Novel regulations of the angiotensin II receptor type 1 by calmodulin.

The angiotensin II receptor type 1 (AT1R) mediates many Ca2+-dependent actions of angiotensin II (AngII). Calmodulin (CaM) is a key transducer of Ca2+ signals in cells. Two locations on the receptor's submembrane domains (SMD) 3 and 4 are known to interact with CaM. However, the binding sites for CaM, biochemical properties of the interactions, and their functional impact are not fully understood. Using a FRET-based screening method, we identified a new binding site for CaM on SMD2 (a.a. 125-141), in addition to SMD3 and the juxtamembranous region of SMD4 (SMD4JM, a.a., 309-327). Simultaneous measurements of CaM binding and free Ca2+ show that the interactions are Ca2+-dependent, with disparate Kd and EC50(Ca2+) values within the physiological range of cytoplasmic Ca2+. Full interaction between CaM and SMD3 requires the entire domain (a.a. 215-242) and has an EC50(Ca2+) value in the range of resting cytoplasmic Ca2+, suggesting AT1R-CaM interaction can occur in resting conditions in cells. AngII induces robust ERK1/2 phosphorylation in primary vascular smooth muscle cells. This effect is suppressed by AT1R inhibitor losartan and virtually abolished by CaM antagonist W-7. AngII-induced ERK1/2 phosphorylation is suppressed in cells expressing mutant AT1R with reduced CaM binding at each identified binding domain. AngII triggers transient Ca2+ signals in cells expressing wild-type AT1R. These signals are reduced in cells expressing mutant AT1R with reduced CaM binding at SMD3 or SMD4JM, but are very slow-rising, low amplitude signal in cells expressing AT1R with reduced CaM binding at SMD2. The data indicate that CaM interactions with AT1R can occur at various domains, with different affinities, at different physiological Ca2+ levels, and are important for AT1R-mediated signaling.

A usability study of patient-friendly terminology in an EMR system.

Misunderstandings due to terminology differences between health care providers and consumers may cause communication problems and adversely affect consumer access to health information, resulting in poor satisfaction for patients and providers. To investigate the usage patterns of consumer health vocabulary and evaluate controlled terminologies used in electronic medical records, we conducted a usability study of patient-friendly terms used in an ambulatory electronic medical record (EMR) and associated patient web portal. After identifying 340 unique diagnosis term/patient-friendly term pairs, we mapped the term pairs determined by UMLS to be pairs of synonyms, near-synonyms, or closely-related terms to the keywords of search queries extracted from a consumer health information web portal to learn the comparative frequency of use of members of each pair by consumers. We found out that use of patient-friendly terms could help to bridge the language gap between providers and consumers but not always. In some cases the professional diagnosis terms were used more frequently than their patient-friendly counterparts, typically in cases where the professional terms were more simple or common than the patient-friendly terms.

A presentation system for just-in-time learning in radiology.

There is growing interest in bringing medical educational materials to the point of care. We sought to develop a system for just-in-time learning in radiology. A database of 34 learning modules was derived from previously published journal articles. Learning objectives were specified for each module, and multiple-choice test items were created. A web-based system-called TEMPO-was developed to allow radiologists to select and view the learning modules. Web services were used to exchange clinical context information between TEMPO and the simulated radiology work station. Preliminary evaluation was conducted using the System Usability Scale (SUS) questionnaire. TEMPO identified learning modules that were relevant to the age, sex, imaging modality, and body part or organ system of the patient being viewed by the radiologist on the simulated clinical work station. Users expressed a high degree of satisfaction with the system's design and user interface. TEMPO enables just-in-time learning in radiology, and can be extended to create a fully functional learning management system for point-of-care learning in radiology.

Radiologists' preferences for just-in-time learning.

BACKGROUND: Effective learning can occur at the point of care, when opportunities arise to acquire information and apply it to a clinical problem. To assess interest in point-of-care learning, we conducted a survey to explore radiologists' attitudes and preferences regarding the use of just-in-time learning (JITL) in radiology. MATERIALS AND METHODS: Following Institutional Review Board approval, we invited 104 current radiology residents and 86 radiologists in practice to participate in a 12-item Internet-based survey to assess their attitudes toward just-in-time learning. Voluntary participation in the survey was solicited by e-mail; respondents completed the survey on a web-based form. RESULTS: Seventy-nine physicians completed the questionnaire, including 47 radiology residents and 32 radiologists in practice; the overall response rate was 42%. Respondents generally expressed a strong interest for JITL: 96% indicated a willingness to try such a system, and 38% indicated that they definitely would use a JITL system. They expressed a preference for learning interventions of 5-10 min in length. CONCLUSIONS: Current and recent radiology trainees have expressed a strong interest in just-in-time learning. The information from this survey should be useful in pursuing the design of learning interventions and systems for delivering just-in-time learning to radiologists.

PACSPulse: a web-based DICOM network traffic monitor and analysis tool.

PACSPulse, an open-source tool, was developed to identify and analyze the performance bottlenecks of picture archiving and communication systems (PACS). PACSPulse provides a graphical Web interface for straightforward analysis of PACS performance on the basis of data acquired by tracking usage by network, server, workstation, type of traffic, and time of day. The PACS archive logs performance and usage data on image traffic being sent to it from the imaging units and study data requested by users. The performance log is sent via file transfer protocol (FTP) to a separate server for analysis. The data are parsed and sent to a database server connected to a Web server. The Web site is used to depict trends in the performance of the entire system to detect signs of degradation. The system was built entirely of open-source components for the operating system, database, charting tool, and Web server. Performance monitoring is an essential tool for analyzing, understanding, and predicting the performance characteristics of a PACS.

Radtracker: a web-based open-source issue tracking tool.

Radiology departments are besieged with a multitude of information systems, each needing significant technical support. Information systems include the dictation system, the radiology information system (RIS), the picture archiving and communication systems (PACS), and every workstation and acquisition modality along with any dedicated system such as a teleradiology solution or specialized reporting tools. Typical radiology departments have very limited resources available to provide support. The challenges facing technical support are in responding to mission critical applications during a failure, building a knowledge base for each system, and providing clear communication with the users of the system experiencing problems. We have constructed a web-based support method that addresses the 3 main challenges of supporting so many different information systems with a formalized response mechanism. The website allows anyone to easily submit issues by describing the problem and selecting a specific category. Each support person subscribes to categories for which they are qualified. High-priority issues will be sent automatically to the alphanumeric pagers of the support personnel with the description of the problem. Drill down capabilities on the website allow searching of resolved and unresolved problems. Automatic emails are sent out to the person submitting the problem every time an action is taken to keep them in a closed loop. This tool pools the limited resources of the department and formalizes response mechanism to provide optimal support to the users.