bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cytokine polymorphisms influence treatment outcomes in SLE patients treated with antimalarial drugs
Authors: López Patricia , Gómez Jesús , Mozo Lourdes , Gutiérrez Carmen , Suárez Ana 
Published: February 2006

AbstractAntimalarial agents have been widely used as disease-modifying antirheumatic drugs in the treatment of systemic lupus erythematosus (SLE) and other rheumatological diseases, although their mechanism of action has not yet been fully defined. It is known, however, that effective response to treatment is variable among patients. Thus, the identification of genetic predictors of treatment response would provide valuable information for therapeutic intervention. The aim of the present study was to analyze the effect of antimalarial treatment on tumor necrosis factor (TNF)α serum levels and evaluate the possible influence of TNFα and IL-10 functional genetic polymorphisms on the response to antimalarial drugs. To this end, TNFα serum levels were quantified in 171 SLE patients and 215 healthy controls by ELISA techniques and polymorphisms at positions -1,082 and -308 of the IL-10 and TNFα gene promoterswere determined by PCR amplification followed by hybridization with fluorescent-labeled allele-specific probes in 192 SLE patients and 343 matched controls. Data were related to clinical features and treatment at the time of sampling and during the course of the disease. Results showed a significantly higher amount of serum TNFα in the entire SLE population compared with controls. However, TNFα serum levels correlated negatively with the use of antimalarial treatment during at least three months before sampling. Patients under single or combined treatment with these drugs had TNFα serum levels similar to healthy controls, whereas untreated patients and those under corticosteroid or immunosuppressive therapies had increased amounts of this cytokine. This suggests, however, that antimalarial-mediated inhibition of TNFα was only significant in patients who were genetically high TNFα or low IL-10 producers. In addition, evaluation of SLE patients administered antimalarial drugs for three or more years who did not require any other specific SLE treatment indicates that patients with the combined genotype low IL-10/high TNFα are the best responders to antimalarial therapy, developing mild disease with a good course under this treatment. In conclusion, we proposed that an antimalarial-mediated downregulation of TNFα levels in SLE patients is influenced by polymorphisms at IL-10 and TNFα promoters. Our results may thus find important clinical application through the identification of patients who are the most likely to benefit from antimalarial therapy.
Lactate versus non-lactate metabolic acidosis: a retrospective outcome evaluation of critically ill patients
Authors: Gunnerson Kyle J , Saul Melissa , He Shui , Kellum John A 
Published: February 2006

Abstract
Introduction
Acid–base abnormalities are common in the intensive care unit (ICU). Differences in outcome exist between respiratory and metabolic acidosis in similar pH ranges. Some forms of metabolic acidosis (for example, lactate) seem to have worse outcomes than others (for example, chloride). The relative incidence of each type of disorder is unknown. We therefore designed this study to determine the nature and clinical significance of metabolic acidosis in critically ill patients.

Methods
An observational, cohort study of critically ill patients was performed in a tertiary care hospital. Critically ill patients were selected on the clinical suspicion of the presence of lactic acidosis. The inpatient mortality of the entire group was 14%, with a length of stay in hospital of 12 days and a length of stay in the ICU of 5.8 days.

Results
We reviewed records of 9,799 patients admitted to the ICUs at our institution between 1 January 2001 and 30 June 2002. We selected a cohort in which clinicians caring for patients ordered a measurement of arterial lactate level. We excluded patients in which any necessary variable required to characterize an acid–base disorder was absent. A total of 851 patients (9% of ICU admissions) met our criteria. Of these, 548 patients (64%) had a metabolic acidosis (standard base excess < -2 mEq/l) and these patients had a 45% mortality, compared with 25% for those with no metabolic acidosis (p < 0.001). We then subclassified metabolic acidosis cases on the basis of the predominant anion present (lactate, chloride, or all other anions). The mortality rate was highest for lactic acidosis (56%); for strong ion gap (SIG) acidosis it was 39% and for hyperchloremic acidosis 29% (p < 0.001). A stepwise logistic regression model identified serum lactate, SIG, phosphate, and age as independent predictors of mortality.

Conclusion
In critically ill patients in which a measurement of lactate level was ordered, lactate and SIG were strong independent predictors of mortality when they were the major source of metabolic acidosis. Overall, patients with metabolic acidosis were nearly twice as likely to die as patients without metabolic acidosis.
Dopexamine and norepinephrine versus epinephrine on gastric perfusion in patients with septic shock: a randomized study [NCT00134212]
Authors: Seguin Philippe , Laviolle Bruno , Guinet Patrick , Morel Isabelle , Mallédant Yannick , Bellissant Eric 
Published: February 2006

Abstract
Introduction
Microcirculatory blood flow, and notably gut perfusion, is important in the development of multiple organ failure in septic shock. We compared the effects of dopexamine and norepinephrine (noradrenaline) with those of epinephrine (adrenaline) on gastric mucosal blood flow (GMBF) in patients with septic shock. The effects of these drugs on oxidative stress were also assessed.

Methods
This was a prospective randomized study performed in a surgical intensive care unit among adults fulfilling usual criteria for septic shock. Systemic and pulmonary hemodynamics, GMBF (laser-Doppler) and malondialdehyde were assessed just before catecholamine infusion (T0), as soon as mean arterial pressure (MAP) reached 70 to 80 mmHg (T1), and 2 hours (T2) and 6 hours (T3) after T1. Drugs were titrated from 0.2 μg kg-1 min-1 with 0.2 μg kg-1 min-1 increments every 3 minutes for epinephrine and norepinephrine, and from 0.5 μg kg-1 min-1 with 0.5 μg kg-1 min-1 increments every 3 minutes for dopexamine.

Results
Twenty-two patients were included (10 receiving epinephrine, 12 receiving dopexamine–norepinephrine). There was no significant difference between groups on MAP at T0, T1, T2, and T3. Heart rate and cardiac output increased significantly more with epinephrine than with dopexamine–norepinephrine, whereas. GMBF increased significantly more with dopexamine–norepinephrine than with epinephrine between T1 and T3 (median values 106, 137, 133, and 165 versus 76, 91, 90, and 125 units of relative flux at T0, T1, T2 and T3, respectively). Malondialdehyde similarly increased in both groups between T1 and T3.

Conclusion
In septic shock, at doses that induced the same effect on MAP, dopexamine–norepinephrine enhanced GMBF more than epinephrine did. No difference was observed on oxidative stress.
Idiomatic Syntactic Constructions and Language Learning
Authors: Kaschak Michael P. , Saffran Jenny R. 
Published: February 2006

AbstractThis article explores the influence of idiomatic syntactic constructions (i.e., constructions whose phrase structure rules violate the rules that underlie the construction of other kinds of sentences in the language) on the acquisition of phrase structure. In Experiment 1, participants were trained on an artificial language generated from hierarchical phrase structure rules. Some participants were given exposure to an idiomatic construction (IC) during training, whereas others were not. Under some circumstances, the presence of an idiomatic construction in the input aided learners in acquiring the phrase structure of the language. Experiment 2 provides a replication of the first experiment and extends the findings by showing that idiomatic constructions that strongly violate the predictive dependencies that define the phrase structure of the language do not aid learners in acquiring the structure of the language. Together, our data suggest that (a) idiomatic constructions aid learners in acquiring the phrase structure of a language by highlighting relevant structural elements in the language, and (b) such constructions are useful cues to learning to the extent that learners can keep their knowledge of the idiomatic construction separate from their knowledge of the rest of the language.
The Role of Functionality in the Mental Representations of Engineering Students: Some Differences in the Early Stages of Expertise
Authors: Moss Jarrod , Kotovsky Kenneth , Cagan Jonathan 
Published: February 2006

AbstractAs engineers gain experience and become experts in their domain, the structure and content of their knowledge changes. Two studies are presented that examine differences in knowledge representation among freshman and senior engineering students. The first study examines recall of mechanical devices and chunking of components, and the second examines whether seniors represent devices in a more abstract functional manner than do freshmen. The most prominent differences between these 2 groups involve their representation of the functioning of groups of electromechanical components and how these groups of components interact to produce device behavior. Seniors are better able to construct coherent representations of devices by focusing on the function of sets of components in the device. The findings from these studies highlight some ways in which the structure and content of mental representations of design knowledge differ during the early stages of expertise acquisition.
Modeling Recognition Memory Using the Similarity Structure of Natural Input
Authors: Lacroix Joyca P. W. , Murre Jaap M. J. , Postma Eric O. , van den Herik H. Jaap 
Published: February 2006

AbstractThe natural input memory (NIM) model is a new model for recognition memory that operates on natural visual input. A biologically informed perceptual preprocessing method takes local samples (eye fixations) from a natural image and translates these into a feature‐vector representation. During recognition, the model compares incoming preprocessed natural input to stored representations. By complementing the recognition memory process with a perceptual front end, the NIM model is able to make predictions about memorability based directly on individual natural stimuli. We demonstrate that the NIM model is able to simulate experimentally obtained similarity ratings and recognition memory for individual stimuli (i.e., face images).
Deferred Interpretations: Why Starting Dickens is Taxing but Reading Dickens Isn't
Authors: McElree Brian , Frisson Steven , Pickering Martin J. 
Published: February 2006

AbstractComprehenders often need to go beyond conventional word senses to obtain an appropriate interpretation of an expression. We report an experiment examining the processing of standard metonymies (The gentleman read Dickens) and logical metonymies (The gentleman began Dickens), contrasting both to the processing of control expressions with a conventional interpretation (The gentleman met Dickens). Eye movement measures during reading indicated that standard (producer‐for‐product) metonymies were not more costly to interpret than conventional expressions, but logical metonymies were more costly to interpret than both standard metonymies and conventional expressions. These results indicate that constructing alternative senses is sometimes taxing and that not all types of deferred interpretations are processed in the same way. The results suggest that a critical factor in determining the attendant cost of constructing alternative senses is whether compositional operations must generate unexpressed semantic structure to realize an extended sense of an expression.
Animal Foraging and the Evolution of Goal‐Directed Cognition
Authors: Hills Thomas T. 
Published: February 2006

AbstractForaging‐ and feeding‐related behaviors across eumetazoans share similar molecular mechanisms, suggesting the early evolution of an optimal foraging behavior called area‐restricted search (ARS), involving mechanisms of dopamine and glutamate in the modulation of behavioral focus. Similar mechanisms in the vertebrate basal ganglia control motor behavior and cognition and reveal an evolutionary progression toward increasing internal connections between prefrontal cortex and striatum in moving from amphibian to primate. The basal ganglia in higher vertebrates show the ability to transfer dopaminergic activity from unconditioned stimuli to conditioned stimuli. The evolutionary role of dopamine in the modulation of goal‐directed behavior and cognition is further supported by pathologies of human goal‐directed cognition, which have motor and cognitive dysfunction and organize themselves, with respect to dopaminergic activity, along the gradient described by ARS, from perseverative to unfocused. The evidence strongly supports the evolution of goal‐directed cognition out of mechanisms initially in control of spatial foraging but, through increasing cortical connections, eventually used to forage for information.
Formalization and Analysis of Reasoning by Assumption
Authors: Bosse Tibor , Jonker Catholijn M. , Treur Jan 
Published: February 2006

AbstractThis article introduces a novel approach for the analysis of the dynamics of reasoning processes and explores its applicability for the reasoning pattern called reasoning by assumption. More specifically, for a case study in the domain of a Master Mind game, it is shown how empirical human reasoning traces can be formalized and automatically analyzed against dynamic properties they fulfill. To this end, for the pattern of reasoning by assumption a variety of dynamic properties have been specified, some of which are considered characteristic for the reasoning pattern, whereas some other properties can be used to discriminate among different approaches to the reasoning. These properties have been automatically checked for the traces acquired in experiments undertaken. The approach turned out to be beneficial from two perspectives. First, checking characteristic properties contributes to the empirical validation of a theory on reasoning by assumption. Second, checking discriminating properties allows the analyst to identify different classes of human reasoners.
Pretargeting For The Implantation Of Stimulation Electrodes Into The Subthalamic Nucleus:A Comparative Study Of Magnetic Resonance Imaging And Ventriculography
Authors: Breit Sorin , LeBas Jean-Francois , Koudsie Adnan , Schulz Jo¨rg , Benazzouz Abdelhamid , Pollak Pierre , Benabid Alim-Louis 
Published: February 2006

Abstract

OBJECTIVE:
The optimal imaging modality for preoperative targeting of the subthalamic nucleus (STN) for high-frequency stimulation is controversially discussed. Commonly used methods were stereotactic magnetic resonance imaging (MRI), stereotactic ventriculography, and fusion between MRI and stereotactic computer tomography. All of these techniques not only have their own advantages but also specific limitations and drawbacks. The purpose of this study was to evaluate the accuracy of the preoperative MRI targeting as compared with ventriculography in terms of both the STN target as well as the internal landmarks.

METHODS:
Thirty patients with Parkinson's disease who underwent bilateral surgery for STN-high-frequency stimulation received both stereotactic ventriculography and stereotactic MRI. The theoretical target was determined by each of these two imaging modalities. The final electrode placement was performed after extensive electrophysiological evaluation using microrecording and microstimulation. The real target was assumed to be given by the electrode contact with the best clinical result assessed by the United Parkinson's Disease Rating Scale in the postoperative follow-up. In addition, the coordinates of the two landmarks, anterior commissure and posterior commissure, were determined using both imaging methods.

RESULTS:
The mean targeting error was 4.1 ± 1.7 mm (mean ± standard deviation) for MRI and 2.4 ± 1.1 mm for ventriculography (P &lt; 0.0001). The mean target mismatch between the two imaging methods was 2.9 ± 1.2 mm. The length of the anterior commissure-posterior commissure distance differed significantly (P &lt; 0.0001) between MRI (27.6 ± 1.6 mm) and ventriculography (25.0 ± 1.3 mm). The mismatch was mainly induced by an anterior diplacement of the anterior commissure by 1.9 ± 2.2 mm (P &lt; 0.0001) in MRI determination, as compared with ventriculography.

CONCLUSION:
Our findings show that the indirect targeting of the STN using coordinates based on radiological landmarks is more accurate than the direct targeting using anatomic visualization of the target structure. Regardless of the imaging procedure, electrophysiological mapping is required for optimal electrode placement, although in 20% of cases, the target determined by MRI falls out of the radius explored by electrophysiology.
Endoscopic Resection of Hypothalamic Hamartoma Using a Novel Variable Aspiration Tissue Resector
Authors: Lekovic Gregory P. , Gonzalez L. Fernando , Feiz-Erfan Iman , Rekate Harold L. 
Published: February 2006

AbstractOBJECTIVE:We present a novel variable aspiration tissue resector for use with neuroendoscopy.METHODS:Two patients, 4 and 14 years old, respectively, presented with intractable gelastic seizures refractory to maximal medical therapies. Magnetic resonance imaging showed mass lesions of the third ventricle consistent with hypothalamic hamartoma.RESULTS:The patients underwent magnetic resonance imaging wand-guided endo-scopic resection of the tumor with the Suros novel variable aspiration tissue resector. There were no device-associated complications or adverse events. The hamartoma was disconnected in one patient, and gross total resection was achieved in the other.CONCLUSION:Endoscopy for tumor resection is still frustrated by the lack of surgical tools, such as ultrasonic aspirators, comparable with those available for use during open procedures. The variable-aspiration tissue resector reported here can be used to resect tumor tissue safely. These two cases demonstrate that gross total resection of small hypothalamic hamartomas is feasible with minimal morbidity through an endo-scopic approach.
The Occipital Artery:Amicroanatomical Study
Authors: Alvernia Jorge E. , Fraser Kenneth , Lanzino Giuseppe 
Published: February 2006

Abstract

OBJECTIVE:
We performed a systematic microanatomical study of the occipital artery (OA) and its branches to describe the course, diameter, and branches of this vessel as well as the presence and pattern of anastomotic channels between the OA and the vertebral artery.

METHODS:
Twelve occipital arteries (6 adult cadaveric heads injected with colored latex) were studied using the surgical microscope. Particular attention was given to the course and branching pattern of the artery as well as the presence and type of anastomotic channels between the occipital artery and vertebral artery.

RESULTS:
Based upon anatomical considerations, the course of the occipital artery was divided into three segments. The first, or digastric segment, extends from the origin to the exit off the occipital groove of the mastoid process. The second segment, or suboccipital, extends from the occipital groove to the superior nuchal line. The third, or terminal segment, corresponds to the subgaleal segment just above the superior nuchal line up to the vertex. Two main descending branches of the second segment or suboccipital were identified. The superficial descending branch (SDB) runs between the splenium capitis and semispinalis capitis while the deep descending branch (DDB) enters the suboccipital triangle. Anastomotic vessels between one of these two descending branches and branches of the vertebral artery were found in 11 out of the 12 OAs dissected (91%).

CONCLUSION:
Detailed knowledge of the OA anatomy is helpful in choosing this vessel as a donor for extra-intracranial bypasses. More importantly, knowledge and understanding of the type and pattern of anastomoses between the OA and the vertebral artery are critical to avoid disastrous complications (i.e., posterior circulation stroke) during embolization of vascular or neoplastic processes fed by distal OA branches.
Annealing effects, anomalous dielectric properties and conductivity of As-diluted lead phosphate Pb3(P1–xAsxO4)2
Authors: Baranov Anatolii I. , Bismayer Ulrich 
Published: February 2006

Abstract
The influence of annealing (thermal treatment) in different atmospheres on the conductivity and dielectric properties of As-diluted lead phosphate Pb3(P
1–x
As
x
O4)2was studied. The anomalous low frequency dielectric behavior of these crystals was found to be related to their conductive properties. A model invoking the dissociation of polar impurity complexes is proposed in order to explain the observed giant dielectric maxima and their strong frequency dispersion. It was found that extrinsic proton conductivity dominates the dielectric properties in the temperature range 350–900 K in Pb3(P
1–x
As
x
O4)2 and that annealing in wet atmosphere increases the protonic conductivity by more than one order of magnitude.
The transformation mechanism of the sodalite- to the melilite-topology: Thermal expansion and decomposition of bicchulite-type to melilite-type compounds
Authors: Peters Lars , Knorr Karsten , Katzke Hannelore , Knapp Michael , Depmeier Wulf 
Published: February 2006

Abstract
The mineral bicchulite, |Ca8(OH)8|[Al8Si4O24]-SOD, has the sodalite-(SOD-)type structure. At elevated temperatures it decomposes into gehlenite, Ca2Al2SiO7 (melilite-type structure), and water (vapour). We report on the thermal expansion of two bicchulite-type compounds, the mineral bicchulite up to T = 740 K and |Ca6Eu2(OH)8|[Al10Si2O24]-SOD up to T = 1025 K. The expansion mechanism is described. In
situ X-ray powder diffraction experiments were performed to evaluate the thermal decomposition of |Ca6Eu2(OH)8|[Al10Si2O24]-SOD into 4 (Ca1.5Eu0.5)T
1[T
2
2O7] and 4 H2O, with T
i = Al or Si in a ratio of 5 : 1. A structural mechanism for the transformation from the sodalite to the melilite topology is proposed, based on geometrical considerations.
The crystal structure of natural 33R moissanite from Tibet
Authors: Lee Jiann-Shing , Yu Shu-Cheng , Tung Shu-Fang , Bai Wen-Ji , Yang Jing-Sui , Fang Qing-Song , Zhang Zeming 
Published: February 2006

Abstract
The crystal structure of the natural 33R moissanite, recovered as inclusions in chromitites from Luobusa harzburgite in Tibet, was determined from X-ray diffraction data collection by a Nonius CAD-4 four-circle diffractometer. The crystal is trigonal in symmetry with a space group of R3m. Identical to the synthetic specimen, the cell parameters are a = 3.076, c = 83.12 Å for the natural sample. Full-matrix least-squares refinement of the structure, including anisotropic displacement parameters, gave the final R factor of 4.80%.
The bond angles and tetrahedral angle variance of the present crystal structure show that the tetrahedra are quite regular in geometry. The distance between two adjacent c double layers, 2.517 ± 0.001 Å, is slightly shorter than the average h–c distance of 2.523 ± 0.001 Å. With 36% hexagonal double layers, the present 33R moissanite is inferred to crystallize at high temperature condition and thus come from a depth beneath Earth’s crust. The structure refinements of this work indicate that the present moissanite exhibits smaller thermal displacement parameters. Most of the Si—C bond distances parallel to the c axis are longer than other distances. This result as well as longer bond distances of Si—C along c axis may be indicative of a weaker covalent bonding force along this direction.