The state of oxygenation of haemoglobin in the blood of living Tubifex (Annelida)

Spectroscopic observations of the blood of the living worm have been made using various gas mixtures. The state of oxygenation of the blood has been determined particularly at the critical level where the respiration changes from an independent to a dependent type.
Oxygen dissociation curves have been plotted using gas mixtures with 0.03% carbon dioxide and 5% carbon dioxide at three temperatures to correlate the in vivo and in vitro states of oxygenation with the normal environment in which the animal lives.     

Discovery of XL888: A novel tropane-derived small molecule inhibitor of HSP90

With structural guidance, tropane-derived HTS hits were modified to optimize for HSP90 inhibition and a desirable in vivo profile. Through an iterative SAR development process 12i (XL888) was discovered and shown to reduce HSP90 client protein content in PD studies. Furthermore, efficacy experiments performed in a NCI-N87 mouse xenograft model demonstrated tumor regression in some dosing regimens.     

Long-term daily access to alcohol alters dopamine-related synthesis and signaling proteins in the rat striatum

Chronic alcohol exposure can adversely affect neuronal morphology, synaptic architecture and associated neuroplasticity. However, the effects of moderate levels of long-term alcohol intake on the brain are a matter of debate. The current study used 2-DE (two-dimensional gel electrophoresis) proteomics to examine proteomic changes in the striatum of male Wistar rats after 8 months of continuous access to a standard off-the-shelf beer in their home cages. Alcohol intake under group-housed conditions during this time was around 3–4 g/kg/day, a level below that known to induce physical dependence in rats. After 8 months of access rats were euthanased and 2-DE proteomic analysis of the striatum was conducted. A total of 28 striatal proteins were significantly altered in the beer drinking rats relative to controls. Strikingly, many of these were dopamine (DA)-related proteins, including tyrosine hydroxylase (an enzyme of DA biosynthesis), pyridoxal phosphate phosphatase (a co-enzyme in DA biosynthesis), DA and cAMP regulating phosphoprotein (a regulator of DA receptors and transporters), protein phosphatase 1 (a signaling protein) and nitric oxide synthase (which modulates DA uptake). Selected protein expression changes were verified using Western blotting. We conclude that long-term moderate alcohol consumption is associated with substantial alterations in the rat striatal proteome, particularly with regard to dopaminergic signaling pathways. This provides potentially important evidence of major neuroadaptations in dopamine systems with daily alcohol consumption at relatively modest levels.     

Seasonal modulation of plasma antifreeze protein levels in Atlantic (Anarhichas lupus) and spotted wolffish (A. minor)

The Atlantic and spotted wolffish (Anarhichas lupus and A. minor, respectively) inhabit the cold waters of the northeast Atlantic Ocean. Although both species experience subzero water temperatures during winter, the Atlantic wolffish, which occupies shallower waters than the spotted wolffish, faces the greater threat of coming into contact with ice and freezing. This laboratory study was designed to determine whether these species differed in their abilities to resist freezing by examining the seasonal changes in blood plasma freezing points, antifreeze protein (AFP) activity and Na⁺ and Cl⁻ concentrations when exposed to seasonally cycling water temperatures and photoperiod. The plasma of both species showed distinct seasonal cycles in all parameters with the highest values occurring during the winter. However, of the two species, only the Atlantic wolffish produced sufficient AFP to protect the fish down to the freezing point of seawater (− 1.80 °C). The levels of AFP in the spotted wolffish were too low to impart any significant improvement in their resistance to freezing (approximately − 0.8 °C).When wolffish were maintained in warm water under a seasonally changing photoperiod, the amplitude of the seasonal cycle in AFP activity was greatly reduced, indicating that low water temperatures are necessary to maximize plasma AFP levels. However, despite being maintained in warm water, plasma levels of AFP activity began to increase over summer values at the same time of year as did the fish exposed to seasonally changing water temperatures. This suggests that photoperiod plays a major role in the timing of the annual AFP cycle.     

The combined CTA1-DD/ISCOM adjuvant vector promotes priming of mucosal and systemic immunity to incorporated antigens by specific targeting of B cells

The cholera toxin A1 (CTA1)-DD/QuilA-containing, immune-stimulating complex (ISCOM) vector is a rationally designed mucosal adjuvant that greatly potentiates humoral and cellular immune responses. It was developed to incorporate the distinctive properties of either adjuvant alone in a combination that exerted additive enhancing effects on mucosal immune responses. In this study we demonstrate that CTA1-DD and an unrelated Ag can be incorporated together into the ISCOM, resulting in greatly augmented immunogenicity of the Ag. To demonstrate its relevance for protection against infectious diseases, we tested the vector incorporating PR8 Ag from the influenza virus. After intranasal immunization we found that the immunogenicity of the PR8 proteins were significantly augmented by a mechanism that was enzyme dependent, because the presence of the enzymatically inactive CTA1R7K-DD mutant largely failed to enhance the response over that seen with ISCOMs alone. The combined vector was a highly effective enhancer of a broad range of immune responses, including specific serum Abs and balanced Th1 and Th2 CD4(+) T cell priming as well as a strong mucosal IgA response. Unlike unmodified ISCOMs, Ag incorporated into the combined vector could be presented by B cells in vitro and in vivo as well as by dendritic cells; it also accumulated in B cell follicles of draining lymph nodes when given s.c. and stimulated much enhanced germinal center reactions. Strikingly, the enhanced adjuvant activity of the combined vector was absent in B cell-deficient mice, supporting the idea that B cells are important for the adjuvant effects of the combined CTA1-DD/ISCOM vector.     

Phenotypic characterization of Streptococcus pneumoniae biofilm development

Streptococcus pneumoniae is among the most common pathogens associated with chronic otitis media with effusion, which has been hypothesized to be a biofilm disease. S. pneumoniae has been shown to form biofilms, however, little is known about the developmental process, the architecture, and the changes that occur upon biofilm development. In the current study we made use of a continuous-culture biofilm system to characterize biofilm development of 14 different S. pneumoniae strains representing at least 10 unique serotypes. The biofilm development process was found to occur in three distinct stages, including initial attachment, cluster formation, and biofilm maturation. While all 14 pneumococcal strains displayed similar developmental stages, the mature biofilm architecture differed significantly among the serotypes tested. Overall, three biofilm architectural groups were detected based on biomass, biofilm thickness, and cluster size. The biofilm viable cell counts and total protein concentration increased steadily over the course of biofilm development, reaching approximately 8 x 10(8) cells and approximately 15 mg of protein per biofilm after 9 days of biofilm growth. Proteomic analysis confirmed the presence of distinct biofilm developmental stages by the detection of multiple phenotypes over the course of biofilm development. The biofilm development process was found to correlate not only with differential production of proteins but also with a dramatic increase in the number of detectable proteins, indicating that biofilm formation by S. pneumoniae may be a far more complex process than previously anticipated. Protein identification revealed that proteins involved in virulence, adhesion, and resistance were more abundant under biofilm growth conditions. A possible role of the identified proteins in biofilm formation is discussed.