The effect of dexamethasone treatment on the expression of the regulatory genes of ketogenesis in intestine and liver of suckling rats

The influence of the injection of dexamethasone on ketogenesis in 12 day old suckling rats was studied in intestine and liver by determining mRNA levels and enzyme activity of the two genes responsible for regulation of ketogenesis: carnitine palmitoyl transferase I (CPT I) and mitochondrial HMG-CoA synthase. Dexamethasone produced a 2 fold increase in mRNA and activity of CPT I in intestine, but led to a decrease in mit. HMG-CoA synthase. In liver the mRNA levels and activity of both CPT I and mit. HMG-CoA synthase decreased. Comparison of these values with the ketogenic rate of both tissues following dexamethasone treatment suggests that mit. HMG-CoA synthase could be the main gene responsible for the regulation of ketogenesis in suckling rats. The changes produced in serum ketone bodies by dexamethasone, with a profile that is more similar to the ketogenic rate in the liver than that in the intestine, indicate that liver contributes more to ketone body synthesis in suckling rats. Two day treatment with dexamethasone produced no change in mRNA or activity levels for CPT I in liver or intestine. While mRNA levels for mit. HMG-CoA synthase changed little, the enzyme activity is decreased in both tissues.     

Polyphasic characterization of indigenous lactobacilli and lactococci from PDO Canestrato Pugliese cheese

A polyphasic approach, involving both genotypic and phenotypic analyses was used to characterize 33 isolates of lactic acid bacteria from the raw milk Protected Designation of Origin (PDO) Canestrato Pugliese cheese, in order to select candidate strains that can be used as autochthonous starter cultures in the dairy industry. Randomly amplified polymorphic DNA (RAPD) analysis and clustering by the unweighted pair-group method with arithmetic averages (UPGMA) were used to evaluate the genotypic diversity, while phenotypic characterization was performed through miniaturized assays and traditional biochemical tests. Technological properties of major interest for cheese-making (acidification, tendency to lysis, proteolytic and peptidase activity) were also evaluated, and selected subset of data was statistically examined by the one-way ANOVA and the Tukey-Kramer HSD test, to highlight strain-specific and species-specific differences among the isolates. A high degree of diversity appeared in the phenotypic and technological traits in opposition to a relatively low genotypic diversity. Although none of the isolates showed the best performances in all the activities, an appropriate mixture of strains could be selected for providing an efficacious autochthonous starter culture.     

An ADC histogram test based on small-amplitude waves

This paper deals with a new method improving the static test for analogue-to-digital converters. The method is based on a histogram procedure using as test signals small-amplitude triangular waves superimposed on suitable constant offset values. The histogram is built over the converter fullscale by varying the offset step by step systematically. A small amplitude and a reduced time slope in comparison to the converter range and slew rate, respectively, lead to static test conditions. This procedure allows inexpensive function generators to be used and the test duration to be dramatically reduced. Experimental results of tests aimed at validating, characterizing, and comparing the proposed method on two different converter architectures are presented.     

Error in the estimation of transition voltages with the standard histogram test of ADCs

In this paper we address the use of overdrive in the standard histogram test of analog to digital converters. The error in the estimation of the transition voltages due to the presence of additive noise is calculated and expressions for the minimum amount of overdrive required are presented. A comparison with previously published work is carried out.     

Role of practice tests in the accuracy of test predictions on text material.

Investigated the role of practice tests in predictions about test performance on texts. Generally, Ss predicted their relative performance on tests accurately. However, answering practice-test questions that were drawn from the same pool as criterion-test questions did not improve prediction accuracy. The main reason for this was that practice-test scores for specific texts did not correlate with criterion-test scores. In addition, neither practice tests that were identical to the criterion tests nor practice tests consisting of the question stems improved the accuracy of test predictions relative to no-practice tests. With identical practice and criterion tests, accuracy of self-generated feedback correlated positively with the accuracy of test predictions. For similar practice and criterion tests, however, accurate experimenter-provided feedback reduced test-prediction accuracy, presumably because of the lack of reliability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Differentiation of natural and synthetic phenylacetic acids by 2H NMR of the derived benzoic acids

The origin of 11 samples of phenylacetic acid 4, including those microbially produced from L-phenylalanine 1 and obtained by hydrolysis of penicillin G, has been studied by natural abundance deuterium NMR spectroscopy. The analysis performed on 4 failed since the (D/H) values relative to the aromatic ring nuclei and to the methylene moieties of the analysed phenylacetic acid samples resulted as similar. The permanganate oxidation of 4 into benzoic acid 5 allowed a differentiation in the ²H NMR spectrum of the signals of the ortho, meta and para nuclei of the aromatic ring, which instead for phenylacetic acid collapse in a single signal. Considering the deuterium content of the different positions in the aromatic ring, the differentiation between the natural rather than synthetic origin of the skeleton of the examined products was possible. The deuterium content of the aromatic ring for the synthetic materials is near to the statistical distribution, whereas for the products of natural derivation it follows a para>ortho>meta enrichment.     

Public Sector Alternatives to Water Supply and Sewerage Privatization: Case Studies

The paper presents a consideration of public sector operations as an alternative to the privatization of water and sewerage services. Cross-country case studies of publicly owned enterprises which have succeeded in reconciling efficiency and social purposes and carrying out structural and managerial changes are compared with some experiences of privatized concessions. Overall, public enterprises appear no less efficient that private companies, while being capable of development-oriented consideration of public interests.     

Stress test in the elderly. Clinical, hemodynamic, metabolic and electrocardiographic variables]

Pentylenetetrazol is a convulsive drug acting on gamma-aminobutyric acid-A (GABA[A]) gated-chloride receptors. In this study we used a subconvulsive dose (30 mg/kg) of pentylenetetrazol to induce a fully kindled state in rats. Glutamate receptors were evaluated using [3H]-[1(2-thienylcyclohexyl)]-piperidin (TCP) and [3H]kainate receptor autoradiography and [3H]muscimol autoradiography was used to study GABA(A) receptors. In fully kindled rats decreased N-methyl-D-aspartate receptor binding was found in parietal cortex, area CA2 of hippocampus and piriform cortex. Decreased kainate receptor binding was observed in all areas of the hippocampus, the medial amygdala and in the piriform cortex in the kindled rats. In contrast, GABA(A) receptor binding increased in the dentate gyrus. It is concluded that modulatory neuronal plasticity events are induced in fully pentylenetetrazol kindled rats, which appears to lead to decreased glutamatergic excitation and increased GABAergic inhibition in brain regions implicated in the development of seizure activity.     

Tetra-anionic porphyrin loading onto ZnO nanoneedles: A hybrid covalent/non covalent approach

A stepwise surface functionalization procedure, based on hybrid covalent and non-covalent approach is herein proposed to anchor tetra-anionic meso-tetrakis(4-sulfonatophenyl)porphyrin on ZnO nanorods. Carboxyalkylphosphonic acids have been proven effective to form stable self-assembled monolayers through the surface grafting of –PO₃H₂ headgroups. The exposed carboxylic functionalities are suitable for the successful grafting of cationic poly-l-lysine that drives, in water, the non-covalent anchoring of the anionic porphyrin. A stepwise surface characterization, provided by X-ray photoelectron spectroscopy, elucidates the multilayers deposition and surface composition after each process step, thus, giving interesting insights on the chemical speciation of the exposed functionalities. UV–vis spectroscopy confirms the role of ZnO morphology to increase the porphyrin loading onto the investigated surfaces. The proposed approach is effective to achieve deposition of anionic porphyrins on ZnO nanostructures and combines the robustness of covalent functionalization with the versatility and full reversibility of the non-covalent strategies.