A novel application for non-thermal plasma is the induction of immunogenic cancer cell death for cancer immunotherapy. Cells undergoing immunogenic death emit danger signals which facilitate anti-tumor immune responses. Although pathways leading to immunogenic cell death are not fully understood; oxidative stress is considered to be part of the underlying mechanism. Here; we studied the interaction between dielectric barrier discharge plasma and cancer cells for oxidative stress-mediated immunogenic cell death. We assessed changes to the intracellular oxidative environment after plasma treatment and correlated it to emission of two danger signals: surface-exposed calreticulin and secreted adenosine triphosphate. Plasma-generated reactive oxygen and charged species were recognized as the major effectors of immunogenic cell death. Chemical attenuators of intracellular reactive oxygen species successfully abrogated oxidative stress following plasma treatment and modulated the emission of surface-exposed calreticulin. Secreted danger signals from cells undergoing immunogenic death enhanced the anti-tumor activity of macrophages. This study demonstrated that plasma triggers immunogenic cell death through oxidative stress pathways and highlights its potential development for cancer immunotherapy.

Background:Chronic fatigue syndrome (CFS) is a multisystem disease, the pathogenesis of which remains undetermined.Aims:To test the hypothesis that there are reproducible abnormalities of gene expression in patients with CFS compared with normal healthy persons.Methods:To gain further insight into the pathogenesis of this disease, gene expression was analysed in peripheral blood mononuclear cells from 25 patients with CFS diagnosed according to the Centers for Disease Control criteria and 25 normal blood donors matched for age, sex, and geographical location, using a single colour microarray representing 9522 human genes. After normalisation, average difference values for each gene were compared between test and control groups using a cutoff fold difference of expression ⩾ 1.5 and a p value of 0.001. Genes showing differential expression were further analysed using Taqman real time polymerase chain reaction (PCR) in fresh samples.Results:Analysis of microarray data revealed differential expression of 35 genes. Real time PCR confirmed differential expression in the same direction as array results for 16 of these genes, 15 of which were upregulated (ABCD4, PRKCL1, MRPL23, CD2BP2, GSN, NTE, POLR2G, PEX16, EIF2B4, EIF4G1, ANAPC11, PDCD2, KHSRP, BRMS1, and GABARAPL1) and one of which was downregulated (IL-10RA). This profile suggests T cell activation and perturbation of neuronal and mitochondrial function. Upregulation of neuropathy target esterase and eukaryotic translation initiation factor 4G1 may suggest links with organophosphate exposure and virus infection, respectively.Conclusion:These results suggest that patients with CFS have reproducible alterations in gene regulation.

In order to obtain insight into the aetiology and pathogenesis of amyotrophic lateral sclerosis (ALS), high-density gene discovery arrays (GDA human version 1.2) containing 18 400 non-redundant EST cDNAs pooled from different tissue libraries have been used to monitor gene expression in lumbar spinal cord from ALS cases compared with controls. Quantitative filter analysis revealed differential expression of cDNAs normalized to internal standards. These candidates have been further investigated and their expression in spinal cord characterized in a panel of ALS and control subjects. Significant differential expression was obtained for 14 genes, 13 being elevated (up to six-fold) and one decreased (by 80%) in ALS. Amongst those elevated in ALS were thioredoxin and glial fibrilary acid protein, which have already been shown to be up-regulated in ALS, thus supporting the reliability of this approach. The other differentially regulated transcripts confirmed in the expression studies represent potential candidates in ALS pathogenesis being involved in antioxidant systems, neuroinflammation, the regulation of motor neurone function, lipid metabolism, protease inhibition and protection against apoptosis. The use of the GDA system has greatly facilitated the screening and retrieval of sequence information and has generated useful information on the cascade of molecular events occurring in ALS and potentially may highlight new candidates playing a role in the aetiology and progression of this disease.

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In order to obtain insight into the aetiology and pathogenesis of amyotrophic lateral sclerosis (ALS), high‐density gene discovery arrays (GDA human version 1.2) containing 18 400 non‐redundant EST cDNAs pooled from different tissue libraries have been used to monitor gene expression in lumbar spinal cord from ALS cases compared with controls. Quantitative filter analysis revealed differential expression of cDNAs normalized to internal standards. These candidates have been further investigated and their expression in spinal cord characterized in a panel of ALS and control subjects. Significant differential expression was obtained for 14 genes, 13 being elevated (up to six‐fold) and one decreased (by 80%) in ALS. Amongst those elevated in ALS were thioredoxin and glial fibrilary acid protein, which have already been shown to be up‐regulated in ALS, thus supporting the reliability of this approach. The other differentially regulated transcripts confirmed in the expression studies represent potential candidates in ALS pathogenesis being involved in antioxidant systems, neuroinflammation, the regulation of motor neurone function, lipid metabolism, protease inhibition and protection against apoptosis. The use of the GDA system has greatly facilitated the screening and retrieval of sequence information and has generated useful information on the cascade of molecular events occurring in ALS and potentially may highlight new candidates playing a role in the aetiology and progression of this disease.

The generation of reactive oxygen and nitrogen species (RONS) has been found to occur during inflammatory procedures, during cell ischemia, and in various crucial developmental processes such as cell differentiation and along cell signaling pathways. The most common sources of intracellular RONS are the mitochondrial electron transport system, NADH oxidase, and cytochrome P450. In this review, we analyzed the extracellular and intracellular sources of reactive species, their cell signaling pathways, the mechanisms of action, and their positive and negative effects in the dental field. In dentistry, ROS can be found—in lasers, photosensitizers, bleaching agents, cold plasma, and even resin cements, all of which contribute to the generation and prevalence of ROS. Nonthermal plasma has been used as a source of ROS for biomedical applications and has the potential for use with dental stem cells as well. There are different types of dental stem cells, but their therapeutic use remains largely untapped, with the focus currently on only periodontal ligament stem cells. More research is necessary in this area, including studies about ROS mechanisms with dental cells, along with the utilization of reactive species in redox medicine. Such studies will help to provide successful treatment modalities for various diseases.

ZnO nanostructures of diverse shape were grown via a solution process with different precursors and conditions. Morphological investigation of the nanostructures was carried out using field emission scanning electron microscopy and transmission microscopy observations and revealed that the nanostructures exhibit a wurtzite phase with an ideal lattice fringe distance of approximately 0.52 nm. The powder crystallinity was examined via X-ray diffraction spectroscopy. Screening results from anticancer studies of the effects on human brain tumor U87, cervical cancer HeLa, and normal HEK cells of ZnO nanostructures of diverse shape were obtained and indicate promising activity that varies with changes in the structure and the size of the particles. Treatment-induced cell death [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and survival assay], growth inhibition, cytogenetic damage (formation of micronuclei), and apoptosis were studied as parameters for the cellular response. Treatment with nanostructures enhanced growth inhibition and cell death in a concentration-dependent manner in both U87 and HeLa cell lines. At higher concentrations (above 15.6 μg/ml) the cytotoxic effects of the nanoparticles were highly synergistic and mainly mediated through apoptosis, implying the possible interactions of lesions caused by the agents. The enhanced cell death due to nanoparticles was accompanied by a significant increase (2-3 fold at 31.25 μg/ml) in the formation of micronuclei in U87 cells. The increase in the formation of micronuclei observed after treatment indicates that these structures may interfere with the rejoining of DNA strand breaks. Among all the nanostructures, nanoparticles and sheets exhibited potent activity against both HeLa and U87 cells. However, despite potent in vitro activity, all nanostructures exhibited diminished cytotoxicity against normal human HEK cells at all effective concentrations.

Induction of micronucleus formation (cytogenetic damage) in brain cancer cells upon exposure of dielectric barrier discharge plasma has been investigated. We have investigated the influence of exposure and incubation times on T98G brain cancer cells by using growth kinetic, clonogenic, and micronucleus formation assay. We found that micronucleus formation rate directly depends on the plasma exposure time. It is also shown that colony formation capacity of cells has been inhibited by the treatment of plasma at all doses. Cell death and micronucleus formation are shown to be significantly elevated by 120 and 240 s exposure of dielectric barrier discharge plasma.