HLA and NK cell inhibitory receptor genes in resolving hepatitis C virus infection

Natural killer (NK) cells provide a central defense against viral infection by using inhibitory and activation receptors for major histocompatibility complex class I molecules as a means of controlling their activity. We show that genes encoding the inhibitory NK cell receptor KIR2DL3 and its human leukocyte antigen C group 1 (HLA-C1) ligand directly influence resolution of hepatitis C virus (HCV) infection. This effect was observed in Caucasians and African Americans with expected low infectious doses of HCV but not in those with high-dose exposure, in whom the innate immune response is likely overwhelmed. The data strongly suggest that inhibitory NK cell interactions are important in determining antiviral immunity and that diminished inhibitory responses confer protection against HCV.     

Characterization of odor-active compounds in extracts obtained by simultaneous extraction/distillation from moroccan black olives

"Greek-style" Moroccan black table olives were screened for potent odorants by GC/olfactometry/aroma extract dilution analysis of representative Likens-Nickerson extracts and compared with "Spanish-style" green fruits. ( Z)-3-Hexenal, ( E, E)-2,4-decadienal, ( E, Z)-2,4-decadienal, guaiacol, and methional were found in both green and black olives, but with significant differences in concentration according to the fruit ripening degree (the first was lower and the last two were higher in black fruits). Specific compounds not previously detected in green olives (gamma-deca- and dodecalactones, delta-decalactone, and 2-methyl-3-furanthiol) proved to be, with methional, the strongest odors in black olive extracts. These extracts were also distinguishable from green olive extracts by the presence of new sulfur compounds and fewer terpenes.     

Habitat disruption and the identification and management of functional trait changes

Aquatic ecosystems are facing escalating threats from urbanization, habitat loss and projected impacts of climate change, which both individually and in combination have the potential to fundamentally alter ecosystem functioning. While it is well established that habitat disturbances can affect the composition and diversity of aquatic communities, only recently have studies considered whether such impacts result in changes in species’ functional traits. We consider how functional traits of freshwater and marine fishes respond to environmental change, and how shifts in the expression of these traits can impact community dynamics and key ecological processes, including trophic interactions and nutrient transfer. We find that a multitude of functional traits, including behavioural and sensory traits, is sensitive to habitat disturbances. We demonstrate how these trait changes can be used to reveal hidden “ecological diversity” as well as serving as early indicators of environmental perturbation. We conclude that management strategies that consider the fundamental biological responses of fishes to habitat disturbance will be particularly effective in determining causal relationships within the ecological network. While detailed information on trait function is often lacking, even some general understanding of trait function and importance will facilitate targeted and efficient ecosystem management. We urge fisheries biologists and aquatic ecosystem managers to consider the role of functional traits in facilitating effective habitat restoration and management.     

Release of deuterated nonenal during beer aging from labeled precursors synthesized in the boiling kettle.

The use of labeled nonenal enabled the demonstration that the appearance of the cardboard flavor in finished beer comes from lipid auto-oxidation during wort boiling and not from lipoxygenasic activity during mashing. Free trans-2-nonenal produced by linoleic acid auto-oxidation in the kettle disappears, owing to retention by wort amino acids and proteins. This binding linkage protects trans-2-nonenal from yeast reduction but is reversible, allowing release of the compound at lower pH during aging. Labeled trans-2-nonenal is detected after aging when deuterated precursors form in the boiling kettle. The amount of alkenal released correlates with the concentration of reversible associations in the pitching wort. This work brings new illumination to the formation of trans-2-nonenal and overturns many previous hypotheses. It also explains why a reduction in the beer pH intensifies the cardboard flavor.     

Polyarthritis in wild mice (Mus musculus) caused by Streptobacillus moniliformis

SUMMARY Mice trapped on farms in south-eastern Queensland had chronic abscessating osteoarthritides mainly involving the carpi and tarsi. Pleomorphic bacteria were shown by silver staining to be plentiful within lesions. Streptobacillus moniliformis was isolated from the joints, and streptobacillary polyarthritis was diagnosed. Other lesions observed included subcutaneous and hepatic abscesses.     

Selection for resistance to the herbicide imazethapyr in somaclones of soyabean

Cultivars of soyabean [ Glycine max (L.) Merr.] resistant to the herbicide imazethapyr were identified by suspending the roots of 5-day-old seedlings in nutrient culture containing 2.5 mg a.i. L^–1 imazethapyr and then comparing the inhibitory effect on root length and shoot dry weight. The four most resistant cultivars were subsequently screened as regenerating tissue cultures in a medium containing 2.0 mg a.i. L^–l imazethapyr to select somaclonal cells with increased resistance. Surviving portions of cultures were regenerated to give shoots, the plants isolated, allowed to flower and seed. These progeny were then used for further seed multiplication and seedlings from this latter generation were exposed to imazethapyr in vivo and callus and cell suspension cultures derived from these seedlings were exposed to imazethapyr in vitro . A reduction in the inhibitory effect of the imazethapyr was noted in the somaclone seedlings and tissue cultures. However, measurement of acetolactate synthase (ALS) activity showed no differences among the parent cultivars and in the selected somaclones in this trait.     

Detecting benzimidazole resistance with faecal egg count reduction tests and in vitro assays

Composite strains of Trichostrongylus colubriformis and Ostertagia spp consisting of 0, 1, 10, 25, 50, 75, 90, and 100% of known resistant strains were prepared and tested for benzimidazole resistance using faecal egg count reduction tests, in vitro egg hatch assays and tubulin binding assays. All tests detected resistance where the proportion of the resistant strain in the composite was 50% or more, whereas none of the tests unequivocally detected resistance below 25%. Egg count reduction tests were no less sensitive than the in vitro tests in detecting low levels of resistance but the egg hatch and tubulin binding assays provided a better quantitative estimate of moderate to high levels of resistance. Faecal egg count reduction therefore, provides a suitable means of detecting resistance in the field but tests, more sensitive to low levels of resistance are required. Results indicate that the use of post-treatment counts alone provides an adequate indication of anthelmintic efficiency.     

Precipitate formation in the strontium-phosphate system

Study of the precipitation process in the aqueous Sr(OH)(2)-H(3)PO(4) system, in order to elucidate the phase transformations and the nature of the final solid phases, shows that over much of the range of compositions studied the initial precipitate is poorly crystalline; the x-ray pattern resembles that of strontium hydroxyapatite but has a strontium: phosphorus molar ratio close to 1.3. Within 1 hour the initial precipitate changes to a stable crystalline phase (or phases), with corresponding change, either up or down, in the strontium: phosphorus ratio. At high ratios of Sr(OH)(2) to H(2)PO(4) the initial precipitate is Sr(3)(PO(4))(2)-4H(2)O, which then converts to a phase having the x-ray diffraction pattern of strontium hydroxyapatite, but having a strontium: phosphorus ratio that depends somewhat on the initial ratio of Sr(OH)(2) to H(3)PO(4) used in the precipitation.