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1.
Curr Microbiol ; 77(9): 2093-2103, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32504323

RESUMEN

Helicobacter pylori is a gram negative, spiral-shaped, and microaerophilic bacteria which can cause life-threatening diseases. It is known that more than 55% of the human population in the world is already infected by this bacterium. The traditional treatment of H. pylori infection consists of a combination of two or more antibiotics. However, H. pylori has evolved to turning its shape from spiral to coccoid form in the presence of antibiotics and this decreases the therapeutic efficacies of conventional antibiotic applications. Resuscitation promoter factor (RPF) is a protein secreted by Micrococcus luteus have significant resuscitation effects on some bacteria especially in the group of viable but non-culturable (VBNC) pathogens. However, there is no study in the literature investigating the resuscitation effects of RPF derived from M. luteus on H. pylori in order to change its form from coccoid to spiral. The purpose of this study is to investigate the resuscitation effect of RPF-containing metabolites isolated from M. luteus on the morphological transformation of H. pylori coccoid forms to spiral forms in order to increase their susceptibilities to antibiotic treatments. Rpf-containing metabolites were primarily obtained from M. luteus culture supernatants. H. pylori was exposed to five different conditions such as prolonged culture, incubation at + 4 °C, incubation at + 22 °C, cultivation in PBS and treatment with kanamycin in order to induce transformations of bacteria to coccoid forms. Induced H.pylori coccoids were characterized by inverted microscope, UV spectrophotometer, SEM imaging, and flow-cytometer. As a result, it was found that the most suitable condition for inducing coccoid forms was cultivation of bacteria with kanamycin. Followingly, different concentrations of RPF-containing metabolites were applied on H. pylori coccoids induced by kanamycin. For the first time in this study, it was determined that the Rpf-containing metabolites obtained from M. luteus demonstrated very high resuscitation effect on kanamycin-induced H. pylori coccoid forms. This new approach for resuscitation of H. pylori coccoids is thought to play an important role in increasing the treatment effectiveness of the conventional antibiotics against the infection.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Antibacterianos/farmacología , Humanos , Micrococcus luteus , Microscopía
2.
J Photochem Photobiol B ; 208: 111902, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32470714

RESUMEN

The present study reports the anticancer activities of Cuminum cyminum L. (Cumin) seed extract, chemically synthetized silver nanoparticles (AgNPs) and biosynthesized silver nanoparticles (Bio-AgNPs) from Cumin seeds on human breast adenocarcinoma cell line (MCF-7) and human breast adenocarcinoma metastatic cell line (AU565). The synthetized nanoparticles were characterized by dynamic light scattering (DLS), UV-visible spectroscopy (UV-Vis), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM). The cytotoxic and anticancer effects of AgNPs and Bio-AgNPs were determined by MTT assay. According to the cytotoxicity analysis, Bio-AgNPs appears to be less toxic against J774 macrophage cells than AgNPs since IC50 values were measured as 0.75 and 1.25 µg/ml for AgNPs and Bio-AgNPs, respectively. On the other hand, Bio-AgNPs demonstrated significant inhibitory effects on human breast cancer cells at non-toxic concentrations such as 0.25 and 0.5 µg/ml. However, at increased concentrations, the lethal effects of AgNPs on breast cancer cells were higher than Bio-AgNPs. When cytotoxic and anticancer characteristics of Cumin extract were investigated, it was established that it did not show any inhibitory effect on J774 cells, while killing the half of MCF-7 cells at investigated concentrations. Interestingly, Cumin extract gave rise to no inhibitory effects against AU565 cells. On the other hand, AgNPs and Bio-AgNPs exhibited considerable anticancer activities on both cell lines. The inhibition percentages of AgNPs on MCF-7 and AU565 cell lines were respectively evaluated as 95% and 97% at the highest concentrations applied (12.5 µg/ml). Similarly, we determined that 87.5% and 96% of MCF-7 and AU565 cells were respectively inhibited when they were exposed to the highest concentrations of Bio-AgNPs. Considering relatively toxic-free features of Bio-AgNPs prepared from Cuminum cyminum L. seed extracts, it can be thought that this formulation will be a pioneer in development of nanotechnology-based new anticancer drug for the treatment of breast cancer in near future.


Asunto(s)
Cuminum/química , Nanopartículas del Metal/química , Extractos Vegetales/química , Plata/química , Antineoplásicos/química , Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cuminum/metabolismo , Femenino , Tecnología Química Verde , Humanos , Nanopartículas del Metal/toxicidad , Semillas/química , Semillas/metabolismo
3.
Expert Rev Anti Infect Ther ; 17(10): 829-840, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31591930

RESUMEN

Introduction: Helicobacter Pylori (H.Pylori) is a pathogen that infects about 50% of the world's population and is known to be responsible for gastroduodenal diseases such as atrophic gastritis, peptic ulcer and stomach cancer. Nowadays, there is no treatment that ensures complete eradication. In addition, resistance to antibiotics used in the current treatment adversely affects the success rates in the fight against infection. Areas covered: This article take attention to treatment approaches using nanoparticles as an alternative to H.Pylori treatment to cope with increased antibiotic resistance. The purpose of this review is to provide an overview of the current limitations and new promising altenatives in treatment of H.Pylori, to highlight the location of nanotechnology to overcome treatment failures, and to emphasize the advantages of using membrane-coated nanoparticles for the first time. Expert opinion: Because of the current problems in the treatment of H.Pylori, there is increasing interest in alternative approaches including nanotechnology. The strong antibacterial effects of metallic nanoparticles, the advantages of polymeric nanoparticles in drug delivery and drug protection, and the prominent properties of membrane-coated nanoparticles in direct targeting demonstrate the significance of nanotechnology in developing new approaches for treatment of H.Pylori infection.


Asunto(s)
Antibacterianos/administración & dosificación , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori/efectos de los fármacos , Animales , Sistemas de Liberación de Medicamentos , Farmacorresistencia Bacteriana , Infecciones por Helicobacter/microbiología , Helicobacter pylori/aislamiento & purificación , Humanos , Nanopartículas , Nanotecnología
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