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Selected AbstractsThe motility of glioblastoma tumour cells is modulated by intracellular cofilin expression in a concentration-dependent mannerCYTOSKELETON, Issue 3 2005Celestial T. Yap Abstract The invasive behaviour of tumour cells has been attributed in part to dysregulated cell motility. Members of the ADF/Cofilin family of actin-binding proteins are known to increase microfilament dynamics by increasing the rate at which actin monomers leave the pointed end of the filament and by a filament-severing activity. As depolymerisation is a rate-limiting step in actin dynamics, ADF/Cofilins are suspected to facilitate the motility of cells. To test this, we investigated the influence of cofilin on tumour motility by transient and stably overexpressing cofilin in the human glioblastoma cell line, U373 MG. Several different methods were used to ascertain the level of cofilin in overexpressing clones and this was correlated with their rate of random locomotion. A biphasic relationship between cofilin level and locomotory rate was found. Clones that displayed a moderate amount of overproduction of cofilin were found to have increased rates of locomotion approximately linear to the overproduction of cofilin up to an optimal cofilin level of about 4.5 times that of wild type cells at which the cells were almost twice as fast. However, clones producing more than this optimal amount were found to locomote at progressively reduced speeds. Cells that overexpress cofilin have reduced stress fibres compared to control cells showing that the excess cofilin affects the actin cytoskeleton. We conclude that overexpression of cofilin enhances the motility of glioblastoma tumour cells in a concentration-dependent fashion, which is likely to contribute to their invasiveness. Cell Motil. Cytoskeleton 60:153,165, 2005. © 2005 Wiley-Liss, Inc. [source] Home Asthma Management for Rural FamiliesJOURNAL FOR SPECIALISTS IN PEDIATRIC NURSING, Issue 2 2003Sharon D. Horner ISSUES AND PURPOSE. To assess home asthma management among rural families with a school-age child who has asthma. DESIGN AND METHODS. Exploratory analysis of baseline data of a tri-ethnic sample of rural families with school-age children who have asthma. RESULTS. Parents and children enact a moderate amount of asthma management behaviors. Preventive behaviors were correlated with the Asthma Behavior Inventory and treatment behaviors were correlated with the child's asthma severity. Factors that could affect asthma management include no insurance, no visits to providers in 12 months, or no asthma medications. PRACTICE IMPLICATIONS. Nurses must use every contact with families to assess their asthma management and availability of resources, and to determine the fit between asthma severity and the asthma management plan. [source] Multiscale patterns of movement in fragmented landscapes and consequences on demography of the snail kite in FloridaJOURNAL OF ANIMAL ECOLOGY, Issue 2 2006JULIEN MARTIN Summary 1Habitat loss and fragmentation are major factors affecting vertebrate populations. A major effect of these habitat alterations is that they reduce movement of organisms. Despite the accepted importance of movement in driving the dynamics of many natural populations, movement of vertebrates in fragmented landscapes have seldom been estimated with robust statistical methods. 2We estimated movement probabilities of snail kites Rosthramus sociabilis within the remaining wetlands in Florida. Using both radio-telemetry and banding information, we used a multistate modelling approach to estimate transition probabilities at two temporal scales (month; year) and multiple spatial scales. We examined kite movement among wetlands altered by three different levels of fragmentation: among wetlands separated by small physical barriers (e.g. road); among wetlands separated by moderate amount of matrix (< 5 km); and among wetlands separated by extensive matrix areas (> 15 km). 3Kites moved extensively among contiguous wetlands (movement probability 0·29 per month), but significantly less among isolated wetlands (movement probability 0·10 per month). 4Kites showed high levels of annual site fidelity to most isolated wetlands (probability ranged from 0·72 to 0·95 per year). 5We tested the effects of patch size and interpatch distance on movement. Our modelling indicated an effect of both distance and patch size on juveniles' movement (but not adult) when examining movements among fragments. 6Only a small proportion of kites escaped a regional drought by moving to refugia (wetlands less affected by drought). Many individuals died after the drought. During drought adult survival dropped by 16% while juvenile survival dropped by 86% (possibly because juveniles were less likely to reach refugia). 7We hypothesize that fragmentation may decrease kite's resistance to drought by restricting exploratory behaviour. [source] Rotamer optimization for protein design through MAP estimation and problem-size reductionJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 12 2009Eun-Jong Hong Abstract The search for the global minimum energy conformation (GMEC) of protein side chains is an important computational challenge in protein structure prediction and design. Using rotamer models, the problem is formulated as a NP-hard optimization problem. Dead-end elimination (DEE) methods combined with systematic A* search (DEE/A*) has proven useful, but may not be strong enough as we attempt to solve protein design problems where a large number of similar rotamers is eligible and the network of interactions between residues is dense. In this work, we present an exact solution method, named BroMAP (branch-and-bound rotamer optimization using MAP estimation), for such protein design problems. The design goal of BroMAP is to be able to expand smaller search trees than conventional branch-and-bound methods while performing only a moderate amount of computation in each node, thereby reducing the total running time. To achieve that, BroMAP attempts reduction of the problem size within each node through DEE and elimination by lower bounds from approximate maximum-a-posteriori (MAP) estimation. The lower bounds are also exploited in branching and subproblem selection for fast discovery of strong upper bounds. Our computational results show that BroMAP tends to be faster than DEE/A* for large protein design cases. BroMAP also solved cases that were not solved by DEE/A* within the maximum allowed time, and did not incur significant disadvantage for cases where DEE/A* performed well. Therefore, BroMAP is particularly applicable to large protein design problems where DEE/A* struggles and can also substitute for DEE/A* in general GMEC search. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009 [source] Industrial tools for the feature location problem: an exploratory studyJOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 6 2006Sharon Simmons Abstract Software engineers who maintain and enhance large systems often encounter the feature location problem: where in the many thousands of lines of code is a particular user feature implemented? Several methods of addressing the problem have been proposed, most of which involve tracing the execution of the system and analyzing the traces. Some supporting academic tools are available. However, companies that depend on the successful evolution of large systems are more likely to use new methods if they are supported by industrial-strength tools of known reliability. This article describes a study performed with Motorola, Inc. to see whether there were any pitfalls in using Metrowerks CodeTEST and Klocwork inSight for feature location on message-passing software similar to systems that Motorola maintains. These two tools were combined with TraceGraph, an academic trace comparison tool. The study identified two main problems. First, some ,glue' code and workarounds were needed to get CodeTEST to generate a trace for an interval of time in which the feature was operating. Second, getting information out of TraceGraph and into inSight was needlessly complicated for a user. However, with a moderate amount of work, the tool combination was effective in locating, understanding and documenting features. Study participants completed these steps in typically 3,4 hours per feature, studying only a few hundred lines out of a 200,000 line system. An ongoing project with Motorola is focused on improving tool integration with the hope of making feature location common practice at Motorola. Copyright © 2006 John Wiley & Sons, Ltd. [source] Angiomyofibroblastoma-like tumor (lipomatous variant) of the inguinal region of a male patientPATHOLOGY INTERNATIONAL, Issue 9 2002Masayuki Shintaku A case of angiomyofibroblastoma-like tumor (lipomatous variant) that arose in the subcutis of the inguinal region of a 45-year-old man is presented. The maximum dimension of the tumor measured 39 mm and it was well circumscribed. Histopathological examination revealed a close admixture of plump spindle or stellate cells and mature adipocytes. These were arranged haphazardly or formed interconnecting thin cellular trabeculae on the myxoid or edematous background. The tumor was highly vascularized and contained a moderate amount of collagen fibers. Immunohistochemically, the tumor cells were positive for vimentin, CD34 and the estrogen receptor, but negative for ,-smooth muscle actin and desmin. The differential diagnosis between the lipomatous variant of angiomyofibroblastoma and cellular angiofibroma or spindle cell lipoma is discussed, and the pathogenetic hypotheses about the occurrence of mature adipocytes within benign fibroblastic or myofibroblastic neoplasms are mentioned briefly. It is important for surgical pathologists to be acquainted with the occasional presence of adipocytes in these neoplasms to avoid misinterpretation. [source] Effect of the Photoperiod and Administration of Melatonin on the Pars Tuberalis of Viscacha (Lagostomus maximus maximus): An Ultrastructural StudyTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 5 2010Edith Perez Romera Abstract The pituitary pars tuberalis (PT) is a glandular zone exhibiting well-defined structural characteristics. Morphologically, it is formed by specific secretory cells, folliculostellate cells, and migratory cells coming from the pars distalis. The purpose of this work was to investigate differences in specific cellular characteristics in the PT of viscachas captured in summer (long photoperiod) and winter (short photoperiod), as well as the effects of chronic melatonin administration in viscachas captured in summer and kept under long photoperiod. In summer, the PT-specific cells exhibited cell-like characteristics with an important secretory activity and a moderate amount of glycogen. In winter, the PT-specific granulated cells showed ultrastructural variations with signs of a reduced synthesis activity. Also, PT showed a high amount of glycogen and a great number of cells in degeneration. After melatonin administration, the ultrastructural characteristics were similar to those observed in winter, but the amount of glycogen was higher. These results suggest possible functional implications as a result of morphological differences between long and short photoperiods, and are in agreement with the variations of the pituitary-gonadal axis, probably in response to the natural photoperiod changes through the pineal melatonin. The ultrastructural differences observed in PT, after melatonin administration, were similar to those observed in the short photoperiod, thus supporting the hypothesis that these cytological changes are induced by melatonin. Anat Rec, 293:871,878, 2010. © 2010 Wiley-Liss, Inc. [source] Familial associations of intense preoccupations, an empirical factor of the restricted, repetitive behaviors and interests domain of autismTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 8 2009Christopher J. Smith Background:, Clinical heterogeneity of autism likely hinders efforts to find genes associated with this complex psychiatric disorder. Some studies have produced promising results by restricting the sample according to the expression of specific familial factors or components of autism. Previous factor analyses of the restricted, repetitive behaviors and interest (RRBI) domain of autism have consistently identified a two-factor model that explains a moderate amount of variance. The identification of additional factors may explain more variance in the RRBI domain and provide an additional component of autism that may help in the identification of underlying genetic association. Methods:, We conducted factor analyses of RRBI symptoms with a sample that included verbal subjects meeting full criteria for autism aged 5 to 22 years (n = 245). Among affected sibling pairs (n = 126) we examined the familial aggregation of the identified factors. We also examined the associations of the factors with autism-related personality traits in fathers and mothers (n = 50). Results:, The previously identified two-factor model , insistence on sameness (IS) and repetitive stereotypic motor behaviors (RSMB) , was replicated in our sample. Next, a second factor analysis that included the item for verbal rituals resulted in a four-factor model , IS, ,simple' RSMB, ,complex' RSMB, and a fourth factor including symptoms associated with intense preoccupations (IP). Of these four, both IS and IP were significantly familial among affected siblings, but only IP was significantly correlated with the broader autism phenotype traits of rigidity and aloofness in fathers. Conclusions:, The results support previous evidence for the IS factor, its familiality, and the identification of IP as an additional strong candidate trait for genetic studies of autism. [source] Controlled Synthesis of Water-Dispersible Faceted Crystalline Copper Nanoparticles and Their Catalytic PropertiesCHEMISTRY - A EUROPEAN JOURNAL, Issue 35 2010Dr. Yanfei Wang Abstract We report a solution-phase synthetic route to copper nanoparticles with controllable size and shape. The synthesis of the nanoparticles is achieved by the reduction of copper(II) salt in aqueous solution with hydrazine under air atmosphere in the presence of poly(acrylic acid) (PAA) as capping agent. The results suggest that the pH plays a key role for the formation of pure copper nanoparticles, whereas the concentration of PAA is important for controlling the size and geometric shape of the nanoparticles. The average size of the copper nanoparticles can be varied from 30 to 80,nm, depending on the concentration of PAA. With a moderate amount of PAA, faceted crystalline copper nanoparticles are obtained. The as-synthesized copper nanoparticles appear red in color and are stable for weeks, as confirmed by UV/Vis and X-ray photoemission (XPS) spectroscopy. The faceted crystalline copper nanoparticles serve as an effective catalyst for N-arylation of heterocycles, such as the CN coupling reaction between p -nitrobenzyl chloride and morpholine producing 4-(4-nitrophenyl)morpholine in an excellent yield under mild reaction conditions. Furthermore, the nanoparticles are proven to be versatile as they also effectively catalyze the three-component, one-pot Mannich reaction between p -substituted benzaldehyde, aniline, and acetophenone affording a 100,% conversion of the limiting reactant (aniline). [source] Fine-needle aspiration biopsy findings in sclerosing polycystic adenosis of the parotid glandDIAGNOSTIC CYTOPATHOLOGY, Issue 7 2007Demet Etit M.D. Abstract Sclerosing polycystic adenosis (SPA) is a recently described, rare lesion of the salivary gland analogous to fibrocystic disease of the breast. Recognition of this benign entity is important since the differential diagnosis includes other more common benign and malignant salivary gland neoplasms, particularly mucoepidermoid carcinoma and tumors with cystic and oncocytic features. While the histomorphology of SPA is well documented, there is only one other cytologic description of SPA in the English-language literature. Here we describe the fine-needle aspiration biopsy findings in a case of SPA of the parotid gland in an 84-year-old woman. The aspirate was characterized by flat cohesive sheets of epithelial cells with moderate amounts of finely granular oncocytic cytoplasm and enlarged round nuclei with indistinct nucleoli. Some epithelial groups formed glandular structures with lumens, and the background contained small amounts of delicate mucoproteinaceous material. Occasional markedly vacuolated cells were present as well as many cells with apocrine change manifested by well-defined apical snouting. Familiarity with the cytomorphologic features of SPA, including its characteristic apocrine changes, is important for distinguishing it from other more clinically significant salivary gland lesions. Diagn. Cytopathol. 2007;35:444,447. © 2007 Wiley-Liss, Inc. [source] Social categorization and fit detection under cognitive load: efficient or effortful?EUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 4 2005Karl Christoph Klauer Participants perceived a discussion between members of two social categories in a name-matching paradigm. Discussions either exhibited inter-category fit, defined as a covariation of category membership and the category members' attitude positions, or not. Orthogonally, there was cognitive load at encoding, load at retrieval, or no concurrent load. Memory for the statements and memory for the speaker of a statement were affected by load with little evidence for fit effects. Conversely, category memory, reconstructive category guessing and perceived fit were affected by inter-category fit with little evidence for load effects. The results suggest that category activation is sensitive to inter-category fit and that fit detection is robust against moderate amounts of cognitive load. Copyright © 2005 John Wiley & Sons, Ltd. [source] Physico-chemical properties of molten dimer ascorbate oxidaseFEBS JOURNAL, Issue 22 2006Eleonora Nicolai The possible presence of dimeric unfolding intermediates might offer a clue to understanding the relationship between tertiary and quaternary structure formation in dimers. Ascorbate oxidase is a large dimeric enzyme that displays such an intermediate along its unfolding pathway. In this study the combined effect of high pressure and denaturing agents gave new insight on this intermediate and on the mechanism of its formation. The transition from native dimer to the dimeric intermediate is characterized by the release of copper ions forming the tri-nuclear copper center located at the interface between domain 2 and 3 of each subunit. This transition, which is pH-dependent, is accompanied by a decrease in volume, probably associated to electrostriction due to the loosening of intra-subunit electrostatic interactions. The dimeric species is present even at 3 × 108 Pa, providing evidence that mechanically or chemically induced unfolding lead to a similar intermediate state. Instead, dissociation occurs with an extremely large and negative volume change (,V , ,200 mL·mol,1) by pressurization in the presence of moderate amounts of denaturant. This volume change can be ascribed to the elimination of voids at the subunit interface. Furthermore, the combination of guanidine and high pressure uncovers the presence of a marginally stable (,G , 2 kcal·mol,1) monomeric species (which was not observed in previous equilibrium unfolding measurements) that might be populated in the early folding steps of ascorbate oxidase. These findings provide new aspects of the protein folding pathway, further supporting the important role of quaternary interactions in the folding strategy of large dimeric enzymes. [source] Palatability of macrophytes to the invasive freshwater snail Pomacea canaliculata: differential effects of multiple plant traitsFRESHWATER BIOLOGY, Issue 10 2010PAK KI WONG Summary 1.,By selective grazing, invasive grazers can alter macrophyte-herbivore relationships in shallow freshwater bodies. Evaluating the palatability of macrophytes and understanding the determinants of plant palatability can help predict grazing impact. In no-choice feeding assays, we tested the palatability of 21 species of freshwater macrophytes to the invasive freshwater apple snail Pomacea canaliculata. 2.,Daily feeding rate varied greatly with plant species, ranging from 1.1 to 22% of snail body mass. We assessed six plant properties and examined their correlation with feeding rate. Total nitrogen content was positively related, and C:N ratio and dry matter content (DMC) negatively related, to snail feeding rate. There was no significant correlation between snail feeding rate and plant phenolic content, but the feeding rate on Myriophyllum aquaticum (the plant with the highest phenolic content) was very low. 3.,We repeated the feeding assays for 15 species that were not palatable as fresh leaves with reconstituted plant tissues formed by mixing ground up dried leaves with agar. The feeding rate still differed greatly among macrophyte species. Phragmites australis and Vallisneria natans (two species with the highest DMC) were eaten much more as reconstituted plant than as fresh leaves, indicating that structure (i.e. DMC) may be important in their defence against snail herbivory. For two plants (M. aquaticum and Alternanthera philoxeroides) that had moderate amounts of nitrogen/phosphorus but were consumed very little as fresh and reconstituted tissues, we incorporated their extracts into a palatable agar-based food. The extracts from both species greatly reduced snail feeding rate, indicating the presence of chemical defences in these two species. 4.,These results indicated that feeding was affected by several plant traits. The snail favoured plants with a high nitrogen content and avoided plants with a high DMC. Only a few plants possessed chemical feeding deterrents that were effective against this snail. Given the invasive spread of P. canaliculata in Asia, ecologists and managers should consider plant palatability when selecting plants for use in wetland restoration and when predicting the impact of further invasion by this species. [source] Carcinomas arising in multilocular thymic cysts of the neck: a clinicopathological study of three casesHISTOPATHOLOGY, Issue 1 2004C A Moran Aims :,To report three cases of primary carcinoma of the neck arising in multilocular thymic cysts (MTC). Methods and results :,The patients were three men aged 47, 50 and 52 years who presented with a painless neck mass of several weeks' duration. The patients had no history of previous surgical procedures or of malignancy elsewhere. The tumours in all three patients were located on the right lateral side of the neck; all patients underwent complete surgical resection of the mass. Grossly, the tumours were cystic and measured between 20 and 30 mm in greatest diameter. Histologically, the tumours showed cyst walls lined by squamous epithelium. The cyst walls contained prominent germinal centres with lymphoid hyperplasia, cholesterol cleft granulomas, and scattered keratinized structures reminiscent of Hassall's corpuscles. In addition, a neoplastic cellular proliferation composed of round to oval cells arranged in sheets and originating from the lining of the cystic structures was present. The neoplastic cells showed moderate amounts of eosinophilic cytoplasm, round nuclei, and, in some areas, prominent nucleoli. Mitotic figures were easily found, and cellular pleomorphism was present in several areas. In two cases the tumours showed features of basaloid carcinoma of the thymus, while in one case the pattern was that of squamous cell carcinoma. Immunohistochemical studies for keratin showed a strong positive reaction in the tumour cells, while leucocyte common antigen strongly stained the lymphoid background. Follow-up information obtained in two patients showed them to be alive 6 months after initial diagnosis. One patient was lost to follow-up. Conclusion :,The cases described here represent an unusual variant of carcinoma arising in multilocular thymic cyst in the neck region. [source] Lateral ridge augmentation by the use of grafts comprised of autologous bone or a biomaterial.JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 12 2002An experiment in the dog Abstract Objective: The present investigation was performed to determine if a block of Bio-Oss® used as an onlay graft can be used as a scaffold for new bone formation. Material and methods: Five mongrel dogs were used. The mandibular premolars were extracted. On both sides of the mandible, the buccal bone plate was resected and defects, about 25 mm long, 8 mm high and 5 mm wide, were produced After 3 months of healing, a second surgical procedure was performed. In the left side, a block of Bio-Oss® was adjusted to the buccal bone wall. The graft had the shape of a cylinder and was retained with a miniscrew and covered with a collagen membrane. In the contra-lateral side of the mandible, a block biopsy was first obtained from the ascending ramus. This bone graft had the shape of a cylinder that was 8 mm in diameter and 3 mm thick. The graft was transferred to the experimental site, adjusted to the buccal wall, retained with a miniscrew, and covered with a membrane. The flaps were repositioned and closed with sutures to ensure a complete coverage of the experimental sites. After 6 months of healing, the dogs were sacrificed and the experimental sites dissected. The biopsies were processed for ground sectioning. The sections were stained in toluidine blue, examined in the microscope, and a number of histo- and morphometric assessments made. Results: The study demonstrated that cortical bone used as an onlay graft in the lateral aspect of the alveolar ridge, during a 6-month period of healing integrated with the host bone but underwent marked peripheral resorption. Thus, close to 30% of the height and 50% of the length of the graft was replaced with connective tissue. It was further observed that while the dimensions of a graft which contained a scaffold of cancellous bovine bone mineral remained unchanged, only moderate amounts of new bone formed at the base of this graft. Conclusion: Grafts of autologous cortical bone, placed on the surface of a one-wall defect, may undergo marked resorption during healing. A similar graft of Bio-Oss® may retain its dimension, and limited amounts of new bone will form within the biomaterial. [source] Lymphoepithelioma-Like Carcinoma of the Skin: A Case ReportJOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2005T. Mitsuhashi Lymphoepithelioma-like carcinoma of the skin is a rare tumor with a microscopic resemblance to lymphoepitheliomatous carcinoma of the nasopharynx. We present a 93-year-old man with papules on the left auricle to the cheek that were gradually enlarged. By the time of a biopsy, it grew to a 5.0 × 3.0 × 2.8 cm dark red mass, and necrotic debris was attached to the surface. Histologically, a relatively well-demarcated, dermal-hypodermic multiple lobules were composed of irregular islands of atypical epithelial cells. The uniform tumor cells had moderate amounts of lightly eosinophilic cytoplasm and vesicular nuclei with one or two prominent nucleoli. A dense lymphocytic infiltrate was present within the neoplastic islands, obscuring the epithelial component. The neoplastic cells were unconnected to the overlying epidermis. Neither squamous nor glandular differentiation was present. Immunohistochemically, the neoplastic cells were positive for epithelial membrane antigen and cytokeratin, and negative for latent membrane protein 1. No Epstein-Barr virus-encoded RNA (EBER) was detected by in situ hybridization. The negativity for Epstein-Barr virus may be a help in the differential diagnosis from metastatic undifferentiated nasopharyngeal carcinoma, which is uniformly positive for EBER. [source] Glomus Coccygeum: Report of a CaseJOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2005A. Rahemtullah The glomus coccygeum is a vestigial structure related to the canals of Sucquet-Hoyer, an arteriovenous anastomosis surrounded by glomus cells derived from modified smooth muscle and involved in thermoregulation. It is an incidental finding in specimens from the sacral area and may represent a diagnostic challenge to the unaware observer. We present a case of a glomus coccygeum, presenting as a 1.5 mm structure adjacent to a typical pilonidal cyst excised from a 7-month-old boy, that was the subject of a second opinion consultation. The lesion showed small to medium sized clusters of predominantly epithelioid cells with moderate amounts of clear to eosinophilic cytoplasm, intercellular borders and plump, round nuclei with fine chromatin. These cells were closely associated with small vascular channels and nerves. Immunohistochemistry revealed that the epithelioid cells expressed vimentin, muscle-specific actin, neuron-specific enolase, and S-100 protein, were weakly positive for smooth muscle actin, and negative for desmin, synaptophysin and chromogranin. The endothelial cells of the vascular channels were antibody CD31 positive. Recognition of the histological features of glomus coccygeum is important to avoid confusion with glomus tumor and neural or smooth muscle neoplasms in the sacral area. [source] Corticosteroid Effects on Serotonin Responses in Granule Cells of the Rat Dentate GyrusJOURNAL OF NEUROENDOCRINOLOGY, Issue 3 2001Y. J. G. Karten Abstract Granule cells in the rat dentate gyrus contain mineralocorticoid and glucocorticoid receptors to which the adrenal hormone corticosterone binds with differential affinity. These cells also express various receptor-subtypes for serotonin (5-HT), including the 5-HT1A receptor which mediates a membrane hyperpolarization accompanied by a decrease in membrane resistance. Earlier studies have shown that removal of corticosterone by adrenalectomy, particularly in the dentate gyrus, results in enhanced expression of the 5-HT1A receptor mRNA and increased 5-HT1A receptor binding capacity. This was normalized by activation of mineralocorticoid receptors or concurrent activation of both receptor types. In the present, intracellular recording study in vitro, we examined if the altered levels of 5-HT1A receptor mRNA and protein are associated with changes in the response to 5-HT. We found that the hyperpolarization and resistance decrease induced in granule cells by a submaximal (10 µM) dose of 5-HT were unaltered 2,4 days after adrenalectomy, indicating a dissociation between corticosteroid actions on 5-HT1A receptor mRNA/protein levels and functional responses to 5-HT. Subsequent occupation of mineralocorticoid receptors in vitro significantly suppressed the 5-HT induced change in resistance, 1,4 h after steroid application. Compared to this, concurrent activation of glucocorticoid receptors led to large responses to 5-HT. This modulation by steroids was not observed with a higher dose of 5-HT (30 µM). The data suggest that with moderate amounts of 5-HT, corticosteroids affect the information flow through the dentate gyrus such that excitatory transmission is promoted with predominant mineralocorticoid receptor activation and attenuated with additional glucocorticoid receptor occupation. [source] Hippocampal N -Methyl- d -Aspartate Receptor Subunit Expression Profiles in a Mouse Model of Prenatal Alcohol ExposureALCOHOLISM, Issue 2 2010Sabrina L. Samudio-Ruiz Background:, Although several reports have been published showing prenatal ethanol exposure is associated with alterations in N -methyl- d- aspartate (NMDA) receptor subunit levels and, in a few cases, subcellular distribution, results of these studies are conflicting. Methods:, We used semi-quantitative immunoblotting techniques to analyze NMDA receptor NR1, NR2A, and NR2B subunit levels in the adult mouse hippocampal formation isolated from offspring of dams who consumed moderate amounts of ethanol throughout pregnancy. We employed subcellular fractionation and immunoprecipitation techniques to isolate synaptosomal membrane- and postsynaptic density protein-95 (PSD-95)-associated pools of receptor subunits. Results:, We found that, compared to control animals, fetal alcohol-exposed (FAE) adult mice had: (i) increased synaptosomal membrane NR1 levels with no change in association of this subunit with PSD-95 and no difference in total NR1 expression in tissue homogenates; (ii) decreased NR2A subunit levels in hippocampal homogenates, but no alterations in synaptosomal membrane NR2A levels and no change in NR2A-PSD-95 association; and (iii) no change in tissue homogenate or synaptosomal membrane NR2B levels but a reduction in PSD-95-associated NR2B subunits. No alterations were found in mRNA levels of NMDA receptor subunits suggesting that prenatal alcohol-associated differences in subunit protein levels are the result of differences in post-transcriptional regulation of subunit localization. Conclusions:, Our results demonstrate that prenatal alcohol exposure induces selective changes in NMDA receptor subunit levels in specific subcellular locations in the adult mouse hippocampal formation. Of particular interest is the finding of decreased PSD-95-associated NR2B levels, suggesting that synaptic NR2B-containing NMDA receptor concentrations are reduced in FAE animals. This result is consistent with various biochemical, physiological, and behavioral findings that have been linked with prenatal alcohol exposure. [source] Ethanol Self-Administration and Alterations in the Livers of the Cynomolgus Monkey, Macaca fascicularisALCOHOLISM, Issue 1 2007Priscilla Ivester Background: Most of the studies of alcoholic liver disease use models in which animals undergo involuntary administration of high amounts of ethanol and consume diets that are often high in polyunsaturated fatty acids. The objectives of this study were (1) to evaluate whether cynomolgus monkeys (Macaca fascicularis) drinking ethanol voluntarily and consuming a diet with moderate amounts of lipid would demonstrate any indices of alcoholic liver disease past the fatty liver stage and (2) to determine whether these alterations were accompanied by oxidative stress. Methods: Six adult male and 6 adult female cynomolgus monkeys were allowed to consume ethanol voluntarily for 18 to 19 months. Additional monkeys were maintained on the same consumption protocol, but were not provided with ethanol. During the course of the study, liver biopsy samples were monitored for lipid deposition and inflammation, serum for levels of liver enzymes, and urine for concentrations of the isoprostane (IsoP) metabolite, 2,3-dinor-5,6-dihydro-15-F2t -IsoP, a biomarker for oxidative stress. Liver mitochondria were monitored for respiratory control and liver for concentrations of neutral lipids, adenine nucleotides, esterified F2 isoprostanes, oxidized proteins, 4-hydroxynonenal (HNE)-protein adducts, and protein levels of cytochrome P-450 2E1 and 3A4. Results: Ethanol consumption ranged from 0.9 to 4.05 g/kg/d over the period of the study. Serum levels of aspartate amino transferase were elevated in heavy-consuming animals compared with those in ethanol-naďve or moderate drinkers. Many of the ethanol consumers developed fatty liver and most showed loci of inflammation. Both hepatic energy charge and phosphorylation potential were decreased and NADH-linked respiration was slightly, but significantly depressed in coupled mitochondria as a result of heavy ethanol consumption. The urinary concentrations of 2,3-dinor-5,6-dihydro-15-F2t -IsoP increased as high as 33-fold over that observed in ethanol-abstinent animals. Liver cytochrome P-450 2E1 concentrations increased in ethanol consumers, but there were no ethanol-elicited increases in hepatic concentrations of the esterified F2 isoprostanes, oxidized proteins, or HNE-protein adducts. Conclusion: Our studies show that cynomolgus monkeys undergoing voluntary ethanol consumption for 1.5 years exhibit many of the features observed in the early stages of human alcoholic liver disease. Ethanol-elicited fatty liver, inflammation, and elevated serum aspartate amino transferase were evident with a diet that contained modest amounts of polyunsaturated lipids. The dramatic increases in urinary IsoP demonstrated that the animals were being subjected to significant oxidative stress that correlated with their level of ethanol consumption. [source] Clinical Practice Characteristics and Preconception Counseling Strategies of Health Care Providers Who Recommend Alcohol Abstinence During PregnancyALCOHOLISM, Issue 11 2004Suzanne C. Tough Objective: National initiatives on fetal alcohol syndrome in Canada and the United States aimed at prevention, identification, and treatment of individuals who are affected by alcohol exposure in utero recommend that women abstain from consuming alcohol during pregnancy. Health care providers are key educators regarding appropriate alcohol use. The objective of this study was to describe characteristics of physicians who recommend alcohol abstinence during pregnancy with regard to knowledge of fetal alcohol syndrome and preconception counseling strategies. Methods: A survey was mailed to Canadian physicians and midwives between 2001 and 2002. Participants consisted of a national random sample of 1090 Canadian obstetricians and gynecologists, midwives, and family physicians who were current members of provincial and national professional organizations. The main outcome measure was questionnaire responses to knowledge, prevention, and diagnosis of issues related to alcohol use during pregnancy. Results: Response rates ranged from 31.1% among family physicians to 63.5% among midwives. Overall, 91.2% of providers recommended abstinence from alcohol during pregnancy. These providers were significantly more likely to believe that there is sufficient information about alcohol use and that clients were interested in discussing alcohol (p < 0.05). They were also significantly more likely to discuss depression, personal alcohol use, partner's use of alcohol, and family history of alcohol misuse with women of childbearing age (p < 0.05). Once a patient became pregnant, fewer practice differences were noted, although those who recommended alcohol abstinence were significantly more likely to take clinical action when pregnant patients were consuming moderate amounts of alcohol (p < 0.05). Conclusions: It is encouraging that almost 90% of Canadian health care providers recommend abstinence from alcohol during pregnancy. However, differences in clinical practice exist between providers who recommend alcohol abstinence during pregnancy as compared with those who recommend a "glass in moderation." [source] Dietary Cholate Is Required for Antiatherogenic Effects of Ethanol in Mouse ModelsALCOHOLISM, Issue 9 2003Mark A. Deeg Background: Human consumption of moderate amounts of ethanol is associated with reduced cardiovascular events. Studies examining the effect of ethanol on atherosclerosis in mouse models have yielded conflicting results that may be due to differences in dietary fat and cholate content. To determine if dietary cholate influences ethanol's effect on atherosclerosis, we fed apolipoprotein E,/, and low-density lipoprotein receptor (LDLR),/, mice different liquid diets with or without ethanol. Methods: Apolipoprotein E,/, mice were fed a low-fat or high saturated fat, cholate-containing diet with or without ethanol for 3 to 10 weeks, and LDLR,/, mice were fed a low-fat, high saturated fat, or high saturated fat diet with cholate with or without ethanol for 7 weeks. At the end of the feeding study, aortic root lesion size was determined and compared with serum cholesterol, triglycerides, and high-density lipoprotein cholesterol. Because dietary cholate increases hepatic nuclear factor (NF)-,B and ethanol inhibits NF-,B, we also examined the effect of ethanol on aortic NF-,B binding activity. Results: Adding ethanol to a low-fat diet had no effect on lesion size. Similarly, ethanol had no effect on lesion size in LDLR,/, mice consuming a high saturated fat diet. Adding ethanol to a high-fat, cholate-containing diet for either strain resulted in a 25% to 50% reduction in lesion size. Dietary cholate increased and ethanol reduced NF-,B binding activity in the aorta. Conclusions: These results suggest that ethanol inhibits atherosclerosis in the presence of dietary cholate, which may occur via an anti-inflammatory mechanism. [source] New Cyclic Olefin Copolymer for the Preparation of Thermally Responsive Luminescent FilmsMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 9 2009Filippo Donati Abstract Polymer films with optical properties as indicators to thermal stress were obtained through the controlled dispersion of moderate amounts (,0.1 wt.-%) of the 4,4,-bis(2-benzoxazolyl)stilbene (BBS) dye into a new semicrystalline ethylene-norbornene (E - co - N, N content of 15.3 mol.-%) copolymer characterized by a glass transition temperature (Tg) of about 64,°C. All the pristine films showed optical characteristics coming from noninteracting BBS chromophores. In contrast permanent optical changes were detected after film annealing at a T,,,Tg due to the variation of the BBS supramolecular structure. The easy modulation of the optical features of polymer films by thermal perturbations suggests applications as threshold temperature visual indicators in thermoplastic materials. [source] Effects of inductive coupling on parallel MR image reconstructionsMAGNETIC RESONANCE IN MEDICINE, Issue 3 2004Michael A. Ohliger Abstract Theoretical arguments and experimental results are presented that characterize the impact of inductive coupling on the performance of parallel MRI reconstructions. A simple model of MR signal and noise reception suggests that the intrinsic amount of spatial information available from a given coil array is unchanged in the presence of inductive coupling, as long as the sample remains the dominant source of noise for the coupled array. Any loss of distinctness in the measured coil sensitivities is compensated by information stored in the measured noise correlations. Adjustments to the theory are described to account for preamplifier noise contributions. Results are presented from an experimental system in which preamplifier input impedances are systematically adjusted in order to vary the level of coupling between array elements. Parallel image reconstructions using an array with four different levels of coupling and an acceleration factor up to six show average SNR changes of ,7.6% to +7.5%. The modest changes in overall SNR are accompanied by similarly small changes in g-factor. These initial results suggest that moderate amounts of inductive coupling should not have a prohibitive effect on the use of a given coil array for parallel MRI. Magn Reson Med 52:628,639, 2004. © 2004 Wiley-Liss, Inc. [source] Importance of Hydrologic and Landscape Heterogeneity for Restoring Bank Swallow (Riparia riparia) Colonies along the Sacramento River, CaliforniaRESTORATION ECOLOGY, Issue 2 2005Kerry C. Moffatt Abstract Human activities have degraded riparian systems in numerous ways, including homogenization of the floodplain landscape and minimization of extreme flows. We analyzed the effects of changes in these and other factors for extinction,colonization dynamics of a threatened Bank Swallow population along the upper Sacramento River, California, U.S.A. We monitored Bank Swallow distributions along a 160-km stretch of the river from 1986,1992 and 1996,2003 and tested whether site extinctions and colonizations corresponded with changes in maximum river discharge, surrounding land cover, estimated colony size, temperature, and precipitation. Colonization probabilities increased with maximum discharge. Extinction probabilities decreased with proximity to the nearest grassland, decreased with colony size, and increased with maximum discharge. To explore the implications for restoration, we incorporated the statistically estimated effects of distance to grassland and maximum discharge into simple metapopulation models. Under current conditions, the Bank Swallow metapopulation appears to be in continued decline, although stable or increasing numbers cannot be ruled out with the existing data. Maximum likelihood parameters from these regression models suggest that the Sacramento River metapopulation could be restored to 45 colonies through moderate amounts of grassland restoration, large increases in discharge, or direct restoration of nesting habitat by removing approximately 10% of existing bank protection (riprap) from suitable areas. Our results highlight the importance of grassland restoration, mixed benefits of restoring high spring discharge, and the importance of within-colony dynamics as areas for future research. [source] Modeling landscape patterns of understory tree regeneration in the Pacific Northwest, USAAPPLIED VEGETATION SCIENCE, Issue 2 2001Michael C. Wimberly Abstract. Vegetation maps serve as the basis for spatial analysis of forest ecosystems and provide initial information for simulations of forest landscape change. Because of the limitations of current remote sensing technology, it is not possible to directly measure forest understory attributes across large spatial extents. Instead we used a predictive vegetation mapping approach to model Tsuga heterophylla and Picea sitchensis seedling patterns in a 3900-ha landscape in the Oregon Coast Range, USA, as a function of Landsat TM imagery, aerial photographs, digital elevation models, and stream maps. Because the models explained only moderate amounts of variability (R2 values of 0.24,0.56), we interpreted the predicted patterns as qualitative spatial trends rather than precise maps. P. sitchensis seedling patterns were tightly linked to the riparian network, with highest densities in coastal riparian areas. T. heterophylla seedlings exhibited complex patterns related to topography and overstory forest cover, and were also spatially clustered around patches of old-growth forest. We hypothesize that the old growth served as refugia for this fire-sensitive species following wildfires in the late 19th and early 20th centuries. Low levels of T. heterophylla regeneration in hardwood-dominated forests suggest that these patches may succeed to shrublands rather than to conifer forest. Predictive models of seedling patterns could be developed for other landscapes where georeferenced inventory plots, remote sensing data, digital elevation models, and climate maps are available. [source] Novel B and T cell epitopes of chicken ovomucoid (Gal d 1) induce T cell secretion of IL-6, IL-13, and IFN-,CLINICAL & EXPERIMENTAL ALLERGY, Issue 6 2001E. Holen Background Chicken ovomucoid (OM, Gal d 1) has an important role in the pathogenesis of IgE-mediated allergic reactions to hen's egg white. Objectives The purpose of this study was to clarify the mechanisms of T cell recognition of ovomucoid using intact OM and chemically modified, characterized and homogeneous solid phase synthetic peptides covering the whole molecule. Methods Eighteen overlapping peptides were prepared by solid phase F-moc polyamide peptide synthesis (SPPS), characterized and high-pressure liquid chromatography (HPLC) purified. The peptides, together with intact, denatured and oxidized OM, were used to stimulate patient-derived cell cultures for mapping T cell epitopes. Proliferation responses, T cell phenotype and cytokine secretion using peripheral blood mononuclear cells (PBMC) from eight individuals and T cell lines (TCL) derived from six hen's egg-allergic patients, were examined. In addition, intact, denatured, oxidized and deglycosylated OM, as well as the peptides solely or with their keyhole limpet haemocyanin (KLH) complexes, were tested. For locating IgE and IgG B cell epitopes, seven egg-allergic patient sera and three OM-polyclonal sera were used. Healthy non-allergic individuals were included as controls. Results Seven peptides were recognized by specific IgE, while OM-specific TCL recognized 10 peptides. Six of the OM peptides were commonly recognized both by patient S-IgE and blood-derived TCL. Among those, one novel epitope, peptide OM 61,74, had the ability to bind IgE. Another peptide, OM 101,114, was recognized by IgE and IgG sera, but not by any of the TCLs. In contrast, the peptides OM 41,56, OM 71,84, OM 131,144 and OM 171,186 were exclusively T cell epitopes with no affinity to specific antibodies. Abundant TCL secretion of IFN-,, IL-6, IL-4, IL-13, IL-10 and TNF-, in response to OM stimulation indicates the contribution of Th2 as well as Th1/Th0 CD4+ cell subsets. For allergic patients moderate amounts of IFN-,, IL-13, and high amounts of IL-6, were secreted in response to TCL stimulation by OM peptides. High amounts of IL-6 were secreted in response to all molecular forms of OM (intact-, modified-OM and the peptides 71,84 and 51,64) when TCLs from two non-allergic donors were used. Conclusions One novel B cell epitope (OM 61,74) and 10 T cell epitopes have been identified. The most reactive epitopes of the OM molecule comprise the motifs 1,14 to 71,84, the overlapping peptide-pairs OM 121,134 and OM 131,144 and peptides OM 161,174 and 171,186. Peptides OM 1,14 and 171,186 are the only ones capable of inducing IL-4 secretion. Only one peptide (OM 11,24) induces IL-10 secretion. Those peptides recognized as both T and B cell epitopes or only T cell epitopes, have the potential to induce T cell secretion of moderate to high amounts of IL-13, IFN-, and particularly IL-6. [source] | ||||||||||||||||||||||