Features of basidiomycetous yeasts from grapes and apples associated with crop environment and fermenting juice.

AIMS: The characterization of grape and apple yeasts was carried out to investigate the ecology of basidiomycetes associated with crop environment and fermenting juice. METHODS AND RESULTS: A total of 15 basidiomycetous strains were analysed for plant-growth promoting properties, sensitivity to fungicides and features related to their survival in fermenting juice (low pH, SO2 and ethanol sensitivity). Only one strain displayed 1-aminocyclopropane-1-carboxylate deaminase activity, whereas other strains were able to produce ammonia and indole-3-acetic acid, solubilize calcium phosphate, and display catalase activity and antagonism against Botrytis cinerea. Strains presented great variability in their sensitivity to fungicides. Rhodotorula mucilaginosa Yl26 and Sporobolomyces agrorum PYCC 8108T displayed low sensitivity to all fungicides, with high tolerance to SO2 and ethanol, and were able to survive in fermenting grape and apple juice. CONCLUSIONS: This study revealed the diversity of basidiomycetous yeasts in the important physiological traits that affect their growth, either in the crop environment or in fermenting juice. SIGNIFICANCE AND IMPACT OF THE STUDY: Identify the possibility of selective effects of fungicide treatments on basidiomycetous yeasts that could offer benefits for grapevines and apple trees, as well as the survival of strains that are better adapted to fermenting juice and that potentially have a role in the aroma of beverages.

Mesocosm-based simulations to optimize a bioremediation strategy for the effective restoration of wildfire-impacted soils contaminated with high-molecular-weight hydrocarbons.

AIMS: We obtained four microbial isolates from soil exposed to forest fire and evaluated their potential bioremediation activity when combined with a biosurfactant-producing bacterial strain for the decontamination of wildfire-impacted soil polluted with high-molecular-weight (HMW) hydrocarbons. METHODS AND RESULTS: We established mesocosm trials to compare three bioremediation strategies: natural attenuation, bioaugmentation and biostimulation. Chemical analysis, culture-dependent and culture-independent methods were used to evaluate the bioremediation efficiency and speciation of the microbial cenoses based on these approaches. After treatment for 90 days, bioaugmentation removed 75·2-75·9% of the HMW hydrocarbons, biostimulation removed 63·2-69·5% and natural attenuation removed ~22·5%. Hydrocarbon degradation was significantly enhanced in the mesocosm supplemented with the biosurfactant-producing bacterial strain after 20 and 50 days of treatment compared to the other bioremediation strategies. CONCLUSIONS: We found that the bioaugmentation approach was more effective than biostimulation and natural attenuation for the removal of HMW hydrocarbons from fire-impacted soil. SIGNIFICANCE AND IMPACT OF THE STUDY: Our study showed that micro-organisms from wildfire-impacted soil show significant potential for bioremediation, and that biosurfactant-producing bacterial strains can be combined with them as part of an effective bioremediation strategy.

Diabetes mellitus: new therapeutic approaches to treat an old disease

Diabetes mellitus is a widespread disease whose frequency increases constantly and is expected to reach alarming levels by the year 2025. Introduction of insulin therapy represented a major breakthrough; however, a very strict regimen is required to maintain blood glucose levels within the normal range and to prevent or postpone chronic complications associated with this disease. Frequent hyper- and hypoglycemia seriously affect the quality of life of these patients. Reversion of this situation can only be achieved through whole organ (pancreas) transplant or pancreatic islet transplant, the former being a high-risk surgical procedure, while the latter is a much simpler and may be accomplished in only 20-40 min. The advantages and perspectives of islet cell transplantation will be discussed, in the light of tissue engineering and gene therapy. Ongoing research carried out in our laboratory, aimed at developing clinical cell and molecular therapy protocols for diabetes will also be focused

Mg(2+)-mediated binding of 6-substituted quinolones to DNA: relevance to biological activity.

The interaction of a number of novel 6-substituted quinolone derivatives with DNA in the presence/absence of magnesium ions has been investigated by fluorometric techniques. The drug-single-stranded nucleic acid interaction is invariantly mediated by the metal ion. In all cases optimal complex formation is found at physiological Mg2+ concentration. From titrations at different [Mg2+] the binding constant for the ternary drug-DNA-Mg2+ complex (KT) has been evaluated. Interestingly, a good relationship is found between KT and gyrase poisoning activity of the test quinolones (IC50), which confirms that DNA-affinity of the quinolone, modulated by Mg2+, plays an important role in poisoning the cleavable gyrase-DNA complex and, consequently, in eliciting antibacterial activity in this family of drugs. The results obtained with different 6-substituted compounds supports the idea that position 6 of the drug, besides playing a pharmacokinetic role, is involved in recognition of the enzyme pocket. Our data do not support a mechanism of action based upon quinolone intercalation into B-DNA.

Quantitative study of the myelinated fibers in the communicating branch between the hypoglossal and lingual nerves in man.

The present study assessed the number and diameter of myelinated fibers in the communicating branch between the hypoglossal and lingual nerves in man, with a view toward correlating their diameters with possible functions. In four cases, a mean of 806 (SD: 227 - minimum: 637 - maximum: 1127) myelinated fibers were counted in the communicating branch. Diameters ranged between 1 and 17 microns, and the frequency distribution was represented by a bimodal curve with peaks at 3-5 microns.

Effects of corpus callosum stimulation on the morphology and frequency of epileptic bursts in the feline topical penicillin generalized model.

Twelve cats were stimulated at the rostrum of the corpus callosum while full epileptic activity was recorded after topical application of penicillin on the cortex bilaterally. Electrocorticography was performed bilaterally. In 6 animals the electrode position was checked by evoked potentials. Stimulation parameters ranged from 0.5 to 1,000 Hz, from 2 to 10 mA, and from 0.5 to 5.0 ms. No significant modification was found in frequency, synchrony, and morphology of the epileptic bursts and spikes, suggesting that callosal stimulation, at least using this model, is ineffective in reducing epileptic activity.