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In this contribution we review the possibility of establishing the depositional age and tectonic settings of metamorphosed carbonate rocks from continental collision zones in the East African-Antarctic Orogen. The geochemical characteristics of regionally distributed meta-carbonate rocks from the Highland Complex (HC) in Sri Lanka are considered in detail and compared with similar occurrences in East Antarctica, India, Madagascar and Africa. The variations seen in the Highland Complex of Sri Lanka imply that carbonate deposition was younging from west to east, spanning apparent ages from Mesoproterozoic to Neoproterozoic. In the case of East Antarctica, such variations are within the Neoproterozoic, whereas in southern India, Madagascar and Mozambique they have a broader age range possibly from the Paleoproterozoic to Mesoproterozoic. There is also clear evidence that some carbonates were deposited in an open ocean surrounding volcanic islands in the Mesoproterozoic. Shale-normalized REE patterns have typical signatures of open ocean deposition in a passive continental margin with variable continental input in platforms nearby to island arcs. In comparison to Phanerozoic equivalents, the absence of a Ce anomaly is most significant, whereas other parameters such as (Pr/Yb)SN, (Pr/Tb)SN, and (Tb/Yb)SN were used to evaluate relative enrichments of the LREE, MREE and HREE fractions that are characteristic of ambient seawater. Pronounced La, and Y anomalies with minor Eu and Gd anomalies and correlations of REE parameters and anomalies with carbon and oxygen isotopes, 87Sr/86Sr initial ratios and eNd values are evaluated for meta-carbonate rocks in the Proterozoic collision zone. The eNd values and Sr initial ratios suggest that basins in the western Mozambique Ocean that separated the East Gondwana from West Gondwana received contributions from Archean continental crust and ambient seawater, whereas the eastern Mozambique Ocean had REE contributions from specific cratonic continents in passive margins or from continental/volcanic island arcs in active margins.

BACKGROUND AND PURPOSE: Knowledge about predictors of the outcome of flow-diverter treatment is limited. The aim of this study was to predict the angiographic occlusion status after flow-diverter treatment with computational fluid dynamics using porous media modeling for decision-making in the treatment of large wide-neck aneurysms. MATERIALS AND METHODS: A total of 27 patients treated with flow-diverter stents were retrospectively analyzed through computational fluid dynamics using pretreatment patient-specific 3D rotational angiography. These patients were classified into no-filling and contrast-filling groups based on the O’Kelly-Marotta scale. The patient characteristics, morphologic variables, and hemodynamic parameters were evaluated for understanding the outcomes of the flow-diverter treatment. RESULTS: The patient characteristics and morphologic variables were similar between the 2 groups. Flow velocity, wall shear stress, shear rate, modified aneurysmal inflow rate coefficient, and residual flow volume were significantly lower in the no-filling group. A novel parameter, called the normalized residual flow volume, was developed and defined as the residual flow volume normalized by the dome volume. The receiver operating characteristic curve analyses demonstrated that the normalized residual flow volume with an average flow velocity of ≥8.0 cm/s in the aneurysmal dome was the most effective in predicting the flow-diverter treatment outcomes. CONCLUSIONS: It was established in this study that the hemodynamic parameters could predict the angiographic occlusion status after flow-diverter treatment.

Recent treatment for type 2 diabetes mellitus (T2DM) has included glucagon-like peptide-1 receptor agonist (GLP-1 RA), indicating clinical efficacy for better glucose variability. Subjects were seven patients with T2DM associated with the obese tendency. Their average age was 63.8 ± 21.7 years old (5 males, 2 females) who received a new administration of GLP-1 RA (Mean ± standard deviation). For GLP-1 RA, dulaglutide (TRULICITY R, single-dose pen) was administered by subcutaneous injection 0.75 mg once a week. Basal data at 0 month revealed that body weight 76.0 ± 11.6 kg, body mass index (BMI) 29.2 ± 11.6, blood C-peptide immunoreactivity (CPR) 2.68 ± 0.49 ng/mL, respectively. After the intervention of dulaglutide, decreased value of BMI for 3 and 6-9 months was 0.78 ± 0.45 and 1.16 ± 0.85, and HbA1c for 3 and 6-9 months was 1.60 ± 1.52% and 2.01 ± 1.44%, respectively. Though these cases have various complications besides T2DM, they showed clinical effects of weight reduction and lowering blood glucose. Diabetic treatment for current cases would suggest that GLP-1 RA would be effective in various situations such as a super-aged patient, medical practice in the remote area, family care and visiting nursing.

This study presents a new dynamic simulation tool that facilitates plant and control system design of thermal power plants. In order to provide flexibility in building plant and control systems, object-oriented modelling techniques are used to model individual plant components, and each component object model is based on the verified first principles model. Further, simulation models can be easily built by connecting individual component object models, similar to the procedure adopted in an actual plant, by using a user-friendly graphical user interface. This tool enables the design engineer to build a simulation model, execute the simulation during the design process, test an actual plant control system, and adjust the control parameters. It is a useful design tool that accelerates and enhances the plant and control system design process.

The ultrahigh-definition television (UDTV) camera system requires an image sensor having four times higher resolution and two times higher frame rate than the conventional HDTV systems. Also, an image sensor with a small optical format and low power consumption is required for practical UDTV camera systems. To respond to these requirements, we have developed an 8.3-M-pixel digital-output CMOS active pixel sensor (APS) for the UDTV application. It features an optical format of 1.25inch, low power consumption of less than 600 mW at dark, while reproducing a low-noise, 60-frames/s progressive scan image. The image sensor is equipped with 1920 on-chip 10-bit analog-to-digital converters and outputs digital data stream through 16 parallel output ports. Design considerations to reproduce a low-noise, high-resolution image at high frame rate of 60 fps are described. Implementation and experimental results of the 8.3-M-pixel CMOS APS are presented.

We investigated the dependence of the surface resistance ( R s ) in high-temperature superconductor (HTS) thin films on a dc magnetic field (parallel to the c -axis) and temperature. Measurements were done using the dielectric resonator method and superconducting magnet system. The YBa 2 Cu 3 O 7− δ (YBCO) and DyBa 2 Cu 3 O 7− δ (DyBCO) thin films produced by THEVA GmbH were prepared through a thermal co-evaporation method. The R s of the YBCO and DyBCO thin films increased with magnitude of a dc magnetic field. The R s (5 T)/ R s (0 T) of the DyBCO was lower than that of the YBCO thin films for the temperature region below 40 K. From the results of the field-cooled (FC) and zero-field-cooled (ZFC) measurements of R s , it was found that there was plenty of flux pinning in the DyBCO thin films compared with the YBCO thin films. These results indicate that the DyBCO thin films with much pinning centers are better for use in low temperature nuclear magnetic resonance applications.

We investigated the behavior of the surface resistance (R/sub s/) of high-temperature superconductor (HTS) thin films exposed to a dc magnetic field (parallel to the c-axis). Measurements were done using the dielectric resonator method and superconducting magnet system. The DyBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// (DyBCO) and YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// (YBCO) thin films (produced by THEVA GmbH) were prepared through a thermal co-evaporation method. The resonant frequency of the TE/sub 011/ mode in the resonator was approximately 22 GHz. A dc magnetic field of up to 5 T was applied vertically to two parallel superconducting thin films placed into a closed-type Cu cavity. R/sub s/ of the DyBCO and YBCO thin films increased as the applied dc magnetic field increased. The R/sub s/ ratio (defined as R/sub s/(5 T)/R/sub s/(0 T)) of the DyBCO and YBCO thin films at 4.5 K was approximately 5 and 50, respectively. These results indicate that the DyBCO thin film may be better for use in low-temperature nuclear magnetic resonance applications.

We examined the hetero-epitaxial growth of YBCO thin films on the a-cut plane sapphire substrates for the passive microwave applications, because the a-cut plane sapphire substrates have smaller in-plane anisotropy of the dielectric constant compared with that of r-cut plane sapphire substrates. The CeO/sub 2/ buffer layers and YBCO thin films were prepared by an inductive-coupled plasma sputtering method. We found that perfect in-plane alignment of the CeO/sub 2/ buffer layer could be obtained on the a-cut plane sapphire substrates. Also we could obtain the hetero-epitaxial YBCO thin films on CeO/sub 2//a-cut plane sapphire substrates. Tc of the YBCO thin films was approximately 89 K, and the surface resistance (Rs) of the YBCO thin films was approximately 1 m/spl Omega/ at 50 K and at 22 GHz, equivalently to values for YBCO thin films fabricated on the r-cut plane sapphire substrates.

We have examined the fabrication conditions of epitaxial CeO 2 films on a -plane sapphire substrates, and also examined epitaxial growth of YBa 2 Cu 3 O 7− δ (YBCO) films on CeO 2 / a -plane sapphire substrate. The θ /2 θ XRD analysis of these composite films revealed that grains of the CeO 2 and YBCO on CeO 2 / a -plane sapphire substrate were perpendicular to the substrate. From the φ-scan XRD measurement, we found that the four 1 0 2 φ-scan peaks of the YBCO film were observed and the peak positions were shifted by 45° compared with those of the CeO 2 films. From the peak shifts we could estimate that the angle between the [1 0 0] axis of the CeO 2 and the [1 0 0] axis of the YBCO was 45°. From temperature dependence of resistivity of the YBCO/CeO 2 / a -plane sapphire substrates, we obtained a zero-resistance temperature ( T C ) of 88.6 K. We found that their crystallinity and critical temperature ( T C ) were quite similar to those of YBCO film on CeO 2 / r -plane sapphire substrate. At the moment, YBCO thin films on a -plane sapphire are inferior to YBCO thin film on r -plane sapphire in terms of surface resistance.

To determine whether abnormal EKG findings could be predictive factors for death after a stroke event.Patients with acute cerebral infarction who were 35 to 98 years old during April 1996 through November 2000 were analyzed (n = 216). A standard 12-lead EKG was recorded for each patient after acute cerebral infarction. The authors prospectively investigated the association between abnormal EKG findings and the risk for death after stroke over a 1-year period.Using multivariate Cox proportional hazards models, the authors found age (hazard ratio of mortality per year 1.10, 95% CI 1.06 to 1.15, p0.001), sex (female; hazard ratio of mortality 3.42, 95% CI 1.43 to 8.19, p = 0.006), and the presence of Q-waves in more than two leads (hazard ratio of mortality 2.75, 95% CI 1.23 to 6.14, p = 0.013) were independently associated with death after stroke.The presence of Q-waves in more than two leads could be a predictive factor for death after acute cerebral infarction.

We have examined in-plane orientation of CeO2 buffer layers on c-plane and tilt-c-plane sapphire substrates. The tilt angles are 5°, 10° and 15°, which are defined as the angles between the c-plane and the surface planes of the sapphire substrates (called 5°, 10°, 15° tilt-c-plane substrates). The films were prepared by inductively coupled plasma sputtering. The in-plane orientation of the films was measured using X-ray φ-scan. φ-scan peaks of films fabricated on c-plane substrates appeared every nπ/6 or nπ/12 (n: integer), showing 12-fold or 24-fold symmetry. The in-plane orientation is influenced by the hexagonal symmetry of the sapphire c-plane. The degree of film orientation depends on the substrate temperature during preparation. On the other hand, we found weak 4-fold symmetry for films fabricated on 10° and 15° tilt-c-plane substrates. This suggests that we can obtain CeO2 films with perfect 4-fold symmetry on tilt-c-plane sapphire substrates.

Thermoreversible gels formed by a xyloglucan polysaccharide derived from tamarind seed were evaluated as a sustained-release vehicle for the intraperitoneal administration of mitomycin C (MMC). The in vitro release of MMC from gels prepared from galactoxyloglucan that had been partially degraded by β -galactosidase to eliminate 44% of galactose residues followed root-time kinetics over 5 h. Intraperitoneal administration of MMC in a 1.5% (w/w) xyloglucan gel to rats resulted in a broad concentration–time profile for this drug in both the ascites and the plasma over a 3-h time period, compared with a narrow peak and rapid disappearance from both sites when this drug was given i.p. as a solution.

A fairly large amount of lysophosphatidylcholine (LPC) was detected in the fresh muscle of bonito Euthynnus pelamis (Linnaeus). The major fatty acid esterified in LPC were highly unsaturated fatty acids, such as docosahexaenoic and eicosapentaenoic acids, and the form was mainly composed of 1-lyso-2-acyl-sn-glycero-3-phosphocholine (1-LPC). The content of this species continued to increase during 4 months of frozen storage and then decreased. Phospholipase A1 activity detected in the bonito muscle was supposed to be responsible for the accumulation of LPC.

To clarify the mechanism underlying the ectopic excitation after countershock, the cellular activation processes of cardiac tissue with a low-potential-gradient electric field (LPEF) were investigated in experiments using guinea pig papillary muscles and in computer simulation. Action potential upstrokes in papillary muscles during longitudinal propagation (LP) or transverse propagation (TP) were different from those of nonpropagating ones in single ventricular cells in terms of lower maximum upstroke velocity (Vmax) (LP, 231 V/s; TP, 309 V/s) and the presence of a linear ascending segment in the phase-plane plot. High Vmax (409 V/s) close to the single cell (512 V/s) was obtained in the muscle at the collision of LP (LC). Field stimulation of the muscles with LPEF < 5 V/cm caused inhomogeneous excitation suggesting multiple wave fronts, which collide with each other, and a wide spatial dispersion of Vmax (132–388 V/s). Phase-plane plots of action potential with lower Vmax were similar to LP or TP, whereas those with higher Vmax were similar to LC. In the two-dimensional discrete sheet composed of 51 x 51 elements of modified Beeler-Reuter model, the inhomogeneous excitation induced by LPEF is mimicked by setting a random variation of stimulus onset in each element. LPEF may induce inhomogeneous excitation with multiple wave fronts through a complex electrotonic interaction. This would provide a basis for the genesis of ectopic focal excitation.

The specificity of the glycosaminoglycan (GAG) acceptor sites of ryudocan was examined by stably expressing epitope-tagged ryudocan cDNA constructs in mouse L cells, which normally produce this proteoglycan. Immunopurified ryudocan was glycanated with both heparan sulfate (HS) and chondroitin sulfate (CS). The attachment of GAGs to ryudocan was prevented by creating Ser-->Thr mutations in all possible combinations at positions 44, 65, and 67. The resulting ryudocan of exogenous origin was immunopurified and evaluated with regard to attached GAG chains. The data reveal that ryudocan possesses three functional GAG attachment sites, that the sites are always occupied with GAG chains, and that each site is capable of bearing either HS or CS. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis patterns of GAG lyase digests of intact ryudocan reveal the production of the following multiple isoforms: pure HS-ryudocan, various HS/CS-hybrids, and pure CS-ryudocan. The data suggest that the occupancy bias of each site for HS or CS is slight and that each site functions in a relatively independent fashion. The GAG lyase analysis of partially purified L cell proteoglycans shows two pure CS-homoglycans with core proteins of M(r) = 130,000 and 52,000, respectively. A similar analysis of immunopurified L cell glypican demonstrates that this species only exists as a pure HS-homoglycan. The production of pure homoglycans by this clonal cell line strongly suggests that the functional promiscuity of GAG attachment sites of ryudocan must be encoded in the core protein structure. This property of ryudocan is not peculiar to L cells, as ryudocan synthesized by early passage human endothelial cells also bears both HS and CS. The production of multiple isoforms of ryudocan may serve to expand the functional versatility of this cell surface component and allow it to participate in many different biologic processes.

Eugenol dose-dependently inhibited 5-HETE (5-hydroxy-5,8,10, 14-eicosatetraenoic acid) and 15-HETE formation by human polymorphonuclear leucocytes. p-Chlorophenol, guaiacol and phenol also inhibited the lipoxygenases. Formation of HETEs by rat dental pulp was inhibited by eugenol and p-chlorophenol. The concentrations of the phenolics required to inhibit lipoxygenases were in the similar range with those used for inhibiting cyclooxygenase. These results showed that phenolic compounds inhibited lipoxygenases and thus suggest that these compounds may be dual inhibitors of lipoxygenase and cyclooxygenase.

With the advent of drug eluting stents in percutaneous coronary intervention, required quality level of coronary artery bypass grafting (CABG) has been elevating. To obtain nearly perfect patency of bypass grafts, intraoperative assessment and repair of abnormal grafts are helpful. We report systematic revision and safe repair technique of arterial grafts in CABG. Side-to-side instead of commonly used end-to-side anastomosis of arterial grafts is the first step in this technique. When any abnormalities are noted in intraoperative flowmetry of a graft, the distal surgical clip is removed. Free flow of the graft is measured. A coronary probe is gently inserted into the graft and the coronary artery. Vasodilators can be injected into the graft if necessary. When direct revision of the anastomosis is indicated, the graft is cut longitudinally from the distal end up to just proximal to the anastomotic site. The shape of the anastomosis can be observed directly without removing sutures. When re-anastomosis is not indicated, the distal remnant graft tissue is folded back and utilized as a patch. Thus the graft can be easily closed without narrowing.

A revised model of sodium current which was structurally analogous to the Hodgkin and Huxley formulation was proposed to describe the rapid upstroke phase of the car- diac action potential quantitatively. The parameters of this IN^ model were estimated by using a nonlinear parameter estima- tion method to fit the action potential which was obtained in the normal physiological condition. To examine the model, the characteristics of IN* were compared to these of other known 1~~ models and recent voltage clamp experimental data. The present model could reproduce following experimental results: 1) voltage-dependence of availability for if,,, 2) the dynamic change of the action potential, 3) activation and inactivation ki- netics similar to sodium sodium currents at 37 C, 4) the peak sodium current-voltage voltage relationship.

Recently the availability of transit time flow measurement (TTFM) is reported especially in off-pump coronary artery bypass grafting (CABG). But little is known about TTFM findings in on-pump CABG. We examined the correlation between the TTFM flow pattern and the angiography findings in on-pump CABG. The subjects consisted of 52 patients who underwent on-pump CABG and angiography early after operation. In these patients, 55 internal thoracic artery (ITA), 17 gastroepiploic artery (GEA), 13 saphenous vein graft (SVG) and 41 radial artery (RA) were tested with TTFM during cardiopulmonary bypass (CPB). TTFM demonstrated a diastolic filling pattern in 53 ITA, 16 GEA, 13 SVG and 36 RA. The angiography revealed that all these grafts were perfectly patent with the exception of a GEA with a flow competition pattern. TTFM revealed an abnormal flow pattern in 2 ITA (these 2 grafts were revised during CPB and the angiography demonstrated their perfect patency), 1 GEA (to and fro pattern), 0 SVG and 5 RA (the abnormal pattern was due to graft spasm in 3 of 5, and the angiography revealed their perfect patency, however, the angiography detected stenosis in the remaining 2 grafts). The present study found that the TTFM flow pattern during CPB correlated well with the angiography findings. TTFM during CPB was useful to detect graft failure, and grafts were revised safely during CPB.

The aim of this research is to realize autonomous traffic management by using an adaptive routing control. In this paper, new router architecture is designed to the adaptive routing. In this technique, a router always supervises a traffic situation. Communication costs for every link are calculated based on the traffic situation. Scheduling of the transmitting route on the basis of the cost performs dynamic load distribution. The routers cooperate by the exchange of the control information added to the packet without preventing other communication in network. The adaptive routing control is performed autonomously. As the result, communication capacity is rearranged and connection situation is improved. Moreover, communication quality is improved by scheduling of transmission of packet. To evaluate the router and routing control software, simulation and its results are presented. Compared with routing via OSPF, this technique gives about 75% improvement of throughput in a LAN model.

A 3936/spl times/2196 pixel CMOS APS has a 10 b column-based ADC. It operates at 49.5 MHz in a progressive scanning mode at 60 frames/s and achieves a 2000 TV line resolution, sensitivity of 4200 b/lux-s, and power consumption of less than 760 mW.

The authors investigated the excitation process of the cardiac muscle under electrical field stimulation using guinea pig hearts and a mathematical model. Maximum upstroke velocity of action potentials elicited by the field stimulation had a wide range of value, and its mean value was about a half as high as that from the single ventriculocytes. The phase planes of upstrokes under the field stimulation were indistinguishable from those during propagation. These results indicate that the whole cardiac tissue does not excite homogeneously, and action potential propagation does occur within the tissue. A mathematical model analysis revealed that the diverse passive membrane property of each cell was able to reproduce the inhomogeneous excitation pattern similar to that observed experimentally. It is concluded that the diverse cell membrane properties have an important role in tissue excitation under field stimulation. >

Anisotropic propagation of cardiac action potential was studied using a two-dimensional hexagonal model which consists of single cells interconnected by gap junctional conduction (g/sub gap/) with the six neighbouring cells. To examine the structural difference between the models for propagation properties, a one-dimensional model and a two-dimensional lattice model were also constructed. They have two and four gap connections, respectively. The size of the single cell was assumed to be 0.12 mm in length and 0.03 mm in diameter. Membrane properties of the cell were described by a modified DiFrancesco-Noble model with a revised sodium current description. Values of G/sub gap/ of each propagation model were adjusted to yield the conduction velocities measured experimentally. It was found that the hexagonal model could qualitatively explain experimental observations about anisotropic propagation. It is concluded that model structure definitely affects the shape of the propagating action potential. >

This paper reports the angle of arrival (AOA) measurement error due to the coupling of an antenna which is used for the frequency close to that under the measurement. The coupling of sensors which is ignored in most cases of acoustic problems is one of the essential effects for electromagnetic measurements. An example of this phenomena is observed with the AOA subsystem of an airborne collision avoidance system (ACAS). Some onboard antennas are the error sources as the coupled scatterer to the AOA antenna. In this paper, the effect of the coupled scatterer on the airborne AOA antenna is discussed. The received signals of the antenna elements are calculated by solving the coupled antenna problem directly. The AOA error by the scatterer is estimated from these signals by assuming an AOA estimator. The AOA error is measured by anechoic chamber experiments. The relation between the AOA measurement error and the scatterer location is discussed. The signal processing method which can reduce the AOA error under the antenna coupling is needed for the improvements of ACAS.

The authors reevaluated the process of action potential propagation in a quantitative manner, using a spacially discrete cable model with an optimized membrane current model. The model reconstructs an action potential upstroke with a higher stroke velocity (V/sub max/) of 451 V/s, which was comparable to that obtained from isolated myocytes (512+or-77 V/s). The gap junctional conductance (G/sub j/) was estimated based upon the conduction velocity (65+or-6 cm/s) along the long axis of papillary muscles. The estimated G/sub j/ was 6 mS/cm/sup 2/, that is 700 nS, which was within the range of the measured gap conductances from paired ventriculocytes. In the one-dimensional model, the V/sub max/ of the simulated propagating action potential was 322 V/s, which was larger than the V/sub max/ obtained from papillary muscles ( theta /sub L/) (237+or-25 V/s) by approximately 35%. In the two-dimensional hexagonal model, the simulated theta /sub L/ was 63 cm/s and the V/sub max/ amounted to 257 V/s, which was comparable to the experimental results. >

A mathematical model was reconstructed based on the upstroke and sodium current separately recorded from enzymatically dispersed ventricular myocytes of a guinea pig, using the patch clamp technique. After holding the membrane potentials ranging from -120 to -60 mV for 500 ms, the upstroke was induced by applying the stimulus through the patch electrode with the constant latency to obtain voltage-dependence of availability for V/sub max/. Phase plane plots (membrane potential vs. dV/dt) were used for optimization of a mathematical model. Experimental results could be reproduced by the model. >

The international standards of airborne collision avoidance systems were approved by the ICAO. Since these systems use currently available technologies to prevent near mid-air collisions, they have a number of problems to be solved. To obtain quantitative measures of current systems performance, which are required to evaluate the system improvements, performance type standards are necessary. Since such standards are not available as main standards, modifications are discussed. The aircraft encounter model is one of the major part of these standards. This paper discusses the model of aircraft vertical profiles using the factor analysis method. It also discusses the mathematical model of the profiles.

This paper discusses the evaluation method of Airborne Collision Avoidance System (ACAS) algorithms. The risk ratio analysis is discussed using probability theory. Natural spline functions are presented as a tool for radar data smoothing and interpolation. Finally, the risk ratios of sample situations are calculated.

Publisher Summary Xyloglucan is a major structural polysaccharide in the primary cell walls of higher plants. Cell growth and enlargement are controlled by the looseness of a thin net of microfibrils made of cellulose. Xyloglucan cross-links these cellulose microfibrils and provides the flexibility necessary for the microfibrils to slide. Also, some of the xyloglucan oligosaccharides released by β -glucanase have biological functions and are capable of promoting growth of plant cells. As it has a β -1,4-glucan backbone, xyloglucan is not digested by human digestive enzymes and acts as a dietary fiber. This chapter describes the effects of tamarind xyloglucan on lipid metabolism in rats. Both intact xyloglucan and hydrolyzed xyloglucan reduce plasma and liver lipids in rats that are fed a high-cholesterol diet. Both also significantly reduce adipose tissue weight. Hydrolyzed xyloglucan reduces plasma and liver lipids in rats that are fed a high-fat diet. These results indicate that the intake of both intact and hydrolyzed xyloglucan improves lipid metabolism in rats. These hypolipidemic effects may be important for the treatment and prevention of geriatric diseases, including diabetes and cardiac disorders.

Multiprotein bridging factor 1 (MBF1) is a transcriptional coactivator that is thought to bridge between the TATA box-binding protein (TBP) and DNA binding regulatory factors, and is conserved from yeast to human. Human MBF1 (hMBF1) can bind to TBP and to the nuclear receptor Ad4BP, and is suggested to mediate Ad4BP-dependent transcriptional activation. Here we report the resonance assignments and secondary structure of hMBF1 (57-148) that contains both TBP binding and activator binding residues. 15N relaxation data were also obtained. As a result, hMBF1 (57-148) was shown to consist of flexible N-terminal residues and a C-terminal domain. The C-terminal domain contains four helices and a conserved C-terminal region.

Multiprotein bridging factor 1 (MBF1) is a transcriptional coactivator necessary for transcriptional activation caused by DNA binding activators, such as FTZ-F1 and GCN4. MBF1 bridges the DNA-binding regions of these activators and the TATA-box binding protein (TBP), suggesting that MBF1 functions by recruiting TBP to promoters where the activators are bound. In addition, MBF1 stimulates DNA binding activities of the activators to their recognition sites. To date, little is known about structures of coactivators that bind to TBP.The two-dimensional (2D) 1H-15N correlation spectrum of 15N labeled MBF1 indicated that MBF1 consists of both flexible and well structured parts. Limited digestion of MBF1 by alpha-chymotrypsin yielded a approximately 9 kDa fragment. N-terminal sequence analysis and NMR measurements revealed that this fragment originates from the C-terminal 80 residues of MBF1 and form a well structured C-terminal domain of MBF1, MBF1CTD. As previous deletion analyses have shown that MBF1CTD is capable of binding to TBP, it is suggested that MBF1CTD is the TBP binding domain of MBF1. Sequential assignments have been obtained by means of three-dimensional (3D) and four dimensional (4D) heteronuclear correlation spectroscopies, and then the secondary structure of MBF1CTD was determined. As a result, MBF1CTD was shown to contain four amphipathic helices and a conserved C-terminal region. Asp106 which is assumed to be responsible for the binding to TBP is located at the hydrophilic side of the third helix.Structural analyses revealed that MBF1 consists of two structurally different domains. A N-terminal region is indispensable for the binding to activators, and does not form a well defined structure. In contrast, the C-terminal 80 residues, which is capable of binding to TBP by itself, form a well-structured domain, MBF1CTD. MBF1CTD is made up of four amphipathic helices and a conserved C-terminal tail. A putative TBP binding residue is located on the hydrophilic surface of the third helix.

L cells and endothelial cells synthesize a heparan sulfate (HS) subpopulation, HSact, that exhibits anticoagulant activity due to a specific monosaccharide sequence; the remaining heparan sulfate, HSinact, lacks this region of defined structure and is anticoagulantly inactive. HSact biosynthesis was examined in these two cell types by stably expressing epitope-tagged rat ryudocan (ryudocan12CA5), which possesses three glycosaminoglycan (GAG) acceptor sites. Both HSact and HSinact were present on ryudocan12CA5 isolated from L cells and endothelial cells; thus, a core protein with a unique primary sequence initiates the synthesis of both GAGs. The expression in L cells of ryudocan12CA5 variants containing a single functional GAG acceptor site demonstrated that each of the three acceptor regions initiates the synthesis of both types of GAGs to a similar extent. Most importantly, in both cell types total HSact generation declined as a function of ryudocan12CA5 overexpression even though HSinact production increased linearly as a function of this variable. This discordant relationship is a general property of the biosynthetic machinery since in both cell types HSact production was reduced to an equal extent on protein cores of either exogenous or endogenous origins. The suppression of HSact generation was also observed with a secreted form of core protein lacking transmembrane and cytoplasmic domains or by a GAG acceptor site mutated form of core protein incapable of augmenting GAG synthesis. These results suggest that elevated intracellular levels of core protein saturate the capacity of a critical component of the HSact biosynthetic machinery. This critical component is not a member of the common set of biosynthetic enzymes involved in the production of HSact and HSinact since no structural changes were observed in either GAG during overexpression of core protein. Based upon the above data, we conclude that increased intracellular levels of ryudocan probably act by saturating the capacity of components which regulate HSact production by coordinating the function of biosynthetic enzymes.

The specificity of the glycosaminoglycan (GAG) acceptor sites of ryudocan was examined by stably expressing epitope-tagged ryudocan cDNA constructs in mouse L cells, which normally produce this proteoglycan. Immunopurified ryudocan was glycanated with both heparan sulfate (HS) and chondroitin sulfate (CS). The attachment of GAGs to ryudocan was prevented by creating Ser--Thr mutations in all possible combinations at positions 44, 65, and 67. The resulting ryudocan of exogenous origin was immunopurified and evaluated with regard to attached GAG chains. The data reveal that ryudocan possesses three functional GAG attachment sites, that the sites are always occupied with GAG chains, and that each site is capable of bearing either HS or CS. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis patterns of GAG lyase digests of intact ryudocan reveal the production of the following multiple isoforms: pure HS-ryudocan, various HS/CS-hybrids, and pure CS-ryudocan. The data suggest that the occupancy bias of each site for HS or CS is slight and that each site functions in a relatively independent fashion. The GAG lyase analysis of partially purified L cell proteoglycans shows two pure CS-homoglycans with core proteins of M(r) = 130,000 and 52,000, respectively. A similar analysis of immunopurified L cell glypican demonstrates that this species only exists as a pure HS-homoglycan. The production of pure homoglycans by this clonal cell line strongly suggests that the functional promiscuity of GAG attachment sites of ryudocan must be encoded in the core protein structure. This property of ryudocan is not peculiar to L cells, as ryudocan synthesized by early passage human endothelial cells also bears both HS and CS. The production of multiple isoforms of ryudocan may serve to expand the functional versatility of this cell surface component and allow it to participate in many different biologic processes.