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1.
Chem Rec ; 21(1): 17-28, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33274843

RESUMO

Polysaccharide nanoparticles are promising materials in the wide range of disciplines such as medicine, nutrition, food production, agriculture, material science and others. They excel not only in their non-toxicity and biodegradability but also in their easy preparation. As well as inorganic particles, a protein corona (PC) around polysaccharide nanoparticles is formed in biofluids. Moreover, it has been considered that the overall response of the organism to nanoparticles presence depends on the PC. This review summarises scientific publications about the structural chemistry of polysaccharide nanoparticles and their impact on theranostic applications. Three strategies of implementation of the PC in theranostics have been discussed: I) Utilisation of the PC in therapy; II) How the composition of the PC is analysed for specific disease markers; III) How the formed PC can interact with the immune system and enhances the immunomodulation or immunoelimination. Thus, the findings from this review can contribute to improve the design of drug delivery systems. However, it is still necessary to elucidate the mechanisms of nano-bio interactions and discover new connections in nanoscale research.


Assuntos
Nanopartículas/química , Polissacarídeos/química , Coroa de Proteína , Nanomedicina Teranóstica/métodos , Adjuvantes Imunológicos/uso terapêutico , Aterosclerose/diagnóstico por imagem , Biomarcadores/análise , Humanos , Imunidade Humoral/efeitos dos fármacos , Nanopartículas/uso terapêutico , Neoplasias/diagnóstico por imagem , Polissacarídeos/uso terapêutico , Coroa de Proteína/imunologia
2.
Pharmaceutics ; 12(9)2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32872234

RESUMO

Silver nanoparticles (AgNPs) have recently become very attractive for the scientific community due to their broad spectrum of applications in the biomedical field. The main advantages of AgNPs include a simple method of synthesis, a simple way to change their morphology and high surface area to volume ratio. Much research has been carried out over the years to evaluate their possible effectivity against microbial organisms. The most important factors which influence the effectivity of AgNPs against microorganisms are the method of their preparation and the type of application. When incorporated into fabric wound dressings and other textiles, AgNPs have shown significant antibacterial activity against both Gram-positive and Gram-negative bacteria and inhibited biofilm formation. In this review, the different routes of synthesizing AgNPs with controlled size and geometry including chemical, green, irradiation and thermal synthesis, as well as the different types of application of AgNPs for wound dressings such as membrane immobilization, topical application, preparation of nanofibers and hydrogels, and the mechanism behind their antimicrobial activity, have been discussed elaborately.

3.
Nanomaterials (Basel) ; 10(5)2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32365860

RESUMO

The irradiance of ultraviolet (UV) radiation is a physical parameter that significantly influences biological molecules by affecting their molecular structure. The influence of UV radiation on nanoparticles has not been investigated much. In this work, the ability of cadmium telluride quantum dots (CdTe QDs) to respond to natural UV radiation was examined. The average size of the yellow QDs was 4 nm, and the sizes of green, red and orange QDs were 2 nm. Quantum yield of green CdTe QDs-MSA (mercaptosuccinic acid)-A, yellow CdTe QDs-MSA-B, orange CdTe QDs-MSA-C and red CdTe QDs-MSA-D were 23.0%, 16.0%, 18.0% and 7.0%, respectively. Green, yellow, orange and red CdTe QDs were replaced every day and exposed to daily UV radiation for 12 h for seven consecutive days in summer with UV index signal integration ranging from 1894 to 2970. The rising dose of UV radiation led to the release of cadmium ions and the change in the size of individual QDs. The shifts were evident in absorption signals (shifts of the absorbance maxima of individual CdTe QDs-MSA were in the range of 6-79 nm), sulfhydryl (SH)-group signals (after UV exposure, the largest changes in the differential signal of the SH groups were observed in the orange, green, and yellow QDs, while in red QDs, there were almost no changes), fluorescence, and electrochemical signals. Yellow, orange and green QDs showed a stronger response to UV radiation than red ones.

4.
Nanomaterials (Basel) ; 9(11)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683686

RESUMO

AgNPs have attracted considerable attention in many applications including industrial use, and their antibacterial properties have been widely investigated. Due to the green synthesis process employed, the nanoparticle surface can be coated with molecules with biologically important characteristics. It has been reported that increased use of nanoparticles elevates the risk of their release into the environment. However, little is known about the behaviour of AgNPs in the eco-environment. In this study, the effect of green synthesized AgNPs on germinated plants of maize was examined. The effects on germination, basic growth and physiological parameters of the plants were monitored. Moreover, the effect of AgNPs was compared with that of Ag(I) ions in the form of AgNO3 solution. It was found that the growth inhibition of the above-ground parts of plants was about 40%, and AgNPs exhibited a significant effect on photosynthetic pigments. Significant differences in the following parameters were observed: weights of the caryopses and fresh weight (FW) of primary roots after 96 h of exposure to Ag(I) ions and AgNPs compared to the control and between Ag compounds. In addition, the coefficient of velocity of germination (CVG) between the control and the AgNPs varied and that between the Ag(I) ions and AgNPs was also different. Phytotoxicity was proved in the following sequence: control < AgNPs < Ag(I) ions.

5.
Chem Rec ; 19(2-3): 502-522, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30156367

RESUMO

Cancer represents one of the main causes of human death in developed countries. Most current therapies, unfortunately, carry a number of side effects, such as toxicity and damage to healthy cells, as well as the risk of resistance and recurrence. Therefore, cancer research is trying to develop therapeutic procedures with minimal negative consequences. The use of nanomaterial-based systems appears to be one of them. In recent years, great progress has been made in the field using nanomaterials with high potential in biomedical applications. Carbon nanomaterials, thanks to their unique physicochemical properties, are gaining more and more popularity in cancer therapy. They are valued especially for their ability to deliver drugs or small therapeutic molecules to these cells. Through surface functionalization, they can specifically target tumor tissues, increasing the therapeutic potential and significantly reducing the adverse effects of therapy. Their potential future use could, therefore, be as vehicles for drug delivery. This review presents the latest findings of research studies using carbon nanomaterials in the treatment of various types of cancer. To carry out this study, different databases such as Web of Science, PubMed, MEDLINE and Google Scholar were employed. The findings of research studies chosen from more than 2000 viewed scientific publications from the last 15 years were compared.


Assuntos
Antineoplásicos/uso terapêutico , Carbono/química , Portadores de Fármacos/química , Neoplasias/tratamento farmacológico , Neoplasias/terapia , Pontos Quânticos/química , Animais , Humanos
6.
J Nanosci Nanotechnol ; 19(5): 2483-2488, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30501743

RESUMO

Modern anticancer therapy aims to increase the effectiveness of tumor treatment. The aim of this work was to propose a new nanotransporter for targeted delivery of anthracycline antibiotics, which is characterized by its bioavailability, increased uptake of the drug from the bloodstream at the site of the tumor tissue as well as low toxicity to non-target tissue. Chitosan nanoparticles have attracted great attention in the field of drug delivery due to their stability, low toxicity and easy preparation. Deacetylated chitosan skeleton is composed of glucosamine units and has a high density of charged amino groups which allow strong electrostatic interactions with biomolecules, transition metals (Zn, Se) and peptides. We obtained an effective level of chitosan encapsulation, 20%. Electrochemical detection of the bounded Zn2+ ions into the chitosan structure showed a potential shift from -0.99 to -0.93 V. This result proved the formation of a chitosan-zinc complex. The ability of metallothione to quench the 2,2-diphenyl-1-picrylhydrazyl radical in the presence of 50 µM doxorubicin was confirmed by the change of relative absorbance over the range from 50 to 60%.


Assuntos
Antineoplásicos , Quitosana , Nanopartículas , Preparações Farmacêuticas , Antibióticos Antineoplásicos , Doxorrubicina/farmacologia , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Zinco
7.
J Nanosci Nanotechnol ; 19(5): 2762-2769, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30501777

RESUMO

Silver nanoparticles are the most important nanoparticles in connection with the antimicrobial effect. Nowadays, the green synthesis of various types of nanoparticles is rapid, effective and produce less toxic nanoparticles often with specific properties. In our experiment we have developed and described in details various types of silver nanoparticles synthesized chemically or by the green synthesis. Nine different silver nanoparticles were synthesized, three by citrate method at different pHs (8; 9; 10), four using gallic acid at alkaline pHs (10; 11), and two by green synthesis using green tea and coffee extracts, both at pH 9. Characterisation of silver nanoparticles was performed using dynamic light scattering, scanning electron microscopy, and ultraviolet-visible absorption spectroscopy. Silver nanoparticles prepared by green synthesis showed the highest antioxidant activity and also ability for quenching of free radicals. Antibacterial activity of silver nanoparticles was determined on bacterial cultures such as Staphylococcus aureus and Escherichia coli. Silver nanoparticles synthesized using green tea and coffee extracts showed the highest antibacterial activity for both bacterial strains. Minimal inhibition concentration for both strains was found to be 65 µM at each silver nanoparticle synthesized using green synthesis.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Química Verde , Testes de Sensibilidade Microbiana , Extratos Vegetais , Prata/farmacologia
8.
Int J Mol Sci ; 19(12)2018 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-30467297

RESUMO

BACKGROUND: Sarcosine is an amino acid that is formed by methylation of glycine and is present in trace amounts in the body. Increased sarcosine concentrations in blood plasma and urine are manifested in sarcosinemia and in some other diseases such as prostate cancer. For this purpose, sarcosine detection using the nanomedicine approach was proposed. In this study, we have prepared superparamagnetic iron oxide nanoparticles (SPIONs) with different modified surface area. Nanoparticles (NPs) were modified by chitosan (CS), and sarcosine oxidase (SOX). SPIONs without any modification were taken as controls. Methods and Results: The obtained NPs were characterized by physicochemical methods. The size of the NPs determined by the dynamic light scattering method was as follows: SPIONs/Au/NPs (100⁻300 nm), SPIONs/Au/CS/NPs (300⁻700 nm), and SPIONs/Au/CS/SOX/NPs (600⁻1500 nm). The amount of CS deposited on the NP surface was found to be 48 mg/mL for SPIONs/Au/CS/NPs and 39 mg/mL for SPIONs/Au/CS/SOX/NPs, and repeatability varied around 10%. Pseudo-peroxidase activity of NPs was verified using sarcosine, horseradish peroxidase (HRP) and 3,3',5,5'-tetramethylbenzidine (TMB) as a substrate. For TMB, all NPs tested evinced substantial pseudo-peroxidase activity at 650 nm. The concentration of SPIONs/Au/CS/SOX/NPs in the reaction mixture was optimized to 0⁻40 mg/mL. Trinder reaction for sarcosine detection was set up at 510 nm at an optimal reaction temperature of 37 °C and pH 8.0. The course of the reaction was linear for 150 min. The smallest amount of NPs that was able to detect sarcosine was 0.2 mg/well (200 µL of total volume) with the linear dependence y = 0.0011x - 0.0001 and the correlation coefficient r = 0.9992, relative standard deviation (RSD) 6.35%, limit of detection (LOD) 5 µM. The suggested method was further validated for artificial urine analysis (r = 0.99, RSD 21.35%, LOD 18 µM). The calculation between the detected and applied concentrations showed a high correlation coefficient (r = 0.99). NPs were tested for toxicity and no significant growth inhibition was observed in any model system (S. cerevisiae, S. aureus, E. coli). The hemolytic activity of the prepared NPs was similar to that of the phosphate buffered saline (PBS) control. The reaction system was further tested on real urine specimens. Conclusion: The proposed detection system allows the analysis of sarcosine at micromolar concentrations and to monitor changes in its levels as a potential prostate cancer marker. The whole system is suitable for low-cost miniaturization and point-of-care testing technology and diagnostic systems. This system is simple, inexpensive, and convenient for screening tests and telemedicine applications.


Assuntos
Biomarcadores Tumorais/urina , Quitosana/química , Nanopartículas de Magnetita/química , Neoplasias da Próstata/diagnóstico , Sarcosina Oxidase/química , Sarcosina/urina , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Compostos Férricos/química , Ouro/química , Hemólise/efeitos dos fármacos , Peroxidase do Rábano Silvestre/química , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Nanopartículas de Magnetita/ultraestrutura , Masculino , Oxirredução , Tamanho da Partícula , Medicina de Precisão , Neoplasias da Próstata/urina , Reprodutibilidade dos Testes , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
9.
Int J Nanomedicine ; 13: 2107-2128, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29692609

RESUMO

Traditional supplements of selenium generally have a low degree of absorption and increased toxicity. Therefore, it is imperative to develop innovative systems as transporters of selenium compounds, which would raise the bioavailability of this element and allow its controlled release in the organism. Nanoscale selenium has attracted a great interest as a food additive especially in individuals with selenium deficiency, but also as a therapeutic agent without significant side effects in medicine. This review is focused on the incorporation of nanotechnological applications, in particular exploring the possibilities of a more effective way of administration, especially in selenium-deficient organisms. In addition, this review summarizes the survey of knowledge on selenium nanoparticles, their biological effects in the organism, advantages, absorption mechanisms, and nanotechnological applications for peroral administration.


Assuntos
Aditivos Alimentares/química , Nanopartículas/administração & dosagem , Selênio/administração & dosagem , Selênio/farmacocinética , Administração Oral , Sistemas de Liberação de Medicamentos/métodos , Aditivos Alimentares/administração & dosagem , Humanos , Mucosa Intestinal/efeitos dos fármacos , Nanomedicina/métodos , Nanopartículas/química , Nanotecnologia
10.
Int J Mol Sci ; 18(10)2017 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-29065468

RESUMO

Selenium is an essential trace element important for many physiological processes, especially for the functions of immune and reproductive systems, metabolism of thyroid hormones, as well as antioxidant defense. Selenium deficiency is usually manifested by an increased incidence of retention of placenta, metritis, mastitis, aborts, lowering fertility and increased susceptibility to infections. In calves, lambs and kids, the selenium deficiency demonstrates by WMD (white muscle disease), in foals and donkey foals, it is associated with incidence of WMD and yellow fat disease, and in pigs it causes VESD (vitamin E/selenium deficiency) syndrome. The prevention of these health disorders can be achieved by an adequate selenium supplementation to the diet. The review summarizes the survey of knowledge on selenium, its biological significance in the organism, the impact of its deficiency in mammalian livestock (comparison of ruminants vs. non-ruminants, herbivore vs. omnivore) and possibilities of its peroral administration. The databases employed were as follows: Web of Science, PubMed, MEDLINE and Google Scholar.


Assuntos
Mamíferos/metabolismo , Selênio/metabolismo , Animais , Suplementos Nutricionais , Feminino , Humanos , Masculino , Selênio/deficiência , Selênio/fisiologia
11.
PLoS One ; 12(7): e0180798, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28704436

RESUMO

Sparsely tested group of platinum nanoparticles (PtNPs) may have a comparable effect as complex platinum compounds. The aim of this study was to observe the effect of PtNPs in in vitro amplification of DNA fragment of phage λ, on the bacterial cultures (Staphylococcus aureus), human foreskin fibroblasts and erythrocytes. In vitro synthesized PtNPs were characterized by dynamic light scattering (PtNPs size range 4.8-11.7 nm), zeta potential measurements (-15 mV at pH 7.4), X-ray fluorescence, UV/vis spectrophotometry and atomic absorption spectrometry. The PtNPs inhibited the DNA replication and affected the secondary structure of DNA at higher concentrations, which was confirmed by polymerase chain reaction, DNA sequencing and DNA denaturation experiments. Further, cisplatin (CisPt), as traditional chemotherapy agent, was used in all parallel experiments. Moreover, the encapsulation of PtNPs in liposomes (LipoPtNPs) caused an approximately 2.4x higher of DNA damage in comparison with CisPt, LipoCisPt and PtNPs. The encapsulation of PtNPs in liposomes also increased their antibacterial, cytostatic and cytotoxic effect, which was determined by the method of growth curves on S. aureus and HFF cells. In addition, both the bare and encapsulated PtNPs caused lower oxidative stress (determined by GSH/GSSG ratio) in the human erythrocytes compared to the bare and encapsulated CisPt. CisPt was used in all parallel experiments as traditional chemotherapy agent.


Assuntos
Dano ao DNA , Replicação do DNA , Nanopartículas Metálicas/efeitos adversos , Linhagem Celular , Células Cultivadas , Eritrócitos/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Humanos , Nanopartículas Metálicas/química , Estresse Oxidativo , Platina/efeitos adversos , Platina/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética
12.
J Nanobiotechnology ; 15(1): 33, 2017 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-28446250

RESUMO

Nanomaterials in agriculture are becoming popular due to the impressive advantages of these particles. However, their bioavailability and toxicity are key features for their massive employment. Herein, we comprehensively summarize the latest findings on the phytotoxicity of nanomaterial products based on essential metals used in plant protection. The metal nanoparticles (NPs) synthesized from essential metals belong to the most commonly manufactured types of nanomaterials since they have unique physical and chemical properties and are used in agricultural and biotechnological applications, which are discussed. The paper discusses the interactions of nanomaterials and vascular plants, which are the subject of intensive research because plants closely interact with soil, water, and atmosphere; they are also part of the food chain. Regarding the accumulation of NPs in the plant body, their quantification and localization is still very unclear and further research in this area is necessary.


Assuntos
Agricultura , Nanopartículas Metálicas/toxicidade , Metais/toxicidade , Nanotecnologia , Fenômenos Fisiológicos Vegetais/efeitos dos fármacos , Plantas/efeitos dos fármacos , Agricultura/métodos , Nanopartículas Metálicas/química , Metais/química , Metais/metabolismo , Nanotecnologia/métodos , Plantas/metabolismo , Testes de Toxicidade/métodos
13.
J Biochem Mol Toxicol ; 31(6)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28059470

RESUMO

Hyperglycemia, a major metabolic disturbance present in diabetes, promotes oxidative stress. Activation of antioxidant defense is an important mechanism to prevent cell damage. Levels of heavy metals and their binding proteins can contribute to oxidative stress. Antiradical capacity and levels of metallothionein (MT), metals (zinc and copper), and selected antioxidants (bilirubin, cysteine, and glutathione) were determined in 70 type 2 diabetes mellitus (T2DM) subjects and 80 healthy subjects of Caucasian origin. Single nucleotide polymorphism (rs28366003) in MT gene was detected. Antiradical capacity, conjugated bilirubin, and copper were significantly increased in diabetics, whereas MT and glutathione were decreased. Genotype AA of rs28366003 was associated with higher zinc levels in the diabetic group. The studied parameters were not influenced by renal function. This is the first study comprehensively investigating differences in MT and metals relevant to oxidative stress in T2DM. Ascertained differences indicate increased oxidative stress in T2DM accompanied by abnormalities in non-enzymatic antioxidant defense systems.


Assuntos
Cobre/sangue , Diabetes Mellitus Tipo 2/complicações , Nefropatias Diabéticas/sangue , Metalotioneína/genética , Estresse Oxidativo , Insuficiência Renal Crônica/sangue , Zinco/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Estudos de Casos e Controles , República Tcheca , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/fisiopatologia , Feminino , Estudos de Associação Genética , Humanos , Rim/fisiopatologia , Masculino , Metalotioneína/sangue , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/fisiopatologia , Índice de Gravidade de Doença
14.
Nanomaterials (Basel) ; 7(12)2017 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-29292780

RESUMO

This work investigated the preparation of chitosan nanoparticles used as carriers for doxorubicin for targeted cancer delivery. Prepared nanocarriers were stabilized and functionalized via zinc ions incorporated into the chitosan nanoparticle backbone. We took the advantage of high expression of sarcosine in the prostate cancer cells. The prostate cancer targeting was mediated by the AntiSar antibodies decorated surface of the nanocage. Formation of the chitosan nanoparticles was determined using a ninhydrin assay and differential pulse voltammetry. Obtained results showed the strong effect of tripolyphosphine on the nanoparticle formation. The zinc ions affected strong chitosan backbone coiling both in inner and outer chitosan nanoparticle structure. Zinc electrochemical signal depended on the level of the complex formation and the potential shift from -960 to -950 mV. Formed complex is suitable for doxorubicin delivery. It was observed the 20% entrapment efficiency of doxorubicin and strong dependence of drug release after 120 min in the blood environment. The functionality of the designed nanotransporter was proven. The purposed determination showed linear dependence in the concentration range of Anti-sarcosine IgG labeled gold nanoparticles from 0 to 1000 µg/mL and the regression equation was found to be y = 3.8x - 66.7 and R² = 0.99. Performed ELISA confirmed the ability of Anti-sarcosine IgG labeled chitosan nanoparticles with loaded doxorubicin to bind to the sarcosine molecule. Observed hemolytic activity of the nanotransporter was 40%. Inhibition activity of our proposed nanotransporter was evaluated to be 0% on the experimental model of S. cerevisiae. Anti-sarcosine IgG labeled chitosan nanoparticles, with loaded doxorubicin stabilized by Zn ions, are a perspective type of nanocarrier for targeted drug therapy managed by specific interaction with sarcosine and metallothionein for prostate cancer.

15.
Int J Mol Sci ; 17(5)2016 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-27164078

RESUMO

The majority of carcinomas that were developed due to the infection with human papillomavirus (HPV) are caused by high-risk HPV types, HPV16 and HPV18. These HPV types contain the E6 and E7 oncogenes, so the fast detection of these oncogenes is an important point to avoid the development of cancer. Many different HPV tests are available to detect the presence of HPV in biological samples. The aim of this study was to design a fast and low cost method for HPV identification employing magnetic isolation, polymerase chain reaction (PCR) and electrochemical detection. These assays were developed to detect the interactions between E6-HPV16 oncogene and magnetizable particles (MPs) using commercial Dynabeads M-280 Streptavidin particles and laboratory-synthesized "homemade" particles called MANs (MAN-37, MAN-127 and MAN-164). The yields of PCR amplification of E6-HPV16 oncogene bound on the particles and after the elution from the particles were compared. A highest yield of E6-HPV16 DNA isolation was obtained with both MPs particles commercial M-280 Streptavidin and MAN-37 due to reducing of the interferents compared with the standard PCR method. A biosensor employing the isolation of E6-HPV16 oncogene with MPs particles followed by its electrochemical detection can be a very effective technique for HPV identification, providing simple, sensitive and cost-effective analysis.


Assuntos
Nanopartículas de Magnetita/química , Técnicas de Diagnóstico Molecular/métodos , Proteínas Oncogênicas Virais/química , Proteínas Repressoras/química , Papillomavirus Humano 16/química , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/isolamento & purificação , Proteínas Oncogênicas Virais/genética , Reação em Cadeia da Polimerase/métodos , Proteínas Repressoras/genética , Estreptavidina/química
16.
Sensors (Basel) ; 16(3): 290, 2016 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-26927112

RESUMO

Liposome-based drug delivery systems hold great potential for cancer therapy. The aim of this study was to design a nanodevice for targeted anchoring of liposomes (with and without cholesterol) with encapsulated anticancer drugs and antisense N-myc gene oligonucleotide attached to its surface. To meet this main aim, liposomes with encapsulated doxorubicin, ellipticine and etoposide were prepared. They were further characterized by measuring their fluorescence intensity, whereas the encapsulation efficiency was estimated to be 16%. The hybridization process of individual oligonucleotides forming the nanoconstruct was investigated spectrophotometrically and electrochemically. The concentrations of ellipticine, doxorubicin and etoposide attached to the nanoconstruct in gold nanoparticle-modified liposomes were found to be 14, 5 and 2 µg·mL(-1), respectively. The study succeeded in demonstrating that liposomes are suitable for the transport of anticancer drugs and the antisense oligonucleotide, which can block the expression of the N-myc gene.


Assuntos
DNA Antissenso/uso terapêutico , Sistemas de Liberação de Medicamentos , Nanopartículas de Magnetita/química , Neoplasias/tratamento farmacológico , DNA Antissenso/química , Doxorrubicina/química , Doxorrubicina/uso terapêutico , Elipticinas/química , Elipticinas/uso terapêutico , Etoposídeo/química , Etoposídeo/uso terapêutico , Fluorescência , Ouro/química , Humanos , Lipossomos/química , Lipossomos/uso terapêutico , Nanopartículas de Magnetita/uso terapêutico , Proteína Proto-Oncogênica N-Myc/antagonistas & inibidores , Proteína Proto-Oncogênica N-Myc/genética
17.
Curr Drug Targets ; 17(12): 1438-51, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26424389

RESUMO

Cardiotoxicity is a serious complication of anticancer therapy by anthracycline antibiotics. Except for intercalation into DNA/RNA structure, inhibition of DNA-topoisomerase and histone eviction from chromatin, the main mechanism of their action is iron-mediated formation of various forms of free radicals, which leads to irreversible damage to cancer cells. The most serious adverse effect of anthracyclines is, thus, cardiomyopathy leading to congestive heart failure, which is caused by the same mechanisms. Here, we briefly summarize the basic types of free radicals formed by anthracyclines and the main processes how to scavenge them. From these, the main attention is paid to metallothioneins. These low-molecular cysteine-rich proteins are introduced and their functions and properties are reviewed. Further, their role in detoxification of metals and drugs is discussed. Based on these beneficial roles, their use as a new therapeutic agent against oxidative stress and for cardioprotection is critically evaluated with respect to their ability to increase chemoresistance against some types of commonly used cytostatics.


Assuntos
Antibióticos Antineoplásicos/efeitos adversos , Cardiomiopatias/etiologia , Metalotioneína/farmacologia , Animais , Antraciclinas/administração & dosagem , Antraciclinas/efeitos adversos , Antibióticos Antineoplásicos/administração & dosagem , Cardiomiopatias/prevenção & controle , Cardiotônicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Sequestradores de Radicais Livres/farmacologia , Radicais Livres/metabolismo , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/prevenção & controle , Humanos , Metalotioneína/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Estresse Oxidativo/efeitos dos fármacos
18.
Acta Medica (Hradec Kralove) ; 58(1): 21-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26454803

RESUMO

Melatonin is a hormone with strong antioxidant properties. In this experiment, Freund's complete adjuvant was used as a stressogenic substance given to laboratory outbred mice, whereas melatonin was investigated as a protectant against the stressogenic effect. Levels of low molecular weight antioxidants, thiobarbituric acid reactive substances, and tumor necrosis factor α and activity of glutathione reductase were determined in blood from the animals. Surprisingly, melatonin was not involved in direct regulation of antioxidants, thiobarbituric acid reactive substances and tumor necrosis factor α. On the other hand, melatonin regulated glutathione reductase activity. We can conclude on regulation of metabolism caused by melatonin in the model. The effect was more important than the expected regulation of immunity and basal oxidative homeostasis.


Assuntos
Adjuvantes Imunológicos/farmacologia , Antioxidantes/farmacologia , Antioxidantes/fisiologia , Adjuvante de Freund/farmacologia , Melatonina/farmacologia , Melatonina/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Animais , Relação Dose-Resposta a Droga , Feminino , Camundongos
19.
Electrophoresis ; 36(19): 2367-79, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26046318

RESUMO

Nanofluidics is becoming an extensively developing technique in the field of bioanalytical chemistry. Nanoscale hole embed in an insulating membrane is employed in a vast variety of sensing platforms and applications. Although, biological nanopores have several attractive characteristics, in this paper, we focused on the solid-state nanopores due to their advantages as high stability, possibility of diameter control, and ease of surface functionalizing. A detection method, based on the translocation of analyzed molecules through nanochannels under applied voltage bias and resistive pulse sensing, is well established. Nevertheless, it seems that the new detection methods like measuring of transverse electron tunneling using nanogap electrodes or optical detection can offer significant additional advantages. The aim of this review is not to cite all related articles, but highlight the steps, which in our opinion, meant important progresses in solid-state nanopore analysis.


Assuntos
Eletrônica , Nanoporos , Nanotecnologia , Técnicas Analíticas Microfluídicas , Propriedades de Superfície
20.
J Mater Chem B ; 3(10): 2109-2118, 2015 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32262379

RESUMO

The aim of this study was to synthesize cadmium telluride nanoparticles (CdTe NPs) modified apoferritin, and examine if apoferritin is able to accommodate CdTe NPs. Primarily, the thermostability of horse spleen apoferritin was tested and it's unfolding at 70 °C was observed. Cadmium telluride nanoparticles (CdTe NPs) were synthesized both within apoferritin protein cage and on its surface. The thermal treatment of apoferritin with CdTe NPs resulted in the aggregation of cores, which was indicated by changes in the absorption spectra and the shape of apoferritin tryptophan fluorescence. The apoferritin modified with CdTe NPs was additionally modified with gold nanoparticles and attached to magnetic particles via oligonucleotide using gold affinity to thiol group. This anchor system was used to separate the construct using external magnetic field and to analyse the molecules attached to apoferritin.

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