Search

Background: In heart transplantation, antibody-mediated rejection (AMR) is a major contributor to patient morbidity and mortality. Multiple routine endomyocardial biopsies (EMB) remain the gold standard to detect AMR, but this invasive procedure suffers from many limitations. We aimed to develop and validate an AMR risk model to improve individual risk stratification of AMR. Methods: Heart recipients from 2 referral transplant centers, Cedars-Sinai (US) and Pitié-Salpêtrière (France), were included from 2012 to 2019. Database included detailed clinical, immunologic, imaging, and histological parameters. The US cohort was randomly distributed in a derivation (2/3) and in a test set (1/3). The primary end point was biopsy-proven AMR. A mixed effect logistic regression model with a random intercept was applied to identify variables independently associated with AMR. Simulation analyzes were performed. Results: The US and French cohorts comprised a total of 1341 patients, representing 12 864 EMB. Overall, 490 AMR episodes were diagnosed (3.8% of EMB). Among the 26 potential determinants of AMR, 5 variables showed independent association: time post-transplant ( P P =0.001), circulating donor-specific anti–human leukocyte antigen antibody ( P =0.001), graft dysfunction ( P =0.004), and prior history of definite AMR ( P Conclusions: Our results support the use of the AMR risk model as a clinical decision tool to minimize the number of routine EMB after heart transplantation.

BACKGROUND AND AIMS Graphical Abstract In kidney transplantation, day-zero biopsies are used to assess organ quality and discriminate lesions inherited from the donor or acquired after transplantation. However, many centres worldwide do not perform those biopsies which remain invasive, costly and may delay the transplant procedure. We aimed to develop and validate a noninvasive virtual biopsy system. METHOD A total of 17 centres were included from Europe, North America and Australia from 2000 to 2019. Candidate predictors were assessed following a prespecified protocol. Outcome measures were the day-zero biopsy lesions (Banff classification) including CV, AH, IFTA scores and % of sclerotic glomeruli. Six machine learning models were developed and their performances were assessed. RESULTS A total of 12 992 day-zero biopsies were included. Eleven parameters were used to build the classifiers, including donor age, kidney function, hypertension, BMI, proteinuria, diabetes, sex, donor type, cause of death and Hep-C status. The ensemble models (random forests, neural networks, gradient boosting, extreme gradient boosting tree, linear discriminant analysis, and naive Bayes) showed multi-AUC of 0.738, 0.817 and 0.788 for prediction of CV, AH and IFTA scores, and a good performance for predicting glomerulosclerosis (mean absolute error, MAE = 4.766). We confirmed the robustness and generalizability in multiple clinical scenarios and subpopulations and built an online interface for clinicians: https://transplant-pred/Virtual_Biopsy. CONCLUSION We developed and validated the first virtual biopsy system that enables the prediction of day-zero biopsy, based on routinely collected parameters. This can assist clinicians in assessing allograft quality, discrimination of donor derived versus acquired lesions after transplantation and prevent overdiagnosis of calcineurin inhibitor (CNI) toxicity.

BACKGROUND AND AIMS Predicting kidney transplant patient mortality has been hampered by registry-based studies and low-level phenotyped cohorts without specific design towards mortality prediction. This represents a limitation for decision making and ultimately patient care. We aimed to build a robust patient mortality prognostication system. METHOD We enrolled 1446 patients transplanted in France between 2004 and 2014 in whom a protocol-based collection including more than 160 parameters from the recipient (past medical history, risk factors) donor and graft, biological and imaging data, was performed on the day of transplantation (TX) and during the first year of transplantation. Multivariable Cox model was used to develop an individual predictive score of mortality, further improved by a Lasso regression in order to retain the strongest predictors of mortality. RESULTS Among the 1446 kidney transplant recipients included, 309 patients died after a median post-TX follow-up time of 7.6 years (IQR 5.40–10.78). Among the 120 parameters, 19 predictors were selected using lasso regression. The strongest predictors of patient survival were (1) baseline recipient factors (age, history of cancer, diabetes mellitus, chronic obstructive pulmonary disease, cardiovascular events: myocardial infarction, stroke or arteritis, supraventricular cardiac rhythm disorder, psychiatric history and VHC status); (2) post-TX parameters (need for dialysis, cardiovascular complications and cancer in the first year of TX); and (3) seven biological variables (HbA1c, C-reactive protein, albumin, gamma-glutamyl transferase, uric acid, neutrophils and urinary protein). The mortality score showed accurate calibration and discrimination at 10 years [C-statistic = 0.81; 95% confidence interval (95% CI) 0.78–0.83]. CONCLUSION We generate the first integrative patient survival score that shows a superior prediction performance when compared to previous prognostic systems, reaching 81% prediction accuracy at 10 years. A reliable survival prediction tool will enable improved patient monitoring and therapeutic decision making to alter the course of an unfavorable patient survival outcome and may provide a surrogate endpoint in clinical trials.

BACKGROUND AND AIMS Post-transplantation patient care requires development and validation of noninvasive biomarkers to improve allograft monitoring and prevention from unnecessary biopsies. Preliminary reports have suggested the association of donor derived cell-free DNA (dd-cfDNA) with allograft rejection. However, there is no proof of its added value beyond standard of care patient management in large and deep phenotyped cohorts. METHOD A total of 1210 concomitant evaluations of allograft histology, anti-HLA DSA and functional parameters between 2013 and 2018 were included corresponding to 637 evaluations in the derivation cohort and 573 in the validation cohort. dd-cfDNA was measured in plasma at the time of the evaluation. Diagnoses were assessed using Banff 2019 criteria. Parameters associated with kidney allograft rejection were assessed using uni- and multivariable logistic regression. We developed a risk model using the variables that were independently associated with rejection. RESULTS Higher levels of dd-cfDNA were observed for AMR and TCMR or both compared to other diagnoses (Figure 1A). We found incremental dd-cfDNA levels with increasing Banff lesion scores for g, ptc, i, t, cg and C4d (Figure 1B). There was no association of dd-cfDNA levels with allograft inactive lesions. In multivariable analysis, dd-cfDNA (P CONCLUSION We demonstrate the independent and added value of dd-cfDNA in addition to conventional features to predict rejection. This first integrative system shows improved performance for patient monitoring and could help physicians in decision-making process.

Peptides and peptidomimetics represent the middle space between small molecules and large proteins - they retain the relatively small size and synthetic accessibility of small molecules while providing high binding specificity for biomolecular partners typically observed with proteins. During the course of our efforts to target intracellular protein-protein interactions in cancer, we observed that the cellular uptake of peptides is critically determined by the cell line - specifically, we noted that peptides show better uptake in cancer cells with enhanced macropinocytic indices. Here, we describe the results of our analysis of cellular penetration by different classes of conformationally stabilized peptides. We tested the uptake of linear peptides, peptide macrocycles, stabilized helices, β-hairpin peptides, and crosslinked helix dimers in eleven different cell lines. Efficient uptake of these conformationally defined constructs directly correlated with the macropinocytic activity of each cell line: high uptake of compounds was observed in cells with mutations in certain signaling pathways. Significantly, the study shows that constrained peptides follow the same uptake mechanism as proteins in macropinocytic cells but, unlike proteins, peptide mimics can be readily designed to resist denaturation and proteolytic degradation. Our findings expand the current understanding of cellular uptake in cancer cells by designed peptidomimetics and suggest that cancer cells with certain mutations are suitable mediums for the study of biological pathways with peptide leads.

Background: Cardiac allograft vasculopathy (CAV) is a major contributor of heart transplant recipient mortality. Little is known about the prototypes of CAV trajectories at the population level. We aimed to identify the different evolutionary profiles of CAV and to determine the respective contribution of immune and nonimmune factors in CAV development. Methods: Heart transplant recipients were from 4 academic centers (Pitié-Salpêtrière and Georges Pompidou Hospital, Paris, Katholieke Universiteit Leuven, and Cedars-Sinai, Los Angeles; 2004–2016). Patients underwent prospective, protocol-based monitoring consisting of repeated coronary angiographies together with systematic assessments of clinical, histological, and immunologic parameters. The main outcome was a prediction for CAV trajectory. We identified CAV trajectories by using unsupervised latent class mixed models. We then identified the independent predictive variables of the CAV trajectories and their association with mortality. Results: A total of 1301 patients were included (815 and 486 in the European and US cohorts, respectively). The median follow-up after transplantation was 6.6 (interquartile range, 4–9.1) years with 4710 coronary angiographies analyzed. We identified 4 distinct profiles of CAV trajectories over 10 years. The 4 trajectories were characterized by (1) patients without CAV at 1 year and nonprogression over time (56.3%), (2) patients without CAV at 1 year and late-onset slow CAV progression (7.6%), (3) patients with mild CAV at 1 year and mild progression over time (23.1%), and (4) patients with mild CAV at 1 year and accelerated progression (13.0%). This model showed good discrimination (0.92). Among candidate predictors assessed, 6 early independent predictors of these trajectories were identified: donor age ( P P P =0.001), recipient dyslipidemia ( P =0.009), class II anti–human leukocyte antigen donor-specific antibodies ( P =0.004), and acute cellular rejection ≥2R ( P =0.028). The 4 CAV trajectories manifested consistently in the US independent cohort with similar discrimination (0.97) and in different clinical scenarios, and showed gradients for overall-cause mortality ( P Conclusions: In a large multicenter and highly phenotyped prospective cohort of heart transplant recipients, we identified 4 CAV trajectories and their respective independent predictive variables. Our results provide the basis for a trajectory-based assessment of patients undergoing heart transplantation for early risk stratification, patient monitoring, and clinical trials. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04117152.

Background: National data demonstrate a trend toward outpatient same-day mastectomy. The possible drivers of this change include the costs related to hospital admission and effective management of postoperative pain. We retrospectively analyzed our single-institution experience with outpatient same-day mastectomy that incorporates a multimodal pain management regimen. Methods: We retrospectively reviewed the medical records of patients who underwent same-day mastectomy at a single academic hospital. All patients received a multimodal, perioperative pain management regimen consisting of the intraoperative administration of 1,000 mg of intravenous (IV) acetaminophen and 30 mg of IV ketorolac, combined with the operating surgeon performing a 4- to 5-level, midaxillary, intercostal nerve block using liposomal bupivacaine. All patients were discharged with a prescription for acetaminophen with codeine, along with options for nonnarcotic alternatives as needed for pain. Results: We reviewed the data on 72 patients who underwent mastectomies: 11 (15.3%) bilateral and 61 (84.7%) unilateral. The average age was 57 years, and average body mass index was 30 kg/m2. The average length of stay of 4 to 6 hours was a marked reduction compared to a 23-hour observational period or an inpatient hospital stay. The average follow-up was 20.1 weeks. Five patients presented to the emergency department (ED) within the 30-day postoperative period, with 2 patients (2.8%) requiring readmission to the hospital for non–pain-related issues. The other 3 patients (4.2%) were evaluated for specific pain-related issues but did not require admission and were discharged home from the ED. Conclusion: Our data support outpatient same-day mastectomy incorporating a multimodal, perioperative pain management regimen as a safe and feasible treatment option. Potential additional benefits may include decreased oral opioid use and cost savings for the hospital.

BackgroundDifferent comprehensive care programmes (CCPs) have been developed for patients with chronic obstructive pulmonary disorder (COPD), but data regarding their effectiveness have been controversial. PubMed and Embase were searched to 1st June 2017 for articles that investigated the effects of the different types of CCPs on hospitalization or mortality rates in COPD.ResultsA total of 67 studies including 3472633 patients (mean age: 76.1±12.7 years old; 41% male) were analyzed. CCPs reduced all-cause hospitalizations (hazard ratio [HR]: 0.70, 95% confidence interval [CI]: 0.63-0.79; P2:96%) and mortality (HR: 0.69, 95% CI: 0.573-0.83; PI2:75%). Subgroup analyses for different CCP types were performed. Hospitalizations were reduced by pharmacist-led medication reviews (HR: 0.54; 95% CI: 0.37-0.78; P=0.001; I2:49%), structured care programmes (HR: 0.76; 95% CI: 0.66-0.87; PI2:88%) and self-management programmes (HR: 0.79; 95% CI: 0.64-0.99; PI2:78%), but not continuity of care programmes (HR: 0.70; 95% CI: 0.36-1.36; P=0.29; I2:100%), early support discharge or home care packages (HR: 0.97; 95% CI: 0.91-1.04; P=0.37; I2:0%) or telemonitoring (HR: 0.61; 95% CI: 0.32-1.18; P=0.14; I2:94%). Mortality was reduced by early support discharge or home care packages (HR: 0.49; 95% CI: 0.30-0.80; PI2:72%), structured care programmes (HR: 0.69; 95% CI: 0.53-0.90; PI2:61%) and telemonitoring (HR: 0.52; 95% CI: 0.31-0.89; PI2:0%), but not self-management programmes (HR: 0.79; 95% CI: 0.64-0.99; PI2:78%).ConclusionsComprehensive care programmes reduce hospitalization and mortality in COPD patients.

Introduction Our group has previously reported our experience in treating hand burns with 2:1 meshed autografting and simultaneous application of autologous skin cell suspension (ASCS) even when donor sites are abundant. Here, we sought to expand on this experience. We hypothesized that the use of 2:1 meshed autografting and ASCS (MA/ASCS) would provide comparable outcomes to hand burns treated with sheet graft. Methods A retrospective review was conducted of all subjects operated on for deep 2nd and 3rd degree hand burns at our ABA-verified burn center from April, 2018 to May, 2021. Exclusion criterion was a burn of >20% TBSA. The cohorts were those subjects treated with MA/ASCS versus those treated with split thickness sheet, pie-crust, or 1:1 meshed autograft alone (STAG). Outcomes included proportion returning to work (RTW), length of time for RTW, and time to wound closure. Mann-Whitney U test was used for comparisons of continuous variables, and Fishers Exact test for categorical variables. Values are reported as median and interquartile range. Results Sixty-eight subjects fit the study criteria (MA/ASCS n=43, STAG n=25). The MA/ASCS group was significantly older than the STAG cohort (45.5 yrs [32, 59.25] vs 35 [28, 45], p=0.013) with larger %TBSA burns overall (11.5% [7, 16.25] vs 2% [1, 3], p < 0.0001), and larger hand burns (186 cm2 [124.75, 330.5] vs 104 cm2 [56, 164], p=0.001). Comparable results were seen between MA/ASCS and STAG, respectively, for time to wound closure (8 days [7, 13] vs 8 [6, 14], p=0.48), proportion RTW (51% vs 64%, p=0.33), and days for RTW among those returning (38 [29.25, 62.75] vs 34.5 [20.75, 57], p=0.471). Fractional ablations were performed in 14% of the MA/ASCS group and 12% of the STAG group. Conclusions Despite being significantly older, having larger hand wounds, and larger overall wounds within the parameters of the study criteria, patients with 20% TBSA burns or smaller whose hand burns were treated with 2:1 mesh and ASCS overspray had comparable time to wound closure and return to work as subjects treated with 1:1, pie-crust, or sheet STAG.

Background Transplant glomerulopathy, a common glomerular lesion observed after kidney transplant that is associated with poor prognosis, is not a specific entity but rather the end stage of overlapping disease pathways. Its heterogeneity has not been precisely characterized to date. Methods Our study included consecutive kidney transplant recipients from three centers in France and one in Canada who presented with a diagnosis of transplant glomerulopathy (Banff cg score ≥1 by light microscopy), on the basis of biopsies performed from January of 2004 through December of 2014. We used an unsupervised archetype analysis of comprehensive pathology findings and clinical, immunologic, and outcome data to identify distinct groups of patients. Results Among the 8207 post-transplant allograft biopsies performed during the inclusion period, we identified 552 biopsy samples (from 385 patients) with transplant glomerulopathy (incidence of 6.7%). The median time from transplant to transplant glomerulopathy diagnosis was 33.18 months. Kidney allograft survival rates at 3, 5, 7, and 10 years after diagnosis were 69.4%, 57.1%, 43.3%, and 25.5%, respectively. An unsupervised learning method integrating clinical, functional, immunologic, and histologic parameters revealed five transplant glomerulopathy archetypes characterized by distinct functional, immunologic, and histologic features and associated causes and distinct allograft survival profiles. These archetypes showed significant differences in allograft outcomes, with allograft survival rates 5 years after diagnosis ranging from 88% to 22%. Based on those results, we built an online application, which can be used in clinical practice on the basis of real patients. Conclusions A probabilistic data-driven archetype analysis approach applied in a large, well defined multicenter cohort refines the diagnostic and prognostic features associated with cases of transplant glomerulopathy. Reducing heterogeneity among such cases can improve disease characterization, enable patient-specific risk stratification, and open new avenues for archetype-based treatment strategies and clinical trials optimization.

Advances in cancer research have led to the development of new therapeutics with significant and durable responses such as immune checkpoint inhibitors. More recent therapies aim to stimulate anti-tumor immune responses by targeting the tumor necrosis factor (TNF) receptors, however this approach has been shown to require clustering of receptors in order to achieve a significant response. Here we present a perspective on using transthyretin, a naturally occurring serum protein, as a drug delivery platform to enable cross-linking independent clustering of targets. TTR forms a stable homo-tetramer with exposed termini that make TTR a highly versatile platform for generating multimeric antibody fusions to enable enhanced target clustering. Fusions with antibodies or Fabs targeting TRAILR2 were shown to have robust cytotoxic activity in vitro and in vivo in colorectal xenograft models demonstrating that TTR is a highly versatile, stable, therapeutic fusion platform that can be used with antibodies, Fabs and other bioactive fusion partners and has broad applications in oncology and infectious disease research.

Aberrant Ras signaling is linked to a wide spectrum of hyperproliferative diseases, and components of the signaling pathway, including Ras, have been the subject of intense and ongoing drug discovery efforts. The cellular activity of Ras is modulated by its association with the guanine nucleotide exchange factor Son of sevenless (Sos), and the high-resolution crystal structure of the Ras-Sos complex provides a basis for the rational design of orthosteric Ras ligands. We constructed a synthetic Sos protein mimic that engages the wild-type and oncogenic forms of nucleotide-bound Ras and modulates downstream kinase signaling. The Sos mimic was designed to capture the conformation of the Sos helix-loop-helix motif that makes critical contacts with Ras in its switch region. Chemoproteomic studies illustrate that the proteomimetic engages Ras and other cellular GTPases. The synthetic proteomimetic resists proteolytic degradation and enters cells through macropinocytosis. As such, it is selectively toxic to cancer cells with up-regulated macropinocytosis, including those that feature oncogenic Ras mutations.

Triggering receptor expressed on myeloid cells 2 (TREM2) sustains microglia response to brain injury stimuli including apoptotic cells, myelin damage, and amyloid β (Aβ). Alzheimer’s disease (AD) risk is associated with the TREM2(R47H) variant, which impairs ligand binding and consequently microglia responses to Aβ pathology. Here, we show that TREM2 engagement by the mAb hT2AB as surrogate ligand activates microglia in 5XFAD transgenic mice that accumulate Aβ and express either the common TREM2 variant (TREM2(CV)) or TREM2(R47H). scRNA-seq of microglia from TREM2(CV)-5XFAD mice treated once with control hIgG1 exposed four distinct trajectories of microglia activation leading to disease-associated (DAM), interferon-responsive (IFN-R), cycling (Cyc-M), and MHC-II expressing (MHC-II) microglia types. All of these were underrepresented in TREM2(R47H)-5XFAD mice, suggesting that TREM2 ligand engagement is required for microglia activation trajectories. Moreover, Cyc-M and IFN-R microglia were more abundant in female than male TREM2(CV)-5XFAD mice, likely due to greater Aβ load in female 5XFAD mice. A single systemic injection of hT2AB replenished Cyc-M, IFN-R, and MHC-II pools in TREM2(R47H)-5XFAD mice. In TREM2(CV)-5XFAD mice, however, hT2AB brought the representation of male Cyc-M and IFN-R microglia closer to that of females, in which these trajectories had already reached maximum capacity. Moreover, hT2AB induced shifts in gene expression patterns in all microglial pools without affecting representation. Repeated treatment with a murinized hT2AB version over 10 d increased chemokines brain content in TREM2(R47H)-5XFAD mice, consistent with microglia expansion. Thus, the impact of hT2AB on microglia is shaped by the extent of TREM2 endogenous ligand engagement and basal microglia activation.

International audience; Although the gold standard of monitoring kidney transplant function relies on glomerular filtration rate (GFR), little is known about GFR trajectories after transplantation, their determinants, and their association with outcomes. To evaluate these parameters we examined kidney transplant recipients receiving care at 15 academic centers. Patients underwent prospective monitoring of estimated GFR (eGFR) measurements, with assessment of clinical, functional, histological and immunological parameters. Additional validation took place in seven randomized controlled trials that included a total of 14,132 patients with 403,497 eGFR measurements. After a median follow-up of 6.5 years, 1,688 patients developed end-stage kidney disease. Using unsupervised latent class mixed models, we identified eight distinct eGFR trajectories. Multinomial regression models identified seven significant determinants of eGFR trajectories including donor age, eGFR, proteinuria, and several significant histological features: graft scarring, graft interstitial inflammation and tubulitis, microcirculation inflammation, and circulating anti-HLA donor specific antibodies. The eGFR trajectories were associated with progression to end stage kidney disease. These trajectories, their determinants and respective associations with end stage kidney disease were similar across cohorts, as well as in diverse clinical scenarios, therapeutic eras and in the seven randomized control trials. Thus, our results provide the basis for a trajectory-based assessment of kidney transplant patients for risk stratification and monitoring.

Protein–protein interactions (PPIs) are often misregulated in disease and are attractive targets for drug discovery. Several strategies that rely on high throughput screening and rational design for developing inhibitors of protein complex formation have been described. We have pursued a rational design approach that captures the conformation of the critical binding epitope from one interacting protein partner. This approach builds on the hypothesis that binding epitopes are often defined by a handful of residues that dominate the binding energy landscape, and that mimicry of these residues would result in small- to medium-sized inhibitors of the chosen target. Here, we review our approach to develop helical mimics that capture the backbone conformation and interacting residues of the most frequently occurring secondary structure motif at protein interfaces. We describe a hydrogen bond surrogate (HBS) approach to constrain peptides into the α-helical geometry. HBS α-helices have been extensively characterized in vitro and in vivo and shown to successfully reproduce helical protein epitopes. The HBS approach has yielded effective inhibitors for multiple PPI complexes. We will continue to evolve to address the existing challenges of peptide-based therapeutics.

Protein-protein interactions (PPIs) play a critical role in fundamental biological processes. Competitive inhibition of these interfaces requires compounds that can access discontinuous binding epitopes along a large, shallow binding surface area. Conformationally-defined protein surface mimics present a viable route to target these interactions. However, the development of minimal protein mimics that engage intracellular targets with high affinity remains a major challenge because mimicry of a portion of the binding interface is often associated with the loss of critical binding interactions. Covalent targeting provides an attractive approach to overcome the loss of non-covalent contacts but have the inherent risk of dominating non-covalent contacts and increasing the likelihood of non-selective binding. Here, we report the iterative design of a proteolytically-stable α(3)β chimeric helix mimic that covalently targets oncogenic G12C Ras as a model system. We explored several electrophiles to optimize preferential alkylation with the desired C12 on Ras. The designed lead peptide modulates nucleotide exchange, inhibits activation of the Ras-mediated signaling cascade, and is selectively toxic towards mutant G12C Ras cancer cells. The relatively high frequency of acquired cysteines as missense mutations in cancer and other diseases suggests that covalent peptides may offer an untapped therapeutic approach for targeting aberrant protein interactions.

Context Pharmacological thromboprophylaxis involves a trade-off between a reduction in venous thromboembolism (VTE) and increased bleeding. No guidance specific for procedure and patient factors exists in urology. Objective To inform estimates of absolute risk of symptomatic VTE and bleeding requiring reoperation in urological non-cancer surgery. Evidence acquisition We searched for contemporary observational studies and estimated the risk of symptomatic VTE or bleeding requiring reoperation in the 4 wk after urological surgery. We used the GRADE approach to assess the quality of the evidence. Evidence synthesis The 37 eligible studies reported on 11 urological non-cancer procedures. The duration of prophylaxis varied widely both within and between procedures; for example, the median was 12.3 d (interquartile range [IQR] 3.1–55) for open recipient nephrectomy (kidney transplantation) studies and 1 d (IQR 0–1.3) for percutaneous nephrolithotomy, open prolapse surgery, and reconstructive pelvic surgery studies. Studies of open recipient nephrectomy reported the highest risks of VTE and bleeding (1.8–7.4% depending on patient characteristics and 2.4% for bleeding). The risk of VTE was low for 8/11 procedures (0.2–0.7% for patients with low/medium risk; 0.8–1.4% for high risk) and the risk of bleeding was low for 6/7 procedures (≤0.5%; no bleeding estimates for 4 procedures). The quality of the evidence supporting these estimates was low or very low. Conclusions Although inferences are limited owing to low-quality evidence, our results suggest that extended prophylaxis is warranted for some procedures (eg, kidney transplantation procedures in high-risk patients) but not others (transurethral resection of the prostate and reconstructive female pelvic surgery in low-risk patients). Patient summary The best evidence suggests that the benefits of blood-thinning drugs to prevent clots after surgery outweigh the risks of bleeding in some procedures (such as kidney transplantation procedures in patients at high risk of clots) but not others (such as prostate surgery in patients at low risk of clots).

Introduction En transplantation renale, les biopsies pre-implantatoires sont utilisees pour evaluer la qualite de l’organe et determiner les lesions histologiques heritees du donneur de celles acquissent apres la transplantation. Neanmoins, de nombreux centres ne realisent pas ces biopsies qui reste un acte invasif, couteux et chronophage. Description Cette etude vise a developper et valider un outil non invasif de biopsie virtuelle en transplantation renale base sur les caracteristiques du donneur au moment du prelevement. Methodes Les donneurs vivants et decedes preleves avec une biopsie preimplantatoire entre 2000 et 2019 de 17 centres de transplantation renale d’Europe, d’Amerique du Nord et d’Australie ont ete inclus. Les caracteristiques demographiques, cliniques et biologiques du donneur ont ete utilisees pour predire 4 lesions chroniques de la biopsie preimplantatoire : le pourcentage de glomerules scleroses et les scores de BANFF arteriosclerose (cv), hyalinose arteriolaire (ah) et fibrose interstitielle et atrophie tubulaire (FIAT). Resultats Au total, 12 992 biopsies preimplantatoire ont ete incluses et 11 parametres du donneur ont ete utilises : âge, sexe, IMC, creatinine, proteinurie, comorbidites (hypertension, diabetes, hepatite C), type de donneur et cause du deces si donneur decedes. Un metaclassifier regroupant les modeles de random forest, neural network, gradient boosting machine, extreme gradient boosting tree, linear discriminant analysis et naive Bayes a permis de predire avec une AUC de 0,736 le score cv, 0,810 le score ah et 0,793 la FIAT. Le random forest a ete utilise pour predire le pourcentage de glomerules sclereux avec une erreur absolu moyenne de 4,766. L’outil est disponible en ligne ( Fig. 1 ) : https://transplant-prediction-system.shinyapps.io/Virtual_Biopsy_System . Conclusion Cette etude presente le premier outil de biopsie virtuelle non invasive en transplantation renale montrant de bonnes performances pour predire le resultat de la biopsie preimplantatoire a partir de caracteristiques du donneur. Cet outil pourrait aider a mieux contextualiser les lesions chroniques presentes sur les biopsies apres la transplantation.

This article revisits the question of whether capital account liberalization improves access to credit by advancing and testing a theory of how the structure of the financial sector shapes the willingness and ability of banks and governments to repress the domestic financial sector. In a highly concentrated financial sector, banks and governments are more willing to reap the benefits of financial openness by suppressing liberalizing reforms to domestic financial policies, and they can also better coordinate with one another to stifle these reforms compared to when the financial sector is diffuse. Using a panel dataset of Latin American and Caribbean countries, I find that capital account liberalization leads to a decrease in loans to private firms and households and an increase in loans to governments and state-owned enterprises when the financial sector is highly concentrated. Only when the financial sector is diffuse does capital account liberalization lead to reforms in entry barriers, directed...

Affinity purification, such as Protein A (ProA) followed by size exclusion chromatography (SEC) remains a popular method to obtain research scale proteins. With the need for higher throughput protein production increasing for discovery research, there is substantial interest in the automation of complex protein purification processes, which often start with a ProA step followed by SEC. However, the harsh elution conditions from ProA based chromatography can destabilize some proteins resulting in particulates, which in turn can cause column fouling and potential cross-contamination of subsequent purifications. We modified both Bio Rad NGC and AKTA Pure systems to run a three-column process (ProA to buffer exchange to SEC) enabling automated tandem affinity to SEC purification while minimizing the risk of SEC column fouling and subsequent cross-contamination. The intervening buffer exchange column, unlike the final SEC column, can be rapidly regenerated using harsh methods between runs, and these automated systems are capable of processing up to six samples per day without user intervention.

Acquired tracheoesophageal fistulas are rare but associated with significant morbidity and mortality. The majority of cases are due to prolonged or complicated endotracheal intubation, tracheostomy, or esophageal malignancy, or subsequent to radiation or chemotherapy for treatment of the latter. Other etiologies include esophageal stenting and complications secondary to endoscopic procedures. The pathophysiology involves chronic inflammation of the esophagus or posterior wall of the trachea, ultimately promoting fistulization between these two structures. Risk factors primarily depend on the etiology; however, excessive balloon pressures and prolonged intubation are among the strongest predictors of acquired tracheoesophageal fistula. In two reported cases, intubation with persistent air leaks resulted in fistulization. Patients present with refractory pneumonia, aspiration, hypoxemia, acute respiratory distress, enteral feed in endotracheal aspirate, or gastric distention following extubation. It can be difficult to distinguish normal functional deterioration from deterioration secondary to intubation. Up to 51% of patients intubated for at least 48 hours may experience dysphagia following extubation. Ultimately, the diagnostic algorithm includes an esophagogram, followed by imaging with computed tomography (CT) scan, and, more recently, CT scan with three-dimensional reconstructions, a bronchoscopy, and an esophagoscopy. Spontaneous closure rarely occurs, and the primary treatment modalities include interventional therapy with stenting via bronchoscopy, esophagoscopy, or surgical correction. Surgical intervention is associated with higher risks due to surrounding vital anatomy and, often, technical challenges requiring multispecialty care. Our case study presents a novel and effective method of repairing a benign acquired tracheoesophageal fistula utilizing the transverse cervical artery flap.

Background: Owing to the limited data on long-term outcomes following the implantation of atrial septal occluders, their permanent nature and potential for adverse outcomes remain concerning. Methods: In this retrospective cohort study, the long-term outcomes of adult patients who underwent transcatheter and surgical closure at Peter Munk Cardiac Centre, Toronto, Canada between 1991-2015 were determined using administrative databases linkages. The transcatheter group was compared to an age-sex matched population (each included 1278 participants) in 1:1 fashion and to a surgical group (240 patients) using propensity weighting. The primary endpoint was all-cause mortality. Results: Median age was 48 years and 39 years for the transcatheter and surgical groups respectively. Compared to age-sex matched group, mortality following transcatheter closure was not significantly different after a median follow-up of 9 years [7.9 vs 6.4 per 1000-patient-years, (difference-95%CI, -0.68,4.49), P=0.20], with non-significantly different rates of stroke [1.9 vs 1.1 per 1000-patient-years, (difference-95% CI, -0.2,2.69), P=0.16] but significantly higher rates of atrial fibrillation [22 vs 4.4 per 1000-patient-years, (difference-95% CI, 11.6,25.9), P

Objectives This study reviewed a series of patients treated with transcatheter closure of septal defect to treat platypnea-orthodeoxia syndrome, with specific attention to septal characteristics and device choice. Background Platypnea–orthodeoxia syndrome is an uncommon condition characterized by positional dyspnea and hypoxemia due to intracardiac right-to-left shunting through a patent foramen ovale (PFO), an atrial septal defect, or pulmonary arteriovenous malformations. Percutaneous closure of such defects is the treatment of choice. Methods In this single-center series, 52 patients were treated with percutaneous closure of an interatrial communication after presentation between January 1997 and July 2015. Septal morphology, clinical, procedural, and outcomes data were analyzed. Results All patients had a PFO; however, nearly one-quarter required a non-PFO device (11 Amplatzer Septal Occluder and 1 post-infarct muscular VSD), as opposed to a dedicated PFO device to achieve shunt occlusion. These patients were characterized by an aneurysmal septum, shorter primum septum overlap with the secundum septum, and greater septal angulation from the midline. After closure, all demonstrated acute improvements in oxygen saturation (pre-procedure: 81 ± 8%; post-procedure: 95.1 ± 0.5% on room air). Each patient was treated with a single device and no one required re-intervention. Conclusions Patients presenting with platypnea–orthodeoxia syndrome can be treated successfully with a percutaneous intervention often requiring a variety of devices. Those requiring a non-PFO–type device had a greater prevalence of an aneurysmal septum, shorter primum septal overlap with the secundum septum, and greater septal angulation with the midline.

Does capital account liberalization improve access to finance? A rich body of evidence suggests that it does, but there are many empirical discrepancies to this relationship, especially in Latin America. When the financial sector is highly concentrated, the incentives of banks and governments are aligned to enlarge the opportunities to gain from financial openness by suppressing policies that reform the domestic financial sector. The result is that capital account liberalization that occurs in such a context should improve access to credit for governments but impede access to credit among private firms and households.

Pulmonary hypertension is a rare disorder that, without treatment, is progressive and fatal within 3–4 years. Current treatment involves a diverse group of drugs that target the pulmonary vascular bed. In addition, strategies that increase nitric oxide (NO) formation have a beneficial effect in rodents and patients. Nebivolol, a selective β1 adrenergic receptor-blocking agent reported to increase NO production and stimulate β3 receptors, has vasodilator properties suggesting that it may be beneficial in the treatment of pulmonary hypertension. The present study was undertaken to determine whether nebivolol has a beneficial effect in monocrotaline-induced (60 mg/kg) pulmonary hypertension in the rat. These results show that nebivolol treatment (10 mg/kg, once or twice daily) attenuates pulmonary hypertension, reduces right ventricular hypertrophy, and improves pulmonary artery remodeling in monocrotaline-induced pulmonary hypertension. This study demonstrates the presence of β3 adrenergic receptor immunoreactivity in pulmonary arteries and airways and that nebivolol has pulmonary vasodilator activity. Studies with β3 receptor agonists (mirabegron, BRL 37344) and antagonists suggest that β3 receptor-mediated decreases in systemic arterial pressure occur independent of NO release. Our results suggest that nebivolol, a selective vasodilating β1 receptor antagonist that stimulates β3 adrenergic receptors and induces vasodilation by increasing NO production, may be beneficial in treating pulmonary hypertensive disorders.

Background Apheresis-based desensitization allows for successful transplantation across major immunological barriers. For donor-specific antibody (DSA)- and/or crossmatch-positive transplantation, however, it has been shown that even intense immunomodulation may not completely prevent antibody-mediated rejection (ABMR). Methods In this study, we evaluated transplant outcomes in 101 DSA+ deceased donor kidney transplant recipients (transplantation between 2009 and 2013; median follow-up: 24 months) who were subjected to immunoadsorption (IA)-based desensitization. Treatment included a single pre-transplant IA session, followed by anti-lymphocyte antibody and serial post-transplant IA. In 27 cases, a positive complement-dependent cytotoxicity crossmatch (CDCXM) was rendered negative immediately before transplantation. Seventy-four of the DSA+ recipients had a negative CDCXM already before IA. Results Three-year death-censored graft survival in DSA+ patients was significantly worse than in 513 DSA- recipients transplanted during the same period (79 versus 88%, P = 0.008). Thirty-three DSA+ recipients (33%) had ABMR. While a positive baseline CDCXM showed only a trend towards higher ABMR rates (41 versus 30% in CDCXM- recipients, P = 0.2), DSA mean fluorescence intensity (MFI) in single bead assays significantly associated with rejection, showing 20 versus 71% ABMR rates at 15 000 peak DSA MFI. The predictive value of MFI was moderate, with the highest accuracy at a median of 13 300 MFI (after cross-validation: 0.72). Other baseline variables, including CDC assay results, human leukocyte antigen mismatch, prior transplantation or type of induction treatment, did not add independent predictive information. Conclusions IA-based desensitization failed to prevent ABMR in a considerable number of DSA+ recipients. Assessing DSA MFI may help stratify risk of rejection, supporting its use as a guide to organ allocation and individualized treatment.

This pilot study explores sleep disruption after total knee arthroplasty and the impact of melatonin on sleep and postoperative pain. Sleep time was decreased on the last preoperative night and first two postoperative nights. Sleep efficiency was decreased on all three postoperative nights. Compared to placebo, melatonin increased sleep efficiency by 4.4% (mean; 95% CI -1.6, 10.4; P=0.150) and sleep time by 29 min (mean; 95% CI -2.0, 60.4; P=0.067). Melatonin appeared to have no effect on subjective sleep quality or daytime sleepiness, pain at rest or pain with standardized activity. In conclusion, sleep quality is impaired after total knee arthroplasty and exogenous melatonin does not appear to improve postoperative sleep or pain to a significant degree.

Background There is a paucity of data about the mechanisms by which sacubitril/valsartan (also known as LCZ696) improves outcomes in patients with heart failure. Specifically, the effects of sacubitril/valsartan on vascular function and NO bioavailability have not been investigated. We hypothesized that sacubitril/valsartan therapy increases circulating NO levels and improves vascular function in the setting of heart failure. Methods and Results Male spontaneously hypertensive rats underwent myocardial ischemia/reperfusion surgery to induce heart failure and were followed for up to 12 weeks with serial echocardiography. Rats received sacubitril/valsartan (68 mg/kg), valsartan (31 mg/kg), or vehicle starting at 4 weeks after reperfusion. At 8 or 12 weeks of reperfusion, animals were euthanized and tissues were collected for ex vivo analyses of NO bioavailability, aortic vascular reactivity, myocardial and vascular histology, and cardiac molecular assays. Left ventricular structure and function were improved by both valsartan and sacubitril/valsartan compared with vehicle. Sacubitril/valsartan resulted in superior cardiovascular benefits, as evidenced by sustained improvements in left ventricular ejection fraction and end‐diastolic pressure. Ex vivo vascular function, as measured by aortic vasorelaxation responses to acetylcholine and sodium nitroprusside, was significantly improved by valsartan and sacubitril/valsartan, with more sustained improvements afforded by sacubitril/valsartan. Furthermore, myocardial NO bioavailability was significantly enhanced in animals receiving sacubitril/valsartan therapy. Conclusions Sacubitril/valsartan offers superior cardiovascular protection in heart failure and improves vascular function to a greater extent than valsartan alone. Sacubitril/valsartan‐mediated improvements in cardiac and vascular function are likely related to increases in NO bioavailability and explain, in part, the benefits beyond angiotensin receptor blockade.

Context Pharmacological thromboprophylaxis involves balancing a lower risk of venous thromboembolism (VTE) against a higher risk of bleeding, a trade-off that critically depends on the risks of VTE and bleeding in the absence of prophylaxis (baseline risk). Objective To provide estimates of the baseline risk of symptomatic VTE and bleeding requiring reoperation in urological cancer surgery. Evidence acquisition We identified contemporary observational studies reporting symptomatic VTE or bleeding after urological procedures. We used studies with the lowest risk of bias and accounted for use of thromboprophylaxis and length of follow-up to derive best estimates of the baseline risks within 4 wk of surgery. We used the GRADE approach to assess the quality of the evidence. Evidence synthesis We included 71 studies reporting on 14 urological cancer procedures. The quality of the evidence was generally moderate for prostatectomy and cystectomy, and low or very low for other procedures. The duration of thromboprophylaxis was highly variable. The risk of VTE in cystectomies was high (2.6–11.6% across risk groups) whereas the risk of bleeding was low (0.3%). The risk of VTE in prostatectomies varied by procedure, from 0.2–0.9% in robotic prostatectomy without pelvic lymph node dissection (PLND) to 3.9–15.7% in open prostatectomy with extended PLND. The risk of bleeding was 0.1–1.0%. The risk of VTE following renal procedures was 0.7–2.9% for low-risk patients and 2.6–11.6% for high-risk patients; the risk of bleeding was 0.1–2.0%. Conclusions Extended thromboprophylaxis is warranted in some procedures (eg, open and robotic cystectomy) but not others (eg, robotic prostatectomy without PLND in low-risk patients). For “close call” procedures, decisions will depend on values and preferences with regard to VTE and bleeding. Patient summary Clinicians often give blood thinners to patients to prevent blood clots after surgery for urological cancer. Unfortunately, blood thinners also increase bleeding. This study provides information on the risk of clots and bleeding that is crucial in deciding for or against giving blood thinners.

Hydrogen sulfide (H2S) is a biologically active endogenous gasotransmitter formed in penile tissue that has been shown to relax isolated cavernosal smooth muscle. In the present study, erectile responses to the H2S donors sodium sulfide (Na2S) and sodium hydrosulfide (NaHS) were investigated in the anesthetized rat. Intracavernosal injections of Na2S in doses of 0.03–1 mg/kg increased intracavernosal pressure and transiently decreased mean arterial pressure in a dose-dependent manner. Blood pressure responses to Na2S were rapid in onset and short in duration. Responses to Na2S and NaHS were similar at doses up to 0.3 mg/kg, after which a plateau in the erectile response to NaHS was reached. Increases in intracavernosal pressure in response to Na2S were attenuated by tetraethylammonium (K+ channel inhibitor) and iberiotoxin (large-conductance Ca2+-activated K+ channel inhibitor), whereas glybenclamide [ATP-sensitive K+ (KATP) channel inhibitor] and inhibitors of nitric oxide (NO) synthase, cyclooxygenase, and cytochrome P-450 epoxygenase had no effect. These data indicate that erectile responses to Na2S are mediated by a tetraethylammonium- and iberiotoxin-sensitive mechanism and that KATP channels, NO, or arachidonic acid metabolites are not involved. Na2S did not alter erectile responses to sodium nitroprusside (NO donor) or cavernosal nerve stimulation, indicating that neither NO nor cGMP metabolism are altered. Thus, Na2S has erectile activity mediated by large-conductance Ca2+-activated K+ channels. It is suggested that strategies that increase H2S formation in penile tissue may be useful in the treatment of erectile dysfunction when NO bioavailability, KATP channel function, or poor responses to PGE1 are present.

Hydrogen sulfide (H2S) is an endogenous gaseous molecule formed from L-cysteine in vascular tissue. In the present study, cardiovascular responses to the H2S donors Na2S and NaHS were investigated in the anesthetized rat. The intravenous injections of Na2S and NaHS 0.03–0.5 mg/kg produced dose-related decreases in systemic arterial pressure and heart rate, and at higher doses decreases in cardiac output, pulmonary arterial pressure, and systemic vascular resistance. H2S infusion studies show that decreases in systemic arterial pressure, heart rate, cardiac output, and systemic vascular resistance are well-maintained, and responses to Na2S are reversible. Decreases in heart rate were not blocked by atropine, suggesting that the bradycardia was independent of parasympathetic activation and was mediated by an effect on the sinus node. The decreases in systemic arterial pressure were not attenuated by hexamethonium, glybenclamide, Nw-nitro-l-arginine methyl ester hydrochloride, sodium meclofenamate, ODQ, miconazole, 5-hydroxydecanoate, or tetraethylammonium, suggesting that ATP-sensitive potassium channels, nitric oxide, arachidonic acid metabolites, cyclic GMP, p450 epoxygenase metabolites, or large conductance calcium-activated potassium channels are not involved in mediating hypotensive responses to the H2S donors in the rat and that responses are not centrally mediated. The present data indicate that decreases in systemic arterial pressure in response to the H2S donors can be mediated by decreases in vascular resistance and cardiac output and that the donors have an effect on the sinus node independent of the parasympathetic system. The present data indicate that the mechanism of the peripherally mediated hypotensive response to the H2S donors is uncertain in the intact rat.

Does democracy induce financial development? There are good theoretical reasons to believe this to be the case, but the evidence adduced to support this claim has been mixed. In this article, the authors posit that only democracies that appeal to the median voter should experience financial development because those democracies have adopted their own constitution after transition, rather than having inherited one from an authoritarian predecessor. The authors empirically test this theory by focusing attention on Latin America, where there have been several reversals and improvements in financial outcomes and where many countries have cycled between regime types. They find robust support for it across different specifications. While popular democracies tend to reform their financial systems, have greater participation in the banking system, increase the supply of credit and reduce its price, and grow their stock markets, elite-biased democracies do not.

Our aim was to find out whether simplified drilling protocols would provide biological responses comparable to those of conventional drilling protocols at the low rotational speed of 400rpm. Seventy-eight root form endosseous implants with diameters of 3.75, 4.2, and 5mm were placed into canine tibias and allowed to heal for 3 and 5 weeks. After the dogs had been killed, the samples of implanted bone were retrieved and processed for non-decalcified histological sectioning. Bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) analyses were made on the histological sections. Implants treated by the simplified protocol resulted in BIC and BAFO values comparable to those obtained with the conventional drilling protocol, and there were no significant differences in the technique or diameter of the drilling. The results suggest that the simplified procedure gives biological outcomes comparable to those of the conventional procedure.

Micro- and nanoscale surface modifications have been the focus of multiple studies in the pursuit of accelerating bone apposition or osseointegration at the implant surface. Here, we evaluated histological and nanomechanical properties, and gene expression, for a microblasted surface presenting nanometer-scale texture within a micrometer-scale texture (MB) (Ossean Surface, Intra-Lock International, Boca Raton, FL) versus a dual-acid etched surface presenting texture at the micrometer-scale only (AA), in a rodent femur model for 1, 2, 4, and 8weeks in vivo. Following animal sacrifice, samples were evaluated in terms of histomorphometry, biomechanical properties through nanoindentation, and gene expression by real-time quantitative reverse transcription polymerase chain reaction analysis. Although the histomorphometric, and gene expression analysis results were not significantly different between MB and AA at 4 and 8 weeks, significant differences were seen at 1 and 2 weeks. The expression of the genes encoding collagen type I (COL-1), and osteopontin (OPN) was significantly higher for MB than for AA at 1 week, indicating up-regulated osteoprogenitor and osteoblast differentiation. At 2 weeks, significantly up-regulated expression of the genes for COL-1, runt-related transcription factor 2 (RUNX-2), osterix, and osteocalcin (OCN) indicated progressive mineralization in newly formed bone. The nanomechanical properties tested by the nanoindentation presented significantly higher-rank hardness and elastic modulus for the MB compared to AA at all time points tested. In conclusion, the nanotopographical featured surfaces presented an overall higher host-to-implant response compared to the microtextured only surfaces. The statistical differences observed in some of the osteogenic gene expression between the two groups may shed some insight into the role of surface texture and its extent in the observed bone healing mechanisms.

The present study aimed to characterize the mechanical response of beagle sartorius muscle fibers under strain rates that increase logarithmically (0.1mm/min, 1mm/min and 10mm/min), and provide an analysis of the fracture patterns of these tissues via scanning electron microscopy (SEM). Muscle tissue from dogs' sartorius was excised and test specimens were sectioned with a lancet into sections with nominal length, width, and thickness of 7, 2.5 and 0.6mm, respectively. Trimming of the tissue was done so that the loading would be parallel to the direction of the muscle fiber. Samples were immediately tested following excision and failures were observed under the SEM. No statistically significant difference was observed in strength between the 0.1mm/min (2.560±0.37MPa) and the 1mm/min (2.702±0.55MPa) groups. However, the 10mm/min group (1.545±0.50MPa) had a statistically significant lower strength than both the 1mm/min group and the 0.1mm/min group with p0.01 in both cases. At the 0.1mm/min rate the primary fracture mechanism was that of a shear mode failure of the endomysium with a significant relative motion between fibers. At 1mm/min this continues to be the predominant failure mode. At the 10mm/min strain rate there is a significant change in the fracture pattern relative to other strain rates, where little to no evidence of endomysial shear failure nor of significant motion between fibers was detected.

This in vivo study investigated the in vivo performance of two newly developed synthetic bone substitutes and compared them to commercially available xenografts (Bio-Oss, Geistlich Pharma AG, Switzerland; OsteoGraf, Dentsply, USA). The materials were tested in a rabbit calvaria model, and the bone forming properties were observed at 4 and 8 weeks after implantation by means of histomorphometry and micro computed tomography (micro-CT). Defects without any graft material were used as negative controls. Micro-CT showed that all materials tested presented new bone formation that filled the defects at both time points, whereas the negative control presented less bone formation, with soft tissue infiltration into the defects. Comparable bone fill percentages were observed for histomorphometric and micro-CT results. Even though no statistically significant difference was found quantitatively between all of the bone graft substitute groups, a higher mean decrease in graft material filling the defects, along with higher remodelling activity, was evident for the experimental materials compared to the commercially available xenografts at 8 weeks. The results indicate that the experimental materials possess high degradability, along with osteoconduction comparable to commercially available xenografts.