bluuebunny/crossref_metadata_2025 huggingface dataset:
Characteristics of Sediment and Organic Carbon Export from Pristine Boreal Forest Watersheds
Authors: Naiman Robert J.
Published: April 2009

Estimates of the amount of material moving annually from terrestrial ecosystems to the ocean are largely based on an incomplete understanding of events occurring throughout the hydrologic year, and only a vague comprehension of in-stream processes controlling that export. Discharge, suspended sediment, particulate organic matter (POM; > 0.5 μm), dissolved organic carbon (DOC; <0.5 μm diameter), and the percentage of organic matter were measured from 1979 to 1981 in five pristine Quebec streams: First Choice Creek (1st order; watershed area: 0.25 km2), Beaver Creek (2nd order; 1.83 km2), Muskrat River (5th order; 204 km2), Matamek River (6th order; 673 km2), and the Moisie River (9th order; 19 871 km2). All streams, with the exception of First Choice Creek, have a strong spring freshet when 43–55% of the annual discharge occurs. By describing sediment and organic carbon export throughout the annual hydrologic cycle, 1 showed that during the 2-mo spring freshet 71–92% of the annual sediment load is exported but only 59–65% of the annual POM load, and only 47–51% of the annual DOC load. Sediment yield is relatively constant between watersheds (1.5–7.6 g∙m−2∙yr−1), as is POM export (1.0–6.7 g ash-free dry-weight [AFDW]∙m−2∙yr−1); however, export DOC varies from 3.1 g C∙m−2∙yr−1 in First Choice Creek to 48.4 g C∙m−2∙yr−1 in Beaver Creek. There appears to be rapid loading of carbon between 1st- and 2nd-order streams in boreal forests, followed by biological and physical processing as watershed area increases. Thus, for the Moisie River watershed, export of total organic carbon (TOC) is reduced to only 4.7 g C∙m−2∙yr−1. Export of coarse particulate organic matter (> 1 mm) is negligible (normally < 0.1 mg∙L−1), as is oxidation of the suspended load (< 0.5%∙d−1). Effects of summer storms, natural diel variations, and depth of sample from the water column are shown to have a minimal influence on concentrations. Rating curves (kg∙d−1 vs. discharge) are developed to estimate the annual yield of sediment, POM, and DOC, and to evaluate long-term variations. From the results I suggest that in-stream processing and retention devices exert considerable control over the quantity and nature of suspended organic material. Physical processes such as the discharge regime and stream power are relatively less important in determining organic concentrations, but more important in determining sediment concentrations.Key words: seston, carbon, sediment, boreal forest, watershed, river, stream, export
Use of Box and Line Plots to Assess Fish Ventilatory Behavior in Biological Monitoring Systems
Authors: Sydor W. J. , Miller III W. R. , Cairns Jr. J. , Gruber D.
Published: April 2009

Ventilatory signals from 12 bluegill (Lepomis macrochirus) sunfish were collected with the aid of an on-line minicomputer as part of a biological monitoring system. Our results from three experiments demonstrate a potential for applying these graphic techniques to on-line biomonitoring systems.Key words: biological monitoring, ventilatory behavior, biomonitoring, bluegill sunfish, breathing, water quality, box plots, line plots
Ichthyophthiriasis: Immersion Immunization of Rainbow Trout (Salmo gairdneri) Using Tetrahymena thermophila as a Protective Immunogen
Authors: Wolf Ken , Markiw Maria E.
Published: April 2009

Four-hour bath exposure of rainbow trout (Salmo gairdneri) fry to Tetrahymena thermophila (1–2 × 105 cells/mL), or to the sheared cilia from an equal number of cells, followed by a holding time of 8–10 wk, provided protection against a challenge Ichthyophthirius multifiliis infection that killed 65% of nonimmunized controls. A holding time of 6 wk or less provided proportionally less protection. When, at the conclusion of the work, a chance infestation with Ichtyobodo necatrix occurred, surviving immunized fish were more resistant than nonimmunized fish. In contrast to the protection obtained against I. multifiliis with either whole cells or cilia, survivors of I. necatrix were more numerous among fish that were exposed to whole cell antigen than among those exposed to sheared cilia.Key words: Ichthyophthiriasis, Ichthyophthirius multifiliis, Tetrahymena thermophila, immunization, Ichtyobodo necatrix, rainbow trout, Salmo gairdneri; immunity, immune response, ciliates
MULTIPOLE MATRIX ELEMENTS ν FOR H-LIKE ATOMS, THEIR ASYMPTOTICS AND APPLICATIONS (AS β=1, n ≤ 4, n' ≤ 10)
Authors: TARASOV V. F.
Published: April 2009

This article deals with the connection between multipole matrix elements ν for H-like atoms and new properties of Appell's function F2(x,y) to the vicinity of the singular point (1, 1), where ν is the so-called "auxiliary" parameter of Heun-Schrödinger's radial equation, |1 - ν| = o(1), [Formula: see text] is the "effective" nuclear charge. Exact numerical values for the dipole matrix elements, the average oscillator strengths, the transition probabilities and the line intensities, as n ≤ 4 and n' ≤ 10, in the form of regular rational fractions are given (in Tables 1–4), that make more precise the well-known Tables 13–16 by Hans A. Bethe.
FIRST-PRINCIPLES STUDY OF THE MIGRATION OF HELIUM IN TUNGSTEN
Authors: YANG LI , LIU HANKUI , ZU XIAOTAO
Published: April 2009

First-principles calculations based on density functional theory (DFT) within the generalized gradient approximation (GGA) have been carried out to study the migration of helium in tungsten. The results show that helium interstitial jump directly between two tetrahedral sites with very low migration energy. The migration manner of interstitial He is related to the configuration of the host metal. Furthermore, the dissociation energy of a substitutional helium atom from a vacancy has been calculated from first-principles.
HYDROGENIC IMPURITY IN A QUANTUM WIRE: EFFECT OF DIFFERENT MASSES OF WIRE AND BARRIER
Authors: MIKHAIL I. F. I. , EL-SAYED S. B. A.
Published: April 2009

A variational calculation is given within the effective mass approximation of the binding energy of a hydrogenic donor impurity located on the axis of an infinitely long circular quantum well wire. A uniform magnetic field is applied along the axis of the wire. The different effective masses of the wire and the barrier are taken into consideration. This has not been done hitherto in the presence of the magnetic field. New analytical expressions for the electron energy levels and the binding energies of the hydrogenic impurity in the ground and the first four excited states have been derived.

Moreover, the form of the binding energy reported in earlier works in the special case of zero magnetic field has been amended. A new form of the trial wavefunction has also been introduced. It has the advantage of satisfying the required boundary conditions in the case of different masses of the wire and barrier, and thus it resembles the exact solution in this respect. The new form of the trial wavefunction has been applied to the case of the ground state. It has improved the results of binding energy considerably as they tend to approach the exact solution from below.
SOLVING THE KdV-BURGERS-KURAMOTO EQUATION BY A COMBINATION METHOD
Authors: XIE YUANXI , ZHU SHUHUA , SU KALIN
Published: April 2009

Based on the analysis on the characteristics of the KdV equation, Kuramoto-Sivashinsky equation and KdV-Burgers-Kuramoto equation, a combination method is proposed to construct the explicit exact solutions for the KdV-Burgers-Kuramoto equation by combining with those of the KdV equation and Kuramoto-Sivashinsky equation. As a result, many explicit exact solutions to the KdV-Burgers-Kuramoto equation are successfully derived by this approach.
PHOTOIONIZATION CROSS-SECTION AND OSCILLATOR STRENGTH OF HYDROGENIC IMPURITIES IN ZnS/SiO2 QUANTUM DOTS
Authors: YILMAZ SAİT , ŞAFAK HALUK
Published: April 2009

In this study, the photoionization cross-section and oscillator strength for the intersubband electronic transitions associated with an on-center impurity in the ZnS / SiO 2 spherical quantum dot have been calculated. The effects of dot radius, the normalized photon energy and the potential barrier height on the cross-section have been investigated. In the calculations, both the infinite and finite confinement cases have been considered.
SWAPPING BETWEEN TWO PAIRS OF NONORTHOGONAL ENTANGLED COHERENT STATES
Authors: PRAKASH H. , CHANDRA N. , PRAKASH R. , SHIVANI
Published: April 2009

We propose a scheme of swapping between two pairs of nonorthogonal entangled coherent states using a beam splitter, two phase shifters and photon counting measurements. We find that an almost perfect swapping is possible for an appreciable mean number of photons.
EFFECT OF EXCESS BISMUTH ON THE SYNTHESIS OF BISMUTH SILICATE (Bi4Si3O12) POLYCRYSTALS
Authors: KAEWKHAO J. , UDOMKAN N. , CHEWPRADITKUL W. , LIMSUWAN P.
Published: April 2009

In this study, the effect of bismuth content on the crystal structure and morphology of bismuth silicate ( BSO:Bi 4 Si 3 O 12) polycrystals were investigated with X-ray diffraction (XRD) analysis and scanning electron microscope (SEM). BSO materials have been successfully prepared by the solid-state reaction. The BSO phase was crystallized at 950°C for 12 h. In summary, 10% of excess bismuth was found to be the optimum composition with respect to crystallization, morphology, and grain size.
EFFECT OF PRESSURE ON SPONTANEOUS POLARIZATION AND TILT ANGLE IN FERROELECTRIC LIQUID CRYSTAL DOBAMBC
Authors: SINGH ABHILASHA , SINGH SHRI
Published: April 2009

Using a thermodynamic model based on the generalized Landau free-energy density expansion, we investigate the influence of hydrostatic pressure on the spontaneous polarization and tilt angle of ferroelectric chiral smectic C (Sm C*) phase near the Sm A–Sm C* transition in a ferroelectric mesogen DOBAMBC. It is shown that the pressure dependence of the tilt angle, spontaneous polarization and Sm A–Sm C* transition temperature (Tc) can be described in terms of four pressure-dependent Landau coefficients: two achiral coefficients a and b and two chiral coefficients Λ and d. The pressure dependence of the parameter a is due to the pressure-dependent Tc. With the increasing pressure, the stability of the Sm C* phase decreases. A close agreement between theory and experiment is found.
ROOM TEMPERATURE FERROMAGNETISM IN Mn DOPED ZnO SEMICONDUCTOR
Authors: SINGHAL R. K. , DOLIA S. N. , DHAWAN M. S. , GAUR S. K. , KUMAR SUDHISH , XING Y. T. , SAITOVITCH ELISA , GARG K. B.
Published: April 2009

Following the theoretical prediction of ferromagnetism in Mn - and Co -doped ZnO , there has been an immense experimental search for dilute semiconductors that show ferromagnetic ordering above room temperature, and several workers have reported ferromagnetism in bulk samples as well as in thin films of these materials. Mn -doped ZnO is the key material in this regard, which has been, in the recent past, shown to exhibit such magnetic properties. Many more such attempts have either led to failure or to a much lower Tc, and there have been a lot of confronting reports casting considerable doubts on the magnetism in this system. In order to shed some light, we have prepared and characterized dilute Mn -doped (2 and 4%) ZnO pellets. SQUID measurements confirm that the 2% sample shows above room temperature ferromagnetic ordering, the ferromagnetic contribution coming mainly from the bulk. The ordering gets completely quenched for 4% Mn doping. Upon cooling down, the 2% Mn doped sample showed further enhancement in magnetic properties appreciably. On the other hand, the 4% sample did not show any ferromagnetic ordering, even down to 5 K, and has been found to retain the paramagnetic character.
EXACT SOLUTIONS IN A SPATIALLY ANISOTROPIC QUANTUM SPIN LADDER MODEL HAVING TWO- AND FOUR-SPIN EXCHANGE INTERACTIONS
Authors: BARRY J. H. , COHEN J. D. , MEISEL M. W.
Published: April 2009

We consider a two-leg S=1/2 quantum spin ladder model with two-spin (intra-rung) and four-spin (inter-rung) Heisenberg exchange interactions and a uniform magnetic field. Exact mappings are derived connecting the partition function and correlations in the three-parameter quantum model to those known in a two-parameter Ising chain. The quantum phase diagram of the ladder magnet is determined. Static correlations provide pertinent correlation lengths and underlie spatial fluctuation behaviors at arbitrary temperatures, including quantum fluctuations at absolute zero. Dynamic correlations in zero field are used to obtain an exact solution for the inelastic neutron scattering function Sxx(q, ω) at all temperatures, explicitly yielding the elementary excitation spectrum.
CHARACTERIZATIONS OF THE CLASS OF FREE SELF-DECOMPOSABLE DISTRIBUTIONS AND ITS SUBCLASSES
Authors: SAKUMA NORIYOSHI
Published: April 2009

In this paper, we firstly characterize the class of free self-decomposable distributions as a class of limiting distributions of suitably normalized partial sums of free independent random variables. Secondly, we introduce nested classes between the class of free self-decomposable distributions and that of free stable distributions, characterize them and show that the limit of the nested classes coincides with the closure of the class of free stable distributions. All results here are analogues of the results known in classical probability theory.
MALLIAVIN CALCULUS FOR LIE GROUP-VALUED WIENER FUNCTIONS
Authors: MELCHER TAI
Published: April 2009

Let G be a Lie group equipped with a set of left invariant vector fields. These vector fields generate a function ξ on Wiener space into G via the stochastic version of Cartan's rolling map. It is shown here that, for any smooth function f with compact support, f(ξ) is Malliavin differentiable to all orders and these derivatives belong to Lp(μ) for all p > 1, where μ is Wiener measure.
SPECTRA AND BOUND STATES OF THE ENERGY OPERATOR OF TWO-MAGNON SYSTEM IN A NON-HEISENBERG FERROMAGNET WITH SPIN S = 3/2 AND NEAREST-NEIGHBOR INTERACTIONS
Authors: TASHPULATOV S. M.
Published: April 2009

We consider a two-magnon systems in an ν-dimensional isotropic non-Heisenberg ferromagnet with spin value S = 3/2 and nearest-neighbor interactions. Spectrum and bound states (BS) of the system for all values of full quasi-momentum Λ, and for arbitrary value of lattice dimensionality ν, and for all values of Hamiltonian parameters are investigated. We show that (i) for arbitrary ν ≥ 2 and for full quasi-momentum in the form Λ = (Λ1; Λ2; … ;Λν) = (Λ0;Λ0; …; Λ0) the change of energy spectrum of the system is similar to that observed in the case of ν = 1. In this case the operator [Formula: see text] with J + J1 - 23J2 ≠ 0 has only one additional BS. (ii) The energy z of this additional BS is degenerate ν - 1 times. (iii) If Λ ≠ (Λ0;Λ0;…;Λ0), we show the existence no more 2ν + 1 bound states in the system in ν-dimensional lattice.
GIBBS MEASURES WITH DOUBLE STOCHASTIC INTEGRALS ON A PATH SPACE
Authors: BETZ VOLKER , HIROSHIMA FUMIO
Published: April 2009

We investigate Gibbs measures relative to Brownian motion in the case when the interaction energy is given by a double stochastic integral. In the case when the double stochastic integral is originating from the Pauli–Fierz model in nonrelativistic quantum electrodynamics, we prove the existence of its infinite volume limit.
COMPLEMENTARITY AND THE ALGEBRAIC STRUCTURE OF FOUR-LEVEL QUANTUM SYSTEMS
Authors: PETZ DÉNES , SZÁNTÓ ANDRÁS , WEINER MIHÁLY
Published: April 2009

The history of complementary observables and mutual unbiased bases is shortly reviewed. A characterization is given in terms of conditional entropy of subalgebras due to Connes and Størmer. The extension of complementarity to noncommutative subalgebras is considered as well. Possible complementary decompositions of a four-level quantum system are described and a characterization of the Bell basis is obtained: The MASA generated by the Bell basis is complementary to both M2(ℂ) tensor factors.
Technological Change and the Wealth of Nations
Authors: Gancia Gino , Zilibotti Fabrizio
Published: April 2009

We discuss a unified theory of directed technological change and technology adoption that can shed light on the causes of persistent productivity differences across countries. In our model, new technologies are designed in advanced countries and diffuse endogenously to less developed countries. Our framework is rich enough to highlight three broad reasons for productivity differences: inappropriate technologies, policy-induced barriers to technology adoption, and within-country misallocations across sectors due to policy distortions. We also discuss the effects of two aspects of globalization, trade in goods and migration, on the wealth of nations through their impact on the direction of technical progress. By doing so, we illustrate some of the equalizing and unequalizing forces of globalization.
Chemotaxis-Like Regulatory Systems: Unique Roles in Diverse Bacteria
Authors: Kirby John R.
Published: April 2009

Bacteria sense the chemical world using a variety of mechanisms that include the frequently described two-component system (TCS), which comprises a sensor kinase and response regulator, to regulate gene expression in response to environmental cues. One of the best and most widely studied versions of the TCS is the system that controls chemotaxis in Escherichia coli. The chemotaxis machinery includes components not found in other TCS to regulate motility and is therefore an exception to the rule for two-component signaling. The hallmark feature of the chemotaxis system is the presence of an adaptation module in which the sensor receptor protein is posttranslationally modified to attenuate ligand-induced signaling, a mechanism not yet identified for the more widely distributed prototypical TCS. More recently, variations on the chemotaxis system itself have been identified and they are termed chemosensory systems and are the subject of this review. Extensive research has provided a perspective on TCS signaling and indicates that variation and diversity for the standard two-component system are predominant in the microbial world.
Role of cardiopulmonary and carotid sinus baroreceptors in regulating renal sympathetic nerve activity during water immersion in conscious dogs
Authors: Miki Kenju , Yoshimoto Misa , Hayashida Yoshiaki , Shiraki Keizo
Published: April 2009

The aim of the present study was to investigate how loading of cardiopulmonary baroreceptors induced by water immersion (WI) modifies baroreflex control of renal sympathetic nerve activity (RSNA) in conscious dogs. Nine dogs were chronically instrumented for measuring carotid sinus nerve activity (CSNA), RSNA, carotid arterial (Pca), and central venous (Pcv) pressures. The stimulus-response relationships of Pca-CSNA and Pca-RSNA were determined simultaneously in the same dog by changing Pca using rapid intravenous infusions vasoactive drugs during pre-WI and WI. WI increased central venous pressure significantly ( P < 0.05) by 10.4 mmHg. WI shifted the Pca-RSNA curve acutely leftward compared with the pre-WI period, which was associated with significant ( P < 0.05) decreases in the saturation pressure by 39.0 mmHg and operating range by 43.1 mmHg. WI relocated the operating pressure to near the saturation pressure, where the gain was low. The Pca-CSNA curve obtained during WI was identical to that obtained during pre-WI period. These results suggest that the shift in baroreflex control of RSNA could be attributed to the inhibitory influence of the cardiopulmonary mechanoreceptor loading and not by the resetting of carotid baroreceptors per se.
Facilitatory Actions of Serotonin Type 3 Receptors on GABAergic Inhibitory Synaptic Transmission in the Spinal Superficial Dorsal Horn
Authors: Fukushima Teruyuki , Ohtsubo Toshiki , Tsuda Masayuki , Yanagawa Yuchio , Hori Yuuichi
Published: April 2009

Analgesic effects of serotonin (5-hydroxytryptamine [5-HT]) type 3 (5-HT3) receptors may involve the release of γ-aminobutyric acid (GABA) in the spinal dorsal horn. However, the precise synaptic mechanisms for 5-HT3receptor-mediated spinal analgesia are not clear. In this study, we investigated whether GABAergic neurons in the superficial dorsal horn (SDH) express functional 5-HT3receptors and how these 5-HT3receptors affect GABAergic inhibitory synaptic transmission in the SDH, by using slice preparations from adult glutamate decarboxylase 67–green fluorescent protein (GAD67-GFP) knock-in mice. Tight-seal whole cell recordings from GFP-positive and -negative neurons showed that 5-HT3receptor-specific agonist 2-methyl-serotonin (2-Me-5-HT) induced inward currents in a substantial population of both GFP-positive and -negative neurons. Additionally, we confirmed expression of 5-HT3receptors in both types of neurons by single-cell reverse transcription–polymerase chain reaction (RT-PCR) analysis. Further, GABAAreceptor-mediated inhibitory postsynaptic currents (IPSCs)—both those evoked by electrical stimulation and those occurring spontaneously in tetrodotoxin (i.e., miniature IPSCs [mIPSCs])—were recorded from GFP-negative neurons. 2-Me-5-HT increased the amplitude of the evoked IPSCs and the frequency of mIPSCs. The amplitude of mIPSCs was not affected by 2-Me-5-HT, suggesting that 5-HT augments GABAergic synaptic transmission via presynaptic mechanisms. The present observations indicate that 5-HT3receptors are expressed on both somadendritic regions and presynaptic terminals of GABAergic neurons and regulate GABAAreceptor-mediated inhibitory synaptic transmission in the SDH. Taken together, these results provide clues for the underlying mechanisms of the antinociceptive actions of 5-HT3receptors in the spinal dorsal horn.
Executive Functioning at Ages 5 and 7 Years in Children with Prenatal Cocaine Exposure
Authors: Eyler Fonda Davis , Warner Tamara Duckworth , Behnke Marylou , Hou Wei , Wobie Kathleen , Garvan Cynthia Wilson
Published: April 2009

This prospective longitudinal study evaluated the effect of prenatal cocaine exposure (PCE) on executive functioning in 5- and 7-year-old children. In total, 154 pregnant cocaine users, identified by urine toxicology and structured interviews, were matched to 154 nonusers. Children were assessed by certified masked evaluators, and caregivers were interviewed by experienced staff during home visits. In approximately 90% of the surviving sample tested at ages 5 and 7 years, structural equation modeling demonstrated that an increased head circumference at birth (adjusted for gestation) significantly predicted better performance on executive functioning, and that PCE was indirectly related to executive functioning through its significant negative effect on head circumference at birth. At age 5 years, quality of environment also predicted executive functioning, and the R2 for the total model was 0.24. At 7 years, caregiver functioning predicted quality of environment, which in turn was positively related to executive functioning, and girls had better executive functioning. The total model at age 7 years accounted for 30% of the variance in executive functioning.
Acute and Transient Podocyte Loss and Proteinuria in Preeclampsia
Authors: Aita Kumi , Etoh Mio , Hamada Hiromi , Yokoyama Chie , Takahashi Ayuko , Suzuki Taisei , Hara Masanori , Nagata Michio
Published: April 2009

Glomerular podocytes are known to regulate proteinuria and podocyturia correlated with proteinuria. Podocyturia, the urinary excretion of viable podocytes (glomerular epithelial cells), has been associated with proteinuria in preeclampsia. This study is the first to investigate the time course alterations of podocyturia in patients with preeclampsia (11 cases) and normotensive pregnant women (45 cases). Urinalysis was performed at 35 weeks of gestation, 4 days after delivery, and 1 month after delivery. In patients with preeclampsia, podocyturia was evident at 35 weeks of gestation and 4 days after delivery, while proteinuria had already decreased at 4 days after delivery. At 1 month after delivery, almost no patients exhibited podocyturia. In control cases, proteinuria was not significant throughout the study period. However, 9 of the 45 controls exhibited transient and mild podocyturia at 4 days after delivery without proteinuria or hypertension. Statistics indicated a correlation between urinary podocyte number and blood pressure, but not with proteinuria. In conclusion, podocyturia in preeclampsia is transient and almost synchronous with heavy proteinuria. The results suggest that acute podocyte loss implicates podocyturia as the possible mechanism of proteinuria in women with preeclampsia.
Impact of Obesity on IgA Nephropathy: Comparative Ultrastructural Study between Obese and Non-Obese Patients
Authors: Tanaka Mari , Yamada Sachiko , Iwasaki Yukako , Sugishita Takeshi , Yonemoto Satomi , Tsukamoto Tatsuo , Fukui Satoshi , Takasu Kosho , Muso Eri
Published: April 2009

Background: The pathological role of obesity in the progression of glomerular lesions has rarely been studied in primary glomerular diseases. The purpose of this study is to investigate the influence of non-diabetic obesity on clinicopathological findings in IgA nephropathy. Methods: 74 patients with biopsy-proven IgA nephropathy were retrospectively divided into two groups according to the criteria for obesity in Japan: non-obese group (group N: n = 50) with BMI <25 kg/m2, and obese group (group O: n = 24) with BMI ≥25 kg/m2. Clinical and pathological data at the time of renal biopsy were analyzed. Moreover, the outcome of proteinuria in patients treated with angiotensin-converting enzyme inhibitors (ACE-I) or angiotensin II receptor blockers (ARB) was evaluated in different groups after a 1-year follow-up. Results: Urinary protein excretion was significantly greater in the obese group compared to normal-weight patients (p < 0.05). There was no significant difference in the prevalence of hypertension and hyperlipidemia. By light microscopy, the obese group showed significantly larger glomerular size (p < 0.0001). On the other hand, the severity of mesangial matrix expansion and crescent formation revealed no difference between the two groups. By electron microscopy, glomerular basement membrane (GBM) thickness was significantly increased in obese patients (p < 0.001). Among 61 patients who were followed up for 1 year in our institute, 15 patients were treated with ACE-I or ARB without steroids. ACE-I or ARB treatment without steroids tended to reduce proteinuria in the obese patients, but this change did not achieve statistical significance. Conclusions: In IgA nephropathy, obesity induces not only glomerular enlargement but also ultrastructural modification of GBM, which would contribute to increase proteinuria.
Kidney Disease Is a Negative Predictor of 30-Day Survival after Acute Ischaemic Stroke
Authors: Brzosko Szymon , Szkolka Tomasz , Mysliwiec Michal
Published: April 2009

Background/Aims: Impaired renal function is a strong risk factor for cardiovascular diseases and worsens a patient’s prognosis. Renal dysfunction predicts mortality after acute stroke in the long term. On the other hand, in-hospital mortality after acute stroke is strongly associated with disorders of consciousness at the onset of stroke, severity of stroke, body temperature, blood sugar and some other comorbidities. The aim of the study was to analyze the possible role of renal dysfunction and/or signs of renal disease (proteinuria) on 30-day mortality after acute ischaemic stroke (AIS) based on the hospital medical records of one county. Methods: Medical records of 312 consecutive patients admitted to Ostrołęka County Hospital (Department of Neurology) between March 2000 and October 2002 for AIS were retrieved retrospectively to determine factors influencing 30-day survival. None of patients received thrombolytic therapy. Results: Among the patients analyzed, 74 (23.7%) died during the 30-day period. In a simple Cox proportional hazards regression model, negative predictive factors were: older age, higher pulse rate, lower estimated glomerular filtration rate (eGFR), proteinuria, elevated plasma glucose level, diabetes mellitus, atrial fibrillation and chronic heart failure. In a multivariate analysis, independent negative predictors of 30-day morbidity were: age hazard ratio (HR) 1.05 (95% CI 1.02–1.08), eGFR <60 ml/min HR 1.75 (95% CI 1.21–2.19), dipstick proteinuria HR 2.28 (95% CI 1.74–2.82) and plasma glucose level >100 mg/dl HR 2.96 (95% CI 2.22–3.70). Conclusion: The results of this study identify decreased eGFR and presence of dipstick proteinuria as a strong negative predictor of 30-day survival after AIS in patients not treated with thrombolytic agents.
Counselling Prior to Blood-Borne Virus Screening in Haemodialysis Patients: A Survey of Patient Experience and Opinion
Authors: Swoboda Peter , Modi Alpa , Bhandari Sunil
Published: April 2009

Background: Patients with end-stage renal disease receiving renal replacement therapy are at higher risk of infection with hepatitis B, C and HIV viruses as compared to the general population. Early screening, education and vaccination potentially reduce the risk of acquiring these viruses and therefore future morbidity and mortality. We have sought to establish the opinions, perceptions and understanding of patients regarding the routine testing for blood-borne viruses (BBV) to help improve testing strategies. Methods: An anonymised survey was conducted in all local dialysis patients that asked their understanding, knowledge and opinions on BBV screening and counselling. Results: 55.3% (167/302) of all local dialysis patients responded to the survey. 55.1% of these patients knew that they had been screened for BBV and only 12.6% indicated that they had received any counselling prior to testing. However, 74.3% answered that they would be happy to be tested without consent or counselling. Conclusion: The majority of the patients had not received adequate information regarding BBV screening, but most were content with regular viral screening after initial counselling and consent. Information during pre-dialysis sessions may be an appropriate way of educating patients about the importance of BBV.
Immunoglobulin G4-Associated Cholangitis: One Variant of Immunoglobulin G4-Related Systemic Disease
Authors: Alderlieste Yasser A. , van den Elzen Bram D.J. , Rauws Erik A.J. , Beuers Ulrich
Published: April 2009

IgG4-associated cholangitis (IAC) is a recently defined disease entity which shares a number of clinical, biochemical, and radiological features with primary sclerosing cholangitis (PSC). In contrast to PSC, IAC responds to immunosuppressive treatment, is not associated with inflammatory bowel disease, and mainly affects elderly men above the age of 60 years. Today, IAC is regarded as one variant of IgG4-related systemic disease (ISD) of which autoimmune pancreatitis (AIP) is the best studied organ manifestation. The diagnosis of IAC is based on biochemical, radiological and histologic features, among which elevated serum levels of IgG4, extra- and intrahepatic biliary strictures as visualized by cholangiography, multifocal IgG4-rich lymphoplasmacytic sclerosing infiltrations in liver and bile duct tissue, and association with AIP are of key importance. This review aims at summarizing clinical features, diagnostic criteria, therapeutic strategies and most recent insights in the pathophysiology of IAC and other organ manifestations of ISD.
Computer-Assisted Microaneurysm Turnover in the Early Stages of Diabetic Retinopathy
Authors: Bernardes Rui , Nunes Sandrina , Pereira Ivânia , Torrent Teresa , Rosa Andreia , Coelho Dalila , Cunha-Vaz José
Published: April 2009

Purpose: To assess the reliability of microaneurysm turnover, computed from color fundus photographs, in evaluating diabetic retinopathy in patients with type 2 diabetes and nonproliferative retinopathy. Methods: A new method (MA-Tracker) was developed to count microaneurysms by mapping their locations through image co-registration. To compute the reliability of microaneurysm turnover, 3 different graders were asked to earmark microaneurysms on the same set of color fundus photographs. Results: The total numbers of microaneurysms earmarked in each of 5 visits suggest that microaneurysms remain stable over time (p ≥ 0.138). However, an analysis of each microaneurysm showed that only 29.4% remained at the same location. By computing the formation and disappearance rates of microaneurysms (2.3 and 1.7 microaneurysms/year, respectively), a significant turnover of microaneurysms was found. Conclusions: The formation and disappearance rates of microaneurysms obtained from color fundus photographs using MA-Tracker show very good agreement between different graders, and can be used as indicators of microaneurysm turnover in the initial stages of diabetic retinopathy.
Branch Retinal Vein Occlusion: Classification and Treatment
Authors: Battaglia Parodi Maurizio , Bandello Francesco
Published: April 2009

Branch retinal vein occlusion (BRVO) refers to a heterogeneous group of disorders with different clinical aspects, courses, and probably therapy. Depending on the site of the arteriovenous crossing, we can roughly divide BRVO into 3 main groups: major BRVO, hemispheric retinal vein occlusion, and macular BRVO. Main treatment options include laser treatment, corticosteroid administration, anti-VEGF drugs, and sheathotomy with or without vitrectomy. Laser photocoagulation, as demonstrated by the Branch Vein Occlusion Study, represents the gold standard for the treatment of macular edema and ocular neovascularization following BRVO. The limited functional outcomes achievable by means of laser treatment have prompted researchers to try alternative options, with varying results. The recent introduction of combined therapies for macular edema may provide a superior approach in an attempt to improve and stabilize visual acuity over a long-term follow-up.
Modeling Familial Amyloidotic Polyneuropathy (Transthyretin V30M) in Drosophila melanogaster
Authors: Berg Ina , Thor Stefan , Hammarström Per
Published: April 2009

Background/Aims: Transthyretin (TTR) is a prevalent plasma and cerebrospinal fluid protein associated with sporadic and heritable amyloidosis. TTR amyloidosis is linked to a vast number of mutations with varying phenotype, tissue distribution and age of onset. The most prevalent mutation associated with familial amyloidotic polyneuropathy (FAP) is the V30M mutation. Studies of transgenic mouse models of TTR V30M FAP have been hampered by variable phenotype, low disease penetrance, and slow onset. Methods/Results: To model TTR-associated amyloid disease in the Drosophila model system, transgenic Drosophila were generated, expressing wild-type (wt) TTR or TTR V30M, associated with sporadic senile systemic amyloidosis (SSA) and inherited FAP, respectively. We found that expression of FAP-associated TTR V30M mutant in the nervous system resulted in reduced lifespan and in reduced climbing ability indicating neurological impairment, whereas expression of TTR wt showed a milder phenotype. Congo red staining of the Drosophila brain shows positive amyloid binding in the aged TTR V30M flies. Extensive brain vacuole formation was evident for the aged TTR V30M flies, whereas a milder phenotype was shown by the TTR wt flies. In addition, expression of TTR V30M in the eye leads to tissue damage, including rough eye, morphological changes and fibrous deposition. Conclusion: Our results suggest that Drosophila is a promising complementary system for studies of TTR-associated amyloid diseases.
Activation of Signal Transducer and Activator of Transcription-3 in the Spinal Cord of Sporadic Amyotrophic Lateral Sclerosis Patients
Authors: Shibata Noriyuki , Kakita Akiyoshi , Takahashi Hitoshi , Ihara Yuetsu , Nobukuni Keigo , Fujimura Harutoshi , Sakoda Saburo , Sasaki Shoichi , Iwata Makoto , Morikawa Shunichi , Hirano Asao , Kobayashi Makio
Published: April 2009

Background: Neuroinflammation has been implicated in the pathomechanism of amyotrophic lateral sclerosis (ALS). It is known that signal transducer and activator of transcription-3 (STAT3) is a proinflammatory transcription factor. However, it remains to be determined whether STAT3 is involved in ALS. Objective: To test the hypothesis that STAT3 may be upregulated, activated, or both in the spinal cord of ALS patients. Methods: We performed immunohistochemical, immunoblot and densitometric analyses of total STAT3 (t-STAT3) or phosphorylated active form of STAT3 (p-STAT3) in spinal cords obtained at autopsy from 10 sporadic ALS patients and 10 age-matched control subjects. Results: On sections, p-STAT3 immunoreactivity was localized in the nucleus as well as the cytoplasm of almost all activated microglia in the ALS cases, while it was detectable in a few resting microglia in the control cases. On blots, densitometric p-STAT3 levels in nuclear protein extracts significantly increased in the ALS group compared with the control group, although there was no significant difference in densitometric t-STAT3 levels in cytosolic protein extracts between the two groups. Additionally, there was no significant relationship between the nuclear p-STAT3 levels in the ALS cases and the clinical phenotypes, age at death, or disease duration. Conclusion: The present results suggest that persistent activation and nuclear translocation but not upregulation of STAT3 occurs in ALS spinal cord microglia, which may regulate inflammatory activity.
Assay with Chromogenic Substrates of in vivo Activated Proteases
Authors: Fässler Hubert , Duckert François , Marbet German A.
Published: April 2009

The proteolytic enzymes of the coagulation and fibrinolysis systems as well as others such as kalhkrein, activated under pathological conditions can be determined directly, without manipulations of the plasmas, with the synthetic chromogenic substrates. With these substrates it is possible to follow the protease activity in disseminated intravascular coagulation, during thrombolysis and under other conditions. The lack of absolute substrate specificity makes it impossible to identify the activated proteases.
Current Concepts on Action of Synthetic Thrombin Inhibitors
Authors: Geratz Dieter , Tidwell Richard
Published: April 2009

The development of synthetic inhibitors of thrombin and of related arginine-specific esteroproteases is reviewed. The superiority of bis- and tris-benzamidines over benzamidine is discussed and related to the presence on the enzyme of secondary binding sites beyond the specificity pocket. It is demonstrated that inhibitors with marked specificity for a single enzyme can be produced, and with the help of such selective compounds it is shown that inhibition of factor Xa is more significant for overall anticoagulant effect than inhibition of thrombin.
Pharmacological Control of Hyperproteolytic States in Blood by Synthetic Inhibitors of Serine Proteinases
Authors: Markwardt Fritz
Published: April 2009

Proteolytic enzymes participate extensively in coagulation, fibrinolysis, kininogenesis, and complement activity. Synthetic low molecular weight inhibitors of these enzymes which belong to the group of serine proteinases allow pharmacological control of these processes. The development of such inhibitors and their therapeutic importance are reported, especially on the pattern of benzamidine derivatives.
Rigidity of Red Cells in Essential Hypertension
Authors: Dintenfass L. , Girolami A.
Published: April 2009

Both viscosity of blood and the rigidity of red cells are of consequence in the mechanism of hypertension. While the details of this mechanism are still elusive, the evidence presented might open the way for a wider inquiry into the role of blood rheology in hypertension.
Regions of Constantly Increased Plasminogen Activator Activity along the Intima of the Normal Aorta
Authors: Smokovitis Athan.
Published: April 2009

Histochemical studies of the aorta in newborn, young, and adult rats showed that the intima in the branching regions and at the beginning of the branches has a constantly increased plasminogen activator activity in comparison with the nonbranching regions. The aortic valve also shows constantly increased activator activity. The intimal activator activity is variable in the nonbranching regions, depending on the age and the anatomical area of the aorta. In young rats (20–30 days), the overall plasminogen activator activity in the aortic intima is higher than in adult rats (2–4 months), while the activity is variable in newborn ratsi The intimal activator activity is generally higher in the thoracic aorta than in the abdominal aorta (in the nonbranching regions). The aortic wall has a low plasmin inhibitor capacity. The pattern of the endothelial plasminogen activator activity at different ages and anatomical areas of the aorta, in combination with the corresponding pattern of the aortic endothelial cell turnover, gives valuable information about the mechanism(s) of the production and normal (nonstressed) release of the endothelial plasminogen activator.
Platelet Adhesiveness in Ischemic Heart Disease
Authors: Aznar J. , Villa P. , Rueda E.
Published: April 2009

The adhesiveness of platelets to collagen and glass was studied ex vivo in groups of patients with ischemic heart disease (IHD) and acute myocardial infarction (AMI). Adhesiveness was increased to glass and normal to collagen in both groups of patients. No relation was found between reinfarction rate and adhesiveness in the acute stage of AMI. Electrophoretic mobility of platelets was the same in the AMI patients and a normal control group. It is suggested that the increased ‘retention’ of platelets in IHD patients might be due more to platelet hyperaggregation or to hypersensitivity to platelet aggregating agents than to altered adhesiveness.
The Effects of Albumin-Bound Unsaturated Fatty Acids on Platelets
Authors: Refsum Nina , Lowery Carol , Nordøy Arne
Published: April 2009

Unsaturated fatty acids (FA) were bound to human albumin in a molar ratio of 2 and were then added to platelet-rich plasma (PRP), increasing the total FA concentration by 1 mM. Separate FA and FA paired with di-homo-γ-linolenic acid (DHLA) and arachidon-ic acid (AA), respectively, were incubated with PRP for 5 and 90 min, and platelet aggregation and platelet factor 3 (PF3) activity were measured. DHLA inhibited adenosine-diphos-phate- and collagen-induced platelet aggregation after 5 min, an effect which was enhanced after 90 min. The effects of AA, which stimulated platelet aggregation and increased PF3 activity, were partially counteracted by DHLA after 90 min. When linoleic acid and AA were incubated with PRP in equimolar concentrations for 90 min, an inhibition of collagen-induced platelet aggregation was observed which was not observed after incubation with these FA separately. This study indicates that exogenous albumin-bound AA and DHLA may be used directly by the platelet cyclo-oxygenase pathway before significant incorporation into the platelet phosphoüpids has occurred.
Shape and Functional Properties of Human Platelets Washed with Acid Citrate
Authors: Patscheke Heinrih
Published: April 2009

Acid citrate pH 6.5 protects human platelets from activation during washing at room temperature. Platelets suspended in media containing citrate pH 6.5 have an extra-flat disc shape. Citrate at pH 6.5 also inhibits the ADP-induced shape change. When warmed to 37 °C and suspended into the test medium of pH 7.4, the washed platelets aggregate with low concentrations of ADP or epinephrine in the presence of fibrinogen and Ca2+. The morphological and functional quality of platelet concentrates (6 × 106 μl-1) stored in acid citrate pH 6.5 is maintained for at least 6 h at room temperature.
Study of Platelet Diameter Distribution in Patients with Valvular Heart Disease and with Prosthetic Heart Valve Replacement
Authors: Dumoulin M. , Tirmarche M. , Horellou M.H. , Acar J. , Samama M.
Published: April 2009

We have studied the platelet count and the megathrombocyte index (MI), or percentage of platelets that have a diameter greater than 2.9 μm, in 100 patients with valvular heart disease. The mean platelet count is significantly lower than in controls (p < 0.0005) and the MI is significantly increased (p < 0.01). No difference was observed in these two parameters according to the variety of the valvular heart disease. 45 of the same patients were studied after prosthetic heart valve replacement. Our results show a significant elevation of platelet count and a significant decrease of MI compared with the presurgical values in all groups except in the mitral one in which MI remains increased. This work demonstrates the presence of platelet abnormalities which reveal a compensated thrombo-cytolytic state in patients with valvular heart disease and its partial correction after aortic, but not mitral, valve replacement.
Reduced Platelet Factor X-Activating Activity
Authors: Cortellazzo S. , Colucci M. , Barbui T. , Dini E. , Semeraro N.
Published: April 2009

A recently described platelet coagulant activity, factor X-activating activity (FXAA), was studied in 33 patients with polycythaemia vera and in 5 with essential thrombocythaemia, in order to gain information about possible mechanisms responsible for the haemostatic disorders observed in myeloproliferative diseases. Other parameters of platelet function including bleeding time, spontaneous and ADP-, epinephrine- or collagen-induced platelet aggregation, serotonin content and malondialdehyde (MDA) production in response to thrombin, were investigated simultaneously. Compared to the range obtained from 27 control subjects (60–150%), FXAA was low in all 9 patients with bleeding complications (range: 5–39%), in 1 out of 7 patients with thrombotic manifestations (range: 38–200%) and in 9 out of 22 patients without symptoms (range: 38–500%). Only the bleeding group differed significantly from each of the others. Moreover, of all patients with reduced FXAA, those with bleeding could be clearly distinguished from those without such symptoms on the basis of the degree of the defect. Increased FXAA (above 150%) was found in 2 out of 7 thrombotic patients and in 2 out of 22 asymptomatics. MDA production was significantly lower in the haemorrhagic group and enhanced in the thrombotic one as compared to control subjects or asymptomatic patients. However, a large area of overlap was observed between the four groups. None of the other platelet function parameters studied (bleeding time, platelet aggregation, platelet serotonin content) correlated with the clinical type of haemostatic complication. Our results suggest a significant association between reduced
Plasmin Inhibitors in Different Fibrinolytic Treatment Patterns
Authors: Lasierra J. , Díez M. , Perera C. , Viladés E.
Published: April 2009

The variations of different antiplasmins were studied in a group of patients suffering from thromboembolic conditions and receiving three different regimens of throm-bolytic treatment with streptokinase and urokinase. The evaluation of the antiproteases was carried out by chromogenic substrate and radial immunodiffusion. The different administration patterns of the fibrinolytic agents were followed by a clear drop in fast antiplasmin and α2-macroglobulin, while α1-antitrypsin was increased. Antifhrombin-III activity was reduced while its protein rose in the intermittent treatment with streptokinase. In the conventional treatment with streptokinase, both the activity and the protein of antithrobin-III increased. With urokinase both the protein and the activity of antithrombin-III were slightly reduced. Plasminogen and fibrinogen decreased in the different regimens of thrombolytic treatment, being more evident in continuous administration of streptokinase.