<p>Diss. (sammanfattning) Umeå : Umeå universitet, 1996, härtill 4 uppsatser</p> / digitalisering@umu

Woodchucks are the preferred animal model to study chronic viral hepatitis and the development of hepatocellular carcinoma (HCC), which occurs as a result of infection with woodchuck hepatitis virus. Significant elevations in the phosphomonoester peak in 31P-MRS spectrum correlated to the presence of HCC. Ex vivo 31P-NMR determined that HCC tissue had significantly elevated concentrations of PC compared to uninfected control tissues, confirming that PME is specific to the tumour’s growth. Finally, a recombinant vaccinia virus was constructed to stimulate the immune systems of infected woodchucks against cells expressing core antigens. Despite reductions in surface antigen expression and viral load, elevations in serum GGT and the PME in 31P-MRS indicated that there was tumour growth in treated woodchucks. In conclusion, the PME peak represents a potential biomarker of cancerous growth when used in conjunction with serological tests to detect HCC in the liver due to chronic hepatitis virus infection.

Woodchucks are the preferred animal model to study chronic viral hepatitis and the development of hepatocellular carcinoma (HCC), which occurs as a result of infection with woodchuck hepatitis virus. Significant elevations in the phosphomonoester peak in 31P-MRS spectrum correlated to the presence of HCC. Ex vivo 31P-NMR determined that HCC tissue had significantly elevated concentrations of PC compared to uninfected control tissues, confirming that PME is specific to the tumour’s growth. Finally, a recombinant vaccinia virus was constructed to stimulate the immune systems of infected woodchucks against cells expressing core antigens. Despite reductions in surface antigen expression and viral load, elevations in serum GGT and the PME in 31P-MRS indicated that there was tumour growth in treated woodchucks. In conclusion, the PME peak represents a potential biomarker of cancerous growth when used in conjunction with serological tests to detect HCC in the liver due to chronic hepatitis virus infection.

Submitted by Nathália Faria da Silva (nathaliafsilva.ufv@gmail.com) on 2017-06-23T19:03:26Z No. of bitstreams: 1 texto completo.pdf: 790178 bytes, checksum: f15ebd918e983ee92d3e70cf19f11647 (MD5) / Made available in DSpace on 2017-06-23T19:03:26Z (GMT). No. of bitstreams: 1 texto completo.pdf: 790178 bytes, checksum: f15ebd918e983ee92d3e70cf19f11647 (MD5) Previous issue date: 2004-11-26 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Com a elevação dos custos da adubação mineral, resíduos orgânicos produzidos pelo meio rural passaram a ser mais usados para melhorar as condições químicas e físicas dos solos. Porém, não se sabe ao certo quais as doses mais adequadas de cada tipo de resíduo orgânico para diferentes culturas nos diferentes ambientes edáficos e também pouco se sabe dos possíveis riscos ambientais decorrentes de seu uso. Desta maneira, visou-se avaliar o potencial fertilizante de camas de aviário quanto a P, dado ser este o nutriente mais limitante nos solos brasileiros. Assim, foram objetivos deste trabalho: obter uma estimativa das doses adequadas de camas de aviário para maximizar a produção de matéria seca de plantas de milho e avaliar a participação de formas orgânicas e inorgânicas de P destas camas de aviário e sua dinâmica de transformação, na ausência e na presença de solo. No experimento 1, foram avaliados cinco tipos de camas de aviário em doses correspondentes a 0, 20, 40, 80 e 160 t ha -1 , que foram aplicadas em dois Latossolos (um muito argiloso e o outro de textura média) em três repetições, incubados por 15 dias e realizados três cultivos sucessivos de milho, determinando-se a matéria seca produzida e o P acumulado na planta. No experimento xiv2, determinaram-se os teores de formas orgânicas de P (Po) e inorgânicas (Pi) de cinco camas de aviário em três repetições e as transformações que ocorreram nessas formas após incubação na ausência ou presença de solo, utilizando-se fracionamento químico e ressonância magnética nuclear de 31 P ( 31 P-RMN). O experimento 3 foi conduzido semelhantemente ao 1, porém com dose única de cama de maravalha de 80 t ha -1 , além de um tratamento-testemunha (ausência de aplicação de cama) visando avaliar a dinâmica das transformações das formas de P no solo com o tempo, por meio de fracionamento químico. Os resultados indicaram que para se obter a produção máxima acumulada em três cultivos, sem que ocorressem efeitos tóxicos às plantas, seria adequada a aplicação de uma dose de cama de aviário equivalente a 70 t ha -1 para o solo muito argiloso e em torno de 60 t ha -1 para o solo textura média. Verificou-se que os ortofosfatos de monoésteres foram as formas de Po predominantes nas camas de aviário (15,1 % do P extraído por água), porém, os ortofosfatos de diésteres estávam presentes em quantidades apreciáveis (4,7 % do P extraído por água) e disponibilizaram Pi mais rapidamente. A mineralização do Po foi relativamente rápida nos primeiros 15 dias, mas existiu diferença significativa nas taxas de transformação de Po em Pi entre tipos de camas. No solo, a cama de casca de café teve maior taxa de mineralização de Po (44,7 %), enquanto a menor taxa foi observada para a cama de maravalha (4,9 %). As maiores transformações do P nas diversas frações ocorreram durante o período de incubação (0 a 15 dias), sendo que no solo argiloso as frações de P de baixa disponibilidade (extraídas por hidróxido e residual) predominaram, mas no solo de textura média as formas mais lábeis de P (por resina e por bicarbonato) e o P extraído por água apresentaram maiores teores. O solo de textura média, comparativamente ao muito argiloso, poderia estar mais sujeito à perda de P solúvel em água por lixiviação quando fertilizado com camas de aviário. / Due to the rising costs of chemical fertilization, organic compounds produced in rural areas are being more frequently used to improve chemical and physical soil conditions. However, it is not well known the adequate doses of different types of organic residues for distinct crops and soils. Furthermore, little is known on the possible risks that the use of these organic residues may pose to the environment. This study sought to evaluate the potential of different poultry litters to supply phosphorus (P), the nutrient most limiting to crop growth in Brazilian soils. Thus, the objectives of this research were: to obtain an estimate of adequate doses of poultry litter to maximize growth of corn plants and evaluate the organic and inorganic P forms in the poultry litter and the dynamics of their transformation, in the absence and presence of soil. In experiment 1 it was evaluated five types of poultry litter in doses equivalent to 0, 20, 40, 80 and 160 t ha -1 , applied to two Oxisols (a clayey and a sandy-loam), with three replicates. The soils plus poultry litters mixtures were incubated for 15 days under greenhouse conditions and then corn was cultivated for three successive times. When plants were 25-day old they were harvested and the dry matter production and P uptake were determined. In experiment 2, it was determined the contents of organic (Po) and xviinorganic (Pi) phoshorus forms of the poultry litters and the transformations of these P forms after their incubation in the absence and presence of soil, using wet chemical fractionation and 31 P – Nuclear Magnetic Ressonance Spectroscopy ( 31 P-NMR). Experiment 3 was carried out similarly to experiment 1, except that only wood chip litter was used (0 and 80 t ha -1 ) with the objective of evaluate the transformations of P forms in the soil along the time of incubation using wet chemical fractionation. The results indicate that in order to obtain the maximum estimated growth (accumulated in the three cultivations) and no toxicity effect occurred to plants, a dose of poultry litter equivalent to 70 t ha -1 in the clayey soil and 60 t ha -1 in the sandy-loam soil would be adequate. It was found that monoester orthophosphates were the dominant Po forms in the poultry litter (15.1% of P extracted with water) but, the diester orthophosphate were present in substantial amount (4.7 % of P extracted with water) and mineralized more rapidly. The mineralization of Po was relatively rapid in the first 15 days, but there were significant differences in the Po and Pi transformation rates among poultry litter types. In the soil, the coffee cherry skin litter showed the greatest mineralization rate (44.7%), whereas the lowest rate was observed for the wood chip litter (4.9%). The majority of transformations of P from several forms occurred during the incubation period (0 to 15 days). In the clayey soil the low availability P fractions (residual and NaOH-extracted) were dominant, but in the sandy-loam soil more labile P fractions (resin and bicarbonate-extracted) and water-extractable P presented higher values. Compared to the clayey soil, the sandy-loam would probably be more prone to soluble P losses in the percolation water when fertilized with poultry litter.

In tundra, phosphorus (P) is an important macronutrient for plants and microorganisms. A major fraction of P exists as organic compounds in the topsoil which can be mineralized to bioavailable inorganic P. Since mineralization is positively related to temperature, climate warming is likely to increase P bioavailability but the extend of these changes may also depend on vegetation cover and soil properties. I assessed organic and inorganic P concentrations across an elevation and vegetation gradient in northern Sweden using one dimensional (1D) solution 31P nuclear magnetic resonance spectroscopy. I hypothesized that concentration of labile soil P will decrease with increasing elevation (decreasing temperature) and that soils with meadow vegetation will contain higher concentrations of labile P than heath soils. Concentration of labile P in the form of Resin-P and polyphosphates decreased with elevation whereas less labile orthophosphate monoesters increased. Across vegetation types, polyphosphates were more abundant in heath and meadow contained higher concentrations of monoesters. The inverse response of Resin-P and monoesters to elevation may be best explained by lowered organic P mineralization in colder climate. High concentrations of polyphosphates at the lowest elevation may indicate an increased presence of fungal communities associated with mountain birch forest. Heath seemed to be more dominated by fungal communities than meadow and higher concentration of monoesters in meadow indicated a higher soil sorption capacity. In a broader view, the results may suggest that a warmer climate increases mineralization of organic P in form of orthophosphate monoesters to more labile P forms. This effect might be enhanced by an upward movement of the tree line and might be more pronounced in heath than meadow soils due to a higher fungal activity.

Lignin är en restprodukt från massaindustrin som har stor potential för vidareanvändning i bland annat materialutveckling. För att utreda möjliga användningsområden för ett specifikt lignin är det viktigt att ha kunskap om ligninets molekylstruktur och bindningar. 31P-NMR spektroskopi kan användas som analysmetod för kvantifiering av hydroxylgrupperna hos lignin. Vid användning av 31P-NMR spektroskopi måste ligninprovet först derivatiseras med ett derivatiserings-reagens innehållande fosfor. Till analyserna behövs en lämplig intern standard för att kunna beräkna halten av de olika strukturelementen i lignin. RISE Research Institutes of Sweden ville se om det gick att komplettera analyserna av lignins struktur med hjälp av ett nytt derivatiserings-reagens, DR(I) (2-chloro-1,3,2-dioxaphospholane). Tidigare har derivatiserings-reagenset DR(II) (2-chloro-4,4,5,5-tetramethyl-1,3,2-dioxaphospholane) använts. Det nya derivatiserings-reagenset DR(I) har en liknande struktur men är en mindre molekyl och förväntades därför kunna analysera fler strukturelement som tidigare inte kunnat påvisas. Projektet har undersökt 10 olika interna standarder med DR(I) i syfte att hitta den bästa interna standarden. Den första som undersöktes är den som används med DR(II), N-hydroxy-5-norbornene-2,3-dicarboxylic acid imine. Av de undersökta interna standarderna är tre tagna från tidigare litteratur och sex är tidigare helt obeprövade. Samtliga undersöktes både som blankprov och med ett utvalt barrveds-kraftlignin. N-hydroxy-1,8-naftalimid (intern standard 4) var bäst baslinjeupplöst men inte tillräckligt stabil för att kunna användas som intern standard. Bisfenol-A (intern standard 3) var den interna standard som var den mest stabila och alla stabilitetstest utfördes med denna interna standard som referens. Av de tidigare obeprövade interna standarderna är det endast N-hydroxysuccinimide (intern standard 5) som kan användas som intern standard, dock är den inte tillräckligt stabil. N-hydroxy-5-norborene-2,3-dicarboxylic acid imine (intern standard 1) ansågs vara den bäst lämpade interna standarden. Denna prövades med olika typer av kraftlignin; barrveds-kraftlignin, lövveds-kraftlignin samt ett blandlignin. Den undersöktes även med ”milled wood lignin”. För detta lignin var det uppenbart att den valda interna standarden inte var helt optimal. En annan intern standard med bättre baslinjeupplösning skulle vara ett bättre alternativ för ”milled wood lignin”. Relaxationstiden mättes även för intern standard 1 och de olika strukturerna i ligninet. RISE Research Institutes of Sweden kan använda DR(I) som komplement till den nuvarande analysen med DR(II) vid beräkning av mängden av de sekundära alifatiska grupperna. En uppdelning av de olika formerna (erythro och threo) av den vanligaste bindningen hos lignin, β-O-4-bindningen, går också att urskilja. Eftersom denna bindning bryts i sulfatmassaprocessen är signalen svag, vilket gör att en uppdelning av erythro och threo vid beräkningarna av hydroxylgrupperna inte är relevant. / Lignin is a residue from the pulp industry, which has great potential for further use, including material development. To investigate possible uses for a specific lignin, it is important to have knowledge of the lignin's molecular structure. 31P NMR spectroscopy can be used when quantifying the hydroxyl groups of lignin. When using 31P NMR spectroscopy, the lignin sample must be derivatized with a phosphorous reagent. The analysis requires an appropriate internal standard to calculate the amount of the different structural elements in lignin. RISE Research Institutes of Sweden wishes to complement the analyzes of lignin structures using a new derivatization reagent, DR(I) (2-chloro-1,3,2-dioxaphospholane). Previously, the derivatization reagent DR(II) (2-chloro-4,4,5,5-tetramethyl-1,3,2-dioxaphospholane) has been used. The new derivatization reagent DR(I) has a similar structure but is a smaller molecule. In this report, 10 different internal standards have been examined with DR(I) to find the most suitable one. The first internal standard, N-hydroxy-5-norbornene-2,3-dicarboxylic acid imine, was used with DR(II). Three internal standards were from articles and six were previously unexamined. All of these were first tested as blanks without lignin and then with a selected softwood lignin. N-hydroxy-1,8-naphthalimide (internal standard 4) showed the best resolution but was not stable enough to be used as an internal standard. Bisphenol A (internal standard 3) was the most stable derivatized internal standard and the stability tests were performed with this internal standard as a reference. Of the previously unexamined internal standards, N-hydroxysuccinimide (internal standard 5) was the only appropriate internal standard to use. However, it was not as stable as N-hydroxy-5-norbornene-2,3-dicarboxylic acid imine (internal standard 1), which was found to be the most suitable internal standard. N-hydroxy-5-norbornene-2,3-dicarboxylic acid imine (internal standard 1) was examined with different types of kraft lignin; softwood kraft lignin, hardwood kraft lignin and a mixture kraft lignin. N-hydroxy-5-norbornene-2,3-dicarboxylic acid imine was also investigated with "milled wood lignin". For ”milled wood lignin” it became obvious that the resolution of the selected internal standard can be improved. Another internal standard that has not been examined in this report could be a better option. The relaxation time was also determined for N-hydroxy-5-norbornene-2,3-dicarboxylic acid imine and the different hydroxyl groups of lignin. RISE Research Institutes of Sweden can use DR(I) in analysis of kraft lignin as a complement to the currently used method with DR(II) for calculating the amount of secondary aliphatic groups. A differentiation of erythro and threo of the most common binding (β-O-4) can also be noted with these lignins with DR(I). Since this bond is broken to a large extent in the kraft process, the signal is week. This means that when calculating the hydroxyl groups, a separation of erythro and threo is not relevant.

In this work 23Na MAS NMR was validated as a successful quantitative method for studies of exchanging sodium in bentonites useful, in particular, for studies of ion-exchange kinetics. Na-enriched bentonites equilibrated in a re-circulated process water at iron-oxide pelletizing plants may acquire properties of Ca-bentonites after already 20 minutes of the equilibration time, since &gt;50 % of sodium ions will be exchanged by calcium ions during first minutes of bentonite placed in contact with the process water. It was shown that all sodium activated bentonites used in this study exchange &gt;50% of sodium in Na+/Ca2+ and ca 20 % of sodium in binary Na+/Mg2+ systems with the same bentonite/solution ratio and same concentrations of these ions in aqueous solutions as in the process water at a pelletizing plant. In total, approximately 50 % of the exchangeable sodium in original bentonites was exchanged after equilibrating of bentonites in the process water already after 20 minutes. Experimental Na+/Ca2+ exchange curves for ‘model’ Ca2+(aq) solutions and for process water are very similar as Ca2+ is the dominant constituent in the process water. Since bivalent ions (Ca2+ and Mg2+) that present in the process water readily replace Na+ ions, Na-bentonite transforms into Ca- or Mg- bentonite, which have worse rheological, swelling and, therefore, binding properties. This ion-exchange process can influence the binder performance in the pelletizing process. Taking into account that fluorapatite is one of the components present in a blend of minerals processed, possible interactions between orthophosphate (the principal anionic component of apatites) and bentonites in aqueous suspensions are considered. It was found that sorption of orthophosphate on Ca-montmorillonite follows a different pattern from sorption of orthophosphate on aluminum oxides and kaolinite. While there is a small amount of sorption below pH 7, which may involve inner-sphere complexation and precipitation of AlPO4 to Al-OH edge sites on the montmorillonite crystals, most sorption of orthophosphate occurs at higher pH. Both macroscopic sorption measurements and solid-state 31P MAS NMR suggest that above pH 7 there is precipitation of proton depleted calcium phosphate phases. Based on both 31P chemical shifts and 31P chemical shift anisotropies it was concluded that the principal precipitated phased are most likely ‘brushite-like’ phases. Very short spin-lattice T2(31P) relaxation times (≤100 μs) for the orthophosphate/bentonite systems can possibly be explained by the presence of paramagnetic Fe in bentonites. Since there are insufficient concentrations of soluble Fe species in the supernatant solution that may give rise to the observed effects, it is likely that orthophosphate is precipitated as thin layers on the surfaces of montmorillonite crystals, where phosphorus may interact with Fe atoms present in the crystal lattice. PO4-tetrahedra in sorbed species can be also distorted giving rise to a larger 31P CSA than for pure ‘apatite-like phases’. 29Si MAS and 1H-29Si CP/MAS NMR experiments on bentonite samples also performed in this work provide information about impurities of quartz in bentonites, a level of substitution of aluminum by iron atoms in the structure of montmorillonite and about the degree of hydration of montmorillonite. 29Si NMR experiments on bentonite incubated with waterglass in aqueous suspensions at concentrations of sodium silicates as in the process water demonstrated that one can follow the process of polymerization of waterglass in solutions and also detect sodium silicates polymerized on surfaces of bentonites already after 1 hour of incubation. Polymerized waterglass sorbed on bentonite surfaces may also alter rheological, swelling and, therefore, binding properties of sodium-activated bentonites used in pelletization of iron-oxide ores.

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INTRODUCTION: The detection of a second inorganic phosphate (Pi) resonance, a possible marker of mitochondrial content in vivo, using phosphorus magnetic resonance spectroscopy (31P- MRS) at 3T is technically challenging, which may prevent its reproducible quantification. PURPOSE: To determine the reproducibility of resting alkaline inorganic phosphate (Pialk) measurement using 31P-MRS in human skeletal muscle at 3 tesla (T). METHODS: Resting 31P- MRS of the quadriceps muscles was acquired on two separate visits, within seven days, in 13 healthy, sedentary to moderately active young adults using a whole-body 3T MR system. Measurement variability related to coil position, shimming procedure, and spectral analysis were also quantified. 31P-MRS data were acquired with a 31P/1H dual-tuned surface coil positioned on the quadriceps using a pulse-acquire sequence. Test-retest absolute and relative reproducibility were analyzed using coefficient of variation (CV) and intra-class correlation coefficients (ICC), respectively. RESULTS: Pialk demonstrated a within-subject reproducibility marginally greater then the 10% cutoff (CV: 10.6 ± 5.4%; ICC: 0.80), but still appropriate given its small concentration in relation to other 31P metabolites. Proximo-distal change in coil positioning along the length of the quadriceps induced large variability in Pialk quantification (CV: 21.1%). In contrast, measurement variability due to repeated shims on consecutive scans from the same muscle sample (CV: 6.6%), and the automated spectral processing procedure, were minor (CV: 2.3%). Both metrics of absolute and relative reproducibility of Pialk were of similar magnitude to other well-resolved metabolites (e.g., phosphocreatine, Pi, and phosphodiester). CONCLUSION: Using multiple metrics, the present study established the high reproducibility of Pialk quantification by 31P-MRS using a surface coil on the quadriceps muscle at 3T. However, large variability in Pialk quantification can originate from positioning the coil on the most distal part of the quadriceps, which should be avoided due to shimming inhomogeneity.