RESUMEN
Amygdala-prefrontal cortex (PFC) functional impairments have been linked to emotion dysregulation and aggression in borderline personality disorder (BPD). Fatty acid amide hydrolase (FAAH), the major catabolic enzyme for the endocannabinoid anandamide, has been proposed as a key regulator of the amygdala-PFC circuit that subserves emotion regulation. We tested the hypothesis that FAAH levels measured with [11C]CURB positron emission tomography in amygdala and PFC would be elevated in BPD and would relate to hostility and aggression. Twenty BPD patients and 20 healthy controls underwent FAAH genotyping (rs324420) and scanning with [11C]CURB. BPD patients were medication-free and were not experiencing a current major depressive episode. Regional differences in [11C]CURB binding were assessed using multivariate analysis of covariance with PFC and amygdala [11C]CURB binding as dependent variables, diagnosis as a fixed factor, and sex and genotype as covariates. [11C]CURB binding was marginally elevated across the PFC and amygdala in BPD (p = 0.08). In a priori selected PFC, but not amygdala, [11C]CURB binding was significantly higher in BPD (11.0%, p = 0.035 versus 10.6%, p = 0.29). PFC and amygdala [11C]CURB binding was positively correlated with measures of hostility in BPD (r > 0.4; p < 0.04). This study is the first to provide preliminary evidence of elevated PFC FAAH binding in any psychiatric condition. Findings are consistent with the model that lower endocannabinoid tone could perturb PFC circuitry that regulates emotion and aggression. Replication of these findings could encourage testing of FAAH inhibitors as innovative treatments for BPD.
Asunto(s)
Trastorno de Personalidad Limítrofe , Trastorno Depresivo Mayor , Amidohidrolasas , Trastorno de Personalidad Limítrofe/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones , Corteza Prefrontal/diagnóstico por imagenRESUMEN
The development of technologies for unconventional hydrocarbon exploration requires designing procedures to manage drilling waste that are consistent with the waste management hierarchy. In view of this, the possibility to apply shale drill cuttings as a prospective additive (replacing bentonite) to fly ash used for the production of lightweight aggregates (LWAs) was investigated. Moreover, a facile, waste-free method of LWAs production with using shales was proposed. Cuttings were characterized in terms of their mineralogical and elemental composition (XRD and XRF) as well as thermophysical behavior (TG-DTA and fusibility test). The sintered product, in turn, was assessed taking into account its structure, physicochemical and mechanical properties. It was found that the composition of the shale drill cuttings meets the conditions required for the bloating (as expressed by the SiO2/ΣFlux and Al2O3/SiO2 ratios) and binding processes (Al2O3 content), essential for the aggregates production. In comparison to bentonite, shales provided an additional source of kaolinite, which thermal transformation to mullite is crucial for the formation of mechanically durable structure of the aggregate. Moreover, the bulk density of the sintered product was found to be less than 1200â¯kg/m3, and the dry particle density below 2000â¯kg/m3, confirming that the obtained porous material belong to lightweight aggregates with accordance to European standard (UNE-EN-13055-1). The porosity of LWA was found to be higher (even up to 50%), thus the apparent density lower, compared with the reference product containing bentonite. These properties were accompanied by the relatively high crushing resistance which was up to 4.4â¯N/mm2. Hereby, usefulness of shale drill cuttings for LWAs production was confirmed.
Asunto(s)
Dióxido de Silicio , Administración de Residuos , Bentonita , Ceniza del Carbón , Estudios ProspectivosRESUMEN
With a polyclonal antibody raised against calreticulin (CRT) the locations where the protein occurs in unpollinated and pollinated styles of Petunia hybrida were localized. The epitopes binding the CRT antibody were immunolocalized preferentially in pollen tubes. In transmitting tract cells, both before and after pollination, the level of CRT was low. The protein was mainly localized in the cytosol and around dictyosomes of transmitting-tract cells. In pollen tubes, a high level of CRT was found at their tips rich in endoplasmatic reticulum, cisternae piles of reticular and/or dictyosomal origin, and vesicles. Binding sites of the CRT antibody were also found in the internal callosic cell wall of the pollen tube. These results indicate a role of CRT in cells directly participating in pollen-pistil interaction.
Asunto(s)
Proteínas de Unión al Calcio/análisis , Proteínas de Unión al Calcio/inmunología , Inmunohistoquímica/métodos , Magnoliopsida/anatomía & histología , Magnoliopsida/química , Proteínas de Plantas/análisis , Proteínas de Plantas/inmunología , Polen/química , Ribonucleoproteínas/análisis , Ribonucleoproteínas/inmunología , Anticuerpos/inmunología , Western Blotting , Proteínas de Unión al Calcio/química , Calreticulina , Epítopos/inmunología , Magnoliopsida/inmunología , Magnoliopsida/ultraestructura , Microscopía Electrónica , Proteínas de Plantas/química , Polen/inmunología , Polen/ultraestructura , Ribonucleoproteínas/químicaRESUMEN
Modification of B. subtilis EF-Tu by N-tosyl-L-phenylalanyl chloromethane destroyed its ability to promote protein synthesis and resulted in selective dissociation of the two binding activities of the protein for aminoacyl-tRNA. The modified EF-Tu was completely ineffective in the protection of the 3'-terminal CCA structure of tRNA against pancreatic ribonuclease, while remaining almost fully active in the protection of the ester bond between the 3'-terminal adenosine and the amino acid residue in aminoacyl-tRNA.
Asunto(s)
Clorometilcetonas de Aminoácidos/farmacología , Bacillus subtilis/análisis , Factor Tu de Elongación Peptídica/metabolismo , ARN de Transferencia Aminoácido-Específico/metabolismo , ARN de Transferencia de Fenilalanina/metabolismo , Clorometilcetona de Tosilfenilalanila/farmacología , Escherichia coli/análisis , Geobacillus stearothermophilus/análisisRESUMEN
Elongation factor EF-Tu (Mr approximately equal to 50 000) and elongation factor EF-G (Mr approximately equal to 78 000) were isolated from Bacillus stearothermophilus in a homogeneous form. The ability of EF-Tu to participate in protein synthesis is rapidly inactivated by N-tosyl-L-phenyl-alanylchloromethane (Tos-PheCH2Cl). EF-Tu X GTP is more susceptible to the inhibition by Tos-PheCH2Cl than is EF-Tu X GDP. Tos-PheCH2Cl forms a covalent equimolar complex with the factor by reacting with a cysteine residue in its molecule. The labelling of EF-Tu by the reagent irreversibly destroys its ability to bind aminoacyl-tRNA, which in turn protects the protein from this inactivation. This indicates that the modification of EF-Tu by Tos-PheCH2Cl occurs at the aminoacyl-tRNA binding site of the protein. To identify and characterize the site of aminoacyl-tRNA binding in EF-Tu, the factor was labelled with [14C]Tos-PheCH2Cl, digested with trypsin, the resulting peptides were separated by high-performance liquid chromatography and the sequence of the radioactive peptide was determined. The peptide has identical structure with an Escherichia coli EF-Tu tryptic peptide comprising the residues 75-89 and the Tos-PheCH2Cl-reactive cysteine at position 81 [Jonák, J., Petersen, T. E., Clark, B. F. C. and Rychlík, I. (1982) FEBS Lett. 150, 485-488]. Experiments on photo-oxidation of EF-Tu by visible light in the presence of rose bengal dye showed that there are apparently two histidine residues in elongation factor Tu from B. stearothermophilus which are essential for the interaction with aminoacyl-tRNA. This is clearly reminiscent of a similar situation in E. coli EF-Tu [Jonák, J., Petersen, T. E., Meloun, B. and Rychlík, I. (1984) Eur. J. Biochem. 144, 295-303]. Our results provide further evidence for the conserved nature of the site of aminoacyl-tRNA binding in elongation factor EF-Tu and show that Tos-PheCH2Cl reagent might be a favourable tool for the identification of the site in the structure of prokaryotic EF-Tus.