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1.
Front Bioeng Biotechnol ; 9: 745099, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34778226

RESUMO

One of the antibiotics used to treat infections is streptomycin sulfate that inhibits both Gram-negative and -positive bacteria. Nanoparticles are suitable carriers for the direct delivery and release of drug agents to infected locations. Niosomes are one of the new drug delivery systems that have received much attention today due to their excellent biofilm penetration property and controlled release. In this study, niosomes containing streptomycin sulfate were prepared by using the thin layer hydration method and optimized based on the size, polydispersity index (PDI), and encapsulation efficiency (EE%) characteristics. It was found that the Span 60-to-Tween 60 ratio of 1.5 and the surfactant-to-cholesterol ratio of 1.02 led to an optimum formulation with a minimum of size, low PDI, and maximum of EE of 97.8 nm, 0.27, and 86.7%, respectively. The drug release investigation showed that 50.0 ± 1.2% of streptomycin sulfate was released from the niosome in 24 h and reached 66.4 ± 1.3% by the end of 72 h. Two-month stability studies at 25° and 4°C showed more acceptable stability of samples kept at 4°C. Consequently, antimicrobial and anti-biofilm activities of streptomycin sulfate-loaded niosomes against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa were found significantly higher than those of free drug, and the minimum inhibitory concentration values decreased 4- to 8-fold. Furthermore, niosome-encapsulated streptomycin up to 1,500 µg/ml exhibited negligible cytotoxicity against the human foreskin fibroblasts cell line, whereas the free drug exhibited slight cytotoxicity at this concentration. Desired physical characteristics and low toxicity of niosomal nano-carriers containing streptomycin sulfate made them a demanded candidate for the treatment of current bacterial infections and biofilms.

2.
AMB Express ; 11(1): 61, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33900505

RESUMO

The current study evaluated the anti-cancer properties of bio-functionalized silver nanoparticles fabricated by Juniperus chinensis leaf extracts. The nanoparticles were characterized by scanning electron microscopy, transmission electron microscopy, UV-visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, dynamic light scattering, Zeta potential and X-ray spectroscopy. Further, this study elucidated the cellular and molecular mechanisms of nanoparticles for anti-proliferative and apoptotic effects on human lung cancer cells (A549) and compared them with commercial drug cisplatin. The size of the spherical nanoparticle was 12.96 nm with negative zeta potential. Up-regulation of caspase 3,9 and p53, Annexin V-FITC/PI, DAPI staining, and ROS production indicated the remarkable apoptotic effect of AgNPs compared to cisplatin. Moreover, down-regulation of MMP2/MMP9 scratch and matrigel assays revealed anti-metastatic properties of AgNPs. Cell cycle analysis and downregulation of cyclin D1 indicated cancer cell cessation in the G0/G1 phase. Overall, the results revealed that the green-synthetized AgNPs had anti-metastasis and anti-proliferation effects on lung cancer cells in comparison to cisplatin with lower side effects on the normal cell line.

3.
Pharmaceuticals (Basel) ; 15(1)2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-35056063

RESUMO

Breast cancer is one of the most prevalent causes of cancer mortality in women. In order to increase patient prognosis and survival rates, new technologies are urgently required to deliver therapeutics in a more effective and efficient manner. Niosome nanoparticles have been recently employed as therapeutic platforms capable of loading and carrying drugs within their core for both mono and combination therapy. Here, niosome-based nanoscale carriers were investigated as a targeted delivery system for breast cancer therapy. The platform developed consists of niosomes loaded with letrozole and cyclophosphamide (NLC) and surface-functionalized with a folic-acid-targeting moiety (NLCPFA). Drug release from the formulated particles exhibited pH-sensitive properties in which the niosome showed low and high release in physiological and cancerous conditions, respectively. The results revealed a synergic effect in cytotoxicity by co-loading letrozole and cyclophosphamide with an efficacy increment in NLCPFA use in comparison with NLC. The NLCPFA resulted in the greatest drug internalization compared to the non-targeted formulation and the free drug. Additionally, downregulation of cyclin-D, cyclin-E, MMP-2, and MMP-9 and upregulating the expression of caspase-3 and caspase-9 genes were observed more prominently in the nanoformulation (particularly for NLCPFA) compared to the free drug. This exciting data indicated that niosome-based nanocarriers containing letrozole and cyclophosphamide with controlled release could be a promising platform for drug delivery with potential in breast cancer therapy.

4.
J Gastrointest Cancer ; 52(1): 130-137, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31997281

RESUMO

BACKGROUND: The most common chronic bacterial infection is Helicobacter pylori. The connection between chronic H. pylori infection and gastric cancer is recognized. The early detection of gastric cancer improves survival. miRNAs regulate gene expression in eukaryotes by inhibiting mRNA translocation or degradation. The objective of this study was to compare the expression of miRNA-17-3p and miRNA-17-5p genes in gastric cancer patients with Helicobacter pylori infection. METHODS: Herein, 30 isolates were identified as H. pylori based on urease test, and 30 and 12 cases were isolated from gastric cancer patients and non-Helicobacter pylori cases as control, respectively. A peripheral blood sample was collected from patients. Analysis of total mRNA extracts from peripheral blood samples, for gene expression changes (miRNA-17-3p and miRNA-17-5p) by quantitative real-time polymerase chain reaction (qRT-PCR), was done. RESULTS: As said by the results, p values showed that expression levels of miRNA-17-3p and miRNA-17-5p were significantly higher in H. pylori-positive GC patients and H. pylori-positive non-GC patients with comparing by healthy controls. So, there was no significant difference between expression levels of miRNA-17-3p and miRNA-17-5p in H. pylori-positive GC patients and H. pylori-positive non-GC patients. CONCLUSION: Considering our results, the high expression of miRNA-17-3p and miRNA-17-5p has a direct relationship with increased cell proliferation, inhibition of tumor cell apoptosis and tumor angiogenesis, in addition to miRNAs play an important role as biomarkers in helping for detection of the patient by H. pylori infection to become cancerous. Therefore, it can be used to make specific diagnostic kits and to treat patients.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinogênese/genética , Infecções por Helicobacter/patologia , MicroRNAs/metabolismo , Neoplasias Gástricas/genética , Apoptose/genética , Biomarcadores Tumorais/análise , Estudos de Casos e Controles , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/microbiologia , Helicobacter pylori/isolamento & purificação , Helicobacter pylori/patogenicidade , Humanos , Masculino , MicroRNAs/análise , Pessoa de Meia-Idade , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/patologia
5.
Microb Drug Resist ; 27(2): 247-257, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32635796

RESUMO

Background: Klebsiella pneumoniae is currently considered as an immediate threat to human health due to its various multidrug efflux pumps. Microbially synthesized silver nanoparticles (AgNPs) are an attractive and eco-friendly approach to prevent antibiotic resistance in bacteria. In the present study, we compared the inhibitory effect of both commercial and green AgNPs by Bifidobacterium bifidum on OxqAB efflux pump genes in ciprofloxacin-resistant strains of K. pneumoniae. Materials and Methods: AgNPs were characterized by ultraviolet-visible spectrophotometer, Fourier transform infrared spectroscopy, X-ray diffraction, zeta potential, transmission electron microscopy, and scanning electron microscopy. Antibiogram was used to identify resistant isolates and the effect of the biosynthesized AgNPs against OxqAB efflux pump strains was assessed by the minimum inhibitory concentration (MIC) method. The expression levels of oxqAB genes were evaluated using real-time polymerase chain reaction (PCR) followed by exposure to subMICs of the AgNPs. Results: PCR results showed that 25 strains had OxqAB efflux pump and the MIC method indicated that AgNPs had an inhibitory effect on all resistant strains with OxqAB efflux pump. The efficacy of the synthetic nanoparticles was assessed by comparing the antiefflux pump activity with commercial AgNPs. In ciprofloxacin-resistant isolates, the oxqAB genes expression levels reduced in the subMIC of both AgNPs, whereas biosynthesized AgNPs had greater bactericidal effects compared with the commercial AgNPs. Conclusions: Efflux pumps could be an attractive target for our biosynthesized AgNPs. The oxqAB genes expression levels reduced in subMIC of both AgNPs, whereas biosynthesized AgNPs had greater bactericidal effects than the commercial AgNPs.


Assuntos
Antibacterianos/farmacologia , Bifidobacterium bifidum/genética , Expressão Gênica/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Nanopartículas Metálicas/administração & dosagem , Prata/farmacologia , Ciprofloxacina/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Expressão Gênica/genética , Humanos , Testes de Sensibilidade Microbiana/métodos
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