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1.
Sci Total Environ ; 830: 154706, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35331767

RESUMO

Increasing concentrations of Rare Earth Elements (REE) plus yttrium (REY) are entering the environment due to human activities. The similar chemical behaviour across the whole REY, i.e. the lanthanide series (lanthanum to lutetium) and yttrium, allows their use as tracers, fingerprinting rock-forming processes and fluid-rock interactions in earth science systems. However, their use in fingerprinting waste and particularly low-level radioactive waste has not received much attention, despite the direct use of REE in the nuclear industry and the traditional use of REE as proxies to understand the environmental mobility of the actinide series (actinium to lawrencium). The highly instrumented low-level radioactive waste site at Little Forest (Australia) allows a detailed REY study, investigating interactions with local strata, neighbouring waste forms and shallow groundwater flows. Groundwater samples and solids from cored materials were recovered from 2007 to 2012 from the study site and regional baseline sites in the same geological materials. The REY in water samples were analysed by automated chelation pre-concentration (SeaFast, ESI) followed by ICP-MS determination, while solid samples were analysed using Neutron Activation Analysis (NAA) and X-ray fluorescence scanning (ITRAX). Solid rocks showed no REY departed from typical Upper Crust compositions in either Little Forest or regional background sites. Shallow groundwater from ~4-5 m, at or slightly below waste trench levels, showed water-waste interaction as a marked enrichment, relative to shale-normalised patterns, in samarium, europium and gadolinium, with depleted yttrium. Leachate samples from the neighbouring urban landfill show different REY normalised patterns. REY distribution changes with depth through increased interaction with shales and sandstones. Variations in pH and redox conditions lead to widespread precipitation of Fe-hydroxides, which scavenge REY with differential uptake by precipitating solids, resulting in increases in Y and higher Y/Ho ratio in the groundwater along the flow path. Our study revealed that the Little Forest low-level radioactive waste has a REY fingerprint different to that of groundwater in surrounding land uses. REY can be used to fingerprint diverse waste sources, assess the mobility of lanthanides inferring the mobility of selected actinides, and to trace the fate of REY during groundwater recharge. The approach presented can refine source allocation and trace pollutant mobility in current and legacy urban, mixed and radioactive waste sites around the world.

2.
J Environ Radioact ; 237: 106679, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34118615

RESUMO

This study presents the first measurements of anthropogenic plutonium (239Pu and 240Pu) concentrations and atom ratios (240Pu/239Pu) for Tasmania, in sediment collected from Bathurst Harbour, in the Tasmanian Wilderness World Heritage Area, Australia. The weighted mean 240Pu/239Pu atom ratio measured at this site was 0.172 ± 0.007 which is consistent with published data from mainland Australia and global and Southern Hemisphere averages. The 240Pu/239Pu atom ratios ranged between 0.11 and 0.21 with the earliest recorded 240Pu/239Pu atom ratios being the lowest, suggesting an influence of low atom ratio fallout from nuclear testing in Australia. Post-moratorium fallout 240Pu/239Pu atom ratios were consistent with other records. Lead-210 (210Pb) sediment chronologies indicate sediment accumulation rates have increased since the early part of the 19th century at this location.


Assuntos
Plutônio , Monitoramento de Radiação , Cinza Radioativa , Austrália , Plutônio/análise , Cinza Radioativa/análise , Tasmânia
3.
Prog Transplant ; 30(3): 254-264, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32597328

RESUMO

INTRODUCTION: Adverse symptoms experienced by solid organ transplant recipients remain largely unexplored despite their purported frequency. OBJECTIVE: To characterize patient perspectives on adverse symptoms, identifying the most problematic symptoms and the perceived cause and treatability, and to evaluate their impact on quality of life (QoL) and medication adherence. METHODS: An electronic survey was distributed to members of the Canadian Transplant Association, to characterize perceptions on symptom experience (Modified Transplant Symptom Occurrence and Distress Scale), and QoL (Short Form-12), medication adherence (Basel Assessment of Adherence to Immunosuppressive Medications Scale), demographics, and clinical situation. RESULTS: The questionnaire was distributed to 249 solid organ transplant recipients and achieved a 51% response rate (N = 127). Respondents reported a mean of 25 (standard deviation 10) adverse symptoms each. In women, the most prevalent and distressing symptoms were tiredness, lack of energy, sleep difficulties, difficulty concentrating or memory problems, diarrhea, joint pain, and depression. In men, they were tiredness, flatulence, lack of energy, sleep difficulties, and erectile problems. With the exception of flatulence, these symptoms were more often perceived to be caused by medical conditions rather than by immunosuppressants or other medications. Quality of life was similar to the general public, with mean physical and mental component scores of 47.4 (9.9) and 52.1 (8.2), respectively (relative to a US average of 50 [10]). However, QoL scores inversely correlated to the number of symptoms reported and were higher in patients who perceived all symptoms to be treatable. CONCLUSION: Adverse symptoms may impact patient well-being. Perceived cause and treatability should be further explored.


Assuntos
Imunossupressores/efeitos adversos , Adesão à Medicação/psicologia , Transplante de Órgãos/efeitos adversos , Satisfação do Paciente/estatística & dados numéricos , Qualidade de Vida/psicologia , Transplantados/psicologia , Transplantados/estatística & dados numéricos , Adulto , Idoso , Canadá , Estudos Transversais , Feminino , Humanos , Masculino , Adesão à Medicação/estatística & dados numéricos , Pessoa de Meia-Idade , Transplante de Órgãos/estatística & dados numéricos , Inquéritos e Questionários
4.
J Environ Radioact ; 211: 106081, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31666204

RESUMO

This paper examines the distributions of several anthropogenic radionuclides (239+240Pu, 241Am, 137Cs, 90Sr, 60Co and 3H) at a legacy trench disposal site in eastern Australia. We compare the results to previously published data for Pu and tritium at the site. Plutonium has previously been shown to reach the surface by a bath-tubbing mechanism, following filling of the former trenches with water during intense rainfall events. This has led to some movement of Pu away from the trenched area, and we also provide evidence of elevated Pu concentrations in shallow subsurface layers above the trenched area. The distribution of 241Am is similar to Pu, and this is attributed to the similar chemistry of these actinides and the likely in-situ generation of 241Am from its parent 241Pu. Concentrations of 137Cs are mostly low in surface soils immediately above the trenches. However, similar to the actinides, there is evidence of elevated 137Cs and 90Sr concentrations in shallow subsurface layers above the trenched area. While the subsurface radionuclide peaks suggest a mechanism of subsurface transport, their interpretation is complicated by the presence of soil layers added following disposals and during the subsequent years. The distribution of 90Sr and 137Cs at the ground surface shows some elevated levels immediately above the trenches which were filled during the final 24 months of disposal operations. This is in agreement with disposal records, which indicate that greater amounts of fission products were disposed in this period. The surface distribution of 239+240Pu is also consistent with the disposal documents. Although there is extensive evidence of a mobile tritium plume in groundwater, migration of the other radionuclides by this pathway is limited. The data highlight the importance of taking into account multiple pathways for the mobilisation of key radioactive contaminants at legacy waste trench sites.


Assuntos
Monitoramento de Radiação , Poluentes Radioativos do Solo/análise , Austrália , Poluentes Radioativos da Água
5.
Sci Total Environ ; 656: 250-260, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30504025

RESUMO

This study investigated metal contamination from historical mining in lakes in the Tasmanian Wilderness World Heritage Area (TWWHA) and surrounding region. The largest increase in sedimentation and metal contamination occurred ca. 1930 when open-cut mining commenced and new mining technology was introduced into the region. The geochemical signal of lake sediments changed from reflecting the underlying geology and lithology to that reflecting mining activities. The HYSPLIT air particle trajectory model explains metal distribution in the lakes, with those in the northwest region closest to the mines having the highest metal contamination. Lake metal concentrations since mining activities commenced are in the order: Owen Tarn > Basin Lake > Perched Lake > Lake Dove > Lake Dobson > Lake Cygnus, with Perched Lake and Lakes Dove, Dobson and Cygnus in the TWWHA. Metal contamination affected centres up to 130 km down-wind of mining sites. Enrichment factors (EF) for Pb, Cu, As and Cd are >1 for all lakes, with Owen Tarn and Basin Lake having very high EFs for Cu and Pb (98 and 91, respectively). Pb, Cu, As and Cd concentrations are above the Australia/New Zealand lower sediment guidelines, with Pb, Cu and As above the high guidelines in Owen Tarn and Basin Lake. This study demonstrated the legacy of metal contamination in the TWWHA by mining activities and the consequences of a lack of execution of environmental regulations by past governments in Tasmania.

6.
J Environ Radioact ; 178-179: 377-384, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28687277

RESUMO

At many legacy radioactive waste sites, organic compounds have been co-disposed, which may be a factor in mobilisation of radionuclides at these sites. Tri-butyl phosphate (TBP) is a component of waste streams from the nuclear fuel cycle, where it has been used in separating actinides during processing of nuclear fuels. Analyses of ground waters from the Little Forest Legacy Site (LFLS) in eastern Australia were undertaken using solid-phase extraction (SPE) followed by gas chromatographic mass spectrometry (GCMS). The results indicate the presence of TBP several decades after waste disposal, with TBP only being detected in the immediate vicinity of the main disposal area. TBP is generally considered to degrade in the environment relatively rapidly. Therefore, it is likely that its presence is due to relatively recent releases of TBP, possibly stemming from leakage due to container degradation. The ongoing presence and solubility of TBP has the potential to provide a mechanism for nuclide mobilisation, with implications for long term management of LFLS and similar legacy waste sites.


Assuntos
Água Subterrânea/química , Organofosfatos/análise , Monitoramento de Radiação , Resíduos Radioativos/análise , Poluentes Radioativos da Água/análise , Austrália , Poluentes do Solo/análise
7.
Appl Environ Microbiol ; 83(17)2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28667104

RESUMO

During the 1960s, small quantities of radioactive materials were codisposed with chemical waste at the Little Forest Legacy Site (Sydney, Australia) in 3-meter-deep, unlined trenches. Chemical and microbial analyses, including functional and taxonomic information derived from shotgun metagenomics, were collected across a 6-week period immediately after a prolonged rainfall event to assess the impact of changing water levels upon the microbial ecology and contaminant mobility. Collectively, results demonstrated that oxygen-laden rainwater rapidly altered the redox balance in the trench water, strongly impacting microbial functioning as well as the radiochemistry. Two contaminants of concern, plutonium and americium, were shown to transition from solid-iron-associated species immediately after the initial rainwater pulse to progressively more soluble moieties as reducing conditions were enhanced. Functional metagenomics revealed the potentially important role that the taxonomically diverse microbial community played in this transition. In particular, aerobes dominated in the first day, followed by an increase of facultative anaerobes/denitrifiers at day 4. Toward the mid-end of the sampling period, the functional and taxonomic profiles depicted an anaerobic community distinguished by a higher representation of dissimilatory sulfate reduction and methanogenesis pathways. Our results have important implications to similar near-surface environmental systems in which redox cycling occurs.IMPORTANCE The role of chemical and microbiological factors in mediating the biogeochemistry of groundwaters from trenches used to dispose of radioactive materials during the 1960s is examined in this study. Specifically, chemical and microbial analyses, including functional and taxonomic information derived from shotgun metagenomics, were collected across a 6-week period immediately after a prolonged rainfall event to assess how changing water levels influence microbial ecology and contaminant mobility. Results demonstrate that oxygen-laden rainwater rapidly altered the redox balance in the trench water, strongly impacting microbial functioning as well as the radiochemistry. Two contaminants of concern, plutonium and americium, were shown to transition from solid-iron-associated species immediately after the initial rainwater pulse to progressively more soluble moieties as reducing conditions were enhanced. Functional metagenomics revealed the important role that the taxonomically diverse microbial community played in this transition. Our results have important implications to similar near-surface environmental systems in which redox cycling occurs.


Assuntos
Bactérias/isolamento & purificação , Água Subterrânea/microbiologia , Resíduos Radioativos/análise , Austrália , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Meio Ambiente , Sedimentos Geológicos/análise , Sedimentos Geológicos/microbiologia , Metagenômica , Filogenia , Microbiologia da Água
8.
J Environ Radioact ; 178-179: 411-418, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28689881

RESUMO

The National Health and Medical Research Council and Natural Resource Management Ministerial Council of Australia developed the current Australian Drinking Water Guidelines which recommend an annual radiation dose value of 1 mSv year-1. One of the potential major contributors to the radiation dose from drinking water is radium-228, a naturally occurring radionuclide arising from the thorium decay series. Various methods of analysing for radium-228 in water have been established and adapted by analytical radiochemistry laboratories. Seven laboratories in Australia participated in analysing radium-228 spiked water samples with activity concentrations ranging from 6 mBq L-1 to 20 Bq L-1. The aim of the exercise was to compare and evaluate radium-228 results reported by the participating laboratories, the methods used and the detection limits. This paper presents the outcome of the exercise.


Assuntos
Laboratórios/estatística & dados numéricos , Monitoramento de Radiação , Rádio (Elemento)/análise , Poluentes Radioativos da Água/análise , Austrália
9.
Clin Transplant ; 31(5)2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28239910

RESUMO

Adverse symptoms of immunosuppressants (ASI) impact quality of life (QOL) in solid organ transplant recipients; however, standardized approaches for active ASI surveillance and intervention are lacking. While management is highly clinician dependent, clinician views remain largely unexplored. We surveyed Canadian Society of Transplantation members on their perceptions of ASI including frequency, perceived QOL impact, causal attribution, management strategies, and success. Sixty-one clinicians participated in the survey of 12 ASI (tremor, diarrhea, nausea, constipation, dyspepsia, insomnia, edema, dyspnea, arthralgia, acne, mouth sores, paresthesias), for a 22% response rate. Forty-nine completed the survey (80% completion rate). Diarrhea, dyspepsia, and insomnia were most frequent, requiring management in ≥ 2% of patients by 96%, 90%, and 82% of respondents, respectively. Diarrhea, insomnia, and dyspnea were deemed to have an important QOL impact by 92%, 82%, and 69%. Immunosuppressants were universally implicated as causative of tremor, diarrhea, acne, and mouth sores. Over 80% reported success in managing mouth sores, dyspepsia, and constipation. Management strategies included adjustment of immunosuppressant or other medications, drug therapy, and nonpharmacologic approaches and varied according to perceived causal attribution. More study is needed to compare clinician and patient views. These results will be used to establish priorities for further investigation of ASI.


Assuntos
Transplante de Órgãos/efeitos adversos , Cooperação do Paciente/estatística & dados numéricos , Padrões de Prática Médica , Qualidade de Vida , Perfil de Impacto da Doença , Humanos , Prognóstico , Inquéritos e Questionários
10.
Environ Sci Technol ; 51(4): 2280-2287, 2017 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-28068476

RESUMO

Phosphorus, a critical environmental pollutant, is effectively removed from stormwater by biofiltration systems, mainly via sedimentation and straining. However, the fate of dissolved inflow phosphorus concentrations in these systems is unknown. Given the growing interest in using biofiltration systems to treat other polluted waters, for example greywater, such an understanding is imperative to optimize designs for successful long-term performance. A mass balance method and a radiotracer, 32P (as H3PO4), were used to investigate the partitioning of phosphorus (concentrations of 2.5-3.5 mg/L, >80% was in dissolved inorganic form) between the various biofilter components at the laboratory scale. Planted columns maintained a phosphorus removal efficiency of >95% over the 15-week study period. Plant storage was found to be the dominant phosphorus sink (64% on average). Approximately 60% of the phosphorus retained in the filter media was recovered in the top 0-6 cm. The 32P tracer results indicate that adsorption is the immediate primary fate of dissolved phosphorus in the system (up to 57% of input P). Plant assimilation occurs at other times, potentially liberating sorption sites for processing of subsequent incoming phosphorus. Plants with high nutrient uptake capacities and the ability to efficiently extract soil phosphorus, for example Carex appressa, are, thus, recommended for use in greywater biofilters.


Assuntos
Nitrogênio , Fósforo , Filtração , Plantas , Poluição da Água
11.
Transplantation ; 101(6): 1336-1343, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27367473

RESUMO

BACKGROUND: De novo solid organ transplant recipients (SOTR) have a steep learning curve to acquire medication knowledge. Without adequate knowledge, SOTR are at risk of nonadherence and poor transplant outcomes. METHODS: In this nonblinded, randomized controlled trial, de novo SOTR received standard teaching with or without postdischarge computer-based education (CBE) at home. Primary outcomes were change in knowledge (quiz and recall) and satisfaction, assessed by questionnaires at baseline and 3 months. Adherence was evaluated via self-report and immunosuppressant levels. RESULTS: Two hundred forty-six patients were randomized and 209 completed the 3-month analysis. In the intervention arm, 73 (57.9%) used the CBE program. Change in knowledge quiz score did not differ between groups (4.9% vs 0.6%; P = 0.084), despite a significant increase within the intervention (72.4% vs 77.3%, P = 0.007) but not the control (76.0% vs 76.6%, P = 0.726) arms. Both groups had a significant improvement in recall (intervention, 56.7% vs 82.1%, P < 0.001; control, 51.3% vs 79.7%, P < 0.001), with similar changes in scores (25.4% vs 28.4%, P = 0.55). Change in satisfaction differed between groups (intervention, 1.2% vs control, -4.9%; P = 0.050). There was a significant decline in satisfaction within the control group (88.4% vs 83.5%, P = 0.035), whereas satisfaction was maintained with the intervention (85.6% vs 86.8%, P = 0.55). Adherence was similar in both groups. CONCLUSIONS: Knowledge improved over the study period in both groups, with no incremental benefit for the intervention. Patient satisfaction was maintained with the CBE program. More research is needed to identify barriers to uptake of CBE at home and to develop effective strategies for posttransplant education.


Assuntos
Instrução por Computador , Conhecimentos, Atitudes e Prática em Saúde , Transplante de Órgãos , Cooperação do Paciente , Educação de Pacientes como Assunto/métodos , Satisfação do Paciente , Transplantados/psicologia , Adulto , Feminino , Letramento em Saúde , Humanos , Masculino , Rememoração Mental , Pessoa de Meia-Idade , Ontário , Transplante de Órgãos/efeitos adversos , Estudos Prospectivos , Autocuidado , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento
12.
Environ Sci Technol ; 50(21): 11663-11671, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27704793

RESUMO

Increasing concentrations of dissolved silicate progressively retard Fe(II) oxidation kinetics in the circum-neutral pH range 6.0-7.0. As Si:Fe molar ratios increase from 0 to 2, the primary Fe(III) oxidation product transitions from lepidocrocite to a ferrihydrite/silica-ferrihydrite composite. Empirical results, supported by chemical kinetic modeling, indicated that the decreased heterogeneous oxidation rate was not due to differences in absolute Fe(II) sorption between the two solids types or competition for adsorption sites in the presence of silicate. Rather, competitive desorption experiments suggest Fe(II) was associated with more weakly bound, outer-sphere complexes on silica-ferrihydrite compared to lepidocrocite. A reduction in extent of inner-sphere Fe(II) complexation on silica-ferrihydrite confers a decreased ability for Fe(II) to undergo surface-induced hydrolysis via electronic configuration alterations, thereby inhibiting the heterogeneous Fe(II) oxidation mechanism. Water samples from a legacy radioactive waste site (Little Forest, Australia) were shown to exhibit a similar pattern of Fe(II) oxidation retardation derived from elevated silicate concentrations. These findings have important implications for contaminant migration at this site as well as a variety of other groundwater/high silicate containing natural and engineered sites that might undergo iron redox fluctuations.


Assuntos
Compostos Férricos/química , Compostos Ferrosos , Ferro/química , Oxirredução , Silicatos/química
13.
J Environ Radioact ; 151 Pt 3: 537-41, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26359847

RESUMO

The uranium isotope (233)U is not usually observed in alpha spectra from environmental samples due to its low natural and fallout abundance. It may be present in samples from sites in the vicinity of nuclear operations such as reactors or fuel reprocessing facilities, radioactive waste disposal sites or sites affected by clandestine nuclear operations. On an alpha spectrum, the two most abundant alpha emissions of (233)U (4.784 MeV, 13.2%; and 4.824 MeV, 84.3%) will overlap with the (234)U doublet peak (4.722 MeV, 28.4%; and 4.775 MeV, 71.4%), if present, resulting in a combined (233+234)U multiplet. A technique for quantifying both (233)U and (234)U from alpha spectra was investigated. A series of groundwater samples were measured both by accelerator mass spectrometry (AMS) to determine (233)U/(234)U atom and activity ratios and by alpha spectrometry in order to establish a reliable (233)U estimation technique using alpha spectra. The Genie™ 2000 Alpha Analysis and Interactive Peak Fitting (IPF) software packages were used and it was found that IPF with identification of three peaks ((234)U minor, combined (234)U major and (233)U minor, and (233)U major) followed by interference correction on the combined peak and a weighted average activity calculation gave satisfactory agreement with the AMS data across the (233)U/(234)U activity ratio range (0.1-20) and (233)U activity range (2-300 mBq) investigated. Correlation between the AMS (233)U and alpha spectrometry (233)U was r(2) = 0.996 (n = 10).


Assuntos
Água Subterrânea/análise , Monitoramento de Radiação/métodos , Urânio/análise , Poluentes Radioativos da Água/análise , Análise Espectral
14.
Environ Sci Technol ; 48(17): 10045-53, 2014 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-25126837

RESUMO

During the 1960s, radioactive waste containing small amounts of plutonium (Pu) and americium (Am) was disposed in shallow trenches at the Little Forest Burial Ground (LFBG), located near the southern suburbs of Sydney, Australia. Because of periodic saturation and overflowing of the former disposal trenches, Pu and Am have been transferred from the buried wastes into the surrounding surface soils. The presence of readily detected amounts of Pu and Am in the trench waters provides a unique opportunity to study their aqueous speciation under environmentally relevant conditions. This study aims to comprehensively investigate the chemical speciation of Pu and Am in the trench water by combining fluoride coprecipitation, solvent extraction, particle size fractionation, and thermochemical modeling. The predominant oxidation states of dissolved Pu and Am species were found to be Pu(IV) and Am(III), and large proportions of both actinides (Pu, 97.7%; Am, 86.8%) were associated with mobile colloids in the submicron size range. On the basis of this information, possible management options are assessed.


Assuntos
Amerício/química , Amerício/isolamento & purificação , Locais de Resíduos Perigosos , Plutônio/química , Plutônio/isolamento & purificação , Resíduos Radioativos/análise , Poluentes Radioativos da Água/isolamento & purificação , Austrália , Precipitação Química , Coloides/química , Tamanho da Partícula , Solo , Soluções , Poluentes Radioativos da Água/química
15.
Transplant Res ; 3(1): 1, 2014 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-24387192

RESUMO

BACKGROUND: Literature on the timing of rabbit antithymocyte globulin (rATG) induction and its effects on kidney transplant outcomes is limited. The manufacturer recommends that the first dose be given intra-operatively, however this may present clinical practice risks and challenges. Our objective was to assess the impact of the timing of the first dose of rATG on kidney transplant outcomes. METHODS: Incident kidney transplant recipients (KTR) from January 2002 to December 2009 receiving the first dose of rATG post-operatively (Post, n = 353) or before reperfusion (Pre, n = 124) were evaluated. Outcomes assessed included eGFR at 1-year, delta eGFR (12 versus 1 month), and incidence of biopsy-proven acute rejection, graft loss, death, and a composite of the time-to-event outcomes. The impact of timing on outcomes was adjusted for potential confounders and assessed using linear and Cox regression models. RESULTS: Among 435 KTR surviving with function to 12 months post-transplant, there was no significant difference in mean estimated glomerular filtration rate or eGFR (55.0 versus 56.7 mL/min, P = 0.46) and delta eGFR (1.8 versus 0.3 mL/min, P = 0.40) in Post versus Pre groups, respectively. At a median follow-up of 3 years, the composite endpoint (time to first biopsy-proven acute rejection, graft loss, or death) was similar by timing group (adjusted HR = 0.94; 95% CI: 0.58, 1.53, P = 0.81) in the total study population. CONCLUSIONS: Timing of rATG had no appreciable impact on clinically relevant endpoints in this study cohort. These results support consideration of more flexible timing of the first dose of rATG induction in KTR.

16.
Environ Sci Technol ; 47(23): 13284-93, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24256473

RESUMO

Radioactive waste containing a few grams of plutonium (Pu) was disposed between 1960 and 1968 in trenches at the Little Forest Burial Ground (LFBG), near Sydney, Australia. A water sampling point installed in a former trench has enabled the radionuclide content of trench water and the response of the water level to rainfall to be studied. The trench water contains readily measurable Pu activity (~12 Bq/L of (239+240)Pu in 0.45 µm-filtered water), and there is an associated contamination of Pu in surface soils. The highest (239+240)Pu soil activity was 829 Bq/kg in a shallow sample (0-1 cm depth) near the trench sampling point. Away from the trenches, the elevated concentrations of Pu in surface soils extend for tens of meters down-slope. The broader contamination may be partly attributable to dispersion events in the first decade after disposal, after which a layer of soil was added above the trenched area. Since this time, further Pu contamination has occurred near the trench-sampler within this added layer. The water level in the trench-sampler responds quickly to rainfall and intermittently reaches the surface, hence the Pu dispersion is attributed to saturation and overflow of the trenches during extreme rainfall events, referred to as the 'bathtub' effect.


Assuntos
Monitoramento Ambiental/estatística & dados numéricos , Locais de Resíduos Perigosos/estatística & dados numéricos , Plutônio/análise , Resíduos Radioativos/análise , Poluentes Radioativos do Solo/análise , Poluentes Radioativos da Água/análise , Monitoramento Ambiental/métodos , New South Wales , Contagem de Cintilação
17.
Clin Transplant ; 26(2): E149-57, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22507355

RESUMO

BACKGROUND: Lung transplant recipients have complex drug regimens. Study objectives were to assess drug therapy problems (DTPs), pharmacist recommendations, and patient satisfaction with pharmacist services. METHODS: Using a pharmaceutical care assessment process, pharmacists identified DTPs and made therapeutic recommendations. Number of DTPs identified per pharmacist visit was calculated and compared to standard care visits through retrospective chart review. Potential clinical impact of recommendations was evaluated by blinded clinicians. Patient satisfaction was assessed via survey. RESULTS: Fifty-five DTPs were identified in 43 patients over 50 pharmacist visits (1.05 ± 1.34 DTPs per visit). In these same patients, rate of DTP identification was 0.51 ± 0.64 DTPs per standard visit in the preceding two-wk period (p = 0.018 vs. pharmacist visit). The most common DTPs identified by the pharmacist were adverse drug effect (27%) and untreated indication (25%). Overall, 62% of pharmacist recommendations were rated very significant or significant. Survey return rate was 58% and satisfaction scores ranged from 3 to 5 out of 5. Review of medications and teaching regarding the use of medications received the most "very satisfied" and "highly important" scores. CONCLUSIONS: Pharmacists can make valuable contributions in a lung transplant clinic setting by identifying DTPs and making recommendations with a positive impact on patient outcomes and satisfaction.


Assuntos
Instituições de Assistência Ambulatorial , Transplante de Pulmão , Assistência Farmacêutica , Adolescente , Adulto , Interações Medicamentosas , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polimedicação , Adulto Jovem
18.
Transplantation ; 93(7): 657-65, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22267158

RESUMO

The introduction of generic immunosuppressant medications may present an opportunity for cost savings in solid organ transplantation if equivalent clinical outcomes to the branded counterparts can be achieved. An interprofessional working group of the Canadian Society of Transplantation was established to develop recommendations on the use of generic immunosuppression in solid organ transplant recipients (SOTR) based on a review of the available data. Under current Health Canada licensing requirements, a demonstration of bioequivalence with the branded formulation in healthy volunteers allows for bridging of clinical data. Cyclosporine, tacrolimus, and sirolimus are designated as "critical dose drugs" and are held to stricter criteria. However, whether this provides sufficient guarantee of therapeutic equivalence in SOTR remains controversial, and failure to maintain an appropriate balance of immunosuppression may have serious consequences, including rejection, graft loss, and death. Published evidence supporting therapeutic equivalence of generic formulations in SOTR is lacking. Moreover, in the setting of multiple generic formulations the potential for uncontrolled product switching is a major concern, since generic preparations are not required to demonstrate bioequivalence with each other. Although close monitoring is recommended with any change in formulation, drug product switches are likely to occur without prescriber knowledge and may pose a significant patient safety risk. The advent of generic immunosuppression will require new practices including more frequent therapeutic drug and clinical monitoring, and increased patient education. The additional workload placed on transplant centers without additional funding will create challenges and could ultimately jeopardize patient outcomes. Until more robust clinical data are available and adequate regulatory safeguards are instituted, caution in the use of generic immunosuppressive drugs in solid organ transplantation is warranted.


Assuntos
Medicamentos Genéricos/uso terapêutico , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/efeitos dos fármacos , Imunossupressores/uso terapêutico , Transplante de Órgãos/efeitos adversos , Canadá , Redução de Custos , Análise Custo-Benefício , Custos de Medicamentos , Monitoramento de Medicamentos , Substituição de Medicamentos , Medicamentos Genéricos/efeitos adversos , Medicamentos Genéricos/economia , Medicamentos Genéricos/farmacocinética , Medicina Baseada em Evidências , Rejeição de Enxerto/economia , Rejeição de Enxerto/imunologia , Humanos , Imunossupressores/efeitos adversos , Imunossupressores/economia , Imunossupressores/farmacocinética , Transplante de Órgãos/economia , Patentes como Assunto , Medição de Risco , Equivalência Terapêutica , Resultado do Tratamento
19.
Environ Sci Technol ; 45(13): 5536-42, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21618967

RESUMO

Titanium dioxide (TiO(2)) has often served as a model substrate for experimental sorption studies of environmental contaminants. However, various forms of Ti-oxide have been used, and the different sorption properties of these materials have not been thoroughly studied. We investigated uranium sorption on some thoroughly characterized TiO(2) surfaces with particular attention to the influence of surface area, surface charge, and impurities. The sorption of U(VI) differed significantly between samples. Aggressive pretreatment of one material to remove impurities significantly altered the isoelectric point, determined by an electroacoustic method, but did not significantly impact U sorption. Differences in sorption properties between the various TiO(2) materials were related to the crystallographic form, morphology, surface area, and grain size, rather than to surface impurities or surface charge. In-situ attenuated total reflection Fourier-transform infrared (ATR FT-IR) spectroscopic studies showed that the spectra of the surface species of the TiO(2) samples are not significantly different, suggesting the formation of similar surface complexes. The data provide insights into the effect of different source materials and surface properties on radionuclide sorption.


Assuntos
Propriedades de Superfície , Titânio/química , Urânio/química , Absorção , Cromatografia por Troca Iônica , Ponto Isoelétrico , Espectrometria de Massas , Microscopia Eletrônica de Transmissão , Espectrometria por Raios X , Espectrofotometria Atômica , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
20.
J Environ Radioact ; 102(10): 896-900, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20609501

RESUMO

A technique for the isolation of thorium (Th), plutonium (Pu), americium (Am), uranium (U) and strontium (Sr) isotopes from various environmental matrices has been adapted from a previously published method specific to water samples (Maxwell, 2006). Separation and isolation of the various elemental fractions from a single sub-sample is possible, thereby eliminating the need for multiple analyses. The technique involves sample dissolution, concentration via calcium phosphate co-precipitation, rapid column extraction using TEVA™, TRU™ and Sr-Spec™ resin cartridges, alpha spectrometry for Th, Pu, U and Am and Cerenkov counting for Sr. Various standard reference materials were analysed and chemical yields are in the range of 70-80% for Th, Am, U and Sr and 50-60% for Pu. Sample sizes of up to 10 L for water, 5 g for dry soil and sediment and 10 g for dry vegetation and seaweed can be processed using this technique.


Assuntos
Elementos da Série Actinoide/análise , Monitoramento Ambiental/métodos , Análise Espectral/métodos , Radioisótopos de Estrôncio/análise , Elementos da Série Actinoide/isolamento & purificação , Monitoramento Ambiental/instrumentação , Sedimentos Geológicos/análise , Solo/análise , Poluentes Radioativos do Solo/análise , Poluentes Radioativos do Solo/isolamento & purificação , Análise Espectral/instrumentação , Radioisótopos de Estrôncio/isolamento & purificação , Água/análise , Poluentes Radioativos da Água/análise , Poluentes Radioativos da Água/isolamento & purificação
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