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Successful treatment of dilute ethylene glycol based-aircraft de-icing fluid (ADF) was achieved using a four compartment, anaerobic baffled reactor (ABR). Three ADF concentrations (0.04, 0.07, and 0.13%v/v) were continuously fed at different hydrological retention times (HRTs; 24, 12, 6 and 3h) with concomitant organic loading rates (OLRs) varying between 0.3 and 6 kg chemical oxygen demand (COD)/m(3)/d. ABR achieved over 75% soluble COD removal and an average methane production potential of 0.30+/-0.05LCH(4)/gCOD(removed) at 33 degrees C for the experimental conditions evaluated. The different experimental conditions tested and a four-month summer shut-down simulation had no significant effect on reactor performance or on the settling characteristics of the granular biomass, which remained almost constant during the study. Biomass specific acetoclastic activity however, changed through the study; increasing two fold for the last three compartments and decreasing almost the same magnitude for the first compartment compared to inoculum, suggesting that a new distribution of microbial consortia was established in each compartment of the reactor by the end of the study.

Activated sludge model No. 2d (ASM2d) was calibrated then used to determine optimal recycle rates and basin retention times, with respect to final N, soluble P (sP) or N plus sP concentrations for Modified Bardenpho (MB), Modified University of Cape Town (MUCT), and anaerobic–anoxic–oxic (A2O) biological nutrient removal processes. Simulations were conducted at two temperatures and three primary effluent (PE) concentrations (COD, TSS, TKN, sP). All BNR processes were shown to be capable of achieving an effluent sP concentration below 1 mg/L at all conditions when effluent N concentration was neglected. None of the processes were capable of producing an effluent with N concentrations below 5 mg/L at high PE concentration. The MB and MUCT processes were both successful in achieving a combined sP and N removal below 1 mg/L and 5 mg/L for low PE concentrations at 10 and 20 ºC. Only the MB process, at 20 ºC with medium PE concentrations, was found to achieve an effluent below 1 mg/L and 5 mg/L, respectively for sP and N. Recycle from the anoxic basin of the MUCT process had an insignificant effect on N and sP removals. All input variables to the MB and A2O process proved to be somewhat significant and it is recommended that they be kept within future experimental designs. Dynamic tests with real Ottawa plant influent flow data indicated that the MB process was more robust with respect to TN, sP, and CBOD5 removal than the MUCT process.Key words: activated sludge, biological nutrient removal, simulation, model, ASM2d.

Theiler's murine encephalomyelitis virus induces a demyelinating disease (TMEV-IDD) of the central nervous system (CNS) in susceptible mouse strains with accompanying histopathology characterized by mononuclear cell infiltrates. In susceptible strains of mice such as SJL, virus establishes a persistent infection in macrophages, induces a CNS infiltration by macrophages, T cells, and B cells, which results in chronic-progressive paralysis. In the present report the authors have investigated the functional role of CCL2 (monocyte chemotactic protein-1) in the induction and progression of demyelinating disease. Treatment of infected mice at day 0, 14, or 28 with anti-CCL2 resulted in a significant decrease in the clinical disease progression. Further analysis of anti-CCL2–treated mice revealed decreased CNS inflammation and mononuclear cell infiltration with an accompanying change in inflammatory cytokine responses. There was an overall decrease in the absolute numbers of CNS-infiltrating CD4+ T cells, macrophages, and B cells. Finally, anti-CCL2 treatment resulted in decreased viral load in the CNS. These data directly demonstrate a role for CCL2 in the pathogenesis of TMEV-IDD.

CC chemokine ligand 2 (CCL2)/monocyte chemotactic protein-1, a member of the CC chemokine family, is a chemoattractant for monocytes and T cells through interaction with its receptor CCR2. In the present study, we examined a T helper cell type 1 (Th1)-dependent disease, proteolipid protein-induced experimental autoimmune encephalomyelitis, in a transgenic mouse line that constitutively expressed low levels of CCL2 in the central nervous system (CNS) under control of the astrocyte-specific glial fibrillary acidic protein promoter. CCL2 transgenic mice developed significantly milder clinical disease than littermate controls. As determined by flow cytometry, mononuclear cell infiltrates in the CNS tissues of CCL2 transgenic and littermate-control mice contained equal numbers of CD4+ and CD8+ T cells, and the CCL2 transgenic mice showed an enhanced number of CNS-infiltrating monocytes. CNS antigen-specific T cells from CCL2 transgenic mice produced markedly less interferon-γ. Overexpression of CCL2 in the CNS resulted in decreased interleukin-12 receptor expression by antigen-specific T cells. Collectively, these results indicate that sustained, tissue-specific expression of CCL2 in vivo down-regulates the Th1 autoimmune response, culminating in milder clinical disease.

Pathogenic protozoa such as Trypanosome and Leishmania species cause tremendous suffering worldwide. Because of their dependence on glycolysis for energy, the glycolytic enzymes of these organisms, including glycerol-3-phosphate dehydrogenase (GPDH), are considered attractive drug targets. Using the adenine part of NAD as a lead compound, several 2,6-disubstituted purines were synthesized as inhibitors of Leishmania mexicana GPDH (LmGPDH). The electron densities for the inhibitor 2-bromo-6-chloro-purine bound to LmGPDH using a “conventional” wavelength around 1 Å displayed a quasisymmetric shape. The anomalous signals from data collected at 1.77 Å clearly indicated the positions of the halogen atoms and revealed the multiple binding modes of this inhibitor. Intriguing differences in the observed binding modes of the inhibitor between very similarly prepared crystals illustrate the possibility of crystal-to-crystal variations in protein-ligand complex structures.

Experimental autoimmune encephalomyelitis (EAE) is a CD4+ Th1-mediated demyelinating disease of the CNS that serves as a model for multiple sclerosis. A critical event in the pathogenesis of EAE is the entry of both Ag-specific and Ag-nonspecific T lymphocytes into the CNS. In the present report, we investigated the role of the CXC chemokine CXCL10 (IFN-γ-inducible protein-10) in the pathogenesis of EAE. Production of CXCL10 in the CNS correlated with the development of clinical disease. Administration of anti-CXCL10 decreased clinical and histological disease incidence, severity, as well as infiltration of mononuclear cells into the CNS. Anti-CXCL10 specifically decreased the accumulation of encephalitogenic PLP139–151 Ag-specific CD4+ T cells in the CNS compared with control-treated animals. Anti-CXCL10 administration did not affect the activation of encephalitogenic T cells as measured by Ag-specific proliferation and the ability to adoptively transfer EAE. These results demonstrate an important role for the CXC chemokine CXCL10 in the recruitment and accumulation of inflammatory mononuclear cells during the pathogenesis of EAE.

N6-Naphthalenemethyl-2'-methoxybenzamido-beta-NAD+, a derivative of a low micromolar first-generation inhibitor of trypanosomal glyceraldehyde phosphate dehydrogenase (GAPDH), was synthesized, taking advantage of methodology for the selective phosphitylation of nucleosides. The compound was found to be a poor alternate cosubstrate for GAPDH, but an extremely potent inhibitor. Although intended for use in crystallization trials, the analogue presents possibilities for further drug design.

Experimental autoimmune encephalomyelitis (EAE) is a CD4+ Th1-mediated demyelinating disease of the central nervous system (CNS), which serves as a model for multiple schlerosis (MS). A hallmark in the pathogenesis of this disease is the emigration of T cells and monocytes from the blood to the CNS. Chemokines are small-molecular-weight chemotactic peptides, which are ligands for seven transmembrane-spanning, G protein-coupled receptors and which deliver signals leading to a variety of T cell functions including costimulation, cytokine expression, differentiation, and integrin activation. Several considerations suggest a role for chemokines in the influx of inflammatory cells to the CNS and the resulting disease process, including a tight temporal expression pattern with a relation to disease activity and prevention of disease development by in vivo neutralization. This article reviews the evidence that temporal and spatial expressions of chemokines are critical factors that regulate EAE, which makes this an appropriate animal model to study the pathogenesis of MS disease activity.

Chemokines are low molecular weight chemotactic peptides that bind seven transmembrane-spanning, G protein-coupled receptors and deliver signals leading to T cell costimulation, hematopoeisis, cytokine expression, T cell differentiation, and integrin activation. Experimental autoimmune encephalomyelitis (EAE) is a CD4+ Th1-mediated demyelinating disease of the central nervous system (CNS) that serves as a model for multiple sclerosis (MS). A hallmark in the pathogenesis of this CNS demyelinating disease is the emigration of T cells and monocytes from the blood to the CNS. There are several considerations that suggest a role for chemokines in the influx of inflammatory cells and the resulting disease process including a tight temporal expression pattern with relationship to disease activity and prevention of disease development by in vivo neutralization. We review the evidence that temporal and spatial expressions of chemokines are crucial factors, complementing adhesion molecule upregulation, that regulate EAE and potentially MS disease activity as well as the functions of chemokines in Th1 and Th2 biology.

Experimental autoimmune encephalomyelitis (EAE) is a T cell–mediated autoimmune demyelinating disease of the central nervous system that serves as an animal model for multiple sclerosis. Antigen-specific tolerance regimens, including oral tolerance, have been used prophylactically to prevent development of acute EAE as well as a number of other autoimmune diseases. Two mechanisms have been proposed to explain the immunologic basis for disease inhibition: bystander immune suppression and clonal anergy/deletion. This report demonstrates a novel mechanism for monocyte chemotactic protein (MCP)-1 as a regulatory factor of oral tolerance. Oral administration of proteolipid protein peptide (PLP139–151) increased MCP-1 expression in the intestinal mucosa, Peyer's patch, and mesenteric lymph nodes. Increase in MCP-1 expression resulted in downregulation of mucosal interleukin (IL)-12 expression with concomitant increase in mucosal IL-4 expression. Functionally, MCP-1 upregulation was shown to regulate oral tolerance induction by the ability of antibodies to MCP-1 to inhibit tolerance induction. The anti–MCP-1 abrogation of oral tolerance induction also resulted in restoration of mucosal IL-12 expression as well as peripheral antigen-specific T helper cell 1 responses. These results demonstrate a novel and important role for MCP-1 in the regulation or oral tolerance for the prevention and treatment of autoimmune disease.

Chemokines are a family of small-molecular-weight cytokines that induce chemotaxis and chemokinesis of leukocytes. These molecules are ligands for seven-transmembrane, G-protein-linked receptors and are known to activate integrins on the surface of leukocytes and other cells as well as induce a number of signaling events. They play a significant role in the migration of leukocytes from blood into tissue during inflammatory processes. We tested the role of chemokines in experimental autoimmune encephalomyelitis (EAE) and found that macrophage inflammatory protein-1α (MlP-1α) correlated with acute disease development, whereas monocyte chemotactic protein-1 (MCP-1) did not. In contrast, MCP-1 production in the central nervous system correlated with relapsing EAE development. Moreover, anti-MIP-1α, but not anti-MCP-1, inhibited development of acute but not relapsing EAE, whereas anti-MCP-1 significantly reduced the severity of relapsing EAE. To test the effects of chemokines on the differentiation of naive T cells, TCR transgenic splenic T cells (Tg+ T cells) from DO11.10 OVA TCR transgenic mice were used as a source of Th0 cells and were stimulated with specific anti-clonotypic monoclonal antibodies in the presence of MIP-1α, MCP-1, or controls. MIP-1α drove Th0 cells to differentiate to Th1, whereas MCP-1 drove Th0 cells to differentiate to Th2. Similarly, MCP-1, but not MlP-1α significantly inhibited the adoptive transfer of EAE when included in in vitro activation cultures, further suggesting a regulatory anti-inflammatory property. These results suggest a differential role for CC chemokines in the development and activation of T cells during autoimmune inflammatory diseases.

Peripheral antigen-specific tolerance can be induced by feeding protein antigens. The mechanism has been described as either clonal anergy/deletion or induction of antigen-specific regulatory cells that produce transforming growth factor-beta (TGF-beta). These two mechanisms have been linked to the magnitude and frequency of the dose of antigen fed; a single high dose induces anergy/deletion, whereas multiple low doses of antigen induce TGF-beta-secreting regulatory cells. In the present study, we investigated the mechanisms of feeding soluble peptides of proteolipid protein (PLP) for prevention of experimental autoimmune encephalomyelitis (EAE) induced by either intact PLP or the immunodominant PLP139-151 peptide. Feeding PLP139-151 prevented acute and relapsing EAE induced by either PLP139-151 or intact PLP. PLP139-151 feeding induced anergy in the T helper 1 (Th1) population as measured by an inhibition of both proliferation and interferon-gamma (IFN-gamma) production. Interleukin-4 (IL-4) production was increased, but increased TGF-beta production was not observed. Importantly, PLP139-151 feeding induced anergy in peripheral and central nervous system (CNS)-in-filtrating T cells. Feeding of the subdominant PLP epitope (PLP178-191) failed to inhibit EAE induced by PLP139-151; therefore, oral tolerance was not due to induction of bystander suppression. These results demonstrate that both acute and relapsing paralysis in EAE can be prevented by feeding the immunodominant peptide of PLP.

Chemokine-induced lymphocyte migration has long been hypothesized to regulate the appearance and continued presence of lymphocytes and monocytes in tissue-specific autoimmune diseases, including central nervous system autoimmune diseases such as multiple sclerosis. For instance, a large body of evidence points to the temporal association of chemokine expression with the appearance of T lymphocytes and monocytes/macrophages. Furthermore, experiments using mice with targeted mutations for chemokines have shown the importance of those molecules in the development of central nervous system autoimmune disease. We have hypothesized that temporal and spatial expression of chemokines is a key factor in the pathogenesis of experimental autoimmune encephalomyelitis and multiple sclerosis. To test our hypothesis we have employed the strategy of eliminating chemokine function by the passive transfer of chemokine-specific polyclonal antibodies. This approach has allowed us not only to test the function of chemokines in experimental autoimmune encephalomyelitis development, but also to ask questions about the roles of chemokines during disease progression. Moreover, this approach has allowed us to assess the efficacy of targeting chemokines and their receptors for treatment of ongoing disease. In the present report we summarize our experience using anti-chemokine administration for the prevention and treatment of experimental autoimmune encephalomyelitis as well as provide specific examples of how this approach is efficacious for disease treatment.

Experimental autoimmune encephalomyelitis (EAE) is a T cell mediated demyelinating disease of the central nervous system (CNS) that serves as a model for multiple sclerosis (MS). Insights into the pathogenesis of this model may help scientists understand the human disease and aid in rational drug discovery. In this review we summarize the role of chemokines and chemokine receptors in disease pathogenesis and suggest a pathway of events that leads to demyelination and subsequent clinical disease manifestation.

Pathogenic strains of the soilborne fungus Periconia circinata produce peritoxins with host-selective toxicity against susceptible genotypes of sorghum. The peritoxins are low-molecular-weight, hybrid molecules consisting of a peptide and a chlorinated polyketide. Culture fluids from pathogenic, toxin-producing (Tox + ) and nonpathogenic, non-toxin-producing (Tox − ) strains were analyzed directly by gradient high-performance liquid chromatography (HPLC) with photodiode array detection and HPLC-mass spectrometry to detect intermediates and final products of the biosynthetic pathway. This approach allowed us to compare the metabolite profiles of Tox + and Tox − strains. Peritoxins A and B and the biologically inactive intermediates, N -3-( E -pentenyl)-glutaroyl-aspartate, circinatin, and 7-chlorocircinatin, were detected only in culture fluids of the Tox + strains. The latter two compounds were produced consistently by Tox + strains regardless of the amount of peritoxins produced under various culture conditions. In summary, none of the known peritoxin-related metabolites were detected in Tox − strains, which suggests that these strains may lack one or more functional genes required for peritoxin biosynthesis.

The glycolytic enzymes of trypanosomes are attractive drug targets, since the blood-stream form of Trypanosoma brucei lacks a functional citric acid cycle and is dependent solely on glycolysis for its energy requirements. Glyceraldehyde-3-phosphate dehydrogenases (GAPDH) from the pathogenic trypanosomatids T. brucei, Trypanosoma cruzi and Leishmania mexicana are quite similar to each other, and yet have sufficient structural differences compared to the human enzyme to enable the structure-based design of compounds that selectively inhibit all three trypanosomatid enzymes but not the human homologue. Adenosine analogs with substitutions on N-6 of the adenine ring and on the 2′ position of the ribose moiety were designed, synthesized and tested for inhibition. Two crystal structures of L. mexicana glyceraldehyde-3-phosphate dehydrogenase in complex with high-affinity inhibitors that also block parasite growth were solved at a resolution of 2.6 A and 3.0 A. The complexes crystallized in the same crystal form, with one and a half tetramers in the crystallographic asymmetric unit. There is clear electron density for the inhibitor in all six copies of the binding site in each of the two structures. The L. mexicana GAPDH subunit exhibits substantial structural plasticity upon binding the inhibitor. Movements of the protein backbone, in response to inhibitor binding, enlarge a cavity at the binding site to accommodate the inhibitor in a classic example of induced fit. The extensive hydrophobic interactions between the protein and the two substituents on the adenine scaffold of the inhibitor provide a plausible explanation for the high affinity of these inhibitors for trypanosomatid GAPDHs.

Experimental autoimmune encephalomyelitis (EAE) is a T lymphocyte-mediated disease of the central nervous system (CNS), characterized by mononuclear cell infiltration and demyelination resulting in paralysis. We examined CC chemokine expression in the CNS throughout the entire course of the disease and found that the production of macrophage inflammatory protein (MIP)-1alpha correlated with increasing acute disease severity and remained elevated throughout chronic, relapsing disease. In contrast, a substantial level of monocyte chemotactic protein (MCP)-1 expression was not observed until late in acute disease and continued to be evident in the relapsing phase of the disease. MCP-1 expression correlated with increasing severity of clinical relapses. Lower levels of RANTES in the CNS were noted throughout the disease course, but showed little correlation with either acute or relapsing disease. Although RANTES expression was observed during the entire course of disease, anti-RANTES treatment had no effect on clinical disease progression. Anti-MCP-1, but not anti-MIP-1alpha, treatment during relapsing EAE decreased clinical severity of relapsing disease. Furthermore, anti-MCP-1 treatment reduced CNS macrophage accumulation during relapsing EAE. These results suggest that MIP-1alpha controls mononuclear cell accumulation during acute EAE, while MCP-1 controls mononuclear cell infiltration during relapsing EAE.

The Information Age brings enormous benefit to the United States; however, US dependence upon technology results in a new strategic threat aimed at the information systems that control key aspects of our military, economic, and political power. New Strategic Threat Overwhelming US conventional military might suggests that future competitors may embrace grand strategies that avoid directly attacking US defense forces and focus on undermining our national will to fight by exploiting our reliance upon information systems, present technological vulnerability, and the democratic method of governing. This threat would be most effective in situations where US force application is discretionary and the desirability of its employment is not clear-cut. Though it will never equate to the strategic threat of physical occupation by conventional military forces, it is a potent coercive policy weapon. We believe the current US grand strategy for national security is obsolete because: (1) It is based upon industrial age threats and defenses that have limited information age applicability. (2) It fails to defend against structured information attacks threatening US centers of gravity. (3) It is still reliant upon DOD as sole provider of national defense.

Stealth, A Revolutionary Change To Warfare highlights the unique capabilities stealth weapons bring to the battlefield and asserts they offer new and valuable options to the commander. It suggests these capabilities must be fully understood to be fully effective With a focus at the doctrinal level, the paper claims: stealth assets take away from the absolute primacy of aerospace control (air superiority) and in many cases, allows force application to became the primary task. It also asserts; stealth assets expand and enhance the potential opportunities for effective use of air power across the spectrum of warfare to include the force presence role. These and other changes will impact air warfare at all levels. Capitalizing on stealth requires: (1) a recognition of unique stealth attributes; (2) fully embracing these attributes through Air Force doctrinal changes; and (3) a fresh look for potential applications in all operational planning. Revolutionary; Evolutionary; Perspective; Assets; Effectiveness; Doctrine.

The Trail Making Test, used in differentiating brain-damaged from non-brain-damaged individuals, was administered to 150 non-brain-damaged subjects classified into five age decades to determine the effects of age on performance. Between-group comparisons as well as correlational data indicated that older subjects performed significantly more poorly than younger subjects. Significant small negative correlations of performance with education and intelligence suggested that lower intelligence and education also may adversely affect performance. Some implications of these findings for clinical neuropsychology are discussed.