Selective lithium separation from desalination concentrates via the synergy of extractant mixtures

Seawater reverse osmosis (SWRO) desalination plants generate high volumes of concentrates, which contain, in addition to major salts, some elements of growing interest in minor concentrations. This is the case of lithium, highly demanded in the battery industry. In this work, the separation of Li+ from model SWRO brines has been evaluated by obtaining Li+ extraction curves with the combination of extractants DBM-TOPO and FDOD-TOPO, proving that both mixtures are capable of extracting Li+ under basic pH conditions, due to the keto-enolic tautomerism of the b-diketones. Li+ extraction values of 95.4 % for DBM-TOPO (pH = 12.2) and 100 % for FDOD-TOPO (pH = 9.0) were achieved. This behaviour was verified by the FT-IR analysis of the sample before and after the Li+ extraction. Finally, the selective separation of Li+ against other cations, such as Na+, K+, Mg2+, Ca2+ and Sr2+, present in the model brines at higher concentrations, was determined. Under mentioned experimental conditions, these cations are not extracted, reaching to Li+ selective separation close to 100 %. This study shows the first results on the selective extraction of lithium in complex SWRO brines, fostered through promising extractants mixtures showing a synergic effect towards Li+ in such multicomponent matrices.This research was developed in the framework of the projects PID2020-115409RB-I00, PDC2021-120786-I00 and TED2021-129874B-I00 financed by the Ministry of Science and Innovation (Spain). Elena Fernández-Escalante is grateful for the predoctoral contract PRE2021-100160

Changes in the number of circulating TCM and TEM subsets in renal transplantation: relationship with acute rejection and induction therapy

Effector (TEM) and central memory (TCM) T cells have been recently described as the main memory T-cell subsets generated after primary immune response, with a potential role in graft rejection after rechallenge with alloantigen. Because of their effector function, they could be involved in driving the response against the allograft, leading to rejection. In this study, we sought to investigate the different memory T-cell subpopulations in peripheral blood from a cohort of 90 patients who underwent consecutive renal transplant, and their association with acute rejection (AR) episodes and induction therapy. Twenty-one of them were monitored in the short term during the first 2 months after transplantation. Three of them suffered an AR but no changes in the circulating levels of either CD4+ or CD8+ TEM were observed as compared with rejection-free renal transplant patients. In total, 69 patients out of 90 were monitored in the long term. Even 2 years after transplantation, maintained increased numbers of peripheral blood CD4+ TEM were observed in patients suffering with AR. Interestingly, induction therapy with thymoglobulin, but not with basiliximab, produced an increase in circulating CD4+ TEM cells at 6 months after transplantation. In conclusion, our data suggest that AR episodes favor the induction of TEM cells in the periphery of renal transplant patients in the long term. It remains to be determined whether such an effect has any impact on long-term renal transplantation

Selective extraction of lithium from seawater desalination concentrates: study of thermodynamic and equilibrium properties using Density Functional Theory (DFT)

Lithium, declared critical raw material by the European Union in 2020, is a competitor to hydrogen as alternative to petroleum. Its use is increasing while reserves are declining, boosting new sources, as seawater desalination concentrates. In this work, a computational study of the most promising extractants, B-diketones and organophosphates and combinations thereof, towards lithium in presence of metal ions found in the concentrates, Na+, K+, Mg2+, Ca2+ and Sr2+ was carried out, via molecular simulation using ab initio Density Functional Theory (DFT). The geometries, reaction energies, and thermodynamic parameters have been evaluated. Using the square of the electronic wave function an electrostatic interaction was confirmed as cation-extractant/s bonding. The complexation reaction energies of the systems formed by a cation and a single extractant display negative [delta]E and [delta]G values, pointing towards stable complexes and spontaneous reactions. The synergic effect of extractants was studied by combining the [beta]-diketones with TOPO (1:1) leading to an increase of [delta]E and [delta]G (absolute value). The extraction coefficient, K, follows the order K(K+) > K(Na+) > K(Li+) > K(Sr2+) > K(Ca2+) > K(Mg2+). In consequence, selectivity Li+ towards cations of the group II was higher, S(Li+/Mg2+) > S(Li+/Ca2+) > S(Li+/Sr2+) for the combined mixtures BTA TOPO and FDOD TOPO and lower towards group I cations, S(Li+/Na+) > S(Li+/K+) for DBM TOPO and LIX54 TOPO. The selectivity of Li+ regarding the rest of the cations and the 16 extractants and mixtures of extractants was lower than the selectivity of Li+ with respect to each cation, being the best value for the DBM TOPO and LIX54 TOPO systems. The results obtained are expected to provide a tool on the behaviour of the most promising of extractants towards Li+ in seawater desalination concentrates.This research was developed in the framework of the project PID2020-115409RB-I00 financed by the Ministry of Science and Innovation (Spain)

Minimal Proteinuria One Year after Transplant is a Risk Factor for Graft Survival in Kidney Transplantation

It is generally accepted that one-year post-transplant proteinuria over 0.5 gm per day has a negative impact on renal graft survival. In this study, the effects of minimal proteinuria less than 0.5 g/day were analyzed in 272 renal recipients who had survived for one year with a functioning graft. Recipients were classified by one-year post-transplant proteinuria: no proteinuria group (<0.2 g/day), minimal proteinuria group (0.2-0.5 g/day), and overt proteinuria group (≥0.5 g/day). Recipients were followed up for 87.1±21 months after transplantation and 38 (13.9%) lost their graft during follow-up. Fifteen percent of patients had minimal proteinuria and 7.8% had overt proteinuria. Five-year graft survival in the minimal proteinuria group was 83.0%, and that in the overt proteinuria group was 70%, in contrast to 97.1% in the no proteinuria group (p=0.01 for trend). In a multivariate analysis, the minimal proteinuria group (relative risk [RR], 4.90; 95% confidence interval [CI], 2.09-11.46) and the overt proteinuria group (RR, 8.75; 95% CI, 3.29-23.29) had higher risks of graft failure than the no proteinuria group. Even minimal proteinuria at one year after transplantation was strongly associated with poor graft outcome. Therefore, it appears logical to consider a low level of proteinuria as a risk factor for graft survival in renal recipients

Regulatory T-cell Number in Peripheral Blood at 1 Year Posttransplant as Predictor of Long-term Kidney Graft Survival

Background: Regulatory T (Treg) cells play a role in limiting kidney transplant rejection and can potentially promote long-term transplant tolerance. There are no large prospective studies demonstrating the utility of peripheral blood Treg cells as biomarkers for long-term graft outcome in kidney transplantation. The aim of our study was to analyze the influence of the absolute number of peripheral blood Treg cells after transplantation on long-term death-censored graft survival. Methods: We monitored the absolute numbers of Treg cells by flow cytometry in nonfrozen samples of peripheral blood in 133 kidney transplant recipients, who were prospectively followed up to 2 years after transplantation. Death-censored graft survival was determined retrospectively in January 2017. Results: The mean time of clinical follow-up was 7.4 ± 2.9 years and 24.1% patients suffered death-censored graft loss (DCGL). Patients with high Treg cells 1 year after transplantation and above the median value (14.57 cells/mm3), showed better death-censored graft survival (5-year survival, 92.5% vs 81.4%, Log-rank P = .030). One-year Treg cells showed a receiver operating characteristic - area under curve of 63.1% (95% confidence interval, 52.9-73.2%, P = 0.026) for predicting DCGL. After multivariate Cox regression analysis, an increased number of peripheral blood Treg cells was a protective factor for DCGL (hazard ratio, 0.961, 95% confidence interval, 0.924-0.998, P = 0.041), irrespectively of 1-year proteinuria and renal function. Conclusions: Peripheral blood absolute numbers of Treg cells 1 year after kidney transplantation predict a better long-term graft outcome and may be used as prognostic biomarkers

A UHPLC-Mass Spectrometry View of Human Melanocytic Cells Uncovers Potential Lipid Biomarkers of Melanoma

Melanoma is the deadliest form of skin cancer due to its ability to colonize distant sites and initiate metastasis. Although these processes largely depend on the lipid-based cell membrane scaffold, our understanding of the melanoma lipid phenotype lags behind most other aspects of this tumor cell. Here, we examined a panel of normal human epidermal and nevus melanocytes and primary and metastatic melanoma cell lines to determine whether distinctive cell-intrinsic lipidomes can discern non-neoplastic from neoplastic melanocytes and define their metastatic potential. Lipidome profiles were obtained by UHPLC-ESI mass-spectrometry, and differences in the signatures were analyzed by multivariate statistical analyses. Significant and highly specific changes in more than 30 lipid species were annotated in the initiation of melanoma, whereas less numerous changes were associated with melanoma progression and the non-malignant transformation of nevus melanocytes. Notably, the “malignancy lipid signature” features marked drops in pivotal membrane lipids, like sphingomyelins, and aberrant elevation of ether-type lipids and phosphatidylglycerol and phosphatidylinositol variants, suggesting a previously undefined remodeling of sphingolipid and glycerophospholipid metabolism. Besides broadening the molecular definition of this neoplasm, the different lipid profiles identified may help improve the clinical diagnosis/prognosis and facilitate therapeutic interventions for cutaneous melanoma.This research was funded in part by grants from the Ministry of Economy; Industry and Competitiveness (RTC-2015-3693-1); Ministry of Science and Innovation (RTI-2018-095134-B-I00); Basque Government (IT971-16; IT1162-19; KK2016-036; KK2017-041 and KK2018-00090) and UPV/EHU (GIU17/066)

Association of the MYH9 gene polymorphisms with chronic renal disease secondary to hypertensive nephrosclerosis, in a Caucasian population

Background: Hypertensive nephrosclerosis (HN) is a chronic kidney disease (CKD) associated to essential hypertension, but their causal relationship is controversial. New evidence suggests that MYH9 gene alterations are associated with HN in African Americans. The aim of this study is to investigate the role of this gene in Spanish Caucasians. Methods: We compare high-risk MYH9 variants of patients with HN recruited according to standard clinical criteria (CKD stages 3-5), with essential hypertensives without renal disease (estimated glomerular filtration rate (eGFR) > 60 ml/min/1,73m2 and albuminuria < 300 mg/g creatinine), and also CKD patients with HN and progressive impairment of renal function with those who were stable. Diabetics were excluded. Results: A blood sample was obtained for genetic study of 238 patients with HN-CKD and 233 hypertensive controls. The rs3752462-T and rs4821480-T (risk alleles for CKD) were more frequent in the CKD group, but without significant difference. We found no differences for these SPNs with blood pressure, creatinine, albuminuria or renal disease progression. Conclusions: The effect of two common MYH9 single nucleotide polymorphisms (SPNs) on the development of CKD secondary to HN in our Spanish Caucasian population is low or zero; in any case less than that found in other, mainly African Americans.Funding: This work was supported by grant Red de Investigación Renal-REDINREN from the Instituto Carlos III, and with funds from the Fundación Renal Iñigo Álvarez de Toledo (Iñigo Álvarez de Toledo Kidney Foundation) in the Molecular Genetics Grou

Incidence of cardiovascular events after kidney transplantation and cardiovascular risk scores: study protocol

<p>Abstract</p> <p>Background</p> <p>Cardiovascular disease (CVD) is the major cause of death after renal transplantation. Not only conventional CVD risk factors, but also transplant-specific risk factors can influence the development of CVD in kidney transplant recipients.</p> <p>The main objective of this study will be to determine the incidence of post-transplant CVD after renal transplantation and related factors. A secondary objective will be to examine the ability of standard cardiovascular risk scores (Framingham, Regicor, SCORE, and DORICA) to predict post-transplantation cardiovascular events in renal transplant recipients, and to develop a new score for predicting the risk of CVD after kidney transplantation.</p> <p>Methods/Design</p> <p>Observational prospective cohort study of all kidney transplant recipients in the A Coruña Hospital (Spain) in the period 1981-2008 (2059 transplants corresponding to 1794 patients).</p> <p>The variables included will be: donor and recipient characteristics, chronic kidney disease-related risk factors, pre-transplant and post-transplant cardiovascular risk factors, routine biochemistry, and immunosuppressive, antihypertensive and lipid-lowering treatment. The events studied in the follow-up will be: patient and graft survival, acute rejection episodes and cardiovascular events (myocardial infarction, invasive coronary artery therapy, cerebral vascular events, new-onset angina, congestive heart failure, rhythm disturbances and peripheral vascular disease).</p> <p>Four cardiovascular risk scores were calculated at the time of transplantation: the Framingham score, the European Systematic Coronary Risk Evaluation (SCORE) equation, and the REGICOR (Registre Gironí del COR (Gerona Heart Registry)), and DORICA (Dyslipidemia, Obesity, and Cardiovascular Risk) functions.</p> <p>The cumulative incidence of cardiovascular events will be analyzed by competing risk survival methods. The clinical relevance of different variables will be calculated using the ARR (Absolute Risk Reduction), RRR (Relative Risk Reduction) and NNT (Number Needed to Treat).</p> <p>The ability of different cardiovascular risk scores to predict cardiovascular events will be analyzed by using the c index and the area under ROC curves. Based on the competing risks analysis, a nomogram to predict the probability of cardiovascular events after kidney transplantation will be developed.</p> <p>Discussion</p> <p>This study will make it possible to determine the post-transplant incidence of cardiovascular events in a large cohort of renal transplant recipients in Spain, to confirm the relationship between traditional and transplant-specific cardiovascular risk factors and CVD, and to develop a score to predict the risk of CVD in these patients.</p

Measurement of galactosyl-deficient IgA1 by the monoclonal antibody KM55 contributes to predicting patients with IgA nephropathy with high risk of long-term progression

Backgroundandobjective:About25%ofpatientswithIgAnephropathy(IgAN)progresstostage5chronickidneydisease(CKD)afteryearsofevolution.Varioustoolshavebeendevelopedinrecentyearsdesignedtopredictwhichofthepatientswillhadpooreroutcomes.Thevalueofcirculatinggalactosyl-deficientIgA1(Gd-IgA1)hasbeenrelatedtoaworseevolutionofIgANinseveralstudies.TherearealsosomepublicationsthatrelatehigherAPRILvalueswithaworseevolution.Recently,anewmethodhasbeendevelopedthatallowsmeasuringthevalueofcirculatingGd-IgA1inasimplerwaythanthosepreviouslyavailable.TheobjectiveofthisstudyistoanalyzetheinfluenceofcirculatingGd-IgA1,measuredbythismethod,ontheprogressionofIgAN.Materialsandmethods:Forty-ninepatientswithadiagnosisofIgANdemonstratedbyrenalbiopsywereselectedinourcenter,withouthavingreceivedpriorimmunosuppressivetreat-ment,forwhomfrozenserumwasavailable.Themedianfollow-upwas4years.Gd-IgA1wasmeasuredbylectin-independentELISAwiththemonoclonalantibodyKM55(IgA1kitCat.No.30111694.IBLInt.,Hamburg,Germany).Likewise,APRILlevelswerealsomeasuredinthesepatients.Results:19(38.8%)patientsreachedstage5CKD.ThefourthquartileofcirculatingGd-IgA1wasrelatedtoahighercumulativeriskofreachingstage5CKDintheKaplan?Meieranalysis(riskatthe5thyear39.4%vs.24.3%,logrankp=0.019).TheGd-IgA1valuewasrelatedto anincreasedriskofCKDstage5(HR1.147,95%CI1.035?1.270,p=0.009),regardlessofglomerularfiltrationrate,proteinuria,thepercentageofsclerosedglomeruliandthevalueofsegmentalsclerosis.WedidnotfindsignificantdifferencesintheAPRILvalues.Conclusions:ThevalueofcirculatingGd-IgA1measuredbythemonoclonalantibodyKM55isrelatedtoaworseevolutionofpatientswithIgANindependentlyofothervariables,soitcouldbeincludedinthestudyofpatientstoimprovethepredictionoftheriskofdiseaseprogression