Dynamic expression of alternate splice forms of D-cbl during embryogenesis

The Cbl family of proteins act as E3 ubiquitin-protein ligases and have been associated with the down regulation of a variety of receptor tyrosine kinases. Cbl proteins associate with many different cell signalling molecules suggesting that they may have functions outside of the RING finger-mediated ubiquitin ligase activity. The Drosophila melanogaster cbl gene (D-cbl) encodes two splice forms (Oncogene 19 (2000) 3299). Here we report on the differential expression of these isoforms during Drosophila embryogenesis. Both isoforms are maternally expressed but the long isoform of D-cbl is also transiently expressed in the invaginating mesoderm and later is specifically expressed in neurons of the central nervous system (CNS). Cbl protein is shown to be localised to axons of the longitudinal connectives and commissures in the central nervous system.     

American and korean ginseng tissue cultures: Growth,chemical analysis,and plantlet production

Summary Roots, stems, or leaves of American (Panax quinquefolium) and Korean (Panax ginsing) ginseng were grown as callus or supension tissue cultures. Tissue cultures ofP. ginseng would occasionally form plantlets. The fundamental chemical composition, inorganic analysis, and saponin (panaquilin) content of American and Korean ginseng plants and tissue cultures were determined. The crude saponin content is very similar to, but approximately one-half (1.3%, fresh weight) of that present in ginseng roots. Two-dimensional thin layer chromatographic analysis revealed minor differences in the panaquilins present in American and Korean ginseng tissue cultures. The sapogenin, panaxadiol, was isolated from Korean ginseng callus.     

Neurodevelopmental animal models of schizophrenia: effects on prepulse inhibition

Epidemiological studies have shown increased incidence of schizophrenia in patients subjected to different forms of pre- or perinatal stress. However, as the onset of schizophrenic illness does not usually occur until adolescence or early adulthood, it is not yet fully understood how disruption of early brain development may ultimately lead to malfunction years later. In order to elucidate a possible role for neurodevelopmental factors in the pathogenesis of schizophrenia and to highlight potential new treatments, animal models are needed. Prepulse inhibition (PPI) is a model of sensorimotor gating mechanisms in the brain. It is disrupted in schizophrenia patients and the disruption can be reversed with atypical antipsychotics. It has been widely used in animal studies to explore central mechanisms possibly involved in schizophrenia. There has been a recent surge of behavioural and neurochemical animal studies on neurodevelopmental models, particularly on the effects of postweaning isolation, maternal separation and neonatal lesions of the hippocampus. In these models, long lasting alterations in behaviour and/or molecular changes in specific brain regions are observed, comparable to those seen in schizophrenia. The aim of this article is to critically review the available literature on such neurodevelopmental animal models with special focus on the effects on PPI and brain regions that are putatively involved in regulation of PPI.     

Implementation of an insecticide-treated net subsidy scheme under a public-private partnership for malaria control in Tanzania – challenges in implementation

Background

In the past decade there has been increasing visibility of malaria control efforts at the national and international levels. The factors that have enhanced this scenario are the availability of proven interventions such as artemisinin-based combination therapy, the wide scale use of insecticide-treated nets (ITNs) and a renewed emphasis in indoor residual house-spraying. Concurrently, there has been a window of opportunity of financial commitments from organizations such as the Global Fund for HIV/AIDS, Tuberculosis and Malaria (GFATM), the President's Malaria Initiative and the World Bank Booster programme.

Methods

The case study uses the health policy analysis framework to analyse the implementation of a public-private partnership approach embarked upon by the government of Tanzania in malaria control – 'The Tanzania National Voucher Scheme'- and in this synthesis, emphasis is on the challenges faced by the scheme during the pre-implementation (2001 – 2004) and implementation phases (2004 – 2005). Qualitative research tools used include: document review, interview with key informants, stakeholder's analysis, force-field analysis, time line of events, policy characteristic analysis and focus group discussions. The study is also complemented by a cross-sectional survey, which was conducted at the Rufiji Health Demographic Surveillance Site, where a cohort of women of child-bearing age were followed up regarding access and use of ITNs.

Results

The major challenges observed include: the re-introduction of taxes on mosquito nets and related products, procurement and tendering procedures in the implementation of the GFATM, and organizational arrangements and free delivery of mosquito nets through a Presidential initiative.

Conclusion

The lessons gleaned from this synthesis include: (a) the consistency of the stakeholders with a common vision, was an important strength in overcoming obstacles, (b) senior politicians often steered the policy agenda when the policy in question was a 'crisis event', the stakes and the visibility were high, (c) national stakeholders in policy making have an advantage in strengthening alliances with international organizations, where the latter can become extremely influential in solving bottlenecks as the need arises, and (d) conflict can be turned into an opportunity, for example the Presidential initiative has inadvertently provided Tanzania with important lessons in the organization of 'catch-up' campaigns.     

Glutathione transferase pi class 2 (GSTp2) protects against the cardiac deformities caused by exposure to PAHs but not PCB-126 in zebrafish embryos

Glutathione transferases (GSTs) are phase II enzymes that detoxify a wide range of toxicants and reactive intermediates. One such class of toxicants is the ubiquitous polycyclic aromatic hydrocarbons (PAHs). Certain PAHs are known to cause developmental cardiac toxicity in fish. Herein, we explored the role of GST pi class 2 (GSTp2) in PAH- and PCB-induced cardiac toxicity in zebrafish (Danio rerio) embryos. We measured expression of GSTp2 in embryos exposed to individual and co-exposures of the PAHs benzo[k]fluoranthene (BkF), benzo[a]pyrene (BaP), and fluoranthene (FL) as well as 3,3',4,4',5-pentachlorobiphenyl (PCB-126). GSTp2 mRNA expression was induced by exposure to BkF, BaP, PCB-126, and BaP+FL and BkF+FL co-exposure. A splice junction morpholino was then used to knockdown GSTp2 in developing zebrafish. GSTp2 knockdown exacerbated the toxicity caused by co-exposures to BkF+FL and BaP+FL. However, GSTp2 knockdown did not affect PCB-126 toxicity. These results further suggest that pi class GSTs serve a protective function against the synergistic toxicity caused by PAHs in developing zebrafish.     

Modulation of THP-1 macrophage and cholesterol-loaded foam cell apolipoprotein E levels by glycosphingolipids

Macrophages synthesize and secrete apolipoprotein E (apoE) constitutively. This process is upregulated under conditions of cholesterol loading. The response to cholesterol is antiatherogenic as it is believed to promote cholesterol efflux from the artery wall. The concentration of lactosyl ceramide (LacCer), a glycosphingolipid recently discovered to regulate cellular signaling, proliferation, and expression of adhesion molecules, is also increased in atherosclerotic tissues. Here we have investigated the effect of exogenous LacCer on macrophage apoE levels. We show that increasing macrophage LacCer levels sevenfold led to reductions in cellular and secreted apoE (15 and 30%, respectively, over a 24-h period) as determined by enzyme-linked immunosorbent assay. A similar effect was also induced by glucosyl ceramide (GlcCer) but not by ganglioside species. When macrophages were converted to cholesterol-loaded foam cells by incubation with acetylated LDL, the resulting increase in cellular apoE levels was inhibited by 26% when the cells were subsequently enriched with LacCer. After metabolic labeling of cellular glycosphingolipids with [14C]palmitate, we also discovered that high-density lipoprotein (HDL) stimulates the efflux of glycosphingolipids from foam cells. These data imply that LacCer and GlcCer may be proatherogenic due to the suppression of macrophage apoE production. Furthermore, the efflux of glycosphingolipids from macrophage foam cells to HDL could indicate a potential pathway for their removal from the artery wall and subsequent delivery to the liver.     

Haplotyping cryptic Adélie penguin taxa using low-cost,high-resolution melt curves

Distinguishing morphologically cryptic taxa, by definition, requires genetic data such as DNA sequences. However, DNA sequences may not be obtained easily for taxa from remote sites. Here we provide the details of a high-resolution melt-curve-based method using taxon-specific primers that can distinguish two taxa of Adélie penguins, and that will be usable in Antarctica when combined with some of the newly developed field-deployable thermal cyclers. We suggest that the wider adoption of field-deployable polymerase-chain-reaction-based techniques will enable faster assignation of haplotype to individuals in situ, and so allow the targeting of observations and sample collection to specimens relevant to the research question. Targeting individuals will also reduce the need to repeatedly handle animals and reduce the time and travel required to complete field work.     

The World is a Natural Laboratory,and Social Media is the New Petri Dish

Many high‐priority and high‐interest species are challenging to study due to the difficulty in accessing animals and/or obtaining sufficient sample sizes. The recent explosion in technology, particularly social media and live webcams available on the Internet, provides new opportunities for behavioral scientists to collect data not just on our own species, as well as new resources for teaching and outreach. We discuss here the possibility of exploiting online media as a new source of behavioral data, which we termed ‘video mining’. This article proposes epidemiological and ethological field techniques to gather and screen online media as a data source on diverse taxa. This novel method provides access to a rich source of untapped knowledge, particularly to study the behavior of understudied species or sporadic behaviors, but also for teaching or monitoring animals in challenging settings.     

Biological properties and cell tropism of Chp2, a bacteriophage of the obligate intracellular bacterium Chlamydophila abortus

A number of bacteriophages belonging to the Microviridae have been described infecting chlamydiae. Phylogenetic studies divide the Chlamydiaceae into two distinct genera, Chlamydia and Chlamydophila, containing three and six different species, respectively. In this work we investigated the biological properties and host range of the recently described bacteriophage Chp2 that was originally discovered in Chlamydophila abortus. The obligate intracellular development cycle of chlamydiae has precluded the development of quantitative approaches to assay bacteriophage infectivity. Thus, we prepared hybridomas secreting monoclonal antibodies (monoclonal antibodies 40 and 55) that were specific for Chp2. We demonstrated that Chp2 binds both C. abortus elementary bodies and reticulate bodies in an enzyme-linked immunosorbent assay. Monoclonal antibodies 40 and 55 also detected bacteriophage Chp2 antigens in chlamydia-infected eukaryotic cells. We used these monoclonal antibodies to monitor the ability of Chp2 to infect all nine species of chlamydiae. Chp2 does not infect members of the genus Chlamydia (C. trachomatis, C. suis, or C. muridarum). Chp2 can infect C. abortus, C. felis, and C. pecorum but is unable to infect other members of this genus, including C. caviae and C. pneumoniae, despite the fact that these chlamydial species support the replication of very closely related bacteriophages.