Caries resistance of lased human enamel with Er : YAG laser - morphological and ratio Ca/P analysis

Objective: In vitro analysis of caries resistance of dental enamel under caries simulation after irradiation with Er:YAG laser. Background Data: More susceptible to caries development spots at adjacent hard tissues from cavity preparations of dental tissues using burrs or lasers are quite common. Methods: Thirteen caries-free third permanent human molars were distributed as follows: G1: sound control and caries control; G2: Er:YAG 100, 200, 300, or 400 mJ/ 10 Hz/ 3 sec.; G3: the same parameters of G2 followed by artificial caries simulation, through dynamic model of demineralization and remineralization (DE/RE). Caries resistance analysis was evaluated through scanning electron microscopy (SEM) and Ca/P rate (X-Rays spectroscopy - EDX). Results: Photomicrographs showed that the Er:YAG laser created craters with rough aspect which became more evident as the energy per pulse was increased, but without change of regular morphology of enamel prisms. Significant statistical changes among the irradiated and control groups was observed considering the Ca/P ratio. Conclusion: Irradiated groups showed higher caries resistance than control groups. However, it is not possible to affirm that the enamel surface accidental irradiation could be a benefit to caries resistance for other situations can be considered, as biofilm deposit, which could increase the caries susceptibility.

Pathogenicity of isolates of Metarhizium anisopliae (Metsch.) Sorokin towards the cattle tick Boophilus microplus (Can.) (Acari : Ixodidae) under laboratory conditions

The pathogenic activity of Metarhizium anisopliae on Boophilus microplus females was assessed using five fungal isolates. Groups of 8 engorged ticks collected from cattle on free pasture were inoculated by immersion for 5 seconds in a spore suspension containing 2.5 x 10(8) conidia/ml. The groups were transferred to moist chambers in which they were maintained at 27 +/- 1 degreesC for about 15 days, their mortality being determined every 2, or occasionally 3, days. The isolate that produced the best results in this assay was used to inoculate female ticks with spore suspensions containing 0, 7.5 x 105, 7.5 x 10(6), 7.5 x 10(7) and 7.5 x 10(8) conidia/ml, under the same conditions as described above. The pathogenic action of M. anisopliae on engorged females was clearly demonstrated. Isolates E9 and AM were more effective, causing high tick mortality as well as reduced oviposition. The concentration of 7.5 x 10(8) conidia/ml was the most effective, with the fungus sporulating on 91.1% of the ticks. Mean percent oviposition was highest in the control treatment and lowest in the treatment with 7.5 x 10(8) conidia/ml.

Actively transcribed GAL genes can be physically linked to the nuclear pore by the SAGA chromatin modifying complex

Recent work has demonstrated that some actively transcribed genes closely associate with nuclear pore complexes (NPC) at the nuclear periphery. The Saccharomyces cerevisiae Mlp1 and Mlp2 proteins are components of the inner nuclear basket of the nuclear pore that mediate interactions with these active genes. To investigate the physical link between the NPC and active loci, we identified proteins that interact with the carboxyl-terminal globular domain of Mlp1 by tandem affinity purification coupled with mass spectrometry. This analysis led to the identification of several components of the Spt-Ada-Gcn5-acetyltransferase ( SAGA) histone acetyltransferase complex, Gcn5, Ada2, and Spt7. We utilized co-immunoprecipitation and in vitro binding assays to confirm the interaction between the Mlp proteins and SAGA components. Chromatin immunoprecipitation experiments revealed that Mlp1 and SAGA components associate with the same region of the GAL promoters. Critically, this Mlp-promoter interaction depends on the integrity of the SAGA complex. These results identify a physical association between SAGA and the NPC, and support previous results that relied upon visualization of GAL loci at the nuclear periphery by microscopy ( Cabal, G. G. Genovesio, A., Rodriguez-Navarro, S., Zimmer, C., Gadal, O., Lesne, A., Buc, H., Feuerbach- Fournier, F., Olivo-Marin, J.-C., Hurt, E. C., and Nehrbass, U. ( 2006) Nature 441, 770-773). We propose that a physical interaction between nuclear pore components and the SAGA complex can link the actively transcribed GAL genes to the nuclear pore.

Cr3+ and Cr4+ luminescence in glass ceramic silica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Geochemical Assessment of a Subtropical Reservoir: A Case Study in Curitiba, Southern Brazil

Suspended particles and dissolved substances in water provide reactive surfaces, influence metabolic activity and contribute to the net sediment deposition. It therefore plays an important part in the ecology and quality of the water mass. The water quality in reservoirs is crucial and it is naturally maintained by flushing and sedimentation, which continuously remove phosphorus from the water. In some reservoirs, however, these removal processes are countered by recycling of ions which could play a key role to start and/or maintain the eutrophic state. The combination of macro-, trace- and microanalysis techniques can be useful to trace pollution sources through a chemical fingerprint, whether be during an acute environmental disaster or a long-term release of pollutants. The water quality and total metal content of reservoir sediments were assessed in a reservoir, situated in the capital of the Parana State, in the South-Eastern part of Brazil. The goal of this paper was to determine the metal presence in the sediment and metal and ionic speciation in the Green River reservoir water. Water and bed sediment samples, collected from various sites during 2008 and 2009, were investigated using XRF, ICP-OES, ICP-MS, XRD and zeta potential measurements. Based on the results, the heavy metal concentration and chemical composition of the suspended matter in the water samples, as well as the sediment's chemical composition will be discussed.

Prevention of social stress-escalated cocaine self-administration by CRF-R1 antagonist in the rat VTA

Intermittent exposure to social defeat stress can induce long-term neural plasticity that may influence escalated cocaine-taking behavior. Stressful encounters can lead to activation of dopamine neurons in the ventral tegmental area (VTA), which are modulated by corticotropin releasing factor (CRF) neurons.The study aims to prevent the effects of intermittently scheduled, brief social defeat stress on subsequent intravenous (IV) cocaine self-administration by pretreatment with a CRF receptor subtype 1 (CRF-R1) antagonist.Long-Evans rats were submitted to four intermittent social defeat experiences separated by 72 h over 10 days. Two experiments examined systemic or intra-VTA antagonism of CRF-R1 subtype during stress on the later expression of locomotor sensitization and cocaine self-administration during fixed (0.75 mg/kg/infusion) and progressive ratio schedules of reinforcement (0.3 mg/kg/infusion), including a continuous 24-h "binge" (0.3 mg/kg/infusion).Pretreatment with a CRF-R1 antagonist, CP 154,526, (20 mg/kg i.p.) prior to each social defeat episode prevented the development of stress-induced locomotor sensitization to a cocaine challenge and prevented escalated cocaine self-administration during a 24-h "binge". In addition, pretreatment with a CRF-R1 antagonist (0.3 mu g/0.5 mu l/side) into the VTA prior to each social defeat episode prevented stress-induced locomotor sensitization to a cocaine challenge and prevented escalated cocaine self-administration during a 24-h "binge".The current results suggest that CRF-R1 subtype in the VTA is critically involved in the development of stress-induced locomotor sensitization which may contribute to escalated cocaine self-administration during continuous access in a 24-h "binge".

Niobium to alcohol mol ratio control of the concurring esterification and etherification reactions promoted by NbCl5 and Al2O3 catalysts under microwave irradiation

Alcohols and acids can be switched to produce ethers or esters by varying the alcohol to catalyst mol ratio, in a new etherification and esterification method using NbCl5/Al2O3 catalyst under "solvent free" conditions and promoted by MW (microwave) irradiation. A "two sites" mechanism for the reaction is proposed, in an attempt to clarify the tendency of the catalyst to be dependent on the alcohol alone during the esterification process. (c) 2008 Elsevier B.V. All rights reserved.

Inhibitory effect of PGE(2) on the killing of Paracoccidioides brasiliensis by human monocytes can be reversed by cellular activation with cytokines

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Transcriptome architecture across tissues in the pig

Background: Artificial selection has resulted in animal breeds with extreme phenotypes. As an organism is made up of many different tissues and organs, each with its own genetic programme, it is pertinent to ask: How relevant is tissue in terms of total transcriptome variability? Which are the genes most distinctly expressed between tissues? Does breed or sex equally affect the transcriptome across tissues?Results: In order to gain insight on these issues, we conducted microarray expression profiling of 16 different tissues from four animals of two extreme pig breeds, Large White and Iberian, two males and two females. Mixed model analysis and neighbor - joining trees showed that tissues with similar developmental origin clustered closer than those with different embryonic origins. Often a sound biological interpretation was possible for overrepresented gene ontology categories within differentially expressed genes between groups of tissues. For instance, an excess of nervous system or muscle development genes were found among tissues of ectoderm or mesoderm origins, respectively. Tissue accounted for similar to 11 times more variability than sex or breed. Nevertheless, we were able to confidently identify genes with differential expression across tissues between breeds (33 genes) and between sexes (19 genes). The genes primarily affected by sex were overall different than those affected by breed or tissue. Interaction with tissue can be important for differentially expressed genes between breeds but not so much for genes whose expression differ between sexes.Conclusion: Embryonic development leaves an enduring footprint on the transcriptome. The interaction in gene x tissue for differentially expressed genes between breeds suggests that animal breeding has targeted differentially each tissue's transcriptome.

The variance of the index (R) of aggregation of Clark and Evans

The exact formula for the variance of the Index (R) of aggregation of Clark and Evans is derived. Due to the fact that R is a dimensionless number, its variance is independent of population density, being only a function of the sample size and so can be manipulated. © 1985 Springer-Verlag.