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Two new polyketide glycosides jejuketomycins A (1) and B (2), were isolated from a culture of Streptomyces sp. KCB15JA151. Their chemical structures including the absolute configurations were determined by detailed analyses of the NMR and HRMS data and ECD calculations and spectral data. Compounds 1 and 2 possess an unusual 6/6/8 tricyclic ring system. Biological evaluation with the wound healing assay and time-lapse cell tracking analysis revealed that compounds 1 and 2 have significant inhibitory activities against cancer cell migration with low cytotoxicity.

Two new polyketide glycosides jejuketomycins A (1) and B (2), were isolated from a culture of Streptomyces sp. KCB15JA151.  相似文献   
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Gut microbiota dysbiosis is strongly associated with psychiatric disorders and inflammatory bowel disease (IBD). Herein, we examined whether the fecal microbiota of IBD patients with depression (IBDD) and their gut microbiota culture (iGm) could cause depression and colitis in mice and anti-inflammatory probiotics could mitigate depression in iGm-transplanted or immobilization stress (IS)-exposed mice. Fecal microbiota transplantation (FMT) from IBDD patients, which exhibited Enterobacteriaceae-rich gut microbiota, and its gut microbiota culture (iGm) increased depression-like behaviors in mice. Their treatments heightened the blood lipopolysaccharide (LPS) level and colonic IL-1β and IL-6 expression. However, FMT from healthy volunteers or sulfasalazine treatment alleviated cGm-induced depressive-like behaviors and hippocampal and colonic inflammation in mice. Moreover, oral administration of Lactobacillus plantarum NK151, Bifidobacterium longum NK173, and Bifidobacterium bifidum NK175, which inhibited LPS-induced IL-6 expression in macrophages, alleviated cGm-induced depression-like behaviors, hippocampal NF-κB+Iba1+ cell numbers and IL-1β and IL-6 expression, blood LPS, IL-6, and creatinine levels, and colonic NF-κB+CD11c+ number and IL-1β and IL-6 expression in mice. Treatment with NK151, NK173, or NK175 mitigated immobilization stress (IS)-induced depressive-like behaviors, neuroinflammation, and gut inflammation in mice. NK151, NK173, or NK175 also decreased IS-induced blood LPS, IL-6, and creatinine levels. The transplantation of Enterobacteriaceae-rich gut microbiota can cause depression and colitis, as IS exposure, and anti-inflammatory NK151, NK173, and NK175, may alleviate stress-induced fatigue, depression, and colitis by regulating the expression of proinflammatory and anti-inflammatory cytokines through the suppression of gut bacterial LPS.  相似文献   
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BackgroundIt has been known that the fear of contagion during the coronavirus disease 2019 (COVID-19) creates time delays with subsequent impact on mortality in patients with acute myocardial infarction (AMI). However, difference of time delay and clinical outcome in patients with ST-segment elevation myocardial infarction (STEMI) or non-STEMI between the COVID-19 pandemic and pre-pandemic era has not been fully investigated yet in Korea. The aim of this study was to investigate the impact of COVID-19 pandemic on time delays and clinical outcome in patients with STEMI or non-STEMI compared to the same period years prior.MethodsA total of 598 patients with STEMI (n = 195) or non-STEMI (n = 403) who underwent coronary angiography during the COVID-19 pandemic (February 1 to April 30, 2020) and pre-pandemic era (February 1 to April 30, 2017, 2018, and 2019) were analyzed in this study. Main outcomes were the incidence of time delay, cardiac arrest, and in-hospital death.ResultsThere was 13.5% reduction in the number of patients hospitalized with AMI during the pandemic compared to pre-pandemic era. In patients with STEMI, door to balloon time tended to be longer during the pandemic compared to pre-pandemic era (55.7 ± 12.6 minutes vs. 60.8 ± 13.0 minutes, P = 0.08). There were no significant differences in cardiac arrest (15.6% vs. 10.4%, P = 0.397) and in-hospital mortality (15.6% vs. 10.4%, P = 0.397) between pre-pandemic and the pandemic era. In patients with non-STEMI, symptom to door time was significantly longer (310.0 ± 346.2 minutes vs. 511.5 ± 635.7 minutes, P = 0.038) and the incidence of cardiac arrest (0.9% vs. 3.5%, P = 0.017) and in-hospital mortality (0.3% vs. 2.3%, P = 0.045) was significantly greater during the pandemic compared to pre-pandemic era. Among medications, angiotensin converting enzyme inhibitors/angiotensin type 2 receptor blockers (ACE-I/ARBs) were underused in STEMI (64.6% vs. 45.8%, P = 0.021) and non-STEMI (67.8% vs. 57.0%, P = 0.061) during the pandemic.ConclusionDuring the COVID-19 pandemic, there has been a considerable reduction in hospital admissions for AMI, time delay, and underuse of ACE-I/ARBs for the management of AMI, and this might be closely associated with the excess death in Korea.  相似文献   
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Although silicon dioxide (SiO2), silver (Ag) and iron oxide (Fe2O3) nanoparticles are widely used in diverse applications from food to biomedicine, in vivo toxicities of these nanoparticles exposed via the oral route remain highly controversial. To examine the systemic toxicity of these nanoparticles, well‐dispersed nanoparticles were orally administered to Sprague–Dawley rats daily over a 13‐week period. Based on the results of an acute toxicity and a 14‐day repeated toxicity study, 975.9, 1030.5 and 1000 mg kg–1 were selected as the highest dose of the SiO2, Ag and Fe2O3 nanoparticles, respectively, for the 13‐week repeated oral toxicity study. The SiO2 and Fe2O3 nanoparticles did not induce dose‐related changes in a number of parameters associated with the systemic toxicity up to 975.9 and 1000 mg kg–1, respectively, whereas the Ag nanoparticles resulted in increases in serum alkaline phosphatase and calcium as well as lymphocyte infiltration in liver and kidney, raising the possibility of liver and kidney toxicity induced by the Ag nanoparticles. Compared with the SiO2 and Fe2O3 nanoparticles showing no systemic distribution in all tissues tested, the Ag concentration in sampled blood and organs in the Ag nanoparticle‐treated group significantly increased with a positive and/or dose‐related trend, meaning that the systemic toxicity of the Ag nanoparticles, including liver and kidney toxicity, might be explained by extensive systemic distribution of Ag originating from the Ag nanoparticles. Our current results suggest that further study is required to identify that Ag detected outside the gastrointestinal tract were indeed a nanoparticle form or ionized form. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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Chemotherapy-induced cognitive impairment (CICI) has emerged as a significant medical problem without therapeutic options. Using the platinum-based chemotherapy cisplatin to model CICI, we revealed robust elevations in the adenosine A2A receptor (A2AR) and its downstream effectors, cAMP and CREB, by cisplatin in the adult mouse hippocampus, a critical brain structure for learning and memory. Notably, A2AR inhibition by the Food and Drug Administration–approved A2AR antagonist KW-6002 prevented cisplatin-induced impairments in neural progenitor proliferation and dendrite morphogenesis of adult-born neurons, while improving memory and anxiety-like behavior, without affecting tumor growth or cisplatin’s antitumor activity. Collectively, our study identifies A2AR signaling as a key pathway that can be therapeutically targeted to prevent cisplatin-induced cognitive impairments.  相似文献   
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Background/AimsWe examined the efficacy and safety of tegoprazan as a part of first-line triple therapy for Helicobacter pylori eradication.MethodsA randomized, double-blind, controlled, multicenter study was performed to evaluate whether tegoprazan (50 mg)-based triple therapy (TPZ) was noninferior to lansoprazole (30 mg)-based triple therapy (LPZ) (with amoxicillin 1 g and clarithromycin 500 mg; all administered twice daily for 7 days) for treating H. pylori. The primary endpoint was the H. pylori eradication rate. Subgroup analyses were performed according to the cytochrome P450 (CYP) 2C19 genotype, the minimum inhibitory concentration (MIC) of amoxicillin and clarithromycin, and underlying gastric diseases.ResultsIn total, 350 H. pylori-positive patients were randomly allocated to the TPZ or LPZ group. The H. pylori eradication rates in the TPZ and LPZ groups were 62.86% (110/175) and 60.57% (106/175) in an intention-to-treat analysis and 69.33% (104/150) and 67.33% (101/150) in a per-protocol analysis (non-inferiority test, p=0.009 and p=0.013), respectively. Subgroup analyses according to MICs or CYP2C19 did not show remarkable differences in eradication rate. Both first-line triple therapies were well-tolerated with no notable differences.ConclusionsTPZ is as effective as proton pump inhibitor-based triple therapy and is as safe as first-line H. pylori eradication therapy but does not overcome the clarithromycin resistance of H. pylori in Korea (ClinicalTrials.gov identifier NCT03317223).  相似文献   
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