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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Homogenization of Large-Scale Movement Models in Ecology with Application to the Spread of Chronic Wasting Disease in Mule Deer

Garlick, Martha J. 01 May 2012 (has links)
A difficulty in using diffusion models to predict large-scale animal population dispersal is that individuals move differently based on local information (as opposed to gradients) in differing habitat types. This can be accommodated by using ecological diffusion. However, real environments are often spatially complex, limiting application of a direct approach. Homogenization for partial differential equations has long been applied to Fickian diffusion (in which average individual movement is organized along gradients of habitat and population density). In this work, we derive a homogenization procedure for ecological diffusion, which allows us to determine the impact of small-scale (10-100 m) habitat variability on large-scale (10-100 km) movement, and apply it to models for chronic wasting disease (CWD) in mule deer. CWD is an infectious prion disease that affects members of the Cervidae family. It is a slow-developing, fatal disease, which is rare in the free-ranging deer population of Utah. We first present a simple spatial disease model to illustrate our homogenization procedure and the use of ecological diffusion as a way to connect animal movement with disease spread. Then we develop a more disease-specific sex-structured model for the spread of CWD, incorporating both horizontal and environmental transmission pathways. We apply our homogenization technique to greatly reduce the computational load for a simulation of disease spread from the La Sal Mountains to the Abajo Mountains of Southeast Utah. We use the averaged coefficients from the homogenized model to explore asymptotic invasion speed and critical population size for portions of our study area. Lastly, we describe the estimation of motilities for the disease-specific model from GPS location data, using a continuous-time correlated random walk model.
42

A methodology for determining mass movement susceptibility for land-use planning

Cimmery, Vern Walter 01 January 1976 (has links)
Land-use planning takes into consideration geologic hazards in order to protect both life and property. One type of geologic hazard is mass movement. Mass movement is a collective term for the downslope movement of mass units of debris e.g., bedrock, soil, and subsurface material, resulting from the influence of gravity and involving transporting media such as ice, snow, water, and air. As population increases, further pressures are placed on existing land use. Many areas once considered unsuitable for development due to steep slope or other physical characteristics are now experiencing problems. These areas, due to their physical characteristics, can be susceptible to mass movement. The problem is, information related to the areal distribution of susceptibility is most often not available for input to the land-use planning process. This thesis is proposing a methodology to provide general-level mass movement susceptibility maps. The methodology is a computer application utilizing the Harvard I. M. G. R. l. D. (IMGRID) System. IMGRID is a system using grid cells as the basic units of data storage, analysis, retrieval, and display. Basically, the methodology consists of three major components or phases: (1) providing the computer with data acceptable to the machine and computer programs (input); (2) manipulation of the data and storage of map results within the machine's memory (processing); and (3) the retrieval and display of results (output). The processing of the data is organized around susceptibility models which generate computer maps identifying areas susceptible to mass movements. Areas susceptible to moss movements are defined as portions of the landscape characterized by a set of natural characteristics existing in a stable state which will yield a failure of the material if acted upon by an external or internal triggering event either natural or man-induced. The methodology was applied to a small area in Southwest Washington as a demonstration of how one mechanically follows it from beginning to end. Nine mass movement models were constructed based on the Varnes’ classification system and applied to a data bank containing eleven data variables. The susceptibility mops generated were analyzed to determine the significant mapping classes using the statistical output from IMGRID.
43

A Description of the Use of Portable Ultrasound as a Nutritional Assessment Tool in Kidney Transplant Candidates

Lopez , Gabriella Elizabeth 27 August 2019 (has links)
No description available.
44

Landscape Ecology of Chronic Wasting Disease in Virginia, USA

Winter, Steven Nicholas 10 December 2020 (has links)
Wildlife diseases often occur under quantifiable and consistent patterns, which can be understood to statistically predict their occurrence and spread across landscapes. Chronic wasting disease (CWD) is a neurodegenerative disease in the deer family Cervidae caused by a prion, a pathogenic and misfolded variant of a naturally occurring protein. Managing and controlling CWD is imperative for conservation of ecologically and economically important cervid species, but unclear transmission mechanisms within landscapes complicate evidence-based management. Gaps of information in the landscape ecology for CWD are particularly pronounced for areas with recent disease emergence and spread, such as within the CWD cluster in the Mid-Atlantic United States. Thus, I identified current gaps in information and sought to fill neglected areas of research, specifically focusing on landscape determinants for CWD occurrence and spread in the state of Virginia. In chapter 2, I conducted a scoping study that collected and synthesized decades of CWD research and identified trends with respect to statistical and mathematical modeling methods used, connectivity within the CWD research community, and the geographic areas from which studies were performed. In chapter 3, I investigated landscape determinants for CWD in Virginia using remote sensing landscape data and an epidemiological dataset from Virginia Department of Wildlife Resources (DWR) using diverse algorithms and model evaluation techniques. Finally, in chapter 4, I modeled landscape connectivity between confirmed CWD cases to examine potential paths and barriers to CWD spread across landscapes. My results indicate that landscape ecology was rarely incorporated throughout CWD's 50+ year history. I provide evidence that remotely-sensed landscape conditions can be used to predict the likelihood of CWD occurrence and connectivity in Virginia landscapes, suggesting plausible CWD spread. I suggest areas of future work by explicitly identifying gaps in CWD research and diagnostic methods from which models are based, and encourage further consideration of host's ecology in modeling. By integrating remotely-sensed data into my modeling framework, the workflow should be easily adaptable to new study areas or other wildlife diseases. / Master of Science / Understanding why diseases occur in some locations and not others can be a critical challenge for disease ecologists. One disease that has received significant attention from the media and scientific community is chronic wasting disease (CWD), which is caused by a misfolded protein called a prion. Virginia Department of Wildlife Resources (DWR) has identified a stark increase in the number of CWD cases since first discovered in 2009, which threatens white-tailed deer populations and a 500 million dollar industry used for conservation of Virginia wildlife species. Previous research found that CWD does not occur randomly on the landscape, but otherwise little is known about the landscape ecology of CWD. To provide insight on Virginia's CWD outbreak, I assessed methods used to investigate other CWD outbreaks in both space and time. Also, I used landscape data collected from satellites and data from CWD cases in Virginia, and applied statistical tools to identify patterns in the landscape that were linked with CWD cases. My results suggest that landscapes were rarely examined to understand CWD, and instead, researchers focused on understanding how populations will respond to the disease. I also provide evidence that, at least in Virginia, researchers can use satellite information with disease data to predict CWD on the landscape and estimate its spread. This information can be used by wildlife managers to control the disease. For example, disease surveillance can be increased in areas where CWD has been predicted, or herd sizes can be reduced in areas likely to promote disease spread. This information could also be used to tailor wildlife health regulations aimed to minimize the risk of other deer populations acquiring the disease. Ultimately, the landscape plays an important role in CWD, but research on this topic is limited; therefore, additional research is needed to understand and eventually control this disease affecting ecologically and culturally important game species.
45

Genetic Stability of a Genetically-Engineered Chimeric Porcine Circovirus (PCV) Vaccine, PCV1-2

Gillespie, Jennifer Ann 04 June 2009 (has links)
Porcine circovirus type 2 (PCV2) is the primary causative agent of porcine circovirus associated disease (PCVAD), an economically important swine disease that causes wasting in pigs 5-18 weeks of age. There exist two different types of porcine circoviruses: porcine circovirus type 1 (PCV1) was discovered as a contaminant of porcine kidney (PK-15) cells and was determined to be nonpathogenic in swine; whereas porcine circovirus type 2 (PCV2) is pathogenic. A recently released vaccine for PCVAD was generated by inserting the gene encoding the immunogenic capsid protein of PCV2 into the genetic backbone of the non-pathogenic PCV1. This chimeric PCV vaccine, called PCV1-2, was shown to induce protective immunity against PCV2 infection in pigs. The vaccine is currently on the market in a killed form. In order to develop a live version of the vaccine, the genetic stability of the chimeric PCV1-2 vaccine virus was investigated by in vitro and in vivo passaging of the vaccine virus. In vitro passaging of the PCV1-2 vaccine virus was done in a porcine kidney PK-15 cell line. Cells were infected with the PCV1-2 vaccine virus and then serially passaged 11 times. The passaged vaccine viruses recovered from passages 5 and 11 were sequenced, and the sequences were compared to that of the original PCV1-2 vaccine virus. The in vitro serial passage result showed that no mutation occurred during the 11 in vitro passages. The in vivo passaging was done using specific-pathogen-free (SPF) pigs. In in vivo "passage 1", nine piglets were divided into 3 groups of 3 each: group 1 each inoculated with 200ug of PCV1-2 plasmid, group 2 each with 1Ã 103 TCID50 live PCV1-2 vaccine virus, and group 3 each with 3ml phosphate buffered saline (PBS) buffer as a control. One pig from each group was necropsied at 14, 21, and 28 days post-inoculation (DPI), respectively. A panel of tissue samples including lymph nodes and thymus were collected from each pig. Tissue homogenates from DPI 28 that were positive by PCR for PCV1-2 DNA were used to inoculate new piglets in the in vivo passage 2 experiment. Viruses recovered from passage 2 pigs were subsequently used for inoculation in the in vivo passage 3 experiment. The PCV1-2 vaccine virus DNA from pigs in each passage was amplified and sequenced. The results of the in vivo serial passage experiment showed that, after 3 passages of the PCV1-2 vaccine virus in pigs, there were no new mutations in the viruses recovered from pigs. The PCV1-2 vaccine contained an introduced marker mutation at amino acid position number 79, which is in the capsid region. During the in vivo passaging of the vaccine virus in pigs, this marker mutation quickly reverted back to its original nucleotide. This marker back mutation occurred between DPI 21 and DPI 28 of passage 1 in the PCV1-2 live vaccine virus group, and between DPI 28 of passage 1 and DPI 14 of passage 2 in the PCV1-2 vaccine plasmid group, and remained stable throughout the reminder of the in vivo study. Based upon the results from this study, we conclude that the PCV1-2 chimeric vaccine virus is genetically stable in vitro and in pigs, and thus should serve as a good candidate for a live vaccine against PCV2. / Master of Science
46

Etude des conséquences de l’activation de la voie imd au cours de la métamorphose et la vie adulte de la drosophile / Consequences of imd pathway activation during metamorphosis and adult life of drosophila

Tavignot, Raphaël 19 October 2018 (has links)
Au cours d’une infection, l’intensité et la durée de la réaction immunitaire doivent être étroitement contrôlées au risque de devenir délétère pour l’hôte. Chez la drosophile Drosophila Melanogaster, une infection bactérienne conduit à l’activation de voies de signalisation de type NFκ-B, conservées au cours de l'évolution, via la détection du peptidoglycane, un composant de la paroi bactérienne, par des récepteurs PGRPs (« Peptidoglycan Recognition Proteins »). Durant ma thèse, j’ai étudié les conséquences d’une activation non contrôlée d'une de ces voies, la voie IMD, sur la physiologie de la drosophile. Le premier projet auquel j’ai participé montre que l’inactivation de PGRP-LF, un régulateur négatif de la voie, conduit à l'activation de la voie IMD dans les tissus larvaires dérivés de l’ectoderme en absence d’infection. Cette activation entraine l’expression ectopique dans ces tissus de la protéines DIAP1 («Drosophila Inhibitor of Apoptosis 1»), suffisante pour induire la malformation de certains tissus de la drosophile adulte démontrant une fonction développementale jusqu'alors inconnue de la voie IMD au cours de la métamorphose de la drosophile. Dans la seconde partie de ma thèse, j’ai pu observer que durant une infection chronique, le maintien de l’activation de la voie IMD entraine l’apparition de nombreux phénotypes tels qu’une baisse de l’espérance de vie, des troubles locomoteurs, de la neurodégénérescence et l’atrophie du corps gras et des ovaires. Mes résultats montrent que l’activation de la voie IMD spécifiquement au niveau de la glie périneuriale, un composant de la barrière hématoencéphalique, participe activement à l’apparition des phénotypes observés. / Upon infection, the intensity and duration of the immune response must be tightly controlled at the risk of becoming harmful for the host. In the fruit fly Drosophila Melanogaster, a bacterial infection leads to the activation of evolutionary conserved NFk-B signalling pathways, through detection of a bacterial cell wall component, the peptidoglycan (PG), by PGRPs ("Peptidoglycan Recognition Proteins") receptors. During my thesis, I studied the consequences of uncontrolled activation of one of these NFk-B pathways, the IMD pathway, on the physiology of Drosophila. The first project I took part in shows that inactivation of PGRP-LF, a negative regulator of the pathway, leads to the activation of the IMD pathway in ectodermal derived larval tissues without any infection. This pathway activation in those tissues leads to an ectopic expression of the DIAP1 ("Drosophila Inhibitor of Apoptosis 1") protein, wich is sufficient to induce some adult Drosophila structures malformations, demonstrating a previously unknown developmental function of the IMD pathway during Drosophila metamorphosis. In the second part of my thesis, I was able to demonstrate that during chronic infection, maintenance of IMD pathway activation leads to the appearance of many deleterious phenotypes such as a decreased lifespan, locomotor disorders, neurodegeneration and atrophy of the fat body and ovaries. My results show that IMD pathway activation specifically in the perineurial glia, a component of the blood-brain barrier, actively contributes to the development of the observed phenotypes. Demonstrating for the first time that fhe fly's brain is able to detect circulating PG in the hemolymph.
47

Erhebung von Blutrichtwerten und deren Beeinflussung durch Haltung und Fütterung beim Weißbüschelaffen (Callithrix jacchus)

Kühnel, Friederike 27 November 2013 (has links) (PDF)
Weißbüschelaffen (WBA) sind wissenschaftlich häufig genutzte Modelltiere für diverse Humanerkrankungen. Zur Gesunderhaltung dieser Primaten sind grundlegende diagnostische Blutparameter unverzichtbar. Bisher erhobene Daten zeichneten sich jedoch durch große Divergenz aus. Ob Veränderungen in Haltungsbedingungen einen Einfluss auf diese Blutparameter nehmen, ist bis heute unklar. Somit war ein Ziel dieser Arbeit die Erhebung aktueller hämatologischer und klinisch-chemischer Blutparameter von WBA. Zudem wurde der Einfluss der routinemäßigen Umsetzung in eine neue Behausung auf die erhobenen Parameter sowie den Kortisolspiegel im Kot untersucht. Des Weiteren leiden WBA in menschlicher Obhut rezidivierend an gastrointestinalen Erkrankungen, die mittels klinischer Standardparameter allein nicht diagnostizierbar sind. Dabei spielt vor allem die Sensitivität gegenüber Futtermittelinhaltsstoffen (z. B. Gluten) eine Rolle, welche ursächlich im Zusammenhang mit dem Wasting Marmoset Syndrome (WMS) diskutiert wird. Im zweiten Teil der vorliegenden Arbeit sollten deshalb die gastrointestinalen Erkrankungen von in menschlicher Obhut lebenden WBA ätiologisch beleuchtet werden, vor allem hinsichtlich einer möglichen Sensitivität gegenüber Gluten. Im ersten Teil dieser Studie wurden von 54 WBA hämatologische und klinischchemische Richtwerte erhoben. Die ermittelten hämatologischen Blutrichtwerte ähneln denen aus den achtziger Jahren, die Daten der klinischen Chemie nur bedingt: Die Richtwertbereiche von Laktatdehydrogenase, Alaninaminotransferase, Lipase sowie Alkalische Phosphatase und Gesamtbilirubin weichen von den ehemals erhobenen Daten ab. Zudem wurden in der vorliegenden Arbeit geschlechtsabhängige Unterschiede ermittelt: Weibliche Tiere wiesen signifikant höheres mittleres Erythrozytenvolumen und mittleren Hämoglobingehalt des Einzelerythrozyten auf als männliche Tiere, wohingegen bei diesen ein signifikant höheres Gesamt- und Low density lipoprotein- Cholesterol im Vergleich zu weiblichen Affen messbar war. Des Weiteren wurden 16 Tiere über einen vierwöchigen Zeitraum in eine neue Umgebung verbracht, bevor sie in ihre Heimatbehausung zurückkehrten. Durch diese Umsetzung war bei den untersuchten Tieren die Leuko- und Lymphozytenzahl auch vier Wochen nach der Umsetzung erniedrigt. Zeitgleich lag ein erhöhter Kortisolspiegel vor, der im Kot bestimmt wurde. Im zweiten Teil der Studie wurden anhand humandiagnostischer Standards IgAAntikörper (AK) gegen Gliadin (AGA), Gewebstransglutaminase (tTG), deamidiertes Gliadin (ADGA) sowie Glykoprotein 2 (AGP2A) im Plasma von 24 WBA mittels eines ELISAs während glutenhaltiger (Diät 1) und glutenfreier Ernährung (Diät 2) bestimmt. Dabei wurden die klinische Symptomatik von WMS und das Körpergewicht der Tiere ebenfalls untersucht. Zudem erfolgte die Analyse von Kotproben antikörperpositiver Tiere hinsichtlich Qualität und Trockenmassegehalt während Diät 2 und einer darauf folgenden glutenhaltigen Provokationsdiät. Die serologische Diagnostik ergab einen signifikanten Rückgang von AGA, AK gegen tTG und AGP2A während Diät 2 bei Tieren, die nach Diät 1 erhöhte Werte aufwiesen. Diät 2 führte zu einem Rückgang der klinischen Symptome und einer signifikanten Gewichtszunahme bei antikörperpositiven WBA. Die glutenhaltige Provokationsdiät ergab eine verminderte Kotqualität mit einem niedrigeren Trockenmassegehalt. Es wurden im Rahmen dieser Arbeit aktuelle, hämatologische und klinisch-chemische Blutrichtwerte des WBA erhoben. Der durch Umsetzung in eine neue Behausung bedingte Stress ist bei WBA bis vier Wochen lang nachweisbar. Es ist sinnvoll, dies in der zeitlichen Planung wissenschaftlicher Studien zu berücksichtigen, um das Wohlbefinden der Tiere vor Versuchsbeginn sicherzustellen und den Einfluss von Stress auf experimentelle Ergebnisse zu minimieren. Der Nachweis grundlegender, an der Pathogenese der Zöliakie beteiligter Antikörper, in Kombination mit den klinischen Symptomen, deutet auf Glutensensitivität mit ätiologischer Beteiligung an WMS bei WBA hin. Die glutenfreie Ernährung von WBA in menschlicher Obhut ist daher sinnvoll und empfehlenswert. / Common marmosets are often used as animal models for human diseases. For their health maintenance, diagnostic blood values are absolutely essential. Previously obtained reference values are characterized by great value-specific differences. Moreover, the influence of routine measures on these blood parameters, e. g. changes in housing conditions, has not been examined yet. Therefore, the first aim of the present study was to update haematological and clinical chemical blood parameters of common marmosets. Further, the influence of stress, caused by relocation to a new housing, on these parameters and the cortisol level in feces was examined. In addition to that, common marmosets under human management are often affected by gastrointestinal diseases, which are difficult to diagnose with basic standard blood values. In this context, sensitivity to nutritional elements, e. g. gluten, plays an important role and is discussed as a potential cause of wasting marmoset syndrome (WMS). In the second part of this study, the recurrent gastrointestinal diseases of common marmosets under human management were aetiologically investigated, with special regard to possible gluten sensitivity. In the first part of this study, blood samples were obtained from 54 female and male common marmosets to evaluate standard values of haematology and clinical chemistry. The determined haematological parameters are similar to the already obtained data, the clinical chemistry values differ somewhat: The enzyme activities of lactate dehydrogenase, alanine aminotransferase and lipase in addition to the ranges of alkaline phosphatase and total bilirubin diverge from the data ascertained in this study. Moreover, female animals presented significantly higher mean corpuscular volume and mean corpuscular haemoglobin than males, whereas male common marmosets showed significantly higher total- and low density lipoprotein-cholesterol, compared to females. Further, 16 animals were relocated to a new environment for a time period of four weeks, before they returned to their home cages. The change of housing caused a decreased leuko- and lymphocyte count in all examined animals that was still measurable four weeks after the relocation. At the same time, an increased fecal cortisol level was determined. The aim of the second study was to investigate the modification of plasma antibodies to gliadin (AGA), tissue transglutaminase (tTG), deamidated gliadin (ADGA) and glycoprotein 2 (AGP2A) during two successive diets in 24 animals: A gluten-containing diet (diet 1) and a gluten-free diet (diet 2). Further, clinical symptoms of WMS and the animals’ body weight were also examined. An analysis of the feces of antibody-positive animals regarding changes in quality and dry matter content was carried out with samples collected during diet 2 and a successive gluten challenge diet of two months duration. The serological diagnostics resulted in a significant decline of AGA, antibodies to tTG and AGP2A during diet 2 in animals that had shown increased antibody concentrations during diet 1. Diet 2 also caused an amelioration of clinical symptoms and an increased body weight in antibody-positive animals. The gluten challenge resulted in a decreased feces quality and a lower fecal dry matter, compared to fecal samples of diet 2. In the context of this dissertation, parameters of haematology and clinical chemistry of the common marmoset were updated. Stress caused by relocation to a new housing was still measurable for a period of four weeks. It is therefore essential to consider this time span in the design of scientific studies to secure animal welfare prior to the study and to reduce the influence of stress on experimental results. In combination with the clinical symptoms, the detection of antibodies that are part of the pathogenesis of coeliac disease in humans strongly suggests gluten sensitivity with an aetiological connection to WMS in common marmosets. Therefore, gluten-free nutrition of common marmosets under human management is highly recommendable.
48

Erhebung von Blutrichtwerten und deren Beeinflussung durch Haltung und Fütterung beim Weißbüschelaffen (Callithrix jacchus)

Kühnel, Friederike 05 November 2013 (has links)
Weißbüschelaffen (WBA) sind wissenschaftlich häufig genutzte Modelltiere für diverse Humanerkrankungen. Zur Gesunderhaltung dieser Primaten sind grundlegende diagnostische Blutparameter unverzichtbar. Bisher erhobene Daten zeichneten sich jedoch durch große Divergenz aus. Ob Veränderungen in Haltungsbedingungen einen Einfluss auf diese Blutparameter nehmen, ist bis heute unklar. Somit war ein Ziel dieser Arbeit die Erhebung aktueller hämatologischer und klinisch-chemischer Blutparameter von WBA. Zudem wurde der Einfluss der routinemäßigen Umsetzung in eine neue Behausung auf die erhobenen Parameter sowie den Kortisolspiegel im Kot untersucht. Des Weiteren leiden WBA in menschlicher Obhut rezidivierend an gastrointestinalen Erkrankungen, die mittels klinischer Standardparameter allein nicht diagnostizierbar sind. Dabei spielt vor allem die Sensitivität gegenüber Futtermittelinhaltsstoffen (z. B. Gluten) eine Rolle, welche ursächlich im Zusammenhang mit dem Wasting Marmoset Syndrome (WMS) diskutiert wird. Im zweiten Teil der vorliegenden Arbeit sollten deshalb die gastrointestinalen Erkrankungen von in menschlicher Obhut lebenden WBA ätiologisch beleuchtet werden, vor allem hinsichtlich einer möglichen Sensitivität gegenüber Gluten. Im ersten Teil dieser Studie wurden von 54 WBA hämatologische und klinischchemische Richtwerte erhoben. Die ermittelten hämatologischen Blutrichtwerte ähneln denen aus den achtziger Jahren, die Daten der klinischen Chemie nur bedingt: Die Richtwertbereiche von Laktatdehydrogenase, Alaninaminotransferase, Lipase sowie Alkalische Phosphatase und Gesamtbilirubin weichen von den ehemals erhobenen Daten ab. Zudem wurden in der vorliegenden Arbeit geschlechtsabhängige Unterschiede ermittelt: Weibliche Tiere wiesen signifikant höheres mittleres Erythrozytenvolumen und mittleren Hämoglobingehalt des Einzelerythrozyten auf als männliche Tiere, wohingegen bei diesen ein signifikant höheres Gesamt- und Low density lipoprotein- Cholesterol im Vergleich zu weiblichen Affen messbar war. Des Weiteren wurden 16 Tiere über einen vierwöchigen Zeitraum in eine neue Umgebung verbracht, bevor sie in ihre Heimatbehausung zurückkehrten. Durch diese Umsetzung war bei den untersuchten Tieren die Leuko- und Lymphozytenzahl auch vier Wochen nach der Umsetzung erniedrigt. Zeitgleich lag ein erhöhter Kortisolspiegel vor, der im Kot bestimmt wurde. Im zweiten Teil der Studie wurden anhand humandiagnostischer Standards IgAAntikörper (AK) gegen Gliadin (AGA), Gewebstransglutaminase (tTG), deamidiertes Gliadin (ADGA) sowie Glykoprotein 2 (AGP2A) im Plasma von 24 WBA mittels eines ELISAs während glutenhaltiger (Diät 1) und glutenfreier Ernährung (Diät 2) bestimmt. Dabei wurden die klinische Symptomatik von WMS und das Körpergewicht der Tiere ebenfalls untersucht. Zudem erfolgte die Analyse von Kotproben antikörperpositiver Tiere hinsichtlich Qualität und Trockenmassegehalt während Diät 2 und einer darauf folgenden glutenhaltigen Provokationsdiät. Die serologische Diagnostik ergab einen signifikanten Rückgang von AGA, AK gegen tTG und AGP2A während Diät 2 bei Tieren, die nach Diät 1 erhöhte Werte aufwiesen. Diät 2 führte zu einem Rückgang der klinischen Symptome und einer signifikanten Gewichtszunahme bei antikörperpositiven WBA. Die glutenhaltige Provokationsdiät ergab eine verminderte Kotqualität mit einem niedrigeren Trockenmassegehalt. Es wurden im Rahmen dieser Arbeit aktuelle, hämatologische und klinisch-chemische Blutrichtwerte des WBA erhoben. Der durch Umsetzung in eine neue Behausung bedingte Stress ist bei WBA bis vier Wochen lang nachweisbar. Es ist sinnvoll, dies in der zeitlichen Planung wissenschaftlicher Studien zu berücksichtigen, um das Wohlbefinden der Tiere vor Versuchsbeginn sicherzustellen und den Einfluss von Stress auf experimentelle Ergebnisse zu minimieren. Der Nachweis grundlegender, an der Pathogenese der Zöliakie beteiligter Antikörper, in Kombination mit den klinischen Symptomen, deutet auf Glutensensitivität mit ätiologischer Beteiligung an WMS bei WBA hin. Die glutenfreie Ernährung von WBA in menschlicher Obhut ist daher sinnvoll und empfehlenswert. / Common marmosets are often used as animal models for human diseases. For their health maintenance, diagnostic blood values are absolutely essential. Previously obtained reference values are characterized by great value-specific differences. Moreover, the influence of routine measures on these blood parameters, e. g. changes in housing conditions, has not been examined yet. Therefore, the first aim of the present study was to update haematological and clinical chemical blood parameters of common marmosets. Further, the influence of stress, caused by relocation to a new housing, on these parameters and the cortisol level in feces was examined. In addition to that, common marmosets under human management are often affected by gastrointestinal diseases, which are difficult to diagnose with basic standard blood values. In this context, sensitivity to nutritional elements, e. g. gluten, plays an important role and is discussed as a potential cause of wasting marmoset syndrome (WMS). In the second part of this study, the recurrent gastrointestinal diseases of common marmosets under human management were aetiologically investigated, with special regard to possible gluten sensitivity. In the first part of this study, blood samples were obtained from 54 female and male common marmosets to evaluate standard values of haematology and clinical chemistry. The determined haematological parameters are similar to the already obtained data, the clinical chemistry values differ somewhat: The enzyme activities of lactate dehydrogenase, alanine aminotransferase and lipase in addition to the ranges of alkaline phosphatase and total bilirubin diverge from the data ascertained in this study. Moreover, female animals presented significantly higher mean corpuscular volume and mean corpuscular haemoglobin than males, whereas male common marmosets showed significantly higher total- and low density lipoprotein-cholesterol, compared to females. Further, 16 animals were relocated to a new environment for a time period of four weeks, before they returned to their home cages. The change of housing caused a decreased leuko- and lymphocyte count in all examined animals that was still measurable four weeks after the relocation. At the same time, an increased fecal cortisol level was determined. The aim of the second study was to investigate the modification of plasma antibodies to gliadin (AGA), tissue transglutaminase (tTG), deamidated gliadin (ADGA) and glycoprotein 2 (AGP2A) during two successive diets in 24 animals: A gluten-containing diet (diet 1) and a gluten-free diet (diet 2). Further, clinical symptoms of WMS and the animals’ body weight were also examined. An analysis of the feces of antibody-positive animals regarding changes in quality and dry matter content was carried out with samples collected during diet 2 and a successive gluten challenge diet of two months duration. The serological diagnostics resulted in a significant decline of AGA, antibodies to tTG and AGP2A during diet 2 in animals that had shown increased antibody concentrations during diet 1. Diet 2 also caused an amelioration of clinical symptoms and an increased body weight in antibody-positive animals. The gluten challenge resulted in a decreased feces quality and a lower fecal dry matter, compared to fecal samples of diet 2. In the context of this dissertation, parameters of haematology and clinical chemistry of the common marmoset were updated. Stress caused by relocation to a new housing was still measurable for a period of four weeks. It is therefore essential to consider this time span in the design of scientific studies to secure animal welfare prior to the study and to reduce the influence of stress on experimental results. In combination with the clinical symptoms, the detection of antibodies that are part of the pathogenesis of coeliac disease in humans strongly suggests gluten sensitivity with an aetiological connection to WMS in common marmosets. Therefore, gluten-free nutrition of common marmosets under human management is highly recommendable.
49

Examining the Impact of Household Access to Water and Sanitation on Child Malnutrition in Ethiopia

Wondimu, Mehiret 09 August 2016 (has links)
Introduction: Millions of children worldwide die before they reach their fifth birthday. Approximately 50% of all deaths in children are associated with malnutrition. Although remarkable improvements have been seen in the past few decades, child malnutrition remains a major public health problem in Ethiopia. Malnutrition has been linked to various morbidities and as the underlying cause of 57% of mortality in the country. It is caused by complex and multidimensional biological, social economic, and environmental factors. There are scarce literatures examining the environmental factors, such as access to water and sanitation, on the likelihood of child malnutrition as measured by stunting, wasting, and underweight in Ethiopia, which the current study sought to investigate. Aim: The primary aim of this study was to examine the relationship between households’ access to water and sanitation facilities and the likelihood that a child will become stunted or wasted or underweight. Methods: The study utilized a nationally representative data from 2011 Ethiopia Demographic and Health Survey. The sample size was 9,611 children aged 0-59 months. A weighted descriptive statistical analysis was performed to examine the frequency distribution of the study’s primary independent variables (sanitation and water), dependent variables (childhood stunting, wasting, and underweight), and all other variables included in the study. Weighted bivariate analysis was conducted using logistic regression to quantify association between stunting, wasting, and being underweight and different independent variables. Weighted multivariate logistic regression analysis was performed to control for potential confounders while examining the relationship between the primary independent and dependent variables. Odds ratios, 95% confidence limits, and p-value were calculated. We considered three sets of potential confounders: child’s (child’s gender, child’s age, and child’s size at birth diarrheal disease, fever), maternal (maternal education) and household characteristics (maternal BMI, place of residence, wealth index, stool disposal, time to get water). Only variables that showed significant association (p-value Main results: Approximately 44%, 10%, and 29% of the children under-five years of age were stunted, wasted, and underweight, respectively. About 54% of the study population used unimproved source of drinking water and about 82% used unimproved sanitation facility. Our bivariate logistic analysis revealed that children in households with unimproved source of drinking water had higher odds of stunting compared to children in households with improved drinking water source (OR: 1.2; 95% CL 1.02-1.34). Adjustment for child’s characteristics yielded AOR: 1.2; 95% CL 1.0-1.4. Addition of maternal characteristics attenuated this association (AOR: 1.1; 95% CL 1.0-1.3 1.0; 95% CL 0.8-1.2). Finally, inclusion of household characteristics showed stunting was not associated with unimproved source of drinking water (AOR: 1.0; 95% 0.8-1.2). The bivariate analysis revealed household access to unimproved source of drinking water was not significantly associated with wasting (OR: 1.0; 95% CL 0.8-1.3) and underweight (OR: 1.2; 95% CL 1.0-1.4). Adjustment of child, maternal, and household characteristic showed an inverse association between source of drinking water and wasting (AOR: 0.7; 95% CL 0.6-0.9). In the bivariate analysis, access to unimproved sanitation was significantly associated with stunting (OR: 1.3; 95% CL 1.02-1.74) and underweight (OR: 1.5; 95% CL 1.1-2.1). Compared to children living in homes with access to improved sanitation facility, children in household with unimproved sanitation facility had 1.4 increased odds of being stunted (95% CL 1.1-1.9) after adjustment for child’s characteristics. Adjustment of child, maternal, and household characteristics attenuated this association (AOR: 1.1; 95% CL 0.8-1.5). Children in household with unimproved sanitation facility had higher odds of being underweight after adjusting for child characteristics (AOR: 1.6; 95% CL 1.2-2.2). Addition of maternal characteristic reduced the association (AOR: 1.5; 95% CL 1.1-2.0). Finally, the addition of household characteristics further attenuated this association (AOR: 1.4; 95% CL 1.1-1.9). Children from households with improved water but unimproved sanitation had higher odds of wasting and being underweight compared to children living in household with both services: AORs adjusted for child’s characteristics were 2.3 (95% CL 1.3-4.3) for wasting and 2.4 (95% CL 1.6-3.6) for underweight; when maternal characteristics were included, AORs were 2.2 (95% CL 1.2-4.1) and 2.1 (95% 1.4-3.3) for wasting and underweight, correspondingly; finally, when household characteristics were included AORs were 2.0 (95% CL 1.1-3.9) and 1.9 (95% CL 1.2-3.0), respectively. Conclusion: Our results suggest that household access to unimproved source of drinking water and sanitation increase the likelihood of malnutrition. Therefore, initiatives to increase access to improved sources of drinking water and sanitation facilities along with nutritional intervention could help alleviate the high burden of malnutrition in Ethiopia.
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O envolvimento do proteossomo na perda muscular de modelo de artrite induzida por colágeno e o efeito do tratamento com inibidor do fator de necrose tumoral

Teixeira, Vivian de Oliveira Nunes January 2015 (has links)
Introdução: A artrite reumatoide é uma doença inflamatória autoimune associada à complicações sistêmicas como fadiga e perda muscular. Perda muscular pode estar relacionada com a ativação do sistema ubiquitina-proteossomo. O objetivo deste trabalho foi avaliar a perda muscular e o evolvimento do proteossomo no modelo de artrite induzida por colágeno (CIA), com ou sem o tratamento de metotrexato ou inibidor de TNF (etanercepte). Métodos: Camundongos DBA1/J machos foram divididos em 4 grupos (n=8 cada): CIA (salina); ETN (etanercepte, 5.5 /) e MTX (metotrexato, 35 /), tratados duas vezes por semana por 6 semanas, e um grupo controle saudável (CO). Tratamentos iniciaram uma semana após a injeção do booster. Escore clínico, edema da pata traseira e peso corporal foram analisados durante o período experimental. Músculo gastrocnêmio (GA) foi pesado após a morte e usado para quantificar a atividade, níveis proteicos e expressão de mRNA das diferentes subunidades do proteossomo através de ensaio fluorogênico, Western blot e rtPCR, respectivamente. Resultados: Tratamentos reduziram o desenvolvimento da doença, observado através do menor escore clínico e edema da pata traseira nos grupos ETN e MTX. ETN apresentou maior peso corporal do que MTX nas semanas 5 e 7. Músculo GA estava aumentado em ETN do que CIA e MTX, um resultado também observado no peso muscular normalizado. As propriedades catalíticas do proteossomo 26S muscular mostraram um aumento na atividade do tipo caspase nos grupos CIA e MTX. Tecidos musculares de animais MTX demonstraram maiores níveis proteicos das subunidades do proteossomo PSMB8 e PSMB9 e maior expressão gênica de Psmb5, Psmb8 e Psmb9. Por outro lado, a expressão de Psmb6 estava diminuída e de Psmb9 estava aumentada em CIA. Conclusões: Apesar de ambos os medicamentos melhorarem o escore da doença, ETN apresentou um afeito anti-artrítico mais forte e foi o único tratamento capaz de prevenir parcialmente a perda muscular. Ao contrário de ETN, CIA e o tratamento com MTX apresentaram perda muscular e atividade e expressão do proteossomo aumentadas. / Background: Rheumatoid arthritis is an autoimmune inflammatory disease associated with systemic complications like fatigue and muscle wasting. Muscle wasting could be related to the activation of the ubiquitin-proteasome system. The aim of this study was to evaluate muscle loss and involvement of the proteasome in collagen-induced arthritis (CIA), with or without treatment with methotrexate or a TNF inhibitor (etanercept). Methods: Male DBA1/J mice were divided into 4 groups (n=8 each): CIA (saline); ETN (etanercept, 5.5 /) and MTX (methotrexate, 35 /), treated twice a week for 6 weeks, and a healthy control group (CO). Treatments started one week after booster injection. Clinical score, hind paw oedema, and body weight were analysed during the experimental period. Gastrocnemius muscles (GA) were weighted after death and used to quantify proteasome activity, protein levels and mRNA expression of its subunits by Western blot and rtPCR, respectively. Results: Treatments slowed disease development, observed through smaller clinical score and hindpaw edema in ETN and MTX groups. ETN presented higher body weight compared to MTX group at weeks 5 and 7. GA weight was heavier in ETN than CIA and MTX, a result also observed in the normalized muscle weight. The catalytic properties of 26S proteasome showed an increase of caspase-like activity in CIA and MTX groups. Muscles tissues of MTX treated animals showed higher protein levels for proteasomal subunits PSMB8 and PSMB9 and higher gene expression for Psmb5, Psmb8 and Psmb9. In contrast, expression of Psmb6 was decreased and of Psmb9 was enhanced in CIA. Conclusions: Although both drugs improved the disease score, ETN presented a stronger anti-arthritic effect and was the only treatment able to partially prevent muscle wasting. In contrast to ETN, CIA and MTX treatment did not prevent muscles loss due to increased proteasome expression and activity.

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