990 resultados para Mineral treatment
Resumo:
BACKGROUND Regenerative periodontal surgery using the combination of enamel matrix derivative (EMD) and natural bone mineral (NBM) with and without addition of platelet-rich plasma (PRP) has been shown to result in substantial clinical improvements, but the long-term effects of this combination are unknown. METHODS The goal of this study was to evaluate the long-term (5-year) outcomes after regenerative surgery of deep intrabony defects with either EMD + NBM + PRP or EMD + NBM. Twenty-four patients were included. In each patient, one intrabony defect was randomly treated with either EMD + NBM + PRP or EMD + NBM. Clinical parameters were evaluated at baseline and 1 and 5 years after treatment. The primary outcome variable was clinical attachment level (CAL). RESULTS The sites treated with EMD + NBM + PRP demonstrated a mean CAL change from 10.5 ± 1.6 to 6.0 ± 1.7 mm (P <0.001) at 1 year and 6.2 ± 1.5 mm (P <0.001) at 5 years. EMD + NBM-treated defects showed a mean CAL change from 10.6 ± 1.7 to 6.1 ± 1.5 mm (P <0.001) at 1 year and 6.3 ± 1.4 mm (P <0.001) at 5 years. At 1 year, a CAL gain of ≥4 mm was measured in 83% (10 of 12) of the defects treated with EMD + NBM + PRP and in 100% (all 12) of the defects treated with EMD + NBM. Compared to baseline, in both groups at 5 years, a CAL gain of ≥4 mm was measured in 75% (nine of 12 in each group) of the defects. Four sites in the EMD + PRP + NBM group lost 1 mm of the CAL gained at 1 year. In the EMD + NBM group, one defect lost 2 mm and four other defects lost 1 mm of the CAL gained at 1 year. No statistically significant differences in any of the investigated parameters were observed between the two groups. CONCLUSIONS Within their limits, the present results indicate that: 1) the clinical outcomes obtained with both treatments can be maintained up to a period of 5 years; and 2) the use of PRP does not appear to improve the results obtained with EMD + NBM.
Resumo:
The purpose of the study is to determine the effects of the BIG 1-98 treatments on bone mineral density. BIG 1-98 compared 5-year adjuvant hormone therapy in postmenopausal women allocated to four groups: tamoxifen (T); letrozole (L); 2-years T, 3-years L (TL); and 2-years L, 3-years T (LT). Bone mineral density T-score was measured prospectively annually by dual energy X-ray absorption in 424 patients enrolled in a sub-study after 3 (n = 150), 4 (n = 200), and 5 years (n = 74) from randomization, and 1 year after treatment cessation. Prevalence of osteoporosis and the association of C-telopeptide, osteocalcin, and bone alkaline phosphatase with T-scores were assessed. At 3 years, T had the highest and TL the lowest T-score. All arms except for LT showed a decline up to 5 years, with TL exhibiting the greatest. At 5 years, there were significant differences on lumbar T-score only between T and TL, whereas for femur T-score, differences were significant for T versus L or TL, and L versus LT. The 5-year prevalence of spine and femur osteoporosis was the highest on TL (14.5 %, 7.1 %) then L (4.3 %, 5.1 %), LT (4.2 %, 1.4 %) and T (4 %, 0). C-telopeptide and osteocalcin were significantly associated with T-scores. While adjuvant L increases bone mineral density loss compared with T, the sequence LT has an acceptable bone safety profile. C-telopeptide and osteocalcin are useful markers of bone density that may be used to monitor bone health during treatment. The sequence LT may be a valid treatment option in patients with low and intermediate risk of recurrence.
Resumo:
Context: In virologically suppressed, antiretroviral-treated patients, the effect of switching to tenofovir (TDF) on bone biomarkers compared to patients remaining on stable antiretroviral therapy is unknown. Methods: We examined bone biomarkers (osteocalcin [OC], procollagen type 1 amino-terminal propeptide, and C-terminal cross-linking telopeptide of type 1 collagen) and bone mineral density (BMD) over 48 weeks in virologically suppressed patients (HIV RNA < 50 copies/ml) randomized to switch to TDF/emtricitabine (FTC) or remain on first-line zidovudine (AZT)/lamivudine (3TC). PTH was also measured. Between-group differences in bone biomarkers and associations between change in bone biomarkers and BMD measures were assessed by Student's t tests, Pearson correlation, and multivariable linear regression, respectively. All data are expressed as mean (SD), unless otherwise specified. Results: Of 53 subjects (aged 46.0 y; 84.9% male; 75.5% Caucasian), 29 switched to TDF/FTC. There were reductions in total hip and lumbar spine BMD in those switching to TDF/FTC (total hip, TDF/FTC, −1.73 (2.76)% vs AZT/3TC, −0.39 (2.41)%; between-group P = .07; lumbar spine, TDF/FTC, −1.50 (3.49)% vs AZT/3TC, +0.25 (2.82)%; between-group P = .06), but they did not reach statistical significance. Greater declines in lumbar spine BMD correlated with greater increases in OC (r = −0.28; P = .05). The effect of TDF/FTC on bone biomarkers remained significant when adjusted for baseline biomarker levels, gender, and ethnicity. There was no difference in change in PTH levels over 48 weeks between treatment groups (between-group P = .23). All biomarkers increased significantly from weeks 0 to 48 in the switch group, with no significant change in those remaining on AZT/3TC (between-group, all biomarkers, P < .0001). Conclusion: A switch to TDF/FTC compared to remaining on a stable regimen is associated with increases in bone turnover that correlate with reductions in BMD, suggesting that TDF exposure directly affects bone metabolism in vivo.
Resumo:
The trabecular bone score (TBS) is an index of bone microarchitectural texture calculated from anteroposterior dual-energy X-ray absorptiometry (DXA) scans of the lumbar spine (LS) that predicts fracture risk, independent of bone mineral density (BMD). The aim of this study was to compare the effects of yearly intravenous zoledronate (ZOL) versus placebo (PLB) on LS BMD and TBS in postmenopausal women with osteoporosis. Changes in TBS were assessed in the subset of 107 patients recruited at the Department of Osteoporosis of the University Hospital of Berne, Switzerland, who were included in the HORIZON trial. All subjects received adequate calcium and vitamin D3. In these patients randomly assigned to either ZOL (n = 54) or PLB (n = 53) for 3 years, BMD was measured by DXA and TBS assessed by TBS iNsight (v1.9) at baseline and 6, 12, 24, and 36 months after treatment initiation. Baseline characteristics (mean ± SD) were similar between groups in terms of age, 76.8 ± 5.0 years; body mass index (BMI), 24.5 ± 3.6 kg/m(2) ; TBS, 1.178 ± 0.1 but for LS T-score (ZOL-2.9 ± 1.5 versus PLB-2.1 ± 1.5). Changes in LS BMD were significantly greater with ZOL than with PLB at all time points (p < 0.0001 for all), reaching +9.58% versus +1.38% at month 36. Change in TBS was significantly greater with ZOL than with PLB as of month 24, reaching +1.41 versus-0.49% at month 36; p = 0.031, respectively. LS BMD and TBS were weakly correlated (r = 0.20) and there were no correlations between changes in BMD and TBS from baseline at any visit. In postmenopausal women with osteoporosis, once-yearly intravenous ZOL therapy significantly increased LS BMD relative to PLB over 3 years and TBS as of 2 years.
Resumo:
BACKGROUND: Influence of genetic variants in the NOD2 gene may play a more important role in disease activity, behaviour and treatment of pediatric- than adult-onset Crohn's disease (CD). METHODS: 85 pediatric- and 117 adult-onset CD patients were tested for the three main NOD2 CD-associated variants (p.R702W, p.G908R and p.10007fs) and clinical data of at least two years of follow-up were compared regarding disease behaviour and activity, response to therapy and bone mineral density (BMD). RESULTS: Chronic active and moderate to severe course of CD is associated in patients with pediatric-onset (p=0.0001) and NOD2 variant alleles (p=0.0001). In pediatric-onset CD the average PCDAI-Score was significantly higher in patients carrying NOD2 variants (p=0.0008). In addition, underweight during course of the disease (p=0.012) was associated with NOD2 variants. Interestingly, osteoporosis was found more frequently in patients carrying NOD2 variant alleles (p=0.033), especially in pediatric-onset CD patients with homozygous NOD2 variants (p=0.037). Accordingly, low BMD in pediatric-onset CD is associated with a higher PCDAI (p=0.0092), chronic active disease (p=0.0148), underweight at diagnosis (p=0.0271) and during follow-up (p=0.0109). Furthermore, pediatric-onset CD patients with NOD2 variants are more frequently steroid-dependent or refractory (p=0.048) and need long-term immunosuppressive therapy (p=0.0213). CONCLUSIONS: These data suggests that the presence of any of the main NOD2 variants in CD is associated with osteoporosis and an age of onset dependent influence towards underweight, higher disease activity and a more intensive immunosuppressive therapy. This observation supports the idea for an early intensive treatment strategy in children and adolescent CD patients with NOD2 gene variants.
Resumo:
BACKGROUND The purpose of this study is to compare clinical outcomes in the treatment of deep non-contained intrabony defects (i.e., with ≥70% 1-wall component and a residual 2- to 3-wall component in the most apical part) using deproteinized bovine bone mineral (DBBM) combined with either enamel matrix protein derivative (EMD) or collagen membrane (CM). METHODS Forty patients with multiple intrabony defects were enrolled. Only one non-contained defect per patient with an intrabony depth ≥3 mm located in the interproximal area of single- and multirooted teeth was randomly assigned to the treatment with either EMD + DBBM (test: n = 20) or CM + DBBM (control: n = 20). At baseline and after 12 months, clinical parameters including probing depth (PD) and clinical attachment level (CAL) were recorded. The primary outcome variable was the change in CAL between baseline and 12 months. RESULTS At baseline, the intrabony component of the defects amounted to 6.1 ± 1.9 mm for EMD + DBBM and 6.0 ± 1.9 mm for CM + DBBM sites (P = 0.81). The mean CAL gain at sites treated with EMD + DBBM was not statistically significantly different (P = 0.82) compared with CM + DBBM (3.8 ± 1.5 versus 3.7 ± 1.2 mm). No statistically significant difference (P = 0.62) was observed comparing the frequency of CAL gain ≥4 mm between EMD + DBBM (60%) and CM + DBBM (50%) or comparing the frequency of residual PD ≥6 mm between EMD + DBBM (5%) and CM + DBBM (15%) (P = 0.21). CONCLUSION Within the limitations of the present study, regenerative therapy using either EMD + DBBM or CM + DBBM yielded comparable clinical outcomes in deep non-contained intrabony defects after 12 months.
Resumo:
AIM To assess the clinical and radiographic outcomes applying a combined resective and regenerative approach in the treatment of peri-implantitis. MATERIALS AND METHODS Subjects with implants diagnosed with peri-implantitis (i.e., pocket probing depth (PPD) ≥5 mm with concomitant bleeding on probing (BoP) and ≥2 mm of marginal bone loss or exposure of ≥1 implant thread) were treated by means of a combined approach including the application of a deproteinized bovine bone mineral and a collagen membrane in the intrabony and implantoplasty in the suprabony component of the peri-implant lesion, respectively. The soft tissues were apically repositioned allowing for a non-submerged healing. Clinical and radiographic parameters were evaluated at baseline and 12 months after treatment. RESULTS Eleven subjects with 11 implants were treated and completed the 12-month follow-up. No implant was lost yielding a 100% survival rate. At baseline, the mean PPD and mean clinical attachment level (CAL) were 8.1 ± 1.8 mm and 9.7 ± 2.5 mm, respectively. After 1 year, a mean PPD of 4.0 ± 1.3 mm and a mean CAL of 6.7 ± 2.5 mm were assessed. The differences between the baseline and the follow-up examinations were statistically significant (P = 0.001). The mucosal recession increased from 1.7 ± 1.5 at baseline to 3.0 ± 1.8 mm at the 12-month follow-up (P = 0.003). The mean% of sites with BoP+ around the selected implants decreased from 19.7 ± 40.1 at baseline to 6.1 ± 24.0 after 12 months (P = 0.032). The radiographic marginal bone level decreased from 8.0 ± 3.7 mm at baseline to 5.2 ± 2.2 mm at the 12-month follow-up (P = 0.000001). The radiographic fill of the intrabony component of the defect amounted to 93.3 ± 13.0%. CONCLUSION Within the limits of this study, a combined regenerative and resective approach for the treatment of peri-implant defects yielded positive outcomes in terms of PPD reduction and radiographic defect fill after 12 months.
Resumo:
While bisphosphonates reduce fracture risk over 3 to 5 years, the optimal duration of treatment is uncertain. In a randomized extension study (E1) of the Health Outcomes and Reduced Incidence with Zoledronic Acid Once Yearly - Pivotal Fracture Trial (HORIZON-PFT), zoledronic acid (ZOL) 5 mg annually for 6 years showed maintenance of bone mineral density (BMD), decrease in morphometric vertebral fractures, and a modest reduction in bone turnover markers (BTMs) compared with discontinuation after 3 years. To investigate the longer-term efficacy and safety of ZOL, a second extension (E2) was conducted to 9 years in which women on ZOL for 6 years in E1 were randomized to either ZOL (Z9) or placebo (Z6P3) for 3 additional years. In this multicenter, randomized, double-blind study, 190 women were randomized to Z9 (n=95) and Z6P3 (n=95). The primary endpoint was change in total hip BMD at year 9 vs. year 6 in Z9 compared with Z6P3. Other secondary endpoints included fractures, BTMs, and safety. From year 6 to 9, the mean change in total hip BMD was -0.54% in Z9 vs. -1.31% in Z6P3 (difference 0.78%; 95% confidence interval [CI]: -0.37%, 1.93%; p=0.183). BTMs showed small, non-significant increases in those who discontinued after 6 years compared with those who continued for 9 years. The number of fractures was low and did not significantly differ by treatment. While generally safe, there was a small increase in cardiac arrhythmias (combined serious and non-serious) in the Z9 group but no significant imbalance in other safety parameters. The results suggest almost all patients who have received six annual ZOL infusions can stop medication for up to 3 years with apparent maintenance of benefits. This article is protected by copyright. All rights reserved.
Resumo:
UNLABELLED Treatment effects over 2 years of teriparatide vs. ibandronate in postmenopausal women with osteoporosis were compared using lumbar spine bone mineral density (BMD) and trabecular bone score (TBS). Teriparatide induced larger increases in BMD and TBS compared to ibandronate, suggesting a more pronounced effect on bone microarchitecture of the bone anabolic drug. INTRODUCTION The trabecular bone score (TBS) is an index of bone microarchitecture, independent of bone mineral density (BMD), calculated from anteroposterior spine dual X-ray absorptiometry (DXA) scans. The potential role of TBS for monitoring treatment response with bone-active substances is not established. The aim of this study was to compare the effects of recombinant human 1-34 parathyroid hormone (teriparatide) and the bisphosphonate ibandronate (IBN), on lumbar spine (LS) BMD and TBS in postmenopausal women with osteoporosis. METHODS Two patient groups with matched age, body mass index (BMI), and baseline LS BMD, treated with either daily subcutaneous teriparatide (N = 65) or quarterly intravenous IBN (N = 122) during 2 years and with available LS BMD measurements at baseline and 2 years after treatment initiation were compared. RESULTS Baseline characteristics (overall mean ± SD) were similar between groups in terms of age 67.9 ± 7.4 years, body mass index 23.8 ± 3.8 kg/m(2), BMD L1-L4 0.741 ± 0.100 g/cm(2), and TBS 1.208 ± 0.100. Over 24 months, teriparatide induced a significantly larger increase in LS BMD and TBS than IBN (+7.6 % ± 6.3 vs. +2.9 % ± 3.3 and +4.3 % ± 6.6 vs. +0.3 % ± 4.1, respectively; P < 0.0001 for both). LS BMD and TBS were only weakly correlated at baseline (r (2) = 0.04) with no correlation between the changes in BMD and TBS over 24 months. CONCLUSIONS In postmenopausal women with osteoporosis, a 2-year treatment with teriparatide led to a significantly larger increase in LS BMD and TBS than IBN, suggesting that teriparatide had more pronounced effects on bone microarchitecture than IBN.
Resumo:
Changes of porosity, permeability, and tortuosity due to physical and geochemical processes are of vital importance for a variety of hydrogeological systems, including passive treatment facilities for contaminated groundwater, engineered barrier systems (EBS), and host rocks for high-level nuclear waste (HLW) repositories. Due to the nonlinear nature and chemical complexity of the problem, in most cases, it is impossible to verify reactive transport codes analytically, and code intercomparisons are the most suitable method to assess code capabilities and model performance. This paper summarizes model intercomparisons for six hypothetical scenarios with generally increasing geochemical or physical complexity using the reactive transport codes CrunchFlow, HP1, MIN3P, PFlotran, and TOUGHREACT. Benchmark problems include the enhancement of porosity and permeability through mineral dissolution, as well as near complete clogging due to localized mineral precipitation, leading to reduction of permeability and tortuosity. Processes considered in the benchmark simulations are advective-dispersive transport in saturated media, kinetically controlled mineral dissolution-precipitation, and aqueous complexation. Porosity changes are induced by mineral dissolution-precipitation reactions, and the Carman-Kozeny relationship is used to describe changes in permeability as a function of porosity. Archie’s law is used to update the tortuosity and the pore diffusion coefficient as a function of porosity. Results demonstrate that, generally, good agreement is reached amongst the computer models despite significant differences in model formulations. Some differences are observed, in particular for the more complex scenarios involving clogging; however, these differences do not affect the interpretation of system behavior and evolution.
Resumo:
UNLABELLED The FREEDOM study and its Extension provide long-term information about the effects of denosumab for the treatment of postmenopausal osteoporosis. Treatment for up to 8 years was associated with persistent reduction of bone turnover, continued increases in bone mineral density, low fracture incidence, and a favorable benefit/risk profile. INTRODUCTION This study aims to report the results through year 5 of the FREEDOM Extension study, representing up to 8 years of continued denosumab treatment in postmenopausal women with osteoporosis. METHODS Women who completed the 3-year FREEDOM study were eligible to enter the 7-year open-label FREEDOM Extension in which all participants are scheduled to receive denosumab, since placebo assignment was discontinued for ethical reasons. A total of 4550 women enrolled in the Extension (2343 long-term; 2207 cross-over). In this analysis, women in the long-term and cross-over groups received denosumab for up to 8 and 5 years, respectively. RESULTS Throughout the Extension, sustained reduction of bone turnover markers (BTMs) was observed in both groups. In the long-term group, mean bone mineral density (BMD) continued to increase significantly at each time point measured, for cumulative 8-year gains of 18.4 and 8.3 % at the lumbar spine and total hip, respectively. In the cross-over group, mean BMD increased significantly from the Extension baseline for 5-year cumulative gains of 13.1 and 6.2 % at the lumbar spine and total hip, respectively. The yearly incidence of new vertebral and nonvertebral fractures remained low in both groups. The incidence of adverse and serious adverse events did not increase over time. Through Extension year 5, eight events of osteonecrosis of the jaw and two events of atypical femoral fracture were confirmed. CONCLUSIONS Denosumab treatment for up to 8 years was associated with persistent reductions of BTMs, continued BMD gains, low fracture incidence, and a consistent safety profile.
Resumo:
As an estimate of plant-available N, this data set contains measurements of inorganic nitrogen (NO3-N and NH4-N, the sum of which is termed mineral N or Nmin) determined by extraction with 1 M KCl solution of soil samples from the main experiment plots of a large grassland biodiversity experiment (the Jena Experiment; see further details below). In the main experiment, 82 grassland plots of 20 x 20 m were established from a pool of 60 species belonging to four functional groups (grasses, legumes, tall and small herbs). In May 2002, varying numbers of plant species from this species pool were sown into the plots to create a gradient of plant species richness (1, 2, 4, 8, 16 and 60 species) and functional richness (1, 2, 3, 4 functional groups). Plots were maintained by bi-annual weeding and mowing. Soil sampling and analysis: Five soil cores (diameter 0.01 m) were taken at a depth of 0 to 0.15 m and 0.15 to 0.3 m of the mineral soil from each of the experimental plots in September 2002. Samples of the soil cores per plot were pooled during each sampling campaign. NO3-N and NH4-N concentrations were determined by extraction of soil samples with 1 M KCl solution and were measured in the soil extract with a Continuous Flow Analyzer (CFA, Skalar, Breda, Netherlands).
Resumo:
As an estimate of plant-available N, this data set contains measurements of inorganic nitrogen (NO3-N and NH4-N, the sum of which is termed mineral N or Nmin) determined by extraction with 1 M KCl solution of soil samples from the main experiment plots of a large grassland biodiversity experiment (the Jena Experiment; see further details below). In the main experiment, 82 grassland plots of 20 x 20 m were established from a pool of 60 species belonging to four functional groups (grasses, legumes, tall and small herbs). In May 2002, varying numbers of plant species from this species pool were sown into the plots to create a gradient of plant species richness (1, 2, 4, 8, 16 and 60 species) and functional richness (1, 2, 3, 4 functional groups). Plots were maintained by bi-annual weeding and mowing. Soil sampling and analysis: Five soil cores (diameter 0.01 m) were taken at a depth of 0 to 0.15 m and 0.15 to 0.3 m of the mineral soil from each of the experimental plots in March and October 2004. Samples of the soil cores per plot were pooled during each sampling campaign. NO3-N and NH4-N concentrations were determined by extraction of soil samples with 1 M KCl solution and were measured in the soil extract with a Continuous Flow Analyzer (CFA, Skalar, Breda, Netherlands).