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991.
《Saudi Pharmaceutical Journal》2022,30(6):750-763
Cognitive decline is one of the serious complications associated with diabetes mellitus (T2DM) of type-2. In this reported work, the effect of aqueous sukkari dates seed extract (ASSE) was evaluated in T2DM-induced rats. T2DM was induced using intraperitoneal injection of nicotinamide and streptozocin (STZ) administration. The diabetic rats were then treated orally with 200 mg/kg and 400 mg/kg of dates seed extract for 30 days and results were compared with metformin-treated groups. The memory functions were assessed using three maze models. Glucose and insulin levels in the blood and acetylcholine, acetylcholinesterase brain homogenates were estimated. The results showed a significant reduction in transfer latency (TL) (p < 0.001) during the elevated plus maze (EPM) test. The novel object recognition (NOR) test revealed a longer exploration time (p > 0.05) with novel objects and a higher discrimination index (p > 0.05). The Y-maze test also showed a significant increase in the number of entries to the novel arm (p > 0.05) and the total number of entries in the trial (p > 0.01) as well as in test (p > 0.05) sessions. Reduction in blood glucose (p > 0.05) and improvement in blood insulin (p > 0.05) levels were also noted. Improvement in ACh levels (p > 0.001) with 400 mg/kg of ASSE and reduction in AChE (p > 0.001) with both doses of ASSE were also observed in the brain homogenates. The results of ASSE were found comparable with the metformin-treated rats. The estimation of phytochemical constituents displayed a significant presence of phenolic content. Further, molecular modeling studies showed ellagic acid, catechin, and epicatechin as the potential molecule interacting with GSK-3β, α-amylase, and AChE and may be responsible for observed bioactivity. In conclusion, ASSE has the ability to alleviate T2DM-related cognitive impairments. 相似文献
992.
Xiaoxi Lv Chang Liu Shanshan Liu Yunxuan Li Wanyu Wang Ke Li Fang Hua Bing Cui Xiaowei Zhang Jiaojiao Yu Jinmei Yu ZhuoWei Hu 《药学学报(英文版)》2022,12(2):735-746
The cell cycle inhibitor P21 has been implicated in cell senescence and plays an important role in the injury–repair process following lung injury. Pulmonary fibrosis (PF) is a fibrotic lung disorder characterized by cell senescence in lung alveolar epithelial cells. In this study, we report that P21 expression was increased in alveolar epithelial type 2 cells (AEC2s) in a time-dependent manner following multiple bleomycin-induced PF. Repeated injury of AEC2s resulted in telomere shortening and triggered P21-dependent cell senescence. AEC2s with elevated expression of P21 lost their self-renewal and differentiation abilities. In particular, elevated P21 not only induced cell cycle arrest in AEC2s but also bound to P300 and β-catenin and inhibited AEC2 differentiation by disturbing the P300–β-catenin interaction. Meanwhile, senescent AEC2s triggered myofibroblast activation by releasing profibrotic cytokines. Knockdown of P21 restored AEC2-mediated lung alveolar regeneration in mice with chronic PF. The results of our study reveal a mechanism of P21-mediated lung regeneration failure during PF development, which suggests a potential strategy for the treatment of fibrotic lung diseases. 相似文献
993.
Danilo Giffoni de Mello Morais Mata Carlos Amir Carmona Andrea Eisen Maureen Trudeau 《Current oncology (Toronto, Ont.)》2022,29(7):4956
Background: Approximately 75% of breast cancer (BC) is associated with luminal differentiation expressing endocrine receptors (ER). For ER+ HER2− tumors, adjuvant endocrine therapy (ET) is the cornerstone treatment. Although relapse events steadily continue, the ET benefits translate to dramatically lengthen life expectancy with bearable side-effects. This review of ER+ HER2− female BC outlines suitable adjuvant treatment strategies to help guide clinical decision making around appropriate therapy. Methods: A literature search was conducted in Embase, Medline, and the Cochrane Libraries, using ER+ HER−, ET BC keywords. Results: In low-risk patients: five years of ET is the standard option. While Tamoxifen remains the preferred selection for premenopausal women, AI is the choice for postmenopausal patients. In the high-risk category: ET plus/minus OFS with two years of Abemaciclib is recommended. Although extended ET for a total of ten years is an alternative, the optimal AI duration is undetermined; nevertheless an additional two to three years beyond the initial five years may be sufficient. In this postmenopausal group, bisphosphonate is endorsed. Conclusions: Classifying the risk category assists in deciding the treatment route and its optimal duration. Tailoring the breadth of ET hinges on a wide array of factors to be appraised for each individualized case, including weighing its benefits and harms. 相似文献
994.
995.
Belgium has actively participated in clinical research on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) since the beginning of the pandemic to help identify effective and safe treatments for COVID-19. The objective of this review is to provide a picture of the clinical studies carried out in hospitalized patients with COVID-19 in Belgium. We collected data on all randomized, interventional trials in patients with COVID-19 that were registered on two recognized clinical trial registers, started enrollment before 31 December 2021, and included at least one patient in a Belgian center. Data were collected concerning the therapies investigated and the nature of the trials performed. Thirty-three hospitals (32% of all Belgian hospitals) participated in at least one of 28 trials (13 sponsored by the industry and 15 by academic centers) on therapeutics for COVID-19 in hospitalized patients: 7 (25%) evaluated antivirals, 17 (61%) immunomodulators, 2 (7%) anti-coagulants, and 1 (3%) nitric oxide to improve respiratory function. Nineteen (68%) were phase II trials. Only three (11%) of the trials were international platform trials. Despite numerous trials, less than 3% of all Belgian patients hospitalized with COVID-19 participated in a clinical trial on therapeutics. As in many other countries, more efforts could have been made to avoid running small, under-powered, mono- or bicenter trials, to create better collaboration between the different Belgian hospitals, and to participate in more international clinical trials, and more specifically in adaptive, platform trials. 相似文献
996.
Fangfang Chang Chenguang Wang Xueli Wu Yongpeng Liu Juncai Wei Zhengyu Bai Lin Yang 《Materials》2022,15(14)
Electrocatalytic conversion of carbon dioxide (CO2) into specific renewable fuels is an attractive way to mitigate the greenhouse effect and solve the energy crisis. AunCu100-n/C alloy nanoparticles (AunCu100−n/C NPs) with tunable compositions, a highly active crystal plane and a strained lattice were synthesized by the thermal solvent co-reduction method. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) results show that AunCu100−n/C catalysts display a subtle lattice strain and dominant (111) crystal plane, which can be adjusted by the alloy composition. Electrochemical results show that AunCu100−n/C alloy catalysts for CO2 reduction display high catalytic activity; in particular, the Faradaic efficiency of Au75Cu25/C is up to 92.6% for CO at −0.7 V (vs. the reversible hydrogen electrode), which is related to lattice shrinkage and the active facet. This research provides a new strategy with which to design strong and active nanoalloy catalysts with lattice mismatch and main active surfaces for CO2 reduction reaction. 相似文献
997.
Fluorescence properties of quantum dots (QDs) are critically affected by their redox states, which is important for practical applications. In this study, we investigated the optical properties of MoSe2-metallic phase quantum-dots (MoSe2-mQDs) depending on the pH variation, in which the MoSe2-mQDs were dispersed in water with two sizes (Φ~3 nm and 12 nm). The larger MoSe2-mQDs exhibited a large red-shift and broadening of photoluminescence (PL) peak with a constant UV absorption spectra as varying the pH, while the smaller ones showed a small red-shift and peak broadening, but discrete absorption bands in the acidic solution. The excitation wavelength-dependent photoluminescence shows that the PL properties of smaller MoSe2-mQDs are more sensitive to the pH change compared to those of larger ones. From the time-resolved PL spectroscopy, the excitons dominantly decaying with an energy of ~3 eV in pH 2 clearly show the shift of PL peak to the lower energy (~2.6 eV) as the pH increases to 7 and 11 in the smaller MoSe2-mQDs. On the other hand, in the larger MoSe2-mQDs, the exciton decay is less sensitive to the redox states compared to those of the smaller ones. This result shows that the pH variation is more critical to the change of photophysical properties than the size effect in MoSe2-mQDs. 相似文献
998.
Subramanyam Vankadara Monique Danielle Dawson Jia Yi Fong Qin Yao Oh Qi An Ang Boping Liu Hong Yun Chang Judice Koh Xiaoying Koh Qian Wen Tan Joma Joy Cheng San Brian Chia 《ACS medicinal chemistry letters》2022,13(8):1345
The SARS-CoV-2 pandemic is currently causing an unprecedented global health emergency since its emergence in December 2019. In December 2021, the FDA granted emergency use authorization to nirmatrelvir, a SARS-CoV-2 main protease inhibitor, for treating infected patients. This peptidomimetic is designed with a nitrile warhead, which forms a covalent bond to the viral protease. Herein, we investigate nirmatrelvir analogs with different warheads and their inhibitory activities. In addition, antiviral activities against human alphacoronavirus 229E was also investigated along with a cell-based assay. We discovered that the hydroxymethylketone and ketobenzothiazole warheads were equipotent to the nitrile warhead, suggesting that these analogs can also be used for treating coronavirus infections. 相似文献
999.
Avinaash Subramaniam Bumjoon Park Domenick Raphael Michelle Landstrom K. C. Hayes 《Nutrients》2022,14(15)
Objective: Whether dietary carbohydrate (CHO) or fat is more involved in type 2 diabetes (T2DM) induction uncomplicated by dietary fiber was addressed in a spontaneous diabetic model, the diurnal Nile rat that mimics the human condition. Methods: A total of 138 male Nile rats were fed plant-based and animal-based saturated fat where 10% energy as CHO and fat were exchanged across 5 diets keeping protein constant, from 70:10:20 to 20:60:20 as CHO:fat:protein %energy. Diabetes induction was analyzed by: 1. diet composition, i.e., CHO:fat ratio, to study the impact of diet; 2. quintiles of average caloric intake per day to study the impact of calories; 3. quintiles of diabetes severity to study the epigenetic impact on diabetes resistance. Results: High glycemic load (GLoad) was most problematic if coupled with high caloric consumption. Diabetes severity highlighted rapid growth and caloric intake as likely epigenetic factors distorting glucose metabolism. The largest weanling rats ate more, grew faster, and developed more diabetes when the dietary GLoad exceeded their gene-based metabolic capacity for glucose disposal. Diabetes risk increased for susceptible rats when energy intake exceeded 26 kcal/day and the GLoad was >175/2000 kcal of diet and when the diet provided >57% energy as CHO. Most resistant rats ate <25 kcal/day independent of the CHO:fat diet ratio or the GLoad adjusted to body size. Conclusion: Beyond the CHO:fat ratio and GLoad, neither the type of fat nor the dietary polyunsaturated/saturated fatty acid (P/S) ratio had a significant impact, suggesting genetic permissiveness affecting caloric and glucose intake and glucose disposition were key to modulating Nile rat diabetes. Fat became protective by limiting GLoad when it contributed >40% energy and displaced CHO to <50% energy, thereby decreasing the number of diabetic rats and diabetes severity. 相似文献