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Evolutionary arms races can arise at the contact surfaces between host and viral proteins, producing dynamic spaces in which genetic variants are continually pursued.  However, the sampling of genetic variation must be balanced with the need to maintain protein function. A striking case is given by protein kinase R (PKR), a member of the mammalian innate immune system. PKR detects viral replication within the host cell and halts protein synthesis to prevent viral replication by phosphorylating eIF2α, a component of the translation initiation machinery. PKR is targeted by many viral antagonists, including poxvirus pseudosubstrate antagonists that mimic the natural substrate, eIF2α, and inhibit PKR activity. Remarkably, PKR has several rapidly evolving residues at this interface, suggesting it is engaging in an evolutionary arms race, despite the surface's critical role in phosphorylating eIF2α. To systematically explore the evolutionary opportunities available at this dynamic interface, we generated and characterized a library of 426 SNP-accessible nonsynonymous variants of human PKR for their ability to escape inhibition by the model pseudosubstrate inhibitor K3, encoded by the vaccinia virus gene K3L . We identified key sites in the PKR kinase domain that harbor K3-resistant variants, as well as critical sites where variation leads to loss of function. We find K3-resistant variants are readily available throughout the interface and are enriched at sites under positive selection. Moreover, variants beneficial against K3 were also beneficial against an enhanced variant of K3, indicating resilience to viral adaptation. Overall, we find that the eIF2α-binding surface of PKR is highly malleable, potentiating its evolutionary ability to combat viral inhibition., Competing Interests: MC, SS, MS No competing interests declared

Understanding the genetic causes of trait variation is a primary goal of genetic research. One way that individuals can vary genetically is through variable pangenomic genes: genes that are only present in some individuals in a population. The presence or absence of entire genes could have large effects on trait variation. However, variable pangenomic genes can be missed in standard genotyping workflows, owing to reliance on aligning short-read sequencing to reference genomes. A popular method for studying the genetic basis of trait variation is linkage mapping, which identifies quantitative trait loci (QTLs), regions of the genome that harbor causative genetic variants. Large-scale linkage mapping in the budding yeast Saccharomyces cerevisiae has found thousands of QTLs affecting myriad yeast phenotypes. To enable the resolution of QTLs caused by variable pangenomic genes, we used long-read sequencing to generate highly complete de novo genome assemblies of 16 diverse yeast isolates. With these assemblies, we resolved QTLs for growth on maltose, sucrose, raffinose, and oxidative stress to specific genes that are absent from the reference genome but present in the broader yeast population at appreciable frequency. Copies of genes also duplicate onto chromosomes where they are absent in the reference genome, and we found that these copies generate additional QTLs whose resolution requires pangenome characterization. Our findings show the need for highly complete genome assemblies to identify the genetic basis of trait variation., (© 2023 Weller et al.; Published by Cold Spring Harbor Laboratory Press.)

IgG antibodies play a role in malaria immunity, but whether and how IgM protects from malaria and the biology of Plasmodium falciparum (Pf)-specific IgM B cells is unclear. In a Mali cohort spanning infants to adults, we conducted longitudinal analyses of Pf- and influenza-specific B cells. We found that Pf-specific memory B cells (MBCs) are disproportionally IgM+ and only gradually shift to IgG+ with age, in contrast to influenza-specific MBCs that are predominantly IgG+ from infancy to adulthood. B cell receptor analysis showed Pf-specific IgM MBCs are somatically hypermutated at levels comparable to influenza-specific IgG B cells. During acute malaria, Pf-specific IgM B cells expand and upregulate activation/costimulatory markers. Finally, plasma IgM was comparable to IgG in inhibiting Pf growth and enhancing phagocytosis of Pf by monocytes in vitro. Thus, somatically hypermutated Pf-specific IgM MBCs dominate in children, expand and activate during malaria, and produce IgM that inhibits Pf through neutralization and opsonic phagocytosis., Competing Interests: Disclosures: The authors declare no competing interests exist., (© 2021 Hopp et al.)

Detection and monitoring of patients with pulmonary hypertension, defined as a mean blood pressure in the main pulmonary artery above 25 mmHg, requires a combination of imaging and hemodynamic measurements. This study demonstrates how to combine imaging data from microcomputed tomography images with hemodynamic pressure and flow waveforms from control and hypertensive mice. Specific attention is devoted to developing a tool that processes computed tomography images, generating subject-specific arterial networks in which one-dimensional fluid dynamics modeling is used to predict blood pressure and flow. Each arterial network is modeled as a directed graph representing vessels along the principal pathway to ensure perfusion of all lobes. The one-dimensional model couples these networks with structured tree boundary conditions representing the small arteries and arterioles. Fluid dynamics equations are solved in this network and compared to measurements of pressure in the main pulmonary artery. Analysis of microcomputed tomography images reveals that the branching ratio is the same in the control and hypertensive animals, but that the vessel length-to-radius ratio is significantly lower in the hypertensive animals. Fluid dynamics predictions show that in addition to changed network geometry, vessel stiffness is higher in the hypertensive animal models than in the control models.

Understanding how broadly neutralizing antibodies (bnAbs) to influenza hemagglutinin (HA) naturally develop in humans is critical to the design of universal influenza vaccines. Several classes of bnAbs directed to the conserved HA stem were found in multiple individuals, including one encoded by heavy-chain variable domain V H 6-1. We describe two genetically similar V H 6-1 bnAb clonotypes from the same individual that exhibit different developmental paths toward broad neutralization activity. One clonotype evolved from a germline precursor recognizing influenza group 1 subtypes to gain breadth to group 2 subtypes. The other clonotype recognized group 2 subtypes and developed binding to group 1 subtypes through somatic hypermutation. Crystal structures reveal that the specificity differences are primarily mediated by complementarity-determining region H3 (CDR H3). Thus, while V H 6-1 provides a framework for development of HA stem-directed bnAbs, sequence differences in CDR H3 junctional regions during VDJ recombination can alter reactivity and evolutionary pathways toward increased breadth., Competing Interests: Declaration of Interests The authors declare no competing interests., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Vaccine-induced memory B cell responses to evolving viruses like influenza A involve activation of pre-existing immunity and generation of new responses. To define the contribution of these two types of responses, we analyzed the response to H7N9 vaccination in H7N9-naive adults. We performed comprehensive comparisons at the single-cell level of the kinetics, Ig repertoire, and activation phenotype of established pre-existing memory B cells recognizing conserved epitopes and the newly generated memory B cells directed toward H7 strain-specific epitopes. The recall response to conserved epitopes on H7 HA involved a transient expansion of memory B cells with little observed adaptation. However, the B cell response to newly encountered epitopes was phenotypically distinct and generated a sustained memory population that evolved and affinity matured months after vaccination. These findings establish clear differences between newly generated and pre-existing memory B cells, highlighting the challenges in achieving long-lasting, broad protection against an ever-evolving virus., (Published by Elsevier Inc.)

Antigenic drift and shift of influenza strains underscore the need for broadly protective influenza vaccines. One strategy is to design immunogens that elicit B cell responses against conserved epitopes on the hemagglutinin (HA) stem. To better understand the elicitation of HA stem-targeted B cells to group 1 and group 2 influenza subtypes, we compared the memory B cell response to group 2 H7N9 and group 1 H5N1 vaccines in humans. Upon H7N9 vaccination, almost half of the HA stem-specific response recognized the group 1 and group 2 subtypes, whereas the response to H5N1 was largely group 1-specific. Immunoglobulin repertoire analysis of HA-specific B cells indicated that the H7N9 and H5N1 vaccines induced genetically similar cross-group HA stem-binding B cells, albeit at a much higher frequency upon H7N9 vaccination. These data suggest that a group 2-based stem immunogen could prove more effective than a group 1 immunogen at eliciting broad cross-group protection in humans., (Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Junctional hemorrhage, bleeding that occurs at the junction of the trunk and its appendages, is the most common preventable cause of death from compressible hemorrhage on the battlefield. As of January 2014, four types of junctional tourniquets have been developed and cleared by the U.S. Food and Drug Administration (FDA). Successful use of the Abdominal Aortic Tourniquet (AAT™) and Combat Ready Clamp (CRoC™) has already been reported. We report here the first known prehospital use of the SAM® Junctional Tourniquet (SJT) for a battlefield casualty with inguinal junctional hemorrhage., (2014.)

Cystic fibrosis (CF) is a chronic disease requiring patients to have frequent specialty healthcare visits to delay progression of lung disease, prevent and treat failure to thrive and initiate early interventions to prevent acute illness and complications. The CF Foundation recommends that patients have visits with the CF care team at least every 3 months. During participation in the CF Foundation Learning and Leadership Collaborative IV, the CF team at Arkansas Children's Hospital initiated quality improvement work with the aim to increase the percentage of patients attending clinic four or more times a year from 35% in 2004 and 56% in 2005 (CF Foundation Registry data) to 90% or greater. We redesigned our scheduling system, rescheduled missed patient appointments in a timely fashion and created a process to monitor attendance. This quality improvement work led to a sustained increase in the percentage of patients attending clinic visits four or more times a year reaching our goal of 90% in 2012. Improvements were also noted in the number of patients with body mass index/weight-for-length centile of 25 or greater, which could be related to more frequent clinic attendance.

A remarkable ability to tolerate temperatures as high as 52 degrees C for Mezium affine Boieldieu and 56 degrees C for Gibbium aequinoctiale Boieldieu (Coleoptera: Anobiidae) was discovered as part of a water balance study that was conducted to determine whether desiccation-resistance (xerophilic water balance classification) is linked to survival at high temperature. Characteristics of the heat shock response were an intermediate, reversible level of injury, appearing as though dead; greater recovery from heat shock by G. aequinoctiale (57%) than M. affine (30%) that supplemented higher temperature survival by G. aequinoctiale; and lack of protection generated by conditioning at sublethal temperature. Heatinduced mortality is attributed to an abrupt, accelerated water loss at 50 degrees C for M. affine and 54 degrees C for G. aequinoctiale, not to the species (M. affine) that loses water the slowest and has the lower activation energy, E(a) as a measure of cuticular boundary effectiveness. These temperatures where water loss increases sharply are not critical transition temperatures because Arrhenius analysis causes them to be erased (uninterrupted Boltzmann function) and E(a) fails to change when cuticular lipid from these beetles is removed. Our conclusion is that the temperature thresholds for survival and accelerated water loss closely match, and the key survival element in hot and dry environments contributing to wide distribution of G. aequinoctiale and M. affine derives from rising temperature prompting entry into quiescence and a resistance in cuticular lipid fluidity.

The use of behavioral restraint in psychiatric inpatients can have physically and emotionally damaging effects. However, staff may view the use of restraint as a routine and acceptable means of maintaining safety. The goal of this project was to reduce the use of restraint in a public psychiatric inpatient service that serves an economically disadvantaged urban population. Six interventions that primarily involved changing staff behavior were made to reduce the use of restraint. These included better identification of restraint-prone patients, a stress/anger management group for patients, staff training on crisis intervention, development of a crisis response team, daily review of all restraints, and an incentive system for the staff. The rate of restraint use (number of restraints/1000 patient-days) during the 3 years before the interventions was compared with the rate during the 2 years after the interventions. There was a significant decrease in the rate of restraint use after the restraint reduction initiatives were implemented. The reduction was not accompanied by a sustained increase in incidents of assault, suicidal behavior, or self-injury.

Objectives: To identify foodservice directors' use of performance measures and to determine their current practices of, and attitudes and beliefs about, benchmarking., Design: A survey was conducted using a researcher-developed questionnaire that had been validated in a pilot-test. The questionnaire was mailed to 600 randomly selected foodservice directors; 247 (41%) responses were analyzed., Subjects/setting: Subjects were foodservice directors in the United States from 4 categories of foodservice operations: college/university, correctional, health care, and school., Statistical Analyses: Results were analyzed using descriptive statistics and chi 2 tests to investigate associations between variables of interest., Results: The most common performance measures used by foodservice directors were food cost percentage, cost per unit or area of service, and meals per labor hour. Internal benchmarking had been used by 71% of the respondents, external benchmarking by 60%, and functional/generic by 25%. Seventy-seven percent of the respondents thought benchmarking had some or great importance in their jobs. Category of foodservice operation was associated with type of benchmarking partner and was related to certain performance measures. Sixty-one percent of respondents reported needing knowledge and skills about benchmarking., Applications/conclusions: Foodservice directors, regardless of category of foodservice operation, perceive benchmarking as a useful management tool to improve processes, products and services. Foodservice directors can use benchmarking to compare their financial performance with that of other organizations and learn how to improve their facility by examining best-practice processes of successful organizations.

"This paper explores the responses of fertility and nuptiality to fluctuations in real wages and mortality that can be inferred from annual series of English historical data over the period 1542 to 1800. The paper begins with a review of the time series properties of the data and summarizes the long-term equilibrium relationships identified in previous work.... An investigation is made of the impact of shocks to real wages and mortality on demographic variables as measured by generalized impulse responses and persistence profiles.", (excerpt)

In recent years, wrist actigraphy has been scrutinized as a possible supplement to or even replacement for other methods traditionally used to assess the sleep of clinical patients and research subjects. While showing promise for some applications, its accuracy in measuring the nocturnal sleep of insomniacs remains in question. A reexamination of the relevant data indicates that with respect to estimating the total sleep time of insomnia patients, use of the actigraph does not yield significantly lower error than daily sleep logs and predicts only about a third of the variance. However, the actigraph does show some potential for assessing the night-to-night variability of a given individual's sleep, suggesting that it may be most useful for assessing longitudinal changes within a treatment program or experimental protocol.

This study examined the relationships among anxiety, nocturnal sleep, and daytime restedness over a 1-week period, using the Spielberger State-Trait Anxiety Inventory and daily sleep logs. Among both insomniacs and controls, between-subjects correlations showed a significant negative relationship between state anxiety at bedtime and restedness during the day. Neither variable was related to nocturnal sleep variables. Within-subject correlations showed similar relationships between state anxiety and restedness the following day. For insomniacs, but not for normal sleepers, bedtime state anxiety was also significantly correlated with sleep latency. The authors hypothesize that anxiety, not sleep deprivation, may be responsible for the insomniac's complaint of daytime fatigue.

"Modern time series methods are applied to the analysis of annual demographic data for England, 1541-1800. Evidence is found of non-stationarity in the series and of co-integration among the series. Building on economic models of historical demography, optimal inferential procedures are implemented to estimate the structural parameters of long-term equilibria among the variables. Evidence is found for a small, but significant, Malthusian 'preventive check' as well as interactions between fertility, mortality and nuptiality that are consistent with the predictions often made in demographic studies. Tentative experiments to detect the influence of environmental factors fail to reveal any significant impact on the estimates obtained.", (excerpt)

This study examined (a) the efficacy, and (b) predictors of outcome of a brief (one to four sessions) behavioral treatment program for chronic insomnia. A total of 103 insomnia patients were treated, and outcome was assessed by a follow-up questionnaire. Outcome variables, including both nocturnal sleep parameters and measures of daytime functioning, showed significant improvement subsequent to treatment. Pretreatment sleep hygiene practices were significantly correlated with daytime fatigue and sleep latency outcome factors. Pre- and post-treatment complaints of daytime fatigue were associated with somatic complaints in general, but not with nocturnal sleep variables. Explanatory hypotheses are discussed.

Since its founding in 1917, The American Dietetic Association has been concerned with the development and improvement of educational programs for the professional dietitian. This article traces the evolution of professional dietetic educational programs from its beginning in the early cooking schools in the nineteenth century through the development of educational standards, the requirement for training beyond the bachelor's degree, and the establishment of academic requirements. The continued importance of educating the professional dietitian is evidenced by the inclusion of academic requirements as a prerequisite to membership in the Association.

Research was undertaken to develop, administer, and evaluate two forms of a criterion-referenced test instrument for measuring the competency status of students graduating from undergraduate programs in general dietetics. Involved in the evaluation of the final forms were 186 students graduating from fourteen college or university programs. Results are reported on the content validity, concurrent validity, reliability, and summary and individual test-item statistics. It is concluded that the test forms need further refinement and development and that the use of criterion-referenced evaluation tools to measure academic competency of students graduating in dietetics is needed.

Attempts to restore PRL receptors (PRL-R) in liver membranes of hypophysectomized rats with injections of PRL have so far been only partly successful. In the present study, bovine PRL (bPRL) was mixed with polyvinylpyrrolidone (PVP) in order to sustain PRL blood levels with a single injection a day. PRL-R were measured by displacement of the binding of [125I]ovine PRL (lactoperoxidase oxidation) to a 5000 x g particulate fraction of liver by unlabeled ovine PRL. The number of binding sites was calculated by Scatchard analysis and expressed as femtomoles per mg protein. PRL-R were 85 +/- 12 fmol/mg in normal intact female rats. Seven days posthypophysectomy, PRL-R were undetectable. Daily injections of bPRL with PVP for 10 days fully restored PRL-R (117 +/- 32 fmol/mg). No significant change in PRL-R was noted when bPRL was injected with bovine GH (bGH; 120 +/- 23 fmol/mg), bovine LH (bLH; 84 +/- 14 fmol/mg), bGH plus bLH (90 +/- 12 fmol/mg), or estrogens (79 +/- 12 fmol/mg). Daily injections of bGH or bLH, alone or in combination, or estrogens with PVP failed to restore PRL-R. These results demonstrate a direct role of PRL in stimulating the production of its own receptors when a sustained blood level of the hormone is achieved.

Test instruments for evaluating The American Dietetic Association's Minimum Academic Competencies were developed and tested for four major instructional areas--food, nutrition, nutrition in disease, and management--relevant to professional sciences for general dietetics. The study consisted of four steps: Development of objectives or test criteria; determination of mastery performance standards; test instrument development; and test administration and evaluation. This paper describes procedures used in developing and testing two forms of a criterion-referenced test instrument, which was then administered to determine academic competency of students in dietetics. Salient findings of the test results and evaluation are reported.