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111.
Steroidogenic enzyme and key decidualization marker dysregulation in endometrial stromal cells from women with versus without endometriosis 总被引:2,自引:0,他引:2
Identification of mechanisms underlying endometriosis pathogenesis will facilitate understanding and treatment of infertility and pain associated with this disorder. Herein, we investigated the expression of steroidogenic pathway enzymes and key decidualization biomarkers in endometrial tissue and in eutopic endometrial stromal fibroblasts (hESFs) from women with vs. those without endometriosis, and subsequently treated in vitro with 8-bromo-cAMP (8-Br-cAMP) or progesterone (P4). Real-time quantitative PCR, immunohistochemistry, ELISA, and radiometric aromatase activity assay were used. The results demonstrate significantly increased (14.5-fold; P=0.037) expression of aromatase in eutopic endometrium of women with disease. In 8-Br-cAMP-treated hESF from eutopic endometrium of women with endometriosis, the balance in estradiol (E2) and P4 biosynthetic and metabolizing enzymes is disturbed (decreased HSD3B1 and HSD17B2, and increased HSD17B1 and aromatase), with the equilibrium being shifted towards an E2-enriched milieu. However, hESF from the same group of women treated with P4 did not demonstrate such responsiveness. Lower expression of IGFBP1 and prolactin mRNA and protein was observed in hESF from women with vs. those without endometriosis in response to 8-Br-cAMP, but not P4, suggesting a blunted response of these decidual biomarkers to activation of the PKA pathway in eutopic endometrium in women with disease. The dichotomy of 8-Br-cAMP regulation of select steroidogenic enzymes leading to an enriched E2 milieu within the endometrium and a blunted response of decidual biomarkers to this decidualizing agent of hESF from women with endometriosis suggests resistance to full decidualization of the stromal fibroblasts and mechanisms underlying implantation failure and the pathophysiology of this disorder. 相似文献
112.
G. E. Maes B. van Vo A. J. Crivelli F. A. M. Volckaert 《Journal of fish biology》2009,74(9):2047-2068
The fine scale morphological and genetic dynamics of successive waves of Anguilla anguilla glass eel recruitment was studied over a 2 year period at a southern European Mediterranean location (Camargue, France) with continuous recruitment. Using morphometric [total length (LT), mass (M), condition (K) and pigmentation stage] as well as genetic (allozyme) markers, the aim was to test for the existence of temporally separated spawning groups and explore the relation between genetic variability and morphological heterogeneity of recruits. The results showed that LT, M and K varied over time, being highest from the end of summer to winter (peaking in December) and lowest in spring (lowest in April). The pigmentation stages within monthly samples were highly diverse with a heterogeneous seasonal pattern. Allozyme data showed high genetic variability values within samples, but low genetic differentiation among samples (FST = 0·003, P < 0·05). Pairwise comparisons between samples indicated a positive correlation between genetic differentiation and difference in recruitment time (days), with a marked increase in genetic differentiation around 250 days between monthly recruitment samples. Furthermore, genetic diversity increased with the number of pigmentation stages per sample and was negatively correlated with the North Atlantic Oscillation (NAO) index during the putative year of trans‐oceanic migration. No correlation, however, was found between the level of multilocus heterozygosity (MLH) and growth variables. A situation of genetic patchiness with fluctuating parental contribution can thus best explain the patterns observed, although the existence of two separate spawning periods cannot be excluded. More discriminatory and sensitive genetic markers, such as (neutral and adaptive) microsatellites, could probably provide additional insights into the most probable hypothesis explaining the population structure and recruitment heterogeneity of A. anguilla. 相似文献
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115.
Maria G. Guzman Thomas Jaenisch Roger Gaczkowski Vo Thi Ty Hang Shamala Devi Sekaran Axel Kroeger Susana Vazquez Didye Ruiz Eric Martinez Juan C. Mercado Angel Balmaseda Eva Harris Efren Dimano Prisca Susan A. Leano Sutee Yoksan Elci Villegas Herminia Benduzu Iris Villalobos Jeremy Farrar Cameron P. Simmons 《PLoS neglected tropical diseases》2010,4(8)
Background
Early diagnosis of dengue can assist patient triage and management and prevent unnecessary treatments and interventions. Commercially available assays that detect the dengue virus protein NS1 in the plasma/serum of patients offers the possibility of early and rapid diagnosis.Methodology/Principal Findings
The sensitivity and specificity of the Pan-E Dengue Early ELISA and the Platelia™ Dengue NS1 Ag assays were compared against a reference diagnosis in 1385 patients in 6 countries in Asia and the Americas. Platelia was more sensitive (66%) than Pan-E (52%) in confirmed dengue cases. Sensitivity varied by geographic region, with both assays generally being more sensitive in patients from SE Asia than the Americas. Both kits were more sensitive for specimens collected within the first few days of illness onset relative to later time points. Pan-E and Platelia were both 100% specific in febrile patients without evidence of acute dengue. In patients with other confirmed diagnoses and healthy blood donors, Platelia was more specific (100%) than Pan-E (90%). For Platelia, when either the NS1 test or the IgM test on the acute sample was positive, the sensitivity versus the reference result was 82% in samples collected in the first four days of fever. NS1 sensitivity was not associated to disease severity (DF or DHF) in the Platelia test, whereas a trend for higher sensitivity in DHF cases was seen in the Pan-E test (however combined with lower overall sensitivity).Conclusions/Significance
Collectively, this multi-country study suggests that the best performing NS1 assay (Platelia) had moderate sensitivity (median 64%, range 34–76%) and high specificity (100%) for the diagnosis of dengue. The poor sensitivity of the evaluated assays in some geographical regions suggests further assessments are needed. The combination of NS1 and IgM detection in samples collected in the first few days of fever increased the overall dengue diagnostic sensitivity. 相似文献116.
117.
Kenyon M Roos C Binh VT Chivers D 《Folia primatologica; international journal of primatology》2011,82(3):154-164
We observed 18 groups of golden-cheeked gibbons (Nomascus gabriellae) in the secondary lowland forest in Cat Tien National Park from January 2004 to December 2005 to obtain information about the social organization of this little-studied species, in an area where the population is recovering through increased protection and forest regeneration. DNA from faecal samples of 10 infants and juveniles identified 1 case of extrapair paternity. DNA from faecal samples of 18 adults from three communities revealed the majority of adults sampled of both sexes to be related to adults in neighbouring territories. Overall, the indications are that in this empty habitat, gibbons appear to be able to establish territories adjacent to those of their kin. 相似文献
118.
D. A. Pavlov N. G. Emel’yanova Luong Thi Bich Thuan Vo Thi Ha 《Journal of Ichthyology》2011,51(8):604-617
Features of reproductive biology and the stages of early ontogeny are described in the mass tropical species manybar goatfish
Parupeneus multifasciatus. In general, in the catches represented by mainly sexually mature fishes, females prevail but males prevail in the largest
size classes. The females reach their first sexual maturity by approximately 110 mm fork length, and they are characterized
by continuous oogenesis and egg deposition in batches. The fish spawn over the entire year with a trend to lower values of
the gonadosomatic index (GSI) of the females from June to October. The features of early ontogeny are compared in manybar
goatfish and red mullet Mullus barbatus ponticus from the Black Sea. 相似文献
119.
Sokolova TV Rychkova MI Voĭnova IV Avrova NF 《Zhurnal evoliutsionno? biokhimii i fiziologii》2011,47(5):375-382
At the short-term incubation (0.5 and 1.5 h) of cells of the PC12 neuronal line with alpha-tocopherol, its protective effect against the cytotoxic hydrogen peroxide action was increased with rise of its concentration in samples; the protection was practically absent at action of nanomolar antioxidant concentrations, but was well expressed at its micromolar concentrations. These data agree with the concept that alpha-tocopherol increases the cell living activity by reacting directly with free radicals, which leads to formation of the less reactive compounds deprived of non-paired electron. The evidence is obtained that at the long-term action on PC12 cells, alpha-tocopherol not only in micro-, but also in nanomolar concentrations increases statistically significantly the cell living activity under conditions of oxidative stress. As follows from the obtained data, an important role in realization of the alpha-tocopherol protective effect at the long-term incubation with it seems to be played by modulation by this antioxidant of activity of protein kinase activated by extracellular signaling, phosphatidylinosite 3-kinase, and protein kinase C. 相似文献
120.