Apoptosis in Postmortal Tissues of Goat Spinal Cords and Survival of Resident Neural Progenitors.

Growing demand for therapeutic tissue repair recurrently focusses scientists' attention on critical assessment of postmortal collection of live cells, especially stem cells. Our study aimed to assess the survival of neuronal progenitors in postmortal spinal cord and their differentiation potential. Postmortal samples of spinal cords were obtained from human-sized animals (goats) at 6, 12, 24, 36, and 54 h after slaughter.

Thermospheric parameters contribution to the formation of Yakutsk F-layer diurnal summer time anomaly.

The role of thermospheric neutral composition in the formation of the Yakutsk diurnal summer time foF anomaly is analyzed. Ionospheric stations inside and outside the anomaly area are considered. The effect of neutral composition in foF is the most noticeable around noontime hours.

Influence of the perfusion bioreactor on Stratified and Distributed approaches for multilayered tissue engineering on biodegradable scaffolds.

Despite wide use and approval of poly lactic-coglycolic acid (PLGA) for surgical applications, there have been very few studies on tissue constructions that mimic physiological multilayer structures by combining PLGA scaffolds with tissue engineering. In our study, we developed a bioreactor system to maintain, and to train two types of three-layered vascular-like structures. Then we examined how the perfusion conditions and different tissue engineering approaches affected the formation of the layered structure and degradation of the PLGA scaffolds.

Dynamic flow priming programs allow tuning up the cell layers properties for engineered vascular graft.

Tissue engineered vascular grafts (TEVG) are potentially clear from ethical and epidemiological concerns sources for reconstructive surgery for small diameter blood vessels replacement. Here, we proposed a novel method to create three-layered TEVG on biocompatible glass fiber scaffolds starting from flat sheet state into tubular shape and to train the resulting tissue by our developed bioreactor system. Constructed tubular tissues were matured and trained under 3 types of individual flow programs, and their mechanical and biological properties were analyzed.

Lung cancer increases HO concentration in the exhaled breath condensate, extent of mtDNA damage, and mtDNA copy number in buccal mucosa.

We have shown that the HO concentration in exhaled breath condensate (EBC) in lung cancer patients increases significantly compared to the EBC of healthy people and revealed the correlation between the HO level in the EBC and amount of mtDNA damage in buccal mucosa cells. The HO hyper-production may trigger mitochondrial biogenesis, thereby resulting in an increase in mtDNA copy number. However, we did not observe a significant difference in the studied parameters between smokers and non-smokers.

Daytime mid-latitude F-layer Q-disturbances: A formation mechanism.

Negative and positive near noontime prolonged (≥3 hours) F-layer Q-disturbances with deviations in NF > 35% occurred at Rome have been analyzed using aeronomic parameters inferred from f (plasma frequency at 180 km height) and fF observations. Both types of NF perturbations occur under quiet (daily Ap < 15 nT) geomagnetic conditions. Day-to-day atomic oxygen [O] variations at F-region heights specify the type (positive or negative) of Q-disturbance.

Long-term safety of the carbon fiber as an implant scaffold material.

Permanent therapeutically placed implants often used in situations when regeneration or transplantation are not practical or possible. They include metallic grafts for osteosynthesis, bulk metallic glasses, ceramics, and non-resorbable polymers providing mechanical support. Repair of the tissues on micro scale can also benefit from the biocompatible permanent implants.

Longitudinal variations in thermospheric parameters under summer noontime conditions inferred from ionospheric observations: A comparison with empirical models.

Longitudinal variations in the thermospheric neutral composition ([O] and [N]) and exospheric temperature Tex have been inferred from June monthly median noontime fF and fF observations at mid-latitudes to check for consistency with empirical MSIS models. In general, a similarity in longitudinal variations has been demonstrated, and this is interesting, as similar variations were obtained with very different methods and different data sources. Both inferred and MSISE-00 modelled height-integrated O/N ratios are comparable to TIMED/GUVI observations only under solar minimum conditions but differ substantially under high solar activity.

Cell penetrating caspase substrates promote survival of the transplanted cells.

Objective: Cell survival in critical post-transplantation period is challenged by inflammation, lack of vascularization, and insufficient cell attachment anchoring. Temporally blocking cell death may increase cell survival, but it is important to possess no risks of sustained cell death signal blocking and possible malignant transformations. Regarding apoptotic cell death, multi-micromolar overloading the cell with competitive caspase substrates delays the effects of actual downstream enzyme activation processing.

Donation of neural stem cells? Post mortal viability of spinal cord neuronal cells.

Transplantation of cells into central nervous system (CNS) shows a potential for treatment of post-traumatic and neurodegenerative diseases. Cadaver-derived neural cells can help reducing deficit of allogeneic material ready for transplantation. In this study we analyze post-mortal survival of spinal cord neural cells.

Peptide-functionalized chitosan-DNA nanoparticles for cellular targeting.

Chitosan-pDNA nanoparticles with various weight ratios (chitosan:pDNA 1:4-8:1) were characterized for particle size, zeta potential, morphology, and pDNA binding efficiency. For targeted gene delivery applications, nanoparticles were functionalized by coupling fluorescent dye and tyrosine kinase receptor B (TrkB) binding peptides on the particle surface. The targetability of the peptide-functionalized nanoparticles was demonstrated in TrkB positive murine transformed monocyte/macrophage cells (RAW 264).

Modeling reveals that dynamic regulation of c-FLIP levels determines cell-to-cell distribution of CD95-mediated apoptosis.

The expression levels of caspase-8 inhibitory c-FLIP proteins play an important role in regulating death receptor-mediated apoptosis, as their concentration at the moment when the death-inducing signaling complex (DISC) is formed determines the outcome of the DISC signal. Experimental studies have shown that c-FLIP proteins are subject to dynamic turnover and that their stability and expression levels can be rapidly altered. Even though the influence of c-FLIP on the apoptotic behavior of a single cell has been captured in mathematical simulation studies, the effect of c-FLIP turnover and stability has not been investigated.

Phosphopeptide enrichment with stable spatial coordination on a titanium dioxide coated glass slide.

Recent advances in phosphoproteomics have established powerful tools to analyze phosphorylation events. However, their spatial localization is lost due to sample homogenization procedures prior to the analysis. Imaging mass spectrometry (IMS) has emerged as a method to visualize the spatial distribution of molecules in tissue samples, but its application is still limited to relatively abundant molecules.

Opposing roles for caspase and calpain death proteases in L-glutamate-induced oxidative neurotoxicity.

Oxidative glutamate toxicity in HT22 murine hippocampal cells is a model for neuronal death by oxidative stress. We have investigated the role of proteases in HT22 cell oxidative glutamate toxicity. L-glutamate-induced toxicity was characterized by cell and nuclear shrinkage and chromatin condensation, yet occurred in the absence of either DNA fragmentation or mitochondrial cytochrome c release.

CD73 participates in cellular multiresistance program and protects against TRAIL-induced apoptosis.

The molecular mechanisms underlying the multiresistant phenotype of leukemic and other cancer cells are incompletely understood. We used expression arrays to reveal differences in the gene expression profiles of an apoptosis-resistant T cell leukemia clone (A4) and normally apoptosis-sensitive parental Jurkat cells. CD73 (ecto-5'-nucleotidase) was the most up-regulated gene in the resistant A4 cell clone.

The detection of micromolar pericellular ATP pool on lymphocyte surface by using lymphoid ecto-adenylate kinase as intrinsic ATP sensor.

Current models of extracellular ATP turnover include transient release of nanomolar ATP concentrations, triggering of signaling events, and subsequent ectoenzymatic inactivation. Given the high substrate specificity for adenylate kinase for reversible reaction (ATP + AMP <--> 2ADP), we exploited lymphoid ecto-adenylate kinase as an intrinsic probe for accurate sensing pericellular ATP. Incubation of leukemic T- and B-lymphocytes with [3H]AMP or [alpha-32P]AMP induces partial nucleotide conversion into high-energy phosphoryls.

Live cell detection of caspase-3 activation by a Discosoma-red-fluorescent-protein-based fluorescence resonance energy transfer construct.

A probe consisting of Discosoma red fluorescent protein (DsRed) and enhanced yellow fluorescent protein (EYFP) linked by a 19-amino-acid chain containing the caspase-3 cleavage site Asp-Glu-Val-Asp was developed to monitor caspase-3 activation in living cells. The expression of the tandem construct in mammalian cells yielded a strong red fluorescence when excited with 450- to 490-nm light or with a 488-nm argon ion laser line as a result of fluorescence resonance energy transfer (FRET) from donor EYFP to acceptor DsRed. The advantage over previous constructs using cyan fluorescent protein is that our construct can be used when excitation wavelengths lower than 488nm are not available.

Type-2A protein phosphatase activity is required to maintain death receptor responsiveness.

Type-2A protein phosphatase (PP2A) is a key regulator in many different cell signaling pathways and an important determinant in tumorigenesis. One of the signaling targets of PP2A is the mitogen-activated protein kinase (MAPK/ERK) cascade. In this study, we wanted to determine whether PP2A could be involved in regulation of death receptor activity through its capacity to regulate MAPK/ERK.

Cdk5 regulates the organization of Nestin and its association with p35.

The intermediate filament protein nestin is characterized by its specific expression during the development of neuronal and myogenic tissues. We identify nestin as a novel in vivo target for cdk5 and p35 kinase, a critical signaling determinant in development. Two cdk5-specific phosphorylation sites on nestin, Thr-1495 and Thr-316, were established, the latter of which was used as a marker for cdk5-specific phosphorylation in vivo.

Phosphorylation of serine 303 is a prerequisite for the stress-inducible SUMO modification of heat shock factor 1.

The heat shock response, which is accompanied by a rapid and robust upregulation of heat shock proteins (Hsps), is a highly conserved protection mechanism against protein-damaging stress. Hsp induction is mainly regulated at transcriptional level by stress-inducible heat shock factor 1 (HSF1). Upon activation, HSF1 trimerizes, binds to DNA, concentrates in the nuclear stress granules, and undergoes a marked multisite phosphorylation, which correlates with its transcriptional activity.

Synthesis and organotropism of 3H-dihydro derivatives of the cyanobacterial peptide hepatotoxin nodularin.

Tritium-labelled dihydro derivatives of the cyanobacterial peptide hepatotoxin nodularin were prepared by reduction with sodium boro[3H]hydride. The optimised reaction gave two dihydronodularin stereoisomers which were purified by high-performance liquid chromatography with a mobile phase of methanol-0.7% sodium sulfate (6:4) and a C(18) stationary phase.

Identification of ATP-synthase as a novel intracellular target for microcystin-LR.

Microcystins (MCs) are a group of closely related cyclic heptapeptides produced by a variety of common cyanobacteria. These are potent and highly specific hepatotoxins, the toxicity of which is based upon their inhibition of type-1 (PP1) and type-2A (PP2A) protein phosphatases. Apart from protein phosphatases, it is not known whether these phosphatase-inhibiting peptides could bind any other cellular proteins.