jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Mohamed A. Morsy | Snehal Patel | Pranali Parmar | Jignasa Savjani | Mahmoud Kandeel | Anroop B. Nair | Sabah H. Akrawi | Mahmoud El‐Daly
Source: Indian Journal of Pharmaceutical Education and Research (article, 2022-09-01)
Field: Chemistry — Organic Chemistry

Functional Role of Novel Anthranilic Acid Derivatives as Anti-inflammatory Agents The discovery of new cyclooxygenase (COX) inhibitors with high efficacy and safety would greatly aid in developing anti-inflammatory drugs. This study evaluated the anti-inflammatory activity and the expected side effect of two synthesized anthranilic acid derivatives (JS-3 and JS-4). Materials and Methods: The COX selectivity of compounds was assessed in a whole blood assay. The results were confirmed by molecular docking studies. In vivo anti-inflammatory activity was tested in complete Freund's adjuvant (CFA)-induced rheumatoid arthritis (RA) in rats. The safety profile was determined by administering a dose three times the therapeutic dose. Results: In vitro COX-2 selectivity of JS-4 was higher than JS-3 (13.70 vs. 5.56). Docking studies supported the higher selectivity of both derivatives against COX-2 than mefenamic acid. Treatment of CFA-arthritic rats with both compounds showed significant (P < 0.01) decreases in paw volume, paw thickness, arthritic index, and inflammatory parameters such as rheumatoid factor, interleukin (IL)-1, IL-6, prostaglandin (PG) E 2 , PGI 2 , and TXB 2 compared to untreated RA animals. JS-3 and JS-4 improved knee joint histopathology and protected against RA-induced pathological changes: splenomegaly, thymomegaly, and cardiomyopathy. Both derivatives produced minimal effects on liver and renal functions, without any ulcerogenic effects. Conclusion: These results suggest that JS-4 is a potential and safe candidate for managing RA without renal, liver, gastrointestinal, or cardiovascular toxicity. Rheumatoid arthritis ; Mefenamic acid ; Pharmacology ; Anthranilic acid ; Arthritis ; In vivo ; Medicine ; Toxicity ; Piroxicam ; Chemistry ; Immunology ; Internal medicine ; Biochemistry ; Pathology Synthesis and biological activity ; Pharmacological Effects of Natural Compounds ; Natural product bioactivities and synthesis
Authors: Maria Saadeh
Source: theses.fr (ABES) (preprint, 2022-01-21)
Field: Materials Science — Materials Chemistry

Use of organic semiconductors to improve the flexoelectric response of flexible polymers Flexoelectricity, which is induced by a strain gradient, is a mechanical-electrical effect that applies to all insulating or semiconducting materials. The work consisted of studying the flexoelectric response of various conjugated semiconductor polymers deposited in thin filmson flexible devices. In a first part, it was demonstrated for the first time in poly (3- hexylthiophene) (P3HT) and poly (3,4 ethylenedioxythiophene) (PEDOT) a flexoelectric response which turned out to be ten times greater than those observed in insulating polymers. The use of polythiophene-electrolytes constructed with cationic alkyl chains grafted onto thiophene rings has made it possible to achieve flexoelectric coefficients even ten times greater than those of P3HT. .In a second part, poly (3,4-ethylenedioxythiophene) polystyrenesulfonate (PEDOT: PSS), was the subject of an in-depth study to bring out the different parameters allowing to obtain high possible flexoelectric coefficients. Thus, from PEDOT: PSS solutions with a formulation of 1:6 with top gold electrodes, very high flexoelectric coefficients were obatined reaching values close to semiconductor metal oxides were obtained. Subsequently, simple treatments such as the addition of xylitol further amplified the flexoelectric current generated by the strain gradient in these soft and flexible devices. It is also shown that for devices based on PEDOT: PSS, the high polarizability which induces flexoelectricity is due to both electronic and ionic effect Organic semiconductor ; Semiconductor ; Materials science ; Polymer ; Nanotechnology ; Optoelectronics ; Engineering physics ; Composite material ; Engineering Nonlocal and gradient elasticity in micro/nano structures ; Vibration and Dynamic Analysis ; Advanced Materials and Mechanics
Authors: Agrawal Lokesh | Vimal Sunil Kumar | Barzaghi Paolo | Takashi Shiga | Terenzio Marco
Source: Institutional Repositories DataBase (IRDB) (article, 2022-09-28)
Field: Materials Science — Biomaterials

Biodegradable and electrically conductive melanin‐Poly (3‐hydroxybutyrate) 3D fibrous scaffolds for neural tissue engineering applications Due to the severity of peripheral nerve and spinal cord injuries, treatment options for patients are limited. In this context, biomaterials designed to promote regeneration and reinstate the lost function are being explored. Such biomaterials should be able to mimic the biological, chemical, and physical cues of the extracellular matrix for maximum effectiveness as therapeutic agents. Development of biomaterials with desirable physical, chemical, and electrical properties, however, has proven challenging. Here, we propose a novel biomaterial formulation achieved by blending the pigment melanin and the natural polymer Poly (3-hydroxybutyrate). Physio-chemical measurements of electrospun fibers revealed a feature rich surface nano-topography, a semiconducting-nature and brain-tissue-like poroviscoelastic properties. Resulting fibers improved cell adhesion and growth of mouse sensory and motor neurons, without any observable toxicity. Further, the presence of polar functional groups positively affected the kinetics of fibers degradation at a pH (∼7.4) comparable to that of body fluids. Thus, melanin-PHB blended scaffolds were found to be physio-chemically, electrically, and biologically compatible with neural tissues and could be used as a regenerative modality for neural tissue injuries. Biomaterial ; Regeneration (biology) ; Tissue engineering ; Neural tissue engineering ; Extracellular matrix ; Adhesion ; Neural Prosthesis ; Self-healing hydrogels Silk-based biomaterials and applications ; Nerve injury and regeneration ; Electrospun Nanofibers in Biomedical Applications
Authors: Alexander B. Draganov
Source: Digital Archive @ GSU (article, 2022-04-12)
Field: Chemistry — Organic Chemistry

Novel Anticancer Agents That Upregulate p53 and A New Type of Neighbouring Group Assisted Click Reactions In the everlasting battle against cancer the development of drugs targeting new therapeutic pathways is of crucial importance. In the attempt to develop new anticancer agents we have synthesized a library of anthraquinone compounds that show selectivity against leukemia. Mechanistic evaluation of the lead compound reveal that this class of compounds achieve their effects through inhibition of MDM2-MDM4 heterodimer and upregulation of the tumor suppressor p53. Computer aided rational design resulted in the development of a number of compounds with activities in the nanomolar range against various cancer cells. Analysis of the physicochemical properties of selected compounds allowed for their evaluation as potential drug candidates. The successful development of non-toxic formulations permits for the further in vivo investigation of the compounds. Click reactions have found wide spread applications in sensing, materials chemistry, bioconjugation, and biolabeling. A number of very useful click reactions have been discovered, which allow for various applications. In bioconjugation applications, the ability to conduct a secondary conjugation will be very useful in, e.g., protein pull down and binding site identification. Along this line, we describe a neighboring group-assisted facile condensation between an aldehyde and a vicinal aminothiol moiety, leading to the formation of benzothiazoles. The conversion is completed within 5 minutes at low micromolar concentrations at ambient temperature. The facile reaction was attributed to the presence of a neighboring boronic acid, which functions as an intramolecular Lewis Acid in catalyzing the reaction. The boronic acid group is compatible with most functional groups in biomolecules and yet can also be used for further functionalization via a large number of well-known coupling reactions. Group (periodic table) ; Computer science ; Type (biology) ; Chemistry ; Biology Click Chemistry and Applications ; Advanced biosensing and bioanalysis techniques ; Chemical Synthesis and Analysis
Authors: Bin Huang | Hao Kang | Changwei Zhang | Xiao‐Li Zhao | Xueliang Shi | Hai‐Bo Yang
Source: Research Square (preprint, 2022-05-04)
Field: Chemistry — Organic Chemistry

De novo design of a new open-shell nitrogen-centered diradicaloid with tunable stimuli-responsive electronic properties and diradical character Abstract In this study, we present the de novo design of a new open-shell nitrogen-centered diradicaloid which can reversibly respond to multiple stimuli and display the tunable diradical character and chemo-physical properties. 1a was successfully synthesized through a simple and high-yielding two-step synthetic strategy. Both experimental and calculated results indicated that 1a displayed an open-shell singlet ground state with small singlet-triplet energy gap (Δ E S−T = -2.311 kcal mol − 1 ) and a modest diradical character ( y 0 = 0.55). Interestingly, 1a was demonstrated to undergo reversible Lewis acid-base reaction with both Lewis acid and Brønsted acid to form acid-base adducts due to its intrinsic Lewis basicity. The formation of Lewis acid-base adduct was proven to effectively tune the ground-state electronic structures of 1a as well as its diradical character and spin density distributions. Based on this, we succeeded in devising a photoresponsive system based on 1a and a commercially available photoacid merocyanine (MEH). We believe that our studies including the entirely new molecular design methodology and the newly found stimuli-responsive organic diradicaloid system will open up a new way to develop new diradicaloids with tunable properties and even intelligent-responsive diradicaloid-based materials. Diradical ; Character (mathematics) ; Shell (structure) ; Open shell ; Nitrogen ; Materials science ; Nanotechnology ; Chemistry ; Physics ; Mathematics ; Organic chemistry ; Quantum mechanics Synthesis and Properties of Aromatic Compounds ; Porphyrin and Phthalocyanine Chemistry ; Photochromic and Fluorescence Chemistry
Authors: Anastasia Skonta | Elena Gkantzou | Konstantinos Spyrou | Stamatia Spyrou | Angeliki C. Polydera | Dimitrios Gournis | Haralambos Stamatis
Source: Catalysis Research (article, 2022-10-08)
Field: Materials Science — Biomaterials

3D Printed Polylactic Acid (PLA) Well Plates for Enzyme Inhibition Studies: The Case of Pancreatic Lipase 3D printed PLA has already been demonstrated for several biotechnological applications, including enzymes immobilization. The prerequisites for an efficient screening assay include using small volumes of reagents, low cost, and rapid screening of large numbers of compounds and extracts. Hence, assays based on microtiter plates are predominant. Thus, designing and fabricating scaffolds on a similar scale, which could serve as immobilization carriers, and their recruitment in inhibitors screening studies is of great significance, adding both enzyme stability and reuse potentiality of the biocatalytic system in assay merits. In this work, pancreatic lipase was immobilized on 3D-printed PLA microwells for enzyme inhibitor screening. XPS analysis demonstrated the successful modification of the PLA scaffolds. The immobilized enzyme displayed high levels of operational, thermal, and storage stability under the tested conditions. The IC&lt;sub&gt;50&lt;/sub&gt; values for PPL inhibition were calculated for Orlistat, a model lipase inhibitor, and olive leaf extract, a promising natural compound. This is the first study reporting the use of 3D-printed PLA wells with an immobilized enzyme for inhibitor screening assay. Lipase ; Polylactic acid ; Enzyme ; Pancreatic lipase ; Enzyme inhibition ; Immobilized enzyme biodegradable polymer synthesis and properties ; 3D Printing in Biomedical Research ; Enzyme Catalysis and Immobilization
Authors: Ruyu Jia | Richard T. Bradshaw | Valeria Calvaresi | Argyris Politis
Source: bioRxiv (Cold Spring Harbor Laboratory) (preprint, 2022-07-11)
Field: Materials Science — Materials Chemistry

Integrative HDX-MS enables quantification of the conformational landscape of the sugar transporter XylE Abstract A yet unresolved challenge in structural biology is to quantify conformational states of proteins underpinning function. This challenge is particularly acute for membrane proteins owing to the difficulties in stabilising them for i n vitro studies. To address this challenge, we present here an integrative strategy that combines hydrogen-deuterium exchange mass spectrometry (HDX-MS) with ensemble modelling. We benchmark our strategy on wild type and mutant conformers of XylE, a prototypical member of the ubiquitous Major Facilitator Superfamily (MFS) of transporters. Next, we apply our strategy to quantify conformational ensembles of XylE embedded in different lipid environments and identify key lipid contacts that modulate protein conformations. Further application of our integrative strategy to substrate-bound and inhibitor-bound ensembles, allowed us to unravel protein-ligand interactions contributing to the alternating access mechanism of secondary transport in atomistic detail. Overall, our study highlights the potential of integrative HDX-MS modelling to capture, accurately quantify and subsequently visualise co-populated states of membrane proteins in association with mutations and diverse substrates and inhibitors. For Table of Content Only Major facilitator superfamily ; Chemistry ; Hydrogen–deuterium exchange ; Conformational ensembles ; Computational biology ; Lipid bilayer ; Conformational isomerism ; Transporter ; Biophysics ; Protein structure ; Biochemistry ; Membrane ; Biology ; Mass spectrometry ; Gene Enzyme Structure and Function ; Metabolomics and Mass Spectrometry Studies ; Mass Spectrometry Techniques and Applications
Authors: Aman Singh Tomar | Neelam Khan | Neetesh Kumar Jain
Source: International Journal of Medical Sciences and Pharma Research (article, 2022-06-15)
Field: Chemistry — Organic Chemistry

Synthesis, Characterization and Anti-Diabetic Activity of Novel 2-Substituted Indole Derivatives Accordingly, the nitrogen in each nucleus, viz. 2-phenylindole, carbazole, phenothiazine and dibenzylamine, was planned to be alkylated applying several N-­alkylating conditions, using either bromochloropropane or bromochlorobutane to give alkylated products with chloro-group available at the end of 2-carbon and 3-carbon chain. The chloro-group can then thought be utilized in reaction with p-hydroxyacetophenone to form ethereal linkage, by applying conditions of Williamson’s ether synthesis. The acetyl group present in the products could then easily be converted into indole ring using conditions of Fischer’s-indole synthesis.57 Further, it was planned to confirm the structures of synthesized compounds using spectral and elemental analysis, apart from simple laboratory techniques like physical constants and classical chemical tests. Keywords: Indole, 2-Phenylindole, Carbazole, Diabetes, Anti-diabetic activity. Indole test ; Phenothiazine ; Carbazole ; Alkylation ; Chemistry ; Ether ; Ring (chemistry) ; Carbon fibers ; Combinatorial chemistry ; Organic chemistry ; Stereochemistry ; Materials science ; Catalysis Synthesis and biological activity ; Synthesis and Reactions of Organic Compounds ; Synthesis and Biological Evaluation
Authors: Lin Wang | Liu Liu | Yongfeng Liu | Xiaotong Zhou | Fumin Chi
Source: Research Square (preprint, 2022-04-27)
Field: Chemistry — Spectroscopy

Proteomic Analysis and Comparison of Protein in Tibetan pork and Ordinary pork using TMT-coupled LC-MS/MS Abstract The objective of this study was to comparatively analyze protein of Tibetan pork and ordinary pork using liquid chromatography tandem-mass spectrometry (LC − MS/MS) combined with tandem mass tag (TMT) labeling. The results showed that 2447 proteins were identified and 249 proteins were significantly changed including 165 significantly up-regulated and 84 significantly down-regulated proteins. The more abundant proteins of Tibetan pork included NADH dehydrogenase, Pyruvate dehydrogenase E1, Very long-chain specific acyl-CoA dehydrogenase, ATPase inhibitor and Cytochrome b-c1 complex subunit 7, which were up-regulated. A Gene Ontology (GO) analysis showed that these proteins mainly participated in biological process, the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and the Clusters of Orthologous Groups of proteins (COG) analysis showed that they may be related to energy metabolism and conversion pathway of metabolism process. According to the protein-protein interaction (PPI) analysis, these proteins interacted significantly. This study revealed the Tibetan pork’s advantages in the aspects of energy metabolism compared with ordinary pork at the protein levels. KEGG ; Gene ontology ; Chemistry ; NADH dehydrogenase ; Tandem mass tag ; Biochemistry ; Protein subunit ; Proteomics ; Lipid metabolism ; Tandem mass spectrometry ; Metabolism ; Gene ; Mass spectrometry ; Chromatography ; Quantitative proteomics ; Gene expression Advanced Proteomics Techniques and Applications ; Metabolomics and Mass Spectrometry Studies ; Molecular Biology Techniques and Applications
Authors: Samira Khandan | Issa Yavari
Source: Research Square (preprint, 2022-11-04)
Field: Chemistry — Organic Chemistry

Formation of bis-spiropyrrolidines from isatin, secondary amins, and alkylidene Meldrum’s acids Abstract Abstract A synthesis of stable bis-spiropyrrolidines from isatin, secondary amines, and alkylidene Meldrum’s acids in MeCN in 75–95% yield is described. The antioxidant properties and antimicrobial abilities of the synthesized compounds are investigated. For this purpose, the radical scavenging activities of four derivatives were studied by radical trapping of diphenylpicrylhydrazine and ferric reduction power experiments. Disk diffusion test on Gram-positive and Gram-negative bacteria employed to investigate antibacterial activities of five derivatives. Isatin ; Yield (engineering) ; Chemistry ; Antimicrobial ; Ferric ; Organic chemistry ; Antioxidant ; Bacteria ; Primary (astronomy) ; Nuclear chemistry ; Medicinal chemistry ; Materials science ; Biology Free Radicals and Antioxidants ; Organic Chemistry Cycloaddition Reactions ; Synthesis and Characterization of Pyrroles
Authors: LIQIONG LIU
Source: FARMACIA (article, 2022-06-26)
Field: Chemistry — Organic Chemistry

ANTITUMOR EFFECTS OF ANLOTINIB HYDROCHLORIDE ON HUMAN PANCREATIC CANCER CELLS Anlotinib hydrochloride (AL3818), a new multi-kinase inhibitor, has shown promising antitumor efficiency in several advanced malignancies.However, data on AL3818 use for pancreatic cancer are still limited.This study aimed to investigate the antitumor activity of AL3818 and its underlying molecular mechanisms in human pancreatic cancer cells.The human pancreatic cancer cell line PANC-1 was exposed in vitro to increasing concentrations of AL3818 treatment (0.1, 0.5, 1, 2, or 5 µmol/L).The antiproliferative effect of AL3818 was determined by 3-(4 5-dimethyl-2-thiazolyl)-2 5-diphenyl-2-H-tetrazolium bromide (MTT) assay.Cell cycle alterations and apoptosis rates were evaluated by flow cytometry, while expression of Tolllike receptor 4 (TLR-4), Nuclear factor kappa B (NF-κB), Vascular endothelial growth factor (VEGF), survivin, and Bax proteins were detected by Western blot.Our experimental data demonstrated a dose-dependent decrease in the proliferation of PANC-1 cells following treatment with AL3818.AL3818 efficiently induced G2/M phase cell cycle arrest and promoted cell apoptosis in a dose-dependent manner.In addition, expression levels of TLR-4, NF-κB, VEGF, and survivin proteins were decreased, while upregulation of Bax levels was achieved under AL3818 treatment.Our results suggested that AL3818 could interfere with PANC-1 cell proliferation and apoptosis in vitro.Treatment was also found to induce G2/M phase cell cycle arrest, possibly associated with upregulation of Bax protein and downregulation of VEGF, survivin, and TLR-4/NF-κB signalling pathway.Further research is clearly warranted to confirm these findings. RezumatClorhidratul de anlotinib (AL3818), un nou inhibitor de multi-kinază, a dovedit o eficiență antitumorală promițătoare în mai multe tumori maligne avansate.Acest studiu a avut ca scop investigarea activității antitumorale a AL3818 și a mecanismelor moleculare care stau la baza acesteia, în celulele cancerului pancreatic uman.Datele noastre experimentale au demonstrat o scădere doză-dependentă a proliferării celulelor PANC-1 în urma tratamentului.AL3818 a indus în mod eficient oprirea ciclului celular în faza G2/M și a determinat apoptoza celulară într-o manieră doză-dependentă.În plus, expresia proteinelor TLR-4, NF-κB, VEGF și a survivinelor a fost redusă, în timp ce nivelul Bax a crescut sub tratamentul cu AL3818.Rezultatele noastre sugerează că AL3818 ar putea interfera cu proliferarea și apoptoza celulelor PANC-1 in vitro.S-a constatat, de asemenea, că tratamentul a indus stoparea ciclului celular în faza G2/M, posibil asociat cu o creștere a proteinei Bax și o scădere a VEGF, a nivelului de survivină și a căii de semnalizare TLR-4/NF-κB. Pancreatic cancer ; Hydrochloride ; Cancer research ; Cancer ; Pharmacology ; Chemistry ; Medicine ; Internal medicine ; Biochemistry Synthesis and biological activity ; Cancer, Hypoxia, and Metabolism ; Retinoids in leukemia and cellular processes
Authors: 祥通 下村 | Yoshimichi Shimomura | 和宣 井川 | Kazunobu Igawa | 俊輔 佐々木 | Shunsuke Sasaki | 頼太 後関 | Raita Goseki | 玄一 小西 | Gen‐ichi Konishi
Source: Institutional Repositories DataBase (IRDB) (article, 2022-07-01)
Field: Materials Science — Materials Chemistry

Flexible Alkylene Bridges as a Tool To Engineer Crystal Distyrylbenzene Structures Enabling Highly Fluorescent Monomeric Emission To design ultrabright fluorescent solid dyes, a crystal engineering strategy that enables monomeric emission by blocking intermolecular electronic interactions is required. We introduced propylene moieties to distyrylbenzene (DSB) as bridges between the phenyl rings either side of its C=C bonds. The bridged DSB derivatives formed compact crystals that emit colors similar to those of the same molecules in dilute solution, with high quantum yields. The introduction of flexible seven-membered rings to the DSB core produced moderate distortion and steric hindrance in the DSB π-plane. However, owing to this strategy, it was possible to control the molecular arrangement with almost no decrease in the crystal density, and intermolecular electronic interactions were suppressed. The bridged DSB crystal structure differs from other DSB derivative structures; thus, bridging affords access to novel crystalline systems. This design strategy has important implications in many fields and is more effective than the conventional photofunctional molecular crystal design strategies. Intermolecular force ; Steric effects ; Monomer ; Crystal (programming language) ; Fluorescence ; Crystal engineering ; Molecule Luminescence and Fluorescent Materials ; Crystallography and molecular interactions ; Supramolecular Chemistry and Complexes