Marek's Disease Virus VP22: Subcellular Localization and Characterization of Carboxyl Terminal Deletion Mutations

AbstractMarek's disease virus (MDV) is an alphaherpesvirus that causes T cell lymphoma and severe immunosuppression in chickens. The MDV UL49 gene, which encodes the tegument viral protein 22 (VP22), has been expressed as a green fluorescent protein (GFP) fusion protein in chicken embryonic fibroblasts to examine its subcellular localization. As with both human herpesvirus 1 and bovine herpesvirus 1VP22-GFP fusion proteins, the MDV VP22-GFP product binds to microtubules and heterochromatin. In addition, the MDV protein also binds to the centrosomes. During mitosis, VP22-GFP binds to sister chromatids, but dissociates from the centrosomes and the microtubules of the mitotic spindle. A series of VP22 carboxy terminal truncation mutants were constructed to define regions responsible for these binding properties. These mutants identified separable domains or motifs responsible for binding microtubules and heterochromatin

Tautomerization of H⁺KPGG: Entropic Consequences of Strong Hydrogen-Bond Networks in Peptides

Ion mobility spectrometry-mass spectrometry and quantum chemical calculations are used to determine the structures and stabilities of the singly protonated peptide H+KPGG. The two peaks making up the IMS distribution are shown to be tautomers differing by the location of the extra proton on either the lysine side chain or the N-terminus. The lysine-protonated tautomer is strongly preferred entropically while being disfavored in terms of the electronic energy and enthalpy. This relationship is shown, through comparison of all low-lying conformers of both tautomers, to be related to the strong hydrogen-bond network of the N-terminally protonated tautomer. A general relationship is demonstrated wherein stronger cross-peptide hydrogen-bond networks result in entropically disfavored conformers. Further effects of the H+KPGG hydrogen-bond network are probed by computationally examining singly and doubly methylated analogues. These results demonstrate the importance of the entropic consequences of hydrogen bonds to peptide stability as well as techniques for perturbing the hydrogen-bond network and folding preferences of peptides via minimal chemical modification

Faculty Email Exchanges

Email exchanges between University of Denver and Northwestern University on studies of John Evans and the Sand Creek Massacre

Mapping the Human Plasma Proteome by SCX-LC-IMS-MS

The advent of on-line multidimensional liquid chromatography-mass spectrometry has significantly impacted proteomic analyses of complex biological fluids such as plasma. However, there is general agreement that additional advances to enhance the peak capacity of such platforms are required to enhance the accuracy and coverage of proteome maps of such fluids. Here, we describe the combination of strong-cation-exchange and reversed-phase liquid chromatographies with ion mobility and mass spectrometry as a means of characterizing the complex mixture of proteins associated with the human plasma proteome. The increase in separation capacity associated with inclusion of the ion mobility separation leads to generation of one of the most extensive proteome maps to date. The map is generated by analyzing plasma samples of five healthy humans; we report a preliminary identification of 9087 proteins from 37,842 unique peptide assignments. An analysis of expected false-positive rates leads to a high-confidence identification of 2928 proteins. The results are catalogued in a fashion that includes positions and intensities of assigned features observed in the datasets as well as pertinent identification information such as protein accession number, mass, and homology score/confidence indicators. Comparisons of the assigned features reported here with other datasets shows substantial agreement with respect to the first several hundred entries; there is far less agreement associated with detection of lower abundance components

Adjustable Prone Trolley Design for People Suffering from Spinal Cord Injuries in Nepal

For people suffering from spinal cord injuries, it is important to stay active. However, with spinal cord injuries, the use of a wheelchair isn’t feasible. These patients require a prone trolley. A prone trolley is a horizontal pad with four wheels that a patient can maneuver and control while lying in a prone position. Our partner, International Nepal Fellowship (INF), deals directly with patients who suffer from spinal cord injuries on a daily basis. INF, a Christian, medical organization, manages a hospital in Pokhara, Nepal which specializes in treating patients with spinal cord injuries. The Nepal Prone Trolley Team’s goal is to provide our partner with a sustainable prone trolley design and create the required manufacturing documentation to enable them to produce the prone trolleys in country at their Green Pastures hospital. The team began our work by researching what a prone trolley is, how it functions and what is currently available. During the research, the team discovered that there weren’t many examples of a manually powered prone trolley or critical dimensions for ergonomics for manually powered trolleys. This drove the team to develop testing methods and preliminary designs specifically for INF. Various basic designs were considered, but, through communication with INF, a single design was chosen. Computer modeling of this design was used to decrease the overall weight of the trolley and simplify the frame. With most of the design finalized, the team is ready to begin prototyping next semester.https://mosaic.messiah.edu/engr2021/1012/thumbnail.jp

Achieving favourable customer outcomes through employee deviance

This study advances current knowledge by examining how employee deviance and customer participation during a single employee-customer exchange generate favourable customer responses. This work bridges the employee deviance stream with the service encounter literature and illustrates the importance of equity theory in deviant service exchanges between customers and employees. Moreover, results add to the ongoing debate on service nepotism by canvassing the consequences from the customer’s active participation in deviant exchanges which appears to enhance customer perceptions of the exchange. A 3x2 between-subjects experimental design was adopted which manipulates three types of pro-customer deviance along with customer’s participation (or not) to the exchange. The dependent variables capture three types of perceived customer justice (cognitive outcomes) and customer’s affective state (affective outcome). Findings illustrate that customers approve employees’ deviance for their own benefit while also indicate favourable outcomes from deviant exchanges with employees such as higher perceived justice and a more positive affective state. The article concludes with a discussion of the theoretical and managerial implications, limitations and research directions that emerge from this study

Adjustable Prone Trolley Design for People Suffering from Spinal Cords Injuries in Nepal

For people who suffer from spinal cord injuries in Nepal, rehabilitation and care are often difficult to receive, especially for those for whom fewer resources are available. Thankfully, International Nepal Fellowship (INF), a non-profit serving Nepal for nearly 70 years, aids patients with spinal cord injuries at Green Pastures Hospital and Rehabilitation Centre in Pokhara, Nepal. A crucial part of any rehabilitation is adequate exercise to improve circulation and prevent sores and muscular atrophy. Yet, due to the nature of the injury, using a traditional wheelchair is not an option to fulfill this need for those with spinal cord injuries. Therefore, Green Pastures uses prone trolleys so that these patients can exercise. A prone trolley is a horizontal cushioned board where the patient lies flat on their stomach and is able to move themselves using the wheels attached to the cushioned board. Despite the importance of the prone trolley, the trolleys at Green Pastures Hospital have a few critical issues. The major issue is that the prone trolleys are internationally imported, which not only means that delivery can take months, but also that the trolleys are also difficult to repair when damaged. Both these factors severely hamper Green Pastures Hospital’s ability to provide spinal cord injured patients with the care they need. The Nepal Prone Trolley team, a part of Messiah University Collaboratory, seeks to develop and design a fundamentally better prone trolley for INF. The goal of our project is to design a prone trolley that can be fabricated by the INF staff with locally sourced materials. The advantage of this new design is that it will be easier to obtain and can easily be repaired when needed. After creating a design that satisfies our goal and fulfills the criteria of a functional prone trolley as defined by INF, we were able to fabricate a prototype of the prone trolley using resources and techniques available in Pokhara. Moving forward, we will conduct testing and redesign the trolley so that our finalized prone trolley design will be able to transform how Green Pastures Hospital aids their spinal cord injury patients. Funding for this work provided by The Collaboratory for Strategic Partnerships and Applied Research.https://mosaic.messiah.edu/engr2022/1011/thumbnail.jp

Overtone Mobility Spectrometry: Part 2. Theoretical Considerations of Resolving Power

The transport of ions through multiple drift regions is modeled to develop an equation that is useful for an understanding of the resolving power of an overtone mobility spectrometry (OMS) technique. It is found that resolving power is influenced by a number of experimental variables, including those that define ion mobility spectrometry (IMS) resolving power: drift field (E), drift region length (L), and buffer gas temperature (T). However, unlike IMS, the resolving power of OMS is also influenced by the number of drift regions (n), harmonic frequency value (m), and the phase number (⌽) of the applied drift field. The OMS resolving power dependence upon the new OMS variables (n, m, and ⌽) scales differently than the square root dependence of the E, L, and T variables in IMS. The results provide insight about optimal instrumental design and operation. (J Am Soc Mass Spectrom 2009, 20, 738 -750) © 2009 American Society for Mass Spectrometry W hen a pulse of ions is injected into a buffer gas, different species separate under the influence of an electric field because of differences in their mobilities through the buffer gas Of note is the dependence of resolving power on the square root of the various parameters. This relationship imposes limits on the ultimate instrument performance. For example, doubling L does not double the resolving power; rather, a 2-fold increase in L (holding T and E constant) results in only ϳ40% increase in resolving power. In the present paper, we report modeling studies of ion transport through multiple drift regions to which the drift fields are applied at varying frequencies, the experimental setup used in overtone mobility spectrometry (OMS). The understanding that is gained from modeling allows us to develop a simple equation that can be used to estimate the OMS resolving power (R OMS ). The equation describing the OMS resolving power accounts for a number of geometrical OMS device configurations as well as those parameters used to define R IMS . However, these studies indicate that variation of the parameters which define R IMS (E, L, and T) have only a limited impact on the R OMS . Instead, the factors having the greatest influence on R OMS appear to be the number of phases for the system (i.e., the number of unique drift field application settings as well as the number of drift regions in a complete ion transmission/ elimination cycle, see below for complete description), the overall number of ion drift regions, and the drift field setting frequency (overtone number). A surprising result is the unit proportionality relationship between R OMS and the number of drift regions (in effect L) as well as the frequency suggesting the ability to garner much improved instrument performance (with respect to resolution) for proportionate changes when compared with IMS techniques. It is important to note that the comparisons to R IMS (with respect to L) described here are based on the use of a constant drift field. Equation 1 can be rewritten such that the product of L and E is denoted as the drift voltage (V). Extensive work has shown that increased resolving power can be obtained by optimizing V and Address reprint requests to Dr