bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelling phosphate‐sorption kinetics in acid soils
Authors: FREESE D. , VAN RIEMSDIJK W.H. , VAN DER ZEE S.E.A.T.M.
Published: August 2005

A model of P‐sorption kinetics was developed, that accounts for the dependency of reaction rate on concentration, sorbed P content, sorption maximum and time. The sorption phenomena predicted by the model agree with available observations in the literature. The model was tested with batch experiments for 17 acid top– and subsoils. The experiments revealed a significant correlation between the sorption maximum, Fm, and the sum of amorphous iron and aluminium in soils. Plotting the dimensionless P–sorption ratio, F(c, t)/Fm, which may be interpreted as the fractional saturation of the sorption capacity of a soil, against the natural logarithm of the exposure variable, I, gave S–shaped curves. Different parts of the S–shaped curve can be experimentally assessed, depending on the initial fractional saturation of the P–sorption capacity of soils. Apart from this dependency, one set of parameter values sufficed to describe the sorption kinetics of 10 different sandy top– and subsoils. For non–sandy soils, the parameter values differed and depended on the initial P content. The model enables extrapolation to long times, which is necessary for applications to field conditions.
Equilibrium adsorption of isoproturon on soil and pure clays
Authors: WORRALL F. , PARKER A. , RAE J.E. , JOHNSON A.C.
Published: August 2005

The adsorption of isoproturon on soil and pure clay minerals has been investigated as a means of understanding its mobility in soils. Measured adsorption coefficients are correlated with soil and clay mineral properties.

Soil organic matter controlled the adsorption of isoproturon at organic carbon contents exceeding 27 g kg−1, whereas at less than this threshold, clay mineral surfaces appeared to control adsorption. The effect of varying temperature suggests that adsorption of isoproturon is a physical process. From the comparison of the fits of linear, Freundlich, and Langmuir adsorption isotherms to the data, the adsorption is best described as a partition process.
Fate of particulate organic matter in soil aggregates during cultivation
Authors: BESNARD E. , CHENU C. , BALESDENT J. , PUGET P. , ARROUAYS D.
Published: August 2005

Particulate organic matter (POM) is a labile fraction of soil organic matter which is thought to be physically protected from biodegradation when within soil aggregates. We have developed a fractionation method to separate POM located outside stable soil macroaggregates (> 200 μm) and microaggregates (50–200 μm) from that within them, and applied it to a cultivation sequence of humic loamy soils. The natural abundance of 13C was used to determine the amounts of POM derived from forest and that derived from crop in the free and occluded fractions. In the forest soil the free and occluded POM fractions had the same composition, morphology and isotopic signature. On cultivation the amounts of POM decreased sharply. The loss of C in the POM from forest was mainly from POM outside the aggregates. The POM occluded within microaggregates was found to turnover slowly. This may be due either to its recalcitrant chemical nature or to its physical protection within microaggregates
Simulating soil deformation using a critical‐state model: II. Soil compaction beneath tyres and tracks
Authors: KIRBY J.M. , BLUNDEN B.G. , TREIN C.R.
Published: August 2005

A critical‐state finite element model was used to simulate compaction under single and dual tyres and tracks. The compaction involved deformations at three different scales, from small tyres with a contact area of about 70 cm2 (single tyre) supporting a load of about 50 kg, to large tyres of about 1.2 m2 (dual tyres) supporting a load of about 4500 kg. The predictions were compared with measured values for several different quantities. These included: rut depths; vertical displacement and shear strain: vertical stresses; and, void ratios and precompression stress measured on sampled soil cores. In general, the predictions and measurements agreed reasonably well. However, the agreement between prediction and measurement depended on the precision of measurements, soil disturbance, and the volume of soil involved in a measurement relative to the volume of soil influenced by the tyre or track. This study shows that the critical‐state finite element model is useful, offering insight into the compaction process, the dependence of compaction on soil strength and compressibility, and practical implications for soil management.
CD4+CD25+‐Regulatory T Cells from Mouse to Man
Authors: Wing K. , Suri‐Payer E. , Rudin A.
Published: August 2005

Immunological tolerance is one of the fundamental concepts of the immune system. During the past decade, CD4+CD25+‐regulatory T cells have emerged as key players in the development of tolerance to autoantigens as well as to foreign antigens. Still many questions remain illusive regarding the basic properties of CD4+CD25+‐regulatory T cells. This review aims to recapitulate some of the current understandings about the phenotype, function and clinical relevance of murine and human CD4+CD25+‐regulatory T cells.
Dexamethasone Induces IL‐10‐Producing Monocyte‐Derived Dendritic Cells with Durable Immaturity
Authors: Xia C.‐Q. , Peng R. , Beato F. , Clare‐Salzler M. J.
Published: August 2005

It is highly desirable that immature dendritic cells (DC) used for tolerance induction maintain steady immature state with predominant interleukin (IL)‐10 production. In this study, we attempted to develop DC with durable immaturity and other tolerogenic features by using dexamethasone (Dex). We found DC derived from human monocytes in the presence of 10−7 m Dex were negative for CD1a. Compared with control transduced DC (Ctrl‐DC), Dex‐DC expressed lower CD40, CD80 and CD86 but equivalent human leucocyte antigen‐DR. Both immature Dex‐ and Ctrl‐DC did not express CD83. Nevertheless, upon stimulation of lipopolysaccharide (LPS) or CD40 ligand, the expression of CD40, CD80, CD83 and CD86 was upregulated on Ctrl‐DC but not on Dex‐DC. The immaturity of Dex‐DC was durable following Dex removal. Interestingly, Dex‐DC maintained production of large amount of IL‐10 and little IL‐12 five days after Dex removed. Further study indicated that high‐level IL‐10 production by Dex‐DC was associated with high‐level phosphorylation of extracellular signal‐regulated kinase (ERK) as blockade of this enzyme markedly attenuated IL‐10 production. Furthermore, Dex‐DC sustained the capability of high phosphorylation of ERK and IL‐10 production 5 days after Dex removal. In addition, Dex‐DC had significantly lower activity in stimulating T‐cell proliferation. Neutralization of IL‐10, to some extent, promoted DC maturation activated by LPS, as well as T‐cell stimulatory activity of Dex‐DC. The above findings suggest that IL‐10‐producing Dex‐DC with durable immaturity are potentially useful for induction of immune tolerance.
Long‐term follow up results of intraductal papillary mucinous tumors of pancreas
Authors: LEE SUN‐YOUNG , LEE KYU TAEK , LEE JONG KYUN , JEON YONG HWAN , CHOI DONGIL , LIM JAE HOON , HEO JIN SEOK , CHOI SEONG HO , JANG KEE‐TAEK , PAIK SEUNG WOON , RHEE JONG CHUL
Published: August 2005

Background and Aim:  Intraductal papillary mucinous tumor (IPMT) of the pancreas can be divided into three clinically distinct subtypes: main duct type, branch duct type and mixed type. Although it has been reported that the branch duct type IPMT is less invasive than the main duct type IPMT, we experienced a number of branch duct type IPMT having a poor prognosis. In the present study we surveyed the survival and recurrence rates according to the subtypes.

Methods:  Sixty‐seven IPMT cases were studied to investigate clinical behavior according to the duct types. Diagnostic findings and late results of treatment were reviewed in 27 cases of the main duct type IPMT and in 35 cases of the branch duct type IPMT.

Results:  There was no statistically significant difference in the survival analysis between the main duct type IPMT and the branch duct type IPMT (P = 0.93). Seven patients (25.9%) died among the main duct type IPMT while six patients (17.1%) died among the branch duct type IPMT (P = 0.36). Tumor recurrence was noticed in four patients (18.1%) among 22 operated main duct type IPMT and in two patients (6.9%) among 29 operated branch duct type IPMT (P = 0.35).

Conclusion:  The long‐term follow up result of the branch duct type IPMT is similar to that of the main duct type IPMT. Therefore, it is not safe just to monitor the branch duct type IPMT without operation. Surgery, whenever possible, is clearly the gold standard for treatment of IPMT, regardless of duct type.
Assessing Fire Potential in a Brazilian Savanna Nature Reserve1
Authors: Mistry Jayalaxshmi , Berardi Andrea
Published: August 2005

Fire is a natural ecological force in thecerrado. However, the increasing use of fire by people means that conservation areas are subject to frequent burns. The aim of this study was to assess the potential of fire in an ecological reserve in the Brazilian savannas (cerrado) of central Brazil. Data about vegetation type, topography, climate, and fuel characteristics were input into the fire prediction models BEHAVE and FARSITE to simulate fire behavior during different weather conditions and from different entry points into the conservation area. The results indicated that there is a higher probability of fire entry from particular border regions as a result of the fuel characteristics. The presence of invasive grasses, such asMelinis minutiflora, within parts of the reserve also significantly affected the pattern of fire spread. Wind speed greatly increased the spread and extent of fire. The study showed that significant improvements in modeling fire behavior in savannas still need to be made. This study was the initial stage in the development of a decision support system for fire management in thecerrado.
Wood Decomposition of Cyrilla racemiflora (Cyrillaceae) in Puerto Rican Dry and Wet Forests: A 13‐year Case Study1
Authors: Torres Juan A. , González Grizelle
Published: August 2005

We studied the decomposition of Cyrilla racemiflora logs over a 13‐yr period in tropical dry and wet forests in Puerto Rico. The mean mass loss, ratio of soft to hard wood, nutrient concentrations, and the diversity of wood‐inhabiting organisms were greater in logs decomposing in the dry forest than in the wet forest. Termites were also more abundant in the logs collected from the tropical dry forest than the tropical wet forest. High moisture content and a low animal diversity on the logs in the wet forest seem to retard wood decay in this habitat. Wood decay rates in the tropical dry forest can be related to the high diversity of species and functional groups of wood‐inhabiting organisms.
Is hemoglobin in hemoglobin vesicles infused for isovolemic hemodilution necessary to improve oxygenation in critically ischemic hamster skin?
Authors: Plock Jan A. , Contaldo Claudio , Sakai Hiromi , Tsuchida Eishun , Leunig Michael , Banic Andrej , Menger Michael D. , Erni Dominique
Published: August 2005

The aim of this study was to test the influence of hemoglobin, encapsulated in phospholipid vesicles as an oxygen carrier, given in the course of isovolemic hemodilution to improve oxygenation in critically ischemic hamster flap tissue. Capillary hemodynamics and macromolecular leakage were investigated with intravital microscopy and analyzed off-line with the CapImage software. Partial tissue oxygen tension was measured with fluorescence quenching electrodes. The occurrence of apoptosis was assessed with the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay. Vesicles with (HbV) or without (V) encapsulated Hb were suspended in 6% hydroxyethyl starch (HES) used for the 33% blood exchange. In the ischemic tissue, hemodilution led to an increase in functional capillary density by 31% for HES ( P < 0.01 vs. other groups), 66% for V-HES, and 62% for HbV-HES (all P < 0.01 vs. control). Capillary diameters behaved inversely proportional to capillary microhemodynamics. The 20% increase in macromolecular leakage found over time in control animals was completely abolished in the vesicles groups ( P < 0.01) but not with HES. Oxygen tension was improved from 10.7 to 16.0 mmHg after HbV-HES ( P < 0.01 vs. baseline and other groups). Compared with the other groups, apoptosis was significantly reduced after HbV-HES ( P < 0.01). We conclude that the encapsulation of Hb was essential to attenuate hypoxia and subsequent cell death in the critically ischemic tissue. However, the effect was partly attributed to the rheological changes exerted by the vesicles.
Mechanisms of homocysteine-induced oxidative stress
Authors: Tyagi Neetu , Sedoris Kara C. , Steed Mesia , Ovechkin Alexander V. , Moshal Karni S. , Tyagi Suresh C.
Published: August 2005

Hyperhomocysteinemia decreases vascular reactivity and is associated with cardiovascular morbidity and mortality. However, pathogenic mechanisms that increase oxidative stress by homocysteine (Hcy) are unsubstantiated. The aim of this study was to examine the molecular mechanism by which Hcy triggers oxidative stress and reduces bioavailability of nitric oxide (NO) in cardiac microvascular endothelial cells (MVEC). MVEC were cultured for 0–24 h with 0–100 μM Hcy. Differential expression of protease-activated receptors (PARs), thioredoxin, NADPH oxidase, endothelial NO synthase, inducible NO synthase, neuronal NO synthase, and dimethylarginine-dimethylaminohydrolase (DDAH) were measured by real-time quantitative RT-PCR. Reactive oxygen species were measured by using a fluorescent probe, 2′,7′-dichlorofluorescein diacetate. Levels of asymmetric dimethylarginine (ADMA) were measured by ELISA and NO levels by the Griess method in the cultured MVEC. There were no alterations in the basal NO levels with 0–100 μM Hcy and 0–24 h of treatment. However, Hcy significantly induced inducible NO synthase and decreased endothelial NO synthase without altering neuronal NO synthase levels. There was significant accumulation of ADMA, in part because of reduced DDAH expression by Hcy in MVEC. Nitrotyrosine expression was increased significantly by Hcy. The results suggest that Hcy activates PAR-4, which induces production of reactive oxygen species by increasing NADPH oxidase and decreasing thioredoxin expression and reduces NO bioavailability in cultured MVEC by 1) increasing NO2-tyrosine formation and 2) accumulating ADMA by decreasing DDAH expression.
Measuring surface potential components necessary for transmembrane current computation using microfabricated arrays
Authors: Wiley J. James , Ideker Raymond E. , Smith William M. , Pollard Andrew E.
Published: August 2005

This study was designed to test the feasibility of using microfabricated electrodes to record surface potentials with sufficiently fine spatial resolution to measure the potential gradients necessary for improved computation of transmembrane current density. To assess that feasibility, we recorded unipolar electrograms from perfused rabbit right ventricular free wall epicardium ( n = 6) using electrode arrays that included 25-μm sensors fabricated onto a flexible substrate with 75-μm interelectrode spacing. Electrode spacing was therefore on the size scale of an individual myocyte. Signal conditioning adjacent to the sensors to control lead noise was achieved by routing traces from the electrodes to the back side of the substrate where buffer amplifiers were located. For comparison, recordings were also made using arrays built from chloridized silver wire electrodes of either 50-μm (fine wire) or 250-μm (coarse wire) diameters. Electrode separations were necessarily wider than with microfabricated arrays. Comparable signal-to-noise ratios (SNRs) of 21.2 ± 2.2, 32.5 ± 4.1, and 22.9 ± 0.7 for electrograms recorded using microfabricated sensors ( n = 78), fine wires ( n = 78), and coarse wires ( n = 78), respectively, were found. High SNRs were maintained in bipolar electrograms assembled using spatial combinations of the unipolar electrograms necessary for the potential gradient measurements and in second-difference electrograms assembled using spatial combinations of the bipolar electrograms necessary for surface Laplacian (SL) measurements. Simulations incorporating a bidomain representation of tissue structure and a two-dimensional network of guinea pig myocytes prescribed following the Luo and Rudy dynamic membrane equations were completed using 12.5-μm spatial resolution to assess contributions of electrode spacing to the potential gradient and SL measurements. In those simulations, increases in electrode separation from 12.5 to 75.0, 237.5, and 875.0 μm, which were separations comparable to the finest available with our microfabricated, fine wire, and coarse wire arrays, led to 10%, 42%, and 81% reductions in maximum potential gradients and 33%, 76%, and 96% reductions in peak-to-peak SLs. Maintenance of comparable SNRs for source electrograms was therefore important because microfabrication provides a highly attractive methods to achieve spatial resolutions necessary for improved computation of transmembrane current density.
Depressed cardiac myofilament function in human diabetes mellitus
Authors: Jweied Eias E. , McKinney Ronald D. , Walker Lori A. , Brodsky Irwin , Geha Alexander S. , Massad Malek G. , Buttrick Peter M. , de Tombe Pieter P.
Published: August 2005

Diabetes mellitus is associated with a distinct cardiomyopathy. Whether cardiac myofilament function is altered in human diabetes mellitus is unknown. Myocardial biopsies were obtained from seven diabetic patients and five control, nondiabetic patients undergoing coronary artery bypass surgery. Myofilament function was assessed by determination of the developed force-Ca2+ concentration relation in skinned cardiac cells from flash-frozen human biopsies. Separate control experiments revealed that flash freezing of biopsy specimens did not affect myofilament function. All patients in the diabetes mellitus cohort were classified as Type 2 diabetes mellitus patients, and most showed signs of diastolic dysfunction. Diabetes mellitus was associated with depressed myofilament function, that is, decreased Ca2+ sensitivity (29%, P < 0.05 vs. control) and a trend toward reduction of maximum Ca2+-saturated force (29%, P = 0.08 vs. control). The slope of the force-Ca2+ concentration relation (Hill coefficient) was not affected by diabetes, however. We conclude that human diabetes mellitus is associated with decreased cardiac myofilament function. Depressed cardiac myofilament Ca2+ responsiveness may underlie the decreased ventricular function characteristic of human diabetic cardiomyopathy.
Noninvasive three-dimensional electrocardiographic imaging of ventricular activation sequence
Authors: Zhang Xin , Ramachandra Indiresha , Liu Zhongming , Muneer Basharat , Pogwizd Steven M. , He Bin
Published: August 2005

Imaging the myocardial activation sequence is critical for improved diagnosis and treatment of life-threatening cardiac arrhythmias. It is desirable to reveal the underlying cardiac electrical activity throughout the three-dimensional (3-D) myocardium (rather than just the endocardial or epicardial surface) from noninvasive body surface potential measurements. A new 3-D electrocardiographic imaging technique (3-DEIT) based on the boundary element method (BEM) and multiobjective nonlinear optimization has been applied to reconstruct the cardiac activation sequences from body surface potential maps. Ultrafast computerized tomography scanning was performed for subsequent construction of the torso and heart models. Experimental studies were then conducted, during left and right ventricular pacing, in which noninvasive assessment of ventricular activation sequence by means of 3-DEIT was performed simultaneously with 3-D intracardiac mapping (up to 200 intramural sites) using specially designed plunge-needle electrodes in closed-chest rabbits. Estimated activation sequences from 3-DEIT were in good agreement with those constructed from simultaneously recorded intracardiac electrograms in the same animals. Averaged over 100 paced beats (from a total of 10 pacing sites), total activation times were comparable (53.3 ± 8.1 vs. 49.8 ± 5.2 ms), the localization error of site of initiation of activation was 5.73 ± 1.77 mm, and the relative error between the estimated and measured activation sequences was 0.32 ± 0.06. The present experimental results demonstrate that the 3-D paced ventricular activation sequence can be reconstructed by using noninvasive multisite body surface electrocardiographic measurements and imaging of heart-torso geometry. This new 3-D electrocardiographic imaging modality has the potential to guide catheter-based ablative interventions for the treatment of life-threatening cardiac arrhythmias.
Gene transfer of CFTR to airway epithelia: low levels of expression are sufficient to correct Cl−transport and overexpression can generate basolateral CFTR
Authors: Farmen Sara L. , Karp Philip H. , Ng Philip , Palmer Donna J. , Koehler David R. , Hu Jim , Beaudet Arthur L. , Zabner Joseph , Welsh Michael J.
Published: August 2005

Gene transfer of CFTR cDNA to airway epithelia is a promising approach to treat cystic fibrosis (CF). Most gene transfer vectors use strong viral promoters even though the endogenous CFTR promoter is very weak. To learn whether expressing CFTR at a low level in a fraction of cells would correct Cl−transport, we mixed freshly isolated wild-type and CF airway epithelial cells in varying proportions and generated differentiated epithelia. Epithelia with ∼20% wild-type cells generated ∼70% the transepithelial Cl−current of epithelia containing 100% wild-type cells. These data were nearly identical to those previously obtained with CFTR expressed under control of a strong promoter in a CF epithelial cell line. We also tested high level CFTR expression using the very strong cytomegalovirus (CMV) promoter as well as the cytokeratin-18 (K18) promoter. In differentiated airway epithelia, the CMV promoter generated 50-fold more transgene expression than the K18 promoter, but the K18 promoter generated more transepithelial Cl−current at high vector doses. Using functional studies, we found that with marked overexpression, some CFTR channels were present in the basolateral membrane where they shunted Cl−flow, thereby reducing net transepithelial Cl−transport. These results suggest that very little CFTR is required in a fraction of CF epithelial cells to complement Cl−transport because transepithelial Cl−flow is limited at the basolateral membrane. Thus they suggest a broad leeway in promoter strength for correcting the CF gene transfer, although at very high expression levels CFTR may be mislocalized to the basolateral membrane.
Macrolide antibiotics modulate ERK phosphorylation and IL-8 and GM-CSF production by human bronchial epithelial cells
Authors: Shinkai Masaharu , Foster Gregory H. , Rubin Bruce K.
Published: August 2005

Macrolide antibiotics decrease proinflammatory cytokine production in airway cells from subjects with chronic airway inflammation. However, in subjects with chronic obstructive pulmonary disease, short-term azithromycin (AZM) therapy causes a transient early increase in the blood neutrophil oxidative burst followed by a decrease in inflammatory markers with longer administration. We studied the effects of clarithromycin (CAM) and AZM on proinflammatory cytokine production from normal human bronchial epithelial (NHBE) cells. CAM decreased IL-8 over the first 6 h and then significantly increased interleukin (IL)-8 at 12–72 h after exposure ( P < 0.0001). AZM also increased IL-8 at 24 and 48 h, and CAM increased granulocyte-macrophage colony-stimulating factor at 48 h. In the presence of LPS, both CAM and AZM dose-dependently increased IL-8 secretion over 24 h, but after 5 days of exposure to 10 μg/ml CAM there is suppression of IL-8 ( P < 0.001). PD-98059, an inhibitor of MAP kinase/ERK kinase, inhibited CAM-induced IL-8 ( P < 0.0001) and GM-CSF ( P < 0.01) release. The p38 MAP kinase inhibitor SB-203580 increased CAM-induced IL-8 release ( P < 0.001), and the c-jun NH2-terminal kinase inhibitor SP-600125 had no effect on IL-8. At 120 min and 6 h, CAM increased phospho-ERK1/2 (pERK) but not phospho-p38 or phospho-JNK. Over the first 90 min, CAM at 10 μg/ml inhibited pERK and then increased pERK in parallel with measured IL-8 secretion. After daily CAM exposure for 5 days, both IL-8 and pERK returned to baseline. The p38 MAP kinase inhibitor, SB-203580 increased ERK phosphorylation and IL-8 secretion. These results suggest that macrolide antibiotics can differentially modulate proinflammatory cytokine secretion in NHBE cells, in part through ERK.
Hypoxic pulmonary hypertension: role of superoxide and NADPH oxidase (gp91phox)
Authors: Liu John Q. , Zelko Igor N. , Erbynn Efua M. , Sham James S. K. , Folz Rodney J.
Published: August 2005

Chronic exposure to low-O2tension induces pulmonary arterial hypertension (PAH), which is characterized by vascular remodeling and enhanced vasoreactivity. Recent evidence suggests that reactive oxygen species (ROS) may be involved in both processes. In this study, we critically examine the role superoxide and NADPH oxidase plays in the development of chronic hypoxic PAH. Chronic hypoxia (CH; 10% O2for 3 wk) caused a significant increase in superoxide production in intrapulmonary arteries (IPA) of wild-type (WT) mice as measured by lucigenin-enhanced chemiluminescence. The CH-induced increase in the generation of ROS was obliterated in NADPH oxidase (gp91phox) knockout (KO) mice, suggesting that NADPH oxidase was the major source of ROS. Importantly, pathological changes associated with CH-induced PAH (mean right ventricular pressure, medial wall thickening of small pulmonary arteries, and right heart hypertrophy) were completely abolished in NADPH oxidase (gp91phox) KO mice. CH potentiated vasoconstrictor responses of isolated IPAs to both 5-hydroxytryptamine (5-HT) and the thromboxane mimetic U-46619. Administration of CuZn superoxide dismutase to isolated IPA significantly reduced CH-enhanced superoxide levels and reduced the CH-enhanced vasoconstriction to 5-HT and U-46619. Additionally, CH-enhanced superoxide production and vasoconstrictor activity seen in WT IPAs were markedly reduced in IPAs isolated from NADPH oxidase (gp91phox) KO mice. These results demonstrate a pivotal role for gp91phox-dependent superoxide production in the pathogenesis of CH-induced PAH.
Oxytocin-induced labor augments IL-1β-stimulated lung fluid absorption in fetal guinea pig lungs
Authors: Nair Prem K. , Li Tianbo , Bhattacharjee Reshma , Ye Xin , Folkesson Hans G.
Published: August 2005

We tested the hypothesis that oxytocin-induced labor augmented IL-1β-induced/-stimulated lung fluid absorption in preterm guinea pig fetuses. IL-1β was administered subcutaneously daily to timed-pregnant guinea pigs for 3 days with and without simultaneous cortisol synthesis inhibition by metyrapone. At day 3, oxytocin was administered, and fetuses were delivered by abdominal hysterotomy at 61 and by oxytocin-induced birth at 68 days gestation. Delivered fetuses were instilled with isosmolar 5% albumin into the lungs, and lung fluid movement was measured over 1 h by mass balance. Lung fluid absorption was induced in 61-day and stimulated in 68-day gestation lungs by IL-1β. Labor induction by oxytocin augmented IL-1β-induced/-stimulated lung fluid absorption. Metyrapone pretreatment did not affect oxytocin-induced/-stimulated lung fluid absorption, while completely blocking IL-1β-induced/-stimulated fluid absorption. Fetal lung fluid absorption, when present, was always propranolol and amiloride sensitive, suggesting that β-adrenoceptor stimulation and amiloride-sensitive sodium channels were critical for fluid absorption. Epithelial sodium channel and Na-K-ATPase subunit expressions were both increased by IL-1β, but not further by oxytocin. Our results indicate that IL-1β release into the maternal blood circulation positively affects lung maturation due to the IL-1β-induced release of cortisol and thus prepares the lungs for the epinephrine surge associated with labor.
Divergent contractile and structural responses of the murine PKC-ε null pulmonary circulation to chronic hypoxia
Authors: Littler C. M. , Wehling C. A. , Wick M. J. , Fagan K. A. , Cool C. D. , Messing R. O. , Dempsey E. C.
Published: August 2005

Loss of PKC-ε limits the magnitude of acute hypoxic pulmonary vasoconstriction (HPV) in the mouse. Therefore, we hypothesized that loss of PKC-ε would decrease the contractile and/or structural response of the murine pulmonary circulation to chronic hypoxia (Hx). However, the pattern of lung vascular responses to chronic Hx may or may not be predicted by the acute HPV response. Adult PKC-ε wild-type (PKC-ε+/+), heterozygous null, and homozygous null (PKC-ε−/−) mice were exposed to normoxia or Hx for 5 wk. PKC-ε−/− mice actually had a greater increase in right ventricular (RV) systolic pressure, RV mass, and hematocrit in response to chronic Hx than PKC-ε+/+ mice. In contrast to the augmented PA pressure and RV hypertrophy, pulmonary vascular remodeling was increased less than expected (i.e., equal to PKC-ε+/+ mice) in both the proximal and distal PKC-ε−/− pulmonary vasculature. The contribution of increased vascular tone to this pulmonary hypertension (PHTN) was assessed by measuring the acute vasodilator response to nitric oxide (NO). Acute inhalation of NO reversed the increased PA pressure in hypoxic PKC-ε−/− mice, implying that the exaggerated PHTN may be due to a relative deficiency in nitric oxide synthase (NOS). Despite the higher PA pressure, chronic Hx stimulated less of an increase in lung endothelial (e) and inducible (i) NOS expression in PKC-ε−/− than PKC-ε+/+ mice. In contrast, expression of nNOS in PKC-ε+/+ mice decreased in response to chronic Hx, while lung levels in PKC-ε−/− mice remained unchanged. In summary, loss of PKC-ε results in increased vascular tone, but not pulmonary vascular remodeling in response to chronic Hx. Blunting of Hx-induced eNOS and iNOS expression may contribute to the increased vascular tone. PKC-ε appears to be an important signaling intermediate in the hypoxic regulation of each NOS isoform.
International equine gene mapping workshop report: a comprehensive linkage map constructed with data from new markers and by merging four mapping resources
Authors: Penedo M.C.T. , Millon L.V. , Bernoco D. , Bailey E. , Binns M. , Cholewinski G. , Ellis N. , Flynn J. , Gralak B. , Guthrie A. , Hasegawa T. , Lindgren G. , Lyons L.A. , Røed K.H. , Swinburne J.E. , Tozaki T.
Published: August 2005

A comprehensive male linkage map was generated by adding 359 new, informative microsatellites to the International Equine Gene Map half-sibling reference families and by combining genotype data from three independent mapping resources: a full sibling family created at the Animal Health Trust in Newmarket, United Kingdom, eight half-sibling families from Sweden and two half-sibling families from the University of California, Davis. Because the combined data were derived primarily from half-sibling families, only autosomal markers were analyzed. The map was constructed from a total of 766 markers distributed on the 31 equine chromosomes. It has a higher marker density than that of previously reported maps, with 626 markers linearly ordered and 140 other markers assigned to a chromosomal region. Fifty-nine markers (7%) failed to meet the criteria for statistical evidence of linkage and remain unassigned. The map spans 3,740 cM with an average distance of 6.3 cM between markers. Fifty-five percent of the intervals are ≤5 cM and only 3% ≧20 cM. The present map demonstrates the cohesiveness of the different data sets and provides a single resource for genome scan analyses and integration with the radiation hybrid map.
FISH studies on the telomeric regions of the T-cell acute lymphoblastic leukemia cell line CCRF-CEM
Authors: Wick U. , Kirsch M. , Rauch A. , Chudoba I. , Lausen B. , Efferth T. , Gebhart E.
Published: August 2005

So far, the problem of an influence of translocations on the telomeres of the involved chromosomes has not been addressed yet in human cells. Therefore, the telomeres of a karyotypically rather well characterized T-cell acute lymphoblastic leukemia (T-ALL) cell line (CCRF-CEM) with several marker chromosomes were examined using peptide nucleic acid (PNA) telomere FISH probes to compare the telomere length of these markers with that of the chromosome arms of their origin. In addition, chromosome libraries, centromeric probes, and subtelomeric DNA probes were used to further define the marker chromosomes. Two markers could be newly defined and a concise karyotype of the cell line could be obtained by these detailed examinations: 42–47,X,–X,del(5) (q35?),t(5;15)(q14;q13.2),t(8;9)(p11;p24),del(9)(:p13→qter)/inv(9)(pter→p12::q21→p12::q21→qter),+13,+20,+der(22)(p+ [HSR?])[cp]. The relative telomere length of all chromosomes showed considerable interchromosomal, intercellular, and inter-passage variation. However, it could be shown, that in four different passages of the examined cell line the observed differences between relative telomere lengths of the markers and the chromosomes of their origin, with two exceptions (short arms of del/inv9 and der22), were not significant. On the other hand, because of its mentioned variability, telomere length alone is not sufficient to reliably define the derivation of markers.
Effects of a New Isoquinolinone Derivative on Induction of Action Potential Bursts in Central Snail Neuron
Authors: Lin Chia-Hsien , Liu Ming-Chang , Lin Mei-Shan , Lin Pei-Lin , Chen Yi-Hung , Chen Chien-Tsu , Chen I-Ming , Tsai Ming-Cheng
Published: August 2005

The effects of 7-bromo-1,4-dihydro-2-phenyl-4,4-bis(4-pyridinylmethyl)2H-isoquinolin-3-one dihydrochloride (BDPBI) on induction of action potential bursts were studied pharmacologically on the RP4 central neuron of the giant African snail (Achatina fulica Ferussac). The effects of m-3M3FBS, a phospholipase activator and HTMT, a histamine (H1) receptor agonist, on the neuron were also tested. The RP4 neuron showed spontaneous firing of action potential. Extracellular application of BDPBI (150 µmol/l) reversibly elicited bursts of potential (BoP) on the neuron. m-3M3FBS and HTMT also elicited BoP on the RP4 neuron. The BoP elicited by BDPBI were blocked by U73122 (6 µmol/l), a compound commonly used as a phospholipase C (PLC) inhibitor. Neomycin (3.5 mmol/l), a high-magnesium solution (30 mmol/l), replacing the physiological sodium ion with lithium ion or adding diphenhydramine, chloropheniramine decreased the BoP elicited by BDPBI. The BoP elicited by BDPBI were not inhibited after administration with (1) prazosin, propranolol, atropine, d-tubocurarine, hexamethonium, haloperidol, cimetidine, (2) calcium-free solution, (3) high-potassium (12 mmol/l) solution, and (4) pretreatment with KT-5720. The BoP elicited by HTMT was not inhibited after administration of diphenhydramine or chloropheniramine. Voltage-clamped studies revealed that BDPBI decreased the amplitudes of calcium and steady-state outward currents while it did not alter the amplitude of the fast inward current. No negative slope relationship of the steady-state current voltage relationship was found in BDPBI-treated neurons. It is concluded that BDPBI reversibly elicited BoP in the central snail neuron. The effect was not due to (1) the extracellular calcium ion fluxes, or (2) the activation of cholinergic, adrenergic or histamine receptors. The BDPBI-elicited BoP were dependent on the phospholipase activity in the neuron.
Apolipoprotein E ε4 Allele Differentiates the Clinical Response to Donepezil in Alzheimer’s Disease
Authors: Bizzarro A. , Marra C. , Acciarri A. , Valenza A. , Tiziano F.D. , Brahe C. , Masullo C.
Published: August 2005

The existence of an association between apolipoprotein E (APOE) and Alzheimer’s disease (AD) has been reported in several studies. The possession of an ApoE ε4 allele is now considered a genetic risk factor for sporadic AD. There has been a growing agreement about the role exerted by the ApoE ε4 allele on the neuropsychological profile and the rate of cognitive decline in AD patients. However, a more controversial issue remains about a possible influence of the APOE genotype on acetylcholinesterase inhibitor therapy response in AD patients. In order to address this issue, 81 patients diagnosed as having probable AD were evaluated by a complete neuropsychological test battery at the time of diagnosis (baseline) and after 12–16 months (retest). Patients were divided into two subgroups: (1) treated with donepezil at a dose of 5 mg once a day (n = 41) and (2) untreated (n = 40). Donepezil therapy was started after baseline evaluation. The APOE genotype was determined according to standardized procedures. We evaluated the possible effect of the APOE genotype on the neuropsychological tasks in relation to donepezil therapy. The statistical analysis of the results showed a global worsening of cognitive performances for all AD patients at the retest. Differences in the clinical outcome were analysed in the four subgroups of AD patients for each neuropsychological task. ApoE ε4 carriers/treated patients had improved or unchanged scores at retest evaluation for the following tasks: visual and verbal memory, visual attention and inductive reasoning and Mini Mental State Examination. These results indicate an effect of donepezil on specific cognitive domains (attention and memory) in the ApoE ε4 carriers with AD. This might suggest an early identification of AD patients carrying at least one ε4 allele as responders to donepezil therapy.
The Changing Incentives for Security Regionalization
Authors: Press-Barnathan Galia
Published: August 2005

In this article I argue that the systemic shift to unipolarity has created an incentive to invest in security regionalization, both on the part of the American hegemon and on the part of the regional states. After defining what I mean by ‘security regionalization’, I examine the hegemonic incentives for encouraging the building of regional security institutions. Such institutions, I suggest, can advance its three main goals: to maintain regional stability, to maintain its unipolar position and to achieve system-maintenance at low cost. At the same time, regional states have increased incentives to invest in building regional security arrangements. Such arrangements, I suggest, are necessary should the hegemon choose to abandon them. They can also help prevent such abandonment by offering meaningful burden-sharing. They can serve as a ‘pact of restraint’ to restrain the hegemon, and finally they can be an avenue to a new division of labor. I apply this framework to the changes in security regionalization in Europe after the end of the Cold War (11/9 - beginning of the fall of the Berlin wall) and after the events of 9/11. I conclude by highlighting some of the tensions and paradoxes built into this security regionalization thesis.
Situational Determinants of Equitable Behavior
Authors: Thomas Kerry
Published: August 2005

Adams' dissonance-based equity theory is compared with a normative approach based on the value-expectancy-normative (VEN) model of social behaviour. This alternative view of equity phenomena avoids difficulties associated with consistency theory by attributing motivation to reduce inequity to conformity with an equity norm. It retains most of the behavioural predictions of Adams' model but emphasizes the effect of situational factors known to influence conformity. It is suggested that the VEN model is particularly useful for predicting behaviour in cases of profitable inequity where self-interest and equitable behaviour are in conflict. In the first experiment high and low profitable inequity were induced by two levels of overpayment, and reward re-allocation examined under two 'surveillance' conditions. Reward re-allocation occurred as predicted by Adams, but the effect of magnitude of inequity on outcome choice supported the VEN prediction rather than predictions derived from Adams' somewhat ambiguous statement. The effect of the surveillance variable did not reach the required level of significance. The VEN approach was further examined in the second experiment by inducing competitive and co-operative relations between P and 0 and exposing them to two levels of economic cost of conforming with the equity norm. As predicted, both the competitive relationship and high cost of conformity reduced equitable behaviour.
The Need-hierarchy and Theories of Authority
Authors: Van Fleet David D.
Published: August 2005

The need-heirarchy concept and three theories of authority (Formal, Situationist, and Acceptance) are reviewed, and an integrated framework for discussing their interrelationships and importance to organization theory and human relations is developed. The formal theory may be useful in discussions of profit-seeking, formal organizations, but in explaining individual behavior it uses only the lower order needs and expressive behavior. The situationist approach is applicable to a wider range of organizations and uses higher level needs in explaining individual behavior, but does not fully account for the impact of the individual upon his environment. The Acceptance Theory can be used in discussing any form of organization and, in addition, recognizes the full impact of the individual in those organizations using the full range of needs as well as both coping and expressive behavior. The Acceptance Theory is, then, the more general, more inclusive, and more applicable basis for a theory of authority.
Leadership Continuity in Problem-solving Groups: An Interactional Study
Authors: Cohen Arthur M. , Rosner Phillip E. , Foerst Joseph R.
Published: August 2005

This study investigated the effects of repression-sensitization communication network change, task change, and situation change on leadership continuity. Twenty-four five-man groups, homogeneously composed of either repressers or sensitizers, participated in a wheel network, a completely-connected network, and a leaderless group discussion (LGD) setting. Before the LGD setting they received either a success, failure, or no evaluation. Represser groups exhibited greater leadership continuity than sensitizer groups between the wheel and the completely-connected networks. However, through the three group settings, discontinuity tended to predominate regardless of personality or evaluation. A secondary analysis of the data investigated the reasons for these findings.
The Effect of Interpersonal Values on Laboratory Training: An Empirical Investigation
Authors: Kilmann Ralph H.
Published: August 2005

The present study investigated the effect of participant and trainer Interpersonal Value Constructs (IVC's) on the behavior and experiences that took place in eight sensitivity training groups. IVC's were defined as: mental categories through which an individual perceives and interprets the desirable and undesirable features of interpersonal behavior. The assessment of IVC's was by a scaled projective technique: the Kilmann Insight Test (KIT). Results suggest that interpersonal values as communicated by mostly nonconscious expressions do influence behavior in a T-group. In particular, depending on the match between trainer and participant IVC's (similarities and/or dissimilarities) the participant is more likely to have 'positive' interpersonal experiences in his group. Also, independent of the trainer, the specific IVC's that a participant applies in his group affects other participants becoming attracted to him and developing respect towards him.
Task Environment and Decentralization: A Cross-National Replication
Authors: Reimann Bernard C.
Published: August 2005

A study of 19 Northeast Ohio manufacturing firms replicated the major result of a recent study of 30 industrial enterprises in India, in that management concern for task environmental agents was significantly related to the organizations' degree of decentralization. However, where this relationship had been linear in the Indian context, it was curvilinear in the shape of an inverted U in the U.S. setting. For relatively centralized firms a strong positive relationship between decentralization and management concern for task agents was observed, while this relationship actually was negative for the relatively decentralized firms. Some interesting differences between the Indian and American studies were also observed for relationships between decentralization and management concern for individual task agents (such as consumers, suppliers, or employees).

In spite of some differences in the measure of both management concern and decentralization between the two studies, the replication of the Indian results in the very different industrial climate of the United States was considered as very encouraging. It suggested that management concern for task environmental agents could be a useful variable for crossnational organization research, since the relationship of this variable to decentralization was found to be similar to that observed in India, but at the same time somewhat more complex in keeping with the more complex industrial environment of the United States.
Trainer-Member Influence in T Groups: One-Way or Two-Way?
Authors: Lundgren David C.
Published: August 2005

The study examined the influence of trainer attitudes upon member attitudes toward the group, and of member attitudes upon trainer self-attitudes, at early and later time points in seven weekend T Groups. It was found that members accurately perceived trainers' attitudes toward the group and that members' own attitudes corresponded closely with their perceptions of trainer attitudes. At the early time point, self-attitudes of senior trainers showed near-significant negative correlations, and self-attitudes of co-trainers showed low positive correlations, with their perceptions of member attitudes towards themselves. At the later time point, both senior trainer and co-trainer self-attitudes were strongly associated with their perceptions of member attitudes toward themselves but these perceptions bore little relationship to actually reported member attitudes. Trainers showed a strong and consistent tendency to underestimate the favourability of member attitudes towards themselves.
A Contingency Approach to Laboratory Learning: Psychological Types Versus Experiential Norms
Authors: Kilmann Ralph H. , Taylor Vern
Published: August 2005

This study investigated the psychological dynamics and situational factors that determine whether an individual will experience support and/or confrontation in a laboratory setting. The psychological dynamics were represented by C. G. Jung's psychological types and the situational factors were the experiential norms that manifest these psychic functions. A Contingency framework was derived to suggest the conditions that will lead to the acceptance or rejection of the laboratory experience, or to self-awareness and personal growth. The research data give reasonable evidence to this framework, and the implications of the study are given for: (1) the identification of the rejectors of particular laboratory experiences, (2) the design of different laboratories via alternative experiential norms, and (3) the intervention strategies for staff and trainers according to the laboratory setting and goals.