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Selected AbstractsExperimental study on the extraction and distribution of textual domain keywordsCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 16 2008Xiangfeng Luo Abstract Domain keywords of text play a primary role in text classifying, clustering and personalized services. This paper proposes a term frequency inverse document frequency (TFIDF) based method called TDDF (TFIDF direct document frequency of domain) to extract domain keywords from multi-texts. First, we discuss the optimal parameters of TFIDF, which are used to extract textual keywords and domain keywords. Second, TDDF is proposed to extract domain keywords from multi-texts, which takes document frequency of domain into account. Finally, the distribution of domain keywords on scientific texts is studied. Experiments and applications show that TDDF is more effective than the optimal TFIDF in the extraction of domain keywords. Domain keywords accord with normal distribution on a single text after deleting the ubiquitous domain keywords. Copyright © 2008 John Wiley & Sons, Ltd. [source] Oestrogen receptor-alpha activation augments post-exercise myoblast proliferationACTA PHYSIOLOGICA, Issue 1 2010A. Thomas Abstract Aim:, Our laboratory has shown that oestrogen acts to augment myoblast (satellite cell) activation, proliferation and total number and that this may occur through an oestrogen receptor (OR)-mediated mechanism. The purpose of this study was to further investigate the mechanism of oestrogen influence on augmentation of post-exercise myoblast numbers through use of a specific OR-, agonist, propyl pyrazole triol (PPT). Methods:, Ovariectomized rats were used (n = 64) and separated into four groups: sham, oestrogen supplemented, agonist supplemented, and a combined oestrogen and agonist supplemented group. These groups were further subdivided into control (unexercised) and exercise groups. Surgical removal of white vastus and soleus muscles was performed 72 h post-exercise. Muscle samples were immunostained for the myoblast markers Pax7 and MyoD. Results:, A significant increase in total (Pax7-positive) and activated (MyoD-positive) myoblasts was found in all groups post-exercise. A further significant augmentation of total and activated myoblasts occurred in oestrogen supplemented, agonist supplemented and the combined oestrogen and agonist supplemented groups post-exercise in white vastus and soleus muscles relative to unsupplemented animals. Conclusion:, These results demonstrate that both oestrogen and the specific OR-, receptor agonist, PPT, can significantly and to similar degrees augment myoblast number and activation following exercise-induced muscle damage. This suggests that oestrogen acts through an OR-mediated mechanism to stimulate myoblast proliferation following exercise, with OR-, playing a primary role. [source] Hypotonic buffer induces meiosis and formation of anucleate cytoplasmic islands in the egg of the two-spotted cricket Gryllus bimaculatusDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 2 2003Isao Sarashina In insects, egg activation is known to occur in vivo and independently of fertilization, but its mechanisms are poorly understood. To gain understanding of these mechanisms, an attempt was made to activate the egg of Gryllus bimaculatus in vitro. It was found that meiosis resumed and was completed in unfertilized eggs treated with hypotonic buffer. Early developmental processes in activated, unfertilized eggs were investigated and compared with those in fertilized eggs. Mitosis did not progress, resulting in formation of anucleate cytoplasmic islands (pseudoenergids). Development in the activated, unfertilized eggs stopped at this stage and both yolk subdivision and cellularization did not occur. To elucidate the role of the nucleus in the developmental process to the syncytial stage in fertilized eggs, eggs were treated with aphidicolin to inhibit DNA polymerization. It was found that pseudoenergids also formed in these aphidicolin-treated fertilized eggs. These results demonstrate that pseudoenergids can increase in number independently of nuclei, suggesting that the cytoplasm rather than the nucleus plays the primary role in development to the syncytial stage in G. bimaculatus. [source] Fructose-mediated non-enzymatic glycation: sweet coupling or bad modificationDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 5 2004Casper G. Schalkwijk Abstract The Maillard reaction is a process in which reducing sugars react spontaneously with amino groups in proteins to advanced glycation endproducts (AGEs). Although an elevated level of glucose had been thought to play a primary role in the Maillard reaction, on a molecular basis, glucose is among the least reactive sugars within biological systems. The formation of AGEs is now also known to result from the action of various metabolites other than glucose, which are primarily located intracellularly and participate in the non-enzymatic glycation reaction at a much faster rate, such as fructose, trioses and dicarbonyl compounds. In this review, we considered the glycation reaction with particular attention to the potential role of fructose and fructose metabolites. The two sources for fructose are an exogenous supply from the diet and the endogenous formation from glucose through the aldose reductase pathway. Despite its ,eightfold higher reactivity, the contribution of extracellular glycation by fructose is considerably less than that by glucose, because of the low plasma concentration of fructose (5 mmol/L glucose vs 35 µmol/L fructose). Intracellularly, fructose is elevated in a number of tissues of diabetic patients in which the polyol pathway is active. In the cells of these tissues, the concentrations of fructose and glucose are of the same magnitude. Although direct evidence is not yet available, it is likely that the high reactivity of fructose and its metabolites may substantially contribute to the formation of intracellular AGEs and may contribute to alterations of cellular proteins, dysfunction of cells and, subsequently, to vascular complications. Copyright © 2004 John Wiley & Sons, Ltd. [source] Coevolution of antibiotic production and counter-resistance in soil bacteriaENVIRONMENTAL MICROBIOLOGY, Issue 3 2010Paris Laskaris Summary We present evidence for the coexistence and coevolution of antibiotic resistance and biosynthesis genes in soil bacteria. The distribution of the streptomycin (strA) and viomycin (vph) resistance genes was examined in Streptomyces isolates. strA and vph were found either within a biosynthetic gene cluster or independently. Streptomyces griseus strains possessing the streptomycin cluster formed part of a clonal complex. All S. griseus strains possessing solely strA belonged to two clades; both were closely related to the streptomycin producers. Other more distantly related S. griseus strains did not contain strA. S. griseus strains with only vph also formed two clades, but they were more distantly related to the producers and to one another. The expression of the strA gene was constitutive in a resistance-only strain whereas streptomycin producers showed peak strA expression in late log phase that correlates with the switch on of streptomycin biosynthesis. While there is evidence that antibiotics have diverse roles in nature, our data clearly support the coevolution of resistance in the presence of antibiotic biosynthetic capability within closely related soil dwelling bacteria. This reinforces the view that, for some antibiotics at least, the primary role is one of antibiosis during competition in soil for resources. [source] Autoantibodies in alcoholic liver diseaseADDICTION BIOLOGY, Issue 2 2000Ian G. McFarlane Despite many decades of research, the reasons why only a relatively small proportion of individuals who consume excessive quantities of alcohol develop clinically significant liver disease remain unknown. The association with features of autoimmune diseases, including hypergammaglobulinaemia, circulating autoantibodies, inheritance of certain immunogenetic (HLA) markers and response to corticosteroid therapy in some patients has led to a persistent impression that altered immune regulation with a relative loss of self-tolerance underlies susceptibility to the development of the more severe forms of alcoholic liver disease (alcoholic hepatitis and/or cirrhosis). However, review of the data from the numerous studies that have been conducted over the past 30 years fails to reveal sufficiently convincing evidence that autoimmunity plays a primary role in alcohol-related liver damage. In particular, most of the wide range of circulating autoantibodies that have been reported in patients are found mainly at low titres, are not confined to those with severe liver injury, and are probably more likely to be a response to the hepatic insult than causally related to liver damage. Additionally, an association with various HLA phenotypes has not been confirmed by meta-analysis. Interpretation is complicated by evidence that alcohol may have direct effects on some components of the immune system but, if there is an immunogenetic basis for alcoholic liver disease, the present evidence suggests that this might be related more to cytokine gene polymorphisms than to a predisposition to autoimmunity per se. [source] The role of mineral and organic components in phenanthrene and dibenzofuran sorption by soilEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 3 2006R. Celis Summary Improved predictions of sorption of hydrophobic organic compounds (HOCs) in soil require a better knowledge of the relative contribution of inorganic and organic soil constituents to the sorption process. In this paper, sorption of a three-ring polycyclic aromatic hydrocarbon (phenanthrene) and a three-ring heterocyclic,aromatic compound (dibenzofuran) by six agricultural soils, their clay-size fractions, and a series of single, binary, and ternary model sorbents was evaluated to elucidate the relative role of soil mineral and organic components in the retention of these two model HOCs. The sorption coefficients for phenanthrene and dibenzofuran on purified soil organic materials (Kd = 821,9080 litre kg,1) were two orders of magnitude greater than those measured on mineral model sorbents (Kd = 0,114 litre kg,1). This, along with the strong correlation between sorption and the organic C content of the soil clay fractions (r = 0.99, P < 0.01), indicated a primary role of soil organic matter in the retention of both compounds. However, weak relationships between phenanthrene and dibenzofuran sorption coefficients and the organic C content of the bulk soils and variability of Koc values among soils, clay fractions, and model sorbents (1340,21020 litre kg,1 C for phenanthrene and 1685,7620 litre kg,1 C for dibenzofuran) showed that sorption was not predictable exclusively from the organic C content of the materials. Organic matter heterogeneity and domain blockage arising from organic matter,clay interactions and associated pH shifts were identified as the most likely causes of the different organic C-normalized sorption capacities of the soils. A direct contribution from minerals to the sorption of phenanthrene and dibenzofuran by the soils studied was likely to be small. Our results suggested that suitable descriptors for the extent of organic matter,mineral interactions would help to improve current Koc -based sorption predictions and subsequently the assessment of risk associated with the presence of HOCs in soil. [source] Disruption of the gene encoding 3,-hydroxysterol ,14 -reductase (Tm7sf2) in mice does not impair cholesterol biosynthesisFEBS JOURNAL, Issue 20 2008Anna M. Bennati Tm7sf2 gene encodes 3,-hydroxysterol ,14 -reductase (C14SR, DHCR14), an endoplasmic reticulum enzyme acting on ,14 -unsaturated sterol intermediates during the conversion of lanosterol to cholesterol. The C-terminal domain of lamin B receptor, a protein of the inner nuclear membrane mainly involved in heterochromatin organization, also possesses sterol ,14 -reductase activity. The subcellular localization suggests a primary role of C14SR in cholesterol biosynthesis. To investigate the role of C14SR and lamin B receptor as 3,-hydroxysterol ,14 -reductases, Tm7sf2 knockout mice were generated and their biochemical characterization was performed. No Tm7sf2 mRNA was detected in the liver of knockout mice. Neither C14SR protein nor 3,-hydroxysterol ,14 -reductase activity were detectable in liver microsomes of Tm7sf2(,/,) mice, confirming the effectiveness of gene inactivation. C14SR protein and its enzymatic activity were about half of control levels in the liver of heterozygous mice. Normal cholesterol levels in liver membranes and in plasma indicated that, despite the lack of C14SR, Tm7sf2(,/,) mice are able to perform cholesterol biosynthesis. Lamin B receptor 3,-hydroxysterol ,14 -reductase activity determined in liver nuclei showed comparable values in wild-type and knockout mice. These results suggest that lamin B receptor, although residing in nuclear membranes, may contribute to cholesterol biosynthesis in Tm7sf2(,/,) mice. Affymetrix microarray analysis of gene expression revealed that several genes involved in cell-cycle progression are downregulated in the liver of Tm7sf2(,/,) mice, whereas genes involved in xenobiotic metabolism are upregulated. [source] Central forkhead domain of human TFIIE, plays a primary role in binding double-stranded DNA at transcription initiationGENES TO CELLS, Issue 3 2009Aki Tanaka The human general transcription factor, TFIIE, consists of two subunits, , and ,. Structural analyses indicated the presence of a forkhead motif within the central region of TFIIE,. This motif was essential for transcription and possessed a double-stranded DNA-binding activity. Protein-DNA photo-cross-linking studies indicated that TFIIE, binds within the promoter region, adjacent to the transcription initiation site where promoter melting begins at transcription initiation. Furthermore, neither TFIIE nor the other general transcription factor TFIIH, were required for basal transcription of adenovirus major late promoter artificially pre-melted at the initiation site. These data suggest a model in which TFIIE binds to a position adjacent to the initiation site via the forkhead domain, enabling TFIIH to begin opening the promoter. Here, we used systematic point mutations to further investigate the functional roles of this domain. The mutant proteins were expressed in bacteria, purified and used to examine transcription of two different forms of template, phosphorylation of the C-terminal domain of RNA polymerase II, as well as dsDNA-binding. Taken together, our results strongly demonstrated that the primary function of the forkhead region is dsDNA-binding in transcription. In addition, we identified three positively charged lysine residues which play a key role in this function. [source] Analytical and 3-D numerical modelling of Mt. Etna (Italy) volcano inflationGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 2 2005A. Bonaccorso SUMMARY Since 1993, geodetic data obtained by different techniques (GPS, EDM, SAR, levelling) have detected a consistent inflation of the Mt. Etna volcano. The inflation, culminating with the 1998,2001 strong explosive activity from summit craters and recent 2001 and 2002 flank eruptions, is interpreted in terms of magma ascent and refilling of the volcanic plumbing system and reservoirs. We have modelled the 1993,1997 EDM and GPS data by 3-D pressurized sources to infer the position and dimension of the magma reservoir. We have performed analytical inversions of the observed deformation using both spheroidal and ellipsoidal sources embedded in a homogeneous elastic half-space and by applying different inversion methods. Solutions for these types of sources show evidence of a vertically elongated magma reservoir located 6 km beneath the summit craters. The maximum elevation of topography is comparable to such depth and strong heterogeneities are inferred from seismic tomography; in order to assess their importance, further 3-D numerical models, employing source parameters extracted from analytical models, have been developed using the finite-element technique. The deformation predicted by all the models considered shows a general agreement with the 1993,1997 data, suggesting the primary role of a pressure source, while the complexities of the medium play a minor role under elastic conditions. However, major discrepancies between data and models are located in the SE sector, suggesting that sliding along potential detachment surfaces may contribute to amplify deformation during the inflation. For the first time realistic features of Mt. Etna are studied by a 3-D numerical model characterized by the topography and lateral variations of elastic structure, providing a framework for a deeper insight into the relationships between internal sources and tectonic structures. [source] Stocks and dynamics of SOC in relation to soil redistribution by water and tillage erosionGLOBAL CHANGE BIOLOGY, Issue 10 2006JIANHUI ZHANG Abstract Soil organic carbon (SOC) displaced by soil erosion is the subject of much current research and the fundamental question, whether accelerated soil erosion is a source or sink of atmospheric CO2, remains unresolved. A toposequence of terraced fields as well as a long slope was selected from hilly areas of the Sichuan Basin, China to determine effects of soil redistribution rates and processes on SOC stocks and dynamics. Soil samples for the determination of caesium-137 (137Cs), SOC, total N and soil particle size fractions were collected at 5 m intervals along a transect down the two toposequences. 137Cs data showed that along the long slope transect soil erosion occurred in upper and middle slope positions and soil deposition appeared in the lower part of the slope. Along the terraced transect, soil was lost over the upper parts of the slopes and deposition occurred towards the downslope boundary on each terrace, resulting in very abrupt changes in soil redistribution over short distances either side of terrace boundaries that run parallel with the contour on the steep slopes. These data reflect a difference in erosion process; along the long slope transect, water erosion is the dominant process, while in the terraced landscape soil distribution is mainly the result of tillage erosion. SOC inventories (mass per unit area) show a similar pattern to the 137Cs inventory, with relatively low SOC content in the erosional sites and high SOC content in depositional areas. However, in the terraced field landscape C/N ratios were highest in the depositional areas, while along the long slope transect, C/N ratios were highest in the erosional areas. When the samples are subdivided based on 137Cs-derived erosion and deposition data, it is found that the erosional areas have similar C/N ratios for both toposequences, while the C/N ratios in depositional areas are significantly different from each other. These differences are attributed to the difference in soil erosion processes; tillage erosion is mainly responsible for high-SOC inventories at depositional positions on terraced fields, whereas water erosion plays a primary role in SOC storage at depositional positions on the long slope. These data support the theory that water erosion may cause a loss of SOC due to selective removal of the most labile fraction of SOC, while on the other hand tillage erosion only transports the soil over short distances with less effect on the total SOC stock. [source] UV-Light-Driven Immobilization of Surface-Functionalized Oxide Nanocrystals onto Silicon,ADVANCED FUNCTIONAL MATERIALS, Issue 2 2007E. Fanizza Abstract TiO2 nanorods (NRs) and ,-Fe2O3 nanocrystals (NCs) passivated with unsaturated long-chain carboxylic acids, namely 10-undecylenic acid (10UDA) and oleic acid (OLEA), are covalently anchored to Si(100) at room temperature by UV-light-driven reaction of hydrogenated silicon with the carbon,carbon double bond (,CC,) moieties of the capping surfactants. The high reactivity of vinyl groups towards Si provides a general tool for attaching particles of both materials via Si,C bonds. Interestingly, TiO2 NRs were efficiently attached to silicon even when capped by OLEA. This latter finding has been explained by a photocatalytic mechanism involving the primary role of hydroxyl radicals that can be generated upon bandgap TiO2 photoexcitation with UV light. The increased oxide coverage achievable on Si opens access to further surface manipulation, as demonstrated by the possibility of depositing an additional film of Au nanoparticles onto TiO2 via TiO2 -catalyzed visible-light-driven reduction of aqueous AuCl4, ions. Extensive morphological and chemical characterization of the obtained NC-functionalized Si substrates is provided to support the effectiveness of proposed photochemical approaches. [source] A French, abridged version of the Hospitals and Hostels Practices Profile ScheduleINTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 4 2001Marc Corbičre Abstract This study aims to validate the Hospitals and Hostels Practices Profile Schedule (HHPPS) in the French version according to the statistical requirements of factor analysis and internal consistency, and to arrive at as parsimonious a version of the questionnaire as possible. As no validation of the original English instrument exists to our knowledge, the most parsimonious factor structure suggested by hypothetical constructs was used. Analyses of variance of six categories of residential settings served to underscore their points of convergence and divergence in terms of degree of autonomy allowed to patients. The following seven scales emerged from the analyses: ,activities: house rules', ,activities: morning wake-up', ,health and hygiene', ,activities: curfew', ,personal effects', ,activities: night-time surveillance' and ,meals'. These accounted for 65% of the cumulative explained variance. Of the residential settings considered, supervised apartments allowed patients the most autonomy, compared with psychiatric hospital wards, hostels, nursing homes, foster families and group homes. Aside from its primary role of measuring the degree of autonomy that residential settings allow patients, this questionnaire seems suitable for gauging the adequacy of fit between a patient's needs and available residential facilities. This should help to direct persons with severe and persistent mental disorders towards facilities better tailored to their needs. Copyright © 2001 Whurr Publishers Ltd. [source] Women's experiences with vaginal pessary useJOURNAL OF ADVANCED NURSING, Issue 11 2009Sandra Storey Abstract Title.,Women's experiences with vaginal pessary use. Aim., This paper is a report of a study of the lived experiences of women using vaginal pessaries for the treatment of urinary incontinence (UI) and/or pelvic organ prolapse. Background., The use of a vaginal pessary offers a non-surgical treatment option to provide physical support to the bladder and internal organs. As the literature asserts, a woman's choice to use a pessary is very individual and involves not only physical, but also psychological and emotional considerations. Method., Narrative inquiry was used to conduct face-to-face semi-structured interviews in 2007 with 11 postmenopausal women who accessed services from a Urogynecology Clinic in Eastern Canada. Findings., The women's stories revealed that living with a pessary is a life-changing experience and an ongoing learning process. The women's comfort level and confidence in caring for the device figured prominently in their experiences. Psychosocial support provided by the clinic nurses also played a primary role in the women's experiences. Conclusion., Women and healthcare professionals need to be aware of the personal isolation and embarrassment, and social and cultural implications that urinary incontinence may cause as well as the subjective experiences of using a pessary. With appropriate support, vaginal pessaries can provide women with the freedom to lead active, engaged and social lives. [source] The renin,angiotensin system as a primary cause of polyarteritis nodosa in ratsJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 6a 2010Barbara S. Peters Abstract Polyarteritis nodosa is a necrotizing vasculitis of medium-sized arteries of unknown origin. Hypertension is present in 30% of patients with polyarteritis nodosa. In those cases, high renin levels are thought to be secondary to renal involvement. The present study was performed to identify causal factors of polyarteritis nodosa. In cyp1a1ren-2 transgenic rats, vasculitis of medium-sized arteries resembling classical polyarteritis nodosa can be induced. In this model, oral administration of indole-3-carbinol (I3C) activates the liver-specific cyp1a1 promoter, leading to prorenin expression in a dose-dependent manner. After the first 6 weeks of chronic induction with 0.125% I3C, the mean arterial pressure reached a plateau of about 170 mmHg. Ten out of 11 I3C-treated rats, which were chronically instrumented with a telemetric device to measure blood pressure, developed polyarteritis nodosa within 10 weeks of I3C treatment. I3C alone or instrumentation alone did not cause polyarteritis nodosa. The angiotensin-converting enzyme inhibitor captopril completely prevented the development of polyarteritis nodosa, indicating that local angiotensin II generation is a pathogenetic factor in this model. The renin,angiotensin system can play a primary role in the development of polyarteritis nodosa in rats. [source] The fat child,a sign of ,bad' motherhood?JOURNAL OF COMMUNITY & APPLIED SOCIAL PSYCHOLOGY, Issue 5 2009An analysis of explanations for children's fatness on a Finnish website Abstract Children's fatness has become a central concern worldwide, Finland included. In Finland, fatness is mainly discussed from the biomedical viewpoint as a considerable health risk resulting from individual ways of life. In the case of childhood fatness, it is the parents that are mainly held responsible for its prevention and treatment. It has been widely noted that fat people are often blamed for such things as laziness and lack of self-control. As regards fat children, however, the role and possible blaming of parents has received less scholarly attention. This paper examines the ways children's fatness is explained in an anonymous Finnish Internet discussion, focusing especially on the ways parents are depicted as causing their child's fatness and as possibly blameworthy for this. A discourse analysis revealed that parents were mainly viewed as the primary cause of the child's fatness and were negatively constructed as having ,lousy' characters, being unable to create an ,adequate' emotional bond with their child, or as otherwise engaging in ,faulty' child-rearing practices. Significantly, the latter two constructions included notions similar to the psychological expert notions of parenthood. All three constructions of parents were also gendered, being either implicitly or explicitly equated with the mother. Children's fatness was also explained, and parents' primary role thus questioned or mitigated, by reference to some other factors, such as genes. These explanations, however, did not seem to hold their ground in the discussion. The occurrence and implications of these explanations is discussed. Copyright © 2009 John Wiley & Sons, Ltd. [source] Lay food and health worker involvement in community nutrition and dietetics in England: roles, responsibilities and relationship with professionalsJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 3 2008L. A. Kennedy Abstract Background, Community-based food initiatives have developed in recent years with the aim of engaging previously ,hard to reach' groups. Lay workers engaged in community nutrition activities are promoted as a cost-effective mechanism for reaching underserved groups. The main objective of the study was to explore perceptions and definitions of lay food and health worker (LFHW) helping roles within the context of National Health Service (NHS) community nutrition and dietetic services in order to define the conceptual and practical elements of this new role and examine the interface with professional roles. Methods, Interpretive qualitative inquiry; semi-structured interviews with LFHW and NHS professionals employed by community-based programmes, serving ,hard-to-reach' neighbourhoods, across England. A total sampling framework was used to capture all existing and ,fully operational' lay food initiatives in England at the commencement of fieldwork (January 2002). Findings, In total, 29 professionals and 53 LFHWs were interviewed across 15 of the 18 projects identified. Although all 15 projects shared a universal goal, to promote healthy eating, this was achieved through a limited range of approaches, characterized by a narrow, individualistic focus. Lay roles spanned three broad areas: nutrition education; health promotion; and administration and personal development. Narratives from both professionals and LFHWs indicated that the primary role for LFHWs was to encourage dietary change by translating complex messages into credible and culturally appropriate advice. Conclusions, This research confirms the emerging discipline involving lay helping within the NHS and community dietetics. The primary role of LFHWs in the 15 projects involved was to support existing NHS services to promote healthy eating amongst ,hard to reach' communities. The activities undertaken by LFHWs are strongly influenced by professionals and the NHS. Inherent to this is a fairly narrow interpretation of health, resulting in a limited range of practice. [source] Staff in services for people with intellectual disabilities: the impact of stress on attributions of challenging behaviourJOURNAL OF INTELLECTUAL DISABILITY RESEARCH, Issue 11 2005D. Rose Abstract Background There is a lack of a conceptual framework as to how stress and attribution variables interact and influence staff behaviour in response to challenging behaviour. To address this, a model is tested examining the impact of stress on attributions of challenging behaviour within Weiner's model of helping. Method A total of 107 staff working in community homes for people with intellectual disabilities completed a self-report questionnaire that measured stress, burnout, attributions, emotions, optimism and helping behaviour in response to challenging behaviour. Results Partial support was found for the role of attributions and emotions. However, although staff reported high stress levels and moderate burnout, this did not appear to relate to their reporting of thoughts and feelings regarding challenging behaviour predicted by Weiner's helping model. It was not possible to fully test the helping model, as the ,help' variable was not normally distributed. Conclusions There was little evidence to suggest that stress has a primary role in determining staff responses when examined within Weiner's model of helping. Limited support in general was offered for Weiner's helping model. Potential conceptual difficulties and clinical implications are explored and alternative models for future research are discussed. [source] Promotion of neuronal cell adhesion by members of the IgLON family occurs in the absence of either support or modification of neurite outgrowthJOURNAL OF NEUROCHEMISTRY, Issue 6 2002Christine J. McNamee Abstract The IgLONs are a family of glycosyl phosphatidyl inositol-linked cell adhesion molecules which are thought to modify neurite outgrowth and may play a role in cell,cell recognition. The family consists of LAMP, OBCAM, neurotrimin/CEPU-1 and neurotractin/kilon. In this paper we report the effect of recombinant LAMP, CEPU-1 and OBCAM, and transfected cell lines expressing these molecules, on the adhesion and outgrowth of dorsal root ganglion (DRG) and sympathetic neurones. CHO cells transfected with cDNA for CEPU-1 adhered to a recombinant CEPU-1-Fc substrate. However, DRG or sympathetic neurones only adhered to CEPU-1-Fc when presented on protein A. Although DRG and sympathetic neurones express IgLONs on their surface, both types of neurones exhibited differential adhesion to CEPU-1-Fc, LAMP-Fc and OBCAM-Fc. Neither DRG nor sympathetic neurones extended neurites on a protein A/IgLON-Fc substrate and overexpression of CEPU-1-GFP in DRG neurones also failed to stimulate neurite outgrowth on an IgLON-Fc substrate. DRG neurones adhered to and extended neurites equally on transfected and non-transfected cell lines and the recombinant proteins did not modulate the outgrowth of neurones on laminin. In contrast to previous reports we suggest that IgLONs may not have a primary role in axon guidance but may be more important for cell,cell adhesion and recognition. [source] New established melanoma cell lines: genetic and biochemical characterization of cell division cycleJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 1 2003A Vozza ABSTRACT Background Cancer might be envisaged as the result of a genetic process causing the unregulated proliferation of a given cell as well as its inability to undergo differentiation and/or apoptosis. Alterations of genes regulating cell division cycle appear to play a key role in the development of human cancer. Objective On the bases of the above considerations, we decided to establish new cell lines from human melanoma specimens, in order to analyse the molecular alterations in primary preparations of malignant cells. Results The present paper describes two new established cell lines and their genetic and biochemical features. Both the melanoma cell lines show inactivation of the cyclin-dependent kinase inhibitor gene, CDKN2A/p16INK4A, thus demostrating that this alteration occurs in primary human melanomas. No other alterations were observable when we investigated several different cell cycle genes including those encoding cyclins, cyclin-dependent kinases and cyclin-dependent kinase inhibitors. Analyses at protein level by means of immunoblotting confirmed the results obtained at the genetic level. Moreover, the inducibility of a pivotal cyclin-dependent kinase inhibitor gene, namely p21CIP1 gene, was obtained by treating the cells with histone deacetylase inhibitors, namely butyrate and phenylbutyrate. Conclusions Our results suggest a primary role of cyclin-dependent kinase inhibitor genes inactivation in the origin of human melanoma and allow the proposal of new therapeutic strategies based on the transcriptional activation of p21CIP1 gene. [source] Genetic diversity, but not hatching success, is jointly affected by postglacial colonization and isolation in the threatened frog, Rana latasteiMOLECULAR ECOLOGY, Issue 9 2007GENTILE FRANCESCO FICETOLA Abstract Both postglacial colonization and habitat fragmentation can reduce the genetic diversity of populations, which in turn can affect fitness. However, since these processes occur at different spatial and temporal scales, the consequences of either process may differ. To disentangle the relative role of isolation and postglacial colonization in determining genetic diversity and fitness, we studied microsatellite diversity of 295 individuals from 10 populations and measured the hatch rate of 218 clutches from eight populations of a threatened frog, R. latastei. The populations that were affected by fragmentation to a greater extent suffered higher embryo mortality and reduced hatch rate, while no effects of distance from glacial refugium on hatch rate were detected. Altogether, distance from glacial refugium and isolation explained > 90% of variation in genetic diversity. We found that the genetic diversity was lowest in populations both isolated and far from the glacial refugium, and that distance from refugium seems to have the primary role in determining genetic diversity. The relationship between genetic diversity and hatch rate was not significant. However, the proportion of genetic diversity lost through recent isolation had a significant, negative effect on fitness. It is possible that selection at least partially purged the negative effects of the ancestral loss of genetic diversity. [source] Organizational structures that support internal program evaluationNEW DIRECTIONS FOR EVALUATION, Issue 120 2008Michael T. Lambur This chapter explores how the structure of large complex organizations such as Cooperative Extension affects their ability to support internal evaluation of their programs and activities. Following a literature review of organizational structure and its relation to internal evaluation capacity, the chapter presents the results of interviews with 10 selected Extension evaluators. Four structures for evaluation in Extension organizations are identified: (1) a separate evaluation unit, (2) within an administrative unit, (3) within a program area, and (4) within an academic department or school. The interviews addressed the philosophy and approach to program evaluation, what evaluators do, the perceived effects of organizational structure on evaluation, and reflections on the optimal structure for program evaluation in Extension. Several conclusions are presented: the evaluation function should be associated with a high administrative level in the organization, locating the evaluation function in program units appears to be preferred, roles and responsibilities of internal evaluators need to be clearly specified, internal evaluators need to work closely with administration and management to carry out their roles effectively and to incorporate evaluation into organizational decision making, and internal evaluators often assume other roles beyond their primary role as evaluator. © Wiley Periodicals, Inc. [source] ROCK ART AND RITUAL LANDSCAPE IN CENTRAL SPAIN: THE ROCK CARVINGS OF LA HINOJOSA (CUENCA)OXFORD JOURNAL OF ARCHAEOLOGY, Issue 1 2003MARGARITA DÍAZ-ANDREU Summary. In this article the rock art carvings of La Hinojosa in central Spain are examined. Their connection to a major transit route recorded at least from the medieval period is explored, as well as their location in a valley located at the confluence of two primary river basins in the Iberian Peninsula separated by less than five kilometres. It is argued that this singularity of the landscape seems to have been perceived by the people who marked the stones. From the 17 decorated rocks recorded in La Hinojosa valley, three were exceptionally elaborately decorated. They were situated at regular intervals in the valley. The site with the greatest number of motifs, the large rock of San Bernardino, occupies a central location. This site is also exceptional because of the transformations which the rock shows throughout the day, pointing to a narrative in which cups and anthropomorphs seem to have a primary role. It is suggested that gender may have constituted one of the main guidelines of the narrative, given the apparent replacement of feminine by masculine human representations throughout the day. [source] Correlation of tracheal smooth muscle function with structure and protein expression during early development,PEDIATRIC PULMONOLOGY, Issue 5 2007Aaron B. Cullen MD Abstract With increased survival of premature infants, understanding the impact of development on airway function and structure is imperative. Airway smooth muscle plays a primary role in the modulation of airway function. The purpose of this study is to correlate the functional maturation of airway smooth muscle during the perinatal period with structural alterations at the cellular, ultrastructural, and molecular levels. Length-tension and dose-response analyses were performed on tracheal rings acquired from preterm and term newborn lambs. Subsequent structural analyses included isolated airway smooth muscle cell length, electron microscopy, and myosin heavy chain isoform expression measurements. Functionally the compliance, contractility, and agonist sensitivity of the tracheal rings matured during preterm to term development. Structurally, isolated cell lengths and electron microscopic ultrastructure were not significantly altered during perinatal development. However, expression of myosin heavy chain isoforms increased significantly across the age range analyzed, correlating with the maturational increase in smooth muscle contractility. In conclusion, the developmental alterations in tracheal function appear due, in part, to enhanced smooth muscle myosin heavy chain expression. Pediatr Pulmonol. 2007; 42:421,432. © 2007 Wiley-Liss, Inc. [source] Distribution of P2X3 -immunoreactive fibers in hairy and glabrous skin of the ratTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 6 2009Anna M.W. Taylor Abstract The skin is innervated by two populations of unmyelinated sensory fibers, the peptidergic and nonpeptidergic, which transmit nociceptive information to the central nervous system. The peptidergic population expresses neuropeptides such as substance P (SP) and calcitonin gene-related peptide (CGRP) and has both cutaneous and visceral targets. The nonpeptidergic population expresses the purinergic receptor P2X3, binds the isolectin B4 (IB4), and innervates mainly the epidermis. To date, the peptidergic nociceptor population in cutaneous tissue of the rat has been well characterized, whereas the nonpeptidergic innervation pattern has lacked an adequate description. To this aim, we used light microscopic immunocytochemistry to investigate the pattern of P2X3 -immunoreactive (-IR) fiber innervation of both hairy and glabrous skin from male Sprague-Dawley rats. Our results show extensive P2X3 -IR fibers throughout the upper and lower dermis. Thick bundles of P2X3 -IR fibers were found to run in parallel with the dermal-epidermal junction and projected multiple thin collateral axons that penetrated the epidermal layer, creating a dense network of innervation throughout the entire epidermis. The distribution of P2X3 -IR fibers in the epidermis was far more extensive than the distribution of CGRP-IR fibers. P2X3 -IR fibers also innervate hair follicles but were rarely found in close proximity to glands and blood vessels. The present results suggest a primary role for P2X3 -IR fibers in the detection of noxious stimuli in cutaneous tissue and provide an anatomical basis for future studies examining a possible functionally distinct role of nonpeptidergic nociceptors in the transmission of nociceptive signals. J. Comp. Neurol. 514:555,566, 2009. © 2009 Wiley-Liss, Inc. [source] Lessons from studies on focal segmental glomerulosclerosis: an important role for parietal epithelial cells?THE JOURNAL OF PATHOLOGY, Issue 3 2006B Smeets Abstract Glomerular diseases are caused by multiple mechanisms. Progressive glomerular injury is characterized by the development of segmental or global glomerulosclerosis independent of the nature of the underlying renal disease. Most studies on glomerular disease focus on the constituents of the filtration barrier (podocytes, glomerular basement membrane (GBM), endothelial cells) or the mesangial cells. Little attention is given to the epithelial cells lining Bowman's capsule, the so called parietal epithelial cells (PECs). This ,lack of attention' is partly explained by the presumed ,passive' function of PECs, which are large, flattened cells that cover Bowman's capsule in a single cell layer and form a barrier between the ultrafiltrate and the periglomerular interstitium, in normal glomerular physiology. A more important reason has been the lack of an established primary role for the parietal epithelium in glomerular diseases. However, in recent years, several studies have demonstrated that PECs are involved in extracapillary proliferation. In addition, PECs can become highly active, proliferating cells, expressing many growth factors, chemokines, cytokines, and their receptors. It was recently demonstrated that PECs also play a part in the development of focal segmental glomerulosclerosis (FSGS). This review summarises current knowledge of the PEC, with emphasis on the role of PECs in the development of FSGS. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] Phase-dependent and task-dependent modulation of stretch reflexes during rhythmical hand tasks in humansTHE JOURNAL OF PHYSIOLOGY, Issue 3 2005Ruiping Xia Phase-dependent and task-dependent modulation of reflexes has been extensively demonstrated in leg muscles during locomotory activity. In contrast, the modulation of reflex responses of hand muscles during rhythmic movement is poorly documented. The objective of this study was to determine whether comparable reflex modulation occurs in muscles controlling finger motions during rhythmic, fine-motor tasks akin to handwriting. Twelve healthy subjects performed two rhythmic tasks while reflexes were evoked by mechanical perturbations applied at various phases of each task. Electromyograms (EMGs) were recorded from four hand muscles, and reflexes were averaged during each task relative to the movement phase. Stretch reflexes in all four muscles were found to be modulated in amplitude with respect to the phase of the rhythmic tasks, and also to vary distinctly with the tasks being conducted. The extent and pattern of reflex modulation differed between muscles in the same task, and between tasks for the same muscle. Muscles with a primary role in each task showed a higher correlation between reflex response and background EMG than other muscles. The results suggest that the modulation patterns observed may reflect optimal strategies of central,peripheral interactions in controlling the performance of fine-motor tasks. As with comparable studies on locomotion, the phase-dependency of the stretch reflexes implies a dynamically fluctuating role of proprioceptive feedback in the control of the hand muscles. The clear task-dependency is also consistent with a dynamic interaction of sensory feedback and central programming, presumably adapted to facilitate the successful performance of the different fine-motor tasks. [source] Chromatic and spatial properties of parvocellular cells in the lateral geniculate nucleus of the marmoset (Callithrix jacchus)THE JOURNAL OF PHYSIOLOGY, Issue 1 2004Esther M. Blessing The parvocellular (PC) division of the afferent visual pathway is considered to carry neuronal signals which underlie the red,green dimension of colour vision as well as high-resolution spatial vision. In order to understand the origin of these signals, and the way in which they are combined, the responses of PC cells in dichromatic (,red,green colour-blind') and trichromatic marmosets were compared. Visual stimuli included coloured and achromatic gratings, and spatially uniform red and green lights presented at varying temporal phases and frequencies. The sensitivity of PC cells to red,green chromatic modulation was found to depend primarily on the spectral separation between the medium- and long-wavelength-sensitive cone pigments (20 or 7 nm) in the two trichromatic marmoset phenotypes studied. The temporal frequency dependence of chromatic sensitivity was consistent with centre,surround interactions. Some evidence for chromatic selectivity was seen in peripheral PC cells. The receptive field dimensions of parvocellular cells were similar in dichromatic and trichromatic animals, but the achromatic contrast sensitivity of cells was slightly higher (by about 30%) in dichromats than in trichromats. These data support the hypothesis that the primary role of the PC is to transmit high-acuity spatial signals, with red,green opponent signals appearing as an additional response dimension in trichromatic animals. [source] Endogenous isoflavones are essential for the establishment of symbiosis between soybean and Bradyrhizobium japonicumTHE PLANT JOURNAL, Issue 2 2006Senthil Subramanian Summary Legume iso/flavonoids have been implicated in the nodulation process, but questions remain as to their specific role(s), and no unequivocal evidence exists showing that these compounds are essential for nodulation. Two hypotheses suggest that the primary role of iso/flavonoids is their ability to induce rhizobial nod gene expression and/or their ability to modulate internal root auxin concentrations. The present work provides direct, genetic evidence that isoflavones are essential for nodulation of soybean roots because of their ability to induce the nodulation genes of Bradyrhizobium japonicum. Expression of isoflavone synthase (IFS), a key enzyme in the biosynthesis of isoflavones, is specifically induced by B. japonicum. When IFS was silenced using RNA interference in soybean hairy root composite plants, these plants had severely reduced nodulation. Surprisingly, pre-treatment of B. japonicum or exogenous application to the root system of either of the major soybean isoflavones, daidzein or genistein, failed to restore normal nodulation. Silencing of chalcone reductase led to very low levels of daidzein and increased levels of genistein, but did not affect nodulation, suggesting that the endogenous production of genistein was sufficient to support nodulation. Consistent with a role for isoflavones as endogenous regulators of auxin transport in soybean roots, silencing of IFS resulted in altered auxin-inducible gene expression and auxin transport. However, use of a genistein-hypersensitive B. japonicum strain or purified B. japonicum Nod signals rescued normal nodulation in IFS-silenced roots, indicating that the ability of isoflavones to modulate auxin transport is not essential to nodulation. [source] Improving predictions of the location and use of warrens in sensitive rabbit populationsANIMAL CONSERVATION, Issue 5 2009I. C. Barrio Abstract The location and use of warrens is a key factor in the population dynamics of the European rabbit Oryctolagus cuniculus L., which can influence stability and persistence in the long term. Within the species' original distribution range, its numbers have declined sharply in recent decades, which is a serious problem for the conservation of Mediterranean ecosystems. Artificial warrens are commonly used to bolster rabbit populations and the characterization of natural warrens in those areas might improve their efficiency. In this study, we use binomial generalized linear models to identify the factors associated with the location and use of warrens in a low-density area and we evaluate the effect of including the spatial structure of the data in the model. In addition, we generate a map that predicts the most suitable areas for artificial warrens. Contrary to what was expected, habitat variables are only secondary factors, and the location and use of warrens is influenced mainly by spatial factors, such as proximity to nearby warrens. Furthermore, the aggregated spatial pattern of warrens suggests that, at the local scale, for example, the hunting estate, intra-specific interactions might be playing a primary role in these low-density populations. To identify the most suitable sites for artificial warrens and, thereby, improve the efficiency of artificial warren building for conservation purposes, information about spatial structures should be included in models predicting natural warrens of European rabbits. [source] | ||||||||||||||||||||||||||||