Biological autoluminescence enables effective monitoring of yeast cell electroporation.

The application of pulsed electric fields (PEFs) is becoming a promising tool for application in biotechnology, and the food industry. However, real-time monitoring of the efficiency of PEF treatment conditions is challenging, especially at the industrial scale and in continuous production conditions.  To overcome this challenge, we have developed a straightforward setup capable of real-time detection of yeast biological autoluminescence (BAL) during pulsing.

Kohonen Network-Based Adaptation of Non Sequential Data for Use in Convolutional Neural Networks.

Convolutional neural networks have become one of the most powerful computing tools of artificial intelligence in recent years. They are especially suitable for the analysis of images and other data that have an inherent sequence structure, such as time series data. In the case of data in the form of vectors of features, the order of which does not matter, the use of convolutional neural networks is not justified.

Biological autoluminescence as a noninvasive monitoring tool for chemical and physical modulation of oxidation in yeast cell culture.

Normal or excessive oxidative metabolism in organisms is essential in physiological and pathophysiological processes, respectively. Therefore, monitoring of biological oxidative processes induced by the chemical or physical stimuli is nowadays of extreme importance due to the environment overloaded with various physicochemical factors. Current techniques typically require the addition of chemical labels or light illumination, which perturb the samples to be analyzed.

Pulsating electromagnetic field stimulation prevents cell death of puromycin treated U937 cell line.

Aim of study was to verify whether pulsating electromagnetic field (PEMF) can affect cancer cells proliferation and death. U937 human lymphoid cell line at densities starting from 1 x 10(6) cells/ml to 0.0625 x 10(6) cells/ml, were exposed to a pulsating magnetic field 50 Hz, 45+/-5 mT three times for 3 h per each stimulation with 24 h intervals.

Intrarectal vaccination with recombinant vaccinia virus expressing carcinoembronic antigen induces mucosal and systemic immunity and prevents progression of colorectal cancer.

The gastrointestinal mucosa contains an intact immune system that protects the host from pathogens and communicates with the systemic immune system. Absorptive epithelial cells in the mucosa give rise to malignant tumors although the interaction between tumor cells and the mucosal immune system is not well defined. The pathophysiology of colorectal cancer has been elucidated through studies of hereditary syndromes, such as familial adenomatous polyposis, a cancer predisposition syndrome caused by germline mutations in the adenomatous polyposis coli tumor suppressor gene.

Flow cytometry application for studies on adenosine A2A receptors expression.

Adenosine A2A receptors belong to the heptaspanning membrane receptors family A, also known as G protein-coupled receptors. In human brain they are highly expressed in striatum, where they co-exist and co-function with adenosine A1, glutamate mGlu5 and dopamine D2 receptors. As glutaminergic neurotransmission modulators in GABAergic enkephalinergic neurons, adenosine A2A receptors are attractive targets for new, alternative therapies of neurodegenerative disorders, like Parkinson's disease and Huntington's disease.

Nitropolycyclic aromatic hydrocarbons are inducers of mitotic homologous recombination in the wing-spot test of Drosophila melanogaster.

In this study, the widespread environmental pollutants 1-nitronaphthalene (1NN), 1,5-dinitronaphthalene (1,5DNN), 2-nitrofluorene (2NF) and 9-nitroanthracene (9NA), were investigated for genotoxicity in the wing somatic mutation and recombination test (SMART) of Drosophila--using the high bioactivation (HB) cross. Our in vivo experiments demonstrated that all compounds assessed induced genetic toxicity, causing increased incidence of homologous somatic recombination. 2NF, 9NA and 1NN mutant clone induction is almost exclusively related to somatic recombination, although 1,5DNN-clone induction depends on both mutagenic and recombinagenic events.

The role of heme oxygenase-1 in down regulation of PGE2 production by taurine chloramine and taurine bromamine in J774.2 macrophages.

Taurine chloramine (TauCl) and taurine bromamine (TauBr), products of myeloperoxidase halide system, exert anti-inflammatory properties. TauCl was demonstrated to inhibit the production of a variety of pro-inflammatory mediators including cyclooxygenase-2 (COX-2) dependent production of prostaglandin E(2) (PGE(2)). Recently we have demonstrated that both major leukocyte haloamines, TauCl and TauBr, induced expression of HO-1 in non-activated and LPS-activated J774.

Improving tumor targeting and therapeutic potential of Salmonella VNP20009 by displaying cell surface CEA-specific antibodies.

Genetically modified Salmonella typhimurium VNP20009 (VNP) is a useful vehicle for cancer therapy and vaccine development but exhibits limited tumor targeting in vivo. We engineered a novel VNP derivative that expressed carcinoembryonic antigen (CEA)-specific single chain antibody fragments (scFv) on the cell surface to increase tumor-specific targeting. There was significant scFv cell surface display visualized by flow cytometry and confocal microscopy when cells were probed with fluorescently labeled CEA.

Immune properties of recombinant vaccinia virus encoding CD154 (CD40L) are determined by expression of virally encoded CD40L and the presence of CD40L protein in viral particles.

Expression of costimulatory molecules by recombinant poxviruses is a promising strategy for enhancing therapeutic vaccines. CD40-CD40L interactions are critical for conditioning dendritic cells (DC) and priming T- and B-cell immunity. We constructed a vaccinia virus expressing murine CD40L (rV-CD40L) and studied its immunomodulatory properties in vitro.

The HIV-1 HLA-A2-SLYNTVATL is a help-independent CTL epitope.

The CTL response to the HLA-A*0201-restricted, HIV-1 p17 Gag(77-85) epitope (SLYNTVATL; SL9) has been extensively studied in patients. Although this reactivity is exceptionally prominent in chronically infected patients and inversely correlated to viral load, SL9-specific CTLs (SL9-CTLs) are rarely detected in acute infection. To explore the cellular basis for this unusual manifestation, SL9-CTLs primed ex vivo from naive circulating CD8(+) T cells of healthy, seronegative donors were generated and characterized.

Reprogramming of TIMP-1 and TIMP-3 expression profiles in brain microvascular endothelial cells and astrocytes in response to proinflammatory cytokines.

Cytokine-dependent regulation of tissue inhibitors of metalloproteinases (TIMPs) expression provides an important mechanism for controlling the activity of matrix metalloproteinases. We present data indicating that during inflammatory processes TIMP-1 and TIMP-3 may be involved in the proteolytic remodeling of subendothelial basement membrane of the brain microvascular system, a key step during leukocyte migration into the brain perivascular tissue. In brain endothelial cells the expression of TIMP-1 is dramatically up-regulated by major proinflammatory cytokines, with the combination of interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF alpha) exhibiting the strongest synergistic stimulation.

Effect of cytokines on tumour cell-endothelial interactions.

The adherence of tumour cells to microvascular endothelium is believed to be a necessary step in their migration to sites of metastasis. It has been proposed that this process occurs when cell surface molecules on tumour cells bind to complementary sites on endothelial cells. The expression of these endothelial-derived cell adhesion molecules appears to be modulated by cytokines, a broad class of protein mediators which play important roles in immune and inflammatory reactions.

Inhibitory effect of di-catechol rooperol on VCAM-1 and iNOS expression in cytokine-stimulated endothelium.

Induced expression of vascular cell adhesion molecule-1 (VCAM-1) and of nitric oxide synthase (iNOS) is believed to play a role in the pathogenesis of atherosclerosis, asthma, as well as other inflammatory disorders. In the current study we examined the effect of the di-catechol rooperol [(E)-1,5-bis (3',4'-dihydroxyphenyl) pent-4-en-1-yne] on the process of microvascular endothelial cell (MME) activation by TNF-alpha and IFN-gamma. We show that rooperol decreases VCAM-1 and iNOS mRNA levels in cytokine-activated MME with subsequent inhibition of VCAM-1 membrane expression as measured by adhesion of P815 cells to MME monolayers, and NO production, as reflected in the nitrite concentration in culture medium.

Stimulatory effect of ouabain on VCAM-1 and iNOS expression in murine endothelial cells: involvement of NF-kappa B.

Endothelial cells play a pivotal role in the development of atherosclerosis. An 'activated' phenotype of these cells is manifested by signal transduction-dependent expression of genes encoding cytokines, pro- and anticoagulant factors, and cell adhesion molecules. In the current study we examined the effect of ouabain, an inhibitor of Na+/K(+)-ATPase, on the process of endothelial cell activation.

Stimulation of glyceraldehyde-3-phosphate dehydrogenase mRNA levels by endogenous nitric oxide in cytokine-activated endothelium.

Previous studies have shown that endogenous nitric oxide (NO) potentiates glycolysis in the cytokine-activated murine microvascular endothelial cells (MME). In the present study we investigate the influence of NO on the expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH), an enzyme of the glycolytic pathway. Activation of MME with TNF-alpha and IFN-gamma resulted in a strong elevation of GAPDH mRNA levels.

Methylxanthines and calcium-mobilizing agents inhibit the expression of cytokine-inducible nitric oxide synthase and vascular cell adhesion molecule-1 in murine microvascular endothelial cells.

In response to exposure to the inflammatory cytokines tumor necrosis factor-alpha (TNF) and interferon-gamma (IFN-gamma), murine brain microvascular endothelial cells (MME) synthesize the cell surface molecule, vascular cell adhesion molecule-1 (VCAM-1), and the intracellular enzyme, inducible nitric oxide synthase (iNOS). However, iNOS synthesis requires the presence of both TNF and IFN-gamma, while VCAM-1 can be induced by either cytokine alone. We examined the induction of VCAM-1 and iNOS under a variety of conditions to better define the regulation of TNF and IFN-gamma signal transduction pathways in MME.

Regulation of VCAM-1 expression and involvement in cell adhesion to murine microvascular endothelium.

The present studies were undertaken to examine the regulation of murine VCAM-1 expression and the involvement of this molecule in adhesive processes occurring on the surface of microvascular endothelium. Flow cytometric analyses revealed that murine microvascular endothelium (MME) in culture constitutively expresses VCAM-1 and that stimulation of MME by TNF, IL-1, or LPS, but not by PMA or staurosporine, strongly increased the surface expression of this cell adhesion molecule. Stimulation of VCAM-1 expression by TNF may be diminished by ionomycin as well as by inhibitors of protein kinases (H-7 and sangivamycin).

Low density lipoprotein inhibits accumulation of nitrites in murine brain endothelial cell cultures.

Endothelial cells produce nitric oxide which is considered to serve as a major source of endothelial derived relaxing factor activity. It has been demonstrated that activation of mouse brain endothelium by TNF-alpha and IFN-gamma led to accumulation of nitrite which is presumably formed by oxidation of nitric oxide. A number of studies suggest that reactive oxygen species produced by cytokine-activated cells are involved in the conversion of nitric oxide to nitrites and nitrates.

Inhibition of basal and tumor necrosis factor-enhanced binding of murine tumor cells to murine endothelium by transforming growth factor-beta 1.

The adherence of cells to microvascular endothelium is important in a number of processes, including inflammatory responses and metastasis. It has been demonstrated that in human models, cytokines such as TNF, IL-1, IFN-gamma increase the adhesiveness of endothelium for cells of the immune and inflammatory system by stimulating the expression of cell adhesion molecules on endothelial cell surfaces. We and others have shown similar cytokine-induced endothelial adhesiveness for tumor cells in murine and human models.

Effect of inflammatory cytokines on the adherence of tumor cells to endothelium in a murine model.

We have demonstrated that pretreatment of mouse brain microvascular endothelial cells (MBE) with tumor necrosis factor-alpha (TNF), IL-1, or LPS augmented the binding of P815 mastocytoma cells in vitro. The effect of these agents was dose and time dependent. PMA was able to mimic the influence of these factors to a limited degree.

Studies on the role of protein kinases in the TNF-mediated enhancement of murine tumor cell-endothelial cell interactions.

We have previously demonstrated that the exposure of mouse microvascular endothelium (MME) to tumor necrosis factor-alpha (TNF) led to the increased binding of mouse mastocytoma cells (P815) to endothelial monolayers (Bereta et al., in press). In the current study we examined the possible involvement of protein kinases in TNF signal transduction in the endothelial cells.

Isotype-like suppression of T cell-mediated immunity in vivo. II. Suppression of the early component of contact sensitivity by a Ly-2+ T cell-derived suppressor factor that binds to contact sensitivity-initiating, antigen-specific, Ly-1+ T cell-derived factors that are of different antigen specificities.

Recognition that delayed-type hypersensitivity (DTH) reactions, such as contact sensitivity (CS) in mice, are initiated by Ly-1+ T cell-derived, antigen-specific factors has led to identification of a new kind of suppressor T cell that regulates this initiation phase of CS. Regulation by these suppressor T cells is T cell isotype-like in that initiation of DTH of various antigenic specificities is suppressed, whereas, Ly-1+ T cells mediating the antigen/major histocompatibility complex-restricted, classic delayed phase of CS responses are not affected, nor are other T cell activities. This study shows that these isotype-specific suppressor T cells probably act by release of soluble, isotype-specific, suppressor factors.

Isotype-like suppression of T cell-mediated immunity in vivo. I. Delayed-type hypersensitivity specificity of T cell suppression induced by antigen-binding T cell factors that initiate contact sensitivity.

A new form of immunoregulation is described that is based on the recent suggestion that the effector phase of delayed-type hypersensitivity (DTH) responses consists of a cascade of steps that are dependent on the sequential action of two types of antigen-specific Ly-1+ effector cells. According to this formulation, which is based on analysis of contact sensitivity (CS) in mice, DTH consists of at least two T cell-dependent steps that must occur in sequence. The first of these steps occurs within 2 hr of challenge and depends on DTH-initiating, antigen-binding, antigen-specific T cell factors that sensitize the tissues for an obligatory initial vasoactive step, which allows the antigen/major histocompatibility complex (MHC)-restricted, Ly-1+ effector T cells of classic 24 to 48 hr DTH responses to enter the tissues and produce chemoattractant lymphokines.