bluuebunny/crossref_metadata_2025_split huggingface dataset:
Elevated levels of C‐reactive protein are associated with impaired coronary collateral development
Authors: Gulec S. , Ozdemir A. O. , Maradit‐Kremers H. , Dincer I. , Atmaca Y. , Erol C. 
Published: May 2006

AbstractBackground  In vitro studies have shown that C‐reactive protein (CRP) attenuates nitric oxide production and inhibits angiogenesis, which may result in impaired collateral development. The aim of this study was to investigate the association between high sensitivity CRP (hsCRP) levels and the extent of coronary collaterals.Materials and methods  We investigated the association between hsCRP levels and the extent of coronary collaterals according to the Rentrop classification in a cohort of 185 patients who had high‐grade coronary stenosis or occlusion on their angiograms.Results  Mean age was 62 years and 80% were males. Subjects with a higher grade of collaterals were significantly less likely to have diabetes mellitus (OR; 0·48, 95% and CI; 0·28, 0·83) or acute coronary syndrome (OR; 0·58, 95% and CI; 0·33, 0·99), but they were more likely to have higher number of vessels with significant stenosis (OR; 1·41, 95% and CI; 1·03, 1·93) and to have received statins (OR; 1·84, 1.09, 3.13). The mean hsCRP values reduced significantly as the Rentrop grades increased (trend, P = 0·0006). After adjusting for age, gender, statin use, clinical presentation with acute coronary syndrome, diabetes mellitus and the number of vessels with significant stenosis, each 10‐unit increase in hsCRP values corresponded to a 31% reduced odds of having a higher collateral score (OR; 0·69, 95% and CI; 0·53, 0·90).Conclusions  Our findings indicate that elevated hsCRP levels are associated with a significant impairment in coronary collateralization. These data suggest a previously unrecognized mechanism through which inflammation may worsen cardiovascular outcomes.
Stabilization of organic matter in temperate soils: mechanisms and their relevance under different soil conditions – a review
Authors: Lützow M. v. , Kögel‐Knabner I. , Ekschmitt K. , Matzner E. , Guggenberger G. , Marschner B. , Flessa H. 
Published: May 2006

SummaryMechanisms for C stabilization in soils have received much interest recently due to their relevance in the global C cycle. Here we review the mechanisms that are currently, but often contradictorily or inconsistently, considered to contribute to organic matter (OM) protection against decomposition in temperate soils: (i) selective preservation due to recalcitrance of OM, including plant litter, rhizodeposits, microbial products, humic polymers, and charred OM; (ii) spatial inaccessibility of OM against decomposer organisms due to occlusion, intercalation, hydrophobicity and encapsulation; and (iii) stabilization by interaction with mineral surfaces (Fe‐, Al‐, Mn‐oxides, phyllosilicates) and metal ions. Our goal is to assess the relevance of these mechanisms to the formation of soil OM during different stages of decomposition and under different soil conditions. The view that OM stabilization is dominated by the selective preservation of recalcitrant organic components that accumulate in proportion to their chemical properties can no longer be accepted. In contrast, our analysis of mechanisms shows that: (i) the soil biotic community is able to disintegrate any OM of natural origin; (ii) molecular recalcitrance of OM is relative, rather than absolute; (iii) recalcitrance is only important during early decomposition and in active surface soils; while (iv) during late decomposition and in the subsoil, the relevance of spatial inaccessibility and organo‐mineral interactions for SOM stabilization increases. We conclude that major difficulties in the understanding and prediction of SOM dynamics originate from the simultaneous operation of several mechanisms. We discuss knowledge gaps and promising directions of future research.
Neotropical diversification: the effects of a complex history on diversity within the poison frog genus Dendrobates
Authors: Noonan Brice P. , Wray Kenneth P. 
Published: May 2006

AbstractAim  We study the Neotropical poison frogs of the genus Dendrobates Wagler, 1830 in order to clarify their phylogenetic relationships and biogeographical history. The genus Dendrobates is an excellent taxon for examining patterns of Neotropical diversification as the four major species groups appear to correspond roughly to distinct geographical regions: (1) trans‐Andean, (2) Andean foreland, (3) Brazilian Shield and (4) Guianan Shield/Central America. In order to test the agreement of five of the most prominent hypotheses of Amazonian diversification, phylogenetic patterns were examined for agreement with patterns predicted by these hypotheses.Location  Central and South AmericaMethods  The phylogenetic relationships of the genus Dendrobates were examined from novel and existing (GenBank) sequences of four mitochondrial loci totalling c. 1400 bp from 40 specimens of 22 different species using maximum parsimony and Bayesian methods. Results were compared with traditional taxonomic arrangements by means of SH tests. Phylogenetic relationships and genetic distances were used to test the adequacy of various diversification hypotheses.Results  Phylogenetic analyses support the restructuring of two species groups of Dendrobates and the creation of a new species group. Statistical tests of the traditional taxonomic arrangement indicate a significantly bad fit to the molecular data. This restructuring has important implications for the understanding of the historical biogeography of Dendrobates. Biogeographical patterns within this genus suggest that a complex interaction of biotic and abiotic factors since the Eocene have produced the diversity observed today.Main conclusions  The current classification of Dendrobates into discrete species groups does not accurately reflect evolutionary history. Data presented here strongly support a monophyletic Brazilian Shield lineage whose members have previously been split among the quinquevittatus and tinctorius groups. Furthermore, previous attempts at elucidating the historical biogeography of this genus were compromised by incomplete sampling and conclusions drawn from a paraphyletic ingroup. Our findings demonstrate a role for numerous hypotheses of diversification (e.g. river, refuge, disturbance–vicariance) in the history of Dendrobates, supporting previous warnings about the dangers of over‐simplification in the study of Neotropical diversification.
Satellite‐based mapping of the growing season and bioclimatic zones in Fennoscandia
Authors: Karlsen Stein Rune , Elvebakk Arve , Høgda Kjell Arild , Johansen Bernt 
Published: May 2006

ABSTRACTAim  To test whether satellite‐derived NDVI values obtained during the growing season as delimited by the onset of phenological phases can be used to map bioclimatically a large region such as Fennoscandia.Location  Fennoscandia north of about 58° N and neighbouring parts of NW Russia.Methods  Phenology data on birch from 15 research stations and the half‐monthly GIMMS‐NDVI data set with 8 × 8 km2 resolution from the period 1982–2002 were used to characterize the growing season. To link surface phenology with NDVI data, new algorithms on a pixel‐by‐pixel basis that show high correlation with phenophases on birch were developed. Then, time‐integrated values (TI NDVI) during the phenologically defined growing season were computed to produce a bioclimatological map of Fennoscandia, which was tested and correlated with growing degree days (GDD) obtained from 20 meteorological stations. The map was also compared vs. traditional bioclimatic maps, and analysed for error factors distorting NDVI values.Results  The correlation between GDD and TI NDVI data during the phenologically defined growing season was very high. Therefore, the TI NDVI map could be presented as a bioclimatic map reflecting GDD. However, several major areas have interfering factors distorting NDVI values, such as the pixel heterogeneity caused by the altitudinal mosaic in western Norway, the mosaic of lakes in southeastern Finland, and the agriculture‐dominated areas in southern Fennoscandia.Main conclusions  TI NDVI data from the phenologically defined growing season during 1982–2002 in Fennoscandia can be processed as a bioclimatic map reflecting GDD, except for the areas distorting NDVI values by their strong ground‐cover heterogeneity.
Monetary Policy, Expectations and Commitment*
Authors: Evans George W. , Honkapohja Seppo 
Published: May 2006

AbstractCommitment in monetary policy leads to equilibria that are superior to those from optimal discretionary policies. A number of interest‐rate reaction functions and instrument rules have been proposed to implement or approximate commitment policy. We assess these rules in terms of whether they lead to a rational expectations equilibrium that is both locally determinate and stable under adaptive learning by private agents. A reaction function that appropriately depends explicitly on private sector expectations performs particularly well on both counts.
Design and Planned Analyses of an Ongoing Randomized Trial Assessing the Preventive Effect of Helicobacter pylori Eradication on Occurrence of New Gastric Carcinomas After Endoscopic Resection
Authors: Kikuchi Shogo , Kato Mototsugu , Katsuyama Tsutomu , Tominaga Suketami , Asaka Masahiro 
Published: May 2006

AbstractBackground:  A causal relationship between Helicobacter pylori infection and gastric cancer has been established. A nonrandomized study has shown eradication of H. pylori after endoscopic resection (ER) of early gastric cancer inhibits development of new carcinomas.Subjects and Methods:  Eligible subjects are patients with H. pylori infection who are newly diagnosed with early gastric cancer and plan to have ER or who are in the post‐resection follow‐up phase after ER time of enrollment. Patients are randomly allocated to the eradication or the control arms (no eradication and standard of care). Patients will be evaluated by endoscopy at 0.5, 1, 2, and 3 years after randomization. Diagnosis of a new carcinoma at another site of the stomach is defined as primary endpoint, and recurrence of tumors at the resection site as a secondary endpoint. In addition to intention‐to‐treat and per‐protocol analyses using proportional hazards models, time to recurrence will be compared between treatment and control using multiple logistic regression analyses. In the latter two situations, the models will be adjusted for the factors exerting significant influences on the results.Results:  Five hundred and forty‐two subjects have been enrolled into the study and are being followed‐up.Conclusions:  This study will have the statistical power to demonstrate whether H. pylori eradication therapy exerts any clinically relevant inhibitory effects on occurrence or recurrence of gastric cancer. In addition, it will be able to test the hypothesis that H. pylori infection is a promoter in gastric carcinogenesis.
Presurgical Language fMRI in Patients with Drug‐resistant Epilepsy: Effects of Task Performance
Authors: Weber Bernd , Wellmer Jörg , Schür Simone , Dinkelacker Vera , Ruhlmann Jürgen , Mormann Florian , Axmacher Nikolai , Elger Christian E. , Fernández Guillén 
Published: May 2006

Summary:  Purpose: To determine whether language functional magnetic resonance imaging (fMRI) before epilepsy surgery can be similarly interpreted in patients with greatly different performance levels. Methods: An fMRI paradigm using a semantic decision task with performance control and a perceptual control task was applied to 226 consecutive patients with drug‐resistant localization‐related epilepsy during their presurgical evaluations. The volume of activation and lateralization in an inferior frontal and a temporoparietal area was assessed in correlation with individual performance levels. Results: We observed differential effects of task performance on the volume of activation in the inferior frontal and the temporoparietal region of interest, but performance measures did not correlate with the lateralization of activation. Conclusions:
fMRI, as applied here, in patients with a wide range of cognitive abilities, can be interpreted regarding language lateralization in a similar way.
Pregabalin Exerts Oppositional Effects on Different Inhibitory Circuits in Human Motor Cortex: A Double‐blind, Placebo‐controlled Transcranial Magnetic Stimulation Study
Authors: Lang Nicolas , Sueske Elke , Hasan Alkomiet , Paulus Walter , Tergau Frithjof 
Published: May 2006

Summary: Purpose:To explore acute effects of pregabalin (PGB) on human motor cortex excitability with transcranial magnetic stimulation (TMS). Methods:PGB, 600 mg/day, was orally administered in 19 healthy subjects twice daily in a randomized, double‐blind, placebo‐controlled crossover design. Several measures of motor cortex excitability were tested with single‐ and paired‐pulse TMS. Results:Mean short‐interval intracortical inhibition (SICI) was reduced after PGB (74 ± 7% of unconditioned response) compared with placebo (60 ± 6% of unconditioned response). In contrast, mean long‐interval intracortical inhibition (LICI) was increased by PGB (26 ± 4% of unconditioned response) compared with placebo (45 ± 8% of unconditioned response), and mean cortical silent period (CSP) showed an increase from 139 ± 8 ms or 145 ± 8 ms after placebo to 162 ± 7 ms or 161 ± 10 ms after PGB. Motor thresholds, intracortical facilitation, and corticospinal excitability were unaffected. Conclusions:The observed excitability changes with oppositional effects on SICI and LICI or CSP suggest γ‐aminobutyric acid (GABA)B‐receptor activation. They are markedly distinct from those induced by gabapentin, although both PGB and gabapentin are thought to mediate their function by binding to the α(2)‐δ subunit of voltage‐gated calcium channels. Conversely, the TMS profile of PGB shows striking similarities with the pattern evoked by the GABA‐reuptake inhibitor tiagabine.
Incidence and Predictors of Seizures in Patients with Alzheimer's Disease
Authors: Amatniek Joan C. , Hauser W. Allen , DelCastillo‐Castaneda Carrie , Jacobs Diane M. , Marder Karen , Bell Karen , Albert Marilyn , Brandt Joseph , Stern Yaakov 
Published: May 2006

Summary:  Purpose: To determine cumulative incidence and predictors of new‐onset seizures in mild Alzheimer's disease (AD) with a cohort followed prospectively. Limited information is available on the incidence of seizures, and no reports exist of seizure predictors in AD patients. Methods: Mild AD patients were prospectively followed at 6‐month intervals to estimate incidence of unprovoked seizures, compare age‐specific risk of unprovoked seizures with population norms, and identify characteristics at baseline (demographics, duration and severity of AD, physical and diagnostic test findings, and comorbid medical and psychiatric conditions) influencing unprovoked seizure risk. Review of study charts and medical records supplemented coded end‐point data. Results: The cumulative incidence of unprovoked seizures at 7 years was nearly 8%. In all age groups, risk was increased compared with a standard population, with an 87‐fold increase in the youngest group (age 50–59 years) and more than a threefold increase in the oldest group (age 85+ years). In multivariate modeling, independent predictors of unprovoked seizures were younger age [relative risk (RR), 0.89 per year increase in age; 95% confidence interval (CI), 0.82–0.97], African‐American ethnic background (RR, 7.35; 95% CI, 1.42–37.98), more‐severe dementia (RR, 4.15; 95% CI, 1.06–16.27), and focal epileptiform findings on electroencephalogram (EEG) (RR, 73.36; 95% CI, 1.75–3075.25). Conclusions: Seizure incidence is increased in people starting with mild‐to‐moderate AD. Younger individuals, African Americans, and those with more‐severe disease or focal epileptiform findings on EEG were more likely to have unprovoked seizures.
Peripheral Blood Mononuclear Cells from Individuals Infected with Human T-Cell Lymphotropic Virus Type 1 Have a Reduced Capacity To Respond to Recall Antigens
Authors: Mascarenhas Rita Elizabeth , Brodskyn Cláudia , Barbosa Geisa , Clarêncio Jorge , Andrade-Filho Antônio Souza , Figueiroa Frederico , Galvão-Castro Bernardo , Grassi Fernanda 
Published: May 2006

ABSTRACT

Evidence indicates that human T-cell lymphotropic virus type 1 (HTLV-1) infection leads to chronic immunosuppression and a greater susceptibility to infectious diseases. Spontaneous in vitro proliferation of peripheral blood mononuclear cells (PBMC) is an important immunological feature of HTLV-1-infected individuals. However, the association between spontaneous proliferation and immunosuppression is not clear. In this study, we evaluated the cellular immune responses of PBMC from 58 asymptomatic HTLV-1-infected individuals with PBMC showing or not showing spontaneous proliferation. Individuals with PBMC that spontaneously proliferated had increased proportions of CD4 T cells expressing CD45RO and dramatically reduced responses to recall antigens. In addition, frequencies of positive responses to recall antigens were also decreased in HTLV-infected individuals without spontaneous proliferation of PBMC. There was a polyclonal expansion of multiple T-cell receptor Vβ families of CD4
+
T lymphocytes in patients with spontaneous proliferation. We observed that HTLV-1 induced an immunosuppression characterized by a decrease in the stimulation index to a recall antigen, even in individuals who did not present spontaneous proliferation. On the other hand, only patients with PBMC presenting spontaneous proliferation showed polyclonal activation and increased proportion of CD4 T cells expressing CD45RO.
Lymphatic Tissue Fibrosis Is Associated with Reduced Numbers of Naïve CD4
+
T Cells in Human Immunodeficiency Virus Type 1 Infection
Authors: Schacker Timothy W. , Brenchley Jason M. , Beilman Gregory J. , Reilly Cavan , Pambuccian Stefan E. , Taylor Jodie , Skarda David , Larson Matthew , Douek Daniel C. , Haase Ashley T. 
Published: May 2006

ABSTRACT

The organized structure of lymphatic tissues (LTs) constitutes a microenvironment referred to as a niche that plays a critical role in immune system homeostasis by promoting cellular interactions and providing access to cytokines and growth factors on which cells are dependent for survival, proliferation, and differentiation. In chronic human immunodeficiency virus type 1 (HIV-1) infection, immune activation and inflammation result in collagen deposition and disruption of this LT niche. We have previously shown that these fibrotic changes correlate with a reduction in the size of the total population of CD4
+
T cells. We now show that this reduction is most substantial within the naïve CD4
+
T-cell population and is in proportion to the extent of LT collagen deposition in HIV-1 infection. Thus, the previously documented depletion of naïve CD4
+
T cells in LTs in HIV-1 infection may be a consequence not only of a decreased supply of thymic emigrants or chronic immune activation but also of the decreased ability of those cells to survive in a scarred LT niche. We speculate that LT collagen deposition might therefore limit repopulation of naïve CD4
+
T cells with highly active antiretroviral therapy, and thus, additional treatments directed to limiting or reversing inflammatory damage to the LT niche could potentially improve immune reconstitution.
Production of an Anti-Severe Acute Respiratory Syndrome (SARS) Coronavirus Human Monoclonal Antibody Fab Fragment by Using a Combinatorial Immunoglobulin Gene Library Derived from Patients Who Recovered from SARS
Authors: Liu Jinye , Shao Hongxia , Tao Yanlin , Yang Bin , Qian Lisheng , Yang Xiaoli , Cao Brian , Hu Gengxi , Tachibana Hiroshi , Cheng Xunjia 
Published: May 2006

ABSTRACT

A combinatorial human immunoglobulin gene library was constructed from the peripheral lymphocytes of two patients who recovered from severe acute respiratory syndrome (SARS). The library was screened for the production of Fab antibody fragments to a recombinant spike protein of SARS-associated coronavirus (SARS-CoV). One Fab clone, AS3-3, reacted with the spike protein in an enzyme-linked immunosorbent assay. The dissociation constant of AS3-3 was 1.98 × 10
−8
M. Immunofluorescent microscopy revealed that it reacted with SARS-CoV-infected cells. The library seems to be a potent tool for the production of human antibodies to SARS-CoV.
Luminescence différée d'une solution organique vitreuse photoactivée et transition vitreuse
Authors: Ceccaldi D. 
Published: May 2006

A general kinetic theory is used to explain the shapes of photoionized sample luminescence curves perturbed by thermal jumps (Δ ∼ 1 K, rise time ∼ 1 s). The samples studied are photoactivated organic vitreous solutions of TMPD/MCH 10−3 M and TMPD/3-MP 10−3 M. The experiments are performed within a temperature range (63–91 K) which includes the glass transition temperature Tg. It is shown that there is a slow diffusion of the trapped electrons towards the cation and competition between thermal detrapping and tunneling. The tunneling/thermal detrapping ratio Y is not time dependent during an isothermal luminescence and is only slowly temperature dependent if T ≤ Ty. Ty is very close to Tg. For T > Ty, Y decreases rapidly with T. The activation energy for thermal detrapping shows a maximum when the temperature reaches [Formula: see text] The glass transition temperature Tg may therefore be defined empirically as:[Formula: see text]Finally we obtain a glassy matrix relaxation time, τ, which decreases with T.
The Antalya 5 December 2002 Storm: Observations and Model Analysis
Authors: Kotroni V. , Lagouvardos K. , Defer E. , Dietrich S. , Porcù F. , Medaglia C. M. , Demirtas M. 
Published: May 2006

Abstract
In the frame of this work, the storm that occurred on 5 December 2002 in Antalya, located on the southwestern Mediterranean Sea coast of Turkey, is analyzed. More than 230 mm of 24-h-accumulated rainfall have been reported during the event that produced floods in the area. The analysis is based on the results of model simulations with the fifth-generation Pennsylvania State University–NCAR Mesoscale Model (MM5). Observational data provided by the Tropical Rainfall Measuring Mission (TRMM) sensors (including the Lightning Imaging Sensor and TRMM Microwave Imager), Special Sensor Microwave Imager (SSM/I), Meteosat-7, and Met Office Arrival Time Difference (ATD) lightning network are used for both the comparison with the model results and also for the characterization of the storm. The synergetic use of all of this information was crucial for the description of the event. The maximum of precipitation was associated with the warm and moist air masses driven by a low-level jet over the area and impinging over the orographic barriers. The improvement of representation of the humidity field in the model initial conditions, through a simple technique of humidity adjustment based on satellite rainfall estimates, resulted in an improvement of the prediction of the timing and quantity of the precipitation maxima during the event.
Local Structure of Turbulence in Stably Stratified Boundary Layers
Authors: Sorbjan Zbigniew 
Published: May 2006

Abstract
The “flux based” local scaling in the stably stratified boundary layer is valid only in cases with strong, continuous turbulence, when the gradient Richardson number Ri is constant and subcritical. To extend the local similarity approach to cases with weak turbulence (very stable regime), the “gradient based” local scaling is introduced and discussed in the paper. Both types of local scaling, the flux based and the gradient based, are tested based on the data, collected from a 60-m tower during the Cooperative Atmosphere–Surface Exchange Study-1999 (CASES-99). The obtained results show that the gradient-based scaling provides a useful framework for the treatment of cases with both strong and weak turbulence and overcritical Richardson numbers.