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81.
Lian Shan Y. Ann Chen Lorelei Davis Gang Han Weiwei Zhu Ashley D. Molina Hector Arango James P. LaPolla Mitchell S. Hoffman Thomas Sellers Tyler Kirby Santo V. Nicosia Rebecca Sutphen 《PloS one》2012,7(10)
Background
More than two-thirds of women who undergo surgery for suspected ovarian neoplasm do not have cancer. Our previous results suggest phospholipids as potential biomarkers of ovarian cancer. In this study, we measured the serum levels of multiple phospholipids among women undergoing surgery for suspected ovarian cancer to identify biomarkers that better predict whether an ovarian mass is malignant.Methodology/Principal Findings
We obtained serum samples preoperatively from women with suspected ovarian cancer enrolled through a prospective, population-based rapid ascertainment system. Samples were analyzed from all women in whom a diagnosis of epithelial ovarian cancer (EOC) was confirmed and from benign disease cases randomly selected from the remaining (non-EOC) samples. We measured biologically relevant phospholipids using liquid chromatography/electrospray ionization mass spectrometry. We applied a powerful statistical and machine learning approach, Hybrid huberized support vector machine (HH-SVM) to prioritize phospholipids to enter the biomarker models, and used cross-validation to obtain conservative estimates of classification error rates.Results
The HH-SVM model using the measurements of specific combinations of phospholipids supplements clinical CA125 measurement and improves diagnostic accuracy. Specifically, the measurement of phospholipids improved sensitivity (identification of cases with preoperative CA125 levels below 35) among two types of cases in which CA125 performance is historically poor - early stage cases and those of mucinous histology. Measurement of phospholipids improved the identification of early stage cases from 65% (based on CA125) to 82%, and mucinous cases from 44% to 88%.Conclusions/Significance
Levels of specific serum phospholipids differ between women with ovarian cancer and those with benign conditions. If validated by independent studies in the future, these biomarkers may serve as an adjunct at the time of clinical presentation, to distinguish between women with ovarian cancer and those with benign conditions with shared symptoms and features. 相似文献82.
Yu W Hegarty JP Berg A Chen X West G Kelly AA Wang Y Poritz LS Koltun WA Lin Z 《PloS one》2011,6(5):e20454
BACKGROUND: NKX2-3 is associated with inflammatory bowel disease (IBD). NKX2-3 is expressed in microvascular endothelial cells and the muscularis mucosa of the gastrointestinal tract. Human intestinal microvascular endothelial cells (HIMECs) are actively involved in the pathogenesis of IBD and IBD-associated microvascular dysfunction. To understand the cellular function of NKX2-3 and its potential role underlying IBD pathogenesis, we investigated the genes regulated by NKX2-3 in HIMEC using cDNA microarray. METHODOLOGY/PRINCIPAL FINDINGS: NKX2-3 expression was suppressed by shRNA in two HIMEC lines and gene expression was profiled by cDNA microarray. Pathway Analysis was used to identify gene networks according to biological functions and associated pathways. Validation of microarray and genes expression in intestinal tissues was assessed by RT-PCR. NKX2-3 regulated genes are involved in immune and inflammatory response, cell proliferation and growth, metabolic process, and angiogenesis. Several inflammation and angiogenesis related signaling pathways that play important roles in IBD were regulated by NKX2-3, including endothelin-1 and VEGF-PI3K/AKT-eNOS. Expression levels of NKX2-3, VEGFA, PI3K, AKT, and eNOS are increased in intestinal tissues from IBD patients and expression levels of EDN1 are decreased in intestinal tissues from IBD patients. These results demonstrated the important roles of NKX2-3, VEGF, PI3K, AKT, eNOS, and EDN1 in IBD pathogenesis. Correlation analysis showed a positive correlation between mRNA expression of NKX2-3 and VEGFA and a negative correlation between mRNA expression of NKX2-3 and EDN1 in intestinal tissues from IBD patients. CONCLUSION/RELEVANCE: NKX2-3 may play an important role in IBD pathogenesis by regulating endothelin-1 and VEGF signaling in HIMECs. 相似文献
83.
Martin D. Jacobson Eric T. Tsakiris Ashley M. Long William E. Jensen 《Journal of Field Ornithology》2011,82(2):184-192
ABSTRACT Methods for monitoring bird nests might influence rates of nest predation, but the effects of various methods (e.g., visual markers and observer visitation rates) are often separately investigated among disparate avian taxa and geographic regions. Few investigators have explored the potential effects observers might have on nest success of grassland birds, despite concerns regarding population declines of these species in North America. We examined the possible effects of three monitoring techniques on daily nest survival of Lark Sparrows (Chondestes grammacus): (1) presence or absence of visible markers near nests, (2) observer visitation frequency, and (3) presence or absence of data loggers in nests. We monitored 113 Lark Sparrow nests during the 2009 breeding season. Of these nests, 88.5% failed due to predation, abandonment, weather, or unknown causes, yielding an overall nest success estimate of 9.8% based on daily survival estimation. Main effects of each monitoring technique appeared in top (ΔAICc <2) logistic exposure models. However, 95% confidence intervals around parameter estimates for each technique included zero, indicating no significant effects on daily nest survival. Our results suggest that the nest‐monitoring techniques we used had no effect on Lark Sparrow nest success and, if true, nest survival of other songbirds in arid grasslands of the Great Plains may also be unaffected by cautious nest monitoring. However, we cannot rule out the possibility that any effects of the various techniques in our study were masked by locally intense nest predation. Therefore, additional study is needed to determine if there may be observable variation in nest survival among various nest‐monitoring treatments in other areas of the southern Great Plains where nest predation is less frequent. 相似文献
84.
Ling Zhao L. Dillon Birdwell Ashley Wu Ruth Elliott Kristine M. Rose Judith M. Phillips Yize Li Judith Grinspan Robert H. Silverman Susan R. Weiss 《Journal of virology》2013,87(15):8408-8418
Previous studies have demonstrated that the murine coronavirus mouse hepatitis virus (MHV) nonstructural protein 2 (ns2) is a 2′,5′-phosphodiesterase that inhibits activation of the interferon-induced oligoadenylate synthetase (OAS)-RNase L pathway. Enzymatically active ns2 is required for efficient MHV replication in macrophages, as well as for the induction of hepatitis in C57BL/6 mice. In contrast, following intranasal or intracranial inoculation, efficient replication of MHV in the brain is not dependent on an enzymatically active ns2. The replication of wild-type MHV strain A59 (A59) and a mutant with an inactive phosphodiesterase (ns2-H126R) was assessed in primary hepatocytes and primary central nervous system (CNS) cell types—neurons, astrocytes, and oligodendrocytes. A59 and ns2-H126R replicated with similar kinetics in all cell types tested, except macrophages and microglia. RNase L activity, as assessed by rRNA cleavage, was induced by ns2-H126R, but not by A59, and only in macrophages and microglia. Activation of RNase L correlated with the induction of type I interferon and the consequent high levels of OAS mRNA induced in these cell types. Pretreatment of nonmyeloid cells with interferon restricted A59 and ns2-H126R to the same extent and failed to activate RNase L following infection, despite induction of OAS expression. However, rRNA degradation was induced by treatment of astrocytes or oligodendrocytes with poly(I·C). Thus, RNase L activation during MHV infection is cell type specific and correlates with relatively high levels of expression of OAS genes, which are necessary but not sufficient for induction of an effective RNase L antiviral response. 相似文献
85.
Comparative phylogeography of unglaciated eastern North America 总被引:1,自引:0,他引:1
Regional phylogeographical studies involving co-distributed animal and plant species have been conducted for several areas, most notably for Europe and the Pacific Northwest of North America. Until recently, phylogeographical studies in unglaciated eastern North America have been largely limited to animals. As more studies emerge for diverse lineages (including plants), it seems timely to assess the phylogeography across this region: (i) comparing and contrasting the patterns seen in plants and animals; (ii) assessing the extent of pseudocongruence; and (iii) discussing the potential applications of regional phylogeography to issues in ecology, such as response to climatic change. Unglaciated eastern North America is a large, geologically and topographically complex area with the species examined having diverse distributions. Nonetheless, some recurrent patterns emerge: (i) maritime - Atlantic vs. Gulf Coast; (ii) Apalachicola River discontinuity; (iii) Tombigbee River discontinuity; (iv) the Appalachian Mountain discontinuity; (v) the Mississippi River discontinuity; and (vi) the Apalachicola River and Mississippi River discontinuities. Although initially documented in animals, most of these patterns are also apparent in plants, providing support for phylogeographical generalizations. These patterns may generally be attributable to isolation and differentiation during Pleistocene glaciation, but in some cases may be older (Pliocene). Molecular studies sometimes agree with longstanding hypotheses of glacial refugia, but also suggest additional possible refugia, such as the southern Appalachian Mountains and areas close to the Laurentide Ice Sheet. Many species exhibit distinct patterns that reflect the unique, rather than the shared, aspects of species' phylogeographical histories. Furthermore, similar modern phylogeographical patterns can result from different underlying causal factors operating at different times (i.e. pseudocongruence). One underemphasized component of pseudocongruence may result from the efforts of researchers to categorize patterns visually - similar patterns may, in fact, not fully coincide, and inferring agreement may obscure the actual patterns and lead to erroneous conclusions. Our modelling analyses indicate no clear spatial patterning and support the hypothesis that phylogeographical structure in diverse temperate taxa is complex and was not shaped by just a few barriers. 相似文献
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88.
Ashley MV Caballero IC Chaovalitwongse W Dasgupta B Govindan P Sheikh SI Berger-Wolf TY 《Molecular ecology resources》2009,9(4):1127-1131
A software suite KINALYZER reconstructs full-sibling groups without parental information using data from codominant marker loci such as microsatellites. KINALYZER utilizes a new algorithm for sibling reconstruction in diploid organisms based on combinatorial optimization. KINALYZER makes use of a Minimum 2-Allele Set Cover approach based on Mendelian inheritance rules and finds the smallest number of sibling groups that contain all the individuals in the sample. Also available is a 'Greedy Consensus' approach that reconstructs sibgroups using subsets of loci and finds the consensus of the partial solutions. Unlike likelihood methods for sibling reconstruction, KINALYZER does not require information about population allele frequencies and it makes no assumptions regarding the mating system of the species. KINALYZER is freely available as a web-based service. 相似文献
89.
CT Banek AJ Bauer A Gingery JS Gilbert 《American journal of physiology. Regulatory, integrative and comparative physiology》2012,303(6):R658-R664
Increased uterine artery resistance and angiogenic imbalance characterized by increased soluble fms-like tyrosine kinase-1 (sFlt-1) and decreased free vascular endothelial growth factor (VEGF) are often associated with placental insufficiency and preeclampsia but not synonymous with hypertension. We hypothesized chronic reductions in utero-placental perfusion (RUPP) for 5 days (d) during either mid- (d12-d17) or late (d14-d19) gestation would have disparate effects on plasma sFlt-1 and VEGF levels and blood pressure. Five days of chronic RUPP was achieved by placement of silver clips on the abdominal aorta and ovarian arteries on either gestational d12 or d14. Arterial pressure was increased (P < 0.05) in RUPP vs. normal pregnant (NP) in both d17 (10%) and d19 (25%) groups, respectively. Circulating free VEGF was decreased (P < 0.05) and sFlt-1:VEGF ratio increased (P < 0.05) after 5 days of RUPP ending on d19 but not d17 compared with NP controls. Angiogenic imbalance, measured by an endothelial tube formation assay, was present in the d19 RUPP but not the d17 RUPP compared with age-matched NP rats. Five days of RUPP from days 14 to 19 decreased fetal and placental weights 10% (P < 0.01) compared with d19 NP controls. After 5 days of RUPP, from days 12 to 17 of pregnancy, fetal weights were 21% lighter (P < 0.01) compared with d17 NP controls, but placental weight was unchanged. These findings suggest that the timing during which placental insufficiency occurs may play an important role in determining the extent of alterations in angiogenic balance, fetal growth restriction, and the severity of placental ischemia-induced hypertension. 相似文献
90.
In vivo baseline measurements of hip joint range of motion in suspensory and nonsuspensory anthropoids 下载免费PDF全文
Ashley S. Hammond 《American journal of physical anthropology》2014,153(3):417-434
Hominoids and atelines are known to use suspensory behaviors and are assumed to possess greater hip joint mobility than nonsuspensory monkeys, particularly for range of abduction. This assumption has greatly influenced how extant and fossil primate hip joint morphology has been interpreted, despite the fact that there are no data available on hip mobility in hominoids or Ateles. This study uses in vivo measurements to test the hypothesis that suspensory anthropoids have significantly greater ranges of hip joint mobility than nonsuspensory anthropoids. Passive hip joint mobility was measured on a large sample of anesthetized captive anthropoids (nonhuman hominids = 43, hylobatids = 6, cercopithecids = 43, Ateles = 6, and Cebus = 6). Angular and linear data were collected using goniometers and tape measures. Range of motion (ROM) data were analyzed for significant differences by locomotor group using ANOVA and phylogenetic regression. The data demonstrate that suspensory anthropoids are capable of significantly greater hip abduction and external rotation. Degree of flexion and internal rotation were not larger in the suspensory primates, indicating that suspension is not associated with a global increase in hip mobility. Future work should consider the role of external rotation in abduction ability, how the physical position of the distal limb segments are influenced by differences in ROM proximally, as well as focus on bony and soft tissue differences that enable or restrict abduction and external rotation at the anthropoid hip joint. Am J Phys Anthropol 153:417–434, 2014. © 2013 Wiley Periodicals, Inc. 相似文献