bluuebunny/crossref_metadata_2025 huggingface dataset:
ON THE TAXONOMY OF FLATTENED MOEBIUS STRIPS
Authors: AVRIN J. S.
Published: May 2011

The taxonomy of flattened Moebius strips (FMS) is reexamined in order to systematize the basis for its development. An FMS is broadly characterized by its twist and its direction of traverse. All values of twist can be realized by combining elementary FMS configurations in a process called fusion but the result is degenerate; a multiplicity of configurations can exist with the same value of twist. The development of degeneracy is discussed in terms of several structural factors and two principles, conservation of twist and continuity of traverse. The principles implicate a corresponding pair of constructs, a process of symbolic convolution, and the inner product of symbolic vectors. Combining constructs and structural factors leads to a systematically developed taxonomy in terms of twist categories assembled from permutation groups. Taxonomical structure is also graphically revealed by the geometry of an expository edifice that validates the convolution process while displaying the products of fusion. A formulation that combines some of the algebraic precepts of Quantum Mechanics with the primitive combinatorics and degeneracies inherent to the FMS genus is developed. The potential for further investigation and application is also discussed. An appendix outlines the planar extension of the fusion concept and another summarizes a related application of convolution.
KNOTS WITH DISTINCT PRIMITIVE/PRIMITIVE AND PRIMITIVE/SEIFERT REPRESENTATIVES
Authors: GUNTEL BRANDY J.
Published: May 2011

Berge introduced knots that are primitive/primitive with respect to the genus 2 Heegaard surface, F, in S3; surgery on such knots at the surface slope yields a lens space. Later Dean described a similar class of knots that are primitive/Seifert with respect to F; surgery on these knots at the surface slope yields a Seifert fibered space. Here we construct a two-parameter family of knots that have distinct primitive/Seifert embeddings in F with the same surface slope, as well as a family of torus knots that have a primitive/primitive representative and a primitive/Seifert representative with the same surface slope.
LINKS AND SPINES
Authors: KODA YUYA
Published: May 2011

We define two kinds of invariants of links in closed 3-manifolds, the s-complexity(s ∈ ℕ) and the block number, by considering decompositions of links in closed orientable 3-manifolds by spines. The first one is a generalization of the complexity of links defined by Pervova and Petronio. After providing properties of these invariants, we construct special spines of strongly-cyclic coverings branched over generalized twist knots in lens spaces, including S3and ℝP3, which provide upper bounds for the invariants.
GENERALIZATION BOUNDS OF REGULARIZATION ALGORITHMS DERIVED SIMULTANEOUSLY THROUGH HYPOTHESIS SPACE COMPLEXITY, ALGORITHMIC STABILITY AND DATA QUALITY
Authors: CHANG XIANGYU , XU ZONGBEN , ZOU BIN , ZHANG HAI
Published: May 2011

A main issue in machine learning research is to analyze the generalization performance of a learning machine. Most classical results on the generalization performance of regularization algorithms are derived merely with the complexity of hypothesis space or the stability property of a learning algorithm. However, in practical applications, the performance of a learning algorithm is not actually affected only by an unitary factor just like the complexity of hypothesis space, stability of the algorithm and data quality. Therefore, in this paper, we develop a framework of evaluating the generalization performance of regularization algorithms combinatively in terms of hypothesis space complexity, algorithmic stability and data quality. We establish new bounds on the learning rate of regularization algorithms based on the measure of uniform stability and empirical covering number for general type of loss functions. As applications of the generic results, we evaluate the learning rates of support vector machines and regularization networks, and propose a new strategy for regularization parameter setting.
CONVERGENCE OF THE CONTINUOUS WAVELET TRANSFORMS ON THE ENTIRE LEBESGUE SET OF Lp-FUNCTIONS
Authors: ASHUROV RAVSHAN
Published: May 2011

The almost everywhere convergence of wavelets transforms of Lp-functions under minimal conditions on wavelets is well known. But this result does not provide any information about the exceptional set (of Lebesgue measure zero), where convergence does not hold. In this paper, under slightly stronger conditions on wavelets, we prove convergence of wavelet transforms everywhere on the entire Lebesgue set of Lp-functions. On the other hand, practically all the wavelets, including Haar and "French hat" wavelets, used frequently in applications, satisfy our conditions. We also prove that the same conditions on wavelets guarantee the Riemann localization principle in L1 for the wavelet transforms.
Hypoxic preconditioning enhances bone marrow mesenchymal stem cell migration via Kv2.1 channel and FAK activation
Authors: Hu Xinyang , Wei Ling , Taylor Tammi M. , Wei Jianfeng , Zhou Xin , Wang Jian-An , Ping Yu Shan
Published: May 2011

Transplantation using stem cells including bone marrow mesenchymal stem cells (BMSCs) is emerging as a potential regenerative therapy after ischemic attacks in the heart and brain. The migration capability of transplanted cells is a critical cellular function for tissue repair. Based on our recent observations that hypoxic preconditioning (HP) has multiple benefits in improving stem cell therapy and that the potassium Kv2.1 channel acts as a promoter for focal adhesion kinase (FAK) activation and cell motility, the present investigation tested the hypothesis that HP treatment can increase BMSC migration via the mechanism of increased Kv2.1 expression and FAK activities. BMSCs derived from green fluorescent protein-transgenic mice were treated under either normoxic (N-BMSC) or hypoxic (0.5% O2) (HP-BMSC) conditions for 24 h. Western blot analysis showed HP selectively upregulated Kv2.1 expression while leaving other K+ channels, such as Kv1.5 and Kv1.4, unaffected. Compared with normoxic controls, significantly larger outward delayed rectifier K+ currents were recorded in HP-BMSCs. HP enhanced BMSC migration/homing activities in vitro and after intravenous transplantation into rats subjected to permanent myocardial infarction (MI). The HP-promoted BMSC migration was inhibited by either blocking K+ channels or knocking down Kv2.1. Supporting a relationship among HP, Kv2.1, and FAK activation, HP increased phosphorylation of FAK397 and FAK576/577, and this effect was antagonized by blocking K+ channels. These findings provide novel evidence that HP enhances the ability of BMSCs to migrate and home to the injured region; this effect is mediated through a regulatory role of Kv2.1 on FAK phosphorylation/activation.
Enhancement of in vitro human tubulogenesis by endothelial cell-derived factors: implications for in vivo tubular regeneration after injury
Authors: Miya Masaaki , Maeshima Akito , Mishima Keiichiro , Sakurai Noriyuki , Ikeuchi Hidekazu , Kuroiwa Takashi , Hiromura Keiju , Yokoo Hideaki , Nojima Yoshihisa
Published: May 2011

Renal proximal tubular epithelium can regenerate after various insults. To examine whether the tubular repair process is regulated by surrounding peritubular capillaries, we established an in vitro human tubulogenesis model that mimics in vivo tubular regeneration after injury. In this model, HGF, a potent renotropic factor, dose dependently induced tubular structures in human renal proximal tubular epithelial cells cultured in gels. Consistent with regenerating tubular cells after injury, HGF-induced tubular structures expressed a developmental gene, Pax-2, and a mesenchymal marker, vimentin, and formed a lumen with aquaporin-1 expression. Electron microscopic analysis showed the presence of microvilli on the apical site of the lumen, suggesting that these structures are morphologically equivalent to renal tubules in vivo. When cocultured with human umbilical vein endothelial cells (HUVEC), HGF-induced tubular formation was significantly enhanced. This could not be reproduced by the addition of VEGF, basic FGF, or PDGF. Protein array revealed that HUVEC produced various matrix metalloproteinases (MMPs). The stimulatory effects of coculture with HUVEC or HUVEC-derived conditional medium were almost completely abolished by addition of the tissue inhibitor of metalloproteinase (TIMP)-1 or TIMP-2. These data suggest that endothelial cell-derived factors including MMPs play a critical role in tubulogenesis and imply a potential role of peritubular capillary endothelium as a source of factor(s) required for tubular recovery after injury.
A mutual information analysis of neural coding of speech by low-frequency MEG phase information
Authors: Cogan Gregory B. , Poeppel David
Published: May 2011

Recent work has implicated low-frequency (<20 Hz) neuronal phase information as important for both auditory (<10 Hz) and speech [theta (∼4–8 Hz)] perception. Activity on the timescale of theta corresponds linguistically to the average length of a syllable, suggesting that information within this range has consequences for segmentation of meaningful units of speech. Longer timescales that correspond to lower frequencies [delta (1–3 Hz)] also reflect important linguistic features—prosodic/suprasegmental—but it is unknown whether the patterns of activity in this range are similar to theta. We investigate low-frequency activity with magnetoencephalography (MEG) and mutual information (MI), an analysis that has not yet been applied to noninvasive electrophysiological recordings. We find that during speech perception each frequency subband examined [delta (1–3 Hz), thetalow (3–5 Hz), thetahigh (5–7 Hz)] processes independent information from the speech stream. This contrasts with hypotheses that either delta and theta reflect their corresponding linguistic levels of analysis or each band is part of a single holistic onset response that tracks global acoustic transitions in the speech stream. Single-trial template-based classifier results further validate this finding: information from each subband can be used to classify individual sentences, and classifier results that utilize the combination of frequency bands provide better results than single bands alone. Our results suggest that during speech perception low-frequency phase of the MEG signal corresponds to neither abstract linguistic units nor holistic evoked potentials but rather tracks different aspects of the input signal. This study also validates a new method of analysis for noninvasive electrophysiological recordings that can be used to formally characterize information content of neural responses and interactions between these responses. Furthermore, it bridges results from different levels of neurophysiological study: small-scale multiunit recordings and local field potentials and macroscopic magneto/electrophysiological noninvasive recordings.
Contribution of motoneuron intrinsic properties to fictive motor pattern generation
Authors: Wright Terrence M. , Calabrese Ronald L.
Published: May 2011

Previously, we reported a canonical ensemble model of the heart motoneurons that underlie heartbeat in the medicinal leech. The model motoneurons contained a minimal set of electrical intrinsic properties and received a synaptic input pattern based on measurements performed in the living system. Although the model captured the synchronous and peristaltic motor patterns observed in the living system, it did not match quantitatively the motor output observed. Because the model motoneurons had minimal intrinsic electrical properties, the mismatch between model and living system suggests a role for additional intrinsic properties in generating the motor pattern. We used the dynamic clamp to test this hypothesis. We introduced the same segmental input pattern used in the model to motoneurons isolated pharmacologically from their endogenous input in the living system. We show that, although the segmental input pattern determines the segmental phasing differences observed in motoneurons, the intrinsic properties of the motoneurons play an important role in determining their phasing, particularly when receiving the synchronous input pattern. We then used trapezoidal input waveforms to show that the intrinsic properties present in the living system promote phase advances compared with our model motoneurons. Electrical coupling between heart motoneurons also plays a role in shaping motoneuron output by synchronizing the activity of the motoneurons within a segment. These experiments provide a direct assessment of how motoneuron intrinsic properties interact with their premotor pattern of synaptic drive to produce rhythmic output.
NMDA-induced burst firing in a model subthalamic nucleus neuron
Authors: Kubota Shigeru , Rubin Jonathan E.
Published: May 2011

Experiments in rat brain slice show that hyperpolarized subthalamic nucleus (STN) neurons engage in slow, regular burst firing when treated with an N-methyl-d-aspartate (NMDA) bath. A depolarization-activated inward current (DIC) has been hypothesized to contribute to this bursting activity. To explore the mechanism for STN burst firing in this setting, we augmented a previously published conductance-based computational model for single rat STN neurons to include both DIC and NMDA currents, fit to data from published electrophysiological recordings. Simulations show that with these additions, the model engages in bursting activity at <1 Hz in response to hyperpolarizing current injection and that this bursting exhibits several features observed experimentally in STN. Furthermore, a reduced model is used to show that the combination of NMDA and DIC currents, but not either alone, suffices to generate oscillations under hyperpolarizing current injection. STN neurons show enhanced burstiness in Parkinson's disease patients and experimental models of parkinsonism, and the burst mechanism studied presently could contribute to this effect.
Finding Minimum Norm Fixed Point of Nonexpansive Mappings and Applications
Authors: Yang Xue , Liou Yeong-Cheng , Yao Yonghong
Published: May 2011

We construct two new methods for finding the minimum norm fixed point of nonexpansive mappings in Hilbert spaces. Some applications are also included.
Iron Deficiency Anemia in Adult Onset Still's Disease with a Serum Ferritin of 26,387 μg/L
Authors: Patel Sheetal , Monemian Seyed , Khalid Ayesha , Dosik Harvey
Published: May 2011

Serum ferritin rises in the anemia of chronic inflammation reflecting increased iron storage and other changes mediated by inflammation. When iron deficiency coexists, the ferritin may not always decline into the subnormal range. We describe the rare interaction of iron deficiency with the extreme hyperferritinemia characteristic of adult onset Still's disease. The combination has clinical relevance and allows deductions about the presence of serum ferritin at 26,387 μg/L despite obvious iron depletion. The diagnosis of iron deficiency anemia was delayed and became fully obvious when her Still's disease remitted and serum ferritin decreased to 6.5 μg/L. The coexistence of iron deficiency should be considered when evaluating a patient with anemia of chronic inflammation even when the ferritin level is elevated several hundredfold. Further insights on ferritin metabolism in Still's disease are suggested by the likelihood that the patient's massive hyperferritinemia in the acute phase of Still's disease was almost entirely of the iron-free apoferritin form.
Activity of Antimicrobial Peptides and Conventional Antibiotics against Superantigen PositiveStaphylococcus aureusIsolated from the Patients with Neoplastic and Inflammatory Erythrodermia
Authors: Baranska-Rybak Wioletta , Cirioni Oscar , Dawgul Malgorzata , Sokolowska-Wojdylo Malgorzata , Naumiuk Lukasz , Szczerkowska-Dobosz Aneta , Nowicki Roman , Roszkiewicz Jadwiga , Kamysz Wojciech
Published: May 2011

Superantigens are proteins comprising a group of molecules produced by various microorganisms. They are involved in pathogenesis of several human diseases. The aim of the study was the comparison of susceptibility to antibiotics and antimicrobial peptides (AMPs) ofStaphylococcus aureus(SA) strains producing staphylococcal enterotoxins SEA, SEB, SEC, SED, and TSST-1 and nonproducing ones. In the group of the total 28 of the patients with erythrodermia the presence of SA was confirmed in 24 cases. The total of 14 strains of SA excreted enterotoxins SEA, SEC, SED, and TSST-1. We did not observe that strains producing mentioned superantigens were less susceptible to AMPs (aurein 1.2, citropin 1.1, lipopeptide, protegrin 1, tachyplesin 3, temporin A, and uperin 3.6). The opposite situation was observed in conventional antibiotics. SA strains excreting tested superantigens had higher MICs and MBCs than nonproducing ones. The interesting finding considering the high efficacy of AMPs, against all examined strains of SA, makes them attractive candidates for therapeutic implication.
Delay‐Dependent Stability Analysis and Synthesis for Uncertain Impulsive Switched System with Mixed Delays
Authors: Du Binbin , Zhang Xiaojie
Published: May 2011

This paper studies the asymptotic stability problem for a class of uncertain
impulsive switched systems with discrete and distributed delays. Based on Lyapunov
functional theory, delay‐dependent sufficient LMI conditions are established for the asymptotic
stability of the considered systems. Moreover, an appropriate feedback controller is constructed for stabilizing the corresponding closed‐loop system. The results are illustrated to be efficient through an example.
Inward Leakage in Tight-Fitting PAPRs
Authors: Koh Frank C. , Johnson Arthur T. , Rehak Timothy E.
Published: May 2011

A combination of local flow measurement techniques and fog flow visualization was used to determine the inward leakage for two tight-fitting powered air-purifying respirators (PAPRs), the 3M Breathe-Easy PAPR and the SE 400 breathing demand PAPR. The PAPRs were mounted on a breathing machine head form, and flows were measured from the blower and into the breathing machine. Both respirators leaked a little at the beginning of inhalation, probably through their exhalation valves. In both cases, the leakage was not enough for fog to appear at the mouth of the head form.
Regulation and Function of Syk Tyrosine Kinase in Mast Cell Signaling and Beyond
Authors: de Castro Rodrigo Orlandini
Published: May 2011

The protein tyrosine kinase Syk plays a critical role in FcεRI signaling in mast cells. Binding of Syk to phosphorylated immunoreceptor tyrosine-based activation motifs (p-ITAM) of the receptor subunits results in conformational changes and tyrosine phosphorylation at multiple sites that leads to activation of Syk. The phosphorylated tyrosines throughout the molecule play an important role in the regulation of Syk-mediated signaling. Reconstitution of receptor-mediated signaling in Syk-/-cells by wild-type Syk or mutants which have substitution of these tyrosines with phenylalanine together within vitroassays has been useful strategies to understand the regulation and function of Syk.
Static Scheduling of Periodic Hardware Tasks with Precedence and Deadline Constraints on Reconfigurable Hardware Devices
Authors: Belaid Ikbel , Muller Fabrice , Benjemaa Maher
Published: May 2011

Task graph scheduling for reconfigurable hardware devices can be defined as finding a schedule for a set of periodic tasks with precedence, dependence, and deadline constraints as well as their optimal allocations on the available heterogeneous hardware resources. This paper proposes a new methodology comprising three main stages. Using these three main stages, dynamic partial reconfiguration and mixed integer programming, pipelined scheduling and efficient placement are achieved and enable parallel computing of the task graph on the reconfigurable devices by optimizing placement/scheduling quality. Experiments on an application of heterogeneous hardware tasks demonstrate an improvement of resource utilization of 12.45% of the available reconfigurable resources corresponding to a resource gain of 17.3% compared to a static design. The configuration overhead is reduced to 2% of the total running time. Due to pipelined scheduling, the task graph spanning is minimized by 4% compared to sequential execution of the graph.
Preparation of a Nanoscaled Poly(vinyl alcohol)/Hydroxyapatite/DNA Complex Using High Hydrostatic Pressure Technology for In Vitro and In Vivo Gene Delivery
Authors: Kimura Tsuyoshi , Nibe Yoichi , Funamoto Seiichi , Okada Masahiro , Furuzono Tsutomu , Ono Tsutomu , Yoshizawa Hidekazu , Fujisato Toshiya , Nam Kwangwoo , Kishida Akio
Published: May 2011

Our previous research showed that poly(vinyl alcohol) (PVA) nanoparticles incorporating DNA with hydrogen bonds obtained by high hydrostatic pressurization are able to deliver DNA without any significant cytotoxicity. To enhance transfection efficiency of PVA/DNA nanoparticles, we describe a novel method to prepare PVA/DNA nanoparticles encapsulating nanoscaled hydroxyapatites (HAps) prepared by high hydrostatic pressurization (980 MPa), which is designed to facilitate endosomal escape induced by dissolving HAps in an endosome. Scanning electron microscopic observation and dynamic light scattering measurement revealed that HAps were significantly encapsulated in PVA/HAp/DNA nanoparticles. The cytotoxicity, cellular uptake, and transgene expression of PVA/HAp/DNA nanoparticles were investigated using COS-7 cells. It was found that, in contrast to PVA/DNA nanoparticles, their internalization and transgene expression increased without cytotoxicity occurring. Furthermore, a similar level of transgene expression between plasmid DNA and PVA/HAp/DNA nanoparticles was achieved using in vivo hydrodynamic injection. Our results show a novel method of preparing PVA/DNA nanoparticles encapsulating HAp nano-crystals by using high hydrostatic pressure technology and the potential use of HAps as an enhancer of the transfection efficiency of PVA/DNA nanoparticles without significant cytotoxicity.
A General Composite Algorithms for Solving General Equilibrium Problems and Fixed Point Problems in Hilbert Spaces
Authors: Wangkeeree Rattanaporn , Kamraksa Uthai , Wangkeeree Rabian
Published: May 2011

We introduce a
general composite algorithm for finding a common
element of the set of solutions of a general equilibrium
problem and the common fixed point set of a finite family of
asymptotically nonexpansive mappings in the framework of Hilbert
spaces. Strong convergence of such iterative scheme is obtained
which solving some variational inequalities for a strongly
monotone and strictly pseudocontractive mapping. Our results
extend the corresponding recent results of Yao and Liou (2010).
EGFR Signaling Regulates Tumor Cell Migration in Craniopharyngiomas
Authors: Hölsken Annett , Gebhardt Matthias , Buchfelder Michael , Fahlbusch Rudolf , Blümcke Ingmar , Buslei Rolf
Published: May 2011

Purpose: Constitutive Wnt signaling caused by mutations in the β-catenin gene is a molecular hallmark of adamantinomatous craniopharyngiomas (adaCP) and promotes infiltration into adjacent brain tissue. Herein, we studied the pathogenic role of epidermal growth factor receptor (EGFR) activation in adaCP and whether tumor cell migration can be inhibited by the tyrosine kinase inhibitor gefitinib.

Experimental Design: EGFR expression and activation [phosphorylated EGFR (EGFR-P)] was examined in a cohort of 25 surgical adaCP samples by PCR and Western blotting. Regional and cellular localization patterns of EGFR-P, β-catenin, and its target gene product Fascin were determined by immunofluorescence microscopy. Mutation analysis and gene copy number assay were carried out to examine genetic alterations in the EGFR gene. The impact of EGFR signaling on tumor cell migration was studied in vitro by using 11 primary human adaCP cultures treated with the EGFR ligand EGF and its inhibitor gefitinib.

Results: Neither mutations nor amplifications in the EGFR gene were detected in our adaCP series. However, EGFR-P was detectable in tumor cell clusters located at the brain infiltration border and colocalized with nuclear β-catenin and Fascin. Activated EGFR significantly promoted tumor cell migration in vitro, whereas gefitinib reduced both tumor cell motility and Fascin expression.

Conclusion: Our data suggest EGFR signaling to play a role in cell migration and brain infiltration of adaCP. Targeting the EGFR signaling pathway by gefitinib may present a promising pharmacologic option in the treatment of this challenging tumor disease. Clin Cancer Res; 17(13); 4367–77. ©2011 AACR.
Incremental Diagnostic Value and Impact on Patient Management of Somatostatin Receptor Scintigraphy with Indium-111-Pentetreotide in Gastroenteropancreatic Neuroendocrine Tumors
Authors: Usmani Sharjeel , Khan Haider Ali , Abdulla Maha , Ahmed Najeeb , abu Huda Fawaz , Marafi Fahad , al Kandari Farida , al Mohannadi Shihab , al Nafisi Naheel
Published: May 2011

Objective: To evaluate the efficacy of somatostatin analog scintigraphy with indium-111-pentetreotide and its overall impact on management in patients with gastroenteropancreatic neuroendocrine tumors (GEP-NET). Subjects and Methods: Twenty-two consecutive patients with a proven or clinically suspected GEP-NET with or without proven metastases were imaged at 24 and 48 h after injection of 111In-pentetreotide. The scintigraphic findings were compared with results from conventional imaging methods. The final diagnosis was based on histopathological and surgical findings and complementary radiology. Results: Somatostatin receptor-positive lesions were found in 20 of the patients, whereas conventional methods were positive in 18 patients. Additionally, 13 new tumor sites were discovered by somatostatin receptor scintigraphy in 5 patients (liver: 6; chest: 2; bone: 1; abdomen: 4). The surgical therapeutic strategy was changed in 7 patients (32%). Conclusions: Our data reinforced that scintigraphy with 111In-pentetreotide represents the imaging modality of choice in the initial evaluation of GEP-NET. It is highly accurate and can identify clinically unsuspected lesions and optimize the overall staging. It also guides optimal therapy choice and most importantly identifies patients with inoperable or metastatic disease who might be candidates for high-dose targeted therapy.
Thrombin-Activatable Fibrinolysis Inhibitor in Breast Cancer Patients
Authors: Kaftan O. , Kasapoglu B. , Koroglu M. , Kosar A. , Yalcin S.K.
Published: May 2011

Objective: To evaluate the levels of thrombin-activatable fibrinolysis inhibitor (TAFI) activity and also its relationship with other homeostasis markers in breast cancer patients. Subjects and Methods: Forty-two female patients with breast cancer and 24 healthy women (controls) were enrolled in the study and fasting blood samples of all cases were drawn from a large antecubital vein for assay of TAFI and other homeostasis tests. Results: The TAFI levels were 79.5 ± 15.5 and 39.3 ± 12.1 in patients and controls, respectively, and the difference was statistically significant (p < 0.001). In the patient group, the serum fibrinogen level was 504.9 ± 224.8, while in the control group it was 393.9 ± 100.5, and the difference was also statistically significant (p < 0.001). Conclusion: The data showed that increased levels of TAFI are a contributing factor of thrombotic disorders in breast cancer patients.
Risk Indicators of Postoperative Complications following Surgical Extraction of Lower Third Molars
Authors: Malkawi Ziad , Al-Omiri Mahmoud K. , Khraisat Ameen
Published: May 2011

Objective: The aim of this prospective clinical trial was to evaluate the incidence of postoperative complications following surgical extraction of lower third molars (L8) and the risk factors and clinical variables associated with these complications. Subjects and Methods: Three-hundred and twenty-seven consecutive patients (128 men and 199 women, mean age = 23.1 ± 3.9 years, range: 18–40) were recruited to this study. The L8 of all the patients were surgically extracted. Immediate and late complications like pain, swelling, trismus, paresthesia, bleeding, dry socket, infection and fracture were assessed 3 and 7–14 days, respectively, following the surgery. Results: The most frequent immediate and late complications were slight pain, swelling, and trismus. Thirty-nine (11.9%) patients reported dry socket and 10 (0.3%) reversible sensory nerve complications. More immediate and late complications were experienced by females (p = 0.000 and 0.016, respectively). Older subjects reported more late complications. Frequent immediate and late complications were associated with preexisting pericoronitis, longer duration of operation, extraction of two molars, flaps with vertical incision, extractions with bone removal, extractions without tooth sectioning and distoangular impactions (p ≤ 0.05). Linear regression analysis showed that the above factors were able to predict postoperative complications. Conclusion: The most frequent immediate and late complications were slight pain, swelling, and trismus. Preoperative complaints, angulation of the impacted molars, duration of surgery, type of surgical flap, the need for bone removal and tooth sectioning could predict and had an impact on the incidence of postoperative complications following L8 removal. Females and older patients were likely to have more postoperative complications following surgical extraction of L8.
Mild Prenatal Stress-Modulated Behavior and Neuronal Spine Density without Affecting Amphetamine Sensitization
Authors: Muhammad Arif , Kolb Bryan
Published: May 2011

The present study investigated the effect of prenatal stress (PS) on juvenile behavior and adult amphetamine (AMPH) sensitization, as well as the effect of the interaction between experience (i.e. PS) and drug (i.e. AMPH) on cortical thickness and neuronal morphology in corticolimbic regions in rats. Juvenile male and female rats, exposed to gestational stress, were tested in behavioral tasks that included open field locomotion, elevated plus maze, novel object recognition, and play fighting behavior. The development and persistence of drug-induced behavioral sensitization in adults were tested by chronic AMPH administration and challenge, respectively. Spine density in corticolimbic regions was examined for structural plasticity. The findings showed that PS produced anxiety-like behavior in males. Furthermore, PS in males resulted in female-like play and enhanced partial rotation defense, whereas in females PS increased the probability of evasion in response to an attack. AMPH administration resulted in gradual increase in behavioral sensitization that persisted at least for 2 weeks; however, PS did not influence AMPH-induced behavioral sensitization in either male or female rats. Moreover, PS increased the spine density in the nucleus accumbens (NAc) and decreased it in the medial prefrontal cortex (mPFC) without any alteration in the orbital frontal cortex (OFC). Similarly, AMPH administration increased spine density in the NAc and mPFC, whereas a decrease was observed in the OFC. However, PS prevented the drug-induced alterations in the spine density observed in controls. In sum, PS modulated juvenile behavior and altered brain morphology without influencing AMPH-induced behavioral sensitization substantially.
Mixed Adenocarcinoma-Carcinoid (Collision Tumor) of the Appendix
Authors: Singh Naorem Gopendro , Mannan Abul Ala Syed Rifat , Kahvic Mirza , Nur Ali Mohamd
Published: May 2011

Objective: To report a case of mixed adenocarcinoma and carcinoid in the gastrointestinal tract. Clinical Presentation and Intervention: A 52-year-old man presented with a mass at the base of the appendix. On microscopic examination of the tumor, mixed adenocarcinoma and carcinoid was identified. The carcinoid component was insular/trabecular in morphology, and the epithelial component revealed mucinous adenocarcinoma. Morphologically and immunohistochemically the 2 components showed a clear-cut distinction, without any intervening intermediate cell population. The adenocarcinomatous component displayed omental deposit and metastasis to the regional lymph nodes. One year later, the patient developed multiple metastatic deposits of adenocarcinoma in the liver, rectus muscle, ileum and sigmoid colon. Conclusion: This tumor had an aggressive clinical course and behaved more like adenocarcinoma than carcinoid.
Severe Presentation of Necrotizing Ulcerative Periodontitis in a Nigerian HIV-Positive Patient: A Case Report
Authors: Umeizudike Kehinde Adesola , Savage Kofoworola Olaide , Ayanbadejo Patricia Omowunmi , Akanmu Sulaimon Akanni
Published: May 2011

Objective: To report a case of severe necrotizing ulcerative periodontitis (NUP) with a rarely associated sequestrum formation in a Nigerian HIV-positive patient. Clinical Presentation and Intervention: A 47-year-old HIV-positive male patient with no history of previous dental visits presented with a severe toothache in his lower jaw of 4 weeks’ duration, which had affected his ability to chew properly. Clinical examination revealed marked gingival inflammation, moderate gingival recession and mobility of some of his lower anterior teeth: 31, 32, and 33. There was also a sequestrum present associated with the affected teeth. His CD4 cell count was 226 cells/mm3. His viral load was very high (360,082 copies/ml). The intervention included thorough debridement of the necrotic lesion and sequestrectomy. The patient responded well to treatment after 1 week of follow-up. Unfortunately, the CD4 count was not assessed further because the patient was lost to follow-up. Conclusion: This case showed that a high CD4 cell count does not necessarily prevent the occurrence of NUP in HIV-positive patients. Intervention might have enhanced a rapid positive response to the treatment within a short time.
Linguistic Validation of the Chronic Respiratory Disease Questionnaire in an Arabic-Speaking Population with Chronic Respiratory Diseases
Authors: Al-Ghimlas Fahad , Al-Omran Mohammed , Guyatt Gordon H.
Published: May 2011

Objective: To develop an Arabic version of the Chronic Respiratory Disease Questionnaire (CRQ) to be known as ArabiCRQ. Materials and Methods: We conducted a linguistic validation of the CRQ in the Arabic language. The validation process involved 4 phases, including forward and backward translations, pilot testing, and revision to produce a final version of the ArabiCRQ. Five native Arabic-speaking patients with chronic obstructive pulmonary disease completed the ArabiCRQ both in initial and follow-up visits. Wording was modified according to feedback the participants provided. Results: Two of the patients’ scores changed appreciably, despite ensuring their clinical stability. Conclusion: The ArabiCRQ may be a valuable tool to assess the health-related quality of life in patients with chronic respiratory diseases.
Dimebon Does Not Ameliorate Pathological Changes Caused by Expression of Truncated (1–120) Human Alpha-Synuclein in Dopaminergic Neurons of Transgenic Mice
Authors: Shelkovnikova Tatyana A. , Ustyugov Alexey A. , Millership Steven , Peters Owen , Anichtchik Oleg , Spillantini Maria Grazia , Buchman Vladimir L. , Bachurin Sergey O. , Ninkina Natalia N.
Published: May 2011

Background: Recent clinical studies have demonstrated that dimebon, a drug originally designed and used as a non-selective antihistamine, ameliorates symptoms and delays progress of mild to moderate forms of Alzheimer’s and Huntington’s diseases. Although the mechanism of dimebon action on pathological processes in degenerating brain is elusive, results of studies carried out in cell cultures and animal models suggested that this drug might affect the process of pathological accumulation and aggregation of various proteins involved in the pathogenesis of proteinopathies. However, the effect of this drug on the pathology caused by overexpression and aggregation of alpha-synuclein, including Parkinson’s disease (PD), has not been assessed. Objective:To test if dimebon affected alpha-synuclein-induced pathology using a transgenic animal model. Methods: We studied the effects of chronic dimebon treatment on transgenic mice expressing the C-terminally truncated (1–120) form of human alpha-synuclein in dopaminergic neurons, a mouse model that recapitulates several biochemical, histopathological and behavioral characteristics of the early stage of PD. Results: Dimebon did not improve balance and coordination of aging transgenic animals or increase the level of striatal dopamine, nor did it prevent accumulation of alpha-synuclein in cell bodies of dopaminergic neurons. Conclusion: Our observations suggest that in the studied model of alpha-synucleinopathy dimebon has very limited effect on certain pathological alterations typical of PD and related diseases.
Influence of Different Professional Prophylactic Methods on Fluorescence Measurements for Detection of Occlusal Caries
Authors: Diniz M.B. , Sciasci P. , Rodrigues J.A. , Lussi A. , Cordeiro R.C.L.
Published: May 2011

This study aimed to evaluate the influence of professional prophylactic methods on the DIAGNOdent 2095, DIAGNOdent 2190 and VistaProof performance in detecting occlusal caries. Assessments were performed in 110 permanent teeth at baseline and after bicarbonate jet or prophylactic paste and rinsing. Performance in terms of sensitivity improved after rinsing of the occlusal surfaces when the prophylactic paste was used. However, the sodium bicarbonate jet did not significantly influence the performance of the fluorescence-based methods. It can be concluded that different professional prophylactic methods can significantly influence the performance of fluorescence-based methods for occlusal caries detection.
A Phytosterolemia Patient Presenting Exclusively with Macrothrombocytopenia and Stomatocytic Hemolysis
Authors: Wang Gaifeng , Wang Zhaoyue , Liang Jianying , Cao Lijuan , Bai Xia , Ruan Changgeng
Published: May 2011

Background: Phytosterolemia is a rare autosomal recessive lipid storage disease. It is caused by mutations of ABCG5 and ABCG8 genes and characterized by the increased plasma levels of plant sterols. The common clinical manifestations include tendon and tuberous xanthomas and premature coronary heart disease; it has occasionally been associated with hematologic abnormalities. Aims: We report a phytosterolemia patient presenting exclusively with macrothrombocytopenia and stomatocytic hemolysis and discuss its clinical significance. Case Report: The patient, aged 31 years, was born of a consanguineous marriage. He had epistaxis from childhood and underwent splenectomy because of thrombocytopenia, anemia and splenomegaly at the age of 9 years. His blood film showed prominent stomatocytes and macroplatelets. High performance liquid chromatography showed a grossly elevated level of phytosterols in the blood. The patient was confirmed to be a homozygote of missense mutation R419H in ABCG5. Conclusion: We describe a phytosterolemia patient whose clinical manifestations were macrothrombocytopenia, stomatocytic hemolysis and splenomegaly, without the common features of this disorder. Our results suggest that blood cells could be a target for the toxic effect of plasma plant sterols, which should be measured in patients with unexplained stomatocytosis and/or macrothrombocytopenia in order to determine if they have phytosterolemia.
Knock-Out of β-Glucosidase 2 Has No Influence on Dextran Sulfate Sodium-Induced Colitis
Authors: Scharl Michael , Leucht Katharina , Frey-Wagner Isabelle , Zeitz Jonas , Hausmann Martin , Fischbeck Anne , Liebisch Gerhard , Kellermeier Silvia , Pesch Theresa , Arikkat Joba , Schmitz Gerd , Fried Michael , Yildiz Yildiz , Rogler Gerhard
Published: May 2011

Background/Aims: The non-lysosomal glucosylceramidase, β-glucosidase (Gba2), hydrolyzes glucosylceramide to glucose and ceramide (Cer). Cer is a potent second-messenger lipid that plays an important role in signaling cascades involved in apoptosis. The aim of this study was to investigate whether Gba2 knock-out (Gba2–/–) affects the extent of dextran sulfate sodium (DSS)-induced colitis in mice. Methods: Acute colitis was induced in wild-type (WT) and Gba2–/– mice by administration of 2% DSS in drinking water. After 7 days, mice underwent colonoscopy and were sacrificed. Results: Both DSS-treated WT (n = 10) and Gba2–/– (n = 12) mice showed elevated histological and endoscopic scores compared to respective H2O controls (n = 9 each). However, no significant differences between the DSS groups were detected. Flow cytometric analysis of propidium iodide staining, cleavage of caspases-3 and -8, indicative for apoptosis, as well as Cer levels were not altered in DSS-treated WT or Gba2–/– mice. Gba2–/– resulted in slightly decreased expression of glucocerebrosidase (Gba1) as well as in upregulation of proteins being involved in cellular regeneration, such as STAT3 (signal transducer and activator of transcription), JNK and iNOS, upon DSS treatment. Conclusion: We demonstrate that Gba2–/– does not affect the extent of DSS-induced inflammation in mice, however, it might be involved in tissue regeneration in response to toxic agents.
The Genomic Architecture of Sporadic Heart Failure
Authors: Dorn Gerald W.
Published: May 2011

Common or sporadic systolic heart failure (heart failure) is the clinical syndrome of insufficient forward cardiac output resulting from myocardial disease. Most heart failure is the consequence of ischemic or idiopathic cardiomyopathy. There is a clear familial predisposition to heart failure, with a genetic component estimated to confer between 20% and 30% of overall risk. The multifactorial etiology of this syndrome has complicated identification of its genetic underpinnings. Until recently, almost all genetic studies of heart failure were designed and deployed according to the common disease–common variant hypothesis, in which individual risk alleles impart a small positive or negative effect and overall genetic risk is the cumulative impact of all functional genetic variations. Early studies used a candidate gene approach focused mainly on factors within adrenergic and renin-angiotensin pathways that affect heart failure progression and are targeted by standard pharmacotherapeutics. Many of these reported allelic associations with heart failure have not been replicated. However, the preponderance of data supports risk-modifier effects for the Arg389Gly polymorphism of β1-adrenergic receptors and the intron 16 in/del polymorphism of angiotensin-converting enzyme. Recent unbiased studies using genome-wide single nucleotide polymorphism microarrays have shown fewer positive results than when these platforms were applied to hypertension, myocardial infarction, or diabetes, possibly reflecting the complex etiology of heart failure. A new cardiovascular gene-centric subgenome single nucleotide polymorphism array identified a common heat failure risk allele at 1p36 in multiple independent cohorts, but the biological mechanism for this association is still uncertain. It is likely that common gene polymorphisms account for only a fraction of individual genetic heart failure risk, and future studies using deep resequencing are likely to identify rare gene variants with larger biological effects.
Some Regions within Broca's Area Do Respond More Strongly to Sentences than to Linguistically Degraded Stimuli: A Comment on Rogalsky and Hickok ()
Authors: Fedorenko Evelina , Kanwisher Nancy
Published: May 2011

On the basis of their review of the literature, Rogalsky and Hickok [Rogalsky, C., & Hickok, G. The role of Broca's area in sentence comprehension. Journal of Cognitive Neuroscience, 23, 1664–1680, 2011] conclude that there is currently no strong evidence for the existence of “sentence-specific processing regions within Broca's area” (p. 1664). Their argument is based, in part, on the observation that many previous studies have failed to detect an effect in the left inferior frontal regions for contrasts between sentences and linguistically degraded control conditions (e.g., lists of unconnected words, lists of nonwords, or acoustically degraded sentence stimuli). Our data largely replicate this lack of activation in inferior frontal regions when traditional random-effects group analyses are conducted but crucially show robust activations in the same data for the same contrasts in almost every subject individually. Thus, it is the use of group analyses in studies of language processing, not the idea that sentences robustly activate frontal regions, that needs to be reconsidered. This reconsideration has important methodological and theoretical implications.
Dopamine and the Management of Attentional Resources: Genetic Markers of Striatal D2 Dopamine Predict Individual Differences in the Attentional Blink
Authors: Colzato Lorenza S. , Slagter Heleen A. , de Rover Mischa , Hommel Bernhard
Published: May 2011

The attentional blink (AB)—a deficit in reporting the second of two target stimuli presented in close succession in a rapid sequence of distracters—has been related to processing limitations in working memory. Given that dopamine (DA) plays a crucial role working memory, the present study tested whether individual differences in the size of the AB can be predicted by differences in genetic predisposition related to the efficiency of dopaminergic pathways. Polymorphisms related to mesocortical and nigrostriatal dopaminergic pathways were considered, as well as polymorphisms related to norepinephrine (NE), a transmitter system that has also been suspected to play a role in the AB. In a sample of 157 healthy adults, we studied the dependency of the individual magnitude of the AB and the C957T polymorphism at the DRD2 gene (associated with striatal DA/D2 receptors), the DARPP32 polymorphism (associated with striatal DA/D1), the COMT Val158Met polymorphism (associated with frontal DA), DBH444 g/a and DBH5′-ins/del polymorphisms (polymorphisms strongly correlated with DA beta hydroxylase, the enzyme catalyzing the DA–NE conversion) and NET T-182C (a polymorphism related to the NE transporter). DRD2 C957T T/T homozygotes showed a significantly smaller AB, whereas polymorphisms associated with frontal DA and NE were unrelated to performance. This outcome pattern suggests a crucial role of the nigrostriatal dopaminergic pathway and of nigrostriatal D2 receptors, in particular, in the management of attentional resources.
On the Wave Spectrum Generated by Tropical Heating
Authors: Ortland David A. , Alexander M. Joan , Grimsdell Alison W.
Published: May 2011

Convective heating profiles are computed from one month of rainfall rate and cloud-top height measurements using global Tropical Rainfall Measuring Mission and infrared cloud-top products. Estimates of the tropical wave response to this heating and the mean flow forcing by the waves are calculated using linear and nonlinear models. With a spectral resolution up to zonal wavenumber 80 and frequency up to 4 cpd, the model produces 50%–70% of the zonal wind acceleration required to drive a quasi-biennial oscillation (QBO). The sensitivity of the wave spectrum to the assumed shape of the heating profile, to the mean wind and temperature structure of the tropical troposphere, and to the type of model used is also examined. The redness of the heating spectrum implies that the heating strongly projects onto Hough modes with small equivalent depth. Nonlinear models produce wave flux significantly smaller than linear models due to what appear to be dynamical processes that limit the wave amplitude. Both nonlinearity and mean winds in the lower stratosphere are effective in reducing the Rossby wave response to heating relative to the response in a linear model for a mean state at rest.