Influence of the incorporation of fibers in biscuit dough on proton mobility characterized by time domain NMR.

The effect of fiber addition on the distribution and mobility of protons in biscuits is studied by using low resolution time domain nuclear magnetic resonance (TD-NMR). The proportion of flour is reduced in order to incorporate inulin and oat fiber. NMR temperature dependent experiments are carried out in order to gain insight on the processes occurring in biscuit baking. Proton populations were identified measuring spin-spin relaxation times (T2). The major change in the relaxation profiles upon incorporation of fibers corresponds to mobile water molecules, which appear to be related to dough spreading behavior and biscuit quality. Biscuit samples baked in a commercial oven were studied by two dimensional spin-lattice/spin-spin (T1-T2) relaxation maps. The T1/T2 ratio is used as an indicator of the population mobility, where changes in the mobility of water in contact with flour components as starch, proteins and pentosans are observed.

Inhibition of development, swarming differentiation and virulence factors in Proteus mirabilis by an extract of Lithrea molleoides and its active principle (Z,Z)-5-(trideca-4',7'-dienyl)-resorcinol.

Antibacterial activity of Lithrea molleoides extract against Proteus mirabilis has been previously reported by our group. In the present study, the compound (Z,Z)-5-(trideca-4',7'-dienyl)-resorcinol (1) was isolated as its responsible active principle. The effects of the compound obtained and of L. molleoides extract on P. mirabilis growth and virulence factors were evaluated. Compound 1 showed MIC and MBC values of 4000 µg/ml. It was found that the extract, at four times the MIC, produced complete killing of the uropathogen at 2h from the beginning of the experiment, while the alkylresorcinol, at four times the MIC, produced the same effect after 24 h. Hemolysis was adversely affected in treatments with both products at 8 µg/ml, while hemagglutination was not altered. The whole extract induced complete autoaggregation of P. mirabilis at 2000 µg/ml, while compound 1 at the same concentration did not show this property. Swarming motility was delayed in treatments with the extract and with 1 at 1000 and 8 µg/ml, respectively, at 8h from the beginning of the assay. Complete inhibition of the phenomenon was still observed after 24 h when compound 1 was added at 125 µg/ml. These findings offer the possibility of new classes of antimicrobial medicines to tackle infections caused by P. mirabilis.

Fast measurements of average flow velocity by Low-Field ¹H NMR.

In this paper, we describe a method for measuring the average flow velocity of a sample by means of Nuclear Magnetic Resonance. This method is based on the Carr-Purcell-Meiboom-Gill (CPMG) sequence and does not require the application of any additional static or pulsed magnetic field gradients to the background magnetic field. The technique is based on analyzing the early-time behavior of the echo amplitudes of the CPMG sequence. Measurements of average flow velocity of water are presented. The experimental results show a linear relationship between the slope/y-intercept ratio of a linear fit of the first echoes in the CPMG sequence, and the average flow velocity of the flowing fluid. The proposed method can be implemented in low-cost Low-Field NMR spectrometers allowing a continuous monitoring of the average velocity of a fluid in almost real-time, even if the flow velocity changes rapidly.

Alteración de los sistemas antinociceptivos en las cefaleas crónicas diarias / Alteration of the antinociceptive systems in chronic daily headaches

Introducción. La cefalea crónica diaria (CCD) es un cuadrodoloroso crónico frecuente en la práctica neurológica. El diagnósticoes clínico y el abordaje terapéutico resulta complejo. No estáclaro todavía cuál es su mecanismo de producción, pero se reconoceun componente genético como factor predisponente. Son múltipleslas áreas que participan en la generación de cefaleas primarias,entre las que se encuentra la sustancia gris periacueductal (SGPA),que participa como neuromoduladora tanto en cefaleas como enotros cuadros dolorosos crónicos. Objetivos. Para evaluar posiblescambios bioquímicos en pacientes con CCD se estudiaron los espectrospor resonancia magnética en la SGPA. Sujetos y métodos. Seestudiaron los espectros en la SGPA en 17 pacientes con CCD y secompararon con el espectro promedio de 17 sujetos sanos a travésdel análisis espectroscópico diferencial. Resultados. Los sujetos conCCD presentan una reducción mayor del 70% del metabolito N-acetilaspartato glutamato (NAAG) en la SGPA. El NAAG es un péptidorelacionado con actividad antinociceptiva. Conclusión. La reduccióndel NAAG en la SPGA sugiere una alteración de la neuromodulaciónde sistemas antinociceptivos en sujetos con CCD. Queda pendientede que se establezca si la CCD es la causa o la consecuencia

Introduction. Chronic daily headache (CDH) is a chronic painful clinical condition that is frequently found inneurological practice. Diagnosis is clinical and the therapeutic approach is complex. Its mechanism of production is still notaltogether clear, but a genetic component is acknowledged as a predisposing factor. Numerous areas are involved in thegeneration of primary headaches, including the periaqueductal grey matter (PAGM), which plays a role as a neuromodulatorboth in headaches and in other chronic painful conditions. Aims. In order to evaluate possible biochemical changes inpatients with CDH, magnetic resonance imaging was used to study the spectra produced in the PAGM. Subjects and methods.The spectra in the PAGM were studied in 17 patients with CDH. These were compared with the average spectra in 17 healthysubjects by means of differential spectroscopy. Results. Subjects with CDH show a reduction of over 70% in the level of themetabolite N-acetyl-aspartyl-glutamate (NAAG) in the PAGM. NAAG is a peptide involved in antinociceptive activity. Conclusions.The reduction of NAAG in the PAGM suggests altered neuromodulation of the antinociceptive systems in subjects with CDH.Whether CDH is the cause or the consequence has still to be determined

[Alteration of the antinociceptive systems in chronic daily headaches]. / Alteracion de los sistemas antinociceptivos en las cefaleas cronicas diarias.

INTRODUCTION: Chronic daily headache (CDH) is a chronic painful clinical condition that is frequently found in neurological practice. Diagnosis is clinical and the therapeutic approach is complex. Its mechanism of production is still not altogether clear, but a genetic component is acknowledged as a predisposing factor. Numerous areas are involved in the generation of primary headaches, including the periaqueductal grey matter (PAGM), which plays a role as a neuromodulator both in headaches and in other chronic painful conditions. AIMS: In order to evaluate possible biochemical changes in patients with CDH, magnetic resonance imaging was used to study the spectra produced in the PAGM. SUBJECTS AND METHODS: The spectra in the PAGM were studied in 17 patients with CDH. These were compared with the average spectra in 17 healthy subjects by means of differential spectroscopy. RESULTS: Subjects with CDH show a reduction of over 70% in the level of the metabolite N-acetyl-aspartyl-glutamate (NAAG) in the PAGM. NAAG is a peptide involved in antinociceptive activity. CONCLUSIONS: The reduction of NAAG in the PAGM suggests altered neuromodulation of the antinociceptive systems in subjects with CDH. Whether CDH is the cause or the consequence has still to be determined.