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Schaller, M.

Publications and source records attributed to Schaller, M..

9 recordsLinked to original sources

Efficacy of Centers of Biomedical Research Excellence (CoBRE) Grants to Build Research Capacity in Underrepresented States

Federal funding for research has immediate and long-term economic impact. Since federal research funding is regionally concentrated and not geographically distributed, the benefits are not fully realized in some regions of the country. The Established (previously Experimental) Program to Stimulate Competitive Research (EPSCoR) programs at several agencies, e.g. the National Science Foundation, and the Institutional Development Award (IDeA) program at the National Institutes of Health were created to increase competitiveness for funding in states with historically low levels of federal funding. The Centers of Biomedical Research Excellence (CoBRE) award program is a component of the IDeA program. The CoBRE grants support research core facilities to develop research infrastructure. These grants also support the research projects of junior investigators, under the guidance of mentoring teams of senior investigators, to develop human resources at these institutions. Few studies have assessed the effectiveness of these programs. This study examines the investment and outcomes of the CoBRE grants from 2000 through 2022. The maturation of junior investigators into independently funded principal investigators is comparable to other mentoring programs supported by NIH. The investment in research cores resulted in substantial research productivity, measured by publications. Despite the successes of individual investigators and increase research infrastructure and productivity, the geographic distribution of federal and NIH research dollars has not changed. These results will be informative in consideration of policies designed to enhance the geographic distribution of federal research dollars.

scientific communication and education↗

Wall teichoic acid substitution with glucose governs phage susceptibility of Staphylococcus epidermidis

The species- and clone-specific susceptibility of Staphylococcus cells for bacteriophages is governed by the structures and glycosylation patterns of wall teichoic acid (WTA) glycopolymers. The glycocodes of phage-WTA interaction in the opportunistic pathogen Staphylococcus epidermidis and in other coagulase-negative staphylococci (CoNS) have remained unknown. We report a new S. epidermidis WTA glycosyltransferase TagE whose deletion confers resistance to siphoviruses such as {Phi}E72 but enables binding of otherwise unbound podoviruses. S. epidermidis glycerolphosphate WTA was found to be modified with glucose in a tagE-dependent manner. TagE is encoded together with the enzymes PgcA and GtaB providing uridine diphosphate-activated glucose. {Phi}E72 transduced several other CoNS species encoding TagE homologs suggesting that WTA glycosylation via TagE is a frequent trait among CoNS that permits inter-species horizontal gene transfer. Our study unravels a crucial mechanism of phage-Staphylococcus interaction and of horizontal gene transfer and it will help in the design of anti-staphylococcal phage therapies. ImportancePhages are highly specific for certain bacterial hosts, and some can transduce DNA even across species boundaries. How phages recognize cognate host cells remains incompletely understood. Phages infecting members of the genus Staphylococcus bind to wall teichoic acid (WTA) glycopolymers with highly variable structures and glycosylation patterns. How WTA is glycosylated in the opportunistic pathogen Staphylococcus epidermidis and in other coagulase-negative Staphylococcus (CoNS) species has remained unknown. We describe that S. epidermidis glycosylates its WTA backbone with glucose and we identify a cluster of three genes, responsible for glucose activation and transfer to WTA. Their inactivation strongly alters phage susceptibility patterns, yielding resistance to siphoviruses but susceptibility to podoviruses. Many different CoNS species with related glycosylation genes can exchange DNA via siphovirus {Phi}E72 suggesting that glucose-modified WTA is crucial for interspecies horizontal gene transfer. Our finding will help to develop antibacterial phage therapies and unravel routes of genetic exchange.

microbiology↗

Training Doctoral Students in Critical Thinking and Experimental Design using Problem-based Learning

BackgroundTraditionally, doctoral student education in the biomedical sciences relies on didactic coursework to build a foundation of scientific knowledge and an apprenticeship model of training in the laboratory of an established investigator. Recent recommendations for revision of graduate training include the utilization of graduate student competencies to assess progress and the introduction of novel curricula focused on development of skills, rather than accumulation of facts. Evidence demonstrates that active learning approaches are effective. Several facets of active learning are components of problem-based learning (PBL), which is a teaching modality where student learning is self-directed toward solving problems in a relevant context. These concepts were combined and incorporated in creating a new introductory graduate course designed to develop scientific skills (student competencies) in matriculating doctoral students using a PBL format. MethodsEvaluation of course effectiveness was measured using the principals of the Kirkpatrick Four Level Model of Evaluation. At the end of each course offering, students completed evaluation surveys on the course and instructors to assess their perceptions of training effectiveness. Pre- and post-tests assessing students proficiency in experimental design were used to measure student learning. ResultsThe analysis of the outcomes of the course suggests the training is effective in improving critical thinking in experimental design. The course was well received by the students as measured by student evaluations (Kirkpatrick Model Level 1). Improved scores on post-tests indicate that the students learned from the experience (Kirkpatrick Model Level 2). A template is provided for the implementation of similar courses at other institutions. ConclusionsA problem-based learning platform appears effective in training newly matriculated graduate students in the required skills for designing experiments to test specific hypotheses, enhancing student preparation prior to initiation of their dissertation research.

scientific communication and education↗

Research Productivity and Training Support for Doctoral Students in the Biological and Biomedical Sciences

Training of doctoral students as part of the next generation of the biomedical workforce is essential for sustaining the scientific enterprise in the US. Training of doctoral students primarily occurs at institutions of higher education and these trainees comprise an important part of the workforce at these institutions. Federal investment in the support of doctoral students in the biological and biomedical sciences is distributed differently than the distribution of students across different types of institutions, e.g. Public vs Private. Institutions in states that historically receive less federal support for research also receive less support for doctoral student training. Analysis of F31 awardees at different types of institution reveal little difference in research productivity and subsequent receipt of additional NIH awards. Analysis of a large cohort of doctoral students at different types of institutions also reveal little difference in research productivity, with the exception of citations. Thus, training outcomes, which are related to the quality of the student and training environment, are similar across different institutions. Factors that correlate with F31 funding include R01 funding levels and program size. The findings suggest strategies for institutions to increase success at securing F31s and modification of policy to promote more equitable distribution of F31s across institutions.

scientific communication and education↗

Single-domain antibodies for targeting, detection and in vivo imaging of human CD4+ cells

The advancement of new immunotherapies necessitates appropriate probes to monitor the presence and distribution of distinct immune cell populations. Considering the key role of CD4+ T cells in regulating immunological processes, we generated novel single-domain antibodies (nanobodies, Nbs) that specifically recognize human CD4. After in depth analysis of their binding properties, recognized epitopes, and effects on T cell proliferation, activation and cytokine release, we selected CD4 Nbs that did not interfere with crucial T cell processes in vitro and converted them into immune tracers for non-invasive molecular imaging. By optical imaging, we demonstrate the ability of a high-affinity CD4-Nb to specifically visualize CD4+ cells in vivo using a xenograft model. Furthermore, time-resolved immune positron emission tomography (immunoPET) of a human CD4 knock-in mouse model showed rapid accumulation of 64Cu-radiolabeled CD4-Nb in CD4+ T cell-rich tissues. We propose that the CD4 Nbs presented here could serve as versatile probes for stratifying patients and monitoring individual immune responses during personalized immunotherapy in both cancer and inflammatory diseases.

immunology↗

Introducing Conflict Resolution and Negotiation Training into a Biomedical Sciences Graduate Curriculum

Analysis of the biomedical workforce and graduate education have produced recommendations for modifications of pre-doctoral training to broadly prepare trainees for wider ranging scientific careers. Increased exposure to career opportunities and development of training in professional skills is widely recommended, but details of implementation are not widely available. In alignment with these recommendations, we have incorporated professional skills training into the biomedical science graduate curriculum at West Virginia University. An important component of the training is developing conflict resolution and negotiation skills. This training will provide useful skills for academic careers, non-academic careers and life situations outside of the workplace. Conflict resolution/negotiation skills are also relevant in managing issues in diversity, equity and inclusivity. We report our experience in developing this component of the training program, provide an overview of the approach to delivery and practice of skills, and provide an analysis of the reception and effectiveness of the training.

scientific communication and education↗

The Costs and Benefits of a Modified Biomedical Science Workforce

Analyses of the biomedical research workforce, the biomedical research enterprise and its sustainability have identified a number of threats and offered many solutions to alleviate the problems. While, a number of these solutions have been implemented, one solution that has not been broadly adopted, despite being widely recommended, is to increase the number of staff scientists and reduce dependency on trainees. The perceived impediment of this is the cost. This paper explores the costs associated with laboratory personnel and the benefits, in terms of productivity, associated with different positions in the workforce. The results of this cost-benefit analysis depend upon the values assigned to different metrics of productivity by individuals and institutions. If first and senior author publications are the most important metrics of productivity, a trainee dependent workforce is much more cost effective. If total publications is the most valued metric of productivity, the cost effectiveness of trainee and staff scientists is reasonably equitable. This analysis provides data for consideration when making personnel decisions and for the continued discussion of modification of the biomedical research workforce. It also provides insight into the incentives for modification of the workforce at the grass roots, which must be considered by institutions genuinely committed to workforce modification to sustain the biomedical research enterprise.

scientific communication and education↗

FastTrack, A Strategy to Shorten Time to Degree

Recent reports express concern about the sustainability of the biomedical research enterprise in its current form. Recurring concerns include the predictability and sustainability of funding for research, regulatory burden and training the next generation in the biomedical workforce. One specific concern is the duration of training periods during pre-doctoral and post-doctoral studies. This article addresses the issue of time-to-degree (TTD) for doctorates. Many reports stress the importance of shortening the TTD, but provide no recommendations to achieve this goal. Herein, factors potentially affecting TTD are discussed and one mechanism that harmonizes undergraduate and graduate programs is proposed as a strategy to reduce the TTD.

scientific communication and education↗

Jagged-1 regulates Foxp3 expression and cytokine production in CD4+ T cells

Notch ligands are present during the interactions between T cells and dendritic cells (DC) and induce a myriad of effects that facilitate the activation of T cells, including the induction of T cell regulation, survival, and cytokine production. Although the ligands Delta-like 4 and Delta-like 1 are expressed as a function of DC activation, the notch ligand Jagged-1 is constitutively expressed on DC. We sought to determine the role of Jagged-1 in the interactions between CD4+ T cells and DC. We observed that Jagged-1 regulates Foxp3 expression, and Cd11cCre+Jaggedff mice have an altered expression of Foxp3 in effector cells that arise as a result of infection with the mycobacterium Bacille Calmette-Guerin. The observed changes in Foxp3 expression were correlated with an increase in cytokine production from cultures of antigen-stimulated draining lymph nodes.

immunology↗