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Abstract: We report measurements of the transverse diffusion of electrons in P-10 gas (90% Ar, 10% CH4) in a laboratory-scale time projection chamber (TPC) utilizing a novel pixelated signal capture and digitization technique known as Q-Pix. The Q-Pix method incorporates a precision switched integrating transimpedance amplifier whose output is compared to a threshold voltage. Upon reaching the threshold, a comparator sends a 'reset' signal, initiating a discharge of the integrating capacitor. The time difference between successive resets is inversely proportional to the average current at the pixel in that time interval, and the number of resets is directly proportional to the total collected charge. We developed a 16-channel Q-Pix prototype fabricated from commercial off-the-shelf components and coupled them to 16 concentric annular anode electrodes to measure the spatial extent of the electron swarm that reaches the anode after drifting through the uniform field of the TPC. The swarm is produced at a gold photocathode using pulsed UV light. The measured transverse diffusion agrees with simulations in PyBoltz across a range of operating pressures (200–1500 Torr). These results demonstrate that a Q-Pix readout can successfully reconstruct the ionization topology in a TPC.

A 59-year-old man who under surveillance for abdominal aortic aneurysm and peripheral artery disease, was investigated with a CT Angiogram aorta. The CT scan showed an abdominal aortic aneurysm reaching 6.2cm with significant thrombus burden, occluded coeliac artery, occluded left iliac artery, calcified stenosis of the right renal artery and features of chronic renal infarct in the right upper pole. Technetium-99m dimercaptosuccinic acid (Tc-99m DMSA) renal scan was done to document the extent of the infarction and for differential function of the kidneys.

Pediatric malignancies frequently harbor chromosomal translocations that induce expression of fusion oncoproteins. The EWSR1-FLI1 fusion oncoprotein acts as a neomorphic transcription factor and is the dominant genetic driver of Ewing's sarcoma. Interrogation of the mechanisms by which EWSR1-FLI1 drives tumorigenesis has been limited by a lack of model systems to precisely and selectively control its expression in patient-derived cell lines and xenografts. Here, we report the generation of a panel of patient-derived EWS cell lines in which inducible protein degrons were engineered into the endogenous EWSR1-FLI1 locus. These alleles enabled rapid and efficient depletion of EWSR1-FLI1. Complete suppression of EWSR1-FLI1 induced a reversible cell cycle arrest at the G 1 -S checkpoint, and we identified a core set of transcripts downstream of EWSR1-FLI1 across multiple cell lines and degron systems. Additionally, depletion of EWSR1-FLI1 potently suppressed tumor growth in xenograft models validating efforts to directly target EWSR1-FLI1 in Ewing's sarcoma.

A subset of people living with HIV (PLWH) can produce broadly neutralizing antibodies (bNAbs) against HIV, but the lymph node (LN) dynamics that promote the generation of these antibodies are poorly understood. Here, we explored LN-associated histological, immunological, and virological mechanisms of bNAb generation in a cohort of anti-retroviral therapy (ART)-naïve PLWH. We found that participants who produce bNAbs, termed neutralizers, have a superior LN-associated B cell follicle architecture compared with PLWH who do not. The latter was associated with a significantly higher in situ prevalence of Bcl-6 hi follicular helper CD4 T cells (TFH), expressing a molecular program that favors their differentiation and stemness, and significantly reduced IL-10 follicular suppressor CD4 T cells. Furthermore, our data reveal possible molecular targets mediating TFH- B cell interactions in neutralizers. Together, we identify cellular and molecular mechanisms that contribute to the development of bNAbs in PLWH., Competing Interests: Disclosure of Conflicts of Interest The authors declare no competing conflicts of interest.

Despite antiretroviral therapy (ART), people living with human immunodeficiency virus (HIV) (PLWH) continue to experience chronic inflammation and immune dysfunction, which drives the persistence of latent HIV and prevalence of clinical comorbidities. Elucidating the mechanisms that lead to suboptimal immunity is necessary for developing therapeutics that improve the quality of life of PLWH. Although previous studies have found associations between gut dysbiosis and immune dysfunction, the cellular/molecular cascades implicated in the manifestation of aberrant immune responses downstream of microbial perturbations in PLWH are incompletely understood. Recent literature has highlighted that two abundant metabolite families, short-chain fatty acids (SCFAs) and bile acids (BAs), play a crucial role in shaping immunity. These metabolites can be produced and/or modified by bacterial species that make up the gut microbiota and may serve as the causal link between changes to the gut microbiome, chronic inflammation, and immune dysfunction in PLWH. In this review, we discuss our current understanding of the role of the microbiome on HIV acquisition and latent HIV persistence despite ART. Further, we describe cellular/molecular cascades downstream of SCFAs and BAs that drive innate or adaptive immune responses responsible for promoting latent HIV persistence in PLWH. This knowledge can be used to advance HIV cure efforts.

Purpose: To investigate late vitreoretinal complications and visual outcomes in patients with regressed retinopathy of prematurity (ROP) with or without prior treatment., Design: International, multicenter, noncomparative retrospective case series., Participants: We analyzed 264 eyes of 238 patients from 13 centers worldwide who developed vitreoretinal complications (retinal detachment [RD], vitreous hemorrhage [VH], or retinal break) ≥ 2 years after resolution of acute ROP., Methods: Each participant was assigned to 1 of 3 groups (the RD, VH, and retinal break groups) according to their primary diagnosis. The average age at presentation, visual acuities, refractive error, axial length, gestational age, birth weight, acute ROP classification, prior treatments for acute ROP, postoperative visual acuity (VA), and concomitant eye conditions in the 3 groups were documented and compared., Main Outcome Measures: Clinical features and visual outcomes of late vitreoretinal complications in patients with regressed ROP., Results: A total of 264 eyes of 238 patients were included. The prior acute ROP status was comparable among the 3 groups, except that the VH group had a higher proportion of patients with type 1 ROP (P = 0.03) and prior treatment (P < 0.001) than the other groups. The average age at presentation was earlier in the RD (20.3 ± 15.5 years) and VH (21.4 ± 18.9 years) groups than in the retinal break group (31.9 ± 18.2 years; P < 0.001). The retinal break group had the best presenting best-corrected VA, followed by the RD and VH groups (P < 0.001). Surgical intervention improved VA in both the RD and VH groups (both P < 0.05). The overall trend of VA was the most favorable in the retinal break group, followed by that in the VH and RD groups. Cicatricial changes in the fellow retina were observed in > 90% of patients with unilateral involvement., Conclusions: Infants with acute ROP remain at a high risk of vision-threatening complications throughout childhood and adulthood. Continual follow-up of patients with ROP is important. When severe complications, such as RD or VH, are detected, timely surgical intervention is necessary to ensure favorable visual outcomes in these patients., (Copyright © 2022 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Early Th 17 responses are necessary to provide protection against Mycobacterium tuberculosis (Mtb). Mtb impedes Th 17 polarization by restricting CD40 co-stimulatory pathway on dendritic cells (DCs). We previously demonstrated that engaging CD40 on DCs increased Th 17 responses. However, the molecular mechanisms that contributed to Th 17 polarization were unknown. Here, we identify the Notch ligand DLL4 as necessary for Th 17 polarization and demonstrate that Mtb limits DLL4 on DCs to prevent optimal Th 17 responses. Although Mtb infection induced only low levels of DLL4, engaging CD40 on DCs increased DLL4 expression. Antibody blockade of DLL4 on DCs reduced Th 17 polarization in vitro and in vivo . In addition, we show that the Mtb Hip1 protease attenuates DLL4 expression on lung DCs by impeding CD40 signaling. Overall, our results demonstrate that Mtb impedes CD40-dependent DLL4 expression to restrict Th 17 responses and identify the CD40-DLL4 pathways as targets for developing new Th 17 -inducing vaccines and adjuvants for tuberculosis., Competing Interests: The authors declare no competing interests., (© 2022 The Author(s).)

Tuberculosis (TB) remains one of the leading causes of death worldwide due to a single infectious disease agent. BCG, the only licensed vaccine against TB, offers limited protection against pulmonary disease in children and adults. TB vaccine research has recently been reinvigorated by new data suggesting alternative administration of BCG induces protection and a subunit/adjuvant vaccine that provides close to 50% protection. These results demonstrate the need for generating adjuvants in order to develop the next generation of TB vaccines. However, development of TB-targeted adjuvants is lacking. To help meet this need, NIAID convened a workshop in 2020 titled "Advancing Vaccine Adjuvants for Mycobacterium tuberculosis Therapeutics". In this review, we present the four areas identified in the workshop as necessary for advancing TB adjuvants: 1) correlates of protective immunity, 2) targeting specific immune cells, 3) immune evasion mechanisms, and 4) animal models. We will discuss each of these four areas in detail and summarize what is known and what we can advance on in order to help develop more efficacious TB vaccines., Competing Interests: Author RNM was employed by company Columbus Technologies & Services Inc. JE and SM are employees of and own shares in Inimmune Corporation. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Enriquez, Izzo, Miller, Stewart, Mahon, Frank, Evans, Rengarajan and Triccas.)

Purpose: To evaluate features and outcomes of eyes with retinal vasculitis and intraocular inflammation (IOI) after intravitreal injection (IVI) of brolucizumab 6 mg/0.05 ml for treatment of neovascular age-related macular degeneration., Design: Retrospective case series., Participants: Fifteen eyes from 12 patients identified from 10 United States centers., Methods: Review of patient demographics, ophthalmologic examination results, and retinal imaging findings., Main Outcome Measures: Baseline and follow-up visual acuity (VA), prior anti-vascular endothelial growth factor (VEGF) injections, clinical presentation, retinal findings, fluorescein angiography results, and treatment strategies., Results: The number of previous anti-VEGF IVIs ranged between 2 and 80 in the affected eye before switching to brolucizumab. Retinal vasculitis and IOI were diagnosed at a mean of 30 days after brolucizumab IVI. Mean VA before brolucizumab IVI was 0.426 logarithm of the minimum angle of resolution (logMAR; Snellen equivalent, 20/53) and VA at diagnosis of retinal vasculitis was 0.981 logMAR (Snellen equivalent, 20/191; range, 20/25-20/1600; P = 0.008). All affected eyes showed IOI with variable combinations of focal or elongated segmental sheathing and discontinuity of small and large retinal arteries, sclerotic arteries, regions of vascular nonperfusion, cotton-wool spots, Kyrieleis plaques, irregular venous caliber with dilated and sclerotic segments, perivenular hemorrhages, and foci of phlebitis. Fluorescein angiography revealed delayed retinal arterial filling, retinal vascular nonperfusion, and variable dye leakage from affected vessels and the optic nerve. Systemic evaluation for embolic causes was unrevealing in 2 patients, and 3 patients showed negative laboratory assessment for uveitis. Treatment consisted of various combinations of corticosteroids (systemic, intravitreal, and topical), and 2 eyes underwent vitrectomy without improvement in vision. After a mean follow-up of 25 days, mean VA was 0.833 logMAR (Snellen equivalent, 20/136), which was reduced compared with baseline (P = 0.033)., Conclusions: Retinal vasculitis and IOI after brolucizumab IVI are characterized by variable occlusion of large or small retinal arteries, or both, and perivenular abnormalities. It may span from peripheral vasculitis to occlusion of large retinal arteries around the optic nerve or macula with severe vision loss. A high index of suspicion is required because vitreous cells may obscure visualization of retinal details., (Copyright © 2020 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Disorders of sex development (DSDs) are congenital anomalies that affect sexual differentiation of genitourinary organs and secondary sex characters. A common cause of female genital virilization is congenital adrenal hyperplasia (CAH), in which excess androgen production during development of 46XX females can result in vaginal atresia, masculinization of the urethra, a single urogenital sinus, and clitoral hypertrophy or ambiguous external genitalia. Development of the vagina depends on sexual differentiation of the urogenital sinus ridge, an epithelial thickening that forms where the sex ducts attach to the anterior urethra. In females, the sinus ridge descends posteriorly to allow the vaginal opening to form in the vulva, whereas in males and in females with CAH, androgens inhibit descent of the sinus ridge. The mechanisms that regulate development of the female urethra and vagina are largely unknown. Here we show that the timing and duration of, and the cell population targeted by, androgen signaling determine the position of vaginal attachment to the urethra. Manipulations of androgen signaling in utero reveal a temporal window of development when sinus ridge fate is determined. Cell type-specific genetic deletions of androgen receptor (Ar) identify a subpopulation of mesenchymal cells that regulate sinus ridge morphogenesis. These results reveal a common mechanism that coordinates development of the vagina and feminization of the urethra, which may account for development of a single urogenital sinus in females exposed to excessive androgen during a critical period of prenatal development., Competing Interests: The authors declare no conflict of interest.

Sjögren's syndrome (SS) is an autoimmune disease characterized by lymphocytic infiltration of the salivary and lacrimal glands. The aim of the study was to characterize and compare the presence of diverse cytokines and regulatory T and B cells in lip minor salivary gland (MSG) biopsies from patients with primary Sjögren's syndrome (pSS), secondary SS (sSS), and patients with connective tissue disease (CTD) without (w/o) SS. We included samples of MSG from 15 pSS, 24 sSS (six scleroderma, nine rheumatoid arthritis and nine lupus patients) and 15 patients with CTD w/o SS. Tissues were examined by an indirect immunoperoxidase technique (goat polyclonal anti-human IL-19, goat polyclonal anti-human IL-22 or mouse monoclonal anti-human IL-24). To determine the subpopulation of CD4(+)/IL-17A(+)-, CD4(+)/IL-4(+)-, CD4(+)/IFN-ɣ(+)-expressing T cells, CD25(+)/Foxp3(+) Treg cells and CD20(+)/IL-10(+)-producing B cell subset, a double-staining procedure was performed. We estimated the mean percentage of positively staining cells in two fields per sample. CD4(+)/IFN-ɣ(+), CD4(+)/IL-4(+) and IL-22(+) cell percentages were elevated in both SS varieties; however, the cells were more prevalent in pSS. Patients with pSS had a high number of CD4(+)/IL-17A(+) and IL-19(+) T cells and a lower percentage of IL-24(+) cells (P < 0.05). The Treg and IL-10-producing B cells were increased in pSS (P < 0.05). Concluding, in our patients, a pro-inflammatory and regulatory balance coexists in SS, being both responses more intense in pSS. The explanation of these differences may be related to disease activity, disease duration and treatment., (© 2014 John Wiley & Sons Ltd.)

Background: The exposure of phosphatidylserine occurs during platelet (PLT) activation and during in vitro storage. Phosphatidylserine exposure also occurs during apoptosis after the release of mitochondrial cytochrome c. We have examined the role of cytochrome c release, mitochondrial membrane potential (ΔΨm), and cyclophilin D (CypD) in phosphatidylserine exposure due to activation and storage., Study Design and Methods: The exposure of phosphatidylserine and the loss of ΔΨm were determined in a flow cytometer using fluorescein isothiocyanate-lactadherin and JC-1, a lipophilic cationic reporter dye. The role of CypD was determined with cyclosporin A and CypD-deficient murine PLTs. Cytochrome c-induced caspase-3 and Rho-associated kinase I (ROCK1) activation were determined by immunoblotting and using their inhibitors., Results: Collagen- and thrombin-induced exposure of phosphatidylserine was accompanied by a decrease in ΔΨm. Cyclosporin A inhibited the phosphatidylserine exposure and the loss of ΔΨm. CypD(-/-) mice had decreased loss of ΔΨm and impaired phosphatidylserine exposure. Collagen and thrombin did not induce the release of cytochrome c nor the activation of caspase-3 and ROCK1. In contrast, in PLTs stored for more than 5 days, the phosphatidylserine exposure was associated with cytochrome c-induced caspase-3 and ROCK1 activation. ABT737, a BH3 mimetic that induces mitochondrial pathway of apoptosis, induced cytochrome c release and activation of caspase-3 and ROCK1 and phosphatidylserine exposure independent of CypD., Conclusion: These results show that in stored PLTs cytochrome c release and the subsequent activation of caspase-3 and ROCK1 mediate phosphatidylserine exposure and it is distinct from activation-induced phosphatidylserine exposure., (© 2010 American Association of Blood Banks.)