The nuclear factor-kB (NF-kB) signaling cascade is comprised of two branches, the canonical and alternative NF-kB pathways. Signaling through the alternative NF-kB pathway culminates in the activation of the downstream transcription factor subunits, RELB and NF-kB2. The biological roles of RELB and NF-kB2 within the B cell lineage have been obscured in constitutional knockout mice by the diverse functions of these subunits in non-B cell types. To overcome these limitations, conditional alleles were generated to investigate the roles of RELB and NF-kB2 in B cell development. These alleles allowed the identification of complex functional requirements for RELB and/or NF-kB2 in naïve B cells, germinal center (GC) B cells and plasma cells (PCs). These functional requirements may have implications for B cell malignancies that display mutations that constitutively activate the alternative NF-kB pathway. A large body of work has demonstrated that B cell activating factor (BAFF) signaling is critical for the maintenance of mature B cells. However, the contribution of the alternative NF-kB subunits that are activated downstream of BAFF remained unclear, especially in regards to their specific target genes. We have identified critical, B cell-intrinsic roles for RELB and NF-kB2 in the maintenance of mature B cells. In response to BAFF, these subunits were found to control the expression of anti-apoptotic genes, genes that ensure correct positioning within the B cell niche, and genes involved in promoting B–T cell interactions that allow effective antigen-mediated activation. During the GC B cell reaction, light zone (LZ) B cells undergo affinity-based selection mediated by T follicular helper (Tfh) cells. A subset of LZ B cells show activation of the NF-kB signaling cascade, suggesting a critical role for NF-kB in the selection of high-affinity GC B cells. We here report that GC B cell development occurred normally in mice with conditional deletion of either relb (RELB) or nfkb2 (NF-kB2) in GC B cells. In contrast, the simultaneous ablation of both subunits caused rapid involution of established GCs, similar to what has been observed for ablation of the canonical NF-kB transcription factor subunit c-REL. Intriguingly, RNA-sequencing analysis of relb/nfkb2-deleted GC B cells revealed no overlap between the genes controlled by RELB/p52 and c-REL within GC B cells. This suggests that signaling through the separate NF-kB pathways in GC B cells results in the expression of different biological programs that are independently required for the maintenance of the GC reaction. In addition, we observed that human PCs and PC precursors within the LZ showed high protein levels of NF-kB2 compared to surrounding lymphocytes, suggesting a biological role for this subunit in PCs. Indeed, ablation of nfkb2 alone in GC B cells led to a dramatic decrease in antigen-specific serum IgG1 and antigen-specific IgG1-secreting cells. Interestingly however, the mice developed normal frequencies of PCs, suggesting a role for NF-kB2 in PC physiology rather than differentiation.

Introdução: O Diabetes Mellitus é doença que apresenta elevada incidência e prevalência na população em diversas partes do mundo. Estudos experimentais sugerem que o estresse oxidativo esteja envolvido na patogênese e na progressão dela. Objetivo: Investigar os efeitos da utilização exógena do antioxidante orgoteína (SOD Cu/Zn) sobre o estresse oxidativo, ativação do fator de transcrição nuclear kappa B (NFκB) e expressão da óxido nítrico sintase induzível (iNOS) hepática no modelo experimental de diabetes mellitus (DM). Métodos e Resultados: Foram utilizados 28 ratos machos Wistar, divididos em quatro grupos: controle (CO), controle tratados com orgoteína (CO+ORG), diabéticos (DM) e diabéticos tratados com orgoteína (DM+ORG). A dose utilizada da ORG (orgoteína ®) foi de 13 mg/Kg de peso corporal durante os sete últimos dias de experimento através de injeção subcutânea. O DM foi induzido por injeção de estreptozotocina (i.p.,70 mg/kg) e, após sessenta dias, foi avaliada a lipoperoxidação hepática através das substâncias que reagem ao ácido tiobarbitúrico (TBARS- nmoles/mg de proteína), a atividade das enzimas antioxidantes catalase (CAT-pmoles/mg de proteína), superóxido dismutase (SOD-U/mg de proteína) e glutationa peroxidase (GPx- nmoles/mg de proteína). Também foi realizada a medida de nitritos e nitratos (mM de NO2 e NO3). As expressões da p65 do NFκB e da iNOS foram avaliadas pela técnica de Western blot e quantificadas por densitometria em relação à percentagem do controle. Resultados: Houve aumento na lipoperoxidação hepática no grupo DM e redução significativa no grupo DM+ORG (0,36±0,15 vs 0,18±0,04; p<0,01). A atividade da enzima CAT apresentou aumento no grupo DM e redução significativa no grupo DM+ORG (p<0,001), enquanto a atividade da SOD e da GPx apresentaram redução no DM e aumento no grupo DM+ORG, respectivamente (p<0,001 e p<0,05). A medida de nitritos e nitratos apresentou redução no DM e aumento no grupo DM+ORG (1,47±0,61 vs 2,29±0,20; p<0,05) enquanto a expressão da iNOS foi 32% maior no grupo DM em relação ao grupo CO e 53% maior no grupo DM+ORG, quando comparado com o grupo DM (p<0,01). A p65 foi 37% mais expressa no DM (p<0,05) e sem diferença estatística, quando comparado o grupo DM com o grupo DM+ORG. Conclusão: O tratamento com orgoteína reduziu o estresse oxidativo hepático em animais diabéticos, mesmo não alterando o fator de transcrição nuclear NFкB. A orgoteína também aumentou a bioatividade do NO, provavelmente, devido ao aumento da atividade, dismutando o radical superóxido, e devido ao aumento da expressão da iNOS. / Aim: To investigate the effects of exogenous antioxidant orgoteína on oxidative stress, activation of nuclear transcription factor kappa B (NFκB), and hepatic expression of inducible nitric oxide synthase (iNOS) in the experimental model of diabetes mellitus (DM). Methods: 28 male Wistar rats divided in four groups were used: control (CO), controls treated with orgoteína (CO+ORG), diabetics (DM), and diabetics treated with orgoteína (DM+ORG). Orgoteína (orgotein®, 13 mg/Kg body weight was administered subcutaneously for the last 7 days of the trial. DM was induced by a single streptozotocin injection (i.p.,70 mg/kg), and 60 days later, we evaluated liver lipoperoxidation through thiobarbituric acid reactive substances (TBARS- nmoles/mg of protein) and activity of antioxidant enzymes catalase (CAT-pmoles/mg of preotein), superoxide dismutase (SODU/ mg of protein) and glutathione peroxidase (GPx- nmoles/mg of protein). Nitrites e nitrates (mM NO2 and NO3) were also measured, and p65 of NFκB and iNOS expressions were evaluated by Western blot and quantified by densitometry as compared to control percentage. Results: Liver peroxidation was increased in the DM group and significantly decreased in the DM+ORG group (0.36±0.15 vs 0.18±0.04; p<0.01). CAT activity was increased in the DM group and significantly decreased in the DM+ORG group (p<0.001), whereas SOD and GPx activity were decreased in the DM group and increased in the DM+ORG group, respectively (p<0.001 and p<0.05). Nitrite and nitrate measures were reduced in the DM and increased in the DM+ORG group (1.47±0.61 vs 2.29±0.20; p<0.05), while iNOS expression in the DM group was 32% greater than in the CO and 53% greater in the DM+ORG group than in the DM group (p<0.01). P65 expression was 37% higher in the DM (p<0.05), and there was no significant difference between the DM and DM+ORG groups. Conclusion: Orgoteína treatment reduced liver oxidative stress in diabetic animals, even though it did not change NFкB. Orgoteína also increased NO bioactivity, probably by the increased dismutation of the superoxide radical and by increase in iNOS expression.

A utilização de plantas com fins medicinais, para o tratamento, a cura e a prevenção de doenças é uma das formas mais antigas de prática medicinal da humanidade. A espécie Croton cajucara BENTH (CcB) é uma planta nativa e endêmica da região Amazônica, onde é popularmente conhecida como “sacaca”. É muito utilizada na medicina popular, sob a forma de chás da casca e de folhas no tratamento de diversas doenças, como o diabetes. Estudos experimentais e clínicos sugerem que o estresse oxidativo esteja envolvido na patogênese e na progressão do diabetes. Este estudo tem como objetivos avaliar os efeitos do extrato aquoso da casca do CcB sobre as alterações hepáticas, os níveis plasmáticos de glicose, triglicerídeos (TG) e colesterol, os efeitos genotóxicos, o estresse oxidativo, a concentração de nitritos e nitratos e a ativação da subunidade p65 do fator de transcrição nuclear Kappa B em fígado de animais diabéticos induzidos por estreptozotocina (STZ). Foram utilizados ratos machos Wistar, divididos em seis grupos com dez animais cada: controle (CO); controle com tratamento durante cinco dias com CcB (CcB5D); controle com tratamento durante 20 dias com CcB (CcB20D); diabéticos (DM); diabéticos com tratamento durante cinco dias com CcB (DM5D); e diabéticos com tratamento durante 20 dias com CcB (DM20D). O DM foi induzido por administração intraperitonial de STZ na dose de 70mg/Kg. O extrato aquoso (EA) foi preparado com 5g da casca do CcB/100mL H2O e administrado na dose de 1,5mL intragástrica. Após 60 dias, foi coletado sangue do plexo retro-orbital para as análises das enzimas séricas: AST, ALT, FA e dosagem de glicemia, triglicerídeos e colesterol. Para avaliar a atividade genotóxica do extrato, foi utilizado o teste de micronúcleos (MN) em medula óssea. O homogeneizado do fígado foi utilizado para avaliação de lipoperoxidação (LPO) através das substâncias que reagem ao ácido tiobarbitúrico (TBARS) e para avaliação da atividade das enzimas antioxidantes SOD, CAT, GPx e GSH, avaliação dos metabólitos do óxido nítrico (nitritos e nitratos totais) e a expressão nuclear da subunidade p65 do NF-kB. A análise das enzimas séricas mostrou que houve aumento de ALT e FA nos animais DM em relação aos grupos CO, e que a ALT apresentou-se diminuida nos animas DM tratados durante cinco e 20 dias. O tratamento com CcB não diminuiu os níveis da glicemia e do colesterol, houve, porém, redução significativa nos níveis de TG nos animais diabéticos tratados durante cinco e 20 dias. O tratamento com CcB não diminuiu os níveis da glicemia e do colesterol, houve, porém, redução significativa nos níveis de TG nos animais diabéticos tratados durante cinco e 20 dias. O EA do CcB mostrou-se destituído de ação genotóxica. Houve aumento no TBARS e na SOD em animais DM e diminuição significativa nos animais diabéticos tratados durante cinco e 20 dias. Por outro lado, verificou-se aumento de TBARS e da atividade da SOD no grupo CO20D. A atividade da CAT e da GPx não apresentaram diferenças significativas entre os grupos estudados. A GSH apresentou-se diminuída nos animais diabéticos em relação aos controles e ao grupo DM5D. Os animais diabéticos apresentaram aumento nos níveis dos metabólitos do óxido nítrico em relação aos animais controles, e a administração do EA do CcB não reverteu essa situação. Houve ativação da expressão nuclear do p65 nos animais diabéticos que foi atenuada nos animais que receberam o EA do CcB. O tratamento dos ratos diabéticos com o EA de CcB parece melhorar os níveis de TG, não reduziu, no entanto, a glicemia e o colesterol, provavelmente por se tratar de um modelo de diabetes crônico. O tratamento diminuiu a LPO e a atividade da SOD, provavelmente devido à atividade antioxidante do EA do CcB como varredor de radicais ânion superóxido. Os resultados mostram que, em situações onde não há estresse oxidativo, o uso prolongado de CcB comporta-se como pró-oxidante e, em situações onde existe estresse oxidativo, o tratamento com o CcB pode possuir ação antioxidante varredora de radicais livres. Além disso, os resultados parecem sustentar a hipótese de que o estresse oxidativo presente do DM estimula a expressão do NF-kB e que administração do EA do CcB reduz essa expressão. / The use of plants for medical purposes in the treatment, cure and prevention of diseases is one of the oldest medical practices of mankind. Croton cajucara BENTH (CcB) is a vegetal species that is native and endemic in the Amazonian region, where it is popularly known as “sacaca”. Bark and leaf infusions of sacaca are widely used in folk medicine to treat many diseases, such as diabetes. Experimental and clinical studies suggest that oxidative stress is involved in the pathogenesis and progress of diabetes. The present study was designed to evaluate the effects CcB aqueous extracts (AE) on hepatic changes, plasma levels of glucose, triglycerides (TG) and cholesterol, genotoxic effects, oxidative stress, nitrites and nitrates levels, and on activation of the p65 subunit of nuclear Kappa B transcription factor (NF-B) in the livers of animals made diabetic by streptozotocin (STZ) administration. Six groups of 10 male Wistar rats each were used as follows: controls (CO); controls with 5-day treatment with CcB (CcB5D); controls with 20- day treatment with CcB (CcB20D); diabetics (DM); diabetics with 5-day treatment with CcB (DM5D); and diabetics with 20-day treatment with CcB (DM20D). DM was induced by intraperitoneal administration of STZ (70mg/Kg). The aqueous extract was obtained using 5g of CcB bark for 100ml H2O and intragastrically administered at a dose of 1.5mL. After 60 days retro orbital blood samples were obtained for analysis of serum enzymes AST, ALT, FA and glucose, triglyceride and cholesterol levels determination. The genotoxic activity was evaluated using the micronucleus assay (MN) in bone marrow. The liver homogenates were used for evaluation of lipoperoxidation (LPO) through thiobarbituric acid reactive substances (TBARS), antioxidant enzymes SOD, CAT, GPx and GSH, nitric oxide metabolites (total nitrites and nitrates) and nuclear expression of p65 of NF-kB. The analysis of serum enzymes showed that there was an increase in ALT and AP in DM animals as compared to CO groups, and ALT was decreased in DM animals treated for 5 and 20 days. The treatment with CcB did not reduce the glycemia and cholesterol level, but there was a significant reduction in the TG levels in DM animals treated for 5 and 20 days. The CcB aqueous extract failed to show any genotoxic action. TBARS and SOD were increased in DM animals and significantly decreased in diabetic animals treated for 5 and 20 days. On the other hand, TBARS and SOD activity were increased in the CcB20D group. CAT and GPx activities were not significantly different across the studied groups. GSH was decreased in the diabetic animals as compared to controls and the DM5D group. The diabetic animals presented an increase in the metabolite levels of nitric oxide as compared to controls, and the administration of CcB AE failed to reverse this situation. There was activation of p65 nuclear expression in the diabetic animals, which was attenuated in the animals receiving the CcB AE. The treatment of diabetic rats with CcB appears to improve TG levels, but it did not reduce glycemia and cholesterol levels, probably because the study dealt with a chronic diabetes model. The treatment decreased LPO and SOD activity, probably because of CcB’s antioxidant activity as scavenger of superoxide anion radicals. The results show that in situations where there is no oxidative stress the extended use of CcB behaves acts as a pro-oxidant and in situations where there is oxidative stress the treatment with CcB may be an antioxidant scavenger of free radicals. Furthermore, the results seem to support the hypothesis that the oxidative stress seen in DM stimulates NF-B expression and that CcB AE administration reduces such expression.

TNF defers apoptosis in macrophages undergoing spontaneous or pharmacologically (thapsigargin, ceramide, CCCP, etoposide or cisplatin)-induced apoptosis, as determined by measurements of caspase-3 activity and annexin-V staining (Chapter 2). The action requires TNF interaction with TNF-R1, not TNF-R2. Survival is uniquely reliant on the activity of the NF-B signaling pathway, and does not require activities arising from the PI3K/Akt, JNK, ERK, p38 MAP kinase or iNOS pathways (Chapter 3). Further, the general anti-apoptotic property of TNF and its specific antagonism of CCCP-induced apoptosis led to the finding that TNF action prevents cytochrome c release. This protection is likely mediated through effects on components of the MPTP itself, as TNF exhibited functional redundancy with the pore inhibitor cyclosporin A, and did not modify upstream events that promote MPTP opening during apoptosis, namely ROS production, cytosolic Ca2+ increase, or a reduction of total ATP (Chapter 4). Subsequent experiments with the mRNA synthesis inhibitor, actinomycin D, and the translation inhibitor, cycloheximide revealed that the protein(s) responsible for TNF-induced survival was transcribed and translated within 1 hr. However, western analyses provided no convincing evidence of the involvement of Mn-SOD, cIAP-1, XIAP, Bcl-2 or A1 in TNF cytoprotection (Chapter 5). Rather, microarray experiments identified the consistent induction of an early response gene, pim-1, within 30 min of TNF exposure (Chapter 6). This result was verified at the protein level with a specific Pim-1 antibody. Evidence was also found for induction of the anti-apoptotic protein A20, but only at mRNA level. Parthenolide, wortmannin, SP600125, PD98059, SB203580 or L-NAME1 acted against TNF-induced Pim-1 expression in a pattern that exactly matched the effects of these inhibitors on TNF-induced survival. That is, only parthenolide-mediated inactivation of NF-B abolished TNF-induced induction of Pim-1. TNF also stimulated the rapid phosphorylation (inactivation) of the pro-apoptotic BH3-only protein, Bad at Ser112 in a manner sensitive to NF-B inhibition, but not PI3K/Akt, JNK, ERK or p38 MAP kinase inhibition (Chapter 7). As Bad is a known substrate of Pim-1 and Bad 1 Parthenolide, wortmannin, SP600125, PD98059 and SB203580 are inhibitors of the NF-B, PI3K/Akt, JNK, ERK and p38 MAP kinase pathways, respectively. L-NAME inhibits iNOS. NF-B- and mitochondria-linked signaling events that contribute to TNF action in deferring physiological and chemotherapeutic drug-induced apoptosis in macrophages ii phosphorylation occurred coincident with Pim-1 upregulation, it is likely that Pim-1 kinase activity mediates the inactivation of Bad. The overall data therefore supports a model in which TNF ligation of TNF-R1 at the cell surface results in intracellular NF- B activation, leading to the induction of Pim-1 mRNA and protein, and the ensuing phosphorylation of Bad. Inactivation of pro-apoptotic Bad increases the resistance threshold of mitochondria to apoptotic insults, thereby reducing the occurrence of mitochondrial permeability transition, cytochrome c release and subsequent caspase-3 activation.

Map Theory est une extension équationnelle du lambda-calcul non-typé conçue par Klaus Grue pour être une fondation commune de l'informatique et des mathématiques. Elle permet en particulier une interprétation complète du calcul des prédicats et de ZFC+FA, où ZFC est la théorie de Zermelo-Fraenkel, et FA est l'axiome de bonne fondation usuel. Toutes les notions primitives de la logique du premier ordre et de la théorie des ensembles, valeurs de vérité, connecteurs, quantificateurs, appartenance et égalité, y sont traduites par des termes du lambda-calcul enrichi de quelques constantes. De plus, Map Theory permet de représenter les types de données inductifs et de donner un sens calculatoire immédiat à tous les constructeurs ensemblistes usuels. La version initiale de Map Theory par K. Grue ne considère cependant que les ensembles (ou classes) bien-fondée relativement à la relation d'appartenance. Dans le cadre du renouveau d'intérêt pour l'antifondation induit par les developpements récents de l'informatique théorique, nous montrons dans notre thèse qu'il est possible d'élaborer une version antifondée de Map Theory qui prenne en compte l'existence des objets non-bien-fondés, et qui permette de raisonner sur ces objets par co-induction. Ce nouveau système ouvre la possibilité d'une représentation directe des types de données co-inductifs, et de la modèlisation des phènoménes et processus circulaires. Dans une première partie, nous présenterons l'axiomatisation MTA de ce nouveau système, et nous montrerons que ZFC+AFA, où AFA est l'axiome d'Antifondation de Aczel-Forti-Honsell, y est interprétable syntaxiquement. Dans la deuxième partie, nous montrerons la consistance de MTA relativement à ZFC+SI, où SI est l'axiome exprimant l'existence d'un cardinal fortement inaccessible.

Thesis (Ph. D.)--University of Chicago, Committee on Immunology, June 2003. / Includes bibliographical references. Also available on the Internet.

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 147-163).

The long-term trend regarding wood is an increase in price. Because wood contributes to a large part of production costs, the efficient utilisation of wood is greatly desired to reduce production costs for kraft pulp producers. During the 1990s, the development of improved modified kraft cooking began, which led to higher yields. There was also a trend of terminating kraft cooking at a higher kappa number to maximise the overall yield. For hardwood, the defibration point became a critical setback in allowing this termination at a high kappa number. This thesis discusses how this issue has been tackled in the laboratory by using improved modified kraft cooking combined with extended impregnation to enable a decrease in reject content and shift the defibration point towards a higher kappa number for hardwood. This lab concept is referred to as extended impregnation kraft cooking (EIC), and this thesis reveals that EIC cooking efficiently reduces the reject content for both birch and eucalypt. By using EIC cooking, the defibration point was shifted to a kappa number of ca. 30 from ca. 20 using conventional kraft cooking. This study demonstrates the great potential for achieving a higher overall yield for eucalypt by terminating the EIC cooking at a high kappa number, but with the conditions used in this thesis, no improvement in yield was observed for birch.   An important issue is that the termination of kraft cooking at high kappa number increases the demand for extended oxygen delignification to reach a similar kappa number into bleaching, i.e., due to cost and environmental reasons. Extended oxygen delignification was shown to be possible for both birch and eucalypt EIC pulps (i.e., from kappa number 27 to 10) with an acceptable pulp viscosity number.   The other part of this thesis addresses aspects regarding the limitations in oxygen delignification. It has previously been shown in the literature that a high xylan yield of kraft cooking could negatively affect the efficiency of subsequent oxygen delignification. In this work, the increased xylan content in eucalypt kraft pulp within the range of 8–18% had only a marginally negative impact on the oxygen delignification efficiency after correcting for the HexA contribution to the kappa number. It is also desired to extend the oxygen delignification towards lower kappa number, i.e., below kappa number 10 to decrease the bleaching chemical requirement. In this study, the hypothesis that the reduced efficiency of oxygen delignification at low kappa numbers could partly be due to the formation of oxidisable carbohydrate-related structures (i.e., HexA and/or other non-lignin structures) was also tested. No formation was established. On the other hand, a final oxygen delignification stage in the bleaching could be an attractive alternative for reducing yellowing and enhancing brightness; in fact, this has led to the development of a patent (SE 528066). / Ved står för en stor del av produktionskostnaderna vid framställning av sulfatmassa. Då vedpriserna har ökat genom åren är ett effektivt utnyttjande av veden önskvärt för att kunna sänka produktionskostnaderna. Under 1990-talet förbättrades den modifierade sulfatkokningen vilket innebar möjlighet till högre massautbyte. För att maximera massautbytet styrdes kokningsprocessen mot ett högre kappatal. Detta har visat sig vara svårare för lövved än för barrved, eftersom defibrerbarhetspunkten utgör ett kritiskt hinder. I denna avhandling har laborationsstudier utförts där förbättrad modifierad sulfatkokning kombinerats med förlängd impregnering för att kunna sänka spethalten och därmed förskjuta defibrerbarhetspunkten mot ett högre kappatal. Detta koncept kallas för extended impregnation kraft cooking (EIC). EIC-kokning visade sig vara en effektiv metod för att minska spethalten hos björk och eukalyptus. Med EIC-kokning kunde defibrerbarhetspunkten höjas från cirka 20 till cirka 30. I denna avhandling klarläggs att det finns stora möjligheter att öka massautbytet för eukalyptus genom att avsluta sulfatkoket vid ett högre kappatal. För björk kunde ingen ökning av massutbytet uppnås genom ovanstående metod.   Vid ett högre kappatal efter sulfatkoket ställs även krav på förlängd syrgasdelignifiering, för att kunna behålla samma kappatal in till blekeriet. Det visade sig vara fullt möjligt att förlänga syrgasdelignifieringen för de EIC-kokade björk- och eukalyptusmassorna (d.v.s. från kappatal 27 till 10) med accepterad massaviskositet.   Den andra delen av avhandlingen tar upp aspekter på syrgasdelignifieringens begränsningar. Tidigare studier har visat att ett högre utbyte av xylan vid sulfatkokning kan vara negativt för syrgasdelignifieringens effektivitet.  I denna studie har det påvisats att en ökad xylanhalt i intervallet 8–18 procent i eukalyptusmassa endast har en marginell negativ inverkan på syrgasdelignifieringens effektivitet efter att kappatalet korrigerats för HexA. Det är önskvärt att förlänga syrgasdelignifieringen till ett lägre kappatal än 10 för att minska förbrukningen av blekkemikalier. I den här studien prövades hypotesen att syrgasdelignifieringens begränsningar vid låga kappatal, under 10, delvis skulle kunna bero på bildning av oxiderbara kolhydratrelaterade strukturer (d.v.s. HexA och/eller andra okända ”non-lignin”-strukturer). Ingen bildning kunde dock observeras. Däremot indikerades att ett syrgassteg i slutet av bleksekvensen skulle kunna vara ett eftersträvansvärt alternativ för minskad eftergulning och ökad ljushet, vilket ledde till ett patent (SE 528066). / QC 20120507

Njurarna är ett organsystem med viktiga funktioner som exempelvis utsöndring av flertalet vattenlösliga substanser. För att sjukdomssymtom ska uppträda krävs mer än tre fjärdedelars bortfall av njurfunktionen, eftersom njurarna har en enorm reservkapacitet. Genom att analysera bland annat proteinerna albumin, immunoglobulin G, kappa och lambda i urin utreds om njurfunktionen fungerar som den ska. Analys av dessa proteiner kan ske med analysinstrumenten IMMAGE 800 från Beckman Coulter och BN ProSpec från DADE BEHRING. Båda dessa analysinstrument använder sig av metoden nefelometri, som är en metod där ljusspridning i en vätska eller gas kan mätas. Syftet med föreliggande studie var att analysera urinprover på både IMMAGE 800 och BN ProSpec och sedan jämföra resultaten. Under denna studie kalibrerades standardkurvor, genomfördes kvalitetskontroller och 37 prov analyserades. Samma prov analyserades flera gånger, både under samma dag och vid ett antal kommande dagar för att erhålla precisionen. Korrelationskoefficienten blev 0,999 för U-albumin; 0,998 för U-IgG; 0,947 för U-kappa och 0,883 för U-lambda. ProSpec kan således användas vid analys av U-albumin, U-IgG, U-kappa och U-lambda då den uppfyller EQUALIS kvalitetsmål.

Two novel personal calibration procedures that do not require active user participation are presented. These procedures, in conjunction with a state-of-the-art remote eye-gaze tracking (REGT) technology, allow estimation of the angle between the optical and visual axes (angle kappa) automatically without explicit/active user involvement. The first algorithm for the binocular estimation of angle kappa (BEAK) is based on the assumption that at each time instant both eyes look at the same point on a surface with a known geometry (e.g., a computer monitor). The sensitivity of the BEAK procedure to the geometry of the observation surface and to the noise in the estimates of the optical axis is studied both analytically and in computer simulations. Experimental results with 4 adult subjects suggest that with the current REGT technology angle kappa can be estimated with an RMS error of 0.5°. The second personal calibration algorithm (‘calibrate and validate’, CaVa) adopts a probabilistic approach to the estimation of angle kappa in infants. Even though the presentation of visual stimuli at known positions is part of the procedure, the CaVa algorithm does not require/assume continuous fixation on the presented targets. If an infant attends to roughly half of the presented targets, angle kappa can be estimated accurately and with high confidence. In experiments with five babies, the average difference between repeated measurements of angle kappa was 0.04 ± 0.31°. The second part of the thesis describes two methods for automated measurement of eye misalignment in adults and infants. These methods are based on the user-calibration-free (UCF) technology presented in the first part of the thesis. The first method is based on the clinical Hirschberg test. It is shown that the UCF-REGT technology can improve significantly the accuracy of the Hirschberg test by enabling the estimation of subject-specific parameters (the Hirschberg ratio and angle kappa) in infants. The maximum error in the estimation of the horizontal and vertical components of eye misalignment in five orthotropic infants was shown to be less than 1°, which is significantly better than the accuracy of a standard clinical Hirschberg test. Finally, a novel Eye-Tracker Based Test (ETBT) for the estimation of the maximum (manifest + latent) angle of deviation is presented. ETBT is based on the UCF-REGT system. ETBT allows free head movements and does not require continuous fixation on specific targets. Experiments with 22 adult subjects demonstrated a good agreement of 0.7 ± 1.7° between ETBT and the gold-standard clinical procedure—the altenate prism and cover test. A pilot study with 5 orthotropic infants and one infant with strabismus demonstrated that the ETBT can be used in infants.