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101.
Ornella J Rullo Jennifer MP Woo Miriam F Parsa Alice DC Hoftman Paul Maranian David A Elashoff Timothy B Niewold Jennifer M Grossman Bevra H Hahn Maureen McMahon Deborah K McCurdy Betty P Tsao 《Arthritis research & therapy》2013,15(1):R18
Introduction
Osteopontin (OPN) has been implicated as a mediator of Th17 regulation via type I interferon (IFN) receptor signaling and in macrophage activity at sites of tissue repair. This study assessed whether increased circulating plasma OPN (cOPN) precedes development of organ damage in pediatric systemic lupus erythematosus (pSLE) and compared it to circulating plasma neutrophil gelatinase-associated lipocalin (cNGAL), a predictor of increased SLE disease activity.Methods
cOPN and cNGAL were measured in prospectively followed pSLE (n = 42) and adult SLE (aSLE; n = 23) patients and age-matched controls. Time-adjusted cumulative disease activity and disease damage were respectively assessed using adjusted-mean SLE disease activity index (SLEDAI) (AMS) and SLICC/ACR damage index (SDI).Results
Compared to controls, elevated cOPN and cNGAL were observed in pSLE and aSLE. cNGAL preceded worsening SLEDAI by 3-6 months (P = 0.04), but was not associated with increased 6-month AMS. High baseline cOPN, which was associated with high IFNalpha activity and expression of autoantibodies to nucleic acids, positively correlated with 6-month AMS (r = 0.51 and 0.52, P = 0.001 and 0.01 in pSLE and aSLE, respectively) and was associated with SDI increase at 12 months in pSLE (P = 0.001). Risk factors for change in SDI in pSLE were cOPN (OR 7.5, 95% CI [2.9-20], P = 0.03), but not cNGAL, cumulative prednisone, disease duration, immunosuppression use, gender or ancestry using univariate and multivariate logistic regression. The area under the curve (AUC) when generating the receiver-operating characteristic (ROC) of baseline cOPN sensitivity and specificity for the indication of SLE patients with an increase of SDI over a 12 month period is 0.543 (95% CI 0.347-0.738; positive predictive value 95% and negative predictive value 38%).Conclusion
High circulating OPN levels preceded increased cumulative disease activity and organ damage in SLE patients, especially in pSLE, and its value as a predictor of poor outcome should be further validated in large longitudinal cohorts. 相似文献102.
103.
C. E. ALMEIDA E. FOLLY‐RAMOS A. T. PETERSON V. LIMA‐NEIVA M. GUMIEL R. DUARTE M. M. LIMA M. LOCKS M. BELTRÃO J. COSTA 《Medical and veterinary entomology》2009,23(4):410-417
Searches for Chagas disease vectors were performed at the type locality from which Triatoma sherlocki Papa et al. (Hemiptera: Reduviidae: Triatominae) was described in the municipality of Gentio do Ouro, in the state of Bahia, Brazil, and in a small artisan quarry‐mining community ~13 km distant in a remote area of the same municipality. The latter site represents a new locality record for this species. Adults, nymphs and exuviae of T. sherlocki were found in 21% of human dwellings, indicating that the species is in the process of domiciliation. Prevalence of Trypanosoma cruzi infection in collected bugs was 10.8%. Simple predictive approaches based on environmental similarity were used to identify additional sites likely suitable for this species. The approach successfully predicted an additional five sites for the species in surrounding landscapes. Ecological and entomological indicators were combined to discuss whether this scenario likely represents an isolated case or an emerging public health problem. 相似文献
104.
M. A. PETERSON K. J. MONSEN H. PEDERSEN T. MCFARLAND J. BEARDEN 《Biological journal of the Linnean Society. Linnean Society of London》2005,84(2):273-286
The chrysomelid beetles Chrysochus auratus and C. cobaltinus form a narrow hybrid zone in western North America. We used a combination of direct and indirect analyses to examine the fitness of Chrysochus hybrids. For the direct analyses, we compared the mating frequency, longevity, fecundity and fertility of hybrid females and parentals. For the indirect approach, we tested predictions of multilocus genotype frequencies at a focal site in the hybrid zone, based on the frequencies of mating combinations during the previous generation. Hybrid females produced fewer eggs than did parentals and the eggs they produced in the lab failed to hatch, in contrast to those of parental females. In addition, contrary to predictions that 15.8% of the individuals at the focal site would have multilocus genotypes other than those expected of parentals or F1 individuals, we found no such genotypes at this site. This hybrid zone appears to be an example of a classic tension zone, with endogenous selection against hybrid individuals. We discuss the implications of low hybrid fitness for the evolution of premating barriers in this system, and argue that the integration of direct and indirect approaches is a powerful means of assessing the relative fitness of hybrids, particularly for species in which mate choices are easy to observe in the field. © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 84 , 273–286. 相似文献
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J. E. KEISTER E. DI LORENZO C. A. MORGAN V. COMBES W. T. PETERSON 《Global Change Biology》2011,17(7):2498-2511
In the Northern California Current (NCC), zooplankton communities show interannual and multiyear shifts in species dominance that are tracked by survival of salmon populations. These zooplankton community changes correlate with the Pacific Decadal Oscillation (PDO) index: a ‘warm‐water’ copepod species group is more abundant during warm (positive) phases of the PDO and less abundant during cold (negative) phases; the reverse occurs for a ‘cold‐water’ species group. The observed relationship led to the hypothesis that the relative dominance of warm/cold‐water copepods in the NCC is driven by changes in the horizontal advection of surface water over different phases of the PDO. To test this hypothesis, variation in surface water advection to coastal regions of the NCC over the period of 1950–2008 was investigated using a Regional Ocean Modeling System (ROMS) and passive tracer experiments, then was compared with zooplankton collected off Oregon since 1996. Results showed that surface water advection varied with the phase of the PDO; the low‐frequency component of advection anomalies strongly correlated with copepod species composition (R>0.9). During positive phases of the PDO, current anomalies were northward and onshore, resulting in transport of warmer waters and the associated copepods into the region. During negatives phases, increased equatorward current anomalies led to a copepod community that was dominated by cold‐water taxa. Our results support the hypothesis that climate‐driven changes in basin‐scale circulation controls copepod community composition in the NCC, and demonstrate that large‐scale climate forcings downscale to influence local and regional ecosystem structure. 相似文献
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110.
BRET A. COLLIER KYLE B. MELTON JUSTIN Z. DREIBELBIS WILLIAM P. KUVLESKY GLENN A. PROUDFOOT RAY AGUIRRE DAVID G. HEWITT T. W. SCHWERTNER STEPHEN J. DEMASO NOVA J. SILVY MARKUS J. PETERSON 《The Journal of wildlife management》2007,71(6):1793-1799
Abstract: We evaluated brood sex ratio (BSR) variation in Rio Grande wild turkeys (RGWT; Meleagris gallopavo intermedia) in the Edwards Plateau and South Texas Plains of Texas, USA, during 2005-2006. Offspring sex was determined from DNA extracted from tissue biopsies of embryos from unhatched eggs or vascular tissue from eggshells of hatched and depredated eggs. Sex ratio across all eggs was 56.3% male (135/240; X21 = 3.75, P = 0.053). We found that mean population growth rate based on a population simulation with BSR at unity averaged 1.02 (range = 0.924-1.058), whereas it declined to 0.978 (range = 0.816-1.037) using BSR estimates from our study. Although our statistical analyses did not detect BSRs different from unity in BSR, our simulation modeling demonstrated that BSR variation caused biologically significant differences in mean population growth rates. Even though the biological mechanism controlling primary sex ratio remains unknown, our estimates of BSR should allow managers to more reliably predict population dynamics insuring viable RGWT populations across Texas. 相似文献