Key Members (key + member)

Distribution by Scientific Domains

Selected Abstracts

A pyrene-degrading consortium from deep-sea sediment of the West Pacific and its key member Cycloclasticus sp.


Summary A pyrene-degrading bacterial consortium was obtained from deep-sea sediments of the Pacific Ocean. The consortium degraded many kinds of polycyclic aromatic hydrocarbons (PAHs), including naphthalene, phenanthrene, pyrene, acenaphthene, fluorene, anthracene, fluoranthene, 2-methylnaphthalene and 2,6-dimethylnaphthalene, but it did not grow with chrysene and benzo[,]pyrene. With methods of plate cultivation and polymerase chain reaction,denaturing gradient gel electrophoresis (PCR-DGGE), 72 bacteria belonging to 22 genera were detected from this consortium. Among the detected bacteria, the following genera frequently occurred: Flavobacterium, Cycloclasticus, Novosphingobium, Halomonas, Achromobacter, Roseovarius and Alcanivorax. The first two genera showed the strongest bands in denaturing gradient gel electrophoresis (DGGE) profiles and appeared in all PAH treatments. By now, only one isolate designated P1 was confirmed to be a pyrene degrader. It was identified to be Cycloclasticus spirillensus (100%). Although P1 can degrade pyrene independently, other bacteria, such as Novosphingobium sp. (Band 14), Halomonas sp. (Band 16) and an unidentified bacterium (Band 35), were involved in pyrene degradation in some way; they persist in the consortium in the test of dilution to extinction if only the consortium was motivated with pyrene. However, the secondary most important member Flavobacterium sp. evaded from the community at high dilutions. As a key member of the consortium, P1 distinguished itself by both cell morphology and carbon source range among the isolates of this genus. Based on intermediate analyses of pyrene degradation, P1 was supposed to take an upper pathway different from that previously reported. Together with the results of obtained genes from P1 homology with those responsible for naphthalene degradation, its degradation to pyrene is supposed to adopt another set of genes unique to presently detected. Summarily, an efficient pyrene-degrading consortium was obtained from the Pacific Ocean sediment, in which Cycloclasticus bacterium played a key role. This is the first report to exploit the diversity of pyrene-degrading bacteria in oceanic environments. [source]

,-Arrestin 2 regulates toll-like receptor 4-mediated apoptotic signalling through glycogen synthase kinase-3,

IMMUNOLOGY, Issue 4 2010
Hui Li
Summary Toll-like receptor 4 (TLR4), a key member of the TLR family, has been well characterized by its function in the induction of inflammatory products of innate immunity. However, the involvement of TLR4 in a variety of apoptotic events by an unknown mechanism has been the focus of great interest. Our investigation found that TLR4 promoted apoptotic signalling by affecting the glycogen synthase kinase-3, (GSK-3,) pathway in a serum-deprivation-induced apoptotic paradigm. Serum deprivation induces GSK-3, activation in a pathway that leads to subsequent cell apoptosis. Intriguingly, this apoptotic cascade is amplified in presence of TLR4 but greatly attenuated by ,-arrestin 2, another critical molecule implicated in TLR4-mediated immune responses. Our data suggest that the association of ,-arrestin 2 with GSK-3, contributes to the stabilization of phospho-GSK-3,, an inactive form of GSK-3,. It becomes a critical determinant for the attenuation of TLR4-initiated apoptosis by ,-arrestin 2. Taken together, we demonstrate that the TLR4 possesses the capability of accelerating GSK-3, activation thereby deteriorating serum-deprivation-induced apoptosis; ,-arrestin 2 represents an inhibitory effect on the TLR4-mediated apoptotic cascade, through controlling the homeostasis of activation and inactivation of GSK-3,. [source]

Ptc, Smo, Sufu, and the Hedgehog signaling pathway in amphioxus

Yushuang Lin
SUMMARY The Hedgehog (Hh) signaling pathway regulates many developmental processes both in vertebrates and in invertebrates. However, little is known about this pathway in the cephalochordate amphioxus. In this paper, we focus on the Ptc, Smo, and Sufu homologs in amphioxus, which are the key members of the Hh signaling pathway. Their genomic structures show their comparability with homologs in vertebrates. In situ hybridization reveals that amphioxus Ptc, Smo, and Sufu have similar expression patterns in embryogenesis. They are expressed in the neural plate at early neurula stage, and then down-regulated in dorsal neural ectoderm. During development, their transcripts appear and persist in the notochord, the wall of the head cavity, the epithelium of the pharynx, and the gut. The data show that the expression patterns of these three genes are overlapping with Hh and Gli during the embryonic development in amphioxus. Moreover, injection of amphioxus Hh RNA into zebrafish-fertilized eggs can expand the expression domains of Ptc1 and Nk2.2a, the target genes of the Hh signaling pathway, which is similar to the injection of zebrafish Sonic hh a (zShha) and Sonic hh b (zShhb). Our results suggest that amphioxus may possess a conserved and functional Hh signaling pathway similar to that of vertebrates. [source]

An evolutionary transition of vasa regulation in echinoderms

Celina E. Juliano
SUMMARY Vasa, a DEAD box helicase, is a germline marker that may also function in multipotent cells. In the embryo of the sea urchin Strongylocentrotus purpuratus, Vasa protein is posttranscriptionally enriched in the small micromere lineage, which results from two asymmetric cleavage divisions early in development. The cells of this lineage are subsequently set aside during embryogenesis for use in constructing the adult rudiment. Although this mode of indirect development is prevalent among echinoderms, early asymmetric cleavage divisions are a derived feature in this phylum. The goal of this study is to explore how vasa is regulated in key members of the phylum with respect to the evolution of the micromere and small micromere lineages. We find that although striking similarities exist between the vasa mRNA expression patterns of several sea urchins and sea stars, the time frame of enriched protein expression differs significantly. These results suggest that a conserved mechanism of vasa regulation was shifted earlier in sea urchin embryogenesis with the derivation of micromeres. These data also shed light on the phenotype of a sea urchin embryo upon removal of the Vasa-positive micromeres, which appears to revert to a basal mechanism used by extant sea stars and pencil urchins to regulate Vasa protein accumulation. Furthermore, in all echinoderms tested here, Vasa protein and/or message is enriched in the larval coelomic pouches, the site of adult rudiment formation, thus suggesting a conserved role for vasa in undifferentiated multipotent cells set aside during embryogenesis for use in juvenile development. [source]

Persistence, Principle and Patriotism in the Making of the Union of 1707: The Revolution, Scottish Parliament and the squadrone volante

HISTORY, Issue 306 2007
Since the 1960s most historians of the Union of 1707 have considered it a less than glorious chapter in Scotland's history. Driven by ambition and greed, Scots politicians, covetous of English wealth and swayed by promises and bribes, bartered their nation's independence for personal gain. Those genuinely committed to political union were in a minority. The following article maintains that this interpretation is based on an essentially short-term approach to the subject. Concentrating on the worsening relations between Scotland and England in the years immediately preceding the Union gives a distorted impression of what was a more enduring concern. It suggests the Revolution of 1688,9 had a far greater impact on the politics of union than previously anticipated, with the religious and political freedoms it guaranteed shaping the beliefs of a large number of Scots MPs who sat in Parliament 1706,7, almost half of whom had been members of King William's Convention Parliament with a majority supporting union. Focusing on the squadrone volante, one of the two much-maligned Scots unionist parties , the article traces the ideological roots of its key members and illustrates the various factors that led them to endorse an incorporating union which offered security for presbyterianism and a solution to Scotland's economic underdevelopment. Not denying that management and ambition played a significant part in securing the Union, it highlights the fact that amongst the Scottish political elite there was also a degree of genuine commitment and principled support. [source]

TGFB1 and TGFBR1 polymorphic variants in relationship to bladder cancer risk and prognosis

Adela Castillejo
Abstract The transforming growth factor-beta (TGF-,) signalling pathway plays an important role in tumor development and progression. We aimed at analyzing whether 7 different common variants in genes coding for 2 key members of the TGF-, signalling pathway (TGFB1 and TGFBR1) are associated with bladder cancer risk and prognosis. A total of 1,157 cases with urothelial cell carcinoma of the bladder and 1,157 matched controls where genotyped for 3 single nucleotide polymorphisms (SNPs) in TGFB1 (rs1982073, rs1800472, rs1800471) and an additional 3 SNPs and 1 indel polymorphism in TGFBR1 (rs868, rs928180, rs334358 and rs11466445, respectively). In the case-control study, we estimated odds ratios and 95% confidence intervals for each individual genetic variant using unconditional logistic regression adjusting for age, gender, study area and smoking status. Survival analysis was performed using the Kaplan-Meier method and Cox models. The endpoints of interest were tumor relapse, progression and death from bladder cancer. All the SNPs analyzed showed a similar distribution among cases and controls. The distribution of the TGFBR1*6A allele (rs11466445) was also similar among cases and controls, indicating no association with bladder cancer risk. Similarly, none of the haplotypes was significantly associated with bladder cancer risk. Among patients with muscle-invasive tumors, we found a significant association between TGFBR1- rs868 and disease-specific mortality with an allele dosage effect (p -trend = 0.003). In conclusion, the genetic variants analyzed were not associated with an increased risk of bladder cancer. The association of TGFBR1- rs868 with outcome should be validated in independent patient series. 2008 Wiley-Liss, Inc. [source]

Curriculum reform: a narrated journey

Geraldine MacCarrick
Objectives, Curriculum reform poses significant challenges for medical schools across the globe. Understanding the medical educator's personal and lived experience of curriculum change is paramount. This paper illustrates the use of narrative inquiry as a means of exploring the author's own evolving professional identity as a medical educator engaged in planning and leading curriculum reform and in understanding the meanings she and other medical educators attribute to their roles as agents of change in a medical school. Context, In 2002 it was decided to radically reform a school of medicine's (SoM) traditional 6-year medical degree course (converting it to a 5-year, integrated, case-based programme). This followed a decade of adverse external reports by the national accreditation agency. The 2001 accreditation report was the most significant catalyst for change, and drew attention to the School's need for a ,collective will' to introduce a series of specific curriculum reforms. To support this reform, a new curriculum working group (NCWG) supported by a dedicated medical education unit (MEU) was established. In late 2002 the author joined the School as the director of that unit. Methods, This paper draws on a 3-year study which captured the stories of the curriculum planning project between 2002 and 2005, as well as stories of curriculum reform from past deans of the same medical school dating back to 1965. Narrative inquiry is used as a means of probing the author's own lived experience as coordinator of the new curriculum project and the experiences of key members of the NCWG, including the dean, and of former deans from the same medical school over its 40-year history. Conclusions, Through a living, telling and retelling of the story of curriculum change, narrative inquiry has a role to play in both elucidating the individual lived experience of curriculum change and shaping the evolving professional identity of the medical educator as an agent of change. [source]

Developing multidisciplinary guidelines for the management of early rheumatoid arthritis

BA Hons, Sheena Hennell RGN
Abstract Objective:,To develop an evidence based guideline, for the multidisciplinary management of early rheumatoid arthritis (RA). Methods:,Recommendations were developed using both an evidence-based approach and expert opinion. The scientific committee, composed of key members of the rheumatology multidisciplinary team used a Delphi approach to evaluate topics and standard statements, which formed the basis for developing recommendations for management of RA in the first 2 years of disease. Evidence taken from literature was used to support these recommendations. Results:,24 evidence based recommendations for the management of early RA, with a grade of recommendation from A to C, were developed. In addition an algorithm of care was designed to promote a clear multidisciplinary management pathway. A mechanism for audit was also identified. Conclusion:,Involvement of the multidisciplinary rheumatology team has enabled a holistic guideline to be developed for the management of patients presenting with early RA. This guideline is based around best practice that is supported by published literature. Whilst most statements in the guideline are based on strong evidence, others have been formulated by expert consensus in the absence of data and should serve as an opportunity to improve current practice through future research and audit. The development and implementation of such a guideline should improve the care of patients with early RA. Copyright 2007 John Wiley & Sons, Ltd. [source]

Leading from Below: How Sub-National Governments Influence Policy Agendas

J.N. Keddie
This article takes a state's eye view of trends towards a more centralised system of governance in Australia. It argues that while globalisation strengthens the roles of national governments it also provides less noticed public policy and management opportunities for sub-national governments. The article shows how state governments in Australia can use high-level policy proposals to reinforce their continuing relevance as key members of a federal system of government. It proposes that skilful deployment of policy ideas and analyses can enable the states to sustain alternative national agendas despite hostility or lack of interest by the federal government. In conclusion, the article examines the implications for federal-state relations under the Rudd government. It suggests that the elements for productive reform agendas are present but that bringing them together will require considerable effort. [source]

The lifespan and life-cycle of self-help groups: a retrospective study of groups in Nottingham, UK

Sarah Chaudhary LLB (Hons) MA
Abstract This article is based on an analysis of a practice database held by Self Help Nottingham, an organisation that supports local self-help groups. The database contains details of 936 groups that closed between 1982 and 2007. The aim of the study is to provide qualitative and descriptive quantitative information about the life-cycles of self-help groups, the problems that they face throughout their existence and the likelihood of different problems leading to their closure. The database was not collated for research purposes and so we restrict our discussion of the findings to identification of broad patterns regarding the birth and closure rates of different types of group and questions for future research. Comparisons were made between groups that addressed different types of problem, groups with different memberships and groups that had reached different stages in their existence. There was reasonable consistency in the survival rates of different types of group with physical health groups being the most likely to reach maturity followed by mental health and lastly social issue groups. Survival rates for groups that serve different membership populations were reasonably constant although there were some anomalies. There were high levels of consistency regarding the reasons for closure for groups closing at different stages of maturity. The most commonly cited reasons among all groups were the withdrawal of a ,key' member and a decline in membership. The article suggests that some of the assumptions and prescriptions within the existing literature need to be considered in light of more detailed empirical evidence, and it raises questions about the theoretical understanding of self-help groups. [source]