Detection of β‐Glucosidase and Esterase Activities in Wild Yeast in a Distillery Environment

The study of β‐glucosidase and esterase in wild yeast, the enzymatic activities of which contribute to the distinctive flavours of grape‐derived alcoholic beverages, was the aim of this work. The study focused on wild yeast isolated from grape pomace and on identifying strains with interesting characteristics by examining their electrophoretic profiles. Zymograms revealed a high level of polymorphism. Some of these wild yeasts may be of interest for improving the quality of the distillate. This study also highlights the necessity of associating enzymatic properties to various environmental conditions, since these play an important role in the expression of wild yeast performance.     

Updating on the lysinoalanine content of commercial infant formulae and beicost products

Since the safety issue of lysinoalanine (LAL) still remains unresolved, its concentration in infant formulae should be reduced to a minimum. Data collected in the 1980s indicated that LAL is formed in higher amounts in liquid than in powdered formulae. Recently the market of liquid infant formulae is increasing rapidly and there are no new data, so 23 commercial powdered or liquid samples were investigated. In powdered samples, LAL was below the detection limit, whereas liquid adapted formulae contained up to 86 μg/g protein, liquid follow-on formulae up to 390 μg/g protein, and liquid growing milks up to 514 μg/g protein. The concentration of LAL in liquid formulae is considerably lower than in the past; however, the level in a few products remains rather high, especially compared with normal UHT-treated milk. Great differences were observed among products of different companies, which suggests that labelling with the thermal treatment applied would be very advisable. The investigation of some beicost products indicates that LAL is present only in products certainly containing milk proteins. Considering the rather low levels in comparison with liquid infant formulae, the contribution of beicost products to the total LAL daily intake does not seem to be particularly relevant.     

Genome renewal: A new phenomenon revealed from a genetic study of 43 strains of Saccharomyces cerevisiae derived from natural fermentation of grape musts

We have analyzed by genetic means 43 strains of Saccharomyces that had been isolated from fermenting grape musts in Italy. Twenty eight of these strains were isolated from 28 cellars in the Region of Emilia Romagna. The other 15 strains came from 5 fermentations at four cellars near the city of Arpino, which is located south and east of Rome. We found that 20 of the 28 strains from Emilia Romagna were heterozygous at from one to seven loci. The balance were, within the limits of our detection, completely homozygous. All these strains appeared to be diploid and most were homozygous for the homothallism gene (HO/HO). Spore viability varied greatly between the different strains and showed an inverse relation with the degree of heterozygosity. Several of the strains, and in particular those from Arpino, yielded asci that came from genetically different cells. These different cells could be interpreted to have arisen from a heterozygote that had sporulated and, because of the HO gene, yielded homozygous diploid spore clones. We propose that natural wine yeast strains can undergo such changes and thereby change a multiple heterozygote into completely homozygous diploids, some of which may replace the original heterozygous diploid. We call this process ‘genome renewal’.     

Clinical tolerance of oral loading with elevated doses of amiodarone in a group of patients with heart failure

Amiodarone is a choice drug for the treatment of patients suffering from life-threatening hyperkinetic ventricular arrhythmias and depressed ventricular function. The drug is characterized by a remarkably long halflife and a delayed initial activity after oral administration of the usual loading levels. The aim of this study was to establish: -the clinical tolerance to elevated doses in patients with heart failure presenting complex, hyperkinetic ventricular arrhythmias; -the possibility to shorten hospitalization as a result of the oral loading; -whether this administration route would take less time to be efficacious. For this purpose, 30 patients with heart failure and complex, hyperkinetic ventricular arrhythmias were treated with 0.50 mg/kg body weight of amiodarone for three days and with 0.30 mg/kg on the 4th and 5th days, followed by a maintenance period of treatment with 200-400 mg daily. All patients underwent a 24-h Holter test before and after administration and an echocardiographic examination showing an average ejection fraction of approximately 30%. Amiodarone was clinically well tolerated; only 2 patients required discontinuation of therapy whereas, among the the remaining 28 patients, 2 cases of transient hypotension and 3 cases of gastroenteric disorders were observed. It was concluded that elevated doses of amiodarone were well tolerated, which allowed to reduce the loading period and, therefore, hospitalization.     

Influence of the cytochrome P4502D6*4 allele on the pharmacokinetics of controlled-release metoprolol

Unexplained elevations of maternal serum alpha-fetoprotein exist in approximately 1% of the obstetric population. A consensus has been reached that these women face an increased risk of adverse pregnancy outcome. Whether their overall risk can be altered by the currently available surveillance modalities, however, remains controversial. Current research has focused on identifying those pregnancies with the highest risks of either fetal growth restriction, pre-eclampsia, preterm delivery or intrauterine fetal demise. Markedly increased maternal serum alpha-fetoprotein (over 4.0 multiples of the median), elevations of other serum markers such as human chorionic gonadotropin and abnormal umbilical Doppler flow are associated with the greatest risk of poor pregnancy outcome. When initiating surveillance of the pregnancy with unexplained elevated maternal serum alpha-fetoprotein consideration of these factors is receiving increased attention.     

Agent-based models for first- and second-order emergent collective behaviours of social amoeba <Emphasis Type="Italic">Dictyostelium discoideum</Emphasis> aggregation and migration phases

Collective behaviour in nature provides a source of inspiration for engineering artificial systems (e.g. robotics, ecosystems of services), due to their inherent mechanisms favouring adaptation to environmental changes and enabling complex emergent behaviour to arise from a relatively simple behaviour of individual entities. The first-order emergence, also referred to as swarm intelligence, is well studied, while higher order levels of emergent behaviour have not received much attention yet. Second-order emergent behaviour arises from the interactions of individuals, which are themselves the result of first-order emergent behaviour. Dictyostelium discoideum provides a compelling case for studying both first- and second-order emergence. Individual cells move around on their own when there is plenty of food. When food is scarce, cells self-aggregate towards a leading center cell (first-order emergent behaviour) to build a super-organism, similar to a slug. The slug displays properties that none of the cells has on its own (e.g. sensitivity to light and heat). It moves as a whole (second-order emergent behaviour) looking for a suitable place to transform into a fruiting body (also known as sporocarp), where later the cells resume their individual behaviour. This paper focuses specifically on the aggregation and migration phases of Dictyostelium discoideum. We present two agent-based models, implemented in Matlab for first order and Python for second order. They display a series of emergent properties, among others homogeneous aggregation territories size (first order) and merging of slugs or new property as sensitivity to light (second order). Future works involve implementing and experimenting both first- and second-order emergence in swarm robotics, and identification of design patterns for engineering higher order emergent behaviour in artificial systems.     

Thermal behavior of thermoplastic polymer nanocomposites containing graphene nanoplatelets

Polypropylene (PP), acrylonitrile butadiene styrene (ABS), and thermoplastic polyurethane (TPU) nanocomposites filled with 5 wt % of two different kinds of commercially available graphene nanoplatelets (GNPs) were prepared. Composites materials were characterized in terms of thermal properties (thermal conductivity and thermal stability) in order to study the effect of different fillers within different thermoplastic matrices. The exfoliation process and the mechanical properties were also investigated. We chose three different thermoplastic polymers (polyolefin, copolymer and elastomer) to cover a wide range of thermoplastic materials and identify a guideline in the use of GNPs for nanocomposite materials. No drastic differences were observed in terms of mechanical properties when the same matrices were filled with different GNPs. Concerning thermal conductivity, it was observed that the GNPs plane dimensions play a crucial role in the increase of conductive properties. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44814.     

Muscle discretization affects the loading transferred to bones in lower-limb musculoskeletal models

Modelling the mechanical effect of muscles is important in several research and clinical contexts. However, few studies have investigated the effect of different muscle discretizations from a mechanical standpoint. The present study evaluated the errors of a reduced discretization of the lower-limb muscles in reproducing the muscle loading transferred to bones. Skeletal geometries and a muscle data collection were derived from clinical images and dissection studies of two cadaver specimens. The guidelines of a general method previously proposed for a different anatomical district were followed. The data collection was used to calculate the mechanical effect of muscles, i.e. the generalized force vectors, and the errors between a large and a reduced discretization, in a reference skeletal pose and in the extreme poses of the range of motion of joints. The results showed that the errors committed using a reduced representation of muscles could be significant and higher than those reported for a different anatomical region. In particular, the calculated errors were found to be dependent on the individual anatomy and on the skeletal pose. Since different biomechanical applications may require different discretization levels, care is suggested in identifying the number of muscle lines of action to be used in musculoskeletal models.