bluuebunny/crossref_metadata_2025 huggingface dataset:
DILATON BRANE COSMOLOGY WITH SECOND ORDER STRING CORRECTIONS AND THE COSMOLOGICAL CONSTANT
Authors: KUIROUKIDIS APOSTOLOS
Published: February 2006

We consider, in five dimensions, the effective action from heterotic string which includes quantum gravity corrections up to (α′)2. The expansion, in the string frame, is in terms of |α′R|, where R is the scalar curvature and uses the third order Euler density, next to the Gauss–Bonnet term. For a positive tension brane and infinite extra dimension, the logarithmic class of solutions is less dependent from fine-tuning than in previous formulations. More importantly, the model suggests that in the full nonperturbative formulation, the string scale can be much lower than the effective Planck mass, without the string coupling to be vanishingly small. Also, a less severe fine-tuning of the brane tension is needed.
CHIRAL AND U(1)A RESTORATIONS HIGH IN THE HADRON SPECTRUM, SEMICLASSICAL APPROXIMATION AND LARGE Nc
Authors: GLOZMAN L. YA.
Published: February 2006

In quantum systems with large n (radial quantum number) or large angular momentum the semiclassical (WKB) approximation is valid. A physical content of the semiclassical approximation is that the quantum fluctuations effects are suppressed and vanish asymptotically. The chiral as well as U (1)A breakings in QCD result from quantum fluctuations. Hence these breakings must be suppressed high in the spectrum and the spectrum of high-lying hadrons must exhibit U (2)L × U (2)R symmetry of the classical QCD Lagrangian. This argument can be made stronger for mesons in the large Nc limit. In this limit all mesons are stable against strong decays and the spectrum is infinite. Hence, one can excite mesons of arbitrary large size with arbitrary large action, in which case the semiclassical limit is manifest. Actually we do not need the exact Nc = ∞ limit. For any large action there always exist such Nc that the isolated mesons with such an action do exist and can be described semiclassically. From the empirical fact that we observe multiplets of chiral and U (1)A groups high in the hadron spectrum it follows that Nc = 3 is large enough for this purpose.
FINE STRUCTURE OF BETA DECAY END POINT SPECTRUM
Authors: MASOOD SAMINA S. , NASRI SALAH , SCHECHTER JOSEPH
Published: February 2006

We note that the fine structure at the end point region of the beta decay spectrum is now essentially known using neutrino oscillation data, if the mass of one neutrino is specified. This may help to identify the effects of nonzero neutrino masses in future experiments. We also give a compact description of the entire range of allowed neutrino masses as a function of the third neutrino mass, m3. A three neutrino assumption is being made. An exact treatment of phase space kinematics is used, in contrast to the conventional approximate formula. This work is independent of theoretical models; however, additional restrictions due to the assumption of a "complementary ansatz" for the neutrino mass matrix are also discussed. The ansatz implies that the values of the three neutrino masses should approximately be able to form a triangle. It is noted that most of the presently allowed neutrino mass sets have this triangular property.
PROBING POLARIZED GLUON DISTRIBUTIONS THROUGH CHARMED HADRON PRODUCTION IN POLARIZED pp COLLISIONS AT BNL-RHIC ENERGY
Authors: MORII TOSHIYUKI , OHKUMA KAZUMASA
Published: February 2006

In order to extract information about behavior of polarized gluons in the nucleon, charmed hadron productions, i.e. D*+ meson and [Formula: see text] baryon productions, are studied in polarized pp reactions at BNL-RHIC energy. For these processes, the spin correlation asymmetry DLL between the target proton and the produced charmed hadron, and its statistical sensitivity δDLL are calculated. From analyses on these processes, we found that the pseudorapidity distribution of DLL in the limited transverse momentum region is quite effective for distinguishing the model of polarized gluons as well as the model of spin-dependent fragmentation functions.
NEW HIGH INPUT IMPEDANCE VOLTAGE-MODE LOWPASS, BANDPASS AND HIGHPASS FILTER USING CURRENT FEEDBACK AMPLIFIERS
Authors: SHAH NISAR AHMAD , MALIK MOHD AMIN
Published: February 2006

A new high input impedance filter employing three current feedback amplifiers (CFAs) and six passive elements, three of them are grounded, is presented. The proposed circuit offers the following advantages: simultaneous realization of lowpass (LP), bandpass (BP) and highpass (HP) filtering functions, employs two grounded capacitors, exhibits high input and low output impedances which permits easy cascade connection, low passive sensitivity figures and orthogonal control of resonance frequency (ωo) and bandwidth (ωo/Q). PSPICE simulation results are given to verify the theoretical calculations.
A REINFORCEMENT LEARNING SCHEME FOR DYNAMIC ENERGY MANAGEMENT IN EMBEDDED SYSTEMS
Authors: VISWANATHAN LAKSHMI PRABHA , MONIE ELWIN CHANDRA
Published: February 2006

Dynamic power management is a technique to reduce power consumption of electronic systems by selectively shutting down idle components. In this paper, an intelligent approach is presented based on reinforcement learning to predict the best policy amongst the existing DPM policies. Reinforcement learning is a computational approach to understanding and automating goal-directed learning and decision-making. The effectiveness of this approach is demonstrated by an event-driven simulator, which is designed using JAVA for power-manageable embedded devices. The results of the experiments conducted in this regard establish that the proposed DPM scheme enhances power savings by 10 to 28%.
DSP-CONTROLLED MULTIPHASE HYSTERETIC VRM WITH CURRENT SHARING EQUALIZATION
Authors: ABU-QAHOUQ JABER , PONGRATANANUKUL NATORN , KASPARIS TAKIS , BATARSEH ISSA
Published: February 2006

Many of the new high-speed high-integration density Integrated Circuits (ICs) and future generation of microprocessor powering requirements can be successfully achieved with voltage-mode hysteretic control applied to interleaved multiphase Point-of-Load (POL) DC–DC converters or Voltage Regulator Modules (VRMs). This is because of the several advantages that can be achieved by combining the advantages of hysteretic control and interleaving. However, there are several challenges in combining the two techniques, the most prominent being the current sharing and equalization between the interleaved phases. In this communication, we present a solution based on a real-time DSP controller. Challenges of the implementation will be discussed and experimental results obtained from a prototype will be presented.
CMOS DESIGN OF ANALOG FUZZY SYSTEM
Authors: WANG WEIZHI , JIN DONGMING
Published: February 2006

This paper proposes several improved CMOS analog integrated circuits for fuzzy inference system as the general modules, including voltage-mode implementations of minimization circuit, programmable Gaussian-like membership function circuit, and centroid algorithm normalization circuit without using division. A two-input/one-output fuzzy system composed of these circuits is implemented and testified as a nonlinear function approximator. HSPICE simulation results show that the proposed circuits provide characteristics of high operation capacity, simple inference, low power dissipation, and high precision.
IMPROVED ALGORITHMS FOR LOW POWER MULTIPLEXOR DECOMPOSITION
Authors: YANG SHAOFA , LEONG HON WAI
Published: February 2006

It has been estimated that multiplexors (MUXes) make up a major portion of the circuitry in a typical chip. Therefore, to reduce power consumption of a chip, it is important to consider the design of MUXes that consumes less power. This is called the low power MUX decomposition problem and has been studied in Ref. 1. This paper improves on the results of Ref. 1 in two ways: (a) we propose a method to speed up the algorithms in Ref. 1, and (b) we propose a post-optimization procedure to further reduce the overall power dissipation of decompositions obtained by any MUX decomposition algorithm. Using this post-optimization procedure, we have been able to further reduce the power dissipation results of Ref. 1.
LOSS AWARE RATE ALLOCATIONS IN H.263 CODED VIDEO TRANSMISSIONS
Authors: SU XIAO , WAH BENJAMIN W.
Published: February 2006

For packet video, information loss and bandwidth limitation are two factors that affect video playback quality. Traditional rate allocation approaches have focused on optimizing video quality under bandwidth constraint alone. However, in the best-effort Internet, packets carrying video data are susceptible to losses, which need to be reconstructed at the receiver side. In this paper, we propose loss aware rate allocations in both group-of-block (GOB) level and macroblock level, given that certain packets are lost during transmissions and reconstructed using simple interpolation methods at the receiver side. Experimental results show that our proposed algorithms can produce videos of higher quality when sent over lossy Internet.
ENDEMIC FLUOROSIS THROUGH DRINKING WATER AND ITS REMEDIAL MEASURE BY BACTERIAL POPULATION — A MATHEMATICAL MODEL
Authors: BAGH BIDISHA , DAS KALYAN , RAY SANTANU
Published: February 2006

Fluoride-contaminated drinking water is a serious public health hazard in some parts of India. Field surveys have been conducted in fluoride-affected areas of the Birbhum district, West Bengal, India. From these surveys, it is found that in certain locations the drinking water contains less fluoride (within the permissible limit1) than in adjoining areas. We have isolated a strain of Streptococcus species from these wells that has the ability to remove the fluoride ion from the water. We have grown the bacteria in different concentrations of fluoride and monitored the decline in the free fluoride ion concentration. A simplified model of fluoride and bacterial dynamics is proposed. The model is handled both analytically and numerically. For numerical solution mainly our own laboratory data are used. Calibration and validation are performed with different sets of experimental data. Analytical solutions show that the bacterial consumption and growth rates are the most important parameters in the system. Analysis shows asymptotic stability of the system.
COHERENCE RESONANCE PHENOMENA IN AN EXCITABLE SYSTEM DRIVEN BY COLORED NOISE
Authors: BEATO V. , ENGEL H.
Published: February 2006

We study the coherence of noise-induced excitations in a modified stochastic Oregonator model for the light-sensitive Belousov-Zhabotinsky (BZ) reaction assuming that the intensity of the applied illumination is a spatio-temporal stochastic field with finite correlation time and correlation length. For a single excitable element, we find coherence resonance (CR) with respect to the correlation time. In the spatially extended medium of diffusively coupled excitable elements, we observe CR for suitable combinations of the correlation time and length of the noise.
Thyroid hormones increase inducible nitric oxide synthase gene expression downstream from PKC-ζ in murine tumor T lymphocytes
Authors: Barreiro Arcos María Laura , Gorelik Gabriela , Klecha Alicia , Genaro Ana María , Cremaschi Graciela A.
Published: February 2006

Regulation of cell proliferation by thyroid hormone (TH) has been demonstrated, but the effect of THs and the mechanisms involved in lymphocyte activity have not been elucidated. Differential expression of PKC isoenzymes and high nitric oxide synthase (NOS) activity have been described in tumor T lymphocytes. We have analyzed the direct actions of TH on normal T lymphocytes and BW5147 T lymphoma cells in relation to PKC and NOS activities. THs increased tumor and mitogen-induced normal T lymphocyte proliferation. PKC isoenzyme-selective blockers impaired these effects in both cell types, indicating the participation of Ca2+-dependent and -independent isoenzymes in normal and tumor cells, respectively. TH actions were blunted by extra- and intracellular Ca2+ blockers only in normal T lymphocytes, whereas NOS blockers impaired TH-induced proliferation in T lymphoma cells. Incubation for 24 h with TH induced a rise in total and membrane-associated PKC activities in both cell types and led to a rapid and transient effect only in tumor cells. THs increased atypical PKC-ζ expression in BW5147 cells and classical PKC isoenzymes in mitogen-stimulated normal T cells. TH augmented NOS activity and inducible NOS protein and gene expression only in tumor cells. Blockade of PKC and the atypical PKC-ζ isoform inhibited TH-mediated stimulation of inducible NOS and cell proliferation. These results show, for the first time, that differential intracellular signals are involved in TH modulation of lymphocyte physiology and pathophysiology.
Role of boundary conditions in an experimental model of epithelial wound healing
Authors: Nikolić Djordje L. , Boettiger Alistair N. , Bar-Sagi Dafna , Carbeck Jeffrey D. , Shvartsman Stanislav Y.
Published: February 2006

Coordinated cell movements in epithelial layers are essential for proper tissue morphogenesis and homeostasis, but our understanding of the mechanisms that coordinate the behavior of multiple cells in these processes is far from complete. Recent experiments with Madin-Darby canine kidney epithelial monolayers revealed a wave-like pattern of injury-induced MAPK activation and showed that it is essential for collective cell migration after wounding. To investigate the effects of the different aspects of wounding on cell sheet migration, we engineered a system that allowed us to dissect the classic wound healing assay. We studied Madin-Darby canine kidney sheet migration under three different conditions: 1) the classic wound healing assay, 2) empty space induction, where a confluent monolayer is grown adjacent to a slab of polydimethylsiloxane and the monolayer is not injured but allowed to migrate upon removal of the slab, and 3) injury via polydimethylsiloxane membrane peel-off, where an injured monolayer migrates onto plain tissue culture surface, as in the case of empty space induction allowing for direct comparison. By tracking the motion of individual cells within the sheet under these three conditions, we show how the dynamics of the individual cells’ motion is responsible for the coordinated migration of the sheet and is coordinated with the activation of ERK1/2 MAPK. In addition, we demonstrate that the propagation of the waves of MAPK activation depends on the generation of reactive oxygen species at the wound edge.
Increased NHE1 expression is associated with serum deprivation-induced differentiation in immortalized rat proximal tubule cells
Authors: Carraro-Lacroix Luciene Regina , Ramirez Marco Antonio , Zorn Telma M. T. , Rebouças Nancy Amaral , Malnic Gerhard
Published: February 2006

We studied the proton secretion mechanisms involved with pHiregulation in immortalized rat proximal tubule cells (IRPTC), a SV40-immortalized cell line derived from rat proximal tubule, and characterized the effects of serum deprivation on them. Using pHimeasurements with the fluorescent probe BCECF, we demonstrated that the IRPTC express both Na+/H+exchanger and H+-ATPase, but only NHE1 is modulated by serum deprivation. In these cells, 24 h of serum starvation increased pHifrom 7.08 ± 0.008 ( n = 34) to 7.18 ± 0.018 ( n = 33) as well as the pH recovery rate from intracellular acidification with NH4Cl from 0.29 ± 0.022 pH U/min ( n = 14) to 0.50 ± 0.024 pH U/min ( n = 14), without modifying their buffering capacity. These effects were followed by several modifications in morphological features, indicating an increase in differentiation status. The altered activity of NHE1 was consistent with an increase of both transcription and translation of the antiporter, as the utilization of actinomycin D and cycloheximide significantly inhibited the upregulation of NHE1 induced by serum withdrawal. Inhibition of tyrosine phosphorylation by genistein blocked the serum deprivation-dependent activation of NHE. Moreover, the pharmacological inhibition of MEK1/2, the upstream activator of ERK1/2 by UO-126, significantly inhibited the stimulatory effect of serum starvation on Na+/H+exchanger activity, whereas the putative p38 MAPK inhibitor SB-203580 failed to cause any effect on pHirecovery rates. Our findings indicate that during IRPTC differentiation by serum deprivation, there was a net enhancement of NHE1 activity. This upregulation of NHE by serum removal was consistent with an increase of RNA and protein synthesis of the exchanger, which depends on tyrosine kinase phosphorylation and ERK pathway activation.
Metabolic acidosis has dual effects on sodium handling by rat kidney
Authors: Faroqui Somia , Sheriff Sulaiman , Amlal Hassane
Published: February 2006

Chronic metabolic acidosis (CMA) is associated with decreased NaCl reabsorption in the proximal tubule (PT). However, the effect of CMA on Na+transport in the distal tubule (DT) and collecting duct (CD) is poorly understood. Rats were placed in metabolic cages and had access to water (control), 0.28 M NH4Cl, or 0.28 M KCl solutions in a pair-feeding protocol for 5 days (5d). Metabolic acidosis developed within 24 h in NH4Cl-, but not in KCl-loaded rats. Interestingly, NH4Cl- but not KCl-loaded rats exhibited a significant natriuresis after 24 h of treatment. Urinary Na+excretion increased from 1.94 to 2.97 meq/24 h ( P < 0.001) and returned to below baseline level (1.67 meq/l) after 5d of CMA. The protein abundance of the cortical Na-Cl cotransporter (NCC) remained unchanged at 24 h, but increased significantly ( P < 0.01) after 5d of CMA. The protein abundance of α-, β-, and γ-subunits of the epithelial Na+channel (ENaC) in the cortex decreased sharply during the first 24 h and then returned to baseline levels after 5d of CMA. Interestingly, Sgk1 expression decreased after 24 h (−31%, P < 0.05) and then returned to baseline after 5d of CMA. Nedd4–2 expression was not altered during CMA. CMA enhanced serum aldosterone levels by 54% and increased the expression of aldosterone synthase in the adrenal gland by 134% after 5d of CMA. In conclusion, metabolic acidosis has dual effects on urinary Na+excretion. The early natriuresis results from decreased Na+reabsorption in the PT and Sgk1-related decreased ENaC activity in the DT and CD. Aldosterone-induced upregulation of NCC, Sgk1, and ENaC likely contributes to the antinatriuretic phase of metabolic acidosis. This adaptation prevents Na+wasting and volume depletion during chronic acid insult.
Preplaced cell division: a critical mechanism of autoprotection againstS-1,2-dichlorovinyl-l-cysteine-induced acute renal failure and death in mice
Authors: Korrapati Midhun C. , Chilakapati Jaya , Lock Edward A. , Latendresse John R. , Warbritton Alan , Mehendale Harihara M.
Published: February 2006

Previous studies have shown that renal injury initiated by a lethal dose of S-1,2-dichlorovinyl-l-cysteine (DCVC) progresses due to inhibition of cell division and hence renal repair, leading to acute renal failure (ARF) and death in mice. Renal injury initiated by low to moderate doses of DCVC is repaired by timely and adequate stimulation of renal cell division, tubular repair, restoration of renal structure and function leading to survival of mice. Recent studies have established that mice primed with a low dose of DCVC (15 mg/kg ip) 72 h before administration of a normally lethal dose (75 mg/kg ip) are protected from ARF and death (nephro-autoprotection). We showed that renal cell division and tissue repair stimulated by the low dose are sustained even after the lethal dose administration resulting in survival from ARF and death. If renal cell division induced by the low dose is indeed the critical mechanism of this autoprotection, then its ablation by the antimitotic agent colchicine (1.5 mg CLC/kg ip) should abolish autoprotection. The present interventional experiments were designed to test the hypothesis that DCVC autoprotection is due to stimulated cell division and tissue repair by the priming low dose. CLC intervention at 42 and 66 h after the priming dose resulted in marked progressive elevation of plasma blood urea nitrogen and creatinine resulting in ARF and death of mice. Light microscopic examination of hematoxylin and eosin-stained kidney sections revealed progression of renal necrosis concordant with progressively failing renal function. With CLC intervention, S-phase stimulation (as assessed by BrdU pulse labeling), G1-to-S phase clearance, and cell division were diminished essentially abolishing the promitogenic effect of the priming low dose of DCVC. Phospho-retinoblastoma protein (P-pRB), a crucial protein for S-phase stimulation, and other cellular signaling mechanisms regulating P-pRB were investigated. We report that decreased P-pRB via activation of protein phosphatase-1 by CLC is the critical mechanism of this inhibited S-phase stimulation and ablation of autoprotection with CLC intervention. These findings lend additional support to the notion that stimulated cell division and renal tissue repair by the priming dose of DCVC are the critical mechanisms that allow sustained compensatory tissue repair and survival of mice in nephro-autoprotection.
Live high-train low for 24 days increases hemoglobin mass and red cell volume in elite endurance athletes
Authors: Wehrlin Jon Peter , Zuest Peter , Hallén Jostein , Marti Bernard
Published: February 2006

The effect of live high-train low on hemoglobin mass (Hbmass) and red cell volume (RCV) in elite endurance athletes is still controversial. We expected that Hbmass and RCV would increase, when using a presumably adequate hypoxic dose. An altitude group (AG) of 10 Swiss national team orienteers (5 men and 5 women) lived at 2,500 m (18 h per day) and trained at 1,800 and 1,000 m above sea level for 24 days. Before and after altitude, Hbmass, RCV (carbon monoxide rebreathing method), blood, iron, and performance parameters were determined. Seven Swiss national team cross-country skiers (3 men and 4 women) served as “sea level” (500–1,600 m) control group (CG) for the changes in Hbmass and RCV. The AG increased Hbmass (805 ± 209 vs. 848 ± 225 g; P < 0.01) and RCV (2,353 ± 611 vs. 2,470 ± 653 ml; P < 0.01), whereas there was no change for the CG (Hbmass: 849 ± 197 vs. 858 ± 205 g; RCV: 2,373 ± 536 vs. 2,387 ± 551 ml). Serum erythropoietin ( P < 0.001), reticulocytes ( P < 0.001), transferrin ( P < 0.001), soluble transferrin receptor ( P < 0.05), and hematocrit ( P < 0.01) increased, whereas ferritin ( P < 0.05) decreased in the AG. These changes were associated with an increased maximal oxygen uptake (3,515 ± 837 vs. 3,660 ± 770 ml/min; P < 0.05) and improved 5,000-m running times (1,098 ± 104 vs. 1,080 ± 98 s; P < 0.01) from pre- to postaltitude. Living at 2,500 m and training at lower altitudes for 24 days increases Hbmass and RCV. These changes may contribute to enhance performance of elite endurance athletes.
In Vitro Odor-Aversion Conditioning in a Terrestrial Mollusk
Authors: Inoue Tsuyoshi , Murakami Masayoshi , Watanabe Satoshi , Inokuma Yasuko , Kirino Yutaka
Published: February 2006

We developed an in vitro odor-aversion conditioning system in the terrestrial mollusk, Limax, and found a behavioral correlate of network oscillation in the olfactory CNS. We first examined the odor-induced behavior of Limax, after odor-aversion conditioning in vivo. Shortening of mantle muscles was specifically observed in response to aversively conditioned odors. We previously identified that parietal nerves, which project to the mantle muscle in Limax, regulate shortening of the mantle muscle. We therefore isolated whole brains containing noses (sensory organs) and parietal nerves (motor output), and applied an odor-aversion conditioning paradigm to these in vitro preparations. Before the in vitro conditioning, application of attractive odors to the noses did not elicit any discharge in the parietal nerves. However, after odor-aversion conditioning, discharges in the parietal nerves were observed in response to the natively attractive but aversively conditioned odors. We also found that network oscillation frequency in the procerebrum (PC), the olfactory CNS of Limax, increased specifically in response to the aversively conditioned odors that elicited avoidance behavior. In naive (nonconditioned) preparations, increases in the PC oscillation frequency were observed specifically in response to innately aversive odors. These results indicate that the isolated brains have an ability of odor learning. They also suggest that changes in PC network oscillation are associated with aversively conditioned and innately aversive odors, both of which elicit avoidance behavior. This in vitro conditioning system would be an effective approach for exploring the neural mechanism to determine the aversion to odors.
Respiration-Related Rhythmic Activity in the Rostral Medulla of Newborn Rats
Authors: Onimaru Hiroshi , Kumagawa Yuko , Homma Ikuo
Published: February 2006

There are at least two respiration-related rhythm generators in the medulla: the pre-Bötzinger complex, which produces inspiratory (Insp) neuron bursts, and the parafacial respiratory group (pFRG), which produces predominantly preinspiratory (Pre-I) neuron bursts. The pFRG Pre-I neuron activity has not been correlated with motor neuron activity in slice or block preparations of rostral medulla. In this study, we attempted to detect pFRG Pre-I activity as motor output in the rostral medulla. We recorded respiratory activity of the facial nerve in the brain stem–spinal cord preparation of 0- to 2-day-old rats. Facial nerve activity consisted of preinspiratory, Insp, and postinspiratory activity. Pre- and postinspiratory activity corresponded well with membrane potential trajectories of Pre-I neurons in the rostral ventrolateral medulla. In response to perfusion of 1 μM DAMGO (a μ-opiate agonist), fourth cervical ventral root (C4) Insp activity was depressed and facial nerve activity continued to synchronize with Pre-I neuron bursts. After transverse sectioning between the levels of the pre-Bötzinger complex and the pFRG, C4 Insp activity recovered within 15 min, but facial nerve activity was inhibited. When DAMGO was applied, C4 Insp activity was inhibited, and rhythmic facial nerve activity recovered. Subsequent elevation of K+ concentration reinduced C4 activity, but facial nerve activity was inhibited. Whole cell recordings in the rostral block revealed the presence of putative Pre-I neurons, the activity of which was synchronized with facial nerve activity. These results show that the rostral medulla, not including the pre-Bötzinger complex, produces Pre-I–like rhythmic activity that can be monitored as facial nerve motor output in newborn rat in vitro preparations.
Axo-Somatic and Apical Dendritic Kv7/M Channels Differentially Regulate the Intrinsic Excitability of Adult Rat CA1 Pyramidal Cells
Authors: Yue Cuiyong , Yaari Yoel
Published: February 2006

Kv7/KCNQ/M channel subunits are widely expressed in peripheral and central neurons, where they give rise to a muscarinic-sensitive, subthreshold, and noninactivating K+current (M current). Immunohistochemical data suggest that Kv7/M channels are expressed in both axons, somata and dendrites, but their distinctive roles in these compartments are not known. Here we used intracellular microelectrode recordings to monitor the effects of selective Kv7/M channel modulators focally applied to the axo-somatic region and to the apical dendrites of adult rat CA1 pyramidal cells. We show that both compartments express functional Kv7/M channels that synergistically control intrinsic neuronal excitability, albeit in different ways. Axo-somatic Kv7/M channels activate during the spike afterdepolarization (ADP) and counteract the depolarizing drive furnished by conjointly activated persistent Na+channels. Thereby they limit the size and duration of the spike ADP and prevent its escalation into a somatic spike burst. Apical dendritic Kv7/M channels do not ordinarily regulate the somatic spike ADP and spike output. In hyperexcitable conditions that promote Ca2+electrogenesis in these dendrites, they elevate the threshold for initiating Ca2+spikes and associated downstream spike bursts. Thus the concerted activity of Kv7/M channels in both compartments serves to reduce the propensity to generate self-sustained burst responses and fosters a regular, stimulus-graded spike output of the neuron. Given that the activity of Kv7/M channels is regulated by multiple neurotransmitters, they may provide a substrate for neuromodulation of neuronal input/output relations at both the axo-somatic and apical dendritic regions.
Alcohol-Related Diseases of the Mouth and Throat
Authors: Riedel Frank , Goessler Ulrich R. , Hörmann Karl
Published: February 2006

Chronic consumption of alcoholic beverages is an accepted social custom worldwide. In the upper aerodigestive tract, local morphologic, metabolic and functional alterations are present due to alcohol consumption. A clinical link between the chronic consumption of alcohol and head and neck cancer has been observed for decades. While alcohol was described initially as a risk enhancer only in smokers, a number of epidemiological studies have now provided sufficient evidence that chronic alcohol consumption increases the risk of head and neck cancer independent of exposure to tobacco smoke. The systemic effects of alcohol interact with local changes in the morphology and function of the salivary glands. In addition, alcohol leads to accumulation of pathologic microbes within the mucosa, leading to chronic infection. Susceptibility to carcinogens and cell proliferation in the mucosa are increased, resulting in genetic changes with the development of dysplasia, leukoplacia and carcinoma. Chronic alcohol consumption is correlated with an increased risk of cancer and an increased mortality in a dose-effect relationship. A number of biologically plausible mechanisms exist by which alcohol may cause cancer. These mechanisms are discussed in this article.
Alcohol-Related Diseases of the Esophagus and Stomach
Authors: Franke Andreas , Teyssen Stephan , Singer Manfred V.
Published: February 2006

The present review summarizes the clinically relevant effects of acute and chronic alcohol consumption on motility, mucosal inflammation and cancer of the esophagus and the stomach. Alcohol consumption results in a significant increase in the morbidity of these two organs, the most important probably being the significant increase in the development of esophageal cancer. This review refers to epidemiologic and systematic experimental data to elucidate the clinical impact of alcohol consumption as well as the underlying alcohol-induced pathophysiologic mechanisms for these esophageal and gastric diseases. Much research is still needed to clarify the effects of alcohol itself and the byproducts that result during the production of the different types of alcoholic beverages on dismotility and mucosal injury to the esophagus and stomach.
Effect of Alcohol Consumption on the Gut
Authors: Rajendram Rajkumar , Preedy Victor R.
Published: February 2006

Both acute and chronic alcohol consumption have severe effects on the structure and function of the entire gastrointestinal tract (GIT) which result in a vicious cycle. The healthy person who begins to drink heavily, first experiences the toxic effects of high concentrations of ethanol. Mucosal damage compromises the basic functions of the GIT. Suppression of the gastrointestinal immune system and increased transport of toxins across the mucosa result in increased susceptibility to infections. Inhibition of digestion, absorption and secretion cause diarrhea and reduce the transfer of nutrients to the rest of the body. As the individual becomes more dependent on alcohol, the functional reserve and regenerative capacity of the GIT are overwhelmed and malnutrition increases. The rate of progression of this cycle depends on several factors including nutritional intake. Whilst the clinical effects of alcohol are well recognized, more research is required to fully elucidate the underlying mechanisms.
Alcoholic Pancreatitis
Authors: Schneider Alexander , Singer Manfred V.
Published: February 2006

A history of excessive alcohol consumption is found in the majority of patients with chronic pancreatitis, and numerous research efforts revealed insights into the pathogenesis of alcohol-induced pancreatic damage. However, the exact mechanisms underlying the disease are not yet clarified, and the origin of alcoholic chronic pancreatitis continues to be the topic of speculation and investigation. This article provides an overview about the epidemiology of alcoholic chronic pancreatitis, the epidemiologic association of alcohol intake and pancreatitis and the clinical course of the disease. Finally, this article summarizes several hypothetical concepts that try to explain the early and late pathophysiological mechanisms of acute and chronic pancreatitis.
Clinical Syndromes of Alcoholic Liver Disease
Authors: Adachi Masayuki , Brenner David A.
Published: February 2006

Background and Aims: Alcoholic liver disease continues to be a major health problem with respect to both morbidity and mortality. To understand the clinical syndromes of alcoholic liver disease, this review highlights the papers on both clinical and basic research of alcoholic liver disease, especially on steatosis, alcoholic hepatitis and fibrosis. Methods: The various forms of alcoholic liver disease are described, and knowledge about the clinical and pathophysiological features of different stages of alcoholic liver disease are summarized. Results: Clinical studies combined with basic research have established a spectrum of alcoholic liver disease from steatosis to steatohepatitis, fibrosis, and cirrhosis. New insights into the pathogenesis of alcoholic liver disease include the key roles of the excess production of cytokines, reactive oxygen species, and the shortage of protective mediators, including adiponectin. Conclusion: These new insights will lead to new specific therapies for the treatment of alcoholic hepatitis and alcoholic liver fibrosis.
Alcohol Consumption and Cancer of the Gastrointestinal Tract
Authors: Seitz Helmut K. , Maurer Britta , Stickel Felix
Published: February 2006

Epidemiological data have identified chronic alcohol consumption as a significant risk factor for upper gastrointestinal cancer (oropharynx, hypopharynx, esophagus) and colorectal cancer. Pathophysiological mechanisms include generation of acetaldehyde (AA) and reactive oxygen species (ROS), induction of cytochrome P 4502E1 (CYP2E1), and local and nutritional factors. Genetic polymorphisms of alcohol-metabolizing enzymes may individually influence the risk of carcinogenesis. AA, the first and major metabolite of ethanol, has proven to be the most carcinogenic and mutagenic agent in alcohol-associated cancer. Gastrointestinal bacteria as well as various isozymes of alcohol dehydrogenase (ADH) are capable of metabolizing ethanol to AA thus leading to an increased cell turnover of the gastrointestinal mucosa after chronic alcohol consumption. In Caucasians, ADH1C polymorphism is most important, for the ADH1C*1 transcription results in an ADH isoenzyme 2.5 times more active than that from ADH1C*2, which is associated with an increase in AA production. Additionally, oxidative stress due to an induction of CYP2E1 in the gastrointestinal mucosa of alcoholics should be considered as another key factor in alcohol-induced carcinogenesis. Nutritional deficiencies, i.e. lack of folic and retinoic acid, as well as malnutrition itself may also contribute to the development of gastrointestinal cancer.
Therapy and Supportive Care of Alcoholics: Guidelines for Practitioners
Authors: Kienast Thorsten , Heinz Andreas
Published: February 2006

Background/Aims: Alcoholism is a widespread disorder in our societies. However, only a small percentage of alcoholics appear in specific psychotherapeutic treatment programs. The vast majority are seen by general practitioners or experts of other medical specialties where they are treated intensively for their alcohol-induced comorbidities. But the reason for these comorbidities, alcoholism itself, is rarely treated. This article provides a guideline for specialists and non-specialists on how to treat these patients correctly in nonspecific treatment programs and how to increase motivation to stay abstinent. Moreover, the concept can be quickly and easily integrated into the daily routine of any therapeutic team. Methods: Literature on the therapeutic methods of brief interventions, motivational interviewing as well as pharmacological relapse prevention was reviewed in PubMed for the years 1991–2005. Results/Conclusion: The burden of disease of alcoholism and alcohol abuse as primary disorders is highly evident but often underestimated even by therapists of various medical disciplines. Systematic studies of the brief intervention method, motivational interviewing and also pharmacological treatment with acamprosate have shown that these are potent methods that are easily used to increase the duration of abstinence and patients’ motivation to take part in further specific treatment.
A Case of Pregnancy Associated Hypereosinophilia with Hyperpermeability Symptoms
Authors: Ogasa Maki , Nakamura Yasuhiko , Sanai Hiromi , Ueda Kazuyuki
Published: February 2006

Background: Hypereosinophilia commonly reflects an allergic, infectious, or neoplastic disease, and is a rare complication during pregnancy. Case: A 27-year-old pregnant woman was referred to our hospital due to dyspnea at 10 weeks’ gestation. Ultrasound examination showed the presence of pericardial effusion, pleural effusion, and ascites. Fluid transfusion, diuretic administration, and oxygen supplementation gradually improved the symptoms. Thereafter, the blood eosinophil count increased acutely and the fetus died. Following cessation of pregnancy the blood eosinophil count gradually decreased. Laboratory examinations did not assist the diagnosis of eosinophilia. Conclusion: This is the first case of hypereosinophilia associated with the life-threatening hyperpermeability symptoms, i.e., pericardial effusion, pleural effusion, and ascites, during early pregnancy.
Antitumoural Effects of the Pyridyl Cyanoguanidine CHS 828 on Three Different Types of Neuroendocrine Tumours Xenografted to Nude Mice
Authors: Johanson Viktor , Arvidsson Yvonne , Kölby Lars , Bernhardt Peter , Swärd Christina , Nilsson Ola , Ahlman Håkan
Published: February 2006

CHS 828, a cyanoguanidine with potent experimental antitumoural activity, inhibits activation of nuclear factor-ĸB. In the present study, marked antitumoural activity of peroral CHS 828 was shown against three different human neuroendocrine tumours, midgut carcinoid (GOT1), pancreatic carcinoid (BON), and medullary thyroid carcinoma (GOT2), transplanted in nude mice. Our results indicate that CHS 828 can be a candidate drug for treatment of neuroendocrine tumours.
Acute-on-Chronic Renal Failure in the Rat: Functional Compensation and Hypoxia Tolerance
Authors: Goldfarb Marina , Rosenberger Christian , Abassi Zaid , Shina Ahuva , Zilbersat Fani , Eckardt Kai U. , Rosen Seymour , Heyman Samuel N.
Published: February 2006

Background: We hypothesized that chronic renal parenchymal disease may predispose to acute renal failure (ARF), facilitating the induction of hypoxic medullary tubular injury. Methods: To induce chronic renal parenchymal injury, rats underwent sham operation (control) or bilateral 50-min clamping of the renal artery [ischemia-reperfusion (IR)]. One or 3 months later, both groups were subjected to an ARF protocol, consisting of radiocontrast and the inhibition of prostaglandin and nitric oxide synthesis. Renal function and morphology were determined 24 h later. Results: Chronic tubulointerstitial changes (fibrosis, atrophy and hypertrophy) in the IR group correlated with baseline tubular function, but glomerular function was preserved. Functional deterioration after the ARF protocol was only marginally more pronounced in the IR group, and the degree of medullary acute tubular necrosis (ATN) was unaffected by prior IR. The extent of both tubular necrosis and chronic tubulointerstitial changes independently predicted the acute decline in renal function. Immunostaining of IR kidneys disclosed critically low medullary pO2 (determined by pimonidazole adducts), regional hypoxic cell response (hypoxia-inducible factors) and upregulation of endothelin-B receptors. Conclusions: Compensatory changes result in normal plasma creatinine 1 and 3 months after IR, despite diminished tubular function. Preexisting renal disease only marginally predisposes to ARF, and the extent of ATN is not significantly enhanced. These findings illustrate the complex interaction between chronic and acute renal injury and dysfunction and parallel the difficulty of their assessment in the clinical practice. Adaptive cellular responses to chronic hypoxia in conjunction with parenchymal loss and decreased oxygen demand might alleviate acute hypoxic injury.
Enhanced Effect of Combined Treatment with SMP-534 (Antifibrotic Agent) and Losartan in Diabetic Nephropathy
Authors: Sugaru Eiji , Nakagawa Tsutomu , Ono-Kishino Michiko , Nagamine Jun , Tokunaga Teruhisa , Kitoh Makoto , Hume W. Ewan , Nagata Ryu , Taiji Mutsuo
Published: February 2006

Background/Aims: Diabetic nephropathy is now the most common cause of end-stage renal disease. It is also clear that the current therapy, angiotensin II blockage, cannot prevent the progression of diabetic nephropathy. We had previously demonstrated that an antifibrotic agent, SMP-534, reduced extracellular matrix production induced by transforming growth factor-β in vitro, and that SMP-534 prevented renal fibrosis and urinary albumin in diabetic db/db mice via a nonantihypertensive mechanism. We expected that combined use of SMP-534 and losartan would produce a more highly renoprotective action. Methods: We examined the effects of combined treatment with SMP-534 and losartan on urinary albumin and glomerular fibrosis in db/db mice. Diet containing these agents was provided from age 9 to 25 weeks. Blood and urine analyses were performed at 8, 17, and 25 weeks. At the end of the study, kidney tissues were histologically analyzed. Results: SMP-534 significantly suppressed an increase in urinary albumin excretion and ameliorated the progression of glomerular fibrosis in db/db mice, whereas losartan did not. Combined treatment with SMP-534 and losartan markedly prevented the increase of urinary albumin excretion compared with treatment with either SMP-534 or losartan alone. In contrast, renal histological analysis revealed that combined treatment did not significantly prevent an increase of mesangial expansion in the kidney compared with treatment with SMP-534 alone. Conclusion: A combination of the two agents, SMP-534 and losartan, might be a valuable therapeutic approach for the treatment of diabetic nephropathy.
Democracy, Community, Trust
Authors: Manion Melanie
Published: February 2006

This article systematically investigates the impact of elections in rural China on a basic element of the elite-mass relationship: beliefs of ordinary citizens that their leaders are trustworthy. It analyzes data from two surveys of randomly sampled villagers in the same 57 villages in 1990 and 1996, merged with a set of separately collected data detailing features of elections in these villages during the same period of time. The analyses take advantage of uneven progress in grassroots democratization and ask how variation in democratic electoral quality across villages is associated with variation in changed views about the probity (or venality) of local leaders. Results strongly suggest that formal institutions of electoral democracy matter: Designs that feature contestation and encourage voter participation do better at promoting beliefs that leaders are trustworthy. At the same time, results point to the importance of informal community institutions of lineage relationships.
Legal Opportunity Structures and Social Movements
Authors: Wilson Bruce M. , Rodríguez Cordero Juan Carlos
Published: February 2006

How does institutional change in established democracies affect the distribution of political power in society? The new constitutional court in Costa Rica allows the authors to analyze the effects of judicial reform on the capacity of politically marginalized groups to safeguard their constitutional rights. Particular attention is paid to homosexuals, AIDS patients, and labor unions. The authors argue that it was not the establishment of the court as such but rather the specific rules regulating access to and cost of approaching the court that enabled marginalized groups to push for their rights and effectively circumvent the traditional policy-making process. Although these groups did not win all their cases, they have nonetheless been able to achieve considerable success in the protection of their previously denied constitutional rights. The legal reform partially redistributed power in society from policy makers to social groups and individuals.
The Discreet Charm of Formal Institutions
Authors: Grzymała-Busse Anna
Published: February 2006

Why do some new democratic political politicians constrain themselves and reduce their discretion to extract resources from the state and the processes of privatization? Postcommunist democracies show surprising variation in the adoption of formal institutions of monitoring and oversight. These institutions regulate markets, empower citizen oversight, and police the use and distribution of state assets. These have arisen rapidly in some countries and with considerable delays in others. Accounts that link institutional creation to European Union imposition, initial bargaining, and parliamentary divisions do not fully explain the variation. Instead, in the nine consolidated democracies and free markets examined here, robust political competition triggered mechanisms of anticipatory institution building and moderation of government behavior.
Effects of Social Position on Societal Attributions of an Asymmetric Conflict
Authors: Montiel Cristina Jayme , Macapagal Maria Elizabeth J.
Published: February 2006

Traditionally, the study of peace and conflict has employed macro explanations such as social structure and state conditions. This article extends the discourse on peace and conflict by considering psychological conditions during a heated social conflict. The focus is on societal attribution, a cognitive process involving shared beliefs about the causes of societal events. The present study examines the effects of social positions on causal attributions in an asymmetric conflict that is taking place in the Philippines on the war-torn island of Mindanao. It was expected that causal attributions of the Mindanao war would differ between Christians and Muslims. Four hundred and thirty Muslims and Christians at Mindanao State University-Marawi stated their degree of agreement on belief statements about perceived intergroup inequality and ranked the three most important causes of the conflict in Mindanao. Results indicated that power inequality between groups is perceived only by the disadvantaged Muslim group, while members in the dominant social position were not sensitized to systemic issues. Findings also indicated intergroup disagreements about the causes of the war. The marginalized Muslims believed that structural problems, namely, displaced and landless Bangsa Moro (Muslim Nation) and loss of rights to self-determination were important origins of the conflict. On the other hand, the dominant Christian group attributed the Mindanao conflict to person-related causes like corruption of the mind and moral fiber, as well as sociocultural discrimination. Implications for attribution theory and the practice of peacemaking in asymmetric conflicts are discussed.