A new rapid computer assisted micro-titer plate interferon assay system was developed and characterized for use in high capacity clinical and research applications. The biological aspect of the assay was a modification of the assay methods of Finter, Armstrong and McManus. It was an application of spectrophotometric quantification of the reduction of viral cytopathic effect (CPE) as reflected by neutral red dye uptake by viable cells. A computer program was developed for the extrapolation of raw data to reference interferon units.

Orientador: Jean-Paul Laclau / Resumo: As mudanças climáticas têm causado alterações na temperatura e também nos regimes de precipitação do planeta, aumentando a probabilidade de ocorrência de secas mais severas, o que, no cenário florestal, pode resultar na mortalidade de florestas ao redor do mundo. Assim, é necessário um conhecimento mais detalhado sobre a dinâmica de absorção de água e nitratos pelas raízes das árvores, que explique o comportamento das árvores sob extrema seca. O objetivo do estudo foi avaliar a distância máxima do tronco e a profundidade máxima de absorção de nutrientes e água pelas raízes das árvores em florestas crescendo sobre Neossolos Quartzarênicos muito profundos, utilizando o 15N como marcador. As consequências do status social das árvores, comparando árvores dominantes e dominadas do mesmo genótipo numa floresta monoclonal foram estudadas em plantios de um clone híbrido de Eucalyptus urophylla x Eucalyptus grandis durante a estação seca. Os efeitos da sazonalidade (comparando as estações seca e chuvosa) foram estudados em três espécies do Cerrado: i) Xylopia aromatica (Lam.) Mart.; ii) Coussarea hydrangeifolia (Benth.) Müll.Arg.; and iii) Miconia albicans (Sw.) Steud. Além disso, foi avaliada a existência de uma complementaridade de nicho no solo entre essas espécies do Cerrado, com uma absorção do marcador em camadas diferentes. O marcador NO3--15N foi aplicado em talhões de eucalipto com 7 meses, 1,2 anos, 2,2 anos e 6,4 anos de idade, a várias profundidades do solo em 60 pontos, s... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor

Escherichia coli is an incredibly diverse group of bacteria that consist of both commensal and pathogenic strains that cause disease in a wide variety of tissues in many different animals. The current dogma, based on years of extensive molecular and genetic studies, is that individual strains have adapted to specific environments through acquisition of specific genes or come from lineages that are particularly suited to a unique tissue or host. However, mastitis-associated E. coli (MAEC) have thus far resisted such descriptions. The fitness and virulence factors of MAEC are poorly understood and molecular tools are rarely applied. This dissertation reports new approaches to assess virulence of MAEC strains, enabling comparative genomic studies across multiple strains as well as genome-wide analysis of specific successful MAEC isolates. I outline the identification of the first virulence factor of MAEC, a ferric dicitrate receptor that is essential for colonization of a lactating mammary gland in a murine model. Genes previously studied in the contexts of other extraintestinal E. coli infections were also implicated in mastitis. These include a type III capsule found in the MAEC strain M12, which is crucial for dissemination from the mammary gland to the spleen. A mutant unable to produce capsule had diminished lethality in Galleria mellonella and decreased kidney colonization in a mouse urinary tract infection. I also report a link between zinc uptake, bile salts, and capsule production. I have utilized a transposon mutant library paired with deep sequencing of transposon junctions to elucidate the fitness factors needed to grow in milk and colonization of both murine and insect models. This analysis implicates a broad set of genes and metabolic pathways pertinent to these conditions. In addition to Tn-seq, I sequenced 94 MAEC genomes and identified genes associated with disease severity, growth in milk, and colonization of mammary glands in cow and mouse models. Employing bioinformatic tools to interrogate the pan-genome, I identified genes that are involved in biofilm formation and adhesion that were specifically associated with either mild or severe disease. In summary, I have employed several powerful genetic, genomic, computational, and molecular approaches to the characterization of mastitis associated E. coli. This work provides the groundwork for future experiments to better understand the host-pathogen interface and a model for mastitis-associated E. coli.

No description available.

Bakgrund: HPV är den vanligaste sexuellt överförbara infektionen i Sverige. Flickor vaccineras redan mot HPV, från hösten 2020 kommer pojkar vaccineras. Vaccinationstäckningen är lägre än övriga vaccin i vaccinationsprogrammet. Information och rekommendation från vårdgivare har visat sig ha betydelse för vaccinationstäckningen. Syftet: Studiens syfte var att beskriva skolsköterskors syn på sin roll som vaccinationsförespråkare vid införandet av HPV-vaccination till pojkar i det allmänna vaccinationsprogrammet för barn. Metod: Kvalitativ metod användes i studien. Semistrukturerade intervjuer med åtta skolsköterskor verksamma i Stockholmsområdet genomfördes. Resultatet analyserades med kvalitativ innehållsanalys. Resultat: Analysen resulterade i fyra kategorier; Betydelsen av att ge information, Utmaningar med att vara vaccinationsförespråkare, Betydelsen av egen kunskap, Ansvar som vaccinationsförespråkare. Ur resultatet framträdde temat Ett livräddande engagemang. Konklusion: HPV-infektioner spelar en stor roll för uppkomsten av cancer och orsakar många dödsfall varje år. Skolsköterskors arbete för att uppnå en hög vaccinationstäckning har därför stor betydelse och kan i förlängningen ses som en insats som förhindrar lidande och räddar liv. För att uppnå hög vaccinationstäckning måste skolsköterskor ha goda kunskaper för att ge aktuell och adekvat information till elever och vårdnadshavare. Vaccinets sexuella koppling, relationen till vårdnadshavare och samhällets syn på vaccinet ses av skolsköterskorna som utmaningar för nå en hög vaccinationstäckning. / Background: Human papillomavirus (HPV) is the most common sexually transmitted disease in Sweden. Girls are already vaccinated against HPV and from the autumn of 2020 boys will be initiated. The vaccine uptake is lower compared to other vaccines in the national vaccination program. Information and recommendation from healthcare providers has been proven to be important for vaccine uptake. Aim: The aim of the study was to describe school nurses view on their role as opinion leaders during introduction of HPV-vaccine to boys in the national vaccination program for children. Method: A qualitative methodology was used in the study. Semi-structured interviews with eight school nurses active around Stockholm were accomplished. The results were analyzed by content analysis. Results: The analysis resulted in four categories; The importance of giving information, Challenges being an opinion leader, The importance of individual up to date knowledge and Responsibility as an opinion leader. From the result a theme appeared A lifesaving commitment. Conclusion: HPV-infections plays an important role for the appearance of cancer and causes many deaths each year. School nurses’ assignment to achieve high vaccination uptake has a major importance and may in long term prevent suffering and save life. To achieve high vaccine uptake school nurses need knowledge to be able to give current and adequate information to students and parents. The sexual connection, the relationship to parents and society’s view on the vaccine are seen as challenges to achieve a high vaccine uptake by the school nurses.

No description available.

Useful properties render titanium dioxide nanomaterials (NMs) to be one of the most commonly used NMs worldwide. TiO2 powder is used as food additives (E171), which may contain up to 36% nanoparticles. Consequently, humans could be exposed to comparatively high amounts of NMs that may induce adverse effects of chronic exposure conditions. Visualization and quantification of cellular NM uptake as well as their interactions with biomolecules within cells are key issues regarding risk assessment. Advanced quantitative imaging tools for NM detection within biological environments are therefore required. A combination of the label-free spatially resolved dosimetric tools, microresolved particle induced X-ray emission and Rutherford backscattering, together with high resolution imaging techniques, such as time-of-flight secondary ion mass spectrometry and transmission electron microscopy, are applied to visualize the cellular translocation pattern of TiO2 NMs and to quantify the NM-load, cellular major, and trace elements in differentiated Caco-2 cells as a function of their surface properties at the single cell level. Internalized NMs are not only able to impair the cellular homeostasis by themselves, but also to induce an intracellular redistribution of metabolically relevant elements such as phosphorus, sulfur, iron, and copper.

The measurement of fluorine penetration into archeological flint artifacts using Nuclear Reaction Analysis (NRA) has been reported to be a potential dating method. However, the mechanism of how fluorine is incorporated into the flint surface, and finally transported into the bulk is not well understood. This research focuses on the study of the fluorine uptake phenomenon of flint mineral in aqueous fluoride solutions. Both theoretical and experimental approaches have been carried out. In a theoretical approach, a pipe-diffusion model was used to simulate the complicated fluorine transportation problem in flint, in which several diffusion mechanisms may be involved.

his study compared auditory behavioral and physiological measures among three subject groups: 1) Normal control subjects, 2) subjects who were on a prescribed SSRI for depression, and 3) subjects who were prescribed an SSRI for depression, but were not medicated at the time of testing. Test measures included: Standard audiological tests (audiometry and tympanometry), electrophysiological procedures for analysis of auditory- evoked brainstem and late responses, and standardized behavioral speech tests (SCAN-A, SSI, and the low predictability sentence list of the R-SPIN). Analysis of results indicated a statistically significant increase of group mean amplitude of the ABR peak V, from 15dBnSL to 55dBnSL, in the non-medicated group compared to controls. Also, the non-medicated group scored significantly less favorably than controls on the most challenging listening condition (-20 MCR) of the SSI, in the left ear. Although other test measures indicated consistent differences between these two groups, they were not, however, significant.

The purpose of this study was to investigate the relationship between selective serotonin reuptake inhibitor (SSRI) medication on auditory skills in clinically depressed subjects. Experimental subjects prescribed an SSRI were tested in a medicated and an unmedicated condition, and the test results were compared. Furthermore, the experimental group was compared with a control group consisting of normal subjects. Test measures included pure tone audiometry, tympanometry, acoustic reflex thresholds, and auditory electrophysiologic measures such as auditory brainstem and auditory late responses. An assessment scale for depression (Beck Depression Inventory-II) was also used. Results indicated statistically significant differences for the BDI-II between the control and experimental groups for both conditions. Electrophysiologic measures indicated a significantly shorter latency for auditory late potential P1 at 55 dBnSL, and a significantly larger amplitude at 45 dBnSL for the N1/P2 component for the unmedicated group. Although the other measures showed trends, they did not reach significance.