Assessment of Biolog EcoplateTM method for functional metabolic diversity of aerotolerant pig fecal microbiota.

In the last decades, gut microbiota and its role in mammal host development and health have been increasingly investigated. Metabolites produced by gut microbiota can affect intestinal homeostasis and immune system maturity and activation, and in turn, they can influence the health and growth performance of livestock. Therefore, a better understanding of the functional metabolic capability of the gut microbiota would be appreciated by the scientific community. In this study, the BiologTM Ecoplates technology was applied for studying the metabolic potential of the aerotolerant microbial community of pig fecal samples, evaluating the interference of different storage conditions and cell concentrations. The length of time for which a fecal sample maintained detectable and unchanged microbial metabolic activity was also investigated. Two assays aimed to evaluate differences in the metabolic activities between fresh and snap-frozen fecal samples at different dilutions and at different lengths of times of preservation at -80°C were carried out. The biodiversity and the predicted functionality of the entire bacterial community through a targeted metagenomic approach were also explored. The results highlighted that snap freezing of fecal samples preserved the metabolic activity of the microbial community when compared to fresh feces. Sample storage at -80 °C did not significantly affect the metabolic activity of the microbial community, which was stable for 150 days. Furthermore, the highest metabolic activity was detected with 1:2 to 1:5 dilutions of the stock suspension. BiologTM Ecoplates technology is a rapid and useful method to explore microbial communities' metabolism in animal fecal samples contributing to investigate host animal physiology. KEY POINTS: • Freezing of samples can preserve the functional activity of the aerotolerant microbial community for 150 days. • The concentration of microbial cells strongly influences metabolic activity detection. • Sequencing coupled with the BiologTM Ecoplates could be a strategy to evaluate the metabolic potential of the microbiota of the fecal sample.

Thermal haemolytic threshold of human erythrocytes.

Haemolytic thermal threshold of human erythrocytes has been determined by means of an especially designed microwave apparatus. Temperatures between 50 and 55 degrees C are necessary to produce an initial haemolysis of erythrocytes in the whole blood, while the thermal threshold drops to 37 degrees C for red blood cells suspended in buffered saline. Absorbed energy measurements permit the conclusion that the haemolytic effect is thermal in nature.

Exposure of workers to intense RF electric fields that leak from plastic sealers.

This paper presents the results of an environmental investigation in a plastic-ware industry using RF sealers. Environmental measurements have demonstrated the presence of strong electric fields the intensity of which: reaches significant levels from the health-protection point of view only in proximity to the applicators; often exceeds the maximal levels allowed by all standards (including the most permissive) for short duration exposures, especially in the region of the hands. Results of a cross-sectional study on the health of 63 female workers are related to the observed RF exposure. A statistically significant correlation was found to exist between RF exposure and some minor health effects--eye irritation, upper limb paresthesias, and vitreous body disorganization.

Molecular sensory physiology of Euglena.

After a short description of the motile physiology of Euglena gracilis the responses to light stimulation are analyzed and a new nomenclature is proposed concerning flagellar motility variations. A discussion follows about the characteristics of the photoreceptive system of Euglena and about the flavinic nature of its phototactic pigments.

A health examination of railway high-voltage substation workers exposed to ELF electromagnetic fields.

This is a cross-sectional survey on the health conditions of railways workers active in 258 interconnection and conversion substations all over Italy. Measurements performed in both kinds of substations operating at 220 kV have shown that maximum levels of the electric field strength and of the magnetic flux density at 50 Hz are of the order of 5 kV/m and 15 microT, respectively. Three subject groups, differently exposed (1, 10, 20 h/week), and an unexposed control group, for a total number of 627 workers, constitute the population at study. All subjects underwent a general medical examination, laboratory investigations, and a series of selected examinations relative to three systems (nervous, cardiovascular, and haematopoietic) considered at higher risk. No differences have been found between the exposed and the control groups. It is concluded that workers exposed to ELF electromagnetic fields of moderate strength do not show the presence of clear effects on their state of health.

Spectroscopic properties and related functions of the stigma measured in living cells of Euglena gracilis.

The spectroscopic properties of stigma inside green and dark-grown cells and of isolated stigma globules have been studied by means of a microspectrophotometer build in the Laboratory. On the base of these results and of the analysis of the absorption spectra of a stigma suspension, cell suspension and the cell methanolic extracts, it can be inferred that pigments localized in the stigma are free carotenoids which are not closely packed and do not show an ordered arrangement. Furthermore, the efficiency of the stigma as shading device is duscussed.

Reliability of microwave heating for hemoderivative thawing.

The spoiling of coagulation factors, proteic patterns and specific activity has been comparatively determined in fresh frozen plasma, cryoprecipitates and hemodiagnostic sera, thawed in a 37 degrees C water bath and in a microwave oven. Effects of conventional and microwave heating are not significantly different, while results of the latter technique are rapid and aseptic. Previously, heating performances of a commercial microwave oven have been investigated for deionized water, saline solutions, and bovine serum. Furthermore, plastic containers of hemoderivatives have been tested to assure that no toxic products are released during microwave heating.

Measurement of enzymatic activation energy by continuous heating with microwaves.

A microwave heating method and an associated numerical method for computing the reaction velocities in a single experiment are proposed for rapid determination of the activation energy of enzymatic reactions. Application of this new technique to different enzymatic reactions is reported.

Analysis of the effects of microwave energy on enzymatic activity of lactate dehydrogenase (LDH).

Interactions between microwave energy (3 GHz) and the enzyme Lactate Dehydrogenase (LDH) have been analyzed by monitoring the enzymatic activity during irradiation in steady-state or dynamic conditions, by irradiating the sample with variable power levels (up to 6 W into the sample) and, finally, by knowing accurately the true specific absorption rate. No permanent or temporary changes can be induced when the energy absorption does not cause a temperature variation. For higher energy values, effects are purely thermal in nature. Furthermore the thermal activation of the reaction velocity, caused by microwave irradiation, is in itself sufficient to give a good fit with the experimental time evolution of the enzymatic reaction.