bluuebunny/crossref_metadata_2025 huggingface dataset:
World Information Flows and the Impact of New Technology
Authors: Ferguson Kerry
Published: March 2008

Communications is the fastest growing industry in the world due to a transformation of world information flows caused by the convergence of telecommunications, information technology, and mass media institutions. The emerging conglomerates are leading the world toward the information age. The new technology at their disposal is creating ever increasing world information flows, which are changing political, economic, and cultural landscapes and are redefining work, education, and development. The speed and uptake of new technology could not have been predicted, and its far-reaching political, economic, and social implications have only recently begun to emerge. This article argues that an international communications policy is necessary to ensure that the world does not divide into the information rich and the information poor.
Electronic Communities
Authors: Riedel Eric , Dresel Libby , Wagoner Marc J. , Sullivan John L. , Borgida Eugene
Published: March 2008

The recent implementation of a community electronic network is examined. The network is intended to help the rural community of Grand Rapids in northern Minnesota keep up with global technological progress. The present study is a baseline examination of social, political, and technological conditions in the community. Changes in social capital are hypothesized as a result of the wide-area network. Focus groups and survey research are used to assess inequalities in knowledge, access, and use of technologies as they relate to underlying inequalities in socioeconomic status and social capital. Results suggest that initial adoption of technological advances occurs among those with greater resources. Those with resources of social, but not necessarily economic, capital follow suit once an opportunity arises. Among the implications of the study's findings is that citizens lacking such resources need to be actively recruited into using the new technology as a means to bolster their existing resources.
The Internet and Political Mobilization
Authors: Bimber Bruce
Published: March 2008

This article examines the extent of Internet-based political mobilization during the 1996 election season. Using a sample of politically engaged Internet users from an online survey, along with data from random-digit-dial phone surveys, the article analyzes the extent of political use of the Internet and the nature of contacts with citizens made by eight categories of organization during the campaigns. It compares the extent of contacts made through electronic mail with contacts by phone, by mail, and in person. The article suggests that traditionally influential, national political organizations were apparently the most active in using the Internet for contacting voters and potential voters, but also that nontraditional, alternative mobilizers were comparatively more reliant on electronic mail and used it to reach a proportionately larger fraction of people not otherwise contacted.
The Leadership Principles Used by Jack Welch as he Re-energized, Revolutionized, and Reshaped General Electric
Authors: Strohmeier Brian R.
Published: March 2008

Starting in the early 1980s till now, Jack Welch, Chief Executive Officer (CEO) of the General Electric Corporation (GE), has led his company through one of the most revolutionary and far-reaching changes ever witnessed in modern business history. Under Welch's leadership, GE rose to be ranked No. 1 among the world's most valuable companies based on a combination of revenues, profits, market value, and assets. This article will discuss some of the leadership principles that Welch used to cause such a major revolution in the social, political, and economic climate at GE.
Leadership Effectiveness and Personality Characteristics of Group Members
Authors: Sogunro Olusegun Agboola
Published: March 2008

Perceptions of leadership appear to be changing. Research has shown a shift in emphasis in regard to the factors influencing leadership effectiveness in a group. Whereas early scholars focused on leaders personality characteristics as key to leadership effectiveness in group situations, today, there has been a turning toward a concern for group members' characteristics and a parallel concern for the ensuing influence on leadership behavior. The old belief that only the leader has the inherent ability to make things happen has been found wanting. Emphasis is fast shifting away from the idea that leadership effectiveness is unilaterally influenced by the leader's personality characteristics toward the notion that leadership effectiveness is bilaterally influenced by the dynamics of both the leader and the group members' personality characteristics. This paper presents some findings of research on leadership to support the critical influence of group members' characteristics on leadership effectiveness. Implications are noted for leaders, trainers, and researchers.
The Case for Using both Latent and Manifest Variables to Investigate Management-by-Exception
Authors: Densten lain L. , Gray Judy H.
Published: March 2008

The current study examines the leadership behavior of Management-by-Exception by using quantitative and qualitative methods. By distinguishing between manifest (observable) and latent (unobservable) variables, the study enables the concept of Management-by-Exception to be clarified. A sample 480 senior police officers was used. The results support the notion that Management-by-Exception should be considered as a single latent variable. Qualitative analysis identified three manifest variables that are observable indicators of Management-of-Exception. Implications for investigating leadership using both quantitative and qualitative research methods are discussed.
Running to Stand Still
Authors: DeFilippis James , Wyly Elvin
Published: March 2008

Research and policy on the geography of assisted housing is dominated by a powerful conventional wisdom: Project-based subsidies are presumptively bad because they anchor assisted households in poor, racially segregated neighborhoods, while vouchers are inherently good because they promote deconcentration and integration through tenant choice. Unfortunately, this consensus is based on geographical assumptions that have been subverted by the dramatic restructuring of cities with tight housing markets over the last generation. In this study, we use the case of New York City to analyze these spatial contradictions. Project-based subsidized housing is disappearing from yesterday's poor neighborhoods that have been remade by gentrification at the urban core, while recipients of Housing Choice Vouchers are concentrated in today's poor neighborhoods of color farther from the city center. If the policy goal is to break the link between housing assistance and the stereotypes of “projects” in the worst neighborhoods, then in the case of tight, expensive urban housing markets, voucher-driven deconcentration will be less successful than the preservation of the existing project-based housing stock.
Influencia de la época de cosecha sobre las características de la granadilla morada (Passiflora edulis Sims) y su jugo/Influence of harvest season on the characteristics of purple passion fruit (Passiflora edulis Sims) and its juice
Authors: Sáenz C. , Sepúlveda E. , Navarrete A. , Rustom A.
Published: March 2008

The effect of two different harvest seasons (winter and summer) on some characteristics of passion fruit and juice was studied. Three different harvests were made during the two seasons every 15-20 days. The soluble solids/acid ratio was used as a ripeness index. The weight, diameter, peel thickness and yield of juice and seeds were determined in the fruit. Soluble solids, pH, acidity, total and reduced sugars, starch, pectin and pectinesterase activity were determined in the juice. A sensory evaluation of the quality and intensity of aroma was made. Influence of the date of harvest on the technological characteristics of the fruit and juice were observed. Winter fruits showed higher weight, diameter and peel thickness and lower juice yield than those from the summer harvest. The juice from the summer harvest showed a higher content of soluble solids, less acidity, and a higher content in starch, pectin and sugars than that of the summer harvest. The sensory evaluation showed that the aroma of the juice from the summer harvest was better in intensity and quality than that of the winter fruit.
Sunlight Resistant Cotton/Kevlar® Blend Canvas Fabrics
Authors: Ruppenicker G.F. , Harper R.J. , Sawhney A.P.S. , Robert K.Q.
Published: March 2008

Cotton/Kelvar® 29 aramid 2 blend canvas fabrics were prepared from both Dref-3 friction-spun and conventional ring-spun yarns. The Dref-3 yarns were spun with cotton/Kevlar staple-blend cores and 100% cotton wrapping fibers, whereas the ring-spun yarns were an intimate blend. The fabrics were treated with a special finish containing titanium dioxide and a fluorocarbon water repellent Properties of the fabrics before and after accelerated weathering exposure in an Atlas Weatherometer were compared. The special finish improved the durability of both the Dref and ring spun fabrics to prolonged weathering. Strength retention, however, was best for the fabrics made from the Dref yarns.
Impregnated Fiber Glass Yarns for Reinforcing Industrial Coated Fabrics
Authors: Girgis Mikhail M.
Published: March 2008

A novel, proprietary, polymeric coating has been developed to impregnate glass fibers to form HercuFlex™ strands. These strands have been woven or knitted into fabrics. The physical properties of these fabrics have been determined and compared to conventional fabrics made of fiber glass yarns or organic fibers. The effects of tem perature, humidity, U.V. radiation, and chemical environment on the strength and flexibility of the strands as well as the fabrics were investigated and compared. Per formance requirements of reinforced coated fabrics for roofing and tension support structures have been found to be satisfied by woven or knitted fiber glass impreg nated yarns (HercuFlex™ strands) as the main reinforcing material Also, HercuFlex™ fabrics have great potential for high performance geotextiles and other industrial fabrics applications.
Erucoyl Glycolates as Lubricants for Cotton Yarns
Authors: Moreau J.P. , Bailey A.V.
Published: March 2008

Long-chain fatty acid derivatives of glycolic acid were evaluated as yarn lubricants for the preparation of cotton knitted fabrics. All experimental compounds imparted excellent lubricity, as measured by coefficient of friction, to both bleached and dyed cotton yarns. Yarns treated with polymeric sizing agents then topped with these compounds also exhibited improved lubricity. These treatments, therefore, have potential for greater efficiency in weaving as well as knitting fabrics. Frictional prop erties of these glycolic acid derivatives were among the best compared to commer cially available yarn lubricants.
Corrosion resistance of aluminium alloy pretreated based on bis-sulphur silane with rare earth salt
Authors: Wang Y.-F. , Wang R.-M. , Guo Z.-C.
Published: March 2008

Pretreatment for the Al alloy based on bis-[triethoxysilylpropyl]tetrasulphide (BTSPS) with Ce(NO3)3 is put forward in order to improve corrosion resistance of AA2024-T3 alloy in the present paper. The coating is formed by one step dip coating. The cross-linked pretreated coating on Al alloy is characterised with reflection absorption infrared spectroscopy. The chemical composition and the in depth distribution of different elements present in the coating are analysed by Auger electron spectroscopy. Corrosion resistance and hydrophobicity of pretreated coating on the Al alloy is respectively assessed by salt spray test, electrochemical tests and thermogravimetric analysis. The role of Ce3+ ion and sulphur present in one of the BTSPS solutions in the formation of the surface film is discussed. The results show that the one step pretreatment coating of BTSPS with Ce(NO3)3 provides excellent corrosion protection with the Al alloy compared with that of BTSPS without Ce(NO3)3.
Electrosynthesis of manganese oxide films
Authors: Wei J. , Zhitomirsky I.
Published: March 2008

Nanostructured manganese oxide films for electrochemical supercapacitors were obtained by cathodic electrosynthesis from aqueous NaMnO4 solutions. The proposed deposition mechanism is based on cathodic reduction of MnO4− species. The amount of the deposited material has been controlled by the variation of deposition time at a constant current density. Obtained films were studied by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction analysis, thermogravimetric and differential thermal analysis. It was found that the composition and microstructure of the films depend on the concentration of NaMnO4 in the solutions used for deposition. The films prepared from the 0˙02M NaMnO4 solutions were crack free and porous with typical pore size of about 100–200 nm. Cyclic voltammetry and chronopotentiometry data for the films tested in the 0˙1M Na2SO4 solutions showed capacitive behaviour in the voltage window of 0–1˙0 V versus standard calomel reference electrode. The highest specific capacitance of ∼220 F g−1 was obtained for 90 μg cm−2 films at a scan rate of 2 mV s−1 using Ni substrates. The capacitance decreased with increasing scan rate. The charge storage mechanism is discussed.
Deposition of Yarrowia lipolytica on plasma prepared teflonlike thin films
Authors: Lehocký M. , Amaral P. F. F. , Sťahel P. , Coelho M. A. Z. , Barros-Timmons A. M. , Coutinho J. A. P.
Published: March 2008

The adhesion of Yarrowia lipolytic a to teflonlike thin films deposited by plasma on polycarbonate substrates was investigated through a series of tests in order to develop a substrate for strong and selective adhesion of Yarrowia lipolytica cells. Teflonlike thin films were prepared using atmospheric pressure surface barrier discharge with mixtures of octafluorocyclobutane (C4F8) and nitrogen as plasma gas. A variety of plasma gas feedrates and different deposition times were studied. The films were characterised by Fourier transform infrared and contact angle measurements using the sessile drop technique. Total surface energy and its components were calculated using the acid base theory. Attachment of the yeast cells was assessed by optical and scanning electron microscopy. The optimal deposition conditions for cell adhesion were determined using standard adhesion tests.
Improving wear resistance of aluminium alloys by developing FTC and TiC based composite coatings using plasma powder arc welding process
Authors: Dilthey U. , Kondapalli S. , Balashov B. , Riedel F.
Published: March 2008

The aluminium alloys have enormous potentional of weight saving that are drastically gaining importance in the production of transport systems, for example, automobiles, aircraft and aerospace vehicles as well as in production of machines. Owing to the lack of sufficient abrasive wear resistance of aluminium components their application has, so far, been restricted. However, the application range of aluminium components will be extensible through the improvement of the abrasive wear resistance. The main objective of this work is the development of high wear resistant composite coatings on aluminium components by plasma transferred arc (PPA) welding. In this paper the development of the fused tungsten carbide and TiC based composite coatings with a thickness range of a few millimetres is presented. Aluminium alloys are used as matrix material and fused tungsten carbide and TiC are used as hard particles. The weldability of the powder systems with varying welding parameters is examined. The developed coating systems are tested with regard to their specific properties and their wear resistance. Finally, their application potential is presented.
Analysis of regulatory T-cell changes in patients with idiopathic thrombocytopenic purpura receiving B cell–depleting therapy with rituximab
Authors: Stasi Roberto , Cooper Nichola , Del Poeta Giovanni , Stipa Elisa , Laura Evangelista Maria , Abruzzese Elisabetta , Amadori Sergio
Published: March 2008

The effects of B-cell depletion with rituximab on regulatory T cells (Tregs) have not been determined. We investigated Tregs in patients receiving rituximab for chronic idiopathic thrombocytopenic purpura (ITP). The peripheral blood Tregs, identified as CD4+FOXP3+ T cells, were measured by flow cytometry prior to and after the immunotherapy. In addition, Tregs were analyzed for their usage of the T-cell receptor (TCR) β-variable (VB) region gene as well as their regulatory function as assessed by cell proliferation assays. Pretreatment data revealed a reduced number and a defective suppressive capacity of Tregs in ITP patients compared with control individuals. In addition, Tregs showed a polyclonal spectratype. Patients, particularly responders, showed restored numbers of Tregs as well as a restored regulatory function upon treatment with rituximab. These results indicate that patients with active ITP have a defective T regulatory cell compartment that can be modulated by a B cell–targeted therapy.
Prostacyclin therapies for the treatment of pulmonary arterial hypertension
Authors: Gomberg-Maitland M. , Olschewski H.
Published: March 2008

Prostacyclin and its analogues (prostanoids) are potent vasodilators and possess antithrombotic, antiproliferative and anti-inflammatory properties. Pulmonary hypertension (PH) is associated with vasoconstriction, thrombosis and proliferation, and the lack of endogenous prostacyclin may considerably contribute to this condition. This supports a strong rationale for prostanoid use as therapy for this disease. The first experiences of prostanoid therapy in PH patients were published in 1980.

Epoprostenol, a synthetic analogue of prostacyclin, and the chemically stable analogues iloprost, beraprost and treprostinil were tested in randomised controlled trials. The biological actions are mainly mediated by activation of specific receptors of the target cells; however, new data suggest effects on additional intracellular pathways. In the USA and some European countries, intravenous infusion of epoprostenol and treprostinil, as well as subcutaneous infusion of treprostinil and inhalation of iloprost, have been approved for therapy of pulmonary arterial hypertension. Iloprost infusion and beraprost tablets have been approved in few other countries. Ongoing clinical studies investigate oral treprostinil, inhaled treprostinil and the combination of inhaled iloprost and sildenafil in pulmonary arterial hypertension. Combination of other targeted therapies with prostanoids appears to be effective and safe.

After 25 yrs of continued knowledge, prostanoids remain a mainstay in the treatment of pulmonary arterial hypertension.
The biology of oxygen: Fig. 1—
Authors: Wagner P. D.
Published: March 2008

The biology of O2is extremely complex and defies a comprehensive yet brief summary that showcases its roles across the entire animal and plant kingdom. This necessarily short introduction to the 2006 Taormina Lung Science Conference (Taormina, Italy) on hypoxia will examine key features of the biology of O2only within mammalian cells, even that being a daunting task.
Simultaneous fitting of real-time PCR data with efficiency of amplification modeled as Gaussian function of target fluorescence
Authors: Batsch Anke , Noetel Andrea , Fork Christian , Urban Anita , Lazic Daliborka , Lucas Tina , Pietsch Julia , Lazar Andreas , Schömig Edgar , Gründemann Dirk
Published: March 2008

Background

In real-time PCR, it is necessary to consider the efficiency of amplification (EA) of amplicons in order to determine initial target levels properly. EAs can be deduced from standard curves, but these involve extra effort and cost and may yield invalid EAs. Alternatively, EA can be extracted from individual fluorescence curves. Unfortunately, this is not reliable enough.

Results

Here we introduce simultaneous non-linear fitting to determine – without standard curves – an optimal common EA for all samples of a group. In order to adjust EA as a function of target fluorescence, and still to describe fluorescence as a function of cycle number, we use an iterative algorithm that increases fluorescence cycle by cycle and thus simulates the PCR process. A Gauss peak function is used to model the decrease of EA with increasing amplicon accumulation. Our approach was validated experimentally with hydrolysis probe or SYBR green detection with dilution series of 5 different targets. It performed distinctly better in terms of accuracy than standard curve, DART-PCR, and LinRegPCR approaches. Based on reliable EAs, it was possible to detect that for some amplicons, extraordinary fluorescence (EA > 2.00) was generated with locked nucleic acid hydrolysis probes, but not with SYBR green.

Conclusion

In comparison to previously reported approaches that are based on the separate analysis of each curve and on modelling EA as a function of cycle number, our approach yields more accurate and precise estimates of relative initial target levels.
Altered patterns of gene duplication and differential gene gain and loss in fungal pathogens
Authors: Powell Amy J , Conant Gavin C , Brown Douglas E , Carbone Ignazio , Dean Ralph A
Published: March 2008

Background

Duplication, followed by fixation or random loss of novel genes, contributes to genome evolution. Particular outcomes of duplication events are possibly associated with pathogenic life histories in fungi. To date, differential gene gain and loss have not been studied at genomic scales in fungal pathogens, despite this phenomenon's known importance in virulence in bacteria and viruses.

Results

To determine if patterns of gene duplication differed between pathogens and non-pathogens, we identified gene families across nine euascomycete and two basidiomycete species. Gene family size distributions were fit to power laws to compare gene duplication trends in pathogens versus non-pathogens. Fungal phytopathogens showed globally altered patterns of gene duplication, as indicated by differences in gene family size distribution. We also identified sixteen examples of gene family expansion and five instances of gene family contraction in pathogenic lineages. Expanded gene families included those predicted to be important in melanin biosynthesis, host cell wall degradation and transport functions. Contracted families included those encoding genes involved in toxin production, genes with oxidoreductase activity, as well as subunits of the vacuolar ATPase complex. Surveys of the functional distribution of gene duplicates indicated that pathogens show enrichment for gene duplicates associated with receptor and hydrolase activities, while euascomycete pathogens appeared to have not only these differences, but also significantly more duplicates associated with regulatory and carbohydrate binding functions.

Conclusion

Differences in the overall levels of gene duplication in phytopathogenic species versus non-pathogenic relatives implicate gene inventory flux as an important virulence-associated process in fungi. We hypothesize that the observed patterns of gene duplicate enrichment, gene family expansion and contraction reflect adaptation within pathogenic life histories. These adaptations were likely shaped by ancient, as well as contemporary, intimate associations with monocot hosts.
IL-4/IL-13 independent goblet cell hyperplasia in experimental helminth infections
Authors: Marillier Reece G , Michels Chesney , Smith Elizabeth M , Fick Lizette CE , Leeto Mosiuoa , Dewals Benjamin , Horsnell William GC , Brombacher Frank
Published: March 2008

Background

Intestinal mucus production by hyperplasic goblet cells is a striking pathological feature of many parasitic helminth infections and is related to intestinal protection and worm expulsion. Induction of goblet cell hyperplasia is associated with TH2 immune responses, which in helminth infections are controlled primarily by IL-13, and also IL-4. In the study presented here we examine the goblet cell hyperplasic response to three experimental parasitic helminth infections; namelyNippostrongylus brasiliensis,Syphacia obvelataandSchistosoma mansoni.

Results

As expectedN. brasiliensisinfection induced a strong goblet cell hyperplasia dependent on IL-4/IL-13/IL-4Rα expression. In contrast, and despite previously published transiently elevated IL-4/IL-13 levels,S. obvelatainfections did not increase goblet cell hyperplasia in the colon. Furthermore, induction of goblet cell hyperplasia in response toS. mansonieggs traversing the intestine was equivalent between BALB/c, IL-4/IL-13-/-and IL-4Rα-/-mice.

Conclusion

Together these data demonstrate that intestinal goblet cell hyperplasia can be independent of TH2 immune responses associated with parasitic helminth infections.
Pesticide exposure and risk of Parkinson's disease: A family-based case-control study
Authors: Hancock Dana B , Martin Eden R , Mayhew Gregory M , Stajich Jeffrey M , Jewett Rita , Stacy Mark A , Scott Burton L , Vance Jeffery M , Scott William K
Published: March 2008

Background

Pesticides and correlated lifestyle factors (e.g., exposure to well-water and farming) are repeatedly reported risk factors for Parkinson's disease (PD), but few family-based studies have examined these relationships.

Methods

Using 319 cases and 296 relative and other controls, associations of direct pesticide application, well-water consumption, and farming residences/occupations with PD were examined using generalized estimating equations while controlling for age-at-examination, sex, cigarette smoking, and caffeine consumption.

Results

Overall, individuals with PD were significantly more likely to report direct pesticide application than their unaffected relatives (odds ratio = 1.61; 95% confidence interval, 1.13–2.29). Frequency, duration, and cumulative exposure were also significantly associated with PD in a dose-response pattern (p ≤ 0.013). Associations of direct pesticide application did not vary by sex but were modified by family history of PD, as significant associations were restricted to individuals with no family history. When classifying pesticides by functional type, both insecticides and herbicides were found to significantly increase risk of PD. Two specific insecticide classes, organochlorines and organophosphorus compounds, were significantly associated with PD. Consuming well-water and living/working on a farm were not associated with PD.

Conclusion

These data corroborate positive associations of broadly defined pesticide exposure with PD in families, particularly for sporadic PD. These data also implicate a few specific classes of pesticides in PD and thus emphasize the need to consider a more narrow definition of pesticides in future studies.
Tumor-derived matrix metalloproteinase-13 (MMP-13) correlates with poor prognosis of invasive breast cancer
Authors: Zhang Bin , Cao Xuchen , Liu Yanxue , Cao Wenfeng , Zhang Fei , Zhang Shiwu , Li Hongtao , Ning Liansheng , Fu Li , Niu Yun , Niu Ruifang , Sun Baocun , Hao Xishan
Published: March 2008

Background

Experimental evidence suggests that matrix metalloproteinase-13 (MMP-13) protein may promote breast tumor progression, however, its role is yet to be fully established. Furthermore, it is not clear whether MMP-13 can be used as an independent breast cancer biomarker. This study was conducted to assess the expression profile of MMP-13 protein in invasive breast carcinomas to determine its diagnostic and prognostic significance, as well as its correlation with other biomarkers including estrogen receptor (ER), progesterone receptor (PR), Her-2/neu, MMP-2, MMP-9, tissue inhibitor of MMP-1 and -2 (TIMP-1 and TIMP-2).

Methods

Immunohistochemistry (IHC) was performed on paraffin-embedded tissue microarray specimens from 263 breast carcinomas. The intensity and the extent of IHC were scored by pathologists. The correlation of the gene expression profiles with the patients' clinicopathological features and clinical outcomes were analyzed for statistical significance.

Results

MMP-13 protein was detected in the cytoplasm of malignant cells and peritumoral stromal cells. MMP-13 expression by tumor cells (p < 0.001) and stromal fibroblasts (p < 0.001) both correlated with carcinoma infiltration of lymph nodes. MMP-13 also correlated with the expression of Her-2/neu (p = 0.015) and TIMP-1 (p < 0.010), respectively in tumor cells. Tumor-derived, but not stromal fibroblast-derived, MMP-13 correlated with aggressive tumor phenotypes. Moreover, high levels of MMP-13 expression were associated with decreased overall survival. In parallel, the prognostic value of MMP-13 expressed by peritumoral fibroblasts seems less significant. Our data suggest that lymph node status, tumor size, Her-2/neu expression, TIMP-1 and MMP-13 expression in cancer cells are independent prognostic factors.

Conclusion

Tumor-derived, but not stromal fibroblast-derived, MMP-13 correlated with aggressive tumor phenotypes, and inversely correlated with overall survival of breast cancer patients. MMP-13 may serve as an independent prognostic factor for invasive breast cancer patients. MMP-13 may be particularly useful as a prognostic marker when evaluated along with Her-2/neu and lymph node status.
6thInternational Symposium on Retroviral Nucleocapsid
Authors: Berkhout Ben , Gorelick Robert , Summers Michael F , Mély Yves , Darlix Jean-Luc
Published: March 2008

Retroviruses and LTR-retrotransposons are widespread in all living organisms and, in some instances such as for HIV, can be a serious threat to the human health. The retroviral nucleocapsid is the inner structure of the virus where several hundred nucleocapsid protein (NC) molecules coat the dimeric, genomic RNA. During the past twenty years, NC was found to play multiple roles in the viral life cycle (Fig. 1), notably during the copying of the genomic RNA into the proviral DNA by viral reverse transcriptase and integrase, and is therefore considered to be a prime target for anti-HIV therapy. The 6th NC symposium was held in the beautiful city of Amsterdam, the Netherlands, on the 20th and 21st of September 2007. All aspects of NC biology, from structure to function and to anti-HIV vaccination, were covered during this meeting.
The effect of noise generated by previous shots on seismic reflection data
Authors: Landrø Martin
Published: March 2008

In marine seismic acquisition, the typical time interval between two adjacent shots is about [Formula: see text]. This interval is considered sufficient to avoid the signal from one shot interfering with the signal from the next shot. However, when we are looking for very weak signals or weak changes in a given signal (time-lapse seismic), the influence of the shot-generated noise can be of importance. In the present work, shot records with a recording time of [Formula: see text] are used to analyze the influence of the shot-generated noise from the previous shot. Simple decay models are used to match the observed rms decay curves. These calibrated models are used to estimate variations in signal-to-noise ratio versus shot time interval and source strength. For instance, if the source strength is doubled and the time interval between two shots is increased from [Formula: see text], an improvement in the signal-to-shot-generated noise from the previous shot of [Formula: see text] is expected. Especially for time-lapse seismic using permanently installed receivers, this way of increasing the S/N might be useful.
Integrated multidisciplinary diagnostic approach for dementia
care: Randomised controlled trial
Authors: Wolfs Claire A. G. , Kessels Alfons , Dirksen Carmen D. , Severens Johan L. , Verhey F. R. J.
Published: March 2008

Background

An integrated multidisciplinary approach to dementia is often recommended
but has rarely been evaluated.

Aims

To evaluate the clinical effects of an integrated multidisciplinary
diagnostic facility for psychogeriatric patients.

Method

Patients suspected of having complex psychogeriatric problems were
randomly allocated to the intervention (n=137) or to
treatment as usual (n=93). They were assessed at
baseline, and at 6 months and 12 months follow-up by means of personal
interviews with the patient's proxy. The primary outcome was
health-related quality of life, assessed using the visual analogue scale
(VAS) of the EuroQd measure, EQ-5D.

Results

Health-related quality of life had improved at 6 months in the
intervention group, whereas that of the control group had decreased.
Furthermore, more patients in the intervention group experienced a
clinically relevant improvement of 10 points or more on the VAS at both
follow-up measurements.

Conclusions

An integrated multidisciplinary approach improves dementia care.
Predictive value of folate, vitamin B12 and
homocysteine levels in late-life depression
Authors: Kim Jae-Min , Stewart Robert , Kim Sung-Wan , Yang Su-Jin , Shin Il-Seon , Yoon Jin-Sang
Published: March 2008

Background

The role of folate, vitamin B12 and homocysteine levels in
depression is not clear.

Aims

To investigate cross-sectional and prospective associations between
folate, B12 and homocysteine levels and late-life
depression.

Method

A total of 732 Korean people aged 65 years or over were evaluated at
baseline. Of the 631 persons who were not depressed, 521 (83%) were
followed over a period of 2–3 years and incident depression was
ascertained with the Geriatric Mental State schedule. Serum folate, serum
vitamin B12 and plasma homocysteine levels were assayed at
both baseline and follow-up.

Results

Lower levels of folate and vitamin B12 and higher homocysteine
levels at baseline were associated with a higher risk of incident
depression at follow-up. Incident depression was associated with a
decline in vitamin B12 and an increase in homocysteine levels
over the follow-up period.

Conclusions

Lower folate, lower vitamin B12 and raised homocysteine levels
may be risk factors for late-life depression.
Liaison psychiatry services in Wales
Authors: Sakhuja Divya , Bisson Jonathan I.
Published: March 2008

Aims and Method

To determine the nature of current liaison psychiatry services in Wales, a structured telephone interview was conducted with representatives of all 11 National Health Service trusts.

Results

Three trusts (27%) had no dedicated liaison psychiatry service and only one of the eight (13%) with a service had a full-time consultant liaison psychiatrist. Only two services (25%) had a full-time junior doctor and three (37%) were not multidisciplinary, comprising nursing staff alone. No team had a clinical psychologist and only two (25%) provided a psychological treatment service.

Clinical Implications

Liaison psychiatry services across Wales are fragmented, under-resourced and unlikely to meet patients' needs. They fall well short of the recommendations of the Royal Colleges of Physicians and Psychiatrists.
Promiscuous Anaerobes
Authors: Grochowski Laura L. , White Robert H.
Published: March 2008

The development of an oxygenated atmosphere on earth resulted in the polarization of life into two major groups, those that could live in the presence of oxygen and those that could not—the aerobes and the anaerobes. The evolution of aerobes from the earliest anaerobic prokaryotes resulted in a variety of metabolic adaptations. Many of these adaptations center on the need to sustain oxygen‐sensitive reactions and cofactors to function in the new oxygen‐containing atmosphere. Still other metabolic pathways that were not sensitive to oxygen also diverged. This is likely due to the physical separation of the organisms, based on their ability to live in the presence of oxygen, which allowed for the independent evolution of the pathways. Through the study of metabolic pathways in anaerobes and comparison to the more established pathways from aerobes, insight into metabolic evolution can be gained. This, in turn, can allow for extra‐ polation to those metabolic pathways occurring in the Last Universal Common Ancestor (LUCA). Some of the unique and uncanonical metabolic pathways that have been identified in the archaea with emphasis on the biochemistry of an obligate anaerobic methanogen, Methanocaldococcus jannaschii are reviewed.
Microbiology to Help Solve Our Energy Needs
Authors: Grigoryan Alexander , Voordouw Gerrit
Published: March 2008

Our society depends greatly on fossil fuels, and the environmental consequences of this are well known and include significant increases of the CO2 concentration in the earth's atmosphere. Although microbiology has traditionally played only a minor role in fossil‐fuel extraction, two novel key discoveries indicate that this may change. First, the realization that oil components can be converted to methane and CO2 by methanogenic consortia in the absence of electron acceptors (oxygen, nitrate, sulfate) explains how much of the world's oil has been biodegraded in situ. In addition to inorganic nutrients, only water is needed for these methanogenic conversions. Hence, continued methanogenic biodegradation may have shaped the heavy‐oil reservoirs that are so prevalent today. The potential to exploit these reactions, for example, by in situ gasification, is currently being actively investigated. Second, injection of nitrate in oil and gas fields can lower sulfide concentrations. High sulfide concentrations, caused by the action of sulfate‐reducing bacteria (SRB), are associated with increased risk of corrosion, reservoir plugging (through precipitated sulfides), and human safety. Nitrate injection into an oil field stimulates subsurface heterotrophic nitrate‐reducing bacteria (hNRB) and nitrate‐reducing, sulfide‐oxidizing bacteria (NR‐SOB). Nitrite, formed by these NRB by partial reduction of nitrate, is a strong and specific SRB inhibitor. Nitrate injection has, therefore, promise in positively controlling the oil‐field sulfur cycle. There is now more interest in and potential to apply petroleum microbiology than there has been in the past, allowing microbiologists to contribute to a sustainable energy future.
Transformation of Inorganic and Organic Arsenic byAlkaliphilus oremlandiisp. nov. Strain OhILAs
Authors: Fisher Edward , Dawson Asia M. , Polshyna Ganna , Lisak Joy , Crable Bryan , Perera Eranda , Ranganathan Mrunalni , Thangavelu Mirunalni , Basu Partha , Stolz John F.
Published: March 2008

Alkaliphilus oremlandii sp. nov. strain OhILAs is a mesophilic, spore‐forming, motile, low mole%GC gram positive. It was enriched from Ohio River sediments on a basal medium with 20 mM lactate and 5 mM arsenate and isolated through passage on medium with increased arsenic concentration (10 and 20 mM), tindalization, and serial dilution. The pH optimal for growth was 8.4 and 16S rRNA gene sequence analysis indicated it is most closely related to species in the genus Alkaliphilus (A. crotonoxidans 95%, A. auruminator 95%, A. metalliredigens, 94%). A strict anaerobe, it can ferment lactate via the acrylate pathway as well as fructose and glycerol. A. oremlandii also has respiratory capability, as it is able to use arsenate and thiosulfate as terminal electron acceptors with acetate, pyruvate, formate, lactate, fumarate, glycerol, or fructose as the electron donor. A respiratory arsenate reductase, which is constitutively expressed, has been identified through biochemical and Western blot analyses and confirmed by cloning and sequencing of the gene encoding the structural subunit arrA. The entire arr operon as well as the ars operon have also been identified in the fully annotated genome. A. oremlandii also transforms the organoarsenical 3‐nitro‐4‐hydroxy benzene arsonic acid (roxarsone). Growth experiments and genomic analysis suggest that it couples the reduction of the nitro group of the organoarsenical to the oxidation of either lactate or fructose in a dissimilatory manner, generating ATP via a sodium dependent ATP synthase.
Fermentative Butanol Production
Authors: Dürre Peter
Published: March 2008

Clostridium acetobutylicum is an anaerobic, spore‐forming bacterium with the ability to ferment starch and sugars into solvents. In the past, it has been used for industrial production of acetone and butanol, until cheap crude oil rendered petrochemical synthesis more economically feasible. Both economic (price of crude oil) and environmental aspects (carbon dioxide emissions) have caused the pendulum to swing back again. Molecular biology has allowed a detailed understanding of genes and enzymes, required for solventogenesis. Thus, construction of strains with improved fermentation ability is now possible. Advances in continuous culture technology and improved downstream processing also add to economic advantages of a new biotechnological process. Two major companies have already committed themselves to biobutanol production as a biofuel additive. Thus, butanol fermentation is on the rise again.
Retrospective Study of Childhood Ganglioneuroma
Authors: De Bernardi Bruno , Gambini Claudio , Haupt Riccardo , Granata Claudio , Rizzo Antonino , Conte Massimo , Tonini Gian Paolo , Bianchi Maurizio , Giuliano Maria , Luksch Roberto , Prete Arcangelo , Viscardi Elisabetta , Garaventa Alberto , Sementa Angela Rita , Bruzzi Paolo , Angelini Paola
Published: March 2008

Purpose

To review a historical cohort of childhood ganglioneuroma (GN), the benign representative of the peripheral neuroblastic tumor (PNT) family.

Patients and Methods

Of 2,286 PNTs enrolled between 1979 and 2005, 146 (6.4%) were registered as GN. Histological revision was carried out on 76 tumors. Diagnosis was confirmed in 45, while 27 were reclassified as ganglioneuroblastoma intermixed (GNBI) and four were reclassified as other PNT subtypes.

Results

GNs differed from other PNTs for sex, age, tumor site, stage, tumor markers, and scintigraphic results. Characteristics of 76 reviewed and 70 nonreviewed patients were comparable. Reviewed GN and GNBI patients were comparable except for homovanillic acid excretion, metaiodobenzylguanidine scintigraphy, and DNA content. Seven patients were only biopsied and 139 underwent surgery. Twenty-two patients suffered surgery-related complications, of which two were fatal and seven were severe. Radical tumor resection and surgery-related complication rates were comparable for GN, GNBI, and nonreviewed instances. Six patients developed tumor progression but survived. Two patients developed a late malignancy but survived. None of the 146 patients received chemotherapy. Of 146 patients, two died of surgery-related complications and 144 survived.

Conclusion

Diagnosis was changed to GNBI for approximately one third of 76 reviewed tumors. Patients with confirmed GN, reclassified as GNBI, and nonreviewed histology presented with comparable clinical, biochemical, and biologic features. Surgical results, complication rate, number of progressions, and outcome were similar for the three groups. Surgery was associated with significant risk of complications. Survival was not influenced by extent of tumor resection. Aggressive surgical approach should not be recommended for childhood GN and GNBI.
Phase III Trial of Pemetrexed Plus Best Supportive Care Compared With Best Supportive Care in Previously Treated Patients With Advanced Malignant Pleural Mesothelioma
Authors: Jassem Jacek , Ramlau Rodryg , Santoro Armando , Schuette Wolfgang , Chemaissani Assad , Hong Shengyan , Blatter Johannes , Adachi Susumu , Hanauske Axel , Manegold Christian
Published: March 2008

Purpose

This multicenter, phase III study compared overall survival (OS) of second-line pemetrexed plus best supportive care (BSC) versus BSC alone in patients with advanced malignant pleural mesothelioma (MPM). Secondary end points included response rate, progression-free survival (PFS), time to tumor progression (TTP), time to treatment failure (TTF), and toxicity.

Patients and Methods

Patients with relapsed MPM after first-line chemotherapy were randomly assigned to receive pemetrexed 500 mg/m2 plus BSC (P+BSC) every 21 days or BSC alone.

Results

The study enrolled 243 patients (123 on P+BSC arm and 120 on BSC arm). Median OS time was not significantly different between the arms (8.4 months for P+BSC and 9.7 months for BSC; P = .74). Cox regression modeling suggested a trending survival benefit for patients who responded to first-line therapy. Time-to-event measures significantly favored P+BSC (median PFS, TTP, and TTF). Partial response was achieved in 18.7% and 1.7% of patients in P+BSC and BSC arms, respectively (P < .0001), and a disease control rate (partial response plus stable disease) was achieved in 59.3% and 19.2% of patients in P+BSC and BSC arms, respectively (P < .0001). Use of postdiscontinuation chemotherapy was significantly greater among BSC patients compared with P+BSC patients (51.7% v 28.5%, respectively; P = .0002), with more BSC patients receiving pemetrexed (18.3% v 3.3%, respectively; P = .0001). Postdiscontinuation therapy was initiated earlier for BSC than P+BSC patients (median time to initiation, 4.3 v 15.7 months, respectively; log-rank P < .0001). Chemotherapy was well tolerated, with expected modest (4% to 7%) grade 3 and 4 hematologic toxicities.

Conclusion

Second-line pemetrexed elicited significant tumor response and delayed disease progression compared with BSC alone in patients with advanced MPM. Improvement in OS was not seen in this study, possibly because of the significant imbalance in postdiscontinuation chemotherapy between the arms.
Structure and Clinical Relevance of the Epidermal Growth Factor Receptor in Human Cancer
Authors: Kumar Amit , Petri Edward T. , Halmos Balazs , Boggon Titus J.
Published: March 2008

Purpose

To review the recent advances in the atomic-level understanding of the epidermal growth factor receptor (EGFR) tyrosine kinase (TK). We aim to highlight the current and future importance of these studies for the understanding and treatment of malignancies where EGFR-TK is improperly activated.

Methods

The analysis was conducted on published crystal structures deposited in the Protein Data Bank ( www.pdb.org ) using the program O.

Results

In this review we emphasize how recent EGFR kinase domain crystal structures can explain the mechanisms of activation for L858R and other EGFR-TK mutations, and compare these distinct activating mechanisms with those recently described for the wild-type EGFR. We suggest an atomic-level mechanism for the poor efficacy of lapatinib against tumors with activating EGFR kinase domain point mutations compared with the efficacy of gefitinib and erlotinib, and demonstrate how structural insights help our understanding of acquired resistance to these agents. We also highlight how these new molecular-level structural data are expected to affect the development of EGFR-TK targeted small molecule kinase inhibitors.

Conclusion

There are now more crystal structures published for the EGFR-TK domain than for any other TK. This wealth of crystallographic information is beginning to describe the mechanisms by which proper regulation of EGFR-TK is lost in disease. These crystal structures are beginning to show how small molecules inhibit EGFR-TK activity and will aid development of EGFR-TK mutant targeted therapies.