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1.
Nanomaterials (Basel) ; 14(9)2024 May 01.
Article in English | MEDLINE | ID: mdl-38727385

ABSTRACT

In this study, a Y2O3 insulator was fabricated via the sol-gel process and the effect of precursors and annealing processes on its electrical performance was studied. Yttrium(III) acetate hydrate, yttrium(III) nitrate tetrahydrate, yttrium isopropoxide oxide, and yttrium(III) tris (isopropoxide) were used as precursors, and UV/ozone treatment and high-temperature annealing were performed to obtain Y2O3 films from the precursors. The structure and surface morphologies of the films were characterized via grazing-incidence X-ray diffraction and scanning probe microscopy. Chemical component analysis was performed via X-ray spectroscopy. Electrical insulator characteristics were analyzed based on current density versus electrical field data and frequency-dependent dielectric constants. The Y2O3 films fabricated using the acetate precursor and subjected to the UV/ozone treatment showed a uniform and flat surface morphology with the lowest number of oxygen vacancy defects and unwanted byproducts. The corresponding fabricated capacitors showed the lowest current density (Jg) value of 10-8 A/cm2 at 1 MV/cm and a stable dielectric constant in a frequency range of 20 Hz-100 KHz. At 20 Hz, the dielectric constant was 12.28, which decreased to 10.5 at 105 Hz. The results indicate that high-quality, high-k insulators can be fabricated for flexible electronics using suitable precursors and the suggested low-temperature fabrication methods.

2.
Nanomaterials (Basel) ; 14(6)2024 Mar 16.
Article in English | MEDLINE | ID: mdl-38535680

ABSTRACT

Herein, sol-gel-processed Y2O3 resistive random-access memory (RRAM) devices were fabricated. The top electrodes (TEs), such as Ag or Cu, affect the electrical characteristics of the Y2O3 RRAM devices. The oxidation process, mobile ion migration speed, and reduction process all impact the conductive filament formation of the indium-tin-oxide (ITO)/Y2O3/Ag and ITO/Y2O3/Cu RRAM devices. Between Ag and Cu, Cu can easily be oxidized due to its standard redox potential values. However, the conductive filament is easily formed using Ag TEs. After triggering the oxidation process, the formed Ag mobile metal ions can migrate faster inside Y2O3 active channel materials when compared to the formed Cu mobile metal ions. The fast migration inside the Y2O3 active channel materials successfully reduces the SET voltage and improves the number of programming-erasing cycles, i.e., endurance, which is one of the nonvolatile memory parameters. These results elucidate the importance of the electrochemical properties of TEs, providing a deeper understanding of how these factors influence the resistive switching characteristics of metal oxide-based atomic switches and conductive-metal-bridge-filament-based cells.

3.
Nanomaterials (Basel) ; 13(17)2023 Aug 27.
Article in English | MEDLINE | ID: mdl-37686940

ABSTRACT

Yttrium oxide (Y2O3) resistive random-access memory (RRAM) devices were fabricated using the sol-gel process on indium tin oxide/glass substrates. These devices exhibited conventional bipolar RRAM characteristics without requiring a high-voltage forming process. The effect of current compliance on the Y2O3 RRAM devices was investigated, and the results revealed that the resistance values gradually decreased with increasing set current compliance values. By regulating these values, the formation of pure Ag conductive filament could be restricted. The dominant oxygen ion diffusion and migration within Y2O3 leads to the formation of oxygen vacancies and Ag metal-mixed conductive filaments between the two electrodes. The filament composition changes from pure Ag metal to Ag metal mixed with oxygen vacancies, which is crucial for realizing multilevel cell (MLC) switching. Consequently, intermediate resistance values were obtained, which were suitable for MLC switching. The fabricated Y2O3 RRAM devices could function as a MLC with a capacity of two bits in one cell, utilizing three low-resistance states and one common high-resistance state. The potential of the Y2O3 RRAM devices for neural networks was further explored through numerical simulations. Hardware neural networks based on the Y2O3 RRAM devices demonstrated effective digit image classification with a high accuracy rate of approximately 88%, comparable to the ideal software-based classification (~92%). This indicates that the proposed RRAM can be utilized as a memory component in practical neuromorphic systems.

4.
Nanomaterials (Basel) ; 13(17)2023 Aug 31.
Article in English | MEDLINE | ID: mdl-37686969

ABSTRACT

Herein, sol-gel-processed Y2O3-Al2O3 mixed oxide-based resistive random-access-memory (RRAM) devices with different proportions of the involved Y2O3 and Al2O3 precursors were fabricated on indium tin oxide/glass substrates. The corresponding structural, chemical, and electrical properties were investigated. The fabricated devices exhibited conventional bipolar RRAM characteristics without requiring a high-voltage forming process. With an increase in the percentage of Al2O3 precursor above 50 mol%, the crystallinity reduced, with the amorphous phase increasing owing to internal stress. Moreover, with increasing Al2O3 percentage, the lattice oxygen percentage increased and the oxygen vacancy percentage decreased. A 50% Y2O3-50% Al2O3 mixed oxide-based RRAM device exhibited the maximum high-resistance-state/low-resistance-state (HRS/LRS) ratio, as required for a large readout margin and array size. Additionally, this device demonstrated good endurance characteristics, maintaining stability for approximately 100 cycles with a high HRS/LRS ratio (>104). The HRS and LRS resistances were also retained up to 104 s without considerable degradation.

5.
Medicina (Kaunas) ; 58(3)2022 Feb 23.
Article in English | MEDLINE | ID: mdl-35334511

ABSTRACT

Rhizomes of Cyperus rotundus have been widely used as a traditional medicine in Asia for the treatment of gynecological diseases. However, there is no scientific evidence demonstrating the effect of C. rotundus rhizomes on endometriosis, which is characterized by the adhesion of endometrial tissues outside the uterus, resulting in chronic and severe pelvic pain. The aim of this study was to investigate the effects of Cyperi rhizoma extract (CRE) on cell adhesion and the expression of pain-related factors (neurotrophins) in endometriotic cells, and to elucidate the underlying molecular mechanisms. CRE inhibited the adhesion of human endometriotic 12Z cells to peritoneal mesothelial Met5A cells using by adhesion assays. The mRNA expression of adhesion molecules [P-cadherin and matrix metalloproteinase (MMP)-2] was downregulated by CRE treatment. In addition, CRE significantly inhibited the mRNA expression of neurotrophins (BDNF, NGF, NT-3 and NT-4/5) in 12Z cells. Moreover, Akt overexpression markedly neutralized the inhibition of cell adhesion by CRE and expression of neurotrophins in 12Z cells. Furthermore, it was found that CRE suppressed NF-kB activation through the Akt pathway. These data suggest that CRE exerts anti-endometriotic activities by the inhibition of cell adhesion and neurotrophin expression, through the negative regulation of the Akt and NF-kB pathways in endometriotic cells.


Subject(s)
Cyperus/chemistry , Endometriosis , NF-kappa B , Plant Extracts , Proto-Oncogene Proteins c-akt , Cell Adhesion , Cells, Cultured , Endometriosis/complications , Endometriosis/drug therapy , Endometriosis/metabolism , Female , Humans , Pain , Plant Extracts/pharmacology , Rhizome/chemistry , Signal Transduction
6.
Clin Hypertens ; 27(1): 21, 2021 Nov 01.
Article in English | MEDLINE | ID: mdl-34719392

ABSTRACT

BACKGROUND: In this prospective, multicenter, non-comparative observational study, the effectiveness and safety of the triple single-pill combination (SPC) of olmesartan/amlodipine/hydrochlorothiazide (OM/AML/HCTZ) were evaluated in a real clinical practice setting in Korean patients with essential hypertension. METHODS: A total of 3752 patients were enrolled and followed for 12 months after administration of OM/AML/HCTZ. Primary endpoint was change from baseline to month 6 in the mean systolic blood pressure (SBP). Secondary endpoints included changes from baseline in the mean SBP at month 3, 9, 12 and the mean diastolic blood pressure (DBP) at month 3, 6, 9, 12; changes in the mean SBP/DBP according to age and underlying risk factors; and blood pressure control rate (%) at different time points. Adherence to and satisfaction with OM/AML/HCTZ treatment among patients and physicians were assessed by medication possession ratio (MPR) and numeric rating scale, respectively, as exploratory endpoints. Safety was evaluated by the incidence and severity of adverse events (AEs) as well as the discontinuation rate due to AEs. RESULTS: OM/AML/HCTZ administration led to significant reductions in the mean SBP/DBP by 11.5/6.6, 12.3/7.0, 12.3/7.2, and 12.8/7.4 mmHg from baseline to month 3, 6, 9 and 12, respectively (P < 0.0001). The BP reductions were maintained throughout the 1-year observation period in all patients with different age groups and risk factors (diabetes mellitus, cardiovascular disease, and renal disease). The BP control rate (%) of < 140/90 mmHg was 65.9, 67.9, 68.9, and 70.6% at month 3, 6, 9, and 12, respectively. The mean MPR during the observation period was 0.96. The safety results were consistent with the previously reported safety profile of OM/AML/HCTZ. CONCLUSIONS: Treatment with the triple SPC of OM/AML/HCTZ demonstrated significant effectiveness in reducing SBP/DBP and achieving target BP control with high adherence over the 1-year observation period in Korean hypertensive patients and was well-tolerated. TRIAL REGISTRATION: CRIS, KCT0002196 , Registered 3 May 2016.

7.
Obstet Gynecol Sci ; 61(5): 584-589, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30254994

ABSTRACT

OBJECTIVE: Gynecologic oncologists are uncertain about the safety of tibolone application in cervical adenocarcinoma (AC) patients. This study examined the possible adverse effects of tibolone on the survival of cervical AC patients. METHODS: Medical records of 70 cervical AC patients with International Federation of Gynecology and Obstetrics stages IA to IB were reviewed. A bilateral salpingo-oophorectomy was performed in all patients, and survival outcomes between tibolone users (n=38) and non-users (n=32) were compared. RESULTS: A comparison of the tibolone users with non-users revealed similar clinicopathological variables. Progression-free survival (P=0.34) and overall survival (P=0.22) were similar in the users and non-users. The risks of progression (hazard ratio [HR], 1.71; 95% confidence interval [CI], 0.46-6.37; P=0.43) and death (HR, 1.59; 95% CI, 0.06-45.66; P=0.79) were also similar in both groups. CONCLUSION: Tibolone has no adverse effect on the survival of cervical AC patients and can be administered safely to this population. These findings may be helpful in improving the quality of life of cervical AC patients.

8.
Rheumatol Int ; 38(10): 1941-1948, 2018 Oct.
Article in English | MEDLINE | ID: mdl-29959468

ABSTRACT

Immunoglobulin G4-related disease (IgG4-RD) is a chronic, immune-mediated-, systemic disease that is characterized by IgG4 plasma cell infiltration with fibrotic changes in various organs. The most affected organs are pancreas and salivary glands. Kidney can be rarely involved, and is usually represented as a renal mass and organomegaly. Usually, elevated levels of serum IgG4 more than 135 mg/dl with organ-specific features and biopsy results showing enriched infiltration of IgG4-positive plasma cells are needed to diagnose the disease. However, we experienced two unusual cases of IgG4-RD involving kidney. IgG4-related kidney disease (IgG4-RKD) was first reported as an extra pancreatic feature of autoimmune pancreatitis(AIP) in 2004. Herein, we describe two cases of such unique presentation of IgG4RKD and a literature review focusing on clinicopathologic features of IgG4RKD. Our cases are distinct in the fact that IgG4RD invades unusual organs such as perinephric capsule or scrotum. We reported the patient who showed extinct perirenal capsule invasion with multi-organ involvement including exocrine glands in comparison to previous IgG4RKD that often involved in renal parenchyma and renal pelvis lesions. And the other patient had scrotal invasion with multifocal renal parenchymes. Referring to the features observed in these two cases, we could propose that as every organ can be related to IgG4RD, we propose clinicians to confirm the disease using imaging, serologic, and pathologic studies. We also reviewed previous reports of IgG4-RKD and summarized diverse imaging findings and pathologic features.


Subject(s)
Autoimmune Diseases/complications , Immunoglobulin G/immunology , Kidney Diseases/immunology , Autoimmune Diseases/immunology , Humans , Immunoglobulin G/blood , Kidney Diseases/pathology , Male , Pancreas , Pancreatitis
9.
J Ethnopharmacol ; 169: 426-34, 2015 Jul 01.
Article in English | MEDLINE | ID: mdl-25940205

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Eclipta prostrate L. (syn. E. alba Hassk), commonly known as False Daisy, has been used in traditional medicine in Asia to treat a variety of diseases, including cancer. Although an anti-tumor effect has been suggested for E. prostrata, the exact anti-tumor effects and underlying molecular mechanisms of its bioactive compounds are poorly understood. The aim of this study was to identify compounds with anti-cancer activity from E. prostrata and to investigate their mechanism of action. MATERIALS AND METHODS: To assess cell viability, cell cycle progression, and apoptosis, we performed MTT assays and FACS analysis using Annexin and PI staining. We also investigated reactive oxygen species (ROS) production and caspase activation using flow cytometry and Western blot analysis, respectively. Cytosolic translocation of cytochrome c was measured using an ELISA kit. Antioxidants, MAPK signaling inhibitors, NADPH oxidase inhibitors, and siRNA were used to elucidate the molecular mechanism of action of the compound. RESULTS: We isolated five terthiophenes from the n-hexane fraction of E. prostrata; of these, α-terthienylmethanol possessed potent cytotoxic activity against human endometrial cancer cells (Hec1A and Ishikawa) (IC50<1µM). The growth inhibitory effect of α-terthienylmethanol was mediated by the induction of apoptosis, as shown by the accumulation of sub-G1 and apoptotic cells. In addition, α-terthienylmethanol triggered caspase activation and cytochrome c release into the cytosol in a time-dependent manner. Moreover, α-terthienylmethanol increased the intracellular level of ROS and decreased that of GSH, and the antioxidants N-acetyl-l-cysteine and catalase significantly attenuated α-terthienylmethanol-induced apoptosis. We further demonstrated that inhibition of the NADPH oxidase attenuated α-terthienylmethanol-induced cell death and ROS accumulation in endometrial cancer cells. CONCLUSION: Overall, these results suggest that α-terthienylmethanol, a naturally occurring terthiophene isolated from E. prostrata, induces apoptosis in human endometrial cancer cells by ROS production, partially via NADPH oxidase.


Subject(s)
Apoptosis/drug effects , Eclipta/chemistry , Endometrial Neoplasms/metabolism , Endometrial Neoplasms/pathology , NADPH Oxidases/metabolism , Reactive Oxygen Species/metabolism , Thiophenes/pharmacology , Caspases/metabolism , Cell Cycle/drug effects , Cell Line, Tumor , Cell Survival/drug effects , Cytochromes c/metabolism , Endometrial Neoplasms/enzymology , Female , Glutathione/metabolism , Humans , NADPH Oxidases/antagonists & inhibitors , Signal Transduction/drug effects , Thiophenes/isolation & purification
10.
Blood ; 123(22): 3406-13, 2014 May 29.
Article in English | MEDLINE | ID: mdl-24615776

ABSTRACT

Idelalisib (GS-1101, CAL-101), an oral inhibitor of phosphatidylinositol 3-kinase-δ, was evaluated in a phase I study in 64 patients with relapsed indolent non-Hodgkin lymphoma (iNHL). Patients had a median (range) age of 64 (32-91) years, 34 (53%) had bulky disease (≥1 lymph nodes ≥5 cm), and 37 (58%) had refractory disease. Patients had received a median (range) of 4 (1-10) prior therapies. Eight dose regimens of idelalisib were evaluated; idelalisib was taken once or twice daily continuously at doses ranging from 50 to 350 mg. After 48 weeks, patients still benefitting (n = 19; 30%) enrolled into an extension study. Adverse events (AEs) occurring in 20% or more patients (total%/grade ≥3%) included diarrhea (36/8), fatigue (36/3), nausea (25/3), rash (25/3), pyrexia (20/3), and chills (20/0). Laboratory abnormalities included neutropenia (44/23), anemia (31/5), thrombocytopenia (25/11), and serum transaminase elevations (48/25). Twelve (19%) patients discontinued therapy due to AEs. Idelalisib induced disease regression in 46/54 (85%) of evaluable patients achieving an overall response rate of 30/64 (47%), with 1 patient having a complete response (1.6%). Median duration of response was 18.4 months, median progression-free survival was 7.6 months. Idelalisib is well tolerated and active in heavily pretreated, relapsed/refractory patients with iNHL. These trials were registered at clinicaltrials.gov as NCT00710528 and NCT01090414.


Subject(s)
Antineoplastic Agents/therapeutic use , Lymphoma, Non-Hodgkin/drug therapy , Phosphoinositide-3 Kinase Inhibitors , Purines/therapeutic use , Quinazolinones/therapeutic use , Adult , Aged , Aged, 80 and over , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/adverse effects , Antineoplastic Agents/pharmacokinetics , Female , Humans , Lymphoma, Non-Hodgkin/diagnosis , Lymphoma, Non-Hodgkin/mortality , Male , Middle Aged , Neoplasm Grading , Purines/administration & dosage , Purines/adverse effects , Purines/pharmacokinetics , Quinazolinones/administration & dosage , Quinazolinones/adverse effects , Quinazolinones/pharmacokinetics , Salvage Therapy , Treatment Outcome
11.
Blood ; 123(22): 3398-405, 2014 May 29.
Article in English | MEDLINE | ID: mdl-24615778

ABSTRACT

Idelalisib, an oral inhibitor of phosphatidylinositol-3-kinase δ (PI3Kδ), was evaluated in a 48-week phase 1 study (50-350 mg daily or twice daily) enrolling 40 patients with relapsed or refractory mantle cell lymphoma (MCL). Primary outcome was safety and dose-limiting toxicity (DLT). Secondary outcomes were pharmacokinetic parameters, pharmacodynamic effects, overall response rate (ORR), progression-free survival (PFS), and duration of response (DOR). Patients without DLT and no evidence of disease progression after 48 weeks enrolled in the extension study. Patients had median age of 69 years (range, 52-83) and received median of 4 prior therapies (1-14); 17 of 40 patients (43%) were refractory to their most recent treatment. Median duration of idelalisib treatment was 3.5 months (range, 0.7-30.7), with 6 (15%) continuing extension treatment. Common grade ≥3 adverse events (AEs) included (total%/grade ≥3%) diarrhea (40/18), nausea (33/5), pyrexia (28/0), fatigue (25/3), rash (23/3), decreased appetite (20/15), upper respiratory infection (20/0), pneumonia (13/10), and alanine transaminase or aspartate transaminase elevations (60/20). ORR was 16 of 40 patients (40%), with CR in 2 of 40 patients (5%). Median DOR was 2.7 months, median PFS was 3.7 months, and 1-year PFS was 22%. These data provide proof of concept that targeting PI3Kδ is a viable strategy and worthy of additional study in MCL. This trial was registered at www.clinicaltrials.gov as #NCT00710528.


Subject(s)
Antineoplastic Agents/therapeutic use , Lymphoma, Mantle-Cell/drug therapy , Phosphoinositide-3 Kinase Inhibitors , Purines/therapeutic use , Quinazolinones/therapeutic use , Aged , Aged, 80 and over , Antineoplastic Agents/pharmacology , Female , Humans , Lymphoma, Mantle-Cell/mortality , Lymphoma, Mantle-Cell/pathology , Male , Middle Aged , Purines/pharmacology , Quinazolinones/pharmacology , Recurrence , Risk Factors , Treatment Outcome
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