bluuebunny/crossref_metadata_2025 huggingface dataset:
Publicly‐funded UK agricultural R&D and ‘social’ total factor productivity
Authors: Barnes Andrew P.
Published: August 2005

Most studies concerned with measuring the rate of return to publicly‐funded agricultural R&D investment have found high returns, suggesting under‐investment, and calls for increased expenditure have been common. However, the evaluation of returns tends to measure the effect of research expenditure against growth in total factor productivity (TFP), based on market inputs and outputs. When compared against growing public unease over the environmental effects of pursuing agricultural productivity growth, TFP indices become a misleading measure of growth. This paper integrates some non‐market components into the TFP index. The costs of two specific externalities of agricultural production, namely fertiliser and pesticide pollution, are integrated in a TFP index constructed for the period 1948–1995. This adjusted, or ‘social’, TFP index is measured against UK public R&D expenditures.

The rates of return to agricultural R&D are reduced by using the ‘social’ as opposed to the traditional TFP index. Whilst both remain at justifiable levels, previous studies appear to have over‐estimated the effect of agricultural R&D expenditures. Furthermore, with changes in policy towards more socially acceptable but non‐productivity enhancing outcomes, such as animal welfare, rural diversification and organic farming, the future framework for analysing returns to agricultural R&D should not be so dependent on productivity growth as an indicator of research effectiveness.
Are commodity prices chaotic?
Authors: Chatrath Arjun , Adrangi Bahram , Dhanda Kanwalroop Kathy
Published: August 2005

We conduct tests for the presence of low‐dimensional chaotic structure in the futures prices of four important agricultural commodities. Though there is strong evidence of non‐linear dependence, the evidence suggests that there is no long‐lasting chaotic structure. The dimension estimates for the commodity futures series are generally much higher than would be for low dimension chaotic series. Our test results indicate that autoregressive conditional heteroskedasticity (ARCH)‐type processes, with controls for seasonality and contract‐maturity effects, explain much of the non‐linearity in the data. We make a case that employing seasonally adjusted price series is important in obtaining robust results via some of the existing tests for chaotic structure. Finally, maximum likelihood methodologies, that are robust to the non‐linear dynamics, lend strong support to the Samuelson hypothesis of maturity effects in futures price changes.
Introduction to the special issue on spatial analysis for agricultural economists
Authors: Nelson Gerald C.
Published: August 2005

The goal of this special issue is to introduce agricultural economists to new analytical approaches involving spatial data. This paper provides a brief history of the special issue and an introduction to von Thünen's model of the determinants of land use and rent that underlies all spatial analysis.
Under the hood Issues in the specification and interpretation of spatial regression models
Authors: Anselin Luc
Published: August 2005

This paper reviews a number of conceptual issues pertaining to the implementation of an explicit “spatial” perspective in applied econometrics. It provides an overview of the motivation for including spatial effects in regression models, both from a theory‐driven as well as from a data‐driven perspective. Considerable attention is paid to the inferential framework necessary to carry out estimation and testing and the different assumptions, constraints and implications embedded in the various specifications available in the literature. The review combines insights from the traditional spatial econometrics literature as well as from geostatistics, biostatistics and medical image analysis.
Location and uptake: integrated household and GIS analysis of technology adoption and land use, with application to smallholder dairy farms in Kenya
Authors: Staal S.J. , Baltenweck I. , Waithaka M.M. , DeWolff T. , Njoroge L.
Published: August 2005

CIS‐derived measures of location and space have increasingly been used in models of land use and ecology. However, they have made few inroads into the literature on technology adoption in developing countries, which continues to rely mainly on survey‐derived information. Location, with all its dimensions of market access, demographics and agro‐climate, nevertheless remains key to understanding potential for technology use. The measures of location typically used in the adoption literature, such as locational dummy variables that proxy a range of locational factors, now appear relatively crude given the increased availability of more explicit GIs‐derived measures. This paper attempts to demonstrate the usefulness of integrating CIS‐measures into analysis of technology uptake, for better differentiating and understanding locational effects. A set of GIs‐derived measures of market access and agro‐climate are included in a standard household model of technology uptake, applied to smallholder dairy farms in Kenya, using a sample of 3330 geo‐referenced farm households. The three technologies examined are keeping of dairy cattle, planting of specialised fodder, and use of concentrate feed. Logit estimations are conducted that significantly differentiate effects of individual household characteristics from those related to location. The predicted values of the locational variables are then used to make spatial predictions of technology potential. Comparisons are made with estimations based only on survey data, which demonstrate that while overall explanatory power may not improve with CIS‐derived variables, the latter yield more practical interpretations, which is further demonstrated through predictions of technology uptake change with a shift in infrastructure policy. Although requiring large geo‐referenced data sets and high resolution GIS layers, the methodology demonstrates the potential to better unravel the multiple effects of location on farmer decisions on technology and land use.
Land use dynamics in the central highlands of Vietnam: a spatial model combining village survey data with satellite imagery interpretation
Authors: Muller Daniel , Zeller Manfred
Published: August 2005

The paper investigates geo‐physical, agro‐ecological, and socio‐economic determinants of past land use change in two districts of Dak Lak province in the Central Highlands of Vietnam and assesses the influence of rural development policies on land cover change. Landsat satellite images from the years 1975, 1992 and 2000 are interpreted to detect land cover in two time periods. A survey in randomly selected villages provides primary recall data on socio‐economic and policy variables hypothesised to influence land use change. Secondary data on rainfall, soil suitability, and topography was obtained from meteorological stations and from a digital soil map and digital elevation model. All data were spatially referenced using geographic information systems (GIS) software. A reduced‐form, multinomial logit model is used to estimate the influence of hypothesised determinants on land use and the probabilities that a certain pixel has one of five land classes during either of the two periods.

Results suggest that the first period from 1975 to 1992 was characterised by land‐intensive agricultural expansion and the conversion of forest into grass and agricultural land. During the second period, since 1992, the rapid, more labour‐ and capital‐intensive growth in the agricultural sector was enabled by the introduction of fertiliser, improved access to rural roads and markets, and expansion of the irrigated area. These policies, combined with the introduction of protected forest areas and policies discouraging shifting cultivation during the second period reduced the pressure on forests while at the same time increasing agricultural productivity and incomes for a growing population. Forest cover during the second period mainly increased due to the regeneration of areas formerly used for shifting cultivation.
Apoptosis in the epithelial cells of the rests of Malassez of the periodontium of rat molars
Authors: Cerri P. S. , Katchburian E.
Published: August 2005

Background and objectives:  Epithelial rests of Malassez are clusters of cells derived from Hertwig's root sheath that remain in the periodontal ligament throughout life. Although it is known that the cells of Malassez proliferate, there are no studies showing that they undergo programmed cell death, i.e. apoptosis. In most tissues, proliferation is balanced by apoptosis. Thus we examined regions of the periodontium of young and adult rat molars in the hope of detecting apoptosis.

Methods:  Wistar rats aged 29, 45 and 120 days were killed with chloral hydrate (600 mg/kg). Fragments containing maxillary molars were removed and fixed in formaldehyde, decalcified, and embedded in paraffin and glycol methacrylate. Sections were stained with hematoxylin/eosin and the Terminal deoxynucleotidyl transferase‐mediated dUTP Nick End Labeling (TUNEL) method for detection of apoptosis. Specimens were also fixed in glutaraldehyde‐formaldehyde, decalcified and processed for transmission electron microscopy.

Results:  Epithelial rests of Malassez containing round/ovoid basophilic dense bodies and TUNEL‐positive structures were found in all specimens examined. Ultrastructural examination revealed that some cells of Malassez contained masses of condensed peripheral chromatin and a shrunken cytoplasm exhibiting intact organelles – images typical of apoptosis. Moreover, round/ovoid electron‐opaque structures appeared to be in the process of being engulfed by neighboring epithelial cells of Malassez.

Conclusions:  Our results demonstrate that epithelial cells of Malassez's rests undergo apoptosis in the developing and adult periodontium. Apoptosis may, together with proliferation, be part of the mechanism of turnover/remodelling of the cells of Malassez.
A synergistic chlorhexidine/chitosan combination for improved antiplaque strategies
Authors: Decker E.‐M. , Von Ohle C. , Weiger R. , Wiech I. , Brecx M.
Published: August 2005

Background:  The minor efficacy of chlorhexidine (CHX) on other cariogenic bacteria than mutans streptococci such as Streptococcus sanguinis may contribute to uneffective antiplaque strategies.

Methods and Results:  In addition to CHX (0.1%) as positive control and saline as negative control, two chitosan derivatives (0.2%) and their CHX combinations were applied to planktonic and attached sanguinis streptococci for 2 min. In a preclinical biofilm model, the bacteria suspended in human sterile saliva were allowed to attach to human enamel slides for 60 min under flow conditions mimicking human salivation. The efficacy of the test agents on streptococci was screened by the following parameters: vitality status, colony‐forming units (CFU)/ml and cell density on enamel. The first combination reduced the bacterial vitality to ∼0% and yielded a strong CFU reduction of 2–3 log10 units, much stronger than CHX alone. Furthermore, the first chitosan derivative showed a significant decrease of the surface coverage with these treated streptococci after attachment to enamel.

Conclusions:  Based on these results, a new CHX formulation would be beneficial unifying the bioadhesive properties of chitosan with the antibacterial activity of CHX synergistically resulting in a superior antiplaque effect than CHX alone.
Barriers to provision of dental care in long‐term care facilities: the confrontation with ageing and death
Authors: Nitschke Ina , Ilgner Alexander , Müller Frauke
Published: August 2005

Objective:  The aim of the study was to reveal barriers to providing dental care for residents in long‐term care (LTC) facilities.

Design:  Participants were selected randomly from the dentist register in Berlin and Saxony, Germany. The sample consisted of 60 self‐employed and 60 employed dentists, a further 60 dentists worked in their own dental practice but also part‐time in an LTC facility. In semi‐structured interviews a questionnaire with 36 statements concerning working conditions, administration and cost, insecurity concerning treatment decisions as well as confrontation with ageing and death was employed. Subsequently, the study participants were asked to rank the four dimensions concerning their impact on the decision against providing dental care in an LTC facility.

Results:  The random sample was representative in age and gender for the dental register in Berlin and Saxony. Fifty‐six per cent of the participants (63% of the men and 51% of the women; 52% of the self‐employed, 60% of the employed and 56% of the consultant dentists) indicated unfavourable working conditions as biggest obstacle in providing dental care in an LTC‐facility. Thirty‐two per cent of participants rated administration and cost, 7% the insecurity in treatment decisions as major hindrance. Only 5% of the participants rated the confrontation with age and death as substantial barrier. There were no age and gender differences. Dentists in Berlin seemed more concerned about administration and cost of a consultancy activity and less secure in their therapy decisions than the colleagues from Saxony (p < 0.001). Dentists who work partly in LTC facilities were the least concerned about the confrontation with ageing and death (not significant), employed dentist showed the least secure in their treatment decisions (p > 0.001).

Conclusion:  It can be concluded that the awareness of infra‐structural and financial aspects in providing dental care in LTC facilities should be raised with health politicians and that these aspects should be considered when inaugurating or re‐structuring the consultancy services to LTC facilities. Further it would be desirable to establish more postgraduate training programmes to increase clinical and ethical competence in the area of gerodontology.
Safety of Blocking Vascular Adhesion Protein‐1 in Patients with Contact Dermatitis
Authors: Vainio Petri J. , Kortekangas‐Savolainen Outi , Mikkola Jari H. , Jaakkola Kimmo , Kalimo Kirsti , Jalkanen Sirpa , Veromaa Timo
Published: August 2005

Abstract: Vascular adhesion protein‐1 mediates leukocyte binding to vascular endothelia and migration to tissues. It is upregulated in inflammatory conditions. We studied the safety of vascular adhesion protein‐1 blockade by a single dose of the mouse monoclonal antibody vepalimomab in patients with nickel‐induced allergic contact dermatitis lesions. Vepalimomab, 0.05–0.50 mg kg−1 was safe and well tolerated. Four of nine patients reported adverse events of mild to moderate intensity. Human antimouse antibodies were detected after infusion in all the patients and they remained above the basal level for at least one month. Vepalimomab dose‐dependently labelled vascular adhesion protein‐1 in the inflamed skin. Luminal upregulation of vascular adhesion protein‐1 on the endothelium upon inflammation was demonstrated for the first time in patients in vivo. Vepalimomab was found on the endothelium up to 24 hr after dosing whilst it was cleared from the circulation with an apparent half‐life of 25–50 min. The results provide in vivo support for the concept of blocking vascular adhesion protein‐1 in human disease states and support previous proposals that vascular adhesion protein‐1 is a potential target molecule for inhibition of inflammatory reactions.
Dose‐Dependent Liver Tissue Repair After Chloroform plus Trichloroethylene Binary Mixture
Authors: Anand Sathanandam S. , Mumtaz Moiz M. , Mehendale Harihara M.
Published: August 2005

Abstract: The aim of the present study was to investigate the hypothesis that liver tissue repair induced by exposure to chloroform (CHCl3)+trichloroethylene binary mixture (BM) is dose‐dependent similar to that elicited by exposure to these compounds individually. Male Sprague‐Dawley rats (250–300 g) received three dose combinations of binary mixture (74+250, 185+500 and 370+1250 mg CHCl3+trichloroethylene/kg, intraperitoneally) in corn oil (maximum of 0.5 ml/kg). Liver injury was assessed by plasma alanine amino transaminase (ALT) activity and histopathology by haematoxylin & eosin. Liver tissue repair was measured by 3H‐thymidine incorporation into hepatonuclear DNA. Blood and liver levels of both the parent compounds and two major metabolites of trichloroethylene (trichloroacetic acid and trichloroethanol) were quantified by gas chromatography. The blood and liver CHCl3 levels after the administration of binary mixture were similar compared to the administration of CHCl3 alone. The blood and liver trichloroethylene levels after the binary mixture were significantly lower compared to trichloroethylene alone due to higher elimination in presence of CHCl3, resulting in decreased production of metabolites. The antagonistic toxicokinetics resulted in lower liver injury than the summation of injury caused by the individual components at all three dose levels. On the other hand, tissue repair elicited by the binary mixture was dose‐dependent. The interactive toxicity of this binary mixture of CHCl3 and trichloroethylene led to subadditive initial liver injury because of a combined effect of higher elimination of TCE and mitigated progression of liver injury was prevented by timely dose‐dependent stimulation of compensatory tissue repair. Even though the doses of the toxicants employed in this study are much higher than found in the environment, the results suggest that a mixture of these two compounds at environmental levels is unlikely to cause any exaggerated interactive acute liver toxicity of any biological significance.
Attenuation of Stress‐Elicited Brain Catecholamines, Serotonin and Plasma Corticosterone Levels by Calcined Gold Preparations Used in Indian System of Medicine
Authors: Shah Zahoor Ahmad , Gilani Rabia Afzal , Sharma Pragya , Vohora Shashi Bharat
Published: August 2005

Abstract: Problems associated with mental health have increased tremendously in modern times. The search for effective and safe alternatives should, therefore, be persued vigourously. Forced immobilization is one of the best explored models of stress in rats and the role of corticosterone, serotonin (5‐HT) and catecholamines, i.e. norepinephrine, epinephrine, dopamine is well documented. We investigated the therapeutic potential of two gold preparations (Ayurvedic Swarna Bhasma and Unani Kushta Tila Kalan) in restraint induced stress at different time points of 1 hr, 2 hr and 4 hr. We pretreated rats with two gold prepaprations, Ayurvedic Swarna Bhasma and Unani Kushta Tila Kalan (25 mg/kg, orally for 10 days) prior to restraint stress. Brain catecholamine, serotonin and plasma corticosterone levels were determined following 1, 2 and 4 hr restraint stress, using HPLC and also plasma corticosterone using luminescence spectrophotometry. Gold preparations restored restraint stress‐induced elevation in levels of brain catecholamines (norepinephrine, epinephrine and dopmine), 5‐HT and plasma corticosterone to near normal levels. Gold, widely used in modern medicine for the treatment of rheumatoid arthritis, is highly valued for various medicinal uses in Indian systems of medicine. Traditional gold preparations are attributed with tonic/rejuvenating and antioxidant properties. Our earlier studies revealed interesting analgesic, immunostimulant, adaptogenic and glycogen sparing properties in these preparations, but their effects in stress and depression have not been investigated yet. Significant restoration of altered values to near normal levels suggest potentials for gold preparations in stress and depression.
Aloe Emodin‐Induced Apoptosis in t‐HSC/Cl‐6 Cells Involves a Mitochondria‐Mediated Pathway
Authors: Lian Li‐Hua , Park Eun‐Jeon , Piao Hui‐Shan , Zhao Yu‐Zhe , Sohn Dong Hwan
Published: August 2005

Abstract: The aim of our study was to clarify the apoptosis pathway induced by aloe emodin, an hydroxyanthraquinone present in aloe vera leaves, in rat hepatic stellate cells transformed by simian virus 40 (t‐HSC/Cl‐6), which retain the features of activated rat stellate cells. Apoptosis was determined by DNA fragmentation, caspase activity assay and western blotting analysis. Treatment of t‐HSC/Cl‐6 cells with 12.5, 25, or 50 μM aloe emodin inhibited t‐HSC/Cl‐6 cell viability in a dose‐ and time‐dependent manner. The induction of apoptosis by aloe emodin was confirmed by typical DNA ladder formation and annexin v‐propidium iodide flow‐cytometric analysis. Aloe emodin treatment of t‐HSC/Cl‐6 cells caused activation of caspase‐3 and caspase‐9, detected with a caspase activity assay, although no change was observed in caspase‐8 activity. Western blotting showed caspase‐3 and caspase‐9 active forms and the subsequent proteolytic cleavage of poly(ADP‐ribose) polymerase. Aloe emodin induced mitochondrial membrane depolarization. Our data also show that cytochrome c increased in the cytosol but decreased in the mitochondria in a time‐dependent manner. Increased Bax and unchanged Bcl‐2 levels resulted in an increased Bax/Bcl‐2 ratio. Thus, our research provides evidence that aloe emodin‐induced apoptosis involves a mitochondria‐associated apoptosis pathway.
Antidepressants in the Treatment of Neuropathic Pain
Authors: Sindrup Søren H. , Otto Marit , Finnerup Nanna B. , Jensen Troels S.
Published: August 2005

Abstract: Neuropathic pain is due to lesion or dysfunction of the peripheral or central nervous system. Tricyclic antidepressants and anticonvulsants have long been the mainstay of treatment of this type of pain. Tricyclic antidepressants may relieve neuropathic pain by their unique ability to inhibit presynaptic reuptake of the biogenic amines serotonin and noradrenaline, but other mechanisms such as N‐methyl‐D‐aspartate receptor and ion channel blockade probably also play a role in their pain‐relieving effect. The effect of tricyclic antidepressants in neuropathic pain in man has been demonstrated in numerous randomised, controlled trials, and a few trials have shown that serotonin noradrenaline and selective serotonin reuptake inhibitor antidepressants also relieve neuropathic pain although with lower efficacy. Tricyclic antidepressants will relieve one in every 2–3 patients with peripheral neuropathic pain, serotonin noradrenaline reuptake inhibitors one in every 4–5 and selective serotonin reuptake inhibitors one in every 7 patients. Thus, based on efficacy measures such as numbers needed to treat, tricyclic antidepressants tend to work better than the anticonvulsant gabapentin and treatment options such as tramadol and oxycodone, whereas the serotonin noradrenaline reuptake inhibitor venlafaxine appears to be equally effective with these drugs and selective serotonin reuptake inhibitors apparently have lower efficacy. Head‐to‐head comparisons between antidepressants and the other analgesics are lacking. Contraindications towards the use of tricyclic antidepressants and low tolerability in general of this drug class – may among the antidepressants – favour the use of the serotonin noradrenaline reuptake inhibitors. A recent study on bupropion, which is a noradrenaline and dopamine uptake inhibitor, indicated a surprisingly high efficacy of this drug in peripheral neuropathic pain. In conclusion, antidepressants represent useful tools in neuropathic pain treatment and must still be considered as first line treatments of neuropathic pain. However, without head‐to‐head comparisons between antidepressants and other analgesics, it is not possible to provide real evidence‐based treatment algorithms for neuropathic pain.
The effects of the insulin-like growth factor-I aptamer, NBI-31772, on glucose homeostasis in the mouse
Authors: Silha Josef V , Murphy Liam J
Published: August 2005

The majority of insulin-like growth factor-I (IGF-I) in the adult rodent circulation is bound to high affinity IGF binding proteins. We investigated the changes in IGF-I clearance, blood glucose and plasma insulin levels, and tissue 2-deoxyglucose uptake after intravenous administration of the IGF aptamer, NBI-31772, which selectively competes with IGF-I for binding to the IGFBPs, but has no effect at the IGF-I receptor. Clearance of 125I-IGF-I was significantly increased in NBI-31772-treated mice compared with vehicle-treated mice (t1/2 = 45.0 ± 1.9 vs. 56.3 ± 3.9 min, respectively; p = 0.021). However, NBI-31772 had no significant effect on glucose levels, and no insulin sparing effect was apparent neither under basal conditions nor during an intravenous glucose challenge. The decline in the specific activity after 3H-2-deoxyglucose administration was significantly less rapid in NBI-31772-treated mice compared with controls, suggesting that the IGF-I aptamer had an inhibitory effect on hepatic gluconeogenesis. In contrast, no insulin-like effect was apparent in other tissues examined. 3H-2-deoxyglucose accumulation was similar in all tissues analyzed, including skeletal muscle, which is thought to be particularly sensitive to IGF-I. These data suggest that the IGF-I aptamer affects clearance of radiolabeled IGF-I from the circulation, but has no marked effects on glucose nor insulin homeostasis. The search for hydrophilic IGF aptamers with longer duration of action that could be used in the treatment of diabetes may be rewarding. Key words: insulin resistance, gluconeogenesis, 2-deoxyglucose uptake, glucose clearance.
ON TIME-SPACE NONCOMMUTATIVITY FOR TRANSITION PROCESSES AND NONCOMMUTATIVE SYMMETRIES
Authors: BALACHANDRAN A. P. , PINZUL ALEKSANDR
Published: August 2005

We explore the consequences of time-space noncommutativity in the quantum mechanics of atoms and molecules, focusing on the Moyal plane with just time-space noncommutativity [Formula: see text]. Space rotations and parity are not automorphisms of this algebra and are not symmetries of quantum physics. Still, when there are spectral degeneracies of a time-independent Hamiltonian on a commutative spacetime which are due to symmetries, they persist when θ0i≠0: they do not depend at all on θ0i. They give no clue about rotation and parity violation when θ0i≠0. The persistence of degeneracies for θ0i≠0 can be understood in terms of invariance under deformed noncommutative "rotations" and "parity". They are not spatial rotations and reflection. We explain such deformed symmetries. We emphasize the significance of time-dependent perturbations (for example, due to time-dependent electromagnetic fields) to observe noncommutativity. The formalism for treating transition processes is illustrated by the example of nonrelativistic hydrogen atom interacting with quantized electromagnetic field. In the tree approximation, the 2s→1s + γ transition for hydrogen is zero in the commutative case. As an example, we show that it is zero in the same approximation for θ0i≠0. The importance of the deformed rotational symmetry is commented upon further using the decay Z0→2γ as an example.
HYBRID ANALYTIC-NUMERIC METHOD FOR LIGHT THROUGH A BOUNDED PLANAR DIELECTRIC STRUCTURE
Authors: NICOLAU J. B. , VAN GROESEN E.
Published: August 2005

We present a hybrid analytic-numeric method to calculate the transmission and reflection of light that is fluxed into a bounded complicated optical structure surrounded by air. The solution is obtained by numerical calculations inside a square containing the structure and by analytical calculations outside the square. For solving the 2D Helmholtz equation we formulate transparent-influx boundary conditions (TIBCs) on the boundaries of the square; these are incorporated into a variational formulation of the Helmholtz equation to obtain a FEM-implementation for the interior calculations.
ENVIRONMENTAL JUSTICE: Human Health and Environmental Inequalities
Authors: Brulle Robert J. , Pellow David N.
Published: August 2005

▪ Abstract  In this review, we provide an introduction to the topics of environmental justice and environmental inequality. We provide an overview of the dimensions of unequal exposures to environmental pollution (environmental inequality), followed by a discussion of the theoretical literature that seeks to explain the origins of this phenomenon. We also consider the impact of the environmental justice movement in the United States and the role that federal and state governments have developed to address environmental inequalities. We conclude that more research is needed that links environmental inequalities with public health outcomes.
Aldosterone Stimulates Vascular Smooth Muscle Cell Proliferation Via Big Mitogen-Activated Protein Kinase 1 Activation
Authors: Ishizawa Keisuke , Izawa Yuki , Ito Hiroyuki , Miki Chieko , Miyata Kayoko , Fujita Yoshiko , Kanematsu Yasuhisa , Tsuchiya Koichiro , Tamaki Toshiaki , Nishiyama Akira , Yoshizumi Masanori
Published: August 2005

The nongenomic effects of aldosterone have been implicated in the pathogenesis of various cardiovascular diseases. Aldosterone-induced nongenomic effects are attributable in part to the activation of extracellular signal-regulated kinase 1/2 (ERK1/2), a classical mitogen-activated protein (MAP) kinase. Big MAP kinase 1 (BMK1), a newly identified MAP kinase, has been shown to be involved in cell proliferation, differentiation, and survival. We examined whether aldosterone stimulates BMK1-mediated proliferation of cultured rat aortic smooth muscle cells (RASMCs). Mineralocorticoid receptor (MR) expression and localization were evaluated by Western blotting analysis and fluorolabeling methods. ERK1/2 and BMK1 activities were measured by Western blotting analysis with the respective phosphospecific antibodies. Cell proliferation was determined by Alamar Blue colorimetric assay. Aldosterone (0.1 to 100 nmol/L) dose-dependently activated BMK1 in RASMCs, with a peak at 30 minutes. To clarify whether aldosterone-induced BMK1 activation is an MR-mediated phenomenon, we examined the effect of eplerenone, a selective MR antagonist, on aldosterone-induced BMK1 activation. Eplerenone (0.1 to 10 μmol/L) dose-dependently inhibited aldosterone-induced BMK1 activation in RASMCs. Aldosterone also stimulated RASMC proliferation, which was inhibited by eplerenone. Aldosterone-mediated phenomena were concluded to be attributable to a nongenomic effect because cycloheximide failed to inhibit aldosterone-induced BMK1 activation. Transfection of dominant-negative MAP kinase/ERK kinase 5 (MEK5), which is an upstream regulator of BMK1, partially inhibited aldosterone-induced RASMC proliferation, which was almost completely inhibited by MEK inhibitor PD98059. In addition to the classical steroid activity, rapid nongenomic effects induced by aldosterone may represent an alternative etiology for vascular diseases such as hypertension.
Regulation of Discoidin Domain Receptor 2 by Cyclic Mechanical Stretch in Cultured Rat Vascular Smooth Muscle Cells
Authors: Shyu Kou-Gi , Chao Ya-Meng , Wang Bao-Wei , Kuan Peiliang
Published: August 2005

Discoidin domain receptor 2 (DDR2) plays potential roles in the regulation of collagen turnover mediated by smooth muscle cells in atherosclerosis. How mechanical stretch affects the regulation of DDR2 in smooth muscle cells is not fully understood. We sought to investigate the cellular and molecular mechanisms of regulation of DDR2 by cyclic stretch in smooth muscle cells. Rat vascular smooth muscle cells grown on a flexible membrane base were stretched by vacuum to 20% of maximum elongation, at 60 cycles/min. Cyclic stretch significantly increased DDR2 protein and mRNA expression after stretch. Cyclic stretch also significantly increased DNA–protein binding activity of Myc-Max. Addition of SB203580, transforming growth factor-β1 (TGF-β1) monoclonal antibody, p38 small interfering RNA (siRNA), and c-myc siRNA 30 minutes before stretch inhibited the induction of DDR2 protein and abolished the DNA–protein binding activity induced by cyclic stretch. Cyclic stretch increased, whereas SB203580 abolished the phosphorylated p38 protein. Conditioned medium from stretched smooth muscle cells and exogenous administration of angiotensin II and TGF-β1 recombinant proteins to the nonstretched cells increased DDR2 protein expression similar to that seen after stretch. In conclusion, cyclic mechanical stretch enhances DDR2 expression in cultured rat smooth muscle cells. The stretch-induced DDR2 is mediated by angiotensin II and TGF-β1, at least in part, through p38 mitogen-activated protein kinase and Myc pathway.
Discrepancies Between Catheter Tip and Tissue Temperature in Cooled-Tip Ablation
Authors: Bruce G. Keith , Bunch T. Jared , Milton Mark A. , Sarabanda Alvaro , Johnson Susan B. , Packer Douglas L.
Published: August 2005

Background—

It is not known whether catheter tip temperatures with a cooled-tip ablation can be reliably extrapolated to estimate actual tissue temperatures. The relationship between catheter tip temperatures, tissue temperatures, power, and microbubble formation is not known.

Methods and Results—

Nine dogs underwent 111 radiofrequency energy deliveries at the pulmonary vein ostia with a cooled-tip catheter. Catheter tip and tissue temperatures were markedly discrepant. Catheter tip temperature plateaus at 36°C to 39°C with increasing power, whereas tissue temperature increases to a mean of 75±3°C at 45 W (maximum temperature >100°C). Seventy-two energy deliveries were performed, titrating power to microbubble formation guided by intracardiac echocardiography. Type I and II microbubble formation occurred in 45 (63%) and 19 (26%) ablations, respectively. Type I microbubble emergence occurred at lower powers (21±8 versus 26±4 W;
P
=0.05), catheter tip temperatures (38±5°C versus 48±10°C;
P
=0.02), and tissue temperatures (65±19°C versus 81±9°C;
P
<0.001) than type II microbubble formation. Maximum impedance decreases during ablation before microbubble formation were less with type I microbubble (20±9 versus 37±11 Ω;
P
<0.001) compared with type II microbubbles. One quarter of type I microbubbles abruptly transitioned to type II microbubbles with significant changes in power or catheter tip temperature. No microbubbles were seen in 19 ablations (26%) despite powers up to 26±9 W and tissue temperatures up to 81±17°C.

Conclusions—

Catheter tip and tissue temperatures are markedly discrepant during cooled-tip ablation. Type I and II microbubble formation occurs at overlapping power and catheter tip and tissue temperature ranges. Neither the absence of microbubbles nor the presence of type I microbubble formation ensures against excessive tissue heating. The appearance of microbubbles may indicate possible tissue overheating and signal a need to decrease energy.
Left Ventricular Concentric Remodeling Is Associated With Decreased Global and Regional Systolic Function
Authors: Rosen Boaz D. , Edvardsen Thor , Lai Shenghan , Castillo Ernesto , Pan Li , Jerosch-Herold Michael , Sinha Shantanu , Kronmal Richard , Arnett Donna , Crouse John R. , Heckbert Susan R. , Bluemke David A. , Lima Joao A.C.
Published: August 2005

Background—

The transition from compensatory concentric remodeling to myocardial failure is not completely understood in humans. To investigate determinants of incipient myocardial dysfunction, we examined the association between concentric remodeling and regional LV function in asymptomatic participants of the Multi-Ethnic Study of Atherosclerosis (MESA).

Methods and Results—

Myocardial tagged MRI was performed. Regional myocardial function expressed as peak systolic midwall circumferential strain (Ecc) was analyzed in 441 consecutive studies by HARP (Harmonic Phase) tool. Peak Ecc was correlated with the extent of concentric remodeling determined by the ratio of left ventricular mass to end-diastolic volume (M/V ratio). In men, a gradual decline in peak global Ecc was seen with increasing M/V ratio (test for trend,
P
<0.001). Among women, however, Ecc tended to be lower only in the fifth compared with the first quintile of M/V ratio (
P
=0.1). The association of lower Ecc with increasing M/V ratio was regionally heterogeneous but was particularly prominent in the LAD region in men (test for trend,
P
<0.001) and in women (test for trend,
P
=0.02). In the right coronary and left circumflex artery territories, these associations were less marked in both genders.

Conclusions—

In this cross-sectional study of asymptomatic individuals, concentric left ventricular remodeling was related to decreased regional systolic function. The reduction in regional function, which was more pronounced in the left anterior descending coronary artery territory, may reflect the local transition from compensatory remodeling to myocardial dysfunction.
Bilirubin
Authors: Öllinger Robert , Bilban Martin , Erat Anna , Froio Alberto , McDaid James , Tyagi Shivraj , Csizmadia Eva , Graça-Souza Aurelio V. , Liloia Angela , Soares Miguel P. , Otterbein Leo E. , Usheva Anny , Yamashita Kenichiro , Bach Fritz H.
Published: August 2005

Background—

Bilirubin, a natural product of heme catabolism by heme oxygenases, was considered a toxic waste product until 1987, when its antioxidant potential was recognized. On the basis of observations that oxidative stress is a potent trigger in vascular proliferative responses, that heme oxygenase-1 is antiatherogenic, and that several studies now show that individuals with high-normal or supranormal levels of plasma bilirubin have a lesser incidence of atherosclerosis-related diseases, we hypothesized that bilirubin would have salutary effects on preventing intimal hyperplasia after balloon injury.

Methods and Results—

We found less balloon injury–induced neointima formation in hyperbilirubinemic Gunn rats and in wild-type rats treated with biliverdin, the precursor of bilirubin, than in controls. In vitro, bilirubin and biliverdin inhibited serum-driven smooth muscle cell cycle progression at the G
1
phase via inhibition of the mitogen-activated protein kinase signal transduction pathways and inhibition of phosphorylation of the retinoblastoma tumor suppressor protein.

Conclusions—

Bilirubin and biliverdin might be potential therapeutics in vascular proliferative disorders.
Intrinsic Histological Abnormalities of Aortic Root and Ascending Aorta in Tetralogy of Fallot
Authors: Tan J.L. , Davlouros P.A. , McCarthy K.P. , Gatzoulis M.A. , Ho S.Y.
Published: August 2005

Background—

Dilatation of the aortic root is a known feature in tetralogy of Fallot (TOF) patients with pulmonary stenosis (PS) or pulmonary atresia (PA). We hypothesized that intrinsic histological abnormalities of the aortic wall present since infancy are an important causative factor leading to aortic root dilatation.

Methods and Results—

We examined the aortic histology of 17 cases with TOF and PS/PA from our cardiac morphology archive and compared them with a control group of normal aortas. Measured circumference of the aortic root at the sinotubular junction and at the ascending aorta was indexed to the left ventricle. Aortic walls were studied by light microscopy with the use of various stains. Seventeen TOF cases (7 with PS, 10 with PA) including 7 infants, 2 children, and 8 adults were compared with 11 hearts with normal aorta. Aortic root circumference to left ventricular index and ascending aortic circumference to left ventricular index were 1.24±0.25 and 1.37±0.24, respectively, in the TOF group versus 0.89±0.10 and 0.88±0.11, respectively, in the control group (
P
<0.001). Histological changes of grade 2 or 3 were present in 29% (medionecrosis), 82% (fibrosis), 35% (cystic medial necrosis), and 59% (elastic fragmentation) in the ascending aorta of the TOF group. Histology grading scores were significantly higher in the TOF group (median score, 7; range, 1 to 12) compared with normal controls (median score, 2; range, 0 to 6) and correlated with the ascending aortic circumference to left ventricular index (
r
=0.525,
P
=0.03).

Conclusions—

There are marked histological abnormalities in the aortic root and ascending aortic wall of patients with TOF present from infancy, suggesting a causative mechanism for subsequent aortic root dilatation.
Low-Grade Albuminuria and Incidence of Cardiovascular Disease Events in Nonhypertensive and Nondiabetic Individuals
Authors: Ärnlöv Johan , Evans Jane C. , Meigs James B. , Wang Thomas J. , Fox Caroline S. , Levy Daniel , Benjamin Emelia J. , D’Agostino Ralph B. , Vasan Ramachandran S.
Published: August 2005

Background—

Data are limited with regard to the relations of low-grade albuminuria (below the microalbuminuria threshold) and incidence of cardiovascular disease (CVD) events in nondiabetic, nonhypertensive individuals.

Methods and Results—

We examined the association of urinary albumin excretion (spot urine albumin indexed to creatinine [UACR]) and the incidence of CVD events and all-cause mortality in 1568 nonhypertensive, nondiabetic Framingham Offspring Study participants (mean age, 55 years; 58% women) free of CVD. On follow-up (median, 6 years), 54 participants (20 women) developed a first CVD event, and 49 (19 women) died. After adjustment for established risk factors, increasing UACR was associated with greater risk of CVD (hazards ratio [HR] per SD increment in log UACR, 1.36; 95% CI, 1.00 to 1.87) and death (HR per SD increment in log UACR, 1.55; 95% CI, 1.10 to 2.20). Participants with UACR greater than or equal to the sex-specific median (≥3.9 μg/mg for men, ≥7.5 μg/mg for women) experienced a nearly 3-fold risk of CVD (adjusted HR, 2.92; 95% CI, 1.57 to 5.44;
P
<0.001) and a borderline significantly increased risk of death (adjusted HR, 1.75; 95% CI, 0.95 to 3.22;
P
=0.08) compared with those with UACR below the median. The increased CVD risk associated with UACR at or above the median remained robust in analyses restricted to individuals without microalbuminuria (n=1470) and in subgroups with intermediate (n=1469) and low (n=1186) pretest probabilities of CVD.

Conclusions—

In our community-based sample of middle-aged nonhypertensive, nondiabetic individuals, low levels of urinary albumin excretion well below the current microalbuminuria threshold predicted the development of CVD. Our observations add to the growing body of evidence that challenges the notion that UACR <30 μg/mg indicates “normal” albumin excretion.
On the Shape–Slope Relation of Drop Size Distributions in Convective Rain
Authors: Seifert Axel
Published: August 2005

The relation between the slope and shape parameters of the raindrop size distribution parameterized by a gamma distribution is examined. The comparison of results of a simple rain shaft model with an empirical relation based on disdrometer measurements at the surface shows very good agreement, but a more detailed discussion reveals some difficulties—for example, deviations from the gamma shape and the overestimation of collisional breakup.
Hydrometeor Retrieval Accuracy Using Microwave Window and Sounding Channel Observations
Authors: Bauer Peter , Moreau Emmanuel , Di Michele Sabatino
Published: August 2005

The retrieval errors of cloud and precipitation hydrometeor contents from spaceborne observations are estimated at microwave frequencies in atmospheric windows between 18 and 150 GHz and in oxygen absorption complexes near 50–60 and 118 GHz. The method is based on a variational retrieval framework using a priori information on the cloud, atmosphere, and surface states from ECMWF short-range forecasts under different weather regimes. This approach was chosen because a consistent description of the model state and its uncertainties is provided, which is unavailable for other methods. The results show that the sounding channels provide more stable, more accurate, and less biased retrievals than window channels—in particular, over land surfaces and with regard to snowfall. Average performance estimates showed that if sounding channels are used, 80% of all retrievals are within 100% error limits and 60% of them are within 50% error limits with regard to rainfall. For snowfall, the sounding channels produce 60% of all retrievals with errors below 100% for rates smaller than 1 mm h−1, and 50%–80% of the cases have errors below 50% for more intense snowfall.
Application of a Multigrid Method to a Mass-Consistent Diagnostic Wind Model
Authors: Wang Yansen , Williamson Chatt , Garvey Dennis , Chang Sam , Cogan James
Published: August 2005

A multigrid numerical method has been applied to a three-dimensional, high-resolution diagnostic model for flow over complex terrain using a mass-consistent approach. The theoretical background for the model is based on a variational analysis using mass conservation as a constraint. The model was designed for diagnostic wind simulation at the microscale in complex terrain and in urban areas. The numerical implementation takes advantage of a multigrid method that greatly improves the computation speed. Three preliminary test cases for the model’s numerical efficiency and its accuracy are given. The model results are compared with an analytical solution for flow over a hemisphere. Flow over a bell-shaped hill is computed to demonstrate that the numerical method is applicable in the case of parameterized lee vortices. A simulation of the mean wind field in an urban domain has also been carried out and compared with observational data. The comparison indicated that the multigrid method takes only 3%–5% of the time that is required by the traditional Gauss–Seidel method.
Sinlessness and Uncertainty in Jesus
Authors: Neville Graham
Published: August 2005

There are over seventy separate occasions on which Jesus is portrayed in the Gospels as asking questions. A substantial number of these are open questions; and some of them seem to imply that Jesus was himself uncertain about an answer. Can this analysis be reconciled with the orthodox Christian doctrine of his sinlessness?
The Damned Rich (Mark 10:17-31)
Authors: Crossley James G.
Published: August 2005

On the level of the historical Jesus the condemnation of the rich found in Mark 10:17-31 ought to be read in the strongest possible sense: they will be damned if they do not give up their wealth. This is supported by Jewish theological traditions and the socio-economic context of the 20s Galilee.
Neoliberalism and Empire: How Are They Related?
Authors: Prasch Robert E.
Published: August 2005

It is argued that when the world’s economic and military hegemon pursues a foreign economic policy of liberalism, there are tendencies for that nation to acquire an empire. These arguments are illustrated with examples from the British Empire of the nineteenth century. The article concludes with some speculations on the current situation, with the United States now in the role of the world’s hegemon.
Capital Accumulation and the Development of a Financial System: The Turkish Example
Authors: Eres Benan
Published: August 2005

This article aims at constructing an alternative view of the development of a financial system in Turkey. The main argument is that the historically specific form of accumulation is the fundamental reason why national financial systems developed as they did. The predominantly commercial form of accumulation as well as the peripheral conditions shape the development of the financial system in Turkey. Furthermore, the rise of “holding” banking in the 1970s is argued to be the culmination of these specific factors.
Cuban Economic Performance in Retrospect
Authors: Thompson Frank W.
Published: August 2005

The performance of the Cuban economy during the past half century is evaluated. The primary focus is on per capita GDP, but consideration is given as well to the Human Development Index (HDI) and even broader conceptions of human development. The summary conclusion is that Cuba has performed well neither absolutely nor in comparison with the rest of Latin America and that the main causes for this must be domestic.