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991.
Abstract A qualitative and semiquantitative assay was applied to estimate production of peripheral exopolymers by strains of bacteria isolated from flotation wastes during growth on copper sulphides and copper minerals wastes at neutral pH. Exopolymer production, expressed as percentage of Alcian Blue adsorption per μ g of cell protein, was the lowest on a complete organic medium and the highest on a nutrient-limited mineral medium. The exopolymer was highly resistant to acid hydrolysis and contained hydrocarbons, saturated and unsaturated fatty acids, aromatic acids and aromatic acid esters, which are well known as artificial surfactants and plasticizers. Carbohydrates appeared incidentally and in trace amount only. Chemical components of the exopolymer or chemically similar compounds also were found in black shale particles in the flotation wastes. 相似文献
992.
Aleksandra Taraszkiewicz Mariusz Grinholc Krzysztof P. Bielawski Anna Kawiak Joanna Nakonieczna 《Applied and environmental microbiology》2013,79(12):3692-3702
The objective of this study was to investigate a new potential photosensitizer (PS) in the photodynamic inactivation (PDI) of microorganisms in vitro (11 reference strains and 13 clinical isolates, representing common Gram-positive and Gram-negative human pathogens), with special emphasis on Candida albicans. We studied the light-induced cytotoxicity of the imidazoacridinone derivative C1330 toward fungal cells grown in planktonic form. We examined the influence of various parameters (time of incubation, PDI quencher effect, and C1330 accumulation in C. albicans cells) on the efficacy of light-dependent cytotoxicity. Additionally, we checked for the potential cyto- and phototoxic activity of C1330 against human dermal keratinocytes. In our research, we used a broadband incoherent blue light source (380 to 470 nm) with an output power of 100 mW/cm2. In vitro studies showed that the C1330 action against C. albicans was a light-dependent process. C1330 was an efficient photosensitizer in the photodynamic inactivation of C. albicans, which reduced the growth of planktonic cells by 6.1 log10 units. Efficient accumulation of PS in the nucleus and vacuoles was observed after 30 min of incubation, which correlated with the highest photokilling efficacy. Significant changes in intracellular structure were observed upon illumination of C1330-incubated C. albicans cells. In the case of the human HaCaT cell line, approximately 40% of cells survived the treatment, which indicates the potential benefit of further study of the application of C1330 in photoantimicrobial chemotherapy. These data suggest that PDI may be a viable approach for the treatment of localized C. albicans infections. 相似文献
993.
Bojana Vidović Brižita Đorđević Srđan Milovanović Sandra Škrivanj Zoran Pavlović Aleksandra Stefanović Jelena Kotur-Stevuljević 《Biological trace element research》2013,156(1-3):22-28
The aim of this study was to determine the plasma selenium (Se), copper (Cu), and zinc (Zn) levels and to evaluate their possible association with metabolic syndrome (MetS) components in patients with schizophrenia. The study group consisted of 60 patients with schizophrenia and 60 sex- and age-matched healthy controls. Anthropometric measurements, blood pressure, and biochemical analysis of fasting blood were performed in all subjects. Patients with schizophrenia had significantly higher plasma Cu concentrations compared with controls (0.97?±?0.31 vs. 0.77?±?0.32 mg/L, p?=?0.001). The plasma Cu concentration showed a positive correlation with plasma glucose and diastolic blood pressure in the patient groups (r s ?=?0.263, p?<?0.05 and r s ?=?0.272, p?<?0.05, respectively). The plasma Se level correlated positive with MetS score (r s ?=?0.385, p?<?0.01), waist circumference (r s ?=?0.344, p?<?0.05), plasma glucose (r s ?=?0.319, p?<?0.05), and triglyceride concentrations (r s ?=?0.462, p?<?0.001) in patients with schizophrenia. Plasma Zn did not correlate with any of the MetS components. These results suggest that alterations in plasma Cu and Se levels in medicated patients with schizophrenia could be associated with metabolic risk factors. 相似文献
994.
Maciej Pawlikowski Aleksandra Benko Tomasz P. Wróbel 《Origins of life and evolution of the biosphere》2013,43(2):119-127
Recent researches suggest participation of minerals in the formation of life under primordial conditions. Among all of the minerals, quartz seems to be one of the most probable to take part in such processes. However, an external source of energy is needed, e.g. electric discharge. A device simulating the proposed conditions was designed and was used to simulate prebiotic conditions. Investigation of processes occurring during the stimulation of quartz with electric discharge was studied by means of Ultraviolet–visible (UV–VIS) spectroscopy, in order to monitor the generation kinetics of free radicals. Additionally, infrared spectroscopy was applied to identify chemical reaction products created in a solution of alanine or glycine, in the presence of quartz treated with electric discharge. Formation of increased amounts of free radicals, compared to experiments performed without quartz and/or amino acid, is reported, along with identification of possible degradation products of alanine. No synthetic reactions were observed. 相似文献
995.
Alan Man Ching Ng Charis May Ngor Chan Mu Yao Guo Yu Hang Leung Aleksandra B. Djurišić Xu Hu Wai Kin Chan Frederick Chi Chung Leung Shuk Yin Tong 《Applied microbiology and biotechnology》2013,97(12):5565-5573
We studied antibacterial and photocatalytic activity of anatase TiO2 and ZnO in phosphate buffer and saline solution. We found that the different anions in the suspension medium (chloride and phosphate) significantly affected the following suspension properties: the stability of nanoparticle suspension, the release of metal ions from the nanoparticles, and the production of the reactive oxygen species by the nanoparticles. As a result, antibacterial activity and photocatalytic dye degradation were also affected. However, the effect of the suspension medium was different for ZnO and TiO2. Obtained results are discussed. 相似文献
996.
Jasmine Bhathena Christopher Martoni Arun Kulamarva Catherine Tomaro-Duchesneau Meenakshi Malhotra Arghya Paul Aleksandra Malgorzata Urbanska Satya Prakash 《PloS one》2013,8(3)
The beneficial effect of a microencapsulated feruloyl esterase producing Lactobacillus fermentum ATCC 11976 formulation for use in non-alcoholic fatty liver disease (NAFLD) was investigated. For which Bio F1B Golden Syrian hamsters were fed a methionine deficient/choline devoid diet to induce non-alcoholic fatty liver disease. Results, for the first time, show significant clinical benefits in experimental animals. Examination of lipids show that concentrations of hepatic free cholesterol, esterified cholesterol, triglycerides and phospholipids were significantly lowered in treated animals. In addition, serum total cholesterol, triglycerides, uric acid and insulin resistance were found to decrease in treated animals. Liver histology evaluations showed reduced fat deposits. Western blot analysis shows significant differences in expression levels of key liver enzymes in treated animals. In conclusion, these findings suggest the excellent potential of using an oral probiotic formulation to ameliorate NAFLD. 相似文献
997.
998.
Alison Lacombe Robert W. Li Dorothy Klimis-Zacas Aleksandra S. Kristo Shravani Tadepalli Emily Krauss Ryan Young Vivian C. H. Wu 《PloS one》2013,8(6)
The gastrointestinal tract is populated by an array of microbial species that play an important role in metabolic and immune functions. The composition of microorganisms is influenced by the components of the host’s diet and can impact health. In the present study, dietary enrichment of lowbush wild blueberries (LWB) was examined to determine their effect on colon microbial composition and their potential in promoting gut health. The microbial composition and functional potential of the colon microbiota from Sprague Dawley rats fed control diets (AIN93) and LWB-enriched diets (AIN93+8% LWB powder substituting for dextrose) for 6 weeks were assessed using Illumina shotgun sequencing and bioinformatics tools. Our analysis revealed an alteration in the relative abundance of 3 phyla and 22 genera as representing approximately 14 and 8% of all phyla and genera identified, respectively. The LWB-enriched diet resulted in a significant reduction in the relative abundance of the genera Lactobacillus and Enterococcus. In addition, hierarchal analysis revealed a significant increase in the relative abundance of the phylum Actinobacteria, the order Actinomycetales, and several novel genera under the family Bifidobacteriaceae and Coriobacteriaceae, in the LWB group. Functional annotation of the shotgun sequences suggested that approximately 9% of the 4709 Kyoto Encyclopaedia of Gene and Genome (KEGG) hits identified were impacted by the LWB-diet. Open Reading Frames (ORFs) assigned to KEGG category xenobiotics biodegradation and metabolism were significantly greater in the LWB-enriched diet compared to the control and included the pathway for benzoate degradation [PATH:ko00362] and glycosaminoglycan degradation [PATH:ko00531]. Moreover, the number of ORFs assigned to the bacterial invasion of epithelial cells [PATH:ko05100] pathway was approximately 8 fold lower in the LWB group compared to controls. This study demonstrated that LWBs have the potential to promote gut health and can aid in the development of optimal diets. 相似文献
999.
Myriam Mirza Cornelia Volz Marcus Karlstetter Monica Langiu Aleksandra Somogyi Mika O. Ruonala Ernst R. Tamm Herbert J?gle Thomas Langmann 《PloS one》2013,8(10)
Neuronal ceroid lipofuscinosis (NCL) is a group of neurodegenerative lysosomal storage disorders characterized by vision loss, mental and motor deficits, and spontaneous seizures. Neuropathological analyses of autopsy material from NCL patients and animal models revealed brain atrophy closely associated with glial activity. Earlier reports also noticed loss of retinal cells and reactive gliosis in some forms of NCL. To study this phenomenon in detail, we analyzed the ocular phenotype of CLN6nclf mice, an established mouse model for variant-late infantile NCL. Retinal morphometry, immunohistochemistry, optokinetic tracking, electroretinography, and mRNA expression were used to characterize retinal morphology and function as well as the responses of Müller cells and microglia. Our histological data showed a severe and progressive degeneration in the CLN6nclf retina co-inciding with reactive Müller glia. Furthermore, a prominent phenotypic transformation of ramified microglia to phagocytic, bloated, and mislocalized microglial cells was identified in CLN6nclf retinas. These events overlapped with a rapid loss of visual perception and retinal function. Based on the strong microglia reactivity we hypothesized that dietary supplementation with immuno-regulatory compounds, curcumin and docosahexaenoic acid (DHA), could ameliorate microgliosis and reduce retinal degeneration. Our analyses showed that treatment of three-week-old CLN6nclf mice with either 5% DHA or 0.6% curcumin for 30 weeks resulted in a reduced number of amoeboid reactive microglia and partially improved retinal function. DHA-treatment also improved the morphology of CLN6nclf retinas with a preserved thickness of the photoreceptor layer in most regions of the retina. Our results suggest that microglial reactivity closely accompanies disease progression in the CLN6nclf retina and both processes can be attenuated with dietary supplemented immuno-modulating compounds. 相似文献
1000.
Ryan T. Demmer Ludovic Trinquart Aleksandra Zuk Benjamin C. Fu Josefin Blomkvist Bryan S. Michalowicz Philippe Ravaud Mo?se Desvarieux 《PloS one》2013,8(10)