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1.
J Nanosci Nanotechnol ; 20(1): 155-160, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383150

RESUMO

Here we propose a wavelength-switchable erbium-doped fiber ring laser using a temperatureinsensitive spectral polarization-dependent loss (PDL) element and two fiber Bragg gratings (FBGs). The fiber PDL element was fabricated by inscribing a long-period grating (LPG) on polarizationmaintaining photonic crystal fiber (PMPCF) with a 10.6 µm CO2 laser. The LPG fabricated on PMPCF, referred to as PMPCF-LPG, has the characteristics of a fiber polarizer at two specific wavelengths due to the birefringence of PMPCF and the co-directional mode coupling of the LPG. The two wavelengths at which the fabricated PMPCF-LPG acts as a polarizer are two resonance wavelengths (~1528.58 and ~1555.90 nm) of the PMPCF-LPG, obtained for orthogonal input polarization states. By considering these two resonance wavelengths of the PMPCF-LPG, the Bragg wavelengths of two FBGs, which determine lasing wavelengths in our wavelength-switchable laser, were selected as ~1527.71 and ~1554.74 nm. As the temperature sensitivity of the PMPCF birefringence is 30 times lower than that of the birefringence of conventional polarization-maintaining fiber (PMF), the fabricated PMPCF-LPG could facilitate more stable switching operation between the two lasing wavelengths in comparison with a previous fiber laser employing an LPG inscribed on conventional PMF as a wavelength-switching filter. The lasing wavelengths of our laser could be switched by controlling input polarization of the PMPCF-LPG with a polarization controller, and temperature-insensitive wavelength switching operation was experimentally demonstrated over a temperature range of 25-100 °C.

2.
J Nanosci Nanotechnol ; 20(1): 257-262, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383164

RESUMO

Here we propose a novel optical fiber sensor capable of simultaneous measurement of strain and temperature by utilizing a long-period fiber grating (LPFG) inscribed on polarization-maintaining photonic crystal fiber (PMPCF) as a sensor head. The sensor head was fabricated by irradiating CO2 laser pulses to one side of PMPCF with line-by-line technique. The LPFG written on PMPCF (referred to as the PMPC-LPFG) exhibits two different wavelength-dependent loss bands, obtained at two orthogonal input polarization states. For two resonance wavelengths of these two wavelength-dependent loss bands, designated as Dips A and B, strain and temperature responses were investigated in a strain range of 0 to 2058 µÉ› with a step of 98 µÉ› and a temperature range of 30 to 85 °C with a step of 5 °C. Strain sensitivities of Dips A and B were measured and found to be approximately -0.82 and -1.43 pm/µÉ›, respectively, at room temperature (25 °C). Similarly, temperature sensitivities of Dips A and B were measured and found to be ~7.89 and ~4.76 pm/°C without applied strain (0 µÉ›), respectively. Owing to their linear and independent responses to strain and temperature, strain and temperature changes applied to the PMPC-LPFG can be simultaneously estimated from the measured wavelength shifts of the two resonance dips (Dips A and B) using their premeasured strain and temperature sensitivities. The experimental results prove that the PMPC-LPFG can be used as a sensor head for simultaneous measurement of strain and temperature.

3.
J Nanosci Nanotechnol ; 20(1): 285-292, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383168

RESUMO

Here we report on the simultaneous measurement of bending and temperature, carried out using a long-period fiber grating (LPFG) inscribed on polarization-maintaining fiber (PMF) with a CO2 laser at ~10.6 µm. An LPFG written on PMF, referred to as a PM-LPFG, has an input-polarizationdependent resonance dip, and two separated resonance dips, designated as Dips A and B, are obtained with respect to orthogonal input polarization. At the resonance wavelengths of Dips A and B, the core mode is coupled into two different cladding modes that have different bending and temperature sensitivities. The fabricated PM-LPFG whose grating period and length are ~505 µm and ~14.65 mm, respectively, has two resonance wavelengths, i.e., λA= ~1479.98 nm and λB = ~1568.78 nm, measured with respect to two orthogonal input polarization states. The bending sensitivities of this PM-LPFG were measured as ~22.23 and ~33.38 nm/m-1 (adjusted R² values: ~0.9916 and ~0.9810) at λA and λB, respectively, in a curvature range of 1.41-2.30 m-1. The temperature sensitivities of the PM-LPFG were measured as ~0.132 and ~0.039 nm/°C (adjusted R² values: ~0.9929 and ~0.9980) at λA and λB, respectively, in a temperature range of 30-90 °C. These linear bending and temperature responses of the PM-LPFG at two different resonance wavelengths enable simultaneous measurement of bending and temperature variations applied to the PM-LPFG.

4.
J Nanosci Nanotechnol ; 20(1): 344-350, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383177

RESUMO

In this paper, we propose a wavelength-tunable narrowband fiber multiwavelength filter based on polarization-diversified loop structure. The proposed filter consists of a polarization beam splitter, three half-wave plates (HWPs), two quarter-wave plates (QWPs) and two polarization-maintaining fiber (PMF) segments. The lengths of the two PMF segments are equal with each other. Among the five waveplates within the filter, a pair of an HWP and a QWP and the other pair of an HWP and a QWP are located in front of each PMF segment. The last HWP is placed after the second PMF and used to adjust the effective azimuthal angle of the second PMF. Azimuthal angle sets of the five waveplates, which can give additional phase shifts from 0 to 360° to the narrowband transmittance function derived from the Jones matrix formula, were theoretically found. Narrowband transmission spectra were calculated at eight waveplate angle sets selected among the angle sets derived above, which were designated as sets I, II, III, IV, V, VI, VII, and VIII that induced additional phase shifts from 0 to 315° (step: 45°) in the transmittance function. The calculated multiwavelength spectra clearly show that the narrowband multiwavelength spectrum can be wavelength-tuned by 0.1 nm as the waveplate angle set switches from set I to set VIII. This theoretical prediction was experimentally verified by appropriately controlling the azimuthal angle of each waveplate.

5.
J Nanosci Nanotechnol ; 20(1): 351-358, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383178

RESUMO

Here we report bidirectional current triggering (BCT) with a high repetition rate, achieved in a twoterminal planar device based on a vanadium dioxide (VO2) thin film by using a laser diode with a center wavelength of 976 nm as an excitation source. The VO2 thin film was grown on a sapphire (Al2O3) substrate using a pulsed laser deposition method, and the two-terminal planar device was fabricated by sawing the grown film into microscale unit devices, each of which was then attached onto a printed circuit board. Current triggering was performed by controlling the output power of the laser beam incident on the device surface. The proposed device allows stable current triggering operation even with laser pulses of higher repetition rate and lower energy because it is designed to have low heat capacity and thermal conductivity. Experimental results showed that a BCT of up to 30 mA was achieved at the maximum repetition rate of 8.0 Hz. The switching contrast between off- and on-state currents was calculated to be ~7295, and average rising and falling times of the current triggering were measured to be ~18.3 and ~22.5 ms, respectively.

6.
J Nanosci Nanotechnol ; 20(1): 420-426, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383188

RESUMO

Bidirectional current gating was realized in a vanadium dioxide (VO2) thin film-based two-terminal heterostructure device using a near-infrared laser diode (LD) with a center wavelength of 976 nm. The VO2 thin film used in the device fabrication was grown through pulsed laser deposition on a Si substrate with an aluminum nitride (AIN) buffer layer. The phase transition temperature of the fabricated VO2/AIN/Si heterostructure device was ~78 °C, which is higher by ~10 °C than that of the device based on a conventional VO2 thin film grown on a sapphire (Al2O3) substrate. Bidirectional current gating up to 60 mA was realized by directly irradiating the exposed thin film surface with the focused laser beam. The transient responses of the current flowing through the device were investigated for various pulse widths and repetition rates of the focused laser beam. The average switching contrast between off- and on-states was measured as ~9993. The average rise time of the current gating was ~31.5 ms with a much shorter fall time of ~4.0 ms. Our VO2/AIN/Si heterostructure device could provide a high on-state current and fast response due to a smaller device dimension and higher phase transition temperature compared with previous implementations.

7.
J Nanosci Nanotechnol ; 20(1): 478-484, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383196

RESUMO

In this paper, we propose an optical comb filter based on a polarization-diversity loop structure, whose two transmission channel spacings (TCS's) can be alternately switched between two principal axes of the filter by controlling waveplates contained in the filter. The proposed filter consists of a polarization beam splitter (PBS), three half-wave plates (HWPs), one Faraday rotator (FR), and two polarization-maintaining fiber (PMF) segments with different lengths (L and 2L) and equal birefringence (B). As the PMF segments are utilized as birefringence elements, the TCS of the filter is determined by the product of their effective length Le and birefringence B. For an input signal introduced into each principal axis of the filter, Le can be the sum of or difference between the two lengths (L and 2L) of the two PMF segments, that is, L or 3L, resulting in a TCS of S1 or S2, respectively, according to angular combination of the orientation angles of the three HWPs. At a specific set of the three HWP angles, the proposed filter can create two sinusoidal transmittance functions with different TCS's (S1 and S2) at the two principal axes, respectively. Also, the two TCS's (S1 and S2) are switchable with each other depending on three HWP angles for each principal axis. With the fabricated filter, the flexible switching between S1 and S2 could be successfully implemented for two orthogonally polarized input signals aligned along the two principal axes of the filter by properly controlling the three HWPs, without any modification of the filter configuration.

8.
Nat Commun ; 10(1): 3920, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477696

RESUMO

Ribo-T is a ribosome with covalently tethered subunits where core 16S and 23S ribosomal RNAs form a single chimeric molecule. Ribo-T makes possible a functionally orthogonal ribosome-mRNA system in cells. Unfortunately, use of Ribo-T has been limited because of low activity of its original version. Here, to overcome this limitation, we use an evolutionary approach to select new tether designs that are capable of supporting faster cell growth and increased protein expression. Further, we evolve new orthogonal Ribo-T/mRNA pairs that function in parallel with, but independent of, natural ribosomes and mRNAs, increasing the efficiency of orthogonal protein expression. The Ribo-T with optimized designs is able to synthesize a diverse set of proteins, and can also incorporate multiple non-canonical amino acids into synthesized polypeptides. The enhanced Ribo-T designs should be useful for exploring poorly understood functions of the ribosome and engineering ribosomes with altered catalytic properties.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31480131

RESUMO

Objectives: The aim of this study was to identify a distribution pattern of meat quality grade as a function of carcass yield index and the gender of Hanwoo (bull, cow, and steer) to determine the optimum point between both yield and quality. We also attempted to identify how pre- and post-deboning variables affect the gender-specific beef quality of Hanwoo. Methods: A total of 361 deboning variables, consisting of 7 pre-deboning and 24 post-deboning variables from bulls (n = 139), cows (n = 69), and steers (n = 153), were obtained from the National Institute of Animal Science (NIAS) in South Korea. The database was reconstructed to be suitable for a statistical significance test between the carcass yield index (CYI) and the meat quality grade (MQG) as well as classification of meat quality. Discriminant function analysis was used for classifying MQG using the deboning parameters of Hanwoo by gender. Results: The means of CYI according to 1+, 1, 2, and 3 of MQG were 68.64 2.02, 68.85 1.94, 68.62 5.88, and 70.99 3.32, respectively. High carcass yield correlated with low-quality grade, while high-quality meat most frequently was obtained from steers. The classification ability of pre-deboning parameters was higher than that of post-deboning parameters. Moisture and the shear force were the common significant parameters in all discriminant functions having a classification accuracy of 80.6%, 71%, and 56.9% for the bull, cow, and steer, respectively. Conclusion: This study provides basic information for predicting the meat quality by gender using pre-deboning variables consistent with the actual grading index.

11.
Arch Pharm Res ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31482490

RESUMO

In this study, we investigated the synergistic effect of L-buthionine sulfoximine (BSO) on the chlorin e6 (Ce6)-based photodynamic therapy (PDT) of cancer cells. Among various cancer cells, HCT116 cells have highest intracellular L-glutathione (GSH) level and SNU478 cells showed the lowest GSH level. BSO alone showed negligible intrinsic cytotoxicity against CCD986sk cells. Since HCT116 and SNU478 cells showed the highest and the lowest intracellular GSH levels, respectively, those were used to test synergistic effect on the Ce6-based PDT. In the absence of light, BSO and Ce6 combination did not practically increase reactive oxygen species (ROS) in either of HCT116 or SNU478 cells, while light irradiation increased ROS level dose-dependently. 10 µM BSO treatment significantly depleted total GSH level in cancer cells, i.e. total GSH level decreased to one-fourth of the control in HCT116 cells while it decreased to two-fifth of the control treatment at SNU478 cell. BSO showed synergistic effect on the ROS production in HCT116 cells while it has practically no benefits in ROS production of SNU478 cells. No synergistic effect was observed in viability of SNU478 cells because BSO itself was cytotoxic to SNU478 cells. However, BSO had negligible cytotoxicity against HCT116 cells and showed synergistic anticancer effect in combination with Ce6-based PDT. Furthermore, the addition of glutathione reduced ethyl ester (GSH-OEt), recovered intracellular GSH level, and cell viability with reduced the intracellular ROS level. We suggest that synergistic effect of BSO in the Ce6-based PDT should be considered with intrinsic intracellular GSH level of cancer cells.

12.
Nat Commun ; 10(1): 4019, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488820

RESUMO

Biological cellular structures have inspired many scientific disciplines to design synthetic structures that can mimic their functions. Here, we closely emulate biological cellular structures in a rationally designed synthetic multicellular hybrid ion pump, composed of hydrogen-bonded [EMIM+][TFSI-] ion pairs on the surface of silica microstructures (artificial mechanoreceptor cells) embedded into thermoplastic polyurethane elastomeric matrix (artificial extracellular matrix), to fabricate ionic mechanoreceptor skins. Ionic mechanoreceptors engage in hydrogen bond-triggered reversible pumping of ions under external stimulus. Our ionic mechanoreceptor skin is ultrasensitive (48.1-5.77 kPa-1) over a wide spectrum of pressures (0-135 kPa) at an ultra-low voltage (1 mV) and demonstrates the ability to surpass pressure-sensing capabilities of various natural skin mechanoreceptors (i.e., Merkel cells, Meissner's corpuscles, Pacinian corpuscles). We demonstrate a wearable drone microcontroller by integrating our ionic skin sensor array and flexible printed circuit board, which can control directions and speed simultaneously and selectively in aerial drone flight.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31490415

RESUMO

OBJECTIVES: Hepatocellular carcinoma can develop after hepatitis C virus eradication. We developed a new hepatocellular carcinoma risk score (HCC-SVR score) based on independent predictors for chronic hepatitis C after sustained virological response. METHODS: Between 2003 and 2016, a total of 1193 patients with chronic hepatitis C who achieved sustained virological response through antiviral therapy were included (669 for training cohort and 524 for validation cohort). The HCC-SVR score was developed using multivariate Cox proportional hazards regression modelling. RESULTS: Hepatocellular carcinoma (n = 19) occurred more frequently in older, male patients and was associated with liver cirrhosis; hypertension; diabetes; lower platelet count; higher alpha-fetoprotein, aspartate, and alanine aminotransferase; lower total cholesterol; and higher fibrosis-4 index (FIB-4) (all P < 0.05). FIB-4 (hazard ratio = 1.080), male gender (hazard ratio = 8.189), and higher alpha-fetoprotein (hazard ratio = 1.060) independently predicted hepatocellular carcinoma (all P < 0.05). HCC-SVR score successfully predicted hepatocellular carcinoma development risk [area under receiver operating characteristic curve (AUC) = 0.771, 0.857, and 0.911 at 2, 4, and 6 years, respectively]. The cumulative incidence rate of hepatocellular carcinoma differed significantly among groups stratified by HCC-SVR risk score (0-2 points, low; 3-7 points, intermediate; 8-9 points, high risk) (all P < 0.05 by log-rank test). HCC-SVR score was maintained in a validation cohort (n = 524) (AUC = 0.728 at 2 years, 0.737 at 4 years, and 0.809 at 6 years). CONCLUSION: The HCC-SVR score enables risk stratification for hepatocellular carcinoma development at sustained virological response in patients with chronic hepatitis C.

14.
Medicine (Baltimore) ; 98(37): e17090, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31517831

RESUMO

The decision as to whether patients should be admitted to a medical intensive care unit (ICU), in the absence of information concerning survival rates or prognostic factors in survival, is often challenging. We analyzed survival trends in relation to hospital discharge and examined patient and hospital characteristics associated with survival following ICU care, using a sample of nationwide claims data in Korea from 2002 through 2013. The Korean government implements a compulsory social insurance program that covers the country's entire population, and the Korean National Health Insurance Service-National Sample Cohort (NHIS-NSC) data from 2002 based on this program were used for this study. The NHIS-NSC is a stratified random sample of 1,025,340 subjects selected from around 46 million Koreans. We evaluated annual survival trends using the Kaplan-Meier test. Analyses of the relationship between survival and patient and hospital characteristics were performed using Cox regression analyses. Employing a multivariate model, variables were selected using the forward selection method to consider the multicollinearity of variables. A total of 32,553 patients admitted to an ICU between 2002 and 2013 were identified among the eligible beneficiaries. The number of patients who had histories of ICU admission steadily increased throughout the study period, and patients older than 80 years constituted a progressively increasing proportion of ICU admissions, from 7.3% in 2002 to 16.9% in 2007 to 23.1% in 2013. The mean number of mechanical equipment items applied consistently increased, while no difference was observed in the trend for overall 1-year survival in patients following ICU treatment across the study period: the 1-year survival rate ranged from 66.7% (year 2003) to 64.2% (year 2010). Advanced age, cancer, renal failure, pneumonia, and influenza were all associated with heightened risk of mortality within 1 year. Our results should prove useful to older patients and their clinicians in their decisions regarding whether to seek ICU care, with the goals of improving the end-of life care and optimizing resource utilization.

15.
J Dig Dis ; 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31509651

RESUMO

OBJECTIVES: Esophageal stricture after endoscopic submucosal dissection (ESD) is a significant complication impairing the quality of life. We investigated the efficacy of prophylactic steroid administration compared with that of oral steroid and intralesional steroid injection in preventing esophageal post ESD stricture and analyzed risk factors for stricture. METHODS: Patients who underwent ESD for superficial esophageal neoplasms with mucosal defect >75% of the circumference between January 2011 and August 2016 were eligible. Stricture was defined as the inability or resistance to pass a conventional endoscope. RESULTS: Of the 53 patients included, 25 were administered 30 mg of oral steroid 3 days after ESD, and the dose was gradually tapered through 8 weeks. Six patients underwent a single session of intralesional steroid injection immediately after ESD. The stricture rate was 50.0% in the ESD-alone group, 20% in the oral steroid group, and 33.3% in the steroid injection group. The oral steroid and steroid injection groups showed a significantly lower stricture rate than the ESD-alone group (22.6% vs. 50.0%, p = 0.046). The oral steroid group showed a significantly lower stricture rate than the ESD-alone group (p = 0.037). Multivariate analysis revealed that the extent of circumferential defect (Odd ratio [OR] = 13.015; 95% confidence interval [CI], 2.257 -76.077; p = 0.004), administration of steroid (OR, 0.108; 95% CI, 0.020-0.578; p = 0.009), specifically oral steroid (OR, 0.109; 95% CI, 0.019-0.622; p = 0.013) were significantly associated with post-ESD stricture. CONCLUSION: Oral steroid prophylaxis appeared to be a safe and effective treatment in preventing post-ESD stricture and improving patients' quality of life. This article is protected by copyright. All rights reserved.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31472087

RESUMO

OBJECTIVES: The aim of this randomized, controlled, parallel-arm study was to evaluate the (a) radiographic bone dimensional changes, (b) postoperative discomfort, and (c) early soft tissue wound healing outcomes, following extraction of maxillary anterior teeth (central and lateral incisors) and treatment with alveolar ridge preservation (ARP) with and without the adjunctive use of enamel matrix derivative (EMD). METHODS: Thirty extraction sockets were randomly assigned to two groups: deproteinized bovine bone mineral with 10% collagen covered with collagen membrane with the adjunctive use of EMD (test group) and without EMD (control group). Bone dimensional changes were measured using cone beam computed tomography at 3 and 5 months after ARP. The severity and duration of pain and swelling were evaluated using self-reported questionnaires, and soft tissue wound healing outcomes were assessed clinically. Chi-square tests and t tests were conducted to compare differences between the two groups. RESULTS: Radiographic and clinical analyses showed no significant differences in horizontal and vertical bone dimensional changes and soft tissue wound healing outcomes (including spontaneous bleeding, persistent swelling, and ulceration) between the two groups. There were no significant differences in the severity of pain and swelling between the two groups, but the durations of pain (difference [df] = 1.20, 95% CI = 0.33-2.06; p = .008) and swelling (df = 1.06, 95% CI = 0.11-2.01; p = .029) were significantly reduced in the test group. CONCLUSION: Alveolar ridge preservation with the adjunctive use of EMD reduced the durations of postoperative pain and swelling following maxillary anterior teeth extraction.

17.
Dig Dis Sci ; 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31367879

RESUMO

BACKGROUND/AIMS: Spontaneous retrograde migration of nasoenteral feeding tubes is common in clinical practice. The aim of the present study was to evaluate the effectiveness of nasoenteral feeding tube tip fixation with hemoclips to prevent tube dislodgement. METHODS: We retrospectively reviewed patients who underwent insertion of an endoscopic nasoenteral feeding tube with or without tube tip fixation with hemoclips at the Asan Medical Center in Korea from January 2016 to December 2017. We compared the incidence of tube dislodgment and procedure-related complications between the two groups. RESULTS: Of the total 225 procedures, 72 were performed using the clip-assisted method, while 153 were performed using the standard non-clip-assisted method. Tube dislodgement occurred in two (2.8%) cases in the clipping group and in 26 (17.0%) in the non-clipping group (p = 0.003). Non-clipping group had a sevenfold higher risk of tube dislodgement compared to clipping group after adjustments in multivariable logistic regression (adjusted OR 7.97, 95% CI 1.82-35.00). The procedure time was not significantly different between the two groups (17.6 ± 8.5 min in the clipping group vs. 17.8 ± 9.4 min in the non-clipping group, p = 0.872). In addition, procedure-related complications, such as bleeding, aspiration pneumonia, Mallory-Weiss tear, ileus, and tube obstruction, were not different between the two groups. Achieving target calorie intake took 10.4 ± 10.5 days in the clipping group and 7.9 ± 7.9 days in the non-clipping group (p = 0.293). CONCLUSION: Clip-assisted fixation of nasoenteral feeding tube was effective in preventing tube dislodgement.

18.
PLoS One ; 14(8): e0221650, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31442293

RESUMO

Several reports indicate crosstalk between the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) and estrogen, which has a protective effect in colorectal cancer (CRC). The aim of this study was to investigate the role of Nrf2 signaling in the anti-inflammatory effect of estrogen using Nrf2 knockout (Nrf2 KO) mouse embryonic fibroblasts (MEFs), a powerful system to test the function of target genes due to their easy accessibility, and rapid growth rates. After inducing inflammation by tumor necrosis factor alpha (TNF-α), the effects of 17ß-estradiol (E2) on the expression of proinflammatory mediators [i.e., NF-κB and inducible nitric oxide synthase (iNOS)] and estrogen receptors were evaluated by Western blot. In wild type (WT) MEFs, E2 treatment ameliorated TNF-α-induced nuclear translocation of NF-κB and expression of its target protein iNOS. Estrogen receptor beta (ERß) expression was decreased by TNF-α-induced inflammation and restored by E2 treatment. When treated to WT MEFs, E2 induced nuclear translocation of Nrf2. The inhibitory effect of E2 on TNF-α-induced enhancement of iNOS was markedly dampened in Nrf2 KO MEFs. Notably, ERß expression was significantly diminished in Nrf2 KO MEFs compared to that in WT cells. Promoter Database (EPD) revealed two putative anti-oxidant response elements (AREs) within the mouse ERß promoter. Furthermore, in WT MEFs, E2 treatment repressed TNF-α-induced expression of iNOS protein and recovered by 4-(2-phenyl-5,7-bis(trifluoromethyl)pyrazolo(1,5-a)pyrimidin-3-yl)phenol (PHTPP), a selective ERß antagonist, treatment, but not in Nrf2 KO MEFs. In conclusion, Nrf2 plays a pivotal role in the anti-inflammatory of estrogen by direct regulating the expression of ERß.

19.
Prehosp Emerg Care ; : 1-10, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31368831

RESUMO

Objective: We evaluated the validity of a newly developed mobile application (i.e. the Weighing Cam) for pediatric weight estimation compared with that of the Broselow tape. Methods: We developed an application that estimates the weight of pediatric patients using a smartphone camera and displays the drug dosage, device size, and defibrillation energy on the screen of the smartphone. We enrolled a convenience sample of pediatric patients aged <16 years who presented at two pediatric emergency departments of two tertiary academic hospitals in South Korea. The pediatric patients' heights and weights were measured; then, one researcher estimated the weights using the application. Using the measured height, we determined the weight estimated by the Broselow tape. We compared the estimated measurements by determining the mean percentage error (MPE), mean absolute percentage error, root mean square percentage error, and percentages predicted within 10% and 20% of the actual. Results: In total, 480 patients were enrolled in 16 age categories, each with 15 males and 15 females of different ages. The Weighing Cam demonstrated a lower bias (mean difference: -1.98% [95% confidence interval -2.91% to -1.05%] for MPE) and a higher proportion of estimated weights within 10% of the actual weights than the Broselow tape (mean difference: 9.1% [95% confidence interval 3.0% to 15.1%]). The Weighing Cam showed better performance in terms of accuracy and precision than the Broselow tape in all subgroups stratified by age or body mass index percentile. Conclusions: The Weighing Cam may estimate pediatric patients' weights more accurately than the Broselow tape. The Weighing Cam may be useful for pediatric resuscitation in both prehospital and hospital settings.

20.
PLoS One ; 14(8): e0220813, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31408477

RESUMO

Over the last few decades, the Internet has experienced tremendous growth in data traffic. This continuous growth due to the increase in the number of connected devices and platforms has dramatically boosted content consumption. However, retrieving content from the servers of Content Providers (CPs) can increase network traffic and incur high network delay and congestion. To address these challenges, we propose a joint deep learning and auction-based approach for congestion-aware caching in Named Data Networking (NDN), which aims to prevent congestion and minimize the content downloading delays. First, using recorded network traffic data on the Internet Service Provider (ISP) network, we propose a deep learning model to predict future traffic over transit links. Second, to prevent congestion and avoid high latency on transit links, which may experience congestion in the future; we propose a caching model that helps the ISP to cache content that has a high predicted future demand. Paid-content requires payment to be downloaded and cached. Therefore, we propose an auction mechanism to obtain paid-content at an optimal price. The simulation results show that our proposal prevents congestion and increases the profits of both ISPs and CPs.

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