer of organic light-emitting diode panels, inkjet printing has the advantages of high material utilization, low cost, flexibility in patterning, and large-area production. Especially for emissive layer printing, the micro-pixel array brings a higher requirement of droplet positioning accuracy and volume of the liquid in a pixel. To achieve a uniform deposit morphology, several droplets are usually needed in the inkjet printing of emissive layers. As the printing process continues, these droplets coalesce, and its equilibrium outcome can be roughly approximated by a section of an ellipsoidal cap under the interaction of the surface tension and gravity. The existence of the "ellipsoidal cap" enlarges the spread, and the maximum allowable out-of-pixel spreading length is decreased because of the "ellipsoidal cap" in the neighboring pixel. In this research, the volume of fluid method is used to study the behavior of the last droplet deposition into the wetted microcavity. The effects of wettability, droplet deposition speed, and initial volume of the liquid in the pixel on the printable region are investigated, and printing parameter spaces that result in successful printing are established.
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http://dx.doi.org/10.1021/acs.langmuir.1c01058DOI Listing
August 2021

A host-based two-gene model for the identification of bacterial infection in general clinical settings.

Int J Infect Dis 2021 Apr 2;105:662-667. Epub 2021 Mar 2.

Department of Clinical Laboratory, 307th Hospital of Chinese People's Liberation Army, Beijing, China. Electronic address:

Objectives: In this study, we aimed to develop a simple gene model to identify bacterial infection, which can be implemented in general clinical settings.

Methods: We used a clinically availablereal-time quantitative polymerase chain reaction platform to conduct focused gene expression assays on clinical blood samples. Samples were collected from 2 tertiary hospitals.

Results: We found that the 8 candidate genes for bacterial infection were significantly dysregulated in bacterial infection and displayed good performance in group classification, whereas the 2 genes for viral infection displayed poor performance. A two-gene model (S100A12 and CD177) displayed 93.0% sensitivity and 93.7% specificity in the modeling stage. In the independent validation stage, 87.8% sensitivity and 96.6% specificity were achieved in one set of case-control groups, and 93.6% sensitivity and 97.1% specificity in another set.

Conclusions: We have validated the signature genes for bacterial infection and developed a two-gene model to identify bacterial infection in general clinical settings.
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http://dx.doi.org/10.1016/j.ijid.2021.02.112DOI Listing
April 2021

A Protein Corona Adsorbed to a Bacterial Magnetosome Affects Its Cellular Uptake.

Int J Nanomedicine 2020 6;15:1481-1498. Epub 2020 Mar 6.

CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China.

Purpose: It is well known that when exposed to human blood plasma, nanoparticles are predominantly coated by a layer of proteins, forming a corona that will mediate the subsequent cell interactions. Magnetosomes are protein-rich membrane nanoparticles which are synthesized by magnetic bacteria; these have gained a lot of attention owing to their unique magnetic and biochemical characteristics. Nevertheless, whether bacterial magnetosomes have a corona after interacting with the plasma, and how such a corona affects nanoparticle-cell interactions is yet to be elucidated. The aim of this study was to characterize corona formation around a bacterial magnetosome and to assess the functional consequences.

Methods: Magnetosomes were isolated from the magnetotactic bacteria, (MSR-1). Size, morphology, and zeta potential were measured by transmission electron microscopy and dynamic light scattering. A quantitative characterization of plasma corona proteins was performed using LC-MS/MS. Protein absorption was further examined by circular dichroism and the effect of the corona on cellular uptake was investigated by microscopy and spectroscopy.

Results: Various serum proteins were found to be selectively adsorbed on the surface of the bacterial magnetosomes following plasma exposure, forming a corona. Compared to the pristine magnetosomes, the acquired corona promoted efficient cellular uptake by human vascular endothelial cells. Using a protein-interaction prediction method, we identified cell surface receptors that could potentially associate with abundant corona components. Of these, one abundant corona protein, ApoE, may be responsible for internalization of the magnetosome-corona complex through LDL receptor-mediated internalization.

Conclusion: Our findings provide clues as to the physiological response to magnetosomes and also reveal the corona composition of this membrane-coated nanomaterial after exposure to blood plasma.
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http://dx.doi.org/10.2147/IJN.S220082DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7065717PMC
May 2020

Interaction of gold and silver nanoparticles with human plasma: Analysis of protein corona reveals specific binding patterns.

Colloids Surf B Biointerfaces 2017 Apr 20;152:317-325. Epub 2017 Jan 20.

Key Laboratory for Biological Effects of Nanomaterials and Nanosafety of Chinese Academy of Sciences, Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, P.R. China; University of Chinese Academy of Sciences, Beijing, 100049, P.R. China. Electronic address:

Determining how nanomaterials interact with plasma will assist in understanding their effects on the biological system. This work presents a systematic study of the protein corona formed from human plasma on 20nm silver and gold nanoparticles with three different surface modifications, including positive and negative surface charges. The results show that all nanoparticles, even those with positive surface modifications, acquire negative charges after interacting with plasma. Approximately 300 proteins are identified on the coronas, while 99 are commonly found on each nanomaterial. The 20 most abundant proteins account for over 80% of the total proteins abundance. Remarkably, the surface charge and core of the nanoparticles, as well as the isoelectric point of the plasma proteins, are found to play significant roles in determining the nanoparticle coronas. Albumin and globulins are present at levels of less than 2% on these nanoparticle coronas. Fibrinogen, which presents in the plasma but not in the serum, preferably binds to negatively charged gold nanoparticles. These observations demonstrate the specific plasma protein binding pattern of silver and gold nanoparticles, as well as the importance of the surface charge and core in determining the protein corona compositions. The potential downstream biological impacts of the corona proteins were also investigated.
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http://dx.doi.org/10.1016/j.colsurfb.2017.01.037DOI Listing
April 2017

Characterization and Genomic Analysis of Quinolone-Resistant Delftia sp. 670 Isolated from a Patient Who Died from Severe Pneumonia.

Curr Microbiol 2015 Jul 3;71(1):54-61. Epub 2015 May 3.

School of Basic Medical Science Central South University, Changsha, 410013, People's Republic of China,

Antibiotic-resistant opportunistic pathogens have become a serious concern in recent decades, as they are increasingly responsible for hospital-acquired infections. Here, we describe quinolone-resistant Delftia sp. strain 670, isolated from the sputum of a patient who died from severe pulmonary infection. The draft genome sequence of this strain was obtained by whole-genome shotgun sequencing, and was subjected to comparative genome analysis. Genome analysis revealed that one critical mutation (Ser83Ile in gyrA) might play a decisive role in quinolone resistance. The genome of Delftia sp. strain 670 contains both type II and type VI secretion systems, which were predicted to contribute to the virulence of the strain. Phylogenetic analysis, assimilation tests, and comparative genome analysis indicated that strain 670 differed from the four known Delftia species, suggesting this strain could represent a novel species. Although the study could not determine the strain 670 as the pathogen led to mortality, our findings also presented the pathogenic potential of Delftia species, and the increasing severity of antibiotic resistance among emerging opportunistic pathogens. The whole genome sequencing and comparative analysis improved our understanding of genome evolution in the genus Delftia, and provides the foundation for further study on drug resistance and virulence of Delftia strains.
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http://dx.doi.org/10.1007/s00284-015-0818-6DOI Listing
July 2015

Acute brucellosis with typical hemophagocytic lymphohistiocytosis accompanying elevated tumor markers.

Arch Iran Med 2014 Oct;17(10):722-3

Department of Laboratory Medicine, Affiliated hospital of Academy of Military Medical Sciences, Beijing 100071, PR China.

We reported a typical brucellosis, which was diagnosed as hemophagocytic lymphohistiocytosis (HLH). Although some tumor markers (CEA, CYFRA21-1, NSE, CA19-9) in the patient's serum were elevated, carcinomas were excluded by a variety of inspections including bone marrow aspirations, ultrasound examinations, and whole-body PET-CT scans. It was concluded that serum tumor markers are considered medically necessary as a screening test for brucellosis with HLH, however, detailed inspections were needed to make a final diagnosis. Moreover, combination of epidemiology investigations and laboratory inspections were helpful to determine the etiology of HLH and initiate the corresponding treatments.
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http://dx.doi.org/0141710/AIM.0014DOI Listing
October 2014

Characterization of the morphology and genome of an Escherichia coli podovirus.

Arch Virol 2014 Dec 28;159(12):3249-56. Epub 2014 Aug 28.

State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China.

Escherichia coli is an important opportunistic pathogen. It can cause sepsis and severe infection. The application of lytic bacteriophages to treat infectious diseases is an alternative to antibiotics. A lytic Escherichia coli phage, designated IME-EC2, was isolated from hospital sewage. Transmission electron microscopy revealed that IME-EC2 to be a member of the family Podoviridae. It had a 60-nm head and a 15-nm tail. Here, we present the complete genome sequence of this phage, which consists of 41,510 bp with an overall G+C content of 59.2 %. A total of 60 coding sequences (CDS) were identified, and the phage genome does not contain any tRNA genes. Forty percent of the unknown CDSs are unique to IME-EC2. This phage does not show significant similarity to other phages at the DNA level, which suggests that IME-EC2 could be a novel phage. One of the unique features identified in the IME-EC2 genome was a gene coding for a putative colanic-acid-degrading protein, which could allow the phage to degrade bacterial capsule and biofilms. Another unique feature is that IME-EC2 does not contain a terminase small subunit, which suggests that this phage may have a unique packaging mechanism. The present work provides novel information on phages and shows that this lytic phage or its products could be exploited to destroy bacterial biofilms and pathogenic E. coli.
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http://dx.doi.org/10.1007/s00705-014-2189-xDOI Listing
December 2014

Betaine homocysteine methyltransferase (BHMT) as a specific and sensitive blood marker for acute liver injury.

Biomarkers 2014 Nov 21;19(7):578-84. Epub 2014 Aug 21.

National Center for Nanoscience and Technology , Beijing , P.R. China .

We developed a high-performance ELISA assay and measured serum BHMT levels in healthy individuals and patients with acute liver injury (ALI). The detection range of this ELISA assay was from 1.56 to 100 ng/ml. BHMT levels are significantly higher in ALI groups. In the healthy group (n = 244), the median value (interquartile range, IQR 0-56.40) was 1.83 ng/ml. In the ALI group (n = 42), the median value of BHMT was 748.48 ng/ml (IQR, 0-51095.92). ROC curve analysis demonstrated good sensitivity (0.86) and specificity (0.98). In addition, in five ALI cases with time course samples available, BHMT and ALT both followed the "rise and fall" temporal pattern with the disease progression. However, the slopes of BHMT curves were steeper than ALT curves. And in three out of the five cases, BHMT levels peaked 1 day earlier than ALT levels be a sensitive marker with good prognostic value.
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http://dx.doi.org/10.3109/1354750X.2014.951880DOI Listing
November 2014

Quantitative liver-specific protein fingerprint in blood: a signature for hepatotoxicity.

Theranostics 2014 14;4(2):215-28. Epub 2014 Jan 14.

2. Institute for Systems Biology, 401 Terry Avenue N, Seattle, Washington 98109, USA.

We discuss here a new approach to detecting hepatotoxicity by employing concentration changes of liver-specific blood proteins during disease progression. These proteins are capable of assessing the behaviors of their cognate liver biological networks for toxicity or disease perturbations. Blood biomarkers are highly desirable diagnostics as blood is easily accessible and baths virtually all organs. Fifteen liver-specific blood proteins were identified as markers of acetaminophen (APAP)-induced hepatotoxicity using three proteomic technologies: label-free antibody microarrays, quantitative immunoblotting, and targeted iTRAQ mass spectrometry. Liver-specific blood proteins produced a toxicity signature of eleven elevated and four attenuated blood protein levels. These blood protein perturbations begin to provide a systems view of key mechanistic features of APAP-induced liver injury relating to glutathione and S-adenosyl-L-methionine (SAMe) depletion, mitochondrial dysfunction, and liver responses to the stress. Two markers, elevated membrane-bound catechol-O-methyltransferase (MB-COMT) and attenuated retinol binding protein 4 (RBP4), report hepatic injury significantly earlier than the current gold standard liver biomarker, alanine transaminase (ALT). These biomarkers were perturbed prior to onset of irreversible liver injury. Ideal markers should be applicable for both rodent model studies and human clinical trials. Five of these mouse liver-specific blood markers had human orthologs that were also found to be responsive to human hepatotoxicity. This panel of liver-specific proteins has the potential to effectively identify the early toxicity onset, the nature and extent of liver injury and report on some of the APAP-perturbed liver networks.
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http://dx.doi.org/10.7150/thno.7868DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3900804PMC
September 2014

Characterization of Enterococcus faecalis phage IME-EF1 and its endolysin.

PLoS One 2013 13;8(11):e80435. Epub 2013 Nov 13.

State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China.

Enterococcus faecalis is increasingly becoming an important nosocomial infection opportunistic pathogen. E. faecalis can easily obtain drug resistance, making it difficult to be controlled in clinical settings. Using bacteriophage as an alternative treatment to drug-resistant bacteria has been revitalized recently, especially for fighting drug-resistant bacteria. In this research, an E. faecalis bacteriophage named IME-EF1 was isolated from hospital sewage. Whole genomic sequence analysis demonstrated that the isolated IME-EF1 belong to the Siphoviridae family, and has a linear double-stranded DNA genome consisting of 57,081 nucleotides. The IME-EF1 genome has a 40.04% G+C content and contains 98 putative coding sequences. In addition, IME-EF1 has an isometric head with a width of 35 nm to 60 nm and length of 75 nm to 90 nm, as well as morphology resembling a tadpole. IME-EF1 can adsorb to its host cells within 9 min, with an absorbance rate more than 99% and a latent period time of 25 min. The endolysin of IME-EF1 contains a CHAP domain in its N-terminal and has a wider bactericidal spectrum than its parental bacteriophage, including 2 strains of vancomycin-resistant E. faecalis. When administrated intraperitoneally, one dose of IME-EF1 or its endolysin can reduce bacterial count in the blood and protected the mice from a lethal challenge of E. faecalis, with a survival rate of 60% or 80%, respectively. Although bacteriophage could rescue mice from bacterial challenge, to the best of our knowledge, this study further supports the potential function of bacteriophage in dealing with E. faecalis infection in vivo. The results also indicated that the newly isolated bacteriophage IME-EF1 enriched the arsenal library of lytic E. faecalis bacteriophages and presented another choice for phage therapy in the future.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0080435PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3827423PMC
July 2014

Complete Genome Sequence of IME13, a Stenotrophomonas maltophilia bacteriophage with large burst size and unique plaque polymorphism.

J Virol 2012 Oct;86(20):11392-3

Beijing Institute of Microbiology and Epidemiology, Fengtai District, Beijing.

Stenotrophomonas maltophilia bacteriophage IME13 is a virulent phage with a large burst size, exceeding 3,000, much larger than that of any other stenotrophomonas phage reported before. It showed effective lysis of Stenotrophomonas maltophilia. Additionally, the phage IME13 developed at least three obviously different sizes of plaques when a single plaque was picked out and inoculated on a double-layer Luria broth agar plate with its host. Here we announce its complete genome and describe major findings from its annotation.
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http://dx.doi.org/10.1128/JVI.01908-12DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3457173PMC
October 2012

Signal peptide and denaturing temperature are critical factors for efficient mammalian expression and immunoblotting of cannabinoid receptors.

J Huazhong Univ Sci Technolog Med Sci 2012 Apr 20;32(2):299-302. Epub 2012 Apr 20.

Department of Clinical Laboratory, No. 307 Hospital, Academy of Military Medical Sciences, Beijing, 100071, China.

Many researchers employed mammalian expression system to artificially express cannabinoid receptors, but immunoblot data that directly prove efficient protein expression can hardly be seen in related research reports. In present study, we demonstrated cannabinoid receptor protein was not able to be properly expressed with routine mammalian expression system. This inefficient expression was rescued by endowing an exogenous signal peptide ahead of cannabinoid receptor peptide. In addition, the artificially synthesized cannabinoid receptor was found to aggregate under routine sample denaturing temperatures (i.e., ≥95°C), forming a large molecular weight band when analyzed by immuno-blotting. Only denaturing temperatures ≤75°C yielded a clear band at the predicted molecular weight. Collectively, we showed that efficient mammalian expression of cannabinoid receptors need a signal peptide sequence, and described the requirement for a low sample denaturing temperature in immuno-blot analysis. These findings provide very useful information for efficient mammalian expression and immuno-blotting of membrane receptors.
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http://dx.doi.org/10.1007/s11596-012-0052-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3703952PMC
April 2012

Circulating microRNA-122 as a potential biomarker for liver injury.

Mol Med Rep 2012 Jun 15;5(6):1428-32. Epub 2012 Mar 15.

School of Life Science, Zhejiang Sci-Tech University, Hangzhou, Zhejiang , People's Republic of China.

Liver-specific microRNA-122 (miR-122) is involved in the replication of hepatitis C virus (HCV) and its potential as a target for antiviral intervention was recently assessed. However, the use of circulating miR-122 in the evaluation of liver function has never been reported. In the present study, changes of serum miRNA levels were first evaluated in acute human hepatotoxicity due to paraquat exposure. Serum samples were collected and analyzed using real-time reverse transcription PCR. The results showed a positive correlation between serum miR-122 and alanine aminotransferase, a clinical biomarker for liver function. Furthermore, serum miR-122 was assessed in patients with hepatitis B and hepatocarcinoma, resulting in distinct miR-122 profiles in these two closely related diseases. In addition to miR-122, another small RNA, U6 small nuclear RNA, was downregulated in hepatocarcinoma patients, suggesting its prognostic significance in this disease. Taken together, these lines of evidence indicate that serum miR-122 may provide a biomarker for diverse liver diseases and, more importantly, suggest that a combination of nucleic acid biomarkers may be used as a sensitive and specific index for discriminating closely related diseases.
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http://dx.doi.org/10.3892/mmr.2012.838DOI Listing
June 2012

Rapid genetic characterization of a novel Enterobacteria phage and determination of its host recognizing genes.

Sheng Wu Gong Cheng Xue Bao 2011 Jun;27(6):884-90

State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China.

We isolated a novel Enterobacteria phage IME08 from hospital sewage, then confirmed it was a double-stranded DNA phage by digesting its genetic material with DNase I, RNase A and several restriction endonucleases respectively. BLAST results of random fragments generated by a random PCR cloning method revealed that it belonged to T4-like virus. We subsequently determined the host recognizing genes (g37 and g38) sequence with a PCR-based "genome jumping" protocol based on highly conserved region at 5' terminus of g37 from four other T4-like Bacteriophages (T4, JS98, T2 and K3). These molecular biological methods enabled us to readily characterize the bacteriophage and efficiently determine the sequence of the genes of interest based on very limited conserved sequence information.
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June 2011

The complete genome sequence of a novel T4-like bacteriophage, IME08.

Arch Virol 2011 Aug 26;156(8):1489-92. Epub 2011 May 26.

State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China.

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http://dx.doi.org/10.1007/s00705-011-1033-9DOI Listing
August 2011

Sequence characteristics of T4-like bacteriophage IME08 benome termini revealed by high throughput sequencing.

Virol J 2011 Apr 27;8:194. Epub 2011 Apr 27.

Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China.

Background: T4 phage is a model species that has contributed broadly to our understanding of molecular biology. T4 DNA replication and packaging share various mechanisms with human double-stranded DNA viruses such as herpes virus. The literature indicates that T4-like phage genomes have permuted terminal sequences, and are generated by a DNA terminase in a sequence-independent manner;

Methods: genomic DNA of T4-like bacteriophage IME08 was subjected to high throughput sequencing, and the read sequences with extraordinarily high occurrences were analyzed;

Results: we demonstrate that both the 5' and 3' termini of the IME08 genome starts with base G or A. The presence of a consensus sequence TTGGA|G around the breakpoint of the high frequency read sequences suggests that the terminase cuts the branched pre-genome in a sequence-preferred manner. Our analysis also shows that terminal cleavage is asymmetric, with one end cut at a consensus sequence, and the other end generated randomly. The sequence-preferred cleavage may produce sticky-ends, but with each end being packaged with different efficiencies;

Conclusions: this study illustrates how high throughput sequencing can be used to probe replication and packaging mechanisms in bacteriophages and/or viruses.
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http://dx.doi.org/10.1186/1743-422X-8-194DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3105952PMC
April 2011

[The electroporation effects of high power pulse microwave and electromagnetic pulse irradiation on the membranes of cardiomyocyte cells and the mechanism therein involved].

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi 2005 Aug;22(4):672-6, 694

Foshan Science Technology University, Foshan 528231, China.

Though there is ongoing public concern on potential hazards and risk of electromagnetic radiation, the bioeffects mechanism of electromagnetic fields remains obscure. Heart is one of the organs susceptive to electromagnetic fields (EMF). This study was designed to assess the influence of high power pulse microwave and electromagnetic pulse irradiation on cardiomyocytes, to explore the critical mechanism of electromagnetic fields, and to explain the regular course of injury caused by exposure to pulse EMF. Cultured cardiomyocytes were irradiated by high power pulse microwave and electromagnetic pulse first, then a series of apparatus including atom force microscope, laser scanning confocal microscope and flow cytometer were used to examine the changes of cell membrane conformation, structure and function. After irradiation, the cardiomyocytes pulsated slower or stop, the cells conformation was abnormal, the cells viability declined, and the percentage of apoptosis and necrosis increased significantly (P< 0.01). The cell membrane had pores unequal in size, and lost its penetration character. The concentration of Na+, K+, Ca2+, Cl-, Mg2+, Ca2+ and P3+ in cell culture medium increased significantly (P< 0.01). and the concentration of Ca2+ in cells ([Ca2+]i) decreased significantly (P<0.01). The results indicated that cardiomyocytes are susceptible to non-ionizing radiation. Pulse electromagnetic field can induce cardiomyocytes electroporation, and can do great damage to cells conformation, structure and function. Electroporation is one of the most critical mechanisms to explain the athermal effects of electromagnetic radiation.
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August 2005
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