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91.
92.
Levels of circulating cell-free nuclear and mitochondrial DNA in benign and malignant ovarian tumors
Zachariah RR Schmid S Buerki N Radpour R Holzgreve W Zhong X 《Obstetrics and gynecology》2008,112(4):843-850
OBJECTIVE: To analyze the levels of circulating cell-free nuclear DNA and circulating cell-free mitochondrial DNA in patients with benign and malignant ovarian tumors using a gold-standard assay and to investigate whether quantitative alterations of the circulating cell-free species have values in the management of the patients. METHODS: One hundred four patients were recruited for this study. We developed a quantitative, multiplex polymerase chain reaction to measure the levels of circulating cell-free nuclear DNA and circulating cell-free mitochondrial DNA in serum and plasma of patients with epithelial ovarian cancer, benign epithelial ovarian tumors, or endometriosis. The levels of the circulating cell-free DNA were compared with those of a healthy, age-matched control group. RESULTS: The patients with epithelial ovarian cancer had significantly higher amounts of circulating cell-free nuclear DNA and circulating cell-free mitochondrial DNA in plasma compared with the healthy control group (mean of nuclear DNA 10,723/2,591 and mean of mitochondrial DNA 4,918,978/2,294,264, P=.009 and 0.022, respectively) and with the other group with benign ovarian diseases (mean of nuclear DNA 10,723/2,965 and mean of mitochondrial DNA 4,918,978/1,597,551, P=.027 and 0.002, respectively). However, no relationship between levels of the circulating cell-free DNA and the pathological parameters as well as CA 125 measurement in patients with epithelial ovarian cancer was found. A significant difference between the epithelial ovarian cancer and endometriosis group was found in circulating cell-free mitochondrial DNA but not in circulating cell-free nuclear DNA (mean of mitochondrial DNA 4,918,978/2,273,988 and mean of nuclear DNA 10,723/3,291, P=.013 and 0.105, respectively). CONCLUSION: Elevated levels of circulating cell-free nuclear DNA and circulating cell-free mitochondrial DNA in epithelial ovarian cancer may have diagnostic value. Our finding suggests that the circulating molecules might be potential biomarkers in the disease. 相似文献
93.
The influence of pregnancy and gender on perivascular innervation of rat posterior cerebral arteries
Aukes AM Bishop N Godfrey J Cipolla MJ 《Reproductive sciences (Thousand Oaks, Calif.)》2008,15(4):411-419
The authors investigated the influence of pregnancy and gender on the density of trigeminal and sympathetic perivascular nerves in posterior cerebral arteries (PCA) and the reactivity to norepinephrine and calcitonin gene-related peptide (CGRP). PCAs were isolated from nonpregnant, late-pregnant, postpartum, and male rats, mounted and pressurized on an arteriograph chamber to obtain concentration-response curves to norepinephrine and CGRP. Arteries were immunostained for CGRP-, tyrosine hydroxylase-, and protein gene product 9.5 (PGP 9.5)-containing perivascular nerves, and nerve density was determined morphologically. Pregnancy had a trophic effect on trigeminal perivascular innervation (P < .01 vs male); however, this was not accompanied by a change in reactivity to CGRP. Sympathetic and PGP 9.5 nerve densities were not altered by pregnancy or gender, and there were no differences in reactivity to norepinephrine. Together, these results suggest that the increase in trigeminal innervation during pregnancy is more related to nociception than in controlling resting cerebral blood flow. 相似文献
94.
Rubio BK Robinson SJ Avalos CE Valeriote FA de Voogd NJ Crews P 《Journal of natural products》2008,71(8):1475-1478
The dramatic biogeographical variations in the secondary metabolites from Psammocinia aff. bulbosa have complicated our efforts to reisolate the two most cytotoxic of its metabolites, (+)-psymberin and (+)-cyclocinamide A. Reported now are the results of a new study that demonstrates our ability to repeatedly isolate these two compounds through targeted collection efforts. Additional study of the new sample of (+)-cyclocinamide A has enabled finalizing its biological activity and absolute stereochemistry as 4S, 7S, 11S, 14S. 相似文献
95.
Androgens and insulin are endocrine key players in the pathophysiology of polycystic ovary syndrome (PCOS), a heterogenic condition of unexplained etiology and a suspected genetic background. Androgens mediate the clinical phenotype of the disease. Therefore,all criteria of the recent PCOS consensus definition are based on their biological effects. Insulin resistance, followed by compensatory hyperinsulinemia, is frequently found in patients with PCOS. Insulin resistance is correlated with a risk of metabolic complications of PCOS, and recent research has focused on possible long-term health consequences of the syndrome. Newest molecular genetic findings at the receptor level of both androgens and insulin support their pivotal role in PCOS. These results could help to better characterize the heterogenic disorder, enabling a refinement of existing individualized therapeutic strategies. 相似文献
96.
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98.
Favre R Duchange N Vayssière C Kohler M Bouffard N Hunsinger MC Kohler A Mager C Neumann M Vayssière C Viville B Hervé C Moutel G 《Prenatal diagnosis》2007,27(3):197-205
OBJECTIVES: To evaluate the level of information and informed consent for maternal serum screening (MSS) for Down syndrome (DS) in the second trimester of pregnancy and analyse the exercise of autonomy towards the test by the women concerned. METHODS: We studied the population of pregnant women attending obstetric consultations in two French hospitals over a 3-month period. The women were assigned to three groups according to MSS results for DS: women at high risk of having a child with DS (group 1), women at low risk (group 2) and women who did not undergo the test (group 3). A questionnaire was completed before the medical consultation, to assess the quality of consent before amniocentesis for the group at high risk and before the second-trimester ultrasound scan for the other two groups. RESULTS: We analysed 305 questionnaires for 89, 137 and 79 women belonging to groups 1, 2 and 3 respectively. In total, 123 women (40.3% [IC 95%, 35-46%]) were considered to be well informed; 33 (10%, [IC 95%, 8-12%]) had a high level of knowledge, but made choices not consistent with their stated attitude, and 149 (49.7% [IC 95%, 45-56%]) were considered uninformed. Logistic regression analysis showed that maternal consent depended on three independent components: The score attributed to the doctor for information about MSS (t = 4.216, p < 0.001).Whether the patient belonged to group 1 (t = -2.631, p < 0.009).Educational level (< high-school diploma, high-school diploma or at least two years of higher education after high school) (t = 2.324, p < 0.02). The rate of consent increased with educational level and was highest for the women in group 1 and for those whose doctor had a high information score. CONCLUSIONS: Our findings clearly show that women are provided with insufficient information concerning MSS screening for DS in the second trimester of pregnancy for real and valid consent to be obtained. 相似文献
99.
Anna Suchankova Margarita Stampelou Klontiana Koutsouki Athanasios Pousias Lakshiv Dhingra Kerry Barkan Nicole Pouli Panagiotis Marakos Roxane Tenta Antonios Kolocouris Nikolaos Lougiakis Graham Ladds 《ACS medicinal chemistry letters》2022,13(6):923
Here we describe the design and synthesis of pyrazolo[3,4-d]pyridazines as adenosine receptor (AR) ligands. We demonstrate that the introduction of a 3-phenyl group, together with a 7-benzylamino and 1-methyl group at the pyrazolopyridazine scaffold, generated the antagonist compound 10b, which displayed 21 nM affinity and a residence time of ∼60 min, for the human A1R, 55 nM affinity and a residence time of ∼73 min, for the human A3R and 1.7 μΜ affinity for the human A2BR while not being toxic. Strikingly, the 2-methyl analog of 10b, 15b, had no significant affinity. Docking calculations and molecular dynamics simulations of the ligands inside the orthosteric binding area suggested that the 2-methyl group in 15b hinders the formation of hydrogen bonding interactions with N6.55 which are considered critical for the stabilization inside the orthosteric binding cavity. We, therefore, demonstrate that 10a is a novel scaffold for the development of high affinity AR ligands. From the mutagenesis experiments the biggest effect was observed for the Y2717.46A mutation which caused an ∼10-fold reduction in the binding affinity of 10b. 相似文献
100.
Frances A. Tylavsky Luhang Han Lauren M. Sims Taylor W. Alex Mason Kecia N. Carroll Nicole R. Bush Kaja Z. LeWinn Melissa M. Melough Terryl J. Hartman Qi Zhao 《Nutrients》2022,14(11)
The objective of this study was to calculate an oxidative balance score (OBS) utilizing diet and lifestyle information collected from 1322 women during the second trimester of pregnancy in the Conditions Affecting Neurocognitive Development and Learning in Early Childhood study. An energy-adjusted OBS was calculated using nutrient information from a Food Frequency Questionnaire (FFQ), lifestyle measures, and plasma folate and vitamin D levels. Using the least absolute shrinkage and selection operator method, 91 food items from the FFQ were selected and they accounted for 82% of the variance in the OBS, with cruciferous vegetables, citrus fruits, fruit juice, and coffee being among the highest anti-oxidant predictors, and red meats and alcohol among the highest pro-oxidant contributors. Urinary F2-isoprostane, an objective indicator of oxidative stress, was lower with increasing OBS quintiles in a stairstep manner (p for trend = 0.0003), suggesting the possible utility of the OBS as an indicator of oxidative stress. The OBS was moderately correlated with the Healthy Eating Index (correlation coefficient = 0.6076), suggesting it provides a distinct measure of a healthy diet. In conclusion, the OBS may serve as a valid reflective indicator of urinary F2-isoprostanes and an epidemiological tool to inform intervention studies, in order to minimize oxidative stress during pregnancy. 相似文献