bluuebunny/crossref_metadata_2025 huggingface dataset:
Mutations in Ophiostoma ulmi induced by N-methyl-N′-nitro-N-nitrosoguanidine
Authors: Bernier L. , Hubbes M.
Published: January 2010

Mutations were induced in Ophiostoma ulmi, the causal agent of Dutch elm disease, by treating yeastlike cells of wild-type strains with the alkylating agent N-methyl-N′-nitro-N-nitrosoguanidine (MNNG). The induced frequency of mutation, assessed by scoring the frequency of benomyl-resistant mutants among the surviving population, was highest in treatments that left from 4 to 10% survivors. The survival rate of the cells was affected by mutagen concentration and length of exposure to MNNG, as well as by cell concentration, cell age, pH, and chemical composition of the incubation buffer. Optimal conditions for routine induction of mutants were obtained by resuspending exponentially growing cultures in phosphate buffer at pH 7.5 (2.0 × 107 cells/mL) and treating the cells with MNNG (20 μg/mL) for 90 min with agitation. The proportion of auxotrophs among the survivors increased at least 200-fold when mutagenesis was followed by nystatin enrichment. Most auxotrophs tested were sexually fertile and carried a recessive mutation at a single nuclear locus. The benomyl-resistant phenotype was dominant. Key words: Ophiostoma ulmi, Dutch elm disease, mutations, N-methyl- N′-nitro-N-nitrosoguanidine.
Somatic embryogenesis and plantlet regeneration from embryos isolated from stored seeds of Picea glauca
Authors: Tremblay F. M.
Published: January 2010

White spruce (Picea glauca) embryogenic callus was obtained using 3- to 11-year-old seeds as a source of zygotic embryos. They were cultured on half-strength Litvay's medium supplemented with 10 μM 2,4-dichlorophenoxyacetic acid, 5 μM benzylaminopurine, 1 g/L casein hydrolysate, 500 mg/L glutamine, and 1% sucrose. The frequency of induction of embryogenic callus was significantly improved by incubation at 25 °C and by a 4-h imbibition of the seeds. The yield of embryogenic callus was significantly affected by the geographic provenance of the seeds and by their number of years in storage. A significant correlation was also found between the yield of embryogénie callus and the percentage of germination of the seedlot used. Even after 11 years of storage, 40% of the zygotic embryos could produce an embryogenic callus when dissected from seeds with a high germination rate. Somatic embryos were matured after transfer onto an embryo development medium composed of the same medium but including 6% sucrose, 1 μM 2,4-dichlorophenoxyacetic acid, and 5 μM kinetin. The somatic embryos developed further under in vitro conditions and were then transplanted into soil. The somatic embryoderived plantlets established in the greenhouse were similar to control plantlets obtained from germinated seeds. Mature embryos from stored seeds were shown to constitute a valuable source for white spruce somatic embryogenesis.
Ultrastructural and cytological observations of apothecial tissues of Geopyxis carbonaria (Pezizales, Ascomycetes)
Authors: Kimbrough James W. , Gibson Jack L.
Published: January 2010

Cytological observations are made on apothecial tissues of Geopyxis carbonaria, using transmission electron microscopy. Characteristic features of both the medullary and ectal excipula are examined. Changes in ascus apex and wall structures are examined during ascus ontogeny, especially in relation to operculum position and structure. Ultrastructure of septum configuration is observed and compared in the excipulum, ascogenous hyphae, paraphyses, and at the base of young asci. Ascosporogenesis is observed from the ascus mother cell stage and initial spore delimitation until secondary wall formation. The cytological and ultrastructural observations on this species are discussed in relation to their possible taxonomic or phylogenetic value. Key words: ascosporogenesis, Discomycetes, ascospore ultrastructure, septal ultrastructure, cytochemistry.
Permineralized fruits and seeds from the Princeton chert (Middle Eocene) of British Columbia: Vitaceae
Authors: Cevallos-Ferriz Sergio R. S. , Stockey Ruth A.
Published: January 2010

Four permineralized vitaceous seeds are described from the Middle Eocene Princeton chert, Allenby Formation, British Columbia. Three distinct types of ruminate perchalazal seeds are recognized, one is described as a new species Ampelocissus similkameenensis Cevallos-Ferriz et Stockey sp.nov., while the remaining seeds are referred to as type 1 and type 2 seeds. Five integumentary zones are recognized in each seed: zone 1 is an outer zone of thin-walled rectangular to polyhedral cells; zone 2 is a zone of thick-walled sclereids; zone 3 is a zone of cells with spiral thickenings; zone 4 is a zone of rectangular thin-walled cells (when preserved); and zone 5 is a zone of tangentially elongated thin-walled cells with dark contents. The chalaza in seeds of A. similkameenensis and the type 1 seed has three distinct zones, while in the type 2 seed it contains cells similar to integumentary zone 2. These Princeton seeds illustrate that structural features of Eocene Vitaceae include characters unlike those of extant taxa. This information contributes to our knowledge of anatomical structure within the group as a whole and underscores the need for review of both fossil and extant Vitaceae. Paucity of vitaceous seeds in the Princeton chert compared to the large number of preserved aquatic and semiaquatic remains suggests that they represent plants that grew in a nearby environment. Abrasion of the integument suggests that like extant seeds, they may have been dropped after passing through the gut of a bird.
In vitro development of penetration structures in the rice blast fungus Magnaporthe grisea
Authors: Bourett Timothy M. , Howard Richard J.
Published: January 2010

The development of appressoria, penetration pegs, and infection hyphalike structures of Magnaporthe grisea on a cellophane substratum were studied using light and electron microscopy of freeze-substituted specimens. Developing, hyaline appressoria contained numerous membrane cisternae and cytoplasmic vesicles. These vesicles were concentrated near the substratum where the cell wall was very thin and then absent. Vesicles and cisternae were not present in appressoria during melanization. The discrete melanin layer contained a heretofore undescribed microfibrillar component that did not label with wheat germ agglutinin. A bilayered pore wall overlay was deposited over the appressorium pore just prior to formation of a penetration peg. The innermost of these layers and the wall of the peg both labeled with wheat germ agglutinin and concanavalin A, and appeared continuous. The mature penetration peg was uniform in width, about 7 μm in length, and contained predominantly putative cytoskeletal elements. Within the cellophane substratum, lateral branching from the distal end of the peg gave rise to a group of cells that resembled infection hyphae.
Caractérisation ultrastructurale d'une résistance induite par un éliciteur d'origine fongique, chez un cultivar sensible de Piment
Authors: Coulomb C. , Coulomb P. J. , Saimmaime I. , Lizzi Y. , Polian C.
Published: January 2010

Elicitation of a sensitive sweet pepper (Capsicum annuum) cultivar roots by immersion in the culture medium of Trichoderma album induces resistance in leaves infected by Phytophthora capsici. In infected tissues, host cells are intact and develop wall formations that look like typical wall appositions, but differ from them by the presence of a substance of cytoplasmic origin, which is phagocytized and degraded, conferring a lytic function and unusual dynamics to these structures. The involvement of the endoplasmic reticulum and peroxysomes in eventual detoxification processes is discussed. The resistance induced by this elicitor seems to be programmed by the establishment of a reactive physiological state, which produces the defense response.
Impact d'un traitement par le cycloheximide sur la reprise du cycle et sur les teneurs en protéines du bourgeon cotylédonaire du Pois réactivé par décapitation
Authors: Nougarède Arlette , Rondet Pierre , Landré Pierre , Saint-Côme Robert
Published: January 2010

Following ablation of the main stem (decapitation), the mean nuclear protein content of the Pisum cotyledonary bud apical cells increased 35% as early as the 6th hour, just when a massive entry into the S phase was registered, and reached a maximum, with a 157% increase, at the 39th hour, when the mitotic activity was also at its highest. The ratio nuclear protein/nuclear DNA content was then multiplied by 1.8 in comparison with the ratio observed in the G0–1 noncycling nuclei of the inhibited cotyledonary bud. In the bud treated with cycloheximide, the mean nuclear protein content slowly increased following decapitation, but remained greatly inferior to that of the controls. A slight entry into the S phase was noticed at the 24th hour and the mean nuclear protein content, then maximal, increased 32% in comparison with the inhibited buds. In the control buds, the mean protoplasmic proteins content increased 116% at the 39th hour (maximal value), whereas it increased only 25% in the treated buds. Following treatment with cycloheximide, the entry into the S phase was postponed and of low amplitude. However, the recycling nuclei were able to divide. An increase in the mean nuclear and cytoplasmic protein content was a prerequisite if the entry into the S phase of G0–1, nuclei was not to be postponed.
A PRINCIPLE COMPONENT ANALYSIS — NUMERICAL TAXONOMY APPROACH FOR EXPORT PERFORMANCE ASSESSMENT: THE CASE OF IRANIAN CHEMICAL UNITS
Authors: AZADEH A. , ATAEI G. H.
Published: January 2010

This paper presents an integrated approach for assessment of export performance based on principal component analysis (PCA) and Numerical Taxonomy (NT). The integrated assessment is influenced by shaping factors such as export value, production value, export growth, R&D expenditure and value added. Iranian chemical industries are selected as a case study according to the format of International Standard for Industrial Classification (ISIC) for a five-year period. The modeling approach of this paper could be used for analyzing other sectors and countries. This study shows how total export efficiency is obtained through the proposed approach whereas previous studies consider conventional productivity approach by a single indicator.
EXCHANGE RATE PASS-THROUGH IN ASEAN: IMPLICATIONS FOR THE PROSPECTS OF MONETARY INTEGRATION IN THE REGION
Authors: CORTINHAS CARLOS
Published: January 2010

This paper investigates, for the first time, the degree of exchange rate pass-through to domestic prices in all five founding members of ASEAN. For this purpose, a three-variable-recursive VAR model was applied that uses the Choleski decomposition method along the distribution chain of pricing, using data for the period 1968 to 2001.

The results show that a strong case for entering a currency union can be made for the cases of Singapore, Malaysia and Thailand, as in these countries there appears to be the case of exchange rate disconnect. A case for common currency can also be made for Indonesia but for entirely different reasons. For this country, an independent monetary policy is a clear source of shock to the economy and therefore a currency union would tend to eliminate them. Finally, a weaker case for a common currency can be made for the Philippines as evidence of some exchange rate pass-through to inflation was found but not to import prices.
DECRIMINALIZATION POLICY AND MARIJUANA SMOKING PREVALENCE: A LOOK AT THE LITERATURE
Authors: DAMRONGPLASIT KANNIKA , HSIAO CHENG
Published: January 2010

This paper reviews the literature on the impact of marijuana decriminalization policy on marijuana smoking prevalence. Due to mixed findings in the existing studies, we attempt to find a common basis to explain the different results across papers. The main purpose is to provide a coherent background as to what outcomes may be expected from certain type of data, econometric models, and explanatory variables. If possible, we also try to provide the explanation as to why certain results are found.
POLICY REFORMS AND AGRICULTURAL EXPORTS IN NIGERIA: AN EMPIRICAL ANALYSIS
Authors: OMOTOR DOUGLASON GODWIN , ORUBU CHRISTOPHER O. , INONI EMMANUEL
Published: January 2010

The role of agriculture in the process of growth and development arises mainly from its linkages with other sectors of an economy. The agricultural sector in developing countries in recent times has recorded secular declines in terms of its contribution to export earning and domestic consumption. This observation is associated with policy inertia among other factors. The Structural Adjustment Programme adopted in Nigeria in the 1980s, is one policy shift aimed at boosting agricultural production. This article aims at empirically verifying the effects of policy reform on agricultural exports in Nigeria by estimating a simple impact assessment model using a slope-dummy method. The estimates among others indicate that agricultural export is significantly influenced by domestic consumption and economic liberalization. The findings suggest that policy reforms on agricultural productivity should go beyond liberalization of the economy.
FOREIGN OWNERSHIP AND EXPORTS IN VIETNAMESE MANUFACTURING
Authors: NGOC PHAN MINH , RAMSTETTER ERIC D.
Published: January 2010

This paper analyzes exports of multinational corporations (MNCs) in Vietnamese manufacturing, highlighting the disproportionately large contribution of heavily-foreign MNCs with foreign ownership shares of 90% or more. The exports of heavily-foreign manufacturing MNCs are substantial and concentrated in apparel, footwear, and electric machinery-related industries. Export propensities also tend to be markedly higher in heavily-foreign MNCs than in other MNCs, and these differences generally persist after controlling for the effects industry affiliation, firm size, vintage, and capital intensity. There is a large variation in the relationship between ownership shares and export propensities among industries and years, however.
MANAGING EXCHANGE RATE VOLATILITY: A COMPARATIVE COUNTERFACTUAL ANALYSIS OF SINGAPORE, 1994–2003
Authors: WILSON PETER , NG HENRY SHANG REN
Published: January 2010

This paper looks at how Singapore's exchange rate regime has coped with exchange rate volatility, by comparing the performance of Singapore's actual regime in minimizing the volatility of the nominal effective exchange rate (NEER) and the bilateral rate against the US dollar with some counterfactual regimes and the corresponding performance of eight other East Asian countries. In contrast to previous counterfactual exercises, we apply a more disaggregated methodology for the trade weights, a larger number of trade partners and ARCH/GARCH techniques to capture the time-varying characteristics of volatility. Our findings confirm that Singapore's managed floating exchange rate system has delivered relatively low currency volatility. Although there are gains in volatility reduction for all countries in the sample from the adoption of either a unilateral or a common basket peg, particularly post-Asian crisis, these gains are relatively low for Singapore, largely because of low actual volatility. There are additional gains for non-dollar peggers from stabilizing intra-east Asian exchange rates against the dollar if they were to adopt a basket peg, especially post-crisis, but the gains for Singapore are again relatively modest. Finally, the conclusion from previous counterfactual studies that there is little difference between a unilateral basket peg and a common basket peg in terms of stability reduction is confirmed.
Assessing the Role of Knowledge Management in Adding Value: Moving Towards a Comprehensive Framework
Authors: Ibrahim Fahmi , Edgar David , Reid Vivien
Published: January 2010

Researchers and practitioners have emphasised the need for advances in knowledge management (KM) research to better understand how organisations add value from their KM practices. Thus, a comprehensive framework, rooted in two main theoretical streams of KM practices, objectivist and practice-based perspective, is proposed. We believe this explains how KM practices add value, and will assist organisations to obtain a more accurate picture of their KM practices, the factors that influence KM implementation, and how KM can be measured. The framework also serves as a means to identify how well KM practices meet organisational strategies. This paper begins with a review of different KM perspectives and then reports the findings of qualitative in-depth interviews with UK car manufacturers. The results indicate that most organisations adopt different types of KM practices, with the findings revealing that top management commitment, strategy, IT, people involvement and organisational culture were the factors that most influenced KM implementation. In conclusion, the paper advocates an integrated view of KM perspectives and mechanisms for KM practice in UK car manufacturing.
How to Tie Everyday Work to Strategy
Authors: Kennedy Mary Lee , Stergios Malgorzata (Gosia)
Published: January 2010

The paper describes how Harvard Business School's Knowledge and Library Services (KLS) leveraged the collective knowledge of its employees in formulating, implementing, and evaluating strategy. The organisation was faced with major, disruptive changes in its environment and needed the diverse knowledge and full engagement of all employees to make a series of strategic shifts. The shifts included integrating KLS products and services with the Harvard Business School research and course development process, developing global scope in information resources and expertise, and trading its role as the guardian of books and buildings for the organiser of the School's priority information assets. In order to achieve that, KLS launched the Environmental Scan Program, relying on employees' insights aggregated through social tagging, trend analysis and internal prediction markets tracking emerging trends. KLS also created processes for the collective assessment of strategy and a faster way of turning ideas into new products and services. The paper concludes with an assessment of the approach, pointing to a difficult balance between emergent and collective dimensions of strategy process with its formal, structured facets.
PPCI Algorithm for Mining Temporal Association Rules in Large Databases
Authors: Pandey Anjana , Pardasani K. R.
Published: January 2010

In this paper an attempt has been made to develop a progressive partitioning and counting inference approach for mining association rules in temporal databases. A temporal database like a sales database is a set of transactions where each transaction T is a set of items in which each item contains an individual exhibition period. The existing models of association rule mining have problems in handling transactions due to a lack of consideration of the exhibition period of each individual item and lack of an equitable support counting basis for each item. As a remedy to this problem we propose an innovative algorithm PPCI that combines progressive partition approach with counting inference method to discover association rules in a temporal database. The basic idea of PPCI is to first segment the database into sub-databases in such a way that items in each sub-database will have either a common starting time or a common ending time. Then for each sub-database, PPCI progressively filters 1-itemset with a cumulative filtering threshold based on vital partitioning characteristics. Algorithm PPCI is also designed to employ a filtering threshold in each partition to prune out those cumulatively infrequent 1-itemsets early and it also uses counting inference approach to minimise as much as possible the number of pattern support counts performed when extracting frequent patterns. Explicitly the execution time of PPCI in order of magnitude is smaller than those required by the schemes which are directly extended from existing methods.
Chronic kidney disease induced in mice by reversible unilateral ureteral obstruction is dependent on genetic background
Authors: Puri Tipu S. , Shakaib Mohammed I. , Chang Anthony , Mathew Liby , Olayinka Oladunni , Minto Andrew W. M. , Sarav Menaka , Hack Bradley K. , Quigg Richard J.
Published: January 2010

Chronic kidney disease (CKD) begins with renal injury; the progression thereafter depends upon a number of factors, including genetic background. Unilateral ureteral obstruction (UUO) is a well-described model of renal fibrosis and as such is considered a model of CKD. We used an improved reversible unilateral ureteral obstruction (rUUO) model in mice to study the strain dependence of development of CKD after obstruction-mediated injury. C57BL/6 mice developed CKD after reversal of three or more days of ureteral obstruction as assessed by blood urea nitrogen (BUN) measurements (>40 mg/dl). In contrast, BALB/c mice were resistant to CKD with up to 10 days ureteral obstruction. During rUUO, C57BL/6 mice exhibited pronounced inflammatory and intrinsic proliferative cellular responses, disruption of renal architecture, and ultimately fibrosis. By comparison, BALB/c mice had more controlled and measured extrinsic and intrinsic responses to injury with a return to normal within several weeks after release of ureteral obstruction. Our findings provide a model that allows investigation of the genetic basis of events during recovery from injury that contribute to the development of CKD.
Reward-Associated Gamma Oscillations in Ventral Striatum Are Regionally Differentiated and Modulate Local Firing Activity
Authors: Kalenscher Tobias , Lansink Carien S. , Lankelma Jan V. , Pennartz Cyriel M. A.
Published: January 2010

Oscillations of local field potentials (LFPs) in the gamma range are found in many brain regions and are supposed to support the temporal organization of cognitive, perceptual, and motor functions. Even though gamma oscillations have also been observed in ventral striatum, one of the brain's most important structures for motivated behavior and reward processing, their specific function during ongoing behavior is unknown. Using a movable tetrode array, we recorded LFPs and activity of neural ensembles in the ventral striatum of rats performing a reward-collection task. Rats were running along a triangle track and in each round collected one of three different types of rewards. The gamma power of LFPs on subsets of tetrodes was modulated by reward-site visits, discriminated between reward types, between baitedness of reward locations and was different before versus after arrival at a reward site. Many single units in ventral striatum phase-locked their discharge pattern to the gamma oscillations of the LFPs. Phase-locking occurred more often in reward-related than in reward-unrelated neurons and LFPs. A substantial number of simultaneously recorded LFPs correlated poorly with each other in terms of gamma rhythmicity, indicating that the expression of gamma activity was heterogeneous and regionally differentiated. The orchestration of LFPs and single-unit activity by way of gamma rhythmicity sheds light on the functional architecture of the ventral striatum and the temporal coordination of ventral striatal activity for modulating downstream areas and regulating synaptic plasticity.
Interplay Between the Inspiratory and Postural Functions of the Human Parasternal Intercostal Muscles
Authors: Hudson Anna L. , Butler Jane E. , Gandevia Simon C. , De Troyer Andre
Published: January 2010

The parasternal intercostal muscles are obligatory inspiratory muscles. To test the hypothesis that they are also involved in trunk rotation and to assess the effect of any postural role on inspiratory drive to the muscles, intramuscular electromyographic (EMG) recordings were made from the parasternal intercostals on the right side in six healthy subjects during resting breathing in a neutral posture (“neutral breaths”), during an isometric axial rotation effort of the trunk to the right (“ipsilateral rotation”) or left (“contralateral rotation”), and during resting breathing with the trunk rotated. The parasternal intercostals were commonly active during ipsilateral rotation but were consistently silent during contralateral rotation. In addition, with ipsilateral rotation, peak parasternal inspiratory activity was 201 ± 19% (mean ± SE) of the peak inspiratory activity in neutral breaths ( P < 0.001), and activity commenced earlier relative to the onset of inspiratory flow. These changes resulted from an increase in the discharge frequency of motor units (14.3 ± 0.3 vs. 11.0 ± 0.3 Hz; P < 0.001) and the recruitment of new motor units. The majority of units that discharged during ipsilateral rotation were also active in inspiration. However, with contralateral rotation, parasternal inspiratory activity was delayed relative to the onset of inspiratory flow, and peak activity was reduced to 72 ± 4% of that in neutral breaths ( P < 0.001). This decrease resulted from a decrease in the inspiratory discharge frequency of units (10.5 ± 0.2 vs. 12.0 ± 0.2 Hz; P < 0.001) and the derecruitment of units. These observations confirm that in addition to an inspiratory function, the parasternal intercostal muscles have a postural function. Furthermore the postural and inspiratory drives depolarize the same motoneurons, and the postural contraction of the muscles alters their output during inspiration in a direction-dependent manner.
Ex Utero Intrapartum Treatment for Fetal Oropharyngeal Cyst
Authors: Ayres Allen W. , Pugh Suzanne K.
Published: January 2010

Background. A prenatally diagnosed fetal anomaly that could compromise the fetal airway at delivery can be managed safely with the ex utero intrapartum treatment (EXIT) procedure. Case. A 26‐year‐old healthy primigravida was diagnosed during her midtrimester anatomic ultrasound survey with a fetal oropharyngeal cystic structure located at the base of the tongue. The neonatal airway was successfully secured intrapartum using the EXIT procedure. Conclusion. Maintenance of fetoplacental circulation until the fetal airway is secured has been described for a multitude of fetal anomalies including cystic hygroma and teratoma. The literature also recounts its use for the reversal of tracheal plugging for congenital diaphragmatic hernia. A multidisciplinary approach to the antenatal and intrapartum care is essential for the successful management of these cases.
Budding ofTaenia crassicepsCysticerci In Vitro Is Promoted by Crowding in Addition to Hormonal, Stress, and Energy-Related Signals
Authors: Ostoa-Saloma Pedro , Ostoa-Jacobo Pedro , Esquivel-Velázquez Marcela , Bazúa Silvana , Larralde Carlos
Published: January 2010

Taenia crassicepscysticerci (cysts) reproduce by budding. The cysts' production of buds was measured in vitro to explore parasite and environmental-related factors involved in the extreme individual variation in parasite loads of inbred mice. Cysts were placed in in vitro culture for 10 days at initial parasite densities of 1, 5, 10 cysts/well in 1 ml of RPMI Medium 1640 without serum. Results showed that there is considerable intrinsic initial variation among inoculated cysts in their production of buds and that increasing parasite density (crowding) stimulates the overall production of buds and recruit into budding most of the cysts. Identical cultures were then subjected to various treatments such as heating and exposure to peroxide to induce stress, or to 17ß-estradiol, insulin, glucose, or insulin+glucose to supplement putatively limiting hormonal and energy resources. All treatments increased budding but the parasites' strong budding response to crowding alone overshadows the other treatments.
Bile Acid Reflux Contributes to Development of Esophageal Adenocarcinoma via Activation of Phosphatidylinositol-Specific Phospholipase Cγ2 and NADPH Oxidase NOX5-S
Authors: Hong Jie , Behar Jose , Wands Jack , Resnick Murray , Wang Li Juan , DeLellis Ronald A. , Lambeth David , Cao Weibiao
Published: January 2010

Gastroesophageal reflux disease complicated by Barrett's esophagus (BE) is a major risk factor for esophageal adenocarcinoma (EA). However, the mechanisms of the progression from BE to EA are not fully understood. Besides acid reflux, bile acid reflux may also play an important role in the progression from BE to EA. In this study, we examined the role of phosphatidylinositol-specific phospholipase C (PI-PLC) and a novel NADPH oxidase NOX5-S in bile acid–induced increase in cell proliferation. We found that taurodeoxycholic acid (TDCA) significantly increased NOX5-S expression, hydrogen peroxide (H2O2) production, and cell proliferation in EA cells. The TDCA-induced increase in cell proliferation was significantly reduced by U73122, an inhibitor of PI-PLC. PI-PLCβ1, PI-PLCβ3, PI-PLCβ4, PI-PLCγ1, and PI-PLCγ2, but not PI-PLCβ2 and PI-PLCδ1, were detectable in FLO cells by Western blot analysis. Knockdown of PI-PLCγ2 or extracellular signal-regulated kinase (ERK) 2 mitogen-activated protein (MAP) kinase with small interfering RNAs (siRNA) significantly decreased TDCA-induced NOX5-S expression, H2O2 production, and cell proliferation. In contrast, knockdown of PI-PLCβ1, PI-PLCβ3, PI-PLCβ4, PI-PLCγ1, or ERK1 MAP kinase had no significant effect. TDCA significantly increased ERK2 phosphorylation, an increase that was reduced by U73122 or PI-PLCγ2 siRNA. We conclude that TDCA-induced increase in NOX5-S expression and cell proliferation may depend on sequential activation of PI-PLCγ2 and ERK2 MAP kinase in EA cells. It is possible that bile acid reflux present in patients with BE may increase reactive oxygen species production and cell proliferation via activation of PI-PLCγ2, ERK2 MAP kinase, and NADPH oxidase NOX5-S, thereby contributing to the development of EA. Cancer Res; 70(3); 1247–55
Proapoptotic Kinase MST2 Coordinates Signaling Crosstalk between RASSF1A, Raf-1, and Akt
Authors: Romano David , Matallanas David , Weitsman Gregory , Preisinger Christian , Ng Tony , Kolch Walter
Published: January 2010

Mammalian MST kinases function in stress-induced apoptosis to limit tumor progression. However, there is limited understanding about MST2 control by key regulators of cell division and survival. Raf-1 binds and inhibits MST2 kinase, whereas dissociation from Raf-1 and binding to tumor suppressor protein RASSF1A activates MST2. Akt phosphorylates MST2 in response to mitogens, oncogenic Ras, or depletion of tumor suppressor phosphatase and tensin homologue deleted on chromosome 10. We identified T117 and T384 as Akt phosphorylation sites in MST2. Mutation of these sites inhibited MST2 binding to Raf-1 kinase but enhanced binding to tumor suppressor RASSF1A, accentuating downstream c-Jun NH2-terminal kinase and p38 mitogen-activated protein kinase signaling and promoting apoptosis. We determined that MST2 phosphorylation by Akt limits MST2 activity in two ways: first, by blocking its binding to RASSF1A and by promoting its association into the Raf-1 inhibitory complex, and second, by preventing homodimerization of MST2, which is needed for its activation. Dissociation of the Raf-1–MST2 complex promoted mitogenic signaling and coordinately licensed apoptotic risk. Using Ras effector domain mutants, we found that Akt is essential to prevent MST2 activation after mitogenic stimulation. Our findings elucidate how MST2 serves as a hub to integrate biological outputs of the Raf-1 and Akt pathways. Cancer Res; 70(3); 1195–203
The Six-Nucleotide Deletion/Insertion Variant in the CASP8 Promoter Region Is Inversely Associated with Risk of Squamous Cell Carcinoma of the Head and Neck
Authors: Li Chunying , Lu Jiachun , Liu Zhensheng , Wang Li-E. , Zhao Hui , El-Naggar Adel K. , Sturgis Erich M. , Wei Qingyi
Published: January 2010

Caspase 8 (CASP8) is an apoptosis-related cysteine peptidase involved in the death receptor pathway and likely in the mitochondrial pathway. A CASP8 promoter region six-nucleotide deletion/insertion (−652 6N ins/del) variant and a coding region D302H polymorphism are reportedly important in cancer development, but no reported study has assessed the associations of these genetic variations with risk of head and neck cancer. In a hospital-based study of non-Hispanic whites, we genotyped CASP8 −652 6N del and 302H variants in 1,023 patients with squamous cell carcinoma of the head and neck (SCCHN) and 1,052 cancer-free controls. Crude and adjusted odds ratios (OR) and 95% confidence intervals (CI) were estimated using unconditional logistic regression models. The CASP8 −652 6N del variant genotypes or haplotypes were inversely associated with SCCHN risk (adjusted OR, 0.70; 95% CI, 0.57-0.85 for the ins/del + del/del genotypes compared with the ins/ins genotype; adjusted OR, 0.73; 95% CI, 0.55-0.97 for the del-D haplotype compared with the ins-D haplotype). Furthermore, the number of the CASP8 −652 6N del (but not 302H) variant allele tended to correlate with increased levels of camptothecin-induced p53-mediated apoptosis in T lymphocytes from 170 cancer-free controls. We concluded that the CASP8 −652 6N del variant allele may contribute to the risk of developing SCCHN in non-Hispanic white populations. Further validation by population-based case-control studies and rigorous mechanistic studies is warranted. Cancer Prev Res; 3(2); 246–53
Estimating the Attributable Fraction for Cancer: A Meta-analysis of Nevi and Melanoma
Authors: Olsen Catherine M. , Carroll Heidi J. , Whiteman David C.
Published: January 2010

Epidemiologic research has shown convincingly that certain phenotypic attributes are associated with increased relative risks of melanoma. Although such findings have intrinsic utility, there have been few attempts to translate such knowledge into estimates of disease burden suitable for framing public health policy. We aimed to estimate the population attributable fraction (PAF) for melanoma associated with melanocytic nevi using relative risk estimates derived from a systematic review and meta-analysis. We identified eligible studies using citation databases, followed by manual review of retrieved references. Of 49 studies identified, 25 and 23, respectively, were included in meta-analyses of atypical and common nevi. For people with ≥1 atypical nevi, the summary relative risk was 3.63 (95% confidence interval, 2.85-4.62), with a PAF of 0.25. The relative risk increased by 1.017 (95% confidence interval, 1.014-1.020) for each common nevus; however, significant heterogeneity in risk estimates was observed. We estimated that 42% of melanomas were attributable to having ≥25 common nevi (PAF 25-49 nevi = 0.15; PAF ≥50 nevi = 0.27), whereas PAFs for low nevus counts were modest (PAF 0-10 nevi = 0.04; PAF 11-24 nevi = 0.07). We modeled PAF under scenarios of varying nevus prevalence; the highest melanoma burden was always among those with high nevus counts (PAF range of 0.31-0.62 for ≥25 common nevi). Patients with ≥25 common nevi and/or ≥1 atypical nevi are a high-risk group, which might be targeted for identification, screening, and education. This work is the necessary first step in designing targeted preventive strategies for melanoma, which must now be overlaid with information about cost and utility. Cancer Prev Res; 3(2); 233–45
The Effectiveness of Chemoprevention Agents Is Underestimated When Lesion Sizes Are Rounded
Authors: Taylor Thomas H. , Armstrong William B. , Meyskens Frank L.
Published: January 2010

Change in the area of premalignant lesions is an end point in estimating the efficacy of chemopreventive agents. When examiners round measurements of lesion length and width, they introduce variability, which perturbs the relative percent change in lesion area and, consequently, the percent of subjects showing a clinical response. We use simulations to illustrate the resulting bias when the agent under test is effective in reducing lesion area. We simulated 500 oral leukoplakia lesions per run, with 2,500 runs at each of five levels of agent effectiveness, namely, true relative percent reduction in area of 25%, 45%, 50%, 55%, and 75%. Realistic values of lesion lengths and widths were generated randomly and then rounded to the nearest multiple of five. The product is the distribution of mean relative percent change in lesion area and the corresponding percent of subjects showing a clinical response. Even the fifth percentile of the distribution of mean relative percent change in lesion area consistently underestimated the true value, by about 6 percentage points. The percent showing a clinical response was underestimated by 50%, 37%, and 11% for true values of reduction in lesion area of 50%, 55%, and 75%, respectively. This could easily double the required sample size for a modest phase II study. We suggest that it is cost-effective to train observers of lesion length and width to eschew rounding of measurements in the chemoprevention setting. Cancer Prev Res; 3(2); 136–9
Sleep Quality, Mood, Alertness and Their Variability in CKD and ESRD
Authors: Roumelioti Maria-Eleni , Argyropoulos Christos , Buysse Daniel J. , Nayar Harry , Weisbord Steven D. , Unruh Mark L.
Published: January 2010

Background/Aims: Little is known about the association of chronic kidney disease (CKD) with sleep quality, mood, and alertness. In this report, we assessed these symptoms among patients with advanced CKD (stages 4–5) and those with end-stage renal disease (ESRD) and compared them to healthy controls without known kidney disease. Methods: Patients were recruited from local dialysis units, outpatient nephrology clinics and the Thomas E. Starzl Transplant Institute. Healthy control subjects matched for age, gender and race were drawn from an archival database. Daily symptoms of sleep quality, mood, and alertness were assessed by visual analogue scales of the Pittsburgh Sleep Diary. Health-related quality of life was assessed by the Short Form-36 instrument. Results: Sixty-nine dialysis patients and 23patients with advanced CKD demonstrated worse scores in sleep quality, mood, and alertness (p < 0.001) than controls. In adjusted analyses, European-American race, dialysis dependency, younger age, and physical performance SF-36 components were significantly associated with poor sleep quality, mood and alertness (p < 0.05). The dialysis population demonstrated higher day-to-day variability in scores than either the advanced CKD patients or the controls. Conclusion: Advanced CKD and dialysis dependency are associated with impaired and highly variable sleep quality, mood, and alertness.
Collective Memory in a Global Age
Authors: Misztal Barbara A.
Published: January 2010

This article argues that attempts to conceptualize the memory boom in amnesic societies have resulted in a clash between two theoretical stands: the approach which stresses the significance of remembering and the perspective which insists on the value of forgetting. It asserts that neither the value of memory nor the value of forgetting can be taken for granted and argues that any search for possible resolutions to the dialectical relationship between remembering and forgetting should be taken in the interest of cultivating a relationship with the past that enhances societal well-being in the present. Such reasoning leads us to judge the value of cosmopolitan memory in terms of its capacity to shape post-nationalist solidaristic political communities. The acceptance of the need to judge the act of putting the past in the service of the present requires us to question the contrasting projects of cosmopolitan citizenship: one claiming that remembering is vital for sustaining plurality and diversity of a global citizenship, and the other that stresses the importance of forgetting for the emergence of the politics of a global citizenship. After presenting contrasting views on the importance of memory for the development of cosmopolitan citizenship, the article searches for an approach to memory which is better suited to projects that aim to ensure post-nationalistic solidarity and human rights while protecting cultural rights, minority rights and personal identity.
Social Bases of American Patriotism
Authors: Ishio Yoshito
Published: January 2010

Based on a 2004 national survey data set, this article examines the effects of sociodemographic variables on American patriotism. This article demonstrates the usefulness of the generalized group dominance perspective in explaining the effects of some sociodemographic variables on patriotism. Whether socially hierarchical structures are based on race/ethnicity, religion, age or socioeconomic class, members of socially dominant groups are more emotionally attached to their country than are socially subordinate groups. However, the socialization perspective is applicable in explaining a negative effect of advanced education on patriotism. American academia may socialize students to internalize values and norms that question patriotism.
The impact of structural empowerment on individual well-being and performance: Taking agent preferences, self-efficacy and operational constraints into account
Authors: Biron Michal , Bamberger Peter
Published: January 2010

We integrate psychological and socio-structural perspectives on empowerment by examining: a) the impact of actual structural empowerment initiatives (as opposed to perceptions of such empowering acts) aimed at enhancing employee influence over which tasks to perform (as opposed to how to perform them) on employee well-being and performance, b) the degree to which self-efficacy mediates these effects, and c) the extent to which, by applying such initiatives more selectively, performance-related empowerment effects may be amplified. Results of a simulation-based experiment indicate that while granting decision latitude over which tasks to perform has beneficial effects on both individual performance and well-being, self-efficacy partially mediates the effects only on the latter. Results also indicate that the direct performance-related effects of such interventions may be further increased without any significant decline in employee well-being to the extent that such structural empowerment is applied more selectively and offered as a performance-based incentive.
Self-doubters, strugglers, storytellers, surfers and others: Images of self-identities in organization studies
Authors: Alvesson Mats
Published: January 2010

This article provides an overview of the key images of identity in organizations found in the research literature. Image refers to the overall idea or conceptualization, capturing how researchers relate to — and shape — a phenomenon. Seven images are suggested: self-doubters, strugglers, surfers, storytellers, strategists, stencils and soldiers. These refer to how the individual is metaphorically understood in terms of identity, that is, how the researcher (research text) captures the individual producing a sense of self. The article aims to facilitate orientation — or encourage productive confusion — within the field, encourage reflexivity and sharpen analytic choices through awareness of options for how to conceptualize self-identity constructions.
Involvement of Cot/Tp12 in Bone Loss during Periodontitis
Authors: Ohnishi T. , Okamoto A. , Kakimoto K. , Bandow K. , Chiba N. , Matsuguchi T.
Published: January 2010

Periodontitis causes resorption of alveolar bone, in which RANKL induces osteoclastogenesis. The binding of lipopolysaccharide to Toll-like receptors causes phosphorylation of Cot/Tp12 to activate the MAPK cascade. Previous in vitro studies showed that Cot/Tp12 was essential for the induction of RANKL expression by lipopolysaccharide. In this study, we examined whether Cot/Tp12 deficiency reduced the progression of alveolar bone loss and osteoclastogenesis during experimental periodontitis. We found that the extent of alveolar bone loss and osteoclastogenesis induced by ligature-induced periodontitis was decreased in Cot/Tp12-deficient mice. In addition, reduction of RANKL expression was observed in periodontal tissues of Cot/Tp12-deficient mice with experimental periodontitis. Furthermore, we found that Cot/Tp12 was involved in the induction of TNF-α mRNA expression in gingiva of mice with experimental periodontitis. Our observations suggested that Cot/Tp12 is essential for the progression of alveolar bone loss and osteoclastogenesis in periodontal tissue during experimental periodontitis mediated through increased RANKL expression.
Media power during humanitarian interventions: Is Eastern Europe any different from the West?
Authors: Balabanova Ekaterina
Published: January 2010

The role of the media in foreign policymaking has been the subject of significant academic enquiry, particularly in response to the so-called ‘CNN effect’, but this work has mostly focused on prominent Western nations (particularly the United States). This article enlarges the debate by adding a comparative and post-communist perspective. Taking the Kosovo conflict as a case study, it analyses the role of the media in foreign policy in Bulgaria and Britain. Through the application of Robinson’s policy— media interaction model, the article argues that the Bulgarian press did not have any substantial impact on the government’s position on the Kosovo conflict because it framed its reports in a neutral way. The British press/foreign policy relationship discloses a clear case of media support for governmental policy. The findings raise questions about the validity of certain claims about the media—policy relationship in former socialist countries. The article identifies limitations to models based on Western media systems and suggests that their construction is often based on certain cultural assumptions and hence very much context bound.
MIDLOC: Introducing the Militarized Interstate Dispute Location dataset
Authors: Braithwaite Alex
Published: January 2010

The Militarized Interstate Dispute Location (MIDLOC) dataset addresses a significant lacuna in the empirical literature on the geography of interstate conflict: the dearth of location-level data. This dataset provides details of the geographic location of Militarized Interstate Dispute (MID) onsets between 1816 and 2001. These data on locations are available at both the dispute-level (for 1816—2001) and the incident-level (for 1993—2001). This article briefly identifies the motivation behind this data-collection project, details some of the coding procedures followed in assembling the MIDLOC dataset, and then offers some mapped visualizations of the variance in this dataset across time. These maps are designed, in part, to stimulate additional hypothesis derivation in work on the geography of conflict. The data are then employed to offer a geographic assessment of the proposition that democracies tend to conduct the majority of their conflicts on their opponents’ territories. The article then concludes with a discussion of some additional potential applications of the MIDLOC dataset.
Trade networks and the Kantian peace
Authors: Dorussen Han , Ward Hugh
Published: January 2010

Classical-liberal arguments about the pacifying effects of international trade are revisited, and it is argued that they consistently refer to the ability of trade to provide ‘connections’ between people and to create a perceived ‘global community’. Dependency and openness are commonly used to test for any pacifying effects of trade in the current literature, but these measures fail to capture some of the classical liberals’ key insights. Several network measures are introduced in order to give natural expression to and to develop the classical-liberal view that trade linkages reduce interstate conflict. These measures applied to trade flows are incorporated in the Russett & Oneal triangulating-peace model. The main results are that trade networks are indeed pacifying in that both direct and indirect trade linkages matter, and as the global trade network has become more dense over time, the importance of indirect links by way of specific third countries has declined, and the general embeddedness of state dyads in the trade network has become more relevant. These findings suggest that the period since World War II has seen progressive realization of the classical-liberal ideal of a security community of trading states.