Inhibitory role of excessive NH3 in NH3-SCR on CeWOx at low temperatures

The role of Cu species in Cu ion-exchanged IM-5 zeolite (Cu-IM-5) regarding the performance in selective catalytic reduction (SCR) of NOx with NH3 (NH3-SCR) and the reaction mechanism was studied. Based on H2 temperature-programmed reduction (H2-TPR) and electron paramagnetic resonance (EPR) results, Cu–O–Cu and isolated Cu species are suggested as main Cu species existing in Cu-IM-5 and are active for SCR reaction. Cu–O–Cu species show a good NH3-SCR activity at temperatures below 250 °C, whereas their NH3 oxidation activity at higher temperatures hinders the SCR performance. At low temperatures, NH4NO3 and NH4NO2 are key reaction intermediates. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) suggests a mixed Eley–Rideal (E–R) and Langmuir–Hinshelwood (L–H) mechanism over Cu-IM-5 at low temperatures.

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Role of sulphates on the mechanism of NH3-SCR of NO at low temperatures over presulphated vanadium supported on carbon-coated monoliths

Journal of Catalysis ◽

10.1016/j.jcat.2005.04.032 ◽

2005 ◽

Vol 233 (1) ◽

pp. 166-175 ◽

Cited By ~ 40

Author(s):

E GARCIABORDEJE ◽

J PINILLA ◽

M LAZARO ◽

R MOLINER ◽

J FIERRO

Keyword(s):

Low Temperatures ◽

Nh3 Scr ◽

Scr Of No ◽

Carbon Coated

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Effect of Dipyridamole on Spontaneous Platelet Aggregation in Whole Blood Decreases with the Time After Venepuncture: Evidence for the Role of ADP

Thrombosis and Haemostasis ◽

10.1055/s-0038-1645978 ◽

1987 ◽

Vol 58 (02) ◽

pp. 744-748 ◽

Cited By ~ 11

Author(s):

A R Saniabadi ◽

G D O Lowe ◽

J C Barbenel ◽

C D Forbes

Keyword(s):

Platelet Aggregation ◽

Correlation Coefficient ◽

Whole Blood ◽

Blood Platelet ◽

Inhibitory Effect ◽

Time Interval ◽

Adp Receptor ◽

Spontaneous Platelet Aggregation

SummarySpontaneous platelet aggregation (SPA) was studied in human whole blood at 3, 5, 10, 20, 30, 40 and 60 minutes after venepuncture. Using a whole blood platelet counter, SPA was quantified by measuring the fall in single platelet count upon rollermixing aliquots of citrated blood at 37° C. The extent of SPA increased with the time after venepuncture, with a correlation coefficient of 0.819. The inhibitory effect of dipyridamole (Dipy) on SPA was studied: (a) 10 μM at each time interval; (b) 0.5-100 μM at 3 and 30 minutes and (c) 15 μM in combination with 100 μM adenosine, 8 μM 2-chloroadenosine (2ClAd, an ADP receptor blocker) and 50 μM aspirin. There was a rapid decrease in the inhibitory effect of Dipy with the time after venepuncture; the correlation coefficient was -0.533. At all the concentrations studied, Dipy was more effective at 3 minutes than at 30 minutes after venepuncture. A combination of Dipy with adenosine, 2ClAd or aspirin was a more effective inhibitor of SPA than either drug alone. However, when 15 μM Dipy and 10 μM Ad were added together, the inhibitory effect of Dipy was not increased significantly, suggesting that Dipy inhibits platelet aggregation independent of Ad. The increase in SPA with the time after venepuncture was abolished when blood was taken directly into the anticoagulant containing 5 μM 2ClAd. It is suggested that ADP released from the red blood cells is responsible for the increased platelet aggregability with the time after venepuncture and makes a serious contribution to the artifacts of in vitro platelet function studies.

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The Role of the Initiator System in the Synthesis of Acidic Multifunctional Nanoparticles Designed for Molecular Imprinting of Proteins

Periodica Polytechnica Chemical Engineering ◽

10.3311/ppch.15414 ◽

2020 ◽

Vol 65 (1) ◽

pp. 28-41

Author(s):

Marwa Aly Ahmed ◽

Júlia Erdőssy ◽

Viola Horváth

Keyword(s):

Acrylic Acid ◽

Binding Affinity ◽

Molecular Imprinting ◽

Low Temperatures ◽

Ammonium Persulfate ◽

Sodium Bisulfite ◽

Multifunctional Nanoparticles ◽

High Affinity ◽

Initiator System

Multifunctional nanoparticles have been shown earlier to bind certain proteins with high affinity and the binding affinity could be enhanced by molecular imprinting of the target protein. In this work different initiator systems were used and compared during the synthesis of poly (N-isopropylacrylamide-co-acrylic acid-co-N-tert-butylacrylamide) nanoparticles with respect to their future applicability in molecular imprinting of lysozyme. The decomposition of ammonium persulfate initiator was initiated either thermally at 60 °C or by using redox activators, namely tetramethylethylenediamine or sodium bisulfite at low temperatures. Morphology differences in the resulting nanoparticles have been revealed using scanning electron microscopy and dynamic light scattering. During polymerization the conversion of each monomer was followed in time. Striking differences were demonstrated in the incorporation rate of acrylic acid between the tetramethylethylenediamine catalyzed initiation and the other systems. This led to a completely different nanoparticle microstructure the consequence of which was the distinctly lower lysozyme binding affinity. On the contrary, the use of sodium bisulfite activation resulted in similar nanoparticle structural homogeneity and protein binding affinity as the thermal initiation.

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Effect of human galanin on the response of circulating catecholamines to hypoglycemia in man

Acta Endocrinologica ◽

10.1530/eje.0.1330723 ◽

1995 ◽

Vol 133 (6) ◽

pp. 723-728 ◽

Cited By ~ 4

Author(s):

Ettore C degli Uberti ◽

Maria R Ambrosio ◽

Marta Bondanelli ◽

Giorgio Transforini ◽

Alberto Valentini ◽

...

Keyword(s):

Heart Rate ◽

Healthy Subjects ◽

Sympathetic Nerve Activity ◽

Heart Rate Response ◽

Statistical Significance ◽

Inhibitory Effect ◽

Amino Acid Residues ◽

Nerve Activity ◽

Receptor Stimulation

degli Uberti EC, Ambrosio MR, Bondanelli M, Trasforini G, Valentini A, Rossi R, Margutti A, Campo M. Effect of human galanin on the response of circulating catecholamines to hypoglycemia in man. Eur J Endocrinol 1995;133:723–8. ISSN 0804–4643 Human galanin (hGAL) is a neuropeptide with 30 amino acid residues that has been found in the peripheral and central nervous system, where it often co-exists with catecholamines. In order to clarify the possible role of hGAL in the regulation of sympathoadrenomedullary function, the effect of a 60 min infusion of hGAL (80 pmol·kg−1 · min−1) on plasma epinephrine and norepinephrine responses to insulin-induced hypoglycemia in nine healthy subjects was investigated. Human GAL administration significantly reduced both the release of basal norepinephrine and the response to insulin-induced hypoglycemia, whereas it attenuated the epinephrine response by 26%, with the hGAL-induced decrease in epinephrine release failing to achieve statistical significance. Human GAL significantly increased the heart rate in resting conditions and clearly exaggerated the heart rate response to insulin-induced hypoglycemia, whereas it had no effect on the blood pressure. We conclude that GAL receptor stimulation exerts an inhibitory effect on basal and insulin-induced hypoglycemia-stimulated release of norepinephrine. These findings provide further evidence that GAL may modulate sympathetic nerve activity in man but that it does not play an important role in the regulation of adrenal medullary function. Ettore C degli Uberti, Chair of Endocrinology, University of Ferrara, Via Savonarola 9, I-44100 Ferrara, Italy

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Biological role of AKT, and regulation of AKT signaling pathway by thymoquinone: perspectives in cancer therapeutics

Mini-Reviews in Medicinal Chemistry ◽

10.2174/1389557520666201005143818 ◽

2020 ◽

Vol 20 ◽

Author(s):

Md. Junaid ◽

Yeasmin Akter ◽

Syeda Samira Afrose ◽

Mousumi Tania ◽

Md. Asaduzzaman Khan

Keyword(s):

Clinical Trials ◽

Signaling Pathways ◽

Signaling Pathway ◽

Inhibitory Effect ◽

Akt Signaling ◽

Review Article ◽

Therapeutic Drug ◽

Akt Signaling Pathway ◽

Anti Cancer

Background: AKT/PKB is an important enzyme with numerous biological functions, and its overexpression is related to the carcinogenesis. AKT stimulates different signaling pathways that are downstream of activated tyrosine kinases and phosphatidylinositol 3-kinase, hence functions as an important target for anti-cancer drugs. Objective: In this review article, we have interpreted the role of AKT signaling pathways in cancer and natural inhibitory effect of Thymoquinone (TQ) in AKT and its possible mechanism. Method: We have collected the updated information and data on AKT, their role in cancer and inhibitory effect of TQ in AKT signaling pathway from google scholar, PubMed, Web of Science, Elsevier, Scopus and many more. Results: There are many drugs already developed, which can target AKT, but very few among them have passed clinical trials. TQ is a natural compound, mainly found in black cumin, which has been found to have potential anti-cancer activities. TQ targets numerous signaling pathways, including AKT, in different cancers. In fact, many studies revealed that AKT is one of the major targets of TQ. The preclinical success of TQ suggests its clinical studies on cancer. Conclusion: This review article summarizes the role of AKT in carcinogenesis, its potent inhibitors in clinical trials, and how TQ acts as an inhibitor of AKT and TQ’s future as a cancer therapeutic drug.

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The Immunomodulatory Role of G2013 (α-L-Guluronic Acid) on the Expression of TLR2 and TLR4 in HT29 cell line

Current Drug Discovery Technologies ◽

10.2174/1570163815666180226093711 ◽

2019 ◽

Vol 16 (1) ◽

pp. 91-95 ◽

Cited By ~ 4

Author(s):

Hamid Farhang ◽

Laleh Sharifi ◽

Mohammad Mehdi Soltan Dallal ◽

Mona Moshiri ◽

Zahra Norouzbabaie ◽

...

Keyword(s):

Inflammatory Responses ◽

Inflammatory Diseases ◽

Rna Extraction ◽

Cell Plate ◽

Inhibitory Effect ◽

Control Group ◽

Ht29 Cells ◽

Guluronic Acid ◽

Tlr4 Mrna

Background: The non-steroidal anti-inflammatory drugs (NSAIDs) play crucial role in the controlling of inflammatory diseases. Due to the vast side effects of NSAIDs, its use is limited. G2013 or &#945;-L-Guluronic Acid is a new NSAID with immunomodulatory features. Objectives: Considering the leading role of TLRs in inflammatory responses, in this study, we aimed to evaluate G2013 cytotoxicity and its effect on the expression of TLR2 and TLR4 molecules. Methods: HEK293-TLR2 and HEK293-TLR4 cells were cultured and seeded on 96-well cell plate, and MTT assay was performed for detecting the viability of the cells after treatment with different concentrations of G2013. HT29 cells were grown and treated with low and high doses of G2013. After total RNA extraction and cDNA synthesis, quantitative real-time PCR were performed to assess the TLR2 and TLR4 mRNA synthesis. Results: We found that concentrations of ≤125 &#181;g/ml of G2013 had no apparent cytotoxicity effect on the HEK293-TLR2 and -TLR4 cells. Our results indicated that after G2013 treatment (5 &#181;g/ml) in HT29 cells, TLR2 and TLR4 mRNA expression decreased significantly compared with the untreated control group (p=0.02 and p=0.001 respectively). Conclusion: The results of this study revealed that G2013 can down regulate the TLR2 and TLR4 gene expression and exerts its inhibitory effect. Our findings are parallel to our previous finding which showed G2013 ability to down regulate the signaling pathway of TLRs. However, further studies are needed to identify the molecular mechanism of G2013.<p>

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