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1.
《Saudi Pharmaceutical Journal》2022,30(6):669-678
BackgroundIschemia reperfusion (I/R) play an imperative role in the expansion of cardiovascular disease. Sinomenine (SM) has been exhibited to possess antioxidant, anticancer, anti-inflammatory, antiviral and anticarcinogenic properties. The aim of the study was scrutinized the cardioprotective effect of SM against I/R injury in rat.MethodsRat were randomly divided into normal control (NC), I/R control and I/R + SM (5, 10 and 20 mg/kg), respectively. Ventricular arrhythmias, body weight and heart weight were estimated. Antioxidant, inflammatory cytokines, inflammatory mediators and plasmin system indicator were accessed.ResultsPre-treated SM group rats exhibited the reduction in the duration and incidence of ventricular fibrillation, ventricular ectopic beat (VEB) and ventricular tachycardia along with suppression of arrhythmia score during the ischemia (30 and 120 min). SM treated rats significantly (P < 0.001) altered the level of antioxidant parameters. SM treatment significantly (P < 0.001) repressed the level of creatine kinase MB (CK-MB), creatine kinase (CK) and troponin I (Tnl). SM treated rats significantly (P < 0.001) repressed the tissue factor (TF), thromboxane B2 (TXB2), plasminogen activator inhibitor 1 (PAI-1) and plasma fibrinogen (Fbg) and inflammatory cytokines and inflammatory mediators.ConclusionOur result clearly indicated that SM plays anti-arrhythmia effect in I/R injury in the rats via alteration of oxidative stress and inflammatory reaction. 相似文献
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A molecular perspective for the use of type IV tyrosine kinase inhibitors as anticancer therapeutics
《Drug discovery today》2022,27(3):808-821
Tyrosine kinases are enzymes that can transfer a phosphate group from ATP to a specific protein tyrosine, serine or threonine residue within a cell, operating as a switch that can turn ‘on’ and ‘off’ causing different physiological alterations in the body. Mutated kinases have been shown to display an equilibrium shift toward the activated state. Types I–III have been studied intensively leading to drugs like imatinib (type II), cobimetinib (type III), among others. It is the same scenario for types V–VII; however, there is a lacuna in information regarding type IV inhibitors, although recently some advances have surfaced. This review aims to accumulate the knowledge gained so far about type IV inhibitors. 相似文献
4.
Mixed lineage leukemia 1(MLL1)是组蛋白甲基转移酶SET家族的成员之一。MLL1与WDR5、RbBP5、Ash2L和DPY-30组成MLL1甲基转移酶复合物调控组蛋白H3的第4位赖氨酸的甲基化水平,对造血系统的发育和血细胞的更新至关重要。部分白血病患者体内存在因MLL1基因易位而产生的致癌蛋白——MLL1融合蛋白,MLL1融合蛋白在发挥其致癌作用时需要功能完整的MLL1酶复合物,故靶向MLL1-WDR5的蛋白-蛋白相互作用成为治疗MLL1融合型白血病的潜在策略。本文对MLL1-WDR5蛋白-蛋白相互作用的生物学机制、结构信息以及抑制剂进行了系统的总结,并结合已报道数据对该领域进行了展望,以期为后续研究提供参考。 相似文献
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《Research in microbiology》2022,173(3):103901
Infections caused by Klebsiella pneumoniae are often difficult to manage due to the high frequency of multidrug resistance, often conferred by efflux pumps. In this study, we analyzed sequence variations of the major RND family multidrug efflux pump AcrB from 387 assembled K. pneumoniae genomes. We confirm that AcrB is a highly-conserved efflux pump in K. pneumoniae, and identified several variants that were prevalent in clinical isolates. Molecular dynamics analyses on two of these variants (L118M and S966A) suggested conformational changes that may correlate with increased drug efflux capabilities. The L118M change resulted in enhanced protein rigidity while the flexibility of drug binding pockets was stable or increased, and the interactions between the proximal pockets and water molecules were stronger. For S966A, the significantly enlarged proximal pocket suggested higher drug accommodation ability. Consistent with these predictions, the L118M and S966A variants conferred a slightly increased ability to grow in the presence of tetracycline and to survive cefoxitin exposure when overexpressed. In summary, our results suggest that the emergence of enhanced-function AcrB variants may be a potential risk for increased antibiotic resistance in clinical K. pneumoniae isolates. 相似文献
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《The Journal of thoracic and cardiovascular surgery》2023,165(1):327-334.e2
ObjectiveSeveral trials have recently reported the safety of pulmonary resection after neoadjuvant immunotherapy with encouraging major pathological response rates. We report the detailed adverse events profile from a recently conducted randomized phase II trial in patients with resectable non–small cell lung cancer treated with neoadjuvant durvalumab alone or with sub-ablative radiation.MethodsWe conducted a randomized phase II trial in patients with non–small cell lung cancer clinical stages I to IIIA who were randomly assigned to receive neoadjuvant durvalumab alone or with sub-ablative radiation (8Gyx3). Secondary end points included the safety of 2 cycles of preoperative durvalumab with and without radiation followed by pulmonary resection. Postoperative adverse events within 30 days were recorded according to the National Cancer Institute Common Terminology Criteria for Adverse Events (version 4.0).ResultsSixty patients were enrolled and randomly assigned, with planned resection performed in 26 patients in each arm. Baseline demographics and clinical variables were balanced between groups. The median operative time was similar between arms: 128 minutes (97-201) versus 146 minutes (109-214) (P = .314). There was no 30- or 90-day mortality. Grade 3/4 adverse events occurred in 10 of 26 patients (38%) after monotherapy and in 10 of 26 patients (38%) after dual therapy. Anemia requiring transfusion and hypotension were the 2 most common adverse events. The median length of stay was similar between arms (5 days vs 4 days, P = .172).ConclusionsIn this randomized trial, the addition of sub-ablative focal radiation to durvalumab in the neoadjuvant setting was not associated with increased mortality or morbidity compared with neoadjuvant durvalumab alone. 相似文献
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Major depressive disorder and other neuropsychiatric disorders are often managed with long-term use of antidepressant medication. Fluoxetine, an SSRI antidepressant, is widely used as a first-line treatment for neuropsychiatric disorders. However, fluoxetine has also been shown to increase the risk of metabolic diseases such as non-alcoholic fatty liver disease. Fluoxetine has been shown to increase hepatic lipid accumulation in vivo and in vitro. In addition, fluoxetine has been shown to alter the production of prostaglandins which have also been implicated in the development of non-alcoholic fatty liver disease. The goal of this study was to assess the effect of fluoxetine exposure on the prostaglandin biosynthetic pathway and lipid accumulation in a hepatic cell line (H4-II-E-C3 cells). Fluoxetine treatment increased mRNA expression of prostaglandin biosynthetic enzymes (Ptgs1, Ptgs2, and Ptgds), PPAR gamma (Pparg), and PPAR gamma downstream targets involved in fatty acid uptake (Cd36, Fatp2, and Fatp5) as well as production of 15-deoxy-Δ12,14PGJ2 a PPAR gamma ligand. The effects of fluoxetine to induce lipid accumulation were attenuated with a PTGS1 specific inhibitor (SC-560), whereas inhibition of PTGS2 had no effect. Moreover, SC-560 attenuated 15-deoxy-Δ12,14PGJ2 production and expression of PPAR gamma downstream target genes. Taken together these results suggest that fluoxetine-induced lipid abnormalities appear to be mediated via PTGS1 and its downstream product 15d-PGJ2 and suggest a novel therapeutic target to prevent some of the adverse effects of fluoxetine treatment. 相似文献
10.
《Zeitschrift für medizinische Physik》2022,32(2):218-227
A magnetic resonance imaging (MRI) sequence independent deep learning technique was developed and validated to generate synthetic computed tomography (sCT) scans for MR guided proton therapy. 47 meningioma patients previously undergoing proton therapy based on pencil beam scanning were divided into training (33), validation (6), and test (8) cohorts. T1, T2, and contrast enhanced T1 (T1CM) MRI sequences were used in combination with the planning CT (pCT) data to train a 3D U-Net architecture with ResNet-Blocks. A hyperparameter search was performed including two loss functions, two group sizes of normalisation, and depth of the network. Training outcome was compared between models trained for each individual MRI sequence and for all sequences combined. The performance was evaluated based on a metric and dosimetric analysis as well as spot difference maps. Furthermore, the influence of immobilisation masks that are not visible on MRIs was investigated. Based on the hyperparameter search, the final model was trained with fixed features per group for the group normalisation, six down-convolution steps, an input size of 128 × 192 × 192, and feature loss. For the test dataset for body/bone the mean absolute error (MAE) values were on average 79.8/216.3 Houndsfield unit (HU) when trained using T1 images, 71.1/186.1 HU for T2, and 82.9/236.4 HU for T1CM. The structural similarity metric (SSIM) ranged from 0.95 to 0.98 for all sequences. The investigated dose parameters of the target structures agreed within 1% between original proton treatment plans and plans recalculated on sCTs. The spot difference maps had peaks at ±0.2 cm and for 98% of all spots the difference was less than 1 cm. A novel MRI sequence independent sCT generator was developed, which suggests that the training phase of neural networks can be disengaged from specific MRI acquisition protocols. In contrast to previous studies, the patient cohort consisted exclusively of actual proton therapy patients (i.e. “real-world data”). 相似文献