bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of Controlled Weft Yarn Tension of a Single Nozzle Air-Jet Loom on the Physical Properties of the Fabric
Authors: Nosraty Hooshang , Jeddi Ali A. A. , Kabganian Mansour , nejad Firouz Bakhtiari
Published: January 2007

Control technology is being applied in different industries including textiles. The use of open loop control in dying machines and closed loop control in the let-off motion mechanism of looms are conventional. In this study, a weft yarn tension controller was implemented in a single nozzle air-jet loom for controlling the weft yarn tension variations during weft insertion. The effective parameters on weft yarn tension were introduced by studying the weft yarn equation of motion. Experimental results show that the mechanical brake force has the major effect on weft yarn tension. Thus, the required actuator was designed on the basis of the mechanical brake being controlled by a stepper motor. The PID (proportional + integral + derivative) controller was used to control weft yarn tension. The fabric samples were woven with and without controlled weft yarn tension and their physical properties were measured. The results show that control of the weft yarn tension decreased the coefficient of variation (CV%) of the physical properties of the fabric considerably.
Effect of Liquid Ammonia on the Fine Structure of Linen Fabrics
Authors: Dornyi Barbara , Csiszár Emília , Somlai Csiszár , Sajó István
Published: January 2007

It has recently been shown that liquid ammonia treatment (water-based process) is very effective in improving the wrinkle recovery, dimensional stability, and resistance to abrasion of the all-linen fabrics. In this study the changes in the fine structure were characterized by measuring the crystallinity and sorption properties of the linen fabrics. In addition, the effect of liquid ammonia on the surface properties of the linen fibers was investigated. X-ray analysis showed that liquid ammonia treatment did not significantly affect the ratio of crystalline and amorphous regions, but a partial recrystallization occurred in the crystalline part, resulting in mixed cellulose I and III lattices in the linen substrates. Although the moisture regain and iodine sorption capacity of the treated linen substrates increased, water retention values, however, were decreased significantly by the intracrystalline swelling treatment.
Cut Resistance of High-strength Yarns
Authors: Shin Hyung-Seop , Erlich David C. , Simons Jeffrey W. , Shockey Donald A.
Published: January 2007

The cut resistance of three high-strength yarns under tension-shear loading conditions was measured by pressing a knife blade transversely at a constant rate against a yarn gripped at its ends. The load-deflection relation and the energy required to cut through the yarn were determined for Kevlar (aramid), Spectra (polyethylene), and Zylon (polybenzobisoxazole, or PBO). The cut energy and strain to initiate cutting were highest for Zylon, least for Kevlar, and depended on the slicing angle, the sharpness of the blade, and the pre-tension in the yarn. The dependencies are explained by changes in failure mode of the fibers within the yarn. The test provides input needed for computational simulations of ballistic response of fabrics to sharp fragments and should be useful in designing slash-resistant gloves and clothing.
Autoxidation of Spin Finishes
Authors: Fok Wing Y. , Hild Debra N. , Petrick Lauren M. , Obendorf S. Kay
Published: January 2007

Spin finishes, including lubricants, emulsifiers, antistatic agents, and wetting agents are used to facilitate the manufacturing and processing of textiles. Autoxidation of ten spin finish components was studied by subjecting them to air and heat over time. Chemical changes were observed visually and evaluated using UV/Vis spectroscopy, viscosity measurements, and Fourier Transform infrared (FTIR) spectroscopy. Yellowing occurred for HCO-16, TMP, wetting agent, coconut oil ethoxylate, and coconut oil. Changes in solubility were observed for wetting agent. Significant changes in viscosity were measured for CO-16, HCO-25, anti-static agent, and wetting agent. Finally, changes in FTIR spectral ratios were observed for CO-25, HCO-16, CO-16, and antistatic agent. Chemical changes observed were consistent with autoxidation of spin finish components.
Free Vibration Analysis of Laminated Composite Rectangular Plate Using Finite Element Method
Authors: Pandit M. K. , Haldar S. , Mukhopadhyay M.
Published: January 2007

A nine-noded isoparametric plate-bending element has been used for the analysis of free undamped vibration of isotropic and fiber reinforced laminated composite plates. The effect of shear deformation has been incorporated in the formulation by considering the first-order shear deformation theory for the analysis. An effective mass lumping scheme with rotary inertia has been recommended. Two types of mass lumping schemes have been formed. In one lumping scheme rotary inertia has also been introduced. Numerical examples of isotropic and composite rectangular plates having different fiber orientations angles, thickness ratios, and aspect ratio have been solved. Examples of plates having internal cutout and uniformly distributed mass on the plates have also been studied. The results obtained have been compared with the available published literature. The present results are very close to the analytical solutions. Few examples have been presented as new results.
Suicide attempt with clopidogrel
Authors: Kocabay G , Okçular I , Akkaya V , Güler Kerim
Published: January 2007

We report the case of a 49-year-old male who took an overdose of 1650 mg of clopidogrel with suicidal intend. The patient developed abnormalities of platelet aggregation, but never developed symptoms. Clopidogrel is a commonly prescribed drug. Reports of overdose of clopidogrel were very rarely reported in the literature.
Olanzapine overdose is associated with acute muscle toxicity
Authors: Waring W S , Wrate J , Bateman D N
Published: January 2007

Olanzapine is an atypical antipsychotic that is reported to cause myopathy and raised creatine kinase (CK) levels. The prevalence and severity of acute myopathy after deliberate olanzapine ingestion are unclear. Therefore, we reviewed casenotes from 64 consecutive patients admitted to our institution after olanzapine overdose. Overall, serum CK was higher than five times the upper limit of normal in 17% of patients. The prevalence of raised CK values was positively correlated with the stated quantity of olanzapine ingested, suggesting a dose-dependent relationship for acute muscle toxicity. There was an apparent delay of 12 hours or more between olanzapine ingestion and the occurrence of maximum CK. Despite the high prevalence of acute muscle toxicity after olanzapine ingestion, none of the patients developed renal failure.
The (co-)production of public uncertainty: UK scientific advice on mobile phone health risks
Authors: Stilgoe Jack
Published: January 2007

UK scientific advice on the possible health risks of mobile phones has embraced (or seems to be embracing) broader engagement with interested non-experts. This paper explains the context of lost credibility that made such a development necessary, and the implications of greater engagement for the construction (and expert control) of “public concern.” I narrate how scientific advice matured from an approach based on compliance with guidelines to a style of “public science” in which issues such as trust and democracy were intertwined with scientific risk assessment. This paper develops existing conceptions of the “public understanding of science” with an explanation based around the co-production of scientific and social order. Using a narrative drawn from a series of in-depth interviews with scientists and policymakers, I explain how expert reformulation of the state of scientific uncertainty within a public controversy reveals constructions of “The Public,” and the desired extent of their engagement. Constructions of the public changed at the same time as a construction of uncertainty as solely an expert concern was molded into a state of politically workable public uncertainty. This paper demonstrates how publics can be constructed as instruments of credible policymaking, and suggests the potential for public alienation if non-experts feel they have not been fairly represented.
Re-examining medical modernization: framing the public in Finnish biomedical research policy
Authors: Tupasela Aaro
Published: January 2007

Despite recent evidence that suggests that knowledge production within the medical community is increasingly based on knowledge-making coalitions or what some have called the co-production of knowledge, there remains a strong expert led policy agenda in many countries in relation to human genome research. This article reports on the role of experts in defining the scope of discussion in relation to the biomedical use of human tissue sample collections or biobanks in Finland using the case of the Genome Information Center. It is argued that the rhetorical strategies should not be understood simply as subversive tactics, but rather as ways of engaging the public within particular contexts of creating commercial expectations and visions which are easier to negotiate from a policy perspective.
Telecommunications and Development
Authors: Kumar Keval J. , Thomas Amos O.
Published: January 2007

Until the mid-1990s the ownership of a telephone in India was considered a luxury, not a consumer item. The waiting period for a landline could extend from five to 10 years. Even in 1996, for instance, people were waiting for a telephone after having paid a hefty amount as an application deposit for three to five years. Today in many states companies are competing to gain customers and there is no waiting list. Mobile telephone services have become so cheap now that subscriptions have outpaced fixed line connections. In 2005 and 2006 on average 4.5 million new mobile subscribers were added every month. The rapid spurt in tele-density has been exceeded only by China. This article will offer a political economic analysis of the dramatic growth of the cellular telephone industry during the last decades in India and China, and the public policy on deregulation that has driven this growth. In India the liberalization of telecommunications was ushered in the early 1990s by the Congress regime; the nationalist BJP regime further liberalized the industry. The article will also discuss the ‘mobile divide’ in the country, and between the urban and the rural sectors, and how this divide has had an impact on economic development. Some experiments in taking cellular telephony to the rural poor will be described. Finally, the article will ex-amine the uses and gratifications provided by cellular telephony, especially among the Indian youth.
Modal Active Vibration Control of a Rotor Using Piezoelectric Stack Actuators
Authors: Simões Ricardo C. , Steffen Valder , Der Hagopian Johan , Mahfoud Jarir
Published: January 2007

This work deals with active vibration control of a rotating machine in both steady state and transient motion. Two stacks of piezoelectric ceramic orthogonally arranged in a plane localized at one of the bearings were used as the control actuators, using a modal control strategy. The optimal controller LQR was used to calculate the control gain, working together with an LQE observer that estimates the modal state. Simulation carried out on FEM model suggested the feasibility of the control strategy, and experimental tests using a physical test rig show good agreement with the numerical results, and confirm the efficiency of the strategy.
Solutions of TS Fuzzy Model Based Time-Delay Dynamic Systems via Chebyshev Series Approach
Authors: Hsu Ming-Ren , Chou Jyh-Horng
Published: January 2007

A shifted Chebyshev series approach for solve the Takagi-Sugeno (TS) fuzzy model based time-delay dynamic equations (TSFMTDE) is developed in this article. The new method simplifies the procedure of solving the TSFMTDE into the solution of a system of recursive formulae involving only matrix algebra. An algorithm based on these recursive formulae, and including only straightforward algebraic computation is also proposed in this article. The new approach proposed is non-iterative, non-differential, non-integral, straightforward, and well-adapted to computer implementation. Two numerical examples are provided. The first shows that the proposed method based on the shifted Chebyshev series may yield close-to-exact solutions. The second (a nonlinear mass-spring-damper mechanical time-delay system with a fuzzy parallel-distributed-compensation controller) demonstrates the application of the proposed approach.
Development and Confirmatory Factor Analysis of the Community Norms of Child Neglect Scale
Authors: Goodvin Rebecca , Johnson David R. , Hardy Sam A. , Graef Michelle I. , Chambers Jeff M.
Published: January 2007

This article describes the development of the Community Norms of Child Neglect Scale (CNCNS), a new measure of perceptions of child neglect, for use in community samples. The CNCNS differentiates among four subtypes of neglect (failure to provide for basic needs, lack of supervision, emotional neglect, and educational neglect). Scenarios ranging in seriousness for each subtype were presented to a large community sample (N = 3,809). Confirmatory factor analyses indicated that a four-factor model provided a better fit to the data than did a model specifying only one overall neglect factor, suggesting this sample distinguished among the four subtypes of neglect. The authors tested measurement equivalence across individuals who work with children and lay community respondents and across rural and urban respondents, with results indicating a very similar structure across these groups. These initial reliability and validity data suggest that the CNCNS may be of use in comparing perceptions of child neglect among individuals and across communities.
Measuring the Risk of Physical Neglect in a Population-Based Sample
Authors: Theodore Adrea , Runyan Desmond , Chang Jen Jen
Published: January 2007

Child neglect accounts for the majority of officially substantiated cases of child maltreatment in this country, although population-based data are lacking. This study estimates the number of children at risk for specific subtypes of physical neglect, using results of an anonymous telephone survey administered to 1,435 mothers of children ages 0 to 17 years in North and South Carolina. Children were considered “at risk for neglect” from lack of enough food, lack of access to medical care when needed, and inadequate supervision. Demographic factors were significantly related to the outcomes of interest, including lower family income with lack of enough food and access to medical care. There was little overlap in children at risk for the different subtypes of neglect. Maternal self-report data can be used to improve researchers’ understanding of children at risk for neglect and to explore gaps in knowledge that might be amenable to intervention and prevention efforts.
Grand design(er)s: David Moore, natural theology and the Royal Botanic Gardens in Glasnevin, Dublin, 1838-1879
Authors: Johnson Nuala C.
Published: January 2007

Geographers have increasingly been investigating the role of space in the regulation and constitution of a range of scientific discourses from historical studies of natural history societies and zoological gardens to analyses of contemporary biotechnology industries. It is abundantly clear that geographical location and the spatial relationships underpinning such institutions form more than the material stage on which scientific activity takes place. These socially produced spaces themselves, and their internal and external connectivities, play an important role in the establishment and warranting of knowledge claims to specific interpretations of the natural world. Moreover, historically institutions such as botanical gardens not only displayed prevalent systems of taxonomic regulation; they also became sites for the investigation of order in the natural world. This paper investigates the relationship between David Moore's role as curator of Dublin's botanical garden and his delivery of an anti-evolution lecture in Belfast in 1874. For Moore, the structuring of the scientific garden and the botanical discourse attending plant life there revealed the workings of a beneficent designer and thus was a material expression of a natural theology. The classifying of plants into families, the orderly fashioning of the beds, the display of exotics in the hothouses all facilitated a particular reading of designed nature which confirmed his commitment to the existence of a divine designer, and this reading of nature was popularly translated in his Belfast lecture.
Visions of urban mobility: the Westway, London, England
Authors: Robertson Susan
Published: January 2007

This paper explores issues of urban architecture and geography through an interpretation of built form. More specifically, it attends to the urban landscapes of mobility of the elevated highway, showing how landscape and environment frame ideas and practices of movement. The concept of limited-access highways in the city could be considered as the epitome of modernity, reflecting the ever-increasing speed of everyday life and the distancing of individuals from communities. Separation from contact with the landscape and its effect on space-time relationships creates a new spatiality. The elevated highway project opens up the possibility of a completely new perception of the city, from above and at speed. The Westway, opened in 1970, is a two-and-a-half-mile long elevated highway linking the centre of London, England, with the west-of-England route to Oxford. The paper treats the space of the Westway in two particular ways: first as a modernist marker, symbolic of prevailing national urban aspirations; secondly as material form, through considering the Westway as machinic entity and as cinematic experience. Through this combination I argue that reading landscape as text is insufficient in the analysis of built form; other frameworks are necessary. In particular, this paper seeks to understand architectural space and form through a closer connection of body to space and form in both the kinaesthetic and imaginary senses.
Turning theatre into law, and other spaces of politics
Authors: Pratt Geraldine , Johnston Caleb
Published: January 2007

We assess Practicing Democracy, a play created by Headlines Theatre in Vancouver, Canada, which was the first attempt to deploy Augusto Boal's legislative theatre in North America. The goal of this project was to use forum theatre to generate creative solutions to the dangers created by provincial government cuts to social welfare, and to work with local government to turn some of these recommendations into new local government laws. This goal was not attained, although the report produced by Headlines Theatre may have supported other local initiatives. We examine the ways in which local politicians and planners maintained the distinction between expert and amateur, so as to undermine the credibility of public input. A bureaucratic process of classification and abstraction also inhibited the recommendations from being turned into law, and reinstated the expertise of politicians and bureaucrats. We balance this assessment with a reading of spaces that are excessive to this rational calculation: the city as a concrete site of embodied, creative spatial disruptions; and theatre as a pedagogical public sphere.
Collaborative film-making as process, method and text in mental health research
Authors: Parr Hester
Published: January 2007

This paper explores how film-making can assist as part of the development of sensitive and participative methodologies appropriate to accessing the worlds of people with severe and enduring mental health problems. It discusses how the film-making process can also act as a text that holds valuable data about the impact of the arts on mental health, and facilitates a range of mutually beneficial outcomes for those collaborating across usual academic/community divides. This agenda contributes to a consideration of the role of the arts in participative social geographies of mental health, and critically expands recent discussions about uses of video and film in a visual discipline.
The autoclavable semirigid thoracoscope: the way forward in pleural disease?
Authors: Munavvar M. , Khan M. A. I. , Edwards J. , Waqaruddin Z. , Mills J.
Published: January 2007

Medical thoracoscopy is a valuable tool in the investigation and management of pleural disease. It has considerable advantages over conventional blind pleural biopsy and video-assisted thoracoscopic surgery. Despite this, the practice of this technique in the UK is limited. Most operators use the rigid thoracoscope, which may be an unfamiliar instrument to respiratory physicians. A semirigid thoracoscope is available but its use has not been possible in the UK as it requires sterilisation with ethylene oxide, which is not approved in this country. The present authors describe herein their experience with the first ever autoclavable semirigid thoracoscope.

Medical thoracoscopy using the new instrument was performed in 56 patients between June 2004 and May 2006. All patients had been referred with a unilateral pleural effusion of unknown aetiology, where blind pleural aspiration had failed to yield an answer. Diagnostic samples were taken and talc poudrage performed where appropriate.

The instrument was easy to handle and excellent views were obtained. Histologically adequate biopsy samples were obtained in 54 patients. The combination of clinical features, computed tomography findings and thoracoscopic biopsy enabled a definite diagnosis in 49 (90.7%) of these patients. There were no complications.

The autoclavable semirigid thoracoscope has immense potential in the diagnosis and management of pleural disease. Its diagnostic yield in pleural disease is comparable to the conventional rigid thoracoscope. It is similar in design to the fibreoptic bronchoscope and respiratory physicians should be able to adapt to its use easily. It is also compatible with existing video processors and light sources available in most endoscopy suites. The fact that this instrument is autoclavable should open the field for its use in the UK as well as in other countries.
Safety and tolerability of bosentan in idiopathic pulmonary fibrosis: an open label study
Authors: Günther A. , Enke B. , Markart P. , Hammerl P. , Morr H. , Behr J. , Stähler G. , Seeger W. , Grimminger F. , Leconte I. , Roux S. , Ghofrani H-A.
Published: January 2007

Idiopathic pulmonary fibrosis (IPF) is a fatal disease for which no effective treatment exists. In the present study, 12 IPF patients underwent analysis of gas exchange properties using the multiple inert gas elimination technique on day 1 before and after the administration of 125 mg bosentan, a dual endothelin antagonist. Following this, patients received chronic administration for 12 weeks (62.5 mgb.i.d.in week 1, 125 mgb.i.d.thereafter). The primary objective was to determine the effect of bosentan on gas exchange (day 1) and on oxygen saturation and minute ventilation (week 2).

With one exception, where redistribution of total pulmonary blood flow from normal ventilation/perfusion (V′/Q′) areas (93% before, 72% after bosentan) to lowV′/Q′ areas (0% before, 22.2% after) was encountered, no patient showed any change in gas exchange (mean±sdshunt flow (% of cardiac output) 8.5±3.4% before, 6.1±2.3% after bosentan; day 1) or oxygen saturation and minute ventilation (week 2). Similarly, none of the secondary parameters was significantly changed either at week 2 or at the end of the study period (week 12). Five patients developed respiratory infections and two died because of pneumonia; this was judged as being unrelated to bosentan intake.

In conclusion, bosentan administration does not seem to induce clinically relevant gas exchange abnormalities in idiopathic pulmonary fibrosis patients.
Glutathione S-transferase genotypes modify lung function decline in the general population: SAPALDIA cohort study
Authors: Imboden Medea , Downs Sara H , Senn Oliver , Matyas Gabor , Brändli Otto , Russi Erich W , Schindler Christian , Ackermann-Liebrich Ursula , Berger Wolfgang , Probst-Hensch Nicole M ,   the SAPALDIA Team
Published: January 2007

Background

Understanding the environmental and genetic risk factors of accelerated lung function decline in the general population is a first step in a prevention strategy against the worldwide increasing respiratory pathology of chronic obstructive pulmonary disease (COPD). Deficiency in antioxidative and detoxifying Glutathione S-transferase (GST) gene has been associated with poorer lung function in children, smokers and patients with respiratory diseases. In the present study, we assessed whether low activity variants in GST genes are also associated with accelerated lung function decline in the general adult population.

Methods

We examined with multiple regression analysis the association of polymorphisms in GSTM1, GSTT1 and GSTP1 genes with annual decline in FEV1, FVC, and FEF25–75 during 11 years of follow-up in 4686 subjects of the prospective SAPALDIA cohort representative of the Swiss general population. Effect modification by smoking, gender, bronchial hyperresponisveness and age was studied.

Results

The associations of GST genotypes with FEV1, FVC, and FEF25–75 were comparable in direction, but most consistent for FEV1. GSTT1 homozygous gene deletion alone or in combination with GSTM1 homozygous gene deletion was associated with excess decline in FEV1 in men, but not women, irrespective of smoking status. The additional mean annual decline in FEV1 in men with GSTT1 and concurrent GSTM1 gene deletion was -8.3 ml/yr (95% confidence interval: -12.6 to -3.9) relative to men without these gene deletions. The GSTT1 effect on the FEV1 decline comparable to the observed difference in FEV1 decline between never and persistent smoking men. Effect modification by gender was statistically significant.

Conclusion

Our results suggest that genetic GSTT1 deficiency is a prevalent and strong determinant of accelerated lung function decline in the male general population.
Anterior anal sphincter repair can be of long term benefit: a 12-year case cohort from a single surgeon
Authors: Grey Benjamin R , Sheldon Rowena R , Telford Karen J , Kiff Edward S
Published: January 2007

Background

Early surgical results of anterior sphincter repair for faecal incontinence can be good, but in the longer term are often disappointing. This study aimed to determine the short and long term outcomes from anterior sphincter repair and identify factors predictive of long term success.

Methods

Patients who underwent anterior sphincter repair between 1989 and 2001 in one institution were identified. Postal questionnaires were sent to patients, which included validated scoring systems for symptom severity and quality of life assessments for faecal incontinence. Patient demographics and risk factors were recorded as were the results of anorectal physiology studies and endoanal ultrasound.

Results

Eighty-five patients underwent repair by one consultant. The length of follow up ranged from 1 to 12 years. Most patients (96%) had early symptom improvement postoperatively. Of the 47 patients assessed long term (≥ 5 years), 28 (60%) maintained this success. Significant improvements in quality of life were observed (P < 0.001). Neither patient, surgical nor anorectal physiology study parameters were predictive of outcome.

Conclusion

There were no predictive factors of outcome success and no changes in anal manometry identified, however anterior sphincter repair remains worthwhile. Changes in compliance of the anorectum may be responsible for symptom improvement.
Exploring the effects of telehealth on medical human resources supply: a qualitative case study in remote regions
Authors: Gagnon Marie-Pierre , Duplantie Julie , Fortin Jean-Paul , Landry Réjean
Published: January 2007

Background

The availability of medical human resource supply is a growing concern for rural and remote communities in many countries. In the last decade, various telehealth experiences in Canada have highlighted the potential impact of this technology on professional practice. The purpose of this study was to explore physicians' and managers' perceptions regarding the potential of telehealth to support recruitment and retention of physicians in remote and rural regions.

Methods

A case study in Eastern Quebec was performed to explore this complex phenomenon. The analytical framework was based on two literature reviews and a Delphi study. Data were collected from semi-structured interviews with 41 physicians and 22 managers. Transcripts were produced and interview content was coded independently by two judges and validated by an expert panel.

Results

Interviews have highlighted the potential impact of telehealth on several factors influencing the recruitment and retention of physicians in rural and remote regions. The potential effects of telehealth on physicians' choice of practice location could be seen at the professional, organizational, educational and individual levels. For instance, telehealth could improve work satisfaction by allowing a regional on-call duty system and a better follow-up of patients. However, there are also certain limits related to telehealth, such as the fear that it would eventually replace all continuing medical education activities and onsite specialists in remoteregions.

Conclusion

Telehealth is likely to have an impact on several factors related to medical workforce supply in remote and rural regions. However, the expected benefits will materialize if and only if this technology is properly integrated into organizations as a support to professional practice.
Zebularine reactivates silenced E-cadherin but unlike 5-Azacytidine does not induce switching from latent to lytic Epstein-Barr virus infection in Burkitt's lymphoma Akata cells
Authors: Rao Sieta P , Rechsteiner Markus P , Berger Christoph , Sigrist Jürg A , Nadal David , Bernasconi Michele
Published: January 2007

Epigenetic silencing of regulatory genes by aberrant methylation contributes to tumorigenesis. DNA methyltransferase inhibitors (DNMTI) represent promising new drugs for anti-cancer therapies. The DNMTI 5-Azacytidine is effective against myelodysplastic syndrome, but induces switching of latent to lytic Epstein-Barr virus (EBV) in vitro and results in EBV DNA demethylation with the potential of induction of lytic EBV in vivo. This is of considerable concern given that recurrent lytic EBV has been linked with an increased incidence of EBV-associated lymphomas. Based on the distinct properties of action we hypothesized that the newer DNMTI Zebularine might differ from 5-Azacytidine in its potential to induce switching from latent to lytic EBV. Here we show that both 5-Azacytidine and Zebularine are able to induce expression of E-cadherin, a cellular gene frequently silenced by hypermethylation in cancers, and thus demonstrate that both DNMTI are active in our experimental setting consisting of EBV-harboring Burkitt's lymphoma Akata cells. Quantification of mRNA expression of EBV genes revealed that 5-Azacytidine induces switching from latent to lytic EBV and, in addition, that the immediate-early lytic infection progresses to early and late lytic infection. Furthermore, 5-Azacytidine induced upregulation of the latent EBV genes LMP2A, LMP2B, and EBNA2 in a similar fashion as observed following switching of latent to lytic EBV upon cross-linking of the B-cell receptor. In striking contrast, Zebularine did not exhibit any effect neither on lytic nor on latent EBV gene expression. Thus, Zebularine might be safer than 5-Azacytidine for the treatment of cancers in EBV carriers and could also be applied against EBV-harboring tumors, since it does not induce switching from latent to lytic EBV which may result in secondary EBV-associated malignancies.
Importance of A-loop complementarity with tRNAHis anticodon for continued selection of tRNAHis as the HIV reverse transcription primer
Authors: Ni Na , Xu Wenqin , Morrow Casey D
Published: January 2007

Background

Human immunodeficiency virus (HIV-1) preferentially selects tRNALys,3 as the primer for reverse transcription. HIV-1 can be forced to select alternative tRNAs through mutation in the primer-binding site (PBS) and a region upstream of the PBS designated as the A-loop. Alteration of the PBS and A-loop to be complementary to the 3' terminal nucleotides and anticodon of tRNAHis results in HIV-1 that can stably utilize this tRNA for replication.

Results

In the current study, we have investigated the effect that mutations within the A-loop have on the stability of HIV-1 with a PBS complementary to tRNAHis. For these studies, we have altered the A-loop to be complementary to tRNAMet, tRNAGln, tRNAIle, tRNAThr and tRNASer. All substitutions of the A-loops with the PBS complementary to tRNAHis resulted in a reduction of infectious virus obtained following transfection of proviral genomes in the 293T cells. Virus replication in SupT1 cells was also impaired as a result of the alteration of the A-loop. Viruses with the A-loop complementary to tRNALys,3 and tRNASer reverted to utilize tRNALys,3 following in vitro replication. In contrast, viruses with the A-loop complementary to the other tRNAs remained stable and continued to use tRNAHis. RNA modeling of the stem-loop structure revealed that nucleotides were displayed on the loop region that could potentially interact with the anticodon of tRNAHis. To further explore the effects of the A-loop mutations on virus replication, the A-loops complementary to tRNASer or tRNAHis were cloned into the wild type genome with the PBS complementary to tRNALys,3. Transfection of proviral genomes which contained the wild type PBS and A-loops complementary to tRNASer or tRNAHis into 293 T cells did not impact on the production of viruses as measured by p24 antigen ELISA. However, viruses with the A-loop complementary to tRNAHis had greatly reduced infectivity and replicated poorly in SupT1 compared to the wild type or viruses with the A-loop complementary to tRNASer.

Conclusion

These studies demonstrate that complementarity of A-loop region with the anticodon of tRNAHis has a pronounced effect on the capacity of HIV-1 to utilize tRNAHis as the primer for reverse transcription. Complementarity between A-loop and anticodon of the tRNA then is important for the selection of the tRNA primer used for reverse transcription.
Mutations in the TΨC Loop of E. coli tRNALys,3 Have Varied Effects on In Trans Complementation of HIV-1 Replication
Authors: Yu Wanfeng , McCulley Anna , Morrow Casey D
Published: January 2007

Background

Human immunodeficiency virus (HIV-1) exclusively selects and utilizes tRNALys,3 as the primer for initiation of reverse transcription. Several elements within the TΨC stem loop of tRNALys,3 are postulated to be important for selection and use in reverse transcription. The post-transcriptional modification at nucleotide 58 could play a role during plus-strand synthesis to stop reverse transcriptase from re-copying the tRNA primer. Nucleotides 53 and 54 within the TΨC stem loop of the tRNA have been shown to be important to form the complex between tRNA and the HIV-1 viral genome during initiation of reverse transcription.

Results

To further delineate the features of the TΨC stem loop of tRNALys,3 in reverse transcription, we have developed a complementation system in which E. coli tRNALys,3 is provided in trans to an HIV-1 genome in which the PBS is complementary to this tRNA. Successful selection and use of E. coli tRNALys,3 results in the production of infectious virus. We have used this single round infectious system to ascertain the effects that different mutants in the TΨC stem loop of tRNALys,3 have on complementation. Mutants were designed within the TΨC loop (nucleotide 58) and within the stem and loop of the TΨC loop (nucleotides 53 and 54). Analysis of the expression of E. coli tRNALys,3 mutants revealed differences in the capacity for aminoacylation, which is an indication of intracellular stability of the tRNA. Alteration of nucleotide 58 from A to U (A58U), T54G and TG5453CC all resulted in tRNALys,3 that was aminoacylated when expressed in cells, while a T54C mutation resulted in a tRNALys,3 that was not aminoacylated. Both the A58U and T54G mutated tRNALys,3 complemented HIV-1 replication similar to wild type E. coli tRNALys,3. In contrast, the TG5453CC tRNALys,3 mutant did not complement replication.

Conclusion

The results demonstrate that post-transcriptional modification of nucleotide 58 in tRNALys,3 is not essential for HIV-1 reverse transcription. In contrast, nucleotides 53 and 54 of tRNALys,3 are important for aminoacylation and selection and use of the tRNALys,3 in reverse transcription.
Basal-like grade III invasive ductal carcinoma of the breast: patterns of metastasis and long-term survival
Authors: Fulford Laura G , Reis-Filho Jorge S , Ryder Ken , Jones Chris , Gillett Cheryl E , Hanby Andrew , Easton Douglas , Lakhani Sunil R
Published: January 2007

Introduction

Cytokeratin (CK) 14, one of several markers expressed in normal myoepithelial/basal cells, is also expressed in a proportion of breast carcinomas. Previous studies have suggested that expression of such 'basal' markers predicts different biological behaviour, with more frequent lung and brain metastases and poorer prognosis than other carcinomas.

Methods

We performed CK14 immunohistochemistry on 443 grade III invasive ductal carcinomas with extended clinical follow-up (mean 116 months), and we correlated CK14 immunopositivity (basal-like phenotype) with clinicopathological criteria.

Results

Eighty-eight of 443 (20%) tumours showed CK14 expression. CK14-positive tumours were more likely to be oestrogen receptor-negative (p < 0.0001) and axillary node-negative (p = 0.001) than were CK14-negative cases. CK14-positive cases developed less bone and liver metastases (hazard ratio [HR] 0.49, p = 0.01, and HR 0.53, p = 0.035, respectively) but more frequent brain metastases (HR 1.92, p = 0.051). In patients without metastatic disease, disease-free survival in CK14-positive cases was significantly better than in CK14-negative cases (HR 0.65, p = 0.005). In patients with metastatic disease, however, CK14 positivity was associated with a poorer prognosis (HR 1.84, p = 0.001). The overall survival in CK14-positive and -negative patients was similar at 5 years (60% and 59%, respectively), but the long-term survival was better in CK14-positive patients (HR 0.69, p = 0.02).

Conclusion

These results demonstrate that basal-like tumours differ in their biological behaviour from other tumours, with a distinct pattern of metastatic spread. Compared to other grade III tumours, basal-like tumours appear to have a relatively good long-term survival but survival after metastases is poor.
Distinct functions of α-Spectrin and β-Spectrin during axonal pathfinding
Authors: Hülsmeier Jörn , Pielage Jan , Rickert Christof , Technau Gerd M. , Klämbt Christian , Stork Tobias
Published: January 2007

Cell-shape changes during development require a precise coupling of the cytoskeleton with proteins situated in the plasma membrane. Important elements controlling the shape of cells are the Spectrin proteins that are expressed as a subcortical cytoskeletal meshwork linking specific membrane receptors with F-actin fibers. Here, we demonstrate that Drosophila karussellmutations affect β-spectrin and lead to distinct axonal patterning defects in the embryonic CNS. karussell mutants display a slit-sensitive axonal phenotype characterized by axonal looping in stage-13 embryos. Further analyses of individual, labeled neuroblast lineages revealed abnormally structured growth cones in these animals. Cell-type-specific rescue experiments demonstrate that β-Spectrin is required autonomously and non-autonomously in cortical neurons to allow normal axonal patterning. Within the cell, β-Spectrin is associated withα-Spectrin. We show that expression of the two genes is tightly regulated by post-translational mechanisms. Loss of β-Spectrin significantly reduces levels of neuronal α-Spectrin expression, whereas gain of β-Spectrin leads to an increase in α-Spectrin protein expression. Because the loss of α-spectrin does not result in an embryonic nervous system phenotype, β-Spectrin appears to act at least partially independent of α-Spectrin to control axonal patterning.
Fibroblast growth factor receptor 2 tyrosine kinase is required for prostatic morphogenesis and the acquisition of strict androgen dependency for adult tissue homeostasis
Authors: Lin Yongshun , Liu Guoqin , Zhang Yongyou , Hu Ya-Ping , Yu Kai , Lin Chunhong , McKeehan Kerstin , Xuan Jim W. , Ornitz David M. , Shen Michael M. , Greenberg Norman , McKeehan Wallace L. , Wang Fen
Published: January 2007

The fibroblast growth factor (FGF) family consists of 22 members and regulates a broad spectrum of biological activities by activating diverse isotypes of FGF receptor tyrosine kinases (FGFRs). Among the FGFs, FGF7 and FGF10 have been implicated in the regulation of prostate development and prostate tissue homeostasis by signaling through the FGFR2 isoform. Using conditional gene ablation with the Cre-LoxP system in mice, we demonstrate a tissue-specific requirement for FGFR2 in urogenital epithelial cells - the precursors of prostatic epithelial cells - for prostatic branching morphogenesis and prostatic growth. Most Fgfr2 conditional null(Fgfr2cn) embryos developed only two dorsal prostatic (dp)and two lateral prostatic (lp) lobes. This contrasts to wild-type prostate,which has two anterior prostatic (ap), two dp, two lp and two ventral prostatic (vp) lobes. Unlike wild-type prostates, which are composed of well developed epithelial ductal networks, the Fgfr2cnprostates, despite retaining a compartmented tissue structure, exhibited a primitive epithelial architecture. Moreover, although Fgfr2cn prostates continued to produce secretory proteins in an androgen-dependent manner, they responded poorly to androgen with respect to tissue homeostasis. The results demonstrate that FGFR2 is important for prostate organogenesis and for the prostate to develop into a strictly androgen-dependent organ with respect to tissue homeostasis but not to the secretory function, implying that androgens may regulate tissue homeostasis and tissue function differently. Therefore, Fgfr2cnprostates provide a useful animal model for scrutinizing molecular mechanisms by which androgens regulate prostate growth, homeostasis and function, and may yield clues as to how advanced-tumor prostate cells escape strict androgen regulations.
MRG-1, an autosome-associated protein, silences X-linked genes and protects germline immortality inCaenorhabditis elegans
Authors: Takasaki Teruaki , Liu Zheng , Habara Yasuaki , Nishiwaki Kiyoji , Nakayama Jun-ichi , Inoue Kunio , Sakamoto Hiroshi , Strome Susan
Published: January 2007

MRG15, a mammalian protein related to the mortality factor MORF4, is required for cell proliferation and embryo survival. Our genetic analysis has revealed that the Caenorhabditis elegans ortholog MRG-1 serves similar roles. Maternal MRG-1 promotes embryo survival and is required for proliferation and immortality of the primordial germ cells (PGCs). As expected of a chromodomain protein, MRG-1 associates with chromatin. Unexpectedly, it is concentrated on the autosomes and not detectable on the X chromosomes. This association is not dependent on the autosome-enriched protein MES-4. Focusing on possible roles of MRG-1 in regulating gene expression, we determined that MRG-1 is required to maintain repression in the maternal germ line of transgenes on extrachromosomal arrays, and of several X-linked genes previously shown to depend on MES-4 for repression. MRG-1 is not required for PGCs to acquire transcriptional competence or for the turn-on of expression of several PGC-expressed genes (pgl-1, glh-1, glh-4 and nos-1). By contrast to this result in PGCs, MRG-1 is required for ectopic expression of those germline genes in somatic cells lacking the NuRD complex component MEP-1. We discuss how an autosome-enriched protein might repress genes on the X chromosome, promote PGC proliferation and survival, and influence the germ versus soma distinction.
Johnsongrass (Sorghum Halepense) Control and Economics of Using Glyphosate-resistant Soybean in Fallowed Sugarcane Fields
Authors: Griffin James L. , Miller Donnie K. , Salassi Michael E.
Published: January 2007

Johnsongrass control in fallowed sugarcane fields was evaluated with glyphosate and the graminicides quizalofop, fluazifop, and clethodim applied in soybean compared with nonsoybean tillage and glyphosate programs. Glyphosate was applied to glyphosate-resistant soybean as a single early postemergence (EPOST) treatment around 30 d after planting (DAP) at rates of 840, 1,120, or 2,240 g ai/ha; as sequential treatments EPOST and late postemergence (LPOST) around 60 DAP at 560 followed by (fb) 560 or 1,120 fb 1,120 g/ha; or as a single LPOST treatment at 2,240 g/ha. Quizalofop at 77 g ai/ha, fluazifop at 420 g ai/ha, and clethodim at 280 g ai/ha were also evaluated as single EPOST treatments. In 1996 johnsongrass control 7 d after EPOST treatment (DAT) was at least 90% for glyphosate treatments but control was 73 to 77% for the graminicides. In 1997 johnsongrass control 7 DAT was at least 82% for all herbicide treatments. Excellent johnsongrass control approximately 50 DAT was achieved both years with all the glyphosate and graminicide treatments. In the nonsoybean fallow weed control programs where plots were tilled twice or three times fb one or two glyphosate applications, complete control of johnsongrass was obtained both years. In 1996 when glyphosate was applied EPOST or EPOST fb LPOST, soybean yields were equivalent and averaged 3.3 times that of the single LPOST glyphosate application. Soybean yields where the graminicides were used and where glyphosate was applied as a single LPOST treatment were no greater than the nontreated control. Economic analysis on the basis of soybean yield data and variable costs of herbicides, seed, field application, seedbed preparation, tillage, labor, fuel, repairs, and custom harvest expense in 1996 showed a positive net return only for glyphosate applied EPOST at 840 g/ha ($99.82/ha) or 1,120 g/ha ($46.94/ha) and for glyphosate applied at 560 g/ha EPOST fb LPOST ($10.41/ha). Although showing a negative net return, glyphosate applied EPOST at 2,240 g/ha ($−8.32/ha) or EPOST fb LPOST at 1,120 g/ha ($−50.97/ha), the loss was less than that for nonsoybean fallow tillage and glyphosate programs ($−155.70/ha and $−157.78/ha). In 1997, when soybean was not harvested because of environmental conditions, variable costs exceeded those of the nonsoybean programs, indicating that planting soybean strictly as a cover crop would not be economically advantageous. Sugarcane growth and yield the year following the fallow programs was not negatively affected by production of soybean regardless of herbicide program.
Glyphosate Can Reduce Glyphosate-resistant Canola Growth After Individual or Sequential Applications
Authors: Schilling Brian S. , Harker K. Neil , King Jane R.
Published: January 2007

Greenhouse experiments were conducted to determine whether multiple applications of glyphosate and time of glyphosate application with regard to the crop's growth stage had a significant effect on the growth and development of glyphosate-resistant canola. Glyphosate was applied as single applications at the two-, four-, or six-leaf stage of canola; as sequential double applications at the two- and four-, two- and six-, and four- and six-leaf stages of canola; and as a triple application at all three stages. Of the plant growth parameters measured, single applications of glyphosate resulted in significant reductions to stem weight and shoot weight compared with nontreated plants, and multiple applications of glyphosate caused significant reductions to leaf area, leaf weight, stem weight, and shoot weight. Single applications of glyphosate were less injurious to glyphosate-resistant canola compared with multiple applications, and canola growth parameter reductions were greatest after earlier glyphosate applications.