👤 Lewis Ari Eisen

Sex differences in the association between vascular factors and cognitive outcomes remain unclear. We aimed to investigate the associations of blood pressure metrics (hypertension, systolic blood pressure [SBP), pulse pressure, ankle and brachial pressures, and ankle to brachial pressure index [ABI]) with the risk of cognitive decline and dementia. We conducted a population-based longitudinal analysis using data from the Atherosclerosis Risk in Communities (ARIC) study (begun in 1987-1989) in the United States. We analyzed a total of 12,268 participants aged 45-64 years who had validated exposure measurements, cognitive function tests (first administrated 1990-1992), and followed up for incidence of dementia through December 2019. Cognitive function was assessed using the Digit Symbol Substitution Test, the Delayed Word Recall Test, and the Word Fluency Test. Dementia cases were identified through a standardized clinical evaluation process, mostly adjudicated by expert reviewers. We performed sex-stratified analyses to examine the associations of blood pressure metrics and APOE ε4 allele with the risk of cognitive decline and dementia. Over a median follow-up of 26.4 years, 2698 participants developed dementia. Women aged 55-64 had a significantly higher incidence of dementia than men aged 55-64 (14.8 vs. 11.8 per 1000 person-years; p < These findings highlight notable sex differences in the association between vascular factors and cognitive decline and dementia risk. Women appear more vulnerable to both genetic and vascular risk factors, emphasizing the need for sex-specific approaches in research, prevention, and intervention strategies for cognitive impairment. NIH. Show less

Chorea-acanthocytosis (ChAc) and McLeod syndrome are diseases with shared clinical manifestations caused by mutations in VPS13A and XK, respectively. Key features of these conditions are the degeneration of caudate neurons and the presence of abnormally shaped erythrocytes. XK belongs to a family of plasma membrane (PM) lipid scramblases whose action results in exposure of PtdSer at the cell surface. VPS13A is an endoplasmic reticulum (ER)-anchored lipid transfer protein with a putative role in the transport of lipids at contacts of the ER with other membranes. Recently VPS13A and XK were reported to interact by still unknown mechanisms. So far, however, there is no evidence for a colocalization of the two proteins at contacts of the ER with the PM, where XK resides, as VPS13A was shown to be localized at contacts between the ER and either mitochondria or lipid droplets. Here we show that VPS13A can also localize at ER-PM contacts via the binding of its PH domain to a cytosolic loop of XK, that such interaction is regulated by an intramolecular interaction within XK, and that both VPS13A and XK are highly expressed in the caudate neurons. Binding of the PH domain of VPS13A to XK is competitive with its binding to intracellular membranes that mediate other tethering functions of VPS13A. Our findings support a model according to which VPS13A-dependent lipid transfer between the ER and the PM is coupled to lipid scrambling within the PM. They raise the possibility that defective cell surface exposure of PtdSer may be responsible for neurodegeneration. Show less

Communication and teamwork are essential during inpatient emergencies such as cardiac arrest and rapid response (RR) codes. We investigated whether wearing numbered jerseys affect directed commands, teamwork, and performance during simulated codes. Eight teams of 6 residents participated in 64 simulations. Four teams were randomized to the experimental group wearing numbered jerseys, and four to the control group wearing work attire. The experimental group used more directed commands (49% vs. 31%, p < .001) and had higher teamwork score (25 vs. 18, p < .001) compared with control group. There was no difference in time to initiation of chest compression, bag-valve-mask ventilation, and correct medications. Time to defibrillation was longer in the experimental group (190 vs. 140 seconds, p = .035). Using numbered jerseys during simulations was associated with increased use of directed commands and better teamwork. Time to performance of clinical actions was similar except for longer time to defibrillation in the jersey group. Show less

Situation awareness has been defined as the perception of the elements in the environment within volumes of time and space, the comprehension of their meaning, and the projection of their status in the near future. Intensivists often make time-sensitive critical decisions, and loss of situation awareness can lead to errors. It has been shown that simulation-based training is superior to lecture-based training for some critical scenarios. Because the methods of training to improve situation awareness have not been well studied in the medical field, we compared the impact of simulation vs. lecture training using the Situation Awareness Global Assessment Technique (SAGAT) score. To identify an effective method for teaching situation awareness. We randomly assigned 17 critical care fellows to simulation vs. lecture training. Training consisted of eight cases on airway management, including topics such as elevated intracranial pressure, difficult airway, arrhythmia, and shock. During the testing scenario, at random times between 4 and 6 minutes into the simulation, the scenario was frozen, and the screens were blanked. Respondents then completed the 28 questions on the SAGAT scale. Sample items were categorized as Perception, Projection, and Comprehension of the situation. Results were analyzed using SPSS Version 21. Eight fellows from the simulation group and nine from the lecture group underwent simulation testing. Sixty-four SAGAT scores were recorded for the simulation group and 48 scores were recorded for the lecture group. The mean simulation vs. lecture group SAGAT score was 64.3 ± 10.1 (SD) vs. 59.7 ± 10.8 (SD) (P = 0.02). There was also a difference in the median Perception ability between the simulation vs. lecture groups (61.1 vs. 55.5, P = 0.01). There was no difference in the median Projection and Comprehension scores between the two groups (50.0 vs. 50.0, P = 0.92, and 83.3 vs. 83.3, P = 0.27). We found a significant, albeit modest, difference between simulation training and lecture training on the total SAGAT score of situation awareness mainly because of the improvement in perception ability. Simulation may be a superior method of teaching situation awareness. Show less

We sought to create a comprehensive catalog of yeast genes whose transcript levels vary periodically within the cell cycle. To this end, we used DNA microarrays and samples from yeast cultures synchronized by three independent methods: alpha factor arrest, elutriation, and arrest of a cdc15 temperature-sensitive mutant. Using periodicity and correlation algorithms, we identified 800 genes that meet an objective minimum criterion for cell cycle regulation. In separate experiments, designed to examine the effects of inducing either the G1 cyclin Cln3p or the B-type cyclin Clb2p, we found that the mRNA levels of more than half of these 800 genes respond to one or both of these cyclins. Furthermore, we analyzed our set of cell cycle-regulated genes for known and new promoter elements and show that several known elements (or variations thereof) contain information predictive of cell cycle regulation. A full description and complete data sets are available at http://cellcycle-www.stanford.edu Show less