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1.
Sci Technol Adv Mater ; 25(1): 2327274, 2024.
Article in English | MEDLINE | ID: mdl-38529018

ABSTRACT

Vanadium redox flow batteries (VRFBs) have received significant attention for use in large-scale energy storage systems (ESSs) because of their long cycle life, flexible capacity, power design, and safety. However, the poor electrochemical activity of the conventionally used carbon felt electrode results in low energy efficiency of the VRFBs and consequently impedes their commercialization. In this study, a carbon felt (CF) electrode with numerous nanopores and robust oxygen-containing functional groups at its edge sites is designed to improve the electrochemical activity of a carbon felt electrode. To achieve this, Ni metal nanoparticles were initially precipitated on the surface of the CF electrode, followed by etching of the precipitated Ni nanoparticles on the CF electrode using sulfuric acid. The resulting CF electrode had a specific surface area eight times larger than that of the pristine CF electrode. In addition, the oxygen-containing functional groups anchored at the graphite edge sites of the nanopores can act as robust electrocatalysts for VO2+/VO2+ and V2+/V3+ redox reactions. Consequently, the VRFB cell with the resulting carbon felt electrode can deliver a high energy efficiency of 86.2% at the current density of 60 mA cm-2, which is 20% higher than that of the VRFB cell with the conventionally heat-treated CF electrode. Furthermore, the VRFB cell with the resultant carbon felt electrodes showed stable cycling performance with no considerable energy efficiency loss over 200 charge-discharge cycles. In addition, even at a high current density of 160 mA cm-2 , the developed carbon felt electrode can achieve an energy efficiency of 70.1%.


This work reveals the importance of the robust graphite edge-site oxygen functional group and the holey structure of the ET-CF electrode, emphasizing that high VRFB efficiency can be achieved by engineering both the structure and surface properties of the carbon felt electrode.

2.
Tissue Eng Regen Med ; 20(7): 1133-1143, 2023 12.
Article in English | MEDLINE | ID: mdl-37610706

ABSTRACT

BACKGROUND: Cryopreservation is a crucial method for long-term storage and stable allocation of human pluripotent stem cells (hPSCs), which are increasingly being used in various applications. However, preserving hPSCs in cryogenic conditions is challenging due to reduced recovery rates. METHODS: To address this issue, the Arginine-Glycine-Aspartate (RGD) motif was incorporated into a recombinant elastin-like peptide (REP). Human embryonic stem cells (hESCs) were treated with REP containing RGD motif (RGD-REP) during suspension and cryopreservation, and the survival rate was analyzed. The underlying mechanisms were also investigated. RESULTS: The addition of RGD-REP to the cryopreservation solution improved cell survival and pluripotency marker expression. The improvement was confirmed to be due to the activation of the FAK-AKT cascade by RGD-REP binding to hESC surface interin protein, and consequent inhibition of FoxO3a. The inactivation of FoxO3a reduced the expression of apoptosis-related genes, such as BIM, leading to increased survival of PSCs in a suspension state. CONCLUSION: RGD-REP, as a ligand for integrin protein, improves the survival and maintenance of hPSCs during cryopreservation by activating survival signals via the RGD motif. These results have potential implications for improving the efficiency of stem cell usage in both research and therapeutic applications.


Subject(s)
Human Embryonic Stem Cells , Pluripotent Stem Cells , Humans , Human Embryonic Stem Cells/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Elastin/metabolism , Cryopreservation/methods , Signal Transduction , Oligopeptides/pharmacology
3.
Foods ; 10(1)2021 Jan 18.
Article in English | MEDLINE | ID: mdl-33477405

ABSTRACT

Menopause leads to ovarian hormone loss, which causes symptoms such as weight gain, hot flashes, and depression. Exploring nutraceuticals is important for treating menopausal symptoms that extensively impact women's quality of life. We hypothesized that a combination of Leonurus japonicus Houtt, Eclipta prostrata L., and Pueraria lobata Ohwi (LEPE) would alleviate menopausal symptoms in an ovariectomized menopausal rat model. Bilateral ovariectomy was performed and animals were assigned to five groups: (1) Sham, (2) Vehicle, (-) Control, (3) LEPE (100 mg/kg bw), (4) LEPE (200 mg/kg bw), and (5) Estradiol (3 µg/kg bw). LEPE was orally administered daily for 12 weeks. LEPE supplementation did not affect growth performance (body weight and feed intake) or body composition (lean mass and fat in tissue). LEPE did not cause deviations in aspartate aminotransferase, alanine aminotransferase, estradiol, and follicle-stimulating hormone levels, indicating no hepatotoxicity or endocrine disturbance. LEPE decreased type I collagen (CTX-1) but did not affect bone mineral density or osteocalcin. LEPE decreased tail temperature and increased rectal temperature, improving menopause-related vasomotor symptoms. Furthermore, LEPE ameliorated depression-related behavior, including in forced swimming and tail suspension tests. Thus, LEPE may improve menopausal symptoms by enhancing vasomotor symptoms and depression in an ovariectomized rat menopause model.

4.
Gynecol Endocrinol ; 36(7): 599-604, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32321334

ABSTRACT

To verify the different expression of G protein-coupled estrogen receptor 1 (GPER1) among normal uterine, leiomyoma, and adenomyosis tissues. Normal uterine, leiomyoma, and adenomyosis tissue samples were obtained from women aged 35-52 years from a tertiary university hospital. The tissue samples were subjected to immunohistochemical, Western blot, and reverse-transcription polymerase chain reaction (RT-PCR) analyses of GPER1. GPER1 protein expression was confirmed in the tissues by immunohistochemical and Western blot analyses and compared with GPER1 mRNA levels using RT-PCR. GPER1 was detected in the tissue samples of leiomyoma and adenomyosis, which are estrogen-dependent diseases. GPER1 expression was similar between normal uterine and leiomyoma tissues but was reduced in adenomyosis tissue. The level of phosphorylated extracellular signal-regulated kinases 1/2 was lower and higher in leiomyoma and adenomyosis tissues, respectively, than in normal tissue, but the differences among the groups were not statistically significant. Our immunohistochemical, Western blot, and RT-PCR results suggest that GPER1 expression is involved in cell proliferation in leiomyoma and in cell invasion and migration in adenomyosis. Functional studies of GPER1 involving larger sample sizes should be performed to confirm the adenomyosis and leiomyoma disease mechanisms and eventually to develop new therapeutic interventions for these diseases.


Subject(s)
Adenomyosis/genetics , Leiomyoma/genetics , Myometrium/metabolism , Receptors, Estrogen/genetics , Receptors, G-Protein-Coupled/genetics , Uterine Neoplasms/genetics , Adenomyosis/metabolism , Adenomyosis/pathology , Adult , Case-Control Studies , Female , Gene Expression , Humans , Immunohistochemistry , Leiomyoma/metabolism , Leiomyoma/pathology , Middle Aged , Myometrium/pathology , Receptors, Estrogen/metabolism , Receptors, G-Protein-Coupled/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Uterine Neoplasms/metabolism , Uterine Neoplasms/pathology , Uterus/metabolism , Uterus/pathology
5.
J Bone Metab ; 26(3): 169-177, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31555614

ABSTRACT

BACKGROUND: The molecular pathways of how endocrine disruptors affect bone mineral density (BMD) and bone remodeling are still unclear. The purpose of this experimental study is to determine the effects of di(2-ethylhexyl)phthalate (DEHP) on bone metabolism in ovariectomized mice. METHODS: Twenty-six-month-old female CD-1 mice were divided into 4 groups: control, low-dose DEHP, high-dose DEHP, and estrogen groups (n=5, each group). All mice were subjected to ovariectomy for the induction of artificial menopause and then exposed to corn oil, DEHP, and estrogen for 2 months. Micro-computed tomography (Micro-CT) of the bone and analysis of blood samples for bone markers were performed to observe the changes in bone metabolism. RESULTS: Osteocalcin level was decreased in the control, low-dose and high-dose DEHP group, the reduction width was greater in the high-dose DEHP group (-0.219 ng/mL) than control group (-0.077 ng/mL, P<0.05). C-terminal telopeptide of type I collagen level was increased in the control, low-dose and high-dose DEHP group, the increase range of low-dose DEHP group (0.329 ng/mL) showed greater than control group (0.093 ng/mL, P<0.05). Micro-CT analysis revealed that the BMD was significantly lower in the high-dose DEHP group (19.8×10-2 g/cm3) than control group (27.2×10-2 g/cm3, P<0.05). The structure model index was significantly higher in the high-dose DEHP group (2.737) than low-dose DEHP group (2.648) and estrogen group (2.63, P<0.05). It means the progression of osteoporosis in the high-dose DEHP group. CONCLUSIONS: These results confirm the negative effects of DEHP on bone health in ovariectomized mice. Further continuous studies on genetic pathways and other endocrine disruptors will be necessary to validate these findings.

6.
Article in English | MEDLINE | ID: mdl-29210600

ABSTRACT

In recent years, silver nanoparticles (AgNPs) have been extensively employed in food packaging systems as a potential antibacterial agent. Although proven to be highly effective, the increased number of AgNP-containing products raises concerns among consumers regarding the migration of AgNPs from the packaging material into foods, which may exert toxic effects. To address this, five baby products were chosen (baby bottle A, baby bottle B, pacifier A, pacifier B and breastmilk storage bag) to investigate AgNPs migration into three food simulants (deionised water, 4% acetic acid (w/v) and 50% ethanol (v/v)) using inductively coupled plasma mass spectrometry (ICP-MS). As a result, the highest level of migrated Ag was observed for 4% acetic acid in the case of baby bottle B, pacifier A, pacifier B and the breastmilk storage bag, with the detection amount ranging from 1.05-2.25 ng/mL. On the other hand, baby bottle A showed the maximum migration for 50% ethanol due to the polymer nature. Finally, a centrifugal ultrafiltration experiment was conducted to determine the fraction of dissolved Ag in acidic simulant and it was found that migrated Ag was predominantly in Ag+ form, with a small fraction of non-ionic AgNPs. Thus, it has been found that the amount of migrated Ag in baby products was low; however, the migration was dependent on the type of food simulant and polymer nature.


Subject(s)
Food Contamination/analysis , Food Packaging/methods , Infant Formula/chemistry , Metal Nanoparticles/analysis , Polymers/chemistry , Silver/analysis , Consumer Product Safety , Humans , Infant
7.
Taiwan J Obstet Gynecol ; 56(4): 482-486, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28805605

ABSTRACT

OBJECTIVE: We used data from the 2011-2014 Korean National Health and Nutrition Examination Surveys (KNHANES) to investigate whether the age at menopause is related to alcohol consumption in South Korean women. MATERIALS AND METHODS: This was a cross-sectional study of the data for 940 women who became menopausal within the 3 years preceding the KNHANES. RESULTS: The numbers of nondrinkers, mild to moderate drinkers, and heavy drinkers in this group were 345 (34.7%), 573 (62.2%), and 22 (3%). Body mass index (BMI), smoking, and exercise were adjusted in model 1 and age was additionally adjusted in model 2. The mean ages at menopause were 51.6 ± 0.2, 50.8 ± 0.1, and 50.4 ± 0.5 years (p = 0.0025) in model 1 and 51.7 ± 0.2, 51.1 ± 0.1, and 50.1 ± 0.5 years (p = 0.0018) in model 2 for nondrinkers, mild to moderate drinkers, and heavy drinkers, respectively. BMI, smoking, exercise, educational level, income, duration of menopause, age at menarche, age at first delivery, and gravidity were adjusted in model 3, and the respective mean ages at menopause were 51.3 ± 0.2, 50.7 ± 0.2, and 50.1 ± 0.8 years (p = 0.0402). The population was classified into groups using the Alcohol Use Disorders Identification Test (AUDIT) scores of <5 (n = 778), <10 (n = 108), and ≥10 score (n = 54). The mean ages at menopause according to AUDIT score were 51.3 ± 0.1, 50.5 ± 0.3, and 50.4 ± 0.4 years (p = 0.0222, model 1), 51.4 ± 0.1, 50.8 ± 0.3, and 50.8 ± 0.3 years (p = 0.0261, model 2), and 51.1 ± 0.1, 50.6 ± 0.4, and 49.5 ± 0.6 years (p = 0.0241, model 3) respectively. CONCLUSION: In Korean women, alcohol consumption was associated with younger age at menopause. A higher AUDIT score was also related to younger age at menopause.


Subject(s)
Age Factors , Alcohol Drinking/adverse effects , Menopause , Body Mass Index , Cross-Sectional Studies , Exercise , Female , Humans , Middle Aged , Nutrition Surveys , Republic of Korea , Risk Factors , Smoking , Socioeconomic Factors
8.
Obstet Gynecol Sci ; 60(4): 362-368, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28791268

ABSTRACT

OBJECTIVE: We used data from the 2010 to 2012 Korean National Health and Nutrition Examination Surveys to investigate whether the age at menopause is related to age at last delivery. METHODS: This was a cross-sectional study of the data for 714 women who became menopausal within the 3 years preceding the Korean National Health and Nutrition Examination Survey. RESULTS: Smoking, exercise, drink, educational level, and income were adjusted in model 1, and the mean ages at menopause were 50.5±0.3, 51.2±0.2, 51.2±0.3, and 50.2±0.4 years for women with <25, ≥25 and <30, ≥30 and <35, ≥35 years age at last delivery, respectively (P=0.049). Smoking, exercise, drink, educational level, income, age at first delivery, age at last delivery, and gravidity were adjusted in model 2, and the respective mean ages at menopause were 50.5±0.5, 50.7±0.4, 50.3±0.4, and 49.2±0.5 years (P=0.03). In both models, older age at last delivery showed higher age at menopause compared with women with younger age at last delivery. CONCLUSION: Korean women with older age at last delivery were associated with younger age at menopause. Increased number of pregnancies was related to older age at menopause.

9.
J Menopausal Med ; 23(1): 25-31, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28523256

ABSTRACT

OBJECTIVES: The aim of this study was to determine the relationship of ovarian volume (OV) to age, height, and weight in Korean young women with the polycystic ovary syndrome (PCOS) undergoing ultrasonography (US) and to investigate the relationship between ovarian follicle count and volume on US and serum hormone levels including the levels of the anti-Müllerian hormone (AMH) and gonadotropin. METHODS: A total of 272 Korean nulliparous women aged 15 to 39 years who were newly diagnosed with PCOS at a university hospital were included in this study. Evaluation of the ovaries and measurement of OVs in all cases were randomly performed by ultrasound. The OV and follicle number (FN) were obtained in all cases. RESULTS: In Korean women with PCOS, mean OV was 7.9 ± 3.6 cm3 (right) and 6.7 ± 3.1 cm3 (left). Mean FN in the PCOS group was 14.2 ± 4.6 (right) and 13.8 ± 4.3 (left). OV and ovarian FN were unrelated to patient weight, height and body mass index. The left ovarian FN was related to patient age. AMH levels ranged from 5.31 to 43.1 ng/mL and the mean level was 13.9 ± 7.2 ng/mL. Serum AMH was related to OV and FN, and serum total testosterone was related to FN in Korean women with PCOS. CONCLUSIONS: In Korean nulliparous women with PCOS, OV was smaller than that in other ethnic groups and the right OV was larger than the left OV. Ovarian FN, AMH, testosterone are good markers for the diagnosis of PCOS in Korean women.

10.
Maturitas ; 92: 24-29, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27621234

ABSTRACT

OBJECTIVES: The study investigated the association between childbirth history and health-related quality of life (QOL) in menopausal South Korean women. STUDY DESIGN: Cross-sectional analysis of data from the 2010-2012 Korean National Health and Nutrition Examination Surveys (KNHANES) for 4277 menopausal women aged over 50. We used the EuroQol index to measure health-related QOL. MAIN OUTCOME MEASURES: The relationship between delivery history and health-related QOL in menopausal South Korean women was analyzed. RESULTS: After adjustment for age (model 1), women who were younger at their first delivery and who had a greater number of deliveries had a significantly higher risk of problems with mobility, self-care, usual activities and pain or discomfort; the risk of anxiety or depression was not increased. After adjustment for age, BMI, smoking, use of alcohol, exercise, income, education, marital status, metabolic syndrome and stress (model 2), women who were younger at their first delivery and who had a greater number of deliveries had a significantly higher risk of problems with mobility, self-care and pain or discomfort. Age at last delivery was not significantly associated with health-related QOL in either model. CONCLUSIONS: South Korean women who were younger at their first delivery and who had more deliveries appear to be at increased risk of health-related QOL problems after menopause.


Subject(s)
Menopause , Parity , Quality of Life , Reproductive History , Adult , Age Factors , Aged , Cross-Sectional Studies , Exercise , Female , Health Status , Humans , Marital Status , Middle Aged , Models, Theoretical , Nutrition Surveys , Republic of Korea , Self Care , Smoking
11.
PLoS One ; 11(5): e0155052, 2016.
Article in English | MEDLINE | ID: mdl-27148873

ABSTRACT

OBJECTIVE: To identify the proteins involved the compensatory adaptive response to paclitaxel in ovarian cancer cells and to determine whether inhibition of the compensatory adaptive response increases the efficacy of paclitaxel in decreasing the viability of cancer cells. METHODS: We used a reverse-phase protein array and western blot analysis to identify the proteins involved in the compensatory mechanism induced by paclitaxel in HeyA8 and SKOV3 ovarian cancer cells. We used a cell viability assay to examine whether inhibition of the proteins involved in the compensatory adaptive response influenced the effects of paclitaxel on cancer cell viability. All experiments were performed in three-dimensional cell cultures. RESULTS: Paclitaxel induced the upregulation of pS6 (S240/S244) and pS6 (S235/S236) in HeyA8 and SKOV3 cells, and pPRAS40 (T246) in HeyA8 cells. BX795 and CCT128930 were chosen as inhibitors of pS6 (S240/S244), pS6 (S235/S236), and pPRAS40 (T246). BX795 and CCT128930 decreased pS6 (S240/S244) and pS6 (S235/S236) expression in HeyA8 and SKOV3 cells. However, pPRAS40 (T246) expression was inhibited only by BX795 and not by CCT128930 in HeyA8 cells. Compared with paclitaxel alone, addition of BX795 or CCT128930 to paclitaxel was more effective in decreasing the viability of HeyA8 and SKOV3 cells. CONCLUSION: Addition of BX795 or CCT128930 to inhibit pS6 (S240/S244) or pS6 (S235/S236) restricted the compensatory adaptive response to paclitaxel in HeyA8 and SKOV3 cells. These inhibitors increased the efficacy of paclitaxel in reducing cancer cell viability.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Cell Survival/drug effects , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/metabolism , Paclitaxel/pharmacology , Ribosomal Protein S6 Kinases/metabolism , Cell Line, Tumor , Female , Humans , Signal Transduction/drug effects , Up-Regulation/drug effects
12.
Case Rep Obstet Gynecol ; 2016: 1987690, 2016.
Article in English | MEDLINE | ID: mdl-26998371

ABSTRACT

Accidental genital trauma is most commonly caused by straddle-type injuries and is usually treatable by nonoperative management, and most of the injuries have a good prognosis. When the bleeding occurred due to straddle injury in adolescent girl, experienced gynecological examination and treatment were very important. We experienced a case of straddle injury to the posterior fourchette that caused acute hematocolpos due to delayed adequate treatment with hypotension and acute abdomen in an adolescent girl. This case shows the importance of careful and accurate physical and gynecological examination and adequate and prompt treatment of genital trauma in adolescent girls.

13.
Case Rep Obstet Gynecol ; 2015: 761348, 2015.
Article in English | MEDLINE | ID: mdl-26345735

ABSTRACT

Ureteral involvement by endometriosis is a rare and often silent disease but capable of producing significant morbidity and leading to hydronephrosis and to renal failure. Surgery is the treatment of choice to remove endometriotic lesions and relieve ureteral obstruction if the kidney is still functional or a nephrectomy is performed if there is a complete loss of renal function. We report a case of acute renal failure induced ureteral endometriosis managed with laparoscopic unilateral nephrectomy and endometrioma cystectomy. Differential diagnosis is important to confirm diagnosis for patients with ureteral obstruction presenting nonspecific symptoms.

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