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991.
Sunglyul Maeng Prasanta Guha Florin Udrea Syed Z. Ali Sumita Santra Julian Gardner Jonghyurk Park Sang‐Hyeob Kim Seung Eon Moon Kang‐Ho Park Jong‐Dae Kim Youngjin Choi William I. Milne 《ETRI Journal》2008,30(4):516-525
This paper proposes a compact, energy‐efficient, and smart gas sensor platform technology for ubiquitous sensor network (USN) applications. The compact design of the platform is realized by employing silicon‐on‐insulator (SOI) technology. The sensing element is fully integrated with SOI CMOS circuits for signal processing and communication. Also, the micro‐hotplate operates at high temperatures with extremely low power consumption, which is important for USN applications. ZnO nanowires are synthesized onto the micro‐hotplate by a simple hydrothermal process and are patterned by a lift‐off to form the gas sensor. The sensor was operated at 200°C and showed a good response to 100 ppb NO2 gas. 相似文献
992.
Anam Asghar Muhammad Naeem Aamir Fatima Akbar Sheikh Naveed Ahmad Mervat A. Elsherif Syed Nasir Abbas Bukhari 《Molecules (Basel, Switzerland)》2022,27(14)
The current study reports the fabrication of co-combination gel using Pregabalin and Withania coagulans fruit extract to validate its effectiveness for neuropathic pain in chronic constriction injury (CCI) rat models. Three topical gels were prepared using Carbopol 934 through a pseudo-ternary phase diagram incorporating the Pregabalin (2.5%), Withania coagulans extract (2%), and co-combination of both Pregabalin (2.5%) and Withania coagulans extract (2%). Gels were characterized. FTIR showed a successful polymeric network of the gel without any interaction. The drug distribution at the molecular level was confirmed by XRD. The AFM images topographically indicated the rough surface of gels with a size range from 0.25 to 330 nm. DSC showed the disappearance of sharp peaks of the drug and extract, showing successful incorporation into the polymeric network of gels. The in vitro drug release of co-combination gel was 73% over 48 h. The mechanism of drug release by combination gel was Higuchi+ fickian with values of n (0.282) and R2 (0.947). An in vivo study for pain assessment via four methods: (i) heat hyperalgesia, (ii) cold allodynia, (iii) mechano-hyperalgesia, and (iv) dynamic mechano-allodynia, confirmed that topical treatment with co-combination gel reduced the pain significantly as indicated by the p value: R1 (p < 0.001), R2 (p < 0.001), R3 (p < 0.015), and R4 (p < 0.0344). The significance order was R2 (****) > R1 (***) > R3 (**) > R4 (*) > R5 (ns). 相似文献
993.
Ali Khan Aini Pervaiz Bushra Ansari Riaz Ullah Syed Muhammad Mukarram Shah Haroon Khan Muhammad Saeed Jan Fida Hussain Mohammad Ijaz Khan Ghadeer M. Albadrani Ahmed E. Altyar Mohamed M. Abdel-Daim 《Molecules (Basel, Switzerland)》2022,27(13)
The objective of the current study was to evaluate the phytochemical and pharmacological potential of the Cornus macrophylla. C. macrophylla belongs to the family Cornaceae. It is locally known as khadang and is used for the treatment of different diseases such as analgesic, tonic, diuretic, malaria, inflammation, allergy, infections, cancer, diabetes, and lipid peroxidative. The crude extract and different fractions of C. macrophyll were evaluated by gas chromatography and mass spectroscopy (GC-MS), which identified the most potent bioactive phytochemicals. The antioxidant ability of C. macrophylla was studied by 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid (ABTS) and 1,1 diphenyl-2-picryl-hydrazyl (DPPH) methods. The crude and subsequent fractions of the C. macrophylla were also tested against anti-inflammatory enzymes using COX-2 (Cyclooxygenase-2) and 5-LOX (5-lipoxygenase) assays. The molecular docking was carried out using molecular operating environment (MOE) software. The GC-MS study of C. macrophylla confirmed forty-eight compounds in ethyl acetate (Et.AC) fraction and revealed that the Et.AC fraction was the most active fraction. The antioxidant ability of the Et.AC fraction showed an IC50 values of 09.54 μg/mL and 7.8 μg/mL against ABTS and DPPH assay respectively. Among all the fractions of C. macrophylla, Et.AC showed excellent activity against COX-2 and 5-LOX enzyme. The observed IC50 values were 93.35 μg/mL against COX-2 and 75.64 μg/mL for 5-LOX respectively. Molecular docking studies supported these in vitro results and confirmed the anti-inflammatory potential of C. macrophylla. C. macrophylla has promising potential as a source for the development of new drugs against inflammation in the future. 相似文献
994.
Sreeharsha Nagaraja Syed Sagheer Ahmed Bharathi D. R. Prakash Goudanavar Rupesh Kumar M. Santosh Fattepur Girish Meravanige Arshia Shariff Predeepkumar Narayanappa Shiroorkar Mohammed Habeebuddin Mallikarjun Telsang 《Molecules (Basel, Switzerland)》2022,27(14)
Diabetes mellitus (DM) and its complications are a severe public health concern due to the high incidence, morbidity, and mortality rates. The present study aims to synthesize and characterize silver nanoparticles (AgNPs) using the aqueous leaf extract of Psidium guajava (PGE) for investigating its antidiabetic activity. Psidium guajava silver nanoparticles (PGAg NPs) were prepared and characterized by various parameters. The in vivo study was conducted using PGE and PGAg NPs in Streptozotocin (STZ)-induced diabetic rats to assess their antidiabetic properties. STZ of 55 mg/kg was injected to induce diabetes. The PGE, PGAg NPs at a dose of 200 and 400 mg/kg and standard drug Metformin (100 mg/kg) were administered daily to diabetic rats for 21 days through the oral route. Blood glucose level, body weight changes, lipid profiles, and histopathology of the rats’ liver and pancreas were examined. In the diabetic rats, PGE and PGAg NPs produced a drastic decrease in the blood glucose level, preventing subsequent weight loss and ameliorating lipid profile parameters. The histopathological findings revealed the improvements in pancreas and liver cells due to the repercussion of PGE and PGAg NPs. A compelling effect was observed in all doses of PGE and PGAg NPs; however, PGAg NPs exhibited a more promising result. Thus, from the results, it is concluded that the synthesized PGAg NPs has potent antidiabetic activity due to its enhanced surface area and smaller particle size of nanoparticles. 相似文献
995.
Ayaz Ali Sher Arshad Iqbal Naveed Muhammad Syed Lal Badshah Abdul-Hamid Emwas Mariusz Jaremko 《Molecules (Basel, Switzerland)》2022,27(7)
Chrozophora tinctoria (Euphorbiaceae) has been used as an emetic, anthelminthic, and cathartic agent in traditional medicine. We used gas chromatography-mass spectrometry (GC-MS) to characterize the composition of ethyl acetate (EAC) and dichloromethane (DCMC) fractions from the whole Chrozophora tinctoria plant. EAC and DCMC fractions were evaluated for acetylcholinesterase (AChE) inhibitory activity and acute toxicity. Their effects on intestinal propulsive movement and spasmogenic activity of the gastrointestinal tract (GIT) muscle were also assessed. The compounds detected in both fractions were mostly fatty acids, with about seven compounds in EAC and 10 in DCMC. These included pharmacologically active compounds such as imipramine, used to treat depression, or hexadecanoic acid methyl ester, an antioxidant. Both EAC and DCMC fractions inhibited acetylcholinesterase (AChE) activity with IC50 values of 10 µg and 130 µg, respectively. Both the fractions were found to be toxic in a dose-dependent manner, inducing emesis at 0.5 g or higher and lethargy and mortality from 3–5 g upwards. Similarly, both of the fractions showed laxative activity in metronidazole- and loperamide-induced constipation models. EAC relaxed the intestinal muscle at a lower dose (1 mg/mL) than DCMC. Similarly, the EAC extract showed a significant relaxation effect (EC50 = 0.67 ± 0.15 mg/mL) on KCL-induced contraction in rabbit jejunum as compared to DCMC (EC50 = 5.04 ± 0.05 mg/kg). The present study strongly supports the folklore that this valuable plant is a cathartic agent. Further work is required to isolate and validate the bioactive compounds that act as diarrheal agents in Chrozophora tinctoria. 相似文献
996.
Vinusha H. Mariwamy Shiva Prasad Kollur Bindya Shivananda Muneera Begum Chandan Shivamallu Chandan Dharmashekara Sushma Pradeep Anisha S. Jain Shashanka K. Prasad Asad Syed Abdallah M. Elgorban Salim Al-Rejaie Joaquín Ortega-Castro Juan Frau Norma Flores-Holguín Daniel Glossman-Mitnik 《Molecules (Basel, Switzerland)》2022,27(4)
997.
Atiqul Bari Syed Muhammad Mukarram Shah Fakhria A. Al-Joufi Syed Wadood Ali Shah Mohammad Shoaib Ismail Shah Muhammad Zahoor Muhammad Naeem Ahmed Mehreen Ghias Syed Muhammad Hassan Shah Atif Ali Khan Khalil 《Molecules (Basel, Switzerland)》2022,27(8)
Different species of Artemisia have been reported to have therapeutic potential in treating various health disorders, including diabetes and memory dysfunction. The present study was planned to evaluate the effects of Artemisia macrocephala Jacquem crude extract and its subfractions as antiamnesic agents in streptozotocin-induced (STZ) diabetic mice. The in vivo behavioral studies were performed using the Y Maze test and novel object recognition test (NORT) test at doses of 100 and 200 mg/kg of crude extract and 75 and 150 mg/kg of fractions. The in vitro and ex vivo anticholinesterase activities, along with biochemical parameters (superoxide dismutase, catalase, glutathione and lipid peroxidation) in the brain, were evaluated. Blood glucose levels were monitored with a glucometer; crude extract and fractions reduced the glucose level considerably, with some differences in the extent of their efficacies. The crude extract and fractions demonstrated significant inhibitory activity against cholinesterases (AChE and BuChE) in vitro. Crude, chloroform and ethyl acetate extract were found to be more potent than the other fractions, with IC50 of Crd-Am = 116.36 ± 1.48 and 240.52 ± 1.35 µg/mL, Chl-Am = 52.68 ± 1.09 and 57.45 ± 1.39 µg/mL and Et-Am = 75.19 ± 1.02 and 116.58 ± 1.09 µg/mL, respectively. Oxidative stress biomarkers like superoxide dismutase, catalase and glutathione levels were elevated, whereas MDA levels were reduced by crude extract and all fractions with little difference in their respective values. The Y-maze test and novel object recognition test demonstrated declines in memory impairment in groups (n = 6) treated with crude extract and fractions as compared to STZ diabetic (amnesic) group. The most active fraction, Chl-Am, was also subjected to isolation of bioactive compounds; three compounds were obtained in pure state and designated as AB-I, AB-II and AB-III. Overall, the results of the study showed that Artemisia macrocephala Jacquem enhanced the memory impairment associated with diabetes, elevated acetylcholine levels and ameliorated oxidative stress. Further studies are needed to explore the beneficial role of the secondary metabolites isolated in the present study as memory enhancers. Toxicological aspects of the extracts are also important and need to be evaluated in other animal models. 相似文献
998.
999.
Syeda Tehreem Saeedur Rahman Muhammad Salman Bhatti Reaz Uddin Muhammad Noman Khan Saba Tauseef Hesham R. El-Seedi Abdullatif Bin Muhsinah Jalal Uddin Syed Ghulam Musharraf 《Molecules (Basel, Switzerland)》2021,26(22)
Angiotensin converting enzyme (ACE) plays a crucial role in regulating blood pressure in the human body. Identification of potential ACE inhibitors from medicinal plants supported the idea of repurposing these medicinal plants against hypertension. A method based on ultra-performance liquid chromatography (UPLC) coupled with a diode array detector (DAD) was used for the rapid screening of plant extracts and purified compounds to determine their ACE inhibitory activity. Hippuryl-histidiyl-leucine (HHL) was used as a substrate, which is converted into hippuric acid (HA) by the action of ACE. A calibration curve of the substrate HHL was developed with the linear regression 0.999. The limits of detection and quantification of this method were found to be 0.134 and 0.4061 mM, respectively. Different parameters of ACE inhibitory assay were optimized, including concentration, incubation time and temperature. The ACE inhibition potential of Adhatoda vasica (methanolic-aqueous extract) and its isolated pyrroquinazoline alkaloids, vasicinol (1), vasicine (2) and vasicinone (3) was evaluated. Compounds 1–3 were characterized by various spectroscopic techniques. The IC50 values of vasicinol (1), vasicine (2) and vasicinone (3) were found to be 6.45, 2.60 and 13.49 mM, respectively. Molecular docking studies of compounds 1–3 were also performed. Among these compounds, vasicinol (1) binds as effectively as captopril, a standard drug of ACE inhibition. 相似文献
1000.
Haya Hussain Shujaat Ahmad Syed Wadood Ali Shah Mehreen Ghias Abid Ullah Shafiq Ur Rahman Zul Kamal Farman Ali Khan Nasir Mehmood Khan Juma Muhammad Mazen Almehmadi Osama Abdulaziz Saad Alghamdi 《Molecules (Basel, Switzerland)》2021,26(23)
Cognitive decline in dementia is associated with deficiency of the cholinergic system. In this study, five mono-carbonyl curcumin analogs were synthesized, and on the basis of their promising in vitro anticholinesterase activities, they were further investigated for in vivo neuroprotective and memory enhancing effects in scopolamine-induced amnesia using elevated plus maze (EPM) and novel object recognition (NOR) behavioral mice models. The effects of the synthesized compounds on the cholinergic system involvement in the brain hippocampus and their binding mode in the active site of cholinesterases were also determined. Compound h2 (p < 0.001) and h3 (p < 0.001) significantly inhibited the cholinesterases and reversed the effects of scopolamine by significantly reducing TLT (p < 0.001) in EPM, while (p < 0.001) increased the time exploring the novel object. The % discrimination index (DI) was significantly increased (p < 0.001) in the novel object recognition test. The mechanism of cholinesterase inhibition was further validated through molecular docking study using MOE software. The results obtained from the in vitro, in vivo and ex vivo studies showed that the synthesized curcumin analogs exhibited significantly higher memory-enhancing potential, and h3 could be an effective neuroprotective agent. However, more study is suggested to explore its exact mechanism of action. 相似文献