The broad aim of the work presented in this thesis was to examine the relationship between the mineral and organic phases of calcium oxalate monohydrate (COM) crystals, which are the principal components of human kidney stones. The results presented, clearly demonstrate the presence of some amino acids and urinary proteins in the crystals and suggest a role for intracrystalline proteins in urolithiasis. The adsorptive affinities of twenty amino acids to COM, calcium hydrogen phosphate, tricalcium phosphate and hydroxyapatite were assessed over the physiological urinary pH range (pH 5-8) in aqueous solutions. In all cases adsorption was strongest at pH 5 and decreased as the pH increased as a result of the increasing negative charge of both substrate and adsorbate. Binding was higher to COM than to the phosphate minerals, owing to differences in the surface charge or coordination-site availability. Aspartic acid (Asp), glutamic acid (Glu) and y- carboxyglutamic acid (Gla), which each have at least two carboxyl groups, exhibited the highest binding affinities, suggesting that binding occurs by chelation. Further, binding affinity was reasoned to result from the ability of the zwitterions of Asp, Glu and Gla to adopt favourable conformations in which two carboxyl groups, and possibly the amino group, can interact with the mineral surface without further rotation. Although free amino acids are unlikely to fulfil a prominent inhibitory role in stone pathophysiology, they could, nonetheless, fulfil an important function as terminal residues or as exposed components of calcium-binding domains of proteins involved in stone formation. The existence of intracrystalline proteins and amino acids in COM crystals was demonstrated by Synchrotron X-ray Diffraction (SXRD) analysis. / Non-uniform strains and crystallite sizes were derived from SXRD whole pattern line widths using Rietveld analysis, which showed an increase in average non-uniform strain and a decrease in average crystallite size. These were attributed to intracrystalline molecules. Occluded molecules were Glu, Gla, human prothrombin (PT) and to a lesser extent, human serum albumin (HSA), as well as crystal matrix extract (CME), which comprises a complex mixture of soluble organic molecules remaining after demineralization of COM crystals grown in centrifuged and filtered (CF) urine. COM grown in CF urine possessed greater non-uniform strain and smaller crystallite size than COM grown in ultrafiltered (UF) urine, indicating that the majority of intracrystalline macromolecules in crystals derived from CF urine were >10kDa in molecular mass. Asp, AspAsp, GluGlu and Tamm Horsfall glycoprotein (THG) were non-occluded molecules. Proteinase treatment of COM crystals grown in CF urine produced a marked decrease in non-uniform strain and an increase in crystallite size, suggesting that smaller crystallite material, more intimately associated with proteins than the bulk COM, was liberated during the treatment. A reciprocal relationship was found between non-uniform strain and crystallite size, which was dependent upon the type of molecule(s) in which the COM crystals were grown. For a given increment in non-uniform strain, the corresponding decrease in crystallite size was found to be considerably greater for occluded macromolecules, than for amino acids. This difference was attributed to the capacity of macromolecules, once incorporated into the crystal, to disrupt a larger volume of the mineral bulk than amino acids. Alternatively, unlike amino acids, macromolecules might possibly stabilise an amorphous phase. / Amorphous contributions resulting from the occlusion of PT and molecules from CF urine and UF urine in COM were found to range between 5-9%. The SXRD data derived from the COM crystals were further analysed for anisotropy using Williamson-Hall plots and individual peak analysis (SHADOW). Crystals grown in distilled water COM (distilled water) and COM (Asp, AspAsp, GluGlu, Gla, HSA, THG and PT) were isotropic with respect to both non-uniform strain and crystallite size. Although COM (Glu) and COM (UF) were isotropic with respect to non-uniform strain, the crystallite sizes were smaller along the (100) and (001) principal axes, respectively. COM (CF urine) and COM (CME) were also anisotropic, but with respect to crystallite size, with the shortest lengths occurring along the (100) and (001) axes. The absence of anisotropy in non-uniform strain was ascribed to experimental error. The data also showed that stacking faults contributed significantly to crystal disorder. Largest stacking faults, highest non-uniform strain and lowest crystallite sizes were generally found along the (13i) plane. Computer- generated models showed that molecules as large as proteins could not effectively be incorporated along the (13i) plane in COM. It was concluded therefore, that they transmit disorder from the principal (100,010, 001) planes in the crystal to the (13i) plane by diagonal sliding of one or more rows of oxalate ions, calcium ions and water molecules. SXRD single peak and whole pattern analysis of COM crystals grown in aqueous solutions of increasing concentrations of PT, HSA, CME and Gla showed that non- uniform strain increased, crystallite size decreased and stacking faults increased, to limiting values. / This was also found for crystals grown in UF urine containing CME and HSA. When crystals with occluded proteins were treated with proteinase K, their stacking faults and non-uniform strain decreased, and crystallite size increased, indicating that the non-crystalline material is more intimately associated with the protein and is physically removed or solubilised when the protein is destroyed. FESEM observations of the internal architecture of fractured CaOx crystals grown in human urine and synthetic solutions containing PT, revealed an inhomogeneous microstructure containing low density zones not observed in COM crystals grown in water or UF urine. Proteolytic treatment of the fractured crystals, created an internal honey combed structure that replaced the “low-density” zones. A timed growth study showed the internal ultrastructure of urinary COM crystals depended to a significant extent, upon the ratio of crystal-binding proteins to the available quantities of solute ions during growth. Dissolution studies of COM crystals showed that the process obeyed the Shrinking Core model and was therefore surface area-dependent. Pure COM dissolved more rapidly than crystals derived from UF urine, which dissolved at a faster rate than crystals precipitated from CF urine. This was attributed to shielding of the exposed COM surface by occluded molecules, which would reduce the effective surface area and slow dissolution. There is also the possibility that the macromolecules would have bound to the ions and retard their release into solution. The use of proteinase inhibitors verified the presence of proteinases in fresh urine and showed that they were capable of attacking proteins occluded in COM, in particular, proteins with Mr > 10kDa. / Although COM (CF) crystals were more difficult to dissolve than COM (UF) crystals in aqueous solutions, they were far more susceptible to endogenous proteolytic degradation in urine. Collectively, these findings have formed the basis of a novel hypothesis, which proposes that the type and concentration of urinary proteins incorporated inside CaOx crystals are fundamental to the disposal of CaOx crystals precipitated and retained within the renal system, and may therefore play an important role in the prevention of urolithiasis.

Development of the adult form requires coordinated growth and patterning of multiple traits in response to local gene activity as well as global endocrine and physiological effectors. In recent years the zebrafish has been utilized as a favorable animal model as a step towards dissecting and better understanding these postembryonic developmental processes. One of the more powerful methods utilized in zebrafish has been the identification of new gene functions through the use of mutant screens. The nutria mutant was recovered from one such screen to identify postembryonic defects in pigment pattern, growth and metamorphosis. These mutants exhibited a pigment cell defect, touch unresponsiveness and severe growth retardation. Here I will discuss my work towards dissecting the underlying developmental processes governing the phenotypic changes in nutria mutants. I characterize gross alterations in skeletal development in nutria mutants that lead to accelerated endochondral ossification but delayed intramembranous ossification. I show that the nutria phenotype results from mutations in trpm7, which encodes a transient receptor potential (TRP) family member that functions as both a cation channel and a kinase. I find trpm7 expression in the fish-specific, ion homeostasis-regulating gland known as the corpuscles of Stannius (CS), and in the mesonephric kidney. I show that mutants also develop kidney stones. Together these results suggest a role for trpm7 activity in regulation of physiological ion homeostasis. Next I confirm that role by identifying late-embryonic and early larval defects in the CS and the kidney, two organs that regulate physiological ion homeostasis. I demonstrate the early larval detection of kidney stones in trpm7 mutants and show that their appearance is presaged by decreased levels of total calcium and magnesium. Furthermore I establish a link between trpm7 function in the CS and stanniocalcin1 (stc1), a potent molecular regulator of calcium homeostasis. Finally, using transgenic overexpression and morpholino-oligonucleotide knockdown, I demonstrate that stc1 modulates calcium and magnesium levels in trpm7 mutant and wild-type backgrounds. Together these analyses establish postembryonic roles for trpm7 function in growth, skeletogenesis, kidney function, and physiological ion homeostasis. / text

Bakgrund: Omkring 10-15 % av befolkningen, oftast i arbetsför ålder, riskerar att någon gång drabbas av njursten. Nationella riktlinjer för njurstensbehandling saknas, men studier stödjer behandling inom 48 timmar för snabb symtomlindring och minskade besvär för patienten. Inom studerad verksamhet var tiden från diagnos till behandling lång och återinläggningarna var många, varför ett förbättringsarbete initierades. Syfte: Syftet med förbättringsarbetet var att halvera tiden från diagnos till behandling för patienter med akut behandlingskrävande uretärsten, samt minska negativa effekter relaterade till obehandlad uretärsten. Vidare syftade studien av förbättringsarbetet till att beskriva ett tvärprofessionellt teams erfarenheter av aktuellt förbättringsarbete gällande patienter med uretärsten. Metod: Ett tvärprofessionellt team bedrev förbättringsarbetet med stöd av Nolans modell för förbättringsarbete, vilket studerades genom en deskriptiv fallstudie med induktiv ansats. Effekterna av förbättringsarbetet utvärderades med Statistical Process Control (SPC). Vidare studerades teamets erfarenheter genom gruppintervjuer, och skriftliga berättelser vars data analyserades och sammanställdes genom kvalitativ innehållsanalys. Resultat: Målet med behandlingstiden uppnåddes inte, men positiva effekter för patienterna uppmättes. ESWL-behandling inom 48 timmar minskade tiden från diagnos till sista behandling. Planering, samarbete, information var nödvändigt för att lyckas med ett förbättringsarbete, men i kontexten fanns motsättningar, vilket försvårade arbetet, så som hög arbetsbelastning och bristande rutiner. Vidare beskrevs en bristande helhetssyn inom verksamheterna kring patienter med njursten, vilket ledde till varierande drivkrafter hos medarbetarna. Slutsatser: ESWL inom 48 timmar förkortade tiden från diagnos till behandling, även hos de patienter som behövde ombehandlas. Utmaningarna i ett förbättringsarbete finns inom olika nivåer, inom en komplex organisation. Riktlinjer och en gemensam målsättning är viktigt för att erbjuda patienterna ändamålsriktig vård i rätt tid. Kommunikation är grundläggande för att lyckas med ett förbättringsarbete. / Background: About 10-15% of the population, mostly at working age, has the risk that at some point be affected by kidney stones. There is a lack of national guidelines for kidney stone treatment, but several studies suggest treatment to start within 48 hours for rapid symptom relief and reduced discomfort for the patient. Within the studied context, the time from diagnosis to final treatment was too long, and the readmission rate was high, why a quality improvement project was initiated. Purpose: The aim of the Quality Improvement project was to halve the time from diagnosis to final treatment for the patients suffering from urethral calculi, and to reduce negative impacts related to an untreated urethral stone. Furthermore the aim of the study was to describe a multi-professional teams’ experiences of actual Quality improvement project. Method: Nolans model for Improvement was used by the team. The effects of the quality improvement were evaluated with Statistical Process Control (SPC). A case study with inductive approach was used. The teams’ experiences was studied through group interviews, and written stories and the data were conducted through qualitative content analysis Results: The goal considering time to final treatment was not achieved, but positive effects for the patients were noted. Extracorporeal Shock Wave Lithotripsy (ESWL) treatment within 48 hours reduced the time from diagnosis to final treatment. Planning, cooperation and communication was the key factors for success for quality improvement. Several barriers was identified in the context, such as; high work load and indistinct routines, which complicated their work. Furthermore a lack of holistic view, considering patients with kidney stone was described, which led to a variation in the driving forces among the employees. Conclusions: ESWL in 48 hours shortened the time from diagnose to final treatment, even if a retreatment was necessary. In a complex organization, the challenges conducting a quality improvement project is on several levels. Well known guidelines and a shared goal for the entire process are important to be able to offer patients appropriate care at the right time.  Communication is fundamental to achieve success.

Bakgrund: Stenar i njurar respektive urinvägar är ett växande problem både i Sverige samt i hela världen. Anledningen till den ökade incidensen av njursten anses vara oklar, däremot kan ändrade kostvanor förslagsvis vara bidragande orsak. Datortomografi (DT) anses vara förstahandsalternativet vid utredning av misstänkta njurstenar där DT har bra förmåga att kartlägga antalet stenar, bestämma storlek samt lokalisera stenarna. Tidigare forskning visar att ultra-lågdos samt lågdos har höga färdigheter i sensitivitet samt specificitet. Däremot avkastas jämförelser av detektering av stenar med standarddos DT. Syfte: Syftet med denna studie var att utforska om hur exponeringen skiljer sig med användandet av låg-dos protokoll i jämförelse med standardprotokoll. Utforska om hur mycket stråldosen kunde sänkas med lågdosprotokoll samt förmågan att detektera stenar. Fokus kommer att ligga på stråldosreducering samt specificitet och sensitivitet i utredning för njurstensmisstanke med datortomografi. Metod: Denna litteraturstudie använder sig av databaser som Pubmed för eftersökningen av vetenskapliga artiklar. Materialet samlades in och bearbetades i enlighet med Forsberg & Wengströms riktlinjer. Resultat: Resultatet till denna studie baseras på 10 valda artiklar från databasen Pubmed. Resultatet presenteras i tre underkategorier, storlek av sten, exponering samt sensitivitet/specificitet. Konklusion: Lågdosprotokoll kunde konkurrera med standardprotokoll gällande detektion av stenar, stenar under 3 mm kan vara svåra att detektera med lågdosprotokoll. Stråldosen reducerades med mer än hälften och bibehöll samtidigt tillräckligt bra kvalitet. Patienter bestrålas med mer än dubbelt så mycket i effektiv dos (ED) med användning av standardprotokoll än med låg-dos protokoll.

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