Study of the Ion Radiation Influence on the Parameters of Unijunction Transistors

The object of this report is study the influence of gamma quanta on some parameters of the unijunction transistors to synthesize radioisotope equipment

Instalation For Induction Heating For Testing Thermo Sensors

With constant development and improvement of management systems in modern technological processes, in cars, in production lines and machinery and other fields are increasingly entering the use of different sensors. These sensors are tested on special test simulators, simulating the conditions for a long time close to their work. Often the temperature is in the range of 700-900°C. To achieve these temperatures, most environmentally safe and effective heating of the sensors can be achieved by induction heating of housing them. The object of this report is installation for induction heating system as part of the simulator to test the vibration and temperature thermal sensors

Birth Size of Neonates and Its Association with Seasonality

The aim of the study is to evaluate the relationship between the season of birth and the birth weight and length of Bulgarian newborns.The weight and length data of 6517 (6098 full-term and 419 preterm) live births in 2000–2001 were collected from the birth registry of II Hospital of Obstetrics and Gynaecology “Sheynovo”, Sofia, Bulgaria. Statistical analyses were done using the SPSS 16 software for Windows: descriptive statistics; the t-test (p<0.05); One-Way ANOVA, (Tukey, HSD-test, p<0.05) and the Pearson’s correlation. The sunshine dura-tion data for 2000 and 2001 were collected at the Sofia Meteorological Station.The mean weight of Bulgarian neonates born in 2000-2001 was 3389.8 g in boys and 3261.8 g in girls. The average newborn’s length was 51.0 cm and 50.3 cm in boys and girls, respectively. In all seasons, significant gender differences were observed with a priority for boys (p≤0.001). The winter period was identified with a peak in birth length for both sexes, and spring and summer were the seasons with the lowest values for boys and girls, respectively. A significant positive correlation between birth length and the daily amount of sunshine during the prenatal period was found (p<0.001).Seasonal fluctuations influenced weight and length in Bulgarian neonates. The results obtained in this study can be useful in prenatal diagnostics, neonatal care, and health prevention of pregnant women and neonates

Stability of mRNA/DNA and DNA/DNA Duplexes Affects mRNA Transcription

Nucleic acids, due to their structural and chemical properties, can form double-stranded secondary structures that assist the transfer of genetic information and can modulate gene expression. However, the nucleotide sequence alone is insufficient in explaining phenomena like intron-exon recognition during RNA processing. This raises the question whether nucleic acids are endowed with other attributes that can contribute to their biological functions. In this work, we present a calculation of thermodynamic stability of DNA/DNA and mRNA/DNA duplexes across the genomes of four species in the genus Saccharomyces by nearest-neighbor method. The results show that coding regions are more thermodynamically stable than introns, 3′-untranslated regions and intergenic sequences. Furthermore, open reading frames have more stable sense mRNA/DNA duplexes than the potential antisense duplexes, a property that can aid gene discovery. The lower stability of the DNA/DNA and mRNA/DNA duplexes of 3′-untranslated regions and the higher stability of genes correlates with increased mRNA level. These results suggest that the thermodynamic stability of DNA/DNA and mRNA/DNA duplexes affects mRNA transcription

Nephrotic syndrome after treatment with D-penicillamine in a patient with Wilson’s disease

Wilson’s disease is an inherited autosomal recessive disorder of copper balance leading to accumulation of copper mainly in liver and brain result from absent or reduced function of copper-transporting P-type ATPase. Copper is an essential trace element but in Wilson’s disease it accumulate to the point of toxicity. D-penicillamine is a classic drug for treatment of Wilson’s disease. Its major effect is to promote the urinary copper excretion. The use of D-penicillamine in the therapy of Wilson’s disease is known to be complicated by the development of various glomerular diseases. In this report we describe the development of nephrotic syndrome after 2 years treatment with D-penicillamine in a 31-year-old male undergoing treatment for Wilson’s disease, with a prompt regression at the discontinuation of the drug. We present this case to draw attention to the rare complication as nephrotic syndrome in patients with Wilson’s disease under D-penicillamine treatment and possible underlying causes. It is strongly necessary the therapy and clinical condition of patients with Wilson’s disease to be monitoring regularly - we recommended monthly

Conformational transitions of proteins engaged in dna double-strand break repair, analysed by tryptophan fluorescence emission and fret

We analysed protein-DNA and protein-protein interactions relevant to the repair of DNA DSBs (double-strand breaks) by NHEJ (non-homologous end-joining). Conformational transitions in mammalian DNA ligases III (LigIII) and IV (LigIV), as well as in PARP-1 [poly(ADP-ribose) polymerase-1], were analysed upon binding to double-stranded DNA by changes in tryptophan emission and FRET (Förster resonance energy transfer) from tryptophan to DNA-conjugated Alexa Fluor® 532. For LigIII, two non-equivalent high- and low-affinity DNA-binding sites are detected interacting sequentially with DNA. PARP-1 displays a single high-affinity DNA-binding site and can displace bound DNA fragments from the low-affinity site of LigIII, consistent with its mediator role in LigIII-DNA interactions. For the LX [LigIV-XRCC4 (X-ray cross-complementation group 4)] complex, a single DNA-binding site is detected. Binding of Ku to DNA was accompanied by conformational changes in the protein and intermolecular FRET from dansyl chromophores of the labelled Ku to the Alexa Fluor® chromophores of Alexa Fluor® 532-conjugated DNA. The average distance of 5.7 nm calculated from FRET data is consistent with a location of Ku at the very end of the DNA molecule. Binding of LX to Ku-DNA complexes is associated with conformational changes in Ku, translocating the protein further towards the DNA ends. The protein-protein and protein-DNA interactions detected and analysed generate a framework for the characterization of molecular interactions fundamental to the function of NHEJ pathways in higher eukaryotes

<i>Crithmum maritimum</i> L.—Study on the Histochemical Localization of Essential Oil

Crithmum maritimum L. is a perennial halophyte plant that is a medicinal herb known by people from different cultures since ancient times. However, the therapeutic potential of this halophyte has not been completely investigated, and the scientific data on it are limited. The purpose of the present study was to estimate the chemical composition of the essential oil (EO) obtained from the aerial parts of Crithmum maritimum L. growing wild in Bulgaria, as well as the histolocalization of secretory structures for the synthesis and accumulation of volatile oils. The results obtained on the EO composition of Bulgarian Crithmum maritimum L. provide an opportunity to reveal potential future applications in various fields, such as medicine, pharmacy, agriculture, food, and the cosmetic industry. Gas chromatography with mass spectrometry was performed to assess the chemical profile of the isolated EO. The phenylpropanoid dillapiole was identified as the major compound in the EO, accounting for 34.09% of the total EO. Monoterpene hydrocarbons represented 62.07% of the total oil composition. γ-Terpinene, D-limonene, and β-pinene were the most abundant monoterpene hydrocarbons in the composition of the EO. In addition, histochemical localization of EO in the stem and leaves of Crithmum maritimum L. was carried out. The secretory structures were located in the cortical region of the stem and in the mesophyll tissues of the leaves in the form of secretory ducts. The performed histochemical analysis confirmed the lipophilic nature of the secretion from the duct cells. This is the first report related to the histolocalization and chemical composition of the EO from Bulgarian Crithmum maritimum L. Furthermore, our data indicate some potential possibilities for the evaluation of the therapeutic activity of the EO obtained from this plant species and outline its future applications as a therapeutic agent. Also, the EO from the studied halophyte plant has prominent potential to be used as a biopesticide, which is an environmentally friendly option compared to standard pesticides

Phospholipase A₂‑Induced Remodeling Processes on Liquid-Ordered/Liquid-Disordered Membranes Containing Docosahexaenoic or Oleic Acid: A Comparison Study

Vesicle cycling, which is an important biological event, involves the interplay between membrane lipids and proteins, among which the enzyme phospholipase A₂ (PLA₂) plays a critical role. The capacity of PLA₂ to trigger the budding and fission of liquid-ordered (L_o) domains has been examined in palmitoyl-docosahexaenoylphosphatidylcholine (PDPC) and palmitoyl-oleoylphosphatidylcholine (POPC)/sphingomyelin/cholesterol membranes. They both exhibited a L_o/liquid-disordered (L_d) phase separation. We demonstrated that PLA₂ was able to trigger budding in PDPC-containing vesicles but not POPC ones. The enzymatic activity, line tension, and elasticity of the membrane surrounding the L_o domains are critical for budding. The higher line tension of L_o domains in PDPC mixtures was assigned to the greater difference in order parameters of the coexisting phases. The higher amount of lysophosphatidylcholine generated by PLA₂ in the PDPC-containing mixtures led to a less-rigid membrane, compared to POPC. The more elastic L_d membranes in PDPC mixtures exert a lower counteracting force against the L_o domain bending

Студентска научна конференция "Здравеопазването-днес и утре", 22 Май 2013, Варна

Варненски медицински форум (Varna Medical Forum) V. 2, Suppl 4 (2013