A Paradoxical Kind of Sleep in Drosophila melanogaster

1. Download : Download high-res image (268KB)
2. Download : Download full-size image

     

Human serologic response to subcellular antigens of Trichomonas vaginalis

Trichomonas vaginalis organisms were processed by differential centrifugation to yield defined subcellular fractions. The various fractions were processed by methods to enhance solubility of membranes and other components. The soluble materials were analyzed for immunogenicity by a quantitative kinetic enzyme-linked immunosorbent assay (k-ELISA) and the enzyme-linked immunoelectrotransfer blot (EITB) technique using human patient serum. The principal antibodies in the human serum were directed toward cytosol components, not against membrane components, although all fractions contained multiple antigenic moieties.     

Translocations of digging mammals and their potential for ecosystem restoration: a review of goals and monitoring programmes

1. Globally, translocations are commonly used to improve the conservation status of threatened species. There is increasing recognition that translocations of ecosystem engineers also have the potential to restore ecological processes. Digging mammals are often considered to be ecosystem engineers, as their diggings provide shelter for other species and can significantly alter soil properties, with subsequent changes to vegetation.
2. Using Australian species as a case study, we reviewed published and grey literature on digging mammal translocations to determine how often these translocations are conducted to restore ecosystem processes. We documented ecosystem-level monitoring and research efforts, and assessed whether restoration was perceived to be occurring post-release.
3. At least 208 translocations of 24 digging mammal species have been conducted in Australia, with a further 38 planned for the near future. Prior to 2019, only 3% of translocations included a goal relating to the restoration of ecosystem processes associated with digging activities. Nearly a quarter of pre-2019 translocations have been the subject of some form of ecosystem-level monitoring or research, but long-term ecosystem-level monitoring was very rare. In contrast, 74% of the translocations planned for post-2018 include a goal relating to the restoration of ecological processes and most also include plans to conduct ecosystem-level monitoring.
4. Ecosystem restoration was perceived to be occurring for 26% of the pre-2019 translocations. None of the documents we reviewed indicated that ecological degradation had occurred post-translocation, even when declines in other taxa were recorded.
5. The restoration of ecosystem processes is increasingly being identified as a goal for translocation programmes. Where this is the case, we suggest that translocation practitioners include success criteria for the restoration of ecosystem processes, and commit to long-term monitoring designed to detect ecosystem-level effects of translocations.

     

Differential mRNA display analysis of two related but functionally distinct rat insulinoma (RIN) cell lines: identification of CD24 and its expression in the developing pancreas

To identify genes that might play a role in growth and differentiation of pancreatic beta-cells, we have applied the technique of differential mRNA display to the lineage-related, but functionally distinct rat insulinoma (RIN) cell lines RIN-5AH and RIN-A12. Direct comparison of PCR-generated RIN-5AH and RIN-A12 cDNAs on DNA sequencing gels revealed 31 differentially expressed bands. By Northern blot hybridization, authentic differential expression was confirmed for three cDNAs derived from RIN-5AH cells and four cDNAs from RIN-A12 cells. Nucleotide sequences were determined for these cDNAs and database searches identified one known gene that encoded heat stable antigen CD24. Of the remaining six genes, three matched with established sequence tags from fetal tissue, and three were potentially novel. By RT-PCR analysis, five of the seven genes were expressed in normal fetal and/or adult pancreas. In a detailed survey of CD24 protein expression in the pancreas using the CD24-specific monoclonal antibody J11d, CD24 was predominantly expressed in ductal epithelial cells (E13.5-15.5), developing endocrine (alpha, beta and delta) and exocrine cells (E15.5-20.5) and mature exocrine and peripheral islet delta-cells post E20.5. The retention of CD24 expression in a large proportion of delta-cells but only in a minority of alpha- and beta-cells leads us to hypothesize that CD24 may mark a pool of precursor endocrine cells within adult islets.     

Optimisation of Microbial 3-methylcatechol Production as Affected by Culture Conditions

Pseudomonas putida MC2 can be used to produce catechols. The accumulation, specific and volumetric production rates of 3-methylcatechol from toluene have been studied. Production rates were shown to depend on growth medium, pH and toluene concentration. Minimal glucose medium and rich LB medium were the best growth media for 3-methylcatechol production. A lower pH often resulted in slower growth and a higher specific production rate, but a lower volumetric production rate. Specific production rates also increased at higher initial toluene concentrations. The best process conditions in terms of substrate conversion and specific production rate were found in minimal glucose medium at an initial aqueous toluene concentration of 1.0 λmM and an initial pH of 6. At pH 7 and 2.0 λmM toluene, more product was accumulated at a lower specific rate, but at a higher volumetric production rate.     

Influence of physical processes on the design, functioning and evolution of restored tidal wetlands in California (USA)

The performance of two intertidal wetland mitigation projects constructed by the California Department of Transportation (Caltrans) in the Sweetwater Marsh National Wildlife Refuge (SMNWR) in San Diego Bay was evaluated over 5 years. Most of the Sweetwater wetland complex has been altered this century, including diking (with subsequent subsidence), filling, modification of the tidal regime, freshwater inflow and sediment fluxes. The mitigation project goals included a range of functional criteria intended to support two endangered bird species (light-footed clapper rail and California least tern) and one endangered plant (salt marsh bird's-beak). While the mitigation projects have achieved some of the performance criteria established in the regulatory permits (particularly, those related to fish), vegetation criteria for one of the bird species have not been met. The initial grading (in relation to local tidal datums) should support the target plant species, but growth has been less than required. Shortcomings of the habitat include elevated soil and groundwater salinity, low nutrient levels (especially nitrogen, which is readily leached from the coarse substrate), and eroding topography (where a single oversized and overly sinous channel and the lower-than-natural marshpalin result in high velocity surface water flow and erosion). The failure to achieve a large plain at low-marsh elevations highlights the importance of a more complete understanding of the relationship between the site physical processes (topography, hydrology, climate, geomorphology), substrate conditions, and biotic responses.Corresponding editor: R.E. Turner