Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 64
Filtrar
Mais filtros

Bases de dados
Tipo de documento
Intervalo de ano de publicação
1.
Ecotoxicol Environ Saf ; 271: 115928, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38215666

RESUMO

Nephrotoxicity is a common adverse effect induced by various chemicals, necessitating the development of reliable toxicity screening models for nephrotoxicity assessment. In this study, we assessed a group of nephrotoxicity indicators derived from different toxicity pathways, including conventional endpoints and kidney tubular injury biomarkers such as clusterin (CLU), kidney injury molecule-I (KIM-1), osteopontin (OPN), and neutrophil gelatinase-associated lipocalin (NGAL), using HK-2 and induced pluripotent stem cells (iPSCs)-derived renal proximal tubular epithelial-like cells (PTLs). Among the biomarkers tested, OPN emerged as the most discerning and precise marker. The predictive potential of OPN was tested using a panel of 10 nephrotoxic and 5 non-nephrotoxic compounds. The results demonstrated that combining OPN with the half-maximal inhibitory concentration (IC50) enhanced the diagnostic accuracy in both cellular models. Additionally, PTLs cells showed superior predictive efficacy for nephrotoxicity compared to HK-2 cells in this investigation. The two cellular models were utilized to evaluate the nephrotoxicity of lanthanum. The findings indicated that lanthanum possesses nephrotoxic properties; however, the degree of nephrotoxicity was relatively low, consistent with the outcomes of in vivo experiments.


Assuntos
Lantânio , Osteopontina , Humanos , Osteopontina/metabolismo , Lantânio/toxicidade , Lantânio/metabolismo , Rim , Túbulos Renais/metabolismo , Biomarcadores/metabolismo
2.
Ecotoxicol Environ Saf ; 267: 115627, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37890244

RESUMO

Rare earth elements (REEs) are emerging as an anticipated pollution in the environment due to their active use in many areas. However, the effects of REEs on the photosynthesis of rice have not been thoroughly explored. Therefore, this study emphasizes how high levels of La(III) affect the thylakoid membrane of rice seedlings, thereby inhibiting photosynthesis and growth. Here, we reported that rice plants treated with La(III) exhibited an increase in La accumulation in the leaves, accompanied by a decrease in chlorophyll content and photosynthetic capacity. La(III) exposure decreased Mg content in leaves, but possibly increased other nutrients including Cu, Mn, and Zn through systemic endocytosis. K-band and L-band appeared in the fluorescence OJIP transients, indicating La(III) stress destroyed the donor and receptor sides of photosystem II (PSII). Numerous reaction centers (RC/CSm) were inactivated by La(III) treatment, which resulted in a reduction in electron transport capacity (decreased ETo/RC and ETo/CSm) and an increase in the dissipation of the excess excitation energy by heat (increased DIo/RC and DIo/CSm). The BN-PAGE analysis of thylakoid membrane protein complexes showed that La(III) induced the degradation of supercomplexes, PSII core, LHCII, PSI core, LHCI, and F1-ATPase binding Cyt b6f complex. Collectively, this study revealed that La(III) causes significant degradation of thylakoid membrane proteins, thereby promoting the decomposition of photosynthetic complexes, ultimately destroying the chloroplast structure and reducing the photosynthetic performance of rice seedlings.


Assuntos
Oryza , Tilacoides , Proteínas de Membrana , Lantânio/toxicidade , Plântula , Fluorescência , Cloroplastos , Fotossíntese , Proteínas das Membranas dos Tilacoides , Clorofila
3.
Ecotoxicol Environ Saf ; 266: 115600, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37862749

RESUMO

Rare earth elements (REEs) have been broad application in a range of industries, including the electronics industry, advanced materials, and medicine. However, health risks associated with REEs received increasing attention. 31 residents (16 males and 15 females) from Bayan Obo mining in Inner Mongolia, China, were enrolled in this study. In total, 677 food samples, the major human exposure matrices (drinking water and duplicate diets), and bio-samples (urine and blood) of 31 participants were obtained. The concentrations of REEs were measured to characterize their external and internal exposures, and the potential health risk of exposure to REE through the ingestion route was analyzed. The results revealed that the detection rate in blood samples (100%) is higher than in urine (32.86%), and only a few REEs were detected in water samples (8.06%), the urine concentrations were considerably lower than in blood. Exposure to REEs through drinking water was considered negligible compared to food intake. Lanthanum and cerium were the most concentrated REEs in food samples. Health risks were calculated based on a dose-response model, the total hazard quotients (THQ) values for all food groups were within normal levels, and the Monte Carlo simulation results show that the 5th, the 50th, and the 95th percentile values of HI were found as 1.45 × 10-2, 3.52 × 10-2, and 9.13 × 10-2, respectively, neither exceeds the threshold, indicating low health risks associated with food intake exposure for this area. The sensitivity results suggest that underweight people are at higher risk, cerium, lanthanum, and yttrium concentrations, and food intake contributes more to health risks. The use of probability distribution methods can improve the accuracy of the results. The cumulative health risk through food intake is negligible, and further attention should be paid to the health risk induced by other routes of exposure to REEs by the local residents.


Assuntos
Cério , Água Potável , Metais Terras Raras , Masculino , Feminino , Humanos , Lantânio , Metais Terras Raras/análise , China , Dieta , Medição de Risco
4.
Artigo em Inglês | MEDLINE | ID: mdl-36497658

RESUMO

Rare earth elements (REEs) are widely found in foods. A high intake of REEs may have associations with adverse effects on human health. This study aimed to investigate the concentrations of REEs in foods in China and to assess the risk of dietary REEs exposure in the Chinese population. The mean concentrations of the total REEs in 27,457 food samples from 11 food categories ranged from 0.04 to 1.41 mg/kg. The daily mean dietary exposure of the total REEs was 1.62 µg/kg BW in the general Chinese population and ranged from 1.61 to 2.80 µg/kg BW in different sex-age groups. The high consumer exposure (95th percentile, P95) was 4.83 µg/kg BW, 9.38% of the temporary ADI (tADI) of REEs (51.5 µg/kg BW). None of the P95 exposure exceeded the tADI in all of the sub-groups. Lanthanum, cerium, and yttrium accounted for approximately 63% of the total exposure of the 16 REEs. The hazard index of 16 REEs was far below 1. Therefore, the health risk of dietary REEs exposure in the general Chinese population was low. No cumulative risk was found for the 16 REEs in China. The results indicate there was no need to stipulate the limits of REEs in foods.


Assuntos
Cério , Metais Terras Raras , Humanos , Exposição Dietética , População do Leste Asiático , Metais Terras Raras/análise , Lantânio , China
5.
Appl Radiat Isot ; 185: 110247, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35452907

RESUMO

A 3.81 × 3.81 cm LaBr3(Ce) detector based portable measurement setup has been developed for in situ gamma spectrometric survey of a contaminated site. This system is suitable for above- and below ground surface gamma spectrometric measurements of 137Cs. However, the minimum detectable activity concentration (MDAC), an important parameter of a measurement system, should be estimated for planning purposes of the gamma spectrometric survey. In this study, the MDAC of 137Cs for the measurement setup was investigated. The efficiency of the measurement setups was calculated from Monte Carlo simulations using MCNP code. The numerical model of the different studied set-ups, used in MCNP, performed well for the known cases. The results show that the MDAC varies with the position of the detector with respect to ground surface. A 5-20 min acquisition time, depending on the detector position, can be sufficient to get a MDAC of about 10% of the exemption limit of 137Cs (100 Bq/kg).


Assuntos
Monitoramento de Radiação , Espectrometria gama , Brometos , Lantânio , Método de Monte Carlo , Espectrometria gama/métodos
6.
Chemosphere ; 286(Pt 1): 131458, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34284222

RESUMO

Excessive phosphorus is one of the main reasons leading to eutrophication that causes severe ecosystem imbalance and negative human health impacts. In this study, several chitosan (CS)/lanthanum (La) hydrogel beads were first synthesized and tested for phosphorus removal. The stable cross-linked CS/La hydrogel bead prepared with the optimized conditions of 10 wt% La/CS and 1.5 mL of 5% glutaraldehyde demonstrated exceptional performance in the removal. It removed phosphate effectively from an aqueous solution in the pH range from 2 to 7. The complete phosphate uptake was achieved at contact time of 6 h under the completely mixing batch condition. The experimental maximum adsorption capacity of 107.7 mg g-1 was observed at solution pH 4. The phosphate adsorption was well described by the Freundlich isotherm and the intraparticle surface diffusion model. Furthermore, the adsorbent was effectively regenerated and reused in a five-cycle adsorption-desorption operation. The removal of phosphate can be attributed to electrostatic attraction and ion exchange. Moreover, the bead was capable of removing heavy metals: copper, zinc and lead. This adsorbent may be served as a cost-effective material for the treatment of phosphorus-contaminated water so as to minimize the occurrence of eutrophication.


Assuntos
Quitosana , Poluentes Químicos da Água , Purificação da Água , Adsorção , Análise Custo-Benefício , Ecossistema , Humanos , Hidrogéis , Concentração de Íons de Hidrogênio , Cinética , Lantânio , Fósforo , Água , Poluentes Químicos da Água/análise
7.
J Colloid Interface Sci ; 601: 242-253, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34082229

RESUMO

It is known that phosphorus is a major contributor to the occurrence of eutrophication. As such, it is of importance to remove it from water. Nanofiltration (NF) has low phosphorus selectivity and requires a relatively high pressure to achieve the separation, though it is capable of removing phosphorus. In this paper, we report our findings of method development on fabrication and application of a lanthanum (La)-incorporated polyethersulfone (PES)/sulfonated polyphenylenesulfone membrane for phosphorus treatment. The performances of membranes fabricated by the in situ and ex situ methods were examined in a series of batch adsorption and dead-end filtration experiments. The membrane fabricated by the in situ method demonstrated higher adsorption capacity (48.0 mg/g), faster kinetics (equilibrium in 6 h) and higher water permeance (>100 LMH/bar), which outperformed that by the ex situ method. Furthermore, the PES/La (in situ) membrane showed a comparable phosphate removal with a much higher permeance (about 20 times) than the NF90 (a nanofiltration commercial membrane). Moreover, the multiple cycles of filtration study showed that the membrane was reused satisfactorily in treating low-phosphate contaminated water and meeting the stringent phosphate standard limit of 0.15 mg/L. The removal of phosphate by the membranes was attributed to the mechanisms of ion exchange and electrostatic attraction/complexation. The study reported here provides a better approach in fabrication of functionalized membrane for water treatment, such as phosphate removal in either batch adsorption or membrane filtration process.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Lantânio , Fosfatos , Fósforo , Polímeros , Sulfonas , Ultrafiltração
8.
Radiat Prot Dosimetry ; 192(3): 309-320, 2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33320200

RESUMO

Gamma-ray spectra were measured using a LaBr$_{3}$(Ce) spectrometer during the outage periods, aiming at quantifying the gamma source term of radiation workers' exposure, at the CANDU nuclear power reactors, for the purposes of eye lens dosimetry. The spectra were measured inside the boiler rooms, of the Bruce Power and Ontario Power Generation (OPG) CANDU nuclear power plants, where workers are exposed to relatively high dose rates radiation fields during the maintenance work. Prior to measurements at the CANDU reactors, the pulse shaping parameters of the gamma spectrometer were optimised for high rates gamma fields, up to an input rates of 120 kcps, in order to accomplish a high output rate with a reasonable energy resolution. In parallel, the response of the LaBr$_{3}$(Ce) detector was characterized by experiments and Monte Carlo simulations. The gamma spectra measured at the CANDU reactors were reported in terms of the gamma-ray fluence rate spectrum. In all measured data, $^{60}$Co and $^{95}$Nb were main contributors of the gamma fields. The measured spectra have been used to calculate the dosimetric quantities of interest: personal dose equivalents H$_{p}$(10) and H$_{p}$(0.07) and eye lens absorbed dose.


Assuntos
Cristalino , Centrais Nucleares , Brometos , Humanos , Lantânio , Método de Monte Carlo , Radiometria
9.
Physiol Meas ; 41(7): 075014, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32392547

RESUMO

OBJECTIVES: Lanthanum (La) retention in bone has been shown to occur in individuals who are orally administered lanthanum carbonate (LaC), a drug to treat hyperphosphatemia. The breakdown of LaC in the gastrointestinal tract into La3+ and carbonate ions results in residual quantities of La being deposited in bone. We previously reported on a non-invasive x-ray fluorescence (XRF) system that was developed to quantify bone La concentrations and applied it to a series of excised cadaver tibiae. However, given interpatient variability in bone shape and size, differential signal attenuation that occurs in bone and tissue, patient movement and overlying tissue thickness at the measurement site, quantifying bone La concentrations during in vivo measurements in live subjects needs to be investigated further along with the radiation dose associated with the measurement. APPROACH: Coherent normalization was investigated as a function of overlying tissue thickness, source-subject distance and bone radius through Monte Carlo simulation and experimental work. This was accomplished by observing the ratio of the net La K x-ray peak area to the coherently scattered peak area at 59.5 keV. In addition, the dose delivered during a 2000 s measurement was determined using radiochromic film. MAIN RESULTS: The coherent normalization of the La x-ray signal was shown to be independent of overlying tissue thickness, source-subject movement and bone radius, which indicates that this normalization procedure can correct for these factors. The equivalent skin dose and effective dose were 18.0 mSv and 3.2 µSv, respectively for a five-year-old. SIGNIFICANCE: While coherent normalization for the bone lead (Pb) and bone gadolinium (Gd) systems has been shown to be successful, we also report that this normalization procedure can correct for these interpatient variabilities in the in vivo 241Am-La K XRF system.


Assuntos
Osso e Ossos/diagnóstico por imagem , Lantânio , Pré-Escolar , Fluorescência , Humanos , Hiperfosfatemia/tratamento farmacológico , Lantânio/análise , Método de Monte Carlo , Imagens de Fantasmas , Doses de Radiação , Espectrometria por Raios X , Raios X
10.
Molecules ; 25(10)2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32408647

RESUMO

The reaction of the Schiff base ligand o-OH-C6H4-CH=N-C(CH2OH)3, H4L, with Ni(O2CMe)2∙4H2O and lanthanide nitrate salts in a 4 : 2 : 1 ratio lead to the formation of the trinuclear complexes [Ni2Ln(H3L)4(O2CMe)2](NO3) (Ln = Sm (1), Eu (2), Gd (3), Tb (4)). The complex cations contain the strictly linear NiII-LnIII-NiII moiety. The central LnIII ion is bridged to each of the terminal NiII ions through two deprotonated phenolato groups from two different ligands. Each terminal NiII ion is bound to two ligands in distorted octahedral N2O4 environment. The central lanthanide ion is coordinated to four phenolato oxygen atoms from the four ligands, and four carboxylato oxygen atoms from two acetates which are bound in the bidentate chelate mode. The lattice structure of complex 4 consists of two interpenetrating, supramolecular diamond like lattices formed through hydrogen bonds among neighboring trinuclear clusters. The magnetic properties of 1-4 were studied. For 3 the best fit of the magnetic susceptibility and isothermal M(H) data gave JNiGd = +0.42 cm-1, D = +2.95 cm-1 with gNi = gGd = 1.98. The ferromagnetic nature of the intramolecular Ni···Gd interaction revealed ground state of total spin S = 11/2. The magnetocaloric effect (MCE) parameters for 3 show that the change of the magnetic entropy (-ΔSm) reaches a maximum of 14.2 J kg-1 K-1 at 2 K. A brief literature survey of complexes containing the NiII-LnIII-NiII moiety is discussed in terms of their structural properties.


Assuntos
Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Lantânio/química , Campos Magnéticos , Níquel/química , Ligantes , Estrutura Molecular , Bases de Schiff/síntese química , Bases de Schiff/química
11.
Physiol Meas ; 40(8): 085006, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31422953

RESUMO

OBJECTIVES: Lanthanum (La) and gadolinium (Gd) are known to deposit in bone of exposed populations, namely those who are orally administered lanthanum carbonate (LaC, La2(CO3)3) or are injected with Gd-based contrast agents, respectively. In this work, bone La and Gd concentrations from the environment and diet were measured using x-ray fluorescence in ten post-mortem human tibiae. As a secondary objective, bone barium (Ba) and iodine concentrations were estimated. APPROACH: Two calibration lines were produced for La and Gd and the minimum detection limits (MDLs) of the system were determined using a 180° irradiation-detection geometry. MAIN RESULTS: The MDLs of the system were 0.4 µg La g-1 bone mineral and 0.5 µg Gd g-1 bone mineral. The mean concentrations were -0.02 ± 0.1 µg La g-1 bone mineral and 0.1 ± 0.2 µg Gd g-1 bone mineral in tibiae. The average Ba and iodine concentrations estimated from the experimental La calibration line and Monte-Carlo derived sensitivity factors were determined to be 3.4 ± 0.8 µg Ba g-1 bone mineral and -0.5 ± 0.3 µg iodine g-1 bone mineral. Since it was discovered that four donors previously received an iodine-based contrast agent, the mean concentrations in these donors was 27.8 ± 28.4 µg iodine g-1 bone mineral. SIGNIFICANCE: The XRF system has determined baseline concentrations of these four heavy metals in trace quantities from natural exposure pathways (with the exception of iodine in four donors). This indicates that the system can measure low levels in ex vivo tibiae samples and can potentially be further developed for in vivo studies involving live subjects who are directly exposed to these metals.


Assuntos
Bário/análise , Gadolínio/análise , Iodo/análise , Lantânio/análise , Espectrometria por Raios X , Tíbia/química , Autopsia , Humanos , Limite de Detecção , Método de Monte Carlo , Imagens de Fantasmas
12.
J Am Soc Nephrol ; 30(6): 1096-1108, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31085679

RESUMO

BACKGROUND: Higher serum phosphate and fibroblast growth factor-23 (FGF23) levels may be modifiable to prevent cardiovascular disease in CKD. Short-term studies have reported modest efficacy in phosphate and FGF23 reduction with intestinal phosphate binders in CKD. METHODS: To investigate effects of lanthanum carbonate (LC; a phosphate binder) and/or nicotinamide (NAM; an inhibitor of active intestinal phosphate transport) on serum phosphate and FGF23 in stage 3b/4 CKD, we conducted a randomized trial among individuals with eGFR 20-45 ml/min per 1.73 m2 to NAM (750 mg twice daily) plus LC (1000 mg thrice daily), NAM plus LC placebo, LC plus NAM placebo, or double placebo for 12 months. Dual primary end points were change from baseline in serum phosphate and intact FGF23 concentrations. RESULTS: Mean eGFR for the 205 participants was 32ml/min per 1.73 m2. At baseline, serum phosphate was 3.7 mg/dl and median FGF23 was 99 pg/ml (10th, 90th percentiles: 59, 205). Mean rates of change in phosphate increased slightly over 12 months in all groups and did not differ significantly across arms. Similarly, percent changes in FGF23 per 12 months increased for all arms except LC plus placebo, and did not differ significantly across arms. Gastrointestinal symptoms limited adherence. Adverse events rates were similar across arms. CONCLUSIONS: LC and/or NAM treatment did not significantly lower serum phosphate or FGF23 in stage 3b/4 CKD over 12 months. Although these agents appeared safe, intestinal symptoms limited adherence. Reducing phosphate and FGF23 in nondialysis CKD will require new approaches.


Assuntos
Fatores de Crescimento de Fibroblastos/sangue , Lantânio/administração & dosagem , Niacinamida/administração & dosagem , Fosfatos/sangue , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/tratamento farmacológico , Adulto , Método Duplo-Cego , Feminino , Fator de Crescimento de Fibroblastos 23 , Fatores de Crescimento de Fibroblastos/efeitos dos fármacos , Taxa de Filtração Glomerular/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Método de Monte Carlo , Insuficiência Renal Crônica/sangue , Medição de Risco , Índice de Gravidade de Doença , Resultado do Tratamento
13.
Molecules ; 24(6)2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30871164

RESUMO

The use of rare earth elements is a growing trend in diverse industrial activities, leading to the need for eco-friendly approaches to their efficient recovery and reuse. The aim of this work is the development of an environmentally friendly and competitive technology for the recovery of those elements from wastewater. Kinetic and equilibria batch assays were performed with zeolite, with and without bacterial biofilm, to entrap rare earth ions from aqueous solution. Continuous assays were also performed in column setups. Over 90% removal of lanthanum and cerium was achieved using zeolite as sorbent, with and without biofilm, decreasing to 70% and 80%, respectively, when suspended Bacillus cereus was used. Desorption from the zeolite reached over 60%, regardless of the tested conditions. When in continuous flow in columns, the removal yield was similar for all of the rare earth elements tested. Lanthanum and cerium were the elements most easily removed by all tested sorbents when tested in single- or multi-solute solutions, in batch and column assays. Rare earth removal from wastewater in open setups is possible, as well as their recovery by desorption processes, allowing a continuous mode of operation.


Assuntos
Bacillus cereus/crescimento & desenvolvimento , Metais Terras Raras/isolamento & purificação , Águas Residuárias/análise , Zeolitas/química , Adsorção , Cério/isolamento & purificação , Resíduos Industriais , Cinética , Lantânio/isolamento & purificação , Poluentes Químicos da Água , Purificação da Água
14.
Expert Rev Pharmacoecon Outcomes Res ; 19(3): 287-298, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30664365

RESUMO

INTRODUCTION: End-stage renal disease is associated with significant comorbidity and mortality. Among its implications, hyperphosphatemia constitutes a consistent and independent risk factor. The use of benchmark treatment, low-cost calcium-based binders declined due to a potential calcification effect on coronary arteries. AREAS COVERED: Given the increasing prevalence of end-stage renal disease and the high cost of hyperphosphatemia's new primary modality, the non-calcium based phosphate binders, we set-off to systematically assess the economic evaluations of non-calcium containing phosphate binders, sevelamer and lanthanum. The study was performed based on a systematic review of the economic evaluations of sevelamer and lanthanum. The cost-effectiveness profile of the two non-calcium-containing Phosphate Binders compared to calcium-based phosphate binders depends on several factors such as future dialysis costs, utility values, age, survival, and phosphorus levels. EXPERT OPINION: The comparison between the two agents is rather inconclusive; nevertheless, current review suggests that non-calcium-based phosphate binders may yield a positive cost-effectiveness ratio in patients with inadequate phosphorus management and patient with longer life-expectancy. It is crucial that the literature is endowed with more data, specifically on survival, future dialysis costs, and calcification.


Assuntos
Hiperfosfatemia/tratamento farmacológico , Lantânio/administração & dosagem , Sevelamer/administração & dosagem , Quelantes/administração & dosagem , Quelantes/economia , Análise Custo-Benefício , Humanos , Hiperfosfatemia/economia , Falência Renal Crônica/economia , Falência Renal Crônica/terapia , Lantânio/economia , Expectativa de Vida , Diálise Renal/economia , Sevelamer/economia
15.
Value Health ; 21(3): 318-325, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29566839

RESUMO

BACKGROUND: Phosphate binders are used to treat hyperphosphatemia among patients with chronic kidney disease (CKD). OBJECTIVES: To conduct an economic evaluation comparing calcium-free binders sevelamer and lanthanum with calcium-based binders for patients with CKD. METHODS: Effectiveness data were obtained from a recent meta-analysis of randomized trials. Effectiveness was measured as life-years gained and translated to quality-adjusted life-years (QALYs) using utility weights from the literature. A Markov model consisting of non-dialysis-dependent (NDD)-CKD, dialysis-dependent (DD)-CKD, and death was developed to estimate the incremental costs and effects of sevelamer and lanthanum versus those of calcium-based binders. A lifetime horizon was used and both costs and effects were discounted at 1.5%. All costs are presented in 2015 Canadian dollars from the Canadian public payer perspective. Results of probabilistic sensitivity analysis were presented using cost-effectiveness acceptability curves. Sensitivity analyses were conducted for risk pooling methods, omission of dialysis costs, and persistence of drug effects on mortality. RESULTS: Sevelamer resulted in an incremental cost-effectiveness ratio of $106,522/QALY for NDD-CKD and $133,847/QALY for DD-CKD cohorts. Excluding dialysis costs, sevelamer was cost-effective in the NDD-CKD cohort ($5,847/QALY) and the DD-CKD cohort ($11,178/QALY). Lanthanum was dominated regardless of whether dialysis costs were included. CONCLUSIONS: Existing evidence does not clearly support the cost-effectiveness of non-calcium-containing phosphate binders (sevelamer and lanthanum) relative to calcium-containing phosphate binders in DD-CKD patients. Our study suggests that sevelamer may be cost-effective before dialysis onset. Because of the remaining uncertainty in several clinically relevant outcomes over time in DD-CKD and NDD-CKD patients, further research is encouraged.


Assuntos
Carbonato de Cálcio/economia , Análise Custo-Benefício/métodos , Hiperfosfatemia/economia , Lantânio/economia , Insuficiência Renal Crônica/economia , Sevelamer/economia , Adulto , Idoso , Carbonato de Cálcio/administração & dosagem , Quelantes/administração & dosagem , Quelantes/economia , Feminino , Humanos , Hiperfosfatemia/tratamento farmacológico , Hiperfosfatemia/epidemiologia , Lantânio/administração & dosagem , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto/economia , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/epidemiologia , Sevelamer/administração & dosagem
16.
Am J Kidney Dis ; 71(2): 246-253, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29195858

RESUMO

Medicare costs for phosphate binders for US dialysis patients and patients with chronic kidney disease enrolled in Medicare Part D exceeded $1.5 billion in 2015. Previous data have shown that Part D costs for mineral and bone disorder medications increased faster than costs for all Part D medications for dialysis patients. Despite extensive use of phosphate binders and escalating costs, conclusive evidence is lacking that they improve important clinical end points in dialysis patients or non-dialysis-dependent patients with chronic kidney disease. Using dialysis patient data from the US Renal Data System and laboratory information from the Centers for Medicare & Medicaid Services (CMS) CROWNWeb data, we update information on trends in phosphate-binder use, calcium and phosphorus values, and costs for Medicare-covered dialysis patients. We discuss these results in the context of evidence from clinical trials, meta-analyses, and observational studies evaluating phosphate-binder efficacy, safety, comparative effectiveness, and cost-effectiveness. Based on our analysis, we note a need for US Food and Drug Administration guidance regarding clinical evaluation of new phosphate binders, and we suggest that it would be in CMS' best interest to fund a clinical trial to assess whether lower versus higher phosphate concentrations improve hard clinical outcomes, and if so, whether particular phosphate binders are superior to placebo or other binders in improving these outcomes.


Assuntos
Hiperfosfatemia/tratamento farmacológico , Falência Renal Crônica , Lantânio , Diálise Renal , Sevelamer , Cálcio/sangue , Quelantes/economia , Quelantes/uso terapêutico , Controle de Medicamentos e Entorpecentes/métodos , Controle de Medicamentos e Entorpecentes/organização & administração , Custos de Cuidados de Saúde , Humanos , Hiperfosfatemia/etiologia , Falência Renal Crônica/sangue , Falência Renal Crônica/economia , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/terapia , Lantânio/economia , Lantânio/uso terapêutico , Medicare Part D , Avaliação das Necessidades , Fósforo/sangue , Diálise Renal/economia , Diálise Renal/métodos , Diálise Renal/estatística & dados numéricos , Sevelamer/economia , Sevelamer/uso terapêutico , Estados Unidos/epidemiologia
17.
Phys Med Biol ; 63(1): 015026, 2017 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-29286003

RESUMO

135La has favorable nuclear and chemical properties for Auger-based targeted internal radiotherapy. Here we present detailed investigations of the production, emissions, and dosimetry related to 135La therapy. 135La was produced by 16.5 MeV proton irradiation of metallic natBa on a medical cyclotron, and was isolated and purified by trap-and-release on weak cation-exchange resin. The average production rate was 407 ± 19 MBq µA-1 (saturation activity), and the radionuclidic purity was 98% at 20 h post irradiation. Chemical separation recovered > 98 % of the 135La with an effective molar activity of 70 ± 20 GBq µmol-1. To better assess cellular and organ dosimetry of this nuclide, we have calculated the x-ray and Auger emission spectra using a Monte Carlo model accounting for effects of multiple vacancies during the Auger cascade. The generated Auger spectrum was used to calculate cellular S-factors. 135La was produced with high specific activity, reactivity, radionuclidic purity, and yield. The emission spectrum and the dosimetry are favorable for internal radionuclide therapy.


Assuntos
Ciclotrons , Elétrons/uso terapêutico , Lantânio/uso terapêutico , Método de Monte Carlo , Neoplasias/radioterapia , Compostos Radiofarmacêuticos/uso terapêutico , Humanos , Radiometria
18.
Environ Sci Technol ; 51(24): 14436-14444, 2017 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-29120610

RESUMO

A comprehensive component-level assessment of several strategic and minor metals (SaMMs), including copper, manganese, magnesium, nickel, tin, niobium, light rare earth elements (LREEs; lanthanum, cerium, praseodymium, neodymium, promethium, and samarium), cobalt, silver, tungsten, heavy rare earth elements (yttrium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium), and gold, use in the 2013 model year Ford Fiesta, Focus, Fusion, and F-150 is presented. Representative material contents in cars and light-duty trucks are estimated using comprehensive, component-level data reported by suppliers. Statistical methods are used to accommodate possible errors within the database and provide estimate bounds. Results indicate that there is a high degree of variability in SaMM use and that SaMMs are concentrated in electrical, drivetrain, and suspension subsystems. Results suggest that trucks contain greater amounts of aluminum, nickel, niobium, and silver and significantly greater amounts of magnesium, manganese, gold, and LREEs. We find tin and tungsten use in automobiles to be 3-5 times higher than reported by previous studies which have focused on automotive electronics. Automotive use of strategic and minor metals is substantial, with 2013 vehicle production in the United States, Canada, EU15, and Japan alone accounting for approximately 20% of global production of Mg and Ta and approximately 5% of Al, Cu, and Sn. The data and analysis provide researchers, recyclers, and decision-makers additional insight into the vehicle content of strategic and minor metals of current interest.


Assuntos
Automóveis , Metais , Canadá , Japão , Lantânio , Neodímio , Praseodímio
19.
Drugs ; 77(11): 1155-1186, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28584909

RESUMO

As kidney disease progresses, phosphorus retention also increases, and phosphate binders are used to treat hyperphosphatemia. Clinicians prescribe phosphate binders thinking that reducing total body burden of phosphorus may decrease risks of mineral and bone disorder, fractures, cardiovascular disease, progression of kidney disease, and mortality. Recent meta-analyses suggest that sevelamer use results in lower mortality than use of calcium-containing phosphate binders. However, studies included in meta-analyses show significant heterogeneity, and exclusion or inclusion of specific studies alters results. Since no long-term studies have been conducted to determine whether treatment with any phosphate binder is better than placebo on any hard clinical endpoint (including mortality), it is unclear whether possible benefit with sevelamer represents net benefit of sevelamer, net harm with calcium-containing phosphate binders, or both. Although one meta-analysis suggested that calcium acetate may be more efficacious gram for gram than calcium carbonate as a binder, calcium acetate did not reduce hypercalcemia, and gastrointestinal intolerance was higher. Data are insufficient to determine whether calcium acetate provides lower risk of vascular calcification than calcium carbonate. Fears of lanthanum accumulation in the central nervous system or bone with long-term treatment do not appear to be warranted. Newer iron-containing phosphate binders have potential benefits, such as lower pill burden (sucroferric oxyhydroxide) and improved iron parameters (ferric citrate). The biggest challenge to phosphate binder efficacy is non-adherence. This article reviews the current knowledge regarding safety, effectiveness, and adherence with currently marketed phosphate binders and those in development.


Assuntos
Quelantes/uso terapêutico , Hiperfosfatemia/tratamento farmacológico , Lantânio/uso terapêutico , Fosfatos/metabolismo , Insuficiência Renal Crônica/tratamento farmacológico , Compostos de Cálcio/efeitos adversos , Compostos de Cálcio/metabolismo , Compostos de Cálcio/uso terapêutico , Quelantes/efeitos adversos , Quelantes/economia , Quelantes/farmacologia , Custos de Medicamentos , Compostos Férricos/efeitos adversos , Compostos Férricos/metabolismo , Compostos Férricos/uso terapêutico , Humanos , Hiperfosfatemia/etiologia , Lantânio/metabolismo , Lantânio/farmacologia , Metanálise como Assunto , Fosfatos/sangue , Insuficiência Renal Crônica/complicações , Sevelamer/uso terapêutico
20.
ACS Comb Sci ; 19(6): 377-385, 2017 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-28463477

RESUMO

Investment in brighter sources and larger and faster detectors has accelerated the speed of data acquisition at national user facilities. The accelerated data acquisition offers many opportunities for the discovery of new materials, but it also presents a daunting challenge. The rate of data acquisition far exceeds the current speed of data quality assessment, resulting in less than optimal data and data coverage, which in extreme cases forces recollection of data. Herein, we show how this challenge can be addressed through the development of an approach that makes routine data assessment automatic and instantaneous. By extracting and visualizing customized attributes in real time, data quality and coverage, as well as other scientifically relevant information contained in large data sets, is highlighted. Deployment of such an approach not only improves the quality of data but also helps optimize the usage of expensive characterization resources by prioritizing measurements of the highest scientific impact. We anticipate our approach will become a starting point for a sophisticated decision-tree that optimizes data quality and maximizes scientific content in real time through automation. With these efforts to integrate more automation in data collection and analysis, we can truly take advantage of the accelerating speed of data acquisition.


Assuntos
Difração de Raios X/métodos , Brometos/química , Ensaios de Triagem em Larga Escala/métodos , Lantânio/química , Razão Sinal-Ruído
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA