PubMed Health⌕ Search

Biomedical subjects

F Akcicek

Publications and source records attributed to F Akcicek.

13 recordsLinked to original sources
PubMed2006

Severe vitamin D deficiency in chronic renal failure patients on peritoneal dialysis.

UNLABELLED: The aim of this study was to evaluate the prevalence of vitamin D deficiency in chronic renal failure (CRF) patients on peritoneal dialysis (PD) and to correlate the findings with various demographic and renal osteodystrophy markers. METHOD: This cross-sectional, multicenter study was carried out in 273 PD patients with a mean age of 61.7 +/- 10.9 years and mean duration of PD 3.3 +/- 2.2 years. It included 123 female and 150 male patients from 20 centers in Greece and Turkey, countries that are on the same latitude, namely, 36-42 degrees north. We measured 25(OH)D3 and 1.25(OH)2D3 levels and some other clinical and laboratory indices of bone mineral metabolism. RESULTS: Of these 273 patients 92% (251 patients) had vitamin D deficiency i.e. serum 25(OH)D3 levels less than 15 ng/ml, 119 (43.6%) had severe vitamin D deficiency i.e., serum 25(OH)D3 levels, less than 5 ng/ml, 132 (48.4%) had moderate vitamin D deficiency i.e., serum 25(OH)D3 levels, 5-15 ng/ml, 12 (4.4%) vitamin D insufficiency i.e., serum 25(OH)D3 levels 15 - 30 ng/ml and only 10 (3.6%) had adequate vitamin D stores. We found no correlation between 25(OH)D3 levels and PTH, serum albumin, bone alkaline phosphatase, P, and Ca x P. In multiple regression analyses, the independent predictors of 25(OH)D3 were age, presence of diabetes (DM-CRF), levels of serum calcium and serum 1.25(OH)2D3. CONCLUSION: We found a high prevalence (92%) of vitamin D deficiency in these 273 PD patients, nearly one half of whom had severe vitamin D deficiency. Vitamin D deficiency is more common in DM-CRF patients than in non-DM-CRF patients. Our findings suggest that these patients should be considered for vitamin D supplementation.

Adult↗
PubMed2001

How can we standardize peritoneal thickness measurements in experimental studies in rats?

OBJECTIVE: The various methods of measuring peritoneal thickness in experimental studies in rats have yielded conflicting results. Also, no standard method exists to assess histologic findings in peritoneal morphology. We therefore undertook the present study to create a reproducible and standard method for assessing rat peritoneal histology in experimental studies. METHODS: Parietal peritoneal samples from 61 Wistar albino rats were used in the study. Excepting the skin, the whole abdominal wall from each rat was cut two-dimensionally (longitudinally and horizontally), fixed in formalin, and processed routinely for light microscopy. Slides were divided into two groups according to the direction of the inner abdominal muscle fibers in the sections. Longitudinal and horizontal sections of abdominal muscle were evaluated. For every section, one histopathology image was captured from a light microscope to an IBM-compatible computer. Peritoneal thickness (mean of the maximum and the minimum) and submesothelial area (SMA) were drawn on the image. A computer program then automatically performed measurements. Two different measurement methods were compared, based on the same sections. RESULTS: The mean peritoneal thickness was 91 +/- 8 microm in the longitudinal sections and 75 +/- 7 microm in the horizontal sections (p < 0.05). Measurements of the SMA were found to be 47,762 +/- 4,374 microm2 for the longitudinal sections and 40,389 +/- 3,631 microm2 for the horizontal sections (p < 0.05). In both types of sections, a positive correlation (96% for longitudinal and 90% for horizontal) was found between the SMA and the peritoneal thickness (p < 0.01). The SMA measurements correlated significantly with functional properties [ratio of the dialysate concentration of glucose initially and after a 1-hour dwell (D1/D0 glucose), ultrafiltration, and protein loss; p < 0.01]. CONCLUSION: Peritoneal thickness can be measured as a mean of the minimum and maximum values. That measurement strongly correlates with submesothelial area. Both types of sections can be used, but the horizontal and longitudinal sections show systematic differences. All samples in a study should be taken using the same section pattern, either longitudinal or horizontal.

Animals↗
PubMed1997

The efficiency of fractionated parenteral iron treatment in CAPD patients.

Some chronic renal failure patients respond poorly to recombinant human erythropoietin (rHuEPO). In continuous ambulatory peritoneal dialysis (CAPD) patients, such a poor response may indicate inadequate dialysis or low body iron stores. To correct iron deficiency, once-a-week intravenous iron supplementation is recommended. However, hemodialysis patients receive iron supplements three times a week. This study was designed to compare the efficacy of iron supplementation between once-weekly and twice-weekly regimens. In both groups, rHuEPO doses were similar. Seventeen CAPD patients were studied. All had hemoglobin levels less than 10 g/dL. Ten patients were given 100 mg intravenous iron once weekly, and 7 were given 50 mg intravenous iron twice weekly until a total iron dose of 600 mg was achieved (stage I). The patients were crossed over to receive another 600 mg iron (stage II). Hematocrit increased significantly in patients receiving twice-a-week iron supplementation (+3.8% and 6%) compared to those receiving once-a-week iron supplementation (+1.3% and 1.4%) during stages I and II. The ferritin levels were not different between the groups. In conclusion, rHuEPO is more effective when administered with intravenous iron.

Adult↗
PubMed1992

Correlates of aldosterone-induced increases in Cai2+ and Isc suggest that Cai2+ is the second messenger for stimulation of apical membrane conductance.

Studies were performed on monolayers of cultured A6 cells, grown on permeable filters, to determine the second messenger system involved in the aldosterone-induced increase in electrogenic sodium transport. Addition of aldosterone (1 microM) to the solution bathing the basal surface of cells caused both an increase in Isc and threefold transient rise in intracellular calcium Cai2+ after a delay of approximately 60 min. Because both events were inhibited by actinomycin D and cyclohexamide, they appeared to require transcriptional and translational processes. Addition of BAPTA to the bathing media to chelate Cai2+ reduced Isc and the delayed Cai2+ transient; 50 microM BAPTA inhibited Isc and the rise in Cai2+ by greater than 80%. Further studies suggested that the action of aldosterone to increase Isc may be dependent on a calcium/calmodulin-dependent protein kinase, because W-7 and trifluoperazine reduced the aldosterone-induced Isc in a dose-dependent manner. Taken together, these observations suggest that calcium is a second messenger for the action of aldosterone on sodium transport, and suggest, for the first time, that agonists which bind to intracellular receptors can utilize, via delayed processes dependent on de novo transcription and translation, intracellular second messenger systems to regulate target cell function.

Aldosterone↗