18 research outputs found

    Novel polythiophene derivatives functionalized withconjugated side-chain pendants comprisingtriphenylamine/carbazole moieties for photovoltaic cellapplications†

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    We synthesized a series of polythiophenes (PTs) featuring 2-ethylhexyl-substituted terthiophene (T) orquaterthiophene (BT) as the conjugated unit in the polymer backbone with pendant conjugated tertbutyl-substituted triphenylamine (tTPA)- or carbazole (tCz)-containing moieties as side chains, namelyPTtTPA, PBTtTPA, PTtCz and PBTtCz. Incorporating T and BT moieties into the polymer backbone andattaching tTPA or tCz units promoted efficient conjugation within the extended conjugated frameworksof the polymers, resulting in lower band-gap energies and red-shifting of the maximal UV-Visabsorption wavelength. The higher electron-donating ability of tTPA resulted in broader absorptionbands and lower band-gap energies of PTtTPA and PBTtTPA as compared with PTtCz and PBTtCz.Incorporation of the T and BT moieties into the polymer backbone enhanced the compatibility of PTand the fullerene derivative by reducing the side-chain density of PT, thus providing sufficient freevolume for efficient incorporation of [6,6]phenyl-C61-butyric acid methyl ester (PC61BM) into thepolymer chains. Polymer solar cells (PSCs) were fabricated by spin-coating a blend of each PT with thefullerene derivative (PC61BM) as a composite film-type photoactive layer; PBTtTPA/PC61BM-based PSCsshowed superior photovoltaic (PV) performance to PTtTPA/PC61BM-based PSCs in terms of conjugationand absorption band broadness. However, PBTtCz/PC61BM-based PSCs showed inferior PV performanceto PTtCz/PC61BM-based PSCs. The lower HOMO level led to a higher open-circuit voltage (Voc; 0.74 V)and larger photo-energy conversion efficiency (h; 2.77%) of PTtCz/PC61BM-based PSCs

    Comparison of Quinn's Advantage fertilization medium and tissue culture medium 199 for in vitro maturation of oocytes

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    AbstractObjectiveThe purpose of the study was to compare the Quinn's Advantage fertilization medium (Q1) and the tissue culture medium 199 (TCM199) for in vitro maturation (IVM) of oocytes and ammonium production during IVM.Materials and methodsThe immature murine oocytes were randomly added into Q1 and TCM199. Ammonium concentrations were measured at the start and after 18 hours of IVM, and the mature oocytes were fertilized and cultured into blastocysts. The blastocysts were then stained for inner cell mass (ICM) and trophectoderm.ResultsThe maturation rate was higher in Q1 than in TCM199 (85.7% vs. 76.6%, p = 0.024). The fertilization and blastocyst rates were slightly higher in Q1, but not significant. Differential staining of the blastocysts showed slightly higher ICM ratio in the blastocysts derived from Q1. Mean ammonium concentrations in Q1 and TCM199 at Time 0 were 184.9 and 339.2 μg/dL, respectively (p = 0.05), and after 18 hours of IVM were 268.7 and 443.6 μg/dL, respectively (p = 0.045). Addition of ammonium chloride into Q1 adversely affects IVM.ConclusionQ1 is superior to TCM199 in terms of oocyte maturation, which may be due to lower ammonium concentration

    Feasibility of corifollitropin alfa/GnRH antagonist protocol combined with GnRH agonist triggering and freeze-all strategy in polycystic ovary syndrome patients

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    Background/Purpose: The long-acting corifollitropin alfa is comparable to FSH in terms of pregnancy outcomes in normal responders and poor responders. Corifollitropin alfa has never been studied in polycystic ovary syndrome (PCOS) patients because of concerns of excessive ovarian stimulation and ovarian hyperstimulation syndrome (OHSS). The purpose of the study was to evaluate if corifollitropin alfa can be used in PCOS patients. Methods: Forty PCOS patients who were going to undergo in vitro fertilization were enrolled in this study. A single injection of corifollitropin alfa was administered on cycle day 2 or day 3. From stimulation day 8 onwards, daily FSH was administered until the day of final oocyte maturation. Cetrorelix was administered from stimulation day 5 to prevent premature LH surge. Final oocyte maturation was triggered by: acetate. All embryos were cryopreserved and replaced in subsequent cycles. Results: All 40 patients were subjected to oocyte retrieval, and none developed moderate or severe ovarian hyperstimulation syndrome (0%, 95% CI 0–0.088). For each patient, an average of 23.4 (±7.4; 95% CI 21.0–25.7) oocytes were retrieved and a mean of 11.7 (±6.4; 95% CI 9.6–13.8) embryos were frozen. Mean serum estradiol level on the day of GnRHa triggering was 7829.9 pg/ml (±3297; 95% CI 6775–8885). The cumulated ongoing pregnancy rate after 3 frozen-thawed embryo transfers was 75.0% (95% CI 61.6%–88.4%). Conclusion: The results suggest that corifollitropin alfa/GnRH antagonist protocol can be used in PCOS patients, in combination with GnRHa triggering and embryo cryopreservation. Keywords: Corifollitropin alfa, Cryopreservation, GnRH agonist, Polycystic ovary syndrom

    Ovatodiolide Inhibits Breast Cancer Stem/Progenitor Cells through SMURF2-Mediated Downregulation of Hsp27

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    Cancer stem/progenitor cells (CSCs) are a subpopulation of cancer cells involved in tumor initiation, resistance to therapy and metastasis. Targeting CSCs has been considered as the key for successful cancer therapy. Ovatodiolide (Ova) is a macrocyclic diterpenoid compound isolated from Anisomeles indica (L.) Kuntze with anti-cancer activity. Here we used two human breast cancer cell lines (AS-B145 and BT-474) to examine the effect of Ova on breast CSCs. We first discovered that Ova displayed an anti-proliferation activity in these two breast cancer cells. Ova also inhibited the self-renewal capability of breast CSCs (BCSCs) which was determined by mammosphere assay. Ova dose-dependently downregulated the expression of stemness genes, octamer-binding transcription factor 4 (Oct4) and Nanog, as well as heat shock protein 27 (Hsp27), but upregulated SMAD ubiquitin regulatory factor 2 (SMURF2) in mammosphere cells derived from AS-B145 or BT-474. Overexpression of Hsp27 or knockdown of SMURF2 in AS-B145 cells diminished the therapeutic effect of ovatodiolide in the suppression of mammosphere formation. In summary, our data reveal that Ova displays an anti-CSC activity through SMURF2-mediated downregulation of Hsp27. Ova could be further developed as an anti-CSC agent in the treatment of breast cancer
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