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Nursing intranet for communication and knowledge management.

Leveraging on staff's familiarity with the global Internet and the Hospital Information Technology infrastructure, nurses at Singapore General Hospital (SGH) first took the challenge to design and develop an in-house intranet, which serves as a communication network in 1997. This nursing intranet was further enhanced using multi-media technology to develop e-learning modules on nursing specialty, skill-based, and audio slides presentation training. In addition, it also serves as a repository for policies, operational, nursing procedure documents and catalogue of forms, patient instruction pamphlets. Nurses can easily print all these forms and teaching brochures on-line. The nursing intranet offers cost-effective solution for distributing information through virtual network and accessible from over 700 points in SGH, 6 other affiliated medical institutions, and from nurses' homes too.

Communication↗

Binding in short-term visual memory.

The integration of complex information in working memory, and its effect on capacity, shape the limits of conscious cognition. The literature conflicts on whether short-term visual memory represents information as integrated objects. A change-detection paradigm using objects defined by color with location or shape was used to investigate binding in short-term visual memory. Results showed that features from the same dimension compete for capacity, whereas features from different dimensions can be stored in parallel. Binding between these features can occur, but focused attention is required to create and maintain the binding over time, and this integrated format is vulnerable to interference. In the proposed model, working memory capacity is limited both by the independent capacity of simple feature stores and by demands on attention networks that integrate this distributed information into complex but unified thought objects.

Analysis of Variance↗

The microdosimetry of lymphocytes irradiated by alpha-particles.

Although the concept of absorbed dose is commonly used in radiation biology as a parameter for comparing the toxic effect of different levels of radiation on a system, there are situations where the absorbed dose by itself is inadequate, and additional dose distribution information is required to explain the observed biological effects. A good example is the irradiation of cells by alpha-particles. This paper reports the use of internal microdosimetry techniques to reinvestigate the dosimetry to two very similar experiments with apparently contradictory dose-response results. Yields of dicentric chromosome aberrations induced in human blood lymphocytes following in vitro exposure to dissolved americium or plutonium at two separate laboratories produced linear dose-response functions, but the slopes of the best-fit straight lines differed by a factor of 12. Our microdosimetric analysis showed the results of one experiment to be inconsistent with a uniform distribution of activity. It also showed that the difference in slope could be attributed to differences in particulate size and spatial distribution as a result of dissimilarities in procedures used for preparing the actinide solutions.

Alpha Particles↗

e-Consent: The design and implementation of consumer consent mechanisms in an electronic environment.

The effective coordination of health care relies on communication of confidential information about consumers between different health and community care services. However, consumers must be able to give or withhold "e-Consent" to those who wish to access their electronic health information. There are several possible forms for e-Consent. In the general consent model, a patient provides blanket consent for access to his or her information by an organization for all future information requests. Conversely, general denial explicitly denies consent for information to be used in future circumstances, and in each new episode of care, a new consent would be needed to obtain information. In the general consent with specific denial model, a patient attaches specific exclusion conditions to his or her general approval to future accesses. In contrast, in the general denial with explicit consent model, a patient issues a blanket block on all future accesses but allows the inclusion of future use under specified conditions. There also are several alternative functions for an e-Consent system. Consent could be captured as a matter of legal record. E-Consent systems could be more active by prompting clinicians to indicate that they have noted consent conditions before they access a record. Finally, the record of patient consent could be fully active and used as a gatekeeper in a distributed information environment. There probably will need to be some form of data object that is associated with patient information. This e-Consent object (or e-Co) will contain the specific conditions under which the data to which it is attached can be retrieved. Given the complexity of clinical work and the substantial variation we can expect in an individual's desire to make his or her personal medical details available, it is unlikely a "one size fits all" approach to e-Consent will work. Consequently, with a well-chosen consent design, it should be possible to balance the specific need for privacy of some of the population against the desire by others to err on the side of clinical safety, and clinicians desire to minimize the burden that an electronic consent mechanism would impose.

Access to Information↗

Frambu Health Centre: promoting family focused care for disabled children.

During the last 30 years the Frambu Health Centre has evolved from a summer-camp site for children with poliomyelitis to a modern information and treatment Centre for families with disabled members. Since 1976, fortnightly courses have been held for an increasing number of patients with rare, often congenital and/or hereditary disorders (anorectal anomalies, bladder extrophy, congenital heart defects, cystic fibrosis, severe diabetes, hemophilia, hip joint defects, juvenile rheumatoid arthritis, minimal brain dysfunction, muscular dystrophy, phenylketonuria, psychosis/autism, spina bifida, Huntington's chorea, osteogenesis imperfecta, retitinitis pigmentosa, a. o.). This article describes the facilities, operation, financing and staff at Frambu. An outline of the course programme is given. The contents of two research projects carried out at Frambu are described. When families with rare disorders meet for the first time, new perspectives open up. Exchange of experience and feelings, establishing lay organizations, collating and distributing information to professionals and families are some of the important results of the Frambu courses.

Child↗

Information theory analysis of the relationship between primary sequence structure and ligand recognition among a class of facilitated transporters.

Determining how specificity for a given ligand occurs among sequence and structurally related transporters is a fundamental problem in elucidating facilitated transport. It is likely that the specificity of a transporter for a ligand is defined by the primary amino acid sequence, and that different ligand specificities among highly related proteins are associated with variations in the amino acid sequence. To assist studies on the potential relationships between protein structure and ligand specificity, information theory was used to assign a measure that quantitates the importance of amino acid choice at individual sites in protein sequences based upon their variability. The approach allows for the transformation of a collection of multiply aligned sequences into a profile that provides a quantitative assessment of the relative frequencies of chemically similar residues at each site. Profiles generated from particular groups of proteins can be directly compared to profiles generated for other groups. These comparisons allow unique differences in the utilization of amino acids at individual sites to be identified as differences in information distribution. The approach was applied to the problem of identifying sites of the dopamine transporter which may play a role in distinguishing its ligand specificity and function from those of a related population of transporters for amino acid and amino-acid-like ligands. Several sites were identified that appear highly likely to distinguish the dopamine transporter from related proteins. Many of the sites identified were also found to be associated with predicted variations in local secondary and tertiary structure between the two classes of proteins.

Animals↗

Assessment of barriers to utilization of poison centers by Hispanic/Latino populations.

Previous research suggests that Spanish-speaking parents and residents of areas with large Hispanic and Latino populations are likely to underutilize the assistance that is available through poison control centers (PCCs). In order to examine any real and perceived barriers to utilization of the New Jersey Poison Information and Education System (NJPIES), the only poison control center in the state, an intercept survey was conducted with self-identified Hispanics/Latinos at Women, Infant, and Children (WIC) centers and in nearby grocery stores, bus stops, and public laundromats. Only 38% of the study sample (n = 206) had heard of NJPIES. Common ways to have heard of NJPIES included school or church bulletins, family members, and friends. Twenty-three percent knew the NJPIES's toll-free phone number; 23% knew it was available 24 h per day; and 22% knew that Spanish-speaking personnel were available for assistance. Potential barriers to utilization included not knowing the phone number of the poison center, not speaking English, and not knowing if the poison center could offer any help. Respondent-recommended strategies for increasing awareness of NJPIES among Hispanics/Latinos included advertising on TV, and distributing information through school and church bulletins.

Adult↗

The risk of enteric diseases in young children and environmental indicators in sentinel areas of Mexico City.

The overall objective of this study is to promote the development of environmental health indicators in Mexico City. Specific examples focused on water quality, household characteristics e.g., sanitation and risk of enteric diseases. A geographic information system (GIS) was used in order to identify eligible wells and their surrounding homesteads (0.5 km around each well). A pilot study was conducted during the rainy season (1999), and a total of 1, 250 eligible households were visited on a random sample basis; only those having children under 5 years of age were interviewed. Data on diarrheal disease (i.e. occurrence in the previous two weeks) were obtained from 950 children, and their guardians provided information on their water supply, sanitation and socioeconomic variables. A total of 320 water samples were obtained from 40 wells, and tested for Total coliforms (TC/100 ml), Fecal coliforms (FC/100 ml). Escherichia coli (EC) and Fecal streptococci (FS). Bacterial indicators were detected in 40% of the wells in the western zone and in 32% of the southern zone (p = 0.01). The rate of diarrheal diseases was higher for children from the southern areas than in the west (OR = 1.7 and 95% CI: 0.99, 2.86). The final analysis showed a higher risk of diarrhea in children from rented homes than those living in owned dwellings (OR = 1.7 and 95% Cl: 1.04, 2.77): the risk was also highest for children living in houses with poor sanitation facilities (e.g., latrine) than those connected to a sewerage (OR = 1.7 and 95% Cl: 1.00, 2.93). Children from households perceiving unpleasant taste of water showed a higher risk than those without complaints (OR = 2.2 and 95% Cl: 1.28, 3.75). Linkages between environmental factors and health risk were created from spatially distributed information, and the proposed environmental health indicator (EHI) summarized the most significant predictors of diarrheal diseases. This baseline information may contribute to further environmental health investigation and policy making analysis.

Child Welfare↗

Development of an MR-compatible gamma probe for combined MR/RI guided surgery.

We have developed and tested an MR-compatible gamma probe to simultaneously obtain anatomical information and functional information during surgery. The probe consists of a probe head, an optical fibre bundle and a photo-multiplier tube (PMT). The NaI(T1) scintillator contained in the probe head is connected to a 7 m optical fibre bundle that transfers the scintillation photons produced in the NaI(T1) to an area of low magnetic field or out of the MR-scanner's magnetic shielded room. Although the light loss due to the optical fibre bundle was more than 90%, the photo-peak of the gamma for Co-57 (122 keV) could be observed. The point spread function was 4.5 mm full width at half maximum (FWHM) at 5 mm from the collimator surface for 122 keV gamma photons. Furthermore, there was no sensitivity change outside the MR-scanner, inside the MR-scanner without scanning and inside the MR-scanner with scanning. The probe produced a small artefact on the phantom image of the MR-scanner due to the susceptibility difference of the alloy used for the collimator and the shield. However, the artefact was only limited to area surrounding the probe. These results indicate that the developed MR-compatible gamma probe will make it possible to realize the combined MR/RI guided surgery that provides surgeons with anatomical and RI distribution information simultaneously.

Equipment Design↗

Information-theoretic latent distribution modeling: distinguishing discrete and continuous latent variable models.

Distinguishing between discrete and continuous latent variable distributions has become increasingly important in numerous domains of behavioral science. Here, the authors explore an information-theoretic approach to latent distribution modeling, in which the ability of latent distribution models to represent statistical information in observed data is emphasized. The authors conclude that loss of statistical information with a decrease in the number of latent values provides an attractive basis for comparing discrete and continuous latent variable models. Theoretical considerations as well as the results of 2 Monte Carlo simulations indicate that information theory provides a sound basis for modeling latent distributions and distinguishing between discrete and continuous latent variable models in particular.

Behavioral Sciences↗

Information theory based T7-like promoter models: classification of bacteriophages and differential evolution of promoters and their polymerases.

Molecular information theory was used to create sequence logos and promoter models for eight phages of the T7 group: T7, phiA1122, T3, phiYeO3-12, SP6, K1-5, gh-1 and K11. When these models were used to scan the corresponding genomes, a significant gap in the individual information distribution was observed between functional promoter sites and other sequences, suggesting that the models can be used to identify new T7-like promoters. When a combined 76-site model was used to scan the eight phages, 108 of the total 109 promoters were found, while none were found for other T7-like phages, phiKMV, P60, VpV262, SIO1, PaP3, Xp10, P-SSP7 and Ppu40, indicating that these phages do not belong to the T7 group. We propose that the T7-like transcription system, which consists of a phage-specific RNA polymerase and a set of conserved T7-like promoters, is a hallmark feature of the T7 group and can be used to classify T7-like phages. Phylogenetic trees of the T7-like promoter models and their corresponding RNA polymerases are similar, suggesting that the eight phages of the T7 group can be classified into five subgroups. However the SP6-like polymerases have apparently diverged from other polymerases more than their promoters have diverged from other promoters.

DNA-Directed RNA Polymerases↗

Assessment of geometrical distortion and activity distribution after attenuation correction: A SPECT phantom study.

BACKGROUND: If single photon emission computed tomography (SPECT) images are reconstructed with filtered backprojection (FBP), not accounting for photon attenuation, artifacts can occur related to geometrical distortion and inaccurate estimation of regional distribution of radioactivity. By reconstructing the images with an iterative algorithm such as the maximum likelihood-expectation maximization (ML-EM) that incorporates the attenuation distribution information, it is possible to compensate for nonuniform attenuation. The aim of this study was to assess whether correction for nonuniform attenuation in SPECT can reduce the geometrical distortion and improve the activity quantitation. METHODS AND RESULTS: Three capillary sources containing the same amount of technetium 99m were imaged by a dual-headed SPECT system provided with two gadolinium 153 scanning transmission line sources, in nonuniform attenuation conditions. The images were reconstructed (1) with the use of FBP, (2) with the iterative ML-EM algorithm, and (3) with the iterative ML-EM algorithm incorporating attenuation maps. The geometrical distortion was estimated by comparing the spread that occurred in 2 orthogonal directions in the reconstructed transverse slices, expressed by full width at half maximum related to the x-axis and y-axis line spread functions. The accuracy of activity quantitation was analyzed by comparing the counts in regions of interest placed over the transverse slices of the 3 sources, located in different attenuating areas. The FBP-reconstructed slices showed a spread of image intensity toward the direction of minor attenuation; the source shape improved in the iterative ML-EM images, as well as in the iterative attenuation-corrected ML-EM images. The sources located deep in the phantom showed an apparent decrease in image intensity in both FBP and ML-EM images, which became less evident in the iterative attenuation-corrected ML-EM images. CONCLUSIONS: Image reconstruction with the iterative ML-EM algorithm, without the use of attenuation maps, can reduce geometrical distortion and eliminate streak artifacts, leading to an improvement in the object's shape and size, but does not reduce activity underestimation and inaccurate quantitation. In the iterative attenuation-corrected ML-EM images, there was a significant improvement in the accurate quantitation of activity distribution and a further reduction in geometrical distortion. In conclusion, nonisotropic attenuation correction with iterative ML-EM reduced the geometrical distortion of images and improved the accuracy of activity quantitation.

Abdomen↗

Projected uptake and toxicity of selenium compounds from the environment.

Industrial workers and members of the general public may be exposed to selenium by inhalation of selenium in the workplace or atmosphere or by ingestion of selenium in food. A model has been developed to evaluate the potential uptake of selenium in body tissues by these two exposure routes. Rates were estimated for transport of selenium between five compartments including lung, gastrointestinal tract, blood, liver and other tissues. Results of model simulations were compared to published tissue distribution information obtained from single inhalation exposures of rats and dogs to radiolabeled selenium compounds at concentrations from 20 mg/m3 to 20 micrograms/m3 with initial body burdens of selenium ranging from 28 to 0.09 micrograms Se/kg body wt. The model was then modified to predict equilibrium organ concentrations of selenium in people after continual exposure to selenium in the air or in the diet. Daily intake levels of 100 micrograms/day and a fractional absorption value of 0.8 were used. With an air concentration of 1 ng Se/m3, model predictions indicated that most of the total body selenium in people is likely to come from their diet because selenium in the urban atmosphere contributes a very small part of the total body selenium. However, continual inhalation of selenium at the threshold limit value (TLV; 200 micrograms/m3) could contribute significantly to the total body burden of selenium. Levels of selenium predicted in lung, liver, and blood after inhalation of selenium at the TLV were 22,000, 1200, and 440 ng Se/g tissue. Predicted lung concentrations were near those that produced toxic effects in animals after ingestion of Se.

Absorption↗

Premotor interneurons in generation of adaptive leg reflexes and voluntary movements in stick insects.

We investigated the role of local nonspiking interneurons involved in motor control of legs in the stick insects, Carausius morosus. In a preparation that allowed the animals to perform active leg movements such as adaptive tactile reflexes, proprioceptive reflexes, and walking, we gathered the following results. Almost all tested nonspiking interneurons that provide synaptic drive onto moto-neurons of the proximal leg muscles contribute to all of the motor programs underlying tactile reflexes and voluntary leg movements such as walking, searching, and rocking. Most of them are also involved in the generation of proprioceptive reflexes. All motor programs for coactivation, avoidance reflexes, resistance reflexes, and voluntary leg movements result from parallel pathways including nonspiking interneurons that support and others that oppose the motoneuronal activity. The contribution of a single interneuron to the different motor program is specific: it can be supporting for one motor program but opposing for the other. Even for the same motor program, for example, coactivation, the contribution of an individual interneuron can depend on the stimulus site from where the response is elicited. Our results support the idea that the different motor patterns for adaptive tactile reflexes, resistance reflexes, and voluntary leg movements emerge from a multifunctional neuronal circuit that is reorganized corresponding to the motor behavior performed. The actual motor pattern is then shaped by distributed information processing in parallel supporting and opposing pathways.

Acclimatization↗

Morphology of the cells within the inferior temporal gyrus that project to the prefrontal cortex in the macaque monkey.

The primate neocortex possesses an extraordinary degree of regional specialization. Virtually all cortical functions are dependent upon a complex system of reciprocal connections between related cortical regions that allow for distributed information processing. Although some aspects of the organization of these corticocortical projections are understood, little is known about the morphology and afferents to the cells of origin of long corticocortical projections in primates. We combined intracellular injection of Lucifer Yellow (LY) in fixed tissue with in vivo retrograde transport of fast blue to study the dendritic morphology of neurons within the inferior temporal gyrus (ITG) and the superior temporal sulcus (STS) that furnish corticocortical projections to the prefrontal cortex. The fast blue retrogradely labeled cells formed two clearly defined bands within the inferior temporal cortex: a supragranular band that corresponded to layer III, and an infragranular band that corresponded to layers V and VI. After Lucifer Yellow intracellular filling, these retrogradely labeled cells projecting to the prefrontal cortex were found to be morphologically very heterogeneous. Although all filled cells had spiny dendrites, they presented a wide range of cell body sizes and dendritic tree morphologies. In layer III, the majority of cells were typical pyramids of various sizes. In layers V-VI, numerous typical pyramidal cells were present. In addition, significant numbers of modified pyramidal forms were found, including vertical and horizontal fusiform cells, asymmetrical pyramids and multipolar cells. The entire dendritic arbor of individual subtypes in layers III, V, and VI was restricted to a few cortical layers, but as a group these cells had dendrites spanning the whole cortical depth. We suggest that corticocortically projecting cells are distinct from subcortically projecting cells and consist of a defined set of morphological and functional subgroups, each of which is driven by a distinct set of afferents and likely possesses different response properties.

Animals↗

Direct measurement of the end-to-end distance of individual polyfluorene polymer chains.

Wide-field imaging of individual multichromophoric molecules and successive photobleaching were used to determine, accurately, the relative position of the chromophores in such systems. First, a polyphenylene dendrimer with well-defined geometry was used to establish the accuracy in localization that can be obtained by this methodology. For a signal-to-noise ratio of 20, interchromophoric distances could be measured with 4 nm accuracy. Next, the method was used to determine the end-to-end distribution of an end-capped polyfluorene polymer. From comparison between the experimental and simulated distributions, information on the conformation of the polymer could be deduced. It was found that the polymer has a nonlinear conformation. A conjugation length of six monomer units gave the best fit of the experimental data to the proposed model.

Journal Article↗

Engineering mutations: deconstructing the mouse gene by gene.

Over the past years new vectors and methodologies have been developed to carry out large-scale genome-wide insertional mutagenesis screens in the mouse. Gene trapping, the most commonly used technique, is based on the insertion of a retroviral- or plasmid-based vector into a gene, resulting in a loss-of-function mutation, while simultaneously reporting its expression pattern and providing a molecular tag to facilitate cloning. The discovery of vertebrate DNA transposons in the mouse and recent improvements has also led to their increased use in insertional mutagenesis screens. Several public resources have been set-up recently by the academic community to distribute information and materials generated from these large-scale screens. These new resources should accelerate the study and understanding of biological and developmental processes.

Animals↗

Sizing of a vesicle drug formulation by quasi-elastic light scattering and comparison with electron microscopy and ultracentrifugation.

Quasi-elastic light scattering has been used for the sizing of a vesicle formulation. Porcine insulin was encapsulated in a vesicle preparation containing cholesterol, dipalmitoylphosphotidylcholine, digalactosyl digycerides, and dipalmitoylphosphotidylglycerol in a 40:40:15:5 ratio. The measurement requires less than 15 min to obtain mean size and distribution information and can be operated in a quality control environment. Advantages and limitations of quasi-elastic light scattering are described and this method is compared to electron microscopy and ultracentrifugation.

Chemistry, Pharmaceutical↗