Sök:

Sökresultat:

233 Uppsatser om Toxic Escherichia coli-genes - Sida 13 av 16

Blood compatibility of biomaterials made of recombinant spider silk

Native spider silk is an attractive lightweight natural polymeric material with a unique combination of strength, extendibility and flexibility. Synthetic, recombinant spider silk is an attractive biomaterial with several possible fields of application. When a foreign material is introduced to blood, this can for example cause unwanted coagulation and complement activation. The aim of this study was to investigate if coatings of heparin or albumin could improve the blood compatibility of films of recombinant spider silk and to develop an initial method to do so. Hypothetically, objects like pacemakers, stents and dental implants could be covered with spider silk films of high blood compatibility to reduce potentially harmful foreign body reactions caused by the immune defense. Increased blood compatibility would likely lead to improvements for both the individual patients and the society thanks to reduced load on healthcare institutions. Our objective was to assess the blood compatibility of both functionalized and non-functionalized recombinant spider silk by evaluating coagulation and activation of the complement system of the immune defense. Coagulation was evaluated visually on glass slides and complement activation was analyzed by measuring the concentration of the complement system mediator C3a in blood samples that had been exposed to the different materials. This study introduces a non-toxic and easy performed method of improving the blood compatibility of recombinant spider silk films by adding a heparin coating. Heparin coated surfaces had statistically significantly higher blood compatibility than uncoated surfaces. The effects of albumin coating of films were less clear compared to the results of heparin coated films. Complement activation could not be evaluated because of high activation in all samples prior contact with the materials that were included in the study..

Spridning av släckvattenpartiklar : En studie på spridning av partiklar genererade från brand

During a fire large amounts of particles and unhealthy agents occur.  Polyaromatic hydrocarbons (PAH) and toxic metals are examples among many others. These agents have a capacity to bond to particles and when the fire is extinguished, the particles can be transferred with the extinguish water into the soil and to the groundwater.Recent studies in particles have been conducted. A study by Ulrika Iverfelt (2014) reviled that the particles from a fire contained large amounts of both PAH and metals, which is consistent with earlier analyses. Her column experiments with particles in the size ? 11 microns and ?100 microns in silica sand, reviled that the larger particles was immobilized because the transportation was influenced by sieving or physiochemical particle and surface interactions.The transport of the particles in soil and groundwater is regulated by two main mechanisms: physiochemical surface interactions and straining.

Species diversity and geographical distribution of Fusarium species on winter wheat in two regions in Sweden

Various Fusarium species causes some of the most common cereal diseases worldwide. Besides the yield losses that can be a result of these diseases, strains from several Fusarium species can produce mycotoxins, some very toxic. The aim of this study was to investigate which Fusarium species and how many that occurred in winter wheat grains from Mälardalen and Kalmar län, if there was any difference in the distribution of Fusarium fungi between the regions and the potential within species to produce mycotoxins belonging to the group trichothecenes. Winter wheat grains collected in 2009 from ten fields (unsprayed plots) in the two regions were analysed for Fusarium species. PCR was used to amplify the TEF region where after the samples were sequenced.

Biosensorsystem fo?r o?vervakning av vattenkvalitet

Sweden's drinking water quality is considered to be high partly due to a high quality of the raw water and a well developed sewage infrastructure. Despite this, there is water contamination that could be prevented by installation of a sophisticated early warning system. Some of the major players in the production of drinking water have already invested in different types of early warning systems to ensure drinking water of high quality. There are various forms of early warning systems where automatic monitoring of E. Coli is an interesting alternative.

Fermentation of lignocellulosic material by the alternative industrial ethanol yeast Dekkera bruxellensis

Bioethanol is one alternative energy fuel that can be produced from different types of biomass. Second generation bioethanol comes from fermentation of lignocellulosic material and can be seen as a more environmental friendly alternative as e.g. forest residues and agricultural by-products are used. To be able to use lignocellulosic biomass in ethanol production, it has to be subjected to different treatments first. In this study, aspen sawdust was used as lignocellulosic material.

Inappetens hos katt ? omvårdnadsbehandlingar med fokus på beröring

Particular to the cat among our pets is its´ unique nutritional needs and metabolism. The cat cannot produce some nutrients by themselves and must get them through their diet. This means that the cat quickly can suffer from various diseases unless the nutritional needs are covered. In those cases where man is completely in control of the cat?s diet, the right knowledge is crucial for the cat?s wellbeing.

Växters förmåga att ackumulera metaller : Vass, bredkaveldun och gäddnate i Bergviks dagvattendamm

AbstractSurface-water includes different kinds of pollutants from traffic and roads. To prevent these pollutants to reach nearby lakes one can construct surface-water ponds on locations with heavy traffic. At Bergviks shopping centre in Karlstad, two ponds, one smaller and one bigger has been constructed in order to decrease the pollutant pressure from the receiving waters of Kattfjorden. Several heavy metals are essential for plants and animals in low concentration but when they occur in higher concentrations, they become toxic to the organism. The larger pond at Bergviks shopping centre has a sedimentation function so the heavy metals sink to the bottom thereby not releasing directly in to Kattfjorden.

Molekylärgenetisk analys av dilaterad cardiomyopati hos hund :

Canine dilated cardiomyopathy (DCM) is a disease with high morbidity and mortality and with a high prevalence in certain breeds. Predominatly large breeds are affected, such as Great danes, Newfoundlands, Deerhounds and Dobermanns. One exception is Cocker spaniels, where both American and English Cocker spaniels are affected in a quite high frequency. Cardiomyopathy is characterised as a disease that affects the myocardium and gives an impaired heart function. To diagnose DCM following criteria have to be observed: 1. Dilation of the left ventricle. 2. Reduced systolic heart function. 3. Increased sphericity of the left ventricle. To be certain of the diagnosis, alternative reasons for the symptoms such as lung- and heart diseases with other etiologies have to be excluded Two different types of DCM have been found upon histological examination.

VTEC, smittskydd på gårdsnivå

Verotoxinproducerande E. coli är en vatten- och livsmedelsburen patogen med nötkreatur som reservoar. Bakterien ger hos människa upphov till en enterohemorragisk sjukdom, i vissa fall med HUS, hemolytiskt uremiskt syndrom, som följd. HUS är mycket allvarligt och den största anledningen till att barn drabbas av akut njursvikt. Bakterien smittar fekal-oralt och boskap och människor som blivit infekterade kan utskilja mycket stora mängder bakterier i sin avföring.

Antibiotic resistance associated with bacteria in irrigation water : a case study of irrigation ponds in Southern Sweden

The focus of this project was to characterize the occurrence of ESBL-­?producing bacteria in two irrigation water ponds in Southern Sweden. Samples were taken from two ponds nearby each other, from which analyses were made based on levels of community and individual isolates. Community samples were used for attempts for characterization of resistance patterns in irrigation water using the Omnilog PM-­?plate system. The growth of community microbiota in the presence of the following antibiotic substances was assessed; amikacin, gentamicin, kanamycin, penicillin G, ampicillin, piperacillin, trimethoprim, potassium tellurite and ciprofloxacin. Isolates were pure cultured using semi-­?selective media: LB, Rainbow Agar, mEnterococcus, 0.1 TSA and VRBD. A total of 177 isolates were isolated randomly. Each isolate was identified using the Omnilog GENIII-­?system of biochemical characterization. Further, the isolates were tested on Brilliance ESBL-­?agar for their ability to grow. Out of the total number of isolates, 30 were selected, preferably Enterobacteriaceae or Pseudomonas spp., based on their high similarity to library strain during the identification in the Omnilog-­?system. These were further characterized using Etest-­?sticks. Three selected strains were picked for further analyses using exogenous isolation for attempts to simulate horizontal gene transfer, and Omnilog PM-­?panels containing various antibiotics of interest. Selections of samples were chosen for molecular tests targeting plasmid-­?borne resistance genes CTX-­?M1, CTX-­?M2 and SHV. The method for assessing community-­?resistance patterns showed ambiguous data that was difficult to interpret; further optimization is recommended. For all tested PM-­?plates, generally greatest differences between substances were found among wells with the strongest concentration of antibiotic substance. A total of 175 isolates displayed ability to grow on ESBL-­?agar. Etests confirmed ability of isolates to resist many ?-­?lactam antibiotics and many were clinically resistant to certain substances. No plasmids were transferred during exogenous isolation. During molecular tests, a few matches were found for the CTX-­?M1 gene. Isolates analyzed with Omnilog PM-­?plates showed resistance to most compounds tested. The isolates showed greatest resistance toward penicillin G, ampicillin, amikacin, kanamycin and trimethoprim. In the study, it was established that resistance among bacteria was frequently occurring in the irrigation water, and ?-­?lactamase producing bacteria was very common. Extended studies are needed to assess the frequency-­? and occurrence of horizontal gene transfer (HGF) in this environment. Although some potential corresponding data is found, it is at this point not possible to determine whether the resistances are due to antibiotics used in veterinary medicine, human medicine or one additional reason is travel and trade. in irrigation water using the Omnilog PM-­?plate system. The growth of community microbiota in the presence of the following antibiotic substances was assessed; amikacin, gentamicin, kanamycin, penicillin G, ampicillin, piperacillin, trimethoprim, potassium tellurite and ciprofloxacin. Isolates were pure cultured using semi-­?selective media: LB, Rainbow Agar, mEnterococcus, 0.1 TSA and VRBD. A total of 177 isolates were isolated randomly. Each isolate was identified using the Omnilog GENIII-­?system of biochemical characterization. Further, the isolates were tested on Brilliance ESBL-­?agar for their ability to grow. Out of the total number of isolates, 30 were selected, preferably Enterobacteriaceae or Pseudomonas spp., based on their high similarity to library strain during the identification in the Omnilog-­?system. These were further characterized using Etest-­?sticks. Three selected strains were picked for further analyses using exogenous isolation for attempts to simulate horizontal gene transfer, and Omnilog PM-­?panels containing various antibiotics of interest. Selections of samples were chosen for molecular tests targeting plasmid-­?borne resistance genes CTX-­?M1, CTX-­?M2 and SHV. The method for assessing community-­?resistance patterns showed ambiguous data that was difficult to interpret; further optimization is recommended. For all tested PM-­?plates, generally greatest differences between substances were found among wells with the strongest concentration of antibiotic substance. A total of 175 isolates displayed ability to grow on ESBL-­?agar. Etests confirmed ability of isolates to resist many ?-­?lactam antibiotics and many were clinically resistant to certain substances. No plasmids were transferred during exogenous isolation. During molecular tests, a few matches were found for the CTX-­?M1 gene. Isolates analyzed with Omnilog PM-­?plates showed resistance to most compounds tested. The isolates showed greatest resistance toward penicillin G, ampicillin, amikacin, kanamycin and trimethoprim. In the study, it was established that resistance among bacteria was frequently occurring in the irrigation water, and ?-­?lactamase producing bacteria was very common. Extended studies are needed to assess the frequency-­? and occurrence of horizontal gene transfer (HGF) in this environment. Although some potential corresponding data is found, it is at this point not possible to determine whether the resistances are due to antibiotics used in veterinary medicine, human medicine or one additional reason is travel and trade..

Årstidsdynamik för kvicksilver i ett sövattensediment :

The limit for mercury in fish, set by health authorities, is exceeded in about half of the lakes in Sweden. Methyl mercury (MeHg) is the most toxic form of mercury and accumulates in fish. Therefore transformation of inorganic mercury (Hg) to methylmercury (MeHg) is an important process that we need to understand in order to possibly counteract the negative effects of mercury in the environment. The seasonal dynamics of mercury biogeochemistry is likely of great importance for the accumulation of MeHg in the aquatic food web. In thesis the chemical speciation and transformations of Hg and MeHg in bottom waters and sediments is followed in Ängessjön, a small lake located on the east coast in the middle of Sweden. The lake is not directly affected by any industrial pollution and concentrations of Hg in the sediment reflect the atmospheric deposition in this area, as well as processes taking place along the hydrological pathways from soil to lake. Samples from sediment, bottom- and streamwater were collected in average every second month during the period Feb.

Iron bioavailability and pro- and prebiotics

Iron deficiency is one of the most frequent micronutrient deficiencies around the world. Low iron bioavailability simultaneously with a high iron requirement is a high risk factor for developing iron deficiency. Probiotics are microorganisms that confer a health benefit on the host. Prebiotics are oligosaccharides which provide a health benefit on the host due to a positive modulation of the microflora in the gut. The aim of this paper is to evaluate if there is a connection between pro-and/or prebiotics and iron bioavailability.

Kartläggning av stallbyggnader och djurhållningssystem inom mjölkproduktion ur salmonellasynpunkt

Promoters are genetic elements that facilitate the transcription of a gene and they have been found in front of non-coding RNA (ncRNA) genes in different organ-isms, e.g. the model plant Arabidopsis thaliana. A similar element, DUSE, has been found in front of ncRNAs in the social amoeba Dictyostelium discoideum and a part of this project has been to analyze the function of this putative promoter element through cloning and expression studies. A construct to analyze the func-tion of DUSE was successfully designed and introduced into D. discoideum but full expression studies were not finished because of shortage of time.

KRAV-grisar har fler ledanmärkningar än konventionellt uppfödda grisar.

Promoters are genetic elements that facilitate the transcription of a gene and they have been found in front of non-coding RNA (ncRNA) genes in different organ-isms, e.g. the model plant Arabidopsis thaliana. A similar element, DUSE, has been found in front of ncRNAs in the social amoeba Dictyostelium discoideum and a part of this project has been to analyze the function of this putative promoter element through cloning and expression studies. A construct to analyze the func-tion of DUSE was successfully designed and introduced into D. discoideum but full expression studies were not finished because of shortage of time.

Undersökning av förekomst av okända virus hos svenska fjällrävar med encefalit :

The artic fox is under threat of extermination in Europe. The population decreased strongly at the beginning of the twentieth century because of intensive hunting. The artic fox was placed under protection by law 1928 in Sweden but despite this the population has had difficultly to recover. This can depend on several reasons, but the main threats are shortage of food and competition from the red fox. Along with Norway and Finland, Sweden has carried out a project called SEFALO (Saving the Endangered Fennoscandian Alopex lagopus), whose objectives were to prevent continued decreased populationnumbers and through, for example supplementary feeding, help the population to recover.

<- Föregående sida 13 Nästa sida ->