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1.
Environ Health ; 23(1): 3, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38169380

RESUMEN

BACKGROUND: Air pollution can cause various respiratory and neurological diseases and continuous exposure can lead to death. Previous studies have reported that particulate matter (PM) exposure increases the risk of depression, suicidal thoughts, and suicidal death; however, the results are inconsistent and limited. This study aimed to examine the relationship between short-term PM exposure and suicide deaths, as well as investigate the short-term effects of PM on suicide death within vulnerable groups based on factors such as sex, age group, suicide-related information (note, method, and cause), psychiatric disorders, and physical diseases. METHODS: Data on a total of 28,670 suicide deaths from 2013 to 2017, provided by the Korea Foundation for Suicide Prevention, were analyzed. The study design employed a time-series analysis with a two-stage approach. In the first step, a generalized additive model combined with a distributed lag nonlinear model was used to estimate the short-term effect of PM exposure on suicide risk specific to each city. In the second step, the estimated results from each city were pooled through a meta-analysis to derive the overall effect. We determined the effects of single lag, cumulative lag, and moving average PM concentrations from days 0-7 before suicide. RESULTS: We confirmed an association between exposure to PM10 (≤ 10 µm in diameter) and deaths due to suicide. In particular, among individuals with psychiatric disorders and those who employed non-violent suicide methods, increased exposure to PM10 was associated with a higher risk of death by suicide, with percentage changes of 5.92 (95% confidence interval [CI]: 3.95-7.92) and 11.47 (95% CI: 7.95-15.11), respectively. Furthermore, in the group with psychiatric disorders, there was an observed tendency of increasing suicide risk as PM10 levels increased up to 120 µg/m3, whereas in the group with non-violent suicide deaths, there was a pronounced trend of rapid increase in suicide risk with an increase in PM10 up to 100 µg/m3. CONCLUSIONS: These results show an association between short-term exposure to PM and suicide. Our study adds evidence for the benefits of reducing PM in preventing diseases and improving mental health.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Suicidio , Humanos , Material Particulado/efectos adversos , Material Particulado/análisis , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Susceptibilidad a Enfermedades , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisis , China
2.
Opt Lett ; 44(19): 4881-4884, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31568466

RESUMEN

A laser supercontinuum is generated by cross-phase modulation (XPM) driven by an intense terahertz (THz) field in organic crystal OHQ-N2S. In this highly nonlinear medium, the THz electric field induces a time-varying optical phase modulation, which causes a spectacular spectral broadening and shifting of a co-propagating near-infrared laser pulse. The effect is enabled by the large electro-optic coefficient, the low absorption, and the good velocity matching between the laser and the THz pulse over the OHQ-N2S crystal thickness. The XPM occurs when the THz field is aligned along the polar axis of the OHQ-N2S. The results display a promising pathway for ultrafast control of the spectral and temporal properties of laser pulses using THz stimuli.

3.
Opt Express ; 26(23): 30786-30794, 2018 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-30469972

RESUMEN

We report on generation of strong and broadband terahertz (THz) pulses via collinearly phase-matched optical rectification of near-infrared femtosecond pulses in the organic nonlinear optical HMB-TMS (2-(4-hydroxy-3-methoxystyryl)-3-methylbenzo[d]thiazol-3-ium 2,4,6-trimethylbenzenesulfonate) single crystals which exhibit optimal molecular orientation and large macroscopic optical nonlinearity for efficient THz wave generation. Single-cycle THz pulses with a peak electric field strength of 0.66 MV/cm and a bandwidth from 0.1 to 5.4 THz are achieved from an HMB-TMS crystal with only a 2-mm clear aperture pumped by 1350 nm pulses at moderate fluences. The generated THz energy is about 1 µJ and the corresponding pump-to-THz energy conversion efficiency reaches 0.23%.

4.
Nano Lett ; 16(10): 6078-6085, 2016 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-27657176

RESUMEN

A phase change nanowire holds a promise for nonvolatile memory applications, but its transition mechanism has remained unclear due to the analytical difficulties at atomic resolution. Here we obtain a deeper understanding on the phase transition of a single crystalline Ge2Sb2Te5 nanowire (GST NW) using atomic scale imaging, diffraction, and chemical analysis. Our cross-sectional analysis has shown that the as-grown hexagonal close-packed structure of the single crystal GST NW transforms to a metastable face-centered cubic structure due to the atomic migration to the pre-existing vacancy layers in the hcp structure going through iterative electrical switching. We call this crystal structure transformation "metastabilization", which is also confirmed by the increase of set-resistance during the switching operation. For the set to reset transition between crystalline and amorphous phases, high-resolution imaging indicates that the longitudinal center of the nanowire mainly undergoes phase transition. According to the atomic scale analysis of the GST NW after repeated electrical switching, partial crystallites are distributed around the core-centered amorphous region of the nanowire where atomic migration is mainly induced, thus potentially leading to low power electrical switching. These results provide a novel understanding of phase change nanowires, and can be applied to enhance the design of nanowire phase change memory devices for improved electrical performance.

5.
Prog Transplant ; 26(4): 394-396, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27555077

RESUMEN

The use of a human leukocyte antigen (HLA) homozygous donor to a haploidentical recipient is a well-documented cause of transfusion-associated graft-versus-host disease (GVHD). Several authors have reported that use of a graft from an HLA-homozygous donor with 1-way donor-recipient HLA matching led to an extremely high risk of developing GVHD in LDLT. We have experienced a fatal case of acute GVHD following adult-to-adult LDLT from a donor who was heterozygous at a single HLA locus. A 53-year-old female underwent LDLT for chronic hepatitis B and recurrent hepatocellular carcinoma. The donor was her 23-year-old son. The HLA phenotype of the donor was not homozygous (A24, -; B54, -; DR4, 9) and revealed one-way donor-dominant HLA matching at two loci with the recipient (A2, 24; B48, 54; DR4, 12). On the fortieth postoperative day, the patient showed erythematous skin lesions. Skin biopsy revealed typical findings of GVHD. Donor-derived chimerism was demonstrated by performing fluorescent in situ hybridization (FISH) using the recipient's skin tissue. As the clinical course deteriorated, etanercept was started in addition to broad-spectrum antibiotics but there was no improvement. As multi-organ failure progressed, the patient succumbed to death on the 54th postoperative day, which was 2 weeks after onset of GVHD. The prevention of GVHD is more important since the results of treatment have been disappointing. We have experienced a fatal case of acute GVHD following adult-to-adult LDLT from a HLA non-homozygous donor. HLA heterozygosity at a single locus does not preclude the possibility of developing GVHD following adult-to-adult LDLT.


Asunto(s)
Enfermedad Injerto contra Huésped , Antígenos HLA , Trasplante de Hígado , Donadores Vivos , Adulto , Resultado Fatal , Femenino , Prueba de Histocompatibilidad , Humanos , Hibridación Fluorescente in Situ , Neoplasias Hepáticas/cirugía , Persona de Mediana Edad
6.
Nanotechnology ; 25(14): 145604, 2014 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-24633210

RESUMEN

Hexagonal boron nitride (h-BN) has gained great attention as a two-dimensional material, along with graphene. In this work, high-quality h-BN monolayers were grown in wafer scale (7 × 7 cm(2)) on Cu substrates by using low-pressure chemical vapor deposition (LPCVD). We created h-BN monolayers that were free of polymeric aminoborane (BH2NH2) nanoparticles, which are undesirable by-products of the ammonia borane precursor, by employing a simple filtering system in the CVD process. The optical band gap of 6.06 eV and sharp and symmetric Raman peak measured at 1371 cm(-1) indicate the synthesis of monolayer h-BN. In addition, spherical aberration (CS)-corrected high-resolution transmission electron microscopic images confirm the production of a single-layer hexagonal array of boron and nitrogen atoms.

7.
Am J Kidney Dis ; 61(6): 899-909, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23540260

RESUMEN

BACKGROUND: α-Klotho is reported to have protective effects against kidney injury, and its renal expression is decreased in many experimental models of kidney disease. However, circulating α-klotho levels in human chronic kidney disease (CKD) and the relationship to progression are unknown. STUDY DESIGN: Post hoc analysis of a prospective cohort study. SETTING & PARTICIPANTS: 243 of 301 participants from a CKD cohort at our institution between January 2006 and December 2011 were eligible for the study. PREDICTOR: Baseline α-klotho levels. OUTCOMES: Primary outcome was the composite of doubling of baseline serum creatinine concentration, end-stage renal disease, or death. End-stage renal disease was defined as onset of treatment by renal replacement therapy. MEASUREMENTS: Serum α-klotho and fibroblast growth factor 23 (FGF-23) were measured using enzyme-linked immunosorbent assay. RESULTS: Lower serum α-klotho levels were associated with more severe CKD stage in the cross-sectional analysis of the baseline data (P for trend < 0.001). In the adjusted multivariable linear regression model, log(α-klotho) was associated independently with estimated glomerular filtration rate (ß = 0.154; P = 0.001). Cox regression analysis showed that baseline α-klotho level independently predicted the composite outcome after adjustment for age, diabetes, blood pressure, estimated glomerular filtration rate, proteinuria, parathyroid hormone level, and FGF-23 level (HR per 10-pg/mL increase, 0.96; 95% CI, 0.94-0.98; P < 0.001). When patients were categorized into 2 groups according to baseline median α-klotho value, 43 (35.2%) patients with α-klotho levels ≤396.3 pg/mL reached the primary composite outcome compared with 19 (15.7%) with α-klotho levels >396.3 pg/mL (HR, 2.03; 95% CI, 1.07-3.85; P = 0.03). LIMITATIONS: Uncontrolled dietary phosphorus intake and use of frozen samples. CONCLUSIONS: This observational study showed that low circulating α-klotho levels were associated with adverse kidney disease outcome, suggesting that α-klotho is a novel biomarker for CKD progression. More data from larger prospective longitudinal studies are required to validate our findings.


Asunto(s)
Glucuronidasa/sangre , Insuficiencia Renal Crónica/sangre , Adulto , Anciano , Biomarcadores/sangre , Estudios de Cohortes , Creatinina/sangre , Estudios Transversales , Progresión de la Enfermedad , Ensayo de Inmunoadsorción Enzimática , Femenino , Factor-23 de Crecimiento de Fibroblastos , Factores de Crecimiento de Fibroblastos/sangre , Tasa de Filtración Glomerular , Humanos , Fallo Renal Crónico/sangre , Proteínas Klotho , Modelos Lineales , Masculino , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Adulto Joven
8.
Artículo en Inglés | MEDLINE | ID: mdl-37569077

RESUMEN

This study aimed to evaluate the impact of parental mental health on adolescent offspring. Data regarding 6512 families from the 2010-2021 Korean National Health and Nutrition Examination Survey were analyzed; among them, 428 were placed in the suicidal ideation (SI) group and 421 were placed in the matched control (MC) group. This number was selected for the use of the propensity score matching method. The findings highlighted significant associations between parental mental health and adolescent suicidal ideation, with mothers in the SI group having higher odds of Diagnosed Depression (OR 2.109, 1.023-4.350 95% CI), Depressive Mood (OR 2.155, 1.224-3.793 95% CI), and Suicidal Ideation (OR 2.532, 1.322-4.851 95% CI) compared to the MC group. Regarding the fathers, paternal Suicidal Ideation (OR 4.295, 1.747-10.599 95% CI) was the only significant factor for adolescent suicidal ideation. In contrast, maternal depressive symptoms and help-seeking behavior significantly impacted adolescent help-seeking; Maternal Depressive Mood increased with adolescent Help-Seeking (OR 4.486, 1.312-15.340 95% CI) while Maternal Suicidal Ideation reduced the probability of Help-Seeking in the SI group (OR 0.15, 0.031-0.721, 95% CI). Chronic and severe depressive symptoms in mothers could make adolescents less likely to seek help for their suicidal ideations. Therefore, clinicians working with adolescents should prioritize a family-oriented approach.


Asunto(s)
Conducta de Búsqueda de Ayuda , Ideación Suicida , Masculino , Femenino , Humanos , Adolescente , Depresión/epidemiología , Depresión/psicología , Encuestas Nutricionales , Salud Mental , Madres/psicología
9.
Materials (Basel) ; 16(6)2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36984418

RESUMEN

Ladder-type polysilsesquioxanes (LPSQs) containing phenyl as a high refractive index unit and cyclic epoxy as a curable unit were found to be excellent candidates for a transparent color conversion layer for displays due to being miscible with organic solvents and amenable to transparent film formation. Therefore, the LPSQs were combined with luminescent lanthanide metals, europium Eu(III), and terbium Tb(III), to fabricate transparent films with various emission colors, including red, orange, yellow, and green. The high luminescence and transmittance properties of the LPSQs-lanthanide composite films after thermal curing were attributed to chelating properties of hydroxyl and polyether side chains of LPSQs to lanthanide ions, as well as a light sensitizing effect of phenyl side chains of the LPSQs. Furthermore, Fourier-transform infrared (FT-IR) and X-ray photoelectron spectroscopy and nanoindentation tests indicated that the addition of the nanoparticles to the LPSQs moderately enhanced the epoxy conversion rate and substantially improved the wear resistance, including hardness, adhesion, and insusceptibility to atmospheric corrosion in a saline environment. Thus, the achieved LPGSG-lanthanide hybrid organic-inorganic material could effectively serve as a color conversion layer for displays.

10.
J Clin Med ; 11(9)2022 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-35566453

RESUMEN

Hyperglycemia is among the main risk factors for severe COVID-19. We evaluated the association of glycated albumin (GA) and GA/HbA1c ratio with progression of COVID-19 from mild to severe disease in patients with type 2 diabetes mellitus (T2DM). Our retrospective study included 129 patients aged over 18 years with COVID-19 and T2DM who did not have any need of oxygen supplement. Of these, 59 patients whose COVID-19 was aggravated and required oxygen supplementation eventually were classified as having severe disease. Clinical and laboratory data were compared between mild and severe cases. The median of GA (18.4% vs. 20.95%, p = 0.0013) and GA/HbA1c (2.55 vs. 2.68, p = 0.0145) were higher in severe disease than in mild disease and positively correlated with C-reactive protein (Kendal Tau coefficient 0.200 and 0.126, respectively; all p < 0.05). Multiple logistic regression analysis showed that GA (odds ratio (OR), 1.151; 95% confidence interval (CI), 1.024−1.294) and GA/HbA1c (OR, 8.330; 95% CI, 1.786−38.842) increased the risk of severe disease. Patients with GA 20% or higher were 4.03 times more likely to progress from mild to severe disease. GA and GA/HbA1c ratio predicted progression of COVID-19 from mild to severe disease in patients with T2DM.

11.
Artículo en Inglés | MEDLINE | ID: mdl-34501559

RESUMEN

Long-term exposure to childhood abuse and occurrence of mental illness are positively correlated. Using long-term tracking data in Korea, we identified the characteristics of children and adolescents who experienced abuse and impact thereof on their psychopathology. Using the Korea Welfare Panel data, 354 teenagers in grades 4-6 of elementary school participated, were assessed at baseline, and monitored 3 years later. They were categorized into Never, Occurrence, Continuation, and Discontinuation groups according to changes in the abuse experienced. Psychopathology was evaluated using K-CBCL. Childhood abuse experience significantly affected psychopathology. At the baseline, the Continuation and Discontinuation groups had a higher severity of psychopathology than the Never group. Psychopathology at the baseline was associated with whether the patient experienced abuse that year. In the follow-up observation, the risk of psychopathology in the Occurrence and Continuation groups was higher than that in the Never group. The Discontinuation group had decreased psychopathology, which was not clinically significant in the follow-up observation (INT aRR = 2.09; 95% CI 0.61-7.13, EXT aRR = 4.23; 95% CI 1.12-16.07). Stopping abuse in late childhood reduces adolescents' psychopathology in the long term, meaning they can recover their normal developmental trajectory according to risk groups and provide effective interventions including discontinuation of abuse.


Asunto(s)
Maltrato a los Niños , Trastornos Mentales , Adolescente , Niño , Humanos , Estudios Longitudinales , Trastornos Mentales/epidemiología , Psicopatología , Factores de Riesgo
12.
Am J Transl Res ; 13(6): 5880-5891, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34306332

RESUMEN

BACKGROUND: Excessive postoperative portal pressure is associated with post-hepatectomy liver failure and small-for-size syndrome after partial liver transplantation. This study aimed to identify the portal modulation effects of terlipressin on liver regeneration and survival in a porcine model subjected to 90% hepatectomy. METHODS: Twenty pigs undergoing 90% hepatectomy were divided into control (n = 10) and terlipressin (n = 10) groups. Terlipressin 0.5 mg was injected subcutaneously three times a day, from immediately before hepatectomy to 7 days after surgery, for surviving pigs in the terlipressin group. Portal pressure measurement, biochemical analysis, assessment of molecular markers for liver regeneration, and immunohistochemistry were performed in both groups. RESULTS: The 7-day survival rate was significantly higher in the terlipressin group than that in the control group. Portal pressure in the terlipressin group was lower than that in the control group at 30 min and 1 h after hepatectomy. Total bilirubin level was lower in the terlipressin group than that in the control group at 1 h and 6 h after hepatectomy. Proliferating cell nuclear antigen expression was higher in the control group than that in the terlipressin group at 6 h after hepatectomy, while the proportion of Ki-67-positive cells was higher in the terlipressin group than that in the control group at 7 days after hepatectomy. Endothelin-1 level reflecting liver injury was lower in the terlipressin group than that in the control group at 1 h and 6 h after hepatectomy. CONCLUSION: Terlipressin could optimize liver regeneration and improve survival through rapid and effective portal modulation after extensive hepatectomy.

13.
Ann Hepatobiliary Pancreat Surg ; 23(2): 133-137, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31225414

RESUMEN

BACKGROUNDS/AIMS: Essential nutritional support and nutrition therapy for patients with hepatobiliary and pancreatic diseases undergoing surgery is critical, as it may improve clinical outcome. How to implement rational fluid therapy and nutritional support after surgery and effectively protect organ function is crucial for postoperative recovery. The aim this study was to examine the safety and efficacy of peripheral nutrition fluid (MG-TNA®) in patients undergoing surgery for hepatobiliary and pancreatic disease. METHODS: All adult patients undergoing surgery for hepatobiliary and pancreatic disease received peripheral nutrition fluid (MG-TNA®) on the second postoperative day for 3 days. During administration of parenteral nutrition, patients were closely monitored for adverse effects (primary endpoint). Secondary endpoints included nutritional parameters such as serum prealbumin, transferrin, and creatine kinase (CK) levels. RESULTS: Thirty patients completed the study and were included in the full analysis set. There was no evidence of metabolic complications such as hyperglycemia, azotemia, hypertriglyceridemia, metabolic acidosis and hypokalemia. In addition, there were no adverse effects. There was a significant decrease in serum prealbumin and CK on the third postoperative day (p<0.0001). Although not statistically significant, serum transferrin levels tended to decrease (p=0.0519). CONCLUSIONS: Administration of peripheral nutrition fluid (MG-TNA®) during postoperative period in patients undergoing surgery for hepatobiliary and pancreatic disease proved to be safe with improvement of the nutritional state of the patient.

14.
Adv Mater ; 30(3)2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29205541

RESUMEN

A highly stretchable and reliable, transparent and conductive entangled graphene mesh network (EGMN) exhibits an interconnected percolation network, as usually shown in 1D nanowires, but with the electrical, mechanical, and thermal properties of 2D graphene. The unique combination of the 2D material properties and the network structure of wrinkled, waved, and crumpled graphene enables the EGMN to demonstrate excellent electrical reliability, mechanical durability, and thermal stability, even under harsh environmental and external conditions such as very high temperature, humidity, bending, and stretching. Specifically, after 100 000 cycles of bending with radius of 2 mm, the EGMN maintains its resistance similar to its initial value. The EGMN shows a steady monotonic response in resistance to strain cycles of 50 000 times with nearly constant gauge factors of 0.76, 1.67, and 2.55 at 10%, 40%, and 70% strains, respectively. Moreover, the EGMN shows very little change in resistance with the temperature increasing up to 1000 °C, by in situ thermal analysis with transmission electron microscopy and also by long-term stability testing at 70 °C and 70% relative humidity for 30 d. These results demonstrate that this novel entangled graphene mesh network can significantly broaden the application areas for various types of wearable and stretchable devices.

15.
Artículo en Inglés | MEDLINE | ID: mdl-30581485

RESUMEN

Selaginella Herba is the dried, aerial part of Selaginella tamariscina (P.Beauv.) Spring and has been used to treat amenorrhea, abdominal pain, headaches, and hematuria in Korea. However, scientific evidence regarding the anti-inflammatory activity and action mechanism of Selaginella tamariscina is lacking. Thus, the present study was performed to investigate the anti-inflammatory and antioxidant activities of Selaginella tamariscina ethanol extract (STE) against lipopolysaccharide (LPS)-induced inflammatory responses and identify the molecular mechanism responsible. STE was prepared by heating in 70% ethanol and its quality was confirmed by HPLC. STE dose-dependently inhibited the productions of inflammatory mediators (NO and PGE2) and proinflammatory cytokines (IL-1ß and IL-6) in LPS-stimulated RAW 264.7 cells. STE markedly suppressed the phosphorylations of MAPKs, IκB-α, and NF-κB and the nuclear translocation of NF-κB induced by LPS stimulation. In addition, STE exhibited good free radical scavenging activity and prevented ROS generation by LPS. STE also upregulated the expression of Nrf2 and HO-1 and promoted the nuclear translocation of Nrf2. Taken together, STE was found to have anti-inflammatory and antioxidant effects on RAW 264.7 macrophages and the mechanism appeared to involve the MAPK, NF-κB, and Nrf2/HO-1 signaling pathways. These results suggest that STE might be useful for preventing or treating inflammatory diseases and provide scientific evidence that supports the developments of herbal prescriptions or novel natural products.

16.
Emerg Med Int ; 2018: 8701957, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30245884

RESUMEN

Due to an increase in traffic collisions, the demand for prehospital medical services is on the rise, even in low-resource countries where emergency ambulance services have not been previously provided. To build a sustainable and continuous prehospital ambulance operation model, it is necessary to consider the medical system and economic conditions of the corresponding country. In an attempt to construct a prehospital ambulance operation model that ensures continuous operation, a pilot "emergency patient transporting service from field to hospital" operation was established for approximately three months in Kinshasa, the capital of the DR Congo. To construct a continuously operating model even after the pilot operation, willingness to pay (WTP) by type of emergency medical and transport service was investigated by implementing the contingent valuation method (CVM). Using CVM, the WTP for prehospital emergency services targeting ambulance services personnel, patients, policemen, and hospital staff participating in the pilot operation was calculated. The results of the pilot operation revealed that there were a total of 212 patients with a mean patient number of 2.4 per day. A total of 155 patients used the services for hospital transport, while 121 patients used the services for traffic collisions. Traffic collisions were the category in which ambulance services were most frequently needed (66.2%). Pay services were most frequently utilized in the home-visit services category (40.9%). Based on these results, eight independently operated ambulance operation models and sixteen models that utilize hospital medical personnel and policemen already belonging to existing institutions were proposed. In an effort to implement emergency medical ambulance services in the DR Congo, medical staff receiving pay for performance (incentive pay) should be deployed in the field and on call. Accordingly, with respect to sustainable development goals, various pay-for-service models should be used.

17.
Phytomedicine ; 24: 24-30, 2017 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-28160858

RESUMEN

BACKGROUND: Despite the benefits from different options of therapy for breast cancer, resistance of the disease to these therapies is rising and a novel agent is needed. Erythro-austrobailignan-6 (EA6) exhibits anti-cancer activity. However, the detailed anti-tumor mechanisms by which EA6 inhibits 4T-1 and MCF-7 cell growth have not been well studied. PURPOSE: In this study, we investigated the anti-proliferative and anti-tumor properties of EA6 on breast carcinoma and its accompanying mechanisms. METHODS: The cytotoxic and apoptotic effect of EA6 were measured in breast cancer cell lines of 4T-1 and MCF-7. The role of EA6 on cell proliferation and migration was examined by immunoblotting. The anti-tumor activity of EA6 was assessed in mice inoculated with 4T-1 breast cancer cells. RESULTS: EA6 increased the number of Annexin V-positive apoptotic bodies and cleaved form of caspase-3 in a dose-dependent manner and phosphorylated JNK and p38 in both cells. Moreover, EA6 down-regulated cell cycle dependent proteins of CDK-4 and cyclin D1, and increased G0/G1 population in both cells. EA6-induced apoptosis is mediated by p38 MAPK and caspase-3 activation in both cells. EA6 significantly reduced HER2/EGFR/integrin ß3 expression and Src phosphorylation, which was dependent on p38 MAPK activation in 4T-1 and MCF-7 cells. Furthermore, we confirmed the down-regulation of topoisomerases by EA6 treatment, but the overall effects of EA6 on topoisomerase isotype were cell type specific. Finally, EA6 (20mg/kg/day) significantly reduced mammary tumor volume in 4T-1 bearing mice by down-regulating HER2/EGFR/integrin ß3 expression in tumor tissues. CONCLUSIONS: Our results offer a novel insight into the mechanism of EA6-induced apoptosis in breast cancer cells. We propose that EA6 treatment resulted in the activation of p38 MAPK and caspase-3, which eventually participated in regulating apoptosis in 4T-1 and MCF-7 cells.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Lignanos/uso terapéutico , Células MCF-7/efectos de los fármacos , Extractos Vegetales/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Línea Celular Tumoral/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Regulación hacia Abajo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Fitoterapia , Extractos Vegetales/uso terapéutico , Proteínas Quinasas p38 Activadas por Mitógenos/genética
18.
Adv Mater ; 29(30)2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28589627

RESUMEN

Highly efficient nonlinear optical organic crystals are very attractive for various photonic applications including terahertz (THz) wave generation. Up to now, only two classes of ionic crystals based on either pyridinium or quinolinium with extremely large macroscopic optical nonlinearity have been developed. This study reports on a new class of organic nonlinear optical crystals introducing electron-accepting benzothiazolium, which exhibit higher electron-withdrawing strength than pyridinium and quinolinium in benchmark crystals. The benzothiazolium crystals consisting of new acentric core HMB (2-(4-hydroxy-3-methoxystyryl)-3-methylbenzo[d]thiazol-3-ium) exhibit extremely large macroscopic optical nonlinearity with optimal molecular ordering for maximizing the diagonal second-order nonlinearity. HMB-based single crystals prepared by simple cleaving method satisfy all required crystal characteristics for intense THz wave generation such as large crystal size with parallel surfaces, moderate thickness and high optical quality with large optical transparency range (580-1620 nm). Optical rectification of 35 fs pulses at the technologically very important wavelength of 800 nm in 0.26 mm thick HMB crystal leads to one order of magnitude higher THz wave generation efficiency with remarkably broader bandwidth compared to standard inorganic 0.5 mm thick ZnTe crystal. Therefore, newly developed HMB crystals introducing benzothiazolium with extremely large macroscopic optical nonlinearity are very promising materials for intense broadband THz wave generation and other nonlinear optical applications.

19.
Int J Surg ; 31: 40-6, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27260310

RESUMEN

BACKGROUND: Anti-adhesive agents are increasingly used to reduce the incidence of postoperative adhesions following abdominal surgery. Bile leakage after liver resection remains a major cause of postoperative morbidity. The aim of this study was to examine the effect of anti-adhesive agent on bile leakage after liver resection. MATERIALS AND METHODS: 77 patients were enrolled to receive an anti-adhesive agent (study group) during liver resection between May 2012 and August 2013. The study group was compared to a match-paired control group. Clinical data were collected including bilirubin concentration in serum and drain fluid and bile leakage rate. In addition, a separate analysis was performed between patients with and without postoperative bile leakage. RESULTS: There was no difference in bile leakage rate or hospital stay between the study group (n = 77) and control group (n = 77). Of the total number of patients (n = 154), there were 29 patients with postoperative bile leak and 125 patients without bile leak. On univariate analysis, patients without history of hepatitis were significantly associated with bile leakage. In addition, liver resection with broader cut surface area was associated with bile leakage. Application of anti-adhesive agent was not associated with bile leakage. On multivariate analysis, resection with broader cut surface area (OR = 2.788, p = 0.026) and patients without history of hepatitis (OR = 5.153, p = 0.039) were significantly associated with bile leakage. CONCLUSIONS: Larger area of cut-surface and patients without history of hepatitis were significant risk factors for bile leakage. The use of anti-adhesive agent was not associated with increased risk of bile leakage.


Asunto(s)
Alginatos/administración & dosificación , Fuga Anastomótica/etiología , Hepatectomía/efectos adversos , Hepatopatías/cirugía , Poloxámero/administración & dosificación , Tensoactivos/administración & dosificación , Administración Tópica , Bilis , Femenino , Ácido Glucurónico/administración & dosificación , Ácidos Hexurónicos/administración & dosificación , Humanos , Incidencia , Hígado/efectos de los fármacos , Hígado/cirugía , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Adherencias Tisulares/etiología , Adherencias Tisulares/prevención & control
20.
J Ethnopharmacol ; 194: 733-739, 2016 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-27769945

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Evodiae Fructus (EF) is the dried, unripe fruit of Evodia rutaecarpa Benth., and one of the main components of traditional herbal prescriptions issued for the treatment of sterility caused by irregular menstruation in Korea. However, scientific evidence regarding the efficacy and action mechanism of EF is lacking. AIM OF THE STUDY: In this study, the authors established an in vitro screening tool to identify promising new drug candidates in herbal medicines for the prevention and treatment of premature ovarian failure. The protective effects of EF extracts against 4-vinylcyclohexene diepoxide (VCD)-induced ovotoxicity were investigated and the molecular mechanism responsible was sought. MATERIAL AND METHODS: EF extract was prepared by boiling EF in water and its quality was confirmed by high performance liquid chromatography. CHO-K1 (Chinese hamster ovary cells) and COV434 (human ovarian granulosa cells) cells were plated, pretreated with EF extract for 2h and then treated with 1.5mM or 0.5mM VCD for 24h, respectively. Cell viabilities were measured using an MTT assay, and protein levels were determined by western blotting. RESULTS: VCD significantly suppressed the viability of both CHO-K1 and COV434 cells in a dose-dependent manner and induced the apoptosis of CHO-K1 cells at 1.5mM. EF extract dose-dependently blocked the ovotoxicity induced by treatment with VCD. Furthermore, EF extract significantly activated Akt and downstream effectors such as mTOR and GSK-3ß in CHO-K1 cells. The ability of EF extract to prevent cytotoxicity by VCD was antagonized by pretreatment of LY294002, a PI3K/Akt inhibitor. CONCLUSION: EF has the ability to protect ovary cells against VCD-induced ovotoxicity, probably via Akt activation. These results suggest that the beneficial effects of EF might be useful for preventing premature ovarian failure or unexplained infertility caused by environmental factors.


Asunto(s)
Ciclohexenos/toxicidad , Activación Enzimática/efectos de los fármacos , Evodia/química , Células de la Granulosa/efectos de los fármacos , Ovario/efectos de los fármacos , Extractos Vegetales/farmacología , Sustancias Protectoras/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Compuestos de Vinilo/toxicidad , Animales , Apoptosis/efectos de los fármacos , Células CHO , Línea Celular , Cricetinae , Cricetulus , Femenino , Humanos
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