165 research outputs found

    Proteomic expression profiling of Haemophilus influenzae grown in pooled human sputum from adults with chronic obstructive pulmonary disease reveal antioxidant and stress responses

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Nontypeable <it>Haemophilus influenzae </it>colonizes and infects the airways of adults with chronic obstructive pulmonary disease, the fourth most common cause of death worldwide.Thus, <it>H. influenzae</it>, an exclusively human pathogen, has adapted to survive in the hostile environment of the human airways.To characterize proteins expressed by <it>H. influenzae </it>in the airways, a prototype strain was grown in pooled human sputum to simulate conditions in the human respiratory tract.The proteins from whole bacterial cell lysates were solubilized with a strong buffer and then quantitatively cleaned with an optimized precipitation/on-pellet enzymatic digestion procedure.Proteomic profiling was accomplished by Nano-flow liquid chromatography/mass spectroscopy with low void volume and high separation efficiency with a shallow, long gradient.</p> <p>Results</p> <p>A total of 1402 proteins were identified with high confidence, including 170 proteins that were encoded by genes that are annotated as conserved hypothetical proteins.Thirty-one proteins were present in greater abundance in sputum-grown conditions at a ratio of > 1.5 compared to chemically defined media.These included 8 anti-oxidant and 5 stress-related proteins, suggesting that expression of antioxidant activity and stress responses is important for survival in the airways.Four proteins involved in uptake of divalent anions and 9 proteins that function in uptake of various molecules were present in greater abundance in sputum-grown conditions.</p> <p>Conclusions</p> <p>Proteomic expression profiling of <it>H. influenzae </it>grown in pooled human sputum revealed increased expression of antioxidant, stress-response proteins and cofactor and nutrient uptake systems compared to media grown cells.These observations suggest that <it>H. influenzae </it>adapts to the oxidative and nutritionally limited conditions of the airways in adults with chronic obstructive pulmonary disease by increasing expression of molecules necessary for survival in these conditions.</p

    Horizontally acquired glycosyltransferase operons drive salmonellae lipopolysaccharide diversity.

    Get PDF
    The immunodominant lipopolysaccharide is a key antigenic factor for Gram-negative pathogens such as salmonellae where it plays key roles in host adaptation, virulence, immune evasion, and persistence. Variation in the lipopolysaccharide is also the major differentiating factor that is used to classify Salmonella into over 2600 serovars as part of the Kaufmann-White scheme. While lipopolysaccharide diversity is generally associated with sequence variation in the lipopolysaccharide biosynthesis operon, extraneous genetic factors such as those encoded by the glucosyltransferase (gtr) operons provide further structural heterogeneity by adding additional sugars onto the O-antigen component of the lipopolysaccharide. Here we identify and examine the O-antigen modifying glucosyltransferase genes from the genomes of Salmonella enterica and Salmonella bongori serovars. We show that Salmonella generally carries between 1 and 4 gtr operons that we have classified into 10 families on the basis of gtrC sequence with apparent O-antigen modification detected for five of these families. The gtr operons localize to bacteriophage-associated genomic regions and exhibit a dynamic evolutionary history driven by recombination and gene shuffling events leading to new gene combinations. Furthermore, evidence of Dam- and OxyR-dependent phase variation of gtr gene expression was identified within eight gtr families. Thus, as O-antigen modification generates significant intra- and inter-strain phenotypic diversity, gtr-mediated modification is fundamental in assessing Salmonella strain variability. This will inform appropriate vaccine and diagnostic approaches, in addition to contributing to our understanding of host-pathogen interactions

    The Butterfly Fauna Of The Italian Maritime Alps:Results Of The &#171;Edit&#187; Project

    Get PDF
    Bonelli, Simona, Barbero, Francesca, Casacci, Luca Pietro, Cerrato, Cristiana, Balletto, Emilio (2015): The butterfly fauna of the Italian Maritime Alps: results of the EDIT project. Zoosystema 37 (1): 139-167, DOI: 10.5252/z2015n1a6, URL: http://dx.doi.org/10.5252/z2015n1a

    The default-mode, ego-functions and free-energy: a neurobiological account of Freudian ideas

    Get PDF
    This article explores the notion that Freudian constructs may have neurobiological substrates. Specifically, we propose that Freud’s descriptions of the primary and secondary processes are consistent with self-organized activity in hierarchical cortical systems and that his descriptions of the ego are consistent with the functions of the default-mode and its reciprocal exchanges with subordinate brain systems. This neurobiological account rests on a view of the brain as a hierarchical inference or Helmholtz machine. In this view, large-scale intrinsic networks occupy supraordinate levels of hierarchical brain systems that try to optimize their representation of the sensorium. This optimization has been formulated as minimizing a free-energy; a process that is formally similar to the treatment of energy in Freudian formulations. We substantiate this synthesis by showing that Freud’s descriptions of the primary process are consistent with the phenomenology and neurophysiology of rapid eye movement sleep, the early and acute psychotic state, the aura of temporal lobe epilepsy and hallucinogenic drug states

    Expéditions polaires françaises (Missions P. E. Victor), Zoologie. 5e note

    No full text
    Lesse Hubert de, Strenzke R., Thienemann A. Expéditions polaires françaises (Missions P. E. Victor), Zoologie. 5e note. In: Bulletin de la Société entomologique de France, volume 56 (4), avril 1951. pp. 53-55

    Data base for district heating pipe system design

    No full text
    A methodology and data base for assigning installation costs and length requirements of hot water pipes for district heat service are described. These variables are the most important elements in the cost of the distribution system. The assignment technique is applicable to any city and reflects such factors as land use intensity, congestion of present underground service lines, and local labor rates and materials procurement costs

    Entropy models with entropy constraints on aggregated events

    No full text
    Most spatial models deal with a number of objects, such as segments of demand, as well as supply choices including houses, jobs, transport modes or routes, etc. A choice of or by any of these objects represents a probabilistic event (decision step). The problem is to determine the joint probability density for the collection of events. In this paper, the joint probability function is estimated using an extended entropy model, constrained by additional information on the entropy of aggregated events. The resulting models are compared with existing formulations, based either on entropy maximization or on utility maximization. It is also shown that models which are used for predicting demand can be generalized to allow for the dependence of demand on supply, allowing for nonhomogeneous zonal supply and supply - demand imbalances.
    corecore