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1.
J Infect Chemother ; 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32631735

RESUMO

The assessment of the incubation period, which is the period between the infection and the illness onset, is essential to identify the sufficient isolation period for infectious diseases. In South Korea, a few cases of the coronavirus disease 2019 (COVID-19) were identified after the 14-day self-quarantine program, and the length of this quarantine has raised controversial issues for the Korean public health professionals. We estimated the COVID-19 incubation period using the log-normal distribution from publicly available data. The data were obtained from the press release of the Busan city department of public health and news reports. We collected and analysed information for 47 patients with a median age of 30. We estimated that the median incubation period was three days (95% Confidence Interval, 0.6-8.2). We also did not find any significant difference in the incubation period between males and females. Our findings indicate that a 14-day self-quarantine program should be sufficient to prevent spreading in the infection of suspected individuals with COVID-19 in the community.

2.
J Cosmet Dermatol ; 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32459880

RESUMO

BACKGROUND: Blue light from electronic devices enriched with a peak at 456 nm affects circadian rhythm and antioxidant balance of skin, necessitating the study of photoprotection against the 456-nm blue light. AIMS: This study aims to report that blue light (456 nm) can cause skin pigmentation and proposes a new clinical evaluation method for blue light (456 nm) protection based on the skin pigmentation level. PATIENTS/METHODS: We developed a clinical device (ABC deviceTM ) that emits blue light (peak = 456 nm). Based on the minimal persistent pigment darkening dose (MPPD) determined from visual evaluation and melanin index measurements, we proposed the "protection grade of blue light (PB)" guideline to assess the protective ability of skin against blue light. RESULTS: Human skin irradiated with blue light (456 nm) showed a light dose-dependent degree of pigmentation. The MPPD on unprotected and protected skin was 135 J/cm2 or 180 J/cm2 and 135-225 J/cm2 , respectively. The ABC device™ and the proposed clinical method were used to test the four blue light blocking assessments of TiO2 . Consequently, the inorganic filter with TiO2 effectively blocked the blue light (456 nm). The AP product demonstrated the ability to block blue light by 1.15 times (PB = 1.15), which significantly lowered the melanin index of the skin after irradiation as compared to that of the unprotected skin (P < .001). CONCLUSION: We propose an objective clinical evaluation method for blue light protection. This study elucidates the properties of blue light blockers for customers suffering from blue light pollution.

3.
Chemosphere ; 256: 127084, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32460158

RESUMO

Benzalkonium chloride (BKC) is a commonly used preservative in personal care products and pharmaceutical preparations. However, its ecological risks are not well understood because of lack of monitoring data and ecotoxicological information. In the present study, occurrence of BKC was investigated in the waters near a pharmaceutical manufacturing complex of South Korea and its acute and chronic ecotoxicities were evaluated using Daphnia magna and Japanese medaka (Oryzias latipes). Associated ecological risks were estimated by calculating hazard quotients (HQs). In addition, endocrine disruption potency of BKC was compared with those of other frequently used preservatives using human adrenal (H295R) and rat pituitary (GH3) cells. High concentration of BKC was detected at locations near the pharmaceutical manufacturing plants, i.e., 35.8 µg/L for dodecyl benzyl dimethyl ammonium chloride (BKC-C12), and 21.6 µg/L tetradecyl benzyl dimethyl ammonium chloride (BKC-C14). In Daphnia, 48 h immobilization EC50 and 21 d reproduction NOEC were determined at 41.1 µg/L and ≥10.8 µg/L, respectively. For O. latipes, 96 h LC50 was determined at 246 µg/L while the growth inhibition NOEC was ≥113.4 µg/L following early life stage exposure. BKC significantly up-regulated vitellogenin gene of juvenile fish, indicating its endocrine disrupting potential in fish. Exposure to BKC increased steroid hormone level in H295R cells, and induced cytotoxicity in GH3 cells. HQ values of BKC were determined at greater than one in the ambient water near pharmaceutical manufacturing facilities. Considering high ecological risk and endocrine disrupting potential, long-term consequences of BKC contamination in aquatic ecosystem need to be examined.

4.
Annu Rev Chem Biomol Eng ; 11: 559-585, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32259463

RESUMO

Alongside the rising global water demand, continued stress on current water supplies has sparked interest in using nontraditional source waters for energy, agriculture, industry, and domestic needs. Membrane technologies have emerged as one of the most promising approaches to achieve water security, but implementation of membrane processes for increasingly complex waters remains a challenge. The technical feasibility of membrane processes replacing conventional treatment of alternative water supplies (e.g., wastewater, seawater, and produced water) is considered in the context of typical and emerging water quality goals. This review considers the effectiveness of current technologies (both conventional and membrane based), as well as the potential for recent advancements in membrane research to achieve these water quality goals. We envision the future of water treatment to integrate advanced membranes (e.g., mixed-matrix membranes, block copolymers) into smart treatment trains that achieve several goals, including fit-for-purpose water generation, resource recovery, and energy conservation.

5.
Nutrients ; 12(2)2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32046061

RESUMO

Ginsenoside Rg3, one of the major components in Panax ginseng, has been reported to possess several therapeutic effects including anti-obesity properties. However, its effect on the browning of mature white adipocytes as well as the underlying mechanism remains poorly understood. In this study, we suggested a novel role of Rg3 in the browning of mature 3T3-L1 adipocytes by upregulating browning-related gene expression. The browning effects of Rg3 on differentiated 3T3-L1 adipocytes were evaluated by analyzing browning-related markers using quantitative PCR, immunoblotting, and immunostaining. In addition, the size and sum area of lipid droplets in differentiated 3T3-L1 adipocytes were measured using Oil-Red-O staining. In mature 3T3-L1 adipocytes, Rg3 dose-dependently induced the expression of browning-related genes such as Ucp1, Prdm16, Pgc1α, Cidea, and Dio2. Moreover, Rg3 induced the expression of beige fat-specific genes (CD137 and TMEM26) and lipid metabolism-associated genes (FASN, SREBP1, and MCAD), which indicated the activation of lipid metabolism by Rg3. We also demonstrated that activation of 5' adenosine monophosphate-activated protein kinase (AMPK) is required for Rg3-mediated up-regulation of browning gene expression. Moreover, Rg3 inhibited the accumulation of lipid droplets and reduced the droplet size in mature 3T3-L1 adipocytes. Taken together, this study identifies a novel role of Rg3 in browning of white adipocytes, as well as suggesting a potential mechanism of an anti-obesity effect of Panax ginseng.

6.
J Orthop Surg (Hong Kong) ; 28(1): 2309499019896448, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31903855

RESUMO

PURPOSE: Long-term results of total hip arthroplasty (THA) using highly cross-linked polyethylene (HXLPE) and metal femoral head with more than 10 years of follow-up have already been reported. However, most studies included results with a head size of 28 mm that could affect wear rates. The aim of this study was to evaluate the results of 36-mm metallic femoral heads on first-generation HXLPE in patients less than 60 years of age with a minimum follow-up of 10 years. METHODS: Retrospective analysis included 54 cases from 47 patients. The mean age at the time of surgery was 47.22 years and the mean follow-up period was 131.04 months. Porous-coated cementless acetabular cups (Trilolgy®; Zimmer Inc., Warsaw, Indiana, USA) and HXLPE acetabular liners (Longevity®; Zimmer Inc.) were used for all cases. Acetabular cup abduction angles, anteversion angles, and wear rates of liner were measured using polyWare pro 3D distal version 5.10. RESULTS: The average modified Harris hip score at the final follow-up was 88.48 (range 80-96). Average Merle d'Aubigne and Postel score was 15.57 (range 14-18). There was no acetabular cup or femoral stem failing due to aseptic loosening. The average steady-state wear rate determined using radiographs taken at 1 year postoperatively and at the latest follow-up was 0.053 ± 0.025 mm/year. There were no statistically significant differences in liner wear rate with respect to age, variety of the femoral stem, or liner thickness. CONCLUSION: Results of THA with 36-mm metallic femoral heads on first-generation HXLPE in patients less than 60 years of age were satisfactory.

7.
Environ Int ; 135: 105377, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31841807

RESUMO

In this study, a comprehensive investigation was performed to understand the overall occurrence, relative distribution, and bioaccumulation of seven different groups of POPs, comprising 27 polybrominated diphenyl ethers (PBDEs), 76 polychlorinated biphenyls (PCBs), 23 organochlorine pesticides (OCPs), three hexabromocyclododecanes (HBCDs), and 13 perfluoroalkyl substances (PFASs) as legacy POPs, and 41 polychlorinated naphthalenes (PCNs) and 24 short-chain chlorinated paraffins (SCCPs) as emerging POPs, by monitoring crucian carp, sediment, and river water in the freshwater system. Among the targeted POPs, SCCPs were predominant in sediment and crucian carp (more than 95%), while a dominance of PFASs was observed in river water (92%). Principal component analysis revealed four different groups/patterns of POPs in all media: one for PBDEs, PCBs, and OCPs, another for HBCDs and PFASs, and the two others for PCNs and SCCPs. Also, sexually dimorphic growth-dependent accumulation of legacy POPs was observed in crucian carp such that POPs concentration increased with increasing fish size and males recorded significantly higher levels of POPs compared to females.

8.
Sci Rep ; 9(1): 17889, 2019 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-31784646

RESUMO

Non-SMC condensin I complex subunit H (NCAPH) is a vital gene associated with chromosome stability and is required for proper chromosome condensation and segregation. However, the mechanisms through which NCAPH affects pancreatic cancer (PC) and its molecular function remain unclear. In this study, we examined the role of NCAPH in PC cells. Our results showed that NCAPH was overexpressed in clinical PC specimens (GEPIA) and cell lines. In addition, in NCAPH-knockdown cells, colony formation and proliferation were inhibited, and the cell cycle was arrested at the S and G2/M phases owing to failure of mature chromosome condensation (MCC) in poorly condensed chromosomes. Increased cell death in NCAPH-knockdown cells was found to help initiate apoptosis through the activation of caspase-3 and PARP cleavage. Furthermore, NCAPH-knockdown cells showed an increase in chromosomal aberrations and DNA damage via activation of the DNA damage response (Chk1/Chk2) signaling pathways. These data demonstrated that NCAPH played an important role in cell cycle progression and DNA damage by maintaining chromosomal stability through progression of MCC from poorly condensed chromosomes. Ultimately, NCAPH knockdown induced apoptotic cell death, which was partially mediated by caspase-dependent pathways. These findings highlight the potential role of NCAPH as a therapeutic target for PC.

9.
Cancers (Basel) ; 11(10)2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31627350

RESUMO

The membrane glycoprotein CD200 binds to its receptor CD200R1 and induces tolerance, mainly in cells of the myeloid lineage; however, information regarding its role in solid tumors is limited. Here, we investigated whether CD200 expression, which is enriched mainly in high-grade head and neck squamous cell carcinoma (HNSCC), correlates with cancer progression, particularly the epithelial-to-mesenchymal transition (EMT). The forced overexpression of CD200 in the HNSCC cell line, UMSCC84, not only increased the expression of EMT-related genes, but also enhanced invasiveness. The cleaved cytoplasmic domain of CD200 interacted with ß-catenin in the cytosol, was translocated to the nucleus, and eventually enhanced EMT-related gene expression. CD200 increased the invasiveness of mouse tonsillar epithelium immortalized with E6, E7, and Ras (MEER), a model of tonsillar squamous cell carcinoma. siRNA inhibition of CD200 or extracellular domain of CD200R1 down-regulated the expression of EMT-related genes and decreased invasiveness. Consistently, compared to CD200-null MEER tumors, subcutaneous CD200-expressing MEER tumors showed significantly increased metastatic migration into draining lymph nodes. Our study demonstrates a novel and unique role of CD200 in inducing EMT, suggesting the potential therapeutic target for blocking solid cancer progression.

10.
J Exerc Rehabil ; 15(3): 414-418, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31316934

RESUMO

Nordic walking (NW) is a full body training that can be performed with special pole, and has been recognized as an effective out-door activity which can improve the strength of upper extremity. Most previous studies mainly analyzed the effect of NW on the strength of dominant (DN) hand-grip strength, however, a clear scientific examination is needed whether nondominant (NDN) extremity can also be ameliorated by the NW. Therefore, the aim of our study is to investigate the effectiveness of 8 weeks NW training on the NDN handgrip and shoulder strength in healthy middle-aged women. 29 subjects were randomly divided into three groups: Nordic walking group (NWG, n=10), brisk walking group (BWG, n=11), and control group (CG, n=8). Handgrip and shoulder strength were measured by the hand dynamometer and isokinetic machine. NW training was performed 3 times a week, and had 10-min warm-up, 40-min main program consisted of ALFA (Attention, Long arms, Flat poles, Adaptes) technique and Turbo walking, and 10-min cool-down. In handgrip strength of DN hand and the shoulder flexor strength in the both sides, NWG and BWG showed significantly higher value compared to CG. In the NDN hand, NWG also showed significantly higher strength compared to CG, however, there was no significant difference in the handgrip strength/weight among groups. In NDN shoulder extension, significantly higher improvement was found in NWG and BWG compared to that of CG. In conclusion, our study showed that NW can improve the strength of upper extremity in subjects, and can be better approach to improve the NDN handgrip strength than brisk walking method could.

11.
Lab Chip ; 19(8): 1471-1483, 2019 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-30896011

RESUMO

To monitor airborne nanoparticles at a particular point of interest sensitively and accurately, we developed a compact and inexpensive but highly-precise nanoparticle detection system. The proposed system, based on nucleation light-scattering, consists of two components: a microelectromechanical system (MEMS)-based particle growth chip that grows nanoparticles to micro-sized droplets through condensation and a miniaturized optical particle counter (mini-OPC) that detects individual grown droplets using a light-scattering method. To minimize the dimensions and cost of this system, all elements of the particle growth chip were integrated onto a glass slide through simple photolithography and 3D printing. Moreover, a passive cooling technique was adopted, which eliminated the need for an active cooling system. Thus, our system was much more compact, inexpensive, and power-efficient than conventional nanoparticle detection instruments. Through quantitative experiments using Ag nanoparticles in the size range of 5 to 70 nm, it was found that our system could count extremely small nanoparticles (12.4 nm) by growing them to micrometer-sized droplets. Furthermore, our system could provide an accurate number concentration of nanoparticles (the maximum difference was within 15% compared to the reference instrument), regardless of high (3500 N cm-3) and low (0.05 N cm-3) concentration environments. These results indicate that our system can be applied successfully to the monitoring of nanoparticles in various kinds of fields including not only indoor and outdoor environments but also high-tech industries utilizing cleanrooms, air filtration systems, etc.

12.
Materials (Basel) ; 12(6)2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30871272

RESUMO

In this paper, we demonstrate high-mobility inkjet-printed indium-gallium-zinc-oxide (IGZO) thin-film transistors (TFTs) using a solution-processed Sr-doped Al2O3 (SAO) gate dielectric. Particularly, to enhance to the electrical properties of inkjet-printed IGZO TFTs, a linear-type printing pattern was adopted for printing the IGZO channel layer. Compared to dot array printing patterns (4 × 4 and 5 × 5 dot arrays), the linear-type pattern resulted in the formation of a relatively thin and uniform IGZO channel layer. Also, to improve the subthreshold characteristics and low-voltage operation of the device, a high-k and thin (~10 nm) SAO film was used as the gate dielectric layer. Compared to the devices with SiO2 gate dielectric, the inkjet-printed IGZO TFTs with SAO gate dielectric exhibited substantially high field-effect mobility (30.7 cm²/Vs). Moreover, the subthreshold slope and total trap density of states were also significantly reduced to 0.14 V/decade and 8.4 × 1011/cm²·eV, respectively.

13.
Sci Total Environ ; 655: 408-413, 2019 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-30472642

RESUMO

Concentrated animal feeding operations (CAFOs) have been suggested to be the most significant source of pharmaceutical release into the environment. However, limited information is available on the occurrence of veterinary pharmaceutical residues and the associated ecological risks to the aquatic environment near CAFO areas. In this study, ten commonly used veterinary antibiotics, including sulfonamides, tetracyclines, and cephalosporins, along with three analgesics, were measured in water samples collected from the streams that run near two CAFOs in Korea in 2013 (n = 16) and 2014 (n = 10). In addition, the associated ecological risks were estimated by calculating risk quotient. The pharmaceuticals were detected in a higher amount in the samples collected downstream from the CAFO than in those collected upstream. Acetaminophen, sulfamethazine, sulfathiazole, and oxytetracycline were detected at maximum concentrations of 38.8 µg/L, 21.3 µg/L, 17.4 µg/L, and 16.9 µg/L, respectively. Relatively higher concentrations of pharmaceuticals were observed in locations adjacent to the CAFO and the downstream area, suggesting the influence of the CAFO. Except for acetaminophen, lower concentrations of the target pharmaceuticals were detected in the samples collected during the high-flow season. The concentrations of most of the target pharmaceuticals exceeded the risk quotient of one, suggesting potential ecological effects in the areas affected by CAFOs. Our observations show that the water environment near a CAFO could be heavily affected by veterinary pharmaceuticals and analgesic drugs that are also frequently used among humans. Hence, the ecological consequences of pharmaceutical residues in the water bodies near CAFOs warrant further investigation.


Assuntos
Criação de Animais Domésticos , Monitoramento Ambiental/métodos , Rios/química , Drogas Veterinárias/análise , Poluentes Químicos da Água/análise , Animais , Ecologia , Gado , República da Coreia , Medição de Risco , Estações do Ano
14.
Fish Physiol Biochem ; 45(3): 873-883, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30387033

RESUMO

n-Butyl acrylate (nBA) is one of acrylate esters which has been applied to diverse industrial fields. For unveiling of xeno-estrogenic effects and oxidative stress induction by nBA under two-generational exposure regimen (17 weeks), the biomarkers relevant to an estrogenic effect and oxidative stress were analyzed. Acute toxicity value of nBA in Oryzias latipes was 7.2 mg/L (96 h-LC50). Over exposure time, the significant transcriptional change of cytochrome P450 19A (CYP19A) and vitellogenin 1/2 (VTG1/2) was not observed (one-way ANOVA, P < 0.05), meaning no estrogenic effect of nBA. Significant reduction of glutathione (GSH) content was observed in F0 male and female fish, while in F1 male, the content was increased (P < 0.05). Catalase (CAT) activity of male fish showed the significant decrease in both F0 and F1 fish, showing multi-generational suppressing effect of nBA on CAT activity. But in case of reactive oxygen species (ROS), expression level and glutathione S-transferase (GST) activity were not modulated in response to nBA. These findings suggest that nBA could affect an antioxidant system alteration through GSH depletion and inhibition of CAT activity which could be transferred to the next generation, whereas xeno-estrogenic effect would be questionable.


Assuntos
Acrilatos/toxicidade , Antioxidantes/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Oryzias/genética , Acrilatos/metabolismo , Adaptação Fisiológica/fisiologia , Animais , Feminino , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Fígado/metabolismo , Masculino , Oryzias/metabolismo , Testes de Toxicidade Aguda
15.
Materials (Basel) ; 11(10)2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30275425

RESUMO

A fiber-based single-walled carbon nanotube (SWCNT) thin-film-transistor (TFT) has been proposed. We designed complementary SWCNT TFT circuit based on SPICE simulations, with device parameters extracted from the fabricated fiber-based SWCNT TFTs, such as threshold voltage, contact resistance, and off-/gate-leakage current. We fabricated the SWCNTs CMOS inverter circuits using the selective passivation and n-doping processes on a fiber substrate. By comparing the simulation and experimental results, we could enhance the circuit's performance by tuning the threshold voltage between p-type and n-type TFTs, reducing the source/drain contact resistance and off current level, and maintaining a low output capacitance of the TFTs. Importantly, it was found that the voltage gain, output swing range, and frequency response of the fiber-based inverter circuits can be dramatically improved.

16.
Phys Rev Lett ; 120(18): 180502, 2018 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-29775353

RESUMO

Dynamics of large complex systems, such as relaxation towards equilibrium in classical statistical mechanics, often obeys a master equation that captures essential information from the complexities. Here, we find that thermalization of an isolated many-body quantum state can be described by a master equation. We observe sudden quench dynamics of quantum Ising-like models implemented in our quantum simulator, defect-free single-atom tweezers in conjunction with Rydberg-atom interaction. Saturation of their local observables, a thermalization signature, obeys a master equation experimentally constructed by monitoring the occupation probabilities of prequench states and imposing the principle of the detailed balance. Our experiment agrees with theories and demonstrates the detailed balance in a thermalization dynamics that does not require coupling to baths or postulated randomness.

17.
J Chem Phys ; 148(13): 134310, 2018 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-29626901

RESUMO

Hydrazinium azide (HA) has been investigated at high pressures to 68 GPa using confocal micro-Raman spectroscopy and synchrotron powder x-ray diffraction. The results show that HA undergoes structural phase transitions from solid HA-I to HA-II at 13 GPa, associated with the strengthening of hydrogen bonding, and then to N8 at 40 GPa. The transformation of HA to recently predicted N8 (N≡N+-N--N=N--N-+N≡N) is evident by the emergence of new peaks at 2384 cm-1, 1665 cm-1, and 1165 cm-1, arising from the terminal N≡N stretching, the central N=N stretching, and the N-N stretching, respectively. However, upon decompression, N8 decomposes to ε-N2 below 25 GPa, but the remnant can be seen as low as 3 GPa.

18.
Langmuir ; 34(15): 4634-4639, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29597351

RESUMO

By selective attachment of fluorescent dyes to the core-forming block, we produced patchy micelles of diblock copolymers with fluorophores localized in the micellar cores. From these patchy micelles functionalized with dyes, fluorescent supracolloidal chains in a few micrometers were polymerized by combining the patches in neighboring micelles, indicating that selective modification of the core-forming block delivered the functionality into the supracolloidal chain without altering the polymerization of patchy micelles. Thus, with the same polymerization condition, we were able to produce red-, green-, and blue-emitting supracolloidal chains by varying the fluorescent dyes attached to the core-forming block. In addition, we directly visualized individual supracolloidal chains by fluorescence confocal microscopy as well as by transmission electron microscopy.

19.
Opt Express ; 26(2): 1324-1332, 2018 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-29402007

RESUMO

We demonstrate the use of the ultrafast spatial coherent-control method to resolve the fine-structure two-photon transitions of atomic rubidium. Counter-propagating ultrafast optical pulses with spectral phase and amplitude programmed with our optimized solutions successfully induced the two-photon transitions through 5S1/2-5P1/2-5D and 5S1/2-5P3/2-5D pathways, both simultaneously and at distinct spatial locations. Three different pulse-shaping solutions are introduced that combine amplitude shaping, which avoids direct intermediate resonances, and phase programming, which enables the remaining spectral components to be coherently interfered through the targeted transition pathways. Experiments were performed with a room-temperature vapor cell, and the results agree well with theoretical analysis.

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