The impact of grape processing and carbonic maceration on the microbiota of early stages of winemaking.

AIMS: The work investigates the impact of grapes processing at the beginning of winemaking on the composition of microbiota during the oenological fermentations and on the composition of obtained wines. METHODS AND RESULTS: The experiments were conducted in a biodynamic winery to exclude interference due to microbial starters. Three winemaking protocols, with different pre-fermentative management of grapes, were followed by plate count and next generation sequencing on 16S for bacteria and internal transcribed spacer sequencing (ITS) for yeast. Chemical and sensory characterization of wine was performed. The grape processing influenced the evolution of microbiota (especially lactic and acetic acid bacteria) and the fermentation rate. The highest biodiversity was observed in the experiment carried out with whole grapes and carbonic maceration, with the presence of bacterial groups not usually found in winemaking (Bacteroidales, Clostridiales, Oscillospira). The different microbiotas influenced the organic acid profile of wines, the content of biogenic ammines and the perception of organoleptic descriptors linked to the vine cultivar (Syrah). CONCLUSIONS: Carbonic maceration impacts on the evolution of the microbiota and the wine features. The absence of addition of starters and sulphur dioxide would seem to be correlated with the high microbial biodiversity. SIGNIFICANCE AND IMPACT OF THE STUDY: Carbonic maceration is a traditional winemaking practice, today there are difficulties in its managing because the anaerobiosis stimulates spoilage micro-organisms. The work elucidates the reasons of these difficulties and identified some microbial groups rarely associated with winemaking. The ratio of ethanol accumulation along with physical management of grapes and the supply of oxygen during the early stages of winemaking are powerful instruments of oenological variability, able to offer new possibilities to winemakers in order to defining the quality of red wines.

Genetic and phenotypic diversity of autochthonous Saccharomyces spp. strains associated to natural fermentation of 'Malvasia delle Lipari'.

AIMS: Characterize from both genetic and phenotypic standpoints the indigenous strains of Saccharomyces spp. associated with natural fermentation of 'Malvasia delle Lipari'. METHODS AND RESULTS: A total of 192 yeast isolates were obtained from completed fermentation of a mix of 'Malvasia delle Lipari' (92%) and 'Corinto nero' (8%) grapes in two wineries in Salina Island (Sicily, Italy). Fifty-one Saccharomyces spp. isolates were characterized using ITS-PCR, random amplified polymorphic DNA-PCR and mitochondrial DNA restriction fragment length polymorphism and 12 biotypes were identified. Representative strains of each biotype, tested for their physiological traits, exhibit different killer activity, fermentation vigour, production of hydrogen sulphide and show similar beta-glucosidase and proteolytic activity. CONCLUSIONS: It is possible to cluster in different groups naturally occurring indigenous biotypes of Saccharomyces cerevisiae from 'Malvasia delle Lipari' on the basis of molecular profiles. SIGNIFICANCE AND IMPACT OF THE STUDY: Deeper insight on indigenous wine yeast of a conserved environment. The knowledge gained might offer a contribution to the selection of autochthonous wine yeast as starters for controlled fermentations.

Investigation into the role of the truncated denitrification chain in Rhizobium sullae strain HCNT1.

Most denitrifying bacteria reduce nitrate to the inert gases nitrous oxide or nitrogen. A remarkable exception to this is Rhizobium sullae strain HCNT1, which catalyses only a single step in the denitrification pathway, the reduction of nitrite to the reactive molecule nitric oxide. Further study demonstrated that HCNT1 does not encode the genes for NO reductase. Prolonged incubation of HCNT1 under anoxic conditions revealed that the cells had reduced culturability but not viability when nitrite was present. This may indicate an adaptation to anoxic conditions to provide resistance to environmental stresses. A closely related strain of R. sullae, strain CC1335, which is unable to denitrify, was found to lose culturability but not viability irrespective of the presence of nitrite. When the gene for nitrite reductase was mobilized into CC1335, this increased culturability with or without nitrite. These results indicate that the presence of nitrite reductase can influence the long-term survival of R. sullae strains and may provide an explanation as to why HCNT1 possesses this unusual truncation of its denitrification electron transport chain.

Gemination of maxillary incisors.

Gemination is defined as a shape anomaly of teeth caused by an incomplete division of a single tooth bud. Its aesthetic and functional implications usually require a complex endodontic, restorative, periodontal, surgical, and orthodontic treatments. Three cases of gemination of maxillary incisors, resolved by different therapeutic approaches, are reported. The 1st case (germination of 2.1) was resolved by a simple crown-plasty. The 2nd case (gemination of 1.1 and 2.1) was resolved by a crown-plasty of 2.1 and an interradicular section of 1.1 with extraction of lateral root. The 3rd case (2.2 supernumerary and gemination of 1.2) was resolved by sacrifice of 1.2, extraction of 2.2 and its implantation in 1.2 region. In order to obtain an acceptable aesthetic and functional restoration, as in the cases presented, a good team-work, where all the specialists contribute to the selection of the more suitable treatment possible, is mandatory.

Intracranial dislocation of the mandibular condyle: report of two cases and review of the literature.

Fractures of the mandibular condylar process are common and account for up to 40% of all mandibular fractures. Penetration of the condylar head into the middle cranial fossa is, however, rare. We have found reports of only 43 cases since 1834. The diagnosis of intracranial condylar dislocation is difficult, there are usually no particular symptoms or neurological signs. As a result, detailed radiological studies are necessary. In the absence of clear radiographic images of the condylar structures, computed tomography (CT) is essential to locate the fragments and to investigate and monitor intracranial lesions. This paper describes the diagnostic and surgical procedures used in two cases of condylar dislocation and discusses them with reference to previous cases. The use of a titanium screw, which was positioned intracranially in the first case, has not, to our knowledge, been described previously.

Analysis of the role of the nnrR gene product in the response of Rhodobacter sphaeroides 2.4.1 to exogenous nitric oxide.

Rhodobacter sphaeroides 2.4.1, which is incapable of denitrification, has been found to carry nnrR, the nor operon, and nnrS, which are utilized for denitrification in R. sphaeroides 2.4.3. The gene encoding nitrite reductase was not found in 2.4.1. Expression of beta-galactosidase activity from a norB-lacZ fusion was activated when cells of 2.4.1 were incubated with NO-producing bacteria. This result indicates that the products of nnrR and the genes flanking it are utilized when 2.4.1 is growing in an environment where denitrification occurs.

Characterization of the gene encoding nitrite reductase and the physiological consequences of its expression in the nondenitrifying Rhizobium "hedysari" strain HCNT1.

Rhizobium "hedysari" HCNT1 is an unclassified rhizobium which contains a nitric oxide-producing nitrite reductase but is apparently incapable of coupling the reduction of nitrite to energy conservation. The gene encoding the nitrite reductase, nirK, has been cloned and sequenced and was found to encode a protein closely related to the copper-containing family of nitrite reductases. Unlike other members of this family, nirK expression in HCNT1 is not dependent on the presence of nitrogen oxides, being dependent only on oxygen concentration. Oxygen respiration of microaerobically grown Nir-deficient cells is not affected by concentrations of nitrite that completely inhibit oxygen respiration in wild-type cells. This loss of sensitivity suggests that the product of nitrite reductase, nitric oxide, is responsible for inhibition of oxygen respiration. By using a newly developed chemically modified electrode to detect nitric oxide, it was found that nitrite reduction by HCNT1 produces significantly higher nitric oxide concentrations than are observed in true denitrifiers. This indicates that nitrite reductase is the only nitrogen oxide reductase active in HCNT1. The capacity to generate such large concentrations of freely diffusible nitric oxide as a consequence of nitrite respiration makes HCNT1 unique among bacteria.

Electrocatalytic reduction of nitric oxide at electrodes modified with electropolymerized films of [Cr(v-tpy)2]3+ and their application to cellular NO determinations.

Nitric oxide can be electrocatalytically reduced at electrodes modified with electropolymerized films of [Cr(v-tpy)2]3+. Upon further modification with a thin film of Nafion (to prevent interferences from anions, especially nitrite), these electrodes can be employed as NO sensors in solution with submicromolar detection limits and fast response. We have carried out preliminary studies of cellular NO release from Rhodobacter sphaeroides bacterial cells with excellent results.

[The Gorlin-Goltz syndrome. A report of 2 cases]. / Sindrome di Gorlin-Goltz. Osservazione di due casi.

Two cases of patients with Gorlin-Goltz syndrome are described. The Gorlin-Goltz syndrome is a polydistrectual, hereditary disease characterized by multiple keratocysts and basocellular nevomatosis. It is pointed out that the inconstancy of the main symptoms makes early diagnosis difficult. The histologic characteristics of odontogenic keratocysts and the possible etiopathogenetic relations between cystic lesions and hamartia of adjacent oral mucosa, as considered by Stoelinga, are also discussed. In view of the course of the cases presented, a surgical approach considering such potential findings, is supposed to favorably affect the clinical evolution in respect to a high relapsing drift.