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71.
Estrogenic and antiproliferative activities on MCF-7 human breast cancer cells by flavonoids 总被引:5,自引:0,他引:5
The interaction between the estrogen receptor and a variety of flavonoids was studied in the presence or absence of estradiol using a stably-transfected human breast cancer cell line (MVLN). On the other hand, flavonoids were evaluated for their effects on proliferation in estrogen-dependent (MCF-7) and independent (MDA-MB231) human breast cancer cells. We established a relationship structure-activity and determined regions and/or substituents essential for estrogenic or antiestrogenic activities. In contrast, we did not find the same relationship for cell proliferation. Among all flavonoids used, only 7-methoxyflavanone and 7,8-dihydroxyflavone at high concentrations (50 μM) possess antiestrogenic and antiproliferative activities. These results suggest that two hydroxyls (in positions 7 and 8) or 7-methoxy substituents are essential for the antiestrogenic activity of flavonoids. However, it seems that flavonoids at high concentrations exert their antiproliferative activity through other estrogen receptor-independent mechanisms. 相似文献
72.
Victor Palomar-Asenjo Ma Soledad Boleas-Aguirre Noelia Sánchez-Ferrándiz Nicolas Perez Fernandez 《Otology & neurotology》2006,27(7):945-950
OBJECTIVES: To determine whether an association exists between the parameters of the caloric and rotatory chair tests in patients with unilateral Ménière's disease. METHODS: Patients with unilateral Ménière's disease (n = 100) were subjected to the caloric and the rotatory chair test (sinusoidal harmonic acceleration and impulsive tests) on the same day. Canal paresis and directional preponderance were assessed in the caloric test, and different variables were measured in the rotatory chair test based on the existence of abnormal parameters in the vestibulo-ocular reflex at two or three consecutive frequencies of those tested and on the time constant of the vestibulo-ocular reflex. STUDY DESIGN AND SETTING: A prospective study was conducted at a University hospital. RESULTS: An abnormal result in the caloric test was obtained from 73% of the patients. In the rotatory chair test, the most frequent abnormal findings involved increases in the normal phase lead at 2 consecutive frequencies tested (23%). There was a stronger association between an abnormal result in phase, gain, and/or symmetry at three adjacent frequencies and a pathological result in the caloric test. CONCLUSION: Very few of the criteria used to define the caloric and rotatory chair tests seem to be associated. This confirms previous knowledge that both tests examine vestibulo-ocular reflex by different ways. Only when vestibular dysfunction is severe enough (manifested by the finding of an abnormal result in at least three consecutive frequencies in the rotatory chair test), the caloric test is also found to be abnormal. 相似文献
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74.
Renaud Sabatier Ccile Vicier Sverine Garnier Arnaud Guille Nadine Carbuccia Nicolas Isambert Florence Dalenc Marie Robert Christelle Levy Jihane Pakradouni Jos Adelaïde Max Chaffanet Patrick Sfumato Emilie Mamessier Franois Bertucci Anthony Goncalves 《Molecular oncology》2022,16(10):2057
The phosphatidylinositol‐3‐kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway is frequently activated in HER2‐negative breast cancer and may play a role in taxane resistance. The phase IB/II TAKTIC trial () has shown that combining a dual AKT and p70 ribosomal protein S6 kinase (p70S6K) inhibitor (LY2780301) taken orally with weekly paclitaxel in HER2‐negative advanced breast cancer is feasible, with preliminary evidence of efficacy. We wanted to explore whether circulating tumor DNA (ctDNA) may be a surrogate marker of treatment efficacy in this setting. Serial plasma samples were collected and cell‐free DNA was sequenced using low‐coverage whole‐genome sequencing, and analysis was completed with droplet digital polymerase chain reaction (PCR) for some patients with driver mutations. Baseline tumor fraction (TF) and TF after 7 weeks on treatment were compared to progression‐free survival (PFS) and the overall response rate. We also explored circulating copy number alterations associated with treatment failure. Of the 51 patients enrolled in the TAKTIC trial, at least one plasma sample was available for 44 cases (96 timepoints). All patients with tumor TP53, PI3KCA, or AKT1 mutations harbored at least one of these alterations in plasma. TF at inclusion was correlated with PFS (6m‐PFS was 92% for ctDNAneg patients vs 68% for ctDNApos cases; hazard ratio [HR] = 3.45, 95% confidence interval [CI] [1.34–8.90], P = 0.007). ctDNA status at week 7 was not correlated with prognosis. Even though most circulating copy number alterations were conserved at disease progression, some genomic regions of interest were altered in post‐progression samples. In conclusion, ctDNA detection at baseline was associated with shorter PFS in patients included in the TAKTIC trial. Plasma‐based copy number analysis may help to identify alterations involved in resistance to treatment. NCT01980277相似文献
75.
Ysmael Verde-Gmez Elizabeth Montiel-Macías Ana María Valenzuela-Muiz Ivonne Alonso-Lemus Mario Miki-Yoshida Karim Zaghib Nicolas Brodusch Raynald Gauvin 《Materials》2022,15(10)
In the past few decades, nanostructured carbons (NCs) have been investigated for their interesting properties, which are attractive for a wide range of applications in electronic devices, energy systems, sensors, and support materials. One approach to improving the properties of NCs is to dope them with various heteroatoms. This work describes the synthesis and study of sulfur-added carbon nanohorns (S-CNH). Synthesis of S-CNH was carried out by modified chemical vapor deposition (m-CVD) using toluene and thiophene as carbon and sulfur sources, respectively. Some parameters such as the temperature of synthesis and carrier gas flow rates were modified to determine their effect on the properties of S-CNH. High-resolution scanning and transmission electron microscopy analysis showed the presence of hollow horn-type carbon nanostructures with lengths between 1 to 3 µm and, diameters that are in the range of 50 to 200 nm. Two types of carbon layers were observed, with rough outer layers and smooth inner layers. The surface textural properties are attributed to the defects induced by the sulfur intercalated into the lattice or bonded with the carbon. The XRD patterns and X-ray microanalysis studies show that iron serves as the seed for carbon nanohorn growth and iron sulfide is formed during synthesis. 相似文献
76.
The growing demand for wood-based panels for buildings and furniture and the increasing worldwide concern for reducing the pressure on forest resources require alternatives to wood raw materials. The agricultural industry not only can provide raw materials from non-wood plants but also numerous residues and side streams. This review supplies an overview of the availability, chemical composition, and fiber characteristics of non-wood lignocellulosic materials and agricultural residues, i.e., grow care residues, harvest residues, and process residues, and their relevance for use in wood panel manufacturing. During the crop harvest, there are millions of tons of residues in the form of stalks, among other things. Usually, these are only available seasonally without using storage capacity. Process residues, on the other hand, can be taken from ongoing production and processed further. Fiber characteristics and chemical composition affect the panel properties. Alternatives to wood with long fibers and high cellulose content offer sufficient mechanical strength in different panel types. In general, the addition of wood substitutes up to approximately 30% provides panels with the required strength properties. However, other parameters must be considered, such as pressing temperature, adhesive type, press levels, and pretreatments of the raw material. The search for new raw materials for wood panels should focus on availability throughout the year, the corresponding chemical requirements and market competition. Panel type and production process can be adapted to different raw materials to fit niche products. 相似文献
77.
Michael D. Dub Christopher A. Rothfusz Ahmed K. Emara Matthew Hadad Peter Surace Viktor E. Krebs Robert M. Molloy Nicolas S. Piuzzi 《Current reviews in musculoskeletal medicine》2022,15(4):311
Purpose of Review8.5 to 50% of total joint arthroplasty (TJA) patients are reported to have preoperative malnutrition. The narrative review identifies the relationship between preoperative malnutrition for TJA patients and postoperative outcomes as well as the use of perioperative nutritional intervention to improve postoperative complications.Recent FindingsBiochemical/laboratory, anthropometric, and clinical measures have been widely used to identify preoperative nutritional deficiency. Specifically, serum albumin is the most prevalent used marker in TJA because it has been proven to be correlated with protein-energy malnutrition due to the surgical stress response. However, there remains a sustained incidence of preoperative malnutrition in total knee arthroplasty (TKA) and total hip arthroplasty (THA) patients due to a lack of agreement among the available nutritional screening tools and utilization of isolated laboratory, anthropometric, and clinical variables. Previous investigations have also suggested preoperative malnutrition to be a prognostic indicator of complications in general, cardiac, vascular, and orthopaedic surgery specialties.SummarySerum albumin, prealbumin, transferrin, and total lymphocyte count (TLC) can be used to identify at-risk patients. It is important to employ these markers in the preoperative setting because malnourished TKA and THA patients have shown to have worse postoperative outcomes including prolonged length, increased reoperation rates, increased infection rates, and increased mortality rates. Although benefits from high-protein and high-anti-inflammatory diets have been exhibited, additional research is needed to confirm the use of perioperative nutritional intervention as an appropriate treatment for preoperative TJA patients. 相似文献
78.
vom Saal FS Akingbemi BT Belcher SM Birnbaum LS Crain DA Eriksen M Farabollini F Guillette LJ Hauser R Heindel JJ Ho SM Hunt PA Iguchi T Jobling S Kanno J Keri RA Knudsen KE Laufer H LeBlanc GA Marcus M McLachlan JA Myers JP Nadal A Newbold RR Olea N Prins GS Richter CA Rubin BS Sonnenschein C Soto AM Talsness CE Vandenbergh JG Vandenberg LN Walser-Kuntz DR Watson CS Welshons WV Wetherill Y Zoeller RT 《Reproductive toxicology (Elmsford, N.Y.)》2007,24(2):131-138
79.
80.