RESUMO
Four new species [Ln(dipicNH2)3]3- (Ln = LaIII, EuIII, GdIII, TbIII), with the ligand dipicNH22- (dipic = dipicolinato), were synthesized. Incubation of the EuIII complex with glioma NG97 and pancreatic cancer PANC1 cells showed that it penetrates the cell membrane and can be used to image the cells, while also being moderately cytotoxic.
Assuntos
Complexos de Coordenação/análise , Complexos de Coordenação/química , Európio/química , Corantes Fluorescentes/análise , Corantes Fluorescentes/química , Glioma/diagnóstico por imagem , Imagem Óptica , Neoplasias Pancreáticas/diagnóstico por imagem , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/farmacologia , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/farmacologia , Humanos , Medições Luminescentes , Camundongos , Células NIH 3T3RESUMO
Nanostructured materials have been widely studied concerning their potential biomedical applications, primarily to selectively carry specific drugs or molecules within a tissue or organ. In this context, boron nitride nanotubes (BNNTs) have generated considerable interest in the scientific community because of their unique properties, presenting good chemical inertness and high thermal stability. Among the many applications proposed for BNNTs in the biomedical field in recent years, the most important include their use as biosensors, nanovectors for the delivery of proteins, drugs, and genes. In the present study, BNNTs were synthesized, purified, and functionalized with glycol chitosan through a chemical process, yielding the BNNT-GC. The size of BNNT-GC was reduced using an ultrasound probe. Two samples with different sizes were selected for in vitro assays. The nanostructures were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), thermal analysis (TGA), and dynamic light scattering (DLS). The in vitro assays MTT and neutral red (NR) were performed with NIH-3T3 and A549 cell lines and demonstrated that this material is not cytotoxic. Furthermore, the BNNT-GC was applied in gene transfection of plasmid pIRES containing a gene region that express a green fluorescent protein (GFP) in NIH-3T3 and A549 cell lines. The gene transfection was characterized by fluorescent protein produced in the cells and pictured by fluorescent microscopy. Our results suggest that BNNT-GC has moderate stability and presents great potential as a gene carrier agent in nonviral-based therapy, with low cytotoxicity and good transfection efficiency.
Assuntos
Compostos de Boro/farmacologia , Quitosana/farmacologia , Células Eucarióticas/metabolismo , Nanotubos/química , Transfecção/métodos , Animais , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Difusão Dinâmica da Luz , Células Eucarióticas/efeitos dos fármacos , Humanos , Camundongos , Células NIH 3T3 , Nanotubos/ultraestrutura , Plasmídeos/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , TermogravimetriaRESUMO
Graphene and carbon nanotube nanocomposite (GCN) was synthesised and applied in gene transfection of pIRES plasmid conjugated with green fluorescent protein (GFP) in NIH-3T3 and NG97 cell lines. The tips of the multi-walled carbon nanotubes (MWCNTs) were exfoliated by oxygen plasma etching, which is also known to attach oxygen content groups on the MWCNT surfaces, changing their hydrophobicity. The nanocomposite was characterised by high resolution scanning electron microscopy; energy-dispersive X-ray, Fourier transform infrared and Raman spectroscopies, as well as zeta potential and particle size analyses using dynamic light scattering. BET adsorption isotherms showed the GCN to have an effective surface area of 38.5m(2)/g. The GCN and pIRES plasmid conjugated with the GFP gene, forming π-stacking when dispersed in water by magnetic stirring, resulting in a helical wrap. The measured zeta potential confirmed that the plasmid was connected to the nanocomposite. The NIH-3T3 and NG97 cell lines could phagocytize this wrap. The gene transfection was characterised by fluorescent protein produced in the cells and pictured by fluorescent microscopy. Before application, we studied GCN cell viability in NIH-3T3 and NG97 line cells using both MTT and Neutral Red uptake assays. Our results suggest that GCN has moderate stability behaviour as colloid solution and has great potential as a gene carrier agent in non-viral based therapy, with low cytotoxicity and good transfection efficiency.
Assuntos
Grafite/química , Nanocompostos/química , Nanotubos de Carbono/química , Transfecção , Células 3T3 , Adsorção , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Proteínas de Fluorescência Verde , Humanos , Magnetismo , Camundongos , Microscopia Eletrônica de Varredura , ÁguaRESUMO
Shigella spp are Gram-negative, anaerobic facultative, non-motile, and non-sporulated bacilli of the Enterobacteriaceae family responsible for "Shigellosis" or bacillary dysentery, an important cause of worldwide morbidity and mortality. However, despite this, there are very few epidemiological studies about this bacterium in Brazil. We studied the antibiotic resistance profiles and the clonal structure of 60 Shigella strains (30 S. flexneri and 30 S. sonnei) isolated from shigellosis cases in different cities within the metropolitan area of Campinas, State of São Paulo, Brazil. We used the following well-characterized molecular techniques: enterobacterial repetitive intergenic consensus, repetitive extragenic palindromic, and double-repetitive element-polymerase chain reaction to characterize the bacteria. Also, the antibiotic resistance of the strains was determined by the diffusion disk method. Many strains of S. flexneri and S. sonnei were found to be multi-resistant. S. flexneri strains were resistant to ampicillin in 83.3% of cases, chloramphenicol in 70.0%, streptomycin in 86.7%, sulfamethoxazole in 80.0%, and tetracycline in 80.0%, while a smaller number of strains were resistant to cephalothin (3.3%) and sulfazotrim (10.0%). S. sonnei strains were mainly resistant to sulfamethoxazole (100.0%) and tetracycline (96.7%) and, to a lesser extent, to ampicillin (6.7%) and streptomycin (26.7%). Polymerase chain reaction-based typing supported the existence of specific clones responsible for the shigellosis cases in the different cities and there was evidence of transmission between cities. This clonal structure would probably be the result of selection for virulence and resistance phenotypes. These data indicate that the human sanitary conditions of the cities investigated should be improved.
Assuntos
Antibacterianos/farmacologia , Disenteria Bacilar/microbiologia , Shigella flexneri/efeitos dos fármacos , Shigella sonnei/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Criança , Pré-Escolar , Farmacorresistência Bacteriana/genética , Humanos , Lactente , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Shigella flexneri/genética , Shigella flexneri/isolamento & purificação , Shigella sonnei/genética , Shigella sonnei/isolamento & purificaçãoRESUMO
Shigella spp are Gram-negative, anaerobic facultative, non-motile, and non-sporulated bacilli of the Enterobacteriaceae family responsible for "Shigellosis" or bacillary dysentery, an important cause of worldwide morbidity and mortality. However, despite this, there are very few epidemiological studies about this bacterium in Brazil. We studied the antibiotic resistance profiles and the clonal structure of 60 Shigella strains (30 S. flexneri and 30 S. sonnei) isolated from shigellosis cases in different cities within the metropolitan area of Campinas, State of São Paulo, Brazil. We used the following well-characterized molecular techniques: enterobacterial repetitive intergenic consensus, repetitive extragenic palindromic, and double-repetitive element-polymerase chain reaction to characterize the bacteria. Also, the antibiotic resistance of the strains was determined by the diffusion disk method. Many strains of S. flexneri and S. sonnei were found to be multi-resistant. S. flexneri strains were resistant to ampicillin in 83.3 percent of cases, chloramphenicol in 70.0 percent, streptomycin in 86.7 percent, sulfamethoxazole in 80.0 percent, and tetracycline in 80.0 percent, while a smaller number of strains were resistant to cephalothin (3.3 percent) and sulfazotrim (10.0 percent). S. sonnei strains were mainly resistant to sulfamethoxazole (100.0 percent) and tetracycline (96.7 percent) and, to a lesser extent, to ampicillin (6.7 percent) and streptomycin (26.7 percent). Polymerase chain reaction-based typing supported the existence of specific clones responsible for the shigellosis cases in the different cities and there was evidence of transmission between cities. This clonal structure would probably be the result of selection for virulence and resistance phenotypes. These data indicate that the human sanitary conditions of the cities investigated should be improved.