Characterization and probiotic potential of Lactobacillus plantarum strains isolated from cheeses

Ninety-eight Lactobacillus plantarum strains isolated from Italian and Argentinean cheeses were evaluated for probiotic potential. After a preliminary subtractive screening based on the presence of msa and bsh genes, 27 strains were characterized. In general, the selected strains showed high resistance to lysozyme, good adaptation to simulated gastric juice, and a moderate to low bile tolerance. The capacity to agglutinate yeast cells in a mannose-specific manner, as well as the cell surface hydrophobicity was found to be variable among strains. Very high β-galactosidase activity was shown by a considerable number of the tested strains, whereas variable prebiotic utilization ability was observed. Only tetracycline resistance was observed in two highly resistant strains which harbored the tetM gene, whereas none of the strains showed β-glucuronidase activity or was capable of inhibiting pathogens. Three strains (Lp790, Lp813, and Lp998) were tested by in vivo trials. A considerable heterogeneity was found among a number of L. plantarum strains screened in this study, leading to the design of multiple cultures to cooperatively link strains showing the widest range of useful traits. Among the selected strains, Lp790, Lp813, and Lp998 showed the best probiotic potential and would be promising candidates for inclusion as starter cultures for the manufacture of probiotic fermented foods.     

Synthesis,characterization, and transistor response of tetrathia-[7]-helicene precursors and derivatives

In this paper we report polycyclic, fully-conjugated, heteroaromatic compounds 1–5, two of them having a helical shape (tetrathia-[7]-helicenes 1 and 2), and explore their potential use as p-type semiconductors for organic thin-film transistors (OTFTs). Furthermore, we describe their optical absorption, emission, and electrochemical properties. In addition, the single crystal X-ray diffraction structure for compound 3 is reported. Thin films of all compounds were fabricated on several substrates at different temperatures by physical vapor deposition, and were characterized by optical spectroscopy, wide-angle X-ray diffraction, atomic force microscopy, and TFT measurements. The AFM images of compound 1 exhibit an interesting tubular morphology for films deposited at room temperature. This is the first observation of a compound with a helical shape leading to a nanowire-like morphology. In agreement with the molecular structure/morphology, only compound 4 is a p-type semiconductor with good carrier mobility.     

Metal Binding Properties of Fluorescent Analogues of Trichogin GA IV: A Conformational Study by Time‐Resolved Spectroscopy and Molecular Mechanics Investigations

The metal ion binding properties of two fluorescent analogues of trichogin GA IV, which is a natural undecapeptide showing significant antimicrobial activity, were studied by circular dichroism, time‐resolved optical spectroscopy, and molecular mechanics calculations. Binding of Ca^II and Gd^III to the peptides investigated was shown to promote a structural transition from highly helical conformations to folded structures characterized by formation of a loop that embedded the metal ion. Time‐resolved spectroscopy revealed that peptide dynamics is also remarkably affected by ion binding: peptide‐backbone motions slowed down to the microsecond time scale. Finally, molecular mechanics calculations emphasized the role of the central Gly5‐Gly6 motif, which allowed for the twisting of the peptide segment that gave rise to the formation of the binding cavity.     

Recycling of polypropylene‐based eco‐composites

BACKGROUND: Renewable resources and recyclable thermoplastic polymers provide an attractive eco‐friendly quality as well as environmental sustainability to the resulting natural fibre‐reinforced composites. The properties of polypropylene (PP)‐based composites reinforced with rice hulls or kenaf fibres were investigated with respect to their recyclability. Rice hulls from rice processing plants and natural lignocellulosic kenaf fibres from the bast of the plant Hibiscus cannabinus represent renewable sources that could be utilized for composites. Maleic anhydride‐grafted PP was used as a coupling agent to improve the interfacial adhesion between fillers and matrix. Composites containing 30 wt% reinforcement were manufactured by melt mixing and their mechanical and thermal properties were determined. The composites were then pelletized and reprocessed by melt mixing. Finally, structure/properties relationships were investigated as a function of the number of reprocessing cycles. RESULTS: It is found that the recycling processes do not induce very significant changes in flexural strength and thermal stability of the composites. In particular PP‐based composites reinforced with kenaf fibres are less sensitive to reprocessing cycles with respect to PP‐based composites reinforced with rice hulls. CONCLUSION: The response of PP‐based composites reinforced with rice hulls or kenaf fibres is promising since their properties remain almost unchanged after recycling processes. Moreover, the recycled composites are suitable for applications as construction materials for indoor applications. In fact, the flexural strength and modulus of these materials are comparable to those of conventional formaldehyde wood medium‐density fibreboards. Copyright © 2008 Society of Chemical Industry     

Nature reserve selection on forest fragments in a suburban landscape (Rome, Central Italy): indications from a set of avian species

A set of avian forest species, known from the literature as fragmentation-sensitive, was considered as the target in nature reserve planning following a conceptual framework. Their abundance was investigated in an 'archipelago' of oak woodland fragments embedded in a suburban landscape matrix of central Italy. None of the four species were found in any wood fragment smaller than 10 ha. The presence/absence analysis of woodland fragments studied showed that the study species were present, however, in larger fragments, highlighting the strategic role of habitat size and isolation for the persistence of these species at local scale. Species numbers and their total abundance were significantly and directly correlated to overall species richness of each fragment: in this landscape context our study species shows characteristics of serving as focus and surrogate species of bird richness. The selected species are area-sensitive and poor dispersers: however, they are still relatively widespread, at a regional scale. Although the abundance of individual species may be affected by stochastic factors, total abundance of this forest bird guild may constitute a useful dependent variable that can provide rapid quantitative data needed for planning strategies at local scales.     

miRNA Expression Is Increased in Serum from Patients with Semantic Variant Primary Progressive Aphasia

Primary progressive aphasia (PPA) damages the parts of the brain that control speech and language. There are three clinical PPA variants: nonfluent/agrammatic (nfvPPA), logopenic (lvPPA) and semantic (svPPA). The pathophysiology underlying PPA variants is not fully understood, including the role of micro (mi)RNAs which were previously shown to play a role in several neurodegenerative diseases. Using a two-step analysis (array and validation through real-time PCR), we investigated the miRNA expression pattern in serum from 54 PPA patients and 18 controls. In the svPPA cohort, we observed a generalized upregulation of miRNAs with miR-106b-5p and miR-133a-3p reaching statistical significance (miR-106b-5p: 2.69 ± 0.89 mean ± SD vs. 1.18 ± 0.28, p < 0.0001; miR-133a-3p: 2.09 ± 0.10 vs. 0.74 ± 0.11 mean ± SD, p = 0.0002). Conversely, in lvPPA, the majority of miRNAs were downregulated. GO enrichment and KEGG pathway analyses revealed that target genes of both miRNAs are involved in pathways potentially relevant for the pathogenesis of neurodegenerative diseases. This is the first study that investigates the expression profile of circulating miRNAs in PPA variant patients. We identified a specific miRNA expression profile in svPPA that could differentiate this pathological condition from other PPA variants. Nevertheless, these preliminary results need to be confirmed in a larger independent cohort.     

MMP-7 and fcDNA Serum Levels in Early NSCLC and Idiopathic Interstitial Pneumonia: Preliminary Study

A non-invasive test to facilitate the diagnosis of non-small cell lung cancer (NSCLC) and idiopathic pulmonary fibrosis (IPF) is still not available and represents an important goal. Forty-eight patients with stage I NSCLC, 45 with IPF, 30 with other idiopathic interstitial pneumonias (IIPs) including idiopathic non-specific interstitial pneumonia (NSIP) and chronic hypersensitivity pneumonitis (HP), 35 with diffuse non-malignant disease and 30 healthy donors were enrolled onto the study. Free circulating (fc)DNA and MMP-7 levels were evaluated by Real Time PCR and ELISA, respectively. Median fcDNA levels were similar in NSCLC (127 ng/mL, range 23.6–345 ng/mL) and IPF (106 ng/mL, range 22–224 ng/mL) patients, and significantly lower in IIPs patients, in individuals with other diseases and in healthy donors (p < 0.05). Conversely, median MMP-7 values were significantly higher in IPF patients (9.10 ng/mL, range 3.88–19.72 ng/mL) than in those with NSCLC (6.31 ng/mL, range 3.38–16.36 ng/mL; p < 0.0001), NSIP (6.50 ng/mL, range 1.50–22.47 ng/mL; p = 0.007), other diseases (5.41 ng/mL, range 1.78–15.91, p < 0.0001) or healthy donors (4.35 ng/mL, range 2.45–7.23; p < 0.0001). Serum MMP-7 levels seem to be capable of distinguishing IPF patients from those with any other lung disease. fcDNA levels were similar in NSCLC and IPF patients, confirming its potential role as a biomarker, albeit non-specific, for the differential diagnosis of NSCLC.     

Peripheral Blood miR-328 Expression as a Potential Biomarker for the Early Diagnosis of NSCLC

Lung cancer is often diagnosed at an advanced stage, with subsequently poor prognosis. There are no biomarkers available to facilitate early diagnosis or to discriminate between benign and malignant nodules. MicroRNAs (miRNAs) are stable molecules that can be found and measured in peripheral blood, thus representing potential diagnostic biomarkers. We evaluated 100 individuals comprising 86 patients with predominantly early-stage non-small cell lung cancer (NSCLC) and 24 healthy donors. RNA was extracted from peripheral blood samples and the expression of a panel of miRNAs was analyzed by Real-Time PCR method. Expression levels of miR-328, miR-18a, miR-339 and miR-140 were significantly higher in NSCLC patients than in healthy donors (p < 0.05). In particular, miR-328 showed good diagnostic accuracy in discriminating between patients with early NSCLC and healthy donors (AUC ROC 0.82, 95% CI 0.72–0.92), with 70% sensitivity and 83% specificity at the best relative expression cut-off of 300. Moreover, miR-339 was a good discriminant between healthy donors and late-stage NSCLC patients (AUC ROC 0.79, 95% CI 0.68–0.91). In conclusion, miR-328 represents a potential diagnostic biomarker of NSCLC, especially for the identification of early-stage tumors. Its role in discriminating between benign and malignant nodules detected by spiral CT warrants further investigation.