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131.

Introduction

Adipokines such as adiponectin, leptin, and visfatin/nicotinamide phosphoribosyltransferase (NAMPT) have recently emerged as pro-inflammatory mediators involved in the pathophysiology of rheumatoid arthritis (RA). We aimed to determine whether serum adipokine levels independently predicted early radiographic disease progression in early RA.

Methods

In total, 791 patients were included from the prospective Etude et Suivi des POlyarthrites Indifférenciées Récentes (ESPOIR) cohort who met the American College of Rheumatology-European League Against Rheumatism criteria for RA (n = 632) or had undifferentiated arthritis (UA) (n = 159). Enzyme-linked immunosorbent assay (ELISA) was used to assess baseline serum levels of adiponectin, leptin, and visfatin/NAMPT. In the RA group, we tested the association of serum adipokine levels and (a) baseline radiographic damage and (b) radiographic disease progression, defined as a change >0 or ≥5 in total Sharp-van der Heijde Score (∆SHS) between inclusion and 1 year (∆SHS ≥1 or rapid radiographic progression: ∆SHS ≥5), adjusting for confounders (age, sex, body-mass index, insulin resistance, C-reactive protein level, Disease Activity Score in 28 joints, Health Assessment Questionnaire score, autoantibody status, steroid use, and radiographic evidence of RA damage at inclusion).

Results

Adiponectin level was independently associated with baseline total SHS (adjusted β = 0.12; P = 0.006). It was also associated with ∆SHS ≥1 (adjusted odds ratio (aOR) = 1.84 (1.25 to 2.72)) involving erosive as well as narrowing disease progression (aOR = 1.73 (1.17 to 2.55) and 1.93 (1.04 to 3.57), respectively). Serum adiponectin level predicted ∆SHS ≥5 (aOR = 2.0 (1.14 to 3.52)). Serum leptin level was independently associated only with ∆SHS >0 (aOR = 1.59 (1.05 to 2.42)). Conversely, serum visfatin/NAMPT level and radiographic disease progression were unrelated. Considering the receiver-operated characteristic curves, the best adiponectin cut-offs were 4.14 μg/ml for ∆SHS ≥1 and 6.04 μg/ml for ∆SHS ≥5, with a good specificity (58% and 75% for ∆SHS ≥1 and ∆SHS ≥5, respectively) and high negative predictive values (75% and 92% for ∆SHS ≥1 or ∆SHS ≥5, respectively).

Conclusion

Serum adiponectin level is a simple useful biomarker associated with early radiographic disease progression in early RA, independent of RA-confounding factors and metabolic status.  相似文献   
132.
A recent molecular phylogeny of the Arid clade of the genus Hemidactylus revealed that the recently described H. saba and two unnamed Hemidactylus species from Sinai, Saudi Arabia and Yemen form a well-supported monophyletic group within the Arabian radiation of the genus. The name ‘Hemidactylus saba species group’ is suggested for this clade. According to the results of morphological comparisons and the molecular analyses using two mitochondrial (12S and cytb) and four nuclear (cmos, mc1r, rag1, rag2) genes, the name Hemidactylus granosus Heyden, 1827 is resurrected from the synonymy of H. turcicus for the Sinai and Saudi Arabian species. The third species of this group from Yemen is described formally as a new species H. ulii sp. n. The phylogenetic relationships of the members of ‘Hemidactylus saba species group’ are evaluated and the distribution and ecology of individual species are discussed.  相似文献   
133.
The sensitivity analysis of a Cellular Genetic Algorithm (CGA) with local search is used to design a new and faster heuristic for the problem of mapping independent tasks to a distributed system (such as a computer cluster or grid) in order to minimize makespan (the time when the last task finishes). The proposed heuristic improves the previously known Min-Min heuristic. Moreover, the heuristic finds mappings of similar quality to the original CGA but in a significantly reduced runtime (1,000 faster). The proposed heuristic is evaluated across twelve different classes of scheduling instances. In addition, a proof of the energy-efficiency of the algorithm is provided. This convergence study suggests how additional energy reduction can be achieved by inserting low power computing nodes to the distributed computer system. Simulation results show that this approach reduces both energy consumption and makespan.  相似文献   
134.
135.
Event traces are helpful in understanding the performance behavior of parallel applications since they allow the in-depth analysis of communication and synchronization patterns. However, the absence of synchronized clocks on most cluster systems may render the analysis ineffective because inaccurate relative event timings may misrepresent the logical event order and lead to errors when quantifying the impact of certain behaviors or confuse the users of time-line visualization tools by showing messages flowing backward in time. In our earlier work, we have developed a scalable algorithm called the controlled logical clock that eliminates inconsistent inter-process timings postmortem in traces of pure MPI applications, potentially running on large processor configurations. In this paper, we first demonstrate that our algorithm also proves beneficial in computational grids, where a single application is executed using the combined computational power of several geographically dispersed clusters. Second, we present an extended version of the algorithm that—in addition to message-passing event semantics—also preserves and restores shared-memory event semantics, enabling the correction of traces from hybrid applications.  相似文献   
136.
137.
Background aimsGraft-versus-host disease (GVHD) is a life-threatening complication of allogeneic hematopoietic cell transplantation caused by donor T cells reacting against host tissues. Previous studies have suggested that mesenchymal stromal cells (MSCs) could exert potent immunosuppressive effects.MethodsThe ability of human bone marrow derived MSCs to prevent xenogeneic GVHD in non-obese diabetic/severe combined immunodeficient (NOD/SCID) mice and in NOD/SCID/interleukin-2Rγ(null) (NSG) mice transplanted with human peripheral blood mononuclear cells (PBMCs) was assessed.ResultsInjection of 200 × 106 human PBMCs intraperitoneally (IP) into sub-lethally (3.0 Gy) irradiated NOD/SCID mice also given anti-asialo GM1 antibodies IP 1 day prior and 8 days after transplantation induced lethal xenogeneic GVHD in all tested mice. Co-injection of 2 × 106 MSCs IP on day 0 did not prevent lethal xenogeneic GVHD induced by injection of human PBMCs. Similarly, injection of 30 × 106 human PBMCs IP into sub-lethally (2.5 Gy) irradiated NSG mice induced a lethal xenogeneic GVHD in all tested mice. Injection of 3 × 106 MSCs IP on days 0, 7, 14 and 21 did not prevent lethal xenogeneic GVHD induced by injection of human PBMCs.ConclusionsInjection of MSCs did not prevent xenogeneic GVHD in these two humanized mice models.  相似文献   
138.
ERCC1 (excision repair cross-complementation group 1) plays essential roles in the removal of DNA intrastrand crosslinks by nucleotide excision repair, and that of DNA interstrand crosslinks by the Fanconi anemia (FA) pathway and homology-directed repair processes (HDR). The function of ERCC1 thus impacts on the DNA damage response (DDR), particularly in anticancer therapy when DNA damaging agents are employed. ERCC1 expression has been proposed as a predictive biomarker of the response to platinum-based therapy. However, the assessment of ERCC1 expression in clinical samples is complicated by the existence of 4 functionally distinct protein isoforms, which differently impact on DDR. Here, we explored the functional competence of each ERCC1 protein isoform and obtained evidence that the 202 isoform is the sole one endowed with ERCC1 activity in DNA repair pathways. The ERCC1 isoform 202 interacts with RPA, XPA, and XPF, and XPF stability requires expression of the ERCC1 202 isoform (but none of the 3 others). ERCC1-deficient non-small cell lung cancer cells show abnormal mitosis, a phenotype reminiscent of the FA phenotype that can be rescued by isoform 202 only. Finally, we could not observe any dominant-negative interaction between ERCC1 isoforms. These data suggest that the selective assessment of the ERCC1 isoform 202 in clinical samples should accurately reflect the DDR-related activity of the gene and hence constitute a useful biomarker for customizing anticancer therapies.  相似文献   
139.

Background

In Chad, several species of tsetse flies (Genus: Glossina ) transmit African animal trypanosomoses (AAT), which represents a major obstacle to cattle rearing, and sleeping sickness, which impacts public health. After the failure of past interventions to eradicate tsetse, the government of Chad is now looking for other approaches that integrate cost-effective intervention techniques, which can be applied by the stake holders to control tsetse-transmitted trypanosomoses in a sustainable manner. The present study thus attempted to assess the efficacy of restricted application of insecticides to cattle leg extremities using footbaths for controlling Glossina m. submorsitans, G . tachinoides and G . f . fuscipes in southern Chad.

Methodology/Principal Findings

Two sites were included, one close to the historical human African trypanosomiasis (HAT) focus of Moundou and the other to the active foci of Bodo and Moissala. At both sites, a treated and an untreated herd were compared. In the treatment sites, cattle were treated on a regular basis using a formulation of deltamethrin 0.005% (67 to 98 cattle were treated in one of the sites and 88 to 102 in the other one). For each herd, tsetse densities were monthly monitored using 7 biconical traps set along the river and beside the cattle pen from February to December 2009. The impact of footbath treatment on tsetse populations was strong (p < 10-3) with a reduction of 80% in total tsetse catches by the end of the 6-month footbath treatment.

Conclusions/Significance

The impact of footbath treatment as a vector control tool within an integrated strategy to manage AAT and HAT is discussed in the framework of the “One Health” concept. Like other techniques based on the treatment of cattle, this technology should be used under controlled conditions, in order to avoid the development of insecticide and acaricide resistance in tsetse and tick populations, respectively.  相似文献   
140.
Predicting accurate fragments from sequence has recently become a critical step for protein structure modeling, as protein fragment assembly techniques are presently among the most efficient approaches for de novo prediction. A key step in these approaches is, given the sequence of a protein to model, the identification of relevant fragments - candidate fragments - from a collection of the available 3D structures. These fragments can then be assembled to produce a model of the complete structure of the protein of interest. The search for candidate fragments is classically achieved by considering local sequence similarity using profile comparison, or threading approaches. In the present study, we introduce a new profile comparison approach that, instead of using amino acid profiles, is based on the use of predicted structural alphabet profiles, where structural alphabet profiles contain information related to the 3D local shapes associated with the sequences. We show that structural alphabet profile-profile comparison can be used efficiently to retrieve accurate structural fragments, and we introduce a fully new protocol for the detection of candidate fragments. It identifies fragments specific of each position of the sequence and of size varying between 6 and 27 amino-acids. We find it outperforms present state of the art approaches in terms (i) of the accuracy of the fragments identified, (ii) the rate of true positives identified, while having a high coverage score. We illustrate the relevance of the approach on complete target sets of the two previous Critical Assessment of Techniques for Protein Structure Prediction (CASP) rounds 9 and 10. A web server for the approach is freely available at http://bioserv.rpbs.univ-paris-diderot.fr/SAFrag.  相似文献   
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