226 research outputs found

    Common messenger molecules and cell types demonstrating neuroendocrine-immune interactions in the chicken

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    The aim of this study was to identify common messenger molecules used in both the immune and the neuroendocrine systems in birds, and to shed light on a cell type within the bursa of Fabricius that has historically been postulated as a potential neuroendocrine-immune link, the bursal secretory dendritic-like cells (BSDC). An immunocytochemical approach was used to identify neuroendocrine cell populations in the thymus, pituitary and bursa of Fabricius in the chicken. Molecular confirmation of the neuroendocrine cell marker, chromogranin A (CgA) in the thymus tissue of the chicken was reported. Previously the serine protease inhibitor, ovoinhibitor, was localized in bursal follicles, specifically the cortico-medullary border region. The presence of ovoinhibitor was identified and confirmed in the chicken pituitary by this study. Continued focus on the neuroendocrine-immune interactions in chicken immune tissue narrowed the study around the BSDC population. The BSDC are a component of the stromal, non-lymphoid cellular environment of the bursa of Fabricius and are thought to play a role in B-cell maturation and differentiation. They are located mainly along the cortico-medullary border of the bursal follicles in the same area as the majority of the ovoinhibitor-positive cell population. During attempts to isolate the BSDC population by flow cytometry and laser capture microdissection, a cell culture method was developed that enriched the BSDC population by 10-fold. This enriched population was used to evaluate protein product secretion following lipopolysaccharide (LPS) challenge and compared to in vivo challenge with live Salmonella. For the first time, up-regulation of the pro-inflammatory cytokine IL-12 was documented in the chicken following in vivo challenge. In addition, the gene expression of serine protease inhibitors was markedly decreased in the adherent cell population following LPS stimulation. As a result of this research a novel method for the enrichment of an adherent population, including the BSDC, was developed, providing a valuable tool for the analysis of this population during immune stimulation

    Culture-Based Environmental Microbiology Monitoring of Crop-Based Space Food Systems (veggie Monitoring)

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    Crewmembers live and work in a closed environment that is monitored to ensure their health and safety. Quarterly monitoring of the microorganisms in the International Space Station (ISS) environment supports crew safety and contributes to a large set of microbial concentration and diversity data from air, surfaces and water samples. This study leverages quarterly operational Environmental Health System (EHS) sampling by collecting additional microbial samples from the surface of the stations Veggie plant production system. Longer exploration missions may require spaceflight-based systems for growth of plants, and this investigation is expected to provide additional data to help establish requirements to protect these systems, plants, and crew, mitigating adverse microbial exposure

    Predicting Invasive Carp Habitat Suitability in the Minnesota River, Minnesota

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    Since the 1980\u27s invasive carp have been expanding their range northward up the Mississippi River. Consisting of four species, grass carp (Ctenophaygodon idella), silver carp (Hypophthalmichthys molitrix), bighead carp (H. nobilis), and black carp (Mylopharyngodon piceus), these fish have the potential to naturalize and expand into large Mississippi River tributaries like the Minnesota River (MNR). Thus, understanding the likelihood of naturalization in these tributaries is vital in guiding prevention or mitigation efforts. This study evaluates the environmental suitability of the Minnesota River, the largest tributary to the Mississippi in Minnesota, for invasive carp. Environmental suitability for invasive carp is modeled using a two-stage framework. The first stage models the climatic suitability of the river with the NicheA model algorithm. The models were then refined using higher resolution MODIS remotely sensed data in the MaxEnt model algorithm. MaxEnt model results were connected to different floodplain inundation levels on the Minnesota River to forecast at risk backwaters. While variable, models forecast suitable habitat for all four species of invasive carp in the Minnesota River watershed. Combined, these data can be used to inform prevention and mitigation strategies for invasive carp management efforts in the Minnesota River watershed

    Negotiating Styles Among American Purchasing Managers In The 21st Century: Revisited

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    This study addresses whether the collaborative negotiation style is the most prevalent among American purchasing managers in the 21st century’s landscape created by the global economy. It also examines whether there are relationships between the purchasing manager’s negotiation styles and selected personal and organizational characteristics that may affect negotiation styles. The results of the study reveal that the collaborative style is predominant. There are also significant relationships between the purchasing manager’s negotiation styles and personal and organizational characteristics

    Risk of Adverse Health Effects Due to Host-Microorganism Interactions

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    While preventive measures limit the presence of many medically significant microorganisms during spaceflight missions, microbial infection of crewmembers cannot be completely prevented. Spaceflight experiments over the past 50 years have demonstrated a unique microbial response to spaceflight culture, although the mechanisms behind those responses and their operational relevance were unclear. In 2007, the operational importance of these microbial responses was emphasized as the results of an experiment aboard STS-115 demonstrated that the enteric pathogen Salmonella enterica serovar Typhimurium (S. Typhimurium) increased in virulence in a murine model of infection. The experiment was reproduced in 2008 aboard STS-123 confirming this finding. In response to these findings, the Institute of Medicine of the National Academies recommended that NASA investigate this risk and its potential impact on the health of the crew during spaceflight. NASA assigned this risk to the Human Research Program. To better understand this risk, evidence has been collected and reported from both spaceflight analog systems and actual spaceflight. Although the performance of virulence studies during spaceflight are challenging and often impractical, additional information has been and continues to be collected to better understand the risk to crew health. Still, the uncertainty concerning the extent and severity of these alterations in host-microorganism interactions is very large and requires more investigation

    Evidence Report: Risk of Adverse Health Effects Due to Host-Microorganism Interactions

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    While preventive measures limit the presence of many medically significant microorganisms during spaceflight missions, microbial infection of crewmembers cannot be completely prevented. Spaceflight experiments over the past 50 years have demonstrated a unique microbial response to spaceflight culture, although the mechanisms behind those responses and their operational relevance were unclear. In 2007, the operational importance of these microbial responses was emphasized as the results of an experiment aboard STS-115 demonstrated that the enteric pathogen Salmonella enterica serovar Typhimurium (S. Typhimurium) increased in virulence in a murine model of infection. The experiment was reproduced in 2008 aboard STS-123 confirming this finding. In response to these findings, the Institute of Medicine of the National Academies recommended that NASA investigate this risk and its potential impact on the health of the crew during spaceflight. NASA assigned this risk to the Human Research Program. To better understand this risk, evidence has been collected and reported from both spaceflight analog systems and actual spaceflight including Mir, Space Shuttle, and ISS missions. Although the performance of virulence studies during spaceflight are challenging and often impractical, additional information has been and continues to be collected to better understand the risk to crew health. Still, the uncertainty concerning the extent and severity of these alterations in host-microorganism interactions is very large and requires more investigation as the focus of human spaceflight shifts to longer-duration exploration class missions

    NASA's Current Evidence and Hypothesis for the Visual Impairment and Intracranial Pressure Risk

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    While 40 years of human spaceflight exploration has reported visual decrement to a certain extent in a subgroup of astronauts, recent data suggests that there is indeed a subset of crewmembers that experience refraction changes (hyperoptic shift), cotton wool spot formation, choroidal fold development, papilledema, optic nerve sheath distention and/or posterior globe flattening with varying degrees of severity and permanence. Pre and postflight ocular measures have identified a potential risk of permanent visual changes as a result of microgravity exposure, which has been defined as the Visual Impairment and Intracranial Pressure risk (VIIP). The combination of symptoms are referred to as the VIIP syndrome. It is thought that the ocular structural and optic nerve changes are caused by events precipitated by the cephalad fluid shift crewmembers experience during long-duration spaceflight. Three important systems, ocular, cardiovascular, and central nervous, seem to be involved in the development of symptoms, but the etiology is still under speculation. It is believed that some crewmembers are more susceptible to these changes due to genetic/anatomical predisposition or lifestyle (fitness) related factors. Future research will focus on determining the etiology of the VIIP syndrome and development of mechanisms to mitigate the spaceflight risk

    Next Generation Microbiology Requirements

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    As humans continue to explore deep into space, microorganisms will travel with them. The primary means to mitigate the risk of infectious disease are a combination of prudent spacecraft design and rigorous operational controls. The effectiveness of these methods are evaluated by microbiological monitoring of spacecraft, food, water, and the crew that is performed preflight, in-flight, and post-flight. Current NASA requirements associated with microbiological monitoring are based on culture-based methodology where microorganisms are grown on a semi-solid growth medium and enumerated. Subsequent identification of the organisms requires specialized labor and large equipment, which historically has been performed on Earth. Requirements that rely strictly on culture-based units limit the use of non-culture based monitoring technology. Specifically, the culture-based "measurement criteria" are Colony Forming Units (CFU, representing the growth of one microorganism at a single location on the agar medium) per a given volume, area, or sample size. As the CFU unit by definition is culture-based, these requirements limit alternative technologies for spaceflight applications. As spaceflight missions such as those to Mars extend further into space, culture-based technology will become difficult to implement due to the (a) limited shelf life of the culture media, (b) mass/volume necessary to carry these consumables, and (c) problems associated with the production of biohazardous material in the habitable volume of the spacecraft. In addition, an extensive amount of new knowledge has been obtained during the Space Shuttle, NASA-Mir, and International Space Station Programs, which gave direction for new or modified microbial control requirements for vehicle design and mission operations. The goal of this task is to develop and recommend a new set of requirements for vehicle design and mission operations, including microbiological monitoring, based upon "lessons learned" and new technology. During 2011, this study focused on evaluating potable water requirements by assembling a forum of internal and external experts from NASA, other federal agencies, and academia. Key findings from this forum included: (1) Preventive design and operational strategies should be stringent and the primary focus of NASA's mitigation efforts, as they are cost effective and can be attained with conventional technology. (2) Microbial monitoring hardware should be simple and must be able to measure the viability of microorganisms in a sample. Multiple monitoring technologies can be utilized as long as at the microorganisms being identified can also be confirmed as viable. (3) Evidence showing alterations in the crew immune function and microbial virulence complicates risk assessments and creates the need for very conservative requirements. (4) One key source of infectious agents will always be the crew, and appropriate preventative measures should be taken preflight. (5) Water systems should be thoroughly disinfected (sterilized if possible) preflight and retain a residual biocide throughout the mission. Future forums will cover requirements for other types of samples, specifically spaceflight food and environmental samples, such as vehicle air and vehicle and cargo surfaces. An interim report on the potable water forum has been delivered to the Human Research Program with a final report on the recommendations for all sample types being delivered in September 2013
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