bluuebunny/crossref_metadata_2025_split huggingface dataset:
IS5 inserts upstream of the master motility operon flhDC in a quasi-Lamarckian way
Authors: Wang Xiaoxue , Wood Thomas K 
Published: March 2011

Abstract
Mutation rates may be influenced by the environment. Here, we demonstrate that insertion sequence IS5 in Escherichia coli inserts into the upstream region of the flhDC operon in a manner that depends on whether the environment permits motility; this operon encodes the master regulator of cell motility, FlhDC, and the IS5 insertion increases motility. IS5 inserts upstream of flhD+ when cells are grown on soft-agar plates that permit swimming motility, but does not insert upstream of this locus on hard-agar plates that do not permit swimming motility or in planktonic cultures. Furthermore, there was only one IS5 insertion event on soft-agar plates, indicating insertion of IS5 into flhDC is not due to general elevated IS5 transposition throughout the whole genome. We also show that the highly motile cells with IS5 upstream of flhD+ have greater biofilm formation, although there is a growth cost due to the energetic burden of the enhanced motility as these highly motile cells have a lower yield in rich medium and reduced growth rate. Functional flagella are required for IS5 insertion upstream of flhD+ as there was no IS5 insertion upstream of flhD+ for flhD, flgK and motA mutants, and the mutation is stable. Additionally, the IS5 mutation occurs during biofilm formation, which creates genetic and phenotypic diversity. Hence, the cells appear to ‘sense’ whether motility is feasible before a sub-population undergoes a mutation to become hypermotile; this sensing appears related to the master transcription regulator, FlhDC.
Reversal in competitive dominance of a toxic versus non-toxic cyanobacterium in response to rising CO2
Authors: Van de Waal Dedmer B , Verspagen Jolanda M H , Finke Jan F , Vournazou Vasiliki , Immers Anne K , Kardinaal W Edwin A , Tonk Linda , Becker Sven , Van Donk Ellen , Visser Petra M , Huisman Jef 
Published: March 2011

Abstract
Climate change scenarios predict a doubling of the atmospheric CO2 concentration by the end of this century. Yet, how rising CO2 will affect the species composition of aquatic microbial communities is still largely an open question. In this study, we develop a resource competition model to investigate competition for dissolved inorganic carbon in dense algal blooms. The model predicts how dynamic changes in carbon chemistry, pH and light conditions during bloom development feed back on competing phytoplankton species. We test the model predictions in chemostat experiments with monocultures and mixtures of a toxic and non-toxic strain of the freshwater cyanobacterium Microcystis aeruginosa. The toxic strain was able to reduce dissolved CO2 to lower concentrations than the non-toxic strain, and became dominant in competition at low CO2 levels. Conversely, the non-toxic strain could grow at lower light levels, and became dominant in competition at high CO2 levels but low light availability. The model captured the observed reversal in competitive dominance, and was quantitatively in good agreement with the results of the competition experiments. To assess whether microcystins might have a role in this reversal of competitive dominance, we performed further competition experiments with the wild-type strain M. aeruginosa PCC 7806 and its mcyB mutant impaired in microcystin production. The microcystin-producing wild type had a strong selective advantage at low CO2 levels but not at high CO2 levels. Our results thus demonstrate both in theory and experiment that rising CO2 levels can alter the community composition and toxicity of harmful algal blooms.
The Economics of Grain Price Volatility
Authors: Wright Brian D. 
Published: March 2011

AbstractRecent volatility of prices of major grains has generated a wide array of analyses and policy prescriptions that reveal the inability of economists to approach a consensus on the nature of the phenomenon and its implications for policy. This review of market events and their economic interpretations finds that recent price spikes are not as unusual as many discussions imply. Further, the balance between consumption, available supply, and stocks seems to be as relevant for our understanding of these markets as it was decades ago. Though there is much to be learned about commodity markets, the tools at hand are capable of explaining the main forces at work, and of giving good guidance to policymakers confronted with a bewildering variety of expensive policy prescriptions.
Uncertainties in projecting spatial distributions of marine populations
Authors: Planque Benjamin , Bellier Edwige , Loots Christophe 
Published: March 2011

Abstract
Planque, B., Bellier, E., and Loots, C. 2011. Uncertainties in projecting spatial distributions of marine populations. – ICES Journal of Marine Science, 68: 1045–1050. Projection of future spatial distributions of marine populations is a central issue for ecologists and managers. The measure of projection uncertainty is particularly important, because projections can only be useful if they are given with a known and sufficiently high level of confidence. Uncertainties can arise for the observation process, conceptual and numerical model formulations, parameter estimates, model evaluation, appropriate consideration of spatial and temporal scales, and finally the potential of adaptation of living systems. Comprehensive analyses of these multiple sources of uncertainty have not been carried out so far, and how these uncertainties are considered in current studies has not yet been described. To analyse how these different sources of uncertainty are currently considered in marine research, we did a survey of published literature during the period 2005–2009. From the 75 publications selected, we calculated how frequently each type of uncertainty was considered. We found that little attention is given to most sources of uncertainty, except for uncertainty in parameter estimates. As a result, most current projections are expected to be far less reliable than usually assumed. The conclusion is that, unless uncertainty can be better accounted for, such projections may be of limited use, or even risky to use for management purposes.
A general equilibrium model for Atlantic herring (Clupea harengus) with ecosystem considerations
Authors: Kirkley James E. , Walden John , Färe Rolf 
Published: March 2011

Abstract
Kirkley, J. E., Walden, J., and Färe, R. 2011. A general equilibrium model for Atlantic herring (Clupea harengus) with ecosystem considerations. – ICES Journal of Marine Science, 68: 860–866. A framework is presented for assessing the economic ramifications of ecosystem-based management decisions, with attention focused on Atlantic herring (Clupea harengus) in New England. The Atlantic herring has often been referred to as the most important fish in the northeastern United States because it is a filter-feeder, is believed to improve water quality, and is very important to the health, growth, and abundance of major gamefish, marine mammals, seabirds, and several species of fish. Although many approaches for examining the potential economic ramifications of ecosystem-based management are possible, attention is focused on one method that can be used given existing data. A static, deterministic input/output (I/O) optimization (IOLP, input/output linear programming) model is developed that breaks out the impact of different decisions on herring allocation on the 2006 New England regional economy of Maine, New Hampshire, Massachusetts, and Rhode Island. The IOLP model is a promising approach for informing policy-makers of the economic implications of various allocation choices. The framework is also flexible enough to allow further disaggregation of the small model presented to include additional fishing and non-fishing sectors.
Toll-Like Receptor 4 Inhibitor TAK-242 Attenuates Acute Kidney Injury in Endotoxemic Sheep
Authors: Fenhammar Johan , Rundgren Mats , Forestier Jakob , Kalman Sigridur , Eriksson Stefan , Frithiof Robert 
Published: March 2011

Background
This study was conducted to investigate the role of toll-like receptor 4 (TLR4) in mediating acute kidney injury in endotoxemic sheep using the selective TLR4 inhibitor TAK-242.

Methods
A randomized, controlled, experimental study was performed with 20 adult Texel crossbred sheep. Before an Escherichia coli lipopolysaccharide infusion (3 μg · kg(-1) · h(-1) for 24 h), sheep were randomized to receive a bolus dose (2 mg/kg), followed by a continuous infusion (4 mg · kg(-1) · 24 h(-1)) of either TAK-242 (n = 7) or vehicle (n = 7). A third group of lipopolysaccharide-treated sheep (n = 6) received norepinephrine, titrated to maintain baseline arterial blood pressure.

Results
Endotoxin infusion established a state of hyperdynamic circulation, with an increased cardiac index, hypotension, and tachycardia. Urine output and creatinine clearance decreased throughout the experiment, together with increasing plasma creatinine, blood urea nitrogen, and arterial lactate concentrations. After 24 h, TLR4 inhibition had significantly (P ≤ 0.001) attenuated the mean ± SEM decrease in arterial pressure (97 ± 3 vs. 71 ± 4 mmHg), urine output (1.16 ± 0.15 vs. 0.13 ± 0.05 ml · kg(-1) · h(-1)), and creatinine clearance (126 ± 13 vs. 20 ± 7 ml/min) compared with vehicle-treated animals. Furthermore, arterial lactate, plasma creatinine, and blood urea nitrogen concentrations were significantly lower in the TAK-242 group versus the vehicle-treated animals. Compared with TLR4 inhibition, norepinephrine caused similar effects on arterial pressure, cardiac index, and heart rate; however, it did not attenuate the decrease in urine output or creatinine clearance.

Conclusions
These results indicate a critical role for TLR4 in impairing renal function during ovine endotoxemia that is independent of changes in central hemodynamics.
Fertility considerations and preservation in haemato‐oncology patients undergoing treatment
Authors: Leader Avi , Lishner Michael , Michaeli Jennia , Revel Ariel 
Published: March 2011

SummaryThe improved survival rates among patients with haematological malignancies, such as lymphoma and leukaemia, are shifting areas of focus towards understanding and preventing treatment‐induced sequelae. Of these, infertility is one of the most devastating consequences for patients with reproductive potential. The degree of treatment‐induced gonadal dysfunction depends on age and gender‐related differences, the type and dosage of chemotherapy used and the field and cumulative dose of abdomino‐pelvic irradiation. There is also the interesting phenomenon of reduced pre‐treatment fertility among male lymphoma patients. At present, the only established methods of fertility preservation are cryopreservation of sperm, oocytes and embryos, as well as gonadal shielding and transposition of ovaries during irradiation. Several other methods, such as cryopreservation and subsequent transplantation of gonadal tissue and the gonadoprotective role of hormonal suppression, are under investigation. Pre‐pubertal patients present a unique constellation of fertility considerations, especially as embryo and sperm cryopreservation are not applicable to this age group.
Human immunodeficiency virus associated thrombotic thrombocytopenic purpura – favourable outcome with plasma exchange and prompt initiation of highly active antiretroviral therapy
Authors: Hart Daniel , Sayer Ruth , Miller Robert , Edwards Simon , Kelly Anne , Baglin Trevor , Hunt Beverley , Benjamin Sylvia , Patel Raj , Machin Samuel , Scully Marie 
Published: March 2011

SummaryThrombotic thrombocytopenic purpura (TTP) is an acute prothrombotic disorder. Human immunodeficiency virus (HIV) is an identified precipitant. This study reviewed 30 episodes of HIV‐associated TTP in 24 patients from the South‐East England Apheresis units, over the last 10 years. All patients were heterosexual Black Africans. First presentation of TTP revealed a new diagnosis of HIV in eight patients. TTP relapse occurred on six occasions (in four patients) as a result of non‐adherence to highly active antiretroviral therapy (HAART). Prompt initiation/re‐initiation of HAART in parallel with plasma exchange (PEX) ± steroid led to prompt remission. Adjunct immunomodulatory agents (e.g. Rituximab) were required in 10% of cases. Once‐daily HAART regimens are recommended, being compatible with PEX requirement, maximizing drug exposure between PEX. High viral loads (>500 000 copies/ml) require more PEX to remission. ADAMTS13 activity was reduced (<5%) as detected by collagen‐binding assay and anti‐ADAMTS13 immunoglobulin G antibodies were raised in 80%. Continued HAART‐adherence ensured a durable TTP remission with associated viral control resulting in no evidence of relapse. PEX and HAART are associated with replenishment of ADAMTS13 and viral suppression. More PEX is required in cases with higher viral loads. Continued HAART maintains remission. In a small proportion of cases, further immunomodulatory therapy may be required.
Sublingual therapeutic immunization with a polyvalent bacterial preparation in patients with recurrent respiratory infections: immunomodulatory effect on antigen-specific memory CD4+ T cells and impact on clinical outcome
Authors: Alecsandru D , Valor L , Sánchez-Ramón S , Gil J , Carbone J , Navarro J , Rodríguez J J , Rodríguez-Sainz C , Fernández-Cruz E 
Published: March 2011

SummaryRecurrent respiratory tract infections (RRTIs) are common clinical conditions in individuals with alterations of the immune function. A prospective open pilot study in a cohort of patients with RRTIs has been performed to assess whether sublingual immunization with a polyvalent bacterial vaccine could exert an immunomodulatory effect on the antigen-specific immunological responses and have an impact on the clinical outcome. Seventeen patients with RRTIs were recruited. An oral polyvalent bacterial preparation (Bactek®) was administered to all patients daily for 6 months. Immunological assessment was performed at baseline and at the end of immunization. Immunological measurements included: T cell-specific proliferations of CD3+CD4+ and CD3+CD8+ to Bactek® antigens, total immunoglobulin levels, antibodies to pneumococcal polysaccharide and tetanus toxoid and B, T and natural killer (NK) cell subsets. There was a significant increase in the proliferative capacity of CD3+CD4+ T cells specific to Bactek® antigens at month 6 in comparison to baseline (P &lt; 0·0001). A significant increase in total CD3+ T cells was also observed (P &lt; 0·05). No significant differences were observed between baseline and month 6 in levels of total immunoglobulins, specific antibodies and B, T or NK cell subsets. A significant reduction in the patient's rate of RRTIs was observed compared with 1 year prior to initiation of therapy (P &lt; 0·0001). The results demonstrate that long-term administration of a sublingual polyvalent bacterial preparation in patients with RRTIs exerts an immune stimulating effect on CD4+ T helper cell responses to bacterial antigens which could be associated with clinical benefit.
Ursolic acid promotes robust tolerance to cardiac allografts in mice
Authors: Liu Y , Huang X , Li Y , Li C , Hu X , Xue C , Meng F , Zhou P 
Published: March 2011

SummaryNuclear factor (NF)-κB is an important molecule in T cell activation. Our previous work has found that T cell-restricted NF-κB super-repressor (IκBαΔN-Tg) mice, expressing an inhibitor of NF-κB restricted to the T cell compartment, can permanently accept fully allogeneic cardiac grafts and secondary donor skin grafts. In this study, we explore if transient NF-κB inhibition by a small molecular inhibitor could induce permanent graft survival. Ursolic acid, a small molecular compound, dose-dependently inhibited T cell receptor (TCR)-triggered NF-κB nuclear translocation and T cell activation in vitro. In vivo, ursolic acid monotherapy prolonged significantly the survival of cardiac allograft in mice. Assisted with donor-specific transfusion (DST) on day 0, ursolic acid promoted 84·6% of first cardiac grafts to survive for more than 150 days. While the mice with long-term surviving grafts (LTS) did not reject the second donor strain hearts for more than 100 days without any treatment, they all promptly rejected the third-party strain hearts within 14 days. Interestingly, this protocol did not result in an increased proportion of CD4+CD25+forkhead box P3+ regulatory T cells in splenocytes. That adoptive transfer experiments also did not support regulation was the main mechanism in this model. Splenocytes from LTS showed reduced alloreactivity to donor antigen. However, depletion of CD4+CD25+ regulatory T cells did not alter the donor-reactivity of LTS splenocytes. These data suggest that depletion of donor-reactive T cells may play an important role in this protocol.
Pentraxin 3 (PTX3) is associated with cardiovascular risk factors: the Health 2000 Survey
Authors: Jylhävä J , Haarala A , Kähönen M , Lehtimäki T , Jula A , Moilanen L , Kesäniemi Y A , Nieminen M S , Hurme M 
Published: March 2011

Summary
Pentraxin 3 (PTX3) is a novel candidate immunoinflammatory marker that has been reported to be associated with cardiometabolic risk factors and to predict adverse outcomes in individuals with cardiovascular disease (CVD). Despite being a member of the same pentraxin protein family as C-reactive protein (CRP), PTX3 probably reflects different aspects of CVD pathogenesis. In this study, we assessed plasma PTX3 correlates and determinants in the Health 2000 Survey population, which comprised n = 403 insulin-resistant subjects, n = 845 hypercholesterolaemic subjects and n = 311 hypertensive subjects, all aged between 46 and 76 years. In insulin-resistant subjects the PTX3 concentration was found to correlate directly with age, pulse pressure and indoleamine 2,3-dioxygenase (IDO) enzyme activity and inversely with total and low-density lipoprotein (LDL) cholesterol. In hypercholesterolaemic subjects, the PTX3 concentration correlated directly with HDL cholesterol, systolic blood pressure and pulse pressure, whereas in hypertensive subjects, the PTX3 concentration correlated directly with systolic blood pressure, pulse pressure and IDO activity. No correlation was observed between the concentrations of PTX3 and CRP, adiposity indicators or indicators of subclinical atherosclerosis in any of the subject groups. PTX3 concentration variations were attributed to variations in LDL cholesterol and IDO activity in insulin-resistant subjects and to pulse pressure in hypercholesterolaemic and hypertensive subjects. These results indicate that, in individuals at high risk of CVD, the PTX3 concentration is associated with cardiovascular risk factors but not with subclinical atherosclerosis.
Activation of natural killer T cells by α-carba-GalCer (RCAI-56), a novel synthetic glycolipid ligand, suppresses murine collagen-induced arthritis
Authors: Yoshiga Y , Goto D , Segawa S , Horikoshi M , Hayashi T , Matsumoto I , Ito S , Taniguchi M , Sumida T 
Published: March 2011

SummaryAlpha-carba-GalCer (RCAI-56), a novel synthetic analogue of α-galactosylceramide (α-GalCer), stimulates invariant natural killer T (NK T) cells to produce interferon (IFN)-γ. IFN-γ exhibits immunoregulatory properties in autoimmune diseases by suppressing T helper (Th)-17 cell differentiation and inducing regulatory T cells and apoptosis of autoreactive T cells. Here, we investigated the protective effects of α-carba-GalCer on collagen-induced arthritis (CIA) in mice. First, we confirmed that α-carba-GalCer selectively induced IFN-γ in CIA-susceptible DBA/1 mice in vivo. Then, DBA/1 mice were immunized with bovine type II collagen (CII) and α-carba-GalCer. The incidence and clinical score of CIA were significantly lower in α-carba-GalCer-treated mice. Anti-IFN-γ antibodies abolished the beneficial effects of α-carba-GalCer, suggesting that α-carba-GalCer ameliorated CIA in an IFN-γ-dependent manner. Treatment with α-carba-GalCer reduced anti-CII antibody production [immunoglobulin (Ig)G and IgG2a] and CII-reactive interleukin (IL)-17 production by draining lymph node (DLN) cells, did not induce apoptosis or regulatory T cells, and significantly increased the ratio of the percentage of IFN-γ-producing T cells to IL-17-producing T cells (Th1/Th17 ratio). Moreover, the gene expression levels of IL-6 and IL-23p19, Th17-related cytokines, were reduced significantly in mice treated with α-carba-GalCer. In addition, we observed higher IFN-γ production by NK T cells in α-carba-GalCer-treated mice in the initial phase of CIA. These findings indicate that α-carba-GalCer polarizes the T cell response toward Th1 and suppresses Th17 differentiation or activation, suggesting that α-carba-GalCer, a novel NK T cell ligand, can potentially provide protection against Th17-mediated autoimmune arthritis by enhancing the Th1 response.
Modulation of M2 muscarinic receptor–receptor interaction by immunoglobulin G antibodies from Chagas' disease patients
Authors: Beltrame S P , Auger S R , Bilder C R , Waldner C I , Goin J C 
Published: March 2011

SummaryCirculating immunoglobulin (Ig)G antibodies against M2 muscarinic acetylcholine receptors (M2 mAChR) have been implicated in Chagas' disease (ChD) pathophysiology. These antibodies bind to and activate their target receptor, displaying agonist-like activity through an unclear mechanism. This study tested the ability of serum anti-M2 mAChR antibodies from chronic ChD patients to modulate M2 muscarinic receptor–receptor interaction by bioluminescence resonance energy transfer (BRET). Human embryonic kidney (HEK) 293 cells co-expressing fusion proteins M2 mAChR-Renilla luciferase (RLuc) and M2 mAChR-yellow fluorescent protein (YFP) were exposed to the serum IgG fraction from ChD patients, and BRET between RLuc and YFP was assessed by luminometry. Unlike serum IgG from healthy subjects and conventional muscarinic ligands, ChD IgG promoted a time- and concentration-dependent increase in the BRET signal. This effect neither required cellular integrity nor occurred as a consequence of receptor activation. Enhancement of M2 receptor–receptor interaction by ChD IgG was receptor subtype-specific and mediated by the recognition of the second extracellular loop of the M2 mAChR. The monovalent Fab fragment derived from ChD IgG was unable to reproduce the effect of the native immunoglobulin. However, addition of ChD Fab in the presence of anti-human Fab IgG restored BRET-enhancing activity. These data suggest that the modulatory effect of ChD IgG on M2 receptor–receptor interaction results from receptor cross-linking by bivalent antibodies.
Agrobacterium‐mediated transformation of the barley pathogen Ramularia collo‐cygni with fluorescent marker tags and live tissue imaging of infection development
Authors: Thirugnanasambandam A. , Wright K. M. , Havis N. , Whisson S. C. , Newton A. C. 
Published: March 2011

Ramularia collo‐cygni, the causal agent of ramularia leaf spot disease in barley was transformed to express the green fluorescent protein and DsRed fluorescent protein using a combined protoplast and Agrobacterium tumefaciens‐mediated transformation technique. Regenerated protoplasts from mycelial fragments were transformed with A. tumefaciens strain AGL1 containing either pCAMBgfp or pCAMBDsRed plasmids. Two different isolates of R. collo‐cygni were transformed and several stable transformants were recovered. These transformants infected detached barley leaves and characteristic swan’s‐neck‐shaped conidiophores were seen on detached leaves 9 days after inoculation, as well as spore‐like structures formed from hyphal swellings. This first successful transformation of R. collo‐cygni has enabled better description of the stages of disease development and pathogen behaviour during the endophytic/asymptomatic stage of its life cycle.