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VEXAS is caused by somatic mutations in UBA1 (UBA1mut) and characterized by heterogenous systemic auto-inflammation and progressive hematologic manifestations, meeting criteria for myelodysplastic syndrome (MDS) and plasma cell dyscrasias. The landscape of myeloid-related gene mutations leading to typical clonal hematopoiesis (CH) in these patients is unknown. Retrospectively, we screened 80 VEXAS patients for CH in their peripheral blood (PB) and correlated findings with clinical outcomes in 77. UBA1mutwere most common at hotspot p.M41 (median variant allele frequency/VAF = 75%). Typical CH mutations co-occurred with UBA1mut in 60% of patients, mostly in DNMT3A and TET2, and were not associated with inflammatory or hematologic manifestations. In prospective single-cell proteogenomic sequencing (scDNA), UBA1mutwas the dominant clone, present mostly in branched clonal trajectories. Based on integrated bulk and scDNA analyses, clonality in VEXAS followed two major patterns: with either typical CH preceding UBA1mutselection in a clone (Pattern 1), or occurring as an UBA1mutsubclone or in independent clones (Pattern 2). VAF in PB differed markedly between DNMT3A and TET2 clones (median VAF of 25% vs 1%). DNMT3A and TET2 clones associated with hierarchies representing patterns 1 and 2, respectively. Overall survival for all patients was 60% at 10 years. Transfusion-dependent anemia, moderate thrombocytopenia, and typical CH mutations, each correlated with poor outcome. In VEXAS, UBA1mut cells are the primary cause of systemic inflammation and marrow failure, being a new molecularly defined somatic entity associated with MDS. VEXAS-associated MDS is distinct from classical MDS in its presentation and clinical course.

AbstractIt has been challenging to target mutant KRAS (mKRAS) in colorectal cancer (CRC) and other malignancies. Recent efforts have focused on developing inhibitors blocking molecules essential for KRAS activity. In this regard, SOS1 inhibition has arisen as an attractive approach for mKRAS CRC given its essential role as a guanine nucleotide exchange factor for this GTPase. Here, we demonstrated the translational value of SOS1 blockade in mKRAS CRC. We used CRC patient‐derived organoids (PDOs) as preclinical models to evaluate their sensitivity to SOS1 inhibitor BI3406. A combination of in silico analyses and wet lab techniques was utilized to define potential predictive markers for SOS1 sensitivity and potential mechanisms of resistance in CRC. RNA‐seq analysis of CRC PDOs revealed two groups of CRC PDOs with differential sensitivities to SOS1 inhibitor BI3406. The resistant group was enriched in gene sets involving cholesterol homeostasis, epithelial−mesenchymal transition, and TNF‐α/NFκB signaling. Expression analysis identified a significant correlation between SOS1 and SOS2 mRNA levels (Spearman's ρ 0.56, p < 0.001). SOS1/2 protein expression was universally present with heterogeneous patterns in CRC cells but only minimal to none in surrounding nonmalignant cells. Only SOS1 protein expression was associated with worse survival in patients with RAS/RAF mutant CRC (p = 0.04). We also found that SOS1/SOS2 protein expression ratio >1 by immunohistochemistry (p = 0.03) instead of KRAS mutation (p = 1) was a better predictive marker to BI3406 sensitivity of CRC PDOs, concordant with the significant positive correlation between SOS1/SOS2 protein expression ratio and SOS1 dependency. Finally, we showed that GTP‐bound RAS level underwent rebound even in BI3406‐sensitive PDOs with no change of KRAS downstream effector genes, thus suggesting upregulation of guanine nucleotide exchange factor as potential cellular adaptation mechanisms to SOS1 inhibition. Taken together, our results show that high SOS1/SOS2 protein expression ratio predicts sensitivity to SOS1 inhibition and support further clinical development of SOS1‐targeting agents in CRC.

Background: Clonal hematopoiesis (CH) of indeterminate potential (CHIP) is a risk factor for cardiovascular disease. The relationship between CHIP and coronary microvascular dysfunction (CMD) is unknown. The current study examines the association between CHIP and CH with CMD and the potential relationships in risk for adverse cardiovascular outcomes. Methods: In this retrospective observational study, targeted next-generation sequencing was performed for 177 participants with no coronary artery disease who presented with chest pain and underwent routine coronary functional angiogram. Patients with somatic mutations in leukemia-associated driver genes in hematopoietic stem and progenitor cells were examined; CHIP was considered at a variant allele fraction ≥2%; CH was considered at a variant allele fraction ≥1%. CMD was defined as coronary flow reserve to intracoronary adenosine of ≤2. Major adverse cardiovascular events considered were myocardial infarction, coronary revascularization, or stroke. Results: A total of 177 participants were examined. Mean follow-up was 12±7 years. A total of 17 patients had CHIP and 28 had CH. Cases with CMD (n=19) were compared with controls with no CMD (n=158). Cases were 56±9 years, were 68% women, and had more CHIP (27%; P =0.028) and CH (42%; P =0.001) than controls. CMD was associated with independent risk for major adverse cardiovascular events (hazard ratio, 3.89 [95% CI, 1.21–12.56]; P =0.023), and 32% of this risk was mediated by CH. The risk mediated by CH was ≈0.5× as large as the direct effect of CMD on major adverse cardiovascular events. Conclusions: In humans, we observe patients with CMD are more likely to have CHIP, and nearly one-third of major adverse cardiovascular events in CMD are mediated by CH.

Infectious diseases contribute significantly to the global disease burden. Sensitive and accurate screening methods are some of the most effective means of identifying sources of infection and controlling infectivity. Conventional detecting strategies such as quantitative polymerase chain reaction (qPCR), DNA sequencing, and mass spectrometry typically require bulky equipment and well-trained personnel. Therefore, mass screening of a large population using conventional strategies during pandemic periods often requires additional manpower, resources, and time, which cannot be guaranteed in resource-limited settings. Recently, emerging microfluidic technologies have shown the potential to replace conventional methods in performing point-of-care detection because they are automated, miniaturized, and integrated. By exploiting the spatial separation of detection sites, microfluidic platforms can enable the multiplex detection of infectious diseases to reduce the possibility of misdiagnosis and incomplete diagnosis of infectious diseases with similar symptoms. This review presents the recent advances in microfluidic platforms used for multiplex detection of infectious diseases, including microfluidic immunosensors and microfluidic nucleic acid sensors. As representative microfluidic platforms, lateral flow immunoassay (LFIA) platforms, polymer-based chips, paper-based devices, and droplet-based devices will be discussed in detail. In addition, the current challenges, commercialization, and prospects are proposed to promote the application of microfluidic platforms in infectious disease detection.

Significance Statement Changes in albuminuria and GFR slope are individually used as surrogate end points in clinical trials of CKD progression, and studies have demonstrated that each is associated with treatment effects on clinical end points. In this study, the authors sought to develop a conceptual framework that combines both surrogate end points to better predict treatment effects on clinical end points in Phase 2 trials. The results demonstrate that information from the combined treatment effects on albuminuria and GFR slope improves the prediction of treatment effects on the clinical end point for Phase 2 trials with sample sizes between 100 and 200 patients and duration of follow-up ranging from 1 to 2 years. These findings may help inform design of clinical trials for interventions aimed at slowing CKD progression. Background Changes in log urinary albumin-to-creatinine ratio (UACR) and GFR slope are individually used as surrogate end points in clinical trials of CKD progression. Whether combining these surrogate end points might strengthen inferences about clinical benefit is unknown. Methods Using Bayesian meta-regressions across 41 randomized trials of CKD progression, we characterized the combined relationship between the treatment effects on the clinical end point (sustained doubling of serum creatinine, GFR <15 ml/min per 1.73 m 2 , or kidney failure) and treatment effects on UACR change and chronic GFR slope after 3 months. We applied the results to the design of Phase 2 trials on the basis of UACR change and chronic GFR slope in combination. Results Treatment effects on the clinical end point were strongly associated with the combination of treatment effects on UACR change and chronic slope. The posterior median meta-regression coefficients for treatment effects were −0.41 (95% Bayesian Credible Interval, −0.64 to −0.17) per 1 ml/min per 1.73 m 2 per year for the treatment effect on GFR slope and −0.06 (95% Bayesian Credible Interval, −0.90 to 0.77) for the treatment effect on UACR change. The predicted probability of clinical benefit when considering both surrogates was determined primarily by estimated treatment effects on UACR when sample size was small (approximately 60 patients per treatment arm) and follow-up brief (approximately 1 year), with the importance of GFR slope increasing for larger sample sizes and longer follow-up. Conclusions In Phase 2 trials of CKD with sample sizes of 100–200 patients per arm and follow-up between 1 and 2 years, combining information from treatment effects on UACR change and GFR slope improved the prediction of treatment effects on clinical end points.

AbstractObjectiveTo describe the outcomes of patients undergoing open stapler versus transoral rigid and flexible endoscopic therapies for symptomatic Zenker's diverticulum.Study DesignSingle institution retrospective review.SettingTertiary care academic hospital.MethodsWe retrospectively evaluated the outcomes of 424 consecutive patients who underwent Zenker's diverticulotomy via an open stapler, rigid endoscopic CO2 laser, rigid endoscopic stapler, rigid endoscopic harmonic scalpel, or flexible endoscopic technique from January 2006 to December 2020.ResultsA total of 424 patients (173 females, mean age 73.1 ± 11.2 years) from a single institution were included. A total of 142 patients (33%) underwent endoscopic laser treatment, 33 (8%) underwent endoscopic harmonic scalpel, 92 (22%) underwent endoscopic stapler, 70 (17%) underwent flexible endoscopic, and 87 (20%) underwent open stapler. All open and rigid endoscopic procedures and most of the flexible endoscopic procedures (65%) were performed under general anesthesia. The flexible endoscopic group had a higher percentage of procedure‐related perforation, defined as subcutaneous emphysema or contrast leak on imaging (14.3%). The recurrence rates were higher in the harmonic stapler, flexible endoscopic, and endoscopic stapler groups at 18.2%, 17.1%, and 17.4%, respectively, and lower in the open group (1.1%). Length of hospital stay and return to oral intake were similar among groups.ConclusionThe flexible endoscopic technique was associated with the highest rate of procedure‐related perforation, while the endoscopic stapler had the lowest number of procedural complications. Recurrence rates were higher among the harmonic stapler, flexible endoscopic, and endoscopic stapler groups and lower in the endoscopic laser and open groups. Prospective comparative studies with long‐term follow‐up are needed.

Abstract Decision-makers objectively commit to a definitive choice, yet at the subjective level, human decisions appear to be associated with a degree of certainty. Whether decisions are definitive—concluding in all-or-none choices, or whether the underlying representations are graded, has been unclear. To address this issue, we recorded neural signals directly from the brain while naive human subjects made perceptual decisions. The recordings revealed that each individual’s decisions formed within broadband gamma activity. The gamma activity was graded by decision evidence. Crucially, this analog, grading effect prevailed beyond the time of choice, instead of assuming a switch-like command. The effect was strongest in parietal and premotor cortex, brain regions traditionally implicated in decision-making. These data provide neural evidence for a graded nature of the decision process.

Abstract Through its classic ATP‐dependent ion‐pumping function, basolateral Na/K‐ATPase (NKA) generates the Na + gradient that drives apical Na + reabsorption in the renal proximal tubule (RPT), primarily through the Na + /H + exchanger (NHE3). Accordingly, activation of NKA‐mediated ion transport decreases natriuresis through activation of basolateral (NKA) and apical (NHE3) Na + reabsorption. In contrast, activation of the more recently discovered NKA signaling function triggers cellular redistribution of RPT NKA and NHE3 and decreases Na + reabsorption. We used gene targeting to test the respective contributions of NKA signaling and ion pumping to the overall regulation of RPT Na + reabsorption. Knockdown of RPT NKA in cells and mice increased membrane NHE3 and Na + /HCO 3 − cotransporter (NBCe1A). Urine output and absolute Na + excretion decreased by 65%, driven by increased RPT Na + reabsorption (as indicated by decreased lithium clearance and unchanged glomerular filtration rate), and accompanied by elevated blood pressure. This hyper reabsorptive phenotype was rescued upon crossing with RPT NHE3 −/− mice, confirming the importance of NKA/NHE3 coupling. Hence, NKA signaling exerts a tonic inhibition on Na + reabsorption by regulating key apical and basolateral Na + transporters. This action, lifted upon NKA genetic suppression, tonically counteracts NKA's ATP‐driven function of basolateral Na + reabsorption. Strikingly, NKA signaling is not only physiologically relevant but it also appears to be functionally dominant over NKA ion pumping in the control of RPT reabsorption.

Radiation-induced brain injury (RIBI) is a debilitating sequela after radiotherapy to treat head and neck cancer, and 20 to 30% of patients with RIBI fail to respond to or have contraindications to the first-line treatments of bevacizumab and corticosteroids. Here, we reported a Simon’s minmax two-stage, single-arm, phase 2 clinical trial (NCT03208413) to assess the efficacy of thalidomide in patients with RIBI who were unresponsive to or had contraindications to bevacizumab and corticosteroid therapies. The trial met its primary endpoint, with 27 of 58 patients enrolled showing ≥25% reduction in the volume of cerebral edema on fluid-attenuated inversion recovery–magnetic resonance imaging (FLAIR-MRI) after treatment (overall response rate, 46.6%; 95% CI, 33.3 to 60.1%). Twenty-five (43.1%) patients demonstrated a clinical improvement based on the Late Effects Normal Tissues–Subjective, Objective, Management, Analytic (LENT/SOMA) scale, and 36 (62.1%) experienced cognitive improvement based on the Montreal Cognitive Assessment (MoCA) scores. In a mouse model of RIBI, thalidomide restored the blood-brain barrier and cerebral perfusion, which were attributed to the functional rescue of pericytes secondary to elevation of platelet-derived growth factor receptor β (PDGFRβ) expression by thalidomide. Our data thus demonstrate the therapeutic potential of thalidomide for the treatment of radiation-induced cerebral vasculature impairment.

AbstractObjectiveUse of tacrolimus in mild to moderate myasthenia gravis (MG) is generally limited to glucocorticoid‐refractory cases; the advantage of mono‐tacrolimus over mono‐glucocorticoids is unknown.MethodsWe included mild to moderate MG patients treated with mono‐tacrolimus (mono‐TAC) or mono‐glucocorticoids (mono‐GC). The correlation between the immunotherapy options and the treatment efficacy and side effects were examined in 1:1 propensity‐score matching. The main outcome was time to minimal manifestations status or better (MMS or better). Secondary outcomes include time to relapse, the mean changes in Myasthenia Gravis‐specific Activities of Daily Living (MG‐ADL) scores and the rate of adverse events.ResultsBaseline characteristics showed no difference between matched groups (49 matched pairs). There were no differences in median time to MMS or better between the mono‐TAC group and mono‐GC group (5.1 vs. 2.8 months: unadjusted hazard ratio [HR], 0.73; 95% CI, 0.46–1.16; p = 0.180), as well as in median time to relapse (data unavailable for the mono‐TAC group since 44 of 49 [89.8%] participants remained in MMS or better; 39.7 months in mono‐GC group: unadjusted HR, 0.67; 95% CI, 0.23–1.97; p = 0.464). Changes in MG‐ADL scores between the two groups were similar (mean differences, 0.3; 95% CI, −0.4 to 1.0; p = 0.462). The rate of adverse events was lower in the mono‐TAC group compared to the mono‐GC group (24.5% vs. 55.1%, p = 0.002).InterpretationMono‐tacrolimus performs superior tolerability with non‐inferior efficacy compared to mono‐glucocorticoids in mild to moderate myasthenia gravis patients who refuse or have a contraindication to glucocorticoids.