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41.
Seongmi Ji Eun Sun Moon Han Byul Noh Hyun Jung Park Seongdae Kim Sung Oh Nagarajan Vinod Chang Won Choi Kilhan Kwak 《International journal of molecular sciences》2022,23(4)
Listeria monocytogenes (Lm) bacterial ghosts (LMGs) were produced by the minimum inhibitory concentration (MIC) of HCl, H2SO4, and NaOH. Acid and alkali effects on the LMGs were compared by in vitro and in vivo analyses. Scanning electron microscope showed that all chemicals form lysis pores on the Lm cell envelopes. Real-time qPCR revealed a complete absence of genomic DNA in HCl- and H2SO4-induced LMGs but not in NaOH-induced LMGs. HCl-, H2SO4- and NaOH-induced LMGs showed weaker or missing protein bands on SDS-PAGE gel when compared to wild-type Lm. Murine macrophages exposed to the HCl-induced LMGs showed higher cell viability than those exposed to NaOH-induced LMGs or wild-type Lm. The maximum level of cytokine expression (TNF-α, iNOS, IFN-γ, and IL-10 mRNA) was observed in the macrophages exposed to NaOH-induced LMGs, while that of IL-1β mRNA was observed in the macrophages exposed to HCl-induced LMGs. To investigate LMGs as a vaccine candidate, mice were divided into PBS buffer-injected, HCl- and NaOH-induced LMGs immunized groups. Mice vaccinated with HCl- and NOH-induced LMGs, respectively, significantly increased in specific IgG antibodies, bactericidal activities of serum, and CD4+ and CD8+ T-cell population. Antigenic Lm proteins reacted with antisera against HCl- and NOH-induced LMGs, respectively. Bacterial loads in HCl- and NaOH-induced LMGs immunized mice were significantly lower than PBS-injected mice after virulent Lm challenges. It suggested that vaccination with LMGs induces both humoral and cell-mediated immune responses and protects against virulent challenges. 相似文献
42.
Ji Yeon Noh Chia-Shan Wu Jennifer A. A. DeLuca Sridevi Devaraj Arul Jayaraman Robert C. Alaniz Xiao-Di Tan Clinton D. Allred Yuxiang Sun 《International journal of molecular sciences》2022,23(4)
Chronic low-grade inflammation is a hallmark of aging, which is now coined as inflamm-aging. Inflamm-aging contributes to many age-associated diseases such as obesity, type 2 diabetes, cardiovascular disease, and inflammatory bowel disease (IBD). We have shown that gut hormone ghrelin, via its receptor growth hormone secretagogue receptor (GHS-R), regulates energy metabolism and inflammation in aging. Emerging evidence suggests that gut microbiome has a critical role in intestinal immunity of the host. To determine whether microbiome is an integral driving force of GHS-R mediated immune-metabolic homeostasis in aging, we assessed the gut microbiome profiles of young and old GHS-R global knockout (KO) mice. While young GHS-R KO mice showed marginal changes in Bacteroidetes and Firmicutes, aged GHS-R KO mice exhibited reduced Bacteroidetes and increased Firmicutes, featuring a disease-susceptible microbiome profile. To further study the role of GHS-R in intestinal inflammation in aging, we induced acute colitis in young and aged GHS-R KO mice using dextran sulfate sodium (DSS). The GHS-R KO mice showed more severe disease activity scores, higher proinflammatory cytokine expression, and decreased expression of tight junction markers. These results suggest that GHS-R plays an important role in microbiome homeostasis and gut inflammation during aging; GHS-R suppression exacerbates intestinal inflammation in aging and increases vulnerability to colitis. Collectively, our finding reveals for the first time that GHS-R is an important regulator of intestinal health in aging; targeting GHS-R may present a novel therapeutic strategy for prevention/treatment of aging leaky gut and inflammatory bowel disease. 相似文献
43.
Noh Seok-Ho Lim Jae-Hwan Ryu Jee-Youl 《International Journal of Control, Automation and Systems》2017,15(5):2193-2202
International Journal of Control, Automation and Systems - This paper presents a new automatic fault diagnosis and detection system for fine pattern interconnects. It is verified by performance of... 相似文献
44.
Sung Hee Han Bong Soo Ko So Hyun Ahn Dong Ouk Noh Hyung Joo Suh 《International Journal of Food Science & Technology》2017,52(6):1417-1424
We investigated the explosive process effect on antioxidant activities of coffee bean. The total polyphenol contents of powdered extract of explosive puffing coffee bean at 0.75 MPa (PEP 7.5) and powdered extract of explosive puffing coffee bean at 0.9 MPa (PEP 9.0) were at a significantly higher than that of the powdered extract of roasting coffee bean (PER) (P < 0.05). PEP 7.5 showed the highest levels of 3‐CQA (86.23 μg mg?1), 4‐CQA (43.71 μg mg?1), and 5‐CQA (31.66 μg mg?1), and PEP 9.0 had also similar levels of chlorogenic acids, with 3‐CQA (77.99 μg mg?1), 4‐CQA (43.71 μg mg?1), and 5‐CQA (30.32 μg mg?1). PEP 7.5 and PEP 9.0 showed relatively higher antioxidant capacities in DPPH, ABTS, taurine, FRAP, and β‐carotene/linoleic acid assays. PEPs partly recovered the HepG2 cell damage induced by t‐BOOH. These results suggest that puffed coffee has beneficial health effects, and could be used for the development of novel processed coffee products. 相似文献
45.
Seung Ho Lee Young Bok Kang Wonsuk Jung Yousung Jung Soohyun Kim Hongseok Noh 《Nanoscale research letters》2013,8(1):487
While flow-induced voltage over a graphene layer has been reported, its origin remains unclear. In our previous study, we suggested different mechanisms for different experimental configurations: phonon dragging effect for the parallel alignment and an enhanced out-of-plane phonon mode for the perpendicular alignment (Appl. Phys. Lett. 102:063116, 2011). In order to further examine the origin of flow-induced voltage, we introduced a transverse flow component by integrating staggered herringbone grooves in the microchannel. We found that the flow-induced voltage decreased significantly in the presence of herringbone grooves in both parallel and perpendicular alignments. These results support our previous interpretation. 相似文献
46.
Md. Golam Mostofa J. H. Noh H. Y. Kim J. H. Ahn D. B. Kang 《Journal of Mechanical Science and Technology》2010,24(8):1623-1629
PMMA optical components that are used as one of the most important parts of high precision equipments and machines are increasingly
replacing the glass due to the various advantages of PMMA. Especially in Light Guide Panels, the PMMA sheet that is used in
Liquid Crystal Displays plays an important role in scattering the incident light and requires very fine machining as the sheet
is directly related to the optical characteristics of the panels. The High Speed End milling and High Speed Shaping processes
that are widely adopted and applied to the precise machining of Light Incident Plane still have quality problems, such as
cracks, breakages, poor waviness, and straightness. This paper presents the tooling device design for machining a Light Incident
Plane through vibration-assisted High Speed Shaping for increasing the optical quality by minimizing the above-mentioned problems.
The cutting tool and the tool post presented in this paper are designed by the authors to increase the magnitude of the cutting
stroke by adopting the resonant frequency without weakening the stiffness and to reduce vibrations during even high speed
feeding. The dynamic characteristics of the cutting tool and the tool post are evaluated through simulation and experiment
as well. The results reveal very appropriate dynamic characteristics for vibration-assisted High Speed Shaping. 相似文献
47.
Keum Hwan Noh Seaung-Suk Lee Hee-Bok Kang Hyuk-Je Jeong Young-Ho Yang Sang-Hyun Oh 《组合铁电体》2013,141(1):353-359
We have investigated the cell signal distributions of ferroelectric random access memories (FeRAMs) using newly developed design scheme, hybrid bit line architecture and their reliability against imprint degradation. Since FeRAMs have relatively large signal distributions due to nonuniform ferroelectric storage capacitors, cell signal interference between neighboring bit lines severely degrades the sensing signal margin. In order to remove the cross-talk noise, hybrid bit line architecture is developed, which is a combination of the conventional folded and open bit line schemes. The lifetime against imprint degradation of FeRAM devices is also increased using hybrid bit line architecture. 相似文献
48.
D. -Y. Kim J. -G. Yoon K. H. Noh S. -I. Kwun S. Y. Jeong George W. Taylor 《Ferroelectrics Letters Section》2001,28(3):67-73
The temperature dependence of dielectric constant of K2ZnCl4 was measured at 10, 20, 40 and 100 kHz in the temperature range between 120 and 250 K. A relaxational dielectric anomaly was observed near 210 K for the first time. It is ascribed to domain wall pinning induced by ferroelastic micro-domains which begin to form around 200 K and behave as defects. The dielectric anomaly disappeared after several thermal cycles of heating and cooling. This may be due to the remnant ferroelastic matrix in the ferroelectric phase. 相似文献
49.
Branched polyethylenimine (b-PEI), an amine-rich polymer, can obtain thermosensitivity by a simple acylation reaction. The resulting N-acylated b-PEI derivatives showed a similar lower critical solution temperature (LCST) transition as their linear correspondent, poly(N-alkyloxazoline). Three acyl groups (propionyl, and isobutyryl, and n-butyryl) were introduced and resulted in LCSTs ranging from 10 °C to 90 °C depending on the structure and environment. The hydrophobicity of N-acylated b-PEI can be controlled by varying the acyl group and degree of acylation. Because the LCST transition is determined by the delicate balance between the hydrophobicity and hydrophilicity of the polymers, an increase of the hydrophobicity in N-acylated b-PEI lowers the transition temperature. Also, N-acylated b-PEI contains tertiary amines as well as unacylated primary or secondary amines which can be protonated during acidification from a pH of 7.4 to a pH of 5.5. The LCST transition was observed at elevated temperatures due to the increase of hydrophilicity by the protonation in the acidic environment. The LCST was also influenced by the salt concentration. A decrease of the LCST was observed as the NaCl concentration increased, probably due to the dominance of the salting-out effect. The very simple introduction of thermosensitivity into pre-existing polymers can be easily applied for the development of various dual or multiple signal-sensitive polymer systems. 相似文献
50.
The independence of processes in queueing systems is generally assumed when developing queueing models. However, real systems often involve several process dependencies, and failure to take these into consideration can lead to serious underestimation of the performance measures. We consider herein a single server queueing system with a Markov renewal process (MRP) for its arrival process and a general service time distribution, and derive the distribution function and correlation coefficient of the departure process. Since the departure process also often corresponds to an arrival process in downstream queues, the results obtained here can be used to derive a better approximation of the performance measures of a non-product form general queueing network. 相似文献