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The combination of localized 2D 1H MR correlation spectroscopy and Hadamard encoding allows the simultaneous acquisition of multiple volumes of interest without an increase in the experimental duration, compared to single-voxel acquisition. In the present study, 2D correlation spectra were acquired simultaneously within 20 to 40 min in two voxels located in each hemisphere of the rat brain. An intervoxel distance of 20% of the voxel size was sufficient to limit spatial contamination. The following cerebral metabolites gave detectable crosspeaks: N-acetylaspartate, the glutamate/glutamine pool, aspartate, phosphoethanolamine, glucose, glutathione, taurine, myo-inositols, lactate, threonine, ¿-aminobutyric acid, and alanine. Most of the metabolites were measured without contamination of other resonances. two-dimensional correlation 1H MRS

Exposure to cadmium is associated with the development of pulmonary damage such as emphysema and lung cancer. This metal is also a powerful inducer of stress proteins in many biologic models. The present study was undertaken to evaluate whether an overexpression of the heat shock protein (hsp)72 stress protein, which indicates repair of damaged proteins, could be a sensitive and early biomarker of environmental pollution by Cd. In comparative studies, we examined the effects of exposure to Cd (as CdCl(2)) on the growth rate of the A549 pulmonary cell line, and (by Western blot analyses) on the induction of the hsp72 stress protein and metallothioneins (MTs). CdCl(2) exposure was studied for periods of 2 hr to 1 month. For short-term exposure (2-6 hr) to Cd concentrations higher than 50 microM, an overexpression of hsp72 appeared 6 hr later, suggesting that hsp72 might be considered an early biomarker of acute exposure to Cd. For exposures lasting more than 4 days, lower doses of Cd (0.1-10 microM) similar to levels encountered in occupational exposure induced a significant increase of the hsp72 level. Because the increase of hsp72 occurs for doses that did not affect cell proliferation, our work supports the idea that its overexpression might be used as a sensitive indicator of occupational exposure to Cd. However, increased resistance to Cd appeared in A549 cells exposed for 1 month and overexpression of hsp72 disappeared simultaneously. It is possible that, in vivo, cell adaptation also occurs throughout chronic exposure to Cd, with a decrease of hsp induction as a consequence. A dose-related increase of MTs was found after 4 days of exposure to Cd concentrations ranging from 0.1 to 10 microM without change of overexpression during chronic exposure, suggesting that MT expression could be a more constant indicator of Cd pollution. Because 0.1 microM Cd (11 microg/L) induces hsp72 expression, showing the presence of damaged proteins, our work suggests that the maximum allowable biologic exposure limit should be lowered. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10

Nigella damascena L. (Ranunculaceae) originates from Magreb's countries (Morocco, Algeria, Tunisia, Egypt) and from the Middle Orient (Syria). In these countries the seeds are venerated by all the Muslim people and thus they are quoted in the Koran for their therapeutic effects.We evaluated the effects of different extracts isolated from Nigellae damascenae semen and Nigellae damascenae herba on three types of cells: THP1 cells (human monocytes which were used for evaluating the toxicity of the extracts) and two different forms of Leishmania infatum: promastigote cells and amastigote cells.Dichlormethanic extracts isolated from Nigellae damascenae semen and Nigellae damascenae herba were active on Leishmania promastigotes.Dichlormethanic extracts could be an alternative to the therapy based on pentamidine and amphotericin B.

The current study was undertaken to investigate the expression of stress proteins (HSP) in cultured human HT29 cells submitted to stressing events under in vitro conditions. Heat shocks (45 degrees C, for 15-60 min) or cold shocks (+ 1 degree C for 4 hr) were found to modify cell growth (growth curves) and to enhance HSP expression. In most cases, changes in HSP expression are much more pronounced than changes in cell growth. Exposure to 8% ethanol for 15 min resulted in both growth inhibition and HSP overexpression. Propanol-1 was found to be more toxic since 5% concentration given for 15 min stops cell growth. 2.5% propanol-1 for 15 min induces a slight reduction of cell growth but a clear-cut overexpression of stress proteins. We conclude that expression of stress proteins, especially those of the HSP68/70 family, constitutes a more sensitive response than changes in growth rate in case of external aggression. This could make our model an interesting biological sensor to environmental physical or chemical pollutants.