Exposure to chronic psychological stress may be related to increased reactive oxygen species (ROS) or free radicals, and thus, long-term exposure to high levels of oxidative stress may cause the ...accumulation of oxidative damage and eventually lead to many neurodegenerative diseases. Compared with other organs, the brain appears especially susceptible to excessive oxidative stress due to its high demand for oxygen. In the case of excessive ROS production, endogenous defense mechanisms against ROS may not be sufficient to suppress ROS-associated oxidative damage. Dietary antioxidants have been shown to protect neurons against a variety of experimental neurodegenerative conditions. In particular, Rooibos tea might be a good source of antioxidants due to its larger proportion of polyphenolic compounds. An optimal animal model for stress should show the features of a stress response and should be able to mimic natural stress progression. However, most animal models of stress, such as cold-restraint, electric foot shock, and burn shock, usually involve physical abuse in addition to the psychological aspects of stress. Animals subjected to chronic restraint or immobilization are widely believed to be a convenient and reliable model to mimic psychological stress. Therefore, in the present study, we propose that immobilization-induced oxidative stress was significantly attenuated by treatment with Rooibos tea. This conclusion is demonstrated by Rooibos tea's ability to (i) reverse the increase in stress-related metabolites (5-HIAA and FFA), (ii) prevent lipid peroxidation (LPO), (iii) restore stress-induced protein degradation (PD), (iv) regulate glutathione metabolism (GSH and GSH/GSSG ratio), and (v) modulate changes in the activities of antioxidant enzymes (SOD and CAT).
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To prepare for the potential of extreme drought caused by climate change, both physical and socioeconomic factors need to be considered. In this study, three general circulation models were selected: ...IPSL‐CM5A‐LR, HadGEM2‐AO, and CanESM2 as representative scenarios for severe, moderate, and relatively weak droughts to assess the risk of droughts for future climate projections. Drought hazard was estimated using the meteorological drought index to determine drought frequency, severity, and probability. Population density, agricultural land area, and municipal, agricultural, and industrial water demand were used as drought vulnerability indicators. The Analytical Hierarchy Process technique was applied to determine the weight of each indicator, and the integrated drought risk was then estimated. HadGEM2‐AO and CanESM2 projected that drought risk would be reduced in the far future. IPSL‐CM5A‐LR projected an increased drought risk in the near and far future in the downstream area of the Nakdong River Basin. This study presented a quantitative approach to identify high drought‐risk areas that should be the focus of future extreme drought assessments and mid‐ to long‐term drought mitigation strategies.
Location of the study area and sub‐basin regions. The numbers shown on the map indicate basin identification numbers for the 33 sub‐basins of the Nakdong River, Korea.
Retinoic acid-inducible gene I (RIG-I) is an important innate immune sensor that recognizes viral RNA in the cytoplasm. Its nonself recognition largely depends on the unique RNA structures imposed by ...viral RNA. The panhandle structure residing in the influenza A virus (IAV) genome, whose primary function is to serve as the viral promoter for transcription and replication, has been proposed to be a RIG-I agonist. However, this has never been proved experimentally. Here, we employed multiple approaches to determine if the IAV panhandle structure is directly involved in RIG-I activation and type I interferon (IFN) induction. First, in porcine alveolar macrophages, we demonstrated that the viral genomic coding region is dispensable for RIG-I-dependent IFN induction. Second, using in vitro-synthesized hairpin RNA, we showed that the IAV panhandle structure could directly bind to RIG-I and stimulate IFN production. Furthermore, we investigated the contributions of the wobble base pairs, mismatch, and unpaired nucleotides within the wild-type panhandle structure to RIG-I activation. Elimination of these destabilizing elements within the panhandle structure promoted RIG-I activation and IFN induction. Given the function of the panhandle structure as the viral promoter, we further monitored the promoter activity of these panhandle variants and found that viral replication was moderately affected, whereas viral transcription was impaired dramatically. In all, our results indicate that the IAV panhandle promoter region adopts a nucleotide composition that is optimal for balanced viral RNA synthesis and suboptimal for RIG-I activation.
The IAV genomic panhandle structure has been proposed to be an RIG-I agonist due to its partial complementarity; however, this has not been experimentally confirmed. Here, we provide direct evidence that the IAV panhandle structure is competent in, and sufficient for, RIG-I activation and IFN induction. By constructing panhandle variants with increased complementarity, we demonstrated that the wild-type panhandle structure could be modified to enhance RIG-I activation and IFN induction. These panhandle variants posed moderate influence on viral replication but dramatic impairment of viral transcription. These results indicate that the IAV panhandle promoter region adopts a nucleotide composition to achieve optimal balance of viral RNA synthesis and suboptimal RIG-I activation. Our results highlight the multifunctional role of the IAV panhandle promoter region in the virus life cycle and offer novel insights into the development of antiviral agents aiming to boost RIG-I signaling or virus attenuation by manipulating this conserved region.
Available data is insufficient to identify the influence of visceral adiposity assessed by visceral adiposity index (VAI) on incident MetS. This study was to evaluate the association of VAI with ...incident MetS. In a cohort of Korean genome epidemiology study, 5,807 free of MetS were followed-up for 10 years. They were subdivided into 3 tertile groups according to VAI score. Cox proportional hazard model was used to evaluate the hazard ratios (HRs) and 95% confidential interval (CI) adjusted HRs (95% CI) for MetS according to VAI tertiles. Subgroup analyses were conducted for VAI and waist circumference (WC). Receiver operating characteristic (ROC) and area under curve (AUC) analyses were conducted to compare the discriminative ability for Mets among indices. The risk for MetS increased proportionally to VAI tertiles in all participants, which was similarly observed in both men and women. Subgroup analysis indicated that group with high VAI and low WC had the increased risk for MetS (all participants: 2.76 2.48–3.07, men: 2.77 2.40–3.19 and women: 2.55 2.16–3.00), compared with groups with low VAI and low WC. Group with low VAI and high WC generally had the higher adjusted HRs for MetS than group with the high VAI and low WC. In AUC analyses, WC had the highest discriminative ability for Mets. In conclusion, elevated VAI was significantly associated with the increased long-term risk of MetS. VAI is a useful supplementary to classic anthropometric indices in screening high risk group of MetS.
The 70% ethanol extract of the rhizome of Alisma orientale (Alismatis rhizome) (AOE) was prepared and found to significantly inhibit 5-lipoxygenase (5-LOX)-catalyzed leukotriene (LT) production from ...rat basophilic leukemia (RBL)-1 cells and β-hexosaminidase release by antigen-stimulated RBL-2H3 cells. It also attenuated delayed-type hypersensitivity (DTH) reaction in mice. Among the three major triterpene constituents isolated (i.e., alisol B, alisol B 23-acetate, alisol C 23-acetate) as active principles, alisol B and its 23-acetate strongly and significantly inhibited LT production and β-hexosaminidase release between 1-10 µM. On the other hand, all these alisol derivatives significantly and strongly inhibited DTH response after oral administration. In addition, AOE (200 mg/kg/d) was for the first time found to considerably alleviate hapten-induced dermatitis symptoms in NC/Nga mice, an animal model of atopic dermatitis. These results indicate that alisol derivatives possess inhibitory activities on immediate-type as well as delayed-type hypersensitivity reactions and may contribute to the anti-allergic action of AOE.
As more electrification and emission-free transportation trends receive more attention, electrical systems applied in the aircraft and automotive industries are changing from fossil fuel and ...hydraulic systems to electric AC machine drive systems. Three-dimensional printing technology has been contributing to a new design of machines, because it provides many opportunities without limitation compared to the conventional manufacturing system. Although 3D printing technology opened a door for increasing the efficiency and power density of AC machine drives with low conduction loss, an optimal design process for eddy current loss reduction is required, because eddy current loss is affected by the design structure of the machine. The slit structure at the stator shoe is proposed to reduce eddy current loss. With the three variables, the number of slits, the thickness of slits, and the length of ribs, a parametric analysis was conducted to find an optimal design with eddy current loss reduction without a significant performance dip. The optimal design provides an 18.75% decrease in eddy current loss.
A selective removal of certain ions from aqueous phase containing common ions is very useful in engineering aspect because the process allows removal of toxic substances only or recovery of valuable ...ion species. The ion imprinting technology has shown great potential in the synthesis of materials that are capable of adsorbing a metal ion selectively. In current study, a Pb (II) imprinted magnetic polymer was synthesized using surface imprinting technique employing Pb (II) as template, polyethyleneimene functionalized magnetic Fe 3 O 4 as functional monomer and epoxy chloropropane as cross-linker. The magnetic adsorbent was successfully imprinted, and the ion imprinted sorbent was used for selectivity test for Pb (II). Through the imprinting process, the shape of sorbent has changed, and the magnetic properties have decreased. This is an adverse effect of the polymer formed on the surface of the sorbent by the imprinting. The synthesized magnetic adsorbent was recovered from aqueous phase by a high gradient magnetic separation (HGMS) system with a superconducting magnet. The magnet is a cryo-cooled Nb-Ti superconduction magnet. Magnetic filter (SUS 403, 10 mesh) was used for the magnetic separation. The synthetic polymer with small particle size and weak magnetic properties successfully recovered the by the HGMS system and the recovery efficiency was improved with increased magnetic field of the superconducting magnet. By the magnetic separation, the adsorbent could be recovered and reused after the selective adsorption process for a heavy metal removal. The prepared Pb (II) imprinted magnetic adsorbent was also characterized by transmission electron microscope (TEM) and vibrating sample magnetometer (VSM). Batch selectivity studies were performed to evaluate the influence of competing ions such as Cd (II), Ni (II), and Cu (II). The selectivity coefficients of Pb (II)/Cd (II), Pb (II)/Ni (II) and Pb (II)/Cu (II) were calculated as 1.89, 3.57 and 11.23 respectively.
Schisandrin is the main active ingredient isolated from the fruit of
Schisandra chinensis Baill. Recent studies have demonstrated that schisandrin exhibits anti-oxidative effects
in vivo. In the ...present study, the effect of schisandrin on plasma nitrite concentration in lipopolysaccharide (LPS)-treated mice was evaluated. It also significantly inhibited carrageenan-induced paw edema and acetic acid-induced vascular permeability in mice. Furthermore, schisandrin had a protective effect on lipopolysaccharide (LPS)-induced sepsis.
In vitro, our results are the first that show that the anti-inflammatory properties of schisandrin result from the inhibition of nitric oxide (NO) production, prostaglandin E
2 (PGE
2) release, cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression, which in turn results from the inhibition of nuclear factor-kappaB (NF-κB), c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK) activities in a RAW 264.7 macrophage cell line.
Radiofrequency ablation (RFA) has been widely used to manage hepatocellular carcinomas (HCCs) equal to or smaller than 3 cm. No-touch RFA has gained attention and has recently been implemented in ...local ablation therapy for HCCs, despite its technical complexity, as it provides improved local tumor control compared to conventional tumor-puncturing RFA. This article presents the practice guidelines for performing no-touch RFA for HCCs, which have been endorsed by the Korean Society of Image-Guided Tumor Ablation (KSITA). The guidelines are primarily designed to assist interventional oncologists and address the limitations of conventional tumor-puncturing RFA with describing the fundamental principles, various energy delivery methods, and clinical outcomes of no-touch RFA. The clinical outcomes include technical feasibility, local tumor progression rates, survival outcomes, and potential complications.
To evaluate whether multidetector CT with low-dose radiation (low-dose CT) of joints can be useful when evaluating fractures.
Our study included CT scans of 398 patients, 103 shoulder cases, 109 ...wrist cases, 98 pelvis cases and 88 ankle cases. There were 191 females and 207 males. The low-dose CTs were performed using identical voltage and parameters with the exception of decreased (half of standard dose) tube current. Low-dose and standard-dose images were compared with regards to objective image quality, subjective evaluation of image quality and diagnostic performance for the fractures.
There was no significant difference of image noise between standard-dose CT and low-dose CT in every joint (p > 0.05). Each mean value of subjective score did not show significant difference according to the dosage of the CT scan. There were no statistically significant differences in the sensitivity (96-100%), specificity (95.2-100%) or accuracy (97.9-100%) between standard-dose CT and low-dose CT (p values, 0.1336-1.000).
The evaluation of extremities for fractures using low-dose CT can reduce radiation exposure by about 50% compared with standard-dose CT without affecting image quality or diagnostic performance. Advances in knowledge: Low-dose CT of the extremities (shoulder, pelvis, ankle and wrist) can reduce radiation dose by about 50% compared with standard-dose CT and does not significantly affect image quality or diagnostic performance in fracture detection.
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