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Domenico Colombrita Giuseppe Ravizzola Franco Pirali Giovanna Meloni Filomena Minelli Nicoló Narbone Dr. Adolfo Turano 《Current microbiology》1985,12(1):13-15
During a mean time of eight days, blood cultures made in duplicate with and without resins from nine patients with septicemia were evaluated. Data supporting the usefulness of blood cultures incorporating antibiotic absorbing resins as an index of chemotherapy are presented and discussed. The authors propose that this resin system be used not only to increase the sensitivity of blood cultures, but also as an index of effective chemotherapy. 相似文献
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† Patrizio Blandina Giovanna Cherici Flavio Moroni †George D. Prell †Jack Peter Green 《Journal of neurochemistry》1995,64(2):788-793
Abstract: The effect of pros -methylimidazoleacetic acid (p-MIAA) was measured on the release of glutamate and aspartate from cerebral cortex, hippocampus, and striatum of freely moving rats, and on the uptake of 14 C by striatal slices incubated in the presence of l -[14 C]-glutamate. Twenty-four hours after implantation of a dialysis fiber, striatum, hippocampus, or cerebral cortex spontaneously released both glutamate and aspartate in the micromolar range. p-MIAA (1 µ M to 1 m M ), added to the dialysis perfusate, elicited a concentration-dependent increase of glutamate release from striatum with a maximal increase of about threefold. This effect did not occur in hippocampus or cortex. In none of these regions did p-MIAA increase aspartate release significantly. The p-MIAA effect was not mimicked by its isomer tele -methylimidazoleacetic acid. p-MIAA did not influence the uptake of glutamate by striatal slices. The glutamate-releasing action of p-MIAA may affect striatal function and explain the positive correlation between levels of p-MIAA in CSF and the severity of Parkinson's disease. 相似文献
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Fabrizio Mattei Giovanna Schiavoni David F. Tough 《Cytokine & growth factor reviews》2010,21(4):227-236
Although initially identified and best characterized for their role in innate antiviral defence, type I interferons (IFN-I) are also known to have an important impact on the adaptive immune response. In part, this is linked to another long-recognised property of IFN-I, namely their ability to modify cellular proliferation and survival. Here, we review the influence of IFN-I on immune cell homeostasis, focusing on their effects on T cells and antigen-presenting cells. 相似文献
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Seventy strains of Zygosaccharomyces isolated from grape musts were investigated for their ability to produce higher alcohols and acetoin in synthetic medium and grape must. The Zygosaccharomyces strains produced generally low amounts of higher alcohols. Within this genus, Z. fermentati behaved differently from Z. bailii producing less isobutanol in synthetic medium and more amyl alcohols and isobutanol in grape must. Zygosaccharomyces fermentati did not form detectable amounts of acetoin in any conditions whereas Z. bailii produced it both in synthetic medium and in grape must. These strains were found to contribute to aroma and taste of wine. 相似文献
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Ashini Bolia Brian?W. Woodrum Angelo Cereda Melissa?A. Ruben Xu Wang S. Banu Ozkan Giovanna Ghirlanda 《Biophysical journal》2014,106(5):1142-1151
Cyanovirin-N (CVN), a cyanobacterial lectin, exemplifies a class of antiviral agents that inhibit HIV by binding to the highly glycosylated envelope protein gp120. Here, we investigate the energetics of glycan recognition using a computationally inexpensive flexible docking approach, backbone perturbation docking (BP-Dock). We benchmarked our method using two mutants of CVN: P51G-m4-CVN, which binds dimannose with high affinity through domain B, and CVN(mutDB), in which binding to domain B has been abolished through mutation of five polar residues to small nonpolar side chains. We investigated the energetic contribution of these polar residues along with the additional position 53 by docking dimannose to single-point CVN mutant models. Analysis of the docking simulations indicated that the E41A/G and T57A mutations led to a significant decrease in binding energy scores due to rearrangements of the hydrogen-bond network that reverberated throughout the binding cavity. N42A decreased the binding score to a level comparable to that of CVN(mutDB) by affecting the integrity of the local protein structure. In contrast, N53S resulted in a high binding energy score, similar to P51G-m4-CVN. Experimental characterization of the five mutants by NMR spectroscopy confirmed the binding affinity pattern predicted by BP-Dock. Despite their mostly conserved fold and stability, E41A, E41G, and T57A displayed dissociation constants in the millimolar range. N53S showed a binding constant in the low micromolar range, similar to that observed for P51G-m4-CVN. No binding was observed for N42A. Our results show that BP-Dock is a useful tool for rapidly screening the relative binding affinity pattern of in silico-designed mutants compared with wild-type, supporting its use to design novel mutants with enhanced binding properties. 相似文献