Sevelamer hydrochloride in peritoneal dialysis patients: results of a multicenter cross-sectional study. (73/368)

BACKGROUND: Sevelamer hydrochloride is a phosphate binder widely employed in hemodialysis patients. Until now, information about its efficacy and safety in peritoneal dialysis patients has been scarce. PATIENTS AND METHODS: In September 2005 a cross-sectional study of demographic, biochemical, and therapeutic data of patients from 10 peritoneal dialysis units in Catalonia and the Balearic Islands, Spain, was conducted. RESULTS: We analyzed data from 228 patients. At the time of the study, 128 patients (56%) were receiving sevelamer. Patients receiving sevelamer were younger (p < 0.01), showed a longer period of time on dialysis (p < 0.01), and had a lower Charlson Comorbidity Index (p < 0.01). Serum calcium and intact parathyroid hormone levels were not different between the two groups, while phosphate levels <5.5 mg/dL were observed more frequently in patients not receiving sevelamer (79% vs 61%, p < 0.01). Serum total cholesterol (167 +/- 41 vs 189 +/- 42 mg/dL, p < 0.01) and low density lipoprotein (LDL) cholesterol (90 +/- 34 vs 109 +/- 34 mg/dL, p < 0.01), but not high density lipoprotein cholesterol or triglycerides, were lower in sevelamer-treated patients. Moreover, sevelamer-treated patients displayed a higher serum albumin (38 +/- 5 vs 36 +/- 4 g/L, p < 0.01) and a lower C-reactive protein (4.9 +/- 12.8 vs 8.8 +/- 15.7 mg/L, p < 0.01). Blood bicarbonate levels <22 mmol/L were observed more frequently in patients receiving sevelamer (22% vs 5%, p < 0.01). Logistic regression analysis adjusting by confounding variables confirmed that sevelamer therapy was associated with serum total cholesterol <200 mg/dL [relative risk (RR): 2.77, 95% confidence interval (CI): 1.44 - 5.26, p = 0.002] and blood bicarbonate <22 mmol/L (RR: 8.5, 95% CI: 2.6 - 27.0, p < 0.001), but not with serum phosphate >5.5 mg/dL, calcium-phosphate product >55 mg(2)/dL(2), serum albumin <35 g/L, or C-reactive protein >5 mg/L. CONCLUSIONS: This uncontrolled cross-sectional study in peritoneal dialysis patients showed that sevelamer hydrochloride treatment allows an adequate serum phosphate level in about 60% of patients and significantly reduces total and LDL-cholesterol levels. Since this treatment is associated with metabolic acidosis in 22% of patients, we recommend close monitoring of bicarbonate levels in this group of patients until the clinical significance of this result is clarified.  (+info)

Comparison of physical, chemical and cellular responses to nano- and micro-sized calcium silicate/poly(epsilon-caprolactone) bioactive composites. (74/368)

In this study, we fabricated nano-sized calcium silicate/poly(epsilon-caprolactone) composite (n-CPC) and micro-sized calcium silicate/poly(epsilon-caprolactone) composite (m-CPC). The composition, mechanical properties, hydrophilicity and degradability of both n-CPC and m-CPC were determined, and in vitro bioactivity was evaluated by investigating apatite forming on their surfaces in simulated body fluid (SBF). In addition, cell responses to the two kinds of composites were comparably investigated. The results indicated that n-CPC has superior hydrophilicity, compressive strength and elastic modulus properties compared with m-CPC. Both n-CPC and m-CPC exhibited good in vitro bioactivity, with different morphologies of apatite formation on their surfaces. The apatite layer on n-CPC was more homogeneous and compact than on m-CPC, due to the elevated levels of calcium and silicon concentrations in SBF from n-CPC throughout the 14-day soaking period. Significantly higher levels of attachment and proliferation of MG63 cells were observed on n-CPC than on m-CPC, and significantly higher levels of alkaline phosphatase activity were observed in human mesenchymal stem cells (hMSCs) on n-CPC than on m-CPC after 7 days. Scanning electron microscopy observations revealed that hMSCs were in intimate contact with both n-CPC and m-CPC surfaces, and significantly cell adhesion, spread and growth were observed on n-CPC and m-CPC. These results indicated that both n-CPC and m-CPC have the ability to support cell attachment, growth, proliferation and differentiation, and also yield good bioactivity and biocompatibility.  (+info)

Short-term treatment with sevelamer increases serum fetuin-a concentration and improves endothelial dysfunction in chronic kidney disease stage 4 patients. (75/368)

BACKGROUND AND OBJECTIVES: Vascular calcification and endothelial dysfunction contribute to the development of cardiovascular disease in patients with chronic kidney disease (CKD). Sevelamer, a non-calcium-based phosphate binder, has been shown to attenuate cardiovascular calcification in CKD patients, although the exact mechanism has not been clarified. This study was designed to investigate the effect of short-term sevelamer treatment on both serum fetuin-A concentrations and endothelial dysfunction seen in CKD patients. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Fifty nondiabetic stage 4 CKD patients whose phosphate levels were > or =5.5 mg/dl were enrolled in this 8-wk randomized prospective study. Thirty-six healthy volunteers served as matched controls. Patients were treated with either sevelamer (n = 25, 12 males) or calcium acetate (n = 25, 13 males). Fetuin-A, high-sensitivity C-reactive protein, Ca x PO4 product, flow-mediated dilation (FMD), insulin, and homeostasis model assessment (HOMA) were obtained at baseline and after the treatment period. RESULTS: As expected, CKD patients had significantly lower levels of fetuin-A and FMD, and significantly higher levels of intact parathyroid hormone, Ca x PO4 product, and high-sensitivity C-reactive protein than controls (P < 0.001 for all). The use of sevelamer led to a significant increase in the fetuin-A concentration with improvement in FMD, whereas no significant difference was observed in the calcium acetate group. In a multiple regression analysis, FMD levels were independently related to fetuin-A both before (beta = 0.63, P < 0.001) and after (beta = 0.38, P = 0.004) treatment. CONCLUSIONS: This small, randomized, prospective study shows that short-term sevelamer treatment significantly increases fetuin-A levels and improves FMD in nondiabetic stage 4 CKD patients.  (+info)

Endodontic treatment with MTA apical plugs: a case report. (76/368)

Apexification with calcium hydroxide is associated with certain difficulties, such as the very long treatment time required, the possibility of tooth fracture, and incomplete calcification of the bridge. Use of an apical plug is an alternative treatment for open apices, and this has gained popularity in recent years, employing mineral trioxide aggregate (MTA) for optimal results. Here we report the successful treatment of two maxillary central incisors that had open apices and periapical lesions using MTA apical plugs after the root canals had been debrided and rinsed with 2.5% NaOCl. Calcium hydroxide paste was then placed in the canals for 1 week, before the apical portion of the canals (5 mm) was filled with the MTA plug. The remaining portion of the root canal was then sealed with a post and crown. After 6 months of follow-up, the clinical and radiographic appearance of the teeth showed a decrease of the periapical lesions. At 2 years, although the left post had been lost and the periapical lesion of the left central incisor had subsequently deteriorated, the right central incisor had healed successfully. Considering the importance of a coronal seal, the use of MTA for apical plugging appears to be a valid option.  (+info)

Lactic acid production from lime-treated wheat straw by Bacillus coagulans: neutralization of acid by fed-batch addition of alkaline substrate. (77/368)

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High-calcium mineral water as a calcium supplementing measure for post-thyroidectomy hypocalcemia. (78/368)

AIM: The aim of this study was to test the possibility of enhancing blood calcium levels in totally thyroidectomized patients by supplementation with 1 L/d carbonate-bicarbonate-high-calcium mineral water. METHODS: This study enrolled 95 outpatients, totally thyroidectomized four months earlier, and hence treated with oral calcium and vitamin-D. At recruitment, ionized blood calcium was either below (Group A; N. 55) or above (Group B; N. 40, randomly divided in Group B1 [N. 20] and Group B2 [N.20]) the lower limit of the normal range (1.12 mmol/L). For one month, Group A was treated with 1 L/d high-calcium (483 mg/L) mineral water and continued the usual therapy with Ca and vitamin-D. In contrast, Group B1 and Group B2 substituted their Ca and vitamin-D therapy with 1 L/d high-calcium mineral water (Group B1) or 1 L/d of placebo mineral water (Ca:80 mg/L) (Group B2). RESULTS: After one month, a significant 7.5% increase in blood ionized-calcium levels was observed in Group A, no change in Group B1 and a significant drop below normality in Group B2 (Group B2 vs Group B1, P<0.001). Thereafter, 1 L/d of the high-calcium mineral water, given to Group B2 instead of placebo for an additional month, significantly enhanced ionized-calcium levels above the lower limit of normality (Group B2 vs Group B1, NS). CONCLUSION: These experiments show that calcium supplementation as 1 L/d of a high-calcium mineral water may efficaciously enhance blood calcium levels in thyroidectomized patients. This complementary treatment might at least in part contribute to the prevention and/or treatment of hypocalcemia and substitute vitamin-D and calcium therapies after thyroidectomy.  (+info)

Metaanalysis of filler materials in periapical surgery. (79/368)

OBJECTIVE: To evaluate the success and failure, apical sealing and biocompatibility of silver amalgam, IRM, SuperEBA and MTA as retrograde filler materials. STUDY DESIGN: A metaanalysis is made of filler materials in periapical surgery, evaluating a total of 30 articles published in recent years. RESULTS: Percentage success with silver amalgam was 76.5% and slightly inferior to that afforded by IRM. Performance in turn increased considerably when the materials used were SuperEBA or MTA. As regards marginal leakage, MTA with a mean leakage time of 65.5 days afforded the best results, followed by SuperEBA, IRM and silver amalgam. MTA was the most biocompatible of the materials studied, with practically no inflammatory response, while inflammation proved mild or moderate with SuperEBA, mild with IRM, and moderate to severe in the case of silver amalgam. Tissue regeneration was only observed with MTA, in the same way as cement appositioning. Bone neoformation was observed with all four filler materials. CONCLUSIONS: MTA appears to be an ideal material, though the results obtained require confirmation by in vivo studies.  (+info)

Cell toxicity, hemolytic action and clastogenic activity of asbestos and its substitutes. (80/368)

The cell toxicity, hemolytic and clastogenic activity were examined in various kinds of asbestos and some asbestos substitutes with reference to the their mineralogical and physicochemical characteristics. There were thirty-five fibrous and non-fibrous samples including UICC chrysotile, size-selected samples of UICC chrysotile, chrysotile altered by heating and grinding, Yamabe (Japan) chrysotile with long and short fibers, Coalinga (U.S. A.) chrysotile with short fibers, UICC crocidolite, amosite, and 19 non-asbestos samples such as, glass fibers, calcium silicates, sepiolites and some clay minerals. The cell toxicity and the hemolytic and clastogenic activity of asbestos were the strongest for chrysotile among all of the asbestos samples tested, and their strengths varied with fiber length and with the conditions of grinding and heating. These cellular effects of Yamabe chrysotile with long fibers and size-selected UICC chrysotile with long fibers were stronger than those of chrysotile of the same origin but with short fibers. These effects were weaker in chrysotile altered by heating and grinding. Among the asbestos substitutes, the cell toxicity, hemolytic and clastogenic activities of thin glass fibers were more marked than those of thick glass fibers. The four types of sepiolite were strongly hemolytic, but their cell toxicity and clastogenicity varied according to their grade of crystallinity and/or fiber size. These effects of calcium silicates and some clay minerals were generally low but varied with mineral species. In general, the cell toxicity, hemolytic and clastogenic activities of the asbestos substitutes tested here were mild compared with those of asbestos.  (+info)