184 research outputs found

    Cryptosporidium Priming Is More Effective than Vaccine for Protection against Cryptosporidiosis in a Murine Protein Malnutrition Model

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    Cryptosporidium is a major cause of severe diarrhea, especially in malnourished children. Using a murine model of C. parvum oocyst challenge that recapitulates clinical features of severe cryptosporidiosis during malnutrition, we interrogated the effect of protein malnutrition (PM) on primary and secondary responses to C. parvum challenge, and tested the differential ability of mucosal priming strategies to overcome the PM-induced susceptibility. We determined that while PM fundamentally alters systemic and mucosal primary immune responses to Cryptosporidium, priming with C. parvum (106 oocysts) provides robust protective immunity against re-challenge despite ongoing PM. C. parvum priming restores mucosal Th1-type effectors (CD3+CD8+CD103+ T-cells) and cytokines (IFNγ, and IL12p40) that otherwise decrease with ongoing PM. Vaccination strategies with Cryptosporidium antigens expressed in the S. Typhi vector 908htr, however, do not enhance Th1-type responses to C. parvum challenge during PM, even though vaccination strongly boosts immunity in challenged fully nourished hosts. Remote non-specific exposures to the attenuated S. Typhi vector alone or the TLR9 agonist CpG ODN-1668 can partially attenuate C. parvum severity during PM, but neither as effectively as viable C. parvum priming. We conclude that although PM interferes with basal and vaccine-boosted immune responses to C. parvum, sustained reductions in disease severity are possible through mucosal activators of host defenses, and specifically C. parvum priming can elicit impressively robust Th1-type protective immunity despite ongoing protein malnutrition. These findings add insight into potential correlates of Cryptosporidium immunity and future vaccine strategies in malnourished children

    Persistent G. lamblia impairs growth in a murine malnutrition model

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    Giardia lamblia infections are nearly universal among children in low-income countries and are syndemic with the triumvirate of malnutrition, diarrhea, and developmental growth delays. Amidst the morass of early childhood enteropathogen exposures in these populations, G. lamblia-specific associations with persistent diarrhea, cognitive deficits, stunting, and nutrient deficiencies have demonstrated conflicting results, placing endemic pediatric giardiasis in a state of equipoise. Many infections in endemic settings appear to be asymptomatic/subclinical, further contributing to uncertainty regarding a causal link between G. lamblia infection and developmental delay. We used G. lamblia H3 cyst infection in a weaned mouse model of malnutrition to demonstrate that persistent giardiasis leads to epithelial cell apoptosis and crypt hyperplasia. Infection was associated with a Th2-biased inflammatory response and impaired growth. Malnutrition accentuated the severity of these growth decrements. Faltering malnourished mice exhibited impaired compensatory responses following infection and demonstrated an absence of crypt hyperplasia and subsequently blunted villus architecture. Concomitantly, severe malnutrition prevented increases in B220+ cells in the lamina propria as well as mucosal Il4 and Il5 mRNA in response to infection. These findings add insight into the potential role of G. lamblia as a "stunting" pathogen and suggest that, similarly, malnourished children may be at increased risk of G. lamblia-potentiated growth decrements

    "Barriers" to Child Development and Human Potential: The Case for Including the "Neglected Enteric Protozoa" (NEP) and Other Enteropathy-Associated Pathogens in the NTDs

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    The World Health Organization (WHO) has set forth ambitious efforts to control, and where possible, eliminate the neglected tropical diseases (NTDs) that contribute to poverty and ‘‘impair the ability of those infected to achieve their full potential, both developmentally and socioeconomically’’ [1,2]. This neglected disease initiative’s (NDI) purpose has been to close the existing poverty gap between individuals living in low/middle-income and high-income countries, and thus facilitate the achievement of the 2000 Millennium Developmental Goals [3]. The gap is still large. Yet, some marked achievements of the NDI, including coordinated administration of preventive chemotherapy to nearly 670 million children globally and the imminent elimination of dracunculiasis, give hope that the WHO’s NTD paradigm, a ‘‘five-pronged’’ approach of 1) preventive chemotherapy, 2) intensified case-management, 3) vector control, 4) provision of safe water, sanitation, and hygiene, and 5) veterinary public health, are proving beneficia

    Virtual coatings application system

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    A virtual coatings application system has several features to enhance the realism of simulated spray painting. The system generally includes a display screen on which is defined a virtual surface (such as a truck door) that is intended to be virtually painted or coated by the user. Alternatively, the system includes a head-mounted display unit that displays a virtual spray painting environment in which the virtual surface is defined. The user operates an instrumented spray gun controller that outputs one or more signals representing data as to the status of the controls on the spray gun controller. The system also has a motion tracking system that tracks the position and orientation of the spray gun controller with respect to the virtual surface. Simulation software generates virtual spray pattern data in response to at least the data from the spray gun controller and the position and orientation data received from the tracking system. Virtual spray pattern images are displayed in real time on the virtual surface in accordance with the accumulation of virtual spray pattern data at each location on the virtual surface

    Virtual coatings application system

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    A virtual coatings application system has several features to enhance the realism of simulated spray painting. The system generally includes a display screen on which is defined a virtual surface (such as a truck door) that is intended to be virtually painted or coated by the user. The user operates an instrumented spray gun controller that outputs one or more signals representing data as to the status of the controls on the spray gun controller. The system also has a motion tracking system that tracks the position and orientation of the spray gun controller with respect to the virtual surface defined on the display screen. Simulation software generates virtual spray pattern data in response to at least the data from the spray gun controller and the position and orientation data received from the tracking system. Virtual spray pattern images are displayed in real time on the display screen in accordance with the accumulation of virtual spray pattern data at each location on the virtual surface

    Investigation of a monoclonal antibody against enterotoxigenic Escherichia coli, expressed as secretory IgA1 and IgA2 in plants.

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    Passive immunization with antibodies is a promising approach against enterotoxigenic Escherichia coli diarrhea, a prevalent disease in LMICs. The objective of this study was to investigate expression of a monoclonal anti-ETEC CfaE secretory IgA antibody in N. benthamiana plants, with a view to facilitating access to ETEC passive immunotherapy. SIgA1 and SIgA2 forms of mAb 68-81 were produced by co-expressing the light and engineered heavy chains with J chain and secretory component in N. benthamiana. Antibody expression and assembly were compared with CHO-derived antibodies by SDS-PAGE, western blotting, size-exclusion chromatography and LC-MS peptide mapping. N-linked glycosylation was assessed by rapid fluorescence/mass spectrometry and LC-ESI-MS. Susceptibility to gastric digestion was assessed in an in vitro model. Antibody function was compared for antigen binding, a Caco-2 cell-based ETEC adhesion assay, an ETEC hemagglutination inhibition assay and a murine in vivo challenge study. SIgA1 assembly appeared superior to SIgA2 in plants. Both sub-classes exhibited resistance to degradation by simulated gastric fluid, comparable to CHO-produced 68-61 SIgA1. The plant expressed SIgAs had more homogeneous N-glycosylation than CHO-derived SIgAs, but no alteration of in vitro functional activity was observed, including antibodies expressed in a plant line engineered for mammalian-like N glycosylation. The plant-derived SIgA2 mAb demonstrated protection against diarrhea in a murine infection model. Although antibody yield and purification need to be optimized, anti-ETEC SIgA antibodies produced in a low-cost plant platform are functionally equivalent to CHO antibodies, and provide promise for passive immunotherapy in LMICs

    A multi-stage genome-wide association study of bladder cancer identifies multiple susceptibility loci.

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    We conducted a multi-stage, genome-wide association study of bladder cancer with a primary scan of 591,637 SNPs in 3,532 affected individuals (cases) and 5,120 controls of European descent from five studies followed by a replication strategy, which included 8,382 cases and 48,275 controls from 16 studies. In a combined analysis, we identified three new regions associated with bladder cancer on chromosomes 22q13.1, 19q12 and 2q37.1: rs1014971, (P = 8 × 10⁻¹²) maps to a non-genic region of chromosome 22q13.1, rs8102137 (P = 2 × 10⁻¹¹) on 19q12 maps to CCNE1 and rs11892031 (P = 1 × 10⁻⁷) maps to the UGT1A cluster on 2q37.1. We confirmed four previously identified genome-wide associations on chromosomes 3q28, 4p16.3, 8q24.21 and 8q24.3, validated previous candidate associations for the GSTM1 deletion (P = 4 × 10⁻¹¹) and a tag SNP for NAT2 acetylation status (P = 4 × 10⁻¹¹), and found interactions with smoking in both regions. Our findings on common variants associated with bladder cancer risk should provide new insights into the mechanisms of carcinogenesis

    A multi-stage genome-wide association study of bladder cancer identifies multiple susceptibility loci.

    Get PDF
    We conducted a multi-stage, genome-wide association study of bladder cancer with a primary scan of 591,637 SNPs in 3,532 affected individuals (cases) and 5,120 controls of European descent from five studies followed by a replication strategy, which included 8,382 cases and 48,275 controls from 16 studies. In a combined analysis, we identified three new regions associated with bladder cancer on chromosomes 22q13.1, 19q12 and 2q37.1: rs1014971, (P = 8 × 10⁻¹²) maps to a non-genic region of chromosome 22q13.1, rs8102137 (P = 2 × 10⁻¹¹) on 19q12 maps to CCNE1 and rs11892031 (P = 1 × 10⁻⁷) maps to the UGT1A cluster on 2q37.1. We confirmed four previously identified genome-wide associations on chromosomes 3q28, 4p16.3, 8q24.21 and 8q24.3, validated previous candidate associations for the GSTM1 deletion (P = 4 × 10⁻¹¹) and a tag SNP for NAT2 acetylation status (P = 4 × 10⁻¹¹), and found interactions with smoking in both regions. Our findings on common variants associated with bladder cancer risk should provide new insights into the mechanisms of carcinogenesis

    Adenosine receptors differentially mediate enteric glial cell death induced by Clostridioides difficile Toxins A and B

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    Increased risk of intestinal dysfunction has been reported in patients after Clostridioides difficile infection (CDI). Enteric glial cells (EGCs), a component of the enteric nervous system (ENS), contribute to gut homeostasis. Previous studies showed that adenosine receptors, A2A and A2B, modulate inflammation during CDI. However, it is unknown how these receptors can modulate the EGC response to the C. difficile toxins (TcdA and TcdB). We investigated the effects of these toxins on the expression of adenosine receptors in EGCs and the role of these receptors on toxin-induced EGC death. Rat EGCs line were incubated with TcdA or TcdB alone or in combination with adenosine analogues 1h prior to toxins challenge. After incubation, EGCs were collected to evaluate gene expression (adenosine receptors and proinflammatory markers) and cell death. In vivo, WT, A2A, and A2B KO mice were infected with C. difficile, euthanized on day 3 post-infection, and cecum tissue was processed. TcdA and TcdB increased A2A and A3 transcripts, as well as decreased A2B. A2A agonist, but not A2A antagonist, decreased apoptosis induced by TcdA and TcdB in EGCs. A2B blocker, but not A2B agonist, diminished apoptosis in EGCs challenged with both toxins. A3 agonist, but not A3 blocker, reduced apoptosis in EGCs challenged with TcdA and TcdB. Inhibition of protein kinase A (PKA) and CREB, both involved in the main signaling pathway driven by activation of adenosine receptors, decreased EGC apoptosis induced by both toxins. A2A agonist and A2B antagonist decreased S100B upregulation induced by C. difficile toxins in EGCs. In vivo, infected A2B KO mice, but not A2A, exhibited a decrease in cell death, including EGCs and enteric neuron loss, compared to infected WT mice, reduced intestinal damage and decreased IL-6 and S100B levels in cecum. Our findings indicate that upregulation of A2A and A3 and downregulation of A2B in EGCs and downregulation of A2B in intestinal tissues elicit a protective response against C. difficile toxins. Adenosine receptors appear to play a regulatory role in EGCs death and proinflammatory response induced by TcdA and TcdB, and thus may be potential targets of intervention to prevent post-CDI intestinal dysmotility

    Breast cancer survival in the US and Europe: a CONCORD high-resolution study.

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    Breast cancer survival is reportedly higher in the US than in Europe. The first worldwide study (CONCORD) found wide international differences in age-standardized survival. The aim of this study is to explain these survival differences. Population-based data on stage at diagnosis, diagnostic procedures, treatment and follow-up were collected for about 20,000 women diagnosed with breast cancer aged 15-99 years during 1996-98 in 7 US states and 12 European countries. Age-standardized net survival and the excess hazard of death up to 5 years after diagnosis were estimated by jurisdiction (registry, country, European region), age and stage with flexible parametric models. Breast cancers were generally less advanced in the US than in Europe. Stage also varied less between US states than between European jurisdictions. Early, node-negative tumors were more frequent in the US (39%) than in Europe (32%), while locally advanced tumors were twice as frequent in Europe (8%), and metastatic tumors of similar frequency (5-6%). Net survival in Northern, Western and Southern Europe (81-84%) was similar to that in the US (84%), but lower in Eastern Europe (69%). For the first 3 years after diagnosis the mean excess hazard was higher in Eastern Europe than elsewhere: the difference was most marked for women aged 70-99 years, and mainly confined to women with locally advanced or metastatic tumors. Differences in breast cancer survival between Europe and the US in the late 1990s were mainly explained by lower survival in Eastern Europe, where low healthcare expenditure may have constrained the quality of treatment
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