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Purpose: Despite potential benefits of intravenous (i.v.) administration of acetaminophen (APAP), consistent outcome data are lacking. This, combined with the higher acquisition cost of the drug, has led to variation in i.v. APAP management strategies. This project evaluated the contemporary formulary status and restrictions of i.v. APAP in the perioperative setting. Methods: A survey focusing on i.v. APAP formulary restriction in the perioperative setting was developed by the Vizient Pharmacy Research Committee and distributed to Vizient Pharmacy Program participant listservs for Pharmacy Directors or Drug Information Pharmacists. The four survey domains included hospital characteristics, perioperative i.v. APAP formulary status and prescribing restrictions, perioperative i.v. APAP use, and perioperative i.v. APAP medication use evaluation (MUE) results. Responses were collected and summarized, and primary outcomes were evaluated using Fisher’s exact test. Results: A total of 1195 surveys were distributed with a response rate of 19%. Respondents were equally distributed between academic medical centers (AMC) and non-academic medical centers (non-AMC). Two cohorts were examined: those with i.v. APAP on formulary and those without. The non-AMCs showed a larger proportion of hospitals with the medication on formulary ( P = .041). Regarding formulary decision-making, the AMCs were more considerate of value. Several different practices were employed to limit or restrict i.v. APAP. Conclusion: A survey of directors of pharmacy and drug information specialists revealed that the majority of hospitals have i.v. APAP on formulary for perioperative use, but use is restricted. Differences in i.v. APAP formulary practices between AMCs and non-AMCs warrant further consideration.

Objective: Autonomy-support and quality feedback have been shown to significantly impact student learning. Unfortunately, quality feedback is often very time consuming. The goal of this study was to examine the autonomy-supportive potential from feedback provided via technology, specifically the ExamSoft Strength and Opportunities report. Methods: Students were divided into two groups: one received enhanced performance feedback via the ExamSoft Strength and Opportunities report, the other received traditional grade-only feedback in the form of grades and course averages, via ExamSoft. The Learning Self-Regulation Survey (SRQ-L) was administered to 139 third-year doctor of pharmacy students. The survey contained 14 statements asking students to rate their reasons (relative autonomy) for reviewing ExamSoft feedback, three items related to use of the ExamSoft technology, and five demographic items. Results: A statistical difference, t(52) = -2.07, p =0.043; d = .577, was reported between the two groups indicating enhanced feedback via ExamSoft had a moderate impact on students’ autonomy. Conclusions: Students who received enhanced ExamSoft feedback reported significantly higher relative autonomy index (RAI) for feedback review than students who did not receive the feedback. This suggests that the enhanced ExamSoft feedback was autonomy-supportive. Conflict of Interest: None Treatment of Human Subjects: IRB review/approval required and obtained Type: Original Research

Objective. To assess the impact of the COVID-19 pandemic on pharmacy residency application/interview processes, match rate, and factors influencing match rankings at a single college of pharmacy Methods. In spring of 2020 and 2021, an anonymous survey of fourth-year pharmacy school (P4) residency applicants at one college of pharmacy was administered. Survey responses were compared to explore trends in showcase participation, number/type/geographic dispersion of applications submitted, interview invitations, grade point average (GPA), research experience, and match rate. A thematic analysis evaluated common factors influencing match rankings. Results. Responses were collected from 75 of 99 (75.8% response rate) residency-seeking students in 2020 and 79 of 94 (84.0% response rate) in 2021. Students in 2021 reported applying to a higher median number of programs, with no significant differences in mean reported number of interview invitations or match rate. The virtual American Society of Health-System Pharmacists (ASHP) Midyear Showcase led to a median reported savings of $1000 with no significant impact on perceived value. Virtual interviews led to a median reported savings of $430. Thematic analysis revealed feel/culture, location, and learning experience options as the most prevalent deciding factors for match rankings in both years. Conclusion. The pandemic led to an increase in the number of residency applications per student and yielded a net cost savings. There were no differences in number of interviews offered, match rate, or in deciding factors influencing match rankings. As the pandemic evolves, schools should maintain a flexible and dynamic approach to support students.

Objective. To determine the ability of first-year Doctor of Pharmacy (PharmD) students to describe patient care activities performed by pharmacists and accurately associate those activities with the five core steps of the Pharmacists’ Patient Care Process (PPCP). Methods. First-year student pharmacists completed introductory practice experiences at ambulatory and institutional pharmacies. Students’ ability to describe activities that occurred in these settings and align them with the five core steps (collect, assess, plan, implement, and follow-up) of the PPCP were assessed. Results. The students were more adept in describing patient care activities and aligning them to the appropriate PPCP steps in an ambulatory pharmacy setting than in an institutional pharmacy setting. Students achieved higher scores when describing and aligning patient care activities associated with the collect and implement steps in an ambulatory pharmacy setting and for the assess step in an institutional pharmacy setting. Conclusion. As institutions strive to adopt the PPCP in all areas of the curriculum, this application serves as an example of successful PPCP integration early in the introductory experiential curriculum. Our results challenge faculty to provide early opportunities for students to apply the PPCP in a variety of practice settings, including settings focused on the medication distribution system.

Aims To assess the impact of a national programme in paediatric secondary care, to introduce ETAT protocols and train nursing staff to lead emergency management. Methods Within a wider strategy to reduce child mortality, the Sierra Leone Ministry of Health and Sanitation engaged WHO and RCPCH to introduce WHO Emergency Triage Assessment and Treatment (ETAT) protocols to all district hospitals. Two clinical mentors (one Sierra Leonean, one UK/international) were placed at each hospital for six months, and delivered a three-month teaching programme with a written and practical examination, as well as hands-on clinical mentorship. Upon passing the examination, nurses were awarded the right to assess, prescribe for, and treat emergency paediatric cases. The mentors collected treatment data each day on children admitted the previous day, and followed each child to record their discharge outcome. This programme monitoring data was analysed to identify compliance with clinical protocols, and to calculate mortality rates. The programme delivery period was split into seven four-week blocks, and compliance rates and mortality rates were calculated for each four-week period. Results We analysed monitoring data from three regional hospitals in the first phase of roll-out (table 1). The combined mortality rate across the three hospitals fell from 15% in the first four-week period, to 4% in the final period. This fall was accompanied by improvements in key areas of compliance with WHO ETAT standards. Conclusion This study suggests that implementation of ETAT protocols and delivery of improved quality of care and decreased mortality may be achievable with an effective and cost-efficient nurse-led model for emergency paediatric care in low-resource settings.

Despite recent advances in the understanding of ethanol's biological action, many of the molecular targets of ethanol and mechanisms behind ethanol's effect on behavior remain poorly understood. In an effort to identify novel genes, the products of which regulate behavioral responses to ethanol, we recently identified a mutation in the dtao gene that confers resistance to the locomotor stimulating effect of ethanol in Drosophila. dtao encodes a member of the Ste20 family of serine/threonine kinases implicated in MAP kinase signaling pathways. In this study, we report that conditional ablation of the mouse dtao homolog, Taok2, constitutively and specifically in the nervous system, results in strain-specific and overlapping alterations in ethanol-dependent behaviors. These data suggest a functional conservation of dtao and Taok2 in mediating ethanol's biological action and identify Taok2 as a putative candidate gene for ethanol use disorders in humans.

Few interprofessional education (IPE) models include patients and caregivers. To address this, we developed a novel model for teaching IP communication which included patients and caregivers as team members. We describe the model and our use of it in several health professions education curricula. We report preliminary data from learners regarding their experiences learning and utilizing the model as part of their IPE. Overall the model was positively viewed by students, although the perceived value of learning activities involving the model varied by discipline. Physical therapy, nursing, and pharmacy students valued the IPE model most, whereas medical students valued it the least. Received: 05/04/2015 Accepted: 08/21/2015 Published: 10/01/2015 © 2015 Conigliaro et al. This open access article is distributed under a Creative Commons Attribution License, which allows unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. H IP & Application and Student Perceptions of the PEEER© Model EDUCATIONAL STRATEGY 2(3):eP1079 | 2 Introduction In their report Crossing the Quality Chasm, the Institute of Medicine (Institute of Medicine Committee on Quality Health Care in America, 2001) identified the development of effective patient-centered teams as one of the re-design imperatives to achieve safe, effective, efficient, personalized, timely, and equitable care. The Core Competencies for Interprofessional Collaborative Practice sponsored by the Interprofessional Educational Collaborative (Interprofessional Education Collaborative Expert Panel, 2011) has refocused healthcare education’s attention on interprofessional education (IPE) and practice. As a result, many health professional training programs are developing curricula to improve the quantity and quality of interprofessional (IP) experiences (Aston et al., 2012; McNair, 2005), including training in IP communication and teamwork. Healthcare teams are complex, with multiple shared responsibilities in the provision of patient care, including creating team structure, ensuring professionalism, practicing flexibility, achieving conflict management, promoting trust and respect, and ensuring interand intra-team communication (Firth-Cozens, 2001; Hobgood et al., 2010). IP healthcare teams, which include members of different healthcare professions, must have shared goals focused on patients’ needs to provide effective health care. Accomplishing these goals may be particularly challenging when IP healthcare teams are composed of professionals with little prior experience working with team members from different disciplines (Barr, Hammick, Koppel & Reeves, 1999), as is often the case. Functioning effectively within an IP healthcare team may require individuals to develop skills beyond their traditional specialty training and education (Nembhard & Edmondson, 2006; Wanzer, Wojtaszczyk & Kelly, 2009). Effective communication among these IP team members is critical to the realization of team goals for safe, high-quality patient care. Our early experiences with IPE activities involving IP teams of students interacting with standardized patients revealed that students’ ability to form functional teams and communicate with each other was not intuitive. To address this and improve our educational process we identified existing models for communication among healthcare professionals (Apker, Propp, Zabava Ford, & Hofmeister, 2006; Boaro, Fancott, Baker, Velji & Andreoli, 2010; Ellingson, 2003; Wanzer et al., 2009), yet found little guidance for models of communication among IP healthcare teams which included patients as team members. Given the increasing emphasis on patient-centered care in many aspects of health care delivery, we believe that IPE should specifically address the inclusion of patients as part of the IP team. We therefore developed a schematic for IP team communication that stressed purposefully working together with each other as well as with the patient and their caregiver(s). In this context, “team” denotes the patient, caregiver, and all healthcare providers; caregiver is defined as anyone, family member or otherwise, who provides care and assistance, either personal or other care such as emotional or logistical support. Through literature review and iterative discussion, we identified five key skills essential for effective communication: 1) use of Plain Language understood by all team participants; 2) Engagement of all team members; 3) Empathy to convey an awareness of the experience of all team members; 4) Empowerment of each team member to actively participate; and 5) Respect for the experiences contributed by each team member. We named this the PEEER© model to allow easy recall of each skill and identified exemplar behaviors which demonstrate each skill (Conigliaro et al., 2013). The schematic representation of the PEEER© model (Figure 1, following page) includes all healthcare providers, patients, and caregivers and intentionally places all members as equal participants in the healthcare team communication process. It is built upon the foundational concept that all team members bring essential knowledge and skills to successful patient outcomes, stressing that effective team communication is both expressive and receptive. Of critical importance in the schematic is the non-hierarchical approach to valuing the contributions of each member of the team. Of additional importance is the flexibility of the model to be utilized with various pedagogical approaches. We present the PEEER© model’s use in health professions education, and report our preliminary results describing students experiences utilizing it.

The assembly of lipoprotein(a) (Lp(a)) involves an initial noncovalent interaction between apolipoprotein (apo) B100 and apo(a), followed by the formation of a disulfide bond between apoB100 cysteine 4326 and apo(a) cysteine 4057. The structural features of apoB100 that are required for its noncovalent interaction with apo(a) have not been fully defined. To analyze that initial interaction, we tested whether apo(a) could bind noncovalently to two apoB proteins that lack cysteine 4326: mouse apoB100 and human apoB100-C4326G. Our experiments demonstrated that both mouse apoB and the human apoB100-C4326G bind noncovalently to apo(a). We next sought to gain insights into the apoB amino acid sequences required for the interaction between apoB100 and apo(a). Previous studies of truncated human apoB proteins indicated that the carboxyl terminus of human apoB100 (amino acids 4330-4397) is important for Lp(a) assembly. To determine whether the carboxyl terminus of mouse apoB100 can interact with apo(a), transgenic mice were produced with a mutant human apoB gene construct in which human apoB100 amino acids 4279-4536 were replaced with the corresponding mouse apoB100 sequences and tyrosine 4326 was changed to a cysteine. The mutant apoB100 bound to apo(a) and formed bona fide disulfide-linked Lp(a), but Lp(a) assembly was less efficient than with wild-type human apoB100. The fact that Lp(a) assembly was less efficient with the mouse apoB sequences provides additional support for the notion that sequences in the carboxyl terminus of apoB100 are important for Lp(a) assembly.

Prior studies have established that the expression of the human apolipoprotein B (apoB) gene in the intestine is dependent on DNA sequences located a great distance from the structural gene. To identify the location of those sequences, we usedrecA-assisted restriction endonuclease (RARE) cleavage to truncate the 5′- or 3′-flanking sequences from a 145-kilobase (kb) bacterial artificial chromosome spanning the entire human apoB gene. Seven RARE cleavage– modified bacterial artificial chromosomes with different lengths of flanking sequences were used to generate transgenic mice. An analysis of those mice revealed that as little as 1.5 kb of 3′ sequences or 5 kb of 5′ sequences were sufficient to confer apoB expression in the liver. In contrast, apoB gene expression in the intestine required DNA sequences 54–62 kb 5′ to the structural gene. Those sequences retained their ability to direct apoB expression in the intestine when they were moved closer to the gene. These studies demonstrate that the intestinal expression of the apoB gene is dependent on DNA sequences located an extraordinary distance from the structural gene and that the RARE cleavage/transgenic expression strategy is a powerful approach for analyzing distant gene-regulatory sequences.

We show that the liver-specific expression of all four genes in the human apolipoprotein (apo) E/C-I/C-IV/C-II gene cluster in transgenic mice is determined by the coordinate action of two distinct hepatic control regions (HCR). These enhancers are positioned 15 kilobases (kb) (HCR.1) and 26 kb (HCR.2) downstream of the apoE gene. To investigate the action of each HCR, transgenic mice were generated with a 70-kb human genomic fragment that contained the complete apoE gene cluster or with this fragment modified by the specific deletion of HCR.1, HCR.2, or both HCR domains. Hepatic expression of all four apolipoprotein genes was observed in transgenic mice in which either HCR.1 or HCR.2 was deleted, but no transgene expression was found in the liver in the absence of both HCR domains. The overall patterns of transgene expression suggested that HCR.2 was the dominant element for apoC-IV and apoC-II expression and that HCR.1 was dominant for the apoE/C-I expression. No liver-specific transcriptional activity was identified for the proximal promoter of any gene in the cluster; all liver-specific activity was associated with HCR.1 and HCR.2. Thus, the HCRs of the apoE gene cluster constitute unique regulatory domains for determining the requirements for apolipoprotein gene expression in the liver.

The structural features of apolipoprotein (apo) B that are important for its covalent linkage to apo(a) to form lipoprotein(a) (Lp(a)) are incompletely understood. Although apoB100 cysteine 4326 is required for the disulfide linkage with apo(a), other structural features, aside from a single free cysteine residue, must be important for apoB’s initial interaction with apo(a) and for facilitating the formation of the disulfide bond. To determine if sequences carboxyl-terminal to cysteine 4326 affect the efficiency of Lp(a) formation, we used “pop-in, pop-out” gene targeting in a human apoB yeast artificial chromosome to introduce nonsense mutations into exon 29 of the apoB gene. The mutant yeast artificial chromosomes, which coded for the truncated versions of human apoB, apoB95, and apoB97, were then used to express these mutant forms of apoB in transgenic mice. As judged by in vitro assays of Lp(a) formation, apoB95 (4330 amino acids) formed a small amount of Lp(a) but did so slowly. In contrast, apoB97 (4397 amino acids) formed Lp(a) rapidly, although not quite as rapidly as the full-length apoB100 (4536 amino acids). These results were supported by an analysis of double-transgenic mice expressing both human apo(a) and either apoB95 or apoB97. In mice expressing both apoB95 and apo(a), there was only a trace amount of Lp(a) in the plasma, and most of the apo(a) was free, whereas in mice expressing both apoB97 and apo(a), virtually all of the apo(a) was bound to apoB97 in the form of Lp(a). These results show that sequences carboxyl-terminal to apoB95 (amino acids 4331–4536) are not absolutely required for Lp(a) formation, but this segment of the apoB molecule, particularly residues 4331–4397, is necessary for the efficient assembly of Lp(a).

Introduction This resource exposes learners to the challenges involved in effectively communicating within interprofessional teams and between teams, patients and caregivers, and provides learners with a template for overcoming these challenges and optimizing communication. The PEEER (Plain Language, Engagement, Empathy, Empowerment, Respect) model is a new model, grounded in communication and patient safety literature, to teach interprofessional (IP) communication to professionals who will be working in IP teams, and in IP teams with patients and caregivers. Methods The resource contains three sets of video clips demonstrating good and bad IP communication skills between health professionals and between health professionals and patients/caregivers. Accompanying these videos are worksheets for learners to critique the videos, and facilitator worksheets with prompts to help lead discussion about the good and bad communication skills demonstrated. Finally, the resource contains a learner postassessment which reflects how well they grasped the model components and concepts, and an evaluation of the process. Additional readings with extensive references are also provided. Results The PEEER model was incorporated into an existing interprofessional education (IPE) activity with health profession students in either their second year of the doctor of medicine (MD) program, third year of the doctor of pharmacy (PharmD) program, or fourth year of the bachelor of science in nursing (BSN) program. The evaluation of the IPE activity was sent to all student participants (119 MD, 124 PharmD, 78 BSN students) and completed surveys were received from 273 of 321 participants (91% MD student response rate, 94% PharmD response rate, 62% BSN response rate). Over 70% of the BSN and PharmD students, and 58% of MD, students agreed or strongly agreed that the PEEER model activity was a valuable education activity. Discussion The PEEER model can be tailored to complement any curriculum for all levels of learners in any of the health care disciplines. In addition, the PEEER model utilizes communication concepts familiar to most learners and educators, is grounded in the communications literature, and applies those concepts for use in a clinical setting where teams commonly function. The model is easily integrated into either simulated practice (such as in a course) or actual clinical experiences (either inpatient or outpatient situations) and can provide opportunities for the practice and improvement of interprofessional team skills.

The specificity of expression in the liver of the human apolipoprotein (apo) E/C-I gene locus is determined by a hepatic control region (HCR) that is located 15 kilobases downstream of the apoE gene. DNase I footprint studies of this sequence using nuclear extracts identified a region of the HCR that is enriched in nuclear protein-binding sites. Nuclease analysis of chromatin revealed liver-specific DNase I-hypersensitive sites that were associated with this region, and additional liver-specific nuclease-sensitive sites associated with the apoE gene were identified. The HCR domain has a limited binding affinity for the nuclear scaffold. The specific domain required for liver expression was tested by ligating subfragments of the HCR to the apoE gene and examining their activity in transgenic mice. A segment of 319 nucleotides that contained several potential regulatory sequences was required for full activity of liver-specific transcription with shorter segments yielding much lower levels of expression in the liver. All constructs that contained a fully active HCR were expressed in approximately a copy-dependent manner, suggesting that transgene expression was independent of integration position. Taken together, the properties of the HCR are consistent with its function as a locus control region for the liver-specific expression of the apoE gene.

Rat hepatoma McA-RH7777 cell lines transfected with full-length human apolipoprotein (apo) B constructs produce mostly human apoB48 and only small amounts of apoB100, as a result of mRNA editing at codon 2153 (C to U conversion at nucleotide 6666). To abolish the formation of apoB48 and increase the yield of apoB100 and other forms of apoB longer than apoB48, site-specific mutations were introduced at or near the site of apoB mRNA editing. Among four mutations examined, only that in which codon 2153 was converted from CAA (Gln) to CTA (Leu) effectively precluded the formation of apoB48. In this mutant, a stop codon would not be generated even if the C to U conversion occurred. The three other mutations were introduced to disrupt the proposed stem-loop structure encompassing the editing site. Changes made in the third positions of five codons on the 5' side of the edited base or of four codons 3' of the edited base failed to eliminate the production of a protein with the approximate size of apoB48. A construct in which codon 2153 was changed from CAA to GAT (Asp) also failed to eliminate the production of a protein the size of apoB48. Analysis of the region between nucleotides 6200 and 6900 of the cDNA did not detect any prevalent alternate editing sites. Immunoblot analysis using polyclonal antibodies raised against synthetic peptides of human apoB100 indicated that the carboxyl terminus of the apoB48-like proteins probably resides between amino acid residues 2068 and 2129 of apoB100. These results provide some insight into the mechanism of apoB mRNA editing and will facilitate further studies on apoB-containing lipoproteins.

Precise regulation of Wnt signaling is important in many contexts, as in development of the vertebrate forebrain, where excessive or ectopic Wnt signaling leads to severe brain defects. Mutation of the widely expressed oto gene causes loss of the anterior forebrain during mouse embryogenesis. Here we report that oto is the mouse ortholog of the gpi deacylase gene pgap1, and that the endoplasmic reticulum (ER)-resident Oto protein has a novel and deacylase-independent function during Wnt maturation. Oto increases the hydrophobicities of Wnt3a and Wnt1 by promoting the addition of glycophosphatidylinositol (gpi)-like anchors to these Wnts, which results in their retention in the ER. We also report that oto-deficient embryos exhibit prematurely robust Wnt activity in the Wnt1 domain of the early neural plate. We examine the effect of low oto expression on Wnt1 in vitro by knocking down endogenous oto expression in 293 and M14 melanoma cells using shRNA. Knockdown of oto results in increased Wnt1 secretion which is correlated with greatly enhanced canonical Wnt activity. These data indicate that oto deficiency increases Wnt signaling in vivo and in vitro. Finally, we address the mechanism of Oto-mediated Wnt retention under oto-abundant conditions, by cotransfecting Wnt1 with gpi-specific phospholipase D (GPI-PLD). The presence of GPI-PLD in the secretory pathway results in increased secretion of soluble Wnt1, suggesting that the gpi-like anchor lipids on Wnt1 mediate its retention in the ER. These data now provide a mechanistic framework for understanding the forebrain defects in oto mice, and support a role for Oto-mediated Wnt regulation during early brain development. Our work highlights a critical role for ER retention in regulating Wnt signaling in the mouse embryo, and gives insight into the notoriously inefficient secretion of Wnts.

We examined the relationship between the size of human apolipoprotein (apo) B and the formation and secretion of apoB-containing lipoprotein particles. Stable transformants of the rat hepatoma cell line McA-RH7777 harboring a variety of human apoB cDNA constructs were established, and these produced carboxyl-terminally truncated apoB proteins (apoB18, -B23, -B28, -B31, -B48, and -B53). Immunoblotting of apoB proteins secreted into the culture medium and fractionated by equilibrium density ultracentrifugation revealed that each of the truncated apoB species was secreted from the cells. The peak densities of the apoB-containing particles decreased as the length of the apoB proteins increased. Apolipoproteins B18 and B23 appeared at the bottom of the salt gradient (d = 1.23 g/ml), whereas particles containing apoB28, -B31, -B37, -B48, and -B53 exhibited progressive decreases in density. The density distribution of secreted apolipoproteins was not affected by the expression or secretion of these recombinant apoB species. As determined by nondenaturing gel electrophoresis, apoB28, -B31, -B37, -B48, and -B53 formed their own discrete particles, and there was a direct correlation between the size of the particles and the length of the apoB species. The efficiency and rate of secretion of these truncated forms of apoB were studied by measuring the decrease of immunoprecipitated 35S-labeled apoB proteins in the cells and their accumulation in the medium. Proteins corresponding to apoB28 or larger were rapidly and efficiently secreted, whereas apoB18 and apoB23 were secreted much more slowly. These data imply that the size of these truncated apoB forms governs the lipid content of the apoB-containing lipoproteins formed as well as the kinetics of secretion.

Dispersal can influence population dynamics, species distributions, and community assembly, but few studies have attempted to determine the factors that affect dispersal of insects in natural populations. Consequently, little is known about how proximate factors affect the dispersal behavior of individuals or populations, or how an organism's behavior may change in light of such factors. Adult predaceous diving beetles are active dispersers and are important predators in isolated aquatic habitats. We conducted interrelated studies to determine how several factors affected dispersal in two common pond-inhabiting species in southern Alberta, Canada: Graphoderus occidentalis and Rhantus sericans. Specifically, we (1) experimentally tested the effect of plant and beetle densities on dispersal probabilities in ponds; (2) surveyed ponds and determined the relationships among beetle densities and plant densities and water depth; and (3) conducted laboratory trials to determine how beetle behavior changed in response to variation in plant densities, conspecific densities, food, and water depth. Our field experiment determined that both species exhibited density dependence, with higher beetle densities leading to higher dispersal probabilities. Low plant density also appeared to increase beetle dispersal. Consistent with our experimental results, densities of R. sericans in ponds were significantly related to plant density and varied also with water depth; G. occidentalis densities did not vary with either factor. In the laboratory, behavior varied with plant density only for R. sericans, which swam at low density but were sedentary at high density. Both species responded to depth, with high beetle densities eliciting beetles to spend more time in deeper water. The presence of food caused opposite responses for G. occidentalis between experiments. Behavioral changes in response to patch-level heterogeneity likely influence dispersal in natural populations and are expected to be important for observed patterns of individuals in nature.

Lipoprotein(a) [Lp(a)] is a lipoprotein formed by the disulfide linkage of apolipoprotein (apo) B100 of a low density lipoprotein particle to apolipoprotein(a). Prior studies have suggested that one of the C-terminal Cys residues of apo-B100 is involved in the disulfide linkage of apo-B100 to apo(a). To identify the apo-B100 Cys residue involved in the formation of Lp(a), we constructed a yeast artificial chromosome (YAC) spanning the human apo-B gene and used gene-targeting techniques to change Cys-4326 to Gly. The mutated YAC DNA was used to generate transgenic mice expressing the mutant human apo-B100 (Cys4326Gly). Unlike the wild-type human apo-B100, the mutant human apo-B100 completely lacked the ability to bind to apo(a) and form Lp(a). This study demonstrates that apo-B100 Cys-4326 is required for the assembly of Lp(a) and shows that gene targeting in YACs, followed by the generation of transgenic mice, is a useful approach for analyzing the structure of large proteins coded for by large genes.

Apolipoprotein (apo-) B mRNA editing is the deamination of cytidine that creates a new termination codon and produces a truncated version of apo-B (apo-B48). The cytidine deaminase catalytic subunit [apo-B mRNA-editing enzyme catalytic polypeptide 1 (APOBEC-1)] of the multiprotein editing complex has been identified. We generated transgenic rabbits and mice expressing rabbit APOBEC-1 in their livers to determine whether hepatic expression would lower low density lipoprotein cholesterol concentrations. The apo-B mRNA from the livers of the transgenic mice and rabbit was extensively edited, and the transgenic animals had reduced concentrations of apo-B100 and low density lipoproteins compared with control animals. Unexpectedly, all of the transgenic mice and a transgenic rabbit had liver dysplasia, and many transgenic mice developed hepatocellular carcinomas. Many of the mouse livers were hyperplastic and filled with lipid. Other hepatic mRNAs with sequence motifs similar to apo-B mRNA were examined for this type of editing (i.e., cytidine deamination). One of these, tyrosine kinase, was edited in livers of transgenic mice but not of controls. This result demonstrates that other mRNAs can be edited by the overexpressed editing enzyme and suggests that aberrant editing of hepatic mRNAs involved in cell growth and regulation is the cause of the tumorigenesis. Finally, these findings compromise the potential use of APOBEC-1 for gene therapy to lower plasma levels of low density lipoproteins.

Chronic pain remains one of the most widespread and under treated medical conditions. Opioid drugs, such as morphine, are some of the most effective analgesics available. However, their utility for the treatment of chronic pain are limited by side effects including tolerance and dependence. Morphine induces its biological actions primarily through the G-protein coupled mu-opioid peptide receptor (MOP-R) [1], which is also the target of the endogenous opioids. However, unlike endogenous MOP-R ligands, morphine fails to promote substantial endocytosis of the MOP-R both in vitro [2–5] and in vivo [6–11]. Endocytosis of the MOP-R serves at least two important functions in regulating signal transduction. First, desensitization and endocytosis act as an “OFF” switch by uncoupling receptors from their cognate G protein. Second, endocytosis and receptor recycling serve as an “ON” switch, resensitizing receptors by recycling them to the plasma membrane where agonist can regain access to the receptors. Thus, due to poor endocytosis, both the OFF and ON function of the MOP-R are altered in response to morphine compared to endogenous ligands. To examine whether poor endocytosis contributes to morphine tolerance and dependence, we generated a knock-in mouse that expresses a mutant MOP-R that undergoes rapid endocytosis in response to morphine. Morphine remains an excellent antinociceptive agent in these mice. In addition, the mutant mice display substantially reduced antinociceptive tolerance and attenuated physical dependence. These data suggest that opioid drugs with pharmacological profile of morphine and the ability to promote endocytosis of the receptor could provide analgesia while having a reduced liability for the side effects of tolerance and dependence.