bluuebunny/crossref_metadata_2025 huggingface dataset:
Induction of human neutrophil chemotaxis by Candida albicans-derived β-1,6-long glycoside side-chain-branched β-glucan
Authors: Sato Tadashi , Iwabuchi Kazuhisa , Nagaoka Isao , Adachi Yoshiyuki , Ohno Naohito , Tamura Hiroshi , Seyama Kuniaki , Fukuchi Yoshinosuke , Nakayama Hitoshi , Yoshizaki Fumiko , Takamori Kenji , Ogawa Hideoki
Published: May 2006

Polysaccharide β-1,3-D-glucans (β-glucans) are components of the cell wall of various fungi and show immunomodulatory activities. β-Glucans have been reported to enhance neutrophil accumulation during pathogenic fungi-induced lung inflammation. Therefore, we examined whether β-glucans themselves possess chemotactic activities for human neutrophils. Among several kinds of β-glucans, β-1,6-long glucosyl side-chain-branched β-glucan, isolated from Candida albicans [Candida soluble β-D-glucan (CSBG)], dose-dependently induced neutrophil migration in a Boyden chamber system. In contrast, 1,6-monoglucosyl-branched β-glucans, such as Sparassis crispa-derived β-glucan (SCG) and grifolan (GRN), which were derived from nonpathogenic fungi, hardly induced neutrophil migration. Moreover, CSBG-induced neutrophil migration was inhibited completely by liposomes containing neutral glycosphingolipid lactosylceramide (LacCer; Galβ1-4Glc-ceramide) but not NeuAcα2-3Galβ1-4Glcβ1-1′-Cer ganglioside. Furthermore, binding experiments demonstrated that CSBG bound to glycosphingolipids (such as LacCer) with a terminal galactose residue; however, SCG and GRN (1,6-monoglucosyl-branched β-glucans) did not bind to LacCer. It is important that a Src kinase inhibitor protein phosphatase 1, a phosphatidylinositol-3 kinase (PI-3K) inhibitor wortmannin, and a Gαi/o inhibitor pertussis toxin inhibited neutrophil migration toward CSBG. Taken together, our results suggest that β-1,6-long glucosyl side-chain-branched β-glucan CSBG binds to LacCer and induces neutrophil migration through the activation of Src family kinase/PI-3K/heterotrimeric G-protein signal transduction pathways.
Effects of glucocorticoids on STAT4 activation in human T cells are stimulus-dependent
Authors: Fahey Angela J , Robins R Adrian , Kindle Karin B , Heery David M , Constantinescu Cris S
Published: May 2006

Glucocorticoids affect the immune system by a number of mechanisms, including modulation of cytokine production in lymphocytes. Glucocorticoids suppress T helper cell type 1 immune responses by decreasing the ability of T cells to respond to interleukin (IL)-12, a major inducer of interferon (IFN)-γ. IFN-β increases the expression of the anti-inflammatory cytokine IL-10 and suppresses IL-12. Signaling pathways through IFN-β and the IL-12 receptor (IL-12R) involve activation by phosphorylation of signal transducer and activator of transcription 4 (STAT4). Our aim was to investigate the effects of dexamethasone on STAT4 activation by IFN-β and IL-12 in human T cell blasts. We report that dexamethasone decreases IL-12-induced STAT4 phosphorylation and IFN-γ production and enhances IFN-β-induced STAT4 activation and IL-10 production. These effects are associated with a down-regulation of IL-12Rβ1 expression but an up-regulation of IFN-βR. These results indicate that the effect of glucocorticoids on the STAT4 signaling pathway depends on the stimulus activating that pathway.
Nitric oxide-dependent killing of Cryptococcus neoformans by B-1-derived mononuclear phagocyte
Authors: Ghosn Eliver Eid Bou , Russo Montchilo , Almeida Sandro Rogerio
Published: May 2006

The role of B lymphocytes in protecting the host against pulmonary Cryptococcus neoformans infection is until now, uncertain. A recent study using B lymphocyte-deficient mice suggests that B lymphocytes play a protective role in cryptococcal infection. It has been well established that at least three B cell subsets, B-1a, B-1b, and B-2, are present in the mouse periphery. B-1 cells constitute a minor fraction of the B cell population in the spleen and are not detected in lymph nodes of mice. We demonstrated that B-1 cells migrate to a nonspecific, inflammatory focus and differentiate into macrophage-like cells. However, the role these cells might play on the kinetics and evolution of the inflammatory response and on fungal infection has not yet been established. Based on these data, we decided to investigate the interaction of B-1-derived mononuclear phagocytes (BDMP) with C. neoformans to elucidate the possible influence of this cell in the progression of the disease. In this study, we demonstrated that the BDMP cell internalized C. neoformans and that this process was mediated by complement receptor 3. Thus, our results showed that the BDMP cell was more fungicidal than a macrophage and up-regulated major histocompatibility complex type II and the CD86 costimulatory molecule with the production of proinflammatory cytokines. The phagocytosis of C. neoformans results in the nitric oxide (NO)-mediated death of the fungus, as demonstrated by experiments using NO synthase 2 knockout and aminoguanidine-treated, wild-type mice.
The Relationship between Libido and Testosterone Levels in Aging Men
Authors: Travison Thomas G. , Morley John E. , Araujo Andre B. , O’Donnell Amy B. , McKinlay John B.
Published: May 2006

Context: Although it is known that serum testosterone (T) concentrations are related to libido, the strength of that relationship in community-dwelling men has not yet been determined.

Objective: Our objective was to assess the strength and significance of the association between aging men’s self-reports of libido and serum T concentrations.

Design: Our study was a community-based evaluation of men’s health and aging, including three data collection waves: baseline (T1, 1987–1989) and follow-ups (T2, 1995–1997; T3, 2002–2004). Libido was measured on a 14-point scale assessing self-reported frequency of desire and thoughts/fantasies; low libido was defined as a score of less than 7 of 14.

Setting: We conducted an epidemiological study in greater Boston, Massachusetts.

Participants: There were 1632 men aged 40–70 yr at baseline, with follow-up on 922 (56%) at 9 yr (T2) and 623 (38%) at 15 yr (T3).

Main Outcome Measures: We assessed total and calculated bioavailable T .

Results: Three hundred eighteen (19%) subjects reported low libido at baseline. Libido and T displayed a significant association. However, the difference in mean T levels between those subjects with low libido and those without was small; analyses indicated a 3.4 ng/dl (0.12 nmol/liter) increase in total T per unit increase in libido. Subjects reporting low libido exhibited an increased but modest probability of exhibiting low T. Dividing T concentrations by the number of androgen receptor gene cytosine, adenine, guanine repeats did not enhance associations.

Conclusions: Libido and T concentrations are strongly related at the population level. However, the value of individual patient reports of reduced libido as indicators of low T levels is open to question.
Reduction of Aldehyde with Tributyltin Hydride-HMPA Combined System
Authors: Shibata Ikuya , Yoshida Tomoyuki , Baba Akio , Matsuda Haruo
Published: May 2006

Bu3SnH–HMPA combined system is an efficient reagent for the reduction of aldehydes. The reaction proceeds in good yields, and chemoselective carbonyl reduction is achieved for the substrate which includes another reducible group. Moreover, the intermediate, tin alkoxide, undergoes further reaction such as the preparation of ethers and heterocyclic compounds in the one pot procedure.
Zirconocene–Alkene Complexes. An X-Ray Structure and a Novel Preparative Method
Authors: Takahashi Tamotsu , Murakami Masato , Kunishige Masaki , Saburi Masahiko , Uchida Yasuzo , Kozawa Kozo , Uchida Tokiko , Swanson Douglas R , Negishi Ei-ichi
Published: May 2006

Structural determination of the first zirconocene–olefin complex, i.e., Cp2Zr(PhCH=CHPh)(PMe3), by X-ray crystallography is presented. Zirconium–olefin complexes such as ethylene and butene complexes can be selectively prepared in high yields from dialkylzirconocenes. On treatment of Cp2Zr(CH3)(PhCH2CH2) with, PMe3 a styrene complex 5 was obtained in good yield.
Regioisomeric 6A,6X,6Y-Tri-O-sulfonylated β-Cyclodextrin
Authors: Fujita Kahee , Tahara Tsutomu , Koga Toshitaka
Published: May 2006

All of five regioisomeric 6A ,6X ,6Y-tri-O-(p-toluenesulfonyl)-β-cyclodextrins were prepared, isolated, and their structures were determined through a combination of the extended Körner method, 3,6-anhydration, and the Taka amylase A-catalyzed hydrolysis.
How Many Monte Carlo Simulations Does One Need to Do?
Authors: Lerche Ian , Mudford Brett S.
Published: May 2006

This article derives an estimation procedure to evaluate how many Monte Carlo realizations need to be done in order to achieve prescribed accuracies in the estimated mean value and also in the cumulative probabilities of achieving values greater than, or less than, a particular value as the chosen particular value is allowed to vary. In addition, by inverting the argument and asking what the accuracies are that result for a prescribed number of Monte Carlo realizations, one can assess the computer time that would be involved should one choose to carry out the Monte Carlo realizations. These two complementary procedures are of great benefit in attempting to control the worth of undertaking an unknown number of Monte Carlo realizations, and of continuing to carry out the unknown number until the results have reached a level of accuracy that one deems acceptable. Such a procedure is not only computer intensive; however, is also very open-ended, a less than desirable trait when running a complex computer program that might take many hours or days to run through even once. The procedure presented here allows one to assess, ahead of performing a large number of Monte Carlo realizations, roughly how many are actually needed. Several illustrative numerical examples provide indications how one uses this novel procedure in practical situations.
Comparison of the Geochemical Characteristics of “Barkinite” and other Macerals from the Dahe Mine, South China
Authors: Sun Yuzhuang , Horsfield B.
Published: May 2006

Late Permian coal samples from the Dale Mine, South China, were separated into macerai groups in order to compare the characteristics of “barkinite” with vitrinite, inertinite, and sporinite. The maceral groups were extracted and analysed by GC-MS. The extract residues (kerogen) were analysed by open-system pyrolysis. The results indicate that “barkinite” has geochemical characteristics different from those of vitrinite, inertinite, and sporinite. The significant differences lie in the compound contents obtained by open-system pyrolysis method. The contents of saturated and aromatic compounds from the “barkinite” sample are also different from the vitrinite, inertinite, and sporinite samples, but these differences are observed only in their compound quantities.
In-Service Analytical Investigation of Precast-Concrete, Short-Span, Skewed Bridges with Integral Abutment Walls
Authors: Farhey Daniel N. , Zoghi Manoochehr
Published: May 2006

Precast-concrete, skewed bridges with integral abutment walls are typically designed as simplified two-dimensional rigid portal frames, neglecting the degrading effects of the skew angle and laterally unsymmetrical vertical loading. This practice produces under-designed bridges for certain aspect ratios, causing cracking and local deterioration near the obtuse corners of the deck. To evaluate the limitations of this practice, an analytical study was carried out for the live load response at the linear service level. Three-dimensional finite-element models of precast-concrete, short-span, skewed bridges with integral abutment walls were developed and analyzed. For some bridge configurations, both the positive and negative moment stresses are higher than the stresses given by simplified two-dimensional frame analysis. In other cases, the two-dimensional frame method results in over-designed bridges. The results were presented in correlation diagrams, enabling simple comparison and quantification. The correlation diagrams also provide modification factors to amend the simplified two-dimensional frame design.
Study of a New Macro-Finite Element Model for Seismic Performance of RC Shear Walls Using Quasi-Static Experiments
Authors: Li Hong-Han , Li Bing
Published: May 2006

Quasi-static tests are described of nine reinforced concrete (R/C) shear walls under cyclic lateral loading. The relationship between force and displacement is obtained to verify the macro-finite element model for R/C shear wall presented. The corresponding formulations for this model are given. By comparing the failure process and behaviour of the wall specimens under different axial compression ratios (the axial compression ratio is equal to the vertical load divided by the product of the concrete design compressive strength and the section area) and shear-span ratios, with the analyses of test and hysteretic curves, it can be concluded that with the increase of axial compression ratio to some extent, the bearing capacity of the shear wall will increase if the shear-span ratio of shear walls is the same, but the ductility of the walls will decrease and that degradations of strength and stiffness are also more serious. At the same time, the failure behaviour of shear walls will be changed from shear failure to bending failure with the enhancement of shear-span ratio, the bearing-load capacity will decrease and the ductility and energy absorption characteristics of shear walls will be strengthened.
A New Method for System Fatigue Reliability Analysis of Offshore Steel Jacket
Authors: Wang Yuanqing , Shi Yongjiu , Wang Chunguang , Li Shaofu
Published: May 2006

Fatigue Failure is a common failure mode for offshore steel jacket and the system fatigue reliability analysis for this type of structure has been developed greatly in recent year. Nevertheless none of those methods gives satisfactory results and there are some problems such as long calculating time, low accuracy, etc. To deal with these problems, a Synthesis Searching Method (SSM) and corresponding program for the system fatigue reliability analysis of structure system is proposed in this paper which can identify the dominant fatigue failure paths of the structures more efficiently and much faster. The analytical probability of system failure through these paths has been evaluated. A numerical example is given to illustrate the efficiency of the proposed method. It is demonstrated that this method has great advantage in analyzing the fatigue reliability of large and complex offshore steel jackets.
Aerodynamic Coefficients of Inclined Circular Cylinders with Artificial Rivulet in Smooth Flow
Authors: Xu Y. L. , Li Y. L. , Shum K. M. , Kwok K. C. F. , Kwok K. C. S. , Hitchcock P. A.
Published: May 2006

A series of wind tunnel tests were carried out to measure drag and lift coefficients of inclined circular cylinders with artificial rivulet for later investigation on wind-rain-induced cable vibration. The axial flow effect was naturally included in the tests, compared with previous non-yawed horizontal cylinder tests. The test Reynolds number for smooth circular cylinders in uniform flow ranged from 9.38 × 104 to 1.93 × 105. A special test apparatus was designed and manufactured for easy execution of measurements. The effects of artificial rivulet, its shape, and its size on aerodynamic coefficients are discussed in this paper based on wind tunnel test results. The influence of wind yaw angle, wind speed, and cable diameter is also estimated. Furthermore, the possible transformation of wind tunnel test results to the cylinders of different inclinations and yaw angles from those used in the tests is explored.
Failure Criteria for Grouted Concrete Block Masonry under Biaxial Compression
Authors: Liu Lipeng , Tang Daixin , Zhai Ximei
Published: May 2006

Grouted concrete block masonry (GCBM) exhibits distinct directional properties. By the phenomenological approach, totally 86 tests on 3 kinds of macro-element were conducted for different principal stress ratios under plane stress, and 4 standard specimens were tested in shear. The anisotropic failure criteria are obtained in terms of normalized principal stress space. Comparisons of failure curves for 3 kinds of macro-element are made and it is found that the biaxial compressive strength when the applied stress direction and the material axis coincide is much greater than when the applied stress is inclined to the material axis. By the failure criteria and coordinate transformation, the law relating strength to orientation is obtained. It shows that the degree of anisotropy is affected by the difference of applied stresses. It behaves strongly only when one principal stress predominates and gradually becomes weak as the difference between the two principal compressive stresses decreases. The masonry seems to be isotropic in equal biaxial compression. The work conducted in this paper provides a basis for further theoretical study of the behavior of GCBM under biaxial stress.
Dapped-End Strengthening of Full-Scale Prestressed Double Tee Beams with FRP Composites
Authors: Huang Pei-Chang , Nanni Antonio
Published: May 2006

The unusual shape of the dapped-end beam develops a severe stress concentration at the re-entrant corner. If suitable reinforcement is not provided close to the re-entrant corner, the diagonal tension crack may grow rapidly and failure may occur with little or no warning. This paper reports the testing of three full-scale prestressed concrete (PC) double tee beams (five tests) in shear at the re-entrant corner. One dapped-end of each beam was reinforced with internal steel reinforcement as a bench mark and the other was strengthened with externally bonded carbon fiber reinforced polymer (CFRP) laminates. Of the two CFRP strengthened dapped-ends one used one-ply externally bonded CFRP reinforcement and the other two-ply externally bonded CFRP reinforcement with a U-anchor. The tests revealed that the reinforcement arrangements have significant influence on the member response. For one of the CFRP cases, the application of the anchor was such that failure by fiber rupture rather than peeling was achieved. Results from design computations were confirmed.
Structural Assessment of Rapid Deployment Canopy Structure
Authors: Elsheikh Ahmed , Gengnagel Christoph
Published: May 2006

A lightweight, deployable canopy system has been designed to provide weather protection for events seating. Built as a cantilever truss fixed to the back of seating systems, the canopy avoids the use of columns within the viewing area and is deployed from the ground level. A full-scale prototype has been tested to demonstrate its fulfilment of its functional requirements. Current research looks at methods to optimise the structural performance of the system to make it more reliable and efficient. The points considered include the use of curved and continuous members in the compression chord, the making of tension chord and diagonal bracing members from cables and the optimisation of the cantilever geometry. The potential use of straight and non-continuous compression chord members is discussed. The importance of controlling the geometry of the structure and how it can lead to more desirable internal force distributions is also studied. This work will help guide the ongoing development of the new system to make it both more reliable and more cost effective.
Quality Assessment of Published Health Economic Analyses from South America
Authors: Machado Márcio , Iskedjian Michael , Einarson Thomas R
Published: May 2006

Background:

Health economic analyses have become important to healthcare systems worldwide. No studies have previously examined South America's contribution in this area.

Objective:

To survey the literature with the purpose of reviewing, quantifying, and assessing the quality of published South American health economic analyses.

Methods:

A search of MEDLINE (1990–December 2004), EMBASE (1990–December 2004), International Pharmaceutical Abstracts (1990–December 2004), Literatura Latino-Americana e do Caribe em Ciências da Saûde (1982–December 2004), and Sistema de Informacion Esencial en Terapéutica y Salud (1980–December 2004) was completed using the key words cost-effectiveness analysis (CEA), cost-utility analysis (CUA), cost-minimization analysis (CMA), and cost-benefit analysis (CBA); abbreviations CEA, CUA, CMA, and CBA; and all South American country names. Papers were categorized by type and country by 2 independent reviewers. Quality was assessed using a 12 item checklist, characterizing scores as 4 (good), 3 (acceptable), 2 (poor), 1 (unable to judge), and 0 (unacceptable). To be included in our investigation, studies needed to have simultaneously examined costs and outcomes.

Results:

We retrieved 25 articles; one duplicate article was rejected, leaving 24 (CEA = 15, CBA = 6, CMA = 3; Brazil = 9, Argentina = 5, Colombia = 3, Chile = 2, Ecuador = 2, 1 each from Peru, Uruguay, Venezuela). Variability between raters was less than 0.5 point on overall scores (OS) and less than 1 point on all individual items. Mean OS was 2.6 (SD 1.0, range 1.4–3.8). CBAs scored highest (OS 2.8, SD 0.8), CEAs next (OS 2.7, SD 0.7), and CMAs lowest (OS 2.0, SD 0.5). When scored by type of question, definition of study aim scored highest (OS 3.0, SD 0.8), while ethical issues scored lowest (OS 1.5, SD 0.9). By country, Peru scored highest (mean OS 3.8) and Uruguay had the lowest scores (mean OS 2.2). A nonsignificant time trend was noted for OS (R2 = 0.12; p = 0.104).

Conclusions:

Quality scores of health economic analyses articles published in South America were rated poor to acceptable and lower than previous research from other countries. Thus, efforts are needed to improve the reporting quality of these analyses in South America. Future research should examine the region's level of expertise and educational opportunities for those in the field of health economics.
Intranuclear Coccidiosis in Tortoises: Nine Cases
Authors: Garner M. M. , Gardiner C. H. , Wellehan J. F. X. , Johnson A. J. , McNamara T. , Linn M. , Terrell S. P. , Childress A. , Jacobson E. R.
Published: May 2006

Chelonian intranuclear coccidiosis has been reported once, in two radiated tortoises ( Geochelone radiata), and is apparently rare. We describe intranuclear coccidiosis diagnosed histologically in two radiated tortoises, three Travancore tortoises ( Indotestudo forstenii), two leopard tortoises ( Geochelone pardalis), one bowsprit tortoise ( Chersina angulata), and one impressed tortoise ( Manouria impressa). Infection was systemic and involved alimentary, urogenital, respiratory, lymphoid, endocrine, and integumentary systems. Trophozoites, meronts, merozoites, macrogametocytes, microgametocytes, and nonsporulated oocysts were seen histologically or by electron microscopy. intracytoplasmic and extracellular stages of parasite development also were identified histologically. Sequencing of a coccidial 18S rRNA consensus polymerase chain reaction (PCR) product revealed a novel sequence that provided phylogenetic information and may be useful for further diagnostic test design. intranuclear coccidiosis was associated with variable degrees of inflammation in all cases, was considered the cause of death in six tortoises, and was a substantial contributing factor to the cause of death in two tortoises.
Carcinoma ex Pleomorphic Adenoma with Sebaceous Differentiation in the Mandibular Salivary Gland of a Dog
Authors: Smrkovski O. A. , LeBlanc A. K. , Smith S. H. , LeBlanc C. J. , Adams W. H. , Tobias K. M.
Published: May 2006

A carcinoma ex pleomorphic adenoma was diagnosed in the left mandibular salivary gland of an 8-year-old female spayed dog. The animal presented with a large nonpainful swelling in the left submandibular region. A computed tomography scan detected an irregularly enhancing soft tissue mass that was closely associated with the left external ear canal and extended to the left wing of the atlas. On surgical exploration, the mass was intimately associated with the left mandibular salivary gland. Both the mass and the adjacent gland were removed, and the diagnosis was determined by histopathology. The tumor was comprised of basaloid and low columnar epithelial cells, many glandular units formed by well-differentiated sebocytes, and multifocal regions of necrosis, mineralization, and hemorrhage. Salivary gland tumors with sebaceous differentiation are very rare in animals, with one previously reported case in a cat.
Dramaturgy, humor, and criticism: How Goffman reveals Seinfeld's critique of American culture
Authors: Paolucci Paul , Richardson Margaret
Published: May 2006

Both Goffman's dramaturgical paradigm and the humor of the television program
Book reviews
Authors: Morreall John , Bucaria Chiara , Attardo Salvatore
Published: May 2006

Mikita Brottman:

Rachel Giora:
Estrogen Receptors α and β Differentially Regulate the Transcriptional Activity of the Urocortin Gene
Authors: Haeger Paola , Andrés María Estela , Forray María Inés , Daza Claudia , Araneda Silvia , Gysling Katia
Published: May 2006

Urocortin (Ucn), a highly conserved metazoan gene, is related to stress and feeding, behaviors with significant gender differences. We investigated whether estrogens regulate the expression of the Ucn gene using transient transfection in PC12 cells with the human Ucn (hUcn) promoter coupled to luciferase and either α or β estrogen receptors (ERα or ERβ, respectively). The results demonstrate that estradiol (E2) increases the activity of the hUcn promoter via ERα, and decreases hUcn promoter activity through ERβ. Deletions of the hUcn promoter show that the increase in promoter activity mediated by E2-ERα depends on a promoter region containing a half-estrogen response element and an Sp1 site, and the decrease mediated by E2-ERβ depends on a proximal promoter region containing a cAMP response element. Ucn and ERs coexist in neurons of rat hypothalamic nuclei, giving anatomical support for a direct effect of estrogen receptors on the Ucn gene. Byin situhybridization, we observed that cycling female rats have a higher number of cells expressing Ucn mRNA than males in the paraventricular nucleus of the hypothalamus (PVN) and the septum. Both of these brain nuclei are related to stress behaviors and express moderate levels of Ucn. Furthermore, Ucn mRNA was significantly decreased in the PVN and increased in the septum 30 d after ovariectomy. Acute E2administration to ovariectomized rats significantly increased Ucn mRNA expression in the PVN and septum. In conclusion, ourin vitroandin vivoevidence suggests that estrogens exert a direct and differential transcriptional regulation of the Ucn gene.
Two Brain Sites for Cannabinoid Reward
Authors: Zangen Abraham , Solinas Marcello , Ikemoto Satoshi , Goldberg Steven R. , Wise Roy A.
Published: May 2006

The recent findings thatΔ9tetrahydrocannabinol (Δ9THC), the active agent in marijuana and hashish, (1) is self-administered intravenously, (2) potentiates the rewarding effects of electrical brain stimulation, and (3) can establish conditioned place preferences in laboratory animals, suggest that these drugs activate biologically primitive brain reward mechanisms. Here, we identify two chemical trigger zones for stimulant and rewarding actions ofΔ9THC. Microinjections ofΔ9THC into the posterior ventral tegmental area (VTA) or into the shell of the nucleus accumbens (NAS) increased locomotion, and rats learned to lever-press for injections ofΔ9THC into each of these regions. Substitution of vehicle for drug or treatment with a cannabinoid CB1receptor antagonist caused response cessation. Microinjections ofΔ9THC into the posterior VTA and into the posterior shell of NAS established conditioned place preferences. Injections into the core of the NAS, the anterior VTA, or dorsal to the VTA were ineffective. These findings link the sites of rewarding action ofΔ9THC to brain regions where such drugs as amphetamines, cocaine, heroin, and nicotine are also thought to have their sites of rewarding action.
Antibodies against the NG2 Proteoglycan Promote the Regeneration of Sensory Axons within the Dorsal Columns of the Spinal Cord
Authors: Tan Andrew M. , Colletti Mario , Rorai Ann T. , Skene J. H. Pate , Levine Joel M.
Published: May 2006

The NG2 chondroitin sulfate proteoglycan inhibits axon growthin vitro. Levels of NG2 increase rapidly in the glial scars that form at sites of CNS injury, suggesting that NG2 may inhibit axon regeneration. To determine the functions of NG2, we infused mixtures of neutralizing or non-neutralizing anti-NG2 monoclonal antibodies into the dorsally transected adult rat spinal cord and analyzed the regeneration of ascending mechanosensory axons anatomically. At 1 week after injury, ascending sensory axons in control animals terminated caudal to the lesion within an area containing dense deposits of NG2 immunoreactivity. In animals treated with the neutralizing anti-NG2 antibodies, labeled axons penetrated the caudal border of the lesion and grew into and beyond the lesion center. The low intrinsic growth capacity of adult neurons may also limit the ability of damaged axons to regenerate. To enhance growth, we combined antibody treatment with a peripheral nerve conditioning lesion. After a conditioning lesion and treatment with control, non-neutralizing antibodies, many sensory axons grew into the lesion core. These axons did not grow past the rostral border of the lesion; rather, they grew along the dorsal surface of the spinal cord and within any remaining pieces of the dorsal roots. In contrast, combining a peripheral nerve conditioning lesion with neutralizing anti-NG2 antibodies resulted in sensory axon regeneration past the glial scar and into the white matter rostral to the injury site. The combinatorial approach used here that neutralizes extrinsic inhibition and increases intrinsic growth results in anatomically correct axon regeneration, a prerequisite for functional recovery.
Distinct Physiological Mechanisms Underlie Altered Glycinergic Synaptic Transmission in the Murine Mutantsspastic,spasmodic, andoscillator
Authors: Graham Brett A. , Schofield Peter R. , Sah Pankaj , Margrie Troy W. , Callister Robert J.
Published: May 2006

Spastic(spa),spasmodic(spd), andoscillator(ot) mice have naturally occurring glycine receptor (GlyR) mutations, which manifest as motor deficits and an exaggerated “startle response.” Using whole-cell recording in hypoglossal motoneurons, we compared the physiological mechanisms by which each mutation alters GlyR function. Mean glycinergic miniature IPSC (mIPSC) amplitude and frequency were dramatically reduced (>50%) compared with controls for each mutant. mIPSC decay times were unchanged inspa/spa(4.5 ± 0.3 vs 4.7 ± 0.2 ms), reduced inspd/spd(2.7 ± 0.2 vs 4.7 ± 0.2 ms), and increased inot/ot(12.3 ± 1.2 vs 4.8 ± 0.2 ms). Thus, inspastic, GlyRs are functionally normal but reduced in number, whereas inspasmodic, GlyR kinetics is faster. Theoscillatormutation results in complete absence of α1-containing GlyRs; however, some non-α1-containing GlyRs persist at synapses. Fluctuation analysis of membrane current, induced by glycine application to outside-out patches, showed that mean single-channel conductance was increased inspa/spa(64.2 ± 4.9 vs 36.1 ± 1.4 pS), but unchanged inspd/spd(32.4 ± 2.1 vs 35.3 ± 2.1 pS). GlyR-mediated whole-cell currents inspa/spaexhibited increased picrotoxin sensitivity (27 vs 71% block for 100 μm), indicating α1 homomeric GlyR expression. The picrotoxin sensitivity of evoked glycinergic IPSCs and conductance of synaptic GlyRs, as determined by nonstationary variance analysis, were identical forspa/spaand controls. Together, these findings show the three mutations disrupt GlyR-mediated inhibition via different physiological mechanisms, and thespasticmutation results in “compensatory” α1 homomeric GlyRs at extrasynaptic loci.
Premotor Correlates of Integrated Feedback Control for Eye–Head Gaze Shifts
Authors: Sylvestre Pierre A. , Cullen Kathleen E.
Published: May 2006

Simple activities like picking up the morning newspaper or catching a ball require finely coordinated movements of multiple body segments. How our brain readily achieves such kinematically complex yet remarkably precise multijoint movements remains a fundamental and unresolved question in neuroscience. Many prevailing theoretical frameworks ensure multijoint coordination by means of integrative feedback control. However, to date, it has proven both technically and conceptually difficult to determine whether the activity of motor circuits is consistent with integrated feedback coding. Here, we tested this proposal using coordinated eye–head gaze shifts as an example behavior. Individual neurons in the premotor network that command saccadic eye movements were recorded in monkeys trained to make voluntary eye–head gaze shifts. Head-movement feedback was experimentally controlled by unexpectedly and transiently altering the head trajectory midflight during a subset of movements. We found that the duration and dynamics of neuronal responses were appropriately updated following head perturbations to preserve global movement accuracy. Perturbation-induced increases in gaze shift durations were accompanied by equivalent changes in response durations so that neuronal activity remained tightly synchronized to gaze shift offset. In addition, the saccadic command signal was updated on-line in response to head perturbations applied during gaze shifts. Nearly instantaneous updating of responses, coupled with longer latency changes in overall discharge durations, indicated the convergence of at least two levels of feedback. We propose that this strategy is likely to have analogs in other motor systems and provides the flexibility required for fine-tuning goal-directed movements.
Plasticity-Associated GeneKrox24/Zif268Is Required for Long-Lasting Behavioral Effects of Cocaine
Authors: Valjent Emmanuel , Aubier Benjamin , Corbillé Anne-Gaëlle , Brami-Cherrier Karen , Caboche Jocelyne , Topilko Piotr , Girault Jean-Antoine , Hervé Denis
Published: May 2006

The extracellular signal-regulated kinases (ERKs) 1/2 pathway is stimulated by drugs of abuse in striatal neurons through coincident activation of dopamine D1and glutamate NMDA receptors and is critical for long-lasting behavioral effects of these drugs. Although regulation of transcription is a major target of ERK, the precise mechanisms by which it contributes to behavioral alterations is not known. We examined the role ofZif268, an immediate-early gene induced by drugs of abuse under the control of ERK, in behavioral responses to cocaine using knock-in mutant mice in whichZif268was replaced byLacZ. No biochemical or behavioral differences between mutant and wild-type mice were observed in basal conditions or in acute responses to cocaine injection. In contrast, locomotor sensitization to single or repeated cocaine injections was dramatically diminished in both heterozygous and homozygousZif268mutant mice. Conditioned place preference in response to cocaine was prevented inZif268-deficient mice. This effect was not attributable to a general learning deficit because the mutant mice displayed normal conditioned place preference when food was used as reward. Our results provide direct genetic evidence for the requirement ofZif268for long-lasting association of environmental context with specific behavioral responses after short exposures to cocaine. They also underline the common molecular machinery involved in long-lasting drug-induced behavioral alterations and the formation of other types of memory.
Modulation of peroxisome proliferator-activated receptor δ and γ transcripts in swine endometrial tissue during early gestation
Authors: Lord Etienne , Murphy Bruce D , Desmarais Joëlle A , Ledoux Sandra , Beaudry Danièle , Palin Marie-France
Published: May 2006

Recent evidence points to a role for peroxisome proliferator-activated receptors (PPARs) δ and γ in embryo implantation and survival. In this study, we report the porcine PPARδ complete coding sequence and mRNA abundance of PPARδ, PPARγ1 and γ2, angiopoietin-like protein 4 (ANGPTL4) and adipocyte determination and differentiation-dependent factor 1 (ADD1) genes in the pregnant sow endometrium. Real-time PCR analysis was used to study the effect of parity (Yorkshire-Landrace multiparous (YL) and nulliparous (YLn)), site of endometrial tissue sampling (between and at embryo attachment sites) in crossbred Duroc×Yorkshire-Landrace (DYL) sows and stages of pregnancy (non-pregnant, day 15 and day 25 after mating) in Meishan-Landrace (ML) on mRNA levels. Parity effects were observed for PPARδ, ANGPTL4, and ADD1, with higher mRNA levels in YL than YLn sows. In DYL sows, lower mRNA levels were present at attachment sites compared to between attachment sites for PPARδ, PPARγ1, and ANGPTL4. Finally, day 15 pregnant ML sows had lower PPARδ mRNA levels compared to day 15 cycling ML sows. A significant increase of PPARγ1 mRNA levels was found on day 25 pregnant ML and DYL sows relative to day 15 ML or DYL pregnant sows. PPARδ and γ immunostaining was detected in endometrial tissue of day 15 cycling sows, day 15 and 25 pregnant sows and epithelial cells of day 25 embryos. Collectively, our results suggest a role for PPARδ, PPARγ1, and ANGPTL4, but not PPARγ2, during the peri-implantation period in pregnant sows.
Expression and adaptive regulation of amino acid transport system A in a placental cell line under amino acid restriction
Authors: Jones H N , Ashworth C J , Page K R , McArdle H J
Published: May 2006

Trans-placental transport of amino acids is vital for the developing fetus. Using the BeWo cell line as a placental model, we investigated the effect of restricting amino acid availability on amino acid transport system type A. BeWo cells were cultured either in amino acid-depleted (without non-essential amino acids) or control media for 1, 3, 5 or 6 h. System A function was analysed using α(methyl-amino)isobutyric acid (MeAIB) transcellular transport studies. Transporter (sodium coupled neutral amino acid transporter (SNAT1/2)) expression was analysed at mRNA and protein level by Northern and Western blotting respectively. Localisation was carried out using immunocytochemistry. MeAIB transcellular transport was significantly (P < 0.05) increased by incubation of the cells in amino acid-depleted medium for 1 h, and longer incubation times caused further increases in the rate of transfer. However, the initial response was not accompanied by an increase in SNAT2 mRNA; this occurred only after 3 h and further increased for the rest of the 6-h incubation. Similarly, it took several hours for a significant increase in SNAT2 protein expression. In contrast, relocalisation of existing SNAT2 transporters occurred within 30 min of amino acid restriction and continued throughout the 6-h incubation. When the cells were incubated in medium with even lower amino acid levels (without non-essential plus 0.5 × essential amino acids), SNAT2 mRNA levels showed further significant (P < 0.0001) up-regulation. However, incubation of cells in depleted medium for 6 h caused a significant (P = 0.014) decrease in the expression of SNAT1 mRNA. System L type amino acid transporter 2 (LAT2) expression was not changed by amino acid restriction, indicating that the responses seen in the system A transporters were not a general cell response. These data have shown that placental cells adapt in vitro to nutritional stress and have identified the physiological, biochemical and genomic mechanisms involved.
Developmental and molecular correlates of bovine preimplantation embryos
Authors: Sagirkaya Hakan , Misirlioglu Muge , Kaya Abdullah , First Neal L , Parrish John J , Memili Erdogan
Published: May 2006

Expression of embryonic genes is altered in different culture conditions, which influence developmental potential both during preimplantation and fetal development. The objective of this study was to define the effects of culture conditions on: bovine embryonic development to blastocyst stage, blastocyst cell number, apoptosis and expression patterns of a panel of developmentally important genes. Bovine embryos were cultured in vitro in three culture media containing amino acids, namely potassium simplex optimization medium (KSOMaa), Charles Rosenkrans 1 (CR1aa) and synthetic oviductal fluid (SOFaa). Apoptosis in blastocysts was determined by TUNEL assay and expression profiles of developmentally important genes were assayed by real-time PCR. In vivo-produced bovine blastocysts were used as controls for experiments determining gene expression patterns. While the cleavage rates did not differ, embryos cultured in SOFaa had higher rates of development to blastocyst stage (P < 0.05). Mean cell numbers and percentages of apoptotic cells per blastocyst did not differ among the groups. Expression of the heat shock protein 70 (Hsp70) gene was significantly up-regulated in both CR1aa and KSOMaa when compared with SOFaa (P < 0.001). DNA methyltransferase 3a (Dnmt3a) expression was higher in embryos cultured in CR1aa than in those cultured in SOFaa (P < 0.001). Expression of interferon tau (IF-τ) and insulin-like growth factor II receptor (Igf-2r) genes was significantly up-regulated in KSOMaa when compared with CR1aa (P < 0.001). Gene expression did not differ between in vivo-derived blastocysts and their in vitro-derived counterparts. In conclusion, SOFaa supports higher development to blastocyst stage than KSOMaa and CR1aa, and the culture conditions influence gene expression.
Alternative Paths to Hearing (A Conjecture). Photonic and Tactile Hearing Systems Displaying the Frequency Spectrum of Sound
Authors: Hara E. H.
Published: May 2006

In this article, the hearing process is considered from a system engineering perspective. For those with total hearing loss, a cochlear implant is the only direct remedy. It first acts as a spectrum analyser and then electronically stimulates the neurons in the cochlea with a number of electrodes. Each electrode carries information on the separate frequency bands (i.e., spectrum) of the original sound signal. The neurons then relay the signals in a parallel manner to the section of the brain where sound signals are processed. Photonic and tactile hearing systems displaying the spectrum of sound are proposed as alternative paths to the section of the brain that processes sound. In view of the plasticity of the brain, which can rewire itself, the following conjectures are offered. After a certain period of training, a person without the ability to hear should be able to decipher the patterns of photonic or tactile displays of the sound spectrum and learn to ‘hear’. This is very similar to the case of a blind person learning to ‘read’ by recognizing the patterns created by the series of bumps as their fingers scan the Braille writing. The conjectures are yet to be tested. Designs of photonic and tactile systems displaying the sound spectrum are outlined.
Thermally stimulated luminescence and electron paramagnetic resonance studies of Eu3+-doped yttrium borate
Authors: Anitha M. , Mohapatra Manoj , Kadam R.M. , Seshagiri T.K. , Tyagi A.K. , Natarajan V.
Published: May 2006

Thermally stimulated luminescence (TSL) and electron paramagnetic resonance (EPR) studies were carried out on gamma-irradiated europium-doped yttrium borate samples in the temperature range 300–600 K. TSL studies showed the presence of two glow peaks, a relatively weaker one at 390 K and an intense one at around 550 K. Room-temperature EPR spectrum of irradiated samples revealed the formation of two hole trapped radicals, namely, BO32− and O2−. Temperature variation studies showed drastic reduction in the EPR signal intensities of these radicals around 390 and 550 K indicating thermal destruction of O2− and BO32− radicals, respectively. The observed TSL emission is caused by the recombination of thermally released holes from O2− and BO32− radical ions with electrons. The energy released in electron-hole recombination process is used for the excitation of Eu3+ ion resulting in TSL glow peaks. TSL emission studies confirmed that Eu3+ acts as luminescent center for both the peaks.
High-resolution picosecond acoustic microscopy for non-invasive characterization of buried interfaces
Authors: Ramanathan Shriram , Cahill David G.
Published: May 2006

Non-destructive investigation of buried interfaces at high-resolution is critical for integrated circuit and advanced packaging research and development. In this letter, we present a novel non-contact microscopy technique using ultrahigh frequency (GHz range) longitudinal acoustic pulses to form images of interfaces and layers buried deep inside a silicon device. This method overcomes fundamental limitations of conventional scanning acoustic microscopy by directly generating and detecting the acoustic waves on the surface of the sample using an ultrafast pump-probe optical technique. We demonstrate our method by imaging copper lines buried beneath a 6-μm silicon wafer; the lateral spatial resolution of 3 μm is limited by the laser spot size. In addition to the high lateral spatial resolution, the technique has picosecond (ps) time resolution and therefore will enable imaging individual interconnect layers in multi-layer stacked devices.
Thermal expansion and sintering studies of Nd2-xCexCuO4±δ (0 ≤ x ≤ 0.20)
Authors: Soorie M. , Skinner S.J.
Published: May 2006

Sintering behavior and thermal expansion properties of the solid solution series Nd2-xCexCuO4±δ (0 ≤ x ≤ 0.20) have been investigated over the temperature range of 298 to 1100 K. Significant anisotropy in the lattice expansion coefficient in the a/b and c crystallographic axes was noted on increasing Ce content, which is consistent with the tetragonal unit cell. The lattice expansion in the c axis was found to decrease on increasing temperature for compositions up to x = 0.10, which is likely to be from variations in the oxygen stoichiometry. A variation in the sintering behavior was also noted on varying Ce content, with the onset of sintering temperature reaching a maximum at x = 0.10. A secondary sintering stage was noted for compositions with x > 0.10. Associated with the introduction of a secondary stage on sintering is an overall increase in the temperature at which the sintering is at a maximum.
Functional organogels from lipophilic L-glutamide derivative immobilized on cyclotriphosphazene core
Authors: Shirosaki Tomohiro , Chowdhury Saleh , Takafuji Makoto , Alekperov Dzhamil , Popova Galina , Hachisako Hiroshi , Ihara Hirotaka
Published: May 2006

A novel cyclotriphosphazene-based low-molecular weight organogelator was prepared by immobilization of six dialkylated L-glutamide derivatives on a cyclotriphosphazene core, and its ability as a self-assembling organogelator was investigated. The organogelator exhibited enhanced gelation ability and chirality, and thixotropic property for self-restoring to a gel state; this was compared to the corresponding L-glutamide-derived organogelator without the core. The gelation test, transmission electron microscopy observation, and circular dichroism (CD) spectral study showed that the gelation and aggregation ability were enhanced by immobilization onto the cyclotriphosphazene core. Gels in chloroform and cyclohexane-ethanol (95:5) mixture showed an unusual thixotropic property.
Best Practices in Care Management for Asian American Elders: The Case of Alzheimer’s Disease
Authors: Arnsberger Pamela
Published: May 2006

This article addresses practice concerns and special issues for professionals doing case management for older Asian Americans using Alzheimer’s disease as the case example. Highlighted are cross-cultural issues in assessment for depression in this population, as well as caregiving and community service utilization issues. The research is based on the author’s own work and the literature, as well as results from a population-based study of caregivers of the elderly in California.