Machine learning analysis of contrast-enhanced ultrasound (CEUS) for the diagnosis of acute graft dysfunction in kidney transplant recipients.

AIM: The aim of the study was to develop machine learning algorithms (MLA) for diagnosing acute graft dysfunction (AGD) in kidney transplant recipients based on contrast-enhanced ultrasound (CEUS) analysis of the graft.Materials and methods: This prospective study involved 71 patients with kidney transplant undergoing CEUS during follow-up. AGD wasdefined as an increase in serum creatinine levels of at least 25% compared to the baseline of the last three months. The control group consisted of patients with stable kidney graft function (SGF). The top five CEUS parameters that achieved the best discrimination between the AGD and SGF groups were selected based on ANOVA testing and then employed as input for training MLA (naïve Bayes (NB), k-nearest neighbors (k-NN), and logistic regression (LR)). The models were validated by leave-one-out cross-validation. RESULTS: Among the 111 CEUS analyses, 21 corresponded to the AGD group and 90 to the SGF group. CEUS analyses yielded 44 parameters, from which five were selected: the wash out rate in segmental arteries,time to peak in segmental arteries, medullary mean transit time, renal mean transit time, and medullary time to fall. These five parameters were employed as input for MLA, yielding an AUROC of 0.68 for NB and k-NN and 0.72 for LR. The inclusion of graft survival in the MLA significantly improved discrimination accuracy, yielding an AUROC of 0.79 for NB, 0.76 for k-NN,and 0.81 for LR. CONCLUSIONS: The use of MLA represents a promising strategy for analyzing CEUS-derived parameters in the setting AGD.

Mechanical ventilation guided by driving pressure optimizes local pulmonary biomechanics in an ovine model.

Mechanical ventilation exposes the lung to injurious stresses and strains that can negatively affect clinical outcomes in acute respiratory distress syndrome or cause pulmonary complications after general anesthesia. Excess global lung strain, estimated as increased respiratory system driving pressure, is associated with mortality related to mechanical ventilation. The role of small-dimension biomechanical factors underlying this association and their spatial heterogeneity within the lung are currently unknown. Using four-dimensional computed tomography with a voxel resolution of 2.4 cubic millimeters and a multiresolution convolutional neural network for whole-lung image segmentation, we dynamically measured voxel-wise lung inflation and tidal parenchymal strains. Healthy or injured ovine lungs were evaluated as the mechanical ventilation positive end-expiratory pressure (PEEP) was titrated from 20 to 2 centimeters of water. The PEEP of minimal driving pressure (PEEPDP) optimized local lung biomechanics. We observed a greater rate of change in nonaerated lung mass with respect to PEEP below PEEPDP compared with PEEP values above this threshold. PEEPDP similarly characterized a breaking point in the relationships between PEEP and SD of local tidal parenchymal strain, the 95th percentile of local strains, and the magnitude of tidal overdistension. These findings advance the understanding of lung collapse, tidal overdistension, and strain heterogeneity as local triggers of ventilator-induced lung injury in large-animal lungs similar to those of humans and could inform the clinical management of mechanical ventilation to improve local lung biomechanics.

Reemergence of Oropouche virus between 2023 and 2024 in Brazil.

Background: Oropouche virus (OROV; species Orthobunyavirus oropoucheense) is an arthropod-borne virus that has caused outbreaks of Oropouche fever in Central and South America since the 1950s. This study investigates virological factors contributing to the reemergence of Oropouche fever in Brazil between 2023 and 2024. Methods: In this study, we combined OROV genomic, molecular, and serological data from Brazil from 1 January 2015 to 29 June 2024, along with in vitro and in vivo characterization. Molecular screening data included 93 patients with febrile illness between January 2023 and February 2024 from the Amazonas State. Genomic data comprised two genomic OROV sequences from patients. Serological data were obtained from neutralizing antibody tests comparing the prototype OROV strain BeAn 19991 and the 2024 epidemic strain. Epidemiological data included aggregated cases reported to the Brazilian Ministry of Health from 1 January 2014 to 29 June 2024. Findings: In 2024, autochthonous OROV infections were detected in previously non-endemic areas across all five Brazilian regions. Cases were reported in 19 of 27 federal units, with 83.2% (6,895 of 8,284) of infections in Northern Brazil and a nearly 200-fold increase in incidence compared to reported cases over the last decade. We detected OROV RNA in 10.8% (10 of 93) of patients with febrile illness between December 2023 and May 2024 in Amazonas. We demonstrate that the 2023-2024 epidemic was caused by a novel OROV reassortant that replicated approximately 100-fold higher titers in mammalian cells compared to the prototype strain. The 2023-2024 OROV reassortant displayed plaques earlier than the prototype, produced 1.7 times more plaques, and plaque sizes were 2.5 larger compared to the prototype. Furthermore, serum collected in 2016 from previously OROV-infected individuals showed at least a 32-fold reduction in neutralizing capacity against the reassortment strain compared to the prototype. Interpretation: These findings provide a comprehensive assessment of Oropouche fever in Brazil and contribute to a better understanding of the 2023-2024 OROV reemergence. The recent increased incidence may be related to a higher replication efficiency of a new reassortant virus that also evades previous immunity.

Importance of the Cysteine-Rich Domain of Snake Venom Prothrombin Activators: Insights Gained from Synthetic Neutralizing Antibodies.

Snake venoms are cocktails of biologically active molecules that have evolved to immobilize prey, but can also induce a severe pathology in humans that are bitten. While animal-derived polyclonal antivenoms are the primary treatment for snakebites, they often have limitations in efficacy and can cause severe adverse side effects. Building on recent efforts to develop improved antivenoms, notably through monoclonal antibodies, requires a comprehensive understanding of venom toxins. Among these toxins, snake venom metalloproteinases (SVMPs) play a pivotal role, particularly in viper envenomation, causing tissue damage, hemorrhage and coagulation disruption. One of the current challenges in the development of neutralizing monoclonal antibodies against SVMPs is the large size of the protein and the lack of existing knowledge of neutralizing epitopes. Here, we screened a synthetic human antibody library to isolate monoclonal antibodies against an SVMP from saw-scaled viper (genus Echis) venom. Upon characterization, several antibodies were identified that effectively blocked SVMP-mediated prothrombin activation. Cryo-electron microscopy revealed the structural basis of antibody-mediated neutralization, pinpointing the non-catalytic cysteine-rich domain of SVMPs as a crucial target. These findings emphasize the importance of understanding the molecular mechanisms of SVMPs to counter their toxic effects, thus advancing the development of more effective antivenoms.

Profiles of alcohol intoxication and their associated risks in young adults' natural settings: A multilevel latent profile analysis applied to daily transdermal alcohol concentration data.

OBJECTIVE: Transdermal alcohol concentration (TAC) sensors capture aspects of drinking events that self-reports cannot. The multidimensional nature of TAC data allows novel classification of drinking days and identification of associated behavioral and contextual risks. We used multilevel latent profile analysis (MLPA) to create day-level profiles of TAC features and test their associations with (a) daily behaviors and contexts and (b) risk for alcohol use disorders at baseline. METHOD: Two hundred twenty-two regularly heavy-drinking young adults (Mage = 22.3) completed the Alcohol Use Disorders Identification Test (AUDIT) at baseline and then responded to mobile phone surveys and wore TAC sensors for six consecutive days. MLPA identified day-level profiles using four TAC features (peak, rise rate, fall rate, and duration). TAC profiles were tested as correlates of daily drinking behaviors, contexts, and baseline AUDIT. RESULTS: Four profiles emerged: (a) high-fast (8.5% of days), (b) moderate-fast (12.8%), (c) low-slow (20.4%), and (d) little-to-no drinking days (58.2%). Profiles differed in the odds of risky drinking behaviors and contexts. The highest risk occurred on high-fast days, followed by moderate-fast, low-slow, and little-to-no drinking days. Higher baseline AUDIT predicted higher odds of high-fast and moderate-fast days. CONCLUSIONS: Days with high and fast intoxication are reflective of high-risk drinking behaviors and were most frequent among those at risk for alcohol use disorders. TAC research using MLPA may offer novel and important insights to intervention efforts. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Normothermic regional perfusion in controlled DCD liver procurement: Outcomes of the Swedish national implementation protocol.

Liver transplantation (LTX) using donors after controlled circulatory death (cDCD) is associated with poorer graft survival and increased incidence of nonanastomotic biliary strictures (NASs) compared to livers procured from brain-dead donors (DBD). The use of normothermic regional perfusion (NRP) during cDCD procurement may improve posttransplant outcomes and reduce the incidence of NAS. In Sweden, cDCD LTX was introduced through a national pilot protocol with mandatory NRP. This study aims to evaluate the outcome of cDCD LTX during the pilot period. Donor and recipient data were collected on all cDCD liver transplants during the pilot period between January 2020 to December 2022. Outcome on NAS, patient and graft survival, early allograft dysfunction, acute kidney injury, and comprehensive complication index was compared to a matched cohort of 28 patients transplanted with a DBD liver between 2018 and 2022. Eighteen patients were transplanted with a liver from a cDCD donor after using NRP. The mean functional warm ischemia time was 29 ± 6 minutes. The mean lactate reduction during NRP was 8.7 ± 2.4 mmol/L, and the end NRP perfusate alanine aminotransferase was 1.4 ± 1 µkat/L. When comparing recipients of cDCD liver transplant to DBD, no significant differences were observed in the incidence of NAS, patient and graft survival, comprehensive complication index, early allograft dysfunction, or acute kidney injury. Study protocol magnetic resonance cholangiopancreatography in cDCD patients showed no signs of subclinical biliary strictures. Evaluation of the Swedish national pilot of cDCD LTX with mandatory NRP shows comparable outcomes to a matched DBD cohort with 94.4% 1-year patient and graft survival and no incidence of NAS within the first year.

Structural and mechanistic studies on human LONP1 redefine the hand-over-hand translocation mechanism.

AAA+ enzymes use energy from ATP hydrolysis to remodel diverse cellular targets. Structures of substrate-bound AAA+ complexes suggest that these enzymes employ a conserved hand-over-hand mechanism to thread substrates through their central pore. However, the fundamental aspects of the mechanisms governing motor function and substrate processing within specific AAA+ families remain unresolved. We used cryo-electron microscopy to structurally interrogate reaction intermediates from in vitro biochemical assays to inform the underlying regulatory mechanisms of the human mitochondrial AAA+ protease, LONP1. Our results demonstrate that substrate binding allosterically regulates proteolytic activity, and that LONP1 can adopt a configuration conducive to substrate translocation even when the ATPases are bound to ADP. These results challenge the conventional understanding of the hand-over-hand translocation mechanism, giving rise to an alternative model that aligns more closely with biochemical and biophysical data on related enzymes like ClpX, ClpA, the 26S proteasome, and Lon protease.

Dysferlin Enables Tubular Membrane Proliferation in Cardiac Hypertrophy.

BACKGROUND: Cardiac hypertrophy compensates for increased biomechanical stress of the heart induced by prevalent cardiovascular pathologies but can result in heart failure if left untreated. Here, we hypothesized that the membrane fusion and repair protein dysferlin is critical for the integrity of the transverse-axial tubule (TAT) network inside cardiomyocytes and contributes to the proliferation of TAT endomembranes during pressure overload-induced cardiac hypertrophy. METHODS: Stimulated emission depletion and electron microscopy were used to localize dysferlin in mouse and human cardiomyocytes. Data-independent acquisition mass spectrometry revealed the cardiac dysferlin interactome and proteomic changes of the heart in dysferlin-knockout mice. After transverse aortic constriction, we compared the hypertrophic response of wild-type versus dysferlin-knockout hearts and studied TAT network remodeling mechanisms inside cardiomyocytes by live-cell membrane imaging. RESULTS: We localized dysferlin in a vesicular compartment in nanometric proximity to contact sites of the TAT network with the sarcoplasmic reticulum, a.k.a. junctional complexes for Ca2+-induced Ca2+ release. Interactome analyses demonstrated a novel protein interaction of dysferlin with the membrane-tethering sarcoplasmic reticulum protein juncophilin-2, a putative interactor of L-type Ca2+ channels and ryanodine receptor Ca2+ release channels in junctional complexes. Although the dysferlin-knockout caused a mild progressive phenotype of dilated cardiomyopathy, global proteome analysis revealed changes preceding systolic failure. Following transverse aortic constriction, dysferlin protein expression was significantly increased in hypertrophied wild-type myocardium, while dysferlin-knockout animals presented markedly reduced left-ventricular hypertrophy. Live-cell membrane imaging showed a profound reorganization of the TAT network in wild-type left-ventricular myocytes after transverse aortic constriction with robust proliferation of axial tubules, which critically depended on the increased expression of dysferlin within newly emerging tubule components. CONCLUSIONS: Dysferlin represents a new molecular target in cardiac disease that protects the integrity of tubule-sarcoplasmic reticulum junctional complexes for regulated excitation-contraction coupling and controls TAT network reorganization and tubular membrane proliferation in cardiomyocyte hypertrophy induced by pressure overload.

Location of medial collateral ligament tears: introduction to a magnetic resonance imaging-based classification.

PURPOSE: Despite established tear grade classifications, there is currently no radiological classification for sMCL tear locations. This study aims to establish a magnetic resonance imaging (MRI) tear location classification system for sMCL tears, to enhance understanding and guide treatment decisions by categorizing tear types. METHODS: A retrospective search in a single institution's MRI database identified patients with acute, Grade III sMCL tears (< 30 days between injury and MRI) from January to December 2022. Non-acute and partial tears were excluded, and three observers assessed tear types based on the proposed sMCL MRI tear location system: type I (proximal 25%), Ib (proximal femoral bony avulsion), II (midsubstance, 25-75%), III (distal 25%), IIIb (distal tibial bony avulsion), IIIs (Stener-like lesion). The interclass correlation coefficient (ICC) was used to assess interrater and intrarater reliability for continuous data; Fleiss and Cohen's kappa assessed interrater and intrarater reliability for categorical data. RESULTS: MRI scans of thirty patients with diagnosed sMCL injuries (53% female, mean age 37 ± 13 years, range 16-68 years) were included based on inclusion/exclusion criteria. Interrater reliability was excellent (ICC: 0.968, 95% CI, 0.933-0.985), and intrarater reliability was excellent (ICC: 0.938, 95% CI: 0.874-0.970 & 0.900, 95% CI, 0.789-0.952). Type I injuries were most common (60%), followed by type III (33.3%), type II (3.3%), type Ib (3.3%), type IIIb (0.0%), and type IIIs (0.0%). CONCLUSION: The presented MRI-based sMCL tear location classification provides a reproducible system for grading high-grade sMCL injuries. We propose that this framework will significantly unify tear location understanding and support more informed treatment decisions.

Meiofauna at a tropical sandy beach in the SW Atlantic: the influence of seasonality on diversity.

Background: Sandy beaches are dynamic environments housing a large diversity of organisms and providing important environmental services. Meiofaunal metazoan are small organisms that play a key role in the sediment. Their diversity, distribution and composition are driven by sedimentary and oceanographic parameters. Understanding the diversity patterns of marine meiofauna is critical in a changing world. Methods: In this study, we investigate if there is seasonal difference in meiofaunal assemblage composition and diversity along 1 year and if the marine seascapes dynamics (water masses with particular biogeochemical features, characterized by temperature, salinity, absolute dynamic topography, chromophoric dissolved organic material, chlorophyll-a, and normalized fluorescent line height), rainfall, and sediment parameters (total organic matter, carbonate, carbohydrate, protein, lipids, protein-to-carbohydrate, carbohydrate-to-lipids, and biopolymeric carbon) affect significatively meiofaunal diversity at a tropical sandy beach. We tested two hypotheses here: (i) meiofaunal diversity is higher during warmer months and its composition changes significatively among seasons along a year at a tropical sandy beach, and (ii) meiofaunal diversity metrics are significantly explained by marine seascapes characteristics and sediment parameters. We used metabarcoding (V9 hypervariable region from 18S gene) from sediment samples to assess the meiofaunal assemblage composition and diversity (phylogenetic diversity and Shannon's diversity) over a period of 1 year. Results: Meiofauna was dominated by Crustacea (46% of sequence reads), Annelida (28% of sequence reads) and Nematoda (12% of sequence reads) in periods of the year with high temperatures (>25 °C), high salinity (>31.5 ppt), and calm waters. Our data support our initial hypotheses revealing a higher meiofaunal diversity (phylogenetic and Shannon's Diversity) and different composition during warmer periods of the year. Meiofaunal diversity was driven by a set of multiple variables, including biological variables (biopolymeric carbon) and organic matter quality (protein content, lipid content, and carbohydrate-to-lipid ratio).

Contrasting Disease Progression, Microglia Reactivity, Tolerance, and Resistance to Toxoplasma gondii Infection in Two Mouse Strains.

Our study investigated the innate immune response to Toxoplasma gondii infection by assessing microglial phenotypic changes and sickness behavior as inflammatory response markers post-ocular tachyzoite instillation. Disease progression in Swiss albino mice was compared with the previously documented outcomes in BALB/c mice using an identical ocular route and parasite burden (2 × 105 tachyzoites), with saline as the control. Contrary to expectations, the Swiss albino mice displayed rapid, lethal disease progression, marked by pronounced sickness behaviors and mortality within 11-12 days post-infection, while the survivors exhibited no apparent signs of infection. Comparative analysis revealed the T. gondii-infected BALB/c mice exhibited reduced avoidance of feline odors, while the infected Swiss albino mice showed enhanced avoidance responses. There was an important increase in microglial cells in the dentate gyrus molecular layer of the infected Swiss albino mice compared to the BALB/c mice and their respective controls. Hierarchical cluster and discriminant analyses identified three microglial morphological clusters, differentially affected by T. gondii infection across strains. The BALB/c mice exhibited increased microglial branching and complexity, while the Swiss albino mice showed reduced shrunken microglial arbors, diminishing their morphological complexity. These findings highlight strain-specific differences in disease progression and inflammatory regulation, indicating lineage-specific mechanisms in inflammatory responses, tolerance, and resistance. Understanding these elements is critical in devising control measures for toxoplasmosis.

Anterior cruciate ligament primary repair revision rates are increased in skeletally mature patients under the age of 21 compared to reconstruction, while adults (>21 years) show no significant difference: A systematic review and meta-analysis.

PURPOSE: To evaluate the impact of age as a risk factor on the revision rates of anterior cruciate ligament (ACL) primary repair (ACLPR), dynamic intraligamentary stabilization (DIS) and bridge-enhanced ACL restoration (BEAR) compared to ACL reconstruction (ACLR). METHODS: A systematic literature search was performed for comparative studies comparing outcomes for ACLPR, DIS or BEAR to ACLR. A random-effects meta-analysis was performed to assess nondifferentiated and age-differentiated (skeletally mature patients ≤21 and >21 years) ACL revision and reoperation risk, as well as results for subjective outcomes. Methodological study quality was assessed using the Risk of Bias Tool 2.0c and Methodological Index for Nonrandomized Studies tools. RESULTS: A total of 12 studies (n = 1277) were included. ACLR demonstrated a lower nonage-stratified revision risk at 2 years versus ACLPR, DIS and BEAR, but a similar revision risk at 5 years when compared to DIS. However, an age-stratified analysis demonstrated a significantly increased ACLPR revision risk as compared to ACLR in skeletally mature patients ≤21 years of age (risk ratios [RR], 6.33; 95% confidence interval [CI], 1.18-33.87, p = 0.03), while adults (>21 years) showed no significant difference between groups (RR, 1.48; 95% CI, 0.25-8.91, n.s.). Furthermore, DIS reoperation rates were significantly higher than respective ACLR rates (RR, 2.22; 95% CI, 1.35-3.65, p = 0.002), whereas BEAR (RR, 1.07; 95% CI, 0.41-2.75, n.s.) and ACLPR (RR, 0.81; 95% CI, 0.21-3.09, n.s.) showed no differences. IKDC scores were equivalent for all techniques. However, ACLPR exhibited significantly better FJS (mean difference, 11.93; 95% CI, 6.36-17.51, p < 0.0001) and Knee injury and Osteoarthritis Outcome Score Symptoms (mean difference, 3.01; 95% CI, 0.42-5.60, p = 0.02), along with a lower Tegner activity reduction. CONCLUSIONS: ACLPR in skeletally mature patients ≤21 years of age is associated with up to a six-fold risk increase for ACL revision surgery compared to ACLR; however, adults (>21 years) present no significant difference. Based on the current data, age emerges as a crucial risk factor and should be considered when deciding on the appropriate treatment option in proximal ACL tears. LEVEL OF EVIDENCE: Level III.

Type of calcineurin inhibitor and long-term outcomes following liver transplantation in patients with primary biliary cholangitis - an ELTR study.

Background & Aims: Tacrolimus has been associated with recurrence of primary biliary cholangitis (PBC) after liver transplantation (LT), which in turn may reduce survival. This study aimed to assess the association between the type of calcineurin inhibitor used and long-term outcomes following LT in patients with PBC. Methods: Survival analyses were used to assess the association between immunosuppressive drugs and graft or patient survival among adult patients with PBC in the European Liver Transplant Registry. Patients who received a donation after brain death graft between 1990 and 2021 with at least 1 year of event-free follow-up were included. Results: In total, 3,175 patients with PBC were followed for a median duration of 11.4 years (IQR 5.9-17.9) after LT. Tacrolimus (Tac) was registered in 2,056 (64.8%) and cyclosporin in 819 (25.8%) patients. Following adjustment for recipient age, recipient sex, donor age, and year of LT, Tac was not associated with higher risk of graft loss (adjusted hazard ratio [aHR] 1.07, 95% CI 0.92-1.25, p = 0.402) or death (aHR 1.06, 95% CI 0.90-1.24, p = 0.473) over cyclosporin. In this model, maintenance mycophenolate mofetil (MMF) was associated with a lower risk of graft loss (aHR 0.72, 95% CI 0.60-0.87, p <0.001) or death (aHR 0.72, 95% CI 0.59-0.87, p <0.001), while these risks were higher with use of steroids (aHR 1.31, 95% CI 1.13-1.52, p <0.001, and aHR 1.34, 95% CI 1.15-1.56, p <0.001, respectively). Conclusions: In this large LT registry, type of calcineurin inhibitor was not associated with long-term graft or recipient survival, providing reassurance regarding the use of Tac post LT in the population with PBC. Patients using MMF had a lower risk of graft loss and death, indicating that the threshold for combination treatment with Tac and MMF should be low. Impact and implications: This study investigated the association between immunosuppressive drugs and the long-term survival of patients with primary biliary cholangitis (PBC) following donation after brain death liver transplantation. While tacrolimus has previously been related to a higher risk of PBC recurrence, the type of calcineurin inhibitor was not related to graft or patient survival among patients transplanted for PBC in the European Liver Transplant Registry. Additionally, maintenance use of mycophenolate was linked to lower risks of graft loss and death, while these risks were higher with maintenance use of steroids. Our findings should provide reassurance for physicians regarding the continued use of Tac after liver transplantation in the population with PBC, and suggest potential benefit from combination therapy with mycophenolate.

Gut membrane proteins as candidate antigens for immunization of mice against the tick Amblyomma sculptum.

Amblyomma sculptum is widely distributed in Brazil and is the main vector of Rickettsia rickettsii, the causative agent of the Brazilian spotted fever (BSF). Tick gut proteins play an essential role in blood feeding, digestion, and protection of gut epithelium. Therefore, many of these were investigated as potential vaccine targets for tick-control strategies. The present study aimed to select transcripts corresponding to putative immunogenic proteins in the A. sculptum gut epithelial membrane, produce recombinant proteins and evaluate them as antigens against A. sculptum infestations. Three gut proteins - AsMucin, AsAPP, and AsLAMP - and a chimeric protein (rAsChimera) based on 22 peptides containing putative B cell epitopes from seven different gut proteins were evaluated as anti-A. sculptum antigens. Mice immunizations revealed that all recombinant targets elicited humoral response with significantly increased IgG levels compared to controls. For rAsChimera, IgG levels remained significantly higher than controls up to 75 days after the end of the immunization. Challenge trials revealed that vaccination with the chimeric protein was the most effective against A. sculptum, inducing 100 % nymph mortality and reaching 80.8 % efficacy against females. The other three proteins did not induce relevant protection, as AsAPP had only 26.6 % efficacy, whereas AsMucin and AsLAMP induced no protection. These data indicate that targeting gut protein immunogenic regions may be an effective strategy for a vaccine formulation againstA. sculptum.

Bis-sulfonamido-2-phenylbenzoxazoles Validate the GroES/EL Chaperone System as a Viable Antibiotic Target.

We recently reported on small-molecule inhibitors of the GroES/GroEL chaperone system as potential antibiotics against Escherichia coli and the ESKAPE pathogens but were unable to establish GroES/GroEL as the cellular target, leading to cell death. In this study, using two of our most potent bis-sulfonamido-2-phenylbenzoxazoles (PBZs), we established the binding site of the PBZ molecules using cryo-EM and found that GroEL was the cellular target responsible for the mode of action. Cryo-EM revealed that PBZ1587 binds at the GroEL ring-ring interface (RRI). A cellular reporter assay confirmed that PBZ1587 engaged GroEL in cells, but cellular rescue experiments showed potential off-target effects. This prompted us to explore a closely related analogue, PBZ1038, which is also bound to the RRI. Biochemical characterization showed potent inhibition of Gram-negative chaperonins but much lower potency of chaperonin from a Gram-positive organism, Enterococcus faecium. A cellular reporter assay showed that PBZ1038 also engaged GroEL in cells and that the cytotoxic phenotype could be rescued by a chromosomal copy of E. faecium GroEL/GroES or by expressing a recalcitrant RRI mutant. These data argue that PBZ1038's antimicrobial action is exerted through inhibition of GroES/GroEL, validating this chaperone system as an antibiotic target.

Outcomes and performance following posteromedial elbow débridement in major league baseball players.

BACKGROUND: Overhead athletes are particularly susceptible to elbow valgus extension overload syndrome and development of pathologic changes in the posteromedial elbow. Though arthroscopic débridement/osteophyte resection is frequently performed, few studies have analyzed the outcomes of this procedure and none have specifically addressed professional level athletes. HYPOTHESIS: We hypothesized that following posteromedial elbow débridement, Major League Baseball (MLB) pitchers would exhibit a higher rate of ulnar collateral ligament (UCL) reconstruction than baseline incidence in the existing literature, along with a decline in pitching performance. METHODS: Using publicly accessible websites, MLB athletes undergoing posteromedial elbow débridement from 2007 to 2022 were identified. Demographic information, procedure details, return to play (RTP) information, return to the disabled/injured list (DL/IL), subsequent UCL reconstruction, and pitching statistics were analyzed. Pitching performance metrics included earned runs average, walks plus hits per innings pitched, innings pitched, and fastball velocity. RESULTS: A total of 39 MLB players, including 26 pitchers, were included. Within the first three seasons after surgery, 82.1% (n = 32) of players returned to play at the MLB level at a mean time of 176.1 ± 69 days. Pitchers exhibited a RTP rate of 76.9% (n = 20) at 175.8 ± 16 days. A total of 38.5% (n = 10) of pitchers returned to the DL/IL for elbow-related issues within three seasons. Subsequent UCL reconstruction was seen only in pitchers, with a frequency of 19.2% (n = 5). No statistically significant differences between single season preoperative/postoperative pitching metrics were identified. A small but significant (P < .05) decrease in fastball velocity (94.4 vs. 92.84; P = .02) was observed over a three-season comparison. CONCLUSION: Contrary to our hypothesis, this study demonstrates that posteromedial elbow débridement is a viable surgery in MLB athletes, with RTP rate of 82.1% and no increase in rate of UCL reconstruction. Furthermore, there was no significant difference in single season preoperative and postoperative statistical pitching performance. However, over three years postoperatively, there was a 38.5% rate of return to the DL/IL for ongoing elbow ailment and a significant decrease in pitch velocity, raising some concern over the longevity of postoperative improvements.

Evaluating the factor structure and measurement invariance of the 20-item short version of the UPPS-P Impulsive Behavior Scale across multiple countries, languages, and gender identities.

The UPPS-P Impulsive Behavior Model and the various psychometric instruments developed and validated based on this model are well established in clinical and research settings. However, evidence regarding the psychometric validity, reliability, and equivalence across multiple countries of residence, languages, or gender identities, including gender-diverse individuals, is lacking to date. Using data from the International Sex Survey (N = 82,243), confirmatory factor analyses and measurement invariance analyses were performed on the preestablished five-factor structure of the 20-item short version of the UPPS-P Impulsive Behavior Scale to examine whether (a) psychometric validity and reliability and (b) psychometric equivalence hold across 34 country-of-residence-related, 22 language-related, and three gender-identity-related groups. The results of the present study extend the latter psychometric instrument's well-established relevance to 26 countries, 13 languages, and three gender identities. Most notably, psychometric validity and reliability were evidenced across nine novel translations included in the present study (i.e., Croatian, English, German, Hebrew, Korean, Macedonian, Polish, Portuguese-Portugal, and Spanish-Latin American) and psychometric equivalence was evidenced across all three gender identities included in the present study (i.e., women, men, and gender-diverse individuals).

Measurement of the mandibular canal and mandibular incisive canal using cone beam tomography in adults from South Brazil.

PURPOSE: To identify and measure the distance from the dental apices to the mandibular (MC) and mandibular incisive (MIC) canals, the diameter of the MC and the distances of the mental foramen (MF). METHODS: In this retrospective study, cone-beam computed tomography scans of 144 adult patients (males and females) from a dental school in South Brazil were evaluated. Cross-sections were selected on the MC and the MIC paths, perpendicular to the mandibular base, and measurements were taken from the dental apices to the mandibular cortices. The measurement and location of the mandibular and mental foramen on both sides were compared. Paired t-tests compared sides, while Student's t-tests compared sexes (P < 0.05). RESULTS: The distance from the dental apices to the upper wall of the MC was closest in the third molar and farthest in the central incisor region. In both sexes and sides, the path of the MC is in most cases lingually in the molar regions and moves to the buccal region from the second premolar. The MF emerges in the regions between the premolars or near the second premolar. CONCLUSION: The results of this study highlight the importance of evaluating specific individual characteristics of a given population.

Locus coeruleus noradrenaline depletion and its differential impact on CO2-induced panic and hyperventilation in male and female mice.

CO2 exposure has been used to investigate the panicogenic response in patients with panic disorder. These patients are more sensitive to CO2, and more likely to experience the "false suffocation alarm" which triggers panic attacks. Imbalances in locus coeruleus noradrenergic (LC-NA) neurotransmission are responsible for psychiatric disorders, including panic disorder. These neurons are sensitive to changes in CO2/pH. Therefore, we investigated if LC-NA neurons are differentially activated after severe hypercapnia in mice. Further, we evaluated the participation of LC-NA neurons in ventilatory and panic-like escape responses induced by 20% CO2 in male and female wild type mice and two mouse models of altered LC-NA synthesis. Hypercapnia activates the LC-NA neurons, with males presenting a heightened level of activation. Mutant males lacking or with reduced LC-NA synthesis showed hypoventilation, while animals lacking LC noradrenaline present an increased metabolic rate compared to wild type in normocapnia. When exposed to CO2, males lacking LC noradrenaline showed a lower respiratory frequency compared to control animals. On the other hand, females lacking LC noradrenaline presented a higher tidal volume. Nevertheless, no change in ventilation was observed in either sex. CO2 evoked an active escape response. Mice lacking LC noradrenaline had a blunted jumping response and an increased freezing duration compared to the other groups. They also presented fewer racing episodes compared to wild type animals, but not different from mice with reduced LC noradrenaline. These findings suggest that LC-NA has an important role in ventilatory and panic-like escape responses elicited by CO2 exposure in mice.

Structural insights into the regulation of RyR1 by S100A1.

S100A1, a small homodimeric EF-hand Ca2+-binding protein (~21 kDa), plays an important regulatory role in Ca2+ signaling pathways involved in various biological functions including Ca2+ cycling and contractile performance in skeletal and cardiac myocytes. One key target of the S100A1 interactome is the ryanodine receptor (RyR), a huge homotetrameric Ca2+ release channel (~2.3 MDa) of the sarcoplasmic reticulum. Here, we report cryoelectron microscopy structures of S100A1 bound to RyR1, the skeletal muscle isoform, in absence and presence of Ca2+. Ca2+-free apo-S100A1 binds beneath the bridging solenoid (BSol) and forms contacts with the junctional solenoid and the shell-core linker of RyR1. Upon Ca2+-binding, S100A1 undergoes a conformational change resulting in the exposure of the hydrophobic pocket known to serve as a major interaction site of S100A1. Through interactions of the hydrophobic pocket with RyR1, Ca2+-bound S100A1 intrudes deeper into the RyR1 structure beneath BSol than the apo-form and induces sideways motions of the C-terminal BSol region toward the adjacent RyR1 protomer resulting in tighter interprotomer contacts. Interestingly, the second hydrophobic pocket of the S100A1-dimer is largely exposed at the hydrophilic surface making it prone to interactions with the local environment, suggesting that S100A1 could be involved in forming larger heterocomplexes of RyRs with other protein partners. Since S100A1 interactions stabilizing BSol are implicated in the regulation of RyR-mediated Ca2+ release, the characterization of the S100A1 binding site conserved between RyR isoforms may provide the structural basis for the development of therapeutic strategies regarding treatments of RyR-related disorders.