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Crayfish utilize aquatic plants as a food source and may concentrate pollutants, such as heavy metals. Monitoring the possible heavy metal presence in crayfish edible tissues is therefore important since crayfish can be part of the human diet. In this study we have analysed specimens of Cherax destructor of two different sizes coming from a crayfish farm, with respect to heavy metal (lead, copper, cadmium, chromium, zinc) concentrations in the muscle, hepatopancreas and exoskeleton. Furthermore, the metal concentrations were determined in water, sediment and in plants. Our data show that the contents of lead, copper, cadmium, chromium and zinc, are higher in the tissues with respect to water, indicating in some cases their bioaccumulation in Cherax destructor. The content of lead and zinc in sediment and plants the animals feed on, was higher than in tissues and organs, suggesting that biomagnification does not occur for these heavy metals. Copper and chromium show biomagnification in all tissues, while cadmium only in the hepatopancreas.

The objective of this study was to characterize the insoluble and soluble dietary fiber present in Argentine and Italian artichoke (Cynara scolymus) by-products by comparing chemical analysis and ATR-FTIR spectroscopy. Non-edible bracts of Argentine (AR) and Italian (Benevento (BN) and Sicily (SC)) artichoke cultivars were employed. The soluble and insoluble dietary fibers were extracted by physical procedures and determined by chemical, attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, and chemometric analysis (principal components analysis, PCA). No differences in total dietary fiber content between AR and SC samples were observed, although they both showed higher values than BN. With respect to insoluble fiber, this fraction represents 82.5%, 63.5%, and 55.2% of the total dietary fiber for BN, SC and AR, respectively. Fibers from AR presented different compositions and structures, as determined by ATR-FTIR, compared to those of the Italian cultivars (BN and SC). Comparing the results of dietary fiber measured by ezymogravimetric assay with those obtained by ATR-FTIR and PCA, we conclude that it is possible to discriminate samples that contain different kinds of fiber using ATR-FTIR. [ABSTRACT FROM AUTHOR]

Abstract: A pilot project aimed at testing roe enhancement strategies based on offshore Paracentrotus lividus cultures was conducted off the south‐east coast of Italy (Apulia Region). Adult sea urchins were reared in sea cages located 700 m offshore at a depth of 12 m for 3 months. The animals were fed once a week on two formulated diets, prepared mixing nutrients with agar 20 g/Kg and differing only in terms of the protein source: anchovy flour (Diet A) or krill flour (Diet K). At the end of the rearing trial, the gonad somatic index of sea urchins fed on formulated diets significantly exceeded that of wild sea urchins. Total FAA content in the gonads of wild sea urchins and Diet A‐fed sea urchins was similar, whereas in Diet K‐fed sea urchins it was significantly higher. In terms of fatty acids, the gonads contained SFAs, MUFAs and PUFAs. In visual and sensory assessment of gonads by panel test and electronic nose, the gonads of reared sea urchins were rated as being of better size, while no differences were recorded for coloration, taste and odour. This study shows that under these experimental conditions, commercial‐grade Paracentrotus lividus roe enhancement can be achieved after 3 months in sea cages. [ABSTRACT FROM AUTHOR]

Satellite cells are adult stem cells located between the basal lamina and sarcolemma of muscle fibers. Under physiological conditions, satellite cells are quiescent, but they maintain a strong proliferative potential and propensity to differentiate, which underlies their critical role in muscle preservation and growth. MicroRNAs (miRNAs) play essential roles during animal development as well as in stem cell self-renewal and differentiation regulation. MiRNA-1, miRNA-133a and miRNA-206 are closely related muscle-specific miRNAs, and are thus defined myomiRNAs. MyomiRNAs are integrated into myogenic regulatory networks. Their expression is under the transcriptional and post-transcriptional control of myogenic factors and, in turn, they exhibit widespread control of muscle gene expression. Very little information is available about the regulation and behavior of satellite cells in large farm animals, in particular during satellite cell differentiation. Here, we study bovine satellite cells (BoSCs) undergoing a differentiation process and report the expression pattern of selected genes and miRNAs involved. Muscle samples of longissimus thoracis from Holstein adult male animals were selected for the collection of satellite cells. All satellite cell preparations demonstrated myotube differentiation. To characterize the dynamics of several transcription factors expressed in BoSCs, we performed real-time PCR on complementary DNA generated from the total RNA extracted from BoSCs cultivated in growth medium (GM) or in differentiation medium (DM) for 4 days. In the GM condition, BoSCs expressed the satellite cell lineage markers as well as transcripts for the myogenic regulatory factors. At the time of isolation from muscle, PAX7 was expressed in nearly 100% of BoSCs; however, its messenger RNA (mRNA) levels dramatically decreased between 3 and 6 days post isolation ( P<0.01). MyoD mRNA levels increased during the 1st day of cultivation in DM (day 7; P<0.02), showing a gradual activation of the myogenic gene program. During the subsequent 4 days of culture in DM, several tested genes, including MRF4, MYOG, MEF2C, TMEM8C, DES and MYH1, showed increased expression ( P<0.05), and these levels remained high throughout the culture period investigated. Meanwhile, the expression of genes involved in the differentiation process also miRNA-1, miRNA-133a and miRNA-206 were strongly up-regulated on the 1st day in DM (day 7; P<0.05). Analysis revealed highly significant correlations between myomiRNAs expression and MEF2C, MRF4, TMEM8C, DES and MYH1 gene expression ( P<0.001). Knowledge about the transcriptional changes correlating with the growth and differentiation of skeletal muscle fibers could be helpful for developing strategies to improve production performance in livestock. [ABSTRACT FROM AUTHOR]

A field trial conducted on the melon cultivar Huanghemi irrigated with saline water was carried out in Minqin County in the 2-year period, 2007 and 2008. In three irrigation treatments, different saline water concentrations were applied, that is 0.8 g l−1 (Control C), 2 g l−1 (Treatment S1) and 5 g l−1 (Treatment S2), reproducing the natural groundwater concentration in the county. The electrical conductivity of the saline water was as follows: 1.00, 2.66 and 7.03 dS m−1, respectively. The aims of the study were (i) to monitor water consumption and water potential, (ii) assess, during the whole crop cycle, some growth parameters and their relations for estimating the morpho-functional plant response irrigated with saline water and (iii) determine the ion concentration in different plant tissues to evaluate which mechanism the plant activates in the presence of high salt concentrations. Under salinity stress, the plants sustained the concentration of Ca, Mg and K, but at a level not sufficient to limit the Na adsorption. Therefore, the melon yield decreased and it was determined by a displacement of the ratio K/Na and by a lower [ABSTRACT FROM AUTHOR]

Epithelial cells are shed into milk during lactation, and although they generally reflect the cellular charcteristics of terminally differentiated luminal cells, previously the detection of more primitive cells was described in human milk where a cell population of epithelial lineage was detected expressing markers typical of progenitor cells. In this investigation, we report the development of flow cytometry analysis to allow mul-tiparametric assessment of mammary epithelial cells observed in milk. Cells collected from milk samples of 10 healthy dairy cows were directly analyzed for 6 different markers: CD45, CD49f, cytokeratin 14, cyto-keratin 18, presence of nucleus, and cell viability. Milk samples were collected in 3 different periods of lactation: early lactation (EL = d 0-30), mid-lactation (ML = d 90-120), and late lactation (LL = 210-250). Here we identify the differential expression of precursor or differentiated cell markers (or both) in mammary epithelial cells present in bovine milk. Myoepithelial cells, as indicated by cells staining positively for cytokeratin 14+/cytokeratin 18-, were observed to increase from EL to LL with a high correlation with nuclear staining inferring potential proliferative activity. Furthermore, a significant increase in CD49f+ and cytokeratin 14+/cy-tokeratin 18+ positive cells was observed in LL. This assay is a sensitive approach for evaluating the variations in the frequency and features of living epithelial cells, whose reciprocal balance may be significant in understanding mammary gland cellular function throughout lactation. These observations suggest that mammary epithelial cell immunophenotypes could be investigated as biomarkers for mammary gland function in dairy cows. [ABSTRACT FROM AUTHOR]

Context. Planetary nebulae (PNe) are powerful tracers of evolved stellar populations. Among the 3000 known PNe in the Galaxy, about 600 are located within the 520 square-degree area covered by the VVV survey. The VVV photometric catalogue provides an important new dataset for the study of PNe, with high-resolution imaging in five near-infrared bands. Aims. There are various colour-colour diagrams that can be obtained from the VVV filters. We investigate the location of PNe in these diagrams and the separation from other types of objects. This includes the new Y-J vs. Z-Y diagram. Methods. Aperture photometry of known PNe in the VVV area was retrieved from source catalogues. Care was taken to minimise any confusion with field stars. The colours of the PNe we are determined for (H-Ks), (J-H), (Z-Y), and (Y-J), and compared to stars and to other types of emission line objects. Cloudy photo-ionisation models were used to predict colours for typical PNe. Results. We present near-infrared photometry for 353 known PNe. The best separation from other objects is obtained in the (H-Ks) vs. (J-H) diagram. We calculated the emission-line contribution to the in-band flux based on a model for NGC 6720: we find that this is highest in the Z and Y bands at over 50%, lower in the J band at 40%, and lowest in the H and Ks bands at 20%. A new view of PNe in the wavelength domain of the Z and Y bands is shown. Photo-ionisation models are used to explore the observed colours in these bands. The Y band is shown to be dominated by He i 1.083 μm and Heii 1.012 μm, and colours involving this band are very sensitive to the temperature of the ionizing star. Conclusions. The VVV survey represents a unique dataset for studying crowded and obscured regions in the Galactic plane. The diagnostic diagrams presented here allow one to study the properties of known PNe and to uncover objects not previously classified. [ABSTRACT FROM AUTHOR]

The algal polysaccharide agar has long been used as a food binder due to its structure, rheological behaviour, stability and interactions - properties that help to generate firm, round, disk-shaped pellets that may be used in recirculating sea urchin-rearing systems. Three algae-based diets ( Ulva lactuca, Gracilaria gracilis, Cystoseira sp.) containing 3% and 6% agar were tested on the sea urchin Paracentrotus lividus in order to examine the effect of varying percentages of agar on pellet stability in water and sea urchin gonad growth. The kinetics of water absorption and solute leaching of pellets were measured by immersing quadruplicate samples of the pellets in water for 1, 2, 3, 4, 5 and 6 days. Our results show that the pellets had good water stability, were readily consumed by sea urchins and the presence of agar did not hamper sea urchin gonad growth. Animals fed Ulva-containing pellets reached a more advanced gametogenic stage with respect to animals fed Cystoseira- and Gracilaria-containing pellets. Moreover, the presence of agarase activity in the digestive system indicated that agar may be an energy source. Pellets are relatively low cost and easy to prepare and store. They may represent a useful resource for rearing sea urchins under intensive conditions. [ABSTRACT FROM AUTHOR]

The Lesina lagoon is located on the southern Adriatic coast of Italy; many marine species, such as the shrimp M. kerathurus, use the Lesina lagoon as a nursery, spending their initial growth phase there. In order to assess the usefulness of migratory species as biomonitors of the environmental quality of this nursery area, we evaluated the metal content of the M. kerathurus juveniles at the end of their growth phase in the lagoon (October), when they are assumed to have bioaccumulated the maximum level of metals from the lagoon environment. The concentrations of Cr, Cd, Pb, Zn, Mn and Cu were measured in the muscle and exoskeleton of the shrimp , and in the sediments and waters of three areas of the Lesina Lagoon. Both the water and sediment levels of the investigated metals tended to fall within the ranges recorded for other lagoon environments characterized by similar anthropic impact and texturally similar sediment; the juveniles of the shrimp M. kerathurus proved to be strong bioaccumulators of heavy metals such as Zn and Cu (biota-sediment accumulation factors – BSAFs – 6.01 and 25.0 respectively), which derive from agricultural activities; therefore, at the end of their growing phase in the lagoon they can be considered useful biomonitors of metal contamination of agricultural origin in their nursery area. [ABSTRACT FROM AUTHOR]

An innovative packaging system has been developed, based on natural gels, that has shown the peculiar characteristic to strongly increase the shelf life of water buffalo Mozzarella cheese. To explain the mechanism of action of the gel, measurements of Ca and Na in the cheese and in the storage liquid were carried out, together with pH determination. A correlation has been found between the constant level of Ca and pH in the cheese and the prolongation of nutritional characteristics; in fact, both parameters diminish significantly in the absence of gel. At the same time, the weight of the cheese in gel remained constant for as long as 30 d. Confocal laser microscopy gave direct evidence of the persistent physical structure of proteins and lipids of Mozzarella when stored in gel. [ABSTRACT FROM AUTHOR]

The innovative packaging systems described in the present work, based on natural gels, have been shown to increase the shelf life of the Mozzarella cheese, without adding any chemical substance and without thermal procedures. Physical, physicochemical, microbiological, analytical, and mechanical analyses were used to monitor the quality of the cheese as a function of storage type and storage time. In particular, microbiological analysis confirmed that the characteristics of the Mozzarella cheese stored at 4°C in gel are maintained for more than 15 d, whereas samples stored in the mother solution lost important characteristics after 5 d. A penetration test (texture) confirmed that the Mozzarella cheese preserved in the gel maintained mechanical properties similar to those of the fresh product, even after storage for 30 d at 4°C. [ABSTRACT FROM AUTHOR]

A series of biodegradable composites with natural hydroxyapatite, designed for possible use in orthopedics applications, were preliminarily screened for biocompatibility by employing primary cultures of human osteoblasts in a direct contact method. The cells were seeded at low density onto the materials under investigation and allowed to grow for 2 weeks. They then were analyzed for morphology, proliferation, viability, alkaline phosphatase activity (AP), osteocalcin (OC) production, and extracellular matrix mineralization. The results showed that all materials have good biocompatibility. Cell viability tests demonstrated that in all cases the values were comparable to the control, and the addition of hydroxyapatite always resulted in an enhancement of performance with respect to the plain polymer. AP and OC analysis confirmed that all composites allowed the expression of phenotypic markers. Scanning electron microscopy provided direct evidence of intense cell adhesion and proliferation on the tested materials., (Copyright 2001 John Wiley & Sons, Inc. J Biomed Mater Res 59: 611-617, 2002)

A new polymeric blend, polymethyl methacrylate-poly (ethylene-co-vinylacetate) (PMMA-EVA) has been produced recently in our laboratories. The optothermal characterization of PMMA-EVA was carried out by measuring the ultraviolet photoacoustic spectra of PMMA, EVA, and PMMA-EVA (25 degrees C, 220-350 nm), of a PMMA-EVA blend (250-750 nm) at two temperatures (19 degrees C and 65 degrees C), and by measuring the scattering coefficient (at 514.5 nm) of PMMA-EVA versus the temperature in the range 38-86 degrees C. Our measurements show that, in the explored thermal range, the blend undergoes a phase transition when its optical properties change drastically. The peculiar optical and thermal properties observed appear attractive for possible applications as temperature-controlled optical devices.