The current work aims to design and synthesis a new series of isatin derivatives and greatly enhances their cytotoxic activity. The derivatives 3-((bromophenyl) imino)-1-(morpholino (pyridine) ...methyl) indolin-2-one, 2-((oxoindoline) amino) benzoic acid, 3-(thiazolo-imino) indolinone, ethyl-2-((oxoindolin-3-ylidene)amino)-benzothiophene-3-carboxylate, 1-(oxoindoline)-benzo4,5 thieno 2,3-dpyrimidin-4(1H)-one, ethyl-2-(2-oxoindoline) hydrazine-1-carboxylate, N-(mercapto-oxo-pyrimidine)-2-(oxoindoline) hydrazine-1-carboxamide, N-(oxo-thiazolo3,2-a pyrimidine)-2-(oxoindolin-ylidene) hydrazine-carboxamide, 3-((amino-phenyl) amino)-3-hydroxy- indolinone, 3-((amino-phenyl) imino)-indolinone, 2-(2-((oxoindoline) amino) phenyl) isoindolinone, 2-(oxoindoline) hydrazine-carbothioamide, 5'-thioxospiroindoline-3,3'-1,2,4triazolidin-one, 5'-amino-spiroindoline-3,2'-1,3,4thiadiazol-2-one and 3-((2-thioxo-imidazo4,5-bquinoxaline) imino) indolinone were synthesized from the starting material 1-(morpholino (pyridine) methyl) indoline-2,3-dione and evaluated for their in vitro cytotoxic activity against carcinogenic cells. The new chemical structures were evidenced using spectroscopy (IR, NMR and MS) and elemental analysis. The results show that compounds imidazo4,5-bquinoxaline-indolinone, thiazolopyrimidine-oxoindoline, pyrimidine-oxoindoline-hydrazine-carboxamide, spiroindoline-3,2'-1,3,4 thiadiazol-one and spiroindoline-3,3'-1,2,4triazolidin-one have excellent anti-proliferative activities against different human cancer cell lines such as gastric carcinoma cells (MGC-803), breast adenocarcinoma cells (MCF-7), nasopharyngeal carcinoma cells (CNE2) and oral carcinoma cells (KB).
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Ketone bodies (KBs), acetoacetate and β-hydroxybutyrate (βHB), were considered harmful metabolic by-products when discovered in the mid-19th century in the urine of patients with diabetic ...ketoacidosis. It took physicians many years to realize that KBs are normal metabolites synthesized by the liver and exported into the systemic circulation to serve as an energy source for most extrahepatic tissues. Studies have shown that the brain (which normally uses glucose for energy) can readily utilize KBs as an alternative fuel. Even when there is diminished glucose utilization in cognition-critical brain areas, as may occur early in Alzheimer's disease (AD), there is preliminary evidence that these same areas remain capable of metabolizing KBs. Because the ketogenic diet (KD) is difficult to prepare and follow, and effectiveness of KB treatment in certain patients may be enhanced by raising plasma KB levels to ≥2 mM, KB esters, such as 1,3-butanediol monoester of βHB and glyceryl-tris-3-hydroxybutyrate, have been devised. When administered orally in controlled dosages, these esters can produce plasma KB levels comparable to those achieved by the most rigorous KD, thus providing a safe, convenient, and versatile new approach to the study and potential treatment of a variety of diseases, including epilepsy, AD, and Parkinson's disease.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Diverse new azoloazines were synthesized from the reaction of fluorinated hydrazonoyl chlorides with heterocyclic thiones, 1,8‐diaminonaphthalene, ketene aminal derivatives, and ...4‐amino‐5‐triflouromethyl‐1,2,4‐triazole‐2‐thiol. The mechanistic pathways and the structures of all synthesized derivatives were discussed and assured based on the available spectral data. The synthesized azoloazine derivatives were evaluated for their antifungal and antibacterial activities through zone of inhibition measurement. The results revealed promising antifungal activities for compounds 4, 5, 17a,b, 19, and 25 against the pathogenic fungal strains used; Aspergillus flavus and Candida albicans compared to ketoconazole. In addition, compounds 4, 5, 19, and 25 showed moderate antibacterial activities against most tested bacterial strains. Molecular docking studies of the promising compounds were carried out on leucyl‐tRNA synthetase active site of Candida albicans, suggesting good binding in the active site forming stable complexes. Moreover, docking of the synthesized compounds was performed on the active site of SARS‐CoV‐2 3CLpro to predict their potential as a hopeful anti‐COVID and to investigate their binding pattern.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
The purpose of this study is to understand how one of the most non-renewable countries is acting concerning the global challenge of energy supply vs. resources for energy generation. Saudi Arabia is ...registering the highest energy consumption per capita in the world with its fastest population growth and the rapid pace of industrialization. Its electricity consumption is expected to be more than doubled by 2025, and the carbon emission is supposed to be on the rise. In that backdrop, Saudi Arabia has taken many steps to shift its dependency from oil to solar, wind and nuclear sources of energy, and plans to secure half of the country’s electricity needs from the alternative sources of energy in coming 20 years. The government has announced an ambitious plan to install 41 Giga Watt of solar capacity and invest $108.9 billion by 2032. This exploratory study reviews the steps undertaken in this regard to promote the solar energy initiative as envisaged by the government. This paper discusses the issues and challenges in shifting from oil to solar energy in Saudi Arabia. It documents and discusses the drivers that push Saudi Arabia to adopt solar as an alternative source of energy that can be used to reduce oil dependency and to improve environmental sustainability. A multi-pronged approach involving all stakeholders is the key to success in making the solar project sustainable in Saudi Arabia.
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BFBNIB, NUK, PNG, UL, UM, UPUK
Silver nanoparticles (AgNPs) exhibit strong antimicrobial properties against many pathogens. Traditionally employed chemical methods for AgNPs synthesis are toxic for the environment. Here, we report ...a quicker, simpler, and environmentally benign process to synthesize AgNPs by using an aqueous 'root extract' of Salvadora persica (Sp) plant as a reducing agent. The synthesized Salvadora persica nano particles (SpNPs) showed significantly higher antimicrobial efficacy compared to earlier reported studies. We characterized SpNPs using UV-Vis spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), Transmission Electron Microscopy (TEM), Field Emission Scanning Electron Microscopy (FE-SEM), Dynamic Light Scattering (DLS) and X-ray powder diffraction (P-XRD). UV-Vis spectrum showed the highest absorbance at 420 nm. FTIR analysis depicts presence of bond stretching including OH- (3300 cm
), C=N- (2100 cm
) and NH- (1630 cm
) which are attributed in the involvement of phenolics, proteins or nitrogenous compounds in reduction and stabilization of AgNPs. TEM, FE-SEM and DLS analysis revealed the spherical and rod nature of SpNPs and an average size of particles as 37.5 nm. XRD analysis showed the presence of the cubic structure of Ag which confirmed the synthesis of silver nanoparticles. To demonstrate antimicrobial efficacy, we evaluated SpNPs antimicrobial activity against two bacterial pathogens (Escherichia coli (ATCC 11229) and Staphylococcus epidermidis (ATCC 12228)). SpNPs showed a significantly high inhibition for both pathogens and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were found to be 0.39 µg/mL and 0.78 µg/mL for E. coli while 0.19 µg/mL and 0.39 µg/mL for S. epidermidis respectively. Further, Syto 16 staining of bacterial cells provided a supplemental confirmation of the antimicrobial efficacy as the bacterial cells treated with SpNPs stop to fluoresce compared to the untreated bacterial cells. Our highly potent SpNPs will likely have a great potential for many antimicrobial applications including wound healing, water purification, air filtering and other biomedical applications.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Coastal sediments play a fundamental role in processing anthropogenic trace metal inputs. Previous studies have shown that terrestrial organic matter (OM) is a significant vector for trace metal ...transport across the land-to-sea continuum, but little is known about the fate of land-derived metal-OM complexes in coastal sediments. Here, we use a comprehensive set of sediment pore water and solid-phase analyses to investigate how variations in terrestrial OM delivery since the 1950s have influenced trace metal accumulation and diagenesis in a human-impacted boreal estuary in the northern Baltic Sea. A key feature of our dataset is a strong correlation between terrestrial OM deposition and accumulation of metal-OM complexes in the sediments. Based on this strong coupling, we infer that the riverine input of terrestrial metal-OM complexes from the hinterland, followed by flocculation-induced settling in the estuary, effectively modulates sedimentary trace metal sequestration. While part of the trace metal pool associated with these complexes is efficiently recycled in the surface sediments during diagenesis, a substantial fraction is permanently buried as refractory metal-OM complexes or through incorporation into insoluble sulfides, thereby escaping further biological processing. These findings suggest that terrestrial OM input could play a more pivotal role in trace metal processing in coastal environments than hitherto acknowledged.
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•Estuarine trace metal processing was studied using sediment geochemical methods.•Terrestrial organic matter input drives estuarine trace metal accumulation.•Accumulation of terrestrial organic matter and trace metals peaked in the 1970s.•Diagenetic processes transform trace metals into more refractory phases.•Refractory metal-OM complexes comprise a permanent trace metal sink in the estuary.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Metamaterial absorber (MMA) is now attracting significant interest due to its attractive applications, such as thermal detection, sound absorption, detection for explosive, military radar, wavelength ...detector, underwater sound absorption, and various sensor applications that are the vital part of the internet of things. This article proposes a modified square split ring resonator MMA for Ku-band sensing application, where the metamaterial structure is designed on FR-4 substrate material with a dielectric constant of 4.3 and loss tangent of 0.025. Perfect absorption is realized at 14.62 GHz and 16.30 GHz frequency bands, where peak absorption is about 99.99% for both frequency bands. The proposed structure shows 70% of the average absorption bandwidth of 420 MHz (14.42-14.84 GHz) and 480 MHz (16.06-16.54 GHz). The metamaterial property of the proposed structure is investigated for transverse electromagnetic mode (TEM) and achieved negative permittivity, permeability, and refractive index property for each absorption frequency band at 0°, 45°, and 90° polarization angles. Interference theory is also investigated to verify the absorption properties. Moreover, the permittivity sensor application is investigated to verify the sensor performance of the proposed structure. Finally, a comparison with recent works is performed, which shows that the proposed MMA can be a good candidate for Ku-band perfect absorber and sensing applications.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Polygalacturonase (PG) catalyses the hydrolysis of pectin substances and is commonly used in the textile and food industries. Herein, PG was purified from Arabian balsam using three techniques ...(ammonium sulfate precipitation, ion exchange chromatography, and gel filtration) with a recovery of 11.2% and tenfold purification. The molecular weight of the purified PG was estimated to be 75.5 kDa using a Sephadex G-150 column. To improve the stability and reusability of the purified enzyme, a novel method to immobilize PG through calcium alginate-coated polypyrrole/silver nanocomposite was described. The immobilized PG was characterized by FTIR, TGA, SEM, EDX, and Raman spectroscopy. The immobilization efficiency was 84.4%. Excellent long-term storage stability of the immobilized PG was demonstrated with 83% of the initial activity preserved after 60 days. The immobilized PG was highly reusable, showing high activity (91% and 68%) after five and ten cycles. The immobilized PG showed improved stability to temperature and pH relative to that of the free enzyme. The
K
m
and
V
max
were determined to be 0.368 mg/mL and 5.33 µmol/mL for the immobilized PG and 0.667 mg/mL and 7.38 µmol/mL for free PG, respectively. Improved storage stability, catalytic efficiency (
V
max
/
K
m
), and reusability of the immobilized PG make it ideal for biotechnological and industrial applications.
Graphic Abstract
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The quadridentate tetraaza ligand (H 2 L) containing dioxime function groups and its palladium (II) complex PdL were synthesized and structurally characterized by analytical and various spectroscopic ...techniques (MS‐ES, 1 HNMR, FTIR, UV–Vis, and PXRD in addition to SEM and EDX analysis). Processing powder X‐ray diffraction data and DFT calculations coupled with spectroscopic measurements revealed slightly distorted square planar stereochemistry. The anticancer activity of the newly synthesized dioxime palladium (II) complex, PdL, has been studied and the findings of this study emphasize that PdL complex potentially combats cancer by exhibiting diverse cytotoxic impacts. These effects include reduced cell mitosis, decreased metastasis of MDA‐MB‐231 cancer cells, inhibition of topoisomerase II, and induction of apoptotic cell death. In conclusion, the present palladium (II) complex could be a potential therapeutic drug in breast cancer because it can reduce topoisomerase II expression, which is essential in metastasis. This inhibition also reduces the expression of CDK1, which plays an important role in cell cycle regulation.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract Inorganic nitrite, a metabolite of endogenously produced nitric oxide (NO) from NO synthases (NOS), provides the largest endocrine source of directly bioavailable NO. The conversion of ...nitrite to NO occurs mainly through enzymatic reduction, mediated by a range of proteins, including haem-globins, molybdo-flavoproteins, mitochondrial proteins, cytochrome P450 enzymes, and NOS. Such nitrite reduction is particularly favoured under hypoxia, when endogenous formation of NO from NOS is impaired. Under normoxic conditions, the majority of these nitrite reductases also scavenge NO, or diminish its bioavailability via reactive oxygen species (ROS) production, suggesting an intricate balance. Moreover, nitrite, whether produced endogenously, or derived from exogenous nitrite or nitrate administration (including dietary sources via the Nitrate–Nitrite–NO pathway) beneficially modulates many key cardiovascular pathological processes. In this review, we highlight the landmark studies which revealed nitrite's function in biological systems, and inspect its evolving role in cardiovascular protection. Whilst these effects have mainly been ascribed to the activity of one or more nitrite reductases, we also discuss newly-identified mechanisms, including nitrite anhydration, the involvement of s-nitrosothiols, nitro-fatty acids, and direct nitrite normoxic signalling, involving modification of mitochondrial structure and function, and ROS production. This article is part of a Special Issue entitled “Redox Signalling in the Cardiovascular System”.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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