bluuebunny/crossref_metadata_2025 huggingface dataset:
Transforming Growth Factor-α Inhibits the Intrinsic Pathway of c-Myc-Induced Apoptosis through Activation of Nuclear Factor-κB in Murine Hepatocellular Carcinomas
Authors: Cavin Lakita G. , Wang Fang , Factor Valentina M. , Kaur Swayamjot , Venkatraman Manickam , Thorgeirsson Snorri S. , Arsura Marcello
Published: September 2005

Nuclear factor-κB (NF-κB) plays an important role during liver neoplastic development through transcriptional regulation of prosurvival genes, which then counteract the death-inducing signals elicited by the host immune response. The c-Myc proto-oncogene is frequently deregulated in liver tumors. Furthermore, enforced expression of c-Myc in the liver promotes the development of hepatocellular carcinomas, a process that is accelerated by coexpression with transforming growth factor-α (TGF-α). TGF-α/c-Myc–derived hepatocellular carcinomas display reduced apoptotic levels compared with those of single c-Myc transgenic hepatocellular carcinomas, suggesting that TGF-α provides a survival advantage to c-Myc-transformed hepatocytes. Given that TGF-α/c-Myc hepatocellular carcinomas display constitutive NF-κB activity, here, we have tested the hypothesis that enforced expression of TGF-α results in constitutive NF-κB activation and enhanced cell survival using TGF-α/c-Myc–derived hepatocellular carcinoma cell lines. We show that TGF-α induces NF-κB through the phosphatidylinositol 3-kinase/Akt axis in these bitransgenic hepatocellular carcinomas. Furthermore, we found that adenovirus-mediated inhibition of NF-κB activity impairs the ability of TGF-α/c-Myc–derived tumor cells to grow in an anchorage-independent fashion due to sensitization to c-Myc-induced apoptosis. Lastly, we show that NF-κB inhibits c-Myc-induced activation of caspase-9 and caspase-3 through up-regulation of the antiapoptotic target genes Bcl-XL and X-linked inhibitor of apoptosis (XIAP). Overall, these results underscore a crucial role of NF-κB in disabling apoptotic pathways initiated by oncogenic transformation.
Components of DNA Damage Checkpoint Pathway Regulate UV Exposure–Dependent Alterations of Gene Expression of FHIT and WWOX at Chromosome Fragile Sites
Authors: Ishii Hideshi , Mimori Koshi , Inageta Taeko , Murakumo Yoshiki , Vecchione Andrea , Mori Masaki , Furukawa Yusuke
Published: September 2005

Common chromosome fragile sites are highly recombinogenic and susceptible to deletions during the development of environmental carcinogen–induced epithelial tumors. Previous studies showed that not only genetic but also epigenetic alterations in cancerous cells are involved in inactivation of the genes FHIT and WWOX at chromosome fragile sites, reported to be potential tumor suppressor genes. Here we investigated the effect of UV light on the gene expression. After exposure to UV, the mRNA and protein of the two genes in murine embryonic fibroblasts (MEF) were unstable, apparently at the G1-S phase of the cell cycle, which was consistent with nuclear run-on assay. A study of MEFs synchronized via a double thymidine block indicated that, after the exposure, the expression of Fhit and Wwox was reduced in E2f-1–deficient cells and markedly in wild-type cells, whereas the reduction was partially inhibited in Trp53-deficient cells; cells at the S phase seemed to be sensitive to exogenous FHIT, suggesting a role of the checkpoint at the G1-S phase in the stability of gene expression and a possible involvement of FHIT function at the S phase. The transfection experiment showed that the UV-induced decrease in expression was partially inhibited by transfection of kinase-dead Atr (ataxia telangiectasia mutated and Rad3 related), which is a sensor of UV-induced damage. Taken together, the present study showed that UV-induced alterations of the fragile site gene expression are involved at least partially in the checkpoint function, suggesting the role in the process of carcinogenesis after exposure to UV.
Category Deficits and Paradoxical Dissociations in Alzheimer's Disease and Herpes Simplex Encephalitis
Authors: Laws Keith R. , Sartori Giuseppe
Published: September 2005

Most studies examining category specificity are single-case studies of patients with living or nonliving deficits. Nevertheless, no explicit or agreed criteria exist for establishing category-specific deficits in single cases regarding the type of analyses, whether to compare with healthy controls, the number of tasks, or the type of tasks. We examined two groups of patients with neurological pathology frequently accompanied by impaired semantic memory (19 patients with Alzheimer's disease and 15 with Herpes Simplex Encephalitis). Category knowledge was examined using three tasks (picture naming, naming-to-description, and feature verification). Both patient groups were compared with age-and education-matched healthy controls. The profile in each patient was examined for consistency across tasks and across different analyses; however, both proved to be inconsistent. One striking finding was the presence of paradoxical dissociations (i.e., patients who were impaired for living things on one task and nonliving things on another task). The findings have significant implications for how we determine category effects and, more generally, for the methods used to document double dissociations across individual cases in this literature.
Audiovisual Integration in Patients with Visual Deficit
Authors: Frassinetti Francesca , Bolognini Nadia , Bottari Davide , Bonora Annalisa , Làdavas Elisabetta
Published: September 2005

In the present study, we investigated the possibility that bimodal audiovisual stimulation of the affected hemifield can improve perception of the visual events in the blind hemifield of hemianopic patients, as it was previously demonstrated in neglect patients. Moreover, it has been shown that “hetero-modal” and “sensory-specific” cortices are involved in cross-modal integration. Thus, the second aim of the present study was to examine whether audiovisual integration influences visual detection in patients with different cortical lesions responsible of different kinds of visual disorders. More specifically, we investigated cross-modal, audiovisual integration in patients with visual impairment due to a visual field deficit (e.g., hemianopia) or visuospatial attentional deficit (e.g., neglect) and patients with both hemianopia and neglect. Patients were asked to detect visual stimuli presented alone or in combination with auditory stimuli that could be spatially aligned or not with the visual ones. The results showed an enhancement of visual detection in cross-modal condition (spatially aligned condition) comparing to unimodal visual condition only in patients with hemianopia or neglect; by contrast, the multi-sensory integration did not occur when patients presented both deficits. These data suggest that patients with visual disorders can enormously benefit the multisensory integration. Moreover, they showed a different influence of cortical lesion on multi-sensory integration. Thus, the present results show the important adaptive meaning of multisensory integration and are very promising with respect to the possibility of recovery from visual and spatial impairments.
Load Capacity of Concrete Masonry Block Walls Strengthened with Epoxy-bonded GFRP Sheets
Authors: Al-Salloum Yousef A. , Almusallam Tarek H.
Published: September 2005

Epoxy bonding a thin layer of composite materials to the exterior surfaces of unreinforced masonry (URM) walls forces the individual brick or block elements to act as an integrated system. The high tensile strength of composite materials can be utilized to increase the shear and flexural capacity of URM walls significantly. This article presents the results of the experimental work carried out to investigate the capability of glass fiber reinforced polymer (GFRP) laminates in strengthening the concrete block walls subjected to out-of-plane and in-plane vertical and lateral stresses. A significant strength increase was observed for all strengthened specimens. Based on deformation compatibility and force equilibrium, simple design equations are presented to estimate the strength of masonry walls and their possible mode of failure. An excellent agreement between measured and predicted values of ultimate strength of wall specimens has been observed.
Mode-II Fracture in E-glass-polyester Composite
Authors: Szekrényes András , Uj József
Published: September 2005

In this work a novel beam analysis of the end-loaded split (ELS) and over-notched flexure (ONF) specimens are presented. New compliance and strain energy release rate equations are developed incorporating crack tip deformation and transverse shear analysis. The Saint Venant effect at the clamped end of the ELS specimen is also considered. Unidirectional glass-polyester specimens are manufactured and experimental (initiation and propagation) tests are performed to confirm the theoretical models. The experimental data is evaluated by means of four reduction techniques: the exact beam theory, virtual crack closure technique, compliance calibration method, and direct beam theory. It is shown that the results by the four methods agree quite closely; however, the compliance calibration method is not recommended for initiation data reduction in the case of the ONF specimen. The ELS specimens suffer from relatively large displacements. Thus, propagation tests are not possible to be performed. The ONF test seems to be a better tool to evaluate the mode-II toughness of composite materials with low flexural modulus.
Network Modeling Approach to Predict the Effect of the Reinforcement Content on the Hot Strength of Al-based Composites
Authors: Jalham Issam S.
Published: September 2005

In this investigation, the empirical formula that is used to predict the strength of the composite material has been compared to the predictions of the strength of Al-based composites by the trained artificial neural network (ANN), and trained Neuro-fuzzy network. To achieve this purpose, four schemes of evaluation have been used. The results showed that the Neuro-fuzzy network is the best tool to predict the hot deformation behavior of Al-based composites with different reinforcement contents (5, 15, and 20%) of Al2O3 particles that have an average particle size of 25 mm at different deformation conditions, since the reinforcement content and the deformation conditions have a nonlinear complex effect on the flow stress.
The P3 in ‘ecstasy’ polydrug users during response inhibition and execution
Authors: Gamma Alex , Brandeis Daniel , Brandeis Ruven , Vollenweider Franz X.
Published: September 2005

Substance abuse and associated externalizing disorders are characterized by behavioural disinhibition and low impulse control, with reduced neural inhibition postulated to be the common underlying brain mechanism. The P3 component of event-related potentials (ERPs) is a widely used neurophysiological measure thought to reflect inhibitory brain processes, but as yet has not been assessed in ecstasy users. We recorded ERPs evoked by a Continuous Performance Test (CPT) in 16 current ecstasy polydrug users and 17 controls. The CPT included conditions where a prepared motor response had to be executed (Go) or inhibited (NoGo). Both controls and ecstasy users showed normal, robust patterns of P3 anteriorization and delay in the NoGo compared to the Go condition. Ecstasy users had lower P3 amplitudes at midline electrodes and a less anterior location of NoGo P3 peaks. These effects became weaker after statistically controlling for age, educational level and lifetime cannabis use. While lower P3 amplitudes are consistent with higher levels of neural disinhibition in ecstasy polydrug users, the normal switch pattern between response execution and inhibition, and the less anterior location of the NoGo P3, do not indicate disturbed inhibitory brain mechanisms.
Disagreement, asymmetry, and liberal legitimacy
Authors: Quong Jonathan
Published: September 2005

Reasonable people disagree deeply about the nature of the good life. But reasonable people also disagree fundamentally about principles of justice. If this is true, then why does political liberalism permit the state to act on reasons of justice, but not for reasons grounded in conceptions of the good life? There appears to be an indefensible asymmetry in the way political liberalism treats disagreements about justice and disagreements about the good life. This is the asymmetry objection to political liberalism. The principal aim of this article is to show that the asymmetry objection can be refuted. This is done by drawing a distinction between two different types of reasonable disagreement that can occur between citizens. The first type is foundational disagreement. Disagreements of this type are characterized by the fact that the participants do not share any premises which can serve as a mutually acceptable standard of justification. The second type of disagreement, justificatory disagreement, occurs when participants do share premises that serve as a mutually acceptable standard of justification, but they nevertheless disagree about certain substantive conclusions. Making this distinction allows me to show why political liberalism’s asymmetric treatment of justice and the good life is both defensible and desirable.
Induction of p38- and gC1qR-dependent IL-8 expression in pulmonary fibroblasts by soluble hepatitis C core protein
Authors: Moorman Jonathan P , Fitzgerald S Matthew , Prayther Deborah C , Lee Steven A , Chi David S , Krishnaswamy Guha
Published: September 2005

Background

Recent studies suggest that HCV infection is associated with progressive declines in pulmonary function in patients with underlying pulmonary diseases such as asthma and chronic obstructive pulmonary disease. Few molecular studies have addressed the inflammatory aspects of HCV-associated pulmonary disease. Because IL-8 plays a fundamental role in reactive airway diseases, we examined IL-8 signaling in normal human lung fibroblasts (NHLF) in response to the HCV nucleocapsid core protein, a viral antigen shown to modulate intracellular signaling pathways involved in cell proliferation, apoptosis and inflammation.

Methods

NHLF were treated with HCV core protein and assayed for IL-8 expression, phosphorylation of the p38 MAPK pathway, and for the effect of p38 inhibition.

Results

Our studies demonstrate that soluble HCV core protein induces significant increases in both IL-8 mRNA and protein expression in a dose- and time-dependent manner. Treatment with HCV core led to phosphorylation of p38 MAPK, and expression of IL-8 was dependent upon p38 activation. Using TNFα as a co-stimulant, we observed additive increases in IL-8 expression. HCV core-mediated expression of IL-8 was inhibited by blocking gC1qR, a known receptor for soluble HCV core linked to MAPK signaling.

Conclusion

These studies suggest that HCV core protein can lead to enhanced p38- and gC1qR-dependent IL-8 expression. Such a pro-inflammatory role may contribute to the progressive deterioration in pulmonary function recently recognized in individuals chronically infected with HCV.
Metallothionein mediates leukocyte chemotaxis
Authors: Yin Xiuyun , Knecht David A , Lynes Michael A
Published: September 2005

Background

Metallothionein (MT) is a cysteine-rich, metal-binding protein that can be induced by a variety of agents. Modulation of MT levels has also been shown to alter specific immune functions. We have noticed that the MT genes map close to the chemokines Ccl17 and Cx3cl1. Cysteine motifs that characterize these chemokines are also found in the MT sequence suggesting that MT might also act as a chemotactic factor.

Results

In the experiments reported here, we show that immune cells migrate chemotactically in the presence of a gradient of MT. This response can be specifically blocked by two different monoclonal anti-MT antibodies. Exposure of cells to MT also leads to a rapid increase in F-actin content. Incubation of Jurkat T cells with cholera toxin or pertussis toxin completely abrogates the chemotactic response to MT. Thus MT may act via G-protein coupled receptors and through the cyclic AMP signaling pathway to initiate chemotaxis.

Conclusion

These results suggest that, under inflammatory conditions, metallothionein in the extracellular environment may support the beneficial movement of leukocytes to the site of inflammation. MT may therefore represent a "danger signal"; modifying the character of the immune response when cells sense cellular stress. Elevated metallothionein produced in the context of exposure to environmental toxicants, or as a result of chronic inflammatory disease, may alter the normal chemotactic responses that regulate leukocyte trafficking. Thus, MT synthesis may represent an important factor in immunomodulation that is associated with autoimmune disease and toxicant exposure.
A common variant of endothelial nitric oxide synthase (Glu298Asp) is associated with collateral development in patients with chronic coronary occlusions
Authors: Lamblin Nicolas , Cuilleret François J , Helbecque Nicole , Dallongeville Jean , Lablanche Jean-Marc , Amouyel Philippe , Bauters Christophe , Van Belle Eric
Published: September 2005

Background

Experimental studies support an important role for endothelial nitric oxide synthase (eNOS) in the regulation of angiogenesis. In humans, a common polymorphism exists in the eNOS gene that results in the conversion of glutamate to aspartate for codon 298. In vitro and in vivo studies have suggested a decreased NOS activity in patients with the Asp298 variant. We hypothesized that a genetic-mediated decreased eNOS activity may limit collateral development in patients with chronic coronary occlusions.

Methods

We selected 291 consecutive patients who underwent coronary angiography and who had at least one chronic (>15 days) total coronary occlusion. Collateral development was graded angiographically using two different methods: the collateral flow grade and the recipient filling grade. Genomic DNA was extracted from white blood cells and genotyping was performed using previously published techniques.

Results

Collateral development was lower in patients carrying the Asp298 variant than in Glu-Glu homozygotes (collateral flow grade: 2.64 ± 0.08 and 2.89 ± 0.08, respectively, p = 0.04; recipient filling grade: 3.00 ± 0.08 and 3.24 ± 0.07, respectively, p = 0.04). By multivariable analysis, three variables were independently associated with the collateral flow grade: female gender, smoking, and the Asp298 variant (p = 0.03) while the Asp298 variant was the sole variable independently associated with the recipient filling grade (p = 0.03).

Conclusion

Collateral development is lower in patients with the Asp298 variant. This may be explained by the decreased NOS activity in patients with the Asp298 variant. Further studies will have to determine whether increasing eNOS activity in humans is associated with coronary collateral development.
Cluster detection methods applied to the Upper Cape Cod cancer data
Authors: Ozonoff Al , Webster Thomas , Vieira Veronica , Weinberg Janice , Ozonoff David , Aschengrau Ann
Published: September 2005

Background

A variety of statistical methods have been suggested to assess the degree and/or the location of spatial clustering of disease cases. However, there is relatively little in the literature devoted to comparison and critique of different methods. Most of the available comparative studies rely on simulated data rather than real data sets.

Methods

We have chosen three methods currently used for examining spatial disease patterns: the M-statistic of Bonetti and Pagano; the Generalized Additive Model (GAM) method as applied by Webster; and Kulldorff's spatial scan statistic. We apply these statistics to analyze breast cancer data from the Upper Cape Cancer Incidence Study using three different latency assumptions.

Results

The three different latency assumptions produced three different spatial patterns of cases and controls. For 20 year latency, all three methods generally concur. However, for 15 year latency and no latency assumptions, the methods produce different results when testing for global clustering.

Conclusion

The comparative analyses of real data sets by different statistical methods provides insight into directions for further research. We suggest a research program designed around examining real data sets to guide focused investigation of relevant features using simulated data, for the purpose of understanding how to interpret statistical methods applied to epidemiological data with a spatial component.
Tumour necrosis factor-α stimulates dehydroepiandrosterone metabolism in human fibroblast-like synoviocytes: a role for nuclear factor-κB and activator protein-1 in the regulation of expression of cytochrome p450 enzyme 7b
Authors: Dulos John , Kaptein Allard , Kavelaars Annemieke , Heijnen Cobi , Boots Annemieke
Published: September 2005

Glucocorticoids have successfully been used in the treatment of rheumatoid arthritis. Data suggest that 7α-hydroxy-dehydroepiandrosterone (7α-OH-DHEA), an immunostimulating metabolite of dehydroepiandrosterone, can block glucocorticoid-induced immune suppression. Formation of 7α-OH-DHEA is catalyzed by activity of cytochrome p450 enzyme 7b (Cyp7b). Recently, we reported that tumour necrosis factor (TNF)-α, IL-1α, IL-1β and IL-17 enhance Cyp7b mRNA expression and induce a concomitant increase in the formation of 7α-OH-DHEA by fibroblast-like synoviocytes (FLS) from rheumatoid arthritis patients. The aim of this study was to elucidate which signal transduction pathway is involved in the TNF-α-mediated induction of Cyp7b activity in FLS. We studied the effects of inhibitors of different signal transduction pathways on Cyp7b activity in FLS by measuring Cyp7b mRNA expression using reverse transcription PCR and by measuring the formation of 7α-OH-DHEA. We applied SN50, an inhibitor of nuclear translocation of transcription factors (i.e. activator protein-1 [AP-1] and nuclear factor-κB [NF-κB]); PSI, a proteasome inhibitor that prevents IκB degradation and thereby NF-κB release; SP600125, a c-Jun N-terminal kinase (JNK) inhibitor; and the mitogen-activated protein kinase inhibitors PD98059 (extracellular signal-regulated kinase) and SB203580 (p38). Cyp7b is constitutively expressed in RA FLS and can be activated in response to TNF-α. SN50 and PSI prevented the TNF-α-induced increase in Cyp7b activity, whereas the mitogen-activated protein kinase inhibitors PD98059 and SB203580 had no effect. In addition, inhibition of Cyp7b mRNA expression and activity was observed with SN50, PSI and SP600125, suggesting that NF-κB and AP-1 induce Cyp7b transcription. These findings suggest that NF-κB and AP-1 are involved in the TNF-α-enhanced formation of the dehydroepiandrosterone metabolite 7α-OH-DHEA. Our results are in accordance with presence of AP-1 and NF-κB binding sites in the Cyp7b promoter.
CYP17 gene polymorphism in relation to breast cancer risk: a case-control study
Authors: Einarsdóttir Kristjana , Rylander-Rudqvist Tove , Humphreys Keith , Ahlberg Susanne , Jonasdottir Gudrun , Weiderpass Elisabete , Chia Kee Seng , Ingelman-Sundberg Magnus , Persson Ingemar , Liu Jianjun , Hall Per , Wedrén Sara
Published: September 2005

Introduction

The c.1-34T>C 5' promoter region polymorphism in cytochrome P450c17 (CYP17), a key enzyme in the biosynthesis of estrogen, has been associated with breast cancer risk, but most previous studies have been relatively small.

Methods

We genotyped 1,544 incident cases of primary breast cancer and 1,502 population controls, all postmenopausal Swedish women, for the CYP17 c.1-34T>C polymorphism and calculated odds ratios (ORs) and 95% confidence intervals (CIs) from logistic regression models.

Results

No overall association was found between CYP17 c.1-34T>C and breast cancer risk, OR 1.0 (95% CI 0.8–1.3) for the A2/A2 (CC) carriers compared to the A1/A1 (TT) carriers, regardless of histopathology. We detected an interaction between CYP17 c.1-34T>C and age at menarche (P = 0.026) but regarded that as a chance finding as no dose-response pattern was evident. Other breast cancer risk factors, including menopausal hormone use and diabetes mellitus, did not modify the overall results.

Conclusion

It is unlikely that CYP17 c.1-34T>C has a role in breast cancer etiology, overall or in combination with established non-genetic breast cancer risk factors.
Language choices and pedagogic functions in the foreign language classroom: a cross-linguistic functional analysis of teacher talk
Authors: Kim Sun Hee Ok , Elder Catherine
Published: September 2005

This article examines the language choices made by native-speaker teachers of Japanese, Korean, German and French in foreign language (FL) classrooms in New Zealand secondary schools. It explores these teachers’ patterns of alternation between English, the majority language, and the TL, using both AS-units (Analysis of Speech units), devised by Foster et al. (2000) and a multiple-category coding system entitled ‘Functional Language Alternation Analysis of Teacher Talk’ (FLAATT), developed expressly to allow a cross-linguistic comparison of the relationship between teachers’ language choices and particular pedagogic functions. Findings suggest that the participating teachers differed markedly from one another not only in the amount of TL used but also in the pedagogic functions they used most frequently and in the language (TL or English) they chose for these functions. There was a tendency by most teachers to avoid complex interactions in the TL, limiting the potential for intake and for real communication on the part of the students. Implications are drawn for research and for teacher education.
Maternal expression of the checkpoint protein BubR1 is required for synchrony of syncytial nuclear divisions and polar body arrest inDrosophila melanogaster
Authors: Pérez-Mongiovi Daniel , Malmanche Nicolas , Bousbaa Hassan , Sunkel Claudio
Published: September 2005

The spindle checkpoint is a surveillance mechanism that regulates the metaphase-anaphase transition during somatic cell division through inhibition of the APC/C ensuring proper chromosome segregation. We show that the conserved spindle checkpoint protein BubR1 is required during early embryonic development. BubR1 is maternally provided and localises to kinetochores from prophase to metaphase during syncytial divisions similarly to somatic cells. To determine BubR1 function during embryogenesis, we generated a new hypomorphic semi-viable female sterile allele. Mutant females lay eggs containing undetectable levels of BubR1 show early developmental arrest,abnormal syncytial nuclear divisions, defects in chromosome congression,premature sister chromatids separation, irregular chromosome distribution and asynchronous divisions. Nuclei in BubR1 mutant embryos do not arrest in response to spindle damage suggesting that BubR1 performs a checkpoint function during syncytial divisions. Furthermore, we find that in wild-type embryos BubR1 localises to the kinetochores of condensed polar body chromosomes. This localisation is functional because in mutant embryos, polar body chromatin undergoes cycles of condensation-decondensation with additional rounds of DNA replication. Our results suggest that BubR1 is required for normal synchrony and progression of syncytial nuclei through mitosis and to maintain the mitotic arrest of the polar body chromosomes after completion of meiosis.
Cortical localization of the Gα protein GPA-16 requires RIC-8 function duringC. elegansasymmetric cell division
Authors: Afshar Katayoun , Willard Francis S. , Colombo Kelly , Siderovski David P. , Gönczy Pierre
Published: September 2005

Understanding of the mechanisms governing spindle positioning during asymmetric division remains incomplete. During unequal division of one-cell stage C. elegans embryos, the Gα proteins GOA-1 and GPA-16 act in a partially redundant manner to generate pulling forces along astral microtubules. Previous work focused primarily on GOA-1, whereas the mechanisms by which GPA-16 participates in this process are not well understood. Here, we report that GPA-16 is present predominantly at the cortex of one-cell stage embryos. Using co-immunoprecipitation and surface plasmon resonance binding assays, we find that GPA-16 associates with RIC-8 and GPR-1/2, two proteins known to be required for pulling force generation. Using spindle severing as an assay for pulling forces, we demonstrate that inactivation of the Gβprotein GPB-1 renders GPA-16 and GOA-1 entirely redundant. This suggests that the two Gα proteins can activate the same pathway and that their dual presence is normally needed to counter Gβγ. Using nucleotide exchange assays, we establish that whereas GPR-1/2 acts as a guanine nucleotide dissociation inhibitor (GDI) for GPA-16, as it does for GOA-1,RIC-8 does not exhibit guanine nucleotide exchange factor (GEF) activity towards GPA-16, in contrast to its effect on GOA-1. We establish in addition that RIC-8 is required for cortical localization of GPA-16, whereas it is not required for that of GOA-1. Our analysis demonstrates that this requirement toward GPA-16 is distinct from the known function of RIC-8 in enabling interaction between Gα proteins and GPR-1/2, thus providing novel insight into the mechanisms of asymmetric spindle positioning.
Response of Serum C-Reactive Protein to Percutaneous Coronary Intervention Has Prognostic Value
Authors: Saleh Nawsad , Svane Bertil , Hansson Lars-Olof , Jensen Jens , Nilsson Tage , Danielsson Olle , Tornvall Per
Published: September 2005

Background: Data are sparse regarding the association between C-reactive protein (CRP) and percutaneous coronary intervention (PCI) in long-term prognosis. Previous studies have shown that PCI evokes an inflammatory response. We tested the hypothesis that the CRP response to PCI has a prognostic value.

Methods: We investigated 891 consecutive patients presenting with stable or unstable angina pectoris, with serum concentrations of cardiac troponin T ≤0.03 μg/L, who were undergoing a variety of PCIs. Serum concentrations of CRP and cardiac troponin T were determined before and the day after PCI. The mean follow-up time after PCI was 2.6 years, and the endpoint was death or nonfatal myocardial infarction.

Results: Seventy-six patients reached the endpoint (4.6% death, 3.9% nonfatal myocardial infarction), whereas 21% developed myocardial infarction during the procedure. CRP increased more than 2-fold after the procedure. Patients in the third tertile of the CRP response to PCI had an increased risk for death or nonfatal myocardial infarction in multivariate analysis.

Conclusions: Increased serum CRP in response to PCI is an independent predictor of death or nonfatal myocardial infarction independent of myocardial injury during the procedure. CRP determinations might be of value in risk stratification after PCI.
Attacking a Small Beast: Ar–CO, a Prototype for Intermolecular Forces
Authors: Havenith Martina , Schwaab Gerhard W.
Published: September 2005

The study of intermolecular forces has been of increasing interest in the past. New theoretical and experimental techniques have been developed which allow an improved understanding of these important interactions. We will give an introduction to the theoretical concepts of the description of intermolecular forces. We will tackle Ar–CO as prototype system of intermolecular forces which has been subject of intensive experimental and theoretical work in the past and has evolved to one of the most investigated intermolecular complexes. We will give here an overview over the numerous theoretical and experimental studies which have been published in the literature. A comparison between the most recent ab initio studies and the experimental work demonstrates a lack of sufficient agreement. We have carried out a semi-empirical fit of the potential energy surface to five of the seven known intermolecular modes. All modes could be reproduced within 0.4 cm using our new potential energy surface. The most significant deviation which was found in comparison to previous ab initio potentials was the appearance of a second local minimum in the potential energy surface. These results indicate a lack of a sufficient accurate theoretical description of intermolecular forces for this “little beast” which remains still a challenge for the future.
The Thermal Decomposition Kinetics of [Co(bipy)(H2O)4](C4H4O4)·4H2O
Authors: Yakuphanoglu F. , Ying Shao-Ming
Published: September 2005

The thermal decomposition kinetics of [Co(bipy)(H2O)4](C4H4O4) · 4H2O was carried out by thermogravimetry (TG) and derivate thermogravimetry (DTG) analysis at four heating rates of 5, 8, 11 and 14 °C/min in nitrogen atmosphere. TG confirmed that thermal decomposition of the compound takes place in a single step. The kinetic parameters (activation energy, frequency factor, and activation entropy) were calculated using various forms of non-isothermal methods. The activation energy obtained by the Ozawa method is in agreement with the value determined by the Coats–Redfern technique. However, a much lower activation energy was obtained by the Kissinger method.
Empirical Models of the Pair-Polarizability Trace and Anisotropy from Polarized and Depolarized Interaction-Induced Light Scattering Spectra for Gaseous Krypton
Authors: El-Kader M. S. A.
Published: September 2005

A method based on classical physics, utilizing the first few even moments of the polarized and depolarized interaction-induced light scattering spectra at room temperature to derive an empirical model for the pair-polarizability trace and anisotropy of interacting atoms, with adjustable free parameters, is described and applied to the spectra of krypton. Good agreement with ab initio and analytical results in the literature is obtained and profiles calculated with our empirical models are in excellent agreement with experiments. Theoretical calculations using these models are compared with the experimental values of the second dielectric constant and second virial Kerr coefficient for this gas. The results show excellent agreement with the experiments.
Ultraviolet Radiation Exposure, Vitamin D, and Cancer
Authors: Berwick Marianne , Kesler Denece
Published: September 2005

This paper reviews briefly the evidence for an association between various measures of UV radiation (UVR) exposure and the development of cancer. Issues such as data quality, study design, measurement variation, comparability of studies, and quantification of UV exposure in relation to skin cancer are discussed. A range of exposure, based on skin type, might be appropriate: from 5 min a day three times a week for light‐skinned individuals and 10 min a day three times a week for darker‐skinned individuals. These exposures translate into 13 h per year, for a light‐skinned individual, leading to 650 h of exposure from birth to age 50.
(Sub)‐Picosecond Spectral Evolution of Fluorescence in Photoactive Proteins Studied with a Synchroscan Streak Camera System
Authors: van Stokkum I. H. M. , Gobets B. , Gensch T. , van Mourik F. , Hellingwerf K. J. , van Grondelle R. , Kennis J. T. M.
Published: September 2005

The spectral evolution of three photoactive proteins has been investigated by measuring the fluorescence with good temporal and wavelength resolution and a high signal‐to‐noise ratio. Upon excitation at 400 nm wild‐type (wt) PYP both at neutral pH and in the low‐pH blueshifted pBdark state exhibited a strong quenching of the fluorescence, the major part of which could be described by lifetimes of about 1.7 and 7.7 ps. The remaining fluorescence decay occurred multiexponentially with lifetimes between 30 and 125 ps. Additionally, in wtPYP at neutral pH, a dynamic Stokes shift was found to occur with a time constant of about 0.25 ps. In a PYP preparation that was reconstituted with the chromophore 7‐hydroxy‐coumarin‐3‐carboxylic acid rather than the native coumaric acid, and which is therefore not capable of performing the cis‐trans‐isomerization that initiates the photocycle in wtPYP, the fluorescence was found to decay multiexponentially with lifetimes of 51 ps, 0.33 and 3.77 ns. Additionally, dynamic Stokes shifts were observed with time constants of about 0.1 and 3.5 ps. Upon comparison of the dynamics of this preparation with that of wtPYP the multiexponential decay with lifetimes of 1.7 and 7.7 ps found in wtPYP was attributed to photochemistry of the p‐coumaric‐acid chromophore. The emission from bacte‐riorhodopsin mutant D85S upon excitation at 635 nm decays biexponentially with estimated lifetimes of 5.2 and 19.1 ps. No dynamic Stokes shift was observed here. Four lifetimes were needed to describe the decay of the emission from the A* state in the green fluorescent protein. From a target analysis it was concluded that the longer lifetimes are accompanied by a decreasing probability of forming I*, which approaches zero with the longest A* lifetime of 1.5 ns. These observations may be explained by heterogeneity of A and by relaxation of A*. In all three systems studied, multiexponential decay of emission was present, suggesting that heterogeneity is a common feature of these chromophore protein complexes.
Preparation of a microporous gel polymer electrolyte with a novel preferential polymer dissolution process for Li‐ion batteries
Authors: Subramania A. , Sundaram N. T. Kalyana , Priya A. Rohini , Gangadharan R. , Vasudevan T.
Published: September 2005

A special type of polyacrylonitrile (PAN)‐based microporous polymer electrolyte was prepared by the dissolution of poly(vinyl chloride) (PVC) with a novel preferential polymer dissolution process from cast polymer films containing various amounts of PAN and PVC. PVC, dissolved from a 50 : 50 (w/w) PAN/PVC blended polymer film, had a high ionic conductivity of 5.01 × 10−3 S/cm at the ambient temperature when soaked in a 1M solution of LiClO4 in ethylene carbonate and diethyl carbonate. The amorphosity, surface morphology, and thermal stability of the microporous gel polymer electrolyte were characterized by X‐ray diffraction, scanning electron microscopy, and differential scanning calorimetry studies. Chronoamperometry and linear‐sweep voltammetry studies were performed to determine the lithium transference number and stability of the microporous polymer electrolyte membrane, respectively. Finally, a Li‐ion polymer cell was assembled with the prepared microporous gel polymer electrolyte, and its compatibility with electrode materials was studied by cyclic voltammetry. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1891–1896, 2005
Synthesis of copolymeric acrylamide/potassium acrylate hydrogels blended with poly(vinyl alcohol): Effect of crosslinking and the amount of poly(vinyl alcohol) on swelling behavior
Authors: Ali Syed Wasim , Zaidi Syed Arif Raza
Published: September 2005

A novel series of copolymeric acrylamide/potassium acrylate superabsorbents, blended with poly(vinyl alcohol), have been synthesized by using N, N′‐methylenebisacrylamide as a crosslinker and potassium persulphate (K2S2O8) as an initiator. Swelling behavior of these hydrogels in water was investigated; and on the basis of swelling properties, the diffusional behavior of water into these hydrogel systems was analyzed. It was observed that with the increase of amount of poly(vinyl alcohol) or crosslinking, the swelling of the hydrogels decreased. The hydrogel synthesized by addition of 5% poly(vinyl alcohol) and 0.25% crosslinking showed maximum swelling of 54445%. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1927–1931, 2005
Selection of a liquid for swelling the gel coating of electrodes for electrohydrodynamic pumping
Authors: Watanabe Masashi , Hara Ayako
Published: September 2005

We investigated an electrohydrodynamic pump that used a gel‐coated electrode. An organic liquid that swelled the gel was also used as the working fluid. In this study, we examined 12 liquids. The following properties were found to be preferable for the pumping: (1) the liquid can significantly swell the gel, and (2) it can flow at a high velocity when the electrode is not coated. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1996–2002, 2005
Electrostatic interactions with histone tails may bend linker DNA in chromatin
Authors: Perico Angelo , La Penna Giovanni , Arcesi Luca
Published: September 2005

Is linker DNA bent in the 30‐nm chromatin fiber at physiological conditions? We show here that electrostatic interactions between linker DNA and histone tails including salt condensation and release may bend linker DNA, thus affecting the higher order organization of chromatin. © 2005 Wiley Periodicals, Inc. Biopolymers 81: 20–28, 2006

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Conductivity and pH dual detection of growth profile of healthy and stressedListeria monocytogenes
Authors: Yang Liju , Banada Padmapriya P. , Liu Yi‐Shao , Bhunia Arun K. , Bashir Rashid
Published: September 2005

In this study, growth ofListeria monocytogenesin a low conductivity growth medium (LCGM) was simultaneously monitored by conductivity and pH measurements. Detection times obtained from the conductivity and pH growth curves were inversely related to the initial concentration ofL. monocytogenesin the medium. Linear responses were found by plotting detection times obtained from both conductivity and pH growth curves as a function of initial cell concentration in the range of 102to 107cfu/mL. The detection time was approximately 12 and 2 h for 102and 107cfu/mL of viableL. monocytogenes, respectively, using the conductivity growth curves, whereas it was approximately 1 h less using the pH growth curves. This dual detection system was used for evaluating the growth of acid‐, temperature‐, and salt‐treatedL. monocytogenesin the medium.Acid stress at pH 2 and 3 for 3 h caused approximately 12 and 4 h delay in the detection time on pH growth curves, while stress at pH 5 for 3 h did not cause a significant delay in detection time. Delay in detection times was also observed forL. monocytogenescells exposed to 45°C for more than 1 h (2 and 6 h). Exposure to 10% NaCl for 3 h did not cause visible delay in the detection time. These observations on detection times for stressedL. monocytogeneshad a consistent trend with the cell number decrease determined by surface plating method. © 2005 Wiley Periodicals, Inc.
Animating reactive motion using momentum‐based inverse kinematics
Authors: Komura Taku , Ho Edmond S. L. , Lau Rynson W. H.
Published: September 2005

Interactive generation of reactive motions for virtual humans as they are hit, pushed and pulled are very important to many applications, such as computer games. In this paper, we propose a new method to simulate reactive motions during arbitrary bipedal activities, such as standing, walking or running. It is based on momentum based inverse kinematics and motion blending. When generating the animation, the user first imports the primary motion to which the perturbation is to be applied to. According to the condition of the impact, the system selects a reactive motion from the database of pre‐captured stepping and reactive motions. It then blends the selected motion into the primary motion using momentum‐based inverse kinematics. Since the reactive motions can be edited in real‐time, the criteria for motion search can be much relaxed than previous methods, and therefore, the computational cost for motion search can be reduced. Using our method, it is possible to generate reactive motions by applying external perturbations to the characters at arbitrary moment while they are performing some actions. Copyright © 2005 John Wiley & Sons, Ltd.
Silhouette‐based motion capture for interactive VR‐systems including a rear projection screen
Authors: Thüring Sven , Herwig Jörn , Schmitt Alfred
Published: September 2005

Markerless optical motion tracking is still a challenging task; especially applied for interactive environment there real‐time is required. Tracking methods based on silhouette extraction seem to have the ability for robust real‐time detection. But most background subtraction methods are unable to adapt their background model to the fast changing unpredictable images shown on a projection screen. This restriction makes them unusable for applications involving spatially immersive displays (SID) where users are interacting in front of projection screens. This paper describes an approach to solve this challenging problem. Based on a client‐server architecture it makes use of frame buffer and screen timing information delivered by the presentation computer and standard digital cameras attached to the tracking computer. The system requires no special hardware; therefore it is comparatively cheap and furthermore fast and reliable. Sufficiently accurate algorithms for segmentation and skeleton fitting are used, allowing usage in a real‐time system. Copyright © 2005 John Wiley & Sons, Ltd.
Automatic generation of human animation based on motion programming
Authors: Zhuang Yueting , Xiao Jun , Wu Yizi , Yang Tao , Wu Fei
Published: September 2005

In motion simulations, video games and animation films, lots of interactions between characters and virtual environments are needed. Even though realistic motion data can be derived from MoCap system, motion editing and synthesis, animators must adapt these motion data to specific virtual environment manually, which is a boring and time‐consuming job. Here we propose a framework to program the movements of characters and generate navigation animations in virtual environment. Given a virtual environment, a visual user interface is provided for animators to interactively generate motion scripts, describing the characters' movements in this scene and finally used to retrieve motion clips from MoCap database and generate navigation animations automatically. This framework also provides flexible mechanism for animators to get varied resulting animations by configurable table of motion bias coefficients and interactive visual user interface. Copyright © 2005 John Wiley & Sons, Ltd.
Interactive venation‐based leaf shape modeling
Authors: Hong Sung Min , Simpson Bruce , V. G. Baranoski Gladimir
Published: September 2005

We describe a representation for tree leaves and an interactive modeling system for creating realistic close‐up images of leaf clusters. The planar outline of the leaf and the larger members of its venation system are strong factors in the recognition of plant species and as such are essential to realistic imaging. The larger veins also play a major biological role in determining the leaf surface shape and it is this role that we mimic in the shape modeling discussed in this paper. The proposed representation uses a model of a leaf consisting of a three‐dimensional skeleton formed by its larger veins and a surface membrane representing the leaf lamina that spans the void between the veins. The veins play two roles. They can be interactively modified to create the 3‐D shape of the leaf model. They also provide for realistic light and shadow effects when rendered as generalized cylinders using measured width parameters. The representation consists of two coupled data structures, a tree data structure of veins for the leaf skeleton and an unstructured triangular mesh for the leaf membrane. The skeleton is modified by the user of the modeling system, and the membrane mesh is a surface mesh that follows the skeleton shape computed using harmonic interpolation. Copyright © 2005 John Wiley & Sons, Ltd.