BACKGROUND Among the various complications associated with total hip arthroplasty(THA)periprosthetic osteolysis and wear phenomena due to the release of metal particles,are two of the most common and have been reporte...BACKGROUND Among the various complications associated with total hip arthroplasty(THA)periprosthetic osteolysis and wear phenomena due to the release of metal particles,are two of the most common and have been reported to be correlated because of inflammatory responses directed towards released particles that generally activate macrophagic osteolytic effects.Therein,new masses known as pseudotumors can appear in soft tissues around a prosthetic implant.To date,there is paucity of reliable data from studies investigating for any association between the above mentioned adverse events.AIM To investigate for the existence of any association between serum and urine concentrations of metal-ions released in THA and periprosthetic osteolysis for modular neck and monolithic implants.METHODS Overall,76 patients were divided into three groups according to the type of hip prosthesis implants:Monoblock,modular with metal head and modular with ceramic head.With an average f-up of 4 years,we conducted a radiological evaluation in order to detect any area of osteolysis around the prosthesis of both the femur and the acetabulum.Moreover,serum and urinary tests were performed to assess the values of Chromium and Cobalt released.Statistical analysis was performed to determine any association between the ion release and osteolysis.RESULTS For the 3 study groups,the monolithic,modular ceramic-headed and modular metal-headed implants had different incidences of osteolysis events,which were higher for the modular implants.Furthermore,the most serious of these(grade 3)were detected almost exclusively for the modular implants with metal heads.A mapping of the affected areas was performed revealing that the highest incidences of osteolysis were evidenced in the pertrochanteric region at the femur level,and in the supero-external region at the acetabular level.Regarding the evaluation of the release of metals-ions from wear processes,serum and urinary chromium and cobalt values were found to be higher in cases of modularity,and even more so for those with metal head.Statistical linear correlation test results suggested positive correlations between increasing metal concentrations and incidences areas of osteolysis.However,no cases of pseudo-tumor were detected.CONCLUSION Future studies are needed to identify risk factors that increase peri-prosthetic metal ion levels and whether these factors might be implicated in the triggering of local events,including osteolysis and aseptic loosening.展开更多
Total recoverable concentration of five elements of concern: Aluminum, Iron, Manganese, Arsenic and Lead (Al, Fe, Mn, As, Pb) were measured by inductively coupled plasma atomic emission spectrometry, and mass spectrom...Total recoverable concentration of five elements of concern: Aluminum, Iron, Manganese, Arsenic and Lead (Al, Fe, Mn, As, Pb) were measured by inductively coupled plasma atomic emission spectrometry, and mass spectrometry. The results show that sediment texture plays a controlling role in the concentrations and their spatial distribution. Principal Component Analysis and Cluster Analysis were used to analyze the grain sizes of the sediments. Result of texture analysis classified the samples into three main components in percentages: sand, silt, and clay. Significant differences among the element concentrations in the three groups were observed, and the concentrations of the elements in each group are reported in this study. Most of the elements have their highest concentrations in the fine-grained samples with clay playing an important role, in comparison with the sand component of the soil/sediment samples. There appears to be a strong correlation between samples with high silt, and clay content with the areas of elevated concentrations for Al, Fe, and Mn. There was a strong correlation between aluminum and lead with clay;lead with silt;and sand with manganese, aluminum, and lead. However, there was no strong relationship between the soil textures and iron or arsenic. All elements measured were statistically significant (at P ≤ 0.05) by watershed. The upland areas, and depositional areas’ spatial variation of element concentrations in the sediments were also observed, which was in line with the spatial distribution of the grain size and was thought to be related to the watersheds hydrological dynamics.展开更多
The study on the solvent extraction for quantitative and selective separation of total rare earth metals from the polymetallic nodule leach liquor was investigated. The typical leach liquor bearing 0. 094 g/L total ra...The study on the solvent extraction for quantitative and selective separation of total rare earth metals from the polymetallic nodule leach liquor was investigated. The typical leach liquor bearing 0. 094 g/L total rare earth, 0. 23 g/L Mn, 0.697 g/L Cu, 0.2 g/L Fe, 0.01 g/L Co and 0.735 g/L Ni was subjected to the removal iron content by precipitation method using Ca（OH）2 at pH 3.95, prior to solvent extraction of rare earth metals. Three different organo-phosphoric acid reagents（D2EHPA, PC88 A, Cyanex 272） were used to ascertain their performances and selectivity towards the loading of rare earth metals in presence of other base metals. Based on the results of eq. pH effect, the performances of above three extractants followed the order as： D2EHPA〉PC88A〉Cyanex 272. To ensure the absence of extraction of base metals（Cu, Co, Ni）, the eq. pH of the solution was optimized at the level of 2.21, though higher rare earth metal extraction efficiency was observed at higher eq. pH with either of the extractants. The complete process flow diagram for substantial recovery of total rare earth was developed using D2 EHPA. Extraction isotherm plot was constructed at A：O=12：1, 3-stages and pHe=2.21, using 0.8 mol/L D2 EHPA and the predicted condition of this study was further confirmed by 6-Cycles Counter Current Simulation（CCS） study. The stripping of total rare earth from loaded organic phase（LO） was conducted using HCl solution. Mc-Cabe Thiele diagram study carried out at A：O=1：5 using 4 mol/L HCl showed that three theoretical stages were needed for quantitative stripping of total rare earth. The subsequent stripped solution resulted thus led to contain total rare earth of 5.6 g/L indicating a very high enrichment of total metals by solvent extraction（SX） process.展开更多
文摘BACKGROUND Among the various complications associated with total hip arthroplasty(THA)periprosthetic osteolysis and wear phenomena due to the release of metal particles,are two of the most common and have been reported to be correlated because of inflammatory responses directed towards released particles that generally activate macrophagic osteolytic effects.Therein,new masses known as pseudotumors can appear in soft tissues around a prosthetic implant.To date,there is paucity of reliable data from studies investigating for any association between the above mentioned adverse events.AIM To investigate for the existence of any association between serum and urine concentrations of metal-ions released in THA and periprosthetic osteolysis for modular neck and monolithic implants.METHODS Overall,76 patients were divided into three groups according to the type of hip prosthesis implants:Monoblock,modular with metal head and modular with ceramic head.With an average f-up of 4 years,we conducted a radiological evaluation in order to detect any area of osteolysis around the prosthesis of both the femur and the acetabulum.Moreover,serum and urinary tests were performed to assess the values of Chromium and Cobalt released.Statistical analysis was performed to determine any association between the ion release and osteolysis.RESULTS For the 3 study groups,the monolithic,modular ceramic-headed and modular metal-headed implants had different incidences of osteolysis events,which were higher for the modular implants.Furthermore,the most serious of these(grade 3)were detected almost exclusively for the modular implants with metal heads.A mapping of the affected areas was performed revealing that the highest incidences of osteolysis were evidenced in the pertrochanteric region at the femur level,and in the supero-external region at the acetabular level.Regarding the evaluation of the release of metals-ions from wear processes,serum and urinary chromium and cobalt values were found to be higher in cases of modularity,and even more so for those with metal head.Statistical linear correlation test results suggested positive correlations between increasing metal concentrations and incidences areas of osteolysis.However,no cases of pseudo-tumor were detected.CONCLUSION Future studies are needed to identify risk factors that increase peri-prosthetic metal ion levels and whether these factors might be implicated in the triggering of local events,including osteolysis and aseptic loosening.
文摘Total recoverable concentration of five elements of concern: Aluminum, Iron, Manganese, Arsenic and Lead (Al, Fe, Mn, As, Pb) were measured by inductively coupled plasma atomic emission spectrometry, and mass spectrometry. The results show that sediment texture plays a controlling role in the concentrations and their spatial distribution. Principal Component Analysis and Cluster Analysis were used to analyze the grain sizes of the sediments. Result of texture analysis classified the samples into three main components in percentages: sand, silt, and clay. Significant differences among the element concentrations in the three groups were observed, and the concentrations of the elements in each group are reported in this study. Most of the elements have their highest concentrations in the fine-grained samples with clay playing an important role, in comparison with the sand component of the soil/sediment samples. There appears to be a strong correlation between samples with high silt, and clay content with the areas of elevated concentrations for Al, Fe, and Mn. There was a strong correlation between aluminum and lead with clay;lead with silt;and sand with manganese, aluminum, and lead. However, there was no strong relationship between the soil textures and iron or arsenic. All elements measured were statistically significant (at P ≤ 0.05) by watershed. The upland areas, and depositional areas’ spatial variation of element concentrations in the sediments were also observed, which was in line with the spatial distribution of the grain size and was thought to be related to the watersheds hydrological dynamics.
基金Project supported by Ministry of Oceans and Fisheries,Korea
文摘The study on the solvent extraction for quantitative and selective separation of total rare earth metals from the polymetallic nodule leach liquor was investigated. The typical leach liquor bearing 0. 094 g/L total rare earth, 0. 23 g/L Mn, 0.697 g/L Cu, 0.2 g/L Fe, 0.01 g/L Co and 0.735 g/L Ni was subjected to the removal iron content by precipitation method using Ca（OH）2 at pH 3.95, prior to solvent extraction of rare earth metals. Three different organo-phosphoric acid reagents（D2EHPA, PC88 A, Cyanex 272） were used to ascertain their performances and selectivity towards the loading of rare earth metals in presence of other base metals. Based on the results of eq. pH effect, the performances of above three extractants followed the order as： D2EHPA〉PC88A〉Cyanex 272. To ensure the absence of extraction of base metals（Cu, Co, Ni）, the eq. pH of the solution was optimized at the level of 2.21, though higher rare earth metal extraction efficiency was observed at higher eq. pH with either of the extractants. The complete process flow diagram for substantial recovery of total rare earth was developed using D2 EHPA. Extraction isotherm plot was constructed at A：O=12：1, 3-stages and pHe=2.21, using 0.8 mol/L D2 EHPA and the predicted condition of this study was further confirmed by 6-Cycles Counter Current Simulation（CCS） study. The stripping of total rare earth from loaded organic phase（LO） was conducted using HCl solution. Mc-Cabe Thiele diagram study carried out at A：O=1：5 using 4 mol/L HCl showed that three theoretical stages were needed for quantitative stripping of total rare earth. The subsequent stripped solution resulted thus led to contain total rare earth of 5.6 g/L indicating a very high enrichment of total metals by solvent extraction（SX） process.
