Using Surveillance With Near-Real-Time Alerts During a Cluster of Overdoses From Fentanyl-Contaminated Crack Cocaine, Connecticut, June 2019

In 2019, Connecticut launched an opioid overdose-monitoring program to provide rapid intervention and limit opioid overdose-related harms. The Connecticut Statewide Opioid Response Directive (SWORD)-a collaboration among the Connecticut State Department of Public Health, Connecticut Poison Control Center (CPCC), emergency medical services (EMS), New England High Intensity Drug Trafficking Area (HIDTA), and local harm reduction groups-required EMS providers to call in all suspected opioid overdoses to the CPCC. A centralized data collection system and the HIDTA overdose mapping tool were used to identify outbreaks and direct interventions. We describe the successful identification of a cluster of fentanyl-contaminated crack cocaine overdoses leading to a rapid public health response. On June 1, 2019, paramedics called in to the CPCC 2 people with suspected opioid overdose who reported exclusive use of crack cocaine after being resuscitated with naloxone. When CPCC specialists in poison information followed up on the patients' status with the emergency department, they learned of 2 similar cases, raising suspicion that a batch of crack cocaine was mixed with an opioid, possibly fentanyl. The overdose mapping tool pinpointed the overdose nexus to a neighborhood in Hartford, Connecticut; the CPCC supervisor alerted the Connecticut State Department of Public Health, which in turn notified local health departments, public safety officials, and harm reduction groups. Harm reduction groups distributed fentanyl test strips and naloxone to crack cocaine users and warned them of the dangers of using alone. The outbreak lasted 5 days and tallied at least 22 overdoses, including 6 deaths. SWORD's near-real-time EMS reporting combined with the overdose mapping tool enabled rapid recognition of this overdose cluster, and the public health response likely prevented additional overdoses and loss of life.

A review on blockchain applications in the agri-food sector

BACKGROUND

Food security can benefit from the technology's transparency, relatively low transaction costs and instantaneous applications. A blockchain is a distributed database of records in the form of encrypted blocks, or a public ledger of all transactions or digital events that have been executed and shared among participating parties and can be verified at any time in the future. Generally, the robust and decentralized functionality of the blockchain is used for global financial systems, but it can easily be expanded to contracts and operations such as tracking of the global supply chain. In the precision agriculture context, Information and Communications Technology can be further implemented with a blockchain infrastructure to enable new farm systems and e-agriculture schemes.

RESULTS

The purpose of this review is to show a panorama of the scientific studies (enriched by a terms mapping analysis) on the use of blockchain in the agri-food sector, from both an entirely computational and an applicative point of view. As evidenced by the network analysis, the reviewed studies mainly focused on software aspects (e.g. the architecture and smart contracts). However, some aspects regarding the different blockchain knots (computers always connected to the blockchain network) having the role to store and distribute an updated copy of each block in a food supply-chain, result of crucial importance.

CONCLUSION

These technologies appear very promising and rich of great potential showing a good flexibility for applications in several sectors but still immature and hard to apply due to their complexity. © 2019 Society of Chemical Industry.

"Real-Time" Monitoring of Under-Five Mortality: A Vision Tempered by Reality

Jennifer Bryce and the RMM Working Group describe the origin and rationale of the Real-Time Monitoring of Under-Five Mortality Collection.

Real-time gesture interface based on event-driven processing from stereo silicon retinas

We propose a real-time hand gesture interface based on combining a stereo pair of biologically inspired event-based dynamic vision sensor (DVS) silicon retinas with neuromorphic event-driven postprocessing. Compared with conventional vision or 3-D sensors, the use of DVSs, which output asynchronous and sparse events in response to motion, eliminates the need to extract movements from sequences of video frames, and allows significantly faster and more energy-efficient processing. In addition, the rate of input events depends on the observed movements, and thus provides an additional cue for solving the gesture spotting problem, i.e., finding the onsets and offsets of gestures. We propose a postprocessing framework based on spiking neural networks that can process the events received from the DVSs in real time, and provides an architecture for future implementation in neuromorphic hardware devices. The motion trajectories of moving hands are detected by spatiotemporally correlating the stereoscopically verged asynchronous events from the DVSs by using leaky integrate-and-fire (LIF) neurons. Adaptive thresholds of the LIF neurons achieve the segmentation of trajectories, which are then translated into discrete and finite feature vectors. The feature vectors are classified with hidden Markov models, using a separate Gaussian mixture model for spotting irrelevant transition gestures. The disparity information from stereovision is used to adapt LIF neuron parameters to achieve recognition invariant of the distance of the user to the sensor, and also helps to filter out movements in the background of the user. Exploiting the high dynamic range of DVSs, furthermore, allows gesture recognition over a 60-dB range of scene illuminance. The system achieves recognition rates well over 90% under a variety of variable conditions with static and dynamic backgrounds with naïve users.

A randomized trial of real-time automated clinical deterioration alerts sent to a rapid response team

BACKGROUND

Episodes of patient deterioration on hospital units are expected to increasingly contribute to morbidity and healthcare costs.

OBJECTIVE

To determine if real-time alerts sent to the rapid response team (RRT) improved patient care.

DESIGN

Randomized, controlled trial.

SETTING

Eight medicine units (Barnes-Jewish Hospital).

PATIENTS

Five hundred seventy-one patients.

INTERVENTION

Real-time alerts generated by a validated deterioration algorithm were sent real-time to the RRT (intervention) or hidden (control).

MEASUREMENTS

Intensive care unit (ICU) transfer, hospital mortality, hospital duration.

RESULTS

ICU transfer (17.8% vs 18.2%; odds ratio: 0.972; 95% confidence interval [CI]: 0.635-1.490) and hospital mortality (7.3% vs 7.7%; odds ratio: 0.947; 95% CI: 0.509-1.764) were similar for the intervention and control groups. The number of patients requiring transfer to a nursing home or long-term acute care hospital was similar for patients in the intervention and control groups (26.9% vs 26.3%; odds ratio: 1.032; 95% CI: 0.712-1.495). Hospital duration (8.4 ± 9.5 days vs 9.4 ± 11.1 days; P = 0.038) was statistically shorter for the intervention group. The number of RRT calls initiated by the primary care team was similar for the intervention and control groups (19.9% vs 16.5%; odds ratio: 1.260; 95% CI: 0.823-1.931).

CONCLUSIONS

Real-time alerts sent to the RRT did not reduce ICU transfers, hospital mortality, or the need for subsequent long term care. However, hospital length of stay was modestly reduced.

A trial of a real-time alert for clinical deterioration in patients hospitalized on general medical wards

BACKGROUND

With limited numbers of intensive care unit (ICU) beds available, increasing patient acuity is expected to contribute to episodes of inpatient deterioration on general wards.

OBJECTIVE

To prospectively validate a predictive algorithm for clinical deterioration in general-medical ward patients, and to conduct a trial of real-time alerts based on this algorithm.

DESIGN

Randomized, controlled crossover study.

SETTING/PATIENTS

Academic center with patients hospitalized on 8 general wards between July 2007 and December 2011.

INTERVENTIONS

Real-time alerts were generated by an algorithm designed to predict the need for ICU transfer using electronically available data. The alerts were sent by text page to the nurse manager on intervention wards.

MEASUREMENTS

Intensive care unit transfer, hospital mortality, and hospital length of stay.

RESULTS

Patients meeting the alert threshold were at nearly 5.3-fold greater risk of ICU transfer (95% confidence interval [CI]: 4.6-6.0) than those not satisfying the alert threshold (358 of 2353 [15.2%] vs 512 of 17678 [2.9%]). Patients with alerts were at 8.9-fold greater risk of death (95% CI: 7.4-10.7) than those without alerts (244 of 2353 [10.4%] vs 206 of 17678 [1.2%]). Among patients identified by the early warning system, there were no differences in the proportion of patients who were transferred to the ICU or who died in the intervention group as compared with the control group.

CONCLUSIONS

Real-time alerts were highly specific for clinical deterioration resulting in ICU transfer and death, and were associated with longer hospital length of stay. However, an intervention notifying a nurse of the risk did not result in improvement in these outcomes.

Development and evaluation of a novel, real time mobile telesonography system in management of patients with abdominal trauma: study protocol

BACKGROUND

Despite the use of e-FAST in management of patients with abdominal trauma, its utility in prehospital setting is not widely adopted. The goal of this study is to develop a novel portable telesonography (TS) system and evaluate the comparability of the quality of images obtained via this system among healthy volunteers who undergo e-FAST abdominal examination in a moving ambulance and at the ED. We hypothesize that: (1) real-time ultrasound images of acute trauma patients in the pre-hospital setting can be obtained and transmitted to the ED via the novel TS system; and (2) Ultrasound images transmitted to the hospital from the real-time TS system will be comparable in quality to those obtained in the ED.

METHODS

Study participants are three healthy volunteers (one each with normal, overweight and obese BMI category). The ultrasound images will be obtained by two ultrasound-trained physicians The TS is a portable sonogram (by Sonosite) interfaced with a portable broadcast unit (by Live-U). Two UTPs will conduct e-FAST examinations on healthy volunteers in moving ambulances and transmit the images via cellular network to the hospital server, where they are stored. Upon arrival in the ED, the same UTPs will obtain another set of images from the volunteers, which are then compared to those obtained in the moving ambulances by another set of blinded UTPs (evaluators) using a validated image quality scale, the Questionnaire for User Interaction Satisfaction (QUIS).

DISCUSSION

Findings from this study will provide needed data on the validity of the novel TS in transmitting live images from moving ambulances to images obtained in the ED thus providing opportunity to facilitate medical care of a patient located in a remote or austere setting.

Office computer systems for the dental office

The role of computers in dental practice has dramatically changed over the past 30 years. We have witnessed the progression from administrative roles to complete integration leading to chartless offices. As the dental community gradually adopts this contemporary development, the move to electronic health records is imminent because of upcoming changes in the health care system. The past, present, and future of dental office computer systems is explored in this article. An understanding of the benefits and current challenges of contemporary dental practice software is also reviewed.

[Facing the challenges of ubiquitous computing in the health care sector]

The steady progress of microelectronics, communications and information technology will enable the realisation of the vision for "ubiquitous computing" where the Internet extends into the real world embracing everyday objects. The necessary technical basis is already in place. Due to their diminishing size, constantly falling price and declining energy consumption, processors, communications modules and sensors are being increasingly integrated into everyday objects today. This development is opening up huge opportunities for both the economy and individuals. In the present paper we discuss possible applications, but also technical, social and economic barriers to a wide-spread use of ubiquitous computing in the health care sector.

Healthy living with persuasive technologies: framework, issues, and challenges

While our Y2K worries about old computers "retiring" at midnight captured the television and news media attention, a more significant "old age" phenomenon snuck onto the scene with hardly a headline: the dawn of the age of the aged. (1) The over burdened health care system will face a worldwide wave of retirees who will live longer, cost more to treat, and demand new goods and services to help them stay healthy, active, and independent. Research in persuasive technologies and the associated usage of a computing system, device, or application intentionally designed to change a person's attitude or behavior in a predetermined way is showing the potential to assist in improving healthy living, reduce the costs on the health care system, and allow the aged to maintain a more independent life. This article gives a deeper insight into the evolution of persuasive technologies and presents a framework that can guide a researcher or practitioner in comprehending more effectively the work being done in this novel research field. It also provides categories of domains within health care in which these technologies are used and surveys exemplars from published literature. The article's goal is to provide greater understanding by addressing the challenges that lie ahead for all key stakeholders that design and/or use persuasive technologies in health care.

The future as I see it

Predicting the future is always chancy, but when a young practitioner begins a career in dentistry, it is worthwhile to have some well-reasoned expectations. The critical dimensions in the next several decades in dentistry will include technology, marketing, and society.

Active ageing: independence through technology assisted health optimisation

The potential doubling in the percentage of the elderly within the populations of Europe and beyond over the next decades has focused informatics research on the development Assistive Technologies and Smart Homes. However its concentration on creating a supportive home environment also has the potential for makings its users over dependent on its facilities and as a result trapped within it. This paper outlines an approach that extends the smart homes concept out into the wider community to create a smart environment that not only maintains contact with all their home-based services, but also expands these to include other facilities needed to assist them whilst on the move. This involves the convergence of physiological monitoring, communications and computing with leading-edge textile technologies, which uses a multi-layered, multi-functional clothing system as a mobile and extended variant of a smart home IP hub. In addition to variable functionality capabilities of the clothing layers in terms of thermal, shock-absorbent and other characteristics, wireless IP connectivity is provided between layers with external links typically being WiFi enabled. Health optimisation is provided by on-going lifestyle guidance/action feedback based on auto-diagnostic analysis.

From documents on paper to electronic medical records

This paper describes the creation process of an electronic medical records (EMR) application in the Juan Canalejo University Hospital Complex (CHUJC). From the knowledge acquired through the observation of the traditional processes of managing the Patients medical records on paper a tool was developed which in principle was thought of to classify electronic documents associated to a patient and to which different functions of medical work have been subsequently added: visualizing clinical documents of patients, creation of new documents and following the development of patients.

Review of ICT-based services for identified unmet needs in people with dementia

Some of the needs that people with dementia and their informal carers currently perceive as insufficiently met by regular care and support services might be alleviated, or even be met, using modern Information and Communication Technology (ICT). The study described in this paper was designed to provide an insight into the state of the art in ICT solutions that could contribute to meet the most frequently mentioned unmet needs by people with dementia and their informal carers. These needs can be summarized as (1) the need for general and personalized information; (2) the need for support with regard to symptoms of dementia; (3) the need for social contact and company; and (4) the need for health monitoring and perceived safety. Databases that were searched include: PubMed, Cinahl, Psychinfo, Google (Scholar), INSPEC and IEEE. In total 22 websites and 46 publications were included that satisfied the following criteria: the article reports on people with dementia and/or their informal carers and discusses an ICT-device that has been tested within the target group and has proven to be helpful. Within the first need area 18 relevant websites and three studies were included; within the second need area 4 websites and 20 publications were included. Within the third and fourth need area 11 and 12 publications were included respectively. Most articles reported on uncontrolled studies. It is concluded that the informational websites offer helpful information for carers but seem less attuned to the person with dementia and do not offer personalized information. ICT solutions aimed at compensating for disabilities, such as memory problems and daily activities demonstrate that people with mild to moderate dementia are capable of handling simple electronic equipment and can benefit from it in terms of more confidence and enhanced positive effect. Instrumental ICT-support for coping with behavioral and psychological changes in dementia is relatively disregarded as yet, while support for social contact can be effectively realized through, for example, simplified (mobile) phones or videophones or (entertainment) robots. GPS technology and monitoring systems are proven to result in enhanced feelings of safety and less fear and anxiety. Though these results are promising, more controlled studies in which the developed ICT solutions are tested in real life situations are needed before implementing them in the care for people with dementia. It is recommended that future studies also focus on the integration of the current techniques and solutions.

[Current trends and prospects of development of biofeedback hardware]

Current trends in the development of biofeedback hardware are considered. At present, computer-based systems hold the leading positions on the market of biofeedback devices. Development of computer technologies affects the design of biofeedback hardware. One of the trends in the evolution of biofeedback devices is the simplification of electronic circuitry, while an increasing role in the signal processing is allocated to a computer. Modern wireless technologies, such as Bluetooth and ZigBee, hold much promise for the development of biofeedback hardware.

Patient-reported outcomes measurement and management with innovative methodologies and technologies

Successful integration of modern psychometrics and advanced informatics in patient-reported outcomes (PRO) measurement and management can potentially maximize the value of health outcomes research and optimize the delivery of quality patient care. Unlike the traditional labor-intensive paper-and-pencil data collection method, item response theory-based computerized adaptive testing methodologies coupled with novel technologies provide an integrated environment to collect, analyze and present ready-to-use PRO data for informed and shared decision-making. This article describes the needs, challenges and solutions for accurate, efficient and cost-effective PRO data acquisition and dissemination means in order to provide critical and timely PRO information necessary to actively support and enhance routine patient care in busy clinical settings.

Intraoperative neurophysiological monitoring technology: recent advances and evolving uses

Intraoperative neurophysiological monitoring has evolved over the last 25 years to become an important component of many types of orthopedic and neurosurgical procedures. From its foundations in VIII cranial nerve surgeries and scoliosis corrections surgeries, intraoperative neurophysiological monitoring has expanded to incorporate nearly all spine procedures and many involving the brain and brainstem. Fundamental to this growth in the use of intraoperative neurophysiological monitoring has been the development of the technology used to perform the neurophysiological tests. Advancements in electronics and computer technology have resulted in significant improvements in the capacity, ease of use, quality and reliability of the equipment as well as the quality of and control over the acquired data. These technological advancements have resulted in remarkable improvements in not only the quality and availability of intraoperative neurophysiological monitoring, but also, as a consequence, patient care, and have arguably propelled the expansion of the use that intraoperative neurophysiological monitoring has seen over the last 10 years.

Quantitative nested real-time PCR assay for assessing the clinical course of tuberculous meningitis

Although the "gold standard" for diagnosis of tuberculous meningitis (TBM) is bacterial isolation of Mycobacterium tuberculosis (M. Tb), there are still several complex issues. Recently, in the diagnosis of TBM, the detection of M. Tb DNA in cerebrospinal fluid (CSF) samples using PCR has been widely performed as more rapid, sensitive, and specific diagnostic method. Based on Taq Man(R) PCR, the authors developed a novel technique of internally controlled quantitative nested real-time (QNRT) PCR assay that provided a prominent improvement in detection sensitivity and quantification. Total 43 CSF samples from 8 serial patients with suspected TBM were analyzed. The CSF samples were collected before and during standard anti-tuberculosis treatments (ATT). The QNRT-PCR assay revealed positive results for 24 out of 43 serial CSF samples (55.8%) collected during the treatment course of ATT. Moreover, the bacterial cell (BC) numbers of M. Tb analyzed by the QNRT-PCR assay decreased gradually, correlating with the improvements of the patient's clinical conditions. Since the QNRT-PCR assay provides the ability to calculate a numerical value for the initial BC numbers of M. Tb in CSF samples, this method is an extremely useful and advanced technique for use in assessing the clinical course of TBM.

Improving general practice computer systems for patient safety: qualitative study of key stakeholders

OBJECTIVE

The authors sought to identify ways in which the use of general practice computer systems could be improved to enhance safety in primary care.

DESIGN

Qualitative study using semistructured interviews.

PARTICIPANTS

Thirty one participants, representing a broad range of relevant disciplines and interest groups. Participants included clinicians, computer system and drug database suppliers, academics with interests in health informatics and members of governmental, professional and patient representative bodies.

SETTING

UK.

RESULTS

Participants identified deficiencies in current systems that pose serious threats to patient safety. To bring about improvements, providers need to supply clinicians with safe, accurate and accessible information for decision support; be aware of the importance of human ergonomics in the design of hazard alerts; consider the value of audit trails and develop mechanisms to allow for the accurate transfer of information between clinical computer systems. These improvements in computer systems will be most likely to occur if mandated through regulations. Individual practices are in need of improved education and training which focuses, in particular, on providing support with recording data accurately and using call, recall and reminders effectively.

CONCLUSION

There are significant opportunities for improving the safety of general practice computer systems. Priorities include improving the knowledge base for clinical decision support, paying greater attention to human ergonomics in system design, improved staff training and the introduction of new regulations mandating system suppliers to satisfy essential safety requirements.

Electronic Medical Records for a Rural Family Practice: A Case Study In Systems Development

In this paper, we describe the planning, development, and overall impact of Electronic Medical Records (EMRs) on Dryden Family Medicine (DFM), a rural family practice in Dryden, New York. The EMR system was installed in July, 2003, and the full conversion to the new system was accomplished in three phases. Significant efficiency gains were achieved in billing, prescription ordering, and other routine processes. Protocols were developed to enhance quality management, preventive medicine, and disease management. Job responsibilities changed and expanded for all members of the practice and coding issues became paramount. Practice revenue increased by about 20 percent and average "case-mix" increased by 10 percent in the second year following the implementation of EMRs due to improved billing documentation. We focus on the implementation process, the lessons learned, the obstacles encountered, and the successes achieved by one rural family practice.

Revolutions and shifting paradigms in human factors & ergonomics

The "Revolution in Information Technology" has spawned a series of transformational revolutions in the nature and practice of human factors and ergonomics (HFE). "Generation 1" HFE evolved with a focus on adapting equipment, workplace and tasks to human capabilities and limitations. Generation 2, focused on cognitive systems integration, arose in response to the need to manage automation and dynamic function allocation. Generation 3 is focused on symbiotic technologies that can amplify human physical and cognitive capabilities. Generation 4 is emergent and is focused on biological enhancement of physical or cognitive capabilities. The shift from HFE Generations 1 and 2 to Generations 3 and 4 profoundly alters accepted boundary constraints on the adaptability of humans in complex systems design. Furthermore, it has opened an ethical divide between those that see cognitive and physical enhancement as a great benefit to society and those who perceive this as tampering with the fundamentals of human nature.

The future of real-time cardiac magnetic resonance imaging

Dynamic changes in cardiac structure and function are usually examined by real-time imaging techniques such as angiography or echocardiography. MRI has many advantages compared with these established cardiac imaging modalities. However, system hardware and software limitations have limited cardiac MRI to gated acquisitions that are lengthy and often result in failed acquisitions and examinations. Recently, MRI has evolved into a technique capable of imaging dynamic processes in real time. Improvements in hardware, pulse sequences, and image reconstruction algorithms have enabled real-time cardiac MRI with high spatial resolution, high temporal resolution, and various types of image contrast without requiring cardiac gating or breath-holding. This article provides an overview of current capability and highlights key technical and clinical advances. The future prospects of real-time cardiac MRI will depend on 1) the development of techniques that further improve signal to noise ratio, contrast, spatial resolution, and temporal resolution, without introducing artifacts; 2) the development of software infrastructure that facilitates rapid interactive examination; and 3) the development and validation of several new clinical assessments.

Evolving telemedicine/ehealth technology

This paper describes emerging technologies to support a rapidly changing and expanding scope of telemedicine/telehealth applications. Of primary interest here are wireless systems, emerging broadband, nanotechnology, intelligent agent applications, and grid computing. More specifically, the paper describes the changes underway in wireless designs aimed at enhancing security; some of the current work involving the development of nanotechnology applications and research into the use of intelligent agents/artificial intelligence technology to establish what are termed "Knowbots"; and a sampling of the use of Web services, such as grid computing capabilities, to support medical applications. In addition, the expansion of these technologies and the need for cost containment to sustain future health care for an increasingly mobile and aging population is discussed.

Toward technical interoperability in telemedicine

For telemedicine to realize the vision of anywhere, anytime access to care, the question of how to create a fully interoperable technical infrastructure must be addressed. After briefly discussing how "technical interoperability" compares with other types of interoperability being addressed in the telemedicine community today, this paper describes reasons for pursuing technical interoperability, presents a proposed framework for realizing technical interoperability, identifies key issues that will need to be addressed if technical interoperability is to be achieved, and suggests a course of action that the telemedicine community might follow to accomplish this goal.

[Design of software and hardware complex of automated systems for the management of the State Sanitary and Epidemiological Surveillance]

A new information system (IS) - the software and hardware complex for controlling the state sanitary-and-epidemiological inspection (SSEI) was created. The system represents the aggregate of automated working places of RF MD chief state sanitary physician arid specialists from the department of state sanitary-and-epidemiological inspection of the Main Military Medical Headquarters. They interact through communications with working places of specialists from SSEI Main Center, chief state sanitary physicians from the Armed Forces, military districts (fleets) and RFAF CSSEI. The special software provides automation of the following technological processes: operative sanitary-and epidemiological and epidemiological monitoring; the epidemiological analysis of infectious diseases; the evaluation of quality and efficiency of sanitary-and epidemiological work. At present the complex works in the regime of experimental exploitation when the adjustment of communications and special software is performed.

The impact of information technology on haemophilia care

The past decade has seen an explosion in the use of computers, data programs, hand-held electronic devices and the Internet. How these advances impact on haemophilia management both now and in the future are discussed from the perspective of haemophilia registries, Internet-based electronic haemophilia treatment records, and the potential for haemophilia telehealth.

Real-time PCR

The development of instruments that allow real-time monitoring of fluorescence within PCR reaction vessels is a significant advance in clinical bacteriology. The technology is very flexible, and many alternative instruments and fluorescent probe systems are currently available. Real-time PCR assays can be completed very rapidly, because no manipulations are required after amplification. Identification of amplification products by probe detection in real time is highly accurate compared with size analysis on gels. Analysis of the progress of the reaction allows accurate quantification of the target sequence over a very wide dynamic range, provided suitable standards are available. Finally, probe melting analysis can detect sequence variants including single base mutations.

In our hands? The future of health care technology

Use improvements in data accuracy and nursing productivity to enhance your quality of care.

The Use of Spin-Labeled Ligands as Biophysical Probes to Report Real-Time Endocytosis of G Protein-Coupled Receptors in Living Cells

Recycling and degradation of plasma membrane receptors and transporters are fundamental mechanisms for regulating cell signaling and metabolic processes. For many membrane proteins, endocytosis reduces the number of molecules available for transport or signal transduction, providing an attenuation response. Fluorescent reporters attached to either the receptor or ligand have been used to monitor the trafficking of internalization; however, these approaches provide poor resolution for the early endocytic response. Here, we describe the use of a spin-labeled ligand for a heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptor for measuring the kinetics of endocytosis in real time. Included are protocols for designing a nitroxide-labeled ligand and measuring receptor endocytosis in live cells using electron paramagnetic resonance (EPR) spectroscopy. Methods for the evaluation of the receptor binding and activation properties of modified ligands and the generation of a cell line stably expressing high receptor levels are also provided.

Virtual Reality Neurosurgery: A Simulator Blueprint

OBJECTIVE

This article details preliminary studies undertaken to integrate the most relevant advancements across multiple disciplines in an effort to construct a highly realistic neurosurgical simulator based on a distributed computer architecture. Techniques based on modified computational modeling paradigms incorporating finite element analysis are presented, as are current and projected efforts directed toward the implementation of a novel bidirectional haptic device.

METHODS

Patient-specific data derived from noninvasive magnetic resonance imaging sequences are used to construct a computational model of the surgical region of interest. Magnetic resonance images of the brain may be coregistered with those obtained from magnetic resonance angiography, magnetic resonance venography, and diffusion tensor imaging to formulate models of varying anatomic complexity.

RESULTS

The majority of the computational burden is encountered in the presimulation reduction of the computational model and allows realization of the required threshold rates for the accurate and realistic representation of real-time visual animations.

CONCLUSION

Intracranial neurosurgical procedures offer an ideal testing site for the development of a totally immersive virtual reality surgical simulator when compared with the simulations required in other surgical subspecialties. The material properties of the brain as well as the typically small volumes of tissue exposed in the surgical field, coupled with techniques and strategies to minimize computational demands, provide unique opportunities for the development of such a simulator. Incorporation of real-time haptic and visual feedback is approached here and likely will be accomplished soon.

Teleradiology in orthopaedics

Teleradiology is a means of electronically transmitting radiographic image files from one location to another. Technologic advances in digital imaging, telecommunications, digital storage, and viewing technologies have made teleradiology readily available and reasonably affordable. The five components of a teleradiology system include: a sending station, a transmission network, a storage device, a viewing station and, a software package. The advantage of teleradiology is the mobility of digital images. In contrast to plain radiographs that only can be seen in one location at a time, multiple persons who are at different locations can view digital images simultaneously. When applied to orthopaedic trauma applications, when the consulting orthopaedist is at a remote location from the patient, teleradiology has been shown to improve diagnostic accuracy, disposition planning of patients from emergency departments or outlying hospitals, and planning of surgical procedures. These systems also improve the comfort level of consulting orthopaedic surgeons and potentially limit the risk of litigation for incorrect diagnosis. The quality, convenience, and effectiveness of teleradiology systems should improve as the technologies continue to mature. Having radiographic images available on handheld devices, such as cell phones, is likely to be a reality in the near future.

MRCI: a flexible real-time dynamic clamp system for electrophysiology experiments

We present a real-time simulation system that enables modeled dynamical systems to interact with physical experimental systems, and is specifically aimed towards execution of the dynamic clamp protocol. Model reference current injection (MRCI) operates under Real-Time Linux (RT-Linux or RTL) and provides a simple equation-oriented language for describing dynamical system models. Features include scripting of commands to implement repeatable protocols, the ability to output pre-computed waveforms through any variable or parameter of the model, the means to conduct time measurements and assess the computational performance of the real-time system, and an installation program that installs the software and accompanying device drivers with minimal input from the user. Tested models operate as fast as 30 kHz, with actual maximum rates dependent on model complexity. We present sample models that exhibit the main features of the modeling language. Experiments demonstrate the abilities of the system by creating a hybrid network of real and simulated neurons, and playing a pre-defined synaptic waveform into a synaptic conductance variable. We conclude by introducing a waveform reconstruction technique that is useful for establishing the presence of significant experimental error in implementations of the dynamic clamp protocol.

Implementation of a fast 16-Bit dynamic clamp using LabVIEW-RT

The dynamic-clamp method provides a powerful electrophysiological tool for creating virtual ionic conductances in living cells and studying their influence on membrane potential. Here we describe G-clamp, a new way to implement a dynamic clamp using the real-time version of the Lab-VIEW programming environment together with a Windows host, an embedded microprocessor that runs a real-time operating system and a multifunction data-acquisition board. The software includes descriptions of a fast voltage-dependent sodium conductance, delayed rectifier, M-type and A-type potassium conductances, and a leak conductance. The system can also read synaptic conductance waveforms from preassembled data files. These virtual conductances can be reliably implemented at speeds < or =43 kHz while simultaneously saving two channels of data with 16-bit precision. G-clamp also includes utilities for measuring current-voltage relations, synaptic strength, and synaptic gain. Taking an approach built on a commercially available software/hardware platform has resulted in a system that is easy to assemble and upgrade. In addition, the graphical programming structure of LabVIEW should make it relatively easy for others to adapt G-clamp for new experimental applications.

Development of a real-time RT-PCR assay for the quantification of the most frequentMLL/AF9fusion types resulting from translocation t(9;11)(p22;q23) in acute myeloid leukemia

One strategy to predict clinical outcome in patients with acute myeloid leukemia (AML) is detection of minimal residual disease (MRD) after achievement of hematologic complete remission (CR). We established a real-time RT-PCR assay by use of TaqMan technology for the identification of MRD by quantification of the most frequent fusion transcripts resulting from t(9;11)(p22;q23). To achieve comparable PCR efficiencies between the different PCR assays, primers were chosen to obtain amplicons of nearly identical lengths. MLL/AF9 copy numbers were normalized to the housekeeping gene porphobilinogen deaminase (PBGD). The sensitivity of the assay, as determined at the cellular level, was comparable to that of qualitative single-round RT-PCR. Samples from eight patients with t(9;11)-positive AML were analyzed. At diagnosis and relapse, normalized copy numbers were positive and ranged from 490 to 5,558. Samples from two of seven patients collected at the time of CR became negative, whereas five cases still had positive normalized copy numbers with values between 5 and 5,286. The implications of MRD detection by MLL/AF9 fusion transcript quantification for the clinical management of t(9;11)-positive AML have to be determined in further studies.