Posttranslational Modifications Mediate the Structural Diversity of Tauopathy Strains.

Tau aggregation into insoluble filaments is the defining pathological hallmark of tauopathies. However, it is not known what controls the formation and templated seeding of strain-specific structures associated with individual tauopathies. Here, we use cryo-electron microscopy (cryo-EM) to determine the structures of tau filaments from corticobasal degeneration (CBD) human brain tissue. Cryo-EM and mass spectrometry of tau filaments from CBD reveal that this conformer is heavily decorated with posttranslational modifications (PTMs), enabling us to map PTMs directly onto the structures. By comparing the structures and PTMs of tau filaments from CBD and Alzheimer's disease, it is found that ubiquitination of tau can mediate inter-protofilament interfaces. We propose a structure-based model in which cross-talk between PTMs influences tau filament structure, contributing to the structural diversity of tauopathy strains. Our approach establishes a framework for further elucidating the relationship between the structures of polymorphic fibrils, including their PTMs, and neurodegenerative disease.

Recent Thymic Emigrants Require RBPJ-Dependent Notch Signaling to Transition into Functionally Mature Naive T Cells.

Recent thymic emigrant (RTE) cells are nascent T cells that continue their post-thymic maturation in the periphery and dominate T cell immune responses in early life and in adults having undergone lymphodepletion regimens. However, the events that govern their maturation and their functionality as they transition to mature naive T cells have not been clearly defined. Using RBPJind mice, we were able to identify different stages of RTE maturation and interrogate their immune function using a T cell transfer model of colitis. As CD45RBlo RTE cells mature, they transition through a CD45RBint immature naive T (INT) cell population that is more immunocompetent but shows a bias toward IL-17 production at the expense of IFN-γ. Additionally, the levels of IFN-γ and IL-17 produced in INT cells are highly dependent on whether Notch signals are received during INT cell maturation or during their effector function. IL-17 production by INT cells showed a total requirement for Notch signaling. Loss of Notch signaling at any stage of INT cells resulted in an impaired colitogenic effect of INT cells. RNA sequencing of INT cells that had matured in the absence of Notch signals showed a reduced inflammatory profile compared with Notch-responsive INT cells. Overall, we have elucidated a previously unknown INT cell stage, revealed its intrinsic bias toward IL-17 production, and demonstrated a role for Notch signaling in INT cell peripheral maturation and effector function in the context of a T cell transfer model of colitis.

Salmonella Vitkin Outbreak Associated with Bearded Dragons, Canada and United States, 2020-2022.

We identified 2 cases of Salmonella enterica serovar Vitkin infection linked by whole-genome sequencing in infants in Ontario, Canada, during 2022. Both households of the infants reported having bearded dragons as pets. The outbreak strain was also isolated from an environmental sample collected from a patient's bearded dragon enclosure. Twelve cases were detected in the United States, and onset dates occurred during March 2021-September 2022 (isolates related to isolates from Canada within 0-9 allele differences by core-genome multilocus sequence typing). Most US patients (66.7%) were <1 year of age, and most (72.7%) had reported bearded dragon exposure. Hospitalization was reported for 5 (38.5%) of 13 patients. Traceback of bearded dragons identified at least 1 potential common supplier in Southeast Asia. Sharing rare serovar information and whole-genome sequencing data between Canada and the United States can assist in timely identification of outbreaks, including those that might not be detected through routine surveillance.

Assessing Endoscopic Response in Locally Advanced Rectal Cancer Treated with Total Neoadjuvant Therapy: Development and Validation of a Highly Accurate Convolutional Neural Network.

BACKGROUND: Rectal tumors display varying degrees of response to total neoadjuvant therapy (TNT). We evaluated the performance of a convolutional neural network (CNN) in interpreting endoscopic images of either a non-complete response to TNT or local regrowth during watch-and-wait surveillance. METHODS: Endoscopic images from stage II/III rectal cancers treated with TNT from 2012 to 2020 at a single institution were retrospectively reviewed. Images were labelled as Tumor or No Tumor based on endoscopy timing (before, during, or after treatment) and the tumor's endoluminal response. A CNN was trained using ResNet-50 architecture. The area under the curve (AUC) was analyzed during training and for two test sets. The main test set included images of tumors treated with TNT. The other contained images of local regrowth. The model's performance was compared to sixteen surgeons and surgical trainees who evaluated 119 images for evidence of tumor. Fleiss' kappa was calculated by respondent experience level. RESULTS: A total of 2717 images from 288 patients were included; 1407 (51.8%) contained tumor. The AUC was 0.99, 0.98, and 0.92 for training, main test, and local regrowth test sets. The model performed on par with surgeons of all experience levels for the main test set. Interobserver agreement was good ( k = 0.71-0.81). All groups outperformed the model in identifying tumor from images of local regrowth. Interobserver agreement was fair to moderate ( k = 0.24-0.52). CONCLUSIONS: A highly accurate CNN matched the performance of colorectal surgeons in identifying a noncomplete response to TNT. However, the model demonstrated suboptimal accuracy when analyzing images of local regrowth.

Evaluation of vaginal microbiome equilibrium states identifies microbial parameters linked to resilience after menses and antibiotic therapy.

The vaginal microbiome (VMB) is a complex microbial community that is closely tied to reproductive health. Optimal VMB communities have compositions that are commonly defined by the dominance of certain Lactobacillus spp. and can remain stable over time or transition to non-optimal states dominated by anaerobic bacteria and associated with bacterial vaginosis (BV). The ability to remain stable or undergo transitions suggests a system with either single (mono-stable) or multiple (multi-stable) equilibrium states, though factors that contribute to stability have been difficult to determine due to heterogeneity in microbial growth characteristics and inter-species interactions. Here, we use a computational model to determine whether differences in microbial growth and interaction parameters could alter equilibrium state accessibility and account for variability in community composition after menses and antibiotic therapies. Using a global uncertainty and sensitivity analysis that captures parameter sets sampled from a physiologically relevant range, model simulations predicted that 79.7% of microbial communities were mono-stable (gravitate to one composition type) and 20.3% were predicted to be multi-stable (can gravitate to more than one composition type, given external perturbations), which was not significantly different from observations in two clinical cohorts (HMP cohort, 75.2% and 24.8%; Gajer cohort, 78.1% and 21.9%, respectively). The model identified key microbial parameters that governed equilibrium state accessibility, such as the importance of non-optimal anaerobic bacteria interactions with Lactobacillus spp., which is largely understudied. Model predictions for composition changes after menses and antibiotics were not significantly different from those observed in clinical cohorts. Lastly, simulations were performed to illustrate how this quantitative framework can be used to gain insight into the development of new combinatorial therapies involving altered prebiotic and antibiotic dosing strategies. Altogether, dynamical models could guide development of more precise therapeutic strategies to manage BV.

Examining the Intersection of Ethnoracial Disparities and HIV Status in Substance Use Risks among U.S. Adults.

Black/African American and Hispanic Americans experience significant HIV-related disparities. Substance use might be a contributing factor to these disparities, but there is limited research on this topic. This study investigated various substance use risks by HIV status and race/ethnicity (Black, Hispanic, White) among U.S. adults. We used data from the 2005-2019 National Survey on Drug Use and Health (N = 541,921). In each racial/ethnic group, the prevalence rates of past-year and past-month tobacco, alcohol, cannabis, and cocaine use, and past-year alcohol and illicit drug use disorders were estimated by HIV status. A series of logistic regressions with the interaction term of HIV x race/ethnicity were performed to examine race/ethnicity's moderating effect on the HIV-substance use associations, while controlling for sociodemographic factors and survey year. Moderation analysis showed that HIV status's association with the risks of past-year tobacco use (AOR = 1.67, 95% CI = 1.01-2.75), past-year cocaine use (AOR = 3.80, 95% CI = 1.91-7.57), past-month cocaine use (AOR = 5.34, 95% CI = 2.10-13.60), and past-year alcohol use disorder (AOR = 2.52, 95% CI = 1.29-4.92) differed significantly between Black and White adults. Between the Hispanic and White groups, HIV status's association with the risks of past-year alcohol use (AOR = 2.00, 95% CI = 1.09-3.69), past-year cocaine use (AOR = 2.40, 95% CI = 1.06-5.39), and past-month cocaine use (AOR = 3.69, 95% CI = 1.36-10.02) also differed significantly. It is well-established that individuals with HIV face an elevated risk of substance use. Our study added valuable insights by highlighting that this phenomenon is particularly more significant among Black and Hispanic adults for several substances when compared to White adults. Implications for practice are discussed.

Realization of the T Lineage Program Involves GATA-3 Induction of Bcl11b and Repression of Cdkn2b Expression.

The zinc-finger transcription factor GATA-3 plays a crucial role during early T cell development and also dictates later T cell differentiation outcomes. However, its role and collaboration with the Notch signaling pathway in the induction of T lineage specification and commitment have not been fully elucidated. We show that GATA-3 deficiency in mouse hematopoietic progenitors results in an early block in T cell development despite the presence of Notch signals, with a failure to upregulate Bcl11b expression, leading to a diversion along a myeloid, but not a B cell, lineage fate. GATA-3 deficiency in the presence of Notch signaling results in the apoptosis of early T lineage cells, as seen with inhibition of CDK4/6 (cyclin-dependent kinases 4 and 6) function, and dysregulated cyclin-dependent kinase inhibitor 2b (Cdkn2b) expression. We also show that GATA-3 induces Bcl11b, and together with Bcl11b represses Cdkn2b expression; however, loss of Cdkn2b failed to rescue the developmental block of GATA-3-deficient T cell progenitor. Our findings provide a signaling and transcriptional network by which the T lineage program in response to Notch signals is realized.

Vascular Reconstruction and Limb Loss in Military Tibial Artery Injuries.

BACKGROUND: Selective operative management of injuries to the tibial arteries is controversial, with the necessity of revascularization in the face of multiple tibial arteries debated. Tibial artery injuries are frequently encountered in military trauma, but revascularization practices and outcomes are poorly defined. We aimed to investigate associations between the number of injured vessels and reconstruction and limb loss rates in military casualties with tibial arterial trauma. METHODS: A US military database of lower extremity vascular injuries from Iraq and Afghanistan (2004-2012) was queried for limbs sustaining at least 1 tibial artery injury. Injury, intervention characteristics, and limb outcomes were analyzed by the number of tibial arteries injured (1, T1; 2, T2; 3, T3). RESULTS: Two hundred twenty one limbs were included (194 T1, 22 T2, 5 T3). The proportions with concomitant venous, orthopedic, nerve, or proximal arterial injuries were similar between groups. Arterial reconstruction (versus ligation) was performed in 29% of T1, 63% of T2, and universally in T3 limbs (P < 0.001). Arterial reconstruction was via vein graft (versus localized repair) in 62% of T1, 54% of T2, and 80% of T3 (P = 0.59). T3 received greater blood transfusion volume (P = 0.02), and fasciotomy was used universally (versus 34% T1 and 14% T2, P = 0.05). Amputation rates were 23% for T1, 26% for T2, and 60% for T3 (P = 0.16), and amputation was not significantly predicted by arterial ligation in T1 (P = 0.08) or T2 (P = 0.34) limbs. Limb infection was more common in T3 (80%) than in T1 (25%) or T2 (32%, P = 0.02), but other limb complication rates were similar. CONCLUSIONS: In this series of military lower extremity injuries, an increasing number of tibial arteries injured was associated with the increasing use of arterial reconstruction. Limbs with all 3 tibial arteries injured had high rates of complex vascular reconstruction and eventual amputation. Limb loss was not predicted by arterial ligation in 1-vessel and 2-vessel injuries, suggesting that selective reconstruction in these cases is advisable.

Uncialamycin-based antibody-drug conjugates: Unique enediyne ADCs exhibiting bystander killing effect.

Antibody-drug conjugates (ADCs) have emerged as valuable targeted anticancer therapeutics with at least 11 approved therapies and over 80 advancing through clinical trials. Enediyne DNA-damaging payloads represented by the flagship of this family of antitumor agents, N-acetyl calicheamicin [Formula: see text], have a proven success track record. However, they pose a significant synthetic challenge in the development and optimization of linker drugs. We have recently reported a streamlined total synthesis of uncialamycin, another representative of the enediyne class of compounds, with compelling synthetic accessibility. Here we report the synthesis and evaluation of uncialamycin ADCs featuring a variety of cleavable and noncleavable linkers. We have discovered that uncialamycin ADCs display a strong bystander killing effect and are highly selective and cytotoxic in vitro and in vivo.

Perspectives on the comparative benefits of body-powered and myoelectric upper limb prostheses.

BACKGROUND: Patient access to body-powered and myoelectric upper limb prostheses in the United States is often restricted by a healthcare system that prioritizes prosthesis prescription based on cost and perceived value. Although this system operates on an underlying assumption that design differences between these prostheses leads to relative advantages and disadvantages of each device, there is limited empirical evidence to support this view. MAIN TEXT: This commentary article will review a series of studies conducted by our research team with the goal of differentiating how prosthesis design might impact user performance on a variety of interrelated domains. Our central hypothesis is that the design and actuation method of body-powered and myoelectric prostheses might affect users' ability to access sensory feedback and account for device properties when planning movements. Accordingly, other domains that depend on these abilities may also be affected. While our work demonstrated some differences in availability of sensory feedback based on prosthesis design, this did not result in consistent differences in prosthesis embodiment, movement accuracy, movement quality, and overall kinematic patterns. CONCLUSION: Collectively, our findings suggest that performance may not necessarily depend on prosthesis design, allowing users to be successful with either device type depending on the circumstances. Prescription practices should rely more on individual needs and preferences than cost or prosthesis design. However, we acknowledge that there remains a dearth of evidence to inform decision-making and that an expanded research focus in this area will be beneficial.

Development and validation of the coffee task: a novel functional assessment for prosthetic grip selection.

BACKGROUND: Lack of standardized assessments that explicitly quantify performance during prosthetic grip selection poses difficulty determining whether efforts to improve the design of multi-grip hands and their control approaches are successful. In this study, we developed and validated a novel assessment of multi-grip prosthetic performance: The Coffee Task. METHODS: Individuals without limb loss completed the Box and Block Test and two versions of the Coffee Task - Continuous and Segmented - with a myoelectric prosthetic emulator. On different days, participants selected prosthetic grips using pattern recognition and trigger control. Outcomes of the Continuous and Segmented Coffee Task were completion time and number of errors, respectively. Two independent raters assessed outcomes of the Coffee Task using video recordings to determine inter-rater reliability. Known-group validity was assessed by comparing outcomes with the emulator to those with an intact limb. Convergent validity was assessed through the correlation of the Coffee Task outcomes and those of the Box and Blocks Test. Responsiveness to changes with practice and control approach were assessed using the standardized response mean (SRM). RESULTS: Inter-rater reliability was high for both versions of the Coffee Task (Intra-class coefficient > 0.981). Coffee Task outcomes were moderately correlated with the Box and Blocks outcomes (|r| ≥ 0.412, p ≤ 0.007). Participants completed the Coffee Task faster with their intact limb than with the emulator (p < 0.001). Both versions of the Coffee Task were responsive to changes with training (SRM ≥ 0.81) but not control approach (SRM ≤ 0.12). CONCLUSIONS: The Coffee Task is reliable, has good known-group and convergent validity, and is responsive to changes due to practice. Future work should assess whether the Coffee Task is feasible and reliable for people with upper limb loss who use multi-grip prostheses.

Implementation of a unilateral hip flexion exosuit to aid paretic limb advancement during inpatient gait retraining for individuals post-stroke: a feasibility study.

BACKGROUND: During inpatient rehabilitation, physical therapists (PTs) often need to manually advance patients' limbs, adding physical burden to PTs and impacting gait retraining quality. Different electromechanical devices alleviate this burden by assisting a patient's limb advancement and supporting their body weight. However, they are less ideal for neuromuscular engagement when patients no longer need body weight support but continue to require assistance with limb advancement as they recover. The objective of this study was to determine the feasibility of using a hip flexion exosuit to aid paretic limb advancement during inpatient rehabilitation post-stroke. METHODS: Fourteen individuals post-stroke received three to seven 1-hour walking sessions with the exosuit over one to two weeks in addition to standard care of inpatient rehabilitation. The exosuit assistance was either triggered by PTs or based on gait events detected by body-worn sensors. We evaluated clinical (distance, speed) and spatiotemporal (cadence, stride length, swing time symmetry) gait measures with and without exosuit assistance during 2-minute and 10-meter walk tests. Sessions were grouped by the assistance required from the PTs (limb advancement and balance support, balance support only, or none) without exosuit assistance. RESULTS: PTs successfully operated the exosuit in 97% of sessions, of which 70% assistance timing was PT-triggered to accommodate atypical gait. Exosuit assistance eliminated the need for manual limb advancement from PTs. In sessions with participants requiring limb advancement and balance support, the average distance and cadence during 2-minute walk test increased with exosuit assistance by 2.2 ± 3.1 m and 3.4 ± 1.9 steps/min, respectively (p < 0.017). In sessions with participants requiring balance support only, the average speed during 10-meter walk test increased with exosuit by 0.07 ± 0.12 m/s (p = 0.042). Clinical and spatiotemporal measures of independent ambulators were similar with and without exosuit (p > 0.339). CONCLUSIONS: We incorporated a unilateral hip flexion exosuit into inpatient stroke rehabilitation in individuals with varying levels of impairments. The exosuit assistance removed the burden of manual limb advancement from the PTs and resulted in improved gait measures in some conditions. Future work will understand how to optimize controller and assistance profiles for this population.

Serial troponin-T and long-term outcomes in suspected acute coronary syndrome.

BACKGROUND: Long-term prognostic implications of serial high-sensitivity troponin concentrations in subjects with suspected acute coronary syndrome are unknown. METHODS AND RESULTS: Individuals with a first diagnosis of myocardial infarction, unstable angina, observation for suspected myocardial infarction, or chest pain from 2012 through 2019 who underwent two high-sensitivity troponin-T (hsTnT) measurements 1-7 h apart were identified through Danish national registries. Absolute and relative risks for death at days 0-30 and 31-365, stratified for whether subjects had normal or elevated hsTnT concentrations, and whether these concentrations changed by <20%, > 20 to 50%, or >50% in either direction from first to second measurement, were calculated through multivariable logistic regression with average treatment effect modeling. Of the 28 902 individuals included, 2.8% had died at 30 days, whereas 4.9% of those who had survived the first 30 days died between days 31-365. The standardized risk of death was highest among subjects with two elevated hsTnT concentrations (0-30 days: 4.3%, 31-365 days: 7.2%). In this group, mortality was significantly higher in those with a > 20 to 50% or >50% rise from first to second measurement, though only at 30 days. The risk of death was very low in subjects with two normal hsTnT concentrations (0-30 days: 0.1%, 31-365 days: 0.9%) and did not depend on relative or absolute changes between measurements. CONCLUSIONS: Individuals with suspected acute coronary syndrome and two consecutively elevated hsTnT concentrations consistently had the highest risk of death. Mortality was very low in subjects with two normal hsTnT concentrations, irrespective of changes between measurements.

Computed tomography dose index determination in dose modulation prospectively involving the third-generation iterative reconstruction and noise index.

PURPOSE: Optimizing CT protocols is challenging in the presence of automatic dose modulation because the CT dose index (CTDIvol) at different patient sizes is unknown to the operator. The task is more difficult when both the image quality index and iterative reconstruction prospectively affect the dose determination. It is of interest in practice to be informed of the CTDIvol during the protocol initialization and evaluation. It was our objective to obtain a predictive relationship between CTDIvol, the image quality index, and iterative reconstruction strength at various patient sizes. METHODS: Dose modulation data were collected on a GE Revolution 256-slice scanner utilizing a Mercury phantom and selections of the noise index (NI) from 8 to 17, the third generation iterative reconstruction (ASIR-V) from 0% to 80%, and phantom diameters from 16 to 36 cm. The fixed parameters were 120 kVp, a pitch of .984, and a collimation of 40 mm with a primary slice width of 2.5 mm. The CTDIvol per diameter was based on the average tube current over three adjacent slices (same or similar diameter) multiplied by a conversion factor between the average mA of the series and the reported CTDIvol. The relationship between CTDIvol, NI, and ASIR-V for each diameter was fitted with a 2nd order polynomial of ASIR-V multiplied by a power law of NI. RESULTS: The ASIR-V fit parameters versus diameter followed a Lorentz function while the NI exponent versus diameter followed an exponential growth function. The CTDIvol predictions were accurate within 15% compared to phantom results on a separate GE Revolution. For clinical relevance, the phantom diameter was converted to an abdomen or chest equivalent diameter and was well matched to patient data. CONCLUSION: The fitted relationship for CTDIvol. for given values of NI and ASIR-V blending for a range of phantom sizes was a good match to phantom and patient data. The results can be of direct help for selecting adequate parameters in CT protocol development.

Piconewton Forces Mediate GAIN Domain Dissociation of the Latrophilin-3 Adhesion GPCR.

Latrophilins are adhesion G-protein coupled receptors (aGPCRs) that control excitatory synapse formation. Most aGPCRs, including latrophilins, are autoproteolytically cleaved at their GPCR-autoproteolysis inducing (GAIN) domain, but the two resulting fragments remain noncovalently associated on the cell surface. Force-mediated dissociation of the fragments is thought to activate G-protein signaling, but how this mechanosensitivity arises is poorly understood. Here, we use magnetic tweezer assays to show that physiologically relevant forces in the 1-10 pN range lead to dissociation of the latrophilin-3 GAIN domain on the seconds-to-minutes time scale, compared to days in the absence of force. In addition, we find that the GAIN domain undergoes large changes in length in response to increasing mechanical load. These data are consistent with a model in which a force-sensitive equilibrium between compact and extended GAIN domain states precedes dissociation, suggesting a mechanism by which latrophilins and other aGPCRs may mediate mechanically induced signal transduction.

Technical and relational process in MI sessions with a sample of Hispanic/Latinx adults who engage in heavy drinking: A latent growth mediation model.

The current study tests the Motivational Interviewing (MI) technical and relational hypotheses in a sample of Hispanic/Latinx adults (N = 276) who engage in heavy alcohol consumption. MI causal theory hypothesizes that therapist use of MI consistent skills (i.e., technical hypothesis) and embodiment of the MI Spirit (i.e., relational hypothesis) will elicit client change talk, which is a putative mechanism of positive client outcome after the session. We tested these associations in a rigorous parallel process latent growth curve mediation modeling framework. The data are from a completed randomized clinical trial of a culturally-adapted (CAMI) versus un-adapted MI targeting hazardous alcohol use and consequences. Results. The unconditional growth models for the mediator (i.e., proportion of change talk relative to sustain talk) and two study outcomes (i.e., percent of heavy drinking days; alcohol-related consequences) showed a linear effect over a 12-month period with a slower rate of growth at later timepoints. Contrary to expectations, the latent growth mediation models did not show relationships between MI-consistent skills (i.e., technical predictor) or latent MI Spirit (i.e., relational indicator) and the slope factor for proportion change talk. The slope factor for proportion change talk was also not associated with the slope factors for percent heavy drinking and consequences over follow-up. Conclusions. In this novel population for MI process analysis, the technical and relational hypotheses were not supported. Studies that are exploratory may be needed to further investigate the causal model in populations that are not often represented in MI process research.

Targeted Lysosomal Degradation of Secreted and Cell Surface Proteins through the LRP-1 Pathway.

Protein dysregulation has been characterized as the cause of pathogenesis in many different diseases. For proteins lacking easily druggable pockets or catalytically active sites, targeted protein degradation is an attractive therapeutic approach. While several methods for targeted protein degradation have been developed, there remains a demand for lower molecular weight molecules that promote efficient degradation of their targets. In this work, we describe the synthesis and validation of a series of heterobifunctional molecules that bind a protein of interest through a small molecule ligand while targeting them to the lysosome using a short gluten peptide that leverages the TG2/LRP-1 pathway. We demonstrate that this approach can be used to effectively endocytose and degrade representative secreted, cell surface, and transmembrane proteins, notably streptavidin, the vitamin B12 receptor, cubilin, and integrin αvß5. Optimization of these prototypical molecules could generate pharmacologically relevant LYTAC agents.

Replication and innate immune responses of two chikungunya virus genotypes in human monocyte-derived macrophages.

Chikungunya virus (CHIKV) is a re-emerging mosquito-borne virus, which causes epidemics of fever, joint pain and rash. There are three genotypes: West African, East/Central/South/Africa (ECSA) and Asian, with the latter two predominant globally. Genotype-specific differences in clinical presentations, virulence and immunopathology have been described. Macrophages are key cells in immune responses against CHIKV. Circulating blood monocytes enter tissue to differentiate into monocyte-derived macrophages (MDMs) in response to CHIKV infection at key replication sites such as lymphoid organs and joints. This study analyses differences in replication and induced immune mediators following infection of MDMs with Asian and ECSA CHIKV genotypes. Primary human MDMs were derived from residual blood donations. Replication of Asian (MY/06/37348) or ECSA (MY/08/065) genotype strains of CHIKV in MDMs was measured by plaque assay. Nineteen immune mediators were measured in infected cell supernatants using multiplexed immunoassay or ELISA. MY/08/065 showed significantly higher viral replication at 24 h post-infection (h p.i.) but induced significantly lower expression of proinflammatory cytokines (CCL-2, CCL-3, CCL-4, RANTES and CXCL-10) and the anti-inflammatory IL-1Ra compared to MY/06/37348. No differences were seen at later time points up to 72 h p.i. During early infection, MY/08/065 induced lower proinflammatory immune responses in MDMs. In vivo, this may lead to poorer initial control of viral infection, facilitating CHIKV replication and dissemination to other sites such as joints. This may explain the consistent past findings that the ECSA genotype is associated with greater viremia and severity of symptoms than the Asian genotype. Knowledge of CHIKV genotype-specific immunopathogenic mechanisms in human MDMs is important in understanding of clinical epidemiology, biomarkers and therapeutics in areas with co-circulation of different genotypes.

Arterial Access Complications Following Percutaneous Femoral Access in 24-Hour Resuscitative Endovascular Balloon Occlusion of the Aorta Survivors.

INTRODUCTION: With the use of resuscitative endovascular balloon occlusion of the aorta (REBOA) comes the potential for vascular access site complications (VASCs) and limb ischemic sequelae. We aimed to determine the prevalence of VASC and associated clinical and technical factors. METHODS: A retrospective cohort analysis of 24-h survivors undergoing percutaneous REBOA via the femoral artery in the American Association for the Surgery of Trauma Aortic Occlusion for Resuscitation in Trauma and Acute care surgery registry between Oct 2013 and Sep 2021 was performed. The primary outcome was VASC, defined as at least one of the following: hematoma, pseudoaneurysm, arteriovenous fistula, arterial stenosis, or the use of patch angioplasty for arterial closure. Associated clinical and procedural variables were examined. Data were analyzed using Fisher exact test, Mann-Whitney-U tests, and linear regression. RESULTS: There were 34 (7%) cases with VASC among 485 meeting inclusion criteria. Hematoma (40%) was the most common, followed by pseudoaneurysm (26%) and patch angioplasty (21%). No differences in demographics or injury/shock severity were noted between cases with and without VASC. The use of ultrasound (US) was protective (VASC, 35% versus no VASC, 51%; P = 0.05). The VASC rate in US cases was 12/242 (5%) versus 22/240 (9.2%) without US. Arterial sheath size >7 Fr was not associated with VASC. US use increased over time (R2 = 0.94, P < 0.001) with a stable rate of VASC (R2 = 0.78, P = 0.61). VASC were associated with limb ischemia (VASC, 15% versus no VASC, 4%; P = 0.006) and arterial bypass procedures (VASC 3% versus no VASC 0%; P < 0.001) but amputation was uncommon (VASC, 3% versus no VASC, 0.4%; P = 0.07). CONCLUSIONS: Percutaneous femoral REBOA had a 7% VASC rate which was stable over time. VASC are associated with limb ischemia but need for surgical intervention and/or amputation is rare. The use of US-guided access appears to be protective against VASC and is recommended for use in all percutaneous femoral REBOA procedures.