Adoptive transfer of CD8+ T cells from immune animals does not transfer immunity to blood stage Plasmodium yoelii malaria

The malaria parasite, Plasmodium yoelii 17X, causes a self-limited, nonlethal infection characterized, in the blood stage, by preferential invasion of reticulocytes. Previous studies have suggested that immunity to the blood stage infection may be related to enhanced levels of class I MHC Ag on the parasitized reticulocyte surface and can be adoptively transferred to immunodeficient mice by immune CD8+ T cells in the absence of CD4+ T cells. To further examine the mechanisms of CD8+ T cell involvement in immunity to blood stage P. yoelii infection, we performed in vivo CD8 depletion and adoptive transfer experiments. Depletion of CD8+ T cells during primary blood stage infection in BALB/c mice did not diminish the ability of the mice to resolve their infections. Spleen cells from immune BALB/c and C57BL/10 mice were transferred to BALB/c-nu/nu and C57BL/10-nu/nu mice, respectively. The recipient mice were CD4 depleted in vivo to kill any transferred CD4+ T cells. The mice failed to control the infection. Populations of CD4-, CD8+ T cells were transferred from immune CBA/CaJ donors to in vivo CD4-depleted CBA/CaJ recipients. The mice were unable to control the infection. Although immune unfractionated spleen cells transferred rapid protection in all three mouse strains and immune CD4+ T cells transferred immunity in the two mouse strains studied, CD8+ T cells by themselves were neither protective nor did they enhance immunity.     

Curtailment and acoustic deterrents reduce bat mortality at wind farms

The impacts of wind energy on bat populations is a growing concern because wind turbine blades can strike and kill bats, and wind turbine development is increasing. We tested the effectiveness of 2 management actions at 2 wind-energy facilities for reducing bat fatalities: curtailing turbine operation when wind speeds were <5.0 m/second and combining curtailment with an acoustic bat deterrent developed by NRG Systems. We measured the effectiveness of the management actions using differences in counts of bat carcasses quantified by daily and twice-per-week standardized carcass searches of cleared plots below turbines, and field trials that estimated searcher efficiency and carcass persistence. We studied turbines located at 2 adjacent wind-energy facilities in northeast Illinois, USA, during fall migration (1 Aug–15 Oct) in 2018. We estimated the effectiveness of each management action using a generalized linear mixed-effects model with several covariates. Curtailment alone reduced overall bat mortality by 42.5% but did not reduce silver-haired bat (Lasionycteris noctivagans) mortality. Overall bat fatality rates were 66.9% lower at curtailed turbines with acoustic deterrents compared to turbines that operated at manufacturer cut-in speed. Curtailment and the deterrent reduced bat mortality to varying degrees between species, ranging from 58.1% for eastern red bats (Lasiurus borealis) to 94.4 for big brown bats (Eptesicus fuscus). Hoary (Lasiurus cinereus) and silver-haired bat mortality was reduced by 71.4% and 71.6%, respectively. Our study lacked a deterrent-only treatment group because of the expense of acoustic deterrents. We estimated the additional reduction in mortality with concurrent deployment of the acoustic deterrent and curtailment under the assumption that curtailment and the acoustic deterrent would have reduced mortality by the same percentage at adjacent wind-energy facilities. Acoustic deterrents resulted in 31.6%, 17.4%, and 66.7% additional reductions of bat mortality compared to curtailment alone for eastern red bat, hoary bat, and silver-haired bat, respectively. The effectiveness of acoustic deterrents for reducing bat mortality at turbines with rotor-swept area diameters >110 m is unknown because high frequency sound attenuates quickly, which reduces coverage of rotor-swept areas. Management actions should consider species differences in the ability of curtailment and deterrents to reduce bat mortality and increase energy production.     

DataBiNS: a BioMoby-based data-mining workflow for biological pathways and non-synonymous SNPs

DataBiNS is a custom-designed BioMoby Web Service workflow that integrates non-synonymous coding single nucleotide polymorphisms (nsSNPs) data with structure/function and pathway data for the relevant protein. A KEGG Pathway Identifier representing a specific human biological pathway initializes the DataBiNS workflow. The workflow retrieves a list of publications, gene ontology annotations and nsSNP information for each gene involved in the biological pathway. Manual inspection of output data from several trial runs confirms that all expected information is appropriately retrieved by the workflow services. The use of an automated BioMoby workflow, rather than manual 'surfing', to retrieve the necessary data, significantly reduces the effort required for functional interpretation of SNP data, and thus encourages more speculative investigation. Moreover, the modular nature of the individual BioMoby Services enables fine-grained reusing of each service in other workflows, thus reducing the effort required to achieve similar investigations in the future. AVAILABILITY: The workflow is freely available as a Taverna SCUFL XML document at the iCAPTURE Centre web site, http://www.mrl.ubc.ca/who/who_bios_scott_tebbutt.shtml.     

Relative Efficacy of Selected Volatile and Nonvolatile Nematicides for Control of Meloidogyne incognita on Tobacco

Root-knot nematode control and tobacco yields in plots infested with Meloidogyne incognita and treated with the nonvolatile nematicides, aldicarb, Mocap ®, or Nemacur ® were greater than those on similar plots treated with volatile nematicides such as DD, DD + MENCS, SD14647 or tetrachlorothiophene. Root-knot control and tobacco yields in plots treated with carbofuran or Dasanit ® were eqtual to that obtained with DD + MENCS, but less than that obtained with the other volatile soil nematicides. The most efficient dosage was 3.4 kg/hectare active ingredient for aldicarb and Mocap ® and 10.0 kg/hectare for Dasanit ®. Carbofuran and Nemacur ® were equally as effective at 4.2 kg/hectare as they were at higher dosages. The most efficient dosage of DD and SD14647 was 84 liters/hectare. Aldicarb and Dasanit ® resulted in better nematode control and tobacco yields when incorporated into the top 15-20 cm of soil than when incorporated into the top 5-10 cm of soil. Nemacur ® and Mocap ® performed better when incorporated into the top 5-10 cm of soil, and carbofuran performed better when applied in the seed furrow (placed 15-20 cm deep in a 5-cm band and bedded).     

A non-calcemic Vitamin D analog modulates both nuclear and putative membranal estrogen receptors in cultured human vascular smooth muscle cells

In cultured human vascular smooth muscle cells (VSMC), estradiol-17beta (E2) induced a biphasic effect on DNA synthesis, i.e., stimulation at low concentrations and inhibition at high concentrations. Additionally, E2 increased the specific activity of creatine kinase (CK) in these cells. Observations that novel protein-bound membrane impermeant estrogenic complexes could elicit inhibition of DNA synthesis, suggested interaction via membranal binding sites. Nevertheless other effects, such as increasing CK activity were only seen with native E2 but not with E2-BSA, thus indicating that the classical nuclear receptor pathway was involved. In the present report, we confirm that human VSMC express both ERalpha and ERbeta. Further, pretreatment of cultured VSMC with the Vitamin D non-calcemic analog JK 1624 F2-2 (JKF) increased ERalpha mRNA (100-200%) but decreased ERbeta mRNA (30-40%) expression as measured by real time PCR. ERalpha protein expression assessed by Western blot analysis increased (25-50%) in parallel, whereas ERbeta protein expression declines (25-55%). Using ovalbumin bound to E2 (Ov-E2) linked to Eu (Eu-Ov-E2), to assess specific membrane binding sites, we observed that membranal binding was down regulated by JKF by 70-80%. In contrast, total cell binding of 3[H] E2, that nearly entirely represents intracellular E2 binding, was increased by 60-100% by the same Vitamin D analog. The results provide evidence that the effects of JKF on ERalpha/ERbeta as well as on membranal versus nuclear binding of estrogen are divergent and show differential modulation.     

BOTRYOPTERIS PINNULES WITH ABAXIAL SPORANGIA

Small sporangia borne abaxially on pinnules attached to Botryopteris foliar members are described from coal ball petrifactions of Early Pennsylvanian age. This is the first report of laminar sporangia in this genus. Sporangia are stalked and borne singly near lateral veins on Sphenopteris-like pinnules. Individual sporangia are of the leptosporangiate type, with a lateral annulus and a dehiscence zone of thin-walled cells immediately adjacent to the annulus. Spores are small, trilete, triangular in outline, typically have blunt spines covering the exine, and correspond to the dispersed spore genera Acanthotriletes, Leiotriletes, or Lophotriletes. These sporangia and their spores are unlike previously described globose Botryopteris fructifications from the Middle and Upper Pennsylvanian, but are similar to sporangia produced by modern members of the Osmundaceae.     

Glycosylation of PrPC Determines Timing of Neuroinvasion and Targeting in the Brain following Transmissible Spongiform Encephalopathy Infection by a Peripheral Route

Transmissible spongiform encephalopathy (TSE) infectivity naturally spreads from site of entry in the periphery to the central nervous system where pathological lesions are formed. Several routes and cells within the host have been identified as important for facilitating the infectious process. Expression of the glycoprotein cellular PrP (PrP^C) is considered a key factor for replication of infectivity in the central nervous system (CNS) and its transport to the brain, and it has been suggested that the infectious agent propagates from cell to cell via a domino-like effect. However, precisely how this is achieved and what involvement the different glycoforms of PrP have in these processes remain to be determined. To address this issue, we have used our unique models of gene-targeted transgenic mice expressing different glycosylated forms of PrP. Two TSE strains were inoculated intraperitoneally into these mice to assess the contribution of diglycosylated, monoglycosylated, and unglycosylated PrP in spreading of infectivity to the brain. This study demonstrates that glycosylation of host PrP has a profound effect in determining the outcome of disease. Lack of diglycosylated PrP slowed or prevented disease onset after peripheral challenge, suggesting an important role for fully glycosylated PrP in either the replication of the infectious agent in the periphery or its transport to the CNS. Moreover, mice expressing unglycosylated PrP did not develop clinical disease, and mice expressing monoglycosylated PrP showed strikingly different neuropathologic features compared to those expressing diglycosylated PrP. This demonstrates that targeting in the brain following peripheral inoculation is profoundly influenced by the glycosylation status of host PrP.Transmissible spongiform encephalopathies (TSE) or prion diseases are a group of fatal neurodegenerative diseases which include Creutzfeldt-Jakob disease (CJD) in humans, scrapie in sheep and goats, bovine spongiform encephalopathies (BSE) in cattle, and chronic wasting disease (CWD) in deer and elk (30). These diseases can be sporadic, familial, or acquired by infection, and the common hallmark is a distinct pathology in the central nervous system (CNS) characterized by neuronal loss, spongiform degeneration, and gliosis (38, 46).Expression of the host-encoded cellular PrP (PrP^C) is fundamental for the onset of disease since PrP-deficient mice are refractory to TSE infection (11, 31). PrP^C is a glycoprotein with two consensus sites for attachment of N-linked glycans (at codons 180 and 196 in the mouse) which are variably occupied, producing di-, mono-, and unglycosylated PrP (43). The diversity in glycosylation, combined with the complexity of added sugars, results in a large number of glycosylated forms of PrP (41). A central event associated with TSE infection is the conformational conversion of PrP^C into an abnormal protease-resistant form, PrP^Sc (39). PrP^Sc is deposited in brain and, in some but not all cases, in peripheral organs of individuals affected by TSE (21).Although the pathology associated with TSE is found in the brain, the periphery is the most natural route of acquiring infection. Evidence suggests that oral transmission via contaminated food is linked with transmission of BSE to humans, resulting in variant CJD (vCJD) (10, 47), and blood transfusion has been identified as a probable route of human-to-human transmission of vCJD (23, 27, 36). Moreover, parenteral administration of contaminated human tissue-derived therapeutics has been shown to facilitate iatrogenic spread of these diseases (8, 46). It is therefore important to understand the mechanisms that allow the infectious agent to propagate in the periphery and be transported to the CNS prior to the onset of neurodegeneration in the brain.Many studies have been conducted to understand routes of transmission (for a review see references 1 and 29). Lymphoid tissues such as the spleen have been shown to play a fundamental role in agent replication and propagation in the very early stages of disease. Indeed, studies of splenectomized and asplenic mice have shown the lymphoreticular system (LRS) to be an important site for TSE agent replication (14, 26). The periphery also appears to have a role in processing the infectious agent following intracerebral (i.c.) inoculation as PrP^Sc accumulates in the spleen shortly after inoculation and before accumulation of the abnormal protein in the brain (15, 17). Within the LRS, follicular dendritic cells (FDC) have been shown to be important for the uptake of infectivity and subsequent spreading toward the CNS (7, 28, 33, 35). Several studies have also suggested the peripheral nervous systems (PNS) as a potential route of infectivity to the brain, implicating the vagus and sciatic nerves in this process (5, 20, 25, 34).Expression of PrP^C in the peripheral tissues appears to be an important prerequisite for the transport of infectivity to the CNS following peripheral routes of inoculation. Indeed, it has been proposed that a continuous chain of cells expressing PrP^C is fundamental for TSE neuroinvasion (6, 40), with overexpression of endogenous PrP in the PNS greatly facilitating the spread of infectivity (19). Thus, host PrP appears to have a fundamental role in the uptake, transport, and replication of the infectious agent (6). Moreover, it has been suggested that the different PrP^C glycoforms may influence the timing of neuroinvasion by directly influencing the interaction with the infectious agent (19). However, the mechanism by which the different glycoforms are involved in these processes remains to be determined.In order to investigate the role of PrP^C glycosylation in TSE disease after peripheral infection with different TSE strains, we have used our inbred gene-targeted transgenic mice expressing different glycosylated forms of PrP. These mice expressed PrP with no sugars at the first (designated G1/G1 in homozygous mice) or the second glycosylation site (G2/G2) or both (G3/G3) under the control of the endogenous PrP promoter (13). We have previously shown that following intracerebral inoculation, all glycotypes are susceptible to infection with at least one TSE strain and that the type of PrP glycosylation in the host influenced the incubation period but not the distribution of pathological lesions in the brain (45). Here, we examine the influence of host PrP glycosylation on the peripheral acquisition of infection and demonstrate that, unlike the intracerebral route, mice without PrP glycosylation were resistant to disease and that the different glycoforms had a profound influence on not only the timing of disease but also the type and distribution of the PrP^Sc deposits in the brain.     

Selectively bred oysters can alter their biomineralization pathways,promoting resilience to environmental acidification

Commercial shellfish aquaculture is vulnerable to the impacts of ocean acidification driven by increasing carbon dioxide (CO₂) absorption by the ocean as well as to coastal acidification driven by land run off and rising sea level. These drivers of environmental acidification have deleterious effects on biomineralization. We investigated shell biomineralization of selectively bred and wild‐type families of the Sydney rock oyster Saccostrea glomerata in a study of oysters being farmed in estuaries at aquaculture leases differing in environmental acidification. The contrasting estuarine pH regimes enabled us to determine the mechanisms of shell growth and the vulnerability of this species to contemporary environmental acidification. Determination of the source of carbon, the mechanism of carbon uptake and use of carbon in biomineral formation are key to understanding the vulnerability of shellfish aquaculture to contemporary and future environmental acidification. We, therefore, characterized the crystallography and carbon uptake in the shells of S. glomerata, resident in habitats subjected to coastal acidification, using high‐resolution electron backscatter diffraction and carbon isotope analyses (as δ¹³C). We show that oyster families selectively bred for fast growth and families selected for disease resistance can alter their mechanisms of calcite crystal biomineralization, promoting resilience to acidification. The responses of S. glomerata to acidification in their estuarine habitat provide key insights into mechanisms of mollusc shell growth under future climate change conditions. Importantly, we show that selective breeding in oysters is likely to be an important global mitigation strategy for sustainable shellfish aquaculture to withstand future climate‐driven change to habitat acidification.     

Introgression potential between safflower (Carthamus tinctorius) and wild relatives of the genus Carthamus

Background  

Safflower, Carthamus tinctorius, is a thistle that is grown commercially for the production of oil and birdseed and recently, as a host for the production of transgenic pharmaceutical proteins. C. tinctorius can cross with a number of its wild relatives, creating the possibility of gene flow from safflower to weedy species. In this study we looked at the introgression potential between different members of the genus Carthamus, measured the fitness of the parents versus the F1 hybrids, followed the segregation of a specific transgene in the progeny and tried to identify traits important for adaptation to different environments.     

Peptide nucleic acid (PNA) antisense effects in Escherichia coli

Antisense peptide nucleic acid (PNA) can be used to control cell growth, gene expression and growth phenotypes in the bacteria Escherichia coli. PNAs targeted to the RNA components of the ribosome can inhibit translation and cell growth, and PNAs targeted to mRNA can limit gene expression with gene and sequence specificity. In an E. coli cell extract, efficient inhibition is observed when using PNA concentrations in the nanomolar range, whereas micromolar concentrations are required for inhibition in growing cells. A mutant strain of E. coli that is more permeable to antibiotics also is more susceptible to antisense PNAs than the wild type. This chapter details methods for testing the antisense activities of PNA in E. coli. As an example of the specific antisense inhibition possible, we show the effects of an anti-beta-galactosidase PNA in comparison to control PNAs. With improvements in cell uptake, antisense PNAs may find applications as antimicrobial agents and as tools for microbial functional genomics.