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41.
42.
Melek Güler-Yüksel Naomi B Klarenbeek Yvonne PM Goekoop-Ruiterman Jeska K de Vries-Bouwstra Sjoerd M van der Kooij Andreas H Gerards H Karel Ronday Tom WJ Huizinga Ben AC Dijkmans Cornelia F Allaart Willem F Lems 《Arthritis research & therapy》2010,12(3):R96
Introduction
To investigate whether accelerated hand bone mineral density (BMD) loss is associated with progressive joint damage in hands and feet in the first year of rheumatoid arthritis (RA) and whether it is an independent predictor of subsequent progressive total joint damage after 4 years.Methods
In 256 recent-onset RA patients, baseline and 1-year hand BMD was measured in metacarpals 2-4 by digital X-ray radiogrammetry. Joint damage in hands and feet were scored in random order according to the Sharp-van der Heijde method at baseline and yearly up to 4 years.Results
68% of the patients had accelerated hand BMD loss (>-0.003 g/cm2) in the first year of RA. Hand BMD loss was associated with progressive joint damage after 1 year both in hands and feet with odds ratios (OR) (95% confidence intervals [CI]) of 5.3 (1.3-20.9) and 3.1 (1.0-9.7). In univariate analysis, hand BMD loss in the first year was a predictor of subsequent progressive total joint damage after 4 years with an OR (95% CI) of 3.1 (1.3-7.6). Multivariate analysis showed that only progressive joint damage in the first year and anti-citrullinated protein antibody positivity were independent predictors of long-term progressive joint damage.Conclusions
In the first year of RA, accelerated hand BMD loss is associated with progressive joint damage in both hands and feet. Hand BMD loss in the first year of recent-onset RA predicts subsequent progressive total joint damage, however not independent of progressive joint damage in the first year. 相似文献43.
44.
Gutkowska J Paquette A Wang D Lavoie JM Jankowski M 《American journal of physiology. Regulatory, integrative and comparative physiology》2007,293(1):R267-R275
Exercise training results in cardiovascular and metabolic adaptations that may be beneficial in menopausal women by reducing blood pressure, insulin resistance, and cholesterol level. The adaptation of the cardiac hormonal systems oxytocin (OT), natriuretic peptides (NPs), and nitric oxide synthase (NOS) in response to exercise training was investigated in intact and ovariectomized (OVX) rats. Ovariectomy significantly augmented body weight (BW), left ventricle (LV) mass, and intra-abdominal fat pad weight and decreased the expression of oxytocin receptor (OTR), atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and guanylyl cyclase-A (GC-A), in the right atrium (RA) and LV, indicating estrogenic control of these genes. These effects of ovariectomy were counteracted by 8-wk-long exercise training which decreased fat pad weight (33.4 +/- 2.3 to 23.4 +/- 3.1 g, n = 8, P < 0.05), plasma free fatty acids (0.124 +/- 0.033 to 0.057 +/- 0.010 mM, n = 8, P < 0.01), and plasma triacylglycerol (0.978 +/- 0.174 to 0.588 +/- 0.115 mM, n = 8, P < 0.05). Chronic exercise tended to decrease BW and stimulated ANP (4- to 5-fold) and OTR gene expression in the LV and RA and BNP and inducible NOS (iNOS) mRNA in the LV. In sham-operated rats, exercise augmented ANP expression in the RA, downregulated GC-A mRNA in the LV and RA, but increased its expression threefold in the RA of OVX animals. Endothelial NOS and iNOS expression was enhanced in the left atrium of sham-operated rats. Altogether, these data indicate that in OVX animals, chronic exercise significantly enhances cardiac OT, NPs, and NOS, thus implicating all three hormonal systems in the beneficial effects of exercise training. 相似文献
45.
Sulsky R Magnin DR Huang Y Simpkins L Taunk P Patel M Zhu Y Stouch TR Bassolino-Klimas D Parker R Harrity T Stoffel R Taylor DS Lavoie TB Kish K Jacobson BL Sheriff S Adam LP Ewing WR Robl JA 《Bioorganic & medicinal chemistry letters》2007,17(12):3511-3515
Herein we report the first disclosure of biphenyl azoles that are nanomolar binders of adipocyte fatty acid binding protein (aFABP or aP2) with up to thousand-fold selectivity against muscle fatty acid binding protein and epidermal fatty acid binding protein. In addition a new radio-ligand to determine binding against the three fatty acid binding proteins was also synthesized. 相似文献
46.
Christian Lavoie C. Josh Donlan Karl Campbell Felipe Cruz G. Victor Carrion 《Biological invasions》2007,9(2):139-148
Non-native mammals are major drivers of ecosystem change and biodiversity loss; this is especially apparent on islands. However,
techniques exist to remove non-native mammals, providing a powerful conservation tool. Conservation practitioners are now
targeting larger islands for restoration. Leveraging existing and developing new techniques and technologies will prove critical
to successful eradications on large islands. Using the removal of introduced goats (Capra hircus) from Santiago Island, Galápagos as a case study, we present a suite of Geographic Information System (GIS) tools that aid
island conservation actions. GIS tools were incorporated into the three phases of the eradication campaign: planning, hunting,
and monitoring. Further, these tools were adopted for three eradication techniques: ground-based hunting, aerial hunting by
helicopter, and Judas goats. These geographic approaches provide a foundation for statistical, spatial, and economic analyses
that should increase the capability and efficiency of removal campaigns. Given limited conservation funds and the dire status
of many insular species, efficiently removing non-native mammals from islands is of paramount global conservation importance. 相似文献
47.
Paulo FP Pimenta Alessandra S Orfano Ana C Bahia Ana PM Duarte Claudia M Ríos-Velásquez Fabrício F Melo Felipe AC Pessoa Giselle A Oliveira Keillen MM Campos Luis Martínez Villegas Nilton Barnabé Rodrigues Rafael Nacif-Pimenta Rejane C Sim?es Wuelton M Monteiro Rogerio Amino Yara M Traub-Cseko José BP Lima Maria GV Barbosa Marcus VG Lacerda Wanderli P Tadei Nágila FC Secundino 《Memórias do Instituto Oswaldo Cruz》2015,110(1):23-47
In the Americas, areas with a high risk of malaria transmission are mainly located in
the Amazon Forest, which extends across nine countries. One keystone step to
understanding the Plasmodium life cycle in Anopheles species from the Amazon Region
is to obtain experimentally infected mosquito vectors. Several attempts to colonise
Ano- pheles species have been conducted, but with only short-lived success or no
success at all. In this review, we review the literature on malaria transmission from
the perspective of its Amazon vectors. Currently, it is possible to develop
experimental Plasmodium vivax infection of the colonised and field-captured vectors
in laboratories located close to Amazonian endemic areas. We are also reviewing
studies related to the immune response to P. vivax infection of Anopheles aquasalis,
a coastal mosquito species. Finally, we discuss the importance of the modulation of
Plasmodium infection by the vector microbiota and also consider the anopheline
genomes. The establishment of experimental mosquito infections with Plasmodium
falciparum, Plasmodium yoelii and Plasmodium berghei parasites that could provide
interesting models for studying malaria in the Amazonian scenario is important.
Understanding the molecular mechanisms involved in the development of the parasites
in New World vectors is crucial in order to better determine the interaction process
and vectorial competence. 相似文献
48.
A preliminary experimental investigation of dry reforming of methane with carbon dioxide, that has been performed on an iron bed activated with an electric current is reported. Operating conditions for the reaction included temperature ranging from 700 to 800° C and pressure close to 1 atm. The reaction, involving an excess of pure methane and carbon dioxide, was performed with and without addition of water vapour, provided by hot water saturation of the gaseous feed. According to syngas compositions, the electron flow has a dramatic effect on the conversion of both methane and carbon dioxide. It was shown also that hot water saturation of the CO(2) and CH(4) mixture allowed very good conversion, giving a syngas with a composition very close to what was expected from equilibrium calculations. 相似文献
49.
Shinichiro Maruyama Toshinobu Suzaki Andreas PM Weber John M Archibald Hisayoshi Nozaki 《BMC evolutionary biology》2011,11(1):105
Background
Euglenophytes are a group of photosynthetic flagellates possessing a plastid derived from a green algal endosymbiont, which was incorporated into an ancestral host cell via secondary endosymbiosis. However, the impact of endosymbiosis on the euglenophyte nuclear genome is not fully understood due to its complex nature as a 'hybrid' of a non-photosynthetic host cell and a secondary endosymbiont. 相似文献50.
EBP2 plays a key role in Epstein-Barr virus mitotic segregation and is regulated by aurora family kinases
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Epstein-Barr virus (EBV) genomes persist indefinitely in latently infected human cells, in part due to their ability to stably segregate during cell division. This process is mediated by the viral EBNA1 protein, which tethers the viral episomes to the cellular mitotic chromosomes. We have previously identified a mitotic chromosomal protein, human EBNA1 binding protein 2 (hEBP2), which binds to EBNA1 and enables EBNA1 to partition EBV-based plasmids in Saccharomyces cerevisiae. Using an RNA silencing approach, we show that hEBP2 is essential for the proliferation of human cells and that repression of hEBP2 severely decreases the ability of EBNA1 and EBV-based plasmids to bind mitotic chromosomes. When expressed in yeast, hEBP2 undergoes the same cell cycle-regulated association with the mitotic chromatin as in human cells, and using yeast temperature-sensitive mutant strains, we found that the attachment of hEBP2 to mitotic chromosomes was dependent on the Ipl1 kinase. Both RNA silencing of the Ipl1 orthologue in human cells (Aurora B) and specific inhibition of the Aurora B kinase activity with a small molecule confirmed a role for this kinase in enabling hEBP2 binding to human mitotic chromosomes, suggesting that this kinase can regulate EBV segregation. 相似文献