bluuebunny/crossref_metadata_2025 huggingface dataset:
Nonlinear Model Predictive Control for the Swing-Up of a Rotary Inverted Pendulum
Authors: Jung Sooyong , Wen John T.
Published: December 2004

This paper presents the experimental implementation of a gradient-based nonlinear model predictive control (NMPC) algorithm to the swing-up control of a rotary inverted pendulum. The key attribute of the NMPC algorithm used here is that it only seeks to reduce the error at the end of the prediction horizon rather than finding the optimal solution. This reduces the computation load and allows real-time implementation. We discuss the implementation strategy and experimental results. In addition to NMPC based swing-up control, we also present results from a gradient based iterative learning control, which is the basis our NMPC algorithm.
Electromagnetic Coupling in a dc Motor and Tachometer Assembly
Authors: Awtar Shorya , Craig Kevin C.
Published: December 2004

This paper presents an enhanced tachometer model that takes into account the effect of electromagnetic coupling that can exist between the actuator and sensor in an integrated dc motor-tachometer assembly, where the conventional model is found to be inadequate. The tachometer dynamics identified in this paper is experimentally verified, and incorporated in the modeling and parameter identification of a motion system that has multiple flexible elements. It is shown that the tachometer dynamics contributes additional nonminimum phase zeros that degrade the servo system performance in terms of closed-loop bandwidth, disturbance rejection and sensitivity to modeling uncertainty. The zeros of the open loop system are found to vary with the geometric parameters of the motor-tachometer assembly. Based on the insight gained by modeling the electromagnetic coupling, methods for eliminating it and its resulting detrimental effects are also suggested.
Algorithm for Calculating MIMO QFT Tracking Bounds
Authors: Boje Edward
Published: December 2004

An algorithm for calculating design bounds in multivariable quantitative feedback theory (QFT) tracking design is presented. The algorithm solves the problem of trade-off between on- and off-diagonal constraints.
Simulation of a Mortar Launched, Parachute Deployed Battlefield Imaging System
Authors: Frost Geoffrey , Costello Mark
Published: December 2004

Flight behavior of a mortar launched, parachute deployed imaging system is examined with particular attention to characterizing the quantity and quality of recorded image data. Coverage area of the imager, blur due to motion of the imager, and view time are evaluated for different system configurations allowing important design parameters to be identified. It is shown that proper tailoring of the dynamic characteristics of the system greatly improves gathered image data quantity and quality. Coning of the canister is an important system characteristic that largely drives total ground coverage. Canister coning is influenced in a complex manner by system geometric parameters. Mounting the parachute riser to the canister in such a way that the connection is off the axis of symmetry of the canister is a powerful technique to increase coning of the canister. Likewise, increasing riser length also yields increased coning. Increasing spin rate of the canister leads to a proportional increase in image blur, which is largest toward the edge of the image. Also, increased canister weight tends to increase the descent rate, which reduces total view time. At the same time, increased descent rate increases the spin rate for cross type parachutes, leading to increased image blur.
Flight Dynamic Response of Spinning Projectiles to Lateral Impulsive Loads
Authors: Cooper G. R. , Costello Mark
Published: December 2004

The linear theory for spinning projectiles is extended to account for the application of a simple lateral square impulse activated during free flight. Analytical results are shown to produce simple contributions to the familiar aerodynamic jump formulation. Inquiries regarding jump smearing caused by nonzero impulse length are addressed and answered. The formulation shows for sufficiently long-term target interception, lateral impulse trajectory response for a guided projectile is independent of when the impulse is activated during the yaw cycle. Simple limits show the presented results reducing to those previously found for a zero-spin projectile acted upon by a singular lateral impulse.
Stability Analysis for a Class of Singularly Perturbed Systems With Multiple Time Delays
Authors: Pan Shing-Tai , Chen Ching-Fa , Hsieh Jer-Guang
Published: December 2004

The paper is to investigate the asymptotic stability for a general class of linear time-invariant singularly perturbed systems with multiple non-commensurate time delays. It is a common practice to investigate the asymptotic stability of the original system by establishing that of its slow subsystem and fast subsystem. A frequency-domain approach is first presented to determine a sufficient condition for the asymptotic stability of the slow subsystem (reduced-order model), which is a singular system with multiple time delays, and the fast subsystem. Two delay-dependent criteria, ε-dependent and ε-independent, are then proposed in terms of the H∞-norm for the asymptotic stability of the original system. Furthermore, a simple estimate of an upper bound ε* of singular perturbation parameter ε is proposed so that the original system is asymptotically stable for any ε∈0,ε*. Two numerical examples are provided to illustrate the use of our main results.
Escape of Intracellular
Shigella
from Autophagy
Authors: Ogawa Michinaga , Yoshimori Tamotsu , Suzuki Toshihiko , Sagara Hiroshi , Mizushima Noboru , Sasakawa Chihiro
Published: December 2004

The degradation of undesirable cellular components or organelles, including invading microbes, by autophagy is crucial for cell survival. Here,
Shigella
, an invasive bacteria, was found to be able to escape autophagy by secreting IcsB by means of the type III secretion system. Mutant bacteria lacking IcsB were trapped by autophagy during multiplication within the host cells. IcsB did not directly inhibit autophagy. Rather,
Shigella
VirG, a protein required for intracellular actin-based motility, induced autophagy by binding to the autophagy protein, Atg5. In nonmutant
Shigella
, this binding is competitively inhibited by IcsB binding to VirG.
Rofecoxib versus ibuprofen for acute treatment of migraine: a randomised placebo controlled trial
Authors: Misra U K , Jose M , Kalita J
Published: December 2004

Background: Rofecoxib is a potent cyclo-oxygenase-2 inhibitor with a long duration of action. Its role in migraine has not been systematically evaluated.

Aim: To study the efficacy of rofecoxib in migraine.

Method: In a randomised placebo controlled trial rofecoxib 25 mg, ibuprofen 400 mg, and placebo were compared regarding their efficacy in relieving acute migraine attack. Migraine patients with 2–6 attacks per month were recruited. Headache severity, functional disability, and severity of associated symptoms were graded on a 0–3 scale. The primary endpoint was pain relief at two hours. Relief of associated symptoms and sustained pain relief for 24 hours were also noted.

Result: One hundred and twenty four patients were randomised into rofecoxib (42), ibuprofen (40), and placebo (42) groups. One hundred and one patients were followed up: 33 on rofecoxib, 35 ibuprofen, and 33 placebo. Patients’ ages ranged from 16–62 (mean 31.4) years, and 83 were females. Pain relief at two hours was noted in 45.5% on rofecoxib, 55.6% on ibuprofen, and 9.1% in the placebo group. The associated symptoms at two hours were reduced in 39.4% on rofecoxib, 50% on ibuprofen, and 9.1% in the placebo group. Sustained 24 hour pain relief was noted in 36.4% on rofecoxib, 41% on ibuprofen, and 6.1% in the placebo group. In the ibuprofen group, five patients had abdominal pain but there were no side effects in those on rofecoxib or in the control group. Both rofecoxib and ibuprofen were significantly effective in relieving pain, associated symptoms at two hours, and in sustained pain relief. There was no significant difference between rofecoxib and ibuprofen in aborting acute migraine attacks.

Conclusions: Both ibuprofen and rofecoxib were superior to placebo in aborting an acute migraine attack, and there was no significant difference in their efficacy in an acute migraine attack.
Eosinophilia and symptomatic pulmonary amyloidosis
Authors: Haydar A A , Li A , Hilton R , Lams B , Hangartner R , Weber M , Goldsmith D J A
Published: December 2004

The case of a man with progressive breathlessness and pulmonary infiltration caused by AL amyloidosis associated with multiple myeloma is presented. There was a marked peripheral eosinophilia, which has not previously been described with amyloidosis.
Neurotological status in Behçet’s disease and its ophthalmological correlates
Authors: Bayazıt Y A , Evereklioğlu C , Ozer E , Kırtak N , Bayazıt N , Kanlıkama M , İnalöz S
Published: December 2004

Objective: To assess neurotological status and its ophthalmological correlates in Behçet’s disease.

Study design: A cross sectional study in which 17 patients with Behçet’s disease and 13 healthy controls were included.

Patients and methods: The patients were divided into two groups: those with and without end stage ocular involvement. Neurotological status was evaluated with audiological tests (pure tone and speech audiometry, tympanometry, short increment sensitivity index, tone decay, and evoked response audiometry), and Dix-Halpike positional testing.

Results: The positional test was normal. The audiological test results of the patients with and without end stage ocular involvement were not significantly different (p>0.05). A sloping audiogram with bilateral symmetric and mild sensorineural hearing loss was the main audiogram obtained. There was no relationship between the presence or absence of the end stage ocular involvement and the otological parameters studied excluding I–III interval on evoked response audiometry (p>0.05).

Conclusion: Although the main underlying pathogenetic factor in Behçet’s disease is the autoimmune vasculitis, the mechanisms involved in the pathogenesis of neurological and ocular damage may be different. Alternatively, the differential involvement of certain organ systems may not reflect the nature of the disease process itself, but rather the manner in which each organ responds to injury.
Nodules of fibrocollagenous scar tissue induced by subcutaneous insulin injections: a cause of poor diabetic control
Authors: Wallymahmed M E , Littler P , Clegg C , Haqqani M T , MacFarlane I A
Published: December 2004

A 46 year old man with longstanding type 1 diabetes developed major weight loss and marked deterioration in diabetic control. He had been persistently injecting insulin into areas of abdominal lipohypertrophy within which hard collagenised fibrous tissue nodules had developed. Injecting insulin at different sites dramatically improved blood glucose control. Fibrocollagenous nodules induced by insulin injections have not been previously described. Examination of a further 73 type 1 patients revealed lipohypertrophy in 44% and hard subcutaneous nodules on two.
QUANTIZATION OF A MODULI SPACE OF PARABOLIC HIGGS BUNDLES
Authors: BISWAS INDRANIL , MUKHERJEE AVIJIT
Published: December 2004

Let [Formula: see text] be a moduli space of stable parabolic Higgs bundles of rank two over a Riemann surface X. It is a smooth variety defined over [Formula: see text] equipped with a holomorphic symplectic form. Fix a projective structure [Formula: see text] on X. Using [Formula: see text], we construct a quantization of a certain Zariski open dense subset of the symplectic variety [Formula: see text].
ASYMPTOTIC CHOW SEMI-STABILITY AND INTEGRAL INVARIANTS
Authors: FUTAKI AKITO
Published: December 2004

We define a family of integral invariants containing those which are closely related to asymptotic Chow semi-stability of polarized manifolds. It also contains an obstruction to the existence of Kähler–Einstein metrics and its natural extensions by the author, Calabi and Bando as Kählerian invariants and by Morita and the author as invariant polynomials of the automorphism groups of compact complex manifolds.
HOMOLOGICAL INDEX FOR 1-FORMS AND A MILNOR NUMBER FOR ISOLATED SINGULARITIES
Authors: EBELING W. , GUSEIN-ZADE S. M. , SEADE J.
Published: December 2004

We introduce a notion of a homological index of a holomorphic 1-form on a germ of a complex analytic variety with an isolated singularity, inspired by Gómez-Mont and Greuel. For isolated complete intersection singularities it coincides with the index defined earlier by two of the authors. Subtracting from this index another one, called radial, we get an invariant of the singularity which does not depend on the 1-form. For isolated complete intersection singularities this invariant coincides with the Milnor number. We compute this invariant for arbitrary curve singularities and compare it with the Milnor number introduced by Buchweitz and Greuel for such singularities.
DISCONTINUOUS GALERKIN METHODS FOR FIRST-ORDER HYPERBOLIC PROBLEMS
Authors: BREZZI F. , MARINI L. D. , SÜLI E.
Published: December 2004

The main aim of this paper is to highlight that, when dealing with DG methods for linear hyperbolic equations or advection-dominated equations, it is much more convenient to write the upwind numerical flux as the sum of the usual (symmetric) average and a jump penalty. The equivalence of the two ways of writing is certainly well known (see e.g. Ref. 4); yet, it is very widespread not to consider upwinding, for DG methods, as a stabilization procedure, and too often in the literature the upwind form is preferred in proofs. Here, we wish to underline the fact that the combined use of the formalism of Ref. 3 and the jump formulation of upwind terms has several advantages. One of them is, in general, to provide a simpler and more elegant way of proving stability. The second advantage is that the calibration of the penalty parameter to be used in the jump term is left to the user (who can think of taking advantage of this added freedom), and the third is that, if a diffusive term is present, the two jump stabilizations (for the generalized upwinding and for the DG treatment of the diffusive term) are often of identical or very similar form, and this can also be turned to the user's advantage.
SHILL BIDDING IN ONLINE ENGLISH AUCTIONS WITH A RANDOM NUMBER OF BIDDERS
Authors: MA JUN , WANG SHOUYANG , LAI K. K.
Published: December 2004

Shill bidding has increased substantially with the explosion in the number of online auctions. For English auctions with conventional intermediation fee schedules and a continuous increment of the bid, sellers may profit from shill bidding, which is illegal. To deter shill bidding, Wang et al.31 designed a mechanism — the shill-deterrent fee schedule (SDFS) which makes shill bidding unprofitable. This paper analyzes the feasibility of applying SDFS rules to both single round and multi-round English auctions in a framework of independent private value (IPV) with a random number of bidders. It is shown that most of the results in Wang et al.31 remain true at our cases. In addition, we also propose an approach for sellers to reset the subsequent reserves in multi-round English auctions.
E-SUPPLY CHAIN IMPLEMENTATION STRATEGIES IN A TRANSITIONAL ECONOMY
Authors: CHEN L. , LONG J. , YAN T.
Published: December 2004

Competing in today's environment is to compete between supply chains. Organizations strive for lower costs and respond rapidly to changes in the market. E-supply chain is one of the current approaches for achieving competitive advantages. Panta et al., developed a framework of evaluating e-supply chain implementation strategies for a free market economy with two factors.24 However, implementing e-supply chains in a transitional economy is subject to additional constraints in comparison with a free market economy. Information asymmetry and government influence are the two distinguished factors on the e-supply chain implementation strategies in transitional economy. This paper extends the framework of e-supply chain implementation strategies to include the above two factors. This new framework divides the whole problem space into seven cases. An implementation strategy is proposed for each case.
UNIVERSALLY COMPOSABLE BLIND SIGNATURE FUNCTIONALITY
Authors: CHEUNG SHIRLEY H. C. , LEE C. H. , ZHAO YUNLEI
Published: December 2004

Blind signatures play a critical role in digital cash systems. In this paper, we investigate the blind signature functionality in the framework of universally composable (UC) security — the strongest security guarantees up to now for cryptographic protocols over the Internet. We present the universally composable blind signature functionality, [Formula: see text]. Our approach is based on a new UC signature functionality [Formula: see text], which is a modified version of the original signature functionality [Formula: see text] presented by Canetti. We also prove that [Formula: see text] and [Formula: see text] are actually equivalent with respect to non-adaptive adversaries. Our result is of both theoretical and practical consequence to future research studies and practical implementations of digital cash systems with universally composable security.
DISCOVERY OF FUNCTIONAL GENES FOR SYSTEMIC ACQUIRED RESISTANCE INARABIDOPSIS THALIANATHROUGH INTEGRATED DATA MINING
Authors: PAN YOULIAN , PYLATUIK JEFFREY D. , OUYANG JUNJUN , FAMILI A. FAZEL , FOBERT PIERRE R.
Published: December 2004

Various data mining techniques combined with sequence motif information in the promoter region of genes were applied to discover functional genes that are involved in the defense mechanism of systemic acquired resistance (SAR) in Arabidopsis thaliana. A series of K-Means clustering with difference-in-shape as distance measure was initially applied. A stability measure was used to validate this clustering process. A decision tree algorithm with the discover-and-mask technique was used to identify a group of most informative genes. Appearance and abundance of various transcription factor binding sites in the promoter region of the genes were studied. Through the combination of these techniques, we were able to identify 24 candidate genes involved in the SAR defense mechanism. The candidate genes fell into 2 highly resolved categories, each category showing significantly unique profiles of regulatory elements in their promoter regions. This study demonstrates the strength of such integration methods and suggests a broader application of this approach.
LOCAL SEQUENCE-STRUCTURE MOTIFS IN RNA
Authors: BACKOFEN ROLF , WILL SEBASTIAN
Published: December 2004

Ribonuclic acid (RNA) enjoys increasing interest in molecular biology; despite this interest fundamental algorithms are lacking, e.g. for identifying local motifs. As proteins, RNA molecules have a distinctive structure. Therefore, in addition to sequence information, structure plays an important part in assessing the similarity of RNAs. Furthermore, common sequence-structure features in two or several RNA molecules are often only spatially local, where possibly large parts of the molecules are dissimilar. Consequently, we address the problem of comparing RNA molecules by computing an optimal local alignment with respect to sequence and structure information. While local alignment is superior to global alignment for identifying local similarities, no general local sequence-structure alignment algorithms are currently known. We suggest a new general definition of locality for sequence-structure alignments that is biologically motivated and efficiently tractable. To show the former, we discuss locality of RNA and prove that the defined locality means connectivity by atomic and non-atomic bonds. To show the latter, we present an efficient algorithm for the newly defined pairwise local sequence-structure alignment (lssa) problem for RNA. For molecules of lengthes n and m, the algorithm has worst-case time complexity of O(n2·m2· max (n,m)) and a space complexity of only O(n·m). An implementation of our algorithm is available at . Its runtime is competitive with global sequence-structure alignment.
PAIRWISE PROTEIN STRUCTURE ALIGNMENT BASED ON AN ORIENTATION-INDEPENDENT BACKBONE REPRESENTATION
Authors: YE JIEPING , JANARDAN RAVI , LIU SONGTAO
Published: December 2004

Determining structural similarities between proteins is an important problem since it can help identify functional and evolutionary relationships. In this paper, an algorithm is proposed to align two protein structures. Given the protein backbones, the algorithm finds a rigid motion of one backbone onto the other such that large substructures are matched. The algorithm uses a representation of the backbones that is independent of their relative orientations in space and applies dynamic programming to this representation to compute an initial alignment, which is then refined iteratively. Experiments indicate that the algorithm is competitive with two well-known algorithms, namely DALI and LOCK.
Expression of the ammonia transporter proteins Rh B glycoprotein and Rh C glycoprotein in the intestinal tract
Authors: Handlogten Mary E. , Hong Seong-Pyo , Zhang Li , Vander Allen W. , Steinbaum Marshall L. , Campbell-Thompson Martha , Weiner I. David
Published: December 2004

Ammonia metabolism is important in multiple aspects of gastrointestinal physiology, but the mechanisms of ammonia transport in the gastrointestinal tract remain incompletely defined. The present study examines expression of the ammonia transporter family members Rh B glycoprotein (RhBG) and Rh C glycoprotein (RhCG) in the mouse gastrointestinal tract. Real-time RT-PCR amplification and immunoblot analysis identified mRNA and protein for both RhBG and RhCG were expressed in stomach, duodenum, jejunum, ileum, and colon. Immunohistochemistry showed organ and cell-specific expression of both RhBG and RhCG. In the stomach, both RhBG and RhCG were expressed in the fundus and forestomach, but not in the antrum. In the forestomach, RhBG was expressed by all nucleated squamous epithelial cells, whereas RhCG was expressed only in the stratum germinativum. In the fundus, RhBG and RhCG immunoreactivity was present in zymogenic cells but not in parietal or mucous cells. Furthermore, zymogenic cell RhBG and RhCG expression was polarized, with apical RhCG and basolateral RhBG immunoreactivity. In the duodenum, jejunum, ileum, and colon, RhBG and RhCG immunoreactivity was present in villous, but not in mucous or crypt cells. Similar to the fundic zymogenic cell, RhBG and RhCG expression in villous epithelial cells was polarized when apical RhCG and basolateral RhBG immunoreactivity was present. Thus the ammonia transporting proteins RhBG and RhCG exhibit cell-specific, axially heterogeneous, and polarized expression in the intestinal tract suggesting they function cooperatively to mediate gastrointestinal tract ammonia transport.
Evidence for a functional calcium-sensing receptor that modulates myogenic tone in rat subcutaneous small arteries
Authors: Ohanian Jacqueline , Gatfield Kelly M. , Ward Donald T. , Ohanian Vasken
Published: December 2004

Myogenic tone of small arteries is dependent on the presence of extracellular calcium ([Formula: see text]), and, recently, a receptor that senses changes in Ca2+, the calcium-sensing receptor (CaR), has been detected in vascular tissue. We investigated whether the CaR is involved in the regulation of myogenic tone in rat subcutaneous small arteries. Immunoblot analysis using a monoclonal antibody against the CaR demonstrated its presence in rat subcutaneous arteries. To determine whether the CaR was functionally active, segments of artery (<250 μm internal diameter) mounted in a pressure myograph with an intraluminal pressure of 70 mmHg were studied after the development of myogenic tone. Increasing [Formula: see text] concentration ([Ca2+]o) cumulatively from 0.5 to 10 mM induced an initial constriction (0.5–2 mM) followed by dilation (42 ± 5% loss of tone). The dose-dependent dilation was mimicked by other known CaR agonists including magnesium (1–10 mM) and the aminoglycosides neomycin (0.003–10 mM) and kanamycin (0.003–3 mM). PKC activation with the phorbol ester phorbol-12,13-dibutyrate (20nM) inhibited the dilation induced by high [Ca2+]oor neomycin, whereas inhibition of PKC with GF109203X (10 μM) increased the responses to [Formula: see text] or neomycin, consistent with the role of PKC as a negative regulator of the CaR. We conclude that rat subcutaneous arteries express a functionally active CaR that may be involved in the modulation of myogenic tone and hence the regulation of peripheral vascular resistance.
Effects of tetraiodothyronine and triiodothyronine on hamster cheek pouch microcirculation
Authors: Colantuoni A. , Marchiafava P. L. , Lapi D. , Forini F. S. , Iervasi G.
Published: December 2004

The aim of the present study was to assess the effects of topically applied triiodothyronine (T3) and thyroxine (T4) on the arterioles of hamster cheek pouch microcirculation in vivo. Microvessels were visualized using a fluorescent microscopy technique. Topical application of T3(3.08, 30.8, 61.5, 307, 615, and 6,150 nM/l) consistently induced dose-dependent dilation of arterioles within 2.0 ± 0.5 min of administration. The application of T4(150, 257, 514, and 5,140 nM/l) caused different dose-dependent effects: dilation at the three lower doses within 16 ± 2 min and rhythmic diameter changes at the highest dose. Aging of hamsters did not alter the arteriolar responses to T3and T4. T3-induced dilation was countered by the inhibition of nitric oxide synthase with NG-nitro-l-arginine-methyl ester or NG-nitro-l-arginine. Iopanoic acid (IPA), which inhibits types I and II 5′-deiodinase, abolished the dilation elicited by 514 nM T4but did not affect T3-dependent dilation. 6-Propyl-2-thiouracil (PTU), which inhibits type I 5′-deiodinase only, did not affect the dilation induced by T4. IPA and PTU did not impair arteriolar dilation induced by acetylcholine or sodium nitroprusside. These results indicate that T3induces arteriolar dilation, likely through nitric oxide release. The local conversion of T4to T3appears to be crucial for the dilation induced by T4.
Sarcoplasmic reticulum Ca2+ transport and gene expression in congestive heart failure are modified by imidapril treatment
Authors: Shao Qiming , Ren Bin , Saini Harjot K. , Netticadan Thomas , Takeda Nobuakira , Dhalla Naranjan S.
Published: December 2004

This study was designed to test the hypothesis that blockade of the renin-angiotensin system improves cardiac function in congestive heart failure by preventing changes in gene expression of sarcoplasmic reticulum (SR) proteins. We employed rats with myocardial infarction (MI) to examine effects of an angiotensin-converting enzyme inhibitor, imidapril, on SR Ca2+ transport, protein content, and gene expression. Imidapril (1 mg·kg−1·day−1) was given for 4 wk starting 3 wk after coronary artery occlusion. Infarcted rats exhibited a fourfold increase in left ventricular end-diastolic pressure, whereas rates of pressure development and decay were decreased by 60 and 55%, respectively. SR Ca2+ uptake and Ca2+ pump ATPase, as well as Ca2+ release and ryanodine receptor binding activities, were depressed in the failing hearts; protein content and mRNA levels for Ca2+ pump ATPase, phospholamban, and ryanodine receptor were also decreased by ∼55–65%. Imidapril treatment of infarcted animals improved cardiac performance and attenuated alterations in SR Ca2+ pump and Ca2+ release activities. Changes in protein content and mRNA levels for SR Ca2+ pump ATPase, phospholamban, and ryanodine receptor were also prevented by imidapril treatment. Beneficial effects of imidapril on cardiac function and SR Ca2+ transport were not only seen at different intervals of MI but were also simulated by another angiotensin-converting enzyme inhibitor, enalapril, and an ANG II receptor antagonist, losartan. These results suggest that blockade of the renin-angiotensin system may increase the abundance of mRNA for SR proteins and, thus, may prevent the depression in SR Ca2+ transport and improve cardiac function in congestive heart failure due to MI.
Regional myocardial perfusion under exchange transfusion with liposomal hemoglobin: in vivo and in vitro studies using rat hearts
Authors: Matsumoto T. , Asano T. , Mano K. , Tachibana H. , Todoh M. , Tanaka M. , Kajiya F.
Published: December 2004

The purpose of this study was to test the hypothesis that exchange transfusion with liposomal hemoglobin (LH) reduces the microheterogeneity of regional myocardial flows while sustaining cardiac function. Neo Red Cell mixed with albumin was used as the LH solution, in which the LH volume fraction was 17∼18% and hemoglobin density was nearly two-thirds smaller than in rat blood. Regional myocardial flows in left ventricular free walls were measured by tracer digitalradiography (100-μm resolution) in anesthetized rats with or without 50% blood-LH exchange transfusion. Within-layer flow distributions showed lower heterogeneity with ( n = 8) than without ( n = 8) LH transfusion. No extravasation of hemoglobin was confirmed by 3,3-diaminobenzidin staining ( n = 2). Carotid flow increased by 68% due to LH transfusion, whereas arterial pressure and heart rate remained unchanged. On the other hand, cross-circulated rat hearts ( n = 7) were used to evaluate the effects of 50% blood-LH exchange on coronary flow and tone preservation under 300-beats/min pacing and 100-mmHg perfusion pressure. Blood-LH exchange caused a 71% increase of coronary flow and 10% decrease of percent flow increase during hyperemia after 30-s flow interruption. Myocardial O2 supply and consumption increased by 9% and 10%, respectively, whereas myocardial O2 extraction remained unchanged. The large increases of in vivo carotid flow and coronary flow in cross-circulated hearts due to LH coperfusion could be explained by the reduction of apparent flow viscosity. These results suggest that under LH coperfusion, the microheterogeneity of myocardial flows decreases with increased coronary flow while fairly preserving coronary tone and cardiac function.
Resistance artery vasodilation to magnesium sulfate during pregnancy and the postpartum state
Authors: Euser Anna G. , Cipolla Marilyn J.
Published: December 2004

This study compared the vasodilatory responses to magnesium sulfate (MgSO4) of cerebral and mesenteric resistance arteries and determined whether the responses varied between different gestational groups. Third-order branches (<200 μm) of the posterior cerebral (PCA) and mesenteric arteries (MA) were dissected from nonpregnant (NP; n = 6), late pregnant (LP; day 19, n = 6), and postpartum (PP; day 3, n = 6) Sprague-Dawley rats. A concentration-response curve was performed by replacing the low-MgSO4 (1.2 mM) HEPES buffer solution with increasing concentrations of MgSO4 (4, 6, 8, 16, and 32 mM) and measuring lumen diameter at each concentration. All groups exhibited concentration-dependent dilation to MgSO4, decreasing the amount of tone in the vessels. However, MA were significantly more sensitive to MgSO4 than PCA. Whereas there was no difference in the response between different gestational groups in MA, the PCA from the LP and PP groups showed a significantly diminished response to MgSO4. The percent dilation at 32 mM MgSO4 for PCA versus MA in NP, LP, and PP animals was 36 ± 2 vs. 51 ± 7% ( P < 0.05), 19 ± 9 vs. 54 ± 6% ( P < 0.01 vs. PCA and NP), and 12 ± 5 vs. 52 ± 11% ( P < 0.01 vs. PCA and NP). These results demonstrate that MgSO4 is a vasodilator of small resistance arteries in the cerebral and mesenteric vascular beds. The refractory responses of the PCA in LP and PP groups demonstrate changes in the cerebrovascular vasodilatory mechanisms with gestation. The greater sensitivity of the MA to MgSO4-induced vasodilation suggests that the prophylactic effect of MgSO4 on eclamptic seizures may be more closely related to the lowering of systemic blood pressure than to an effect on cerebral blood flow.
Essential role of protein kinase G and decreased cytoplasmic Ca2+levels in NO-induced inhibition of rat aortic smooth muscle cell motility
Authors: Zhuang Daming , Ceacareanu Alice-Corina , Ceacareanu Bogdan , Hassid Aviv
Published: December 2004

Hyperinsulinemia is a major risk factor for the development of vascular disease. We have reported that insulin increases the motility of vascular smooth muscle cells via a hydrogen peroxide-mediated mechanism and that nitric oxide (NO) attenuates insulin-induced motility via a cGMP-mediated mechanism. Events downstream of cGMP elevation have not yet been investigated. The aim of our study was to test the hypothesis that antimotogenic effects of NO and cGMP in cultured rat aortic smooth muscle cells are mediated via PKG, followed by reduction of cytoplasmic Ca2+levels and increased protein tyrosine phosphatase-proline, glutamate, serine, and threonine activity, leading to suppression of agonist-induced elevation of hydrogen peroxide levels and cell motility. Treatment of primary cultures with adenovirus expressing PKG-1α mimicked NO-induced inhibition of insulin-elicited hydrogen peroxide elevation and cell motility, whereas treatment with the pharmacological PKG inhibitor Rp-8-bromo-3′,5′-cyclic monophosphorothioate (Rp-8-Br-cGMPS) rescued the stimulatory effects of insulin that were suppressed by NO donor. Treatment of cells with insulin failed to increase cytoplasmic Ca2+levels, whereas NO donor decreased cytoplasmic Ca2+levels in the presence or absence of insulin. Treatment of cells with the Ca2+chelator BAPTA mimicked the effects of PKG and the NO donor and increased the activity of PTP-PEST. Finally, treatment with a dominant negative allele of PTP-PEST reversed the inhibitory effect of BAPTA on cell motility and hydrogen peroxide elevation. We conclude that NO-induced inhibition of cell motility occurs via PKG-mediated reduction of basal cytoplasmic Ca2+levels, followed by increased PTP-PEST activity, leading to decreased hydrogen peroxide levels and reduced cell motility.
N-methyl-d-aspartate receptor activation in human cerebral endothelium promotes intracellular oxidant stress
Authors: Sharp Christopher D. , Houghton J. , Elrod J. W. , Warren A. , Jackson T. H. , Jawahar A. , Nanda A. , Minagar A. , Alexander J. S.
Published: December 2004

Cerebral endothelial cells in the rat, pig, and, most recently, human have been shown to express several types of receptors specific for glutamate. High levels of glutamate disrupt the cerebral endothelial barrier via activation of N-methyl-d-aspartate (NMDA) receptors. We have previously suggested that this glutamate-induced barrier dysfunction was oxidant dependent. Here, we provide evidence that human cerebral endothelial cells respond to glutamate by generating an intracellular oxidant stress via NMDA receptor activation. Cerebral endothelial cells loaded with the oxidant-sensitive probe dihydrorhodamine were used to measure intracellular reactive oxygen species (ROS) formation in response to glutamate receptor agonists, antagonists, and second message blockers. Glutamate (1 mM) significantly increased ROS formation compared with sham controls (30 min). This ROS response was significantly reduced by 1) MK-801, a noncompetitive NMDA receptor antagonist; 2) 8-( N, N-diethylamino)- n-octyl-3,4,5-trimethoxybenzoate, an intracellular Ca2+antagonist; 3) LaCl3, an extracellular Ca2+channel blocker; 4) diphenyleiodonium, a heme-ferryl-containing protein inhibitor; 5) itraconazole, a cytochrome P-450 3A4 inhibitor; and 6) cyclosporine A, which prevents mitochondrial membrane pore transition required for mitochondrial-dependent ROS generation. Our results suggest that the cerebral endothelial barrier dysfunction seen in response to glutamate is Ca2+dependent and may require several intracellular signaling events mediated by oxidants derived from reduced nicotinamide adenine dinucleotide oxidase, cytochrome P-450, and the mitochondria.
Genetic Diversity of Hepatitis B Virus Strains Derived Worldwide: Genotypes, Subgenotypes, and HBsAg Subtypes
Authors: Norder Helene , Couroucé Anne-Marie , Coursaget Pierre , Echevarria José M. , Lee Shou-Dong , Mushahwar Isa K. , Robertson Betty H. , Locarnini Stephen , Magnius Lars O.
Published: December 2004

Sequences of 234 complete genomes and 631 hepatitis B surface antigen genes were used to assess the worldwide diversity of hepatitis B virus (HBV). Apart from the described two subgenotypes each for A and F, also B, C, and D divided into four subgenotypes each in the analysis of complete genomes supported by significant bootstrap values. The subgenotypes of B and C differed in their geographical distribution, with B1 dominating in Japan, B2 in China and Vietnam, B3 confined to Indonesia, and B4 confined to Vietnam, all strains specifying subtype ayw1. Subgenotype C1 was common in Japan, Korea, and China; C2 in China, South-East Asia, and Bangladesh, and C3 in the Oceania comprising strains specifying adrq–, and C4 specifying ayw3 is encountered in Aborigines from Australia. This pattern of defined geographical distribution was less evident for D1–D4, where the subgenotypes were widely spread in Europe, Africa, and Asia, possibly due to their divergence having occurred a longer time ago than for genotypes B and C, with D4 being the first split and still the dominating subgenotype of D in the Oceania. The genetic diversity of HBV and the geographical distribution of its subgenotypes provide a tool to reconstruct the evolutionary history of HBV and may help to complement genetic data in the understanding of the evolution and past migrations of man.
Intracellular Expression Patterns of the Human Papillomavirus Type 59 E1^E4 Protein in COS Cells, Keratinocytes, and Genital Epithelium
Authors: Brown Darron R. , Brown Calla R. , Lehr Elizabeth E.
Published: December 2004

Objective: To compare and contrast the intracellular distribution pattern of the human papillomavirus type 59 (HPV 59) E1^E4 protein in COS cells, human keratinocytes, and naturally infected genital epithelium. Methods: The HPV 59 E1^E4 protein was expressed in COS cells and NIKS cells (immortalized human keratinocytes). A subset of NIKS cells was induced to differentiate. The intracellular distribution pattern of E1^E4 and the effects of E1^E4 expression on the cytoskeleton network were compared for COS and NIKS cells. Expression of E1^E4 was examined in HPV 59-infected foreskin xenografts grown in athymic mice and in a natural HPV 59-infected genital lesion. Results: The HPV 59 E1^E4 protein formed dense perinuclear inclusions in COS cells, similar to those reported for the HPV 16 E1^E4 protein. In contrast, the E1^E4 protein was diffusely cytoplasmic in undifferentiated NIKS cells, co-localizing with an intact cytokeratin filament network. The E1^E4 protein was concentrated in the region of the cornified cell envelope (CCE) of differentiated NIKS cells, co-localizing with involucrin, a CCE component. A similar distribution in the region of the CCE was observed for E1^E4 protein in HPV 59-infected human epithelial tissues. Conclusions: The HPV 59 E1^E4 protein is cytoplasmic and co-localizes with an intact cytokeratin filament network in undifferentiated keratinocytes. The E1^E4 protein is distributed in the region of the CCE and co-localizes with involucrin in differentiated human keratinocytes, consistent with the intracellular distribution pattern observed in HPV 59-infected epithelium.
High Sustained Virologic Response Rate after Interferon Monotherapy in Japanese Hepatitis C Patients with a Low HCV RNA Titer and/or HCV Genotype 2
Authors: Yokosuka Osamu , Iwama Shosuke , Suzuki Noriaki , Takashi Motohide , Hirai Yasuo , Uchiumi Katsuo , Kimura Michio , Gotou Nobuaki , Hino Shinichi , Hayasaka Akira , Kanda Tatsuo , Kawai Shigenobu , Fukai Kenichi , Imazeki Fumio , Saisho Hiromitsu
Published: December 2004

Objective: Hepatitis C virus (HCV) RNA titer and HCV genotype are considered to be major determinants of the outcome of interferon monotherapy. To clarify whether interferon monotherapy is really effective in patients with the appropriate viral parameters, we prospectively examined these parameters and treated the patients with interferon monotherapy. Methods: Sixty-four patients with an HCV RNA titer <100 kIU/ml and/or HCV genotype 2 were enrolled in the study. Eighteen patients with an HCV RNA titer >100 kIU/ml and genotype 1 were also enrolled as controls. All patients were treated with 10 megaunits of interferon-α2b every day for 2 weeks and then 3 times a week for 24 weeks. Results: Of the 64 patients with either HCV RNA <100 kIU/ml and/or genotype 2, seven dropped out from the study. Of the remaining 57 who completed the treatment, 48 (84%) showed a virologic sustained response. In contrast, only 4 of the 18 patients (22%) with HCV RNA >100 kIU/ml and genotype 1 were virologic sustained responders (p < 0.001). Conclusion: Our current study showed that the patients with HCV RNA <100 kIU/ml and/or HCV genotype 2 are good candidates for interferon monotherapy.
Specific in vitro Interaction between Papillomavirus E2 Proteins and TBP-Associated Factors
Authors: Carrillo Elba , Garrido Efrain , Gariglio Patricio
Published: December 2004

The bovine and human papillomavirus (BPV/HPV) E2 proteins bind specifically to palindromic sequences ACCGN4CGGT that are concentrated within the viral long control region, where they regulate viral oncogene transcription. E2 can activate viral promoters over relatively large distances within the viral genome and was shown to cooperate with a number of cellular transcription factors. Transcriptional activator proteins, such as E2, are thought to act, at least in part, by influencing the assembly and/or stability of preinitiation complexes and it has been suggested that the transcription factor IID, composed by the TATA-binding protein (TBP) and numerous TBP-associated factors (TAFs), is a possible target of this important viral protein. In this paper, we demonstrate that E2 proteins associate in vitro with several TAFs, in particular with TAFII250 and TAFII80. In addition, we observed that the association of TAFII250 with BPV1 E2 is stronger than with HPV18 E2 and that the carboxy terminal domain of both viral proteins is involved in this interaction. On the other hand, TAFII80 binds with similar strength to both E2 proteins through their amino terminal region. These observations may help to explain the different behavior of bovine and human E2 proteins, since BPV E2 is a stronger transcriptional activator than HPV18 E2.
Angiotensin-Converting Enzyme Insertion-Deletion Polymorphism in Primary Open-Angle Glaucoma
Authors: Ozkur Mehtap , Erbagci İbrahim , Gungor Kivanc , Nacak Muradiye , Aynacioglu Sukru , Bekir Necdet A.
Published: December 2004

Purpose: To investigate the hypothesis that primary open-angle glaucoma (POAG) is associated with a common insertion-deletion (I/D) polymorphism in the angiotensin-converting enzyme (ACE) gene. Methods: ACE I/D polymorphism was investigated in a control group of healthy subjects (n = 101) and in a group of patients diagnosed with POAG (n = 104). Polymerase chain reaction detection of I/D polymorphism was used to determine the presence of the two ACE alleles in the groups. Results: Neither the I/D genotype distributions nor the allele frequencies differed significantly between POAG and control subjects (DD genotype 34.6 vs. 39.6%; ID genotype 53.9 vs. 40.6%; II genotype 11.5 vs. 19.8%, p = 0.1; D allele 61.5 vs. 60%; I allele 38.5 vs. 40%, p = 0.8). Conclusion: We could not identify a possible association of the I/D polymorphism in the ACE gene with POAG, however further studies with larger patient numbers in different populations are required to clarify the role of ACE gene in susceptibility to POAG.
Disfluency in Tourette Syndrome: Observational Study in Three Cases
Authors: van Borsel J. , Goethals L. , Vanryckeghem M.
Published: December 2004

It is often stated that stuttering is a common speech disorder in individuals with Tourette syndrome (TS). It has also been suggested, however, that the fluency failures observed in people with TS do not completely conform to the classic pattern of stuttering. The present paper describes the results of an analysis of the speech patterns of three individuals with TS. A picture emerged that bears some resemblance to stuttering, cluttering, and palilalia but that is also different from each of these disfluency types.
The Prevalence of Hepatitis C and Hepatitis G Virus Infection in Patients with B Cell Non-Hodgkin Lymphomas in Greece: A Hellenic Cooperative Oncology Group Study
Authors: Giannoulis E. , Economopoulos T. , Mandraveli K. , Giannoulis K. , Nikolaides C. , Zervou E. , Papageorgiou E. , Zoulas D. , Tourkantonis A. , Giannopoulos G. , Fountzilas G.
Published: December 2004

Our aim was to investigate the association between chronic hepatitis C virus (HCV) infection and B cell non-Hodgkin lymphoma (NHL) in the Greek population. We studied 120 patients (70 men and 50 women, mean age 59 years) diagnosed with NHL. One hundred and eight had B cell NHL (90%) and 12 had T cell NHL (10%). The presence of anti-HCV antibodies in patients and controls was investigated using the monoclonal enzymatic immunoassay (MEIA) method. The detection of HCV RNA and hepatitis G virus (HGV) RNA in patients with B cell NHL and anti-HCV-positive controls was performed using an RT-PCR technique. Anti-HCV antibodies were present in only 2 of the 108 patients with B cell NHL (1.9%), while the prevalence of HCV infection in the healthy population was 0.6%, and in patients with various solid tumors treated with chemotherapy, it was 0.99%. Ten of the 108 B cell NHL patients (9.26%) were diagnosed as HGV RNA positive, while the prevalence of HGV infection in 285 Greek blood donors was 0.7%. Our findings do not confirm a strong association between HCV infection and B cell NHL for Greek patients. The increased prevalence of HGV infection detected in patients with NHL could imply the potential participation of HGV in the pathogenesis of NHL.
Mediastinal Bulky Tumour in Hodgkin’s Disease and Prognostic Value of Positron Emission Tomography in the Evaluation of Post-Treatment Residual Masses
Authors: Keresztes Katalin , Lengyel Zsolt , Devenyi Katalin , Vadasz Györgyi , Miltenyi Zsofia , Illes Arpad
Published: December 2004

Among the 193 patients (82 female, 111 male) treated primarily for Hodgkin’s disease at our clinic between 1990 and 2001 and followed up until 2003, 42 (22%) had mediastinal bulky tumours (MBTs) by the Cotswolds criteria. The rate of MBT diagnosis was significantly greater in the early stage of the disease, these patients were younger and – in contrast to the other group – they all received combined therapy. No significant differences were found in the overall and relapse-free survival rate in the two groups, but relapse and death rates were lower in the patients with bulky tumours. Of the total number of patients, 27 underwent a total of 31 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) examinations, mainly for the evaluation of post-treatment residual mass viability. In the 12 positive cases, the majority of patients received further therapy. During the mean follow-up time of 58 months (range 5–98 months) after obtaining negative results, progression of the disease was found in 2 cases 14 and 23 months later, respectively. Based on our results, we conclude that FDG-PET examinations show a good correlation with clinical follow-up results.