bluuebunny/crossref_metadata_2025 huggingface dataset:
AUTOMORPHIC EQUIVALENCE PROBLEM FOR FREE ASSOCIATIVE ALGEBRAS OF RANK TWO
Authors: DRENSKY VESSELIN , YU JIE-TAI
Published: March 2007

Let K 〈x,y〉 be the free associative algebra of rank 2 over an algebraically closed constructive field of any characteristic. We present an algorithm which decides whether or not two elements in K 〈x,y〉 are equivalent under an automorphism of K 〈x,y〉. A modification of our algorithm solves the problem whether or not an element in K 〈x,y〉 is a semiinvariant of a nontrivial automorphism. In particular, it determines whether or not the element has a nontrivial stabilizer in Aut K 〈x,y〉.

An algorithm for equivalence of polynomials under automorphisms of ℂ[x,y] was presented by Wightwick. Another, much simpler algorithm for automorphic equivalence of two polynomials in K[x,y] for any algebraically closed constructive field K was given by Makar-Limanov, Shpilrain, and Yu. In our approach we combine an idea of the latter three authors with an idea from the unpublished thesis of Lane used to describe automorphisms which stabilize elements of K 〈x,y〉. This also allows us to give a simple proof of the corresponding result for K[x,y] obtained by Makar-Limanov, Shpilrain, and Yu.
POLYNOMIAL-TIME COMPLEXITY FOR INSTANCES OF THE ENDOMORPHISM PROBLEM IN FREE GROUPS
Authors: CIOBANU LAURA
Published: March 2007

We say the endomorphism problem is solvable for an element W in a free group F if it can be decided effectively whether, given U in F, there is an endomorphism ϕ of F sending W to U. This work analyzes an approach due to Edmunds and improved by Sims. Here we prove that the approach provides an efficient algorithm for solving the endomorphism problem when W is a two-generator word. We show that when W is a two-generator word this algorithm solves the problem in time polynomial in the length of U.

This result gives a polynomial-time algorithm for solving, in free groups, two-variable equations in which all the variables occur on one side of the equality and all the constants on the other side.
STAR-FREE GEODESIC LANGUAGES FOR GROUPS
Authors: HERMILLER SUSAN , HOLT DEREK F. , REES SARAH
Published: March 2007

In this article we show that every group with a finite presentation satisfying one or both of the small cancellation conditions C′(1/6) and C′(1/4) - T(4) has the property that the set of all geodesics (over the same generating set) is a star-free regular language. Star-free regularity of the geodesic set is shown to be dependent on the generating set chosen, even for free groups. We also show that the class of groups whose geodesic sets are star-free with respect to some generating set is closed under taking graph (and hence free and direct) products, and includes all virtually abelian groups.
BOUNDING RIGHT-ARM ROTATION DISTANCES
Authors: CLEARY SEAN , TABACK JENNIFER
Published: March 2007

Rotation distance measures the difference in shape between binary trees of the same size by counting the minimum number of rotations needed to transform one tree to the other. We describe several types of rotation distance where restrictions are put on the locations where rotations are permitted, and provide upper bounds on distances between trees with a fixed number of nodes with respect to several families of these restrictions. These bounds are sharp in a certain asymptotic sense and are obtained by relating each restricted rotation distance to the word length of elements of Thompson's group F with respect to different generating sets, including both finite and infinite generating sets.
GROUPS WITH QUADRATIC-NON-QUADRATIC DEHN FUNCTIONS
Authors: YU. OL'SHANSKII ALEXANDER
Published: March 2007

We construct a finitely presented group G with non-quadratic Dehn function f majorizable by a quadratic function on arbitrary long intervals.
A LEARNING BASED APPROACH TO AUDIO SURVEILLANCE IN HOUSEHOLD ENVIRONMENT
Authors: QIN JIANZHAO , CHENG JUN , WU XINYU , XU YANGSHENG
Published: March 2007

Recently, audio analysis has been proposed by some researchers for surveillance application. Compared with video surveillance, the effectiveness of audio surveillance is not influenced by the occlusions. In this paper, we propose a learning based approach to intelligent audio surveillance in household environment. This approach can be applied to static or mobile audio surveillance systems which work solely or work as the supplements of video surveillance systems. After extracting Mel frequency cepstral coefficients (MFCC) from a 1.0 s waveform, a classifier trained from a labeled dataset using modest AdaBoost is employed to determine whether this waveform is normal or abnormal. The result and simulation show the effectiveness of this approach.
Melatonin inhibits fatty acid-induced triglyceride accumulation in ROS17/2.8 cells: implications for osteoblast differentiation and osteoporosis
Authors: Sanchez-Hidalgo M. , Lu Z. , Tan D.-X. , Maldonado M. D. , Reiter R. J. , Gregerman R. I.
Published: March 2007

Melatonin is produced not only by the pineal gland but by cells of the bone marrow. Moreover, melatonin is known to promote osteogenic differentiation in several cell line models and in multipotential bone marrow mesenchymal stem cells. Fatty acids have been independently shown to direct such cells to acquire the phenotype and molecular characteristics of adipocytes. To examine the effect of melatonin on intracellular triglyceride accumulation, an indicator of adipogenic differentiation in the rat osteoblast-like ROS17/2.8 cell line, cells were incubated with added oleic acid (100 μM), fixed and stained with Oil Red O. Cellular lipid accumulation was quantitated by an Oil Red O method highly specific for triglycerides and expressed as a triglyceride accumulation index (TGAI, triglyceride per cell). Melatonin in nanomolar concentrations inhibited oleic acid-induced triglyceride accumulation. To identify the mechanism by which melatonin reduces triglyceride accumulation, cells were incubated with the two melatonin receptor antagonists, luzindole and S20928, or forskolin, a stimulator of adenylyl cyclase and cAMP production. These compounds prevented the inhibitory effect of melatonin on triglyceride accumulation, indicating that melatonin acts through known melatonin receptor-mediated mechanisms. In view of the previously demonstrated positive effects of melatonin in promoting osteoblastic differentiation in ROS17/2.8 cells and their reciprocal adipocytic differentiation induced by fatty acids, our observations may serve to relate the known age-related decreases of melatonin production, the shift in the bone marrow toward an adipocytic line of cell development, and the development of osteoporosis during aging.
Roles of nitric oxide and angiotensin II in the impaired baroreflex gain of pregnancy
Authors: Daubert Daisy L. , Liu Dongmei , Zucker Irving H. , Brooks Virginia L.
Published: March 2007

The present study tested the hypothesis that nitric oxide (NO) contributes to impaired baroreflex gain of pregnancy and that this action is enhanced by angiotensin II. To test these hypotheses, we quantified baroreflex control of heart rate in nonpregnant and pregnant conscious rabbits before and after: 1) blockade of NO synthase (NOS) with Nω-nitro-l-arginine (20 mg/kg iv); 2) blockade of the angiotensin II AT1receptor with L-158,809 (5 μg·kg−1·min−1iv); 3) infusion of angiotensin II (1 ng·kg−1·min−1nonpregnant, 1.6–4 ng·kg−1·min−1pregnant iv); 4) combined blockade of angiotensin II AT1receptors and NOS; and 5) combined infusion of angiotensin II and blockade of NOS. To determine the potential role of brain neuronal NOS (nNOS), mRNA and protein levels were measured in the paraventricular nucleus, nucleus of the solitary tract, caudal ventrolateral medulla, and rostral ventrolateral medulla in pregnant and nonpregnant rabbits. The decrease in baroreflex gain observed in pregnant rabbits (from 23.3 ± 3.6 to 7.1 ± 0.9 beats·min−1·mmHg−1, P < 0.05) was not reversed by NOS blockade (to 8.3 ± 2.5 beats·min−1·mmHg−1), angiotensin II blockade (to 5.0 ± 1.1 beats·min−1·mmHg−1), or combined blockade (to 12.3 ± 4.8 beats·min−1·mmHg−1). Angiotensin II infusion with (to 5.7 ± 1.0 beats·min−1·mmHg−1) or without (to 8.4 ± 2.4 beats·min−1·mmHg−1) NOS blockade also failed to improve baroreflex gain in pregnant or nonpregnant rabbits. In addition, nNOS mRNA and protein levels in cardiovascular brain regions were not different between nonpregnant and pregnant rabbits. Therefore, we conclude that NO, either alone or via an interaction with angiotensin II, is not responsible for decrease in baroreflex gain during pregnancy.
Effect of muscle interstitial pH on P2X and TRPV1 receptor-mediated pressor response
Authors: Gao Zhaohui , Li Jialiu D. , Sinoway Lawrence I. , Li Jianhua
Published: March 2007

Activation of purinergic P2X receptors and transient receptor potential vanilloid type 1 (TRPV1) on muscle afferent nerve evokes the pressor response. Because P2X and TRPV1 receptors are sensitive to changes in pH, the aim of this study was to examine the effects of muscle acidification on those receptor-mediated cardiovascular responses. In decerebrate rats, the pH in the hindlimb muscle was adjusted by infusing acidic Ringer solutions into the femoral artery. Dialysate was then collected using microdialysis probes inserted into the muscles, and pH was measured. The interstitial pH was 7.53 ± 0.01, 7.22 ± 0.02, 6.94 ± 0.04, and 6.59 ± 0.03 in response to arterial infusion of the Ringer solution at pH 7.4, 6.5, 5.5, and 4.5, respectively. Femoral arterial injection of α,β-methylene-ATP (P2X receptor agonist) in the concentration of 0.25 mM (volume, 0.15–0.25 ml; injection duration, 1 min) at the infused pH of 7.4, 6.5, and 5.5 increased mean arterial pressure (MAP) by 29 ± 2, 24 ± 3, and 21 ± 3 mmHg, respectively ( P < 0.05, pH 5.5 vs. pH 7.4). When pH levels in the infused solution were 7.4, 6.5, 5.5, and 4.5, capsaicin (1 μg/kg), a TRPV1 agonist, was injected into the artery. This elevated MAP by 29 ± 4, 33 ± 2, 35 ± 3, and 40 ± 3 mmHg, respectively ( P < 0.05, pH 4.5 vs. pH 7.4). Furthermore, blocking acid-sensing ion channel (ASIC) blunted pH effects on TRPV1 response. Our data indicate that 1) muscle acidosis attenuates P2X-mediated pressor response but enhances TRPV1 response; 2) exaggerated TRPV1 response may require lower pH in muscle, and the effect is likely to be mediated via ASIC mechanisms. This study provides evidence that muscle pH may be important in modulating P2X and TRPV1 responsiveness in exercising muscle.
Growing Gap in Folic Acid Intake with Respect to Level of Education in the Netherlands
Authors: de Walle H.E.K. , de Jong-van den Berg L.T.W.
Published: March 2007

Objective: To evaluate the prevalence of the awareness of and the behaviour towards folic acid in 2003 and the trend of folic acid use among pregnant Dutch women between 1995 and 2003 with regard to socio-economic status (SES). Method: We conducted 2-yearly cross-sectional studies among pregnant women who filled in a questionnaire during the first or second antenatal visit. The highest achieved level of education was taken as a proxy for SES. Results: In 2003 the general level of folic acid awareness was high but with significant differences relating to SES; a quarter of the lower educated women did not know about folic acid before pregnancy. Of the subjects with a lower SES 20% knew the correct period of use compared with nearly 50% in the higher SES group. The reported correct use of folic acid among the lower educated women has decreased over the past 3 years (22% in 2003), while it has increased for the higher SES groups (59% in 2003), implying larger differences in health. Conclusion: In 2003, 8 years after a mass media campaign, awareness and use of folic acid were increased considerably in comparison with the start of the campaign. However, differences in knowledge and use of folic acid with respect to the level of education had never been so impressive in the Netherlands as in 2003. A once-only campaign has a short-term effect especially for lower educated women. Implementing strategies to promote folic acid use in daily structural health care systems are needed.
Neoadjuvant Radiochemotherapy for Rectal Cancer
Authors: Vini Louiza
Published: March 2007

During the past few decades, significant progress has been achieved in the management of rectal cancer with the introduction of total mesorectal excision. The role of radiotherapy in improving local control and survival has been investigated extensively. Randomized trials of preoperative radiotherapy reported statistically significant lower local recurrence rates with either short regimens (25 Gy in 5 fractions) or conventionally fractionated regimens (45–50 Gy in 25 fractions) and some also showed a survival improvement. Preoperative radiotherapy appears more effective in terms of local control and toxicity compared to postoperative therapy. Several recent studies show that 5-FU-based chemotherapy enhances tumor response to radiotherapy and preoperative chemoradiotherapy is being increasingly used for stage II and III disease.
Conventional CT for the Prediction of an Involved Circumferential Resection Margin in Primary Rectal Cancer
Authors: Wolberink Steven V.R.C. , Beets-Tan Regina G.H. , de Haas-Kock Danielle F.M. , Span Mark M. , van de Jagt Eric J. , van de Velde Cornelis J.H. , Wiggers Theo
Published: March 2007

Purpose: To determine the accuracy of conventional computed tomography (CT) scan in the preoperative prediction of an involved circumferential resection margin (CRM) in primary rectal cancer. Methods: 125 patients with biopsy-proven adenocarcinoma of the rectum underwent CT of the abdomen before undergoing total mesorectal excision. Scans were scored by three observers, differing in experience. The main outcome was yes/no involvement of the CRM. Histology was taken as reference standard. Results: For the most experienced observer, observer A, sensitivity was 46.7% and specificity 92.6%. For observer B, sensitivity was 46.7% and specificity 89.5%. For the least experienced observer C, sensitivity was 43.3% and specificity 92.6%. Inter-observer variability was good between observers A and B (ĸ 0.648), B and C (ĸ 0.648), and intermediate between A and C (ĸ 0.542). Discrepancies occurred in a total of 34 patients; 25 had a CT scan of low technical quality, 10 an anteriorly located distal tumor. Conclusion: Conventional CT scan lacks sensitivity for a clinical use in the preoperative assessment of an involved CRM in primary rectal cancer. Modern multislice spiral CT will probably resolve some of the problems of conventional CT; however, further research is needed to establish its role.
Interleukin-10 Regulates Transforming Growth Factor-β Signaling in Cultured Human Bronchial Epithelial Cells
Authors: Fueki Naoto , Sagara Hironori , Akimoto Kazumi , Ota Mayumi , Okada Takenori , Sugiyama Kumiya , Fueki Makoto , Makino Sohei , Fukuda Takeshi
Published: March 2007

Background: The basic pathological features of bronchial asthma can be explained on the basis of chronic airway inflammation, involving inflammatory cells such as T cells (particularly type 2 helper T, Th2, cells) and mast cells, and airway remodeling. Many aspects of airway remodeling remain unclear at the molecular level. Recent attention has focused on the role of transforming growth factor (TGF)-β, a fibrogenic cytokine, in airway remodeling. Currently available evidence suggests that airway remodeling is caused by an imbalance in regulatory mechanisms mediated by Smads, a family of signal-transducing molecules. Objectives: We studied the effects of the Th2 cytokines interleukin (IL)-5 and granulocyte-macrophage colony-stimulating factor (GM-CSF), and the regulatory cytokine IL-10 on the expression of inhibitory Smad7 protein in bronchial epithelial cells. Methods: Real-time reverse-transcriptase polymerase chain reaction was employed. Results: Stimulation with IL-10 upregulated the expression of Smad7 compared with control. Neither IL-5 nor GM-CSF induced Smad7 expression. Smad7 expression was upregulated by IL-10 plus either IL-5 or GM-CSF. IL-10 inhibited the expression of TGF-β-inducible early gene, which is known to downregulate Smad7 expression. Conclusions: Our results suggest that IL-10 acts as a regulatory cytokine in the inhibition of airway inflammation.
The Relationship in Japanese Infants between a Genetic Polymorphism in the Promoter Region of the Insulin-Like Growth Factor I Gene and the Plasma Level
Authors: Kinoshita Yumiko , Kizaki Zenro , Ishihara Yasunori , Nakajima Hisakazu , Adachi Shinsuke , Kosaka Kitaro , Kinugasa Akihiko , Sugimoto Tohru
Published: March 2007

Background: Evidence is accumulating that the promoter region of the insulin-like growth factor I (IGF-I) gene polymorphism and low levels of IGF-I are associated with type 2 diabetes, cardiovascular disease and birth weight; however, the number of wild-type alleles is different in each country. Objectives: This study aimed to examine the 737/738 marker, a cytosine–adenine repeat in the promoter region of the IGF-I gene polymorphism, and plasma IGF-I levels in Japanese infants and analyze the genetic background. Methods: Data were collected for 15 months in Kyoto Prefectural University of Medicine. The body composition parameters of all infants were determined at birth. At 5 days after birth, we took blood samples to measure the product size of the promoter region of the IGF-I gene polymorphism and plasma IGF-I. Results: In a population-based sample of 160 subjects, 6 different alleles and 16 genotypes were identified in the promoter region of the IGF-I gene polymorphism. The existence of a 196-bp allele has proved to result in a low plasma IGF-I level, a small head and chest circumference (p < 0.05) and no significant for premature birth, short-birth height and low-birth weight. Conclusions: This is the first study showing the role of the promoter region of the IGF-I gene polymorphism and the level of plasma IGF-I and body composition parameters in Japanese infants. Our results suggest genetical influence on prenatal growth and serum IGF-I levels.
An Applicability Study on a CT-Guided Stereotactic Technique for Functional Neurosurgery
Authors: Asakura T. , Uetsuhara K. , Kanemaru R. , Hirahara K.
Published: March 2007

When a CT-guided stereotactic technique for functional neurosurgery is adopted, extremely precise targeting is needed to obtain satisfactory surgical results. In this study the authors have investigated the accuracy of the target points determined by CT-guided techniques and compared with those of conventional roentgenographically controlled stereotactic procedures.Stereotactic surgery, employing the Brown-Roberts-Wells (BRW) system, was performed contemporarily 26 times in 23 patients, that is, 9 times in 8 patients for functional neurosurgery using with the roentgenographic method, and 17 times in 15 patients with the CT-guided method only for intracranial neoplasm biopsy. As a result, there were no problems of accuracy of determining the target points by CT-guided stereotactic surgery with the BRW system. When applying this technique for functional neurosurgery, it should be pointed out that there could be a discrepancy within 2 mm from the conventional target determination.
Stereotactic System and Apparatus for Use with Magnetic Resonance Imaging, Computerized Tomography, and Digital Subtraction Imaging
Authors: Olivier A. , Peters T. , Bertrand G.
Published: March 2007

A light-weight nonmagnetic, nonconductive instrument has been devised for use with magnetic resonance imaging, computerized tomography, and digital subtraction imaging for work in the field of epilepsy, brain tumors and vascular lesions. The apparatus’ main characteristic is its ability to use optionally either the lateral orthogonal or the spherical-radial approach.
Effectiveness of Radiofrequency Thermocoagulation in Recurrent Trigeminal Neuralgia after Previous Retrogasserian Rhizotomy
Authors: Kanpolat Y. , Avman N. , Gökalp H.Z. , Arasil E. , Selçuki M. , Mertol T.
Published: March 2007

Between 1974 and 1984, 428 trigeminal neuralgia cases were treated by controlled radiofrequency thermocoagulation (RFTC). 29 had recurrent trigeminal neuralgia after intracranial surgery. 26 of the 29 patients were treated by retrogasserian rhizotomy and 3 by posterior fossa exploration. Among the 26 recurrent trigeminal neuralgia following retrogasserian rhizotomy, RFTC was effective in 23 cases (88.5%), and in 3 cases (11.5%) RFTC was effective for a short period. Repeated RFTC was unable to control the pain attacks which were later relieved by posterior fossa exploration and root section. Of the 3 recurrent trigeminal neuralgia following posterior fossa exploration, RFTC was effective in 2 cases (66.6%).
Postoperative and Long-Term Results of 1,561 Stereotactic Operations in Parkinsonism
Authors: Mundinger F.
Published: March 2007

Out of a series of 3,808 (31.5.84) Parkinson operations the postoperative and long-term results of 1,561 stereotactic procedures are evaluated. The results are compared, especially in respect to the focus of therapeutic lesion (internal pallidum, oral ventral nuclei, subthalamic zona incerta and radiatio prelemniscalis). In the long range, tremor and rigidity are abolished or markedly improved in more than 80%, the associated Parkinson symptoms in between one and two thirds of cases. In the further development of the diseases the progression of the positive symptoms is blocked as well as the medically induced dyskinesia.The ability for work and better living are achieved in 60% and amelioration of the psychic situation in 30% of the cases. Operative mortality is 0.4% and morbidity is less than 2%.
Correlation of CT-Directed Target Site with Histology and Cell Culture in Cerebral Glioma
Authors: Thomas D.G.T. , Powell M.P. , Bradford R. , Darling J.L. , Olney J. , Barnard R.O.
Published: March 2007

The Brown-Roberts-Wells stereotactic system has been used to remove multiple samples from both the tumour centre and the CT-enhanced edge of intracranial tumours in 44 patients. Histological studies indicate that there is considerable variation between biopsies taken from select spatial sites within a single tumour. The tissue culture studies, using the coverslip overlay explant technique, will ultimately provide fundamental information on the biological variability of human gliomas. Although there was histological variation between multiple samples taken from a single tumour, in many cases the enhancing edge of the tumour was found to be free of infïltrating tumour cells, suggesting that radical local treatment may be warranted for tumour control.
Accuracy of CT Scans in Identifying Tumor Tissue
Authors: Hitchon P.W. , Schelper R.L. , Barloon T.
Published: March 2007

The authors present their experience with stereotactic biopsy of brain tumors. Biopsies were obtained sequentially at different depths from the center of the tumor according to coordinates derived from computerized tomography (CT). Biopsies were obtained from 23 brain tumors: 17 gliomas, 5 metastases, and 1 lymphoma. In all a total of 137 biopsies were studied from both enhancing and nonenhancing areas. The tumor yield from these biopsies was 68 and 73%, respectively. It appears that tumor tissue may be obtained from both the enhancing periphery as well as the nonenhancing center of tumors.
Intracranial Tumor Biopsy – CT-Guided Stereotactic Surgery
Authors: Poza M. , Perez-Espejo M.A. , Martinez-Lage J.F. , Esteban J.A. , Climent V. , Sola J.
Published: March 2007

A modification of Gildenberg’s technique for brain tumor biopsy is described. Marking the light beam of the gantry on the scalp with a pencil, when the lesion appears on the screen, no Scout View is necessary. With radiopaque marks on the drawn lines, the levels of the slice are transferred to a lateral conventional X-ray, for calculation of the ‘Z’ coordinate. ‘X’ and ‘Y’ coordinates are determined on the CT scanner.
A Multipurpose CT-Guided Stereotactic Instrument of Simple Design
Authors: Van Buren J.M. , Houdek P. , Ginsberg M.
Published: March 2007

The instrument is based upon a radiolucent ring fixed to the skull by four pins. This locks into a frame for CT scanning from which the x, y and z stereotactic coordinates are derived. The head ring may be locked into a compatible support on the operating table for biopsy. A similar support and localization system is used for rotational radiotherapy. With the current 14 MeV apparatus, fields as small as 2 cm in diameter are available with 90% dosage fall-off in the surrounding 1-cm shell.
Neuroanatomical Digital Image Processing in CT-Guided Stereotactic Operations
Authors: Giorgi C. , Garibotto G. , Cerchiari U. , Broggi G. , Franzini A. , Koslow M.
Published: March 2007

In order to utilize computed tomography (CT) for functional neurosurgical procedures, a number of problems must be resolved. One such problem is the development of an appropriate technique for digital processing of neuroanatomical images. Our previous work concerned a numerical reproduction of a well-kno wn stereotactic atlas and its three-dimensional manipulation. In order, to efficiently utilize this information with CT images we propose a technique for data reduction that allows the reconstruction of anatomical structures from the atlas. The logic of implementing these data in CT-assisted stereotactic surgery is described.
Spinal Cord Stimulation as a Tool f or Physiological Research
Authors: Dimitrijevic M.R. , Faganel J. , Sherwood A.M.
Published: March 2007

The use of spinal cord stimulation for alleviation of disabilities due to motor neuron lesions has provided the opportunity to explore a new approach to measurement of spinal cord physiology. Externalized leads of epidural electrodes provide the possibility of recording evoked spinal cord activity, while both externalized or implanted leads can be used to study cortical evoked responses and twitches induced by spinal cord stimulation. The use of such electrophysiological techniques can be expected to expand greatly the applicaolmy of the technique for alleviating motor disabilities, through a better definition of the degree, nature and extent of the lesion.
Disturbance in Responsiveness in Patients with Post-Meningoencephalitic Epilepsy
Authors: Rogozea R. , Florea-Ciocoiu V.
Published: March 2007

A polygraphic study of the somatic, autonomic and electroencephalographic (EEG) components of the orienting reaction elicited by an auditory stimulus was performed in 29 patients with post-meningoencephalitic epilepsy and in 116 matched subjects in three control groups. Patients with post-meningoencephalitic epilepsy had a significantly more intense orienting reaction than control subjects, the degree depending on the seizure frequency, electroclinical form and history, as well as on the features of the EEG.
Effects of Electrical Stimulation of the Human Olfactory Mucosa
Authors: Straschill Max , Stahl Henry , Gorkisch Klaus
Published: March 2007

Electrical stimulation of the human olfactory mucosa was performed by means of an electrode attached to a rhinoscope. Stimulation of the nasal mucosa did not evoke smell sensations, but suppressed smell sensations of presented odorants. When electrical stimulation followed the exposure to an odorant within a certain interval, the stimulus recalled the already faded sensation of the preceding odorant. Electrical stimulation without prior natural stimulation produced unpleasant sensations in 3 patients with a history of temporal lobe seizures and olfactory auras, but not in patients with primary, generalized or focal epilepsy.
5-Lipoxygenase–Activating Protein
Authors: Bäck Magnus , Sultan Ariane , Ovchinnikova Olga , Hansson Göran K.
Published: March 2007

Transforming growth factor-β (TGF-β) is a major antiinflammatory mediator in atherosclerosis. Transgenic ApoE
−/−
mice with a dominant-negative TGFβ type II receptor (dnTGFβRII) on CD4
+
and CD8
+
T cells display aggravated atherosclerosis. The aim of the present study was to elucidate the mechanisms involved in this enhanced inflammatory response. Gene array analyses identified the 5-lipoxygenase–activating protein (FLAP) among the most upregulated genes in both the aorta and adipose tissue of dnTGFβRII transgenic ApoE
−/−
mice compared with their ApoE
−/−
littermates, a finding that was confirmed by real-time quantitative RT-PCR. Aortas from the former mice in addition produced increased amounts of the lipoxygenase product leukotriene B
4
after ex vivo stimulation. FLAP protein expression in both the aorta and adipose tissue was detected in macrophages, but not in T cells. Four weeks of treatment with the FLAP inhibitor MK-886 (10 mg/kg in 1% tylose delivered by osmotic pumps) significantly reduced atherosclerotic lesion size and T-cell content. Finally, FLAP mRNA levels were upregulated approximately 8-fold in adipose tissue derived from obese ob/ob mice. In conclusion, the results of the present study suggest a key role for mediators of the 5-lipoxygenase pathway in inflammatory reactions of atherosclerosis and metabolic disease.
Vascular Functions of the Plasminogen Activation System
Authors: Fay William P. , Garg Nadish , Sunkar Madhavi
Published: March 2007

The plasminogen activator (PA) system, which controls the formation and activity of plasmin, plays a key role in modulating hemostasis, thrombosis, and several other biological processes. While a great deal is known about the function of the PA system, it remains a focus of intensive investigation, and the list of biological pathways and human diseases that are modulated by normal and pathologic function of its components continues to lengthen. Because of remarkable advances in molecular genetics, the laboratory mouse has become the most useful animal system to study the normal and pathologic functions of the PA system. The purpose of this review is to summarize studies that have used genetically modified mice to examine the functions of the PA system in hemostasis and thrombosis, intimal hyperplasia after vascular injury, and atherosclerosis. Particular emphasis is placed on the vascular functions of PA inhibitor-1, a key regulator of the PA system, and the multiple variables that appear to account for the complex role of PA inhibitor-1 in regulating vascular remodeling. Lastly, the strengths and limitations of using mice to model human vascular disease processes are discussed.
Hepatitis B Virus Seropositivity and the Risk of Stroke and Myocardial Infarction
Authors: Sung Joohon , Song Yun-Mi , Choi Yoon-Ho , Ebrahim Shah , Davey Smith George
Published: March 2007

Background and Purpose—

Conflicting findings on the possible association between hepatitis B virus surface antigen (HBsAg) seropositivity and atherosclerosis have been reported. We examined the association between HBsAg seropositivity and cardiovascular diseases in a cohort of Koreans with a high prevalence of hepatitis B viral infection.

Methods—

Men (N=521 421) aged 30 to 64 years were categorized into 4 groups according to HBsAg seropositivity status and the presence of liver dysfunction were followed up from 1990 to 2001 for both fatal and nonfatal myocardial infarctions (MIs) and strokes. The associations of HBsAg seropositivity with these cardiovascular diseases were examined with a Cox proportional-hazards model.

Result—

Overall, HBsAg seropositivity was associated with a decreased risk of ischemic stroke and MI and an increased risk of hemorrhagic stroke, with multivariable-adjusted hazard ratios (95% CIs) of 0.79 (0.68, 0.90), 0.74 (0.62, 0.87), and 1.33 (1.15, 1.52), respectively. Risks for stroke and MI were similar between HBsAg-seronegative and HBsAg-seropositive men in the absence of liver dysfunction, whereas men with both HBsAg seropositivity and liver dysfunction had a higher risk of hemorrhagic stroke and lower risks of ischemic stroke and MI compared with HBsAg-seronegative men.

Conclusions—

The association between HBsAg seropositivity and stroke and MI appears to be secondary to the liver dysfunction associated with hepatitis B viral infection. HBsAg seropositivity itself did not appear to play an important role in atherothrombosis through inducing a proinflammatory effect.
Systematic Review of Associations Between the Presence of Acute Ischemic Lesions on Diffusion-Weighted Imaging and Clinical Predictors of Early Stroke Risk After Transient Ischemic Attack
Authors: Redgrave Jessica N.E. , Coutts Shelagh B. , Schulz Ursula G. , Briley Dennis , Rothwell Peter M.
Published: March 2007

Background and Purpose—

Early risk of stroke after a transient ischemic attack can be reliably predicted with risk scores based on clinical features of the patient and of the ischemic event, but it is unclear how these features correlate with findings on brain imaging.

Methods—

We performed a systematic review of the literature and identified all previous studies which reported patient characteristics and the nature of transient ischemic attack symptoms in relation to appearances on diffusion-weighted imaging (DWI). We then performed a meta-analysis of the associations between the components of the risk scores and positive DWI. Authors were contacted for additional unpublished data.

Results—

Nineteen studies were identified by the systematic review, and additional unpublished data were obtained from 11 of these studies. On meta-analysis, several components of the risk scores were associated with positive DWI, including symptom duration ≥60 minutes (13 studies, odds ratio [OR], 1.50; 95% CI, 1.16 to 1.96;
P
=0.004), dysphasia (9 studies, OR, 2.25; 95% CI, 1.57 to 3.22;
P
<0.001), dysarthria (8 studies, OR, 1.73; 95% CI, 1.11 to 2.68;
P
=0.03) and motor weakness (9 studies, OR, 2.20; 95% CI, 1.56 to 3.10;
P
<0.001). However patient age, sex, hypertension and diabetes were not associated with the presence of DWI lesions. From an etiologic perspective, atrial fibrillation (9 studies, OR, 2.75; 95% CI, 1.78 to 4.25;
P
<0.001) and ipsilateral ≥50% carotid stenosis (10 studies, OR, 1.93; 95% CI, 1.34 to 2.76;
P
=0.001) were associated with positive DWI.

Conclusions—

Presence of acute ischemic lesions on DWI correlates with several clinical features known to predict stroke risk after transient ischemic attack. Large studies (sample size >1000) will therefore be required to determine the independent prognostic value of DWI and its interactions with these clinical characteristics.
Grading Scale for Prediction of Outcome in Primary Intracerebral Hemorrhages
Authors: Ruiz-Sandoval José L. , Chiquete Erwin , Romero-Vargas Samuel , Padilla-Martínez Juan J. , González-Cornejo Salvador
Published: March 2007

Background and Purpose—This study aimed to independently derive an intracerebral hemorrhage grading scale (ICH-GS) for prediction of 3 outcome measures.

Methods—We evaluated 378 patients with primary ICH at hospital arrival and during the next 30 days. Independent predictors were identified by multivariate models of in-hospital and 30-day mortality. Points were allotted to each predictor based on its prognostic performance. ICH-GS was also evaluated to predict good 30-day functional status and ICH-GS was compared with the ICH score as the reference scoring system.

Results—Independent predictors were age, Glasgow Coma Scale, ICH location, ICH volume, and intraventricular extension, all components of the ICH score. Nevertheless, different cutoffs and scoring improved substantially the prognostic power of the predictors. Compared with the ICH score, ICH-GS explained more variance in the 3 outcome measures, had higher sensitivity in predicting in-hospital and 30-day mortality, and performed equally well in predicting good functional outcome at 30 days follow up.

Conclusions—The derived ICH-GS is a simple yet robust scale in predicting in-hospital and 30-day mortality, as well as good 30-day functional status, with equivalent performance.
Understanding the Biases of Generalised Recombination: Part II
Authors: Poli Riccardo , Stephens Christopher R.
Published: March 2007

This is the second part of a two-part paper where we propose, model theoretically and study a general notion of recombination for fixed-length strings where homologous recombination, inversion, gene duplication, gene deletion, diploidy and more are just special cases. In Part I, we derived both microscopic and coarse-grained evolution equations for strings and schemata for a selecto-recombinative GA using generalised recombination, and we explained the hierarchical nature of the schema evolution equations. In this part, we provide a variety of fixed points for evolution in the case where recombination is used alone, thereby generalising Geiringer's theorem. In addition, we numerically integrate the infinite-population schema equations for some interesting problems, where selection and recombination are used together to illustrate how these operators interact. Finally, to assess by how much genetic drift can make a system deviate from the infinite-population-model predictions we discuss the results of real GA runs for the same model problems with generalised recombination, selection and finite populations of different sizes.
Training a Support Vector Machine in the Primal
Authors: Chapelle Olivier
Published: March 2007

Most literature on support vector machines (SVMs) concentrates on the dual optimization problem. In this letter, we point out that the primal problem can also be solved efficiently for both linear and nonlinear SVMs and that there is no reason for ignoring this possibility. On the contrary, from the primal point of view, new families of algorithms for large-scale SVM training can be investigated.
Exact Inferences in a Neural Implementation of a Hidden Markov Model
Authors: Beck Jeffrey M. , Pouget Alexandre
Published: March 2007

From first principles, we derive a quadratic nonlinear, first-order dynamical system capable of performing exact Bayes-Markov inferences for a wide class of biologically plausible stimulus-dependent patterns of activity while simultaneously providing an online estimate of model performance. This is accomplished by constructing a dynamical system that has solutions proportional to the probability distribution over the stimulus space, but with a constant of proportionality adjusted to provide a local estimate of the probability of the recent observations of stimulus-dependent activity-given model parameters. Next, we transform this exact equation to generate nonlinear equations for the exact evolution of log likelihood and log-likelihood ratios and show that when the input has low amplitude, linear rate models for both the likelihood and the log-likelihood functions follow naturally from these equations. We use these four explicit representations of the probability distribution to argue that, in contrast to the arguments of previous work, the dynamical system for the exact evolution of the likelihood (as opposed to the log likelihood or log-likelihood ratios) not only can be mapped onto a biologically plausible network but is also more consistent with physiological observations.
Multispike Interactions in a Stochastic Model of Spike-Timing-Dependent Plasticity
Authors: Appleby Peter A. , Elliott Terry
Published: March 2007

Recently we presented a stochastic, ensemble-based model of spike-timing-dependent plasticity. In this model, single synapses do not exhibit plasticity depending on the exact timing of pre- and postsynaptic spikes, but spike-timing-dependent plasticity emerges only at the temporal or synaptic ensemble level. We showed that such a model reproduces a variety of experimental results in a natural way, without the introduction of various, ad hoc nonlinearities characteristic of some alternative models. Our previous study was restricted to an examination, analytically, of two-spike interactions, while higher-order, multispike interactions were only briefly examined numerically. Here we derive exact, analytical results for the general n-spike interaction functions in our model. Our results form the basis for a detailed examination, performed elsewhere, of the significant differences between these functions and the implications these differences have for the presence, or otherwise, of stable, competitive dynamics in our model.
A New Backpropagation Learning Algorithm for Layered Neural Networks with Nondifferentiable Units
Authors: Oohori Takahumi , Naganuma Hidenori , Watanabe Kazuhisa
Published: March 2007

We propose a digital version of the backpropagation algorithm (DBP) for three-layered neural networks with nondifferentiable binary units. This approach feeds teacher signals to both the middle and output layers, whereas with a simple perceptron, they are given only to the output layer. The additional teacher signals enable the DBP to update the coupling weights not only between the middle and output layers but also between the input and middle layers. A neural network based on DBP learning is fast and easy to implement in hardware. Simulation results for several linearly nonseparable problems such as XOR demonstrate that the DBP performs favorably when compared to the conventional approaches. Furthermore, in large-scale networks, simulation results indicate that the DBP provides high performance.
Determination of the Horizontal Pressure Gradient Force Using Global Positioning System on board an Instrumented Aircraft
Authors: Parish Thomas R. , Burkhart Matthew D. , Rodi Alfred R.
Published: March 2007

The horizontal pressure gradient force is the single most important dynamical term in the equation of motion that governs the forcing of the atmosphere. It is well known that the slope of an isobaric surface is a measure of the horizontal pressure gradient force. Measurement of this force over mesoscale distances using an airborne platform has been attempted for over two decades in order to understand the dynamics of various wind systems. The most common technique has been to use a radar altimeter to measure the absolute height of an isobaric surface above sea level. Typical values of the horizontal pressure gradient force in the atmosphere are quite small, amounting to an isobaric surface slope of 0.0001 for a 10 m s−1 geostrophic wind at middle latitudes. Detecting the horizontal pressure gradient over irregular terrain using an instrumented aircraft has proven to be especially difficult since correction for the underlying terrain features must be made. Use of the global positioning system (GPS) is proposed here as a means to infer the horizontal pressure gradient force without the need for altimetry and terrain registration over irregular surface topography. Differential kinematic processing of data from dual-frequency, carrier phase tracking receivers on research aircraft with similar static base station receivers enables the heights of an isobaric surface to be determined with an accuracy estimated to be a few decimeters. Comparison of results obtained by conventional altimetry-based methods over the ocean and Lake Michigan with GPS reveals the potential of the GPS method at determining the horizontal pressure gradient force, even over complex terrain.
Psychopathy and the Perception of Affect and Vulnerability
Authors: Book Angela S. , Quinsey Vernon L. , Langford Dale
Published: March 2007

The relationship between psychopathic traits and the perception of nonverbal communication, including facial expressions and body language, is investigated. Participants include 59 prison inmates and 60 community members. Psychopathic traits among inmates are measured using the Psychopathy Checklist—Revised (PCL-R) and Levenson's Self Report Psychopathy Scale. Participants categorize the emotion of posed facial photographs and rate intensity of emotion. They view videotaped interactions of a confederate and a target individual and rate assertiveness using the Rathus Assertiveness Scale. There is a trend for the PCL-R to be positively correlated with the inmates' accuracy of emotional intensity ratings. Psychopathic traits are also positively associated with the accuracy of assertiveness ratings.
Expression of Bcl‐xL, Bax, and p53 in Primary Tumors and Lymph Node Metastases in Oral Squamous Cell Carcinoma
Authors: BALTAZIAK MAREK , DURAJ EWA , KODA MARIUSZ , WINCEWICZ ANDRZEJ , MUSIATOWICZ MARCIN , KANCZUGA‐KODA LUIZA , SZYMANSKA MAGDALENA , LESNIEWICZ TOMASZ , MUSIATOWICZ BOGUSLAW
Published: March 2007

Abstract:  Disturbances in expression of apoptosis‐associated proteins take part in the development and progression of many human malignancies. The aim of this study was the assessment of correlations among proteins involved in apoptosis—Bcl‐xL, Bax, and p53—as well as relationships of these proteins with selected clinicopathological features in oral squamous cell carcinoma. Consequently, we examined by immunohistochemistry, using the avidin–biotin–peroxidase method, Bcl‐xL, Bax, and p53 expression in 56 samples of primary oral squamous cell carcinoma and in 22 matched pairs of primary and metastatic tumors. The evaluation of immunostaining of Bcl‐xL, Bax, and p53 was analyzed in 10 different tumor fields, and the mean percentage of tumor cells with positive staining was evaluated. The significance of the associations was determined using Spearman correlation analysis and the chi‐square test. We found positive Bcl‐xL, Bax, and p53 immunostaining in 44.6%, 28.6%, and 58.9% of the studied primary tumors and in 63.6%, 45.5%, and 72.7% of lymph node metastases, respectively. Analysis of associations among studied proteins revealed positive correlation between Bcl‐xL and Bax in primary tumors (P < 0.03, r= 0.307). Statistically significant relationship between p53 expression in primary oral cancers and its expression in lymph node metastases (P < 0.02) as well as increased expression of Bcl‐xL, Bax, and p53 in metastatic sites compared with primary tumors could indicate an association of these proteins with oral cancer progression and development of metastases. Moreover, we suppose that knowledge about heterogeneity between primary and metastatic tumor might help to understand mechanisms of oral cancer progression.
Molecular Determinants Involved in the Increase of Damage‐Induced Apoptosis and Delay of Secondary Necrosis due to Inhibition of Mono(ADP‐Ribosyl)ation
Authors: CERELLA CLAUDIA , MEARELLI CRISTINA , AMMENDOLA SERGIO , DE NICOLA MILENA , D'ALESSIO MARIA , MAGRINI ANDREA , BERGAMASCHI ANTONIO , GHIBELLI LINA
Published: March 2007

Abstract:  ADP‐ribosylations are reversible posttranslational modifications that regulate the activity of target proteins, catalyzed by two different classes of enzymes, namely poly(ADP‐ribosyl)polymerases (PARPs) and mono(ADP‐ribosyl)transferases (ADPRTs). It is now emerging that ADP‐ribosylation reactions control signal transduction pathways, mostly as a response to cell damage, aimed at both cell repair and apoptosis. Inhibition of ADPRTs, but not PARPs, increases the extent of apoptosis induced by cytocidal treatments, at the same time delaying secondary necrosis, the process leading to plasma membrane collapse in apoptotic cells, and responsible for apoptosis‐related inflammation in vivo. Thus, ADPRT inhibitors may be ideal as adjuvants to cytocidal therapies; to this purpose, we investigated the molecular determinant(s) for such effects by probing a set of molecules with similar structures. We found that the apoptosis‐modulating effects were mimicked by those compounds possessing an amidic group in the same position as two of the most popular ADPRT inhibitors, namely, 3‐aminobenzamide and nicotinamide. This study may provide useful suggestions in designing molecules with therapeutic potential to be used as adjuvant in cytocidal therapies.