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11.
Carla GS Saad Ana CM Ribeiro Julio CB Moraes Liliam Takayama Celio R Goncalves Marcelo B Rodrigues Ricardo M de Oliveira Clovis A Silva Eloisa Bonfa Rosa MR Pereira 《Arthritis research & therapy》2012,14(5):R216
Introduction
Sclerostin levels have been reported to be low in ankylosing spondylitis (AS), but there is no data regarding the possible role of this Wnt inhibitor during anti-tumor necrosis factor (TNF) therapy. The present study longitudinally evaluated sclerostin levels, inflammatory markers and bone mineral density (BMD) in AS patients under anti-TNF therapy.Methods
Thirty active AS patients were assessed at baseline, 6 and 12 months after anti-TNF therapy regarding clinical parameters, inflammatory markers, BMD and baseline radiographic damage (mSASSS). Thirty age- and sex-matched healthy individuals comprised the control group. Patients'' sclerostin levels, sclerostin binding low-density lipoprotein receptor-related protein 6 (LRP6) and BMD were evaluated at the same time points and compared to controls.Results
At baseline, AS patients had lower sclerostin levels (60.5 ± 32.7 vs. 96.7 ± 52.9 pmol/L, P = 0.002) and comparable sclerostin binding to LRP6 (P = 0.387) than controls. Improvement of Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), Bath Ankylosing Spondylitis Metrology Index (BASMI), Ankylosing Spondylitis quality of life (ASQoL) was observed at baseline vs. 6 vs. 12 months (P < 0.01). Concomitantly, a gradual increase in spine BMD (P < 0.001) and a positive correlation between baseline mSASSS and spine BMD was found (r = 0.468, P < 0.01). Inflammatory parameters reduction was observed comparing baseline vs. 6 vs. 12 months (P <0.01). Sclerostin levels progressively increased [baseline (60.5 ± 32.7) vs. 6 months (67.1 ± 31.9) vs. 12 months (72.7 ± 32.3) pmol/L, P <0.001]. At 12 months, the sclerostin levels remained significantly lower in patients compared to controls (72.7 ± 32.3 vs. 96.70 ± 52.85 pmol/L, P = 0.038). Moreover, sclerostin serum levels at 12 months were lower in the 10 patients with high C reactive protein (CRP) (≥ 5 mg/l) compared to the other 20 patients with normal CRP (P = 0.004). Of note, these 10 patients with persistent inflammation also had lower sclerostin serum levels at baseline compared to the other patients (P = 0.023). Univariate logistic regression analysis demonstrated that AS patients with lower sclerostin serum levels had an increased risk to have high CRP at 12 months (odds ratio = 7.43, 95% CI 1.23 to 45.01, P = 0.020) than those with higher sclerostin values.Conclusions
Persistent low sclerostin levels may underlie continuous inflammation in AS patients under anti-TNF therapy. 相似文献12.
13.
Anne-Christine Bay-Jensen Nadine CB Tabassi Lene V Sondergaard Thomas L Andersen Frederik Dagnaes-Hansen Patrick Garnero Moustapha Kassem Jean-Marie Delaissé 《Arthritis research & therapy》2009,11(1):R9
Introduction
The urinary level of the type II collagen degradation marker CTX-II is increased in postmenopausal women and in ovariectomised rats, suggesting that oestrogen deprivation induces cartilage breakdown. Here we investigate whether this response to oestrogen is also true for other type II collagen turnover markers known to be affected in osteoarthritis, and whether it relates to its presence in specific areas of cartilage tissue. 相似文献14.
Male sagebrush crickets, Cyphoderris strepitans, offer an unusual nuptial food gift to females during copulation: females feed on the hindwings of males and ingest haemolymph seeping from the wounds they inflict. Previous work has shown that females prevented from wing feeding during initial copulations are more receptive to subsequent matings than females permitted to wing feed. In the present study, we tested the hypothesis that hormonal substances contained in the haemolymph of males, and ingested by females during copulation, function to decrease female receptivity to further matings. We tested this hypothesis by providing females, experimentally prevented from wing feeding, with male-derived haemolymph or appropriate control substances (female-derived haemolymph or cricket Ringer's solution), and recording their propensity to mate (in 1999) or remate (in 2000). Female mating propensity was not affected by ingestion of male haemolymph in either experiment. Although these results are inconsistent with the male manipulation hypothesis, it is possible that putative receptivity-inhibiting substances are sequestered in the integument of males' hindwings, rather than contained in male haemolymph per se. Alternatively, both the results of the present study and those of previous studies are consistent with the hypothesis that wing feeding leads simply to satiation of females, and thereby diminishes their motivation to seek out additional matings. Copyright 2003 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved. 相似文献
15.
We examined a novel hypothesis for the maintenance of communal nesting in the salamander, Hemidactylium scutatum, namely that communal nests are more likely than solitary nests to be associated with cutaneous antifungal bacteria, which
can inhibit fungal infections of embryos. A communal nest contains eggs of two or more females of the same species. The nesting
behavior of H. scutatum females and survival of embryos were determined by frequent nest surveys at three ponds. For communal nests, embryonic survival
tended to be higher and catastrophic nest failure was lower. Pure bacterial cultures of resident species were obtained from
the salamanders’ skins by swabbing and tested against a fungal pathogen of embryos (Mariannaea sp.) in laboratory assays. We found that 27% of females had skin bacteria inhibitory to Mariannaea sp. Communal nests were more likely to have at least one female with antifungal bacteria than were solitary nests. Using
a culture-independent assay (denaturing gradient gel electrophoresis of 16S rRNA gene fragments), we found that bacterial
species on females and embryos were more similar to each other than they were to bacterial species found in soil within the
nest, suggesting that females transmitted skin bacteria to embryos. The presence of anti-Mariannaea skin bacteria identified from the laboratory assays did not prevent fungal presence in field nests. However, once a nest
was visibly infected with fungi, presence of anti-Mariannaea bacteria was positively correlated with survival of embryos. Microbe transmission is usually thought to be a cost of group
living, but communal nesting in H. scutatum may facilitate the transmission of antifungal bacteria to embryos. 相似文献
16.
Female choice for male cuticular hydrocarbon profile in decorated crickets is not based on similarity to their own profile
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S. Steiger A. Capodeanu‐Nägler S. N. Gershman C. B. Weddle J. Rapkin S. K. Sakaluk J. Hunt 《Journal of evolutionary biology》2015,28(12):2175-2186
Indirect genetic benefits derived from female mate choice comprise additive (good genes) and nonadditive genetic benefits (genetic compatibility). Although good genes can be revealed by condition‐dependent display traits, the mechanism by which compatibility alleles are detected is unclear because evaluation of the genetic similarity of a prospective mate requires the female to assess the genotype of the male and compare it to her own. Cuticular hydrocarbons (CHCs), lipids coating the exoskeleton of most insects, influence female mate choice in a number of species and offer a way for females to assess genetic similarity of prospective mates. Here, we determine whether female mate choice in decorated crickets is based on male CHCs and whether it is influenced by females' own CHC profiles. We used multivariate selection analysis to estimate the strength and form of selection acting on male CHCs through female mate choice, and employed different measures of multivariate dissimilarity to determine whether a female's preference for male CHCs is based on similarity to her own CHC profile. Female mating preferences were significantly influenced by CHC profiles of males. Male CHC attractiveness was not, however, contingent on the CHC profile of the choosing female, as certain male CHC phenotypes were equally attractive to most females, evidenced by significant linear and stabilizing selection gradients. These results suggest that additive genetic benefits, rather than nonadditive genetic benefits, accrue to female mate choice, in support of earlier work showing that CHC expression of males, but not females, is condition dependent. 相似文献
17.
Background
State-of-the-art signal processing methods are known to detect information in single-trial event-related EEG data, a crucial aspect in development of real-time applications such as brain computer interfaces. This paper investigates one such novel approach, evaluating how individual classifier and feature subset tailoring affects classification of single-trial EEG finger movements. The discrete wavelet transform was used to extract signal features that were classified using linear regression and non-linear neural network models, which were trained and architecturally optimized with evolutionary algorithms. The input feature subsets were also allowed to evolve, thus performing feature selection in a wrapper fashion. Filter approaches were implemented as well by limiting the degree of optimization. 相似文献18.
Carie B. Weddle Sandra Steiger Christopher G. Hamaker Geoffrey D. Ower Christopher Mitchell Scott K. Sakaluk John Hunt 《Ecology letters》2013,16(3):346-353
Females of many species obtain benefits by mating polyandrously, and often prefer novel males over previous mates. However, how do females recognise previous mates, particularly in the face of cognitive constraints? Female crickets appear to have evolved a simple but effective solution: females imbue males with their own cuticular hydrocarbons (CHCs) at mating and utilise chemosensory self‐referencing to recognise recent mates. Female CHC profiles exhibited significant additive genetic variation, demonstrating that genetically unique chemical cues are available to support chemosensory self‐referencing. CHC profiles of males became more similar to those of females after mating, indicating physical transfer of CHCs between individuals during copulation. Experimental perfuming of males with female CHCs resulted in a female aversion to males bearing chemical cues similar to their own. Chemosensory self‐referencing, therefore, could be a widespread mechanism by which females increase the diversity of their mating partners. 相似文献
19.
Daniel CB Jeffery Naoko Kakusho Zhiying You Marlene Gharib Brandon Wyse Erin Drury Michael Weinreich Pierre Thibault Alain Verreault Hisao Masai Krassimir Yankulov 《Cell cycle (Georgetown, Tex.)》2015,14(1):74-85
Chromatin Assembly Factor I (CAF-I) plays a key role in the replication-coupled assembly
of nucleosomes. It is expected that its function is linked to the regulation of the cell
cycle, but little detail is available. Current models suggest that CAF-I is recruited to
replication forks and to chromatin via an interaction between its Cac1p subunit and the
replication sliding clamp, PCNA, and that this interaction is stimulated by the kinase
CDC7. Here we show that another kinase, CDC28,
phosphorylates Cac1p on serines 94 and 515 in early S phase and regulates its association
with chromatin, but not its association with PCNA. Mutations in the Cac1p-phosphorylation
sites of CDC28 but not of CDC7 substantially reduce the
in vivo phosphorylation of Cac1p. However, mutations in the putative
CDC7 target sites on Cac1p reduce its stability. The association of
CAF-I with chromatin is impaired in a cdc28–1 mutant and to a
lesser extent in a cdc7–1 mutant. In addition, mutations in the
Cac1p-phosphorylation sites by both CDC28 and CDC7
reduce gene silencing at the telomeres. We propose that this phosphorylation represents a
regulatory step in the recruitment of CAF-I to chromatin in early S phase that is distinct
from the association of CAF-I with PCNA. Hence, we implicate CDC28 in the
regulation of chromatin reassembly during DNA replication. These findings provide novel
mechanistic insights on the links between cell-cycle regulation, DNA replication and
chromatin reassembly. 相似文献
20.
Two contrasting approaches have been used to construct the overall tree of life from molecular data: one involves the analysis of single large datasets, while the other involves joining many independent smaller analyses into a supertree. A recent study uses the latter approach to produce the most complete phylogeny yet of flowering plant families. 相似文献