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Introduction: Glioblastoma multiforme (GBM) is the most lethal form of gliomas. New therapies are currently in development to tackle treatment limitations such as chemotherapy resistance. One mechanism of resistance may be the stress granules (SG) assembly, a stress-related cellular response that allows cells to recruit and protect mRNAs during stress. SG are composed of various proteins, being G3BP1 a core element that enucleates and results in SG assembly. Here, we aimed to evaluate the effects of inhibiting the G3PB1 expression in the chemotherapeutical-induced cell death of the U87 glioblastoma cell line. Materials and Methods: G3BP1 mRNA and protein expression were modulated with short-interference RNA (siRNA). The viability of U87 cells after Bortezomib (BZM), a proteasome inhibitor, and Temozolomide (TMZ), an alkylating agent, was assessed by MTT assay. Apoptosis was evaluated by staining cells with Annexin-V/7-AAD and analyzing by flow cytometry. Caspase-3 activation was evaluated by immunoblotting. The chorioallantoic membrane in vivo assay was used to evaluate angiogenesis. Results: When G3BP1 was knocked-down, the SG assembly was reduced and the BZM-treated cells, but not TMZ-treated cells, had a significant increase in the apoptotic response. Corroborating this data, we observed increased Caspase-3 activation in the BZM-treated and G3BP1-knocked-down cells when compared to vehicle-treated and scramble-transfected cells. Worth mentioning, the conditioned culture medium of G3BP1-knocked-down BZM-treated cells inhibited angiogenesis when compared to controls. Conclusion: Our data suggest G3BP1 knockdown diminishes SG formation and stimulates BZM-induced apoptosis of U87 cells in vitro, in addition to inhibiting glioblastoma-induced angiogenesis in vivo. [ABSTRACT FROM AUTHOR]

In this paper, a numerical and an experimental approach are established to study the influence of the machining parameters on the resonance frequency shift of ultrasonic assisted turning. The numerical model incorporates the mechanical and electrical effect on the simulation mode shape and resonance frequency of entire ultrasonic equipment. It is numerically shown that the machining parameters' variability promotes a resonance frequency shifting, and the depth of cut is suggested to have more effect than the feed rate. Experimental results demonstrated that for the same cutting speed and different depth of cut and feed, the frequency value shifts thus compromise the surface quality. With the frequency adjustment promoted by MMM system, surface roughness improves 10 and 14%, when the feed is increased from 0.045 to 0.18 mm/rev, respectively, for a depth of cut of 1.5 mm. [ABSTRACT FROM AUTHOR]

Clavibacter michiganensis subsp. michiganensis can cause severe losses to tomato crops and new types of alternative control must be identified. Induced resistance is a potential method. Among resistance inducers, the mushrooms Lentinula edodes (Le) and Agaricus subrufescens (Abl) exhibit the potential to be used in plant disease control. The objectives of this study were: (i) evaluate the potential of these mushrooms and of acibenzolar-S-methyl (aSm) to control bacterial canker; (ii) study the mode of action of these materials by measuring defense-relate enzyme activity; (iii) partially purify biologically active molecules. The aqueous extracts from mushroom isolates, as well as aSm, did not inhibit bacterial growth in vitro. However, 10% (v/v) solutions of extracts from the isolates Le-96/17 and Abl-26, as well as aSm, reduced wilt in tomato plants under greenhouse conditions. Plants treated with aSm, Abl-26 and Le-96/17 showed an increase in peroxidase and chitinase. Phenylalanine ammonia-lyase (PAL) and polyphenol oxidase (PPO) activities increased with all treatments. Because isolate Le-96/17 induced the greatest wilt reduction, its aqueous extract was precipitated with ammonium sulfate. The fraction at 40-80% saturation was submitted to anion-exchange chromatography (AEC). The AEC fractions 3 and 4, the inducer aSm and the aqueous extract of Le-96/17 reduced the bacterial disease. The fractions 3 and 4, the 40-80% precipitate and the aqueous extract from Le-96/17 contained more than one protein band. In conclusion, the isolate Le-96/17 induced resistance to C. michiganensis in tomato and partial purification of the inducer molecules was obtained. [ABSTRACT FROM AUTHOR]

Unconjugated bilirubin (UCB) injury to glial cells leads to the secretion of glutamate and elicits a typical inflammatory response. Release of pro-inflammatory cytokines may influence gliogenesis and neurogenesis, and lead to deficits in learning and memory. Glutamate metabolism dysregulation and overexpression of tumor necrosis factor-α (TNF-α) and interleukin (IL)-1β are consistent with schizophrenia neuropathology. Recently, an increased prevalence of schizophrenia was reported in individuals with Gilbert's syndrome and among those who have had elevated levels of UCB in the neonatal life. In this review, we explore the reactivity of astrocytes, neurons and microglia to UCB, the cascade of events implicated in the immunostimulant effects of UCB, as well as the role of each nerve cell type and maturation state in the neuropathology of UCB. Identification of the signaling events promoted by UCB will be relevant for developing novel therapies that might reduce the risk of brain injury and disabilities.Journal of Perinatology (2009) 29, S8–S13; doi:10.1038/jp.2008.214 [ABSTRACT FROM AUTHOR]

Comparative genomic studies of attenuated and virulent strains of Gallid herpesvirus 2 (GaHV-2) have identified 6 regions of sequence variability. These regions include the open reading frames (ORFs) encoding UL36 and UL49 and regions devoid of large ORFs (132-bp repeats, a-like sequences and the junctions flanking the unique short region). Our data indicate that the carboxyl terminus of UL36 contains regions of heterogeneity that are unique to CVI988-derived attenuated strains. A deletion of the TKSERT domain and a glycine245 polymorphism in the UL49 proteins were also identified in these derivatives. Phylogenetic analyses of both UL36 and UL49 sequences indicate that CVI988-derived strains partition differently from other attenuated strains (RM-1 and R2/23), indicating that additional mutations contribute to attenuation. In very virulent and very virulent plus strains a single nucleotide polymorphism (SNP) was identified within the 132-bp tandem repeats. Within the junctions flanking the unique short region, these strains also contain deletions in sequences that are predicted to bind the transcription factor NF kappaB. In some attenuated strains, deletions were also identified in the latency-associated transcript (LAT) promoters and adjacent regions encoding microRNAs. These results indicate that virulence is likely multi-factorial with contributions from both multiple genes and cis-acting sites. [ABSTRACT FROM AUTHOR]

In the initial online version of the article, author F.M. Soriani was missing. The original article has been corrected. [ABSTRACT FROM AUTHOR]