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Whether the new chronic kidney disease-epidemiology (CKD-EPI) equation without the race variable remains accurate enough for glomerular filtration rate (GFR) estimation in non-US kidney transplant recipients (KTRs) is unclear. We sought to compare the predictive performance between this equation and the classical CKD-EPI equation in a French cohort of KTRs. We also evaluated the performance of the European Kidney Function Consortium (EKFC) equation, an estimate that has proved very accurate in nontransplant patients and that does not include race variable.We retrospectively selected 489 KTRs for whom GFR was measured by inulin clearance. Performances of GFR equations were compared according to median bias, imprecision, and accuracy within 30% (P30) and 20% (P20). Differences in P20/P30 were tested using the exact McNemar test.Although the 4 equations exhibited a similar level of imprecision, the bias of the new CKD-EPI equation was +5.5 (4.0; 6.6) mL/min/1.73 m², much higher than the bias of the classical CKD-EPI, EKFC, and Modified Diet in Renal Diseases (MDRD) equation (2.4 [1.7;3.5], 2.2 [1.1;3.1], and -0.5 [-1.5; 1.0] mL/min/1.73 m², respectively). The new CKD-EPI equation was significantly less accurate with a P30 of 68.3% as compared with 74.2%, 75.3%, and 77.1% for the classical CKD-EPI, EKFC, and MDRD equation, respectively. The EKFC equation outperformed both versions of the CKD-EPI equation in terms of P20.The new CKD-EPI equation is suboptimal for the care and follow-up of European transplanted patients. The EKFC equation shows at least a similar performance to the MDRD and the classical CKD-EPI equation. Further validation of the EKFC equation in KTRs from a diverse ethnic background is needed.

Resume Le cancer de prostate est considere comme une tumeur « hormonodependante ». L’inhibition de l’action pro-tumorale de la testosterone a rapidement trouve sa place dans la prise en charge des cancers de prostate metastatiques, puis s’est imposee aussi dans les cancers localises. Pour tirer profit de l’action locale de la radiotherapie et de l’action systemique de l’hormonotherapie, de nombreuses etudes ont montre un benefice clinique majeur, demontrant meme une action synergique a l’association des deux traitements. La radiotherapie associee a de l’hormonotherapie par analogues de la LH-RH represente a present un traitement de reference dans les cancers de prostate localises de risque intermediaire et de haut risque, en tirant profit de l’action directe de l’hormonotherapie contre les cellules tumorales, mais egalement de son action radiosensibilisante. Cet article fait le point sur les benefices cliniques de l’association radiohormonale et les mecanismes de cette action synergique, et developpe les perspectives que vont offrir prochainement les nouvelles molecules d’hormonotherapie.

Objective To compare the performance of a newly developed race-free kidney recipient specific glomerular filtration rate (GFR) equation with the three current main equations for measuring GFR in kidney transplant recipients. Design Development and validation study Setting 17 cohorts in Europe, the United States, and Australia (14 transplant centres, three clinical trials). Participants 15 489 adults (3622 in development cohort (Necker, Saint Louis, and Toulouse hospitals, France), 11 867 in multiple external validation cohorts) who received kidney transplants between 1 January 2000 and 1 January 2021. Main outcome measure The main outcome measure was GFR, measured according to local practice. Performance of the GFR equations was assessed using P 30 (proportion of estimated GFR (eGFR) within 30% of measured GFR (mGFR)) and correct classification (agreement between eGFR and mGFR according to GFR stages). The race-free equation, based on creatinine level, age, and sex, was developed using additive and multiplicative linear regressions, and its performance was compared with the three current main GFR equations: Modification of Diet in Renal Disease (MDRD) equation, Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) 2009 equation, and race-free CKD-EPI 2021 equation. Results The study included 15 489 participants, with 50 464 mGFR and eGFR values. The mean GFR was 53.18 mL/min/1.73m 2 (SD 17.23) in the development cohort and 55.90 mL/min/1.73m 2 (19.69) in the external validation cohorts. Among the current GFR equations, the race-free CKD-EPI 2021 equation showed the lowest performance compared with the MDRD and CKD-EPI 2009 equations. When race was included in the kidney recipient specific GFR equation, performance did not increase. The race-free kidney recipient specific GFR equation showed significantly improved performance compared with the race-free CKD-EPI 2021 equation and performed well in the external validation cohorts (P 30 ranging from 73.0% to 91.3%). The race-free kidney recipient specific GFR equation performed well in several subpopulations of kidney transplant recipients stratified by race (P 30 73.0-91.3%), sex (72.7-91.4%), age (70.3-92.0%), body mass index (64.5-100%), donor type (58.5-92.9%), donor age (68.3-94.3%), treatment (78.5-85.2%), creatinine level (72.8-91.3%), GFR measurement method (73.0-91.3%), and timing of GFR measurement post-transplant (72.9-95.5%). An online application was developed that estimates GFR based on recipient’s creatinine level, age, and sex ( https://transplant-prediction-system.shinyapps.io/eGFR_equation_KTX/ ). Conclusion A new race-free kidney recipient specific GFR equation was developed and validated using multiple, large, international cohorts of kidney transplant recipients. The equation showed high accuracy and outperformed the race-free CKD-EPI 2021 equation that was developed in individuals with native kidneys. Trial registration ClinicalTrials.gov NCT05229939 .

PurposeIn this work, we addressed fully automatic determination of tumor functional uptake from positron emission tomography (PET) images without relying on other image modalities or additional prior constraints, in the context of multicenter images with heterogeneous characteristics.MethodsIn cervical cancer, an additional challenge is the location of the tumor uptake near or even stuck to the bladder. PET datasets of 232 patients from five institutions were exploited. To avoid unreliable manual delineations, the ground truth was generated with a semi-automated approach: a volume containing the tumor and excluding the bladder was first manually determined, then a well-validated, semi-automated approach relying on the Fuzzy locally Adaptive Bayesian (FLAB) algorithm was applied to generate the ground truth. Our model built on the U-Net architecture incorporates residual blocks with concurrent spatial squeeze and excitation modules, as well as learnable non-linear downsampling and upsampling blocks. Experiments relied on cross-validation (four institutions for training and validation, and the fifth for testing).ResultsThe model achieved good Dice similarity coefficient (DSC) with little variability across institutions (0.80 ± 0.03), with higher recall (0.90 ± 0.05) than precision (0.75 ± 0.05) and improved results over the standard U-Net (DSC 0.77 ± 0.05, recall 0.87 ± 0.02, precision 0.74 ± 0.08). Both vastly outperformed a fixed threshold at 40% of SUVmax (DSC 0.33 ± 0.15, recall 0.52 ± 0.17, precision 0.30 ± 0.16). In all cases, the model could determine the tumor uptake without including the bladder. Neither shape priors nor anatomical information was required to achieve efficient training.ConclusionThe proposed method could facilitate the deployment of a fully automated radiomics pipeline in such a challenging multicenter context.

BACKGROUND AND AIMS In renal transplantation, death with a functioning graft remains one of the main causes of graft loss. In the general population, renal function impairment is strongly associated with cardiovascular and all-cause mortality. Whether this association holds true for kidney transplant recipients (KTR) is unclear. This uncertainty is likely to be due, in part, to the fact that glomerular filtration rate (GFR) estimation based on serum creatinine (SCr) does not always provide an accurate evaluation of the graft function in KTR. As compared to SCr, we have previously shown in a large cohort of KTR that serum cystatin C (SCysC) is a much better marker of GFR. Herein, we sought to study the ability of the 1-year-post-transplant renal function to predict all-cause mortality according to the methods used to assess GFR. METHOD Four hundred and ten consecutive KTR for whom a measurement of GFR by inulin clearance was available at 1 year post-transplant were included. SCr and ScysC were measured with standardized methods. The association of the 1-year inulin clearance value the 1-year MDRD Study equation value and the 1-year CKD-EPI ScysC equation value with all-cause mortality was studied by ROC analysis and Cox model. RESULTS During a median follow-up of 17 years, 131 KTR died. Mean (±SD) inulin clearance at 1-year-post-transplant was 47 (±13) mL/min/1.73 m2. Areas under the ROC curves were similar for inulin and CKD-EPI ScysC equation values (0.62 for both), and were both significantly superior to that of the MDRD equation (0.54, P CONCLUSION We conclude that ScysC-based GFR estimation might better predict KTR outcome as compared with a traditional SCr-based estimation. The one year-post transplant GFR value given by the CKD-EPI ScysC equation should be further evaluated as a potential surrogate marker for both graft and patient survival.

BACKGROUND AND AIMS Current Glomerular filtration rate (GFR) estimating equations based on serum creatinine are facing increased criticism due to the inclusion of a race correction in black Americans with the CKD-EPI equation (CKD-EPIASR, A = Age, S = Sex, R = Race). New equations without race (CKD-EPIAS) has been proposed with creatinine and/or cystatin C. These equations were developed mainly from US cohorts with few renal transplanted patients. In the current analysis, we compared these new equations, notably with the new European Kidney Function Consortium (EKFC) equation. METHOD In this retrospective analysis, 489 transplanted patients from the University Hospital of Saint-Etienne were included. All subjects were white. GFR was measured with inulin or iohexol clearances. IDMS creatinine and standardized cystatin C results were available. Median bias (eGFR—mGFR), imprecision (interquartile range: IQR), and P30 accuracy (percentage of eGFR-values within ± 30% of mGFR) were calculated. RESULTS Among creatinine-based equations, the bias were 2.3, 5.5 and 2.2 mL/min/1.73 m² for the CKD-EPIASR, CKD-EPIAS and EKFC, respectively. IQRs were 16.1, 16.2 and 15.3 mL/min/1.73 m², respectively. P30 were 74.2, 68.3 and 75.3%, respectively. Among cystatin C-based equations, the bias were −3.1 and 0.8 mL/min/1.73 m² for the CKD-EPICC and the EKFCCC, respectively. IQRs were 13.7 and 13.4 mL/min/1.73 m², respectively. P30 were 78.5 and 81.4%, respectively. Among equations combining creatinine and CC, the bias were −1.3, 0.5 and 1.6 mL/min/1.73 m² for the CKD-EPIASR-CC, CKD-EPIAS-CC and EKFCcreatCC, respectively. IQRs were 12.7, 12.4 and 12.1 mL/min/1.73 m², respectively. P30 were 84.5, 82.6 and 80.6%, respectively. CONCLUSION In our cohort of European transplanted patients, both the EKFCcreat and CKD-EPIASR equations performed better than the new CKD_EPIAS. Compared with creatinine-based equations, the new EKFCCC equation and all combined equations performed better. Cystatin C-based equations have the advantage to be accurate without any race variable.

What are the mechanisms responsible for spontaneous cospeech gesture production? Driven by the close connection between cospeech gestures and object-related actions, recent research suggests that cospeech gestures originate in perceptual and motoric simulations that occur while speakers process information for speaking (Hostetter & Alibali, 2008). Here, we test this claim by highlighting object affordances during a communication task, inspired by the classic stimulus-response compatibility paradigm by Tucker and Ellis (1998). We compared cospeech gestures in situations where target objects were oriented toward the speakers' dominant hand (grasping potential enhanced), with situations where they were oriented toward the nondominant hand. Before the main experiment, we conducted a replication attempt of Tucker and Ellis' (1998: Experiment 1) to (re)establish the effect of stimulus compatibility, using contemporary items. Contrary to expectations, we could not replicate the original findings. Furthermore, compatibly with our replication results, the gesture data showed that enhancing grasping potential did not increase the amount of cospeech gestures produced. Vertical orientation nevertheless did, with upright objects eliciting more cospeech gestures than inverted ones, which does suggest a relation between affordance and gesture production. Our results challenge the automaticity of affordance effects, both in a classic stimulus-response compatibility experiment as well as in a more interactive dialogue setting and suggest that previous findings on cospeech gestures emerge from thinking and communicating about action-evoking content rather than from the affordance-compatibility of the presented objects. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

BackgroundIntensity modulated radiation therapy (IMRT) combined with androgen deprivation therapy (ADT) has become the standard treatment for patients with high-risk prostate cancer. Two techniques of rotational IMRT are commonly used in this indication: Volumetric Modulated Arc Therapy (VMAT) and helical tomotherapy (HT). To the best of our knowledge, no study has compared their related costs and clinical effectiveness and/or toxicity in prostate cancer. We aimed to assess differences in costs and toxicity between VMAT and HT in patients with high-risk prostate cancer with pelvic irradiation.Material and MethodsWe used data from the “RCMI pelvis” prospective multicenter study (NCT01325961) including 155 patients. We used a micro-costing methodology to identify cost differences between VMAT and HT. To assess the effects of the two techniques on total actual costs per patient and on toxicity we used stabilized inverse probability of treatment weighting.ResultsThe mean total cost for HT, €2019 3,069 (95% CI, 2,885–3,285) was significantly higher than the mean cost for VMAT €2019 2,544 (95% CI, 2,443–2,651) (p ConclusionUse of VMAT was associated with lower costs for IMRT planning and treatment than HT. Similar stabilized long-term toxicity was reported in both groups after higher acute GI and GU toxicity in VMAT. The estimates provided can benefit future modeling work like cost-effectiveness analysis.

Machine learning techniques are becoming increasingly popular in radiomics studies. They can handle high dimensional sets of radiomics features with higher robustness than usual statistical analyses, by capturing complex interactions between features themselves and between feature combinations and clinical endpoints under investigation in order to build efficient prognostic/predictive models. However, there is no “one fits all” solution and deciding which algorithm is the most accurate for a given application is not always straightforward. In this paper, to keep a realistic perspective on various emerging clinical applications based on radiomics, we performed an evaluation of the popular random forest classifier for predicting local failure in cervix cancer exploiting identical data, but relying on different methodologies to select and combine features of interest. The main objective was to demonstrate various challenges of model building and tuning for radiomics applications. The results obtained in the present work could provide general guidelines to assist in the practical development of radiomics-based models.

Immunotherapy occupies a growing place in urologic oncology, mainly for kidney and bladder cancers. On the basis of encouraging preclinical work, the combination of immunotherapy with radiotherapy aims to increase the tumor response, including in metastatic tumors, which raises many hopes, which this article reviews., L’immunothérapie occupe une place grandissante en cancérologie urologique, principalement pour les cancers du rein et de la vessie. Sur la base de travaux précliniques encourageants, la combinaison de l’immunothérapie avec la radiothérapie ambitionne de majorer la réponse tumorale, y compris des tumeurs métastatiques ce qui suscite de nombreux espoirs dont cet article fait le bilan.

Personalized medicine aims at offering optimized treatment options and improved survival for cancer patients based on individual variability. The success of precision medicine depends on robust biomarkers. Recently, the requirement for improved non-biologic biomarkers that reflect tumor biology has emerged and there has been a growing interest in the automatic extraction of quantitative features from medical images, denoted as radiomics. Radiomics as a methodological approach can be applied to any image and most studies have focused on PET, CT, ultrasound, and MRI. Here, we aim to present an overview of the radiomics workflow as well as the major challenges with special emphasis on the use of multiparametric MRI datasets. We then reviewed recent studies on radiomics in the field of pelvic oncology including prostate, cervical, and colorectal cancer.

The aim of this retrospective multicentric study was to develop and evaluate a prognostic

Introduction. The effects of long-term stretching (>6 months) in hemiparesis are unknown. This prospective, randomized, single-blind controlled trial compared changes in architectural and clinical parameters in plantar flexors of individuals with chronic hemiparesis following a 1-year guided self-stretch program, compared with conventional rehabilitation alone. Methods. Adults with chronic stroke-induced hemiparesis (time since lesion >1 year) were randomized into 1 of 2, 1-year rehabilitation programs: conventional therapy (CONV) supplemented with the Guided Self-rehabilitation Contract (GSC) program, or CONV alone. In the GSC group, specific lower limb muscles, including plantar flexors, were identified for a diary-based treatment utilizing daily, high-load, home self-stretching. Blinded assessments included (1) ultrasonographic measurements of soleus and medial gastrocnemius (MG) fascicle length and thickness, with change in soleus fascicle length as primary outcome; (2) maximum passive muscle extensibility (XV1, Tardieu Scale); (3) 10-m maximal barefoot ambulation speed. Results. In all, 23 individuals (10 women; mean age [SD], 56 [±12] years; time since lesion, 9 [±8] years) were randomized into either the CONV (n = 11) or GSC (n = 12) group. After 1 year, all significant between-group differences favored the GSC group: soleus fascicle length, +18.1mm [9.3; 29.9]; MG fascicle length, +6.3mm [3.5; 9.1]; soleus thickness, +4.8mm [3.0; 7.7]; XV1 soleus, +4.1° [3.1; 7.2]; XV1 gastrocnemius, +7.0° [2.1; 11.9]; and ambulation speed, +0.07m/s [+0.02; +0.16]. Conclusions. In chronic hemiparesis, daily self-stretch of the soleus and gastrocnemius over 1 year using GSC combined with conventional rehabilitation increased muscle fascicle length, extensibility, and ambulation speed more than conventional rehabilitation alone.

Past research has sought to elucidate how speakers and addressees establish common ground in conversation, yet few studies have focused on how visual cues such as co-speech gestures contribute to this process. Likewise, the effect of cognitive constraints on multimodal grounding remains to be established. This study addresses the relationship between the verbal and gestural modalities during grounding in referential communication. We report data from a collaborative task where repeated references were elicited, and a time constraint was imposed to increase cognitive load. Our results reveal no differential effects of repetition or cognitive load on the semantic-based gesture rate, suggesting that representational gestures and speech are closely coordinated during grounding. However, gestures and speech differed in their execution, especially under time pressure. We argue that speech and gesture are two complementary streams that might be planned in conjunction but that unfold independently in later stages of language production, with speakers emphasizing the form of their gestures, but not of their words, to better meet the goals of the collaborative task.A collaborative referencing task is used to examine communication through both verbal and visual modalities in order to understand the cognitive constraints on multimodal grounding in conversation. Analyses of co-speech gesture show that while gesture and speech might be planned in conjunction, that they unfold independently in language production.

Hand gestures are tightly coupled with speech and with action. Hence, recent accounts have emphasised the idea that simulations of spatio-motoric imagery underlie the production of co-speech gestures. In this study, we suggest that action simulations directly influence the iconic strategies used by speakers to translate aspects of their mental representations into gesture. Using a classic referential paradigm, we investigate how speakers respond gesturally to the affordances of objects, by comparing the effects of describing objects that afford action performance (such as tools) and those that do not, on gesture production. Our results suggest that affordances play a key role in determining the amount of representational (but not non-representational) gestures produced by speakers, and the techniques chosen to depict such objects. To our knowledge, this is the first study to systematically show a connection between object characteristics and representation techniques in spontaneous gesture production during the depiction of static referents.

Le but de cette etude etait d’evaluer la reproductibilite d’un protocole utilisant des capteurs inertiels afin de caracteriser les mouvements primaires et associes de la tete. Vingt-deux sujets sains ont ete evalues deux fois a trois jours d’intervalle dans les memes conditions experimentales. Deux capteurs inertiels ont permis l’evaluation de l’amplitude articulaire de la tete. Trois cycles de mouvements complets dans chaque plan ont ete realises. Un sujet atteint de dystonie cervicale a egalement ete evalue a l’aide du meme protocole avant et apres exercices d’auto-reeducation. Les resultats montrent que toutes les amplitudes sont reproductibles sauf pour les mouvements associes dans le plan sagittal. Ensuite, notre protocole a permis d’observer une amelioration de la cinematique de la tete apres les exercices d’auto-reeducation effectues par le patient. Ces resultats montrent la fiabilite des capteurs inertiels comme outils d’evaluation des mouvements de la tete, une evolution de la methode proposee permettra une generalisation aux mouvements cervicaux.

Radiation recall is a rare phenomenon, defined as an acute inflammatory reaction in a previously irradiated area, after administration of anti-tumor agents, including chemotherapy. It is most commonly reported to trigger skin reactions but internal organ involvement is possible, particularly with gemcitabine. We report here a unique case of a gemcitabine-induced radiation recall myelitis following spinal irradiation. A 53-year-old patient received analgesic irradiation of the seventh thoracic vertebra (T7) in the context of metastatic non-small cell lung cancer, at conventional radiotherapy dose and fractionation. She was subsequently treated with gemcitabine and developed myelitis whose chronology is compatible with a radiation recall reaction. Spinal MRI confirmed a T6–T7 spinal cord enhancement, with an associated spinal cord oedema. Corticosteroids and supportive care did not improve myelitis symptoms. The patient died within a year of the radiation recall, due to a metastatic progression of lung cancer. This is, to our knowledge, the first reported case of gemcitabine-induced radiation recall myelitis and only the third case involving the spinal cord. Radiation recall is a rare and poorly understood phenomenon and all cases should be reported.

The aim of this study was to validate previously developed radiomics models relying on just two radiomics features from 18F-fluorodeoxyglucose positron emission tomography (PET) and magnetic resonance imaging (MRI) images for prediction of disease free survival (DFS) and locoregional control (LRC) in locally advanced cervical cancer (LACC). Patients with LACC receiving chemoradiotherapy were enrolled in two French and one Canadian center. Pre-treatment imaging was performed for each patient. Multicentric harmonization of the two radiomics features was performed with the ComBat method. The models for DFS (using the feature from apparent diffusion coefficient (ADC) MRI) and LRC (adding one PET feature to the DFS model) were tuned using one of the French cohorts (n = 112) and applied to the other French (n = 50) and the Canadian (n = 28) external validation cohorts. The DFS model reached an accuracy of 90% (95% CI [79–98%]) (sensitivity 92–93%, specificity 87–89%) in both the French and the Canadian cohorts. The LRC model reached an accuracy of 98% (95% CI [90–99%]) (sensitivity 86%, specificity 100%) in the French cohort and 96% (95% CI [80–99%]) (sensitivity 83%, specificity 100%) in the Canadian cohort. Accuracy was significantly lower without ComBat harmonization (82–85% and 71–86% for DFS and LRC, respectively). The best prediction using standard clinical variables was 56–60% only. The previously developed PET/MRI radiomics predictive models were successfully validated in two independent external cohorts. A proposed flowchart for improved management of patients based on these models should now be confirmed in future larger prospective studies.

In face-to-face communication, speakers typically integrate information acquired through different sources, including what they see and what they know, into their communicative messages. In this study, we asked how these different input sources influence the frequency and type of iconic gestures produced by speakers during a communication task, under two degrees of task complexity. Specifically, we investigated whether speakers gestured differently when they had to describe an object presented to them as an image or as a written word (input modality) and, additionally, when they were allowed to explicitly name the object or not (task complexity). Our results show that speakers produced more gestures when they attended to a picture. Further, speakers more often gesturally depicted shape information when attended to an image, and they demonstrated the function of an object more often when they attended to a word. However, when we increased the complexity of the task by forbidding speakers to name the target objects, these patterns disappeared, suggesting that speakers may have strategically adapted their use of iconic strategies to better meet the task’s goals. Our study also revealed (independent) effects of object manipulability on the type of gestures produced by speakers and, in general, it highlighted a predominance of molding and handling gestures. These gestures may reflect stronger motoric and haptic simulations, lending support to activation-based gesture production accounts.

Activation of complement through the alternative pathway has a key role in the pathogenesis of IgA nephropathy (IgAN). Large, international, genome-wide association studies have shown that deletion of complement factor H–related genes 1 and 3 (CFHR3,1Δ) is associated with a reduced risk of developing IgAN, although the prognostic value of these deletions in IgAN remains unknown. Here, we compared the renal outcomes of patients with IgAN according to their CFHR3,1Δ genotype. This retrospective, monocentric cohort study included 639 white patients with biopsy-proven IgAN since 1979 (mean age at diagnosis, 40.1 years; median follow-up, 132 months). We determined the number of CFHR3 and CFHR1 gene copies by quantitative PCR and collected clinical and biologic data by reviewing the patients’ medical records. In all, 30.5% of the patients were heterozygous and 4% were homozygous for CFHR3,1Δ. We did not detect an association between CFHR3,1Δ and age, eGFR, urinary protein excretion rate, or the presence of hypertension or hematuria at the time of diagnosis. The mean intensities of immune IgA, IgG, and C3 deposits were lower in the group with heterozygous or homozygous gene deletions than in those with no deletion. However, CFHR3,1Δ did not associate with progression to stage 3 CKD or renal death. In conclusion, the CFHR3,1Δ genotype did not associate with progression toward CKD stages 3 and 5 in our white population of patients with IgAN, although it did associate with a reduced level of glomerular immune deposits.

Introduction et but de l’etude L’objectif de cette etude etait de developper et d’evaluer une signature radiomique en utilisant l’imagerie tomographique par emission de positons (TEP/TDM) chez des patients atteints d’un cancer du poumon non a petites cellules traites par irradiation stereotaxique. Materiel et methodes Il s’agit d’une etude retrospective multicentrique portant sur 87 patients atteints d’un atteints d’un cancer du poumon non a petites cellules de stade T1-T2 traite dans quatre centres du Grand Ouest. Les patients des trois premiers centres (n = 27, 29 et 8) constituaient le groupe d’apprentissage, et ceux du quatrieme (n = 23) le groupe de validation. Le critere d’evaluation principal etait le controle local. En tout, 184 parametres radiomiques ont ete extraits (92 de chaque modalite) et sept parametres cliniques, histologiques et therapeutiques ont ete consideres. En raison des differents scanographes et protocoles d’acquisition des institutions, nous avons utilise la methode ComBat pour harmoniser les parametres de texture. Resultats et analyse statistique En analyse unifactorielle, deux parametres issus de la TEP et deux de la scanographie etaient significativement predictifs du controle local, a l’inverse des variables cliniques. Le meilleur modele predictif du groupe d’apprentissage etait obtenu en associant deux parametres TEP (IC2 et strength), avec une sensibilite de 100 % et une specificite de 88 %, et un hazard ratio indefini (p Conclusion Notre etude a permis d’identifier deux parametres de textures derives de la TEP/scanographie comme facteurs predictifs independants associes a la recidive locale chez les patients atteints d’un cancer du poumon non a petites cellules traites par irradiation stereotaxique. Ce modele merite d’etre confirme sur une cohorte plus consequente et pourrait etre utilise en clinique pour guider une eventuelle escalade de dose.

This paper deals with a stochastic approach based on the principle of the maximum entropy to investigate the effect of the parameter random uncertainties on the arterial pressure. Motivated by a hyperelastic, anisotropic, and incompressible constitutive law with fiber families, the uncertain parameters describing the mechanical behavior are considered. Based on the available information, the probability density functions are attributed to every random variable to describe the dispersion of the model parameters. Numerous realizations are carried out, and the corresponding arterial pressure results are compared with the human non-invasive clinical data recorded over a mean cardiac cycle. Furthermore, the Monte Carlo simulations are performed, the convergence of the probabilistic model is proven. The different realizations are useful to define a reliable confidence region, in which the probability to have a realization is equal to 95%. It is shown through the obtained results that the error in the estimation of the arterial pressure can reach 35% when the estimation of the model parameters is subjected to an uncertainty ratio of 5%. Finally, a sensitivity analysis is performed to identify the constitutive law relevant parameters for better understanding and characterization of the arterial wall mechanical behaviors.

A new protocol for cryopreservation of arteries frozen at −80°C was compared to the reference protocol for cryopreservation at −150°C and to freshly harvested arteries. The aim of the study is to evaluate both protocols as global procedures to freeze and thaw arteries commonly used in tissue banks. Changes in mechanical properties of rabbit common carotid arteries were studied. Vascular segments were tested in vitro under dynamics loading conditions. Pressure and diameter were recorded simultaneously by a high fidelity transducer and an echotracking device, respectively. The pressure–diameter relationship was fitted by the arctangent Langewouters' model and the arterial thickness was derived from histological measurements. Histological sections showed that the fresh and −80°C groups were less damaged by hemodynamic load and histological preparation than the −150°C group ( p

The aim of this paper is to illustrate the application of a stochastic approach to estimate the human common carotid arterial pressure. The analysis took into account the possible random uncertainties of the problem inputs such as geometric information and mechanical model parameters so that it is called a probabilistic parametric approach. Based on the only available information reported in literature, entropy maximum principle was used to develop probabilistic density functions for every random variable. In addition, in vivo human experimental data were considered for the determination of the so-called mean or deterministic model. Furthermore, numerical simulations of Monte Carlo were carried out involving the dispersion of all the uncertain parameters. Results showed that uncertainty of 5% led to error up to 20% in the arterial pressure estimation. Convergence was proved and a region with a confidence probability of 95% was constructed to allow the prediction of the random response of the arterial pressure. Eventually, we managed numerous calculations to analyze the influence of each random variable of the problem inputs over the arterial pressure evolution.

Severe lupus nephritis in the absence of systemic lupus erythematosus (SLE) is a rare condition with an unclear clinical presentation and outcome. We conducted a historical observational study of 12 adult (age >18 years) patients with biopsy-proven severe lupus nephritis or lupus-like nephritis without SLE immunological markers at diagnosis or during follow-up. Excluded were patients with chronic infections with HIV or hepatitis B or C; patients with a bacterial infectious disease; and patients with pure membranous nephropathy. Electron microscopy was retrospectively performed when the material was available. End points were the proportion of patients with a complete response (urine protein to creatinine ratio

Objective The effects of long-term (> 6 months) stretching in spastic paresis are unknown. The objective of this study was to compare the architectural and clinical changes in plantar flexors in patients with chronic hemiparesis following a one-year daily self-stretch program vs. standard rehabilitation. Material/patients and methods Twenty-three patients with chronic hemiparesis (8 W; mean age, 56 [12]; time since lesion 9 [8]) participated in a one-year randomized controlled trial involving either conventional therapy (CONV) or a daily self-stretch program within a Guided Self-rehabilitation Contract (GSC). Assessments involved: (i) soleus and medial gastrocnemius (MG) fascicle length, pennation angle, thickness, tendon length, measured by ultrasonography; (ii) XV1, angle of arrest at slow stretch in soleus (XV1SOL), gastro-soleus complex (XV1GAS), gluteus maximus (XV1GM) and rectus femoris (XV1RF); (iii) 10-meter maximal ambulation speed. Correlations (Pearson's) between architectural parameters and XV1 were also explored. Results After one year, soleus fascicle length increased by +16.6 mm (CI95 [+10.3; +22.9]; +42%), in the GSC group vs. −0.1 mm (CI95 [−7.3; +7.1]; −3.7%), in the CONV group (P = 0.005, Rank-Ancova), MG fascicle length increased by +5.2 mm (CI95 [+2.75; +7.65]; +13%), in the GSC group vs. +1.2 mm (CI95 [−2.0; +4.4]; +7%), in the CONV group (P = 0.01), soleus thickness increased by +4.3 mm (CI95 [+2.7; +5.9]; +33%), vs. −0.3 mm (CI95 [−2.4; +1.8]; −0.8%), in the CONV group (P = 0.005). Changes in XV1 involved XV1SOL, +2.4° (CI95 [+0.9; +4.0]; +2.4%), in the GSC group vs. +0.1° (CI95 [−2.7; +2.8]; +0.1%), in the CONV group (P = 6.9 E-05); XV1GAS, +7.4° (CI95[+5.0; +9.8]; +8%) vs. +1.5° (CI95 [−3.3; +6.3]; +1.5%; P = 0.003); XV1GM, +5.3° (CI95[+2.7; + 7.9]; 4.2%) vs. +1.5° (CI95[+0.1; +5.4]; +1.2%; P = 0.025); XV1RF, +10.5° (CI95 [+5.8; + 16.4]; +3.4%) vs. +1.5° (CI95 [−3.75; +6.65]; +1.9%; P = 0.08). Walking speed increased by +0.08 m/s (CI95 [+0.04; +0.12]; +14%, P = 0.006, t-test) in the GSC group vs. +0.04 m/s (CI95[0.0; +0.08]; +5%, NS) in the CONV group. At baseline, XV1SOL correlated negatively with soleus tendon length (R = −0.74, P = 0.0003) and positively with muscle thickness (R = 0.68, P = 0.015). Discussion – conclusion In patients with chronic hemiparesis, a daily self-stretch program of soleus and medial gastrocnemius through Guided Self-rehabilitation Contract over one year increased muscle fascicle length and thickness more than conventional rehabilitation.

Introduction L’hyperparathyroidie primaire est une pathologie habituellement benigne et de decouverte fortuite. L’hypercalcemie peut toutefois se compliquer de troubles du rythme cardiaque graves, surtout si des anomalies de la kaliemie s’y ajoutent. Nous rapportons une observation d’arret cardiaque par fibrillation ventriculaire chez une patiente de 53 ans atteinte d’une hyperparathyroidie primaire avec hypercalcemie majeure compliquee d’acidose tubulaire distale avec hypokaliemie, d’issue heureusement favorable. Observation Une femme de 53 aux antecedents de troubles fonctionnels intestinaux, porteuse d’une lithisase renale non compliquee, etait vue en endocrinologie en janvier 2014 pour la decouverte d’une hypercalcemie (3,21 mmol/L) avec hypophosphoremie (0,56 mmol/L). Le controle biologique confirmait l’hyperparathyroidie primaire (calcemie a 3,44 mmol/L, PTH a 298 ng/L, N : 15–57). La fonction renale etait normale (clearance a 129 mL/min), la calciurie elevee a 500 mg/L, la kaliemie n’etait pas dosee (derniere kaliemie connue, 4 ans plus tot, a 3.6 mmol/L). L’osteodensitometrie etait en faveur d’une osteopenie lombaire. L’echographie cervicale montrait un volumineux nodule lobaire gauche heterogene de 30 mm de diametre, interprete comme thyroidien, mais situe en regard d’une fixation parathyroidienne intense sur la scintigraphie au MIBI. L’intervention etait refusee par la patiente, et 6 mois plus tard, la calcemie etait a 2,9 mmol/L. Les troubles intestinaux et le syndrome polyuro-polydipsique s’aggravaient au cours des mois suivants. En janvier 2015, de facon contemporaine a un syndrome grippal, survenait un arret cardio-circulatoire par fibrillation ventriculaire. Les manœuvres de reanimation immediatement mises en œuvre etaient efficaces. La coronarographie realisee en urgence etait strictement normale. Le bilan d’entree en reanimation objectivait une calcemie a 3 mmol/L, une kaliemie a 2.5 mmol/L et une acidose lactique. La phosphoremie etait basse (0.55 mmol/L), la magnesemie normale, la creatininemie a 90 μmol/L, la PTH a 800 ng/L. L’hypokaliemie necessitait un apport massif de potassium, temoignant d’une hypokalicytie majeure, alors que la calcemie etait corrigee par hydradation, bisphosphonates et calcitonine. Les explorations renales permettaient de rapporter l’hypokaliemie a une probable acidose tubulaire distale (hyperchloremie, trou anionique plasmatique normal, trou anionique urinaire a 38 mmol/L, pH urinaire inadapte). L’evolution etait finalement favorable et sans sequelles. La reascension rapide de la calcemie a la sortie de reanimation conduisait a une chirurgie en urgence d’ablation de la volumineuse tumeur kystique de la parathyroide inferieure gauche adherant a la thyroide, necessitant une lobo-isthmectomie gauche. L’histologie confirmait l’adenome parathyroidien sans signes patents de malignite. A j7 de la chirurgie, le bilan ionique etait normalise. Discussion L’hyperparathyroidie primaire peut se compliquer, meme en l’absence de nephrocalcinose, d’acidose tubulaire distale avec hypokaliemie profonde, conduisant a un risque eleve de troubles du rythme cardiaque [1] , [2] . L’acidose tubulaire renale de type 1 est une acidose metabolique hyperchloremique (trou anionique plasmatique normal) a reponse renale inadaptee (trou anionique urinaire eleve suggerant un defaut d’elimination acide avec ammoniurie effondree). Le test d’alcalinisation des urines, ici non realise, est en theorie necessaire pour differencier une tubulopathie proximale d’une tubulopathie distale [3] . Les crises parathyroidiennes surviennent volontiers chez des patients porteurs de volumineux adenomes ou carcinomes parathyroidiens kystiques. Chez cette patiente, l’indication operatoire etait formelle compte tenu entre autres de l’âge, de la severite de l’hypercalcemie, de l’hypercalciurie majeure, et de la taille de l’adenome parathyroidien ainsi que de la valeur de la PTH qui faisaient craindre un carcinome parathyroidien. Conclusion En cas d’hyperparathyroidie primaire, il est imperatif de doser la kaliemie, afin de depister un risque accru de troubles du rythme cardiaque.

Objective To explore changes in muscle architectural parameters of the muscle-tendon unit of soleus and medial gastrocnemius (GM) in patients with chronic hemiparesis, after 1 year of rehabilitation. Material/Patients and methods In this prospective study, 20 chronic hemiparetic patients (8 W, mean age: 56 [12], time since lesion 9 [8]) were evaluated. Muscle architectural parameters including muscle fascicle length, pennation angle, thickness, tendon and muscle belly lengths were evaluated in vivo using ultrasonography in passive condition (verified by electromyographic recording) in a seated patient with ankle, knee and hip on the paretic side at 90°. Following the biomechanical analysis, each patient benefited from the Five Step Assessment (FSA), involving the measure of XV1, angle of arrest at slow and strong stretch, which estimates soft tissue extensibility around each muscle. Four muscles of interest in the lower limb were selected for this measure: soleus (XV1Sol), medial gastro-soleus complex (XV1GSC), gluteus maximus (XV1GM) and rectus femoris (XV1RF). Biomechanical and clinical analyses were performed at the beginning and after 1 year of treatment. Two treatments were implemented: – conventional rehabilitation (50%); – guided Self-rehabilitation contract (GSC, 50%). Patients in the GSC group were prescribed a daily self-stretch program with static (> 10 min/muscle/day) and eccentric stretch. Changes in architectural parameters and clinical muscle extensibility of overall patients before and after 1 year of rehabilitation were analyzed (Student's). Results After 1 year, muscle fascicle length and thickness increased respectively by 6.1 mm (14.2%, P = 0.05), 1.8 mm (13.6%, P = 0.06) in soleus, and by 2.9 mm (9.1%, P = 0.04) and 1.7 mm (13.2%, P = 0.03) in MG. Muscle belly length of MG increased by 2.9 cm (17%, P = 0.0001) and its tendon length decreased by 0.82 cm (5%, P = 0.04). XV1GSC increased by 4.8° (3.3%, P = 0.07), XV1GM by 4.1° (3.3%, P = 0.0004) and XV1RF by 7.2° (6%, P = 0.02). Discussion - Conclusion Stretch of soleus and medial gastrocnemius practiced over the long term in patients with spastic hemiparesis allowed structural changes, increasing muscle fascicle length and thickness. Muscle belly length of medial gastrocnemius also increased significantly while its tendon length decreased, suggesting that the tendon may adapt its length to the muscle length changes.

Objectives The purpose of this study was to correlate the arterial mechanics of carotid atherosclerotic plaques assessed from echotracking with their composition by high-resolution magnetic resonance imaging (HR-MRI). Background Analysis of the relationship between mechanical parameters and structure of the plaque allows better understanding of the mechanisms leading to mechanical fatigue of plaque material, plaque rupture, and ischemic events. A specific longitudinal gradient of strain (reduced strain, i.e., lower radial strain at the plaque level than at the adjacent segment) has been shown in atherosclerotic plaques on the common carotid artery (CCA) in patients with hypertension, dyslipidemia, or type 2 diabetes mellitus. The structural abnormalities underlying this functional behavior have not been determined. Methods Forty-six carotid plaques from 27 patients were evaluated; plaques were present at the site of the carotid bifurcation and extended to the CCA. Among the 27 patients, 9 had previous ischemic stroke ipsilateral to carotid stenosis (symptomatic) and 18 had not (asymptomatic). Mechanical parameters were measured at 128 sites on a 4-cm long CCA segment by noninvasive echotracking system, and strain gradient was calculated. Plaque composition was noninvasively determined by HR-MRI. Results Complex plaques at HR-MRI (i.e., American Heart Association [AHA] stages IV to VIII) more often displayed a reduced strain than the simple plaques (i.e., AHA stages I to III; p = 0.046). HR-MRI verified complex plaques were associated with an outer remodeling upon echotracking, and had a lower distensibility than adjacent CCA (17.0 ± 5.0 MPa−1 vs. 21.7 ± 7.3 MPa−1; p = 0.007). An outer remodeling was observed in plaques with a lipid core at HR-MRI and was more frequent in symptomatic carotids. Conclusions These findings indicate that the longitudinal mechanics of “complex” plaques follows a specific pattern of reduced strain. They also suggest that reduced strain, associated with an outer remodeling, may be a feature of high-risk plaques.

The goal of this study was to model the in vivo non-linear mechanical behavior of human common carotid arteries (CCAs) and then to compare wall stresses and associated contributions of micro-constituents in normotensive (NT) and treated hypertensive (HT) subjects. We used an established theoretical model of 3D arterial mechanics that assumes a hyperelastic, anisotropic, active–passive, and residually stressed wall. In vivo data were obtained non-invasively from CCAs in 16 NT (21–64 years old) and 25 treated HT (44–69 years old) subjects. The associated quasi-static boundary value problem was solved semi-analytically over a cardiac cycle while accounting for surrounding perivascular tissue. Best-fit values of model parameters, including those describing contributions by intramural elastin, fibrillar collagen, and vascular smooth muscle, were estimated by a non-linear least-squares method. The model (1) captured temporal changes in intraluminal pressure, (2) estimated wall stress fields that appeared to reflect the presence or absence of age and disease, and (3) suggested changes in mechanical characteristics of wall micro-constituents despite medical treatment of hypertension. For example, age was positively correlated with residual stresses and altered fibrillar collagen in NT subjects, which indirectly validated the modeling, and HT subjects had higher levels of stresses, increased smooth muscle tone, and a stiffer elastin-dominated matrix despite treatment. These results are consistent with prior reports on effects of age and hypertension, but provide increased insight into evolving contributions of cell and matrix mechanics to arterial behavior in vivo.

IntroductionAssocier les approches fonctionnelle et structurale améliore la valeur prédictive de la rupture de plaque et des évènements ischémiques. Deux types fonctionnels de contrainte de courbure ont été déterminés le long de l’artère carotide commune (ACC) (Paini et al. Stroke 2007; Beaussier et al. Hypertension 2008) : le type A (paroi avec plaque plus distensible que la paroi adjacente) et son contraire, le type B plus souvent observé chez les hypertendus essentiels.ObjectifCorréler les propriétés mécaniques à la composition d’une plaque d’athérosclérose au niveau de l’ACC.Méthode27 patients présentant une plaque d’athérosclérose sténosante sur l’ACC ont été inclus : 18 asymptomatiques (AS) et 9 symptomatiques (S, i.e. convalescents d’un accident vasculaire cérébral (AVC) homolatéral). Les paramètres mécaniques ont été mesurés par une nouvelle technique d’échotracking (Artlab®) sur 128 sites adjacents d’un segment d’ACC de 4cm. La composition de la plaque a été déterminée en imagerie par résonance magnétique (IRM). 46 ACC porteuses de plaque ont été analysées.RésultatsLe type B (25 plaques) serait (Chi2, P=0.054) plus souvent associé à un type de plaque complexe (i.e. stades AHA IV-VII), contrairement au type A (21 plaques). Les plaques homolatérales à l’AVC des patients S présentent un remodelage externe (P=0.06) (diamètre externe augmenté et diamètre interne inchangé) alors que les plaques des patients AS présentent un remodelage interne (P

The analysis of plaque mechanics along the longitudinal axis (bending strain) may provide useful information because repetitive bending strain of an atherosclerotic plaque can fatigue the wall material and result in plaque rupture. Whether essential hypertension is associated with a specific pattern of bending strain has not yet been determined. The study included 92 patients with an atherosclerotic plaque on the common carotid artery: 66 patients with essential hypertension, either treated or not, and 26 normotensive patients. A novel noninvasive echotracking system (ArtLab; Esaote, The Netherlands) was used to measure intima-media thickness, diameter, and distensibility at 128 sites on a 4-cm-long carotid segment. Carotid plaque was either less elastic than adjacent carotid artery (inward strain) or more elastic (outward strain). Inward strain was more frequently associated with an inward plaque remodeling, whereas an outward strain was more frequently associated with an outer remodeling. In multivariate logistic regression analysis, patients with essential hypertension were more likely to exhibit an inward strain of carotid plaque (odds ratio=6.9 [1.4 to 34.9]; P P P

A new protocol for cryopreservation of arteries frozen at -80 degrees C was compared to the reference protocol for cryopreservation at -150 degrees C and to freshly harvested arteries. The aim of the study is to evaluate both protocols as global procedures to freeze and thaw arteries commonly used in tissue banks. Changes in mechanical properties of rabbit common carotid arteries were studied. Vascular segments were tested in vitro under dynamics loading conditions. Pressure and diameter were recorded simultaneously by a high fidelity transducer and an echotracking device, respectively. The pressure-diameter relationship was fitted by the arctangent Langewouters' model and the arterial thickness was derived from histological measurements. Histological sections showed that the fresh and -80 degrees C groups were less damaged by hemodynamic load and histological preparation than the -150 degrees C group (p0.05). No differences between fresh and cryopreserved arteries regarding the structural (diameter, intimal-media thickness) and mechanical parameters (distensibility, circumferential stress, elastic modulus) were found. The isobaric circumferential stress was reduced in frozen arteries. These results demonstrate that the cryopreservation at -80 degrees C preserves the histological structure and mechanical properties better than the cryopreservation at -150 degrees C, suggesting that the new cryopreservation protocol at -80 degrees C is a method of choice for treating vessel replacement in vascular surgery.

International audience; This paper demonstrates the feasibility of material identification and wall stress computation for human common carotid arteries based on non-invasive in vivo clinical data:dynamical intraluminal pressure measured by applanation tonometry, and medical diameter and intimal-medial thickness measured by high-resolution ultrasound echotracking. The mechanical behavior was quantified assuming an axially pre-stretched thick-walled, cylindrical artery subjected to dynamical blood pressure and perivascular constraints. The wall was further assumed to be three-dimensional and to consist of a nolinear, hyperelastic, anisotropic, incompressible material with smooth muscle activity and residual stresses. Mechanical contributions by individual constituents - an elastin - dominated matrix, collagen fibers, and vascular smooth muscle- were accounted for using a previously proposed microstructurally motivated constitutive relatin. The in vivo boundary value problem was solved semi anlytically to compute the inner pressure during a mean cardiac cycle. Using a nonlinear least-squares method, optimal model parameters were determined by minimizing differences between computed and measured inner pressures over a mean cardiac cycle. The fit-to-data from two healthy patients was very good and the predicted radial, circumferential, and axial stretch and stress fields were sensible. Hence, the proposed approach was able to identify complex geometric and material parameters directly from non invasive in vivo human data.