En France, environ 9,8% de la population souffre de lithiase urinaire. Nous proposons, ici, une nouvelle approche afin de caractériser ces matériaux et d'obtenir une meilleure compréhension de leur formation. Les médecins utilisent principalement des techniques FTIR pour déterminer les principales phases présentes dans une calcification pathologique donnée. Les méthodes de RMN semblent appropriées pour déterminer plus précisément la composition de ces calcifications pathologiques. Très peu d'analyses RMN de calculs rénaux et d'analogues synthétiques ont été réalisées à ce jour.Premièrement, les trois phases d'oxalate de calcium ont été synthétisées (CaC2O4?nH2O avec n = 1, 2, 3) en mettant en ¿uvre des protocoles originaux. L'analyse des spectres 1H, 13C CPMAS et 43Ca MAS à ultra-haut champ magnétique en abondance naturelle permet une identification précise des différentes phases et peut être interprétée en tenant compte du nombre d'inéquivalents des sites cristallographiques. L'hydroxyapatite a été étudiée en parallèle car pouvant également apparaître lors de lithiase urinaire.Enfin, nous montrons les résultats obtenus à partir de DNP MAS à 100 K sur les échantillons synthétiques. L'affinité de la combinaison biradical/solvant reste un facteur limitant pour les matériaux hétérogènes tels que ceux qui sont analysés dans cette étude. Nous devons être en mesure de trouver une combinaison appropriée pour les matériaux multi-composants complexes afin d'obtenir un gain équivalent sur tous les signaux. Finalement, il est démontré qu'il est possible de transposer l'approche méthodologique présentée ci-dessus à l'étude des calculs rénaux. / In France, about 9.8% of the population suffer from urolithiasis. The treatment of kidney stones, composed of 72% of hydrated calcium oxalates (CaC2O4∙nH2O) with n = 1, 2, 3, represents almost 900 million euros in annual spending and it is therefore necessary to understand the in vivo formation of these stones. Here we propose a new approach in order to characterize kidney stones and have a greater understanding of their formation. Physicians primarily use FTIR techniques to determine the major phases present in a given pathological calcification. NMR methods appears suitable to determine more accurately the composition of these pathological calcifications. Very few NMR analyzes of kidney stones and synthetic analogues were conducted to date. In a first step, the three phases of calcium oxalate were synthesized by implementing original protocols. Analysis of the 1H, 13C CP MAS and MAS 43Ca ultra-high magnetic field spectra at natural abundance allow precise identification of the different phases and can be interpreted by taking into account the number of inequivalent crystallographic sites. The hydroxyapatite was studied in parallel as it may also appear in urolithiase. Finally, we show results obtained from DNP MAS at 100 K on the synthetic samples. The affinity of the biradical/solvent combination remains a limiting factor for heterogeneous materials such as those analyzed in this study. We have to be able to find a suitable combination for complex multi-component materials and to obtain an equivalent gain on all signals. In a last step, it is demonstrated that it is possible to transpose the methodological approach presented above to the study of kidney stones.

A nefrolitíase é uma doença comum e recorrente com prevalência mundial variando de 5 a 20%, com pico de incidência entre a 3ª e 4ª década de vida e com maior prevalência em homens (3:1), frequentemente associado a atendimento de urgência. O tratamento da litíase ocorre em duas fases. Inicialmente, no episódio agudo de dor pela passagem do cálculo pelas vias urinárias, cujo objetivo terapêutico é o alívio da dor e a expulsão do cálculo. Para aqueles doentes com cálculos de repetição, o objetivo terapêutico será o de reduzir a formação de novos cálculos. Para ambos os objetivos, o arsenal terapêutico disponível é limitado. Estudos pré-clínicos com o Extrato Padronizado de C. langsdorffi - EPC-AF® (Apis-Flora, Ribeirão Preto, Brasil), um composto vegetal extraído da bioflora nacional, mostraram perfil de segurança e eficácia deste composto como potencial medicamento para o tratamento da litíase renal. Desta forma, o objetivo deste estudo foi o de avaliar o perfil de segurança em humanos e eficácia preliminar do EPC-AF®. Foi realizado um estudo clínico fase I/IIa, randomizado, duplo-cego, comparado com placebo, de dose única de forma ascendente. As doses utilizadas foram de 175 mg, 350 mg,700 mg, 1,4 g e 2,8 g administradas por via oral em dose única após jejum de 12h. Foram estudados grupos de 6 voluntários sadios por dose. Em cada grupo, 4 voluntários receberam de forma randomizada e cega o EPC-AF® e 2 voluntários placebo. O escalonamento para doses mais altas foi feito após a comprovação de que não houve eventos adversos com a dose previamente usada. No total, 30 voluntários sadios foram estudados na Unidade de Pesquisa Clínica do HCFMRP-USP. Foram coletados dados clínicos e laboratoriais para segurança, com destaque para toxicidade renal, onde foram estudados variação das concentrações urinárias de NGAL (neutrophil gelatinaseassociated lipocalin), NAG (N-acetyl-beta-D-glucosaminidase), KIM-1 (Kidney injury molecule-1) e alfa-1-microglobulina, além da dosagem sérica de cistatina C, um marcador da taxa de filtração glomerular. Os dados de eficácia preliminar foramcentrados na análise do perfil bioquímico urinário (pH, cálcio, citrato, oxalato, ácido úrico, magnésio e fosforo) em amostras de urina de 24h, coletadas antes e imediatamente após o uso de EPC-AF® ou placebo. Os resultados obtidos mostraram que o EPC-AF® é seguro nas doses de 175 a 2,8 g por via oral. Não foi observada variações significativas das concentrações de 24h dos principais componentes facilitadores ou inibidores da formação de cálculos urinários / Nephrolithiasis is a common and recurrent disease with a worldwide prevalence varying from 5 to 20%, with a incidence peak between the 3rd and 4th decade of life and with a higher prevalence in men than women (3: 1), often associated with urgent care. The treatment of lithiasis occurs in two phases. Firstly, in the acute episode of pain by the passage of the calculus through the urinary tract, whose therapeutic objective is to relieve pain and expel the stone. For those patients with recurrent stones the therapeutic goal will be reducing the formation of new stones. For both objectives, the available therapeutic arsenal is limited. Preclinical studies with C. langsdorffi standard extract (EPC-AF®, Apis-Flora, Ribeirão Preto, Brazil), an herbal compound extracted from a Brazilian native plant, showed a safety and efficacy profile of this compound as a potential drug for the treatment of renal lithiasis. Thus, the objective of this study was to evaluate the safety profile and the preliminary efficacy of EPC-AF® in healthy volunteers. A phase I/IIa clinical trial, randomized, double-blinded, placebocontrolled single-ascending dose was conducted. The doses used were 175 mg, 350 mg, 700 mg, 1.4 g and 2.8 g administered orally in a single dose after 12 h fasting. Groups of 6 healthy volunteers per dose were studied. In each group, 4 volunteers randomly and blindly received EPC-AF® and 2 volunteers received placebo. The escalation to higher doses was done after the confirmation that there were no adverse events with the dose previously used. In total, 30 healthy volunteers were studied on the General Clinical Research Centre of local teaching Hospital. Clinical and laboratory data were collected for safety, with emphasis on renal toxicity, where urinary concentrations of NGAL (neutrophil gelatinase-associated lipocalin), NAG (N-acetylbeta-D-glucosaminidase), KIM-1 (Kidney injury molecule-1) and alpha-1-microglobulin were measured, in addition to serum cystatin C, a marker of the glomerular filtration rate. Preliminary efficacy data were centered on urinary biochemical profile analysis (pH, calcium, citrate, oxalate, uric acid, magnesium and phosphorus) in 24-hour urinesamples collected before and immediately after use of EPC-AF® or placebo. The results showed that EPC-AF® is safe in doses of 175 to 2.8 g orally. No significant variations in 24-h concentrations of the major components facilitating or inhibiting the formation of urinary stones were observed

Majstorović, Z. Utsöndring av stenbildande substanser i urin – kan stickprov er-sätta dygnsmängder? Examensarbete i Biomedicinsk laboratorievetenskap 15 högskolepoäng. Malmö högskola: Hälsa och samhälle, Utbildningsområde Bio-medicinsk laboratorievetenskap, 2011.Syfte. Utredning av njurstenspatienter omfattar alltid undersökning av utsönd-ringen av stenbildande substanser i urin. Samlingen av urin under ett dygn hos njurstenpatienter innebär ofta problem för patienten eftersom det inte är så sällan att de glömmer samla urin i dunken eller samlar för lång eller kort tid. Syftet med min undersökning är att undersöka om det finns alternativ till att samla urin under 24 timmar i de fall där utsöndringen av stenbildande substanser är konstant över dygnet. Frågeställningen är om utsöndringen av stenbildande substanser kan upp-skattas genom att relatera deras koncentration i urin till koncentrationen av kreati-nin i urin eftersom utsöndringen av kreatinin är relativt konstant över dygnet. I så fall bör koncentrationen av stenbildande substanser i urin kunna relateras till kon-centrationen av kreatinin i urin på samma sätt som vid narkotikaanalys. Metod. Försökspersonerna samlade all urin i exakt 24 timmar. Den första urinportionen sparades i ett separat kärl medan all efterföljande urin samlades i en separat dunk . Efter ca en vecka gjordes en ny urinsamling, denna gång bara i en dunk. Dygnsut-söndringarna jämfördes med varandra och med kreatininindex i stickprovet. Re-sultat. Ett starkt samband fanns mellan kreatininindex av kalcium och dygnut-söndringen av kalcium. Sambandet var något mindre starkt för magnesium och saknades för fosfat och kalium. Slutsats. Resultaten talar mot att kreatininindex generellt kan användas för att skatta utsöndringen av njurstensbildande substanser. Däremot verkar kreatininindex relativt väl förutsäga utsöndringen av kalcium och i viss mån även magnesium. / Majstorović, Z. Secretion of stone-forming substances in the urine - can spot urine sample replace 24 hour urine collection? Degree project in Biomedical Laboratory Science, 15 credits points. Malmö University, Health and Society, Department of Biomedical Laboratory Science, 2011.Objective. Clinical investigation of kidney stone patients always includes moni-toring of the secretion of stone-forming substances in the urine. However, 24 h urine collection is difficult for the patient and prone to error. The purpose of this study is to examine whether there are alternatives to the collecting of urine under the period of 24 hours in cases where the secretion of stone-forming substances is constant across days. The question is whether the excretion of stone-forming sub-stances can be estimated by relating the concentration of urine to the creatinine concentration of urine, since the excretion of creatinine is relatively constant over a day. If so, the concentration of stone-forming substances in urine could be relat-ed to the concentration of creatinine in urine in the same way as drug analyses commonly are. Method. The subjects collected a 24h collection of urine. The first urine portion was stored in a container, while all subsequent urine was collected in a separate container. After about a week, another timed collection of urine was performed, but this time only in one container. The 24 h solute excretions were compared to each other and to the solute creatinine index. Results. A strong cor-relation was found between the creatinine index of calcium and the 24 h excretion of calcium. A somewhat weaker correlation was found for magnesium and a lack of correlation for phosphate and potassium. Conclusion. Results indicate that creatinine indexes in general do not predict 24 h excretions. However, creatinine index appears to predict the excretion of calcium and, to some extent, magnesium.