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PubMedDate not supplied

Digital echocardiography and telemedicine applications in pediatric cardiology.

Digital echocardiography offers several advantages over videotape, including easy review, comparison, storage, postprocessing, and sharing of studies, quantitative analysis, and superior resolution. Newer echocardiography systems can write digital data to computer hardware, whereas older systems require digitization of analog data. Clinical and digital data compression is required to reduce study size. Clinical compression has been validated in several adult studies and one pediatric study. JPEG and MPEG digital compression ratios of 26:1 and 200:1, respectively, approximate S-videotape quality. JPEG is the DICOM 3.0 standard and is ideal for short loops, serial comparisons, and quantitative analysis. MPEG (the motion picture standard) lends itself to digitization of video streams and may be more attractive to pediatric cardiologists. Options for data storage and transfer range from limited local review to multiple offline review stations linked by a wide-area network. Telemedicine expands the capabilities of digital echocardiography in a "store and forward" or "real-time" format. Real-time neonatal telecardiology is accurate, impacts patient care, is cost-effective, and does not increase utilization. Cost, increased reliance on sonographers' skills, lack of accepted standards, and legal, licensure, and billing issues are obstacles to widespread acceptance of digital echocardiography and telemedicine.

Echocardiography↗
PubMed2005

In vitro expression of natriuretic peptides in cardiomyocytes differentiated from monkey embryonic stem cells.

Functional characterization of ES cell-derived cardiomyocytes is important for differentiation control and application to the cell therapy. One of the crucial functions of cardiomyocytes is a production of atrial and brain natriuretic peptides (ANP and BNP, respectively), which have important endocrine, autocrine, and paracrine functions. In this study, we focused on the functional aspect of the cardiomyocytes differentiated from monkey ES cells in vitro and investigated the expression of ANP and BNP. Spontaneously contracting cells showed nodal-like action potentials, and expression of ANP and BNP by RT-PCR and immunocytochemistry. Interestingly, ANP and BNP expressions were detected as immunoreactive granules in the perinuclear area and these signals appeared to co-localize with trans-Golgi network. These findings suggest that monkey ES cells were able to differentiate into cardiomyocytes with functional characteristics in vitro and therefore can be used as a useful model to study mechanisms and functions in early cardiogenesis.

Action Potentials↗
PubMed1998

A visuo-somatomotor pathway through superior parietal cortex in the macaque monkey: cortical connections of areas V6 and V6A.

This report addresses the connectivity of the cortex occupying middle to dorsal levels of the anterior bank of the parieto-occipital sulcus in the macaque monkey. We have previously referred to this territory, whose perimeter is roughly circumscribed by the distribution of interhemispheric callosal fibres, as area V6, or the 'V6 complex'. Following injections of wheatgerm agglutinin conjugated to horseradish peroxidase (WGA-HRP) into this region, we examined the laminar organization of labelled cells and axonal terminals to attain indications of relative hierarchical status among the network of connected areas. A notable transition in the laminar patterns of the local, intrinsic connections prompted a sub-designation of the V6 complex itself into two separate areas, V6 and V6A, with area V6A lying dorsal, or dorsomedial to V6 proper. V6 receives ascending input from V2 and V3, ranks equal to V3A and V5, and provides an ascending input to V6A at the level above. V6A is not connected to area V2 and in general is less heavily linked to the earliest visual areas; in other respects, the two parts of the V6 complex share similar spheres of connectivity. These include regions of peripheral representation in prestriate areas V3, V3A and V5, parietal visual areas V5A/MST and 7a, other regions of visuo-somatosensory association cortex within the intraparietal sulcus and on the medial surface of the hemisphere, and the premotor cortex. Subcortical connections include the medial and lateral pulvinar, caudate nucleus, claustrum, middle and deep layers of the superior colliculus and pontine nuclei. From this pattern of connections, it is clear that the V6 complex is heavily engaged in sensory-motor integration. The specific somatotopic locations within sensorimotor cortex that receive this input suggest a role in controlling the trunk and limbs, and outward reaching arm movements. There is a secondary contribution to the brain's complex oculomotor circuitry. That the medial region of the cortex is devoted to tightly interconnected representations of the sensory periphery, both visual and somatotopic-which are routinely stimulated in concert-would appear to be an aspect of the global organization of the cortex which must facilitate multimodal integration.

Animals↗
PubMed1995

[The doctrine of brain localization and its development in the 20th century].

The discovery of the cerebral motor cortex in the last third of the 19th century has decisively influenced the doctrine of cerebral localization. It has dominated brain research from there on. Its considerable practical importance for focalized local diagnosis was recognized from the clinical point of view. As a consequence, interdisciplinary institutions for brain research developed in Europe and in the USA for the study of functional localization in the brain by means of cyto- and myeloarchitecture, electrical brain stimulation and lesion experiments in close connection with clinico-neurologic centers. From this research resulted the cerebral cortical maps with more or less numerous areas linked to either sensory, motor or 'higher' psychic functions. An intensive, emotional critique developed against the brain-localization theory from its onset. This article demonstrates that the arguments of the anti-localizationists gave rise in part to new knowledge about some principles of cerebral function. Some of these are the concept of 'diaschisis' (distant effects of acute lesions and functional recovery, von Monakow, 1902), the concept of 'motor equivalence' (Lashley, 1930) and of neuronal plasticity of the cerebral cortex (Cajal, 1911). Furthermore, modern imaging techniques (position emission tomography, functional nuclear spin resonance) show that complex functions in particular, such as the natural, targeted arm and grasp synergy, are not 'localized' within a small area of the cortex but do activate multiple neuronal networks interconnected dynamically and in alternating composition in the process of movement initiation and execution.

Brain↗
PubMedDate not supplied

[The temporal organization of the interneuronal frontal-motor relations in the cat neocortex depending on the level of food motivation].

The multiunit activity in the frontal and sensorimotor cortex was recorded by the bundle of nichromic electrodes in waking cats with different levels of alimentary motivation. Interaction between the neighbouring and distant neurons was evaluated by means of statistical cross-correlation analysis of spike trains. It was shown that the 24-hour food deprivation increased the number of correlations between discharges of the neurons both in the local (between the neighbouring neurons in the frontal and sensorimotor areas) and distributed networks (interarea correlations between the frontal and sensorimotor cortical neurons) with delays in the range of 0-100 ms. This increase was most significant in the delay range of 0-30 ms.

Action Potentials↗
PubMed2002

Analysis of polynuclear aromatic hydrocarbons via the Voronoi tessellation approach: classification of atom types using artificial neural networks.

When identifying the correct atom types to occupy the specific atomic locations within newly observed structures or when assessing the plausibility of new suggested structures with specific locations for specific types of atoms, any information quantifying geometrically the local environments around those locations is valuable, provided known characteristic differences exist, with respect to this geometric information, between the different atom types. A powerful tool for quantifying such geometries is the Voronoi tessellation; this has been used in a pilot study of polynuclear aromatic hydrocarbons. It has been found that perfect identification of all C and H atoms may be achieved through the examination of polyhedral volumes and surface areas. The use of a weighted face-area average is also found to be a useful measure of local structure. Simple neural network models that may be used for atom-type prediction are given in the paper. It is expected that the present approach will be useful in distinguishing between atoms that have close scattering curves whilst displaying similar crystallographic behaviour.

Algorithms↗
PubMed2002

Metabotropic glutamate receptors control gating of spike transmission in the hippocampus area CA1.

Signal transmission in the brain is regulated by a number of filters and modulatory systems. In particular, theta rhythm modulates local inhibition of networks and facilitates the induction of synaptic plastic processes. Additionally, the transmission of spikes in the network is controlled by pulse facilitation as a noise filter. Metabotropic glutamate receptors (mGluRs) that are found on interneurons in area CA1 of the hippocampus play a role in the fine-tuning of inhibitory circuits and in the transmission of spikes through the network. It was found that the mGluR agonist 1S,3S-1-amino-cyclo-pentyl-1,3-dicarboxylic acid (1S,3S-ACPD) blocked the induction of long-term potentiation (LTP) by high-frequency stimulation (HFS). In addition, theta-patterned stimulation was blocked by the drug. However, learning of spatial tasks in the water maze or radial arm maze was not inhibited by 1S,3S-ACPD. Yet, when stimulating with short bursts phase-locked with theta rhythm at the low inhibition phase, 1S,3S-ACPD did not inhibit the development of LTP. This suggests that burst transmission is not blocked in the network, while high-frequency trains are reduced to prevent overexcitation and the transmission of nonphysiologic stimuli patterns.

Animals↗
PubMed1999

Patterns of gene flow inferred from genetic distances in the Mediterranean region.

The analysis of population structure may lead to inferences about demographic phenomena. In particular, regions of sharp genetic differentiation suggest the existence of factors that impaired gene flow and increased the evolutionary role of genetic drift. Here, we present an analysis of a data set of 10 allele frequencies in 39 populations of the Mediterranean region. As a preliminary step, we describe spatial patterns of allele frequencies using spatial autocorrelation analysis. We then construct a network connecting localities and estimate genetic distances along the edges of the network. By applying specific algorithms, we locate on the map the areas of sharpest genetic differentiation, or genetic boundaries. The main boundaries separate the northern and the southern coasts, especially in their western portions; in addition, several localities appear genetically isolated. The comparatively high genetic differentiation across the western Mediterranean, where the sea distances between localities are shorter, strongly suggests that the sea distance by itself can hardly be regarded as a major isolating factor among these populations. On the contrary, the decrease in genetic resemblance between populations of the 2 coasts as one proceeds westward may reflect an increased genetic exchange in the eastern Mediterranean basin or independent human dispersal along the 2 coasts or both.

Algorithms↗
PubMedDate not supplied

Interaction of double-stranded T4 DNA with cationic gel of poly(diallyldimethylammonium chloride).

Interaction between duplex T4 DNA and a slightly cross-linked cationic gel of poly(diallyldimethylammonium chloride) in aqueous media was studied by fluorescent microscopy. While short DNA chains such as plasmid DNAs penetrate into the gel and form a phase of polyelectrolyte complex with the cationic network, the genomic giant DNA chains of T4 phages form complexes only on local areas of the gel surface. The DNA/gel complex exhibited different characteristic morphologies depending on the conditions for preparing the complex, such as the DNA concentration, flux of the solution, and surface geometry of the gel: (1) In the interaction with the flat surface of film-type gel, compact round objects, which reflected a condensed state of single DNA chains, were observed. (2) In the interaction with partly dried gel, a characteristic pattern similar to propagating waves was formed on the gel surface. (3) When flux is generated for a concentrated DNA solution, long oriented fiberlike structures were formed, which consisted of ensembles of chains. The interaction with small pieces of mechanically decomposed gel leads to complete covering of their surface by the DNA.

Bacteriophage T4↗
PubMed1994

Binocular disparity discrimination in human cerebral cortex: functional anatomy by positron emission tomography.

Neurobiological studies in higher primates indicate that the processing of stereoscopic information takes place at early levels in the visual cortex. To map the anatomical structures in the human brain participating in pure stereopsis based upon binocular disparity, we measured with positron emission tomography the changes in regional cerebral blood flow as an indicator of metabolic activity in 10 healthy young men during visual discrimination of binocular disparity. The data demonstrate that the discrimination of pure stereo-optic disparity information takes place in the polar striate cortex and the neighboring peri-striate cortices, as well as in the parietal lobe, the prefrontal cortex, and the cerebellum. The discrimination of stereoscopic depth is dependent on a network composed of multiple functional fields localized in occipital- and parietal-lobe visual areas as well as in the dorsolateral and mesial prefrontal cortex. The findings support the importance of coactivated occipitoparietal visual areas in the processing and analysis of binocular depth information in humans.

Adult↗
PubMedDate not supplied

Beyond the hospital walls. Saint Raphael's vision of care includes jobs, home loans, and a reading room.

Saint Raphael Health System is based in inner-city New Haven, CT, an area plagued by poverty, unemployment, and high infant mortality. Its leaders have long realized that healthcare involves more than curing diseases and patching wounds. Thus, in 1922, they launched Saint Raphael's Neighborhood Plan, which has five main components. The Neighborhood Reading Room, in a police substation, gives children a place to read, do homework, and get off the streets. The Neighborhood Home Ownership program helps Saint Raphael employees buy homes in the neighborhood. The Neighborhood Scholarships program gives eligible residents an opportunity to study full time at a state university or vocational school. The Neighborhood Career Counseling and Job Skills Assistance program has enabled Saint Raphael to hire 30 neighborhood residents and help others find jobs elsewhere. Reaching beyond its immediate neighborhood, Saint Raphael also operates school-based health centers, clinics for elderly, a mobile clinic for pregnant women and new mothers, a parish nurse program in 21 area churches and congregations, and a home care network. In addition, Saint Raphael is working with the local United Way and other organizations to conduct a community needs assessment; working with Yale University and other organizations to increase neighborhood stability; and operating a program for the early detection of breast and cervical cancer in uninsured and underinsured women.

Adult↗
PubMed2001

Parallel-distributed processing in olfactory cortex: new insights from morphological and physiological analysis of neuronal circuitry.

A working hypothesis is proposed for piriform cortex (PC) and other olfactory cortical areas that redefines the traditional functional roles as follows: the olfactory bulb serves as the primary olfactory cortex by virtue of encoding 'molecular features' (structural components common to many odorant molecules) as a patchy mosaic reminiscent of the representation of simple features in primary visual cortex. The anterior olfactory cortex (that has been inappropriately termed the anterior olfactory nucleus) detects and stores correlations between olfactory features, creating representations (gestalts) for particular odorants and odorant mixtures. This function places anterior olfactory cortex at the level of secondary visual cortex. PC carries out functions that have traditionally defined association cortex--it detects and learns correlations between olfactory gestalts formed in anterior olfactory cortex and a large repertoire of behavioral, cognitive and contextual information to which it has access through reciprocal connections with prefrontal, entorhinal, perirhinal and amygdaloid areas. Using principles derived from artificial networks with biologically plausible parallel-distributed architectures and Hebbian synaptic plasticity (i.e. adjustments in synaptic strength based on locally convergent activity), functional proposals are made for PC and related cortical areas. Architectural features incorporated include extensive recurrent connectivity in anterior PC, predominantly feedforward connectivity in posterior PC and backprojections that connect distal to proximal structures in the cascade of olfactory cortical areas. Capabilities of the 'reciprocal feedforward correlation' architecture that characterizes PC and adjoining higher-order areas are discussed in some detail. The working hypothesis is preceded by a review of relevant anatomy and physiology, and a non-quantitative account of parallel-distributed principles. To increase the accessibility of findings for PC and to advertise its substantial potential as a model for experimental and modeling analysis of associative processes, parallels are described between PC and the hippocampal formation, inferotemporal visual cortex and prefrontal cortex.

Animals↗
PubMed1997

Instrumental conditioning of fast (20- to 50-Hz) oscillations in corticothalamic networks.

Cats were instrumentally conditioned to generate grouped fast (20- to 50-Hz) oscillations in motor cortex (area 4). Over seven experimental sessions, there was a spatially selective increased generation of grouped fast oscillations in that electroencephalogram lead. This locally increased generation of fast oscillations in cortex was associated with a widespread increase in synchrony of fast oscillations in thalamocortical networks, as demonstrated by cross-correlations between intracortical, corticothalamic, and intrathalamic field potentials. A three-session extinction period abolished the local increase in generation of grouped fast oscillations and reset the thalamocortical synchrony of fast oscillations to control values. A subsequent series of seven sessions with instrumental conditioning of fast oscillations in visual cortex (area 17) reproduced the results from area 4, with a spatially selective increased generation of grouped fast oscillations in the criterion lead, associated with a widespread increase in thalamocortical synchrony of fast oscillations. In addition to their presence during the conditioning sessions, the changes in synchrony of fast oscillations were expressed during periods of quiet waking, rapid-eye-movement sleep, and nonrapid-eye-movement sleep recorded during the first hour after the end of the conditioning.

Animals↗
PubMedDate not supplied

Nursing leadership succession planning in Veterans Health Administration: creating a useful database.

An electronic database was developed for succession planning and placement of nursing leaders interested and ready, willing, and able to accept an assignment in a nursing leadership position. The tool is a 1-page form used to identify candidates for nursing leadership assignments. This tool has been deployed nationally, with access to the database restricted to nurse executives at every Veterans Health Administration facility for the purpose of entering the names of developed nurse leaders ready for a leadership assignment. The tool is easily accessed through the Veterans Health Administration Office of Nursing Service, and by limiting access to the nurse executive group, ensures candidates identified are qualified. Demographic information included on the survey tool includes the candidate's demographic information and other certifications/credentials. This completed information form is entered into a database from which a report can be generated, resulting in a listing of potential candidates to contact to supplement a local or Veterans Integrated Service Network wide position announcement. The data forms can be sorted by positions, areas of clinical or functional experience, training programs completed, and geographic preference. The forms can be edited or updated and/or added or deleted in the system as the need is identified. This tool allows facilities with limited internal candidates to have a resource with Department of Veterans Affairs prepared staff in which to seek additional candidates. It also provides a way for interested candidates to be considered for positions outside of their local geographic area.

Career Mobility↗
PubMed1998

Functional imaging of mirror and inverse reading reveals separate coactivated networks for oculomotion and spatial transformations.

Echoplanar functional magnetic resonance imaging (fMRI) was used to localize the cortical areas involved in the analysis of spatially transformed letter strings. Significant increases of the blood oxygen level-dependent (BOLD) signal for transformed vs normal reading were observed in the superior parietal lobule (SPL), along the intraparietal sulcus (IPS), in the frontal eye fields (FEF), and in the latero-occipital area LO. The respective contributions of oculomotor and spatial transformation areas to this activation pattern were separated by means of a control condition involving the execution and suppression of eye movements. Areas activated in association with the control of eye movements included the superior parietal lobule and the frontal eye fields. The cooperation of different brain areas was analysed by correlating the time course of task-dependent BOLD signal changes in these areas. This correlation analysis revealed coactivation of occipitotemporal object recognition areas and a spatial transformation area in the intraparietal sulcus during the reading of transformed letter strings. We suggest that cortical systems that are coactivated during complex cognitive tasks can be differentiated by the correlation analysis of BOLD signal time courses in spatially separate brain areas.

Adult↗
PubMedDate not supplied

New mother groups as a social network intervention: consumer and maternal and child health nurse perspectives.

Maternal and child health nurses in two outer urban local government areas in Melbourne, Australia were interviewed about how they facilitated first-time parent groups. Groups were offered to all first time mothers and almost two thirds of mothers joined a group. The groups ran for approximately eight sessions and provided infant-focussed parent education and social contact. Women who joined the groups were followed up 18 months to two years later to determine the degree to which these groups continued to meet on their own accord and the extent to which they had become self-sustaining social networks. The study found a very high level of continuation, suggesting that providing such programs may be an important vehicle for enhancing social support during the transition to parenthood and thus be a useful primary prevention strategy.

Adult↗
PubMed1996

Cytoplasmic and nuclear localization sites of phosphatidylinositol 3-kinase in human osteosarcoma sensitive and multidrug-resistant Saos-2 cells.

The intracellular localization of phosphatidyl-inositol 3-kinase (PI 3-kinase) has been analyzed by western blotting, confocal, and electron microscopy immunocytochemistry in human osteosarcoma Saos-2 cells. By western blotting, the enzyme appears to be present in both the cytoplasmic and nuclear subfractions. By confocal microscope immunocytochemistry, the cytoplasmic fluorescence is localized in the perinuclear region and on a network of filaments, while a diffused signal is present in the nucleus, except for the nucleolar areas. Ultrastructural analyses on whole cells and on in situ matrix preparations reveal that nuclear PI 3-kinase is localized in interchromatin domains, in stable association with inner nuclear matrix components, while the enzyme diffused in the cytosol is partly associated with the cytoskeletal filaments. Quantitative evaluations indicate that, in a multidrug-resistant variant obtained by continuous exposure of Saos-2 cells to doxorubicin, the amount of nuclear and cytoplasmic PI 3-kinase is significantly lower than in the sensitive parental cell line. The nuclear localization of PI 3-kinase and its variation in multidrug-resistant cells, characterized by a reduced mitotic index, are consistent with the data on the existence of a nuclear inositol lipid cycle, which could also utilize 3-phosphorylated inositides to modulate signal transduction for the control of some key functional activities.

Blotting, Western↗
PubMed1997

Patterned delivery of immunoglobulins to surfaces using microfluidic networks.

Microfluidic networks (microFNs) were used to pattern biomolecules with high resolution on a variety of substrates (gold, glass, or polystyrene). Elastomeric microFNs localized chemical reactions between the biomolecules and the surface, requiring only microliters of reagent to cover square millimeter-sized areas. The networks were designed to ensure stability and filling of the microFN and allowed a homogeneous distribution and robust attachment of material to the substrate along the conduits in the microFN. Immunoglobulins patterned on substrates by means of microFNs remained strictly confined to areas enclosed by the network with submicron resolution and were viable for subsequent use in assays. The approach is simple and general enough to suggest a practical way to incorporate biological material on technological substrates.

Adhesiveness↗