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PubMed1998

[Severity of obstructive sleep apnea syndrome relates to sleep architecture changes].

OBJECTIVE: To explore how obstructive sleep apnea syndrome (OSAS) affects sleep architecture and if OSAS severity and treatment relate to it. METHOD: A computer-assistant diagnostic system was used for polysomnography(PSG) recording. Respiratory events were scored automatically and corrected manually. Sleep was scored manually according to the standard set by Rechtschaffen. 31 controls and 147 OSAS patients(RDI > or = 5) were defined by PSG. 11 OSAS patients(RDI = 62.5 +/- 20.8) accepted nCPAP therapy. PSG were recorded both before and during nCPAP treatment. RESULT: (1) Compared with controls, OSAS group had increased sleep shift number (120 +/- 71 vs 92 +/- 60, P = 0.0106); (2) The number of slow wave sleep(SWS) (5 +/- 9 vs 8 +/- 8, P = 0.0035) and the ratio of total SWS time over total sleep time(TST) (5% +/- 8% vs 8% +/- 9%, P = 0.0062), were decreased and the rate of SWS deprivation(48% vs 26%, P < 0.05) were increased greatly in OSAS patients; (3) REM were less affected by OSAS than SWS because the ratio of its total time over TST, its onset number and deprivation rate had no significant difference between the two groups; (4) OSAS group had increased number of WASO (wake after sleep onset) (27 +/- 28 vs 19 +/- 18, P = 0.017) but the ratio of total WASO time over total sleep period had no significant difference between the two groups; (5) The ratio of total RWS(rapid wave sleep) time over TST (94 +/- 10 in OSAS group vs 91 +/- 12, P = 0.0136) and total RWS number(88 +/- 54 in OSAS group vs 65 +/- 45, P = 0.0075) were increased in OSAS group; (6) The above parameters were obviously disturbed in OSAS patients with RDI > or = 25 but had almost no change in patients with RDI < 25 compared with controls. (7) nCPAP could improve the above parameters but only number of WASO(no therapy: 34 +/- 20 vs therapy: 23 +/- 22, P = 0.011), shift number (no therapy: 151 +/- 62 vs therapy: 97 +/- 50, P = 0.019) and the ratio of total RWS time over TST (no therapy: 115 +/- 58 vs therapy: 69 +/- 34, P = 0.025) had statistical significance. CONCLUSION: OSAS severity relates to sleep architecture changes. Those had RDI < 25 had no change compared with control group. Sleep architecture changes could be improved by effective nCPAP therapy.

Adult↗
PubMed2001

Architecture of the sperm cell of Psilotum.

In this correlated SEM (scanning electron microscope) and TEM (transmission electron microscope) investigation, we describe architectural details of the multiflagellated sperm cell of Psilotum nudum. Comparisons with other pteridophytes are made to (1) assess the placement of Psilotum among pteridophyte taxa and (2) evaluate structural modifications of sperm cells during land plant evolution. The released spermatozoid of Psilotum coils 2.0 revolutions and is outlined by a parallel band of up to 190 microtubules. The elongated nucleus is highly compacted and parallels the cellular coils with numerous mitochondria and starch-laden plastids distributed along its length. Along the anterior coil is an elaborate locomotory apparatus that includes ∼36 flagella that are inserted into the cell by basal bodies. Subtending the basal bodies is the multilayered structure, which consists of a long narrow lamellar strip and an overlying band of microtubules. An elongated anterior mitochondrion underlies the multilayered structure. Additional amyloplasts and mitochondria are aggregated along the anterior coil in association with the locomotory apparatus, while a fibrous band encircles the leading edge of the cell. Salient features of this cell, including details of the locomotory apparatus, structure and position of organelles, and arrangement of the spline, are shared by spermatozoids of Equisetum and ferns (including eusporangiate and leptosporangiate taxa). Thus, this study provides morphological support for the hypothesis that Psilotum nudum is a member of an assemblage that includes ferns and Equisetum. However, the less streamlined architecture of Psilotum gametes and the lack of architectural features shared with any specific taxon examined to date suggest that Psilotum is an early divergent fern, with relatively remote affinities to Ophioglossaceae and Equisetaceae.

Journal Article↗
PubMed2001

Architectural-based interpretations of breast MR imaging.

Architectural features extracted from high spatial resolution MR images of the breast can help distinguish malignant from benign breast abnormalities and can help predict specific histopathologic diagnoses. Various breast pathologies consistently display certain MR architectural features. Individual architectural features have been incorporated into interpretation models that can improve the diagnostic performance of MR imaging over the use of individual features alone.

Breast Neoplasms↗
PubMed1998

Changes in human muscle architecture in disuse-atrophy evaluated by ultrasound imaging.

The aim of this study was to investigate if changes in muscle architecture occurred as a result of disuse-atrophy. Anatomical cross-sectional area (ACSA), muscle volume (V), fibre length (Lf) and pennation angle (theta) of the gastrocnemius medialis (GM) were evaluated by MRI and real-time ultrasound in 8 male patients with unilateral lower limb atrophy. The architectural data of the injured (I) and uninjured (UN) legs were compared. Values are means +/- S.E.M. The GM ACSA was 23.1 +/- 2.8% smaller in the I leg (P<0.001). Both theta and Lf of the I leg GM were respectively smaller by 16.42 +/- 2.9% (P<0.001) and 12.7 +/- 1.9% (P<0.001) than of the UN leg GM. The decrease of GM ACSA was highly correlated (P<0.001, R2=0.925) with the decrease in theta. It is concluded that disuse muscle atrophy leads to significant changes in muscle architecture.

Adult↗
PubMed1983

Molecular architecture of fungal cell walls. An approach by use of fluorescent markers.

Fluorescent probes have been applied to analyze the molecular architecture of fungal cell surfaces. Binding patterns of aniline blue and FITC-labeled wheat germ agglutinin (FITC-WGA) elucidated class-specific properties. Aniline-blue-induced fluorescence was distributed over the entire cell walls from Ascomycetes, but was confined to sporangial walls of Zygomocetes, hyphal tips and a few other sites in Basidiomycetes, while no fluorescence was found with sporangia and rhizoids of Chytridiales. FITC-WGA in Zygomycetes and in Ascomycetes was restricted to few sites (e.g. apex of hyphae), in Basidiomycetes and Chytridiales label was evenly associated with the entire surface of hyphal walls, or sporangia and rhizoids. For Oomycetes, Zygomycetes, Ascomycetes, and Basidiomycetes differences in the molecular architecture between apex and hyphal side walls were discerned, although the chemical nature of these differences is distinct for each class. Species specific differences, due to differences in binding patterns of several lectins are not apparent at fungal cell surfaces. The degree of intraspecies variation was found to be larger than interspecies diversification, suggesting changeableness of the molecular architecture of fungal cell walls. This is in contrast to assertions which we made by working on algae. There species-specific lectin binding patterns have been described.

Ascomycota↗
PubMed2001

Integrating medical applications in an open architecture through generic and reusable components.

Allowing exchange of information and cooperation among network-wide distributed and heterogeneous applications is a major need of current health care information systems. It forces the development of open and modular integration architectures. Major issues in the development include defining a flexible and robust federation model, developing interaction and communication facilities as well as the mechanism insuring semantic interoperability. We developed generic and reusable software components to ease the construction of any integration platform. The Pilot and the Mediator Service components facilitate the execution of services and the meaningful transformation of information. They have been tested in the context of the SynEx European project to construct a multi-agents based integration architecture. The possibility of such architectures to take into account the issue of semantic interoperability is further discussed.

Computer Communication Networks↗
PubMed2002

[Delineation of the cisternal architecture with three-dimensional CT cisternography and its transparent imaging].

We used three-dimensional imaging of the cisternal architecture with perspective volume rendering of CT cisternography in patients with unruptured cerebral aneurysms. Selective changes in the opacity chart of computed tomographic values, based on the use of a function of downward slope, represented the contour of the structures located in the cisternal space. In addition to this, using a spiked peak curve, it was possible to show the contour of the outer wall of the cisternal structures as a series of rings, which provided a transparent view inside and/or outside the cistern through the spaces between the rings. Transparent imaging technique allowed direct visualization of the underlying objects and offered an extensive perspective view of the anatomical architecture of the cisternal structure, including an aneurysm, major basal arteries and optic pathway, in a single view. Three-dimensional CT cisternography may be a useful adjunct for the diagnosis of the cisternal architecture in relation to the surrounding cerebrospinal fluid, and for simulation of the surgical procedures considered for lesions occupying intra-cisternal space, including cerebral aneurysms.

Aged↗
PubMed2002

An objective measure of architectural complexity and proliferative index in Gleason pattern 3 prostate cancer.

OBJECTIVE: To objectively characterize the architectural spectrum of Gleason pattern 3 prostate cancer (PCA) in a biologically meaningful manner. STUDY DESIGN: We define an objective architectural feature of PCA, "pinch point density" (PPD), and explore its relationship to proliferative index (PI). A pinch point (PP) is a site where the epithelium of two neighboring glandular structures is contiguous in one histologic section but not in an adjacent serial section. Seventeen radical prostatectomy specimens with areas of pure Gleason pattern 3 were studied. PPD was measured with computer aid using digital images of serial sections. PI was measured by computer-aided counting of Ki-67-positive cells. RESULTS: PPD correlated inversely with PI (PPD vs. log [PI], P < .004). Characteristics not significantly correlated with PI included total number of malignant glands, PP per gland and total number of malignant cells. Subjectively, tumors with high PPD and low PI tended to contain a larger number of smaller glands as compared to tumors with low PPD and high PI. This impression was confirmed analytically. CONCLUSION: PPD is an objective architectural feature of possible biologic significance. This is an early step toward identifying objective features of growth pattern in Gleason pattern 3 PCA that may be clinically meaningful.

Cell Division↗
PubMed2002

[The effect of rhodiola and acetazolamide on the sleep architecture and blood oxygen saturation in men living at high altitude].

OBJECTIVE: To study the changes of sleep architecture and blood oxygen saturation (SaO(2)) during sleep in men living at high altitude, and to investigate the effect of rhodiola and acetazolamide on these sleep indexes. METHODS: Twenty-four men aged 18 to 21 years who had stayed at high altitude (5 380 m above sea level) for 1 year were randomly divided into groups A (treated with oral rhodiola), B (treated with oral acetazolamide) and C (treated with rhodiola + acetazolamide). Their sleep architecture and SaO(2) were recorded for 24 days before and after taking the medicines. RESULTS: Compared with baseline, the waking SaO(2) (WSaO(2)), the lowest SaO(2) (LSaO(2)) and the mean SaO(2) (MSaO(2)) were increased significantly after treatment for 24 days (P < 0.01), and the times of oxygen desaturation >/= 4% per hour (DI4) and the percentage of time spent at SaO(2) below 80% (SIT(80)) were decreased significantly (P < 0.01). After treatment, the NREM I and II was shortened, and III + IV and REM sleep were prolonged (P < 0.01): the total waking time (TWT) was shortened, and the sleep efficiency index (SEI) was markedly increased (P < 0.01). Compared with group A's, groups B's and C's SIT(80) were increased (P < 0.05). CONCLUSION: Both rhodiola and acetazolamide were effective in modulating the sleep architecture and improving the sleep quality in young men living at high altitude, but there was no synergistic effect between rhodiola and acetazolamide.

Acetazolamide↗
PubMed2003

A general architecture for intelligent tutoring of diagnostic classification problem solving.

We report on a general architecture for creating knowledge-based medical training systems to teach diagnostic classification problem solving. The approach is informed by our previous work describing the development of expertise in classification problem solving in Pathology. The architecture envelops the traditional Intelligent Tutoring System design within the Unified Problem-solving Method description Language (UPML) architecture, supporting component modularity and reuse. Based on the domain ontology, domain task ontology and case data, the abstract problem-solving methods of the expert model create a dynamic solution graph. Student interaction with the solution graph is filtered through an instructional layer, which is created by a second set of abstract problem-solving methods and pedagogic ontologies, in response to the current state of the student model. We outline the advantages and limitations of this general approach, and describe it's implementation in SlideTutor - a developing Intelligent Tutoring System in Dermatopathology.

Artificial Intelligence↗
PubMed2002

Comparing concepts for electronic health record architectures.

Keeping all relevant information directly or indirectly related to patient's care, electronic health records (EHR) systems are supposed to be kernel application for any kind of health information systems. For facilitating shared care, managed care, or disease management, such EHR systems have to be scalable, portable, distributed, and interoperable which has to be enabled by a proper architecture supporting informational and functional needs as well. Advanced EHR architectures are based on object-oriented or component-oriented paradigms and use modern tooling to design, specify, implement and maintain EHR solutions. They reflect not only medical information but also underlying concepts and integrate an extended vocabulary. The most advanced EHR architecture approaches CEN ENV 13606, G-CPR, HL7 RIM and derived models, and finally the Australian GEHR project are shortly characterised. For comparing the solutions, the ISO RM - ODP, the Generic Component Model and the CORBA 3 methodology have been used. The HARP methodology for enhancing the current harmonisation of openEHR is shortly discussed.

Computer Systems↗
PubMed2004

[Short-term and long-term influences of nasal continuous positive airway pressure to sleep architecture of obstructive sleep apnea hypopnea syndrome].

OBJECTIVE: To observe the short-term and long-term influences of nasal continuous positive airway pressure (nCPAP) to sleep architecture of obstructive sleep apnea hypopnea syndrome (OSAHS). METHODS: Thirty cases who were diagnosed as OSAHS patients by polysomnography (PSG) were enrolled in the study. They received the nCPAP treatment in hospital at first night and then at home. Seventeen healthy adults were enrolled as control group and experienced PSG monitoring and recording. The sleep architectures of control group and OSAHS group (before nCPAP, first night on the nCPAP and 6 months after continuous nCPAP treatment) were analysed. RESULTS: The sleep shift number, first stage sleep, second stage sleep, stage of slow wave sleep and stage of rapid eye movement (REM) sleep were 34.41 +/- 10.16, (5.95 +/- 3.89)%, (48.13 +/- 7.68)%, (18.30 +/- 4.71)%, and (26.83 +/- 6.65)%, respectively, in control group. These parameters in OSAHS group before nCPAP were 207.30 +/- 149.80, (21.42 +/- 10.17)%, (55.24 +/- 13.28)%, (15.38 +/- 19.57)%, and (10.15 +/- 7.82)%, respectively. At the first night of nCPAP treatment they were 55.77 +/- 25.04, (10.92 +/- 9.62)%, (50.19 +/- 13.34)%, (17.53 +/- 10.06)%, and (21.17 +/- 7.66)%, respectively. There were statistically significant differences between the PSG parameters before and after nCPAP treatment in OSAHS group (P < 0.05). After 6 months of nCPAP treatment, the stage of REM sleep was significantly shorter (P < 0.05), but the other parameters had no significant changes compared with those at the first night on nCPAP (P > 0.05). CONCLUSION: The sleep shift number and first stage sleep in OSAHS group were significantly increased, but the stage of REM sleep was significantly decreased than those in control group. The sleep architecture of OSAHS was significantly improved when the nCPAP treatment was given continuously.

Aged↗
PubMed2004

A versatile petri net based architecture for modeling and simulation of complex biological processes.

The research on modeling and simulation of complex biological systems is getting more important in Systems Biology. In this respect, we have developed Hybrid Function Petri net (HFPN) that was newly developed from existing Petri net because of their intuitive graphical representation and their capabilities for mathematical analyses. However, in the process of modeling metabolic, gene regulatory or signal transduction pathways with the architecture, we have realized three extensions of HFPN, (i) an entity should be extended to contain more than one value, (ii) an entity should be extended to handle other primitive types, e.g. boolean, string, (iii) an entity should be extended to handle more advanced type called object that consists of variables and methods, are necessary for modeling biological systems with Petri net based architecture. To deal with it, we define a new enhanced Petri net called hybrid functional Petri net with extension (HFPNe). To demonstrate the effectiveness of the enhancements, we model and simulate with HFPNe four biological processes that are diffcult to represent with the previous architecture HFPN.

Algorithms↗
PubMed2004

A reference architecture for telemonitoring.

The Telecare Interactive Continuous Monitoring System exploits GPRS to provide an ambulatory device that monitors selected vital signs on a continuous basis. Alarms are sent when parameters fall outside preset limits, and accompanying physiological data may also be transmitted. The always-connected property of GPRS allows continuous interactive control of the device and its sensors, permitting changes to monitoring parameters or even enabling continuous monitoring of a sensor in emergency. A new personal area network (PAN) has been developed to support short-range wireless connection to sensors worn on the body including ECG and finger worn SpO2. Most notable is use of ultra low radio frequency to reduce power to minimum. The system has been designed to use a hierarchical architecture for sensors and "derived" signals, such as HR from ECG, so that each can be independently controlled and managed. Sensors are treated as objects, and functions are defined to control aspects of behaviour. These are refined in order to define a generic set of abstract functions to handle the majority of functions, leaving a minimum of sensor specific commands. The intention is to define a reference architecture in order to research the functionality and system architecture of a telemonitoring system. The Telecare project is funded through a grant from the European Commission (IST programme).

Body Temperature↗
PubMed2005

[Changes in sleep architecture by resumption of CPAP in patients with sleep apnea syndrome].

It is known that application of continuous positive airway pressure (CPAP) improves sleep architecture in patients with sleep apnea syndrome (SAS). In contrast, there have been only a few studies which deal with deterioration of sleep architecture by discontinuation of CPAP. In the present study we analyzed changes of sleep architecture by temporary removal of CPAP. The subjects were 41 patients who underwent polysomnography (PSG) for diagnosis of SAS. The patients chose either a 1-night study in which only PSG was done, or a 2-night study in which, after treatment with CPAP for one month, PSGs with and without CPAP at night were done. The mean ages, heights, and weights between the 1-night group and the 2-night group were not statistically different The mean AHI of the 1-night group (38.9 +/- 5.0/hr; mean +/- SE) and that of the 2-night group (45.7 +/- 5.4/hr) were not significantly different. The mean AHI profoundly decreased (4.4 +/- 0.9) by CPAP therapy on the second night. Percents of each sleep stage in the 1-night group were as follows; stage 1, 31.8%; stage 2, 50.0%; stage (3 + 4), 2.8%: REM, 15.7%. In the 2-night group, stage 1 was 43.6%, significantly higher than that in the 1-night group, while stage 2 was 39.9%, which was significantly smaller. There were no significant difference in stage (3 + 4) and REM. When CPAP was again applied to the 2-night patients, stage 1 significantly decreased to 15.5%, while stage 2 (55.6%), stage (3 + 4) 6.7%, and REM (22.3%) increased significantly. Therefore, cessation of CPAP shifts the sleep stage from stage 2 to stage 1. Since stages 1 and 2 occupy approximately 80% of total sleep duration, the shift may have some physiological significance. Resumation of CPAP may have improved quality of life and day-time sleepiness by decreasing stage 1 sleep and increasing stages of deeper sleep and REM.

Continuous Positive Airway Pressure↗
PubMed2006

Expected and observed changes to descriptors of trabecular architecture with aging--a comparison of measurement techniques.

The fragility of trabecular bone depends not only on the amount of bone but also on its architecture. In order to assess fragility of bone, describe changes due to age, and monitor effect of disease or treatment, it is necessary to model the physical properties of trabecular bone architecture. An important feature of bone architecture is the degree of anisotropy (DA). Estimates of DA may be obtained from computed tomography data by characterizing orientation in images. Widely used image descriptors for estimating orientation in this setting include mean intercept length (MIL), line fraction deviation (LFD), star length distribution (SLD) and star volume distribution (SVD). In this study, estimates of DA computed via each of these image descriptors are compared on synthetic images for various combinations of trabecular thickness, separation and number. Estimates of DA are also computed for real images representing different stages of aging. It is found that estimates of DA vary substantially depending on the choice of image descriptor. In particular, the MIL tends to underestimate DA.

Absorptiometry, Photon↗
PubMed2005

Architectural quality criteria for hospital information systems.

An important part of hospital information systems (HIS) evaluation is the quality assessment of its architecture, i.e. the structure of its IT infrastructure. Therefore, quantitative architectural quality criteria are needed. On the basis of relevant architectural components of a HIS defined by 3LGM2, the following quality criteria were defined: functional redundancy, functional under-saturation, functional correspondence, informational redundancy, degree of heterogeneity and degree of computer-support. These quality criteria were implemented as part of the 3LGM2 tool, a modelling tool to create 3LGM2 conformant HIS models. For every 3LGM2 model and its components the relevant quality criteria are automatically calculated and presented. The defined quality criteria can be used for several information management purposes. Nevertheless they are not intended to make absolute statements about the HIS quality. To ensure their expressiveness, complete and consistent underlying 3LGM2 models are needed.

Computer Systems↗
PubMed2005

Key design elements of a data utility for national biosurveillance: event-driven architecture, caching, and Web service model.

The National Retail Data Monitor (NRDM) has monitored over-the-counter (OTC) medication sales in the United States since December 2002. The NRDM collects data from over 18,600 retail stores and processes over 0.6 million sales records per day. This paper describes key architectural features that we have found necessary for a data utility component in a national biosurveillance system. These elements include event-driven architecture to provide analyses of data in near real time, multiple levels of caching to improve query response time, high availability through the use of clustered servers, scalable data storage through the use of storage area networks and a web-service function for interoperation with affiliated systems. The methods and architectural principles are relevant to the design of any production data utility for public health surveillance-systems that collect data from multiple sources in near real time for use by analytic programs and user interfaces that have substantial requirements for time-series data aggregated in multiple dimensions.

Commerce↗