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Öğe Cardiovascular phenotypes in children with CKD: The 4C study(American Society of Nephrology, 2017) Schaefer F.; Doyon A.; Azukaitis K.; Bayazit A.; Canpolat N.; Duzova A.; Niemirska A.; Sözeri B.; Thurn D.; Anarat A.; Ranchin B.; Litwin M.; Caliskan S.; Candan C.; Baskin E.; Yilmaz E.; Mir S.; Kirchner M.; Sander A.; Haffner D.; Melk A.; Wühl E.; Shroff R.; Querfeld U.; 4C Study ConsortiumBackground and objectives Cardiovascular disease is the most important comorbidity affecting long-term survival in children with CKD. Design, setting, participants, & measurements The Cardiovascular Comorbidity in Children with CKD Study is a multicenter, prospective, observational study in children ages 6–17 years old with initial GFR of 10–60 ml/min per 1.73 m2. The cardiovascular status is monitored annually, and subclinical cardiovascular disease is assessed by noninvasive measurements of surrogate markers, including the left ventricular mass index, carotid intima-media thickness, and central pulse wave velocity. We here report baseline data at study entry and an explorative analysis of variables associated with surrogate markers. Results A total of 737 patients were screened from October of 2009 to August of 2011 in 55 centers in 12 European countries, and baseline data were analyzed in 688 patients. Sixty-four percent had congenital anomalies of the kidney and urinary tract; 26.1% of children had uncontrolled hypertension (24-hour ambulatory BP monitoring; n=545), and the prevalence increased from 24.4% in CKD stage 3 to 47.4% in CKD stage 5. The prevalence of left ventricular hypertrophy was higher with each CKD stage, from 10.6% in CKD stage 3a to 48% in CKD stage 5. Carotid intima-media thickness was elevated in 41.6%, with only 10.8% of patients displaying measurements below the 50th percentile. Pulse wave velocity was increased in 20.1%. The office systolic BP SD score was the single independent factor significantly associated with all surrogate markers of cardiovascular disease. The intermediate end point score (derived from the number of surrogate marker measurements >95th percentile) was independently associated with a diagnosis of congenital anomalies of the kidney and urinary tract, time since diagnosis of CKD, body mass index, office systolic BP, serum phosphorus, and the hemoglobin level. Conclusions The baseline data of this large pediatric cohort show that surrogate markers for cardiovascular disease are closely associated with systolic hypertension and stage of CKD. © 2016 by the American Society of Nephrology.Öğe Dimensional and physical properties of various single pique fabrics(1999) Bayazit A.The physical and dimensional properties of various single pique fabrics knitted with OE-Rotor cotton yarns were researched and the results examined statistically. The results were also compared with those from single jersey fabrics. Differences in physical properties such as air permeability, abrasion resistance and mass per unit area are noted.Öğe Dimensional characteristics of different jacquard [Die Formeigenschaften verschiedener Jacquardmuster](2001) Bayazit A.; Donmez S.A research project has been carried out at Ege University, Turkey, to evaluate the dimensional characteristics of two-colour jacquard fabrics having different tension values and made from acrylic yam. Two different patterns were used on the front of the knitted fabric. The reverse was worked as single-jersey, float-stick jacquard or double-jersey with a striped, filet or twice reverse side. It was found that, with an increasing tension, the total yam length per carriage pass decreased. The least yam was used when working the floot jacquard pattern, and the most yam was used when producing the striped reverse side. The yam consumption when working jacquard patterns having first and twice reverse sides was more or less the same. An increase in tension and relaxation led to a reduction in the course density. With reduced tension or an increased degree of relaxation, the wale density value increased.Öğe The dimensional properties of various jacquard structures(2002) Bayazit A.; Donmez S.The dimensional properties of two-coloured jacquard structures knitted in various tightnesses were investigated statistically. Two different jacquard patterns were used at the front of the fabric. The reverse side was knitted in single-jersey miss jacquard, double-jersey horizontally striped, vertically striped and birds eye jacquard structures. In addition, there are tubular reverse side and ladder reverse side jacquard structures - all are explained. New arrangements or combinations of these basic structures can produce new jacquard forms. Previous research by Bauer (1993), Brackenbury, Fahmy (1976) and Fahmy and Newton (1976) is noted. The machinery and experimental knitting procedures are described. Dry and wash relaxation processes were incorporated. Measurements taken from the samples included length of yarn in a course (L), course-spacing © and wale-spacing (w) and these are amplified. The resulting relationships of tightness/progress of relaxation and the measurements taken are discussed and the yarn amounts used.Öğe Genetic, environmental, and disease-associated correlates of vitamin D status in children with CKD(American Society of Nephrology, 2016) Doyon A.; Schmiedchen B.; Sander A.; Bayazit A.; Duzova A.; Canpolat N.; Thurn D.; Azukaitis K.; Anarat A.; Bacchetta J.; Mir S.; Shroff R.; Yilmaz E.; Candan C.; Kemper M.; Fischbach M.; Cortina G.; Klaus G.; Wuttke M.; Köttgen A.; Melk A.; Querfeld U.; Schaefer F.; 4C Study ConsortiumBackground and objectives: Vitamin D deficiency is endemic in children with CKD.We sought to investigate the association of genetic disposition, environmental factors, vitamin D supplementation, and renal function on vitamin D status in children with CKD. Design, setting, participants, & measurements Serum: 25-hydroxy-vitamin D, 1,25-dihydroxy-vitamin D, and 24,25-dihydroxy-vitamin D concentrations were measured cross-sectionally in 500 children from 12 European countries with CKD stages 3-5. All patients were participants of the Cardiovascular Comorbidity in Children with Chronic Kidney Disease Study, had CKD stage 3-5, and were age 6-18 years old. Patients were genotyped for single-nucleotide polymorphisms in the genes encoding 25-hydroxylase, vitamin D binding protein, 7-dehydrocholesterol reductase, and 24-hydroxylase. Associations of genetic status, season, local solar radiation, oral vitamin D supplementation, and disease-associated factors with vitamin D status were assessed. Results: Two thirds of patientswere vitamin D deficient (25-hydroxy-vitamin D<16 ng/ml). 25-Hydroxy-vitamin D concentrations varied with season and were twofold higher in vitamin D-supplemented patients (21.6 [14.1] versus 10.4 [10.1] ng/ml; P<0.001). Glomerulopathy, albuminuria, and girls were associated with lower 25-hydroxy-vitamin D levels. 24,25-dihydroxy-vitamin D levels were closely correlated with 25-hydroxy-vitamin D and 1,25-dihydroxy-vitamin D (r=0.87 and r=0.55; both P<0.001). 24,25-dihydroxy-vitamin D concentrations were higher with higher c-terminal fibroblast growth factor 23 and inversely correlated with intact parathyroid hormone. Whereas 25-hydroxy-vitamin D levels were independent of renal function, 24,25-dihydroxy-vitamin D levels were lower with lower eGFR. Vitamin D deficiency was more prevalent in Turkey than in other European regions independent of supplementation status and disease-related factors. Single-nucleotide polymorphisms in the vitamin D binding protein genewere independently associated with lower 25-hydroxy-vitamin Dand higher 24,25-dihydroxy-vitamin D. Conclusions: Disease-related factors and vitamin D supplementation are the main correlates of vitamin D status in children with CKD. Variants in the vitamin D binding protein showedweak associations with the vitamin D status. © 2016 by the American Society of Nephrology.Öğe Indoxyl sulfate associates with cardiovascular phenotype in children with chronic kidney disease(Springer Verlag, 2019) Holle J.; Querfeld U.; Kirchner M.; Anninos A.; Okun J.; Thurn-Valsassina D.; Bayazit A.; Niemirska A.; Canpolat N.; Bulut I.K.; Duzova A.; Anarat A.; Shroff R.; Bilginer Y.; Caliskan S.; Candan C.; Harambat J.; Özcakar Z.B.; Soylemezoglu O.; Tschumi S.; Habbig S.; Yilmaz E.; Balat A.; Zurowska A.; Cakar N.; Kranz B.; Ertan P.; Melk A.; Azukaitis K.; Schaefer F.Background: Cardiovascular disease is the leading cause of death in children with chronic kidney disease (CKD). Serum levels of gut-derived uremic toxins increase with deterioration of kidney function and are associated with cardiac comorbidities in adult CKD patients. Methods: Indoxyl sulfate (IS) and p-cresyl sulfate (pCS) were measured by high-performance liquid chromatography in serum of children participating in the Cardiovascular Comorbidity in Children with CKD (4C) Study. Results were correlated with measurements of the carotid intima-media thickness (cIMT), central pulse wave velocity (PWV), and left ventricular mass index (LVMI) in children aged 6–17 years with initial eGFR of 10–60 ml/min per 1.73 m2. Results: The median serum levels of total IS and of pCS, measured in 609 patients, were 5.3 µmol/l (8.7) and 17.0 µmol/l (21.6), respectively. In a multivariable regression model, IS and pCS showed significant positive associations with urea and negative associations with eGFR and uric acid. Furthermore, positive associations of pCS with age, serum albumin, and non-Mediterranean residency and a negative association with glomerular disease were observed. By multivariable regression analysis, only IS was significantly associated with a higher cIMT SDS at baseline and progression of PWV SDS within 12 months, independent of other risk factors. Conclusions: Serum levels of gut-derived uremic toxins IS and pCS correlated inversely with eGFR in children. Only IS was significantly associated with surrogate markers of cardiovascular disease in this large pediatric CKD cohort. © 2019, IPNA.
