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排序方式: 共有961条查询结果,搜索用时 875 毫秒
941.
Saad S. Dahham Yasser Tabana Muhammad Asif Marawan Ahmed Dinesh Babu Loiy E. Hassan Mohamed B. Khadeer Ahamed Doblin Sandai Khaled Barakat Arno Siraki Amin M. S. A. Majid 《International journal of molecular sciences》2021,22(19)
Beta-Caryophyllene (BCP), a naturally occurring sesquiterpene abundantly found in cloves, hops, and cannabis, is the active candidate of a relatively new group of vascular-inhibiting compounds that aim to block existing tumor blood vessels. Previously, we have reported the anti-cancer properties of BCP by utilizing a series of in-vitro anti-tumor-related assays using human colorectal carcinoma cells. The present study aimed to investigate the effects of BCP on in-vitro, ex-vivo, and in-vivo models of anti-angiogenic assays and evaluate its anti-cancer activity in xenograft tumor (both ectopic and orthotopic) mice models of human colorectal cancer. Computational structural analysis and an apoptosis antibody array were also performed to understand the molecular players underlying this effect. BCP exhibited strong anti-angiogenic activity by blocking the migration of endothelial cells, tube-like network formation, suppression of vascular endothelial growth factor (VEGF) secretion from human umbilical vein endothelial cells and sprouting of rat aorta microvessels. BCP has a probable binding at Site#0 on the surface of VEGFR2. Moreover, BCP significantly deformed the vascularization architecture compared to the negative control in a chick embryo chorioallantoic membrane assay. BCP showed a remarkable reduction in tumor size and fluorescence molecular tomography signal intensity in all the mice treated with BCP, in a dose-dependent relationship, in ectopic and orthotopic tumor xenograft models, respectively. The histological analysis of the tumor from BCP-treated mice revealed a clear reduction of the density of vascularization. In addition, BCP induced apoptosis through downregulation of HSP60, HTRA, survivin, and XIAP, along with the upregulation of p21 expressions. These results suggest that BCP acts at multiple stages of angiogenesis and could be used as a promising therapeutic candidate to halt the growth of colorectal tumor cells. 相似文献
942.
Anita Sharma Kinshuk Dasgupta Seemita Banerjee Ashwin Patwardhan Dinesh Srivastava Jyeshtharaj B. Joshi 《International Journal of Hydrogen Energy》2017,42(15):10047-10056
Nitrogen atoms were successfully doped into the lattice of carbon nanotubes (hereafter called N-CNT) by chemical vapor deposition in a fluidized bed reactor using a solid precursor Imidazole. X-ray Photoelectron Spectroscopy estimated that ~5.4 atom% of nitrogen was doped in the synthesized CNTs. The successful formation of N-CNTs was also confirmed by Fourier Transforms Infrared Spectroscopy. Transmission electron microscopy revealed the morphological features of N-CNTs and their changes with temperature. The use of fluidized bed resulted in the formation of uniform nature of N-CNTs. In-depth studies of influence of nitrogen doping in CNTs for hydrogen storage was studied by comparing with bare CNTs, also synthesized by a the same fluidized bed reactor. The hydrogen storage capacity for N-CNTs (0.8 wt.%) was enhanced significantly at very low temperature (163 K), compared to bare CNTs (0.28 wt.%). 相似文献
943.
Ghada Alomari Bahaa AlTrad Salehhuddin Hamdan Alaa A. A. Aljabali Mazhar Salim Al Zoubi Khalid AlBatanyeh Janti Qar Gregory J. Eaton Almuthanna K. Alkaraki Walhan Alshaer Saja Haifawi Khairunadwa Jemon Dinesh Kumar Chellappan Kamal Dua Murtaza M. Tambuwala 《IET nanobiotechnology / IET》2021,15(5):473
This study examines the effect of nanoparticles with zinc oxides (ZnONPs) on diabetic nephropathy, which is the primary cause of mortality for diabetic patients with end‐stage renal disease. Diabetes in adult male rats was induced via intraperitoneal injection of streptozotocin. ZnONPs were intraperitoneally administered to diabetic rats daily for 7 weeks. Diabetes was associated with increases in blood glucose level, 24‐h urinary albumin excretion rate, glomerular basement membrane thickness, renal oxidative stress markers, and renal mRNA or protein expression of transforming growth factor‐β1, fibronectin, collagen‐IV, tumour necrosis factor‐α and vascular endothelial growth factor‐A. Moreover, the expression of nephrin and podocin, and the mRNA expression of matrix metalloproteinase‐9 were decreased in the diabetic group. These changes were not detected in the control group and were significantly prevented by ZnONP treatment. These results provide evidence that ZnONPs ameliorate the renal damage induced in a diabetic rat model of nephropathy through improving renal functionality; inhibiting renal fibrosis, oxidative stress, inflammation and abnormal angiogenesis; and delaying the development of podocyte injury. The present findings may help design the clinical application of ZnONPs for protection against the development of diabetic nephropathy. 相似文献
944.
Dinesh Chaudhary Fangchen Chong Trilok Neupane Joonhyeok Choi Jun-Goo Jee 《International journal of molecular sciences》2021,22(24)
Coppers play crucial roles in the maintenance homeostasis in living species. Approximately 20 enzyme families of eukaryotes and prokaryotes are known to utilize copper atoms for catalytic activities. However, small-molecule inhibitors directly targeting catalytic centers are rare, except for those that act against tyrosinase and dopamine-β-hydroxylase (DBH). This study tested whether known tyrosinase inhibitors can inhibit the copper-containing enzymes, ceruloplasmin, DBH, and laccase. While most small molecules minimally reduced the activities of ceruloplasmin and DBH, aside from known inhibitors, 5 of 28 tested molecules significantly inhibited the function of laccase, with the Ki values in the range of 15 to 48 µM. Enzyme inhibitory kinetics classified the molecules as competitive inhibitors, whereas differential scanning fluorimetry and fluorescence quenching supported direct bindings. To the best of our knowledge, this is the first report on organic small-molecule inhibitors for laccase. Comparison of tyrosinase and DBH inhibitors using cheminformatics predicted that the presence of thione moiety would suffice to inhibit tyrosinase. Enzyme assays confirmed this prediction, leading to the discovery of two new dual tyrosinase and DBH inhibitors. 相似文献
945.
AbstractIn this article, the constitutive relations and the governing equations are derived for nonlocal thermoelastic solid in the presence of diffusion. The free vibration of a thermoelastic diffusive cylinder is investigated within the framework of the above newly derived model. Time-harmonic vibration is used to transform the governing equations into a system of ordinary differential equations. The frequency equation is taken under investigation for the survival of a range of possible modes in compact form for traction-free thermal boundary conditions: thermally insulated and isothermal boundary conditions. To explore the vibration analysis from frequency equations, we apply a numerical iteration technique for generating numerical data by taking assistance of the Matlab software. The numerically computed and simulated results for the frequency shift, natural frequency, and the thermoelastic damping are presented graphically. The effect of nonlocality on the above quantities is observed and shown graphically. 相似文献
946.
Recently, pea has developed into a major protein crop in Western Canada. In the search for new food protein resources, small commercial facilities in Canada have engaged in manufacturing protein concentrates from pea by air classification or wet milling techniques. However, the major products from these processes are either crude or refined pea starches. Pea starch has been utilized almost exclusively for industrial application. A major factor, which has an adverse effect on the widespread utilization of pea starch in food industry, it its high extent of retrogradation. This review summarizes the present knowledge on composition, structure and physiochemical properties of smooth and wrinkled seeded pea starches with a view to providing suggestions for needed research to improve the utilization of pea starches in the food industry. 相似文献
947.
Jui-Cheng Kao Dinesh Bhalothia Zan-Xiang Wang Hao-Wu Lin Fan-Gang Tseng Li-Yu Ting Ho-Hsiu Chou Yu-Chieh Lo Jyh-Pin Chou Tsan-Yao Chen 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(40):2303391
A hybrid composite of organic–inorganic semiconductor nanomaterials with atomic Au clusters at the interface decoration (denoted as PF3T@Au-TiO2) is developed for visible–light-driven H2 production via direct water splitting. With a strong electron coupling between the terthiophene groups, Au atoms and the oxygen atoms at the heterogeneous interface, significant electron injection from the PF3T to TiO2 occurs leading to a quantum leap in the H2 production yield (18 578 µmol g−1 h−1) by ≈39% as compared to that of the composite without Au decoration (PF3T@TiO2, 11 321 µmol g−1 h−1). Compared to the pure PF3T, such a result is 43-fold improved and is the best performance among all the existing hybrid materials in similar configurations. With robust process control via industrially applicable methods, it is anticipated that the findings and proposed methodologies can accelerate the development of high-performance eco-friendly photocatalytic hydrogen production technologies. 相似文献
948.
Deep learning has risen in popularity as a face recognition technology in recent years. Facenet, a deep convolutional neural network (DCNN) developed by Google, recognizes faces with 128 bytes per face. It also claims to have achieved 99.96% on the reputed Labelled Faces in the Wild (LFW) dataset. However, the accuracy and validation rate of Facenet drops down eventually, there is a gradual decrease in the resolution of the images. This research paper aims at developing a new facial recognition system that can produce a higher accuracy rate and validation rate on low-resolution face images. The proposed system Extended Openface performs facial recognition by using three different features i) facial landmark ii) head pose iii) eye gaze. It extracts facial landmark detection using Scattered Gated Expert Network Constrained Local Model (SGEN-CLM). It also detects the head pose and eye gaze using Enhanced Constrained Local Neural field (ECLNF). Extended openface employs a simple Support Vector Machine (SVM) for training and testing the face images. The system’s performance is assessed on low-resolution datasets like LFW, Indian Movie Face Database (IMFDB). The results demonstrated that Extended Openface has a better accuracy rate (12%) and validation rate (22%) than Facenet on low-resolution images. 相似文献
949.
Silicon - With an objective of enhancing the device performance of a Nanopillar-based n-CdS/p-CdTe solar cell, an n-ZnO window and p-CdZnTe (CZT) electron reflecting layer has been proposed... 相似文献
950.
Sidharth Kumar Sethi Rupesh Raina Shyam Bihari Bansal Anvitha Soundararajan Maninder Dhaliwal Veena Raghunathan Meenal Kalra Kritika Soni Samit Kumar Mahato Ananya Vadhera Dinesh Kumar Yadav Timothy Bunchman 《Hemodialysis international. International Symposium on Home Hemodialysis》2023,27(3):308-317