Článek si všímá posledních prezentovaných prací s problematikou elektrochemické detekce insulinu a předkládá kritický pohled na výzkum a vývoj jeho elektrochemických neenzymových senzorů. Monitoruje vliv experimentálních podmínek na insulinový oxidační signál a zamýšlí se nad katalytickými efekty nanočástic či nanokompozitů deponovaných na površích elektrochemického snímače.
The article notes the latest presented work on the electrochemical detection of insulin and presents a critical view of the research and development of its electrochemical non-enzymatic sensors. It monitors the effect of experimental conditions on the insulin oxidation signal and considers the catalytic effects of nanoparticles or nanocomposites deposited on the surfaces of the electrochemical sensor.
The DNA fragment d(GCGAAGC), occurring in the initial replication stage of the phage ?X174, in herpes simplex virus, in the promoter region of the heat-shock gene of E. coli and in rRNA genes is still in the focus of biological and biochemical research. This shortest hairpin guided us to study the relationship between the structure and function of other heptamers with changing triplet sequence in the center of the ODN molecule (AAA, GGG, CCC). Replacement of the central part of ODN was chosen because it was initially expected that the double peak of the G oxidation signal is due to the difference in the positions of G in the stem and a loop of the initially investigated d (GCGAAGC) fragment. The experiments, however, did not confirm this assumption. In this work, we have focused on the study of the interaction of selected heptamers with the surface of the mercury in order to answer the question to what extent the A + C reduction peaks and double-peak G oxidation signals are able to reflect the structures of heptamers affected by different central tri¬nucleotide sequences. Guanine residues d(GCGGGGC) in the structure of the quadruplex are resistant to structural changes and the voltammetric responses are therefore mini¬mized. The interactions of quadruplexes with the surface of the electrode are also weaker than interactions of hairpin structures d(GCGAAGC), d(GCAAAGC) and the duplex structure d(GCCCCGC). The presented research has shown that a small change in the central sequence not only can alter the structure (tetramolecular quadruplex, hairpin, bimolecular duplex) but also influences the electrochemical and adsorption properties of these molecules on the charged interface. Although electrochemistry is able to detect the various structural layout of the studied heptamers, it is desirable to support the electrochemical conclusions with other methods, e.g., UV-VIS absorption spectra reflecting chiroptic properties of ODNs and separation methods, such as gel electrophoresis (PAGE).
In this study we have chosen a new approach and characterized three miRNAs (miR-23a, miR-34a and miR-320a) related to prostate cancer and head and neck cancer by spectral (circular dichroic and UV-absorption spectra) and electrochemical (voltammetry at graphite and mercury electrodes) methods. The spectral and voltammetric results, reflecting different nucleotide sequences of miRNAs, were complemented by the results of DNAs(U) having the same oligonucleotide sequences as miRNAs. The effect of the substitution of ribose for deoxyribose was shown and structural diversity was confirmed. The stability of RNA and DNA(U) was studied using CD and UV-absorption spectroscopy and melting points were calculated. MiRNA-320a with the highest content of guanine provided the highest melting point. With respect to the rapid progress of miRNA electrochemical sensors, our results will be useful for the research and development of sensitive, portable and time-efficient miRNA sensors, which will be able to diagnose cancer and other diseases.
- MeSH
- cirkulární dichroismus metody MeSH
- elektrochemie metody MeSH
- fotoelektronová spektroskopie metody MeSH
- lidé MeSH
- mikro RNA krev MeSH
- nádorové biomarkery krev MeSH
- nádory hlavy a krku krev MeSH
- nádory prostaty krev MeSH
- studie případů a kontrol MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Previously, it has been proved that resveratrol exhibits beneficial effect towards human health, maily due to its antioxidant attributes. Naturally, resveratrol occurs in its trans- form and is contained in plenty of plants, but the highest levels were determined in grapevine (Vitis vinifera L.). Thus, a wine contains negligible amounts of this attractive substance and consumption of a wine in appropriate quantity provides advantageous effects on the human body.
Many studies have already proven the positive effects of flavonoids on organisms. There are many plants which content important amounts of these secondary metabolites in their bodies, one of those being certainly vine (Vitis vinifera). The consumption of wine products is very popular all over the world and it is also connected with the health beneficial effects that it provides. Red wines content more flavonoids then other white or rosé varieties. It is mainly the consequence of the winemaking process during which the grape skin is either removed of left to release its secondary metabolite content, in case of the red and partially the rosé varieties
- MeSH
- antioxidancia MeSH
- flavonoidy * metabolismus terapeutické užití MeSH
- lidé MeSH
- víno * MeSH
- Vitis MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
Multiplex PCR is one of the many variants routinely performed by polymerase chain reaction (PCR). Its advantage is especially rapid detection of a large number of products in one reaction using multiple primer sets. Optimization of the multiplex PCR protocol is important also for genes of metallothionein isoforms, so that we can carry out the amplification of more than one DNA sequence. Necessary part of this proces is the adjustments in temperature during the reaction steps and also intervention with the changes in the concentration of individual reagents and different combinations or the amount of each primer.
One of the possible usages of MALDI–TOF MS is identification of microorganisms. It is highly accurate and faster than other methods and suitable for a large area of microorganisms. But unfortunately cannot reliably differentiate some closely related species. Often, it is possible to detect pathogenic organisms and use their accurate determination for monitoring environment, food processing or clinical diagnostics. Data obtained from mass spectra are compared with library of microorganisms and result of this was agreement or disagreement of microorganisms with specific spectrum.
- Klíčová slova
- identifikace bakterií,
- MeSH
- Bacteria * izolace a purifikace MeSH
- spektrometrie hmotnostní - ionizace laserem za účasti matrice metody MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
The tumor is a cellular process, whose essence is the change of the genetic information and regulatory processes in the cell. Consequently, occurs to the uncontrolled multiplication of cells. Cytostatics, especially anthracycline antibiotics are currently widely used for example in the treatment of breast cancer or prostate cancer, which are nowadays the most frequent cancers. The influence of non-platinum cytotoxic drug doxorubicin on polymerase chain reaction can be studied using fluorescent labelling of amplicons. Due to numerous side-effects of doxorubicin, it is important to know its mechanism of influence on living cells. Polymerase chain reaction can serve as a suitable model of replication in living cells.
- Publikační typ
- abstrakt z konference MeSH
- Klíčová slova
- ssDNA, square-ware voltametrie,
- MeSH
- antracykliny * aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- cytostatické látky terapeutické užití MeSH
- doxorubicin MeSH
- elektrochemické techniky metody využití MeSH
- hodnotící studie jako téma MeSH
- lékové interakce * MeSH
- lidé MeSH
- oligonukleotidy biosyntéza MeSH
- Check Tag
- lidé MeSH
