Double hadron leptoproduction in the nuclear medium

First measurement of double-hadron production in deep-inelastic scattering has been measured with the HERMES spectrometer at HERA using a 27.6 GeV positron beam with deuterium, nitrogen, krypton and xenon targets. The influence of the nuclear medium on the ratio of double-hadron to single-hadron yields has been investigated. Nuclear effects are clearly observed but with substantially smaller magnitude and reduced $A$-dependence compared to previously measured single-hadron multiplicity ratios. The data are in fair agreement with models based on partonic or pre-hadronic energy loss, while they seem to rule out a pure absorptive treatment of the final state interactions. Thus, the double-hadron ratio provides an additional tool for studying modifications of hadronization in nuclear matter

FGFR4 Arg388 allele correlates with tumour thickness and FGFR4 protein expression with survival of melanoma patients

A single nucleotide polymorphism in the gene for FGFR4 (−Arg388) has been associated with progression in various types of human cancer. Although fibroblast growth factors (FGFs) belong to the most important growth factors in melanoma, expression of FGF receptor subtype 4 has not been investigated yet. In this study, the protein expression of this receptor was analysed in 137 melanoma tissues of different progression stages by immunohistochemistry. FGFR4 protein was expressed in 45% of the specimens and correlated with pTNM tumour stages (UICC, P=0.023 and AJCC, P=0.046), presence of microulceration (P=0.009), tumour vascularity (P=0.001), metastases (P=0.025), number of primary tumours (P=0.022), overall survival (P=0.047) and disease-free survival (P=0.024). Furthermore, FGFR4 Arg388 polymorphism was analysed in 185 melanoma patients by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The Arg388 allele was detected in 45% of the melanoma patients and was significantly associated with tumour thickness (by Clark's level of invasion (P=0.004) and by Breslow in mm (P=0.02)) and the tumour subtype nodular melanoma (P=0.002). However, there was no correlation of the FGFR4 Arg388 allele with overall and disease-free survival. In conclusion, the Arg388 genotype and the protein expression of FGFR4 may be potential markers for progression of melanoma

Diversity in Functional Organization of Class I and Class II Biotin Protein Ligase

The cell envelope of Mycobacterium tuberculosis (M.tuberculosis) is composed of a variety of lipids including mycolic acids, sulpholipids, lipoarabinomannans, etc., which impart rigidity crucial for its survival and pathogenesis. Acyl CoA carboxylase (ACC) provides malonyl-CoA and methylmalonyl-CoA, committed precursors for fatty acid and essential for mycolic acid synthesis respectively. Biotin Protein Ligase (BPL/BirA) activates apo-biotin carboxyl carrier protein (BCCP) by biotinylating it to an active holo-BCCP. A minimal peptide (Schatz), an efficient substrate for Escherichia coli BirA, failed to serve as substrate for M. tuberculosis Biotin Protein Ligase (MtBPL). MtBPL specifically biotinylates homologous BCCP domain, MtBCCP87, but not EcBCCP87. This is a unique feature of MtBPL as EcBirA lacks such a stringent substrate specificity. This feature is also reflected in the lack of self/promiscuous biotinylation by MtBPL. The N-terminus/HTH domain of EcBirA has the self-biotinable lysine residue that is inhibited in the presence of Schatz peptide, a peptide designed to act as a universal acceptor for EcBirA. This suggests that when biotin is limiting, EcBirA preferentially catalyzes, biotinylation of BCCP over self-biotinylation. R118G mutant of EcBirA showed enhanced self and promiscuous biotinylation but its homologue, R69A MtBPL did not exhibit these properties. The catalytic domain of MtBPL was characterized further by limited proteolysis. Holo-MtBPL is protected from proteolysis by biotinyl-5′ AMP, an intermediate of MtBPL catalyzed reaction. In contrast, apo-MtBPL is completely digested by trypsin within 20 min of co-incubation. Substrate selectivity and inability to promote self biotinylation are exquisite features of MtBPL and are a consequence of the unique molecular mechanism of an enzyme adapted for the high turnover of fatty acid biosynthesis

Acetate supplementation modulates brain histone acetylation and decreases interleukin-1β expression in a rat model of neuroinflammation

<p>Abstract</p> <p>Background</p> <p>Long-term acetate supplementation reduces neuroglial activation and cholinergic cell loss in a rat model of lipopolysaccharide-induced neuroinflammation. Additionally, a single dose of glyceryl triacetate, used to induce acetate supplementation, increases histone H3 and H4 acetylation and inhibits histone deacetylase activity and histone deacetylase-2 expression in normal rat brain. Here, we propose that the therapeutic effect of acetate in reducing neuroglial activation is due to a reversal of lipopolysaccharide-induced changes in histone acetylation and pro-inflammatory cytokine expression.</p> <p>Methods</p> <p>In this study, we examined the effect of a 28-day-dosing regimen of glyceryl triacetate, to induce acetate supplementation, on brain histone acetylation and interleukin-1β expression in a rat model of lipopolysaccharide-induced neuroinflammation. The effect was analyzed using Western blot analysis, quantitative real-time polymerase chain reaction and enzymic histone deacetylase and histone acetyltransferase assays. Statistical analysis was performed using one-way analysis of variance, parametric or nonparametric when appropriate, followed by Tukey's or Dunn's post-hoc test, respectively.</p> <p>Results</p> <p>We found that long-term acetate supplementation increased the proportion of brain histone H3 acetylated at lysine 9 (H3K9), histone H4 acetylated at lysine 8 and histone H4 acetylated at lysine 16. However, unlike a single dose of glyceryl triacetate, long-term treatment increased histone acetyltransferase activity and had no effect on histone deacetylase activity, with variable effects on brain histone deacetylase class I and II expression. In agreement with this hypothesis, neuroinflammation reduced the proportion of brain H3K9 acetylation by 50%, which was effectively reversed with acetate supplementation. Further, in rats subjected to lipopolysaccharide-induced neuroinflammation, the pro-inflammatory cytokine interleukin-1β protein and mRNA levels were increased by 1.3- and 10-fold, respectively, and acetate supplementation reduced this expression to control levels.</p> <p>Conclusion</p> <p>Based on these results, we conclude that dietary acetate supplementation attenuates neuroglial activation by effectively reducing pro-inflammatory cytokine expression by a mechanism that may involve a distinct site-specific pattern of histone acetylation and histone deacetylase expression in the brain.</p

GM-CSF-Producing Th Cells in Rats Sensitive and Resistant to Experimental Autoimmune Encephalomyelitis

Given that granulocyte macrophage colony-stimulating factor (GM-CSF) is identified as the key factor to endow auto-reactive Th cells with the potential to induce neuroinflammation in experimental autoimmune encephalomyelitis (EAE) models, the frequency and phenotype of GM-CSF-producing (GM-CSF+) Th cells in draining lymph nodes (dLNs) and spinal cord (SC) of Albino Oxford (AO) and Dark Agouti (DA) rats immunized for EAE were examined. The generation of neuroantigen-specific GM-CSF+ Th lymphocytes was impaired in dLNs of AO rats (relatively resistant to EAE induction) compared with their DA counterparts (susceptible to EAE) reflecting impaired CD4+ lymphocyte proliferation and less supportive of GM-CSF+ Th cell differentiation dLN cytokine microenvironment. Immunophenotyping of GM-CSF+ Th cells showed their phenotypic heterogeneity in both strains and revealed lower frequency of IL-17+ IFN-gamma+, IL-17+ IFN-gamma-, and IL-17-IFN-gamma+ cells accompanied by higher frequency of IL-17-IFN-gamma- cells among them in AO than in DA rats. Compared with DA, in AO rats was also found (i) slightly lower surface density of CCR2 (drives accumulation of highly pathogenic GM-CSF+ IFN-gamma+ Th17 cells in SC) on GM-CSF+ IFN-gamma+ Th17 lymphocytes from dLNs, and (ii) diminished CCL2 mRNA expression in SC tissue, suggesting their impaired migration into the SC. Moreover, dLN and SC cytokine environments in AO rats were shown to be less supportive of GM-CSF+ IFN-gamma+ Th17 cell differentiation (judging by lower expression of mRNAs for IL-1 beta, IL-6 and IL-23/p19). In accordance with the (i) lower frequency of GM-CSF+ Th cells in dLNs and SC of AO rats and their lower GM-CSF production, and (ii) impaired CCL2 expression in the SC tissue, the proportion of proinflammatory monocytes among peripheral blood cells and their progeny (CD45(hi) cells) among the SC CD11b+ cells were reduced in AO compared with DA rats. Collectively, the results indicate that the strain specificities in efficacy of several mechanisms controlling (auto) reactive CD4+ lymphocyte expansion/differentiation into the cells with pathogenic phenotype and migration of the latter to the SC contribute to AO rat resistance to EAE

PDE 7 Inhibitors: New Potential Drugs for the Therapy of Spinal Cord Injury

BACKGROUND: Primary traumatic mechanical injury to the spinal cord (SCI) causes the death of a number of neurons that to date can neither be recovered nor regenerated. During the last years our group has been involved in the design, synthesis and evaluation of PDE7 inhibitors as new innovative drugs for several neurological disorders. Our working hypothesis is based on two different facts. Firstly, neuroinflammation is modulated by cAMP levels, thus the key role for phosphodiesterases (PDEs), which hydrolyze cAMP, is undoubtedly demonstrated. On the other hand, PDE7 is expressed simultaneously on leukocytes and on the brain, highlighting the potential crucial role of PDE7 as drug target for neuroinflammation. METHODOLOGY/PRINCIPAL FINDINGS: Here we present two chemically diverse families of PDE7 inhibitors, designed using computational techniques such as virtual screening and neuronal networks. We report their biological profile and their efficacy in an experimental SCI model induced by the application of vascular clips (force of 24 g) to the dura via a four-level T5-T8 laminectomy. We have selected two candidates, namely S14 and VP1.15, as PDE7 inhibitors. These compounds increase cAMP production both in macrophage and neuronal cell lines. Regarding drug-like properties, compounds were able to cross the blood brain barrier using parallel artificial membranes (PAMPA) methodology. SCI in mice resulted in severe trauma characterized by edema, neutrophil infiltration, and production of a range of inflammatory mediators, tissue damage, and apoptosis. Treatment of the mice with S14 and VP1.15, two PDE7 inhibitors, significantly reduced the degree of spinal cord inflammation, tissue injury (histological score), and TNF-α, IL-6, COX-2 and iNOS expression. CONCLUSIONS/SIGNIFICANCE: All these data together led us to propose PDE7 inhibitors, and specifically S14 and VP1.15, as potential drug candidates to be further studied for the treatment of SCI

Olprinone Attenuates the Acute Inflammatory Response and Apoptosis after Spinal Cord Trauma in Mice

BACKGROUND: Olprinone hydrochloride is a newly developed compound that selectively inhibits PDE type III and is characterized by several properties, including positive inotropic effects, peripheral vasodilatory effects, and a bronchodilator effect. In clinical settings, olprinone is commonly used to treat congestive cardiac failure, due to its inotropic and vasodilating effects. The mechanism of these cardiac effects is attributed to increased cellular concentrations of cAMP. The aim of the present study was to evaluate the pharmacological action of olprinone on the secondary damage in experimental spinal cord injury (SCI) in mice. METHODOLOGY/PRINCIPAL FINDINGS: Traumatic SCI is characterized by an immediate, irreversible loss of tissue at the lesion site, as well as a secondary expansion of tissue damage over time. Although secondary injury should be preventable, no effective treatment options currently exist for patients with SCI. Spinal cord trauma was induced in mice by the application of vascular clips (force of 24 g) to the dura via a four-level T5-T8 laminectomy. SCI in mice resulted in severe trauma characterized by edema, neutrophil infiltration, and production of inflammatory mediators, tissue damage, apoptosis, and locomotor disturbance. Olprinone treatment (0.2 mg/kg, i.p.) 1 and 6 h after the SCI significantly reduced: (1) the degree of spinal cord inflammation and tissue injury (histological score), (2) neutrophil infiltration (myeloperoxidase activity), (3) nitrotyrosine formation, (4) pro-inflammatory cytokines, (5) NF-kappaB expression, (6) p-ERK1/2 and p38 expression and (7) apoptosis (TUNEL staining, FAS ligand, Bax and Bcl-2 expression). Moreover, olprinone significantly ameliorated the recovery of hind-limb function (evaluated by motor recovery score). CONCLUSIONS/SIGNIFICANCE: Taken together, our results clearly demonstrate that olprinone treatment reduces the development of inflammation and tissue injury associated with spinal cord trauma

Die Rezeption Karl Barths und der dialektischen Theologie in der russischen Religionsphilosophie

akzeptierte Manuskriptversio

CNS Infiltration of Peripheral Immune Cells: D-Day for Neurodegenerative Disease?

While the central nervous system (CNS) was once thought to be excluded from surveillance by immune cells, a concept known as “immune privilege,” it is now clear that immune responses do occur in the CNS—giving rise to the field of neuroimmunology. These CNS immune responses can be driven by endogenous (glial) and/or exogenous (peripheral leukocyte) sources and can serve either productive or pathological roles. Recent evidence from mouse models supports the notion that infiltration of peripheral monocytes/macrophages limits progression of Alzheimer's disease pathology and militates against West Nile virus encephalitis. In addition, infiltrating T lymphocytes may help spare neuronal loss in models of amyotrophic lateral sclerosis. On the other hand, CNS leukocyte penetration drives experimental autoimmune encephalomyelitis (a mouse model for the human demyelinating disease multiple sclerosis) and may also be pathological in both Parkinson's disease and human immunodeficiency virus encephalitis. A critical understanding of the cellular and molecular mechanisms responsible for trafficking of immune cells from the periphery into the diseased CNS will be key to target these cells for therapeutic intervention in neurodegenerative diseases, thereby allowing neuroregenerative processes to ensue