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91.
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   
92.
PurposeCurrent clinical guidelines are unclear regarding the association of cardiovascular medication with the risk of acute exacerbation (AE) in patients with asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO).MethodsWe conducted a retrospective cohort study by interrogating the claims database of Taipei Veterans General Hospital. Patients with coexistent fixed airflow limitation and asthma were enrolled as an ACO cohort between 2009 and 2017. Exposure to cardiovascular medications, including angiotensin converting enzyme inhibitors (ACEIs), angiotensin II receptor blockers (ARBs), non-selective beta-blockers, cardioselective beta-blockers, dihydropyridine (DHP) calcium channel blockers (CCBs), and non-DHP CCBs, in 3-month period each served as time-dependent covariates. Patients receiving a cardiovascular medication ≥ 28 cumulative daily doses were defined as respective cardiovascular medication users. Patients were followed up until December 31, 2018. The primary endpoint was severe AE, defined as hospitalization or emergency department visit for either asthma, COPD, or respiratory failure. The secondary outcome was moderate AE.ResultsThe final study cohort consisted of 582 ACO subjects, with a mean follow-up period of 2.98 years. After adjustment, ARB (hazard ratio [HR], 0.64, 95% confidence interval [CI], 0.44–0.93, P = 0.019), cardioselective beta-blocker (HR, 0.29, 95% CI, 0.11–0.72, P = 0.008) and DHP CCB (HR, 0.66, 95% CI, 0.45–0.97, P = 0.035) therapies were associated with lower risks of severe AE. ARB (HR, 0.42, 95% CI, 0.30–0.62, P < 0.001) and DHP CCB (HR, 0.55, 95% CI, 0.38–0.80, P = 0.002) therapies were associated with lower risks of moderate AE. Cardioselective beta-blockers, ARBs, and DHP CCBs were associated with lower risks of severe AE in frequent exacerbators. ACEI, non-selective beta-blocker, or non-DHP CCB use did not change the risk of severe AE.ConclusionsARB, cardioselective beta-blocker, and DHP CCB therapies may lower the risk of AE in patients with ACO.  相似文献   
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94.
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   
95.
This study aimed to compare the background echotexture (BE) between automated breast ultrasound (ABUS) and handheld breast ultrasound (HHUS) and evaluate the correlation of BE with mammographic (MG) density and background parenchymal enhancement (BPE) on magnetic resonance imaging (MRI). A total of 212 women with newly diagnosed breast cancer who had undergone preoperative ABUS, HHUS, MG, and MRI were included. Two breast radiologists blinded to the menopausal status analyzed the BE of the contralateral breasts of the patients with breast cancer in consensus. The MG density and BPE of breast MRI on the radiologic reports were compared with the BE in the ultrasound. We used the cumulative link mixed model to compare the BE and Spearman rank correlation to evaluate the association between BE with MG density and BPE. BE was more heterogeneous in ABUS than in HHUS (P < .001) and in the premenopausal group than in the postmenopausal group (P < .001). The heterogeneity of BE in the premenopausal group was higher with ABUS than with HHUS (P = .013). BE and MG density showed a moderate correlation in the postmenopausal group, but a weak correlation in the premenopausal group. BE and BPE showed moderate correlations only in the premenopausal group. ABUS showed a more heterogeneous BE, especially in the premenopausal group. Therefore, more attention is required to interpret ABUS screening in premenopausal women.  相似文献   
96.
97.
Neurokinin 2 receptor (NK2R), a G protein‐coupled receptor for neurokinin A (NKA), a tachykinin family member, regulates various physiological functions including pain response, relaxation of smooth muscle, dilation of blood vessels, and vascular permeability. However, the precise role and regulation of NK2R expression in cancer cells have not been fully elucidated. In this study, we found that high NK2R gene expression was correlated with the poor survival of colorectal cancer patients, and Interferon (IFN‐α/β) stimulation significantly enhanced NK2R gene expression level of colon cancer cells in a Janus kinas 1/2 (JAK 1/2)‐dependent manner. NKA stimulation augmented viability/proliferation and phosphorylation of Extracellular‐signal‐regulated kinase 1/2 (ERK1/2) levels of IFN‐α/β‐treated colon cancer cells and NK2R blockade by using a selective antagonist reduced the proliferation in vitro. Administration of an NK2R antagonist alone or combined with polyinosinic‐polycytidylic acid, a synthetic analog of double‐stranded RNA, to CT26‐bearing mice significantly suppressed tumorigenesis. NK2R‐overexpressing CT26 cells showed enhanced tumorigenesis and metastatic colonization in both lung and liver after the inoculation into mice. These findings indicate that IFN‐α/β‐mediated NK2R expression is related to the malignancy of colon cancer cells, suggesting that NK2R blockade may be a promising strategy for colon cancers.  相似文献   
98.
Vanadium dioxide (VO2) is one of the extensively studied strongly correlated oxides due to its intriguing insulator–metal transition near room temperature. In this work, we investigated temperature-dependent nanoscale conduction in an epitaxial VO2 film grown on an Al2O3 substrate using conductive-atomic force microscopy (C-AFM). We observed that only the regions near the grain boundaries are conductive, producing intriguing donut patterns in C-AFM images. Such donut patterns were observed in the entire measured temperature range (300–355 K). The current values near the grain boundaries increased by approximately two orders of magnitude with an increase in the temperature, which is consistent with the macroscopic transport data. The spatially-varied conduction behavior is ascribed to the coexistence of different monoclinic phases, i.e., M1 and M2 phases, based on the results of temperature-dependent Raman spectroscopy. Furthermore, we investigated the conduction mechanism in the relatively conductive M1 phase regions at room temperature using current–voltage (IV) spectroscopy and deep data analysis. Bayesian linear unmixing and k-means clustering showed three distinct types of conduction behavior, which classical C-AFM cannot resolve. We found that the conduction in the M1 phase regions can be explained by the Poole–Frenkel mechanism. This work provides deep insight into IMT behavior in the epitaxial VO2 thin film at the nanoscale, especially the coexistence and evolution of the M1 and M2 phases. This work also highlights that IV spectroscopy combined with deep data analysis is very powerful in investigating local transport in complex oxides and various material systems.

We investigated temperature-dependent nanoscale conduction in an epitaxial VO2 film grown on an Al2O3 substrate using conductive-atomic force microscopy and deep data analysis.  相似文献   
99.
100.

Aim of study

In this study, we have investigated the analgesic and anti-arthritic effects of a traditional Chinese medicine (TCM) combination of Lingzhi and San Miao San (SMS) in a rat model of arthritis induced by Freund's complete adjuvant (FCA).

Materials and methods

Sprague–Dawley rats were induced with monoarthritis by single unilateral injection of FCA into the knee joint. The TCM combination was administered to the rats daily by intraperitoneal injection (50 mg/(kg day)) or via oral administration (500 mg/(kg day)) for 7 days before induction of arthritis and 7 days after. Extension angle that provoked struggling behavior, and size and blood flow of the rat knees were measured to give indexes of allodynia, edema, and hyperemia, respectively. The extent of cell infiltration, tissue proliferation, and erosions of joint cartilage provided additional indexes of the arthritis condition.

Results

FCA injection produced significant allodynia, edema, hyperemia, immune cell infiltration, synovial tissue proliferation, and erosions of joint cartilage in the ipsilateral knees compared with the contralateral saline-injected knees. Intraperitoneal injection of the TCM combination (50 mg/(kg day)) suppressed allodynia, edema, and hyperemia in the inflamed knees, and oral administration (500 mg/(kg day)) suppressed edema and hyperemia. Histological examination showed that the TCM administered by either route reduced immune cell infiltration and erosion of joint cartilage.

Conclusions

These findings suggest the Lingzhi and SMS formulation has analgesic and anti-inflammatory effects in arthritic rat knees, and concur to previous clinical studies that showed the TCM combination reduced pain in rheumatoid arthritis patients, and extends its possible benefit to suppression of inflammatory symptoms in these patients.  相似文献   
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