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1.
Microsc Res Tech ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38450823

RESUMO

This contribution insight on the cytotoxic and anticancer activities and molecular mechanism of phyto-reduced silver nanoparticles (AgNPs) in MCF-7 breast cancer cell lines. A simple, entirely green synthesis process was optimized for the phyto-reduction of AgNP (~12.7 nm) using aqueous leaf extracts of Indigofera heterantha. The structural and vibrational properties of biosynthesized AgNPs were extensively characterized using UV-Vis spectrophotometer, x-ray diffraction (XRD), dynamic light scattering (DLS), and Fourier transform Infrared spectroscopy (FTIR), while their shape and morphology was studied through scanning electron microscopy (SEM). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell viability assay indicates concentration dependent inhibition with IC50 , 27.93 ± 2.10 µg/mL against MCF-7 cells and 294.38 ± 3.87 µg/mL against L929 cells. The manifested anticancer mechanism in MCF-7 cells was extensively studied using Acridine orange/ethidium bromide (AO/EB), 4',6-diamidino-2-phenylindole (DAPI) and Annexin-V/propedium iodide fluorescence microscopic assays. The level of reactive oxygen species (ROS) was measured using DCFH-DA fluorescent spectroscopy. Overall, the results show that AgNPs exhibit cytotoxic and apoptotic effect on breast cancer MCF-7 cells by damaging membrane integrity and nuclear fragmentation due to oxidative stress generated by elevated level of ROS. RESEARCH HIGHLIGHTS: Biomimetic synthesis of nano dimension size silver nanoparticles (AgNPs). Characterization of AgNPs through UV-Vis, DLS, XRD, FTIR, and SEM. Cytotoxic and anticancer effects of the biosynthesized AgNPs in L929 fibroblast cells and MCF7 breast cancer respectively. Determination of morphological, and nuclear changes triggered by AgNPs in MCF 7 breast cancer cells using fluorescent microscopy and flow cytometry. Apoptosis induction by AgNPs in cancer cells through oxidative stress generated by reactive oxygen species (ROS).

2.
Infect Genet Evol ; 108: 105399, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36584905

RESUMO

Bats remains as reservoirs for highly contagious and pathogenic viral families including the Coronaviridae, Filoviridae, Paramyxoviruses, and Rhabdoviridae. Spill over of viral species (SARS-CoV, MERS-CoV & SARS-CoV2) from bats (as a possible potential reservoirs) have recently caused worst outbreaks. Early detection of viral species of pandemic potential in bats is of great importance. We detected beta coronaviruses in the studied bats population (positive samples from Rousettus leschenaultia) and performed the evolutionary analysis, amino acid sequence alignment, and analysed the 3-Dimentional protein structure. We detected the coronaviruses for the first time in bats from Pakistan. Our analysis based on RdRp partial gene sequencing suggest that the studied viral strains are closely related to MERS-CoV-like viruses as they exhibit close structure similarities (with few substitutions) and also observed a substitution in highly conserved SDD in the palm subdomain of motif C to ADD, when compared with earlier reported viral strains. It could be concluded from our study that coronaviruses are circulating among the bat's population in Pakistan. Based on the current findings, we suggest large scale screening procedures of bat virome across the country to detect potential pathogenic viral species.


Assuntos
COVID-19 , Quirópteros , Coronaviridae , Coronavírus da Síndrome Respiratória do Oriente Médio , Vírus , Humanos , Animais , RNA Viral , Paquistão/epidemiologia , Filogenia , COVID-19/genética , SARS-CoV-2/genética , Coronaviridae/genética , Vírus/genética , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Genoma Viral
3.
PLoS One ; 17(12): e0277825, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36520861

RESUMO

Endophytic bacteria are the source of novel bioactive compounds, used as therapeutic agent. Molecular docking is a computational technique use frequently, to find novel drugs targets and drugs-receptors interactions. The current study was designed to isolate and identify endophytic bacteria for the extraction of bioactive compounds. Further, to characterized extracts and to explore compounds interactions with bacterial cell wall and outer membrane synthesizing proteins. Endophytes were identified using 16s rRNA amplification technique. For bioactive compounds, solvent extraction method was followed and characterized further through GC-MS analysis. To find targets and drugs-receptors interactions, molecular docking studies and biological assays were performed. The isolated endophytes belong to five different genera namely Enterobacter, Bacillus, Erwinia, Stenotrophomonas and Pantoea. In case of antibacterial assay Stenotrophomonas maltophilia extract showed significant inhibitory zones (15.11±0.11mm and 11.3±0.16) against Staphylococcus caseolyticus and Acinetobacter baumanni, with MIC 33.3 and 50µg/mL respectively. Among the characterized fifty compounds, from endophytic bacteria "antibacterial compound" N-(5-benzyl-10b-hydroxy-2-methyl-3,6-dioxooctahydro-8H-oxazolo[3,2-α] pyrrolo[2,1c] pyrazin-2-yl)-7-methyl2,3,3a,3a1,6,6a,7,8,9,10,10a,10b-dodecahydro-1H-4λ2-indolo[4,3-fg]quinoline-9-carboxamide of bacteria Stenotrophomonas maltophilia were an excellent binder with MurF ligase active site, with binding energy of -10.2 kcal/mol. Extracts of endophytic bacteria composed of various pharmacologically active ingredients such as antibacterial compounds. Molecular docking studies provide important information regarding drug-receptor interaction, thus can be used in novel drug discovery.


Assuntos
Bactérias , Endófitos , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/metabolismo , Simulação de Acoplamento Molecular , Bactérias/genética , Endófitos/metabolismo , Antibacterianos/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/metabolismo
4.
J Biomol Struct Dyn ; 40(8): 3753-3768, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-33246391

RESUMO

Hepatitis C virus (HCV), which infected 71 million worldwide and about 5%-6% are from Pakistan, is an ssRNA virus, responsible for end-stage liver disease. To date, no effective therapy is available to cure this disease. Hence, it is important to study the most prevalent genotypes infecting human population and design novel vaccine or small molecule inhibitors to control the infections associated with HCV. Therefore, in this study clinical samples (n = 35; HCV-3a) from HCV patients were subjected to Sanger sequencing method. The sequencing of the core gene, which is generally considered as conserved, involved in the detection, quantitation and genotyping of HCV was performed. Multiple mutations, that is, R46C, R70Q, L91C, G60E, N/S105A, P108A, N110I, S116V, G90S, A77G and G145R that could be linked with response to antiviral therapies were detected. Phylogenetic analysis suggests emerging viral isolates are circulating in Pakistan. Using ab initio modelling technique, we predicted the 3D structure of core protein and subjected to molecular dynamics simulation to extract the most stable conformation of the structure for further analysis. Immunoinformatic approaches were used to propose a multi-epitopes vaccine against HCV by using core protein. The vaccine constructs consist of nine CTL and three HTL epitopes joined by different linkers were docked against the two reported Toll-like receptors (TLR-3 and TLR-8). Docking of vaccine construct with TLR-3 and TLR-8 shows proper binding and in silico expression of the vaccine resulted in a CAI value of 0.93. These analyses suggest that specific immune responses may be produced by the proposed vaccine.Communicated by Ramaswamy H. Sarma.


Assuntos
Hepatite C , Vacinas , Substituição de Aminoácidos , Epitopos de Linfócito T , Fluprednisolona/análogos & derivados , Hepacivirus/genética , Hepatite C/prevenção & controle , Humanos , Paquistão , Filogenia , Receptor 3 Toll-Like/genética , Receptor 3 Toll-Like/uso terapêutico , Receptor 8 Toll-Like/genética , Vacinas/uso terapêutico
5.
Braz. J. Pharm. Sci. (Online) ; 58: e20989, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1420394

RESUMO

Abstract Plants from genus Ephedra are commonly used by the Chinese people as folk medicine for treatment of various diseases. The current study was designed to explore the ethno-pharmacological based pharmacological potentials of Ephedra intermedia Schrenk & C.A. Mey. (E. intermedia). Plant aerial parts were extracted using ten solvent systems with increasing order of polarity. Samples were analyzed for total phenolic and flavonoid contents, HPLC-DAD analysis, antibacterial, antifungal, HepG2 cell line cytotoxicity, hemolysis and antioxidant potentials following standard procedures. Highest percent extract recovery was observed in Eth+WT (25.55 % w/w) solvent system. Flavonoid and phenolic contents were higher in chloroform and Met+WT fractions respectively. Considerable antibacterial activity was shown by Eth+Met extract against B. subtilis and K. pneumonia (MIC of 11.1μg/mL for each). Eth extract exhibited high antifungal activity against A. fumigates (15±0.31 mm DIZ). Met+WT extract showed significant cytotoxicity against HepG2 cell lines with IC50 of 13.51+0.69 μg/mL. Substantial free radical scavenging activity (74.9%) was observed for Met+Eth extract. In the current study, several solvent systems were used for more effective extraction of fractions and can be useful in the isolation of phytochemicals. Various fractions exhibited considerable antimicrobial, antioxidant and cytotoxic potentials. Biological potentials of E. intermedia signify its potential uses in microbial, cancer and degenerative disorders and thus warrant further detailed studies.

6.
Oxid Med Cell Longev ; 2021: 3095514, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34326915

RESUMO

The genus Viburnum (Adoxaceae, Dipsacales) is of scientific interest due to the chemical components and diverse biological activities found across species of the genus, which includes more than 230 species of evergreen, semievergreen, or deciduous shrubs and small trees. Although frequently used as an ornament, the Viburnum species show biological properties with health-promoting effects. Fruits, flowers, and barks of certain species are used for pharmaceutical purposes or as cooking ingredients, hence containing biochemical compounds with health-promoting activity such are carotenoids, polyphenols, and flavonoids. However, its taxonomical determination is difficult, due to its wide distribution and frequent hybridizations; therefore, an objective classification would allow us to understand its biological activity based on its phytochemical components. More than sixty phytochemical compounds have been reported, where vibsanin-type diterpenes and their derivatives are the most prevalent. Leaves and twigs of V. dilatatum contain the largest number of phytochemicals among the genus. Through preclinical evidence, this study provides insight regarding antioxidant, antibacterial, anti-inflammatory, cytotoxic, and anticancer activities of genus Viburnum.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Viburnum/química , Antineoplásicos Fitogênicos/farmacologia , Humanos
7.
Antonie Van Leeuwenhoek ; 114(10): 1497-1516, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34324106

RESUMO

Biosynthesis of silver nanoparticles (AgNPs) from marine actinobacteria offers a promising avenue for exploring bacterial extracts as reducing and stabilizing agents. We report extracellular extracts of Rhodococcus rhodochrous (MOSEL-ME29) and Streptomyces sp. (MOSEL-ME28), identified by 16S rRNA gene sequencing for synthesis of AgNPs. Ultrafine silver nanoparticles were biosynthesized using the extracts of R. rhodochrous and Streptomyces sp. and their possible therapeutic applications were studied. The physicochemical properties of nanoparticles were established by HR-SEM/TEM, SAED, UV-Vis, EDS, XRD, and FTIR. UV-Vis spectra displayed characteristic absorption at 430 nm and 412 nm for AgNPs from Streptomyces sp. (S-AgNPs) and Rhodococcus sp. (R-AgNPs), respectively. HR-SEM/TEM, XRD, EDS analysis confirmed the spherical shape, crystalline nature, and elemental formation of silver. Crystallite or grain size was deduced as 5.52 nm for R-AgNPs and 35 nm for S-AgNPs. Zeta-potential indicated electrostatic negative charge for AgNPs, while FTIR revealed the presence of diverse functional groups. Disc diffusion assay indicated the broad-spectrum antibacterial potential of S-AgNPs with the maximum inhibition of B. subtilis while R-AgNPs revealed potency against P. aeruginosa at 10 µg/mL concentration. Biogenic AgNPs revealed antileishmanial activity and the IC50 was calculated as 164 µg/mL and 184 µg/mL for R-AgNPs and S-AgNPs respectively. Similarly, the R-AgNPs and S-AgNPs revealed anti-cancer potential against HepG2 and the IC50 was calculated as 49 µg/mL and 69 µg/mL for R-AgNPs and S-AgNPs, respectively. Moreover, the antioxidant activity showed significant results. MTT assay on RD cells, L20B cells, and Hep-2C indicated intensification in viability by reducing the concentration of R-AgNPs and S-AgNPs. The R-AgNPs and S-AgNPs inhibited sabin-like poliovirus (1TCID50 infection in RD cells). Furthermore, hemocompatibility at low concentrations has been confirmed. Hence, it is concluded that biogenic-AgNPs has the potential to be used in diverse biological applications and that the marine actinobacteria are an excellent resource for fabrication of AgNPs.


Assuntos
Actinobacteria , Nanopartículas Metálicas , Actinobacteria/genética , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Extratos Vegetais , RNA Ribossômico 16S/genética , Rhodococcus , Prata/farmacologia
8.
Microsc Res Tech ; 84(12): 3087-3103, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34310797

RESUMO

We report a facile, green and precursor-based comparative study on the biosynthesis of zinc oxide (ZnO) nanoparticles (NPs) using anticancerous Fagonia indica as effective chelating agent. Biosynthesis was carried out using zinc sulfate and zinc acetate as precursor salts to make ZnOS and ZnOA NPs under similar experimental conditions which were characterized extensively for physical and biological properties. Scherrer equation deduced a mean crystallite size of ~23.4 nm for ZnOA NPs and ~41 nm for ZnOS NPs. The nature of the NPs was compared using UV, diffuse reflectance spectra, Fourier transform infrared spectroscopy, thermogravimetric analysis-DTA, selected area electron diffraction, EDS, zeta potential, high resolution (HR)-SEM, and HR-TEM. Detailed in vitro pharmacognostic activities revealed a significant therapeutic potential for ZnOA and ZnOS . Potential antimicrobial activities for the NPs and their nanocosmeceutical formulations are reported. ZnOA NPs were more cytotoxic to Leishmania tropica as compared to ZnOS . Significant antioxidant and protein kinase inhibition was obtained. The hemolytic assay indicated a hemocompatible nature of both ZnOA and ZnOS NPs. Catalytic degradation of crystal violet dye (CVD) by NPs was examined under different parameters (light, dark, UV). Furthermore, sonophotocatalytic degradation of CVD was also studied. Our results suggested that precursor can have a significant effect on the physical, biological, and catalytic properties of the NPs. In future, we recommend different other in vitro, in vivo biological activities, and mechanistic studies of these as-synthesized NPs.


Assuntos
Nanopartículas , Óxido de Zinco , Antioxidantes , Extratos Vegetais/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Antonie Van Leeuwenhoek ; 114(8): 1165-1179, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33945066

RESUMO

Protection of crop plants from phytopathogens through endophytic bacteria is a newly emerged area of biocontrol. In this study, endophytic bacteria were isolated from the rhizosphere of Cannabis sativa. Based on initial antimicrobial screening, three (03) bacteria Serratia marcescens MOSEL-w2, Enterobacter cloacae MOSEL-w7, and Paenibacillus MOSEL-w13 were selected. Antimicrobial assays of these selected bacteria against Phytophthora parasitica revealed that E. cloacae MOSEL-w7 and Paenibacillus sp. MOSEL-w13 possessed strong activity against P. parasitica. All these bacterial extracts showed strong inhibition against P. parasitica at different concentrations (4-400 µg mL-1). P. parasitica hyphae treated with ethyl acetate extract of E. cloacae MOSEL-w7 resulted in severe growth abnormalities compared to control. The extracts were further evaluated for in vivo detached-leaf assay against P. parasitica on the wild type tobacco. Application of 1% ethyl acetate bacterial extract of S. marcescens MOSEL-w2, E. cloacae MOSEL-w7, and Paenibacillus sp. MOSEL-w13 reduced P. parasitica induced lesion sizes and lesion frequencies by 60-80%. HPLC based fractions of each extract also showed bioactivity against P. parasitica. A total of 24 compounds were found in the S. marcescens MOSEL-w2, 15 compounds in E. cloacae MOSEL-w7 and 20 compounds found in Paenibacillus sp. MOSEL-w13. LC-MS/MS analyses showed different bioactive compounds in the bacterial extracts such as Cotinine (alkylpyrrolidine), L-tryptophan, L-lysine, L-Dopa, and L-ornithine. These results suggest that S. marcescens MOSEL-w2, E. cloacae MOSEL-w7, and Paenibacillus MOSEL-w13 are a source of bioactive metabolites and could be used in combination with other biocontrol agents, with other modes of action for controlling diseases caused by Phytophthora in crops. They could be a clue for the broad-spectrum biopesticides for agriculturally significant crops.


Assuntos
Cannabis , Paenibacillus , Phytophthora , Cromatografia Líquida , Doenças das Plantas , Espectrometria de Massas em Tandem
10.
Int J Infect Dis ; 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34000421

RESUMO

OBJECTIVE: In current study we performed sequencing of palm domain of HCV-NS5B gene, its ancestral analysis along with amino acids substitution analysis. These analysis were done to find the molecular basis of the viral resistance against Sofosbuvir drug. METHODS: Blood samples from individuals with chronic Hepatitis C infection that were resistant to Sofosbuvir were collected. The samples were processed for their molecular characterization that included RNA extraction, Complementary DNA (cDNA) synthesize, nested PCR, gel elution, Sequencing, ancestral and 3D structure analysis. RESULTS: Evolutionary analysis revealed that current study sequences (QAU-01, QAU-02) clustered with a previously studied sequence, KY971494.1. Moreover, we reports multiple novel amino acid substitutions in the palm domain of NS5B gene such as Ile116Val, Asn117Gly, Glu246Ala, Val252Ala, Glu258Gln, Cys262Leu, Ser269Arg, Ala272Thr, Ile293Leu, Lys304Arg, Asn307Gly, Ala338Val and Arg345Gly in our query sequence (QAU-01). At 246 and 269 position in (QAU-02), no substitution was observed. CONCLUSIONS: We have noticed that the current sequences are relatively emerging and could have been originated from aforementioned sequence recently. Based on the current results, we suggests that these substitutions could be associated with structural or functional impairment of protein and could also be may be considered as resistance associated substitutions (RAS) to Sofosbuvir drug.

12.
Arch Microbiol ; 203(5): 2475-2489, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33675371

RESUMO

In a preliminary plant-based microbiome study, diverse bacterial taxa were identified from different medicinal plants using 16S rRNA gene sequencing. Based on initial antimicrobial screening, eight (8) bacterial endophytes in six (6) different genera, Streptomyces, Pseudomonas, Enterobacter, Bacillus, Arthrobacter, and Delftia, from four important medicinal plants Dodonaea viscosa, Fagonia indica, Caralluma tuberculata, and Calendula arvensis were selected for further analyses. Antimicrobial assays revealed that Pseudomonas taiwanensis MOSEL-RD23 has strong anti-Phytophthora activity. Volatiles produced by P. taiwanensis MOSEL-RD23and Bacillus flexus MOSEL-MIC5 inhibited the growth of Phytophthora parasitica by more than 80%. Ethyl acetate extracts of Streptomyces alboniger MOSEL-RD3, P. taiwanensis MOSEL-RD23, Enterobacter hormaechei MOSEL-FLS1, and Bacillus tequilensis MOSEL-FLS3, and Delftia lacustris MB322 displayed high potency against P. parasitica. All these bacterial extracts showed strong inhibition of more than 80% inhibition in vitro against P. parasitica at different concentrations (4-400 µg/mL). Bacterial extracts showing strong antimicrobial activity were selected for bioactivity-driven fractionation and showed anti-Phytophthoral activity in multiple fractions and different peaks observed in UV-Vis spectroscopy. In the detached-leaf assay against P. parasitica on tobacco, 1% ethyl acetate bacterial extract of S. alboniger MOSEL-RD3, P. taiwanensis MOSEL-RD23, E. hormaechei MOSEL-FLS1, B. tequilensis MOSEL-FLS3, and D. lacustris MB322 reduced lesion sizes and lesion frequencies caused by P. parasitica by 68 to 81%. Overall, P. taiwanensis MOSEL-RD23 showed positive activities for all the assays. Analyzing the potential of bacterial endophytes as biological control agents can potentially lead to the formulation of broad-spectrum biopesticides for the sustainable production of crops.


Assuntos
Agentes de Controle Biológico/farmacologia , Microbiota , Phytophthora/efeitos dos fármacos , Plantas Medicinais/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Agentes de Controle Biológico/isolamento & purificação , Agentes de Controle Biológico/metabolismo , Endófitos/classificação , Endófitos/genética , Endófitos/isolamento & purificação , Endófitos/metabolismo , Testes de Sensibilidade Parasitária , Phytophthora/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Plantas Medicinais/classificação , RNA Ribossômico 16S/genética
13.
Arch Microbiol ; 203(5): 2491-2500, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33677635

RESUMO

Genome analysis gives important insights into the biosynthetic potential of marine actinobacteria. The genomes of two marine actinomycetes Brevibacterium luteolum MOSEL-ME10a and Cellulosimicrobium funkei MOSEL-ME6 were sequenced to identify the biosynthetic gene clusters (BGCs). Additionally, anti-proliferative, antioxidant, and enzyme inhibitory activities were studied in vitro. We report a total genome size of 2.77 Mb with GC content of 67.8% and 6.81 Mb with GC content of 69% for Brevibacterium sp. MOSEL-ME10a and Cellulosimicrobium sp. MOSEL-ME6, respectively. Biosynthetic gene clusters (BGCs) encoding different classes of natural products were predicted including terpenes, peptides, siderophores, ectoines, and bacteriocins. The bioactivity potential of crude extracts derived from these strains was evaluated. Notable anti-proliferative activity was observed against HepG2 cell line (hepatocellular carcinoma) with an IC50 value of 182 µg/mL for Brevibacterium sp. MOSEL-ME10a. Furthermore, antioxidant activity was assessed with IC50 values of 48.91 µg/mL and 102.5 µg/mL for Brevibacterium sp. MOSEL-ME10a and Cellulosimicrobium sp. MOSEL-ME6, respectively. Protein kinase inhibition potential was observed only for Brevibacterium sp. MOSEL-ME10a. Our study also reports lower amylase enzyme inhibition potential for both strains. Moreover, both crude extracts showed only slight-to-no toxic effect on erythrocytes at 400 µg/mL and below, indicating erythrocyte membrane stability. Our data present the genomic features revealing biosynthetic potential of marine actinobacteria as well as biological activities found in vitro.


Assuntos
Actinobacteria/genética , Actinobacteria/metabolismo , Brevibacterium/genética , Brevibacterium/metabolismo , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Produtos Biológicos/química , Produtos Biológicos/metabolismo , Produtos Biológicos/farmacologia , Genoma Bacteriano/genética , Humanos , Família Multigênica , Filogenia , Análise de Sequência de DNA
14.
J Biomol Struct Dyn ; 39(11): 4133-4147, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32567498

RESUMO

Biosynthesis has emerged as an exciting interface for assembling multifunctional metal oxide nanoparticles for diverse medicinal applications. Herein, biogenic nickel oxide (NiO-NPs) is synthesized by using floral extracts of Callistemon viminalis (C. viminalis) as a low cost, ecofriendly reducing and stabilizing agent. NiO-NPs were annealed at 300 °C, 400 °C and 500 °C while their physiochemical properties were established by HR-SEM/TEM, UV, XRD, FTIR, EDS, SAED and SQUID techniques. Particle size of NiO-NPs decreased with increase in annealing temperatures. Magnetization curves indicated superparamagnetic behavior of the biogenic NiO-NPs at 300 K. Highly crystalline NiO-NPs obtained after annealing at 500 °C were used for biomedical applications. The anti-leishmanial activity on Leishmania tropica promastigotes (KMH-23) and anticancer activity on HepG2 (RCB1648) revealed excellent inhibition potential with IC50 of 37.21 µg/mL and 47 µg/mL, respectively. Significant antibacterial effect was observed against Klebsiella pneumonia and Proteus vulgaris with MIC's of 12.5 µg/mL each. Acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and α-glucosidase inhibitory potential were comparable with positive control drugs. Moderate antioxidant activities were observed. NiO-NPs were observed to be hemolytic (30%) at higher dose (1000 µg/mL). Overall, NiO-NPs revealed a multifunctional nature that can be explored for diverse biomedical applications.Communicated by Ramaswamy H. Sarma.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia
15.
Int J Equity Health ; 19(1): 182, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33059674

RESUMO

COVID-19 which started in Wuhan, China and swiftly expanded geographically worldwide, including to Low to Middle Income Countries (LMICs). This in turn raised numerous ethical concerns in preparedness, knowledge sharing, intellectual property rights, environmental health together with the serious constraints regarding readiness of health care systems in LMICs to respond to this enormous public health crisis. From the restrictions on public freedom and burgeoning socio-economic impacts to the rationing of scarce medical resources, the spread of COVID-19 is an extraordinary ethical dilemma for resource constrained nations with less developed health and research systems. In the current crisis, scientific knowledge and technology has an important role to play in effective response. Emergency preparedness is a shared responsibility of all countries with a moral obligation to support each other. This review discusses the ethical concerns regarding the national capacities and response strategies in LMICs to deal with the COVID-19 pandemic as well as the deep link between the environment and the increasing risk of pandemics.


Assuntos
Infecções por Coronavirus/prevenção & controle , Países em Desenvolvimento , Meio Ambiente , Ética , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , COVID-19 , Infecções por Coronavirus/epidemiologia , Previsões , Humanos , Pneumonia Viral/epidemiologia
16.
Oxid Med Cell Longev ; 2020: 1215395, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33082906

RESUMO

Silver nanoparticles are among the most significant diagnostic and therapeutic agents in the field of nanomedicines. In the current study, the green chemistry approach was made to optimize a cost-effective synthesis protocol for silver nanoparticles from the aqueous extract of the important anticancer plant Fagonia indica. We investigated the anticancer potential and possible involvement of AgNPs in apoptosis. The biosynthesized AgNPs are stable (zeta potential, -16.3 mV) and spherical with a crystal size range from 10 to 60 nm. The MTT cell viability assay shows concentration-dependent inhibition of the growth of Michigan Cancer Foundation-7 (MCF-7) cells (IC50, 12.35 µg/mL). In addition, the fluorescent microscopic analysis shows activation of caspases 3 and 9 by AgNPs that cause morphological changes (AO/EB assay) in the cell membrane and cause nuclear condensation (DAPI assay) that eventually lead to apoptotic cell death (Annexin V/PI assay). It was also observed that AgNPs generate reactive oxygen species (ROS) that modulate oxidative stress in MCF-7 cells. This is the first study that reports the synthesis of a silver nanoparticle mediated by Fagonia indica extract and evaluation of the cellular and molecular mechanism of apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 9/metabolismo , Nanopartículas Metálicas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Prata/química , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Sobrevivência Celular/efeitos dos fármacos , Feminino , Química Verde , Humanos , Células MCF-7 , Nanopartículas Metálicas/química , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Zygophyllaceae/química , Zygophyllaceae/metabolismo
18.
Nanomedicine (Lond) ; 15(17): 1653-1669, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32669064

RESUMO

Aim: The biosynthesis of chromium oxide nanoparticles (Cr2O3 NPs), using Hyphaene thebaica as a bioreductant, for assessment of their potential nanomedicinal applications. Materials & methods: Biosynthesized Cr2O3 NPs were characterized by x-ray diffraction, Fourier-transform infrared spectroscopy, energy dispersive x-ray spectroscopy, scanning and transmission electron microscopy, selected area electron diffraction, UV-Vis spectroscopy and ζ-potential measurement. In vitro assays were used to assess the biological properties of Cr2O3 NPs. Results: Nanoparticles with size approximately 25-38 nm were obtained with a characteristic Cr-O vibration at 417 cm-1. A broad spectrum antimicrobial potential and antioxidant nature is reported. Slight inhibition of polio virus and biocompatibility at low doses was observed. Conclusion: We conclude a multifunctional nature of biogenic Cr2O3 NPs.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Extratos Vegetais , Antibacterianos , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
19.
Mater Sci Eng C Mater Biol Appl ; 112: 110890, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32409045

RESUMO

Maghemite (Fe2O3-NPs) nanoparticles were synthesized by a convenient, green and cost effective method using aqueous fruit extracts of Hyphaene thebaica. Different techniques like FTIR, XRD, UV-Vis, Raman, HR-TEM, EDS. SAED, Zeta potential were used to establish the nature of Fe2O3-NPs, while the therapeutic properties were studied using different biological assays including antiviral, antibacterial, antifungal, antioxidant and enzyme inhibition assays. XRD pattern revealed sharp peaks and a crystalline nature of Fe2O3-NPs. HR-TEM revealed quasi-spherical and cuboidal morphologies, while the particle size in ~10 nm. FTIR indicated a sharp peak centered at ~444 cm-1 which is the characteristic FeO band vibration. SAED pattern indicated the crystalline nature while EDS also confirmed the synthesis of Fe2O3 NPs. Zeta potential was obtained in different solvents and physiological buffers indicating highest value in water (-26.5 mV) and lowest in DMSO (-15.8 mV). Tested bacterial strains, Bacillus subtilis was found to be inhibited significantly. Aspergillus flavus appeared to be susceptible to all of the tested concentration of Fe2O3 NPs. Maximum 40.78% FRSA was obtained at 400 µg/mL. Cell culture based studies on RD cells and L20B cells indicated reduction in viability of cells with increase concentration of Fe2O3 NPs. Moderate inhibition of polio virus-1 and polio virus-2 was observed, after culturing the virus in the L20B cells. Excellent Protein Kinase (PK) inhibition was revealed. Hemolytic potential and cytotoxic potential was indicated to be dose dependent. In conclusion, the present report for the first time reports the synthesis of Fe2O3 NPs from H. thebaica fruits and reveals their biomedical potential including antiviral potential.


Assuntos
Arecaceae/química , Nanopartículas Magnéticas de Óxido de Ferro/química , Extratos Vegetais/química , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Antivirais/síntese química , Antivirais/química , Antivirais/farmacologia , Arecaceae/metabolismo , Aspergillus flavus/efeitos dos fármacos , Bacillus subtilis/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Frutas/química , Frutas/metabolismo , Química Verde , Hemólise/efeitos dos fármacos , Humanos , Nanopartículas Magnéticas de Óxido de Ferro/toxicidade , Oxirredução , Tamanho da Partícula , Poliovirus/efeitos dos fármacos , Poliovirus/fisiologia
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