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61.
T Williams E Walz AR Lane M Pebole AC Hackney 《Biology of sport / Institute of Sport》2015,32(3):193-198
This study assessed the influence of estrogen (E2) on muscle damage biomarkers [skeletal muscle - creatine kinase (CK); cardiac muscle - CK-MB] responses to prolonged aerobic exercise. Eumenorrheic women (n=10) who were physically active completed two 60-minute treadmill running sessions at ∼60-65% maximal intensity during low E2 (midfollicular menstrual phase) and high E2 (midluteal menstrual phase) hormonal conditions. Blood samples were collected prior to exercise (following supine rest), immediately post-, 30 min post-, and 24 hours post-exercise to determine changes in muscle biomarkers. Resting blood samples confirmed appropriate E2 hormonal levels Total CK concentrations increased following exercise and at 24 hours post-exercise were higher in the midfollicular low E2 phase (p<0.001). However, CK-MB concentrations were unaffected by E2 level or exercise (p=0.442) resulting in the ratio of CK-MB to total CK being consistently low in subject responses (i.e., indicative of skeletal muscle damage). Elevated E2 levels reduce the CK responses of skeletal muscle, but had no effect on CK-MB responses following prolonged aerobic exercise. These findings support earlier work showing elevated E2 is protective of skeletal muscle from exercise-induced damage associated with prolonged aerobic exercise. 相似文献
62.
Geraldine AC Lim Erica G Jewell Xi Li Timothy A Erwin Christopher Love Jacqueline Batley German Spangenberg David Edwards 《BMC plant biology》2007,7(1):40
Background
Molecular genetic maps provide a means to link heritable traits with underlying genome sequence variation. Several genetic maps have been constructed for Brassica species, yet to date, there has been no simple means to compare this information or to associate mapped traits with the genome sequence of the related model plant, Arabidopsis. 相似文献63.
Irene EM Bultink D?rte Hamann Marc A Seelen Margreet H Hart Ben AC Dijkmans Mohamed R Daha Alexandre E Voskuyl 《Arthritis research & therapy》2007,8(6):R183
Infection imposes a serious burden on patients with systemic lupus erythematosus (SLE). The increased infection rate in SLE
patients has been attributed in part to defects of immune defence. Recently, the lectin pathway of complement activation has
also been suggested to play a role in the occurrence of infections in SLE. In previous studies, SLE patients homozygous for
mannose-binding lectin (MBL) variant alleles were at an increased risk of acquiring serious infections in comparison with
patients who were heterozygous or homozygous for the normal allele. This association suggests a correlation between functional
MBL level and occurrence of infections in SLE patients. We therefore investigated the biological activity of MBL and its relationship
with the occurrence of infections in patients with SLE. Demographic and clinical data were collected in 103 patients with
SLE. Functional MBL serum levels and MBL-induced C4 deposition were measured by enzyme-linked immunosorbent assay using mannan
as coat and an MBL- or C4b-specific monoclonal antibody. The complete MBL-dependent pathway activity was determined by using
an assay that measures the complete MBL pathway activity in serum, starting with binding of MBL to mannan, and was detected
with a specific monoclonal antibody against C5b-9. Charts were systematically reviewed to obtain information on documented
infections since diagnosis of SLE. Major infections were defined as infections requiring hospital admission and intravenous
administration of antibiotics. In total, 115 infections since diagnosis of lupus, including 42 major infections, were documented
in the 103 SLE patients (mean age 41 ± 13 years, mean disease duration 7 ± 4 years). The percentage of SLE patients with severe
MBL deficiency was similar to that in 100 healthy controls: 13% versus 14%, respectively. Although deposition of C4 to mannan
and MBL pathway activity were reduced in 21% and 43% of 103 SLE patients, respectively, neither functional MBL serum levels
nor MBL pathway activity was associated with infections or major infections in regression analyses. In conclusion, SLE patients
frequently suffer from infections, but deficiency of functional MBL does not confer additional risk. 相似文献
64.
Berry DC O'Byrne SM Vreeland AC Blaner WS Noy N 《Molecular and cellular biology》2012,32(15):3164-3175
The plasma membrane protein STRA6 transports vitamin A from its blood carrier retinol binding protein (RBP) into cells, and it also functions as a cytokine receptor which activates JAK/STAT signaling. We show here that, unlike other cytokine receptors, phosphorylation of STRA6 is not simply induced upon binding of its extracellular ligand. Instead, activation of the receptor is triggered by STRA6-mediated translocation of retinol from serum RBP to an intracellular acceptor, the retinol-binding protein CRBP-I. The observations also demonstrate that the movement of retinol from RBP to CRBP-I, and thus activation of STRA6, is critically linked to the intracellular metabolism of the vitamin. Furthermore, the data show that STRA6 phosphorylation is required for retinol uptake to proceed. Hence, the observations demonstrate that STRA6 orchestrates a multicomponent "machinery" that couples vitamin A homeostasis and metabolism to activation of a signaling cascade and that, in turn, STRA6 signaling regulates the cellular uptake of the vitamin. STRA6 appears to be a founding member of a new class of proteins that may be termed "cytokine signaling transporters." 相似文献
65.
Timm Konold A Robin Sayers Amanda Sach Gemma E Bone Steven van Winden Gerald AH Wells Marion M Simmons Michael J Stack Angus Wear Steve AC Hawkins 《BMC veterinary research》2010,6(1):53
Background
Various clinical protocols have been developed to aid in the clinical diagnosis of classical bovine spongiform encephalopathy (BSE), which is confirmed by postmortem examinations based on vacuolation and accumulation of disease-associated prion protein (PrPd) in the brain. The present study investigated the occurrence and progression of sixty selected clinical signs and behaviour combinations in 513 experimentally exposed cattle subsequently categorised postmortem as confirmed or unconfirmed BSE cases. Appropriate undosed or saline inoculated controls were examined similarly and the data analysed to explore the possible occurrence of BSE-specific clinical expression in animals unconfirmed by postmortem examinations. 相似文献66.
Michael A. Hardy Justin K. Vreeland William D. Tietje 《Journal of Field Ornithology》2013,84(4):345-354
Conditions in wintering areas can have persistent effects throughout the year for bird populations. Most studies, however, are conducted during the breeding season and the non‐breeding ecology of many species remains poorly understood. We assessed vegetation associations of birds wintering in a diverse, well‐structured oak woodland in coastal‐central California. We calculated density estimates for 20 bird species and examined correlations between bird densities and vegetation characteristics as described by a principal components analysis. Ruby‐crowned Kinglets (Regulus calendula) and Hutton's Vireos (Vireo huttoni) were positively associated with vegetation characteristic of dense, floristically diverse woodland with abundant coast live oak (Quercus agrifolia) cover and a structurally complex understory. Conversely, White‐breasted Nuthatches (Sitta carolinensis) and Western Bluebirds (Sialia mexicana) were negatively correlated with dense woodland and occurred at the highest densities on plots with large widely spaced blue oaks (Q. douglasii) and a sparse understory. Thirteen of the remaining 16 species were more abundant in dense woodland patches, but these relationships were not statistically significant. Our results are in agreement with those of previous studies and suggest that evergreen oak trees and a dense understory provide key resources (e.g., cover and food) for some bird species during the winter. However, areas with large widely spaced deciduous oaks are important habitats for other species. We therefore suggest that dense patches of live oaks and shrubs should be retained, but a mosaic of dense and sparse woodland is necessary to accommodate the entire suite of oak‐woodland birds. 相似文献
67.
RENAN MILAGRES LAGE NOVAES JOSÉ PIRES DE LEMOS FILHO RENATA ACÁCIO RIBEIRO MARIA BERNADETE LOVATO 《Molecular ecology》2010,19(5):985-998
Little is known about past vegetation dynamics in Eastern Tropical South America (ETSA). Here we describe patterns of chloroplast (cp) DNA variation in Plathymenia reticulata, a widespread tree in the ETSA Atlantic Forest and Cerrado biomes, but not found in the xeromorphic Caatinga. Forty one populations, comprising 220 individuals, were analysed by sequencing the trnS‐trnG and trnL‐trnL‐trnF cpDNA regions. Combined, they resulted in 18 geographically structured haplotypes. The central region of the sampling area, comprising Minas Gerais and Goiás Brazilian states, is a centre of genetic diversity and probably the most longstanding area of the distribution range of the species. In contrast, populations from northeastern Brazil and the southern Cerrados showed very low diversity levels, almost exclusively with common haplotypes which are also found in the central region. Coupled with a long‐branched star‐like network, these patterns suggest a recent range expansion of P. reticulata to those regions from central region sources. The recent origin of the species (in the early Pleistocene) or the extinction of some populations due to drier and cooler climate during the last glacial maximum could have been responsible for that phylogeographic pattern. The populations from northeastern Brazil originated from two colonization routes, one eastern (Atlantic) and one western (inland). Due to its high diversity and complex landscape, the central region, especially central‐north Minas Gerais (between 15°–18° S and 42°–46° W), should be given the highest priority for conservation. 相似文献
68.
Background
The fish, Erythrinus erythrinus, shows an interpopulation diversity, with four karyomorphs differing by chromosomal number, chromosomal morphology and heteromorphic sex chromosomes. Karyomorph A has a diploid number of 2n = 54 and does not have differentiated sex chromosomes. Karyomorph D has 2n = 52 chromosomes in females and 2n = 51 in males, and it is most likely derived from karyomorph A by the differentiation of a multiple X1X2Y sex chromosome system. In this study, we analyzed karyomorphs A and D by means of cytogenetic approaches to evaluate their evolutionary relationship. 相似文献69.
Jennie Ursum Wouter H Bos Nancy van Dillen Ben AC Dijkmans Dirkjan van Schaardenburg 《Arthritis research & therapy》2010,12(1):R8
Introduction
To investigate whether baseline levels of anti-citrullinated protein antibody (ACPA) or IgM rheumatoid factor (IgM-RF) and changes in the year thereafter are associated with disease activity, functional and radiographic outcome in early arthritis patients, and provide additional information over baseline autoantibody status. 相似文献70.
Victor X Jin Gregory AC Singer Francisco J Agosto-Pérez Sandya Liyanarachchi Ramana V Davuluri 《BMC bioinformatics》2006,7(1):114-13