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1.
J Enzyme Inhib Med Chem ; 39(1): 2311157, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38348846

RESUMO

Novel coumarin derivatives were synthesised and tested for their cytotoxicity against human cancer cells (PC-3 and MDA-MB-231). Compounds 5, 4b, and 4a possessed potent cytotoxic activity against PC-3 cells with IC50 3.56, 8.99, and 10.22 µM, respectively. Compound 4c displayed cytotoxicity more than erlotinib in the MDA-MB-231 cells with IC50 8.5 µM. Moreover, compound 5 exhibited potent inhibitory activity on EFGR with IC50 0.1812 µM, as well as PI3Kß inhibitory activity that was twofold higher than LY294002, suggesting that this compound has a dual EGFR and PI3Kß inhibiting activity. Docking aligns with the in vitro results and sheds light on the molecular mechanisms underlying dual targeting. Furthermore, compound 5 decreased AKT and m-TOR expression in PC-3 cells, showing that it specifically targets these cells via the EGFR/PI3K/Akt/m-TOR signalling pathway. Simultaneously, compound 5 caused cell cycle arrest at S phase and induced activation of both intrinsic and extrinsic apoptotic pathways.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Apoptose , Receptores ErbB/metabolismo , Cumarínicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Proliferação de Células , Relação Estrutura-Atividade , Simulação de Acoplamento Molecular , Estrutura Molecular
2.
Folia Microbiol (Praha) ; 69(1): 221-234, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37691075

RESUMO

Laccase-producing fungus (MY3) was successfully isolated from soil samples collected from Mansoura Governorate, Egypt. This fungal isolate has shown a high laccase production level over other isolated fungi. The identity of this isolate was determined by the molecular technique 18SrRNA as Curvularia lunata MY3. The enzyme purification was performed using ammonium sulfate precipitation followed by Sephacryl S-200 and DEAE-Sepharose column chromatography. The denatured enzyme using SDS-PAGE had a molar mass of 65 kDa. The purified laccase had an optimum temperature at 40 °C for enzyme activity with 57.3 kJ/mol activation energy for 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) oxidation. The enzyme had an optimum pH of 5.0, and it has shown a high stability at the acidic range (4.5 to 5.5). Mn2+ and Mg2+ ions enhanced the enzyme activity, while most of the enzyme activity was inhibited by Hg2+. Some compounds such as 2-mercaptoethanol, L-cysteine, and sodium azide at a concentration of 10 mmol/L had shown a high suppression effect on the enzyme activity. The enzyme strongly oxidized ABTS and syringaldazine and moderately oxidized DMP and guaiacol. The antimicrobial activity of the purified enzyme towards three pathogenic strains (Escherichia coli ATCC-25922, Staphylococcus aureus NRRLB-767, and Candida albicans ATCC-10231) was evaluated for the potential use as an antimicrobial therapeutic enzyme.


Assuntos
Anti-Infecciosos , Compostos Azo , Benzotiazóis , Curvularia , Lacase , Ácidos Sulfônicos , Lacase/metabolismo , Concentração de Íons de Hidrogênio , Temperatura , Estabilidade Enzimática , Especificidade por Substrato
3.
Front Pharmacol ; 13: 1006062, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36313355

RESUMO

Prostate cancer (PCa) ranks as one of the most commonly diagnosed malignancies worldwide. Toxicity, lack of clinical efficacy, and development of resistance phenotypes are the main challenges in the control of prostate malignancies. Notably, castration-resistance prostate cancer (CRPCa) is a highly aggressive and metastatic phenotype of the disease with a poor prognosis and very limited therapeutic options. Herein, we report the isolation and genotypic identification of a soil-derived fungus Aspergillus neoniveus using the PCR-based internal transcribed spacer (ITS) region amplification approach. HPLC/MS investigation of the metabolic profile of the ethyl acetate extract from the fungal biomass revealed tentative identification of forty-five compounds belonging to various chemical classes including γ-butyrolactones, alkaloids, phenolics, and quinoids. Furthermore, the chromatographic purification of microbial extract enabled the identification of nervonic acid methyl ester (1) for the first time from endophytic fungi, as well as acetyl aszonalenin (2), and butyrolactone II (3) for the first time from A. neoniveus. The chemical frameworks of the isolated compounds were identified via extensive spectral analysis including 1 and 2D NMR and MS. The X-ray crystal structure and absolute configuration of acetyl aszonalenin (2) were also determined. Additionally, screening of in vitro anticancer activity of the fungal extract revealed its potential antiproliferative and anti-migratory activities against five different prostate cancer cells (PC3, PC-3M, DU-145, CWR-R1ca, and 22Rv1), including different cells with the castration-resistance phenotype. Moreover, the isolated metabolites significantly inhibited the proliferation, migration, and colonization of human prostate cancer cells at low micromolar levels, thus providing credence for future investigation of these metabolites in relevant anti-prostate cancer animal models. Furthermore, computational target prediction tools identified the cannabinoid G-protein coupled receptors type 1 (CB1) as a potential biological target mediating, at least in part, the anticancer effects of acetylaszonalenin (2). Moreover, molecular modeling and docking studies revealed a favorable binding pose at the CB1 receptor orthosteric ligand pocket aided by multiple polar and hydrophobic interactions with critical amino acids. In conclusion, the Aspergillus neoniveus-derived prenylated indole alkaloid acetylaszonalenin has promising anticancer activity and is amenable to further hit-to-lead optimization for the control of prostate malignancies via modulating CB1 receptors.

4.
World Neurosurg ; 152: e235-e240, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34058357

RESUMO

BACKGROUND: One of the most preventable errors of a surgeon's career is operating on the incorrect surgical site (ICSS). No study in any specialty has ever investigated the incidence of ICSS events in lower-income countries. This study focuses on identifying the occurrence of these events along with an analysis of potential causes leading to these unfortunate events. METHODS: The authors distributed a survey to neurosurgical colleagues from around the world. These surgeons were first asked to identify details about their practice and incidence and personal experience with ICSS in their own careers. At the end of the survey, they responded to questions about their knowledge of safety checklists. RESULTS: In this study there was a 63.4% response rate. When combined with those who participated through various social media platforms, there were 178 responses. The incidence rate for every 10,000 cases performed was found to be 22.8 in the cranial group, 88.6 in the cervical group, and 158.8 in the lumbar procedural group. This study identified that 40% of participants had never learned or experienced the ABCD time-out strategy and that 60% of surgeons did not use intraoperative navigation or imaging in their practices. The error has never been disclosed to the patient in 48% of the ICSS cases. CONCLUSIONS: Due to a lack of application of safety checklist protocol, there is an increased occurrence of ICSS events in lower-income countries. The results of this study demonstrate the necessity of investing time and resources dedicated to avoiding preventable errors.


Assuntos
Países em Desenvolvimento/estatística & dados numéricos , Erros Médicos/estatística & dados numéricos , Procedimentos Neurocirúrgicos/estatística & dados numéricos , Encéfalo/cirurgia , Vértebras Cervicais/cirurgia , Lista de Checagem , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Incidência , Vértebras Lombares/cirurgia , Erros Médicos/prevenção & controle , Neuronavegação , Neurocirurgiões , Cirurgia Assistida por Computador , Inquéritos e Questionários
5.
Food Chem Toxicol ; 141: 111399, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32418920

RESUMO

This study aimed to determine the bioactive compounds of Bacillus sp. MERNA97 extract and to evaluate their efficacy against the oxidative damage, genotoxicity, chromosomal aberration and DNA fragmentation in rats treated with AFB1. Sixty male Sprague-Dawley rats were divided into 6 groups and treated for 6 weeks and included the control group, AFB1-treated group (80 µg/kg b. w), the groups treated with Bacillus extract (BE) at low (2 mg/kg b.w) or high (4 mg/kg b.w) dose and the groups treated with AFB1 plus BE at the two doses. Blood and tissues samples were collected for different assays. The GC-MS results revealed the isolation of 44 compounds belong to different classes. The in vivo results showed that AFB1 disturbs all the biochemical parameters, oxidative stress markers, cytokines gene expression chromosomal aberration and DNA fragmentation along with the histological changes in the liver tissue. BE at the two tested doses induced a significant improvement in all parameters tested and the histological picture in a dose dependent manner. It could be concluded that the extract of Bacillus sp. MERNA97 isolated from the marine environment in the Red Sea is a promise as a source of novel compounds with therapeutically benefits.


Assuntos
Aflatoxina B1/toxicidade , Bacillus/metabolismo , Carcinógenos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Mutagênicos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Venenos/toxicidade , Animais , Biomarcadores/metabolismo , Aberrações Cromossômicas , Citocinas/genética , Relação Dose-Resposta a Droga , Masculino , Ratos , Ratos Sprague-Dawley
6.
Toxicon ; 181: 57-68, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32353570

RESUMO

This study aimed to identify the bioactive compounds of the ethyl acetate extract of Aspergillus niger SH2-EGY using GC-MS and to evaluate their protective role against aflatoxin B1 (AFB1)-induced oxidative stress, genotoxicity and cytotoxicity in rats. Six groups of male Sprague-Dawley rats were treated orally for 4 weeks included the control group, AFB1-treated group (80 µg/kg b.w); fungal extract (FE)-treated groups at low (140) or high dose (280) mg/kg b.w and the groups treated with AFB1 plus FE at the two tested doses. The GC-MS analysis identified 26 compounds. The major compounds found were 1,2,3,4,6-Penta-trimethylsilyl Glucopyranose, Fmoc-L-3-(2-Naphthyl)-alanine, D-(-)-Fructopyranose, pentakis (trimethylsilyl) ether, bis (2-ethylhexyl) phthalate, trimethylsilyl ether-glucitol, and octadecanamide, N-(2- methylpropyl)-N-nitroso. The in vivo results showed that AFB1 significantly increased serum ALT, AST, creatinine, uric acid, urea, cholesterol, triglycerides, LDL, carcinoembryonic antigen, alpha-fetoprotein, interleukin-6, Malondialdehyde, nitric oxide, Bax, caspase-3 and P53 mRNA expression, chromosomal aberrations and DNA fragmentation. It decreased serum TP, albumin, HDL, Bcl-2 mRNA expression, hepatic and renal TAC, SOD and GPx content and induced histological changes in the liver and kidney. FE prevented these disturbances in a dosage-dependent manner. It could be concluded that A. niger SH2-EGY extract is safe a promising agent for pharmaceutical and food industries.


Assuntos
Aflatoxina B1/toxicidade , Antioxidantes/uso terapêutico , Aspergillus niger , Animais , Fragmentação do DNA/efeitos dos fármacos , Inativação Metabólica/efeitos dos fármacos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
7.
Int J Biol Macromol ; 139: 1162-1167, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31415850

RESUMO

This study aims to prepare binary edible films made from carboxymethyl cellulose (CMC) and chitosan biguanidine hydrochloride (CBg) activated with frankincense oil (FO). The interactions between CMC, CBg and FO were confirmed by FTIR. XRD showed that the addition of FO led to decreasing the crystallinity of CMC/CBg films. The water vapour permeability was reduced upon increasing the FO content. The presence of FO made the films brighter and didn't change their transparency as detected from the color measurements. The films exhibited better mechanical properties in the presence of FO as detected from the improved values of both tensile strength and elongation at break. The prepared films exhibited excellent antibacterial activity especially at high content of FO (5%). CMC/CBg/FO films might be used potentially in the production of edible films due to their excellent physical and antibacterial properties.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Carboximetilcelulose Sódica/química , Quitosana/química , Franquincenso/química , Óleos Voláteis/química , Bacillus subtilis/efeitos dos fármacos , Teste de Materiais , Permeabilidade , Vapor , Streptococcus pneumoniae/efeitos dos fármacos , Resistência à Tração
8.
Int J Biol Macromol ; 117: 179-188, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29807082

RESUMO

The cellulose-based antimicrobial hydrogel was prepared from seed and husk cellulosic fibers of olive industry residues by load silver nanoparticles (AgNPs) onto grafted acrylamide monomer (Am) cellulosic fibers. The grafting approach was the free radical mechanism by utilizing ceric ammonium nitrate (CAN) as initiator in aqueous medium and N,N methylene bisacrylamide (MBAm) as a cross linker. The effect of different grafting conditions on the properties of produced hydrogels has been studied by determining the grafting parameters, i.e. concentration of Am, MBAm, grafting time and temperature to optimize grafting yield (G %), grafting efficiency (GE %), and swelling %. Characterizations of the obtained hydrogels were performed through monitoring swelling behavior, FTIR spectroscopy, SEM, and EDX. AgNPs were grown into the prepared hydrogel. Hydrogel/AgNPs were characterized by FT-IR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The hydrogel loaded AgNPs exhibit high efficient antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Celulose/química , Celulose/farmacologia , Hidrogéis/química , Resíduos Industriais , Azeite de Oliva/química , Candida albicans/efeitos dos fármacos , Cinética , Nanopartículas Metálicas/química , Pseudomonas aeruginosa/efeitos dos fármacos , Prata/química , Staphylococcus aureus/efeitos dos fármacos , Temperatura
9.
Curr Microbiol ; 74(11): 1294-1300, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28752341

RESUMO

Cancer is a leading cause of death in several countries. In the search for new anticancer drugs, marine organisms have played an important role in the discovery of lead compounds and the development of new pharmaceuticals for their wide diversity of chemical structures and biological activities. In the present study, the cytotoxicity on colorectal cancer cells HCT116 exerted by marine fungus Aspergillus sp. 2C1-EGY extracts associated with the soft coral Sinularia sp. was investigated; the sub-fractions Fr 2c and Fr 2d had significantly high cytotoxic activity (88 and 85%, respectively). Moreover, the major hexadecanoic, octadecanoic, and octadecenoic acids as well as their methyl esters were isolated. GC/MS analysis revealed the identification of 46 major and minor compounds, from which 19 saturated and unsaturated fatty acids and eight fatty acid esters were identified.


Assuntos
Antozoários/microbiologia , Antineoplásicos/farmacologia , Aspergillus/química , Produtos Biológicos/farmacologia , Animais , Antineoplásicos/química , Aspergillus/classificação , Aspergillus/genética , Produtos Biológicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Espectroscopia de Ressonância Magnética , Filogenia , RNA Ribossômico 18S/genética
10.
Curr Microbiol ; 74(1): 6-13, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27743105

RESUMO

Marine organisms have been considered as the richest sources of novel bioactive metabolites, which can be used for pharmaceutical purposes. In the last years, the interest for marine microorganisms has grown for their enormous biodiversity and for the evidence that many novel compounds isolated from marine invertebrates are really synthesized by their associated bacteria. Nevertheless, the discovery of a chemical communication Quorum sensing (QS) between bacterial cells and between bacteria and host has gained the researchers to expand the aim of their study toward the role of bacteria associated with marine invertebrates, such as marine sponge. In the present paper, we report the evaluation of biological activities of different extracts of bacteria Vibrio sp. and Bacillus sp. associated with marine sponges Dysidea avara and Ircinia variabilis, respectively. Moreover, we evaluated the biological activities of some diketopiperazines (DKPs), previously isolated, and able to activate QS mechanism. The results showed that all extracts, fractions, and DKPs showed low scavenging activity against DPPH and superoxide anion, low cytotoxic and anti-tyrosinase activities, but no antimicrobial and acetylcholinesterase inhibitory activities. One DKP [cyclo-(trans-4-hydroxy-L-prolyl-L-leucine)] has the highest α-glucosidase inhibitory activity even than the standard acarbose.


Assuntos
Bactérias/química , Dicetopiperazinas/farmacologia , Poríferos/microbiologia , Animais , Antioxidantes/química , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biodiversidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dicetopiperazinas/análise , Dicetopiperazinas/metabolismo , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Glucosidases/análise , Glucosidases/antagonistas & inibidores , Humanos
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