Metallic gold slows disease progression, reduces cell death and induces astrogliosis while simultaneously increasing stem cell responses in an EAE rat model of multiple sclerosis

Multiple sclerosis (MS) is the most common neurodegenerative disease in the Western world affecting younger, otherwise healthy individuals. Today no curative treatment exists. Patients suffer from recurring attacks caused by demyelination and underlying neuroinflammation, ultimately leading to loss of neurons. Recent research shows that bio-liberation of gold ions from metallic gold implants can ameliorate inflammation, reduce apoptosis and promote proliferation of neuronal stem cells (NSCs) in a mouse model of focal brain injury. Based on these findings, the present study investigates whether metallic gold implants affect the clinical signs of disease progression and the pathological findings in experimental autoimmune encephalomyelitis (EAE), a rodent model of MS. Gold particles 20–45?μm suspended in hyaluronic acid were bilaterally injected into the lateral ventricles (LV) of young Lewis rats prior to EAE induction. Comparing gold-treated animals to untreated and vehicle-treated ones, a statistically significant slowing of disease progression in terms of reduced weight loss was seen. Despite massive inflammatory infiltration, terminal deoxynucleotidyl transferase dUTP nick end labeling staining revealed reduced apoptotic cell death in disease foci in the brain stem of gold-treated animals, alongside an up-regulation of glial fibrillary acidic protein-positive reactive astrocytes near the LV and in the brain stem. Cell counting of frizzled-9 and nestin-stained cells showed statistically significant up-regulation of NSCs migrating from the subventricular zone. Additionally, the neuroprotective proteins Metallothionein-1 and -2 were up-regulated in the corpus callosum. In conclusion, this study is the first to show that the presence of small gold implants affect disease progression in a rat model of MS, increasing the neurogenic response and reducing the loss of cells in disease foci. Gold implants might thus improve clinical outcome for MS patients and further research into the long-term effects of such localized gold treatment is warranted.     

Design and synthesis of novel p38α MAP kinase inhibitors: discovery of pyrazole-benzyl ureas bearing 2-molpholinopyrimidine moiety

The discovery that pyrazole-benzyl urea derivatives bearing a 2-molpholinopyrimidine moiety are novel p38α inhibitors is described. A comparative view of the binding modes of SB-203580 and BIRB-796 by structural alignment of two X-ray co-crystal structures was utilized to identify this novel series. Modification of the benzyl group led to compound 2b, a highly potent p38α inhibitor. In in vivo studies, 2b inhibited the production of tumor necrosis factor-alpha in lipopolysaccharide-treated mouse in a dose-dependent manner. Furthermore, the results of a 5-day repeated oral dose toxicity study suggest that 2b has low hepatotoxicity.     

Evaluation of Vickers hardness of different types of acrylic denture base resins with and without glass fibre reinforcement

doi: 10.1111/j.1741‐2358.2010.00435.x
Evaluation of Vickers hardness of different types of acrylic denture base resins with and without glass fibre reinforcement Objective: To evaluate the Vickers hardness of different acrylic resins for denture bases with and without the addition of glass fibres. Background: It has been suggested that different polymerisation methods, as well as the addition of glass fibre (FV) might improve the hardness of acrylic. Materials and methods: Five types of acrylic resin were tested: Vipi Wave (VW), microwave polymerisation; Vipi Flash (VF), auto‐polymerisation; Lucitone (LT), QC20 (QC) and Vipi Cril (VC), conventional heat‐polymerisation, all with or without glass fibre reinforcement (GFR) and distributed into 10 groups (n = 12). Specimens were then submitted to Vickers hardness testing with a 25‐g load for 30 s. All data were submitted to anova and Tukey’s HSD test. Results: A significant statistical difference was observed with regard to the polymerisation method and the GFR (p < 0.05). Without the GFR, the acrylic resin VC presented the highest hardness values, and VF and LT presented the lowest. In the presence of GFR, VC resin still presented the highest Vickers hardness values, and VF and QC presented the lowest. Conclusions: The acrylic resin VC and VW presented higher hardness values than VF and QC resins. Moreover, GFR increased the Vickers hardness of resins VW, VC and LT.     

Reactions of Lotus japonicus ecotypes and mutants to root parasitic plants

Witchweeds (Striga spp.) and broomrapes (Orobanche spp.) are obligate root parasitic plants on economically important field and horticultural crops. The parasites' seeds are induced to germinate by root-derived chemical signals. The radicular end is transformed into a haustorium which attaches, penetrates the host root and establishes connection with the vascular system of the host. Reactions of Lotus japonicus, a model legume for functional genomics, were studied for furthering the understanding of host-parasite interactions. Lotus japonicus was compatible with Orobanche aegyptiaca, but not with Orobanche minor, Striga hermonthica and Striga gesnerioides. Orobanche minor successfully penetrated Lotus japonicus roots, but failed to establish connections with the vascular system. Haustoria in Striga hermonthica attached to the roots, but penetration and subsequent growth of the endophyte in the cortex were restricted. Striga gesnerioides did not parasitize Lotus japonicus. Among seven mutants of Lotus japonicus (castor-5, har1-5, alb1-1, ccamk-3, nup85-3, nfr1-3 and nsp2-1) with altered characteristics in relation to rhizobial nodulation and mycorrhizal colonization, castor-5 and har1-5 were parasitized by Orobanche aegyptiaca with higher frequency than the wild type. In contrast, Orobanche aegyptiaca tubercle development was delayed on the mutants nup85-3, nfr1-3 and nsp2-1. These results suggest that nodulation, mycorrhizal colonization and infection by root parasitic plants in Lotus japonicus may be modulated by similar mechanisms and that Lotus japonicus is a potential model legume for studying plant-plant parasitism.     

Malachite green induces cardiovascular defects in developing zebrafish (Danio rerio) embryos by blocking VEGFR-2 signaling

Malachite green (MG) is a triphenyl methane dye used in various fields that demonstrates high toxicity to bacteria and mammalian cells. When bud stage zebrafish embryos were treated with MG at 125, 150, and 175 ppb for 14 h, the development of trunk including intersomitic vessels was inhibited in MG-treated flk-1-GFP transgenic embyos. MG clearly induced whole growth retardation. MG induced severe cell death in trunk intersomite region of zebrafish embryos and in human vascular endothelial cells in a dose-dependent manner. MG inhibited heart rates and cardiac looping. MG attenuated whole blood formation and inhibited vascular endothelial growth factor (VEGF)-induced receptor (R)-2 phosphorylation in vascular endothelial cells. In conclusion, MG significantly alters the cardiovascular development causing growth retardation in zebrafish through the blocking VEGFR-2 activation in early cardiovascular development. It suggests that MG may be an environmental toxic agent with the potential to induce embryonic cardiovascular defects in vertebrates.     

Flexibility contra Stiffness: The Phragmoplast as a Physical Barrier for Beads But Not for Vesicles

In plant cells, Golgi vesicles are transported to the division plane to fuse with each other, forming the cell plate, the initial membrane-bordered cell wall separating daughter cells. Vesicles, but not organelles, move through the phragmoplast, which consists of two opposing cylinders of microtubules and actin filaments, interlaced with endoplasmic reticulum membrane. To study physical aspects of this transport/inhibition process, we microinjected fluorescent synthetic 1,2-dioleoyl-sn-glycero-3-phospho-rac-1-glycerol (DOPG) vesicles and polystyrene beads into Tradescantia virginiana stamen hair cells. The phragmoplast was nonselective for DOPG vesicles of a size up to 150 nm in diameter but was a physical barrier for polystyrene beads having a diameter of 20 and 40 nm and also when beads were coated with the same DOPG membrane. We conclude that stiffness is a parameter for vesicle transit through the phragmoplast and discuss that cytoskeleton configurations can physically block such transit.Cells and their constituents are physical entities, and next to chemical interactions, cell structures are determinants of cell behavior. Therefore, apart from techniques to image living cells at the subcellular level, experiments are needed that probe physical parameters important in cell function in vivo. We took the plant phragmoplast structure to answer the question whether the physical aspect “stiffness” is a factor in the inhibition of transport through this structure by microinjecting synthetic vesicles and polystyrene beads in Tradescantia virginiana stamen hair cells during cytokinesis, when the phragmoplast is essential for partitioning the cytoplasm between two daughter cells. Plant cells partition by producing a cell plate made of fused 60- to 80-nm-diameter vesicles (Staehelin and Hepler, 1996; Jürgens, 2005) proven to be Golgi vesicles (Reichardt et al., 2007). Their content becomes the new cell wall and their membranes become the daughter cell plasma membranes. The phragmoplast consists of two opposing cylinders of microtubules and actin filaments, interlaced with similarly aligned endoplasmic reticulum (ER) membranes. This phragmoplast cytoskeleton is the transport vehicle for Golgi vesicles to the plane where the cell plate is being formed (Staehelin and Hepler, 1996; Valster et al., 1997), keeps them in this plane (Esseling-Ozdoba et al., 2008b), where they fuse with each other (Samuels et al., 1995; Otegui et al., 2001; Seguí-Simarro et al., 2004), and assists in the proper attachment of the cell plate to the parental cell wall (Valster et al., 1997; Molchan et al., 2002). Transit of organelles, including Golgi bodies, is inhibited (Staehelin and Hepler, 1996; Nebenführ et al., 2000; Seguí-Simarro et al., 2004). Most of these data are known from static electron microscopy images. Electron microscopy after high-pressure freezing and freeze substitution (Thijsen et al., 1998) and electron tomography studies (Otegui et al., 2001; Seguí-Simarro et al., 2004; Austin et al., 2005) show that, in the early stage of cell plate formation in the center and later at the phragmoplast border, microtubules are aligned parallel to each other at distances of 20 to 100 nm. Keeping in mind that also actin filaments and ER membranes, aligned in the same orientation, are present between the microtubules, this leaves little room for the cell plate-forming vesicles during their transport through this phragmoplast.Clearly, during the past decade, significant progress has been made in the elucidation of the structural organization of cell plate-forming phragmoplasts, which has set the stage for studies to elucidate physical properties of phragmoplasts. The experimental approach we use is injecting particulate and vesicular fluorescent probes into living and dividing cells and observing the extent to which such probes can enter the phragmoplast and can be transported to the cell plate region. We have shown before that synthetic lipid 1,2-dioleoyl-sn-glycero-3-phospho-rac-1-glycerol (DOPG) vesicles of 60 nm diameter are transported through the phragmoplast, accumulate, and are kept in the cell plate region but do not fuse (Esseling-Ozdoba et al., 2008b). Now, we asked whether similar, flexible, synthetic lipid (DOPG) vesicles of various sizes, smaller and larger than endogenous vesicles, as well as stiff polystyrene beads, and such beads coated with the DOPG membrane, are transported through the phragmoplast and enter the plane where the cell plate is being formed, a question pertaining to a physical property of the phragmoplast. Our principal finding is that injected synthetic vesicles up to 150 nm diameter can enter and be transported to the cell plate region, where they accumulate but do not become incorporated into the cell plate. In contrast, polystyrene beads, the noncoated ones and those coated with the same lipid as the vesicles with diameters of 20 and 40 nm, can enter phragmoplasts but cannot be transported to the cell plate region, and the 40-nm beads slow cell plate formation, possibly by interfering with the delivery of normal, cell plate-forming vesicles to the cell plate.     

Heterologous expression of the AtDREB1A gene in chrysanthemum increases drought and salt stress tolerance

DNA cassette containing an AtDREB1A cDNA and a nos terminator,driven by a cauli- flower mosaic 35S promoter,or a stress-inducible rd29A promoter,was transformed into the ground cover chrysanthemum(Dendranthema grandiflorum)'Fall Color'genome.Compared with wild type plants,severe growth retardation was observed in 35S:DREB1A plants,but not in rd29A:DREB1A plants.RT-PCR analysis revealed that,under stress conditions,the DREB1A gene was over-expressed constitutively in 35S:DREB1A plants,but was over-expressed inductively in rd29A:DREB1A plants.The transgenic plants exhibited tolerance to drought and salt stress,and the tolerance was significantly stronger in rd29A:DREB1A plants than in 35S:DREB1A plants.Proline content and SOD activity were increased inductively in rd29A:DREB1A plants than in 35S:DREB1A plants under stress conditions.These results indicate that heterologous AtDREB1A can confer drought and salt tolerance in transgenic chrysanthemum,and improvement of the stress tolerance may be related to enhancement of proline content and SOD activity.     

Mandibular symphysis dimensions in different sagittal and vertical skeletal relationships

BackgroundThe aim of this cross-sectional study was to compare the dimensions of mandibular symphysis (MS) between gender and the different sagittal and vertical skeletal relationships.Material and MethodsPre-treatment records of orthodontic patients were divided according to gender, sagittal (Class I, II and III) and vertical (decreased, average and increased mandibular plane [MP] angle) skeletal relationships. Measurements of MS parameters were performed on lateral cephalograms using IMAGEJ software. Comparisons between MS parameters and gender and the different skeletal relationships was performed using multifactorial and one-way ANOVA, and independent sample t-tests.ResultsA total of 104 records (25 males and 79 females) fulfilled the inclusion criteria. Males had significantly greater MS surface area, dentoalveolar length, skeletal symphysis length, total symphysis length, vertical symphysis dimension and symphysis convexity (p < 0.05). Skeletal Class II patients had significantly greater dentoalveolar and skeletal symphysis lengths while Class III had greater chin length, vertical symphysis dimension and symphysis convexity (p < 0.05). Patients with decreased vertical dimension had greater skeletal symphysis length (p = 0.026) and those with an average vertical relationship had greater chin length (p < 0.001).ConclusionsThe morphology of the mandibular symphysis is affected by gender, sagittal and vertical skeletal patterns. Males had increased mandibular symphysis surface area and linear dimensions. Class II patients had greater dentoalveolar length. Chin length was greater in patients with an average MP angle.     

Winding threads around plant cells Applications of the geometrical model for microfibril deposition

Summary Based on precise information about the orientations of cellulose microfibrils (CMFs) in the secondary cell wall of theEquisetum hyemale root hair, a geometrical model was recently put forward to account for the deposition orientation of CMFs. The model supposes that synthases spin out the CMFs and that geometrical laws dictate their movement. Taking space-limiting conditions into account, CMF orientation is dependent on cell morphology, the amount of other wall molecules adhering to the CMFs, and the number and distribution pattern of synthases. In the present paper this geometrical model for CMF deposition is further applied to nontip-growing angular cells with varying diameters, cells with tapering morphology, various distribution patterns of synthases, various matrix/fibril ratios, and intercalarily elongating cells. The model can accurately predict the actual wall textures in a great variety of cell walls. In the proposed model for CMF orientation, microtubules are not required as cellular guiding structures for the CMFs, not even in elongating walls. They are supposed to be involved in cell elongation, possibly by delivering wall material including CMF synthases.Abbreviation CMF cellulose microfibril