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1.
Korean J Physiol Pharmacol ; 28(2): 107-112, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38414393

RESUMO

27-Hydroxycholesterol (27OHChol), a prominent cholesterol metabolite present in the bloodstream and peripheral tissues, is a kind of immune oxysterol that elicits immune response. Recent research indicates the involvement of 27OHChol in metabolic inflammation (meta-inflammation) characterized by chronic responses associated with metabolic irregularities. 27OHChol activates monocytic cells such that they secrete pro-inflammatory cytokines and chemokines, and increase the expression of cell surface molecules such as pattern-recognition receptors that play key roles in immune cell-cell communication and sensing metabolism-associated danger signals. Levels of 27OHChol increase when cholesterol metabolism is disrupted, and the resulting inflammatory responses can contribute to the development and complications of metabolic syndrome, including obesity, insulin resistance, and cardiovascular diseases. Since 27OHChol can induce chronic immune response by activating monocyte-macrophage lineage cells that play a crucial role in meta-inflammation, it is essential to understand the 27OHChol-induced inflammatory responses to unravel the roles and mechanisms of action of this cholesterol metabolite in chronic metabolic disorders.

2.
Genes (Basel) ; 15(1)2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38254959

RESUMO

Microphysogobio longidorsalis is endemic to South Korea and inhabits small areas of the Namhangang, Bukhangang, and Imjingang Rivers in the Hangang River water system. Endemic species usually are more vulnerable than species with a wide distribution. Notably, there is a lack of basic conservation data for M. longidorsalis. We analyzed 19 microsatellite loci in six populations of M. longidorsalis in South Korea to characterize their population structure and genetic diversity. The genetic diversity of the microsatellites was 0.741-0.779, which is lower than that of other freshwater fishes. The pairwise genetic differentiation of microsatellite (FST) values ranged from 0.007 to 0.041, suggesting low genetic differentiation between the populations. The Jojongicheon stream population (CP) had an effective population size of <100. Therefore, conservation efforts are required to prevent inbreeding depression in M. longidorsalis. Discriminant analysis of principal components showed that the Hangang River water system would be a single management unit (MU). Our findings provide fundamental genetic insights for the formulation of conservation strategies for M. longidorsalis.


Assuntos
Cipriniformes , Animais , Genética Populacional , Água Doce , Repetições de Microssatélites/genética , República da Coreia , Variação Genética/genética , Água
3.
Foods ; 12(20)2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37893729

RESUMO

Common prostate diseases such as prostatitis and benign prostatic hyperplasia (BPH) have a high incidence at any age. Cellular stresses, such as reactive oxygen species (ROS) and chronic inflammation, are implicated in prostate enlargement and cancer progression and development. Kaempferol is a flavonoid found in abundance in various plants, including broccoli and spinach, and has been reported to exhibit positive biological activities, such as antioxidant and anti-inflammatory properties. In the present study, we introduced prostate organoids to investigate the protective effects of kaempferol against various cellular stresses. The levels of COX-2, iNOS, p-IκB, a pro-inflammatory cytokine, and ROS were increased by LPS treatment but reversed by kaempferol treatment. Kaempferol activated the nuclear factor erythroid 2-related factor 2(Nrf2)-related pathway and enhanced the mitochondrial quality control proteins PGC-1α, PINK1, Parkin, and Beclin. The increase in mitochondrial ROS and oxygen consumption induced by LPS was stabilized by kaempferol treatment. First, our study used prostate organoids as a novel evaluation platform. Secondly, it was demonstrated that kaempferol could alleviate the mitochondrial damage in LPS-induced induced prostate organoids by reducing the production of mitochondrial ROS.

4.
Front Neurosci ; 17: 1161592, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37638314

RESUMO

Recent developments in artificial neural networks and their learning algorithms have enabled new research directions in computer vision, language modeling, and neuroscience. Among various neural network algorithms, spiking neural networks (SNNs) are well-suited for understanding the behavior of biological neural circuits. In this work, we propose to guide the training of a sparse SNN in order to replace a sub-region of a cultured hippocampal network with limited hardware resources. To verify our approach with a realistic experimental setup, we record spikes of cultured hippocampal neurons with a microelectrode array (in vitro). The main focus of this work is to dynamically cut unimportant synapses during SNN training on the fly so that the model can be realized on resource-constrained hardware, e.g., implantable devices. To do so, we adopt a simple STDP learning rule to easily select important synapses that impact the quality of spike timing learning. By combining the STDP rule with online supervised learning, we can precisely predict the spike pattern of the cultured network in real-time. The reduction in the model complexity, i.e., the reduced number of connections, significantly reduces the required hardware resources, which is crucial in developing an implantable chip for the treatment of neurological disorders. In addition to the new learning algorithm, we prototype a sparse SNN hardware on a small FPGA with pipelined execution and parallel computing to verify the possibility of real-time replacement. As a result, we can replace a sub-region of the biological neural circuit within 22 µs using 2.5 × fewer hardware resources, i.e., by allowing 80% sparsity in the SNN model, compared to the fully-connected SNN model. With energy-efficient algorithms and hardware, this work presents an essential step toward real-time neuroprosthetic computation.

5.
PLoS One ; 18(8): e0289486, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37549180

RESUMO

Although preterm birth (PTB), a birth before 34 weeks of gestation accounts for only less than 3% of total births, it is a critical cause of various perinatal morbidity and mortality. Several studies have been conducted on the association between maternal exposure to PM and PTB, but the results were inconsistent. Moreover, no study has analyzed the risk of PM on PTB among women with cardiovascular diseases, even though those were thought to be highly susceptible to PM considering the cardiovascular effect of PM. Therefore, we aimed to evaluate the effect of PM10 on early PTB according to the period of exposure, using machine learning with data from Korea National Health Insurance Service (KNHI) claims. Furthermore, we conducted subgroup analysis to compare the risk of PM on early PTB among pregnant women with cardiovascular diseases and those without. A total of 149,643 primiparous singleton women aged 25 to 40 years who delivered babies in 2017 were included. Random forest feature importance and SHAP (Shapley additive explanations) value were used to identify the effect of PM10 on early PTB in comparison with other well-known contributing factors of PTB. AUC and accuracy of PTB prediction model using random forest were 0.9988 and 0.9984, respectively. Maternal exposure to PM10 was one of the major predictors of early PTB. PM10 concentration of 5 to 7 months before delivery, the first and early second trimester of pregnancy, ranked high in feature importance. SHAP value showed that higher PM10 concentrations before 5 to 7 months before delivery were associated with an increased risk of early PTB. The probability of early PTB was increased by 7.73%, 10.58%, or 11.11% if a variable PM10 concentration of 5, 6, or 7 months before delivery was included to the prediction model. Furthermore, women with cardiovascular diseases were more susceptible to PM10 concentration in terms of risk for early PTB than those without cardiovascular diseases. Maternal exposure to PM10 has a strong association with early PTB. In addition, in the context of PTB, pregnant women with cardiovascular diseases are a high-risk group of PM10 and the first and early second trimester is a high-risk period of PM10.


Assuntos
Exposição Materna , Material Particulado , Nascimento Prematuro , Nascimento Prematuro/epidemiologia , Material Particulado/efeitos adversos , Estudos de Coortes , Aprendizado de Máquina , Humanos , Feminino , Gravidez , Doenças Cardiovasculares/epidemiologia , Poluentes Atmosféricos/efeitos adversos , República da Coreia , Fatores de Risco , Adulto
6.
Appl Microsc ; 53(1): 7, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37553478

RESUMO

This study investigated the anti-obesity effects of yuja pomace extract fermented with lactic acid bacteria in rats with high-fat diet-induced obesity over a period of eight weeks. Epididymal fat cell size was significantly smaller, by about 33%, in the treatment groups given yuja pomace extract fermented with lactic acid bacteria compared to the CON group. Electron microscopic observation of hepatocyte microstructure showed that the number of lipid droplets was lower in hepatocytes, the number of mitochondria was higher, along with distinct cristae, and the rough endoplasmic reticula were well developed with stacks of cisternae and ribosomes. Thus, it is believed that yuja pomace extract fermented with lactic acid bacteria, by influencing body weight and lipid accumulation, is effective in the prevention and treatment of obesity.

7.
PLoS One ; 18(3): e0283959, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37000887

RESUMO

BACKGROUND: Maternal heart disease is suspected to affect preterm birth (PTB); however, validated studies on the association between maternal heart disease and PTB are still limited. This study aimed to build a prediction model for PTB using machine learning analysis and nationwide population data, and to investigate the association between various maternal heart diseases and PTB. METHODS: A population-based, retrospective cohort study was conducted using data obtained from the Korea National Health Insurance claims database, that included 174,926 primiparous women aged 25-40 years who delivered in 2017. The random forest variable importance was used to identify the major determinants of PTB and test its associations with maternal heart diseases, i.e., arrhythmia, ischemic heart disease (IHD), cardiomyopathy, congestive heart failure, and congenital heart disease first diagnosed before or during pregnancy. RESULTS: Among the study population, 12,701 women had PTB, and 12,234 women had at least one heart disease. The areas under the receiver-operating-characteristic curves of the random forest with oversampling data were within 88.53 to 95.31. The accuracy range was 89.59 to 95.22. The most critical variables for PTB were socioeconomic status and age. The random forest variable importance indicated the strong associations of PTB with arrhythmia and IHD among the maternal heart diseases. Within the arrhythmia group, atrial fibrillation/flutter was the most significant risk factor for PTB based on the Shapley additive explanation value. CONCLUSIONS: Careful evaluation and management of maternal heart disease during pregnancy would help reduce PTB. Machine learning is an effective prediction model for PTB and the major predictors of PTB included maternal heart disease such as arrhythmia and IHD.


Assuntos
Cardiopatias Congênitas , Nascimento Prematuro , Gravidez , Recém-Nascido , Humanos , Feminino , Nascimento Prematuro/epidemiologia , Estudos Retrospectivos , Fatores de Risco , República da Coreia/epidemiologia
8.
Artigo em Inglês | MEDLINE | ID: mdl-36767099

RESUMO

BACKGROUND: This study uses machine learning with large-scale population data to assess the associations of preterm birth (PTB) with dental and gastrointestinal diseases. METHODS: Population-based retrospective cohort data came from Korea National Health Insurance claims for 124,606 primiparous women aged 25-40 and delivered in 2017. The 186 independent variables included demographic/socioeconomic determinants, disease information, and medication history. Machine learning analysis was used to establish the prediction model of PTB. Random forest variable importance was used for identifying major determinants of PTB and testing its associations with dental and gastrointestinal diseases, medication history, and socioeconomic status. RESULTS: The random forest with oversampling data registered an accuracy of 84.03, and the areas under the receiver-operating-characteristic curves with the range of 84.03-84.04. Based on random forest variable importance with oversampling data, PTB has strong associations with socioeconomic status (0.284), age (0.214), year 2014 gastroesophageal reflux disease (GERD) (0.026), year 2015 GERD (0.026), year 2013 GERD (0.024), progesterone (0.024), year 2012 GERD (0.023), year 2011 GERD (0.021), tricyclic antidepressant (0.020) and year 2016 infertility (0.019). For example, the accuracy of the model will decrease by 28.4%, 2.6%, or 1.9% if the values of socioeconomic status, year 2014 GERD, or year 2016 infertility are randomly permutated (or shuffled). CONCLUSION: By using machine learning, we established a valid prediction model for PTB. PTB has strong associations with GERD and infertility. Pregnant women need close surveillance for gastrointestinal and obstetric risks at the same time.


Assuntos
Refluxo Gastroesofágico , Nascimento Prematuro , Feminino , Humanos , Recém-Nascido , Gravidez , Refluxo Gastroesofágico/epidemiologia , Programas Nacionais de Saúde , Nascimento Prematuro/epidemiologia , Estudos Retrospectivos , Fatores Socioeconômicos , Aprendizado de Máquina
9.
Death Stud ; 47(4): 410-420, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35674060

RESUMO

This study aims to investigate the psychometric properties, stability, and predictive validity of the PG-13-K. Two subsamples were used: the first subsample (N = 153), participated at Time 1 only, and the second subsample (N = 184) participated at both Time 1 and Time 2. At each time point, reliability, test-retest reliability, and validity were adequate, and the hypothesized two-factor model indicated good to excellent fit. Moreover, the PG-13-K was able to predict the correlation between prolonged grief disorder (PGD) and negative psychological factors. The PG-13-K is a useful and valid instrument for measuring PGD symptoms in Korean settings.


Assuntos
Pesar , Transtorno do Luto Prolongado , Humanos , Psicometria , Estudos Longitudinais , Reprodutibilidade dos Testes , População do Leste Asiático , República da Coreia
10.
Environ Res ; 219: 115071, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36528046

RESUMO

To remove harmful volatile organic compounds (VOCs) including 2-butanone (methyl ethyl ketone, MEK) emitted from various industrial plants is very important for the clean air. Also, it is worthwhile to recycle porous spent fluid catalytic cracking (SFCC) catalysts from various petroleum refineries in terms of reducing industrial waste and the reuse of discharged resources. Therefore, Mn and Mn-Cu added SFCC (Mn/SFCC and Mn-Cu/SFCC) catalysts were prepared to compare their catalytic efficiencies together with the SFCC catalyst in the ozonation of 2-butanone. Since the SFCC-based catalysts have a structure similar to that of zeolite Y (Y), the Mn-loaded zeolite Y catalyst (Mn/Y) was also prepared to compare its activity for the removal of 2-butanone and ozone to that of the SFCC-based ones at room temperature. Among the five catalysts of this study (Y, Mn/Y, SFCC, Mn/SFCC, and Mn-Cu/SFCC), the Mn-Cu/SFCC and Mn/SFCC catalysts showed the better catalytic decomposition activity than the others. The increased distributions of the Mn3+ species and the Ovacancy sites in Mn/SFCC and Mn-Cu/SFCC catalysts which could supply more available active sites for the 2-butanone and ozone removal would enhance the catalytic activity of them.


Assuntos
Ozônio , Zeolitas , Ozônio/química , Porosidade , Catálise
11.
Nutrients ; 14(23)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36501112

RESUMO

Alcohol and drug overdoses cause liver diseases such as cirrhosis, hepatitis, and liver cancer globally. In particular, an overdose of acetaminophen (APAP), which is generally used as an analgesic and antipyretic agent, is a major cause of acute hepatitis, and cases of APAP-induced liver damage are steadily increasing. Potential antioxidants may inhibit the generation of free radicals and prevent drug-induced liver damage. Among plant-derived natural materials, radishes (RJ) and turnips (RG) have anti-inflammatory, anticancer, and antioxidant properties due to the presence of functional ingredients, such as glucosinolate and isothiocyanate. Although various functions have been reported, in vivo studies on the antioxidant activity of radishes are insufficient. Therefore, we aim to evaluate the hepatoprotective effects of RG and RJ in APAP-induced liver-damaged mice. RG and RJ extracts markedly improved the histological status, such as inflammation and infiltration, of mice liver tissue, significantly decreased the levels of alanine transaminase, aspartate aminotransferase, and malondialdehyde, and significantly increased the levels of glutathione, superoxide dismutase and catalase in the APAP-induced liver-damaged mice. In addition, RG and RJ extracts significantly increased the expression of Nrf-2 and HO-1, which are antioxidative-related factors, and regulated the BAX and BCL-2, thereby showing anti-apoptosis activity. These results indicated that RG and RJ extracts protected mice against acute liver injury, attributed to a reduction in both oxidative stress and apoptosis. These findings have clinical implications for the use of RG and RJ extracts as potential natural candidates for developing hepatoprotective agents.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Hepatopatias , Raphanus , Camundongos , Animais , Acetaminofen/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Estresse Oxidativo , Aspartato Aminotransferases/metabolismo , Alanina Transaminase/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Fígado/metabolismo , Hepatopatias/metabolismo
12.
Nanomaterials (Basel) ; 12(22)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36432255

RESUMO

Li-doped CuSCN films of various compositions were applied as hole-transporting material (HTM) for mesoscopic perovskite solar cells (PSCs). Those films of ~60 nm thickness, spin-coated on the perovskite layer, exhibit significantly higher crystallinity and hole mobility compared with the pristine CuSCN films. Among them, 0.33% Li-doped CuSCN (Li0.33:CuSCN) shows the best performance as the HTM of mesoscopic PSC. Furthermore, by depositing a slight amount of PCPDTBT over the Li0.33:CuSCN layer, the VOC was increased to 1.075 V, resulting in an average PCE of 20.24% and 20.65% for the champion device. These PCE and VOC values are comparable to those of PSC using spiro-OMETAD (PCE: 20.61%, VOC: 1.089 V). Such a remarkable increase can be attributed to the penetration of the PCPDTBT polymer into the grain boundaries of the Li0.33:CuSCN film, and to the interface with the perovskite layer, leading to the removal of defects on the perovskite surface by paving the non-contacting parts, as well as to the tight interconnection of the Li0.33:CuSCN grains. The PSC device with Li0.33:CuSCN showed a high long-term stability similar to that with bare CuSCN, and the introduction of PCPDTBT onto the perovskite/Li0.33:CuSCN further improved device stability, exhibiting 94% of the initial PCE after 100 days.

13.
Sensors (Basel) ; 22(20)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36298304

RESUMO

In this paper, multispectral pedestrian detection is mainly discussed, which can contribute to assigning human-aware properties to automated forklifts to prevent accidents, such as collisions, at an early stage. Since there was no multispectral pedestrian detection dataset in an intralogistics domain, we collected a dataset; the dataset employs a method that aligns image pairs with different domains, i.e. RGB and thermal, without the use of a cumbersome device such as a beam splitter, but rather by exploiting the disparity between RGB sensors and camera geometry. In addition, we propose a multispectral pedestrian detector called SSD 2.5D that can not only detect pedestrians but also estimate the distance between an automated forklift and workers. In extensive experiments, the performance of detection and centroid localization is validated with respect to evaluation metrics used in the driving car domain but with distinct categories, such as hazardous zone and warning zone, to make it more applicable to the intralogistics domain.


Assuntos
Condução de Veículo , Pedestres , Humanos , Acidentes de Trânsito/prevenção & controle , Benchmarking
14.
Nanomaterials (Basel) ; 12(18)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36144885

RESUMO

Effect of structural relaxation (SR) on the electrical characteristics and bias stability of solution-processed zinc-tin oxide (ZTO) thin-film transistors (TFTs) were systematically investigated by controlling the annealing time of the ZTO semiconductor films. Note that SR was found to increase with increased annealing time. Due to the increased SR, the ratio of oxygen vacancies (VO) increased from 21.5% to 38.2%. According to increased VO, the mobility in the saturation region was exhibited by a sixfold increase from 0.38 to 2.41 cm2 V-1 s-1. In addition, we found that the threshold voltage negatively shifted from 3.08 to -0.95 V. Regarding the issue of bias stability, according to increased SR, positive-bias stress of the ZTO TFTs was enhanced, compared with reverse features of negative-bias stress. Our understanding is expected to provide a basic way to improve the electrical characteristics and bias stability of rare-metal-free oxide semiconductor TFTs, which have not been sufficiently studied.

15.
Antioxidants (Basel) ; 10(12)2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34943130

RESUMO

The functionality of soybeans is an important factor in the selection and utilization of excellent soybean cultivars, and isoflavones are representative functional substances in soybeans, which exhibit effects on antioxidants, estrogen activity, and cancer, and prevent cardiovascular diseases. This study analyzed ABTS, DPPH, estrogen, ER (ER) alpha, UCP-1, and NO inhibition activities in 48 types of soybean cultivars, as well as the relationship with 19 isolated types of individual isoflavone derivatives. Statistical analysis was conducted to find individual isoflavone derivatives affecting physiological activities, revealing the high correlation of three types of derivatives: genistein 7-O-(6″-O-acetyl)glucoside (6″-O-acetylgenistin), genistein 7-O-(2″-O-apiosyl)glucoside, and glycitein. Based on these results, 15 types of soybean cultivars were selected (one control type, seven yellow types, six black types, and one green type), which have both high physiological activities and a high content of individual isoflavone derivatives. In addition, these high correlations were further verified through a genome-wide association study (GWAS) to determine the association between activities, substances, and genetic characteristics. This study comprehensively describes the relationship between the specific physiological activities of soybean resources, individual isoflavone derivative substances, and SNPs, which will be utilized for in-depth research, such as selection of excellent soybean resources with specific physiological activities.

16.
Nat Neurosci ; 23(12): 1555-1566, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33199896

RESUMO

Although the pathological contributions of reactive astrocytes have been implicated in Alzheimer's disease (AD), their in vivo functions remain elusive due to the lack of appropriate experimental models and precise molecular mechanisms. Here, we show the importance of astrocytic reactivity on the pathogenesis of AD using GiD, a newly developed animal model of reactive astrocytes, where the reactivity of astrocytes can be manipulated as mild (GiDm) or severe (GiDs). Mechanistically, excessive hydrogen peroxide (H2O2) originated from monoamine oxidase B in severe reactive astrocytes causes glial activation, tauopathy, neuronal death, brain atrophy, cognitive impairment and eventual death, which are significantly prevented by AAD-2004, a potent H2O2 scavenger. These H2O2--induced pathological features of AD in GiDs are consistently recapitulated in a three-dimensional culture AD model, virus-infected APP/PS1 mice and the brains of patients with AD. Our study identifies H2O2 from severe but not mild reactive astrocytes as a key determinant of neurodegeneration in AD.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Astrócitos/metabolismo , Astrócitos/patologia , Peróxido de Hidrogênio/metabolismo , Doença de Alzheimer/psicologia , Animais , Atrofia , Encéfalo/patologia , Morte Celular , Disfunção Cognitiva/patologia , Modelos Animais de Doenças , Humanos , Ativação de Macrófagos , Camundongos , Camundongos Mutantes Neurológicos , Camundongos Transgênicos , Monoaminoxidase/metabolismo , Degeneração Neural/patologia , Neuroglia , Neurônios/patologia , Memória Espacial , Tauopatias/patologia
17.
J Hazard Mater ; 397: 122581, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-32417605

RESUMO

This study focused on the simultaneous removal of NO and SO2 from an industrial flue gas stream. To evaluate the removal efficiency of NO and SO2 using O3 and NH3, the consumption of two reactants (O3 and NH3) in line with the conversion of NO and SO2 was quantified experimentally. In addition, NO and SO2 were converted to valuable fertilizers, NH4NO3 and (NH4)2SO4. To identify a principle strategy to enhance the generation of fertilizer, Fourier transform infrared spectroscopy was used to examine the reaction mechanisms for the formation of NH4NO3 and (NH4)2SO4. Acceleration of SO2 oxidation could be achieved effectively by adding NO to a gas mixture of SO2, NH3, and O3. The formation of HNO3 might be enhanced by the simultaneous feeding of NO and SO2. Particle generation was also 10 times higher for NH3/(NO + SO2) than for NH3/NO and for NH3/SO2, which is a prominent feature of this study. Moreover, the introduction of steam had a positive influence on particle generation. This method offers dual applications for NO and SO2 removal from a flue gas stream and direct fertilizer generation.

18.
J Funct Biomater ; 12(1)2020 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-33383616

RESUMO

Titanium and titanium alloys are promising implant metallic materials because of their high strengths, low elastic moduli, high corrosion resistances, and excellent biocompatibilities. A large difference in elastic modulus between the implant material and bone leads to a stress shielding effect, which increases the probability of implant separation or decrease in the bone density around it. Thus, a lower elastic modulus is required for a better implant metallic material. ß titanium has a lower elastic modulus and high strength and can reduce the probability of the stress shielding effect. In this study, the applicability of the Ti-39Nb-6Zr+0.45Al alloy, obtained by adding a small amount of aluminum to the Ti-39Nb-6Zr alloy, as a biomedical implant material was evaluated. The mechanical properties and biocompatibility of the alloy were evaluated. The biocompatibility of Ti-39Nb-6Zr+0.45Al was similar to that of Ti-39Nb-6Zr according to in vitro and in vivo experiments. In addition, the biological corrosion resistances were evaluated through a corrosion test using a 0.9% NaCl solution, which is equivalent to physiological saline. The corrosion resistance was improved by the addition of Al. The yield strength of the Ti-39Nb-6Zr+0.45Al alloy was improved by approximately 20%. The excellent biocompatibility confirmed its feasibility for use as a biomedical implant material.

19.
ACS Appl Mater Interfaces ; 11(51): 48459-48465, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31818098

RESUMO

Stretchable electrodes, which are essential components of next-generation electronic devices, should be highly conductive under multiaxial tensile strain, durable under repetitive stretching, and patternable for integrating stretchable devices. Herein, a lubricant-added stretchable conductive composite of a polydimethylsiloxane-based elastomer containing silver flakes is reported. The added lubricant minimizes changes in conductivity during stretching and maximizes elastic durability by reducing friction. The conductivity varies from 1933.3 S·cm-1 at 0% strain to 307.5 S·cm-1 at 300% uniaxial stretching and 1264.1 S·cm-1 at 50% biaxial stretching. Furthermore, the composite exhibits high durability, even after 1000 cycles of stretching at 200%, and the conductive composite paste can be applied to fine-linewidth direct writing.

20.
J Med Food ; 22(10): 993-999, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31298611

RESUMO

Obesity is caused by an energy imbalance between food intake and energy expenditure, and has detrimental effects on human health. Platycodon (Platycodon grandiflorum) widely grows in Korea, Japan, and China. It has long been used for food and as a medicinal product. However, the mechanism of the improvement of obesity by platycodon was still not clear. Therefore, we investigated the detailed mechanisms of the antiobesity activity of platycodon extracts. Twenty mice (C57BL/6J) were placed into five groups. The test group received 1 g/kg platycodon extracts. The positive control group received 10 mg/kg orlistat, while the negative control and normal control groups received phosphate-buffered saline. The extracts were given orally daily for 8 weeks. The in vivo treatment of platycodon extracts reduced body weight gain by 7.5%, improved plasma lipid profiles. In the groups given platycodon extracts, leptin was significantly decreased whereas adiponectin was increased. Furthermore, platycodon extracts downregulated lipogenic gene (e.g., lipoprotein lipase, acetyl-CoA carboxylase, and fatty acid synthase) expression and increased lipolysis genes (e.g., carnitine palmitoyltransferase 1α, hormone-sensitive lipase, and uncoupling proteins 2) in liver and white adipose tissue. In addition, platycodon extracts inhibited the expression of key adipogenic transcriptional factors. In conclusion, we have demonstrated that platycodon extracts ameliorate high-fat diet-induced obesity and its related metabolic disease by regulating multiple pathways. Dietary supplementation of platycodon extracts as a functional food and medicinal ingredients may be suitable for prevention and treatment of obesity.


Assuntos
Fármacos Antiobesidade/farmacologia , Obesidade/tratamento farmacológico , Extratos Vegetais/farmacologia , Platycodon/química , Adipogenia/efeitos dos fármacos , Adiponectina/sangue , Tecido Adiposo Branco/metabolismo , Animais , Dieta Hiperlipídica/efeitos adversos , Leptina/sangue , Lipídeos/sangue , Lipogênese/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Fitoterapia , Aumento de Peso/efeitos dos fármacos
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