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Lectins were used to characterize glycoconjugates on the cell surface of Treponema denticola, a suspected periodontopathogen. Bacteria were first screened by light microscopy using fluorescein isothiocyanate-coupled lectins. Wheat germ agglutinin (WGA) showed a high reactivity to T. denticola. While the WGA-binding activity was accentuated following heating or detergent treatments of bacterial cells, the reaction was inhibited by incorporation of competing carbohydrates. Scanning and transmission electron microscope studies were conducted in order to characterize the distribution of the WGA-binding sites on the cell surface of T. denticola. Data from these studies confirmed that heat treatment increases the percentage of labeled profiles and suggest that the WGA-binding sites are concentrated on specific regions on the spirochete surface. Initial biochemical analysis indicated that the high reactivity to WGA resides in a peptidoglycan fraction. [ABSTRACT FROM AUTHOR]

The Baby-Friendly Hospital Initiative (BFI) is currently presented worldwide as the gold standard model of care for promoting and supporting breastfeeding. However, there is a lack of understanding about the ways in which health services, including the BFI, address the cultural change from a disembodied practice (formula feeding) to an embodied one (breastfeeding) in contexts where formula feeding is the norm. We used a qualitative case study methodology to compare the embodied experience of breastfeeding and the maternal experience of breastfeeding promotion and support services between mothers receiving care from institutions with low and high levels of BFI implementation in Québec, Canada. A total of 11 focus groups were conducted with mothers from six institutions-three with high and three with low levels of BFI implementation. We found the flexible approach to breastfeeding duration, characteristic of BFI services in our study, helped to avoid maternal guilt and shame; the shift to focusing on potential barriers and strategies for overcoming them empowered women to negotiate changes in infant feeding with others and self by addressing the embodied experience of a practice that may not feel natural at the beginning. Findings have implications for the concept of habitus and the construction of the breastfeeding body; we suggest that habitus can change if agents are provided with discursive tools to negotiate this embodied change. Implications for BFI services include the need to implement the 10 steps in a flexible, family-centred way that focuses on empowering women rather than simply reaching outcomes., (© 2016 John Wiley & Sons Ltd.)

This study focuses on Brazilian mothers who gave birth to premature babies who were discharged from hospital using the Kangaroo Mother Care Method. While mothers left the hospital breastfeeding exclusively, once back at home, they abandoned exclusive breastfeeding because of insufficient breast milk (IBM). In this project we explored how IBM was interpreted by mothers within their social context. Participatory research using the Creative Sensitive Method was done in the homes of mothers with family members and neighbours. We described the conflicting social discourse that influenced the mothers' perception of IBM and explored their sources of distress. At the hospital and Kangaroo ward, mothers considered that clinicians recognized they were experiencing IBM and thus supported them to overcome this problem. Back at home and in their community, other sources of stress generated anxiety such as: the lack of outpatient clinical support, and conflicting local norms to care and feed premature babies. These difficulties combined with economic constraints and discontinuity in models of health care led mothers to lose confidence in their breastfeeding capacity. Mothers, thus, rapidly replaced exclusive breastfeeding by mixed feeding or formula feeding. Our analysis suggests that IBM in our sample was the result of a socio-somatic process. Recommendations are proposed to help overcome IBM and corresponding contextual barriers to exclusive breastfeeding.

The bacteriocin pediocin PA-1 produced by Pediococcus acidilactici PAC 1.0 offers significant potential as a food preservative and as an antimicrobial agent in the medical area. However, low production yields and difficulties in obtaining significant amounts of pure pediocin PA-1 have limited, in part, its biochemical and physical characterization. In the present study, we describe a simple and more efficient purification strategy for pediocin PA-1. A hydrophobic interaction chromatography step using an octyl-Sepharose column was introduced for final purification and polishing. The new method is a scalable one, uses only two steps and yields highly purified pediocin PA-1 with a recovery as high as 73%, which is at least two to three times more than that of the methods reported so far. Highly purified, biologically active pediocin PA-1 of the correct molecular mass (4624 Da, with two disulphide bridges) was obtained. Fourier-transform infrared analysis runs at p2H 6 indicated that pediocin PA-1 was more structured than similar pediocin PA-1 samples purified using the earlier purification scheme.

Fluorescence spectra of a 4-hydroxy-2(or 5)-ethyl-5(or 2)-methyl-3(2H)-furanone (HEMF) fermentation culture broth were combined with measurable process variables for off-line and on-line process monitoring. Culture broth fluorescence in UV and visible ranges was acquired by a fiber optic LCD array spectrometer. Process dynamics was followed on-line using a fiber optic probe attached to an external recirculation loop of the bioreactor. Partial least squares and stepwise regression methods were used to correlate measurable process parameters with the components of the fluorescence spectra. Both methods provided adequate approximation of yeast density, HEMF, glucose, and ethanol concentrations from fluorescence spectra. HEMF production was observed during the oxido-reductive growth phase when there was a lack of measurable oxygen in the culture broth and an excess of glucose. The addition of glucose resulted in the rapid production of HEMF and other metabolite intermediates such as ethanol, acetate, and glycerol.

Lectins were used to characterize glycoconjugates on the cell surface of Treponema denticola, a suspected periodontopathogen. Bacteria were first screened by light microscopy using fluorescein isothiocyanate-coupled lectins. Wheat germ agglutinin (WGA) showed a high reactivity to T. denticola. While the WGA-binding activity was accentuated following heating or detergent treatments of bacterial cells, the reaction was inhibited by incorporation of competing carbohydrates. Scanning and transmission electron microscope studies were conducted in order to characterize the distribution of the WGA-binding sites on the cell surface of T. denticola. Data from these studies confirmed that heat treatment increases the percentage of labeled profiles and suggest that the WGA-binding sites are concentrated on specific regions on the spirochete surface. Initial biochemical analysis indicated that the high reactivity to WGA resides in a peptidoglycan fraction.

Rhodococcus ATCC 39484 produced a nitrilase when induced with isovaleronitrile. The enzyme was obtainable pure in milligram amounts, had a subunit Mr of 40 kDa, and demonstrated a substrate-induced activation related to aggregation of subunits to form a 560-kDa complex. The enzyme had a broad substrate specificity, had a pH optimum of 7.5, was stable up to 40 degrees C, and had one disulfide bridge and two free cysteine residues, one of which appeared to be catalytically essential. The N-terminal sequence was determined and found to have 78.3% homology, in a 23-residue overlap, with Klebsiella ozaenae nitrilase. The enzyme was inhibited competitively by benzylamine and benzaldehyde and irreversibly by benzyl bromide. However, benzyl bromide was shown to be nonspecific, causing multiple alkylation. Acid quenching of enzyme-substrate mixtures allowed for the detection of covalent enzyme-substrate complexes using mass spectrometry. The covalent intermediate is suggested to be either a thioimidate or an acylenzyme and a reaction mechanism consistent with this observation and also the inhibitor results is proposed. The rate of breakdown of the covalent intermediates was found to be rate limiting even for substrates with undetectable rates of hydrolysis or those with very slow rates of intermediate formation. For phenylacetonitrile, a poor substrate, in addition to acid, approximately 2% of the product was the corresponding amide. This result suggests that a tetrahedral intermediate is formed which, for selected substrates, can break down anomalously to produce amide in place of the normal acid product. Under the conditions used in this study all other substrates tested were converted to acid.