ACTH Induced Behaviors and their Modulation by Serotonergic Agonists differ in Neonatal and Weanling Rat Pups

Four-day-old (P4) and 21–22-day-old (P21–22) rat pups received an intracisternal injection of either ACTH1-16NH2 or saline followed by a subcutaneous (SC) injection of saline, the serotonergic (5HT)1A agonists 8-OH-DPAT or ipsapirone, the 5HT1B agonist TFMPP or the 5HT2 agonist DOI. The ontogeny of ACTH-induced behaviors including grooming, yawn and stretch as well as various serotonin-related behaviors were recorded via time-sampling at 20 s intervals for a test duration of 50 min. ACTH induced slight but significant increases in grooming at P4, along with a significant increase in yawning. At this age the 5HT1B agonist TFMPP induced substantial increases in grooming, with no effect of the other agonists on this behavior. All of the serotonergic agonists, however, decreased ACTH-induced yawning at P4. At P21–22 ACTH induced more robust grooming than that observed at P4, although different in nature from adult-typical ACTH-induced grooming. This ACTH-induced grooming at P21–22 was attenuated by all of the serotonergic agonists. ACTH-induced yawning at P21–22 was not affected by the serotonergic agonists while ACTH-induced stretching was increased by the 5HT1B agonist TFMPP at this age. These data provide additional evidence of differential mediation of various ACTH-induced behaviors, and support other reports of ontogenetic alterations in the response to serotonergic manipulations during the neonatal to weanling age period

Investigation of the multifaceted iron acquisition strategies of Burkholderia cenocepacia

Burkholderia cenocepacia is a bacterial pathogen which causes severe respiratory infections in cystic fibrosis (CF). These studies were aimed at gaining an insight into the iron acquisition strategies of B. cenocepacia. In iron restricted conditions, genes associated with the synthesis and utilisation of ornibactin (pvdA, orbA, orb F) were significantly upregulated compared to the expression of pyochelin associated genes (pchD, fptA). In the absence of alternative iron sources, B. cenocepacia J2315 and 715j utilised ferritin and haemin, but not transferrin or lactoferrin for growth. Significantly, mutants unable to produce ornibactin, (715j-orbI) or ornibactin and pyochelin, (715j-pobA), utilised haemin and ferritin more efficiently than the wild-type. Moreover, both mutants were also able to utilise lactoferrin for growth (P ≤ 0.01) and additionally 715j-pobA utilised transferrin (P ≤ 0.01), potentially facilitating adaptation to the host environment. Furthermore, B. cenocepacia increased ornibactin gene expression in response to pyoverdine from Pseudomonas aeruginosa (P ≤ 0.01), demonstrating the capacity to compete for iron in co-colonised niches. Pyoverdine also significantly diminished the growth of B. cenocepacia (P < 0.001) which was related to its iron chelating activity. In a study of three B. cenocepacia sequential clonal isolates obtained from a CF patient over a 3.5 year period, ornibactin upregulation in response to pyoverdine was less pronounced in the last isolate compared to the earlier isolates, as was growth in the presence of haemin and ferritin, indicating alternative iron acquisition mechanism(s) may dominate as chronic infection progresses. These data demonstrate the multifaceted iron acquisition strategies of B. cenocepacia and their capacity to be differentially activated in the presence of P. aeruginosa and during chronic infection

Institutionalizing Ethics in Institutional Voids: Building Positive Ethical Strength to Serve Women Microfinance Borrowers in Negative Contexts

This study examines whether microfinance institutions (MFIs) that serve women borrowers at the base of the economic pyramid are likely to adopt a written code of positive organizational ethics (POE). Using econometric analysis of operational and economic data of a sample of MFIs from across the world, we find that two contextual factors—poverty level and lack of women’s empowerment—moderate the influence of an MFI’s percentage of women borrowers on the probability of the MFI having a POE code. MFIs that serve more women borrowers are more likely to adopt a POE code, especially in negative contexts (where women borrowers face poverty and disempowerment and are therefore susceptible to abuse). This study provides evidence that MFIs can build positive ethical strength in negative contexts