bluuebunny/crossref_metadata_2025 huggingface dataset:
Implementing and Sustaining a Rural Interprofessional Clinical Education Program
Authors: Cragg Betty , Jelley Wilma , Burrows Mona , Dyer Kim
Published: March 2018

Background: After a successful pilot project introducing interprofessional (IP) clinical education in a rural hospital, expansion to other rural hospitals was attempted. Despite enthusiasm for the pilot project and funding, the university-based project team had difficulty persuading administrators and staff to become involved or to maintain the project. Of 9 institutions, 2 implemented and sustained the project for more than 2 years, 2 initiated but dropped it, and 5 declined.Methods and Findings: A qualitative, interpretive description study was conducted to identify facilitators and barriers to implementing an IP clinical education program in rural settings. Semi-structured interviews were conducted with representatives of organizations that sustained the project, dropped out, or never participated.Using the National Health Service Sustainability Model we identified the staff, organization, and process factors that affected the program implementation. Three staff roles were required for success: sponsor, champion, and gatekeeper. Organizational factors included infrastructure to identify participants and perceived project enhancement of organizational values. Process factors included organizational benefits, compatible priorities, and adaptability.Conclusions: Introduction of IP education to rural institutions requires complex combined factors. However, continuation of the project at two sites demonstrates that when IP education is valued and sustainability factors are present, staff will maintain it.
Oxygen and Ventilator Treatment: Perspectives on Interprofessional Collaboration in a Neonatal Intensive Care Unit
Authors: Solberg Marianne Trygg , Hansen Thor Willy Ruud , Bjørk Ida Torunn
Published: March 2018

Background: The aim of this study was to explore perspectives on the collaboration between physicians and nurses managing oxygen and ventilator treatment of sick infants in a Norwegian neonatal intensive care unit.Methods and Findings: We performed a qualitative study using focus groups. We found that interprofessional collaboration concerning newborns on mechanical ventilation lacked co-ordination and was unsystematic. This led to inadequate utilization of the medical and clinical competency of the nursing staff. Nurses and physicians approached decision-making differently, and there was limited flexibility and dynamics in the allocation of responsibility between the professionals.Conclusion: Findings from this study indicate that nurses and physicians have the opportunity to improve the quality of care by developing high-quality communication, formulating plans together, and improving the co-ordination of the ventilator treatment. Further studies should develop and test interventions based on the professionals’ perception of relevant co-ordination strategies to improve mechanical ventilation and oxygen treatment to premature and sick newborn infants.
Transdisciplinary Screening and Intervention for Nutrition, Swallowing, Cognition and Communication: A Case Study
Authors: Porter Judi
Published: March 2018

Background: Transdisciplinary health research and clinical practice is supported by numerous Australian health workforce documents and the broader transdisciplinary research literature. This research assessed the impact of early screening and limited intervention for nutrition, swallowing, cognition, and communication deficits in medical admissions in a large metropolitan hospital. Methods and Findings: Validated screening tools were selected and consensus for interventions were obtained by dietetic and speech pathology disciplines. Intensive training was undertaken to familiarize staff members with the screening documents and project scope. Ethics approval was obtained. Participants included 179 patients aged ≥65 years admitted to the emergency department or medical unit. The project significantly reduced referral time to both disciplines, and time to full assessment in dietetics but not speech pathology. Results found 43% of patients were malnourished or at risk of malnutrition, and 14 patients had oral intake ceased due to swallowing difficulties.Conclusions: This study has demonstrated that transdisciplinary screening and intervention may work within dietetics and speech pathology, providing an innovative extension to practice. Further alternatives using this model include the use of allied health assistants or less-experienced clinicians, while opportunities exist for transdisciplinary practices within other healthcare disciplines.
Translating Research into Practice: Impact of an Interprofessional Diabetes Education Model on Patient Health Outcomes
Authors: Shiyanbola Olayinka O. , Randall Becky , Lammers Cristina , Hegge Karly A. , Anderson Michelle
Published: March 2018

Background: Patient education programs encouraging diabetes self-management can improve clinical outcomes and lessen diabetes complications. This study implemented an innovative interprofessional student-led diabetes self-management and health promotion program for an underserved population and demonstrated an improvement in participant clinical outcomes and students’ understanding of interprofessional aspects of diabetes care.Methods and Findings: This community-based program was implemented at two sites that serve medically underserved individuals. Students from five health career professions led educational sessions designed to demonstrate critical components of diabetes self-management. The six-month longitudinal program covered topics within the Alphabet Strategy, including Advice, Blood pressure, Cholesterol, Diabetes control, Dental care, Diet, Eye care, Foot care, and Guardian drugs. Participants completed surveys evaluating diabetes knowledge, understanding of diabetes care, and health behaviours. Clinical values were collected before and after the program. Student surveys assessed their understanding of diabetes self-management. Upon completion of the program, all assessments were repeated to determine if there were improvements in outcomes. Thirty-eight participants and thirty students completed the study. There were significant improvements in participants’ diabetes knowledge, understanding of diabetes management, and clinical outcomes. There were significant improvements in the students’ ability to educate patients about foot care, eye care, and guardian drugs, as well as increased awareness of the role of each health profession in diabetes care.Conclusions: This interprofessional health promotion model showed significant improvements in patient and student outcomes. This innovative student-led program could be implemented in other settings and for the management of other chronic diseases.
Deeper Learning through Service: Evaluation of an Interprofessional Community Service-Learning Program for Pharmacy and Medicine Students
Authors: Clark Megan , McKague Meredith , Ramsden Vivian R. , McKay Shari
Published: March 2018

Abstract   Background  This Community Service-Learning Project (CSLP) at the University of Saskatchewan is designed to help students develop patient-centred care practices in urban underserved settings.  First-year medical and pharmacy students partner interprofessionally to both learn and serve, working with community-based organizations (CBOs) that primarily serve either low-income or newcomer residents of Saskatoon. Since the CSLP’s pilot year in 2005-2006, 98 first-year medical and pharmacy students have participated in the CSLP.       Methods and Findings  We evaluated the outcomes and processes of the CSLP since the 2006-2007 year, using mixed methods: end-of-project questionnaires; document analysis looking for key and recurrent themes; end-of-project semi-structured interviews with CBO coordinators and clients. We examined students’ experiences, including satisfaction, achievement of learning objectives, learning processes, and perceived outcomes. Students’ main learning outcomes related to client-centered approach, interprofessional attitudes and skills, and personal development. Various learnings related to program processes are reported.   Conclusions  Our evaluation reinforced findings from the literature on both interprofessional education and community service-learning, as well uncovering some new findings.   Students described a transformative learning experience that helped them begin to develop understanding and skills to work more effectively with clients in urban underserved settings.
Interprofessional Experiences at a Student-run Clinic: Who Participates and What Do They Learn?
Authors: Ambrose Emma , Baker Dana , Mahal Inderveer , MicFlikier Aaron , Holmqvist Maxine
Published: March 2018

Background: Student-run Clinics (SRCs) are student-driven, interprofessional community service-learning primary care initiatives in which students of different disciplines work collaboratively under the supervision of licensed healthcare professionals. Despite their increasing prominence and promise as vehicles for interprofessional education, little is known about the characteristics of students or mentors who participate in these initiatives. Methods: A quality improvement review was conducted by members of an interprofessional, student-run clinic based on data collected in the first 3 years of clinic operation. Program records and anonymous feedback forms were examined for information regarding student and mentor characteristics (e.g., discipline, frequency of participation) and information regarding service provider satisfaction and recommendations.  Findings: The STAR Clinic had low student retention with the majority of students attending only one clinic shift. There was also limited student and mentor diversity, with medicine and nursing most highly represented. Qualitative information highlighted areas of strength and opportunities for improvement. Conclusions: Recruitment and retention of students and mentors should be a priority for SRCs. Efforts devoted to increasing interprofessional diversity would likely benefit clients and allow for a more holistic approach to person-centred care.
Observe, Coach, Assist, and Report: An Emerging Framework for Integrating Unregulated Healthcare Providers into Interdisciplinary Healthcare Teams
Authors: Giosa Justine , Holyoke Paul , Bender Danielle , Tudge Sandra , Gifford Wendy
Published: March 2018

Background: Unregulated healthcare providers known as personal support workers (PSWs) provide the majority of home care services in Ontario, Canada. However, there is little direction to guide their activities as members of interdisciplinary healthcare teams. The purpose of this study was to explore and describe the role of PSWs in interdisciplinary evidence-based stroke care.Methods and Findings: A concurrent triangulation mixed-methods design was used. Data sources included surveys (N = 270), chart audits (N = 234), interviews (N = 28), focus groups (N = 7), textbook review, an advisory committee (N = 14), and knowledge fairs (N = 112). PSWs can participate in team-based stroke care by observing vital information about clients in their homes, coaching clients to follow care plans, assisting to implement recommendations made by other healthcare providers, and reporting client progress, challenges, needs, and preferences to the healthcare team.Conclusions: The Observe, Coach, Assist, and Report (OCAR) themes have the potential to be used as a framework to guide improvements in intra-team communication, information sharing, and awareness of the PSW role, in order to support a more integrated home care experience for clients and families. Next steps include pilot testing the OCAR framework at the point of care in various settings to enhance interdisciplinary collaboration that is inclusive of PSWs.
Training Spiritual Care in Palliative Care in Teaching Hospitals in the Netherlands (SPIRIT-NL): A Multicentre Trial.
Authors: Van De Geer Joep , Zock Hetty , Leget Carlo , Veeger Nic , Prins Jelle , Groot Marieke , Vissers Kris
Published: March 2018

Background: In the Netherlands, the spiritual dimension in healthcare became marginal in the second part of the twentieth century. In the Dutch healthcare system, palliative care is not a medical specialization and teaching hospitals do not have specialist palliative care units with specialized palliative care teams. Palliative care in these hospitals is delivered by healthcare professionals in general departments (mainly curative focused ones), and is based on multidisciplinary guidelines supported by palliative care consultation teams. A national multidisciplinary guideline on spiritual care is included, but standardized training based on this guideline still lacks. Implementation of this guideline is expected to have a positive effect on quality of care but is in an early state, the role of the specialists in this field—the healthcare chaplains—is developing. The objective of this article is to present the protocol of this study and stimulate discussion about methods of research on spirituality and spiritual care.Methods and Findings: This action research study is planned as an explorative multicentre trial. Healthcare chaplains of ten teaching hospitals will offer training onspiritual care in palliative care for healthcare professionals. What is the effect of this intervention on the competences of clinical teams? What is the effect on the perceived care and treatment as experienced by patients? The effects of the intervention on the competences of the clinicians will be measured once pre-study and twice post-study. Effects on patients’ physical symptoms and spiritual distress, and the perceived focus of caregivers on their spiritual needs or existential questions will also be measured pre- and post-study.
The Use of a Modified Delphi Technique to Inform the Development of Best Practice in Interprofessional Training for Collaborative Primary Healthcare
Authors: Bentley Michael , Kerr Rohan , Powell Susan
Published: March 2018

Background: Primary healthcare (PHC) education and training is directed to a diverse range of health professionals at undergraduate, postgraduate, and professional levels. Increasing emphasis is being placed on PHC professionals working together in delivering better care and improving patient outcomes. This article reports on using a modified Delphi technique to determine the level of consensus on a series of statements across four domains of interprofessional education (IPE) for collaborative practice: big picture, organization, capabilities, teaching, and learning. Methods and Findings: The modified Delphi technique used three Delphi rounds: the first round comprising workshops, interviews, or online survey; the remaining rounds used online surveys. A panel of 56 PHC medical, nursing, allied health, and workforce experts participated. There was consensus on a set of capabilities for interprofessional learning outcomes and on a range of teaching and learning strategies. Areas for further consideration included identifying interprofessional training opportunities through continuing professional development, and tailoring team-based approaches to diverse PHC settings. Conclusion: The modified Delphi technique used in this project demonstrated a successful engagement of a heterogeneous panel of PHC experts. The principles of IPE for collaborative practice and strategies for delivering interprofessional training could apply across various PHC settings.
The Impact of Hidden Curriculum in Wilderness-Based Educational Events on Interprofessional Competencies: A Mixed-Method Study
Authors: Reade Maurianne , Maar Marion , Cardinal Nicole , Boesch Lisa , Lacarte Sara , Rollins Tara , Jeeves Nicholas
Published: March 2018

Background: The purpose of this study was to determine if interprofessional skills, attitudes, and behaviours could be learned during an austere medicine educational activity where interprofessionalism remained within the informal and hidden curriculum.Methods and Findings: We used a mixed-methods approach to examine the potential acquisition of interprofessional competencies during wilderness medicine educational events. Thirty-four participants, over two events, completed interprofessional learner contracts, audio diary entries between patient scenarios, and the Interprofessional Collaborative Competency Attainment Survey (ICCAS) using a retrospective pre-test/post-test design. Audio diary entries showed the reflection that took place between scenarios during the orienteering portion of the event and the adjustments toward interprofessionalism that took place. Both the survey and audio diaries confirmed that participants perceived an improvement of their interprofessional competencies after the WildER Med event.Conclusions: The outcomes confirm that interprofessional competencies can be developed during a learning event such as WildER Med, where the interprofessional curriculum is hidden. Austere medicine, which is at the base of this learning event, represents an opportunity for the further understanding and exploration of interprofessional education.
Roles and Responsibilities: Asking Nurses and Physicians What They Know, Do Not Know and Want to Know about the Other's Profession
Authors: Moriel Dordie , Felix Karla , Quinlan Patricia
Published: March 2018

Background: In 2015, an Institute of Medicine (IOM) report acknowledged that interprofessional education (IPE) had focused on academic learning yet had not been well assimilated into clinical practice. The aim of this study was to gather data from practicing clinicians to inform a curriculum that could be integrated into practice environment educational regimens.Methods and Findings: A qualitative description approach was utilized to analyze data gathered via focus groups conducted with practicing nurses and physicians. Participants were asked to describe what they knew, did not know, and wanted to know about each others profession, and what they felt would be the best method of delivery for this information. Findings indicate a lack of understanding of the roles and responsibilities of the other profession and genuine interest in learning more.Conclusions: Integrating IPE into practice environment education is of interest and would be beneficial to healthcare professionals for improving patient care, safety, and professional rapport.
An Autoethnographic Study of Interprofessional Education Partnerships
Authors: Hurst Samantha , Macauley Karen A. , Awdishu Linda , Sweeney Kathleen M , Hutchins Sophie S , Namba Jennifer M , Johnson Michelle L , Wallace Peggy A , Garman Karen A , Zheng Amy M
Published: March 2018

Background: Thiis qualitative longitudinal study describes an Interprofessional Education (IPE) collaboration between a public university with medical and pharmacy schools and a private, non-affiliated university with a nursing school. The study explores the dynamics of the IPE partnership and lessons learned over a three-year period in which members of the collaborative directed three IPE simulations.Methods and Findings: An autoethnographic inquiry technique was used to interview eight collaborators who designed and implemented a large-scale IPE simulation for approximately 300 students and 100 faculty members annually for three years. Two, 90-minute group narrative interviews were conducted and audio recorded for transcription and analysis. Five themes emerged: Natural Collaboration, Shared Vision and Commitment, Integrations and Synergy, All Hands on Deck, and Lasting Foundations. Collaborators agreed the joint effort was a positive experience with multidimensional returns on investment. They applied teamwork competencies to build the partnership, develop the IPE simulation, and overcome implementation challenges.Conclusions: Thiis article provides readers with the opportunity to learn from those who have been intimately involved in the design and implementation of a large-scale IPE collaboration to enhance the shared learning process for health students and faculty. Findings highlight the complexity of building an IPE collaborative and the necessity to build partnerships with facilitators committed to communication.
Auditor and FASB Responsibilities for Representing Underlying Economics—What U.S. Standards Actually Say
Authors: Palmrose Zoe-Vonna , Kinney William R.
Published: March 2018

SYNOPSIS

Does the auditor's responsibility under U.S. authoritative guidance extend to providing assurance of financial reporting quality—specifically whether financial statements “faithfully reflect the firm's underlying economics”—after the auditor has concluded that financial statements are fairly presented in conformity with GAAP, in all material respects? The question arises because DeFond and Zhang (2014) state such a view and cite U.S. authoritative guidance as support. We review SEC, PCAOB, and FASB guidance and other sources and find no authoritative support for DeFond and Zhang's (2014) view. We also find that the PCAOB explicitly recognizes the lack of objective criteria that would be necessary to evaluate financial reporting quality beyond application of GAAP to events and transactions. Further, we find no evidence that practicing auditors do (separately) assess or assure that financial statements faithfully reflect the entire firm's underlying economics. Overall, these findings suggest DeFond and Zhang (2014) express a personal (and impracticable) normative view and not the auditor's actual responsibility or practice under extant U.S. standards. More broadly, results reinforce the importance of defining and measuring audit quality based on the auditor's actual responsibilities and the importance of accurately characterizing authoritative guidance and practice for scholarship regarding complex and multifaceted matters, including audit quality.
In Vivo Imaging of Peripheral Benzodiazepine Receptors in Mouse Lungs: A Biomarker of Inflammation
Authors: Hardwick Matthew J. , Chen Ming-Kai , Baidoo Kwamena , Pomper Martin G. , Guilarte Tomás R.
Published: March 2018

The ability to visualize the immune response with radioligands targeted to immune cells will enhance our understanding of cellular responses in inflammatory diseases. Peripheral benzodiazepine receptors (PBR) are present in monocytes and neutrophils as well as in lung tissue. We used lipopolysaccharide (LPS) as a model of inflammation to assess whether the PBR could be used as a noninvasive marker of inflammation in the lungs. Planar imaging of mice administrated 10 or 30 mg/kg LPS showed increased [123I]-( R)-PK11195 radioactivity in the thorax 2 days after LPS treatment relative to control. Following imaging, lungs from control and LPS-treated mice were harvested for ex vivo gamma counting and showed significantly increased radioactivity above control levels. The specificity of the PBR response was determined using a blocking dose of nonradioactive PK11195 given 30 min prior to radiotracer injection. Static planar images of the thorax of nonradioactive PK11195 pretreated animals showed a significantly lower level of radiotracer accumulation in control and in LPS-treated animals ( p < .05). These data show that LPS induces specific increases in PBR ligand binding in the lungs. We also used in vivo small-animal PET studies to demonstrate increased [11C]-( R)-PK11195 accumulation in the lungs of LPS-treated mice. This study suggests that measuring PBR expression using in vivo imaging techniques may be a useful biomarker to image lung inflammation.
High-affinity Near-infrared Fluorescent Small-molecule Contrast Agents for In Vivo Imaging of Prostate-specific Membrane Antigen
Authors: Humblet Valerie , Lapidus Rena , Williams Larry R. , Tsukamoto Takashi , Rojas Camilo , Majer Pavel , Hin Bunda , Ohnishi Shunsuke , De Grand Alec M. , Zaheer Atif , Renze Jürgen T. , Nakayama Akira , Slusher Barbara S. , Frangioni John V.
Published: March 2018

Surgical resection remains a definitive treatment for prostate cancer. Yet, prostate cancer surgery is performed without image guidance for tumor margin, extension beyond the capsule and lymph node positivity, and without verification of other occult metastases in the surgical field. Recently, several imaging systems have been described that exploit near-infrared (NIR) fluorescent light for sensitive, real-time detection of disease pathology intraoperatively. In this study, we describe a high-affinity (9 nM), single nucleophile-containing, small molecule specific for the active site of the enzyme PSMA. We demonstrate production of a tetra-sulfonated heptamethine indocyanine NIR fluorescent derivative of this molecule using a high-yield LC/MS purification strategy. Interestingly, NIR fluorophore conjugation improves affinity over 20-fold, and we provide mechanistic insight into this observation. We describe the preparative production of enzymatically active PSMA using a baculovirus expression system and an adenovirus that co-expresses PSMA and GFP. We demonstrate sensitive and specific in vitro imaging of endogenous and ectopically expressed PSMA in human cells and in vivo imaging of xenograft tumors. We also discuss chemical strategies for improving performance even further. Taken together, this study describes nearly complete preclinical development of an optically based small-molecule contrast agent for image-guided surgery.
A Methodology for Registration of a Histological Slide and In Vivo MRI Volume Based on Optimizing Mutual Information
Authors: Meyer Charles R. , Moffat Bradford A. , Kuszpit Kyle K. , Bland Peyton L. , Mckeever Paul E. , Johnson Timothy D. , Chenevert Thomas L. , Rehemtulla Alnawaz , Ross Brian D.
Published: March 2018

We present a method for registering histology and in vivo imaging that requires minimal microtoming and is automatic following the user's initialization. In this demonstration, we register a single hematoxylin-and-eosin-stained histological slide of a coronal section of a rat brain harboring a 9L gliosarcoma with an in vivo 7T MR image volume of the same brain. Because the spatial resolution of the in vivo MRI is limited, we add the step of obtaining a high spatial resolution, ex vivo MRI in situ for intermediate registration. The approach taken was to maximize mutual information in order to optimize the registration between all pairings of image data whether the sources are MRI, tissue block photograph, or stained sample photograph. The warping interpolant used was thin plate splines with the appropriate basis function for either 2-D or 3-D applications. All registrations were implemented by user initialization of the approximate pose between the two data sets, followed by automatic optimization based on maximizing mutual information. Only the higher quality anatomical images were used in the registration process; however, the spatial transformation was directly applied to a quantitative diffusion image. Quantitative diffusion maps from the registered location appeared highly correlated with the H&E slide. Overall, this approach provides a robust method for coregistration of in vivo images with histological sections and will have broad applications in the field of functional and molecular imaging.
In Vivo Monitoring of Pancreatic β-Cells in a Transgenic Mouse Model
Authors: Smith Steven J. , Zhang Hongbing , Clermont Anne O. , Powers Alvin C. , Kaufman Dixon B. , Purchio Anthony F. , West David B.
Published: March 2018

We generated a transgenic mouse model ( RIP-luc) for the in vivo monitoring of pancreatic islet mass and function in response to metabolic disease. Using the rat insulin promoter fused to firefly luciferase, and noninvasive technology to detect luciferase activity, we tracked changes in reporter signal during metabolic disease states and correlated the changes in luciferase signal with metabolic status of the mouse. Transgene expression was found to be specific to the pancreatic islets in this transgenic model. Basal transgene expression was tracked in male and female mice fed either a chow or a high-fat diet and in response to treatment with streptozotocin. Pancreatic bioluminescent signal increased in mice fed a high-fat diet compared with chow-fed animals. In a model of chemically induced diabetes, the bioluminescent signal decreased in accordance with the onset of diabetes and reduction of islet β-cell number. Preliminary studies using islets transplanted from this transgenic model suggest that in vivo image analysis can also be used to monitor transplanted islet viability and survival in the host. This transgenic model is a useful tool for in vivo studies of pancreatic β-cells and as a donor for islet transplantation studies.
Normalized Transillumination of Fluorescent Proteins in Small Animals
Authors: Zacharakis Giannis , Shih Helen , Ripoll Jorge , Weissleder Ralph , Ntziachristos Vasilis
Published: March 2018

We investigated the capacity of normalized transillumination methods in imaging fluorescent proteins in visible light, in phantoms and in live mice. We demonstrate significant imaging improvements over epi-illumination imaging, as commonly applied today. Of particular importance is the significant betterment in contrast achieved, due to minimization of the influence of autofluorescence and the enhancement of depth sensitivity compared to epi-illumination imaging. Although normalized transillumination does not match the accuracy and quantification capacity of tomographic imaging, it nevertheless attains key advantages over other planar optical imaging methods while preserving implementation simplicity. Due to the balance achieved between simplicity and accuracy, normalized transillumination approaches could serve as an important alternative molecular imaging method.
Application of Ultrasound to Selectively Localize Nanodroplets for Targeted Imaging and Therapy
Authors: Dayton Paul A. , Zhao Shukui , Bloch Susannah H. , Schumann Pat , Penrose Kim , Matsunaga Terry O. , Zutshi Reena , Doinikov Alexander , Ferrara Katherine W.
Published: March 2018

Lipid-coated perfluorocarbon nanodroplets are submicrometer-diameter liquid-filled droplets with proposed applications in molecularly targeted therapeutics and ultrasound (US) imaging. Ultrasonic molecular imaging is unique in that the optimal application of these agents depends not only on the surface chemistry, but also on the applied US field, which can increase receptor-ligand binding and membrane fusion. Theory and experiments are combined to demonstrate the displacement of perfluorocarbon nanoparticles in the direction of US propagation, where a traveling US wave with a peak pressure on the order of megapascals and frequency in the megahertz range produces a particle translational velocity that is proportional to acoustic intensity and increases with increasing center frequency. Within a vessel with a diameter on the order of hundreds of micrometers or larger, particle velocity on the order of hundreds of micrometers per second is produced and the dominant mechanism for droplet displacement is shown to be bulk fluid streaming. A model for radiation force displacement of particles is developed and demonstrates that effective particle displacement should be feasible in the microvasculature. In a flowing system, acoustic manipulation of targeted droplets increases droplet retention. Additionally, we demonstrate the feasibility of US-enhanced particle internalization and therapeutic delivery.
Noninvasive Optical Imaging of Ovarian Metastases Using Cy5-labeled RAFT-c(-RGDfK-)4
Authors: Jin Zhao-hui , Josserand Veronique , Razkin Jesus , Garanger Elisabeth , Boturyn Didier , Favrot Marie-Christine , Dumy Pascal , Coll Jean-luc
Published: March 2018

Our group has developed a new molecular tool based on the use of a regioselectively addressable, functionalized template (RAFT) scaffold, where four cyclic (Arg-Gly-Asp) (cRGD) peptide motifs were grafted. The aim of this study was to determine whether RAFT-c(-RGDfK-)4 combined with optical imaging could allow noninvasive detection of deep ovarian metastases. Human ovarian adenocarcinoma IGROV1 cells expressing low levels of integrin αvβ3 (the main receptor for the cRGD peptide) were used for in vitro and in vivo assays in combination with Cy5-labeled RAFT-c(-RGDfK-)4, cRGD, or RAFT-c(-RβADfK-)4. In vivo fluorescence imaging was performed on subcutaneous (SC) tumors and intraperitoneal IGROV1 metastases in nude mice. The accumulation of RGD-Cy5 conjugates in cultured cells or in tumor tissues was examined using confocal laser scanning microscopy. RAFT-c(-RGDfK-)4 exhibited stronger staining in vitro, enhanced tumor-to-background ratio for SC tumors, and allowed early detection of 1- to 5-mm large intraabdominal nodules using noninvasive optical imaging. Histological study revealed that RAFT-c(-RGDfK-)4 accumulated into tumor neovasculature but also into tumor cells. Our data demonstrate that a Cy5-labeled RAFT-c(-RGDfK-)4 is an efficient optical probe for early and noninvasive tumor detection.
Second-Generation Triple Reporter for Bioluminescence, Micro–Positron Emission Tomography, and Fluorescence Imaging
Authors: Kesarwala Aparna H. , Prior Julie L. , Sun Jinwu , Harpstrite Scott E. , Sharma Vijay , Piwnica-Worms David
Published: March 2018

Bioluminescence, positron emission tomography (PET), and fluorescence modalities are currently available for noninvasive imaging in vivo, each with its own merits. To exploit the combined strengths of each and facilitate multimodality imaging, we engineered a dual-reporter construct in which firefly luciferase (FLuc) and a 12–amino acid nonstructural linker were fused in frame to the N-terminus of a mutant herpes simplex virus thymidine kinase (mNLS-SR39TK) kinetically enhanced for positron emission tomography (PET). Furthermore, a triple-reporter construct was developed in which monster green fluorescent protein (MGFP), a recently available enhanced fluorescent protein, was introduced into the fusion vector downstream of an internal ribosome entry site (IRES) to allow analysis by fluorescence microscopy or flow cytometry without compromising the specific activities of the upstream fusion components. FLuc bioluminescence was measured with a cooled charge-coupled device camera and mNLS-SR39TK activity by 9-[4-[18F]fluoro-3-(hydroxymethyl) butyl guanine (18F-FHBG) microPET or 3H-penciclovir net accumulation. Importantly, HeLa cells transiently transfected with the FLuc-mNLS-SR39TK-IRES-MGFP triple reporter retained the same specific activities of the FLuc-mNLS-SR39TK heteroenzyme and the individual unfused enzymes with no change in protein half-lives. The presence of the IRES-MGFP modestly decreased upstream heteroprotein expression. In living mice, somatic gene transfer of a ubiquitin promoter-driven FLuc-mNLS-SR39TK-IRES-MGFP plasmid showed a > 1,000-fold increase in liver photon flux and a > 2-fold increase in liver retention of 18F-FHBG by microPET compared with mice treated with control plasmid. Multifocal hepatocellular fluorescence was readily observed by standard confocal microscopy. This second-generation triple reporter incorporating enhanced components enables bioluminescence, PET, and fluorescence imaging of cells and living animals.
Application of Surface Roughness Analysis on Micro–Computed Tomographic Images of Bone Erosion: Examples Using a Rodent Model of Rheumatoid Arthritis
Authors: Silva Matthew D. , Ruan Jason , Siebert Elizabeth , Savinainen Anneli , Jaffee Bruce , Schopf Lisa , Chandra Sudeep
Published: March 2018

Quantifying the bone erosion in preclinical models of rheumatoid arthritis is valuable for the evaluation of drug treatments. This study introduces a three-dimensional method for bone surface roughness measurement from micro–computed tomographic data obtained from rats subjected to collagen-induced arthritis (CIA), in which the degree of bone erosion is related to the severity and the duration of the disease. In two studies of rat CIA, the surface roughness of the talus bone following 21 days of disease increased 559% and 486% from the control group. At 41 days following disease induction, the roughness of the bone surface increased 857% above baseline. The roughness of the control samples was similar from each study (less than 4% different), demonstrating the robustness of the algorithm. Treatment with methotrexate at 0.1 mg/kg daily demonstrated significant protection from bone erosion, whereas the 0.05 mg/kg daily dose was not efficacious (98% versus 22% inhibition of roughness-measured bone erosion). The main advantage of such an algorithm is demonstrated in the preclinical drug study of rat CIA with methotrexate treatment, indicating the immediate utility of this approach in drug development studies.
Quantitative Imaging of Cell-Permeable Magnetic Resonance Contrast Agents Using X-Ray Fluorescence
Authors: Endres Paul J. , MacRenaris Keith W. , Vogt Stefan , Allen Matthew J. , Meade Thomas J.
Published: March 2018

The inability to transduce cellular membranes is a limitation of current magnetic resonance imaging probes used in biologic and clinical settings. This constraint confines contrast agents to extracellular and vascular regions of the body, drastically reducing their viability for investigating processes and cycles in developmental biology. Conversely, a contrast agent with the ability to permeate cell membranes could be used in visualizing cell patterning, cell fate mapping, gene therapy, and, eventually, noninvasive cancer diagnosis. Therefore, we describe the synthesis and quantitative imaging of four contrast agents with the capability to cross cell membranes in sufficient quantity for detection. Each agent is based on the conjugation of a Gd(III) chelator with a cellular transduction moiety. Specifically, we coupled Gd(III)–diethylenetriaminepentaacetic acid DTPA and Gd(III)–1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid with an 8–amino acid polyarginine oligomer and an amphipathic stilbene molecule, 4-amino-4'-( N,N-dimethylamino)stilbene. The imaging modality that provided the best sensitivity and spatial resolution for direct detection of the contrast agents is synchrotron radiation x-ray fluorescence (SR-XRF). Unlike optical microscopy, SR-XRF provides two-dimensional images with resolution 103 better than 153Gd gamma counting, without altering the agent by organic fluorophore conjugation. The transduction efficiency of the intracellular agents was evaluated by T1 analysis and inductively coupled plasma mass spectrometry to determine the efficacy of each chelate-transporter combination.
Targeted Photodynamic Therapy Agent with a Built-In Apoptosis Sensor for in Vivo Near-Infrared Imaging of Tumor Apoptosis Triggered by its Photosensitization in Situ
Authors: Stefflova Klara , Chen Juan , Li Hui , Zheng Gang
Published: March 2018

Imaging apoptotic cells or tissues after cancer therapy in situ would be a very useful tool for assessing proper treatment conditions and therapeutic outcome. By combining therapeutic and imaging functions, we have designed a multifunctional, membrane-permeable, and cancer-specific agent that triggers and images apoptosis in targeted cells. We chose photodynamic therapy (PDT) as an appropriate cancer treatment modality and caspase 3 as an apoptosis-specific imaging target. This targeted photodynamic therapy agent with a built-in apoptosis sensor (TaBIAS) induces photodamage only to target cells and simultaneously identifies those that are apoptotic by its near-infrared fluorescence. It contains a fluorescent photosensitizer used as an anticancer drug and a cancer-associated folate receptor homing molecule connected to a caspase 3 cleavable peptide linker that has a fluorescence quencher on the opposing site. We demonstrated that PDT-triggered cleavage of the peptide linker by caspase 3, one of the key executioner caspases, results in a detectable increase in fluorescence in folate receptor–overexpressing cancer cells and tumors. The presence of apoptosis was confirmed in vitro by flow cytometry and ex vivo by Apoptag assay, supporting the ability of TaBIAS to specifically induce and image apoptosis in situ.
In Vivo Detection of c-MET Expression in a Rat Hepatocarcinogenesis Model Using Molecularly Targeted Magnetic Resonance Imaging
Authors: Towner Rheal A. , Smith Nataliya , Tesiram Yasvir A. , Abbott Andrew , Saunders Debbie , Blindauer Rebecca , Herlea Oana , Silasi-Mansat Robert , Lupu Florea
Published: March 2018

The multifunctional growth factor scatter factor/hepatocyte growth factor and its tyrosine kinase receptor, c-MET, have been implicated in the genesis and malignant progression of numerous human malignancies, including hepatocellular carcinomas. The incidence of hepatocellular carcinomas in the United States has increased noticeably over the past two decades and is listed as the fifth major cancer in men worldwide. In this study, we used a choline-deficient l-amino acid (CDAA)-defined rat hepatocarcinogenesis model to visualize increased in vivo expression of the c-MET antigen in neoplastic lesion formation with the use of a super paramagnetic iron oxide (SPIO)–anti-c-MET molecularly targeted magnetic resonance imaging (MRI) contrast agent. SPIO–anti-c-MET was used for the first time to detect overexpression of c-MET in neoplastic nodules and tumors within the livers of CDAA-treated rats, as determined by a decrease in MRI signal intensity and a decrease in regional T2 values. Specificity for the binding of the molecularly targeted anti-c-MET contrast agent was determined using rat hepatoma (H4-II-E-C3) cell cultures and immunofluorescence microscopic imaging of the targeting agents within neoplastic liver tissue 1 to 2 hours following intravenous administration of SPIO–anti-c-MET and MRI investigation. This method has the ability to visualize in vivo the overexpression of c-MET at early developmental stages of tumor formation.
In Vivo Noninvasive Optical Imaging of Receptor-Mediated RGD Internalization Using Self-Quenched Cy5-Labeled RAFT-c(-RGDfK-)4
Authors: Jin Zhao-Hui , Razkin Jesus , Josserand Veronique , Boturyn Didier , Grichine Alexeï , Texier Isabelle , Favrot Marie-Christine , Dumy Pascal , Coll Jean-Luc
Published: March 2018

We reported that regioselectively addressable functionalized template (RAFT)-c(-RGDfK-)4 presenting four cyclic (Arg-Gly-Asp) (cRGD) peptides targets integrin aVb3 with an improved specificity compared with monomeric cRGD. In this study, we improved this vector by creating a “stealth” molecule in which a fluorescence quencher (Q) is linked to Cy5 via a disulfide bond (-SS-). RAFT-c(-RGDfK-)4-Cy5-SS-Q fluorescence is quenched unless activated by reduction during internalization. RAFT-c(-RGDfK-)4-Cy5-SS-Q fluorescence was negligible when compared with the control but totally recovered after cleavage of the disulfide bridge. Confocal microscopy showed that only the intracellular Cy5 signal could be detected using RAFT-c(-RGDfK-)4-Cy5-SS-Q, confirming that uncleaved extracellular molecules are not visible. Whole-body imaging of mice bearing subcutaneous tumors injected intravenously with RAFT-c(-RGDfK-)4-Cy5-SS-Q showed a very significant enhancement of the fluorescent contrast in tumors compared with the unquenched molecule. Histology of the tumor confirmed the intracellular accumulation of Cy5. These results demonstrate that the presence of a labile disulfide bridge between the targeting vector and a drug mimetic is an efficient way to deliver a dye, or a drug, intracellularly. In addition, this quenched RAFT-c(-RGDfK-)4-Cy5-SS-Q probe is a very powerful vector for imaging tumor masses and investigating in vivo RGD-mediated internalization.
Continuous Delivery of D-Luciferin by Implanted Micro-osmotic Pumps Enables True Real-Time Bioluminescence Imaging of Luciferase Activity in Vivo
Authors: Gross Shimon , Abraham Ute , Prior Julie L. , Herzog Erik D. , Piwnica-Worms David
Published: March 2018

Bioluminescence imaging (BLI) of luciferase reporters in small animal models offers an attractive approach to monitor regulation of gene expression, signal transduction, and protein-protein interactions, as well as following tumor progression, cell engraftment, infectious pathogens, and target-specific drug action. Conventional BLI can be repeated within the same animal after bolus reinjections of a bioluminescent substrate. However, intervals between image acquisitions are governed by substrate pharmacokinetics and excretion, therefore restricting temporal resolution of reinjection protocols to the order of hours, limiting analyses of processes in vivo with short time constants. To eliminate these constraints, we examined use of implanted micro-osmotic pumps for continuous, long-term delivery of bioluminescent substrates. Pump-assisted d-luciferin delivery enabled BLI for ⩾ 7 days from a variety of luciferase reporters. Pumps allowed direct repetitive imaging at < 5-minute intervals of the pharmacodynamics of proteasome- and IKK-inhibiting drugs in mice bearing tumors stably expressing ubiquitin-firefly luciferase or IκBα-firefly luciferase fusion reporters. Circadian oscillations in the olfactory bulbs of transgenic rats expressing firefly luciferase under the control of the period1 promoter also were temporally resolved over the course of several days. We conclude that implanted pumps provide reliable, prolonged substrate delivery for high temporal resolution BLI, traversing complications of repetitive substrate injections.
Radiolabeled Anti-Claudin 4 and Anti-Prostate Stem Cell Antigen: Initial Imaging in Experimental Models of Pancreatic Cancer
Authors: Foss Catherine A. , Fox James J. , Feldmann Georg , Maitra Anirban , Iacobuzio-Donohue Christine , Kern Scott E. , Hruban Ralph , Pomper Martin G.
Published: March 2018

Global expression profiling of pancreatic cancers has identified two cell surface molecules, claudin 4 and prostate stem cell antigen (PSCA), as being overexpressed in the vast majority of cases. Two antibodies, anti-claudin 4 and anti-PSCA, were radiolabeled with iodine 125 (125I) for imaging pancreatic cancer xenografts in mice using gamma scintigraphy and single-photon emission computed tomography-computed tomography (SPECT-CT). Immunofluorescence staining of intact and permeabilized Colo357 human pancreatic cancer cells showed strong extracellular staining by both anti-PSCA and anti-claudin 4. Biodistribution studies in claudin 4 and PSCA-expressing Colo357 and PANC-1 subcutaneous xenograft models in mice showed that [125I]anti-claudin 4 tumor to muscle ratio uptake was 4.3 in Colo357 at 6 days postinjection and 6.3 in PANC-1 xenografts at 4 days postinjection. Biodistribution of [125I]anti-PSCA showed tumor to muscle ratio uptake of 4.9 in Colo357 at 6 days postinjection. Planar gamma scintigraphic imaging in Colo357 xenograft-bearing mice showed clear tumor uptake of [125I]anti-claudin 4 by 24 hours postinjection and by 48 hours postinjection for [125I]anti-PSCA. SPECT-CT imaging with [125I]anti-claudin 4 and [125I]anti-PSCA in an L3.6PL orthotopic xenograft model showed strong tumor and spleen uptake at 5 days postinjection. Both anti-claudin 4 and anti-PSCA demonstrate promise as radiodiagnostic and possibly radiotherapeutic agents for human pancreatic cancers.
Real-Time Multichannel Imaging Framework for Endoscopy, Catheters, and Fixed Geometry Intraoperative Systems
Authors: Sheth Rahul A. , Upadhyay Rabi , Weissleder Ralph , Mahmood Umar
Published: March 2018

To address the need for a clinically applicable intravital optical imaging system, we developed a new hardware and software framework. We demonstrate its utility by applying it to an endoscope-based white light and fluorescent imaging system. The capabilities include acquisition and visualization algorithms that perform registration, segmentation, and histogram-based autoexposure of two imaging channels (full-spectrum white light and near-infrared fluorescence), all in real time. Data are processed and saved as 12-bit files, matching the standards of clinical imaging. Dynamic range is further improved by the evaluation of flux as a quantitative parameter. The above features are demonstrated in a series of in vitro experiments, and the in vivo application is shown with the visualization of fluorescent-labeled vasculature of a mouse peritoneum. The approach may be applied to diverse systems, including handheld devices, fixed geometry intraoperative devices, catheter-based imaging, and multimodal systems.