Estimation of the glomerular filtration rate - comparison between serum creatinine, cystatin C and calculated creatinine clearance

Izhodišča V želji po zgodnejšem odkrivanju in zdravljenju kronične ledvične bolezni (KLB) je ocena glomerulne filtracije (GF) pridobila na pomenu. Za oceno GF najpogosteje uporabljamo serumsko koncentracijo kreatinina, v zadnjem času tudi cistatina C ter Cockcroft-Gaultovo (C&G) enačbo in enačbo MDRD (Modification of Diet in Renal Disease) raziskave za izračun očistka kreatinina. V naši preiskavi smo med seboj primerjali različne označevalce GF glede na zlati standard, očistek [zgoraj]51CrEDTA. Bolniki in metode Vključili smo 468 bolnikov s stopnjo 2 do 5 KLB (216 žensk in 252 moškihpovprečna starost 60,4 +/- 14,3 leta), ki so imeli določen očistek [zgoraj] 51CrEDTA. Ob odvzemu krvi za določitev očistka [zgoraj]51CrEDTA smo izmerili serumsko koncentracijo kreatinina in cistatina C ter na podlagi C&G enačbe in enačbe MDRD raziskave izračunali kreatininski očistek. Rezultati Ugotovili smo povezavo med očistkom [zgoraj]CrEDTA in serumsko koncentracijo kreatinina (r=-0,889), recipročno vrednostjo serumskega kreatinina (r=0,866), serumsko koncentracijo cistatina C (r=-0,902), recipročno vrednostjo cistatina C (r=0,901) in očistkom kreatinina, izračunanega tako po enačbi C&G (r=0,808) kot po enačbi raziskave MDRD (r=0,901). Ugotovili smo (ROC krivulje) višjo diagnostično zanesljivost meritev serumskega cistatina C v primerjavi z diagnostično zanesljivostjo meritev serumskega kreatinina (P=0,006) in očistka kreatinina, izračunanega po enačbi C&G (P=0,004) pri mejni vrednosti GF 60 ml/min/1,73m[na]2. Diagnostična zanesljivost serumskega cistatina C je bila v primerjavi z diagnostično zanesljivostjo enačbe raziskave MDRD statistično neznačilna. Zaključki Serumski cistatin C je v primerjavi s serumskim kreatininom in izračunom očistka kreatinina z enačbo C&G boljša metoda za oceno GF. Izračun očistka kreatinina z enačbo raziskave MDRD se je izkazal kot diagnostično enako zanesljiv kot metoda določanja cistatina C.Background With increasing emphasis on the earlier detection and management of chronic kidney disease (CKD), estimation of the glomerular filtration rate (GFR) has assumed greater importance. GFR is often estimated from serum creatinine, recently also from serum cystatin C and by Cockcroft-Gault (C&G) and Modification of diet in renal disease (MDRD) formulas. In our study different markers of GFR were compared with gold standard [above]51CrEDTA clearance. Patients and methods We included 468 patients with CKD stages 2-5 (216 women and 252 men, average age 60.4 +/- 14.3 years), who performed [above]51CrEDTA clearance. In each patient, serum creatinine and cystatin C were determined, creatinine clearance was calculated using C&G and MDRD formulas. Results We found significant correlation between [above]51CrEDTA clearance with serum creatinine (r=-0,889), reciprocal of serum creatinine (r=0.866), serum cystatin C (r=-0.902), reiprocal of serum cystatin C (r=0.901) and with calculated creatinine clearance from C&G (r=0.808) and MDRD formulas (r=0.901). The ROC curve analysis (cut-off for GFR 60 ml/min/1.73 m[sup]2) showed that serum cystatin C had higher diagnostic accuracy than serum creatinine (P=0.006) and calculated creatinine clearance from C&G formula (P=0.004). No difference and diagnostic accuract was found between serum cystatin C and creatinine clearance calculated from MDRD formula. Conclusions serum cystatin C is a better marker of GFR and has a higher diagnostic accuracy than serum creatinine and calculated creatinine clearance from C&G formula. No difference in diagnostic accuracy was found between serum cystatin C and creatinine clearance calculated from the MDRD formula

Effect of hydrolyzable tannins on glucose-transporter expression and their bioavailability in pig small-intestinal 3D cell model

Intestinal transepithelial transport of glucose is mediated by glucose transporters, and affects postprandial blood-glucose levels. This study investigates the effect of wood extracts rich in hydrolyzable tannins (HTs) that originated from sweet chestnut (Castanea sativa Mill.) and oak (Quercus petraea) on the expression of glucose transporter genes and the uptake of glucose and HT constituents in a 3D porcine-small-intestine epithelial-cell model. The viability of epithelial cells CLAB and PSI exposed to different HTs was determined using alamarBlue^®. qPCR was used to analyze the gene expression of SGLT1, GLUT2, GLUT4, and POLR2A. Glucose uptake was confirmed by assay, and LC–MS/ MS was used for the analysis of HT bioavailability. HTs at 37 µg/mL were found to adversely affect cell viability and downregulate POLR2A expression. HT from wood extract Tanex at concentrations of 4 µg/mL upregulated the expression of GLUT2, as well as glucose uptake at 1 µg/mL. The time-dependent passage of gallic acid through enterocytes was influenced by all wood extracts compared to gallic acid itself as a control. These results suggest that HTs could modulate glucose uptake and gallic acid passage in the 3D cell model

Simple Cystatin C Formula for Estimation of Glomerular Filtration Rate in Overweight Patients with Diabetes Mellitus Type 2 and Chronic Kidney Disease

In clinical practice the glomerular filtration rate (GFR) is estimated from serum creatinine-based equations like the Cockcroft-Gault formula (C&G) and Modification of Diet in Renal Disease formula (MDRD). Recently, serum cystatin C-based equations, the newer creatinine formula (The Chronic Kidney Disease Epidemiology Collaboration formula (CKD-EPI)), and equation that use both serum creatinine and cystatin C (CKD-EPI creatinine & cystatin formula) were proposed as new GFR markers. Present study compares serum creatinine-based equations, combined (including both serum creatinine and cystatin C) equation, and serum simple cystatin C formula (100/serum cystatin C) against 51CrEDTA clearance in 113 adult overweight Caucasians with diabetes mellitus type 2 (DM2) and chronic kidney disease (CKD). The results of present study demonstrated that the simple cystatin C formula could be a useful tool for the evaluation of renal function in overweight patients with DM2 and impaired kidney function in daily clinical practice in hospital and especially in outpatients. Despite the advantages of the simple cystatin C formula, cystatin C-based equations cannot completely replace the “gold standard” for estimation of the GFR in a population of DM2 patients with CKD, but may contribute to a more accurate selection of patients requiring such invasive and costly procedures

Erythropoietic protoporphyria patients in Slovenia

Background: There are only scarce epidemiological data on the prevalence of erythropoietic protoporphyria (EPP) in a given population. The aim of this study was to assess the prevalence of EPP within the Slovenian population. Materials and methods: The patients were selected by routine examination of photosensitive patients and by studying hospital records. A quantitative method was used to assess protoporphyrin, with values larger than 530 nm/l considered elevated. Results: 32 EPP patients were detected, which allows us to estimate the prevalence of EPP in Slovenia at 1.75 per 100,000 inhabitants

New biomarkers and monitoring intracellular signaling pathways in autoimmune diseases

Izhodišča: Avtoimunske in kronične vnetne bolezni se še vedno pogosto zdravijo le z nespecifično imunosupresijo, ki ne prinaša ozdravitve. Spoznanje, da so citokini TNF in IFN-alfa bistveni v patogenezi bolezni, kot sta revmatoidni artritis in sistemski lupus eritematozus, pomeni napredek v razumevanju avtoimunskih bolezni. Znotrajcelične signalne poti, ki se aktivirajo kot odgovor na te klinično pomembne citokine, prenašajo signale s kinazno fosforilacijo proteinov in so bistvene za delovanje celic imunskega sistema. Malo je znanega o spremembah teh signalnih poti pri avtoimunskih boleznih. Nedavne klinične raziskave so pokazale, da se spoznanja iz živalskih modelov ne morejo neposredno prenesti na človeka. Za spremljanje aktivnosti bolezni in napoved odziva na novejše zdravljenje je potrebno razviti nova orodja za spremljanje humanega imunskega odziva. Obetajoče orodje v prihodnosti so novo odkriti biomarkerji. Še več si obetamo od pristopov, ki temeljijo na spremljanju signalnih poti na celični ravni. Zaključki: Razviti so bili biokemični analizni sistemi, ki temeljijo na pretočni citometriji in omogočajo profiliranje kinaz in fosfoproteinov na ravni posameznih celic. To bo omogočilo študije signalnih poti pri avtoimunskih in kroničnih vnetnih boleznih, saj so analizni sistemi prilagojeni prav celicam imunskega sistema, npr. v periferni krvi. Prvi rezultati kažejo značilne fosfo-signature citokinov (interferonov) v imunskih celicah bolnikov s SLE. Možnost spremljanja signalnih poti na celični ravni lahko prinese razvoj novih diagnostičnih možnosti, predvsem za spremljanje aktivnosti bolezni in vodenja zdravljenja. Rezultati študij pa lahko nakažejo tudi nove tarče, bolj specifičnega in manj toksičnega, zdravljenja z inhibitorji kinaz.Background: Almost all current therapeutic concepts in many autoimmune and chronic inflammatory diseases are based on the systemic suppression of immune functions and are not curative. Identification of cytokines TNF and IFN-alpha as major factors in the pathogenesis of diseases such as rheumatoid arthritis and systemic lupus erythematosus (SLE) represent a substantial improvement in understanding of autoimmune diseases. Intracellular signalling pathways that are activated in response to those clinically relevant cytokines, mediate signals through kinase phosphorylation of proteins and are at the core of immune cell function. However, little is known about their changes in autoimmune disease states. Recent trials emphasized the importance of directl yassessing the human immune responses, and that not all of what we learn for example in the mouse can be directly translated to humans. Thus, there is a need for the development of tools and assays to directly assess the human immune system, and to predict its responses to novel therapeutic entities. Newly discovered biomarkers represent promising tools. Even more promising are approaches, that are based on monitoring immune signaling on the single cell level. Conclusions: A series of assay systems for flow cytometric-based biochemical analysis at the single-cell level for kinase and phosphoprotein profiling have been developed. This will give us opportunity to study signal pathways also in autoimmune and chronic inflammatory diseases, as the analysing systems are adapted to immunocytes for example in peripheral blood. First results show characteristic phospho-signature of cytokines (interferons) in immune cells from SLE patients. Monitoring signaling pathways on the single cell level can lead to developments in new diagnostic tools, especially in monitoring of disease activity. Results can also identify new targets of more specific and less toxic therapy with kinase inhibitors

Uporabnost merjenja koncentracije estradiola in progesterona v folikularni tekočini pri napovedovanju izida IVF/ICSI postopka v naravnem ciklusu

Namen: Namen raziskave je bil ugotoviti ali lahko na osnovi koncentracije estradiola (E2) in progesterona (P) ter njunega razmerja v folikularni tekočini predvidimo izhod IVF/ICSI postopkov v naravnih ciklusih. Metode: V raziskavo smo vključili 91 žensk, pri katerih smo naredili 150 postopkov IVF/ICSI (78 IVF in 72 ICSI) v naravnem ciklusu. Folikularno tekočino smo zbrali pri aspiraciji foliklov. S t-testom testom smo primerjali koncentracije E2 in P v folikularni tekočini (FT) in njuno razmerje (FT P/FT E2) med ciklusi z uspešno (z jajčno celico) in ciklusi z neuspešno (brez jajčne celice) aspiracijo foliklov, med ciklusi z oploditvijo in ciklusi brez oploditve jajčne celice in med ciklusi z zanositvijo in ciklusi brez zanositve. Rezultati: Jajčno celico smo dobili v 123 (86,7 %) ciklusih, do oploditve je prišlo v 84 (68,3 %) in zanositve v 21 ciklusih (delež zanositve na ciklus 14,0 %). Povprečna koncentracija E2 v FT je bila 3530 +/- 1339 nmol/L, povprečna koncentracija P v FT 20649 +/- 9489 nmol/L in povprečna vrednost razmerja FT P/FT E2 7,18 +/- 6,42. Povprečne vrednost E2, P in njunega razmerja v FT se niso statistično pomembno razlikovale med ciklusi z uspešno in neuspešno aspiracijo jajčnih foliklov, med ciklusi z in brez oploditve jajčne celice in med ciklusi z in brez zanositve. Zaključek: Na osnovi vrednosti E2 in P v folikularni tekočini ne moremo predvideti uspešnosti postopkov IVF/ICSI v naravnem ciklusu.Purpose: The aim of the study was to establish whether follicular fluid (FF) estradiol (E2) and progesterone (P) measurement could be used to predict the outcome of unstimulated IVF/ICSI cycles. Methods: 91 women underwent 150 unstimulated IVF/ICSI cycles (78 IVF and 72 ICSI). Follicular fluid samples were collected at the time of oocyte recovery. Using the ttest, FF E2 and FF P levels and their ratios (FF P/FF E2) were compared between cycles with successful (with oocyte) and unsuccessful (without oocyte) oocyte recovery, between cycles with and without fertilization and between nonconception and conception cycles. Results: The oocyte recovery rate was 86.7% (123/150), the fertilization rate 68.3% (84/123) and the pregnancy rate per oocyte recovery 14.0% (21/150). The average FF E2 level was 3530 +/- 1339 nmol/L, average FF P 20649 +/- 9489 nmol/Land average FF P/FF E2 ratio 7.18 +/- 6.42. There were no statistically significant differences in FF E2, FF P levels and their ratio between cycles with unsuccessful and successful oocyte recovery, between cycles without and with fertilization, and between nonconception and conception cycles. Conclusion: From the FF E2 and P levels and their ratio, it is not possible to make inferences to the likelihood of oocyte recovery, fertilization and conception in unstimulated IVF/ICSI cycles