Directing Differentiation of Pluripotent Stem Cells Toward Retinal Pigment Epithelium Lineage

Development of efficient and reproducible conditions for directed differentiation of pluripotent stem cells into specific cell types is important not only to understand early human development but also to enable more practical applications, such as in vitro disease modeling, drug discovery, and cell therapies. The differentiation of stem cells to retinal pigment epithelium (RPE) in particular holds promise as a source of cells for therapeutic replacement in age-related macular degeneration. Here we show development of an efficient method for deriving homogeneous RPE populations in a period of 45 days using an adherent, monolayer system and defined xeno-free media and matrices. The method utilizes sequential inhibition and activation of the Activin and bone morphogenetic protein signaling pathways and can be applied to both human embryonic stem cells and induced pluripotent stem cells as the starting population. In addition, we use whole genome transcript analysis to characterize cells at different stages of differentiation that provides further understanding of the developmental dynamics and fate specification of RPE. We show that with the described method, RPE develop through stages consistent with their formation during embryonic development. This characterization- together with the absence of steps involving embryoid bodies, three-dimensional culture, or manual dissections, which are common features of other protocols-makes this process very attractive for use in research as well as for clinical applications. SIGNIFICANCE: This report describes a novel method of directed differentiation to generate retinal pigment epithelium (RPE) cells from pluripotent stem cells. The employed method is based on adherent monolayer culture using xeno-free conditions and manipulation of the Activin and bone morphogenetic protein signaling pathway using small molecules and recombinant proteins. Whole genome microarray analysis was performed to characterize the differentiation process and understand the developmental path of RPE generation in vitro. This method can be applied for generation of RPE for research as well as for clinical applications

Using ordinal logistic regression to evaluate the performance of laser-Doppler predictions of burn-healing time

Background Laser-Doppler imaging (LDI) of cutaneous blood flow is beginning to be used by burn surgeons to predict the healing time of burn wounds; predicted healing time is used to determine wound treatment as either dressings or surgery. In this paper, we do a statistical analysis of the performance of the technique. Methods We used data from a study carried out by five burn centers: LDI was done once between days 2 to 5 post burn, and healing was assessed at both 14 days and 21 days post burn. Random-effects ordinal logistic regression and other models such as the continuation ratio model were used to model healing-time as a function of the LDI data, and of demographic and wound history variables. Statistical methods were also used to study the false-color palette, which enables the laser-Doppler imager to be used by clinicians as a decision-support tool. Results Overall performance is that diagnoses are over 90% correct. Related questions addressed were what was the best blood flow summary statistic and whether, given the blood flow measurements, demographic and observational variables had any additional predictive power (age, sex, race, % total body surface area burned (%TBSA), site and cause of burn, day of LDI scan, burn center). It was found that mean laser-Doppler flux over a wound area was the best statistic, and that, given the same mean flux, women recover slightly more slowly than men. Further, the likely degradation in predictive performance on moving to a patient group with larger %TBSA than those in the data sample was studied, and shown to be small. Conclusion Modeling healing time is a complex statistical problem, with random effects due to multiple burn areas per individual, and censoring caused by patients missing hospital visits and undergoing surgery. This analysis applies state-of-the art statistical methods such as the bootstrap and permutation tests to a medical problem of topical interest. New medical findings are that age and %TBSA are not important predictors of healing time when the LDI results are known, whereas gender does influence recovery time, even when blood flow is controlled for. The conclusion regarding the palette is that an optimum three-color palette can be chosen 'automatically', but the optimum choice of a 5-color palette cannot be made solely by optimizing the percentage of correct diagnoses

Light-ion production in the interaction of 175 MeV quasi-mono-energetic neutrons with iron and with bismuth

Nuclear data for neutron-induced reactions in the intermediate energy range of 20 to 200 MeV are of great importance for the development of nuclear reaction codes since little data exist in that range. Also several different applications benefit from such data, notably accelerator-driven incineration of nuclear waste. The Medley setup was used for a series of measurements of p, d, t, $^3$He and $\alpha$-particle production by 175 MeV quasi-mono-energetic neutrons on various target nuclei. The measurements were performed at the The Svedberg Laboratory in Uppsala, Sweden. Eight detector telescopes placed at angles between 20$^\circ$ and 160$^\circ$ were used. Medley uses the $\Delta E$-$\Delta E$-$E$ technique to discriminate among the particle types and is able to measure double-differential cross sections over a wide range of particle energies. This paper briefly describes the experimental setup, summarizes the data analysis and reports on recent changes in the previously reported preliminary data set on bismuth. Experimental data are compared with INCL4.5-Abla07, MCNP6 using CEM03.03, TALYS and PHITS model calculations as well as with nuclear data evaluations. The models agree fairly well overall but in some cases systematic differences are found.Comment: 16 pages, 19 figures; submitted to Phys. Rev.

Quench performance of Fermilab high gradient quadrupole short models for the LHC Interaction Regions

Fermilab and LBNL are in the midst of superconducting magnet R&D program to test and optimize the design of quadrupoles to be used in the LHC Interaction Region inner triplets. The magnets are required to deliver a 215 T/m gradient across a 70 mm aperture. Five quadrupole short models have been fabricated and four of them have been tested. This paper describes the last model design details and reports the results of the magnet quench performance study. (5 refs)

Field quality of quadrupole R&D models for the LHC IR

Superconducting quadrupole magnets operating in superfluid helium at 1.9 K, with 70 mm bore and nominal field gradient of 205 T/m at collision optics, are being developed by the US LHC Accelerator Project for the Interaction Regions of the Large Hadron Collider (LHC). A magnet model program to validate and optimize the design is underway. This paper reports results of field quality measurements of four model magnets. (3 refs)

An intraoperative telemedicine program to improve perioperative quality measures: The ACTFAST-3 randomized clinical trial

IMPORTANCE: Telemedicine for clinical decision support has been adopted in many health care settings, but its utility in improving intraoperative care has not been assessed. OBJECTIVE: To pilot the implementation of a real-time intraoperative telemedicine decision support program and evaluate whether it reduces postoperative hypothermia and hyperglycemia as well as other quality of care measures. DESIGN, SETTING, AND PARTICIPANTS: This single-center pilot randomized clinical trial (Anesthesiology Control Tower-Feedback Alerts to Supplement Treatments [ACTFAST-3]) was conducted from April 3, 2017, to June 30, 2019, at a large academic medical center in the US. A total of 26 254 adult surgical patients were randomized to receive either usual intraoperative care (control group; n = 12 980) or usual care augmented by telemedicine decision support (intervention group; n = 13 274). Data were initially analyzed from April 22 to May 19, 2021, with updates in November 2022 and February 2023. INTERVENTION: Patients received either usual care (medical direction from the anesthesia care team) or intraoperative anesthesia care monitored and augmented by decision support from the Anesthesiology Control Tower (ACT), a real-time, live telemedicine intervention. The ACT incorporated remote monitoring of operating rooms by a team of anesthesia clinicians with customized analysis software. The ACT reviewed alerts and electronic health record data to inform recommendations to operating room clinicians. MAIN OUTCOMES AND MEASURES: The primary outcomes were avoidance of postoperative hypothermia (defined as the proportion of patients with a final recorded intraoperative core temperature \u3e36 °C) and hyperglycemia (defined as the proportion of patients with diabetes who had a blood glucose level ≤180 mg/dL on arrival to the postanesthesia recovery area). Secondary outcomes included intraoperative hypotension, temperature monitoring, timely antibiotic redosing, intraoperative glucose evaluation and management, neuromuscular blockade documentation, ventilator management, and volatile anesthetic overuse. RESULTS: Among 26 254 participants, 13 393 (51.0%) were female and 20 169 (76.8%) were White, with a median (IQR) age of 60 (47-69) years. There was no treatment effect on avoidance of hyperglycemia (7445 of 8676 patients [85.8%] in the intervention group vs 7559 of 8815 [85.8%] in the control group; rate ratio [RR], 1.00; 95% CI, 0.99-1.01) or hypothermia (7602 of 11 447 patients [66.4%] in the intervention group vs 7783 of 11 672 [66.7.%] in the control group; RR, 1.00; 95% CI, 0.97-1.02). Intraoperative glucose measurement was more common among patients with diabetes in the intervention group (RR, 1.07; 95% CI, 1.01-1.15), but other secondary outcomes were not significantly different. CONCLUSIONS AND RELEVANCE: In this randomized clinical trial, anesthesia care quality measures did not differ between groups, with high confidence in the findings. These results suggest that the intervention did not affect the targeted care practices. Further streamlining of clinical decision support and workflows may help the intraoperative telemedicine program achieve improvement in targeted clinical measures. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02830126

Test results of Fermilab-built quadrupoles for the LHC interaction regions

As part of the US LHC Accelerator Project, Fermilab is nearing the completion of the Q2 optical elements for the LHC interaction region final focus. Each Q2 element (LQXB) consists of two identical high gradient quadrupoles (MQXB) with a dipole orbit corrector (MCBX). This paper summarizes the test results for the LQXB/MQXB program including quench performance, magnetic measurements and alignment, and gives the status of production and delivery of the LQXB magnets to the LHC

A controlled trial of mental illness related stigma training for medical students

Article deposited according to agreement with BMC, December 6, 2010.YesFunding provided by the Open Access Authors Fund