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1.
Angew Chem Int Ed Engl ; 61(14): e202200341, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35119187

RESUMO

Pyracylene is a unique cyclopenta-fused polycyclic aromatic hydrocarbon (CP-PAH) that exhibits dual aromatic characteristics. Herein we report the synthesis of doubly N-doped benzannulated pyracylenes, namely dibenzodiazapyracylenes, by oxidative N-N linking reaction of [2.2](2,5)pyrrolophane-type precursors. Dibenzodiazapyracylenes displayed well-ordered π-stacked molecular packing in the solid state, which were feasible for effective hole-transporting along the stacking direction. High carrier mobility was estimated by microwave conductivity measurements as compared to dibenzoullazine. The high HOMO level of dibenzodiazapyracylene was verified by electrochemistry and its persistent radical cation species has been detected.

2.
Inorg Chem ; 57(9): 4877-4890, 2018 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-29671595

RESUMO

A boron dipyrromethane (BDP)-containing Pt(II)-Schiff base complex (Pt-BDP), showing ping-pong singlet-triplet energy transfer, was synthesized, and the detailed photophysical properties were investigated using various steady-state and time-resolved transient spectroscopies. Femtosecond/nanosecond transient absorption spectroscopies demonstrated that, upon selective excitation of the BDP unit in Pt-BDP at 490 nm, Förster resonance energy transfer from the BDP unit to the Pt(II) coordination center occurred (6.7 ps), accompanied by an ultrafast intersystem crossing at the Pt(II) coordination center (<1 ps) and triplet-triplet energy transfer back to the BDP moiety (148 ps). These processes generated a triplet state localized at BDP, and the lifetime was 103.2 µs, much longer than the triplet-state lifetime of Pt-Ph (3.5 µs), a complex without the BDP moiety. Finally, Pt-BDP was used as a triplet photosensitizer for triplet-triplet annihilation (TTA) upconversion through selective excitation of the BDP unit or the Pt(II) coordination center at lower excitation energy. An upconversion quantum yield of up to 10% was observed with selective excitation of the BDP moiety, and a large anti-Stokes shift of 0.65 eV was observed upon excitation of the lower-energy band of the Pt(II) coordination center. We propose that using triplet photosensitizers with the ping-pong energy-transfer process may become a useful method for increasing the anti-Stokes shift of TTA upconversion.

3.
Angew Chem Int Ed Engl ; 56(12): 3232-3236, 2017 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-28252243

RESUMO

Internally 1,3-phenylene- and 2,5-thienylene-bridged [46]decaphyrins 2 and 3 have been synthesized. While 2 shows modest aromatic character derived from the global 46π-conjugated circuit, 3 displays larger aromatic character owing to the contribution of an (annuleno)annulene-type network consisting of two twisted Möbius aromatic thia[28]hexaphyrin segments in addition to the global 46π-network. Upon protonation, these [46]decaphyrins underwent large structural changes to acquire strong aromaticity. Protonated 3 has been revealed to take on a planar structure composed of fused two triangular thia[28]hexaphyrin segments.

4.
Obstet Gynecol Sci ; 67(3): 304-313, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38368852

RESUMO

OBJECTIVE: This study aimed to determine the clinical advantage of spindle-view intracytoplasmic sperm injection (SVICSI; a novel technology) over conventional intracytoplasmic sperm injection (cICSI) in patients with poor ovarian response (POR) and previous implantation failure. METHODS: The study included 37 patients who underwent SVICSI followed by fresh embryo transfer (FET) at a single fertility clinic from January to December 2022, 58 patients who underwent cICSI followed by FET at the same fertility clinic from January to December 2021 as a control group. All study participants met the Bologna criteria for POR and had at least three or more previous failed embryo transfers. RESULTS: The number of blastocyst transfers was significantly higher in the SVICSI group than in the cICSI group. A good-quality cleavage embryo rate, blastocyst rate, and good-quality blastocyst rate were also significantly higher in the SVICSI group than in the cICSI group. There were no significant differences in the rates of fertilization, implantation, clinical pregnancy, or clinical abortion between the two groups. CONCLUSION: In patients with POR, those who underwent SVICSI appeared to have better embryos than those who underwent cICSI. However, whether SVICSI improved clinical outcomes such as implantation and pregnancy rates cannot be proven.

5.
Chem Sci ; 15(20): 7603-7609, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38784757

RESUMO

Norcorrole derivatives with 3,4,5-trialkoxyphenyl moieties at the meso positions were synthesized to form various stacking assemblies in single crystals and thermotropic liquid crystals (LCs) depending on aliphatic chain lengths. Triple-decker stacking structures were formed via the interactions between the antiaromatic systems formed for the butoxy and dodecyloxy derivatives in the single-crystal and LC states, respectively. In particular, the LC state exhibited discotic columnar structures comprising triple deckers to exhibit high electric conductivity, as supported by molecular dynamics simulations.

6.
J Menopausal Med ; 26(2): 143-146, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32893516

RESUMO

Primary ovarian insufficiency (POI) is defined as the presence of amenorrhea for ≥ 4 months accompanied by evidence of two serum follicle-stimulating hormone levels in the menopausal range in women aged < 40 years. Anti-Müllerian hormone (AMH) has been recognized as the most reliable marker of ovarian reserve status, and its serum level is very low or undetectable in women with POI. Here we report two cases of patients who were diagnosed with POI despite high serum AMH levels and preservation of ovarian follicles, as revealed by ultrasound. In addition, we have presented a review of the current literature regarding this condition.

7.
Dalton Trans ; 49(41): 14383-14387, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33047762

RESUMO

meso-Dimethylnorcorrole NiII complex exhibited enough stability under ambient conditions despite the distinct antiaromaticity. The small methyl substituents realized a dense and long-range π-stacking in its solid state, which resulted in the superior electron-transporting ability to previously reported NiII norcorroles.

8.
Hum Reprod ; 24(5): 1133-41, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19168872

RESUMO

BACKGROUND: P21-activated kinase 1 (Pak1) integrates various signaling pathways that are vital to cell survival and function. This study was performed to evaluate whether sex steroids may regulate the expression of Pak1 in endometrial cells as well as whether its expression is increased in the eutopic endometrium of women with endometriosis. METHODS: Following in vitro estradiol (E(2)) and/or medroxyprogesterone acetate (MPA) treatment of Ishikawa cells and endometrial stromal cells (ESCs), Pak1 protein was analyzed utilizing western blot analysis and immunocytochemistry. Immunohistochemistry was performed to evaluate Pak1 immunoreactivity semiquantitatively in women with endometriosis and in controls. To assess the role of Pak1 on endometrial cell viability, crystal violet assay was performed following transfection of Ishikawa cells with Pak1 small interfering RNA (siRNA). RESULTS: In vitro treatment with E(2) plus MPA or MPA alone led to a significant decrease of Pak1 protein in Ishikawa cells and ESCs (both P < 0.05 versus control). Immunohistochemistry also revealed that Pak1 protein is significantly decreased during the secretory phase in both epithelial and stromal cells in the control subjects (P < 0.001 and P < 0.01, respectively). The immunoreactivity of Pak1 in glandular cells was significantly increased in the eutopic endometrium of women with endometriosis compared with the controls during the secretory phase (P < 0.01). Crystal violet assay has shown that transfection of Ishikawa cells with Pak1 siRNA led to a significant decrease of cellular viability (P < 0.05). CONCLUSIONS: These findings suggest that Pak1 is down-regulated by progesterone during the secretory phase in normal endometrium and increased Pak1 activity during the secretory phase might lead to establishment of endometriosis.


Assuntos
Regulação para Baixo/efeitos dos fármacos , Endometriose/metabolismo , Endométrio/metabolismo , Acetato de Medroxiprogesterona/farmacologia , Progestinas/farmacologia , Quinases Ativadas por p21/genética , Adulto , Linhagem Celular , Estradiol/farmacologia , Feminino , Humanos , Imuno-Histoquímica , Ciclo Menstrual/metabolismo , RNA Interferente Pequeno , Transdução de Sinais/efeitos dos fármacos , Transfecção , Quinases Ativadas por p21/metabolismo
9.
J Reprod Med ; 54(8): 483-7, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19769193

RESUMO

OBJECTIVE: To evaluate the association between serum estradiol (E2) level and intraocular pressure (IOP) in Korean postmenopausal women STUDY DESIGN: From January 2000 to December 2006, serum concentration of E2 and IOP were measured in 8,674 postmenopausal women. Serum concentration of E2 was measured by radioimmunoassay. The IOP was measured using Goldmann's applanation tonometer. All data were analyzed with correlation analysis, Student's t test and analysis of variance. RESULTS: The mean age of the study subjects was 59.57 +/- 8.54 years. The mean E2 concentration was 22.17 +/- 6.08 pg/mL and the mean IOP was 12.23 +/- 2.20 mm Hg for the average of both eyes. In correlation analysis, no significant association was found between IOP and age or IOP and serum E2 concentration. When we divided a total of 8,674 women into 4 groups according to the E2 concentration (< or = 10, 10-20, 20-30 and >30 pg/mL, respectively), the IOPs of the 4 groups did not differ significantly. CONCLUSION: This study suggests that the IOP in Korean postmenopausal women might not be directly associated with serum E2 concentration.


Assuntos
Estradiol/sangue , Pressão Intraocular/fisiologia , Pós-Menopausa/fisiologia , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Tonometria Ocular
10.
Obstet Gynecol Sci ; 59(3): 201-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27200310

RESUMO

OBJECTIVE: To evaluate the effect of hyaluronan-rich transfer medium on pregnancy and implantation rates in fresh and frozen-thawed embryo transfers in Korean women with previous implantation failure. METHODS: This retrospective study included 283 blastocyst transfers in patients with previous embryo transfer failure at a private fertility clinic. In the study group (n=88), blastocyst transfers were performed using an hyaluronan-rich transfer medium prior to transfer, whereas blastocyst transfers without any treatment served as controls (n=195). According to the type of transfer (fresh elective or frozen-thawed), all the blastocyst transfers were divided into two study and two control groups. RESULTS: The patient's mean age, serum anti-Müllerian hormone level, causes of infertility, embryo quality, and the number of transferred embryos were comparable between the study and control groups. There were no significant differences in clinical pregnancy rate (45.5% vs. 43.1%), implantation rate (28.9% vs. 28.8%), and clinical abortion rate (10.0% vs. 8.3%) between the two groups, and these findings were not changed after subgroup analysis according to the type of transfer. CONCLUSION: The use of hyaluronan-rich transfer medium in the blastocyst transfer does not appear to have any significant effect on the implantation and pregnancy rates in patients with previous implantation failure.

11.
Obstet Gynecol Sci ; 56(2): 102-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24327988

RESUMO

OBJECTIVE: This study was performed to compare the expression of CD44 in endometrial stromal cells (ESCs) of women with and without endometriosis and to evaluate the role of CD44 in the adherence of ESCs to peritoneal mesothelial cells (PMCs). METHODS: A PMC adherence assay was performed to evaluate the adherence of ESCs to PMCs in women with and without endometriosis. The expression of CD44 mRNA was measured by reverse transcription-polymerase chain reaction. CD44 protein was evaluated by Western blot analysis. RESULTS: There were no significant differences in the expression of CD44 mRNA and protein in ESCs or in the binding of ESCs to PMCs between patients with endometriosis and controls. Although the expression of CD44 protein was decreased in both women with endometriosis and controls after anti-CD44 antibody treatment, there was no effect on binding of ESCs to PMCs. Treatment of ESCs with peritoneal fluid from endometriosis patients resulted in a significant increase in binding of ESCs to PMCs compared to untreated ESCs in the endometriosis group. CONCLUSION: This study demonstrates that the expression of CD44 protein in ESCs from women with endometriosis might not be directly associated with adherence to PMCs.

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