122 research outputs found
Different RsbR paralogs in Bacillus subtilis affect cell viability when exposed to environmental stress
Stress is a universal phenomenon experienced by all living organisms. Bacteria have to react to stress quickly in order to survive in their environment. Environmental stress can be caused by a variety of factors, including acid, alcohol, salt, and heat. We are studying the model bacterium Bacillus subtilis, because its stress response resembles that of human pathogens such as Listeria. B. subtilis senses stress using a stressosome, a complex of 80 proteins that includes four variant RsbR protein paralogs, each of which produce a distinct stress response pattern to an identical stressor. We know that these four RsbR proteins work together to aid in survival in the presence of environmental stress in wild-type cells (WT), which contain all four RsbR proteins; however, we do not know how each RsbR protein affects cell fitness. To test how each individual RsbR protein affects survival, we performed a competition assay pairing strains containing individual RsbR variants against each other to determine if one protein aided in cell survival more than the other. To do this, we engineered strains of B. subtilis cells to only contain one of the four RsbR proteins. This allowed us to compete the RsbR proteins against one another on an individual basis. Our preliminary results indicate that the wild-type strain substantially outcompeted the other strains in every competition assay performed under acid stress except when competed against RC. These results show that cells containing only RC or all four RsbR proteins have a higher fitness in acid stress than cells containing only RA, RB, or RD.Lew Wentz FoundationMicrobiolog
Single-state Transcarotid Artery Revascularization Experience: Outcomes and Impact on Carotid Procedural and Operative Volumes
Objectives: Transcarotid artery revascularization (TCAR) is an emerging novel approach to carotid intervention, adopted and well-suited for high-risk patients. Our objective was to assess the outcomes of TCAR and determine its impact on the volume of carotid endarterectomy (CEA) and non-TCAR carotid artery stenting (CAS) in a single-state experience.
Methods: A large statewide quality consortium registry was queried. The indications and outcomes of TCAR compared with CEA and non-TCAR CAS from January 2018 to October 2019 were reviewed. Non-TCAR CAS included transfemoral, transbrachial stenting and transcarotid stenting without the flow reversal technique. We also assessed the impact of TCAR on the trend of CEA and non-TCAR CAS performed, analyzing data from 2012 to 2019. Outcome comparisons were performed using the χ 2 and Mann-Whitney U tests, depending on the distribution of the outcomes.
Results: A total of 438 TCARs were performed by 39 physicians in 16 hospitals; 60% of the patients were asymptomatic and 40% symptomatic. The TCAR indication was physiologic high risk for 369 patients (84%) and restenosis for 69 patients (16%), with most occurring after prior CEA (94%). Of the non-TCAR CAS cases, 94% were performed via transfemoral access. The patients undergoing non-TCAR CAS had the highest 30-day mortality ( P \u3c .001) and the highest incidence of 30-day new neurologic deficits ( P = .008) compared with the patients undergoing CEA and TCAR. CEA had the lowest myocardial infarction rate ( P = .015; Table). The number of TCAR procedures performed and the number of physicians and hospitals performing them increased during the 2-year period. Since the introduction of TCAR, no significant frequency decrease has occurred in the number of non-TCAR CAS or CEA cases by hospitals or physicians (Fig). However, a significant negative trend was found in the number of CEAs performed by physicians since 2012 ( P \u3c .001; Fig).
Conclusions: TCAR is a safe method of carotid revascularization and is becoming an increasingly used method. TCAR has not affected the CEA hospital or physician volume since its introduction. CEA volumes and physician usage are declining, which could have future credentialing implications. In the present single-state experience, TCAR compared favorably with CEA and non-TCAR CAS might be less appealing because of its higher neurologic event rate
The Grizzly, September 15, 2016
Board Chair Marcon Resigns Amid Controversy • Meet the Interim Board Chair • Black Girl Dangerous Comes to Speak at Ursinus • Student Work Hits the Stage • A Creative Approach to Raising Awareness • Opinions: Choose the America You Wish to be a Part of ; Students\u27 Guide to Weekends at Reimert • Field Hockey Off to a Hot Start, Looking for Redemption • You Bend \u27Em, We Mend \u27Em: The Life of an Athletic Trainerhttps://digitalcommons.ursinus.edu/grizzlynews/1648/thumbnail.jp
The Spinster Homolog, Two of Hearts, Is Required for Sphingosine 1-Phosphate Signaling in Zebrafish
SummaryThe bioactive lipid sphingosine 1-phosphate (S1P) and its G protein-coupled receptors play critical roles in cardiovascular, immunological, and neural development and function [1–6]. Despite its importance, many questions remain about S1P signaling, including how S1P, which is synthesized intracellularly, is released from cells. Mutations in the zebrafish gene encoding the S1P receptor Miles Apart (Mil)/S1P2 disrupt the formation of the primitive heart tube [5]. We find that mutations of another zebrafish locus, two of hearts (toh), cause phenotypes that are morphologically indistinguishable from those seen in mil/s1p2 mutants. Positional cloning of toh reveals that it encodes a member of the Spinster-like family of putative transmembrane transporters. The biological functions of these proteins are poorly understood, although phenotypes of the Drosophila spinster and zebrafish not really started mutants suggest that these proteins may play a role in lipid trafficking [7, 8]. Through gain- and loss-of-function analyses, we show that toh is required for signaling by S1P2. Further evidence indicates that Toh is involved in the trafficking or cellular release of S1P
Investigating the impact of the molecular charge-exchange rate on detached SOLPS-ITER simulations
Plasma-molecular interactions generate molecular ions which react with the
plasma and contribute to detachment through molecular activated recombination
(MAR), reducing the ion target flux, and molecular activated dissociation
(MAD), both of which create excited atoms. Hydrogenic emission from these atoms
have been detected experimentally in detached TCV, JET and MAST-U deuterium
plasmas. The TCV findings, however, were in disagreement with SOLPS-ITER
simulations for deuterium indicating a molecular ion density () that was
insufficient to lead to significant hydrogenic emission, which was attributed
to underestimates of the molecular charge exchange rate () for deuterium (obtained by rescaling the hydrogen rates by their
isotope mass).
In this work, we have performed new SOLPS-ITER simulations with the default
rate setup and a modified rate setup where ion isotope mass rescaling was
disabled. This increased the content by . By disabling
ion isotope mass rescaling: 1) the total ion sinks are more than doubled due to
the inclusion of MAR; 2) the additional MAR causes the ion target flux to
roll-over during detachment; 3) the total emission in the divertor
increases during deep detachment by roughly a factor four; 4) the neutral atom
density in the divertor is doubled due to MAD, leading to a 50\% increase in
neutral pressure; 5) total hydrogenic power loss is increased by up to 60\% due
to MAD. These differences result in an improved agreement between the
experiment and the simulations in terms of spectroscopic measurements, ion
source/sink inferences and the occurrence of an ion target flux roll-over
The Grizzly, September 22, 2016
UCEMS Halts Service Due to Policy Dispute • Tall Trees Music Fest: Local Musicians Play for Charity • U-Imagine\u27s New Marketing Competition Offers Ursinus Clubs Free Advertising • Fear From Around the World • Gender Inequalities in Tech and Science • When Art and the Environment Collide • Opinions: What Mia McKenzie\u27s Visit Meant to Me; New Era: Food Trucks Become Ursinus Tradition • Goal! Men\u27s and Women\u27s Soccer Prepared for the 2016 Season • Brother Bears on the Fieldhttps://digitalcommons.ursinus.edu/grizzlynews/1649/thumbnail.jp
The Grizzly, September 28, 2016
Campus Safety Takes Safety Initiatives • Poet Comes to UC • ESL Program Promotes Community Between Students and Staff • New Club Aims to Get Money Out of Politics • Shakespeare in the Summer of Love • Family Day Branches Out • Opinions: Let\u27s (Finally) Talk About Sex Addiction; Frank Ocean\u27s Blonde was Worth Waiting For • Ursinus Men\u27s and Women\u27s Cross Country Team Off to a Hot Start • Rare Breed: The Two-Sport Athletehttps://digitalcommons.ursinus.edu/grizzlynews/1650/thumbnail.jp
The Grizzly, October 13, 2016
Annual Safety Report Released • Ma Tones Brings Music to Collegeville • Come to Me Campaign Raises Awareness • International Perspective: French TA Excited to Learn What it\u27s Really Like to Live in the U.S. • Students Unite for Worker Justice • Partnership in Politics • Opinions: New Face of Change: A Defense of Millennials; Students Need to Understand Consent • UC Athletes Give Back to Their Community • Rafter Tackles Milestonehttps://digitalcommons.ursinus.edu/grizzlynews/1652/thumbnail.jp
- …