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991.
Awais Khalid Pervaiz Ahmad Abdulhameed Khan Mayeen Uddin Khandaker Imen Kebaili Md Mottahir Alam Israf Ud Din Saleh Muhammad Zohaib Razzaq Ibad Ur Rehman Habib Ahmad Abbasi Danish Hayat 《RSC advances》2022,12(11):6592
Boron nitride (BN) nanomaterials are rapidly being investigated for potential applications in biomedical sciences due to their exceptional physico-chemical characteristics. However, their safe use demands a thorough understanding of their possible environmental and toxicological effects. The cytotoxicity of boron nitride nanotubes (BNNTs) was explored to see if they could be used in living cell imaging. It was observed that the cytotoxicity of BNNTs is higher in cancer cells (65 and 80%) than in normal cell lines (40 and 60%) for 24 h and 48 h respectively. The influence of multiple experimental parameters such as pH, time, amount of catalyst, and initial dye concentration on percentage degradation efficiency was also examined for both catalyst and dye. The degradation effectiveness decreases (92 to 25%) as the original concentration of dye increases (5–50 ppm) due to a decrease in the availability of adsorption sites. Similarly, the degradation efficiency improves up to 90% as the concentration of catalyst increases (0.01–0.05 g) due to an increase in the adsorption sites. The influence of pH was also investigated, the highest degradation efficiency for MO dye was observed at pH 4. Our results show that lower concentrations of BNNTs can be employed in biomedical applications. Dye degradation properties of BNNTs suggest that it can be a potential candidate as a wastewater and air treatment material.Photocatalytic degradation studies of methyl orange using BNNTs. 相似文献
992.
Sania Naseer Muhammad Aamir Muhammad Aslam Mirza Uzma Jabeen Raja Tahir Muhammad Najam Khan Malghani Qamar Wali 《RSC advances》2022,12(13):7661
ZnO is one of the most promising and efficient semiconductor materials for various light-harvesting applications. Herein, we reported the tuning of optical properties of ZnO nanoparticles (NPs) by co-incorporation of Ni and Ag ions in the ZnO lattice. A sonochemical approach was used to synthesize pure ZnO NPs, Ni–ZnO, Ag–ZnO and Ag/Ni–ZnO with different concentrations of Ni and Ag (0.5%, 2%, 4%, 8%, and 15%) and Ni doped Ag–ZnO solid solutions with 0.25%, 0.5%, and 5% Ni ions. The as-synthesized Ni–Ag–ZnO solid solution NPs were characterized by powdered X-ray diffraction (pXRD), FT-IR spectroscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), UV-vis (UV) spectroscopy, and photoluminescence (PL) spectroscopy. Ni–Ag co-incorporation into a ZnO lattice reduces charge recombination by inducing charge trap states between the valence and conduction bands of ZnO and interfacial transfer of electrons. The Ni doped Ag–ZnO solid solution NPs have shown superior 4-nitrophenol reduction compared to pure ZnO NPs which do not show this reaction. Furthermore, a methylene blue (MB) clock reaction was also performed. Antibacterial activity against E. coli and S. aureus has inhibited the growth pattern of both strains depending on the concentration of catalysts.The synergic effect of Ni and Ag in Ni–Ag–ZnO solid solutions has tuned the optoelectronic properties of ZnO for photoreduction reactions. 相似文献
993.
Stephan Neidhardt Jens Garbade Fabian Emrich Kristin Klaeske Michael A. Borger Sven Lehmann Khalil Jawad Maja-Theresa Dieterlen 《Journal of cardiac failure》2019,25(3):204-212
Background
Oxidative stress due to reactive oxygen species (ROS) production is a key factor in the development of heart failure (HF). This study investigated the thioredoxin (Trx) system, which plays a major role in antioxidant defense, in patients suffering from ischemic (ICM) or dilated (DCM) cardiomyopathy.Methods and Results
Myocardial tissue from ICM (n?=?13) and DCM (n?=?13) patients, as well as septal tissue of patients with aortic stenosis but without diagnosed hypertrophic cardiomyopathy or subaortic stenosis (control; n?=?12), was analyzed for Trx1, Trx-interacting protein (TXNIP) and E3 ligase ITCH (E3 ubiquitin-protein ligase Itchy homolog) expression. Trx-reductase 1 (TXNRD1) amount and activity, cytosolic cytochrome C content, and apoptosis markers were quantified by means of enzyme-linked immunosorbent assay and multiplexing. Compared with control samples, ITCH and Trx1 expression, TXNRD1 amount and activity were reduced and TXNIP expression was increased in ICM (ITCH: P?=?.013; Trx1: P?=?.028; TXNRD1 amount: P?=?.035; TXNRD1 activity: P?=?.005; TXNIP: P?=?.014) but not in DCM samples. A higher level of the downstream apoptosis marker caspase-9 (ICM: 582 ± 262 MFI [P?=?.995]; DCM: 1251 ± 548 MFI [P?=?.002], control: 561 ± 214 MFI) was detected in DCM tissue. A higher expression of Bcl-2 was found in DCM (P?=?.011).Conclusion
The Trx system was impaired in ICM but not in DCM. ITCH appeared to be responsible for the down-regulation of the Trx system. ROS-induced mitochondrial instability appeared to play a role in DCM. 相似文献994.
Sherita Hill Golden Eric Bass Stephen Berry Lee Daugherty Biddison Danelle Cayea Deidra Crews Sanjay Desai Khalil G. Ghanem Carrie Herzke Gregory Kirk Flora Kisuule Rachel Levine Kieren Marr Brian ORourke Pankaj Pasricha Kimberly Peairs Stuart Ray Samuel C. Durso Mark E. Anderson 《The American journal of medicine》2019,132(4):535-543
995.
Ray U Khan GA Chakraborty K Basuroy S Patra SC Girish G Bhattacharya G Sinha AK 《Journal of thrombosis and thrombolysis》2012,33(3):218-229
Insulin inhibits platelet aggregation through nitric oxide synthesis by stimulating platelet insulin activated nitric oxide
synthase. Impaired platelet insulin activated nitric oxide synthase in acute myocardial infarction (AMI) patients had been
reported and thus our aim was to identify and isolate the factors impairing insulin activated nitric oxide in acute myocardial
infarction patients’ plasma and study its effect on platelets aggregation in vitro. The insulin activated nitric oxide synthase
inhibitor was identified as a protein and was purified from the plasma of AMI subjects using DEAE cellulose and Sephadex G-50
column, molecular weight determined by SDS-PAGE, nitric oxide quantified by methaemoglobin method, inhibitor protein quantified
in plasma by immunoblot and ELISA, platelet aggregation studies done using an aggregometer, thromboxane-A2 in the platelets
determined by radioimmunoassay, 125I-insulin radioligand binding studies done using normal subject platelets. The purified nitric oxide synthase inhibitor protein
was ~66 kDa, concentration in AMI subjects’ plasma varied from 114 to 9,090 μM and was undetected in normal subjects’ plasma.
The inhibitor protein competes with insulin for insulin receptor binding sites. The Incubation of the normal subject PRP with
5.0 μM inhibitor for 30 min followed by 0.4 μM ADP addition caused platelet aggregation in vitro, 130 μM aspirin or 400 μU
insulin/ml addition was able to abrogate 0.4 μM ADP induced platelet aggregation even in the presence of 5.0 μM inhibitor.
A potent inhibitory protein against insulin activated nitric oxide synthase in platelets appears in circulation of AMI subjects
impairing nitric oxide production, potentiating ADP induced platelet aggregation and increasing the thromboxane-A2 level in
platelets. 相似文献
996.
997.
Mohsin Ali Khan Furqan Farooq Mohammad Faisal Javed Adeel Zafar Krzysztof Adam Ostrowski Fahid Aslam Seweryn Malazdrewicz Mariusz Malak 《Materials》2022,15(1)
To avoid time-consuming, costly, and laborious experimental tests that require skilled personnel, an effort has been made to formulate the depth of wear of fly-ash concrete using a comparative study of machine learning techniques, namely random forest regression (RFR) and gene expression programming (GEP). A widespread database comprising 216 experimental records was constructed from available research. The database includes depth of wear as a response parameter and nine different explanatory variables, i.e., cement content, fly ash, water content, fine and coarse aggregate, plasticizer, air-entraining agent, age of concrete, and time of testing. The performance of the models was judged via statistical metrics. The GEP model gives better performance with R2 and ρ equals 0.9667 and 0.0501 respectively and meet with the external validation criterion suggested in the previous literature. The k-fold cross-validation also verifies the accurateness of the model by evaluating R2, RSE, MAE, and RMSE. The sensitivity analysis of GEP equation indicated that the time of testing is the influential parameter. The results of this research can help the designers, practitioners, and researchers to quickly estimate the depth of wear of fly-ash concrete thus shortening its ecological susceptibilities that push to sustainable and faster construction from the viewpoint of environmentally friendly waste management. 相似文献
998.
999.
Bassem D. Khalil Roberto Sanchez Tasrina Rahman Carolina Rodriguez-Tirado Stefan Moritsch Alba Rodriguez Martinez Brett Miles Eduardo Farias Mihaly Mezei Ana Rita Nobre Deepak Singh Nupura Kale Karl Christoph Sproll Maria Soledad Sosa Julio A. Aguirre-Ghiso 《The Journal of experimental medicine》2022,219(1)
1000.
Abdullah O. Khan Alexandre Slater Annabel Maclachlan Phillip L.R. Nicolson Jeremy A. Pike Jasmeet S. Reyat Jack Yule Rachel Stapley Julie Rayes Steven G. Thomas Neil V. Morgan 《Haematologica》2022,107(1):243
In specialized cells, the expression of specific tubulin isoforms and their subsequent post-translational modifications drive and coordinate unique morphologies and behaviors. The mechanisms by which b1-tubulin, the platelet and megakaryocyte (MK) lineage restricted tubulin isoform, drives platelet production and function remains poorly understood. We investigated the roles of two key post-translational tubulin polymodifications (polyglutamylation and polyglycylation) on these processes using a cohort of thrombocytopenic patients, human induced pluripotent stem cell derived MK, and healthy human donor platelets. We find distinct patterns of polymodification in MK and platelets, mediated by the antagonistic activities of the cell specific expression of tubulin tyrosine ligase like enzymes and cytosolic carboxypeptidase enzymes. The resulting microtubule patterning spatially regulates motor proteins to drive proplatelet formation in megakaryocytes, and the cytoskeletal reorganization required for thrombus formation. This work is the first to show a reversible system of polymodification by which different cell specific functions are achieved. 相似文献