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In this work, we carried out a theoretical investigation regarding amphetamine-type stimulants, which can cause central nervous system degeneration, interacting with human DNA. These include amphetamine, methamphetamine, 3,4-Methylenedioxymethamphetamine (also known as ecstasy), as well as their main metabolites. The studies were performed through molecular docking and molecular dynamics simulations, where molecular interactions of the receptor–ligand systems, along with their physical–chemical energies, were reported. Our results show that 3,4-Methylenedioxymethamphetamine and 3,4-Dihydroxymethamphetamine (ecstasy) present considerable reactivity with the receptor (DNA), suggesting that these molecules may cause damage due to human-DNA. These results were indicated by free Gibbs change of bind (ΔGbind) values referring to intermolecular interactions between the drugs and the minor grooves of DNA, which were predominant for all simulations. In addition, it was observed that 3,4-Dihydroxymethamphetamine (ΔGbind = ?13.15 kcal/mol) presented greater spontaneity in establishing interactions with DNA in comparison to 3,4-Methylenedioxymethamphetamine (ΔGbind = ?8.61 kcal/mol). Thus, according with the calculations performed our results suggest that the 3,4-Methylenedioxymethamphetamine and 3,4-Dihydroxymethamphetamine have greater probability to provide damage to human DNA fragments.  相似文献   
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Small algae are the trophic basis in both marine and freshwater ecosystems. The identification of tiny microorganisms and place of their origin is laborious but necessary. This paper consists of a literature review of 17 species of planktonic algae, with a discussion of taxonomic problems. We also clarify whether these 17 species are non-native, invasive or cryptogenic species, with an indication whether they had been recognised as ‘alien’ in Europe. According to our observations, areas colonized by small and alien algal species, were anthropogenically altered. There were: systems with heated waters (‘heated islands’), which imitated tropical conditions; highly eutrophic to hypereutrophic water ecosystems, easily colonized by alien species, fishponds with intense fish cultivation, where alien species of fish are/had been introduced, which carried also other alien organisms; and inland water ecosystems with high salinity or high conductivity e.g. pits inundated by mine waters, imitating sea or brackish conditions acting as hubs of migration of alien species adapted to brackish or saline waters. We have prepared a map showing areas inhabited by alien species, both of documented places and hypothetical ones, where we would expect alien species to occur.  相似文献   
25.
5-Arylcarbamoyl-2-methylisoxazolidin-3-yl-3-phosphonates have been synthesised from N-methyl-C-diethoxyphosphorylnitrone and N-arylacrylamides in good yields. cis- and trans-isoxazolidine phosphonates obtained herein were evaluated for activity against a broad range of DNA and RNA viruses. None of the compounds were endowed with antiviral activity at subtoxic concentrations. Isoxazolidines having phenyl substituted with halogen (Ar = 2-F-C6H4; 3-Br-C6H4; and 4-Br-C6H4) have been found to inhibit proliferation of L1210, CEM as well as HeLa cells with IC50 in the 100–170 μM range.  相似文献   
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In the present work, we optimised and evaluated a qPCR system integrating 6-FAM (6-carboxyfluorescein)-labelled TaqMan probes and melting analysis using the SYTO 82 (S82) DNA binding dye in a single reaction. We investigated the influence of the S82 on various TaqMan and melting analysis parameters and defined its optimal concentration. In the next step, the method was evaluated in 36 different TaqMan assays with a total of 729 paired reactions using various DNA and RNA templates, including field specimens. In addition, the melting profiles of interest were correlated with the electrophoretic patterns. We proved that the S82 is fully compatible with the FAM-TaqMan system. Further, the advantages of this approach in routine diagnostic TaqMan qPCR were illustrated with practical examples. These included solving problems with flat or other atypical amplification curves or even false negativity as a result of probe binding failure. Our data clearly show that the integration of the TaqMan qPCR and melting analysis into a single assay provides an additional control option as well as the opportunity to perform more complex analyses, get more data from the reactions, and obtain analysis results with higher confidence.  相似文献   
28.

Background

Neointima forming after stent implantation consists of vascular smooth muscle cells (VSMCs) in 90%. Growth factors TGF-β1, PDGFB, EGF, bFGF and VEGF-A play an important role in VSMC proliferation and migration to the tunica intima after arterial wall injury. The aim of this paper was an analysis of functional polymorphisms in genes encoding TGF-β1, PDGFB, EGF, bFGF and VEGF-A in relation to in-stent restenosis (ISR).

Materials and Methods

265 patients with a stable coronary artery disease (SCAD) hospitalized in our center in the years 2007–2011 were included in the study. All patients underwent stent implantation at admission to the hospital and had another coronary angiography performed due to recurrence of the ailments or a positive result of the test assessing the coronary flow reserve. Angiographically significant ISR was defined as stenosis >50% in the stented coronary artery segment. The patients were divided into two groups–with angiographically significant ISR (n = 53) and without significant ISR (n = 212). Additionally, the assessment of late lumen loss (LLL) in vessel was performed. EGF rs4444903 polymorphism was genotyped using the PCR-RFLP method whilst rs1800470 (TGFB1), rs2285094 (PDGFB) rs308395 (bFGF) and rs699947 (VEGF-A) were determined using the TaqMan method.

Results

Angiographically significant ISR was significantly less frequently observed in the group of patients with the A/A genotype of rs1800470 polymorphism (TGFB1) versus patients with A/G and G/G genotypes. In the multivariable analysis, LLL was significantly lower in patients with the A/A genotype of rs1800470 (TGFB1) versus those with the A/G and G/G genotypes and higher in patients with the A/A genotype of the VEGF-A polymorphism versus the A/C and C/C genotypes. The C/C genotype of rs2285094 (PDGFB) was associated with greater LLL compared to C/T heterozygotes and T/T homozygotes.

Conclusions

The polymorphisms rs1800470, rs2285094 and rs6999447 of the TGFB1, PDGFB and VEGF-A genes, respectively, are associated with LLL in patients with SCAD treated by PCI with a metal stent implantation.  相似文献   
29.
Reproductive functions are closely related to nutritional status. Recent studies suggest that adiponectin may be a hormonal link between them. Adiponectin is an adipocytokine, abundantly expressed in adipose tissues. It plays a dominant role in lipid and carbohydrate metabolism by stimulating fatty acid oxidation, decreasing plasma triglycerides, and increasing cells’ sensitivity to insulin and has direct antiatherosclerotic effects. The hormone is also postulated to play a modulatory role in the regulation of the reproductive system. The aim of this study was to identify differentially expressed genes (DE-genes) in response to adiponectin treatment of porcine luteal ovarian cells. The global expression of genes in the porcine ovary was investigated using the Porcine (V2) Two-color gene expression microarray, 4?×?44 (Agilent, USA). Analysis of the microarray data showed that 701 genes were differentially expressed and 389 genes showed a fold change greater than 1.2 (p?<?0.05). Among this number, 186 genes were up-regulated and 203 were down-regulated. The list of DE-genes was used for gene ontology analyses. The biological process list was generated from up-regulated and down-regulated DE-genes. We found that up-regulated products of DE-genes take part in 30 biological processes and down-regulated products in 9. Analysis of the interaction network among DE-genes showed that adiponectin interacts with genes involved in important processes in luteal cells. These results provide a basis for future work describing the detailed interactions and relationships explaining local regulation of adiponectin actions in the ovary of pigs.  相似文献   
30.
Bacteria that engage in long‐standing associations with particular hosts are expected to evolve host‐specific adaptations that limit their capacity to thrive in other environments. Consistent with this, many gut symbionts seem to have a limited host range, based on community profiling and phylogenomics. However, few studies have experimentally investigated host specialization of gut symbionts and the underlying mechanisms have largely remained elusive. Here, we studied host specialization of a dominant gut symbiont of social bees, Lactobacillus Firm5. We show that Firm5 strains isolated from honey bees and bumble bees separate into deep‐branching host‐specific phylogenetic lineages. Despite their divergent evolution, colonization experiments show that bumble bee strains are capable of colonizing the honey bee gut. However, they were less successful than honey bee strains, and competition with honey bee strains completely abolished their colonization. In contrast, honey bee strains of divergent phylogenetic lineages were able to coexist within individual bees. This suggests that both host selection and interbacterial competition play important roles in host specialization. Using comparative genomics of 27 Firm5 isolates, we found that the genomes of honey bee strains harbour more carbohydrate‐related functions than bumble bee strains, possibly providing a competitive advantage in the honey bee gut. Remarkably, most of the genes encoding carbohydrate‐related functions were not conserved among the honey bee strains, which suggests that honey bees can support a metabolically more diverse community of Firm5 strains than bumble bees. These findings advance our understanding of the genomic changes underlying host specialization.  相似文献   
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