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Supplemental Digital Content is Available in the Text.In transplantation, the association of tacrolimus exposure with efficacy is better known than with adverse effects. The ExpoTac study explored the relationships between tacrolimus exposure and adverse events (AEs) in kidney transplant patients who benefited from at least 3 measurements of tacrolimus area under the curve (AUC) within 2 years of transplantation. The relationships between tacrolimus AUC, trough concentration C0, peak concentration Cmax, and AEs were explored using univariate analysis and Cox models in 386 patients (1281 sets of exposure biomarkers). Headaches and renal impairment potentially induced by tacrolimus were associated with significantly lower mean dose-standardized exposure biomarkers and a higher proportion of Cmaxvalues above the median. Patients with tremor displayed significantly higher mean AUC0–24(343 ± 79 versus 308 ± 63 hours·mcg/L, P= 0.041). Cox analysis revealed a significant association between (1) the time to the first headache report and mean Cmax, mean AUC0–24, and the proportion of Cmaxvalues above the median (hazard ratios [95% confidence interval] = 0.237 [0.007–0.538]; 7.499 [1.508–29.713]; 5.055 [1.577–17.137]) and (2) the time to first renal impairment report and the proportion of C0values above the median (0.401 [0.098–0.681]). Refining AUC, Cmax, and C0upper limits would help to refine tacrolimus therapeutic ranges and limit the risks of AEs after kidney transplantation.

Supplemental Digital Content is Available in the Text.The Immunosuppressive Drugs Scientific Committee of the International Association of Therapeutic Drug Monitoring and Clinical Toxicology established the second consensus report to guide therapeutic drug monitoring (TDM) of everolimus (EVR) and its optimal use in clinical practice 7 years after the first version was published in 2016. This version provides information focused on new developments that have arisen in the last 7 years. For the general aspects of the pharmacology and TDM of EVR that have retained their relevance, readers can refer to the 2016 document. This edition includes new evidence from the literature, focusing on the topics updated during the last 7 years, including indirect pharmacological effects of EVR on the mammalian target of rapamycin complex 2 with the major mechanism of direct inhibition of the mammalian target of rapamycin complex 1. In addition, various concepts and technical options to monitor EVR concentrations, improve analytical performance, and increase the number of options available for immunochemical analytical methods have been included. Only limited new pharmacogenetic information regarding EVR has emerged; however, pharmacometrics and model-informed precision dosing have been constructed using physiological parameters as covariates, including pharmacogenetic information. In clinical settings, EVR is combined with a decreased dose of calcineurin inhibitors, such as tacrolimus and cyclosporine, instead of mycophenolic acid. The literature and recommendations for specific organ transplantations, such as that of the kidneys, liver, heart, and lungs, as well as for oncology and pediatrics have been updated. EVR TDM for pancreatic and islet transplantation has been added to this edition. The pharmacodynamic monitoring of EVR in organ transplantation has also been updated. These updates and additions, along with the previous version of this consensus document, will be helpful to clinicians and researchers treating patients receiving EVR.

Tacrolimus (TAC) dosing is typically guided by the trough concentration (C0). Yet, significant relationships between TAC C0 and clinical outcomes have seldom been reported or only with adverse events. Large retrospective studies found a moderate correlation between TAC C0 and the area under the curve (AUC), where, for any given C0 value, the AUC varied 3- to 4-fold between patients (and vice versa). However, no randomized controlled trial evaluating the dose adjustment based on TAC AUC has been conducted yet. A few observational studies have shown that the AUC is associated with efficacy and, to a lesser extent, adverse effects. Other studies showed the feasibility of reaching predefined target ranges and reducing underexposure and overexposure. TAC AUC0–12 his now most often assessed using Bayesian estimation, but machine learning is a promising approach. Microsampling devices are well accepted by patients and represent a valuable alternative to venous blood sample collection during hospital visits, especially when a limited sampling strategy is required. As AUC monitoring cannot be proposed very frequently, C0 monitoring has to be used in the interim, which has led to fluctuating doses in patients with an AUC/C0 ratio far from the population mean, because of different dose recommendations between the 2 biomarkers. We proposed estimating the individual AUC/C0 ratio and derived individual C0 targets to be used in between or as a replacement for AUC monitoring. Existing technology and evidence are now sufficient to propose AUC monitoring interspersed with individualized-C0 monitoring for all patients with kidney transplants while collecting real-world data to strengthen the evidence.

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This paper presents a high-precision CMOS fluorescence photometry sensor using a novel lock-in amplification scheme based on switched-biasing and ping-pong auto-zeroing techniques. The CMOS sensor includes two photodiodes and a lock-in amplifier (LIA) operating at 1 kHz. The LIA comprises a differential low-noise amplifier using a novel switched-biasing ping-pong auto-zeroed scheme, an automatic phase aligner, a programmable gain amplifier, a band-pass filter, a mixer, and an output low-pass filter. The design is fabricated in 0.18-µm CMOS process, and the measurement shows that the LIA can retrieve noisy input signals with a dynamic reserve of 42 dB, while consuming only 0.7 mW from a 1.8 V supply voltage. The measured results show that the LIA can detect a wide range of incident light power from 8 nW to 24 µW. The proposed design is encapsulated in a 3D-printed housing allowing for real-time in vitro biomarker detection. This ambulatory platform uses an LED and a fiber optic to convey the excitation light to the sample and retrieve the fluorescence signal. Experiments with a beads solution diluted in PBS demonstrate that the sensor has a sensitivity of 1:100 k. Experimental results obtained in vitro with NIH3T3 mouse cells tagged with membrane dye show the ability of the prototype to detect different densities of cell culture. The portable prototype, which includes optical filters and a small 30 mm × 36 mm × 30 mm printed circuit board enclosed inside the 3D-printed housing, consumes 36.7 mW and weighs 120 g.

Well-characterized biomarkers using reliable quantitative methods are essential for the management of various pathologies such as diabetes, kidney, and liver diseases. Human serum albumin (HSA) isoforms are gaining interest as biomarkers of advanced liver pathologies. In view of the structural alterations observed for HSA, insights into its isoforms are required to establish them as reliable biomarkers. Therefore, a robust absolute quantification method seems necessary. In this study, we developed and validated a far more advanced top-down liquid chromatography–mass spectrometry (LC-MS) method for the absolute quantification of HSA isoforms, using myoglobin (Mb) as an internal standard for quantification and for mass recalibration. Two different quantification approaches were investigated based on peak integration from the deconvoluted spectrum and extracted ion chromatogram (XIC). The protein mixture human serum albumin/myoglobin eluted in well-shaped separated peaks. Mb allowed a systematic mass recalibration for every sample, resulting in extremely low mass deviations compared to conventional deconvolution-based methods. In total, eight HSA isoforms of interest were quantified. Specific-isoform calibration curves showing good linearity were obtained by using the deconvoluted peaks. Noticeably, the HSA ionization behavior appeared to be isoform-dependent, suggesting that the use of an enriched isoform solution as a calibration standard for absolute quantification studies of HSA isoforms is necessary. Good repeatability, reproducibility, and accuracy were observed, with better sensitivity for samples with low albumin concentrations compared to routine biochemical assays. With a relatively simple workflow, the application of this method for absolute quantification shows great potential, especially for HSA isoform studies in a clinical context, where a high-throughput method and sensitivity are needed.

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Interpretation of kidney graft biopsies using the Banff classification is still heterogeneous. In this study, extreme gradient boosting classifiers learned from two large training datasets (n= 631 and 304 cases) where the “reference diagnoses” were not strictly defined following the Banff rules but from central reading by expert pathologists and further interpreted consensually by experienced transplant nephrologists, in light of the clinical context. In three external validation datasets (n= 3744, 589, and 360), the classifiers yielded a mean ROC curve AUC (95%CI) of: 0.97 (0.92–1.00), 0.97 (0.96–0.97), and 0.95 (0.93–0.97) for antibody-mediated rejection (ABMR); 0.94 (0.91–0.96), 0.94 (0.92–0.95), and 0.91 (0.88–0.95) for T cell–mediated rejection; >0.96 (0.90–1.00) with all three for interstitial fibrosis–tubular atrophy. We also developed a classifier to discriminate active and chronic active ABMR with 95% accuracy. In conclusion, we built highly sensitive and specific artificial intelligence classifiers able to interpret kidney graft scoring together with a few clinical data and automatically diagnose rejection, with excellent concordance with the Banff rules and reference diagnoses made by a group of experts. Some discrepancies may point toward possible improvements that could be made to the Banff classification.

Interpretation of kidney graft biopsies using the Banff classification is still heterogeneous. In this study, extreme gradient boosting classifiers learned from two large training datasets (n= 631 and 304 cases) where the “reference diagnoses” were not strictly defined following the Banff rules but from central reading by expert pathologists and further interpreted consensually by experienced transplant nephrologists, in light of the clinical context. In three external validation datasets (n= 3744, 589, and 360), the classifiers yielded a mean ROC curve AUC (95%CI) of: 0.97 (0.92–1.00), 0.97 (0.96–0.97), and 0.95 (0.93–0.97) for antibody‐mediated rejection (ABMR); 0.94 (0.91–0.96), 0.94 (0.92–0.95), and 0.91 (0.88–0.95) for T cell–mediated rejection; >0.96 (0.90–1.00) with all three for interstitial fibrosis–tubular atrophy. We also developed a classifier to discriminate active and chronic active ABMR with 95% accuracy. In conclusion, we built highly sensitive and specific artificial intelligence classifiers able to interpret kidney graft scoring together with a few clinical data and automatically diagnose rejection, with excellent concordance with the Banff rules and reference diagnoses made by a group of experts. Some discrepancies may point toward possible improvements that could be made to the Banff classification. Machine learning algorithms were trained and validated for the automated interpretation of both Banff scores and clinical data and suggest differential weights for elementary lesions, depending upon the diagnosis. Mengel comment page 2719.

It is generally difficult to define the duration of few-cycle laser pulses in the presence of spatiotemporal coupling. The pulse temporal width can indeed vary locally across the pulse front and spatially varying delays can complicate the definition of the temporal pulse length over the whole pulse front. However, the simple formalism of the global pulse length can be used to define the duration of such pulses. The variation of the rms temporal pulse width and the maximum instantaneous intensity of this global pulse is used here to investigate the impact of various aberrations. This is done for a collimated Gaussian few-cycle pulse propagating in a vacuum with no dispersion as a perfect plane wave of uniform, Gaussian, and super-Gaussian spatial profiles and for various local temporal pulse widths. It is shown that the temporal global profile of an aberrated pulse front can lose its Gaussian profile even for low amplitudes of aberration. This results in an increase of the rms temporal width and a decrease of the maximum instantaneous intensity of the global pulse, depending on the type of aberration. This is generally associated with a decrease in the performance for optical systems using few-cycle pulses.

Dix ans après le lancement du programme d’investissement d’avenir (PIA) et la mise en place de ses outils, une des tables rondes des ateliers de Giens a voulu approfondir l’analyse d’impact du PIA en matière de recherche et d’innovation en santé avec comme objectifs de dresser un bilan des actions (bibliométrie, valorisation, notoriété) en partant des constats de 2019 et de l’historique de déploiement du PIA en lien avec le secteur santé, d’analyser le développement du secteur industriel à l’aune des actions du PIA et d’examiner la manière dont les actions spécifiques et le secteur santé en général ont pu s’articuler avec les structures ou organismes existants et contribuer aux politiques de site à travers les Idex/Isite. Cinq clés de succès ont été identifiées, devant constituer une boussole stratégique pour les futurs plans d’action visant à développer l’innovation en santé : une gouvernance en confiance totale entre le responsable du projet et l’ institution, pilotée par les objectifs du projet ; un rôle accru des universités dans le pilotage des objets du PIA, fédérant, dans une politique de site les CHU et les EPST ; une simplification des dispositifs de partenariat public/privé, dans la nature des appels à projets (AAP) et dans la réactivité des établissements ; une aide au développement des écosystèmes locaux, favorisant l’émergence des jeunes chercheurs ; une fertilisation croisée précoce entre monde académique et monde industriel,

The urinary chemokines CXCL9 and CXCL10 are promising noninvasive diagnostic markers of acute rejection (AR) in kidney recipients, but their levels might be confounded by urinary tract infection (UTI) and BK virus (BKV) reactivation. Multiparametric model development and validation addressed these confounding factors in a training set of 391 samples, optimizing the diagnostic performance of urinary chemokines. CXCL9/creatinine increased in UTI and BKV viremia with or without nephropathy (BKVN) (no UTI/leukocyturia/UTI: −0.10/1.61/2.09, P= .0001 and no BKV/viremia/BKVN: −0.10/1.90/2.29, P< .001) as well as CXCL10/creatinine (1.17/2.09/1.98, P< .0001 and 1.13/2.21/2.51, P< .001, respectively). An optimized 8‐parameter model (recipient age, sex, estimated glomerular filtration rate, donor specific antibodies, UTI, BKV blood viral load, CXCL9, and CXCL10) diagnosed AR with high accuracy (area under the curve [AUC]: 0.85, 95% confidence interval [CI]: 0.80‐0.89) and remained highly accurate at the time of screening (AUC: 0.81, 95% CI: 0.48‐1) or indication biopsies (AUC: 0.85, 95% CI: 0.81‐0.90) and within the first year (AUC: 0.86, 95% CI: 0.80‐0.91) or later (AUC: 0.90, 95% CI: 0.84‐0.96), achieving AR diagnosis with an AUC of 0.85 and 0.92 (P< .0001) in 2 external validation cohorts. Decision curve analyses demonstrated the clinical utility of the model. Considering confounding factors rather than excluding them, we optimized a noninvasive multiparametric diagnostic model for AR of kidney allografts with unprecedented accuracy. Inclusion of potential confounding factors of increased urinary chemokine levels led to the development of a robust, noninvasive, 8‐parameter model of acute renal allograft rejection.

Tout récemment, la société savante internationale de pharmacologie-toxicologie biologique a émis des recommandations sur le suivi thérapeutique pharmacologique (STP) du tacrolimus. Cette conférence de consensus fait suite à la première du genre, laquelle avait été publiée en 2009. Dans ce document, la place du STP du tacrolimus pour les quatre principaux organes transplantés (rein, foie, cœur, poumon) est ainsi discutée. Les aspects analytiques, la pharmacogénétique, les approches alternatives de STP et l’utilisation de biomarqueurs sont également abordés. Les recommandations les plus fortes concernent les cibles de concentrations résiduelles qu’il convient d’utiliser en transplantation rénale, hépatique ainsi que dans les autres situations où le tacrolimus est utilisé. Pour la première fois, une cible d’aire sous la courbe est également recommandée pour le suivi des patients transplantés. Enfin, la place des biomarqueurs pharmacodynamique dans le suivi des patients transplantés d’organe fait également l’objet de recommandations.

This Letter demonstrates a method to simultaneously measure the quantitative-phase signal (QPS) of the observed specimen and the refractive index of its surrounding medium (n_m) in a time-resolved manner using a micro-structured coverslip. Such coverslips, easily integrated into perfused live-cell imaging chambers, allow to use various quantitative-phase imaging techniques to achieve this dual measurement. Since QPS is crucially dependent on n_m, the measurement of the latter paves the way for its manipulation in a controlled manner leading to a QPS contrast modulation for appealing applications, including visualizing the interior of cells.

The ionotropic GABAAreceptors represent the main target for different groups of widely used drugs having hypnotic and anxiolytic effects. So far, most approaches used to assess GABA activity involve invasive low -throughput electrophysiological techniques or rely on fluorescent dyes, preventing the ability to conduct noninvasive and thus nonperturbing screens. To address this limitation, we have developed an automated marker-free cell imaging method, based on digital holographic microscopy (DHM). This technology allows the automatically screening of compounds in multiple plates without having to label the cells or use special plates.

The ionotropic GABAAreceptors represent the main target for different groups of widely used drugs having hypnotic and anxiolytic effects. So far, most approaches used to assess GABA activity involve invasive low -throughput electrophysiological techniques or rely on fluorescent dyes, preventing the ability to conduct noninvasive and thus nonperturbing screens. To address this limitation, we have developed an automated marker-free cell imaging method, based on digital holographic microscopy (DHM). This technology allows the automatically screening of compounds in multiple plates without having to label the cells or use special plates.This methodological approach was first validated by screening the GABAAreceptor expressed in HEK cells using a selection of active compounds in agonist, antagonist, and modulator modes. Then, in a second blind screen of a library of 3041 compounds (mostly composed of natural products), 5 compounds having a specific agonist action on the GABAAreceptor were identified. The hits validated from this unbiased screen were the natural products muscimol, neurosteroid alphaxalone, and three compounds belonging to the avermectin family, all known for having an agonistic effect on the GABAAreceptor. The results obtained were exempt from false negatives (structurally similar unassigned hits), and false-positive hits were detected and discarded without the need for performing electrophysiological measurements.The outcome of the screen demonstrates the applicability of our screening by imaging method for the discovery of new chemical structures, particularly regarding chemicals interacting with the ionotropic GABAAreceptor and more generally with any ligand-gated ion channels and transporters.

Si la France dispose de nombreux atouts dans le domaine de la santé pour devenir un leader de l’innovation (l’excellence de ses équipes de recherche, la renommée de son système de santé et de nombreuses startups), force est de constater qu’elle cumule des freins culturels et réglementaires qui limitent une interaction agile et performante entre les industriels et les établissements de santé. La table ronde avait pour objectif d’optimiser l’interface entre les startups/industries et les établissements de santé universitaires ou non. Plusieurs établissements ont mis en place avec succès des équipes et procédures afin de faciliter cette interface, tant vis-à-vis des évaluations des technologies, de prestations de service, de transfert de matériel biologique que de collaboration R&D et de contrat de licence. Cependant, il subsiste un manque de culture entrepreneuriale chez les hospitaliers et les universitaires dont la formation à l’innovation reste insuffisante et la prise en compte, dans l’évolution des carrières, de la valorisation et de la création d’entreprises, inexistante. Les industriels, et en particulier les startups, ont souvent une méconnaissance du milieu hospitalier et de ses contraintes. En conséquence, les recommandations des membres de la table ronde sont les suivantes : (1) favoriser l’acculturation réciproque entre établissements de santé publics et startups, par la formation pluridisciplinaire à l’innovation, la valorisation du personnel porteur de projet et des projets développés au sein de l’établissement, et sensibiliser les entreprises au système de santé ; (2) fournir aux acteurs des moyens et ressources dédiées à l’innovation, en sanctuarisant un temps de travail pour l’innovation, en sécurisant le statut de personnel impliqué, et en accompagnant la recherche de financements ; (3) développer et utiliser des méthodologies et des outils communs, et (4) co-concevoir et co-construire des solutions de santé innovantes, en encourageant l’émergence des lieux de création participative et interdisciplinaire. L’ensemble de ces recommandations devrait aider à rendre l’interface entre les startups/industries et les établissements de santé plus fluide et plus attractive pour les acteurs de la filière santé.

Although France has numerous assets in the realm of health care, such as the excellence of its research teams, the reputation of its healthcare system, and the presence of many startups, all of which are necessary to become a leader in innovation, it also has combined cultural and regulatory barriers that limit the flexibility and efficiency of interactions between companies/startups and public health institutions. Therefore, the aim of the roundtable discussion was to optimize the interface between those businesses and institutions. Several institutions have successfully implemented teams and procedures which aim to facilitate this interface, with regard to assessments of technology, services provided, the transfer of biological material, R&D collaboration, and licensing agreements. However, there is still a notable absence of entrepreneurial culture among hospital and academic research practitioners; their training regarding innovation remains insufficient and business-related value-creation is non-existent in their career evolution. Pharmaceutical companies, and particularly startups, often lack knowledge about hospital environments and their constraints. As a result, the recommendations of the roundtable participants are as follows: (1) promote reciprocal acculturation between public health institutions and startups through multidisciplinary training in innovation, promoting project development and staff recognition within the institution, and improving pharmaceutical companies’ understanding regarding the health care system; (2) provide those involved with means and resources dedicated to innovation by reserving time for innovation at work, securing the status of the staff involved, and aiding in the search for funding; (3) develop and use standard methodologies and tools; and (4) co-design and co-construct innovative health solutions, encouraging the emergence of participatory and interdisciplinary creative spaces. All of these recommendations should help to make the interface between startups/companies and public health institutions more fluid and attractive for those in the health sector.

Background: Selection of expected phenotypes (ie, expressers/non-expressers) is currently used in CYP3A5*3 genotype-based tacrolimus dosing. The authors assessed whether a dosing regimen based on the 3 CYP3A5 genotypes may reduce the occurrence of inadequate exposure.Methods: Tacrolimus whole blood trough levels (C0) were retrieved from a retrospective cohort of 100 kidney transplant recipients treated with a starting dose of 0.15 (non-expressers) or 0.30 (expressers) mg/kg/d. The authors evaluated the occurrence of overexposures (12 < C0< 20 ng/mL) or toxic concentrations (C0≥ 20 ng/mL). These results were used to set up a new strategy based on the 3 distinct CYP3A5 genotypes, which relevance was evaluated in a prospective cohort of 107 patients.Results: In the retrospective cohort, non-expressers exhibited frequent overexposure (63.6%) or toxic C0(20.8%). Among expressers, none of the homozygous *1 carriers exhibited overexposure contrary to 25% of the heterozygotes. Based on these results, new tacrolimus starting doses were set at 0.10, 0.20, and 0.30 mg/kg/d for CYP3A5*3/*3, CYP3A5*1/*3, and CYP3A5*1/*1 genotypes, respectively. Tacrolimus overexposure was reduced in the CYP3A5*3/*3 group (63.6% vs 40%, P= .0038). None of the heterozygous patients exhibited toxic tacrolimus C0. Clinical outcomes were not different between the 2 periods, whatever the genotype. Our results indicate that the best tacrolimus exposure was obtained for doses of 0.10, 0.20, and 0.20 mg/kg/d for CYP3A5*3/3, CYP3A5*1/*3, and CYP3A5*1/*1, respectively.Conclusions: Our results confirm that selecting tacrolimus dosing regimen according to the expected phenotype is appropriate, but that lower than currently recommended doses may be preferable.

Contrary to immune cells, the response of the kidney structural cells in rejection is less established. We performed single-cell RNA sequencing of 18 kidney transplant biopsies from 14 recipients. Single-cell RNA sequencing identified cells from the major compartments of the kidney, next to infiltrated immune cells. Endothelial cells from the glomerulus, peritubular capillaries, and vasa recta showed upregulation of class I and II human leukocyte antigen genes, adhesion molecules, cytokines, and chemokines, suggesting active participation in the alloimmune process, with compartment-specific differences. Epithelial cells including proximal tubular, loop of Henle, and collecting duct cells, also showed increased expression of immune genes. Strikingly, in proximal tubule cells, a strong downregulation of energy metabolism upon inflammation was observed. There was a large overlap between the cell-specific expression changes upon alloimmune inflammation and those observed in 2 large microarray biopsy cohorts. In conclusion, the kidney structural cells, being the main target of the alloimmune process, appear to actively contribute herein, enhancing the damaging effects of the infiltrating immune cells. In epithelial cells, a profound shutdown of metabolism was seen upon inflammation, which is associated with poor kidney function. These observations highlight the critical role of the graft in triggering and sustaining rejection after transplantation.

Despite partial elucidation of the pathophysiology of antibody-mediated rejection (ABMR) after kidney transplantation, it remains largely unclear which of the involved immune cell types determine disease activity and outcome. We used microarray transcriptomic data from a case-control study (n=95) to identify genes that are differentially expressed in ABMR. Given the co-occurrence of ABMR and T-cell–mediated rejection (TCMR), we built a bioinformatics pipeline to distinguish ABMR-specific mRNA markers. Differential expression of 503 unique genes was identified in ABMR, with significant enrichment of natural killer (NK) cell pathways. CIBERSORT (Cell type Identification By Estimating Relative Subsets Of known RNA Transcripts) deconvolution analysis was performed to elucidate the corresponding cell subtypes and showed increased NK cell infiltration in ABMR in comparison to TCMR and normal biopsies. Other leukocyte types (including monocytes/macrophages, CD4 and CD8 T cells, and dendritic cells) were increased in rejection, but could not discriminate ABMR from TCMR. Deconvolution-based estimation of NK cell infiltration was validated using computerized morphometry, and specifically associated with glomerulitis and peritubular capillaritis. In an external data set of kidney transplant biopsies, activated NK cell infiltration best predicted graft failure amongst all immune cell subtypes and even outperformed a histologic diagnosis of acute rejection. These data suggest that NK cells play a central role in the pathophysiology of ABMR and graft failure after kidney transplantation.

This work investigated, in two large cohorts of French renal transplants treated with tacrolimus, the influence of donor and recipient ABCB1,CYP3A4, and CYP3A5genotypes on the risk of allograft loss. A discovery and a replication population of 330 and 369 adult renal transplant patients, each from a different transplantation center and all receiving a tacrolimus‐based immunosuppressive regimen, were retrospectively genotyped. The influence of genetic factors and other known risk factors on allograft loss was investigated using multivariate Cox proportional hazard analyses. The existence of previous transplantations (per unit HR= 1.89 [1.10‐3.26] P= .0216) and the donor ABCB1c.1199GA/AAgenotype (GA/AAvs GG:HR= 3.22 [1.14‐9.09], P= .0288) were associated with an increased risk of allograft loss in the discovery cohort and with graft loss due to humoral rejection in the replication cohort (per unit HR= 2.26 [1.34‐3.81], P= .00229; GA/AAvs GG HR= 3.42 [1.28‐9.16], P= .0142). Genotyping the donor for the ABCB1 c.1199 G>A(exon 11, rs2229109) allele may be of interest before prescribing tacrolimus to the recipient, although this polymorphism is rather rare and its effect may be limited to certain mechanisms of graft loss. This study in two large cohorts of renal transplant patients treated with tacrolimus shows an association between the donor genotype for a single‐nucleotide polymorphism in the efflux transporter P‐glycoprotein and an increased risk of allograft loss in the discovery cohort and with graft loss due to humoral rejection in the replication cohort.

This work investigated, in two large cohorts of French renal transplants treated with tacrolimus, the influence of donor and recipient ABCB1, CYP3A4, and CYP3A5genotypes on the risk of allograft loss. A discovery and a replication population of 330 and 369 adult renal transplant patients, each from a different transplantation center and all receiving a tacrolimus-based immunosuppressive regimen, were retrospectively genotyped. The influence of genetic factors and other known risk factors on allograft loss was investigated using multivariate Cox proportional hazard analyses. The existence of previous transplantations (per unit HR = 1.89 [1.10-3.26] P= .0216) and the donor ABCB1c.1199GA/AA genotype (GA/AAvs GG: HR = 3.22 [1.14-9.09], P= .0288) were associated with an increased risk of allograft loss in the discovery cohort and with graft loss due to humoral rejection in the replication cohort (per unit HR = 2.26 [1.34-3.81], P= .00229; GA/AAvs GG HR = 3.42 [1.28-9.16], P= .0142). Genotyping the donor for the ABCB1 c.1199 G>A(exon 11, rs2229109) allele may be of interest before prescribing tacrolimus to the recipient, although this polymorphism is rather rare and its effect may be limited to certain mechanisms of graft loss.

We propose methods to quantitatively calculate the fluctuation rate of red blood cells with nanometric axial and millisecond temporal sensitivity at the single-cell level by using time-lapse holographic cell imaging. For this quantitative analysis, cell membrane fluctuations (CMFs) were measured for RBCs stored at different storage times. Measurements were taken over the whole membrane for both the ring and dimple sections separately. The measurements show that healthy RBCs that maintain their discocyte shape become stiffer with storage time. The correlation analysis demonstrates a significant negative correlation between CMFs and the sphericity coefficient, which characterizes the morphological type of erythrocyte. In addition, we show the correlation results between CMFs and other morphological properties such as projected surface area, surface area, mean corpuscular volume, and mean corpuscular hemoglobin.

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Cet article passe en revue les principaux constituants d'un spectromètre de masse couplé à la chromatographic liquide (sources d'ionisation à pression atmosphérique, cellules de collision, filtres de masse) et, pour chacun, les principales innovations des constructeurs, leurs avantages proclamés, leur intérêt et leurs applications potentielles en toxicologie. Sont également abordés les modes opératoires généralement utilisés pour les analyses qualitatives ou quantitatives en toxicologie, ainsi que les rares recommandations internationales concernant le nombre d'ions ou de transitions de masse à enregistrer et les variations acceptables de leurs intensités relatives, permettant de profiter réellement de la spécificité de la LC-MS et de la LC-MS/MS au cours d'analyses quantitatives. Il est rappelé à cette occasion que des analyses toxicologiques fiables reposent non seulement sur un matériel performant, mais aussi sur de bonnes pratiques techniques et des opérateurs compétents.

Buprenorphine is a semi-synthetic opioid, prescribed at high dose in France since 1996, as a maintenance therapy for opiate addicts. No study has addressed the potential usefulness of therapeutic drug monitoring (TDM) for high-dose buprenorphine so far. TDM general aims are to decrease the treatment failure rate linked to poor observance or underdosing and the incidence of adverse events due to overdosing. After a brief review of the analytical methods, particularly immunoassays, developed for the determination of buprenorphine in biological matrices, this paper describes the pharmacokinetic and pharmacodynamic causes of the weak blood concentration - effect relationships observed in the population and the use that can be made of urine and hair screening for buprenorphine and other opiates, in order to retrospectively document compliance and treatment efficacy (in terms of abstinence from morphine derivatives). In summary, TDM is apparently of little use for high-dose buprenorphine, except in case of unexplained inefficiency or suspected toxicity, contrary to toxicological screenings for buprenorphine, its main metabolite, morphine and its derivatives.

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Although the management of kidney transplant recipients has greatly improved over recent decades, the assessment of individual risks remains highly imperfect. Individualized strategies are necessary to recognize and prevent immune complications early and to fine-tune immunosuppression, with the overall goal to improve patient and graft outcomes. This review discusses current biomarkers and their limitations, and recent advancements in the field of noninvasive biomarker discovery. A wealth of noninvasive monitoring tools has been suggested that use easily accessible biological fluids such as urine and blood, allowing frequent and sequential assessments of recipient's immune status. This includes functional cell-based assays and the evaluation of molecular expression on a wide spectrum of platforms. Nevertheless, the translation and validation of exploratory findings and their implementation into standard clinical practice remain challenging. This requires dedicated prospective interventional trials demonstrating that the use of these biomarkers avoids invasive procedures and improves patient or transplant outcomes.This comprehensive review discusses current biomarkers and their limitations, and the recent advancements in the field of noninvasive biomarker discovery to make diagnoses and improve care for renal transplant recipients.

CsA and Tac bioavailability may be due in part to polymorphisms in the genes encoding the metabolizing enzymes CYP3A4, CYP3A5 and ABCB1. The authors confirm that CYP3A5*3 donor and recipient genotypes are relevant for CNI dosing in liver transplantation while none of the polymorphisms had an impact on long-term renal function. Supplemental digital content is available in the text.

In this randomized multicenter open-label trial in liver transplant recipients, the authors show that a therapeutic protocol with mycophenolic acid AUC dose adjusted MMF in combination with tacrolimus allows early discontinuation of corticosteroid (at day 1) resulting in lower 1-year posttransplantation diabetes without increasing the incidence of acute rejection.

Therapist adherence describes the quality of interventions according to the imperatives of a treatment model. We examined the relationship between therapist adherence and symptom change in the context of a short-term treatment with respect good psychiatric management (GPM) principles. Based on a parent trial, borderline personality disorder patients (N= 40) benefited from a 10-session intervention. Adherence to GPM was assessed using a GPM Adherence Scale (GPMAS). The psychometric properties of the GPMAS were excellent, and the adherence to GPM explained 16% of the general symptom improvement (t(1) = 2.38, β= 0.40, p= 0.02) and 23% of the borderline symptom improvement (t(1) = 2.46, β= 0.48, p= 0.02). Because GPM adherence predicts the outcome after only 10 sessions, GPMAS is a valuable measure early on in psychiatric practice as part of an initial step to longer-term treatment, to quickly detect problems and correct them.

Supplemental Digital Content is Available in the Text.In 2014, the Immunosuppressive Drugs Scientific Committee of the International Association of Therapeutic Drug Monitoring and Clinical Toxicology called a meeting of international experts to provide recommendations to guide therapeutic drug monitoring (TDM) of everolimus (EVR) and its optimal use in clinical practice. EVR is a potent inhibitor of the mammalian target of rapamycin, approved for the prevention of organ transplant rejection and for the treatment of various types of cancer and tuberous sclerosis complex. EVR fulfills the prerequisites for TDM, having a narrow therapeutic range, high interindividual pharmacokinetic variability, and established drug exposure–response relationships. EVR trough concentrations (C0) demonstrate a good relationship with overall exposure, providing a simple and reliable index for TDM. Whole-blood samples should be used for measurement of EVR C0, and sampling times should be standardized to occur within 1 hour before the next dose, which should be taken at the same time everyday and preferably without food. In transplantation settings, EVR should be generally targeted to a C0of 3–8 ng/mL when used in combination with other immunosuppressive drugs (calcineurin inhibitors and glucocorticoids); in calcineurin inhibitor-free regimens, the EVR target C0range should be 6–10 ng/mL. Further studies are required to determine the clinical utility of TDM in nontransplantation settings. The choice of analytical method and differences between methods should be carefully considered when determining EVR concentrations, and when comparing and interpreting clinical trial outcomes. At present, a fully validated liquid chromatography tandem mass spectrometry assay is the preferred method for determination of EVR C0, with a lower limit of quantification close to 1 ng/mL. Use of certified commercially available whole-blood calibrators to avoid calibration bias and participation in external proficiency-testing programs to allow continuous cross-validation and proof of analytical quality are highly recommended. Development of alternative assays to facilitate on-site measurement of EVR C0is encouraged.

Monitoring immunosuppressive drugs (ISDs) in blood or plasma is still a key therapeutic drug monitoring (TDM) application in clinical settings. Narrow target ranges and severe side effects at drug underexposure or overexposure make accurate and precise measurements a must. This overview prepared by the Immunosuppressive Drugs Scientific Committee of the International Association of Therapeutic Drug Monitoring and Clinical Toxicology is intended to serve as a summary and guidance document describing the current state-of-the-art in the TDM of ISDs.

With current treatment regimens, a relatively high proportion of transplant recipients experience underimmunosuppression or overimmunosuppression. Recently, several promising biomarkers have been identified for determining patient alloreactivity, which help in assessing the risk of rejection and personal response to the drug; others correlate with graft dysfunction and clinical outcome, offering a realistic opportunity for personalized immunosuppression. This consensus document aims to help tailor immunosuppression to the needs of the individual patient. It examines current knowledge on biomarkers associated with patient risk stratification and immunosuppression requirements that have been generally accepted as promising. It is based on a comprehensive review of the literature and the expert opinion of the Biomarker Working Group of the International Association of Therapeutic Drug Monitoring and Clinical Toxicology. The quality of evidence was systematically weighted, and the strength of recommendations was rated according to the GRADE system. Three types of biomarkers are discussed: (1) those associated with the risk of rejection (alloreactivity/tolerance), (2) those reflecting individual response to immunosuppressants, and (3) those associated with graft dysfunction. Analytical aspects of biomarker measurement and novel pharmacokinetic–pharmacodynamic models accessible to the transplant community are also addressed. Conventional pharmacokinetic biomarkers may be used in combination with those discussed in this article to achieve better outcomes and improve long-term graft survival. Our group of experts has made recommendations for the most appropriate analysis of a proposed panel of preliminary biomarkers, most of which are currently under clinical evaluation in ongoing multicentre clinical trials. A section of Next Steps was also included, in which the Expert Committee is committed to sharing this knowledge with the Transplant Community in the form of triennial updates.

In association with therapeutic drug monitoring of immunosuppressive drugs, pharmacogenetics has rapidly emerged as an additional tool to refine dose selection or, more interestingly to select, a priori, the first dose to administer. Pharmacogenetic biomarkers are now readily available in most transplantation centers, at a limited cost and within a limited analytical time frame, which make them compatible with the clinical decision process. However, despite some evidence of clear associations between polymorphisms in genes encoding metabolizing enzymes (CYP3A4/3A5, UGT1A9) or drug transporters (ABCB1, ABCC2, SLCO1B1) and pharmacokinetics of several immunosuppressive drugs, pre-emptive genotyping and selection of the optimal starting dose based on the genetic background of the patient is still rarely performed in clinical practice. The main reason is probably the lack of formal proof that clinical outcome really improves after genotype-based dosing. So far, the only clinical recommendation in relation to pharmacogenetic biomarkers should be a doubling of the starting tacrolimus dose in patients who are CYP3A5 expressers, and even in this case, some authors still do not recommend pre-emptive genotyping but only genotype-based adaptation if the CYP3A5genotype is already known. However, with the rise of new technologies, as next generation sequencing, allowing to obtain pre-emptive genetic information, one must be aware that the question will no longer be whether to genotype or not but rather whether or not to use the information already there. There was therefore a need to update the information available in relation to pharmacogenetic biomarkers for calcineurin inhibitors, mycophenolic acid, and mammalian target of rapamycin inhibitors.

Health-related Quality of Life (HRQOL) can be assessed by the mental composite score and the physical composite score, which improves for most patients after transplant. This prospective study shows that anxiety and muscle weakness are modifiable factors contributing to low HRQOL. Supplemental digital content is available in the text.