Search the repository

A+ | A- | | SLO | ENG

Abstract: The aim of the project is to develop a detection system for the toxic algae Alexandrium minutum which can be than used as part of biosensor. First, we will isolate a single-domain antibody from a pre-immune library, then subclone its sequence in different vectors and produce it. Finally, we will design alternative ELISA methods and choose the most suitable to quantify the microalgae in water samples.
Keywords: Alexandrium minutum, mikroalge, biosenzorji ELISA
Published in RUNG: 02.11.2018; Views: 3715; Downloads: 0
This document has many files! More...

Abstract: The major causes of Diabetes Mellitus Type 2 (T2DM) are multi-factorial consequences of complex interactions between environmental, social and genetic factors. We investigated the genetic risk factors in Slovene patients with T2DM on a model of microvascular complication – Diabetic Retinopathy (DR). Retrospective case-control study includes a T2DM Slovene population with clinical risk factors for T2DM and DR. Only some of the candidate genes with selected single nucleotid polymorphisms (SNPs) were included: (EDN1 (rs5370, rs3087459, rs1476046), EDNRA (rs5335, rs1801708), EDNRB (rs10507875, rs4885493), NOS3 (rs869109213). By genotyping with either real-time polymerase chain reaction or standard polymerase chain reaction (PCR) we successfully identified the contribution of variable number of tandem repeats rs869109213 in DR progression (Proliferative Diabetic Retinopathy (PDR)) in Slovene patients with T2DM. The joint effect of individual genotypes of rs10507875 in EDNRB and rs869109213 in NOS3 on DR onset (DR) and DR progression (PDR) was demonstrated as well. The joint effect of the two polymorphisms on DR onset (DR) and DR progression (PDR) was greater than the individual effect of each polymorphism separately in the analyzed genetic models. Despite genetic research contributions in DR, linkage studies, and Genome-wide association studies the identification of susceptible loci through candidate gene approaches still remains in its early stages. The frequent approach with an ultimate focus on SNP associations with phenotype is likely to underestimate the roles of genetics in human diseases by disregarding not only the joint effect of multiple loci but the complex interaction network between them. By identifying polymorphisms in genetic disorders in a more systematic way, we will be able to deepen our understanding of the regulatory mechanisms and disease etiology which should lead to a more effective development of mechanism-based therapies as well.
Keywords: endothelin 1, EDN1, endothelin receptor A, EDNRA, endothelin receptor B, EDNRB, nitric oxide synthase 3, NOS3, diabetic retinopathy, DR, diabetes mellitus type 2, T2DM, polymorphism, SNP, genetic model
Published in RUNG: 07.09.2018; Views: 3609; Downloads: 179
Full text (3,06 MB)

Abstract: Environmental pollution in the 21th century still represents a global problem for human and animal health. Despite general awareness about released substances and their degradation products their fate and possibilities of removal are not well investigated. Even though the chemicals released are dispersed and diluted in water cycles, their poor biodegradability and/or strong accumulation can result in the intoxication of exposed organisms. Similarly, as a part of the environment, food can get contaminated by bioactive substances during different steps of preparation. Not only artificial compounds such as pesticides or pharmaceuticals, but also natural toxins enter the food chain and impact negatively on humans' and animals' health. In addition, the activity of some bacteria can influence the production of amines from amino acids after fermentation, to which the human body responds with several symptoms of intoxication. Several analytical methods for the determination of trace levels of broad range contaminants have been developed. Due to the largely robust, selective and sensitive features of the conventional (rearguard) techniques, they represent the first choice for analysing multiple organic compounds in frequently very complex matrices. However, screening (vanguard) methods are paving the way in the chemical analytics as a solution that provides simplicity and rapid analytical responses with binary (yes/no) answers. They require little or no sample treatment as well as more economically-efficient instrumentation. The combination of vanguard-rearguard analytical strategies hence offers a compromise between classical analytical figures of merit and productivity-related characteristics. In the first part of our research feasibility studies for the application of TLS and/or TLM in novel analytical methods for the determination of lipid-lowering drug atorvastatin and a mycotoxin ochratoxin A . The survey on atorvastatin performed spectrophotometrically has shown a decrease of ATV-sulpho-vanillin product at the wavelength of its maximum absorbance after dilution by organic solvent, which was investigated due to the possible increasing of the method sensitivity. As the predicted LODs that could be obtained by TLM (0.3 mg/L) could not reach the concentration of ATV usually present in the environment (ng/L-g/L) further experiments on this subject were therefore not justified. On the other hand, the ELISA assay for the determination of ochratoxin A was performed. In case of μFIA-TLM, the measurements were influenced by high background signal resulting in high LODs of TLM (470 pg/mL), which is known as a background limited technique. It was estimated that the LODs of standard ELISA assay could not be significantly improved, therefore no further research was conducted in this direction. In the second part of the dissertation, a sensitive rearguard system by coupling HPLC and TLS for the determination of biogenic amines in wine samples was developed. Putrescine, cadaverine, histamine and tyramine were separated and detected on a HPLC-TLS system after derivatization by dabsyl chloride. The method was optimized in terms of chromatographic conditions and in terms of TLS parameters. Also, the sensitivity of the newly developed method was evaluated by comparing the TLS detection with DAD detection in terms of LOD values, where TLS showed 3.6-fold improvement compared to DAD. Afterwards, the standard addition calibration was performed and evaluated for its recoveries (86−117%) in the determination of the four BAs. The applicability of the novel method was tested by the analysis of real white and red wine samples and by comparing the results to the standard HPLC-FL method and concentrations of BAs in wine samples were in good accordance. In addition, the dabsylated BAs showed better stability compared to the OPA derivatives as they have not lost the peak intensity after 17h of storage. In the third part, a vanguard system for detection of the overall biogenic amines concentration was developed by employing μFIA-TLM. Initially, NH4Cl standard solutions were applied in the indophenol reaction for batch mode, off-line μFIA-TLM and in an on-line indophenol formation for μFIA-TLM detection. By adding 50 % of EtOH to indophenol we obtained 9-fold improvement. In addition, indophenol showed good stability under TLM conditions. We optimized the microfluidic and TLM parameters in the off-line and on-line indophenol reaction. The addition of 5% ethanol to the reagent in the on-line reaction resulted in the 3-fold improvement of the signal-to-noise ratio. Further on, the overall reaction, including the enzymatic and the following indophenol reaction, was optimized by choosing the optimal buffer (pH=7, 0.5 M) and alkaline conditions (2M NaOH). The influence of interferences from amino compounds was also evaluated and discussed. The off-line and on-line μFIA-TLM were evaluated by their performance characteristics. The LOD for ammonia detection reached 2.3 μM and the applicability in ammonia detection in water samples was discussed. Similar LOD of 3.2 μM was obtained for the overall concentration of BAs and LOD of 3.8 μM for histamine, which is more than 4-folds lower value as the lowest suggested limits of intake for histamine in wine samples (2 mg/L; 18 μM). Finally, an immobilization procedure on magnetic nanoparticles was developed for the possible implementation of the selected enzyme in a miniaturized biosensor.
Keywords: thermal lens spectrometry, thermal lens microscopy, high performance liquid chromatography, microfluidics, biogenic amines, microbial transglutaminase, indophenol (Berthelot) reaction
Published in RUNG: 04.06.2018; Views: 4923; Downloads: 247
Full text (2,90 MB)
This document has many files! More...

Keywords: mladinska književnost, naravoslovje, humanistika
Published in RUNG: 01.12.2017; Views: 4113; Downloads: 0
This document has many files! More...

Abstract: Starši, vzgojitelji in zdravniki gluhih otrok so si edini: želijo jih pripraviti za samostojno življenje in jih čim bolj vključiti v družbo. Ta želja je plemenita, vendar pa je vključevanje lahko uspešno le, če pri njem upoštevamo zakonitosti jezikovnega razvoja. V tem priročniku boste izvedeli: kaj je jezik in kako se razlikuje od drugih načinov sporazumevanja; kdaj in na kakšen način otrok usvoji jezik; kako pomemben je jezik za otrokov razvoj v najzgodnejšem obdobju; zakaj gluhi otroci pogosto zaostajajo v jezikovnem razvoju in posledično tudi v razvoju nekaterih splošnih miselnih sposobnosti; kako lahko ukrepate, da bo vaš otrok po običajni poti usvojil jezik – in se izognil zaostanku.
Keywords: Usvajanje jezika, gluhota, slovenski znakovni jezik
Published in RUNG: 06.11.2017; Views: 4957; Downloads: 0
This document has many files! More...