Highly cooperative chimeric super-SOX induces naive pluripotency across species

Our understanding of pluripotency remains limited: iPSC generation has only been established for a few model species, pluripotent stem cell lines exhibit inconsistent developmental potential, and germline transmission has only been demonstrated for mice and rats. By swapping structural elements between Sox2 and Sox17, we built a chimeric super-SOX factor, Sox2-17, that enhanced iPSC generation in five tested species: mouse, human, cynomolgus monkey, cow, and pig. A swap of alanine to valine at the interface between Sox2 and Oct4 delivered a gain of function by stabilizing Sox2/Oct4 dimerization on DNA, enabling generation of high-quality OSKM iPSCs capable of supporting the development of healthy all-iPSC mice. Sox2/Oct4 dimerization emerged as the core driver of naive pluripotency with its levels diminished upon priming. Transient overexpression of the SK cocktail (Sox+Klf4) restored the dimerization and boosted the developmental potential of pluripotent stem cells across species, providing a universal method for naive reset in mammals.

Ctrl+Alt+Delete in the name of COVID-19:When a reset leads to misrecognition☆

When the COVID-19 pandemic struck the world in March 2020, it impacted all areas of society. Most conspicuous were the lockdowns that were quickly imposed in many countries along with other restrictions. These interventions into the everyday life of ordinary citizens were, perhaps not surprisingly, often met with resistance by citizens and businesses that felt their rights were being trampled on by governments. In this paper, we analyse reactions towards the far-reaching measures taken by the Danish government to contain the spread of the COVID-19 virus in the fur industry and thereby prevent the development of new mutations of the virus: to cull all minks and temporarily ban mink production in Denmark. We argue that by studying this case, valuable lessons can be learned regarding how a business community reacts when faced with a great reset. Taking the current climate crisis into consideration, it must be expected that emission-heavy industries, like agriculture, will be faced with calls to radically change their mode of production in the near future. In this sense, we propose to view the Danish mink case as an early example of what a great reset could look like, how it is perceived by those who experience it first-hand, and how feelings of resentment and resistance can develop following a logic of (mis)recognition.

Unusual response to His-synchronous ventricular stimulation during a supraventricular tachycardia: Atrial advancement with or without resetting?

The delivery of ventricular extra-stimulus when the His bundle is refractory is the most important maneuver in the diagnosis of an accessory pathway conduction.The "reset" indicates that the extra-stimulus has penetrated the circuit to alter the "subsequent cycle'. The advanced atrial activation time is expected to affect (reset or terminate) the tachycardia to the next cycle. However, some pitfalls should be kept in mind in the evaluation of the resetting response. This article is protected by copyright. All rights reserved.

Antegrade slow pathway mapping of typical atrioventricular nodal reentrant tachycardia based on direct slow pathway capture

BACKGROUND

Radiofrequency (RF) ablation of typical atrioventricular nodal reentrant tachycardia (tAVNRT) is performed without revealing out the location of antegrade slow pathway (ASp). In this study, we studied a new electrophysiological method of identifying the site of ASp.

METHODS

This study included 19 patients. Repeated series of very high-output single extrastimulations (VhoSESts) were delivered at the anatomical slow pathway region during tAVNRT. Tachycardia cycle length (TCL), coupling interval (CI), and return cycle (RC) were measured and the prematurity of VhoSESts [ΔPM (= TCL - CI)] and the prolongation of RCs [ΔPL (= RC - TCL)] were calculated. Pacing sites were classified into two categories: (i) ASp capture sites [DSPC(+) sites], where two different RCs were shown, and ASp non-capture sites [DSPC(-) sites], where only one RC was shown. RF ablation was performed at DSPC(+) sites and/or sites with catheter-induced mechanical trauma (CIMT) to ASp.

RESULTS

DSPC(+) sites were shown in 13 patients (68%). RF ablation was successful in all patients without any degree of atrioventricular block nor recurrence. Total number of RF applications was 1.8 ± 1.1. Minimal distance between successful ablation sites and DSPC(+)/CIMT sites and His bundle (HB) electrogram recording sites was 1.9 ± 0.8 mm and 19.8 ± 6.1 mm, respectively. ΔPL of more than 92.5 ms, ΔPL/TCL of more than 0.286, and ΔPL/ΔPM of more than 1.565 could identify ASp with sensitivity of 100%, 91.1%, and 88.9% and specificity of 92.9%, 97.0%, and 97.6%, respectively.

CONCLUSIONS

Sites with ASp capture and CIMT were close to successful ablation sites and could be useful indicators of tAVNRT ablation.

Slowed Progression of Age-Related Geographic Atrophy Following Subthreshold Laser

Purpose

To determine the effect of panmacular low-intensity/high-density subthreshold diode micropulse laser (SDM) on age-related geographic atrophy (ARGA) progression.

Methods

The retinal images of all eyes with ARGA in a previously reported database, consisting of all eyes with dry age-related macular degeneration (AMD) active in a vitreoretinal practice electronic medical record (EMR), were identified and analyzed to determine the velocity of radial linear ARGA progression during observation and after panmacular SDM.

Results

Sixty-seven eyes of 49 patients with ARGA, mean age of 86 years were identified as having follow-up both before and after initiation of SDM treatment. All were included in the study. These eyes were followed a mean 910 days (2.5 years) prior to SDM treatment and a mean 805 days (2.2 years) after. Measurement masked to treatment vs observation found the radius of ARGA lesions progressed 1 to 540 µm per year (mean 137µm, SD 107) prior to treatment (controls); and −44 to 303 µm per year (mean 73µm, SD 59) after initiation of periodic panmacular SDM laser. Thus, the velocity of radial linear progression decreased 47% per year following panmacular SDM (p<0.0001). There were no adverse treatment effects.

Conclusion

In cohort of eyes with high-risk dry AMD, panmacular SDM slowed linear radial ARGA progression velocity 47% per year (p<0.0001) without adverse treatment effects. Validated, these findings would constitute an important advance in the prevention of age-related visual loss and a benchmark for future therapies.

Subthreshold Diode Micropulse Laser (SDM) for Persistent Macular Thickening and Limited Visual Acuity After Epiretinal Membrane Peeling

Purpose

To examine the effect of low-intensity/high-density subthreshold diode micropulse laser (SDM) on visual acuity (VA) and macular thickness in eyes with limited visual recovery and persistent macular thickening after epiretinal membrane peeling.

Methods

A retrospective review of medical records identified all patients undergoing SDM after membrane peeling in a clinical vitreoretinal subspecialty practice. Exclusion criteria included other obfuscating ocular disease or loss to follow-up after SDM treatment.

Results

All 19 eyes of 18 patients identified were included for study. After membrane peeling, VA improved from an avg. Snellen 20/240 [logMAR 1.08] to 20/72 [0.56] (p=0.0004). Attributed to persistent macular thickening following membrane peeling, overall VAs then gradually declined to an avg. of 20/91 [0.66] by 4−109 months (avg. 41) post vitrectomy, at which point panmacular SDM was performed. An avg. 15 months post SDM, both VA (to avg. 20/68 [0.53]) and maximum macular thickness improved (p=0.007 and p=0.008, respectively). There were no adverse treatment effects.

Conclusion

Low-intensity/high-density subthreshold (sublethal) diode micropulse laser (SDM) may reduce macular thickening and improve visual in eyes with persistent macular thickening after membrane peeling even years after vitrectomy.

CikA, an Input Pathway Component, Senses the Oxidized Quinone Signal to Generate Phase Delays in the Cyanobacterial Circadian Clock

The circadian clock is a timekeeping system in most organisms that keeps track of the time of day. The rhythm generated by the circadian oscillator must be constantly synchronized with the environmental day/night cycle to make the timekeeping system truly advantageous. In the cyanobacterial circadian clock, quinone is a biological signaling molecule used for entraining and fine-tuning the oscillator, a process in which the external signals are transduced into biological metabolites that adjust the phase of the circadian oscillation. Among the clock proteins, the pseudo-receiver domain of KaiA and CikA can sense external cues by detecting the oxidation state of quinone, a metabolite that reflects the light/dark cycle, although the molecular mechanism is not fully understood. Here, we show the antagonistic phase shifts produced by the quinone sensing of KaiA and CikA. We introduced a new cyanobacterial circadian clock mixture that includes an input component in vitro. KaiA and CikA cause phase advances and delays, respectively, in this circadian clock mixture in response to the quinone signal. In the entrainment process, oxidized quinone modulates the functions of KaiA and CikA, which dominate alternatively at day and night in the cell. This in turn changes the phosphorylation state of KaiC-the central oscillator in cyanobacteria-ensuring full synchronization of the circadian clock. Moreover, we reemphasize the mechanistic input functionality of CikA, contrary to other reports that focus only on its output action.

A 28 nm Bulk-CMOS Analog Front-End for High-Rate ATLAS Muon Drift-Tube Detectors

This paper presents the design and experimental characterization of a 28 nm Complementary Metal Oxide Semiconductor (CMOS) Analog Front-End (AFE) for fast-tracking small-diameter Muon Drift-Tube (sMDT) detectors. The device exploits an innovative analog signal processing that allows a strong increase in the detection rate of events and significantly reduces the impact of fake/pile-up events, which often corrupt incident radiation energy events. The proposed device converts the input charge coming from incident radiations into voltage by a dedicated Charge-Sensitive Preamplifier (CSPreamp). Therefore, the fast-tracking concept relies on sampling the slope of the CSPreamp output voltage and using it for detecting both the incident event arrival instant and the amount of charge that has been effectively read out by MDT detectors. This avoids the long processing times intrinsically needed for baseline recovery transient, during which the detected signal can be severely corrupted by additional and unwanted extra-events, resulting in extra-charge (and thus in CSP output voltage extra-transient) during the signal roll-off. The proposed analog channel operates with a 5-100 fC input charge range and has a maximum dead-time of 200 ns (against the 545 ns of the state-of-the-art). It occupies 0.03 mm2 and consumes 1.9 mW from 1 V of supply voltage.

Repeated Reuse of Deoxyribozyme-Based Logic Gates

Deoxyribozymes (DNAzymes) have demonstrated a significant capacity for biocomputing and hold promise for information processing within advanced biological devices if several key capabilities are developed. One required capability is reuse-having DNAzyme logic gates be cyclically, and controllably, activated and deactivated. We designed an oligonucleotide-based system for DNAzyme reuse that could (1) remove previously bound inputs by addition of complementary oligonucleotides via toe-hold mediated binding and (2) diminish output signal through the addition of quencher-labeled oligonucleotides complementary to the fluorophore-bound substrate. Our system demonstrated, for the first time, the ability for DNAzymes to have their activity toggled, with activity returning to 90-125% of original activity. This toggling could be performed multiple times with control being exerted over when the toggling occurs, with three clear cycles observed before the variability in activity became too great. Our data also demonstrated that fluorescent output of the DNAzyme activity could be actively removed and regenerated. This reuse system can increase the efficiency of DNAzyme-based logic circuits by reducing the number of redundant oligonucleotides and is critical for future development of reusable biodevices controlled by logical operations.

Effects of pay resets following drug use on attendance and hours worked in a therapeutic workplace

This secondary data analysis examined effects of an abstinence contingency on participation in a therapeutic workplace. Participants exposed to a pay reset after drug use did not differ in overall attendance from participants who were not exposed to a pay reset after drug use; however, they initially worked less after a pay reset than participants who did not receive a pay reset, and their attendance increased as their pay increased. Overall participation was not influenced by the abstinence contingency, but transient decreases in attendance occurred.