Particular Subsets (particular + subset)

Distribution by Scientific Domains


Selected Abstracts


Overlap in bibliographic databases

JOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 12 2003
William W. Hood
Bibliographic databases contain surrogates to a particular subset of the complete set of literature; some databases are very narrow in their scope, while others are multidisciplinary. These databases overlap in their coverage of the literature to a greater or lesser extent. The topic of Fuzzy Set Theory is examined to determine the overlap of coverage in the databases that index this topic. It was found that about 63% of records in the data set are unique to only one database, and the remaining 37% are duplicated in from two to 12 different databases. The overlap distribution is found to conform to a Lotka-type plot. The records with maximum overlap are identified; however, further work is needed to determine the significance of the high level of overlap in these records. The unique records are plotted using a Bradford-type form of data presentation and are found to conform (visually) to a hyperbolic distribution. The extent and causes of intra-database duplication (records duplicated in the one database) are also examined. Finally, the overlap in the top databases in the dataset were examined, and a high correlation was found between overlapping records, and overlapping DIALOG OneSearch categories. [source]


State-space partition techniques for multiterminal flows in stochastic networks

NETWORKS: AN INTERNATIONAL JOURNAL, Issue 2 2006
Matthew S. Daly
Abstract This article develops state-space partition methods for computing performance measures for stochastic networks with demands between multiple pairs of nodes. The chief concern is the evaluation of the probability that there exist separate, noninteracting flows that satisfy all demands. This relates to the multiterminal maximum flow problem discussed in the classic article of Gomory and Hu. The network arcs are assumed to have independent, discrete random capacities. We refer to the probability that all demands can be satisfied as the network reliability (with the understanding that its definition is application dependent). In addition, we also consider the calculation of secondary measures, such as the probability that a particular subset of demands can be met, and the probability that a particular arc lies on a minimum cut. The evaluation of each of these probabilities is shown to be NP-hard. The proposed methods are based on an iterative partition of the system state space, with each iteration tightening the bounds on the measure of interest. This last property allows the design of increasingly efficient Monte Carlo sampling plans that yield substantially more precise estimators than the standard Monte Carlo method that draws samples from the original capacity distribution. © 2006 Wiley Periodicals, Inc. NETWORKS, Vol. 48(2), 90,111 2006 [source]


Periodontal diseases and health: Consensus Report of the Sixth European Workshop on Periodontology

JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 2008
Denis Kinane
Abstract Introduction: The remit of this group was to update the knowledge base on periodontal diseases and health. Material and Methods: The literature was systematically searched and critically reviewed in five specific topics. Results: Prevalence of periodontitis: The data suggest a trend towards a lower prevalence of periodontitis in recent years. Adverse pregnancy outcome: The findings indicate a likely association between periodontal disease and an increased risk of adverse pregnancy outcomes. There is no evidence that treating periodontal disease decreases the rate of adverse pregnancy outcomes. Prevalence and distribution of periodontal pathogens: Genetic analysis of bacteria has demonstrated an unanticipated diversity within species. Carriage rates and particular subsets of these species vary between ethnic groups. Few of these differences can be related to differences in disease prevalence. Diabetes mellitus: Evidence on the association supports the concept of increased severity but not extent of periodontitis in subjects with poorly controlled diabetes. It is inconclusive that periodontal treatment results in improved metabolic control. Cardiovascular diseases: Evidence suggests that having periodontitis contributes to the total infectious and inflammation burden and may contribute to cardiovascular events and stroke in susceptible subjects. The impact of periodontal therapy must be further investigated. [source]


Autoinduction and signal transduction in the regulation of staphylococcal virulence

MOLECULAR MICROBIOLOGY, Issue 6 2003
Richard P. Novick
Summary The accessory genes of Staphylococcus aureus, in-cluding those involved in pathogenesis, are controlled by a complex regulatory network that includes at least four two-component systems, one of which, agr, is a quorum sensor, an alternative sigma factor and a large set of transcription factors, including at least two of the superantigen genes, tst and seb. These regulatory genes are hypothesized to act in a time- and population density-dependent manner to integrate signals received from the external environment with the internal metabolic machinery of the cell, in order to achieve the production of particular subsets of accessory/virulence factors at the time and in quantities that are appropriate to the needs of the organism at any given location. From the standpoint of pathogenesis, the regulatory agenda is presumably tuned to particular sites in the host organism. To address this hypothesis, it will be necessary to understand in considerable detail the regulatory interactions among the organism's numerous controlling systems. This review is an attempt to integrate a large body of data into the beginnings of a model that will hopefully help to guide research towards a full-scale test. [source]


ORIGINAL ARTICLE: Leukocyte Activation and Circulating Leukocyte-Derived Microparticles in Preeclampsia

AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 5 2009
Christianne A.R. Lok
Problem, Preeclampsia shows characteristics of an inflammatory disease including leukocyte activation. Analyses of leukocyte-derived microparticles (MP) and mRNA expression of inflammation-related genes in leukocytes may establish which subgroups of leukocytes contribute to the development of preeclampsia. Method of Study, Blood samples were obtained from preeclamptic patients, normotensive pregnant and non-pregnant controls. sL-selectin and elastase were measured by ELISA. mRNA was isolated from leukocytes and gene expression was determined by multiplex ligation-dependent probe amplification (MLPA). MP were characterized by flow cytometry. Results, Altered concentrations of sL-selectin and elastase confirmed leukocyte activation in preeclampsia. These leukocytes showed up-regulation of Nuclear Factor of Kappa light chain gene enhancer in B Cells inhibitor (NF,B-1A) and cyclin-dependent kinase inhibitor (CDKN)-1A compared with normotensive pregnant women. interleukin-1 Receptor Antagonist (IL-1RA) and tumor necrosis factor (TNF)-R1 were increased compared with those in non-pregnant controls. Monocyte-derived MP were elevated in preeclamptic patients compared with pregnant women. The numbers of cytotoxic T-cell-derived and granulocyte-derived MP were elevated compared with those of non-pregnant women. Conclusion, Leukocytes are activated in preeclampsia. A pro-inflammatory gene expression profile is not prominent, although differences in mRNA expression can be detected. Increased levels of particular subsets of leukocyte-derived MP reflect activation of their parental cells in preeclampsia. [source]


The Absence of Phosphorylated Tyrosine Hydroxylase Expression in the Purkinje Cells of the Ataxic Mutant Pogo Mouse

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2006
N. S. Lee
Summary The pogo mouse is a new ataxic autosomal recessive mutant that arose in Korean wild mice (KJR/Mskist). Its ataxic phenotype includes difficulty in maintaining a normal posture and the inability to walk in a straight line. Several studies have reported that tyrosine hydroxylase (TH) is persistently ectopically expressed in particular subsets of Purkinje cells in a parasagittal banding pattern in several ataxic mutant mice, e.g. tottering alleles and pogo mice. In this present study, we examined the expression of an enzymatically active form of TH and phosphorylated TH at Ser40 (phospho-TH) by using immunohistochemistry and double immunofluorescence in the cerebellum of pogo mice. TH immunostaining appeared in some Purkinje cells in pogo, but in only a few of Purkinje cells of their heterozygous littermate controls. In all groups of mice, no phospho-TH immunoreactive Purkinje cells were observed in the cerebellum, although subsets of TH immunoreactive Purkinje cells were found in adjacent sections. This study suggests that TH expression in the Purkinje cells of pogo abnormally increases without activation of this enzyme by phosphorylation. This may mean that TH in the Purkinje cells of these mutants does not catalyse the conversion of tyrosine to l -DOPA, and is not related to catecholamine synthesis. [source]


Increased expression of the natural killer cell inhibitory receptor CD94/NKG2A and CD158b on circulating and lesional T cells in patients with chronic plaque psoriasis

BRITISH JOURNAL OF DERMATOLOGY, Issue 2 2006
Y.H. Liao
Summary Background, Psoriasis is a common inflammatory cutaneous disorder characterized by activated T-cell infiltration. T lymphocytes bearing natural killer cell receptors (NKRs) have been suggested to play an important role in the pathogenesis of psoriasis. However, the expression pattern of activating and inhibitory NKRs on T lymphocytes from psoriatic patients and its significance in psoriasis needs further study. Objectives, To investigate the pathogenesis of NKR-expressing T cells in psoriasis. Materials and methods, Thirty patients with chronic plaque psoriasis and 20 healthy controls were enrolled in this study. The immunophenotypic profiles of NKRs, including CD56, CD16 (activating NKRs), CD158a, CD158b, CD94 and NKG2A (inhibitory NKRs), were analysed in peripheral blood T lymphocytes, as well as psoriatic lesional infiltrating T cells, by triple-fluorescence flow cytometry. Results, A significant increase of inhibitory CD8+ CD158b+, CD4, CD8, CD158b+ and CD8+ CD94/NKG2A+ T cells was found in the peripheral blood of patients with psoriasis when compared with controls. Tissue-infiltrating T lymphocytes expressing inhibitory receptors CD158b, CD94 and NKG2A were found in psoriatic lesions. There was a significant positive correlation between the increased percentage of circulating CD8+ CD94/NKG2A+ T cells and the Psoriasis Area and Severity Index. Conclusions, In the present study, we demonstrated increased proportions of particular subsets of inhibitory CD158b+ and/or CD94/NKG2A+ T cells in patients with psoriasis. The elevation of these inhibitory NKR-expressing T cells was correlated with disease severity, which may signify the possibility of chronic antigen-driven stimulation and dysregulated cytokine production in the pathogenesis of psoriasis. [source]


Bullous pemphigoid antigen II (BP180) and its soluble extracellular domains are major autoantigens in mucous membrane pemphigoid: the pathogenic relevance to HLA class II alleles and disease severity

BRITISH JOURNAL OF DERMATOLOGY, Issue 1 2006
N. Oyama
Summary Background, Mucous membrane pemphigoid (MMP), a chronic autoimmune subepithelial blistering disease, is associated with circulating IgG and/or IgA autoantibodies against several basement membrane zone antigens. The heterogeneity of clinical presentation and diversity of target autoantigens have contributed to difficulties in characterizing this condition immunologically. Objectives, To analyse serum autoantibody profile and HLA class II alleles in MMP patients and to correlate this with the clinical presentation of disease. Methods, Well-defined subgroups consisting of 124 patients with MMP were examined for IgG and IgA reactivity with immunoblotting using human epidermal, dermal and placental amnion proteins. The results were further analysed on the basis of detailed clinical (sites of involvement and disease severity) and immunopathological criteria (immunofluorescence study and HLA class II alleles). Results, Immunoblot assay revealed that the majority of MMP patients had IgG (93 of 124, 75%) and/or IgA autoantibodies (63 of 124, 51%) to BP180 (including its soluble ectodomains, 120-kDa LAD-1 and 97-kDa LABD97 antigens). Other antigens targeted predominantly by IgG autoantibodies included: BP230 in 34 (27%), ,4 integrin in 26 (21%), and laminin 5 in three (2%). All the BP230+ sera and 23 (88%) ,4 integrin+ sera also reacted with at least one of the BP180 antigens. Over 85% of patients with reactivity to ,4 integrin had ocular involvement. In most cases of MMP, more severe clinical features were associated with antibody reactivity to multiple basement membrane zone antigens, as well as reactivity to multiple BP180 component antigens. Dual BP180/LAD-1 reactivity with IgG and IgA was associated with a more severe phenotype. In addition, the subset-dependent autoantibody reactivity correlated well with specific HLA class II alleles, DQB1*0301, DRB1*04 and DRB1*11. Conclusions, Our results confirmed that BP180 is a major autoantigen targeted by the sera of patients with MMP. The disease-prevalent HLA class II alleles and humoral autoimmune response against the particular subsets of antigenic epitope(s) within BP180 ectodomain may contribute to the clinicopathological significance and disease severity of MMP. [source]